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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> |
0793a61d | 56 | |
76369139 FW |
57 | #include "internal.h" |
58 | ||
4e193bd4 TB |
59 | #include <asm/irq_regs.h> |
60 | ||
272325c4 PZ |
61 | typedef int (*remote_function_f)(void *); |
62 | ||
fe4b04fa | 63 | struct remote_function_call { |
e7e7ee2e | 64 | struct task_struct *p; |
272325c4 | 65 | remote_function_f func; |
e7e7ee2e IM |
66 | void *info; |
67 | int ret; | |
fe4b04fa PZ |
68 | }; |
69 | ||
70 | static void remote_function(void *data) | |
71 | { | |
72 | struct remote_function_call *tfc = data; | |
73 | struct task_struct *p = tfc->p; | |
74 | ||
75 | if (p) { | |
0da4cf3e PZ |
76 | /* -EAGAIN */ |
77 | if (task_cpu(p) != smp_processor_id()) | |
78 | return; | |
79 | ||
80 | /* | |
81 | * Now that we're on right CPU with IRQs disabled, we can test | |
82 | * if we hit the right task without races. | |
83 | */ | |
84 | ||
85 | tfc->ret = -ESRCH; /* No such (running) process */ | |
86 | if (p != current) | |
fe4b04fa PZ |
87 | return; |
88 | } | |
89 | ||
90 | tfc->ret = tfc->func(tfc->info); | |
91 | } | |
92 | ||
93 | /** | |
94 | * task_function_call - call a function on the cpu on which a task runs | |
95 | * @p: the task to evaluate | |
96 | * @func: the function to be called | |
97 | * @info: the function call argument | |
98 | * | |
99 | * Calls the function @func when the task is currently running. This might | |
2ed6edd3 BR |
100 | * be on the current CPU, which just calls the function directly. This will |
101 | * retry due to any failures in smp_call_function_single(), such as if the | |
102 | * task_cpu() goes offline concurrently. | |
fe4b04fa | 103 | * |
6d6b8b9f | 104 | * returns @func return value or -ESRCH or -ENXIO when the process isn't running |
fe4b04fa PZ |
105 | */ |
106 | static int | |
272325c4 | 107 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
108 | { |
109 | struct remote_function_call data = { | |
e7e7ee2e IM |
110 | .p = p, |
111 | .func = func, | |
112 | .info = info, | |
0da4cf3e | 113 | .ret = -EAGAIN, |
fe4b04fa | 114 | }; |
0da4cf3e | 115 | int ret; |
fe4b04fa | 116 | |
2ed6edd3 BR |
117 | for (;;) { |
118 | ret = smp_call_function_single(task_cpu(p), remote_function, | |
119 | &data, 1); | |
6d6b8b9f KJ |
120 | if (!ret) |
121 | ret = data.ret; | |
2ed6edd3 BR |
122 | |
123 | if (ret != -EAGAIN) | |
124 | break; | |
125 | ||
126 | cond_resched(); | |
127 | } | |
fe4b04fa | 128 | |
0da4cf3e | 129 | return ret; |
fe4b04fa PZ |
130 | } |
131 | ||
132 | /** | |
133 | * cpu_function_call - call a function on the cpu | |
134 | * @func: the function to be called | |
135 | * @info: the function call argument | |
136 | * | |
137 | * Calls the function @func on the remote cpu. | |
138 | * | |
139 | * returns: @func return value or -ENXIO when the cpu is offline | |
140 | */ | |
272325c4 | 141 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
142 | { |
143 | struct remote_function_call data = { | |
e7e7ee2e IM |
144 | .p = NULL, |
145 | .func = func, | |
146 | .info = info, | |
147 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
148 | }; |
149 | ||
150 | smp_call_function_single(cpu, remote_function, &data, 1); | |
151 | ||
152 | return data.ret; | |
153 | } | |
154 | ||
fae3fde6 PZ |
155 | static inline struct perf_cpu_context * |
156 | __get_cpu_context(struct perf_event_context *ctx) | |
157 | { | |
158 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
159 | } | |
160 | ||
161 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
162 | struct perf_event_context *ctx) | |
0017960f | 163 | { |
fae3fde6 PZ |
164 | raw_spin_lock(&cpuctx->ctx.lock); |
165 | if (ctx) | |
166 | raw_spin_lock(&ctx->lock); | |
167 | } | |
168 | ||
169 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
170 | struct perf_event_context *ctx) | |
171 | { | |
172 | if (ctx) | |
173 | raw_spin_unlock(&ctx->lock); | |
174 | raw_spin_unlock(&cpuctx->ctx.lock); | |
175 | } | |
176 | ||
63b6da39 PZ |
177 | #define TASK_TOMBSTONE ((void *)-1L) |
178 | ||
179 | static bool is_kernel_event(struct perf_event *event) | |
180 | { | |
f47c02c0 | 181 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
182 | } |
183 | ||
39a43640 PZ |
184 | /* |
185 | * On task ctx scheduling... | |
186 | * | |
187 | * When !ctx->nr_events a task context will not be scheduled. This means | |
188 | * we can disable the scheduler hooks (for performance) without leaving | |
189 | * pending task ctx state. | |
190 | * | |
191 | * This however results in two special cases: | |
192 | * | |
193 | * - removing the last event from a task ctx; this is relatively straight | |
194 | * forward and is done in __perf_remove_from_context. | |
195 | * | |
196 | * - adding the first event to a task ctx; this is tricky because we cannot | |
197 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
198 | * See perf_install_in_context(). | |
199 | * | |
39a43640 PZ |
200 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
201 | */ | |
202 | ||
fae3fde6 PZ |
203 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
204 | struct perf_event_context *, void *); | |
205 | ||
206 | struct event_function_struct { | |
207 | struct perf_event *event; | |
208 | event_f func; | |
209 | void *data; | |
210 | }; | |
211 | ||
212 | static int event_function(void *info) | |
213 | { | |
214 | struct event_function_struct *efs = info; | |
215 | struct perf_event *event = efs->event; | |
0017960f | 216 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
217 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
218 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 219 | int ret = 0; |
fae3fde6 | 220 | |
16444645 | 221 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 222 | |
63b6da39 | 223 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
224 | /* |
225 | * Since we do the IPI call without holding ctx->lock things can have | |
226 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
227 | */ |
228 | if (ctx->task) { | |
63b6da39 | 229 | if (ctx->task != current) { |
0da4cf3e | 230 | ret = -ESRCH; |
63b6da39 PZ |
231 | goto unlock; |
232 | } | |
fae3fde6 | 233 | |
fae3fde6 PZ |
234 | /* |
235 | * We only use event_function_call() on established contexts, | |
236 | * and event_function() is only ever called when active (or | |
237 | * rather, we'll have bailed in task_function_call() or the | |
238 | * above ctx->task != current test), therefore we must have | |
239 | * ctx->is_active here. | |
240 | */ | |
241 | WARN_ON_ONCE(!ctx->is_active); | |
242 | /* | |
243 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
244 | * match. | |
245 | */ | |
63b6da39 PZ |
246 | WARN_ON_ONCE(task_ctx != ctx); |
247 | } else { | |
248 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 249 | } |
63b6da39 | 250 | |
fae3fde6 | 251 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 252 | unlock: |
fae3fde6 PZ |
253 | perf_ctx_unlock(cpuctx, task_ctx); |
254 | ||
63b6da39 | 255 | return ret; |
fae3fde6 PZ |
256 | } |
257 | ||
fae3fde6 | 258 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
259 | { |
260 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 261 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
262 | struct event_function_struct efs = { |
263 | .event = event, | |
264 | .func = func, | |
265 | .data = data, | |
266 | }; | |
0017960f | 267 | |
c97f4736 PZ |
268 | if (!event->parent) { |
269 | /* | |
270 | * If this is a !child event, we must hold ctx::mutex to | |
271 | * stabilize the the event->ctx relation. See | |
272 | * perf_event_ctx_lock(). | |
273 | */ | |
274 | lockdep_assert_held(&ctx->mutex); | |
275 | } | |
0017960f PZ |
276 | |
277 | if (!task) { | |
fae3fde6 | 278 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
279 | return; |
280 | } | |
281 | ||
63b6da39 PZ |
282 | if (task == TASK_TOMBSTONE) |
283 | return; | |
284 | ||
a096309b | 285 | again: |
fae3fde6 | 286 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
287 | return; |
288 | ||
289 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
290 | /* |
291 | * Reload the task pointer, it might have been changed by | |
292 | * a concurrent perf_event_context_sched_out(). | |
293 | */ | |
294 | task = ctx->task; | |
a096309b PZ |
295 | if (task == TASK_TOMBSTONE) { |
296 | raw_spin_unlock_irq(&ctx->lock); | |
297 | return; | |
0017960f | 298 | } |
a096309b PZ |
299 | if (ctx->is_active) { |
300 | raw_spin_unlock_irq(&ctx->lock); | |
301 | goto again; | |
302 | } | |
303 | func(event, NULL, ctx, data); | |
0017960f PZ |
304 | raw_spin_unlock_irq(&ctx->lock); |
305 | } | |
306 | ||
cca20946 PZ |
307 | /* |
308 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
309 | * are already disabled and we're on the right CPU. | |
310 | */ | |
311 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
312 | { | |
313 | struct perf_event_context *ctx = event->ctx; | |
314 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
315 | struct task_struct *task = READ_ONCE(ctx->task); | |
316 | struct perf_event_context *task_ctx = NULL; | |
317 | ||
16444645 | 318 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
319 | |
320 | if (task) { | |
321 | if (task == TASK_TOMBSTONE) | |
322 | return; | |
323 | ||
324 | task_ctx = ctx; | |
325 | } | |
326 | ||
327 | perf_ctx_lock(cpuctx, task_ctx); | |
328 | ||
329 | task = ctx->task; | |
330 | if (task == TASK_TOMBSTONE) | |
331 | goto unlock; | |
332 | ||
333 | if (task) { | |
334 | /* | |
335 | * We must be either inactive or active and the right task, | |
336 | * otherwise we're screwed, since we cannot IPI to somewhere | |
337 | * else. | |
338 | */ | |
339 | if (ctx->is_active) { | |
340 | if (WARN_ON_ONCE(task != current)) | |
341 | goto unlock; | |
342 | ||
343 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
344 | goto unlock; | |
345 | } | |
346 | } else { | |
347 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
348 | } | |
349 | ||
350 | func(event, cpuctx, ctx, data); | |
351 | unlock: | |
352 | perf_ctx_unlock(cpuctx, task_ctx); | |
353 | } | |
354 | ||
e5d1367f SE |
355 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
356 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
357 | PERF_FLAG_PID_CGROUP |\ |
358 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 359 | |
bce38cd5 SE |
360 | /* |
361 | * branch priv levels that need permission checks | |
362 | */ | |
363 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
364 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
365 | PERF_SAMPLE_BRANCH_HV) | |
366 | ||
0b3fcf17 SE |
367 | enum event_type_t { |
368 | EVENT_FLEXIBLE = 0x1, | |
369 | EVENT_PINNED = 0x2, | |
3cbaa590 | 370 | EVENT_TIME = 0x4, |
487f05e1 AS |
371 | /* see ctx_resched() for details */ |
372 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
373 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
374 | }; | |
375 | ||
e5d1367f SE |
376 | /* |
377 | * perf_sched_events : >0 events exist | |
378 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
379 | */ | |
9107c89e PZ |
380 | |
381 | static void perf_sched_delayed(struct work_struct *work); | |
382 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
383 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
384 | static DEFINE_MUTEX(perf_sched_mutex); | |
385 | static atomic_t perf_sched_count; | |
386 | ||
e5d1367f | 387 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
f008790a | 388 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 389 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 390 | |
cdd6c482 IM |
391 | static atomic_t nr_mmap_events __read_mostly; |
392 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 393 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 394 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 395 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 396 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 397 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 398 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 399 | static atomic_t nr_cgroup_events __read_mostly; |
e17d43b9 | 400 | static atomic_t nr_text_poke_events __read_mostly; |
9ee318a7 | 401 | |
108b02cf PZ |
402 | static LIST_HEAD(pmus); |
403 | static DEFINE_MUTEX(pmus_lock); | |
404 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 405 | static cpumask_var_t perf_online_mask; |
108b02cf | 406 | |
0764771d | 407 | /* |
cdd6c482 | 408 | * perf event paranoia level: |
0fbdea19 IM |
409 | * -1 - not paranoid at all |
410 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 411 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 412 | * 2 - disallow kernel profiling for unpriv |
04d76d75 | 413 | * 4 - disallow all unpriv perf event use |
0764771d | 414 | */ |
04d76d75 BH |
415 | #ifdef CONFIG_SECURITY_PERF_EVENTS_RESTRICT |
416 | int sysctl_perf_event_paranoid __read_mostly = PERF_SECURITY_MAX; | |
417 | #else | |
0161028b | 418 | int sysctl_perf_event_paranoid __read_mostly = 2; |
04d76d75 | 419 | #endif |
0764771d | 420 | |
20443384 FW |
421 | /* Minimum for 512 kiB + 1 user control page */ |
422 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
423 | |
424 | /* | |
cdd6c482 | 425 | * max perf event sample rate |
df58ab24 | 426 | */ |
14c63f17 DH |
427 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
428 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
429 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
430 | ||
431 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
432 | ||
433 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
434 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
435 | ||
d9494cb4 PZ |
436 | static int perf_sample_allowed_ns __read_mostly = |
437 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 438 | |
18ab2cd3 | 439 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
440 | { |
441 | u64 tmp = perf_sample_period_ns; | |
442 | ||
443 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
444 | tmp = div_u64(tmp, 100); |
445 | if (!tmp) | |
446 | tmp = 1; | |
447 | ||
448 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 449 | } |
163ec435 | 450 | |
8d5bce0c | 451 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 452 | |
163ec435 | 453 | int perf_proc_update_handler(struct ctl_table *table, int write, |
32927393 | 454 | void *buffer, size_t *lenp, loff_t *ppos) |
163ec435 | 455 | { |
1a51c5da SE |
456 | int ret; |
457 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
458 | /* |
459 | * If throttling is disabled don't allow the write: | |
460 | */ | |
1a51c5da | 461 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
462 | return -EINVAL; |
463 | ||
1a51c5da SE |
464 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
465 | if (ret || !write) | |
466 | return ret; | |
467 | ||
163ec435 | 468 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
469 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
470 | update_perf_cpu_limits(); | |
471 | ||
472 | return 0; | |
473 | } | |
474 | ||
475 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
476 | ||
477 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
32927393 | 478 | void *buffer, size_t *lenp, loff_t *ppos) |
14c63f17 | 479 | { |
1572e45a | 480 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
481 | |
482 | if (ret || !write) | |
483 | return ret; | |
484 | ||
b303e7c1 PZ |
485 | if (sysctl_perf_cpu_time_max_percent == 100 || |
486 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
487 | printk(KERN_WARNING |
488 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
489 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
490 | } else { | |
491 | update_perf_cpu_limits(); | |
492 | } | |
163ec435 PZ |
493 | |
494 | return 0; | |
495 | } | |
1ccd1549 | 496 | |
14c63f17 DH |
497 | /* |
498 | * perf samples are done in some very critical code paths (NMIs). | |
499 | * If they take too much CPU time, the system can lock up and not | |
500 | * get any real work done. This will drop the sample rate when | |
501 | * we detect that events are taking too long. | |
502 | */ | |
503 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 504 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 505 | |
91a612ee PZ |
506 | static u64 __report_avg; |
507 | static u64 __report_allowed; | |
508 | ||
6a02ad66 | 509 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 510 | { |
0d87d7ec | 511 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
512 | "perf: interrupt took too long (%lld > %lld), lowering " |
513 | "kernel.perf_event_max_sample_rate to %d\n", | |
514 | __report_avg, __report_allowed, | |
515 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
516 | } |
517 | ||
518 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
519 | ||
520 | void perf_sample_event_took(u64 sample_len_ns) | |
521 | { | |
91a612ee PZ |
522 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
523 | u64 running_len; | |
524 | u64 avg_len; | |
525 | u32 max; | |
14c63f17 | 526 | |
91a612ee | 527 | if (max_len == 0) |
14c63f17 DH |
528 | return; |
529 | ||
91a612ee PZ |
530 | /* Decay the counter by 1 average sample. */ |
531 | running_len = __this_cpu_read(running_sample_length); | |
532 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
533 | running_len += sample_len_ns; | |
534 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
535 | |
536 | /* | |
91a612ee PZ |
537 | * Note: this will be biased artifically low until we have |
538 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
539 | * from having to maintain a count. |
540 | */ | |
91a612ee PZ |
541 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
542 | if (avg_len <= max_len) | |
14c63f17 DH |
543 | return; |
544 | ||
91a612ee PZ |
545 | __report_avg = avg_len; |
546 | __report_allowed = max_len; | |
14c63f17 | 547 | |
91a612ee PZ |
548 | /* |
549 | * Compute a throttle threshold 25% below the current duration. | |
550 | */ | |
551 | avg_len += avg_len / 4; | |
552 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
553 | if (avg_len < max) | |
554 | max /= (u32)avg_len; | |
555 | else | |
556 | max = 1; | |
14c63f17 | 557 | |
91a612ee PZ |
558 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
559 | WRITE_ONCE(max_samples_per_tick, max); | |
560 | ||
561 | sysctl_perf_event_sample_rate = max * HZ; | |
562 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 563 | |
cd578abb | 564 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 565 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 566 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 567 | __report_avg, __report_allowed, |
cd578abb PZ |
568 | sysctl_perf_event_sample_rate); |
569 | } | |
14c63f17 DH |
570 | } |
571 | ||
cdd6c482 | 572 | static atomic64_t perf_event_id; |
a96bbc16 | 573 | |
0b3fcf17 SE |
574 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
575 | enum event_type_t event_type); | |
576 | ||
577 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
578 | enum event_type_t event_type, |
579 | struct task_struct *task); | |
580 | ||
581 | static void update_context_time(struct perf_event_context *ctx); | |
582 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 583 | |
cdd6c482 | 584 | void __weak perf_event_print_debug(void) { } |
0793a61d | 585 | |
84c79910 | 586 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 587 | { |
84c79910 | 588 | return "pmu"; |
0793a61d TG |
589 | } |
590 | ||
0b3fcf17 SE |
591 | static inline u64 perf_clock(void) |
592 | { | |
593 | return local_clock(); | |
594 | } | |
595 | ||
34f43927 PZ |
596 | static inline u64 perf_event_clock(struct perf_event *event) |
597 | { | |
598 | return event->clock(); | |
599 | } | |
600 | ||
0d3d73aa PZ |
601 | /* |
602 | * State based event timekeeping... | |
603 | * | |
604 | * The basic idea is to use event->state to determine which (if any) time | |
605 | * fields to increment with the current delta. This means we only need to | |
606 | * update timestamps when we change state or when they are explicitly requested | |
607 | * (read). | |
608 | * | |
609 | * Event groups make things a little more complicated, but not terribly so. The | |
610 | * rules for a group are that if the group leader is OFF the entire group is | |
611 | * OFF, irrespecive of what the group member states are. This results in | |
612 | * __perf_effective_state(). | |
613 | * | |
614 | * A futher ramification is that when a group leader flips between OFF and | |
615 | * !OFF, we need to update all group member times. | |
616 | * | |
617 | * | |
618 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
619 | * need to make sure the relevant context time is updated before we try and | |
620 | * update our timestamps. | |
621 | */ | |
622 | ||
623 | static __always_inline enum perf_event_state | |
624 | __perf_effective_state(struct perf_event *event) | |
625 | { | |
626 | struct perf_event *leader = event->group_leader; | |
627 | ||
628 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
629 | return leader->state; | |
630 | ||
631 | return event->state; | |
632 | } | |
633 | ||
634 | static __always_inline void | |
635 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
636 | { | |
637 | enum perf_event_state state = __perf_effective_state(event); | |
638 | u64 delta = now - event->tstamp; | |
639 | ||
640 | *enabled = event->total_time_enabled; | |
641 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
642 | *enabled += delta; | |
643 | ||
644 | *running = event->total_time_running; | |
645 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
646 | *running += delta; | |
647 | } | |
648 | ||
649 | static void perf_event_update_time(struct perf_event *event) | |
650 | { | |
651 | u64 now = perf_event_time(event); | |
652 | ||
653 | __perf_update_times(event, now, &event->total_time_enabled, | |
654 | &event->total_time_running); | |
655 | event->tstamp = now; | |
656 | } | |
657 | ||
658 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
659 | { | |
660 | struct perf_event *sibling; | |
661 | ||
edb39592 | 662 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
663 | perf_event_update_time(sibling); |
664 | } | |
665 | ||
666 | static void | |
667 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
668 | { | |
669 | if (event->state == state) | |
670 | return; | |
671 | ||
672 | perf_event_update_time(event); | |
673 | /* | |
674 | * If a group leader gets enabled/disabled all its siblings | |
675 | * are affected too. | |
676 | */ | |
677 | if ((event->state < 0) ^ (state < 0)) | |
678 | perf_event_update_sibling_time(event); | |
679 | ||
680 | WRITE_ONCE(event->state, state); | |
681 | } | |
682 | ||
e5d1367f SE |
683 | #ifdef CONFIG_CGROUP_PERF |
684 | ||
e5d1367f SE |
685 | static inline bool |
686 | perf_cgroup_match(struct perf_event *event) | |
687 | { | |
688 | struct perf_event_context *ctx = event->ctx; | |
689 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
690 | ||
ef824fa1 TH |
691 | /* @event doesn't care about cgroup */ |
692 | if (!event->cgrp) | |
693 | return true; | |
694 | ||
695 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
696 | if (!cpuctx->cgrp) | |
697 | return false; | |
698 | ||
699 | /* | |
700 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
701 | * also enabled for all its descendant cgroups. If @cpuctx's | |
702 | * cgroup is a descendant of @event's (the test covers identity | |
703 | * case), it's a match. | |
704 | */ | |
705 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
706 | event->cgrp->css.cgroup); | |
e5d1367f SE |
707 | } |
708 | ||
e5d1367f SE |
709 | static inline void perf_detach_cgroup(struct perf_event *event) |
710 | { | |
4e2ba650 | 711 | css_put(&event->cgrp->css); |
e5d1367f SE |
712 | event->cgrp = NULL; |
713 | } | |
714 | ||
715 | static inline int is_cgroup_event(struct perf_event *event) | |
716 | { | |
717 | return event->cgrp != NULL; | |
718 | } | |
719 | ||
720 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
721 | { | |
722 | struct perf_cgroup_info *t; | |
723 | ||
724 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
725 | return t->time; | |
726 | } | |
727 | ||
728 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
729 | { | |
730 | struct perf_cgroup_info *info; | |
731 | u64 now; | |
732 | ||
733 | now = perf_clock(); | |
734 | ||
735 | info = this_cpu_ptr(cgrp->info); | |
736 | ||
737 | info->time += now - info->timestamp; | |
738 | info->timestamp = now; | |
739 | } | |
740 | ||
741 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
742 | { | |
c917e0f2 SL |
743 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
744 | struct cgroup_subsys_state *css; | |
745 | ||
746 | if (cgrp) { | |
747 | for (css = &cgrp->css; css; css = css->parent) { | |
748 | cgrp = container_of(css, struct perf_cgroup, css); | |
749 | __update_cgrp_time(cgrp); | |
750 | } | |
751 | } | |
e5d1367f SE |
752 | } |
753 | ||
754 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
755 | { | |
3f7cce3c SE |
756 | struct perf_cgroup *cgrp; |
757 | ||
e5d1367f | 758 | /* |
3f7cce3c SE |
759 | * ensure we access cgroup data only when needed and |
760 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 761 | */ |
3f7cce3c | 762 | if (!is_cgroup_event(event)) |
e5d1367f SE |
763 | return; |
764 | ||
614e4c4e | 765 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
766 | /* |
767 | * Do not update time when cgroup is not active | |
768 | */ | |
28fa741c | 769 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 770 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
771 | } |
772 | ||
773 | static inline void | |
3f7cce3c SE |
774 | perf_cgroup_set_timestamp(struct task_struct *task, |
775 | struct perf_event_context *ctx) | |
e5d1367f SE |
776 | { |
777 | struct perf_cgroup *cgrp; | |
778 | struct perf_cgroup_info *info; | |
c917e0f2 | 779 | struct cgroup_subsys_state *css; |
e5d1367f | 780 | |
3f7cce3c SE |
781 | /* |
782 | * ctx->lock held by caller | |
783 | * ensure we do not access cgroup data | |
784 | * unless we have the cgroup pinned (css_get) | |
785 | */ | |
786 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
787 | return; |
788 | ||
614e4c4e | 789 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
790 | |
791 | for (css = &cgrp->css; css; css = css->parent) { | |
792 | cgrp = container_of(css, struct perf_cgroup, css); | |
793 | info = this_cpu_ptr(cgrp->info); | |
794 | info->timestamp = ctx->timestamp; | |
795 | } | |
e5d1367f SE |
796 | } |
797 | ||
058fe1c0 DCC |
798 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
799 | ||
e5d1367f SE |
800 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
801 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
802 | ||
803 | /* | |
804 | * reschedule events based on the cgroup constraint of task. | |
805 | * | |
806 | * mode SWOUT : schedule out everything | |
807 | * mode SWIN : schedule in based on cgroup for next | |
808 | */ | |
18ab2cd3 | 809 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
810 | { |
811 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 812 | struct list_head *list; |
e5d1367f SE |
813 | unsigned long flags; |
814 | ||
815 | /* | |
058fe1c0 DCC |
816 | * Disable interrupts and preemption to avoid this CPU's |
817 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
818 | */ |
819 | local_irq_save(flags); | |
820 | ||
058fe1c0 DCC |
821 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
822 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
823 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 824 | |
058fe1c0 DCC |
825 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
826 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 827 | |
058fe1c0 DCC |
828 | if (mode & PERF_CGROUP_SWOUT) { |
829 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
830 | /* | |
831 | * must not be done before ctxswout due | |
832 | * to event_filter_match() in event_sched_out() | |
833 | */ | |
834 | cpuctx->cgrp = NULL; | |
835 | } | |
e5d1367f | 836 | |
058fe1c0 DCC |
837 | if (mode & PERF_CGROUP_SWIN) { |
838 | WARN_ON_ONCE(cpuctx->cgrp); | |
839 | /* | |
840 | * set cgrp before ctxsw in to allow | |
841 | * event_filter_match() to not have to pass | |
842 | * task around | |
843 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
844 | * because cgorup events are only per-cpu | |
845 | */ | |
846 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
847 | &cpuctx->ctx); | |
848 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 849 | } |
058fe1c0 DCC |
850 | perf_pmu_enable(cpuctx->ctx.pmu); |
851 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
852 | } |
853 | ||
e5d1367f SE |
854 | local_irq_restore(flags); |
855 | } | |
856 | ||
a8d757ef SE |
857 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
858 | struct task_struct *next) | |
e5d1367f | 859 | { |
a8d757ef SE |
860 | struct perf_cgroup *cgrp1; |
861 | struct perf_cgroup *cgrp2 = NULL; | |
862 | ||
ddaaf4e2 | 863 | rcu_read_lock(); |
a8d757ef SE |
864 | /* |
865 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
866 | * we do not need to pass the ctx here because we know |
867 | * we are holding the rcu lock | |
a8d757ef | 868 | */ |
614e4c4e | 869 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 870 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
871 | |
872 | /* | |
873 | * only schedule out current cgroup events if we know | |
874 | * that we are switching to a different cgroup. Otherwise, | |
875 | * do no touch the cgroup events. | |
876 | */ | |
877 | if (cgrp1 != cgrp2) | |
878 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
879 | |
880 | rcu_read_unlock(); | |
e5d1367f SE |
881 | } |
882 | ||
a8d757ef SE |
883 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
884 | struct task_struct *task) | |
e5d1367f | 885 | { |
a8d757ef SE |
886 | struct perf_cgroup *cgrp1; |
887 | struct perf_cgroup *cgrp2 = NULL; | |
888 | ||
ddaaf4e2 | 889 | rcu_read_lock(); |
a8d757ef SE |
890 | /* |
891 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
892 | * we do not need to pass the ctx here because we know |
893 | * we are holding the rcu lock | |
a8d757ef | 894 | */ |
614e4c4e | 895 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 896 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
897 | |
898 | /* | |
899 | * only need to schedule in cgroup events if we are changing | |
900 | * cgroup during ctxsw. Cgroup events were not scheduled | |
901 | * out of ctxsw out if that was not the case. | |
902 | */ | |
903 | if (cgrp1 != cgrp2) | |
904 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
905 | |
906 | rcu_read_unlock(); | |
e5d1367f SE |
907 | } |
908 | ||
c2283c93 IR |
909 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
910 | struct cgroup_subsys_state *css) | |
911 | { | |
912 | struct perf_cpu_context *cpuctx; | |
913 | struct perf_event **storage; | |
914 | int cpu, heap_size, ret = 0; | |
915 | ||
916 | /* | |
917 | * Allow storage to have sufficent space for an iterator for each | |
918 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
919 | */ | |
920 | for (heap_size = 1; css; css = css->parent) | |
921 | heap_size++; | |
922 | ||
923 | for_each_possible_cpu(cpu) { | |
924 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
925 | if (heap_size <= cpuctx->heap_size) | |
926 | continue; | |
927 | ||
928 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
929 | GFP_KERNEL, cpu_to_node(cpu)); | |
930 | if (!storage) { | |
931 | ret = -ENOMEM; | |
932 | break; | |
933 | } | |
934 | ||
935 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
936 | if (cpuctx->heap_size < heap_size) { | |
937 | swap(cpuctx->heap, storage); | |
938 | if (storage == cpuctx->heap_default) | |
939 | storage = NULL; | |
940 | cpuctx->heap_size = heap_size; | |
941 | } | |
942 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
943 | ||
944 | kfree(storage); | |
945 | } | |
946 | ||
947 | return ret; | |
948 | } | |
949 | ||
e5d1367f SE |
950 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
951 | struct perf_event_attr *attr, | |
952 | struct perf_event *group_leader) | |
953 | { | |
954 | struct perf_cgroup *cgrp; | |
955 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
956 | struct fd f = fdget(fd); |
957 | int ret = 0; | |
e5d1367f | 958 | |
2903ff01 | 959 | if (!f.file) |
e5d1367f SE |
960 | return -EBADF; |
961 | ||
b583043e | 962 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 963 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
964 | if (IS_ERR(css)) { |
965 | ret = PTR_ERR(css); | |
966 | goto out; | |
967 | } | |
e5d1367f | 968 | |
c2283c93 IR |
969 | ret = perf_cgroup_ensure_storage(event, css); |
970 | if (ret) | |
971 | goto out; | |
972 | ||
e5d1367f SE |
973 | cgrp = container_of(css, struct perf_cgroup, css); |
974 | event->cgrp = cgrp; | |
975 | ||
976 | /* | |
977 | * all events in a group must monitor | |
978 | * the same cgroup because a task belongs | |
979 | * to only one perf cgroup at a time | |
980 | */ | |
981 | if (group_leader && group_leader->cgrp != cgrp) { | |
982 | perf_detach_cgroup(event); | |
983 | ret = -EINVAL; | |
e5d1367f | 984 | } |
3db272c0 | 985 | out: |
2903ff01 | 986 | fdput(f); |
e5d1367f SE |
987 | return ret; |
988 | } | |
989 | ||
990 | static inline void | |
991 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
992 | { | |
993 | struct perf_cgroup_info *t; | |
994 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
995 | event->shadow_ctx_time = now - t->timestamp; | |
996 | } | |
997 | ||
db4a8356 | 998 | static inline void |
33238c50 | 999 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1000 | { |
1001 | struct perf_cpu_context *cpuctx; | |
1002 | ||
1003 | if (!is_cgroup_event(event)) | |
1004 | return; | |
1005 | ||
db4a8356 DCC |
1006 | /* |
1007 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1008 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1009 | */ |
07c59729 | 1010 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1011 | |
1012 | /* | |
1013 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1014 | * matching the event's cgroup, we must do this for every new event, | |
1015 | * because if the first would mismatch, the second would not try again | |
1016 | * and we would leave cpuctx->cgrp unset. | |
1017 | */ | |
33238c50 | 1018 | if (ctx->is_active && !cpuctx->cgrp) { |
be96b316 TH |
1019 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1020 | ||
be96b316 TH |
1021 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1022 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1023 | } |
33801b94 | 1024 | |
33238c50 | 1025 | if (ctx->nr_cgroups++) |
33801b94 | 1026 | return; |
33238c50 PZ |
1027 | |
1028 | list_add(&cpuctx->cgrp_cpuctx_entry, | |
1029 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
1030 | } | |
1031 | ||
1032 | static inline void | |
1033 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1034 | { | |
1035 | struct perf_cpu_context *cpuctx; | |
1036 | ||
1037 | if (!is_cgroup_event(event)) | |
33801b94 | 1038 | return; |
1039 | ||
33238c50 PZ |
1040 | /* |
1041 | * Because cgroup events are always per-cpu events, | |
1042 | * @ctx == &cpuctx->ctx. | |
1043 | */ | |
1044 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); | |
1045 | ||
1046 | if (--ctx->nr_cgroups) | |
1047 | return; | |
1048 | ||
1049 | if (ctx->is_active && cpuctx->cgrp) | |
33801b94 | 1050 | cpuctx->cgrp = NULL; |
1051 | ||
33238c50 | 1052 | list_del(&cpuctx->cgrp_cpuctx_entry); |
db4a8356 DCC |
1053 | } |
1054 | ||
e5d1367f SE |
1055 | #else /* !CONFIG_CGROUP_PERF */ |
1056 | ||
1057 | static inline bool | |
1058 | perf_cgroup_match(struct perf_event *event) | |
1059 | { | |
1060 | return true; | |
1061 | } | |
1062 | ||
1063 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1064 | {} | |
1065 | ||
1066 | static inline int is_cgroup_event(struct perf_event *event) | |
1067 | { | |
1068 | return 0; | |
1069 | } | |
1070 | ||
e5d1367f SE |
1071 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1072 | { | |
1073 | } | |
1074 | ||
1075 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1076 | { | |
1077 | } | |
1078 | ||
a8d757ef SE |
1079 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1080 | struct task_struct *next) | |
e5d1367f SE |
1081 | { |
1082 | } | |
1083 | ||
a8d757ef SE |
1084 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1085 | struct task_struct *task) | |
e5d1367f SE |
1086 | { |
1087 | } | |
1088 | ||
1089 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1090 | struct perf_event_attr *attr, | |
1091 | struct perf_event *group_leader) | |
1092 | { | |
1093 | return -EINVAL; | |
1094 | } | |
1095 | ||
1096 | static inline void | |
3f7cce3c SE |
1097 | perf_cgroup_set_timestamp(struct task_struct *task, |
1098 | struct perf_event_context *ctx) | |
e5d1367f SE |
1099 | { |
1100 | } | |
1101 | ||
d00dbd29 | 1102 | static inline void |
e5d1367f SE |
1103 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1104 | { | |
1105 | } | |
1106 | ||
1107 | static inline void | |
1108 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1109 | { | |
1110 | } | |
1111 | ||
1112 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1113 | { | |
1114 | return 0; | |
1115 | } | |
1116 | ||
db4a8356 | 1117 | static inline void |
33238c50 | 1118 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1119 | { |
1120 | } | |
1121 | ||
33238c50 PZ |
1122 | static inline void |
1123 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1124 | { | |
1125 | } | |
e5d1367f SE |
1126 | #endif |
1127 | ||
9e630205 SE |
1128 | /* |
1129 | * set default to be dependent on timer tick just | |
1130 | * like original code | |
1131 | */ | |
1132 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1133 | /* | |
8a1115ff | 1134 | * function must be called with interrupts disabled |
9e630205 | 1135 | */ |
272325c4 | 1136 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1137 | { |
1138 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1139 | bool rotations; |
9e630205 | 1140 | |
16444645 | 1141 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1142 | |
1143 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1144 | rotations = perf_rotate_context(cpuctx); |
1145 | ||
4cfafd30 PZ |
1146 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1147 | if (rotations) | |
9e630205 | 1148 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1149 | else |
1150 | cpuctx->hrtimer_active = 0; | |
1151 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1152 | |
4cfafd30 | 1153 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1154 | } |
1155 | ||
272325c4 | 1156 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1157 | { |
272325c4 | 1158 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1159 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1160 | u64 interval; |
9e630205 SE |
1161 | |
1162 | /* no multiplexing needed for SW PMU */ | |
1163 | if (pmu->task_ctx_nr == perf_sw_context) | |
1164 | return; | |
1165 | ||
62b85639 SE |
1166 | /* |
1167 | * check default is sane, if not set then force to | |
1168 | * default interval (1/tick) | |
1169 | */ | |
272325c4 PZ |
1170 | interval = pmu->hrtimer_interval_ms; |
1171 | if (interval < 1) | |
1172 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1173 | |
272325c4 | 1174 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1175 | |
4cfafd30 | 1176 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1177 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1178 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1179 | } |
1180 | ||
272325c4 | 1181 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1182 | { |
272325c4 | 1183 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1184 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1185 | unsigned long flags; |
9e630205 SE |
1186 | |
1187 | /* not for SW PMU */ | |
1188 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1189 | return 0; |
9e630205 | 1190 | |
4cfafd30 PZ |
1191 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1192 | if (!cpuctx->hrtimer_active) { | |
1193 | cpuctx->hrtimer_active = 1; | |
1194 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1195 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1196 | } |
1197 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1198 | |
272325c4 | 1199 | return 0; |
9e630205 SE |
1200 | } |
1201 | ||
33696fc0 | 1202 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1203 | { |
33696fc0 PZ |
1204 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1205 | if (!(*count)++) | |
1206 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1207 | } |
9e35ad38 | 1208 | |
33696fc0 | 1209 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1210 | { |
33696fc0 PZ |
1211 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1212 | if (!--(*count)) | |
1213 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1214 | } |
9e35ad38 | 1215 | |
2fde4f94 | 1216 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1217 | |
1218 | /* | |
2fde4f94 MR |
1219 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1220 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1221 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1222 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1223 | */ |
2fde4f94 | 1224 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1225 | { |
2fde4f94 | 1226 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1227 | |
16444645 | 1228 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1229 | |
2fde4f94 MR |
1230 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1231 | ||
1232 | list_add(&ctx->active_ctx_list, head); | |
1233 | } | |
1234 | ||
1235 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1236 | { | |
16444645 | 1237 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1238 | |
1239 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1240 | ||
1241 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1242 | } |
9e35ad38 | 1243 | |
cdd6c482 | 1244 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1245 | { |
8c94abbb | 1246 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1247 | } |
1248 | ||
ff9ff926 KL |
1249 | static void *alloc_task_ctx_data(struct pmu *pmu) |
1250 | { | |
217c2a63 KL |
1251 | if (pmu->task_ctx_cache) |
1252 | return kmem_cache_zalloc(pmu->task_ctx_cache, GFP_KERNEL); | |
1253 | ||
5a09928d | 1254 | return NULL; |
ff9ff926 KL |
1255 | } |
1256 | ||
1257 | static void free_task_ctx_data(struct pmu *pmu, void *task_ctx_data) | |
1258 | { | |
217c2a63 KL |
1259 | if (pmu->task_ctx_cache && task_ctx_data) |
1260 | kmem_cache_free(pmu->task_ctx_cache, task_ctx_data); | |
ff9ff926 KL |
1261 | } |
1262 | ||
4af57ef2 YZ |
1263 | static void free_ctx(struct rcu_head *head) |
1264 | { | |
1265 | struct perf_event_context *ctx; | |
1266 | ||
1267 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
ff9ff926 | 1268 | free_task_ctx_data(ctx->pmu, ctx->task_ctx_data); |
4af57ef2 YZ |
1269 | kfree(ctx); |
1270 | } | |
1271 | ||
cdd6c482 | 1272 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1273 | { |
8c94abbb | 1274 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1275 | if (ctx->parent_ctx) |
1276 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1277 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1278 | put_task_struct(ctx->task); |
4af57ef2 | 1279 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1280 | } |
a63eaf34 PM |
1281 | } |
1282 | ||
f63a8daa PZ |
1283 | /* |
1284 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1285 | * perf_pmu_migrate_context() we need some magic. | |
1286 | * | |
1287 | * Those places that change perf_event::ctx will hold both | |
1288 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1289 | * | |
8b10c5e2 PZ |
1290 | * Lock ordering is by mutex address. There are two other sites where |
1291 | * perf_event_context::mutex nests and those are: | |
1292 | * | |
1293 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1294 | * perf_event_exit_event() |
1295 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1296 | * |
1297 | * - perf_event_init_context() [ parent, 0 ] | |
1298 | * inherit_task_group() | |
1299 | * inherit_group() | |
1300 | * inherit_event() | |
1301 | * perf_event_alloc() | |
1302 | * perf_init_event() | |
1303 | * perf_try_init_event() [ child , 1 ] | |
1304 | * | |
1305 | * While it appears there is an obvious deadlock here -- the parent and child | |
1306 | * nesting levels are inverted between the two. This is in fact safe because | |
1307 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1308 | * spawning task cannot (yet) exit. | |
1309 | * | |
1310 | * But remember that that these are parent<->child context relations, and | |
1311 | * migration does not affect children, therefore these two orderings should not | |
1312 | * interact. | |
f63a8daa PZ |
1313 | * |
1314 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1315 | * because the sys_perf_event_open() case will install a new event and break | |
1316 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1317 | * concerned with cpuctx and that doesn't have children. | |
1318 | * | |
1319 | * The places that change perf_event::ctx will issue: | |
1320 | * | |
1321 | * perf_remove_from_context(); | |
1322 | * synchronize_rcu(); | |
1323 | * perf_install_in_context(); | |
1324 | * | |
1325 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1326 | * quiesce the event, after which we can install it in the new location. This | |
1327 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1328 | * while in transit. Therefore all such accessors should also acquire | |
1329 | * perf_event_context::mutex to serialize against this. | |
1330 | * | |
1331 | * However; because event->ctx can change while we're waiting to acquire | |
1332 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1333 | * function. | |
1334 | * | |
1335 | * Lock order: | |
f7cfd871 | 1336 | * exec_update_lock |
f63a8daa PZ |
1337 | * task_struct::perf_event_mutex |
1338 | * perf_event_context::mutex | |
f63a8daa | 1339 | * perf_event::child_mutex; |
07c4a776 | 1340 | * perf_event_context::lock |
f63a8daa | 1341 | * perf_event::mmap_mutex |
c1e8d7c6 | 1342 | * mmap_lock |
18736eef | 1343 | * perf_addr_filters_head::lock |
82d94856 PZ |
1344 | * |
1345 | * cpu_hotplug_lock | |
1346 | * pmus_lock | |
1347 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1348 | */ |
a83fe28e PZ |
1349 | static struct perf_event_context * |
1350 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1351 | { |
1352 | struct perf_event_context *ctx; | |
1353 | ||
1354 | again: | |
1355 | rcu_read_lock(); | |
6aa7de05 | 1356 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1357 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1358 | rcu_read_unlock(); |
1359 | goto again; | |
1360 | } | |
1361 | rcu_read_unlock(); | |
1362 | ||
a83fe28e | 1363 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1364 | if (event->ctx != ctx) { |
1365 | mutex_unlock(&ctx->mutex); | |
1366 | put_ctx(ctx); | |
1367 | goto again; | |
1368 | } | |
1369 | ||
1370 | return ctx; | |
1371 | } | |
1372 | ||
a83fe28e PZ |
1373 | static inline struct perf_event_context * |
1374 | perf_event_ctx_lock(struct perf_event *event) | |
1375 | { | |
1376 | return perf_event_ctx_lock_nested(event, 0); | |
1377 | } | |
1378 | ||
f63a8daa PZ |
1379 | static void perf_event_ctx_unlock(struct perf_event *event, |
1380 | struct perf_event_context *ctx) | |
1381 | { | |
1382 | mutex_unlock(&ctx->mutex); | |
1383 | put_ctx(ctx); | |
1384 | } | |
1385 | ||
211de6eb PZ |
1386 | /* |
1387 | * This must be done under the ctx->lock, such as to serialize against | |
1388 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1389 | * calling scheduler related locks and ctx->lock nests inside those. | |
1390 | */ | |
1391 | static __must_check struct perf_event_context * | |
1392 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1393 | { |
211de6eb PZ |
1394 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1395 | ||
1396 | lockdep_assert_held(&ctx->lock); | |
1397 | ||
1398 | if (parent_ctx) | |
71a851b4 | 1399 | ctx->parent_ctx = NULL; |
5a3126d4 | 1400 | ctx->generation++; |
211de6eb PZ |
1401 | |
1402 | return parent_ctx; | |
71a851b4 PZ |
1403 | } |
1404 | ||
1d953111 ON |
1405 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1406 | enum pid_type type) | |
6844c09d | 1407 | { |
1d953111 | 1408 | u32 nr; |
6844c09d ACM |
1409 | /* |
1410 | * only top level events have the pid namespace they were created in | |
1411 | */ | |
1412 | if (event->parent) | |
1413 | event = event->parent; | |
1414 | ||
1d953111 ON |
1415 | nr = __task_pid_nr_ns(p, type, event->ns); |
1416 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1417 | if (!nr && !pid_alive(p)) | |
1418 | nr = -1; | |
1419 | return nr; | |
6844c09d ACM |
1420 | } |
1421 | ||
1d953111 | 1422 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1423 | { |
6883f81a | 1424 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1425 | } |
6844c09d | 1426 | |
1d953111 ON |
1427 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1428 | { | |
1429 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1430 | } |
1431 | ||
7f453c24 | 1432 | /* |
cdd6c482 | 1433 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1434 | * to userspace. |
1435 | */ | |
cdd6c482 | 1436 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1437 | { |
cdd6c482 | 1438 | u64 id = event->id; |
7f453c24 | 1439 | |
cdd6c482 IM |
1440 | if (event->parent) |
1441 | id = event->parent->id; | |
7f453c24 PZ |
1442 | |
1443 | return id; | |
1444 | } | |
1445 | ||
25346b93 | 1446 | /* |
cdd6c482 | 1447 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1448 | * |
25346b93 PM |
1449 | * This has to cope with with the fact that until it is locked, |
1450 | * the context could get moved to another task. | |
1451 | */ | |
cdd6c482 | 1452 | static struct perf_event_context * |
8dc85d54 | 1453 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1454 | { |
cdd6c482 | 1455 | struct perf_event_context *ctx; |
25346b93 | 1456 | |
9ed6060d | 1457 | retry: |
058ebd0e PZ |
1458 | /* |
1459 | * One of the few rules of preemptible RCU is that one cannot do | |
1460 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1461 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1462 | * rcu_read_unlock_special(). |
1463 | * | |
1464 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1465 | * side critical section has interrupts disabled. |
058ebd0e | 1466 | */ |
2fd59077 | 1467 | local_irq_save(*flags); |
058ebd0e | 1468 | rcu_read_lock(); |
8dc85d54 | 1469 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1470 | if (ctx) { |
1471 | /* | |
1472 | * If this context is a clone of another, it might | |
1473 | * get swapped for another underneath us by | |
cdd6c482 | 1474 | * perf_event_task_sched_out, though the |
25346b93 PM |
1475 | * rcu_read_lock() protects us from any context |
1476 | * getting freed. Lock the context and check if it | |
1477 | * got swapped before we could get the lock, and retry | |
1478 | * if so. If we locked the right context, then it | |
1479 | * can't get swapped on us any more. | |
1480 | */ | |
2fd59077 | 1481 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1482 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1483 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1484 | rcu_read_unlock(); |
2fd59077 | 1485 | local_irq_restore(*flags); |
25346b93 PM |
1486 | goto retry; |
1487 | } | |
b49a9e7e | 1488 | |
63b6da39 | 1489 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1490 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1491 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1492 | ctx = NULL; |
828b6f0e PZ |
1493 | } else { |
1494 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1495 | } |
25346b93 PM |
1496 | } |
1497 | rcu_read_unlock(); | |
2fd59077 PM |
1498 | if (!ctx) |
1499 | local_irq_restore(*flags); | |
25346b93 PM |
1500 | return ctx; |
1501 | } | |
1502 | ||
1503 | /* | |
1504 | * Get the context for a task and increment its pin_count so it | |
1505 | * can't get swapped to another task. This also increments its | |
1506 | * reference count so that the context can't get freed. | |
1507 | */ | |
8dc85d54 PZ |
1508 | static struct perf_event_context * |
1509 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1510 | { |
cdd6c482 | 1511 | struct perf_event_context *ctx; |
25346b93 PM |
1512 | unsigned long flags; |
1513 | ||
8dc85d54 | 1514 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1515 | if (ctx) { |
1516 | ++ctx->pin_count; | |
e625cce1 | 1517 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1518 | } |
1519 | return ctx; | |
1520 | } | |
1521 | ||
cdd6c482 | 1522 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1523 | { |
1524 | unsigned long flags; | |
1525 | ||
e625cce1 | 1526 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1527 | --ctx->pin_count; |
e625cce1 | 1528 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1529 | } |
1530 | ||
f67218c3 PZ |
1531 | /* |
1532 | * Update the record of the current time in a context. | |
1533 | */ | |
1534 | static void update_context_time(struct perf_event_context *ctx) | |
1535 | { | |
1536 | u64 now = perf_clock(); | |
1537 | ||
1538 | ctx->time += now - ctx->timestamp; | |
1539 | ctx->timestamp = now; | |
1540 | } | |
1541 | ||
4158755d SE |
1542 | static u64 perf_event_time(struct perf_event *event) |
1543 | { | |
1544 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1545 | |
1546 | if (is_cgroup_event(event)) | |
1547 | return perf_cgroup_event_time(event); | |
1548 | ||
4158755d SE |
1549 | return ctx ? ctx->time : 0; |
1550 | } | |
1551 | ||
487f05e1 AS |
1552 | static enum event_type_t get_event_type(struct perf_event *event) |
1553 | { | |
1554 | struct perf_event_context *ctx = event->ctx; | |
1555 | enum event_type_t event_type; | |
1556 | ||
1557 | lockdep_assert_held(&ctx->lock); | |
1558 | ||
3bda69c1 AS |
1559 | /* |
1560 | * It's 'group type', really, because if our group leader is | |
1561 | * pinned, so are we. | |
1562 | */ | |
1563 | if (event->group_leader != event) | |
1564 | event = event->group_leader; | |
1565 | ||
487f05e1 AS |
1566 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1567 | if (!ctx->task) | |
1568 | event_type |= EVENT_CPU; | |
1569 | ||
1570 | return event_type; | |
1571 | } | |
1572 | ||
8e1a2031 | 1573 | /* |
161c85fa | 1574 | * Helper function to initialize event group nodes. |
8e1a2031 | 1575 | */ |
161c85fa | 1576 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1577 | { |
1578 | RB_CLEAR_NODE(&event->group_node); | |
1579 | event->group_index = 0; | |
1580 | } | |
1581 | ||
1582 | /* | |
1583 | * Extract pinned or flexible groups from the context | |
161c85fa | 1584 | * based on event attrs bits. |
8e1a2031 AB |
1585 | */ |
1586 | static struct perf_event_groups * | |
1587 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1588 | { |
1589 | if (event->attr.pinned) | |
1590 | return &ctx->pinned_groups; | |
1591 | else | |
1592 | return &ctx->flexible_groups; | |
1593 | } | |
1594 | ||
8e1a2031 | 1595 | /* |
161c85fa | 1596 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1597 | */ |
161c85fa | 1598 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1599 | { |
1600 | groups->tree = RB_ROOT; | |
1601 | groups->index = 0; | |
1602 | } | |
1603 | ||
1604 | /* | |
1605 | * Compare function for event groups; | |
161c85fa PZ |
1606 | * |
1607 | * Implements complex key that first sorts by CPU and then by virtual index | |
1608 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1609 | */ |
161c85fa PZ |
1610 | static bool |
1611 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1612 | { |
161c85fa PZ |
1613 | if (left->cpu < right->cpu) |
1614 | return true; | |
1615 | if (left->cpu > right->cpu) | |
1616 | return false; | |
1617 | ||
95ed6c70 IR |
1618 | #ifdef CONFIG_CGROUP_PERF |
1619 | if (left->cgrp != right->cgrp) { | |
1620 | if (!left->cgrp || !left->cgrp->css.cgroup) { | |
1621 | /* | |
1622 | * Left has no cgroup but right does, no cgroups come | |
1623 | * first. | |
1624 | */ | |
1625 | return true; | |
1626 | } | |
a6763625 | 1627 | if (!right->cgrp || !right->cgrp->css.cgroup) { |
95ed6c70 IR |
1628 | /* |
1629 | * Right has no cgroup but left does, no cgroups come | |
1630 | * first. | |
1631 | */ | |
1632 | return false; | |
1633 | } | |
1634 | /* Two dissimilar cgroups, order by id. */ | |
1635 | if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) | |
1636 | return true; | |
1637 | ||
1638 | return false; | |
1639 | } | |
1640 | #endif | |
1641 | ||
161c85fa PZ |
1642 | if (left->group_index < right->group_index) |
1643 | return true; | |
1644 | if (left->group_index > right->group_index) | |
1645 | return false; | |
1646 | ||
1647 | return false; | |
8e1a2031 AB |
1648 | } |
1649 | ||
1650 | /* | |
161c85fa PZ |
1651 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1652 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1653 | * subtree. | |
8e1a2031 AB |
1654 | */ |
1655 | static void | |
1656 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1657 | struct perf_event *event) |
8e1a2031 AB |
1658 | { |
1659 | struct perf_event *node_event; | |
1660 | struct rb_node *parent; | |
1661 | struct rb_node **node; | |
1662 | ||
1663 | event->group_index = ++groups->index; | |
1664 | ||
1665 | node = &groups->tree.rb_node; | |
1666 | parent = *node; | |
1667 | ||
1668 | while (*node) { | |
1669 | parent = *node; | |
161c85fa | 1670 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1671 | |
1672 | if (perf_event_groups_less(event, node_event)) | |
1673 | node = &parent->rb_left; | |
1674 | else | |
1675 | node = &parent->rb_right; | |
1676 | } | |
1677 | ||
1678 | rb_link_node(&event->group_node, parent, node); | |
1679 | rb_insert_color(&event->group_node, &groups->tree); | |
1680 | } | |
1681 | ||
1682 | /* | |
161c85fa | 1683 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1684 | */ |
1685 | static void | |
1686 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1687 | { | |
1688 | struct perf_event_groups *groups; | |
1689 | ||
1690 | groups = get_event_groups(event, ctx); | |
1691 | perf_event_groups_insert(groups, event); | |
1692 | } | |
1693 | ||
1694 | /* | |
161c85fa | 1695 | * Delete a group from a tree. |
8e1a2031 AB |
1696 | */ |
1697 | static void | |
1698 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1699 | struct perf_event *event) |
8e1a2031 | 1700 | { |
161c85fa PZ |
1701 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1702 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1703 | |
161c85fa | 1704 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1705 | init_event_group(event); |
1706 | } | |
1707 | ||
1708 | /* | |
161c85fa | 1709 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1710 | */ |
1711 | static void | |
1712 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1713 | { | |
1714 | struct perf_event_groups *groups; | |
1715 | ||
1716 | groups = get_event_groups(event, ctx); | |
1717 | perf_event_groups_delete(groups, event); | |
1718 | } | |
1719 | ||
1720 | /* | |
95ed6c70 | 1721 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1722 | */ |
1723 | static struct perf_event * | |
95ed6c70 IR |
1724 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1725 | struct cgroup *cgrp) | |
