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Commit | Line | Data |
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8e86e015 | 1 | // SPDX-License-Identifier: GPL-2.0 |
0793a61d | 2 | /* |
57c0c15b | 3 | * Performance events core code: |
0793a61d | 4 | * |
98144511 | 5 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 7 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 8 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
0793a61d TG |
9 | */ |
10 | ||
11 | #include <linux/fs.h> | |
b9cacc7b | 12 | #include <linux/mm.h> |
0793a61d TG |
13 | #include <linux/cpu.h> |
14 | #include <linux/smp.h> | |
2e80a82a | 15 | #include <linux/idr.h> |
04289bb9 | 16 | #include <linux/file.h> |
0793a61d | 17 | #include <linux/poll.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
76e1d904 | 19 | #include <linux/hash.h> |
12351ef8 | 20 | #include <linux/tick.h> |
0793a61d | 21 | #include <linux/sysfs.h> |
22a4f650 | 22 | #include <linux/dcache.h> |
0793a61d | 23 | #include <linux/percpu.h> |
22a4f650 | 24 | #include <linux/ptrace.h> |
c277443c | 25 | #include <linux/reboot.h> |
b9cacc7b | 26 | #include <linux/vmstat.h> |
abe43400 | 27 | #include <linux/device.h> |
6e5fdeed | 28 | #include <linux/export.h> |
906010b2 | 29 | #include <linux/vmalloc.h> |
b9cacc7b | 30 | #include <linux/hardirq.h> |
03911132 | 31 | #include <linux/hugetlb.h> |
b9cacc7b | 32 | #include <linux/rculist.h> |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
375637bc AS |
47 | #include <linux/namei.h> |
48 | #include <linux/parser.h> | |
e6017571 | 49 | #include <linux/sched/clock.h> |
6e84f315 | 50 | #include <linux/sched/mm.h> |
e4222673 HB |
51 | #include <linux/proc_ns.h> |
52 | #include <linux/mount.h> | |
6eef8a71 | 53 | #include <linux/min_heap.h> |
8d97e718 | 54 | #include <linux/highmem.h> |
8af26be0 | 55 | #include <linux/pgtable.h> |
88a16a13 | 56 | #include <linux/buildid.h> |
0793a61d | 57 | |
76369139 FW |
58 | #include "internal.h" |
59 | ||
4e193bd4 TB |
60 | #include <asm/irq_regs.h> |
61 | ||
272325c4 PZ |
62 | typedef int (*remote_function_f)(void *); |
63 | ||
fe4b04fa | 64 | struct remote_function_call { |
e7e7ee2e | 65 | struct task_struct *p; |
272325c4 | 66 | remote_function_f func; |
e7e7ee2e IM |
67 | void *info; |
68 | int ret; | |
fe4b04fa PZ |
69 | }; |
70 | ||
71 | static void remote_function(void *data) | |
72 | { | |
73 | struct remote_function_call *tfc = data; | |
74 | struct task_struct *p = tfc->p; | |
75 | ||
76 | if (p) { | |
0da4cf3e PZ |
77 | /* -EAGAIN */ |
78 | if (task_cpu(p) != smp_processor_id()) | |
79 | return; | |
80 | ||
81 | /* | |
82 | * Now that we're on right CPU with IRQs disabled, we can test | |
83 | * if we hit the right task without races. | |
84 | */ | |
85 | ||
86 | tfc->ret = -ESRCH; /* No such (running) process */ | |
87 | if (p != current) | |
fe4b04fa PZ |
88 | return; |
89 | } | |
90 | ||
91 | tfc->ret = tfc->func(tfc->info); | |
92 | } | |
93 | ||
94 | /** | |
95 | * task_function_call - call a function on the cpu on which a task runs | |
96 | * @p: the task to evaluate | |
97 | * @func: the function to be called | |
98 | * @info: the function call argument | |
99 | * | |
100 | * Calls the function @func when the task is currently running. This might | |
2ed6edd3 BR |
101 | * be on the current CPU, which just calls the function directly. This will |
102 | * retry due to any failures in smp_call_function_single(), such as if the | |
103 | * task_cpu() goes offline concurrently. | |
fe4b04fa | 104 | * |
6d6b8b9f | 105 | * returns @func return value or -ESRCH or -ENXIO when the process isn't running |
fe4b04fa PZ |
106 | */ |
107 | static int | |
272325c4 | 108 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
109 | { |
110 | struct remote_function_call data = { | |
e7e7ee2e IM |
111 | .p = p, |
112 | .func = func, | |
113 | .info = info, | |
0da4cf3e | 114 | .ret = -EAGAIN, |
fe4b04fa | 115 | }; |
0da4cf3e | 116 | int ret; |
fe4b04fa | 117 | |
2ed6edd3 BR |
118 | for (;;) { |
119 | ret = smp_call_function_single(task_cpu(p), remote_function, | |
120 | &data, 1); | |
6d6b8b9f KJ |
121 | if (!ret) |
122 | ret = data.ret; | |
2ed6edd3 BR |
123 | |
124 | if (ret != -EAGAIN) | |
125 | break; | |
126 | ||
127 | cond_resched(); | |
128 | } | |
fe4b04fa | 129 | |
0da4cf3e | 130 | return ret; |
fe4b04fa PZ |
131 | } |
132 | ||
133 | /** | |
134 | * cpu_function_call - call a function on the cpu | |
a1ddf524 | 135 | * @cpu: target cpu to queue this function |
fe4b04fa PZ |
136 | * @func: the function to be called |
137 | * @info: the function call argument | |
138 | * | |
139 | * Calls the function @func on the remote cpu. | |
140 | * | |
141 | * returns: @func return value or -ENXIO when the cpu is offline | |
142 | */ | |
272325c4 | 143 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
144 | { |
145 | struct remote_function_call data = { | |
e7e7ee2e IM |
146 | .p = NULL, |
147 | .func = func, | |
148 | .info = info, | |
149 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
150 | }; |
151 | ||
152 | smp_call_function_single(cpu, remote_function, &data, 1); | |
153 | ||
154 | return data.ret; | |
155 | } | |
156 | ||
fae3fde6 PZ |
157 | static inline struct perf_cpu_context * |
158 | __get_cpu_context(struct perf_event_context *ctx) | |
159 | { | |
160 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
161 | } | |
162 | ||
163 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
164 | struct perf_event_context *ctx) | |
0017960f | 165 | { |
fae3fde6 PZ |
166 | raw_spin_lock(&cpuctx->ctx.lock); |
167 | if (ctx) | |
168 | raw_spin_lock(&ctx->lock); | |
169 | } | |
170 | ||
171 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
172 | struct perf_event_context *ctx) | |
173 | { | |
174 | if (ctx) | |
175 | raw_spin_unlock(&ctx->lock); | |
176 | raw_spin_unlock(&cpuctx->ctx.lock); | |
177 | } | |
178 | ||
63b6da39 PZ |
179 | #define TASK_TOMBSTONE ((void *)-1L) |
180 | ||
181 | static bool is_kernel_event(struct perf_event *event) | |
182 | { | |
f47c02c0 | 183 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
184 | } |
185 | ||
39a43640 PZ |
186 | /* |
187 | * On task ctx scheduling... | |
188 | * | |
189 | * When !ctx->nr_events a task context will not be scheduled. This means | |
190 | * we can disable the scheduler hooks (for performance) without leaving | |
191 | * pending task ctx state. | |
192 | * | |
193 | * This however results in two special cases: | |
194 | * | |
195 | * - removing the last event from a task ctx; this is relatively straight | |
196 | * forward and is done in __perf_remove_from_context. | |
197 | * | |
198 | * - adding the first event to a task ctx; this is tricky because we cannot | |
199 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
200 | * See perf_install_in_context(). | |
201 | * | |
39a43640 PZ |
202 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
203 | */ | |
204 | ||
fae3fde6 PZ |
205 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
206 | struct perf_event_context *, void *); | |
207 | ||
208 | struct event_function_struct { | |
209 | struct perf_event *event; | |
210 | event_f func; | |
211 | void *data; | |
212 | }; | |
213 | ||
214 | static int event_function(void *info) | |
215 | { | |
216 | struct event_function_struct *efs = info; | |
217 | struct perf_event *event = efs->event; | |
0017960f | 218 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
219 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
220 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 221 | int ret = 0; |
fae3fde6 | 222 | |
16444645 | 223 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 224 | |
63b6da39 | 225 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
226 | /* |
227 | * Since we do the IPI call without holding ctx->lock things can have | |
228 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
229 | */ |
230 | if (ctx->task) { | |
63b6da39 | 231 | if (ctx->task != current) { |
0da4cf3e | 232 | ret = -ESRCH; |
63b6da39 PZ |
233 | goto unlock; |
234 | } | |
fae3fde6 | 235 | |
fae3fde6 PZ |
236 | /* |
237 | * We only use event_function_call() on established contexts, | |
238 | * and event_function() is only ever called when active (or | |
239 | * rather, we'll have bailed in task_function_call() or the | |
240 | * above ctx->task != current test), therefore we must have | |
241 | * ctx->is_active here. | |
242 | */ | |
243 | WARN_ON_ONCE(!ctx->is_active); | |
244 | /* | |
245 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
246 | * match. | |
247 | */ | |
63b6da39 PZ |
248 | WARN_ON_ONCE(task_ctx != ctx); |
249 | } else { | |
250 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 251 | } |
63b6da39 | 252 | |
fae3fde6 | 253 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 254 | unlock: |
fae3fde6 PZ |
255 | perf_ctx_unlock(cpuctx, task_ctx); |
256 | ||
63b6da39 | 257 | return ret; |
fae3fde6 PZ |
258 | } |
259 | ||
fae3fde6 | 260 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
261 | { |
262 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 263 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
264 | struct event_function_struct efs = { |
265 | .event = event, | |
266 | .func = func, | |
267 | .data = data, | |
268 | }; | |
0017960f | 269 | |
c97f4736 PZ |
270 | if (!event->parent) { |
271 | /* | |
272 | * If this is a !child event, we must hold ctx::mutex to | |
c034f48e | 273 | * stabilize the event->ctx relation. See |
c97f4736 PZ |
274 | * perf_event_ctx_lock(). |
275 | */ | |
276 | lockdep_assert_held(&ctx->mutex); | |
277 | } | |
0017960f PZ |
278 | |
279 | if (!task) { | |
fae3fde6 | 280 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
281 | return; |
282 | } | |
283 | ||
63b6da39 PZ |
284 | if (task == TASK_TOMBSTONE) |
285 | return; | |
286 | ||
a096309b | 287 | again: |
fae3fde6 | 288 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
289 | return; |
290 | ||
291 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
292 | /* |
293 | * Reload the task pointer, it might have been changed by | |
294 | * a concurrent perf_event_context_sched_out(). | |
295 | */ | |
296 | task = ctx->task; | |
a096309b PZ |
297 | if (task == TASK_TOMBSTONE) { |
298 | raw_spin_unlock_irq(&ctx->lock); | |
299 | return; | |
0017960f | 300 | } |
a096309b PZ |
301 | if (ctx->is_active) { |
302 | raw_spin_unlock_irq(&ctx->lock); | |
303 | goto again; | |
304 | } | |
305 | func(event, NULL, ctx, data); | |
0017960f PZ |
306 | raw_spin_unlock_irq(&ctx->lock); |
307 | } | |
308 | ||
cca20946 PZ |
309 | /* |
310 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
311 | * are already disabled and we're on the right CPU. | |
312 | */ | |
313 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
314 | { | |
315 | struct perf_event_context *ctx = event->ctx; | |
316 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
317 | struct task_struct *task = READ_ONCE(ctx->task); | |
318 | struct perf_event_context *task_ctx = NULL; | |
319 | ||
16444645 | 320 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
321 | |
322 | if (task) { | |
323 | if (task == TASK_TOMBSTONE) | |
324 | return; | |
325 | ||
326 | task_ctx = ctx; | |
327 | } | |
328 | ||
329 | perf_ctx_lock(cpuctx, task_ctx); | |
330 | ||
331 | task = ctx->task; | |
332 | if (task == TASK_TOMBSTONE) | |
333 | goto unlock; | |
334 | ||
335 | if (task) { | |
336 | /* | |
337 | * We must be either inactive or active and the right task, | |
338 | * otherwise we're screwed, since we cannot IPI to somewhere | |
339 | * else. | |
340 | */ | |
341 | if (ctx->is_active) { | |
342 | if (WARN_ON_ONCE(task != current)) | |
343 | goto unlock; | |
344 | ||
345 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
346 | goto unlock; | |
347 | } | |
348 | } else { | |
349 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
350 | } | |
351 | ||
352 | func(event, cpuctx, ctx, data); | |
353 | unlock: | |
354 | perf_ctx_unlock(cpuctx, task_ctx); | |
355 | } | |
356 | ||
e5d1367f SE |
357 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
358 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
359 | PERF_FLAG_PID_CGROUP |\ |
360 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 361 | |
bce38cd5 SE |
362 | /* |
363 | * branch priv levels that need permission checks | |
364 | */ | |
365 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
366 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
367 | PERF_SAMPLE_BRANCH_HV) | |
368 | ||
0b3fcf17 SE |
369 | enum event_type_t { |
370 | EVENT_FLEXIBLE = 0x1, | |
371 | EVENT_PINNED = 0x2, | |
3cbaa590 | 372 | EVENT_TIME = 0x4, |
487f05e1 AS |
373 | /* see ctx_resched() for details */ |
374 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
375 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
376 | }; | |
377 | ||
e5d1367f SE |
378 | /* |
379 | * perf_sched_events : >0 events exist | |
380 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
381 | */ | |
9107c89e PZ |
382 | |
383 | static void perf_sched_delayed(struct work_struct *work); | |
384 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
385 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
386 | static DEFINE_MUTEX(perf_sched_mutex); | |
387 | static atomic_t perf_sched_count; | |
388 | ||
e5d1367f | 389 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
a5398bff | 390 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 391 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 392 | |
cdd6c482 IM |
393 | static atomic_t nr_mmap_events __read_mostly; |
394 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 395 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 396 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 397 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 398 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 399 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 400 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 401 | static atomic_t nr_cgroup_events __read_mostly; |
e17d43b9 | 402 | static atomic_t nr_text_poke_events __read_mostly; |
88a16a13 | 403 | static atomic_t nr_build_id_events __read_mostly; |
9ee318a7 | 404 | |
108b02cf PZ |
405 | static LIST_HEAD(pmus); |
406 | static DEFINE_MUTEX(pmus_lock); | |
407 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 408 | static cpumask_var_t perf_online_mask; |
bdacfaf2 | 409 | static struct kmem_cache *perf_event_cache; |
108b02cf | 410 | |
0764771d | 411 | /* |
cdd6c482 | 412 | * perf event paranoia level: |
0fbdea19 IM |
413 | * -1 - not paranoid at all |
414 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 415 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 416 | * 2 - disallow kernel profiling for unpriv |
0764771d | 417 | */ |
0161028b | 418 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 419 | |
20443384 FW |
420 | /* Minimum for 512 kiB + 1 user control page */ |
421 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
422 | |
423 | /* | |
cdd6c482 | 424 | * max perf event sample rate |
df58ab24 | 425 | */ |
14c63f17 DH |
426 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
427 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
428 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
429 | ||
430 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
431 | ||
432 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
433 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
434 | ||
d9494cb4 PZ |
435 | static int perf_sample_allowed_ns __read_mostly = |
436 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 437 | |
18ab2cd3 | 438 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
439 | { |
440 | u64 tmp = perf_sample_period_ns; | |
441 | ||
442 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
443 | tmp = div_u64(tmp, 100); |
444 | if (!tmp) | |
445 | tmp = 1; | |
446 | ||
447 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 448 | } |
163ec435 | 449 | |
8d5bce0c | 450 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 451 | |
163ec435 | 452 | int perf_proc_update_handler(struct ctl_table *table, int write, |
32927393 | 453 | void *buffer, size_t *lenp, loff_t *ppos) |
163ec435 | 454 | { |
1a51c5da SE |
455 | int ret; |
456 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
457 | /* |
458 | * If throttling is disabled don't allow the write: | |
459 | */ | |
1a51c5da | 460 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
461 | return -EINVAL; |
462 | ||
1a51c5da SE |
463 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
464 | if (ret || !write) | |
465 | return ret; | |
466 | ||
163ec435 | 467 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
468 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
469 | update_perf_cpu_limits(); | |
470 | ||
471 | return 0; | |
472 | } | |
473 | ||
474 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
475 | ||
476 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
32927393 | 477 | void *buffer, size_t *lenp, loff_t *ppos) |
14c63f17 | 478 | { |
1572e45a | 479 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
480 | |
481 | if (ret || !write) | |
482 | return ret; | |
483 | ||
b303e7c1 PZ |
484 | if (sysctl_perf_cpu_time_max_percent == 100 || |
485 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
486 | printk(KERN_WARNING |
487 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
488 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
489 | } else { | |
490 | update_perf_cpu_limits(); | |
491 | } | |
163ec435 PZ |
492 | |
493 | return 0; | |
494 | } | |
1ccd1549 | 495 | |
14c63f17 DH |
496 | /* |
497 | * perf samples are done in some very critical code paths (NMIs). | |
498 | * If they take too much CPU time, the system can lock up and not | |
499 | * get any real work done. This will drop the sample rate when | |
500 | * we detect that events are taking too long. | |
501 | */ | |
502 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 503 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 504 | |
91a612ee PZ |
505 | static u64 __report_avg; |
506 | static u64 __report_allowed; | |
507 | ||
6a02ad66 | 508 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 509 | { |
0d87d7ec | 510 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
511 | "perf: interrupt took too long (%lld > %lld), lowering " |
512 | "kernel.perf_event_max_sample_rate to %d\n", | |
513 | __report_avg, __report_allowed, | |
514 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
515 | } |
516 | ||
517 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
518 | ||
519 | void perf_sample_event_took(u64 sample_len_ns) | |
520 | { | |
91a612ee PZ |
521 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
522 | u64 running_len; | |
523 | u64 avg_len; | |
524 | u32 max; | |
14c63f17 | 525 | |
91a612ee | 526 | if (max_len == 0) |
14c63f17 DH |
527 | return; |
528 | ||
91a612ee PZ |
529 | /* Decay the counter by 1 average sample. */ |
530 | running_len = __this_cpu_read(running_sample_length); | |
531 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
532 | running_len += sample_len_ns; | |
533 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
534 | |
535 | /* | |
91a612ee PZ |
536 | * Note: this will be biased artifically low until we have |
537 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
538 | * from having to maintain a count. |
539 | */ | |
91a612ee PZ |
540 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
541 | if (avg_len <= max_len) | |
14c63f17 DH |
542 | return; |
543 | ||
91a612ee PZ |
544 | __report_avg = avg_len; |
545 | __report_allowed = max_len; | |
14c63f17 | 546 | |
91a612ee PZ |
547 | /* |
548 | * Compute a throttle threshold 25% below the current duration. | |
549 | */ | |
550 | avg_len += avg_len / 4; | |
551 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
552 | if (avg_len < max) | |
553 | max /= (u32)avg_len; | |
554 | else | |
555 | max = 1; | |
14c63f17 | 556 | |
91a612ee PZ |
557 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
558 | WRITE_ONCE(max_samples_per_tick, max); | |
559 | ||
560 | sysctl_perf_event_sample_rate = max * HZ; | |
561 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 562 | |
cd578abb | 563 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 564 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 565 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 566 | __report_avg, __report_allowed, |
cd578abb PZ |
567 | sysctl_perf_event_sample_rate); |
568 | } | |
14c63f17 DH |
569 | } |
570 | ||
cdd6c482 | 571 | static atomic64_t perf_event_id; |
a96bbc16 | 572 | |
0b3fcf17 SE |
573 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
574 | enum event_type_t event_type); | |
575 | ||
576 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
577 | enum event_type_t event_type, |
578 | struct task_struct *task); | |
579 | ||
580 | static void update_context_time(struct perf_event_context *ctx); | |
581 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 582 | |
cdd6c482 | 583 | void __weak perf_event_print_debug(void) { } |
0793a61d | 584 | |
0b3fcf17 SE |
585 | static inline u64 perf_clock(void) |
586 | { | |
587 | return local_clock(); | |
588 | } | |
589 | ||
34f43927 PZ |
590 | static inline u64 perf_event_clock(struct perf_event *event) |
591 | { | |
592 | return event->clock(); | |
593 | } | |
594 | ||
0d3d73aa PZ |
595 | /* |
596 | * State based event timekeeping... | |
597 | * | |
598 | * The basic idea is to use event->state to determine which (if any) time | |
599 | * fields to increment with the current delta. This means we only need to | |
600 | * update timestamps when we change state or when they are explicitly requested | |
601 | * (read). | |
602 | * | |
603 | * Event groups make things a little more complicated, but not terribly so. The | |
604 | * rules for a group are that if the group leader is OFF the entire group is | |
605 | * OFF, irrespecive of what the group member states are. This results in | |
606 | * __perf_effective_state(). | |
607 | * | |
608 | * A futher ramification is that when a group leader flips between OFF and | |
609 | * !OFF, we need to update all group member times. | |
610 | * | |
611 | * | |
612 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
613 | * need to make sure the relevant context time is updated before we try and | |
614 | * update our timestamps. | |
615 | */ | |
616 | ||
617 | static __always_inline enum perf_event_state | |
618 | __perf_effective_state(struct perf_event *event) | |
619 | { | |
620 | struct perf_event *leader = event->group_leader; | |
621 | ||
622 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
623 | return leader->state; | |
624 | ||
625 | return event->state; | |
626 | } | |
627 | ||
628 | static __always_inline void | |
629 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
630 | { | |
631 | enum perf_event_state state = __perf_effective_state(event); | |
632 | u64 delta = now - event->tstamp; | |
633 | ||
634 | *enabled = event->total_time_enabled; | |
635 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
636 | *enabled += delta; | |
637 | ||
638 | *running = event->total_time_running; | |
639 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
640 | *running += delta; | |
641 | } | |
642 | ||
643 | static void perf_event_update_time(struct perf_event *event) | |
644 | { | |
645 | u64 now = perf_event_time(event); | |
646 | ||
647 | __perf_update_times(event, now, &event->total_time_enabled, | |
648 | &event->total_time_running); | |
649 | event->tstamp = now; | |
650 | } | |
651 | ||
652 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
653 | { | |
654 | struct perf_event *sibling; | |
655 | ||
edb39592 | 656 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
657 | perf_event_update_time(sibling); |
658 | } | |
659 | ||
660 | static void | |
661 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
662 | { | |
663 | if (event->state == state) | |
664 | return; | |
665 | ||
666 | perf_event_update_time(event); | |
667 | /* | |
668 | * If a group leader gets enabled/disabled all its siblings | |
669 | * are affected too. | |
670 | */ | |
671 | if ((event->state < 0) ^ (state < 0)) | |
672 | perf_event_update_sibling_time(event); | |
673 | ||
674 | WRITE_ONCE(event->state, state); | |
675 | } | |
676 | ||
e5d1367f SE |
677 | #ifdef CONFIG_CGROUP_PERF |
678 | ||
e5d1367f SE |
679 | static inline bool |
680 | perf_cgroup_match(struct perf_event *event) | |
681 | { | |
682 | struct perf_event_context *ctx = event->ctx; | |
683 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
684 | ||
ef824fa1 TH |
685 | /* @event doesn't care about cgroup */ |
686 | if (!event->cgrp) | |
687 | return true; | |
688 | ||
689 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
690 | if (!cpuctx->cgrp) | |
691 | return false; | |
692 | ||
693 | /* | |
694 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
695 | * also enabled for all its descendant cgroups. If @cpuctx's | |
696 | * cgroup is a descendant of @event's (the test covers identity | |
697 | * case), it's a match. | |
698 | */ | |
699 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
700 | event->cgrp->css.cgroup); | |
e5d1367f SE |
701 | } |
702 | ||
e5d1367f SE |
703 | static inline void perf_detach_cgroup(struct perf_event *event) |
704 | { | |
4e2ba650 | 705 | css_put(&event->cgrp->css); |
e5d1367f SE |
706 | event->cgrp = NULL; |
707 | } | |
708 | ||
709 | static inline int is_cgroup_event(struct perf_event *event) | |
710 | { | |
711 | return event->cgrp != NULL; | |
712 | } | |
713 | ||
714 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
715 | { | |
716 | struct perf_cgroup_info *t; | |
717 | ||
718 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
719 | return t->time; | |
720 | } | |
721 | ||
722 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
723 | { | |
724 | struct perf_cgroup_info *info; | |
725 | u64 now; | |
726 | ||
727 | now = perf_clock(); | |
728 | ||
729 | info = this_cpu_ptr(cgrp->info); | |
730 | ||
731 | info->time += now - info->timestamp; | |
732 | info->timestamp = now; | |
733 | } | |
734 | ||
735 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
736 | { | |
c917e0f2 SL |
737 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
738 | struct cgroup_subsys_state *css; | |
739 | ||
740 | if (cgrp) { | |
741 | for (css = &cgrp->css; css; css = css->parent) { | |
742 | cgrp = container_of(css, struct perf_cgroup, css); | |
743 | __update_cgrp_time(cgrp); | |
744 | } | |
745 | } | |
e5d1367f SE |
746 | } |
747 | ||
748 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
749 | { | |
3f7cce3c SE |
750 | struct perf_cgroup *cgrp; |
751 | ||
e5d1367f | 752 | /* |
3f7cce3c SE |
753 | * ensure we access cgroup data only when needed and |
754 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 755 | */ |
3f7cce3c | 756 | if (!is_cgroup_event(event)) |
e5d1367f SE |
757 | return; |
758 | ||
614e4c4e | 759 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
760 | /* |
761 | * Do not update time when cgroup is not active | |
762 | */ | |
28fa741c | 763 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 764 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
765 | } |
766 | ||
767 | static inline void | |
3f7cce3c SE |
768 | perf_cgroup_set_timestamp(struct task_struct *task, |
769 | struct perf_event_context *ctx) | |
e5d1367f SE |
770 | { |
771 | struct perf_cgroup *cgrp; | |
772 | struct perf_cgroup_info *info; | |
c917e0f2 | 773 | struct cgroup_subsys_state *css; |
e5d1367f | 774 | |
3f7cce3c SE |
775 | /* |
776 | * ctx->lock held by caller | |
777 | * ensure we do not access cgroup data | |
778 | * unless we have the cgroup pinned (css_get) | |
779 | */ | |
780 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
781 | return; |
782 | ||
614e4c4e | 783 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
784 | |
785 | for (css = &cgrp->css; css; css = css->parent) { | |
786 | cgrp = container_of(css, struct perf_cgroup, css); | |
787 | info = this_cpu_ptr(cgrp->info); | |
788 | info->timestamp = ctx->timestamp; | |
789 | } | |
e5d1367f SE |
790 | } |
791 | ||
058fe1c0 DCC |
792 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
793 | ||
e5d1367f SE |
794 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
795 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
796 | ||
797 | /* | |
798 | * reschedule events based on the cgroup constraint of task. | |
799 | * | |
800 | * mode SWOUT : schedule out everything | |
801 | * mode SWIN : schedule in based on cgroup for next | |
802 | */ | |
18ab2cd3 | 803 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
804 | { |
805 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 806 | struct list_head *list; |
e5d1367f SE |
807 | unsigned long flags; |
808 | ||
809 | /* | |
058fe1c0 DCC |
810 | * Disable interrupts and preemption to avoid this CPU's |
811 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
812 | */ |
813 | local_irq_save(flags); | |
814 | ||
058fe1c0 DCC |
815 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
816 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
817 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 818 | |
058fe1c0 DCC |
819 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
820 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 821 | |
058fe1c0 DCC |
822 | if (mode & PERF_CGROUP_SWOUT) { |
823 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
824 | /* | |
825 | * must not be done before ctxswout due | |
826 | * to event_filter_match() in event_sched_out() | |
827 | */ | |
828 | cpuctx->cgrp = NULL; | |
829 | } | |
e5d1367f | 830 | |
058fe1c0 DCC |
831 | if (mode & PERF_CGROUP_SWIN) { |
832 | WARN_ON_ONCE(cpuctx->cgrp); | |
833 | /* | |
834 | * set cgrp before ctxsw in to allow | |
835 | * event_filter_match() to not have to pass | |
836 | * task around | |
837 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
838 | * because cgorup events are only per-cpu | |
839 | */ | |
840 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
841 | &cpuctx->ctx); | |
842 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 843 | } |
058fe1c0 DCC |
844 | perf_pmu_enable(cpuctx->ctx.pmu); |
845 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
846 | } |
847 | ||
e5d1367f SE |
848 | local_irq_restore(flags); |
849 | } | |
850 | ||
a8d757ef SE |
851 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
852 | struct task_struct *next) | |
e5d1367f | 853 | { |
a8d757ef SE |
854 | struct perf_cgroup *cgrp1; |
855 | struct perf_cgroup *cgrp2 = NULL; | |
856 | ||
ddaaf4e2 | 857 | rcu_read_lock(); |
a8d757ef SE |
858 | /* |
859 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
860 | * we do not need to pass the ctx here because we know |
861 | * we are holding the rcu lock | |
a8d757ef | 862 | */ |
614e4c4e | 863 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 864 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
865 | |
866 | /* | |
867 | * only schedule out current cgroup events if we know | |
868 | * that we are switching to a different cgroup. Otherwise, | |
869 | * do no touch the cgroup events. | |
870 | */ | |
871 | if (cgrp1 != cgrp2) | |
872 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
873 | |
874 | rcu_read_unlock(); | |
e5d1367f SE |
875 | } |
876 | ||
a8d757ef SE |
877 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
878 | struct task_struct *task) | |
e5d1367f | 879 | { |
a8d757ef SE |
880 | struct perf_cgroup *cgrp1; |
881 | struct perf_cgroup *cgrp2 = NULL; | |
882 | ||
ddaaf4e2 | 883 | rcu_read_lock(); |
a8d757ef SE |
884 | /* |
885 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
886 | * we do not need to pass the ctx here because we know |
887 | * we are holding the rcu lock | |
a8d757ef | 888 | */ |
614e4c4e | 889 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 890 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
891 | |
892 | /* | |
893 | * only need to schedule in cgroup events if we are changing | |
894 | * cgroup during ctxsw. Cgroup events were not scheduled | |
895 | * out of ctxsw out if that was not the case. | |
896 | */ | |
897 | if (cgrp1 != cgrp2) | |
898 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
899 | |
900 | rcu_read_unlock(); | |
e5d1367f SE |
901 | } |
902 | ||
c2283c93 IR |
903 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
904 | struct cgroup_subsys_state *css) | |
905 | { | |
906 | struct perf_cpu_context *cpuctx; | |
907 | struct perf_event **storage; | |
908 | int cpu, heap_size, ret = 0; | |
909 | ||
910 | /* | |
911 | * Allow storage to have sufficent space for an iterator for each | |
912 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
913 | */ | |
914 | for (heap_size = 1; css; css = css->parent) | |
915 | heap_size++; | |
916 | ||
917 | for_each_possible_cpu(cpu) { | |
918 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
919 | if (heap_size <= cpuctx->heap_size) | |
920 | continue; | |
921 | ||
922 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
923 | GFP_KERNEL, cpu_to_node(cpu)); | |
924 | if (!storage) { | |
925 | ret = -ENOMEM; | |
926 | break; | |
927 | } | |
928 | ||
929 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
930 | if (cpuctx->heap_size < heap_size) { | |
931 | swap(cpuctx->heap, storage); | |
932 | if (storage == cpuctx->heap_default) | |
933 | storage = NULL; | |
934 | cpuctx->heap_size = heap_size; | |
935 | } | |
936 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
937 | ||
938 | kfree(storage); | |
939 | } | |
940 | ||
941 | return ret; | |
942 | } | |
943 | ||
e5d1367f SE |
944 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
945 | struct perf_event_attr *attr, | |
946 | struct perf_event *group_leader) | |
947 | { | |
948 | struct perf_cgroup *cgrp; | |
949 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
950 | struct fd f = fdget(fd); |
951 | int ret = 0; | |
e5d1367f | 952 | |
2903ff01 | 953 | if (!f.file) |
e5d1367f SE |
954 | return -EBADF; |
955 | ||
b583043e | 956 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 957 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
958 | if (IS_ERR(css)) { |
959 | ret = PTR_ERR(css); | |
960 | goto out; | |
961 | } | |
e5d1367f | 962 | |
c2283c93 IR |
963 | ret = perf_cgroup_ensure_storage(event, css); |
964 | if (ret) | |
965 | goto out; | |
966 | ||
e5d1367f SE |
967 | cgrp = container_of(css, struct perf_cgroup, css); |
968 | event->cgrp = cgrp; | |
969 | ||
970 | /* | |
971 | * all events in a group must monitor | |
972 | * the same cgroup because a task belongs | |
973 | * to only one perf cgroup at a time | |
974 | */ | |
975 | if (group_leader && group_leader->cgrp != cgrp) { | |
976 | perf_detach_cgroup(event); | |
977 | ret = -EINVAL; | |
e5d1367f | 978 | } |
3db272c0 | 979 | out: |
2903ff01 | 980 | fdput(f); |
e5d1367f SE |
981 | return ret; |
982 | } | |
983 | ||
984 | static inline void | |
985 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
986 | { | |
987 | struct perf_cgroup_info *t; | |
988 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
989 | event->shadow_ctx_time = now - t->timestamp; | |
990 | } | |
991 | ||
db4a8356 | 992 | static inline void |
33238c50 | 993 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
994 | { |
995 | struct perf_cpu_context *cpuctx; | |
996 | ||
997 | if (!is_cgroup_event(event)) | |
998 | return; | |
999 | ||
db4a8356 DCC |
1000 | /* |
1001 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1002 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1003 | */ |
07c59729 | 1004 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1005 | |
1006 | /* | |
1007 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1008 | * matching the event's cgroup, we must do this for every new event, | |
1009 | * because if the first would mismatch, the second would not try again | |
1010 | * and we would leave cpuctx->cgrp unset. | |
1011 | */ | |
33238c50 | 1012 | if (ctx->is_active && !cpuctx->cgrp) { |
be96b316 TH |
1013 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1014 | ||
be96b316 TH |
1015 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1016 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1017 | } |
33801b94 | 1018 | |
33238c50 | 1019 | if (ctx->nr_cgroups++) |
33801b94 | 1020 | return; |
33238c50 PZ |
1021 | |
1022 | list_add(&cpuctx->cgrp_cpuctx_entry, | |
1023 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
1024 | } | |
1025 | ||
1026 | static inline void | |
1027 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1028 | { | |
1029 | struct perf_cpu_context *cpuctx; | |
1030 | ||
1031 | if (!is_cgroup_event(event)) | |
33801b94 | 1032 | return; |
1033 | ||
33238c50 PZ |
1034 | /* |
1035 | * Because cgroup events are always per-cpu events, | |
1036 | * @ctx == &cpuctx->ctx. | |
1037 | */ | |
1038 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); | |
1039 | ||
1040 | if (--ctx->nr_cgroups) | |
1041 | return; | |
1042 | ||
1043 | if (ctx->is_active && cpuctx->cgrp) | |
33801b94 | 1044 | cpuctx->cgrp = NULL; |
1045 | ||
33238c50 | 1046 | list_del(&cpuctx->cgrp_cpuctx_entry); |
db4a8356 DCC |
1047 | } |
1048 | ||
e5d1367f SE |
1049 | #else /* !CONFIG_CGROUP_PERF */ |
1050 | ||
1051 | static inline bool | |
1052 | perf_cgroup_match(struct perf_event *event) | |
1053 | { | |
1054 | return true; | |
1055 | } | |
1056 | ||
1057 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1058 | {} | |
1059 | ||
1060 | static inline int is_cgroup_event(struct perf_event *event) | |
1061 | { | |
1062 | return 0; | |
1063 | } | |
1064 | ||
e5d1367f SE |
1065 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1066 | { | |
1067 | } | |
1068 | ||
1069 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1070 | { | |
1071 | } | |
1072 | ||
a8d757ef SE |
1073 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1074 | struct task_struct *next) | |
e5d1367f SE |
1075 | { |
1076 | } | |
1077 | ||
a8d757ef SE |
1078 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1079 | struct task_struct *task) | |
e5d1367f SE |
1080 | { |
1081 | } | |
1082 | ||
1083 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1084 | struct perf_event_attr *attr, | |
1085 | struct perf_event *group_leader) | |
1086 | { | |
1087 | return -EINVAL; | |
1088 | } | |
1089 | ||
1090 | static inline void | |
3f7cce3c SE |
1091 | perf_cgroup_set_timestamp(struct task_struct *task, |
1092 | struct perf_event_context *ctx) | |
e5d1367f SE |
1093 | { |
1094 | } | |
1095 | ||
d00dbd29 | 1096 | static inline void |
e5d1367f SE |
1097 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1098 | { | |
1099 | } | |
1100 | ||
1101 | static inline void | |
1102 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1103 | { | |
1104 | } | |
1105 | ||
1106 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1107 | { | |
1108 | return 0; | |
1109 | } | |
1110 | ||
db4a8356 | 1111 | static inline void |
33238c50 | 1112 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1113 | { |
1114 | } | |
1115 | ||
33238c50 PZ |
1116 | static inline void |
1117 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1118 | { | |
1119 | } | |
e5d1367f SE |
1120 | #endif |
1121 | ||
9e630205 SE |
1122 | /* |
1123 | * set default to be dependent on timer tick just | |
1124 | * like original code | |
1125 | */ | |
1126 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1127 | /* | |
8a1115ff | 1128 | * function must be called with interrupts disabled |
9e630205 | 1129 | */ |
272325c4 | 1130 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1131 | { |
1132 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1133 | bool rotations; |
9e630205 | 1134 | |
16444645 | 1135 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1136 | |
1137 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1138 | rotations = perf_rotate_context(cpuctx); |
1139 | ||
4cfafd30 PZ |
1140 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1141 | if (rotations) | |
9e630205 | 1142 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1143 | else |
1144 | cpuctx->hrtimer_active = 0; | |
1145 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1146 | |
4cfafd30 | 1147 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1148 | } |
1149 | ||
272325c4 | 1150 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1151 | { |
272325c4 | 1152 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1153 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1154 | u64 interval; |
9e630205 SE |
1155 | |
1156 | /* no multiplexing needed for SW PMU */ | |
1157 | if (pmu->task_ctx_nr == perf_sw_context) | |
1158 | return; | |
1159 | ||
62b85639 SE |
1160 | /* |
1161 | * check default is sane, if not set then force to | |
1162 | * default interval (1/tick) | |
1163 | */ | |
272325c4 PZ |
1164 | interval = pmu->hrtimer_interval_ms; |
1165 | if (interval < 1) | |
1166 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1167 | |
272325c4 | 1168 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1169 | |
4cfafd30 | 1170 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1171 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1172 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1173 | } |
1174 | ||
272325c4 | 1175 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1176 | { |
272325c4 | 1177 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1178 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1179 | unsigned long flags; |
9e630205 SE |
1180 | |
1181 | /* not for SW PMU */ | |
1182 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1183 | return 0; |
9e630205 | 1184 | |
4cfafd30 PZ |
1185 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1186 | if (!cpuctx->hrtimer_active) { | |
1187 | cpuctx->hrtimer_active = 1; | |
1188 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1189 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1190 | } |
1191 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1192 | |
272325c4 | 1193 | return 0; |
9e630205 SE |
1194 | } |
1195 | ||
33696fc0 | 1196 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1197 | { |
33696fc0 PZ |
1198 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1199 | if (!(*count)++) | |
1200 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1201 | } |
9e35ad38 | 1202 | |
33696fc0 | 1203 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1204 | { |
33696fc0 PZ |
1205 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1206 | if (!--(*count)) | |
1207 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1208 | } |
9e35ad38 | 1209 | |
2fde4f94 | 1210 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1211 | |
1212 | /* | |
2fde4f94 MR |
1213 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1214 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1215 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1216 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1217 | */ |
2fde4f94 | 1218 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1219 | { |
2fde4f94 | 1220 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1221 | |
16444645 | 1222 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1223 | |
2fde4f94 MR |
1224 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1225 | ||
1226 | list_add(&ctx->active_ctx_list, head); | |
1227 | } | |
1228 | ||
1229 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1230 | { | |
16444645 | 1231 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1232 | |
1233 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1234 | ||
1235 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1236 | } |
9e35ad38 | 1237 | |
cdd6c482 | 1238 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1239 | { |
8c94abbb | 1240 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1241 | } |
1242 | ||
ff9ff926 KL |
1243 | static void *alloc_task_ctx_data(struct pmu *pmu) |
1244 | { | |
217c2a63 KL |
1245 | if (pmu->task_ctx_cache) |
1246 | return kmem_cache_zalloc(pmu->task_ctx_cache, GFP_KERNEL); | |
1247 | ||
5a09928d | 1248 | return NULL; |
ff9ff926 KL |
1249 | } |
1250 | ||
1251 | static void free_task_ctx_data(struct pmu *pmu, void *task_ctx_data) | |
1252 | { | |
217c2a63 KL |
1253 | if (pmu->task_ctx_cache && task_ctx_data) |
1254 | kmem_cache_free(pmu->task_ctx_cache, task_ctx_data); | |
ff9ff926 KL |
1255 | } |
1256 | ||
4af57ef2 YZ |
1257 | static void free_ctx(struct rcu_head *head) |
1258 | { | |
1259 | struct perf_event_context *ctx; | |
1260 | ||
1261 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
ff9ff926 | 1262 | free_task_ctx_data(ctx->pmu, ctx->task_ctx_data); |
4af57ef2 YZ |
1263 | kfree(ctx); |
1264 | } | |
1265 | ||
cdd6c482 | 1266 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1267 | { |
8c94abbb | 1268 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1269 | if (ctx->parent_ctx) |
1270 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1271 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1272 | put_task_struct(ctx->task); |
4af57ef2 | 1273 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1274 | } |
a63eaf34 PM |
1275 | } |
1276 | ||
f63a8daa PZ |
1277 | /* |
1278 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1279 | * perf_pmu_migrate_context() we need some magic. | |
1280 | * | |
1281 | * Those places that change perf_event::ctx will hold both | |
1282 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1283 | * | |
8b10c5e2 PZ |
1284 | * Lock ordering is by mutex address. There are two other sites where |
1285 | * perf_event_context::mutex nests and those are: | |
1286 | * | |
1287 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1288 | * perf_event_exit_event() |
1289 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1290 | * |
1291 | * - perf_event_init_context() [ parent, 0 ] | |
1292 | * inherit_task_group() | |
1293 | * inherit_group() | |
1294 | * inherit_event() | |
1295 | * perf_event_alloc() | |
1296 | * perf_init_event() | |
1297 | * perf_try_init_event() [ child , 1 ] | |
1298 | * | |
1299 | * While it appears there is an obvious deadlock here -- the parent and child | |
1300 | * nesting levels are inverted between the two. This is in fact safe because | |
1301 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1302 | * spawning task cannot (yet) exit. | |
1303 | * | |
c034f48e | 1304 | * But remember that these are parent<->child context relations, and |
8b10c5e2 PZ |
1305 | * migration does not affect children, therefore these two orderings should not |
1306 | * interact. | |
f63a8daa PZ |
1307 | * |
1308 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1309 | * because the sys_perf_event_open() case will install a new event and break | |
1310 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1311 | * concerned with cpuctx and that doesn't have children. | |
1312 | * | |
1313 | * The places that change perf_event::ctx will issue: | |
1314 | * | |
1315 | * perf_remove_from_context(); | |
1316 | * synchronize_rcu(); | |
1317 | * perf_install_in_context(); | |
1318 | * | |
1319 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1320 | * quiesce the event, after which we can install it in the new location. This | |
1321 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1322 | * while in transit. Therefore all such accessors should also acquire | |
1323 | * perf_event_context::mutex to serialize against this. | |
1324 | * | |
1325 | * However; because event->ctx can change while we're waiting to acquire | |
1326 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1327 | * function. | |
1328 | * | |
1329 | * Lock order: | |
f7cfd871 | 1330 | * exec_update_lock |
f63a8daa PZ |
1331 | * task_struct::perf_event_mutex |
1332 | * perf_event_context::mutex | |
f63a8daa | 1333 | * perf_event::child_mutex; |
07c4a776 | 1334 | * perf_event_context::lock |
f63a8daa | 1335 | * perf_event::mmap_mutex |
c1e8d7c6 | 1336 | * mmap_lock |
18736eef | 1337 | * perf_addr_filters_head::lock |
82d94856 PZ |
1338 | * |
1339 | * cpu_hotplug_lock | |
1340 | * pmus_lock | |
1341 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1342 | */ |
a83fe28e PZ |
1343 | static struct perf_event_context * |
1344 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1345 | { |
1346 | struct perf_event_context *ctx; | |
1347 | ||
1348 | again: | |
1349 | rcu_read_lock(); | |
6aa7de05 | 1350 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1351 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1352 | rcu_read_unlock(); |
1353 | goto again; | |
1354 | } | |
1355 | rcu_read_unlock(); | |
1356 | ||
a83fe28e | 1357 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1358 | if (event->ctx != ctx) { |
1359 | mutex_unlock(&ctx->mutex); | |
1360 | put_ctx(ctx); | |
1361 | goto again; | |
1362 | } | |
1363 | ||
1364 | return ctx; | |
1365 | } | |
1366 | ||
a83fe28e PZ |
1367 | static inline struct perf_event_context * |
1368 | perf_event_ctx_lock(struct perf_event *event) | |
1369 | { | |
1370 | return perf_event_ctx_lock_nested(event, 0); | |
1371 | } | |
1372 | ||
f63a8daa PZ |
1373 | static void perf_event_ctx_unlock(struct perf_event *event, |
1374 | struct perf_event_context *ctx) | |
1375 | { | |
1376 | mutex_unlock(&ctx->mutex); | |
1377 | put_ctx(ctx); | |
1378 | } | |
1379 | ||
211de6eb PZ |
1380 | /* |
1381 | * This must be done under the ctx->lock, such as to serialize against | |
1382 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1383 | * calling scheduler related locks and ctx->lock nests inside those. | |
1384 | */ | |
1385 | static __must_check struct perf_event_context * | |
1386 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1387 | { |
211de6eb PZ |
1388 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1389 | ||
1390 | lockdep_assert_held(&ctx->lock); | |
1391 | ||
1392 | if (parent_ctx) | |
71a851b4 | 1393 | ctx->parent_ctx = NULL; |
5a3126d4 | 1394 | ctx->generation++; |
211de6eb PZ |
1395 | |
1396 | return parent_ctx; | |
71a851b4 PZ |
1397 | } |
1398 | ||
1d953111 ON |
1399 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1400 | enum pid_type type) | |
6844c09d | 1401 | { |
1d953111 | 1402 | u32 nr; |
6844c09d ACM |
1403 | /* |
1404 | * only top level events have the pid namespace they were created in | |
1405 | */ | |
1406 | if (event->parent) | |
1407 | event = event->parent; | |
1408 | ||
1d953111 ON |
1409 | nr = __task_pid_nr_ns(p, type, event->ns); |
1410 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1411 | if (!nr && !pid_alive(p)) | |
1412 | nr = -1; | |
1413 | return nr; | |
6844c09d ACM |
1414 | } |
1415 | ||
1d953111 | 1416 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1417 | { |
6883f81a | 1418 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1419 | } |
6844c09d | 1420 | |
1d953111 ON |
1421 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1422 | { | |
1423 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1424 | } |
1425 | ||
7f453c24 | 1426 | /* |
cdd6c482 | 1427 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1428 | * to userspace. |
1429 | */ | |
cdd6c482 | 1430 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1431 | { |
cdd6c482 | 1432 | u64 id = event->id; |
7f453c24 | 1433 | |
cdd6c482 IM |
1434 | if (event->parent) |
1435 | id = event->parent->id; | |
7f453c24 PZ |
1436 | |
1437 | return id; | |
1438 | } | |
1439 | ||
25346b93 | 1440 | /* |
cdd6c482 | 1441 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1442 | * |
c034f48e | 1443 | * This has to cope with the fact that until it is locked, |
25346b93 PM |
1444 | * the context could get moved to another task. |
1445 | */ | |
cdd6c482 | 1446 | static struct perf_event_context * |
8dc85d54 | 1447 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1448 | { |
cdd6c482 | 1449 | struct perf_event_context *ctx; |
25346b93 | 1450 | |
9ed6060d | 1451 | retry: |
058ebd0e PZ |
1452 | /* |
1453 | * One of the few rules of preemptible RCU is that one cannot do | |
1454 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1455 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1456 | * rcu_read_unlock_special(). |
1457 | * | |
1458 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1459 | * side critical section has interrupts disabled. |
058ebd0e | 1460 | */ |
2fd59077 | 1461 | local_irq_save(*flags); |
058ebd0e | 1462 | rcu_read_lock(); |
8dc85d54 | 1463 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1464 | if (ctx) { |
1465 | /* | |
1466 | * If this context is a clone of another, it might | |
1467 | * get swapped for another underneath us by | |
cdd6c482 | 1468 | * perf_event_task_sched_out, though the |
25346b93 PM |
1469 | * rcu_read_lock() protects us from any context |
1470 | * getting freed. Lock the context and check if it | |
1471 | * got swapped before we could get the lock, and retry | |
1472 | * if so. If we locked the right context, then it | |
1473 | * can't get swapped on us any more. | |
1474 | */ | |
2fd59077 | 1475 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1476 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1477 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1478 | rcu_read_unlock(); |
2fd59077 | 1479 | local_irq_restore(*flags); |
25346b93 PM |
1480 | goto retry; |
1481 | } | |
b49a9e7e | 1482 | |
63b6da39 | 1483 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1484 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1485 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1486 | ctx = NULL; |
828b6f0e PZ |
1487 | } else { |
1488 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1489 | } |
25346b93 PM |
1490 | } |
1491 | rcu_read_unlock(); | |
2fd59077 PM |
1492 | if (!ctx) |
1493 | local_irq_restore(*flags); | |
25346b93 PM |
1494 | return ctx; |
1495 | } | |
1496 | ||
1497 | /* | |
1498 | * Get the context for a task and increment its pin_count so it | |
1499 | * can't get swapped to another task. This also increments its | |
1500 | * reference count so that the context can't get freed. | |
1501 | */ | |
8dc85d54 PZ |
1502 | static struct perf_event_context * |
1503 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1504 | { |
cdd6c482 | 1505 | struct perf_event_context *ctx; |
25346b93 PM |
1506 | unsigned long flags; |
1507 | ||
8dc85d54 | 1508 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1509 | if (ctx) { |
1510 | ++ctx->pin_count; | |
e625cce1 | 1511 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1512 | } |
1513 | return ctx; | |
1514 | } | |
1515 | ||
cdd6c482 | 1516 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1517 | { |
1518 | unsigned long flags; | |
1519 | ||
e625cce1 | 1520 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1521 | --ctx->pin_count; |
e625cce1 | 1522 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1523 | } |
1524 | ||
f67218c3 PZ |
1525 | /* |
1526 | * Update the record of the current time in a context. | |
1527 | */ | |
1528 | static void update_context_time(struct perf_event_context *ctx) | |
1529 | { | |
1530 | u64 now = perf_clock(); | |
1531 | ||
1532 | ctx->time += now - ctx->timestamp; | |
1533 | ctx->timestamp = now; | |
1534 | } | |
1535 | ||
4158755d SE |
1536 | static u64 perf_event_time(struct perf_event *event) |
1537 | { | |
1538 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1539 | |
1540 | if (is_cgroup_event(event)) | |
1541 | return perf_cgroup_event_time(event); | |
1542 | ||
4158755d SE |
1543 | return ctx ? ctx->time : 0; |
1544 | } | |
1545 | ||
487f05e1 AS |
1546 | static enum event_type_t get_event_type(struct perf_event *event) |
1547 | { | |
1548 | struct perf_event_context *ctx = event->ctx; | |
1549 | enum event_type_t event_type; | |
1550 | ||
1551 | lockdep_assert_held(&ctx->lock); | |
1552 | ||
3bda69c1 AS |
1553 | /* |
1554 | * It's 'group type', really, because if our group leader is | |
1555 | * pinned, so are we. | |
1556 | */ | |
1557 | if (event->group_leader != event) | |
1558 | event = event->group_leader; | |
1559 | ||
487f05e1 AS |
1560 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1561 | if (!ctx->task) | |
1562 | event_type |= EVENT_CPU; | |
1563 | ||
1564 | return event_type; | |
1565 | } | |
1566 | ||
8e1a2031 | 1567 | /* |
161c85fa | 1568 | * Helper function to initialize event group nodes. |
8e1a2031 | 1569 | */ |
161c85fa | 1570 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1571 | { |
1572 | RB_CLEAR_NODE(&event->group_node); | |
1573 | event->group_index = 0; | |
1574 | } | |
1575 | ||
1576 | /* | |
1577 | * Extract pinned or flexible groups from the context | |
161c85fa | 1578 | * based on event attrs bits. |
8e1a2031 AB |
1579 | */ |
1580 | static struct perf_event_groups * | |
1581 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1582 | { |
1583 | if (event->attr.pinned) | |
1584 | return &ctx->pinned_groups; | |
1585 | else | |
1586 | return &ctx->flexible_groups; | |
1587 | } | |
1588 | ||
8e1a2031 | 1589 | /* |
161c85fa | 1590 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1591 | */ |
161c85fa | 1592 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1593 | { |
1594 | groups->tree = RB_ROOT; | |
1595 | groups->index = 0; | |
1596 | } | |
1597 | ||
a3b89864 PZ |
1598 | static inline struct cgroup *event_cgroup(const struct perf_event *event) |
1599 | { | |
1600 | struct cgroup *cgroup = NULL; | |
1601 | ||
1602 | #ifdef CONFIG_CGROUP_PERF | |
1603 | if (event->cgrp) | |
1604 | cgroup = event->cgrp->css.cgroup; | |
1605 | #endif | |
1606 | ||
1607 | return cgroup; | |
1608 | } | |
1609 | ||
8e1a2031 AB |
1610 | /* |
1611 | * Compare function for event groups; | |
161c85fa PZ |
1612 | * |
1613 | * Implements complex key that first sorts by CPU and then by virtual index | |
1614 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1615 | */ |
a3b89864 PZ |
1616 | static __always_inline int |
1617 | perf_event_groups_cmp(const int left_cpu, const struct cgroup *left_cgroup, | |
1618 | const u64 left_group_index, const struct perf_event *right) | |
8e1a2031 | 1619 | { |
a3b89864 PZ |
1620 | if (left_cpu < right->cpu) |
1621 | return -1; | |
1622 | if (left_cpu > right->cpu) | |
1623 | return 1; | |
161c85fa | 1624 | |
95ed6c70 | 1625 | #ifdef CONFIG_CGROUP_PERF |
a3b89864 PZ |
1626 | { |
1627 | const struct cgroup *right_cgroup = event_cgroup(right); | |
1628 | ||
1629 | if (left_cgroup != right_cgroup) { | |
1630 | if (!left_cgroup) { | |
1631 | /* | |
1632 | * Left has no cgroup but right does, no | |
1633 | * cgroups come first. | |
1634 | */ | |
1635 | return -1; | |
1636 | } | |
1637 | if (!right_cgroup) { | |
1638 | /* | |
1639 | * Right has no cgroup but left does, no | |
1640 | * cgroups come first. | |
1641 | */ | |
1642 | return 1; | |
1643 | } | |
1644 | /* Two dissimilar cgroups, order by id. */ | |
1645 | if (cgroup_id(left_cgroup) < cgroup_id(right_cgroup)) | |
1646 | return -1; | |
1647 | ||
1648 | return 1; | |
95ed6c70 | 1649 | } |
95ed6c70 IR |
1650 | } |
1651 | #endif | |
1652 | ||
a3b89864 PZ |
1653 | if (left_group_index < right->group_index) |
1654 | return -1; | |
1655 | if (left_group_index > right->group_index) | |
1656 | return 1; | |
1657 | ||
1658 | return 0; | |
1659 | } | |
161c85fa | 1660 | |
a3b89864 PZ |
1661 | #define __node_2_pe(node) \ |
1662 | rb_entry((node), struct perf_event, group_node) | |
1663 | ||
1664 | static inline bool __group_less(struct rb_node *a, const struct rb_node *b) | |
1665 | { | |
1666 | struct perf_event *e = __node_2_pe(a); | |
1667 | return perf_event_groups_cmp(e->cpu, event_cgroup(e), e->group_index, | |
1668 | __node_2_pe(b)) < 0; | |
1669 | } | |
1670 | ||
1671 | struct __group_key { | |
1672 | int cpu; | |
1673 | struct cgroup *cgroup; | |
1674 | }; | |
1675 | ||
1676 | static inline int __group_cmp(const void *key, const struct rb_node *node) | |
1677 | { | |
1678 | const struct __group_key *a = key; | |
1679 | const struct perf_event *b = __node_2_pe(node); | |
1680 | ||
1681 | /* partial/subtree match: @cpu, @cgroup; ignore: @group_index */ | |
1682 | return perf_event_groups_cmp(a->cpu, a->cgroup, b->group_index, b); | |
8e1a2031 AB |
1683 | } |
1684 | ||
1685 | /* | |
161c85fa PZ |
1686 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1687 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1688 | * subtree. | |
8e1a2031 AB |
1689 | */ |
1690 | static void | |
1691 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1692 | struct perf_event *event) |
8e1a2031 | 1693 | { |
8e1a2031 AB |
1694 | event->group_index = ++groups->index; |
1695 | ||
a3b89864 | 1696 | rb_add(&event->group_node, &groups->tree, __group_less); |
8e1a2031 AB |
1697 | } |
1698 | ||
1699 | /* | |
161c85fa | 1700 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1701 | */ |
1702 | static void | |
1703 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1704 | { | |
1705 | struct perf_event_groups *groups; | |
1706 | ||
1707 | groups = get_event_groups(event, ctx); | |
1708 | perf_event_groups_insert(groups, event); | |
1709 | } | |
1710 | ||
