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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 | |
135 | * @func: the function to be called | |
136 | * @info: the function call argument | |
137 | * | |
138 | * Calls the function @func on the remote cpu. | |
139 | * | |
140 | * returns: @func return value or -ENXIO when the cpu is offline | |
141 | */ | |
272325c4 | 142 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
143 | { |
144 | struct remote_function_call data = { | |
e7e7ee2e IM |
145 | .p = NULL, |
146 | .func = func, | |
147 | .info = info, | |
148 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
149 | }; |
150 | ||
151 | smp_call_function_single(cpu, remote_function, &data, 1); | |
152 | ||
153 | return data.ret; | |
154 | } | |
155 | ||
fae3fde6 PZ |
156 | static inline struct perf_cpu_context * |
157 | __get_cpu_context(struct perf_event_context *ctx) | |
158 | { | |
159 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
160 | } | |
161 | ||
162 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
163 | struct perf_event_context *ctx) | |
0017960f | 164 | { |
fae3fde6 PZ |
165 | raw_spin_lock(&cpuctx->ctx.lock); |
166 | if (ctx) | |
167 | raw_spin_lock(&ctx->lock); | |
168 | } | |
169 | ||
170 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
171 | struct perf_event_context *ctx) | |
172 | { | |
173 | if (ctx) | |
174 | raw_spin_unlock(&ctx->lock); | |
175 | raw_spin_unlock(&cpuctx->ctx.lock); | |
176 | } | |
177 | ||
63b6da39 PZ |
178 | #define TASK_TOMBSTONE ((void *)-1L) |
179 | ||
180 | static bool is_kernel_event(struct perf_event *event) | |
181 | { | |
f47c02c0 | 182 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
183 | } |
184 | ||
39a43640 PZ |
185 | /* |
186 | * On task ctx scheduling... | |
187 | * | |
188 | * When !ctx->nr_events a task context will not be scheduled. This means | |
189 | * we can disable the scheduler hooks (for performance) without leaving | |
190 | * pending task ctx state. | |
191 | * | |
192 | * This however results in two special cases: | |
193 | * | |
194 | * - removing the last event from a task ctx; this is relatively straight | |
195 | * forward and is done in __perf_remove_from_context. | |
196 | * | |
197 | * - adding the first event to a task ctx; this is tricky because we cannot | |
198 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
199 | * See perf_install_in_context(). | |
200 | * | |
39a43640 PZ |
201 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
202 | */ | |
203 | ||
fae3fde6 PZ |
204 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
205 | struct perf_event_context *, void *); | |
206 | ||
207 | struct event_function_struct { | |
208 | struct perf_event *event; | |
209 | event_f func; | |
210 | void *data; | |
211 | }; | |
212 | ||
213 | static int event_function(void *info) | |
214 | { | |
215 | struct event_function_struct *efs = info; | |
216 | struct perf_event *event = efs->event; | |
0017960f | 217 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
218 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
219 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 220 | int ret = 0; |
fae3fde6 | 221 | |
16444645 | 222 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 223 | |
63b6da39 | 224 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
225 | /* |
226 | * Since we do the IPI call without holding ctx->lock things can have | |
227 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
228 | */ |
229 | if (ctx->task) { | |
63b6da39 | 230 | if (ctx->task != current) { |
0da4cf3e | 231 | ret = -ESRCH; |
63b6da39 PZ |
232 | goto unlock; |
233 | } | |
fae3fde6 | 234 | |
fae3fde6 PZ |
235 | /* |
236 | * We only use event_function_call() on established contexts, | |
237 | * and event_function() is only ever called when active (or | |
238 | * rather, we'll have bailed in task_function_call() or the | |
239 | * above ctx->task != current test), therefore we must have | |
240 | * ctx->is_active here. | |
241 | */ | |
242 | WARN_ON_ONCE(!ctx->is_active); | |
243 | /* | |
244 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
245 | * match. | |
246 | */ | |
63b6da39 PZ |
247 | WARN_ON_ONCE(task_ctx != ctx); |
248 | } else { | |
249 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 250 | } |
63b6da39 | 251 | |
fae3fde6 | 252 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 253 | unlock: |
fae3fde6 PZ |
254 | perf_ctx_unlock(cpuctx, task_ctx); |
255 | ||
63b6da39 | 256 | return ret; |
fae3fde6 PZ |
257 | } |
258 | ||
fae3fde6 | 259 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
260 | { |
261 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 262 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
263 | struct event_function_struct efs = { |
264 | .event = event, | |
265 | .func = func, | |
266 | .data = data, | |
267 | }; | |
0017960f | 268 | |
c97f4736 PZ |
269 | if (!event->parent) { |
270 | /* | |
271 | * If this is a !child event, we must hold ctx::mutex to | |
c034f48e | 272 | * stabilize the event->ctx relation. See |
c97f4736 PZ |
273 | * perf_event_ctx_lock(). |
274 | */ | |
275 | lockdep_assert_held(&ctx->mutex); | |
276 | } | |
0017960f PZ |
277 | |
278 | if (!task) { | |
fae3fde6 | 279 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
280 | return; |
281 | } | |
282 | ||
63b6da39 PZ |
283 | if (task == TASK_TOMBSTONE) |
284 | return; | |
285 | ||
a096309b | 286 | again: |
fae3fde6 | 287 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
288 | return; |
289 | ||
290 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
291 | /* |
292 | * Reload the task pointer, it might have been changed by | |
293 | * a concurrent perf_event_context_sched_out(). | |
294 | */ | |
295 | task = ctx->task; | |
a096309b PZ |
296 | if (task == TASK_TOMBSTONE) { |
297 | raw_spin_unlock_irq(&ctx->lock); | |
298 | return; | |
0017960f | 299 | } |
a096309b PZ |
300 | if (ctx->is_active) { |
301 | raw_spin_unlock_irq(&ctx->lock); | |
302 | goto again; | |
303 | } | |
304 | func(event, NULL, ctx, data); | |
0017960f PZ |
305 | raw_spin_unlock_irq(&ctx->lock); |
306 | } | |
307 | ||
cca20946 PZ |
308 | /* |
309 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
310 | * are already disabled and we're on the right CPU. | |
311 | */ | |
312 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
313 | { | |
314 | struct perf_event_context *ctx = event->ctx; | |
315 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
316 | struct task_struct *task = READ_ONCE(ctx->task); | |
317 | struct perf_event_context *task_ctx = NULL; | |
318 | ||
16444645 | 319 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
320 | |
321 | if (task) { | |
322 | if (task == TASK_TOMBSTONE) | |
323 | return; | |
324 | ||
325 | task_ctx = ctx; | |
326 | } | |
327 | ||
328 | perf_ctx_lock(cpuctx, task_ctx); | |
329 | ||
330 | task = ctx->task; | |
331 | if (task == TASK_TOMBSTONE) | |
332 | goto unlock; | |
333 | ||
334 | if (task) { | |
335 | /* | |
336 | * We must be either inactive or active and the right task, | |
337 | * otherwise we're screwed, since we cannot IPI to somewhere | |
338 | * else. | |
339 | */ | |
340 | if (ctx->is_active) { | |
341 | if (WARN_ON_ONCE(task != current)) | |
342 | goto unlock; | |
343 | ||
344 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
345 | goto unlock; | |
346 | } | |
347 | } else { | |
348 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
349 | } | |
350 | ||
351 | func(event, cpuctx, ctx, data); | |
352 | unlock: | |
353 | perf_ctx_unlock(cpuctx, task_ctx); | |
354 | } | |
355 | ||
e5d1367f SE |
356 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
357 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
358 | PERF_FLAG_PID_CGROUP |\ |
359 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 360 | |
bce38cd5 SE |
361 | /* |
362 | * branch priv levels that need permission checks | |
363 | */ | |
364 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
365 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
366 | PERF_SAMPLE_BRANCH_HV) | |
367 | ||
0b3fcf17 SE |
368 | enum event_type_t { |
369 | EVENT_FLEXIBLE = 0x1, | |
370 | EVENT_PINNED = 0x2, | |
3cbaa590 | 371 | EVENT_TIME = 0x4, |
487f05e1 AS |
372 | /* see ctx_resched() for details */ |
373 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
374 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
375 | }; | |
376 | ||
e5d1367f SE |
377 | /* |
378 | * perf_sched_events : >0 events exist | |
379 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
380 | */ | |
9107c89e PZ |
381 | |
382 | static void perf_sched_delayed(struct work_struct *work); | |
383 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
384 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
385 | static DEFINE_MUTEX(perf_sched_mutex); | |
386 | static atomic_t perf_sched_count; | |
387 | ||
e5d1367f | 388 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
a5398bff | 389 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 390 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 391 | |
cdd6c482 IM |
392 | static atomic_t nr_mmap_events __read_mostly; |
393 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 394 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 395 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 396 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 397 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 398 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 399 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 400 | static atomic_t nr_cgroup_events __read_mostly; |
e17d43b9 | 401 | static atomic_t nr_text_poke_events __read_mostly; |
88a16a13 | 402 | static atomic_t nr_build_id_events __read_mostly; |
9ee318a7 | 403 | |
108b02cf PZ |
404 | static LIST_HEAD(pmus); |
405 | static DEFINE_MUTEX(pmus_lock); | |
406 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 407 | static cpumask_var_t perf_online_mask; |
bdacfaf2 | 408 | static struct kmem_cache *perf_event_cache; |
108b02cf | 409 | |
0764771d | 410 | /* |
cdd6c482 | 411 | * perf event paranoia level: |
0fbdea19 IM |
412 | * -1 - not paranoid at all |
413 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 414 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 415 | * 2 - disallow kernel profiling for unpriv |
0764771d | 416 | */ |
0161028b | 417 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 418 | |
20443384 FW |
419 | /* Minimum for 512 kiB + 1 user control page */ |
420 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
421 | |
422 | /* | |
cdd6c482 | 423 | * max perf event sample rate |
df58ab24 | 424 | */ |
14c63f17 DH |
425 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
426 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
427 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
428 | ||
429 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
430 | ||
431 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
432 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
433 | ||
d9494cb4 PZ |
434 | static int perf_sample_allowed_ns __read_mostly = |
435 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 436 | |
18ab2cd3 | 437 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
438 | { |
439 | u64 tmp = perf_sample_period_ns; | |
440 | ||
441 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
442 | tmp = div_u64(tmp, 100); |
443 | if (!tmp) | |
444 | tmp = 1; | |
445 | ||
446 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 447 | } |
163ec435 | 448 | |
8d5bce0c | 449 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 450 | |
163ec435 | 451 | int perf_proc_update_handler(struct ctl_table *table, int write, |
32927393 | 452 | void *buffer, size_t *lenp, loff_t *ppos) |
163ec435 | 453 | { |
1a51c5da SE |
454 | int ret; |
455 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
456 | /* |
457 | * If throttling is disabled don't allow the write: | |
458 | */ | |
1a51c5da | 459 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
460 | return -EINVAL; |
461 | ||
1a51c5da SE |
462 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
463 | if (ret || !write) | |
464 | return ret; | |
465 | ||
163ec435 | 466 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
467 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
468 | update_perf_cpu_limits(); | |
469 | ||
470 | return 0; | |
471 | } | |
472 | ||
473 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
474 | ||
475 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
32927393 | 476 | void *buffer, size_t *lenp, loff_t *ppos) |
14c63f17 | 477 | { |
1572e45a | 478 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
479 | |
480 | if (ret || !write) | |
481 | return ret; | |
482 | ||
b303e7c1 PZ |
483 | if (sysctl_perf_cpu_time_max_percent == 100 || |
484 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
485 | printk(KERN_WARNING |
486 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
487 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
488 | } else { | |
489 | update_perf_cpu_limits(); | |
490 | } | |
163ec435 PZ |
491 | |
492 | return 0; | |
493 | } | |
1ccd1549 | 494 | |
14c63f17 DH |
495 | /* |
496 | * perf samples are done in some very critical code paths (NMIs). | |
497 | * If they take too much CPU time, the system can lock up and not | |
498 | * get any real work done. This will drop the sample rate when | |
499 | * we detect that events are taking too long. | |
500 | */ | |
501 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 502 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 503 | |
91a612ee PZ |
504 | static u64 __report_avg; |
505 | static u64 __report_allowed; | |
506 | ||
6a02ad66 | 507 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 508 | { |
0d87d7ec | 509 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
510 | "perf: interrupt took too long (%lld > %lld), lowering " |
511 | "kernel.perf_event_max_sample_rate to %d\n", | |
512 | __report_avg, __report_allowed, | |
513 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
514 | } |
515 | ||
516 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
517 | ||
518 | void perf_sample_event_took(u64 sample_len_ns) | |
519 | { | |
91a612ee PZ |
520 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
521 | u64 running_len; | |
522 | u64 avg_len; | |
523 | u32 max; | |
14c63f17 | 524 | |
91a612ee | 525 | if (max_len == 0) |
14c63f17 DH |
526 | return; |
527 | ||
91a612ee PZ |
528 | /* Decay the counter by 1 average sample. */ |
529 | running_len = __this_cpu_read(running_sample_length); | |
530 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
531 | running_len += sample_len_ns; | |
532 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
533 | |
534 | /* | |
91a612ee PZ |
535 | * Note: this will be biased artifically low until we have |
536 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
537 | * from having to maintain a count. |
538 | */ | |
91a612ee PZ |
539 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
540 | if (avg_len <= max_len) | |
14c63f17 DH |
541 | return; |
542 | ||
91a612ee PZ |
543 | __report_avg = avg_len; |
544 | __report_allowed = max_len; | |
14c63f17 | 545 | |
91a612ee PZ |
546 | /* |
547 | * Compute a throttle threshold 25% below the current duration. | |
548 | */ | |
549 | avg_len += avg_len / 4; | |
550 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
551 | if (avg_len < max) | |
552 | max /= (u32)avg_len; | |
553 | else | |
554 | max = 1; | |
14c63f17 | 555 | |
91a612ee PZ |
556 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
557 | WRITE_ONCE(max_samples_per_tick, max); | |
558 | ||
559 | sysctl_perf_event_sample_rate = max * HZ; | |
560 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 561 | |
cd578abb | 562 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 563 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 564 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 565 | __report_avg, __report_allowed, |
cd578abb PZ |
566 | sysctl_perf_event_sample_rate); |
567 | } | |
14c63f17 DH |
568 | } |
569 | ||
cdd6c482 | 570 | static atomic64_t perf_event_id; |
a96bbc16 | 571 | |
0b3fcf17 SE |
572 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
573 | enum event_type_t event_type); | |
574 | ||
575 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
576 | enum event_type_t event_type, |
577 | struct task_struct *task); | |
578 | ||
579 | static void update_context_time(struct perf_event_context *ctx); | |
580 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 581 | |
cdd6c482 | 582 | void __weak perf_event_print_debug(void) { } |
0793a61d | 583 | |
84c79910 | 584 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 585 | { |
84c79910 | 586 | return "pmu"; |
0793a61d TG |
587 | } |
588 | ||
0b3fcf17 SE |
589 | static inline u64 perf_clock(void) |
590 | { | |
591 | return local_clock(); | |
592 | } | |
593 | ||
34f43927 PZ |
594 | static inline u64 perf_event_clock(struct perf_event *event) |
595 | { | |
596 | return event->clock(); | |
597 | } | |
598 | ||
0d3d73aa PZ |
599 | /* |
600 | * State based event timekeeping... | |
601 | * | |
602 | * The basic idea is to use event->state to determine which (if any) time | |
603 | * fields to increment with the current delta. This means we only need to | |
604 | * update timestamps when we change state or when they are explicitly requested | |
605 | * (read). | |
606 | * | |
607 | * Event groups make things a little more complicated, but not terribly so. The | |
608 | * rules for a group are that if the group leader is OFF the entire group is | |
609 | * OFF, irrespecive of what the group member states are. This results in | |
610 | * __perf_effective_state(). | |
611 | * | |
612 | * A futher ramification is that when a group leader flips between OFF and | |
613 | * !OFF, we need to update all group member times. | |
614 | * | |
615 | * | |
616 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
617 | * need to make sure the relevant context time is updated before we try and | |
618 | * update our timestamps. | |
619 | */ | |
620 | ||
621 | static __always_inline enum perf_event_state | |
622 | __perf_effective_state(struct perf_event *event) | |
623 | { | |
624 | struct perf_event *leader = event->group_leader; | |
625 | ||
626 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
627 | return leader->state; | |
628 | ||
629 | return event->state; | |
630 | } | |
631 | ||
632 | static __always_inline void | |
633 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
634 | { | |
635 | enum perf_event_state state = __perf_effective_state(event); | |
636 | u64 delta = now - event->tstamp; | |
637 | ||
638 | *enabled = event->total_time_enabled; | |
639 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
640 | *enabled += delta; | |
641 | ||
642 | *running = event->total_time_running; | |
643 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
644 | *running += delta; | |
645 | } | |
646 | ||
647 | static void perf_event_update_time(struct perf_event *event) | |
648 | { | |
649 | u64 now = perf_event_time(event); | |
650 | ||
651 | __perf_update_times(event, now, &event->total_time_enabled, | |
652 | &event->total_time_running); | |
653 | event->tstamp = now; | |
654 | } | |
655 | ||
656 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
657 | { | |
658 | struct perf_event *sibling; | |
659 | ||
edb39592 | 660 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
661 | perf_event_update_time(sibling); |
662 | } | |
663 | ||
664 | static void | |
665 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
666 | { | |
667 | if (event->state == state) | |
668 | return; | |
669 | ||
670 | perf_event_update_time(event); | |
671 | /* | |
672 | * If a group leader gets enabled/disabled all its siblings | |
673 | * are affected too. | |
674 | */ | |
675 | if ((event->state < 0) ^ (state < 0)) | |
676 | perf_event_update_sibling_time(event); | |
677 | ||
678 | WRITE_ONCE(event->state, state); | |
679 | } | |
680 | ||
e5d1367f SE |
681 | #ifdef CONFIG_CGROUP_PERF |
682 | ||
e5d1367f SE |
683 | static inline bool |
684 | perf_cgroup_match(struct perf_event *event) | |
685 | { | |
686 | struct perf_event_context *ctx = event->ctx; | |
687 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
688 | ||
ef824fa1 TH |
689 | /* @event doesn't care about cgroup */ |
690 | if (!event->cgrp) | |
691 | return true; | |
692 | ||
693 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
694 | if (!cpuctx->cgrp) | |
695 | return false; | |
696 | ||
697 | /* | |
698 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
699 | * also enabled for all its descendant cgroups. If @cpuctx's | |
700 | * cgroup is a descendant of @event's (the test covers identity | |
701 | * case), it's a match. | |
702 | */ | |
703 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
704 | event->cgrp->css.cgroup); | |
e5d1367f SE |
705 | } |
706 | ||
e5d1367f SE |
707 | static inline void perf_detach_cgroup(struct perf_event *event) |
708 | { | |
4e2ba650 | 709 | css_put(&event->cgrp->css); |
e5d1367f SE |
710 | event->cgrp = NULL; |
711 | } | |
712 | ||
713 | static inline int is_cgroup_event(struct perf_event *event) | |
714 | { | |
715 | return event->cgrp != NULL; | |
716 | } | |
717 | ||
718 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
719 | { | |
720 | struct perf_cgroup_info *t; | |
721 | ||
722 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
723 | return t->time; | |
724 | } | |
725 | ||
726 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
727 | { | |
728 | struct perf_cgroup_info *info; | |
729 | u64 now; | |
730 | ||
731 | now = perf_clock(); | |
732 | ||
733 | info = this_cpu_ptr(cgrp->info); | |
734 | ||
735 | info->time += now - info->timestamp; | |
736 | info->timestamp = now; | |
737 | } | |
738 | ||
739 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
740 | { | |
c917e0f2 SL |
741 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
742 | struct cgroup_subsys_state *css; | |
743 | ||
744 | if (cgrp) { | |
745 | for (css = &cgrp->css; css; css = css->parent) { | |
746 | cgrp = container_of(css, struct perf_cgroup, css); | |
747 | __update_cgrp_time(cgrp); | |
748 | } | |
749 | } | |
e5d1367f SE |
750 | } |
751 | ||
752 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
753 | { | |
3f7cce3c SE |
754 | struct perf_cgroup *cgrp; |
755 | ||
e5d1367f | 756 | /* |
3f7cce3c SE |
757 | * ensure we access cgroup data only when needed and |
758 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 759 | */ |
3f7cce3c | 760 | if (!is_cgroup_event(event)) |
e5d1367f SE |
761 | return; |
762 | ||
614e4c4e | 763 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
764 | /* |
765 | * Do not update time when cgroup is not active | |
766 | */ | |
28fa741c | 767 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 768 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
769 | } |
770 | ||
771 | static inline void | |
3f7cce3c SE |
772 | perf_cgroup_set_timestamp(struct task_struct *task, |
773 | struct perf_event_context *ctx) | |
e5d1367f SE |
774 | { |
775 | struct perf_cgroup *cgrp; | |
776 | struct perf_cgroup_info *info; | |
c917e0f2 | 777 | struct cgroup_subsys_state *css; |
e5d1367f | 778 | |
3f7cce3c SE |
779 | /* |
780 | * ctx->lock held by caller | |
781 | * ensure we do not access cgroup data | |
782 | * unless we have the cgroup pinned (css_get) | |
783 | */ | |
784 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
785 | return; |
786 | ||
614e4c4e | 787 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
788 | |
789 | for (css = &cgrp->css; css; css = css->parent) { | |
790 | cgrp = container_of(css, struct perf_cgroup, css); | |
791 | info = this_cpu_ptr(cgrp->info); | |
792 | info->timestamp = ctx->timestamp; | |
793 | } | |
e5d1367f SE |
794 | } |
795 | ||
058fe1c0 DCC |
796 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
797 | ||
e5d1367f SE |
798 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
799 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
800 | ||
801 | /* | |
802 | * reschedule events based on the cgroup constraint of task. | |
803 | * | |
804 | * mode SWOUT : schedule out everything | |
805 | * mode SWIN : schedule in based on cgroup for next | |
806 | */ | |
18ab2cd3 | 807 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
808 | { |
809 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 810 | struct list_head *list; |
e5d1367f SE |
811 | unsigned long flags; |
812 | ||
813 | /* | |
058fe1c0 DCC |
814 | * Disable interrupts and preemption to avoid this CPU's |
815 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
816 | */ |
817 | local_irq_save(flags); | |
818 | ||
058fe1c0 DCC |
819 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
820 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
821 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 822 | |
058fe1c0 DCC |
823 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
824 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 825 | |
058fe1c0 DCC |
826 | if (mode & PERF_CGROUP_SWOUT) { |
827 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
828 | /* | |
829 | * must not be done before ctxswout due | |
830 | * to event_filter_match() in event_sched_out() | |
831 | */ | |
832 | cpuctx->cgrp = NULL; | |
833 | } | |
e5d1367f | 834 | |
058fe1c0 DCC |
835 | if (mode & PERF_CGROUP_SWIN) { |
836 | WARN_ON_ONCE(cpuctx->cgrp); | |
837 | /* | |
838 | * set cgrp before ctxsw in to allow | |
839 | * event_filter_match() to not have to pass | |
840 | * task around | |
841 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
842 | * because cgorup events are only per-cpu | |
843 | */ | |
844 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
845 | &cpuctx->ctx); | |
846 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 847 | } |
058fe1c0 DCC |
848 | perf_pmu_enable(cpuctx->ctx.pmu); |
849 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
850 | } |
851 | ||
e5d1367f SE |
852 | local_irq_restore(flags); |
853 | } | |
854 | ||
a8d757ef SE |
855 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
856 | struct task_struct *next) | |
e5d1367f | 857 | { |
a8d757ef SE |
858 | struct perf_cgroup *cgrp1; |
859 | struct perf_cgroup *cgrp2 = NULL; | |
860 | ||
ddaaf4e2 | 861 | rcu_read_lock(); |
a8d757ef SE |
862 | /* |
863 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
864 | * we do not need to pass the ctx here because we know |
865 | * we are holding the rcu lock | |
a8d757ef | 866 | */ |
614e4c4e | 867 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 868 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
869 | |
870 | /* | |
871 | * only schedule out current cgroup events if we know | |
872 | * that we are switching to a different cgroup. Otherwise, | |
873 | * do no touch the cgroup events. | |
874 | */ | |
875 | if (cgrp1 != cgrp2) | |
876 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
877 | |
878 | rcu_read_unlock(); | |
e5d1367f SE |
879 | } |
880 | ||
a8d757ef SE |
881 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
882 | struct task_struct *task) | |
e5d1367f | 883 | { |
a8d757ef SE |
884 | struct perf_cgroup *cgrp1; |
885 | struct perf_cgroup *cgrp2 = NULL; | |
886 | ||
ddaaf4e2 | 887 | rcu_read_lock(); |
a8d757ef SE |
888 | /* |
889 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
890 | * we do not need to pass the ctx here because we know |
891 | * we are holding the rcu lock | |
a8d757ef | 892 | */ |
614e4c4e | 893 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 894 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
895 | |
896 | /* | |
897 | * only need to schedule in cgroup events if we are changing | |
898 | * cgroup during ctxsw. Cgroup events were not scheduled | |
899 | * out of ctxsw out if that was not the case. | |
900 | */ | |
901 | if (cgrp1 != cgrp2) | |
902 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
903 | |
904 | rcu_read_unlock(); | |
e5d1367f SE |
905 | } |
906 | ||
c2283c93 IR |
907 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
908 | struct cgroup_subsys_state *css) | |
909 | { | |
910 | struct perf_cpu_context *cpuctx; | |
911 | struct perf_event **storage; | |
912 | int cpu, heap_size, ret = 0; | |
913 | ||
914 | /* | |
915 | * Allow storage to have sufficent space for an iterator for each | |
916 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
917 | */ | |
918 | for (heap_size = 1; css; css = css->parent) | |
919 | heap_size++; | |
920 | ||
921 | for_each_possible_cpu(cpu) { | |
922 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
923 | if (heap_size <= cpuctx->heap_size) | |
924 | continue; | |
925 | ||
926 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
927 | GFP_KERNEL, cpu_to_node(cpu)); | |
928 | if (!storage) { | |
929 | ret = -ENOMEM; | |
930 | break; | |
931 | } | |
932 | ||
933 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
934 | if (cpuctx->heap_size < heap_size) { | |
935 | swap(cpuctx->heap, storage); | |
936 | if (storage == cpuctx->heap_default) | |
937 | storage = NULL; | |
938 | cpuctx->heap_size = heap_size; | |
939 | } | |
940 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
941 | ||
942 | kfree(storage); | |
943 | } | |
944 | ||
945 | return ret; | |
946 | } | |
947 | ||
e5d1367f SE |
948 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
949 | struct perf_event_attr *attr, | |
950 | struct perf_event *group_leader) | |
951 | { | |
952 | struct perf_cgroup *cgrp; | |
953 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
954 | struct fd f = fdget(fd); |
955 | int ret = 0; | |
e5d1367f | 956 | |
2903ff01 | 957 | if (!f.file) |
e5d1367f SE |
958 | return -EBADF; |
959 | ||
b583043e | 960 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 961 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
962 | if (IS_ERR(css)) { |
963 | ret = PTR_ERR(css); | |
964 | goto out; | |
965 | } | |
e5d1367f | 966 | |
c2283c93 IR |
967 | ret = perf_cgroup_ensure_storage(event, css); |
968 | if (ret) | |
969 | goto out; | |
970 | ||
e5d1367f SE |
971 | cgrp = container_of(css, struct perf_cgroup, css); |
972 | event->cgrp = cgrp; | |
973 | ||
974 | /* | |
975 | * all events in a group must monitor | |
976 | * the same cgroup because a task belongs | |
977 | * to only one perf cgroup at a time | |
978 | */ | |
979 | if (group_leader && group_leader->cgrp != cgrp) { | |
980 | perf_detach_cgroup(event); | |
981 | ret = -EINVAL; | |
e5d1367f | 982 | } |
3db272c0 | 983 | out: |
2903ff01 | 984 | fdput(f); |
e5d1367f SE |
985 | return ret; |
986 | } | |
987 | ||
988 | static inline void | |
989 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
990 | { | |
991 | struct perf_cgroup_info *t; | |
992 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
993 | event->shadow_ctx_time = now - t->timestamp; | |
994 | } | |
995 | ||
db4a8356 | 996 | static inline void |
33238c50 | 997 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
998 | { |
999 | struct perf_cpu_context *cpuctx; | |
1000 | ||
1001 | if (!is_cgroup_event(event)) | |
1002 | return; | |
1003 | ||
db4a8356 DCC |
1004 | /* |
1005 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1006 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1007 | */ |
07c59729 | 1008 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1009 | |
1010 | /* | |
1011 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1012 | * matching the event's cgroup, we must do this for every new event, | |
1013 | * because if the first would mismatch, the second would not try again | |
1014 | * and we would leave cpuctx->cgrp unset. | |
1015 | */ | |
33238c50 | 1016 | if (ctx->is_active && !cpuctx->cgrp) { |
be96b316 TH |
1017 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1018 | ||
be96b316 TH |
1019 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1020 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1021 | } |
33801b94 | 1022 | |
33238c50 | 1023 | if (ctx->nr_cgroups++) |
33801b94 | 1024 | return; |
33238c50 PZ |
1025 | |
1026 | list_add(&cpuctx->cgrp_cpuctx_entry, | |
1027 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
1028 | } | |
1029 | ||
1030 | static inline void | |
1031 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1032 | { | |
1033 | struct perf_cpu_context *cpuctx; | |
1034 | ||
1035 | if (!is_cgroup_event(event)) | |
33801b94 | 1036 | return; |
1037 | ||
33238c50 PZ |
1038 | /* |
1039 | * Because cgroup events are always per-cpu events, | |
1040 | * @ctx == &cpuctx->ctx. | |
1041 | */ | |
1042 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); | |
1043 | ||
1044 | if (--ctx->nr_cgroups) | |
1045 | return; | |
1046 | ||
1047 | if (ctx->is_active && cpuctx->cgrp) | |
33801b94 | 1048 | cpuctx->cgrp = NULL; |
1049 | ||
33238c50 | 1050 | list_del(&cpuctx->cgrp_cpuctx_entry); |
db4a8356 DCC |
1051 | } |
1052 | ||
e5d1367f SE |
1053 | #else /* !CONFIG_CGROUP_PERF */ |
1054 | ||
1055 | static inline bool | |
1056 | perf_cgroup_match(struct perf_event *event) | |
1057 | { | |
1058 | return true; | |
1059 | } | |
1060 | ||
1061 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1062 | {} | |
1063 | ||
1064 | static inline int is_cgroup_event(struct perf_event *event) | |
1065 | { | |
1066 | return 0; | |
1067 | } | |
1068 | ||
e5d1367f SE |
1069 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1070 | { | |
1071 | } | |
1072 | ||
1073 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1074 | { | |
1075 | } | |
1076 | ||
a8d757ef SE |
1077 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1078 | struct task_struct *next) | |
e5d1367f SE |
1079 | { |
1080 | } | |
1081 | ||
a8d757ef SE |
1082 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1083 | struct task_struct *task) | |
e5d1367f SE |
1084 | { |
1085 | } | |
1086 | ||
1087 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1088 | struct perf_event_attr *attr, | |
1089 | struct perf_event *group_leader) | |
1090 | { | |
1091 | return -EINVAL; | |
1092 | } | |
1093 | ||
1094 | static inline void | |
3f7cce3c SE |
1095 | perf_cgroup_set_timestamp(struct task_struct *task, |
1096 | struct perf_event_context *ctx) | |
e5d1367f SE |
1097 | { |
1098 | } | |
1099 | ||
d00dbd29 | 1100 | static inline void |
e5d1367f SE |
1101 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1102 | { | |
1103 | } | |
1104 | ||
1105 | static inline void | |
1106 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1107 | { | |
1108 | } | |
1109 | ||
1110 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1111 | { | |
1112 | return 0; | |
1113 | } | |
1114 | ||
db4a8356 | 1115 | static inline void |
33238c50 | 1116 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1117 | { |
1118 | } | |
1119 | ||
33238c50 PZ |
1120 | static inline void |
1121 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1122 | { | |
1123 | } | |
e5d1367f SE |
1124 | #endif |
1125 | ||
9e630205 SE |
1126 | /* |
1127 | * set default to be dependent on timer tick just | |
1128 | * like original code | |
1129 | */ | |
1130 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1131 | /* | |
8a1115ff | 1132 | * function must be called with interrupts disabled |
9e630205 | 1133 | */ |
272325c4 | 1134 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1135 | { |
1136 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1137 | bool rotations; |
9e630205 | 1138 | |
16444645 | 1139 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1140 | |
1141 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1142 | rotations = perf_rotate_context(cpuctx); |
1143 | ||
4cfafd30 PZ |
1144 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1145 | if (rotations) | |
9e630205 | 1146 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1147 | else |
1148 | cpuctx->hrtimer_active = 0; | |
1149 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1150 | |
4cfafd30 | 1151 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1152 | } |
1153 | ||
272325c4 | 1154 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1155 | { |
272325c4 | 1156 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1157 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1158 | u64 interval; |
9e630205 SE |
1159 | |
1160 | /* no multiplexing needed for SW PMU */ | |
1161 | if (pmu->task_ctx_nr == perf_sw_context) | |
1162 | return; | |
1163 | ||
62b85639 SE |
1164 | /* |
1165 | * check default is sane, if not set then force to | |
1166 | * default interval (1/tick) | |
1167 | */ | |
272325c4 PZ |
1168 | interval = pmu->hrtimer_interval_ms; |
1169 | if (interval < 1) | |
1170 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1171 | |
272325c4 | 1172 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1173 | |
4cfafd30 | 1174 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1175 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1176 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1177 | } |
1178 | ||
272325c4 | 1179 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1180 | { |
272325c4 | 1181 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1182 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1183 | unsigned long flags; |
9e630205 SE |
1184 | |
1185 | /* not for SW PMU */ | |
1186 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1187 | return 0; |
9e630205 | 1188 | |
4cfafd30 PZ |
1189 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1190 | if (!cpuctx->hrtimer_active) { | |
1191 | cpuctx->hrtimer_active = 1; | |
1192 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1193 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1194 | } |
1195 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1196 | |
272325c4 | 1197 | return 0; |
9e630205 SE |
1198 | } |
1199 | ||
33696fc0 | 1200 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1201 | { |
33696fc0 PZ |
1202 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1203 | if (!(*count)++) | |
1204 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1205 | } |
9e35ad38 | 1206 | |
33696fc0 | 1207 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1208 | { |
33696fc0 PZ |
1209 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1210 | if (!--(*count)) | |
1211 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1212 | } |
9e35ad38 | 1213 | |
2fde4f94 | 1214 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1215 | |
1216 | /* | |
2fde4f94 MR |
1217 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1218 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1219 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1220 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1221 | */ |
2fde4f94 | 1222 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1223 | { |
2fde4f94 | 1224 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1225 | |
16444645 | 1226 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1227 | |
2fde4f94 MR |
1228 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1229 | ||
1230 | list_add(&ctx->active_ctx_list, head); | |
1231 | } | |
1232 | ||
1233 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1234 | { | |
16444645 | 1235 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1236 | |
1237 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1238 | ||
1239 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1240 | } |
9e35ad38 | 1241 | |
cdd6c482 | 1242 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1243 | { |
8c94abbb | 1244 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1245 | } |
1246 | ||
ff9ff926 KL |
1247 | static void *alloc_task_ctx_data(struct pmu *pmu) |
1248 | { | |
217c2a63 KL |
1249 | if (pmu->task_ctx_cache) |
1250 | return kmem_cache_zalloc(pmu->task_ctx_cache, GFP_KERNEL); | |
1251 | ||
5a09928d | 1252 | return NULL; |
ff9ff926 KL |
1253 | } |
1254 | ||
1255 | static void free_task_ctx_data(struct pmu *pmu, void *task_ctx_data) | |
1256 | { | |
217c2a63 KL |
1257 | if (pmu->task_ctx_cache && task_ctx_data) |
1258 | kmem_cache_free(pmu->task_ctx_cache, task_ctx_data); | |
ff9ff926 KL |
1259 | } |
1260 | ||
4af57ef2 YZ |
1261 | static void free_ctx(struct rcu_head *head) |
1262 | { | |
1263 | struct perf_event_context *ctx; | |
1264 | ||
1265 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
ff9ff926 | 1266 | free_task_ctx_data(ctx->pmu, ctx->task_ctx_data); |
4af57ef2 YZ |
1267 | kfree(ctx); |
1268 | } | |
1269 | ||
cdd6c482 | 1270 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1271 | { |
8c94abbb | 1272 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1273 | if (ctx->parent_ctx) |
1274 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1275 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1276 | put_task_struct(ctx->task); |
4af57ef2 | 1277 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1278 | } |
a63eaf34 PM |
1279 | } |
1280 | ||
f63a8daa PZ |
1281 | /* |
1282 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1283 | * perf_pmu_migrate_context() we need some magic. | |
1284 | * | |
1285 | * Those places that change perf_event::ctx will hold both | |
1286 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1287 | * | |
8b10c5e2 PZ |
1288 | * Lock ordering is by mutex address. There are two other sites where |
1289 | * perf_event_context::mutex nests and those are: | |
1290 | * | |
1291 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1292 | * perf_event_exit_event() |
1293 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1294 | * |
1295 | * - perf_event_init_context() [ parent, 0 ] | |
1296 | * inherit_task_group() | |
1297 | * inherit_group() | |
1298 | * inherit_event() | |
1299 | * perf_event_alloc() | |
1300 | * perf_init_event() | |
1301 | * perf_try_init_event() [ child , 1 ] | |
1302 | * | |
1303 | * While it appears there is an obvious deadlock here -- the parent and child | |
1304 | * nesting levels are inverted between the two. This is in fact safe because | |
1305 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1306 | * spawning task cannot (yet) exit. | |
1307 | * | |
c034f48e | 1308 | * But remember that these are parent<->child context relations, and |
8b10c5e2 PZ |
1309 | * migration does not affect children, therefore these two orderings should not |
1310 | * interact. | |
f63a8daa PZ |
1311 | * |
1312 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1313 | * because the sys_perf_event_open() case will install a new event and break | |
1314 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1315 | * concerned with cpuctx and that doesn't have children. | |
1316 | * | |
1317 | * The places that change perf_event::ctx will issue: | |
1318 | * | |
1319 | * perf_remove_from_context(); | |
1320 | * synchronize_rcu(); | |
1321 | * perf_install_in_context(); | |
1322 | * | |
1323 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1324 | * quiesce the event, after which we can install it in the new location. This | |
1325 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1326 | * while in transit. Therefore all such accessors should also acquire | |
1327 | * perf_event_context::mutex to serialize against this. | |
1328 | * | |
1329 | * However; because event->ctx can change while we're waiting to acquire | |
1330 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1331 | * function. | |
1332 | * | |
1333 | * Lock order: | |
f7cfd871 | 1334 | * exec_update_lock |
f63a8daa PZ |
1335 | * task_struct::perf_event_mutex |
1336 | * perf_event_context::mutex | |
f63a8daa | 1337 | * perf_event::child_mutex; |
07c4a776 | 1338 | * perf_event_context::lock |
f63a8daa | 1339 | * perf_event::mmap_mutex |
c1e8d7c6 | 1340 | * mmap_lock |
18736eef | 1341 | * perf_addr_filters_head::lock |
82d94856 PZ |
1342 | * |
1343 | * cpu_hotplug_lock | |
1344 | * pmus_lock | |
1345 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1346 | */ |
a83fe28e PZ |
1347 | static struct perf_event_context * |
1348 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1349 | { |
1350 | struct perf_event_context *ctx; | |
1351 | ||
1352 | again: | |
1353 | rcu_read_lock(); | |
6aa7de05 | 1354 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1355 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1356 | rcu_read_unlock(); |
1357 | goto again; | |
1358 | } | |
1359 | rcu_read_unlock(); | |
1360 | ||
a83fe28e | 1361 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1362 | if (event->ctx != ctx) { |
1363 | mutex_unlock(&ctx->mutex); | |
1364 | put_ctx(ctx); | |
1365 | goto again; | |
1366 | } | |
1367 | ||
1368 | return ctx; | |
1369 | } | |
1370 | ||
a83fe28e PZ |
1371 | static inline struct perf_event_context * |
1372 | perf_event_ctx_lock(struct perf_event *event) | |
1373 | { | |
1374 | return perf_event_ctx_lock_nested(event, 0); | |
1375 | } | |
1376 | ||
f63a8daa PZ |
1377 | static void perf_event_ctx_unlock(struct perf_event *event, |
1378 | struct perf_event_context *ctx) | |
1379 | { | |
1380 | mutex_unlock(&ctx->mutex); | |
1381 | put_ctx(ctx); | |
1382 | } | |
1383 | ||
211de6eb PZ |
1384 | /* |
1385 | * This must be done under the ctx->lock, such as to serialize against | |
1386 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1387 | * calling scheduler related locks and ctx->lock nests inside those. | |
1388 | */ | |
1389 | static __must_check struct perf_event_context * | |
1390 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1391 | { |
211de6eb PZ |
1392 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1393 | ||
1394 | lockdep_assert_held(&ctx->lock); | |
1395 | ||
1396 | if (parent_ctx) | |
71a851b4 | 1397 | ctx->parent_ctx = NULL; |
5a3126d4 | 1398 | ctx->generation++; |
211de6eb PZ |
1399 | |
1400 | return parent_ctx; | |
71a851b4 PZ |
1401 | } |
1402 | ||
1d953111 ON |
1403 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1404 | enum pid_type type) | |
6844c09d | 1405 | { |
1d953111 | 1406 | u32 nr; |
6844c09d ACM |
1407 | /* |
1408 | * only top level events have the pid namespace they were created in | |
1409 | */ | |
1410 | if (event->parent) | |
1411 | event = event->parent; | |
1412 | ||
1d953111 ON |
1413 | nr = __task_pid_nr_ns(p, type, event->ns); |
1414 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1415 | if (!nr && !pid_alive(p)) | |
1416 | nr = -1; | |
1417 | return nr; | |
6844c09d ACM |
1418 | } |
1419 | ||
1d953111 | 1420 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1421 | { |
6883f81a | 1422 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1423 | } |
6844c09d | 1424 | |
1d953111 ON |
1425 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1426 | { | |
1427 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1428 | } |
1429 | ||
7f453c24 | 1430 | /* |
cdd6c482 | 1431 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1432 | * to userspace. |
1433 | */ | |
cdd6c482 | 1434 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1435 | { |
cdd6c482 | 1436 | u64 id = event->id; |
7f453c24 | 1437 | |
cdd6c482 IM |
1438 | if (event->parent) |
1439 | id = event->parent->id; | |
7f453c24 PZ |
1440 | |
1441 | return id; | |
1442 | } | |
1443 | ||
25346b93 | 1444 | /* |
cdd6c482 | 1445 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1446 | * |
c034f48e | 1447 | * This has to cope with the fact that until it is locked, |
25346b93 PM |
1448 | * the context could get moved to another task. |
1449 | */ | |
cdd6c482 | 1450 | static struct perf_event_context * |
8dc85d54 | 1451 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1452 | { |
cdd6c482 | 1453 | struct perf_event_context *ctx; |
25346b93 | 1454 | |
9ed6060d | 1455 | retry: |
058ebd0e PZ |
1456 | /* |
1457 | * One of the few rules of preemptible RCU is that one cannot do | |
1458 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1459 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1460 | * rcu_read_unlock_special(). |
1461 | * | |
1462 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1463 | * side critical section has interrupts disabled. |
058ebd0e | 1464 | */ |
2fd59077 | 1465 | local_irq_save(*flags); |
058ebd0e | 1466 | rcu_read_lock(); |
8dc85d54 | 1467 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1468 | if (ctx) { |
1469 | /* | |
1470 | * If this context is a clone of another, it might | |
1471 | * get swapped for another underneath us by | |
cdd6c482 | 1472 | * perf_event_task_sched_out, though the |
25346b93 PM |
1473 | * rcu_read_lock() protects us from any context |
1474 | * getting freed. Lock the context and check if it | |
1475 | * got swapped before we could get the lock, and retry | |
1476 | * if so. If we locked the right context, then it | |
1477 | * can't get swapped on us any more. | |
1478 | */ | |
2fd59077 | 1479 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1480 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1481 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1482 | rcu_read_unlock(); |
2fd59077 | 1483 | local_irq_restore(*flags); |
25346b93 PM |
1484 | goto retry; |
1485 | } | |
b49a9e7e | 1486 | |
63b6da39 | 1487 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1488 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1489 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1490 | ctx = NULL; |
828b6f0e PZ |
1491 | } else { |
1492 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1493 | } |
25346b93 PM |
1494 | } |
1495 | rcu_read_unlock(); | |
2fd59077 PM |
1496 | if (!ctx) |
1497 | local_irq_restore(*flags); | |
25346b93 PM |
1498 | return ctx; |
1499 | } | |
1500 | ||
1501 | /* | |
1502 | * Get the context for a task and increment its pin_count so it | |
1503 | * can't get swapped to another task. This also increments its | |
1504 | * reference count so that the context can't get freed. | |
1505 | */ | |
8dc85d54 PZ |
1506 | static struct perf_event_context * |
1507 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1508 | { |
cdd6c482 | 1509 | struct perf_event_context *ctx; |
25346b93 PM |
1510 | unsigned long flags; |
1511 | ||
8dc85d54 | 1512 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1513 | if (ctx) { |
1514 | ++ctx->pin_count; | |
e625cce1 | 1515 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1516 | } |
1517 | return ctx; | |
1518 | } | |
1519 | ||
cdd6c482 | 1520 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1521 | { |
1522 | unsigned long flags; | |
1523 | ||
e625cce1 | 1524 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1525 | --ctx->pin_count; |
e625cce1 | 1526 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1527 | } |
1528 | ||
f67218c3 PZ |
1529 | /* |
1530 | * Update the record of the current time in a context. | |
1531 | */ | |
1532 | static void update_context_time(struct perf_event_context *ctx) | |
1533 | { | |
1534 | u64 now = perf_clock(); | |
1535 | ||
1536 | ctx->time += now - ctx->timestamp; | |
1537 | ctx->timestamp = now; | |
1538 | } | |
1539 | ||
4158755d SE |
1540 | static u64 perf_event_time(struct perf_event *event) |
1541 | { | |
1542 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1543 | |
1544 | if (is_cgroup_event(event)) | |
1545 | return perf_cgroup_event_time(event); | |
1546 | ||
4158755d SE |
1547 | return ctx ? ctx->time : 0; |
1548 | } | |
1549 | ||
487f05e1 AS |
1550 | static enum event_type_t get_event_type(struct perf_event *event) |
1551 | { | |
1552 | struct perf_event_context *ctx = event->ctx; | |
1553 | enum event_type_t event_type; | |
1554 | ||
1555 | lockdep_assert_held(&ctx->lock); | |
1556 | ||
3bda69c1 AS |
1557 | /* |
1558 | * It's 'group type', really, because if our group leader is | |
1559 | * pinned, so are we. | |
1560 | */ | |
1561 | if (event->group_leader != event) | |
1562 | event = event->group_leader; | |
1563 | ||
487f05e1 AS |
1564 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1565 | if (!ctx->task) | |
1566 | event_type |= EVENT_CPU; | |
1567 | ||
1568 | return event_type; | |
1569 | } | |
1570 | ||
8e1a2031 | 1571 | /* |
161c85fa | 1572 | * Helper function to initialize event group nodes. |
8e1a2031 | 1573 | */ |
161c85fa | 1574 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1575 | { |
1576 | RB_CLEAR_NODE(&event->group_node); | |
1577 | event->group_index = 0; | |
1578 | } | |
1579 | ||
1580 | /* | |
1581 | * Extract pinned or flexible groups from the context | |
161c85fa | 1582 | * based on event attrs bits. |
8e1a2031 AB |
1583 | */ |
1584 | static struct perf_event_groups * | |
1585 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1586 | { |
1587 | if (event->attr.pinned) | |
1588 | return &ctx->pinned_groups; | |
1589 | else | |
1590 | return &ctx->flexible_groups; | |
1591 | } | |
1592 | ||
8e1a2031 | 1593 | /* |
161c85fa | 1594 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1595 | */ |
161c85fa | 1596 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1597 | { |
1598 | groups->tree = RB_ROOT; | |
1599 | groups->index = 0; | |
1600 | } | |
1601 | ||
a3b89864 PZ |
1602 | static inline struct cgroup *event_cgroup(const struct perf_event *event) |
1603 | { | |
1604 | struct cgroup *cgroup = NULL; | |
1605 | ||
1606 | #ifdef CONFIG_CGROUP_PERF | |
1607 | if (event->cgrp) | |
1608 | cgroup = event->cgrp->css.cgroup; | |
1609 | #endif | |
1610 | ||
1611 | return cgroup; | |
1612 | } | |
1613 | ||
8e1a2031 AB |
1614 | /* |
1615 | * Compare function for event groups; | |
161c85fa PZ |
1616 | * |
1617 | * Implements complex key that first sorts by CPU and then by virtual index | |
1618 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1619 | */ |
a3b89864 PZ |
1620 | static __always_inline int |
1621 | perf_event_groups_cmp(const int left_cpu, const struct cgroup *left_cgroup, | |
1622 | const u64 left_group_index, const struct perf_event *right) | |
8e1a2031 | 1623 | { |
a3b89864 PZ |
1624 | if (left_cpu < right->cpu) |
1625 | return -1; | |
1626 | if (left_cpu > right->cpu) | |
1627 | return 1; | |
161c85fa | 1628 | |
95ed6c70 | 1629 | #ifdef CONFIG_CGROUP_PERF |
a3b89864 PZ |
1630 | { |
1631 | const struct cgroup *right_cgroup = event_cgroup(right); | |
1632 | ||
1633 | if (left_cgroup != right_cgroup) { | |
1634 | if (!left_cgroup) { | |
1635 | /* | |
1636 | * Left has no cgroup but right does, no | |
1637 | * cgroups come first. | |
1638 | */ | |
1639 | return -1; | |
1640 | } | |
1641 | if (!right_cgroup) { | |
1642 | /* | |
1643 | * Right has no cgroup but left does, no | |
1644 | * cgroups come first. | |
1645 | */ | |
1646 | return 1; | |
1647 | } | |
1648 | /* Two dissimilar cgroups, order by id. */ | |
1649 | if (cgroup_id(left_cgroup) < cgroup_id(right_cgroup)) | |
1650 | return -1; | |
1651 | ||
1652 | return 1; | |
95ed6c70 | 1653 | } |
95ed6c70 IR |
1654 | } |
1655 | #endif | |
1656 | ||
a3b89864 PZ |
1657 | if (left_group_index < right->group_index) |
1658 | return -1; | |
1659 | if (left_group_index > right->group_index) | |
1660 | return 1; | |
1661 | ||
1662 | return 0; | |
1663 | } | |
161c85fa | 1664 | |
a3b89864 PZ |
1665 | #define __node_2_pe(node) \ |
1666 | rb_entry((node), struct perf_event, group_node) | |
1667 | ||
1668 | static inline bool __group_less(struct rb_node *a, const struct rb_node *b) | |
1669 | { | |
1670 | struct perf_event *e = __node_2_pe(a); | |
1671 | return perf_event_groups_cmp(e->cpu, event_cgroup(e), e->group_index, | |
1672 | __node_2_pe(b)) < 0; | |
1673 | } | |
1674 | ||
1675 | struct __group_key { | |
1676 | int cpu; | |
1677 | struct cgroup *cgroup; | |
1678 | }; | |
1679 | ||
1680 | static inline int __group_cmp(const void *key, const struct rb_node *node) | |
1681 | { | |
1682 | const struct __group_key *a = key; | |
1683 | const struct perf_event *b = __node_2_pe(node); | |
1684 | ||
1685 | /* partial/subtree match: @cpu, @cgroup; ignore: @group_index */ | |
1686 | return perf_event_groups_cmp(a->cpu, a->cgroup, b->group_index, b); | |
8e1a2031 AB |
1687 | } |
1688 | ||
1689 | /* | |
161c85fa PZ |
1690 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1691 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1692 | * subtree. | |
8e1a2031 AB |
1693 | */ |
1694 | static void | |
1695 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1696 | struct perf_event *event) |
8e1a2031 | 1697 | { |
8e1a2031 AB |
1698 | event->group_index = ++groups->index; |
1699 | ||
a3b89864 | 1700 | rb_add(&event->group_node, &groups->tree, __group_less); |
8e1a2031 AB |
1701 | } |
1702 | ||
1703 | /* | |
161c85fa | 1704 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1705 | */ |
1706 | static void | |
1707 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1708 | { | |
1709 | struct perf_event_groups *groups; | |
1710 | ||
1711 | groups = get_event_groups(event, ctx); | |
1712 | perf_event_groups_insert(groups, event); | |
1713 | } | |
1714 | ||
1715 | /* | |
161c85fa | 1716 | * Delete a group from a tree. |
8e1a2031 AB |
1717 | */ |
1718 | static void | |
1719 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1720 | struct perf_event *event) |
8e1a2031 | 1721 | { |
161c85fa PZ |
1722 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1723 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1724 | |
161c85fa | 1725 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1726 | init_event_group(event); |
1727 | } | |
1728 | ||
1729 | /* | |
161c85fa | 1730 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1731 | */ |
1732 | static void | |
1733 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1734 | { | |
1735 | struct perf_event_groups *groups; | |
1736 | ||
1737 | groups = get_event_groups(event, ctx); | |
1738 | perf_event_groups_delete(groups, event); | |
1739 | } | |
1740 | ||
1741 | /* | |
95ed6c70 | 1742 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1743 | */ |
1744 | static struct perf_event * | |
95ed6c70 IR |
1745 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1746 | struct cgroup *cgrp) | |
8e1a2031 | 1747 | { |
a3b89864 PZ |
1748 | struct __group_key key = { |
1749 | .cpu = cpu, | |
1750 | .cgroup = cgrp, | |
1751 | }; | |
1752 | struct rb_node *node; | |
95ed6c70 | 1753 | |
a3b89864 PZ |
1754 | node = rb_find_first(&key, &groups->tree, __group_cmp); |
1755 | if (node) | |
1756 | return __node_2_pe(node); | |
8e1a2031 | 1757 | |
a3b89864 | 1758 | return NULL; |
8e1a2031 AB |
1759 | } |
1760 | ||
1cac7b1a PZ |
1761 | /* |
1762 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1763 | */ | |
1764 | static struct perf_event * | |
1765 | perf_event_groups_next(struct perf_event *event) | |
1766 | { | |
a3b89864 PZ |
1767 | struct __group_key key = { |
1768 | .cpu = event->cpu, | |
1769 | .cgroup = event_cgroup(event), | |
1770 | }; | |
1771 | struct rb_node *next; | |
1cac7b1a | 1772 | |
a3b89864 PZ |
1773 | next = rb_next_match(&key, &event->group_node, __group_cmp); |
1774 | if (next) | |
1775 | return __node_2_pe(next); | |
95ed6c70 | 1776 | |
a3b89864 | 1777 | return NULL; |
1cac7b1a PZ |
1778 | } |
1779 | ||
8e1a2031 | 1780 | /* |
161c85fa | 1781 | * Iterate through the whole groups tree. |
8e1a2031 | 1782 | */ |
6e6804d2 PZ |
1783 | #define perf_event_groups_for_each(event, groups) \ |
1784 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1785 | typeof(*event), group_node); event; \ | |
1786 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1787 | typeof(*event), group_node)) | |
8e1a2031 | 1788 | |
fccc714b | 1789 | /* |
788faab7 | 1790 | * Add an event from the lists for its context. |
fccc714b PZ |
1791 | * Must be called with ctx->mutex and ctx->lock held. |
1792 | */ | |
04289bb9 | 1793 | static void |
cdd6c482 | 1794 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1795 | { |
c994d613 PZ |
1796 | lockdep_assert_held(&ctx->lock); |
1797 | ||
8a49542c PZ |
1798 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1799 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1800 | |
0d3d73aa PZ |
1801 | event->tstamp = perf_event_time(event); |
1802 | ||
04289bb9 | 1803 | /* |
8a49542c PZ |
1804 | * If we're a stand alone event or group leader, we go to the context |
1805 | * list, group events are kept attached to the group so that | |