8e1a2031 AB |
1726 | { |
1727 | struct perf_event *node_event = NULL, *match = NULL; | |
1728 | struct rb_node *node = groups->tree.rb_node; | |
95ed6c70 IR |
1729 | #ifdef CONFIG_CGROUP_PERF |
1730 | u64 node_cgrp_id, cgrp_id = 0; | |
1731 | ||
1732 | if (cgrp) | |
1733 | cgrp_id = cgrp->kn->id; | |
1734 | #endif | |
8e1a2031 AB |
1735 | |
1736 | while (node) { | |
161c85fa | 1737 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1738 | |
1739 | if (cpu < node_event->cpu) { | |
1740 | node = node->rb_left; | |
95ed6c70 IR |
1741 | continue; |
1742 | } | |
1743 | if (cpu > node_event->cpu) { | |
8e1a2031 | 1744 | node = node->rb_right; |
95ed6c70 IR |
1745 | continue; |
1746 | } | |
1747 | #ifdef CONFIG_CGROUP_PERF | |
1748 | node_cgrp_id = 0; | |
1749 | if (node_event->cgrp && node_event->cgrp->css.cgroup) | |
1750 | node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; | |
1751 | ||
1752 | if (cgrp_id < node_cgrp_id) { | |
8e1a2031 | 1753 | node = node->rb_left; |
95ed6c70 IR |
1754 | continue; |
1755 | } | |
1756 | if (cgrp_id > node_cgrp_id) { | |
1757 | node = node->rb_right; | |
1758 | continue; | |
8e1a2031 | 1759 | } |
95ed6c70 IR |
1760 | #endif |
1761 | match = node_event; | |
1762 | node = node->rb_left; | |
8e1a2031 AB |
1763 | } |
1764 | ||
1765 | return match; | |
1766 | } | |
1767 | ||
1cac7b1a PZ |
1768 | /* |
1769 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1770 | */ | |
1771 | static struct perf_event * | |
1772 | perf_event_groups_next(struct perf_event *event) | |
1773 | { | |
1774 | struct perf_event *next; | |
95ed6c70 IR |
1775 | #ifdef CONFIG_CGROUP_PERF |
1776 | u64 curr_cgrp_id = 0; | |
1777 | u64 next_cgrp_id = 0; | |
1778 | #endif | |
1cac7b1a PZ |
1779 | |
1780 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
95ed6c70 IR |
1781 | if (next == NULL || next->cpu != event->cpu) |
1782 | return NULL; | |
1783 | ||
1784 | #ifdef CONFIG_CGROUP_PERF | |
1785 | if (event->cgrp && event->cgrp->css.cgroup) | |
1786 | curr_cgrp_id = event->cgrp->css.cgroup->kn->id; | |
1cac7b1a | 1787 | |
95ed6c70 IR |
1788 | if (next->cgrp && next->cgrp->css.cgroup) |
1789 | next_cgrp_id = next->cgrp->css.cgroup->kn->id; | |
1790 | ||
1791 | if (curr_cgrp_id != next_cgrp_id) | |
1792 | return NULL; | |
1793 | #endif | |
1794 | return next; | |
1cac7b1a PZ |
1795 | } |
1796 | ||
8e1a2031 | 1797 | /* |
161c85fa | 1798 | * Iterate through the whole groups tree. |
8e1a2031 | 1799 | */ |
6e6804d2 PZ |
1800 | #define perf_event_groups_for_each(event, groups) \ |
1801 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1802 | typeof(*event), group_node); event; \ | |
1803 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1804 | typeof(*event), group_node)) | |
8e1a2031 | 1805 | |
fccc714b | 1806 | /* |
788faab7 | 1807 | * Add an event from the lists for its context. |
fccc714b PZ |
1808 | * Must be called with ctx->mutex and ctx->lock held. |
1809 | */ | |
04289bb9 | 1810 | static void |
cdd6c482 | 1811 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1812 | { |
c994d613 PZ |
1813 | lockdep_assert_held(&ctx->lock); |
1814 | ||
8a49542c PZ |
1815 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1816 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1817 | |
0d3d73aa PZ |
1818 | event->tstamp = perf_event_time(event); |
1819 | ||
04289bb9 | 1820 | /* |
8a49542c PZ |
1821 | * If we're a stand alone event or group leader, we go to the context |
1822 | * list, group events are kept attached to the group so that | |
1823 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1824 | */ |
8a49542c | 1825 | if (event->group_leader == event) { |
4ff6a8de | 1826 | event->group_caps = event->event_caps; |
8e1a2031 | 1827 | add_event_to_groups(event, ctx); |
5c148194 | 1828 | } |
592903cd | 1829 | |
cdd6c482 IM |
1830 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1831 | ctx->nr_events++; | |
1832 | if (event->attr.inherit_stat) | |
bfbd3381 | 1833 | ctx->nr_stat++; |
5a3126d4 | 1834 | |
33238c50 PZ |
1835 | if (event->state > PERF_EVENT_STATE_OFF) |
1836 | perf_cgroup_event_enable(event, ctx); | |
1837 | ||
5a3126d4 | 1838 | ctx->generation++; |
04289bb9 IM |
1839 | } |
1840 | ||
0231bb53 JO |
1841 | /* |
1842 | * Initialize event state based on the perf_event_attr::disabled. | |
1843 | */ | |
1844 | static inline void perf_event__state_init(struct perf_event *event) | |
1845 | { | |
1846 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1847 | PERF_EVENT_STATE_INACTIVE; | |
1848 | } | |
1849 | ||
a723968c | 1850 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1851 | { |
1852 | int entry = sizeof(u64); /* value */ | |
1853 | int size = 0; | |
1854 | int nr = 1; | |
1855 | ||
1856 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1857 | size += sizeof(u64); | |
1858 | ||
1859 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1860 | size += sizeof(u64); | |
1861 | ||
1862 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1863 | entry += sizeof(u64); | |
1864 | ||
1865 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1866 | nr += nr_siblings; |
c320c7b7 ACM |
1867 | size += sizeof(u64); |
1868 | } | |
1869 | ||
1870 | size += entry * nr; | |
1871 | event->read_size = size; | |
1872 | } | |
1873 | ||
a723968c | 1874 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1875 | { |
1876 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1877 | u16 size = 0; |
1878 | ||
c320c7b7 ACM |
1879 | if (sample_type & PERF_SAMPLE_IP) |
1880 | size += sizeof(data->ip); | |
1881 | ||
6844c09d ACM |
1882 | if (sample_type & PERF_SAMPLE_ADDR) |
1883 | size += sizeof(data->addr); | |
1884 | ||
1885 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1886 | size += sizeof(data->period); | |
1887 | ||
c3feedf2 AK |
1888 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1889 | size += sizeof(data->weight); | |
1890 | ||
6844c09d ACM |
1891 | if (sample_type & PERF_SAMPLE_READ) |
1892 | size += event->read_size; | |
1893 | ||
d6be9ad6 SE |
1894 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1895 | size += sizeof(data->data_src.val); | |
1896 | ||
fdfbbd07 AK |
1897 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1898 | size += sizeof(data->txn); | |
1899 | ||
fc7ce9c7 KL |
1900 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1901 | size += sizeof(data->phys_addr); | |
1902 | ||
6546b19f NK |
1903 | if (sample_type & PERF_SAMPLE_CGROUP) |
1904 | size += sizeof(data->cgroup); | |
1905 | ||
8d97e718 KL |
1906 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
1907 | size += sizeof(data->data_page_size); | |
1908 | ||
995f088e SE |
1909 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
1910 | size += sizeof(data->code_page_size); | |
1911 | ||
6844c09d ACM |
1912 | event->header_size = size; |
1913 | } | |
1914 | ||
a723968c PZ |
1915 | /* |
1916 | * Called at perf_event creation and when events are attached/detached from a | |
1917 | * group. | |
1918 | */ | |
1919 | static void perf_event__header_size(struct perf_event *event) | |
1920 | { | |
1921 | __perf_event_read_size(event, | |
1922 | event->group_leader->nr_siblings); | |
1923 | __perf_event_header_size(event, event->attr.sample_type); | |
1924 | } | |
1925 | ||
6844c09d ACM |
1926 | static void perf_event__id_header_size(struct perf_event *event) |
1927 | { | |
1928 | struct perf_sample_data *data; | |
1929 | u64 sample_type = event->attr.sample_type; | |
1930 | u16 size = 0; | |
1931 | ||
c320c7b7 ACM |
1932 | if (sample_type & PERF_SAMPLE_TID) |
1933 | size += sizeof(data->tid_entry); | |
1934 | ||
1935 | if (sample_type & PERF_SAMPLE_TIME) | |
1936 | size += sizeof(data->time); | |
1937 | ||
ff3d527c AH |
1938 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1939 | size += sizeof(data->id); | |
1940 | ||
c320c7b7 ACM |
1941 | if (sample_type & PERF_SAMPLE_ID) |
1942 | size += sizeof(data->id); | |
1943 | ||
1944 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1945 | size += sizeof(data->stream_id); | |
1946 | ||
1947 | if (sample_type & PERF_SAMPLE_CPU) | |
1948 | size += sizeof(data->cpu_entry); | |
1949 | ||
6844c09d | 1950 | event->id_header_size = size; |
c320c7b7 ACM |
1951 | } |
1952 | ||
a723968c PZ |
1953 | static bool perf_event_validate_size(struct perf_event *event) |
1954 | { | |
1955 | /* | |
1956 | * The values computed here will be over-written when we actually | |
1957 | * attach the event. | |
1958 | */ | |
1959 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1960 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1961 | perf_event__id_header_size(event); | |
1962 | ||
1963 | /* | |
1964 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1965 | * Conservative limit to allow for callchains and other variable fields. | |
1966 | */ | |
1967 | if (event->read_size + event->header_size + | |
1968 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1969 | return false; | |
1970 | ||
1971 | return true; | |
1972 | } | |
1973 | ||
8a49542c PZ |
1974 | static void perf_group_attach(struct perf_event *event) |
1975 | { | |
c320c7b7 | 1976 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1977 | |
a76a82a3 PZ |
1978 | lockdep_assert_held(&event->ctx->lock); |
1979 | ||
74c3337c PZ |
1980 | /* |
1981 | * We can have double attach due to group movement in perf_event_open. | |
1982 | */ | |
1983 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1984 | return; | |
1985 | ||
8a49542c PZ |
1986 | event->attach_state |= PERF_ATTACH_GROUP; |
1987 | ||
1988 | if (group_leader == event) | |
1989 | return; | |
1990 | ||
652884fe PZ |
1991 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1992 | ||
4ff6a8de | 1993 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1994 | |
8343aae6 | 1995 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1996 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1997 | |
1998 | perf_event__header_size(group_leader); | |
1999 | ||
edb39592 | 2000 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 2001 | perf_event__header_size(pos); |
8a49542c PZ |
2002 | } |
2003 | ||
a63eaf34 | 2004 | /* |
788faab7 | 2005 | * Remove an event from the lists for its context. |
fccc714b | 2006 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 2007 | */ |
04289bb9 | 2008 | static void |
cdd6c482 | 2009 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 2010 | { |
652884fe PZ |
2011 | WARN_ON_ONCE(event->ctx != ctx); |
2012 | lockdep_assert_held(&ctx->lock); | |
2013 | ||
8a49542c PZ |
2014 | /* |
2015 | * We can have double detach due to exit/hot-unplug + close. | |
2016 | */ | |
2017 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 2018 | return; |
8a49542c PZ |
2019 | |
2020 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
2021 | ||
cdd6c482 IM |
2022 | ctx->nr_events--; |
2023 | if (event->attr.inherit_stat) | |
bfbd3381 | 2024 | ctx->nr_stat--; |
8bc20959 | 2025 | |
cdd6c482 | 2026 | list_del_rcu(&event->event_entry); |
04289bb9 | 2027 | |
8a49542c | 2028 | if (event->group_leader == event) |
8e1a2031 | 2029 | del_event_from_groups(event, ctx); |
5c148194 | 2030 | |
b2e74a26 SE |
2031 | /* |
2032 | * If event was in error state, then keep it | |
2033 | * that way, otherwise bogus counts will be | |
2034 | * returned on read(). The only way to get out | |
2035 | * of error state is by explicit re-enabling | |
2036 | * of the event | |
2037 | */ | |
33238c50 PZ |
2038 | if (event->state > PERF_EVENT_STATE_OFF) { |
2039 | perf_cgroup_event_disable(event, ctx); | |
0d3d73aa | 2040 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
33238c50 | 2041 | } |
5a3126d4 PZ |
2042 | |
2043 | ctx->generation++; | |
050735b0 PZ |
2044 | } |
2045 | ||
ab43762e AS |
2046 | static int |
2047 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2048 | { | |
2049 | if (!has_aux(aux_event)) | |
2050 | return 0; | |
2051 | ||
2052 | if (!event->pmu->aux_output_match) | |
2053 | return 0; | |
2054 | ||
2055 | return event->pmu->aux_output_match(aux_event); | |
2056 | } | |
2057 | ||
2058 | static void put_event(struct perf_event *event); | |
2059 | static void event_sched_out(struct perf_event *event, | |
2060 | struct perf_cpu_context *cpuctx, | |
2061 | struct perf_event_context *ctx); | |
2062 | ||
2063 | static void perf_put_aux_event(struct perf_event *event) | |
2064 | { | |
2065 | struct perf_event_context *ctx = event->ctx; | |
2066 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2067 | struct perf_event *iter; | |
2068 | ||
2069 | /* | |
2070 | * If event uses aux_event tear down the link | |
2071 | */ | |
2072 | if (event->aux_event) { | |
2073 | iter = event->aux_event; | |
2074 | event->aux_event = NULL; | |
2075 | put_event(iter); | |
2076 | return; | |
2077 | } | |
2078 | ||
2079 | /* | |
2080 | * If the event is an aux_event, tear down all links to | |
2081 | * it from other events. | |
2082 | */ | |
2083 | for_each_sibling_event(iter, event->group_leader) { | |
2084 | if (iter->aux_event != event) | |
2085 | continue; | |
2086 | ||
2087 | iter->aux_event = NULL; | |
2088 | put_event(event); | |
2089 | ||
2090 | /* | |
2091 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2092 | * state so that we don't try to schedule it again. Note | |
2093 | * that perf_event_enable() will clear the ERROR status. | |
2094 | */ | |
2095 | event_sched_out(iter, cpuctx, ctx); | |
2096 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2097 | } | |
2098 | } | |
2099 | ||
a4faf00d AS |
2100 | static bool perf_need_aux_event(struct perf_event *event) |
2101 | { | |
2102 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2103 | } | |
2104 | ||
ab43762e AS |
2105 | static int perf_get_aux_event(struct perf_event *event, |
2106 | struct perf_event *group_leader) | |
2107 | { | |
2108 | /* | |
2109 | * Our group leader must be an aux event if we want to be | |
2110 | * an aux_output. This way, the aux event will precede its | |
2111 | * aux_output events in the group, and therefore will always | |
2112 | * schedule first. | |
2113 | */ | |
2114 | if (!group_leader) | |
2115 | return 0; | |
2116 | ||
a4faf00d AS |
2117 | /* |
2118 | * aux_output and aux_sample_size are mutually exclusive. | |
2119 | */ | |
2120 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2121 | return 0; | |
2122 | ||
2123 | if (event->attr.aux_output && | |
2124 | !perf_aux_output_match(event, group_leader)) | |
2125 | return 0; | |
2126 | ||
2127 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2128 | return 0; |
2129 | ||
2130 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2131 | return 0; | |
2132 | ||
2133 | /* | |
2134 | * Link aux_outputs to their aux event; this is undone in | |
2135 | * perf_group_detach() by perf_put_aux_event(). When the | |
2136 | * group in torn down, the aux_output events loose their | |
2137 | * link to the aux_event and can't schedule any more. | |
2138 | */ | |
2139 | event->aux_event = group_leader; | |
2140 | ||
2141 | return 1; | |
2142 | } | |
2143 | ||
ab6f824c PZ |
2144 | static inline struct list_head *get_event_list(struct perf_event *event) |
2145 | { | |
2146 | struct perf_event_context *ctx = event->ctx; | |
2147 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2148 | } | |
2149 | ||
9f0c4fa1 KL |
2150 | /* |
2151 | * Events that have PERF_EV_CAP_SIBLING require being part of a group and | |
2152 | * cannot exist on their own, schedule them out and move them into the ERROR | |
2153 | * state. Also see _perf_event_enable(), it will not be able to recover | |
2154 | * this ERROR state. | |
2155 | */ | |
2156 | static inline void perf_remove_sibling_event(struct perf_event *event) | |
2157 | { | |
2158 | struct perf_event_context *ctx = event->ctx; | |
2159 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2160 | ||
2161 | event_sched_out(event, cpuctx, ctx); | |
2162 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2163 | } | |
2164 | ||
8a49542c | 2165 | static void perf_group_detach(struct perf_event *event) |
050735b0 | 2166 | { |
9f0c4fa1 | 2167 | struct perf_event *leader = event->group_leader; |
050735b0 | 2168 | struct perf_event *sibling, *tmp; |
6668128a | 2169 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2170 | |
6668128a | 2171 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2172 | |
8a49542c PZ |
2173 | /* |
2174 | * We can have double detach due to exit/hot-unplug + close. | |
2175 | */ | |
2176 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2177 | return; | |
2178 | ||
2179 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2180 | ||
ab43762e AS |
2181 | perf_put_aux_event(event); |
2182 | ||
8a49542c PZ |
2183 | /* |
2184 | * If this is a sibling, remove it from its group. | |
2185 | */ | |
9f0c4fa1 | 2186 | if (leader != event) { |
8343aae6 | 2187 | list_del_init(&event->sibling_list); |
8a49542c | 2188 | event->group_leader->nr_siblings--; |
c320c7b7 | 2189 | goto out; |
8a49542c PZ |
2190 | } |
2191 | ||
04289bb9 | 2192 | /* |
cdd6c482 IM |
2193 | * If this was a group event with sibling events then |
2194 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2195 | * to whatever list we are on. |
04289bb9 | 2196 | */ |
8343aae6 | 2197 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2198 | |
9f0c4fa1 KL |
2199 | if (sibling->event_caps & PERF_EV_CAP_SIBLING) |
2200 | perf_remove_sibling_event(sibling); | |
2201 | ||
04289bb9 | 2202 | sibling->group_leader = sibling; |
24868367 | 2203 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2204 | |
2205 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2206 | sibling->group_caps = event->group_caps; |
652884fe | 2207 | |
8e1a2031 | 2208 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2209 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2210 | |
ab6f824c PZ |
2211 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2212 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2213 | } |
2214 | ||
652884fe | 2215 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2216 | } |
c320c7b7 ACM |
2217 | |
2218 | out: | |
9f0c4fa1 | 2219 | for_each_sibling_event(tmp, leader) |
c320c7b7 | 2220 | perf_event__header_size(tmp); |
9f0c4fa1 KL |
2221 | |
2222 | perf_event__header_size(leader); | |
04289bb9 IM |
2223 | } |
2224 | ||
fadfe7be JO |
2225 | static bool is_orphaned_event(struct perf_event *event) |
2226 | { | |
a69b0ca4 | 2227 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2228 | } |
2229 | ||
2c81a647 | 2230 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2231 | { |
2232 | struct pmu *pmu = event->pmu; | |
2233 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2234 | } | |
2235 | ||
2c81a647 MR |
2236 | /* |
2237 | * Check whether we should attempt to schedule an event group based on | |
2238 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2239 | * potentially with a SW leader, so we must check all the filters, to | |
2240 | * determine whether a group is schedulable: | |
2241 | */ | |
2242 | static inline int pmu_filter_match(struct perf_event *event) | |
2243 | { | |
edb39592 | 2244 | struct perf_event *sibling; |
2c81a647 MR |
2245 | |
2246 | if (!__pmu_filter_match(event)) | |
2247 | return 0; | |
2248 | ||
edb39592 PZ |
2249 | for_each_sibling_event(sibling, event) { |
2250 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2251 | return 0; |
2252 | } | |
2253 | ||
2254 | return 1; | |
2255 | } | |
2256 | ||
fa66f07a SE |
2257 | static inline int |
2258 | event_filter_match(struct perf_event *event) | |
2259 | { | |
0b8f1e2e PZ |
2260 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2261 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2262 | } |
2263 | ||
9ffcfa6f SE |
2264 | static void |
2265 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2266 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2267 | struct perf_event_context *ctx) |
3b6f9e5c | 2268 | { |
0d3d73aa | 2269 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2270 | |
2271 | WARN_ON_ONCE(event->ctx != ctx); | |
2272 | lockdep_assert_held(&ctx->lock); | |
2273 | ||
cdd6c482 | 2274 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2275 | return; |
3b6f9e5c | 2276 | |
6668128a PZ |
2277 | /* |
2278 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2279 | * we can schedule events _OUT_ individually through things like | |
2280 | * __perf_remove_from_context(). | |
2281 | */ | |
2282 | list_del_init(&event->active_list); | |
2283 | ||
44377277 AS |
2284 | perf_pmu_disable(event->pmu); |
2285 | ||
28a967c3 PZ |
2286 | event->pmu->del(event, 0); |
2287 | event->oncpu = -1; | |
0d3d73aa | 2288 | |
1d54ad94 PZ |
2289 | if (READ_ONCE(event->pending_disable) >= 0) { |
2290 | WRITE_ONCE(event->pending_disable, -1); | |
33238c50 | 2291 | perf_cgroup_event_disable(event, ctx); |
0d3d73aa | 2292 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2293 | } |
0d3d73aa | 2294 | perf_event_set_state(event, state); |
3b6f9e5c | 2295 | |
cdd6c482 | 2296 | if (!is_software_event(event)) |
3b6f9e5c | 2297 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2298 | if (!--ctx->nr_active) |
2299 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2300 | if (event->attr.freq && event->attr.sample_freq) |
2301 | ctx->nr_freq--; | |
cdd6c482 | 2302 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2303 | cpuctx->exclusive = 0; |
44377277 AS |
2304 | |
2305 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2306 | } |
2307 | ||
d859e29f | 2308 | static void |
cdd6c482 | 2309 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2310 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2311 | struct perf_event_context *ctx) |
d859e29f | 2312 | { |
cdd6c482 | 2313 | struct perf_event *event; |
0d3d73aa PZ |
2314 | |
2315 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2316 | return; | |
d859e29f | 2317 | |
3f005e7d MR |
2318 | perf_pmu_disable(ctx->pmu); |
2319 | ||
cdd6c482 | 2320 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2321 | |
2322 | /* | |
2323 | * Schedule out siblings (if any): | |
2324 | */ | |
edb39592 | 2325 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2326 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2327 | |
3f005e7d | 2328 | perf_pmu_enable(ctx->pmu); |
d859e29f PM |
2329 | } |
2330 | ||
45a0e07a | 2331 | #define DETACH_GROUP 0x01UL |
0017960f | 2332 | |
0793a61d | 2333 | /* |
cdd6c482 | 2334 | * Cross CPU call to remove a performance event |
0793a61d | 2335 | * |
cdd6c482 | 2336 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2337 | * remove it from the context list. |
2338 | */ | |
fae3fde6 PZ |
2339 | static void |
2340 | __perf_remove_from_context(struct perf_event *event, | |
2341 | struct perf_cpu_context *cpuctx, | |
2342 | struct perf_event_context *ctx, | |
2343 | void *info) | |
0793a61d | 2344 | { |
45a0e07a | 2345 | unsigned long flags = (unsigned long)info; |
0793a61d | 2346 | |
3c5c8711 PZ |
2347 | if (ctx->is_active & EVENT_TIME) { |
2348 | update_context_time(ctx); | |
2349 | update_cgrp_time_from_cpuctx(cpuctx); | |
2350 | } | |
2351 | ||
cdd6c482 | 2352 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2353 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2354 | perf_group_detach(event); |
cdd6c482 | 2355 | list_del_event(event, ctx); |
39a43640 PZ |
2356 | |
2357 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2358 | ctx->is_active = 0; |
90c91dfb | 2359 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2360 | if (ctx->task) { |
2361 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2362 | cpuctx->task_ctx = NULL; | |
2363 | } | |
64ce3126 | 2364 | } |
0793a61d TG |
2365 | } |
2366 | ||
0793a61d | 2367 | /* |
cdd6c482 | 2368 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2369 | * |
cdd6c482 IM |
2370 | * If event->ctx is a cloned context, callers must make sure that |
2371 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2372 | * remains valid. This is OK when called from perf_release since |
2373 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2374 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2375 | * context has been detached from its task. |
0793a61d | 2376 | */ |
45a0e07a | 2377 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2378 | { |
a76a82a3 PZ |
2379 | struct perf_event_context *ctx = event->ctx; |
2380 | ||
2381 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2382 | |
45a0e07a | 2383 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2384 | |
2385 | /* | |
2386 | * The above event_function_call() can NO-OP when it hits | |
2387 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2388 | * from the context (by perf_event_exit_event()) but the grouping | |
2389 | * might still be in-tact. | |
2390 | */ | |
2391 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2392 | if ((flags & DETACH_GROUP) && | |
2393 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2394 | /* | |
2395 | * Since in that case we cannot possibly be scheduled, simply | |
2396 | * detach now. | |
2397 | */ | |
2398 | raw_spin_lock_irq(&ctx->lock); | |
2399 | perf_group_detach(event); | |
2400 | raw_spin_unlock_irq(&ctx->lock); | |
2401 | } | |
0793a61d TG |
2402 | } |
2403 | ||
d859e29f | 2404 | /* |
cdd6c482 | 2405 | * Cross CPU call to disable a performance event |
d859e29f | 2406 | */ |
fae3fde6 PZ |
2407 | static void __perf_event_disable(struct perf_event *event, |
2408 | struct perf_cpu_context *cpuctx, | |
2409 | struct perf_event_context *ctx, | |
2410 | void *info) | |
7b648018 | 2411 | { |
fae3fde6 PZ |
2412 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2413 | return; | |
7b648018 | 2414 | |
3c5c8711 PZ |
2415 | if (ctx->is_active & EVENT_TIME) { |
2416 | update_context_time(ctx); | |
2417 | update_cgrp_time_from_event(event); | |
2418 | } | |
2419 | ||
fae3fde6 PZ |
2420 | if (event == event->group_leader) |
2421 | group_sched_out(event, cpuctx, ctx); | |
2422 | else | |
2423 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2424 | |
2425 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
33238c50 | 2426 | perf_cgroup_event_disable(event, ctx); |
7b648018 PZ |
2427 | } |
2428 | ||
d859e29f | 2429 | /* |
788faab7 | 2430 | * Disable an event. |
c93f7669 | 2431 | * |
cdd6c482 IM |
2432 | * If event->ctx is a cloned context, callers must make sure that |
2433 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2434 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2435 | * perf_event_for_each_child or perf_event_for_each because they |
2436 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2437 | * goes to exit will block in perf_event_exit_event(). |
2438 | * | |
cdd6c482 | 2439 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2440 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2441 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2442 | */ |
f63a8daa | 2443 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2444 | { |
cdd6c482 | 2445 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2446 | |
e625cce1 | 2447 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2448 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2449 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2450 | return; |
53cfbf59 | 2451 | } |
e625cce1 | 2452 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2453 | |
fae3fde6 PZ |
2454 | event_function_call(event, __perf_event_disable, NULL); |
2455 | } | |
2456 | ||
2457 | void perf_event_disable_local(struct perf_event *event) | |
2458 | { | |
2459 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2460 | } |
f63a8daa PZ |
2461 | |
2462 | /* | |
2463 | * Strictly speaking kernel users cannot create groups and therefore this | |
2464 | * interface does not need the perf_event_ctx_lock() magic. | |
2465 | */ | |
2466 | void perf_event_disable(struct perf_event *event) | |
2467 | { | |
2468 | struct perf_event_context *ctx; | |
2469 | ||
2470 | ctx = perf_event_ctx_lock(event); | |
2471 | _perf_event_disable(event); | |
2472 | perf_event_ctx_unlock(event, ctx); | |
2473 | } | |
dcfce4a0 | 2474 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2475 | |
5aab90ce JO |
2476 | void perf_event_disable_inatomic(struct perf_event *event) |
2477 | { | |
1d54ad94 PZ |
2478 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2479 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2480 | irq_work_queue(&event->pending); |
2481 | } | |
2482 | ||
e5d1367f | 2483 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2484 | struct perf_event_context *ctx) |
e5d1367f SE |
2485 | { |
2486 | /* | |
2487 | * use the correct time source for the time snapshot | |
2488 | * | |
2489 | * We could get by without this by leveraging the | |
2490 | * fact that to get to this function, the caller | |
2491 | * has most likely already called update_context_time() | |
2492 | * and update_cgrp_time_xx() and thus both timestamp | |
2493 | * are identical (or very close). Given that tstamp is, | |
2494 | * already adjusted for cgroup, we could say that: | |
2495 | * tstamp - ctx->timestamp | |
2496 | * is equivalent to | |
2497 | * tstamp - cgrp->timestamp. | |
2498 | * | |
2499 | * Then, in perf_output_read(), the calculation would | |
2500 | * work with no changes because: | |
2501 | * - event is guaranteed scheduled in | |
2502 | * - no scheduled out in between | |
2503 | * - thus the timestamp would be the same | |
2504 | * | |
2505 | * But this is a bit hairy. | |
2506 | * | |
2507 | * So instead, we have an explicit cgroup call to remain | |
2508 | * within the time time source all along. We believe it | |
2509 | * is cleaner and simpler to understand. | |
2510 | */ | |
2511 | if (is_cgroup_event(event)) | |
0d3d73aa | 2512 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2513 | else |
0d3d73aa | 2514 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2515 | } |
2516 | ||
4fe757dd PZ |
2517 | #define MAX_INTERRUPTS (~0ULL) |
2518 | ||
2519 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2520 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2521 | |
235c7fc7 | 2522 | static int |
9ffcfa6f | 2523 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2524 | struct perf_cpu_context *cpuctx, |
6e37738a | 2525 | struct perf_event_context *ctx) |
235c7fc7 | 2526 | { |
44377277 | 2527 | int ret = 0; |
4158755d | 2528 | |
ab6f824c PZ |
2529 | WARN_ON_ONCE(event->ctx != ctx); |
2530 | ||
63342411 PZ |
2531 | lockdep_assert_held(&ctx->lock); |
2532 | ||
cdd6c482 | 2533 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2534 | return 0; |
2535 | ||
95ff4ca2 AS |
2536 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2537 | /* | |
0c1cbc18 PZ |
2538 | * Order event::oncpu write to happen before the ACTIVE state is |
2539 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2540 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2541 | */ |
2542 | smp_wmb(); | |
0d3d73aa | 2543 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2544 | |
2545 | /* | |
2546 | * Unthrottle events, since we scheduled we might have missed several | |
2547 | * ticks already, also for a heavily scheduling task there is little | |
2548 | * guarantee it'll get a tick in a timely manner. | |
2549 | */ | |
2550 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2551 | perf_log_throttle(event, 1); | |
2552 | event->hw.interrupts = 0; | |
2553 | } | |
2554 | ||
44377277 AS |
2555 | perf_pmu_disable(event->pmu); |
2556 | ||
0d3d73aa | 2557 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2558 | |
ec0d7729 AS |
2559 | perf_log_itrace_start(event); |
2560 | ||
a4eaf7f1 | 2561 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2562 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2563 | event->oncpu = -1; |
44377277 AS |
2564 | ret = -EAGAIN; |
2565 | goto out; | |
235c7fc7 IM |
2566 | } |
2567 | ||
cdd6c482 | 2568 | if (!is_software_event(event)) |
3b6f9e5c | 2569 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2570 | if (!ctx->nr_active++) |
2571 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2572 | if (event->attr.freq && event->attr.sample_freq) |
2573 | ctx->nr_freq++; | |
235c7fc7 | 2574 | |
cdd6c482 | 2575 | if (event->attr.exclusive) |
3b6f9e5c PM |
2576 | cpuctx->exclusive = 1; |
2577 | ||
44377277 AS |
2578 | out: |
2579 | perf_pmu_enable(event->pmu); | |
2580 | ||
2581 | return ret; | |
235c7fc7 IM |
2582 | } |
2583 | ||
6751b71e | 2584 | static int |
cdd6c482 | 2585 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2586 | struct perf_cpu_context *cpuctx, |
6e37738a | 2587 | struct perf_event_context *ctx) |
6751b71e | 2588 | { |
6bde9b6c | 2589 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2590 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2591 | |
cdd6c482 | 2592 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2593 | return 0; |
2594 | ||
fbbe0701 | 2595 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2596 | |
251ff2d4 PZ |
2597 | if (event_sched_in(group_event, cpuctx, ctx)) |
2598 | goto error; | |
6751b71e PM |
2599 | |
2600 | /* | |
2601 | * Schedule in siblings as one group (if any): | |
2602 | */ | |
edb39592 | 2603 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2604 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2605 | partial_group = event; |
6751b71e PM |
2606 | goto group_error; |
2607 | } | |
2608 | } | |
2609 | ||
9ffcfa6f | 2610 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2611 | return 0; |
9ffcfa6f | 2612 | |
6751b71e PM |
2613 | group_error: |
2614 | /* | |
2615 | * Groups can be scheduled in as one unit only, so undo any | |
2616 | * partial group before returning: | |
0d3d73aa | 2617 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2618 | */ |
edb39592 | 2619 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2620 | if (event == partial_group) |
0d3d73aa | 2621 | break; |
d7842da4 | 2622 | |
0d3d73aa | 2623 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2624 | } |
9ffcfa6f | 2625 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2626 | |
251ff2d4 | 2627 | error: |
ad5133b7 | 2628 | pmu->cancel_txn(pmu); |
6751b71e PM |
2629 | return -EAGAIN; |
2630 | } | |
2631 | ||
3b6f9e5c | 2632 | /* |
cdd6c482 | 2633 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2634 | */ |
cdd6c482 | 2635 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2636 | struct perf_cpu_context *cpuctx, |
2637 | int can_add_hw) | |
2638 | { | |
2639 | /* | |
cdd6c482 | 2640 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2641 | */ |
4ff6a8de | 2642 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2643 | return 1; |
2644 | /* | |
2645 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2646 | * events can go on. |
3b6f9e5c PM |
2647 | */ |
2648 | if (cpuctx->exclusive) | |
2649 | return 0; | |
2650 | /* | |
2651 | * If this group is exclusive and there are already | |
cdd6c482 | 2652 | * events on the CPU, it can't go on. |
3b6f9e5c | 2653 | */ |
1908dc91 | 2654 | if (event->attr.exclusive && !list_empty(get_event_list(event))) |
3b6f9e5c PM |
2655 | return 0; |
2656 | /* | |
2657 | * Otherwise, try to add it if all previous groups were able | |
2658 | * to go on. | |
2659 | */ | |
2660 | return can_add_hw; | |
2661 | } | |
2662 | ||
cdd6c482 IM |
2663 | static void add_event_to_ctx(struct perf_event *event, |
2664 | struct perf_event_context *ctx) | |
53cfbf59 | 2665 | { |
cdd6c482 | 2666 | list_add_event(event, ctx); |
8a49542c | 2667 | perf_group_attach(event); |
53cfbf59 PM |
2668 | } |
2669 | ||
bd2afa49 PZ |
2670 | static void ctx_sched_out(struct perf_event_context *ctx, |
2671 | struct perf_cpu_context *cpuctx, | |
2672 | enum event_type_t event_type); | |
2c29ef0f PZ |
2673 | static void |
2674 | ctx_sched_in(struct perf_event_context *ctx, | |
2675 | struct perf_cpu_context *cpuctx, | |
2676 | enum event_type_t event_type, | |
2677 | struct task_struct *task); | |
fe4b04fa | 2678 | |
bd2afa49 | 2679 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2680 | struct perf_event_context *ctx, |
2681 | enum event_type_t event_type) | |
bd2afa49 PZ |
2682 | { |
2683 | if (!cpuctx->task_ctx) | |
2684 | return; | |
2685 | ||
2686 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2687 | return; | |
2688 | ||
487f05e1 | 2689 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2690 | } |
2691 | ||
dce5855b PZ |
2692 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2693 | struct perf_event_context *ctx, | |
2694 | struct task_struct *task) | |
2695 | { | |
2696 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2697 | if (ctx) | |
2698 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2699 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2700 | if (ctx) | |
2701 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2702 | } | |
2703 | ||
487f05e1 AS |
2704 | /* |
2705 | * We want to maintain the following priority of scheduling: | |
2706 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2707 | * - task pinned (EVENT_PINNED) | |
2708 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2709 | * - task flexible (EVENT_FLEXIBLE). | |
2710 | * | |
2711 | * In order to avoid unscheduling and scheduling back in everything every | |
2712 | * time an event is added, only do it for the groups of equal priority and | |
2713 | * below. | |
2714 | * | |
2715 | * This can be called after a batch operation on task events, in which case | |
2716 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2717 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2718 | */ | |
3e349507 | 2719 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2720 | struct perf_event_context *task_ctx, |
2721 | enum event_type_t event_type) | |
0017960f | 2722 | { |
bd903afe | 2723 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2724 | bool cpu_event = !!(event_type & EVENT_CPU); |
2725 | ||
2726 | /* | |
2727 | * If pinned groups are involved, flexible groups also need to be | |
2728 | * scheduled out. | |
2729 | */ | |
2730 | if (event_type & EVENT_PINNED) | |
2731 | event_type |= EVENT_FLEXIBLE; | |
2732 | ||
bd903afe SL |
2733 | ctx_event_type = event_type & EVENT_ALL; |
2734 | ||
3e349507 PZ |
2735 | perf_pmu_disable(cpuctx->ctx.pmu); |
2736 | if (task_ctx) | |
487f05e1 AS |
2737 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2738 | ||
2739 | /* | |
2740 | * Decide which cpu ctx groups to schedule out based on the types | |
2741 | * of events that caused rescheduling: | |
2742 | * - EVENT_CPU: schedule out corresponding groups; | |
2743 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2744 | * - otherwise, do nothing more. | |
2745 | */ | |
2746 | if (cpu_event) | |
2747 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2748 | else if (ctx_event_type & EVENT_PINNED) | |
2749 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2750 | ||
3e349507 PZ |
2751 | perf_event_sched_in(cpuctx, task_ctx, current); |
2752 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2753 | } |
2754 | ||
c68d224e SE |
2755 | void perf_pmu_resched(struct pmu *pmu) |
2756 | { | |
2757 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2758 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2759 | ||
2760 | perf_ctx_lock(cpuctx, task_ctx); | |
2761 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2762 | perf_ctx_unlock(cpuctx, task_ctx); | |
2763 | } | |
2764 | ||
0793a61d | 2765 | /* |
cdd6c482 | 2766 | * Cross CPU call to install and enable a performance event |
682076ae | 2767 | * |
a096309b PZ |
2768 | * Very similar to remote_function() + event_function() but cannot assume that |
2769 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2770 | */ |
fe4b04fa | 2771 | static int __perf_install_in_context(void *info) |
0793a61d | 2772 | { |
a096309b PZ |
2773 | struct perf_event *event = info; |
2774 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2775 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2776 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2777 | bool reprogram = true; |
a096309b | 2778 | int ret = 0; |
0793a61d | 2779 | |
63b6da39 | 2780 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2781 | if (ctx->task) { |
b58f6b0d PZ |
2782 | raw_spin_lock(&ctx->lock); |
2783 | task_ctx = ctx; | |
a096309b | 2784 | |
63cae12b | 2785 | reprogram = (ctx->task == current); |
b58f6b0d | 2786 | |
39a43640 | 2787 | /* |
63cae12b PZ |
2788 | * If the task is running, it must be running on this CPU, |
2789 | * otherwise we cannot reprogram things. | |
2790 | * | |
2791 | * If its not running, we don't care, ctx->lock will | |
2792 | * serialize against it becoming runnable. | |
39a43640 | 2793 | */ |
63cae12b PZ |
2794 | if (task_curr(ctx->task) && !reprogram) { |
2795 | ret = -ESRCH; | |
2796 | goto unlock; | |
2797 | } | |
a096309b | 2798 | |
63cae12b | 2799 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2800 | } else if (task_ctx) { |
2801 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2802 | } |
b58f6b0d | 2803 | |
33801b94 | 2804 | #ifdef CONFIG_CGROUP_PERF |
33238c50 | 2805 | if (event->state > PERF_EVENT_STATE_OFF && is_cgroup_event(event)) { |
33801b94 | 2806 | /* |
2807 | * If the current cgroup doesn't match the event's | |
2808 | * cgroup, we should not try to schedule it. | |
2809 | */ | |
2810 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2811 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2812 | event->cgrp->css.cgroup); | |
2813 | } | |
2814 | #endif | |
2815 | ||
63cae12b | 2816 | if (reprogram) { |
a096309b PZ |
2817 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2818 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2819 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2820 | } else { |
2821 | add_event_to_ctx(event, ctx); | |
2822 | } | |
2823 | ||
63b6da39 | 2824 | unlock: |
2c29ef0f | 2825 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2826 | |
a096309b | 2827 | return ret; |
0793a61d TG |
2828 | } |
2829 | ||
8a58ddae AS |
2830 | static bool exclusive_event_installable(struct perf_event *event, |
2831 | struct perf_event_context *ctx); | |
2832 | ||
0793a61d | 2833 | /* |
a096309b PZ |
2834 | * Attach a performance event to a context. |
2835 | * | |
2836 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2837 | */ |
2838 | static void | |
cdd6c482 IM |
2839 | perf_install_in_context(struct perf_event_context *ctx, |
2840 | struct perf_event *event, | |
0793a61d TG |
2841 | int cpu) |
2842 | { | |
a096309b | 2843 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2844 | |
fe4b04fa PZ |
2845 | lockdep_assert_held(&ctx->mutex); |
2846 | ||
8a58ddae AS |
2847 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2848 | ||
0cda4c02 YZ |
2849 | if (event->cpu != -1) |
2850 | event->cpu = cpu; | |
c3f00c70 | 2851 | |
0b8f1e2e PZ |
2852 | /* |
2853 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2854 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2855 | */ | |
2856 | smp_store_release(&event->ctx, ctx); | |
2857 | ||
db0503e4 PZ |
2858 | /* |
2859 | * perf_event_attr::disabled events will not run and can be initialized | |
2860 | * without IPI. Except when this is the first event for the context, in | |
2861 | * that case we need the magic of the IPI to set ctx->is_active. | |
2862 | * | |
2863 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2864 | * event will issue the IPI and reprogram the hardware. | |
2865 | */ | |
2866 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2867 | raw_spin_lock_irq(&ctx->lock); | |
2868 | if (ctx->task == TASK_TOMBSTONE) { | |
2869 | raw_spin_unlock_irq(&ctx->lock); | |
2870 | return; | |
2871 | } | |
2872 | add_event_to_ctx(event, ctx); | |
2873 | raw_spin_unlock_irq(&ctx->lock); | |
2874 | return; | |
2875 | } | |
2876 | ||
a096309b PZ |
2877 | if (!task) { |
2878 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2879 | return; | |
2880 | } | |
2881 | ||
2882 | /* | |
2883 | * Should not happen, we validate the ctx is still alive before calling. | |
2884 | */ | |
2885 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2886 | return; | |
2887 | ||
39a43640 PZ |
2888 | /* |
2889 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2890 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2891 | * |
2892 | * Instead we use task_curr(), which tells us if the task is running. | |
2893 | * However, since we use task_curr() outside of rq::lock, we can race | |
2894 | * against the actual state. This means the result can be wrong. | |
2895 | * | |
2896 | * If we get a false positive, we retry, this is harmless. | |
2897 | * | |
2898 | * If we get a false negative, things are complicated. If we are after | |
2899 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2900 | * value must be correct. If we're before, it doesn't matter since | |
2901 | * perf_event_context_sched_in() will program the counter. | |
2902 | * | |
2903 | * However, this hinges on the remote context switch having observed | |
2904 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2905 | * ctx::lock in perf_event_context_sched_in(). | |
2906 | * | |
2907 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2908 | * we know any future context switch of task must see the | |
2909 | * perf_event_ctpx[] store. | |
39a43640 | 2910 | */ |
63cae12b | 2911 | |
63b6da39 | 2912 | /* |
63cae12b PZ |
2913 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2914 | * task_cpu() load, such that if the IPI then does not find the task | |
2915 | * running, a future context switch of that task must observe the | |
2916 | * store. | |
63b6da39 | 2917 | */ |
63cae12b PZ |
2918 | smp_mb(); |
2919 | again: | |
2920 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2921 | return; |
2922 | ||
2923 | raw_spin_lock_irq(&ctx->lock); | |
2924 | task = ctx->task; | |
84c4e620 | 2925 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2926 | /* |
2927 | * Cannot happen because we already checked above (which also | |
2928 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2929 | * against perf_event_exit_task_context(). | |
2930 | */ | |
63b6da39 PZ |
2931 | raw_spin_unlock_irq(&ctx->lock); |
2932 | return; | |
2933 | } | |
39a43640 | 2934 | /* |
63cae12b PZ |
2935 | * If the task is not running, ctx->lock will avoid it becoming so, |
2936 | * thus we can safely install the event. | |
39a43640 | 2937 | */ |
63cae12b PZ |
2938 | if (task_curr(task)) { |
2939 | raw_spin_unlock_irq(&ctx->lock); | |
2940 | goto again; | |
2941 | } | |
2942 | add_event_to_ctx(event, ctx); | |
2943 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2944 | } |
2945 | ||
d859e29f | 2946 | /* |
cdd6c482 | 2947 | * Cross CPU call to enable a performance event |
d859e29f | 2948 | */ |
fae3fde6 PZ |
2949 | static void __perf_event_enable(struct perf_event *event, |
2950 | struct perf_cpu_context *cpuctx, | |
2951 | struct perf_event_context *ctx, | |
2952 | void *info) | |
04289bb9 | 2953 | { |
cdd6c482 | 2954 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2955 | struct perf_event_context *task_ctx; |
04289bb9 | 2956 | |
6e801e01 PZ |
2957 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2958 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2959 | return; |
3cbed429 | 2960 | |
bd2afa49 PZ |
2961 | if (ctx->is_active) |
2962 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2963 | ||
0d3d73aa | 2964 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
33238c50 | 2965 | perf_cgroup_event_enable(event, ctx); |
04289bb9 | 2966 | |
fae3fde6 PZ |
2967 | if (!ctx->is_active) |
2968 | return; | |
2969 | ||
e5d1367f | 2970 | if (!event_filter_match(event)) { |
bd2afa49 | 2971 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2972 | return; |
e5d1367f | 2973 | } |
f4c4176f | 2974 | |
04289bb9 | 2975 | /* |
cdd6c482 | 2976 | * If the event is in a group and isn't the group leader, |
d859e29f | 2977 | * then don't put it on unless the group is on. |
04289bb9 | 2978 | */ |
bd2afa49 PZ |
2979 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2980 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2981 | return; |
bd2afa49 | 2982 | } |
fe4b04fa | 2983 | |
fae3fde6 PZ |
2984 | task_ctx = cpuctx->task_ctx; |
2985 | if (ctx->task) | |
2986 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2987 | |
487f05e1 | 2988 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2989 | } |
2990 | ||
d859e29f | 2991 | /* |
788faab7 | 2992 | * Enable an event. |
c93f7669 | 2993 | * |
cdd6c482 IM |
2994 | * If event->ctx is a cloned context, callers must make sure that |
2995 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2996 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2997 | * perf_event_for_each_child or perf_event_for_each as described |
2998 | * for perf_event_disable. | |
d859e29f | 2999 | */ |
f63a8daa | 3000 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 3001 | { |
cdd6c482 | 3002 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 3003 | |
7b648018 | 3004 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
3005 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
3006 | event->state < PERF_EVENT_STATE_ERROR) { | |
9f0c4fa1 | 3007 | out: |
7b648018 | 3008 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
3009 | return; |
3010 | } | |
3011 | ||
d859e29f | 3012 | /* |
cdd6c482 | 3013 | * If the event is in error state, clear that first. |
7b648018 PZ |
3014 | * |
3015 | * That way, if we see the event in error state below, we know that it | |
3016 | * has gone back into error state, as distinct from the task having | |
3017 | * been scheduled away before the cross-call arrived. | |
d859e29f | 3018 | */ |
9f0c4fa1 KL |
3019 | if (event->state == PERF_EVENT_STATE_ERROR) { |
3020 | /* | |
3021 | * Detached SIBLING events cannot leave ERROR state. | |
3022 | */ | |
3023 | if (event->event_caps & PERF_EV_CAP_SIBLING && | |
3024 | event->group_leader == event) | |
3025 | goto out; | |
3026 | ||
cdd6c482 | 3027 | event->state = PERF_EVENT_STATE_OFF; |
9f0c4fa1 | 3028 | } |
e625cce1 | 3029 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 3030 | |
fae3fde6 | 3031 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 3032 | } |
f63a8daa PZ |
3033 | |
3034 | /* | |
3035 | * See perf_event_disable(); | |
3036 | */ | |
3037 | void perf_event_enable(struct perf_event *event) | |
3038 | { | |
3039 | struct perf_event_context *ctx; | |
3040 | ||
3041 | ctx = perf_event_ctx_lock(event); | |
3042 | _perf_event_enable(event); | |
3043 | perf_event_ctx_unlock(event, ctx); | |
3044 | } | |
dcfce4a0 | 3045 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 3046 | |
375637bc AS |
3047 | struct stop_event_data { |
3048 | struct perf_event *event; | |
3049 | unsigned int restart; | |
3050 | }; | |
3051 | ||
95ff4ca2 AS |
3052 | static int __perf_event_stop(void *info) |
3053 | { | |
375637bc AS |
3054 | struct stop_event_data *sd = info; |
3055 | struct perf_event *event = sd->event; | |
95ff4ca2 | 3056 | |
375637bc | 3057 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
3058 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
3059 | return 0; | |
3060 | ||
3061 | /* matches smp_wmb() in event_sched_in() */ | |
3062 | smp_rmb(); | |
3063 | ||
3064 | /* | |
3065 | * There is a window with interrupts enabled before we get here, | |
3066 | * so we need to check again lest we try to stop another CPU's event. | |
3067 | */ | |
3068 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3069 | return -EAGAIN; | |
3070 | ||
3071 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3072 | ||
375637bc AS |
3073 | /* |
3074 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3075 | * but it is only used for events with AUX ring buffer, and such | |
3076 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3077 | * see comments in perf_aux_output_begin(). | |
3078 | * | |
788faab7 | 3079 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3080 | * while restarting. |
3081 | */ | |
3082 | if (sd->restart) | |
c9bbdd48 | 3083 | event->pmu->start(event, 0); |
375637bc | 3084 | |
95ff4ca2 AS |
3085 | return 0; |
3086 | } | |
3087 | ||
767ae086 | 3088 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3089 | { |
3090 | struct stop_event_data sd = { | |
3091 | .event = event, | |
767ae086 | 3092 | .restart = restart, |
375637bc AS |
3093 | }; |
3094 | int ret = 0; | |
3095 | ||
3096 | do { | |
3097 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3098 | return 0; | |
3099 | ||
3100 | /* matches smp_wmb() in event_sched_in() */ | |
3101 | smp_rmb(); | |
3102 | ||
3103 | /* | |
3104 | * We only want to restart ACTIVE events, so if the event goes | |
3105 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3106 | * fall through with ret==-ENXIO. | |
3107 | */ | |
3108 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3109 | __perf_event_stop, &sd); | |
3110 | } while (ret == -EAGAIN); | |
3111 | ||
3112 | return ret; | |
3113 | } | |
3114 | ||
3115 | /* | |
3116 | * In order to contain the amount of racy and tricky in the address filter | |
3117 | * configuration management, it is a two part process: | |
3118 | * | |
3119 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3120 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3121 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3122 | * (p2) when an event is scheduled in (pmu::add), it calls |
3123 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3124 | * if the generation has changed since the previous call. | |
3125 | * | |
3126 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3127 | * | |
3128 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3129 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3130 | * ioctl; | |
3131 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
c1e8d7c6 | 3132 | * registered mapping, called for every new mmap(), with mm::mmap_lock down |
375637bc AS |
3133 | * for reading; |
3134 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3135 | * of exec. | |
3136 | */ | |
3137 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3138 | { | |
3139 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3140 | ||
3141 | if (!has_addr_filter(event)) | |
3142 | return; | |
3143 | ||
3144 | raw_spin_lock(&ifh->lock); | |
3145 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3146 | event->pmu->addr_filters_sync(event); | |
3147 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3148 | } | |
3149 | raw_spin_unlock(&ifh->lock); | |
3150 | } | |
3151 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3152 | ||
f63a8daa | 3153 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3154 | { |
2023b359 | 3155 | /* |
cdd6c482 | 3156 | * not supported on inherited events |
2023b359 | 3157 | */ |
2e939d1d | 3158 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3159 | return -EINVAL; |
3160 | ||
cdd6c482 | 3161 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3162 | _perf_event_enable(event); |
2023b359 PZ |
3163 | |
3164 | return 0; | |
79f14641 | 3165 | } |
f63a8daa PZ |
3166 | |
3167 | /* | |
3168 | * See perf_event_disable() | |
3169 | */ | |
3170 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3171 | { | |
3172 | struct perf_event_context *ctx; | |
3173 | int ret; | |
3174 | ||
3175 | ctx = perf_event_ctx_lock(event); | |
3176 | ret = _perf_event_refresh(event, refresh); | |
3177 | perf_event_ctx_unlock(event, ctx); | |
3178 | ||
3179 | return ret; | |
3180 | } | |
26ca5c11 | 3181 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3182 | |
32ff77e8 MC |
3183 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3184 | struct perf_event_attr *attr) | |
3185 | { | |
3186 | int err; | |
3187 | ||
3188 | _perf_event_disable(bp); | |
3189 | ||
3190 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3191 | |
bf06278c | 3192 | if (!bp->attr.disabled) |
32ff77e8 | 3193 | _perf_event_enable(bp); |
bf06278c JO |
3194 | |
3195 | return err; | |
32ff77e8 MC |
3196 | } |
3197 | ||
3198 | static int perf_event_modify_attr(struct perf_event *event, | |
3199 | struct perf_event_attr *attr) | |
3200 | { | |
3201 | if (event->attr.type != attr->type) | |
3202 | return -EINVAL; | |
3203 | ||
3204 | switch (event->attr.type) { | |
3205 | case PERF_TYPE_BREAKPOINT: | |
3206 | return perf_event_modify_breakpoint(event, attr); | |
3207 | default: | |
3208 | /* Place holder for future additions. */ | |
3209 | return -EOPNOTSUPP; | |
3210 | } | |
3211 | } | |
3212 | ||
5b0311e1 FW |
3213 | static void ctx_sched_out(struct perf_event_context *ctx, |
3214 | struct perf_cpu_context *cpuctx, | |
3215 | enum event_type_t event_type) | |
235c7fc7 | 3216 | { |
6668128a | 3217 | struct perf_event *event, *tmp; |
db24d33e | 3218 | int is_active = ctx->is_active; |
235c7fc7 | 3219 | |
c994d613 | 3220 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3221 | |
39a43640 PZ |
3222 | if (likely(!ctx->nr_events)) { |
3223 | /* | |
3224 | * See __perf_remove_from_context(). | |
3225 | */ | |
3226 | WARN_ON_ONCE(ctx->is_active); | |
3227 | if (ctx->task) | |
3228 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3229 | return; |
39a43640 PZ |
3230 | } |
3231 | ||
db24d33e | 3232 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3233 | if (!(ctx->is_active & EVENT_ALL)) |
3234 | ctx->is_active = 0; | |
3235 | ||
63e30d3e PZ |
3236 | if (ctx->task) { |
3237 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3238 | if (!ctx->is_active) | |
3239 | cpuctx->task_ctx = NULL; | |
3240 | } | |
facc4307 | 3241 | |
8fdc6539 PZ |
3242 | /* |
3243 | * Always update time if it was set; not only when it changes. | |
3244 | * Otherwise we can 'forget' to update time for any but the last | |
3245 | * context we sched out. For example: | |
3246 | * | |
3247 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3248 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3249 | * | |
3250 | * would only update time for the pinned events. | |
3251 | */ | |
3cbaa590 PZ |
3252 | if (is_active & EVENT_TIME) { |
3253 | /* update (and stop) ctx time */ | |
3254 | update_context_time(ctx); | |
3255 | update_cgrp_time_from_cpuctx(cpuctx); | |
3256 | } | |
3257 | ||
8fdc6539 PZ |
3258 | is_active ^= ctx->is_active; /* changed bits */ |
3259 | ||
3cbaa590 | 3260 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3261 | return; |
5b0311e1 | 3262 | |
075e0b00 | 3263 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3264 | if (is_active & EVENT_PINNED) { |
6668128a | 3265 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3266 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3267 | } |
889ff015 | 3268 | |
3cbaa590 | 3269 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3270 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3271 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3272 | |
3273 | /* | |
3274 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3275 | * rotate_necessary, is will be reset by | |
3276 | * ctx_flexible_sched_in() when needed. | |
3277 | */ | |
3278 | ctx->rotate_necessary = 0; | |
9ed6060d | 3279 | } |
1b9a644f | 3280 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3281 | } |
3282 | ||
564c2b21 | 3283 | /* |
5a3126d4 PZ |
3284 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3285 | * cloned from the same version of the same context. | |
3286 | * | |
3287 | * Equivalence is measured using a generation number in the context that is | |
3288 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3289 | * and list_del_event(). | |
564c2b21 | 3290 | */ |
cdd6c482 IM |
3291 | static int context_equiv(struct perf_event_context *ctx1, |
3292 | struct perf_event_context *ctx2) | |
564c2b21 | 3293 | { |