1711 | /* | |
161c85fa | 1712 | * Delete a group from a tree. |
8e1a2031 AB |
1713 | */ |
1714 | static void | |
1715 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1716 | struct perf_event *event) |
8e1a2031 | 1717 | { |
161c85fa PZ |
1718 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1719 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1720 | |
161c85fa | 1721 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1722 | init_event_group(event); |
1723 | } | |
1724 | ||
1725 | /* | |
161c85fa | 1726 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1727 | */ |
1728 | static void | |
1729 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1730 | { | |
1731 | struct perf_event_groups *groups; | |
1732 | ||
1733 | groups = get_event_groups(event, ctx); | |
1734 | perf_event_groups_delete(groups, event); | |
1735 | } | |
1736 | ||
1737 | /* | |
95ed6c70 | 1738 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1739 | */ |
1740 | static struct perf_event * | |
95ed6c70 IR |
1741 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1742 | struct cgroup *cgrp) | |
8e1a2031 | 1743 | { |
a3b89864 PZ |
1744 | struct __group_key key = { |
1745 | .cpu = cpu, | |
1746 | .cgroup = cgrp, | |
1747 | }; | |
1748 | struct rb_node *node; | |
95ed6c70 | 1749 | |
a3b89864 PZ |
1750 | node = rb_find_first(&key, &groups->tree, __group_cmp); |
1751 | if (node) | |
1752 | return __node_2_pe(node); | |
8e1a2031 | 1753 | |
a3b89864 | 1754 | return NULL; |
8e1a2031 AB |
1755 | } |
1756 | ||
1cac7b1a PZ |
1757 | /* |
1758 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1759 | */ | |
1760 | static struct perf_event * | |
1761 | perf_event_groups_next(struct perf_event *event) | |
1762 | { | |
a3b89864 PZ |
1763 | struct __group_key key = { |
1764 | .cpu = event->cpu, | |
1765 | .cgroup = event_cgroup(event), | |
1766 | }; | |
1767 | struct rb_node *next; | |
1cac7b1a | 1768 | |
a3b89864 PZ |
1769 | next = rb_next_match(&key, &event->group_node, __group_cmp); |
1770 | if (next) | |
1771 | return __node_2_pe(next); | |
95ed6c70 | 1772 | |
a3b89864 | 1773 | return NULL; |
1cac7b1a PZ |
1774 | } |
1775 | ||
8e1a2031 | 1776 | /* |
161c85fa | 1777 | * Iterate through the whole groups tree. |
8e1a2031 | 1778 | */ |
6e6804d2 PZ |
1779 | #define perf_event_groups_for_each(event, groups) \ |
1780 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1781 | typeof(*event), group_node); event; \ | |
1782 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1783 | typeof(*event), group_node)) | |
8e1a2031 | 1784 | |
fccc714b | 1785 | /* |
788faab7 | 1786 | * Add an event from the lists for its context. |
fccc714b PZ |
1787 | * Must be called with ctx->mutex and ctx->lock held. |
1788 | */ | |
04289bb9 | 1789 | static void |
cdd6c482 | 1790 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1791 | { |
c994d613 PZ |
1792 | lockdep_assert_held(&ctx->lock); |
1793 | ||
8a49542c PZ |
1794 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1795 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1796 | |
0d3d73aa PZ |
1797 | event->tstamp = perf_event_time(event); |
1798 | ||
04289bb9 | 1799 | /* |
8a49542c PZ |
1800 | * If we're a stand alone event or group leader, we go to the context |
1801 | * list, group events are kept attached to the group so that | |
1802 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1803 | */ |
8a49542c | 1804 | if (event->group_leader == event) { |
4ff6a8de | 1805 | event->group_caps = event->event_caps; |
8e1a2031 | 1806 | add_event_to_groups(event, ctx); |
5c148194 | 1807 | } |
592903cd | 1808 | |
cdd6c482 IM |
1809 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1810 | ctx->nr_events++; | |
1811 | if (event->attr.inherit_stat) | |
bfbd3381 | 1812 | ctx->nr_stat++; |
5a3126d4 | 1813 | |
33238c50 PZ |
1814 | if (event->state > PERF_EVENT_STATE_OFF) |
1815 | perf_cgroup_event_enable(event, ctx); | |
1816 | ||
5a3126d4 | 1817 | ctx->generation++; |
04289bb9 IM |
1818 | } |
1819 | ||
0231bb53 JO |
1820 | /* |
1821 | * Initialize event state based on the perf_event_attr::disabled. | |
1822 | */ | |
1823 | static inline void perf_event__state_init(struct perf_event *event) | |
1824 | { | |
1825 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1826 | PERF_EVENT_STATE_INACTIVE; | |
1827 | } | |
1828 | ||
a723968c | 1829 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1830 | { |
1831 | int entry = sizeof(u64); /* value */ | |
1832 | int size = 0; | |
1833 | int nr = 1; | |
1834 | ||
1835 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1836 | size += sizeof(u64); | |
1837 | ||
1838 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1839 | size += sizeof(u64); | |
1840 | ||
1841 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1842 | entry += sizeof(u64); | |
1843 | ||
1844 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1845 | nr += nr_siblings; |
c320c7b7 ACM |
1846 | size += sizeof(u64); |
1847 | } | |
1848 | ||
1849 | size += entry * nr; | |
1850 | event->read_size = size; | |
1851 | } | |
1852 | ||
a723968c | 1853 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1854 | { |
1855 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1856 | u16 size = 0; |
1857 | ||
c320c7b7 ACM |
1858 | if (sample_type & PERF_SAMPLE_IP) |
1859 | size += sizeof(data->ip); | |
1860 | ||
6844c09d ACM |
1861 | if (sample_type & PERF_SAMPLE_ADDR) |
1862 | size += sizeof(data->addr); | |
1863 | ||
1864 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1865 | size += sizeof(data->period); | |
1866 | ||
2a6c6b7d KL |
1867 | if (sample_type & PERF_SAMPLE_WEIGHT_TYPE) |
1868 | size += sizeof(data->weight.full); | |
c3feedf2 | 1869 | |
6844c09d ACM |
1870 | if (sample_type & PERF_SAMPLE_READ) |
1871 | size += event->read_size; | |
1872 | ||
d6be9ad6 SE |
1873 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1874 | size += sizeof(data->data_src.val); | |
1875 | ||
fdfbbd07 AK |
1876 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1877 | size += sizeof(data->txn); | |
1878 | ||
fc7ce9c7 KL |
1879 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1880 | size += sizeof(data->phys_addr); | |
1881 | ||
6546b19f NK |
1882 | if (sample_type & PERF_SAMPLE_CGROUP) |
1883 | size += sizeof(data->cgroup); | |
1884 | ||
8d97e718 KL |
1885 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
1886 | size += sizeof(data->data_page_size); | |
1887 | ||
995f088e SE |
1888 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
1889 | size += sizeof(data->code_page_size); | |
1890 | ||
6844c09d ACM |
1891 | event->header_size = size; |
1892 | } | |
1893 | ||
a723968c PZ |
1894 | /* |
1895 | * Called at perf_event creation and when events are attached/detached from a | |
1896 | * group. | |
1897 | */ | |
1898 | static void perf_event__header_size(struct perf_event *event) | |
1899 | { | |
1900 | __perf_event_read_size(event, | |
1901 | event->group_leader->nr_siblings); | |
1902 | __perf_event_header_size(event, event->attr.sample_type); | |
1903 | } | |
1904 | ||
6844c09d ACM |
1905 | static void perf_event__id_header_size(struct perf_event *event) |
1906 | { | |
1907 | struct perf_sample_data *data; | |
1908 | u64 sample_type = event->attr.sample_type; | |
1909 | u16 size = 0; | |
1910 | ||
c320c7b7 ACM |
1911 | if (sample_type & PERF_SAMPLE_TID) |
1912 | size += sizeof(data->tid_entry); | |
1913 | ||
1914 | if (sample_type & PERF_SAMPLE_TIME) | |
1915 | size += sizeof(data->time); | |
1916 | ||
ff3d527c AH |
1917 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1918 | size += sizeof(data->id); | |
1919 | ||
c320c7b7 ACM |
1920 | if (sample_type & PERF_SAMPLE_ID) |
1921 | size += sizeof(data->id); | |
1922 | ||
1923 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1924 | size += sizeof(data->stream_id); | |
1925 | ||
1926 | if (sample_type & PERF_SAMPLE_CPU) | |
1927 | size += sizeof(data->cpu_entry); | |
1928 | ||
6844c09d | 1929 | event->id_header_size = size; |
c320c7b7 ACM |
1930 | } |
1931 | ||
a723968c PZ |
1932 | static bool perf_event_validate_size(struct perf_event *event) |
1933 | { | |
1934 | /* | |
1935 | * The values computed here will be over-written when we actually | |
1936 | * attach the event. | |
1937 | */ | |
1938 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1939 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1940 | perf_event__id_header_size(event); | |
1941 | ||
1942 | /* | |
1943 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1944 | * Conservative limit to allow for callchains and other variable fields. | |
1945 | */ | |
1946 | if (event->read_size + event->header_size + | |
1947 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1948 | return false; | |
1949 | ||
1950 | return true; | |
1951 | } | |
1952 | ||
8a49542c PZ |
1953 | static void perf_group_attach(struct perf_event *event) |
1954 | { | |
c320c7b7 | 1955 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1956 | |
a76a82a3 PZ |
1957 | lockdep_assert_held(&event->ctx->lock); |
1958 | ||
74c3337c PZ |
1959 | /* |
1960 | * We can have double attach due to group movement in perf_event_open. | |
1961 | */ | |
1962 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1963 | return; | |
1964 | ||
8a49542c PZ |
1965 | event->attach_state |= PERF_ATTACH_GROUP; |
1966 | ||
1967 | if (group_leader == event) | |
1968 | return; | |
1969 | ||
652884fe PZ |
1970 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1971 | ||
4ff6a8de | 1972 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1973 | |
8343aae6 | 1974 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1975 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1976 | |
1977 | perf_event__header_size(group_leader); | |
1978 | ||
edb39592 | 1979 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1980 | perf_event__header_size(pos); |
8a49542c PZ |
1981 | } |
1982 | ||
a63eaf34 | 1983 | /* |
788faab7 | 1984 | * Remove an event from the lists for its context. |
fccc714b | 1985 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1986 | */ |
04289bb9 | 1987 | static void |
cdd6c482 | 1988 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1989 | { |
652884fe PZ |
1990 | WARN_ON_ONCE(event->ctx != ctx); |
1991 | lockdep_assert_held(&ctx->lock); | |
1992 | ||
8a49542c PZ |
1993 | /* |
1994 | * We can have double detach due to exit/hot-unplug + close. | |
1995 | */ | |
1996 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1997 | return; |
8a49542c PZ |
1998 | |
1999 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
2000 | ||
cdd6c482 IM |
2001 | ctx->nr_events--; |
2002 | if (event->attr.inherit_stat) | |
bfbd3381 | 2003 | ctx->nr_stat--; |
8bc20959 | 2004 | |
cdd6c482 | 2005 | list_del_rcu(&event->event_entry); |
04289bb9 | 2006 | |
8a49542c | 2007 | if (event->group_leader == event) |
8e1a2031 | 2008 | del_event_from_groups(event, ctx); |
5c148194 | 2009 | |
b2e74a26 SE |
2010 | /* |
2011 | * If event was in error state, then keep it | |
2012 | * that way, otherwise bogus counts will be | |
2013 | * returned on read(). The only way to get out | |
2014 | * of error state is by explicit re-enabling | |
2015 | * of the event | |
2016 | */ | |
33238c50 PZ |
2017 | if (event->state > PERF_EVENT_STATE_OFF) { |
2018 | perf_cgroup_event_disable(event, ctx); | |
0d3d73aa | 2019 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
33238c50 | 2020 | } |
5a3126d4 PZ |
2021 | |
2022 | ctx->generation++; | |
050735b0 PZ |
2023 | } |
2024 | ||
ab43762e AS |
2025 | static int |
2026 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2027 | { | |
2028 | if (!has_aux(aux_event)) | |
2029 | return 0; | |
2030 | ||
2031 | if (!event->pmu->aux_output_match) | |
2032 | return 0; | |
2033 | ||
2034 | return event->pmu->aux_output_match(aux_event); | |
2035 | } | |
2036 | ||
2037 | static void put_event(struct perf_event *event); | |
2038 | static void event_sched_out(struct perf_event *event, | |
2039 | struct perf_cpu_context *cpuctx, | |
2040 | struct perf_event_context *ctx); | |
2041 | ||
2042 | static void perf_put_aux_event(struct perf_event *event) | |
2043 | { | |
2044 | struct perf_event_context *ctx = event->ctx; | |
2045 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2046 | struct perf_event *iter; | |
2047 | ||
2048 | /* | |
2049 | * If event uses aux_event tear down the link | |
2050 | */ | |
2051 | if (event->aux_event) { | |
2052 | iter = event->aux_event; | |
2053 | event->aux_event = NULL; | |
2054 | put_event(iter); | |
2055 | return; | |
2056 | } | |
2057 | ||
2058 | /* | |
2059 | * If the event is an aux_event, tear down all links to | |
2060 | * it from other events. | |
2061 | */ | |
2062 | for_each_sibling_event(iter, event->group_leader) { | |
2063 | if (iter->aux_event != event) | |
2064 | continue; | |
2065 | ||
2066 | iter->aux_event = NULL; | |
2067 | put_event(event); | |
2068 | ||
2069 | /* | |
2070 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2071 | * state so that we don't try to schedule it again. Note | |
2072 | * that perf_event_enable() will clear the ERROR status. | |
2073 | */ | |
2074 | event_sched_out(iter, cpuctx, ctx); | |
2075 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2076 | } | |
2077 | } | |
2078 | ||
a4faf00d AS |
2079 | static bool perf_need_aux_event(struct perf_event *event) |
2080 | { | |
2081 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2082 | } | |
2083 | ||
ab43762e AS |
2084 | static int perf_get_aux_event(struct perf_event *event, |
2085 | struct perf_event *group_leader) | |
2086 | { | |
2087 | /* | |
2088 | * Our group leader must be an aux event if we want to be | |
2089 | * an aux_output. This way, the aux event will precede its | |
2090 | * aux_output events in the group, and therefore will always | |
2091 | * schedule first. | |
2092 | */ | |
2093 | if (!group_leader) | |
2094 | return 0; | |
2095 | ||
a4faf00d AS |
2096 | /* |
2097 | * aux_output and aux_sample_size are mutually exclusive. | |
2098 | */ | |
2099 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2100 | return 0; | |
2101 | ||
2102 | if (event->attr.aux_output && | |
2103 | !perf_aux_output_match(event, group_leader)) | |
2104 | return 0; | |
2105 | ||
2106 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2107 | return 0; |
2108 | ||
2109 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2110 | return 0; | |
2111 | ||
2112 | /* | |
2113 | * Link aux_outputs to their aux event; this is undone in | |
2114 | * perf_group_detach() by perf_put_aux_event(). When the | |
2115 | * group in torn down, the aux_output events loose their | |
2116 | * link to the aux_event and can't schedule any more. | |
2117 | */ | |
2118 | event->aux_event = group_leader; | |
2119 | ||
2120 | return 1; | |
2121 | } | |
2122 | ||
ab6f824c PZ |
2123 | static inline struct list_head *get_event_list(struct perf_event *event) |
2124 | { | |
2125 | struct perf_event_context *ctx = event->ctx; | |
2126 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2127 | } | |
2128 | ||
9f0c4fa1 KL |
2129 | /* |
2130 | * Events that have PERF_EV_CAP_SIBLING require being part of a group and | |
2131 | * cannot exist on their own, schedule them out and move them into the ERROR | |
2132 | * state. Also see _perf_event_enable(), it will not be able to recover | |
2133 | * this ERROR state. | |
2134 | */ | |
2135 | static inline void perf_remove_sibling_event(struct perf_event *event) | |
2136 | { | |
2137 | struct perf_event_context *ctx = event->ctx; | |
2138 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2139 | ||
2140 | event_sched_out(event, cpuctx, ctx); | |
2141 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2142 | } | |
2143 | ||
8a49542c | 2144 | static void perf_group_detach(struct perf_event *event) |
050735b0 | 2145 | { |
9f0c4fa1 | 2146 | struct perf_event *leader = event->group_leader; |
050735b0 | 2147 | struct perf_event *sibling, *tmp; |
6668128a | 2148 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2149 | |
6668128a | 2150 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2151 | |
8a49542c PZ |
2152 | /* |
2153 | * We can have double detach due to exit/hot-unplug + close. | |
2154 | */ | |
2155 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2156 | return; | |
2157 | ||
2158 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2159 | ||
ab43762e AS |
2160 | perf_put_aux_event(event); |
2161 | ||
8a49542c PZ |
2162 | /* |
2163 | * If this is a sibling, remove it from its group. | |
2164 | */ | |
9f0c4fa1 | 2165 | if (leader != event) { |
8343aae6 | 2166 | list_del_init(&event->sibling_list); |
8a49542c | 2167 | event->group_leader->nr_siblings--; |
c320c7b7 | 2168 | goto out; |
8a49542c PZ |
2169 | } |
2170 | ||
04289bb9 | 2171 | /* |
cdd6c482 IM |
2172 | * If this was a group event with sibling events then |
2173 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2174 | * to whatever list we are on. |
04289bb9 | 2175 | */ |
8343aae6 | 2176 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2177 | |
9f0c4fa1 KL |
2178 | if (sibling->event_caps & PERF_EV_CAP_SIBLING) |
2179 | perf_remove_sibling_event(sibling); | |
2180 | ||
04289bb9 | 2181 | sibling->group_leader = sibling; |
24868367 | 2182 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2183 | |
2184 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2185 | sibling->group_caps = event->group_caps; |
652884fe | 2186 | |
8e1a2031 | 2187 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2188 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2189 | |
ab6f824c PZ |
2190 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2191 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2192 | } |
2193 | ||
652884fe | 2194 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2195 | } |
c320c7b7 ACM |
2196 | |
2197 | out: | |
9f0c4fa1 | 2198 | for_each_sibling_event(tmp, leader) |
c320c7b7 | 2199 | perf_event__header_size(tmp); |
9f0c4fa1 KL |
2200 | |
2201 | perf_event__header_size(leader); | |
04289bb9 IM |
2202 | } |
2203 | ||
ef54c1a4 PZ |
2204 | static void sync_child_event(struct perf_event *child_event); |
2205 | ||
2206 | static void perf_child_detach(struct perf_event *event) | |
2207 | { | |
2208 | struct perf_event *parent_event = event->parent; | |
2209 | ||
2210 | if (!(event->attach_state & PERF_ATTACH_CHILD)) | |
2211 | return; | |
2212 | ||
2213 | event->attach_state &= ~PERF_ATTACH_CHILD; | |
2214 | ||
2215 | if (WARN_ON_ONCE(!parent_event)) | |
2216 | return; | |
2217 | ||
2218 | lockdep_assert_held(&parent_event->child_mutex); | |
2219 | ||
2220 | sync_child_event(event); | |
2221 | list_del_init(&event->child_list); | |
2222 | } | |
2223 | ||
fadfe7be JO |
2224 | static bool is_orphaned_event(struct perf_event *event) |
2225 | { | |
a69b0ca4 | 2226 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2227 | } |
2228 | ||
2c81a647 | 2229 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2230 | { |
2231 | struct pmu *pmu = event->pmu; | |
2232 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2233 | } | |
2234 | ||
2c81a647 MR |
2235 | /* |
2236 | * Check whether we should attempt to schedule an event group based on | |
2237 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2238 | * potentially with a SW leader, so we must check all the filters, to | |
2239 | * determine whether a group is schedulable: | |
2240 | */ | |
2241 | static inline int pmu_filter_match(struct perf_event *event) | |
2242 | { | |
edb39592 | 2243 | struct perf_event *sibling; |
2c81a647 MR |
2244 | |
2245 | if (!__pmu_filter_match(event)) | |
2246 | return 0; | |
2247 | ||
edb39592 PZ |
2248 | for_each_sibling_event(sibling, event) { |
2249 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2250 | return 0; |
2251 | } | |
2252 | ||
2253 | return 1; | |
2254 | } | |
2255 | ||
fa66f07a SE |
2256 | static inline int |
2257 | event_filter_match(struct perf_event *event) | |
2258 | { | |
0b8f1e2e PZ |
2259 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2260 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2261 | } |
2262 | ||
9ffcfa6f SE |
2263 | static void |
2264 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2265 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2266 | struct perf_event_context *ctx) |
3b6f9e5c | 2267 | { |
0d3d73aa | 2268 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2269 | |
2270 | WARN_ON_ONCE(event->ctx != ctx); | |
2271 | lockdep_assert_held(&ctx->lock); | |
2272 | ||
cdd6c482 | 2273 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2274 | return; |
3b6f9e5c | 2275 | |
6668128a PZ |
2276 | /* |
2277 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2278 | * we can schedule events _OUT_ individually through things like | |
2279 | * __perf_remove_from_context(). | |
2280 | */ | |
2281 | list_del_init(&event->active_list); | |
2282 | ||
44377277 AS |
2283 | perf_pmu_disable(event->pmu); |
2284 | ||
28a967c3 PZ |
2285 | event->pmu->del(event, 0); |
2286 | event->oncpu = -1; | |
0d3d73aa | 2287 | |
1d54ad94 PZ |
2288 | if (READ_ONCE(event->pending_disable) >= 0) { |
2289 | WRITE_ONCE(event->pending_disable, -1); | |
33238c50 | 2290 | perf_cgroup_event_disable(event, ctx); |
0d3d73aa | 2291 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2292 | } |
0d3d73aa | 2293 | perf_event_set_state(event, state); |
3b6f9e5c | 2294 | |
cdd6c482 | 2295 | if (!is_software_event(event)) |
3b6f9e5c | 2296 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2297 | if (!--ctx->nr_active) |
2298 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2299 | if (event->attr.freq && event->attr.sample_freq) |
2300 | ctx->nr_freq--; | |
cdd6c482 | 2301 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2302 | cpuctx->exclusive = 0; |
44377277 AS |
2303 | |
2304 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2305 | } |
2306 | ||
d859e29f | 2307 | static void |
cdd6c482 | 2308 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2309 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2310 | struct perf_event_context *ctx) |
d859e29f | 2311 | { |
cdd6c482 | 2312 | struct perf_event *event; |
0d3d73aa PZ |
2313 | |
2314 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2315 | return; | |
d859e29f | 2316 | |
3f005e7d MR |
2317 | perf_pmu_disable(ctx->pmu); |
2318 | ||
cdd6c482 | 2319 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2320 | |
2321 | /* | |
2322 | * Schedule out siblings (if any): | |
2323 | */ | |
edb39592 | 2324 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2325 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2326 | |
3f005e7d | 2327 | perf_pmu_enable(ctx->pmu); |
d859e29f PM |
2328 | } |
2329 | ||
45a0e07a | 2330 | #define DETACH_GROUP 0x01UL |
ef54c1a4 | 2331 | #define DETACH_CHILD 0x02UL |
0017960f | 2332 | |
0793a61d | 2333 | /* |
cdd6c482 | 2334 | * Cross CPU call to remove a performance event |
0793a61d | 2335 | * |
cdd6c482 | 2336 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2337 | * remove it from the context list. |
2338 | */ | |
fae3fde6 PZ |
2339 | static void |
2340 | __perf_remove_from_context(struct perf_event *event, | |
2341 | struct perf_cpu_context *cpuctx, | |
2342 | struct perf_event_context *ctx, | |
2343 | void *info) | |
0793a61d | 2344 | { |
45a0e07a | 2345 | unsigned long flags = (unsigned long)info; |
0793a61d | 2346 | |
3c5c8711 PZ |
2347 | if (ctx->is_active & EVENT_TIME) { |
2348 | update_context_time(ctx); | |
2349 | update_cgrp_time_from_cpuctx(cpuctx); | |
2350 | } | |
2351 | ||
cdd6c482 | 2352 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2353 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2354 | perf_group_detach(event); |
ef54c1a4 PZ |
2355 | if (flags & DETACH_CHILD) |
2356 | perf_child_detach(event); | |
cdd6c482 | 2357 | list_del_event(event, ctx); |
39a43640 PZ |
2358 | |
2359 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2360 | ctx->is_active = 0; |
90c91dfb | 2361 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2362 | if (ctx->task) { |
2363 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2364 | cpuctx->task_ctx = NULL; | |
2365 | } | |
64ce3126 | 2366 | } |
0793a61d TG |
2367 | } |
2368 | ||
0793a61d | 2369 | /* |
cdd6c482 | 2370 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2371 | * |
cdd6c482 IM |
2372 | * If event->ctx is a cloned context, callers must make sure that |
2373 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2374 | * remains valid. This is OK when called from perf_release since |
2375 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2376 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2377 | * context has been detached from its task. |
0793a61d | 2378 | */ |
45a0e07a | 2379 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2380 | { |
a76a82a3 PZ |
2381 | struct perf_event_context *ctx = event->ctx; |
2382 | ||
2383 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2384 | |
a76a82a3 | 2385 | /* |
ef54c1a4 PZ |
2386 | * Because of perf_event_exit_task(), perf_remove_from_context() ought |
2387 | * to work in the face of TASK_TOMBSTONE, unlike every other | |
2388 | * event_function_call() user. | |
a76a82a3 | 2389 | */ |
ef54c1a4 PZ |
2390 | raw_spin_lock_irq(&ctx->lock); |
2391 | if (!ctx->is_active) { | |
2392 | __perf_remove_from_context(event, __get_cpu_context(ctx), | |
2393 | ctx, (void *)flags); | |
a76a82a3 | 2394 | raw_spin_unlock_irq(&ctx->lock); |
ef54c1a4 | 2395 | return; |
a76a82a3 | 2396 | } |
ef54c1a4 PZ |
2397 | raw_spin_unlock_irq(&ctx->lock); |
2398 | ||
2399 | event_function_call(event, __perf_remove_from_context, (void *)flags); | |
0793a61d TG |
2400 | } |
2401 | ||
d859e29f | 2402 | /* |
cdd6c482 | 2403 | * Cross CPU call to disable a performance event |
d859e29f | 2404 | */ |
fae3fde6 PZ |
2405 | static void __perf_event_disable(struct perf_event *event, |
2406 | struct perf_cpu_context *cpuctx, | |
2407 | struct perf_event_context *ctx, | |
2408 | void *info) | |
7b648018 | 2409 | { |
fae3fde6 PZ |
2410 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2411 | return; | |
7b648018 | 2412 | |
3c5c8711 PZ |
2413 | if (ctx->is_active & EVENT_TIME) { |
2414 | update_context_time(ctx); | |
2415 | update_cgrp_time_from_event(event); | |
2416 | } | |
2417 | ||
fae3fde6 PZ |
2418 | if (event == event->group_leader) |
2419 | group_sched_out(event, cpuctx, ctx); | |
2420 | else | |
2421 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2422 | |
2423 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
33238c50 | 2424 | perf_cgroup_event_disable(event, ctx); |
7b648018 PZ |
2425 | } |
2426 | ||
d859e29f | 2427 | /* |
788faab7 | 2428 | * Disable an event. |
c93f7669 | 2429 | * |
cdd6c482 IM |
2430 | * If event->ctx is a cloned context, callers must make sure that |
2431 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2432 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2433 | * perf_event_for_each_child or perf_event_for_each because they |
2434 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2435 | * goes to exit will block in perf_event_exit_event(). |
2436 | * | |
cdd6c482 | 2437 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2438 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2439 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2440 | */ |
f63a8daa | 2441 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2442 | { |
cdd6c482 | 2443 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2444 | |
e625cce1 | 2445 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2446 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2447 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2448 | return; |
53cfbf59 | 2449 | } |
e625cce1 | 2450 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2451 | |
fae3fde6 PZ |
2452 | event_function_call(event, __perf_event_disable, NULL); |
2453 | } | |
2454 | ||
2455 | void perf_event_disable_local(struct perf_event *event) | |
2456 | { | |
2457 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2458 | } |
f63a8daa PZ |
2459 | |
2460 | /* | |
2461 | * Strictly speaking kernel users cannot create groups and therefore this | |
2462 | * interface does not need the perf_event_ctx_lock() magic. | |
2463 | */ | |
2464 | void perf_event_disable(struct perf_event *event) | |
2465 | { | |
2466 | struct perf_event_context *ctx; | |
2467 | ||
2468 | ctx = perf_event_ctx_lock(event); | |
2469 | _perf_event_disable(event); | |
2470 | perf_event_ctx_unlock(event, ctx); | |
2471 | } | |
dcfce4a0 | 2472 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2473 | |
5aab90ce JO |
2474 | void perf_event_disable_inatomic(struct perf_event *event) |
2475 | { | |
1d54ad94 PZ |
2476 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2477 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2478 | irq_work_queue(&event->pending); |
2479 | } | |
2480 | ||
e5d1367f | 2481 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2482 | struct perf_event_context *ctx) |
e5d1367f SE |
2483 | { |
2484 | /* | |
2485 | * use the correct time source for the time snapshot | |
2486 | * | |
2487 | * We could get by without this by leveraging the | |
2488 | * fact that to get to this function, the caller | |
2489 | * has most likely already called update_context_time() | |
2490 | * and update_cgrp_time_xx() and thus both timestamp | |
2491 | * are identical (or very close). Given that tstamp is, | |
2492 | * already adjusted for cgroup, we could say that: | |
2493 | * tstamp - ctx->timestamp | |
2494 | * is equivalent to | |
2495 | * tstamp - cgrp->timestamp. | |
2496 | * | |
2497 | * Then, in perf_output_read(), the calculation would | |
2498 | * work with no changes because: | |
2499 | * - event is guaranteed scheduled in | |
2500 | * - no scheduled out in between | |
2501 | * - thus the timestamp would be the same | |
2502 | * | |
2503 | * But this is a bit hairy. | |
2504 | * | |
2505 | * So instead, we have an explicit cgroup call to remain | |
c034f48e | 2506 | * within the time source all along. We believe it |
e5d1367f SE |
2507 | * is cleaner and simpler to understand. |
2508 | */ | |
2509 | if (is_cgroup_event(event)) | |
0d3d73aa | 2510 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2511 | else |
0d3d73aa | 2512 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2513 | } |
2514 | ||
4fe757dd PZ |
2515 | #define MAX_INTERRUPTS (~0ULL) |
2516 | ||
2517 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2518 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2519 | |
235c7fc7 | 2520 | static int |
9ffcfa6f | 2521 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2522 | struct perf_cpu_context *cpuctx, |
6e37738a | 2523 | struct perf_event_context *ctx) |
235c7fc7 | 2524 | { |
44377277 | 2525 | int ret = 0; |
4158755d | 2526 | |
ab6f824c PZ |
2527 | WARN_ON_ONCE(event->ctx != ctx); |
2528 | ||
63342411 PZ |
2529 | lockdep_assert_held(&ctx->lock); |
2530 | ||
cdd6c482 | 2531 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2532 | return 0; |
2533 | ||
95ff4ca2 AS |
2534 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2535 | /* | |
0c1cbc18 PZ |
2536 | * Order event::oncpu write to happen before the ACTIVE state is |
2537 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2538 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2539 | */ |
2540 | smp_wmb(); | |
0d3d73aa | 2541 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2542 | |
2543 | /* | |
2544 | * Unthrottle events, since we scheduled we might have missed several | |
2545 | * ticks already, also for a heavily scheduling task there is little | |
2546 | * guarantee it'll get a tick in a timely manner. | |
2547 | */ | |
2548 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2549 | perf_log_throttle(event, 1); | |
2550 | event->hw.interrupts = 0; | |
2551 | } | |
2552 | ||
44377277 AS |
2553 | perf_pmu_disable(event->pmu); |
2554 | ||
0d3d73aa | 2555 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2556 | |
ec0d7729 AS |
2557 | perf_log_itrace_start(event); |
2558 | ||
a4eaf7f1 | 2559 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2560 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2561 | event->oncpu = -1; |
44377277 AS |
2562 | ret = -EAGAIN; |
2563 | goto out; | |
235c7fc7 IM |
2564 | } |
2565 | ||
cdd6c482 | 2566 | if (!is_software_event(event)) |
3b6f9e5c | 2567 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2568 | if (!ctx->nr_active++) |
2569 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2570 | if (event->attr.freq && event->attr.sample_freq) |
2571 | ctx->nr_freq++; | |
235c7fc7 | 2572 | |
cdd6c482 | 2573 | if (event->attr.exclusive) |
3b6f9e5c PM |
2574 | cpuctx->exclusive = 1; |
2575 | ||
44377277 AS |
2576 | out: |
2577 | perf_pmu_enable(event->pmu); | |
2578 | ||
2579 | return ret; | |
235c7fc7 IM |
2580 | } |
2581 | ||
6751b71e | 2582 | static int |
cdd6c482 | 2583 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2584 | struct perf_cpu_context *cpuctx, |
6e37738a | 2585 | struct perf_event_context *ctx) |
6751b71e | 2586 | { |
6bde9b6c | 2587 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2588 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2589 | |
cdd6c482 | 2590 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2591 | return 0; |
2592 | ||
fbbe0701 | 2593 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2594 | |
251ff2d4 PZ |
2595 | if (event_sched_in(group_event, cpuctx, ctx)) |
2596 | goto error; | |
6751b71e PM |
2597 | |
2598 | /* | |
2599 | * Schedule in siblings as one group (if any): | |
2600 | */ | |
edb39592 | 2601 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2602 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2603 | partial_group = event; |
6751b71e PM |
2604 | goto group_error; |
2605 | } | |
2606 | } | |
2607 | ||
9ffcfa6f | 2608 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2609 | return 0; |
9ffcfa6f | 2610 | |
6751b71e PM |
2611 | group_error: |
2612 | /* | |
2613 | * Groups can be scheduled in as one unit only, so undo any | |
2614 | * partial group before returning: | |
0d3d73aa | 2615 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2616 | */ |
edb39592 | 2617 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2618 | if (event == partial_group) |
0d3d73aa | 2619 | break; |
d7842da4 | 2620 | |
0d3d73aa | 2621 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2622 | } |
9ffcfa6f | 2623 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2624 | |
251ff2d4 | 2625 | error: |
ad5133b7 | 2626 | pmu->cancel_txn(pmu); |
6751b71e PM |
2627 | return -EAGAIN; |
2628 | } | |
2629 | ||
3b6f9e5c | 2630 | /* |
cdd6c482 | 2631 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2632 | */ |
cdd6c482 | 2633 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2634 | struct perf_cpu_context *cpuctx, |
2635 | int can_add_hw) | |
2636 | { | |
2637 | /* | |
cdd6c482 | 2638 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2639 | */ |
4ff6a8de | 2640 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2641 | return 1; |
2642 | /* | |
2643 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2644 | * events can go on. |
3b6f9e5c PM |
2645 | */ |
2646 | if (cpuctx->exclusive) | |
2647 | return 0; | |
2648 | /* | |
2649 | * If this group is exclusive and there are already | |
cdd6c482 | 2650 | * events on the CPU, it can't go on. |
3b6f9e5c | 2651 | */ |
1908dc91 | 2652 | if (event->attr.exclusive && !list_empty(get_event_list(event))) |
3b6f9e5c PM |
2653 | return 0; |
2654 | /* | |
2655 | * Otherwise, try to add it if all previous groups were able | |
2656 | * to go on. | |
2657 | */ | |
2658 | return can_add_hw; | |
2659 | } | |
2660 | ||
cdd6c482 IM |
2661 | static void add_event_to_ctx(struct perf_event *event, |
2662 | struct perf_event_context *ctx) | |
53cfbf59 | 2663 | { |
cdd6c482 | 2664 | list_add_event(event, ctx); |
8a49542c | 2665 | perf_group_attach(event); |
53cfbf59 PM |
2666 | } |
2667 | ||
bd2afa49 PZ |
2668 | static void ctx_sched_out(struct perf_event_context *ctx, |
2669 | struct perf_cpu_context *cpuctx, | |
2670 | enum event_type_t event_type); | |
2c29ef0f PZ |
2671 | static void |
2672 | ctx_sched_in(struct perf_event_context *ctx, | |
2673 | struct perf_cpu_context *cpuctx, | |
2674 | enum event_type_t event_type, | |
2675 | struct task_struct *task); | |
fe4b04fa | 2676 | |
bd2afa49 | 2677 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2678 | struct perf_event_context *ctx, |
2679 | enum event_type_t event_type) | |
bd2afa49 PZ |
2680 | { |
2681 | if (!cpuctx->task_ctx) | |
2682 | return; | |
2683 | ||
2684 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2685 | return; | |
2686 | ||
487f05e1 | 2687 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2688 | } |
2689 | ||
dce5855b PZ |
2690 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2691 | struct perf_event_context *ctx, | |
2692 | struct task_struct *task) | |
2693 | { | |
2694 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2695 | if (ctx) | |
2696 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2697 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2698 | if (ctx) | |
2699 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2700 | } | |
2701 | ||
487f05e1 AS |
2702 | /* |
2703 | * We want to maintain the following priority of scheduling: | |
2704 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2705 | * - task pinned (EVENT_PINNED) | |
2706 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2707 | * - task flexible (EVENT_FLEXIBLE). | |
2708 | * | |
2709 | * In order to avoid unscheduling and scheduling back in everything every | |
2710 | * time an event is added, only do it for the groups of equal priority and | |
2711 | * below. | |
2712 | * | |
2713 | * This can be called after a batch operation on task events, in which case | |
2714 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2715 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2716 | */ | |
3e349507 | 2717 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2718 | struct perf_event_context *task_ctx, |
2719 | enum event_type_t event_type) | |
0017960f | 2720 | { |
bd903afe | 2721 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2722 | bool cpu_event = !!(event_type & EVENT_CPU); |
2723 | ||
2724 | /* | |
2725 | * If pinned groups are involved, flexible groups also need to be | |
2726 | * scheduled out. | |
2727 | */ | |
2728 | if (event_type & EVENT_PINNED) | |
2729 | event_type |= EVENT_FLEXIBLE; | |
2730 | ||
bd903afe SL |
2731 | ctx_event_type = event_type & EVENT_ALL; |
2732 | ||
3e349507 PZ |
2733 | perf_pmu_disable(cpuctx->ctx.pmu); |
2734 | if (task_ctx) | |
487f05e1 AS |
2735 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2736 | ||
2737 | /* | |
2738 | * Decide which cpu ctx groups to schedule out based on the types | |
2739 | * of events that caused rescheduling: | |
2740 | * - EVENT_CPU: schedule out corresponding groups; | |
2741 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2742 | * - otherwise, do nothing more. | |
2743 | */ | |
2744 | if (cpu_event) | |
2745 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2746 | else if (ctx_event_type & EVENT_PINNED) | |
2747 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2748 | ||
3e349507 PZ |
2749 | perf_event_sched_in(cpuctx, task_ctx, current); |
2750 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2751 | } |
2752 | ||
c68d224e SE |
2753 | void perf_pmu_resched(struct pmu *pmu) |
2754 | { | |
2755 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2756 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2757 | ||
2758 | perf_ctx_lock(cpuctx, task_ctx); | |
2759 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2760 | perf_ctx_unlock(cpuctx, task_ctx); | |
2761 | } | |
2762 | ||
0793a61d | 2763 | /* |
cdd6c482 | 2764 | * Cross CPU call to install and enable a performance event |
682076ae | 2765 | * |
a096309b PZ |
2766 | * Very similar to remote_function() + event_function() but cannot assume that |
2767 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2768 | */ |
fe4b04fa | 2769 | static int __perf_install_in_context(void *info) |
0793a61d | 2770 | { |
a096309b PZ |
2771 | struct perf_event *event = info; |
2772 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2773 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2774 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2775 | bool reprogram = true; |
a096309b | 2776 | int ret = 0; |
0793a61d | 2777 | |
63b6da39 | 2778 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2779 | if (ctx->task) { |
b58f6b0d PZ |
2780 | raw_spin_lock(&ctx->lock); |
2781 | task_ctx = ctx; | |
a096309b | 2782 | |
63cae12b | 2783 | reprogram = (ctx->task == current); |
b58f6b0d | 2784 | |
39a43640 | 2785 | /* |
63cae12b PZ |
2786 | * If the task is running, it must be running on this CPU, |
2787 | * otherwise we cannot reprogram things. | |
2788 | * | |
2789 | * If its not running, we don't care, ctx->lock will | |
2790 | * serialize against it becoming runnable. | |
39a43640 | 2791 | */ |
63cae12b PZ |
2792 | if (task_curr(ctx->task) && !reprogram) { |
2793 | ret = -ESRCH; | |
2794 | goto unlock; | |
2795 | } | |
a096309b | 2796 | |
63cae12b | 2797 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2798 | } else if (task_ctx) { |
2799 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2800 | } |
b58f6b0d | 2801 | |
33801b94 | 2802 | #ifdef CONFIG_CGROUP_PERF |
33238c50 | 2803 | if (event->state > PERF_EVENT_STATE_OFF && is_cgroup_event(event)) { |
33801b94 | 2804 | /* |
2805 | * If the current cgroup doesn't match the event's | |
2806 | * cgroup, we should not try to schedule it. | |
2807 | */ | |
2808 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2809 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2810 | event->cgrp->css.cgroup); | |
2811 | } | |
2812 | #endif | |
2813 | ||
63cae12b | 2814 | if (reprogram) { |
a096309b PZ |
2815 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2816 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2817 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2818 | } else { |
2819 | add_event_to_ctx(event, ctx); | |
2820 | } | |
2821 | ||
63b6da39 | 2822 | unlock: |
2c29ef0f | 2823 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2824 | |
a096309b | 2825 | return ret; |
0793a61d TG |
2826 | } |
2827 | ||
8a58ddae AS |
2828 | static bool exclusive_event_installable(struct perf_event *event, |
2829 | struct perf_event_context *ctx); | |
2830 | ||
0793a61d | 2831 | /* |
a096309b PZ |
2832 | * Attach a performance event to a context. |
2833 | * | |
2834 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2835 | */ |
2836 | static void | |
cdd6c482 IM |
2837 | perf_install_in_context(struct perf_event_context *ctx, |
2838 | struct perf_event *event, | |
0793a61d TG |
2839 | int cpu) |
2840 | { | |
a096309b | 2841 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2842 | |
fe4b04fa PZ |
2843 | lockdep_assert_held(&ctx->mutex); |
2844 | ||
8a58ddae AS |
2845 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2846 | ||
0cda4c02 YZ |
2847 | if (event->cpu != -1) |
2848 | event->cpu = cpu; | |
c3f00c70 | 2849 | |
0b8f1e2e PZ |
2850 | /* |
2851 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2852 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2853 | */ | |
2854 | smp_store_release(&event->ctx, ctx); | |
2855 | ||
db0503e4 PZ |
2856 | /* |
2857 | * perf_event_attr::disabled events will not run and can be initialized | |
2858 | * without IPI. Except when this is the first event for the context, in | |
2859 | * that case we need the magic of the IPI to set ctx->is_active. | |
2860 | * | |
2861 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2862 | * event will issue the IPI and reprogram the hardware. | |
2863 | */ | |
2864 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2865 | raw_spin_lock_irq(&ctx->lock); | |
2866 | if (ctx->task == TASK_TOMBSTONE) { | |
2867 | raw_spin_unlock_irq(&ctx->lock); | |
2868 | return; | |
2869 | } | |
2870 | add_event_to_ctx(event, ctx); | |
2871 | raw_spin_unlock_irq(&ctx->lock); | |
2872 | return; | |
2873 | } | |
2874 | ||
a096309b PZ |
2875 | if (!task) { |
2876 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2877 | return; | |
2878 | } | |
2879 | ||
2880 | /* | |
2881 | * Should not happen, we validate the ctx is still alive before calling. | |
2882 | */ | |
2883 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2884 | return; | |
2885 | ||
39a43640 PZ |
2886 | /* |
2887 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2888 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2889 | * |
2890 | * Instead we use task_curr(), which tells us if the task is running. | |
2891 | * However, since we use task_curr() outside of rq::lock, we can race | |
2892 | * against the actual state. This means the result can be wrong. | |
2893 | * | |
2894 | * If we get a false positive, we retry, this is harmless. | |
2895 | * | |
2896 | * If we get a false negative, things are complicated. If we are after | |
2897 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2898 | * value must be correct. If we're before, it doesn't matter since | |
2899 | * perf_event_context_sched_in() will program the counter. | |
2900 | * | |
2901 | * However, this hinges on the remote context switch having observed | |
2902 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2903 | * ctx::lock in perf_event_context_sched_in(). | |
2904 | * | |
2905 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2906 | * we know any future context switch of task must see the | |
2907 | * perf_event_ctpx[] store. | |
39a43640 | 2908 | */ |
63cae12b | 2909 | |
63b6da39 | 2910 | /* |
63cae12b PZ |
2911 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2912 | * task_cpu() load, such that if the IPI then does not find the task | |
2913 | * running, a future context switch of that task must observe the | |
2914 | * store. | |
63b6da39 | 2915 | */ |
63cae12b PZ |
2916 | smp_mb(); |
2917 | again: | |
2918 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2919 | return; |
2920 | ||
2921 | raw_spin_lock_irq(&ctx->lock); | |
2922 | task = ctx->task; | |
84c4e620 | 2923 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2924 | /* |
2925 | * Cannot happen because we already checked above (which also | |
2926 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2927 | * against perf_event_exit_task_context(). | |
2928 | */ | |
63b6da39 PZ |
2929 | raw_spin_unlock_irq(&ctx->lock); |
2930 | return; | |
2931 | } | |
39a43640 | 2932 | /* |
63cae12b PZ |
2933 | * If the task is not running, ctx->lock will avoid it becoming so, |
2934 | * thus we can safely install the event. | |
39a43640 | 2935 | */ |
63cae12b PZ |
2936 | if (task_curr(task)) { |
2937 | raw_spin_unlock_irq(&ctx->lock); | |
2938 | goto again; | |
2939 | } | |
2940 | add_event_to_ctx(event, ctx); | |
2941 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2942 | } |
2943 | ||
d859e29f | 2944 | /* |
cdd6c482 | 2945 | * Cross CPU call to enable a performance event |
d859e29f | 2946 | */ |
fae3fde6 PZ |
2947 | static void __perf_event_enable(struct perf_event *event, |
2948 | struct perf_cpu_context *cpuctx, | |
2949 | struct perf_event_context *ctx, | |
2950 | void *info) | |
04289bb9 | 2951 | { |
cdd6c482 | 2952 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2953 | struct perf_event_context *task_ctx; |
04289bb9 | 2954 | |
6e801e01 PZ |
2955 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2956 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2957 | return; |
3cbed429 | 2958 | |
bd2afa49 PZ |
2959 | if (ctx->is_active) |
2960 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2961 | ||
0d3d73aa | 2962 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
33238c50 | 2963 | perf_cgroup_event_enable(event, ctx); |
04289bb9 | 2964 | |
fae3fde6 PZ |
2965 | if (!ctx->is_active) |
2966 | return; | |
2967 | ||
e5d1367f | 2968 | if (!event_filter_match(event)) { |
bd2afa49 | 2969 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2970 | return; |
e5d1367f | 2971 | } |
f4c4176f | 2972 | |
04289bb9 | 2973 | /* |
cdd6c482 | 2974 | * If the event is in a group and isn't the group leader, |
d859e29f | 2975 | * then don't put it on unless the group is on. |
04289bb9 | 2976 | */ |
bd2afa49 PZ |
2977 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2978 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2979 | return; |
bd2afa49 | 2980 | } |
fe4b04fa | 2981 | |
fae3fde6 PZ |
2982 | task_ctx = cpuctx->task_ctx; |
2983 | if (ctx->task) | |
2984 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2985 | |
487f05e1 | 2986 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2987 | } |
2988 | ||
d859e29f | 2989 | /* |
788faab7 | 2990 | * Enable an event. |
c93f7669 | 2991 | * |
cdd6c482 IM |
2992 | * If event->ctx is a cloned context, callers must make sure that |
2993 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2994 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2995 | * perf_event_for_each_child or perf_event_for_each as described |
2996 | * for perf_event_disable. | |
d859e29f | 2997 | */ |
f63a8daa | 2998 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2999 | { |
cdd6c482 | 3000 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 3001 | |
7b648018 | 3002 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
3003 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
3004 | event->state < PERF_EVENT_STATE_ERROR) { | |
9f0c4fa1 | 3005 | out: |
7b648018 | 3006 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
3007 | return; |
3008 | } | |
3009 | ||
d859e29f | 3010 | /* |
cdd6c482 | 3011 | * If the event is in error state, clear that first. |
7b648018 PZ |
3012 | * |
3013 | * That way, if we see the event in error state below, we know that it | |
3014 | * has gone back into error state, as distinct from the task having | |
3015 | * been scheduled away before the cross-call arrived. | |
d859e29f | 3016 | */ |
9f0c4fa1 KL |
3017 | if (event->state == PERF_EVENT_STATE_ERROR) { |
3018 | /* | |
3019 | * Detached SIBLING events cannot leave ERROR state. | |
3020 | */ | |
3021 | if (event->event_caps & PERF_EV_CAP_SIBLING && | |
3022 | event->group_leader == event) | |
3023 | goto out; | |
3024 | ||
cdd6c482 | 3025 | event->state = PERF_EVENT_STATE_OFF; |
9f0c4fa1 | 3026 | } |
e625cce1 | 3027 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 3028 | |
fae3fde6 | 3029 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 3030 | } |
f63a8daa PZ |
3031 | |
3032 | /* | |
3033 | * See perf_event_disable(); | |
3034 | */ | |
3035 | void perf_event_enable(struct perf_event *event) | |
3036 | { | |
3037 | struct perf_event_context *ctx; | |
3038 | ||
3039 | ctx = perf_event_ctx_lock(event); | |
3040 | _perf_event_enable(event); | |
3041 | perf_event_ctx_unlock(event, ctx); | |
3042 | } | |
dcfce4a0 | 3043 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 3044 | |
375637bc AS |
3045 | struct stop_event_data { |
3046 | struct perf_event *event; | |
3047 | unsigned int restart; | |
3048 | }; | |
3049 | ||
95ff4ca2 AS |
3050 | static int __perf_event_stop(void *info) |
3051 | { | |
375637bc AS |
3052 | struct stop_event_data *sd = info; |
3053 | struct perf_event *event = sd->event; | |
95ff4ca2 | 3054 | |
375637bc | 3055 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
3056 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
3057 | return 0; | |
3058 | ||
3059 | /* matches smp_wmb() in event_sched_in() */ | |
3060 | smp_rmb(); | |
3061 | ||
3062 | /* | |
3063 | * There is a window with interrupts enabled before we get here, | |
3064 | * so we need to check again lest we try to stop another CPU's event. | |
3065 | */ | |
3066 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3067 | return -EAGAIN; | |
3068 | ||
3069 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3070 | ||
375637bc AS |
3071 | /* |
3072 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3073 | * but it is only used for events with AUX ring buffer, and such | |
3074 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3075 | * see comments in perf_aux_output_begin(). | |
3076 | * | |
788faab7 | 3077 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3078 | * while restarting. |
3079 | */ | |
3080 | if (sd->restart) | |
c9bbdd48 | 3081 | event->pmu->start(event, 0); |
375637bc | 3082 | |
95ff4ca2 AS |
3083 | return 0; |
3084 | } | |
3085 | ||
767ae086 | 3086 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3087 | { |
3088 | struct stop_event_data sd = { | |
3089 | .event = event, | |
767ae086 | 3090 | .restart = restart, |
375637bc AS |
3091 | }; |
3092 | int ret = 0; | |
3093 | ||
3094 | do { | |
3095 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3096 | return 0; | |
3097 | ||
3098 | /* matches smp_wmb() in event_sched_in() */ | |
3099 | smp_rmb(); | |
3100 | ||
3101 | /* | |
3102 | * We only want to restart ACTIVE events, so if the event goes | |
3103 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3104 | * fall through with ret==-ENXIO. | |
3105 | */ | |
3106 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3107 | __perf_event_stop, &sd); | |
3108 | } while (ret == -EAGAIN); | |
3109 | ||
3110 | return ret; | |
3111 | } | |
3112 | ||
3113 | /* | |
3114 | * In order to contain the amount of racy and tricky in the address filter | |
3115 | * configuration management, it is a two part process: | |
3116 | * | |
3117 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3118 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3119 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3120 | * (p2) when an event is scheduled in (pmu::add), it calls |
3121 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3122 | * if the generation has changed since the previous call. | |
3123 | * | |
3124 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3125 | * | |
3126 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3127 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3128 | * ioctl; | |
3129 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
c1e8d7c6 | 3130 | * registered mapping, called for every new mmap(), with mm::mmap_lock down |
375637bc AS |
3131 | * for reading; |
3132 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3133 | * of exec. | |
3134 | */ | |
3135 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3136 | { | |
3137 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3138 | ||
3139 | if (!has_addr_filter(event)) | |
3140 | return; | |
3141 | ||
3142 | raw_spin_lock(&ifh->lock); | |
3143 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3144 | event->pmu->addr_filters_sync(event); | |
3145 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3146 | } | |
3147 | raw_spin_unlock(&ifh->lock); | |
3148 | } | |
3149 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3150 | ||
f63a8daa | 3151 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3152 | { |
2023b359 | 3153 | /* |
cdd6c482 | 3154 | * not supported on inherited events |
2023b359 | 3155 | */ |
2e939d1d | 3156 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3157 | return -EINVAL; |
3158 | ||
cdd6c482 | 3159 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3160 | _perf_event_enable(event); |
2023b359 PZ |
3161 | |
3162 | return 0; | |
79f14641 | 3163 | } |
f63a8daa PZ |
3164 | |
3165 | /* | |
3166 | * See perf_event_disable() | |
3167 | */ | |
3168 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3169 | { | |
3170 | struct perf_event_context *ctx; | |
3171 | int ret; | |
3172 | ||
3173 | ctx = perf_event_ctx_lock(event); | |
3174 | ret = _perf_event_refresh(event, refresh); | |
3175 | perf_event_ctx_unlock(event, ctx); | |
3176 | ||
3177 | return ret; | |
3178 | } | |
26ca5c11 | 3179 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3180 | |
32ff77e8 MC |
3181 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3182 | struct perf_event_attr *attr) | |
3183 | { | |
3184 | int err; | |
3185 | ||
3186 | _perf_event_disable(bp); | |
3187 | ||
3188 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3189 | |
bf06278c | 3190 | if (!bp->attr.disabled) |
32ff77e8 | 3191 | _perf_event_enable(bp); |
bf06278c JO |
3192 | |
3193 | return err; | |
32ff77e8 MC |
3194 | } |
3195 | ||
3196 | static int perf_event_modify_attr(struct perf_event *event, | |
3197 | struct perf_event_attr *attr) | |
3198 | { | |
47f661ec ME |
3199 | int (*func)(struct perf_event *, struct perf_event_attr *); |
3200 | struct perf_event *child; | |
3201 | int err; | |
3202 | ||
32ff77e8 MC |
3203 | if (event->attr.type != attr->type) |
3204 | return -EINVAL; | |
3205 | ||
3206 | switch (event->attr.type) { | |
3207 | case PERF_TYPE_BREAKPOINT: | |
47f661ec ME |
3208 | func = perf_event_modify_breakpoint; |
3209 | break; | |
32ff77e8 MC |
3210 | default: |
3211 | /* Place holder for future additions. */ | |
3212 | return -EOPNOTSUPP; | |
3213 | } | |
47f661ec ME |
3214 | |
3215 | WARN_ON_ONCE(event->ctx->parent_ctx); | |
3216 | ||
3217 | mutex_lock(&event->child_mutex); | |
3218 | err = func(event, attr); | |
3219 | if (err) | |
3220 | goto out; | |
3221 | list_for_each_entry(child, &event->child_list, child_list) { | |
3222 | err = func(child, attr); | |
3223 | if (err) | |
3224 | goto out; | |
3225 | } | |
3226 | out: | |
3227 | mutex_unlock(&event->child_mutex); | |
3228 | return err; | |
32ff77e8 MC |
3229 | } |
3230 | ||
5b0311e1 FW |
3231 | static void ctx_sched_out(struct perf_event_context *ctx, |
3232 | struct perf_cpu_context *cpuctx, | |
3233 | enum event_type_t event_type) | |
235c7fc7 | 3234 | { |
6668128a | 3235 | struct perf_event *event, *tmp; |
db24d33e | 3236 | int is_active = ctx->is_active; |
235c7fc7 | 3237 | |
c994d613 | 3238 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3239 | |
39a43640 PZ |
3240 | if (likely(!ctx->nr_events)) { |
3241 | /* | |
3242 | * See __perf_remove_from_context(). | |
3243 | */ | |
3244 | WARN_ON_ONCE(ctx->is_active); | |
3245 | if (ctx->task) | |
3246 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3247 | return; |
39a43640 PZ |
3248 | } |
3249 | ||
db24d33e | 3250 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3251 | if (!(ctx->is_active & EVENT_ALL)) |
3252 | ctx->is_active = 0; | |
3253 | ||
63e30d3e PZ |
3254 | if (ctx->task) { |
3255 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3256 | if (!ctx->is_active) | |
3257 | cpuctx->task_ctx = NULL; | |
3258 | } | |
facc4307 | 3259 | |
8fdc6539 PZ |
3260 | /* |
3261 | * Always update time if it was set; not only when it changes. | |
3262 | * Otherwise we can 'forget' to update time for any but the last | |
3263 | * context we sched out. For example: | |
3264 | * | |
3265 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3266 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3267 | * | |
3268 | * would only update time for the pinned events. | |
3269 | */ | |
3cbaa590 PZ |
3270 | if (is_active & EVENT_TIME) { |
3271 | /* update (and stop) ctx time */ | |
3272 | update_context_time(ctx); | |
3273 | update_cgrp_time_from_cpuctx(cpuctx); | |
3274 | } | |
3275 | ||
8fdc6539 PZ |
3276 | is_active ^= ctx->is_active; /* changed bits */ |
3277 | ||
3cbaa590 | 3278 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3279 | return; |
5b0311e1 | 3280 | |
075e0b00 | 3281 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3282 | if (is_active & EVENT_PINNED) { |
6668128a | 3283 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3284 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3285 | } |
889ff015 | 3286 | |
3cbaa590 | 3287 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3288 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3289 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3290 | |
3291 | /* | |
3292 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3293 | * rotate_necessary, is will be reset by | |
3294 | * ctx_flexible_sched_in() when needed. | |
3295 | */ | |
3296 | ctx->rotate_necessary = 0; | |
9ed6060d | 3297 | } |
1b9a644f | 3298 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3299 | } |
3300 | ||
564c2b21 | 3301 | /* |
5a3126d4 PZ |
3302 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3303 | * cloned from the same version of the same context. | |
3304 | * | |
3305 | * Equivalence is measured using a generation number in the context that is | |
3306 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3307 | * and list_del_event(). | |
564c2b21 | 3308 | */ |
cdd6c482 IM |
3309 | static int context_equiv(struct perf_event_context *ctx1, |
3310 | struct perf_event_context *ctx2) | |
564c2b21 | 3311 | { |
211de6eb PZ |
3312 | lockdep_assert_held(&ctx1->lock); |
3313 | lockdep_assert_held(&ctx2->lock); | |
3314 | ||
5a3126d4 PZ |
3315 | /* Pinning disables the swap optimization */ |
3316 | if (ctx1->pin_count || ctx2->pin_count) | |
3317 | return 0; | |
3318 | ||
3319 | /* If ctx1 is the parent of ctx2 */ | |