1806 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1807 | */ |
8a49542c | 1808 | if (event->group_leader == event) { |
4ff6a8de | 1809 | event->group_caps = event->event_caps; |
8e1a2031 | 1810 | add_event_to_groups(event, ctx); |
5c148194 | 1811 | } |
592903cd | 1812 | |
cdd6c482 IM |
1813 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1814 | ctx->nr_events++; | |
1815 | if (event->attr.inherit_stat) | |
bfbd3381 | 1816 | ctx->nr_stat++; |
5a3126d4 | 1817 | |
33238c50 PZ |
1818 | if (event->state > PERF_EVENT_STATE_OFF) |
1819 | perf_cgroup_event_enable(event, ctx); | |
1820 | ||
5a3126d4 | 1821 | ctx->generation++; |
04289bb9 IM |
1822 | } |
1823 | ||
0231bb53 JO |
1824 | /* |
1825 | * Initialize event state based on the perf_event_attr::disabled. | |
1826 | */ | |
1827 | static inline void perf_event__state_init(struct perf_event *event) | |
1828 | { | |
1829 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1830 | PERF_EVENT_STATE_INACTIVE; | |
1831 | } | |
1832 | ||
a723968c | 1833 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1834 | { |
1835 | int entry = sizeof(u64); /* value */ | |
1836 | int size = 0; | |
1837 | int nr = 1; | |
1838 | ||
1839 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1840 | size += sizeof(u64); | |
1841 | ||
1842 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1843 | size += sizeof(u64); | |
1844 | ||
1845 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1846 | entry += sizeof(u64); | |
1847 | ||
1848 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1849 | nr += nr_siblings; |
c320c7b7 ACM |
1850 | size += sizeof(u64); |
1851 | } | |
1852 | ||
1853 | size += entry * nr; | |
1854 | event->read_size = size; | |
1855 | } | |
1856 | ||
a723968c | 1857 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1858 | { |
1859 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1860 | u16 size = 0; |
1861 | ||
c320c7b7 ACM |
1862 | if (sample_type & PERF_SAMPLE_IP) |
1863 | size += sizeof(data->ip); | |
1864 | ||
6844c09d ACM |
1865 | if (sample_type & PERF_SAMPLE_ADDR) |
1866 | size += sizeof(data->addr); | |
1867 | ||
1868 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1869 | size += sizeof(data->period); | |
1870 | ||
2a6c6b7d KL |
1871 | if (sample_type & PERF_SAMPLE_WEIGHT_TYPE) |
1872 | size += sizeof(data->weight.full); | |
c3feedf2 | 1873 | |
6844c09d ACM |
1874 | if (sample_type & PERF_SAMPLE_READ) |
1875 | size += event->read_size; | |
1876 | ||
d6be9ad6 SE |
1877 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1878 | size += sizeof(data->data_src.val); | |
1879 | ||
fdfbbd07 AK |
1880 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1881 | size += sizeof(data->txn); | |
1882 | ||
fc7ce9c7 KL |
1883 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1884 | size += sizeof(data->phys_addr); | |
1885 | ||
6546b19f NK |
1886 | if (sample_type & PERF_SAMPLE_CGROUP) |
1887 | size += sizeof(data->cgroup); | |
1888 | ||
8d97e718 KL |
1889 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
1890 | size += sizeof(data->data_page_size); | |
1891 | ||
995f088e SE |
1892 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
1893 | size += sizeof(data->code_page_size); | |
1894 | ||
6844c09d ACM |
1895 | event->header_size = size; |
1896 | } | |
1897 | ||
a723968c PZ |
1898 | /* |
1899 | * Called at perf_event creation and when events are attached/detached from a | |
1900 | * group. | |
1901 | */ | |
1902 | static void perf_event__header_size(struct perf_event *event) | |
1903 | { | |
1904 | __perf_event_read_size(event, | |
1905 | event->group_leader->nr_siblings); | |
1906 | __perf_event_header_size(event, event->attr.sample_type); | |
1907 | } | |
1908 | ||
6844c09d ACM |
1909 | static void perf_event__id_header_size(struct perf_event *event) |
1910 | { | |
1911 | struct perf_sample_data *data; | |
1912 | u64 sample_type = event->attr.sample_type; | |
1913 | u16 size = 0; | |
1914 | ||
c320c7b7 ACM |
1915 | if (sample_type & PERF_SAMPLE_TID) |
1916 | size += sizeof(data->tid_entry); | |
1917 | ||
1918 | if (sample_type & PERF_SAMPLE_TIME) | |
1919 | size += sizeof(data->time); | |
1920 | ||
ff3d527c AH |
1921 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1922 | size += sizeof(data->id); | |
1923 | ||
c320c7b7 ACM |
1924 | if (sample_type & PERF_SAMPLE_ID) |
1925 | size += sizeof(data->id); | |
1926 | ||
1927 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1928 | size += sizeof(data->stream_id); | |
1929 | ||
1930 | if (sample_type & PERF_SAMPLE_CPU) | |
1931 | size += sizeof(data->cpu_entry); | |
1932 | ||
6844c09d | 1933 | event->id_header_size = size; |
c320c7b7 ACM |
1934 | } |
1935 | ||
a723968c PZ |
1936 | static bool perf_event_validate_size(struct perf_event *event) |
1937 | { | |
1938 | /* | |
1939 | * The values computed here will be over-written when we actually | |
1940 | * attach the event. | |
1941 | */ | |
1942 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1943 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1944 | perf_event__id_header_size(event); | |
1945 | ||
1946 | /* | |
1947 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1948 | * Conservative limit to allow for callchains and other variable fields. | |
1949 | */ | |
1950 | if (event->read_size + event->header_size + | |
1951 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1952 | return false; | |
1953 | ||
1954 | return true; | |
1955 | } | |
1956 | ||
8a49542c PZ |
1957 | static void perf_group_attach(struct perf_event *event) |
1958 | { | |
c320c7b7 | 1959 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1960 | |
a76a82a3 PZ |
1961 | lockdep_assert_held(&event->ctx->lock); |
1962 | ||
74c3337c PZ |
1963 | /* |
1964 | * We can have double attach due to group movement in perf_event_open. | |
1965 | */ | |
1966 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1967 | return; | |
1968 | ||
8a49542c PZ |
1969 | event->attach_state |= PERF_ATTACH_GROUP; |
1970 | ||
1971 | if (group_leader == event) | |
1972 | return; | |
1973 | ||
652884fe PZ |
1974 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1975 | ||
4ff6a8de | 1976 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1977 | |
8343aae6 | 1978 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1979 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1980 | |
1981 | perf_event__header_size(group_leader); | |
1982 | ||
edb39592 | 1983 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1984 | perf_event__header_size(pos); |
8a49542c PZ |
1985 | } |
1986 | ||
a63eaf34 | 1987 | /* |
788faab7 | 1988 | * Remove an event from the lists for its context. |
fccc714b | 1989 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1990 | */ |
04289bb9 | 1991 | static void |
cdd6c482 | 1992 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1993 | { |
652884fe PZ |
1994 | WARN_ON_ONCE(event->ctx != ctx); |
1995 | lockdep_assert_held(&ctx->lock); | |
1996 | ||
8a49542c PZ |
1997 | /* |
1998 | * We can have double detach due to exit/hot-unplug + close. | |
1999 | */ | |
2000 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 2001 | return; |
8a49542c PZ |
2002 | |
2003 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
2004 | ||
cdd6c482 IM |
2005 | ctx->nr_events--; |
2006 | if (event->attr.inherit_stat) | |
bfbd3381 | 2007 | ctx->nr_stat--; |
8bc20959 | 2008 | |
cdd6c482 | 2009 | list_del_rcu(&event->event_entry); |
04289bb9 | 2010 | |
8a49542c | 2011 | if (event->group_leader == event) |
8e1a2031 | 2012 | del_event_from_groups(event, ctx); |
5c148194 | 2013 | |
b2e74a26 SE |
2014 | /* |
2015 | * If event was in error state, then keep it | |
2016 | * that way, otherwise bogus counts will be | |
2017 | * returned on read(). The only way to get out | |
2018 | * of error state is by explicit re-enabling | |
2019 | * of the event | |
2020 | */ | |
33238c50 PZ |
2021 | if (event->state > PERF_EVENT_STATE_OFF) { |
2022 | perf_cgroup_event_disable(event, ctx); | |
0d3d73aa | 2023 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
33238c50 | 2024 | } |
5a3126d4 PZ |
2025 | |
2026 | ctx->generation++; | |
050735b0 PZ |
2027 | } |
2028 | ||
ab43762e AS |
2029 | static int |
2030 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2031 | { | |
2032 | if (!has_aux(aux_event)) | |
2033 | return 0; | |
2034 | ||
2035 | if (!event->pmu->aux_output_match) | |
2036 | return 0; | |
2037 | ||
2038 | return event->pmu->aux_output_match(aux_event); | |
2039 | } | |
2040 | ||
2041 | static void put_event(struct perf_event *event); | |
2042 | static void event_sched_out(struct perf_event *event, | |
2043 | struct perf_cpu_context *cpuctx, | |
2044 | struct perf_event_context *ctx); | |
2045 | ||
2046 | static void perf_put_aux_event(struct perf_event *event) | |
2047 | { | |
2048 | struct perf_event_context *ctx = event->ctx; | |
2049 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2050 | struct perf_event *iter; | |
2051 | ||
2052 | /* | |
2053 | * If event uses aux_event tear down the link | |
2054 | */ | |
2055 | if (event->aux_event) { | |
2056 | iter = event->aux_event; | |
2057 | event->aux_event = NULL; | |
2058 | put_event(iter); | |
2059 | return; | |
2060 | } | |
2061 | ||
2062 | /* | |
2063 | * If the event is an aux_event, tear down all links to | |
2064 | * it from other events. | |
2065 | */ | |
2066 | for_each_sibling_event(iter, event->group_leader) { | |
2067 | if (iter->aux_event != event) | |
2068 | continue; | |
2069 | ||
2070 | iter->aux_event = NULL; | |
2071 | put_event(event); | |
2072 | ||
2073 | /* | |
2074 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2075 | * state so that we don't try to schedule it again. Note | |
2076 | * that perf_event_enable() will clear the ERROR status. | |
2077 | */ | |
2078 | event_sched_out(iter, cpuctx, ctx); | |
2079 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2080 | } | |
2081 | } | |
2082 | ||
a4faf00d AS |
2083 | static bool perf_need_aux_event(struct perf_event *event) |
2084 | { | |
2085 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2086 | } | |
2087 | ||
ab43762e AS |
2088 | static int perf_get_aux_event(struct perf_event *event, |
2089 | struct perf_event *group_leader) | |
2090 | { | |
2091 | /* | |
2092 | * Our group leader must be an aux event if we want to be | |
2093 | * an aux_output. This way, the aux event will precede its | |
2094 | * aux_output events in the group, and therefore will always | |
2095 | * schedule first. | |
2096 | */ | |
2097 | if (!group_leader) | |
2098 | return 0; | |
2099 | ||
a4faf00d AS |
2100 | /* |
2101 | * aux_output and aux_sample_size are mutually exclusive. | |
2102 | */ | |
2103 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2104 | return 0; | |
2105 | ||
2106 | if (event->attr.aux_output && | |
2107 | !perf_aux_output_match(event, group_leader)) | |
2108 | return 0; | |
2109 | ||
2110 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2111 | return 0; |
2112 | ||
2113 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2114 | return 0; | |
2115 | ||
2116 | /* | |
2117 | * Link aux_outputs to their aux event; this is undone in | |
2118 | * perf_group_detach() by perf_put_aux_event(). When the | |
2119 | * group in torn down, the aux_output events loose their | |
2120 | * link to the aux_event and can't schedule any more. | |
2121 | */ | |
2122 | event->aux_event = group_leader; | |
2123 | ||
2124 | return 1; | |
2125 | } | |
2126 | ||
ab6f824c PZ |
2127 | static inline struct list_head *get_event_list(struct perf_event *event) |
2128 | { | |
2129 | struct perf_event_context *ctx = event->ctx; | |
2130 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2131 | } | |
2132 | ||
9f0c4fa1 KL |
2133 | /* |
2134 | * Events that have PERF_EV_CAP_SIBLING require being part of a group and | |
2135 | * cannot exist on their own, schedule them out and move them into the ERROR | |
2136 | * state. Also see _perf_event_enable(), it will not be able to recover | |
2137 | * this ERROR state. | |
2138 | */ | |
2139 | static inline void perf_remove_sibling_event(struct perf_event *event) | |
2140 | { | |
2141 | struct perf_event_context *ctx = event->ctx; | |
2142 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2143 | ||
2144 | event_sched_out(event, cpuctx, ctx); | |
2145 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2146 | } | |
2147 | ||
8a49542c | 2148 | static void perf_group_detach(struct perf_event *event) |
050735b0 | 2149 | { |
9f0c4fa1 | 2150 | struct perf_event *leader = event->group_leader; |
050735b0 | 2151 | struct perf_event *sibling, *tmp; |
6668128a | 2152 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2153 | |
6668128a | 2154 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2155 | |
8a49542c PZ |
2156 | /* |
2157 | * We can have double detach due to exit/hot-unplug + close. | |
2158 | */ | |
2159 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2160 | return; | |
2161 | ||
2162 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2163 | ||
ab43762e AS |
2164 | perf_put_aux_event(event); |
2165 | ||
8a49542c PZ |
2166 | /* |
2167 | * If this is a sibling, remove it from its group. | |
2168 | */ | |
9f0c4fa1 | 2169 | if (leader != event) { |
8343aae6 | 2170 | list_del_init(&event->sibling_list); |
8a49542c | 2171 | event->group_leader->nr_siblings--; |
c320c7b7 | 2172 | goto out; |
8a49542c PZ |
2173 | } |
2174 | ||
04289bb9 | 2175 | /* |
cdd6c482 IM |
2176 | * If this was a group event with sibling events then |
2177 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2178 | * to whatever list we are on. |
04289bb9 | 2179 | */ |
8343aae6 | 2180 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2181 | |
9f0c4fa1 KL |
2182 | if (sibling->event_caps & PERF_EV_CAP_SIBLING) |
2183 | perf_remove_sibling_event(sibling); | |
2184 | ||
04289bb9 | 2185 | sibling->group_leader = sibling; |
24868367 | 2186 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2187 | |
2188 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2189 | sibling->group_caps = event->group_caps; |
652884fe | 2190 | |
8e1a2031 | 2191 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2192 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2193 | |
ab6f824c PZ |
2194 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2195 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2196 | } |
2197 | ||
652884fe | 2198 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2199 | } |
c320c7b7 ACM |
2200 | |
2201 | out: | |
9f0c4fa1 | 2202 | for_each_sibling_event(tmp, leader) |
c320c7b7 | 2203 | perf_event__header_size(tmp); |
9f0c4fa1 KL |
2204 | |
2205 | perf_event__header_size(leader); | |
04289bb9 IM |
2206 | } |
2207 | ||
ef54c1a4 PZ |
2208 | static void sync_child_event(struct perf_event *child_event); |
2209 | ||
2210 | static void perf_child_detach(struct perf_event *event) | |
2211 | { | |
2212 | struct perf_event *parent_event = event->parent; | |
2213 | ||
2214 | if (!(event->attach_state & PERF_ATTACH_CHILD)) | |
2215 | return; | |
2216 | ||
2217 | event->attach_state &= ~PERF_ATTACH_CHILD; | |
2218 | ||
2219 | if (WARN_ON_ONCE(!parent_event)) | |
2220 | return; | |
2221 | ||
2222 | lockdep_assert_held(&parent_event->child_mutex); | |
2223 | ||
2224 | sync_child_event(event); | |
2225 | list_del_init(&event->child_list); | |
2226 | } | |
2227 | ||
fadfe7be JO |
2228 | static bool is_orphaned_event(struct perf_event *event) |
2229 | { | |
a69b0ca4 | 2230 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2231 | } |
2232 | ||
2c81a647 | 2233 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2234 | { |
2235 | struct pmu *pmu = event->pmu; | |
2236 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2237 | } | |
2238 | ||
2c81a647 MR |
2239 | /* |
2240 | * Check whether we should attempt to schedule an event group based on | |
2241 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2242 | * potentially with a SW leader, so we must check all the filters, to | |
2243 | * determine whether a group is schedulable: | |
2244 | */ | |
2245 | static inline int pmu_filter_match(struct perf_event *event) | |
2246 | { | |
edb39592 | 2247 | struct perf_event *sibling; |
2c81a647 MR |
2248 | |
2249 | if (!__pmu_filter_match(event)) | |
2250 | return 0; | |
2251 | ||
edb39592 PZ |
2252 | for_each_sibling_event(sibling, event) { |
2253 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2254 | return 0; |
2255 | } | |
2256 | ||
2257 | return 1; | |
2258 | } | |
2259 | ||
fa66f07a SE |
2260 | static inline int |
2261 | event_filter_match(struct perf_event *event) | |
2262 | { | |
0b8f1e2e PZ |
2263 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2264 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2265 | } |
2266 | ||
9ffcfa6f SE |
2267 | static void |
2268 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2269 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2270 | struct perf_event_context *ctx) |
3b6f9e5c | 2271 | { |
0d3d73aa | 2272 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2273 | |
2274 | WARN_ON_ONCE(event->ctx != ctx); | |
2275 | lockdep_assert_held(&ctx->lock); | |
2276 | ||
cdd6c482 | 2277 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2278 | return; |
3b6f9e5c | 2279 | |
6668128a PZ |
2280 | /* |
2281 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2282 | * we can schedule events _OUT_ individually through things like | |
2283 | * __perf_remove_from_context(). | |
2284 | */ | |
2285 | list_del_init(&event->active_list); | |
2286 | ||
44377277 AS |
2287 | perf_pmu_disable(event->pmu); |
2288 | ||
28a967c3 PZ |
2289 | event->pmu->del(event, 0); |
2290 | event->oncpu = -1; | |
0d3d73aa | 2291 | |
1d54ad94 PZ |
2292 | if (READ_ONCE(event->pending_disable) >= 0) { |
2293 | WRITE_ONCE(event->pending_disable, -1); | |
33238c50 | 2294 | perf_cgroup_event_disable(event, ctx); |
0d3d73aa | 2295 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2296 | } |
0d3d73aa | 2297 | perf_event_set_state(event, state); |
3b6f9e5c | 2298 | |
cdd6c482 | 2299 | if (!is_software_event(event)) |
3b6f9e5c | 2300 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2301 | if (!--ctx->nr_active) |
2302 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2303 | if (event->attr.freq && event->attr.sample_freq) |
2304 | ctx->nr_freq--; | |
cdd6c482 | 2305 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2306 | cpuctx->exclusive = 0; |
44377277 AS |
2307 | |
2308 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2309 | } |
2310 | ||
d859e29f | 2311 | static void |
cdd6c482 | 2312 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2313 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2314 | struct perf_event_context *ctx) |
d859e29f | 2315 | { |
cdd6c482 | 2316 | struct perf_event *event; |
0d3d73aa PZ |
2317 | |
2318 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2319 | return; | |
d859e29f | 2320 | |
3f005e7d MR |
2321 | perf_pmu_disable(ctx->pmu); |
2322 | ||
cdd6c482 | 2323 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2324 | |
2325 | /* | |
2326 | * Schedule out siblings (if any): | |
2327 | */ | |
edb39592 | 2328 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2329 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2330 | |
3f005e7d | 2331 | perf_pmu_enable(ctx->pmu); |
d859e29f PM |
2332 | } |
2333 | ||
45a0e07a | 2334 | #define DETACH_GROUP 0x01UL |
ef54c1a4 | 2335 | #define DETACH_CHILD 0x02UL |
0017960f | 2336 | |
0793a61d | 2337 | /* |
cdd6c482 | 2338 | * Cross CPU call to remove a performance event |
0793a61d | 2339 | * |
cdd6c482 | 2340 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2341 | * remove it from the context list. |
2342 | */ | |
fae3fde6 PZ |
2343 | static void |
2344 | __perf_remove_from_context(struct perf_event *event, | |
2345 | struct perf_cpu_context *cpuctx, | |
2346 | struct perf_event_context *ctx, | |
2347 | void *info) | |
0793a61d | 2348 | { |
45a0e07a | 2349 | unsigned long flags = (unsigned long)info; |
0793a61d | 2350 | |
3c5c8711 PZ |
2351 | if (ctx->is_active & EVENT_TIME) { |
2352 | update_context_time(ctx); | |
2353 | update_cgrp_time_from_cpuctx(cpuctx); | |
2354 | } | |
2355 | ||
cdd6c482 | 2356 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2357 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2358 | perf_group_detach(event); |
ef54c1a4 PZ |
2359 | if (flags & DETACH_CHILD) |
2360 | perf_child_detach(event); | |
cdd6c482 | 2361 | list_del_event(event, ctx); |
39a43640 PZ |
2362 | |
2363 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2364 | ctx->is_active = 0; |
90c91dfb | 2365 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2366 | if (ctx->task) { |
2367 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2368 | cpuctx->task_ctx = NULL; | |
2369 | } | |
64ce3126 | 2370 | } |
0793a61d TG |
2371 | } |
2372 | ||
0793a61d | 2373 | /* |
cdd6c482 | 2374 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2375 | * |
cdd6c482 IM |
2376 | * If event->ctx is a cloned context, callers must make sure that |
2377 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2378 | * remains valid. This is OK when called from perf_release since |
2379 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2380 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2381 | * context has been detached from its task. |
0793a61d | 2382 | */ |
45a0e07a | 2383 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2384 | { |
a76a82a3 PZ |
2385 | struct perf_event_context *ctx = event->ctx; |
2386 | ||
2387 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2388 | |
a76a82a3 | 2389 | /* |
ef54c1a4 PZ |
2390 | * Because of perf_event_exit_task(), perf_remove_from_context() ought |
2391 | * to work in the face of TASK_TOMBSTONE, unlike every other | |
2392 | * event_function_call() user. | |
a76a82a3 | 2393 | */ |
ef54c1a4 PZ |
2394 | raw_spin_lock_irq(&ctx->lock); |
2395 | if (!ctx->is_active) { | |
2396 | __perf_remove_from_context(event, __get_cpu_context(ctx), | |
2397 | ctx, (void *)flags); | |
a76a82a3 | 2398 | raw_spin_unlock_irq(&ctx->lock); |
ef54c1a4 | 2399 | return; |
a76a82a3 | 2400 | } |
ef54c1a4 PZ |
2401 | raw_spin_unlock_irq(&ctx->lock); |
2402 | ||
2403 | event_function_call(event, __perf_remove_from_context, (void *)flags); | |
0793a61d TG |
2404 | } |
2405 | ||
d859e29f | 2406 | /* |
cdd6c482 | 2407 | * Cross CPU call to disable a performance event |
d859e29f | 2408 | */ |
fae3fde6 PZ |
2409 | static void __perf_event_disable(struct perf_event *event, |
2410 | struct perf_cpu_context *cpuctx, | |
2411 | struct perf_event_context *ctx, | |
2412 | void *info) | |
7b648018 | 2413 | { |
fae3fde6 PZ |
2414 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2415 | return; | |
7b648018 | 2416 | |
3c5c8711 PZ |
2417 | if (ctx->is_active & EVENT_TIME) { |
2418 | update_context_time(ctx); | |
2419 | update_cgrp_time_from_event(event); | |
2420 | } | |
2421 | ||
fae3fde6 PZ |
2422 | if (event == event->group_leader) |
2423 | group_sched_out(event, cpuctx, ctx); | |
2424 | else | |
2425 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2426 | |
2427 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
33238c50 | 2428 | perf_cgroup_event_disable(event, ctx); |
7b648018 PZ |
2429 | } |
2430 | ||
d859e29f | 2431 | /* |
788faab7 | 2432 | * Disable an event. |
c93f7669 | 2433 | * |
cdd6c482 IM |
2434 | * If event->ctx is a cloned context, callers must make sure that |
2435 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2436 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2437 | * perf_event_for_each_child or perf_event_for_each because they |
2438 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2439 | * goes to exit will block in perf_event_exit_event(). |
2440 | * | |
cdd6c482 | 2441 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2442 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2443 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2444 | */ |
f63a8daa | 2445 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2446 | { |
cdd6c482 | 2447 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2448 | |
e625cce1 | 2449 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2450 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2451 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2452 | return; |
53cfbf59 | 2453 | } |
e625cce1 | 2454 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2455 | |
fae3fde6 PZ |
2456 | event_function_call(event, __perf_event_disable, NULL); |
2457 | } | |
2458 | ||
2459 | void perf_event_disable_local(struct perf_event *event) | |
2460 | { | |
2461 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2462 | } |
f63a8daa PZ |
2463 | |
2464 | /* | |
2465 | * Strictly speaking kernel users cannot create groups and therefore this | |
2466 | * interface does not need the perf_event_ctx_lock() magic. | |
2467 | */ | |
2468 | void perf_event_disable(struct perf_event *event) | |
2469 | { | |
2470 | struct perf_event_context *ctx; | |
2471 | ||
2472 | ctx = perf_event_ctx_lock(event); | |
2473 | _perf_event_disable(event); | |
2474 | perf_event_ctx_unlock(event, ctx); | |
2475 | } | |
dcfce4a0 | 2476 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2477 | |
5aab90ce JO |
2478 | void perf_event_disable_inatomic(struct perf_event *event) |
2479 | { | |
1d54ad94 PZ |
2480 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2481 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2482 | irq_work_queue(&event->pending); |
2483 | } | |
2484 | ||
e5d1367f | 2485 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2486 | struct perf_event_context *ctx) |
e5d1367f SE |
2487 | { |
2488 | /* | |
2489 | * use the correct time source for the time snapshot | |
2490 | * | |
2491 | * We could get by without this by leveraging the | |
2492 | * fact that to get to this function, the caller | |
2493 | * has most likely already called update_context_time() | |
2494 | * and update_cgrp_time_xx() and thus both timestamp | |
2495 | * are identical (or very close). Given that tstamp is, | |
2496 | * already adjusted for cgroup, we could say that: | |
2497 | * tstamp - ctx->timestamp | |
2498 | * is equivalent to | |
2499 | * tstamp - cgrp->timestamp. | |
2500 | * | |
2501 | * Then, in perf_output_read(), the calculation would | |
2502 | * work with no changes because: | |
2503 | * - event is guaranteed scheduled in | |
2504 | * - no scheduled out in between | |
2505 | * - thus the timestamp would be the same | |
2506 | * | |
2507 | * But this is a bit hairy. | |
2508 | * | |
2509 | * So instead, we have an explicit cgroup call to remain | |
c034f48e | 2510 | * within the time source all along. We believe it |
e5d1367f SE |
2511 | * is cleaner and simpler to understand. |
2512 | */ | |
2513 | if (is_cgroup_event(event)) | |
0d3d73aa | 2514 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2515 | else |
0d3d73aa | 2516 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2517 | } |
2518 | ||
4fe757dd PZ |
2519 | #define MAX_INTERRUPTS (~0ULL) |
2520 | ||
2521 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2522 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2523 | |
235c7fc7 | 2524 | static int |
9ffcfa6f | 2525 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2526 | struct perf_cpu_context *cpuctx, |
6e37738a | 2527 | struct perf_event_context *ctx) |
235c7fc7 | 2528 | { |
44377277 | 2529 | int ret = 0; |
4158755d | 2530 | |
ab6f824c PZ |
2531 | WARN_ON_ONCE(event->ctx != ctx); |
2532 | ||
63342411 PZ |
2533 | lockdep_assert_held(&ctx->lock); |
2534 | ||
cdd6c482 | 2535 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2536 | return 0; |
2537 | ||
95ff4ca2 AS |
2538 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2539 | /* | |
0c1cbc18 PZ |
2540 | * Order event::oncpu write to happen before the ACTIVE state is |
2541 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2542 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2543 | */ |
2544 | smp_wmb(); | |
0d3d73aa | 2545 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2546 | |
2547 | /* | |
2548 | * Unthrottle events, since we scheduled we might have missed several | |
2549 | * ticks already, also for a heavily scheduling task there is little | |
2550 | * guarantee it'll get a tick in a timely manner. | |
2551 | */ | |
2552 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2553 | perf_log_throttle(event, 1); | |
2554 | event->hw.interrupts = 0; | |
2555 | } | |
2556 | ||
44377277 AS |
2557 | perf_pmu_disable(event->pmu); |
2558 | ||
0d3d73aa | 2559 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2560 | |
ec0d7729 AS |
2561 | perf_log_itrace_start(event); |
2562 | ||
a4eaf7f1 | 2563 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2564 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2565 | event->oncpu = -1; |
44377277 AS |
2566 | ret = -EAGAIN; |
2567 | goto out; | |
235c7fc7 IM |
2568 | } |
2569 | ||
cdd6c482 | 2570 | if (!is_software_event(event)) |
3b6f9e5c | 2571 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2572 | if (!ctx->nr_active++) |
2573 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2574 | if (event->attr.freq && event->attr.sample_freq) |
2575 | ctx->nr_freq++; | |
235c7fc7 | 2576 | |
cdd6c482 | 2577 | if (event->attr.exclusive) |
3b6f9e5c PM |
2578 | cpuctx->exclusive = 1; |
2579 | ||
44377277 AS |
2580 | out: |
2581 | perf_pmu_enable(event->pmu); | |
2582 | ||
2583 | return ret; | |
235c7fc7 IM |
2584 | } |
2585 | ||
6751b71e | 2586 | static int |
cdd6c482 | 2587 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2588 | struct perf_cpu_context *cpuctx, |
6e37738a | 2589 | struct perf_event_context *ctx) |
6751b71e | 2590 | { |
6bde9b6c | 2591 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2592 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2593 | |
cdd6c482 | 2594 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2595 | return 0; |
2596 | ||
fbbe0701 | 2597 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2598 | |
251ff2d4 PZ |
2599 | if (event_sched_in(group_event, cpuctx, ctx)) |
2600 | goto error; | |
6751b71e PM |
2601 | |
2602 | /* | |
2603 | * Schedule in siblings as one group (if any): | |
2604 | */ | |
edb39592 | 2605 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2606 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2607 | partial_group = event; |
6751b71e PM |
2608 | goto group_error; |
2609 | } | |
2610 | } | |
2611 | ||
9ffcfa6f | 2612 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2613 | return 0; |
9ffcfa6f | 2614 | |
6751b71e PM |
2615 | group_error: |
2616 | /* | |
2617 | * Groups can be scheduled in as one unit only, so undo any | |
2618 | * partial group before returning: | |
0d3d73aa | 2619 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2620 | */ |
edb39592 | 2621 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2622 | if (event == partial_group) |
0d3d73aa | 2623 | break; |
d7842da4 | 2624 | |
0d3d73aa | 2625 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2626 | } |
9ffcfa6f | 2627 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2628 | |
251ff2d4 | 2629 | error: |
ad5133b7 | 2630 | pmu->cancel_txn(pmu); |
6751b71e PM |
2631 | return -EAGAIN; |
2632 | } | |
2633 | ||
3b6f9e5c | 2634 | /* |
cdd6c482 | 2635 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2636 | */ |
cdd6c482 | 2637 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2638 | struct perf_cpu_context *cpuctx, |
2639 | int can_add_hw) | |
2640 | { | |
2641 | /* | |
cdd6c482 | 2642 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2643 | */ |
4ff6a8de | 2644 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2645 | return 1; |
2646 | /* | |
2647 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2648 | * events can go on. |
3b6f9e5c PM |
2649 | */ |
2650 | if (cpuctx->exclusive) | |
2651 | return 0; | |
2652 | /* | |
2653 | * If this group is exclusive and there are already | |
cdd6c482 | 2654 | * events on the CPU, it can't go on. |
3b6f9e5c | 2655 | */ |
1908dc91 | 2656 | if (event->attr.exclusive && !list_empty(get_event_list(event))) |
3b6f9e5c PM |
2657 | return 0; |
2658 | /* | |
2659 | * Otherwise, try to add it if all previous groups were able | |
2660 | * to go on. | |
2661 | */ | |
2662 | return can_add_hw; | |
2663 | } | |
2664 | ||
cdd6c482 IM |
2665 | static void add_event_to_ctx(struct perf_event *event, |
2666 | struct perf_event_context *ctx) | |
53cfbf59 | 2667 | { |
cdd6c482 | 2668 | list_add_event(event, ctx); |
8a49542c | 2669 | perf_group_attach(event); |
53cfbf59 PM |
2670 | } |
2671 | ||
bd2afa49 PZ |
2672 | static void ctx_sched_out(struct perf_event_context *ctx, |
2673 | struct perf_cpu_context *cpuctx, | |
2674 | enum event_type_t event_type); | |
2c29ef0f PZ |
2675 | static void |
2676 | ctx_sched_in(struct perf_event_context *ctx, | |
2677 | struct perf_cpu_context *cpuctx, | |
2678 | enum event_type_t event_type, | |
2679 | struct task_struct *task); | |
fe4b04fa | 2680 | |
bd2afa49 | 2681 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2682 | struct perf_event_context *ctx, |
2683 | enum event_type_t event_type) | |
bd2afa49 PZ |
2684 | { |
2685 | if (!cpuctx->task_ctx) | |
2686 | return; | |
2687 | ||
2688 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2689 | return; | |
2690 | ||
487f05e1 | 2691 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2692 | } |
2693 | ||
dce5855b PZ |
2694 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2695 | struct perf_event_context *ctx, | |
2696 | struct task_struct *task) | |
2697 | { | |
2698 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2699 | if (ctx) | |
2700 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2701 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2702 | if (ctx) | |
2703 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2704 | } | |
2705 | ||
487f05e1 AS |
2706 | /* |
2707 | * We want to maintain the following priority of scheduling: | |
2708 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2709 | * - task pinned (EVENT_PINNED) | |
2710 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2711 | * - task flexible (EVENT_FLEXIBLE). | |
2712 | * | |
2713 | * In order to avoid unscheduling and scheduling back in everything every | |
2714 | * time an event is added, only do it for the groups of equal priority and | |
2715 | * below. | |
2716 | * | |
2717 | * This can be called after a batch operation on task events, in which case | |
2718 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2719 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2720 | */ | |
3e349507 | 2721 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2722 | struct perf_event_context *task_ctx, |
2723 | enum event_type_t event_type) | |
0017960f | 2724 | { |
bd903afe | 2725 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2726 | bool cpu_event = !!(event_type & EVENT_CPU); |
2727 | ||
2728 | /* | |
2729 | * If pinned groups are involved, flexible groups also need to be | |
2730 | * scheduled out. | |
2731 | */ | |
2732 | if (event_type & EVENT_PINNED) | |
2733 | event_type |= EVENT_FLEXIBLE; | |
2734 | ||
bd903afe SL |
2735 | ctx_event_type = event_type & EVENT_ALL; |
2736 | ||
3e349507 PZ |
2737 | perf_pmu_disable(cpuctx->ctx.pmu); |
2738 | if (task_ctx) | |
487f05e1 AS |
2739 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2740 | ||
2741 | /* | |
2742 | * Decide which cpu ctx groups to schedule out based on the types | |
2743 | * of events that caused rescheduling: | |
2744 | * - EVENT_CPU: schedule out corresponding groups; | |
2745 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2746 | * - otherwise, do nothing more. | |
2747 | */ | |
2748 | if (cpu_event) | |
2749 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2750 | else if (ctx_event_type & EVENT_PINNED) | |
2751 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2752 | ||
3e349507 PZ |
2753 | perf_event_sched_in(cpuctx, task_ctx, current); |
2754 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2755 | } |
2756 | ||
c68d224e SE |
2757 | void perf_pmu_resched(struct pmu *pmu) |
2758 | { | |
2759 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2760 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2761 | ||
2762 | perf_ctx_lock(cpuctx, task_ctx); | |
2763 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2764 | perf_ctx_unlock(cpuctx, task_ctx); | |
2765 | } | |
2766 | ||
0793a61d | 2767 | /* |
cdd6c482 | 2768 | * Cross CPU call to install and enable a performance event |
682076ae | 2769 | * |
a096309b PZ |
2770 | * Very similar to remote_function() + event_function() but cannot assume that |
2771 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2772 | */ |
fe4b04fa | 2773 | static int __perf_install_in_context(void *info) |
0793a61d | 2774 | { |
a096309b PZ |
2775 | struct perf_event *event = info; |
2776 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2777 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2778 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2779 | bool reprogram = true; |
a096309b | 2780 | int ret = 0; |
0793a61d | 2781 | |
63b6da39 | 2782 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2783 | if (ctx->task) { |
b58f6b0d PZ |
2784 | raw_spin_lock(&ctx->lock); |
2785 | task_ctx = ctx; | |
a096309b | 2786 | |
63cae12b | 2787 | reprogram = (ctx->task == current); |
b58f6b0d | 2788 | |
39a43640 | 2789 | /* |
63cae12b PZ |
2790 | * If the task is running, it must be running on this CPU, |
2791 | * otherwise we cannot reprogram things. | |
2792 | * | |
2793 | * If its not running, we don't care, ctx->lock will | |
2794 | * serialize against it becoming runnable. | |
39a43640 | 2795 | */ |
63cae12b PZ |
2796 | if (task_curr(ctx->task) && !reprogram) { |
2797 | ret = -ESRCH; | |
2798 | goto unlock; | |
2799 | } | |
a096309b | 2800 | |
63cae12b | 2801 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2802 | } else if (task_ctx) { |
2803 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2804 | } |
b58f6b0d | 2805 | |
33801b94 | 2806 | #ifdef CONFIG_CGROUP_PERF |
33238c50 | 2807 | if (event->state > PERF_EVENT_STATE_OFF && is_cgroup_event(event)) { |
33801b94 | 2808 | /* |
2809 | * If the current cgroup doesn't match the event's | |
2810 | * cgroup, we should not try to schedule it. | |
2811 | */ | |
2812 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2813 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2814 | event->cgrp->css.cgroup); | |
2815 | } | |
2816 | #endif | |
2817 | ||
63cae12b | 2818 | if (reprogram) { |
a096309b PZ |
2819 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2820 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2821 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2822 | } else { |
2823 | add_event_to_ctx(event, ctx); | |
2824 | } | |
2825 | ||
63b6da39 | 2826 | unlock: |
2c29ef0f | 2827 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2828 | |
a096309b | 2829 | return ret; |
0793a61d TG |
2830 | } |
2831 | ||
8a58ddae AS |
2832 | static bool exclusive_event_installable(struct perf_event *event, |
2833 | struct perf_event_context *ctx); | |
2834 | ||
0793a61d | 2835 | /* |
a096309b PZ |
2836 | * Attach a performance event to a context. |
2837 | * | |
2838 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2839 | */ |
2840 | static void | |
cdd6c482 IM |
2841 | perf_install_in_context(struct perf_event_context *ctx, |
2842 | struct perf_event *event, | |
0793a61d TG |
2843 | int cpu) |
2844 | { | |
a096309b | 2845 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2846 | |
fe4b04fa PZ |
2847 | lockdep_assert_held(&ctx->mutex); |
2848 | ||
8a58ddae AS |
2849 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2850 | ||
0cda4c02 YZ |
2851 | if (event->cpu != -1) |
2852 | event->cpu = cpu; | |
c3f00c70 | 2853 | |
0b8f1e2e PZ |
2854 | /* |
2855 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2856 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2857 | */ | |
2858 | smp_store_release(&event->ctx, ctx); | |
2859 | ||
db0503e4 PZ |
2860 | /* |
2861 | * perf_event_attr::disabled events will not run and can be initialized | |
2862 | * without IPI. Except when this is the first event for the context, in | |
2863 | * that case we need the magic of the IPI to set ctx->is_active. | |
2864 | * | |
2865 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2866 | * event will issue the IPI and reprogram the hardware. | |
2867 | */ | |
2868 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2869 | raw_spin_lock_irq(&ctx->lock); | |
2870 | if (ctx->task == TASK_TOMBSTONE) { | |
2871 | raw_spin_unlock_irq(&ctx->lock); | |
2872 | return; | |
2873 | } | |
2874 | add_event_to_ctx(event, ctx); | |
2875 | raw_spin_unlock_irq(&ctx->lock); | |
2876 | return; | |
2877 | } | |
2878 | ||
a096309b PZ |
2879 | if (!task) { |
2880 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2881 | return; | |
2882 | } | |
2883 | ||
2884 | /* | |
2885 | * Should not happen, we validate the ctx is still alive before calling. | |
2886 | */ | |
2887 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2888 | return; | |
2889 | ||
39a43640 PZ |
2890 | /* |
2891 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2892 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2893 | * |
2894 | * Instead we use task_curr(), which tells us if the task is running. | |
2895 | * However, since we use task_curr() outside of rq::lock, we can race | |
2896 | * against the actual state. This means the result can be wrong. | |
2897 | * | |
2898 | * If we get a false positive, we retry, this is harmless. | |
2899 | * | |
2900 | * If we get a false negative, things are complicated. If we are after | |
2901 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2902 | * value must be correct. If we're before, it doesn't matter since | |
2903 | * perf_event_context_sched_in() will program the counter. | |
2904 | * | |
2905 | * However, this hinges on the remote context switch having observed | |
2906 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2907 | * ctx::lock in perf_event_context_sched_in(). | |
2908 | * | |
2909 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2910 | * we know any future context switch of task must see the | |
2911 | * perf_event_ctpx[] store. | |
39a43640 | 2912 | */ |
63cae12b | 2913 | |
63b6da39 | 2914 | /* |
63cae12b PZ |
2915 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2916 | * task_cpu() load, such that if the IPI then does not find the task | |
2917 | * running, a future context switch of that task must observe the | |
2918 | * store. | |
63b6da39 | 2919 | */ |
63cae12b PZ |
2920 | smp_mb(); |
2921 | again: | |
2922 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2923 | return; |
2924 | ||
2925 | raw_spin_lock_irq(&ctx->lock); | |
2926 | task = ctx->task; | |
84c4e620 | 2927 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2928 | /* |
2929 | * Cannot happen because we already checked above (which also | |
2930 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2931 | * against perf_event_exit_task_context(). | |
2932 | */ | |
63b6da39 PZ |
2933 | raw_spin_unlock_irq(&ctx->lock); |
2934 | return; | |
2935 | } | |
39a43640 | 2936 | /* |
63cae12b PZ |
2937 | * If the task is not running, ctx->lock will avoid it becoming so, |
2938 | * thus we can safely install the event. | |
39a43640 | 2939 | */ |
63cae12b PZ |
2940 | if (task_curr(task)) { |
2941 | raw_spin_unlock_irq(&ctx->lock); | |
2942 | goto again; | |
2943 | } | |
2944 | add_event_to_ctx(event, ctx); | |
2945 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2946 | } |
2947 | ||
d859e29f | 2948 | /* |
cdd6c482 | 2949 | * Cross CPU call to enable a performance event |
d859e29f | 2950 | */ |
fae3fde6 PZ |
2951 | static void __perf_event_enable(struct perf_event *event, |
2952 | struct perf_cpu_context *cpuctx, | |
2953 | struct perf_event_context *ctx, | |
2954 | void *info) | |
04289bb9 | 2955 | { |
cdd6c482 | 2956 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2957 | struct perf_event_context *task_ctx; |
04289bb9 | 2958 | |
6e801e01 PZ |
2959 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2960 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2961 | return; |
3cbed429 | 2962 | |
bd2afa49 PZ |
2963 | if (ctx->is_active) |
2964 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2965 | ||
0d3d73aa | 2966 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
33238c50 | 2967 | perf_cgroup_event_enable(event, ctx); |
04289bb9 | 2968 | |
fae3fde6 PZ |
2969 | if (!ctx->is_active) |
2970 | return; | |
2971 | ||
e5d1367f | 2972 | if (!event_filter_match(event)) { |
bd2afa49 | 2973 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2974 | return; |
e5d1367f | 2975 | } |
f4c4176f | 2976 | |
04289bb9 | 2977 | /* |
cdd6c482 | 2978 | * If the event is in a group and isn't the group leader, |
d859e29f | 2979 | * then don't put it on unless the group is on. |
04289bb9 | 2980 | */ |
bd2afa49 PZ |
2981 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2982 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2983 | return; |
bd2afa49 | 2984 | } |
fe4b04fa | 2985 | |
fae3fde6 PZ |
2986 | task_ctx = cpuctx->task_ctx; |
2987 | if (ctx->task) | |
2988 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2989 | |
487f05e1 | 2990 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2991 | } |
2992 | ||
d859e29f | 2993 | /* |
788faab7 | 2994 | * Enable an event. |
c93f7669 | 2995 | * |
cdd6c482 IM |
2996 | * If event->ctx is a cloned context, callers must make sure that |
2997 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2998 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2999 | * perf_event_for_each_child or perf_event_for_each as described |
3000 | * for perf_event_disable. | |
d859e29f | 3001 | */ |
f63a8daa | 3002 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 3003 | { |
cdd6c482 | 3004 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 3005 | |
7b648018 | 3006 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
3007 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
3008 | event->state < PERF_EVENT_STATE_ERROR) { | |
9f0c4fa1 | 3009 | out: |
7b648018 | 3010 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
3011 | return; |
3012 | } | |
3013 | ||
d859e29f | 3014 | /* |
cdd6c482 | 3015 | * If the event is in error state, clear that first. |
7b648018 PZ |
3016 | * |
3017 | * That way, if we see the event in error state below, we know that it | |
3018 | * has gone back into error state, as distinct from the task having | |
3019 | * been scheduled away before the cross-call arrived. | |
d859e29f | 3020 | */ |
9f0c4fa1 KL |
3021 | if (event->state == PERF_EVENT_STATE_ERROR) { |
3022 | /* | |
3023 | * Detached SIBLING events cannot leave ERROR state. | |
3024 | */ | |
3025 | if (event->event_caps & PERF_EV_CAP_SIBLING && | |
3026 | event->group_leader == event) | |
3027 | goto out; | |
3028 | ||
cdd6c482 | 3029 | event->state = PERF_EVENT_STATE_OFF; |
9f0c4fa1 | 3030 | } |
e625cce1 | 3031 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 3032 | |
fae3fde6 | 3033 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 3034 | } |
f63a8daa PZ |
3035 | |
3036 | /* | |
3037 | * See perf_event_disable(); | |
3038 | */ | |
3039 | void perf_event_enable(struct perf_event *event) | |
3040 | { | |
3041 | struct perf_event_context *ctx; | |
3042 | ||
3043 | ctx = perf_event_ctx_lock(event); | |
3044 | _perf_event_enable(event); | |
3045 | perf_event_ctx_unlock(event, ctx); | |
3046 | } | |
dcfce4a0 | 3047 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 3048 | |
375637bc AS |
3049 | struct stop_event_data { |
3050 | struct perf_event *event; | |
3051 | unsigned int restart; | |
3052 | }; | |
3053 | ||
95ff4ca2 AS |
3054 | static int __perf_event_stop(void *info) |
3055 | { | |
375637bc AS |
3056 | struct stop_event_data *sd = info; |
3057 | struct perf_event *event = sd->event; | |
95ff4ca2 | 3058 | |
375637bc | 3059 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
3060 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
3061 | return 0; | |
3062 | ||
3063 | /* matches smp_wmb() in event_sched_in() */ | |
3064 | smp_rmb(); | |
3065 | ||
3066 | /* | |
3067 | * There is a window with interrupts enabled before we get here, | |
3068 | * so we need to check again lest we try to stop another CPU's event. | |
3069 | */ | |
3070 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3071 | return -EAGAIN; | |
3072 | ||
3073 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3074 | ||
375637bc AS |
3075 | /* |
3076 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3077 | * but it is only used for events with AUX ring buffer, and such | |
3078 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3079 | * see comments in perf_aux_output_begin(). | |
3080 | * | |
788faab7 | 3081 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3082 | * while restarting. |
3083 | */ | |
3084 | if (sd->restart) | |
c9bbdd48 | 3085 | event->pmu->start(event, 0); |
375637bc | 3086 | |
95ff4ca2 AS |
3087 | return 0; |
3088 | } | |
3089 | ||
767ae086 | 3090 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3091 | { |
3092 | struct stop_event_data sd = { | |
3093 | .event = event, | |
767ae086 | 3094 | .restart = restart, |
375637bc AS |
3095 | }; |
3096 | int ret = 0; | |
3097 | ||
3098 | do { | |
3099 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3100 | return 0; | |
3101 | ||
3102 | /* matches smp_wmb() in event_sched_in() */ | |
3103 | smp_rmb(); | |
3104 | ||
3105 | /* | |
3106 | * We only want to restart ACTIVE events, so if the event goes | |
3107 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3108 | * fall through with ret==-ENXIO. | |
3109 | */ | |
3110 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3111 | __perf_event_stop, &sd); | |
3112 | } while (ret == -EAGAIN); | |
3113 | ||
3114 | return ret; | |
3115 | } | |
3116 | ||
3117 | /* | |
3118 | * In order to contain the amount of racy and tricky in the address filter | |
3119 | * configuration management, it is a two part process: | |
3120 | * | |
3121 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3122 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3123 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3124 | * (p2) when an event is scheduled in (pmu::add), it calls |
3125 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3126 | * if the generation has changed since the previous call. | |
3127 | * | |
3128 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3129 | * | |
3130 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3131 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3132 | * ioctl; | |
3133 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
c1e8d7c6 | 3134 | * registered mapping, called for every new mmap(), with mm::mmap_lock down |
375637bc AS |
3135 | * for reading; |
3136 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3137 | * of exec. | |
3138 | */ | |
3139 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3140 | { | |
3141 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3142 | ||
3143 | if (!has_addr_filter(event)) | |
3144 | return; | |
3145 | ||
3146 | raw_spin_lock(&ifh->lock); | |
3147 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3148 | event->pmu->addr_filters_sync(event); | |
3149 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3150 | } | |
3151 | raw_spin_unlock(&ifh->lock); | |
3152 | } | |
3153 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3154 | ||
f63a8daa | 3155 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3156 | { |
2023b359 | 3157 | /* |
cdd6c482 | 3158 | * not supported on inherited events |
2023b359 | 3159 | */ |
2e939d1d | 3160 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3161 | return -EINVAL; |
3162 | ||
cdd6c482 | 3163 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3164 | _perf_event_enable(event); |
2023b359 PZ |
3165 | |
3166 | return 0; | |
79f14641 | 3167 | } |
f63a8daa PZ |
3168 | |
3169 | /* | |
3170 | * See perf_event_disable() | |
3171 | */ | |
3172 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3173 | { | |
3174 | struct perf_event_context *ctx; | |
3175 | int ret; | |
3176 | ||
3177 | ctx = perf_event_ctx_lock(event); | |
3178 | ret = _perf_event_refresh(event, refresh); | |
3179 | perf_event_ctx_unlock(event, ctx); | |
3180 | ||
3181 | return ret; | |
3182 | } | |
26ca5c11 | 3183 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3184 | |
32ff77e8 MC |
3185 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3186 | struct perf_event_attr *attr) | |
3187 | { | |
3188 | int err; | |
3189 | ||
3190 | _perf_event_disable(bp); | |
3191 | ||
3192 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3193 | |
bf06278c | 3194 | if (!bp->attr.disabled) |
32ff77e8 | 3195 | _perf_event_enable(bp); |
bf06278c JO |
3196 | |
3197 | return err; | |
32ff77e8 MC |
3198 | } |
3199 | ||
3200 | static int perf_event_modify_attr(struct perf_event *event, | |
3201 | struct perf_event_attr *attr) | |
3202 | { | |
47f661ec ME |
3203 | int (*func)(struct perf_event *, struct perf_event_attr *); |
3204 | struct perf_event *child; | |
3205 | int err; | |
3206 | ||
32ff77e8 MC |
3207 | if (event->attr.type != attr->type) |
3208 | return -EINVAL; | |
3209 | ||
3210 | switch (event->attr.type) { | |
3211 | case PERF_TYPE_BREAKPOINT: | |
47f661ec ME |
3212 | func = perf_event_modify_breakpoint; |
3213 | break; | |
32ff77e8 MC |
3214 | default: |
3215 | /* Place holder for future additions. */ | |
3216 | return -EOPNOTSUPP; | |
3217 | } | |
47f661ec ME |
3218 | |
3219 | WARN_ON_ONCE(event->ctx->parent_ctx); | |
3220 | ||
3221 | mutex_lock(&event->child_mutex); | |
3222 | err = func(event, attr); | |
3223 | if (err) | |
3224 | goto out; | |
3225 | list_for_each_entry(child, &event->child_list, child_list) { | |
3226 | err = func(child, attr); | |
3227 | if (err) | |
3228 | goto out; | |
3229 | } | |
3230 | out: | |
3231 | mutex_unlock(&event->child_mutex); | |
3232 | return err; | |
32ff77e8 MC |
3233 | } |
3234 | ||
5b0311e1 FW |
3235 | static void ctx_sched_out(struct perf_event_context *ctx, |
3236 | struct perf_cpu_context *cpuctx, | |
3237 | enum event_type_t event_type) | |
235c7fc7 | 3238 | { |
6668128a | 3239 | struct perf_event *event, *tmp; |
db24d33e | 3240 | int is_active = ctx->is_active; |
235c7fc7 | 3241 | |
c994d613 | 3242 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3243 | |
39a43640 PZ |
3244 | if (likely(!ctx->nr_events)) { |
3245 | /* | |
3246 | * See __perf_remove_from_context(). | |
3247 | */ | |
3248 | WARN_ON_ONCE(ctx->is_active); | |
3249 | if (ctx->task) | |
3250 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3251 | return; |
39a43640 PZ |
3252 | } |
3253 | ||
db24d33e | 3254 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3255 | if (!(ctx->is_active & EVENT_ALL)) |
3256 | ctx->is_active = 0; | |
3257 | ||
63e30d3e PZ |
3258 | if (ctx->task) { |
3259 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3260 | if (!ctx->is_active) | |
3261 | cpuctx->task_ctx = NULL; | |
3262 | } | |
facc4307 | 3263 | |
8fdc6539 PZ |
3264 | /* |
3265 | * Always update time if it was set; not only when it changes. | |
3266 | * Otherwise we can 'forget' to update time for any but the last | |
3267 | * context we sched out. For example: | |
3268 | * | |
3269 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3270 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3271 | * | |
3272 | * would only update time for the pinned events. | |
3273 | */ | |
3cbaa590 PZ |
3274 | if (is_active & EVENT_TIME) { |
3275 | /* update (and stop) ctx time */ | |
3276 | update_context_time(ctx); | |
3277 | update_cgrp_time_from_cpuctx(cpuctx); | |
3278 | } | |
3279 | ||
8fdc6539 PZ |
3280 | is_active ^= ctx->is_active; /* changed bits */ |
3281 | ||
3cbaa590 | 3282 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3283 | return; |
5b0311e1 | 3284 | |
075e0b00 | 3285 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3286 | if (is_active & EVENT_PINNED) { |
6668128a | 3287 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3288 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3289 | } |
889ff015 | 3290 | |
3cbaa590 | 3291 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3292 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3293 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3294 | |
3295 | /* | |
3296 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3297 | * rotate_necessary, is will be reset by | |
3298 | * ctx_flexible_sched_in() when needed. | |
3299 | */ | |
3300 | ctx->rotate_necessary = 0; | |
9ed6060d | 3301 | } |
1b9a644f | 3302 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3303 | } |
3304 | ||
564c2b21 | 3305 | /* |
5a3126d4 PZ |
3306 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3307 | * cloned from the same version of the same context. | |
3308 | * | |
3309 | * Equivalence is measured using a generation number in the context that is | |
3310 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3311 | * and list_del_event(). | |
564c2b21 | 3312 | */ |
cdd6c482 IM |
3313 | static int context_equiv(struct perf_event_context *ctx1, |
3314 | struct perf_event_context *ctx2) | |
564c2b21 | 3315 | { |
211de6eb PZ |
3316 | lockdep_assert_held(&ctx1->lock); |
3317 | lockdep_assert_held(&ctx2->lock); | |
3318 | ||
5a3126d4 PZ |
3319 | /* Pinning disables the swap optimization */ |
3320 | if (ctx1->pin_count || ctx2->pin_count) | |
3321 | return 0; | |
3322 | ||
3323 | /* If ctx1 is the parent of ctx2 */ | |
3324 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3325 | return 1; | |
3326 | ||
3327 | /* If ctx2 is the parent of ctx1 */ | |
3328 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3329 | return 1; | |
3330 | ||
3331 | /* | |
3332 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3333 | * hierarchy, see perf_event_init_context(). | |
3334 | */ | |
3335 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3336 | ctx1->parent_gen == ctx2->parent_gen) | |
3337 | return 1; | |
3338 | ||
3339 | /* Unmatched */ | |
3340 | return 0; | |
564c2b21 PM |
3341 | } |
3342 | ||
cdd6c482 IM |
3343 | static void __perf_event_sync_stat(struct perf_event *event, |
3344 | struct perf_event *next_event) | |
bfbd3381 PZ |
3345 | { |
3346 | u64 value; | |
3347 | ||
cdd6c482 | 3348 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3349 | return; |
3350 | ||
3351 | /* | |
cdd6c482 | 3352 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3353 | * because we're in the middle of a context switch and have IRQs |
3354 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3355 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3356 | * don't need to use it. |
3357 | */ | |
0d3d73aa | 3358 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3359 | event->pmu->read(event); |
bfbd3381 | 3360 | |
0d3d73aa | 3361 | perf_event_update_time(event); |
bfbd3381 PZ |
3362 | |
3363 | /* | |
cdd6c482 | 3364 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3365 | * values when we flip the contexts. |
3366 | */ | |
e7850595 PZ |
3367 | value = local64_read(&next_event->count); |
3368 | value = local64_xchg(&event->count, value); | |
3369 | local64_set(&next_event->count, value); | |
bfbd3381 | 3370 | |
cdd6c482 IM |
3371 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3372 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3373 | |
bfbd3381 | 3374 | /* |
19d2e755 | 3375 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3376 | */ |
cdd6c482 IM |
3377 | perf_event_update_userpage(event); |
3378 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3379 | } |
3380 | ||
cdd6c482 IM |
3381 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3382 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3383 | { |
cdd6c482 | 3384 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3385 | |