211de6eb PZ |
3294 | lockdep_assert_held(&ctx1->lock); |
3295 | lockdep_assert_held(&ctx2->lock); | |
3296 | ||
5a3126d4 PZ |
3297 | /* Pinning disables the swap optimization */ |
3298 | if (ctx1->pin_count || ctx2->pin_count) | |
3299 | return 0; | |
3300 | ||
3301 | /* If ctx1 is the parent of ctx2 */ | |
3302 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3303 | return 1; | |
3304 | ||
3305 | /* If ctx2 is the parent of ctx1 */ | |
3306 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3307 | return 1; | |
3308 | ||
3309 | /* | |
3310 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3311 | * hierarchy, see perf_event_init_context(). | |
3312 | */ | |
3313 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3314 | ctx1->parent_gen == ctx2->parent_gen) | |
3315 | return 1; | |
3316 | ||
3317 | /* Unmatched */ | |
3318 | return 0; | |
564c2b21 PM |
3319 | } |
3320 | ||
cdd6c482 IM |
3321 | static void __perf_event_sync_stat(struct perf_event *event, |
3322 | struct perf_event *next_event) | |
bfbd3381 PZ |
3323 | { |
3324 | u64 value; | |
3325 | ||
cdd6c482 | 3326 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3327 | return; |
3328 | ||
3329 | /* | |
cdd6c482 | 3330 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3331 | * because we're in the middle of a context switch and have IRQs |
3332 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3333 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3334 | * don't need to use it. |
3335 | */ | |
0d3d73aa | 3336 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3337 | event->pmu->read(event); |
bfbd3381 | 3338 | |
0d3d73aa | 3339 | perf_event_update_time(event); |
bfbd3381 PZ |
3340 | |
3341 | /* | |
cdd6c482 | 3342 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3343 | * values when we flip the contexts. |
3344 | */ | |
e7850595 PZ |
3345 | value = local64_read(&next_event->count); |
3346 | value = local64_xchg(&event->count, value); | |
3347 | local64_set(&next_event->count, value); | |
bfbd3381 | 3348 | |
cdd6c482 IM |
3349 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3350 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3351 | |
bfbd3381 | 3352 | /* |
19d2e755 | 3353 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3354 | */ |
cdd6c482 IM |
3355 | perf_event_update_userpage(event); |
3356 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3357 | } |
3358 | ||
cdd6c482 IM |
3359 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3360 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3361 | { |
cdd6c482 | 3362 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3363 | |
3364 | if (!ctx->nr_stat) | |
3365 | return; | |
3366 | ||
02ffdbc8 PZ |
3367 | update_context_time(ctx); |
3368 | ||
cdd6c482 IM |
3369 | event = list_first_entry(&ctx->event_list, |
3370 | struct perf_event, event_entry); | |
bfbd3381 | 3371 | |
cdd6c482 IM |
3372 | next_event = list_first_entry(&next_ctx->event_list, |
3373 | struct perf_event, event_entry); | |
bfbd3381 | 3374 | |
cdd6c482 IM |
3375 | while (&event->event_entry != &ctx->event_list && |
3376 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3377 | |
cdd6c482 | 3378 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3379 | |
cdd6c482 IM |
3380 | event = list_next_entry(event, event_entry); |
3381 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3382 | } |
3383 | } | |
3384 | ||
fe4b04fa PZ |
3385 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3386 | struct task_struct *next) | |
0793a61d | 3387 | { |
8dc85d54 | 3388 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3389 | struct perf_event_context *next_ctx; |
5a3126d4 | 3390 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3391 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3392 | int do_switch = 1; |
44fae179 | 3393 | struct pmu *pmu; |
0793a61d | 3394 | |
108b02cf PZ |
3395 | if (likely(!ctx)) |
3396 | return; | |
10989fb2 | 3397 | |
44fae179 | 3398 | pmu = ctx->pmu; |
108b02cf PZ |
3399 | cpuctx = __get_cpu_context(ctx); |
3400 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3401 | return; |
3402 | ||
c93f7669 | 3403 | rcu_read_lock(); |
8dc85d54 | 3404 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3405 | if (!next_ctx) |
3406 | goto unlock; | |
3407 | ||
3408 | parent = rcu_dereference(ctx->parent_ctx); | |
3409 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3410 | ||
3411 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3412 | if (!parent && !next_parent) |
5a3126d4 PZ |
3413 | goto unlock; |
3414 | ||
3415 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3416 | /* |
3417 | * Looks like the two contexts are clones, so we might be | |
3418 | * able to optimize the context switch. We lock both | |
3419 | * contexts and check that they are clones under the | |
3420 | * lock (including re-checking that neither has been | |
3421 | * uncloned in the meantime). It doesn't matter which | |
3422 | * order we take the locks because no other cpu could | |
3423 | * be trying to lock both of these tasks. | |
3424 | */ | |
e625cce1 TG |
3425 | raw_spin_lock(&ctx->lock); |
3426 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3427 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 | 3428 | |
63b6da39 PZ |
3429 | WRITE_ONCE(ctx->task, next); |
3430 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3431 | |
44fae179 KL |
3432 | perf_pmu_disable(pmu); |
3433 | ||
3434 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3435 | pmu->sched_task(ctx, false); | |
3436 | ||
c2b98a86 AB |
3437 | /* |
3438 | * PMU specific parts of task perf context can require | |
3439 | * additional synchronization. As an example of such | |
3440 | * synchronization see implementation details of Intel | |
3441 | * LBR call stack data profiling; | |
3442 | */ | |
3443 | if (pmu->swap_task_ctx) | |
3444 | pmu->swap_task_ctx(ctx, next_ctx); | |
3445 | else | |
3446 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3447 | |
44fae179 KL |
3448 | perf_pmu_enable(pmu); |
3449 | ||
63b6da39 PZ |
3450 | /* |
3451 | * RCU_INIT_POINTER here is safe because we've not | |
3452 | * modified the ctx and the above modification of | |
3453 | * ctx->task and ctx->task_ctx_data are immaterial | |
3454 | * since those values are always verified under | |
3455 | * ctx->lock which we're now holding. | |
3456 | */ | |
3457 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3458 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3459 | ||
c93f7669 | 3460 | do_switch = 0; |
bfbd3381 | 3461 | |
cdd6c482 | 3462 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3463 | } |
e625cce1 TG |
3464 | raw_spin_unlock(&next_ctx->lock); |
3465 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3466 | } |
5a3126d4 | 3467 | unlock: |
c93f7669 | 3468 | rcu_read_unlock(); |
564c2b21 | 3469 | |
c93f7669 | 3470 | if (do_switch) { |
facc4307 | 3471 | raw_spin_lock(&ctx->lock); |
44fae179 KL |
3472 | perf_pmu_disable(pmu); |
3473 | ||
3474 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3475 | pmu->sched_task(ctx, false); | |
487f05e1 | 3476 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
44fae179 KL |
3477 | |
3478 | perf_pmu_enable(pmu); | |
facc4307 | 3479 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3480 | } |
0793a61d TG |
3481 | } |
3482 | ||
f008790a KL |
3483 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3484 | ||
ba532500 YZ |
3485 | void perf_sched_cb_dec(struct pmu *pmu) |
3486 | { | |
e48c1788 PZ |
3487 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3488 | ||
f008790a KL |
3489 | this_cpu_dec(perf_sched_cb_usages); |
3490 | ||
3491 | if (!--cpuctx->sched_cb_usage) | |
3492 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3493 | } |
3494 | ||
e48c1788 | 3495 | |
ba532500 YZ |
3496 | void perf_sched_cb_inc(struct pmu *pmu) |
3497 | { | |
e48c1788 PZ |
3498 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3499 | ||
f008790a KL |
3500 | if (!cpuctx->sched_cb_usage++) |
3501 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3502 | ||
3503 | this_cpu_inc(perf_sched_cb_usages); | |
ba532500 YZ |
3504 | } |
3505 | ||
3506 | /* | |
3507 | * This function provides the context switch callback to the lower code | |
3508 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3509 | * |
3510 | * This callback is relevant even to per-cpu events; for example multi event | |
3511 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3512 | * all queued PEBS records before we context switch to a new task. | |
ba532500 | 3513 | */ |
556cccad KL |
3514 | static void __perf_pmu_sched_task(struct perf_cpu_context *cpuctx, bool sched_in) |
3515 | { | |
3516 | struct pmu *pmu; | |
3517 | ||
3518 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ | |
3519 | ||
3520 | if (WARN_ON_ONCE(!pmu->sched_task)) | |
3521 | return; | |
3522 | ||
3523 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
3524 | perf_pmu_disable(pmu); | |
3525 | ||
3526 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
3527 | ||
3528 | perf_pmu_enable(pmu); | |
3529 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
3530 | } | |
3531 | ||
f008790a KL |
3532 | static void perf_pmu_sched_task(struct task_struct *prev, |
3533 | struct task_struct *next, | |
3534 | bool sched_in) | |
3535 | { | |
3536 | struct perf_cpu_context *cpuctx; | |
3537 | ||
3538 | if (prev == next) | |
3539 | return; | |
3540 | ||
3541 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { | |
3542 | /* will be handled in perf_event_context_sched_in/out */ | |
3543 | if (cpuctx->task_ctx) | |
3544 | continue; | |
3545 | ||
3546 | __perf_pmu_sched_task(cpuctx, sched_in); | |
3547 | } | |
3548 | } | |
3549 | ||
45ac1403 AH |
3550 | static void perf_event_switch(struct task_struct *task, |
3551 | struct task_struct *next_prev, bool sched_in); | |
3552 | ||
8dc85d54 PZ |
3553 | #define for_each_task_context_nr(ctxn) \ |
3554 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3555 | ||
3556 | /* | |
3557 | * Called from scheduler to remove the events of the current task, | |
3558 | * with interrupts disabled. | |
3559 | * | |
3560 | * We stop each event and update the event value in event->count. | |
3561 | * | |
3562 | * This does not protect us against NMI, but disable() | |
3563 | * sets the disabled bit in the control field of event _before_ | |
3564 | * accessing the event control register. If a NMI hits, then it will | |
3565 | * not restart the event. | |
3566 | */ | |
ab0cce56 JO |
3567 | void __perf_event_task_sched_out(struct task_struct *task, |
3568 | struct task_struct *next) | |
8dc85d54 PZ |
3569 | { |
3570 | int ctxn; | |
3571 | ||
f008790a KL |
3572 | if (__this_cpu_read(perf_sched_cb_usages)) |
3573 | perf_pmu_sched_task(task, next, false); | |
3574 | ||
45ac1403 AH |
3575 | if (atomic_read(&nr_switch_events)) |
3576 | perf_event_switch(task, next, false); | |
3577 | ||
8dc85d54 PZ |
3578 | for_each_task_context_nr(ctxn) |
3579 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3580 | |
3581 | /* | |
3582 | * if cgroup events exist on this CPU, then we need | |
3583 | * to check if we have to switch out PMU state. | |
3584 | * cgroup event are system-wide mode only | |
3585 | */ | |
4a32fea9 | 3586 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3587 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3588 | } |
3589 | ||
5b0311e1 FW |
3590 | /* |
3591 | * Called with IRQs disabled | |
3592 | */ | |
3593 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3594 | enum event_type_t event_type) | |
3595 | { | |
3596 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3597 | } |
3598 | ||
6eef8a71 | 3599 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3600 | { |
24fb6b8e IR |
3601 | const struct perf_event *le = *(const struct perf_event **)l; |
3602 | const struct perf_event *re = *(const struct perf_event **)r; | |
6eef8a71 IR |
3603 | |
3604 | return le->group_index < re->group_index; | |
3605 | } | |
3606 | ||
3607 | static void swap_ptr(void *l, void *r) | |
3608 | { | |
3609 | void **lp = l, **rp = r; | |
3610 | ||
3611 | swap(*lp, *rp); | |
3612 | } | |
3613 | ||
3614 | static const struct min_heap_callbacks perf_min_heap = { | |
3615 | .elem_size = sizeof(struct perf_event *), | |
3616 | .less = perf_less_group_idx, | |
3617 | .swp = swap_ptr, | |
3618 | }; | |
3619 | ||
3620 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3621 | { | |
3622 | struct perf_event **itrs = heap->data; | |
3623 | ||
3624 | if (event) { | |
3625 | itrs[heap->nr] = event; | |
3626 | heap->nr++; | |
3627 | } | |
3628 | } | |
3629 | ||
836196be IR |
3630 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3631 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3632 | int (*func)(struct perf_event *, void *), |
3633 | void *data) | |
3634 | { | |
95ed6c70 IR |
3635 | #ifdef CONFIG_CGROUP_PERF |
3636 | struct cgroup_subsys_state *css = NULL; | |
3637 | #endif | |
6eef8a71 IR |
3638 | /* Space for per CPU and/or any CPU event iterators. */ |
3639 | struct perf_event *itrs[2]; | |
836196be IR |
3640 | struct min_heap event_heap; |
3641 | struct perf_event **evt; | |
1cac7b1a | 3642 | int ret; |
8e1a2031 | 3643 | |
836196be IR |
3644 | if (cpuctx) { |
3645 | event_heap = (struct min_heap){ | |
3646 | .data = cpuctx->heap, | |
3647 | .nr = 0, | |
3648 | .size = cpuctx->heap_size, | |
3649 | }; | |
c2283c93 IR |
3650 | |
3651 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3652 | |
3653 | #ifdef CONFIG_CGROUP_PERF | |
3654 | if (cpuctx->cgrp) | |
3655 | css = &cpuctx->cgrp->css; | |
3656 | #endif | |
836196be IR |
3657 | } else { |
3658 | event_heap = (struct min_heap){ | |
3659 | .data = itrs, | |
3660 | .nr = 0, | |
3661 | .size = ARRAY_SIZE(itrs), | |
3662 | }; | |
3663 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3664 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3665 | } |
3666 | evt = event_heap.data; | |
3667 | ||
95ed6c70 IR |
3668 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3669 | ||
3670 | #ifdef CONFIG_CGROUP_PERF | |
3671 | for (; css; css = css->parent) | |
3672 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3673 | #endif | |
1cac7b1a | 3674 | |
6eef8a71 | 3675 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3676 | |
6eef8a71 | 3677 | while (event_heap.nr) { |
1cac7b1a PZ |
3678 | ret = func(*evt, data); |
3679 | if (ret) | |
3680 | return ret; | |
3681 | ||
3682 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3683 | if (*evt) |
3684 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3685 | else | |
3686 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3687 | } |
0793a61d | 3688 | |
1cac7b1a PZ |
3689 | return 0; |
3690 | } | |
3691 | ||
ab6f824c | 3692 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3693 | { |
2c2366c7 PZ |
3694 | struct perf_event_context *ctx = event->ctx; |
3695 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3696 | int *can_add_hw = data; | |
ab6f824c | 3697 | |
1cac7b1a PZ |
3698 | if (event->state <= PERF_EVENT_STATE_OFF) |
3699 | return 0; | |
3700 | ||
3701 | if (!event_filter_match(event)) | |
3702 | return 0; | |
3703 | ||
2c2366c7 PZ |
3704 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3705 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3706 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3707 | } |
1cac7b1a | 3708 | |
ab6f824c | 3709 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
33238c50 PZ |
3710 | if (event->attr.pinned) { |
3711 | perf_cgroup_event_disable(event, ctx); | |
ab6f824c | 3712 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); |
33238c50 | 3713 | } |
1cac7b1a | 3714 | |
2c2366c7 PZ |
3715 | *can_add_hw = 0; |
3716 | ctx->rotate_necessary = 1; | |
2714c396 | 3717 | perf_mux_hrtimer_restart(cpuctx); |
3b6f9e5c | 3718 | } |
1cac7b1a PZ |
3719 | |
3720 | return 0; | |
5b0311e1 FW |
3721 | } |
3722 | ||
3723 | static void | |
1cac7b1a PZ |
3724 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3725 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3726 | { |
2c2366c7 | 3727 | int can_add_hw = 1; |
3b6f9e5c | 3728 | |
836196be IR |
3729 | if (ctx != &cpuctx->ctx) |
3730 | cpuctx = NULL; | |
3731 | ||
3732 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3733 | smp_processor_id(), |
2c2366c7 | 3734 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3735 | } |
8e1a2031 | 3736 | |
1cac7b1a PZ |
3737 | static void |
3738 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3739 | struct perf_cpu_context *cpuctx) | |
3740 | { | |
2c2366c7 | 3741 | int can_add_hw = 1; |
0793a61d | 3742 | |
836196be IR |
3743 | if (ctx != &cpuctx->ctx) |
3744 | cpuctx = NULL; | |
3745 | ||
3746 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3747 | smp_processor_id(), |
2c2366c7 | 3748 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3749 | } |
3750 | ||
3751 | static void | |
3752 | ctx_sched_in(struct perf_event_context *ctx, | |
3753 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3754 | enum event_type_t event_type, |
3755 | struct task_struct *task) | |
5b0311e1 | 3756 | { |
db24d33e | 3757 | int is_active = ctx->is_active; |
c994d613 PZ |
3758 | u64 now; |
3759 | ||
3760 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3761 | |
5b0311e1 | 3762 | if (likely(!ctx->nr_events)) |
facc4307 | 3763 | return; |
5b0311e1 | 3764 | |
3cbaa590 | 3765 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3766 | if (ctx->task) { |
3767 | if (!is_active) | |
3768 | cpuctx->task_ctx = ctx; | |
3769 | else | |
3770 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3771 | } | |
3772 | ||
3cbaa590 PZ |
3773 | is_active ^= ctx->is_active; /* changed bits */ |
3774 | ||
3775 | if (is_active & EVENT_TIME) { | |
3776 | /* start ctx time */ | |
3777 | now = perf_clock(); | |
3778 | ctx->timestamp = now; | |
3779 | perf_cgroup_set_timestamp(task, ctx); | |
3780 | } | |
3781 | ||
5b0311e1 FW |
3782 | /* |
3783 | * First go through the list and put on any pinned groups | |
3784 | * in order to give them the best chance of going on. | |
3785 | */ | |
3cbaa590 | 3786 | if (is_active & EVENT_PINNED) |
6e37738a | 3787 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3788 | |
3789 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3790 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3791 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3792 | } |
3793 | ||
329c0e01 | 3794 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3795 | enum event_type_t event_type, |
3796 | struct task_struct *task) | |
329c0e01 FW |
3797 | { |
3798 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3799 | ||
e5d1367f | 3800 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3801 | } |
3802 | ||
e5d1367f SE |
3803 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3804 | struct task_struct *task) | |
235c7fc7 | 3805 | { |
108b02cf | 3806 | struct perf_cpu_context *cpuctx; |
556cccad | 3807 | struct pmu *pmu = ctx->pmu; |
235c7fc7 | 3808 | |
108b02cf | 3809 | cpuctx = __get_cpu_context(ctx); |
556cccad KL |
3810 | if (cpuctx->task_ctx == ctx) { |
3811 | if (cpuctx->sched_cb_usage) | |
3812 | __perf_pmu_sched_task(cpuctx, true); | |
329c0e01 | 3813 | return; |
556cccad | 3814 | } |
329c0e01 | 3815 | |
facc4307 | 3816 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3817 | /* |
3818 | * We must check ctx->nr_events while holding ctx->lock, such | |
3819 | * that we serialize against perf_install_in_context(). | |
3820 | */ | |
3821 | if (!ctx->nr_events) | |
3822 | goto unlock; | |
3823 | ||
556cccad | 3824 | perf_pmu_disable(pmu); |
329c0e01 FW |
3825 | /* |
3826 | * We want to keep the following priority order: | |
3827 | * cpu pinned (that don't need to move), task pinned, | |
3828 | * cpu flexible, task flexible. | |
fe45bafb AS |
3829 | * |
3830 | * However, if task's ctx is not carrying any pinned | |
3831 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3832 | */ |
8e1a2031 | 3833 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3834 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3835 | perf_event_sched_in(cpuctx, ctx, task); |
556cccad KL |
3836 | |
3837 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3838 | pmu->sched_task(cpuctx->task_ctx, true); | |
3839 | ||
3840 | perf_pmu_enable(pmu); | |
fdccc3fb | 3841 | |
3842 | unlock: | |
facc4307 | 3843 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3844 | } |
3845 | ||
8dc85d54 PZ |
3846 | /* |
3847 | * Called from scheduler to add the events of the current task | |
3848 | * with interrupts disabled. | |
3849 | * | |
3850 | * We restore the event value and then enable it. | |
3851 | * | |
3852 | * This does not protect us against NMI, but enable() | |
3853 | * sets the enabled bit in the control field of event _before_ | |
3854 | * accessing the event control register. If a NMI hits, then it will | |
3855 | * keep the event running. | |
3856 | */ | |
ab0cce56 JO |
3857 | void __perf_event_task_sched_in(struct task_struct *prev, |
3858 | struct task_struct *task) | |
8dc85d54 PZ |
3859 | { |
3860 | struct perf_event_context *ctx; | |
3861 | int ctxn; | |
3862 | ||
7e41d177 PZ |
3863 | /* |
3864 | * If cgroup events exist on this CPU, then we need to check if we have | |
3865 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3866 | * | |
3867 | * Since cgroup events are CPU events, we must schedule these in before | |
3868 | * we schedule in the task events. | |
3869 | */ | |
3870 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3871 | perf_cgroup_sched_in(prev, task); | |
3872 | ||
8dc85d54 PZ |
3873 | for_each_task_context_nr(ctxn) { |
3874 | ctx = task->perf_event_ctxp[ctxn]; | |
3875 | if (likely(!ctx)) | |
3876 | continue; | |
3877 | ||
e5d1367f | 3878 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3879 | } |
d010b332 | 3880 | |
45ac1403 AH |
3881 | if (atomic_read(&nr_switch_events)) |
3882 | perf_event_switch(task, prev, true); | |
f008790a KL |
3883 | |
3884 | if (__this_cpu_read(perf_sched_cb_usages)) | |
3885 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3886 | } |
3887 | ||
abd50713 PZ |
3888 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3889 | { | |
3890 | u64 frequency = event->attr.sample_freq; | |
3891 | u64 sec = NSEC_PER_SEC; | |
3892 | u64 divisor, dividend; | |
3893 | ||
3894 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3895 | ||
3896 | count_fls = fls64(count); | |
3897 | nsec_fls = fls64(nsec); | |
3898 | frequency_fls = fls64(frequency); | |
3899 | sec_fls = 30; | |
3900 | ||
3901 | /* | |
3902 | * We got @count in @nsec, with a target of sample_freq HZ | |
3903 | * the target period becomes: | |
3904 | * | |
3905 | * @count * 10^9 | |
3906 | * period = ------------------- | |
3907 | * @nsec * sample_freq | |
3908 | * | |
3909 | */ | |
3910 | ||
3911 | /* | |
3912 | * Reduce accuracy by one bit such that @a and @b converge | |
3913 | * to a similar magnitude. | |
3914 | */ | |
fe4b04fa | 3915 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3916 | do { \ |
3917 | if (a##_fls > b##_fls) { \ | |
3918 | a >>= 1; \ | |
3919 | a##_fls--; \ | |
3920 | } else { \ | |
3921 | b >>= 1; \ | |
3922 | b##_fls--; \ | |
3923 | } \ | |
3924 | } while (0) | |
3925 | ||
3926 | /* | |
3927 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3928 | * the other, so that finally we can do a u64/u64 division. | |
3929 | */ | |
3930 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3931 | REDUCE_FLS(nsec, frequency); | |
3932 | REDUCE_FLS(sec, count); | |
3933 | } | |
3934 | ||
3935 | if (count_fls + sec_fls > 64) { | |
3936 | divisor = nsec * frequency; | |
3937 | ||
3938 | while (count_fls + sec_fls > 64) { | |
3939 | REDUCE_FLS(count, sec); | |
3940 | divisor >>= 1; | |
3941 | } | |
3942 | ||
3943 | dividend = count * sec; | |
3944 | } else { | |
3945 | dividend = count * sec; | |
3946 | ||
3947 | while (nsec_fls + frequency_fls > 64) { | |
3948 | REDUCE_FLS(nsec, frequency); | |
3949 | dividend >>= 1; | |
3950 | } | |
3951 | ||
3952 | divisor = nsec * frequency; | |
3953 | } | |
3954 | ||
f6ab91ad PZ |
3955 | if (!divisor) |
3956 | return dividend; | |
3957 | ||
abd50713 PZ |
3958 | return div64_u64(dividend, divisor); |
3959 | } | |
3960 | ||
e050e3f0 SE |
3961 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3962 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3963 | ||
f39d47ff | 3964 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3965 | { |
cdd6c482 | 3966 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3967 | s64 period, sample_period; |
bd2b5b12 PZ |
3968 | s64 delta; |
3969 | ||
abd50713 | 3970 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3971 | |
3972 | delta = (s64)(period - hwc->sample_period); | |
3973 | delta = (delta + 7) / 8; /* low pass filter */ | |
3974 | ||
3975 | sample_period = hwc->sample_period + delta; | |
3976 | ||
3977 | if (!sample_period) | |
3978 | sample_period = 1; | |
3979 | ||
bd2b5b12 | 3980 | hwc->sample_period = sample_period; |
abd50713 | 3981 | |
e7850595 | 3982 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3983 | if (disable) |
3984 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3985 | ||
e7850595 | 3986 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3987 | |
3988 | if (disable) | |
3989 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3990 | } |
bd2b5b12 PZ |
3991 | } |
3992 | ||
e050e3f0 SE |
3993 | /* |
3994 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3995 | * events. At the same time, make sure, having freq events does not change | |
3996 | * the rate of unthrottling as that would introduce bias. | |
3997 | */ | |
3998 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3999 | int needs_unthr) | |
60db5e09 | 4000 | { |
cdd6c482 IM |
4001 | struct perf_event *event; |
4002 | struct hw_perf_event *hwc; | |
e050e3f0 | 4003 | u64 now, period = TICK_NSEC; |
abd50713 | 4004 | s64 delta; |
60db5e09 | 4005 | |
e050e3f0 SE |
4006 | /* |
4007 | * only need to iterate over all events iff: | |
4008 | * - context have events in frequency mode (needs freq adjust) | |
4009 | * - there are events to unthrottle on this cpu | |
4010 | */ | |
4011 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
4012 | return; |
4013 | ||
e050e3f0 | 4014 | raw_spin_lock(&ctx->lock); |
f39d47ff | 4015 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 4016 | |
03541f8b | 4017 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 4018 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
4019 | continue; |
4020 | ||
5632ab12 | 4021 | if (!event_filter_match(event)) |
5d27c23d PZ |
4022 | continue; |
4023 | ||
44377277 AS |
4024 | perf_pmu_disable(event->pmu); |
4025 | ||
cdd6c482 | 4026 | hwc = &event->hw; |
6a24ed6c | 4027 | |
ae23bff1 | 4028 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 4029 | hwc->interrupts = 0; |
cdd6c482 | 4030 | perf_log_throttle(event, 1); |
a4eaf7f1 | 4031 | event->pmu->start(event, 0); |
a78ac325 PZ |
4032 | } |
4033 | ||
cdd6c482 | 4034 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 4035 | goto next; |
60db5e09 | 4036 | |
e050e3f0 SE |
4037 | /* |
4038 | * stop the event and update event->count | |
4039 | */ | |
4040 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4041 | ||
e7850595 | 4042 | now = local64_read(&event->count); |
abd50713 PZ |
4043 | delta = now - hwc->freq_count_stamp; |
4044 | hwc->freq_count_stamp = now; | |
60db5e09 | 4045 | |
e050e3f0 SE |
4046 | /* |
4047 | * restart the event | |
4048 | * reload only if value has changed | |
f39d47ff SE |
4049 | * we have stopped the event so tell that |
4050 | * to perf_adjust_period() to avoid stopping it | |
4051 | * twice. | |
e050e3f0 | 4052 | */ |
abd50713 | 4053 | if (delta > 0) |
f39d47ff | 4054 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
4055 | |
4056 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
4057 | next: |
4058 | perf_pmu_enable(event->pmu); | |
60db5e09 | 4059 | } |
e050e3f0 | 4060 | |
f39d47ff | 4061 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 4062 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
4063 | } |
4064 | ||
235c7fc7 | 4065 | /* |
8703a7cf | 4066 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 4067 | */ |
8703a7cf | 4068 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 4069 | { |
dddd3379 TG |
4070 | /* |
4071 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
4072 | * disabled by the inheritance code. | |
4073 | */ | |
8703a7cf PZ |
4074 | if (ctx->rotate_disable) |
4075 | return; | |
8e1a2031 | 4076 | |
8703a7cf PZ |
4077 | perf_event_groups_delete(&ctx->flexible_groups, event); |
4078 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
4079 | } |
4080 | ||
7fa343b7 | 4081 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 4082 | static inline struct perf_event * |
7fa343b7 | 4083 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 4084 | { |
7fa343b7 SL |
4085 | struct perf_event *event; |
4086 | ||
4087 | /* pick the first active flexible event */ | |
4088 | event = list_first_entry_or_null(&ctx->flexible_active, | |
4089 | struct perf_event, active_list); | |
4090 | ||
4091 | /* if no active flexible event, pick the first event */ | |
4092 | if (!event) { | |
4093 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
4094 | typeof(*event), group_node); | |
4095 | } | |
4096 | ||
90c91dfb PZ |
4097 | /* |
4098 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
4099 | * finds there are unschedulable events, it will set it again. | |
4100 | */ | |
4101 | ctx->rotate_necessary = 0; | |
4102 | ||
7fa343b7 | 4103 | return event; |
8d5bce0c PZ |
4104 | } |
4105 | ||
4106 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4107 | { | |
4108 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4109 | struct perf_event_context *task_ctx = NULL; |
4110 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4111 | |
4112 | /* | |
4113 | * Since we run this from IRQ context, nobody can install new | |
4114 | * events, thus the event count values are stable. | |
4115 | */ | |
7fc23a53 | 4116 | |
fd7d5517 IR |
4117 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4118 | task_ctx = cpuctx->task_ctx; | |
4119 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4120 | |
8d5bce0c PZ |
4121 | if (!(cpu_rotate || task_rotate)) |
4122 | return false; | |
0f5a2601 | 4123 | |
facc4307 | 4124 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4125 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4126 | |
8d5bce0c | 4127 | if (task_rotate) |
7fa343b7 | 4128 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4129 | if (cpu_rotate) |
7fa343b7 | 4130 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4131 | |
8d5bce0c PZ |
4132 | /* |
4133 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4134 | * and then, if needed CPU flexible. | |
4135 | */ | |
fd7d5517 IR |
4136 | if (task_event || (task_ctx && cpu_event)) |
4137 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4138 | if (cpu_event) |
4139 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4140 | |
8d5bce0c | 4141 | if (task_event) |
fd7d5517 | 4142 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4143 | if (cpu_event) |
4144 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4145 | |
fd7d5517 | 4146 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4147 | |
0f5a2601 PZ |
4148 | perf_pmu_enable(cpuctx->ctx.pmu); |
4149 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4150 | |
8d5bce0c | 4151 | return true; |
e9d2b064 PZ |
4152 | } |
4153 | ||
4154 | void perf_event_task_tick(void) | |
4155 | { | |
2fde4f94 MR |
4156 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4157 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4158 | int throttled; |
b5ab4cd5 | 4159 | |
16444645 | 4160 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4161 | |
e050e3f0 SE |
4162 | __this_cpu_inc(perf_throttled_seq); |
4163 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4164 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4165 | |
2fde4f94 | 4166 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4167 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4168 | } |
4169 | ||
889ff015 FW |
4170 | static int event_enable_on_exec(struct perf_event *event, |
4171 | struct perf_event_context *ctx) | |
4172 | { | |
4173 | if (!event->attr.enable_on_exec) | |
4174 | return 0; | |
4175 | ||
4176 | event->attr.enable_on_exec = 0; | |
4177 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4178 | return 0; | |
4179 | ||
0d3d73aa | 4180 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4181 | |
4182 | return 1; | |
4183 | } | |
4184 | ||
57e7986e | 4185 | /* |
cdd6c482 | 4186 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4187 | * This expects task == current. |
4188 | */ | |
c1274499 | 4189 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4190 | { |
c1274499 | 4191 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4192 | enum event_type_t event_type = 0; |
3e349507 | 4193 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4194 | struct perf_event *event; |
57e7986e PM |
4195 | unsigned long flags; |
4196 | int enabled = 0; | |
4197 | ||
4198 | local_irq_save(flags); | |
c1274499 | 4199 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4200 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4201 | goto out; |
4202 | ||
3e349507 PZ |
4203 | cpuctx = __get_cpu_context(ctx); |
4204 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4205 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4206 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4207 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4208 | event_type |= get_event_type(event); |
4209 | } | |
57e7986e PM |
4210 | |
4211 | /* | |
3e349507 | 4212 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4213 | */ |
3e349507 | 4214 | if (enabled) { |
211de6eb | 4215 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4216 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4217 | } else { |
4218 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4219 | } |
4220 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4221 | |
9ed6060d | 4222 | out: |
57e7986e | 4223 | local_irq_restore(flags); |
211de6eb PZ |
4224 | |
4225 | if (clone_ctx) | |
4226 | put_ctx(clone_ctx); | |
57e7986e PM |
4227 | } |
4228 | ||
0492d4c5 PZ |
4229 | struct perf_read_data { |
4230 | struct perf_event *event; | |
4231 | bool group; | |
7d88962e | 4232 | int ret; |
0492d4c5 PZ |
4233 | }; |
4234 | ||
451d24d1 | 4235 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4236 | { |
d6a2f903 DCC |
4237 | u16 local_pkg, event_pkg; |
4238 | ||
4239 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4240 | int local_cpu = smp_processor_id(); |
4241 | ||
4242 | event_pkg = topology_physical_package_id(event_cpu); | |
4243 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4244 | |
4245 | if (event_pkg == local_pkg) | |
4246 | return local_cpu; | |
4247 | } | |
4248 | ||
4249 | return event_cpu; | |
4250 | } | |
4251 | ||
0793a61d | 4252 | /* |
cdd6c482 | 4253 | * Cross CPU call to read the hardware event |
0793a61d | 4254 | */ |
cdd6c482 | 4255 | static void __perf_event_read(void *info) |
0793a61d | 4256 | { |
0492d4c5 PZ |
4257 | struct perf_read_data *data = info; |
4258 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4259 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4260 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4261 | struct pmu *pmu = event->pmu; |
621a01ea | 4262 | |
e1ac3614 PM |
4263 | /* |
4264 | * If this is a task context, we need to check whether it is | |
4265 | * the current task context of this cpu. If not it has been | |
4266 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4267 | * event->count would have been updated to a recent sample |
4268 | * when the event was scheduled out. | |
e1ac3614 PM |
4269 | */ |
4270 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4271 | return; | |
4272 | ||
e625cce1 | 4273 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4274 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4275 | update_context_time(ctx); |
e5d1367f SE |
4276 | update_cgrp_time_from_event(event); |
4277 | } | |
0492d4c5 | 4278 | |
0d3d73aa PZ |
4279 | perf_event_update_time(event); |
4280 | if (data->group) | |
4281 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4282 | |
4a00c16e SB |
4283 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4284 | goto unlock; | |
0492d4c5 | 4285 | |
4a00c16e SB |
4286 | if (!data->group) { |
4287 | pmu->read(event); | |
4288 | data->ret = 0; | |
0492d4c5 | 4289 | goto unlock; |
4a00c16e SB |
4290 | } |
4291 | ||
4292 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4293 | ||
4294 | pmu->read(event); | |
0492d4c5 | 4295 | |
edb39592 | 4296 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4297 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4298 | /* | |
4299 | * Use sibling's PMU rather than @event's since | |
4300 | * sibling could be on different (eg: software) PMU. | |
4301 | */ | |
0492d4c5 | 4302 | sub->pmu->read(sub); |
4a00c16e | 4303 | } |
0492d4c5 | 4304 | } |
4a00c16e SB |
4305 | |
4306 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4307 | |
4308 | unlock: | |
e625cce1 | 4309 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4310 | } |
4311 | ||
b5e58793 PZ |
4312 | static inline u64 perf_event_count(struct perf_event *event) |
4313 | { | |
c39a0e2c | 4314 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4315 | } |
4316 | ||
ffe8690c KX |
4317 | /* |
4318 | * NMI-safe method to read a local event, that is an event that | |
4319 | * is: | |
4320 | * - either for the current task, or for this CPU | |
4321 | * - does not have inherit set, for inherited task events | |
4322 | * will not be local and we cannot read them atomically | |
4323 | * - must not have a pmu::count method | |
4324 | */ | |
7d9285e8 YS |
4325 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4326 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4327 | { |
4328 | unsigned long flags; | |
f91840a3 | 4329 | int ret = 0; |
ffe8690c KX |
4330 | |
4331 | /* | |
4332 | * Disabling interrupts avoids all counter scheduling (context | |
4333 | * switches, timer based rotation and IPIs). | |
4334 | */ | |
4335 | local_irq_save(flags); | |
4336 | ||
ffe8690c KX |
4337 | /* |
4338 | * It must not be an event with inherit set, we cannot read | |
4339 | * all child counters from atomic context. | |
4340 | */ | |
f91840a3 AS |
4341 | if (event->attr.inherit) { |
4342 | ret = -EOPNOTSUPP; | |
4343 | goto out; | |
4344 | } | |
ffe8690c | 4345 | |
f91840a3 AS |
4346 | /* If this is a per-task event, it must be for current */ |
4347 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4348 | event->hw.target != current) { | |
4349 | ret = -EINVAL; | |
4350 | goto out; | |
4351 | } | |
4352 | ||
4353 | /* If this is a per-CPU event, it must be for this CPU */ | |
4354 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4355 | event->cpu != smp_processor_id()) { | |
4356 | ret = -EINVAL; | |
4357 | goto out; | |
4358 | } | |
ffe8690c | 4359 | |
befb1b3c RC |
4360 | /* If this is a pinned event it must be running on this CPU */ |
4361 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4362 | ret = -EBUSY; | |
4363 | goto out; | |
4364 | } | |
4365 | ||
ffe8690c KX |
4366 | /* |
4367 | * If the event is currently on this CPU, its either a per-task event, | |
4368 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4369 | * oncpu == -1). | |
4370 | */ | |
4371 | if (event->oncpu == smp_processor_id()) | |
4372 | event->pmu->read(event); | |
4373 | ||
f91840a3 | 4374 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4375 | if (enabled || running) { |
4376 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4377 | u64 __enabled, __running; | |
4378 | ||
4379 | __perf_update_times(event, now, &__enabled, &__running); | |
4380 | if (enabled) | |
4381 | *enabled = __enabled; | |
4382 | if (running) | |
4383 | *running = __running; | |
4384 | } | |
f91840a3 | 4385 | out: |
ffe8690c KX |
4386 | local_irq_restore(flags); |
4387 | ||
f91840a3 | 4388 | return ret; |
ffe8690c KX |
4389 | } |
4390 | ||
7d88962e | 4391 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4392 | { |
0c1cbc18 | 4393 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4394 | int event_cpu, ret = 0; |
7d88962e | 4395 | |
0793a61d | 4396 | /* |
cdd6c482 IM |
4397 | * If event is enabled and currently active on a CPU, update the |
4398 | * value in the event structure: | |
0793a61d | 4399 | */ |
0c1cbc18 PZ |
4400 | again: |
4401 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4402 | struct perf_read_data data; | |
4403 | ||
4404 | /* | |
4405 | * Orders the ->state and ->oncpu loads such that if we see | |
4406 | * ACTIVE we must also see the right ->oncpu. | |
4407 | * | |
4408 | * Matches the smp_wmb() from event_sched_in(). | |
4409 | */ | |
4410 | smp_rmb(); | |
d6a2f903 | 4411 | |
451d24d1 PZ |
4412 | event_cpu = READ_ONCE(event->oncpu); |
4413 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4414 | return 0; | |
4415 | ||
0c1cbc18 PZ |
4416 | data = (struct perf_read_data){ |
4417 | .event = event, | |
4418 | .group = group, | |
4419 | .ret = 0, | |
4420 | }; | |
4421 | ||
451d24d1 PZ |
4422 | preempt_disable(); |
4423 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4424 | |
58763148 PZ |
4425 | /* |
4426 | * Purposely ignore the smp_call_function_single() return | |
4427 | * value. | |
4428 | * | |
451d24d1 | 4429 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4430 | * scheduled out and that will have updated the event count. |
4431 | * | |
4432 | * Therefore, either way, we'll have an up-to-date event count | |
4433 | * after this. | |
4434 | */ | |
451d24d1 PZ |
4435 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4436 | preempt_enable(); | |
58763148 | 4437 | ret = data.ret; |
0c1cbc18 PZ |
4438 | |
4439 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4440 | struct perf_event_context *ctx = event->ctx; |
4441 | unsigned long flags; | |
4442 | ||
e625cce1 | 4443 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4444 | state = event->state; |
4445 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4446 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4447 | goto again; | |
4448 | } | |
4449 | ||
c530ccd9 | 4450 | /* |
0c1cbc18 PZ |
4451 | * May read while context is not active (e.g., thread is |
4452 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4453 | */ |
0c1cbc18 | 4454 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4455 | update_context_time(ctx); |
e5d1367f SE |
4456 | update_cgrp_time_from_event(event); |
4457 | } | |
0c1cbc18 | 4458 | |
0d3d73aa | 4459 | perf_event_update_time(event); |
0492d4c5 | 4460 | if (group) |
0d3d73aa | 4461 | perf_event_update_sibling_time(event); |
e625cce1 | 4462 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4463 | } |
7d88962e SB |
4464 | |
4465 | return ret; | |
0793a61d TG |
4466 | } |
4467 | ||
a63eaf34 | 4468 | /* |
cdd6c482 | 4469 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4470 | */ |
eb184479 | 4471 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4472 | { |
e625cce1 | 4473 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4474 | mutex_init(&ctx->mutex); |
2fde4f94 | 4475 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4476 | perf_event_groups_init(&ctx->pinned_groups); |
4477 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4478 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4479 | INIT_LIST_HEAD(&ctx->pinned_active); |
4480 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4481 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4482 | } |
4483 | ||
4484 | static struct perf_event_context * | |
4485 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4486 | { | |
4487 | struct perf_event_context *ctx; | |
4488 | ||
4489 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4490 | if (!ctx) | |
4491 | return NULL; | |
4492 | ||
4493 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4494 | if (task) |
4495 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4496 | ctx->pmu = pmu; |
4497 | ||
4498 | return ctx; | |
a63eaf34 PM |
4499 | } |
4500 | ||
2ebd4ffb MH |
4501 | static struct task_struct * |
4502 | find_lively_task_by_vpid(pid_t vpid) | |
4503 | { | |
4504 | struct task_struct *task; | |
0793a61d TG |
4505 | |
4506 | rcu_read_lock(); | |
2ebd4ffb | 4507 | if (!vpid) |
0793a61d TG |
4508 | task = current; |
4509 | else | |
2ebd4ffb | 4510 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4511 | if (task) |
4512 | get_task_struct(task); | |
4513 | rcu_read_unlock(); | |
4514 | ||
4515 | if (!task) | |
4516 | return ERR_PTR(-ESRCH); | |
4517 | ||
2ebd4ffb | 4518 | return task; |
2ebd4ffb MH |
4519 | } |
4520 | ||
fe4b04fa PZ |
4521 | /* |
4522 | * Returns a matching context with refcount and pincount. | |
4523 | */ | |
108b02cf | 4524 | static struct perf_event_context * |
4af57ef2 YZ |
4525 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4526 | struct perf_event *event) | |
0793a61d | 4527 | { |
211de6eb | 4528 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4529 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4530 | void *task_ctx_data = NULL; |
25346b93 | 4531 | unsigned long flags; |
8dc85d54 | 4532 | int ctxn, err; |
4af57ef2 | 4533 | int cpu = event->cpu; |
0793a61d | 4534 | |
22a4ec72 | 4535 | if (!task) { |
cdd6c482 | 4536 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4537 | err = perf_allow_cpu(&event->attr); |
4538 | if (err) | |
4539 | return ERR_PTR(err); | |
0793a61d | 4540 | |
108b02cf | 4541 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4542 | ctx = &cpuctx->ctx; |
c93f7669 | 4543 | get_ctx(ctx); |
fe4b04fa | 4544 | ++ctx->pin_count; |
0793a61d | 4545 | |
0793a61d TG |
4546 | return ctx; |
4547 | } | |
4548 | ||
8dc85d54 PZ |
4549 | err = -EINVAL; |
4550 | ctxn = pmu->task_ctx_nr; | |
4551 | if (ctxn < 0) | |
4552 | goto errout; | |
4553 | ||
4af57ef2 | 4554 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
ff9ff926 | 4555 | task_ctx_data = alloc_task_ctx_data(pmu); |
4af57ef2 YZ |
4556 | if (!task_ctx_data) { |
4557 | err = -ENOMEM; | |
4558 | goto errout; | |
4559 | } | |
4560 | } | |
4561 | ||
9ed6060d | 4562 | retry: |
8dc85d54 | 4563 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4564 | if (ctx) { |
211de6eb | 4565 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4566 | ++ctx->pin_count; |
4af57ef2 YZ |
4567 | |
4568 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4569 | ctx->task_ctx_data = task_ctx_data; | |
4570 | task_ctx_data = NULL; | |
4571 | } | |
e625cce1 | 4572 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4573 | |
4574 | if (clone_ctx) | |
4575 | put_ctx(clone_ctx); | |
9137fb28 | 4576 | } else { |
eb184479 | 4577 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4578 | err = -ENOMEM; |
4579 | if (!ctx) | |
4580 | goto errout; | |
eb184479 | 4581 | |
4af57ef2 YZ |
4582 | if (task_ctx_data) { |
4583 | ctx->task_ctx_data = task_ctx_data; | |
4584 | task_ctx_data = NULL; | |
4585 | } | |
4586 | ||
dbe08d82 ON |
4587 | err = 0; |
4588 | mutex_lock(&task->perf_event_mutex); | |
4589 | /* | |
4590 | * If it has already passed perf_event_exit_task(). | |
4591 | * we must see PF_EXITING, it takes this mutex too. | |
4592 | */ | |
4593 | if (task->flags & PF_EXITING) | |
4594 | err = -ESRCH; | |
4595 | else if (task->perf_event_ctxp[ctxn]) | |
4596 | err = -EAGAIN; | |
fe4b04fa | 4597 | else { |
9137fb28 | 4598 | get_ctx(ctx); |
fe4b04fa | 4599 | ++ctx->pin_count; |
dbe08d82 | 4600 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4601 | } |
dbe08d82 ON |
4602 | mutex_unlock(&task->perf_event_mutex); |
4603 | ||
4604 | if (unlikely(err)) { | |
9137fb28 | 4605 | put_ctx(ctx); |
dbe08d82 ON |
4606 | |
4607 | if (err == -EAGAIN) | |
4608 | goto retry; | |
4609 | goto errout; | |
a63eaf34 PM |
4610 | } |
4611 | } | |
4612 | ||
ff9ff926 | 4613 | free_task_ctx_data(pmu, task_ctx_data); |
0793a61d | 4614 | return ctx; |
c93f7669 | 4615 | |
9ed6060d | 4616 | errout: |
ff9ff926 | 4617 | free_task_ctx_data(pmu, task_ctx_data); |
c93f7669 | 4618 | return ERR_PTR(err); |
0793a61d TG |
4619 | } |
4620 | ||
6fb2915d | 4621 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4622 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4623 | |
cdd6c482 | 4624 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4625 | { |
cdd6c482 | 4626 | struct perf_event *event; |
592903cd | 4627 | |
cdd6c482 IM |
4628 | event = container_of(head, struct perf_event, rcu_head); |
4629 | if (event->ns) | |
4630 | put_pid_ns(event->ns); | |
6fb2915d | 4631 | perf_event_free_filter(event); |
cdd6c482 | 4632 | kfree(event); |
592903cd PZ |
4633 | } |
4634 | ||
b69cf536 | 4635 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4636 | struct perf_buffer *rb); |
925d519a | 4637 | |
f2fb6bef KL |
4638 | static void detach_sb_event(struct perf_event *event) |
4639 | { | |
4640 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4641 | ||
4642 | raw_spin_lock(&pel->lock); | |
4643 | list_del_rcu(&event->sb_list); | |
4644 | raw_spin_unlock(&pel->lock); | |
4645 | } | |
4646 | ||
a4f144eb | 4647 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4648 | { |
a4f144eb DCC |
4649 | struct perf_event_attr *attr = &event->attr; |
4650 | ||
f2fb6bef | 4651 | if (event->parent) |
a4f144eb | 4652 | return false; |
f2fb6bef KL |
4653 | |
4654 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4655 | return false; |
f2fb6bef | 4656 | |
a4f144eb DCC |
4657 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4658 | attr->comm || attr->comm_exec || | |
76193a94 | 4659 | attr->task || attr->ksymbol || |
e17d43b9 | 4660 | attr->context_switch || attr->text_poke || |
21038f2b | 4661 | attr->bpf_event) |
a4f144eb DCC |
4662 | return true; |
4663 | return false; | |
4664 | } | |
4665 | ||
4666 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4667 | { | |
4668 | if (is_sb_event(event)) | |
4669 | detach_sb_event(event); | |
f2fb6bef KL |
4670 | } |
4671 | ||
4beb31f3 | 4672 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4673 | { |
4beb31f3 FW |
4674 | if (event->parent) |
4675 | return; | |
4676 | ||
4beb31f3 FW |
4677 | if (is_cgroup_event(event)) |
4678 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4679 | } | |
925d519a | 4680 | |
555e0c1e FW |
4681 | #ifdef CONFIG_NO_HZ_FULL |
4682 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4683 | #endif | |
4684 | ||
4685 | static void unaccount_freq_event_nohz(void) | |
4686 | { | |
4687 | #ifdef CONFIG_NO_HZ_FULL | |
4688 | spin_lock(&nr_freq_lock); | |
4689 | if (atomic_dec_and_test(&nr_freq_events)) | |
4690 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4691 | spin_unlock(&nr_freq_lock); | |
4692 | #endif | |
4693 | } | |
4694 | ||
4695 | static void unaccount_freq_event(void) | |
4696 | { | |
4697 | if (tick_nohz_full_enabled()) | |
4698 | unaccount_freq_event_nohz(); | |
4699 | else | |
4700 | atomic_dec(&nr_freq_events); | |
4701 | } | |
4702 | ||
4beb31f3 FW |
4703 | static void unaccount_event(struct perf_event *event) |
4704 | { | |
25432ae9 PZ |
4705 | bool dec = false; |
4706 | ||
4beb31f3 FW |
4707 | if (event->parent) |
4708 | return; | |
4709 | ||
f008790a | 4710 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 4711 | dec = true; |
4beb31f3 FW |
4712 | if (event->attr.mmap || event->attr.mmap_data) |
4713 | atomic_dec(&nr_mmap_events); | |
4714 | if (event->attr.comm) | |
4715 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4716 | if (event->attr.namespaces) |
4717 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4718 | if (event->attr.cgroup) |
4719 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4720 | if (event->attr.task) |
4721 | atomic_dec(&nr_task_events); | |
948b26b6 | 4722 | if (event->attr.freq) |
555e0c1e | 4723 | unaccount_freq_event(); |
45ac1403 | 4724 | if (event->attr.context_switch) { |
25432ae9 | 4725 | dec = true; |
45ac1403 AH |
4726 | atomic_dec(&nr_switch_events); |
4727 | } | |
4beb31f3 | 4728 | if (is_cgroup_event(event)) |
25432ae9 | 4729 | dec = true; |
4beb31f3 | 4730 | if (has_branch_stack(event)) |
25432ae9 | 4731 | dec = true; |
76193a94 SL |
4732 | if (event->attr.ksymbol) |
4733 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4734 | if (event->attr.bpf_event) |
4735 | atomic_dec(&nr_bpf_events); | |
e17d43b9 AH |
4736 | if (event->attr.text_poke) |
4737 | atomic_dec(&nr_text_poke_events); | |
25432ae9 | 4738 | |
9107c89e PZ |
4739 | if (dec) { |
4740 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4741 | schedule_delayed_work(&perf_sched_work, HZ); | |
4742 | } | |
4beb31f3 FW |
4743 | |
4744 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4745 | |
4746 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4747 | } |
925d519a | 4748 | |
9107c89e PZ |
4749 | static void perf_sched_delayed(struct work_struct *work) |
4750 | { | |
4751 | mutex_lock(&perf_sched_mutex); | |
4752 | if (atomic_dec_and_test(&perf_sched_count)) | |
4753 | static_branch_disable(&perf_sched_events); | |
4754 | mutex_unlock(&perf_sched_mutex); | |
4755 | } | |
4756 | ||
bed5b25a AS |
4757 | /* |
4758 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4759 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4760 | * at a time, so we disallow creating events that might conflict, namely: | |
4761 | * | |
4762 | * 1) cpu-wide events in the presence of per-task events, | |
4763 | * 2) per-task events in the presence of cpu-wide events, | |
4764 | * 3) two matching events on the same context. | |
4765 | * | |
4766 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4767 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4768 | */ |
4769 | static int exclusive_event_init(struct perf_event *event) | |
4770 | { | |
4771 | struct pmu *pmu = event->pmu; | |
4772 | ||
8a58ddae | 4773 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4774 | return 0; |
4775 | ||
4776 | /* | |
4777 | * Prevent co-existence of per-task and cpu-wide events on the | |
4778 | * same exclusive pmu. | |
4779 | * | |
4780 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4781 | * events on this "exclusive" pmu, positive means there are | |
4782 | * per-task events. | |
4783 | * | |
4784 | * Since this is called in perf_event_alloc() path, event::ctx | |
4785 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4786 | * to mean "per-task event", because unlike other attach states it | |
4787 | * never gets cleared. | |
4788 | */ | |
4789 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4790 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4791 | return -EBUSY; | |
4792 | } else { | |
4793 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4794 | return -EBUSY; | |
4795 | } | |
4796 | ||
4797 | return 0; | |
4798 | } | |
4799 | ||
4800 | static void exclusive_event_destroy(struct perf_event *event) | |
4801 | { | |
4802 | struct pmu *pmu = event->pmu; | |
4803 | ||
8a58ddae | 4804 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4805 | return; |
4806 | ||
4807 | /* see comment in exclusive_event_init() */ | |
4808 | if (event->attach_state & PERF_ATTACH_TASK) | |
4809 | atomic_dec(&pmu->exclusive_cnt); | |
4810 | else | |
4811 | atomic_inc(&pmu->exclusive_cnt); | |
4812 | } | |
4813 | ||
4814 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4815 | { | |
3bf6215a | 4816 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4817 | (e1->cpu == e2->cpu || |
4818 | e1->cpu == -1 || | |
4819 | e2->cpu == -1)) | |
4820 | return true; | |
4821 | return false; | |
4822 | } | |
4823 | ||
bed5b25a AS |
4824 | static bool exclusive_event_installable(struct perf_event *event, |
4825 | struct perf_event_context *ctx) | |
4826 | { | |
4827 | struct perf_event *iter_event; | |
4828 | struct pmu *pmu = event->pmu; | |
4829 | ||
8a58ddae AS |
4830 | lockdep_assert_held(&ctx->mutex); |
4831 | ||
4832 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4833 | return true; |
4834 | ||
4835 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4836 | if (exclusive_event_match(iter_event, event)) | |
4837 | return false; | |
4838 | } | |
4839 | ||
4840 | return true; | |
4841 | } | |
4842 | ||
375637bc AS |
4843 | static void perf_addr_filters_splice(struct perf_event *event, |
4844 | struct list_head *head); | |
4845 | ||
683ede43 | 4846 | static void _free_event(struct perf_event *event) |
f1600952 | 4847 | { |
e360adbe | 4848 | irq_work_sync(&event->pending); |
925d519a | 4849 | |
4beb31f3 | 4850 | unaccount_event(event); |
9ee318a7 | 4851 | |
da97e184 JFG |
4852 | security_perf_event_free(event); |
4853 | ||
76369139 | 4854 | if (event->rb) { |
9bb5d40c PZ |
4855 | /* |
4856 | * Can happen when we close an event with re-directed output. | |
4857 | * | |
4858 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4859 | * over us; possibly making our ring_buffer_put() the last. | |
4860 | */ | |
4861 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4862 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4863 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4864 | } |
4865 | ||
e5d1367f SE |
4866 | if (is_cgroup_event(event)) |
4867 | perf_detach_cgroup(event); | |
4868 | ||
a0733e69 PZ |
4869 | if (!event->parent) { |
4870 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4871 | put_callchain_buffers(); | |
4872 | } | |
4873 | ||
4874 | perf_event_free_bpf_prog(event); | |
375637bc | 4875 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4876 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4877 | |
4878 | if (event->destroy) | |
4879 | event->destroy(event); | |
4880 | ||
1cf8dfe8 PZ |
4881 | /* |
4882 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4883 | * hw.target. | |
4884 | */ | |
621b6d2e PB |
4885 | if (event->hw.target) |
4886 | put_task_struct(event->hw.target); | |
4887 | ||
1cf8dfe8 PZ |
4888 | /* |
4889 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4890 | * all task references must be cleaned up. | |
4891 | */ | |
4892 | if (event->ctx) | |
4893 | put_ctx(event->ctx); | |
4894 | ||
62a92c8f AS |
4895 | exclusive_event_destroy(event); |
4896 | module_put(event->pmu->module); | |
a0733e69 PZ |
4897 | |
4898 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4899 | } |
4900 | ||
683ede43 PZ |
4901 | /* |
4902 | * Used to free events which have a known refcount of 1, such as in error paths | |
4903 | * where the event isn't exposed yet and inherited events. | |
4904 | */ | |
4905 | static void free_event(struct perf_event *event) | |
0793a61d | 4906 | { |
683ede43 PZ |
4907 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4908 | "unexpected event refcount: %ld; ptr=%p\n", | |
4909 | atomic_long_read(&event->refcount), event)) { | |
4910 | /* leak to avoid use-after-free */ | |
4911 | return; | |
4912 | } | |
0793a61d | 4913 | |
683ede43 | 4914 | _free_event(event); |
0793a61d TG |
4915 | } |
4916 | ||
a66a3052 | 4917 | /* |
f8697762 | 4918 | * Remove user event from the owner task. |
a66a3052 | 4919 | */ |
f8697762 | 4920 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4921 | { |
8882135b | 4922 | struct task_struct *owner; |
fb0459d7 | 4923 | |
8882135b | 4924 | rcu_read_lock(); |
8882135b | 4925 | /* |
f47c02c0 PZ |
4926 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4927 | * observe !owner it means the list deletion is complete and we can | |