3320 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3321 | return 1; | |
3322 | ||
3323 | /* If ctx2 is the parent of ctx1 */ | |
3324 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3325 | return 1; | |
3326 | ||
3327 | /* | |
3328 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3329 | * hierarchy, see perf_event_init_context(). | |
3330 | */ | |
3331 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3332 | ctx1->parent_gen == ctx2->parent_gen) | |
3333 | return 1; | |
3334 | ||
3335 | /* Unmatched */ | |
3336 | return 0; | |
564c2b21 PM |
3337 | } |
3338 | ||
cdd6c482 IM |
3339 | static void __perf_event_sync_stat(struct perf_event *event, |
3340 | struct perf_event *next_event) | |
bfbd3381 PZ |
3341 | { |
3342 | u64 value; | |
3343 | ||
cdd6c482 | 3344 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3345 | return; |
3346 | ||
3347 | /* | |
cdd6c482 | 3348 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3349 | * because we're in the middle of a context switch and have IRQs |
3350 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3351 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3352 | * don't need to use it. |
3353 | */ | |
0d3d73aa | 3354 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3355 | event->pmu->read(event); |
bfbd3381 | 3356 | |
0d3d73aa | 3357 | perf_event_update_time(event); |
bfbd3381 PZ |
3358 | |
3359 | /* | |
cdd6c482 | 3360 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3361 | * values when we flip the contexts. |
3362 | */ | |
e7850595 PZ |
3363 | value = local64_read(&next_event->count); |
3364 | value = local64_xchg(&event->count, value); | |
3365 | local64_set(&next_event->count, value); | |
bfbd3381 | 3366 | |
cdd6c482 IM |
3367 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3368 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3369 | |
bfbd3381 | 3370 | /* |
19d2e755 | 3371 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3372 | */ |
cdd6c482 IM |
3373 | perf_event_update_userpage(event); |
3374 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3375 | } |
3376 | ||
cdd6c482 IM |
3377 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3378 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3379 | { |
cdd6c482 | 3380 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3381 | |
3382 | if (!ctx->nr_stat) | |
3383 | return; | |
3384 | ||
02ffdbc8 PZ |
3385 | update_context_time(ctx); |
3386 | ||
cdd6c482 IM |
3387 | event = list_first_entry(&ctx->event_list, |
3388 | struct perf_event, event_entry); | |
bfbd3381 | 3389 | |
cdd6c482 IM |
3390 | next_event = list_first_entry(&next_ctx->event_list, |
3391 | struct perf_event, event_entry); | |
bfbd3381 | 3392 | |
cdd6c482 IM |
3393 | while (&event->event_entry != &ctx->event_list && |
3394 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3395 | |
cdd6c482 | 3396 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3397 | |
cdd6c482 IM |
3398 | event = list_next_entry(event, event_entry); |
3399 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3400 | } |
3401 | } | |
3402 | ||
fe4b04fa PZ |
3403 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3404 | struct task_struct *next) | |
0793a61d | 3405 | { |
8dc85d54 | 3406 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3407 | struct perf_event_context *next_ctx; |
5a3126d4 | 3408 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3409 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3410 | int do_switch = 1; |
44fae179 | 3411 | struct pmu *pmu; |
0793a61d | 3412 | |
108b02cf PZ |
3413 | if (likely(!ctx)) |
3414 | return; | |
10989fb2 | 3415 | |
44fae179 | 3416 | pmu = ctx->pmu; |
108b02cf PZ |
3417 | cpuctx = __get_cpu_context(ctx); |
3418 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3419 | return; |
3420 | ||
c93f7669 | 3421 | rcu_read_lock(); |
8dc85d54 | 3422 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3423 | if (!next_ctx) |
3424 | goto unlock; | |
3425 | ||
3426 | parent = rcu_dereference(ctx->parent_ctx); | |
3427 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3428 | ||
3429 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3430 | if (!parent && !next_parent) |
5a3126d4 PZ |
3431 | goto unlock; |
3432 | ||
3433 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3434 | /* |
3435 | * Looks like the two contexts are clones, so we might be | |
3436 | * able to optimize the context switch. We lock both | |
3437 | * contexts and check that they are clones under the | |
3438 | * lock (including re-checking that neither has been | |
3439 | * uncloned in the meantime). It doesn't matter which | |
3440 | * order we take the locks because no other cpu could | |
3441 | * be trying to lock both of these tasks. | |
3442 | */ | |
e625cce1 TG |
3443 | raw_spin_lock(&ctx->lock); |
3444 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3445 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 | 3446 | |
63b6da39 PZ |
3447 | WRITE_ONCE(ctx->task, next); |
3448 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3449 | |
44fae179 KL |
3450 | perf_pmu_disable(pmu); |
3451 | ||
3452 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3453 | pmu->sched_task(ctx, false); | |
3454 | ||
c2b98a86 AB |
3455 | /* |
3456 | * PMU specific parts of task perf context can require | |
3457 | * additional synchronization. As an example of such | |
3458 | * synchronization see implementation details of Intel | |
3459 | * LBR call stack data profiling; | |
3460 | */ | |
3461 | if (pmu->swap_task_ctx) | |
3462 | pmu->swap_task_ctx(ctx, next_ctx); | |
3463 | else | |
3464 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3465 | |
44fae179 KL |
3466 | perf_pmu_enable(pmu); |
3467 | ||
63b6da39 PZ |
3468 | /* |
3469 | * RCU_INIT_POINTER here is safe because we've not | |
3470 | * modified the ctx and the above modification of | |
3471 | * ctx->task and ctx->task_ctx_data are immaterial | |
3472 | * since those values are always verified under | |
3473 | * ctx->lock which we're now holding. | |
3474 | */ | |
3475 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3476 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3477 | ||
c93f7669 | 3478 | do_switch = 0; |
bfbd3381 | 3479 | |
cdd6c482 | 3480 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3481 | } |
e625cce1 TG |
3482 | raw_spin_unlock(&next_ctx->lock); |
3483 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3484 | } |
5a3126d4 | 3485 | unlock: |
c93f7669 | 3486 | rcu_read_unlock(); |
564c2b21 | 3487 | |
c93f7669 | 3488 | if (do_switch) { |
facc4307 | 3489 | raw_spin_lock(&ctx->lock); |
44fae179 KL |
3490 | perf_pmu_disable(pmu); |
3491 | ||
3492 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3493 | pmu->sched_task(ctx, false); | |
487f05e1 | 3494 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
44fae179 KL |
3495 | |
3496 | perf_pmu_enable(pmu); | |
facc4307 | 3497 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3498 | } |
0793a61d TG |
3499 | } |
3500 | ||
a5398bff KL |
3501 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3502 | ||
ba532500 YZ |
3503 | void perf_sched_cb_dec(struct pmu *pmu) |
3504 | { | |
e48c1788 PZ |
3505 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3506 | ||
a5398bff KL |
3507 | this_cpu_dec(perf_sched_cb_usages); |
3508 | ||
3509 | if (!--cpuctx->sched_cb_usage) | |
3510 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3511 | } |
3512 | ||
e48c1788 | 3513 | |
ba532500 YZ |
3514 | void perf_sched_cb_inc(struct pmu *pmu) |
3515 | { | |
e48c1788 PZ |
3516 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3517 | ||
a5398bff KL |
3518 | if (!cpuctx->sched_cb_usage++) |
3519 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3520 | ||
3521 | this_cpu_inc(perf_sched_cb_usages); | |
ba532500 YZ |
3522 | } |
3523 | ||
3524 | /* | |
3525 | * This function provides the context switch callback to the lower code | |
3526 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3527 | * |
3528 | * This callback is relevant even to per-cpu events; for example multi event | |
3529 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3530 | * all queued PEBS records before we context switch to a new task. | |
ba532500 | 3531 | */ |
556cccad KL |
3532 | static void __perf_pmu_sched_task(struct perf_cpu_context *cpuctx, bool sched_in) |
3533 | { | |
3534 | struct pmu *pmu; | |
3535 | ||
3536 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ | |
3537 | ||
3538 | if (WARN_ON_ONCE(!pmu->sched_task)) | |
3539 | return; | |
3540 | ||
3541 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
3542 | perf_pmu_disable(pmu); | |
3543 | ||
3544 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
3545 | ||
3546 | perf_pmu_enable(pmu); | |
3547 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
3548 | } | |
3549 | ||
a5398bff KL |
3550 | static void perf_pmu_sched_task(struct task_struct *prev, |
3551 | struct task_struct *next, | |
3552 | bool sched_in) | |
3553 | { | |
3554 | struct perf_cpu_context *cpuctx; | |
3555 | ||
3556 | if (prev == next) | |
3557 | return; | |
3558 | ||
3559 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { | |
3560 | /* will be handled in perf_event_context_sched_in/out */ | |
3561 | if (cpuctx->task_ctx) | |
3562 | continue; | |
3563 | ||
3564 | __perf_pmu_sched_task(cpuctx, sched_in); | |
3565 | } | |
3566 | } | |
3567 | ||
45ac1403 AH |
3568 | static void perf_event_switch(struct task_struct *task, |
3569 | struct task_struct *next_prev, bool sched_in); | |
3570 | ||
8dc85d54 PZ |
3571 | #define for_each_task_context_nr(ctxn) \ |
3572 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3573 | ||
3574 | /* | |
3575 | * Called from scheduler to remove the events of the current task, | |
3576 | * with interrupts disabled. | |
3577 | * | |
3578 | * We stop each event and update the event value in event->count. | |
3579 | * | |
3580 | * This does not protect us against NMI, but disable() | |
3581 | * sets the disabled bit in the control field of event _before_ | |
3582 | * accessing the event control register. If a NMI hits, then it will | |
3583 | * not restart the event. | |
3584 | */ | |
ab0cce56 JO |
3585 | void __perf_event_task_sched_out(struct task_struct *task, |
3586 | struct task_struct *next) | |
8dc85d54 PZ |
3587 | { |
3588 | int ctxn; | |
3589 | ||
a5398bff KL |
3590 | if (__this_cpu_read(perf_sched_cb_usages)) |
3591 | perf_pmu_sched_task(task, next, false); | |
3592 | ||
45ac1403 AH |
3593 | if (atomic_read(&nr_switch_events)) |
3594 | perf_event_switch(task, next, false); | |
3595 | ||
8dc85d54 PZ |
3596 | for_each_task_context_nr(ctxn) |
3597 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3598 | |
3599 | /* | |
3600 | * if cgroup events exist on this CPU, then we need | |
3601 | * to check if we have to switch out PMU state. | |
3602 | * cgroup event are system-wide mode only | |
3603 | */ | |
4a32fea9 | 3604 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3605 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3606 | } |
3607 | ||
5b0311e1 FW |
3608 | /* |
3609 | * Called with IRQs disabled | |
3610 | */ | |
3611 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3612 | enum event_type_t event_type) | |
3613 | { | |
3614 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3615 | } |
3616 | ||
6eef8a71 | 3617 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3618 | { |
24fb6b8e IR |
3619 | const struct perf_event *le = *(const struct perf_event **)l; |
3620 | const struct perf_event *re = *(const struct perf_event **)r; | |
6eef8a71 IR |
3621 | |
3622 | return le->group_index < re->group_index; | |
3623 | } | |
3624 | ||
3625 | static void swap_ptr(void *l, void *r) | |
3626 | { | |
3627 | void **lp = l, **rp = r; | |
3628 | ||
3629 | swap(*lp, *rp); | |
3630 | } | |
3631 | ||
3632 | static const struct min_heap_callbacks perf_min_heap = { | |
3633 | .elem_size = sizeof(struct perf_event *), | |
3634 | .less = perf_less_group_idx, | |
3635 | .swp = swap_ptr, | |
3636 | }; | |
3637 | ||
3638 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3639 | { | |
3640 | struct perf_event **itrs = heap->data; | |
3641 | ||
3642 | if (event) { | |
3643 | itrs[heap->nr] = event; | |
3644 | heap->nr++; | |
3645 | } | |
3646 | } | |
3647 | ||
836196be IR |
3648 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3649 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3650 | int (*func)(struct perf_event *, void *), |
3651 | void *data) | |
3652 | { | |
95ed6c70 IR |
3653 | #ifdef CONFIG_CGROUP_PERF |
3654 | struct cgroup_subsys_state *css = NULL; | |
3655 | #endif | |
6eef8a71 IR |
3656 | /* Space for per CPU and/or any CPU event iterators. */ |
3657 | struct perf_event *itrs[2]; | |
836196be IR |
3658 | struct min_heap event_heap; |
3659 | struct perf_event **evt; | |
1cac7b1a | 3660 | int ret; |
8e1a2031 | 3661 | |
836196be IR |
3662 | if (cpuctx) { |
3663 | event_heap = (struct min_heap){ | |
3664 | .data = cpuctx->heap, | |
3665 | .nr = 0, | |
3666 | .size = cpuctx->heap_size, | |
3667 | }; | |
c2283c93 IR |
3668 | |
3669 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3670 | |
3671 | #ifdef CONFIG_CGROUP_PERF | |
3672 | if (cpuctx->cgrp) | |
3673 | css = &cpuctx->cgrp->css; | |
3674 | #endif | |
836196be IR |
3675 | } else { |
3676 | event_heap = (struct min_heap){ | |
3677 | .data = itrs, | |
3678 | .nr = 0, | |
3679 | .size = ARRAY_SIZE(itrs), | |
3680 | }; | |
3681 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3682 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3683 | } |
3684 | evt = event_heap.data; | |
3685 | ||
95ed6c70 IR |
3686 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3687 | ||
3688 | #ifdef CONFIG_CGROUP_PERF | |
3689 | for (; css; css = css->parent) | |
3690 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3691 | #endif | |
1cac7b1a | 3692 | |
6eef8a71 | 3693 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3694 | |
6eef8a71 | 3695 | while (event_heap.nr) { |
1cac7b1a PZ |
3696 | ret = func(*evt, data); |
3697 | if (ret) | |
3698 | return ret; | |
3699 | ||
3700 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3701 | if (*evt) |
3702 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3703 | else | |
3704 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3705 | } |
0793a61d | 3706 | |
1cac7b1a PZ |
3707 | return 0; |
3708 | } | |
3709 | ||
f7925653 SL |
3710 | static inline bool event_update_userpage(struct perf_event *event) |
3711 | { | |
3712 | if (likely(!atomic_read(&event->mmap_count))) | |
3713 | return false; | |
3714 | ||
3715 | perf_event_update_time(event); | |
3716 | perf_set_shadow_time(event, event->ctx); | |
3717 | perf_event_update_userpage(event); | |
3718 | ||
3719 | return true; | |
3720 | } | |
3721 | ||
3722 | static inline void group_update_userpage(struct perf_event *group_event) | |
3723 | { | |
3724 | struct perf_event *event; | |
3725 | ||
3726 | if (!event_update_userpage(group_event)) | |
3727 | return; | |
3728 | ||
3729 | for_each_sibling_event(event, group_event) | |
3730 | event_update_userpage(event); | |
3731 | } | |
3732 | ||
ab6f824c | 3733 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3734 | { |
2c2366c7 PZ |
3735 | struct perf_event_context *ctx = event->ctx; |
3736 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3737 | int *can_add_hw = data; | |
ab6f824c | 3738 | |
1cac7b1a PZ |
3739 | if (event->state <= PERF_EVENT_STATE_OFF) |
3740 | return 0; | |
3741 | ||
3742 | if (!event_filter_match(event)) | |
3743 | return 0; | |
3744 | ||
2c2366c7 PZ |
3745 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3746 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3747 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3748 | } |
1cac7b1a | 3749 | |
ab6f824c | 3750 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
f7925653 | 3751 | *can_add_hw = 0; |
33238c50 PZ |
3752 | if (event->attr.pinned) { |
3753 | perf_cgroup_event_disable(event, ctx); | |
ab6f824c | 3754 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); |
f7925653 SL |
3755 | } else { |
3756 | ctx->rotate_necessary = 1; | |
3757 | perf_mux_hrtimer_restart(cpuctx); | |
3758 | group_update_userpage(event); | |
33238c50 | 3759 | } |
3b6f9e5c | 3760 | } |
1cac7b1a PZ |
3761 | |
3762 | return 0; | |
5b0311e1 FW |
3763 | } |
3764 | ||
3765 | static void | |
1cac7b1a PZ |
3766 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3767 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3768 | { |
2c2366c7 | 3769 | int can_add_hw = 1; |
3b6f9e5c | 3770 | |
836196be IR |
3771 | if (ctx != &cpuctx->ctx) |
3772 | cpuctx = NULL; | |
3773 | ||
3774 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3775 | smp_processor_id(), |
2c2366c7 | 3776 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3777 | } |
8e1a2031 | 3778 | |
1cac7b1a PZ |
3779 | static void |
3780 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3781 | struct perf_cpu_context *cpuctx) | |
3782 | { | |
2c2366c7 | 3783 | int can_add_hw = 1; |
0793a61d | 3784 | |
836196be IR |
3785 | if (ctx != &cpuctx->ctx) |
3786 | cpuctx = NULL; | |
3787 | ||
3788 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3789 | smp_processor_id(), |
2c2366c7 | 3790 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3791 | } |
3792 | ||
3793 | static void | |
3794 | ctx_sched_in(struct perf_event_context *ctx, | |
3795 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3796 | enum event_type_t event_type, |
3797 | struct task_struct *task) | |
5b0311e1 | 3798 | { |
db24d33e | 3799 | int is_active = ctx->is_active; |
c994d613 PZ |
3800 | u64 now; |
3801 | ||
3802 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3803 | |
5b0311e1 | 3804 | if (likely(!ctx->nr_events)) |
facc4307 | 3805 | return; |
5b0311e1 | 3806 | |
3cbaa590 | 3807 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3808 | if (ctx->task) { |
3809 | if (!is_active) | |
3810 | cpuctx->task_ctx = ctx; | |
3811 | else | |
3812 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3813 | } | |
3814 | ||
3cbaa590 PZ |
3815 | is_active ^= ctx->is_active; /* changed bits */ |
3816 | ||
3817 | if (is_active & EVENT_TIME) { | |
3818 | /* start ctx time */ | |
3819 | now = perf_clock(); | |
3820 | ctx->timestamp = now; | |
3821 | perf_cgroup_set_timestamp(task, ctx); | |
3822 | } | |
3823 | ||
5b0311e1 FW |
3824 | /* |
3825 | * First go through the list and put on any pinned groups | |
3826 | * in order to give them the best chance of going on. | |
3827 | */ | |
3cbaa590 | 3828 | if (is_active & EVENT_PINNED) |
6e37738a | 3829 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3830 | |
3831 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3832 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3833 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3834 | } |
3835 | ||
329c0e01 | 3836 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3837 | enum event_type_t event_type, |
3838 | struct task_struct *task) | |
329c0e01 FW |
3839 | { |
3840 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3841 | ||
e5d1367f | 3842 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3843 | } |
3844 | ||
e5d1367f SE |
3845 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3846 | struct task_struct *task) | |
235c7fc7 | 3847 | { |
108b02cf | 3848 | struct perf_cpu_context *cpuctx; |
012669c7 | 3849 | struct pmu *pmu; |
235c7fc7 | 3850 | |
108b02cf | 3851 | cpuctx = __get_cpu_context(ctx); |
012669c7 PZ |
3852 | |
3853 | /* | |
3854 | * HACK: for HETEROGENEOUS the task context might have switched to a | |
3855 | * different PMU, force (re)set the context, | |
3856 | */ | |
3857 | pmu = ctx->pmu = cpuctx->ctx.pmu; | |
3858 | ||
556cccad KL |
3859 | if (cpuctx->task_ctx == ctx) { |
3860 | if (cpuctx->sched_cb_usage) | |
3861 | __perf_pmu_sched_task(cpuctx, true); | |
329c0e01 | 3862 | return; |
556cccad | 3863 | } |
329c0e01 | 3864 | |
facc4307 | 3865 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3866 | /* |
3867 | * We must check ctx->nr_events while holding ctx->lock, such | |
3868 | * that we serialize against perf_install_in_context(). | |
3869 | */ | |
3870 | if (!ctx->nr_events) | |
3871 | goto unlock; | |
3872 | ||
556cccad | 3873 | perf_pmu_disable(pmu); |
329c0e01 FW |
3874 | /* |
3875 | * We want to keep the following priority order: | |
3876 | * cpu pinned (that don't need to move), task pinned, | |
3877 | * cpu flexible, task flexible. | |
fe45bafb AS |
3878 | * |
3879 | * However, if task's ctx is not carrying any pinned | |
3880 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3881 | */ |
8e1a2031 | 3882 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3883 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3884 | perf_event_sched_in(cpuctx, ctx, task); |
556cccad KL |
3885 | |
3886 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3887 | pmu->sched_task(cpuctx->task_ctx, true); | |
3888 | ||
3889 | perf_pmu_enable(pmu); | |
fdccc3fb | 3890 | |
3891 | unlock: | |
facc4307 | 3892 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3893 | } |
3894 | ||
8dc85d54 PZ |
3895 | /* |
3896 | * Called from scheduler to add the events of the current task | |
3897 | * with interrupts disabled. | |
3898 | * | |
3899 | * We restore the event value and then enable it. | |
3900 | * | |
3901 | * This does not protect us against NMI, but enable() | |
3902 | * sets the enabled bit in the control field of event _before_ | |
3903 | * accessing the event control register. If a NMI hits, then it will | |
3904 | * keep the event running. | |
3905 | */ | |
ab0cce56 JO |
3906 | void __perf_event_task_sched_in(struct task_struct *prev, |
3907 | struct task_struct *task) | |
8dc85d54 PZ |
3908 | { |
3909 | struct perf_event_context *ctx; | |
3910 | int ctxn; | |
3911 | ||
7e41d177 PZ |
3912 | /* |
3913 | * If cgroup events exist on this CPU, then we need to check if we have | |
3914 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3915 | * | |
3916 | * Since cgroup events are CPU events, we must schedule these in before | |
3917 | * we schedule in the task events. | |
3918 | */ | |
3919 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3920 | perf_cgroup_sched_in(prev, task); | |
3921 | ||
8dc85d54 PZ |
3922 | for_each_task_context_nr(ctxn) { |
3923 | ctx = task->perf_event_ctxp[ctxn]; | |
3924 | if (likely(!ctx)) | |
3925 | continue; | |
3926 | ||
e5d1367f | 3927 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3928 | } |
d010b332 | 3929 | |
45ac1403 AH |
3930 | if (atomic_read(&nr_switch_events)) |
3931 | perf_event_switch(task, prev, true); | |
a5398bff KL |
3932 | |
3933 | if (__this_cpu_read(perf_sched_cb_usages)) | |
3934 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3935 | } |
3936 | ||
abd50713 PZ |
3937 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3938 | { | |
3939 | u64 frequency = event->attr.sample_freq; | |
3940 | u64 sec = NSEC_PER_SEC; | |
3941 | u64 divisor, dividend; | |
3942 | ||
3943 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3944 | ||
3945 | count_fls = fls64(count); | |
3946 | nsec_fls = fls64(nsec); | |
3947 | frequency_fls = fls64(frequency); | |
3948 | sec_fls = 30; | |
3949 | ||
3950 | /* | |
3951 | * We got @count in @nsec, with a target of sample_freq HZ | |
3952 | * the target period becomes: | |
3953 | * | |
3954 | * @count * 10^9 | |
3955 | * period = ------------------- | |
3956 | * @nsec * sample_freq | |
3957 | * | |
3958 | */ | |
3959 | ||
3960 | /* | |
3961 | * Reduce accuracy by one bit such that @a and @b converge | |
3962 | * to a similar magnitude. | |
3963 | */ | |
fe4b04fa | 3964 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3965 | do { \ |
3966 | if (a##_fls > b##_fls) { \ | |
3967 | a >>= 1; \ | |
3968 | a##_fls--; \ | |
3969 | } else { \ | |
3970 | b >>= 1; \ | |
3971 | b##_fls--; \ | |
3972 | } \ | |
3973 | } while (0) | |
3974 | ||
3975 | /* | |
3976 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3977 | * the other, so that finally we can do a u64/u64 division. | |
3978 | */ | |
3979 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3980 | REDUCE_FLS(nsec, frequency); | |
3981 | REDUCE_FLS(sec, count); | |
3982 | } | |
3983 | ||
3984 | if (count_fls + sec_fls > 64) { | |
3985 | divisor = nsec * frequency; | |
3986 | ||
3987 | while (count_fls + sec_fls > 64) { | |
3988 | REDUCE_FLS(count, sec); | |
3989 | divisor >>= 1; | |
3990 | } | |
3991 | ||
3992 | dividend = count * sec; | |
3993 | } else { | |
3994 | dividend = count * sec; | |
3995 | ||
3996 | while (nsec_fls + frequency_fls > 64) { | |
3997 | REDUCE_FLS(nsec, frequency); | |
3998 | dividend >>= 1; | |
3999 | } | |
4000 | ||
4001 | divisor = nsec * frequency; | |
4002 | } | |
4003 | ||
f6ab91ad PZ |
4004 | if (!divisor) |
4005 | return dividend; | |
4006 | ||
abd50713 PZ |
4007 | return div64_u64(dividend, divisor); |
4008 | } | |
4009 | ||
e050e3f0 SE |
4010 | static DEFINE_PER_CPU(int, perf_throttled_count); |
4011 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
4012 | ||
f39d47ff | 4013 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 4014 | { |
cdd6c482 | 4015 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 4016 | s64 period, sample_period; |
bd2b5b12 PZ |
4017 | s64 delta; |
4018 | ||
abd50713 | 4019 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
4020 | |
4021 | delta = (s64)(period - hwc->sample_period); | |
4022 | delta = (delta + 7) / 8; /* low pass filter */ | |
4023 | ||
4024 | sample_period = hwc->sample_period + delta; | |
4025 | ||
4026 | if (!sample_period) | |
4027 | sample_period = 1; | |
4028 | ||
bd2b5b12 | 4029 | hwc->sample_period = sample_period; |
abd50713 | 4030 | |
e7850595 | 4031 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
4032 | if (disable) |
4033 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4034 | ||
e7850595 | 4035 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
4036 | |
4037 | if (disable) | |
4038 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 4039 | } |
bd2b5b12 PZ |
4040 | } |
4041 | ||
e050e3f0 SE |
4042 | /* |
4043 | * combine freq adjustment with unthrottling to avoid two passes over the | |
4044 | * events. At the same time, make sure, having freq events does not change | |
4045 | * the rate of unthrottling as that would introduce bias. | |
4046 | */ | |
4047 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
4048 | int needs_unthr) | |
60db5e09 | 4049 | { |
cdd6c482 IM |
4050 | struct perf_event *event; |
4051 | struct hw_perf_event *hwc; | |
e050e3f0 | 4052 | u64 now, period = TICK_NSEC; |
abd50713 | 4053 | s64 delta; |
60db5e09 | 4054 | |
e050e3f0 SE |
4055 | /* |
4056 | * only need to iterate over all events iff: | |
4057 | * - context have events in frequency mode (needs freq adjust) | |
4058 | * - there are events to unthrottle on this cpu | |
4059 | */ | |
4060 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
4061 | return; |
4062 | ||
e050e3f0 | 4063 | raw_spin_lock(&ctx->lock); |
f39d47ff | 4064 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 4065 | |
03541f8b | 4066 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 4067 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
4068 | continue; |
4069 | ||
5632ab12 | 4070 | if (!event_filter_match(event)) |
5d27c23d PZ |
4071 | continue; |
4072 | ||
44377277 AS |
4073 | perf_pmu_disable(event->pmu); |
4074 | ||
cdd6c482 | 4075 | hwc = &event->hw; |
6a24ed6c | 4076 | |
ae23bff1 | 4077 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 4078 | hwc->interrupts = 0; |
cdd6c482 | 4079 | perf_log_throttle(event, 1); |
a4eaf7f1 | 4080 | event->pmu->start(event, 0); |
a78ac325 PZ |
4081 | } |
4082 | ||
cdd6c482 | 4083 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 4084 | goto next; |
60db5e09 | 4085 | |
e050e3f0 SE |
4086 | /* |
4087 | * stop the event and update event->count | |
4088 | */ | |
4089 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4090 | ||
e7850595 | 4091 | now = local64_read(&event->count); |
abd50713 PZ |
4092 | delta = now - hwc->freq_count_stamp; |
4093 | hwc->freq_count_stamp = now; | |
60db5e09 | 4094 | |
e050e3f0 SE |
4095 | /* |
4096 | * restart the event | |
4097 | * reload only if value has changed | |
f39d47ff SE |
4098 | * we have stopped the event so tell that |
4099 | * to perf_adjust_period() to avoid stopping it | |
4100 | * twice. | |
e050e3f0 | 4101 | */ |
abd50713 | 4102 | if (delta > 0) |
f39d47ff | 4103 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
4104 | |
4105 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
4106 | next: |
4107 | perf_pmu_enable(event->pmu); | |
60db5e09 | 4108 | } |
e050e3f0 | 4109 | |
f39d47ff | 4110 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 4111 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
4112 | } |
4113 | ||
235c7fc7 | 4114 | /* |
8703a7cf | 4115 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 4116 | */ |
8703a7cf | 4117 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 4118 | { |
dddd3379 TG |
4119 | /* |
4120 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
4121 | * disabled by the inheritance code. | |
4122 | */ | |
8703a7cf PZ |
4123 | if (ctx->rotate_disable) |
4124 | return; | |
8e1a2031 | 4125 | |
8703a7cf PZ |
4126 | perf_event_groups_delete(&ctx->flexible_groups, event); |
4127 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
4128 | } |
4129 | ||
7fa343b7 | 4130 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 4131 | static inline struct perf_event * |
7fa343b7 | 4132 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 4133 | { |
7fa343b7 SL |
4134 | struct perf_event *event; |
4135 | ||
4136 | /* pick the first active flexible event */ | |
4137 | event = list_first_entry_or_null(&ctx->flexible_active, | |
4138 | struct perf_event, active_list); | |
4139 | ||
4140 | /* if no active flexible event, pick the first event */ | |
4141 | if (!event) { | |
4142 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
4143 | typeof(*event), group_node); | |
4144 | } | |
4145 | ||
90c91dfb PZ |
4146 | /* |
4147 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
4148 | * finds there are unschedulable events, it will set it again. | |
4149 | */ | |
4150 | ctx->rotate_necessary = 0; | |
4151 | ||
7fa343b7 | 4152 | return event; |
8d5bce0c PZ |
4153 | } |
4154 | ||
4155 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4156 | { | |
4157 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4158 | struct perf_event_context *task_ctx = NULL; |
4159 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4160 | |
4161 | /* | |
4162 | * Since we run this from IRQ context, nobody can install new | |
4163 | * events, thus the event count values are stable. | |
4164 | */ | |
7fc23a53 | 4165 | |
fd7d5517 IR |
4166 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4167 | task_ctx = cpuctx->task_ctx; | |
4168 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4169 | |
8d5bce0c PZ |
4170 | if (!(cpu_rotate || task_rotate)) |
4171 | return false; | |
0f5a2601 | 4172 | |
facc4307 | 4173 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4174 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4175 | |
8d5bce0c | 4176 | if (task_rotate) |
7fa343b7 | 4177 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4178 | if (cpu_rotate) |
7fa343b7 | 4179 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4180 | |
8d5bce0c PZ |
4181 | /* |
4182 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4183 | * and then, if needed CPU flexible. | |
4184 | */ | |
fd7d5517 IR |
4185 | if (task_event || (task_ctx && cpu_event)) |
4186 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4187 | if (cpu_event) |
4188 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4189 | |
8d5bce0c | 4190 | if (task_event) |
fd7d5517 | 4191 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4192 | if (cpu_event) |
4193 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4194 | |
fd7d5517 | 4195 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4196 | |
0f5a2601 PZ |
4197 | perf_pmu_enable(cpuctx->ctx.pmu); |
4198 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4199 | |
8d5bce0c | 4200 | return true; |
e9d2b064 PZ |
4201 | } |
4202 | ||
4203 | void perf_event_task_tick(void) | |
4204 | { | |
2fde4f94 MR |
4205 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4206 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4207 | int throttled; |
b5ab4cd5 | 4208 | |
16444645 | 4209 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4210 | |
e050e3f0 SE |
4211 | __this_cpu_inc(perf_throttled_seq); |
4212 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4213 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4214 | |
2fde4f94 | 4215 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4216 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4217 | } |
4218 | ||
889ff015 FW |
4219 | static int event_enable_on_exec(struct perf_event *event, |
4220 | struct perf_event_context *ctx) | |
4221 | { | |
4222 | if (!event->attr.enable_on_exec) | |
4223 | return 0; | |
4224 | ||
4225 | event->attr.enable_on_exec = 0; | |
4226 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4227 | return 0; | |
4228 | ||
0d3d73aa | 4229 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4230 | |
4231 | return 1; | |
4232 | } | |
4233 | ||
57e7986e | 4234 | /* |
cdd6c482 | 4235 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4236 | * This expects task == current. |
4237 | */ | |
c1274499 | 4238 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4239 | { |
c1274499 | 4240 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4241 | enum event_type_t event_type = 0; |
3e349507 | 4242 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4243 | struct perf_event *event; |
57e7986e PM |
4244 | unsigned long flags; |
4245 | int enabled = 0; | |
4246 | ||
4247 | local_irq_save(flags); | |
c1274499 | 4248 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4249 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4250 | goto out; |
4251 | ||
3e349507 PZ |
4252 | cpuctx = __get_cpu_context(ctx); |
4253 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4254 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4255 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4256 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4257 | event_type |= get_event_type(event); |
4258 | } | |
57e7986e PM |
4259 | |
4260 | /* | |
3e349507 | 4261 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4262 | */ |
3e349507 | 4263 | if (enabled) { |
211de6eb | 4264 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4265 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4266 | } else { |
4267 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4268 | } |
4269 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4270 | |
9ed6060d | 4271 | out: |
57e7986e | 4272 | local_irq_restore(flags); |
211de6eb PZ |
4273 | |
4274 | if (clone_ctx) | |
4275 | put_ctx(clone_ctx); | |
57e7986e PM |
4276 | } |
4277 | ||
2e498d0a ME |
4278 | static void perf_remove_from_owner(struct perf_event *event); |
4279 | static void perf_event_exit_event(struct perf_event *event, | |
4280 | struct perf_event_context *ctx); | |
4281 | ||
4282 | /* | |
4283 | * Removes all events from the current task that have been marked | |
4284 | * remove-on-exec, and feeds their values back to parent events. | |
4285 | */ | |
4286 | static void perf_event_remove_on_exec(int ctxn) | |
4287 | { | |
4288 | struct perf_event_context *ctx, *clone_ctx = NULL; | |
4289 | struct perf_event *event, *next; | |
4290 | LIST_HEAD(free_list); | |
4291 | unsigned long flags; | |
4292 | bool modified = false; | |
4293 | ||
4294 | ctx = perf_pin_task_context(current, ctxn); | |
4295 | if (!ctx) | |
4296 | return; | |
4297 | ||
4298 | mutex_lock(&ctx->mutex); | |
4299 | ||
4300 | if (WARN_ON_ONCE(ctx->task != current)) | |
4301 | goto unlock; | |
4302 | ||
4303 | list_for_each_entry_safe(event, next, &ctx->event_list, event_entry) { | |
4304 | if (!event->attr.remove_on_exec) | |
4305 | continue; | |
4306 | ||
4307 | if (!is_kernel_event(event)) | |
4308 | perf_remove_from_owner(event); | |
4309 | ||
4310 | modified = true; | |
4311 | ||
4312 | perf_event_exit_event(event, ctx); | |
4313 | } | |
4314 | ||
4315 | raw_spin_lock_irqsave(&ctx->lock, flags); | |
4316 | if (modified) | |
4317 | clone_ctx = unclone_ctx(ctx); | |
4318 | --ctx->pin_count; | |
4319 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4320 | ||
4321 | unlock: | |
4322 | mutex_unlock(&ctx->mutex); | |
4323 | ||
4324 | put_ctx(ctx); | |
4325 | if (clone_ctx) | |
4326 | put_ctx(clone_ctx); | |
4327 | } | |
4328 | ||
0492d4c5 PZ |
4329 | struct perf_read_data { |
4330 | struct perf_event *event; | |
4331 | bool group; | |
7d88962e | 4332 | int ret; |
0492d4c5 PZ |
4333 | }; |
4334 | ||
451d24d1 | 4335 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4336 | { |
d6a2f903 DCC |
4337 | u16 local_pkg, event_pkg; |
4338 | ||
4339 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4340 | int local_cpu = smp_processor_id(); |
4341 | ||
4342 | event_pkg = topology_physical_package_id(event_cpu); | |
4343 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4344 | |
4345 | if (event_pkg == local_pkg) | |
4346 | return local_cpu; | |
4347 | } | |
4348 | ||
4349 | return event_cpu; | |
4350 | } | |
4351 | ||
0793a61d | 4352 | /* |
cdd6c482 | 4353 | * Cross CPU call to read the hardware event |
0793a61d | 4354 | */ |
cdd6c482 | 4355 | static void __perf_event_read(void *info) |
0793a61d | 4356 | { |
0492d4c5 PZ |
4357 | struct perf_read_data *data = info; |
4358 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4359 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4360 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4361 | struct pmu *pmu = event->pmu; |
621a01ea | 4362 | |
e1ac3614 PM |
4363 | /* |
4364 | * If this is a task context, we need to check whether it is | |
4365 | * the current task context of this cpu. If not it has been | |
4366 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4367 | * event->count would have been updated to a recent sample |
4368 | * when the event was scheduled out. | |
e1ac3614 PM |
4369 | */ |
4370 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4371 | return; | |
4372 | ||
e625cce1 | 4373 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4374 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4375 | update_context_time(ctx); |
e5d1367f SE |
4376 | update_cgrp_time_from_event(event); |
4377 | } | |
0492d4c5 | 4378 | |
0d3d73aa PZ |
4379 | perf_event_update_time(event); |
4380 | if (data->group) | |
4381 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4382 | |
4a00c16e SB |
4383 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4384 | goto unlock; | |
0492d4c5 | 4385 | |
4a00c16e SB |
4386 | if (!data->group) { |
4387 | pmu->read(event); | |
4388 | data->ret = 0; | |
0492d4c5 | 4389 | goto unlock; |
4a00c16e SB |
4390 | } |
4391 | ||
4392 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4393 | ||
4394 | pmu->read(event); | |
0492d4c5 | 4395 | |
edb39592 | 4396 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4397 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4398 | /* | |
4399 | * Use sibling's PMU rather than @event's since | |
4400 | * sibling could be on different (eg: software) PMU. | |
4401 | */ | |
0492d4c5 | 4402 | sub->pmu->read(sub); |
4a00c16e | 4403 | } |
0492d4c5 | 4404 | } |
4a00c16e SB |
4405 | |
4406 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4407 | |
4408 | unlock: | |
e625cce1 | 4409 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4410 | } |
4411 | ||
b5e58793 PZ |
4412 | static inline u64 perf_event_count(struct perf_event *event) |
4413 | { | |
c39a0e2c | 4414 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4415 | } |
4416 | ||
ffe8690c KX |
4417 | /* |
4418 | * NMI-safe method to read a local event, that is an event that | |
4419 | * is: | |
4420 | * - either for the current task, or for this CPU | |
4421 | * - does not have inherit set, for inherited task events | |
4422 | * will not be local and we cannot read them atomically | |
4423 | * - must not have a pmu::count method | |
4424 | */ | |
7d9285e8 YS |
4425 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4426 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4427 | { |
4428 | unsigned long flags; | |
f91840a3 | 4429 | int ret = 0; |
ffe8690c KX |
4430 | |
4431 | /* | |
4432 | * Disabling interrupts avoids all counter scheduling (context | |
4433 | * switches, timer based rotation and IPIs). | |
4434 | */ | |
4435 | local_irq_save(flags); | |
4436 | ||
ffe8690c KX |
4437 | /* |
4438 | * It must not be an event with inherit set, we cannot read | |
4439 | * all child counters from atomic context. | |
4440 | */ | |
f91840a3 AS |
4441 | if (event->attr.inherit) { |
4442 | ret = -EOPNOTSUPP; | |
4443 | goto out; | |
4444 | } | |
ffe8690c | 4445 | |
f91840a3 AS |
4446 | /* If this is a per-task event, it must be for current */ |
4447 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4448 | event->hw.target != current) { | |
4449 | ret = -EINVAL; | |
4450 | goto out; | |
4451 | } | |
4452 | ||
4453 | /* If this is a per-CPU event, it must be for this CPU */ | |
4454 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4455 | event->cpu != smp_processor_id()) { | |
4456 | ret = -EINVAL; | |
4457 | goto out; | |
4458 | } | |
ffe8690c | 4459 | |
befb1b3c RC |
4460 | /* If this is a pinned event it must be running on this CPU */ |
4461 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4462 | ret = -EBUSY; | |
4463 | goto out; | |
4464 | } | |
4465 | ||
ffe8690c KX |
4466 | /* |
4467 | * If the event is currently on this CPU, its either a per-task event, | |
4468 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4469 | * oncpu == -1). | |
4470 | */ | |
4471 | if (event->oncpu == smp_processor_id()) | |
4472 | event->pmu->read(event); | |
4473 | ||
f91840a3 | 4474 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4475 | if (enabled || running) { |
4476 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4477 | u64 __enabled, __running; | |
4478 | ||
4479 | __perf_update_times(event, now, &__enabled, &__running); | |
4480 | if (enabled) | |
4481 | *enabled = __enabled; | |
4482 | if (running) | |
4483 | *running = __running; | |
4484 | } | |
f91840a3 | 4485 | out: |
ffe8690c KX |
4486 | local_irq_restore(flags); |
4487 | ||
f91840a3 | 4488 | return ret; |
ffe8690c KX |
4489 | } |
4490 | ||
7d88962e | 4491 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4492 | { |
0c1cbc18 | 4493 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4494 | int event_cpu, ret = 0; |
7d88962e | 4495 | |
0793a61d | 4496 | /* |
cdd6c482 IM |
4497 | * If event is enabled and currently active on a CPU, update the |
4498 | * value in the event structure: | |
0793a61d | 4499 | */ |
0c1cbc18 PZ |
4500 | again: |
4501 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4502 | struct perf_read_data data; | |
4503 | ||
4504 | /* | |
4505 | * Orders the ->state and ->oncpu loads such that if we see | |
4506 | * ACTIVE we must also see the right ->oncpu. | |
4507 | * | |
4508 | * Matches the smp_wmb() from event_sched_in(). | |
4509 | */ | |
4510 | smp_rmb(); | |
d6a2f903 | 4511 | |
451d24d1 PZ |
4512 | event_cpu = READ_ONCE(event->oncpu); |
4513 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4514 | return 0; | |
4515 | ||
0c1cbc18 PZ |
4516 | data = (struct perf_read_data){ |
4517 | .event = event, | |
4518 | .group = group, | |
4519 | .ret = 0, | |
4520 | }; | |
4521 | ||
451d24d1 PZ |
4522 | preempt_disable(); |
4523 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4524 | |
58763148 PZ |
4525 | /* |
4526 | * Purposely ignore the smp_call_function_single() return | |
4527 | * value. | |
4528 | * | |
451d24d1 | 4529 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4530 | * scheduled out and that will have updated the event count. |
4531 | * | |
4532 | * Therefore, either way, we'll have an up-to-date event count | |
4533 | * after this. | |
4534 | */ | |
451d24d1 PZ |
4535 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4536 | preempt_enable(); | |
58763148 | 4537 | ret = data.ret; |
0c1cbc18 PZ |
4538 | |
4539 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4540 | struct perf_event_context *ctx = event->ctx; |
4541 | unsigned long flags; | |
4542 | ||
e625cce1 | 4543 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4544 | state = event->state; |
4545 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4546 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4547 | goto again; | |
4548 | } | |
4549 | ||
c530ccd9 | 4550 | /* |
0c1cbc18 PZ |
4551 | * May read while context is not active (e.g., thread is |
4552 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4553 | */ |
0c1cbc18 | 4554 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4555 | update_context_time(ctx); |
e5d1367f SE |
4556 | update_cgrp_time_from_event(event); |
4557 | } | |
0c1cbc18 | 4558 | |
0d3d73aa | 4559 | perf_event_update_time(event); |
0492d4c5 | 4560 | if (group) |
0d3d73aa | 4561 | perf_event_update_sibling_time(event); |
e625cce1 | 4562 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4563 | } |
7d88962e SB |
4564 | |
4565 | return ret; | |
0793a61d TG |
4566 | } |
4567 | ||
a63eaf34 | 4568 | /* |
cdd6c482 | 4569 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4570 | */ |
eb184479 | 4571 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4572 | { |
e625cce1 | 4573 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4574 | mutex_init(&ctx->mutex); |
2fde4f94 | 4575 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4576 | perf_event_groups_init(&ctx->pinned_groups); |
4577 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4578 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4579 | INIT_LIST_HEAD(&ctx->pinned_active); |
4580 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4581 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4582 | } |
4583 | ||
4584 | static struct perf_event_context * | |
4585 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4586 | { | |
4587 | struct perf_event_context *ctx; | |
4588 | ||
4589 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4590 | if (!ctx) | |
4591 | return NULL; | |
4592 | ||
4593 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4594 | if (task) |
4595 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4596 | ctx->pmu = pmu; |
4597 | ||
4598 | return ctx; | |
a63eaf34 PM |
4599 | } |
4600 | ||
2ebd4ffb MH |
4601 | static struct task_struct * |
4602 | find_lively_task_by_vpid(pid_t vpid) | |
4603 | { | |
4604 | struct task_struct *task; | |
0793a61d TG |
4605 | |
4606 | rcu_read_lock(); | |
2ebd4ffb | 4607 | if (!vpid) |
0793a61d TG |
4608 | task = current; |
4609 | else | |
2ebd4ffb | 4610 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4611 | if (task) |
4612 | get_task_struct(task); | |
4613 | rcu_read_unlock(); | |
4614 | ||
4615 | if (!task) | |
4616 | return ERR_PTR(-ESRCH); | |
4617 | ||
2ebd4ffb | 4618 | return task; |
2ebd4ffb MH |
4619 | } |
4620 | ||
fe4b04fa PZ |
4621 | /* |
4622 | * Returns a matching context with refcount and pincount. | |
4623 | */ | |
108b02cf | 4624 | static struct perf_event_context * |
4af57ef2 YZ |
4625 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4626 | struct perf_event *event) | |
0793a61d | 4627 | { |
211de6eb | 4628 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4629 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4630 | void *task_ctx_data = NULL; |
25346b93 | 4631 | unsigned long flags; |
8dc85d54 | 4632 | int ctxn, err; |
4af57ef2 | 4633 | int cpu = event->cpu; |
0793a61d | 4634 | |
22a4ec72 | 4635 | if (!task) { |
cdd6c482 | 4636 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4637 | err = perf_allow_cpu(&event->attr); |
4638 | if (err) | |
4639 | return ERR_PTR(err); | |
0793a61d | 4640 | |
108b02cf | 4641 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4642 | ctx = &cpuctx->ctx; |
c93f7669 | 4643 | get_ctx(ctx); |
6c605f83 | 4644 | raw_spin_lock_irqsave(&ctx->lock, flags); |
fe4b04fa | 4645 | ++ctx->pin_count; |
6c605f83 | 4646 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4647 | |
0793a61d TG |
4648 | return ctx; |
4649 | } | |
4650 | ||
8dc85d54 PZ |
4651 | err = -EINVAL; |
4652 | ctxn = pmu->task_ctx_nr; | |
4653 | if (ctxn < 0) | |
4654 | goto errout; | |
4655 | ||
4af57ef2 | 4656 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
ff9ff926 | 4657 | task_ctx_data = alloc_task_ctx_data(pmu); |
4af57ef2 YZ |
4658 | if (!task_ctx_data) { |
4659 | err = -ENOMEM; | |
4660 | goto errout; | |
4661 | } | |
4662 | } | |
4663 | ||
9ed6060d | 4664 | retry: |
8dc85d54 | 4665 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4666 | if (ctx) { |
211de6eb | 4667 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4668 | ++ctx->pin_count; |
4af57ef2 YZ |
4669 | |
4670 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4671 | ctx->task_ctx_data = task_ctx_data; | |
4672 | task_ctx_data = NULL; | |
4673 | } | |
e625cce1 | 4674 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4675 | |
4676 | if (clone_ctx) | |
4677 | put_ctx(clone_ctx); | |
9137fb28 | 4678 | } else { |
eb184479 | 4679 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4680 | err = -ENOMEM; |
4681 | if (!ctx) | |
4682 | goto errout; | |
eb184479 | 4683 | |
4af57ef2 YZ |
4684 | if (task_ctx_data) { |
4685 | ctx->task_ctx_data = task_ctx_data; | |
4686 | task_ctx_data = NULL; | |
4687 | } | |
4688 | ||
dbe08d82 ON |
4689 | err = 0; |
4690 | mutex_lock(&task->perf_event_mutex); | |
4691 | /* | |
4692 | * If it has already passed perf_event_exit_task(). | |
4693 | * we must see PF_EXITING, it takes this mutex too. | |
4694 | */ | |
4695 | if (task->flags & PF_EXITING) | |
4696 | err = -ESRCH; | |
4697 | else if (task->perf_event_ctxp[ctxn]) | |
4698 | err = -EAGAIN; | |
fe4b04fa | 4699 | else { |
9137fb28 | 4700 | get_ctx(ctx); |
fe4b04fa | 4701 | ++ctx->pin_count; |
dbe08d82 | 4702 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4703 | } |
dbe08d82 ON |
4704 | mutex_unlock(&task->perf_event_mutex); |
4705 | ||
4706 | if (unlikely(err)) { | |
9137fb28 | 4707 | put_ctx(ctx); |
dbe08d82 ON |
4708 | |
4709 | if (err == -EAGAIN) | |
4710 | goto retry; | |
4711 | goto errout; | |
a63eaf34 PM |
4712 | } |
4713 | } | |
4714 | ||
ff9ff926 | 4715 | free_task_ctx_data(pmu, task_ctx_data); |
0793a61d | 4716 | return ctx; |
c93f7669 | 4717 | |
9ed6060d | 4718 | errout: |
ff9ff926 | 4719 | free_task_ctx_data(pmu, task_ctx_data); |
c93f7669 | 4720 | return ERR_PTR(err); |
0793a61d TG |
4721 | } |
4722 | ||
6fb2915d LZ |
4723 | static void perf_event_free_filter(struct perf_event *event); |
4724 | ||
cdd6c482 | 4725 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4726 | { |
cdd6c482 | 4727 | struct perf_event *event; |
592903cd | 4728 | |
cdd6c482 IM |
4729 | event = container_of(head, struct perf_event, rcu_head); |
4730 | if (event->ns) | |
4731 | put_pid_ns(event->ns); | |
6fb2915d | 4732 | perf_event_free_filter(event); |
bdacfaf2 | 4733 | kmem_cache_free(perf_event_cache, event); |
592903cd PZ |
4734 | } |
4735 | ||
b69cf536 | 4736 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4737 | struct perf_buffer *rb); |
925d519a | 4738 | |
f2fb6bef KL |
4739 | static void detach_sb_event(struct perf_event *event) |
4740 | { | |
4741 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4742 | ||
4743 | raw_spin_lock(&pel->lock); | |
4744 | list_del_rcu(&event->sb_list); | |
4745 | raw_spin_unlock(&pel->lock); | |
4746 | } | |
4747 | ||
a4f144eb | 4748 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4749 | { |
a4f144eb DCC |
4750 | struct perf_event_attr *attr = &event->attr; |
4751 | ||
f2fb6bef | 4752 | if (event->parent) |
a4f144eb | 4753 | return false; |
f2fb6bef KL |
4754 | |
4755 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4756 | return false; |
f2fb6bef | 4757 | |
a4f144eb DCC |
4758 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4759 | attr->comm || attr->comm_exec || | |
76193a94 | 4760 | attr->task || attr->ksymbol || |
e17d43b9 | 4761 | attr->context_switch || attr->text_poke || |
21038f2b | 4762 | attr->bpf_event) |
a4f144eb DCC |
4763 | return true; |
4764 | return false; | |
4765 | } | |
4766 | ||
4767 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4768 | { | |
4769 | if (is_sb_event(event)) | |
4770 | detach_sb_event(event); | |
f2fb6bef KL |
4771 | } |
4772 | ||
4beb31f3 | 4773 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4774 | { |
4beb31f3 FW |
4775 | if (event->parent) |
4776 | return; | |
4777 | ||
4beb31f3 FW |
4778 | if (is_cgroup_event(event)) |
4779 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4780 | } | |
925d519a | 4781 | |
555e0c1e FW |
4782 | #ifdef CONFIG_NO_HZ_FULL |
4783 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4784 | #endif | |
4785 | ||
4786 | static void unaccount_freq_event_nohz(void) | |
4787 | { | |
4788 | #ifdef CONFIG_NO_HZ_FULL | |
4789 | spin_lock(&nr_freq_lock); | |
4790 | if (atomic_dec_and_test(&nr_freq_events)) | |
4791 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4792 | spin_unlock(&nr_freq_lock); | |
4793 | #endif | |
4794 | } | |
4795 | ||
4796 | static void unaccount_freq_event(void) | |
4797 | { | |
4798 | if (tick_nohz_full_enabled()) | |
4799 | unaccount_freq_event_nohz(); | |
4800 | else | |
4801 | atomic_dec(&nr_freq_events); | |
4802 | } | |
4803 | ||
4beb31f3 FW |
4804 | static void unaccount_event(struct perf_event *event) |
4805 | { | |
25432ae9 PZ |
4806 | bool dec = false; |
4807 | ||
4beb31f3 FW |
4808 | if (event->parent) |
4809 | return; | |
4810 | ||
a5398bff | 4811 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 4812 | dec = true; |
4beb31f3 FW |
4813 | if (event->attr.mmap || event->attr.mmap_data) |
4814 | atomic_dec(&nr_mmap_events); | |
88a16a13 JO |
4815 | if (event->attr.build_id) |
4816 | atomic_dec(&nr_build_id_events); | |
4beb31f3 FW |
4817 | if (event->attr.comm) |
4818 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4819 | if (event->attr.namespaces) |
4820 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4821 | if (event->attr.cgroup) |
4822 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4823 | if (event->attr.task) |
4824 | atomic_dec(&nr_task_events); | |
948b26b6 | 4825 | if (event->attr.freq) |
555e0c1e | 4826 | unaccount_freq_event(); |
45ac1403 | 4827 | if (event->attr.context_switch) { |
25432ae9 | 4828 | dec = true; |
45ac1403 AH |
4829 | atomic_dec(&nr_switch_events); |
4830 | } | |
4beb31f3 | 4831 | if (is_cgroup_event(event)) |
25432ae9 | 4832 | dec = true; |
4beb31f3 | 4833 | if (has_branch_stack(event)) |
25432ae9 | 4834 | dec = true; |
76193a94 SL |
4835 | if (event->attr.ksymbol) |
4836 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4837 | if (event->attr.bpf_event) |
4838 | atomic_dec(&nr_bpf_events); | |
e17d43b9 AH |
4839 | if (event->attr.text_poke) |
4840 | atomic_dec(&nr_text_poke_events); | |
25432ae9 | 4841 | |
9107c89e PZ |
4842 | if (dec) { |
4843 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4844 | schedule_delayed_work(&perf_sched_work, HZ); | |
4845 | } | |
4beb31f3 FW |
4846 | |
4847 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4848 | |
4849 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4850 | } |
925d519a | 4851 | |
9107c89e PZ |
4852 | static void perf_sched_delayed(struct work_struct *work) |
4853 | { | |
4854 | mutex_lock(&perf_sched_mutex); | |
4855 | if (atomic_dec_and_test(&perf_sched_count)) | |
4856 | static_branch_disable(&perf_sched_events); | |
4857 | mutex_unlock(&perf_sched_mutex); | |
4858 | } | |
4859 | ||
bed5b25a AS |
4860 | /* |
4861 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4862 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4863 | * at a time, so we disallow creating events that might conflict, namely: | |
4864 | * | |
4865 | * 1) cpu-wide events in the presence of per-task events, | |
4866 | * 2) per-task events in the presence of cpu-wide events, | |
4867 | * 3) two matching events on the same context. | |
4868 | * | |
4869 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4870 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4871 | */ |
4872 | static int exclusive_event_init(struct perf_event *event) | |
4873 | { | |
4874 | struct pmu *pmu = event->pmu; | |
4875 | ||
8a58ddae | 4876 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4877 | return 0; |
4878 | ||
4879 | /* | |
4880 | * Prevent co-existence of per-task and cpu-wide events on the | |
4881 | * same exclusive pmu. | |
4882 | * | |
4883 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4884 | * events on this "exclusive" pmu, positive means there are | |
4885 | * per-task events. | |
4886 | * | |
4887 | * Since this is called in perf_event_alloc() path, event::ctx | |
4888 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4889 | * to mean "per-task event", because unlike other attach states it | |
4890 | * never gets cleared. | |
4891 | */ | |
4892 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4893 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4894 | return -EBUSY; | |
4895 | } else { | |
4896 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4897 | return -EBUSY; | |
4898 | } | |
4899 | ||
4900 | return 0; | |
4901 | } | |
4902 | ||
4903 | static void exclusive_event_destroy(struct perf_event *event) | |
4904 | { | |
4905 | struct pmu *pmu = event->pmu; | |
4906 | ||
8a58ddae | 4907 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4908 | return; |
4909 | ||
4910 | /* see comment in exclusive_event_init() */ | |
4911 | if (event->attach_state & PERF_ATTACH_TASK) | |
4912 | atomic_dec(&pmu->exclusive_cnt); | |
4913 | else | |
4914 | atomic_inc(&pmu->exclusive_cnt); | |
4915 | } | |
4916 | ||
4917 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4918 | { | |
3bf6215a | 4919 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4920 | (e1->cpu == e2->cpu || |
4921 | e1->cpu == -1 || | |
4922 | e2->cpu == -1)) | |
4923 | return true; | |
4924 | return false; | |
4925 | } | |
4926 | ||
bed5b25a AS |
4927 | static bool exclusive_event_installable(struct perf_event *event, |
4928 | struct perf_event_context *ctx) | |
4929 | { | |
4930 | struct perf_event *iter_event; | |
4931 | struct pmu *pmu = event->pmu; | |
4932 | ||
8a58ddae AS |
4933 | lockdep_assert_held(&ctx->mutex); |
4934 | ||
4935 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4936 | return true; |
4937 | ||
4938 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4939 | if (exclusive_event_match(iter_event, event)) | |
4940 | return false; | |
4941 | } | |
4942 | ||
4943 | return true; | |
4944 | } | |
4945 | ||
375637bc AS |
4946 | static void perf_addr_filters_splice(struct perf_event *event, |
4947 | struct list_head *head); | |
4948 | ||
683ede43 | 4949 | static void _free_event(struct perf_event *event) |
f1600952 | 4950 | { |
e360adbe | 4951 | irq_work_sync(&event->pending); |
925d519a | 4952 | |
4beb31f3 | 4953 | unaccount_event(event); |
9ee318a7 | 4954 | |
da97e184 JFG |
4955 | security_perf_event_free(event); |
4956 | ||
76369139 | 4957 | if (event->rb) { |
9bb5d40c PZ |
4958 | /* |
4959 | * Can happen when we close an event with re-directed output. | |
4960 | * | |
4961 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4962 | * over us; possibly making our ring_buffer_put() the last. | |
4963 | */ | |
4964 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4965 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4966 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4967 | } |
4968 | ||
e5d1367f SE |
4969 | if (is_cgroup_event(event)) |
4970 | perf_detach_cgroup(event); | |
4971 | ||
a0733e69 PZ |
4972 | if (!event->parent) { |
4973 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4974 | put_callchain_buffers(); | |
4975 | } | |
4976 | ||
4977 | perf_event_free_bpf_prog(event); | |
375637bc | 4978 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4979 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4980 | |
4981 | if (event->destroy) | |
4982 | event->destroy(event); | |
4983 | ||
1cf8dfe8 PZ |
4984 | /* |
4985 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4986 | * hw.target. | |
4987 | */ | |
621b6d2e PB |
4988 | if (event->hw.target) |
4989 | put_task_struct(event->hw.target); | |
4990 | ||
1cf8dfe8 PZ |
4991 | /* |
4992 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4993 | * all task references must be cleaned up. | |
4994 | */ | |
4995 | if (event->ctx) | |
4996 | put_ctx(event->ctx); | |
4997 | ||
62a92c8f AS |
4998 | exclusive_event_destroy(event); |
4999 | module_put(event->pmu->module); | |
a0733e69 PZ |
5000 | |
5001 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
5002 | } |
5003 | ||
683ede43 PZ |
5004 | /* |