3386 | if (!ctx->nr_stat) | |
3387 | return; | |
3388 | ||
02ffdbc8 PZ |
3389 | update_context_time(ctx); |
3390 | ||
cdd6c482 IM |
3391 | event = list_first_entry(&ctx->event_list, |
3392 | struct perf_event, event_entry); | |
bfbd3381 | 3393 | |
cdd6c482 IM |
3394 | next_event = list_first_entry(&next_ctx->event_list, |
3395 | struct perf_event, event_entry); | |
bfbd3381 | 3396 | |
cdd6c482 IM |
3397 | while (&event->event_entry != &ctx->event_list && |
3398 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3399 | |
cdd6c482 | 3400 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3401 | |
cdd6c482 IM |
3402 | event = list_next_entry(event, event_entry); |
3403 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3404 | } |
3405 | } | |
3406 | ||
fe4b04fa PZ |
3407 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3408 | struct task_struct *next) | |
0793a61d | 3409 | { |
8dc85d54 | 3410 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3411 | struct perf_event_context *next_ctx; |
5a3126d4 | 3412 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3413 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3414 | int do_switch = 1; |
44fae179 | 3415 | struct pmu *pmu; |
0793a61d | 3416 | |
108b02cf PZ |
3417 | if (likely(!ctx)) |
3418 | return; | |
10989fb2 | 3419 | |
44fae179 | 3420 | pmu = ctx->pmu; |
108b02cf PZ |
3421 | cpuctx = __get_cpu_context(ctx); |
3422 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3423 | return; |
3424 | ||
c93f7669 | 3425 | rcu_read_lock(); |
8dc85d54 | 3426 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3427 | if (!next_ctx) |
3428 | goto unlock; | |
3429 | ||
3430 | parent = rcu_dereference(ctx->parent_ctx); | |
3431 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3432 | ||
3433 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3434 | if (!parent && !next_parent) |
5a3126d4 PZ |
3435 | goto unlock; |
3436 | ||
3437 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3438 | /* |
3439 | * Looks like the two contexts are clones, so we might be | |
3440 | * able to optimize the context switch. We lock both | |
3441 | * contexts and check that they are clones under the | |
3442 | * lock (including re-checking that neither has been | |
3443 | * uncloned in the meantime). It doesn't matter which | |
3444 | * order we take the locks because no other cpu could | |
3445 | * be trying to lock both of these tasks. | |
3446 | */ | |
e625cce1 TG |
3447 | raw_spin_lock(&ctx->lock); |
3448 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3449 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 | 3450 | |
63b6da39 PZ |
3451 | WRITE_ONCE(ctx->task, next); |
3452 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3453 | |
44fae179 KL |
3454 | perf_pmu_disable(pmu); |
3455 | ||
3456 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3457 | pmu->sched_task(ctx, false); | |
3458 | ||
c2b98a86 AB |
3459 | /* |
3460 | * PMU specific parts of task perf context can require | |
3461 | * additional synchronization. As an example of such | |
3462 | * synchronization see implementation details of Intel | |
3463 | * LBR call stack data profiling; | |
3464 | */ | |
3465 | if (pmu->swap_task_ctx) | |
3466 | pmu->swap_task_ctx(ctx, next_ctx); | |
3467 | else | |
3468 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3469 | |
44fae179 KL |
3470 | perf_pmu_enable(pmu); |
3471 | ||
63b6da39 PZ |
3472 | /* |
3473 | * RCU_INIT_POINTER here is safe because we've not | |
3474 | * modified the ctx and the above modification of | |
3475 | * ctx->task and ctx->task_ctx_data are immaterial | |
3476 | * since those values are always verified under | |
3477 | * ctx->lock which we're now holding. | |
3478 | */ | |
3479 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3480 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3481 | ||
c93f7669 | 3482 | do_switch = 0; |
bfbd3381 | 3483 | |
cdd6c482 | 3484 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3485 | } |
e625cce1 TG |
3486 | raw_spin_unlock(&next_ctx->lock); |
3487 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3488 | } |
5a3126d4 | 3489 | unlock: |
c93f7669 | 3490 | rcu_read_unlock(); |
564c2b21 | 3491 | |
c93f7669 | 3492 | if (do_switch) { |
facc4307 | 3493 | raw_spin_lock(&ctx->lock); |
44fae179 KL |
3494 | perf_pmu_disable(pmu); |
3495 | ||
3496 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3497 | pmu->sched_task(ctx, false); | |
487f05e1 | 3498 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
44fae179 KL |
3499 | |
3500 | perf_pmu_enable(pmu); | |
facc4307 | 3501 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3502 | } |
0793a61d TG |
3503 | } |
3504 | ||
a5398bff KL |
3505 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3506 | ||
ba532500 YZ |
3507 | void perf_sched_cb_dec(struct pmu *pmu) |
3508 | { | |
e48c1788 PZ |
3509 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3510 | ||
a5398bff KL |
3511 | this_cpu_dec(perf_sched_cb_usages); |
3512 | ||
3513 | if (!--cpuctx->sched_cb_usage) | |
3514 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3515 | } |
3516 | ||
e48c1788 | 3517 | |
ba532500 YZ |
3518 | void perf_sched_cb_inc(struct pmu *pmu) |
3519 | { | |
e48c1788 PZ |
3520 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3521 | ||
a5398bff KL |
3522 | if (!cpuctx->sched_cb_usage++) |
3523 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3524 | ||
3525 | this_cpu_inc(perf_sched_cb_usages); | |
ba532500 YZ |
3526 | } |
3527 | ||
3528 | /* | |
3529 | * This function provides the context switch callback to the lower code | |
3530 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3531 | * |
3532 | * This callback is relevant even to per-cpu events; for example multi event | |
3533 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3534 | * all queued PEBS records before we context switch to a new task. | |
ba532500 | 3535 | */ |
556cccad KL |
3536 | static void __perf_pmu_sched_task(struct perf_cpu_context *cpuctx, bool sched_in) |
3537 | { | |
3538 | struct pmu *pmu; | |
3539 | ||
3540 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ | |
3541 | ||
3542 | if (WARN_ON_ONCE(!pmu->sched_task)) | |
3543 | return; | |
3544 | ||
3545 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
3546 | perf_pmu_disable(pmu); | |
3547 | ||
3548 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
3549 | ||
3550 | perf_pmu_enable(pmu); | |
3551 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
3552 | } | |
3553 | ||
a5398bff KL |
3554 | static void perf_pmu_sched_task(struct task_struct *prev, |
3555 | struct task_struct *next, | |
3556 | bool sched_in) | |
3557 | { | |
3558 | struct perf_cpu_context *cpuctx; | |
3559 | ||
3560 | if (prev == next) | |
3561 | return; | |
3562 | ||
3563 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { | |
3564 | /* will be handled in perf_event_context_sched_in/out */ | |
3565 | if (cpuctx->task_ctx) | |
3566 | continue; | |
3567 | ||
3568 | __perf_pmu_sched_task(cpuctx, sched_in); | |
3569 | } | |
3570 | } | |
3571 | ||
45ac1403 AH |
3572 | static void perf_event_switch(struct task_struct *task, |
3573 | struct task_struct *next_prev, bool sched_in); | |
3574 | ||
8dc85d54 PZ |
3575 | #define for_each_task_context_nr(ctxn) \ |
3576 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3577 | ||
3578 | /* | |
3579 | * Called from scheduler to remove the events of the current task, | |
3580 | * with interrupts disabled. | |
3581 | * | |
3582 | * We stop each event and update the event value in event->count. | |
3583 | * | |
3584 | * This does not protect us against NMI, but disable() | |
3585 | * sets the disabled bit in the control field of event _before_ | |
3586 | * accessing the event control register. If a NMI hits, then it will | |
3587 | * not restart the event. | |
3588 | */ | |
ab0cce56 JO |
3589 | void __perf_event_task_sched_out(struct task_struct *task, |
3590 | struct task_struct *next) | |
8dc85d54 PZ |
3591 | { |
3592 | int ctxn; | |
3593 | ||
a5398bff KL |
3594 | if (__this_cpu_read(perf_sched_cb_usages)) |
3595 | perf_pmu_sched_task(task, next, false); | |
3596 | ||
45ac1403 AH |
3597 | if (atomic_read(&nr_switch_events)) |
3598 | perf_event_switch(task, next, false); | |
3599 | ||
8dc85d54 PZ |
3600 | for_each_task_context_nr(ctxn) |
3601 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3602 | |
3603 | /* | |
3604 | * if cgroup events exist on this CPU, then we need | |
3605 | * to check if we have to switch out PMU state. | |
3606 | * cgroup event are system-wide mode only | |
3607 | */ | |
4a32fea9 | 3608 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3609 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3610 | } |
3611 | ||
5b0311e1 FW |
3612 | /* |
3613 | * Called with IRQs disabled | |
3614 | */ | |
3615 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3616 | enum event_type_t event_type) | |
3617 | { | |
3618 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3619 | } |
3620 | ||
6eef8a71 | 3621 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3622 | { |
24fb6b8e IR |
3623 | const struct perf_event *le = *(const struct perf_event **)l; |
3624 | const struct perf_event *re = *(const struct perf_event **)r; | |
6eef8a71 IR |
3625 | |
3626 | return le->group_index < re->group_index; | |
3627 | } | |
3628 | ||
3629 | static void swap_ptr(void *l, void *r) | |
3630 | { | |
3631 | void **lp = l, **rp = r; | |
3632 | ||
3633 | swap(*lp, *rp); | |
3634 | } | |
3635 | ||
3636 | static const struct min_heap_callbacks perf_min_heap = { | |
3637 | .elem_size = sizeof(struct perf_event *), | |
3638 | .less = perf_less_group_idx, | |
3639 | .swp = swap_ptr, | |
3640 | }; | |
3641 | ||
3642 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3643 | { | |
3644 | struct perf_event **itrs = heap->data; | |
3645 | ||
3646 | if (event) { | |
3647 | itrs[heap->nr] = event; | |
3648 | heap->nr++; | |
3649 | } | |
3650 | } | |
3651 | ||
836196be IR |
3652 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3653 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3654 | int (*func)(struct perf_event *, void *), |
3655 | void *data) | |
3656 | { | |
95ed6c70 IR |
3657 | #ifdef CONFIG_CGROUP_PERF |
3658 | struct cgroup_subsys_state *css = NULL; | |
3659 | #endif | |
6eef8a71 IR |
3660 | /* Space for per CPU and/or any CPU event iterators. */ |
3661 | struct perf_event *itrs[2]; | |
836196be IR |
3662 | struct min_heap event_heap; |
3663 | struct perf_event **evt; | |
1cac7b1a | 3664 | int ret; |
8e1a2031 | 3665 | |
836196be IR |
3666 | if (cpuctx) { |
3667 | event_heap = (struct min_heap){ | |
3668 | .data = cpuctx->heap, | |
3669 | .nr = 0, | |
3670 | .size = cpuctx->heap_size, | |
3671 | }; | |
c2283c93 IR |
3672 | |
3673 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3674 | |
3675 | #ifdef CONFIG_CGROUP_PERF | |
3676 | if (cpuctx->cgrp) | |
3677 | css = &cpuctx->cgrp->css; | |
3678 | #endif | |
836196be IR |
3679 | } else { |
3680 | event_heap = (struct min_heap){ | |
3681 | .data = itrs, | |
3682 | .nr = 0, | |
3683 | .size = ARRAY_SIZE(itrs), | |
3684 | }; | |
3685 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3686 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3687 | } |
3688 | evt = event_heap.data; | |
3689 | ||
95ed6c70 IR |
3690 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3691 | ||
3692 | #ifdef CONFIG_CGROUP_PERF | |
3693 | for (; css; css = css->parent) | |
3694 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3695 | #endif | |
1cac7b1a | 3696 | |
6eef8a71 | 3697 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3698 | |
6eef8a71 | 3699 | while (event_heap.nr) { |
1cac7b1a PZ |
3700 | ret = func(*evt, data); |
3701 | if (ret) | |
3702 | return ret; | |
3703 | ||
3704 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3705 | if (*evt) |
3706 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3707 | else | |
3708 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3709 | } |
0793a61d | 3710 | |
1cac7b1a PZ |
3711 | return 0; |
3712 | } | |
3713 | ||
ab6f824c | 3714 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3715 | { |
2c2366c7 PZ |
3716 | struct perf_event_context *ctx = event->ctx; |
3717 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3718 | int *can_add_hw = data; | |
ab6f824c | 3719 | |
1cac7b1a PZ |
3720 | if (event->state <= PERF_EVENT_STATE_OFF) |
3721 | return 0; | |
3722 | ||
3723 | if (!event_filter_match(event)) | |
3724 | return 0; | |
3725 | ||
2c2366c7 PZ |
3726 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3727 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3728 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3729 | } |
1cac7b1a | 3730 | |
ab6f824c | 3731 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
33238c50 PZ |
3732 | if (event->attr.pinned) { |
3733 | perf_cgroup_event_disable(event, ctx); | |
ab6f824c | 3734 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); |
33238c50 | 3735 | } |
1cac7b1a | 3736 | |
2c2366c7 PZ |
3737 | *can_add_hw = 0; |
3738 | ctx->rotate_necessary = 1; | |
2714c396 | 3739 | perf_mux_hrtimer_restart(cpuctx); |
3b6f9e5c | 3740 | } |
1cac7b1a PZ |
3741 | |
3742 | return 0; | |
5b0311e1 FW |
3743 | } |
3744 | ||
3745 | static void | |
1cac7b1a PZ |
3746 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3747 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3748 | { |
2c2366c7 | 3749 | int can_add_hw = 1; |
3b6f9e5c | 3750 | |
836196be IR |
3751 | if (ctx != &cpuctx->ctx) |
3752 | cpuctx = NULL; | |
3753 | ||
3754 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3755 | smp_processor_id(), |
2c2366c7 | 3756 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3757 | } |
8e1a2031 | 3758 | |
1cac7b1a PZ |
3759 | static void |
3760 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3761 | struct perf_cpu_context *cpuctx) | |
3762 | { | |
2c2366c7 | 3763 | int can_add_hw = 1; |
0793a61d | 3764 | |
836196be IR |
3765 | if (ctx != &cpuctx->ctx) |
3766 | cpuctx = NULL; | |
3767 | ||
3768 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3769 | smp_processor_id(), |
2c2366c7 | 3770 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3771 | } |
3772 | ||
3773 | static void | |
3774 | ctx_sched_in(struct perf_event_context *ctx, | |
3775 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3776 | enum event_type_t event_type, |
3777 | struct task_struct *task) | |
5b0311e1 | 3778 | { |
db24d33e | 3779 | int is_active = ctx->is_active; |
c994d613 PZ |
3780 | u64 now; |
3781 | ||
3782 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3783 | |
5b0311e1 | 3784 | if (likely(!ctx->nr_events)) |
facc4307 | 3785 | return; |
5b0311e1 | 3786 | |
3cbaa590 | 3787 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3788 | if (ctx->task) { |
3789 | if (!is_active) | |
3790 | cpuctx->task_ctx = ctx; | |
3791 | else | |
3792 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3793 | } | |
3794 | ||
3cbaa590 PZ |
3795 | is_active ^= ctx->is_active; /* changed bits */ |
3796 | ||
3797 | if (is_active & EVENT_TIME) { | |
3798 | /* start ctx time */ | |
3799 | now = perf_clock(); | |
3800 | ctx->timestamp = now; | |
3801 | perf_cgroup_set_timestamp(task, ctx); | |
3802 | } | |
3803 | ||
5b0311e1 FW |
3804 | /* |
3805 | * First go through the list and put on any pinned groups | |
3806 | * in order to give them the best chance of going on. | |
3807 | */ | |
3cbaa590 | 3808 | if (is_active & EVENT_PINNED) |
6e37738a | 3809 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3810 | |
3811 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3812 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3813 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3814 | } |
3815 | ||
329c0e01 | 3816 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3817 | enum event_type_t event_type, |
3818 | struct task_struct *task) | |
329c0e01 FW |
3819 | { |
3820 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3821 | ||
e5d1367f | 3822 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3823 | } |
3824 | ||
e5d1367f SE |
3825 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3826 | struct task_struct *task) | |
235c7fc7 | 3827 | { |
108b02cf | 3828 | struct perf_cpu_context *cpuctx; |
556cccad | 3829 | struct pmu *pmu = ctx->pmu; |
235c7fc7 | 3830 | |
108b02cf | 3831 | cpuctx = __get_cpu_context(ctx); |
556cccad KL |
3832 | if (cpuctx->task_ctx == ctx) { |
3833 | if (cpuctx->sched_cb_usage) | |
3834 | __perf_pmu_sched_task(cpuctx, true); | |
329c0e01 | 3835 | return; |
556cccad | 3836 | } |
329c0e01 | 3837 | |
facc4307 | 3838 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3839 | /* |
3840 | * We must check ctx->nr_events while holding ctx->lock, such | |
3841 | * that we serialize against perf_install_in_context(). | |
3842 | */ | |
3843 | if (!ctx->nr_events) | |
3844 | goto unlock; | |
3845 | ||
556cccad | 3846 | perf_pmu_disable(pmu); |
329c0e01 FW |
3847 | /* |
3848 | * We want to keep the following priority order: | |
3849 | * cpu pinned (that don't need to move), task pinned, | |
3850 | * cpu flexible, task flexible. | |
fe45bafb AS |
3851 | * |
3852 | * However, if task's ctx is not carrying any pinned | |
3853 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3854 | */ |
8e1a2031 | 3855 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3856 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3857 | perf_event_sched_in(cpuctx, ctx, task); |
556cccad KL |
3858 | |
3859 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3860 | pmu->sched_task(cpuctx->task_ctx, true); | |
3861 | ||
3862 | perf_pmu_enable(pmu); | |
fdccc3fb | 3863 | |
3864 | unlock: | |
facc4307 | 3865 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3866 | } |
3867 | ||
8dc85d54 PZ |
3868 | /* |
3869 | * Called from scheduler to add the events of the current task | |
3870 | * with interrupts disabled. | |
3871 | * | |
3872 | * We restore the event value and then enable it. | |
3873 | * | |
3874 | * This does not protect us against NMI, but enable() | |
3875 | * sets the enabled bit in the control field of event _before_ | |
3876 | * accessing the event control register. If a NMI hits, then it will | |
3877 | * keep the event running. | |
3878 | */ | |
ab0cce56 JO |
3879 | void __perf_event_task_sched_in(struct task_struct *prev, |
3880 | struct task_struct *task) | |
8dc85d54 PZ |
3881 | { |
3882 | struct perf_event_context *ctx; | |
3883 | int ctxn; | |
3884 | ||
7e41d177 PZ |
3885 | /* |
3886 | * If cgroup events exist on this CPU, then we need to check if we have | |
3887 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3888 | * | |
3889 | * Since cgroup events are CPU events, we must schedule these in before | |
3890 | * we schedule in the task events. | |
3891 | */ | |
3892 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3893 | perf_cgroup_sched_in(prev, task); | |
3894 | ||
8dc85d54 PZ |
3895 | for_each_task_context_nr(ctxn) { |
3896 | ctx = task->perf_event_ctxp[ctxn]; | |
3897 | if (likely(!ctx)) | |
3898 | continue; | |
3899 | ||
e5d1367f | 3900 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3901 | } |
d010b332 | 3902 | |
45ac1403 AH |
3903 | if (atomic_read(&nr_switch_events)) |
3904 | perf_event_switch(task, prev, true); | |
a5398bff KL |
3905 | |
3906 | if (__this_cpu_read(perf_sched_cb_usages)) | |
3907 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3908 | } |
3909 | ||
abd50713 PZ |
3910 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3911 | { | |
3912 | u64 frequency = event->attr.sample_freq; | |
3913 | u64 sec = NSEC_PER_SEC; | |
3914 | u64 divisor, dividend; | |
3915 | ||
3916 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3917 | ||
3918 | count_fls = fls64(count); | |
3919 | nsec_fls = fls64(nsec); | |
3920 | frequency_fls = fls64(frequency); | |
3921 | sec_fls = 30; | |
3922 | ||
3923 | /* | |
3924 | * We got @count in @nsec, with a target of sample_freq HZ | |
3925 | * the target period becomes: | |
3926 | * | |
3927 | * @count * 10^9 | |
3928 | * period = ------------------- | |
3929 | * @nsec * sample_freq | |
3930 | * | |
3931 | */ | |
3932 | ||
3933 | /* | |
3934 | * Reduce accuracy by one bit such that @a and @b converge | |
3935 | * to a similar magnitude. | |
3936 | */ | |
fe4b04fa | 3937 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3938 | do { \ |
3939 | if (a##_fls > b##_fls) { \ | |
3940 | a >>= 1; \ | |
3941 | a##_fls--; \ | |
3942 | } else { \ | |
3943 | b >>= 1; \ | |
3944 | b##_fls--; \ | |
3945 | } \ | |
3946 | } while (0) | |
3947 | ||
3948 | /* | |
3949 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3950 | * the other, so that finally we can do a u64/u64 division. | |
3951 | */ | |
3952 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3953 | REDUCE_FLS(nsec, frequency); | |
3954 | REDUCE_FLS(sec, count); | |
3955 | } | |
3956 | ||
3957 | if (count_fls + sec_fls > 64) { | |
3958 | divisor = nsec * frequency; | |
3959 | ||
3960 | while (count_fls + sec_fls > 64) { | |
3961 | REDUCE_FLS(count, sec); | |
3962 | divisor >>= 1; | |
3963 | } | |
3964 | ||
3965 | dividend = count * sec; | |
3966 | } else { | |
3967 | dividend = count * sec; | |
3968 | ||
3969 | while (nsec_fls + frequency_fls > 64) { | |
3970 | REDUCE_FLS(nsec, frequency); | |
3971 | dividend >>= 1; | |
3972 | } | |
3973 | ||
3974 | divisor = nsec * frequency; | |
3975 | } | |
3976 | ||
f6ab91ad PZ |
3977 | if (!divisor) |
3978 | return dividend; | |
3979 | ||
abd50713 PZ |
3980 | return div64_u64(dividend, divisor); |
3981 | } | |
3982 | ||
e050e3f0 SE |
3983 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3984 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3985 | ||
f39d47ff | 3986 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3987 | { |
cdd6c482 | 3988 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3989 | s64 period, sample_period; |
bd2b5b12 PZ |
3990 | s64 delta; |
3991 | ||
abd50713 | 3992 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3993 | |
3994 | delta = (s64)(period - hwc->sample_period); | |
3995 | delta = (delta + 7) / 8; /* low pass filter */ | |
3996 | ||
3997 | sample_period = hwc->sample_period + delta; | |
3998 | ||
3999 | if (!sample_period) | |
4000 | sample_period = 1; | |
4001 | ||
bd2b5b12 | 4002 | hwc->sample_period = sample_period; |
abd50713 | 4003 | |
e7850595 | 4004 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
4005 | if (disable) |
4006 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4007 | ||
e7850595 | 4008 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
4009 | |
4010 | if (disable) | |
4011 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 4012 | } |
bd2b5b12 PZ |
4013 | } |
4014 | ||
e050e3f0 SE |
4015 | /* |
4016 | * combine freq adjustment with unthrottling to avoid two passes over the | |
4017 | * events. At the same time, make sure, having freq events does not change | |
4018 | * the rate of unthrottling as that would introduce bias. | |
4019 | */ | |
4020 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
4021 | int needs_unthr) | |
60db5e09 | 4022 | { |
cdd6c482 IM |
4023 | struct perf_event *event; |
4024 | struct hw_perf_event *hwc; | |
e050e3f0 | 4025 | u64 now, period = TICK_NSEC; |
abd50713 | 4026 | s64 delta; |
60db5e09 | 4027 | |
e050e3f0 SE |
4028 | /* |
4029 | * only need to iterate over all events iff: | |
4030 | * - context have events in frequency mode (needs freq adjust) | |
4031 | * - there are events to unthrottle on this cpu | |
4032 | */ | |
4033 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
4034 | return; |
4035 | ||
e050e3f0 | 4036 | raw_spin_lock(&ctx->lock); |
f39d47ff | 4037 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 4038 | |
03541f8b | 4039 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 4040 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
4041 | continue; |
4042 | ||
5632ab12 | 4043 | if (!event_filter_match(event)) |
5d27c23d PZ |
4044 | continue; |
4045 | ||
44377277 AS |
4046 | perf_pmu_disable(event->pmu); |
4047 | ||
cdd6c482 | 4048 | hwc = &event->hw; |
6a24ed6c | 4049 | |
ae23bff1 | 4050 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 4051 | hwc->interrupts = 0; |
cdd6c482 | 4052 | perf_log_throttle(event, 1); |
a4eaf7f1 | 4053 | event->pmu->start(event, 0); |
a78ac325 PZ |
4054 | } |
4055 | ||
cdd6c482 | 4056 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 4057 | goto next; |
60db5e09 | 4058 | |
e050e3f0 SE |
4059 | /* |
4060 | * stop the event and update event->count | |
4061 | */ | |
4062 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4063 | ||
e7850595 | 4064 | now = local64_read(&event->count); |
abd50713 PZ |
4065 | delta = now - hwc->freq_count_stamp; |
4066 | hwc->freq_count_stamp = now; | |
60db5e09 | 4067 | |
e050e3f0 SE |
4068 | /* |
4069 | * restart the event | |
4070 | * reload only if value has changed | |
f39d47ff SE |
4071 | * we have stopped the event so tell that |
4072 | * to perf_adjust_period() to avoid stopping it | |
4073 | * twice. | |
e050e3f0 | 4074 | */ |
abd50713 | 4075 | if (delta > 0) |
f39d47ff | 4076 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
4077 | |
4078 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
4079 | next: |
4080 | perf_pmu_enable(event->pmu); | |
60db5e09 | 4081 | } |
e050e3f0 | 4082 | |
f39d47ff | 4083 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 4084 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
4085 | } |
4086 | ||
235c7fc7 | 4087 | /* |
8703a7cf | 4088 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 4089 | */ |
8703a7cf | 4090 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 4091 | { |
dddd3379 TG |
4092 | /* |
4093 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
4094 | * disabled by the inheritance code. | |
4095 | */ | |
8703a7cf PZ |
4096 | if (ctx->rotate_disable) |
4097 | return; | |
8e1a2031 | 4098 | |
8703a7cf PZ |
4099 | perf_event_groups_delete(&ctx->flexible_groups, event); |
4100 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
4101 | } |
4102 | ||
7fa343b7 | 4103 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 4104 | static inline struct perf_event * |
7fa343b7 | 4105 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 4106 | { |
7fa343b7 SL |
4107 | struct perf_event *event; |
4108 | ||
4109 | /* pick the first active flexible event */ | |
4110 | event = list_first_entry_or_null(&ctx->flexible_active, | |
4111 | struct perf_event, active_list); | |
4112 | ||
4113 | /* if no active flexible event, pick the first event */ | |
4114 | if (!event) { | |
4115 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
4116 | typeof(*event), group_node); | |
4117 | } | |
4118 | ||
90c91dfb PZ |
4119 | /* |
4120 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
4121 | * finds there are unschedulable events, it will set it again. | |
4122 | */ | |
4123 | ctx->rotate_necessary = 0; | |
4124 | ||
7fa343b7 | 4125 | return event; |
8d5bce0c PZ |
4126 | } |
4127 | ||
4128 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4129 | { | |
4130 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4131 | struct perf_event_context *task_ctx = NULL; |
4132 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4133 | |
4134 | /* | |
4135 | * Since we run this from IRQ context, nobody can install new | |
4136 | * events, thus the event count values are stable. | |
4137 | */ | |
7fc23a53 | 4138 | |
fd7d5517 IR |
4139 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4140 | task_ctx = cpuctx->task_ctx; | |
4141 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4142 | |
8d5bce0c PZ |
4143 | if (!(cpu_rotate || task_rotate)) |
4144 | return false; | |
0f5a2601 | 4145 | |
facc4307 | 4146 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4147 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4148 | |
8d5bce0c | 4149 | if (task_rotate) |
7fa343b7 | 4150 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4151 | if (cpu_rotate) |
7fa343b7 | 4152 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4153 | |
8d5bce0c PZ |
4154 | /* |
4155 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4156 | * and then, if needed CPU flexible. | |
4157 | */ | |
fd7d5517 IR |
4158 | if (task_event || (task_ctx && cpu_event)) |
4159 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4160 | if (cpu_event) |
4161 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4162 | |
8d5bce0c | 4163 | if (task_event) |
fd7d5517 | 4164 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4165 | if (cpu_event) |
4166 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4167 | |
fd7d5517 | 4168 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4169 | |
0f5a2601 PZ |
4170 | perf_pmu_enable(cpuctx->ctx.pmu); |
4171 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4172 | |
8d5bce0c | 4173 | return true; |
e9d2b064 PZ |
4174 | } |
4175 | ||
4176 | void perf_event_task_tick(void) | |
4177 | { | |
2fde4f94 MR |
4178 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4179 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4180 | int throttled; |
b5ab4cd5 | 4181 | |
16444645 | 4182 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4183 | |
e050e3f0 SE |
4184 | __this_cpu_inc(perf_throttled_seq); |
4185 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4186 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4187 | |
2fde4f94 | 4188 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4189 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4190 | } |
4191 | ||
889ff015 FW |
4192 | static int event_enable_on_exec(struct perf_event *event, |
4193 | struct perf_event_context *ctx) | |
4194 | { | |
4195 | if (!event->attr.enable_on_exec) | |
4196 | return 0; | |
4197 | ||
4198 | event->attr.enable_on_exec = 0; | |
4199 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4200 | return 0; | |
4201 | ||
0d3d73aa | 4202 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4203 | |
4204 | return 1; | |
4205 | } | |
4206 | ||
57e7986e | 4207 | /* |
cdd6c482 | 4208 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4209 | * This expects task == current. |
4210 | */ | |
c1274499 | 4211 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4212 | { |
c1274499 | 4213 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4214 | enum event_type_t event_type = 0; |
3e349507 | 4215 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4216 | struct perf_event *event; |
57e7986e PM |
4217 | unsigned long flags; |
4218 | int enabled = 0; | |
4219 | ||
4220 | local_irq_save(flags); | |
c1274499 | 4221 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4222 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4223 | goto out; |
4224 | ||
3e349507 PZ |
4225 | cpuctx = __get_cpu_context(ctx); |
4226 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4227 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4228 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4229 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4230 | event_type |= get_event_type(event); |
4231 | } | |
57e7986e PM |
4232 | |
4233 | /* | |
3e349507 | 4234 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4235 | */ |
3e349507 | 4236 | if (enabled) { |
211de6eb | 4237 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4238 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4239 | } else { |
4240 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4241 | } |
4242 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4243 | |
9ed6060d | 4244 | out: |
57e7986e | 4245 | local_irq_restore(flags); |
211de6eb PZ |
4246 | |
4247 | if (clone_ctx) | |
4248 | put_ctx(clone_ctx); | |
57e7986e PM |
4249 | } |
4250 | ||
2e498d0a ME |
4251 | static void perf_remove_from_owner(struct perf_event *event); |
4252 | static void perf_event_exit_event(struct perf_event *event, | |
4253 | struct perf_event_context *ctx); | |
4254 | ||
4255 | /* | |
4256 | * Removes all events from the current task that have been marked | |
4257 | * remove-on-exec, and feeds their values back to parent events. | |
4258 | */ | |
4259 | static void perf_event_remove_on_exec(int ctxn) | |
4260 | { | |
4261 | struct perf_event_context *ctx, *clone_ctx = NULL; | |
4262 | struct perf_event *event, *next; | |
4263 | LIST_HEAD(free_list); | |
4264 | unsigned long flags; | |
4265 | bool modified = false; | |
4266 | ||
4267 | ctx = perf_pin_task_context(current, ctxn); | |
4268 | if (!ctx) | |
4269 | return; | |
4270 | ||
4271 | mutex_lock(&ctx->mutex); | |
4272 | ||
4273 | if (WARN_ON_ONCE(ctx->task != current)) | |
4274 | goto unlock; | |
4275 | ||
4276 | list_for_each_entry_safe(event, next, &ctx->event_list, event_entry) { | |
4277 | if (!event->attr.remove_on_exec) | |
4278 | continue; | |
4279 | ||
4280 | if (!is_kernel_event(event)) | |
4281 | perf_remove_from_owner(event); | |
4282 | ||
4283 | modified = true; | |
4284 | ||
4285 | perf_event_exit_event(event, ctx); | |
4286 | } | |
4287 | ||
4288 | raw_spin_lock_irqsave(&ctx->lock, flags); | |
4289 | if (modified) | |
4290 | clone_ctx = unclone_ctx(ctx); | |
4291 | --ctx->pin_count; | |
4292 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4293 | ||
4294 | unlock: | |
4295 | mutex_unlock(&ctx->mutex); | |
4296 | ||
4297 | put_ctx(ctx); | |
4298 | if (clone_ctx) | |
4299 | put_ctx(clone_ctx); | |
4300 | } | |
4301 | ||
0492d4c5 PZ |
4302 | struct perf_read_data { |
4303 | struct perf_event *event; | |
4304 | bool group; | |
7d88962e | 4305 | int ret; |
0492d4c5 PZ |
4306 | }; |
4307 | ||
451d24d1 | 4308 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4309 | { |
d6a2f903 DCC |
4310 | u16 local_pkg, event_pkg; |
4311 | ||
4312 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4313 | int local_cpu = smp_processor_id(); |
4314 | ||
4315 | event_pkg = topology_physical_package_id(event_cpu); | |
4316 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4317 | |
4318 | if (event_pkg == local_pkg) | |
4319 | return local_cpu; | |
4320 | } | |
4321 | ||
4322 | return event_cpu; | |
4323 | } | |
4324 | ||
0793a61d | 4325 | /* |
cdd6c482 | 4326 | * Cross CPU call to read the hardware event |
0793a61d | 4327 | */ |
cdd6c482 | 4328 | static void __perf_event_read(void *info) |
0793a61d | 4329 | { |
0492d4c5 PZ |
4330 | struct perf_read_data *data = info; |
4331 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4332 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4333 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4334 | struct pmu *pmu = event->pmu; |
621a01ea | 4335 | |
e1ac3614 PM |
4336 | /* |
4337 | * If this is a task context, we need to check whether it is | |
4338 | * the current task context of this cpu. If not it has been | |
4339 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4340 | * event->count would have been updated to a recent sample |
4341 | * when the event was scheduled out. | |
e1ac3614 PM |
4342 | */ |
4343 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4344 | return; | |
4345 | ||
e625cce1 | 4346 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4347 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4348 | update_context_time(ctx); |
e5d1367f SE |
4349 | update_cgrp_time_from_event(event); |
4350 | } | |
0492d4c5 | 4351 | |
0d3d73aa PZ |
4352 | perf_event_update_time(event); |
4353 | if (data->group) | |
4354 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4355 | |
4a00c16e SB |
4356 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4357 | goto unlock; | |
0492d4c5 | 4358 | |
4a00c16e SB |
4359 | if (!data->group) { |
4360 | pmu->read(event); | |
4361 | data->ret = 0; | |
0492d4c5 | 4362 | goto unlock; |
4a00c16e SB |
4363 | } |
4364 | ||
4365 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4366 | ||
4367 | pmu->read(event); | |
0492d4c5 | 4368 | |
edb39592 | 4369 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4370 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4371 | /* | |
4372 | * Use sibling's PMU rather than @event's since | |
4373 | * sibling could be on different (eg: software) PMU. | |
4374 | */ | |
0492d4c5 | 4375 | sub->pmu->read(sub); |
4a00c16e | 4376 | } |
0492d4c5 | 4377 | } |
4a00c16e SB |
4378 | |
4379 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4380 | |
4381 | unlock: | |
e625cce1 | 4382 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4383 | } |
4384 | ||
b5e58793 PZ |
4385 | static inline u64 perf_event_count(struct perf_event *event) |
4386 | { | |
c39a0e2c | 4387 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4388 | } |
4389 | ||
ffe8690c KX |
4390 | /* |
4391 | * NMI-safe method to read a local event, that is an event that | |
4392 | * is: | |
4393 | * - either for the current task, or for this CPU | |
4394 | * - does not have inherit set, for inherited task events | |
4395 | * will not be local and we cannot read them atomically | |
4396 | * - must not have a pmu::count method | |
4397 | */ | |
7d9285e8 YS |
4398 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4399 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4400 | { |
4401 | unsigned long flags; | |
f91840a3 | 4402 | int ret = 0; |
ffe8690c KX |
4403 | |
4404 | /* | |
4405 | * Disabling interrupts avoids all counter scheduling (context | |
4406 | * switches, timer based rotation and IPIs). | |
4407 | */ | |
4408 | local_irq_save(flags); | |
4409 | ||
ffe8690c KX |
4410 | /* |
4411 | * It must not be an event with inherit set, we cannot read | |
4412 | * all child counters from atomic context. | |
4413 | */ | |
f91840a3 AS |
4414 | if (event->attr.inherit) { |
4415 | ret = -EOPNOTSUPP; | |
4416 | goto out; | |
4417 | } | |
ffe8690c | 4418 | |
f91840a3 AS |
4419 | /* If this is a per-task event, it must be for current */ |
4420 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4421 | event->hw.target != current) { | |
4422 | ret = -EINVAL; | |
4423 | goto out; | |
4424 | } | |
4425 | ||
4426 | /* If this is a per-CPU event, it must be for this CPU */ | |
4427 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4428 | event->cpu != smp_processor_id()) { | |
4429 | ret = -EINVAL; | |
4430 | goto out; | |
4431 | } | |
ffe8690c | 4432 | |
befb1b3c RC |
4433 | /* If this is a pinned event it must be running on this CPU */ |
4434 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4435 | ret = -EBUSY; | |
4436 | goto out; | |
4437 | } | |
4438 | ||
ffe8690c KX |
4439 | /* |
4440 | * If the event is currently on this CPU, its either a per-task event, | |
4441 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4442 | * oncpu == -1). | |
4443 | */ | |
4444 | if (event->oncpu == smp_processor_id()) | |
4445 | event->pmu->read(event); | |
4446 | ||
f91840a3 | 4447 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4448 | if (enabled || running) { |
4449 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4450 | u64 __enabled, __running; | |
4451 | ||
4452 | __perf_update_times(event, now, &__enabled, &__running); | |
4453 | if (enabled) | |
4454 | *enabled = __enabled; | |
4455 | if (running) | |
4456 | *running = __running; | |
4457 | } | |
f91840a3 | 4458 | out: |
ffe8690c KX |
4459 | local_irq_restore(flags); |
4460 | ||
f91840a3 | 4461 | return ret; |
ffe8690c KX |
4462 | } |
4463 | ||
7d88962e | 4464 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4465 | { |
0c1cbc18 | 4466 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4467 | int event_cpu, ret = 0; |
7d88962e | 4468 | |
0793a61d | 4469 | /* |
cdd6c482 IM |
4470 | * If event is enabled and currently active on a CPU, update the |
4471 | * value in the event structure: | |
0793a61d | 4472 | */ |
0c1cbc18 PZ |
4473 | again: |
4474 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4475 | struct perf_read_data data; | |
4476 | ||
4477 | /* | |
4478 | * Orders the ->state and ->oncpu loads such that if we see | |
4479 | * ACTIVE we must also see the right ->oncpu. | |
4480 | * | |
4481 | * Matches the smp_wmb() from event_sched_in(). | |
4482 | */ | |
4483 | smp_rmb(); | |
d6a2f903 | 4484 | |
451d24d1 PZ |
4485 | event_cpu = READ_ONCE(event->oncpu); |
4486 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4487 | return 0; | |
4488 | ||
0c1cbc18 PZ |
4489 | data = (struct perf_read_data){ |
4490 | .event = event, | |
4491 | .group = group, | |
4492 | .ret = 0, | |
4493 | }; | |
4494 | ||
451d24d1 PZ |
4495 | preempt_disable(); |
4496 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4497 | |
58763148 PZ |
4498 | /* |
4499 | * Purposely ignore the smp_call_function_single() return | |
4500 | * value. | |
4501 | * | |
451d24d1 | 4502 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4503 | * scheduled out and that will have updated the event count. |
4504 | * | |
4505 | * Therefore, either way, we'll have an up-to-date event count | |
4506 | * after this. | |
4507 | */ | |
451d24d1 PZ |
4508 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4509 | preempt_enable(); | |
58763148 | 4510 | ret = data.ret; |
0c1cbc18 PZ |
4511 | |
4512 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4513 | struct perf_event_context *ctx = event->ctx; |
4514 | unsigned long flags; | |
4515 | ||
e625cce1 | 4516 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4517 | state = event->state; |
4518 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4519 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4520 | goto again; | |
4521 | } | |
4522 | ||
c530ccd9 | 4523 | /* |
0c1cbc18 PZ |
4524 | * May read while context is not active (e.g., thread is |
4525 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4526 | */ |
0c1cbc18 | 4527 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4528 | update_context_time(ctx); |
e5d1367f SE |
4529 | update_cgrp_time_from_event(event); |
4530 | } | |
0c1cbc18 | 4531 | |
0d3d73aa | 4532 | perf_event_update_time(event); |
0492d4c5 | 4533 | if (group) |
0d3d73aa | 4534 | perf_event_update_sibling_time(event); |
e625cce1 | 4535 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4536 | } |
7d88962e SB |
4537 | |
4538 | return ret; | |
0793a61d TG |
4539 | } |
4540 | ||
a63eaf34 | 4541 | /* |
cdd6c482 | 4542 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4543 | */ |
eb184479 | 4544 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4545 | { |
e625cce1 | 4546 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4547 | mutex_init(&ctx->mutex); |
2fde4f94 | 4548 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4549 | perf_event_groups_init(&ctx->pinned_groups); |
4550 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4551 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4552 | INIT_LIST_HEAD(&ctx->pinned_active); |
4553 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4554 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4555 | } |
4556 | ||
4557 | static struct perf_event_context * | |
4558 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4559 | { | |
4560 | struct perf_event_context *ctx; | |
4561 | ||
4562 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4563 | if (!ctx) | |
4564 | return NULL; | |
4565 | ||
4566 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4567 | if (task) |
4568 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4569 | ctx->pmu = pmu; |
4570 | ||
4571 | return ctx; | |
a63eaf34 PM |
4572 | } |
4573 | ||
2ebd4ffb MH |
4574 | static struct task_struct * |
4575 | find_lively_task_by_vpid(pid_t vpid) | |
4576 | { | |
4577 | struct task_struct *task; | |
0793a61d TG |
4578 | |
4579 | rcu_read_lock(); | |
2ebd4ffb | 4580 | if (!vpid) |
0793a61d TG |
4581 | task = current; |
4582 | else | |
2ebd4ffb | 4583 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4584 | if (task) |
4585 | get_task_struct(task); | |
4586 | rcu_read_unlock(); | |
4587 | ||
4588 | if (!task) | |
4589 | return ERR_PTR(-ESRCH); | |
4590 | ||
2ebd4ffb | 4591 | return task; |
2ebd4ffb MH |
4592 | } |
4593 | ||
fe4b04fa PZ |
4594 | /* |
4595 | * Returns a matching context with refcount and pincount. | |
4596 | */ | |
108b02cf | 4597 | static struct perf_event_context * |
4af57ef2 YZ |
4598 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4599 | struct perf_event *event) | |
0793a61d | 4600 | { |
211de6eb | 4601 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4602 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4603 | void *task_ctx_data = NULL; |
25346b93 | 4604 | unsigned long flags; |
8dc85d54 | 4605 | int ctxn, err; |
4af57ef2 | 4606 | int cpu = event->cpu; |
0793a61d | 4607 | |
22a4ec72 | 4608 | if (!task) { |
cdd6c482 | 4609 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4610 | err = perf_allow_cpu(&event->attr); |
4611 | if (err) | |
4612 | return ERR_PTR(err); | |
0793a61d | 4613 | |
108b02cf | 4614 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4615 | ctx = &cpuctx->ctx; |
c93f7669 | 4616 | get_ctx(ctx); |
fe4b04fa | 4617 | ++ctx->pin_count; |
0793a61d | 4618 | |
0793a61d TG |
4619 | return ctx; |
4620 | } | |
4621 | ||
8dc85d54 PZ |
4622 | err = -EINVAL; |
4623 | ctxn = pmu->task_ctx_nr; | |
4624 | if (ctxn < 0) | |
4625 | goto errout; | |
4626 | ||
4af57ef2 | 4627 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
ff9ff926 | 4628 | task_ctx_data = alloc_task_ctx_data(pmu); |
4af57ef2 YZ |
4629 | if (!task_ctx_data) { |
4630 | err = -ENOMEM; | |
4631 | goto errout; | |
4632 | } | |
4633 | } | |
4634 | ||
9ed6060d | 4635 | retry: |
8dc85d54 | 4636 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4637 | if (ctx) { |
211de6eb | 4638 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4639 | ++ctx->pin_count; |
4af57ef2 YZ |
4640 | |
4641 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4642 | ctx->task_ctx_data = task_ctx_data; | |
4643 | task_ctx_data = NULL; | |
4644 | } | |
e625cce1 | 4645 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4646 | |
4647 | if (clone_ctx) | |
4648 | put_ctx(clone_ctx); | |
9137fb28 | 4649 | } else { |
eb184479 | 4650 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4651 | err = -ENOMEM; |
4652 | if (!ctx) | |
4653 | goto errout; | |
eb184479 | 4654 | |
4af57ef2 YZ |
4655 | if (task_ctx_data) { |
4656 | ctx->task_ctx_data = task_ctx_data; | |
4657 | task_ctx_data = NULL; | |
4658 | } | |
4659 | ||
dbe08d82 ON |
4660 | err = 0; |
4661 | mutex_lock(&task->perf_event_mutex); | |
4662 | /* | |
4663 | * If it has already passed perf_event_exit_task(). | |
4664 | * we must see PF_EXITING, it takes this mutex too. | |
4665 | */ | |
4666 | if (task->flags & PF_EXITING) | |
4667 | err = -ESRCH; | |
4668 | else if (task->perf_event_ctxp[ctxn]) | |
4669 | err = -EAGAIN; | |
fe4b04fa | 4670 | else { |
9137fb28 | 4671 | get_ctx(ctx); |
fe4b04fa | 4672 | ++ctx->pin_count; |
dbe08d82 | 4673 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4674 | } |
dbe08d82 ON |
4675 | mutex_unlock(&task->perf_event_mutex); |
4676 | ||
4677 | if (unlikely(err)) { | |
9137fb28 | 4678 | put_ctx(ctx); |
dbe08d82 ON |
4679 | |
4680 | if (err == -EAGAIN) | |
4681 | goto retry; | |
4682 | goto errout; | |
a63eaf34 PM |
4683 | } |
4684 | } | |
4685 | ||
ff9ff926 | 4686 | free_task_ctx_data(pmu, task_ctx_data); |
0793a61d | 4687 | return ctx; |
c93f7669 | 4688 | |
9ed6060d | 4689 | errout: |
ff9ff926 | 4690 | free_task_ctx_data(pmu, task_ctx_data); |
c93f7669 | 4691 | return ERR_PTR(err); |
0793a61d TG |
4692 | } |
4693 | ||
6fb2915d | 4694 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4695 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4696 | |
cdd6c482 | 4697 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4698 | { |
cdd6c482 | 4699 | struct perf_event *event; |
592903cd | 4700 | |
cdd6c482 IM |
4701 | event = container_of(head, struct perf_event, rcu_head); |
4702 | if (event->ns) | |
4703 | put_pid_ns(event->ns); | |
6fb2915d | 4704 | perf_event_free_filter(event); |
bdacfaf2 | 4705 | kmem_cache_free(perf_event_cache, event); |
592903cd PZ |
4706 | } |
4707 | ||
b69cf536 | 4708 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4709 | struct perf_buffer *rb); |
925d519a | 4710 | |
f2fb6bef KL |
4711 | static void detach_sb_event(struct perf_event *event) |
4712 | { | |
4713 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4714 | ||
4715 | raw_spin_lock(&pel->lock); | |
4716 | list_del_rcu(&event->sb_list); | |
4717 | raw_spin_unlock(&pel->lock); | |
4718 | } | |
4719 | ||
a4f144eb | 4720 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4721 | { |
a4f144eb DCC |
4722 | struct perf_event_attr *attr = &event->attr; |
4723 | ||
f2fb6bef | 4724 | if (event->parent) |
a4f144eb | 4725 | return false; |
f2fb6bef KL |
4726 | |
4727 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4728 | return false; |
f2fb6bef | 4729 | |
a4f144eb DCC |
4730 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4731 | attr->comm || attr->comm_exec || | |
76193a94 | 4732 | attr->task || attr->ksymbol || |
e17d43b9 | 4733 | attr->context_switch || attr->text_poke || |
21038f2b | 4734 | attr->bpf_event) |
a4f144eb DCC |
4735 | return true; |
4736 | return false; | |
4737 | } | |
4738 | ||
4739 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4740 | { | |
4741 | if (is_sb_event(event)) | |
4742 | detach_sb_event(event); | |
f2fb6bef KL |
4743 | } |
4744 | ||
4beb31f3 | 4745 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4746 | { |
4beb31f3 FW |
4747 | if (event->parent) |
4748 | return; | |
4749 | ||
4beb31f3 FW |
4750 | if (is_cgroup_event(event)) |
4751 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4752 | } | |
925d519a | 4753 | |
555e0c1e FW |
4754 | #ifdef CONFIG_NO_HZ_FULL |
4755 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4756 | #endif | |
4757 | ||
4758 | static void unaccount_freq_event_nohz(void) | |
4759 | { | |
4760 | #ifdef CONFIG_NO_HZ_FULL | |
4761 | spin_lock(&nr_freq_lock); | |
4762 | if (atomic_dec_and_test(&nr_freq_events)) | |
4763 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4764 | spin_unlock(&nr_freq_lock); | |
4765 | #endif | |
4766 | } | |
4767 | ||
4768 | static void unaccount_freq_event(void) | |
4769 | { | |
4770 | if (tick_nohz_full_enabled()) | |
4771 | unaccount_freq_event_nohz(); | |
4772 | else | |
4773 | atomic_dec(&nr_freq_events); | |
4774 | } | |
4775 | ||
4beb31f3 FW |
4776 | static void unaccount_event(struct perf_event *event) |
4777 | { | |
25432ae9 PZ |
4778 | bool dec = false; |
4779 | ||
4beb31f3 FW |
4780 | if (event->parent) |
4781 | return; | |
4782 | ||
a5398bff | 4783 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 4784 | dec = true; |
4beb31f3 FW |
4785 | if (event->attr.mmap || event->attr.mmap_data) |
4786 | atomic_dec(&nr_mmap_events); | |
88a16a13 JO |
4787 | if (event->attr.build_id) |
4788 | atomic_dec(&nr_build_id_events); | |
4beb31f3 FW |
4789 | if (event->attr.comm) |
4790 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4791 | if (event->attr.namespaces) |
4792 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4793 | if (event->attr.cgroup) |
4794 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4795 | if (event->attr.task) |
4796 | atomic_dec(&nr_task_events); | |
948b26b6 | 4797 | if (event->attr.freq) |
555e0c1e | 4798 | unaccount_freq_event(); |
45ac1403 | 4799 | if (event->attr.context_switch) { |
25432ae9 | 4800 | dec = true; |
45ac1403 AH |
4801 | atomic_dec(&nr_switch_events); |
4802 | } | |
4beb31f3 | 4803 | if (is_cgroup_event(event)) |
25432ae9 | 4804 | dec = true; |
4beb31f3 | 4805 | if (has_branch_stack(event)) |
25432ae9 | 4806 | dec = true; |
76193a94 SL |
4807 | if (event->attr.ksymbol) |
4808 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4809 | if (event->attr.bpf_event) |
4810 | atomic_dec(&nr_bpf_events); | |
e17d43b9 AH |
4811 | if (event->attr.text_poke) |
4812 | atomic_dec(&nr_text_poke_events); | |
25432ae9 | 4813 | |
9107c89e PZ |
4814 | if (dec) { |
4815 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4816 | schedule_delayed_work(&perf_sched_work, HZ); | |
4817 | } | |
4beb31f3 FW |
4818 | |
4819 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4820 | |
4821 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4822 | } |
925d519a | 4823 | |
9107c89e PZ |
4824 | static void perf_sched_delayed(struct work_struct *work) |
4825 | { | |
4826 | mutex_lock(&perf_sched_mutex); | |
4827 | if (atomic_dec_and_test(&perf_sched_count)) | |
4828 | static_branch_disable(&perf_sched_events); | |
4829 | mutex_unlock(&perf_sched_mutex); | |
4830 | } | |
4831 | ||
bed5b25a AS |
4832 | /* |
4833 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4834 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4835 | * at a time, so we disallow creating events that might conflict, namely: | |
4836 | * | |
4837 | * 1) cpu-wide events in the presence of per-task events, | |
4838 | * 2) per-task events in the presence of cpu-wide events, | |
4839 | * 3) two matching events on the same context. | |
4840 | * | |
4841 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4842 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4843 | */ |
4844 | static int exclusive_event_init(struct perf_event *event) | |
4845 | { | |
4846 | struct pmu *pmu = event->pmu; | |
4847 | ||
8a58ddae | 4848 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4849 | return 0; |
4850 | ||
4851 | /* | |
4852 | * Prevent co-existence of per-task and cpu-wide events on the | |
4853 | * same exclusive pmu. | |
4854 | * | |
4855 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4856 | * events on this "exclusive" pmu, positive means there are | |
4857 | * per-task events. | |
4858 | * | |
4859 | * Since this is called in perf_event_alloc() path, event::ctx | |
4860 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4861 | * to mean "per-task event", because unlike other attach states it | |
4862 | * never gets cleared. | |
4863 | */ | |
4864 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4865 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4866 | return -EBUSY; | |
4867 | } else { | |
4868 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4869 | return -EBUSY; | |
4870 | } | |
4871 | ||
4872 | return 0; | |
4873 | } | |
4874 | ||
4875 | static void exclusive_event_destroy(struct perf_event *event) | |
4876 | { | |
4877 | struct pmu *pmu = event->pmu; | |
4878 | ||
8a58ddae | 4879 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4880 | return; |
4881 | ||
4882 | /* see comment in exclusive_event_init() */ | |
4883 | if (event->attach_state & PERF_ATTACH_TASK) | |
4884 | atomic_dec(&pmu->exclusive_cnt); | |
4885 | else | |
4886 | atomic_inc(&pmu->exclusive_cnt); | |
4887 | } | |
4888 | ||
4889 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4890 | { | |
3bf6215a | 4891 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4892 | (e1->cpu == e2->cpu || |
4893 | e1->cpu == -1 || | |
4894 | e2->cpu == -1)) | |
4895 | return true; | |
4896 | return false; | |
4897 | } | |
4898 | ||
bed5b25a AS |
4899 | static bool exclusive_event_installable(struct perf_event *event, |
4900 | struct perf_event_context *ctx) | |
4901 | { | |
4902 | struct perf_event *iter_event; | |
4903 | struct pmu *pmu = event->pmu; | |
4904 | ||
8a58ddae AS |
4905 | lockdep_assert_held(&ctx->mutex); |
4906 | ||
4907 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4908 | return true; |
4909 | ||
4910 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4911 | if (exclusive_event_match(iter_event, event)) | |
4912 | return false; | |
4913 | } | |
4914 | ||
4915 | return true; | |
4916 | } | |
4917 | ||
375637bc AS |
4918 | static void perf_addr_filters_splice(struct perf_event *event, |
4919 | struct list_head *head); | |
4920 | ||
683ede43 | 4921 | static void _free_event(struct perf_event *event) |
f1600952 | 4922 | { |
e360adbe | 4923 | irq_work_sync(&event->pending); |
925d519a | 4924 | |
4beb31f3 | 4925 | unaccount_event(event); |
9ee318a7 | 4926 | |
da97e184 JFG |
4927 | security_perf_event_free(event); |
4928 | ||
76369139 | 4929 | if (event->rb) { |
9bb5d40c PZ |
4930 | /* |
4931 | * Can happen when we close an event with re-directed output. | |
4932 | * | |
4933 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4934 | * over us; possibly making our ring_buffer_put() the last. | |
4935 | */ | |
4936 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4937 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4938 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4939 | } |
4940 | ||
e5d1367f SE |
4941 | if (is_cgroup_event(event)) |
4942 | perf_detach_cgroup(event); | |
4943 | ||
a0733e69 PZ |
4944 | if (!event->parent) { |
4945 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4946 | put_callchain_buffers(); | |
4947 | } | |
4948 | ||
4949 | perf_event_free_bpf_prog(event); | |
375637bc | 4950 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4951 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4952 | |
4953 | if (event->destroy) | |
4954 | event->destroy(event); | |
4955 | ||
1cf8dfe8 PZ |
4956 | /* |
4957 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4958 | * hw.target. | |
4959 | */ | |
621b6d2e PB |
4960 | if (event->hw.target) |
4961 | put_task_struct(event->hw.target); | |
4962 | ||
1cf8dfe8 PZ |
4963 | /* |
4964 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4965 | * all task references must be cleaned up. | |
4966 | */ | |
4967 | if (event->ctx) | |
4968 | put_ctx(event->ctx); | |
4969 | ||
62a92c8f AS |
4970 | exclusive_event_destroy(event); |
4971 | module_put(event->pmu->module); | |
a0733e69 PZ |
4972 | |
4973 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4974 | } |
4975 | ||
683ede43 PZ |
4976 | /* |
4977 | * Used to free events which have a known refcount of 1, such as in error paths | |
4978 | * where the event isn't exposed yet and inherited events. | |
4979 | */ | |
4980 | static void free_event(struct perf_event *event) | |
0793a61d | 4981 | { |
683ede43 PZ |
4982 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4983 | "unexpected event refcount: %ld; ptr=%p\n", | |
4984 | atomic_long_read(&event->refcount), event)) { | |
4985 | /* leak to avoid use-after-free */ | |
4986 | return; | |
4987 | } | |
0793a61d | 4988 | |
683ede43 | 4989 | _free_event(event); |
0793a61d TG |
4990 | } |
4991 | ||
a66a3052 | 4992 | /* |
f8697762 | 4993 | * Remove user event from the owner task. |
a66a3052 | 4994 | */ |
f8697762 | 4995 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4996 | { |
8882135b | 4997 | struct task_struct *owner; |
fb0459d7 | 4998 | |
8882135b | 4999 | rcu_read_lock(); |
8882135b | 5000 | /* |
f47c02c0 PZ |
5001 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
5002 | * observe !owner it means the list deletion is complete and we can | |
5003 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
5004 | * owner->perf_event_mutex. |
5005 | */ | |
506458ef | 5006 | owner = READ_ONCE(event->owner); |
8882135b PZ |
5007 | if (owner) { |
5008 | /* | |
5009 | * Since delayed_put_task_struct() also drops the last | |
5010 | * task reference we can safely take a new reference | |
5011 | * while holding the rcu_read_lock(). | |
5012 | */ | |
5013 | get_task_struct(owner); | |
5014 | } | |
5015 | rcu_read_unlock(); | |
5016 | ||
5017 | if (owner) { | |
f63a8daa PZ |
5018 | /* |
5019 | * If we're here through perf_event_exit_task() we're already | |
5020 | * holding ctx->mutex which would be an inversion wrt. the | |
5021 | * normal lock order. | |
5022 | * | |
5023 | * However we can safely take this lock because its the child | |
5024 | * ctx->mutex. | |
5025 | */ | |
5026 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
5027 | ||
8882135b PZ |
5028 | /* |
5029 | * We have to re-check the event->owner field, if it is cleared | |
5030 | * we raced with perf_event_exit_task(), acquiring the mutex | |
5031 | * ensured they're done, and we can proceed with freeing the | |
5032 | * event. | |
5033 | */ | |
f47c02c0 | 5034 | if (event->owner) { |
8882135b | 5035 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
5036 | smp_store_release(&event->owner, NULL); |