4928 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4929 | * owner->perf_event_mutex. |
4930 | */ | |
506458ef | 4931 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4932 | if (owner) { |
4933 | /* | |
4934 | * Since delayed_put_task_struct() also drops the last | |
4935 | * task reference we can safely take a new reference | |
4936 | * while holding the rcu_read_lock(). | |
4937 | */ | |
4938 | get_task_struct(owner); | |
4939 | } | |
4940 | rcu_read_unlock(); | |
4941 | ||
4942 | if (owner) { | |
f63a8daa PZ |
4943 | /* |
4944 | * If we're here through perf_event_exit_task() we're already | |
4945 | * holding ctx->mutex which would be an inversion wrt. the | |
4946 | * normal lock order. | |
4947 | * | |
4948 | * However we can safely take this lock because its the child | |
4949 | * ctx->mutex. | |
4950 | */ | |
4951 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4952 | ||
8882135b PZ |
4953 | /* |
4954 | * We have to re-check the event->owner field, if it is cleared | |
4955 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4956 | * ensured they're done, and we can proceed with freeing the | |
4957 | * event. | |
4958 | */ | |
f47c02c0 | 4959 | if (event->owner) { |
8882135b | 4960 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4961 | smp_store_release(&event->owner, NULL); |
4962 | } | |
8882135b PZ |
4963 | mutex_unlock(&owner->perf_event_mutex); |
4964 | put_task_struct(owner); | |
4965 | } | |
f8697762 JO |
4966 | } |
4967 | ||
f8697762 JO |
4968 | static void put_event(struct perf_event *event) |
4969 | { | |
f8697762 JO |
4970 | if (!atomic_long_dec_and_test(&event->refcount)) |
4971 | return; | |
4972 | ||
c6e5b732 PZ |
4973 | _free_event(event); |
4974 | } | |
4975 | ||
4976 | /* | |
4977 | * Kill an event dead; while event:refcount will preserve the event | |
4978 | * object, it will not preserve its functionality. Once the last 'user' | |
4979 | * gives up the object, we'll destroy the thing. | |
4980 | */ | |
4981 | int perf_event_release_kernel(struct perf_event *event) | |
4982 | { | |
a4f4bb6d | 4983 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4984 | struct perf_event *child, *tmp; |
82d94856 | 4985 | LIST_HEAD(free_list); |
c6e5b732 | 4986 | |
a4f4bb6d PZ |
4987 | /* |
4988 | * If we got here through err_file: fput(event_file); we will not have | |
4989 | * attached to a context yet. | |
4990 | */ | |
4991 | if (!ctx) { | |
4992 | WARN_ON_ONCE(event->attach_state & | |
4993 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4994 | goto no_ctx; | |
4995 | } | |
4996 | ||
f8697762 JO |
4997 | if (!is_kernel_event(event)) |
4998 | perf_remove_from_owner(event); | |
8882135b | 4999 | |
5fa7c8ec | 5000 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 5001 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 5002 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 5003 | |
a69b0ca4 | 5004 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 5005 | /* |
d8a8cfc7 | 5006 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 5007 | * anymore. |
683ede43 | 5008 | * |
a69b0ca4 PZ |
5009 | * Anybody acquiring event->child_mutex after the below loop _must_ |
5010 | * also see this, most importantly inherit_event() which will avoid | |
5011 | * placing more children on the list. | |
683ede43 | 5012 | * |
c6e5b732 PZ |
5013 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
5014 | * child events. | |
683ede43 | 5015 | */ |
a69b0ca4 PZ |
5016 | event->state = PERF_EVENT_STATE_DEAD; |
5017 | raw_spin_unlock_irq(&ctx->lock); | |
5018 | ||
5019 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 5020 | |
c6e5b732 PZ |
5021 | again: |
5022 | mutex_lock(&event->child_mutex); | |
5023 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 5024 | |
c6e5b732 PZ |
5025 | /* |
5026 | * Cannot change, child events are not migrated, see the | |
5027 | * comment with perf_event_ctx_lock_nested(). | |
5028 | */ | |
506458ef | 5029 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
5030 | /* |
5031 | * Since child_mutex nests inside ctx::mutex, we must jump | |
5032 | * through hoops. We start by grabbing a reference on the ctx. | |
5033 | * | |
5034 | * Since the event cannot get freed while we hold the | |
5035 | * child_mutex, the context must also exist and have a !0 | |
5036 | * reference count. | |
5037 | */ | |
5038 | get_ctx(ctx); | |
5039 | ||
5040 | /* | |
5041 | * Now that we have a ctx ref, we can drop child_mutex, and | |
5042 | * acquire ctx::mutex without fear of it going away. Then we | |
5043 | * can re-acquire child_mutex. | |
5044 | */ | |
5045 | mutex_unlock(&event->child_mutex); | |
5046 | mutex_lock(&ctx->mutex); | |
5047 | mutex_lock(&event->child_mutex); | |
5048 | ||
5049 | /* | |
5050 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
5051 | * state, if child is still the first entry, it didn't get freed | |
5052 | * and we can continue doing so. | |
5053 | */ | |
5054 | tmp = list_first_entry_or_null(&event->child_list, | |
5055 | struct perf_event, child_list); | |
5056 | if (tmp == child) { | |
5057 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 5058 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
5059 | /* |
5060 | * This matches the refcount bump in inherit_event(); | |
5061 | * this can't be the last reference. | |
5062 | */ | |
5063 | put_event(event); | |
5064 | } | |
5065 | ||
5066 | mutex_unlock(&event->child_mutex); | |
5067 | mutex_unlock(&ctx->mutex); | |
5068 | put_ctx(ctx); | |
5069 | goto again; | |
5070 | } | |
5071 | mutex_unlock(&event->child_mutex); | |
5072 | ||
82d94856 | 5073 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
5074 | void *var = &child->ctx->refcount; |
5075 | ||
82d94856 PZ |
5076 | list_del(&child->child_list); |
5077 | free_event(child); | |
1cf8dfe8 PZ |
5078 | |
5079 | /* | |
5080 | * Wake any perf_event_free_task() waiting for this event to be | |
5081 | * freed. | |
5082 | */ | |
5083 | smp_mb(); /* pairs with wait_var_event() */ | |
5084 | wake_up_var(var); | |
82d94856 PZ |
5085 | } |
5086 | ||
a4f4bb6d PZ |
5087 | no_ctx: |
5088 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
5089 | return 0; |
5090 | } | |
5091 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
5092 | ||
8b10c5e2 PZ |
5093 | /* |
5094 | * Called when the last reference to the file is gone. | |
5095 | */ | |
a6fa941d AV |
5096 | static int perf_release(struct inode *inode, struct file *file) |
5097 | { | |
c6e5b732 | 5098 | perf_event_release_kernel(file->private_data); |
a6fa941d | 5099 | return 0; |
fb0459d7 | 5100 | } |
fb0459d7 | 5101 | |
ca0dd44c | 5102 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 5103 | { |
cdd6c482 | 5104 | struct perf_event *child; |
e53c0994 PZ |
5105 | u64 total = 0; |
5106 | ||
59ed446f PZ |
5107 | *enabled = 0; |
5108 | *running = 0; | |
5109 | ||
6f10581a | 5110 | mutex_lock(&event->child_mutex); |
01add3ea | 5111 | |
7d88962e | 5112 | (void)perf_event_read(event, false); |
01add3ea SB |
5113 | total += perf_event_count(event); |
5114 | ||
59ed446f PZ |
5115 | *enabled += event->total_time_enabled + |
5116 | atomic64_read(&event->child_total_time_enabled); | |
5117 | *running += event->total_time_running + | |
5118 | atomic64_read(&event->child_total_time_running); | |
5119 | ||
5120 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5121 | (void)perf_event_read(child, false); |
01add3ea | 5122 | total += perf_event_count(child); |
59ed446f PZ |
5123 | *enabled += child->total_time_enabled; |
5124 | *running += child->total_time_running; | |
5125 | } | |
6f10581a | 5126 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5127 | |
5128 | return total; | |
5129 | } | |
ca0dd44c PZ |
5130 | |
5131 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5132 | { | |
5133 | struct perf_event_context *ctx; | |
5134 | u64 count; | |
5135 | ||
5136 | ctx = perf_event_ctx_lock(event); | |
5137 | count = __perf_event_read_value(event, enabled, running); | |
5138 | perf_event_ctx_unlock(event, ctx); | |
5139 | ||
5140 | return count; | |
5141 | } | |
fb0459d7 | 5142 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5143 | |
7d88962e | 5144 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5145 | u64 read_format, u64 *values) |
3dab77fb | 5146 | { |
2aeb1883 | 5147 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5148 | struct perf_event *sub; |
2aeb1883 | 5149 | unsigned long flags; |
fa8c2693 | 5150 | int n = 1; /* skip @nr */ |
7d88962e | 5151 | int ret; |
f63a8daa | 5152 | |
7d88962e SB |
5153 | ret = perf_event_read(leader, true); |
5154 | if (ret) | |
5155 | return ret; | |
abf4868b | 5156 | |
a9cd8194 PZ |
5157 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5158 | ||
fa8c2693 PZ |
5159 | /* |
5160 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5161 | * will be identical to those of the leader, so we only publish one | |
5162 | * set. | |
5163 | */ | |
5164 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5165 | values[n++] += leader->total_time_enabled + | |
5166 | atomic64_read(&leader->child_total_time_enabled); | |
5167 | } | |
3dab77fb | 5168 | |
fa8c2693 PZ |
5169 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5170 | values[n++] += leader->total_time_running + | |
5171 | atomic64_read(&leader->child_total_time_running); | |
5172 | } | |
5173 | ||
5174 | /* | |
5175 | * Write {count,id} tuples for every sibling. | |
5176 | */ | |
5177 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5178 | if (read_format & PERF_FORMAT_ID) |
5179 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5180 | |
edb39592 | 5181 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5182 | values[n++] += perf_event_count(sub); |
5183 | if (read_format & PERF_FORMAT_ID) | |
5184 | values[n++] = primary_event_id(sub); | |
5185 | } | |
7d88962e | 5186 | |
2aeb1883 | 5187 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5188 | return 0; |
fa8c2693 | 5189 | } |
3dab77fb | 5190 | |
fa8c2693 PZ |
5191 | static int perf_read_group(struct perf_event *event, |
5192 | u64 read_format, char __user *buf) | |
5193 | { | |
5194 | struct perf_event *leader = event->group_leader, *child; | |
5195 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5196 | int ret; |
fa8c2693 | 5197 | u64 *values; |
3dab77fb | 5198 | |
fa8c2693 | 5199 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5200 | |
fa8c2693 PZ |
5201 | values = kzalloc(event->read_size, GFP_KERNEL); |
5202 | if (!values) | |
5203 | return -ENOMEM; | |
3dab77fb | 5204 | |
fa8c2693 PZ |
5205 | values[0] = 1 + leader->nr_siblings; |
5206 | ||
5207 | /* | |
5208 | * By locking the child_mutex of the leader we effectively | |
5209 | * lock the child list of all siblings.. XXX explain how. | |
5210 | */ | |
5211 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5212 | |
7d88962e SB |
5213 | ret = __perf_read_group_add(leader, read_format, values); |
5214 | if (ret) | |
5215 | goto unlock; | |
5216 | ||
5217 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5218 | ret = __perf_read_group_add(child, read_format, values); | |
5219 | if (ret) | |
5220 | goto unlock; | |
5221 | } | |
abf4868b | 5222 | |
fa8c2693 | 5223 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5224 | |
7d88962e | 5225 | ret = event->read_size; |
fa8c2693 PZ |
5226 | if (copy_to_user(buf, values, event->read_size)) |
5227 | ret = -EFAULT; | |
7d88962e | 5228 | goto out; |
fa8c2693 | 5229 | |
7d88962e SB |
5230 | unlock: |
5231 | mutex_unlock(&leader->child_mutex); | |
5232 | out: | |
fa8c2693 | 5233 | kfree(values); |
abf4868b | 5234 | return ret; |
3dab77fb PZ |
5235 | } |
5236 | ||
b15f495b | 5237 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5238 | u64 read_format, char __user *buf) |
5239 | { | |
59ed446f | 5240 | u64 enabled, running; |
3dab77fb PZ |
5241 | u64 values[4]; |
5242 | int n = 0; | |
5243 | ||
ca0dd44c | 5244 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5245 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5246 | values[n++] = enabled; | |
5247 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5248 | values[n++] = running; | |
3dab77fb | 5249 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5250 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5251 | |
5252 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5253 | return -EFAULT; | |
5254 | ||
5255 | return n * sizeof(u64); | |
5256 | } | |
5257 | ||
dc633982 JO |
5258 | static bool is_event_hup(struct perf_event *event) |
5259 | { | |
5260 | bool no_children; | |
5261 | ||
a69b0ca4 | 5262 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5263 | return false; |
5264 | ||
5265 | mutex_lock(&event->child_mutex); | |
5266 | no_children = list_empty(&event->child_list); | |
5267 | mutex_unlock(&event->child_mutex); | |
5268 | return no_children; | |
5269 | } | |
5270 | ||
0793a61d | 5271 | /* |
cdd6c482 | 5272 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5273 | */ |
5274 | static ssize_t | |
b15f495b | 5275 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5276 | { |
cdd6c482 | 5277 | u64 read_format = event->attr.read_format; |
3dab77fb | 5278 | int ret; |
0793a61d | 5279 | |
3b6f9e5c | 5280 | /* |
788faab7 | 5281 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5282 | * error state (i.e. because it was pinned but it couldn't be |
5283 | * scheduled on to the CPU at some point). | |
5284 | */ | |
cdd6c482 | 5285 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5286 | return 0; |
5287 | ||
c320c7b7 | 5288 | if (count < event->read_size) |
3dab77fb PZ |
5289 | return -ENOSPC; |
5290 | ||
cdd6c482 | 5291 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5292 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5293 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5294 | else |
b15f495b | 5295 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5296 | |
3dab77fb | 5297 | return ret; |
0793a61d TG |
5298 | } |
5299 | ||
0793a61d TG |
5300 | static ssize_t |
5301 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5302 | { | |
cdd6c482 | 5303 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5304 | struct perf_event_context *ctx; |
5305 | int ret; | |
0793a61d | 5306 | |
da97e184 JFG |
5307 | ret = security_perf_event_read(event); |
5308 | if (ret) | |
5309 | return ret; | |
5310 | ||
f63a8daa | 5311 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5312 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5313 | perf_event_ctx_unlock(event, ctx); |
5314 | ||
5315 | return ret; | |
0793a61d TG |
5316 | } |
5317 | ||
9dd95748 | 5318 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5319 | { |
cdd6c482 | 5320 | struct perf_event *event = file->private_data; |
56de4e8f | 5321 | struct perf_buffer *rb; |
a9a08845 | 5322 | __poll_t events = EPOLLHUP; |
c7138f37 | 5323 | |
e708d7ad | 5324 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5325 | |
dc633982 | 5326 | if (is_event_hup(event)) |
179033b3 | 5327 | return events; |
c7138f37 | 5328 | |
10c6db11 | 5329 | /* |
9bb5d40c PZ |
5330 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5331 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5332 | */ |
5333 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5334 | rb = event->rb; |
5335 | if (rb) | |
76369139 | 5336 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5337 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5338 | return events; |
5339 | } | |
5340 | ||
f63a8daa | 5341 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5342 | { |
7d88962e | 5343 | (void)perf_event_read(event, false); |
e7850595 | 5344 | local64_set(&event->count, 0); |
cdd6c482 | 5345 | perf_event_update_userpage(event); |
3df5edad PZ |
5346 | } |
5347 | ||
52ba4b0b LX |
5348 | /* Assume it's not an event with inherit set. */ |
5349 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5350 | { | |
5351 | struct perf_event_context *ctx; | |
5352 | u64 count; | |
5353 | ||
5354 | ctx = perf_event_ctx_lock(event); | |
5355 | WARN_ON_ONCE(event->attr.inherit); | |
5356 | _perf_event_disable(event); | |
5357 | count = local64_read(&event->count); | |
5358 | if (reset) | |
5359 | local64_set(&event->count, 0); | |
5360 | perf_event_ctx_unlock(event, ctx); | |
5361 | ||
5362 | return count; | |
5363 | } | |
5364 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5365 | ||
c93f7669 | 5366 | /* |
cdd6c482 IM |
5367 | * Holding the top-level event's child_mutex means that any |
5368 | * descendant process that has inherited this event will block | |
8ba289b8 | 5369 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5370 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5371 | */ |
cdd6c482 IM |
5372 | static void perf_event_for_each_child(struct perf_event *event, |
5373 | void (*func)(struct perf_event *)) | |
3df5edad | 5374 | { |
cdd6c482 | 5375 | struct perf_event *child; |
3df5edad | 5376 | |
cdd6c482 | 5377 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5378 | |
cdd6c482 IM |
5379 | mutex_lock(&event->child_mutex); |
5380 | func(event); | |
5381 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5382 | func(child); |
cdd6c482 | 5383 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5384 | } |
5385 | ||
cdd6c482 IM |
5386 | static void perf_event_for_each(struct perf_event *event, |
5387 | void (*func)(struct perf_event *)) | |
3df5edad | 5388 | { |
cdd6c482 IM |
5389 | struct perf_event_context *ctx = event->ctx; |
5390 | struct perf_event *sibling; | |
3df5edad | 5391 | |
f63a8daa PZ |
5392 | lockdep_assert_held(&ctx->mutex); |
5393 | ||
cdd6c482 | 5394 | event = event->group_leader; |
75f937f2 | 5395 | |
cdd6c482 | 5396 | perf_event_for_each_child(event, func); |
edb39592 | 5397 | for_each_sibling_event(sibling, event) |
724b6daa | 5398 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5399 | } |
5400 | ||
fae3fde6 PZ |
5401 | static void __perf_event_period(struct perf_event *event, |
5402 | struct perf_cpu_context *cpuctx, | |
5403 | struct perf_event_context *ctx, | |
5404 | void *info) | |
c7999c6f | 5405 | { |
fae3fde6 | 5406 | u64 value = *((u64 *)info); |
c7999c6f | 5407 | bool active; |
08247e31 | 5408 | |
cdd6c482 | 5409 | if (event->attr.freq) { |
cdd6c482 | 5410 | event->attr.sample_freq = value; |
08247e31 | 5411 | } else { |
cdd6c482 IM |
5412 | event->attr.sample_period = value; |
5413 | event->hw.sample_period = value; | |
08247e31 | 5414 | } |
bad7192b PZ |
5415 | |
5416 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5417 | if (active) { | |
5418 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5419 | /* |
5420 | * We could be throttled; unthrottle now to avoid the tick | |
5421 | * trying to unthrottle while we already re-started the event. | |
5422 | */ | |
5423 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5424 | event->hw.interrupts = 0; | |
5425 | perf_log_throttle(event, 1); | |
5426 | } | |
bad7192b PZ |
5427 | event->pmu->stop(event, PERF_EF_UPDATE); |
5428 | } | |
5429 | ||
5430 | local64_set(&event->hw.period_left, 0); | |
5431 | ||
5432 | if (active) { | |
5433 | event->pmu->start(event, PERF_EF_RELOAD); | |
5434 | perf_pmu_enable(ctx->pmu); | |
5435 | } | |
c7999c6f PZ |
5436 | } |
5437 | ||
81ec3f3c JO |
5438 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5439 | { | |
5440 | return event->pmu->check_period(event, value); | |
5441 | } | |
5442 | ||
3ca270fc | 5443 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5444 | { |
c7999c6f PZ |
5445 | if (!is_sampling_event(event)) |
5446 | return -EINVAL; | |
5447 | ||
c7999c6f PZ |
5448 | if (!value) |
5449 | return -EINVAL; | |
5450 | ||
5451 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5452 | return -EINVAL; | |
5453 | ||
81ec3f3c JO |
5454 | if (perf_event_check_period(event, value)) |
5455 | return -EINVAL; | |
5456 | ||
913a90bc RB |
5457 | if (!event->attr.freq && (value & (1ULL << 63))) |
5458 | return -EINVAL; | |
5459 | ||
fae3fde6 | 5460 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5461 | |
c7999c6f | 5462 | return 0; |
08247e31 PZ |
5463 | } |
5464 | ||
3ca270fc LX |
5465 | int perf_event_period(struct perf_event *event, u64 value) |
5466 | { | |
5467 | struct perf_event_context *ctx; | |
5468 | int ret; | |
5469 | ||
5470 | ctx = perf_event_ctx_lock(event); | |
5471 | ret = _perf_event_period(event, value); | |
5472 | perf_event_ctx_unlock(event, ctx); | |
5473 | ||
5474 | return ret; | |
5475 | } | |
5476 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5477 | ||
ac9721f3 PZ |
5478 | static const struct file_operations perf_fops; |
5479 | ||
2903ff01 | 5480 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5481 | { |
2903ff01 AV |
5482 | struct fd f = fdget(fd); |
5483 | if (!f.file) | |
5484 | return -EBADF; | |
ac9721f3 | 5485 | |
2903ff01 AV |
5486 | if (f.file->f_op != &perf_fops) { |
5487 | fdput(f); | |
5488 | return -EBADF; | |
ac9721f3 | 5489 | } |
2903ff01 AV |
5490 | *p = f; |
5491 | return 0; | |
ac9721f3 PZ |
5492 | } |
5493 | ||
5494 | static int perf_event_set_output(struct perf_event *event, | |
5495 | struct perf_event *output_event); | |
6fb2915d | 5496 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5497 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5498 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5499 | struct perf_event_attr *attr); | |
a4be7c27 | 5500 | |
f63a8daa | 5501 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5502 | { |
cdd6c482 | 5503 | void (*func)(struct perf_event *); |
3df5edad | 5504 | u32 flags = arg; |
d859e29f PM |
5505 | |
5506 | switch (cmd) { | |
cdd6c482 | 5507 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5508 | func = _perf_event_enable; |
d859e29f | 5509 | break; |
cdd6c482 | 5510 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5511 | func = _perf_event_disable; |
79f14641 | 5512 | break; |
cdd6c482 | 5513 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5514 | func = _perf_event_reset; |
6de6a7b9 | 5515 | break; |
3df5edad | 5516 | |
cdd6c482 | 5517 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5518 | return _perf_event_refresh(event, arg); |
08247e31 | 5519 | |
cdd6c482 | 5520 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5521 | { |
5522 | u64 value; | |
08247e31 | 5523 | |
3ca270fc LX |
5524 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5525 | return -EFAULT; | |
08247e31 | 5526 | |
3ca270fc LX |
5527 | return _perf_event_period(event, value); |
5528 | } | |
cf4957f1 JO |
5529 | case PERF_EVENT_IOC_ID: |
5530 | { | |
5531 | u64 id = primary_event_id(event); | |
5532 | ||
5533 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5534 | return -EFAULT; | |
5535 | return 0; | |
5536 | } | |
5537 | ||
cdd6c482 | 5538 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5539 | { |
ac9721f3 | 5540 | int ret; |
ac9721f3 | 5541 | if (arg != -1) { |
2903ff01 AV |
5542 | struct perf_event *output_event; |
5543 | struct fd output; | |
5544 | ret = perf_fget_light(arg, &output); | |
5545 | if (ret) | |
5546 | return ret; | |
5547 | output_event = output.file->private_data; | |
5548 | ret = perf_event_set_output(event, output_event); | |
5549 | fdput(output); | |
5550 | } else { | |
5551 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5552 | } |
ac9721f3 PZ |
5553 | return ret; |
5554 | } | |
a4be7c27 | 5555 | |
6fb2915d LZ |
5556 | case PERF_EVENT_IOC_SET_FILTER: |
5557 | return perf_event_set_filter(event, (void __user *)arg); | |
5558 | ||
2541517c AS |
5559 | case PERF_EVENT_IOC_SET_BPF: |
5560 | return perf_event_set_bpf_prog(event, arg); | |
5561 | ||
86e7972f | 5562 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5563 | struct perf_buffer *rb; |
86e7972f WN |
5564 | |
5565 | rcu_read_lock(); | |
5566 | rb = rcu_dereference(event->rb); | |
5567 | if (!rb || !rb->nr_pages) { | |
5568 | rcu_read_unlock(); | |
5569 | return -EINVAL; | |
5570 | } | |
5571 | rb_toggle_paused(rb, !!arg); | |
5572 | rcu_read_unlock(); | |
5573 | return 0; | |
5574 | } | |
f371b304 YS |
5575 | |
5576 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5577 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5578 | |
5579 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5580 | struct perf_event_attr new_attr; | |
5581 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5582 | &new_attr); | |
5583 | ||
5584 | if (err) | |
5585 | return err; | |
5586 | ||
5587 | return perf_event_modify_attr(event, &new_attr); | |
5588 | } | |
d859e29f | 5589 | default: |
3df5edad | 5590 | return -ENOTTY; |
d859e29f | 5591 | } |
3df5edad PZ |
5592 | |
5593 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5594 | perf_event_for_each(event, func); |
3df5edad | 5595 | else |
cdd6c482 | 5596 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5597 | |
5598 | return 0; | |
d859e29f PM |
5599 | } |
5600 | ||
f63a8daa PZ |
5601 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5602 | { | |
5603 | struct perf_event *event = file->private_data; | |
5604 | struct perf_event_context *ctx; | |
5605 | long ret; | |
5606 | ||
da97e184 JFG |
5607 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5608 | ret = security_perf_event_write(event); | |
5609 | if (ret) | |
5610 | return ret; | |
5611 | ||
f63a8daa PZ |
5612 | ctx = perf_event_ctx_lock(event); |
5613 | ret = _perf_ioctl(event, cmd, arg); | |
5614 | perf_event_ctx_unlock(event, ctx); | |
5615 | ||
5616 | return ret; | |
5617 | } | |
5618 | ||
b3f20785 PM |
5619 | #ifdef CONFIG_COMPAT |
5620 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5621 | unsigned long arg) | |
5622 | { | |
5623 | switch (_IOC_NR(cmd)) { | |
5624 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5625 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5626 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5627 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5628 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5629 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5630 | cmd &= ~IOCSIZE_MASK; | |
5631 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5632 | } | |
5633 | break; | |
5634 | } | |
5635 | return perf_ioctl(file, cmd, arg); | |
5636 | } | |
5637 | #else | |
5638 | # define perf_compat_ioctl NULL | |
5639 | #endif | |
5640 | ||
cdd6c482 | 5641 | int perf_event_task_enable(void) |
771d7cde | 5642 | { |
f63a8daa | 5643 | struct perf_event_context *ctx; |
cdd6c482 | 5644 | struct perf_event *event; |
771d7cde | 5645 | |
cdd6c482 | 5646 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5647 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5648 | ctx = perf_event_ctx_lock(event); | |
5649 | perf_event_for_each_child(event, _perf_event_enable); | |
5650 | perf_event_ctx_unlock(event, ctx); | |
5651 | } | |
cdd6c482 | 5652 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5653 | |
5654 | return 0; | |
5655 | } | |
5656 | ||
cdd6c482 | 5657 | int perf_event_task_disable(void) |
771d7cde | 5658 | { |
f63a8daa | 5659 | struct perf_event_context *ctx; |
cdd6c482 | 5660 | struct perf_event *event; |
771d7cde | 5661 | |
cdd6c482 | 5662 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5663 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5664 | ctx = perf_event_ctx_lock(event); | |
5665 | perf_event_for_each_child(event, _perf_event_disable); | |
5666 | perf_event_ctx_unlock(event, ctx); | |
5667 | } | |
cdd6c482 | 5668 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5669 | |
5670 | return 0; | |
5671 | } | |
5672 | ||
cdd6c482 | 5673 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5674 | { |
a4eaf7f1 PZ |
5675 | if (event->hw.state & PERF_HES_STOPPED) |
5676 | return 0; | |
5677 | ||
cdd6c482 | 5678 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5679 | return 0; |
5680 | ||
35edc2a5 | 5681 | return event->pmu->event_idx(event); |
194002b2 PZ |
5682 | } |
5683 | ||
c4794295 | 5684 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5685 | u64 *now, |
7f310a5d EM |
5686 | u64 *enabled, |
5687 | u64 *running) | |
c4794295 | 5688 | { |
e3f3541c | 5689 | u64 ctx_time; |
c4794295 | 5690 | |
e3f3541c PZ |
5691 | *now = perf_clock(); |
5692 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5693 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5694 | } |
5695 | ||
fa731587 PZ |
5696 | static void perf_event_init_userpage(struct perf_event *event) |
5697 | { | |
5698 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5699 | struct perf_buffer *rb; |
fa731587 PZ |
5700 | |
5701 | rcu_read_lock(); | |
5702 | rb = rcu_dereference(event->rb); | |
5703 | if (!rb) | |
5704 | goto unlock; | |
5705 | ||
5706 | userpg = rb->user_page; | |
5707 | ||
5708 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5709 | userpg->cap_bit0_is_deprecated = 1; | |
5710 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5711 | userpg->data_offset = PAGE_SIZE; |
5712 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5713 | |
5714 | unlock: | |
5715 | rcu_read_unlock(); | |
5716 | } | |
5717 | ||
c1317ec2 AL |
5718 | void __weak arch_perf_update_userpage( |
5719 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5720 | { |
5721 | } | |
5722 | ||
38ff667b PZ |
5723 | /* |
5724 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5725 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5726 | * code calls this from NMI context. | |
5727 | */ | |
cdd6c482 | 5728 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5729 | { |
cdd6c482 | 5730 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5731 | struct perf_buffer *rb; |
e3f3541c | 5732 | u64 enabled, running, now; |
38ff667b PZ |
5733 | |
5734 | rcu_read_lock(); | |
5ec4c599 PZ |
5735 | rb = rcu_dereference(event->rb); |
5736 | if (!rb) | |
5737 | goto unlock; | |
5738 | ||
0d641208 EM |
5739 | /* |
5740 | * compute total_time_enabled, total_time_running | |
5741 | * based on snapshot values taken when the event | |
5742 | * was last scheduled in. | |
5743 | * | |
5744 | * we cannot simply called update_context_time() | |
5745 | * because of locking issue as we can be called in | |
5746 | * NMI context | |
5747 | */ | |
e3f3541c | 5748 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5749 | |
76369139 | 5750 | userpg = rb->user_page; |
7b732a75 | 5751 | /* |
9d2dcc8f MF |
5752 | * Disable preemption to guarantee consistent time stamps are stored to |
5753 | * the user page. | |
7b732a75 PZ |
5754 | */ |
5755 | preempt_disable(); | |
37d81828 | 5756 | ++userpg->lock; |
92f22a38 | 5757 | barrier(); |
cdd6c482 | 5758 | userpg->index = perf_event_index(event); |
b5e58793 | 5759 | userpg->offset = perf_event_count(event); |
365a4038 | 5760 | if (userpg->index) |
e7850595 | 5761 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5762 | |
0d641208 | 5763 | userpg->time_enabled = enabled + |
cdd6c482 | 5764 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5765 | |
0d641208 | 5766 | userpg->time_running = running + |
cdd6c482 | 5767 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5768 | |
c1317ec2 | 5769 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5770 | |
92f22a38 | 5771 | barrier(); |
37d81828 | 5772 | ++userpg->lock; |
7b732a75 | 5773 | preempt_enable(); |
38ff667b | 5774 | unlock: |
7b732a75 | 5775 | rcu_read_unlock(); |
37d81828 | 5776 | } |
82975c46 | 5777 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5778 | |
9e3ed2d7 | 5779 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5780 | { |
11bac800 | 5781 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5782 | struct perf_buffer *rb; |
9e3ed2d7 | 5783 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5784 | |
5785 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5786 | if (vmf->pgoff == 0) | |
5787 | ret = 0; | |
5788 | return ret; | |
5789 | } | |
5790 | ||
5791 | rcu_read_lock(); | |
76369139 FW |
5792 | rb = rcu_dereference(event->rb); |
5793 | if (!rb) | |
906010b2 PZ |
5794 | goto unlock; |
5795 | ||
5796 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5797 | goto unlock; | |
5798 | ||
76369139 | 5799 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5800 | if (!vmf->page) |
5801 | goto unlock; | |
5802 | ||
5803 | get_page(vmf->page); | |
11bac800 | 5804 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5805 | vmf->page->index = vmf->pgoff; |
5806 | ||
5807 | ret = 0; | |
5808 | unlock: | |
5809 | rcu_read_unlock(); | |
5810 | ||
5811 | return ret; | |
5812 | } | |
5813 | ||
10c6db11 | 5814 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5815 | struct perf_buffer *rb) |
10c6db11 | 5816 | { |
56de4e8f | 5817 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5818 | unsigned long flags; |
5819 | ||
b69cf536 PZ |
5820 | if (event->rb) { |
5821 | /* | |
5822 | * Should be impossible, we set this when removing | |
5823 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5824 | */ | |
5825 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5826 | |
b69cf536 | 5827 | old_rb = event->rb; |
b69cf536 PZ |
5828 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5829 | list_del_rcu(&event->rb_entry); | |
5830 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5831 | |
2f993cf0 ON |
5832 | event->rcu_batches = get_state_synchronize_rcu(); |
5833 | event->rcu_pending = 1; | |
b69cf536 | 5834 | } |
10c6db11 | 5835 | |
b69cf536 | 5836 | if (rb) { |
2f993cf0 ON |
5837 | if (event->rcu_pending) { |
5838 | cond_synchronize_rcu(event->rcu_batches); | |
5839 | event->rcu_pending = 0; | |
5840 | } | |
5841 | ||
b69cf536 PZ |
5842 | spin_lock_irqsave(&rb->event_lock, flags); |
5843 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5844 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5845 | } | |
5846 | ||
767ae086 AS |
5847 | /* |
5848 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5849 | * before swizzling the event::rb pointer; if it's getting | |
5850 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5851 | * restart. See the comment in __perf_pmu_output_stop(). | |
5852 | * | |
5853 | * Data will inevitably be lost when set_output is done in | |
5854 | * mid-air, but then again, whoever does it like this is | |
5855 | * not in for the data anyway. | |
5856 | */ | |
5857 | if (has_aux(event)) | |
5858 | perf_event_stop(event, 0); | |
5859 | ||
b69cf536 PZ |
5860 | rcu_assign_pointer(event->rb, rb); |
5861 | ||
5862 | if (old_rb) { | |
5863 | ring_buffer_put(old_rb); | |
5864 | /* | |
5865 | * Since we detached before setting the new rb, so that we | |
5866 | * could attach the new rb, we could have missed a wakeup. | |
5867 | * Provide it now. | |
5868 | */ | |
5869 | wake_up_all(&event->waitq); | |
5870 | } | |
10c6db11 PZ |
5871 | } |
5872 | ||
5873 | static void ring_buffer_wakeup(struct perf_event *event) | |
5874 | { | |
56de4e8f | 5875 | struct perf_buffer *rb; |
10c6db11 PZ |
5876 | |
5877 | rcu_read_lock(); | |
5878 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5879 | if (rb) { |
5880 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5881 | wake_up_all(&event->waitq); | |
5882 | } | |
10c6db11 PZ |
5883 | rcu_read_unlock(); |
5884 | } | |
5885 | ||
56de4e8f | 5886 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5887 | { |
56de4e8f | 5888 | struct perf_buffer *rb; |
7b732a75 | 5889 | |
ac9721f3 | 5890 | rcu_read_lock(); |
76369139 FW |
5891 | rb = rcu_dereference(event->rb); |
5892 | if (rb) { | |
fecb8ed2 | 5893 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5894 | rb = NULL; |
ac9721f3 PZ |
5895 | } |
5896 | rcu_read_unlock(); | |
5897 | ||
76369139 | 5898 | return rb; |
ac9721f3 PZ |
5899 | } |
5900 | ||
56de4e8f | 5901 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5902 | { |
fecb8ed2 | 5903 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5904 | return; |
7b732a75 | 5905 | |
9bb5d40c | 5906 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5907 | |
76369139 | 5908 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5909 | } |
5910 | ||
5911 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5912 | { | |
cdd6c482 | 5913 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5914 | |
cdd6c482 | 5915 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5916 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5917 | |
45bfb2e5 PZ |
5918 | if (vma->vm_pgoff) |
5919 | atomic_inc(&event->rb->aux_mmap_count); | |
5920 | ||
1e0fb9ec | 5921 | if (event->pmu->event_mapped) |
bfe33492 | 5922 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5923 | } |
5924 | ||
95ff4ca2 AS |
5925 | static void perf_pmu_output_stop(struct perf_event *event); |
5926 | ||
9bb5d40c PZ |
5927 | /* |
5928 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5929 | * event, or through other events by use of perf_event_set_output(). | |
5930 | * | |
5931 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5932 | * the buffer here, where we still have a VM context. This means we need | |
5933 | * to detach all events redirecting to us. | |
5934 | */ | |
7b732a75 PZ |
5935 | static void perf_mmap_close(struct vm_area_struct *vma) |
5936 | { | |
cdd6c482 | 5937 | struct perf_event *event = vma->vm_file->private_data; |
56de4e8f | 5938 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5939 | struct user_struct *mmap_user = rb->mmap_user; |
5940 | int mmap_locked = rb->mmap_locked; | |
5941 | unsigned long size = perf_data_size(rb); | |
f91072ed | 5942 | bool detach_rest = false; |
789f90fc | 5943 | |
1e0fb9ec | 5944 | if (event->pmu->event_unmapped) |
bfe33492 | 5945 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5946 | |
45bfb2e5 PZ |
5947 | /* |
5948 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5949 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5950 | * serialize with perf_mmap here. | |
5951 | */ | |
5952 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5953 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5954 | /* |
5955 | * Stop all AUX events that are writing to this buffer, | |
5956 | * so that we can free its AUX pages and corresponding PMU | |
5957 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5958 | * they won't start any more (see perf_aux_output_begin()). | |
5959 | */ | |
5960 | perf_pmu_output_stop(event); | |
5961 | ||
5962 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5963 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5964 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5965 | |
95ff4ca2 | 5966 | /* this has to be the last one */ |
45bfb2e5 | 5967 | rb_free_aux(rb); |
ca3bb3d0 | 5968 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5969 | |
45bfb2e5 PZ |
5970 | mutex_unlock(&event->mmap_mutex); |
5971 | } | |
5972 | ||
f91072ed JO |
5973 | if (atomic_dec_and_test(&rb->mmap_count)) |
5974 | detach_rest = true; | |
9bb5d40c PZ |
5975 | |
5976 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5977 | goto out_put; |
9bb5d40c | 5978 | |
b69cf536 | 5979 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5980 | mutex_unlock(&event->mmap_mutex); |
5981 | ||
5982 | /* If there's still other mmap()s of this buffer, we're done. */ | |
f91072ed | 5983 | if (!detach_rest) |
b69cf536 | 5984 | goto out_put; |
ac9721f3 | 5985 | |
9bb5d40c PZ |
5986 | /* |
5987 | * No other mmap()s, detach from all other events that might redirect | |
5988 | * into the now unreachable buffer. Somewhat complicated by the | |
5989 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5990 | */ | |
5991 | again: | |
5992 | rcu_read_lock(); | |
5993 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5994 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5995 | /* | |
5996 | * This event is en-route to free_event() which will | |
5997 | * detach it and remove it from the list. | |
5998 | */ | |
5999 | continue; | |
6000 | } | |
6001 | rcu_read_unlock(); | |
789f90fc | 6002 | |
9bb5d40c PZ |
6003 | mutex_lock(&event->mmap_mutex); |
6004 | /* | |
6005 | * Check we didn't race with perf_event_set_output() which can | |
6006 | * swizzle the rb from under us while we were waiting to | |
6007 | * acquire mmap_mutex. | |
6008 | * | |
6009 | * If we find a different rb; ignore this event, a next | |
6010 | * iteration will no longer find it on the list. We have to | |
6011 | * still restart the iteration to make sure we're not now | |
6012 | * iterating the wrong list. | |
6013 | */ | |
b69cf536 PZ |
6014 | if (event->rb == rb) |
6015 | ring_buffer_attach(event, NULL); | |
6016 | ||
cdd6c482 | 6017 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 6018 | put_event(event); |
ac9721f3 | 6019 | |
9bb5d40c PZ |
6020 | /* |
6021 | * Restart the iteration; either we're on the wrong list or | |
6022 | * destroyed its integrity by doing a deletion. | |
6023 | */ | |
6024 | goto again; | |
7b732a75 | 6025 | } |
9bb5d40c PZ |
6026 | rcu_read_unlock(); |
6027 | ||
6028 | /* | |
6029 | * It could be there's still a few 0-ref events on the list; they'll | |
6030 | * get cleaned up by free_event() -- they'll also still have their | |
6031 | * ref on the rb and will free it whenever they are done with it. | |
6032 | * | |
6033 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
6034 | * undo the VM accounting. | |
6035 | */ | |
6036 | ||
d44248a4 SL |
6037 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
6038 | &mmap_user->locked_vm); | |
70f8a3ca | 6039 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
6040 | free_uid(mmap_user); |
6041 | ||
b69cf536 | 6042 | out_put: |
9bb5d40c | 6043 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
6044 | } |
6045 | ||
f0f37e2f | 6046 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 6047 | .open = perf_mmap_open, |
fca0c116 | 6048 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
6049 | .fault = perf_mmap_fault, |
6050 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
6051 | }; |
6052 | ||
6053 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
6054 | { | |
cdd6c482 | 6055 | struct perf_event *event = file->private_data; |
22a4f650 | 6056 | unsigned long user_locked, user_lock_limit; |
789f90fc | 6057 | struct user_struct *user = current_user(); |
56de4e8f | 6058 | struct perf_buffer *rb = NULL; |
22a4f650 | 6059 | unsigned long locked, lock_limit; |
7b732a75 PZ |
6060 | unsigned long vma_size; |
6061 | unsigned long nr_pages; | |
45bfb2e5 | 6062 | long user_extra = 0, extra = 0; |
d57e34fd | 6063 | int ret = 0, flags = 0; |
37d81828 | 6064 | |
c7920614 PZ |
6065 | /* |
6066 | * Don't allow mmap() of inherited per-task counters. This would | |
6067 | * create a performance issue due to all children writing to the | |
76369139 | 6068 | * same rb. |
c7920614 PZ |
6069 | */ |
6070 | if (event->cpu == -1 && event->attr.inherit) | |
6071 | return -EINVAL; | |
6072 | ||
43a21ea8 | 6073 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 6074 | return -EINVAL; |
7b732a75 | 6075 | |
da97e184 JFG |
6076 | ret = security_perf_event_read(event); |
6077 | if (ret) | |
6078 | return ret; | |
6079 | ||
7b732a75 | 6080 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
6081 | |
6082 | if (vma->vm_pgoff == 0) { | |
6083 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
6084 | } else { | |
6085 | /* | |
6086 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
6087 | * mapped, all subsequent mappings should have the same size | |
6088 | * and offset. Must be above the normal perf buffer. | |
6089 | */ | |
6090 | u64 aux_offset, aux_size; | |
6091 | ||
6092 | if (!event->rb) | |
6093 | return -EINVAL; | |
6094 | ||
6095 | nr_pages = vma_size / PAGE_SIZE; | |
6096 | ||
6097 | mutex_lock(&event->mmap_mutex); | |
6098 | ret = -EINVAL; | |
6099 | ||
6100 | rb = event->rb; | |
6101 | if (!rb) | |
6102 | goto aux_unlock; | |
6103 | ||
6aa7de05 MR |
6104 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
6105 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6106 | |
6107 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6108 | goto aux_unlock; | |
6109 | ||
6110 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6111 | goto aux_unlock; | |
6112 | ||
6113 | /* already mapped with a different offset */ | |
6114 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6115 | goto aux_unlock; | |
6116 | ||
6117 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6118 | goto aux_unlock; | |
6119 | ||
6120 | /* already mapped with a different size */ | |
6121 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6122 | goto aux_unlock; | |
6123 | ||
6124 | if (!is_power_of_2(nr_pages)) | |
6125 | goto aux_unlock; | |
6126 | ||
6127 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6128 | goto aux_unlock; | |
6129 | ||
6130 | if (rb_has_aux(rb)) { | |
6131 | atomic_inc(&rb->aux_mmap_count); | |
6132 | ret = 0; | |
6133 | goto unlock; | |
6134 | } | |
6135 | ||
6136 | atomic_set(&rb->aux_mmap_count, 1); | |
6137 | user_extra = nr_pages; | |
6138 | ||
6139 | goto accounting; | |
6140 | } | |
7b732a75 | 6141 | |
7730d865 | 6142 | /* |
76369139 | 6143 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6144 | * can do bitmasks instead of modulo. |
6145 | */ | |
2ed11312 | 6146 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6147 | return -EINVAL; |
6148 | ||
7b732a75 | 6149 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6150 | return -EINVAL; |
6151 | ||
cdd6c482 | 6152 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6153 | again: |
cdd6c482 | 6154 | mutex_lock(&event->mmap_mutex); |
76369139 | 6155 | if (event->rb) { |
9bb5d40c | 6156 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6157 | ret = -EINVAL; |
9bb5d40c PZ |
6158 | goto unlock; |
6159 | } | |
6160 | ||
6161 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6162 | /* | |
6163 | * Raced against perf_mmap_close() through | |
6164 | * perf_event_set_output(). Try again, hope for better | |
6165 | * luck. | |
6166 | */ | |
6167 | mutex_unlock(&event->mmap_mutex); | |
6168 | goto again; | |
6169 | } | |
6170 | ||
ebb3c4c4 PZ |
6171 | goto unlock; |
6172 | } | |
6173 | ||
789f90fc | 6174 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6175 | |
6176 | accounting: | |
cdd6c482 | 6177 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6178 | |
6179 | /* | |
6180 | * Increase the limit linearly with more CPUs: | |
6181 | */ | |
6182 | user_lock_limit *= num_online_cpus(); | |
6183 | ||
00346155 SL |
6184 | user_locked = atomic_long_read(&user->locked_vm); |
6185 | ||
6186 | /* | |
6187 | * sysctl_perf_event_mlock may have changed, so that | |
6188 | * user->locked_vm > user_lock_limit | |
6189 | */ | |
6190 | if (user_locked > user_lock_limit) | |
6191 | user_locked = user_lock_limit; | |
6192 | user_locked += user_extra; | |
c5078f78 | 6193 | |
c4b75479 | 6194 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6195 | /* |
6196 | * charge locked_vm until it hits user_lock_limit; | |
6197 | * charge the rest from pinned_vm | |
6198 | */ | |
789f90fc | 6199 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6200 | user_extra -= extra; |
6201 | } | |
7b732a75 | 6202 | |
78d7d407 | 6203 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6204 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6205 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6206 | |
da97e184 | 6207 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6208 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6209 | ret = -EPERM; |
6210 | goto unlock; | |
6211 | } | |
7b732a75 | 6212 | |
45bfb2e5 | 6213 | WARN_ON(!rb && event->rb); |
906010b2 | 6214 | |
d57e34fd | 6215 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6216 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6217 | |
76369139 | 6218 | if (!rb) { |
45bfb2e5 PZ |
6219 | rb = rb_alloc(nr_pages, |
6220 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6221 | event->cpu, flags); | |
26cb63ad | 6222 | |
45bfb2e5 PZ |
6223 | if (!rb) { |
6224 | ret = -ENOMEM; | |
6225 | goto unlock; | |
6226 | } | |
43a21ea8 | 6227 | |
45bfb2e5 PZ |
6228 | atomic_set(&rb->mmap_count, 1); |
6229 | rb->mmap_user = get_current_user(); | |
6230 | rb->mmap_locked = extra; | |
26cb63ad | 6231 | |
45bfb2e5 | 6232 | ring_buffer_attach(event, rb); |
ac9721f3 | 6233 | |
45bfb2e5 PZ |
6234 | perf_event_init_userpage(event); |
6235 | perf_event_update_userpage(event); | |
6236 | } else { | |
1a594131 AS |
6237 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6238 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6239 | if (!ret) |
6240 | rb->aux_mmap_locked = extra; | |
6241 | } | |
9a0f05cb | 6242 | |
ebb3c4c4 | 6243 | unlock: |
45bfb2e5 PZ |
6244 | if (!ret) { |
6245 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6246 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6247 | |
ac9721f3 | 6248 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6249 | } else if (rb) { |
6250 | atomic_dec(&rb->mmap_count); | |
6251 | } | |
6252 | aux_unlock: | |
cdd6c482 | 6253 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6254 | |
9bb5d40c PZ |
6255 | /* |
6256 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6257 | * vma. | |
6258 | */ | |
26cb63ad | 6259 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6260 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6261 | |
1e0fb9ec | 6262 | if (event->pmu->event_mapped) |
bfe33492 | 6263 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6264 | |
7b732a75 | 6265 | return ret; |
37d81828 PM |
6266 | } |
6267 | ||
3c446b3d PZ |
6268 | static int perf_fasync(int fd, struct file *filp, int on) |
6269 | { | |
496ad9aa | 6270 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6271 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6272 | int retval; |
6273 | ||
5955102c | 6274 | inode_lock(inode); |
cdd6c482 | 6275 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6276 | inode_unlock(inode); |
3c446b3d PZ |
6277 | |
6278 | if (retval < 0) | |
6279 | return retval; | |
6280 | ||
6281 | return 0; | |
6282 | } | |
6283 | ||
0793a61d | 6284 | static const struct file_operations perf_fops = { |
3326c1ce | 6285 | .llseek = no_llseek, |
0793a61d TG |
6286 | .release = perf_release, |
6287 | .read = perf_read, | |
6288 | .poll = perf_poll, | |
d859e29f | 6289 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6290 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6291 | .mmap = perf_mmap, |
3c446b3d | 6292 | .fasync = perf_fasync, |
0793a61d TG |
6293 | }; |
6294 | ||
925d519a | 6295 | /* |
cdd6c482 | 6296 | * Perf event wakeup |
925d519a PZ |
6297 | * |
6298 | * If there's data, ensure we set the poll() state and publish everything | |
6299 | * to user-space before waking everybody up. | |
6300 | */ | |
6301 | ||
fed66e2c PZ |
6302 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6303 | { | |
6304 | /* only the parent has fasync state */ | |
6305 | if (event->parent) | |
6306 | event = event->parent; | |
6307 | return &event->fasync; | |
6308 | } | |
6309 | ||
cdd6c482 | 6310 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6311 | { |
10c6db11 | 6312 | ring_buffer_wakeup(event); |
4c9e2542 | 6313 | |
cdd6c482 | 6314 | if (event->pending_kill) { |
fed66e2c | 6315 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6316 | event->pending_kill = 0; |
4c9e2542 | 6317 | } |
925d519a PZ |
6318 | } |
6319 | ||
1d54ad94 PZ |
6320 | static void perf_pending_event_disable(struct perf_event *event) |
6321 | { | |
6322 | int cpu = READ_ONCE(event->pending_disable); | |
6323 | ||
6324 | if (cpu < 0) | |
6325 | return; | |
6326 | ||
6327 | if (cpu == smp_processor_id()) { | |
6328 | WRITE_ONCE(event->pending_disable, -1); | |
6329 | perf_event_disable_local(event); | |
6330 | return; | |
6331 | } | |
6332 | ||
6333 | /* | |
6334 | * CPU-A CPU-B | |
6335 | * | |
6336 | * perf_event_disable_inatomic() | |
6337 | * @pending_disable = CPU-A; | |
6338 | * irq_work_queue(); | |
6339 | * | |
6340 | * sched-out | |
6341 | * @pending_disable = -1; | |
6342 | * | |
6343 | * sched-in | |
6344 | * perf_event_disable_inatomic() | |
6345 | * @pending_disable = CPU-B; | |
6346 | * irq_work_queue(); // FAILS | |
6347 | * | |
6348 | * irq_work_run() | |
6349 | * perf_pending_event() | |
6350 | * | |
6351 | * But the event runs on CPU-B and wants disabling there. | |
6352 | */ | |
6353 | irq_work_queue_on(&event->pending, cpu); | |
6354 | } | |
6355 | ||
e360adbe | 6356 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6357 | { |
1d54ad94 | 6358 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6359 | int rctx; |
6360 | ||
6361 | rctx = perf_swevent_get_recursion_context(); | |
6362 | /* | |
6363 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6364 | * and we won't recurse 'further'. | |
6365 | */ | |
79f14641 | 6366 | |
1d54ad94 | 6367 | perf_pending_event_disable(event); |
79f14641 | 6368 | |
cdd6c482 IM |
6369 | if (event->pending_wakeup) { |
6370 | event->pending_wakeup = 0; | |
6371 | perf_event_wakeup(event); | |
79f14641 | 6372 | } |
d525211f PZ |
6373 | |
6374 | if (rctx >= 0) | |
6375 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6376 | } |
6377 | ||
39447b38 ZY |
6378 | /* |
6379 | * We assume there is only KVM supporting the callbacks. | |
6380 | * Later on, we might change it to a list if there is | |
6381 | * another virtualization implementation supporting the callbacks. | |
6382 | */ | |
6383 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6384 | ||
6385 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6386 | { | |
6387 | perf_guest_cbs = cbs; | |
6388 | return 0; | |
6389 | } | |
6390 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6391 | ||
6392 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6393 | { | |
6394 | perf_guest_cbs = NULL; | |
6395 | return 0; | |
6396 | } | |
6397 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6398 | ||
4018994f JO |
6399 | static void |
6400 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6401 | struct pt_regs *regs, u64 mask) | |
6402 | { | |
6403 | int bit; | |
29dd3288 | 6404 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6405 | |
29dd3288 MS |
6406 | bitmap_from_u64(_mask, mask); |
6407 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6408 | u64 val; |
6409 | ||
6410 | val = perf_reg_value(regs, bit); | |
6411 | perf_output_put(handle, val); | |
6412 | } | |
6413 | } | |
6414 | ||
60e2364e | 6415 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
76a4efa8 | 6416 | struct pt_regs *regs) |
4018994f | 6417 | { |
88a7c26a AL |
6418 | if (user_mode(regs)) { |
6419 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6420 | regs_user->regs = regs; |
085ebfe9 | 6421 | } else if (!(current->flags & PF_KTHREAD)) { |
76a4efa8 | 6422 | perf_get_regs_user(regs_user, regs); |
2565711f PZ |
6423 | } else { |
6424 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6425 | regs_user->regs = NULL; | |
4018994f JO |
6426 | } |
6427 | } | |
6428 | ||
60e2364e SE |
6429 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6430 | struct pt_regs *regs) | |
6431 | { | |
6432 | regs_intr->regs = regs; | |
6433 | regs_intr->abi = perf_reg_abi(current); | |
6434 | } | |
6435 | ||
6436 | ||
c5ebcedb JO |
6437 | /* |
6438 | * Get remaining task size from user stack pointer. | |
6439 | * | |
6440 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6441 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6442 | * so using TASK_SIZE as limit. |
6443 | */ | |
6444 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6445 | { | |
6446 | unsigned long addr = perf_user_stack_pointer(regs); | |
6447 | ||
6448 | if (!addr || addr >= TASK_SIZE) | |
6449 | return 0; | |
6450 | ||
6451 | return TASK_SIZE - addr; | |
6452 | } | |
6453 | ||
6454 | static u16 | |
6455 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6456 | struct pt_regs *regs) | |
6457 | { | |
6458 | u64 task_size; | |
6459 | ||
6460 | /* No regs, no stack pointer, no dump. */ | |
6461 | if (!regs) | |
6462 | return 0; | |
6463 | ||
6464 | /* | |
6465 | * Check if we fit in with the requested stack size into the: | |
6466 | * - TASK_SIZE | |
6467 | * If we don't, we limit the size to the TASK_SIZE. | |
6468 | * | |
6469 | * - remaining sample size | |
6470 | * If we don't, we customize the stack size to | |
6471 | * fit in to the remaining sample size. | |
6472 | */ | |
6473 | ||
6474 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6475 | stack_size = min(stack_size, (u16) task_size); | |
6476 | ||
6477 | /* Current header size plus static size and dynamic size. */ | |
6478 | header_size += 2 * sizeof(u64); | |
6479 | ||
6480 | /* Do we fit in with the current stack dump size? */ | |
6481 | if ((u16) (header_size + stack_size) < header_size) { | |
6482 | /* | |
6483 | * If we overflow the maximum size for the sample, | |
6484 | * we customize the stack dump size to fit in. | |
6485 | */ | |
6486 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6487 | stack_size = round_up(stack_size, sizeof(u64)); | |
6488 | } | |
6489 | ||
6490 | return stack_size; | |
6491 | } | |
6492 | ||
6493 | static void | |
6494 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6495 | struct pt_regs *regs) | |
6496 | { | |
6497 | /* Case of a kernel thread, nothing to dump */ | |
6498 | if (!regs) { | |
6499 | u64 size = 0; | |
6500 | perf_output_put(handle, size); | |
6501 | } else { | |
6502 | unsigned long sp; | |
6503 | unsigned int rem; | |
6504 | u64 dyn_size; | |
02e18447 | 6505 | mm_segment_t fs; |
c5ebcedb JO |
6506 | |
6507 | /* | |
6508 | * We dump: | |
6509 | * static size | |
6510 | * - the size requested by user or the best one we can fit | |
6511 | * in to the sample max size | |
6512 | * data | |
6513 | * - user stack dump data | |
6514 | * dynamic size | |
6515 | * - the actual dumped size | |
6516 | */ | |
6517 | ||
6518 | /* Static size. */ | |
6519 | perf_output_put(handle, dump_size); | |
6520 | ||
6521 | /* Data. */ | |
6522 | sp = perf_user_stack_pointer(regs); | |
3d13f313 | 6523 | fs = force_uaccess_begin(); |
c5ebcedb | 6524 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
3d13f313 | 6525 | force_uaccess_end(fs); |
c5ebcedb JO |
6526 | dyn_size = dump_size - rem; |
6527 | ||
6528 | perf_output_skip(handle, rem); | |
6529 | ||
6530 | /* Dynamic size. */ | |
6531 | perf_output_put(handle, dyn_size); | |
6532 | } | |
6533 | } | |
6534 | ||
a4faf00d AS |
6535 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6536 | struct perf_sample_data *data, | |
6537 | size_t size) | |
6538 | { | |
6539 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6540 | struct perf_buffer *rb; |
a4faf00d AS |
6541 | |
6542 | data->aux_size = 0; | |
6543 | ||
6544 | if (!sampler) | |
6545 | goto out; | |
6546 | ||
6547 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6548 | goto out; | |
6549 | ||
6550 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6551 | goto out; | |
6552 | ||
6553 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6554 | if (!rb) | |
6555 | goto out; | |
6556 | ||
6557 | /* | |
6558 | * If this is an NMI hit inside sampling code, don't take | |
6559 | * the sample. See also perf_aux_sample_output(). | |
6560 | */ | |
6561 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6562 | data->aux_size = 0; | |
6563 | } else { | |
6564 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6565 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6566 | } | |
6567 | ring_buffer_put(rb); | |
6568 | ||
6569 | out: | |
6570 | return data->aux_size; | |
6571 | } | |
6572 | ||
56de4e8f | 6573 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6574 | struct perf_event *event, |
6575 | struct perf_output_handle *handle, | |
6576 | unsigned long size) | |
6577 | { | |
6578 | unsigned long flags; | |
6579 | long ret; | |
6580 | ||
6581 | /* | |