5005 | * Used to free events which have a known refcount of 1, such as in error paths | |
5006 | * where the event isn't exposed yet and inherited events. | |
5007 | */ | |
5008 | static void free_event(struct perf_event *event) | |
0793a61d | 5009 | { |
683ede43 PZ |
5010 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
5011 | "unexpected event refcount: %ld; ptr=%p\n", | |
5012 | atomic_long_read(&event->refcount), event)) { | |
5013 | /* leak to avoid use-after-free */ | |
5014 | return; | |
5015 | } | |
0793a61d | 5016 | |
683ede43 | 5017 | _free_event(event); |
0793a61d TG |
5018 | } |
5019 | ||
a66a3052 | 5020 | /* |
f8697762 | 5021 | * Remove user event from the owner task. |
a66a3052 | 5022 | */ |
f8697762 | 5023 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 5024 | { |
8882135b | 5025 | struct task_struct *owner; |
fb0459d7 | 5026 | |
8882135b | 5027 | rcu_read_lock(); |
8882135b | 5028 | /* |
f47c02c0 PZ |
5029 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
5030 | * observe !owner it means the list deletion is complete and we can | |
5031 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
5032 | * owner->perf_event_mutex. |
5033 | */ | |
506458ef | 5034 | owner = READ_ONCE(event->owner); |
8882135b PZ |
5035 | if (owner) { |
5036 | /* | |
5037 | * Since delayed_put_task_struct() also drops the last | |
5038 | * task reference we can safely take a new reference | |
5039 | * while holding the rcu_read_lock(). | |
5040 | */ | |
5041 | get_task_struct(owner); | |
5042 | } | |
5043 | rcu_read_unlock(); | |
5044 | ||
5045 | if (owner) { | |
f63a8daa PZ |
5046 | /* |
5047 | * If we're here through perf_event_exit_task() we're already | |
5048 | * holding ctx->mutex which would be an inversion wrt. the | |
5049 | * normal lock order. | |
5050 | * | |
5051 | * However we can safely take this lock because its the child | |
5052 | * ctx->mutex. | |
5053 | */ | |
5054 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
5055 | ||
8882135b PZ |
5056 | /* |
5057 | * We have to re-check the event->owner field, if it is cleared | |
5058 | * we raced with perf_event_exit_task(), acquiring the mutex | |
5059 | * ensured they're done, and we can proceed with freeing the | |
5060 | * event. | |
5061 | */ | |
f47c02c0 | 5062 | if (event->owner) { |
8882135b | 5063 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
5064 | smp_store_release(&event->owner, NULL); |
5065 | } | |
8882135b PZ |
5066 | mutex_unlock(&owner->perf_event_mutex); |
5067 | put_task_struct(owner); | |
5068 | } | |
f8697762 JO |
5069 | } |
5070 | ||
f8697762 JO |
5071 | static void put_event(struct perf_event *event) |
5072 | { | |
f8697762 JO |
5073 | if (!atomic_long_dec_and_test(&event->refcount)) |
5074 | return; | |
5075 | ||
c6e5b732 PZ |
5076 | _free_event(event); |
5077 | } | |
5078 | ||
5079 | /* | |
5080 | * Kill an event dead; while event:refcount will preserve the event | |
5081 | * object, it will not preserve its functionality. Once the last 'user' | |
5082 | * gives up the object, we'll destroy the thing. | |
5083 | */ | |
5084 | int perf_event_release_kernel(struct perf_event *event) | |
5085 | { | |
a4f4bb6d | 5086 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 5087 | struct perf_event *child, *tmp; |
82d94856 | 5088 | LIST_HEAD(free_list); |
c6e5b732 | 5089 | |
a4f4bb6d PZ |
5090 | /* |
5091 | * If we got here through err_file: fput(event_file); we will not have | |
5092 | * attached to a context yet. | |
5093 | */ | |
5094 | if (!ctx) { | |
5095 | WARN_ON_ONCE(event->attach_state & | |
5096 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
5097 | goto no_ctx; | |
5098 | } | |
5099 | ||
f8697762 JO |
5100 | if (!is_kernel_event(event)) |
5101 | perf_remove_from_owner(event); | |
8882135b | 5102 | |
5fa7c8ec | 5103 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 5104 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 5105 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 5106 | |
a69b0ca4 | 5107 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 5108 | /* |
d8a8cfc7 | 5109 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 5110 | * anymore. |
683ede43 | 5111 | * |
a69b0ca4 PZ |
5112 | * Anybody acquiring event->child_mutex after the below loop _must_ |
5113 | * also see this, most importantly inherit_event() which will avoid | |
5114 | * placing more children on the list. | |
683ede43 | 5115 | * |
c6e5b732 PZ |
5116 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
5117 | * child events. | |
683ede43 | 5118 | */ |
a69b0ca4 PZ |
5119 | event->state = PERF_EVENT_STATE_DEAD; |
5120 | raw_spin_unlock_irq(&ctx->lock); | |
5121 | ||
5122 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 5123 | |
c6e5b732 PZ |
5124 | again: |
5125 | mutex_lock(&event->child_mutex); | |
5126 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 5127 | |
c6e5b732 PZ |
5128 | /* |
5129 | * Cannot change, child events are not migrated, see the | |
5130 | * comment with perf_event_ctx_lock_nested(). | |
5131 | */ | |
506458ef | 5132 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
5133 | /* |
5134 | * Since child_mutex nests inside ctx::mutex, we must jump | |
5135 | * through hoops. We start by grabbing a reference on the ctx. | |
5136 | * | |
5137 | * Since the event cannot get freed while we hold the | |
5138 | * child_mutex, the context must also exist and have a !0 | |
5139 | * reference count. | |
5140 | */ | |
5141 | get_ctx(ctx); | |
5142 | ||
5143 | /* | |
5144 | * Now that we have a ctx ref, we can drop child_mutex, and | |
5145 | * acquire ctx::mutex without fear of it going away. Then we | |
5146 | * can re-acquire child_mutex. | |
5147 | */ | |
5148 | mutex_unlock(&event->child_mutex); | |
5149 | mutex_lock(&ctx->mutex); | |
5150 | mutex_lock(&event->child_mutex); | |
5151 | ||
5152 | /* | |
5153 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
5154 | * state, if child is still the first entry, it didn't get freed | |
5155 | * and we can continue doing so. | |
5156 | */ | |
5157 | tmp = list_first_entry_or_null(&event->child_list, | |
5158 | struct perf_event, child_list); | |
5159 | if (tmp == child) { | |
5160 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 5161 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
5162 | /* |
5163 | * This matches the refcount bump in inherit_event(); | |
5164 | * this can't be the last reference. | |
5165 | */ | |
5166 | put_event(event); | |
5167 | } | |
5168 | ||
5169 | mutex_unlock(&event->child_mutex); | |
5170 | mutex_unlock(&ctx->mutex); | |
5171 | put_ctx(ctx); | |
5172 | goto again; | |
5173 | } | |
5174 | mutex_unlock(&event->child_mutex); | |
5175 | ||
82d94856 | 5176 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
5177 | void *var = &child->ctx->refcount; |
5178 | ||
82d94856 PZ |
5179 | list_del(&child->child_list); |
5180 | free_event(child); | |
1cf8dfe8 PZ |
5181 | |
5182 | /* | |
5183 | * Wake any perf_event_free_task() waiting for this event to be | |
5184 | * freed. | |
5185 | */ | |
5186 | smp_mb(); /* pairs with wait_var_event() */ | |
5187 | wake_up_var(var); | |
82d94856 PZ |
5188 | } |
5189 | ||
a4f4bb6d PZ |
5190 | no_ctx: |
5191 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
5192 | return 0; |
5193 | } | |
5194 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
5195 | ||
8b10c5e2 PZ |
5196 | /* |
5197 | * Called when the last reference to the file is gone. | |
5198 | */ | |
a6fa941d AV |
5199 | static int perf_release(struct inode *inode, struct file *file) |
5200 | { | |
c6e5b732 | 5201 | perf_event_release_kernel(file->private_data); |
a6fa941d | 5202 | return 0; |
fb0459d7 | 5203 | } |
fb0459d7 | 5204 | |
ca0dd44c | 5205 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 5206 | { |
cdd6c482 | 5207 | struct perf_event *child; |
e53c0994 PZ |
5208 | u64 total = 0; |
5209 | ||
59ed446f PZ |
5210 | *enabled = 0; |
5211 | *running = 0; | |
5212 | ||
6f10581a | 5213 | mutex_lock(&event->child_mutex); |
01add3ea | 5214 | |
7d88962e | 5215 | (void)perf_event_read(event, false); |
01add3ea SB |
5216 | total += perf_event_count(event); |
5217 | ||
59ed446f PZ |
5218 | *enabled += event->total_time_enabled + |
5219 | atomic64_read(&event->child_total_time_enabled); | |
5220 | *running += event->total_time_running + | |
5221 | atomic64_read(&event->child_total_time_running); | |
5222 | ||
5223 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5224 | (void)perf_event_read(child, false); |
01add3ea | 5225 | total += perf_event_count(child); |
59ed446f PZ |
5226 | *enabled += child->total_time_enabled; |
5227 | *running += child->total_time_running; | |
5228 | } | |
6f10581a | 5229 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5230 | |
5231 | return total; | |
5232 | } | |
ca0dd44c PZ |
5233 | |
5234 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5235 | { | |
5236 | struct perf_event_context *ctx; | |
5237 | u64 count; | |
5238 | ||
5239 | ctx = perf_event_ctx_lock(event); | |
5240 | count = __perf_event_read_value(event, enabled, running); | |
5241 | perf_event_ctx_unlock(event, ctx); | |
5242 | ||
5243 | return count; | |
5244 | } | |
fb0459d7 | 5245 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5246 | |
7d88962e | 5247 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5248 | u64 read_format, u64 *values) |
3dab77fb | 5249 | { |
2aeb1883 | 5250 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5251 | struct perf_event *sub; |
2aeb1883 | 5252 | unsigned long flags; |
fa8c2693 | 5253 | int n = 1; /* skip @nr */ |
7d88962e | 5254 | int ret; |
f63a8daa | 5255 | |
7d88962e SB |
5256 | ret = perf_event_read(leader, true); |
5257 | if (ret) | |
5258 | return ret; | |
abf4868b | 5259 | |
a9cd8194 PZ |
5260 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5261 | ||
fa8c2693 PZ |
5262 | /* |
5263 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5264 | * will be identical to those of the leader, so we only publish one | |
5265 | * set. | |
5266 | */ | |
5267 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5268 | values[n++] += leader->total_time_enabled + | |
5269 | atomic64_read(&leader->child_total_time_enabled); | |
5270 | } | |
3dab77fb | 5271 | |
fa8c2693 PZ |
5272 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5273 | values[n++] += leader->total_time_running + | |
5274 | atomic64_read(&leader->child_total_time_running); | |
5275 | } | |
5276 | ||
5277 | /* | |
5278 | * Write {count,id} tuples for every sibling. | |
5279 | */ | |
5280 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5281 | if (read_format & PERF_FORMAT_ID) |
5282 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5283 | |
edb39592 | 5284 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5285 | values[n++] += perf_event_count(sub); |
5286 | if (read_format & PERF_FORMAT_ID) | |
5287 | values[n++] = primary_event_id(sub); | |
5288 | } | |
7d88962e | 5289 | |
2aeb1883 | 5290 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5291 | return 0; |
fa8c2693 | 5292 | } |
3dab77fb | 5293 | |
fa8c2693 PZ |
5294 | static int perf_read_group(struct perf_event *event, |
5295 | u64 read_format, char __user *buf) | |
5296 | { | |
5297 | struct perf_event *leader = event->group_leader, *child; | |
5298 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5299 | int ret; |
fa8c2693 | 5300 | u64 *values; |
3dab77fb | 5301 | |
fa8c2693 | 5302 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5303 | |
fa8c2693 PZ |
5304 | values = kzalloc(event->read_size, GFP_KERNEL); |
5305 | if (!values) | |
5306 | return -ENOMEM; | |
3dab77fb | 5307 | |
fa8c2693 PZ |
5308 | values[0] = 1 + leader->nr_siblings; |
5309 | ||
5310 | /* | |
5311 | * By locking the child_mutex of the leader we effectively | |
5312 | * lock the child list of all siblings.. XXX explain how. | |
5313 | */ | |
5314 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5315 | |
7d88962e SB |
5316 | ret = __perf_read_group_add(leader, read_format, values); |
5317 | if (ret) | |
5318 | goto unlock; | |
5319 | ||
5320 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5321 | ret = __perf_read_group_add(child, read_format, values); | |
5322 | if (ret) | |
5323 | goto unlock; | |
5324 | } | |
abf4868b | 5325 | |
fa8c2693 | 5326 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5327 | |
7d88962e | 5328 | ret = event->read_size; |
fa8c2693 PZ |
5329 | if (copy_to_user(buf, values, event->read_size)) |
5330 | ret = -EFAULT; | |
7d88962e | 5331 | goto out; |
fa8c2693 | 5332 | |
7d88962e SB |
5333 | unlock: |
5334 | mutex_unlock(&leader->child_mutex); | |
5335 | out: | |
fa8c2693 | 5336 | kfree(values); |
abf4868b | 5337 | return ret; |
3dab77fb PZ |
5338 | } |
5339 | ||
b15f495b | 5340 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5341 | u64 read_format, char __user *buf) |
5342 | { | |
59ed446f | 5343 | u64 enabled, running; |
3dab77fb PZ |
5344 | u64 values[4]; |
5345 | int n = 0; | |
5346 | ||
ca0dd44c | 5347 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5348 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5349 | values[n++] = enabled; | |
5350 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5351 | values[n++] = running; | |
3dab77fb | 5352 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5353 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5354 | |
5355 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5356 | return -EFAULT; | |
5357 | ||
5358 | return n * sizeof(u64); | |
5359 | } | |
5360 | ||
dc633982 JO |
5361 | static bool is_event_hup(struct perf_event *event) |
5362 | { | |
5363 | bool no_children; | |
5364 | ||
a69b0ca4 | 5365 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5366 | return false; |
5367 | ||
5368 | mutex_lock(&event->child_mutex); | |
5369 | no_children = list_empty(&event->child_list); | |
5370 | mutex_unlock(&event->child_mutex); | |
5371 | return no_children; | |
5372 | } | |
5373 | ||
0793a61d | 5374 | /* |
cdd6c482 | 5375 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5376 | */ |
5377 | static ssize_t | |
b15f495b | 5378 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5379 | { |
cdd6c482 | 5380 | u64 read_format = event->attr.read_format; |
3dab77fb | 5381 | int ret; |
0793a61d | 5382 | |
3b6f9e5c | 5383 | /* |
788faab7 | 5384 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5385 | * error state (i.e. because it was pinned but it couldn't be |
5386 | * scheduled on to the CPU at some point). | |
5387 | */ | |
cdd6c482 | 5388 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5389 | return 0; |
5390 | ||
c320c7b7 | 5391 | if (count < event->read_size) |
3dab77fb PZ |
5392 | return -ENOSPC; |
5393 | ||
cdd6c482 | 5394 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5395 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5396 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5397 | else |
b15f495b | 5398 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5399 | |
3dab77fb | 5400 | return ret; |
0793a61d TG |
5401 | } |
5402 | ||
0793a61d TG |
5403 | static ssize_t |
5404 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5405 | { | |
cdd6c482 | 5406 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5407 | struct perf_event_context *ctx; |
5408 | int ret; | |
0793a61d | 5409 | |
da97e184 JFG |
5410 | ret = security_perf_event_read(event); |
5411 | if (ret) | |
5412 | return ret; | |
5413 | ||
f63a8daa | 5414 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5415 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5416 | perf_event_ctx_unlock(event, ctx); |
5417 | ||
5418 | return ret; | |
0793a61d TG |
5419 | } |
5420 | ||
9dd95748 | 5421 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5422 | { |
cdd6c482 | 5423 | struct perf_event *event = file->private_data; |
56de4e8f | 5424 | struct perf_buffer *rb; |
a9a08845 | 5425 | __poll_t events = EPOLLHUP; |
c7138f37 | 5426 | |
e708d7ad | 5427 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5428 | |
dc633982 | 5429 | if (is_event_hup(event)) |
179033b3 | 5430 | return events; |
c7138f37 | 5431 | |
10c6db11 | 5432 | /* |
9bb5d40c PZ |
5433 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5434 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5435 | */ |
5436 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5437 | rb = event->rb; |
5438 | if (rb) | |
76369139 | 5439 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5440 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5441 | return events; |
5442 | } | |
5443 | ||
f63a8daa | 5444 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5445 | { |
7d88962e | 5446 | (void)perf_event_read(event, false); |
e7850595 | 5447 | local64_set(&event->count, 0); |
cdd6c482 | 5448 | perf_event_update_userpage(event); |
3df5edad PZ |
5449 | } |
5450 | ||
52ba4b0b LX |
5451 | /* Assume it's not an event with inherit set. */ |
5452 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5453 | { | |
5454 | struct perf_event_context *ctx; | |
5455 | u64 count; | |
5456 | ||
5457 | ctx = perf_event_ctx_lock(event); | |
5458 | WARN_ON_ONCE(event->attr.inherit); | |
5459 | _perf_event_disable(event); | |
5460 | count = local64_read(&event->count); | |
5461 | if (reset) | |
5462 | local64_set(&event->count, 0); | |
5463 | perf_event_ctx_unlock(event, ctx); | |
5464 | ||
5465 | return count; | |
5466 | } | |
5467 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5468 | ||
c93f7669 | 5469 | /* |
cdd6c482 IM |
5470 | * Holding the top-level event's child_mutex means that any |
5471 | * descendant process that has inherited this event will block | |
8ba289b8 | 5472 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5473 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5474 | */ |
cdd6c482 IM |
5475 | static void perf_event_for_each_child(struct perf_event *event, |
5476 | void (*func)(struct perf_event *)) | |
3df5edad | 5477 | { |
cdd6c482 | 5478 | struct perf_event *child; |
3df5edad | 5479 | |
cdd6c482 | 5480 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5481 | |
cdd6c482 IM |
5482 | mutex_lock(&event->child_mutex); |
5483 | func(event); | |
5484 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5485 | func(child); |
cdd6c482 | 5486 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5487 | } |
5488 | ||
cdd6c482 IM |
5489 | static void perf_event_for_each(struct perf_event *event, |
5490 | void (*func)(struct perf_event *)) | |
3df5edad | 5491 | { |
cdd6c482 IM |
5492 | struct perf_event_context *ctx = event->ctx; |
5493 | struct perf_event *sibling; | |
3df5edad | 5494 | |
f63a8daa PZ |
5495 | lockdep_assert_held(&ctx->mutex); |
5496 | ||
cdd6c482 | 5497 | event = event->group_leader; |
75f937f2 | 5498 | |
cdd6c482 | 5499 | perf_event_for_each_child(event, func); |
edb39592 | 5500 | for_each_sibling_event(sibling, event) |
724b6daa | 5501 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5502 | } |
5503 | ||
fae3fde6 PZ |
5504 | static void __perf_event_period(struct perf_event *event, |
5505 | struct perf_cpu_context *cpuctx, | |
5506 | struct perf_event_context *ctx, | |
5507 | void *info) | |
c7999c6f | 5508 | { |
fae3fde6 | 5509 | u64 value = *((u64 *)info); |
c7999c6f | 5510 | bool active; |
08247e31 | 5511 | |
cdd6c482 | 5512 | if (event->attr.freq) { |
cdd6c482 | 5513 | event->attr.sample_freq = value; |
08247e31 | 5514 | } else { |
cdd6c482 IM |
5515 | event->attr.sample_period = value; |
5516 | event->hw.sample_period = value; | |
08247e31 | 5517 | } |
bad7192b PZ |
5518 | |
5519 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5520 | if (active) { | |
5521 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5522 | /* |
5523 | * We could be throttled; unthrottle now to avoid the tick | |
5524 | * trying to unthrottle while we already re-started the event. | |
5525 | */ | |
5526 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5527 | event->hw.interrupts = 0; | |
5528 | perf_log_throttle(event, 1); | |
5529 | } | |
bad7192b PZ |
5530 | event->pmu->stop(event, PERF_EF_UPDATE); |
5531 | } | |
5532 | ||
5533 | local64_set(&event->hw.period_left, 0); | |
5534 | ||
5535 | if (active) { | |
5536 | event->pmu->start(event, PERF_EF_RELOAD); | |
5537 | perf_pmu_enable(ctx->pmu); | |
5538 | } | |
c7999c6f PZ |
5539 | } |
5540 | ||
81ec3f3c JO |
5541 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5542 | { | |
5543 | return event->pmu->check_period(event, value); | |
5544 | } | |
5545 | ||
3ca270fc | 5546 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5547 | { |
c7999c6f PZ |
5548 | if (!is_sampling_event(event)) |
5549 | return -EINVAL; | |
5550 | ||
c7999c6f PZ |
5551 | if (!value) |
5552 | return -EINVAL; | |
5553 | ||
5554 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5555 | return -EINVAL; | |
5556 | ||
81ec3f3c JO |
5557 | if (perf_event_check_period(event, value)) |
5558 | return -EINVAL; | |
5559 | ||
913a90bc RB |
5560 | if (!event->attr.freq && (value & (1ULL << 63))) |
5561 | return -EINVAL; | |
5562 | ||
fae3fde6 | 5563 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5564 | |
c7999c6f | 5565 | return 0; |
08247e31 PZ |
5566 | } |
5567 | ||
3ca270fc LX |
5568 | int perf_event_period(struct perf_event *event, u64 value) |
5569 | { | |
5570 | struct perf_event_context *ctx; | |
5571 | int ret; | |
5572 | ||
5573 | ctx = perf_event_ctx_lock(event); | |
5574 | ret = _perf_event_period(event, value); | |
5575 | perf_event_ctx_unlock(event, ctx); | |
5576 | ||
5577 | return ret; | |
5578 | } | |
5579 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5580 | ||
ac9721f3 PZ |
5581 | static const struct file_operations perf_fops; |
5582 | ||
2903ff01 | 5583 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5584 | { |
2903ff01 AV |
5585 | struct fd f = fdget(fd); |
5586 | if (!f.file) | |
5587 | return -EBADF; | |
ac9721f3 | 5588 | |
2903ff01 AV |
5589 | if (f.file->f_op != &perf_fops) { |
5590 | fdput(f); | |
5591 | return -EBADF; | |
ac9721f3 | 5592 | } |
2903ff01 AV |
5593 | *p = f; |
5594 | return 0; | |
ac9721f3 PZ |
5595 | } |
5596 | ||
5597 | static int perf_event_set_output(struct perf_event *event, | |
5598 | struct perf_event *output_event); | |
6fb2915d | 5599 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
32ff77e8 MC |
5600 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5601 | struct perf_event_attr *attr); | |
a4be7c27 | 5602 | |
f63a8daa | 5603 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5604 | { |
cdd6c482 | 5605 | void (*func)(struct perf_event *); |
3df5edad | 5606 | u32 flags = arg; |
d859e29f PM |
5607 | |
5608 | switch (cmd) { | |
cdd6c482 | 5609 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5610 | func = _perf_event_enable; |
d859e29f | 5611 | break; |
cdd6c482 | 5612 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5613 | func = _perf_event_disable; |
79f14641 | 5614 | break; |
cdd6c482 | 5615 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5616 | func = _perf_event_reset; |
6de6a7b9 | 5617 | break; |
3df5edad | 5618 | |
cdd6c482 | 5619 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5620 | return _perf_event_refresh(event, arg); |
08247e31 | 5621 | |
cdd6c482 | 5622 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5623 | { |
5624 | u64 value; | |
08247e31 | 5625 | |
3ca270fc LX |
5626 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5627 | return -EFAULT; | |
08247e31 | 5628 | |
3ca270fc LX |
5629 | return _perf_event_period(event, value); |
5630 | } | |
cf4957f1 JO |
5631 | case PERF_EVENT_IOC_ID: |
5632 | { | |
5633 | u64 id = primary_event_id(event); | |
5634 | ||
5635 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5636 | return -EFAULT; | |
5637 | return 0; | |
5638 | } | |
5639 | ||
cdd6c482 | 5640 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5641 | { |
ac9721f3 | 5642 | int ret; |
ac9721f3 | 5643 | if (arg != -1) { |
2903ff01 AV |
5644 | struct perf_event *output_event; |
5645 | struct fd output; | |
5646 | ret = perf_fget_light(arg, &output); | |
5647 | if (ret) | |
5648 | return ret; | |
5649 | output_event = output.file->private_data; | |
5650 | ret = perf_event_set_output(event, output_event); | |
5651 | fdput(output); | |
5652 | } else { | |
5653 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5654 | } |
ac9721f3 PZ |
5655 | return ret; |
5656 | } | |
a4be7c27 | 5657 | |
6fb2915d LZ |
5658 | case PERF_EVENT_IOC_SET_FILTER: |
5659 | return perf_event_set_filter(event, (void __user *)arg); | |
5660 | ||
2541517c | 5661 | case PERF_EVENT_IOC_SET_BPF: |
652c1b17 AN |
5662 | { |
5663 | struct bpf_prog *prog; | |
5664 | int err; | |
5665 | ||
5666 | prog = bpf_prog_get(arg); | |
5667 | if (IS_ERR(prog)) | |
5668 | return PTR_ERR(prog); | |
5669 | ||
82e6b1ee | 5670 | err = perf_event_set_bpf_prog(event, prog, 0); |
652c1b17 AN |
5671 | if (err) { |
5672 | bpf_prog_put(prog); | |
5673 | return err; | |
5674 | } | |
5675 | ||
5676 | return 0; | |
5677 | } | |
2541517c | 5678 | |
86e7972f | 5679 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5680 | struct perf_buffer *rb; |
86e7972f WN |
5681 | |
5682 | rcu_read_lock(); | |
5683 | rb = rcu_dereference(event->rb); | |
5684 | if (!rb || !rb->nr_pages) { | |
5685 | rcu_read_unlock(); | |
5686 | return -EINVAL; | |
5687 | } | |
5688 | rb_toggle_paused(rb, !!arg); | |
5689 | rcu_read_unlock(); | |
5690 | return 0; | |
5691 | } | |
f371b304 YS |
5692 | |
5693 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5694 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5695 | |
5696 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5697 | struct perf_event_attr new_attr; | |
5698 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5699 | &new_attr); | |
5700 | ||
5701 | if (err) | |
5702 | return err; | |
5703 | ||
5704 | return perf_event_modify_attr(event, &new_attr); | |
5705 | } | |
d859e29f | 5706 | default: |
3df5edad | 5707 | return -ENOTTY; |
d859e29f | 5708 | } |
3df5edad PZ |
5709 | |
5710 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5711 | perf_event_for_each(event, func); |
3df5edad | 5712 | else |
cdd6c482 | 5713 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5714 | |
5715 | return 0; | |
d859e29f PM |
5716 | } |
5717 | ||
f63a8daa PZ |
5718 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5719 | { | |
5720 | struct perf_event *event = file->private_data; | |
5721 | struct perf_event_context *ctx; | |
5722 | long ret; | |
5723 | ||
da97e184 JFG |
5724 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5725 | ret = security_perf_event_write(event); | |
5726 | if (ret) | |
5727 | return ret; | |
5728 | ||
f63a8daa PZ |
5729 | ctx = perf_event_ctx_lock(event); |
5730 | ret = _perf_ioctl(event, cmd, arg); | |
5731 | perf_event_ctx_unlock(event, ctx); | |
5732 | ||
5733 | return ret; | |
5734 | } | |
5735 | ||
b3f20785 PM |
5736 | #ifdef CONFIG_COMPAT |
5737 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5738 | unsigned long arg) | |
5739 | { | |
5740 | switch (_IOC_NR(cmd)) { | |
5741 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5742 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5743 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5744 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5745 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5746 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5747 | cmd &= ~IOCSIZE_MASK; | |
5748 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5749 | } | |
5750 | break; | |
5751 | } | |
5752 | return perf_ioctl(file, cmd, arg); | |
5753 | } | |
5754 | #else | |
5755 | # define perf_compat_ioctl NULL | |
5756 | #endif | |
5757 | ||
cdd6c482 | 5758 | int perf_event_task_enable(void) |
771d7cde | 5759 | { |
f63a8daa | 5760 | struct perf_event_context *ctx; |
cdd6c482 | 5761 | struct perf_event *event; |
771d7cde | 5762 | |
cdd6c482 | 5763 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5764 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5765 | ctx = perf_event_ctx_lock(event); | |
5766 | perf_event_for_each_child(event, _perf_event_enable); | |
5767 | perf_event_ctx_unlock(event, ctx); | |
5768 | } | |
cdd6c482 | 5769 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5770 | |
5771 | return 0; | |
5772 | } | |
5773 | ||
cdd6c482 | 5774 | int perf_event_task_disable(void) |
771d7cde | 5775 | { |
f63a8daa | 5776 | struct perf_event_context *ctx; |
cdd6c482 | 5777 | struct perf_event *event; |
771d7cde | 5778 | |
cdd6c482 | 5779 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5780 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5781 | ctx = perf_event_ctx_lock(event); | |
5782 | perf_event_for_each_child(event, _perf_event_disable); | |
5783 | perf_event_ctx_unlock(event, ctx); | |
5784 | } | |
cdd6c482 | 5785 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5786 | |
5787 | return 0; | |
5788 | } | |
5789 | ||
cdd6c482 | 5790 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5791 | { |
a4eaf7f1 PZ |
5792 | if (event->hw.state & PERF_HES_STOPPED) |
5793 | return 0; | |
5794 | ||
cdd6c482 | 5795 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5796 | return 0; |
5797 | ||
35edc2a5 | 5798 | return event->pmu->event_idx(event); |
194002b2 PZ |
5799 | } |
5800 | ||
c4794295 | 5801 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5802 | u64 *now, |
7f310a5d EM |
5803 | u64 *enabled, |
5804 | u64 *running) | |
c4794295 | 5805 | { |
e3f3541c | 5806 | u64 ctx_time; |
c4794295 | 5807 | |
e3f3541c PZ |
5808 | *now = perf_clock(); |
5809 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5810 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5811 | } |
5812 | ||
fa731587 PZ |
5813 | static void perf_event_init_userpage(struct perf_event *event) |
5814 | { | |
5815 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5816 | struct perf_buffer *rb; |
fa731587 PZ |
5817 | |
5818 | rcu_read_lock(); | |
5819 | rb = rcu_dereference(event->rb); | |
5820 | if (!rb) | |
5821 | goto unlock; | |
5822 | ||
5823 | userpg = rb->user_page; | |
5824 | ||
5825 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5826 | userpg->cap_bit0_is_deprecated = 1; | |
5827 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5828 | userpg->data_offset = PAGE_SIZE; |
5829 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5830 | |
5831 | unlock: | |
5832 | rcu_read_unlock(); | |
5833 | } | |
5834 | ||
c1317ec2 AL |
5835 | void __weak arch_perf_update_userpage( |
5836 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5837 | { |
5838 | } | |
5839 | ||
38ff667b PZ |
5840 | /* |
5841 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5842 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5843 | * code calls this from NMI context. | |
5844 | */ | |
cdd6c482 | 5845 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5846 | { |
cdd6c482 | 5847 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5848 | struct perf_buffer *rb; |
e3f3541c | 5849 | u64 enabled, running, now; |
38ff667b PZ |
5850 | |
5851 | rcu_read_lock(); | |
5ec4c599 PZ |
5852 | rb = rcu_dereference(event->rb); |
5853 | if (!rb) | |
5854 | goto unlock; | |
5855 | ||
0d641208 EM |
5856 | /* |
5857 | * compute total_time_enabled, total_time_running | |
5858 | * based on snapshot values taken when the event | |
5859 | * was last scheduled in. | |
5860 | * | |
5861 | * we cannot simply called update_context_time() | |
5862 | * because of locking issue as we can be called in | |
5863 | * NMI context | |
5864 | */ | |
e3f3541c | 5865 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5866 | |
76369139 | 5867 | userpg = rb->user_page; |
7b732a75 | 5868 | /* |
9d2dcc8f MF |
5869 | * Disable preemption to guarantee consistent time stamps are stored to |
5870 | * the user page. | |
7b732a75 PZ |
5871 | */ |
5872 | preempt_disable(); | |
37d81828 | 5873 | ++userpg->lock; |
92f22a38 | 5874 | barrier(); |
cdd6c482 | 5875 | userpg->index = perf_event_index(event); |
b5e58793 | 5876 | userpg->offset = perf_event_count(event); |
365a4038 | 5877 | if (userpg->index) |
e7850595 | 5878 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5879 | |
0d641208 | 5880 | userpg->time_enabled = enabled + |
cdd6c482 | 5881 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5882 | |
0d641208 | 5883 | userpg->time_running = running + |
cdd6c482 | 5884 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5885 | |
c1317ec2 | 5886 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5887 | |
92f22a38 | 5888 | barrier(); |
37d81828 | 5889 | ++userpg->lock; |
7b732a75 | 5890 | preempt_enable(); |
38ff667b | 5891 | unlock: |
7b732a75 | 5892 | rcu_read_unlock(); |
37d81828 | 5893 | } |
82975c46 | 5894 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5895 | |
9e3ed2d7 | 5896 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5897 | { |
11bac800 | 5898 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5899 | struct perf_buffer *rb; |
9e3ed2d7 | 5900 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5901 | |
5902 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5903 | if (vmf->pgoff == 0) | |
5904 | ret = 0; | |
5905 | return ret; | |
5906 | } | |
5907 | ||
5908 | rcu_read_lock(); | |
76369139 FW |
5909 | rb = rcu_dereference(event->rb); |
5910 | if (!rb) | |
906010b2 PZ |
5911 | goto unlock; |
5912 | ||
5913 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5914 | goto unlock; | |
5915 | ||
76369139 | 5916 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5917 | if (!vmf->page) |
5918 | goto unlock; | |
5919 | ||
5920 | get_page(vmf->page); | |
11bac800 | 5921 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5922 | vmf->page->index = vmf->pgoff; |
5923 | ||
5924 | ret = 0; | |
5925 | unlock: | |
5926 | rcu_read_unlock(); | |
5927 | ||
5928 | return ret; | |
5929 | } | |
5930 | ||
10c6db11 | 5931 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5932 | struct perf_buffer *rb) |
10c6db11 | 5933 | { |
56de4e8f | 5934 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5935 | unsigned long flags; |
5936 | ||
b69cf536 PZ |
5937 | if (event->rb) { |
5938 | /* | |
5939 | * Should be impossible, we set this when removing | |
5940 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5941 | */ | |
5942 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5943 | |
b69cf536 | 5944 | old_rb = event->rb; |
b69cf536 PZ |
5945 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5946 | list_del_rcu(&event->rb_entry); | |
5947 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5948 | |
2f993cf0 ON |
5949 | event->rcu_batches = get_state_synchronize_rcu(); |
5950 | event->rcu_pending = 1; | |
b69cf536 | 5951 | } |
10c6db11 | 5952 | |
b69cf536 | 5953 | if (rb) { |
2f993cf0 ON |
5954 | if (event->rcu_pending) { |
5955 | cond_synchronize_rcu(event->rcu_batches); | |
5956 | event->rcu_pending = 0; | |
5957 | } | |
5958 | ||
b69cf536 PZ |
5959 | spin_lock_irqsave(&rb->event_lock, flags); |
5960 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5961 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5962 | } | |
5963 | ||
767ae086 AS |
5964 | /* |
5965 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5966 | * before swizzling the event::rb pointer; if it's getting | |
5967 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5968 | * restart. See the comment in __perf_pmu_output_stop(). | |
5969 | * | |
5970 | * Data will inevitably be lost when set_output is done in | |
5971 | * mid-air, but then again, whoever does it like this is | |
5972 | * not in for the data anyway. | |
5973 | */ | |
5974 | if (has_aux(event)) | |
5975 | perf_event_stop(event, 0); | |
5976 | ||
b69cf536 PZ |
5977 | rcu_assign_pointer(event->rb, rb); |
5978 | ||
5979 | if (old_rb) { | |
5980 | ring_buffer_put(old_rb); | |
5981 | /* | |
5982 | * Since we detached before setting the new rb, so that we | |
5983 | * could attach the new rb, we could have missed a wakeup. | |
5984 | * Provide it now. | |
5985 | */ | |
5986 | wake_up_all(&event->waitq); | |
5987 | } | |
10c6db11 PZ |
5988 | } |
5989 | ||
5990 | static void ring_buffer_wakeup(struct perf_event *event) | |
5991 | { | |
56de4e8f | 5992 | struct perf_buffer *rb; |
10c6db11 PZ |
5993 | |
5994 | rcu_read_lock(); | |
5995 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5996 | if (rb) { |
5997 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5998 | wake_up_all(&event->waitq); | |
5999 | } | |
10c6db11 PZ |
6000 | rcu_read_unlock(); |
6001 | } | |
6002 | ||
56de4e8f | 6003 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 6004 | { |
56de4e8f | 6005 | struct perf_buffer *rb; |
7b732a75 | 6006 | |
ac9721f3 | 6007 | rcu_read_lock(); |
76369139 FW |
6008 | rb = rcu_dereference(event->rb); |
6009 | if (rb) { | |
fecb8ed2 | 6010 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 6011 | rb = NULL; |
ac9721f3 PZ |
6012 | } |
6013 | rcu_read_unlock(); | |
6014 | ||
76369139 | 6015 | return rb; |
ac9721f3 PZ |
6016 | } |
6017 | ||
56de4e8f | 6018 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 6019 | { |
fecb8ed2 | 6020 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 6021 | return; |
7b732a75 | 6022 | |
9bb5d40c | 6023 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 6024 | |
76369139 | 6025 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
6026 | } |
6027 | ||
6028 | static void perf_mmap_open(struct vm_area_struct *vma) | |
6029 | { | |
cdd6c482 | 6030 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 6031 | |
cdd6c482 | 6032 | atomic_inc(&event->mmap_count); |
9bb5d40c | 6033 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 6034 | |
45bfb2e5 PZ |
6035 | if (vma->vm_pgoff) |
6036 | atomic_inc(&event->rb->aux_mmap_count); | |
6037 | ||
1e0fb9ec | 6038 | if (event->pmu->event_mapped) |
bfe33492 | 6039 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
6040 | } |
6041 | ||
95ff4ca2 AS |
6042 | static void perf_pmu_output_stop(struct perf_event *event); |
6043 | ||
9bb5d40c PZ |
6044 | /* |
6045 | * A buffer can be mmap()ed multiple times; either directly through the same | |
6046 | * event, or through other events by use of perf_event_set_output(). | |
6047 | * | |
6048 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
6049 | * the buffer here, where we still have a VM context. This means we need | |
6050 | * to detach all events redirecting to us. | |
6051 | */ | |
7b732a75 PZ |
6052 | static void perf_mmap_close(struct vm_area_struct *vma) |
6053 | { | |
cdd6c482 | 6054 | struct perf_event *event = vma->vm_file->private_data; |
56de4e8f | 6055 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
6056 | struct user_struct *mmap_user = rb->mmap_user; |
6057 | int mmap_locked = rb->mmap_locked; | |
6058 | unsigned long size = perf_data_size(rb); | |
f91072ed | 6059 | bool detach_rest = false; |
789f90fc | 6060 | |
1e0fb9ec | 6061 | if (event->pmu->event_unmapped) |
bfe33492 | 6062 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 6063 | |
45bfb2e5 PZ |
6064 | /* |
6065 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
6066 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
6067 | * serialize with perf_mmap here. | |
6068 | */ | |
6069 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
6070 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
6071 | /* |
6072 | * Stop all AUX events that are writing to this buffer, | |
6073 | * so that we can free its AUX pages and corresponding PMU | |
6074 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
6075 | * they won't start any more (see perf_aux_output_begin()). | |
6076 | */ | |
6077 | perf_pmu_output_stop(event); | |
6078 | ||
6079 | /* now it's safe to free the pages */ | |
36b3db03 AS |
6080 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
6081 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 6082 | |
95ff4ca2 | 6083 | /* this has to be the last one */ |
45bfb2e5 | 6084 | rb_free_aux(rb); |
ca3bb3d0 | 6085 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 6086 | |
45bfb2e5 PZ |
6087 | mutex_unlock(&event->mmap_mutex); |
6088 | } | |
6089 | ||
f91072ed JO |
6090 | if (atomic_dec_and_test(&rb->mmap_count)) |
6091 | detach_rest = true; | |
9bb5d40c PZ |
6092 | |
6093 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 6094 | goto out_put; |
9bb5d40c | 6095 | |
b69cf536 | 6096 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
6097 | mutex_unlock(&event->mmap_mutex); |
6098 | ||
6099 | /* If there's still other mmap()s of this buffer, we're done. */ | |
f91072ed | 6100 | if (!detach_rest) |
b69cf536 | 6101 | goto out_put; |
ac9721f3 | 6102 | |
9bb5d40c PZ |
6103 | /* |
6104 | * No other mmap()s, detach from all other events that might redirect | |
6105 | * into the now unreachable buffer. Somewhat complicated by the | |
6106 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
6107 | */ | |
6108 | again: | |
6109 | rcu_read_lock(); | |
6110 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
6111 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
6112 | /* | |
6113 | * This event is en-route to free_event() which will | |
6114 | * detach it and remove it from the list. | |
6115 | */ | |
6116 | continue; | |
6117 | } | |
6118 | rcu_read_unlock(); | |
789f90fc | 6119 | |
9bb5d40c PZ |
6120 | mutex_lock(&event->mmap_mutex); |
6121 | /* | |
6122 | * Check we didn't race with perf_event_set_output() which can | |
6123 | * swizzle the rb from under us while we were waiting to | |
6124 | * acquire mmap_mutex. | |
6125 | * | |
6126 | * If we find a different rb; ignore this event, a next | |
6127 | * iteration will no longer find it on the list. We have to | |
6128 | * still restart the iteration to make sure we're not now | |
6129 | * iterating the wrong list. | |
6130 | */ | |
b69cf536 PZ |
6131 | if (event->rb == rb) |
6132 | ring_buffer_attach(event, NULL); | |
6133 | ||
cdd6c482 | 6134 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 6135 | put_event(event); |
ac9721f3 | 6136 | |
9bb5d40c PZ |
6137 | /* |
6138 | * Restart the iteration; either we're on the wrong list or | |
6139 | * destroyed its integrity by doing a deletion. | |
6140 | */ | |
6141 | goto again; | |
7b732a75 | 6142 | } |
9bb5d40c PZ |
6143 | rcu_read_unlock(); |
6144 | ||
6145 | /* | |
6146 | * It could be there's still a few 0-ref events on the list; they'll | |
6147 | * get cleaned up by free_event() -- they'll also still have their | |
6148 | * ref on the rb and will free it whenever they are done with it. | |
6149 | * | |
6150 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
6151 | * undo the VM accounting. | |
6152 | */ | |
6153 | ||
d44248a4 SL |
6154 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
6155 | &mmap_user->locked_vm); | |
70f8a3ca | 6156 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
6157 | free_uid(mmap_user); |
6158 | ||
b69cf536 | 6159 | out_put: |
9bb5d40c | 6160 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
6161 | } |
6162 | ||
f0f37e2f | 6163 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 6164 | .open = perf_mmap_open, |
fca0c116 | 6165 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
6166 | .fault = perf_mmap_fault, |
6167 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
6168 | }; |
6169 | ||
6170 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
6171 | { | |
cdd6c482 | 6172 | struct perf_event *event = file->private_data; |
22a4f650 | 6173 | unsigned long user_locked, user_lock_limit; |
789f90fc | 6174 | struct user_struct *user = current_user(); |
56de4e8f | 6175 | struct perf_buffer *rb = NULL; |
22a4f650 | 6176 | unsigned long locked, lock_limit; |
7b732a75 PZ |
6177 | unsigned long vma_size; |
6178 | unsigned long nr_pages; | |
45bfb2e5 | 6179 | long user_extra = 0, extra = 0; |
d57e34fd | 6180 | int ret = 0, flags = 0; |
37d81828 | 6181 | |
c7920614 PZ |
6182 | /* |
6183 | * Don't allow mmap() of inherited per-task counters. This would | |
6184 | * create a performance issue due to all children writing to the | |
76369139 | 6185 | * same rb. |
c7920614 PZ |
6186 | */ |
6187 | if (event->cpu == -1 && event->attr.inherit) | |
6188 | return -EINVAL; | |
6189 | ||
43a21ea8 | 6190 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 6191 | return -EINVAL; |
7b732a75 | 6192 | |
da97e184 JFG |
6193 | ret = security_perf_event_read(event); |
6194 | if (ret) | |
6195 | return ret; | |
6196 | ||
7b732a75 | 6197 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
6198 | |
6199 | if (vma->vm_pgoff == 0) { | |
6200 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
6201 | } else { | |
6202 | /* | |
6203 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
6204 | * mapped, all subsequent mappings should have the same size | |
6205 | * and offset. Must be above the normal perf buffer. | |
6206 | */ | |
6207 | u64 aux_offset, aux_size; | |
6208 | ||
6209 | if (!event->rb) | |
6210 | return -EINVAL; | |
6211 | ||
6212 | nr_pages = vma_size / PAGE_SIZE; | |
6213 | ||
6214 | mutex_lock(&event->mmap_mutex); | |
6215 | ret = -EINVAL; | |
6216 | ||
6217 | rb = event->rb; | |
6218 | if (!rb) | |
6219 | goto aux_unlock; | |
6220 | ||
6aa7de05 MR |
6221 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
6222 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6223 | |
6224 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6225 | goto aux_unlock; | |
6226 | ||
6227 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6228 | goto aux_unlock; | |
6229 | ||
6230 | /* already mapped with a different offset */ | |
6231 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6232 | goto aux_unlock; | |
6233 | ||
6234 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6235 | goto aux_unlock; | |
6236 | ||
6237 | /* already mapped with a different size */ | |
6238 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6239 | goto aux_unlock; | |
6240 | ||
6241 | if (!is_power_of_2(nr_pages)) | |
6242 | goto aux_unlock; | |
6243 | ||
6244 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6245 | goto aux_unlock; | |
6246 | ||
6247 | if (rb_has_aux(rb)) { | |
6248 | atomic_inc(&rb->aux_mmap_count); | |
6249 | ret = 0; | |
6250 | goto unlock; | |
6251 | } | |
6252 | ||
6253 | atomic_set(&rb->aux_mmap_count, 1); | |
6254 | user_extra = nr_pages; | |
6255 | ||
6256 | goto accounting; | |
6257 | } | |
7b732a75 | 6258 | |
7730d865 | 6259 | /* |
76369139 | 6260 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6261 | * can do bitmasks instead of modulo. |
6262 | */ | |
2ed11312 | 6263 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6264 | return -EINVAL; |
6265 | ||
7b732a75 | 6266 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6267 | return -EINVAL; |
6268 | ||
cdd6c482 | 6269 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6270 | again: |
cdd6c482 | 6271 | mutex_lock(&event->mmap_mutex); |
76369139 | 6272 | if (event->rb) { |
9bb5d40c | 6273 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6274 | ret = -EINVAL; |
9bb5d40c PZ |
6275 | goto unlock; |
6276 | } | |
6277 | ||
6278 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6279 | /* | |
6280 | * Raced against perf_mmap_close() through | |
6281 | * perf_event_set_output(). Try again, hope for better | |
6282 | * luck. | |
6283 | */ | |
6284 | mutex_unlock(&event->mmap_mutex); | |
6285 | goto again; | |
6286 | } | |
6287 | ||
ebb3c4c4 PZ |
6288 | goto unlock; |
6289 | } | |
6290 | ||
789f90fc | 6291 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6292 | |
6293 | accounting: | |
cdd6c482 | 6294 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6295 | |
6296 | /* | |
6297 | * Increase the limit linearly with more CPUs: | |
6298 | */ | |
6299 | user_lock_limit *= num_online_cpus(); | |
6300 | ||
00346155 SL |
6301 | user_locked = atomic_long_read(&user->locked_vm); |
6302 | ||
6303 | /* | |
6304 | * sysctl_perf_event_mlock may have changed, so that | |
6305 | * user->locked_vm > user_lock_limit | |
6306 | */ | |
6307 | if (user_locked > user_lock_limit) | |
6308 | user_locked = user_lock_limit; | |
6309 | user_locked += user_extra; | |
c5078f78 | 6310 | |
c4b75479 | 6311 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6312 | /* |
6313 | * charge locked_vm until it hits user_lock_limit; | |
6314 | * charge the rest from pinned_vm | |
6315 | */ | |
789f90fc | 6316 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6317 | user_extra -= extra; |
6318 | } | |
7b732a75 | 6319 | |
78d7d407 | 6320 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6321 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6322 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6323 | |
da97e184 | 6324 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6325 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6326 | ret = -EPERM; |
6327 | goto unlock; | |
6328 | } | |
7b732a75 | 6329 | |
45bfb2e5 | 6330 | WARN_ON(!rb && event->rb); |
906010b2 | 6331 | |
d57e34fd | 6332 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6333 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6334 | |
76369139 | 6335 | if (!rb) { |
45bfb2e5 PZ |
6336 | rb = rb_alloc(nr_pages, |
6337 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6338 | event->cpu, flags); | |
26cb63ad | 6339 | |
45bfb2e5 PZ |
6340 | if (!rb) { |
6341 | ret = -ENOMEM; | |
6342 | goto unlock; | |
6343 | } | |
43a21ea8 | 6344 | |
45bfb2e5 PZ |
6345 | atomic_set(&rb->mmap_count, 1); |
6346 | rb->mmap_user = get_current_user(); | |
6347 | rb->mmap_locked = extra; | |
26cb63ad | 6348 | |
45bfb2e5 | 6349 | ring_buffer_attach(event, rb); |
ac9721f3 | 6350 | |
f7925653 SL |
6351 | perf_event_update_time(event); |
6352 | perf_set_shadow_time(event, event->ctx); | |
45bfb2e5 PZ |
6353 | perf_event_init_userpage(event); |
6354 | perf_event_update_userpage(event); | |
6355 | } else { | |
1a594131 AS |
6356 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6357 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6358 | if (!ret) |
6359 | rb->aux_mmap_locked = extra; | |
6360 | } | |
9a0f05cb | 6361 | |
ebb3c4c4 | 6362 | unlock: |
45bfb2e5 PZ |
6363 | if (!ret) { |
6364 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6365 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6366 | |
ac9721f3 | 6367 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6368 | } else if (rb) { |
6369 | atomic_dec(&rb->mmap_count); | |
6370 | } | |
6371 | aux_unlock: | |
cdd6c482 | 6372 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6373 | |
9bb5d40c PZ |
6374 | /* |
6375 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6376 | * vma. | |
6377 | */ | |
26cb63ad | 6378 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6379 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6380 | |
1e0fb9ec | 6381 | if (event->pmu->event_mapped) |
bfe33492 | 6382 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6383 | |
7b732a75 | 6384 | return ret; |
37d81828 PM |
6385 | } |
6386 | ||
3c446b3d PZ |
6387 | static int perf_fasync(int fd, struct file *filp, int on) |
6388 | { | |
496ad9aa | 6389 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6390 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6391 | int retval; |
6392 | ||
5955102c | 6393 | inode_lock(inode); |
cdd6c482 | 6394 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6395 | inode_unlock(inode); |
3c446b3d PZ |
6396 | |
6397 | if (retval < 0) | |
6398 | return retval; | |
6399 | ||
6400 | return 0; | |
6401 | } | |
6402 | ||
0793a61d | 6403 | static const struct file_operations perf_fops = { |
3326c1ce | 6404 | .llseek = no_llseek, |
0793a61d TG |
6405 | .release = perf_release, |
6406 | .read = perf_read, | |
6407 | .poll = perf_poll, | |
d859e29f | 6408 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6409 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6410 | .mmap = perf_mmap, |
3c446b3d | 6411 | .fasync = perf_fasync, |
0793a61d TG |
6412 | }; |
6413 | ||
925d519a | 6414 | /* |
cdd6c482 | 6415 | * Perf event wakeup |
925d519a PZ |
6416 | * |
6417 | * If there's data, ensure we set the poll() state and publish everything | |
6418 | * to user-space before waking everybody up. | |
6419 | */ | |
6420 | ||
fed66e2c PZ |
6421 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6422 | { | |
6423 | /* only the parent has fasync state */ | |
6424 | if (event->parent) | |
6425 | event = event->parent; | |
6426 | return &event->fasync; | |
6427 | } | |
6428 | ||
cdd6c482 | 6429 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6430 | { |
10c6db11 | 6431 | ring_buffer_wakeup(event); |
4c9e2542 | 6432 | |
cdd6c482 | 6433 | if (event->pending_kill) { |
fed66e2c | 6434 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6435 | event->pending_kill = 0; |
4c9e2542 | 6436 | } |
925d519a PZ |
6437 | } |
6438 | ||
97ba62b2 ME |
6439 | static void perf_sigtrap(struct perf_event *event) |
6440 | { | |
97ba62b2 ME |
6441 | /* |
6442 | * We'd expect this to only occur if the irq_work is delayed and either | |
6443 | * ctx->task or current has changed in the meantime. This can be the | |
6444 | * case on architectures that do not implement arch_irq_work_raise(). | |
6445 | */ | |
6446 | if (WARN_ON_ONCE(event->ctx->task != current)) | |
6447 | return; | |
6448 | ||
6449 | /* | |
6450 | * perf_pending_event() can race with the task exiting. | |
6451 | */ | |
6452 | if (current->flags & PF_EXITING) | |
6453 | return; | |
6454 | ||
af5eeab7 EB |
6455 | force_sig_perf((void __user *)event->pending_addr, |
6456 | event->attr.type, event->attr.sig_data); | |
97ba62b2 ME |
6457 | } |
6458 | ||
1d54ad94 PZ |
6459 | static void perf_pending_event_disable(struct perf_event *event) |
6460 | { | |
6461 | int cpu = READ_ONCE(event->pending_disable); | |
6462 | ||
6463 | if (cpu < 0) | |
6464 | return; | |
6465 | ||
6466 | if (cpu == smp_processor_id()) { | |
6467 | WRITE_ONCE(event->pending_disable, -1); | |
97ba62b2 ME |
6468 | |
6469 | if (event->attr.sigtrap) { | |
6470 | perf_sigtrap(event); | |
6471 | atomic_set_release(&event->event_limit, 1); /* rearm event */ | |
6472 | return; | |
6473 | } | |
6474 | ||
1d54ad94 PZ |
6475 | perf_event_disable_local(event); |
6476 | return; | |
6477 | } | |
6478 | ||
6479 | /* | |
6480 | * CPU-A CPU-B | |
6481 | * | |
6482 | * perf_event_disable_inatomic() | |
6483 | * @pending_disable = CPU-A; | |
6484 | * irq_work_queue(); | |
6485 | * | |
6486 | * sched-out | |
6487 | * @pending_disable = -1; | |
6488 | * | |
6489 | * sched-in | |
6490 | * perf_event_disable_inatomic() | |
6491 | * @pending_disable = CPU-B; | |
6492 | * irq_work_queue(); // FAILS | |
6493 | * | |
6494 | * irq_work_run() | |
6495 | * perf_pending_event() | |
6496 | * | |
6497 | * But the event runs on CPU-B and wants disabling there. | |
6498 | */ | |
6499 | irq_work_queue_on(&event->pending, cpu); | |
6500 | } | |
6501 | ||
e360adbe | 6502 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6503 | { |
1d54ad94 | 6504 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6505 | int rctx; |
6506 | ||
6507 | rctx = perf_swevent_get_recursion_context(); | |
6508 | /* | |
6509 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6510 | * and we won't recurse 'further'. | |
6511 | */ | |
79f14641 | 6512 | |
1d54ad94 | 6513 | perf_pending_event_disable(event); |
79f14641 | 6514 | |
cdd6c482 IM |
6515 | if (event->pending_wakeup) { |
6516 | event->pending_wakeup = 0; | |
6517 | perf_event_wakeup(event); | |
79f14641 | 6518 | } |
d525211f PZ |
6519 | |
6520 | if (rctx >= 0) | |
6521 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6522 | } |
6523 | ||
39447b38 ZY |
6524 | /* |
6525 | * We assume there is only KVM supporting the callbacks. | |
6526 | * Later on, we might change it to a list if there is | |
6527 | * another virtualization implementation supporting the callbacks. | |
6528 | */ | |
6529 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6530 | ||
6531 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6532 | { | |
6533 | perf_guest_cbs = cbs; | |
6534 | return 0; | |
6535 | } | |
6536 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6537 | ||
6538 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6539 | { | |
6540 | perf_guest_cbs = NULL; | |
6541 | return 0; | |
6542 | } | |
6543 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6544 | ||
4018994f JO |
6545 | static void |
6546 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6547 | struct pt_regs *regs, u64 mask) | |
6548 | { | |
6549 | int bit; | |
29dd3288 | 6550 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6551 | |
29dd3288 MS |
6552 | bitmap_from_u64(_mask, mask); |
6553 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6554 | u64 val; |
6555 | ||
6556 | val = perf_reg_value(regs, bit); | |
6557 | perf_output_put(handle, val); | |
6558 | } | |
6559 | } | |
6560 | ||
60e2364e | 6561 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
76a4efa8 | 6562 | struct pt_regs *regs) |
4018994f | 6563 | { |
88a7c26a AL |
6564 | if (user_mode(regs)) { |
6565 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6566 | regs_user->regs = regs; |
085ebfe9 | 6567 | } else if (!(current->flags & PF_KTHREAD)) { |
76a4efa8 | 6568 | perf_get_regs_user(regs_user, regs); |
2565711f PZ |
6569 | } else { |
6570 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6571 | regs_user->regs = NULL; | |
4018994f JO |
6572 | } |
6573 | } | |
6574 | ||
60e2364e SE |
6575 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6576 | struct pt_regs *regs) | |
6577 | { | |
6578 | regs_intr->regs = regs; | |
6579 | regs_intr->abi = perf_reg_abi(current); | |
6580 | } | |
6581 | ||
6582 | ||
c5ebcedb JO |
6583 | /* |
6584 | * Get remaining task size from user stack pointer. | |
6585 | * | |
6586 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6587 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6588 | * so using TASK_SIZE as limit. |
6589 | */ | |
6590 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6591 | { | |
6592 | unsigned long addr = perf_user_stack_pointer(regs); | |
6593 | ||
6594 | if (!addr || addr >= TASK_SIZE) | |
6595 | return 0; | |
6596 | ||
6597 | return TASK_SIZE - addr; | |
6598 | } | |
6599 | ||
6600 | static u16 | |
6601 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6602 | struct pt_regs *regs) | |
6603 | { | |
6604 | u64 task_size; | |
6605 | ||
6606 | /* No regs, no stack pointer, no dump. */ | |
6607 | if (!regs) | |
6608 | return 0; | |
6609 | ||
6610 | /* | |
6611 | * Check if we fit in with the requested stack size into the: | |
6612 | * - TASK_SIZE | |
6613 | * If we don't, we limit the size to the TASK_SIZE. | |
6614 | * | |
6615 | * - remaining sample size | |
6616 | * If we don't, we customize the stack size to | |
6617 | * fit in to the remaining sample size. | |
6618 | */ | |
6619 | ||
6620 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6621 | stack_size = min(stack_size, (u16) task_size); | |
6622 | ||
6623 | /* Current header size plus static size and dynamic size. */ | |
6624 | header_size += 2 * sizeof(u64); | |
6625 | ||
6626 | /* Do we fit in with the current stack dump size? */ | |
6627 | if ((u16) (header_size + stack_size) < header_size) { | |
6628 | /* | |
6629 | * If we overflow the maximum size for the sample, | |
6630 | * we customize the stack dump size to fit in. | |
6631 | */ | |
6632 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6633 | stack_size = round_up(stack_size, sizeof(u64)); | |
6634 | } | |
6635 | ||
6636 | return stack_size; | |
6637 | } | |
6638 | ||
6639 | static void | |
6640 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6641 | struct pt_regs *regs) | |
6642 | { | |
6643 | /* Case of a kernel thread, nothing to dump */ | |
6644 | if (!regs) { | |
6645 | u64 size = 0; | |
6646 | perf_output_put(handle, size); | |
6647 | } else { | |
6648 | unsigned long sp; | |
6649 | unsigned int rem; | |
6650 | u64 dyn_size; | |
02e18447 | 6651 | mm_segment_t fs; |
c5ebcedb JO |
6652 | |
6653 | /* | |
6654 | * We dump: | |
6655 | * static size | |
6656 | * - the size requested by user or the best one we can fit | |
6657 | * in to the sample max size | |
6658 | * data | |
6659 | * - user stack dump data | |
6660 | * dynamic size | |
6661 | * - the actual dumped size | |
6662 | */ | |
6663 | ||
6664 | /* Static size. */ | |
6665 | perf_output_put(handle, dump_size); | |
6666 | ||
6667 | /* Data. */ | |
6668 | sp = perf_user_stack_pointer(regs); | |
3d13f313 | 6669 | fs = force_uaccess_begin(); |
c5ebcedb | 6670 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
3d13f313 | 6671 | force_uaccess_end(fs); |
c5ebcedb JO |
6672 | dyn_size = dump_size - rem; |
6673 | ||
6674 | perf_output_skip(handle, rem); | |
6675 | ||
6676 | /* Dynamic size. */ | |
6677 | perf_output_put(handle, dyn_size); | |
6678 | } | |
6679 | } | |
6680 | ||
a4faf00d AS |
6681 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6682 | struct perf_sample_data *data, | |
6683 | size_t size) | |
6684 | { | |
6685 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6686 | struct perf_buffer *rb; |
a4faf00d AS |
6687 | |
6688 | data->aux_size = 0; | |