5037 | } | |
8882135b PZ |
5038 | mutex_unlock(&owner->perf_event_mutex); |
5039 | put_task_struct(owner); | |
5040 | } | |
f8697762 JO |
5041 | } |
5042 | ||
f8697762 JO |
5043 | static void put_event(struct perf_event *event) |
5044 | { | |
f8697762 JO |
5045 | if (!atomic_long_dec_and_test(&event->refcount)) |
5046 | return; | |
5047 | ||
c6e5b732 PZ |
5048 | _free_event(event); |
5049 | } | |
5050 | ||
5051 | /* | |
5052 | * Kill an event dead; while event:refcount will preserve the event | |
5053 | * object, it will not preserve its functionality. Once the last 'user' | |
5054 | * gives up the object, we'll destroy the thing. | |
5055 | */ | |
5056 | int perf_event_release_kernel(struct perf_event *event) | |
5057 | { | |
a4f4bb6d | 5058 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 5059 | struct perf_event *child, *tmp; |
82d94856 | 5060 | LIST_HEAD(free_list); |
c6e5b732 | 5061 | |
a4f4bb6d PZ |
5062 | /* |
5063 | * If we got here through err_file: fput(event_file); we will not have | |
5064 | * attached to a context yet. | |
5065 | */ | |
5066 | if (!ctx) { | |
5067 | WARN_ON_ONCE(event->attach_state & | |
5068 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
5069 | goto no_ctx; | |
5070 | } | |
5071 | ||
f8697762 JO |
5072 | if (!is_kernel_event(event)) |
5073 | perf_remove_from_owner(event); | |
8882135b | 5074 | |
5fa7c8ec | 5075 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 5076 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 5077 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 5078 | |
a69b0ca4 | 5079 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 5080 | /* |
d8a8cfc7 | 5081 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 5082 | * anymore. |
683ede43 | 5083 | * |
a69b0ca4 PZ |
5084 | * Anybody acquiring event->child_mutex after the below loop _must_ |
5085 | * also see this, most importantly inherit_event() which will avoid | |
5086 | * placing more children on the list. | |
683ede43 | 5087 | * |
c6e5b732 PZ |
5088 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
5089 | * child events. | |
683ede43 | 5090 | */ |
a69b0ca4 PZ |
5091 | event->state = PERF_EVENT_STATE_DEAD; |
5092 | raw_spin_unlock_irq(&ctx->lock); | |
5093 | ||
5094 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 5095 | |
c6e5b732 PZ |
5096 | again: |
5097 | mutex_lock(&event->child_mutex); | |
5098 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 5099 | |
c6e5b732 PZ |
5100 | /* |
5101 | * Cannot change, child events are not migrated, see the | |
5102 | * comment with perf_event_ctx_lock_nested(). | |
5103 | */ | |
506458ef | 5104 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
5105 | /* |
5106 | * Since child_mutex nests inside ctx::mutex, we must jump | |
5107 | * through hoops. We start by grabbing a reference on the ctx. | |
5108 | * | |
5109 | * Since the event cannot get freed while we hold the | |
5110 | * child_mutex, the context must also exist and have a !0 | |
5111 | * reference count. | |
5112 | */ | |
5113 | get_ctx(ctx); | |
5114 | ||
5115 | /* | |
5116 | * Now that we have a ctx ref, we can drop child_mutex, and | |
5117 | * acquire ctx::mutex without fear of it going away. Then we | |
5118 | * can re-acquire child_mutex. | |
5119 | */ | |
5120 | mutex_unlock(&event->child_mutex); | |
5121 | mutex_lock(&ctx->mutex); | |
5122 | mutex_lock(&event->child_mutex); | |
5123 | ||
5124 | /* | |
5125 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
5126 | * state, if child is still the first entry, it didn't get freed | |
5127 | * and we can continue doing so. | |
5128 | */ | |
5129 | tmp = list_first_entry_or_null(&event->child_list, | |
5130 | struct perf_event, child_list); | |
5131 | if (tmp == child) { | |
5132 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 5133 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
5134 | /* |
5135 | * This matches the refcount bump in inherit_event(); | |
5136 | * this can't be the last reference. | |
5137 | */ | |
5138 | put_event(event); | |
5139 | } | |
5140 | ||
5141 | mutex_unlock(&event->child_mutex); | |
5142 | mutex_unlock(&ctx->mutex); | |
5143 | put_ctx(ctx); | |
5144 | goto again; | |
5145 | } | |
5146 | mutex_unlock(&event->child_mutex); | |
5147 | ||
82d94856 | 5148 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
5149 | void *var = &child->ctx->refcount; |
5150 | ||
82d94856 PZ |
5151 | list_del(&child->child_list); |
5152 | free_event(child); | |
1cf8dfe8 PZ |
5153 | |
5154 | /* | |
5155 | * Wake any perf_event_free_task() waiting for this event to be | |
5156 | * freed. | |
5157 | */ | |
5158 | smp_mb(); /* pairs with wait_var_event() */ | |
5159 | wake_up_var(var); | |
82d94856 PZ |
5160 | } |
5161 | ||
a4f4bb6d PZ |
5162 | no_ctx: |
5163 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
5164 | return 0; |
5165 | } | |
5166 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
5167 | ||
8b10c5e2 PZ |
5168 | /* |
5169 | * Called when the last reference to the file is gone. | |
5170 | */ | |
a6fa941d AV |
5171 | static int perf_release(struct inode *inode, struct file *file) |
5172 | { | |
c6e5b732 | 5173 | perf_event_release_kernel(file->private_data); |
a6fa941d | 5174 | return 0; |
fb0459d7 | 5175 | } |
fb0459d7 | 5176 | |
ca0dd44c | 5177 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 5178 | { |
cdd6c482 | 5179 | struct perf_event *child; |
e53c0994 PZ |
5180 | u64 total = 0; |
5181 | ||
59ed446f PZ |
5182 | *enabled = 0; |
5183 | *running = 0; | |
5184 | ||
6f10581a | 5185 | mutex_lock(&event->child_mutex); |
01add3ea | 5186 | |
7d88962e | 5187 | (void)perf_event_read(event, false); |
01add3ea SB |
5188 | total += perf_event_count(event); |
5189 | ||
59ed446f PZ |
5190 | *enabled += event->total_time_enabled + |
5191 | atomic64_read(&event->child_total_time_enabled); | |
5192 | *running += event->total_time_running + | |
5193 | atomic64_read(&event->child_total_time_running); | |
5194 | ||
5195 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5196 | (void)perf_event_read(child, false); |
01add3ea | 5197 | total += perf_event_count(child); |
59ed446f PZ |
5198 | *enabled += child->total_time_enabled; |
5199 | *running += child->total_time_running; | |
5200 | } | |
6f10581a | 5201 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5202 | |
5203 | return total; | |
5204 | } | |
ca0dd44c PZ |
5205 | |
5206 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5207 | { | |
5208 | struct perf_event_context *ctx; | |
5209 | u64 count; | |
5210 | ||
5211 | ctx = perf_event_ctx_lock(event); | |
5212 | count = __perf_event_read_value(event, enabled, running); | |
5213 | perf_event_ctx_unlock(event, ctx); | |
5214 | ||
5215 | return count; | |
5216 | } | |
fb0459d7 | 5217 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5218 | |
7d88962e | 5219 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5220 | u64 read_format, u64 *values) |
3dab77fb | 5221 | { |
2aeb1883 | 5222 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5223 | struct perf_event *sub; |
2aeb1883 | 5224 | unsigned long flags; |
fa8c2693 | 5225 | int n = 1; /* skip @nr */ |
7d88962e | 5226 | int ret; |
f63a8daa | 5227 | |
7d88962e SB |
5228 | ret = perf_event_read(leader, true); |
5229 | if (ret) | |
5230 | return ret; | |
abf4868b | 5231 | |
a9cd8194 PZ |
5232 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5233 | ||
fa8c2693 PZ |
5234 | /* |
5235 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5236 | * will be identical to those of the leader, so we only publish one | |
5237 | * set. | |
5238 | */ | |
5239 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5240 | values[n++] += leader->total_time_enabled + | |
5241 | atomic64_read(&leader->child_total_time_enabled); | |
5242 | } | |
3dab77fb | 5243 | |
fa8c2693 PZ |
5244 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5245 | values[n++] += leader->total_time_running + | |
5246 | atomic64_read(&leader->child_total_time_running); | |
5247 | } | |
5248 | ||
5249 | /* | |
5250 | * Write {count,id} tuples for every sibling. | |
5251 | */ | |
5252 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5253 | if (read_format & PERF_FORMAT_ID) |
5254 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5255 | |
edb39592 | 5256 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5257 | values[n++] += perf_event_count(sub); |
5258 | if (read_format & PERF_FORMAT_ID) | |
5259 | values[n++] = primary_event_id(sub); | |
5260 | } | |
7d88962e | 5261 | |
2aeb1883 | 5262 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5263 | return 0; |
fa8c2693 | 5264 | } |
3dab77fb | 5265 | |
fa8c2693 PZ |
5266 | static int perf_read_group(struct perf_event *event, |
5267 | u64 read_format, char __user *buf) | |
5268 | { | |
5269 | struct perf_event *leader = event->group_leader, *child; | |
5270 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5271 | int ret; |
fa8c2693 | 5272 | u64 *values; |
3dab77fb | 5273 | |
fa8c2693 | 5274 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5275 | |
fa8c2693 PZ |
5276 | values = kzalloc(event->read_size, GFP_KERNEL); |
5277 | if (!values) | |
5278 | return -ENOMEM; | |
3dab77fb | 5279 | |
fa8c2693 PZ |
5280 | values[0] = 1 + leader->nr_siblings; |
5281 | ||
5282 | /* | |
5283 | * By locking the child_mutex of the leader we effectively | |
5284 | * lock the child list of all siblings.. XXX explain how. | |
5285 | */ | |
5286 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5287 | |
7d88962e SB |
5288 | ret = __perf_read_group_add(leader, read_format, values); |
5289 | if (ret) | |
5290 | goto unlock; | |
5291 | ||
5292 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5293 | ret = __perf_read_group_add(child, read_format, values); | |
5294 | if (ret) | |
5295 | goto unlock; | |
5296 | } | |
abf4868b | 5297 | |
fa8c2693 | 5298 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5299 | |
7d88962e | 5300 | ret = event->read_size; |
fa8c2693 PZ |
5301 | if (copy_to_user(buf, values, event->read_size)) |
5302 | ret = -EFAULT; | |
7d88962e | 5303 | goto out; |
fa8c2693 | 5304 | |
7d88962e SB |
5305 | unlock: |
5306 | mutex_unlock(&leader->child_mutex); | |
5307 | out: | |
fa8c2693 | 5308 | kfree(values); |
abf4868b | 5309 | return ret; |
3dab77fb PZ |
5310 | } |
5311 | ||
b15f495b | 5312 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5313 | u64 read_format, char __user *buf) |
5314 | { | |
59ed446f | 5315 | u64 enabled, running; |
3dab77fb PZ |
5316 | u64 values[4]; |
5317 | int n = 0; | |
5318 | ||
ca0dd44c | 5319 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5320 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5321 | values[n++] = enabled; | |
5322 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5323 | values[n++] = running; | |
3dab77fb | 5324 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5325 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5326 | |
5327 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5328 | return -EFAULT; | |
5329 | ||
5330 | return n * sizeof(u64); | |
5331 | } | |
5332 | ||
dc633982 JO |
5333 | static bool is_event_hup(struct perf_event *event) |
5334 | { | |
5335 | bool no_children; | |
5336 | ||
a69b0ca4 | 5337 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5338 | return false; |
5339 | ||
5340 | mutex_lock(&event->child_mutex); | |
5341 | no_children = list_empty(&event->child_list); | |
5342 | mutex_unlock(&event->child_mutex); | |
5343 | return no_children; | |
5344 | } | |
5345 | ||
0793a61d | 5346 | /* |
cdd6c482 | 5347 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5348 | */ |
5349 | static ssize_t | |
b15f495b | 5350 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5351 | { |
cdd6c482 | 5352 | u64 read_format = event->attr.read_format; |
3dab77fb | 5353 | int ret; |
0793a61d | 5354 | |
3b6f9e5c | 5355 | /* |
788faab7 | 5356 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5357 | * error state (i.e. because it was pinned but it couldn't be |
5358 | * scheduled on to the CPU at some point). | |
5359 | */ | |
cdd6c482 | 5360 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5361 | return 0; |
5362 | ||
c320c7b7 | 5363 | if (count < event->read_size) |
3dab77fb PZ |
5364 | return -ENOSPC; |
5365 | ||
cdd6c482 | 5366 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5367 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5368 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5369 | else |
b15f495b | 5370 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5371 | |
3dab77fb | 5372 | return ret; |
0793a61d TG |
5373 | } |
5374 | ||
0793a61d TG |
5375 | static ssize_t |
5376 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5377 | { | |
cdd6c482 | 5378 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5379 | struct perf_event_context *ctx; |
5380 | int ret; | |
0793a61d | 5381 | |
da97e184 JFG |
5382 | ret = security_perf_event_read(event); |
5383 | if (ret) | |
5384 | return ret; | |
5385 | ||
f63a8daa | 5386 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5387 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5388 | perf_event_ctx_unlock(event, ctx); |
5389 | ||
5390 | return ret; | |
0793a61d TG |
5391 | } |
5392 | ||
9dd95748 | 5393 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5394 | { |
cdd6c482 | 5395 | struct perf_event *event = file->private_data; |
56de4e8f | 5396 | struct perf_buffer *rb; |
a9a08845 | 5397 | __poll_t events = EPOLLHUP; |
c7138f37 | 5398 | |
e708d7ad | 5399 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5400 | |
dc633982 | 5401 | if (is_event_hup(event)) |
179033b3 | 5402 | return events; |
c7138f37 | 5403 | |
10c6db11 | 5404 | /* |
9bb5d40c PZ |
5405 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5406 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5407 | */ |
5408 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5409 | rb = event->rb; |
5410 | if (rb) | |
76369139 | 5411 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5412 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5413 | return events; |
5414 | } | |
5415 | ||
f63a8daa | 5416 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5417 | { |
7d88962e | 5418 | (void)perf_event_read(event, false); |
e7850595 | 5419 | local64_set(&event->count, 0); |
cdd6c482 | 5420 | perf_event_update_userpage(event); |
3df5edad PZ |
5421 | } |
5422 | ||
52ba4b0b LX |
5423 | /* Assume it's not an event with inherit set. */ |
5424 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5425 | { | |
5426 | struct perf_event_context *ctx; | |
5427 | u64 count; | |
5428 | ||
5429 | ctx = perf_event_ctx_lock(event); | |
5430 | WARN_ON_ONCE(event->attr.inherit); | |
5431 | _perf_event_disable(event); | |
5432 | count = local64_read(&event->count); | |
5433 | if (reset) | |
5434 | local64_set(&event->count, 0); | |
5435 | perf_event_ctx_unlock(event, ctx); | |
5436 | ||
5437 | return count; | |
5438 | } | |
5439 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5440 | ||
c93f7669 | 5441 | /* |
cdd6c482 IM |
5442 | * Holding the top-level event's child_mutex means that any |
5443 | * descendant process that has inherited this event will block | |
8ba289b8 | 5444 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5445 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5446 | */ |
cdd6c482 IM |
5447 | static void perf_event_for_each_child(struct perf_event *event, |
5448 | void (*func)(struct perf_event *)) | |
3df5edad | 5449 | { |
cdd6c482 | 5450 | struct perf_event *child; |
3df5edad | 5451 | |
cdd6c482 | 5452 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5453 | |
cdd6c482 IM |
5454 | mutex_lock(&event->child_mutex); |
5455 | func(event); | |
5456 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5457 | func(child); |
cdd6c482 | 5458 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5459 | } |
5460 | ||
cdd6c482 IM |
5461 | static void perf_event_for_each(struct perf_event *event, |
5462 | void (*func)(struct perf_event *)) | |
3df5edad | 5463 | { |
cdd6c482 IM |
5464 | struct perf_event_context *ctx = event->ctx; |
5465 | struct perf_event *sibling; | |
3df5edad | 5466 | |
f63a8daa PZ |
5467 | lockdep_assert_held(&ctx->mutex); |
5468 | ||
cdd6c482 | 5469 | event = event->group_leader; |
75f937f2 | 5470 | |
cdd6c482 | 5471 | perf_event_for_each_child(event, func); |
edb39592 | 5472 | for_each_sibling_event(sibling, event) |
724b6daa | 5473 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5474 | } |
5475 | ||
fae3fde6 PZ |
5476 | static void __perf_event_period(struct perf_event *event, |
5477 | struct perf_cpu_context *cpuctx, | |
5478 | struct perf_event_context *ctx, | |
5479 | void *info) | |
c7999c6f | 5480 | { |
fae3fde6 | 5481 | u64 value = *((u64 *)info); |
c7999c6f | 5482 | bool active; |
08247e31 | 5483 | |
cdd6c482 | 5484 | if (event->attr.freq) { |
cdd6c482 | 5485 | event->attr.sample_freq = value; |
08247e31 | 5486 | } else { |
cdd6c482 IM |
5487 | event->attr.sample_period = value; |
5488 | event->hw.sample_period = value; | |
08247e31 | 5489 | } |
bad7192b PZ |
5490 | |
5491 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5492 | if (active) { | |
5493 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5494 | /* |
5495 | * We could be throttled; unthrottle now to avoid the tick | |
5496 | * trying to unthrottle while we already re-started the event. | |
5497 | */ | |
5498 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5499 | event->hw.interrupts = 0; | |
5500 | perf_log_throttle(event, 1); | |
5501 | } | |
bad7192b PZ |
5502 | event->pmu->stop(event, PERF_EF_UPDATE); |
5503 | } | |
5504 | ||
5505 | local64_set(&event->hw.period_left, 0); | |
5506 | ||
5507 | if (active) { | |
5508 | event->pmu->start(event, PERF_EF_RELOAD); | |
5509 | perf_pmu_enable(ctx->pmu); | |
5510 | } | |
c7999c6f PZ |
5511 | } |
5512 | ||
81ec3f3c JO |
5513 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5514 | { | |
5515 | return event->pmu->check_period(event, value); | |
5516 | } | |
5517 | ||
3ca270fc | 5518 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5519 | { |
c7999c6f PZ |
5520 | if (!is_sampling_event(event)) |
5521 | return -EINVAL; | |
5522 | ||
c7999c6f PZ |
5523 | if (!value) |
5524 | return -EINVAL; | |
5525 | ||
5526 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5527 | return -EINVAL; | |
5528 | ||
81ec3f3c JO |
5529 | if (perf_event_check_period(event, value)) |
5530 | return -EINVAL; | |
5531 | ||
913a90bc RB |
5532 | if (!event->attr.freq && (value & (1ULL << 63))) |
5533 | return -EINVAL; | |
5534 | ||
fae3fde6 | 5535 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5536 | |
c7999c6f | 5537 | return 0; |
08247e31 PZ |
5538 | } |
5539 | ||
3ca270fc LX |
5540 | int perf_event_period(struct perf_event *event, u64 value) |
5541 | { | |
5542 | struct perf_event_context *ctx; | |
5543 | int ret; | |
5544 | ||
5545 | ctx = perf_event_ctx_lock(event); | |
5546 | ret = _perf_event_period(event, value); | |
5547 | perf_event_ctx_unlock(event, ctx); | |
5548 | ||
5549 | return ret; | |
5550 | } | |
5551 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5552 | ||
ac9721f3 PZ |
5553 | static const struct file_operations perf_fops; |
5554 | ||
2903ff01 | 5555 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5556 | { |
2903ff01 AV |
5557 | struct fd f = fdget(fd); |
5558 | if (!f.file) | |
5559 | return -EBADF; | |
ac9721f3 | 5560 | |
2903ff01 AV |
5561 | if (f.file->f_op != &perf_fops) { |
5562 | fdput(f); | |
5563 | return -EBADF; | |
ac9721f3 | 5564 | } |
2903ff01 AV |
5565 | *p = f; |
5566 | return 0; | |
ac9721f3 PZ |
5567 | } |
5568 | ||
5569 | static int perf_event_set_output(struct perf_event *event, | |
5570 | struct perf_event *output_event); | |
6fb2915d | 5571 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5572 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5573 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5574 | struct perf_event_attr *attr); | |
a4be7c27 | 5575 | |
f63a8daa | 5576 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5577 | { |
cdd6c482 | 5578 | void (*func)(struct perf_event *); |
3df5edad | 5579 | u32 flags = arg; |
d859e29f PM |
5580 | |
5581 | switch (cmd) { | |
cdd6c482 | 5582 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5583 | func = _perf_event_enable; |
d859e29f | 5584 | break; |
cdd6c482 | 5585 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5586 | func = _perf_event_disable; |
79f14641 | 5587 | break; |
cdd6c482 | 5588 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5589 | func = _perf_event_reset; |
6de6a7b9 | 5590 | break; |
3df5edad | 5591 | |
cdd6c482 | 5592 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5593 | return _perf_event_refresh(event, arg); |
08247e31 | 5594 | |
cdd6c482 | 5595 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5596 | { |
5597 | u64 value; | |
08247e31 | 5598 | |
3ca270fc LX |
5599 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5600 | return -EFAULT; | |
08247e31 | 5601 | |
3ca270fc LX |
5602 | return _perf_event_period(event, value); |
5603 | } | |
cf4957f1 JO |
5604 | case PERF_EVENT_IOC_ID: |
5605 | { | |
5606 | u64 id = primary_event_id(event); | |
5607 | ||
5608 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5609 | return -EFAULT; | |
5610 | return 0; | |
5611 | } | |
5612 | ||
cdd6c482 | 5613 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5614 | { |
ac9721f3 | 5615 | int ret; |
ac9721f3 | 5616 | if (arg != -1) { |
2903ff01 AV |
5617 | struct perf_event *output_event; |
5618 | struct fd output; | |
5619 | ret = perf_fget_light(arg, &output); | |
5620 | if (ret) | |
5621 | return ret; | |
5622 | output_event = output.file->private_data; | |
5623 | ret = perf_event_set_output(event, output_event); | |
5624 | fdput(output); | |
5625 | } else { | |
5626 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5627 | } |
ac9721f3 PZ |
5628 | return ret; |
5629 | } | |
a4be7c27 | 5630 | |
6fb2915d LZ |
5631 | case PERF_EVENT_IOC_SET_FILTER: |
5632 | return perf_event_set_filter(event, (void __user *)arg); | |
5633 | ||
2541517c AS |
5634 | case PERF_EVENT_IOC_SET_BPF: |
5635 | return perf_event_set_bpf_prog(event, arg); | |
5636 | ||
86e7972f | 5637 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5638 | struct perf_buffer *rb; |
86e7972f WN |
5639 | |
5640 | rcu_read_lock(); | |
5641 | rb = rcu_dereference(event->rb); | |
5642 | if (!rb || !rb->nr_pages) { | |
5643 | rcu_read_unlock(); | |
5644 | return -EINVAL; | |
5645 | } | |
5646 | rb_toggle_paused(rb, !!arg); | |
5647 | rcu_read_unlock(); | |
5648 | return 0; | |
5649 | } | |
f371b304 YS |
5650 | |
5651 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5652 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5653 | |
5654 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5655 | struct perf_event_attr new_attr; | |
5656 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5657 | &new_attr); | |
5658 | ||
5659 | if (err) | |
5660 | return err; | |
5661 | ||
5662 | return perf_event_modify_attr(event, &new_attr); | |
5663 | } | |
d859e29f | 5664 | default: |
3df5edad | 5665 | return -ENOTTY; |
d859e29f | 5666 | } |
3df5edad PZ |
5667 | |
5668 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5669 | perf_event_for_each(event, func); |
3df5edad | 5670 | else |
cdd6c482 | 5671 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5672 | |
5673 | return 0; | |
d859e29f PM |
5674 | } |
5675 | ||
f63a8daa PZ |
5676 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5677 | { | |
5678 | struct perf_event *event = file->private_data; | |
5679 | struct perf_event_context *ctx; | |
5680 | long ret; | |
5681 | ||
da97e184 JFG |
5682 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5683 | ret = security_perf_event_write(event); | |
5684 | if (ret) | |
5685 | return ret; | |
5686 | ||
f63a8daa PZ |
5687 | ctx = perf_event_ctx_lock(event); |
5688 | ret = _perf_ioctl(event, cmd, arg); | |
5689 | perf_event_ctx_unlock(event, ctx); | |
5690 | ||
5691 | return ret; | |
5692 | } | |
5693 | ||
b3f20785 PM |
5694 | #ifdef CONFIG_COMPAT |
5695 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5696 | unsigned long arg) | |
5697 | { | |
5698 | switch (_IOC_NR(cmd)) { | |
5699 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5700 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5701 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5702 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5703 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5704 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5705 | cmd &= ~IOCSIZE_MASK; | |
5706 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5707 | } | |
5708 | break; | |
5709 | } | |
5710 | return perf_ioctl(file, cmd, arg); | |
5711 | } | |
5712 | #else | |
5713 | # define perf_compat_ioctl NULL | |
5714 | #endif | |
5715 | ||
cdd6c482 | 5716 | int perf_event_task_enable(void) |
771d7cde | 5717 | { |
f63a8daa | 5718 | struct perf_event_context *ctx; |
cdd6c482 | 5719 | struct perf_event *event; |
771d7cde | 5720 | |
cdd6c482 | 5721 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5722 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5723 | ctx = perf_event_ctx_lock(event); | |
5724 | perf_event_for_each_child(event, _perf_event_enable); | |
5725 | perf_event_ctx_unlock(event, ctx); | |
5726 | } | |
cdd6c482 | 5727 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5728 | |
5729 | return 0; | |
5730 | } | |
5731 | ||
cdd6c482 | 5732 | int perf_event_task_disable(void) |
771d7cde | 5733 | { |
f63a8daa | 5734 | struct perf_event_context *ctx; |
cdd6c482 | 5735 | struct perf_event *event; |
771d7cde | 5736 | |
cdd6c482 | 5737 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5738 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5739 | ctx = perf_event_ctx_lock(event); | |
5740 | perf_event_for_each_child(event, _perf_event_disable); | |
5741 | perf_event_ctx_unlock(event, ctx); | |
5742 | } | |
cdd6c482 | 5743 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5744 | |
5745 | return 0; | |
5746 | } | |
5747 | ||
cdd6c482 | 5748 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5749 | { |
a4eaf7f1 PZ |
5750 | if (event->hw.state & PERF_HES_STOPPED) |
5751 | return 0; | |
5752 | ||
cdd6c482 | 5753 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5754 | return 0; |
5755 | ||
35edc2a5 | 5756 | return event->pmu->event_idx(event); |
194002b2 PZ |
5757 | } |
5758 | ||
c4794295 | 5759 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5760 | u64 *now, |
7f310a5d EM |
5761 | u64 *enabled, |
5762 | u64 *running) | |
c4794295 | 5763 | { |
e3f3541c | 5764 | u64 ctx_time; |
c4794295 | 5765 | |
e3f3541c PZ |
5766 | *now = perf_clock(); |
5767 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5768 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5769 | } |
5770 | ||
fa731587 PZ |
5771 | static void perf_event_init_userpage(struct perf_event *event) |
5772 | { | |
5773 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5774 | struct perf_buffer *rb; |
fa731587 PZ |
5775 | |
5776 | rcu_read_lock(); | |
5777 | rb = rcu_dereference(event->rb); | |
5778 | if (!rb) | |
5779 | goto unlock; | |
5780 | ||
5781 | userpg = rb->user_page; | |
5782 | ||
5783 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5784 | userpg->cap_bit0_is_deprecated = 1; | |
5785 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5786 | userpg->data_offset = PAGE_SIZE; |
5787 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5788 | |
5789 | unlock: | |
5790 | rcu_read_unlock(); | |
5791 | } | |
5792 | ||
c1317ec2 AL |
5793 | void __weak arch_perf_update_userpage( |
5794 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5795 | { |
5796 | } | |
5797 | ||
38ff667b PZ |
5798 | /* |
5799 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5800 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5801 | * code calls this from NMI context. | |
5802 | */ | |
cdd6c482 | 5803 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5804 | { |
cdd6c482 | 5805 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5806 | struct perf_buffer *rb; |
e3f3541c | 5807 | u64 enabled, running, now; |
38ff667b PZ |
5808 | |
5809 | rcu_read_lock(); | |
5ec4c599 PZ |
5810 | rb = rcu_dereference(event->rb); |
5811 | if (!rb) | |
5812 | goto unlock; | |
5813 | ||
0d641208 EM |
5814 | /* |
5815 | * compute total_time_enabled, total_time_running | |
5816 | * based on snapshot values taken when the event | |
5817 | * was last scheduled in. | |
5818 | * | |
5819 | * we cannot simply called update_context_time() | |
5820 | * because of locking issue as we can be called in | |
5821 | * NMI context | |
5822 | */ | |
e3f3541c | 5823 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5824 | |
76369139 | 5825 | userpg = rb->user_page; |
7b732a75 | 5826 | /* |
9d2dcc8f MF |
5827 | * Disable preemption to guarantee consistent time stamps are stored to |
5828 | * the user page. | |
7b732a75 PZ |
5829 | */ |
5830 | preempt_disable(); | |
37d81828 | 5831 | ++userpg->lock; |
92f22a38 | 5832 | barrier(); |
cdd6c482 | 5833 | userpg->index = perf_event_index(event); |
b5e58793 | 5834 | userpg->offset = perf_event_count(event); |
365a4038 | 5835 | if (userpg->index) |
e7850595 | 5836 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5837 | |
0d641208 | 5838 | userpg->time_enabled = enabled + |
cdd6c482 | 5839 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5840 | |
0d641208 | 5841 | userpg->time_running = running + |
cdd6c482 | 5842 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5843 | |
c1317ec2 | 5844 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5845 | |
92f22a38 | 5846 | barrier(); |
37d81828 | 5847 | ++userpg->lock; |
7b732a75 | 5848 | preempt_enable(); |
38ff667b | 5849 | unlock: |
7b732a75 | 5850 | rcu_read_unlock(); |
37d81828 | 5851 | } |
82975c46 | 5852 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5853 | |
9e3ed2d7 | 5854 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5855 | { |
11bac800 | 5856 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5857 | struct perf_buffer *rb; |
9e3ed2d7 | 5858 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5859 | |
5860 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5861 | if (vmf->pgoff == 0) | |
5862 | ret = 0; | |
5863 | return ret; | |
5864 | } | |
5865 | ||
5866 | rcu_read_lock(); | |
76369139 FW |
5867 | rb = rcu_dereference(event->rb); |
5868 | if (!rb) | |
906010b2 PZ |
5869 | goto unlock; |
5870 | ||
5871 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5872 | goto unlock; | |
5873 | ||
76369139 | 5874 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5875 | if (!vmf->page) |
5876 | goto unlock; | |
5877 | ||
5878 | get_page(vmf->page); | |
11bac800 | 5879 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5880 | vmf->page->index = vmf->pgoff; |
5881 | ||
5882 | ret = 0; | |
5883 | unlock: | |
5884 | rcu_read_unlock(); | |
5885 | ||
5886 | return ret; | |
5887 | } | |
5888 | ||
10c6db11 | 5889 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5890 | struct perf_buffer *rb) |
10c6db11 | 5891 | { |
56de4e8f | 5892 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5893 | unsigned long flags; |
5894 | ||
b69cf536 PZ |
5895 | if (event->rb) { |
5896 | /* | |
5897 | * Should be impossible, we set this when removing | |
5898 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5899 | */ | |
5900 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5901 | |
b69cf536 | 5902 | old_rb = event->rb; |
b69cf536 PZ |
5903 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5904 | list_del_rcu(&event->rb_entry); | |
5905 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5906 | |
2f993cf0 ON |
5907 | event->rcu_batches = get_state_synchronize_rcu(); |
5908 | event->rcu_pending = 1; | |
b69cf536 | 5909 | } |
10c6db11 | 5910 | |
b69cf536 | 5911 | if (rb) { |
2f993cf0 ON |
5912 | if (event->rcu_pending) { |
5913 | cond_synchronize_rcu(event->rcu_batches); | |
5914 | event->rcu_pending = 0; | |
5915 | } | |
5916 | ||
b69cf536 PZ |
5917 | spin_lock_irqsave(&rb->event_lock, flags); |
5918 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5919 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5920 | } | |
5921 | ||
767ae086 AS |
5922 | /* |
5923 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5924 | * before swizzling the event::rb pointer; if it's getting | |
5925 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5926 | * restart. See the comment in __perf_pmu_output_stop(). | |
5927 | * | |
5928 | * Data will inevitably be lost when set_output is done in | |
5929 | * mid-air, but then again, whoever does it like this is | |
5930 | * not in for the data anyway. | |
5931 | */ | |
5932 | if (has_aux(event)) | |
5933 | perf_event_stop(event, 0); | |
5934 | ||
b69cf536 PZ |
5935 | rcu_assign_pointer(event->rb, rb); |
5936 | ||
5937 | if (old_rb) { | |
5938 | ring_buffer_put(old_rb); | |
5939 | /* | |
5940 | * Since we detached before setting the new rb, so that we | |
5941 | * could attach the new rb, we could have missed a wakeup. | |
5942 | * Provide it now. | |
5943 | */ | |
5944 | wake_up_all(&event->waitq); | |
5945 | } | |
10c6db11 PZ |
5946 | } |
5947 | ||
5948 | static void ring_buffer_wakeup(struct perf_event *event) | |
5949 | { | |
56de4e8f | 5950 | struct perf_buffer *rb; |
10c6db11 PZ |
5951 | |
5952 | rcu_read_lock(); | |
5953 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5954 | if (rb) { |
5955 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5956 | wake_up_all(&event->waitq); | |
5957 | } | |
10c6db11 PZ |
5958 | rcu_read_unlock(); |
5959 | } | |
5960 | ||
56de4e8f | 5961 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5962 | { |
56de4e8f | 5963 | struct perf_buffer *rb; |
7b732a75 | 5964 | |
ac9721f3 | 5965 | rcu_read_lock(); |
76369139 FW |
5966 | rb = rcu_dereference(event->rb); |
5967 | if (rb) { | |
fecb8ed2 | 5968 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5969 | rb = NULL; |
ac9721f3 PZ |
5970 | } |
5971 | rcu_read_unlock(); | |
5972 | ||
76369139 | 5973 | return rb; |
ac9721f3 PZ |
5974 | } |
5975 | ||
56de4e8f | 5976 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5977 | { |
fecb8ed2 | 5978 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5979 | return; |
7b732a75 | 5980 | |
9bb5d40c | 5981 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5982 | |
76369139 | 5983 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5984 | } |
5985 | ||
5986 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5987 | { | |
cdd6c482 | 5988 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5989 | |
cdd6c482 | 5990 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5991 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5992 | |
45bfb2e5 PZ |
5993 | if (vma->vm_pgoff) |
5994 | atomic_inc(&event->rb->aux_mmap_count); | |
5995 | ||
1e0fb9ec | 5996 | if (event->pmu->event_mapped) |
bfe33492 | 5997 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5998 | } |
5999 | ||
95ff4ca2 AS |
6000 | static void perf_pmu_output_stop(struct perf_event *event); |
6001 | ||
9bb5d40c PZ |
6002 | /* |
6003 | * A buffer can be mmap()ed multiple times; either directly through the same | |
6004 | * event, or through other events by use of perf_event_set_output(). | |
6005 | * | |
6006 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
6007 | * the buffer here, where we still have a VM context. This means we need | |
6008 | * to detach all events redirecting to us. | |
6009 | */ | |
7b732a75 PZ |
6010 | static void perf_mmap_close(struct vm_area_struct *vma) |
6011 | { | |
cdd6c482 | 6012 | struct perf_event *event = vma->vm_file->private_data; |
56de4e8f | 6013 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
6014 | struct user_struct *mmap_user = rb->mmap_user; |
6015 | int mmap_locked = rb->mmap_locked; | |
6016 | unsigned long size = perf_data_size(rb); | |
f91072ed | 6017 | bool detach_rest = false; |
789f90fc | 6018 | |
1e0fb9ec | 6019 | if (event->pmu->event_unmapped) |
bfe33492 | 6020 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 6021 | |
45bfb2e5 PZ |
6022 | /* |
6023 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
6024 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
6025 | * serialize with perf_mmap here. | |
6026 | */ | |
6027 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
6028 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
6029 | /* |
6030 | * Stop all AUX events that are writing to this buffer, | |
6031 | * so that we can free its AUX pages and corresponding PMU | |
6032 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
6033 | * they won't start any more (see perf_aux_output_begin()). | |
6034 | */ | |
6035 | perf_pmu_output_stop(event); | |
6036 | ||
6037 | /* now it's safe to free the pages */ | |
36b3db03 AS |
6038 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
6039 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 6040 | |
95ff4ca2 | 6041 | /* this has to be the last one */ |
45bfb2e5 | 6042 | rb_free_aux(rb); |
ca3bb3d0 | 6043 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 6044 | |
45bfb2e5 PZ |
6045 | mutex_unlock(&event->mmap_mutex); |
6046 | } | |
6047 | ||
f91072ed JO |
6048 | if (atomic_dec_and_test(&rb->mmap_count)) |
6049 | detach_rest = true; | |
9bb5d40c PZ |
6050 | |
6051 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 6052 | goto out_put; |
9bb5d40c | 6053 | |
b69cf536 | 6054 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
6055 | mutex_unlock(&event->mmap_mutex); |
6056 | ||
6057 | /* If there's still other mmap()s of this buffer, we're done. */ | |
f91072ed | 6058 | if (!detach_rest) |
b69cf536 | 6059 | goto out_put; |
ac9721f3 | 6060 | |
9bb5d40c PZ |
6061 | /* |
6062 | * No other mmap()s, detach from all other events that might redirect | |
6063 | * into the now unreachable buffer. Somewhat complicated by the | |
6064 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
6065 | */ | |
6066 | again: | |
6067 | rcu_read_lock(); | |
6068 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
6069 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
6070 | /* | |
6071 | * This event is en-route to free_event() which will | |
6072 | * detach it and remove it from the list. | |
6073 | */ | |
6074 | continue; | |
6075 | } | |
6076 | rcu_read_unlock(); | |
789f90fc | 6077 | |
9bb5d40c PZ |
6078 | mutex_lock(&event->mmap_mutex); |
6079 | /* | |
6080 | * Check we didn't race with perf_event_set_output() which can | |
6081 | * swizzle the rb from under us while we were waiting to | |
6082 | * acquire mmap_mutex. | |
6083 | * | |
6084 | * If we find a different rb; ignore this event, a next | |
6085 | * iteration will no longer find it on the list. We have to | |
6086 | * still restart the iteration to make sure we're not now | |
6087 | * iterating the wrong list. | |
6088 | */ | |
b69cf536 PZ |
6089 | if (event->rb == rb) |
6090 | ring_buffer_attach(event, NULL); | |
6091 | ||
cdd6c482 | 6092 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 6093 | put_event(event); |
ac9721f3 | 6094 | |
9bb5d40c PZ |
6095 | /* |
6096 | * Restart the iteration; either we're on the wrong list or | |
6097 | * destroyed its integrity by doing a deletion. | |
6098 | */ | |
6099 | goto again; | |
7b732a75 | 6100 | } |
9bb5d40c PZ |
6101 | rcu_read_unlock(); |
6102 | ||
6103 | /* | |
6104 | * It could be there's still a few 0-ref events on the list; they'll | |
6105 | * get cleaned up by free_event() -- they'll also still have their | |
6106 | * ref on the rb and will free it whenever they are done with it. | |
6107 | * | |
6108 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
6109 | * undo the VM accounting. | |
6110 | */ | |
6111 | ||
d44248a4 SL |
6112 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
6113 | &mmap_user->locked_vm); | |
70f8a3ca | 6114 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
6115 | free_uid(mmap_user); |
6116 | ||
b69cf536 | 6117 | out_put: |
9bb5d40c | 6118 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
6119 | } |
6120 | ||
f0f37e2f | 6121 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 6122 | .open = perf_mmap_open, |
fca0c116 | 6123 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
6124 | .fault = perf_mmap_fault, |
6125 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
6126 | }; |
6127 | ||
6128 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
6129 | { | |
cdd6c482 | 6130 | struct perf_event *event = file->private_data; |
22a4f650 | 6131 | unsigned long user_locked, user_lock_limit; |
789f90fc | 6132 | struct user_struct *user = current_user(); |
56de4e8f | 6133 | struct perf_buffer *rb = NULL; |
22a4f650 | 6134 | unsigned long locked, lock_limit; |
7b732a75 PZ |
6135 | unsigned long vma_size; |
6136 | unsigned long nr_pages; | |
45bfb2e5 | 6137 | long user_extra = 0, extra = 0; |
d57e34fd | 6138 | int ret = 0, flags = 0; |
37d81828 | 6139 | |
c7920614 PZ |
6140 | /* |
6141 | * Don't allow mmap() of inherited per-task counters. This would | |
6142 | * create a performance issue due to all children writing to the | |
76369139 | 6143 | * same rb. |
c7920614 PZ |
6144 | */ |
6145 | if (event->cpu == -1 && event->attr.inherit) | |
6146 | return -EINVAL; | |
6147 | ||
43a21ea8 | 6148 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 6149 | return -EINVAL; |
7b732a75 | 6150 | |
da97e184 JFG |
6151 | ret = security_perf_event_read(event); |
6152 | if (ret) | |
6153 | return ret; | |
6154 | ||
7b732a75 | 6155 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
6156 | |
6157 | if (vma->vm_pgoff == 0) { | |
6158 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
6159 | } else { | |
6160 | /* | |
6161 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
6162 | * mapped, all subsequent mappings should have the same size | |
6163 | * and offset. Must be above the normal perf buffer. | |
6164 | */ | |
6165 | u64 aux_offset, aux_size; | |
6166 | ||
6167 | if (!event->rb) | |
6168 | return -EINVAL; | |
6169 | ||
6170 | nr_pages = vma_size / PAGE_SIZE; | |
6171 | ||
6172 | mutex_lock(&event->mmap_mutex); | |
6173 | ret = -EINVAL; | |
6174 | ||
6175 | rb = event->rb; | |
6176 | if (!rb) | |
6177 | goto aux_unlock; | |
6178 | ||
6aa7de05 MR |
6179 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
6180 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6181 | |
6182 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6183 | goto aux_unlock; | |
6184 | ||
6185 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6186 | goto aux_unlock; | |
6187 | ||
6188 | /* already mapped with a different offset */ | |
6189 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6190 | goto aux_unlock; | |
6191 | ||
6192 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6193 | goto aux_unlock; | |
6194 | ||
6195 | /* already mapped with a different size */ | |
6196 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6197 | goto aux_unlock; | |
6198 | ||
6199 | if (!is_power_of_2(nr_pages)) | |
6200 | goto aux_unlock; | |
6201 | ||
6202 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6203 | goto aux_unlock; | |
6204 | ||
6205 | if (rb_has_aux(rb)) { | |
6206 | atomic_inc(&rb->aux_mmap_count); | |
6207 | ret = 0; | |
6208 | goto unlock; | |
6209 | } | |
6210 | ||
6211 | atomic_set(&rb->aux_mmap_count, 1); | |
6212 | user_extra = nr_pages; | |
6213 | ||
6214 | goto accounting; | |
6215 | } | |
7b732a75 | 6216 | |
7730d865 | 6217 | /* |
76369139 | 6218 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6219 | * can do bitmasks instead of modulo. |
6220 | */ | |
2ed11312 | 6221 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6222 | return -EINVAL; |
6223 | ||
7b732a75 | 6224 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6225 | return -EINVAL; |
6226 | ||
cdd6c482 | 6227 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6228 | again: |
cdd6c482 | 6229 | mutex_lock(&event->mmap_mutex); |
76369139 | 6230 | if (event->rb) { |
9bb5d40c | 6231 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6232 | ret = -EINVAL; |
9bb5d40c PZ |
6233 | goto unlock; |
6234 | } | |
6235 | ||
6236 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6237 | /* | |
6238 | * Raced against perf_mmap_close() through | |
6239 | * perf_event_set_output(). Try again, hope for better | |
6240 | * luck. | |
6241 | */ | |
6242 | mutex_unlock(&event->mmap_mutex); | |
6243 | goto again; | |
6244 | } | |
6245 | ||
ebb3c4c4 PZ |
6246 | goto unlock; |
6247 | } | |
6248 | ||
789f90fc | 6249 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6250 | |
6251 | accounting: | |
cdd6c482 | 6252 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6253 | |
6254 | /* | |
6255 | * Increase the limit linearly with more CPUs: | |
6256 | */ | |
6257 | user_lock_limit *= num_online_cpus(); | |
6258 | ||
00346155 SL |
6259 | user_locked = atomic_long_read(&user->locked_vm); |
6260 | ||
6261 | /* | |
6262 | * sysctl_perf_event_mlock may have changed, so that | |
6263 | * user->locked_vm > user_lock_limit | |
6264 | */ | |
6265 | if (user_locked > user_lock_limit) | |
6266 | user_locked = user_lock_limit; | |
6267 | user_locked += user_extra; | |
c5078f78 | 6268 | |
c4b75479 | 6269 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6270 | /* |
6271 | * charge locked_vm until it hits user_lock_limit; | |
6272 | * charge the rest from pinned_vm | |
6273 | */ | |
789f90fc | 6274 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6275 | user_extra -= extra; |
6276 | } | |
7b732a75 | 6277 | |
78d7d407 | 6278 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6279 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6280 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6281 | |
da97e184 | 6282 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6283 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6284 | ret = -EPERM; |
6285 | goto unlock; | |
6286 | } | |
7b732a75 | 6287 | |
45bfb2e5 | 6288 | WARN_ON(!rb && event->rb); |
906010b2 | 6289 | |
d57e34fd | 6290 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6291 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6292 | |
76369139 | 6293 | if (!rb) { |
45bfb2e5 PZ |
6294 | rb = rb_alloc(nr_pages, |
6295 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6296 | event->cpu, flags); | |
26cb63ad | 6297 | |
45bfb2e5 PZ |
6298 | if (!rb) { |
6299 | ret = -ENOMEM; | |
6300 | goto unlock; | |
6301 | } | |
43a21ea8 | 6302 | |
45bfb2e5 PZ |
6303 | atomic_set(&rb->mmap_count, 1); |
6304 | rb->mmap_user = get_current_user(); | |
6305 | rb->mmap_locked = extra; | |
26cb63ad | 6306 | |
45bfb2e5 | 6307 | ring_buffer_attach(event, rb); |
ac9721f3 | 6308 | |
45bfb2e5 PZ |
6309 | perf_event_init_userpage(event); |
6310 | perf_event_update_userpage(event); | |
6311 | } else { | |
1a594131 AS |
6312 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6313 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6314 | if (!ret) |
6315 | rb->aux_mmap_locked = extra; | |
6316 | } | |
9a0f05cb | 6317 | |
ebb3c4c4 | 6318 | unlock: |
45bfb2e5 PZ |
6319 | if (!ret) { |
6320 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6321 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6322 | |
ac9721f3 | 6323 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6324 | } else if (rb) { |
6325 | atomic_dec(&rb->mmap_count); | |
6326 | } | |
6327 | aux_unlock: | |
cdd6c482 | 6328 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6329 | |
9bb5d40c PZ |
6330 | /* |
6331 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6332 | * vma. | |
6333 | */ | |
26cb63ad | 6334 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6335 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6336 | |
1e0fb9ec | 6337 | if (event->pmu->event_mapped) |
bfe33492 | 6338 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6339 | |
7b732a75 | 6340 | return ret; |
37d81828 PM |
6341 | } |
6342 | ||
3c446b3d PZ |
6343 | static int perf_fasync(int fd, struct file *filp, int on) |
6344 | { | |
496ad9aa | 6345 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6346 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6347 | int retval; |
6348 | ||
5955102c | 6349 | inode_lock(inode); |
cdd6c482 | 6350 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6351 | inode_unlock(inode); |
3c446b3d PZ |
6352 | |
6353 | if (retval < 0) | |
6354 | return retval; | |
6355 | ||
6356 | return 0; | |
6357 | } | |
6358 | ||
0793a61d | 6359 | static const struct file_operations perf_fops = { |
3326c1ce | 6360 | .llseek = no_llseek, |
0793a61d TG |
6361 | .release = perf_release, |
6362 | .read = perf_read, | |
6363 | .poll = perf_poll, | |
d859e29f | 6364 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6365 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6366 | .mmap = perf_mmap, |
3c446b3d | 6367 | .fasync = perf_fasync, |
0793a61d TG |
6368 | }; |
6369 | ||
925d519a | 6370 | /* |
cdd6c482 | 6371 | * Perf event wakeup |
925d519a PZ |
6372 | * |
6373 | * If there's data, ensure we set the poll() state and publish everything | |
6374 | * to user-space before waking everybody up. | |
6375 | */ | |
6376 | ||
fed66e2c PZ |
6377 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6378 | { | |
6379 | /* only the parent has fasync state */ | |
6380 | if (event->parent) | |
6381 | event = event->parent; | |
6382 | return &event->fasync; | |
6383 | } | |
6384 | ||
cdd6c482 | 6385 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6386 | { |
10c6db11 | 6387 | ring_buffer_wakeup(event); |
4c9e2542 | 6388 | |
cdd6c482 | 6389 | if (event->pending_kill) { |
fed66e2c | 6390 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6391 | event->pending_kill = 0; |
4c9e2542 | 6392 | } |
925d519a PZ |
6393 | } |
6394 | ||
97ba62b2 ME |
6395 | static void perf_sigtrap(struct perf_event *event) |
6396 | { | |
6397 | struct kernel_siginfo info; | |
6398 | ||
6399 | /* | |
6400 | * We'd expect this to only occur if the irq_work is delayed and either | |
6401 | * ctx->task or current has changed in the meantime. This can be the | |
6402 | * case on architectures that do not implement arch_irq_work_raise(). | |
6403 | */ | |
6404 | if (WARN_ON_ONCE(event->ctx->task != current)) | |
6405 | return; | |
6406 | ||
6407 | /* | |
6408 | * perf_pending_event() can race with the task exiting. | |
6409 | */ | |
6410 | if (current->flags & PF_EXITING) | |
6411 | return; | |
6412 | ||
6413 | clear_siginfo(&info); | |
6414 | info.si_signo = SIGTRAP; | |
6415 | info.si_code = TRAP_PERF; | |
6416 | info.si_errno = event->attr.type; | |
6417 | info.si_perf = event->attr.sig_data; | |
6418 | info.si_addr = (void __user *)event->pending_addr; | |
6419 | force_sig_info(&info); | |
6420 | } | |
6421 | ||
1d54ad94 PZ |
6422 | static void perf_pending_event_disable(struct perf_event *event) |
6423 | { | |
6424 | int cpu = READ_ONCE(event->pending_disable); | |
6425 | ||
6426 | if (cpu < 0) | |
6427 | return; | |
6428 | ||
6429 | if (cpu == smp_processor_id()) { | |
6430 | WRITE_ONCE(event->pending_disable, -1); | |
97ba62b2 ME |
6431 | |
6432 | if (event->attr.sigtrap) { | |
6433 | perf_sigtrap(event); | |
6434 | atomic_set_release(&event->event_limit, 1); /* rearm event */ | |
6435 | return; | |
6436 | } | |
6437 | ||
1d54ad94 PZ |
6438 | perf_event_disable_local(event); |
6439 | return; | |
6440 | } | |
6441 | ||
6442 | /* | |
6443 | * CPU-A CPU-B | |
6444 | * | |
6445 | * perf_event_disable_inatomic() | |
6446 | * @pending_disable = CPU-A; | |
6447 | * irq_work_queue(); | |
6448 | * | |
6449 | * sched-out | |
6450 | * @pending_disable = -1; | |
6451 | * | |
6452 | * sched-in | |
6453 | * perf_event_disable_inatomic() | |
6454 | * @pending_disable = CPU-B; | |
6455 | * irq_work_queue(); // FAILS | |
6456 | * | |
6457 | * irq_work_run() | |
6458 | * perf_pending_event() | |
6459 | * | |
6460 | * But the event runs on CPU-B and wants disabling there. | |
6461 | */ | |
6462 | irq_work_queue_on(&event->pending, cpu); | |
6463 | } | |
6464 | ||
e360adbe | 6465 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6466 | { |
1d54ad94 | 6467 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6468 | int rctx; |
6469 | ||
6470 | rctx = perf_swevent_get_recursion_context(); | |
6471 | /* | |
6472 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6473 | * and we won't recurse 'further'. | |
6474 | */ | |
79f14641 | 6475 | |
1d54ad94 | 6476 | perf_pending_event_disable(event); |
79f14641 | 6477 | |
cdd6c482 IM |
6478 | if (event->pending_wakeup) { |
6479 | event->pending_wakeup = 0; | |
6480 | perf_event_wakeup(event); | |
79f14641 | 6481 | } |
d525211f PZ |
6482 | |
6483 | if (rctx >= 0) | |
6484 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6485 | } |
6486 | ||
39447b38 ZY |
6487 | /* |
6488 | * We assume there is only KVM supporting the callbacks. | |
6489 | * Later on, we might change it to a list if there is | |
6490 | * another virtualization implementation supporting the callbacks. | |
6491 | */ | |
6492 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6493 | ||
6494 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6495 | { | |
6496 | perf_guest_cbs = cbs; | |
6497 | return 0; | |
6498 | } | |
6499 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6500 | ||
6501 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6502 | { | |
6503 | perf_guest_cbs = NULL; | |
6504 | return 0; | |
6505 | } | |
6506 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6507 | ||
4018994f JO |
6508 | static void |
6509 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6510 | struct pt_regs *regs, u64 mask) | |
6511 | { | |
6512 | int bit; | |
29dd3288 | 6513 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6514 | |
29dd3288 MS |
6515 | bitmap_from_u64(_mask, mask); |
6516 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6517 | u64 val; |
6518 | ||
6519 | val = perf_reg_value(regs, bit); | |
6520 | perf_output_put(handle, val); | |
6521 | } | |
6522 | } | |
6523 | ||
60e2364e | 6524 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
76a4efa8 | 6525 | struct pt_regs *regs) |
4018994f | 6526 | { |
88a7c26a AL |
6527 | if (user_mode(regs)) { |
6528 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6529 | regs_user->regs = regs; |
085ebfe9 | 6530 | } else if (!(current->flags & PF_KTHREAD)) { |
76a4efa8 | 6531 | perf_get_regs_user(regs_user, regs); |
2565711f PZ |
6532 | } else { |
6533 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6534 | regs_user->regs = NULL; | |
4018994f JO |
6535 | } |
6536 | } | |
6537 | ||
60e2364e SE |
6538 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6539 | struct pt_regs *regs) | |
6540 | { | |
6541 | regs_intr->regs = regs; | |
6542 | regs_intr->abi = perf_reg_abi(current); | |
6543 | } | |
6544 | ||
6545 | ||
c5ebcedb JO |
6546 | /* |
6547 | * Get remaining task size from user stack pointer. | |
6548 | * | |
6549 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6550 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6551 | * so using TASK_SIZE as limit. |
6552 | */ | |
6553 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6554 | { | |
6555 | unsigned long addr = perf_user_stack_pointer(regs); | |
6556 | ||
6557 | if (!addr || addr >= TASK_SIZE) | |
6558 | return 0; | |
6559 | ||
6560 | return TASK_SIZE - addr; | |
6561 | } | |
6562 | ||
6563 | static u16 | |
6564 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6565 | struct pt_regs *regs) | |
6566 | { | |
6567 | u64 task_size; | |
6568 | ||
6569 | /* No regs, no stack pointer, no dump. */ | |
6570 | if (!regs) | |
6571 | return 0; | |
6572 | ||
6573 | /* | |
6574 | * Check if we fit in with the requested stack size into the: | |
6575 | * - TASK_SIZE | |
6576 | * If we don't, we limit the size to the TASK_SIZE. | |
6577 | * | |
6578 | * - remaining sample size | |
6579 | * If we don't, we customize the stack size to | |
6580 | * fit in to the remaining sample size. | |
6581 | */ | |
6582 | ||
6583 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6584 | stack_size = min(stack_size, (u16) task_size); | |
6585 | ||
6586 | /* Current header size plus static size and dynamic size. */ | |
6587 | header_size += 2 * sizeof(u64); | |
6588 | ||
6589 | /* Do we fit in with the current stack dump size? */ | |
6590 | if ((u16) (header_size + stack_size) < header_size) { | |
6591 | /* | |
6592 | * If we overflow the maximum size for the sample, | |
6593 | * we customize the stack dump size to fit in. | |
6594 | */ | |
6595 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6596 | stack_size = round_up(stack_size, sizeof(u64)); | |
6597 | } | |
6598 | ||
6599 | return stack_size; | |
6600 | } | |
6601 | ||
6602 | static void | |
6603 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6604 | struct pt_regs *regs) | |
6605 | { | |
6606 | /* Case of a kernel thread, nothing to dump */ | |
6607 | if (!regs) { | |
6608 | u64 size = 0; | |
6609 | perf_output_put(handle, size); | |
6610 | } else { | |
6611 | unsigned long sp; | |
6612 | unsigned int rem; | |
6613 | u64 dyn_size; | |
02e18447 | 6614 | mm_segment_t fs; |
c5ebcedb JO |
6615 | |
6616 | /* | |
6617 | * We dump: | |
6618 | * static size | |
6619 | * - the size requested by user or the best one we can fit | |
6620 | * in to the sample max size | |
6621 | * data | |
6622 | * - user stack dump data | |
6623 | * dynamic size | |
6624 | * - the actual dumped size | |
6625 | */ | |
6626 | ||
6627 | /* Static size. */ | |
6628 | perf_output_put(handle, dump_size); | |
6629 | ||
6630 | /* Data. */ | |
6631 | sp = perf_user_stack_pointer(regs); | |
3d13f313 | 6632 | fs = force_uaccess_begin(); |
c5ebcedb | 6633 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
3d13f313 | 6634 | force_uaccess_end(fs); |
c5ebcedb JO |
6635 | dyn_size = dump_size - rem; |
6636 | ||
6637 | perf_output_skip(handle, rem); | |
6638 | ||
6639 | /* Dynamic size. */ | |
6640 | perf_output_put(handle, dyn_size); | |
6641 | } | |
6642 | } | |
6643 | ||
a4faf00d AS |
6644 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6645 | struct perf_sample_data *data, | |
6646 | size_t size) | |
6647 | { | |
6648 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6649 | struct perf_buffer *rb; |
a4faf00d AS |
6650 | |
6651 | data->aux_size = 0; | |
6652 | ||
6653 | if (!sampler) | |
6654 | goto out; | |
6655 | ||
6656 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6657 | goto out; | |
6658 | ||
6659 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6660 | goto out; | |
6661 | ||
6662 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6663 | if (!rb) | |
6664 | goto out; | |
6665 | ||
6666 | /* | |
6667 | * If this is an NMI hit inside sampling code, don't take | |
6668 | * the sample. See also perf_aux_sample_output(). | |
6669 | */ | |
6670 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6671 | data->aux_size = 0; | |
6672 | } else { | |
6673 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6674 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6675 | } | |
6676 | ring_buffer_put(rb); | |
6677 | ||
6678 | out: | |
6679 | return data->aux_size; | |
6680 | } | |
6681 | ||
56de4e8f | 6682 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6683 | struct perf_event *event, |
6684 | struct perf_output_handle *handle, | |
6685 | unsigned long size) | |
6686 | { | |
6687 | unsigned long flags; | |
6688 | long ret; | |
6689 | ||
6690 | /* | |
6691 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6692 | * paths. If we start calling them in NMI context, they may race with | |
6693 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6694 | * been stopped, which is why we're using a separate callback that | |
6695 | * doesn't change the event state. | |
6696 | * | |
6697 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6698 | */ | |
6699 | local_irq_save(flags); | |
6700 | /* | |
6701 | * Guard against NMI hits inside the critical section; | |
6702 | * see also perf_prepare_sample_aux(). | |