6582 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6583 | * paths. If we start calling them in NMI context, they may race with | |
6584 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6585 | * been stopped, which is why we're using a separate callback that | |
6586 | * doesn't change the event state. | |
6587 | * | |
6588 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6589 | */ | |
6590 | local_irq_save(flags); | |
6591 | /* | |
6592 | * Guard against NMI hits inside the critical section; | |
6593 | * see also perf_prepare_sample_aux(). | |
6594 | */ | |
6595 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6596 | barrier(); | |
6597 | ||
6598 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6599 | ||
6600 | barrier(); | |
6601 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6602 | local_irq_restore(flags); | |
6603 | ||
6604 | return ret; | |
6605 | } | |
6606 | ||
6607 | static void perf_aux_sample_output(struct perf_event *event, | |
6608 | struct perf_output_handle *handle, | |
6609 | struct perf_sample_data *data) | |
6610 | { | |
6611 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6612 | struct perf_buffer *rb; |
a4faf00d | 6613 | unsigned long pad; |
a4faf00d AS |
6614 | long size; |
6615 | ||
6616 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6617 | return; | |
6618 | ||
6619 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6620 | if (!rb) | |
6621 | return; | |
6622 | ||
6623 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6624 | ||
6625 | /* | |
6626 | * An error here means that perf_output_copy() failed (returned a | |
6627 | * non-zero surplus that it didn't copy), which in its current | |
6628 | * enlightened implementation is not possible. If that changes, we'd | |
6629 | * like to know. | |
6630 | */ | |
6631 | if (WARN_ON_ONCE(size < 0)) | |
6632 | goto out_put; | |
6633 | ||
6634 | /* | |
6635 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6636 | * perf_prepare_sample_aux(), so should not be more than that. | |
6637 | */ | |
6638 | pad = data->aux_size - size; | |
6639 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6640 | pad = 8; | |
6641 | ||
6642 | if (pad) { | |
6643 | u64 zero = 0; | |
6644 | perf_output_copy(handle, &zero, pad); | |
6645 | } | |
6646 | ||
6647 | out_put: | |
6648 | ring_buffer_put(rb); | |
6649 | } | |
6650 | ||
c980d109 ACM |
6651 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6652 | struct perf_sample_data *data, | |
6653 | struct perf_event *event) | |
6844c09d ACM |
6654 | { |
6655 | u64 sample_type = event->attr.sample_type; | |
6656 | ||
6657 | data->type = sample_type; | |
6658 | header->size += event->id_header_size; | |
6659 | ||
6660 | if (sample_type & PERF_SAMPLE_TID) { | |
6661 | /* namespace issues */ | |
6662 | data->tid_entry.pid = perf_event_pid(event, current); | |
6663 | data->tid_entry.tid = perf_event_tid(event, current); | |
6664 | } | |
6665 | ||
6666 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6667 | data->time = perf_event_clock(event); |
6844c09d | 6668 | |
ff3d527c | 6669 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6670 | data->id = primary_event_id(event); |
6671 | ||
6672 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6673 | data->stream_id = event->id; | |
6674 | ||
6675 | if (sample_type & PERF_SAMPLE_CPU) { | |
6676 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6677 | data->cpu_entry.reserved = 0; | |
6678 | } | |
6679 | } | |
6680 | ||
76369139 FW |
6681 | void perf_event_header__init_id(struct perf_event_header *header, |
6682 | struct perf_sample_data *data, | |
6683 | struct perf_event *event) | |
c980d109 ACM |
6684 | { |
6685 | if (event->attr.sample_id_all) | |
6686 | __perf_event_header__init_id(header, data, event); | |
6687 | } | |
6688 | ||
6689 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6690 | struct perf_sample_data *data) | |
6691 | { | |
6692 | u64 sample_type = data->type; | |
6693 | ||
6694 | if (sample_type & PERF_SAMPLE_TID) | |
6695 | perf_output_put(handle, data->tid_entry); | |
6696 | ||
6697 | if (sample_type & PERF_SAMPLE_TIME) | |
6698 | perf_output_put(handle, data->time); | |
6699 | ||
6700 | if (sample_type & PERF_SAMPLE_ID) | |
6701 | perf_output_put(handle, data->id); | |
6702 | ||
6703 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6704 | perf_output_put(handle, data->stream_id); | |
6705 | ||
6706 | if (sample_type & PERF_SAMPLE_CPU) | |
6707 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6708 | |
6709 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6710 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6711 | } |
6712 | ||
76369139 FW |
6713 | void perf_event__output_id_sample(struct perf_event *event, |
6714 | struct perf_output_handle *handle, | |
6715 | struct perf_sample_data *sample) | |
c980d109 ACM |
6716 | { |
6717 | if (event->attr.sample_id_all) | |
6718 | __perf_event__output_id_sample(handle, sample); | |
6719 | } | |
6720 | ||
3dab77fb | 6721 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6722 | struct perf_event *event, |
6723 | u64 enabled, u64 running) | |
3dab77fb | 6724 | { |
cdd6c482 | 6725 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6726 | u64 values[4]; |
6727 | int n = 0; | |
6728 | ||
b5e58793 | 6729 | values[n++] = perf_event_count(event); |
3dab77fb | 6730 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6731 | values[n++] = enabled + |
cdd6c482 | 6732 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6733 | } |
6734 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6735 | values[n++] = running + |
cdd6c482 | 6736 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6737 | } |
6738 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6739 | values[n++] = primary_event_id(event); |
3dab77fb | 6740 | |
76369139 | 6741 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6742 | } |
6743 | ||
3dab77fb | 6744 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6745 | struct perf_event *event, |
6746 | u64 enabled, u64 running) | |
3dab77fb | 6747 | { |
cdd6c482 IM |
6748 | struct perf_event *leader = event->group_leader, *sub; |
6749 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6750 | u64 values[5]; |
6751 | int n = 0; | |
6752 | ||
6753 | values[n++] = 1 + leader->nr_siblings; | |
6754 | ||
6755 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6756 | values[n++] = enabled; |
3dab77fb PZ |
6757 | |
6758 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6759 | values[n++] = running; |
3dab77fb | 6760 | |
9e5b127d PZ |
6761 | if ((leader != event) && |
6762 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6763 | leader->pmu->read(leader); |
6764 | ||
b5e58793 | 6765 | values[n++] = perf_event_count(leader); |
3dab77fb | 6766 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6767 | values[n++] = primary_event_id(leader); |
3dab77fb | 6768 | |
76369139 | 6769 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6770 | |
edb39592 | 6771 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6772 | n = 0; |
6773 | ||
6f5ab001 JO |
6774 | if ((sub != event) && |
6775 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6776 | sub->pmu->read(sub); |
6777 | ||
b5e58793 | 6778 | values[n++] = perf_event_count(sub); |
3dab77fb | 6779 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6780 | values[n++] = primary_event_id(sub); |
3dab77fb | 6781 | |
76369139 | 6782 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6783 | } |
6784 | } | |
6785 | ||
eed01528 SE |
6786 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6787 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6788 | ||
ba5213ae PZ |
6789 | /* |
6790 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6791 | * | |
6792 | * The problem is that its both hard and excessively expensive to iterate the | |
6793 | * child list, not to mention that its impossible to IPI the children running | |
6794 | * on another CPU, from interrupt/NMI context. | |
6795 | */ | |
3dab77fb | 6796 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6797 | struct perf_event *event) |
3dab77fb | 6798 | { |
e3f3541c | 6799 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6800 | u64 read_format = event->attr.read_format; |
6801 | ||
6802 | /* | |
6803 | * compute total_time_enabled, total_time_running | |
6804 | * based on snapshot values taken when the event | |
6805 | * was last scheduled in. | |
6806 | * | |
6807 | * we cannot simply called update_context_time() | |
6808 | * because of locking issue as we are called in | |
6809 | * NMI context | |
6810 | */ | |
c4794295 | 6811 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6812 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6813 | |
cdd6c482 | 6814 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6815 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6816 | else |
eed01528 | 6817 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6818 | } |
6819 | ||
bbfd5e4f KL |
6820 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6821 | { | |
6822 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6823 | } | |
6824 | ||
5622f295 MM |
6825 | void perf_output_sample(struct perf_output_handle *handle, |
6826 | struct perf_event_header *header, | |
6827 | struct perf_sample_data *data, | |
cdd6c482 | 6828 | struct perf_event *event) |
5622f295 MM |
6829 | { |
6830 | u64 sample_type = data->type; | |
6831 | ||
6832 | perf_output_put(handle, *header); | |
6833 | ||
ff3d527c AH |
6834 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6835 | perf_output_put(handle, data->id); | |
6836 | ||
5622f295 MM |
6837 | if (sample_type & PERF_SAMPLE_IP) |
6838 | perf_output_put(handle, data->ip); | |
6839 | ||
6840 | if (sample_type & PERF_SAMPLE_TID) | |
6841 | perf_output_put(handle, data->tid_entry); | |
6842 | ||
6843 | if (sample_type & PERF_SAMPLE_TIME) | |
6844 | perf_output_put(handle, data->time); | |
6845 | ||
6846 | if (sample_type & PERF_SAMPLE_ADDR) | |
6847 | perf_output_put(handle, data->addr); | |
6848 | ||
6849 | if (sample_type & PERF_SAMPLE_ID) | |
6850 | perf_output_put(handle, data->id); | |
6851 | ||
6852 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6853 | perf_output_put(handle, data->stream_id); | |
6854 | ||
6855 | if (sample_type & PERF_SAMPLE_CPU) | |
6856 | perf_output_put(handle, data->cpu_entry); | |
6857 | ||
6858 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6859 | perf_output_put(handle, data->period); | |
6860 | ||
6861 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6862 | perf_output_read(handle, event); |
5622f295 MM |
6863 | |
6864 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6865 | int size = 1; |
5622f295 | 6866 | |
99e818cc JO |
6867 | size += data->callchain->nr; |
6868 | size *= sizeof(u64); | |
6869 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6870 | } |
6871 | ||
6872 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6873 | struct perf_raw_record *raw = data->raw; |
6874 | ||
6875 | if (raw) { | |
6876 | struct perf_raw_frag *frag = &raw->frag; | |
6877 | ||
6878 | perf_output_put(handle, raw->size); | |
6879 | do { | |
6880 | if (frag->copy) { | |
6881 | __output_custom(handle, frag->copy, | |
6882 | frag->data, frag->size); | |
6883 | } else { | |
6884 | __output_copy(handle, frag->data, | |
6885 | frag->size); | |
6886 | } | |
6887 | if (perf_raw_frag_last(frag)) | |
6888 | break; | |
6889 | frag = frag->next; | |
6890 | } while (1); | |
6891 | if (frag->pad) | |
6892 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6893 | } else { |
6894 | struct { | |
6895 | u32 size; | |
6896 | u32 data; | |
6897 | } raw = { | |
6898 | .size = sizeof(u32), | |
6899 | .data = 0, | |
6900 | }; | |
6901 | perf_output_put(handle, raw); | |
6902 | } | |
6903 | } | |
a7ac67ea | 6904 | |
bce38cd5 SE |
6905 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6906 | if (data->br_stack) { | |
6907 | size_t size; | |
6908 | ||
6909 | size = data->br_stack->nr | |
6910 | * sizeof(struct perf_branch_entry); | |
6911 | ||
6912 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6913 | if (perf_sample_save_hw_index(event)) |
6914 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6915 | perf_output_copy(handle, data->br_stack->entries, size); |
6916 | } else { | |
6917 | /* | |
6918 | * we always store at least the value of nr | |
6919 | */ | |
6920 | u64 nr = 0; | |
6921 | perf_output_put(handle, nr); | |
6922 | } | |
6923 | } | |
4018994f JO |
6924 | |
6925 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6926 | u64 abi = data->regs_user.abi; | |
6927 | ||
6928 | /* | |
6929 | * If there are no regs to dump, notice it through | |
6930 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6931 | */ | |
6932 | perf_output_put(handle, abi); | |
6933 | ||
6934 | if (abi) { | |
6935 | u64 mask = event->attr.sample_regs_user; | |
6936 | perf_output_sample_regs(handle, | |
6937 | data->regs_user.regs, | |
6938 | mask); | |
6939 | } | |
6940 | } | |
c5ebcedb | 6941 | |
a5cdd40c | 6942 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6943 | perf_output_sample_ustack(handle, |
6944 | data->stack_user_size, | |
6945 | data->regs_user.regs); | |
a5cdd40c | 6946 | } |
c3feedf2 AK |
6947 | |
6948 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6949 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6950 | |
6951 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6952 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6953 | |
fdfbbd07 AK |
6954 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6955 | perf_output_put(handle, data->txn); | |
6956 | ||
60e2364e SE |
6957 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6958 | u64 abi = data->regs_intr.abi; | |
6959 | /* | |
6960 | * If there are no regs to dump, notice it through | |
6961 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6962 | */ | |
6963 | perf_output_put(handle, abi); | |
6964 | ||
6965 | if (abi) { | |
6966 | u64 mask = event->attr.sample_regs_intr; | |
6967 | ||
6968 | perf_output_sample_regs(handle, | |
6969 | data->regs_intr.regs, | |
6970 | mask); | |
6971 | } | |
6972 | } | |
6973 | ||
fc7ce9c7 KL |
6974 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6975 | perf_output_put(handle, data->phys_addr); | |
6976 | ||
6546b19f NK |
6977 | if (sample_type & PERF_SAMPLE_CGROUP) |
6978 | perf_output_put(handle, data->cgroup); | |
6979 | ||
8d97e718 KL |
6980 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
6981 | perf_output_put(handle, data->data_page_size); | |
6982 | ||
995f088e SE |
6983 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
6984 | perf_output_put(handle, data->code_page_size); | |
6985 | ||
a4faf00d AS |
6986 | if (sample_type & PERF_SAMPLE_AUX) { |
6987 | perf_output_put(handle, data->aux_size); | |
6988 | ||
6989 | if (data->aux_size) | |
6990 | perf_aux_sample_output(event, handle, data); | |
6991 | } | |
6992 | ||
a5cdd40c PZ |
6993 | if (!event->attr.watermark) { |
6994 | int wakeup_events = event->attr.wakeup_events; | |
6995 | ||
6996 | if (wakeup_events) { | |
56de4e8f | 6997 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6998 | int events = local_inc_return(&rb->events); |
6999 | ||
7000 | if (events >= wakeup_events) { | |
7001 | local_sub(wakeup_events, &rb->events); | |
7002 | local_inc(&rb->wakeup); | |
7003 | } | |
7004 | } | |
7005 | } | |
5622f295 MM |
7006 | } |
7007 | ||
fc7ce9c7 KL |
7008 | static u64 perf_virt_to_phys(u64 virt) |
7009 | { | |
7010 | u64 phys_addr = 0; | |
7011 | struct page *p = NULL; | |
7012 | ||
7013 | if (!virt) | |
7014 | return 0; | |
7015 | ||
7016 | if (virt >= TASK_SIZE) { | |
7017 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
7018 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
7019 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
7020 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
7021 | } else { | |
7022 | /* | |
7023 | * Walking the pages tables for user address. | |
7024 | * Interrupts are disabled, so it prevents any tear down | |
7025 | * of the page tables. | |
dadbb612 | 7026 | * Try IRQ-safe get_user_page_fast_only first. |
fc7ce9c7 KL |
7027 | * If failed, leave phys_addr as 0. |
7028 | */ | |
d3296fb3 JO |
7029 | if (current->mm != NULL) { |
7030 | pagefault_disable(); | |
dadbb612 | 7031 | if (get_user_page_fast_only(virt, 0, &p)) |
d3296fb3 JO |
7032 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; |
7033 | pagefault_enable(); | |
7034 | } | |
fc7ce9c7 KL |
7035 | |
7036 | if (p) | |
7037 | put_page(p); | |
7038 | } | |
7039 | ||
7040 | return phys_addr; | |
7041 | } | |
7042 | ||
8d97e718 | 7043 | /* |
8af26be0 | 7044 | * Return the pagetable size of a given virtual address. |
8d97e718 | 7045 | */ |
8af26be0 | 7046 | static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) |
8d97e718 | 7047 | { |
8af26be0 | 7048 | u64 size = 0; |
8d97e718 | 7049 | |
8af26be0 PZ |
7050 | #ifdef CONFIG_HAVE_FAST_GUP |
7051 | pgd_t *pgdp, pgd; | |
7052 | p4d_t *p4dp, p4d; | |
7053 | pud_t *pudp, pud; | |
7054 | pmd_t *pmdp, pmd; | |
7055 | pte_t *ptep, pte; | |
8d97e718 | 7056 | |
8af26be0 PZ |
7057 | pgdp = pgd_offset(mm, addr); |
7058 | pgd = READ_ONCE(*pgdp); | |
7059 | if (pgd_none(pgd)) | |
8d97e718 KL |
7060 | return 0; |
7061 | ||
8af26be0 PZ |
7062 | if (pgd_leaf(pgd)) |
7063 | return pgd_leaf_size(pgd); | |
8d97e718 | 7064 | |
8af26be0 PZ |
7065 | p4dp = p4d_offset_lockless(pgdp, pgd, addr); |
7066 | p4d = READ_ONCE(*p4dp); | |
7067 | if (!p4d_present(p4d)) | |
8d97e718 KL |
7068 | return 0; |
7069 | ||
8af26be0 PZ |
7070 | if (p4d_leaf(p4d)) |
7071 | return p4d_leaf_size(p4d); | |
8d97e718 | 7072 | |
8af26be0 PZ |
7073 | pudp = pud_offset_lockless(p4dp, p4d, addr); |
7074 | pud = READ_ONCE(*pudp); | |
7075 | if (!pud_present(pud)) | |
8d97e718 KL |
7076 | return 0; |
7077 | ||
8af26be0 PZ |
7078 | if (pud_leaf(pud)) |
7079 | return pud_leaf_size(pud); | |
8d97e718 | 7080 | |
8af26be0 PZ |
7081 | pmdp = pmd_offset_lockless(pudp, pud, addr); |
7082 | pmd = READ_ONCE(*pmdp); | |
7083 | if (!pmd_present(pmd)) | |
8d97e718 | 7084 | return 0; |
8d97e718 | 7085 | |
8af26be0 PZ |
7086 | if (pmd_leaf(pmd)) |
7087 | return pmd_leaf_size(pmd); | |
51b646b2 | 7088 | |
8af26be0 PZ |
7089 | ptep = pte_offset_map(&pmd, addr); |
7090 | pte = ptep_get_lockless(ptep); | |
7091 | if (pte_present(pte)) | |
7092 | size = pte_leaf_size(pte); | |
7093 | pte_unmap(ptep); | |
7094 | #endif /* CONFIG_HAVE_FAST_GUP */ | |
8d97e718 | 7095 | |
8af26be0 | 7096 | return size; |
8d97e718 KL |
7097 | } |
7098 | ||
8d97e718 KL |
7099 | static u64 perf_get_page_size(unsigned long addr) |
7100 | { | |
7101 | struct mm_struct *mm; | |
7102 | unsigned long flags; | |
7103 | u64 size; | |
7104 | ||
7105 | if (!addr) | |
7106 | return 0; | |
7107 | ||
7108 | /* | |
7109 | * Software page-table walkers must disable IRQs, | |
7110 | * which prevents any tear down of the page tables. | |
7111 | */ | |
7112 | local_irq_save(flags); | |
7113 | ||
7114 | mm = current->mm; | |
7115 | if (!mm) { | |
7116 | /* | |
7117 | * For kernel threads and the like, use init_mm so that | |
7118 | * we can find kernel memory. | |
7119 | */ | |
7120 | mm = &init_mm; | |
7121 | } | |
7122 | ||
8af26be0 | 7123 | size = perf_get_pgtable_size(mm, addr); |
8d97e718 KL |
7124 | |
7125 | local_irq_restore(flags); | |
7126 | ||
7127 | return size; | |
7128 | } | |
7129 | ||
99e818cc JO |
7130 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
7131 | ||
6cbc304f | 7132 | struct perf_callchain_entry * |
8cf7e0e2 JO |
7133 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
7134 | { | |
7135 | bool kernel = !event->attr.exclude_callchain_kernel; | |
7136 | bool user = !event->attr.exclude_callchain_user; | |
7137 | /* Disallow cross-task user callchains. */ | |
7138 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
7139 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 7140 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
7141 | |
7142 | if (!kernel && !user) | |
99e818cc | 7143 | return &__empty_callchain; |
8cf7e0e2 | 7144 | |
99e818cc JO |
7145 | callchain = get_perf_callchain(regs, 0, kernel, user, |
7146 | max_stack, crosstask, true); | |
7147 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
7148 | } |
7149 | ||
5622f295 MM |
7150 | void perf_prepare_sample(struct perf_event_header *header, |
7151 | struct perf_sample_data *data, | |
cdd6c482 | 7152 | struct perf_event *event, |
5622f295 | 7153 | struct pt_regs *regs) |
7b732a75 | 7154 | { |
cdd6c482 | 7155 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 7156 | |
cdd6c482 | 7157 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 7158 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
7159 | |
7160 | header->misc = 0; | |
7161 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 7162 | |
c980d109 | 7163 | __perf_event_header__init_id(header, data, event); |
6844c09d | 7164 | |
995f088e | 7165 | if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE)) |
5622f295 MM |
7166 | data->ip = perf_instruction_pointer(regs); |
7167 | ||
b23f3325 | 7168 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 7169 | int size = 1; |
394ee076 | 7170 | |
6cbc304f PZ |
7171 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
7172 | data->callchain = perf_callchain(event, regs); | |
7173 | ||
99e818cc | 7174 | size += data->callchain->nr; |
5622f295 MM |
7175 | |
7176 | header->size += size * sizeof(u64); | |
394ee076 PZ |
7177 | } |
7178 | ||
3a43ce68 | 7179 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
7180 | struct perf_raw_record *raw = data->raw; |
7181 | int size; | |
7182 | ||
7183 | if (raw) { | |
7184 | struct perf_raw_frag *frag = &raw->frag; | |
7185 | u32 sum = 0; | |
7186 | ||
7187 | do { | |
7188 | sum += frag->size; | |
7189 | if (perf_raw_frag_last(frag)) | |
7190 | break; | |
7191 | frag = frag->next; | |
7192 | } while (1); | |
7193 | ||
7194 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
7195 | raw->size = size - sizeof(u32); | |
7196 | frag->pad = raw->size - sum; | |
7197 | } else { | |
7198 | size = sizeof(u64); | |
7199 | } | |
a044560c | 7200 | |
7e3f977e | 7201 | header->size += size; |
7f453c24 | 7202 | } |
bce38cd5 SE |
7203 | |
7204 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7205 | int size = sizeof(u64); /* nr */ | |
7206 | if (data->br_stack) { | |
bbfd5e4f KL |
7207 | if (perf_sample_save_hw_index(event)) |
7208 | size += sizeof(u64); | |
7209 | ||
bce38cd5 SE |
7210 | size += data->br_stack->nr |
7211 | * sizeof(struct perf_branch_entry); | |
7212 | } | |
7213 | header->size += size; | |
7214 | } | |
4018994f | 7215 | |
2565711f | 7216 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
76a4efa8 | 7217 | perf_sample_regs_user(&data->regs_user, regs); |
2565711f | 7218 | |
4018994f JO |
7219 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7220 | /* regs dump ABI info */ | |
7221 | int size = sizeof(u64); | |
7222 | ||
4018994f JO |
7223 | if (data->regs_user.regs) { |
7224 | u64 mask = event->attr.sample_regs_user; | |
7225 | size += hweight64(mask) * sizeof(u64); | |
7226 | } | |
7227 | ||
7228 | header->size += size; | |
7229 | } | |
c5ebcedb JO |
7230 | |
7231 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7232 | /* | |
9f014e3a | 7233 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7234 | * processed as the last one or have additional check added |
7235 | * in case new sample type is added, because we could eat | |
7236 | * up the rest of the sample size. | |
7237 | */ | |
c5ebcedb JO |
7238 | u16 stack_size = event->attr.sample_stack_user; |
7239 | u16 size = sizeof(u64); | |
7240 | ||
c5ebcedb | 7241 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7242 | data->regs_user.regs); |
c5ebcedb JO |
7243 | |
7244 | /* | |
7245 | * If there is something to dump, add space for the dump | |
7246 | * itself and for the field that tells the dynamic size, | |
7247 | * which is how many have been actually dumped. | |
7248 | */ | |
7249 | if (stack_size) | |
7250 | size += sizeof(u64) + stack_size; | |
7251 | ||
7252 | data->stack_user_size = stack_size; | |
7253 | header->size += size; | |
7254 | } | |
60e2364e SE |
7255 | |
7256 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7257 | /* regs dump ABI info */ | |
7258 | int size = sizeof(u64); | |
7259 | ||
7260 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7261 | ||
7262 | if (data->regs_intr.regs) { | |
7263 | u64 mask = event->attr.sample_regs_intr; | |
7264 | ||
7265 | size += hweight64(mask) * sizeof(u64); | |
7266 | } | |
7267 | ||
7268 | header->size += size; | |
7269 | } | |
fc7ce9c7 KL |
7270 | |
7271 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7272 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7273 | |
6546b19f NK |
7274 | #ifdef CONFIG_CGROUP_PERF |
7275 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7276 | struct cgroup *cgrp; | |
7277 | ||
7278 | /* protected by RCU */ | |
7279 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7280 | data->cgroup = cgroup_id(cgrp); | |
7281 | } | |
7282 | #endif | |
7283 | ||
8d97e718 KL |
7284 | /* |
7285 | * PERF_DATA_PAGE_SIZE requires PERF_SAMPLE_ADDR. If the user doesn't | |
7286 | * require PERF_SAMPLE_ADDR, kernel implicitly retrieve the data->addr, | |
7287 | * but the value will not dump to the userspace. | |
7288 | */ | |
7289 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) | |
7290 | data->data_page_size = perf_get_page_size(data->addr); | |
7291 | ||
995f088e SE |
7292 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7293 | data->code_page_size = perf_get_page_size(data->ip); | |
7294 | ||
a4faf00d AS |
7295 | if (sample_type & PERF_SAMPLE_AUX) { |
7296 | u64 size; | |
7297 | ||
7298 | header->size += sizeof(u64); /* size */ | |
7299 | ||
7300 | /* | |
7301 | * Given the 16bit nature of header::size, an AUX sample can | |
7302 | * easily overflow it, what with all the preceding sample bits. | |
7303 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7304 | * per sample in total (rounded down to 8 byte boundary). | |
7305 | */ | |
7306 | size = min_t(size_t, U16_MAX - header->size, | |
7307 | event->attr.aux_sample_size); | |
7308 | size = rounddown(size, 8); | |
7309 | size = perf_prepare_sample_aux(event, data, size); | |
7310 | ||
7311 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7312 | header->size += size; | |
7313 | } | |
7314 | /* | |
7315 | * If you're adding more sample types here, you likely need to do | |
7316 | * something about the overflowing header::size, like repurpose the | |
7317 | * lowest 3 bits of size, which should be always zero at the moment. | |
7318 | * This raises a more important question, do we really need 512k sized | |
7319 | * samples and why, so good argumentation is in order for whatever you | |
7320 | * do here next. | |
7321 | */ | |
7322 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7323 | } |
7f453c24 | 7324 | |
56201969 | 7325 | static __always_inline int |
9ecda41a WN |
7326 | __perf_event_output(struct perf_event *event, |
7327 | struct perf_sample_data *data, | |
7328 | struct pt_regs *regs, | |
7329 | int (*output_begin)(struct perf_output_handle *, | |
267fb273 | 7330 | struct perf_sample_data *, |
9ecda41a WN |
7331 | struct perf_event *, |
7332 | unsigned int)) | |
5622f295 MM |
7333 | { |
7334 | struct perf_output_handle handle; | |
7335 | struct perf_event_header header; | |
56201969 | 7336 | int err; |
689802b2 | 7337 | |
927c7a9e FW |
7338 | /* protect the callchain buffers */ |
7339 | rcu_read_lock(); | |
7340 | ||
cdd6c482 | 7341 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7342 | |
267fb273 | 7343 | err = output_begin(&handle, data, event, header.size); |
56201969 | 7344 | if (err) |
927c7a9e | 7345 | goto exit; |
0322cd6e | 7346 | |
cdd6c482 | 7347 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7348 | |
8a057d84 | 7349 | perf_output_end(&handle); |
927c7a9e FW |
7350 | |
7351 | exit: | |
7352 | rcu_read_unlock(); | |
56201969 | 7353 | return err; |
0322cd6e PZ |
7354 | } |
7355 | ||
9ecda41a WN |
7356 | void |
7357 | perf_event_output_forward(struct perf_event *event, | |
7358 | struct perf_sample_data *data, | |
7359 | struct pt_regs *regs) | |
7360 | { | |
7361 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7362 | } | |
7363 | ||
7364 | void | |
7365 | perf_event_output_backward(struct perf_event *event, | |
7366 | struct perf_sample_data *data, | |
7367 | struct pt_regs *regs) | |
7368 | { | |
7369 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7370 | } | |
7371 | ||
56201969 | 7372 | int |
9ecda41a WN |
7373 | perf_event_output(struct perf_event *event, |
7374 | struct perf_sample_data *data, | |
7375 | struct pt_regs *regs) | |
7376 | { | |
56201969 | 7377 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7378 | } |
7379 | ||
38b200d6 | 7380 | /* |
cdd6c482 | 7381 | * read event_id |
38b200d6 PZ |
7382 | */ |
7383 | ||
7384 | struct perf_read_event { | |
7385 | struct perf_event_header header; | |
7386 | ||
7387 | u32 pid; | |
7388 | u32 tid; | |
38b200d6 PZ |
7389 | }; |
7390 | ||
7391 | static void | |
cdd6c482 | 7392 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7393 | struct task_struct *task) |
7394 | { | |
7395 | struct perf_output_handle handle; | |
c980d109 | 7396 | struct perf_sample_data sample; |
dfc65094 | 7397 | struct perf_read_event read_event = { |
38b200d6 | 7398 | .header = { |
cdd6c482 | 7399 | .type = PERF_RECORD_READ, |
38b200d6 | 7400 | .misc = 0, |
c320c7b7 | 7401 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7402 | }, |
cdd6c482 IM |
7403 | .pid = perf_event_pid(event, task), |
7404 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7405 | }; |
3dab77fb | 7406 | int ret; |
38b200d6 | 7407 | |
c980d109 | 7408 | perf_event_header__init_id(&read_event.header, &sample, event); |
267fb273 | 7409 | ret = perf_output_begin(&handle, &sample, event, read_event.header.size); |
38b200d6 PZ |
7410 | if (ret) |
7411 | return; | |
7412 | ||
dfc65094 | 7413 | perf_output_put(&handle, read_event); |
cdd6c482 | 7414 | perf_output_read(&handle, event); |
c980d109 | 7415 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7416 | |
38b200d6 PZ |
7417 | perf_output_end(&handle); |
7418 | } | |
7419 | ||
aab5b71e | 7420 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7421 | |
7422 | static void | |
aab5b71e PZ |
7423 | perf_iterate_ctx(struct perf_event_context *ctx, |
7424 | perf_iterate_f output, | |
b73e4fef | 7425 | void *data, bool all) |
52d857a8 JO |
7426 | { |
7427 | struct perf_event *event; | |
7428 | ||
7429 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7430 | if (!all) { |
7431 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7432 | continue; | |
7433 | if (!event_filter_match(event)) | |
7434 | continue; | |
7435 | } | |
7436 | ||
67516844 | 7437 | output(event, data); |
52d857a8 JO |
7438 | } |
7439 | } | |
7440 | ||
aab5b71e | 7441 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7442 | { |
7443 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7444 | struct perf_event *event; | |
7445 | ||
7446 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7447 | /* |
7448 | * Skip events that are not fully formed yet; ensure that | |
7449 | * if we observe event->ctx, both event and ctx will be | |
7450 | * complete enough. See perf_install_in_context(). | |
7451 | */ | |
7452 | if (!smp_load_acquire(&event->ctx)) | |
7453 | continue; | |
7454 | ||
f2fb6bef KL |
7455 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7456 | continue; | |
7457 | if (!event_filter_match(event)) | |
7458 | continue; | |
7459 | output(event, data); | |
7460 | } | |
7461 | } | |
7462 | ||
aab5b71e PZ |
7463 | /* |
7464 | * Iterate all events that need to receive side-band events. | |
7465 | * | |
7466 | * For new callers; ensure that account_pmu_sb_event() includes | |
7467 | * your event, otherwise it might not get delivered. | |
7468 | */ | |
52d857a8 | 7469 | static void |
aab5b71e | 7470 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7471 | struct perf_event_context *task_ctx) |
7472 | { | |
52d857a8 | 7473 | struct perf_event_context *ctx; |
52d857a8 JO |
7474 | int ctxn; |
7475 | ||
aab5b71e PZ |
7476 | rcu_read_lock(); |
7477 | preempt_disable(); | |
7478 | ||
4e93ad60 | 7479 | /* |
aab5b71e PZ |
7480 | * If we have task_ctx != NULL we only notify the task context itself. |
7481 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7482 | * context. |
7483 | */ | |
7484 | if (task_ctx) { | |
aab5b71e PZ |
7485 | perf_iterate_ctx(task_ctx, output, data, false); |
7486 | goto done; | |
4e93ad60 JO |
7487 | } |
7488 | ||
aab5b71e | 7489 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7490 | |
7491 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7492 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7493 | if (ctx) | |
aab5b71e | 7494 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7495 | } |
aab5b71e | 7496 | done: |
f2fb6bef | 7497 | preempt_enable(); |
52d857a8 | 7498 | rcu_read_unlock(); |
95ff4ca2 AS |
7499 | } |
7500 | ||
375637bc AS |
7501 | /* |
7502 | * Clear all file-based filters at exec, they'll have to be | |
7503 | * re-instated when/if these objects are mmapped again. | |
7504 | */ | |
7505 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7506 | { | |
7507 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7508 | struct perf_addr_filter *filter; | |
7509 | unsigned int restart = 0, count = 0; | |
7510 | unsigned long flags; | |
7511 | ||
7512 | if (!has_addr_filter(event)) | |
7513 | return; | |
7514 | ||
7515 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7516 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7517 | if (filter->path.dentry) { |
c60f83b8 AS |
7518 | event->addr_filter_ranges[count].start = 0; |
7519 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7520 | restart++; |
7521 | } | |
7522 | ||
7523 | count++; | |
7524 | } | |
7525 | ||
7526 | if (restart) | |
7527 | event->addr_filters_gen++; | |
7528 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7529 | ||
7530 | if (restart) | |
767ae086 | 7531 | perf_event_stop(event, 1); |
375637bc AS |
7532 | } |
7533 | ||
7534 | void perf_event_exec(void) | |
7535 | { | |
7536 | struct perf_event_context *ctx; | |
7537 | int ctxn; | |
7538 | ||
7539 | rcu_read_lock(); | |
7540 | for_each_task_context_nr(ctxn) { | |
7541 | ctx = current->perf_event_ctxp[ctxn]; | |
7542 | if (!ctx) | |
7543 | continue; | |
7544 | ||
7545 | perf_event_enable_on_exec(ctxn); | |
7546 | ||
aab5b71e | 7547 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7548 | true); |
7549 | } | |
7550 | rcu_read_unlock(); | |
7551 | } | |
7552 | ||
95ff4ca2 | 7553 | struct remote_output { |
56de4e8f | 7554 | struct perf_buffer *rb; |
95ff4ca2 AS |
7555 | int err; |
7556 | }; | |
7557 | ||
7558 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7559 | { | |
7560 | struct perf_event *parent = event->parent; | |
7561 | struct remote_output *ro = data; | |
56de4e8f | 7562 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7563 | struct stop_event_data sd = { |
7564 | .event = event, | |
7565 | }; | |
95ff4ca2 AS |
7566 | |
7567 | if (!has_aux(event)) | |
7568 | return; | |
7569 | ||
7570 | if (!parent) | |
7571 | parent = event; | |
7572 | ||
7573 | /* | |
7574 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7575 | * ring-buffer, but it will be the child that's actually using it. |
7576 | * | |
7577 | * We are using event::rb to determine if the event should be stopped, | |
7578 | * however this may race with ring_buffer_attach() (through set_output), | |
7579 | * which will make us skip the event that actually needs to be stopped. | |
7580 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7581 | * its rb pointer. | |
95ff4ca2 AS |
7582 | */ |
7583 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7584 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7585 | } |
7586 | ||
7587 | static int __perf_pmu_output_stop(void *info) | |
7588 | { | |
7589 | struct perf_event *event = info; | |
f3a519e4 | 7590 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7591 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7592 | struct remote_output ro = { |
7593 | .rb = event->rb, | |
7594 | }; | |
7595 | ||
7596 | rcu_read_lock(); | |
aab5b71e | 7597 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7598 | if (cpuctx->task_ctx) |
aab5b71e | 7599 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7600 | &ro, false); |
95ff4ca2 AS |
7601 | rcu_read_unlock(); |
7602 | ||
7603 | return ro.err; | |
7604 | } | |
7605 | ||
7606 | static void perf_pmu_output_stop(struct perf_event *event) | |
7607 | { | |
7608 | struct perf_event *iter; | |
7609 | int err, cpu; | |
7610 | ||
7611 | restart: | |
7612 | rcu_read_lock(); | |
7613 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7614 | /* | |
7615 | * For per-CPU events, we need to make sure that neither they | |
7616 | * nor their children are running; for cpu==-1 events it's | |
7617 | * sufficient to stop the event itself if it's active, since | |
7618 | * it can't have children. | |
7619 | */ | |
7620 | cpu = iter->cpu; | |
7621 | if (cpu == -1) | |
7622 | cpu = READ_ONCE(iter->oncpu); | |
7623 | ||
7624 | if (cpu == -1) | |
7625 | continue; | |
7626 | ||
7627 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7628 | if (err == -EAGAIN) { | |
7629 | rcu_read_unlock(); | |
7630 | goto restart; | |
7631 | } | |
7632 | } | |
7633 | rcu_read_unlock(); | |
52d857a8 JO |
7634 | } |
7635 | ||
60313ebe | 7636 | /* |
9f498cc5 PZ |
7637 | * task tracking -- fork/exit |
7638 | * | |
13d7a241 | 7639 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7640 | */ |
7641 | ||
9f498cc5 | 7642 | struct perf_task_event { |
3a80b4a3 | 7643 | struct task_struct *task; |
cdd6c482 | 7644 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7645 | |
7646 | struct { | |
7647 | struct perf_event_header header; | |
7648 | ||
7649 | u32 pid; | |
7650 | u32 ppid; | |
9f498cc5 PZ |
7651 | u32 tid; |
7652 | u32 ptid; | |
393b2ad8 | 7653 | u64 time; |
cdd6c482 | 7654 | } event_id; |
60313ebe PZ |
7655 | }; |
7656 | ||
67516844 JO |
7657 | static int perf_event_task_match(struct perf_event *event) |
7658 | { | |
13d7a241 SE |
7659 | return event->attr.comm || event->attr.mmap || |
7660 | event->attr.mmap2 || event->attr.mmap_data || | |
7661 | event->attr.task; | |
67516844 JO |
7662 | } |
7663 | ||
cdd6c482 | 7664 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7665 | void *data) |
60313ebe | 7666 | { |
52d857a8 | 7667 | struct perf_task_event *task_event = data; |
60313ebe | 7668 | struct perf_output_handle handle; |
c980d109 | 7669 | struct perf_sample_data sample; |
9f498cc5 | 7670 | struct task_struct *task = task_event->task; |
c980d109 | 7671 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7672 | |
67516844 JO |
7673 | if (!perf_event_task_match(event)) |
7674 | return; | |
7675 | ||
c980d109 | 7676 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7677 | |
267fb273 | 7678 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7679 | task_event->event_id.header.size); |
ef60777c | 7680 | if (ret) |
c980d109 | 7681 | goto out; |
60313ebe | 7682 | |
cdd6c482 | 7683 | task_event->event_id.pid = perf_event_pid(event, task); |
cdd6c482 | 7684 | task_event->event_id.tid = perf_event_tid(event, task); |
f3bed55e IR |
7685 | |
7686 | if (task_event->event_id.header.type == PERF_RECORD_EXIT) { | |
7687 | task_event->event_id.ppid = perf_event_pid(event, | |
7688 | task->real_parent); | |
7689 | task_event->event_id.ptid = perf_event_pid(event, | |
7690 | task->real_parent); | |
7691 | } else { /* PERF_RECORD_FORK */ | |
7692 | task_event->event_id.ppid = perf_event_pid(event, current); | |
7693 | task_event->event_id.ptid = perf_event_tid(event, current); | |
7694 | } | |
9f498cc5 | 7695 | |
34f43927 PZ |
7696 | task_event->event_id.time = perf_event_clock(event); |
7697 | ||
cdd6c482 | 7698 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7699 | |
c980d109 ACM |
7700 | perf_event__output_id_sample(event, &handle, &sample); |
7701 | ||
60313ebe | 7702 | perf_output_end(&handle); |
c980d109 ACM |
7703 | out: |
7704 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7705 | } |
7706 | ||
cdd6c482 IM |
7707 | static void perf_event_task(struct task_struct *task, |
7708 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7709 | int new) |
60313ebe | 7710 | { |
9f498cc5 | 7711 | struct perf_task_event task_event; |
60313ebe | 7712 | |
cdd6c482 IM |
7713 | if (!atomic_read(&nr_comm_events) && |
7714 | !atomic_read(&nr_mmap_events) && | |
7715 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7716 | return; |
7717 | ||
9f498cc5 | 7718 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7719 | .task = task, |
7720 | .task_ctx = task_ctx, | |
cdd6c482 | 7721 | .event_id = { |
60313ebe | 7722 | .header = { |
cdd6c482 | 7723 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7724 | .misc = 0, |
cdd6c482 | 7725 | .size = sizeof(task_event.event_id), |
60313ebe | 7726 | }, |
573402db PZ |
7727 | /* .pid */ |
7728 | /* .ppid */ | |
9f498cc5 PZ |
7729 | /* .tid */ |
7730 | /* .ptid */ | |
34f43927 | 7731 | /* .time */ |
60313ebe PZ |
7732 | }, |
7733 | }; | |
7734 | ||
aab5b71e | 7735 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7736 | &task_event, |
7737 | task_ctx); | |
9f498cc5 PZ |
7738 | } |
7739 | ||
cdd6c482 | 7740 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7741 | { |
cdd6c482 | 7742 | perf_event_task(task, NULL, 1); |
e4222673 | 7743 | perf_event_namespaces(task); |
60313ebe PZ |
7744 | } |
7745 | ||
8d1b2d93 PZ |
7746 | /* |
7747 | * comm tracking | |
7748 | */ | |
7749 | ||
7750 | struct perf_comm_event { | |
22a4f650 IM |
7751 | struct task_struct *task; |
7752 | char *comm; | |
8d1b2d93 PZ |
7753 | int comm_size; |
7754 | ||
7755 | struct { | |
7756 | struct perf_event_header header; | |
7757 | ||
7758 | u32 pid; | |
7759 | u32 tid; | |
cdd6c482 | 7760 | } event_id; |
8d1b2d93 PZ |
7761 | }; |
7762 | ||
67516844 JO |
7763 | static int perf_event_comm_match(struct perf_event *event) |
7764 | { | |
7765 | return event->attr.comm; | |
7766 | } | |
7767 | ||
cdd6c482 | 7768 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7769 | void *data) |
8d1b2d93 | 7770 | { |
52d857a8 | 7771 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7772 | struct perf_output_handle handle; |
c980d109 | 7773 | struct perf_sample_data sample; |
cdd6c482 | 7774 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7775 | int ret; |
7776 | ||
67516844 JO |
7777 | if (!perf_event_comm_match(event)) |
7778 | return; | |
7779 | ||
c980d109 | 7780 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
267fb273 | 7781 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7782 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7783 | |
7784 | if (ret) | |
c980d109 | 7785 | goto out; |
8d1b2d93 | 7786 | |
cdd6c482 IM |
7787 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7788 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7789 | |
cdd6c482 | 7790 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7791 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7792 | comm_event->comm_size); |
c980d109 ACM |
7793 | |
7794 | perf_event__output_id_sample(event, &handle, &sample); | |
7795 | ||
8d1b2d93 | 7796 | perf_output_end(&handle); |
c980d109 ACM |
7797 | out: |
7798 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7799 | } |
7800 | ||
cdd6c482 | 7801 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7802 | { |
413ee3b4 | 7803 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7804 | unsigned int size; |
8d1b2d93 | 7805 | |
413ee3b4 | 7806 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7807 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7808 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7809 | |
7810 | comm_event->comm = comm; | |
7811 | comm_event->comm_size = size; | |
7812 | ||
cdd6c482 | 7813 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7814 | |
aab5b71e | 7815 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7816 | comm_event, |
7817 | NULL); | |
8d1b2d93 PZ |
7818 | } |
7819 | ||
82b89778 | 7820 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7821 | { |
9ee318a7 PZ |
7822 | struct perf_comm_event comm_event; |
7823 | ||
cdd6c482 | 7824 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7825 | return; |
a63eaf34 | 7826 | |
9ee318a7 | 7827 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7828 | .task = task, |
573402db PZ |
7829 | /* .comm */ |
7830 | /* .comm_size */ | |
cdd6c482 | 7831 | .event_id = { |
573402db | 7832 | .header = { |
cdd6c482 | 7833 | .type = PERF_RECORD_COMM, |
82b89778 | 7834 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7835 | /* .size */ |
7836 | }, | |
7837 | /* .pid */ | |
7838 | /* .tid */ | |
8d1b2d93 PZ |
7839 | }, |
7840 | }; | |
7841 | ||
cdd6c482 | 7842 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7843 | } |
7844 | ||
e4222673 HB |
7845 | /* |
7846 | * namespaces tracking | |
7847 | */ | |
7848 | ||
7849 | struct perf_namespaces_event { | |
7850 | struct task_struct *task; | |
7851 | ||
7852 | struct { | |
7853 | struct perf_event_header header; | |
7854 | ||
7855 | u32 pid; | |
7856 | u32 tid; | |
7857 | u64 nr_namespaces; | |
7858 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7859 | } event_id; | |
7860 | }; | |
7861 | ||
7862 | static int perf_event_namespaces_match(struct perf_event *event) | |
7863 | { | |
7864 | return event->attr.namespaces; | |
7865 | } | |
7866 | ||
7867 | static void perf_event_namespaces_output(struct perf_event *event, | |
7868 | void *data) | |
7869 | { | |
7870 | struct perf_namespaces_event *namespaces_event = data; | |
7871 | struct perf_output_handle handle; | |
7872 | struct perf_sample_data sample; | |
34900ec5 | 7873 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7874 | int ret; |
7875 | ||
7876 | if (!perf_event_namespaces_match(event)) | |
7877 | return; | |
7878 | ||
7879 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7880 | &sample, event); | |
267fb273 | 7881 | ret = perf_output_begin(&handle, &sample, event, |
e4222673 HB |
7882 | namespaces_event->event_id.header.size); |
7883 | if (ret) | |
34900ec5 | 7884 | goto out; |
e4222673 HB |
7885 | |
7886 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7887 | namespaces_event->task); | |
7888 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7889 | namespaces_event->task); | |
7890 | ||
7891 | perf_output_put(&handle, namespaces_event->event_id); | |
7892 | ||
7893 | perf_event__output_id_sample(event, &handle, &sample); | |
7894 | ||
7895 | perf_output_end(&handle); | |
34900ec5 JO |
7896 | out: |
7897 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7898 | } |
7899 | ||
7900 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7901 | struct task_struct *task, | |
7902 | const struct proc_ns_operations *ns_ops) | |
7903 | { | |
7904 | struct path ns_path; | |
7905 | struct inode *ns_inode; | |
ce623f89 | 7906 | int error; |
e4222673 HB |
7907 | |
7908 | error = ns_get_path(&ns_path, task, ns_ops); | |
7909 | if (!error) { | |
7910 | ns_inode = ns_path.dentry->d_inode; | |
7911 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7912 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7913 | path_put(&ns_path); |
e4222673 HB |
7914 | } |
7915 | } | |
7916 | ||
7917 | void perf_event_namespaces(struct task_struct *task) | |
7918 | { | |
7919 | struct perf_namespaces_event namespaces_event; | |
7920 | struct perf_ns_link_info *ns_link_info; | |
7921 | ||
7922 | if (!atomic_read(&nr_namespaces_events)) | |
7923 | return; | |
7924 | ||
7925 | namespaces_event = (struct perf_namespaces_event){ | |
7926 | .task = task, | |
7927 | .event_id = { | |
7928 | .header = { | |
7929 | .type = PERF_RECORD_NAMESPACES, | |
7930 | .misc = 0, | |
7931 | .size = sizeof(namespaces_event.event_id), | |
7932 | }, | |
7933 | /* .pid */ | |
7934 | /* .tid */ | |
7935 | .nr_namespaces = NR_NAMESPACES, | |
7936 | /* .link_info[NR_NAMESPACES] */ | |
7937 | }, | |
7938 | }; | |
7939 | ||
7940 | ns_link_info = namespaces_event.event_id.link_info; | |
7941 | ||
7942 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7943 | task, &mntns_operations); | |
7944 | ||
7945 | #ifdef CONFIG_USER_NS | |
7946 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7947 | task, &userns_operations); | |
7948 | #endif | |
7949 | #ifdef CONFIG_NET_NS | |
7950 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7951 | task, &netns_operations); | |
7952 | #endif | |
7953 | #ifdef CONFIG_UTS_NS | |
7954 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7955 | task, &utsns_operations); | |
7956 | #endif | |
7957 | #ifdef CONFIG_IPC_NS | |
7958 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7959 | task, &ipcns_operations); | |
7960 | #endif | |
7961 | #ifdef CONFIG_PID_NS | |
7962 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7963 | task, &pidns_operations); | |
7964 | #endif | |
7965 | #ifdef CONFIG_CGROUPS | |
7966 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7967 | task, &cgroupns_operations); | |
7968 | #endif | |
7969 | ||
7970 | perf_iterate_sb(perf_event_namespaces_output, | |
7971 | &namespaces_event, | |
7972 | NULL); | |
7973 | } | |
7974 | ||
96aaab68 NK |
7975 | /* |
7976 | * cgroup tracking | |
7977 | */ | |
7978 | #ifdef CONFIG_CGROUP_PERF | |
7979 | ||
7980 | struct perf_cgroup_event { | |
7981 | char *path; | |
7982 | int path_size; | |
7983 | struct { | |
7984 | struct perf_event_header header; | |
7985 | u64 id; | |
7986 | char path[]; | |
7987 | } event_id; | |
7988 | }; | |
7989 | ||
7990 | static int perf_event_cgroup_match(struct perf_event *event) | |
7991 | { | |
7992 | return event->attr.cgroup; | |
7993 | } | |
7994 | ||
7995 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
7996 | { | |
7997 | struct perf_cgroup_event *cgroup_event = data; | |
7998 | struct perf_output_handle handle; | |
7999 | struct perf_sample_data sample; | |
8000 | u16 header_size = cgroup_event->event_id.header.size; | |
8001 | int ret; | |
8002 | ||
8003 | if (!perf_event_cgroup_match(event)) | |
8004 | return; | |
8005 | ||
8006 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
8007 | &sample, event); | |
267fb273 | 8008 | ret = perf_output_begin(&handle, &sample, event, |
96aaab68 NK |
8009 | cgroup_event->event_id.header.size); |
8010 | if (ret) | |
8011 | goto out; | |
8012 | ||
8013 | perf_output_put(&handle, cgroup_event->event_id); | |
8014 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
8015 | ||
8016 | perf_event__output_id_sample(event, &handle, &sample); | |
8017 | ||
8018 | perf_output_end(&handle); | |
8019 | out: | |
8020 | cgroup_event->event_id.header.size = header_size; | |
8021 | } | |
8022 | ||
8023 | static void perf_event_cgroup(struct cgroup *cgrp) | |
8024 | { | |
8025 | struct perf_cgroup_event cgroup_event; | |
8026 | char path_enomem[16] = "//enomem"; | |
8027 | char *pathname; | |
8028 | size_t size; | |
8029 | ||
8030 | if (!atomic_read(&nr_cgroup_events)) | |
8031 | return; | |
8032 | ||
8033 | cgroup_event = (struct perf_cgroup_event){ | |
8034 | .event_id = { | |
8035 | .header = { | |
8036 | .type = PERF_RECORD_CGROUP, | |
8037 | .misc = 0, | |
8038 | .size = sizeof(cgroup_event.event_id), | |
8039 | }, | |
8040 | .id = cgroup_id(cgrp), | |
8041 | }, | |
8042 | }; | |
8043 | ||
8044 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
8045 | if (pathname == NULL) { | |
8046 | cgroup_event.path = path_enomem; | |
8047 | } else { | |
8048 | /* just to be sure to have enough space for alignment */ | |
8049 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
8050 | cgroup_event.path = pathname; | |
8051 | } | |
8052 | ||
8053 | /* | |
8054 | * Since our buffer works in 8 byte units we need to align our string | |
8055 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8056 | * zero'd out to avoid leaking random bits to userspace. | |
8057 | */ | |
8058 | size = strlen(cgroup_event.path) + 1; | |
8059 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8060 | cgroup_event.path[size++] = '\0'; | |
8061 | ||
8062 | cgroup_event.event_id.header.size += size; | |
8063 | cgroup_event.path_size = size; | |
8064 | ||
8065 | perf_iterate_sb(perf_event_cgroup_output, | |
8066 | &cgroup_event, | |
8067 | NULL); | |
8068 | ||
8069 | kfree(pathname); | |
8070 | } | |
8071 | ||
8072 | #endif | |
8073 | ||
0a4a9391 PZ |
8074 | /* |
8075 | * mmap tracking | |
8076 | */ | |
8077 | ||
8078 | struct perf_mmap_event { | |
089dd79d PZ |
8079 | struct vm_area_struct *vma; |
8080 | ||
8081 | const char *file_name; | |
8082 | int file_size; | |
13d7a241 SE |
8083 | int maj, min; |
8084 | u64 ino; | |
8085 | u64 ino_generation; | |
f972eb63 | 8086 | u32 prot, flags; |
0a4a9391 PZ |
8087 | |
8088 | struct { | |
8089 | struct perf_event_header header; | |
8090 | ||
8091 | u32 pid; | |
8092 | u32 tid; | |
8093 | u64 start; | |
8094 | u64 len; | |
8095 | u64 pgoff; | |
cdd6c482 | 8096 | } event_id; |
0a4a9391 PZ |
8097 | }; |
8098 | ||
67516844 JO |
8099 | static int perf_event_mmap_match(struct perf_event *event, |
8100 | void *data) | |
8101 | { | |
8102 | struct perf_mmap_event *mmap_event = data; | |
8103 | struct vm_area_struct *vma = mmap_event->vma; | |
8104 | int executable = vma->vm_flags & VM_EXEC; | |
8105 | ||
8106 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 8107 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
8108 | } |
8109 | ||
cdd6c482 | 8110 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 8111 | void *data) |
0a4a9391 | 8112 | { |
52d857a8 | 8113 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 8114 | struct perf_output_handle handle; |
c980d109 | 8115 | struct perf_sample_data sample; |
cdd6c482 | 8116 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 8117 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 8118 | int ret; |
0a4a9391 | 8119 | |
67516844 JO |
8120 | if (!perf_event_mmap_match(event, data)) |
8121 | return; | |
8122 | ||
13d7a241 SE |
8123 | if (event->attr.mmap2) { |
8124 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
8125 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
8126 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
8127 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 8128 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
8129 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
8130 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
8131 | } |
8132 | ||
c980d109 | 8133 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
267fb273 | 8134 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8135 | mmap_event->event_id.header.size); |
0a4a9391 | 8136 | if (ret) |
c980d109 | 8137 | goto out; |
0a4a9391 | 8138 | |
cdd6c482 IM |
8139 | mmap_event->event_id.pid = perf_event_pid(event, current); |
8140 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 8141 | |
cdd6c482 | 8142 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
8143 | |
8144 | if (event->attr.mmap2) { | |
8145 | perf_output_put(&handle, mmap_event->maj); | |
8146 | perf_output_put(&handle, mmap_event->min); | |
8147 | perf_output_put(&handle, mmap_event->ino); | |
8148 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
8149 | perf_output_put(&handle, mmap_event->prot); |
8150 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
8151 | } |
8152 | ||
76369139 | 8153 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 8154 | mmap_event->file_size); |
c980d109 ACM |
8155 | |
8156 | perf_event__output_id_sample(event, &handle, &sample); | |
8157 | ||
78d613eb | 8158 | perf_output_end(&handle); |
c980d109 ACM |
8159 | out: |
8160 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 8161 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
8162 | } |
8163 | ||
cdd6c482 | 8164 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 8165 | { |
089dd79d PZ |
8166 | struct vm_area_struct *vma = mmap_event->vma; |
8167 | struct file *file = vma->vm_file; | |
13d7a241 SE |
8168 | int maj = 0, min = 0; |
8169 | u64 ino = 0, gen = 0; | |
f972eb63 | 8170 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
8171 | unsigned int size; |
8172 | char tmp[16]; | |
8173 | char *buf = NULL; | |
2c42cfbf | 8174 | char *name; |
413ee3b4 | 8175 | |
0b3589be PZ |
8176 | if (vma->vm_flags & VM_READ) |
8177 | prot |= PROT_READ; | |
8178 | if (vma->vm_flags & VM_WRITE) | |
8179 | prot |= PROT_WRITE; | |
8180 | if (vma->vm_flags & VM_EXEC) | |
8181 | prot |= PROT_EXEC; | |
8182 | ||
8183 | if (vma->vm_flags & VM_MAYSHARE) | |
8184 | flags = MAP_SHARED; | |
8185 | else | |
8186 | flags = MAP_PRIVATE; | |
8187 | ||
8188 | if (vma->vm_flags & VM_DENYWRITE) | |
8189 | flags |= MAP_DENYWRITE; | |
8190 | if (vma->vm_flags & VM_MAYEXEC) | |
8191 | flags |= MAP_EXECUTABLE; | |
8192 | if (vma->vm_flags & VM_LOCKED) | |
8193 | flags |= MAP_LOCKED; | |
03911132 | 8194 | if (is_vm_hugetlb_page(vma)) |
0b3589be PZ |
8195 | flags |= MAP_HUGETLB; |
8196 | ||
0a4a9391 | 8197 | if (file) { |
13d7a241 SE |
8198 | struct inode *inode; |
8199 | dev_t dev; | |
3ea2f2b9 | 8200 | |
2c42cfbf | 8201 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 8202 | if (!buf) { |
c7e548b4 ON |
8203 | name = "//enomem"; |
8204 | goto cpy_name; | |
0a4a9391 | 8205 | } |
413ee3b4 | 8206 | /* |
3ea2f2b9 | 8207 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
8208 | * need to add enough zero bytes after the string to handle |
8209 | * the 64bit alignment we do later. | |
8210 | */ | |
9bf39ab2 | 8211 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 8212 | if (IS_ERR(name)) { |
c7e548b4 ON |
8213 | name = "//toolong"; |
8214 | goto cpy_name; | |
0a4a9391 | 8215 | } |
13d7a241 SE |
8216 | inode = file_inode(vma->vm_file); |
8217 | dev = inode->i_sb->s_dev; | |
8218 | ino = inode->i_ino; | |
8219 | gen = inode->i_generation; | |
8220 | maj = MAJOR(dev); | |
8221 | min = MINOR(dev); | |
f972eb63 | 8222 | |
c7e548b4 | 8223 | goto got_name; |
0a4a9391 | 8224 | } else { |
fbe26abe JO |
8225 | if (vma->vm_ops && vma->vm_ops->name) { |
8226 | name = (char *) vma->vm_ops->name(vma); | |
8227 | if (name) | |
8228 | goto cpy_name; | |
8229 | } | |
8230 | ||
2c42cfbf | 8231 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8232 | if (name) |
8233 | goto cpy_name; | |
089dd79d | 8234 | |
32c5fb7e | 8235 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8236 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8237 | name = "[heap]"; |
8238 | goto cpy_name; | |
32c5fb7e ON |
8239 | } |
8240 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8241 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8242 | name = "[stack]"; |
8243 | goto cpy_name; | |
089dd79d PZ |
8244 | } |
8245 | ||
c7e548b4 ON |
8246 | name = "//anon"; |
8247 | goto cpy_name; | |
0a4a9391 PZ |
8248 | } |
8249 | ||
c7e548b4 ON |
8250 | cpy_name: |
8251 | strlcpy(tmp, name, sizeof(tmp)); | |
8252 | name = tmp; | |
0a4a9391 | 8253 | got_name: |
2c42cfbf PZ |
8254 | /* |
8255 | * Since our buffer works in 8 byte units we need to align our string | |
8256 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8257 | * zero'd out to avoid leaking random bits to userspace. | |
8258 | */ | |
8259 | size = strlen(name)+1; | |
8260 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8261 | name[size++] = '\0'; | |
0a4a9391 PZ |
8262 | |