6689 | ||
6690 | if (!sampler) | |
6691 | goto out; | |
6692 | ||
6693 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6694 | goto out; | |
6695 | ||
6696 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6697 | goto out; | |
6698 | ||
6699 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6700 | if (!rb) | |
6701 | goto out; | |
6702 | ||
6703 | /* | |
6704 | * If this is an NMI hit inside sampling code, don't take | |
6705 | * the sample. See also perf_aux_sample_output(). | |
6706 | */ | |
6707 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6708 | data->aux_size = 0; | |
6709 | } else { | |
6710 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6711 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6712 | } | |
6713 | ring_buffer_put(rb); | |
6714 | ||
6715 | out: | |
6716 | return data->aux_size; | |
6717 | } | |
6718 | ||
32961aec HX |
6719 | static long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
6720 | struct perf_event *event, | |
6721 | struct perf_output_handle *handle, | |
6722 | unsigned long size) | |
a4faf00d AS |
6723 | { |
6724 | unsigned long flags; | |
6725 | long ret; | |
6726 | ||
6727 | /* | |
6728 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6729 | * paths. If we start calling them in NMI context, they may race with | |
6730 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6731 | * been stopped, which is why we're using a separate callback that | |
6732 | * doesn't change the event state. | |
6733 | * | |
6734 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6735 | */ | |
6736 | local_irq_save(flags); | |
6737 | /* | |
6738 | * Guard against NMI hits inside the critical section; | |
6739 | * see also perf_prepare_sample_aux(). | |
6740 | */ | |
6741 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6742 | barrier(); | |
6743 | ||
6744 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6745 | ||
6746 | barrier(); | |
6747 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6748 | local_irq_restore(flags); | |
6749 | ||
6750 | return ret; | |
6751 | } | |
6752 | ||
6753 | static void perf_aux_sample_output(struct perf_event *event, | |
6754 | struct perf_output_handle *handle, | |
6755 | struct perf_sample_data *data) | |
6756 | { | |
6757 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6758 | struct perf_buffer *rb; |
a4faf00d | 6759 | unsigned long pad; |
a4faf00d AS |
6760 | long size; |
6761 | ||
6762 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6763 | return; | |
6764 | ||
6765 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6766 | if (!rb) | |
6767 | return; | |
6768 | ||
6769 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6770 | ||
6771 | /* | |
6772 | * An error here means that perf_output_copy() failed (returned a | |
6773 | * non-zero surplus that it didn't copy), which in its current | |
6774 | * enlightened implementation is not possible. If that changes, we'd | |
6775 | * like to know. | |
6776 | */ | |
6777 | if (WARN_ON_ONCE(size < 0)) | |
6778 | goto out_put; | |
6779 | ||
6780 | /* | |
6781 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6782 | * perf_prepare_sample_aux(), so should not be more than that. | |
6783 | */ | |
6784 | pad = data->aux_size - size; | |
6785 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6786 | pad = 8; | |
6787 | ||
6788 | if (pad) { | |
6789 | u64 zero = 0; | |
6790 | perf_output_copy(handle, &zero, pad); | |
6791 | } | |
6792 | ||
6793 | out_put: | |
6794 | ring_buffer_put(rb); | |
6795 | } | |
6796 | ||
c980d109 ACM |
6797 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6798 | struct perf_sample_data *data, | |
6799 | struct perf_event *event) | |
6844c09d ACM |
6800 | { |
6801 | u64 sample_type = event->attr.sample_type; | |
6802 | ||
6803 | data->type = sample_type; | |
6804 | header->size += event->id_header_size; | |
6805 | ||
6806 | if (sample_type & PERF_SAMPLE_TID) { | |
6807 | /* namespace issues */ | |
6808 | data->tid_entry.pid = perf_event_pid(event, current); | |
6809 | data->tid_entry.tid = perf_event_tid(event, current); | |
6810 | } | |
6811 | ||
6812 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6813 | data->time = perf_event_clock(event); |
6844c09d | 6814 | |
ff3d527c | 6815 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6816 | data->id = primary_event_id(event); |
6817 | ||
6818 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6819 | data->stream_id = event->id; | |
6820 | ||
6821 | if (sample_type & PERF_SAMPLE_CPU) { | |
6822 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6823 | data->cpu_entry.reserved = 0; | |
6824 | } | |
6825 | } | |
6826 | ||
76369139 FW |
6827 | void perf_event_header__init_id(struct perf_event_header *header, |
6828 | struct perf_sample_data *data, | |
6829 | struct perf_event *event) | |
c980d109 ACM |
6830 | { |
6831 | if (event->attr.sample_id_all) | |
6832 | __perf_event_header__init_id(header, data, event); | |
6833 | } | |
6834 | ||
6835 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6836 | struct perf_sample_data *data) | |
6837 | { | |
6838 | u64 sample_type = data->type; | |
6839 | ||
6840 | if (sample_type & PERF_SAMPLE_TID) | |
6841 | perf_output_put(handle, data->tid_entry); | |
6842 | ||
6843 | if (sample_type & PERF_SAMPLE_TIME) | |
6844 | perf_output_put(handle, data->time); | |
6845 | ||
6846 | if (sample_type & PERF_SAMPLE_ID) | |
6847 | perf_output_put(handle, data->id); | |
6848 | ||
6849 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6850 | perf_output_put(handle, data->stream_id); | |
6851 | ||
6852 | if (sample_type & PERF_SAMPLE_CPU) | |
6853 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6854 | |
6855 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6856 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6857 | } |
6858 | ||
76369139 FW |
6859 | void perf_event__output_id_sample(struct perf_event *event, |
6860 | struct perf_output_handle *handle, | |
6861 | struct perf_sample_data *sample) | |
c980d109 ACM |
6862 | { |
6863 | if (event->attr.sample_id_all) | |
6864 | __perf_event__output_id_sample(handle, sample); | |
6865 | } | |
6866 | ||
3dab77fb | 6867 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6868 | struct perf_event *event, |
6869 | u64 enabled, u64 running) | |
3dab77fb | 6870 | { |
cdd6c482 | 6871 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6872 | u64 values[4]; |
6873 | int n = 0; | |
6874 | ||
b5e58793 | 6875 | values[n++] = perf_event_count(event); |
3dab77fb | 6876 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6877 | values[n++] = enabled + |
cdd6c482 | 6878 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6879 | } |
6880 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6881 | values[n++] = running + |
cdd6c482 | 6882 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6883 | } |
6884 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6885 | values[n++] = primary_event_id(event); |
3dab77fb | 6886 | |
76369139 | 6887 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6888 | } |
6889 | ||
3dab77fb | 6890 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6891 | struct perf_event *event, |
6892 | u64 enabled, u64 running) | |
3dab77fb | 6893 | { |
cdd6c482 IM |
6894 | struct perf_event *leader = event->group_leader, *sub; |
6895 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6896 | u64 values[5]; |
6897 | int n = 0; | |
6898 | ||
6899 | values[n++] = 1 + leader->nr_siblings; | |
6900 | ||
6901 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6902 | values[n++] = enabled; |
3dab77fb PZ |
6903 | |
6904 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6905 | values[n++] = running; |
3dab77fb | 6906 | |
9e5b127d PZ |
6907 | if ((leader != event) && |
6908 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6909 | leader->pmu->read(leader); |
6910 | ||
b5e58793 | 6911 | values[n++] = perf_event_count(leader); |
3dab77fb | 6912 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6913 | values[n++] = primary_event_id(leader); |
3dab77fb | 6914 | |
76369139 | 6915 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6916 | |
edb39592 | 6917 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6918 | n = 0; |
6919 | ||
6f5ab001 JO |
6920 | if ((sub != event) && |
6921 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6922 | sub->pmu->read(sub); |
6923 | ||
b5e58793 | 6924 | values[n++] = perf_event_count(sub); |
3dab77fb | 6925 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6926 | values[n++] = primary_event_id(sub); |
3dab77fb | 6927 | |
76369139 | 6928 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6929 | } |
6930 | } | |
6931 | ||
eed01528 SE |
6932 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6933 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6934 | ||
ba5213ae PZ |
6935 | /* |
6936 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6937 | * | |
6938 | * The problem is that its both hard and excessively expensive to iterate the | |
6939 | * child list, not to mention that its impossible to IPI the children running | |
6940 | * on another CPU, from interrupt/NMI context. | |
6941 | */ | |
3dab77fb | 6942 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6943 | struct perf_event *event) |
3dab77fb | 6944 | { |
e3f3541c | 6945 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6946 | u64 read_format = event->attr.read_format; |
6947 | ||
6948 | /* | |
6949 | * compute total_time_enabled, total_time_running | |
6950 | * based on snapshot values taken when the event | |
6951 | * was last scheduled in. | |
6952 | * | |
6953 | * we cannot simply called update_context_time() | |
6954 | * because of locking issue as we are called in | |
6955 | * NMI context | |
6956 | */ | |
c4794295 | 6957 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6958 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6959 | |
cdd6c482 | 6960 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6961 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6962 | else |
eed01528 | 6963 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6964 | } |
6965 | ||
bbfd5e4f KL |
6966 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6967 | { | |
6968 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6969 | } | |
6970 | ||
5622f295 MM |
6971 | void perf_output_sample(struct perf_output_handle *handle, |
6972 | struct perf_event_header *header, | |
6973 | struct perf_sample_data *data, | |
cdd6c482 | 6974 | struct perf_event *event) |
5622f295 MM |
6975 | { |
6976 | u64 sample_type = data->type; | |
6977 | ||
6978 | perf_output_put(handle, *header); | |
6979 | ||
ff3d527c AH |
6980 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6981 | perf_output_put(handle, data->id); | |
6982 | ||
5622f295 MM |
6983 | if (sample_type & PERF_SAMPLE_IP) |
6984 | perf_output_put(handle, data->ip); | |
6985 | ||
6986 | if (sample_type & PERF_SAMPLE_TID) | |
6987 | perf_output_put(handle, data->tid_entry); | |
6988 | ||
6989 | if (sample_type & PERF_SAMPLE_TIME) | |
6990 | perf_output_put(handle, data->time); | |
6991 | ||
6992 | if (sample_type & PERF_SAMPLE_ADDR) | |
6993 | perf_output_put(handle, data->addr); | |
6994 | ||
6995 | if (sample_type & PERF_SAMPLE_ID) | |
6996 | perf_output_put(handle, data->id); | |
6997 | ||
6998 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6999 | perf_output_put(handle, data->stream_id); | |
7000 | ||
7001 | if (sample_type & PERF_SAMPLE_CPU) | |
7002 | perf_output_put(handle, data->cpu_entry); | |
7003 | ||
7004 | if (sample_type & PERF_SAMPLE_PERIOD) | |
7005 | perf_output_put(handle, data->period); | |
7006 | ||
7007 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 7008 | perf_output_read(handle, event); |
5622f295 MM |
7009 | |
7010 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 7011 | int size = 1; |
5622f295 | 7012 | |
99e818cc JO |
7013 | size += data->callchain->nr; |
7014 | size *= sizeof(u64); | |
7015 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
7016 | } |
7017 | ||
7018 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
7019 | struct perf_raw_record *raw = data->raw; |
7020 | ||
7021 | if (raw) { | |
7022 | struct perf_raw_frag *frag = &raw->frag; | |
7023 | ||
7024 | perf_output_put(handle, raw->size); | |
7025 | do { | |
7026 | if (frag->copy) { | |
7027 | __output_custom(handle, frag->copy, | |
7028 | frag->data, frag->size); | |
7029 | } else { | |
7030 | __output_copy(handle, frag->data, | |
7031 | frag->size); | |
7032 | } | |
7033 | if (perf_raw_frag_last(frag)) | |
7034 | break; | |
7035 | frag = frag->next; | |
7036 | } while (1); | |
7037 | if (frag->pad) | |
7038 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
7039 | } else { |
7040 | struct { | |
7041 | u32 size; | |
7042 | u32 data; | |
7043 | } raw = { | |
7044 | .size = sizeof(u32), | |
7045 | .data = 0, | |
7046 | }; | |
7047 | perf_output_put(handle, raw); | |
7048 | } | |
7049 | } | |
a7ac67ea | 7050 | |
bce38cd5 SE |
7051 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
7052 | if (data->br_stack) { | |
7053 | size_t size; | |
7054 | ||
7055 | size = data->br_stack->nr | |
7056 | * sizeof(struct perf_branch_entry); | |
7057 | ||
7058 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
7059 | if (perf_sample_save_hw_index(event)) |
7060 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
7061 | perf_output_copy(handle, data->br_stack->entries, size); |
7062 | } else { | |
7063 | /* | |
7064 | * we always store at least the value of nr | |
7065 | */ | |
7066 | u64 nr = 0; | |
7067 | perf_output_put(handle, nr); | |
7068 | } | |
7069 | } | |
4018994f JO |
7070 | |
7071 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
7072 | u64 abi = data->regs_user.abi; | |
7073 | ||
7074 | /* | |
7075 | * If there are no regs to dump, notice it through | |
7076 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
7077 | */ | |
7078 | perf_output_put(handle, abi); | |
7079 | ||
7080 | if (abi) { | |
7081 | u64 mask = event->attr.sample_regs_user; | |
7082 | perf_output_sample_regs(handle, | |
7083 | data->regs_user.regs, | |
7084 | mask); | |
7085 | } | |
7086 | } | |
c5ebcedb | 7087 | |
a5cdd40c | 7088 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
7089 | perf_output_sample_ustack(handle, |
7090 | data->stack_user_size, | |
7091 | data->regs_user.regs); | |
a5cdd40c | 7092 | } |
c3feedf2 | 7093 | |
2a6c6b7d KL |
7094 | if (sample_type & PERF_SAMPLE_WEIGHT_TYPE) |
7095 | perf_output_put(handle, data->weight.full); | |
d6be9ad6 SE |
7096 | |
7097 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
7098 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 7099 | |
fdfbbd07 AK |
7100 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
7101 | perf_output_put(handle, data->txn); | |
7102 | ||
60e2364e SE |
7103 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
7104 | u64 abi = data->regs_intr.abi; | |
7105 | /* | |
7106 | * If there are no regs to dump, notice it through | |
7107 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
7108 | */ | |
7109 | perf_output_put(handle, abi); | |
7110 | ||
7111 | if (abi) { | |
7112 | u64 mask = event->attr.sample_regs_intr; | |
7113 | ||
7114 | perf_output_sample_regs(handle, | |
7115 | data->regs_intr.regs, | |
7116 | mask); | |
7117 | } | |
7118 | } | |
7119 | ||
fc7ce9c7 KL |
7120 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
7121 | perf_output_put(handle, data->phys_addr); | |
7122 | ||
6546b19f NK |
7123 | if (sample_type & PERF_SAMPLE_CGROUP) |
7124 | perf_output_put(handle, data->cgroup); | |
7125 | ||
8d97e718 KL |
7126 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
7127 | perf_output_put(handle, data->data_page_size); | |
7128 | ||
995f088e SE |
7129 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7130 | perf_output_put(handle, data->code_page_size); | |
7131 | ||
a4faf00d AS |
7132 | if (sample_type & PERF_SAMPLE_AUX) { |
7133 | perf_output_put(handle, data->aux_size); | |
7134 | ||
7135 | if (data->aux_size) | |
7136 | perf_aux_sample_output(event, handle, data); | |
7137 | } | |
7138 | ||
a5cdd40c PZ |
7139 | if (!event->attr.watermark) { |
7140 | int wakeup_events = event->attr.wakeup_events; | |
7141 | ||
7142 | if (wakeup_events) { | |
56de4e8f | 7143 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
7144 | int events = local_inc_return(&rb->events); |
7145 | ||
7146 | if (events >= wakeup_events) { | |
7147 | local_sub(wakeup_events, &rb->events); | |
7148 | local_inc(&rb->wakeup); | |
7149 | } | |
7150 | } | |
7151 | } | |
5622f295 MM |
7152 | } |
7153 | ||
fc7ce9c7 KL |
7154 | static u64 perf_virt_to_phys(u64 virt) |
7155 | { | |
7156 | u64 phys_addr = 0; | |
7157 | struct page *p = NULL; | |
7158 | ||
7159 | if (!virt) | |
7160 | return 0; | |
7161 | ||
7162 | if (virt >= TASK_SIZE) { | |
7163 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
7164 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
7165 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
7166 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
7167 | } else { | |
7168 | /* | |
7169 | * Walking the pages tables for user address. | |
7170 | * Interrupts are disabled, so it prevents any tear down | |
7171 | * of the page tables. | |
dadbb612 | 7172 | * Try IRQ-safe get_user_page_fast_only first. |
fc7ce9c7 KL |
7173 | * If failed, leave phys_addr as 0. |
7174 | */ | |
d3296fb3 JO |
7175 | if (current->mm != NULL) { |
7176 | pagefault_disable(); | |
dadbb612 | 7177 | if (get_user_page_fast_only(virt, 0, &p)) |
d3296fb3 JO |
7178 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; |
7179 | pagefault_enable(); | |
7180 | } | |
fc7ce9c7 KL |
7181 | |
7182 | if (p) | |
7183 | put_page(p); | |
7184 | } | |
7185 | ||
7186 | return phys_addr; | |
7187 | } | |
7188 | ||
8d97e718 | 7189 | /* |
8af26be0 | 7190 | * Return the pagetable size of a given virtual address. |
8d97e718 | 7191 | */ |
8af26be0 | 7192 | static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) |
8d97e718 | 7193 | { |
8af26be0 | 7194 | u64 size = 0; |
8d97e718 | 7195 | |
8af26be0 PZ |
7196 | #ifdef CONFIG_HAVE_FAST_GUP |
7197 | pgd_t *pgdp, pgd; | |
7198 | p4d_t *p4dp, p4d; | |
7199 | pud_t *pudp, pud; | |
7200 | pmd_t *pmdp, pmd; | |
7201 | pte_t *ptep, pte; | |
8d97e718 | 7202 | |
8af26be0 PZ |
7203 | pgdp = pgd_offset(mm, addr); |
7204 | pgd = READ_ONCE(*pgdp); | |
7205 | if (pgd_none(pgd)) | |
8d97e718 KL |
7206 | return 0; |
7207 | ||
8af26be0 PZ |
7208 | if (pgd_leaf(pgd)) |
7209 | return pgd_leaf_size(pgd); | |
8d97e718 | 7210 | |
8af26be0 PZ |
7211 | p4dp = p4d_offset_lockless(pgdp, pgd, addr); |
7212 | p4d = READ_ONCE(*p4dp); | |
7213 | if (!p4d_present(p4d)) | |
8d97e718 KL |
7214 | return 0; |
7215 | ||
8af26be0 PZ |
7216 | if (p4d_leaf(p4d)) |
7217 | return p4d_leaf_size(p4d); | |
8d97e718 | 7218 | |
8af26be0 PZ |
7219 | pudp = pud_offset_lockless(p4dp, p4d, addr); |
7220 | pud = READ_ONCE(*pudp); | |
7221 | if (!pud_present(pud)) | |
8d97e718 KL |
7222 | return 0; |
7223 | ||
8af26be0 PZ |
7224 | if (pud_leaf(pud)) |
7225 | return pud_leaf_size(pud); | |
8d97e718 | 7226 | |
8af26be0 PZ |
7227 | pmdp = pmd_offset_lockless(pudp, pud, addr); |
7228 | pmd = READ_ONCE(*pmdp); | |
7229 | if (!pmd_present(pmd)) | |
8d97e718 | 7230 | return 0; |
8d97e718 | 7231 | |
8af26be0 PZ |
7232 | if (pmd_leaf(pmd)) |
7233 | return pmd_leaf_size(pmd); | |
51b646b2 | 7234 | |
8af26be0 PZ |
7235 | ptep = pte_offset_map(&pmd, addr); |
7236 | pte = ptep_get_lockless(ptep); | |
7237 | if (pte_present(pte)) | |
7238 | size = pte_leaf_size(pte); | |
7239 | pte_unmap(ptep); | |
7240 | #endif /* CONFIG_HAVE_FAST_GUP */ | |
8d97e718 | 7241 | |
8af26be0 | 7242 | return size; |
8d97e718 KL |
7243 | } |
7244 | ||
8d97e718 KL |
7245 | static u64 perf_get_page_size(unsigned long addr) |
7246 | { | |
7247 | struct mm_struct *mm; | |
7248 | unsigned long flags; | |
7249 | u64 size; | |
7250 | ||
7251 | if (!addr) | |
7252 | return 0; | |
7253 | ||
7254 | /* | |
7255 | * Software page-table walkers must disable IRQs, | |
7256 | * which prevents any tear down of the page tables. | |
7257 | */ | |
7258 | local_irq_save(flags); | |
7259 | ||
7260 | mm = current->mm; | |
7261 | if (!mm) { | |
7262 | /* | |
7263 | * For kernel threads and the like, use init_mm so that | |
7264 | * we can find kernel memory. | |
7265 | */ | |
7266 | mm = &init_mm; | |
7267 | } | |
7268 | ||
8af26be0 | 7269 | size = perf_get_pgtable_size(mm, addr); |
8d97e718 KL |
7270 | |
7271 | local_irq_restore(flags); | |
7272 | ||
7273 | return size; | |
7274 | } | |
7275 | ||
99e818cc JO |
7276 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
7277 | ||
6cbc304f | 7278 | struct perf_callchain_entry * |
8cf7e0e2 JO |
7279 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
7280 | { | |
7281 | bool kernel = !event->attr.exclude_callchain_kernel; | |
7282 | bool user = !event->attr.exclude_callchain_user; | |
7283 | /* Disallow cross-task user callchains. */ | |
7284 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
7285 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 7286 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
7287 | |
7288 | if (!kernel && !user) | |
99e818cc | 7289 | return &__empty_callchain; |
8cf7e0e2 | 7290 | |
99e818cc JO |
7291 | callchain = get_perf_callchain(regs, 0, kernel, user, |
7292 | max_stack, crosstask, true); | |
7293 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
7294 | } |
7295 | ||
5622f295 MM |
7296 | void perf_prepare_sample(struct perf_event_header *header, |
7297 | struct perf_sample_data *data, | |
cdd6c482 | 7298 | struct perf_event *event, |
5622f295 | 7299 | struct pt_regs *regs) |
7b732a75 | 7300 | { |
cdd6c482 | 7301 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 7302 | |
cdd6c482 | 7303 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 7304 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
7305 | |
7306 | header->misc = 0; | |
7307 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 7308 | |
c980d109 | 7309 | __perf_event_header__init_id(header, data, event); |
6844c09d | 7310 | |
995f088e | 7311 | if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE)) |
5622f295 MM |
7312 | data->ip = perf_instruction_pointer(regs); |
7313 | ||
b23f3325 | 7314 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 7315 | int size = 1; |
394ee076 | 7316 | |
6cbc304f PZ |
7317 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
7318 | data->callchain = perf_callchain(event, regs); | |
7319 | ||
99e818cc | 7320 | size += data->callchain->nr; |
5622f295 MM |
7321 | |
7322 | header->size += size * sizeof(u64); | |
394ee076 PZ |
7323 | } |
7324 | ||
3a43ce68 | 7325 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
7326 | struct perf_raw_record *raw = data->raw; |
7327 | int size; | |
7328 | ||
7329 | if (raw) { | |
7330 | struct perf_raw_frag *frag = &raw->frag; | |
7331 | u32 sum = 0; | |
7332 | ||
7333 | do { | |
7334 | sum += frag->size; | |
7335 | if (perf_raw_frag_last(frag)) | |
7336 | break; | |
7337 | frag = frag->next; | |
7338 | } while (1); | |
7339 | ||
7340 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
7341 | raw->size = size - sizeof(u32); | |
7342 | frag->pad = raw->size - sum; | |
7343 | } else { | |
7344 | size = sizeof(u64); | |
7345 | } | |
a044560c | 7346 | |
7e3f977e | 7347 | header->size += size; |
7f453c24 | 7348 | } |
bce38cd5 SE |
7349 | |
7350 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7351 | int size = sizeof(u64); /* nr */ | |
7352 | if (data->br_stack) { | |
bbfd5e4f KL |
7353 | if (perf_sample_save_hw_index(event)) |
7354 | size += sizeof(u64); | |
7355 | ||
bce38cd5 SE |
7356 | size += data->br_stack->nr |
7357 | * sizeof(struct perf_branch_entry); | |
7358 | } | |
7359 | header->size += size; | |
7360 | } | |
4018994f | 7361 | |
2565711f | 7362 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
76a4efa8 | 7363 | perf_sample_regs_user(&data->regs_user, regs); |
2565711f | 7364 | |
4018994f JO |
7365 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7366 | /* regs dump ABI info */ | |
7367 | int size = sizeof(u64); | |
7368 | ||
4018994f JO |
7369 | if (data->regs_user.regs) { |
7370 | u64 mask = event->attr.sample_regs_user; | |
7371 | size += hweight64(mask) * sizeof(u64); | |
7372 | } | |
7373 | ||
7374 | header->size += size; | |
7375 | } | |
c5ebcedb JO |
7376 | |
7377 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7378 | /* | |
9f014e3a | 7379 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7380 | * processed as the last one or have additional check added |
7381 | * in case new sample type is added, because we could eat | |
7382 | * up the rest of the sample size. | |
7383 | */ | |
c5ebcedb JO |
7384 | u16 stack_size = event->attr.sample_stack_user; |
7385 | u16 size = sizeof(u64); | |
7386 | ||
c5ebcedb | 7387 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7388 | data->regs_user.regs); |
c5ebcedb JO |
7389 | |
7390 | /* | |
7391 | * If there is something to dump, add space for the dump | |
7392 | * itself and for the field that tells the dynamic size, | |
7393 | * which is how many have been actually dumped. | |
7394 | */ | |
7395 | if (stack_size) | |
7396 | size += sizeof(u64) + stack_size; | |
7397 | ||
7398 | data->stack_user_size = stack_size; | |
7399 | header->size += size; | |
7400 | } | |
60e2364e SE |
7401 | |
7402 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7403 | /* regs dump ABI info */ | |
7404 | int size = sizeof(u64); | |
7405 | ||
7406 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7407 | ||
7408 | if (data->regs_intr.regs) { | |
7409 | u64 mask = event->attr.sample_regs_intr; | |
7410 | ||
7411 | size += hweight64(mask) * sizeof(u64); | |
7412 | } | |
7413 | ||
7414 | header->size += size; | |
7415 | } | |
fc7ce9c7 KL |
7416 | |
7417 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7418 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7419 | |
6546b19f NK |
7420 | #ifdef CONFIG_CGROUP_PERF |
7421 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7422 | struct cgroup *cgrp; | |
7423 | ||
7424 | /* protected by RCU */ | |
7425 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7426 | data->cgroup = cgroup_id(cgrp); | |
7427 | } | |
7428 | #endif | |
7429 | ||
8d97e718 KL |
7430 | /* |
7431 | * PERF_DATA_PAGE_SIZE requires PERF_SAMPLE_ADDR. If the user doesn't | |
7432 | * require PERF_SAMPLE_ADDR, kernel implicitly retrieve the data->addr, | |
7433 | * but the value will not dump to the userspace. | |
7434 | */ | |
7435 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) | |
7436 | data->data_page_size = perf_get_page_size(data->addr); | |
7437 | ||
995f088e SE |
7438 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7439 | data->code_page_size = perf_get_page_size(data->ip); | |
7440 | ||
a4faf00d AS |
7441 | if (sample_type & PERF_SAMPLE_AUX) { |
7442 | u64 size; | |
7443 | ||
7444 | header->size += sizeof(u64); /* size */ | |
7445 | ||
7446 | /* | |
7447 | * Given the 16bit nature of header::size, an AUX sample can | |
7448 | * easily overflow it, what with all the preceding sample bits. | |
7449 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7450 | * per sample in total (rounded down to 8 byte boundary). | |
7451 | */ | |
7452 | size = min_t(size_t, U16_MAX - header->size, | |
7453 | event->attr.aux_sample_size); | |
7454 | size = rounddown(size, 8); | |
7455 | size = perf_prepare_sample_aux(event, data, size); | |
7456 | ||
7457 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7458 | header->size += size; | |
7459 | } | |
7460 | /* | |
7461 | * If you're adding more sample types here, you likely need to do | |
7462 | * something about the overflowing header::size, like repurpose the | |
7463 | * lowest 3 bits of size, which should be always zero at the moment. | |
7464 | * This raises a more important question, do we really need 512k sized | |
7465 | * samples and why, so good argumentation is in order for whatever you | |
7466 | * do here next. | |
7467 | */ | |
7468 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7469 | } |
7f453c24 | 7470 | |
56201969 | 7471 | static __always_inline int |
9ecda41a WN |
7472 | __perf_event_output(struct perf_event *event, |
7473 | struct perf_sample_data *data, | |
7474 | struct pt_regs *regs, | |
7475 | int (*output_begin)(struct perf_output_handle *, | |
267fb273 | 7476 | struct perf_sample_data *, |
9ecda41a WN |
7477 | struct perf_event *, |
7478 | unsigned int)) | |
5622f295 MM |
7479 | { |
7480 | struct perf_output_handle handle; | |
7481 | struct perf_event_header header; | |
56201969 | 7482 | int err; |
689802b2 | 7483 | |
927c7a9e FW |
7484 | /* protect the callchain buffers */ |
7485 | rcu_read_lock(); | |
7486 | ||
cdd6c482 | 7487 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7488 | |
267fb273 | 7489 | err = output_begin(&handle, data, event, header.size); |
56201969 | 7490 | if (err) |
927c7a9e | 7491 | goto exit; |
0322cd6e | 7492 | |
cdd6c482 | 7493 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7494 | |
8a057d84 | 7495 | perf_output_end(&handle); |
927c7a9e FW |
7496 | |
7497 | exit: | |
7498 | rcu_read_unlock(); | |
56201969 | 7499 | return err; |
0322cd6e PZ |
7500 | } |
7501 | ||
9ecda41a WN |
7502 | void |
7503 | perf_event_output_forward(struct perf_event *event, | |
7504 | struct perf_sample_data *data, | |
7505 | struct pt_regs *regs) | |
7506 | { | |
7507 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7508 | } | |
7509 | ||
7510 | void | |
7511 | perf_event_output_backward(struct perf_event *event, | |
7512 | struct perf_sample_data *data, | |
7513 | struct pt_regs *regs) | |
7514 | { | |
7515 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7516 | } | |
7517 | ||
56201969 | 7518 | int |
9ecda41a WN |
7519 | perf_event_output(struct perf_event *event, |
7520 | struct perf_sample_data *data, | |
7521 | struct pt_regs *regs) | |
7522 | { | |
56201969 | 7523 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7524 | } |
7525 | ||
38b200d6 | 7526 | /* |
cdd6c482 | 7527 | * read event_id |
38b200d6 PZ |
7528 | */ |
7529 | ||
7530 | struct perf_read_event { | |
7531 | struct perf_event_header header; | |
7532 | ||
7533 | u32 pid; | |
7534 | u32 tid; | |
38b200d6 PZ |
7535 | }; |
7536 | ||
7537 | static void | |
cdd6c482 | 7538 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7539 | struct task_struct *task) |
7540 | { | |
7541 | struct perf_output_handle handle; | |
c980d109 | 7542 | struct perf_sample_data sample; |
dfc65094 | 7543 | struct perf_read_event read_event = { |
38b200d6 | 7544 | .header = { |
cdd6c482 | 7545 | .type = PERF_RECORD_READ, |
38b200d6 | 7546 | .misc = 0, |
c320c7b7 | 7547 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7548 | }, |
cdd6c482 IM |
7549 | .pid = perf_event_pid(event, task), |
7550 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7551 | }; |
3dab77fb | 7552 | int ret; |
38b200d6 | 7553 | |
c980d109 | 7554 | perf_event_header__init_id(&read_event.header, &sample, event); |
267fb273 | 7555 | ret = perf_output_begin(&handle, &sample, event, read_event.header.size); |
38b200d6 PZ |
7556 | if (ret) |
7557 | return; | |
7558 | ||
dfc65094 | 7559 | perf_output_put(&handle, read_event); |
cdd6c482 | 7560 | perf_output_read(&handle, event); |
c980d109 | 7561 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7562 | |
38b200d6 PZ |
7563 | perf_output_end(&handle); |
7564 | } | |
7565 | ||
aab5b71e | 7566 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7567 | |
7568 | static void | |
aab5b71e PZ |
7569 | perf_iterate_ctx(struct perf_event_context *ctx, |
7570 | perf_iterate_f output, | |
b73e4fef | 7571 | void *data, bool all) |
52d857a8 JO |
7572 | { |
7573 | struct perf_event *event; | |
7574 | ||
7575 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7576 | if (!all) { |
7577 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7578 | continue; | |
7579 | if (!event_filter_match(event)) | |
7580 | continue; | |
7581 | } | |
7582 | ||
67516844 | 7583 | output(event, data); |
52d857a8 JO |
7584 | } |
7585 | } | |
7586 | ||
aab5b71e | 7587 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7588 | { |
7589 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7590 | struct perf_event *event; | |
7591 | ||
7592 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7593 | /* |
7594 | * Skip events that are not fully formed yet; ensure that | |
7595 | * if we observe event->ctx, both event and ctx will be | |
7596 | * complete enough. See perf_install_in_context(). | |
7597 | */ | |
7598 | if (!smp_load_acquire(&event->ctx)) | |
7599 | continue; | |
7600 | ||
f2fb6bef KL |
7601 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7602 | continue; | |
7603 | if (!event_filter_match(event)) | |
7604 | continue; | |
7605 | output(event, data); | |
7606 | } | |
7607 | } | |
7608 | ||
aab5b71e PZ |
7609 | /* |
7610 | * Iterate all events that need to receive side-band events. | |
7611 | * | |
7612 | * For new callers; ensure that account_pmu_sb_event() includes | |
7613 | * your event, otherwise it might not get delivered. | |
7614 | */ | |
52d857a8 | 7615 | static void |
aab5b71e | 7616 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7617 | struct perf_event_context *task_ctx) |
7618 | { | |
52d857a8 | 7619 | struct perf_event_context *ctx; |
52d857a8 JO |
7620 | int ctxn; |
7621 | ||
aab5b71e PZ |
7622 | rcu_read_lock(); |
7623 | preempt_disable(); | |
7624 | ||
4e93ad60 | 7625 | /* |
aab5b71e PZ |
7626 | * If we have task_ctx != NULL we only notify the task context itself. |
7627 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7628 | * context. |
7629 | */ | |
7630 | if (task_ctx) { | |
aab5b71e PZ |
7631 | perf_iterate_ctx(task_ctx, output, data, false); |
7632 | goto done; | |
4e93ad60 JO |
7633 | } |
7634 | ||
aab5b71e | 7635 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7636 | |
7637 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7638 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7639 | if (ctx) | |
aab5b71e | 7640 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7641 | } |
aab5b71e | 7642 | done: |
f2fb6bef | 7643 | preempt_enable(); |
52d857a8 | 7644 | rcu_read_unlock(); |
95ff4ca2 AS |
7645 | } |
7646 | ||
375637bc AS |
7647 | /* |
7648 | * Clear all file-based filters at exec, they'll have to be | |
7649 | * re-instated when/if these objects are mmapped again. | |
7650 | */ | |
7651 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7652 | { | |
7653 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7654 | struct perf_addr_filter *filter; | |
7655 | unsigned int restart = 0, count = 0; | |
7656 | unsigned long flags; | |
7657 | ||
7658 | if (!has_addr_filter(event)) | |
7659 | return; | |
7660 | ||
7661 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7662 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7663 | if (filter->path.dentry) { |
c60f83b8 AS |
7664 | event->addr_filter_ranges[count].start = 0; |
7665 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7666 | restart++; |
7667 | } | |
7668 | ||
7669 | count++; | |
7670 | } | |
7671 | ||
7672 | if (restart) | |
7673 | event->addr_filters_gen++; | |
7674 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7675 | ||
7676 | if (restart) | |
767ae086 | 7677 | perf_event_stop(event, 1); |
375637bc AS |
7678 | } |
7679 | ||
7680 | void perf_event_exec(void) | |
7681 | { | |
7682 | struct perf_event_context *ctx; | |
7683 | int ctxn; | |
7684 | ||
375637bc | 7685 | for_each_task_context_nr(ctxn) { |
375637bc | 7686 | perf_event_enable_on_exec(ctxn); |
2e498d0a | 7687 | perf_event_remove_on_exec(ctxn); |
375637bc | 7688 | |
2e498d0a ME |
7689 | rcu_read_lock(); |
7690 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7691 | if (ctx) { | |
7692 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, | |
7693 | NULL, true); | |
7694 | } | |
7695 | rcu_read_unlock(); | |
375637bc | 7696 | } |
375637bc AS |
7697 | } |
7698 | ||
95ff4ca2 | 7699 | struct remote_output { |
56de4e8f | 7700 | struct perf_buffer *rb; |
95ff4ca2 AS |
7701 | int err; |
7702 | }; | |
7703 | ||
7704 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7705 | { | |
7706 | struct perf_event *parent = event->parent; | |
7707 | struct remote_output *ro = data; | |
56de4e8f | 7708 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7709 | struct stop_event_data sd = { |
7710 | .event = event, | |
7711 | }; | |
95ff4ca2 AS |
7712 | |
7713 | if (!has_aux(event)) | |
7714 | return; | |
7715 | ||
7716 | if (!parent) | |
7717 | parent = event; | |
7718 | ||
7719 | /* | |
7720 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7721 | * ring-buffer, but it will be the child that's actually using it. |
7722 | * | |
7723 | * We are using event::rb to determine if the event should be stopped, | |
7724 | * however this may race with ring_buffer_attach() (through set_output), | |
7725 | * which will make us skip the event that actually needs to be stopped. | |
7726 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7727 | * its rb pointer. | |
95ff4ca2 AS |
7728 | */ |
7729 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7730 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7731 | } |
7732 | ||
7733 | static int __perf_pmu_output_stop(void *info) | |
7734 | { | |
7735 | struct perf_event *event = info; | |
f3a519e4 | 7736 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7737 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7738 | struct remote_output ro = { |
7739 | .rb = event->rb, | |
7740 | }; | |
7741 | ||
7742 | rcu_read_lock(); | |
aab5b71e | 7743 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7744 | if (cpuctx->task_ctx) |
aab5b71e | 7745 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7746 | &ro, false); |
95ff4ca2 AS |
7747 | rcu_read_unlock(); |
7748 | ||
7749 | return ro.err; | |
7750 | } | |
7751 | ||
7752 | static void perf_pmu_output_stop(struct perf_event *event) | |
7753 | { | |
7754 | struct perf_event *iter; | |
7755 | int err, cpu; | |
7756 | ||
7757 | restart: | |
7758 | rcu_read_lock(); | |
7759 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7760 | /* | |
7761 | * For per-CPU events, we need to make sure that neither they | |
7762 | * nor their children are running; for cpu==-1 events it's | |
7763 | * sufficient to stop the event itself if it's active, since | |
7764 | * it can't have children. | |
7765 | */ | |
7766 | cpu = iter->cpu; | |
7767 | if (cpu == -1) | |
7768 | cpu = READ_ONCE(iter->oncpu); | |
7769 | ||
7770 | if (cpu == -1) | |
7771 | continue; | |
7772 | ||
7773 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7774 | if (err == -EAGAIN) { | |
7775 | rcu_read_unlock(); | |
7776 | goto restart; | |
7777 | } | |
7778 | } | |
7779 | rcu_read_unlock(); | |
52d857a8 JO |
7780 | } |
7781 | ||
60313ebe | 7782 | /* |
9f498cc5 PZ |
7783 | * task tracking -- fork/exit |
7784 | * | |
13d7a241 | 7785 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7786 | */ |
7787 | ||
9f498cc5 | 7788 | struct perf_task_event { |
3a80b4a3 | 7789 | struct task_struct *task; |
cdd6c482 | 7790 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7791 | |
7792 | struct { | |
7793 | struct perf_event_header header; | |
7794 | ||
7795 | u32 pid; | |
7796 | u32 ppid; | |
9f498cc5 PZ |
7797 | u32 tid; |
7798 | u32 ptid; | |
393b2ad8 | 7799 | u64 time; |
cdd6c482 | 7800 | } event_id; |
60313ebe PZ |
7801 | }; |
7802 | ||
67516844 JO |
7803 | static int perf_event_task_match(struct perf_event *event) |
7804 | { | |
13d7a241 SE |
7805 | return event->attr.comm || event->attr.mmap || |
7806 | event->attr.mmap2 || event->attr.mmap_data || | |
7807 | event->attr.task; | |
67516844 JO |
7808 | } |
7809 | ||
cdd6c482 | 7810 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7811 | void *data) |
60313ebe | 7812 | { |
52d857a8 | 7813 | struct perf_task_event *task_event = data; |
60313ebe | 7814 | struct perf_output_handle handle; |
c980d109 | 7815 | struct perf_sample_data sample; |
9f498cc5 | 7816 | struct task_struct *task = task_event->task; |
c980d109 | 7817 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7818 | |
67516844 JO |
7819 | if (!perf_event_task_match(event)) |
7820 | return; | |
7821 | ||
c980d109 | 7822 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7823 | |
267fb273 | 7824 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7825 | task_event->event_id.header.size); |
ef60777c | 7826 | if (ret) |
c980d109 | 7827 | goto out; |
60313ebe | 7828 | |
cdd6c482 | 7829 | task_event->event_id.pid = perf_event_pid(event, task); |
cdd6c482 | 7830 | task_event->event_id.tid = perf_event_tid(event, task); |
f3bed55e IR |
7831 | |
7832 | if (task_event->event_id.header.type == PERF_RECORD_EXIT) { | |
7833 | task_event->event_id.ppid = perf_event_pid(event, | |
7834 | task->real_parent); | |
7835 | task_event->event_id.ptid = perf_event_pid(event, | |
7836 | task->real_parent); | |
7837 | } else { /* PERF_RECORD_FORK */ | |
7838 | task_event->event_id.ppid = perf_event_pid(event, current); | |
7839 | task_event->event_id.ptid = perf_event_tid(event, current); | |
7840 | } | |
9f498cc5 | 7841 | |
34f43927 PZ |
7842 | task_event->event_id.time = perf_event_clock(event); |
7843 | ||
cdd6c482 | 7844 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7845 | |
c980d109 ACM |
7846 | perf_event__output_id_sample(event, &handle, &sample); |
7847 | ||
60313ebe | 7848 | perf_output_end(&handle); |
c980d109 ACM |
7849 | out: |
7850 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7851 | } |
7852 | ||
cdd6c482 IM |
7853 | static void perf_event_task(struct task_struct *task, |
7854 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7855 | int new) |
60313ebe | 7856 | { |
9f498cc5 | 7857 | struct perf_task_event task_event; |
60313ebe | 7858 | |
cdd6c482 IM |
7859 | if (!atomic_read(&nr_comm_events) && |
7860 | !atomic_read(&nr_mmap_events) && | |
7861 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7862 | return; |
7863 | ||
9f498cc5 | 7864 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7865 | .task = task, |
7866 | .task_ctx = task_ctx, | |
cdd6c482 | 7867 | .event_id = { |
60313ebe | 7868 | .header = { |
cdd6c482 | 7869 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7870 | .misc = 0, |
cdd6c482 | 7871 | .size = sizeof(task_event.event_id), |
60313ebe | 7872 | }, |
573402db PZ |
7873 | /* .pid */ |
7874 | /* .ppid */ | |
9f498cc5 PZ |
7875 | /* .tid */ |
7876 | /* .ptid */ | |
34f43927 | 7877 | /* .time */ |
60313ebe PZ |
7878 | }, |
7879 | }; | |
7880 | ||
aab5b71e | 7881 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7882 | &task_event, |
7883 | task_ctx); | |
9f498cc5 PZ |
7884 | } |
7885 | ||
cdd6c482 | 7886 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7887 | { |
cdd6c482 | 7888 | perf_event_task(task, NULL, 1); |
e4222673 | 7889 | perf_event_namespaces(task); |
60313ebe PZ |
7890 | } |
7891 | ||
8d1b2d93 PZ |
7892 | /* |
7893 | * comm tracking | |
7894 | */ | |
7895 | ||
7896 | struct perf_comm_event { | |
22a4f650 IM |
7897 | struct task_struct *task; |
7898 | char *comm; | |
8d1b2d93 PZ |
7899 | int comm_size; |
7900 | ||
7901 | struct { | |
7902 | struct perf_event_header header; | |
7903 | ||
7904 | u32 pid; | |
7905 | u32 tid; | |
cdd6c482 | 7906 | } event_id; |
8d1b2d93 PZ |
7907 | }; |
7908 | ||
67516844 JO |
7909 | static int perf_event_comm_match(struct perf_event *event) |
7910 | { | |
7911 | return event->attr.comm; | |
7912 | } | |
7913 | ||
cdd6c482 | 7914 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7915 | void *data) |
8d1b2d93 | 7916 | { |
52d857a8 | 7917 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7918 | struct perf_output_handle handle; |
c980d109 | 7919 | struct perf_sample_data sample; |
cdd6c482 | 7920 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7921 | int ret; |
7922 | ||
67516844 JO |
7923 | if (!perf_event_comm_match(event)) |
7924 | return; | |
7925 | ||
c980d109 | 7926 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
267fb273 | 7927 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7928 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7929 | |
7930 | if (ret) | |
c980d109 | 7931 | goto out; |
8d1b2d93 | 7932 | |
cdd6c482 IM |
7933 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7934 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7935 | |
cdd6c482 | 7936 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7937 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7938 | comm_event->comm_size); |
c980d109 ACM |
7939 | |
7940 | perf_event__output_id_sample(event, &handle, &sample); | |
7941 | ||
8d1b2d93 | 7942 | perf_output_end(&handle); |
c980d109 ACM |
7943 | out: |
7944 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7945 | } |
7946 | ||
cdd6c482 | 7947 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7948 | { |
413ee3b4 | 7949 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7950 | unsigned int size; |
8d1b2d93 | 7951 | |
413ee3b4 | 7952 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7953 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7954 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7955 | |
7956 | comm_event->comm = comm; | |
7957 | comm_event->comm_size = size; | |
7958 | ||
cdd6c482 | 7959 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7960 | |
aab5b71e | 7961 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7962 | comm_event, |
7963 | NULL); | |
8d1b2d93 PZ |
7964 | } |
7965 | ||
82b89778 | 7966 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7967 | { |
9ee318a7 PZ |
7968 | struct perf_comm_event comm_event; |
7969 | ||
cdd6c482 | 7970 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7971 | return; |
a63eaf34 | 7972 | |
9ee318a7 | 7973 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7974 | .task = task, |
573402db PZ |
7975 | /* .comm */ |
7976 | /* .comm_size */ | |
cdd6c482 | 7977 | .event_id = { |
573402db | 7978 | .header = { |
cdd6c482 | 7979 | .type = PERF_RECORD_COMM, |
82b89778 | 7980 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7981 | /* .size */ |
7982 | }, | |
7983 | /* .pid */ | |
7984 | /* .tid */ | |
8d1b2d93 PZ |
7985 | }, |
7986 | }; | |
7987 | ||
cdd6c482 | 7988 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7989 | } |
7990 | ||
e4222673 HB |
7991 | /* |
7992 | * namespaces tracking | |
7993 | */ | |
7994 | ||
7995 | struct perf_namespaces_event { | |
7996 | struct task_struct *task; | |
7997 | ||
7998 | struct { | |
7999 | struct perf_event_header header; | |
8000 | ||
8001 | u32 pid; | |
8002 | u32 tid; | |
8003 | u64 nr_namespaces; | |
8004 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
8005 | } event_id; | |
8006 | }; | |
8007 | ||
8008 | static int perf_event_namespaces_match(struct perf_event *event) | |
8009 | { | |
8010 | return event->attr.namespaces; | |
8011 | } | |
8012 | ||
8013 | static void perf_event_namespaces_output(struct perf_event *event, | |
8014 | void *data) | |
8015 | { | |
8016 | struct perf_namespaces_event *namespaces_event = data; | |
8017 | struct perf_output_handle handle; | |
8018 | struct perf_sample_data sample; | |
34900ec5 | 8019 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
8020 | int ret; |
8021 | ||
8022 | if (!perf_event_namespaces_match(event)) | |
8023 | return; | |
8024 | ||
8025 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
8026 | &sample, event); | |
267fb273 | 8027 | ret = perf_output_begin(&handle, &sample, event, |
e4222673 HB |
8028 | namespaces_event->event_id.header.size); |
8029 | if (ret) | |
34900ec5 | 8030 | goto out; |
e4222673 HB |
8031 | |
8032 | namespaces_event->event_id.pid = perf_event_pid(event, | |
8033 | namespaces_event->task); | |
8034 | namespaces_event->event_id.tid = perf_event_tid(event, | |
8035 | namespaces_event->task); | |
8036 | ||
8037 | perf_output_put(&handle, namespaces_event->event_id); | |
8038 | ||
8039 | perf_event__output_id_sample(event, &handle, &sample); | |
8040 | ||
8041 | perf_output_end(&handle); | |
34900ec5 JO |
8042 | out: |
8043 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
8044 | } |
8045 | ||
8046 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
8047 | struct task_struct *task, | |
8048 | const struct proc_ns_operations *ns_ops) | |
8049 | { | |
8050 | struct path ns_path; | |
8051 | struct inode *ns_inode; | |
ce623f89 | 8052 | int error; |
e4222673 HB |
8053 | |
8054 | error = ns_get_path(&ns_path, task, ns_ops); | |
8055 | if (!error) { | |
8056 | ns_inode = ns_path.dentry->d_inode; | |
8057 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
8058 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 8059 | path_put(&ns_path); |
e4222673 HB |
8060 | } |
8061 | } | |
8062 | ||
8063 | void perf_event_namespaces(struct task_struct *task) | |
8064 | { | |
8065 | struct perf_namespaces_event namespaces_event; | |
8066 | struct perf_ns_link_info *ns_link_info; | |
8067 | ||
8068 | if (!atomic_read(&nr_namespaces_events)) | |
8069 | return; | |
8070 | ||
8071 | namespaces_event = (struct perf_namespaces_event){ | |
8072 | .task = task, | |
8073 | .event_id = { | |
8074 | .header = { | |
8075 | .type = PERF_RECORD_NAMESPACES, | |
8076 | .misc = 0, | |
8077 | .size = sizeof(namespaces_event.event_id), | |
8078 | }, | |
8079 | /* .pid */ | |
8080 | /* .tid */ | |
8081 | .nr_namespaces = NR_NAMESPACES, | |
8082 | /* .link_info[NR_NAMESPACES] */ | |
8083 | }, | |
8084 | }; | |
8085 | ||
8086 | ns_link_info = namespaces_event.event_id.link_info; | |
8087 | ||
8088 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
8089 | task, &mntns_operations); | |
8090 | ||
8091 | #ifdef CONFIG_USER_NS | |
8092 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
8093 | task, &userns_operations); | |
8094 | #endif | |
8095 | #ifdef CONFIG_NET_NS | |
8096 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
8097 | task, &netns_operations); | |
8098 | #endif | |
8099 | #ifdef CONFIG_UTS_NS | |
8100 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
8101 | task, &utsns_operations); | |
8102 | #endif | |
8103 | #ifdef CONFIG_IPC_NS | |
8104 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
8105 | task, &ipcns_operations); | |
8106 | #endif | |
8107 | #ifdef CONFIG_PID_NS | |
8108 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
8109 | task, &pidns_operations); | |
8110 | #endif | |
8111 | #ifdef CONFIG_CGROUPS | |
8112 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
8113 | task, &cgroupns_operations); | |
8114 | #endif | |
8115 | ||
8116 | perf_iterate_sb(perf_event_namespaces_output, | |
8117 | &namespaces_event, | |
8118 | NULL); | |
8119 | } | |
8120 | ||
96aaab68 NK |
8121 | /* |
8122 | * cgroup tracking | |
8123 | */ | |
8124 | #ifdef CONFIG_CGROUP_PERF | |
8125 | ||
8126 | struct perf_cgroup_event { | |
8127 | char *path; | |
8128 | int path_size; | |
8129 | struct { | |
8130 | struct perf_event_header header; | |
8131 | u64 id; | |
8132 | char path[]; | |
8133 | } event_id; | |
8134 | }; | |
8135 | ||
8136 | static int perf_event_cgroup_match(struct perf_event *event) | |
8137 | { | |
8138 | return event->attr.cgroup; | |
8139 | } | |
8140 | ||
8141 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
8142 | { | |
8143 | struct perf_cgroup_event *cgroup_event = data; | |
8144 | struct perf_output_handle handle; | |
8145 | struct perf_sample_data sample; | |
8146 | u16 header_size = cgroup_event->event_id.header.size; | |
8147 | int ret; | |
8148 | ||
8149 | if (!perf_event_cgroup_match(event)) | |
8150 | return; | |
8151 | ||
8152 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
8153 | &sample, event); | |
267fb273 | 8154 | ret = perf_output_begin(&handle, &sample, event, |
96aaab68 NK |
8155 | cgroup_event->event_id.header.size); |
8156 | if (ret) | |
8157 | goto out; | |
8158 | ||
8159 | perf_output_put(&handle, cgroup_event->event_id); | |
8160 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
8161 | ||
8162 | perf_event__output_id_sample(event, &handle, &sample); | |
8163 | ||
8164 | perf_output_end(&handle); | |
8165 | out: | |
8166 | cgroup_event->event_id.header.size = header_size; | |
8167 | } | |
8168 | ||
8169 | static void perf_event_cgroup(struct cgroup *cgrp) | |
8170 | { | |
8171 | struct perf_cgroup_event cgroup_event; | |
8172 | char path_enomem[16] = "//enomem"; | |
8173 | char *pathname; | |
8174 | size_t size; | |
8175 | ||
8176 | if (!atomic_read(&nr_cgroup_events)) | |
8177 | return; | |
8178 | ||
8179 | cgroup_event = (struct perf_cgroup_event){ | |
8180 | .event_id = { | |
8181 | .header = { | |
8182 | .type = PERF_RECORD_CGROUP, | |
8183 | .misc = 0, | |
8184 | .size = sizeof(cgroup_event.event_id), | |
8185 | }, | |
8186 | .id = cgroup_id(cgrp), | |
8187 | }, | |
8188 | }; | |
8189 | ||
8190 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
8191 | if (pathname == NULL) { | |
8192 | cgroup_event.path = path_enomem; | |
8193 | } else { | |
8194 | /* just to be sure to have enough space for alignment */ | |
8195 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
8196 | cgroup_event.path = pathname; | |
8197 | } | |
8198 | ||
8199 | /* | |
8200 | * Since our buffer works in 8 byte units we need to align our string | |
8201 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8202 | * zero'd out to avoid leaking random bits to userspace. | |
8203 | */ | |
8204 | size = strlen(cgroup_event.path) + 1; | |
8205 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8206 | cgroup_event.path[size++] = '\0'; | |
8207 | ||
8208 | cgroup_event.event_id.header.size += size; | |
8209 | cgroup_event.path_size = size; | |
8210 | ||
8211 | perf_iterate_sb(perf_event_cgroup_output, | |
8212 | &cgroup_event, | |
8213 | NULL); | |
8214 | ||
8215 | kfree(pathname); | |
8216 | } | |
8217 | ||
8218 | #endif | |
8219 | ||
0a4a9391 PZ |
8220 | /* |
8221 | * mmap tracking | |
8222 | */ | |
8223 | ||
8224 | struct perf_mmap_event { | |
089dd79d PZ |
8225 | struct vm_area_struct *vma; |
8226 | ||
8227 | const char *file_name; | |
8228 | int file_size; | |
13d7a241 SE |
8229 | int maj, min; |
8230 | u64 ino; | |
8231 | u64 ino_generation; | |
f972eb63 | 8232 | u32 prot, flags; |
88a16a13 JO |
8233 | u8 build_id[BUILD_ID_SIZE_MAX]; |
8234 | u32 build_id_size; | |
0a4a9391 PZ |
8235 | |
8236 | struct { | |
8237 | struct perf_event_header header; | |
8238 | ||
8239 | u32 pid; | |
8240 | u32 tid; | |
8241 | u64 start; | |
8242 | u64 len; | |
8243 | u64 pgoff; | |
cdd6c482 | 8244 | } event_id; |
0a4a9391 PZ |
8245 | }; |
8246 | ||
67516844 JO |
8247 | static int perf_event_mmap_match(struct perf_event *event, |
8248 | void *data) | |
8249 | { | |
8250 | struct perf_mmap_event *mmap_event = data; | |
8251 | struct vm_area_struct *vma = mmap_event->vma; | |
8252 | int executable = vma->vm_flags & VM_EXEC; | |
8253 | ||
8254 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 8255 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
8256 | } |
8257 | ||
cdd6c482 | 8258 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 8259 | void *data) |
0a4a9391 | 8260 | { |
52d857a8 | 8261 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 8262 | struct perf_output_handle handle; |
c980d109 | 8263 | struct perf_sample_data sample; |
cdd6c482 | 8264 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 8265 | u32 type = mmap_event->event_id.header.type; |
88a16a13 | 8266 | bool use_build_id; |
c980d109 | 8267 | int ret; |
0a4a9391 | 8268 | |
67516844 JO |
8269 | if (!perf_event_mmap_match(event, data)) |
8270 | return; | |
8271 | ||
13d7a241 SE |
8272 | if (event->attr.mmap2) { |
8273 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
8274 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
8275 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
8276 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 8277 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
8278 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
8279 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
8280 | } |
8281 | ||
c980d109 | 8282 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
267fb273 | 8283 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8284 | mmap_event->event_id.header.size); |
0a4a9391 | 8285 | if (ret) |
c980d109 | 8286 | goto out; |
0a4a9391 | 8287 | |
cdd6c482 IM |
8288 | mmap_event->event_id.pid = perf_event_pid(event, current); |
8289 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 8290 | |
88a16a13 JO |
8291 | use_build_id = event->attr.build_id && mmap_event->build_id_size; |
8292 | ||
8293 | if (event->attr.mmap2 && use_build_id) | |
8294 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID; | |
8295 | ||
cdd6c482 | 8296 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
8297 | |
8298 | if (event->attr.mmap2) { | |
88a16a13 JO |
8299 | if (use_build_id) { |
8300 | u8 size[4] = { (u8) mmap_event->build_id_size, 0, 0, 0 }; | |
8301 | ||
8302 | __output_copy(&handle, size, 4); | |
8303 | __output_copy(&handle, mmap_event->build_id, BUILD_ID_SIZE_MAX); | |
8304 | } else { | |
8305 | perf_output_put(&handle, mmap_event->maj); | |
8306 | perf_output_put(&handle, mmap_event->min); | |
8307 | perf_output_put(&handle, mmap_event->ino); | |
8308 | perf_output_put(&handle, mmap_event->ino_generation); | |
8309 | } | |
f972eb63 PZ |
8310 | perf_output_put(&handle, mmap_event->prot); |
8311 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
8312 | } |
8313 | ||
76369139 | 8314 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 8315 | mmap_event->file_size); |
c980d109 ACM |
8316 | |
8317 | perf_event__output_id_sample(event, &handle, &sample); | |
8318 | ||
78d613eb | 8319 | perf_output_end(&handle); |
c980d109 ACM |
8320 | out: |
8321 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 8322 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
8323 | } |
8324 | ||
cdd6c482 | 8325 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 8326 | { |
089dd79d PZ |
8327 | struct vm_area_struct *vma = mmap_event->vma; |
8328 | struct file *file = vma->vm_file; | |
13d7a241 SE |
8329 | int maj = 0, min = 0; |
8330 | u64 ino = 0, gen = 0; | |
f972eb63 | 8331 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
8332 | unsigned int size; |
8333 | char tmp[16]; | |
8334 | char *buf = NULL; | |
2c42cfbf | 8335 | char *name; |
413ee3b4 | 8336 | |
0b3589be PZ |
8337 | if (vma->vm_flags & VM_READ) |
8338 | prot |= PROT_READ; | |
8339 | if (vma->vm_flags & VM_WRITE) | |
8340 | prot |= PROT_WRITE; | |
8341 | if (vma->vm_flags & VM_EXEC) | |
8342 | prot |= PROT_EXEC; | |
8343 | ||
8344 | if (vma->vm_flags & VM_MAYSHARE) | |
8345 | flags = MAP_SHARED; | |
8346 | else | |
8347 | flags = MAP_PRIVATE; | |
8348 | ||
0b3589be PZ |
8349 | if (vma->vm_flags & VM_LOCKED) |
8350 | flags |= MAP_LOCKED; | |
03911132 | 8351 | if (is_vm_hugetlb_page(vma)) |
0b3589be PZ |
8352 | flags |= MAP_HUGETLB; |
8353 | ||
0a4a9391 | 8354 | if (file) { |
13d7a241 SE |
8355 | struct inode *inode; |
8356 | dev_t dev; | |
3ea2f2b9 | 8357 | |
2c42cfbf | 8358 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 8359 | if (!buf) { |
c7e548b4 ON |
8360 | name = "//enomem"; |
8361 | goto cpy_name; | |
0a4a9391 | 8362 | } |
413ee3b4 | 8363 | /* |
3ea2f2b9 | 8364 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
8365 | * need to add enough zero bytes after the string to handle |
8366 | * the 64bit alignment we do later. | |
8367 | */ | |
9bf39ab2 | 8368 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 8369 | if (IS_ERR(name)) { |
c7e548b4 ON |
8370 | name = "//toolong"; |
8371 | goto cpy_name; | |
0a4a9391 | 8372 | } |
13d7a241 SE |
8373 | inode = file_inode(vma->vm_file); |
8374 | dev = inode->i_sb->s_dev; | |
8375 | ino = inode->i_ino; | |
8376 | gen = inode->i_generation; | |
8377 | maj = MAJOR(dev); | |
8378 | min = MINOR(dev); | |
f972eb63 | 8379 | |
c7e548b4 | 8380 | goto got_name; |
0a4a9391 | 8381 | } else { |
fbe26abe JO |
8382 | if (vma->vm_ops && vma->vm_ops->name) { |
8383 | name = (char *) vma->vm_ops->name(vma); | |
8384 | if (name) | |
8385 | goto cpy_name; | |
8386 | } | |
8387 | ||
2c42cfbf | 8388 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8389 | if (name) |
8390 | goto cpy_name; | |
089dd79d | 8391 | |
32c5fb7e | 8392 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8393 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8394 | name = "[heap]"; |
8395 | goto cpy_name; | |
32c5fb7e ON |
8396 | } |
8397 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8398 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8399 | name = "[stack]"; |
8400 | goto cpy_name; | |
089dd79d PZ |
8401 | } |
8402 | ||
c7e548b4 ON |
8403 | name = "//anon"; |
8404 | goto cpy_name; | |
0a4a9391 PZ |
8405 | } |
8406 | ||
c7e548b4 ON |
8407 | cpy_name: |
8408 | strlcpy(tmp, name, sizeof(tmp)); | |
8409 | name = tmp; | |
0a4a9391 | 8410 | got_name: |
2c42cfbf PZ |
8411 | /* |