6703 | */ | |
6704 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6705 | barrier(); | |
6706 | ||
6707 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6708 | ||
6709 | barrier(); | |
6710 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6711 | local_irq_restore(flags); | |
6712 | ||
6713 | return ret; | |
6714 | } | |
6715 | ||
6716 | static void perf_aux_sample_output(struct perf_event *event, | |
6717 | struct perf_output_handle *handle, | |
6718 | struct perf_sample_data *data) | |
6719 | { | |
6720 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6721 | struct perf_buffer *rb; |
a4faf00d | 6722 | unsigned long pad; |
a4faf00d AS |
6723 | long size; |
6724 | ||
6725 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6726 | return; | |
6727 | ||
6728 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6729 | if (!rb) | |
6730 | return; | |
6731 | ||
6732 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6733 | ||
6734 | /* | |
6735 | * An error here means that perf_output_copy() failed (returned a | |
6736 | * non-zero surplus that it didn't copy), which in its current | |
6737 | * enlightened implementation is not possible. If that changes, we'd | |
6738 | * like to know. | |
6739 | */ | |
6740 | if (WARN_ON_ONCE(size < 0)) | |
6741 | goto out_put; | |
6742 | ||
6743 | /* | |
6744 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6745 | * perf_prepare_sample_aux(), so should not be more than that. | |
6746 | */ | |
6747 | pad = data->aux_size - size; | |
6748 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6749 | pad = 8; | |
6750 | ||
6751 | if (pad) { | |
6752 | u64 zero = 0; | |
6753 | perf_output_copy(handle, &zero, pad); | |
6754 | } | |
6755 | ||
6756 | out_put: | |
6757 | ring_buffer_put(rb); | |
6758 | } | |
6759 | ||
c980d109 ACM |
6760 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6761 | struct perf_sample_data *data, | |
6762 | struct perf_event *event) | |
6844c09d ACM |
6763 | { |
6764 | u64 sample_type = event->attr.sample_type; | |
6765 | ||
6766 | data->type = sample_type; | |
6767 | header->size += event->id_header_size; | |
6768 | ||
6769 | if (sample_type & PERF_SAMPLE_TID) { | |
6770 | /* namespace issues */ | |
6771 | data->tid_entry.pid = perf_event_pid(event, current); | |
6772 | data->tid_entry.tid = perf_event_tid(event, current); | |
6773 | } | |
6774 | ||
6775 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6776 | data->time = perf_event_clock(event); |
6844c09d | 6777 | |
ff3d527c | 6778 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6779 | data->id = primary_event_id(event); |
6780 | ||
6781 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6782 | data->stream_id = event->id; | |
6783 | ||
6784 | if (sample_type & PERF_SAMPLE_CPU) { | |
6785 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6786 | data->cpu_entry.reserved = 0; | |
6787 | } | |
6788 | } | |
6789 | ||
76369139 FW |
6790 | void perf_event_header__init_id(struct perf_event_header *header, |
6791 | struct perf_sample_data *data, | |
6792 | struct perf_event *event) | |
c980d109 ACM |
6793 | { |
6794 | if (event->attr.sample_id_all) | |
6795 | __perf_event_header__init_id(header, data, event); | |
6796 | } | |
6797 | ||
6798 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6799 | struct perf_sample_data *data) | |
6800 | { | |
6801 | u64 sample_type = data->type; | |
6802 | ||
6803 | if (sample_type & PERF_SAMPLE_TID) | |
6804 | perf_output_put(handle, data->tid_entry); | |
6805 | ||
6806 | if (sample_type & PERF_SAMPLE_TIME) | |
6807 | perf_output_put(handle, data->time); | |
6808 | ||
6809 | if (sample_type & PERF_SAMPLE_ID) | |
6810 | perf_output_put(handle, data->id); | |
6811 | ||
6812 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6813 | perf_output_put(handle, data->stream_id); | |
6814 | ||
6815 | if (sample_type & PERF_SAMPLE_CPU) | |
6816 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6817 | |
6818 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6819 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6820 | } |
6821 | ||
76369139 FW |
6822 | void perf_event__output_id_sample(struct perf_event *event, |
6823 | struct perf_output_handle *handle, | |
6824 | struct perf_sample_data *sample) | |
c980d109 ACM |
6825 | { |
6826 | if (event->attr.sample_id_all) | |
6827 | __perf_event__output_id_sample(handle, sample); | |
6828 | } | |
6829 | ||
3dab77fb | 6830 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6831 | struct perf_event *event, |
6832 | u64 enabled, u64 running) | |
3dab77fb | 6833 | { |
cdd6c482 | 6834 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6835 | u64 values[4]; |
6836 | int n = 0; | |
6837 | ||
b5e58793 | 6838 | values[n++] = perf_event_count(event); |
3dab77fb | 6839 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6840 | values[n++] = enabled + |
cdd6c482 | 6841 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6842 | } |
6843 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6844 | values[n++] = running + |
cdd6c482 | 6845 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6846 | } |
6847 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6848 | values[n++] = primary_event_id(event); |
3dab77fb | 6849 | |
76369139 | 6850 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6851 | } |
6852 | ||
3dab77fb | 6853 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6854 | struct perf_event *event, |
6855 | u64 enabled, u64 running) | |
3dab77fb | 6856 | { |
cdd6c482 IM |
6857 | struct perf_event *leader = event->group_leader, *sub; |
6858 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6859 | u64 values[5]; |
6860 | int n = 0; | |
6861 | ||
6862 | values[n++] = 1 + leader->nr_siblings; | |
6863 | ||
6864 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6865 | values[n++] = enabled; |
3dab77fb PZ |
6866 | |
6867 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6868 | values[n++] = running; |
3dab77fb | 6869 | |
9e5b127d PZ |
6870 | if ((leader != event) && |
6871 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6872 | leader->pmu->read(leader); |
6873 | ||
b5e58793 | 6874 | values[n++] = perf_event_count(leader); |
3dab77fb | 6875 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6876 | values[n++] = primary_event_id(leader); |
3dab77fb | 6877 | |
76369139 | 6878 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6879 | |
edb39592 | 6880 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6881 | n = 0; |
6882 | ||
6f5ab001 JO |
6883 | if ((sub != event) && |
6884 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6885 | sub->pmu->read(sub); |
6886 | ||
b5e58793 | 6887 | values[n++] = perf_event_count(sub); |
3dab77fb | 6888 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6889 | values[n++] = primary_event_id(sub); |
3dab77fb | 6890 | |
76369139 | 6891 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6892 | } |
6893 | } | |
6894 | ||
eed01528 SE |
6895 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6896 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6897 | ||
ba5213ae PZ |
6898 | /* |
6899 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6900 | * | |
6901 | * The problem is that its both hard and excessively expensive to iterate the | |
6902 | * child list, not to mention that its impossible to IPI the children running | |
6903 | * on another CPU, from interrupt/NMI context. | |
6904 | */ | |
3dab77fb | 6905 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6906 | struct perf_event *event) |
3dab77fb | 6907 | { |
e3f3541c | 6908 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6909 | u64 read_format = event->attr.read_format; |
6910 | ||
6911 | /* | |
6912 | * compute total_time_enabled, total_time_running | |
6913 | * based on snapshot values taken when the event | |
6914 | * was last scheduled in. | |
6915 | * | |
6916 | * we cannot simply called update_context_time() | |
6917 | * because of locking issue as we are called in | |
6918 | * NMI context | |
6919 | */ | |
c4794295 | 6920 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6921 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6922 | |
cdd6c482 | 6923 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6924 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6925 | else |
eed01528 | 6926 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6927 | } |
6928 | ||
bbfd5e4f KL |
6929 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6930 | { | |
6931 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6932 | } | |
6933 | ||
5622f295 MM |
6934 | void perf_output_sample(struct perf_output_handle *handle, |
6935 | struct perf_event_header *header, | |
6936 | struct perf_sample_data *data, | |
cdd6c482 | 6937 | struct perf_event *event) |
5622f295 MM |
6938 | { |
6939 | u64 sample_type = data->type; | |
6940 | ||
6941 | perf_output_put(handle, *header); | |
6942 | ||
ff3d527c AH |
6943 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6944 | perf_output_put(handle, data->id); | |
6945 | ||
5622f295 MM |
6946 | if (sample_type & PERF_SAMPLE_IP) |
6947 | perf_output_put(handle, data->ip); | |
6948 | ||
6949 | if (sample_type & PERF_SAMPLE_TID) | |
6950 | perf_output_put(handle, data->tid_entry); | |
6951 | ||
6952 | if (sample_type & PERF_SAMPLE_TIME) | |
6953 | perf_output_put(handle, data->time); | |
6954 | ||
6955 | if (sample_type & PERF_SAMPLE_ADDR) | |
6956 | perf_output_put(handle, data->addr); | |
6957 | ||
6958 | if (sample_type & PERF_SAMPLE_ID) | |
6959 | perf_output_put(handle, data->id); | |
6960 | ||
6961 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6962 | perf_output_put(handle, data->stream_id); | |
6963 | ||
6964 | if (sample_type & PERF_SAMPLE_CPU) | |
6965 | perf_output_put(handle, data->cpu_entry); | |
6966 | ||
6967 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6968 | perf_output_put(handle, data->period); | |
6969 | ||
6970 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6971 | perf_output_read(handle, event); |
5622f295 MM |
6972 | |
6973 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6974 | int size = 1; |
5622f295 | 6975 | |
99e818cc JO |
6976 | size += data->callchain->nr; |
6977 | size *= sizeof(u64); | |
6978 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6979 | } |
6980 | ||
6981 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6982 | struct perf_raw_record *raw = data->raw; |
6983 | ||
6984 | if (raw) { | |
6985 | struct perf_raw_frag *frag = &raw->frag; | |
6986 | ||
6987 | perf_output_put(handle, raw->size); | |
6988 | do { | |
6989 | if (frag->copy) { | |
6990 | __output_custom(handle, frag->copy, | |
6991 | frag->data, frag->size); | |
6992 | } else { | |
6993 | __output_copy(handle, frag->data, | |
6994 | frag->size); | |
6995 | } | |
6996 | if (perf_raw_frag_last(frag)) | |
6997 | break; | |
6998 | frag = frag->next; | |
6999 | } while (1); | |
7000 | if (frag->pad) | |
7001 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
7002 | } else { |
7003 | struct { | |
7004 | u32 size; | |
7005 | u32 data; | |
7006 | } raw = { | |
7007 | .size = sizeof(u32), | |
7008 | .data = 0, | |
7009 | }; | |
7010 | perf_output_put(handle, raw); | |
7011 | } | |
7012 | } | |
a7ac67ea | 7013 | |
bce38cd5 SE |
7014 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
7015 | if (data->br_stack) { | |
7016 | size_t size; | |
7017 | ||
7018 | size = data->br_stack->nr | |
7019 | * sizeof(struct perf_branch_entry); | |
7020 | ||
7021 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
7022 | if (perf_sample_save_hw_index(event)) |
7023 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
7024 | perf_output_copy(handle, data->br_stack->entries, size); |
7025 | } else { | |
7026 | /* | |
7027 | * we always store at least the value of nr | |
7028 | */ | |
7029 | u64 nr = 0; | |
7030 | perf_output_put(handle, nr); | |
7031 | } | |
7032 | } | |
4018994f JO |
7033 | |
7034 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
7035 | u64 abi = data->regs_user.abi; | |
7036 | ||
7037 | /* | |
7038 | * If there are no regs to dump, notice it through | |
7039 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
7040 | */ | |
7041 | perf_output_put(handle, abi); | |
7042 | ||
7043 | if (abi) { | |
7044 | u64 mask = event->attr.sample_regs_user; | |
7045 | perf_output_sample_regs(handle, | |
7046 | data->regs_user.regs, | |
7047 | mask); | |
7048 | } | |
7049 | } | |
c5ebcedb | 7050 | |
a5cdd40c | 7051 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
7052 | perf_output_sample_ustack(handle, |
7053 | data->stack_user_size, | |
7054 | data->regs_user.regs); | |
a5cdd40c | 7055 | } |
c3feedf2 | 7056 | |
2a6c6b7d KL |
7057 | if (sample_type & PERF_SAMPLE_WEIGHT_TYPE) |
7058 | perf_output_put(handle, data->weight.full); | |
d6be9ad6 SE |
7059 | |
7060 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
7061 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 7062 | |
fdfbbd07 AK |
7063 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
7064 | perf_output_put(handle, data->txn); | |
7065 | ||
60e2364e SE |
7066 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
7067 | u64 abi = data->regs_intr.abi; | |
7068 | /* | |
7069 | * If there are no regs to dump, notice it through | |
7070 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
7071 | */ | |
7072 | perf_output_put(handle, abi); | |
7073 | ||
7074 | if (abi) { | |
7075 | u64 mask = event->attr.sample_regs_intr; | |
7076 | ||
7077 | perf_output_sample_regs(handle, | |
7078 | data->regs_intr.regs, | |
7079 | mask); | |
7080 | } | |
7081 | } | |
7082 | ||
fc7ce9c7 KL |
7083 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
7084 | perf_output_put(handle, data->phys_addr); | |
7085 | ||
6546b19f NK |
7086 | if (sample_type & PERF_SAMPLE_CGROUP) |
7087 | perf_output_put(handle, data->cgroup); | |
7088 | ||
8d97e718 KL |
7089 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
7090 | perf_output_put(handle, data->data_page_size); | |
7091 | ||
995f088e SE |
7092 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7093 | perf_output_put(handle, data->code_page_size); | |
7094 | ||
a4faf00d AS |
7095 | if (sample_type & PERF_SAMPLE_AUX) { |
7096 | perf_output_put(handle, data->aux_size); | |
7097 | ||
7098 | if (data->aux_size) | |
7099 | perf_aux_sample_output(event, handle, data); | |
7100 | } | |
7101 | ||
a5cdd40c PZ |
7102 | if (!event->attr.watermark) { |
7103 | int wakeup_events = event->attr.wakeup_events; | |
7104 | ||
7105 | if (wakeup_events) { | |
56de4e8f | 7106 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
7107 | int events = local_inc_return(&rb->events); |
7108 | ||
7109 | if (events >= wakeup_events) { | |
7110 | local_sub(wakeup_events, &rb->events); | |
7111 | local_inc(&rb->wakeup); | |
7112 | } | |
7113 | } | |
7114 | } | |
5622f295 MM |
7115 | } |
7116 | ||
fc7ce9c7 KL |
7117 | static u64 perf_virt_to_phys(u64 virt) |
7118 | { | |
7119 | u64 phys_addr = 0; | |
7120 | struct page *p = NULL; | |
7121 | ||
7122 | if (!virt) | |
7123 | return 0; | |
7124 | ||
7125 | if (virt >= TASK_SIZE) { | |
7126 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
7127 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
7128 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
7129 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
7130 | } else { | |
7131 | /* | |
7132 | * Walking the pages tables for user address. | |
7133 | * Interrupts are disabled, so it prevents any tear down | |
7134 | * of the page tables. | |
dadbb612 | 7135 | * Try IRQ-safe get_user_page_fast_only first. |
fc7ce9c7 KL |
7136 | * If failed, leave phys_addr as 0. |
7137 | */ | |
d3296fb3 JO |
7138 | if (current->mm != NULL) { |
7139 | pagefault_disable(); | |
dadbb612 | 7140 | if (get_user_page_fast_only(virt, 0, &p)) |
d3296fb3 JO |
7141 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; |
7142 | pagefault_enable(); | |
7143 | } | |
fc7ce9c7 KL |
7144 | |
7145 | if (p) | |
7146 | put_page(p); | |
7147 | } | |
7148 | ||
7149 | return phys_addr; | |
7150 | } | |
7151 | ||
8d97e718 | 7152 | /* |
8af26be0 | 7153 | * Return the pagetable size of a given virtual address. |
8d97e718 | 7154 | */ |
8af26be0 | 7155 | static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) |
8d97e718 | 7156 | { |
8af26be0 | 7157 | u64 size = 0; |
8d97e718 | 7158 | |
8af26be0 PZ |
7159 | #ifdef CONFIG_HAVE_FAST_GUP |
7160 | pgd_t *pgdp, pgd; | |
7161 | p4d_t *p4dp, p4d; | |
7162 | pud_t *pudp, pud; | |
7163 | pmd_t *pmdp, pmd; | |
7164 | pte_t *ptep, pte; | |
8d97e718 | 7165 | |
8af26be0 PZ |
7166 | pgdp = pgd_offset(mm, addr); |
7167 | pgd = READ_ONCE(*pgdp); | |
7168 | if (pgd_none(pgd)) | |
8d97e718 KL |
7169 | return 0; |
7170 | ||
8af26be0 PZ |
7171 | if (pgd_leaf(pgd)) |
7172 | return pgd_leaf_size(pgd); | |
8d97e718 | 7173 | |
8af26be0 PZ |
7174 | p4dp = p4d_offset_lockless(pgdp, pgd, addr); |
7175 | p4d = READ_ONCE(*p4dp); | |
7176 | if (!p4d_present(p4d)) | |
8d97e718 KL |
7177 | return 0; |
7178 | ||
8af26be0 PZ |
7179 | if (p4d_leaf(p4d)) |
7180 | return p4d_leaf_size(p4d); | |
8d97e718 | 7181 | |
8af26be0 PZ |
7182 | pudp = pud_offset_lockless(p4dp, p4d, addr); |
7183 | pud = READ_ONCE(*pudp); | |
7184 | if (!pud_present(pud)) | |
8d97e718 KL |
7185 | return 0; |
7186 | ||
8af26be0 PZ |
7187 | if (pud_leaf(pud)) |
7188 | return pud_leaf_size(pud); | |
8d97e718 | 7189 | |
8af26be0 PZ |
7190 | pmdp = pmd_offset_lockless(pudp, pud, addr); |
7191 | pmd = READ_ONCE(*pmdp); | |
7192 | if (!pmd_present(pmd)) | |
8d97e718 | 7193 | return 0; |
8d97e718 | 7194 | |
8af26be0 PZ |
7195 | if (pmd_leaf(pmd)) |
7196 | return pmd_leaf_size(pmd); | |
51b646b2 | 7197 | |
8af26be0 PZ |
7198 | ptep = pte_offset_map(&pmd, addr); |
7199 | pte = ptep_get_lockless(ptep); | |
7200 | if (pte_present(pte)) | |
7201 | size = pte_leaf_size(pte); | |
7202 | pte_unmap(ptep); | |
7203 | #endif /* CONFIG_HAVE_FAST_GUP */ | |
8d97e718 | 7204 | |
8af26be0 | 7205 | return size; |
8d97e718 KL |
7206 | } |
7207 | ||
8d97e718 KL |
7208 | static u64 perf_get_page_size(unsigned long addr) |
7209 | { | |
7210 | struct mm_struct *mm; | |
7211 | unsigned long flags; | |
7212 | u64 size; | |
7213 | ||
7214 | if (!addr) | |
7215 | return 0; | |
7216 | ||
7217 | /* | |
7218 | * Software page-table walkers must disable IRQs, | |
7219 | * which prevents any tear down of the page tables. | |
7220 | */ | |
7221 | local_irq_save(flags); | |
7222 | ||
7223 | mm = current->mm; | |
7224 | if (!mm) { | |
7225 | /* | |
7226 | * For kernel threads and the like, use init_mm so that | |
7227 | * we can find kernel memory. | |
7228 | */ | |
7229 | mm = &init_mm; | |
7230 | } | |
7231 | ||
8af26be0 | 7232 | size = perf_get_pgtable_size(mm, addr); |
8d97e718 KL |
7233 | |
7234 | local_irq_restore(flags); | |
7235 | ||
7236 | return size; | |
7237 | } | |
7238 | ||
99e818cc JO |
7239 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
7240 | ||
6cbc304f | 7241 | struct perf_callchain_entry * |
8cf7e0e2 JO |
7242 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
7243 | { | |
7244 | bool kernel = !event->attr.exclude_callchain_kernel; | |
7245 | bool user = !event->attr.exclude_callchain_user; | |
7246 | /* Disallow cross-task user callchains. */ | |
7247 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
7248 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 7249 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
7250 | |
7251 | if (!kernel && !user) | |
99e818cc | 7252 | return &__empty_callchain; |
8cf7e0e2 | 7253 | |
99e818cc JO |
7254 | callchain = get_perf_callchain(regs, 0, kernel, user, |
7255 | max_stack, crosstask, true); | |
7256 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
7257 | } |
7258 | ||
5622f295 MM |
7259 | void perf_prepare_sample(struct perf_event_header *header, |
7260 | struct perf_sample_data *data, | |
cdd6c482 | 7261 | struct perf_event *event, |
5622f295 | 7262 | struct pt_regs *regs) |
7b732a75 | 7263 | { |
cdd6c482 | 7264 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 7265 | |
cdd6c482 | 7266 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 7267 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
7268 | |
7269 | header->misc = 0; | |
7270 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 7271 | |
c980d109 | 7272 | __perf_event_header__init_id(header, data, event); |
6844c09d | 7273 | |
995f088e | 7274 | if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE)) |
5622f295 MM |
7275 | data->ip = perf_instruction_pointer(regs); |
7276 | ||
b23f3325 | 7277 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 7278 | int size = 1; |
394ee076 | 7279 | |
6cbc304f PZ |
7280 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
7281 | data->callchain = perf_callchain(event, regs); | |
7282 | ||
99e818cc | 7283 | size += data->callchain->nr; |
5622f295 MM |
7284 | |
7285 | header->size += size * sizeof(u64); | |
394ee076 PZ |
7286 | } |
7287 | ||
3a43ce68 | 7288 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
7289 | struct perf_raw_record *raw = data->raw; |
7290 | int size; | |
7291 | ||
7292 | if (raw) { | |
7293 | struct perf_raw_frag *frag = &raw->frag; | |
7294 | u32 sum = 0; | |
7295 | ||
7296 | do { | |
7297 | sum += frag->size; | |
7298 | if (perf_raw_frag_last(frag)) | |
7299 | break; | |
7300 | frag = frag->next; | |
7301 | } while (1); | |
7302 | ||
7303 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
7304 | raw->size = size - sizeof(u32); | |
7305 | frag->pad = raw->size - sum; | |
7306 | } else { | |
7307 | size = sizeof(u64); | |
7308 | } | |
a044560c | 7309 | |
7e3f977e | 7310 | header->size += size; |
7f453c24 | 7311 | } |
bce38cd5 SE |
7312 | |
7313 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7314 | int size = sizeof(u64); /* nr */ | |
7315 | if (data->br_stack) { | |
bbfd5e4f KL |
7316 | if (perf_sample_save_hw_index(event)) |
7317 | size += sizeof(u64); | |
7318 | ||
bce38cd5 SE |
7319 | size += data->br_stack->nr |
7320 | * sizeof(struct perf_branch_entry); | |
7321 | } | |
7322 | header->size += size; | |
7323 | } | |
4018994f | 7324 | |
2565711f | 7325 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
76a4efa8 | 7326 | perf_sample_regs_user(&data->regs_user, regs); |
2565711f | 7327 | |
4018994f JO |
7328 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7329 | /* regs dump ABI info */ | |
7330 | int size = sizeof(u64); | |
7331 | ||
4018994f JO |
7332 | if (data->regs_user.regs) { |
7333 | u64 mask = event->attr.sample_regs_user; | |
7334 | size += hweight64(mask) * sizeof(u64); | |
7335 | } | |
7336 | ||
7337 | header->size += size; | |
7338 | } | |
c5ebcedb JO |
7339 | |
7340 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7341 | /* | |
9f014e3a | 7342 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7343 | * processed as the last one or have additional check added |
7344 | * in case new sample type is added, because we could eat | |
7345 | * up the rest of the sample size. | |
7346 | */ | |
c5ebcedb JO |
7347 | u16 stack_size = event->attr.sample_stack_user; |
7348 | u16 size = sizeof(u64); | |
7349 | ||
c5ebcedb | 7350 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7351 | data->regs_user.regs); |
c5ebcedb JO |
7352 | |
7353 | /* | |
7354 | * If there is something to dump, add space for the dump | |
7355 | * itself and for the field that tells the dynamic size, | |
7356 | * which is how many have been actually dumped. | |
7357 | */ | |
7358 | if (stack_size) | |
7359 | size += sizeof(u64) + stack_size; | |
7360 | ||
7361 | data->stack_user_size = stack_size; | |
7362 | header->size += size; | |
7363 | } | |
60e2364e SE |
7364 | |
7365 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7366 | /* regs dump ABI info */ | |
7367 | int size = sizeof(u64); | |
7368 | ||
7369 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7370 | ||
7371 | if (data->regs_intr.regs) { | |
7372 | u64 mask = event->attr.sample_regs_intr; | |
7373 | ||
7374 | size += hweight64(mask) * sizeof(u64); | |
7375 | } | |
7376 | ||
7377 | header->size += size; | |
7378 | } | |
fc7ce9c7 KL |
7379 | |
7380 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7381 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7382 | |
6546b19f NK |
7383 | #ifdef CONFIG_CGROUP_PERF |
7384 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7385 | struct cgroup *cgrp; | |
7386 | ||
7387 | /* protected by RCU */ | |
7388 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7389 | data->cgroup = cgroup_id(cgrp); | |
7390 | } | |
7391 | #endif | |
7392 | ||
8d97e718 KL |
7393 | /* |
7394 | * PERF_DATA_PAGE_SIZE requires PERF_SAMPLE_ADDR. If the user doesn't | |
7395 | * require PERF_SAMPLE_ADDR, kernel implicitly retrieve the data->addr, | |
7396 | * but the value will not dump to the userspace. | |
7397 | */ | |
7398 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) | |
7399 | data->data_page_size = perf_get_page_size(data->addr); | |
7400 | ||
995f088e SE |
7401 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7402 | data->code_page_size = perf_get_page_size(data->ip); | |
7403 | ||
a4faf00d AS |
7404 | if (sample_type & PERF_SAMPLE_AUX) { |
7405 | u64 size; | |
7406 | ||
7407 | header->size += sizeof(u64); /* size */ | |
7408 | ||
7409 | /* | |
7410 | * Given the 16bit nature of header::size, an AUX sample can | |
7411 | * easily overflow it, what with all the preceding sample bits. | |
7412 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7413 | * per sample in total (rounded down to 8 byte boundary). | |
7414 | */ | |
7415 | size = min_t(size_t, U16_MAX - header->size, | |
7416 | event->attr.aux_sample_size); | |
7417 | size = rounddown(size, 8); | |
7418 | size = perf_prepare_sample_aux(event, data, size); | |
7419 | ||
7420 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7421 | header->size += size; | |
7422 | } | |
7423 | /* | |
7424 | * If you're adding more sample types here, you likely need to do | |
7425 | * something about the overflowing header::size, like repurpose the | |
7426 | * lowest 3 bits of size, which should be always zero at the moment. | |
7427 | * This raises a more important question, do we really need 512k sized | |
7428 | * samples and why, so good argumentation is in order for whatever you | |
7429 | * do here next. | |
7430 | */ | |
7431 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7432 | } |
7f453c24 | 7433 | |
56201969 | 7434 | static __always_inline int |
9ecda41a WN |
7435 | __perf_event_output(struct perf_event *event, |
7436 | struct perf_sample_data *data, | |
7437 | struct pt_regs *regs, | |
7438 | int (*output_begin)(struct perf_output_handle *, | |
267fb273 | 7439 | struct perf_sample_data *, |
9ecda41a WN |
7440 | struct perf_event *, |
7441 | unsigned int)) | |
5622f295 MM |
7442 | { |
7443 | struct perf_output_handle handle; | |
7444 | struct perf_event_header header; | |
56201969 | 7445 | int err; |
689802b2 | 7446 | |
927c7a9e FW |
7447 | /* protect the callchain buffers */ |
7448 | rcu_read_lock(); | |
7449 | ||
cdd6c482 | 7450 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7451 | |
267fb273 | 7452 | err = output_begin(&handle, data, event, header.size); |
56201969 | 7453 | if (err) |
927c7a9e | 7454 | goto exit; |
0322cd6e | 7455 | |
cdd6c482 | 7456 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7457 | |
8a057d84 | 7458 | perf_output_end(&handle); |
927c7a9e FW |
7459 | |
7460 | exit: | |
7461 | rcu_read_unlock(); | |
56201969 | 7462 | return err; |
0322cd6e PZ |
7463 | } |
7464 | ||
9ecda41a WN |
7465 | void |
7466 | perf_event_output_forward(struct perf_event *event, | |
7467 | struct perf_sample_data *data, | |
7468 | struct pt_regs *regs) | |
7469 | { | |
7470 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7471 | } | |
7472 | ||
7473 | void | |
7474 | perf_event_output_backward(struct perf_event *event, | |
7475 | struct perf_sample_data *data, | |
7476 | struct pt_regs *regs) | |
7477 | { | |
7478 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7479 | } | |
7480 | ||
56201969 | 7481 | int |
9ecda41a WN |
7482 | perf_event_output(struct perf_event *event, |
7483 | struct perf_sample_data *data, | |
7484 | struct pt_regs *regs) | |
7485 | { | |
56201969 | 7486 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7487 | } |
7488 | ||
38b200d6 | 7489 | /* |
cdd6c482 | 7490 | * read event_id |
38b200d6 PZ |
7491 | */ |
7492 | ||
7493 | struct perf_read_event { | |
7494 | struct perf_event_header header; | |
7495 | ||
7496 | u32 pid; | |
7497 | u32 tid; | |
38b200d6 PZ |
7498 | }; |
7499 | ||
7500 | static void | |
cdd6c482 | 7501 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7502 | struct task_struct *task) |
7503 | { | |
7504 | struct perf_output_handle handle; | |
c980d109 | 7505 | struct perf_sample_data sample; |
dfc65094 | 7506 | struct perf_read_event read_event = { |
38b200d6 | 7507 | .header = { |
cdd6c482 | 7508 | .type = PERF_RECORD_READ, |
38b200d6 | 7509 | .misc = 0, |
c320c7b7 | 7510 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7511 | }, |
cdd6c482 IM |
7512 | .pid = perf_event_pid(event, task), |
7513 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7514 | }; |
3dab77fb | 7515 | int ret; |
38b200d6 | 7516 | |
c980d109 | 7517 | perf_event_header__init_id(&read_event.header, &sample, event); |
267fb273 | 7518 | ret = perf_output_begin(&handle, &sample, event, read_event.header.size); |
38b200d6 PZ |
7519 | if (ret) |
7520 | return; | |
7521 | ||
dfc65094 | 7522 | perf_output_put(&handle, read_event); |
cdd6c482 | 7523 | perf_output_read(&handle, event); |
c980d109 | 7524 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7525 | |
38b200d6 PZ |
7526 | perf_output_end(&handle); |
7527 | } | |
7528 | ||
aab5b71e | 7529 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7530 | |
7531 | static void | |
aab5b71e PZ |
7532 | perf_iterate_ctx(struct perf_event_context *ctx, |
7533 | perf_iterate_f output, | |
b73e4fef | 7534 | void *data, bool all) |
52d857a8 JO |
7535 | { |
7536 | struct perf_event *event; | |
7537 | ||
7538 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7539 | if (!all) { |
7540 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7541 | continue; | |
7542 | if (!event_filter_match(event)) | |
7543 | continue; | |
7544 | } | |
7545 | ||
67516844 | 7546 | output(event, data); |
52d857a8 JO |
7547 | } |
7548 | } | |
7549 | ||
aab5b71e | 7550 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7551 | { |
7552 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7553 | struct perf_event *event; | |
7554 | ||
7555 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7556 | /* |
7557 | * Skip events that are not fully formed yet; ensure that | |
7558 | * if we observe event->ctx, both event and ctx will be | |
7559 | * complete enough. See perf_install_in_context(). | |
7560 | */ | |
7561 | if (!smp_load_acquire(&event->ctx)) | |
7562 | continue; | |
7563 | ||
f2fb6bef KL |
7564 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7565 | continue; | |
7566 | if (!event_filter_match(event)) | |
7567 | continue; | |
7568 | output(event, data); | |
7569 | } | |
7570 | } | |
7571 | ||
aab5b71e PZ |
7572 | /* |
7573 | * Iterate all events that need to receive side-band events. | |
7574 | * | |
7575 | * For new callers; ensure that account_pmu_sb_event() includes | |
7576 | * your event, otherwise it might not get delivered. | |
7577 | */ | |
52d857a8 | 7578 | static void |
aab5b71e | 7579 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7580 | struct perf_event_context *task_ctx) |
7581 | { | |
52d857a8 | 7582 | struct perf_event_context *ctx; |
52d857a8 JO |
7583 | int ctxn; |
7584 | ||
aab5b71e PZ |
7585 | rcu_read_lock(); |
7586 | preempt_disable(); | |
7587 | ||
4e93ad60 | 7588 | /* |
aab5b71e PZ |
7589 | * If we have task_ctx != NULL we only notify the task context itself. |
7590 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7591 | * context. |
7592 | */ | |
7593 | if (task_ctx) { | |
aab5b71e PZ |
7594 | perf_iterate_ctx(task_ctx, output, data, false); |
7595 | goto done; | |
4e93ad60 JO |
7596 | } |
7597 | ||
aab5b71e | 7598 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7599 | |
7600 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7601 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7602 | if (ctx) | |
aab5b71e | 7603 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7604 | } |
aab5b71e | 7605 | done: |
f2fb6bef | 7606 | preempt_enable(); |
52d857a8 | 7607 | rcu_read_unlock(); |
95ff4ca2 AS |
7608 | } |
7609 | ||
375637bc AS |
7610 | /* |
7611 | * Clear all file-based filters at exec, they'll have to be | |
7612 | * re-instated when/if these objects are mmapped again. | |
7613 | */ | |
7614 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7615 | { | |
7616 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7617 | struct perf_addr_filter *filter; | |
7618 | unsigned int restart = 0, count = 0; | |
7619 | unsigned long flags; | |
7620 | ||
7621 | if (!has_addr_filter(event)) | |
7622 | return; | |
7623 | ||
7624 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7625 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7626 | if (filter->path.dentry) { |
c60f83b8 AS |
7627 | event->addr_filter_ranges[count].start = 0; |
7628 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7629 | restart++; |
7630 | } | |
7631 | ||
7632 | count++; | |
7633 | } | |
7634 | ||
7635 | if (restart) | |
7636 | event->addr_filters_gen++; | |
7637 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7638 | ||
7639 | if (restart) | |
767ae086 | 7640 | perf_event_stop(event, 1); |
375637bc AS |
7641 | } |
7642 | ||
7643 | void perf_event_exec(void) | |
7644 | { | |
7645 | struct perf_event_context *ctx; | |
7646 | int ctxn; | |
7647 | ||
375637bc | 7648 | for_each_task_context_nr(ctxn) { |
375637bc | 7649 | perf_event_enable_on_exec(ctxn); |
2e498d0a | 7650 | perf_event_remove_on_exec(ctxn); |
375637bc | 7651 | |
2e498d0a ME |
7652 | rcu_read_lock(); |
7653 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7654 | if (ctx) { | |
7655 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, | |
7656 | NULL, true); | |
7657 | } | |
7658 | rcu_read_unlock(); | |
375637bc | 7659 | } |
375637bc AS |
7660 | } |
7661 | ||
95ff4ca2 | 7662 | struct remote_output { |
56de4e8f | 7663 | struct perf_buffer *rb; |
95ff4ca2 AS |
7664 | int err; |
7665 | }; | |
7666 | ||
7667 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7668 | { | |
7669 | struct perf_event *parent = event->parent; | |
7670 | struct remote_output *ro = data; | |
56de4e8f | 7671 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7672 | struct stop_event_data sd = { |
7673 | .event = event, | |
7674 | }; | |
95ff4ca2 AS |
7675 | |
7676 | if (!has_aux(event)) | |
7677 | return; | |
7678 | ||
7679 | if (!parent) | |
7680 | parent = event; | |
7681 | ||
7682 | /* | |
7683 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7684 | * ring-buffer, but it will be the child that's actually using it. |
7685 | * | |
7686 | * We are using event::rb to determine if the event should be stopped, | |
7687 | * however this may race with ring_buffer_attach() (through set_output), | |
7688 | * which will make us skip the event that actually needs to be stopped. | |
7689 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7690 | * its rb pointer. | |
95ff4ca2 AS |
7691 | */ |
7692 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7693 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7694 | } |
7695 | ||
7696 | static int __perf_pmu_output_stop(void *info) | |
7697 | { | |
7698 | struct perf_event *event = info; | |
f3a519e4 | 7699 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7700 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7701 | struct remote_output ro = { |
7702 | .rb = event->rb, | |
7703 | }; | |
7704 | ||
7705 | rcu_read_lock(); | |
aab5b71e | 7706 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7707 | if (cpuctx->task_ctx) |
aab5b71e | 7708 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7709 | &ro, false); |
95ff4ca2 AS |
7710 | rcu_read_unlock(); |
7711 | ||
7712 | return ro.err; | |
7713 | } | |
7714 | ||
7715 | static void perf_pmu_output_stop(struct perf_event *event) | |
7716 | { | |
7717 | struct perf_event *iter; | |
7718 | int err, cpu; | |
7719 | ||
7720 | restart: | |
7721 | rcu_read_lock(); | |
7722 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7723 | /* | |
7724 | * For per-CPU events, we need to make sure that neither they | |
7725 | * nor their children are running; for cpu==-1 events it's | |
7726 | * sufficient to stop the event itself if it's active, since | |
7727 | * it can't have children. | |
7728 | */ | |
7729 | cpu = iter->cpu; | |
7730 | if (cpu == -1) | |
7731 | cpu = READ_ONCE(iter->oncpu); | |
7732 | ||
7733 | if (cpu == -1) | |
7734 | continue; | |
7735 | ||
7736 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7737 | if (err == -EAGAIN) { | |
7738 | rcu_read_unlock(); | |
7739 | goto restart; | |
7740 | } | |
7741 | } | |
7742 | rcu_read_unlock(); | |
52d857a8 JO |
7743 | } |
7744 | ||
60313ebe | 7745 | /* |
9f498cc5 PZ |
7746 | * task tracking -- fork/exit |
7747 | * | |
13d7a241 | 7748 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7749 | */ |
7750 | ||
9f498cc5 | 7751 | struct perf_task_event { |
3a80b4a3 | 7752 | struct task_struct *task; |
cdd6c482 | 7753 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7754 | |
7755 | struct { | |
7756 | struct perf_event_header header; | |
7757 | ||
7758 | u32 pid; | |
7759 | u32 ppid; | |
9f498cc5 PZ |
7760 | u32 tid; |
7761 | u32 ptid; | |
393b2ad8 | 7762 | u64 time; |
cdd6c482 | 7763 | } event_id; |
60313ebe PZ |
7764 | }; |
7765 | ||
67516844 JO |
7766 | static int perf_event_task_match(struct perf_event *event) |
7767 | { | |
13d7a241 SE |
7768 | return event->attr.comm || event->attr.mmap || |
7769 | event->attr.mmap2 || event->attr.mmap_data || | |
7770 | event->attr.task; | |
67516844 JO |
7771 | } |
7772 | ||
cdd6c482 | 7773 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7774 | void *data) |
60313ebe | 7775 | { |
52d857a8 | 7776 | struct perf_task_event *task_event = data; |
60313ebe | 7777 | struct perf_output_handle handle; |
c980d109 | 7778 | struct perf_sample_data sample; |
9f498cc5 | 7779 | struct task_struct *task = task_event->task; |
c980d109 | 7780 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7781 | |
67516844 JO |
7782 | if (!perf_event_task_match(event)) |
7783 | return; | |
7784 | ||
c980d109 | 7785 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7786 | |
267fb273 | 7787 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7788 | task_event->event_id.header.size); |
ef60777c | 7789 | if (ret) |
c980d109 | 7790 | goto out; |
60313ebe | 7791 | |
cdd6c482 | 7792 | task_event->event_id.pid = perf_event_pid(event, task); |
cdd6c482 | 7793 | task_event->event_id.tid = perf_event_tid(event, task); |
f3bed55e IR |
7794 | |
7795 | if (task_event->event_id.header.type == PERF_RECORD_EXIT) { | |
7796 | task_event->event_id.ppid = perf_event_pid(event, | |
7797 | task->real_parent); | |
7798 | task_event->event_id.ptid = perf_event_pid(event, | |
7799 | task->real_parent); | |
7800 | } else { /* PERF_RECORD_FORK */ | |
7801 | task_event->event_id.ppid = perf_event_pid(event, current); | |
7802 | task_event->event_id.ptid = perf_event_tid(event, current); | |
7803 | } | |
9f498cc5 | 7804 | |
34f43927 PZ |
7805 | task_event->event_id.time = perf_event_clock(event); |
7806 | ||
cdd6c482 | 7807 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7808 | |
c980d109 ACM |
7809 | perf_event__output_id_sample(event, &handle, &sample); |
7810 | ||
60313ebe | 7811 | perf_output_end(&handle); |
c980d109 ACM |
7812 | out: |
7813 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7814 | } |
7815 | ||
cdd6c482 IM |
7816 | static void perf_event_task(struct task_struct *task, |
7817 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7818 | int new) |
60313ebe | 7819 | { |
9f498cc5 | 7820 | struct perf_task_event task_event; |
60313ebe | 7821 | |
cdd6c482 IM |
7822 | if (!atomic_read(&nr_comm_events) && |
7823 | !atomic_read(&nr_mmap_events) && | |
7824 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7825 | return; |
7826 | ||
9f498cc5 | 7827 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7828 | .task = task, |
7829 | .task_ctx = task_ctx, | |
cdd6c482 | 7830 | .event_id = { |
60313ebe | 7831 | .header = { |
cdd6c482 | 7832 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7833 | .misc = 0, |
cdd6c482 | 7834 | .size = sizeof(task_event.event_id), |
60313ebe | 7835 | }, |
573402db PZ |
7836 | /* .pid */ |
7837 | /* .ppid */ | |
9f498cc5 PZ |
7838 | /* .tid */ |
7839 | /* .ptid */ | |
34f43927 | 7840 | /* .time */ |
60313ebe PZ |
7841 | }, |
7842 | }; | |
7843 | ||
aab5b71e | 7844 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7845 | &task_event, |
7846 | task_ctx); | |
9f498cc5 PZ |
7847 | } |
7848 | ||
cdd6c482 | 7849 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7850 | { |
cdd6c482 | 7851 | perf_event_task(task, NULL, 1); |
e4222673 | 7852 | perf_event_namespaces(task); |
60313ebe PZ |
7853 | } |
7854 | ||
8d1b2d93 PZ |
7855 | /* |
7856 | * comm tracking | |
7857 | */ | |
7858 | ||
7859 | struct perf_comm_event { | |
22a4f650 IM |
7860 | struct task_struct *task; |
7861 | char *comm; | |
8d1b2d93 PZ |
7862 | int comm_size; |
7863 | ||
7864 | struct { | |
7865 | struct perf_event_header header; | |
7866 | ||
7867 | u32 pid; | |
7868 | u32 tid; | |
cdd6c482 | 7869 | } event_id; |
8d1b2d93 PZ |
7870 | }; |
7871 | ||
67516844 JO |
7872 | static int perf_event_comm_match(struct perf_event *event) |
7873 | { | |
7874 | return event->attr.comm; | |
7875 | } | |
7876 | ||
cdd6c482 | 7877 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7878 | void *data) |
8d1b2d93 | 7879 | { |
52d857a8 | 7880 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7881 | struct perf_output_handle handle; |
c980d109 | 7882 | struct perf_sample_data sample; |
cdd6c482 | 7883 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7884 | int ret; |
7885 | ||
67516844 JO |
7886 | if (!perf_event_comm_match(event)) |
7887 | return; | |
7888 | ||
c980d109 | 7889 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
267fb273 | 7890 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7891 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7892 | |
7893 | if (ret) | |
c980d109 | 7894 | goto out; |
8d1b2d93 | 7895 | |
cdd6c482 IM |
7896 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7897 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7898 | |
cdd6c482 | 7899 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7900 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7901 | comm_event->comm_size); |
c980d109 ACM |
7902 | |
7903 | perf_event__output_id_sample(event, &handle, &sample); | |
7904 | ||
8d1b2d93 | 7905 | perf_output_end(&handle); |
c980d109 ACM |
7906 | out: |
7907 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7908 | } |
7909 | ||
cdd6c482 | 7910 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7911 | { |
413ee3b4 | 7912 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7913 | unsigned int size; |
8d1b2d93 | 7914 | |
413ee3b4 | 7915 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7916 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7917 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7918 | |
7919 | comm_event->comm = comm; | |
7920 | comm_event->comm_size = size; | |
7921 | ||
cdd6c482 | 7922 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7923 | |
aab5b71e | 7924 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7925 | comm_event, |
7926 | NULL); | |
8d1b2d93 PZ |
7927 | } |
7928 | ||
82b89778 | 7929 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7930 | { |
9ee318a7 PZ |
7931 | struct perf_comm_event comm_event; |
7932 | ||
cdd6c482 | 7933 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7934 | return; |
a63eaf34 | 7935 | |
9ee318a7 | 7936 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7937 | .task = task, |
573402db PZ |
7938 | /* .comm */ |
7939 | /* .comm_size */ | |
cdd6c482 | 7940 | .event_id = { |
573402db | 7941 | .header = { |
cdd6c482 | 7942 | .type = PERF_RECORD_COMM, |
82b89778 | 7943 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7944 | /* .size */ |
7945 | }, | |
7946 | /* .pid */ | |
7947 | /* .tid */ | |
8d1b2d93 PZ |
7948 | }, |
7949 | }; | |
7950 | ||
cdd6c482 | 7951 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7952 | } |
7953 | ||
e4222673 HB |
7954 | /* |
7955 | * namespaces tracking | |
7956 | */ | |
7957 | ||
7958 | struct perf_namespaces_event { | |
7959 | struct task_struct *task; | |
7960 | ||
7961 | struct { | |
7962 | struct perf_event_header header; | |
7963 | ||
7964 | u32 pid; | |
7965 | u32 tid; | |
7966 | u64 nr_namespaces; | |
7967 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7968 | } event_id; | |
7969 | }; | |
7970 | ||
7971 | static int perf_event_namespaces_match(struct perf_event *event) | |
7972 | { | |
7973 | return event->attr.namespaces; | |
7974 | } | |
7975 | ||
7976 | static void perf_event_namespaces_output(struct perf_event *event, | |
7977 | void *data) | |
7978 | { | |
7979 | struct perf_namespaces_event *namespaces_event = data; | |
7980 | struct perf_output_handle handle; | |
7981 | struct perf_sample_data sample; | |
34900ec5 | 7982 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7983 | int ret; |
7984 | ||
7985 | if (!perf_event_namespaces_match(event)) | |
7986 | return; | |
7987 | ||
7988 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7989 | &sample, event); | |
267fb273 | 7990 | ret = perf_output_begin(&handle, &sample, event, |
e4222673 HB |
7991 | namespaces_event->event_id.header.size); |
7992 | if (ret) | |
34900ec5 | 7993 | goto out; |
e4222673 HB |
7994 | |
7995 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7996 | namespaces_event->task); | |
7997 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7998 | namespaces_event->task); | |
7999 | ||
8000 | perf_output_put(&handle, namespaces_event->event_id); | |
8001 | ||
8002 | perf_event__output_id_sample(event, &handle, &sample); | |
8003 | ||
8004 | perf_output_end(&handle); | |
34900ec5 JO |
8005 | out: |
8006 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
8007 | } |
8008 | ||
8009 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
8010 | struct task_struct *task, | |
8011 | const struct proc_ns_operations *ns_ops) | |
8012 | { | |
8013 | struct path ns_path; | |
8014 | struct inode *ns_inode; | |
ce623f89 | 8015 | int error; |
e4222673 HB |
8016 | |
8017 | error = ns_get_path(&ns_path, task, ns_ops); | |
8018 | if (!error) { | |
8019 | ns_inode = ns_path.dentry->d_inode; | |
8020 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
8021 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 8022 | path_put(&ns_path); |
e4222673 HB |
8023 | } |
8024 | } | |
8025 | ||
8026 | void perf_event_namespaces(struct task_struct *task) | |
8027 | { | |
8028 | struct perf_namespaces_event namespaces_event; | |
8029 | struct perf_ns_link_info *ns_link_info; | |
8030 | ||
8031 | if (!atomic_read(&nr_namespaces_events)) | |
8032 | return; | |
8033 | ||
8034 | namespaces_event = (struct perf_namespaces_event){ | |
8035 | .task = task, | |
8036 | .event_id = { | |
8037 | .header = { | |
8038 | .type = PERF_RECORD_NAMESPACES, | |
8039 | .misc = 0, | |
8040 | .size = sizeof(namespaces_event.event_id), | |
8041 | }, | |
8042 | /* .pid */ | |
8043 | /* .tid */ | |
8044 | .nr_namespaces = NR_NAMESPACES, | |
8045 | /* .link_info[NR_NAMESPACES] */ | |
8046 | }, | |
8047 | }; | |
8048 | ||
8049 | ns_link_info = namespaces_event.event_id.link_info; | |
8050 | ||
8051 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
8052 | task, &mntns_operations); | |
8053 | ||
8054 | #ifdef CONFIG_USER_NS | |
8055 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
8056 | task, &userns_operations); | |
8057 | #endif | |
8058 | #ifdef CONFIG_NET_NS | |
8059 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
8060 | task, &netns_operations); | |
8061 | #endif | |
8062 | #ifdef CONFIG_UTS_NS | |
8063 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
8064 | task, &utsns_operations); | |
8065 | #endif | |
8066 | #ifdef CONFIG_IPC_NS | |
8067 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
8068 | task, &ipcns_operations); | |
8069 | #endif | |
8070 | #ifdef CONFIG_PID_NS | |
8071 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
8072 | task, &pidns_operations); | |
8073 | #endif | |
8074 | #ifdef CONFIG_CGROUPS | |
8075 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
8076 | task, &cgroupns_operations); | |
8077 | #endif | |
8078 | ||
8079 | perf_iterate_sb(perf_event_namespaces_output, | |
8080 | &namespaces_event, | |
8081 | NULL); | |
8082 | } | |
8083 | ||
96aaab68 NK |
8084 | /* |
8085 | * cgroup tracking | |
8086 | */ | |
8087 | #ifdef CONFIG_CGROUP_PERF | |
8088 | ||
8089 | struct perf_cgroup_event { | |
8090 | char *path; | |
8091 | int path_size; | |
8092 | struct { | |
8093 | struct perf_event_header header; | |
8094 | u64 id; | |
8095 | char path[]; | |
8096 | } event_id; | |
8097 | }; | |
8098 | ||
8099 | static int perf_event_cgroup_match(struct perf_event *event) | |
8100 | { | |
8101 | return event->attr.cgroup; | |
8102 | } | |
8103 | ||
8104 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
8105 | { | |
8106 | struct perf_cgroup_event *cgroup_event = data; | |
8107 | struct perf_output_handle handle; | |
8108 | struct perf_sample_data sample; | |
8109 | u16 header_size = cgroup_event->event_id.header.size; | |
8110 | int ret; | |
8111 | ||
8112 | if (!perf_event_cgroup_match(event)) | |
8113 | return; | |
8114 | ||
8115 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
8116 | &sample, event); | |
267fb273 | 8117 | ret = perf_output_begin(&handle, &sample, event, |
96aaab68 NK |
8118 | cgroup_event->event_id.header.size); |
8119 | if (ret) | |
8120 | goto out; | |
8121 | ||
8122 | perf_output_put(&handle, cgroup_event->event_id); | |
8123 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
8124 | ||
8125 | perf_event__output_id_sample(event, &handle, &sample); | |
8126 | ||
8127 | perf_output_end(&handle); | |
8128 | out: | |
8129 | cgroup_event->event_id.header.size = header_size; | |
8130 | } | |
8131 | ||
8132 | static void perf_event_cgroup(struct cgroup *cgrp) | |
8133 | { | |
8134 | struct perf_cgroup_event cgroup_event; | |
8135 | char path_enomem[16] = "//enomem"; | |
8136 | char *pathname; | |
8137 | size_t size; | |
8138 | ||
8139 | if (!atomic_read(&nr_cgroup_events)) | |
8140 | return; | |
8141 | ||
8142 | cgroup_event = (struct perf_cgroup_event){ | |
8143 | .event_id = { | |
8144 | .header = { | |
8145 | .type = PERF_RECORD_CGROUP, | |
8146 | .misc = 0, | |
8147 | .size = sizeof(cgroup_event.event_id), | |
8148 | }, | |
8149 | .id = cgroup_id(cgrp), | |
8150 | }, | |
8151 | }; | |
8152 | ||
8153 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
8154 | if (pathname == NULL) { | |
8155 | cgroup_event.path = path_enomem; | |
8156 | } else { | |
8157 | /* just to be sure to have enough space for alignment */ | |
8158 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
8159 | cgroup_event.path = pathname; | |
8160 | } | |
8161 | ||
8162 | /* | |
8163 | * Since our buffer works in 8 byte units we need to align our string | |
8164 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8165 | * zero'd out to avoid leaking random bits to userspace. | |
8166 | */ | |
8167 | size = strlen(cgroup_event.path) + 1; | |
8168 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8169 | cgroup_event.path[size++] = '\0'; | |
8170 | ||
8171 | cgroup_event.event_id.header.size += size; | |
8172 | cgroup_event.path_size = size; | |
8173 | ||
8174 | perf_iterate_sb(perf_event_cgroup_output, | |
8175 | &cgroup_event, | |
8176 | NULL); | |
8177 | ||
8178 | kfree(pathname); | |
8179 | } | |
8180 | ||
8181 | #endif | |
8182 | ||
0a4a9391 PZ |
8183 | /* |
8184 | * mmap tracking | |
8185 | */ | |
8186 | ||
8187 | struct perf_mmap_event { | |
089dd79d PZ |
8188 | struct vm_area_struct *vma; |
8189 | ||
8190 | const char *file_name; | |
8191 | int file_size; | |
13d7a241 SE |
8192 | int maj, min; |
8193 | u64 ino; | |
8194 | u64 ino_generation; | |
f972eb63 | 8195 | u32 prot, flags; |
88a16a13 JO |
8196 | u8 build_id[BUILD_ID_SIZE_MAX]; |
8197 | u32 build_id_size; | |
0a4a9391 PZ |
8198 | |
8199 | struct { | |
8200 | struct perf_event_header header; | |
8201 | ||
8202 | u32 pid; | |
8203 | u32 tid; | |
8204 | u64 start; | |
8205 | u64 len; | |
8206 | u64 pgoff; | |
cdd6c482 | 8207 | } event_id; |
0a4a9391 PZ |
8208 | }; |
8209 | ||
67516844 JO |
8210 | static int perf_event_mmap_match(struct perf_event *event, |
8211 | void *data) | |
8212 | { | |
8213 | struct perf_mmap_event *mmap_event = data; | |
8214 | struct vm_area_struct *vma = mmap_event->vma; | |
8215 | int executable = vma->vm_flags & VM_EXEC; | |
8216 | ||
8217 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 8218 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
8219 | } |
8220 | ||
cdd6c482 | 8221 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 8222 | void *data) |
0a4a9391 | 8223 | { |
52d857a8 | 8224 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 8225 | struct perf_output_handle handle; |
c980d109 | 8226 | struct perf_sample_data sample; |
cdd6c482 | 8227 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 8228 | u32 type = mmap_event->event_id.header.type; |
88a16a13 | 8229 | bool use_build_id; |
c980d109 | 8230 | int ret; |
0a4a9391 | 8231 | |
67516844 JO |
8232 | if (!perf_event_mmap_match(event, data)) |
8233 | return; | |
8234 | ||
13d7a241 SE |
8235 | if (event->attr.mmap2) { |
8236 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
8237 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
8238 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
8239 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 8240 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
8241 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
8242 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
8243 | } |
8244 | ||
c980d109 | 8245 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
267fb273 | 8246 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8247 | mmap_event->event_id.header.size); |
0a4a9391 | 8248 | if (ret) |
c980d109 | 8249 | goto out; |
0a4a9391 | 8250 | |
cdd6c482 IM |
8251 | mmap_event->event_id.pid = perf_event_pid(event, current); |
8252 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 8253 | |
88a16a13 JO |
8254 | use_build_id = event->attr.build_id && mmap_event->build_id_size; |
8255 | ||
8256 | if (event->attr.mmap2 && use_build_id) | |
8257 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID; | |
8258 | ||
cdd6c482 | 8259 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
8260 | |
8261 | if (event->attr.mmap2) { | |
88a16a13 JO |
8262 | if (use_build_id) { |
8263 | u8 size[4] = { (u8) mmap_event->build_id_size, 0, 0, 0 }; | |
8264 | ||
8265 | __output_copy(&handle, size, 4); | |
8266 | __output_copy(&handle, mmap_event->build_id, BUILD_ID_SIZE_MAX); | |
8267 | } else { | |
8268 | perf_output_put(&handle, mmap_event->maj); | |
8269 | perf_output_put(&handle, mmap_event->min); | |
8270 | perf_output_put(&handle, mmap_event->ino); | |
8271 | perf_output_put(&handle, mmap_event->ino_generation); | |
8272 | } | |
f972eb63 PZ |
8273 | perf_output_put(&handle, mmap_event->prot); |
8274 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
8275 | } |
8276 | ||
76369139 | 8277 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 8278 | mmap_event->file_size); |
c980d109 ACM |
8279 | |
8280 | perf_event__output_id_sample(event, &handle, &sample); | |
8281 | ||
78d613eb | 8282 | perf_output_end(&handle); |
c980d109 ACM |
8283 | out: |
8284 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 8285 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
8286 | } |
8287 | ||
cdd6c482 | 8288 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 8289 | { |
089dd79d PZ |
8290 | struct vm_area_struct *vma = mmap_event->vma; |
8291 | struct file *file = vma->vm_file; | |
13d7a241 SE |
8292 | int maj = 0, min = 0; |
8293 | u64 ino = 0, gen = 0; | |
f972eb63 | 8294 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
8295 | unsigned int size; |
8296 | char tmp[16]; | |
8297 | char *buf = NULL; | |
2c42cfbf | 8298 | char *name; |
413ee3b4 | 8299 | |
0b3589be PZ |
8300 | if (vma->vm_flags & VM_READ) |
8301 | prot |= PROT_READ; | |
8302 | if (vma->vm_flags & VM_WRITE) | |
8303 | prot |= PROT_WRITE; | |
8304 | if (vma->vm_flags & VM_EXEC) | |
8305 | prot |= PROT_EXEC; | |
8306 | ||
8307 | if (vma->vm_flags & VM_MAYSHARE) | |
8308 | flags = MAP_SHARED; | |
8309 | else | |
8310 | flags = MAP_PRIVATE; | |
8311 | ||
8312 | if (vma->vm_flags & VM_DENYWRITE) | |
8313 | flags |= MAP_DENYWRITE; | |
8314 | if (vma->vm_flags & VM_MAYEXEC) | |
8315 | flags |= MAP_EXECUTABLE; | |
8316 | if (vma->vm_flags & VM_LOCKED) | |
8317 | flags |= MAP_LOCKED; | |
03911132 | 8318 | if (is_vm_hugetlb_page(vma)) |
0b3589be PZ |
8319 | flags |= MAP_HUGETLB; |
8320 | ||
0a4a9391 | 8321 | if (file) { |
13d7a241 SE |
8322 | struct inode *inode; |
8323 | dev_t dev; | |
3ea2f2b9 | 8324 | |
2c42cfbf | 8325 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 8326 | if (!buf) { |
c7e548b4 ON |
8327 | name = "//enomem"; |
8328 | goto cpy_name; | |
0a4a9391 | 8329 | } |
413ee3b4 | 8330 | /* |
3ea2f2b9 | 8331 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
8332 | * need to add enough zero bytes after the string to handle |
8333 | * the 64bit alignment we do later. | |
8334 | */ | |
9bf39ab2 | 8335 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 8336 | if (IS_ERR(name)) { |
c7e548b4 ON |
8337 | name = "//toolong"; |
8338 | goto cpy_name; | |
0a4a9391 | 8339 | } |
13d7a241 SE |
8340 | inode = file_inode(vma->vm_file); |
8341 | dev = inode->i_sb->s_dev; | |
8342 | ino = inode->i_ino; | |
8343 | gen = inode->i_generation; | |
8344 | maj = MAJOR(dev); | |
8345 | min = MINOR(dev); | |
f972eb63 | 8346 | |
c7e548b4 | 8347 | goto got_name; |
0a4a9391 | 8348 | } else { |
fbe26abe JO |
8349 | if (vma->vm_ops && vma->vm_ops->name) { |
8350 | name = (char *) vma->vm_ops->name(vma); | |
8351 | if (name) | |
8352 | goto cpy_name; | |
8353 | } | |
8354 | ||
2c42cfbf | 8355 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8356 | if (name) |
8357 | goto cpy_name; | |
089dd79d | 8358 | |
32c5fb7e | 8359 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8360 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8361 | name = "[heap]"; |
8362 | goto cpy_name; | |
32c5fb7e ON |
8363 | } |
8364 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8365 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8366 | name = "[stack]"; |
8367 | goto cpy_name; | |
089dd79d PZ |
8368 | } |
8369 | ||
c7e548b4 ON |
8370 | name = "//anon"; |
8371 | goto cpy_name; | |
0a4a9391 PZ |
8372 | } |
8373 | ||
c7e548b4 ON |
8374 | cpy_name: |
8375 | strlcpy(tmp, name, sizeof(tmp)); | |
8376 | name = tmp; | |
0a4a9391 | 8377 | got_name: |
2c42cfbf PZ |
8378 | /* |
8379 | * Since our buffer works in 8 byte units we need to align our string | |
8380 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8381 | * zero'd out to avoid leaking random bits to userspace. | |
8382 | */ | |
8383 | size = strlen(name)+1; | |
8384 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8385 | name[size++] = '\0'; | |
0a4a9391 PZ |
8386 | |
8387 | mmap_event->file_name = name; | |
8388 | mmap_event->file_size = size; | |
13d7a241 SE |
8389 | mmap_event->maj = maj; |
8390 | mmap_event->min = min; | |
8391 | mmap_event->ino = ino; | |
8392 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8393 | mmap_event->prot = prot; |