8263 | mmap_event->file_name = name; | |
8264 | mmap_event->file_size = size; | |
13d7a241 SE |
8265 | mmap_event->maj = maj; |
8266 | mmap_event->min = min; | |
8267 | mmap_event->ino = ino; | |
8268 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8269 | mmap_event->prot = prot; |
8270 | mmap_event->flags = flags; | |
0a4a9391 | 8271 | |
2fe85427 SE |
8272 | if (!(vma->vm_flags & VM_EXEC)) |
8273 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8274 | ||
cdd6c482 | 8275 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8276 | |
aab5b71e | 8277 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8278 | mmap_event, |
8279 | NULL); | |
665c2142 | 8280 | |
0a4a9391 PZ |
8281 | kfree(buf); |
8282 | } | |
8283 | ||
375637bc AS |
8284 | /* |
8285 | * Check whether inode and address range match filter criteria. | |
8286 | */ | |
8287 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8288 | struct file *file, unsigned long offset, | |
8289 | unsigned long size) | |
8290 | { | |
7f635ff1 MP |
8291 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8292 | if (!filter->path.dentry) | |
8293 | return false; | |
8294 | ||
9511bce9 | 8295 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8296 | return false; |
8297 | ||
8298 | if (filter->offset > offset + size) | |
8299 | return false; | |
8300 | ||
8301 | if (filter->offset + filter->size < offset) | |
8302 | return false; | |
8303 | ||
8304 | return true; | |
8305 | } | |
8306 | ||
c60f83b8 AS |
8307 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8308 | struct vm_area_struct *vma, | |
8309 | struct perf_addr_filter_range *fr) | |
8310 | { | |
8311 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8312 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8313 | struct file *file = vma->vm_file; | |
8314 | ||
8315 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8316 | return false; | |
8317 | ||
8318 | if (filter->offset < off) { | |
8319 | fr->start = vma->vm_start; | |
8320 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8321 | } else { | |
8322 | fr->start = vma->vm_start + filter->offset - off; | |
8323 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8324 | } | |
8325 | ||
8326 | return true; | |
8327 | } | |
8328 | ||
375637bc AS |
8329 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8330 | { | |
8331 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8332 | struct vm_area_struct *vma = data; | |
375637bc AS |
8333 | struct perf_addr_filter *filter; |
8334 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8335 | unsigned long flags; |
375637bc AS |
8336 | |
8337 | if (!has_addr_filter(event)) | |
8338 | return; | |
8339 | ||
c60f83b8 | 8340 | if (!vma->vm_file) |
375637bc AS |
8341 | return; |
8342 | ||
8343 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8344 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8345 | if (perf_addr_filter_vma_adjust(filter, vma, |
8346 | &event->addr_filter_ranges[count])) | |
375637bc | 8347 | restart++; |
375637bc AS |
8348 | |
8349 | count++; | |
8350 | } | |
8351 | ||
8352 | if (restart) | |
8353 | event->addr_filters_gen++; | |
8354 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8355 | ||
8356 | if (restart) | |
767ae086 | 8357 | perf_event_stop(event, 1); |
375637bc AS |
8358 | } |
8359 | ||
8360 | /* | |
8361 | * Adjust all task's events' filters to the new vma | |
8362 | */ | |
8363 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8364 | { | |
8365 | struct perf_event_context *ctx; | |
8366 | int ctxn; | |
8367 | ||
12b40a23 MP |
8368 | /* |
8369 | * Data tracing isn't supported yet and as such there is no need | |
8370 | * to keep track of anything that isn't related to executable code: | |
8371 | */ | |
8372 | if (!(vma->vm_flags & VM_EXEC)) | |
8373 | return; | |
8374 | ||
375637bc AS |
8375 | rcu_read_lock(); |
8376 | for_each_task_context_nr(ctxn) { | |
8377 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8378 | if (!ctx) | |
8379 | continue; | |
8380 | ||
aab5b71e | 8381 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8382 | } |
8383 | rcu_read_unlock(); | |
8384 | } | |
8385 | ||
3af9e859 | 8386 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8387 | { |
9ee318a7 PZ |
8388 | struct perf_mmap_event mmap_event; |
8389 | ||
cdd6c482 | 8390 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8391 | return; |
8392 | ||
8393 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8394 | .vma = vma, |
573402db PZ |
8395 | /* .file_name */ |
8396 | /* .file_size */ | |
cdd6c482 | 8397 | .event_id = { |
573402db | 8398 | .header = { |
cdd6c482 | 8399 | .type = PERF_RECORD_MMAP, |
39447b38 | 8400 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8401 | /* .size */ |
8402 | }, | |
8403 | /* .pid */ | |
8404 | /* .tid */ | |
089dd79d PZ |
8405 | .start = vma->vm_start, |
8406 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8407 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8408 | }, |
13d7a241 SE |
8409 | /* .maj (attr_mmap2 only) */ |
8410 | /* .min (attr_mmap2 only) */ | |
8411 | /* .ino (attr_mmap2 only) */ | |
8412 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8413 | /* .prot (attr_mmap2 only) */ |
8414 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8415 | }; |
8416 | ||
375637bc | 8417 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8418 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8419 | } |
8420 | ||
68db7e98 AS |
8421 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8422 | unsigned long size, u64 flags) | |
8423 | { | |
8424 | struct perf_output_handle handle; | |
8425 | struct perf_sample_data sample; | |
8426 | struct perf_aux_event { | |
8427 | struct perf_event_header header; | |
8428 | u64 offset; | |
8429 | u64 size; | |
8430 | u64 flags; | |
8431 | } rec = { | |
8432 | .header = { | |
8433 | .type = PERF_RECORD_AUX, | |
8434 | .misc = 0, | |
8435 | .size = sizeof(rec), | |
8436 | }, | |
8437 | .offset = head, | |
8438 | .size = size, | |
8439 | .flags = flags, | |
8440 | }; | |
8441 | int ret; | |
8442 | ||
8443 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8444 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
68db7e98 AS |
8445 | |
8446 | if (ret) | |
8447 | return; | |
8448 | ||
8449 | perf_output_put(&handle, rec); | |
8450 | perf_event__output_id_sample(event, &handle, &sample); | |
8451 | ||
8452 | perf_output_end(&handle); | |
8453 | } | |
8454 | ||
f38b0dbb KL |
8455 | /* |
8456 | * Lost/dropped samples logging | |
8457 | */ | |
8458 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8459 | { | |
8460 | struct perf_output_handle handle; | |
8461 | struct perf_sample_data sample; | |
8462 | int ret; | |
8463 | ||
8464 | struct { | |
8465 | struct perf_event_header header; | |
8466 | u64 lost; | |
8467 | } lost_samples_event = { | |
8468 | .header = { | |
8469 | .type = PERF_RECORD_LOST_SAMPLES, | |
8470 | .misc = 0, | |
8471 | .size = sizeof(lost_samples_event), | |
8472 | }, | |
8473 | .lost = lost, | |
8474 | }; | |
8475 | ||
8476 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8477 | ||
267fb273 | 8478 | ret = perf_output_begin(&handle, &sample, event, |
f38b0dbb KL |
8479 | lost_samples_event.header.size); |
8480 | if (ret) | |
8481 | return; | |
8482 | ||
8483 | perf_output_put(&handle, lost_samples_event); | |
8484 | perf_event__output_id_sample(event, &handle, &sample); | |
8485 | perf_output_end(&handle); | |
8486 | } | |
8487 | ||
45ac1403 AH |
8488 | /* |
8489 | * context_switch tracking | |
8490 | */ | |
8491 | ||
8492 | struct perf_switch_event { | |
8493 | struct task_struct *task; | |
8494 | struct task_struct *next_prev; | |
8495 | ||
8496 | struct { | |
8497 | struct perf_event_header header; | |
8498 | u32 next_prev_pid; | |
8499 | u32 next_prev_tid; | |
8500 | } event_id; | |
8501 | }; | |
8502 | ||
8503 | static int perf_event_switch_match(struct perf_event *event) | |
8504 | { | |
8505 | return event->attr.context_switch; | |
8506 | } | |
8507 | ||
8508 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8509 | { | |
8510 | struct perf_switch_event *se = data; | |
8511 | struct perf_output_handle handle; | |
8512 | struct perf_sample_data sample; | |
8513 | int ret; | |
8514 | ||
8515 | if (!perf_event_switch_match(event)) | |
8516 | return; | |
8517 | ||
8518 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8519 | if (event->ctx->task) { | |
8520 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8521 | se->event_id.header.size = sizeof(se->event_id.header); | |
8522 | } else { | |
8523 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8524 | se->event_id.header.size = sizeof(se->event_id); | |
8525 | se->event_id.next_prev_pid = | |
8526 | perf_event_pid(event, se->next_prev); | |
8527 | se->event_id.next_prev_tid = | |
8528 | perf_event_tid(event, se->next_prev); | |
8529 | } | |
8530 | ||
8531 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8532 | ||
267fb273 | 8533 | ret = perf_output_begin(&handle, &sample, event, se->event_id.header.size); |
45ac1403 AH |
8534 | if (ret) |
8535 | return; | |
8536 | ||
8537 | if (event->ctx->task) | |
8538 | perf_output_put(&handle, se->event_id.header); | |
8539 | else | |
8540 | perf_output_put(&handle, se->event_id); | |
8541 | ||
8542 | perf_event__output_id_sample(event, &handle, &sample); | |
8543 | ||
8544 | perf_output_end(&handle); | |
8545 | } | |
8546 | ||
8547 | static void perf_event_switch(struct task_struct *task, | |
8548 | struct task_struct *next_prev, bool sched_in) | |
8549 | { | |
8550 | struct perf_switch_event switch_event; | |
8551 | ||
8552 | /* N.B. caller checks nr_switch_events != 0 */ | |
8553 | ||
8554 | switch_event = (struct perf_switch_event){ | |
8555 | .task = task, | |
8556 | .next_prev = next_prev, | |
8557 | .event_id = { | |
8558 | .header = { | |
8559 | /* .type */ | |
8560 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8561 | /* .size */ | |
8562 | }, | |
8563 | /* .next_prev_pid */ | |
8564 | /* .next_prev_tid */ | |
8565 | }, | |
8566 | }; | |
8567 | ||
101592b4 AB |
8568 | if (!sched_in && task->state == TASK_RUNNING) |
8569 | switch_event.event_id.header.misc |= | |
8570 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8571 | ||
aab5b71e | 8572 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8573 | &switch_event, |
8574 | NULL); | |
8575 | } | |
8576 | ||
a78ac325 PZ |
8577 | /* |
8578 | * IRQ throttle logging | |
8579 | */ | |
8580 | ||
cdd6c482 | 8581 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8582 | { |
8583 | struct perf_output_handle handle; | |
c980d109 | 8584 | struct perf_sample_data sample; |
a78ac325 PZ |
8585 | int ret; |
8586 | ||
8587 | struct { | |
8588 | struct perf_event_header header; | |
8589 | u64 time; | |
cca3f454 | 8590 | u64 id; |
7f453c24 | 8591 | u64 stream_id; |
a78ac325 PZ |
8592 | } throttle_event = { |
8593 | .header = { | |
cdd6c482 | 8594 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8595 | .misc = 0, |
8596 | .size = sizeof(throttle_event), | |
8597 | }, | |
34f43927 | 8598 | .time = perf_event_clock(event), |
cdd6c482 IM |
8599 | .id = primary_event_id(event), |
8600 | .stream_id = event->id, | |
a78ac325 PZ |
8601 | }; |
8602 | ||
966ee4d6 | 8603 | if (enable) |
cdd6c482 | 8604 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8605 | |
c980d109 ACM |
8606 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8607 | ||
267fb273 | 8608 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8609 | throttle_event.header.size); |
a78ac325 PZ |
8610 | if (ret) |
8611 | return; | |
8612 | ||
8613 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8614 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8615 | perf_output_end(&handle); |
8616 | } | |
8617 | ||
76193a94 SL |
8618 | /* |
8619 | * ksymbol register/unregister tracking | |
8620 | */ | |
8621 | ||
8622 | struct perf_ksymbol_event { | |
8623 | const char *name; | |
8624 | int name_len; | |
8625 | struct { | |
8626 | struct perf_event_header header; | |
8627 | u64 addr; | |
8628 | u32 len; | |
8629 | u16 ksym_type; | |
8630 | u16 flags; | |
8631 | } event_id; | |
8632 | }; | |
8633 | ||
8634 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8635 | { | |
8636 | return event->attr.ksymbol; | |
8637 | } | |
8638 | ||
8639 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8640 | { | |
8641 | struct perf_ksymbol_event *ksymbol_event = data; | |
8642 | struct perf_output_handle handle; | |
8643 | struct perf_sample_data sample; | |
8644 | int ret; | |
8645 | ||
8646 | if (!perf_event_ksymbol_match(event)) | |
8647 | return; | |
8648 | ||
8649 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8650 | &sample, event); | |
267fb273 | 8651 | ret = perf_output_begin(&handle, &sample, event, |
76193a94 SL |
8652 | ksymbol_event->event_id.header.size); |
8653 | if (ret) | |
8654 | return; | |
8655 | ||
8656 | perf_output_put(&handle, ksymbol_event->event_id); | |
8657 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8658 | perf_event__output_id_sample(event, &handle, &sample); | |
8659 | ||
8660 | perf_output_end(&handle); | |
8661 | } | |
8662 | ||
8663 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8664 | const char *sym) | |
8665 | { | |
8666 | struct perf_ksymbol_event ksymbol_event; | |
8667 | char name[KSYM_NAME_LEN]; | |
8668 | u16 flags = 0; | |
8669 | int name_len; | |
8670 | ||
8671 | if (!atomic_read(&nr_ksymbol_events)) | |
8672 | return; | |
8673 | ||
8674 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8675 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8676 | goto err; | |
8677 | ||
8678 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8679 | name_len = strlen(name) + 1; | |
8680 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8681 | name[name_len++] = '\0'; | |
8682 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8683 | ||
8684 | if (unregister) | |
8685 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8686 | ||
8687 | ksymbol_event = (struct perf_ksymbol_event){ | |
8688 | .name = name, | |
8689 | .name_len = name_len, | |
8690 | .event_id = { | |
8691 | .header = { | |
8692 | .type = PERF_RECORD_KSYMBOL, | |
8693 | .size = sizeof(ksymbol_event.event_id) + | |
8694 | name_len, | |
8695 | }, | |
8696 | .addr = addr, | |
8697 | .len = len, | |
8698 | .ksym_type = ksym_type, | |
8699 | .flags = flags, | |
8700 | }, | |
8701 | }; | |
8702 | ||
8703 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8704 | return; | |
8705 | err: | |
8706 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8707 | } | |
8708 | ||
6ee52e2a SL |
8709 | /* |
8710 | * bpf program load/unload tracking | |
8711 | */ | |
8712 | ||
8713 | struct perf_bpf_event { | |
8714 | struct bpf_prog *prog; | |
8715 | struct { | |
8716 | struct perf_event_header header; | |
8717 | u16 type; | |
8718 | u16 flags; | |
8719 | u32 id; | |
8720 | u8 tag[BPF_TAG_SIZE]; | |
8721 | } event_id; | |
8722 | }; | |
8723 | ||
8724 | static int perf_event_bpf_match(struct perf_event *event) | |
8725 | { | |
8726 | return event->attr.bpf_event; | |
8727 | } | |
8728 | ||
8729 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8730 | { | |
8731 | struct perf_bpf_event *bpf_event = data; | |
8732 | struct perf_output_handle handle; | |
8733 | struct perf_sample_data sample; | |
8734 | int ret; | |
8735 | ||
8736 | if (!perf_event_bpf_match(event)) | |
8737 | return; | |
8738 | ||
8739 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8740 | &sample, event); | |
267fb273 | 8741 | ret = perf_output_begin(&handle, data, event, |
6ee52e2a SL |
8742 | bpf_event->event_id.header.size); |
8743 | if (ret) | |
8744 | return; | |
8745 | ||
8746 | perf_output_put(&handle, bpf_event->event_id); | |
8747 | perf_event__output_id_sample(event, &handle, &sample); | |
8748 | ||
8749 | perf_output_end(&handle); | |
8750 | } | |
8751 | ||
8752 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8753 | enum perf_bpf_event_type type) | |
8754 | { | |
8755 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8756 | int i; |
8757 | ||
8758 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8759 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8760 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8761 | prog->jited_len, unregister, |
8762 | prog->aux->ksym.name); | |
6ee52e2a SL |
8763 | } else { |
8764 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8765 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8766 | ||
6ee52e2a SL |
8767 | perf_event_ksymbol( |
8768 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8769 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8770 | subprog->jited_len, unregister, |
8771 | prog->aux->ksym.name); | |
6ee52e2a SL |
8772 | } |
8773 | } | |
8774 | } | |
8775 | ||
8776 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8777 | enum perf_bpf_event_type type, | |
8778 | u16 flags) | |
8779 | { | |
8780 | struct perf_bpf_event bpf_event; | |
8781 | ||
8782 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8783 | type >= PERF_BPF_EVENT_MAX) | |
8784 | return; | |
8785 | ||
8786 | switch (type) { | |
8787 | case PERF_BPF_EVENT_PROG_LOAD: | |
8788 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8789 | if (atomic_read(&nr_ksymbol_events)) | |
8790 | perf_event_bpf_emit_ksymbols(prog, type); | |
8791 | break; | |
8792 | default: | |
8793 | break; | |
8794 | } | |
8795 | ||
8796 | if (!atomic_read(&nr_bpf_events)) | |
8797 | return; | |
8798 | ||
8799 | bpf_event = (struct perf_bpf_event){ | |
8800 | .prog = prog, | |
8801 | .event_id = { | |
8802 | .header = { | |
8803 | .type = PERF_RECORD_BPF_EVENT, | |
8804 | .size = sizeof(bpf_event.event_id), | |
8805 | }, | |
8806 | .type = type, | |
8807 | .flags = flags, | |
8808 | .id = prog->aux->id, | |
8809 | }, | |
8810 | }; | |
8811 | ||
8812 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8813 | ||
8814 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8815 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8816 | } | |
8817 | ||
e17d43b9 AH |
8818 | struct perf_text_poke_event { |
8819 | const void *old_bytes; | |
8820 | const void *new_bytes; | |
8821 | size_t pad; | |
8822 | u16 old_len; | |
8823 | u16 new_len; | |
8824 | ||
8825 | struct { | |
8826 | struct perf_event_header header; | |
8827 | ||
8828 | u64 addr; | |
8829 | } event_id; | |
8830 | }; | |
8831 | ||
8832 | static int perf_event_text_poke_match(struct perf_event *event) | |
8833 | { | |
8834 | return event->attr.text_poke; | |
8835 | } | |
8836 | ||
8837 | static void perf_event_text_poke_output(struct perf_event *event, void *data) | |
8838 | { | |
8839 | struct perf_text_poke_event *text_poke_event = data; | |
8840 | struct perf_output_handle handle; | |
8841 | struct perf_sample_data sample; | |
8842 | u64 padding = 0; | |
8843 | int ret; | |
8844 | ||
8845 | if (!perf_event_text_poke_match(event)) | |
8846 | return; | |
8847 | ||
8848 | perf_event_header__init_id(&text_poke_event->event_id.header, &sample, event); | |
8849 | ||
267fb273 PZ |
8850 | ret = perf_output_begin(&handle, &sample, event, |
8851 | text_poke_event->event_id.header.size); | |
e17d43b9 AH |
8852 | if (ret) |
8853 | return; | |
8854 | ||
8855 | perf_output_put(&handle, text_poke_event->event_id); | |
8856 | perf_output_put(&handle, text_poke_event->old_len); | |
8857 | perf_output_put(&handle, text_poke_event->new_len); | |
8858 | ||
8859 | __output_copy(&handle, text_poke_event->old_bytes, text_poke_event->old_len); | |
8860 | __output_copy(&handle, text_poke_event->new_bytes, text_poke_event->new_len); | |
8861 | ||
8862 | if (text_poke_event->pad) | |
8863 | __output_copy(&handle, &padding, text_poke_event->pad); | |
8864 | ||
8865 | perf_event__output_id_sample(event, &handle, &sample); | |
8866 | ||
8867 | perf_output_end(&handle); | |
8868 | } | |
8869 | ||
8870 | void perf_event_text_poke(const void *addr, const void *old_bytes, | |
8871 | size_t old_len, const void *new_bytes, size_t new_len) | |
8872 | { | |
8873 | struct perf_text_poke_event text_poke_event; | |
8874 | size_t tot, pad; | |
8875 | ||
8876 | if (!atomic_read(&nr_text_poke_events)) | |
8877 | return; | |
8878 | ||
8879 | tot = sizeof(text_poke_event.old_len) + old_len; | |
8880 | tot += sizeof(text_poke_event.new_len) + new_len; | |
8881 | pad = ALIGN(tot, sizeof(u64)) - tot; | |
8882 | ||
8883 | text_poke_event = (struct perf_text_poke_event){ | |
8884 | .old_bytes = old_bytes, | |
8885 | .new_bytes = new_bytes, | |
8886 | .pad = pad, | |
8887 | .old_len = old_len, | |
8888 | .new_len = new_len, | |
8889 | .event_id = { | |
8890 | .header = { | |
8891 | .type = PERF_RECORD_TEXT_POKE, | |
8892 | .misc = PERF_RECORD_MISC_KERNEL, | |
8893 | .size = sizeof(text_poke_event.event_id) + tot + pad, | |
8894 | }, | |
8895 | .addr = (unsigned long)addr, | |
8896 | }, | |
8897 | }; | |
8898 | ||
8899 | perf_iterate_sb(perf_event_text_poke_output, &text_poke_event, NULL); | |
8900 | } | |
8901 | ||
8d4e6c4c AS |
8902 | void perf_event_itrace_started(struct perf_event *event) |
8903 | { | |
8904 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8905 | } | |
8906 | ||
ec0d7729 AS |
8907 | static void perf_log_itrace_start(struct perf_event *event) |
8908 | { | |
8909 | struct perf_output_handle handle; | |
8910 | struct perf_sample_data sample; | |
8911 | struct perf_aux_event { | |
8912 | struct perf_event_header header; | |
8913 | u32 pid; | |
8914 | u32 tid; | |
8915 | } rec; | |
8916 | int ret; | |
8917 | ||
8918 | if (event->parent) | |
8919 | event = event->parent; | |
8920 | ||
8921 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8922 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8923 | return; |
8924 | ||
ec0d7729 AS |
8925 | rec.header.type = PERF_RECORD_ITRACE_START; |
8926 | rec.header.misc = 0; | |
8927 | rec.header.size = sizeof(rec); | |
8928 | rec.pid = perf_event_pid(event, current); | |
8929 | rec.tid = perf_event_tid(event, current); | |
8930 | ||
8931 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8932 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
ec0d7729 AS |
8933 | |
8934 | if (ret) | |
8935 | return; | |
8936 | ||
8937 | perf_output_put(&handle, rec); | |
8938 | perf_event__output_id_sample(event, &handle, &sample); | |
8939 | ||
8940 | perf_output_end(&handle); | |
8941 | } | |
8942 | ||
475113d9 JO |
8943 | static int |
8944 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8945 | { |
cdd6c482 | 8946 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8947 | int ret = 0; |
475113d9 | 8948 | u64 seq; |
96398826 | 8949 | |
e050e3f0 SE |
8950 | seq = __this_cpu_read(perf_throttled_seq); |
8951 | if (seq != hwc->interrupts_seq) { | |
8952 | hwc->interrupts_seq = seq; | |
8953 | hwc->interrupts = 1; | |
8954 | } else { | |
8955 | hwc->interrupts++; | |
8956 | if (unlikely(throttle | |
8957 | && hwc->interrupts >= max_samples_per_tick)) { | |
8958 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8959 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8960 | hwc->interrupts = MAX_INTERRUPTS; |
8961 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8962 | ret = 1; |
8963 | } | |
e050e3f0 | 8964 | } |
60db5e09 | 8965 | |
cdd6c482 | 8966 | if (event->attr.freq) { |
def0a9b2 | 8967 | u64 now = perf_clock(); |
abd50713 | 8968 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8969 | |
abd50713 | 8970 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8971 | |
abd50713 | 8972 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8973 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8974 | } |
8975 | ||
475113d9 JO |
8976 | return ret; |
8977 | } | |
8978 | ||
8979 | int perf_event_account_interrupt(struct perf_event *event) | |
8980 | { | |
8981 | return __perf_event_account_interrupt(event, 1); | |
8982 | } | |
8983 | ||
8984 | /* | |
8985 | * Generic event overflow handling, sampling. | |
8986 | */ | |
8987 | ||
8988 | static int __perf_event_overflow(struct perf_event *event, | |
8989 | int throttle, struct perf_sample_data *data, | |
8990 | struct pt_regs *regs) | |
8991 | { | |
8992 | int events = atomic_read(&event->event_limit); | |
8993 | int ret = 0; | |
8994 | ||
8995 | /* | |
8996 | * Non-sampling counters might still use the PMI to fold short | |
8997 | * hardware counters, ignore those. | |
8998 | */ | |
8999 | if (unlikely(!is_sampling_event(event))) | |
9000 | return 0; | |
9001 | ||
9002 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 9003 | |
2023b359 PZ |
9004 | /* |
9005 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 9006 | * events |
2023b359 PZ |
9007 | */ |
9008 | ||
cdd6c482 IM |
9009 | event->pending_kill = POLL_IN; |
9010 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 9011 | ret = 1; |
cdd6c482 | 9012 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
9013 | |
9014 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
9015 | } |
9016 | ||
aa6a5f3c | 9017 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 9018 | |
fed66e2c | 9019 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
9020 | event->pending_wakeup = 1; |
9021 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
9022 | } |
9023 | ||
79f14641 | 9024 | return ret; |
f6c7d5fe PZ |
9025 | } |
9026 | ||
a8b0ca17 | 9027 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
9028 | struct perf_sample_data *data, |
9029 | struct pt_regs *regs) | |
850bc73f | 9030 | { |
a8b0ca17 | 9031 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
9032 | } |
9033 | ||
15dbf27c | 9034 | /* |
cdd6c482 | 9035 | * Generic software event infrastructure |
15dbf27c PZ |
9036 | */ |
9037 | ||
b28ab83c PZ |
9038 | struct swevent_htable { |
9039 | struct swevent_hlist *swevent_hlist; | |
9040 | struct mutex hlist_mutex; | |
9041 | int hlist_refcount; | |
9042 | ||
9043 | /* Recursion avoidance in each contexts */ | |
9044 | int recursion[PERF_NR_CONTEXTS]; | |
9045 | }; | |
9046 | ||
9047 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
9048 | ||
7b4b6658 | 9049 | /* |
cdd6c482 IM |
9050 | * We directly increment event->count and keep a second value in |
9051 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
9052 | * is kept in the range [-sample_period, 0] so that we can use the |
9053 | * sign as trigger. | |
9054 | */ | |
9055 | ||
ab573844 | 9056 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 9057 | { |
cdd6c482 | 9058 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
9059 | u64 period = hwc->last_period; |
9060 | u64 nr, offset; | |
9061 | s64 old, val; | |
9062 | ||
9063 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
9064 | |
9065 | again: | |
e7850595 | 9066 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
9067 | if (val < 0) |
9068 | return 0; | |
15dbf27c | 9069 | |
7b4b6658 PZ |
9070 | nr = div64_u64(period + val, period); |
9071 | offset = nr * period; | |
9072 | val -= offset; | |
e7850595 | 9073 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 9074 | goto again; |
15dbf27c | 9075 | |
7b4b6658 | 9076 | return nr; |
15dbf27c PZ |
9077 | } |
9078 | ||
0cff784a | 9079 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 9080 | struct perf_sample_data *data, |
5622f295 | 9081 | struct pt_regs *regs) |
15dbf27c | 9082 | { |
cdd6c482 | 9083 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 9084 | int throttle = 0; |
15dbf27c | 9085 | |
0cff784a PZ |
9086 | if (!overflow) |
9087 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 9088 | |
7b4b6658 PZ |
9089 | if (hwc->interrupts == MAX_INTERRUPTS) |
9090 | return; | |
15dbf27c | 9091 | |
7b4b6658 | 9092 | for (; overflow; overflow--) { |
a8b0ca17 | 9093 | if (__perf_event_overflow(event, throttle, |
5622f295 | 9094 | data, regs)) { |
7b4b6658 PZ |
9095 | /* |
9096 | * We inhibit the overflow from happening when | |
9097 | * hwc->interrupts == MAX_INTERRUPTS. | |
9098 | */ | |
9099 | break; | |
9100 | } | |
cf450a73 | 9101 | throttle = 1; |
7b4b6658 | 9102 | } |
15dbf27c PZ |
9103 | } |
9104 | ||
a4eaf7f1 | 9105 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 9106 | struct perf_sample_data *data, |
5622f295 | 9107 | struct pt_regs *regs) |
7b4b6658 | 9108 | { |
cdd6c482 | 9109 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 9110 | |
e7850595 | 9111 | local64_add(nr, &event->count); |
d6d020e9 | 9112 | |
0cff784a PZ |
9113 | if (!regs) |
9114 | return; | |
9115 | ||
6c7e550f | 9116 | if (!is_sampling_event(event)) |
7b4b6658 | 9117 | return; |
d6d020e9 | 9118 | |
5d81e5cf AV |
9119 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
9120 | data->period = nr; | |
9121 | return perf_swevent_overflow(event, 1, data, regs); | |
9122 | } else | |
9123 | data->period = event->hw.last_period; | |
9124 | ||
0cff784a | 9125 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 9126 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 9127 | |
e7850595 | 9128 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 9129 | return; |
df1a132b | 9130 | |
a8b0ca17 | 9131 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
9132 | } |
9133 | ||
f5ffe02e FW |
9134 | static int perf_exclude_event(struct perf_event *event, |
9135 | struct pt_regs *regs) | |
9136 | { | |
a4eaf7f1 | 9137 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 9138 | return 1; |
a4eaf7f1 | 9139 | |
f5ffe02e FW |
9140 | if (regs) { |
9141 | if (event->attr.exclude_user && user_mode(regs)) | |
9142 | return 1; | |
9143 | ||
9144 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
9145 | return 1; | |
9146 | } | |
9147 | ||
9148 | return 0; | |
9149 | } | |
9150 | ||
cdd6c482 | 9151 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 9152 | enum perf_type_id type, |
6fb2915d LZ |
9153 | u32 event_id, |
9154 | struct perf_sample_data *data, | |
9155 | struct pt_regs *regs) | |
15dbf27c | 9156 | { |
cdd6c482 | 9157 | if (event->attr.type != type) |
a21ca2ca | 9158 | return 0; |
f5ffe02e | 9159 | |
cdd6c482 | 9160 | if (event->attr.config != event_id) |
15dbf27c PZ |
9161 | return 0; |
9162 | ||
f5ffe02e FW |
9163 | if (perf_exclude_event(event, regs)) |
9164 | return 0; | |
15dbf27c PZ |
9165 | |
9166 | return 1; | |
9167 | } | |
9168 | ||
76e1d904 FW |
9169 | static inline u64 swevent_hash(u64 type, u32 event_id) |
9170 | { | |
9171 | u64 val = event_id | (type << 32); | |
9172 | ||
9173 | return hash_64(val, SWEVENT_HLIST_BITS); | |
9174 | } | |
9175 | ||
49f135ed FW |
9176 | static inline struct hlist_head * |
9177 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 9178 | { |
49f135ed FW |
9179 | u64 hash = swevent_hash(type, event_id); |
9180 | ||
9181 | return &hlist->heads[hash]; | |
9182 | } | |
76e1d904 | 9183 | |
49f135ed FW |
9184 | /* For the read side: events when they trigger */ |
9185 | static inline struct hlist_head * | |
b28ab83c | 9186 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
9187 | { |
9188 | struct swevent_hlist *hlist; | |
76e1d904 | 9189 | |
b28ab83c | 9190 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
9191 | if (!hlist) |
9192 | return NULL; | |
9193 | ||
49f135ed FW |
9194 | return __find_swevent_head(hlist, type, event_id); |
9195 | } | |
9196 | ||
9197 | /* For the event head insertion and removal in the hlist */ | |
9198 | static inline struct hlist_head * | |
b28ab83c | 9199 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
9200 | { |
9201 | struct swevent_hlist *hlist; | |
9202 | u32 event_id = event->attr.config; | |
9203 | u64 type = event->attr.type; | |
9204 | ||
9205 | /* | |
9206 | * Event scheduling is always serialized against hlist allocation | |
9207 | * and release. Which makes the protected version suitable here. | |
9208 | * The context lock guarantees that. | |
9209 | */ | |
b28ab83c | 9210 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
9211 | lockdep_is_held(&event->ctx->lock)); |
9212 | if (!hlist) | |
9213 | return NULL; | |
9214 | ||
9215 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
9216 | } |
9217 | ||
9218 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 9219 | u64 nr, |
76e1d904 FW |
9220 | struct perf_sample_data *data, |
9221 | struct pt_regs *regs) | |
15dbf27c | 9222 | { |
4a32fea9 | 9223 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9224 | struct perf_event *event; |
76e1d904 | 9225 | struct hlist_head *head; |
15dbf27c | 9226 | |
76e1d904 | 9227 | rcu_read_lock(); |
b28ab83c | 9228 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
9229 | if (!head) |
9230 | goto end; | |
9231 | ||
b67bfe0d | 9232 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 9233 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 9234 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 9235 | } |
76e1d904 FW |
9236 | end: |
9237 | rcu_read_unlock(); | |
15dbf27c PZ |
9238 | } |
9239 | ||
86038c5e PZI |
9240 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
9241 | ||
4ed7c92d | 9242 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 9243 | { |
4a32fea9 | 9244 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 9245 | |
b28ab83c | 9246 | return get_recursion_context(swhash->recursion); |
96f6d444 | 9247 | } |
645e8cc0 | 9248 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 9249 | |
98b5c2c6 | 9250 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 9251 | { |
4a32fea9 | 9252 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 9253 | |
b28ab83c | 9254 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 9255 | } |
15dbf27c | 9256 | |
86038c5e | 9257 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 9258 | { |
a4234bfc | 9259 | struct perf_sample_data data; |
4ed7c92d | 9260 | |
86038c5e | 9261 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 9262 | return; |
a4234bfc | 9263 | |
fd0d000b | 9264 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 9265 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
9266 | } |
9267 | ||
9268 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
9269 | { | |
9270 | int rctx; | |
9271 | ||
9272 | preempt_disable_notrace(); | |
9273 | rctx = perf_swevent_get_recursion_context(); | |
9274 | if (unlikely(rctx < 0)) | |
9275 | goto fail; | |
9276 | ||
9277 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
9278 | |
9279 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 9280 | fail: |
1c024eca | 9281 | preempt_enable_notrace(); |
b8e83514 PZ |
9282 | } |
9283 | ||
cdd6c482 | 9284 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 9285 | { |
15dbf27c PZ |
9286 | } |
9287 | ||
a4eaf7f1 | 9288 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 9289 | { |
4a32fea9 | 9290 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9291 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
9292 | struct hlist_head *head; |
9293 | ||
6c7e550f | 9294 | if (is_sampling_event(event)) { |
7b4b6658 | 9295 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 9296 | perf_swevent_set_period(event); |
7b4b6658 | 9297 | } |
76e1d904 | 9298 | |
a4eaf7f1 PZ |
9299 | hwc->state = !(flags & PERF_EF_START); |
9300 | ||
b28ab83c | 9301 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9302 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9303 | return -EINVAL; |
9304 | ||
9305 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9306 | perf_event_update_userpage(event); |
76e1d904 | 9307 | |
15dbf27c PZ |
9308 | return 0; |
9309 | } | |
9310 | ||
a4eaf7f1 | 9311 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9312 | { |
76e1d904 | 9313 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9314 | } |
9315 | ||
a4eaf7f1 | 9316 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9317 | { |
a4eaf7f1 | 9318 | event->hw.state = 0; |
d6d020e9 | 9319 | } |
aa9c4c0f | 9320 | |
a4eaf7f1 | 9321 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9322 | { |
a4eaf7f1 | 9323 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9324 | } |
9325 | ||
49f135ed FW |
9326 | /* Deref the hlist from the update side */ |
9327 | static inline struct swevent_hlist * | |
b28ab83c | 9328 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9329 | { |
b28ab83c PZ |
9330 | return rcu_dereference_protected(swhash->swevent_hlist, |
9331 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9332 | } |
9333 | ||
b28ab83c | 9334 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9335 | { |
b28ab83c | 9336 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9337 | |
49f135ed | 9338 | if (!hlist) |
76e1d904 FW |
9339 | return; |
9340 | ||
70691d4a | 9341 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9342 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9343 | } |
9344 | ||
3b364d7b | 9345 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9346 | { |
b28ab83c | 9347 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9348 | |
b28ab83c | 9349 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9350 | |
b28ab83c PZ |
9351 | if (!--swhash->hlist_refcount) |
9352 | swevent_hlist_release(swhash); | |
76e1d904 | 9353 | |
b28ab83c | 9354 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9355 | } |
9356 | ||
3b364d7b | 9357 | static void swevent_hlist_put(void) |
76e1d904 FW |
9358 | { |
9359 | int cpu; | |
9360 | ||
76e1d904 | 9361 | for_each_possible_cpu(cpu) |
3b364d7b | 9362 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9363 | } |
9364 | ||
3b364d7b | 9365 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9366 | { |
b28ab83c | 9367 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9368 | int err = 0; |
9369 | ||
b28ab83c | 9370 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9371 | if (!swevent_hlist_deref(swhash) && |
9372 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9373 | struct swevent_hlist *hlist; |
9374 | ||
9375 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9376 | if (!hlist) { | |
9377 | err = -ENOMEM; | |
9378 | goto exit; | |
9379 | } | |
b28ab83c | 9380 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9381 | } |
b28ab83c | 9382 | swhash->hlist_refcount++; |
9ed6060d | 9383 | exit: |
b28ab83c | 9384 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9385 | |
9386 | return err; | |
9387 | } | |
9388 | ||
3b364d7b | 9389 | static int swevent_hlist_get(void) |
76e1d904 | 9390 | { |
3b364d7b | 9391 | int err, cpu, failed_cpu; |
76e1d904 | 9392 | |
a63fbed7 | 9393 | mutex_lock(&pmus_lock); |
76e1d904 | 9394 | for_each_possible_cpu(cpu) { |
3b364d7b | 9395 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9396 | if (err) { |
9397 | failed_cpu = cpu; | |
9398 | goto fail; | |
9399 | } | |
9400 | } | |
a63fbed7 | 9401 | mutex_unlock(&pmus_lock); |
76e1d904 | 9402 | return 0; |
9ed6060d | 9403 | fail: |
76e1d904 FW |
9404 | for_each_possible_cpu(cpu) { |
9405 | if (cpu == failed_cpu) | |
9406 | break; | |
3b364d7b | 9407 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9408 | } |
a63fbed7 | 9409 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9410 | return err; |
9411 | } | |
9412 | ||
c5905afb | 9413 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9414 | |
b0a873eb PZ |
9415 | static void sw_perf_event_destroy(struct perf_event *event) |
9416 | { | |
9417 | u64 event_id = event->attr.config; | |
95476b64 | 9418 | |
b0a873eb PZ |
9419 | WARN_ON(event->parent); |
9420 | ||
c5905afb | 9421 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9422 | swevent_hlist_put(); |
b0a873eb PZ |
9423 | } |
9424 | ||
9425 | static int perf_swevent_init(struct perf_event *event) | |
9426 | { | |
8176cced | 9427 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9428 | |
9429 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9430 | return -ENOENT; | |
9431 | ||
2481c5fa SE |
9432 | /* |
9433 | * no branch sampling for software events | |
9434 | */ | |
9435 | if (has_branch_stack(event)) | |
9436 | return -EOPNOTSUPP; | |
9437 | ||
b0a873eb PZ |
9438 | switch (event_id) { |
9439 | case PERF_COUNT_SW_CPU_CLOCK: | |
9440 | case PERF_COUNT_SW_TASK_CLOCK: | |
9441 | return -ENOENT; | |
9442 | ||
9443 | default: | |
9444 | break; | |
9445 | } | |
9446 | ||
ce677831 | 9447 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9448 | return -ENOENT; |
9449 | ||
9450 | if (!event->parent) { | |
9451 | int err; | |
9452 | ||
3b364d7b | 9453 | err = swevent_hlist_get(); |
b0a873eb PZ |
9454 | if (err) |
9455 | return err; | |
9456 | ||
c5905afb | 9457 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9458 | event->destroy = sw_perf_event_destroy; |
9459 | } | |
9460 | ||
9461 | return 0; | |
9462 | } | |
9463 | ||
9464 | static struct pmu perf_swevent = { | |
89a1e187 | 9465 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9466 | |
34f43927 PZ |
9467 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9468 | ||
b0a873eb | 9469 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9470 | .add = perf_swevent_add, |
9471 | .del = perf_swevent_del, | |
9472 | .start = perf_swevent_start, | |
9473 | .stop = perf_swevent_stop, | |
1c024eca | 9474 | .read = perf_swevent_read, |
1c024eca PZ |
9475 | }; |
9476 | ||
b0a873eb PZ |
9477 | #ifdef CONFIG_EVENT_TRACING |
9478 | ||
1c024eca PZ |
9479 | static int perf_tp_filter_match(struct perf_event *event, |
9480 | struct perf_sample_data *data) | |
9481 | { | |
7e3f977e | 9482 | void *record = data->raw->frag.data; |
1c024eca | 9483 | |
b71b437e PZ |
9484 | /* only top level events have filters set */ |
9485 | if (event->parent) | |
9486 | event = event->parent; | |
9487 | ||
1c024eca PZ |
9488 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9489 | return 1; | |
9490 | return 0; | |
9491 | } | |
9492 | ||
9493 | static int perf_tp_event_match(struct perf_event *event, | |
9494 | struct perf_sample_data *data, | |
9495 | struct pt_regs *regs) | |
9496 | { | |
a0f7d0f7 FW |
9497 | if (event->hw.state & PERF_HES_STOPPED) |
9498 | return 0; | |
580d607c | 9499 | /* |
9fd2e48b | 9500 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9501 | */ |
9fd2e48b | 9502 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9503 | return 0; |
9504 | ||
9505 | if (!perf_tp_filter_match(event, data)) | |
9506 | return 0; | |
9507 | ||
9508 | return 1; | |
9509 | } | |
9510 | ||
85b67bcb AS |
9511 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9512 | struct trace_event_call *call, u64 count, | |
9513 | struct pt_regs *regs, struct hlist_head *head, | |
9514 | struct task_struct *task) | |
9515 | { | |
e87c6bc3 | 9516 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9517 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9518 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9519 | perf_swevent_put_recursion_context(rctx); |
9520 | return; | |
9521 | } | |
9522 | } | |
9523 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9524 | rctx, task); |
85b67bcb AS |
9525 | } |
9526 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9527 | ||
1e1dcd93 | 9528 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9529 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9530 | struct task_struct *task) |
95476b64 FW |
9531 | { |
9532 | struct perf_sample_data data; | |
8fd0fbbe | 9533 | struct perf_event *event; |
1c024eca | 9534 | |
95476b64 | 9535 | struct perf_raw_record raw = { |
7e3f977e DB |
9536 | .frag = { |
9537 | .size = entry_size, | |
9538 | .data = record, | |
9539 | }, | |
95476b64 FW |
9540 | }; |
9541 | ||
1e1dcd93 | 9542 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9543 | data.raw = &raw; |
9544 | ||
1e1dcd93 AS |
9545 | perf_trace_buf_update(record, event_type); |
9546 | ||
8fd0fbbe | 9547 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9548 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9549 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9550 | } |
ecc55f84 | 9551 | |
e6dab5ff AV |
9552 | /* |
9553 | * If we got specified a target task, also iterate its context and | |
9554 | * deliver this event there too. | |
9555 | */ | |
9556 | if (task && task != current) { | |
9557 | struct perf_event_context *ctx; | |
9558 | struct trace_entry *entry = record; | |
9559 | ||
9560 | rcu_read_lock(); | |
9561 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9562 | if (!ctx) | |
9563 | goto unlock; | |
9564 | ||
9565 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9566 | if (event->cpu != smp_processor_id()) |
9567 | continue; | |
e6dab5ff AV |
9568 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9569 | continue; | |
9570 | if (event->attr.config != entry->type) | |
9571 | continue; | |
9572 | if (perf_tp_event_match(event, &data, regs)) | |
9573 | perf_swevent_event(event, count, &data, regs); | |
9574 | } | |
9575 | unlock: | |
9576 | rcu_read_unlock(); | |
9577 | } | |
9578 | ||
ecc55f84 | 9579 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9580 | } |
9581 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9582 | ||
cdd6c482 | 9583 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9584 | { |
1c024eca | 9585 | perf_trace_destroy(event); |
e077df4f PZ |
9586 | } |
9587 | ||
b0a873eb | 9588 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9589 | { |
76e1d904 FW |
9590 | int err; |
9591 | ||
b0a873eb PZ |
9592 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9593 | return -ENOENT; | |
9594 | ||
2481c5fa SE |
9595 | /* |
9596 | * no branch sampling for tracepoint events | |
9597 | */ | |
9598 | if (has_branch_stack(event)) | |
9599 | return -EOPNOTSUPP; | |
9600 | ||
1c024eca PZ |
9601 | err = perf_trace_init(event); |
9602 | if (err) | |
b0a873eb | 9603 | return err; |
e077df4f | 9604 | |
cdd6c482 | 9605 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9606 | |
b0a873eb PZ |
9607 | return 0; |
9608 | } | |
9609 | ||
9610 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9611 | .task_ctx_nr = perf_sw_context, |
9612 | ||
b0a873eb | 9613 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9614 | .add = perf_trace_add, |
9615 | .del = perf_trace_del, | |
9616 | .start = perf_swevent_start, | |
9617 | .stop = perf_swevent_stop, | |
b0a873eb | 9618 | .read = perf_swevent_read, |
b0a873eb PZ |
9619 | }; |
9620 | ||
33ea4b24 | 9621 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9622 | /* |
9623 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9624 | * The flags should match following PMU_FORMAT_ATTR(). | |
9625 | * | |
9626 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9627 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9628 | * |
9629 | * The following values specify a reference counter (or semaphore in the | |
9630 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9631 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9632 | * | |
9633 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9634 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9635 | */ |
9636 | enum perf_probe_config { | |
9637 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9638 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9639 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9640 | }; |
9641 | ||
9642 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9643 | #endif |
e12f03d7 | 9644 | |
a6ca88b2 SL |
9645 | #ifdef CONFIG_KPROBE_EVENTS |
9646 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9647 | &format_attr_retprobe.attr, |
9648 | NULL, | |
9649 | }; | |
9650 | ||
a6ca88b2 | 9651 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9652 | .name = "format", |
a6ca88b2 | 9653 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9654 | }; |
9655 | ||
a6ca88b2 SL |
9656 | static const struct attribute_group *kprobe_attr_groups[] = { |
9657 | &kprobe_format_group, | |
e12f03d7 SL |
9658 | NULL, |
9659 | }; | |
9660 | ||
9661 | static int perf_kprobe_event_init(struct perf_event *event); | |
9662 | static struct pmu perf_kprobe = { | |
9663 | .task_ctx_nr = perf_sw_context, | |
9664 | .event_init = perf_kprobe_event_init, | |
9665 | .add = perf_trace_add, | |
9666 | .del = perf_trace_del, | |
9667 | .start = perf_swevent_start, | |
9668 | .stop = perf_swevent_stop, | |
9669 | .read = perf_swevent_read, | |
a6ca88b2 | 9670 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9671 | }; |
9672 | ||
9673 | static int perf_kprobe_event_init(struct perf_event *event) | |
9674 | { | |
9675 | int err; | |
9676 | bool is_retprobe; | |
9677 | ||
9678 | if (event->attr.type != perf_kprobe.type) | |
9679 | return -ENOENT; | |
32e6e967 | 9680 | |
c9e0924e | 9681 | if (!perfmon_capable()) |
32e6e967 SL |
9682 | return -EACCES; |
9683 | ||
e12f03d7 SL |
9684 | /* |
9685 | * no branch sampling for probe events | |
9686 | */ | |
9687 | if (has_branch_stack(event)) | |
9688 | return -EOPNOTSUPP; | |
9689 | ||
9690 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9691 | err = perf_kprobe_init(event, is_retprobe); | |
9692 | if (err) | |
9693 | return err; | |
9694 | ||
9695 | event->destroy = perf_kprobe_destroy; | |
9696 | ||
9697 | return 0; | |
9698 | } | |
9699 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9700 | ||
33ea4b24 | 9701 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9702 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9703 | ||
9704 | static struct attribute *uprobe_attrs[] = { | |
9705 | &format_attr_retprobe.attr, | |
9706 | &format_attr_ref_ctr_offset.attr, | |
9707 | NULL, | |
9708 | }; | |
9709 | ||
9710 | static struct attribute_group uprobe_format_group = { | |
9711 | .name = "format", | |
9712 | .attrs = uprobe_attrs, | |
9713 | }; | |
9714 | ||
9715 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9716 | &uprobe_format_group, | |
9717 | NULL, | |
9718 | }; | |
9719 | ||
33ea4b24 SL |
9720 | static int perf_uprobe_event_init(struct perf_event *event); |
9721 | static struct pmu perf_uprobe = { | |
9722 | .task_ctx_nr = perf_sw_context, | |
9723 | .event_init = perf_uprobe_event_init, | |
9724 | .add = perf_trace_add, | |
9725 | .del = perf_trace_del, | |
9726 | .start = perf_swevent_start, | |
9727 | .stop = perf_swevent_stop, | |
9728 | .read = perf_swevent_read, | |
a6ca88b2 | 9729 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9730 | }; |
9731 | ||
9732 | static int perf_uprobe_event_init(struct perf_event *event) | |
9733 | { | |
9734 | int err; | |
a6ca88b2 | 9735 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9736 | bool is_retprobe; |
9737 | ||
9738 | if (event->attr.type != perf_uprobe.type) | |
9739 | return -ENOENT; | |
32e6e967 | 9740 | |
c9e0924e | 9741 | if (!perfmon_capable()) |
32e6e967 SL |
9742 | return -EACCES; |
9743 | ||
33ea4b24 SL |
9744 | /* |
9745 | * no branch sampling for probe events | |
9746 | */ | |
9747 | if (has_branch_stack(event)) | |
9748 | return -EOPNOTSUPP; | |
9749 | ||
9750 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9751 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9752 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9753 | if (err) |
9754 | return err; | |
9755 | ||
9756 | event->destroy = perf_uprobe_destroy; | |
9757 | ||
9758 | return 0; | |
9759 | } | |
9760 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9761 | ||
b0a873eb PZ |
9762 | static inline void perf_tp_register(void) |
9763 | { | |
2e80a82a | 9764 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9765 | #ifdef CONFIG_KPROBE_EVENTS |
9766 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9767 | #endif | |
33ea4b24 SL |
9768 | #ifdef CONFIG_UPROBE_EVENTS |
9769 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9770 | #endif | |
e077df4f | 9771 | } |
6fb2915d | 9772 | |
6fb2915d LZ |
9773 | static void perf_event_free_filter(struct perf_event *event) |
9774 | { | |
9775 | ftrace_profile_free_filter(event); | |
9776 | } | |
9777 | ||
aa6a5f3c AS |
9778 | #ifdef CONFIG_BPF_SYSCALL |
9779 | static void bpf_overflow_handler(struct perf_event *event, | |
9780 | struct perf_sample_data *data, | |
9781 | struct pt_regs *regs) | |
9782 | { | |
9783 | struct bpf_perf_event_data_kern ctx = { | |
9784 | .data = data, | |
7d9285e8 | 9785 | .event = event, |
aa6a5f3c AS |
9786 | }; |
9787 | int ret = 0; | |
9788 | ||
c895f6f7 | 9789 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9790 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9791 | goto out; | |
9792 | rcu_read_lock(); | |
88575199 | 9793 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9794 | rcu_read_unlock(); |
9795 | out: | |
9796 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9797 | if (!ret) |
9798 | return; | |
9799 | ||
9800 | event->orig_overflow_handler(event, data, regs); | |
9801 | } | |
9802 | ||
9803 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9804 | { | |
9805 | struct bpf_prog *prog; | |
9806 | ||
9807 | if (event->overflow_handler_context) | |
9808 | /* hw breakpoint or kernel counter */ | |
9809 | return -EINVAL; | |
9810 | ||
9811 | if (event->prog) | |
9812 | return -EEXIST; | |
9813 | ||
9814 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9815 | if (IS_ERR(prog)) | |
9816 | return PTR_ERR(prog); | |
9817 | ||
5d99cb2c SL |
9818 | if (event->attr.precise_ip && |
9819 | prog->call_get_stack && | |
9820 | (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY) || | |
9821 | event->attr.exclude_callchain_kernel || | |
9822 | event->attr.exclude_callchain_user)) { | |
9823 | /* | |
9824 | * On perf_event with precise_ip, calling bpf_get_stack() | |
9825 | * may trigger unwinder warnings and occasional crashes. | |
9826 | * bpf_get_[stack|stackid] works around this issue by using | |
9827 | * callchain attached to perf_sample_data. If the | |
9828 | * perf_event does not full (kernel and user) callchain | |
9829 | * attached to perf_sample_data, do not allow attaching BPF | |
9830 | * program that calls bpf_get_[stack|stackid]. | |
9831 | */ | |
9832 | bpf_prog_put(prog); | |
9833 | return -EPROTO; | |
9834 | } | |
9835 | ||
aa6a5f3c AS |
9836 | event->prog = prog; |
9837 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9838 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9839 | return 0; | |
9840 | } | |
9841 | ||
9842 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9843 | { | |
9844 | struct bpf_prog *prog = event->prog; | |
9845 | ||
9846 | if (!prog) | |
9847 | return; | |
9848 | ||
9849 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9850 | event->prog = NULL; | |
9851 | bpf_prog_put(prog); | |
9852 | } | |
9853 | #else | |
9854 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9855 | { | |
9856 | return -EOPNOTSUPP; | |
9857 | } | |
9858 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9859 | { | |
9860 | } | |
9861 | #endif | |
9862 | ||
e12f03d7 SL |
9863 | /* |
9864 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9865 | * with perf_event_open() | |
9866 | */ | |
9867 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9868 | { | |
9869 | if (event->pmu == &perf_tracepoint) | |
9870 | return true; | |
9871 | #ifdef CONFIG_KPROBE_EVENTS | |
9872 | if (event->pmu == &perf_kprobe) | |
9873 | return true; | |
33ea4b24 SL |
9874 | #endif |
9875 | #ifdef CONFIG_UPROBE_EVENTS | |
9876 | if (event->pmu == &perf_uprobe) | |
9877 | return true; | |
e12f03d7 SL |
9878 | #endif |
9879 | return false; | |
9880 | } | |
9881 | ||
2541517c AS |
9882 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9883 | { | |
cf5f5cea | 9884 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9885 | struct bpf_prog *prog; |
e87c6bc3 | 9886 | int ret; |
2541517c | 9887 | |
e12f03d7 | 9888 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9889 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9890 | |
98b5c2c6 AS |
9891 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9892 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9893 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9894 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9895 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9896 | return -EINVAL; |
9897 | ||
9898 | prog = bpf_prog_get(prog_fd); | |
9899 | if (IS_ERR(prog)) | |
9900 | return PTR_ERR(prog); | |
9901 | ||
98b5c2c6 | 9902 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9903 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9904 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9905 | /* valid fd, but invalid bpf program type */ |
9906 | bpf_prog_put(prog); | |
9907 | return -EINVAL; | |
9908 | } | |
9909 | ||
9802d865 JB |
9910 | /* Kprobe override only works for kprobes, not uprobes. */ |
9911 | if (prog->kprobe_override && | |
9912 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9913 | bpf_prog_put(prog); | |
9914 | return -EINVAL; | |
9915 | } | |
9916 | ||
cf5f5cea | 9917 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9918 | int off = trace_event_get_offsets(event->tp_event); |
9919 | ||
9920 | if (prog->aux->max_ctx_offset > off) { | |
9921 | bpf_prog_put(prog); | |
9922 | return -EACCES; | |
9923 | } | |
9924 | } | |
2541517c | 9925 | |
e87c6bc3 YS |
9926 | ret = perf_event_attach_bpf_prog(event, prog); |
9927 | if (ret) | |
9928 | bpf_prog_put(prog); | |
9929 | return ret; | |
2541517c AS |
9930 | } |
9931 | ||
9932 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9933 | { | |
e12f03d7 | 9934 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9935 | perf_event_free_bpf_handler(event); |
2541517c | 9936 | return; |
2541517c | 9937 | } |
e87c6bc3 | 9938 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9939 | } |
9940 | ||
e077df4f | 9941 | #else |
6fb2915d | 9942 | |
b0a873eb | 9943 | static inline void perf_tp_register(void) |
e077df4f | 9944 | { |
e077df4f | 9945 | } |
6fb2915d | 9946 | |
6fb2915d LZ |
9947 | static void perf_event_free_filter(struct perf_event *event) |
9948 | { | |
9949 | } | |
9950 | ||
2541517c AS |
9951 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9952 | { | |
9953 | return -ENOENT; | |
9954 | } | |
9955 | ||
9956 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9957 | { | |
9958 | } | |
07b139c8 | 9959 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9960 | |
24f1e32c | 9961 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9962 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9963 | { |
f5ffe02e FW |
9964 | struct perf_sample_data sample; |
9965 | struct pt_regs *regs = data; | |
9966 | ||
fd0d000b | 9967 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9968 | |
a4eaf7f1 | 9969 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9970 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9971 | } |
9972 | #endif | |
9973 | ||
375637bc AS |
9974 | /* |
9975 | * Allocate a new address filter | |
9976 | */ | |
9977 | static struct perf_addr_filter * | |
9978 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9979 | { | |
9980 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9981 | struct perf_addr_filter *filter; | |
9982 | ||
9983 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9984 | if (!filter) | |
9985 | return NULL; | |
9986 | ||
9987 | INIT_LIST_HEAD(&filter->entry); | |
9988 | list_add_tail(&filter->entry, filters); | |
9989 | ||
9990 | return filter; | |
9991 | } | |
9992 | ||
9993 | static void free_filters_list(struct list_head *filters) | |
9994 | { | |
9995 | struct perf_addr_filter *filter, *iter; | |
9996 | ||
9997 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9998 | path_put(&filter->path); |
375637bc AS |
9999 | list_del(&filter->entry); |
10000 | kfree(filter); | |
10001 | } | |
10002 | } | |
10003 | ||
10004 | /* | |
10005 | * Free existing address filters and optionally install new ones | |
10006 | */ | |
10007 | static void perf_addr_filters_splice(struct perf_event *event, | |
10008 | struct list_head *head) | |
10009 | { | |
10010 | unsigned long flags; | |
10011 | LIST_HEAD(list); | |
10012 | ||
10013 | if (!has_addr_filter(event)) | |