8412 | * Since our buffer works in 8 byte units we need to align our string | |
8413 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8414 | * zero'd out to avoid leaking random bits to userspace. | |
8415 | */ | |
8416 | size = strlen(name)+1; | |
8417 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8418 | name[size++] = '\0'; | |
0a4a9391 PZ |
8419 | |
8420 | mmap_event->file_name = name; | |
8421 | mmap_event->file_size = size; | |
13d7a241 SE |
8422 | mmap_event->maj = maj; |
8423 | mmap_event->min = min; | |
8424 | mmap_event->ino = ino; | |
8425 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8426 | mmap_event->prot = prot; |
8427 | mmap_event->flags = flags; | |
0a4a9391 | 8428 | |
2fe85427 SE |
8429 | if (!(vma->vm_flags & VM_EXEC)) |
8430 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8431 | ||
cdd6c482 | 8432 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8433 | |
88a16a13 JO |
8434 | if (atomic_read(&nr_build_id_events)) |
8435 | build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size); | |
8436 | ||
aab5b71e | 8437 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8438 | mmap_event, |
8439 | NULL); | |
665c2142 | 8440 | |
0a4a9391 PZ |
8441 | kfree(buf); |
8442 | } | |
8443 | ||
375637bc AS |
8444 | /* |
8445 | * Check whether inode and address range match filter criteria. | |
8446 | */ | |
8447 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8448 | struct file *file, unsigned long offset, | |
8449 | unsigned long size) | |
8450 | { | |
7f635ff1 MP |
8451 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8452 | if (!filter->path.dentry) | |
8453 | return false; | |
8454 | ||
9511bce9 | 8455 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8456 | return false; |
8457 | ||
8458 | if (filter->offset > offset + size) | |
8459 | return false; | |
8460 | ||
8461 | if (filter->offset + filter->size < offset) | |
8462 | return false; | |
8463 | ||
8464 | return true; | |
8465 | } | |
8466 | ||
c60f83b8 AS |
8467 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8468 | struct vm_area_struct *vma, | |
8469 | struct perf_addr_filter_range *fr) | |
8470 | { | |
8471 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8472 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8473 | struct file *file = vma->vm_file; | |
8474 | ||
8475 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8476 | return false; | |
8477 | ||
8478 | if (filter->offset < off) { | |
8479 | fr->start = vma->vm_start; | |
8480 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8481 | } else { | |
8482 | fr->start = vma->vm_start + filter->offset - off; | |
8483 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8484 | } | |
8485 | ||
8486 | return true; | |
8487 | } | |
8488 | ||
375637bc AS |
8489 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8490 | { | |
8491 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8492 | struct vm_area_struct *vma = data; | |
375637bc AS |
8493 | struct perf_addr_filter *filter; |
8494 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8495 | unsigned long flags; |
375637bc AS |
8496 | |
8497 | if (!has_addr_filter(event)) | |
8498 | return; | |
8499 | ||
c60f83b8 | 8500 | if (!vma->vm_file) |
375637bc AS |
8501 | return; |
8502 | ||
8503 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8504 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8505 | if (perf_addr_filter_vma_adjust(filter, vma, |
8506 | &event->addr_filter_ranges[count])) | |
375637bc | 8507 | restart++; |
375637bc AS |
8508 | |
8509 | count++; | |
8510 | } | |
8511 | ||
8512 | if (restart) | |
8513 | event->addr_filters_gen++; | |
8514 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8515 | ||
8516 | if (restart) | |
767ae086 | 8517 | perf_event_stop(event, 1); |
375637bc AS |
8518 | } |
8519 | ||
8520 | /* | |
8521 | * Adjust all task's events' filters to the new vma | |
8522 | */ | |
8523 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8524 | { | |
8525 | struct perf_event_context *ctx; | |
8526 | int ctxn; | |
8527 | ||
12b40a23 MP |
8528 | /* |
8529 | * Data tracing isn't supported yet and as such there is no need | |
8530 | * to keep track of anything that isn't related to executable code: | |
8531 | */ | |
8532 | if (!(vma->vm_flags & VM_EXEC)) | |
8533 | return; | |
8534 | ||
375637bc AS |
8535 | rcu_read_lock(); |
8536 | for_each_task_context_nr(ctxn) { | |
8537 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8538 | if (!ctx) | |
8539 | continue; | |
8540 | ||
aab5b71e | 8541 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8542 | } |
8543 | rcu_read_unlock(); | |
8544 | } | |
8545 | ||
3af9e859 | 8546 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8547 | { |
9ee318a7 PZ |
8548 | struct perf_mmap_event mmap_event; |
8549 | ||
cdd6c482 | 8550 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8551 | return; |
8552 | ||
8553 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8554 | .vma = vma, |
573402db PZ |
8555 | /* .file_name */ |
8556 | /* .file_size */ | |
cdd6c482 | 8557 | .event_id = { |
573402db | 8558 | .header = { |
cdd6c482 | 8559 | .type = PERF_RECORD_MMAP, |
39447b38 | 8560 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8561 | /* .size */ |
8562 | }, | |
8563 | /* .pid */ | |
8564 | /* .tid */ | |
089dd79d PZ |
8565 | .start = vma->vm_start, |
8566 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8567 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8568 | }, |
13d7a241 SE |
8569 | /* .maj (attr_mmap2 only) */ |
8570 | /* .min (attr_mmap2 only) */ | |
8571 | /* .ino (attr_mmap2 only) */ | |
8572 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8573 | /* .prot (attr_mmap2 only) */ |
8574 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8575 | }; |
8576 | ||
375637bc | 8577 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8578 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8579 | } |
8580 | ||
68db7e98 AS |
8581 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8582 | unsigned long size, u64 flags) | |
8583 | { | |
8584 | struct perf_output_handle handle; | |
8585 | struct perf_sample_data sample; | |
8586 | struct perf_aux_event { | |
8587 | struct perf_event_header header; | |
8588 | u64 offset; | |
8589 | u64 size; | |
8590 | u64 flags; | |
8591 | } rec = { | |
8592 | .header = { | |
8593 | .type = PERF_RECORD_AUX, | |
8594 | .misc = 0, | |
8595 | .size = sizeof(rec), | |
8596 | }, | |
8597 | .offset = head, | |
8598 | .size = size, | |
8599 | .flags = flags, | |
8600 | }; | |
8601 | int ret; | |
8602 | ||
8603 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8604 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
68db7e98 AS |
8605 | |
8606 | if (ret) | |
8607 | return; | |
8608 | ||
8609 | perf_output_put(&handle, rec); | |
8610 | perf_event__output_id_sample(event, &handle, &sample); | |
8611 | ||
8612 | perf_output_end(&handle); | |
8613 | } | |
8614 | ||
f38b0dbb KL |
8615 | /* |
8616 | * Lost/dropped samples logging | |
8617 | */ | |
8618 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8619 | { | |
8620 | struct perf_output_handle handle; | |
8621 | struct perf_sample_data sample; | |
8622 | int ret; | |
8623 | ||
8624 | struct { | |
8625 | struct perf_event_header header; | |
8626 | u64 lost; | |
8627 | } lost_samples_event = { | |
8628 | .header = { | |
8629 | .type = PERF_RECORD_LOST_SAMPLES, | |
8630 | .misc = 0, | |
8631 | .size = sizeof(lost_samples_event), | |
8632 | }, | |
8633 | .lost = lost, | |
8634 | }; | |
8635 | ||
8636 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8637 | ||
267fb273 | 8638 | ret = perf_output_begin(&handle, &sample, event, |
f38b0dbb KL |
8639 | lost_samples_event.header.size); |
8640 | if (ret) | |
8641 | return; | |
8642 | ||
8643 | perf_output_put(&handle, lost_samples_event); | |
8644 | perf_event__output_id_sample(event, &handle, &sample); | |
8645 | perf_output_end(&handle); | |
8646 | } | |
8647 | ||
45ac1403 AH |
8648 | /* |
8649 | * context_switch tracking | |
8650 | */ | |
8651 | ||
8652 | struct perf_switch_event { | |
8653 | struct task_struct *task; | |
8654 | struct task_struct *next_prev; | |
8655 | ||
8656 | struct { | |
8657 | struct perf_event_header header; | |
8658 | u32 next_prev_pid; | |
8659 | u32 next_prev_tid; | |
8660 | } event_id; | |
8661 | }; | |
8662 | ||
8663 | static int perf_event_switch_match(struct perf_event *event) | |
8664 | { | |
8665 | return event->attr.context_switch; | |
8666 | } | |
8667 | ||
8668 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8669 | { | |
8670 | struct perf_switch_event *se = data; | |
8671 | struct perf_output_handle handle; | |
8672 | struct perf_sample_data sample; | |
8673 | int ret; | |
8674 | ||
8675 | if (!perf_event_switch_match(event)) | |
8676 | return; | |
8677 | ||
8678 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8679 | if (event->ctx->task) { | |
8680 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8681 | se->event_id.header.size = sizeof(se->event_id.header); | |
8682 | } else { | |
8683 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8684 | se->event_id.header.size = sizeof(se->event_id); | |
8685 | se->event_id.next_prev_pid = | |
8686 | perf_event_pid(event, se->next_prev); | |
8687 | se->event_id.next_prev_tid = | |
8688 | perf_event_tid(event, se->next_prev); | |
8689 | } | |
8690 | ||
8691 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8692 | ||
267fb273 | 8693 | ret = perf_output_begin(&handle, &sample, event, se->event_id.header.size); |
45ac1403 AH |
8694 | if (ret) |
8695 | return; | |
8696 | ||
8697 | if (event->ctx->task) | |
8698 | perf_output_put(&handle, se->event_id.header); | |
8699 | else | |
8700 | perf_output_put(&handle, se->event_id); | |
8701 | ||
8702 | perf_event__output_id_sample(event, &handle, &sample); | |
8703 | ||
8704 | perf_output_end(&handle); | |
8705 | } | |
8706 | ||
8707 | static void perf_event_switch(struct task_struct *task, | |
8708 | struct task_struct *next_prev, bool sched_in) | |
8709 | { | |
8710 | struct perf_switch_event switch_event; | |
8711 | ||
8712 | /* N.B. caller checks nr_switch_events != 0 */ | |
8713 | ||
8714 | switch_event = (struct perf_switch_event){ | |
8715 | .task = task, | |
8716 | .next_prev = next_prev, | |
8717 | .event_id = { | |
8718 | .header = { | |
8719 | /* .type */ | |
8720 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8721 | /* .size */ | |
8722 | }, | |
8723 | /* .next_prev_pid */ | |
8724 | /* .next_prev_tid */ | |
8725 | }, | |
8726 | }; | |
8727 | ||
3ba9f93b | 8728 | if (!sched_in && task->on_rq) { |
101592b4 AB |
8729 | switch_event.event_id.header.misc |= |
8730 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
3ba9f93b | 8731 | } |
101592b4 | 8732 | |
3ba9f93b | 8733 | perf_iterate_sb(perf_event_switch_output, &switch_event, NULL); |
45ac1403 AH |
8734 | } |
8735 | ||
a78ac325 PZ |
8736 | /* |
8737 | * IRQ throttle logging | |
8738 | */ | |
8739 | ||
cdd6c482 | 8740 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8741 | { |
8742 | struct perf_output_handle handle; | |
c980d109 | 8743 | struct perf_sample_data sample; |
a78ac325 PZ |
8744 | int ret; |
8745 | ||
8746 | struct { | |
8747 | struct perf_event_header header; | |
8748 | u64 time; | |
cca3f454 | 8749 | u64 id; |
7f453c24 | 8750 | u64 stream_id; |
a78ac325 PZ |
8751 | } throttle_event = { |
8752 | .header = { | |
cdd6c482 | 8753 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8754 | .misc = 0, |
8755 | .size = sizeof(throttle_event), | |
8756 | }, | |
34f43927 | 8757 | .time = perf_event_clock(event), |
cdd6c482 IM |
8758 | .id = primary_event_id(event), |
8759 | .stream_id = event->id, | |
a78ac325 PZ |
8760 | }; |
8761 | ||
966ee4d6 | 8762 | if (enable) |
cdd6c482 | 8763 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8764 | |
c980d109 ACM |
8765 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8766 | ||
267fb273 | 8767 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8768 | throttle_event.header.size); |
a78ac325 PZ |
8769 | if (ret) |
8770 | return; | |
8771 | ||
8772 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8773 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8774 | perf_output_end(&handle); |
8775 | } | |
8776 | ||
76193a94 SL |
8777 | /* |
8778 | * ksymbol register/unregister tracking | |
8779 | */ | |
8780 | ||
8781 | struct perf_ksymbol_event { | |
8782 | const char *name; | |
8783 | int name_len; | |
8784 | struct { | |
8785 | struct perf_event_header header; | |
8786 | u64 addr; | |
8787 | u32 len; | |
8788 | u16 ksym_type; | |
8789 | u16 flags; | |
8790 | } event_id; | |
8791 | }; | |
8792 | ||
8793 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8794 | { | |
8795 | return event->attr.ksymbol; | |
8796 | } | |
8797 | ||
8798 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8799 | { | |
8800 | struct perf_ksymbol_event *ksymbol_event = data; | |
8801 | struct perf_output_handle handle; | |
8802 | struct perf_sample_data sample; | |
8803 | int ret; | |
8804 | ||
8805 | if (!perf_event_ksymbol_match(event)) | |
8806 | return; | |
8807 | ||
8808 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8809 | &sample, event); | |
267fb273 | 8810 | ret = perf_output_begin(&handle, &sample, event, |
76193a94 SL |
8811 | ksymbol_event->event_id.header.size); |
8812 | if (ret) | |
8813 | return; | |
8814 | ||
8815 | perf_output_put(&handle, ksymbol_event->event_id); | |
8816 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8817 | perf_event__output_id_sample(event, &handle, &sample); | |
8818 | ||
8819 | perf_output_end(&handle); | |
8820 | } | |
8821 | ||
8822 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8823 | const char *sym) | |
8824 | { | |
8825 | struct perf_ksymbol_event ksymbol_event; | |
8826 | char name[KSYM_NAME_LEN]; | |
8827 | u16 flags = 0; | |
8828 | int name_len; | |
8829 | ||
8830 | if (!atomic_read(&nr_ksymbol_events)) | |
8831 | return; | |
8832 | ||
8833 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8834 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8835 | goto err; | |
8836 | ||
8837 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8838 | name_len = strlen(name) + 1; | |
8839 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8840 | name[name_len++] = '\0'; | |
8841 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8842 | ||
8843 | if (unregister) | |
8844 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8845 | ||
8846 | ksymbol_event = (struct perf_ksymbol_event){ | |
8847 | .name = name, | |
8848 | .name_len = name_len, | |
8849 | .event_id = { | |
8850 | .header = { | |
8851 | .type = PERF_RECORD_KSYMBOL, | |
8852 | .size = sizeof(ksymbol_event.event_id) + | |
8853 | name_len, | |
8854 | }, | |
8855 | .addr = addr, | |
8856 | .len = len, | |
8857 | .ksym_type = ksym_type, | |
8858 | .flags = flags, | |
8859 | }, | |
8860 | }; | |
8861 | ||
8862 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8863 | return; | |
8864 | err: | |
8865 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8866 | } | |
8867 | ||
6ee52e2a SL |
8868 | /* |
8869 | * bpf program load/unload tracking | |
8870 | */ | |
8871 | ||
8872 | struct perf_bpf_event { | |
8873 | struct bpf_prog *prog; | |
8874 | struct { | |
8875 | struct perf_event_header header; | |
8876 | u16 type; | |
8877 | u16 flags; | |
8878 | u32 id; | |
8879 | u8 tag[BPF_TAG_SIZE]; | |
8880 | } event_id; | |
8881 | }; | |
8882 | ||
8883 | static int perf_event_bpf_match(struct perf_event *event) | |
8884 | { | |
8885 | return event->attr.bpf_event; | |
8886 | } | |
8887 | ||
8888 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8889 | { | |
8890 | struct perf_bpf_event *bpf_event = data; | |
8891 | struct perf_output_handle handle; | |
8892 | struct perf_sample_data sample; | |
8893 | int ret; | |
8894 | ||
8895 | if (!perf_event_bpf_match(event)) | |
8896 | return; | |
8897 | ||
8898 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8899 | &sample, event); | |
267fb273 | 8900 | ret = perf_output_begin(&handle, data, event, |
6ee52e2a SL |
8901 | bpf_event->event_id.header.size); |
8902 | if (ret) | |
8903 | return; | |
8904 | ||
8905 | perf_output_put(&handle, bpf_event->event_id); | |
8906 | perf_event__output_id_sample(event, &handle, &sample); | |
8907 | ||
8908 | perf_output_end(&handle); | |
8909 | } | |
8910 | ||
8911 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8912 | enum perf_bpf_event_type type) | |
8913 | { | |
8914 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8915 | int i; |
8916 | ||
8917 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8918 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8919 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8920 | prog->jited_len, unregister, |
8921 | prog->aux->ksym.name); | |
6ee52e2a SL |
8922 | } else { |
8923 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8924 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8925 | ||
6ee52e2a SL |
8926 | perf_event_ksymbol( |
8927 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8928 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8929 | subprog->jited_len, unregister, |
8930 | prog->aux->ksym.name); | |
6ee52e2a SL |
8931 | } |
8932 | } | |
8933 | } | |
8934 | ||
8935 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8936 | enum perf_bpf_event_type type, | |
8937 | u16 flags) | |
8938 | { | |
8939 | struct perf_bpf_event bpf_event; | |
8940 | ||
8941 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8942 | type >= PERF_BPF_EVENT_MAX) | |
8943 | return; | |
8944 | ||
8945 | switch (type) { | |
8946 | case PERF_BPF_EVENT_PROG_LOAD: | |
8947 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8948 | if (atomic_read(&nr_ksymbol_events)) | |
8949 | perf_event_bpf_emit_ksymbols(prog, type); | |
8950 | break; | |
8951 | default: | |
8952 | break; | |
8953 | } | |
8954 | ||
8955 | if (!atomic_read(&nr_bpf_events)) | |
8956 | return; | |
8957 | ||
8958 | bpf_event = (struct perf_bpf_event){ | |
8959 | .prog = prog, | |
8960 | .event_id = { | |
8961 | .header = { | |
8962 | .type = PERF_RECORD_BPF_EVENT, | |
8963 | .size = sizeof(bpf_event.event_id), | |
8964 | }, | |
8965 | .type = type, | |
8966 | .flags = flags, | |
8967 | .id = prog->aux->id, | |
8968 | }, | |
8969 | }; | |
8970 | ||
8971 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8972 | ||
8973 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8974 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8975 | } | |
8976 | ||
e17d43b9 AH |
8977 | struct perf_text_poke_event { |
8978 | const void *old_bytes; | |
8979 | const void *new_bytes; | |
8980 | size_t pad; | |
8981 | u16 old_len; | |
8982 | u16 new_len; | |
8983 | ||
8984 | struct { | |
8985 | struct perf_event_header header; | |
8986 | ||
8987 | u64 addr; | |
8988 | } event_id; | |
8989 | }; | |
8990 | ||
8991 | static int perf_event_text_poke_match(struct perf_event *event) | |
8992 | { | |
8993 | return event->attr.text_poke; | |
8994 | } | |
8995 | ||
8996 | static void perf_event_text_poke_output(struct perf_event *event, void *data) | |
8997 | { | |
8998 | struct perf_text_poke_event *text_poke_event = data; | |
8999 | struct perf_output_handle handle; | |
9000 | struct perf_sample_data sample; | |
9001 | u64 padding = 0; | |
9002 | int ret; | |
9003 | ||
9004 | if (!perf_event_text_poke_match(event)) | |
9005 | return; | |
9006 | ||
9007 | perf_event_header__init_id(&text_poke_event->event_id.header, &sample, event); | |
9008 | ||
267fb273 PZ |
9009 | ret = perf_output_begin(&handle, &sample, event, |
9010 | text_poke_event->event_id.header.size); | |
e17d43b9 AH |
9011 | if (ret) |
9012 | return; | |
9013 | ||
9014 | perf_output_put(&handle, text_poke_event->event_id); | |
9015 | perf_output_put(&handle, text_poke_event->old_len); | |
9016 | perf_output_put(&handle, text_poke_event->new_len); | |
9017 | ||
9018 | __output_copy(&handle, text_poke_event->old_bytes, text_poke_event->old_len); | |
9019 | __output_copy(&handle, text_poke_event->new_bytes, text_poke_event->new_len); | |
9020 | ||
9021 | if (text_poke_event->pad) | |
9022 | __output_copy(&handle, &padding, text_poke_event->pad); | |
9023 | ||
9024 | perf_event__output_id_sample(event, &handle, &sample); | |
9025 | ||
9026 | perf_output_end(&handle); | |
9027 | } | |
9028 | ||
9029 | void perf_event_text_poke(const void *addr, const void *old_bytes, | |
9030 | size_t old_len, const void *new_bytes, size_t new_len) | |
9031 | { | |
9032 | struct perf_text_poke_event text_poke_event; | |
9033 | size_t tot, pad; | |
9034 | ||
9035 | if (!atomic_read(&nr_text_poke_events)) | |
9036 | return; | |
9037 | ||
9038 | tot = sizeof(text_poke_event.old_len) + old_len; | |
9039 | tot += sizeof(text_poke_event.new_len) + new_len; | |
9040 | pad = ALIGN(tot, sizeof(u64)) - tot; | |
9041 | ||
9042 | text_poke_event = (struct perf_text_poke_event){ | |
9043 | .old_bytes = old_bytes, | |
9044 | .new_bytes = new_bytes, | |
9045 | .pad = pad, | |
9046 | .old_len = old_len, | |
9047 | .new_len = new_len, | |
9048 | .event_id = { | |
9049 | .header = { | |
9050 | .type = PERF_RECORD_TEXT_POKE, | |
9051 | .misc = PERF_RECORD_MISC_KERNEL, | |
9052 | .size = sizeof(text_poke_event.event_id) + tot + pad, | |
9053 | }, | |
9054 | .addr = (unsigned long)addr, | |
9055 | }, | |
9056 | }; | |
9057 | ||
9058 | perf_iterate_sb(perf_event_text_poke_output, &text_poke_event, NULL); | |
9059 | } | |
9060 | ||
8d4e6c4c AS |
9061 | void perf_event_itrace_started(struct perf_event *event) |
9062 | { | |
9063 | event->attach_state |= PERF_ATTACH_ITRACE; | |
9064 | } | |
9065 | ||
ec0d7729 AS |
9066 | static void perf_log_itrace_start(struct perf_event *event) |
9067 | { | |
9068 | struct perf_output_handle handle; | |
9069 | struct perf_sample_data sample; | |
9070 | struct perf_aux_event { | |
9071 | struct perf_event_header header; | |
9072 | u32 pid; | |
9073 | u32 tid; | |
9074 | } rec; | |
9075 | int ret; | |
9076 | ||
9077 | if (event->parent) | |
9078 | event = event->parent; | |
9079 | ||
9080 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 9081 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
9082 | return; |
9083 | ||
ec0d7729 AS |
9084 | rec.header.type = PERF_RECORD_ITRACE_START; |
9085 | rec.header.misc = 0; | |
9086 | rec.header.size = sizeof(rec); | |
9087 | rec.pid = perf_event_pid(event, current); | |
9088 | rec.tid = perf_event_tid(event, current); | |
9089 | ||
9090 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 9091 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
ec0d7729 AS |
9092 | |
9093 | if (ret) | |
9094 | return; | |
9095 | ||
9096 | perf_output_put(&handle, rec); | |
9097 | perf_event__output_id_sample(event, &handle, &sample); | |
9098 | ||
9099 | perf_output_end(&handle); | |
9100 | } | |
9101 | ||
475113d9 JO |
9102 | static int |
9103 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 9104 | { |
cdd6c482 | 9105 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 9106 | int ret = 0; |
475113d9 | 9107 | u64 seq; |
96398826 | 9108 | |
e050e3f0 SE |
9109 | seq = __this_cpu_read(perf_throttled_seq); |
9110 | if (seq != hwc->interrupts_seq) { | |
9111 | hwc->interrupts_seq = seq; | |
9112 | hwc->interrupts = 1; | |
9113 | } else { | |
9114 | hwc->interrupts++; | |
9115 | if (unlikely(throttle | |
9116 | && hwc->interrupts >= max_samples_per_tick)) { | |
9117 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 9118 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
9119 | hwc->interrupts = MAX_INTERRUPTS; |
9120 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
9121 | ret = 1; |
9122 | } | |
e050e3f0 | 9123 | } |
60db5e09 | 9124 | |
cdd6c482 | 9125 | if (event->attr.freq) { |
def0a9b2 | 9126 | u64 now = perf_clock(); |
abd50713 | 9127 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 9128 | |
abd50713 | 9129 | hwc->freq_time_stamp = now; |
bd2b5b12 | 9130 | |
abd50713 | 9131 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 9132 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
9133 | } |
9134 | ||
475113d9 JO |
9135 | return ret; |
9136 | } | |
9137 | ||
9138 | int perf_event_account_interrupt(struct perf_event *event) | |
9139 | { | |
9140 | return __perf_event_account_interrupt(event, 1); | |
9141 | } | |
9142 | ||
9143 | /* | |
9144 | * Generic event overflow handling, sampling. | |
9145 | */ | |
9146 | ||
9147 | static int __perf_event_overflow(struct perf_event *event, | |
9148 | int throttle, struct perf_sample_data *data, | |
9149 | struct pt_regs *regs) | |
9150 | { | |
9151 | int events = atomic_read(&event->event_limit); | |
9152 | int ret = 0; | |
9153 | ||
9154 | /* | |
9155 | * Non-sampling counters might still use the PMI to fold short | |
9156 | * hardware counters, ignore those. | |
9157 | */ | |
9158 | if (unlikely(!is_sampling_event(event))) | |
9159 | return 0; | |
9160 | ||
9161 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 9162 | |
2023b359 PZ |
9163 | /* |
9164 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 9165 | * events |
2023b359 PZ |
9166 | */ |
9167 | ||
cdd6c482 IM |
9168 | event->pending_kill = POLL_IN; |
9169 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 9170 | ret = 1; |
cdd6c482 | 9171 | event->pending_kill = POLL_HUP; |
97ba62b2 | 9172 | event->pending_addr = data->addr; |
5aab90ce JO |
9173 | |
9174 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
9175 | } |
9176 | ||
aa6a5f3c | 9177 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 9178 | |
fed66e2c | 9179 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
9180 | event->pending_wakeup = 1; |
9181 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
9182 | } |
9183 | ||
79f14641 | 9184 | return ret; |
f6c7d5fe PZ |
9185 | } |
9186 | ||
a8b0ca17 | 9187 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
9188 | struct perf_sample_data *data, |
9189 | struct pt_regs *regs) | |
850bc73f | 9190 | { |
a8b0ca17 | 9191 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
9192 | } |
9193 | ||
15dbf27c | 9194 | /* |
cdd6c482 | 9195 | * Generic software event infrastructure |
15dbf27c PZ |
9196 | */ |
9197 | ||
b28ab83c PZ |
9198 | struct swevent_htable { |
9199 | struct swevent_hlist *swevent_hlist; | |
9200 | struct mutex hlist_mutex; | |
9201 | int hlist_refcount; | |
9202 | ||
9203 | /* Recursion avoidance in each contexts */ | |
9204 | int recursion[PERF_NR_CONTEXTS]; | |
9205 | }; | |
9206 | ||
9207 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
9208 | ||
7b4b6658 | 9209 | /* |
cdd6c482 IM |
9210 | * We directly increment event->count and keep a second value in |
9211 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
9212 | * is kept in the range [-sample_period, 0] so that we can use the |
9213 | * sign as trigger. | |
9214 | */ | |
9215 | ||
ab573844 | 9216 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 9217 | { |
cdd6c482 | 9218 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
9219 | u64 period = hwc->last_period; |
9220 | u64 nr, offset; | |
9221 | s64 old, val; | |
9222 | ||
9223 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
9224 | |
9225 | again: | |
e7850595 | 9226 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
9227 | if (val < 0) |
9228 | return 0; | |
15dbf27c | 9229 | |
7b4b6658 PZ |
9230 | nr = div64_u64(period + val, period); |
9231 | offset = nr * period; | |
9232 | val -= offset; | |
e7850595 | 9233 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 9234 | goto again; |
15dbf27c | 9235 | |
7b4b6658 | 9236 | return nr; |
15dbf27c PZ |
9237 | } |
9238 | ||
0cff784a | 9239 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 9240 | struct perf_sample_data *data, |
5622f295 | 9241 | struct pt_regs *regs) |
15dbf27c | 9242 | { |
cdd6c482 | 9243 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 9244 | int throttle = 0; |
15dbf27c | 9245 | |
0cff784a PZ |
9246 | if (!overflow) |
9247 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 9248 | |
7b4b6658 PZ |
9249 | if (hwc->interrupts == MAX_INTERRUPTS) |
9250 | return; | |
15dbf27c | 9251 | |
7b4b6658 | 9252 | for (; overflow; overflow--) { |
a8b0ca17 | 9253 | if (__perf_event_overflow(event, throttle, |
5622f295 | 9254 | data, regs)) { |
7b4b6658 PZ |
9255 | /* |
9256 | * We inhibit the overflow from happening when | |
9257 | * hwc->interrupts == MAX_INTERRUPTS. | |
9258 | */ | |
9259 | break; | |
9260 | } | |
cf450a73 | 9261 | throttle = 1; |
7b4b6658 | 9262 | } |
15dbf27c PZ |
9263 | } |
9264 | ||
a4eaf7f1 | 9265 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 9266 | struct perf_sample_data *data, |
5622f295 | 9267 | struct pt_regs *regs) |
7b4b6658 | 9268 | { |
cdd6c482 | 9269 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 9270 | |
e7850595 | 9271 | local64_add(nr, &event->count); |
d6d020e9 | 9272 | |
0cff784a PZ |
9273 | if (!regs) |
9274 | return; | |
9275 | ||
6c7e550f | 9276 | if (!is_sampling_event(event)) |
7b4b6658 | 9277 | return; |
d6d020e9 | 9278 | |
5d81e5cf AV |
9279 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
9280 | data->period = nr; | |
9281 | return perf_swevent_overflow(event, 1, data, regs); | |
9282 | } else | |
9283 | data->period = event->hw.last_period; | |
9284 | ||
0cff784a | 9285 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 9286 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 9287 | |
e7850595 | 9288 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 9289 | return; |
df1a132b | 9290 | |
a8b0ca17 | 9291 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
9292 | } |
9293 | ||
f5ffe02e FW |
9294 | static int perf_exclude_event(struct perf_event *event, |
9295 | struct pt_regs *regs) | |
9296 | { | |
a4eaf7f1 | 9297 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 9298 | return 1; |
a4eaf7f1 | 9299 | |
f5ffe02e FW |
9300 | if (regs) { |
9301 | if (event->attr.exclude_user && user_mode(regs)) | |
9302 | return 1; | |
9303 | ||
9304 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
9305 | return 1; | |
9306 | } | |
9307 | ||
9308 | return 0; | |
9309 | } | |
9310 | ||
cdd6c482 | 9311 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 9312 | enum perf_type_id type, |
6fb2915d LZ |
9313 | u32 event_id, |
9314 | struct perf_sample_data *data, | |
9315 | struct pt_regs *regs) | |
15dbf27c | 9316 | { |
cdd6c482 | 9317 | if (event->attr.type != type) |
a21ca2ca | 9318 | return 0; |
f5ffe02e | 9319 | |
cdd6c482 | 9320 | if (event->attr.config != event_id) |
15dbf27c PZ |
9321 | return 0; |
9322 | ||
f5ffe02e FW |
9323 | if (perf_exclude_event(event, regs)) |
9324 | return 0; | |
15dbf27c PZ |
9325 | |
9326 | return 1; | |
9327 | } | |
9328 | ||
76e1d904 FW |
9329 | static inline u64 swevent_hash(u64 type, u32 event_id) |
9330 | { | |
9331 | u64 val = event_id | (type << 32); | |
9332 | ||
9333 | return hash_64(val, SWEVENT_HLIST_BITS); | |
9334 | } | |
9335 | ||
49f135ed FW |
9336 | static inline struct hlist_head * |
9337 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 9338 | { |
49f135ed FW |
9339 | u64 hash = swevent_hash(type, event_id); |
9340 | ||
9341 | return &hlist->heads[hash]; | |
9342 | } | |
76e1d904 | 9343 | |
49f135ed FW |
9344 | /* For the read side: events when they trigger */ |
9345 | static inline struct hlist_head * | |
b28ab83c | 9346 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
9347 | { |
9348 | struct swevent_hlist *hlist; | |
76e1d904 | 9349 | |
b28ab83c | 9350 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
9351 | if (!hlist) |
9352 | return NULL; | |
9353 | ||
49f135ed FW |
9354 | return __find_swevent_head(hlist, type, event_id); |
9355 | } | |
9356 | ||
9357 | /* For the event head insertion and removal in the hlist */ | |
9358 | static inline struct hlist_head * | |
b28ab83c | 9359 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
9360 | { |
9361 | struct swevent_hlist *hlist; | |
9362 | u32 event_id = event->attr.config; | |
9363 | u64 type = event->attr.type; | |
9364 | ||
9365 | /* | |
9366 | * Event scheduling is always serialized against hlist allocation | |
9367 | * and release. Which makes the protected version suitable here. | |
9368 | * The context lock guarantees that. | |
9369 | */ | |
b28ab83c | 9370 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
9371 | lockdep_is_held(&event->ctx->lock)); |
9372 | if (!hlist) | |
9373 | return NULL; | |
9374 | ||
9375 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
9376 | } |
9377 | ||
9378 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 9379 | u64 nr, |
76e1d904 FW |
9380 | struct perf_sample_data *data, |
9381 | struct pt_regs *regs) | |
15dbf27c | 9382 | { |
4a32fea9 | 9383 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9384 | struct perf_event *event; |
76e1d904 | 9385 | struct hlist_head *head; |
15dbf27c | 9386 | |
76e1d904 | 9387 | rcu_read_lock(); |
b28ab83c | 9388 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
9389 | if (!head) |
9390 | goto end; | |
9391 | ||
b67bfe0d | 9392 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 9393 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 9394 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 9395 | } |
76e1d904 FW |
9396 | end: |
9397 | rcu_read_unlock(); | |
15dbf27c PZ |
9398 | } |
9399 | ||
86038c5e PZI |
9400 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
9401 | ||
4ed7c92d | 9402 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 9403 | { |
4a32fea9 | 9404 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 9405 | |
b28ab83c | 9406 | return get_recursion_context(swhash->recursion); |
96f6d444 | 9407 | } |
645e8cc0 | 9408 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 9409 | |
98b5c2c6 | 9410 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 9411 | { |
4a32fea9 | 9412 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 9413 | |
b28ab83c | 9414 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 9415 | } |
15dbf27c | 9416 | |
86038c5e | 9417 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 9418 | { |
a4234bfc | 9419 | struct perf_sample_data data; |
4ed7c92d | 9420 | |
86038c5e | 9421 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 9422 | return; |
a4234bfc | 9423 | |
fd0d000b | 9424 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 9425 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
9426 | } |
9427 | ||
9428 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
9429 | { | |
9430 | int rctx; | |
9431 | ||
9432 | preempt_disable_notrace(); | |
9433 | rctx = perf_swevent_get_recursion_context(); | |
9434 | if (unlikely(rctx < 0)) | |
9435 | goto fail; | |
9436 | ||
9437 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
9438 | |
9439 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 9440 | fail: |
1c024eca | 9441 | preempt_enable_notrace(); |
b8e83514 PZ |
9442 | } |
9443 | ||
cdd6c482 | 9444 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 9445 | { |
15dbf27c PZ |
9446 | } |
9447 | ||
a4eaf7f1 | 9448 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 9449 | { |
4a32fea9 | 9450 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9451 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
9452 | struct hlist_head *head; |
9453 | ||
6c7e550f | 9454 | if (is_sampling_event(event)) { |
7b4b6658 | 9455 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 9456 | perf_swevent_set_period(event); |
7b4b6658 | 9457 | } |
76e1d904 | 9458 | |
a4eaf7f1 PZ |
9459 | hwc->state = !(flags & PERF_EF_START); |
9460 | ||
b28ab83c | 9461 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9462 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9463 | return -EINVAL; |
9464 | ||
9465 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9466 | perf_event_update_userpage(event); |
76e1d904 | 9467 | |
15dbf27c PZ |
9468 | return 0; |
9469 | } | |
9470 | ||
a4eaf7f1 | 9471 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9472 | { |
76e1d904 | 9473 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9474 | } |
9475 | ||
a4eaf7f1 | 9476 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9477 | { |
a4eaf7f1 | 9478 | event->hw.state = 0; |
d6d020e9 | 9479 | } |
aa9c4c0f | 9480 | |
a4eaf7f1 | 9481 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9482 | { |
a4eaf7f1 | 9483 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9484 | } |
9485 | ||
49f135ed FW |
9486 | /* Deref the hlist from the update side */ |
9487 | static inline struct swevent_hlist * | |
b28ab83c | 9488 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9489 | { |
b28ab83c PZ |
9490 | return rcu_dereference_protected(swhash->swevent_hlist, |
9491 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9492 | } |
9493 | ||
b28ab83c | 9494 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9495 | { |
b28ab83c | 9496 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9497 | |
49f135ed | 9498 | if (!hlist) |
76e1d904 FW |
9499 | return; |
9500 | ||
70691d4a | 9501 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9502 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9503 | } |
9504 | ||
3b364d7b | 9505 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9506 | { |
b28ab83c | 9507 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9508 | |
b28ab83c | 9509 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9510 | |
b28ab83c PZ |
9511 | if (!--swhash->hlist_refcount) |
9512 | swevent_hlist_release(swhash); | |
76e1d904 | 9513 | |
b28ab83c | 9514 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9515 | } |
9516 | ||
3b364d7b | 9517 | static void swevent_hlist_put(void) |
76e1d904 FW |
9518 | { |
9519 | int cpu; | |
9520 | ||
76e1d904 | 9521 | for_each_possible_cpu(cpu) |
3b364d7b | 9522 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9523 | } |
9524 | ||
3b364d7b | 9525 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9526 | { |
b28ab83c | 9527 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9528 | int err = 0; |
9529 | ||
b28ab83c | 9530 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9531 | if (!swevent_hlist_deref(swhash) && |
9532 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9533 | struct swevent_hlist *hlist; |
9534 | ||
9535 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9536 | if (!hlist) { | |
9537 | err = -ENOMEM; | |
9538 | goto exit; | |
9539 | } | |
b28ab83c | 9540 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9541 | } |
b28ab83c | 9542 | swhash->hlist_refcount++; |
9ed6060d | 9543 | exit: |
b28ab83c | 9544 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9545 | |
9546 | return err; | |
9547 | } | |
9548 | ||
3b364d7b | 9549 | static int swevent_hlist_get(void) |
76e1d904 | 9550 | { |
3b364d7b | 9551 | int err, cpu, failed_cpu; |
76e1d904 | 9552 | |
a63fbed7 | 9553 | mutex_lock(&pmus_lock); |
76e1d904 | 9554 | for_each_possible_cpu(cpu) { |
3b364d7b | 9555 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9556 | if (err) { |
9557 | failed_cpu = cpu; | |
9558 | goto fail; | |
9559 | } | |
9560 | } | |
a63fbed7 | 9561 | mutex_unlock(&pmus_lock); |
76e1d904 | 9562 | return 0; |
9ed6060d | 9563 | fail: |
76e1d904 FW |
9564 | for_each_possible_cpu(cpu) { |
9565 | if (cpu == failed_cpu) | |
9566 | break; | |
3b364d7b | 9567 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9568 | } |
a63fbed7 | 9569 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9570 | return err; |
9571 | } | |
9572 | ||
c5905afb | 9573 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9574 | |
b0a873eb PZ |
9575 | static void sw_perf_event_destroy(struct perf_event *event) |
9576 | { | |
9577 | u64 event_id = event->attr.config; | |
95476b64 | 9578 | |
b0a873eb PZ |
9579 | WARN_ON(event->parent); |
9580 | ||
c5905afb | 9581 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9582 | swevent_hlist_put(); |
b0a873eb PZ |
9583 | } |
9584 | ||
9585 | static int perf_swevent_init(struct perf_event *event) | |
9586 | { | |
8176cced | 9587 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9588 | |
9589 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9590 | return -ENOENT; | |
9591 | ||
2481c5fa SE |
9592 | /* |
9593 | * no branch sampling for software events | |
9594 | */ | |
9595 | if (has_branch_stack(event)) | |
9596 | return -EOPNOTSUPP; | |
9597 | ||
b0a873eb PZ |
9598 | switch (event_id) { |
9599 | case PERF_COUNT_SW_CPU_CLOCK: | |
9600 | case PERF_COUNT_SW_TASK_CLOCK: | |
9601 | return -ENOENT; | |
9602 | ||
9603 | default: | |
9604 | break; | |
9605 | } | |
9606 | ||
ce677831 | 9607 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9608 | return -ENOENT; |
9609 | ||
9610 | if (!event->parent) { | |
9611 | int err; | |
9612 | ||
3b364d7b | 9613 | err = swevent_hlist_get(); |
b0a873eb PZ |
9614 | if (err) |
9615 | return err; | |
9616 | ||
c5905afb | 9617 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9618 | event->destroy = sw_perf_event_destroy; |
9619 | } | |
9620 | ||
9621 | return 0; | |
9622 | } | |
9623 | ||
9624 | static struct pmu perf_swevent = { | |
89a1e187 | 9625 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9626 | |
34f43927 PZ |
9627 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9628 | ||
b0a873eb | 9629 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9630 | .add = perf_swevent_add, |
9631 | .del = perf_swevent_del, | |
9632 | .start = perf_swevent_start, | |
9633 | .stop = perf_swevent_stop, | |
1c024eca | 9634 | .read = perf_swevent_read, |
1c024eca PZ |
9635 | }; |
9636 | ||
b0a873eb PZ |
9637 | #ifdef CONFIG_EVENT_TRACING |
9638 | ||
1c024eca PZ |
9639 | static int perf_tp_filter_match(struct perf_event *event, |
9640 | struct perf_sample_data *data) | |
9641 | { | |
7e3f977e | 9642 | void *record = data->raw->frag.data; |
1c024eca | 9643 | |
b71b437e PZ |
9644 | /* only top level events have filters set */ |
9645 | if (event->parent) | |
9646 | event = event->parent; | |
9647 | ||
1c024eca PZ |
9648 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9649 | return 1; | |
9650 | return 0; | |
9651 | } | |
9652 | ||
9653 | static int perf_tp_event_match(struct perf_event *event, | |
9654 | struct perf_sample_data *data, | |
9655 | struct pt_regs *regs) | |
9656 | { | |
a0f7d0f7 FW |
9657 | if (event->hw.state & PERF_HES_STOPPED) |
9658 | return 0; | |
580d607c | 9659 | /* |
9fd2e48b | 9660 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9661 | */ |
9fd2e48b | 9662 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9663 | return 0; |
9664 | ||
9665 | if (!perf_tp_filter_match(event, data)) | |
9666 | return 0; | |
9667 | ||
9668 | return 1; | |
9669 | } | |
9670 | ||
85b67bcb AS |
9671 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9672 | struct trace_event_call *call, u64 count, | |
9673 | struct pt_regs *regs, struct hlist_head *head, | |
9674 | struct task_struct *task) | |
9675 | { | |
e87c6bc3 | 9676 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9677 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9678 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9679 | perf_swevent_put_recursion_context(rctx); |
9680 | return; | |
9681 | } | |
9682 | } | |
9683 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9684 | rctx, task); |
85b67bcb AS |
9685 | } |
9686 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9687 | ||
1e1dcd93 | 9688 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9689 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9690 | struct task_struct *task) |
95476b64 FW |
9691 | { |
9692 | struct perf_sample_data data; | |
8fd0fbbe | 9693 | struct perf_event *event; |
1c024eca | 9694 | |
95476b64 | 9695 | struct perf_raw_record raw = { |
7e3f977e DB |
9696 | .frag = { |
9697 | .size = entry_size, | |
9698 | .data = record, | |
9699 | }, | |
95476b64 FW |
9700 | }; |
9701 | ||
1e1dcd93 | 9702 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9703 | data.raw = &raw; |
9704 | ||
1e1dcd93 AS |
9705 | perf_trace_buf_update(record, event_type); |
9706 | ||
8fd0fbbe | 9707 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9708 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9709 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9710 | } |
ecc55f84 | 9711 | |
e6dab5ff AV |
9712 | /* |
9713 | * If we got specified a target task, also iterate its context and | |
9714 | * deliver this event there too. | |
9715 | */ | |
9716 | if (task && task != current) { | |
9717 | struct perf_event_context *ctx; | |
9718 | struct trace_entry *entry = record; | |
9719 | ||
9720 | rcu_read_lock(); | |
9721 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9722 | if (!ctx) | |
9723 | goto unlock; | |
9724 | ||
9725 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9726 | if (event->cpu != smp_processor_id()) |
9727 | continue; | |
e6dab5ff AV |
9728 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9729 | continue; | |
9730 | if (event->attr.config != entry->type) | |
9731 | continue; | |
9732 | if (perf_tp_event_match(event, &data, regs)) | |
9733 | perf_swevent_event(event, count, &data, regs); | |
9734 | } | |
9735 | unlock: | |
9736 | rcu_read_unlock(); | |
9737 | } | |
9738 | ||
ecc55f84 | 9739 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9740 | } |
9741 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9742 | ||
cdd6c482 | 9743 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9744 | { |
1c024eca | 9745 | perf_trace_destroy(event); |
e077df4f PZ |
9746 | } |
9747 | ||
b0a873eb | 9748 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9749 | { |
76e1d904 FW |
9750 | int err; |
9751 | ||
b0a873eb PZ |
9752 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9753 | return -ENOENT; | |
9754 | ||
2481c5fa SE |
9755 | /* |
9756 | * no branch sampling for tracepoint events | |
9757 | */ | |
9758 | if (has_branch_stack(event)) | |
9759 | return -EOPNOTSUPP; | |
9760 | ||
1c024eca PZ |
9761 | err = perf_trace_init(event); |
9762 | if (err) | |
b0a873eb | 9763 | return err; |
e077df4f | 9764 | |
cdd6c482 | 9765 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9766 | |
b0a873eb PZ |
9767 | return 0; |
9768 | } | |
9769 | ||
9770 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9771 | .task_ctx_nr = perf_sw_context, |
9772 | ||
b0a873eb | 9773 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9774 | .add = perf_trace_add, |
9775 | .del = perf_trace_del, | |
9776 | .start = perf_swevent_start, | |
9777 | .stop = perf_swevent_stop, | |
b0a873eb | 9778 | .read = perf_swevent_read, |
b0a873eb PZ |
9779 | }; |
9780 | ||
33ea4b24 | 9781 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9782 | /* |
9783 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9784 | * The flags should match following PMU_FORMAT_ATTR(). | |
9785 | * | |
9786 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9787 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9788 | * |
9789 | * The following values specify a reference counter (or semaphore in the | |
9790 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9791 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9792 | * | |
9793 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9794 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9795 | */ |
9796 | enum perf_probe_config { | |
9797 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9798 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9799 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9800 | }; |
9801 | ||
9802 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9803 | #endif |
e12f03d7 | 9804 | |
a6ca88b2 SL |
9805 | #ifdef CONFIG_KPROBE_EVENTS |
9806 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9807 | &format_attr_retprobe.attr, |
9808 | NULL, | |
9809 | }; | |
9810 | ||
a6ca88b2 | 9811 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9812 | .name = "format", |
a6ca88b2 | 9813 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9814 | }; |
9815 | ||
a6ca88b2 SL |
9816 | static const struct attribute_group *kprobe_attr_groups[] = { |
9817 | &kprobe_format_group, | |
e12f03d7 SL |
9818 | NULL, |
9819 | }; | |
9820 | ||
9821 | static int perf_kprobe_event_init(struct perf_event *event); | |
9822 | static struct pmu perf_kprobe = { | |
9823 | .task_ctx_nr = perf_sw_context, | |
9824 | .event_init = perf_kprobe_event_init, | |
9825 | .add = perf_trace_add, | |
9826 | .del = perf_trace_del, | |
9827 | .start = perf_swevent_start, | |
9828 | .stop = perf_swevent_stop, | |
9829 | .read = perf_swevent_read, | |
a6ca88b2 | 9830 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9831 | }; |
9832 | ||
9833 | static int perf_kprobe_event_init(struct perf_event *event) | |
9834 | { | |
9835 | int err; | |
9836 | bool is_retprobe; | |
9837 | ||
9838 | if (event->attr.type != perf_kprobe.type) | |
9839 | return -ENOENT; | |
32e6e967 | 9840 | |
c9e0924e | 9841 | if (!perfmon_capable()) |
32e6e967 SL |
9842 | return -EACCES; |
9843 | ||
e12f03d7 SL |
9844 | /* |
9845 | * no branch sampling for probe events | |
9846 | */ | |
9847 | if (has_branch_stack(event)) | |
9848 | return -EOPNOTSUPP; | |
9849 | ||
9850 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9851 | err = perf_kprobe_init(event, is_retprobe); | |
9852 | if (err) | |
9853 | return err; | |
9854 | ||
9855 | event->destroy = perf_kprobe_destroy; | |
9856 | ||
9857 | return 0; | |
9858 | } | |
9859 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9860 | ||
33ea4b24 | 9861 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9862 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9863 | ||
9864 | static struct attribute *uprobe_attrs[] = { | |
9865 | &format_attr_retprobe.attr, | |
9866 | &format_attr_ref_ctr_offset.attr, | |
9867 | NULL, | |
9868 | }; | |
9869 | ||
9870 | static struct attribute_group uprobe_format_group = { | |
9871 | .name = "format", | |
9872 | .attrs = uprobe_attrs, | |
9873 | }; | |
9874 | ||
9875 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9876 | &uprobe_format_group, | |
9877 | NULL, | |
9878 | }; | |
9879 | ||
33ea4b24 SL |
9880 | static int perf_uprobe_event_init(struct perf_event *event); |
9881 | static struct pmu perf_uprobe = { | |
9882 | .task_ctx_nr = perf_sw_context, | |
9883 | .event_init = perf_uprobe_event_init, | |
9884 | .add = perf_trace_add, | |
9885 | .del = perf_trace_del, | |
9886 | .start = perf_swevent_start, | |
9887 | .stop = perf_swevent_stop, | |
9888 | .read = perf_swevent_read, | |
a6ca88b2 | 9889 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9890 | }; |
9891 | ||
9892 | static int perf_uprobe_event_init(struct perf_event *event) | |
9893 | { | |
9894 | int err; | |
a6ca88b2 | 9895 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9896 | bool is_retprobe; |
9897 | ||
9898 | if (event->attr.type != perf_uprobe.type) | |
9899 | return -ENOENT; | |
32e6e967 | 9900 | |
c9e0924e | 9901 | if (!perfmon_capable()) |
32e6e967 SL |
9902 | return -EACCES; |
9903 | ||
33ea4b24 SL |
9904 | /* |
9905 | * no branch sampling for probe events | |
9906 | */ | |
9907 | if (has_branch_stack(event)) | |
9908 | return -EOPNOTSUPP; | |
9909 | ||
9910 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9911 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9912 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9913 | if (err) |
9914 | return err; | |
9915 | ||
9916 | event->destroy = perf_uprobe_destroy; | |
9917 | ||
9918 | return 0; | |
9919 | } | |
9920 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9921 | ||
b0a873eb PZ |
9922 | static inline void perf_tp_register(void) |
9923 | { | |
2e80a82a | 9924 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9925 | #ifdef CONFIG_KPROBE_EVENTS |
9926 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9927 | #endif | |
33ea4b24 SL |
9928 | #ifdef CONFIG_UPROBE_EVENTS |
9929 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9930 | #endif | |
e077df4f | 9931 | } |
6fb2915d | 9932 | |
6fb2915d LZ |
9933 | static void perf_event_free_filter(struct perf_event *event) |
9934 | { | |
9935 | ftrace_profile_free_filter(event); | |
9936 | } | |
9937 | ||
aa6a5f3c AS |
9938 | #ifdef CONFIG_BPF_SYSCALL |
9939 | static void bpf_overflow_handler(struct perf_event *event, | |
9940 | struct perf_sample_data *data, | |
9941 | struct pt_regs *regs) | |
9942 | { | |
9943 | struct bpf_perf_event_data_kern ctx = { | |
9944 | .data = data, | |
7d9285e8 | 9945 | .event = event, |
aa6a5f3c | 9946 | }; |
594286b7 | 9947 | struct bpf_prog *prog; |
aa6a5f3c AS |
9948 | int ret = 0; |
9949 | ||
c895f6f7 | 9950 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9951 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9952 | goto out; | |
9953 | rcu_read_lock(); | |
594286b7 YS |
9954 | prog = READ_ONCE(event->prog); |
9955 | if (prog) | |
9956 | ret = bpf_prog_run(prog, &ctx); | |
aa6a5f3c AS |
9957 | rcu_read_unlock(); |
9958 | out: | |
9959 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9960 | if (!ret) |
9961 | return; | |
9962 | ||
9963 | event->orig_overflow_handler(event, data, regs); | |
9964 | } | |
9965 | ||
82e6b1ee AN |
9966 | static int perf_event_set_bpf_handler(struct perf_event *event, |
9967 | struct bpf_prog *prog, | |
9968 | u64 bpf_cookie) | |
aa6a5f3c | 9969 | { |
aa6a5f3c AS |
9970 | if (event->overflow_handler_context) |
9971 | /* hw breakpoint or kernel counter */ | |
9972 | return -EINVAL; | |
9973 | ||
9974 | if (event->prog) | |
9975 | return -EEXIST; | |
9976 | ||
652c1b17 AN |
9977 | if (prog->type != BPF_PROG_TYPE_PERF_EVENT) |
9978 | return -EINVAL; | |
aa6a5f3c | 9979 | |
5d99cb2c SL |
9980 | if (event->attr.precise_ip && |
9981 | prog->call_get_stack && | |
9982 | (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY) || | |
9983 | event->attr.exclude_callchain_kernel || | |
9984 | event->attr.exclude_callchain_user)) { | |
9985 | /* | |
9986 | * On perf_event with precise_ip, calling bpf_get_stack() | |
9987 | * may trigger unwinder warnings and occasional crashes. | |
9988 | * bpf_get_[stack|stackid] works around this issue by using | |
9989 | * callchain attached to perf_sample_data. If the | |
9990 | * perf_event does not full (kernel and user) callchain | |
9991 | * attached to perf_sample_data, do not allow attaching BPF | |
9992 | * program that calls bpf_get_[stack|stackid]. | |
9993 | */ | |
5d99cb2c SL |
9994 | return -EPROTO; |
9995 | } | |
9996 | ||
aa6a5f3c | 9997 | event->prog = prog; |
82e6b1ee | 9998 | event->bpf_cookie = bpf_cookie; |
aa6a5f3c AS |
9999 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); |
10000 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
10001 | return 0; | |
10002 | } | |
10003 | ||
10004 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
10005 | { | |
10006 | struct bpf_prog *prog = event->prog; | |
10007 | ||
10008 | if (!prog) | |
10009 | return; | |
10010 | ||
10011 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
10012 | event->prog = NULL; | |
10013 | bpf_prog_put(prog); | |
10014 | } | |
10015 | #else | |
82e6b1ee AN |
10016 | static int perf_event_set_bpf_handler(struct perf_event *event, |
10017 | struct bpf_prog *prog, | |
10018 | u64 bpf_cookie) | |
aa6a5f3c AS |
10019 | { |
10020 | return -EOPNOTSUPP; | |
10021 | } | |
10022 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
10023 | { | |
10024 | } | |
10025 | #endif | |
10026 | ||
e12f03d7 SL |
10027 | /* |
10028 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
10029 | * with perf_event_open() | |
10030 | */ | |
10031 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
10032 | { | |
10033 | if (event->pmu == &perf_tracepoint) | |
10034 | return true; | |
10035 | #ifdef CONFIG_KPROBE_EVENTS | |
10036 | if (event->pmu == &perf_kprobe) | |
10037 | return true; | |
33ea4b24 SL |
10038 | #endif |
10039 | #ifdef CONFIG_UPROBE_EVENTS | |
10040 | if (event->pmu == &perf_uprobe) | |
10041 | return true; | |
e12f03d7 SL |
10042 | #endif |
10043 | return false; | |
10044 | } | |
10045 | ||
82e6b1ee AN |
10046 | int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, |
10047 | u64 bpf_cookie) | |
2541517c | 10048 | { |
cf5f5cea | 10049 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 10050 | |
e12f03d7 | 10051 | if (!perf_event_is_tracing(event)) |
82e6b1ee | 10052 | return perf_event_set_bpf_handler(event, prog, bpf_cookie); |
2541517c | 10053 | |
98b5c2c6 AS |
10054 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
10055 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
10056 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
10057 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 10058 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
10059 | return -EINVAL; |
10060 | ||
98b5c2c6 | 10061 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea | 10062 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
652c1b17 | 10063 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) |
2541517c | 10064 | return -EINVAL; |
2541517c | 10065 | |
9802d865 JB |
10066 | /* Kprobe override only works for kprobes, not uprobes. */ |
10067 | if (prog->kprobe_override && | |
652c1b17 | 10068 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) |
9802d865 | 10069 | return -EINVAL; |
9802d865 | 10070 | |
cf5f5cea | 10071 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
10072 | int off = trace_event_get_offsets(event->tp_event); |
10073 | ||
652c1b17 | 10074 | if (prog->aux->max_ctx_offset > off) |
32bbe007 | 10075 | return -EACCES; |
32bbe007 | 10076 | } |
2541517c | 10077 | |
82e6b1ee | 10078 | return perf_event_attach_bpf_prog(event, prog, bpf_cookie); |
2541517c AS |
10079 | } |
10080 | ||
b89fbfbb | 10081 | void perf_event_free_bpf_prog(struct perf_event *event) |
2541517c | 10082 | { |
e12f03d7 | 10083 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 10084 | perf_event_free_bpf_handler(event); |
2541517c | 10085 | return; |
2541517c | 10086 | } |
e87c6bc3 | 10087 | perf_event_detach_bpf_prog(event); |
2541517c AS |
10088 | } |
10089 | ||
e077df4f | 10090 | #else |
6fb2915d | 10091 | |
b0a873eb | 10092 | static inline void perf_tp_register(void) |
e077df4f | 10093 | { |
e077df4f | 10094 | } |
6fb2915d | 10095 | |
6fb2915d LZ |
10096 | static void perf_event_free_filter(struct perf_event *event) |
10097 | { | |
10098 | } | |
10099 | ||
82e6b1ee AN |
10100 | int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, |
10101 | u64 bpf_cookie) | |
2541517c AS |
10102 | { |
10103 | return -ENOENT; | |
10104 | } | |
10105 | ||
b89fbfbb | 10106 | void perf_event_free_bpf_prog(struct perf_event *event) |
2541517c AS |
10107 | { |
10108 | } | |
07b139c8 | 10109 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 10110 | |
24f1e32c | 10111 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 10112 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 10113 | { |
f5ffe02e FW |
10114 | struct perf_sample_data sample; |
10115 | struct pt_regs *regs = data; | |
10116 | ||
fd0d000b | 10117 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 10118 | |
a4eaf7f1 | 10119 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 10120 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
10121 | } |
10122 | #endif | |
10123 | ||
375637bc AS |
10124 | /* |
10125 | * Allocate a new address filter | |
10126 | */ | |
10127 | static struct perf_addr_filter * | |
10128 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
10129 | { | |
10130 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
10131 | struct perf_addr_filter *filter; | |
10132 | ||
10133 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
10134 | if (!filter) | |
10135 | return NULL; | |
10136 | ||
10137 | INIT_LIST_HEAD(&filter->entry); | |
10138 | list_add_tail(&filter->entry, filters); | |
10139 | ||
10140 | return filter; | |
10141 | } | |
10142 | ||
10143 | static void free_filters_list(struct list_head *filters) | |
10144 | { | |
10145 | struct perf_addr_filter *filter, *iter; | |
10146 | ||
10147 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 10148 | path_put(&filter->path); |
375637bc AS |
10149 | list_del(&filter->entry); |
10150 | kfree(filter); | |
10151 | } | |
10152 | } | |
10153 | ||
10154 | /* | |
10155 | * Free existing address filters and optionally install new ones | |
10156 | */ | |
10157 | static void perf_addr_filters_splice(struct perf_event *event, | |
10158 | struct list_head *head) | |
10159 | { | |
10160 | unsigned long flags; | |
10161 | LIST_HEAD(list); | |
10162 | ||
10163 | if (!has_addr_filter(event)) | |
10164 | return; | |
10165 | ||
10166 | /* don't bother with children, they don't have their own filters */ | |
10167 | if (event->parent) | |
10168 | return; | |
10169 | ||
10170 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
10171 | ||
10172 | list_splice_init(&event->addr_filters.list, &list); | |
10173 | if (head) | |
10174 | list_splice(head, &event->addr_filters.list); | |
10175 | ||
10176 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
10177 | ||
10178 | free_filters_list(&list); | |
10179 | } | |
10180 | ||
10181 | /* | |
10182 | * Scan through mm's vmas and see if one of them matches the | |