8394 | mmap_event->flags = flags; | |
0a4a9391 | 8395 | |
2fe85427 SE |
8396 | if (!(vma->vm_flags & VM_EXEC)) |
8397 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8398 | ||
cdd6c482 | 8399 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8400 | |
88a16a13 JO |
8401 | if (atomic_read(&nr_build_id_events)) |
8402 | build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size); | |
8403 | ||
aab5b71e | 8404 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8405 | mmap_event, |
8406 | NULL); | |
665c2142 | 8407 | |
0a4a9391 PZ |
8408 | kfree(buf); |
8409 | } | |
8410 | ||
375637bc AS |
8411 | /* |
8412 | * Check whether inode and address range match filter criteria. | |
8413 | */ | |
8414 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8415 | struct file *file, unsigned long offset, | |
8416 | unsigned long size) | |
8417 | { | |
7f635ff1 MP |
8418 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8419 | if (!filter->path.dentry) | |
8420 | return false; | |
8421 | ||
9511bce9 | 8422 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8423 | return false; |
8424 | ||
8425 | if (filter->offset > offset + size) | |
8426 | return false; | |
8427 | ||
8428 | if (filter->offset + filter->size < offset) | |
8429 | return false; | |
8430 | ||
8431 | return true; | |
8432 | } | |
8433 | ||
c60f83b8 AS |
8434 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8435 | struct vm_area_struct *vma, | |
8436 | struct perf_addr_filter_range *fr) | |
8437 | { | |
8438 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8439 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8440 | struct file *file = vma->vm_file; | |
8441 | ||
8442 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8443 | return false; | |
8444 | ||
8445 | if (filter->offset < off) { | |
8446 | fr->start = vma->vm_start; | |
8447 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8448 | } else { | |
8449 | fr->start = vma->vm_start + filter->offset - off; | |
8450 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8451 | } | |
8452 | ||
8453 | return true; | |
8454 | } | |
8455 | ||
375637bc AS |
8456 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8457 | { | |
8458 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8459 | struct vm_area_struct *vma = data; | |
375637bc AS |
8460 | struct perf_addr_filter *filter; |
8461 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8462 | unsigned long flags; |
375637bc AS |
8463 | |
8464 | if (!has_addr_filter(event)) | |
8465 | return; | |
8466 | ||
c60f83b8 | 8467 | if (!vma->vm_file) |
375637bc AS |
8468 | return; |
8469 | ||
8470 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8471 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8472 | if (perf_addr_filter_vma_adjust(filter, vma, |
8473 | &event->addr_filter_ranges[count])) | |
375637bc | 8474 | restart++; |
375637bc AS |
8475 | |
8476 | count++; | |
8477 | } | |
8478 | ||
8479 | if (restart) | |
8480 | event->addr_filters_gen++; | |
8481 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8482 | ||
8483 | if (restart) | |
767ae086 | 8484 | perf_event_stop(event, 1); |
375637bc AS |
8485 | } |
8486 | ||
8487 | /* | |
8488 | * Adjust all task's events' filters to the new vma | |
8489 | */ | |
8490 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8491 | { | |
8492 | struct perf_event_context *ctx; | |
8493 | int ctxn; | |
8494 | ||
12b40a23 MP |
8495 | /* |
8496 | * Data tracing isn't supported yet and as such there is no need | |
8497 | * to keep track of anything that isn't related to executable code: | |
8498 | */ | |
8499 | if (!(vma->vm_flags & VM_EXEC)) | |
8500 | return; | |
8501 | ||
375637bc AS |
8502 | rcu_read_lock(); |
8503 | for_each_task_context_nr(ctxn) { | |
8504 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8505 | if (!ctx) | |
8506 | continue; | |
8507 | ||
aab5b71e | 8508 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8509 | } |
8510 | rcu_read_unlock(); | |
8511 | } | |
8512 | ||
3af9e859 | 8513 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8514 | { |
9ee318a7 PZ |
8515 | struct perf_mmap_event mmap_event; |
8516 | ||
cdd6c482 | 8517 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8518 | return; |
8519 | ||
8520 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8521 | .vma = vma, |
573402db PZ |
8522 | /* .file_name */ |
8523 | /* .file_size */ | |
cdd6c482 | 8524 | .event_id = { |
573402db | 8525 | .header = { |
cdd6c482 | 8526 | .type = PERF_RECORD_MMAP, |
39447b38 | 8527 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8528 | /* .size */ |
8529 | }, | |
8530 | /* .pid */ | |
8531 | /* .tid */ | |
089dd79d PZ |
8532 | .start = vma->vm_start, |
8533 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8534 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8535 | }, |
13d7a241 SE |
8536 | /* .maj (attr_mmap2 only) */ |
8537 | /* .min (attr_mmap2 only) */ | |
8538 | /* .ino (attr_mmap2 only) */ | |
8539 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8540 | /* .prot (attr_mmap2 only) */ |
8541 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8542 | }; |
8543 | ||
375637bc | 8544 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8545 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8546 | } |
8547 | ||
68db7e98 AS |
8548 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8549 | unsigned long size, u64 flags) | |
8550 | { | |
8551 | struct perf_output_handle handle; | |
8552 | struct perf_sample_data sample; | |
8553 | struct perf_aux_event { | |
8554 | struct perf_event_header header; | |
8555 | u64 offset; | |
8556 | u64 size; | |
8557 | u64 flags; | |
8558 | } rec = { | |
8559 | .header = { | |
8560 | .type = PERF_RECORD_AUX, | |
8561 | .misc = 0, | |
8562 | .size = sizeof(rec), | |
8563 | }, | |
8564 | .offset = head, | |
8565 | .size = size, | |
8566 | .flags = flags, | |
8567 | }; | |
8568 | int ret; | |
8569 | ||
8570 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8571 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
68db7e98 AS |
8572 | |
8573 | if (ret) | |
8574 | return; | |
8575 | ||
8576 | perf_output_put(&handle, rec); | |
8577 | perf_event__output_id_sample(event, &handle, &sample); | |
8578 | ||
8579 | perf_output_end(&handle); | |
8580 | } | |
8581 | ||
f38b0dbb KL |
8582 | /* |
8583 | * Lost/dropped samples logging | |
8584 | */ | |
8585 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8586 | { | |
8587 | struct perf_output_handle handle; | |
8588 | struct perf_sample_data sample; | |
8589 | int ret; | |
8590 | ||
8591 | struct { | |
8592 | struct perf_event_header header; | |
8593 | u64 lost; | |
8594 | } lost_samples_event = { | |
8595 | .header = { | |
8596 | .type = PERF_RECORD_LOST_SAMPLES, | |
8597 | .misc = 0, | |
8598 | .size = sizeof(lost_samples_event), | |
8599 | }, | |
8600 | .lost = lost, | |
8601 | }; | |
8602 | ||
8603 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8604 | ||
267fb273 | 8605 | ret = perf_output_begin(&handle, &sample, event, |
f38b0dbb KL |
8606 | lost_samples_event.header.size); |
8607 | if (ret) | |
8608 | return; | |
8609 | ||
8610 | perf_output_put(&handle, lost_samples_event); | |
8611 | perf_event__output_id_sample(event, &handle, &sample); | |
8612 | perf_output_end(&handle); | |
8613 | } | |
8614 | ||
45ac1403 AH |
8615 | /* |
8616 | * context_switch tracking | |
8617 | */ | |
8618 | ||
8619 | struct perf_switch_event { | |
8620 | struct task_struct *task; | |
8621 | struct task_struct *next_prev; | |
8622 | ||
8623 | struct { | |
8624 | struct perf_event_header header; | |
8625 | u32 next_prev_pid; | |
8626 | u32 next_prev_tid; | |
8627 | } event_id; | |
8628 | }; | |
8629 | ||
8630 | static int perf_event_switch_match(struct perf_event *event) | |
8631 | { | |
8632 | return event->attr.context_switch; | |
8633 | } | |
8634 | ||
8635 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8636 | { | |
8637 | struct perf_switch_event *se = data; | |
8638 | struct perf_output_handle handle; | |
8639 | struct perf_sample_data sample; | |
8640 | int ret; | |
8641 | ||
8642 | if (!perf_event_switch_match(event)) | |
8643 | return; | |
8644 | ||
8645 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8646 | if (event->ctx->task) { | |
8647 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8648 | se->event_id.header.size = sizeof(se->event_id.header); | |
8649 | } else { | |
8650 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8651 | se->event_id.header.size = sizeof(se->event_id); | |
8652 | se->event_id.next_prev_pid = | |
8653 | perf_event_pid(event, se->next_prev); | |
8654 | se->event_id.next_prev_tid = | |
8655 | perf_event_tid(event, se->next_prev); | |
8656 | } | |
8657 | ||
8658 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8659 | ||
267fb273 | 8660 | ret = perf_output_begin(&handle, &sample, event, se->event_id.header.size); |
45ac1403 AH |
8661 | if (ret) |
8662 | return; | |
8663 | ||
8664 | if (event->ctx->task) | |
8665 | perf_output_put(&handle, se->event_id.header); | |
8666 | else | |
8667 | perf_output_put(&handle, se->event_id); | |
8668 | ||
8669 | perf_event__output_id_sample(event, &handle, &sample); | |
8670 | ||
8671 | perf_output_end(&handle); | |
8672 | } | |
8673 | ||
8674 | static void perf_event_switch(struct task_struct *task, | |
8675 | struct task_struct *next_prev, bool sched_in) | |
8676 | { | |
8677 | struct perf_switch_event switch_event; | |
8678 | ||
8679 | /* N.B. caller checks nr_switch_events != 0 */ | |
8680 | ||
8681 | switch_event = (struct perf_switch_event){ | |
8682 | .task = task, | |
8683 | .next_prev = next_prev, | |
8684 | .event_id = { | |
8685 | .header = { | |
8686 | /* .type */ | |
8687 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8688 | /* .size */ | |
8689 | }, | |
8690 | /* .next_prev_pid */ | |
8691 | /* .next_prev_tid */ | |
8692 | }, | |
8693 | }; | |
8694 | ||
101592b4 AB |
8695 | if (!sched_in && task->state == TASK_RUNNING) |
8696 | switch_event.event_id.header.misc |= | |
8697 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8698 | ||
aab5b71e | 8699 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8700 | &switch_event, |
8701 | NULL); | |
8702 | } | |
8703 | ||
a78ac325 PZ |
8704 | /* |
8705 | * IRQ throttle logging | |
8706 | */ | |
8707 | ||
cdd6c482 | 8708 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8709 | { |
8710 | struct perf_output_handle handle; | |
c980d109 | 8711 | struct perf_sample_data sample; |
a78ac325 PZ |
8712 | int ret; |
8713 | ||
8714 | struct { | |
8715 | struct perf_event_header header; | |
8716 | u64 time; | |
cca3f454 | 8717 | u64 id; |
7f453c24 | 8718 | u64 stream_id; |
a78ac325 PZ |
8719 | } throttle_event = { |
8720 | .header = { | |
cdd6c482 | 8721 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8722 | .misc = 0, |
8723 | .size = sizeof(throttle_event), | |
8724 | }, | |
34f43927 | 8725 | .time = perf_event_clock(event), |
cdd6c482 IM |
8726 | .id = primary_event_id(event), |
8727 | .stream_id = event->id, | |
a78ac325 PZ |
8728 | }; |
8729 | ||
966ee4d6 | 8730 | if (enable) |
cdd6c482 | 8731 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8732 | |
c980d109 ACM |
8733 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8734 | ||
267fb273 | 8735 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8736 | throttle_event.header.size); |
a78ac325 PZ |
8737 | if (ret) |
8738 | return; | |
8739 | ||
8740 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8741 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8742 | perf_output_end(&handle); |
8743 | } | |
8744 | ||
76193a94 SL |
8745 | /* |
8746 | * ksymbol register/unregister tracking | |
8747 | */ | |
8748 | ||
8749 | struct perf_ksymbol_event { | |
8750 | const char *name; | |
8751 | int name_len; | |
8752 | struct { | |
8753 | struct perf_event_header header; | |
8754 | u64 addr; | |
8755 | u32 len; | |
8756 | u16 ksym_type; | |
8757 | u16 flags; | |
8758 | } event_id; | |
8759 | }; | |
8760 | ||
8761 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8762 | { | |
8763 | return event->attr.ksymbol; | |
8764 | } | |
8765 | ||
8766 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8767 | { | |
8768 | struct perf_ksymbol_event *ksymbol_event = data; | |
8769 | struct perf_output_handle handle; | |
8770 | struct perf_sample_data sample; | |
8771 | int ret; | |
8772 | ||
8773 | if (!perf_event_ksymbol_match(event)) | |
8774 | return; | |
8775 | ||
8776 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8777 | &sample, event); | |
267fb273 | 8778 | ret = perf_output_begin(&handle, &sample, event, |
76193a94 SL |
8779 | ksymbol_event->event_id.header.size); |
8780 | if (ret) | |
8781 | return; | |
8782 | ||
8783 | perf_output_put(&handle, ksymbol_event->event_id); | |
8784 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8785 | perf_event__output_id_sample(event, &handle, &sample); | |
8786 | ||
8787 | perf_output_end(&handle); | |
8788 | } | |
8789 | ||
8790 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8791 | const char *sym) | |
8792 | { | |
8793 | struct perf_ksymbol_event ksymbol_event; | |
8794 | char name[KSYM_NAME_LEN]; | |
8795 | u16 flags = 0; | |
8796 | int name_len; | |
8797 | ||
8798 | if (!atomic_read(&nr_ksymbol_events)) | |
8799 | return; | |
8800 | ||
8801 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8802 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8803 | goto err; | |
8804 | ||
8805 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8806 | name_len = strlen(name) + 1; | |
8807 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8808 | name[name_len++] = '\0'; | |
8809 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8810 | ||
8811 | if (unregister) | |
8812 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8813 | ||
8814 | ksymbol_event = (struct perf_ksymbol_event){ | |
8815 | .name = name, | |
8816 | .name_len = name_len, | |
8817 | .event_id = { | |
8818 | .header = { | |
8819 | .type = PERF_RECORD_KSYMBOL, | |
8820 | .size = sizeof(ksymbol_event.event_id) + | |
8821 | name_len, | |
8822 | }, | |
8823 | .addr = addr, | |
8824 | .len = len, | |
8825 | .ksym_type = ksym_type, | |
8826 | .flags = flags, | |
8827 | }, | |
8828 | }; | |
8829 | ||
8830 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8831 | return; | |
8832 | err: | |
8833 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8834 | } | |
8835 | ||
6ee52e2a SL |
8836 | /* |
8837 | * bpf program load/unload tracking | |
8838 | */ | |
8839 | ||
8840 | struct perf_bpf_event { | |
8841 | struct bpf_prog *prog; | |
8842 | struct { | |
8843 | struct perf_event_header header; | |
8844 | u16 type; | |
8845 | u16 flags; | |
8846 | u32 id; | |
8847 | u8 tag[BPF_TAG_SIZE]; | |
8848 | } event_id; | |
8849 | }; | |
8850 | ||
8851 | static int perf_event_bpf_match(struct perf_event *event) | |
8852 | { | |
8853 | return event->attr.bpf_event; | |
8854 | } | |
8855 | ||
8856 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8857 | { | |
8858 | struct perf_bpf_event *bpf_event = data; | |
8859 | struct perf_output_handle handle; | |
8860 | struct perf_sample_data sample; | |
8861 | int ret; | |
8862 | ||
8863 | if (!perf_event_bpf_match(event)) | |
8864 | return; | |
8865 | ||
8866 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8867 | &sample, event); | |
267fb273 | 8868 | ret = perf_output_begin(&handle, data, event, |
6ee52e2a SL |
8869 | bpf_event->event_id.header.size); |
8870 | if (ret) | |
8871 | return; | |
8872 | ||
8873 | perf_output_put(&handle, bpf_event->event_id); | |
8874 | perf_event__output_id_sample(event, &handle, &sample); | |
8875 | ||
8876 | perf_output_end(&handle); | |
8877 | } | |
8878 | ||
8879 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8880 | enum perf_bpf_event_type type) | |
8881 | { | |
8882 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8883 | int i; |
8884 | ||
8885 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8886 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8887 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8888 | prog->jited_len, unregister, |
8889 | prog->aux->ksym.name); | |
6ee52e2a SL |
8890 | } else { |
8891 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8892 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8893 | ||
6ee52e2a SL |
8894 | perf_event_ksymbol( |
8895 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8896 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8897 | subprog->jited_len, unregister, |
8898 | prog->aux->ksym.name); | |
6ee52e2a SL |
8899 | } |
8900 | } | |
8901 | } | |
8902 | ||
8903 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8904 | enum perf_bpf_event_type type, | |
8905 | u16 flags) | |
8906 | { | |
8907 | struct perf_bpf_event bpf_event; | |
8908 | ||
8909 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8910 | type >= PERF_BPF_EVENT_MAX) | |
8911 | return; | |
8912 | ||
8913 | switch (type) { | |
8914 | case PERF_BPF_EVENT_PROG_LOAD: | |
8915 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8916 | if (atomic_read(&nr_ksymbol_events)) | |
8917 | perf_event_bpf_emit_ksymbols(prog, type); | |
8918 | break; | |
8919 | default: | |
8920 | break; | |
8921 | } | |
8922 | ||
8923 | if (!atomic_read(&nr_bpf_events)) | |
8924 | return; | |
8925 | ||
8926 | bpf_event = (struct perf_bpf_event){ | |
8927 | .prog = prog, | |
8928 | .event_id = { | |
8929 | .header = { | |
8930 | .type = PERF_RECORD_BPF_EVENT, | |
8931 | .size = sizeof(bpf_event.event_id), | |
8932 | }, | |
8933 | .type = type, | |
8934 | .flags = flags, | |
8935 | .id = prog->aux->id, | |
8936 | }, | |
8937 | }; | |
8938 | ||
8939 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8940 | ||
8941 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8942 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8943 | } | |
8944 | ||
e17d43b9 AH |
8945 | struct perf_text_poke_event { |
8946 | const void *old_bytes; | |
8947 | const void *new_bytes; | |
8948 | size_t pad; | |
8949 | u16 old_len; | |
8950 | u16 new_len; | |
8951 | ||
8952 | struct { | |
8953 | struct perf_event_header header; | |
8954 | ||
8955 | u64 addr; | |
8956 | } event_id; | |
8957 | }; | |
8958 | ||
8959 | static int perf_event_text_poke_match(struct perf_event *event) | |
8960 | { | |
8961 | return event->attr.text_poke; | |
8962 | } | |
8963 | ||
8964 | static void perf_event_text_poke_output(struct perf_event *event, void *data) | |
8965 | { | |
8966 | struct perf_text_poke_event *text_poke_event = data; | |
8967 | struct perf_output_handle handle; | |
8968 | struct perf_sample_data sample; | |
8969 | u64 padding = 0; | |
8970 | int ret; | |
8971 | ||
8972 | if (!perf_event_text_poke_match(event)) | |
8973 | return; | |
8974 | ||
8975 | perf_event_header__init_id(&text_poke_event->event_id.header, &sample, event); | |
8976 | ||
267fb273 PZ |
8977 | ret = perf_output_begin(&handle, &sample, event, |
8978 | text_poke_event->event_id.header.size); | |
e17d43b9 AH |
8979 | if (ret) |
8980 | return; | |
8981 | ||
8982 | perf_output_put(&handle, text_poke_event->event_id); | |
8983 | perf_output_put(&handle, text_poke_event->old_len); | |
8984 | perf_output_put(&handle, text_poke_event->new_len); | |
8985 | ||
8986 | __output_copy(&handle, text_poke_event->old_bytes, text_poke_event->old_len); | |
8987 | __output_copy(&handle, text_poke_event->new_bytes, text_poke_event->new_len); | |
8988 | ||
8989 | if (text_poke_event->pad) | |
8990 | __output_copy(&handle, &padding, text_poke_event->pad); | |
8991 | ||
8992 | perf_event__output_id_sample(event, &handle, &sample); | |
8993 | ||
8994 | perf_output_end(&handle); | |
8995 | } | |
8996 | ||
8997 | void perf_event_text_poke(const void *addr, const void *old_bytes, | |
8998 | size_t old_len, const void *new_bytes, size_t new_len) | |
8999 | { | |
9000 | struct perf_text_poke_event text_poke_event; | |
9001 | size_t tot, pad; | |
9002 | ||
9003 | if (!atomic_read(&nr_text_poke_events)) | |
9004 | return; | |
9005 | ||
9006 | tot = sizeof(text_poke_event.old_len) + old_len; | |
9007 | tot += sizeof(text_poke_event.new_len) + new_len; | |
9008 | pad = ALIGN(tot, sizeof(u64)) - tot; | |
9009 | ||
9010 | text_poke_event = (struct perf_text_poke_event){ | |
9011 | .old_bytes = old_bytes, | |
9012 | .new_bytes = new_bytes, | |
9013 | .pad = pad, | |
9014 | .old_len = old_len, | |
9015 | .new_len = new_len, | |
9016 | .event_id = { | |
9017 | .header = { | |
9018 | .type = PERF_RECORD_TEXT_POKE, | |
9019 | .misc = PERF_RECORD_MISC_KERNEL, | |
9020 | .size = sizeof(text_poke_event.event_id) + tot + pad, | |
9021 | }, | |
9022 | .addr = (unsigned long)addr, | |
9023 | }, | |
9024 | }; | |
9025 | ||
9026 | perf_iterate_sb(perf_event_text_poke_output, &text_poke_event, NULL); | |
9027 | } | |
9028 | ||
8d4e6c4c AS |
9029 | void perf_event_itrace_started(struct perf_event *event) |
9030 | { | |
9031 | event->attach_state |= PERF_ATTACH_ITRACE; | |
9032 | } | |
9033 | ||
ec0d7729 AS |
9034 | static void perf_log_itrace_start(struct perf_event *event) |
9035 | { | |
9036 | struct perf_output_handle handle; | |
9037 | struct perf_sample_data sample; | |
9038 | struct perf_aux_event { | |
9039 | struct perf_event_header header; | |
9040 | u32 pid; | |
9041 | u32 tid; | |
9042 | } rec; | |
9043 | int ret; | |
9044 | ||
9045 | if (event->parent) | |
9046 | event = event->parent; | |
9047 | ||
9048 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 9049 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
9050 | return; |
9051 | ||
ec0d7729 AS |
9052 | rec.header.type = PERF_RECORD_ITRACE_START; |
9053 | rec.header.misc = 0; | |
9054 | rec.header.size = sizeof(rec); | |
9055 | rec.pid = perf_event_pid(event, current); | |
9056 | rec.tid = perf_event_tid(event, current); | |
9057 | ||
9058 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 9059 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
ec0d7729 AS |
9060 | |
9061 | if (ret) | |
9062 | return; | |
9063 | ||
9064 | perf_output_put(&handle, rec); | |
9065 | perf_event__output_id_sample(event, &handle, &sample); | |
9066 | ||
9067 | perf_output_end(&handle); | |
9068 | } | |
9069 | ||
475113d9 JO |
9070 | static int |
9071 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 9072 | { |
cdd6c482 | 9073 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 9074 | int ret = 0; |
475113d9 | 9075 | u64 seq; |
96398826 | 9076 | |
e050e3f0 SE |
9077 | seq = __this_cpu_read(perf_throttled_seq); |
9078 | if (seq != hwc->interrupts_seq) { | |
9079 | hwc->interrupts_seq = seq; | |
9080 | hwc->interrupts = 1; | |
9081 | } else { | |
9082 | hwc->interrupts++; | |
9083 | if (unlikely(throttle | |
9084 | && hwc->interrupts >= max_samples_per_tick)) { | |
9085 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 9086 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
9087 | hwc->interrupts = MAX_INTERRUPTS; |
9088 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
9089 | ret = 1; |
9090 | } | |
e050e3f0 | 9091 | } |
60db5e09 | 9092 | |
cdd6c482 | 9093 | if (event->attr.freq) { |
def0a9b2 | 9094 | u64 now = perf_clock(); |
abd50713 | 9095 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 9096 | |
abd50713 | 9097 | hwc->freq_time_stamp = now; |
bd2b5b12 | 9098 | |
abd50713 | 9099 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 9100 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
9101 | } |
9102 | ||
475113d9 JO |
9103 | return ret; |
9104 | } | |
9105 | ||
9106 | int perf_event_account_interrupt(struct perf_event *event) | |
9107 | { | |
9108 | return __perf_event_account_interrupt(event, 1); | |
9109 | } | |
9110 | ||
9111 | /* | |
9112 | * Generic event overflow handling, sampling. | |
9113 | */ | |
9114 | ||
9115 | static int __perf_event_overflow(struct perf_event *event, | |
9116 | int throttle, struct perf_sample_data *data, | |
9117 | struct pt_regs *regs) | |
9118 | { | |
9119 | int events = atomic_read(&event->event_limit); | |
9120 | int ret = 0; | |
9121 | ||
9122 | /* | |
9123 | * Non-sampling counters might still use the PMI to fold short | |
9124 | * hardware counters, ignore those. | |
9125 | */ | |
9126 | if (unlikely(!is_sampling_event(event))) | |
9127 | return 0; | |
9128 | ||
9129 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 9130 | |
2023b359 PZ |
9131 | /* |
9132 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 9133 | * events |
2023b359 PZ |
9134 | */ |
9135 | ||
cdd6c482 IM |
9136 | event->pending_kill = POLL_IN; |
9137 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 9138 | ret = 1; |
cdd6c482 | 9139 | event->pending_kill = POLL_HUP; |
97ba62b2 | 9140 | event->pending_addr = data->addr; |
5aab90ce JO |
9141 | |
9142 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
9143 | } |
9144 | ||
aa6a5f3c | 9145 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 9146 | |
fed66e2c | 9147 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
9148 | event->pending_wakeup = 1; |
9149 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
9150 | } |
9151 | ||
79f14641 | 9152 | return ret; |
f6c7d5fe PZ |
9153 | } |
9154 | ||
a8b0ca17 | 9155 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
9156 | struct perf_sample_data *data, |
9157 | struct pt_regs *regs) | |
850bc73f | 9158 | { |
a8b0ca17 | 9159 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
9160 | } |
9161 | ||
15dbf27c | 9162 | /* |
cdd6c482 | 9163 | * Generic software event infrastructure |
15dbf27c PZ |
9164 | */ |
9165 | ||
b28ab83c PZ |
9166 | struct swevent_htable { |
9167 | struct swevent_hlist *swevent_hlist; | |
9168 | struct mutex hlist_mutex; | |
9169 | int hlist_refcount; | |
9170 | ||
9171 | /* Recursion avoidance in each contexts */ | |
9172 | int recursion[PERF_NR_CONTEXTS]; | |
9173 | }; | |
9174 | ||
9175 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
9176 | ||
7b4b6658 | 9177 | /* |
cdd6c482 IM |
9178 | * We directly increment event->count and keep a second value in |
9179 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
9180 | * is kept in the range [-sample_period, 0] so that we can use the |
9181 | * sign as trigger. | |
9182 | */ | |
9183 | ||
ab573844 | 9184 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 9185 | { |
cdd6c482 | 9186 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
9187 | u64 period = hwc->last_period; |
9188 | u64 nr, offset; | |
9189 | s64 old, val; | |
9190 | ||
9191 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
9192 | |
9193 | again: | |
e7850595 | 9194 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
9195 | if (val < 0) |
9196 | return 0; | |
15dbf27c | 9197 | |
7b4b6658 PZ |
9198 | nr = div64_u64(period + val, period); |
9199 | offset = nr * period; | |
9200 | val -= offset; | |
e7850595 | 9201 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 9202 | goto again; |
15dbf27c | 9203 | |
7b4b6658 | 9204 | return nr; |
15dbf27c PZ |
9205 | } |
9206 | ||
0cff784a | 9207 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 9208 | struct perf_sample_data *data, |
5622f295 | 9209 | struct pt_regs *regs) |
15dbf27c | 9210 | { |
cdd6c482 | 9211 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 9212 | int throttle = 0; |
15dbf27c | 9213 | |
0cff784a PZ |
9214 | if (!overflow) |
9215 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 9216 | |
7b4b6658 PZ |
9217 | if (hwc->interrupts == MAX_INTERRUPTS) |
9218 | return; | |
15dbf27c | 9219 | |
7b4b6658 | 9220 | for (; overflow; overflow--) { |
a8b0ca17 | 9221 | if (__perf_event_overflow(event, throttle, |
5622f295 | 9222 | data, regs)) { |
7b4b6658 PZ |
9223 | /* |
9224 | * We inhibit the overflow from happening when | |
9225 | * hwc->interrupts == MAX_INTERRUPTS. | |
9226 | */ | |
9227 | break; | |
9228 | } | |
cf450a73 | 9229 | throttle = 1; |
7b4b6658 | 9230 | } |
15dbf27c PZ |
9231 | } |
9232 | ||
a4eaf7f1 | 9233 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 9234 | struct perf_sample_data *data, |
5622f295 | 9235 | struct pt_regs *regs) |
7b4b6658 | 9236 | { |
cdd6c482 | 9237 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 9238 | |
e7850595 | 9239 | local64_add(nr, &event->count); |
d6d020e9 | 9240 | |
0cff784a PZ |
9241 | if (!regs) |
9242 | return; | |
9243 | ||
6c7e550f | 9244 | if (!is_sampling_event(event)) |
7b4b6658 | 9245 | return; |
d6d020e9 | 9246 | |
5d81e5cf AV |
9247 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
9248 | data->period = nr; | |
9249 | return perf_swevent_overflow(event, 1, data, regs); | |
9250 | } else | |
9251 | data->period = event->hw.last_period; | |
9252 | ||
0cff784a | 9253 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 9254 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 9255 | |
e7850595 | 9256 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 9257 | return; |
df1a132b | 9258 | |
a8b0ca17 | 9259 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
9260 | } |
9261 | ||
f5ffe02e FW |
9262 | static int perf_exclude_event(struct perf_event *event, |
9263 | struct pt_regs *regs) | |
9264 | { | |
a4eaf7f1 | 9265 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 9266 | return 1; |
a4eaf7f1 | 9267 | |
f5ffe02e FW |
9268 | if (regs) { |
9269 | if (event->attr.exclude_user && user_mode(regs)) | |
9270 | return 1; | |
9271 | ||
9272 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
9273 | return 1; | |
9274 | } | |
9275 | ||
9276 | return 0; | |
9277 | } | |
9278 | ||
cdd6c482 | 9279 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 9280 | enum perf_type_id type, |
6fb2915d LZ |
9281 | u32 event_id, |
9282 | struct perf_sample_data *data, | |
9283 | struct pt_regs *regs) | |
15dbf27c | 9284 | { |
cdd6c482 | 9285 | if (event->attr.type != type) |
a21ca2ca | 9286 | return 0; |
f5ffe02e | 9287 | |
cdd6c482 | 9288 | if (event->attr.config != event_id) |
15dbf27c PZ |
9289 | return 0; |
9290 | ||
f5ffe02e FW |
9291 | if (perf_exclude_event(event, regs)) |
9292 | return 0; | |
15dbf27c PZ |
9293 | |
9294 | return 1; | |
9295 | } | |
9296 | ||
76e1d904 FW |
9297 | static inline u64 swevent_hash(u64 type, u32 event_id) |
9298 | { | |
9299 | u64 val = event_id | (type << 32); | |
9300 | ||
9301 | return hash_64(val, SWEVENT_HLIST_BITS); | |
9302 | } | |
9303 | ||
49f135ed FW |
9304 | static inline struct hlist_head * |
9305 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 9306 | { |
49f135ed FW |
9307 | u64 hash = swevent_hash(type, event_id); |
9308 | ||
9309 | return &hlist->heads[hash]; | |
9310 | } | |
76e1d904 | 9311 | |
49f135ed FW |
9312 | /* For the read side: events when they trigger */ |
9313 | static inline struct hlist_head * | |
b28ab83c | 9314 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
9315 | { |
9316 | struct swevent_hlist *hlist; | |
76e1d904 | 9317 | |
b28ab83c | 9318 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
9319 | if (!hlist) |
9320 | return NULL; | |
9321 | ||
49f135ed FW |
9322 | return __find_swevent_head(hlist, type, event_id); |
9323 | } | |
9324 | ||
9325 | /* For the event head insertion and removal in the hlist */ | |
9326 | static inline struct hlist_head * | |
b28ab83c | 9327 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
9328 | { |
9329 | struct swevent_hlist *hlist; | |
9330 | u32 event_id = event->attr.config; | |
9331 | u64 type = event->attr.type; | |
9332 | ||
9333 | /* | |
9334 | * Event scheduling is always serialized against hlist allocation | |
9335 | * and release. Which makes the protected version suitable here. | |
9336 | * The context lock guarantees that. | |
9337 | */ | |
b28ab83c | 9338 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
9339 | lockdep_is_held(&event->ctx->lock)); |
9340 | if (!hlist) | |
9341 | return NULL; | |
9342 | ||
9343 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
9344 | } |
9345 | ||
9346 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 9347 | u64 nr, |
76e1d904 FW |
9348 | struct perf_sample_data *data, |
9349 | struct pt_regs *regs) | |
15dbf27c | 9350 | { |
4a32fea9 | 9351 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9352 | struct perf_event *event; |
76e1d904 | 9353 | struct hlist_head *head; |
15dbf27c | 9354 | |
76e1d904 | 9355 | rcu_read_lock(); |
b28ab83c | 9356 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
9357 | if (!head) |
9358 | goto end; | |
9359 | ||
b67bfe0d | 9360 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 9361 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 9362 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 9363 | } |
76e1d904 FW |
9364 | end: |
9365 | rcu_read_unlock(); | |
15dbf27c PZ |
9366 | } |
9367 | ||
86038c5e PZI |
9368 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
9369 | ||
4ed7c92d | 9370 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 9371 | { |
4a32fea9 | 9372 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 9373 | |
b28ab83c | 9374 | return get_recursion_context(swhash->recursion); |
96f6d444 | 9375 | } |
645e8cc0 | 9376 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 9377 | |
98b5c2c6 | 9378 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 9379 | { |
4a32fea9 | 9380 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 9381 | |
b28ab83c | 9382 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 9383 | } |
15dbf27c | 9384 | |
86038c5e | 9385 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 9386 | { |
a4234bfc | 9387 | struct perf_sample_data data; |
4ed7c92d | 9388 | |
86038c5e | 9389 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 9390 | return; |
a4234bfc | 9391 | |
fd0d000b | 9392 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 9393 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
9394 | } |
9395 | ||
9396 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
9397 | { | |
9398 | int rctx; | |
9399 | ||
9400 | preempt_disable_notrace(); | |
9401 | rctx = perf_swevent_get_recursion_context(); | |
9402 | if (unlikely(rctx < 0)) | |
9403 | goto fail; | |
9404 | ||
9405 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
9406 | |
9407 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 9408 | fail: |
1c024eca | 9409 | preempt_enable_notrace(); |
b8e83514 PZ |
9410 | } |
9411 | ||
cdd6c482 | 9412 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 9413 | { |
15dbf27c PZ |
9414 | } |
9415 | ||
a4eaf7f1 | 9416 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 9417 | { |
4a32fea9 | 9418 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9419 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
9420 | struct hlist_head *head; |
9421 | ||
6c7e550f | 9422 | if (is_sampling_event(event)) { |
7b4b6658 | 9423 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 9424 | perf_swevent_set_period(event); |
7b4b6658 | 9425 | } |
76e1d904 | 9426 | |
a4eaf7f1 PZ |
9427 | hwc->state = !(flags & PERF_EF_START); |
9428 | ||
b28ab83c | 9429 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9430 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9431 | return -EINVAL; |
9432 | ||
9433 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9434 | perf_event_update_userpage(event); |
76e1d904 | 9435 | |
15dbf27c PZ |
9436 | return 0; |
9437 | } | |
9438 | ||
a4eaf7f1 | 9439 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9440 | { |
76e1d904 | 9441 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9442 | } |
9443 | ||
a4eaf7f1 | 9444 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9445 | { |
a4eaf7f1 | 9446 | event->hw.state = 0; |
d6d020e9 | 9447 | } |
aa9c4c0f | 9448 | |
a4eaf7f1 | 9449 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9450 | { |
a4eaf7f1 | 9451 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9452 | } |
9453 | ||
49f135ed FW |
9454 | /* Deref the hlist from the update side */ |
9455 | static inline struct swevent_hlist * | |
b28ab83c | 9456 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9457 | { |
b28ab83c PZ |
9458 | return rcu_dereference_protected(swhash->swevent_hlist, |
9459 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9460 | } |
9461 | ||
b28ab83c | 9462 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9463 | { |
b28ab83c | 9464 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9465 | |
49f135ed | 9466 | if (!hlist) |
76e1d904 FW |
9467 | return; |
9468 | ||
70691d4a | 9469 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9470 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9471 | } |
9472 | ||
3b364d7b | 9473 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9474 | { |
b28ab83c | 9475 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9476 | |
b28ab83c | 9477 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9478 | |
b28ab83c PZ |
9479 | if (!--swhash->hlist_refcount) |
9480 | swevent_hlist_release(swhash); | |
76e1d904 | 9481 | |
b28ab83c | 9482 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9483 | } |
9484 | ||
3b364d7b | 9485 | static void swevent_hlist_put(void) |
76e1d904 FW |
9486 | { |
9487 | int cpu; | |
9488 | ||
76e1d904 | 9489 | for_each_possible_cpu(cpu) |
3b364d7b | 9490 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9491 | } |
9492 | ||
3b364d7b | 9493 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9494 | { |
b28ab83c | 9495 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9496 | int err = 0; |
9497 | ||
b28ab83c | 9498 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9499 | if (!swevent_hlist_deref(swhash) && |
9500 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9501 | struct swevent_hlist *hlist; |
9502 | ||
9503 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9504 | if (!hlist) { | |
9505 | err = -ENOMEM; | |
9506 | goto exit; | |
9507 | } | |
b28ab83c | 9508 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9509 | } |
b28ab83c | 9510 | swhash->hlist_refcount++; |
9ed6060d | 9511 | exit: |
b28ab83c | 9512 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9513 | |
9514 | return err; | |
9515 | } | |
9516 | ||
3b364d7b | 9517 | static int swevent_hlist_get(void) |
76e1d904 | 9518 | { |
3b364d7b | 9519 | int err, cpu, failed_cpu; |
76e1d904 | 9520 | |
a63fbed7 | 9521 | mutex_lock(&pmus_lock); |
76e1d904 | 9522 | for_each_possible_cpu(cpu) { |
3b364d7b | 9523 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9524 | if (err) { |
9525 | failed_cpu = cpu; | |
9526 | goto fail; | |
9527 | } | |
9528 | } | |
a63fbed7 | 9529 | mutex_unlock(&pmus_lock); |
76e1d904 | 9530 | return 0; |
9ed6060d | 9531 | fail: |
76e1d904 FW |
9532 | for_each_possible_cpu(cpu) { |
9533 | if (cpu == failed_cpu) | |
9534 | break; | |
3b364d7b | 9535 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9536 | } |
a63fbed7 | 9537 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9538 | return err; |
9539 | } | |
9540 | ||
c5905afb | 9541 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9542 | |
b0a873eb PZ |
9543 | static void sw_perf_event_destroy(struct perf_event *event) |
9544 | { | |
9545 | u64 event_id = event->attr.config; | |
95476b64 | 9546 | |
b0a873eb PZ |
9547 | WARN_ON(event->parent); |
9548 | ||
c5905afb | 9549 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9550 | swevent_hlist_put(); |
b0a873eb PZ |
9551 | } |
9552 | ||
9553 | static int perf_swevent_init(struct perf_event *event) | |
9554 | { | |
8176cced | 9555 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9556 | |
9557 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9558 | return -ENOENT; | |
9559 | ||
2481c5fa SE |
9560 | /* |
9561 | * no branch sampling for software events | |
9562 | */ | |
9563 | if (has_branch_stack(event)) | |
9564 | return -EOPNOTSUPP; | |
9565 | ||
b0a873eb PZ |
9566 | switch (event_id) { |
9567 | case PERF_COUNT_SW_CPU_CLOCK: | |
9568 | case PERF_COUNT_SW_TASK_CLOCK: | |
9569 | return -ENOENT; | |
9570 | ||
9571 | default: | |
9572 | break; | |
9573 | } | |
9574 | ||
ce677831 | 9575 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9576 | return -ENOENT; |
9577 | ||
9578 | if (!event->parent) { | |
9579 | int err; | |
9580 | ||
3b364d7b | 9581 | err = swevent_hlist_get(); |
b0a873eb PZ |
9582 | if (err) |
9583 | return err; | |
9584 | ||
c5905afb | 9585 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9586 | event->destroy = sw_perf_event_destroy; |
9587 | } | |
9588 | ||
9589 | return 0; | |
9590 | } | |
9591 | ||
9592 | static struct pmu perf_swevent = { | |
89a1e187 | 9593 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9594 | |
34f43927 PZ |
9595 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9596 | ||
b0a873eb | 9597 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9598 | .add = perf_swevent_add, |
9599 | .del = perf_swevent_del, | |
9600 | .start = perf_swevent_start, | |
9601 | .stop = perf_swevent_stop, | |
1c024eca | 9602 | .read = perf_swevent_read, |
1c024eca PZ |
9603 | }; |
9604 | ||
b0a873eb PZ |
9605 | #ifdef CONFIG_EVENT_TRACING |
9606 | ||
1c024eca PZ |
9607 | static int perf_tp_filter_match(struct perf_event *event, |
9608 | struct perf_sample_data *data) | |
9609 | { | |
7e3f977e | 9610 | void *record = data->raw->frag.data; |
1c024eca | 9611 | |
b71b437e PZ |
9612 | /* only top level events have filters set */ |
9613 | if (event->parent) | |
9614 | event = event->parent; | |
9615 | ||
1c024eca PZ |
9616 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9617 | return 1; | |
9618 | return 0; | |
9619 | } | |
9620 | ||
9621 | static int perf_tp_event_match(struct perf_event *event, | |
9622 | struct perf_sample_data *data, | |
9623 | struct pt_regs *regs) | |
9624 | { | |
a0f7d0f7 FW |
9625 | if (event->hw.state & PERF_HES_STOPPED) |
9626 | return 0; | |
580d607c | 9627 | /* |
9fd2e48b | 9628 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9629 | */ |
9fd2e48b | 9630 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9631 | return 0; |
9632 | ||
9633 | if (!perf_tp_filter_match(event, data)) | |
9634 | return 0; | |
9635 | ||
9636 | return 1; | |
9637 | } | |
9638 | ||
85b67bcb AS |
9639 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9640 | struct trace_event_call *call, u64 count, | |
9641 | struct pt_regs *regs, struct hlist_head *head, | |
9642 | struct task_struct *task) | |
9643 | { | |
e87c6bc3 | 9644 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9645 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9646 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9647 | perf_swevent_put_recursion_context(rctx); |
9648 | return; | |
9649 | } | |
9650 | } | |
9651 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9652 | rctx, task); |
85b67bcb AS |
9653 | } |
9654 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9655 | ||
1e1dcd93 | 9656 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9657 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9658 | struct task_struct *task) |
95476b64 FW |
9659 | { |
9660 | struct perf_sample_data data; | |
8fd0fbbe | 9661 | struct perf_event *event; |
1c024eca | 9662 | |
95476b64 | 9663 | struct perf_raw_record raw = { |
7e3f977e DB |
9664 | .frag = { |
9665 | .size = entry_size, | |
9666 | .data = record, | |
9667 | }, | |
95476b64 FW |
9668 | }; |
9669 | ||
1e1dcd93 | 9670 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9671 | data.raw = &raw; |
9672 | ||
1e1dcd93 AS |
9673 | perf_trace_buf_update(record, event_type); |
9674 | ||
8fd0fbbe | 9675 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9676 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9677 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9678 | } |
ecc55f84 | 9679 | |
e6dab5ff AV |
9680 | /* |
9681 | * If we got specified a target task, also iterate its context and | |
9682 | * deliver this event there too. | |
9683 | */ | |
9684 | if (task && task != current) { | |
9685 | struct perf_event_context *ctx; | |
9686 | struct trace_entry *entry = record; | |
9687 | ||
9688 | rcu_read_lock(); | |
9689 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9690 | if (!ctx) | |
9691 | goto unlock; | |
9692 | ||
9693 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9694 | if (event->cpu != smp_processor_id()) |
9695 | continue; | |
e6dab5ff AV |
9696 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9697 | continue; | |
9698 | if (event->attr.config != entry->type) | |
9699 | continue; | |
9700 | if (perf_tp_event_match(event, &data, regs)) | |
9701 | perf_swevent_event(event, count, &data, regs); | |
9702 | } | |
9703 | unlock: | |
9704 | rcu_read_unlock(); | |
9705 | } | |
9706 | ||
ecc55f84 | 9707 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9708 | } |
9709 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9710 | ||
cdd6c482 | 9711 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9712 | { |
1c024eca | 9713 | perf_trace_destroy(event); |
e077df4f PZ |
9714 | } |
9715 | ||
b0a873eb | 9716 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9717 | { |
76e1d904 FW |
9718 | int err; |
9719 | ||
b0a873eb PZ |
9720 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9721 | return -ENOENT; | |
9722 | ||
2481c5fa SE |
9723 | /* |
9724 | * no branch sampling for tracepoint events | |
9725 | */ | |
9726 | if (has_branch_stack(event)) | |
9727 | return -EOPNOTSUPP; | |
9728 | ||
1c024eca PZ |
9729 | err = perf_trace_init(event); |
9730 | if (err) | |
b0a873eb | 9731 | return err; |
e077df4f | 9732 | |
cdd6c482 | 9733 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9734 | |
b0a873eb PZ |
9735 | return 0; |
9736 | } | |
9737 | ||
9738 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9739 | .task_ctx_nr = perf_sw_context, |
9740 | ||
b0a873eb | 9741 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9742 | .add = perf_trace_add, |
9743 | .del = perf_trace_del, | |
9744 | .start = perf_swevent_start, | |
9745 | .stop = perf_swevent_stop, | |
b0a873eb | 9746 | .read = perf_swevent_read, |
b0a873eb PZ |
9747 | }; |
9748 | ||
33ea4b24 | 9749 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9750 | /* |
9751 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9752 | * The flags should match following PMU_FORMAT_ATTR(). | |
9753 | * | |
9754 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9755 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9756 | * |
9757 | * The following values specify a reference counter (or semaphore in the | |
9758 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9759 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9760 | * | |
9761 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9762 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9763 | */ |
9764 | enum perf_probe_config { | |
9765 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9766 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9767 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9768 | }; |
9769 | ||
9770 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9771 | #endif |
e12f03d7 | 9772 | |
a6ca88b2 SL |
9773 | #ifdef CONFIG_KPROBE_EVENTS |
9774 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9775 | &format_attr_retprobe.attr, |
9776 | NULL, | |
9777 | }; | |
9778 | ||
a6ca88b2 | 9779 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9780 | .name = "format", |
a6ca88b2 | 9781 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9782 | }; |
9783 | ||
a6ca88b2 SL |
9784 | static const struct attribute_group *kprobe_attr_groups[] = { |
9785 | &kprobe_format_group, | |
e12f03d7 SL |
9786 | NULL, |
9787 | }; | |
9788 | ||
9789 | static int perf_kprobe_event_init(struct perf_event *event); | |
9790 | static struct pmu perf_kprobe = { | |
9791 | .task_ctx_nr = perf_sw_context, | |
9792 | .event_init = perf_kprobe_event_init, | |
9793 | .add = perf_trace_add, | |
9794 | .del = perf_trace_del, | |
9795 | .start = perf_swevent_start, | |
9796 | .stop = perf_swevent_stop, | |
9797 | .read = perf_swevent_read, | |
a6ca88b2 | 9798 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9799 | }; |
9800 | ||
9801 | static int perf_kprobe_event_init(struct perf_event *event) | |
9802 | { | |
9803 | int err; | |
9804 | bool is_retprobe; | |
9805 | ||
9806 | if (event->attr.type != perf_kprobe.type) | |
9807 | return -ENOENT; | |
32e6e967 | 9808 | |
c9e0924e | 9809 | if (!perfmon_capable()) |
32e6e967 SL |
9810 | return -EACCES; |
9811 | ||
e12f03d7 SL |
9812 | /* |
9813 | * no branch sampling for probe events | |
9814 | */ | |
9815 | if (has_branch_stack(event)) | |
9816 | return -EOPNOTSUPP; | |
9817 | ||
9818 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9819 | err = perf_kprobe_init(event, is_retprobe); | |
9820 | if (err) | |
9821 | return err; | |
9822 | ||
9823 | event->destroy = perf_kprobe_destroy; | |
9824 | ||
9825 | return 0; | |
9826 | } | |
9827 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9828 | ||
33ea4b24 | 9829 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9830 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9831 | ||
9832 | static struct attribute *uprobe_attrs[] = { | |
9833 | &format_attr_retprobe.attr, | |
9834 | &format_attr_ref_ctr_offset.attr, | |
9835 | NULL, | |
9836 | }; | |
9837 | ||
9838 | static struct attribute_group uprobe_format_group = { | |
9839 | .name = "format", | |
9840 | .attrs = uprobe_attrs, | |
9841 | }; | |
9842 | ||
9843 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9844 | &uprobe_format_group, | |
9845 | NULL, | |
9846 | }; | |
9847 | ||
33ea4b24 SL |
9848 | static int perf_uprobe_event_init(struct perf_event *event); |
9849 | static struct pmu perf_uprobe = { | |
9850 | .task_ctx_nr = perf_sw_context, | |
9851 | .event_init = perf_uprobe_event_init, | |
9852 | .add = perf_trace_add, | |
9853 | .del = perf_trace_del, | |
9854 | .start = perf_swevent_start, | |
9855 | .stop = perf_swevent_stop, | |
9856 | .read = perf_swevent_read, | |
a6ca88b2 | 9857 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9858 | }; |
9859 | ||
9860 | static int perf_uprobe_event_init(struct perf_event *event) | |
9861 | { | |
9862 | int err; | |
a6ca88b2 | 9863 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9864 | bool is_retprobe; |
9865 | ||
9866 | if (event->attr.type != perf_uprobe.type) | |
9867 | return -ENOENT; | |
32e6e967 | 9868 | |
c9e0924e | 9869 | if (!perfmon_capable()) |
32e6e967 SL |
9870 | return -EACCES; |
9871 | ||
33ea4b24 SL |
9872 | /* |
9873 | * no branch sampling for probe events | |
9874 | */ | |
9875 | if (has_branch_stack(event)) | |
9876 | return -EOPNOTSUPP; | |
9877 | ||
9878 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9879 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9880 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9881 | if (err) |
9882 | return err; | |
9883 | ||
9884 | event->destroy = perf_uprobe_destroy; | |
9885 | ||
9886 | return 0; | |
9887 | } | |
9888 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9889 | ||
b0a873eb PZ |
9890 | static inline void perf_tp_register(void) |
9891 | { | |
2e80a82a | 9892 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9893 | #ifdef CONFIG_KPROBE_EVENTS |
9894 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9895 | #endif | |
33ea4b24 SL |
9896 | #ifdef CONFIG_UPROBE_EVENTS |
9897 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9898 | #endif | |
e077df4f | 9899 | } |
6fb2915d | 9900 | |
6fb2915d LZ |
9901 | static void perf_event_free_filter(struct perf_event *event) |
9902 | { | |
9903 | ftrace_profile_free_filter(event); | |
9904 | } | |
9905 | ||
aa6a5f3c AS |
9906 | #ifdef CONFIG_BPF_SYSCALL |
9907 | static void bpf_overflow_handler(struct perf_event *event, | |
9908 | struct perf_sample_data *data, | |
9909 | struct pt_regs *regs) | |
9910 | { | |
9911 | struct bpf_perf_event_data_kern ctx = { | |
9912 | .data = data, | |
7d9285e8 | 9913 | .event = event, |
aa6a5f3c AS |
9914 | }; |
9915 | int ret = 0; | |
9916 | ||
c895f6f7 | 9917 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9918 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9919 | goto out; | |
9920 | rcu_read_lock(); | |
88575199 | 9921 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9922 | rcu_read_unlock(); |
9923 | out: | |
9924 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9925 | if (!ret) |
9926 | return; | |
9927 | ||
9928 | event->orig_overflow_handler(event, data, regs); | |
9929 | } | |
9930 | ||
9931 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9932 | { | |
9933 | struct bpf_prog *prog; | |
9934 | ||
9935 | if (event->overflow_handler_context) | |
9936 | /* hw breakpoint or kernel counter */ | |
9937 | return -EINVAL; | |
9938 | ||
9939 | if (event->prog) | |
9940 | return -EEXIST; | |
9941 | ||
9942 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9943 | if (IS_ERR(prog)) | |
9944 | return PTR_ERR(prog); | |
9945 | ||
5d99cb2c SL |
9946 | if (event->attr.precise_ip && |
9947 | prog->call_get_stack && | |
9948 | (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY) || | |
9949 | event->attr.exclude_callchain_kernel || | |
9950 | event->attr.exclude_callchain_user)) { | |
9951 | /* | |
9952 | * On perf_event with precise_ip, calling bpf_get_stack() | |
9953 | * may trigger unwinder warnings and occasional crashes. | |
9954 | * bpf_get_[stack|stackid] works around this issue by using | |
9955 | * callchain attached to perf_sample_data. If the | |
9956 | * perf_event does not full (kernel and user) callchain | |
9957 | * attached to perf_sample_data, do not allow attaching BPF | |
9958 | * program that calls bpf_get_[stack|stackid]. | |
9959 | */ | |
9960 | bpf_prog_put(prog); | |
9961 | return -EPROTO; | |
9962 | } | |
9963 | ||
aa6a5f3c AS |
9964 | event->prog = prog; |
9965 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9966 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9967 | return 0; | |
9968 | } | |
9969 | ||
9970 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9971 | { | |
9972 | struct bpf_prog *prog = event->prog; | |
9973 | ||
9974 | if (!prog) | |
9975 | return; | |
9976 | ||
9977 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9978 | event->prog = NULL; | |
9979 | bpf_prog_put(prog); | |
9980 | } | |
9981 | #else | |
9982 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9983 | { | |
9984 | return -EOPNOTSUPP; | |
9985 | } | |
9986 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9987 | { | |
9988 | } | |
9989 | #endif | |
9990 | ||
e12f03d7 SL |
9991 | /* |
9992 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9993 | * with perf_event_open() | |
9994 | */ | |
9995 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9996 | { | |
9997 | if (event->pmu == &perf_tracepoint) | |
9998 | return true; | |
9999 | #ifdef CONFIG_KPROBE_EVENTS | |
10000 | if (event->pmu == &perf_kprobe) | |
10001 | return true; | |
33ea4b24 SL |
10002 | #endif |
10003 | #ifdef CONFIG_UPROBE_EVENTS | |
10004 | if (event->pmu == &perf_uprobe) | |
10005 | return true; | |
e12f03d7 SL |
10006 | #endif |
10007 | return false; | |
10008 | } | |
10009 | ||
2541517c AS |
10010 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
10011 | { | |
cf5f5cea | 10012 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 10013 | struct bpf_prog *prog; |
e87c6bc3 | 10014 | int ret; |
2541517c | 10015 | |
e12f03d7 | 10016 | if (!perf_event_is_tracing(event)) |
f91840a3 | 10017 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 10018 | |
98b5c2c6 AS |
10019 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
10020 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
10021 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
10022 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 10023 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
10024 | return -EINVAL; |
10025 | ||
10026 | prog = bpf_prog_get(prog_fd); | |
10027 | if (IS_ERR(prog)) | |
10028 | return PTR_ERR(prog); | |
10029 | ||
98b5c2c6 | 10030 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
10031 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
10032 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
10033 | /* valid fd, but invalid bpf program type */ |
10034 | bpf_prog_put(prog); | |
10035 | return -EINVAL; | |
10036 | } | |
10037 | ||
9802d865 JB |
10038 | /* Kprobe override only works for kprobes, not uprobes. */ |
10039 | if (prog->kprobe_override && | |
10040 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
10041 | bpf_prog_put(prog); | |
10042 | return -EINVAL; | |
10043 | } | |
10044 | ||
cf5f5cea | 10045 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
10046 | int off = trace_event_get_offsets(event->tp_event); |
10047 | ||
10048 | if (prog->aux->max_ctx_offset > off) { | |
10049 | bpf_prog_put(prog); | |
10050 | return -EACCES; | |
10051 | } | |
10052 | } | |
2541517c | 10053 | |
e87c6bc3 YS |
10054 | ret = perf_event_attach_bpf_prog(event, prog); |
10055 | if (ret) | |
10056 | bpf_prog_put(prog); | |
10057 | return ret; | |
2541517c AS |
10058 | } |
10059 | ||
10060 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
10061 | { | |
e12f03d7 | 10062 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 10063 | perf_event_free_bpf_handler(event); |
2541517c | 10064 | return; |
2541517c | 10065 | } |
e87c6bc3 | 10066 | perf_event_detach_bpf_prog(event); |
2541517c AS |
10067 | } |
10068 | ||
e077df4f | 10069 | #else |
6fb2915d | 10070 | |
b0a873eb | 10071 | static inline void perf_tp_register(void) |
e077df4f | 10072 | { |
e077df4f | 10073 | } |
6fb2915d | 10074 | |
6fb2915d LZ |
10075 | static void perf_event_free_filter(struct perf_event *event) |
10076 | { | |
10077 | } | |
10078 | ||
2541517c AS |
10079 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
10080 | { | |
10081 | return -ENOENT; | |
10082 | } | |
10083 | ||
10084 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
10085 | { | |
10086 | } | |
07b139c8 | 10087 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 10088 | |
24f1e32c | 10089 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 10090 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 10091 | { |
f5ffe02e FW |
10092 | struct perf_sample_data sample; |
10093 | struct pt_regs *regs = data; | |
10094 | ||
fd0d000b | 10095 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 10096 | |
a4eaf7f1 | 10097 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 10098 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
10099 | } |
10100 | #endif | |
10101 | ||
375637bc AS |
10102 | /* |
10103 | * Allocate a new address filter | |
10104 | */ | |
10105 | static struct perf_addr_filter * | |
10106 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
10107 | { | |
10108 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
10109 | struct perf_addr_filter *filter; | |
10110 | ||
10111 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
10112 | if (!filter) | |
10113 | return NULL; | |
10114 | ||
10115 | INIT_LIST_HEAD(&filter->entry); | |
10116 | list_add_tail(&filter->entry, filters); | |
10117 | ||
10118 | return filter; | |
10119 | } | |
10120 | ||
10121 | static void free_filters_list(struct list_head *filters) | |
10122 | { | |
10123 | struct perf_addr_filter *filter, *iter; | |
10124 | ||
10125 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 10126 | path_put(&filter->path); |
375637bc AS |
10127 | list_del(&filter->entry); |
10128 | kfree(filter); | |
10129 | } | |
10130 | } | |
10131 | ||
10132 | /* | |
10133 | * Free existing address filters and optionally install new ones | |
10134 | */ | |
10135 | static void perf_addr_filters_splice(struct perf_event *event, | |
10136 | struct list_head *head) | |
10137 | { | |
10138 | unsigned long flags; | |
10139 | LIST_HEAD(list); | |
10140 | ||
10141 | if (!has_addr_filter(event)) | |
10142 | return; | |
10143 | ||
10144 | /* don't bother with children, they don't have their own filters */ | |
10145 | if (event->parent) | |
10146 | return; | |
10147 | ||
10148 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
10149 | ||
10150 | list_splice_init(&event->addr_filters.list, &list); | |
10151 | if (head) | |
10152 | list_splice(head, &event->addr_filters.list); | |
10153 | ||