10014 | return; | |
10015 | ||
10016 | /* don't bother with children, they don't have their own filters */ | |
10017 | if (event->parent) | |
10018 | return; | |
10019 | ||
10020 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
10021 | ||
10022 | list_splice_init(&event->addr_filters.list, &list); | |
10023 | if (head) | |
10024 | list_splice(head, &event->addr_filters.list); | |
10025 | ||
10026 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
10027 | ||
10028 | free_filters_list(&list); | |
10029 | } | |
10030 | ||
10031 | /* | |
10032 | * Scan through mm's vmas and see if one of them matches the | |
10033 | * @filter; if so, adjust filter's address range. | |
c1e8d7c6 | 10034 | * Called with mm::mmap_lock down for reading. |
375637bc | 10035 | */ |
c60f83b8 AS |
10036 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
10037 | struct mm_struct *mm, | |
10038 | struct perf_addr_filter_range *fr) | |
375637bc AS |
10039 | { |
10040 | struct vm_area_struct *vma; | |
10041 | ||
10042 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 10043 | if (!vma->vm_file) |
375637bc AS |
10044 | continue; |
10045 | ||
c60f83b8 AS |
10046 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
10047 | return; | |
375637bc | 10048 | } |
375637bc AS |
10049 | } |
10050 | ||
10051 | /* | |
10052 | * Update event's address range filters based on the | |
10053 | * task's existing mappings, if any. | |
10054 | */ | |
10055 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
10056 | { | |
10057 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10058 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
10059 | struct perf_addr_filter *filter; | |
10060 | struct mm_struct *mm = NULL; | |
10061 | unsigned int count = 0; | |
10062 | unsigned long flags; | |
10063 | ||
10064 | /* | |
10065 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
10066 | * will stop on the parent's child_mutex that our caller is also holding | |
10067 | */ | |
10068 | if (task == TASK_TOMBSTONE) | |
10069 | return; | |
10070 | ||
52a44f83 AS |
10071 | if (ifh->nr_file_filters) { |
10072 | mm = get_task_mm(event->ctx->task); | |
10073 | if (!mm) | |
10074 | goto restart; | |
375637bc | 10075 | |
d8ed45c5 | 10076 | mmap_read_lock(mm); |
52a44f83 | 10077 | } |
375637bc AS |
10078 | |
10079 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
10080 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
10081 | if (filter->path.dentry) { |
10082 | /* | |
10083 | * Adjust base offset if the filter is associated to a | |
10084 | * binary that needs to be mapped: | |
10085 | */ | |
10086 | event->addr_filter_ranges[count].start = 0; | |
10087 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 10088 | |
c60f83b8 | 10089 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
10090 | } else { |
10091 | event->addr_filter_ranges[count].start = filter->offset; | |
10092 | event->addr_filter_ranges[count].size = filter->size; | |
10093 | } | |
375637bc AS |
10094 | |
10095 | count++; | |
10096 | } | |
10097 | ||
10098 | event->addr_filters_gen++; | |
10099 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
10100 | ||
52a44f83 | 10101 | if (ifh->nr_file_filters) { |
d8ed45c5 | 10102 | mmap_read_unlock(mm); |
375637bc | 10103 | |
52a44f83 AS |
10104 | mmput(mm); |
10105 | } | |
375637bc AS |
10106 | |
10107 | restart: | |
767ae086 | 10108 | perf_event_stop(event, 1); |
375637bc AS |
10109 | } |
10110 | ||
10111 | /* | |
10112 | * Address range filtering: limiting the data to certain | |
10113 | * instruction address ranges. Filters are ioctl()ed to us from | |
10114 | * userspace as ascii strings. | |
10115 | * | |
10116 | * Filter string format: | |
10117 | * | |
10118 | * ACTION RANGE_SPEC | |
10119 | * where ACTION is one of the | |
10120 | * * "filter": limit the trace to this region | |
10121 | * * "start": start tracing from this address | |
10122 | * * "stop": stop tracing at this address/region; | |
10123 | * RANGE_SPEC is | |
10124 | * * for kernel addresses: <start address>[/<size>] | |
10125 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
10126 | * | |
6ed70cf3 AS |
10127 | * if <size> is not specified or is zero, the range is treated as a single |
10128 | * address; not valid for ACTION=="filter". | |
375637bc AS |
10129 | */ |
10130 | enum { | |
e96271f3 | 10131 | IF_ACT_NONE = -1, |
375637bc AS |
10132 | IF_ACT_FILTER, |
10133 | IF_ACT_START, | |
10134 | IF_ACT_STOP, | |
10135 | IF_SRC_FILE, | |
10136 | IF_SRC_KERNEL, | |
10137 | IF_SRC_FILEADDR, | |
10138 | IF_SRC_KERNELADDR, | |
10139 | }; | |
10140 | ||
10141 | enum { | |
10142 | IF_STATE_ACTION = 0, | |
10143 | IF_STATE_SOURCE, | |
10144 | IF_STATE_END, | |
10145 | }; | |
10146 | ||
10147 | static const match_table_t if_tokens = { | |
10148 | { IF_ACT_FILTER, "filter" }, | |
10149 | { IF_ACT_START, "start" }, | |
10150 | { IF_ACT_STOP, "stop" }, | |
10151 | { IF_SRC_FILE, "%u/%u@%s" }, | |
10152 | { IF_SRC_KERNEL, "%u/%u" }, | |
10153 | { IF_SRC_FILEADDR, "%u@%s" }, | |
10154 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 10155 | { IF_ACT_NONE, NULL }, |
375637bc AS |
10156 | }; |
10157 | ||
10158 | /* | |
10159 | * Address filter string parser | |
10160 | */ | |
10161 | static int | |
10162 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
10163 | struct list_head *filters) | |
10164 | { | |
10165 | struct perf_addr_filter *filter = NULL; | |
10166 | char *start, *orig, *filename = NULL; | |
375637bc AS |
10167 | substring_t args[MAX_OPT_ARGS]; |
10168 | int state = IF_STATE_ACTION, token; | |
10169 | unsigned int kernel = 0; | |
10170 | int ret = -EINVAL; | |
10171 | ||
10172 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
10173 | if (!fstr) | |
10174 | return -ENOMEM; | |
10175 | ||
10176 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
10177 | static const enum perf_addr_filter_action_t actions[] = { |
10178 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
10179 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
10180 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
10181 | }; | |
375637bc AS |
10182 | ret = -EINVAL; |
10183 | ||
10184 | if (!*start) | |
10185 | continue; | |
10186 | ||
10187 | /* filter definition begins */ | |
10188 | if (state == IF_STATE_ACTION) { | |
10189 | filter = perf_addr_filter_new(event, filters); | |
10190 | if (!filter) | |
10191 | goto fail; | |
10192 | } | |
10193 | ||
10194 | token = match_token(start, if_tokens, args); | |
10195 | switch (token) { | |
10196 | case IF_ACT_FILTER: | |
10197 | case IF_ACT_START: | |
375637bc AS |
10198 | case IF_ACT_STOP: |
10199 | if (state != IF_STATE_ACTION) | |
10200 | goto fail; | |
10201 | ||
6ed70cf3 | 10202 | filter->action = actions[token]; |
375637bc AS |
10203 | state = IF_STATE_SOURCE; |
10204 | break; | |
10205 | ||
10206 | case IF_SRC_KERNELADDR: | |
10207 | case IF_SRC_KERNEL: | |
10208 | kernel = 1; | |
df561f66 | 10209 | fallthrough; |
375637bc AS |
10210 | |
10211 | case IF_SRC_FILEADDR: | |
10212 | case IF_SRC_FILE: | |
10213 | if (state != IF_STATE_SOURCE) | |
10214 | goto fail; | |
10215 | ||
375637bc AS |
10216 | *args[0].to = 0; |
10217 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
10218 | if (ret) | |
10219 | goto fail; | |
10220 | ||
6ed70cf3 | 10221 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
10222 | *args[1].to = 0; |
10223 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
10224 | if (ret) | |
10225 | goto fail; | |
10226 | } | |
10227 | ||
4059ffd0 | 10228 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 10229 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 | 10230 | |
7bdb157c | 10231 | kfree(filename); |
4059ffd0 | 10232 | filename = match_strdup(&args[fpos]); |
375637bc AS |
10233 | if (!filename) { |
10234 | ret = -ENOMEM; | |
10235 | goto fail; | |
10236 | } | |
10237 | } | |
10238 | ||
10239 | state = IF_STATE_END; | |
10240 | break; | |
10241 | ||
10242 | default: | |
10243 | goto fail; | |
10244 | } | |
10245 | ||
10246 | /* | |
10247 | * Filter definition is fully parsed, validate and install it. | |
10248 | * Make sure that it doesn't contradict itself or the event's | |
10249 | * attribute. | |
10250 | */ | |
10251 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 10252 | ret = -EINVAL; |
375637bc AS |
10253 | if (kernel && event->attr.exclude_kernel) |
10254 | goto fail; | |
10255 | ||
6ed70cf3 AS |
10256 | /* |
10257 | * ACTION "filter" must have a non-zero length region | |
10258 | * specified. | |
10259 | */ | |
10260 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
10261 | !filter->size) | |
10262 | goto fail; | |
10263 | ||
375637bc AS |
10264 | if (!kernel) { |
10265 | if (!filename) | |
10266 | goto fail; | |
10267 | ||
6ce77bfd AS |
10268 | /* |
10269 | * For now, we only support file-based filters | |
10270 | * in per-task events; doing so for CPU-wide | |
10271 | * events requires additional context switching | |
10272 | * trickery, since same object code will be | |
10273 | * mapped at different virtual addresses in | |
10274 | * different processes. | |
10275 | */ | |
10276 | ret = -EOPNOTSUPP; | |
10277 | if (!event->ctx->task) | |
7bdb157c | 10278 | goto fail; |
6ce77bfd | 10279 | |
375637bc | 10280 | /* look up the path and grab its inode */ |
9511bce9 SL |
10281 | ret = kern_path(filename, LOOKUP_FOLLOW, |
10282 | &filter->path); | |
375637bc | 10283 | if (ret) |
7bdb157c | 10284 | goto fail; |
375637bc AS |
10285 | |
10286 | ret = -EINVAL; | |
9511bce9 SL |
10287 | if (!filter->path.dentry || |
10288 | !S_ISREG(d_inode(filter->path.dentry) | |
10289 | ->i_mode)) | |
375637bc | 10290 | goto fail; |
6ce77bfd AS |
10291 | |
10292 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
10293 | } |
10294 | ||
10295 | /* ready to consume more filters */ | |
10296 | state = IF_STATE_ACTION; | |
10297 | filter = NULL; | |
10298 | } | |
10299 | } | |
10300 | ||
10301 | if (state != IF_STATE_ACTION) | |
10302 | goto fail; | |
10303 | ||
7bdb157c | 10304 | kfree(filename); |
375637bc AS |
10305 | kfree(orig); |
10306 | ||
10307 | return 0; | |
10308 | ||
375637bc | 10309 | fail: |
7bdb157c | 10310 | kfree(filename); |
375637bc AS |
10311 | free_filters_list(filters); |
10312 | kfree(orig); | |
10313 | ||
10314 | return ret; | |
10315 | } | |
10316 | ||
10317 | static int | |
10318 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10319 | { | |
10320 | LIST_HEAD(filters); | |
10321 | int ret; | |
10322 | ||
10323 | /* | |
10324 | * Since this is called in perf_ioctl() path, we're already holding | |
10325 | * ctx::mutex. | |
10326 | */ | |
10327 | lockdep_assert_held(&event->ctx->mutex); | |
10328 | ||
10329 | if (WARN_ON_ONCE(event->parent)) | |
10330 | return -EINVAL; | |
10331 | ||
375637bc AS |
10332 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10333 | if (ret) | |
6ce77bfd | 10334 | goto fail_clear_files; |
375637bc AS |
10335 | |
10336 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10337 | if (ret) |
10338 | goto fail_free_filters; | |
375637bc AS |
10339 | |
10340 | /* remove existing filters, if any */ | |
10341 | perf_addr_filters_splice(event, &filters); | |
10342 | ||
10343 | /* install new filters */ | |
10344 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10345 | ||
6ce77bfd AS |
10346 | return ret; |
10347 | ||
10348 | fail_free_filters: | |
10349 | free_filters_list(&filters); | |
10350 | ||
10351 | fail_clear_files: | |
10352 | event->addr_filters.nr_file_filters = 0; | |
10353 | ||
375637bc AS |
10354 | return ret; |
10355 | } | |
10356 | ||
c796bbbe AS |
10357 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10358 | { | |
c796bbbe | 10359 | int ret = -EINVAL; |
e12f03d7 | 10360 | char *filter_str; |
c796bbbe AS |
10361 | |
10362 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10363 | if (IS_ERR(filter_str)) | |
10364 | return PTR_ERR(filter_str); | |
10365 | ||
e12f03d7 SL |
10366 | #ifdef CONFIG_EVENT_TRACING |
10367 | if (perf_event_is_tracing(event)) { | |
10368 | struct perf_event_context *ctx = event->ctx; | |
10369 | ||
10370 | /* | |
10371 | * Beware, here be dragons!! | |
10372 | * | |
10373 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10374 | * the tracepoint stuff does not actually need it. So | |
10375 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10376 | * already have a reference on ctx. | |
10377 | * | |
10378 | * This can result in event getting moved to a different ctx, | |
10379 | * but that does not affect the tracepoint state. | |
10380 | */ | |
10381 | mutex_unlock(&ctx->mutex); | |
10382 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10383 | mutex_lock(&ctx->mutex); | |
10384 | } else | |
10385 | #endif | |
10386 | if (has_addr_filter(event)) | |
375637bc | 10387 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10388 | |
10389 | kfree(filter_str); | |
10390 | return ret; | |
10391 | } | |
10392 | ||
b0a873eb PZ |
10393 | /* |
10394 | * hrtimer based swevent callback | |
10395 | */ | |
f29ac756 | 10396 | |
b0a873eb | 10397 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10398 | { |
b0a873eb PZ |
10399 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10400 | struct perf_sample_data data; | |
10401 | struct pt_regs *regs; | |
10402 | struct perf_event *event; | |
10403 | u64 period; | |
f29ac756 | 10404 | |
b0a873eb | 10405 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10406 | |
10407 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10408 | return HRTIMER_NORESTART; | |
10409 | ||
b0a873eb | 10410 | event->pmu->read(event); |
f344011c | 10411 | |
fd0d000b | 10412 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10413 | regs = get_irq_regs(); |
10414 | ||
10415 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10416 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10417 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10418 | ret = HRTIMER_NORESTART; |
10419 | } | |
24f1e32c | 10420 | |
b0a873eb PZ |
10421 | period = max_t(u64, 10000, event->hw.sample_period); |
10422 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10423 | |
b0a873eb | 10424 | return ret; |
f29ac756 PZ |
10425 | } |
10426 | ||
b0a873eb | 10427 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10428 | { |
b0a873eb | 10429 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10430 | s64 period; |
10431 | ||
10432 | if (!is_sampling_event(event)) | |
10433 | return; | |
f5ffe02e | 10434 | |
5d508e82 FBH |
10435 | period = local64_read(&hwc->period_left); |
10436 | if (period) { | |
10437 | if (period < 0) | |
10438 | period = 10000; | |
fa407f35 | 10439 | |
5d508e82 FBH |
10440 | local64_set(&hwc->period_left, 0); |
10441 | } else { | |
10442 | period = max_t(u64, 10000, hwc->sample_period); | |
10443 | } | |
3497d206 | 10444 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10445 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10446 | } |
b0a873eb PZ |
10447 | |
10448 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10449 | { |
b0a873eb PZ |
10450 | struct hw_perf_event *hwc = &event->hw; |
10451 | ||
6c7e550f | 10452 | if (is_sampling_event(event)) { |
b0a873eb | 10453 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10454 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10455 | |
10456 | hrtimer_cancel(&hwc->hrtimer); | |
10457 | } | |
24f1e32c FW |
10458 | } |
10459 | ||
ba3dd36c PZ |
10460 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10461 | { | |
10462 | struct hw_perf_event *hwc = &event->hw; | |
10463 | ||
10464 | if (!is_sampling_event(event)) | |
10465 | return; | |
10466 | ||
30f9028b | 10467 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10468 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10469 | ||
10470 | /* | |
10471 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10472 | * mapping and avoid the whole period adjust feedback stuff. | |
10473 | */ | |
10474 | if (event->attr.freq) { | |
10475 | long freq = event->attr.sample_freq; | |
10476 | ||
10477 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10478 | hwc->sample_period = event->attr.sample_period; | |
10479 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10480 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10481 | event->attr.freq = 0; |
10482 | } | |
10483 | } | |
10484 | ||
b0a873eb PZ |
10485 | /* |
10486 | * Software event: cpu wall time clock | |
10487 | */ | |
10488 | ||
10489 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10490 | { |
b0a873eb PZ |
10491 | s64 prev; |
10492 | u64 now; | |
10493 | ||
a4eaf7f1 | 10494 | now = local_clock(); |
b0a873eb PZ |
10495 | prev = local64_xchg(&event->hw.prev_count, now); |
10496 | local64_add(now - prev, &event->count); | |
24f1e32c | 10497 | } |
24f1e32c | 10498 | |
a4eaf7f1 | 10499 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10500 | { |
a4eaf7f1 | 10501 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10502 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10503 | } |
10504 | ||
a4eaf7f1 | 10505 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10506 | { |
b0a873eb PZ |
10507 | perf_swevent_cancel_hrtimer(event); |
10508 | cpu_clock_event_update(event); | |
10509 | } | |
f29ac756 | 10510 | |
a4eaf7f1 PZ |
10511 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10512 | { | |
10513 | if (flags & PERF_EF_START) | |
10514 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10515 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10516 | |
10517 | return 0; | |
10518 | } | |
10519 | ||
10520 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10521 | { | |
10522 | cpu_clock_event_stop(event, flags); | |
10523 | } | |
10524 | ||
b0a873eb PZ |
10525 | static void cpu_clock_event_read(struct perf_event *event) |
10526 | { | |
10527 | cpu_clock_event_update(event); | |
10528 | } | |
f344011c | 10529 | |
b0a873eb PZ |
10530 | static int cpu_clock_event_init(struct perf_event *event) |
10531 | { | |
10532 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10533 | return -ENOENT; | |
10534 | ||
10535 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10536 | return -ENOENT; | |
10537 | ||
2481c5fa SE |
10538 | /* |
10539 | * no branch sampling for software events | |
10540 | */ | |
10541 | if (has_branch_stack(event)) | |
10542 | return -EOPNOTSUPP; | |
10543 | ||
ba3dd36c PZ |
10544 | perf_swevent_init_hrtimer(event); |
10545 | ||
b0a873eb | 10546 | return 0; |
f29ac756 PZ |
10547 | } |
10548 | ||
b0a873eb | 10549 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10550 | .task_ctx_nr = perf_sw_context, |
10551 | ||
34f43927 PZ |
10552 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10553 | ||
b0a873eb | 10554 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10555 | .add = cpu_clock_event_add, |
10556 | .del = cpu_clock_event_del, | |
10557 | .start = cpu_clock_event_start, | |
10558 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10559 | .read = cpu_clock_event_read, |
10560 | }; | |
10561 | ||
10562 | /* | |
10563 | * Software event: task time clock | |
10564 | */ | |
10565 | ||
10566 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10567 | { |
b0a873eb PZ |
10568 | u64 prev; |
10569 | s64 delta; | |
5c92d124 | 10570 | |
b0a873eb PZ |
10571 | prev = local64_xchg(&event->hw.prev_count, now); |
10572 | delta = now - prev; | |
10573 | local64_add(delta, &event->count); | |
10574 | } | |
5c92d124 | 10575 | |
a4eaf7f1 | 10576 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10577 | { |
a4eaf7f1 | 10578 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10579 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10580 | } |
10581 | ||
a4eaf7f1 | 10582 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10583 | { |
10584 | perf_swevent_cancel_hrtimer(event); | |
10585 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10586 | } |
10587 | ||
10588 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10589 | { | |
10590 | if (flags & PERF_EF_START) | |
10591 | task_clock_event_start(event, flags); | |
6a694a60 | 10592 | perf_event_update_userpage(event); |
b0a873eb | 10593 | |
a4eaf7f1 PZ |
10594 | return 0; |
10595 | } | |
10596 | ||
10597 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10598 | { | |
10599 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10600 | } |
10601 | ||
10602 | static void task_clock_event_read(struct perf_event *event) | |
10603 | { | |
768a06e2 PZ |
10604 | u64 now = perf_clock(); |
10605 | u64 delta = now - event->ctx->timestamp; | |
10606 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10607 | |
10608 | task_clock_event_update(event, time); | |
10609 | } | |
10610 | ||
10611 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10612 | { |
b0a873eb PZ |
10613 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10614 | return -ENOENT; | |
10615 | ||
10616 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10617 | return -ENOENT; | |
10618 | ||
2481c5fa SE |
10619 | /* |
10620 | * no branch sampling for software events | |
10621 | */ | |
10622 | if (has_branch_stack(event)) | |
10623 | return -EOPNOTSUPP; | |
10624 | ||
ba3dd36c PZ |
10625 | perf_swevent_init_hrtimer(event); |
10626 | ||
b0a873eb | 10627 | return 0; |
6fb2915d LZ |
10628 | } |
10629 | ||
b0a873eb | 10630 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10631 | .task_ctx_nr = perf_sw_context, |
10632 | ||
34f43927 PZ |
10633 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10634 | ||
b0a873eb | 10635 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10636 | .add = task_clock_event_add, |
10637 | .del = task_clock_event_del, | |
10638 | .start = task_clock_event_start, | |
10639 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10640 | .read = task_clock_event_read, |
10641 | }; | |
6fb2915d | 10642 | |
ad5133b7 | 10643 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10644 | { |
e077df4f | 10645 | } |
6fb2915d | 10646 | |
fbbe0701 SB |
10647 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10648 | { | |
10649 | } | |
10650 | ||
ad5133b7 | 10651 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10652 | { |
ad5133b7 | 10653 | return 0; |
6fb2915d LZ |
10654 | } |
10655 | ||
81ec3f3c JO |
10656 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10657 | { | |
10658 | return 0; | |
10659 | } | |
10660 | ||
18ab2cd3 | 10661 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10662 | |
10663 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10664 | { |
fbbe0701 SB |
10665 | __this_cpu_write(nop_txn_flags, flags); |
10666 | ||
10667 | if (flags & ~PERF_PMU_TXN_ADD) | |
10668 | return; | |
10669 | ||
ad5133b7 | 10670 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10671 | } |
10672 | ||
ad5133b7 PZ |
10673 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10674 | { | |
fbbe0701 SB |
10675 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10676 | ||
10677 | __this_cpu_write(nop_txn_flags, 0); | |
10678 | ||
10679 | if (flags & ~PERF_PMU_TXN_ADD) | |
10680 | return 0; | |
10681 | ||
ad5133b7 PZ |
10682 | perf_pmu_enable(pmu); |
10683 | return 0; | |
10684 | } | |
e077df4f | 10685 | |
ad5133b7 | 10686 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10687 | { |
fbbe0701 SB |
10688 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10689 | ||
10690 | __this_cpu_write(nop_txn_flags, 0); | |
10691 | ||
10692 | if (flags & ~PERF_PMU_TXN_ADD) | |
10693 | return; | |
10694 | ||
ad5133b7 | 10695 | perf_pmu_enable(pmu); |
24f1e32c FW |
10696 | } |
10697 | ||
35edc2a5 PZ |
10698 | static int perf_event_idx_default(struct perf_event *event) |
10699 | { | |
c719f560 | 10700 | return 0; |
35edc2a5 PZ |
10701 | } |
10702 | ||
8dc85d54 PZ |
10703 | /* |
10704 | * Ensures all contexts with the same task_ctx_nr have the same | |
10705 | * pmu_cpu_context too. | |
10706 | */ | |
9e317041 | 10707 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10708 | { |
8dc85d54 | 10709 | struct pmu *pmu; |
b326e956 | 10710 | |
8dc85d54 PZ |
10711 | if (ctxn < 0) |
10712 | return NULL; | |
24f1e32c | 10713 | |
8dc85d54 PZ |
10714 | list_for_each_entry(pmu, &pmus, entry) { |
10715 | if (pmu->task_ctx_nr == ctxn) | |
10716 | return pmu->pmu_cpu_context; | |
10717 | } | |
24f1e32c | 10718 | |
8dc85d54 | 10719 | return NULL; |
24f1e32c FW |
10720 | } |
10721 | ||
51676957 PZ |
10722 | static void free_pmu_context(struct pmu *pmu) |
10723 | { | |
df0062b2 WD |
10724 | /* |
10725 | * Static contexts such as perf_sw_context have a global lifetime | |
10726 | * and may be shared between different PMUs. Avoid freeing them | |
10727 | * when a single PMU is going away. | |
10728 | */ | |
10729 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10730 | return; | |
10731 | ||
51676957 | 10732 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10733 | } |
6e855cd4 AS |
10734 | |
10735 | /* | |
10736 | * Let userspace know that this PMU supports address range filtering: | |
10737 | */ | |
10738 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10739 | struct device_attribute *attr, | |
10740 | char *page) | |
10741 | { | |
10742 | struct pmu *pmu = dev_get_drvdata(dev); | |
10743 | ||
10744 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10745 | } | |
10746 | DEVICE_ATTR_RO(nr_addr_filters); | |
10747 | ||
2e80a82a | 10748 | static struct idr pmu_idr; |
d6d020e9 | 10749 | |
abe43400 PZ |
10750 | static ssize_t |
10751 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10752 | { | |
10753 | struct pmu *pmu = dev_get_drvdata(dev); | |
10754 | ||
10755 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10756 | } | |
90826ca7 | 10757 | static DEVICE_ATTR_RO(type); |
abe43400 | 10758 | |
62b85639 SE |
10759 | static ssize_t |
10760 | perf_event_mux_interval_ms_show(struct device *dev, | |
10761 | struct device_attribute *attr, | |
10762 | char *page) | |
10763 | { | |
10764 | struct pmu *pmu = dev_get_drvdata(dev); | |
10765 | ||
10766 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10767 | } | |
10768 | ||
272325c4 PZ |
10769 | static DEFINE_MUTEX(mux_interval_mutex); |
10770 | ||
62b85639 SE |
10771 | static ssize_t |
10772 | perf_event_mux_interval_ms_store(struct device *dev, | |
10773 | struct device_attribute *attr, | |
10774 | const char *buf, size_t count) | |
10775 | { | |
10776 | struct pmu *pmu = dev_get_drvdata(dev); | |
10777 | int timer, cpu, ret; | |
10778 | ||
10779 | ret = kstrtoint(buf, 0, &timer); | |
10780 | if (ret) | |
10781 | return ret; | |
10782 | ||
10783 | if (timer < 1) | |
10784 | return -EINVAL; | |
10785 | ||
10786 | /* same value, noting to do */ | |
10787 | if (timer == pmu->hrtimer_interval_ms) | |
10788 | return count; | |
10789 | ||
272325c4 | 10790 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10791 | pmu->hrtimer_interval_ms = timer; |
10792 | ||
10793 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10794 | cpus_read_lock(); |
272325c4 | 10795 | for_each_online_cpu(cpu) { |
62b85639 SE |
10796 | struct perf_cpu_context *cpuctx; |
10797 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10798 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10799 | ||
272325c4 PZ |
10800 | cpu_function_call(cpu, |
10801 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10802 | } |
a63fbed7 | 10803 | cpus_read_unlock(); |
272325c4 | 10804 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10805 | |
10806 | return count; | |
10807 | } | |
90826ca7 | 10808 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10809 | |
90826ca7 GKH |
10810 | static struct attribute *pmu_dev_attrs[] = { |
10811 | &dev_attr_type.attr, | |
10812 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10813 | NULL, | |
abe43400 | 10814 | }; |
90826ca7 | 10815 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10816 | |
10817 | static int pmu_bus_running; | |
10818 | static struct bus_type pmu_bus = { | |
10819 | .name = "event_source", | |
90826ca7 | 10820 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10821 | }; |
10822 | ||
10823 | static void pmu_dev_release(struct device *dev) | |
10824 | { | |
10825 | kfree(dev); | |
10826 | } | |
10827 | ||
10828 | static int pmu_dev_alloc(struct pmu *pmu) | |
10829 | { | |
10830 | int ret = -ENOMEM; | |
10831 | ||
10832 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10833 | if (!pmu->dev) | |
10834 | goto out; | |
10835 | ||
0c9d42ed | 10836 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10837 | device_initialize(pmu->dev); |
10838 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10839 | if (ret) | |
10840 | goto free_dev; | |
10841 | ||
10842 | dev_set_drvdata(pmu->dev, pmu); | |
10843 | pmu->dev->bus = &pmu_bus; | |
10844 | pmu->dev->release = pmu_dev_release; | |
10845 | ret = device_add(pmu->dev); | |
10846 | if (ret) | |
10847 | goto free_dev; | |
10848 | ||
6e855cd4 AS |
10849 | /* For PMUs with address filters, throw in an extra attribute: */ |
10850 | if (pmu->nr_addr_filters) | |
10851 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10852 | ||
10853 | if (ret) | |
10854 | goto del_dev; | |
10855 | ||
f3a3a825 JO |
10856 | if (pmu->attr_update) |
10857 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10858 | ||
10859 | if (ret) | |
10860 | goto del_dev; | |
10861 | ||
abe43400 PZ |
10862 | out: |
10863 | return ret; | |
10864 | ||
6e855cd4 AS |
10865 | del_dev: |
10866 | device_del(pmu->dev); | |
10867 | ||
abe43400 PZ |
10868 | free_dev: |
10869 | put_device(pmu->dev); | |
10870 | goto out; | |
10871 | } | |
10872 | ||
547e9fd7 | 10873 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10874 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10875 | |
03d8e80b | 10876 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10877 | { |
66d258c5 | 10878 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10879 | |
b0a873eb | 10880 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10881 | ret = -ENOMEM; |
10882 | pmu->pmu_disable_count = alloc_percpu(int); | |
10883 | if (!pmu->pmu_disable_count) | |
10884 | goto unlock; | |
f29ac756 | 10885 | |
2e80a82a PZ |
10886 | pmu->type = -1; |
10887 | if (!name) | |
10888 | goto skip_type; | |
10889 | pmu->name = name; | |
10890 | ||
66d258c5 PZ |
10891 | if (type != PERF_TYPE_SOFTWARE) { |
10892 | if (type >= 0) | |
10893 | max = type; | |
10894 | ||
10895 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10896 | if (ret < 0) | |
2e80a82a | 10897 | goto free_pdc; |
66d258c5 PZ |
10898 | |
10899 | WARN_ON(type >= 0 && ret != type); | |
10900 | ||
10901 | type = ret; | |
2e80a82a PZ |
10902 | } |
10903 | pmu->type = type; | |
10904 | ||
abe43400 PZ |
10905 | if (pmu_bus_running) { |
10906 | ret = pmu_dev_alloc(pmu); | |
10907 | if (ret) | |
10908 | goto free_idr; | |
10909 | } | |
10910 | ||
2e80a82a | 10911 | skip_type: |
26657848 PZ |
10912 | if (pmu->task_ctx_nr == perf_hw_context) { |
10913 | static int hw_context_taken = 0; | |
10914 | ||
5101ef20 MR |
10915 | /* |
10916 | * Other than systems with heterogeneous CPUs, it never makes | |
10917 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10918 | * uncore must use perf_invalid_context. | |
10919 | */ | |
10920 | if (WARN_ON_ONCE(hw_context_taken && | |
10921 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10922 | pmu->task_ctx_nr = perf_invalid_context; |
10923 | ||
10924 | hw_context_taken = 1; | |
10925 | } | |
10926 | ||
8dc85d54 PZ |
10927 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10928 | if (pmu->pmu_cpu_context) | |
10929 | goto got_cpu_context; | |
f29ac756 | 10930 | |
c4814202 | 10931 | ret = -ENOMEM; |
108b02cf PZ |
10932 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10933 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10934 | goto free_dev; |
f344011c | 10935 | |
108b02cf PZ |
10936 | for_each_possible_cpu(cpu) { |
10937 | struct perf_cpu_context *cpuctx; | |
10938 | ||
10939 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10940 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10941 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10942 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10943 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10944 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10945 | |
272325c4 | 10946 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
10947 | |
10948 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
10949 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 10950 | } |
76e1d904 | 10951 | |
8dc85d54 | 10952 | got_cpu_context: |
ad5133b7 PZ |
10953 | if (!pmu->start_txn) { |
10954 | if (pmu->pmu_enable) { | |
10955 | /* | |
10956 | * If we have pmu_enable/pmu_disable calls, install | |
10957 | * transaction stubs that use that to try and batch | |
10958 | * hardware accesses. | |
10959 | */ | |
10960 | pmu->start_txn = perf_pmu_start_txn; | |
10961 | pmu->commit_txn = perf_pmu_commit_txn; | |
10962 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10963 | } else { | |
fbbe0701 | 10964 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10965 | pmu->commit_txn = perf_pmu_nop_int; |
10966 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10967 | } |
5c92d124 | 10968 | } |
15dbf27c | 10969 | |
ad5133b7 PZ |
10970 | if (!pmu->pmu_enable) { |
10971 | pmu->pmu_enable = perf_pmu_nop_void; | |
10972 | pmu->pmu_disable = perf_pmu_nop_void; | |
10973 | } | |
10974 | ||
81ec3f3c JO |
10975 | if (!pmu->check_period) |
10976 | pmu->check_period = perf_event_nop_int; | |
10977 | ||
35edc2a5 PZ |
10978 | if (!pmu->event_idx) |
10979 | pmu->event_idx = perf_event_idx_default; | |
10980 | ||
d44f821b LK |
10981 | /* |
10982 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10983 | * since these cannot be in the IDR. This way the linear search | |
10984 | * is fast, provided a valid software event is provided. | |
10985 | */ | |
10986 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10987 | list_add_rcu(&pmu->entry, &pmus); | |
10988 | else | |
10989 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10990 | ||
bed5b25a | 10991 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10992 | ret = 0; |
10993 | unlock: | |
b0a873eb PZ |
10994 | mutex_unlock(&pmus_lock); |
10995 | ||
33696fc0 | 10996 | return ret; |
108b02cf | 10997 | |
abe43400 PZ |
10998 | free_dev: |
10999 | device_del(pmu->dev); | |
11000 | put_device(pmu->dev); | |
11001 | ||
2e80a82a | 11002 | free_idr: |
66d258c5 | 11003 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
11004 | idr_remove(&pmu_idr, pmu->type); |
11005 | ||
108b02cf PZ |
11006 | free_pdc: |
11007 | free_percpu(pmu->pmu_disable_count); | |
11008 | goto unlock; | |
f29ac756 | 11009 | } |
c464c76e | 11010 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 11011 | |
b0a873eb | 11012 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 11013 | { |
b0a873eb PZ |
11014 | mutex_lock(&pmus_lock); |
11015 | list_del_rcu(&pmu->entry); | |
5c92d124 | 11016 | |
0475f9ea | 11017 | /* |
cde8e884 PZ |
11018 | * We dereference the pmu list under both SRCU and regular RCU, so |
11019 | * synchronize against both of those. | |
0475f9ea | 11020 | */ |
b0a873eb | 11021 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 11022 | synchronize_rcu(); |
d6d020e9 | 11023 | |
33696fc0 | 11024 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 11025 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 11026 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 11027 | if (pmu_bus_running) { |
0933840a JO |
11028 | if (pmu->nr_addr_filters) |
11029 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
11030 | device_del(pmu->dev); | |
11031 | put_device(pmu->dev); | |
11032 | } | |
51676957 | 11033 | free_pmu_context(pmu); |
a9f97721 | 11034 | mutex_unlock(&pmus_lock); |
b0a873eb | 11035 | } |
c464c76e | 11036 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 11037 | |
e321d02d KL |
11038 | static inline bool has_extended_regs(struct perf_event *event) |
11039 | { | |
11040 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
11041 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
11042 | } | |
11043 | ||
cc34b98b MR |
11044 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
11045 | { | |
ccd41c86 | 11046 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
11047 | int ret; |
11048 | ||
11049 | if (!try_module_get(pmu->module)) | |
11050 | return -ENODEV; | |
ccd41c86 | 11051 | |
0c7296ca PZ |
11052 | /* |
11053 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
11054 | * for example, validate if the group fits on the PMU. Therefore, | |
11055 | * if this is a sibling event, acquire the ctx->mutex to protect | |
11056 | * the sibling_list. | |
11057 | */ | |
11058 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
11059 | /* |
11060 | * This ctx->mutex can nest when we're called through | |
11061 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
11062 | */ | |
11063 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
11064 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
11065 | BUG_ON(!ctx); |
11066 | } | |
11067 | ||
cc34b98b MR |
11068 | event->pmu = pmu; |
11069 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
11070 | |
11071 | if (ctx) | |
11072 | perf_event_ctx_unlock(event->group_leader, ctx); | |
11073 | ||
cc6795ae | 11074 | if (!ret) { |
e321d02d KL |
11075 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
11076 | has_extended_regs(event)) | |
11077 | ret = -EOPNOTSUPP; | |
11078 | ||
cc6795ae | 11079 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 11080 | event_has_any_exclude_flag(event)) |
cc6795ae | 11081 | ret = -EINVAL; |
e321d02d KL |
11082 | |
11083 | if (ret && event->destroy) | |
11084 | event->destroy(event); | |
cc6795ae AM |
11085 | } |
11086 | ||
cc34b98b MR |
11087 | if (ret) |
11088 | module_put(pmu->module); | |
11089 | ||
11090 | return ret; | |
11091 | } | |
11092 | ||
18ab2cd3 | 11093 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 11094 | { |
66d258c5 | 11095 | int idx, type, ret; |
85c617ab | 11096 | struct pmu *pmu; |
b0a873eb PZ |
11097 | |
11098 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 11099 | |
40999312 KL |
11100 | /* Try parent's PMU first: */ |
11101 | if (event->parent && event->parent->pmu) { | |
11102 | pmu = event->parent->pmu; | |
11103 | ret = perf_try_init_event(pmu, event); | |
11104 | if (!ret) | |
11105 | goto unlock; | |
11106 | } | |
11107 | ||
66d258c5 PZ |
11108 | /* |
11109 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
11110 | * are often aliases for PERF_TYPE_RAW. | |
11111 | */ | |
11112 | type = event->attr.type; | |
11113 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
11114 | type = PERF_TYPE_RAW; | |
11115 | ||
11116 | again: | |
2e80a82a | 11117 | rcu_read_lock(); |
66d258c5 | 11118 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 11119 | rcu_read_unlock(); |
940c5b29 | 11120 | if (pmu) { |
cc34b98b | 11121 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
11122 | if (ret == -ENOENT && event->attr.type != type) { |
11123 | type = event->attr.type; | |
11124 | goto again; | |
11125 | } | |
11126 | ||
940c5b29 LM |
11127 | if (ret) |
11128 | pmu = ERR_PTR(ret); | |
66d258c5 | 11129 | |
2e80a82a | 11130 | goto unlock; |
940c5b29 | 11131 | } |
2e80a82a | 11132 | |
9f0bff11 | 11133 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 11134 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 11135 | if (!ret) |
e5f4d339 | 11136 | goto unlock; |
76e1d904 | 11137 | |
b0a873eb PZ |
11138 | if (ret != -ENOENT) { |
11139 | pmu = ERR_PTR(ret); | |
e5f4d339 | 11140 | goto unlock; |
f344011c | 11141 | } |
5c92d124 | 11142 | } |
e5f4d339 PZ |
11143 | pmu = ERR_PTR(-ENOENT); |
11144 | unlock: | |
b0a873eb | 11145 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 11146 | |
4aeb0b42 | 11147 | return pmu; |
5c92d124 IM |
11148 | } |
11149 | ||
f2fb6bef KL |
11150 | static void attach_sb_event(struct perf_event *event) |
11151 | { | |
11152 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
11153 | ||
11154 | raw_spin_lock(&pel->lock); | |
11155 | list_add_rcu(&event->sb_list, &pel->list); | |
11156 | raw_spin_unlock(&pel->lock); | |
11157 | } | |
11158 | ||
aab5b71e PZ |
11159 | /* |
11160 | * We keep a list of all !task (and therefore per-cpu) events | |
11161 | * that need to receive side-band records. | |
11162 | * | |
11163 | * This avoids having to scan all the various PMU per-cpu contexts | |
11164 | * looking for them. | |
11165 | */ | |
f2fb6bef KL |
11166 | static void account_pmu_sb_event(struct perf_event *event) |
11167 | { | |
a4f144eb | 11168 | if (is_sb_event(event)) |
f2fb6bef KL |
11169 | attach_sb_event(event); |
11170 | } | |
11171 | ||
4beb31f3 FW |
11172 | static void account_event_cpu(struct perf_event *event, int cpu) |
11173 | { | |
11174 | if (event->parent) | |
11175 | return; | |
11176 | ||
4beb31f3 FW |
11177 | if (is_cgroup_event(event)) |
11178 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
11179 | } | |
11180 | ||
555e0c1e FW |
11181 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
11182 | static void account_freq_event_nohz(void) | |
11183 | { | |
11184 | #ifdef CONFIG_NO_HZ_FULL | |
11185 | /* Lock so we don't race with concurrent unaccount */ | |
11186 | spin_lock(&nr_freq_lock); | |
11187 | if (atomic_inc_return(&nr_freq_events) == 1) | |
11188 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
11189 | spin_unlock(&nr_freq_lock); | |
11190 | #endif | |
11191 | } | |
11192 | ||
11193 | static void account_freq_event(void) | |
11194 | { | |
11195 | if (tick_nohz_full_enabled()) | |
11196 | account_freq_event_nohz(); | |
11197 | else | |
11198 | atomic_inc(&nr_freq_events); | |
11199 | } | |
11200 | ||
11201 | ||
766d6c07 FW |
11202 | static void account_event(struct perf_event *event) |
11203 | { | |
25432ae9 PZ |
11204 | bool inc = false; |
11205 | ||
4beb31f3 FW |
11206 | if (event->parent) |
11207 | return; | |
11208 | ||
f008790a | 11209 | if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB)) |
25432ae9 | 11210 | inc = true; |
766d6c07 FW |
11211 | if (event->attr.mmap || event->attr.mmap_data) |
11212 | atomic_inc(&nr_mmap_events); | |
11213 | if (event->attr.comm) | |
11214 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
11215 | if (event->attr.namespaces) |
11216 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
11217 | if (event->attr.cgroup) |
11218 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
11219 | if (event->attr.task) |
11220 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
11221 | if (event->attr.freq) |
11222 | account_freq_event(); | |
45ac1403 AH |
11223 | if (event->attr.context_switch) { |
11224 | atomic_inc(&nr_switch_events); | |
25432ae9 | 11225 | inc = true; |
45ac1403 | 11226 | } |
4beb31f3 | 11227 | if (has_branch_stack(event)) |
25432ae9 | 11228 | inc = true; |
4beb31f3 | 11229 | if (is_cgroup_event(event)) |
25432ae9 | 11230 | inc = true; |
76193a94 SL |
11231 | if (event->attr.ksymbol) |
11232 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
11233 | if (event->attr.bpf_event) |
11234 | atomic_inc(&nr_bpf_events); | |
e17d43b9 AH |
11235 | if (event->attr.text_poke) |
11236 | atomic_inc(&nr_text_poke_events); | |
25432ae9 | 11237 | |
9107c89e | 11238 | if (inc) { |
5bce9db1 AS |
11239 | /* |
11240 | * We need the mutex here because static_branch_enable() | |
11241 | * must complete *before* the perf_sched_count increment | |
11242 | * becomes visible. | |
11243 | */ | |
9107c89e PZ |
11244 | if (atomic_inc_not_zero(&perf_sched_count)) |
11245 | goto enabled; | |
11246 | ||
11247 | mutex_lock(&perf_sched_mutex); | |
11248 | if (!atomic_read(&perf_sched_count)) { | |
11249 | static_branch_enable(&perf_sched_events); | |
11250 | /* | |
11251 | * Guarantee that all CPUs observe they key change and | |
11252 | * call the perf scheduling hooks before proceeding to | |
11253 | * install events that need them. | |
11254 | */ | |
0809d954 | 11255 | synchronize_rcu(); |
9107c89e PZ |
11256 | } |
11257 | /* | |
11258 | * Now that we have waited for the sync_sched(), allow further | |
11259 | * increments to by-pass the mutex. | |
11260 | */ | |
11261 | atomic_inc(&perf_sched_count); | |
11262 | mutex_unlock(&perf_sched_mutex); | |
11263 | } | |
11264 | enabled: | |
4beb31f3 FW |
11265 | |
11266 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
11267 | |
11268 | account_pmu_sb_event(event); | |
766d6c07 FW |
11269 | } |
11270 | ||
0793a61d | 11271 | /* |
788faab7 | 11272 | * Allocate and initialize an event structure |
0793a61d | 11273 | */ |
cdd6c482 | 11274 | static struct perf_event * |
c3f00c70 | 11275 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
11276 | struct task_struct *task, |
11277 | struct perf_event *group_leader, | |
11278 | struct perf_event *parent_event, | |
4dc0da86 | 11279 | perf_overflow_handler_t overflow_handler, |
79dff51e | 11280 | void *context, int cgroup_fd) |
0793a61d | 11281 | { |
51b0fe39 | 11282 | struct pmu *pmu; |
cdd6c482 IM |
11283 | struct perf_event *event; |
11284 | struct hw_perf_event *hwc; | |
90983b16 | 11285 | long err = -EINVAL; |
0793a61d | 11286 | |
66832eb4 ON |
11287 | if ((unsigned)cpu >= nr_cpu_ids) { |
11288 | if (!task || cpu != -1) | |
11289 | return ERR_PTR(-EINVAL); | |
11290 | } | |
11291 | ||
c3f00c70 | 11292 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 11293 | if (!event) |
d5d2bc0d | 11294 | return ERR_PTR(-ENOMEM); |
0793a61d | 11295 | |
04289bb9 | 11296 | /* |
cdd6c482 | 11297 | * Single events are their own group leaders, with an |
04289bb9 IM |
11298 | * empty sibling list: |
11299 | */ | |
11300 | if (!group_leader) | |
cdd6c482 | 11301 | group_leader = event; |
04289bb9 | 11302 | |
cdd6c482 IM |
11303 | mutex_init(&event->child_mutex); |
11304 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 11305 | |
cdd6c482 IM |
11306 | INIT_LIST_HEAD(&event->event_entry); |
11307 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 11308 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 11309 | init_event_group(event); |
10c6db11 | 11310 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 11311 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 11312 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
11313 | INIT_HLIST_NODE(&event->hlist_entry); |
11314 | ||
10c6db11 | 11315 | |
cdd6c482 | 11316 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 11317 | event->pending_disable = -1; |
e360adbe | 11318 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 11319 | |
cdd6c482 | 11320 | mutex_init(&event->mmap_mutex); |
375637bc | 11321 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11322 | |
a6fa941d | 11323 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11324 | event->cpu = cpu; |
11325 | event->attr = *attr; | |
11326 | event->group_leader = group_leader; | |
11327 | event->pmu = NULL; | |
cdd6c482 | 11328 | event->oncpu = -1; |
a96bbc16 | 11329 | |
cdd6c482 | 11330 | event->parent = parent_event; |
b84fbc9f | 11331 | |
17cf22c3 | 11332 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11333 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11334 | |
cdd6c482 | 11335 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11336 | |
d580ff86 PZ |
11337 | if (task) { |
11338 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11339 | /* |
50f16a8b PZ |
11340 | * XXX pmu::event_init needs to know what task to account to |
11341 | * and we cannot use the ctx information because we need the | |
11342 | * pmu before we get a ctx. | |
d580ff86 | 11343 | */ |
7b3c92b8 | 11344 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11345 | } |
11346 | ||
34f43927 PZ |
11347 | event->clock = &local_clock; |
11348 | if (parent_event) | |
11349 | event->clock = parent_event->clock; | |
11350 | ||
4dc0da86 | 11351 | if (!overflow_handler && parent_event) { |
b326e956 | 11352 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11353 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11354 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11355 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11356 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11357 | |
85192dbf | 11358 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11359 | event->prog = prog; |
11360 | event->orig_overflow_handler = | |
11361 | parent_event->orig_overflow_handler; | |
11362 | } | |
11363 | #endif | |
4dc0da86 | 11364 | } |
66832eb4 | 11365 | |
1879445d WN |
11366 | if (overflow_handler) { |
11367 | event->overflow_handler = overflow_handler; | |
11368 | event->overflow_handler_context = context; | |
9ecda41a WN |
11369 | } else if (is_write_backward(event)){ |
11370 | event->overflow_handler = perf_event_output_backward; | |
11371 | event->overflow_handler_context = NULL; | |
1879445d | 11372 | } else { |
9ecda41a | 11373 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11374 | event->overflow_handler_context = NULL; |
11375 | } | |
97eaf530 | 11376 | |
0231bb53 | 11377 | perf_event__state_init(event); |
a86ed508 | 11378 | |
4aeb0b42 | 11379 | pmu = NULL; |
b8e83514 | 11380 | |
cdd6c482 | 11381 | hwc = &event->hw; |
bd2b5b12 | 11382 | hwc->sample_period = attr->sample_period; |
0d48696f | 11383 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11384 | hwc->sample_period = 1; |
eced1dfc | 11385 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11386 | |
e7850595 | 11387 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11388 | |
2023b359 | 11389 | /* |
ba5213ae PZ |
11390 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11391 | * See perf_output_read(). | |
2023b359 | 11392 | */ |
ba5213ae | 11393 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11394 | goto err_ns; |
a46a2300 YZ |
11395 | |
11396 | if (!has_branch_stack(event)) | |
11397 | event->attr.branch_sample_type = 0; | |
2023b359 | 11398 | |
b0a873eb | 11399 | pmu = perf_init_event(event); |
85c617ab | 11400 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11401 | err = PTR_ERR(pmu); |
90983b16 | 11402 | goto err_ns; |
621a01ea | 11403 | } |
d5d2bc0d | 11404 | |
09f4e8f0 PZ |
11405 | /* |
11406 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11407 | * be different on other CPUs in the uncore mask. | |
11408 | */ | |
11409 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11410 | err = -EINVAL; | |
11411 | goto err_pmu; | |
11412 | } | |
11413 | ||
ab43762e AS |
11414 | if (event->attr.aux_output && |
11415 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11416 | err = -EOPNOTSUPP; | |
11417 | goto err_pmu; | |
11418 | } | |
11419 | ||
98add2af PZ |
11420 | if (cgroup_fd != -1) { |
11421 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11422 | if (err) | |
11423 | goto err_pmu; | |
11424 | } | |
11425 | ||
bed5b25a AS |
11426 | err = exclusive_event_init(event); |
11427 | if (err) | |
11428 | goto err_pmu; | |
11429 | ||
375637bc | 11430 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11431 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11432 | sizeof(struct perf_addr_filter_range), | |
11433 | GFP_KERNEL); | |
11434 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11435 | err = -ENOMEM; |
375637bc | 11436 | goto err_per_task; |
36cc2b92 | 11437 | } |
375637bc | 11438 | |
18736eef AS |
11439 | /* |
11440 | * Clone the parent's vma offsets: they are valid until exec() | |
11441 | * even if the mm is not shared with the parent. | |
11442 | */ | |
11443 | if (event->parent) { | |
11444 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11445 | ||
11446 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11447 | memcpy(event->addr_filter_ranges, |
11448 | event->parent->addr_filter_ranges, | |
11449 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11450 | raw_spin_unlock_irq(&ifh->lock); |
11451 | } | |
11452 | ||
375637bc AS |
11453 | /* force hw sync on the address filters */ |
11454 | event->addr_filters_gen = 1; | |
11455 | } | |
11456 | ||
cdd6c482 | 11457 | if (!event->parent) { |
927c7a9e | 11458 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11459 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11460 | if (err) |
375637bc | 11461 | goto err_addr_filters; |
d010b332 | 11462 | } |
f344011c | 11463 | } |
9ee318a7 | 11464 | |
da97e184 JFG |
11465 | err = security_perf_event_alloc(event); |
11466 | if (err) | |
11467 | goto err_callchain_buffer; | |
11468 | ||
927a5570 AS |
11469 | /* symmetric to unaccount_event() in _free_event() */ |
11470 | account_event(event); | |
11471 | ||
cdd6c482 | 11472 | return event; |
90983b16 | 11473 | |
da97e184 JFG |
11474 | err_callchain_buffer: |
11475 | if (!event->parent) { | |
11476 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11477 | put_callchain_buffers(); | |
11478 | } | |
375637bc | 11479 | err_addr_filters: |
c60f83b8 | 11480 | kfree(event->addr_filter_ranges); |
375637bc | 11481 | |
bed5b25a AS |
11482 | err_per_task: |
11483 | exclusive_event_destroy(event); | |
11484 | ||
90983b16 | 11485 | err_pmu: |
98add2af PZ |
11486 | if (is_cgroup_event(event)) |
11487 | perf_detach_cgroup(event); | |
90983b16 FW |
11488 | if (event->destroy) |
11489 | event->destroy(event); | |
c464c76e | 11490 | module_put(pmu->module); |
90983b16 FW |
11491 | err_ns: |
11492 | if (event->ns) | |
11493 | put_pid_ns(event->ns); | |
621b6d2e PB |
11494 | if (event->hw.target) |
11495 | put_task_struct(event->hw.target); | |
90983b16 FW |
11496 | kfree(event); |
11497 | ||
11498 | return ERR_PTR(err); | |
0793a61d TG |
11499 | } |
11500 | ||
cdd6c482 IM |
11501 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11502 | struct perf_event_attr *attr) | |
974802ea | 11503 | { |
974802ea | 11504 | u32 size; |
cdf8073d | 11505 | int ret; |
974802ea | 11506 | |
c2ba8f41 | 11507 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11508 | memset(attr, 0, sizeof(*attr)); |
11509 | ||
11510 | ret = get_user(size, &uattr->size); | |
11511 | if (ret) | |
11512 | return ret; | |
11513 | ||
c2ba8f41 AS |
11514 | /* ABI compatibility quirk: */ |
11515 | if (!size) | |
974802ea | 11516 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11517 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11518 | goto err_size; |
11519 | ||
c2ba8f41 AS |
11520 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11521 | if (ret) { | |
11522 | if (ret == -E2BIG) | |
11523 | goto err_size; | |
11524 | return ret; | |
974802ea PZ |
11525 | } |
11526 | ||
f12f42ac MX |
11527 | attr->size = size; |
11528 | ||
a4faf00d | 11529 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11530 | return -EINVAL; |
11531 | ||
11532 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11533 | return -EINVAL; | |
11534 | ||
11535 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11536 | return -EINVAL; | |
11537 | ||
bce38cd5 SE |
11538 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11539 | u64 mask = attr->branch_sample_type; | |
11540 | ||
11541 | /* only using defined bits */ | |
11542 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11543 | return -EINVAL; | |
11544 | ||
11545 | /* at least one branch bit must be set */ | |
11546 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11547 | return -EINVAL; | |
11548 | ||
bce38cd5 SE |
11549 | /* propagate priv level, when not set for branch */ |
11550 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11551 | ||
11552 | /* exclude_kernel checked on syscall entry */ | |
11553 | if (!attr->exclude_kernel) | |
11554 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11555 | ||
11556 | if (!attr->exclude_user) | |
11557 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11558 | ||
11559 | if (!attr->exclude_hv) | |
11560 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11561 | /* | |
11562 | * adjust user setting (for HW filter setup) | |
11563 | */ | |
11564 | attr->branch_sample_type = mask; | |
11565 | } | |
e712209a | 11566 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11567 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11568 | ret = perf_allow_kernel(attr); | |
11569 | if (ret) | |
11570 | return ret; | |
11571 | } | |
bce38cd5 | 11572 | } |
4018994f | 11573 | |
c5ebcedb | 11574 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11575 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11576 | if (ret) |
11577 | return ret; | |
11578 | } | |
11579 | ||
11580 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11581 | if (!arch_perf_have_user_stack_dump()) | |
11582 | return -ENOSYS; | |
11583 | ||
11584 | /* | |
11585 | * We have __u32 type for the size, but so far | |
11586 | * we can only use __u16 as maximum due to the | |
11587 | * __u16 sample size limit. | |
11588 | */ | |
11589 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11590 | return -EINVAL; |
c5ebcedb | 11591 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11592 | return -EINVAL; |
c5ebcedb | 11593 | } |
4018994f | 11594 | |
5f970521 JO |
11595 | if (!attr->sample_max_stack) |
11596 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11597 | ||
60e2364e SE |
11598 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11599 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11600 | |
11601 | #ifndef CONFIG_CGROUP_PERF | |
11602 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11603 | return -EINVAL; | |
11604 | #endif | |
11605 | ||
974802ea PZ |
11606 | out: |
11607 | return ret; | |
11608 | ||
11609 | err_size: | |
11610 | put_user(sizeof(*attr), &uattr->size); | |
11611 | ret = -E2BIG; | |
11612 | goto out; | |
11613 | } | |
11614 | ||
ac9721f3 PZ |
11615 | static int |
11616 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11617 | { |
56de4e8f | 11618 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11619 | int ret = -EINVAL; |
11620 | ||
ac9721f3 | 11621 | if (!output_event) |
a4be7c27 PZ |
11622 | goto set; |
11623 | ||
ac9721f3 PZ |
11624 | /* don't allow circular references */ |
11625 | if (event == output_event) | |
a4be7c27 PZ |
11626 | goto out; |
11627 | ||
0f139300 PZ |
11628 | /* |
11629 | * Don't allow cross-cpu buffers | |
11630 | */ | |
11631 | if (output_event->cpu != event->cpu) | |
11632 | goto out; | |
11633 | ||
11634 | /* | |
76369139 | 11635 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11636 | */ |
11637 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11638 | goto out; | |
11639 | ||
34f43927 PZ |
11640 | /* |
11641 | * Mixing clocks in the same buffer is trouble you don't need. | |
11642 | */ | |
11643 | if (output_event->clock != event->clock) | |
11644 | goto out; | |
11645 | ||
9ecda41a WN |
11646 | /* |
11647 | * Either writing ring buffer from beginning or from end. | |
11648 | * Mixing is not allowed. | |
11649 | */ | |
11650 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11651 | goto out; | |
11652 | ||
45bfb2e5 PZ |
11653 | /* |
11654 | * If both events generate aux data, they must be on the same PMU | |
11655 | */ | |
11656 | if (has_aux(event) && has_aux(output_event) && | |
11657 | event->pmu != output_event->pmu) | |
11658 | goto out; | |
11659 | ||
a4be7c27 | 11660 | set: |
cdd6c482 | 11661 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11662 | /* Can't redirect output if we've got an active mmap() */ |
11663 | if (atomic_read(&event->mmap_count)) | |
11664 | goto unlock; | |
a4be7c27 | 11665 | |
ac9721f3 | 11666 | if (output_event) { |
76369139 FW |
11667 | /* get the rb we want to redirect to */ |
11668 | rb = ring_buffer_get(output_event); | |
11669 | if (!rb) | |
ac9721f3 | 11670 | goto unlock; |
a4be7c27 PZ |
11671 | } |
11672 | ||
b69cf536 | 11673 | ring_buffer_attach(event, rb); |
9bb5d40c | 11674 | |