10183 | * @filter; if so, adjust filter's address range. | |
c1e8d7c6 | 10184 | * Called with mm::mmap_lock down for reading. |
375637bc | 10185 | */ |
c60f83b8 AS |
10186 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
10187 | struct mm_struct *mm, | |
10188 | struct perf_addr_filter_range *fr) | |
375637bc AS |
10189 | { |
10190 | struct vm_area_struct *vma; | |
10191 | ||
10192 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 10193 | if (!vma->vm_file) |
375637bc AS |
10194 | continue; |
10195 | ||
c60f83b8 AS |
10196 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
10197 | return; | |
375637bc | 10198 | } |
375637bc AS |
10199 | } |
10200 | ||
10201 | /* | |
10202 | * Update event's address range filters based on the | |
10203 | * task's existing mappings, if any. | |
10204 | */ | |
10205 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
10206 | { | |
10207 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10208 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
10209 | struct perf_addr_filter *filter; | |
10210 | struct mm_struct *mm = NULL; | |
10211 | unsigned int count = 0; | |
10212 | unsigned long flags; | |
10213 | ||
10214 | /* | |
10215 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
10216 | * will stop on the parent's child_mutex that our caller is also holding | |
10217 | */ | |
10218 | if (task == TASK_TOMBSTONE) | |
10219 | return; | |
10220 | ||
52a44f83 | 10221 | if (ifh->nr_file_filters) { |
b89a05b2 | 10222 | mm = get_task_mm(task); |
52a44f83 AS |
10223 | if (!mm) |
10224 | goto restart; | |
375637bc | 10225 | |
d8ed45c5 | 10226 | mmap_read_lock(mm); |
52a44f83 | 10227 | } |
375637bc AS |
10228 | |
10229 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
10230 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
10231 | if (filter->path.dentry) { |
10232 | /* | |
10233 | * Adjust base offset if the filter is associated to a | |
10234 | * binary that needs to be mapped: | |
10235 | */ | |
10236 | event->addr_filter_ranges[count].start = 0; | |
10237 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 10238 | |
c60f83b8 | 10239 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
10240 | } else { |
10241 | event->addr_filter_ranges[count].start = filter->offset; | |
10242 | event->addr_filter_ranges[count].size = filter->size; | |
10243 | } | |
375637bc AS |
10244 | |
10245 | count++; | |
10246 | } | |
10247 | ||
10248 | event->addr_filters_gen++; | |
10249 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
10250 | ||
52a44f83 | 10251 | if (ifh->nr_file_filters) { |
d8ed45c5 | 10252 | mmap_read_unlock(mm); |
375637bc | 10253 | |
52a44f83 AS |
10254 | mmput(mm); |
10255 | } | |
375637bc AS |
10256 | |
10257 | restart: | |
767ae086 | 10258 | perf_event_stop(event, 1); |
375637bc AS |
10259 | } |
10260 | ||
10261 | /* | |
10262 | * Address range filtering: limiting the data to certain | |
10263 | * instruction address ranges. Filters are ioctl()ed to us from | |
10264 | * userspace as ascii strings. | |
10265 | * | |
10266 | * Filter string format: | |
10267 | * | |
10268 | * ACTION RANGE_SPEC | |
10269 | * where ACTION is one of the | |
10270 | * * "filter": limit the trace to this region | |
10271 | * * "start": start tracing from this address | |
10272 | * * "stop": stop tracing at this address/region; | |
10273 | * RANGE_SPEC is | |
10274 | * * for kernel addresses: <start address>[/<size>] | |
10275 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
10276 | * | |
6ed70cf3 AS |
10277 | * if <size> is not specified or is zero, the range is treated as a single |
10278 | * address; not valid for ACTION=="filter". | |
375637bc AS |
10279 | */ |
10280 | enum { | |
e96271f3 | 10281 | IF_ACT_NONE = -1, |
375637bc AS |
10282 | IF_ACT_FILTER, |
10283 | IF_ACT_START, | |
10284 | IF_ACT_STOP, | |
10285 | IF_SRC_FILE, | |
10286 | IF_SRC_KERNEL, | |
10287 | IF_SRC_FILEADDR, | |
10288 | IF_SRC_KERNELADDR, | |
10289 | }; | |
10290 | ||
10291 | enum { | |
10292 | IF_STATE_ACTION = 0, | |
10293 | IF_STATE_SOURCE, | |
10294 | IF_STATE_END, | |
10295 | }; | |
10296 | ||
10297 | static const match_table_t if_tokens = { | |
10298 | { IF_ACT_FILTER, "filter" }, | |
10299 | { IF_ACT_START, "start" }, | |
10300 | { IF_ACT_STOP, "stop" }, | |
10301 | { IF_SRC_FILE, "%u/%u@%s" }, | |
10302 | { IF_SRC_KERNEL, "%u/%u" }, | |
10303 | { IF_SRC_FILEADDR, "%u@%s" }, | |
10304 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 10305 | { IF_ACT_NONE, NULL }, |
375637bc AS |
10306 | }; |
10307 | ||
10308 | /* | |
10309 | * Address filter string parser | |
10310 | */ | |
10311 | static int | |
10312 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
10313 | struct list_head *filters) | |
10314 | { | |
10315 | struct perf_addr_filter *filter = NULL; | |
10316 | char *start, *orig, *filename = NULL; | |
375637bc AS |
10317 | substring_t args[MAX_OPT_ARGS]; |
10318 | int state = IF_STATE_ACTION, token; | |
10319 | unsigned int kernel = 0; | |
10320 | int ret = -EINVAL; | |
10321 | ||
10322 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
10323 | if (!fstr) | |
10324 | return -ENOMEM; | |
10325 | ||
10326 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
10327 | static const enum perf_addr_filter_action_t actions[] = { |
10328 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
10329 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
10330 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
10331 | }; | |
375637bc AS |
10332 | ret = -EINVAL; |
10333 | ||
10334 | if (!*start) | |
10335 | continue; | |
10336 | ||
10337 | /* filter definition begins */ | |
10338 | if (state == IF_STATE_ACTION) { | |
10339 | filter = perf_addr_filter_new(event, filters); | |
10340 | if (!filter) | |
10341 | goto fail; | |
10342 | } | |
10343 | ||
10344 | token = match_token(start, if_tokens, args); | |
10345 | switch (token) { | |
10346 | case IF_ACT_FILTER: | |
10347 | case IF_ACT_START: | |
375637bc AS |
10348 | case IF_ACT_STOP: |
10349 | if (state != IF_STATE_ACTION) | |
10350 | goto fail; | |
10351 | ||
6ed70cf3 | 10352 | filter->action = actions[token]; |
375637bc AS |
10353 | state = IF_STATE_SOURCE; |
10354 | break; | |
10355 | ||
10356 | case IF_SRC_KERNELADDR: | |
10357 | case IF_SRC_KERNEL: | |
10358 | kernel = 1; | |
df561f66 | 10359 | fallthrough; |
375637bc AS |
10360 | |
10361 | case IF_SRC_FILEADDR: | |
10362 | case IF_SRC_FILE: | |
10363 | if (state != IF_STATE_SOURCE) | |
10364 | goto fail; | |
10365 | ||
375637bc AS |
10366 | *args[0].to = 0; |
10367 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
10368 | if (ret) | |
10369 | goto fail; | |
10370 | ||
6ed70cf3 | 10371 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
10372 | *args[1].to = 0; |
10373 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
10374 | if (ret) | |
10375 | goto fail; | |
10376 | } | |
10377 | ||
4059ffd0 | 10378 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 10379 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 | 10380 | |
7bdb157c | 10381 | kfree(filename); |
4059ffd0 | 10382 | filename = match_strdup(&args[fpos]); |
375637bc AS |
10383 | if (!filename) { |
10384 | ret = -ENOMEM; | |
10385 | goto fail; | |
10386 | } | |
10387 | } | |
10388 | ||
10389 | state = IF_STATE_END; | |
10390 | break; | |
10391 | ||
10392 | default: | |
10393 | goto fail; | |
10394 | } | |
10395 | ||
10396 | /* | |
10397 | * Filter definition is fully parsed, validate and install it. | |
10398 | * Make sure that it doesn't contradict itself or the event's | |
10399 | * attribute. | |
10400 | */ | |
10401 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 10402 | ret = -EINVAL; |
375637bc AS |
10403 | if (kernel && event->attr.exclude_kernel) |
10404 | goto fail; | |
10405 | ||
6ed70cf3 AS |
10406 | /* |
10407 | * ACTION "filter" must have a non-zero length region | |
10408 | * specified. | |
10409 | */ | |
10410 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
10411 | !filter->size) | |
10412 | goto fail; | |
10413 | ||
375637bc AS |
10414 | if (!kernel) { |
10415 | if (!filename) | |
10416 | goto fail; | |
10417 | ||
6ce77bfd AS |
10418 | /* |
10419 | * For now, we only support file-based filters | |
10420 | * in per-task events; doing so for CPU-wide | |
10421 | * events requires additional context switching | |
10422 | * trickery, since same object code will be | |
10423 | * mapped at different virtual addresses in | |
10424 | * different processes. | |
10425 | */ | |
10426 | ret = -EOPNOTSUPP; | |
10427 | if (!event->ctx->task) | |
7bdb157c | 10428 | goto fail; |
6ce77bfd | 10429 | |
375637bc | 10430 | /* look up the path and grab its inode */ |
9511bce9 SL |
10431 | ret = kern_path(filename, LOOKUP_FOLLOW, |
10432 | &filter->path); | |
375637bc | 10433 | if (ret) |
7bdb157c | 10434 | goto fail; |
375637bc AS |
10435 | |
10436 | ret = -EINVAL; | |
9511bce9 SL |
10437 | if (!filter->path.dentry || |
10438 | !S_ISREG(d_inode(filter->path.dentry) | |
10439 | ->i_mode)) | |
375637bc | 10440 | goto fail; |
6ce77bfd AS |
10441 | |
10442 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
10443 | } |
10444 | ||
10445 | /* ready to consume more filters */ | |
10446 | state = IF_STATE_ACTION; | |
10447 | filter = NULL; | |
10448 | } | |
10449 | } | |
10450 | ||
10451 | if (state != IF_STATE_ACTION) | |
10452 | goto fail; | |
10453 | ||
7bdb157c | 10454 | kfree(filename); |
375637bc AS |
10455 | kfree(orig); |
10456 | ||
10457 | return 0; | |
10458 | ||
375637bc | 10459 | fail: |
7bdb157c | 10460 | kfree(filename); |
375637bc AS |
10461 | free_filters_list(filters); |
10462 | kfree(orig); | |
10463 | ||
10464 | return ret; | |
10465 | } | |
10466 | ||
10467 | static int | |
10468 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10469 | { | |
10470 | LIST_HEAD(filters); | |
10471 | int ret; | |
10472 | ||
10473 | /* | |
10474 | * Since this is called in perf_ioctl() path, we're already holding | |
10475 | * ctx::mutex. | |
10476 | */ | |
10477 | lockdep_assert_held(&event->ctx->mutex); | |
10478 | ||
10479 | if (WARN_ON_ONCE(event->parent)) | |
10480 | return -EINVAL; | |
10481 | ||
375637bc AS |
10482 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10483 | if (ret) | |
6ce77bfd | 10484 | goto fail_clear_files; |
375637bc AS |
10485 | |
10486 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10487 | if (ret) |
10488 | goto fail_free_filters; | |
375637bc AS |
10489 | |
10490 | /* remove existing filters, if any */ | |
10491 | perf_addr_filters_splice(event, &filters); | |
10492 | ||
10493 | /* install new filters */ | |
10494 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10495 | ||
6ce77bfd AS |
10496 | return ret; |
10497 | ||
10498 | fail_free_filters: | |
10499 | free_filters_list(&filters); | |
10500 | ||
10501 | fail_clear_files: | |
10502 | event->addr_filters.nr_file_filters = 0; | |
10503 | ||
375637bc AS |
10504 | return ret; |
10505 | } | |
10506 | ||
c796bbbe AS |
10507 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10508 | { | |
c796bbbe | 10509 | int ret = -EINVAL; |
e12f03d7 | 10510 | char *filter_str; |
c796bbbe AS |
10511 | |
10512 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10513 | if (IS_ERR(filter_str)) | |
10514 | return PTR_ERR(filter_str); | |
10515 | ||
e12f03d7 SL |
10516 | #ifdef CONFIG_EVENT_TRACING |
10517 | if (perf_event_is_tracing(event)) { | |
10518 | struct perf_event_context *ctx = event->ctx; | |
10519 | ||
10520 | /* | |
10521 | * Beware, here be dragons!! | |
10522 | * | |
10523 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10524 | * the tracepoint stuff does not actually need it. So | |
10525 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10526 | * already have a reference on ctx. | |
10527 | * | |
10528 | * This can result in event getting moved to a different ctx, | |
10529 | * but that does not affect the tracepoint state. | |
10530 | */ | |
10531 | mutex_unlock(&ctx->mutex); | |
10532 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10533 | mutex_lock(&ctx->mutex); | |
10534 | } else | |
10535 | #endif | |
10536 | if (has_addr_filter(event)) | |
375637bc | 10537 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10538 | |
10539 | kfree(filter_str); | |
10540 | return ret; | |
10541 | } | |
10542 | ||
b0a873eb PZ |
10543 | /* |
10544 | * hrtimer based swevent callback | |
10545 | */ | |
f29ac756 | 10546 | |
b0a873eb | 10547 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10548 | { |
b0a873eb PZ |
10549 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10550 | struct perf_sample_data data; | |
10551 | struct pt_regs *regs; | |
10552 | struct perf_event *event; | |
10553 | u64 period; | |
f29ac756 | 10554 | |
b0a873eb | 10555 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10556 | |
10557 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10558 | return HRTIMER_NORESTART; | |
10559 | ||
b0a873eb | 10560 | event->pmu->read(event); |
f344011c | 10561 | |
fd0d000b | 10562 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10563 | regs = get_irq_regs(); |
10564 | ||
10565 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10566 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10567 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10568 | ret = HRTIMER_NORESTART; |
10569 | } | |
24f1e32c | 10570 | |
b0a873eb PZ |
10571 | period = max_t(u64, 10000, event->hw.sample_period); |
10572 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10573 | |
b0a873eb | 10574 | return ret; |
f29ac756 PZ |
10575 | } |
10576 | ||
b0a873eb | 10577 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10578 | { |
b0a873eb | 10579 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10580 | s64 period; |
10581 | ||
10582 | if (!is_sampling_event(event)) | |
10583 | return; | |
f5ffe02e | 10584 | |
5d508e82 FBH |
10585 | period = local64_read(&hwc->period_left); |
10586 | if (period) { | |
10587 | if (period < 0) | |
10588 | period = 10000; | |
fa407f35 | 10589 | |
5d508e82 FBH |
10590 | local64_set(&hwc->period_left, 0); |
10591 | } else { | |
10592 | period = max_t(u64, 10000, hwc->sample_period); | |
10593 | } | |
3497d206 | 10594 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10595 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10596 | } |
b0a873eb PZ |
10597 | |
10598 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10599 | { |
b0a873eb PZ |
10600 | struct hw_perf_event *hwc = &event->hw; |
10601 | ||
6c7e550f | 10602 | if (is_sampling_event(event)) { |
b0a873eb | 10603 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10604 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10605 | |
10606 | hrtimer_cancel(&hwc->hrtimer); | |
10607 | } | |
24f1e32c FW |
10608 | } |
10609 | ||
ba3dd36c PZ |
10610 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10611 | { | |
10612 | struct hw_perf_event *hwc = &event->hw; | |
10613 | ||
10614 | if (!is_sampling_event(event)) | |
10615 | return; | |
10616 | ||
30f9028b | 10617 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10618 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10619 | ||
10620 | /* | |
10621 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10622 | * mapping and avoid the whole period adjust feedback stuff. | |
10623 | */ | |
10624 | if (event->attr.freq) { | |
10625 | long freq = event->attr.sample_freq; | |
10626 | ||
10627 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10628 | hwc->sample_period = event->attr.sample_period; | |
10629 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10630 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10631 | event->attr.freq = 0; |
10632 | } | |
10633 | } | |
10634 | ||
b0a873eb PZ |
10635 | /* |
10636 | * Software event: cpu wall time clock | |
10637 | */ | |
10638 | ||
10639 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10640 | { |
b0a873eb PZ |
10641 | s64 prev; |
10642 | u64 now; | |
10643 | ||
a4eaf7f1 | 10644 | now = local_clock(); |
b0a873eb PZ |
10645 | prev = local64_xchg(&event->hw.prev_count, now); |
10646 | local64_add(now - prev, &event->count); | |
24f1e32c | 10647 | } |
24f1e32c | 10648 | |
a4eaf7f1 | 10649 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10650 | { |
a4eaf7f1 | 10651 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10652 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10653 | } |
10654 | ||
a4eaf7f1 | 10655 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10656 | { |
b0a873eb PZ |
10657 | perf_swevent_cancel_hrtimer(event); |
10658 | cpu_clock_event_update(event); | |
10659 | } | |
f29ac756 | 10660 | |
a4eaf7f1 PZ |
10661 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10662 | { | |
10663 | if (flags & PERF_EF_START) | |
10664 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10665 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10666 | |
10667 | return 0; | |
10668 | } | |
10669 | ||
10670 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10671 | { | |
10672 | cpu_clock_event_stop(event, flags); | |
10673 | } | |
10674 | ||
b0a873eb PZ |
10675 | static void cpu_clock_event_read(struct perf_event *event) |
10676 | { | |
10677 | cpu_clock_event_update(event); | |
10678 | } | |
f344011c | 10679 | |
b0a873eb PZ |
10680 | static int cpu_clock_event_init(struct perf_event *event) |
10681 | { | |
10682 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10683 | return -ENOENT; | |
10684 | ||
10685 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10686 | return -ENOENT; | |
10687 | ||
2481c5fa SE |
10688 | /* |
10689 | * no branch sampling for software events | |
10690 | */ | |
10691 | if (has_branch_stack(event)) | |
10692 | return -EOPNOTSUPP; | |
10693 | ||
ba3dd36c PZ |
10694 | perf_swevent_init_hrtimer(event); |
10695 | ||
b0a873eb | 10696 | return 0; |
f29ac756 PZ |
10697 | } |
10698 | ||
b0a873eb | 10699 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10700 | .task_ctx_nr = perf_sw_context, |
10701 | ||
34f43927 PZ |
10702 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10703 | ||
b0a873eb | 10704 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10705 | .add = cpu_clock_event_add, |
10706 | .del = cpu_clock_event_del, | |
10707 | .start = cpu_clock_event_start, | |
10708 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10709 | .read = cpu_clock_event_read, |
10710 | }; | |
10711 | ||
10712 | /* | |
10713 | * Software event: task time clock | |
10714 | */ | |
10715 | ||
10716 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10717 | { |
b0a873eb PZ |
10718 | u64 prev; |
10719 | s64 delta; | |
5c92d124 | 10720 | |
b0a873eb PZ |
10721 | prev = local64_xchg(&event->hw.prev_count, now); |
10722 | delta = now - prev; | |
10723 | local64_add(delta, &event->count); | |
10724 | } | |
5c92d124 | 10725 | |
a4eaf7f1 | 10726 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10727 | { |
a4eaf7f1 | 10728 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10729 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10730 | } |
10731 | ||
a4eaf7f1 | 10732 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10733 | { |
10734 | perf_swevent_cancel_hrtimer(event); | |
10735 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10736 | } |
10737 | ||
10738 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10739 | { | |
10740 | if (flags & PERF_EF_START) | |
10741 | task_clock_event_start(event, flags); | |
6a694a60 | 10742 | perf_event_update_userpage(event); |
b0a873eb | 10743 | |
a4eaf7f1 PZ |
10744 | return 0; |
10745 | } | |
10746 | ||
10747 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10748 | { | |
10749 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10750 | } |
10751 | ||
10752 | static void task_clock_event_read(struct perf_event *event) | |
10753 | { | |
768a06e2 PZ |
10754 | u64 now = perf_clock(); |
10755 | u64 delta = now - event->ctx->timestamp; | |
10756 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10757 | |
10758 | task_clock_event_update(event, time); | |
10759 | } | |
10760 | ||
10761 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10762 | { |
b0a873eb PZ |
10763 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10764 | return -ENOENT; | |
10765 | ||
10766 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10767 | return -ENOENT; | |
10768 | ||
2481c5fa SE |
10769 | /* |
10770 | * no branch sampling for software events | |
10771 | */ | |
10772 | if (has_branch_stack(event)) | |
10773 | return -EOPNOTSUPP; | |
10774 | ||
ba3dd36c PZ |
10775 | perf_swevent_init_hrtimer(event); |
10776 | ||
b0a873eb | 10777 | return 0; |
6fb2915d LZ |
10778 | } |
10779 | ||
b0a873eb | 10780 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10781 | .task_ctx_nr = perf_sw_context, |
10782 | ||
34f43927 PZ |
10783 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10784 | ||
b0a873eb | 10785 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10786 | .add = task_clock_event_add, |
10787 | .del = task_clock_event_del, | |
10788 | .start = task_clock_event_start, | |
10789 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10790 | .read = task_clock_event_read, |
10791 | }; | |
6fb2915d | 10792 | |
ad5133b7 | 10793 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10794 | { |
e077df4f | 10795 | } |
6fb2915d | 10796 | |
fbbe0701 SB |
10797 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10798 | { | |
10799 | } | |
10800 | ||
ad5133b7 | 10801 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10802 | { |
ad5133b7 | 10803 | return 0; |
6fb2915d LZ |
10804 | } |
10805 | ||
81ec3f3c JO |
10806 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10807 | { | |
10808 | return 0; | |
10809 | } | |
10810 | ||
18ab2cd3 | 10811 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10812 | |
10813 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10814 | { |
fbbe0701 SB |
10815 | __this_cpu_write(nop_txn_flags, flags); |
10816 | ||
10817 | if (flags & ~PERF_PMU_TXN_ADD) | |
10818 | return; | |
10819 | ||
ad5133b7 | 10820 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10821 | } |
10822 | ||
ad5133b7 PZ |
10823 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10824 | { | |
fbbe0701 SB |
10825 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10826 | ||
10827 | __this_cpu_write(nop_txn_flags, 0); | |
10828 | ||
10829 | if (flags & ~PERF_PMU_TXN_ADD) | |
10830 | return 0; | |
10831 | ||
ad5133b7 PZ |
10832 | perf_pmu_enable(pmu); |
10833 | return 0; | |
10834 | } | |
e077df4f | 10835 | |
ad5133b7 | 10836 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10837 | { |
fbbe0701 SB |
10838 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10839 | ||
10840 | __this_cpu_write(nop_txn_flags, 0); | |
10841 | ||
10842 | if (flags & ~PERF_PMU_TXN_ADD) | |
10843 | return; | |
10844 | ||
ad5133b7 | 10845 | perf_pmu_enable(pmu); |
24f1e32c FW |
10846 | } |
10847 | ||
35edc2a5 PZ |
10848 | static int perf_event_idx_default(struct perf_event *event) |
10849 | { | |
c719f560 | 10850 | return 0; |
35edc2a5 PZ |
10851 | } |
10852 | ||
8dc85d54 PZ |
10853 | /* |
10854 | * Ensures all contexts with the same task_ctx_nr have the same | |
10855 | * pmu_cpu_context too. | |
10856 | */ | |
9e317041 | 10857 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10858 | { |
8dc85d54 | 10859 | struct pmu *pmu; |
b326e956 | 10860 | |
8dc85d54 PZ |
10861 | if (ctxn < 0) |
10862 | return NULL; | |
24f1e32c | 10863 | |
8dc85d54 PZ |
10864 | list_for_each_entry(pmu, &pmus, entry) { |
10865 | if (pmu->task_ctx_nr == ctxn) | |
10866 | return pmu->pmu_cpu_context; | |
10867 | } | |
24f1e32c | 10868 | |
8dc85d54 | 10869 | return NULL; |
24f1e32c FW |
10870 | } |
10871 | ||
51676957 PZ |
10872 | static void free_pmu_context(struct pmu *pmu) |
10873 | { | |
df0062b2 WD |
10874 | /* |
10875 | * Static contexts such as perf_sw_context have a global lifetime | |
10876 | * and may be shared between different PMUs. Avoid freeing them | |
10877 | * when a single PMU is going away. | |
10878 | */ | |
10879 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10880 | return; | |
10881 | ||
51676957 | 10882 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10883 | } |
6e855cd4 AS |
10884 | |
10885 | /* | |
10886 | * Let userspace know that this PMU supports address range filtering: | |
10887 | */ | |
10888 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10889 | struct device_attribute *attr, | |
10890 | char *page) | |
10891 | { | |
10892 | struct pmu *pmu = dev_get_drvdata(dev); | |
10893 | ||
10894 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10895 | } | |
10896 | DEVICE_ATTR_RO(nr_addr_filters); | |
10897 | ||
2e80a82a | 10898 | static struct idr pmu_idr; |
d6d020e9 | 10899 | |
abe43400 PZ |
10900 | static ssize_t |
10901 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10902 | { | |
10903 | struct pmu *pmu = dev_get_drvdata(dev); | |
10904 | ||
10905 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10906 | } | |
90826ca7 | 10907 | static DEVICE_ATTR_RO(type); |
abe43400 | 10908 | |
62b85639 SE |
10909 | static ssize_t |
10910 | perf_event_mux_interval_ms_show(struct device *dev, | |
10911 | struct device_attribute *attr, | |
10912 | char *page) | |
10913 | { | |
10914 | struct pmu *pmu = dev_get_drvdata(dev); | |
10915 | ||
10916 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10917 | } | |
10918 | ||
272325c4 PZ |
10919 | static DEFINE_MUTEX(mux_interval_mutex); |
10920 | ||
62b85639 SE |
10921 | static ssize_t |
10922 | perf_event_mux_interval_ms_store(struct device *dev, | |
10923 | struct device_attribute *attr, | |
10924 | const char *buf, size_t count) | |
10925 | { | |
10926 | struct pmu *pmu = dev_get_drvdata(dev); | |
10927 | int timer, cpu, ret; | |
10928 | ||
10929 | ret = kstrtoint(buf, 0, &timer); | |
10930 | if (ret) | |
10931 | return ret; | |
10932 | ||
10933 | if (timer < 1) | |
10934 | return -EINVAL; | |
10935 | ||
10936 | /* same value, noting to do */ | |
10937 | if (timer == pmu->hrtimer_interval_ms) | |
10938 | return count; | |
10939 | ||
272325c4 | 10940 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10941 | pmu->hrtimer_interval_ms = timer; |
10942 | ||
10943 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10944 | cpus_read_lock(); |
272325c4 | 10945 | for_each_online_cpu(cpu) { |
62b85639 SE |
10946 | struct perf_cpu_context *cpuctx; |
10947 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10948 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10949 | ||
272325c4 PZ |
10950 | cpu_function_call(cpu, |
10951 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10952 | } |
a63fbed7 | 10953 | cpus_read_unlock(); |
272325c4 | 10954 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10955 | |
10956 | return count; | |
10957 | } | |
90826ca7 | 10958 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10959 | |
90826ca7 GKH |
10960 | static struct attribute *pmu_dev_attrs[] = { |
10961 | &dev_attr_type.attr, | |
10962 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10963 | NULL, | |
abe43400 | 10964 | }; |
90826ca7 | 10965 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10966 | |
10967 | static int pmu_bus_running; | |
10968 | static struct bus_type pmu_bus = { | |
10969 | .name = "event_source", | |
90826ca7 | 10970 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10971 | }; |
10972 | ||
10973 | static void pmu_dev_release(struct device *dev) | |
10974 | { | |
10975 | kfree(dev); | |
10976 | } | |
10977 | ||
10978 | static int pmu_dev_alloc(struct pmu *pmu) | |
10979 | { | |
10980 | int ret = -ENOMEM; | |
10981 | ||
10982 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10983 | if (!pmu->dev) | |
10984 | goto out; | |
10985 | ||
0c9d42ed | 10986 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10987 | device_initialize(pmu->dev); |
10988 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10989 | if (ret) | |
10990 | goto free_dev; | |
10991 | ||
10992 | dev_set_drvdata(pmu->dev, pmu); | |
10993 | pmu->dev->bus = &pmu_bus; | |
10994 | pmu->dev->release = pmu_dev_release; | |
10995 | ret = device_add(pmu->dev); | |
10996 | if (ret) | |
10997 | goto free_dev; | |
10998 | ||
6e855cd4 AS |
10999 | /* For PMUs with address filters, throw in an extra attribute: */ |
11000 | if (pmu->nr_addr_filters) | |
11001 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
11002 | ||
11003 | if (ret) | |
11004 | goto del_dev; | |
11005 | ||
f3a3a825 JO |
11006 | if (pmu->attr_update) |
11007 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
11008 | ||
11009 | if (ret) | |
11010 | goto del_dev; | |
11011 | ||
abe43400 PZ |
11012 | out: |
11013 | return ret; | |
11014 | ||
6e855cd4 AS |
11015 | del_dev: |
11016 | device_del(pmu->dev); | |
11017 | ||
abe43400 PZ |
11018 | free_dev: |
11019 | put_device(pmu->dev); | |
11020 | goto out; | |
11021 | } | |
11022 | ||
547e9fd7 | 11023 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 11024 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 11025 | |
03d8e80b | 11026 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 11027 | { |
66d258c5 | 11028 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 11029 | |
b0a873eb | 11030 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
11031 | ret = -ENOMEM; |
11032 | pmu->pmu_disable_count = alloc_percpu(int); | |
11033 | if (!pmu->pmu_disable_count) | |
11034 | goto unlock; | |
f29ac756 | 11035 | |
2e80a82a PZ |
11036 | pmu->type = -1; |
11037 | if (!name) | |
11038 | goto skip_type; | |
11039 | pmu->name = name; | |
11040 | ||
66d258c5 PZ |
11041 | if (type != PERF_TYPE_SOFTWARE) { |
11042 | if (type >= 0) | |
11043 | max = type; | |
11044 | ||
11045 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
11046 | if (ret < 0) | |
2e80a82a | 11047 | goto free_pdc; |
66d258c5 PZ |
11048 | |
11049 | WARN_ON(type >= 0 && ret != type); | |
11050 | ||
11051 | type = ret; | |
2e80a82a PZ |
11052 | } |
11053 | pmu->type = type; | |
11054 | ||
abe43400 PZ |
11055 | if (pmu_bus_running) { |
11056 | ret = pmu_dev_alloc(pmu); | |
11057 | if (ret) | |
11058 | goto free_idr; | |
11059 | } | |
11060 | ||
2e80a82a | 11061 | skip_type: |
26657848 PZ |
11062 | if (pmu->task_ctx_nr == perf_hw_context) { |
11063 | static int hw_context_taken = 0; | |
11064 | ||
5101ef20 MR |
11065 | /* |
11066 | * Other than systems with heterogeneous CPUs, it never makes | |
11067 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
11068 | * uncore must use perf_invalid_context. | |
11069 | */ | |
11070 | if (WARN_ON_ONCE(hw_context_taken && | |
11071 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
11072 | pmu->task_ctx_nr = perf_invalid_context; |
11073 | ||
11074 | hw_context_taken = 1; | |
11075 | } | |
11076 | ||
8dc85d54 PZ |
11077 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
11078 | if (pmu->pmu_cpu_context) | |
11079 | goto got_cpu_context; | |
f29ac756 | 11080 | |
c4814202 | 11081 | ret = -ENOMEM; |
108b02cf PZ |
11082 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
11083 | if (!pmu->pmu_cpu_context) | |
abe43400 | 11084 | goto free_dev; |
f344011c | 11085 | |
108b02cf PZ |
11086 | for_each_possible_cpu(cpu) { |
11087 | struct perf_cpu_context *cpuctx; | |
11088 | ||
11089 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 11090 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 11091 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 11092 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 11093 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 11094 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 11095 | |
272325c4 | 11096 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
11097 | |
11098 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
11099 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 11100 | } |
76e1d904 | 11101 | |
8dc85d54 | 11102 | got_cpu_context: |
ad5133b7 PZ |
11103 | if (!pmu->start_txn) { |
11104 | if (pmu->pmu_enable) { | |
11105 | /* | |
11106 | * If we have pmu_enable/pmu_disable calls, install | |
11107 | * transaction stubs that use that to try and batch | |
11108 | * hardware accesses. | |
11109 | */ | |
11110 | pmu->start_txn = perf_pmu_start_txn; | |
11111 | pmu->commit_txn = perf_pmu_commit_txn; | |
11112 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
11113 | } else { | |
fbbe0701 | 11114 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
11115 | pmu->commit_txn = perf_pmu_nop_int; |
11116 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 11117 | } |
5c92d124 | 11118 | } |
15dbf27c | 11119 | |
ad5133b7 PZ |
11120 | if (!pmu->pmu_enable) { |
11121 | pmu->pmu_enable = perf_pmu_nop_void; | |
11122 | pmu->pmu_disable = perf_pmu_nop_void; | |
11123 | } | |
11124 | ||
81ec3f3c JO |
11125 | if (!pmu->check_period) |
11126 | pmu->check_period = perf_event_nop_int; | |
11127 | ||
35edc2a5 PZ |
11128 | if (!pmu->event_idx) |
11129 | pmu->event_idx = perf_event_idx_default; | |
11130 | ||
d44f821b LK |
11131 | /* |
11132 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
11133 | * since these cannot be in the IDR. This way the linear search | |
11134 | * is fast, provided a valid software event is provided. | |
11135 | */ | |
11136 | if (type == PERF_TYPE_SOFTWARE || !name) | |
11137 | list_add_rcu(&pmu->entry, &pmus); | |
11138 | else | |
11139 | list_add_tail_rcu(&pmu->entry, &pmus); | |
11140 | ||
bed5b25a | 11141 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
11142 | ret = 0; |
11143 | unlock: | |
b0a873eb PZ |
11144 | mutex_unlock(&pmus_lock); |
11145 | ||
33696fc0 | 11146 | return ret; |
108b02cf | 11147 | |
abe43400 PZ |
11148 | free_dev: |
11149 | device_del(pmu->dev); | |
11150 | put_device(pmu->dev); | |
11151 | ||
2e80a82a | 11152 | free_idr: |
66d258c5 | 11153 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
11154 | idr_remove(&pmu_idr, pmu->type); |
11155 | ||
108b02cf PZ |
11156 | free_pdc: |
11157 | free_percpu(pmu->pmu_disable_count); | |
11158 | goto unlock; | |
f29ac756 | 11159 | } |
c464c76e | 11160 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 11161 | |
b0a873eb | 11162 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 11163 | { |
b0a873eb PZ |
11164 | mutex_lock(&pmus_lock); |
11165 | list_del_rcu(&pmu->entry); | |
5c92d124 | 11166 | |
0475f9ea | 11167 | /* |
cde8e884 PZ |
11168 | * We dereference the pmu list under both SRCU and regular RCU, so |
11169 | * synchronize against both of those. | |
0475f9ea | 11170 | */ |
b0a873eb | 11171 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 11172 | synchronize_rcu(); |
d6d020e9 | 11173 | |
33696fc0 | 11174 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 11175 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 11176 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 11177 | if (pmu_bus_running) { |
0933840a JO |
11178 | if (pmu->nr_addr_filters) |
11179 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
11180 | device_del(pmu->dev); | |
11181 | put_device(pmu->dev); | |
11182 | } | |
51676957 | 11183 | free_pmu_context(pmu); |
a9f97721 | 11184 | mutex_unlock(&pmus_lock); |
b0a873eb | 11185 | } |
c464c76e | 11186 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 11187 | |
e321d02d KL |
11188 | static inline bool has_extended_regs(struct perf_event *event) |
11189 | { | |
11190 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
11191 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
11192 | } | |
11193 | ||
cc34b98b MR |
11194 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
11195 | { | |
ccd41c86 | 11196 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
11197 | int ret; |
11198 | ||
11199 | if (!try_module_get(pmu->module)) | |
11200 | return -ENODEV; | |
ccd41c86 | 11201 | |
0c7296ca PZ |
11202 | /* |
11203 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
11204 | * for example, validate if the group fits on the PMU. Therefore, | |
11205 | * if this is a sibling event, acquire the ctx->mutex to protect | |
11206 | * the sibling_list. | |
11207 | */ | |
11208 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
11209 | /* |
11210 | * This ctx->mutex can nest when we're called through | |
11211 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
11212 | */ | |
11213 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
11214 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
11215 | BUG_ON(!ctx); |
11216 | } | |
11217 | ||
cc34b98b MR |
11218 | event->pmu = pmu; |
11219 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
11220 | |
11221 | if (ctx) | |
11222 | perf_event_ctx_unlock(event->group_leader, ctx); | |
11223 | ||
cc6795ae | 11224 | if (!ret) { |
e321d02d KL |
11225 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
11226 | has_extended_regs(event)) | |
11227 | ret = -EOPNOTSUPP; | |
11228 | ||
cc6795ae | 11229 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 11230 | event_has_any_exclude_flag(event)) |
cc6795ae | 11231 | ret = -EINVAL; |
e321d02d KL |
11232 | |
11233 | if (ret && event->destroy) | |
11234 | event->destroy(event); | |
cc6795ae AM |
11235 | } |
11236 | ||
cc34b98b MR |
11237 | if (ret) |
11238 | module_put(pmu->module); | |
11239 | ||
11240 | return ret; | |
11241 | } | |
11242 | ||
18ab2cd3 | 11243 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 11244 | { |
55bcf6ef | 11245 | bool extended_type = false; |
66d258c5 | 11246 | int idx, type, ret; |
85c617ab | 11247 | struct pmu *pmu; |
b0a873eb PZ |
11248 | |
11249 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 11250 | |
40999312 KL |
11251 | /* Try parent's PMU first: */ |
11252 | if (event->parent && event->parent->pmu) { | |
11253 | pmu = event->parent->pmu; | |
11254 | ret = perf_try_init_event(pmu, event); | |
11255 | if (!ret) | |
11256 | goto unlock; | |
11257 | } | |
11258 | ||
66d258c5 PZ |
11259 | /* |
11260 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
11261 | * are often aliases for PERF_TYPE_RAW. | |
11262 | */ | |
11263 | type = event->attr.type; | |
55bcf6ef KL |
11264 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) { |
11265 | type = event->attr.config >> PERF_PMU_TYPE_SHIFT; | |
11266 | if (!type) { | |
11267 | type = PERF_TYPE_RAW; | |
11268 | } else { | |
11269 | extended_type = true; | |
11270 | event->attr.config &= PERF_HW_EVENT_MASK; | |
11271 | } | |
11272 | } | |
66d258c5 PZ |
11273 | |
11274 | again: | |
2e80a82a | 11275 | rcu_read_lock(); |
66d258c5 | 11276 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 11277 | rcu_read_unlock(); |
940c5b29 | 11278 | if (pmu) { |
55bcf6ef KL |
11279 | if (event->attr.type != type && type != PERF_TYPE_RAW && |
11280 | !(pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE)) | |
11281 | goto fail; | |
11282 | ||
cc34b98b | 11283 | ret = perf_try_init_event(pmu, event); |
55bcf6ef | 11284 | if (ret == -ENOENT && event->attr.type != type && !extended_type) { |
66d258c5 PZ |
11285 | type = event->attr.type; |
11286 | goto again; | |
11287 | } | |
11288 | ||
940c5b29 LM |
11289 | if (ret) |
11290 | pmu = ERR_PTR(ret); | |
66d258c5 | 11291 | |
2e80a82a | 11292 | goto unlock; |
940c5b29 | 11293 | } |
2e80a82a | 11294 | |
9f0bff11 | 11295 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 11296 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 11297 | if (!ret) |
e5f4d339 | 11298 | goto unlock; |
76e1d904 | 11299 | |
b0a873eb PZ |
11300 | if (ret != -ENOENT) { |
11301 | pmu = ERR_PTR(ret); | |
e5f4d339 | 11302 | goto unlock; |
f344011c | 11303 | } |
5c92d124 | 11304 | } |
55bcf6ef | 11305 | fail: |
e5f4d339 PZ |
11306 | pmu = ERR_PTR(-ENOENT); |
11307 | unlock: | |
b0a873eb | 11308 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 11309 | |
4aeb0b42 | 11310 | return pmu; |
5c92d124 IM |
11311 | } |
11312 | ||
f2fb6bef KL |
11313 | static void attach_sb_event(struct perf_event *event) |
11314 | { | |
11315 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
11316 | ||
11317 | raw_spin_lock(&pel->lock); | |
11318 | list_add_rcu(&event->sb_list, &pel->list); | |
11319 | raw_spin_unlock(&pel->lock); | |
11320 | } | |
11321 | ||
aab5b71e PZ |
11322 | /* |
11323 | * We keep a list of all !task (and therefore per-cpu) events | |
11324 | * that need to receive side-band records. | |
11325 | * | |
11326 | * This avoids having to scan all the various PMU per-cpu contexts | |
11327 | * looking for them. | |
11328 | */ | |
f2fb6bef KL |
11329 | static void account_pmu_sb_event(struct perf_event *event) |
11330 | { | |
a4f144eb | 11331 | if (is_sb_event(event)) |
f2fb6bef KL |
11332 | attach_sb_event(event); |
11333 | } | |
11334 | ||
4beb31f3 FW |
11335 | static void account_event_cpu(struct perf_event *event, int cpu) |
11336 | { | |
11337 | if (event->parent) | |
11338 | return; | |
11339 | ||
4beb31f3 FW |
11340 | if (is_cgroup_event(event)) |
11341 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
11342 | } | |
11343 | ||
555e0c1e FW |
11344 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
11345 | static void account_freq_event_nohz(void) | |
11346 | { | |
11347 | #ifdef CONFIG_NO_HZ_FULL | |
11348 | /* Lock so we don't race with concurrent unaccount */ | |
11349 | spin_lock(&nr_freq_lock); | |
11350 | if (atomic_inc_return(&nr_freq_events) == 1) | |
11351 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
11352 | spin_unlock(&nr_freq_lock); | |
11353 | #endif | |
11354 | } | |
11355 | ||
11356 | static void account_freq_event(void) | |
11357 | { | |
11358 | if (tick_nohz_full_enabled()) | |
11359 | account_freq_event_nohz(); | |
11360 | else | |
11361 | atomic_inc(&nr_freq_events); | |
11362 | } | |
11363 | ||
11364 | ||
766d6c07 FW |
11365 | static void account_event(struct perf_event *event) |
11366 | { | |
25432ae9 PZ |
11367 | bool inc = false; |
11368 | ||
4beb31f3 FW |
11369 | if (event->parent) |
11370 | return; | |
11371 | ||
a5398bff | 11372 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 11373 | inc = true; |
766d6c07 FW |
11374 | if (event->attr.mmap || event->attr.mmap_data) |
11375 | atomic_inc(&nr_mmap_events); | |
88a16a13 JO |
11376 | if (event->attr.build_id) |
11377 | atomic_inc(&nr_build_id_events); | |
766d6c07 FW |
11378 | if (event->attr.comm) |
11379 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
11380 | if (event->attr.namespaces) |
11381 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
11382 | if (event->attr.cgroup) |
11383 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
11384 | if (event->attr.task) |
11385 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
11386 | if (event->attr.freq) |
11387 | account_freq_event(); | |
45ac1403 AH |
11388 | if (event->attr.context_switch) { |
11389 | atomic_inc(&nr_switch_events); | |
25432ae9 | 11390 | inc = true; |
45ac1403 | 11391 | } |
4beb31f3 | 11392 | if (has_branch_stack(event)) |
25432ae9 | 11393 | inc = true; |
4beb31f3 | 11394 | if (is_cgroup_event(event)) |
25432ae9 | 11395 | inc = true; |
76193a94 SL |
11396 | if (event->attr.ksymbol) |
11397 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
11398 | if (event->attr.bpf_event) |
11399 | atomic_inc(&nr_bpf_events); | |
e17d43b9 AH |
11400 | if (event->attr.text_poke) |
11401 | atomic_inc(&nr_text_poke_events); | |
25432ae9 | 11402 | |
9107c89e | 11403 | if (inc) { |
5bce9db1 AS |
11404 | /* |
11405 | * We need the mutex here because static_branch_enable() | |
11406 | * must complete *before* the perf_sched_count increment | |
11407 | * becomes visible. | |
11408 | */ | |
9107c89e PZ |
11409 | if (atomic_inc_not_zero(&perf_sched_count)) |
11410 | goto enabled; | |
11411 | ||
11412 | mutex_lock(&perf_sched_mutex); | |
11413 | if (!atomic_read(&perf_sched_count)) { | |
11414 | static_branch_enable(&perf_sched_events); | |
11415 | /* | |
11416 | * Guarantee that all CPUs observe they key change and | |
11417 | * call the perf scheduling hooks before proceeding to | |
11418 | * install events that need them. | |
11419 | */ | |
0809d954 | 11420 | synchronize_rcu(); |
9107c89e PZ |
11421 | } |
11422 | /* | |
11423 | * Now that we have waited for the sync_sched(), allow further | |
11424 | * increments to by-pass the mutex. | |
11425 | */ | |
11426 | atomic_inc(&perf_sched_count); | |
11427 | mutex_unlock(&perf_sched_mutex); | |
11428 | } | |
11429 | enabled: | |
4beb31f3 FW |
11430 | |
11431 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
11432 | |
11433 | account_pmu_sb_event(event); | |
766d6c07 FW |
11434 | } |
11435 | ||
0793a61d | 11436 | /* |
788faab7 | 11437 | * Allocate and initialize an event structure |
0793a61d | 11438 | */ |
cdd6c482 | 11439 | static struct perf_event * |
c3f00c70 | 11440 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
11441 | struct task_struct *task, |
11442 | struct perf_event *group_leader, | |
11443 | struct perf_event *parent_event, | |
4dc0da86 | 11444 | perf_overflow_handler_t overflow_handler, |
79dff51e | 11445 | void *context, int cgroup_fd) |
0793a61d | 11446 | { |
51b0fe39 | 11447 | struct pmu *pmu; |
cdd6c482 IM |
11448 | struct perf_event *event; |
11449 | struct hw_perf_event *hwc; | |
90983b16 | 11450 | long err = -EINVAL; |
ff65338e | 11451 | int node; |
0793a61d | 11452 | |
66832eb4 ON |
11453 | if ((unsigned)cpu >= nr_cpu_ids) { |
11454 | if (!task || cpu != -1) | |
11455 | return ERR_PTR(-EINVAL); | |
11456 | } | |
97ba62b2 ME |
11457 | if (attr->sigtrap && !task) { |
11458 | /* Requires a task: avoid signalling random tasks. */ | |
11459 | return ERR_PTR(-EINVAL); | |
11460 | } | |
66832eb4 | 11461 | |
ff65338e NK |
11462 | node = (cpu >= 0) ? cpu_to_node(cpu) : -1; |
11463 | event = kmem_cache_alloc_node(perf_event_cache, GFP_KERNEL | __GFP_ZERO, | |
11464 | node); | |
cdd6c482 | 11465 | if (!event) |
d5d2bc0d | 11466 | return ERR_PTR(-ENOMEM); |
0793a61d | 11467 | |
04289bb9 | 11468 | /* |
cdd6c482 | 11469 | * Single events are their own group leaders, with an |
04289bb9 IM |
11470 | * empty sibling list: |
11471 | */ | |
11472 | if (!group_leader) | |
cdd6c482 | 11473 | group_leader = event; |
04289bb9 | 11474 | |
cdd6c482 IM |
11475 | mutex_init(&event->child_mutex); |
11476 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 11477 | |
cdd6c482 IM |
11478 | INIT_LIST_HEAD(&event->event_entry); |
11479 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 11480 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 11481 | init_event_group(event); |
10c6db11 | 11482 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 11483 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 11484 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
11485 | INIT_HLIST_NODE(&event->hlist_entry); |
11486 | ||
10c6db11 | 11487 | |
cdd6c482 | 11488 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 11489 | event->pending_disable = -1; |
e360adbe | 11490 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 11491 | |
cdd6c482 | 11492 | mutex_init(&event->mmap_mutex); |
375637bc | 11493 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11494 | |
a6fa941d | 11495 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11496 | event->cpu = cpu; |
11497 | event->attr = *attr; | |
11498 | event->group_leader = group_leader; | |
11499 | event->pmu = NULL; | |
cdd6c482 | 11500 | event->oncpu = -1; |
a96bbc16 | 11501 | |
cdd6c482 | 11502 | event->parent = parent_event; |
b84fbc9f | 11503 | |
17cf22c3 | 11504 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11505 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11506 | |
cdd6c482 | 11507 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11508 | |
97ba62b2 ME |
11509 | if (event->attr.sigtrap) |
11510 | atomic_set(&event->event_limit, 1); | |
11511 | ||
d580ff86 PZ |
11512 | if (task) { |
11513 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11514 | /* |
50f16a8b PZ |
11515 | * XXX pmu::event_init needs to know what task to account to |
11516 | * and we cannot use the ctx information because we need the | |
11517 | * pmu before we get a ctx. | |
d580ff86 | 11518 | */ |
7b3c92b8 | 11519 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11520 | } |
11521 | ||
34f43927 PZ |
11522 | event->clock = &local_clock; |
11523 | if (parent_event) | |
11524 | event->clock = parent_event->clock; | |
11525 | ||
4dc0da86 | 11526 | if (!overflow_handler && parent_event) { |
b326e956 | 11527 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11528 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11529 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11530 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11531 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11532 | |
85192dbf | 11533 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11534 | event->prog = prog; |
11535 | event->orig_overflow_handler = | |
11536 | parent_event->orig_overflow_handler; | |
11537 | } | |
11538 | #endif | |
4dc0da86 | 11539 | } |
66832eb4 | 11540 | |
1879445d WN |
11541 | if (overflow_handler) { |
11542 | event->overflow_handler = overflow_handler; | |
11543 | event->overflow_handler_context = context; | |
9ecda41a WN |
11544 | } else if (is_write_backward(event)){ |
11545 | event->overflow_handler = perf_event_output_backward; | |
11546 | event->overflow_handler_context = NULL; | |
1879445d | 11547 | } else { |
9ecda41a | 11548 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11549 | event->overflow_handler_context = NULL; |
11550 | } | |
97eaf530 | 11551 | |
0231bb53 | 11552 | perf_event__state_init(event); |
a86ed508 | 11553 | |
4aeb0b42 | 11554 | pmu = NULL; |
b8e83514 | 11555 | |
cdd6c482 | 11556 | hwc = &event->hw; |
bd2b5b12 | 11557 | hwc->sample_period = attr->sample_period; |
0d48696f | 11558 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11559 | hwc->sample_period = 1; |
eced1dfc | 11560 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11561 | |
e7850595 | 11562 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11563 | |
2023b359 | 11564 | /* |
ba5213ae PZ |
11565 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11566 | * See perf_output_read(). | |
2023b359 | 11567 | */ |
ba5213ae | 11568 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11569 | goto err_ns; |
a46a2300 YZ |
11570 | |
11571 | if (!has_branch_stack(event)) | |
11572 | event->attr.branch_sample_type = 0; | |
2023b359 | 11573 | |
b0a873eb | 11574 | pmu = perf_init_event(event); |
85c617ab | 11575 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11576 | err = PTR_ERR(pmu); |
90983b16 | 11577 | goto err_ns; |
621a01ea | 11578 | } |
d5d2bc0d | 11579 | |
09f4e8f0 PZ |
11580 | /* |
11581 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11582 | * be different on other CPUs in the uncore mask. | |
11583 | */ | |
11584 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11585 | err = -EINVAL; | |
11586 | goto err_pmu; | |
11587 | } | |
11588 | ||
ab43762e AS |
11589 | if (event->attr.aux_output && |
11590 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11591 | err = -EOPNOTSUPP; | |
11592 | goto err_pmu; | |
11593 | } | |
11594 | ||
98add2af PZ |
11595 | if (cgroup_fd != -1) { |
11596 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11597 | if (err) | |
11598 | goto err_pmu; | |
11599 | } | |
11600 | ||
bed5b25a AS |
11601 | err = exclusive_event_init(event); |
11602 | if (err) | |
11603 | goto err_pmu; | |
11604 | ||
375637bc | 11605 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11606 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11607 | sizeof(struct perf_addr_filter_range), | |
11608 | GFP_KERNEL); | |
11609 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11610 | err = -ENOMEM; |
375637bc | 11611 | goto err_per_task; |
36cc2b92 | 11612 | } |
375637bc | 11613 | |
18736eef AS |
11614 | /* |
11615 | * Clone the parent's vma offsets: they are valid until exec() | |
11616 | * even if the mm is not shared with the parent. | |
11617 | */ | |
11618 | if (event->parent) { | |
11619 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11620 | ||
11621 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11622 | memcpy(event->addr_filter_ranges, |
11623 | event->parent->addr_filter_ranges, | |
11624 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11625 | raw_spin_unlock_irq(&ifh->lock); |
11626 | } | |
11627 | ||
375637bc AS |
11628 | /* force hw sync on the address filters */ |
11629 | event->addr_filters_gen = 1; | |
11630 | } | |
11631 | ||
cdd6c482 | 11632 | if (!event->parent) { |
927c7a9e | 11633 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11634 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11635 | if (err) |
375637bc | 11636 | goto err_addr_filters; |
d010b332 | 11637 | } |
f344011c | 11638 | } |
9ee318a7 | 11639 | |
da97e184 JFG |
11640 | err = security_perf_event_alloc(event); |
11641 | if (err) | |
11642 | goto err_callchain_buffer; | |
11643 | ||
927a5570 AS |
11644 | /* symmetric to unaccount_event() in _free_event() */ |
11645 | account_event(event); | |
11646 | ||
cdd6c482 | 11647 | return event; |
90983b16 | 11648 | |
da97e184 JFG |
11649 | err_callchain_buffer: |
11650 | if (!event->parent) { | |
11651 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11652 | put_callchain_buffers(); | |
11653 | } | |
375637bc | 11654 | err_addr_filters: |
c60f83b8 | 11655 | kfree(event->addr_filter_ranges); |
375637bc | 11656 | |
bed5b25a AS |
11657 | err_per_task: |
11658 | exclusive_event_destroy(event); | |
11659 | ||
90983b16 | 11660 | err_pmu: |
98add2af PZ |
11661 | if (is_cgroup_event(event)) |
11662 | perf_detach_cgroup(event); | |
90983b16 FW |
11663 | if (event->destroy) |
11664 | event->destroy(event); | |
c464c76e | 11665 | module_put(pmu->module); |
90983b16 FW |
11666 | err_ns: |
11667 | if (event->ns) | |
11668 | put_pid_ns(event->ns); | |
621b6d2e PB |
11669 | if (event->hw.target) |
11670 | put_task_struct(event->hw.target); | |
bdacfaf2 | 11671 | kmem_cache_free(perf_event_cache, event); |
90983b16 FW |
11672 | |
11673 | return ERR_PTR(err); | |
0793a61d TG |
11674 | } |
11675 | ||
cdd6c482 IM |
11676 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11677 | struct perf_event_attr *attr) | |
974802ea | 11678 | { |
974802ea | 11679 | u32 size; |
cdf8073d | 11680 | int ret; |
974802ea | 11681 | |
c2ba8f41 | 11682 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11683 | memset(attr, 0, sizeof(*attr)); |
11684 | ||
11685 | ret = get_user(size, &uattr->size); | |
11686 | if (ret) | |
11687 | return ret; | |
11688 | ||
c2ba8f41 AS |
11689 | /* ABI compatibility quirk: */ |
11690 | if (!size) | |
974802ea | 11691 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11692 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11693 | goto err_size; |
11694 | ||
c2ba8f41 AS |
11695 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11696 | if (ret) { | |
11697 | if (ret == -E2BIG) | |
11698 | goto err_size; | |
11699 | return ret; | |
974802ea PZ |
11700 | } |
11701 | ||
f12f42ac MX |
11702 | attr->size = size; |
11703 | ||
a4faf00d | 11704 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11705 | return -EINVAL; |
11706 | ||
11707 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11708 | return -EINVAL; | |
11709 | ||
11710 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11711 | return -EINVAL; | |
11712 | ||
bce38cd5 SE |
11713 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11714 | u64 mask = attr->branch_sample_type; | |
11715 | ||
11716 | /* only using defined bits */ | |
11717 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11718 | return -EINVAL; | |
11719 | ||
11720 | /* at least one branch bit must be set */ | |
11721 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11722 | return -EINVAL; | |
11723 | ||
bce38cd5 SE |
11724 | /* propagate priv level, when not set for branch */ |
11725 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11726 | ||
11727 | /* exclude_kernel checked on syscall entry */ | |
11728 | if (!attr->exclude_kernel) | |
11729 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11730 | ||
11731 | if (!attr->exclude_user) | |
11732 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11733 | ||
11734 | if (!attr->exclude_hv) | |
11735 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11736 | /* | |
11737 | * adjust user setting (for HW filter setup) | |
11738 | */ | |
11739 | attr->branch_sample_type = mask; | |
11740 | } | |
e712209a | 11741 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11742 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11743 | ret = perf_allow_kernel(attr); | |
11744 | if (ret) | |
11745 | return ret; | |
11746 | } | |
bce38cd5 | 11747 | } |
4018994f | 11748 | |
c5ebcedb | 11749 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11750 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11751 | if (ret) |
11752 | return ret; | |
11753 | } | |
11754 | ||
11755 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11756 | if (!arch_perf_have_user_stack_dump()) | |
11757 | return -ENOSYS; | |
11758 | ||
11759 | /* | |
11760 | * We have __u32 type for the size, but so far | |
11761 | * we can only use __u16 as maximum due to the | |
11762 | * __u16 sample size limit. | |
11763 | */ | |
11764 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11765 | return -EINVAL; |
c5ebcedb | 11766 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11767 | return -EINVAL; |
c5ebcedb | 11768 | } |
4018994f | 11769 | |
5f970521 JO |
11770 | if (!attr->sample_max_stack) |
11771 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11772 | ||
60e2364e SE |
11773 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11774 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11775 | |
11776 | #ifndef CONFIG_CGROUP_PERF | |
11777 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11778 | return -EINVAL; | |
11779 | #endif | |
2a6c6b7d KL |
11780 | if ((attr->sample_type & PERF_SAMPLE_WEIGHT) && |
11781 | (attr->sample_type & PERF_SAMPLE_WEIGHT_STRUCT)) | |
11782 | return -EINVAL; | |
6546b19f | 11783 | |
2b26f0aa ME |
11784 | if (!attr->inherit && attr->inherit_thread) |
11785 | return -EINVAL; | |
11786 | ||
2e498d0a ME |
11787 | if (attr->remove_on_exec && attr->enable_on_exec) |
11788 | return -EINVAL; | |
11789 | ||
97ba62b2 ME |
11790 | if (attr->sigtrap && !attr->remove_on_exec) |
11791 | return -EINVAL; | |
11792 | ||
974802ea PZ |
11793 | out: |
11794 | return ret; | |
11795 | ||
11796 | err_size: | |
11797 | put_user(sizeof(*attr), &uattr->size); | |
11798 | ret = -E2BIG; | |
11799 | goto out; | |
11800 | } | |
11801 | ||
ac9721f3 PZ |
11802 | static int |
11803 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11804 | { |
56de4e8f | 11805 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11806 | int ret = -EINVAL; |
11807 | ||
ac9721f3 | 11808 | if (!output_event) |
a4be7c27 PZ |
11809 | goto set; |
11810 | ||
ac9721f3 PZ |
11811 | /* don't allow circular references */ |
11812 | if (event == output_event) | |
a4be7c27 PZ |
11813 | goto out; |
11814 | ||
0f139300 PZ |
11815 | /* |
11816 | * Don't allow cross-cpu buffers | |
11817 | */ | |
11818 | if (output_event->cpu != event->cpu) | |
11819 | goto out; | |
11820 | ||
11821 | /* | |
76369139 | 11822 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11823 | */ |
11824 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11825 | goto out; | |
11826 | ||
34f43927 PZ |
11827 | /* |
11828 | * Mixing clocks in the same buffer is trouble you don't need. | |
11829 | */ | |
11830 | if (output_event->clock != event->clock) | |
11831 | goto out; | |
11832 | ||
9ecda41a WN |
11833 | /* |
11834 | * Either writing ring buffer from beginning or from end. | |
11835 | * Mixing is not allowed. | |
11836 | */ | |
11837 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11838 | goto out; | |
11839 | ||
45bfb2e5 PZ |
11840 | /* |
11841 | * If both events generate aux data, they must be on the same PMU | |
11842 | */ | |
11843 | if (has_aux(event) && has_aux(output_event) && | |
11844 | event->pmu != output_event->pmu) | |
11845 | goto out; | |
11846 | ||
a4be7c27 | 11847 | set: |
cdd6c482 | 11848 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11849 | /* Can't redirect output if we've got an active mmap() */ |
11850 | if (atomic_read(&event->mmap_count)) | |
11851 | goto unlock; | |
a4be7c27 | 11852 | |
ac9721f3 | 11853 | if (output_event) { |
76369139 FW |
11854 | /* get the rb we want to redirect to */ |
11855 | rb = ring_buffer_get(output_event); | |
11856 | if (!rb) | |
ac9721f3 | 11857 | goto unlock; |
a4be7c27 PZ |
11858 | } |
11859 | ||
b69cf536 | 11860 | ring_buffer_attach(event, rb); |
9bb5d40c | 11861 | |
a4be7c27 | 11862 | ret = 0; |
ac9721f3 PZ |
11863 | unlock: |
11864 | mutex_unlock(&event->mmap_mutex); | |
11865 | ||
a4be7c27 | 11866 | out: |
a4be7c27 PZ |
11867 | return ret; |
11868 | } | |
11869 | ||
f63a8daa PZ |
11870 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11871 | { | |
11872 | if (b < a) | |
11873 | swap(a, b); | |
11874 | ||
11875 | mutex_lock(a); | |
11876 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11877 | } | |