10154 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
10155 | ||
10156 | free_filters_list(&list); | |
10157 | } | |
10158 | ||
10159 | /* | |
10160 | * Scan through mm's vmas and see if one of them matches the | |
10161 | * @filter; if so, adjust filter's address range. | |
c1e8d7c6 | 10162 | * Called with mm::mmap_lock down for reading. |
375637bc | 10163 | */ |
c60f83b8 AS |
10164 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
10165 | struct mm_struct *mm, | |
10166 | struct perf_addr_filter_range *fr) | |
375637bc AS |
10167 | { |
10168 | struct vm_area_struct *vma; | |
10169 | ||
10170 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 10171 | if (!vma->vm_file) |
375637bc AS |
10172 | continue; |
10173 | ||
c60f83b8 AS |
10174 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
10175 | return; | |
375637bc | 10176 | } |
375637bc AS |
10177 | } |
10178 | ||
10179 | /* | |
10180 | * Update event's address range filters based on the | |
10181 | * task's existing mappings, if any. | |
10182 | */ | |
10183 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
10184 | { | |
10185 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10186 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
10187 | struct perf_addr_filter *filter; | |
10188 | struct mm_struct *mm = NULL; | |
10189 | unsigned int count = 0; | |
10190 | unsigned long flags; | |
10191 | ||
10192 | /* | |
10193 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
10194 | * will stop on the parent's child_mutex that our caller is also holding | |
10195 | */ | |
10196 | if (task == TASK_TOMBSTONE) | |
10197 | return; | |
10198 | ||
52a44f83 AS |
10199 | if (ifh->nr_file_filters) { |
10200 | mm = get_task_mm(event->ctx->task); | |
10201 | if (!mm) | |
10202 | goto restart; | |
375637bc | 10203 | |
d8ed45c5 | 10204 | mmap_read_lock(mm); |
52a44f83 | 10205 | } |
375637bc AS |
10206 | |
10207 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
10208 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
10209 | if (filter->path.dentry) { |
10210 | /* | |
10211 | * Adjust base offset if the filter is associated to a | |
10212 | * binary that needs to be mapped: | |
10213 | */ | |
10214 | event->addr_filter_ranges[count].start = 0; | |
10215 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 10216 | |
c60f83b8 | 10217 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
10218 | } else { |
10219 | event->addr_filter_ranges[count].start = filter->offset; | |
10220 | event->addr_filter_ranges[count].size = filter->size; | |
10221 | } | |
375637bc AS |
10222 | |
10223 | count++; | |
10224 | } | |
10225 | ||
10226 | event->addr_filters_gen++; | |
10227 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
10228 | ||
52a44f83 | 10229 | if (ifh->nr_file_filters) { |
d8ed45c5 | 10230 | mmap_read_unlock(mm); |
375637bc | 10231 | |
52a44f83 AS |
10232 | mmput(mm); |
10233 | } | |
375637bc AS |
10234 | |
10235 | restart: | |
767ae086 | 10236 | perf_event_stop(event, 1); |
375637bc AS |
10237 | } |
10238 | ||
10239 | /* | |
10240 | * Address range filtering: limiting the data to certain | |
10241 | * instruction address ranges. Filters are ioctl()ed to us from | |
10242 | * userspace as ascii strings. | |
10243 | * | |
10244 | * Filter string format: | |
10245 | * | |
10246 | * ACTION RANGE_SPEC | |
10247 | * where ACTION is one of the | |
10248 | * * "filter": limit the trace to this region | |
10249 | * * "start": start tracing from this address | |
10250 | * * "stop": stop tracing at this address/region; | |
10251 | * RANGE_SPEC is | |
10252 | * * for kernel addresses: <start address>[/<size>] | |
10253 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
10254 | * | |
6ed70cf3 AS |
10255 | * if <size> is not specified or is zero, the range is treated as a single |
10256 | * address; not valid for ACTION=="filter". | |
375637bc AS |
10257 | */ |
10258 | enum { | |
e96271f3 | 10259 | IF_ACT_NONE = -1, |
375637bc AS |
10260 | IF_ACT_FILTER, |
10261 | IF_ACT_START, | |
10262 | IF_ACT_STOP, | |
10263 | IF_SRC_FILE, | |
10264 | IF_SRC_KERNEL, | |
10265 | IF_SRC_FILEADDR, | |
10266 | IF_SRC_KERNELADDR, | |
10267 | }; | |
10268 | ||
10269 | enum { | |
10270 | IF_STATE_ACTION = 0, | |
10271 | IF_STATE_SOURCE, | |
10272 | IF_STATE_END, | |
10273 | }; | |
10274 | ||
10275 | static const match_table_t if_tokens = { | |
10276 | { IF_ACT_FILTER, "filter" }, | |
10277 | { IF_ACT_START, "start" }, | |
10278 | { IF_ACT_STOP, "stop" }, | |
10279 | { IF_SRC_FILE, "%u/%u@%s" }, | |
10280 | { IF_SRC_KERNEL, "%u/%u" }, | |
10281 | { IF_SRC_FILEADDR, "%u@%s" }, | |
10282 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 10283 | { IF_ACT_NONE, NULL }, |
375637bc AS |
10284 | }; |
10285 | ||
10286 | /* | |
10287 | * Address filter string parser | |
10288 | */ | |
10289 | static int | |
10290 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
10291 | struct list_head *filters) | |
10292 | { | |
10293 | struct perf_addr_filter *filter = NULL; | |
10294 | char *start, *orig, *filename = NULL; | |
375637bc AS |
10295 | substring_t args[MAX_OPT_ARGS]; |
10296 | int state = IF_STATE_ACTION, token; | |
10297 | unsigned int kernel = 0; | |
10298 | int ret = -EINVAL; | |
10299 | ||
10300 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
10301 | if (!fstr) | |
10302 | return -ENOMEM; | |
10303 | ||
10304 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
10305 | static const enum perf_addr_filter_action_t actions[] = { |
10306 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
10307 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
10308 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
10309 | }; | |
375637bc AS |
10310 | ret = -EINVAL; |
10311 | ||
10312 | if (!*start) | |
10313 | continue; | |
10314 | ||
10315 | /* filter definition begins */ | |
10316 | if (state == IF_STATE_ACTION) { | |
10317 | filter = perf_addr_filter_new(event, filters); | |
10318 | if (!filter) | |
10319 | goto fail; | |
10320 | } | |
10321 | ||
10322 | token = match_token(start, if_tokens, args); | |
10323 | switch (token) { | |
10324 | case IF_ACT_FILTER: | |
10325 | case IF_ACT_START: | |
375637bc AS |
10326 | case IF_ACT_STOP: |
10327 | if (state != IF_STATE_ACTION) | |
10328 | goto fail; | |
10329 | ||
6ed70cf3 | 10330 | filter->action = actions[token]; |
375637bc AS |
10331 | state = IF_STATE_SOURCE; |
10332 | break; | |
10333 | ||
10334 | case IF_SRC_KERNELADDR: | |
10335 | case IF_SRC_KERNEL: | |
10336 | kernel = 1; | |
df561f66 | 10337 | fallthrough; |
375637bc AS |
10338 | |
10339 | case IF_SRC_FILEADDR: | |
10340 | case IF_SRC_FILE: | |
10341 | if (state != IF_STATE_SOURCE) | |
10342 | goto fail; | |
10343 | ||
375637bc AS |
10344 | *args[0].to = 0; |
10345 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
10346 | if (ret) | |
10347 | goto fail; | |
10348 | ||
6ed70cf3 | 10349 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
10350 | *args[1].to = 0; |
10351 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
10352 | if (ret) | |
10353 | goto fail; | |
10354 | } | |
10355 | ||
4059ffd0 | 10356 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 10357 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 | 10358 | |
7bdb157c | 10359 | kfree(filename); |
4059ffd0 | 10360 | filename = match_strdup(&args[fpos]); |
375637bc AS |
10361 | if (!filename) { |
10362 | ret = -ENOMEM; | |
10363 | goto fail; | |
10364 | } | |
10365 | } | |
10366 | ||
10367 | state = IF_STATE_END; | |
10368 | break; | |
10369 | ||
10370 | default: | |
10371 | goto fail; | |
10372 | } | |
10373 | ||
10374 | /* | |
10375 | * Filter definition is fully parsed, validate and install it. | |
10376 | * Make sure that it doesn't contradict itself or the event's | |
10377 | * attribute. | |
10378 | */ | |
10379 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 10380 | ret = -EINVAL; |
375637bc AS |
10381 | if (kernel && event->attr.exclude_kernel) |
10382 | goto fail; | |
10383 | ||
6ed70cf3 AS |
10384 | /* |
10385 | * ACTION "filter" must have a non-zero length region | |
10386 | * specified. | |
10387 | */ | |
10388 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
10389 | !filter->size) | |
10390 | goto fail; | |
10391 | ||
375637bc AS |
10392 | if (!kernel) { |
10393 | if (!filename) | |
10394 | goto fail; | |
10395 | ||
6ce77bfd AS |
10396 | /* |
10397 | * For now, we only support file-based filters | |
10398 | * in per-task events; doing so for CPU-wide | |
10399 | * events requires additional context switching | |
10400 | * trickery, since same object code will be | |
10401 | * mapped at different virtual addresses in | |
10402 | * different processes. | |
10403 | */ | |
10404 | ret = -EOPNOTSUPP; | |
10405 | if (!event->ctx->task) | |
7bdb157c | 10406 | goto fail; |
6ce77bfd | 10407 | |
375637bc | 10408 | /* look up the path and grab its inode */ |
9511bce9 SL |
10409 | ret = kern_path(filename, LOOKUP_FOLLOW, |
10410 | &filter->path); | |
375637bc | 10411 | if (ret) |
7bdb157c | 10412 | goto fail; |
375637bc AS |
10413 | |
10414 | ret = -EINVAL; | |
9511bce9 SL |
10415 | if (!filter->path.dentry || |
10416 | !S_ISREG(d_inode(filter->path.dentry) | |
10417 | ->i_mode)) | |
375637bc | 10418 | goto fail; |
6ce77bfd AS |
10419 | |
10420 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
10421 | } |
10422 | ||
10423 | /* ready to consume more filters */ | |
10424 | state = IF_STATE_ACTION; | |
10425 | filter = NULL; | |
10426 | } | |
10427 | } | |
10428 | ||
10429 | if (state != IF_STATE_ACTION) | |
10430 | goto fail; | |
10431 | ||
7bdb157c | 10432 | kfree(filename); |
375637bc AS |
10433 | kfree(orig); |
10434 | ||
10435 | return 0; | |
10436 | ||
375637bc | 10437 | fail: |
7bdb157c | 10438 | kfree(filename); |
375637bc AS |
10439 | free_filters_list(filters); |
10440 | kfree(orig); | |
10441 | ||
10442 | return ret; | |
10443 | } | |
10444 | ||
10445 | static int | |
10446 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10447 | { | |
10448 | LIST_HEAD(filters); | |
10449 | int ret; | |
10450 | ||
10451 | /* | |
10452 | * Since this is called in perf_ioctl() path, we're already holding | |
10453 | * ctx::mutex. | |
10454 | */ | |
10455 | lockdep_assert_held(&event->ctx->mutex); | |
10456 | ||
10457 | if (WARN_ON_ONCE(event->parent)) | |
10458 | return -EINVAL; | |
10459 | ||
375637bc AS |
10460 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10461 | if (ret) | |
6ce77bfd | 10462 | goto fail_clear_files; |
375637bc AS |
10463 | |
10464 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10465 | if (ret) |
10466 | goto fail_free_filters; | |
375637bc AS |
10467 | |
10468 | /* remove existing filters, if any */ | |
10469 | perf_addr_filters_splice(event, &filters); | |
10470 | ||
10471 | /* install new filters */ | |
10472 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10473 | ||
6ce77bfd AS |
10474 | return ret; |
10475 | ||
10476 | fail_free_filters: | |
10477 | free_filters_list(&filters); | |
10478 | ||
10479 | fail_clear_files: | |
10480 | event->addr_filters.nr_file_filters = 0; | |
10481 | ||
375637bc AS |
10482 | return ret; |
10483 | } | |
10484 | ||
c796bbbe AS |
10485 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10486 | { | |
c796bbbe | 10487 | int ret = -EINVAL; |
e12f03d7 | 10488 | char *filter_str; |
c796bbbe AS |
10489 | |
10490 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10491 | if (IS_ERR(filter_str)) | |
10492 | return PTR_ERR(filter_str); | |
10493 | ||
e12f03d7 SL |
10494 | #ifdef CONFIG_EVENT_TRACING |
10495 | if (perf_event_is_tracing(event)) { | |
10496 | struct perf_event_context *ctx = event->ctx; | |
10497 | ||
10498 | /* | |
10499 | * Beware, here be dragons!! | |
10500 | * | |
10501 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10502 | * the tracepoint stuff does not actually need it. So | |
10503 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10504 | * already have a reference on ctx. | |
10505 | * | |
10506 | * This can result in event getting moved to a different ctx, | |
10507 | * but that does not affect the tracepoint state. | |
10508 | */ | |
10509 | mutex_unlock(&ctx->mutex); | |
10510 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10511 | mutex_lock(&ctx->mutex); | |
10512 | } else | |
10513 | #endif | |
10514 | if (has_addr_filter(event)) | |
375637bc | 10515 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10516 | |
10517 | kfree(filter_str); | |
10518 | return ret; | |
10519 | } | |
10520 | ||
b0a873eb PZ |
10521 | /* |
10522 | * hrtimer based swevent callback | |
10523 | */ | |
f29ac756 | 10524 | |
b0a873eb | 10525 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10526 | { |
b0a873eb PZ |
10527 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10528 | struct perf_sample_data data; | |
10529 | struct pt_regs *regs; | |
10530 | struct perf_event *event; | |
10531 | u64 period; | |
f29ac756 | 10532 | |
b0a873eb | 10533 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10534 | |
10535 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10536 | return HRTIMER_NORESTART; | |
10537 | ||
b0a873eb | 10538 | event->pmu->read(event); |
f344011c | 10539 | |
fd0d000b | 10540 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10541 | regs = get_irq_regs(); |
10542 | ||
10543 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10544 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10545 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10546 | ret = HRTIMER_NORESTART; |
10547 | } | |
24f1e32c | 10548 | |
b0a873eb PZ |
10549 | period = max_t(u64, 10000, event->hw.sample_period); |
10550 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10551 | |
b0a873eb | 10552 | return ret; |
f29ac756 PZ |
10553 | } |
10554 | ||
b0a873eb | 10555 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10556 | { |
b0a873eb | 10557 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10558 | s64 period; |
10559 | ||
10560 | if (!is_sampling_event(event)) | |
10561 | return; | |
f5ffe02e | 10562 | |
5d508e82 FBH |
10563 | period = local64_read(&hwc->period_left); |
10564 | if (period) { | |
10565 | if (period < 0) | |
10566 | period = 10000; | |
fa407f35 | 10567 | |
5d508e82 FBH |
10568 | local64_set(&hwc->period_left, 0); |
10569 | } else { | |
10570 | period = max_t(u64, 10000, hwc->sample_period); | |
10571 | } | |
3497d206 | 10572 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10573 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10574 | } |
b0a873eb PZ |
10575 | |
10576 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10577 | { |
b0a873eb PZ |
10578 | struct hw_perf_event *hwc = &event->hw; |
10579 | ||
6c7e550f | 10580 | if (is_sampling_event(event)) { |
b0a873eb | 10581 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10582 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10583 | |
10584 | hrtimer_cancel(&hwc->hrtimer); | |
10585 | } | |
24f1e32c FW |
10586 | } |
10587 | ||
ba3dd36c PZ |
10588 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10589 | { | |
10590 | struct hw_perf_event *hwc = &event->hw; | |
10591 | ||
10592 | if (!is_sampling_event(event)) | |
10593 | return; | |
10594 | ||
30f9028b | 10595 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10596 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10597 | ||
10598 | /* | |
10599 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10600 | * mapping and avoid the whole period adjust feedback stuff. | |
10601 | */ | |
10602 | if (event->attr.freq) { | |
10603 | long freq = event->attr.sample_freq; | |
10604 | ||
10605 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10606 | hwc->sample_period = event->attr.sample_period; | |
10607 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10608 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10609 | event->attr.freq = 0; |
10610 | } | |
10611 | } | |
10612 | ||
b0a873eb PZ |
10613 | /* |
10614 | * Software event: cpu wall time clock | |
10615 | */ | |
10616 | ||
10617 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10618 | { |
b0a873eb PZ |
10619 | s64 prev; |
10620 | u64 now; | |
10621 | ||
a4eaf7f1 | 10622 | now = local_clock(); |
b0a873eb PZ |
10623 | prev = local64_xchg(&event->hw.prev_count, now); |
10624 | local64_add(now - prev, &event->count); | |
24f1e32c | 10625 | } |
24f1e32c | 10626 | |
a4eaf7f1 | 10627 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10628 | { |
a4eaf7f1 | 10629 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10630 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10631 | } |
10632 | ||
a4eaf7f1 | 10633 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10634 | { |
b0a873eb PZ |
10635 | perf_swevent_cancel_hrtimer(event); |
10636 | cpu_clock_event_update(event); | |
10637 | } | |
f29ac756 | 10638 | |
a4eaf7f1 PZ |
10639 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10640 | { | |
10641 | if (flags & PERF_EF_START) | |
10642 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10643 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10644 | |
10645 | return 0; | |
10646 | } | |
10647 | ||
10648 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10649 | { | |
10650 | cpu_clock_event_stop(event, flags); | |
10651 | } | |
10652 | ||
b0a873eb PZ |
10653 | static void cpu_clock_event_read(struct perf_event *event) |
10654 | { | |
10655 | cpu_clock_event_update(event); | |
10656 | } | |
f344011c | 10657 | |
b0a873eb PZ |
10658 | static int cpu_clock_event_init(struct perf_event *event) |
10659 | { | |
10660 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10661 | return -ENOENT; | |
10662 | ||
10663 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10664 | return -ENOENT; | |
10665 | ||
2481c5fa SE |
10666 | /* |
10667 | * no branch sampling for software events | |
10668 | */ | |
10669 | if (has_branch_stack(event)) | |
10670 | return -EOPNOTSUPP; | |
10671 | ||
ba3dd36c PZ |
10672 | perf_swevent_init_hrtimer(event); |
10673 | ||
b0a873eb | 10674 | return 0; |
f29ac756 PZ |
10675 | } |
10676 | ||
b0a873eb | 10677 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10678 | .task_ctx_nr = perf_sw_context, |
10679 | ||
34f43927 PZ |
10680 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10681 | ||
b0a873eb | 10682 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10683 | .add = cpu_clock_event_add, |
10684 | .del = cpu_clock_event_del, | |
10685 | .start = cpu_clock_event_start, | |
10686 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10687 | .read = cpu_clock_event_read, |
10688 | }; | |
10689 | ||
10690 | /* | |
10691 | * Software event: task time clock | |
10692 | */ | |
10693 | ||
10694 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10695 | { |
b0a873eb PZ |
10696 | u64 prev; |
10697 | s64 delta; | |
5c92d124 | 10698 | |
b0a873eb PZ |
10699 | prev = local64_xchg(&event->hw.prev_count, now); |
10700 | delta = now - prev; | |
10701 | local64_add(delta, &event->count); | |
10702 | } | |
5c92d124 | 10703 | |
a4eaf7f1 | 10704 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10705 | { |
a4eaf7f1 | 10706 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10707 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10708 | } |
10709 | ||
a4eaf7f1 | 10710 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10711 | { |
10712 | perf_swevent_cancel_hrtimer(event); | |
10713 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10714 | } |
10715 | ||
10716 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10717 | { | |
10718 | if (flags & PERF_EF_START) | |
10719 | task_clock_event_start(event, flags); | |
6a694a60 | 10720 | perf_event_update_userpage(event); |
b0a873eb | 10721 | |
a4eaf7f1 PZ |
10722 | return 0; |
10723 | } | |
10724 | ||
10725 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10726 | { | |
10727 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10728 | } |
10729 | ||
10730 | static void task_clock_event_read(struct perf_event *event) | |
10731 | { | |
768a06e2 PZ |
10732 | u64 now = perf_clock(); |
10733 | u64 delta = now - event->ctx->timestamp; | |
10734 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10735 | |
10736 | task_clock_event_update(event, time); | |
10737 | } | |
10738 | ||
10739 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10740 | { |
b0a873eb PZ |
10741 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10742 | return -ENOENT; | |
10743 | ||
10744 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10745 | return -ENOENT; | |
10746 | ||
2481c5fa SE |
10747 | /* |
10748 | * no branch sampling for software events | |
10749 | */ | |
10750 | if (has_branch_stack(event)) | |
10751 | return -EOPNOTSUPP; | |
10752 | ||
ba3dd36c PZ |
10753 | perf_swevent_init_hrtimer(event); |
10754 | ||
b0a873eb | 10755 | return 0; |
6fb2915d LZ |
10756 | } |
10757 | ||
b0a873eb | 10758 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10759 | .task_ctx_nr = perf_sw_context, |
10760 | ||
34f43927 PZ |
10761 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10762 | ||
b0a873eb | 10763 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10764 | .add = task_clock_event_add, |
10765 | .del = task_clock_event_del, | |
10766 | .start = task_clock_event_start, | |
10767 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10768 | .read = task_clock_event_read, |
10769 | }; | |
6fb2915d | 10770 | |
ad5133b7 | 10771 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10772 | { |
e077df4f | 10773 | } |
6fb2915d | 10774 | |
fbbe0701 SB |
10775 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10776 | { | |
10777 | } | |
10778 | ||
ad5133b7 | 10779 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10780 | { |
ad5133b7 | 10781 | return 0; |
6fb2915d LZ |
10782 | } |
10783 | ||
81ec3f3c JO |
10784 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10785 | { | |
10786 | return 0; | |
10787 | } | |
10788 | ||
18ab2cd3 | 10789 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10790 | |
10791 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10792 | { |
fbbe0701 SB |
10793 | __this_cpu_write(nop_txn_flags, flags); |
10794 | ||
10795 | if (flags & ~PERF_PMU_TXN_ADD) | |
10796 | return; | |
10797 | ||
ad5133b7 | 10798 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10799 | } |
10800 | ||
ad5133b7 PZ |
10801 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10802 | { | |
fbbe0701 SB |
10803 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10804 | ||
10805 | __this_cpu_write(nop_txn_flags, 0); | |
10806 | ||
10807 | if (flags & ~PERF_PMU_TXN_ADD) | |
10808 | return 0; | |
10809 | ||
ad5133b7 PZ |
10810 | perf_pmu_enable(pmu); |
10811 | return 0; | |
10812 | } | |
e077df4f | 10813 | |
ad5133b7 | 10814 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10815 | { |
fbbe0701 SB |
10816 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10817 | ||
10818 | __this_cpu_write(nop_txn_flags, 0); | |
10819 | ||
10820 | if (flags & ~PERF_PMU_TXN_ADD) | |
10821 | return; | |
10822 | ||
ad5133b7 | 10823 | perf_pmu_enable(pmu); |
24f1e32c FW |
10824 | } |
10825 | ||
35edc2a5 PZ |
10826 | static int perf_event_idx_default(struct perf_event *event) |
10827 | { | |
c719f560 | 10828 | return 0; |
35edc2a5 PZ |
10829 | } |
10830 | ||
8dc85d54 PZ |
10831 | /* |
10832 | * Ensures all contexts with the same task_ctx_nr have the same | |
10833 | * pmu_cpu_context too. | |
10834 | */ | |
9e317041 | 10835 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10836 | { |
8dc85d54 | 10837 | struct pmu *pmu; |
b326e956 | 10838 | |
8dc85d54 PZ |
10839 | if (ctxn < 0) |
10840 | return NULL; | |
24f1e32c | 10841 | |
8dc85d54 PZ |
10842 | list_for_each_entry(pmu, &pmus, entry) { |
10843 | if (pmu->task_ctx_nr == ctxn) | |
10844 | return pmu->pmu_cpu_context; | |
10845 | } | |
24f1e32c | 10846 | |
8dc85d54 | 10847 | return NULL; |
24f1e32c FW |
10848 | } |
10849 | ||
51676957 PZ |
10850 | static void free_pmu_context(struct pmu *pmu) |
10851 | { | |
df0062b2 WD |
10852 | /* |
10853 | * Static contexts such as perf_sw_context have a global lifetime | |
10854 | * and may be shared between different PMUs. Avoid freeing them | |
10855 | * when a single PMU is going away. | |
10856 | */ | |
10857 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10858 | return; | |
10859 | ||
51676957 | 10860 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10861 | } |
6e855cd4 AS |
10862 | |
10863 | /* | |
10864 | * Let userspace know that this PMU supports address range filtering: | |
10865 | */ | |
10866 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10867 | struct device_attribute *attr, | |
10868 | char *page) | |
10869 | { | |
10870 | struct pmu *pmu = dev_get_drvdata(dev); | |
10871 | ||
10872 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10873 | } | |
10874 | DEVICE_ATTR_RO(nr_addr_filters); | |
10875 | ||
2e80a82a | 10876 | static struct idr pmu_idr; |
d6d020e9 | 10877 | |
abe43400 PZ |
10878 | static ssize_t |
10879 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10880 | { | |
10881 | struct pmu *pmu = dev_get_drvdata(dev); | |
10882 | ||
10883 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10884 | } | |
90826ca7 | 10885 | static DEVICE_ATTR_RO(type); |
abe43400 | 10886 | |
62b85639 SE |
10887 | static ssize_t |
10888 | perf_event_mux_interval_ms_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->hrtimer_interval_ms); | |
10895 | } | |
10896 | ||
272325c4 PZ |
10897 | static DEFINE_MUTEX(mux_interval_mutex); |
10898 | ||
62b85639 SE |
10899 | static ssize_t |
10900 | perf_event_mux_interval_ms_store(struct device *dev, | |
10901 | struct device_attribute *attr, | |
10902 | const char *buf, size_t count) | |
10903 | { | |
10904 | struct pmu *pmu = dev_get_drvdata(dev); | |
10905 | int timer, cpu, ret; | |
10906 | ||
10907 | ret = kstrtoint(buf, 0, &timer); | |
10908 | if (ret) | |
10909 | return ret; | |
10910 | ||
10911 | if (timer < 1) | |
10912 | return -EINVAL; | |
10913 | ||
10914 | /* same value, noting to do */ | |
10915 | if (timer == pmu->hrtimer_interval_ms) | |
10916 | return count; | |
10917 | ||
272325c4 | 10918 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10919 | pmu->hrtimer_interval_ms = timer; |
10920 | ||
10921 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10922 | cpus_read_lock(); |
272325c4 | 10923 | for_each_online_cpu(cpu) { |
62b85639 SE |
10924 | struct perf_cpu_context *cpuctx; |
10925 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10926 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10927 | ||
272325c4 PZ |
10928 | cpu_function_call(cpu, |
10929 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10930 | } |
a63fbed7 | 10931 | cpus_read_unlock(); |
272325c4 | 10932 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10933 | |
10934 | return count; | |
10935 | } | |
90826ca7 | 10936 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10937 | |
90826ca7 GKH |
10938 | static struct attribute *pmu_dev_attrs[] = { |
10939 | &dev_attr_type.attr, | |
10940 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10941 | NULL, | |
abe43400 | 10942 | }; |
90826ca7 | 10943 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10944 | |
10945 | static int pmu_bus_running; | |
10946 | static struct bus_type pmu_bus = { | |
10947 | .name = "event_source", | |
90826ca7 | 10948 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10949 | }; |
10950 | ||
10951 | static void pmu_dev_release(struct device *dev) | |
10952 | { | |
10953 | kfree(dev); | |
10954 | } | |
10955 | ||
10956 | static int pmu_dev_alloc(struct pmu *pmu) | |
10957 | { | |
10958 | int ret = -ENOMEM; | |
10959 | ||
10960 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10961 | if (!pmu->dev) | |
10962 | goto out; | |
10963 | ||
0c9d42ed | 10964 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10965 | device_initialize(pmu->dev); |
10966 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10967 | if (ret) | |
10968 | goto free_dev; | |
10969 | ||
10970 | dev_set_drvdata(pmu->dev, pmu); | |
10971 | pmu->dev->bus = &pmu_bus; | |
10972 | pmu->dev->release = pmu_dev_release; | |
10973 | ret = device_add(pmu->dev); | |
10974 | if (ret) | |
10975 | goto free_dev; | |
10976 | ||
6e855cd4 AS |
10977 | /* For PMUs with address filters, throw in an extra attribute: */ |
10978 | if (pmu->nr_addr_filters) | |
10979 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10980 | ||
10981 | if (ret) | |
10982 | goto del_dev; | |
10983 | ||
f3a3a825 JO |
10984 | if (pmu->attr_update) |
10985 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10986 | ||
10987 | if (ret) | |
10988 | goto del_dev; | |
10989 | ||
abe43400 PZ |
10990 | out: |
10991 | return ret; | |
10992 | ||
6e855cd4 AS |
10993 | del_dev: |
10994 | device_del(pmu->dev); | |
10995 | ||
abe43400 PZ |
10996 | free_dev: |
10997 | put_device(pmu->dev); | |
10998 | goto out; | |
10999 | } | |
11000 | ||
547e9fd7 | 11001 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 11002 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 11003 | |
03d8e80b | 11004 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 11005 | { |
66d258c5 | 11006 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 11007 | |
b0a873eb | 11008 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
11009 | ret = -ENOMEM; |
11010 | pmu->pmu_disable_count = alloc_percpu(int); | |
11011 | if (!pmu->pmu_disable_count) | |
11012 | goto unlock; | |
f29ac756 | 11013 | |
2e80a82a PZ |
11014 | pmu->type = -1; |
11015 | if (!name) | |
11016 | goto skip_type; | |
11017 | pmu->name = name; | |
11018 | ||
66d258c5 PZ |
11019 | if (type != PERF_TYPE_SOFTWARE) { |
11020 | if (type >= 0) | |
11021 | max = type; | |
11022 | ||
11023 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
11024 | if (ret < 0) | |
2e80a82a | 11025 | goto free_pdc; |
66d258c5 PZ |
11026 | |
11027 | WARN_ON(type >= 0 && ret != type); | |
11028 | ||
11029 | type = ret; | |
2e80a82a PZ |
11030 | } |
11031 | pmu->type = type; | |
11032 | ||
abe43400 PZ |
11033 | if (pmu_bus_running) { |
11034 | ret = pmu_dev_alloc(pmu); | |
11035 | if (ret) | |
11036 | goto free_idr; | |
11037 | } | |
11038 | ||
2e80a82a | 11039 | skip_type: |
26657848 PZ |
11040 | if (pmu->task_ctx_nr == perf_hw_context) { |
11041 | static int hw_context_taken = 0; | |
11042 | ||
5101ef20 MR |
11043 | /* |
11044 | * Other than systems with heterogeneous CPUs, it never makes | |
11045 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
11046 | * uncore must use perf_invalid_context. | |
11047 | */ | |
11048 | if (WARN_ON_ONCE(hw_context_taken && | |
11049 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
11050 | pmu->task_ctx_nr = perf_invalid_context; |
11051 | ||
11052 | hw_context_taken = 1; | |
11053 | } | |
11054 | ||
8dc85d54 PZ |
11055 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
11056 | if (pmu->pmu_cpu_context) | |
11057 | goto got_cpu_context; | |
f29ac756 | 11058 | |
c4814202 | 11059 | ret = -ENOMEM; |
108b02cf PZ |
11060 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
11061 | if (!pmu->pmu_cpu_context) | |
abe43400 | 11062 | goto free_dev; |
f344011c | 11063 | |
108b02cf PZ |
11064 | for_each_possible_cpu(cpu) { |
11065 | struct perf_cpu_context *cpuctx; | |
11066 | ||
11067 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 11068 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 11069 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 11070 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 11071 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 11072 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 11073 | |
272325c4 | 11074 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
11075 | |
11076 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
11077 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 11078 | } |
76e1d904 | 11079 | |
8dc85d54 | 11080 | got_cpu_context: |
ad5133b7 PZ |
11081 | if (!pmu->start_txn) { |
11082 | if (pmu->pmu_enable) { | |
11083 | /* | |
11084 | * If we have pmu_enable/pmu_disable calls, install | |
11085 | * transaction stubs that use that to try and batch | |
11086 | * hardware accesses. | |
11087 | */ | |
11088 | pmu->start_txn = perf_pmu_start_txn; | |
11089 | pmu->commit_txn = perf_pmu_commit_txn; | |
11090 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
11091 | } else { | |
fbbe0701 | 11092 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
11093 | pmu->commit_txn = perf_pmu_nop_int; |
11094 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 11095 | } |
5c92d124 | 11096 | } |
15dbf27c | 11097 | |
ad5133b7 PZ |
11098 | if (!pmu->pmu_enable) { |
11099 | pmu->pmu_enable = perf_pmu_nop_void; | |
11100 | pmu->pmu_disable = perf_pmu_nop_void; | |
11101 | } | |
11102 | ||
81ec3f3c JO |
11103 | if (!pmu->check_period) |
11104 | pmu->check_period = perf_event_nop_int; | |
11105 | ||
35edc2a5 PZ |
11106 | if (!pmu->event_idx) |
11107 | pmu->event_idx = perf_event_idx_default; | |
11108 | ||
d44f821b LK |
11109 | /* |
11110 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
11111 | * since these cannot be in the IDR. This way the linear search | |
11112 | * is fast, provided a valid software event is provided. | |
11113 | */ | |
11114 | if (type == PERF_TYPE_SOFTWARE || !name) | |
11115 | list_add_rcu(&pmu->entry, &pmus); | |
11116 | else | |
11117 | list_add_tail_rcu(&pmu->entry, &pmus); | |
11118 | ||
bed5b25a | 11119 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
11120 | ret = 0; |
11121 | unlock: | |
b0a873eb PZ |
11122 | mutex_unlock(&pmus_lock); |
11123 | ||
33696fc0 | 11124 | return ret; |
108b02cf | 11125 | |
abe43400 PZ |
11126 | free_dev: |
11127 | device_del(pmu->dev); | |
11128 | put_device(pmu->dev); | |
11129 | ||
2e80a82a | 11130 | free_idr: |
66d258c5 | 11131 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
11132 | idr_remove(&pmu_idr, pmu->type); |
11133 | ||
108b02cf PZ |
11134 | free_pdc: |
11135 | free_percpu(pmu->pmu_disable_count); | |
11136 | goto unlock; | |
f29ac756 | 11137 | } |
c464c76e | 11138 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 11139 | |
b0a873eb | 11140 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 11141 | { |
b0a873eb PZ |
11142 | mutex_lock(&pmus_lock); |
11143 | list_del_rcu(&pmu->entry); | |
5c92d124 | 11144 | |
0475f9ea | 11145 | /* |
cde8e884 PZ |
11146 | * We dereference the pmu list under both SRCU and regular RCU, so |
11147 | * synchronize against both of those. | |
0475f9ea | 11148 | */ |
b0a873eb | 11149 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 11150 | synchronize_rcu(); |
d6d020e9 | 11151 | |
33696fc0 | 11152 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 11153 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 11154 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 11155 | if (pmu_bus_running) { |
0933840a JO |
11156 | if (pmu->nr_addr_filters) |
11157 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
11158 | device_del(pmu->dev); | |
11159 | put_device(pmu->dev); | |
11160 | } | |
51676957 | 11161 | free_pmu_context(pmu); |
a9f97721 | 11162 | mutex_unlock(&pmus_lock); |
b0a873eb | 11163 | } |
c464c76e | 11164 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 11165 | |
e321d02d KL |
11166 | static inline bool has_extended_regs(struct perf_event *event) |
11167 | { | |
11168 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
11169 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
11170 | } | |
11171 | ||
cc34b98b MR |
11172 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
11173 | { | |
ccd41c86 | 11174 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
11175 | int ret; |
11176 | ||
11177 | if (!try_module_get(pmu->module)) | |
11178 | return -ENODEV; | |
ccd41c86 | 11179 | |
0c7296ca PZ |
11180 | /* |
11181 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
11182 | * for example, validate if the group fits on the PMU. Therefore, | |
11183 | * if this is a sibling event, acquire the ctx->mutex to protect | |
11184 | * the sibling_list. | |
11185 | */ | |
11186 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
11187 | /* |
11188 | * This ctx->mutex can nest when we're called through | |
11189 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
11190 | */ | |
11191 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
11192 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
11193 | BUG_ON(!ctx); |
11194 | } | |
11195 | ||
cc34b98b MR |
11196 | event->pmu = pmu; |
11197 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
11198 | |
11199 | if (ctx) | |
11200 | perf_event_ctx_unlock(event->group_leader, ctx); | |
11201 | ||
cc6795ae | 11202 | if (!ret) { |
e321d02d KL |
11203 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
11204 | has_extended_regs(event)) | |
11205 | ret = -EOPNOTSUPP; | |
11206 | ||
cc6795ae | 11207 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 11208 | event_has_any_exclude_flag(event)) |
cc6795ae | 11209 | ret = -EINVAL; |
e321d02d KL |
11210 | |
11211 | if (ret && event->destroy) | |
11212 | event->destroy(event); | |
cc6795ae AM |
11213 | } |
11214 | ||
cc34b98b MR |
11215 | if (ret) |
11216 | module_put(pmu->module); | |
11217 | ||
11218 | return ret; | |
11219 | } | |
11220 | ||
18ab2cd3 | 11221 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 11222 | { |
66d258c5 | 11223 | int idx, type, ret; |
85c617ab | 11224 | struct pmu *pmu; |
b0a873eb PZ |
11225 | |
11226 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 11227 | |
40999312 KL |
11228 | /* Try parent's PMU first: */ |
11229 | if (event->parent && event->parent->pmu) { | |
11230 | pmu = event->parent->pmu; | |
11231 | ret = perf_try_init_event(pmu, event); | |
11232 | if (!ret) | |
11233 | goto unlock; | |
11234 | } | |
11235 | ||
66d258c5 PZ |
11236 | /* |
11237 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
11238 | * are often aliases for PERF_TYPE_RAW. | |
11239 | */ | |
11240 | type = event->attr.type; | |
11241 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
11242 | type = PERF_TYPE_RAW; | |
11243 | ||
11244 | again: | |
2e80a82a | 11245 | rcu_read_lock(); |
66d258c5 | 11246 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 11247 | rcu_read_unlock(); |
940c5b29 | 11248 | if (pmu) { |
cc34b98b | 11249 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
11250 | if (ret == -ENOENT && event->attr.type != type) { |
11251 | type = event->attr.type; | |
11252 | goto again; | |
11253 | } | |
11254 | ||
940c5b29 LM |
11255 | if (ret) |
11256 | pmu = ERR_PTR(ret); | |
66d258c5 | 11257 | |
2e80a82a | 11258 | goto unlock; |
940c5b29 | 11259 | } |
2e80a82a | 11260 | |
9f0bff11 | 11261 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 11262 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 11263 | if (!ret) |
e5f4d339 | 11264 | goto unlock; |
76e1d904 | 11265 | |
b0a873eb PZ |
11266 | if (ret != -ENOENT) { |
11267 | pmu = ERR_PTR(ret); | |
e5f4d339 | 11268 | goto unlock; |
f344011c | 11269 | } |
5c92d124 | 11270 | } |
e5f4d339 PZ |
11271 | pmu = ERR_PTR(-ENOENT); |
11272 | unlock: | |
b0a873eb | 11273 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 11274 | |
4aeb0b42 | 11275 | return pmu; |
5c92d124 IM |
11276 | } |
11277 | ||
f2fb6bef KL |
11278 | static void attach_sb_event(struct perf_event *event) |
11279 | { | |
11280 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
11281 | ||
11282 | raw_spin_lock(&pel->lock); | |
11283 | list_add_rcu(&event->sb_list, &pel->list); | |
11284 | raw_spin_unlock(&pel->lock); | |
11285 | } | |
11286 | ||
aab5b71e PZ |
11287 | /* |
11288 | * We keep a list of all !task (and therefore per-cpu) events | |
11289 | * that need to receive side-band records. | |
11290 | * | |
11291 | * This avoids having to scan all the various PMU per-cpu contexts | |
11292 | * looking for them. | |
11293 | */ | |
f2fb6bef KL |
11294 | static void account_pmu_sb_event(struct perf_event *event) |
11295 | { | |
a4f144eb | 11296 | if (is_sb_event(event)) |
f2fb6bef KL |
11297 | attach_sb_event(event); |
11298 | } | |
11299 | ||
4beb31f3 FW |
11300 | static void account_event_cpu(struct perf_event *event, int cpu) |
11301 | { | |
11302 | if (event->parent) | |
11303 | return; | |
11304 | ||
4beb31f3 FW |
11305 | if (is_cgroup_event(event)) |
11306 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
11307 | } | |
11308 | ||
555e0c1e FW |
11309 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
11310 | static void account_freq_event_nohz(void) | |
11311 | { | |
11312 | #ifdef CONFIG_NO_HZ_FULL | |
11313 | /* Lock so we don't race with concurrent unaccount */ | |
11314 | spin_lock(&nr_freq_lock); | |
11315 | if (atomic_inc_return(&nr_freq_events) == 1) | |
11316 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
11317 | spin_unlock(&nr_freq_lock); | |
11318 | #endif | |
11319 | } | |
11320 | ||
11321 | static void account_freq_event(void) | |
11322 | { | |
11323 | if (tick_nohz_full_enabled()) | |
11324 | account_freq_event_nohz(); | |
11325 | else | |
11326 | atomic_inc(&nr_freq_events); | |
11327 | } | |
11328 | ||
11329 | ||
766d6c07 FW |
11330 | static void account_event(struct perf_event *event) |
11331 | { | |
25432ae9 PZ |
11332 | bool inc = false; |
11333 | ||
4beb31f3 FW |
11334 | if (event->parent) |
11335 | return; | |
11336 | ||
a5398bff | 11337 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 11338 | inc = true; |
766d6c07 FW |
11339 | if (event->attr.mmap || event->attr.mmap_data) |
11340 | atomic_inc(&nr_mmap_events); | |
88a16a13 JO |
11341 | if (event->attr.build_id) |
11342 | atomic_inc(&nr_build_id_events); | |
766d6c07 FW |
11343 | if (event->attr.comm) |
11344 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
11345 | if (event->attr.namespaces) |
11346 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
11347 | if (event->attr.cgroup) |
11348 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
11349 | if (event->attr.task) |
11350 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
11351 | if (event->attr.freq) |
11352 | account_freq_event(); | |
45ac1403 AH |
11353 | if (event->attr.context_switch) { |
11354 | atomic_inc(&nr_switch_events); | |
25432ae9 | 11355 | inc = true; |
45ac1403 | 11356 | } |
4beb31f3 | 11357 | if (has_branch_stack(event)) |
25432ae9 | 11358 | inc = true; |
4beb31f3 | 11359 | if (is_cgroup_event(event)) |
25432ae9 | 11360 | inc = true; |
76193a94 SL |
11361 | if (event->attr.ksymbol) |
11362 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
11363 | if (event->attr.bpf_event) |
11364 | atomic_inc(&nr_bpf_events); | |
e17d43b9 AH |
11365 | if (event->attr.text_poke) |
11366 | atomic_inc(&nr_text_poke_events); | |
25432ae9 | 11367 | |
9107c89e | 11368 | if (inc) { |
5bce9db1 AS |
11369 | /* |
11370 | * We need the mutex here because static_branch_enable() | |
11371 | * must complete *before* the perf_sched_count increment | |
11372 | * becomes visible. | |
11373 | */ | |
9107c89e PZ |
11374 | if (atomic_inc_not_zero(&perf_sched_count)) |
11375 | goto enabled; | |
11376 | ||
11377 | mutex_lock(&perf_sched_mutex); | |
11378 | if (!atomic_read(&perf_sched_count)) { | |
11379 | static_branch_enable(&perf_sched_events); | |
11380 | /* | |
11381 | * Guarantee that all CPUs observe they key change and | |
11382 | * call the perf scheduling hooks before proceeding to | |
11383 | * install events that need them. | |
11384 | */ | |
0809d954 | 11385 | synchronize_rcu(); |
9107c89e PZ |
11386 | } |
11387 | /* | |
11388 | * Now that we have waited for the sync_sched(), allow further | |
11389 | * increments to by-pass the mutex. | |
11390 | */ | |
11391 | atomic_inc(&perf_sched_count); | |
11392 | mutex_unlock(&perf_sched_mutex); | |
11393 | } | |
11394 | enabled: | |
4beb31f3 FW |
11395 | |
11396 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
11397 | |
11398 | account_pmu_sb_event(event); | |
766d6c07 FW |
11399 | } |
11400 | ||
0793a61d | 11401 | /* |
788faab7 | 11402 | * Allocate and initialize an event structure |
0793a61d | 11403 | */ |
cdd6c482 | 11404 | static struct perf_event * |
c3f00c70 | 11405 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
11406 | struct task_struct *task, |
11407 | struct perf_event *group_leader, | |
11408 | struct perf_event *parent_event, | |
4dc0da86 | 11409 | perf_overflow_handler_t overflow_handler, |
79dff51e | 11410 | void *context, int cgroup_fd) |
0793a61d | 11411 | { |
51b0fe39 | 11412 | struct pmu *pmu; |
cdd6c482 IM |
11413 | struct perf_event *event; |
11414 | struct hw_perf_event *hwc; | |
90983b16 | 11415 | long err = -EINVAL; |
ff65338e | 11416 | int node; |
0793a61d | 11417 | |
66832eb4 ON |
11418 | if ((unsigned)cpu >= nr_cpu_ids) { |
11419 | if (!task || cpu != -1) | |
11420 | return ERR_PTR(-EINVAL); | |
11421 | } | |
97ba62b2 ME |
11422 | if (attr->sigtrap && !task) { |
11423 | /* Requires a task: avoid signalling random tasks. */ | |
11424 | return ERR_PTR(-EINVAL); | |
11425 | } | |
66832eb4 | 11426 | |
ff65338e NK |
11427 | node = (cpu >= 0) ? cpu_to_node(cpu) : -1; |
11428 | event = kmem_cache_alloc_node(perf_event_cache, GFP_KERNEL | __GFP_ZERO, | |
11429 | node); | |
cdd6c482 | 11430 | if (!event) |
d5d2bc0d | 11431 | return ERR_PTR(-ENOMEM); |
0793a61d | 11432 | |
04289bb9 | 11433 | /* |
cdd6c482 | 11434 | * Single events are their own group leaders, with an |
04289bb9 IM |
11435 | * empty sibling list: |
11436 | */ | |
11437 | if (!group_leader) | |
cdd6c482 | 11438 | group_leader = event; |
04289bb9 | 11439 | |
cdd6c482 IM |
11440 | mutex_init(&event->child_mutex); |
11441 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 11442 | |
cdd6c482 IM |
11443 | INIT_LIST_HEAD(&event->event_entry); |
11444 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 11445 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 11446 | init_event_group(event); |
10c6db11 | 11447 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 11448 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 11449 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
11450 | INIT_HLIST_NODE(&event->hlist_entry); |
11451 | ||
10c6db11 | 11452 | |
cdd6c482 | 11453 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 11454 | event->pending_disable = -1; |
e360adbe | 11455 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 11456 | |
cdd6c482 | 11457 | mutex_init(&event->mmap_mutex); |
375637bc | 11458 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11459 | |
a6fa941d | 11460 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11461 | event->cpu = cpu; |
11462 | event->attr = *attr; | |
11463 | event->group_leader = group_leader; | |
11464 | event->pmu = NULL; | |
cdd6c482 | 11465 | event->oncpu = -1; |
a96bbc16 | 11466 | |
cdd6c482 | 11467 | event->parent = parent_event; |
b84fbc9f | 11468 | |
17cf22c3 | 11469 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11470 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11471 | |
cdd6c482 | 11472 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11473 | |
97ba62b2 ME |
11474 | if (event->attr.sigtrap) |
11475 | atomic_set(&event->event_limit, 1); | |
11476 | ||
d580ff86 PZ |
11477 | if (task) { |
11478 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11479 | /* |
50f16a8b PZ |
11480 | * XXX pmu::event_init needs to know what task to account to |
11481 | * and we cannot use the ctx information because we need the | |
11482 | * pmu before we get a ctx. | |
d580ff86 | 11483 | */ |
7b3c92b8 | 11484 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11485 | } |
11486 | ||
34f43927 PZ |
11487 | event->clock = &local_clock; |
11488 | if (parent_event) | |
11489 | event->clock = parent_event->clock; | |
11490 | ||
4dc0da86 | 11491 | if (!overflow_handler && parent_event) { |
b326e956 | 11492 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11493 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11494 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11495 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11496 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11497 | |
85192dbf | 11498 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11499 | event->prog = prog; |
11500 | event->orig_overflow_handler = | |
11501 | parent_event->orig_overflow_handler; | |
11502 | } | |
11503 | #endif | |
4dc0da86 | 11504 | } |
66832eb4 | 11505 | |
1879445d WN |
11506 | if (overflow_handler) { |
11507 | event->overflow_handler = overflow_handler; | |
11508 | event->overflow_handler_context = context; | |
9ecda41a WN |
11509 | } else if (is_write_backward(event)){ |
11510 | event->overflow_handler = perf_event_output_backward; | |
11511 | event->overflow_handler_context = NULL; | |
1879445d | 11512 | } else { |
9ecda41a | 11513 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11514 | event->overflow_handler_context = NULL; |
11515 | } | |
97eaf530 | 11516 | |
0231bb53 | 11517 | perf_event__state_init(event); |
a86ed508 | 11518 | |
4aeb0b42 | 11519 | pmu = NULL; |
b8e83514 | 11520 | |
cdd6c482 | 11521 | hwc = &event->hw; |
bd2b5b12 | 11522 | hwc->sample_period = attr->sample_period; |
0d48696f | 11523 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11524 | hwc->sample_period = 1; |
eced1dfc | 11525 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11526 | |
e7850595 | 11527 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11528 | |
2023b359 | 11529 | /* |
ba5213ae PZ |
11530 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11531 | * See perf_output_read(). | |
2023b359 | 11532 | */ |
ba5213ae | 11533 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11534 | goto err_ns; |
a46a2300 YZ |
11535 | |
11536 | if (!has_branch_stack(event)) | |
11537 | event->attr.branch_sample_type = 0; | |
2023b359 | 11538 | |
b0a873eb | 11539 | pmu = perf_init_event(event); |
85c617ab | 11540 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11541 | err = PTR_ERR(pmu); |
90983b16 | 11542 | goto err_ns; |
621a01ea | 11543 | } |
d5d2bc0d | 11544 | |
09f4e8f0 PZ |
11545 | /* |
11546 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11547 | * be different on other CPUs in the uncore mask. | |
11548 | */ | |
11549 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11550 | err = -EINVAL; | |
11551 | goto err_pmu; | |
11552 | } | |
11553 | ||
ab43762e AS |
11554 | if (event->attr.aux_output && |
11555 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11556 | err = -EOPNOTSUPP; | |
11557 | goto err_pmu; | |
11558 | } | |
11559 | ||
98add2af PZ |
11560 | if (cgroup_fd != -1) { |
11561 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11562 | if (err) | |
11563 | goto err_pmu; | |
11564 | } | |
11565 | ||
bed5b25a AS |
11566 | err = exclusive_event_init(event); |
11567 | if (err) | |
11568 | goto err_pmu; | |
11569 | ||
375637bc | 11570 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11571 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11572 | sizeof(struct perf_addr_filter_range), | |
11573 | GFP_KERNEL); | |
11574 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11575 | err = -ENOMEM; |
375637bc | 11576 | goto err_per_task; |
36cc2b92 | 11577 | } |
375637bc | 11578 | |
18736eef AS |
11579 | /* |
11580 | * Clone the parent's vma offsets: they are valid until exec() | |
11581 | * even if the mm is not shared with the parent. | |
11582 | */ | |
11583 | if (event->parent) { | |
11584 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11585 | ||
11586 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11587 | memcpy(event->addr_filter_ranges, |
11588 | event->parent->addr_filter_ranges, | |
11589 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11590 | raw_spin_unlock_irq(&ifh->lock); |
11591 | } | |
11592 | ||
375637bc AS |
11593 | /* force hw sync on the address filters */ |
11594 | event->addr_filters_gen = 1; | |
11595 | } | |
11596 | ||
cdd6c482 | 11597 | if (!event->parent) { |
927c7a9e | 11598 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11599 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11600 | if (err) |
375637bc | 11601 | goto err_addr_filters; |
d010b332 | 11602 | } |
f344011c | 11603 | } |
9ee318a7 | 11604 | |
da97e184 JFG |
11605 | err = security_perf_event_alloc(event); |
11606 | if (err) | |
11607 | goto err_callchain_buffer; | |
11608 | ||
927a5570 AS |
11609 | /* symmetric to unaccount_event() in _free_event() */ |
11610 | account_event(event); | |
11611 | ||
cdd6c482 | 11612 | return event; |
90983b16 | 11613 | |
da97e184 JFG |
11614 | err_callchain_buffer: |
11615 | if (!event->parent) { | |
11616 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11617 | put_callchain_buffers(); | |
11618 | } | |
375637bc | 11619 | err_addr_filters: |
c60f83b8 | 11620 | kfree(event->addr_filter_ranges); |
375637bc | 11621 | |
bed5b25a AS |
11622 | err_per_task: |
11623 | exclusive_event_destroy(event); | |
11624 | ||
90983b16 | 11625 | err_pmu: |
98add2af PZ |
11626 | if (is_cgroup_event(event)) |
11627 | perf_detach_cgroup(event); | |
90983b16 FW |
11628 | if (event->destroy) |
11629 | event->destroy(event); | |
c464c76e | 11630 | module_put(pmu->module); |
90983b16 FW |
11631 | err_ns: |
11632 | if (event->ns) | |
11633 | put_pid_ns(event->ns); | |
621b6d2e PB |
11634 | if (event->hw.target) |
11635 | put_task_struct(event->hw.target); | |
bdacfaf2 | 11636 | kmem_cache_free(perf_event_cache, event); |
90983b16 FW |
11637 | |
11638 | return ERR_PTR(err); | |
0793a61d TG |
11639 | } |
11640 | ||
cdd6c482 IM |
11641 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11642 | struct perf_event_attr *attr) | |
974802ea | 11643 | { |
974802ea | 11644 | u32 size; |
cdf8073d | 11645 | int ret; |
974802ea | 11646 | |
c2ba8f41 | 11647 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11648 | memset(attr, 0, sizeof(*attr)); |
11649 | ||
11650 | ret = get_user(size, &uattr->size); | |
11651 | if (ret) | |
11652 | return ret; | |
11653 | ||
c2ba8f41 AS |
11654 | /* ABI compatibility quirk: */ |
11655 | if (!size) | |
974802ea | 11656 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11657 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11658 | goto err_size; |
11659 | ||
c2ba8f41 AS |
11660 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11661 | if (ret) { | |
11662 | if (ret == -E2BIG) | |
11663 | goto err_size; | |
11664 | return ret; | |
974802ea PZ |
11665 | } |
11666 | ||
f12f42ac MX |
11667 | attr->size = size; |
11668 | ||
a4faf00d | 11669 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11670 | return -EINVAL; |
11671 | ||
11672 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11673 | return -EINVAL; | |
11674 | ||
11675 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11676 | return -EINVAL; | |
11677 | ||
bce38cd5 SE |
11678 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11679 | u64 mask = attr->branch_sample_type; | |
11680 | ||
11681 | /* only using defined bits */ | |
11682 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11683 | return -EINVAL; | |
11684 | ||
11685 | /* at least one branch bit must be set */ | |
11686 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11687 | return -EINVAL; | |
11688 | ||
bce38cd5 SE |
11689 | /* propagate priv level, when not set for branch */ |
11690 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11691 | ||
11692 | /* exclude_kernel checked on syscall entry */ | |
11693 | if (!attr->exclude_kernel) | |
11694 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11695 | ||
11696 | if (!attr->exclude_user) | |
11697 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11698 | ||
11699 | if (!attr->exclude_hv) | |
11700 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11701 | /* | |
11702 | * adjust user setting (for HW filter setup) | |
11703 | */ | |
11704 | attr->branch_sample_type = mask; | |
11705 | } | |
e712209a | 11706 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11707 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11708 | ret = perf_allow_kernel(attr); | |
11709 | if (ret) | |
11710 | return ret; | |
11711 | } | |
bce38cd5 | 11712 | } |
4018994f | 11713 | |
c5ebcedb | 11714 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11715 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11716 | if (ret) |
11717 | return ret; | |
11718 | } | |
11719 | ||
11720 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11721 | if (!arch_perf_have_user_stack_dump()) | |
11722 | return -ENOSYS; | |
11723 | ||
11724 | /* | |
11725 | * We have __u32 type for the size, but so far | |
11726 | * we can only use __u16 as maximum due to the | |
11727 | * __u16 sample size limit. | |
11728 | */ | |
11729 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11730 | return -EINVAL; |
c5ebcedb | 11731 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11732 | return -EINVAL; |
c5ebcedb | 11733 | } |
4018994f | 11734 | |
5f970521 JO |
11735 | if (!attr->sample_max_stack) |
11736 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11737 | ||
60e2364e SE |
11738 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11739 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11740 | |
11741 | #ifndef CONFIG_CGROUP_PERF | |
11742 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11743 | return -EINVAL; | |
11744 | #endif | |
2a6c6b7d KL |
11745 | if ((attr->sample_type & PERF_SAMPLE_WEIGHT) && |
11746 | (attr->sample_type & PERF_SAMPLE_WEIGHT_STRUCT)) | |
11747 | return -EINVAL; | |
6546b19f | 11748 | |
2b26f0aa ME |
11749 | if (!attr->inherit && attr->inherit_thread) |
11750 | return -EINVAL; | |
11751 | ||
2e498d0a ME |
11752 | if (attr->remove_on_exec && attr->enable_on_exec) |
11753 | return -EINVAL; | |
11754 | ||
97ba62b2 ME |
11755 | if (attr->sigtrap && !attr->remove_on_exec) |
11756 | return -EINVAL; | |
11757 | ||
974802ea PZ |
11758 | out: |
11759 | return ret; | |
11760 | ||
11761 | err_size: | |
11762 | put_user(sizeof(*attr), &uattr->size); | |
11763 | ret = -E2BIG; | |
11764 | goto out; | |
11765 | } | |
11766 | ||
ac9721f3 PZ |
11767 | static int |
11768 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11769 | { |
56de4e8f | 11770 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11771 | int ret = -EINVAL; |
11772 | ||
ac9721f3 | 11773 | if (!output_event) |
a4be7c27 PZ |
11774 | goto set; |
11775 | ||
ac9721f3 PZ |
11776 | /* don't allow circular references */ |
11777 | if (event == output_event) | |
a4be7c27 PZ |
11778 | goto out; |
11779 | ||
0f139300 PZ |
11780 | /* |
11781 | * Don't allow cross-cpu buffers | |
11782 | */ | |
11783 | if (output_event->cpu != event->cpu) | |
11784 | goto out; | |
11785 | ||
11786 | /* | |
76369139 | 11787 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11788 | */ |
11789 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11790 | goto out; | |
11791 | ||
34f43927 PZ |
11792 | /* |
11793 | * Mixing clocks in the same buffer is trouble you don't need. | |
11794 | */ | |
11795 | if (output_event->clock != event->clock) | |
11796 | goto out; | |
11797 | ||
9ecda41a WN |
11798 | /* |
11799 | * Either writing ring buffer from beginning or from end. | |
11800 | * Mixing is not allowed. | |
11801 | */ | |
11802 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11803 | goto out; | |
11804 | ||
45bfb2e5 PZ |
11805 | /* |
11806 | * If both events generate aux data, they must be on the same PMU | |
11807 | */ | |
11808 | if (has_aux(event) && has_aux(output_event) && | |
11809 | event->pmu != output_event->pmu) | |
11810 | goto out; | |
11811 | ||
a4be7c27 | 11812 | set: |
cdd6c482 | 11813 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11814 | /* Can't redirect output if we've got an active mmap() */ |
11815 | if (atomic_read(&event->mmap_count)) | |
11816 | goto unlock; | |
a4be7c27 | 11817 | |
ac9721f3 | 11818 | if (output_event) { |
76369139 FW |
11819 | /* get the rb we want to redirect to */ |
11820 | rb = ring_buffer_get(output_event); | |
11821 | if (!rb) | |
ac9721f3 | 11822 | goto unlock; |
a4be7c27 PZ |
11823 | } |
11824 | ||
b69cf536 | 11825 | ring_buffer_attach(event, rb); |
9bb5d40c | 11826 | |