a4be7c27 | 11675 | ret = 0; |
ac9721f3 PZ |
11676 | unlock: |
11677 | mutex_unlock(&event->mmap_mutex); | |
11678 | ||
a4be7c27 | 11679 | out: |
a4be7c27 PZ |
11680 | return ret; |
11681 | } | |
11682 | ||
f63a8daa PZ |
11683 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11684 | { | |
11685 | if (b < a) | |
11686 | swap(a, b); | |
11687 | ||
11688 | mutex_lock(a); | |
11689 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11690 | } | |
11691 | ||
34f43927 PZ |
11692 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11693 | { | |
11694 | bool nmi_safe = false; | |
11695 | ||
11696 | switch (clk_id) { | |
11697 | case CLOCK_MONOTONIC: | |
11698 | event->clock = &ktime_get_mono_fast_ns; | |
11699 | nmi_safe = true; | |
11700 | break; | |
11701 | ||
11702 | case CLOCK_MONOTONIC_RAW: | |
11703 | event->clock = &ktime_get_raw_fast_ns; | |
11704 | nmi_safe = true; | |
11705 | break; | |
11706 | ||
11707 | case CLOCK_REALTIME: | |
11708 | event->clock = &ktime_get_real_ns; | |
11709 | break; | |
11710 | ||
11711 | case CLOCK_BOOTTIME: | |
9285ec4c | 11712 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11713 | break; |
11714 | ||
11715 | case CLOCK_TAI: | |
9285ec4c | 11716 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11717 | break; |
11718 | ||
11719 | default: | |
11720 | return -EINVAL; | |
11721 | } | |
11722 | ||
11723 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11724 | return -EINVAL; | |
11725 | ||
11726 | return 0; | |
11727 | } | |
11728 | ||
321027c1 PZ |
11729 | /* |
11730 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11731 | * mutexes. | |
11732 | */ | |
11733 | static struct perf_event_context * | |
11734 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11735 | struct perf_event_context *ctx) | |
11736 | { | |
11737 | struct perf_event_context *gctx; | |
11738 | ||
11739 | again: | |
11740 | rcu_read_lock(); | |
11741 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11742 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11743 | rcu_read_unlock(); |
11744 | goto again; | |
11745 | } | |
11746 | rcu_read_unlock(); | |
11747 | ||
11748 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11749 | ||
11750 | if (group_leader->ctx != gctx) { | |
11751 | mutex_unlock(&ctx->mutex); | |
11752 | mutex_unlock(&gctx->mutex); | |
11753 | put_ctx(gctx); | |
11754 | goto again; | |
11755 | } | |
11756 | ||
11757 | return gctx; | |
11758 | } | |
11759 | ||
0793a61d | 11760 | /** |
cdd6c482 | 11761 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11762 | * |
cdd6c482 | 11763 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11764 | * @pid: target pid |
9f66a381 | 11765 | * @cpu: target cpu |
cdd6c482 | 11766 | * @group_fd: group leader event fd |
0793a61d | 11767 | */ |
cdd6c482 IM |
11768 | SYSCALL_DEFINE5(perf_event_open, |
11769 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11770 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11771 | { |
b04243ef PZ |
11772 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11773 | struct perf_event *event, *sibling; | |
cdd6c482 | 11774 | struct perf_event_attr attr; |
3f649ab7 | 11775 | struct perf_event_context *ctx, *gctx; |
cdd6c482 | 11776 | struct file *event_file = NULL; |
2903ff01 | 11777 | struct fd group = {NULL, 0}; |
38a81da2 | 11778 | struct task_struct *task = NULL; |
89a1e187 | 11779 | struct pmu *pmu; |
ea635c64 | 11780 | int event_fd; |
b04243ef | 11781 | int move_group = 0; |
dc86cabe | 11782 | int err; |
a21b0b35 | 11783 | int f_flags = O_RDWR; |
79dff51e | 11784 | int cgroup_fd = -1; |
0793a61d | 11785 | |
2743a5b0 | 11786 | /* for future expandability... */ |
e5d1367f | 11787 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11788 | return -EINVAL; |
11789 | ||
da97e184 JFG |
11790 | /* Do we allow access to perf_event_open(2) ? */ |
11791 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11792 | if (err) | |
11793 | return err; | |
11794 | ||
04d76d75 BH |
11795 | if (perf_paranoid_any() && !capable(CAP_SYS_ADMIN)) |
11796 | return -EACCES; | |
11797 | ||
dc86cabe IM |
11798 | err = perf_copy_attr(attr_uptr, &attr); |
11799 | if (err) | |
11800 | return err; | |
eab656ae | 11801 | |
0764771d | 11802 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11803 | err = perf_allow_kernel(&attr); |
11804 | if (err) | |
11805 | return err; | |
0764771d PZ |
11806 | } |
11807 | ||
e4222673 | 11808 | if (attr.namespaces) { |
18aa1856 | 11809 | if (!perfmon_capable()) |
e4222673 HB |
11810 | return -EACCES; |
11811 | } | |
11812 | ||
df58ab24 | 11813 | if (attr.freq) { |
cdd6c482 | 11814 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11815 | return -EINVAL; |
0819b2e3 PZ |
11816 | } else { |
11817 | if (attr.sample_period & (1ULL << 63)) | |
11818 | return -EINVAL; | |
df58ab24 PZ |
11819 | } |
11820 | ||
fc7ce9c7 | 11821 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11822 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11823 | err = perf_allow_kernel(&attr); | |
11824 | if (err) | |
11825 | return err; | |
11826 | } | |
fc7ce9c7 | 11827 | |
b0c8fdc7 DH |
11828 | err = security_locked_down(LOCKDOWN_PERF); |
11829 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11830 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11831 | return err; | |
11832 | ||
11833 | err = 0; | |
11834 | ||
e5d1367f SE |
11835 | /* |
11836 | * In cgroup mode, the pid argument is used to pass the fd | |
11837 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11838 | * designates the cpu on which to monitor threads from that | |
11839 | * cgroup. | |
11840 | */ | |
11841 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11842 | return -EINVAL; | |
11843 | ||
a21b0b35 YD |
11844 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11845 | f_flags |= O_CLOEXEC; | |
11846 | ||
11847 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11848 | if (event_fd < 0) |
11849 | return event_fd; | |
11850 | ||
ac9721f3 | 11851 | if (group_fd != -1) { |
2903ff01 AV |
11852 | err = perf_fget_light(group_fd, &group); |
11853 | if (err) | |
d14b12d7 | 11854 | goto err_fd; |
2903ff01 | 11855 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11856 | if (flags & PERF_FLAG_FD_OUTPUT) |
11857 | output_event = group_leader; | |
11858 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11859 | group_leader = NULL; | |
11860 | } | |
11861 | ||
e5d1367f | 11862 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11863 | task = find_lively_task_by_vpid(pid); |
11864 | if (IS_ERR(task)) { | |
11865 | err = PTR_ERR(task); | |
11866 | goto err_group_fd; | |
11867 | } | |
11868 | } | |
11869 | ||
1f4ee503 PZ |
11870 | if (task && group_leader && |
11871 | group_leader->attr.inherit != attr.inherit) { | |
11872 | err = -EINVAL; | |
11873 | goto err_task; | |
11874 | } | |
11875 | ||
79dff51e MF |
11876 | if (flags & PERF_FLAG_PID_CGROUP) |
11877 | cgroup_fd = pid; | |
11878 | ||
4dc0da86 | 11879 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11880 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11881 | if (IS_ERR(event)) { |
11882 | err = PTR_ERR(event); | |
78af4dc9 | 11883 | goto err_task; |
d14b12d7 SE |
11884 | } |
11885 | ||
53b25335 VW |
11886 | if (is_sampling_event(event)) { |
11887 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11888 | err = -EOPNOTSUPP; |
53b25335 VW |
11889 | goto err_alloc; |
11890 | } | |
11891 | } | |
11892 | ||
89a1e187 PZ |
11893 | /* |
11894 | * Special case software events and allow them to be part of | |
11895 | * any hardware group. | |
11896 | */ | |
11897 | pmu = event->pmu; | |
b04243ef | 11898 | |
34f43927 PZ |
11899 | if (attr.use_clockid) { |
11900 | err = perf_event_set_clock(event, attr.clockid); | |
11901 | if (err) | |
11902 | goto err_alloc; | |
11903 | } | |
11904 | ||
4ff6a8de DCC |
11905 | if (pmu->task_ctx_nr == perf_sw_context) |
11906 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11907 | ||
a1150c20 SL |
11908 | if (group_leader) { |
11909 | if (is_software_event(event) && | |
11910 | !in_software_context(group_leader)) { | |
b04243ef | 11911 | /* |
a1150c20 SL |
11912 | * If the event is a sw event, but the group_leader |
11913 | * is on hw context. | |
b04243ef | 11914 | * |
a1150c20 SL |
11915 | * Allow the addition of software events to hw |
11916 | * groups, this is safe because software events | |
11917 | * never fail to schedule. | |
b04243ef | 11918 | */ |
a1150c20 SL |
11919 | pmu = group_leader->ctx->pmu; |
11920 | } else if (!is_software_event(event) && | |
11921 | is_software_event(group_leader) && | |
4ff6a8de | 11922 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11923 | /* |
11924 | * In case the group is a pure software group, and we | |
11925 | * try to add a hardware event, move the whole group to | |
11926 | * the hardware context. | |
11927 | */ | |
11928 | move_group = 1; | |
11929 | } | |
11930 | } | |
89a1e187 PZ |
11931 | |
11932 | /* | |
11933 | * Get the target context (task or percpu): | |
11934 | */ | |
4af57ef2 | 11935 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11936 | if (IS_ERR(ctx)) { |
11937 | err = PTR_ERR(ctx); | |
c6be5a5c | 11938 | goto err_alloc; |
89a1e187 PZ |
11939 | } |
11940 | ||
ccff286d | 11941 | /* |
cdd6c482 | 11942 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11943 | */ |
ac9721f3 | 11944 | if (group_leader) { |
dc86cabe | 11945 | err = -EINVAL; |
04289bb9 | 11946 | |
04289bb9 | 11947 | /* |
ccff286d IM |
11948 | * Do not allow a recursive hierarchy (this new sibling |
11949 | * becoming part of another group-sibling): | |
11950 | */ | |
11951 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11952 | goto err_context; |
34f43927 PZ |
11953 | |
11954 | /* All events in a group should have the same clock */ | |
11955 | if (group_leader->clock != event->clock) | |
11956 | goto err_context; | |
11957 | ||
ccff286d | 11958 | /* |
64aee2a9 MR |
11959 | * Make sure we're both events for the same CPU; |
11960 | * grouping events for different CPUs is broken; since | |
11961 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11962 | */ |
64aee2a9 MR |
11963 | if (group_leader->cpu != event->cpu) |
11964 | goto err_context; | |
c3c87e77 | 11965 | |
64aee2a9 MR |
11966 | /* |
11967 | * Make sure we're both on the same task, or both | |
11968 | * per-CPU events. | |
11969 | */ | |
11970 | if (group_leader->ctx->task != ctx->task) | |
11971 | goto err_context; | |
11972 | ||
11973 | /* | |
11974 | * Do not allow to attach to a group in a different task | |
11975 | * or CPU context. If we're moving SW events, we'll fix | |
11976 | * this up later, so allow that. | |
11977 | */ | |
11978 | if (!move_group && group_leader->ctx != ctx) | |
11979 | goto err_context; | |
b04243ef | 11980 | |
3b6f9e5c PM |
11981 | /* |
11982 | * Only a group leader can be exclusive or pinned | |
11983 | */ | |
0d48696f | 11984 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11985 | goto err_context; |
ac9721f3 PZ |
11986 | } |
11987 | ||
11988 | if (output_event) { | |
11989 | err = perf_event_set_output(event, output_event); | |
11990 | if (err) | |
c3f00c70 | 11991 | goto err_context; |
ac9721f3 | 11992 | } |
0793a61d | 11993 | |
a21b0b35 YD |
11994 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11995 | f_flags); | |
ea635c64 AV |
11996 | if (IS_ERR(event_file)) { |
11997 | err = PTR_ERR(event_file); | |
201c2f85 | 11998 | event_file = NULL; |
c3f00c70 | 11999 | goto err_context; |
ea635c64 | 12000 | } |
9b51f66d | 12001 | |
78af4dc9 | 12002 | if (task) { |
d01e7f10 | 12003 | err = down_read_interruptible(&task->signal->exec_update_lock); |
78af4dc9 | 12004 | if (err) |
12005 | goto err_file; | |
12006 | ||
12007 | /* | |
12008 | * Preserve ptrace permission check for backwards compatibility. | |
12009 | * | |
d01e7f10 | 12010 | * We must hold exec_update_lock across this and any potential |
78af4dc9 | 12011 | * perf_install_in_context() call for this new event to |
12012 | * serialize against exec() altering our credentials (and the | |
12013 | * perf_event_exit_task() that could imply). | |
12014 | */ | |
12015 | err = -EACCES; | |
12016 | if (!perfmon_capable() && !ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
12017 | goto err_cred; | |
12018 | } | |
12019 | ||
b04243ef | 12020 | if (move_group) { |
321027c1 PZ |
12021 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
12022 | ||
84c4e620 PZ |
12023 | if (gctx->task == TASK_TOMBSTONE) { |
12024 | err = -ESRCH; | |
12025 | goto err_locked; | |
12026 | } | |
321027c1 PZ |
12027 | |
12028 | /* | |
12029 | * Check if we raced against another sys_perf_event_open() call | |
12030 | * moving the software group underneath us. | |
12031 | */ | |
12032 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
12033 | /* | |
12034 | * If someone moved the group out from under us, check | |
12035 | * if this new event wound up on the same ctx, if so | |
12036 | * its the regular !move_group case, otherwise fail. | |
12037 | */ | |
12038 | if (gctx != ctx) { | |
12039 | err = -EINVAL; | |
12040 | goto err_locked; | |
12041 | } else { | |
12042 | perf_event_ctx_unlock(group_leader, gctx); | |
12043 | move_group = 0; | |
12044 | } | |
12045 | } | |
8a58ddae AS |
12046 | |
12047 | /* | |
12048 | * Failure to create exclusive events returns -EBUSY. | |
12049 | */ | |
12050 | err = -EBUSY; | |
12051 | if (!exclusive_event_installable(group_leader, ctx)) | |
12052 | goto err_locked; | |
12053 | ||
12054 | for_each_sibling_event(sibling, group_leader) { | |
12055 | if (!exclusive_event_installable(sibling, ctx)) | |
12056 | goto err_locked; | |
12057 | } | |
f55fc2a5 PZ |
12058 | } else { |
12059 | mutex_lock(&ctx->mutex); | |
12060 | } | |
12061 | ||
84c4e620 PZ |
12062 | if (ctx->task == TASK_TOMBSTONE) { |
12063 | err = -ESRCH; | |
12064 | goto err_locked; | |
12065 | } | |
12066 | ||
a723968c PZ |
12067 | if (!perf_event_validate_size(event)) { |
12068 | err = -E2BIG; | |
12069 | goto err_locked; | |
12070 | } | |
12071 | ||
a63fbed7 TG |
12072 | if (!task) { |
12073 | /* | |
12074 | * Check if the @cpu we're creating an event for is online. | |
12075 | * | |
12076 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12077 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12078 | */ | |
12079 | struct perf_cpu_context *cpuctx = | |
12080 | container_of(ctx, struct perf_cpu_context, ctx); | |
12081 | ||
12082 | if (!cpuctx->online) { | |
12083 | err = -ENODEV; | |
12084 | goto err_locked; | |
12085 | } | |
12086 | } | |
12087 | ||
da9ec3d3 MR |
12088 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
12089 | err = -EINVAL; | |
ab43762e | 12090 | goto err_locked; |
da9ec3d3 | 12091 | } |
a63fbed7 | 12092 | |
f55fc2a5 PZ |
12093 | /* |
12094 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
12095 | * because we need to serialize with concurrent event creation. | |
12096 | */ | |
12097 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
12098 | err = -EBUSY; |
12099 | goto err_locked; | |
12100 | } | |
f63a8daa | 12101 | |
f55fc2a5 PZ |
12102 | WARN_ON_ONCE(ctx->parent_ctx); |
12103 | ||
79c9ce57 PZ |
12104 | /* |
12105 | * This is the point on no return; we cannot fail hereafter. This is | |
12106 | * where we start modifying current state. | |
12107 | */ | |
12108 | ||
f55fc2a5 | 12109 | if (move_group) { |
f63a8daa PZ |
12110 | /* |
12111 | * See perf_event_ctx_lock() for comments on the details | |
12112 | * of swizzling perf_event::ctx. | |
12113 | */ | |
45a0e07a | 12114 | perf_remove_from_context(group_leader, 0); |
279b5165 | 12115 | put_ctx(gctx); |
0231bb53 | 12116 | |
edb39592 | 12117 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 12118 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
12119 | put_ctx(gctx); |
12120 | } | |
b04243ef | 12121 | |
f63a8daa PZ |
12122 | /* |
12123 | * Wait for everybody to stop referencing the events through | |
12124 | * the old lists, before installing it on new lists. | |
12125 | */ | |
0cda4c02 | 12126 | synchronize_rcu(); |
f63a8daa | 12127 | |
8f95b435 PZI |
12128 | /* |
12129 | * Install the group siblings before the group leader. | |
12130 | * | |
12131 | * Because a group leader will try and install the entire group | |
12132 | * (through the sibling list, which is still in-tact), we can | |
12133 | * end up with siblings installed in the wrong context. | |
12134 | * | |
12135 | * By installing siblings first we NO-OP because they're not | |
12136 | * reachable through the group lists. | |
12137 | */ | |
edb39592 | 12138 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 12139 | perf_event__state_init(sibling); |
9fc81d87 | 12140 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
12141 | get_ctx(ctx); |
12142 | } | |
8f95b435 PZI |
12143 | |
12144 | /* | |
12145 | * Removing from the context ends up with disabled | |
12146 | * event. What we want here is event in the initial | |
12147 | * startup state, ready to be add into new context. | |
12148 | */ | |
12149 | perf_event__state_init(group_leader); | |
12150 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
12151 | get_ctx(ctx); | |
bed5b25a AS |
12152 | } |
12153 | ||
f73e22ab PZ |
12154 | /* |
12155 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
12156 | * that we're serialized against further additions and before | |
12157 | * perf_install_in_context() which is the point the event is active and | |
12158 | * can use these values. | |
12159 | */ | |
12160 | perf_event__header_size(event); | |
12161 | perf_event__id_header_size(event); | |
12162 | ||
78cd2c74 PZ |
12163 | event->owner = current; |
12164 | ||
e2d37cd2 | 12165 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12166 | perf_unpin_context(ctx); |
f63a8daa | 12167 | |
f55fc2a5 | 12168 | if (move_group) |
321027c1 | 12169 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 12170 | mutex_unlock(&ctx->mutex); |
9b51f66d | 12171 | |
79c9ce57 | 12172 | if (task) { |
f7cfd871 | 12173 | up_read(&task->signal->exec_update_lock); |
79c9ce57 PZ |
12174 | put_task_struct(task); |
12175 | } | |
12176 | ||
cdd6c482 IM |
12177 | mutex_lock(¤t->perf_event_mutex); |
12178 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
12179 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 12180 | |
8a49542c PZ |
12181 | /* |
12182 | * Drop the reference on the group_event after placing the | |
12183 | * new event on the sibling_list. This ensures destruction | |
12184 | * of the group leader will find the pointer to itself in | |
12185 | * perf_group_detach(). | |
12186 | */ | |
2903ff01 | 12187 | fdput(group); |
ea635c64 AV |
12188 | fd_install(event_fd, event_file); |
12189 | return event_fd; | |
0793a61d | 12190 | |
f55fc2a5 PZ |
12191 | err_locked: |
12192 | if (move_group) | |
321027c1 | 12193 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 | 12194 | mutex_unlock(&ctx->mutex); |
78af4dc9 | 12195 | err_cred: |
12196 | if (task) | |
d01e7f10 | 12197 | up_read(&task->signal->exec_update_lock); |
78af4dc9 | 12198 | err_file: |
f55fc2a5 | 12199 | fput(event_file); |
c3f00c70 | 12200 | err_context: |
fe4b04fa | 12201 | perf_unpin_context(ctx); |
ea635c64 | 12202 | put_ctx(ctx); |
c6be5a5c | 12203 | err_alloc: |
13005627 PZ |
12204 | /* |
12205 | * If event_file is set, the fput() above will have called ->release() | |
12206 | * and that will take care of freeing the event. | |
12207 | */ | |
12208 | if (!event_file) | |
12209 | free_event(event); | |
1f4ee503 | 12210 | err_task: |
e7d0bc04 PZ |
12211 | if (task) |
12212 | put_task_struct(task); | |
89a1e187 | 12213 | err_group_fd: |
2903ff01 | 12214 | fdput(group); |
ea635c64 AV |
12215 | err_fd: |
12216 | put_unused_fd(event_fd); | |
dc86cabe | 12217 | return err; |
0793a61d TG |
12218 | } |
12219 | ||
fb0459d7 AV |
12220 | /** |
12221 | * perf_event_create_kernel_counter | |
12222 | * | |
12223 | * @attr: attributes of the counter to create | |
12224 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 12225 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
12226 | */ |
12227 | struct perf_event * | |
12228 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 12229 | struct task_struct *task, |
4dc0da86 AK |
12230 | perf_overflow_handler_t overflow_handler, |
12231 | void *context) | |
fb0459d7 | 12232 | { |
fb0459d7 | 12233 | struct perf_event_context *ctx; |
c3f00c70 | 12234 | struct perf_event *event; |
fb0459d7 | 12235 | int err; |
d859e29f | 12236 | |
dce5affb AS |
12237 | /* |
12238 | * Grouping is not supported for kernel events, neither is 'AUX', | |
12239 | * make sure the caller's intentions are adjusted. | |
12240 | */ | |
12241 | if (attr->aux_output) | |
12242 | return ERR_PTR(-EINVAL); | |
12243 | ||
4dc0da86 | 12244 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 12245 | overflow_handler, context, -1); |
c3f00c70 PZ |
12246 | if (IS_ERR(event)) { |
12247 | err = PTR_ERR(event); | |
12248 | goto err; | |
12249 | } | |
d859e29f | 12250 | |
f8697762 | 12251 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 12252 | event->owner = TASK_TOMBSTONE; |
f8697762 | 12253 | |
f25d8ba9 AS |
12254 | /* |
12255 | * Get the target context (task or percpu): | |
12256 | */ | |
4af57ef2 | 12257 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
12258 | if (IS_ERR(ctx)) { |
12259 | err = PTR_ERR(ctx); | |
c3f00c70 | 12260 | goto err_free; |
d859e29f | 12261 | } |
fb0459d7 | 12262 | |
fb0459d7 AV |
12263 | WARN_ON_ONCE(ctx->parent_ctx); |
12264 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
12265 | if (ctx->task == TASK_TOMBSTONE) { |
12266 | err = -ESRCH; | |
12267 | goto err_unlock; | |
12268 | } | |
12269 | ||
a63fbed7 TG |
12270 | if (!task) { |
12271 | /* | |
12272 | * Check if the @cpu we're creating an event for is online. | |
12273 | * | |
12274 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12275 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12276 | */ | |
12277 | struct perf_cpu_context *cpuctx = | |
12278 | container_of(ctx, struct perf_cpu_context, ctx); | |
12279 | if (!cpuctx->online) { | |
12280 | err = -ENODEV; | |
12281 | goto err_unlock; | |
12282 | } | |
12283 | } | |
12284 | ||
bed5b25a | 12285 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 12286 | err = -EBUSY; |
84c4e620 | 12287 | goto err_unlock; |
bed5b25a AS |
12288 | } |
12289 | ||
4ce54af8 | 12290 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12291 | perf_unpin_context(ctx); |
fb0459d7 AV |
12292 | mutex_unlock(&ctx->mutex); |
12293 | ||
fb0459d7 AV |
12294 | return event; |
12295 | ||
84c4e620 PZ |
12296 | err_unlock: |
12297 | mutex_unlock(&ctx->mutex); | |
12298 | perf_unpin_context(ctx); | |
12299 | put_ctx(ctx); | |
c3f00c70 PZ |
12300 | err_free: |
12301 | free_event(event); | |
12302 | err: | |
c6567f64 | 12303 | return ERR_PTR(err); |
9b51f66d | 12304 | } |
fb0459d7 | 12305 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 12306 | |
0cda4c02 YZ |
12307 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
12308 | { | |
12309 | struct perf_event_context *src_ctx; | |
12310 | struct perf_event_context *dst_ctx; | |
12311 | struct perf_event *event, *tmp; | |
12312 | LIST_HEAD(events); | |
12313 | ||
12314 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
12315 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
12316 | ||
f63a8daa PZ |
12317 | /* |
12318 | * See perf_event_ctx_lock() for comments on the details | |
12319 | * of swizzling perf_event::ctx. | |
12320 | */ | |
12321 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
12322 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12323 | event_entry) { | |
45a0e07a | 12324 | perf_remove_from_context(event, 0); |
9a545de0 | 12325 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12326 | put_ctx(src_ctx); |
9886167d | 12327 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12328 | } |
0cda4c02 | 12329 | |
8f95b435 PZI |
12330 | /* |
12331 | * Wait for the events to quiesce before re-instating them. | |
12332 | */ | |
0cda4c02 YZ |
12333 | synchronize_rcu(); |
12334 | ||
8f95b435 PZI |
12335 | /* |
12336 | * Re-instate events in 2 passes. | |
12337 | * | |
12338 | * Skip over group leaders and only install siblings on this first | |
12339 | * pass, siblings will not get enabled without a leader, however a | |
12340 | * leader will enable its siblings, even if those are still on the old | |
12341 | * context. | |
12342 | */ | |
12343 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12344 | if (event->group_leader == event) | |
12345 | continue; | |
12346 | ||
12347 | list_del(&event->migrate_entry); | |
12348 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12349 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12350 | account_event_cpu(event, dst_cpu); | |
12351 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12352 | get_ctx(dst_ctx); | |
12353 | } | |
12354 | ||
12355 | /* | |
12356 | * Once all the siblings are setup properly, install the group leaders | |
12357 | * to make it go. | |
12358 | */ | |
9886167d PZ |
12359 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12360 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12361 | if (event->state >= PERF_EVENT_STATE_OFF) |
12362 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12363 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12364 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12365 | get_ctx(dst_ctx); | |
12366 | } | |
12367 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12368 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12369 | } |
12370 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12371 | ||
cdd6c482 | 12372 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 12373 | struct task_struct *child) |
d859e29f | 12374 | { |
cdd6c482 | 12375 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12376 | u64 child_val; |
d859e29f | 12377 | |
cdd6c482 IM |
12378 | if (child_event->attr.inherit_stat) |
12379 | perf_event_read_event(child_event, child); | |
38b200d6 | 12380 | |
b5e58793 | 12381 | child_val = perf_event_count(child_event); |
d859e29f PM |
12382 | |
12383 | /* | |
12384 | * Add back the child's count to the parent's count: | |
12385 | */ | |
a6e6dea6 | 12386 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12387 | atomic64_add(child_event->total_time_enabled, |
12388 | &parent_event->child_total_time_enabled); | |
12389 | atomic64_add(child_event->total_time_running, | |
12390 | &parent_event->child_total_time_running); | |
d859e29f PM |
12391 | } |
12392 | ||
9b51f66d | 12393 | static void |
8ba289b8 PZ |
12394 | perf_event_exit_event(struct perf_event *child_event, |
12395 | struct perf_event_context *child_ctx, | |
12396 | struct task_struct *child) | |
9b51f66d | 12397 | { |
8ba289b8 PZ |
12398 | struct perf_event *parent_event = child_event->parent; |
12399 | ||
1903d50c PZ |
12400 | /* |
12401 | * Do not destroy the 'original' grouping; because of the context | |
12402 | * switch optimization the original events could've ended up in a | |
12403 | * random child task. | |
12404 | * | |
12405 | * If we were to destroy the original group, all group related | |
12406 | * operations would cease to function properly after this random | |
12407 | * child dies. | |
12408 | * | |
12409 | * Do destroy all inherited groups, we don't care about those | |
12410 | * and being thorough is better. | |
12411 | */ | |
32132a3d PZ |
12412 | raw_spin_lock_irq(&child_ctx->lock); |
12413 | WARN_ON_ONCE(child_ctx->is_active); | |
12414 | ||
8ba289b8 | 12415 | if (parent_event) |
32132a3d PZ |
12416 | perf_group_detach(child_event); |
12417 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 12418 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 12419 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 12420 | |
9b51f66d | 12421 | /* |
8ba289b8 | 12422 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 12423 | */ |
8ba289b8 | 12424 | if (!parent_event) { |
179033b3 | 12425 | perf_event_wakeup(child_event); |
8ba289b8 | 12426 | return; |
4bcf349a | 12427 | } |
8ba289b8 PZ |
12428 | /* |
12429 | * Child events can be cleaned up. | |
12430 | */ | |
12431 | ||
12432 | sync_child_event(child_event, child); | |
12433 | ||
12434 | /* | |
12435 | * Remove this event from the parent's list | |
12436 | */ | |
12437 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
12438 | mutex_lock(&parent_event->child_mutex); | |
12439 | list_del_init(&child_event->child_list); | |
12440 | mutex_unlock(&parent_event->child_mutex); | |
12441 | ||
12442 | /* | |
12443 | * Kick perf_poll() for is_event_hup(). | |
12444 | */ | |
12445 | perf_event_wakeup(parent_event); | |
12446 | free_event(child_event); | |
12447 | put_event(parent_event); | |
9b51f66d IM |
12448 | } |
12449 | ||
8dc85d54 | 12450 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12451 | { |
211de6eb | 12452 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12453 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12454 | |
12455 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12456 | |
6a3351b6 | 12457 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12458 | if (!child_ctx) |
9b51f66d IM |
12459 | return; |
12460 | ||
ad3a37de | 12461 | /* |
6a3351b6 PZ |
12462 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12463 | * ctx::mutex over the entire thing. This serializes against almost | |
12464 | * everything that wants to access the ctx. | |
12465 | * | |
12466 | * The exception is sys_perf_event_open() / | |
12467 | * perf_event_create_kernel_count() which does find_get_context() | |
12468 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12469 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12470 | */ |
6a3351b6 | 12471 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12472 | |
12473 | /* | |
6a3351b6 PZ |
12474 | * In a single ctx::lock section, de-schedule the events and detach the |
12475 | * context from the task such that we cannot ever get it scheduled back | |
12476 | * in. | |
c93f7669 | 12477 | */ |
6a3351b6 | 12478 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12479 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12480 | |
71a851b4 | 12481 | /* |
63b6da39 PZ |
12482 | * Now that the context is inactive, destroy the task <-> ctx relation |
12483 | * and mark the context dead. | |
71a851b4 | 12484 | */ |
63b6da39 PZ |
12485 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12486 | put_ctx(child_ctx); /* cannot be last */ | |
12487 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12488 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12489 | |
211de6eb | 12490 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12491 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12492 | |
211de6eb PZ |
12493 | if (clone_ctx) |
12494 | put_ctx(clone_ctx); | |
4a1c0f26 | 12495 | |
9f498cc5 | 12496 | /* |
cdd6c482 IM |
12497 | * Report the task dead after unscheduling the events so that we |
12498 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12499 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12500 | */ |
cdd6c482 | 12501 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12502 | |
ebf905fc | 12503 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 12504 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 12505 | |
a63eaf34 PM |
12506 | mutex_unlock(&child_ctx->mutex); |
12507 | ||
12508 | put_ctx(child_ctx); | |
9b51f66d IM |
12509 | } |
12510 | ||
8dc85d54 PZ |
12511 | /* |
12512 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12513 | * |
f7cfd871 | 12514 | * Can be called with exec_update_lock held when called from |
96ecee29 | 12515 | * setup_new_exec(). |
8dc85d54 PZ |
12516 | */ |
12517 | void perf_event_exit_task(struct task_struct *child) | |
12518 | { | |
8882135b | 12519 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12520 | int ctxn; |
12521 | ||
8882135b PZ |
12522 | mutex_lock(&child->perf_event_mutex); |
12523 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12524 | owner_entry) { | |
12525 | list_del_init(&event->owner_entry); | |
12526 | ||
12527 | /* | |
12528 | * Ensure the list deletion is visible before we clear | |
12529 | * the owner, closes a race against perf_release() where | |
12530 | * we need to serialize on the owner->perf_event_mutex. | |
12531 | */ | |
f47c02c0 | 12532 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12533 | } |
12534 | mutex_unlock(&child->perf_event_mutex); | |
12535 | ||
8dc85d54 PZ |
12536 | for_each_task_context_nr(ctxn) |
12537 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12538 | |
12539 | /* | |
12540 | * The perf_event_exit_task_context calls perf_event_task | |
12541 | * with child's task_ctx, which generates EXIT events for | |
12542 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12543 | * At this point we need to send EXIT events to cpu contexts. | |
12544 | */ | |
12545 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12546 | } |
12547 | ||
889ff015 FW |
12548 | static void perf_free_event(struct perf_event *event, |
12549 | struct perf_event_context *ctx) | |
12550 | { | |
12551 | struct perf_event *parent = event->parent; | |
12552 | ||
12553 | if (WARN_ON_ONCE(!parent)) | |
12554 | return; | |
12555 | ||
12556 | mutex_lock(&parent->child_mutex); | |
12557 | list_del_init(&event->child_list); | |
12558 | mutex_unlock(&parent->child_mutex); | |
12559 | ||
a6fa941d | 12560 | put_event(parent); |
889ff015 | 12561 | |
652884fe | 12562 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12563 | perf_group_detach(event); |
889ff015 | 12564 | list_del_event(event, ctx); |
652884fe | 12565 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12566 | free_event(event); |
12567 | } | |
12568 | ||
bbbee908 | 12569 | /* |
1cf8dfe8 PZ |
12570 | * Free a context as created by inheritance by perf_event_init_task() below, |
12571 | * used by fork() in case of fail. | |
652884fe | 12572 | * |
1cf8dfe8 PZ |
12573 | * Even though the task has never lived, the context and events have been |
12574 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12575 | */ |
cdd6c482 | 12576 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12577 | { |
8dc85d54 | 12578 | struct perf_event_context *ctx; |
cdd6c482 | 12579 | struct perf_event *event, *tmp; |
8dc85d54 | 12580 | int ctxn; |
bbbee908 | 12581 | |
8dc85d54 PZ |
12582 | for_each_task_context_nr(ctxn) { |
12583 | ctx = task->perf_event_ctxp[ctxn]; | |
12584 | if (!ctx) | |
12585 | continue; | |
bbbee908 | 12586 | |
8dc85d54 | 12587 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12588 | raw_spin_lock_irq(&ctx->lock); |
12589 | /* | |
12590 | * Destroy the task <-> ctx relation and mark the context dead. | |
12591 | * | |
12592 | * This is important because even though the task hasn't been | |
12593 | * exposed yet the context has been (through child_list). | |
12594 | */ | |
12595 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12596 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12597 | put_task_struct(task); /* cannot be last */ | |
12598 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12599 | |
15121c78 | 12600 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12601 | perf_free_event(event, ctx); |
bbbee908 | 12602 | |
8dc85d54 | 12603 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12604 | |
12605 | /* | |
12606 | * perf_event_release_kernel() could've stolen some of our | |
12607 | * child events and still have them on its free_list. In that | |
12608 | * case we must wait for these events to have been freed (in | |
12609 | * particular all their references to this task must've been | |
12610 | * dropped). | |
12611 | * | |
12612 | * Without this copy_process() will unconditionally free this | |
12613 | * task (irrespective of its reference count) and | |
12614 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12615 | * use-after-free. | |
12616 | * | |
12617 | * Wait for all events to drop their context reference. | |
12618 | */ | |
12619 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12620 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12621 | } |
889ff015 FW |
12622 | } |
12623 | ||
4e231c79 PZ |
12624 | void perf_event_delayed_put(struct task_struct *task) |
12625 | { | |
12626 | int ctxn; | |
12627 | ||
12628 | for_each_task_context_nr(ctxn) | |
12629 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12630 | } | |
12631 | ||
e03e7ee3 | 12632 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12633 | { |
02e5ad97 | 12634 | struct file *file = fget(fd); |
e03e7ee3 AS |
12635 | if (!file) |
12636 | return ERR_PTR(-EBADF); | |
ffe8690c | 12637 | |
e03e7ee3 AS |
12638 | if (file->f_op != &perf_fops) { |
12639 | fput(file); | |
12640 | return ERR_PTR(-EBADF); | |
12641 | } | |
ffe8690c | 12642 | |
e03e7ee3 | 12643 | return file; |
ffe8690c KX |
12644 | } |
12645 | ||
f8d959a5 YS |
12646 | const struct perf_event *perf_get_event(struct file *file) |
12647 | { | |
12648 | if (file->f_op != &perf_fops) | |
12649 | return ERR_PTR(-EINVAL); | |
12650 | ||
12651 | return file->private_data; | |
12652 | } | |
12653 | ||
ffe8690c KX |
12654 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12655 | { | |
12656 | if (!event) | |
12657 | return ERR_PTR(-EINVAL); | |
12658 | ||
12659 | return &event->attr; | |
12660 | } | |
12661 | ||
97dee4f3 | 12662 | /* |
788faab7 | 12663 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12664 | * |
12665 | * Returns: | |
12666 | * - valid pointer on success | |
12667 | * - NULL for orphaned events | |
12668 | * - IS_ERR() on error | |
97dee4f3 PZ |
12669 | */ |
12670 | static struct perf_event * | |
12671 | inherit_event(struct perf_event *parent_event, | |
12672 | struct task_struct *parent, | |
12673 | struct perf_event_context *parent_ctx, | |
12674 | struct task_struct *child, | |
12675 | struct perf_event *group_leader, | |
12676 | struct perf_event_context *child_ctx) | |
12677 | { | |
8ca2bd41 | 12678 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12679 | struct perf_event *child_event; |
cee010ec | 12680 | unsigned long flags; |
97dee4f3 PZ |
12681 | |
12682 | /* | |
12683 | * Instead of creating recursive hierarchies of events, | |
12684 | * we link inherited events back to the original parent, | |
12685 | * which has a filp for sure, which we use as the reference | |
12686 | * count: | |
12687 | */ | |
12688 | if (parent_event->parent) | |
12689 | parent_event = parent_event->parent; | |
12690 | ||
12691 | child_event = perf_event_alloc(&parent_event->attr, | |
12692 | parent_event->cpu, | |
d580ff86 | 12693 | child, |
97dee4f3 | 12694 | group_leader, parent_event, |
79dff51e | 12695 | NULL, NULL, -1); |
97dee4f3 PZ |
12696 | if (IS_ERR(child_event)) |
12697 | return child_event; | |
a6fa941d | 12698 | |
313ccb96 JO |
12699 | |
12700 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12701 | !child_ctx->task_ctx_data) { | |
12702 | struct pmu *pmu = child_event->pmu; | |
12703 | ||
ff9ff926 | 12704 | child_ctx->task_ctx_data = alloc_task_ctx_data(pmu); |
313ccb96 JO |
12705 | if (!child_ctx->task_ctx_data) { |
12706 | free_event(child_event); | |
697d8778 | 12707 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12708 | } |
12709 | } | |
12710 | ||
c6e5b732 PZ |
12711 | /* |
12712 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12713 | * must be under the same lock in order to serialize against | |
12714 | * perf_event_release_kernel(), such that either we must observe | |
12715 | * is_orphaned_event() or they will observe us on the child_list. | |
12716 | */ | |
12717 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12718 | if (is_orphaned_event(parent_event) || |
12719 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12720 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12721 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12722 | free_event(child_event); |
12723 | return NULL; | |
12724 | } | |
12725 | ||
97dee4f3 PZ |
12726 | get_ctx(child_ctx); |
12727 | ||
12728 | /* | |
12729 | * Make the child state follow the state of the parent event, | |
12730 | * not its attr.disabled bit. We hold the parent's mutex, | |
12731 | * so we won't race with perf_event_{en, dis}able_family. | |
12732 | */ | |
1929def9 | 12733 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12734 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12735 | else | |
12736 | child_event->state = PERF_EVENT_STATE_OFF; | |
12737 | ||
12738 | if (parent_event->attr.freq) { | |
12739 | u64 sample_period = parent_event->hw.sample_period; | |
12740 | struct hw_perf_event *hwc = &child_event->hw; | |
12741 | ||
12742 | hwc->sample_period = sample_period; | |
12743 | hwc->last_period = sample_period; | |
12744 | ||
12745 | local64_set(&hwc->period_left, sample_period); | |
12746 | } | |
12747 | ||
12748 | child_event->ctx = child_ctx; | |
12749 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12750 | child_event->overflow_handler_context |
12751 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12752 | |
614b6780 TG |
12753 | /* |
12754 | * Precalculate sample_data sizes | |
12755 | */ | |
12756 | perf_event__header_size(child_event); | |
6844c09d | 12757 | perf_event__id_header_size(child_event); |
614b6780 | 12758 | |
97dee4f3 PZ |
12759 | /* |
12760 | * Link it up in the child's context: | |
12761 | */ | |
cee010ec | 12762 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12763 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12764 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12765 | |
97dee4f3 PZ |
12766 | /* |
12767 | * Link this into the parent event's child list | |
12768 | */ | |
97dee4f3 PZ |
12769 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12770 | mutex_unlock(&parent_event->child_mutex); | |
12771 | ||
12772 | return child_event; | |
12773 | } | |
12774 | ||
d8a8cfc7 PZ |
12775 | /* |
12776 | * Inherits an event group. | |
12777 | * | |
12778 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12779 | * This matches with perf_event_release_kernel() removing all child events. | |
12780 | * | |
12781 | * Returns: | |
12782 | * - 0 on success | |
12783 | * - <0 on error | |
12784 | */ | |
97dee4f3 PZ |
12785 | static int inherit_group(struct perf_event *parent_event, |
12786 | struct task_struct *parent, | |
12787 | struct perf_event_context *parent_ctx, | |
12788 | struct task_struct *child, | |
12789 | struct perf_event_context *child_ctx) | |
12790 | { | |
12791 | struct perf_event *leader; | |
12792 | struct perf_event *sub; | |
12793 | struct perf_event *child_ctr; | |
12794 | ||
12795 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12796 | child, NULL, child_ctx); | |
12797 | if (IS_ERR(leader)) | |
12798 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12799 | /* |
12800 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12801 | * case inherit_event() will create individual events, similar to what | |
12802 | * perf_group_detach() would do anyway. | |
12803 | */ | |
edb39592 | 12804 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12805 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12806 | child, leader, child_ctx); | |
12807 | if (IS_ERR(child_ctr)) | |
12808 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12809 | |
00496fe5 | 12810 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12811 | !perf_get_aux_event(child_ctr, leader)) |
12812 | return -EINVAL; | |
97dee4f3 PZ |
12813 | } |
12814 | return 0; | |
889ff015 FW |
12815 | } |
12816 | ||
d8a8cfc7 PZ |
12817 | /* |
12818 | * Creates the child task context and tries to inherit the event-group. | |
12819 | * | |
12820 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12821 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12822 | * consistent with perf_event_release_kernel() removing all child events. | |
12823 | * | |
12824 | * Returns: | |
12825 | * - 0 on success | |
12826 | * - <0 on error | |
12827 | */ | |
889ff015 FW |
12828 | static int |
12829 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12830 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12831 | struct task_struct *child, int ctxn, |
889ff015 FW |
12832 | int *inherited_all) |
12833 | { | |
12834 | int ret; | |
8dc85d54 | 12835 | struct perf_event_context *child_ctx; |
889ff015 FW |
12836 | |
12837 | if (!event->attr.inherit) { | |
12838 | *inherited_all = 0; | |
12839 | return 0; | |
bbbee908 PZ |
12840 | } |
12841 | ||
fe4b04fa | 12842 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12843 | if (!child_ctx) { |
12844 | /* | |
12845 | * This is executed from the parent task context, so | |
12846 | * inherit events that have been marked for cloning. | |
12847 | * First allocate and initialize a context for the | |
12848 | * child. | |
12849 | */ | |
734df5ab | 12850 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12851 | if (!child_ctx) |
12852 | return -ENOMEM; | |
bbbee908 | 12853 | |
8dc85d54 | 12854 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12855 | } |
12856 | ||
12857 | ret = inherit_group(event, parent, parent_ctx, | |
12858 | child, child_ctx); | |
12859 | ||
12860 | if (ret) | |
12861 | *inherited_all = 0; | |
12862 | ||
12863 | return ret; | |
bbbee908 PZ |
12864 | } |
12865 | ||
9b51f66d | 12866 | /* |
cdd6c482 | 12867 | * Initialize the perf_event context in task_struct |
9b51f66d | 12868 | */ |
985c8dcb | 12869 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12870 | { |
889ff015 | 12871 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12872 | struct perf_event_context *cloned_ctx; |
12873 | struct perf_event *event; | |
9b51f66d | 12874 | struct task_struct *parent = current; |
564c2b21 | 12875 | int inherited_all = 1; |
dddd3379 | 12876 | unsigned long flags; |
6ab423e0 | 12877 | int ret = 0; |
9b51f66d | 12878 | |
8dc85d54 | 12879 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12880 | return 0; |
12881 | ||
ad3a37de | 12882 | /* |
25346b93 PM |
12883 | * If the parent's context is a clone, pin it so it won't get |
12884 | * swapped under us. | |
ad3a37de | 12885 | */ |
8dc85d54 | 12886 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12887 | if (!parent_ctx) |
12888 | return 0; | |
25346b93 | 12889 | |
ad3a37de PM |
12890 | /* |
12891 | * No need to check if parent_ctx != NULL here; since we saw | |
12892 | * it non-NULL earlier, the only reason for it to become NULL | |
12893 | * is if we exit, and since we're currently in the middle of | |
12894 | * a fork we can't be exiting at the same time. | |
12895 | */ | |
ad3a37de | 12896 | |
9b51f66d IM |
12897 | /* |
12898 | * Lock the parent list. No need to lock the child - not PID | |
12899 | * hashed yet and not running, so nobody can access it. | |
12900 | */ | |
d859e29f | 12901 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12902 | |
12903 | /* | |
12904 | * We dont have to disable NMIs - we are only looking at | |
12905 | * the list, not manipulating it: | |
12906 | */ | |
6e6804d2 | 12907 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12908 | ret = inherit_task_group(event, parent, parent_ctx, |
12909 | child, ctxn, &inherited_all); | |
889ff015 | 12910 | if (ret) |
e7cc4865 | 12911 | goto out_unlock; |
889ff015 | 12912 | } |
b93f7978 | 12913 | |
dddd3379 TG |
12914 | /* |
12915 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12916 | * to allocations, but we need to prevent rotation because | |
12917 | * rotate_ctx() will change the list from interrupt context. | |
12918 | */ | |
12919 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12920 | parent_ctx->rotate_disable = 1; | |
12921 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12922 | ||
6e6804d2 | 12923 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12924 | ret = inherit_task_group(event, parent, parent_ctx, |
12925 | child, ctxn, &inherited_all); | |
889ff015 | 12926 | if (ret) |
e7cc4865 | 12927 | goto out_unlock; |
564c2b21 PM |
12928 | } |
12929 | ||
dddd3379 TG |
12930 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12931 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12932 | |
8dc85d54 | 12933 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12934 | |
05cbaa28 | 12935 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12936 | /* |
12937 | * Mark the child context as a clone of the parent | |
12938 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12939 | * |
12940 | * Note that if the parent is a clone, the holding of | |
12941 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12942 | */ |
c5ed5145 | 12943 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12944 | if (cloned_ctx) { |
12945 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12946 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12947 | } else { |
12948 | child_ctx->parent_ctx = parent_ctx; | |
12949 | child_ctx->parent_gen = parent_ctx->generation; | |
12950 | } | |
12951 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12952 | } |
12953 | ||
c5ed5145 | 12954 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12955 | out_unlock: |
d859e29f | 12956 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12957 | |
25346b93 | 12958 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12959 | put_ctx(parent_ctx); |
ad3a37de | 12960 | |
6ab423e0 | 12961 | return ret; |
9b51f66d IM |
12962 | } |
12963 | ||
8dc85d54 PZ |
12964 | /* |
12965 | * Initialize the perf_event context in task_struct | |
12966 | */ | |
12967 | int perf_event_init_task(struct task_struct *child) | |
12968 | { | |
12969 | int ctxn, ret; | |
12970 | ||
8550d7cb ON |
12971 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12972 | mutex_init(&child->perf_event_mutex); | |
12973 | INIT_LIST_HEAD(&child->perf_event_list); | |
12974 | ||
8dc85d54 PZ |
12975 | for_each_task_context_nr(ctxn) { |
12976 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12977 | if (ret) { |
12978 | perf_event_free_task(child); | |
8dc85d54 | 12979 | return ret; |
6c72e350 | 12980 | } |
8dc85d54 PZ |
12981 | } |
12982 | ||
12983 | return 0; | |
12984 | } | |
12985 | ||
220b140b PM |
12986 | static void __init perf_event_init_all_cpus(void) |
12987 | { | |
b28ab83c | 12988 | struct swevent_htable *swhash; |
220b140b | 12989 | int cpu; |
220b140b | 12990 | |
a63fbed7 TG |
12991 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12992 | ||
220b140b | 12993 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12994 | swhash = &per_cpu(swevent_htable, cpu); |
12995 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12996 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12997 | |
12998 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12999 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 13000 | |
058fe1c0 DCC |
13001 | #ifdef CONFIG_CGROUP_PERF |
13002 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
13003 | #endif | |
f008790a | 13004 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
13005 | } |
13006 | } | |
13007 | ||
d18bf422 | 13008 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 13009 | { |
108b02cf | 13010 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 13011 | |
b28ab83c | 13012 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 13013 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
13014 | struct swevent_hlist *hlist; |
13015 | ||
b28ab83c PZ |
13016 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
13017 | WARN_ON(!hlist); | |
13018 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 13019 | } |
b28ab83c | 13020 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
13021 | } |
13022 | ||
2965faa5 | 13023 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 13024 | static void __perf_event_exit_context(void *__info) |
0793a61d | 13025 | { |
108b02cf | 13026 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
13027 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
13028 | struct perf_event *event; | |
0793a61d | 13029 | |
fae3fde6 | 13030 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 13031 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 13032 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 13033 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 13034 | raw_spin_unlock(&ctx->lock); |
0793a61d | 13035 | } |
108b02cf PZ |
13036 | |
13037 | static void perf_event_exit_cpu_context(int cpu) | |
13038 | { | |
a63fbed7 | 13039 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
13040 | struct perf_event_context *ctx; |
13041 | struct pmu *pmu; | |
108b02cf | 13042 | |
a63fbed7 TG |
13043 | mutex_lock(&pmus_lock); |
13044 | list_for_each_entry(pmu, &pmus, entry) { | |
13045 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13046 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
13047 | |
13048 | mutex_lock(&ctx->mutex); | |
13049 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 13050 | cpuctx->online = 0; |
108b02cf PZ |
13051 | mutex_unlock(&ctx->mutex); |
13052 | } | |
a63fbed7 TG |
13053 | cpumask_clear_cpu(cpu, perf_online_mask); |
13054 | mutex_unlock(&pmus_lock); | |
108b02cf | 13055 | } |
00e16c3d TG |
13056 | #else |
13057 | ||
13058 | static void perf_event_exit_cpu_context(int cpu) { } | |
13059 | ||
13060 | #endif | |
108b02cf | 13061 | |
a63fbed7 TG |
13062 | int perf_event_init_cpu(unsigned int cpu) |
13063 | { | |
13064 | struct perf_cpu_context *cpuctx; | |
13065 | struct perf_event_context *ctx; | |
13066 | struct pmu *pmu; | |
13067 | ||
13068 | perf_swevent_init_cpu(cpu); | |
13069 | ||
13070 | mutex_lock(&pmus_lock); | |
13071 | cpumask_set_cpu(cpu, perf_online_mask); | |
13072 | list_for_each_entry(pmu, &pmus, entry) { | |
13073 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13074 | ctx = &cpuctx->ctx; | |
13075 | ||
13076 | mutex_lock(&ctx->mutex); | |
13077 | cpuctx->online = 1; | |
13078 | mutex_unlock(&ctx->mutex); | |
13079 | } | |
13080 | mutex_unlock(&pmus_lock); | |
13081 | ||
13082 | return 0; | |
13083 | } | |
13084 | ||
00e16c3d | 13085 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 13086 | { |
e3703f8c | 13087 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 13088 | return 0; |
0793a61d | 13089 | } |
0793a61d | 13090 | |
c277443c PZ |
13091 | static int |
13092 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
13093 | { | |
13094 | int cpu; | |
13095 | ||
13096 | for_each_online_cpu(cpu) | |
13097 | perf_event_exit_cpu(cpu); | |
13098 | ||
13099 | return NOTIFY_OK; | |
13100 | } | |
13101 | ||
13102 | /* | |
13103 | * Run the perf reboot notifier at the very last possible moment so that | |
13104 | * the generic watchdog code runs as long as possible. | |
13105 | */ | |
13106 | static struct notifier_block perf_reboot_notifier = { | |
13107 | .notifier_call = perf_reboot, | |
13108 | .priority = INT_MIN, | |
13109 | }; | |
13110 | ||
cdd6c482 | 13111 | void __init perf_event_init(void) |
0793a61d | 13112 | { |
3c502e7a JW |
13113 | int ret; |
13114 | ||
2e80a82a PZ |
13115 | idr_init(&pmu_idr); |
13116 | ||
220b140b | 13117 | perf_event_init_all_cpus(); |
b0a873eb | 13118 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
13119 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
13120 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
13121 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 13122 | perf_tp_register(); |
00e16c3d | 13123 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 13124 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
13125 | |
13126 | ret = init_hw_breakpoint(); | |
13127 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 13128 | |
b01c3a00 JO |
13129 | /* |
13130 | * Build time assertion that we keep the data_head at the intended | |
13131 | * location. IOW, validation we got the __reserved[] size right. | |
13132 | */ | |
13133 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
13134 | != 1024); | |
0793a61d | 13135 | } |
abe43400 | 13136 | |
fd979c01 CS |
13137 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
13138 | char *page) | |
13139 | { | |
13140 | struct perf_pmu_events_attr *pmu_attr = | |
13141 | container_of(attr, struct perf_pmu_events_attr, attr); | |
13142 | ||
13143 | if (pmu_attr->event_str) | |
13144 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
13145 | ||
13146 | return 0; | |
13147 | } | |
675965b0 | 13148 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 13149 | |
abe43400 PZ |
13150 | static int __init perf_event_sysfs_init(void) |
13151 | { | |
13152 | struct pmu *pmu; | |
13153 | int ret; | |
13154 | ||
13155 | mutex_lock(&pmus_lock); | |
13156 | ||
13157 | ret = bus_register(&pmu_bus); | |
13158 | if (ret) | |
13159 | goto unlock; | |
13160 | ||
13161 | list_for_each_entry(pmu, &pmus, entry) { | |
13162 | if (!pmu->name || pmu->type < 0) | |
13163 | continue; | |
13164 | ||
13165 | ret = pmu_dev_alloc(pmu); | |
13166 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
13167 | } | |
13168 | pmu_bus_running = 1; | |
13169 | ret = 0; | |
13170 | ||
13171 | unlock: | |
13172 | mutex_unlock(&pmus_lock); | |
13173 | ||
13174 | return ret; | |
13175 | } | |
13176 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
13177 | |
13178 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
13179 | static struct cgroup_subsys_state * |
13180 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
13181 | { |
13182 | struct perf_cgroup *jc; | |
e5d1367f | 13183 | |
1b15d055 | 13184 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
13185 | if (!jc) |
13186 | return ERR_PTR(-ENOMEM); | |
13187 | ||
e5d1367f SE |
13188 | jc->info = alloc_percpu(struct perf_cgroup_info); |
13189 | if (!jc->info) { | |
13190 | kfree(jc); | |
13191 | return ERR_PTR(-ENOMEM); | |
13192 | } | |
13193 | ||
e5d1367f SE |
13194 | return &jc->css; |
13195 | } | |
13196 | ||
eb95419b | 13197 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 13198 | { |
eb95419b TH |
13199 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
13200 | ||
e5d1367f SE |
13201 | free_percpu(jc->info); |
13202 | kfree(jc); | |
13203 | } | |
13204 | ||
96aaab68 NK |
13205 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
13206 | { | |
13207 | perf_event_cgroup(css->cgroup); | |
13208 | return 0; | |
13209 | } | |
13210 | ||
e5d1367f SE |
13211 | static int __perf_cgroup_move(void *info) |
13212 | { | |
13213 | struct task_struct *task = info; | |
ddaaf4e2 | 13214 | rcu_read_lock(); |
e5d1367f | 13215 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 13216 | rcu_read_unlock(); |
e5d1367f SE |
13217 | return 0; |
13218 | } | |
13219 | ||
1f7dd3e5 | 13220 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 13221 | { |
bb9d97b6 | 13222 | struct task_struct *task; |
1f7dd3e5 | 13223 | struct cgroup_subsys_state *css; |
bb9d97b6 | 13224 | |
1f7dd3e5 | 13225 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 13226 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
13227 | } |
13228 | ||
073219e9 | 13229 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
13230 | .css_alloc = perf_cgroup_css_alloc, |
13231 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 13232 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 13233 | .attach = perf_cgroup_attach, |
968ebff1 TH |
13234 | /* |
13235 | * Implicitly enable on dfl hierarchy so that perf events can | |
13236 | * always be filtered by cgroup2 path as long as perf_event | |
13237 | * controller is not mounted on a legacy hierarchy. | |
13238 | */ | |
13239 | .implicit_on_dfl = true, | |
8cfd8147 | 13240 | .threaded = true, |
e5d1367f SE |
13241 | }; |
13242 | #endif /* CONFIG_CGROUP_PERF */ |