11878 | ||
34f43927 PZ |
11879 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11880 | { | |
11881 | bool nmi_safe = false; | |
11882 | ||
11883 | switch (clk_id) { | |
11884 | case CLOCK_MONOTONIC: | |
11885 | event->clock = &ktime_get_mono_fast_ns; | |
11886 | nmi_safe = true; | |
11887 | break; | |
11888 | ||
11889 | case CLOCK_MONOTONIC_RAW: | |
11890 | event->clock = &ktime_get_raw_fast_ns; | |
11891 | nmi_safe = true; | |
11892 | break; | |
11893 | ||
11894 | case CLOCK_REALTIME: | |
11895 | event->clock = &ktime_get_real_ns; | |
11896 | break; | |
11897 | ||
11898 | case CLOCK_BOOTTIME: | |
9285ec4c | 11899 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11900 | break; |
11901 | ||
11902 | case CLOCK_TAI: | |
9285ec4c | 11903 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11904 | break; |
11905 | ||
11906 | default: | |
11907 | return -EINVAL; | |
11908 | } | |
11909 | ||
11910 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11911 | return -EINVAL; | |
11912 | ||
11913 | return 0; | |
11914 | } | |
11915 | ||
321027c1 PZ |
11916 | /* |
11917 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11918 | * mutexes. | |
11919 | */ | |
11920 | static struct perf_event_context * | |
11921 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11922 | struct perf_event_context *ctx) | |
11923 | { | |
11924 | struct perf_event_context *gctx; | |
11925 | ||
11926 | again: | |
11927 | rcu_read_lock(); | |
11928 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11929 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11930 | rcu_read_unlock(); |
11931 | goto again; | |
11932 | } | |
11933 | rcu_read_unlock(); | |
11934 | ||
11935 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11936 | ||
11937 | if (group_leader->ctx != gctx) { | |
11938 | mutex_unlock(&ctx->mutex); | |
11939 | mutex_unlock(&gctx->mutex); | |
11940 | put_ctx(gctx); | |
11941 | goto again; | |
11942 | } | |
11943 | ||
11944 | return gctx; | |
11945 | } | |
11946 | ||
b068fc04 ME |
11947 | static bool |
11948 | perf_check_permission(struct perf_event_attr *attr, struct task_struct *task) | |
11949 | { | |
11950 | unsigned int ptrace_mode = PTRACE_MODE_READ_REALCREDS; | |
11951 | bool is_capable = perfmon_capable(); | |
11952 | ||
11953 | if (attr->sigtrap) { | |
11954 | /* | |
11955 | * perf_event_attr::sigtrap sends signals to the other task. | |
11956 | * Require the current task to also have CAP_KILL. | |
11957 | */ | |
11958 | rcu_read_lock(); | |
11959 | is_capable &= ns_capable(__task_cred(task)->user_ns, CAP_KILL); | |
11960 | rcu_read_unlock(); | |
11961 | ||
11962 | /* | |
11963 | * If the required capabilities aren't available, checks for | |
11964 | * ptrace permissions: upgrade to ATTACH, since sending signals | |
11965 | * can effectively change the target task. | |
11966 | */ | |
11967 | ptrace_mode = PTRACE_MODE_ATTACH_REALCREDS; | |
11968 | } | |
11969 | ||
11970 | /* | |
11971 | * Preserve ptrace permission check for backwards compatibility. The | |
11972 | * ptrace check also includes checks that the current task and other | |
11973 | * task have matching uids, and is therefore not done here explicitly. | |
11974 | */ | |
11975 | return is_capable || ptrace_may_access(task, ptrace_mode); | |
11976 | } | |
11977 | ||
0793a61d | 11978 | /** |
cdd6c482 | 11979 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11980 | * |
cdd6c482 | 11981 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11982 | * @pid: target pid |
9f66a381 | 11983 | * @cpu: target cpu |
cdd6c482 | 11984 | * @group_fd: group leader event fd |
a1ddf524 | 11985 | * @flags: perf event open flags |
0793a61d | 11986 | */ |
cdd6c482 IM |
11987 | SYSCALL_DEFINE5(perf_event_open, |
11988 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11989 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11990 | { |
b04243ef PZ |
11991 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11992 | struct perf_event *event, *sibling; | |
cdd6c482 | 11993 | struct perf_event_attr attr; |
3f649ab7 | 11994 | struct perf_event_context *ctx, *gctx; |
cdd6c482 | 11995 | struct file *event_file = NULL; |
2903ff01 | 11996 | struct fd group = {NULL, 0}; |
38a81da2 | 11997 | struct task_struct *task = NULL; |
89a1e187 | 11998 | struct pmu *pmu; |
ea635c64 | 11999 | int event_fd; |
b04243ef | 12000 | int move_group = 0; |
dc86cabe | 12001 | int err; |
a21b0b35 | 12002 | int f_flags = O_RDWR; |
79dff51e | 12003 | int cgroup_fd = -1; |
0793a61d | 12004 | |
2743a5b0 | 12005 | /* for future expandability... */ |
e5d1367f | 12006 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
12007 | return -EINVAL; |
12008 | ||
da97e184 JFG |
12009 | /* Do we allow access to perf_event_open(2) ? */ |
12010 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
12011 | if (err) | |
12012 | return err; | |
12013 | ||
dc86cabe IM |
12014 | err = perf_copy_attr(attr_uptr, &attr); |
12015 | if (err) | |
12016 | return err; | |
eab656ae | 12017 | |
0764771d | 12018 | if (!attr.exclude_kernel) { |
da97e184 JFG |
12019 | err = perf_allow_kernel(&attr); |
12020 | if (err) | |
12021 | return err; | |
0764771d PZ |
12022 | } |
12023 | ||
e4222673 | 12024 | if (attr.namespaces) { |
18aa1856 | 12025 | if (!perfmon_capable()) |
e4222673 HB |
12026 | return -EACCES; |
12027 | } | |
12028 | ||
df58ab24 | 12029 | if (attr.freq) { |
cdd6c482 | 12030 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 12031 | return -EINVAL; |
0819b2e3 PZ |
12032 | } else { |
12033 | if (attr.sample_period & (1ULL << 63)) | |
12034 | return -EINVAL; | |
df58ab24 PZ |
12035 | } |
12036 | ||
fc7ce9c7 | 12037 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
12038 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
12039 | err = perf_allow_kernel(&attr); | |
12040 | if (err) | |
12041 | return err; | |
12042 | } | |
fc7ce9c7 | 12043 | |
08ef1af4 OM |
12044 | /* REGS_INTR can leak data, lockdown must prevent this */ |
12045 | if (attr.sample_type & PERF_SAMPLE_REGS_INTR) { | |
12046 | err = security_locked_down(LOCKDOWN_PERF); | |
12047 | if (err) | |
12048 | return err; | |
12049 | } | |
b0c8fdc7 | 12050 | |
e5d1367f SE |
12051 | /* |
12052 | * In cgroup mode, the pid argument is used to pass the fd | |
12053 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
12054 | * designates the cpu on which to monitor threads from that | |
12055 | * cgroup. | |
12056 | */ | |
12057 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
12058 | return -EINVAL; | |
12059 | ||
a21b0b35 YD |
12060 | if (flags & PERF_FLAG_FD_CLOEXEC) |
12061 | f_flags |= O_CLOEXEC; | |
12062 | ||
12063 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
12064 | if (event_fd < 0) |
12065 | return event_fd; | |
12066 | ||
ac9721f3 | 12067 | if (group_fd != -1) { |
2903ff01 AV |
12068 | err = perf_fget_light(group_fd, &group); |
12069 | if (err) | |
d14b12d7 | 12070 | goto err_fd; |
2903ff01 | 12071 | group_leader = group.file->private_data; |
ac9721f3 PZ |
12072 | if (flags & PERF_FLAG_FD_OUTPUT) |
12073 | output_event = group_leader; | |
12074 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
12075 | group_leader = NULL; | |
12076 | } | |
12077 | ||
e5d1367f | 12078 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
12079 | task = find_lively_task_by_vpid(pid); |
12080 | if (IS_ERR(task)) { | |
12081 | err = PTR_ERR(task); | |
12082 | goto err_group_fd; | |
12083 | } | |
12084 | } | |
12085 | ||
1f4ee503 PZ |
12086 | if (task && group_leader && |
12087 | group_leader->attr.inherit != attr.inherit) { | |
12088 | err = -EINVAL; | |
12089 | goto err_task; | |
12090 | } | |
12091 | ||
79dff51e MF |
12092 | if (flags & PERF_FLAG_PID_CGROUP) |
12093 | cgroup_fd = pid; | |
12094 | ||
4dc0da86 | 12095 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 12096 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
12097 | if (IS_ERR(event)) { |
12098 | err = PTR_ERR(event); | |
78af4dc9 | 12099 | goto err_task; |
d14b12d7 SE |
12100 | } |
12101 | ||
53b25335 VW |
12102 | if (is_sampling_event(event)) { |
12103 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 12104 | err = -EOPNOTSUPP; |
53b25335 VW |
12105 | goto err_alloc; |
12106 | } | |
12107 | } | |
12108 | ||
89a1e187 PZ |
12109 | /* |
12110 | * Special case software events and allow them to be part of | |
12111 | * any hardware group. | |
12112 | */ | |
12113 | pmu = event->pmu; | |
b04243ef | 12114 | |
34f43927 PZ |
12115 | if (attr.use_clockid) { |
12116 | err = perf_event_set_clock(event, attr.clockid); | |
12117 | if (err) | |
12118 | goto err_alloc; | |
12119 | } | |
12120 | ||
4ff6a8de DCC |
12121 | if (pmu->task_ctx_nr == perf_sw_context) |
12122 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
12123 | ||
a1150c20 SL |
12124 | if (group_leader) { |
12125 | if (is_software_event(event) && | |
12126 | !in_software_context(group_leader)) { | |
b04243ef | 12127 | /* |
a1150c20 SL |
12128 | * If the event is a sw event, but the group_leader |
12129 | * is on hw context. | |
b04243ef | 12130 | * |
a1150c20 SL |
12131 | * Allow the addition of software events to hw |
12132 | * groups, this is safe because software events | |
12133 | * never fail to schedule. | |
b04243ef | 12134 | */ |
a1150c20 SL |
12135 | pmu = group_leader->ctx->pmu; |
12136 | } else if (!is_software_event(event) && | |
12137 | is_software_event(group_leader) && | |
4ff6a8de | 12138 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
12139 | /* |
12140 | * In case the group is a pure software group, and we | |
12141 | * try to add a hardware event, move the whole group to | |
12142 | * the hardware context. | |
12143 | */ | |
12144 | move_group = 1; | |
12145 | } | |
12146 | } | |
89a1e187 PZ |
12147 | |
12148 | /* | |
12149 | * Get the target context (task or percpu): | |
12150 | */ | |
4af57ef2 | 12151 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
12152 | if (IS_ERR(ctx)) { |
12153 | err = PTR_ERR(ctx); | |
c6be5a5c | 12154 | goto err_alloc; |
89a1e187 PZ |
12155 | } |
12156 | ||
ccff286d | 12157 | /* |
cdd6c482 | 12158 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 12159 | */ |
ac9721f3 | 12160 | if (group_leader) { |
dc86cabe | 12161 | err = -EINVAL; |
04289bb9 | 12162 | |
04289bb9 | 12163 | /* |
ccff286d IM |
12164 | * Do not allow a recursive hierarchy (this new sibling |
12165 | * becoming part of another group-sibling): | |
12166 | */ | |
12167 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 12168 | goto err_context; |
34f43927 PZ |
12169 | |
12170 | /* All events in a group should have the same clock */ | |
12171 | if (group_leader->clock != event->clock) | |
12172 | goto err_context; | |
12173 | ||
ccff286d | 12174 | /* |
64aee2a9 MR |
12175 | * Make sure we're both events for the same CPU; |
12176 | * grouping events for different CPUs is broken; since | |
12177 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 12178 | */ |
64aee2a9 MR |
12179 | if (group_leader->cpu != event->cpu) |
12180 | goto err_context; | |
c3c87e77 | 12181 | |
64aee2a9 MR |
12182 | /* |
12183 | * Make sure we're both on the same task, or both | |
12184 | * per-CPU events. | |
12185 | */ | |
12186 | if (group_leader->ctx->task != ctx->task) | |
12187 | goto err_context; | |
12188 | ||
12189 | /* | |
12190 | * Do not allow to attach to a group in a different task | |
12191 | * or CPU context. If we're moving SW events, we'll fix | |
12192 | * this up later, so allow that. | |
12193 | */ | |
12194 | if (!move_group && group_leader->ctx != ctx) | |
12195 | goto err_context; | |
b04243ef | 12196 | |
3b6f9e5c PM |
12197 | /* |
12198 | * Only a group leader can be exclusive or pinned | |
12199 | */ | |
0d48696f | 12200 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 12201 | goto err_context; |
ac9721f3 PZ |
12202 | } |
12203 | ||
12204 | if (output_event) { | |
12205 | err = perf_event_set_output(event, output_event); | |
12206 | if (err) | |
c3f00c70 | 12207 | goto err_context; |
ac9721f3 | 12208 | } |
0793a61d | 12209 | |
a21b0b35 YD |
12210 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
12211 | f_flags); | |
ea635c64 AV |
12212 | if (IS_ERR(event_file)) { |
12213 | err = PTR_ERR(event_file); | |
201c2f85 | 12214 | event_file = NULL; |
c3f00c70 | 12215 | goto err_context; |
ea635c64 | 12216 | } |
9b51f66d | 12217 | |
78af4dc9 | 12218 | if (task) { |
d01e7f10 | 12219 | err = down_read_interruptible(&task->signal->exec_update_lock); |
78af4dc9 | 12220 | if (err) |
12221 | goto err_file; | |
12222 | ||
12223 | /* | |
d01e7f10 | 12224 | * We must hold exec_update_lock across this and any potential |
78af4dc9 | 12225 | * perf_install_in_context() call for this new event to |
12226 | * serialize against exec() altering our credentials (and the | |
12227 | * perf_event_exit_task() that could imply). | |
12228 | */ | |
12229 | err = -EACCES; | |
b068fc04 | 12230 | if (!perf_check_permission(&attr, task)) |
78af4dc9 | 12231 | goto err_cred; |
12232 | } | |
12233 | ||
b04243ef | 12234 | if (move_group) { |
321027c1 PZ |
12235 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
12236 | ||
84c4e620 PZ |
12237 | if (gctx->task == TASK_TOMBSTONE) { |
12238 | err = -ESRCH; | |
12239 | goto err_locked; | |
12240 | } | |
321027c1 PZ |
12241 | |
12242 | /* | |
12243 | * Check if we raced against another sys_perf_event_open() call | |
12244 | * moving the software group underneath us. | |
12245 | */ | |
12246 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
12247 | /* | |
12248 | * If someone moved the group out from under us, check | |
12249 | * if this new event wound up on the same ctx, if so | |
12250 | * its the regular !move_group case, otherwise fail. | |
12251 | */ | |
12252 | if (gctx != ctx) { | |
12253 | err = -EINVAL; | |
12254 | goto err_locked; | |
12255 | } else { | |
12256 | perf_event_ctx_unlock(group_leader, gctx); | |
12257 | move_group = 0; | |
12258 | } | |
12259 | } | |
8a58ddae AS |
12260 | |
12261 | /* | |
12262 | * Failure to create exclusive events returns -EBUSY. | |
12263 | */ | |
12264 | err = -EBUSY; | |
12265 | if (!exclusive_event_installable(group_leader, ctx)) | |
12266 | goto err_locked; | |
12267 | ||
12268 | for_each_sibling_event(sibling, group_leader) { | |
12269 | if (!exclusive_event_installable(sibling, ctx)) | |
12270 | goto err_locked; | |
12271 | } | |
f55fc2a5 PZ |
12272 | } else { |
12273 | mutex_lock(&ctx->mutex); | |
12274 | } | |
12275 | ||
84c4e620 PZ |
12276 | if (ctx->task == TASK_TOMBSTONE) { |
12277 | err = -ESRCH; | |
12278 | goto err_locked; | |
12279 | } | |
12280 | ||
a723968c PZ |
12281 | if (!perf_event_validate_size(event)) { |
12282 | err = -E2BIG; | |
12283 | goto err_locked; | |
12284 | } | |
12285 | ||
a63fbed7 TG |
12286 | if (!task) { |
12287 | /* | |
12288 | * Check if the @cpu we're creating an event for is online. | |
12289 | * | |
12290 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12291 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12292 | */ | |
12293 | struct perf_cpu_context *cpuctx = | |
12294 | container_of(ctx, struct perf_cpu_context, ctx); | |
12295 | ||
12296 | if (!cpuctx->online) { | |
12297 | err = -ENODEV; | |
12298 | goto err_locked; | |
12299 | } | |
12300 | } | |
12301 | ||
da9ec3d3 MR |
12302 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
12303 | err = -EINVAL; | |
ab43762e | 12304 | goto err_locked; |
da9ec3d3 | 12305 | } |
a63fbed7 | 12306 | |
f55fc2a5 PZ |
12307 | /* |
12308 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
12309 | * because we need to serialize with concurrent event creation. | |
12310 | */ | |
12311 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
12312 | err = -EBUSY; |
12313 | goto err_locked; | |
12314 | } | |
f63a8daa | 12315 | |
f55fc2a5 PZ |
12316 | WARN_ON_ONCE(ctx->parent_ctx); |
12317 | ||
79c9ce57 PZ |
12318 | /* |
12319 | * This is the point on no return; we cannot fail hereafter. This is | |
12320 | * where we start modifying current state. | |
12321 | */ | |
12322 | ||
f55fc2a5 | 12323 | if (move_group) { |
f63a8daa PZ |
12324 | /* |
12325 | * See perf_event_ctx_lock() for comments on the details | |
12326 | * of swizzling perf_event::ctx. | |
12327 | */ | |
45a0e07a | 12328 | perf_remove_from_context(group_leader, 0); |
279b5165 | 12329 | put_ctx(gctx); |
0231bb53 | 12330 | |
edb39592 | 12331 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 12332 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
12333 | put_ctx(gctx); |
12334 | } | |
b04243ef | 12335 | |
f63a8daa PZ |
12336 | /* |
12337 | * Wait for everybody to stop referencing the events through | |
12338 | * the old lists, before installing it on new lists. | |
12339 | */ | |
0cda4c02 | 12340 | synchronize_rcu(); |
f63a8daa | 12341 | |
8f95b435 PZI |
12342 | /* |
12343 | * Install the group siblings before the group leader. | |
12344 | * | |
12345 | * Because a group leader will try and install the entire group | |
12346 | * (through the sibling list, which is still in-tact), we can | |
12347 | * end up with siblings installed in the wrong context. | |
12348 | * | |
12349 | * By installing siblings first we NO-OP because they're not | |
12350 | * reachable through the group lists. | |
12351 | */ | |
edb39592 | 12352 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 12353 | perf_event__state_init(sibling); |
9fc81d87 | 12354 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
12355 | get_ctx(ctx); |
12356 | } | |
8f95b435 PZI |
12357 | |
12358 | /* | |
12359 | * Removing from the context ends up with disabled | |
12360 | * event. What we want here is event in the initial | |
12361 | * startup state, ready to be add into new context. | |
12362 | */ | |
12363 | perf_event__state_init(group_leader); | |
12364 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
12365 | get_ctx(ctx); | |
bed5b25a AS |
12366 | } |
12367 | ||
f73e22ab PZ |
12368 | /* |
12369 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
12370 | * that we're serialized against further additions and before | |
12371 | * perf_install_in_context() which is the point the event is active and | |
12372 | * can use these values. | |
12373 | */ | |
12374 | perf_event__header_size(event); | |
12375 | perf_event__id_header_size(event); | |
12376 | ||
78cd2c74 PZ |
12377 | event->owner = current; |
12378 | ||
e2d37cd2 | 12379 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12380 | perf_unpin_context(ctx); |
f63a8daa | 12381 | |
f55fc2a5 | 12382 | if (move_group) |
321027c1 | 12383 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 12384 | mutex_unlock(&ctx->mutex); |
9b51f66d | 12385 | |
79c9ce57 | 12386 | if (task) { |
f7cfd871 | 12387 | up_read(&task->signal->exec_update_lock); |
79c9ce57 PZ |
12388 | put_task_struct(task); |
12389 | } | |
12390 | ||
cdd6c482 IM |
12391 | mutex_lock(¤t->perf_event_mutex); |
12392 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
12393 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 12394 | |
8a49542c PZ |
12395 | /* |
12396 | * Drop the reference on the group_event after placing the | |
12397 | * new event on the sibling_list. This ensures destruction | |
12398 | * of the group leader will find the pointer to itself in | |
12399 | * perf_group_detach(). | |
12400 | */ | |
2903ff01 | 12401 | fdput(group); |
ea635c64 AV |
12402 | fd_install(event_fd, event_file); |
12403 | return event_fd; | |
0793a61d | 12404 | |
f55fc2a5 PZ |
12405 | err_locked: |
12406 | if (move_group) | |
321027c1 | 12407 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 | 12408 | mutex_unlock(&ctx->mutex); |
78af4dc9 | 12409 | err_cred: |
12410 | if (task) | |
d01e7f10 | 12411 | up_read(&task->signal->exec_update_lock); |
78af4dc9 | 12412 | err_file: |
f55fc2a5 | 12413 | fput(event_file); |
c3f00c70 | 12414 | err_context: |
fe4b04fa | 12415 | perf_unpin_context(ctx); |
ea635c64 | 12416 | put_ctx(ctx); |
c6be5a5c | 12417 | err_alloc: |
13005627 PZ |
12418 | /* |
12419 | * If event_file is set, the fput() above will have called ->release() | |
12420 | * and that will take care of freeing the event. | |
12421 | */ | |
12422 | if (!event_file) | |
12423 | free_event(event); | |
1f4ee503 | 12424 | err_task: |
e7d0bc04 PZ |
12425 | if (task) |
12426 | put_task_struct(task); | |
89a1e187 | 12427 | err_group_fd: |
2903ff01 | 12428 | fdput(group); |
ea635c64 AV |
12429 | err_fd: |
12430 | put_unused_fd(event_fd); | |
dc86cabe | 12431 | return err; |
0793a61d TG |
12432 | } |
12433 | ||
fb0459d7 AV |
12434 | /** |
12435 | * perf_event_create_kernel_counter | |
12436 | * | |
12437 | * @attr: attributes of the counter to create | |
12438 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 12439 | * @task: task to profile (NULL for percpu) |
a1ddf524 HX |
12440 | * @overflow_handler: callback to trigger when we hit the event |
12441 | * @context: context data could be used in overflow_handler callback | |
fb0459d7 AV |
12442 | */ |
12443 | struct perf_event * | |
12444 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 12445 | struct task_struct *task, |
4dc0da86 AK |
12446 | perf_overflow_handler_t overflow_handler, |
12447 | void *context) | |
fb0459d7 | 12448 | { |
fb0459d7 | 12449 | struct perf_event_context *ctx; |
c3f00c70 | 12450 | struct perf_event *event; |
fb0459d7 | 12451 | int err; |
d859e29f | 12452 | |
dce5affb AS |
12453 | /* |
12454 | * Grouping is not supported for kernel events, neither is 'AUX', | |
12455 | * make sure the caller's intentions are adjusted. | |
12456 | */ | |
12457 | if (attr->aux_output) | |
12458 | return ERR_PTR(-EINVAL); | |
12459 | ||
4dc0da86 | 12460 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 12461 | overflow_handler, context, -1); |
c3f00c70 PZ |
12462 | if (IS_ERR(event)) { |
12463 | err = PTR_ERR(event); | |
12464 | goto err; | |
12465 | } | |
d859e29f | 12466 | |
f8697762 | 12467 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 12468 | event->owner = TASK_TOMBSTONE; |
f8697762 | 12469 | |
f25d8ba9 AS |
12470 | /* |
12471 | * Get the target context (task or percpu): | |
12472 | */ | |
4af57ef2 | 12473 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
12474 | if (IS_ERR(ctx)) { |
12475 | err = PTR_ERR(ctx); | |
c3f00c70 | 12476 | goto err_free; |
d859e29f | 12477 | } |
fb0459d7 | 12478 | |
fb0459d7 AV |
12479 | WARN_ON_ONCE(ctx->parent_ctx); |
12480 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
12481 | if (ctx->task == TASK_TOMBSTONE) { |
12482 | err = -ESRCH; | |
12483 | goto err_unlock; | |
12484 | } | |
12485 | ||
a63fbed7 TG |
12486 | if (!task) { |
12487 | /* | |
12488 | * Check if the @cpu we're creating an event for is online. | |
12489 | * | |
12490 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12491 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12492 | */ | |
12493 | struct perf_cpu_context *cpuctx = | |
12494 | container_of(ctx, struct perf_cpu_context, ctx); | |
12495 | if (!cpuctx->online) { | |
12496 | err = -ENODEV; | |
12497 | goto err_unlock; | |
12498 | } | |
12499 | } | |
12500 | ||
bed5b25a | 12501 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 12502 | err = -EBUSY; |
84c4e620 | 12503 | goto err_unlock; |
bed5b25a AS |
12504 | } |
12505 | ||
4ce54af8 | 12506 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12507 | perf_unpin_context(ctx); |
fb0459d7 AV |
12508 | mutex_unlock(&ctx->mutex); |
12509 | ||
fb0459d7 AV |
12510 | return event; |
12511 | ||
84c4e620 PZ |
12512 | err_unlock: |
12513 | mutex_unlock(&ctx->mutex); | |
12514 | perf_unpin_context(ctx); | |
12515 | put_ctx(ctx); | |
c3f00c70 PZ |
12516 | err_free: |
12517 | free_event(event); | |
12518 | err: | |
c6567f64 | 12519 | return ERR_PTR(err); |
9b51f66d | 12520 | } |
fb0459d7 | 12521 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 12522 | |
0cda4c02 YZ |
12523 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
12524 | { | |
12525 | struct perf_event_context *src_ctx; | |
12526 | struct perf_event_context *dst_ctx; | |
12527 | struct perf_event *event, *tmp; | |
12528 | LIST_HEAD(events); | |
12529 | ||
12530 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
12531 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
12532 | ||
f63a8daa PZ |
12533 | /* |
12534 | * See perf_event_ctx_lock() for comments on the details | |
12535 | * of swizzling perf_event::ctx. | |
12536 | */ | |
12537 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
12538 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12539 | event_entry) { | |
45a0e07a | 12540 | perf_remove_from_context(event, 0); |
9a545de0 | 12541 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12542 | put_ctx(src_ctx); |
9886167d | 12543 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12544 | } |
0cda4c02 | 12545 | |
8f95b435 PZI |
12546 | /* |
12547 | * Wait for the events to quiesce before re-instating them. | |
12548 | */ | |
0cda4c02 YZ |
12549 | synchronize_rcu(); |
12550 | ||
8f95b435 PZI |
12551 | /* |
12552 | * Re-instate events in 2 passes. | |
12553 | * | |
12554 | * Skip over group leaders and only install siblings on this first | |
12555 | * pass, siblings will not get enabled without a leader, however a | |
12556 | * leader will enable its siblings, even if those are still on the old | |
12557 | * context. | |
12558 | */ | |
12559 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12560 | if (event->group_leader == event) | |
12561 | continue; | |
12562 | ||
12563 | list_del(&event->migrate_entry); | |
12564 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12565 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12566 | account_event_cpu(event, dst_cpu); | |
12567 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12568 | get_ctx(dst_ctx); | |
12569 | } | |
12570 | ||
12571 | /* | |
12572 | * Once all the siblings are setup properly, install the group leaders | |
12573 | * to make it go. | |
12574 | */ | |
9886167d PZ |
12575 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12576 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12577 | if (event->state >= PERF_EVENT_STATE_OFF) |
12578 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12579 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12580 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12581 | get_ctx(dst_ctx); | |
12582 | } | |
12583 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12584 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12585 | } |
12586 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12587 | ||
ef54c1a4 | 12588 | static void sync_child_event(struct perf_event *child_event) |
d859e29f | 12589 | { |
cdd6c482 | 12590 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12591 | u64 child_val; |
d859e29f | 12592 | |
ef54c1a4 PZ |
12593 | if (child_event->attr.inherit_stat) { |
12594 | struct task_struct *task = child_event->ctx->task; | |
12595 | ||
12596 | if (task && task != TASK_TOMBSTONE) | |
12597 | perf_event_read_event(child_event, task); | |
12598 | } | |
38b200d6 | 12599 | |
b5e58793 | 12600 | child_val = perf_event_count(child_event); |
d859e29f PM |
12601 | |
12602 | /* | |
12603 | * Add back the child's count to the parent's count: | |
12604 | */ | |
a6e6dea6 | 12605 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12606 | atomic64_add(child_event->total_time_enabled, |
12607 | &parent_event->child_total_time_enabled); | |
12608 | atomic64_add(child_event->total_time_running, | |
12609 | &parent_event->child_total_time_running); | |
d859e29f PM |
12610 | } |
12611 | ||
9b51f66d | 12612 | static void |
ef54c1a4 | 12613 | perf_event_exit_event(struct perf_event *event, struct perf_event_context *ctx) |
9b51f66d | 12614 | { |
ef54c1a4 PZ |
12615 | struct perf_event *parent_event = event->parent; |
12616 | unsigned long detach_flags = 0; | |
8ba289b8 | 12617 | |
ef54c1a4 PZ |
12618 | if (parent_event) { |
12619 | /* | |
12620 | * Do not destroy the 'original' grouping; because of the | |
12621 | * context switch optimization the original events could've | |
12622 | * ended up in a random child task. | |
12623 | * | |
12624 | * If we were to destroy the original group, all group related | |
12625 | * operations would cease to function properly after this | |
12626 | * random child dies. | |
12627 | * | |
12628 | * Do destroy all inherited groups, we don't care about those | |
12629 | * and being thorough is better. | |
12630 | */ | |
12631 | detach_flags = DETACH_GROUP | DETACH_CHILD; | |
12632 | mutex_lock(&parent_event->child_mutex); | |
12633 | } | |
32132a3d | 12634 | |
ef54c1a4 PZ |
12635 | perf_remove_from_context(event, detach_flags); |
12636 | ||
12637 | raw_spin_lock_irq(&ctx->lock); | |
12638 | if (event->state > PERF_EVENT_STATE_EXIT) | |
12639 | perf_event_set_state(event, PERF_EVENT_STATE_EXIT); | |
12640 | raw_spin_unlock_irq(&ctx->lock); | |
0cc0c027 | 12641 | |
9b51f66d | 12642 | /* |
ef54c1a4 | 12643 | * Child events can be freed. |
9b51f66d | 12644 | */ |
ef54c1a4 PZ |
12645 | if (parent_event) { |
12646 | mutex_unlock(&parent_event->child_mutex); | |
12647 | /* | |
12648 | * Kick perf_poll() for is_event_hup(); | |
12649 | */ | |
12650 | perf_event_wakeup(parent_event); | |
12651 | free_event(event); | |
12652 | put_event(parent_event); | |
8ba289b8 | 12653 | return; |
4bcf349a | 12654 | } |
8ba289b8 PZ |
12655 | |
12656 | /* | |
ef54c1a4 | 12657 | * Parent events are governed by their filedesc, retain them. |
8ba289b8 | 12658 | */ |
ef54c1a4 | 12659 | perf_event_wakeup(event); |
9b51f66d IM |
12660 | } |
12661 | ||
8dc85d54 | 12662 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12663 | { |
211de6eb | 12664 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12665 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12666 | |
12667 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12668 | |
6a3351b6 | 12669 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12670 | if (!child_ctx) |
9b51f66d IM |
12671 | return; |
12672 | ||
ad3a37de | 12673 | /* |
6a3351b6 PZ |
12674 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12675 | * ctx::mutex over the entire thing. This serializes against almost | |
12676 | * everything that wants to access the ctx. | |
12677 | * | |
12678 | * The exception is sys_perf_event_open() / | |
12679 | * perf_event_create_kernel_count() which does find_get_context() | |
12680 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12681 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12682 | */ |
6a3351b6 | 12683 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12684 | |
12685 | /* | |
6a3351b6 PZ |
12686 | * In a single ctx::lock section, de-schedule the events and detach the |
12687 | * context from the task such that we cannot ever get it scheduled back | |
12688 | * in. | |
c93f7669 | 12689 | */ |
6a3351b6 | 12690 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12691 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12692 | |
71a851b4 | 12693 | /* |
63b6da39 PZ |
12694 | * Now that the context is inactive, destroy the task <-> ctx relation |
12695 | * and mark the context dead. | |
71a851b4 | 12696 | */ |
63b6da39 PZ |
12697 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12698 | put_ctx(child_ctx); /* cannot be last */ | |
12699 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12700 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12701 | |
211de6eb | 12702 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12703 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12704 | |
211de6eb PZ |
12705 | if (clone_ctx) |
12706 | put_ctx(clone_ctx); | |
4a1c0f26 | 12707 | |
9f498cc5 | 12708 | /* |
cdd6c482 IM |
12709 | * Report the task dead after unscheduling the events so that we |
12710 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12711 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12712 | */ |
cdd6c482 | 12713 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12714 | |
ebf905fc | 12715 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
ef54c1a4 | 12716 | perf_event_exit_event(child_event, child_ctx); |
8bc20959 | 12717 | |
a63eaf34 PM |
12718 | mutex_unlock(&child_ctx->mutex); |
12719 | ||
12720 | put_ctx(child_ctx); | |
9b51f66d IM |
12721 | } |
12722 | ||
8dc85d54 PZ |
12723 | /* |
12724 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12725 | * |
f7cfd871 | 12726 | * Can be called with exec_update_lock held when called from |
96ecee29 | 12727 | * setup_new_exec(). |
8dc85d54 PZ |
12728 | */ |
12729 | void perf_event_exit_task(struct task_struct *child) | |
12730 | { | |
8882135b | 12731 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12732 | int ctxn; |
12733 | ||
8882135b PZ |
12734 | mutex_lock(&child->perf_event_mutex); |
12735 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12736 | owner_entry) { | |
12737 | list_del_init(&event->owner_entry); | |
12738 | ||
12739 | /* | |
12740 | * Ensure the list deletion is visible before we clear | |
12741 | * the owner, closes a race against perf_release() where | |
12742 | * we need to serialize on the owner->perf_event_mutex. | |
12743 | */ | |
f47c02c0 | 12744 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12745 | } |
12746 | mutex_unlock(&child->perf_event_mutex); | |
12747 | ||
8dc85d54 PZ |
12748 | for_each_task_context_nr(ctxn) |
12749 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12750 | |
12751 | /* | |
12752 | * The perf_event_exit_task_context calls perf_event_task | |
12753 | * with child's task_ctx, which generates EXIT events for | |
12754 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12755 | * At this point we need to send EXIT events to cpu contexts. | |
12756 | */ | |
12757 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12758 | } |
12759 | ||
889ff015 FW |
12760 | static void perf_free_event(struct perf_event *event, |
12761 | struct perf_event_context *ctx) | |
12762 | { | |
12763 | struct perf_event *parent = event->parent; | |
12764 | ||
12765 | if (WARN_ON_ONCE(!parent)) | |
12766 | return; | |
12767 | ||
12768 | mutex_lock(&parent->child_mutex); | |
12769 | list_del_init(&event->child_list); | |
12770 | mutex_unlock(&parent->child_mutex); | |
12771 | ||
a6fa941d | 12772 | put_event(parent); |
889ff015 | 12773 | |
652884fe | 12774 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12775 | perf_group_detach(event); |
889ff015 | 12776 | list_del_event(event, ctx); |
652884fe | 12777 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12778 | free_event(event); |
12779 | } | |
12780 | ||
bbbee908 | 12781 | /* |
1cf8dfe8 PZ |
12782 | * Free a context as created by inheritance by perf_event_init_task() below, |
12783 | * used by fork() in case of fail. | |
652884fe | 12784 | * |
1cf8dfe8 PZ |
12785 | * Even though the task has never lived, the context and events have been |
12786 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12787 | */ |
cdd6c482 | 12788 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12789 | { |
8dc85d54 | 12790 | struct perf_event_context *ctx; |
cdd6c482 | 12791 | struct perf_event *event, *tmp; |
8dc85d54 | 12792 | int ctxn; |
bbbee908 | 12793 | |
8dc85d54 PZ |
12794 | for_each_task_context_nr(ctxn) { |
12795 | ctx = task->perf_event_ctxp[ctxn]; | |
12796 | if (!ctx) | |
12797 | continue; | |
bbbee908 | 12798 | |
8dc85d54 | 12799 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12800 | raw_spin_lock_irq(&ctx->lock); |
12801 | /* | |
12802 | * Destroy the task <-> ctx relation and mark the context dead. | |
12803 | * | |
12804 | * This is important because even though the task hasn't been | |
12805 | * exposed yet the context has been (through child_list). | |
12806 | */ | |
12807 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12808 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12809 | put_task_struct(task); /* cannot be last */ | |
12810 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12811 | |
15121c78 | 12812 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12813 | perf_free_event(event, ctx); |
bbbee908 | 12814 | |
8dc85d54 | 12815 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12816 | |
12817 | /* | |
12818 | * perf_event_release_kernel() could've stolen some of our | |
12819 | * child events and still have them on its free_list. In that | |
12820 | * case we must wait for these events to have been freed (in | |
12821 | * particular all their references to this task must've been | |
12822 | * dropped). | |
12823 | * | |
12824 | * Without this copy_process() will unconditionally free this | |
12825 | * task (irrespective of its reference count) and | |
12826 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12827 | * use-after-free. | |
12828 | * | |
12829 | * Wait for all events to drop their context reference. | |
12830 | */ | |
12831 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12832 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12833 | } |
889ff015 FW |
12834 | } |
12835 | ||
4e231c79 PZ |
12836 | void perf_event_delayed_put(struct task_struct *task) |
12837 | { | |
12838 | int ctxn; | |
12839 | ||
12840 | for_each_task_context_nr(ctxn) | |
12841 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12842 | } | |
12843 | ||
e03e7ee3 | 12844 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12845 | { |
02e5ad97 | 12846 | struct file *file = fget(fd); |
e03e7ee3 AS |
12847 | if (!file) |
12848 | return ERR_PTR(-EBADF); | |
ffe8690c | 12849 | |
e03e7ee3 AS |
12850 | if (file->f_op != &perf_fops) { |
12851 | fput(file); | |
12852 | return ERR_PTR(-EBADF); | |
12853 | } | |
ffe8690c | 12854 | |
e03e7ee3 | 12855 | return file; |
ffe8690c KX |
12856 | } |
12857 | ||
f8d959a5 YS |
12858 | const struct perf_event *perf_get_event(struct file *file) |
12859 | { | |
12860 | if (file->f_op != &perf_fops) | |
12861 | return ERR_PTR(-EINVAL); | |
12862 | ||
12863 | return file->private_data; | |
12864 | } | |
12865 | ||
ffe8690c KX |
12866 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12867 | { | |
12868 | if (!event) | |
12869 | return ERR_PTR(-EINVAL); | |
12870 | ||
12871 | return &event->attr; | |
12872 | } | |
12873 | ||
97dee4f3 | 12874 | /* |
788faab7 | 12875 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12876 | * |
12877 | * Returns: | |
12878 | * - valid pointer on success | |
12879 | * - NULL for orphaned events | |
12880 | * - IS_ERR() on error | |
97dee4f3 PZ |
12881 | */ |
12882 | static struct perf_event * | |
12883 | inherit_event(struct perf_event *parent_event, | |
12884 | struct task_struct *parent, | |
12885 | struct perf_event_context *parent_ctx, | |
12886 | struct task_struct *child, | |
12887 | struct perf_event *group_leader, | |
12888 | struct perf_event_context *child_ctx) | |
12889 | { | |
8ca2bd41 | 12890 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12891 | struct perf_event *child_event; |
cee010ec | 12892 | unsigned long flags; |
97dee4f3 PZ |
12893 | |
12894 | /* | |
12895 | * Instead of creating recursive hierarchies of events, | |
12896 | * we link inherited events back to the original parent, | |
12897 | * which has a filp for sure, which we use as the reference | |
12898 | * count: | |
12899 | */ | |
12900 | if (parent_event->parent) | |
12901 | parent_event = parent_event->parent; | |
12902 | ||
12903 | child_event = perf_event_alloc(&parent_event->attr, | |
12904 | parent_event->cpu, | |
d580ff86 | 12905 | child, |
97dee4f3 | 12906 | group_leader, parent_event, |
79dff51e | 12907 | NULL, NULL, -1); |
97dee4f3 PZ |
12908 | if (IS_ERR(child_event)) |
12909 | return child_event; | |
a6fa941d | 12910 | |
313ccb96 JO |
12911 | |
12912 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12913 | !child_ctx->task_ctx_data) { | |
12914 | struct pmu *pmu = child_event->pmu; | |
12915 | ||
ff9ff926 | 12916 | child_ctx->task_ctx_data = alloc_task_ctx_data(pmu); |
313ccb96 JO |
12917 | if (!child_ctx->task_ctx_data) { |
12918 | free_event(child_event); | |
697d8778 | 12919 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12920 | } |
12921 | } | |
12922 | ||
c6e5b732 PZ |
12923 | /* |
12924 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12925 | * must be under the same lock in order to serialize against | |
12926 | * perf_event_release_kernel(), such that either we must observe | |
12927 | * is_orphaned_event() or they will observe us on the child_list. | |
12928 | */ | |
12929 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12930 | if (is_orphaned_event(parent_event) || |
12931 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12932 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12933 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12934 | free_event(child_event); |
12935 | return NULL; | |
12936 | } | |
12937 | ||
97dee4f3 PZ |
12938 | get_ctx(child_ctx); |
12939 | ||
12940 | /* | |
12941 | * Make the child state follow the state of the parent event, | |
12942 | * not its attr.disabled bit. We hold the parent's mutex, | |
12943 | * so we won't race with perf_event_{en, dis}able_family. | |
12944 | */ | |
1929def9 | 12945 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12946 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12947 | else | |
12948 | child_event->state = PERF_EVENT_STATE_OFF; | |
12949 | ||
12950 | if (parent_event->attr.freq) { | |
12951 | u64 sample_period = parent_event->hw.sample_period; | |
12952 | struct hw_perf_event *hwc = &child_event->hw; | |
12953 | ||
12954 | hwc->sample_period = sample_period; | |
12955 | hwc->last_period = sample_period; | |
12956 | ||
12957 | local64_set(&hwc->period_left, sample_period); | |
12958 | } | |
12959 | ||
12960 | child_event->ctx = child_ctx; | |
12961 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12962 | child_event->overflow_handler_context |
12963 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12964 | |
614b6780 TG |
12965 | /* |
12966 | * Precalculate sample_data sizes | |
12967 | */ | |
12968 | perf_event__header_size(child_event); | |
6844c09d | 12969 | perf_event__id_header_size(child_event); |
614b6780 | 12970 | |
97dee4f3 PZ |
12971 | /* |
12972 | * Link it up in the child's context: | |
12973 | */ | |
cee010ec | 12974 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12975 | add_event_to_ctx(child_event, child_ctx); |
ef54c1a4 | 12976 | child_event->attach_state |= PERF_ATTACH_CHILD; |
cee010ec | 12977 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12978 | |
97dee4f3 PZ |
12979 | /* |
12980 | * Link this into the parent event's child list | |
12981 | */ | |
97dee4f3 PZ |
12982 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12983 | mutex_unlock(&parent_event->child_mutex); | |
12984 | ||
12985 | return child_event; | |
12986 | } | |
12987 | ||
d8a8cfc7 PZ |
12988 | /* |
12989 | * Inherits an event group. | |
12990 | * | |
12991 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12992 | * This matches with perf_event_release_kernel() removing all child events. | |
12993 | * | |
12994 | * Returns: | |
12995 | * - 0 on success | |
12996 | * - <0 on error | |
12997 | */ | |
97dee4f3 PZ |
12998 | static int inherit_group(struct perf_event *parent_event, |
12999 | struct task_struct *parent, | |
13000 | struct perf_event_context *parent_ctx, | |
13001 | struct task_struct *child, | |
13002 | struct perf_event_context *child_ctx) | |
13003 | { | |
13004 | struct perf_event *leader; | |
13005 | struct perf_event *sub; | |
13006 | struct perf_event *child_ctr; | |
13007 | ||
13008 | leader = inherit_event(parent_event, parent, parent_ctx, | |
13009 | child, NULL, child_ctx); | |
13010 | if (IS_ERR(leader)) | |
13011 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
13012 | /* |
13013 | * @leader can be NULL here because of is_orphaned_event(). In this | |
13014 | * case inherit_event() will create individual events, similar to what | |
13015 | * perf_group_detach() would do anyway. | |
13016 | */ | |
edb39592 | 13017 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
13018 | child_ctr = inherit_event(sub, parent, parent_ctx, |
13019 | child, leader, child_ctx); | |
13020 | if (IS_ERR(child_ctr)) | |
13021 | return PTR_ERR(child_ctr); | |
f733c6b5 | 13022 | |
00496fe5 | 13023 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
13024 | !perf_get_aux_event(child_ctr, leader)) |
13025 | return -EINVAL; | |
97dee4f3 PZ |
13026 | } |
13027 | return 0; | |
889ff015 FW |
13028 | } |
13029 | ||
d8a8cfc7 PZ |
13030 | /* |
13031 | * Creates the child task context and tries to inherit the event-group. | |
13032 | * | |
13033 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
13034 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
13035 | * consistent with perf_event_release_kernel() removing all child events. | |
13036 | * | |
13037 | * Returns: | |
13038 | * - 0 on success | |
13039 | * - <0 on error | |
13040 | */ | |
889ff015 FW |
13041 | static int |
13042 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
13043 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 13044 | struct task_struct *child, int ctxn, |
2b26f0aa | 13045 | u64 clone_flags, int *inherited_all) |
889ff015 FW |
13046 | { |
13047 | int ret; | |
8dc85d54 | 13048 | struct perf_event_context *child_ctx; |
889ff015 | 13049 | |
2b26f0aa | 13050 | if (!event->attr.inherit || |
97ba62b2 ME |
13051 | (event->attr.inherit_thread && !(clone_flags & CLONE_THREAD)) || |
13052 | /* Do not inherit if sigtrap and signal handlers were cleared. */ | |
13053 | (event->attr.sigtrap && (clone_flags & CLONE_CLEAR_SIGHAND))) { | |
889ff015 FW |
13054 | *inherited_all = 0; |
13055 | return 0; | |
bbbee908 PZ |
13056 | } |
13057 | ||
fe4b04fa | 13058 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
13059 | if (!child_ctx) { |
13060 | /* | |
13061 | * This is executed from the parent task context, so | |
13062 | * inherit events that have been marked for cloning. | |
13063 | * First allocate and initialize a context for the | |
13064 | * child. | |
13065 | */ | |
734df5ab | 13066 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
13067 | if (!child_ctx) |
13068 | return -ENOMEM; | |
bbbee908 | 13069 | |
8dc85d54 | 13070 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
13071 | } |
13072 | ||
13073 | ret = inherit_group(event, parent, parent_ctx, | |
13074 | child, child_ctx); | |
13075 | ||
13076 | if (ret) | |
13077 | *inherited_all = 0; | |
13078 | ||
13079 | return ret; | |
bbbee908 PZ |
13080 | } |
13081 | ||
9b51f66d | 13082 | /* |
cdd6c482 | 13083 | * Initialize the perf_event context in task_struct |
9b51f66d | 13084 | */ |
2b26f0aa ME |
13085 | static int perf_event_init_context(struct task_struct *child, int ctxn, |
13086 | u64 clone_flags) | |
9b51f66d | 13087 | { |
889ff015 | 13088 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
13089 | struct perf_event_context *cloned_ctx; |
13090 | struct perf_event *event; | |
9b51f66d | 13091 | struct task_struct *parent = current; |
564c2b21 | 13092 | int inherited_all = 1; |
dddd3379 | 13093 | unsigned long flags; |
6ab423e0 | 13094 | int ret = 0; |
9b51f66d | 13095 | |
8dc85d54 | 13096 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
13097 | return 0; |
13098 | ||
ad3a37de | 13099 | /* |
25346b93 PM |
13100 | * If the parent's context is a clone, pin it so it won't get |
13101 | * swapped under us. | |
ad3a37de | 13102 | */ |
8dc85d54 | 13103 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
13104 | if (!parent_ctx) |
13105 | return 0; | |
25346b93 | 13106 | |
ad3a37de PM |
13107 | /* |
13108 | * No need to check if parent_ctx != NULL here; since we saw | |
13109 | * it non-NULL earlier, the only reason for it to become NULL | |
13110 | * is if we exit, and since we're currently in the middle of | |
13111 | * a fork we can't be exiting at the same time. | |
13112 | */ | |
ad3a37de | 13113 | |
9b51f66d IM |
13114 | /* |
13115 | * Lock the parent list. No need to lock the child - not PID | |
13116 | * hashed yet and not running, so nobody can access it. | |
13117 | */ | |
d859e29f | 13118 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
13119 | |
13120 | /* | |
13121 | * We dont have to disable NMIs - we are only looking at | |
13122 | * the list, not manipulating it: | |
13123 | */ | |
6e6804d2 | 13124 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 | 13125 | ret = inherit_task_group(event, parent, parent_ctx, |
2b26f0aa ME |
13126 | child, ctxn, clone_flags, |
13127 | &inherited_all); | |
889ff015 | 13128 | if (ret) |
e7cc4865 | 13129 | goto out_unlock; |
889ff015 | 13130 | } |
b93f7978 | 13131 | |
dddd3379 TG |
13132 | /* |
13133 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
13134 | * to allocations, but we need to prevent rotation because | |
13135 | * rotate_ctx() will change the list from interrupt context. | |
13136 | */ | |
13137 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
13138 | parent_ctx->rotate_disable = 1; | |
13139 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
13140 | ||
6e6804d2 | 13141 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 | 13142 | ret = inherit_task_group(event, parent, parent_ctx, |
2b26f0aa ME |
13143 | child, ctxn, clone_flags, |
13144 | &inherited_all); | |
889ff015 | 13145 | if (ret) |
e7cc4865 | 13146 | goto out_unlock; |
564c2b21 PM |
13147 | } |
13148 | ||
dddd3379 TG |
13149 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
13150 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 13151 | |
8dc85d54 | 13152 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 13153 | |
05cbaa28 | 13154 | if (child_ctx && inherited_all) { |
564c2b21 PM |
13155 | /* |
13156 | * Mark the child context as a clone of the parent | |
13157 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
13158 | * |
13159 | * Note that if the parent is a clone, the holding of | |
13160 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 13161 | */ |
c5ed5145 | 13162 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
13163 | if (cloned_ctx) { |
13164 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 13165 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
13166 | } else { |
13167 | child_ctx->parent_ctx = parent_ctx; | |
13168 | child_ctx->parent_gen = parent_ctx->generation; | |
13169 | } | |
13170 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
13171 | } |
13172 | ||
c5ed5145 | 13173 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 13174 | out_unlock: |
d859e29f | 13175 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 13176 | |
25346b93 | 13177 | perf_unpin_context(parent_ctx); |
fe4b04fa | 13178 | put_ctx(parent_ctx); |
ad3a37de | 13179 | |
6ab423e0 | 13180 | return ret; |
9b51f66d IM |
13181 | } |
13182 | ||
8dc85d54 PZ |
13183 | /* |
13184 | * Initialize the perf_event context in task_struct | |
13185 | */ | |
2b26f0aa | 13186 | int perf_event_init_task(struct task_struct *child, u64 clone_flags) |
8dc85d54 PZ |
13187 | { |
13188 | int ctxn, ret; | |
13189 | ||
8550d7cb ON |
13190 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
13191 | mutex_init(&child->perf_event_mutex); | |
13192 | INIT_LIST_HEAD(&child->perf_event_list); | |
13193 | ||
8dc85d54 | 13194 | for_each_task_context_nr(ctxn) { |
2b26f0aa | 13195 | ret = perf_event_init_context(child, ctxn, clone_flags); |
6c72e350 PZ |
13196 | if (ret) { |
13197 | perf_event_free_task(child); | |
8dc85d54 | 13198 | return ret; |
6c72e350 | 13199 | } |
8dc85d54 PZ |
13200 | } |
13201 | ||
13202 | return 0; | |
13203 | } | |
13204 | ||
220b140b PM |
13205 | static void __init perf_event_init_all_cpus(void) |
13206 | { | |
b28ab83c | 13207 | struct swevent_htable *swhash; |
220b140b | 13208 | int cpu; |
220b140b | 13209 | |
a63fbed7 TG |
13210 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
13211 | ||
220b140b | 13212 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
13213 | swhash = &per_cpu(swevent_htable, cpu); |
13214 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 13215 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
13216 | |
13217 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
13218 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 13219 | |
058fe1c0 DCC |
13220 | #ifdef CONFIG_CGROUP_PERF |
13221 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
13222 | #endif | |
a5398bff | 13223 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
13224 | } |
13225 | } | |
13226 | ||
d18bf422 | 13227 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 13228 | { |
108b02cf | 13229 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 13230 | |
b28ab83c | 13231 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 13232 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
13233 | struct swevent_hlist *hlist; |
13234 | ||
b28ab83c PZ |
13235 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
13236 | WARN_ON(!hlist); | |
13237 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 13238 | } |
b28ab83c | 13239 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
13240 | } |
13241 | ||
2965faa5 | 13242 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 13243 | static void __perf_event_exit_context(void *__info) |
0793a61d | 13244 | { |
108b02cf | 13245 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
13246 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
13247 | struct perf_event *event; | |
0793a61d | 13248 | |
fae3fde6 | 13249 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 13250 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 13251 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 13252 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 13253 | raw_spin_unlock(&ctx->lock); |
0793a61d | 13254 | } |
108b02cf PZ |
13255 | |
13256 | static void perf_event_exit_cpu_context(int cpu) | |
13257 | { | |
a63fbed7 | 13258 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
13259 | struct perf_event_context *ctx; |
13260 | struct pmu *pmu; | |
108b02cf | 13261 | |
a63fbed7 TG |
13262 | mutex_lock(&pmus_lock); |
13263 | list_for_each_entry(pmu, &pmus, entry) { | |
13264 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13265 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
13266 | |
13267 | mutex_lock(&ctx->mutex); | |
13268 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 13269 | cpuctx->online = 0; |
108b02cf PZ |
13270 | mutex_unlock(&ctx->mutex); |
13271 | } | |
a63fbed7 TG |
13272 | cpumask_clear_cpu(cpu, perf_online_mask); |
13273 | mutex_unlock(&pmus_lock); | |
108b02cf | 13274 | } |
00e16c3d TG |
13275 | #else |
13276 | ||
13277 | static void perf_event_exit_cpu_context(int cpu) { } | |
13278 | ||
13279 | #endif | |
108b02cf | 13280 | |
a63fbed7 TG |
13281 | int perf_event_init_cpu(unsigned int cpu) |
13282 | { | |
13283 | struct perf_cpu_context *cpuctx; | |
13284 | struct perf_event_context *ctx; | |
13285 | struct pmu *pmu; | |
13286 | ||
13287 | perf_swevent_init_cpu(cpu); | |
13288 | ||
13289 | mutex_lock(&pmus_lock); | |
13290 | cpumask_set_cpu(cpu, perf_online_mask); | |
13291 | list_for_each_entry(pmu, &pmus, entry) { | |
13292 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13293 | ctx = &cpuctx->ctx; | |
13294 | ||
13295 | mutex_lock(&ctx->mutex); | |
13296 | cpuctx->online = 1; | |
13297 | mutex_unlock(&ctx->mutex); | |
13298 | } | |
13299 | mutex_unlock(&pmus_lock); | |
13300 | ||
13301 | return 0; | |
13302 | } | |
13303 | ||
00e16c3d | 13304 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 13305 | { |
e3703f8c | 13306 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 13307 | return 0; |
0793a61d | 13308 | } |
0793a61d | 13309 | |
c277443c PZ |
13310 | static int |
13311 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
13312 | { | |
13313 | int cpu; | |
13314 | ||
13315 | for_each_online_cpu(cpu) | |
13316 | perf_event_exit_cpu(cpu); | |
13317 | ||
13318 | return NOTIFY_OK; | |
13319 | } | |
13320 | ||
13321 | /* | |
13322 | * Run the perf reboot notifier at the very last possible moment so that | |
13323 | * the generic watchdog code runs as long as possible. | |
13324 | */ | |
13325 | static struct notifier_block perf_reboot_notifier = { | |
13326 | .notifier_call = perf_reboot, | |
13327 | .priority = INT_MIN, | |
13328 | }; | |
13329 | ||
cdd6c482 | 13330 | void __init perf_event_init(void) |
0793a61d | 13331 | { |
3c502e7a JW |
13332 | int ret; |
13333 | ||
2e80a82a PZ |
13334 | idr_init(&pmu_idr); |
13335 | ||
220b140b | 13336 | perf_event_init_all_cpus(); |
b0a873eb | 13337 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
13338 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
13339 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
13340 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 13341 | perf_tp_register(); |
00e16c3d | 13342 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 13343 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
13344 | |
13345 | ret = init_hw_breakpoint(); | |
13346 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 13347 | |
bdacfaf2 NK |
13348 | perf_event_cache = KMEM_CACHE(perf_event, SLAB_PANIC); |
13349 | ||
b01c3a00 JO |
13350 | /* |
13351 | * Build time assertion that we keep the data_head at the intended | |
13352 | * location. IOW, validation we got the __reserved[] size right. | |
13353 | */ | |
13354 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
13355 | != 1024); | |
0793a61d | 13356 | } |
abe43400 | 13357 | |
fd979c01 CS |
13358 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
13359 | char *page) | |
13360 | { | |
13361 | struct perf_pmu_events_attr *pmu_attr = | |
13362 | container_of(attr, struct perf_pmu_events_attr, attr); | |
13363 | ||
13364 | if (pmu_attr->event_str) | |
13365 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
13366 | ||
13367 | return 0; | |
13368 | } | |
675965b0 | 13369 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 13370 | |
abe43400 PZ |
13371 | static int __init perf_event_sysfs_init(void) |
13372 | { | |
13373 | struct pmu *pmu; | |
13374 | int ret; | |
13375 | ||
13376 | mutex_lock(&pmus_lock); | |
13377 | ||
13378 | ret = bus_register(&pmu_bus); | |
13379 | if (ret) | |
13380 | goto unlock; | |
13381 | ||
13382 | list_for_each_entry(pmu, &pmus, entry) { | |
13383 | if (!pmu->name || pmu->type < 0) | |
13384 | continue; | |
13385 | ||
13386 | ret = pmu_dev_alloc(pmu); | |
13387 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
13388 | } | |
13389 | pmu_bus_running = 1; | |
13390 | ret = 0; | |
13391 | ||
13392 | unlock: | |
13393 | mutex_unlock(&pmus_lock); | |
13394 | ||
13395 | return ret; | |
13396 | } | |
13397 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
13398 | |
13399 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
13400 | static struct cgroup_subsys_state * |
13401 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
13402 | { |
13403 | struct perf_cgroup *jc; | |
e5d1367f | 13404 | |
1b15d055 | 13405 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
13406 | if (!jc) |
13407 | return ERR_PTR(-ENOMEM); | |
13408 | ||
e5d1367f SE |
13409 | jc->info = alloc_percpu(struct perf_cgroup_info); |
13410 | if (!jc->info) { | |
13411 | kfree(jc); | |
13412 | return ERR_PTR(-ENOMEM); | |
13413 | } | |
13414 | ||
e5d1367f SE |
13415 | return &jc->css; |
13416 | } | |
13417 | ||
eb95419b | 13418 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 13419 | { |
eb95419b TH |
13420 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
13421 | ||
e5d1367f SE |
13422 | free_percpu(jc->info); |
13423 | kfree(jc); | |
13424 | } | |
13425 | ||
96aaab68 NK |
13426 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
13427 | { | |
13428 | perf_event_cgroup(css->cgroup); | |
13429 | return 0; | |
13430 | } | |
13431 | ||
e5d1367f SE |
13432 | static int __perf_cgroup_move(void *info) |
13433 | { | |
13434 | struct task_struct *task = info; | |
ddaaf4e2 | 13435 | rcu_read_lock(); |
e5d1367f | 13436 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 13437 | rcu_read_unlock(); |
e5d1367f SE |
13438 | return 0; |
13439 | } | |
13440 | ||
1f7dd3e5 | 13441 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 13442 | { |
bb9d97b6 | 13443 | struct task_struct *task; |
1f7dd3e5 | 13444 | struct cgroup_subsys_state *css; |
bb9d97b6 | 13445 | |
1f7dd3e5 | 13446 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 13447 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
13448 | } |
13449 | ||
073219e9 | 13450 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
13451 | .css_alloc = perf_cgroup_css_alloc, |
13452 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 13453 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 13454 | .attach = perf_cgroup_attach, |
968ebff1 TH |
13455 | /* |
13456 | * Implicitly enable on dfl hierarchy so that perf events can | |
13457 | * always be filtered by cgroup2 path as long as perf_event | |
13458 | * controller is not mounted on a legacy hierarchy. | |
13459 | */ | |
13460 | .implicit_on_dfl = true, | |
8cfd8147 | 13461 | .threaded = true, |
e5d1367f SE |
13462 | }; |
13463 | #endif /* CONFIG_CGROUP_PERF */ |