a4be7c27 | 11827 | ret = 0; |
ac9721f3 PZ |
11828 | unlock: |
11829 | mutex_unlock(&event->mmap_mutex); | |
11830 | ||
a4be7c27 | 11831 | out: |
a4be7c27 PZ |
11832 | return ret; |
11833 | } | |
11834 | ||
f63a8daa PZ |
11835 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11836 | { | |
11837 | if (b < a) | |
11838 | swap(a, b); | |
11839 | ||
11840 | mutex_lock(a); | |
11841 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11842 | } | |
11843 | ||
34f43927 PZ |
11844 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11845 | { | |
11846 | bool nmi_safe = false; | |
11847 | ||
11848 | switch (clk_id) { | |
11849 | case CLOCK_MONOTONIC: | |
11850 | event->clock = &ktime_get_mono_fast_ns; | |
11851 | nmi_safe = true; | |
11852 | break; | |
11853 | ||
11854 | case CLOCK_MONOTONIC_RAW: | |
11855 | event->clock = &ktime_get_raw_fast_ns; | |
11856 | nmi_safe = true; | |
11857 | break; | |
11858 | ||
11859 | case CLOCK_REALTIME: | |
11860 | event->clock = &ktime_get_real_ns; | |
11861 | break; | |
11862 | ||
11863 | case CLOCK_BOOTTIME: | |
9285ec4c | 11864 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11865 | break; |
11866 | ||
11867 | case CLOCK_TAI: | |
9285ec4c | 11868 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11869 | break; |
11870 | ||
11871 | default: | |
11872 | return -EINVAL; | |
11873 | } | |
11874 | ||
11875 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11876 | return -EINVAL; | |
11877 | ||
11878 | return 0; | |
11879 | } | |
11880 | ||
321027c1 PZ |
11881 | /* |
11882 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11883 | * mutexes. | |
11884 | */ | |
11885 | static struct perf_event_context * | |
11886 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11887 | struct perf_event_context *ctx) | |
11888 | { | |
11889 | struct perf_event_context *gctx; | |
11890 | ||
11891 | again: | |
11892 | rcu_read_lock(); | |
11893 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11894 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11895 | rcu_read_unlock(); |
11896 | goto again; | |
11897 | } | |
11898 | rcu_read_unlock(); | |
11899 | ||
11900 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11901 | ||
11902 | if (group_leader->ctx != gctx) { | |
11903 | mutex_unlock(&ctx->mutex); | |
11904 | mutex_unlock(&gctx->mutex); | |
11905 | put_ctx(gctx); | |
11906 | goto again; | |
11907 | } | |
11908 | ||
11909 | return gctx; | |
11910 | } | |
11911 | ||
0793a61d | 11912 | /** |
cdd6c482 | 11913 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11914 | * |
cdd6c482 | 11915 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11916 | * @pid: target pid |
9f66a381 | 11917 | * @cpu: target cpu |
cdd6c482 | 11918 | * @group_fd: group leader event fd |
0793a61d | 11919 | */ |
cdd6c482 IM |
11920 | SYSCALL_DEFINE5(perf_event_open, |
11921 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11922 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11923 | { |
b04243ef PZ |
11924 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11925 | struct perf_event *event, *sibling; | |
cdd6c482 | 11926 | struct perf_event_attr attr; |
3f649ab7 | 11927 | struct perf_event_context *ctx, *gctx; |
cdd6c482 | 11928 | struct file *event_file = NULL; |
2903ff01 | 11929 | struct fd group = {NULL, 0}; |
38a81da2 | 11930 | struct task_struct *task = NULL; |
89a1e187 | 11931 | struct pmu *pmu; |
ea635c64 | 11932 | int event_fd; |
b04243ef | 11933 | int move_group = 0; |
dc86cabe | 11934 | int err; |
a21b0b35 | 11935 | int f_flags = O_RDWR; |
79dff51e | 11936 | int cgroup_fd = -1; |
0793a61d | 11937 | |
2743a5b0 | 11938 | /* for future expandability... */ |
e5d1367f | 11939 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11940 | return -EINVAL; |
11941 | ||
da97e184 JFG |
11942 | /* Do we allow access to perf_event_open(2) ? */ |
11943 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11944 | if (err) | |
11945 | return err; | |
11946 | ||
dc86cabe IM |
11947 | err = perf_copy_attr(attr_uptr, &attr); |
11948 | if (err) | |
11949 | return err; | |
eab656ae | 11950 | |
0764771d | 11951 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11952 | err = perf_allow_kernel(&attr); |
11953 | if (err) | |
11954 | return err; | |
0764771d PZ |
11955 | } |
11956 | ||
e4222673 | 11957 | if (attr.namespaces) { |
18aa1856 | 11958 | if (!perfmon_capable()) |
e4222673 HB |
11959 | return -EACCES; |
11960 | } | |
11961 | ||
df58ab24 | 11962 | if (attr.freq) { |
cdd6c482 | 11963 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11964 | return -EINVAL; |
0819b2e3 PZ |
11965 | } else { |
11966 | if (attr.sample_period & (1ULL << 63)) | |
11967 | return -EINVAL; | |
df58ab24 PZ |
11968 | } |
11969 | ||
fc7ce9c7 | 11970 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11971 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11972 | err = perf_allow_kernel(&attr); | |
11973 | if (err) | |
11974 | return err; | |
11975 | } | |
fc7ce9c7 | 11976 | |
08ef1af4 OM |
11977 | /* REGS_INTR can leak data, lockdown must prevent this */ |
11978 | if (attr.sample_type & PERF_SAMPLE_REGS_INTR) { | |
11979 | err = security_locked_down(LOCKDOWN_PERF); | |
11980 | if (err) | |
11981 | return err; | |
11982 | } | |
b0c8fdc7 | 11983 | |
e5d1367f SE |
11984 | /* |
11985 | * In cgroup mode, the pid argument is used to pass the fd | |
11986 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11987 | * designates the cpu on which to monitor threads from that | |
11988 | * cgroup. | |
11989 | */ | |
11990 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11991 | return -EINVAL; | |
11992 | ||
a21b0b35 YD |
11993 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11994 | f_flags |= O_CLOEXEC; | |
11995 | ||
11996 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11997 | if (event_fd < 0) |
11998 | return event_fd; | |
11999 | ||
ac9721f3 | 12000 | if (group_fd != -1) { |
2903ff01 AV |
12001 | err = perf_fget_light(group_fd, &group); |
12002 | if (err) | |
d14b12d7 | 12003 | goto err_fd; |
2903ff01 | 12004 | group_leader = group.file->private_data; |
ac9721f3 PZ |
12005 | if (flags & PERF_FLAG_FD_OUTPUT) |
12006 | output_event = group_leader; | |
12007 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
12008 | group_leader = NULL; | |
12009 | } | |
12010 | ||
e5d1367f | 12011 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
12012 | task = find_lively_task_by_vpid(pid); |
12013 | if (IS_ERR(task)) { | |
12014 | err = PTR_ERR(task); | |
12015 | goto err_group_fd; | |
12016 | } | |
12017 | } | |
12018 | ||
1f4ee503 PZ |
12019 | if (task && group_leader && |
12020 | group_leader->attr.inherit != attr.inherit) { | |
12021 | err = -EINVAL; | |
12022 | goto err_task; | |
12023 | } | |
12024 | ||
79dff51e MF |
12025 | if (flags & PERF_FLAG_PID_CGROUP) |
12026 | cgroup_fd = pid; | |
12027 | ||
4dc0da86 | 12028 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 12029 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
12030 | if (IS_ERR(event)) { |
12031 | err = PTR_ERR(event); | |
78af4dc9 | 12032 | goto err_task; |
d14b12d7 SE |
12033 | } |
12034 | ||
53b25335 VW |
12035 | if (is_sampling_event(event)) { |
12036 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 12037 | err = -EOPNOTSUPP; |
53b25335 VW |
12038 | goto err_alloc; |
12039 | } | |
12040 | } | |
12041 | ||
89a1e187 PZ |
12042 | /* |
12043 | * Special case software events and allow them to be part of | |
12044 | * any hardware group. | |
12045 | */ | |
12046 | pmu = event->pmu; | |
b04243ef | 12047 | |
34f43927 PZ |
12048 | if (attr.use_clockid) { |
12049 | err = perf_event_set_clock(event, attr.clockid); | |
12050 | if (err) | |
12051 | goto err_alloc; | |
12052 | } | |
12053 | ||
4ff6a8de DCC |
12054 | if (pmu->task_ctx_nr == perf_sw_context) |
12055 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
12056 | ||
a1150c20 SL |
12057 | if (group_leader) { |
12058 | if (is_software_event(event) && | |
12059 | !in_software_context(group_leader)) { | |
b04243ef | 12060 | /* |
a1150c20 SL |
12061 | * If the event is a sw event, but the group_leader |
12062 | * is on hw context. | |
b04243ef | 12063 | * |
a1150c20 SL |
12064 | * Allow the addition of software events to hw |
12065 | * groups, this is safe because software events | |
12066 | * never fail to schedule. | |
b04243ef | 12067 | */ |
a1150c20 SL |
12068 | pmu = group_leader->ctx->pmu; |
12069 | } else if (!is_software_event(event) && | |
12070 | is_software_event(group_leader) && | |
4ff6a8de | 12071 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
12072 | /* |
12073 | * In case the group is a pure software group, and we | |
12074 | * try to add a hardware event, move the whole group to | |
12075 | * the hardware context. | |
12076 | */ | |
12077 | move_group = 1; | |
12078 | } | |
12079 | } | |
89a1e187 PZ |
12080 | |
12081 | /* | |
12082 | * Get the target context (task or percpu): | |
12083 | */ | |
4af57ef2 | 12084 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
12085 | if (IS_ERR(ctx)) { |
12086 | err = PTR_ERR(ctx); | |
c6be5a5c | 12087 | goto err_alloc; |
89a1e187 PZ |
12088 | } |
12089 | ||
ccff286d | 12090 | /* |
cdd6c482 | 12091 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 12092 | */ |
ac9721f3 | 12093 | if (group_leader) { |
dc86cabe | 12094 | err = -EINVAL; |
04289bb9 | 12095 | |
04289bb9 | 12096 | /* |
ccff286d IM |
12097 | * Do not allow a recursive hierarchy (this new sibling |
12098 | * becoming part of another group-sibling): | |
12099 | */ | |
12100 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 12101 | goto err_context; |
34f43927 PZ |
12102 | |
12103 | /* All events in a group should have the same clock */ | |
12104 | if (group_leader->clock != event->clock) | |
12105 | goto err_context; | |
12106 | ||
ccff286d | 12107 | /* |
64aee2a9 MR |
12108 | * Make sure we're both events for the same CPU; |
12109 | * grouping events for different CPUs is broken; since | |
12110 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 12111 | */ |
64aee2a9 MR |
12112 | if (group_leader->cpu != event->cpu) |
12113 | goto err_context; | |
c3c87e77 | 12114 | |
64aee2a9 MR |
12115 | /* |
12116 | * Make sure we're both on the same task, or both | |
12117 | * per-CPU events. | |
12118 | */ | |
12119 | if (group_leader->ctx->task != ctx->task) | |
12120 | goto err_context; | |
12121 | ||
12122 | /* | |
12123 | * Do not allow to attach to a group in a different task | |
12124 | * or CPU context. If we're moving SW events, we'll fix | |
12125 | * this up later, so allow that. | |
12126 | */ | |
12127 | if (!move_group && group_leader->ctx != ctx) | |
12128 | goto err_context; | |
b04243ef | 12129 | |
3b6f9e5c PM |
12130 | /* |
12131 | * Only a group leader can be exclusive or pinned | |
12132 | */ | |
0d48696f | 12133 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 12134 | goto err_context; |
ac9721f3 PZ |
12135 | } |
12136 | ||
12137 | if (output_event) { | |
12138 | err = perf_event_set_output(event, output_event); | |
12139 | if (err) | |
c3f00c70 | 12140 | goto err_context; |
ac9721f3 | 12141 | } |
0793a61d | 12142 | |
a21b0b35 YD |
12143 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
12144 | f_flags); | |
ea635c64 AV |
12145 | if (IS_ERR(event_file)) { |
12146 | err = PTR_ERR(event_file); | |
201c2f85 | 12147 | event_file = NULL; |
c3f00c70 | 12148 | goto err_context; |
ea635c64 | 12149 | } |
9b51f66d | 12150 | |
78af4dc9 | 12151 | if (task) { |
d01e7f10 | 12152 | err = down_read_interruptible(&task->signal->exec_update_lock); |
78af4dc9 | 12153 | if (err) |
12154 | goto err_file; | |
12155 | ||
12156 | /* | |
12157 | * Preserve ptrace permission check for backwards compatibility. | |
12158 | * | |
d01e7f10 | 12159 | * We must hold exec_update_lock across this and any potential |
78af4dc9 | 12160 | * perf_install_in_context() call for this new event to |
12161 | * serialize against exec() altering our credentials (and the | |
12162 | * perf_event_exit_task() that could imply). | |
12163 | */ | |
12164 | err = -EACCES; | |
12165 | if (!perfmon_capable() && !ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
12166 | goto err_cred; | |
12167 | } | |
12168 | ||
b04243ef | 12169 | if (move_group) { |
321027c1 PZ |
12170 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
12171 | ||
84c4e620 PZ |
12172 | if (gctx->task == TASK_TOMBSTONE) { |
12173 | err = -ESRCH; | |
12174 | goto err_locked; | |
12175 | } | |
321027c1 PZ |
12176 | |
12177 | /* | |
12178 | * Check if we raced against another sys_perf_event_open() call | |
12179 | * moving the software group underneath us. | |
12180 | */ | |
12181 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
12182 | /* | |
12183 | * If someone moved the group out from under us, check | |
12184 | * if this new event wound up on the same ctx, if so | |
12185 | * its the regular !move_group case, otherwise fail. | |
12186 | */ | |
12187 | if (gctx != ctx) { | |
12188 | err = -EINVAL; | |
12189 | goto err_locked; | |
12190 | } else { | |
12191 | perf_event_ctx_unlock(group_leader, gctx); | |
12192 | move_group = 0; | |
12193 | } | |
12194 | } | |
8a58ddae AS |
12195 | |
12196 | /* | |
12197 | * Failure to create exclusive events returns -EBUSY. | |
12198 | */ | |
12199 | err = -EBUSY; | |
12200 | if (!exclusive_event_installable(group_leader, ctx)) | |
12201 | goto err_locked; | |
12202 | ||
12203 | for_each_sibling_event(sibling, group_leader) { | |
12204 | if (!exclusive_event_installable(sibling, ctx)) | |
12205 | goto err_locked; | |
12206 | } | |
f55fc2a5 PZ |
12207 | } else { |
12208 | mutex_lock(&ctx->mutex); | |
12209 | } | |
12210 | ||
84c4e620 PZ |
12211 | if (ctx->task == TASK_TOMBSTONE) { |
12212 | err = -ESRCH; | |
12213 | goto err_locked; | |
12214 | } | |
12215 | ||
a723968c PZ |
12216 | if (!perf_event_validate_size(event)) { |
12217 | err = -E2BIG; | |
12218 | goto err_locked; | |
12219 | } | |
12220 | ||
a63fbed7 TG |
12221 | if (!task) { |
12222 | /* | |
12223 | * Check if the @cpu we're creating an event for is online. | |
12224 | * | |
12225 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12226 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12227 | */ | |
12228 | struct perf_cpu_context *cpuctx = | |
12229 | container_of(ctx, struct perf_cpu_context, ctx); | |
12230 | ||
12231 | if (!cpuctx->online) { | |
12232 | err = -ENODEV; | |
12233 | goto err_locked; | |
12234 | } | |
12235 | } | |
12236 | ||
da9ec3d3 MR |
12237 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
12238 | err = -EINVAL; | |
ab43762e | 12239 | goto err_locked; |
da9ec3d3 | 12240 | } |
a63fbed7 | 12241 | |
f55fc2a5 PZ |
12242 | /* |
12243 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
12244 | * because we need to serialize with concurrent event creation. | |
12245 | */ | |
12246 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
12247 | err = -EBUSY; |
12248 | goto err_locked; | |
12249 | } | |
f63a8daa | 12250 | |
f55fc2a5 PZ |
12251 | WARN_ON_ONCE(ctx->parent_ctx); |
12252 | ||
79c9ce57 PZ |
12253 | /* |
12254 | * This is the point on no return; we cannot fail hereafter. This is | |
12255 | * where we start modifying current state. | |
12256 | */ | |
12257 | ||
f55fc2a5 | 12258 | if (move_group) { |
f63a8daa PZ |
12259 | /* |
12260 | * See perf_event_ctx_lock() for comments on the details | |
12261 | * of swizzling perf_event::ctx. | |
12262 | */ | |
45a0e07a | 12263 | perf_remove_from_context(group_leader, 0); |
279b5165 | 12264 | put_ctx(gctx); |
0231bb53 | 12265 | |
edb39592 | 12266 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 12267 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
12268 | put_ctx(gctx); |
12269 | } | |
b04243ef | 12270 | |
f63a8daa PZ |
12271 | /* |
12272 | * Wait for everybody to stop referencing the events through | |
12273 | * the old lists, before installing it on new lists. | |
12274 | */ | |
0cda4c02 | 12275 | synchronize_rcu(); |
f63a8daa | 12276 | |
8f95b435 PZI |
12277 | /* |
12278 | * Install the group siblings before the group leader. | |
12279 | * | |
12280 | * Because a group leader will try and install the entire group | |
12281 | * (through the sibling list, which is still in-tact), we can | |
12282 | * end up with siblings installed in the wrong context. | |
12283 | * | |
12284 | * By installing siblings first we NO-OP because they're not | |
12285 | * reachable through the group lists. | |
12286 | */ | |
edb39592 | 12287 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 12288 | perf_event__state_init(sibling); |
9fc81d87 | 12289 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
12290 | get_ctx(ctx); |
12291 | } | |
8f95b435 PZI |
12292 | |
12293 | /* | |
12294 | * Removing from the context ends up with disabled | |
12295 | * event. What we want here is event in the initial | |
12296 | * startup state, ready to be add into new context. | |
12297 | */ | |
12298 | perf_event__state_init(group_leader); | |
12299 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
12300 | get_ctx(ctx); | |
bed5b25a AS |
12301 | } |
12302 | ||
f73e22ab PZ |
12303 | /* |
12304 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
12305 | * that we're serialized against further additions and before | |
12306 | * perf_install_in_context() which is the point the event is active and | |
12307 | * can use these values. | |
12308 | */ | |
12309 | perf_event__header_size(event); | |
12310 | perf_event__id_header_size(event); | |
12311 | ||
78cd2c74 PZ |
12312 | event->owner = current; |
12313 | ||
e2d37cd2 | 12314 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12315 | perf_unpin_context(ctx); |
f63a8daa | 12316 | |
f55fc2a5 | 12317 | if (move_group) |
321027c1 | 12318 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 12319 | mutex_unlock(&ctx->mutex); |
9b51f66d | 12320 | |
79c9ce57 | 12321 | if (task) { |
f7cfd871 | 12322 | up_read(&task->signal->exec_update_lock); |
79c9ce57 PZ |
12323 | put_task_struct(task); |
12324 | } | |
12325 | ||
cdd6c482 IM |
12326 | mutex_lock(¤t->perf_event_mutex); |
12327 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
12328 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 12329 | |
8a49542c PZ |
12330 | /* |
12331 | * Drop the reference on the group_event after placing the | |
12332 | * new event on the sibling_list. This ensures destruction | |
12333 | * of the group leader will find the pointer to itself in | |
12334 | * perf_group_detach(). | |
12335 | */ | |
2903ff01 | 12336 | fdput(group); |
ea635c64 AV |
12337 | fd_install(event_fd, event_file); |
12338 | return event_fd; | |
0793a61d | 12339 | |
f55fc2a5 PZ |
12340 | err_locked: |
12341 | if (move_group) | |
321027c1 | 12342 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 | 12343 | mutex_unlock(&ctx->mutex); |
78af4dc9 | 12344 | err_cred: |
12345 | if (task) | |
d01e7f10 | 12346 | up_read(&task->signal->exec_update_lock); |
78af4dc9 | 12347 | err_file: |
f55fc2a5 | 12348 | fput(event_file); |
c3f00c70 | 12349 | err_context: |
fe4b04fa | 12350 | perf_unpin_context(ctx); |
ea635c64 | 12351 | put_ctx(ctx); |
c6be5a5c | 12352 | err_alloc: |
13005627 PZ |
12353 | /* |
12354 | * If event_file is set, the fput() above will have called ->release() | |
12355 | * and that will take care of freeing the event. | |
12356 | */ | |
12357 | if (!event_file) | |
12358 | free_event(event); | |
1f4ee503 | 12359 | err_task: |
e7d0bc04 PZ |
12360 | if (task) |
12361 | put_task_struct(task); | |
89a1e187 | 12362 | err_group_fd: |
2903ff01 | 12363 | fdput(group); |
ea635c64 AV |
12364 | err_fd: |
12365 | put_unused_fd(event_fd); | |
dc86cabe | 12366 | return err; |
0793a61d TG |
12367 | } |
12368 | ||
fb0459d7 AV |
12369 | /** |
12370 | * perf_event_create_kernel_counter | |
12371 | * | |
12372 | * @attr: attributes of the counter to create | |
12373 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 12374 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
12375 | */ |
12376 | struct perf_event * | |
12377 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 12378 | struct task_struct *task, |
4dc0da86 AK |
12379 | perf_overflow_handler_t overflow_handler, |
12380 | void *context) | |
fb0459d7 | 12381 | { |
fb0459d7 | 12382 | struct perf_event_context *ctx; |
c3f00c70 | 12383 | struct perf_event *event; |
fb0459d7 | 12384 | int err; |
d859e29f | 12385 | |
dce5affb AS |
12386 | /* |
12387 | * Grouping is not supported for kernel events, neither is 'AUX', | |
12388 | * make sure the caller's intentions are adjusted. | |
12389 | */ | |
12390 | if (attr->aux_output) | |
12391 | return ERR_PTR(-EINVAL); | |
12392 | ||
4dc0da86 | 12393 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 12394 | overflow_handler, context, -1); |
c3f00c70 PZ |
12395 | if (IS_ERR(event)) { |
12396 | err = PTR_ERR(event); | |
12397 | goto err; | |
12398 | } | |
d859e29f | 12399 | |
f8697762 | 12400 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 12401 | event->owner = TASK_TOMBSTONE; |
f8697762 | 12402 | |
f25d8ba9 AS |
12403 | /* |
12404 | * Get the target context (task or percpu): | |
12405 | */ | |
4af57ef2 | 12406 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
12407 | if (IS_ERR(ctx)) { |
12408 | err = PTR_ERR(ctx); | |
c3f00c70 | 12409 | goto err_free; |
d859e29f | 12410 | } |
fb0459d7 | 12411 | |
fb0459d7 AV |
12412 | WARN_ON_ONCE(ctx->parent_ctx); |
12413 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
12414 | if (ctx->task == TASK_TOMBSTONE) { |
12415 | err = -ESRCH; | |
12416 | goto err_unlock; | |
12417 | } | |
12418 | ||
a63fbed7 TG |
12419 | if (!task) { |
12420 | /* | |
12421 | * Check if the @cpu we're creating an event for is online. | |
12422 | * | |
12423 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12424 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12425 | */ | |
12426 | struct perf_cpu_context *cpuctx = | |
12427 | container_of(ctx, struct perf_cpu_context, ctx); | |
12428 | if (!cpuctx->online) { | |
12429 | err = -ENODEV; | |
12430 | goto err_unlock; | |
12431 | } | |
12432 | } | |
12433 | ||
bed5b25a | 12434 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 12435 | err = -EBUSY; |
84c4e620 | 12436 | goto err_unlock; |
bed5b25a AS |
12437 | } |
12438 | ||
4ce54af8 | 12439 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12440 | perf_unpin_context(ctx); |
fb0459d7 AV |
12441 | mutex_unlock(&ctx->mutex); |
12442 | ||
fb0459d7 AV |
12443 | return event; |
12444 | ||
84c4e620 PZ |
12445 | err_unlock: |
12446 | mutex_unlock(&ctx->mutex); | |
12447 | perf_unpin_context(ctx); | |
12448 | put_ctx(ctx); | |
c3f00c70 PZ |
12449 | err_free: |
12450 | free_event(event); | |
12451 | err: | |
c6567f64 | 12452 | return ERR_PTR(err); |
9b51f66d | 12453 | } |
fb0459d7 | 12454 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 12455 | |
0cda4c02 YZ |
12456 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
12457 | { | |
12458 | struct perf_event_context *src_ctx; | |
12459 | struct perf_event_context *dst_ctx; | |
12460 | struct perf_event *event, *tmp; | |
12461 | LIST_HEAD(events); | |
12462 | ||
12463 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
12464 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
12465 | ||
f63a8daa PZ |
12466 | /* |
12467 | * See perf_event_ctx_lock() for comments on the details | |
12468 | * of swizzling perf_event::ctx. | |
12469 | */ | |
12470 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
12471 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12472 | event_entry) { | |
45a0e07a | 12473 | perf_remove_from_context(event, 0); |
9a545de0 | 12474 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12475 | put_ctx(src_ctx); |
9886167d | 12476 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12477 | } |
0cda4c02 | 12478 | |
8f95b435 PZI |
12479 | /* |
12480 | * Wait for the events to quiesce before re-instating them. | |
12481 | */ | |
0cda4c02 YZ |
12482 | synchronize_rcu(); |
12483 | ||
8f95b435 PZI |
12484 | /* |
12485 | * Re-instate events in 2 passes. | |
12486 | * | |
12487 | * Skip over group leaders and only install siblings on this first | |
12488 | * pass, siblings will not get enabled without a leader, however a | |
12489 | * leader will enable its siblings, even if those are still on the old | |
12490 | * context. | |
12491 | */ | |
12492 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12493 | if (event->group_leader == event) | |
12494 | continue; | |
12495 | ||
12496 | list_del(&event->migrate_entry); | |
12497 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12498 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12499 | account_event_cpu(event, dst_cpu); | |
12500 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12501 | get_ctx(dst_ctx); | |
12502 | } | |
12503 | ||
12504 | /* | |
12505 | * Once all the siblings are setup properly, install the group leaders | |
12506 | * to make it go. | |
12507 | */ | |
9886167d PZ |
12508 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12509 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12510 | if (event->state >= PERF_EVENT_STATE_OFF) |
12511 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12512 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12513 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12514 | get_ctx(dst_ctx); | |
12515 | } | |
12516 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12517 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12518 | } |
12519 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12520 | ||
ef54c1a4 | 12521 | static void sync_child_event(struct perf_event *child_event) |
d859e29f | 12522 | { |
cdd6c482 | 12523 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12524 | u64 child_val; |
d859e29f | 12525 | |
ef54c1a4 PZ |
12526 | if (child_event->attr.inherit_stat) { |
12527 | struct task_struct *task = child_event->ctx->task; | |
12528 | ||
12529 | if (task && task != TASK_TOMBSTONE) | |
12530 | perf_event_read_event(child_event, task); | |
12531 | } | |
38b200d6 | 12532 | |
b5e58793 | 12533 | child_val = perf_event_count(child_event); |
d859e29f PM |
12534 | |
12535 | /* | |
12536 | * Add back the child's count to the parent's count: | |
12537 | */ | |
a6e6dea6 | 12538 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12539 | atomic64_add(child_event->total_time_enabled, |
12540 | &parent_event->child_total_time_enabled); | |
12541 | atomic64_add(child_event->total_time_running, | |
12542 | &parent_event->child_total_time_running); | |
d859e29f PM |
12543 | } |
12544 | ||
9b51f66d | 12545 | static void |
ef54c1a4 | 12546 | perf_event_exit_event(struct perf_event *event, struct perf_event_context *ctx) |
9b51f66d | 12547 | { |
ef54c1a4 PZ |
12548 | struct perf_event *parent_event = event->parent; |
12549 | unsigned long detach_flags = 0; | |
8ba289b8 | 12550 | |
ef54c1a4 PZ |
12551 | if (parent_event) { |
12552 | /* | |
12553 | * Do not destroy the 'original' grouping; because of the | |
12554 | * context switch optimization the original events could've | |
12555 | * ended up in a random child task. | |
12556 | * | |
12557 | * If we were to destroy the original group, all group related | |
12558 | * operations would cease to function properly after this | |
12559 | * random child dies. | |
12560 | * | |
12561 | * Do destroy all inherited groups, we don't care about those | |
12562 | * and being thorough is better. | |
12563 | */ | |
12564 | detach_flags = DETACH_GROUP | DETACH_CHILD; | |
12565 | mutex_lock(&parent_event->child_mutex); | |
12566 | } | |
32132a3d | 12567 | |
ef54c1a4 PZ |
12568 | perf_remove_from_context(event, detach_flags); |
12569 | ||
12570 | raw_spin_lock_irq(&ctx->lock); | |
12571 | if (event->state > PERF_EVENT_STATE_EXIT) | |
12572 | perf_event_set_state(event, PERF_EVENT_STATE_EXIT); | |
12573 | raw_spin_unlock_irq(&ctx->lock); | |
0cc0c027 | 12574 | |
9b51f66d | 12575 | /* |
ef54c1a4 | 12576 | * Child events can be freed. |
9b51f66d | 12577 | */ |
ef54c1a4 PZ |
12578 | if (parent_event) { |
12579 | mutex_unlock(&parent_event->child_mutex); | |
12580 | /* | |
12581 | * Kick perf_poll() for is_event_hup(); | |
12582 | */ | |
12583 | perf_event_wakeup(parent_event); | |
12584 | free_event(event); | |
12585 | put_event(parent_event); | |
8ba289b8 | 12586 | return; |
4bcf349a | 12587 | } |
8ba289b8 PZ |
12588 | |
12589 | /* | |
ef54c1a4 | 12590 | * Parent events are governed by their filedesc, retain them. |
8ba289b8 | 12591 | */ |
ef54c1a4 | 12592 | perf_event_wakeup(event); |
9b51f66d IM |
12593 | } |
12594 | ||
8dc85d54 | 12595 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12596 | { |
211de6eb | 12597 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12598 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12599 | |
12600 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12601 | |
6a3351b6 | 12602 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12603 | if (!child_ctx) |
9b51f66d IM |
12604 | return; |
12605 | ||
ad3a37de | 12606 | /* |
6a3351b6 PZ |
12607 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12608 | * ctx::mutex over the entire thing. This serializes against almost | |
12609 | * everything that wants to access the ctx. | |
12610 | * | |
12611 | * The exception is sys_perf_event_open() / | |
12612 | * perf_event_create_kernel_count() which does find_get_context() | |
12613 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12614 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12615 | */ |
6a3351b6 | 12616 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12617 | |
12618 | /* | |
6a3351b6 PZ |
12619 | * In a single ctx::lock section, de-schedule the events and detach the |
12620 | * context from the task such that we cannot ever get it scheduled back | |
12621 | * in. | |
c93f7669 | 12622 | */ |
6a3351b6 | 12623 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12624 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12625 | |
71a851b4 | 12626 | /* |
63b6da39 PZ |
12627 | * Now that the context is inactive, destroy the task <-> ctx relation |
12628 | * and mark the context dead. | |
71a851b4 | 12629 | */ |
63b6da39 PZ |
12630 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12631 | put_ctx(child_ctx); /* cannot be last */ | |
12632 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12633 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12634 | |
211de6eb | 12635 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12636 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12637 | |
211de6eb PZ |
12638 | if (clone_ctx) |
12639 | put_ctx(clone_ctx); | |
4a1c0f26 | 12640 | |
9f498cc5 | 12641 | /* |
cdd6c482 IM |
12642 | * Report the task dead after unscheduling the events so that we |
12643 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12644 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12645 | */ |
cdd6c482 | 12646 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12647 | |
ebf905fc | 12648 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
ef54c1a4 | 12649 | perf_event_exit_event(child_event, child_ctx); |
8bc20959 | 12650 | |
a63eaf34 PM |
12651 | mutex_unlock(&child_ctx->mutex); |
12652 | ||
12653 | put_ctx(child_ctx); | |
9b51f66d IM |
12654 | } |
12655 | ||
8dc85d54 PZ |
12656 | /* |
12657 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12658 | * |
f7cfd871 | 12659 | * Can be called with exec_update_lock held when called from |
96ecee29 | 12660 | * setup_new_exec(). |
8dc85d54 PZ |
12661 | */ |
12662 | void perf_event_exit_task(struct task_struct *child) | |
12663 | { | |
8882135b | 12664 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12665 | int ctxn; |
12666 | ||
8882135b PZ |
12667 | mutex_lock(&child->perf_event_mutex); |
12668 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12669 | owner_entry) { | |
12670 | list_del_init(&event->owner_entry); | |
12671 | ||
12672 | /* | |
12673 | * Ensure the list deletion is visible before we clear | |
12674 | * the owner, closes a race against perf_release() where | |
12675 | * we need to serialize on the owner->perf_event_mutex. | |
12676 | */ | |
f47c02c0 | 12677 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12678 | } |
12679 | mutex_unlock(&child->perf_event_mutex); | |
12680 | ||
8dc85d54 PZ |
12681 | for_each_task_context_nr(ctxn) |
12682 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12683 | |
12684 | /* | |
12685 | * The perf_event_exit_task_context calls perf_event_task | |
12686 | * with child's task_ctx, which generates EXIT events for | |
12687 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12688 | * At this point we need to send EXIT events to cpu contexts. | |
12689 | */ | |
12690 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12691 | } |
12692 | ||
889ff015 FW |
12693 | static void perf_free_event(struct perf_event *event, |
12694 | struct perf_event_context *ctx) | |
12695 | { | |
12696 | struct perf_event *parent = event->parent; | |
12697 | ||
12698 | if (WARN_ON_ONCE(!parent)) | |
12699 | return; | |
12700 | ||
12701 | mutex_lock(&parent->child_mutex); | |
12702 | list_del_init(&event->child_list); | |
12703 | mutex_unlock(&parent->child_mutex); | |
12704 | ||
a6fa941d | 12705 | put_event(parent); |
889ff015 | 12706 | |
652884fe | 12707 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12708 | perf_group_detach(event); |
889ff015 | 12709 | list_del_event(event, ctx); |
652884fe | 12710 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12711 | free_event(event); |
12712 | } | |
12713 | ||
bbbee908 | 12714 | /* |
1cf8dfe8 PZ |
12715 | * Free a context as created by inheritance by perf_event_init_task() below, |
12716 | * used by fork() in case of fail. | |
652884fe | 12717 | * |
1cf8dfe8 PZ |
12718 | * Even though the task has never lived, the context and events have been |
12719 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12720 | */ |
cdd6c482 | 12721 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12722 | { |
8dc85d54 | 12723 | struct perf_event_context *ctx; |
cdd6c482 | 12724 | struct perf_event *event, *tmp; |
8dc85d54 | 12725 | int ctxn; |
bbbee908 | 12726 | |
8dc85d54 PZ |
12727 | for_each_task_context_nr(ctxn) { |
12728 | ctx = task->perf_event_ctxp[ctxn]; | |
12729 | if (!ctx) | |
12730 | continue; | |
bbbee908 | 12731 | |
8dc85d54 | 12732 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12733 | raw_spin_lock_irq(&ctx->lock); |
12734 | /* | |
12735 | * Destroy the task <-> ctx relation and mark the context dead. | |
12736 | * | |
12737 | * This is important because even though the task hasn't been | |
12738 | * exposed yet the context has been (through child_list). | |
12739 | */ | |
12740 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12741 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12742 | put_task_struct(task); /* cannot be last */ | |
12743 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12744 | |
15121c78 | 12745 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12746 | perf_free_event(event, ctx); |
bbbee908 | 12747 | |
8dc85d54 | 12748 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12749 | |
12750 | /* | |
12751 | * perf_event_release_kernel() could've stolen some of our | |
12752 | * child events and still have them on its free_list. In that | |
12753 | * case we must wait for these events to have been freed (in | |
12754 | * particular all their references to this task must've been | |
12755 | * dropped). | |
12756 | * | |
12757 | * Without this copy_process() will unconditionally free this | |
12758 | * task (irrespective of its reference count) and | |
12759 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12760 | * use-after-free. | |
12761 | * | |
12762 | * Wait for all events to drop their context reference. | |
12763 | */ | |
12764 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12765 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12766 | } |
889ff015 FW |
12767 | } |
12768 | ||
4e231c79 PZ |
12769 | void perf_event_delayed_put(struct task_struct *task) |
12770 | { | |
12771 | int ctxn; | |
12772 | ||
12773 | for_each_task_context_nr(ctxn) | |
12774 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12775 | } | |
12776 | ||
e03e7ee3 | 12777 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12778 | { |
02e5ad97 | 12779 | struct file *file = fget(fd); |
e03e7ee3 AS |
12780 | if (!file) |
12781 | return ERR_PTR(-EBADF); | |
ffe8690c | 12782 | |
e03e7ee3 AS |
12783 | if (file->f_op != &perf_fops) { |
12784 | fput(file); | |
12785 | return ERR_PTR(-EBADF); | |
12786 | } | |
ffe8690c | 12787 | |
e03e7ee3 | 12788 | return file; |
ffe8690c KX |
12789 | } |
12790 | ||
f8d959a5 YS |
12791 | const struct perf_event *perf_get_event(struct file *file) |
12792 | { | |
12793 | if (file->f_op != &perf_fops) | |
12794 | return ERR_PTR(-EINVAL); | |
12795 | ||
12796 | return file->private_data; | |
12797 | } | |
12798 | ||
ffe8690c KX |
12799 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12800 | { | |
12801 | if (!event) | |
12802 | return ERR_PTR(-EINVAL); | |
12803 | ||
12804 | return &event->attr; | |
12805 | } | |
12806 | ||
97dee4f3 | 12807 | /* |
788faab7 | 12808 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12809 | * |
12810 | * Returns: | |
12811 | * - valid pointer on success | |
12812 | * - NULL for orphaned events | |
12813 | * - IS_ERR() on error | |
97dee4f3 PZ |
12814 | */ |
12815 | static struct perf_event * | |
12816 | inherit_event(struct perf_event *parent_event, | |
12817 | struct task_struct *parent, | |
12818 | struct perf_event_context *parent_ctx, | |
12819 | struct task_struct *child, | |
12820 | struct perf_event *group_leader, | |
12821 | struct perf_event_context *child_ctx) | |
12822 | { | |
8ca2bd41 | 12823 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12824 | struct perf_event *child_event; |
cee010ec | 12825 | unsigned long flags; |
97dee4f3 PZ |
12826 | |
12827 | /* | |
12828 | * Instead of creating recursive hierarchies of events, | |
12829 | * we link inherited events back to the original parent, | |
12830 | * which has a filp for sure, which we use as the reference | |
12831 | * count: | |
12832 | */ | |
12833 | if (parent_event->parent) | |
12834 | parent_event = parent_event->parent; | |
12835 | ||
12836 | child_event = perf_event_alloc(&parent_event->attr, | |
12837 | parent_event->cpu, | |
d580ff86 | 12838 | child, |
97dee4f3 | 12839 | group_leader, parent_event, |
79dff51e | 12840 | NULL, NULL, -1); |
97dee4f3 PZ |
12841 | if (IS_ERR(child_event)) |
12842 | return child_event; | |
a6fa941d | 12843 | |
313ccb96 JO |
12844 | |
12845 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12846 | !child_ctx->task_ctx_data) { | |
12847 | struct pmu *pmu = child_event->pmu; | |
12848 | ||
ff9ff926 | 12849 | child_ctx->task_ctx_data = alloc_task_ctx_data(pmu); |
313ccb96 JO |
12850 | if (!child_ctx->task_ctx_data) { |
12851 | free_event(child_event); | |
697d8778 | 12852 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12853 | } |
12854 | } | |
12855 | ||
c6e5b732 PZ |
12856 | /* |
12857 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12858 | * must be under the same lock in order to serialize against | |
12859 | * perf_event_release_kernel(), such that either we must observe | |
12860 | * is_orphaned_event() or they will observe us on the child_list. | |
12861 | */ | |
12862 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12863 | if (is_orphaned_event(parent_event) || |
12864 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12865 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12866 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12867 | free_event(child_event); |
12868 | return NULL; | |
12869 | } | |
12870 | ||
97dee4f3 PZ |
12871 | get_ctx(child_ctx); |
12872 | ||
12873 | /* | |
12874 | * Make the child state follow the state of the parent event, | |
12875 | * not its attr.disabled bit. We hold the parent's mutex, | |
12876 | * so we won't race with perf_event_{en, dis}able_family. | |
12877 | */ | |
1929def9 | 12878 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12879 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12880 | else | |
12881 | child_event->state = PERF_EVENT_STATE_OFF; | |
12882 | ||
12883 | if (parent_event->attr.freq) { | |
12884 | u64 sample_period = parent_event->hw.sample_period; | |
12885 | struct hw_perf_event *hwc = &child_event->hw; | |
12886 | ||
12887 | hwc->sample_period = sample_period; | |
12888 | hwc->last_period = sample_period; | |
12889 | ||
12890 | local64_set(&hwc->period_left, sample_period); | |
12891 | } | |
12892 | ||
12893 | child_event->ctx = child_ctx; | |
12894 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12895 | child_event->overflow_handler_context |
12896 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12897 | |
614b6780 TG |
12898 | /* |
12899 | * Precalculate sample_data sizes | |
12900 | */ | |
12901 | perf_event__header_size(child_event); | |
6844c09d | 12902 | perf_event__id_header_size(child_event); |
614b6780 | 12903 | |
97dee4f3 PZ |
12904 | /* |
12905 | * Link it up in the child's context: | |
12906 | */ | |
cee010ec | 12907 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12908 | add_event_to_ctx(child_event, child_ctx); |
ef54c1a4 | 12909 | child_event->attach_state |= PERF_ATTACH_CHILD; |
cee010ec | 12910 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12911 | |
97dee4f3 PZ |
12912 | /* |
12913 | * Link this into the parent event's child list | |
12914 | */ | |
97dee4f3 PZ |
12915 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12916 | mutex_unlock(&parent_event->child_mutex); | |
12917 | ||
12918 | return child_event; | |
12919 | } | |
12920 | ||
d8a8cfc7 PZ |
12921 | /* |
12922 | * Inherits an event group. | |
12923 | * | |
12924 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12925 | * This matches with perf_event_release_kernel() removing all child events. | |
12926 | * | |
12927 | * Returns: | |
12928 | * - 0 on success | |
12929 | * - <0 on error | |
12930 | */ | |
97dee4f3 PZ |
12931 | static int inherit_group(struct perf_event *parent_event, |
12932 | struct task_struct *parent, | |
12933 | struct perf_event_context *parent_ctx, | |
12934 | struct task_struct *child, | |
12935 | struct perf_event_context *child_ctx) | |
12936 | { | |
12937 | struct perf_event *leader; | |
12938 | struct perf_event *sub; | |
12939 | struct perf_event *child_ctr; | |
12940 | ||
12941 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12942 | child, NULL, child_ctx); | |
12943 | if (IS_ERR(leader)) | |
12944 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12945 | /* |
12946 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12947 | * case inherit_event() will create individual events, similar to what | |
12948 | * perf_group_detach() would do anyway. | |
12949 | */ | |
edb39592 | 12950 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12951 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12952 | child, leader, child_ctx); | |
12953 | if (IS_ERR(child_ctr)) | |
12954 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12955 | |
00496fe5 | 12956 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12957 | !perf_get_aux_event(child_ctr, leader)) |
12958 | return -EINVAL; | |
97dee4f3 PZ |
12959 | } |
12960 | return 0; | |
889ff015 FW |
12961 | } |
12962 | ||
d8a8cfc7 PZ |
12963 | /* |
12964 | * Creates the child task context and tries to inherit the event-group. | |
12965 | * | |
12966 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12967 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12968 | * consistent with perf_event_release_kernel() removing all child events. | |
12969 | * | |
12970 | * Returns: | |
12971 | * - 0 on success | |
12972 | * - <0 on error | |
12973 | */ | |
889ff015 FW |
12974 | static int |
12975 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12976 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12977 | struct task_struct *child, int ctxn, |
2b26f0aa | 12978 | u64 clone_flags, int *inherited_all) |
889ff015 FW |
12979 | { |
12980 | int ret; | |
8dc85d54 | 12981 | struct perf_event_context *child_ctx; |
889ff015 | 12982 | |
2b26f0aa | 12983 | if (!event->attr.inherit || |
97ba62b2 ME |
12984 | (event->attr.inherit_thread && !(clone_flags & CLONE_THREAD)) || |
12985 | /* Do not inherit if sigtrap and signal handlers were cleared. */ | |
12986 | (event->attr.sigtrap && (clone_flags & CLONE_CLEAR_SIGHAND))) { | |
889ff015 FW |
12987 | *inherited_all = 0; |
12988 | return 0; | |
bbbee908 PZ |
12989 | } |
12990 | ||
fe4b04fa | 12991 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12992 | if (!child_ctx) { |
12993 | /* | |
12994 | * This is executed from the parent task context, so | |
12995 | * inherit events that have been marked for cloning. | |
12996 | * First allocate and initialize a context for the | |
12997 | * child. | |
12998 | */ | |
734df5ab | 12999 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
13000 | if (!child_ctx) |
13001 | return -ENOMEM; | |
bbbee908 | 13002 | |
8dc85d54 | 13003 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
13004 | } |
13005 | ||
13006 | ret = inherit_group(event, parent, parent_ctx, | |
13007 | child, child_ctx); | |
13008 | ||
13009 | if (ret) | |
13010 | *inherited_all = 0; | |
13011 | ||
13012 | return ret; | |
bbbee908 PZ |
13013 | } |
13014 | ||
9b51f66d | 13015 | /* |
cdd6c482 | 13016 | * Initialize the perf_event context in task_struct |
9b51f66d | 13017 | */ |
2b26f0aa ME |
13018 | static int perf_event_init_context(struct task_struct *child, int ctxn, |
13019 | u64 clone_flags) | |
9b51f66d | 13020 | { |
889ff015 | 13021 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
13022 | struct perf_event_context *cloned_ctx; |
13023 | struct perf_event *event; | |
9b51f66d | 13024 | struct task_struct *parent = current; |
564c2b21 | 13025 | int inherited_all = 1; |
dddd3379 | 13026 | unsigned long flags; |
6ab423e0 | 13027 | int ret = 0; |
9b51f66d | 13028 | |
8dc85d54 | 13029 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
13030 | return 0; |
13031 | ||
ad3a37de | 13032 | /* |
25346b93 PM |
13033 | * If the parent's context is a clone, pin it so it won't get |
13034 | * swapped under us. | |
ad3a37de | 13035 | */ |
8dc85d54 | 13036 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
13037 | if (!parent_ctx) |
13038 | return 0; | |
25346b93 | 13039 | |
ad3a37de PM |
13040 | /* |
13041 | * No need to check if parent_ctx != NULL here; since we saw | |
13042 | * it non-NULL earlier, the only reason for it to become NULL | |
13043 | * is if we exit, and since we're currently in the middle of | |
13044 | * a fork we can't be exiting at the same time. | |
13045 | */ | |
ad3a37de | 13046 | |
9b51f66d IM |
13047 | /* |
13048 | * Lock the parent list. No need to lock the child - not PID | |
13049 | * hashed yet and not running, so nobody can access it. | |
13050 | */ | |
d859e29f | 13051 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
13052 | |
13053 | /* | |
13054 | * We dont have to disable NMIs - we are only looking at | |
13055 | * the list, not manipulating it: | |
13056 | */ | |
6e6804d2 | 13057 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 | 13058 | ret = inherit_task_group(event, parent, parent_ctx, |
2b26f0aa ME |
13059 | child, ctxn, clone_flags, |
13060 | &inherited_all); | |
889ff015 | 13061 | if (ret) |
e7cc4865 | 13062 | goto out_unlock; |
889ff015 | 13063 | } |
b93f7978 | 13064 | |
dddd3379 TG |
13065 | /* |
13066 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
13067 | * to allocations, but we need to prevent rotation because | |
13068 | * rotate_ctx() will change the list from interrupt context. | |
13069 | */ | |
13070 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
13071 | parent_ctx->rotate_disable = 1; | |
13072 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
13073 | ||
6e6804d2 | 13074 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 | 13075 | ret = inherit_task_group(event, parent, parent_ctx, |
2b26f0aa ME |
13076 | child, ctxn, clone_flags, |
13077 | &inherited_all); | |
889ff015 | 13078 | if (ret) |
e7cc4865 | 13079 | goto out_unlock; |
564c2b21 PM |
13080 | } |
13081 | ||
dddd3379 TG |
13082 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
13083 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 13084 | |
8dc85d54 | 13085 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 13086 | |
05cbaa28 | 13087 | if (child_ctx && inherited_all) { |
564c2b21 PM |
13088 | /* |
13089 | * Mark the child context as a clone of the parent | |
13090 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
13091 | * |
13092 | * Note that if the parent is a clone, the holding of | |
13093 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 13094 | */ |
c5ed5145 | 13095 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
13096 | if (cloned_ctx) { |
13097 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 13098 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
13099 | } else { |
13100 | child_ctx->parent_ctx = parent_ctx; | |
13101 | child_ctx->parent_gen = parent_ctx->generation; | |
13102 | } | |
13103 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
13104 | } |
13105 | ||
c5ed5145 | 13106 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 13107 | out_unlock: |
d859e29f | 13108 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 13109 | |
25346b93 | 13110 | perf_unpin_context(parent_ctx); |
fe4b04fa | 13111 | put_ctx(parent_ctx); |
ad3a37de | 13112 | |
6ab423e0 | 13113 | return ret; |
9b51f66d IM |
13114 | } |
13115 | ||
8dc85d54 PZ |
13116 | /* |
13117 | * Initialize the perf_event context in task_struct | |
13118 | */ | |
2b26f0aa | 13119 | int perf_event_init_task(struct task_struct *child, u64 clone_flags) |
8dc85d54 PZ |
13120 | { |
13121 | int ctxn, ret; | |
13122 | ||
8550d7cb ON |
13123 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
13124 | mutex_init(&child->perf_event_mutex); | |
13125 | INIT_LIST_HEAD(&child->perf_event_list); | |
13126 | ||
8dc85d54 | 13127 | for_each_task_context_nr(ctxn) { |
2b26f0aa | 13128 | ret = perf_event_init_context(child, ctxn, clone_flags); |
6c72e350 PZ |
13129 | if (ret) { |
13130 | perf_event_free_task(child); | |
8dc85d54 | 13131 | return ret; |
6c72e350 | 13132 | } |
8dc85d54 PZ |
13133 | } |
13134 | ||
13135 | return 0; | |
13136 | } | |
13137 | ||
220b140b PM |
13138 | static void __init perf_event_init_all_cpus(void) |
13139 | { | |
b28ab83c | 13140 | struct swevent_htable *swhash; |
220b140b | 13141 | int cpu; |
220b140b | 13142 | |
a63fbed7 TG |
13143 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
13144 | ||
220b140b | 13145 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
13146 | swhash = &per_cpu(swevent_htable, cpu); |
13147 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 13148 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
13149 | |
13150 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
13151 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 13152 | |
058fe1c0 DCC |
13153 | #ifdef CONFIG_CGROUP_PERF |
13154 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
13155 | #endif | |
a5398bff | 13156 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
13157 | } |
13158 | } | |
13159 | ||
d18bf422 | 13160 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 13161 | { |
108b02cf | 13162 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 13163 | |
b28ab83c | 13164 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 13165 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
13166 | struct swevent_hlist *hlist; |
13167 | ||
b28ab83c PZ |
13168 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
13169 | WARN_ON(!hlist); | |
13170 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 13171 | } |
b28ab83c | 13172 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
13173 | } |
13174 | ||
2965faa5 | 13175 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 13176 | static void __perf_event_exit_context(void *__info) |
0793a61d | 13177 | { |
108b02cf | 13178 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
13179 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
13180 | struct perf_event *event; | |
0793a61d | 13181 | |
fae3fde6 | 13182 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 13183 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 13184 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 13185 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 13186 | raw_spin_unlock(&ctx->lock); |
0793a61d | 13187 | } |
108b02cf PZ |
13188 | |
13189 | static void perf_event_exit_cpu_context(int cpu) | |
13190 | { | |
a63fbed7 | 13191 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
13192 | struct perf_event_context *ctx; |
13193 | struct pmu *pmu; | |
108b02cf | 13194 | |
a63fbed7 TG |
13195 | mutex_lock(&pmus_lock); |
13196 | list_for_each_entry(pmu, &pmus, entry) { | |
13197 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13198 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
13199 | |
13200 | mutex_lock(&ctx->mutex); | |
13201 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 13202 | cpuctx->online = 0; |
108b02cf PZ |
13203 | mutex_unlock(&ctx->mutex); |
13204 | } | |
a63fbed7 TG |
13205 | cpumask_clear_cpu(cpu, perf_online_mask); |
13206 | mutex_unlock(&pmus_lock); | |
108b02cf | 13207 | } |
00e16c3d TG |
13208 | #else |
13209 | ||
13210 | static void perf_event_exit_cpu_context(int cpu) { } | |
13211 | ||
13212 | #endif | |
108b02cf | 13213 | |
a63fbed7 TG |
13214 | int perf_event_init_cpu(unsigned int cpu) |
13215 | { | |
13216 | struct perf_cpu_context *cpuctx; | |
13217 | struct perf_event_context *ctx; | |
13218 | struct pmu *pmu; | |
13219 | ||
13220 | perf_swevent_init_cpu(cpu); | |
13221 | ||
13222 | mutex_lock(&pmus_lock); | |
13223 | cpumask_set_cpu(cpu, perf_online_mask); | |
13224 | list_for_each_entry(pmu, &pmus, entry) { | |
13225 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13226 | ctx = &cpuctx->ctx; | |
13227 | ||
13228 | mutex_lock(&ctx->mutex); | |
13229 | cpuctx->online = 1; | |
13230 | mutex_unlock(&ctx->mutex); | |
13231 | } | |
13232 | mutex_unlock(&pmus_lock); | |
13233 | ||
13234 | return 0; | |
13235 | } | |
13236 | ||
00e16c3d | 13237 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 13238 | { |
e3703f8c | 13239 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 13240 | return 0; |
0793a61d | 13241 | } |
0793a61d | 13242 | |
c277443c PZ |
13243 | static int |
13244 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
13245 | { | |
13246 | int cpu; | |
13247 | ||
13248 | for_each_online_cpu(cpu) | |
13249 | perf_event_exit_cpu(cpu); | |
13250 | ||
13251 | return NOTIFY_OK; | |
13252 | } | |
13253 | ||
13254 | /* | |
13255 | * Run the perf reboot notifier at the very last possible moment so that | |
13256 | * the generic watchdog code runs as long as possible. | |
13257 | */ | |
13258 | static struct notifier_block perf_reboot_notifier = { | |
13259 | .notifier_call = perf_reboot, | |
13260 | .priority = INT_MIN, | |
13261 | }; | |
13262 | ||
cdd6c482 | 13263 | void __init perf_event_init(void) |
0793a61d | 13264 | { |
3c502e7a JW |
13265 | int ret; |
13266 | ||
2e80a82a PZ |
13267 | idr_init(&pmu_idr); |
13268 | ||
220b140b | 13269 | perf_event_init_all_cpus(); |
b0a873eb | 13270 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
13271 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
13272 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
13273 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 13274 | perf_tp_register(); |
00e16c3d | 13275 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 13276 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
13277 | |
13278 | ret = init_hw_breakpoint(); | |
13279 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 13280 | |
bdacfaf2 NK |
13281 | perf_event_cache = KMEM_CACHE(perf_event, SLAB_PANIC); |
13282 | ||
b01c3a00 JO |
13283 | /* |
13284 | * Build time assertion that we keep the data_head at the intended | |
13285 | * location. IOW, validation we got the __reserved[] size right. | |
13286 | */ | |
13287 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
13288 | != 1024); | |
0793a61d | 13289 | } |
abe43400 | 13290 | |
fd979c01 CS |
13291 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
13292 | char *page) | |
13293 | { | |
13294 | struct perf_pmu_events_attr *pmu_attr = | |
13295 | container_of(attr, struct perf_pmu_events_attr, attr); | |
13296 | ||
13297 | if (pmu_attr->event_str) | |
13298 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
13299 | ||
13300 | return 0; | |
13301 | } | |
675965b0 | 13302 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 13303 | |
abe43400 PZ |
13304 | static int __init perf_event_sysfs_init(void) |
13305 | { | |
13306 | struct pmu *pmu; | |
13307 | int ret; | |
13308 | ||
13309 | mutex_lock(&pmus_lock); | |
13310 | ||
13311 | ret = bus_register(&pmu_bus); | |
13312 | if (ret) | |
13313 | goto unlock; | |
13314 | ||
13315 | list_for_each_entry(pmu, &pmus, entry) { | |
13316 | if (!pmu->name || pmu->type < 0) | |
13317 | continue; | |
13318 | ||
13319 | ret = pmu_dev_alloc(pmu); | |
13320 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
13321 | } | |
13322 | pmu_bus_running = 1; | |
13323 | ret = 0; | |
13324 | ||
13325 | unlock: | |
13326 | mutex_unlock(&pmus_lock); | |
13327 | ||
13328 | return ret; | |
13329 | } | |
13330 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
13331 | |
13332 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
13333 | static struct cgroup_subsys_state * |
13334 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
13335 | { |
13336 | struct perf_cgroup *jc; | |
e5d1367f | 13337 | |
1b15d055 | 13338 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
13339 | if (!jc) |
13340 | return ERR_PTR(-ENOMEM); | |
13341 | ||
e5d1367f SE |
13342 | jc->info = alloc_percpu(struct perf_cgroup_info); |
13343 | if (!jc->info) { | |
13344 | kfree(jc); | |
13345 | return ERR_PTR(-ENOMEM); | |
13346 | } | |
13347 | ||
e5d1367f SE |
13348 | return &jc->css; |
13349 | } | |
13350 | ||
eb95419b | 13351 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 13352 | { |
eb95419b TH |
13353 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
13354 | ||
e5d1367f SE |
13355 | free_percpu(jc->info); |
13356 | kfree(jc); | |
13357 | } | |
13358 | ||
96aaab68 NK |
13359 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
13360 | { | |
13361 | perf_event_cgroup(css->cgroup); | |
13362 | return 0; | |
13363 | } | |
13364 | ||
e5d1367f SE |
13365 | static int __perf_cgroup_move(void *info) |
13366 | { | |
13367 | struct task_struct *task = info; | |
ddaaf4e2 | 13368 | rcu_read_lock(); |
e5d1367f | 13369 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 13370 | rcu_read_unlock(); |
e5d1367f SE |
13371 | return 0; |
13372 | } | |
13373 | ||
1f7dd3e5 | 13374 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 13375 | { |
bb9d97b6 | 13376 | struct task_struct *task; |
1f7dd3e5 | 13377 | struct cgroup_subsys_state *css; |
bb9d97b6 | 13378 | |
1f7dd3e5 | 13379 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 13380 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
13381 | } |
13382 | ||
073219e9 | 13383 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
13384 | .css_alloc = perf_cgroup_css_alloc, |
13385 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 13386 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 13387 | .attach = perf_cgroup_attach, |
968ebff1 TH |
13388 | /* |
13389 | * Implicitly enable on dfl hierarchy so that perf events can | |
13390 | * always be filtered by cgroup2 path as long as perf_event | |
13391 | * controller is not mounted on a legacy hierarchy. | |
13392 | */ | |
13393 | .implicit_on_dfl = true, | |
8cfd8147 | 13394 | .threaded = true, |
e5d1367f SE |
13395 | }; |
13396 | #endif /* CONFIG_CGROUP_PERF */ |