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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); |
f2fb6bef | 388 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 389 | |
cdd6c482 IM |
390 | static atomic_t nr_mmap_events __read_mostly; |
391 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 392 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 393 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 394 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 395 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 396 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 397 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 398 | static atomic_t nr_cgroup_events __read_mostly; |
e17d43b9 | 399 | static atomic_t nr_text_poke_events __read_mostly; |
9ee318a7 | 400 | |
108b02cf PZ |
401 | static LIST_HEAD(pmus); |
402 | static DEFINE_MUTEX(pmus_lock); | |
403 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 404 | static cpumask_var_t perf_online_mask; |
108b02cf | 405 | |
0764771d | 406 | /* |
cdd6c482 | 407 | * perf event paranoia level: |
0fbdea19 IM |
408 | * -1 - not paranoid at all |
409 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 410 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 411 | * 2 - disallow kernel profiling for unpriv |
0764771d | 412 | */ |
0161028b | 413 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 414 | |
20443384 FW |
415 | /* Minimum for 512 kiB + 1 user control page */ |
416 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
417 | |
418 | /* | |
cdd6c482 | 419 | * max perf event sample rate |
df58ab24 | 420 | */ |
14c63f17 DH |
421 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
422 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
423 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
424 | ||
425 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
426 | ||
427 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
428 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
429 | ||
d9494cb4 PZ |
430 | static int perf_sample_allowed_ns __read_mostly = |
431 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 432 | |
18ab2cd3 | 433 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
434 | { |
435 | u64 tmp = perf_sample_period_ns; | |
436 | ||
437 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
438 | tmp = div_u64(tmp, 100); |
439 | if (!tmp) | |
440 | tmp = 1; | |
441 | ||
442 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 443 | } |
163ec435 | 444 | |
8d5bce0c | 445 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 446 | |
163ec435 | 447 | int perf_proc_update_handler(struct ctl_table *table, int write, |
32927393 | 448 | void *buffer, size_t *lenp, loff_t *ppos) |
163ec435 | 449 | { |
1a51c5da SE |
450 | int ret; |
451 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
452 | /* |
453 | * If throttling is disabled don't allow the write: | |
454 | */ | |
1a51c5da | 455 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
456 | return -EINVAL; |
457 | ||
1a51c5da SE |
458 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
459 | if (ret || !write) | |
460 | return ret; | |
461 | ||
163ec435 | 462 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
463 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
464 | update_perf_cpu_limits(); | |
465 | ||
466 | return 0; | |
467 | } | |
468 | ||
469 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
470 | ||
471 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
32927393 | 472 | void *buffer, size_t *lenp, loff_t *ppos) |
14c63f17 | 473 | { |
1572e45a | 474 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
475 | |
476 | if (ret || !write) | |
477 | return ret; | |
478 | ||
b303e7c1 PZ |
479 | if (sysctl_perf_cpu_time_max_percent == 100 || |
480 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
481 | printk(KERN_WARNING |
482 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
483 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
484 | } else { | |
485 | update_perf_cpu_limits(); | |
486 | } | |
163ec435 PZ |
487 | |
488 | return 0; | |
489 | } | |
1ccd1549 | 490 | |
14c63f17 DH |
491 | /* |
492 | * perf samples are done in some very critical code paths (NMIs). | |
493 | * If they take too much CPU time, the system can lock up and not | |
494 | * get any real work done. This will drop the sample rate when | |
495 | * we detect that events are taking too long. | |
496 | */ | |
497 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 498 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 499 | |
91a612ee PZ |
500 | static u64 __report_avg; |
501 | static u64 __report_allowed; | |
502 | ||
6a02ad66 | 503 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 504 | { |
0d87d7ec | 505 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
506 | "perf: interrupt took too long (%lld > %lld), lowering " |
507 | "kernel.perf_event_max_sample_rate to %d\n", | |
508 | __report_avg, __report_allowed, | |
509 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
510 | } |
511 | ||
512 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
513 | ||
514 | void perf_sample_event_took(u64 sample_len_ns) | |
515 | { | |
91a612ee PZ |
516 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
517 | u64 running_len; | |
518 | u64 avg_len; | |
519 | u32 max; | |
14c63f17 | 520 | |
91a612ee | 521 | if (max_len == 0) |
14c63f17 DH |
522 | return; |
523 | ||
91a612ee PZ |
524 | /* Decay the counter by 1 average sample. */ |
525 | running_len = __this_cpu_read(running_sample_length); | |
526 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
527 | running_len += sample_len_ns; | |
528 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
529 | |
530 | /* | |
91a612ee PZ |
531 | * Note: this will be biased artifically low until we have |
532 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
533 | * from having to maintain a count. |
534 | */ | |
91a612ee PZ |
535 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
536 | if (avg_len <= max_len) | |
14c63f17 DH |
537 | return; |
538 | ||
91a612ee PZ |
539 | __report_avg = avg_len; |
540 | __report_allowed = max_len; | |
14c63f17 | 541 | |
91a612ee PZ |
542 | /* |
543 | * Compute a throttle threshold 25% below the current duration. | |
544 | */ | |
545 | avg_len += avg_len / 4; | |
546 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
547 | if (avg_len < max) | |
548 | max /= (u32)avg_len; | |
549 | else | |
550 | max = 1; | |
14c63f17 | 551 | |
91a612ee PZ |
552 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
553 | WRITE_ONCE(max_samples_per_tick, max); | |
554 | ||
555 | sysctl_perf_event_sample_rate = max * HZ; | |
556 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 557 | |
cd578abb | 558 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 559 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 560 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 561 | __report_avg, __report_allowed, |
cd578abb PZ |
562 | sysctl_perf_event_sample_rate); |
563 | } | |
14c63f17 DH |
564 | } |
565 | ||
cdd6c482 | 566 | static atomic64_t perf_event_id; |
a96bbc16 | 567 | |
0b3fcf17 SE |
568 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
569 | enum event_type_t event_type); | |
570 | ||
571 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
572 | enum event_type_t event_type, |
573 | struct task_struct *task); | |
574 | ||
575 | static void update_context_time(struct perf_event_context *ctx); | |
576 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 577 | |
cdd6c482 | 578 | void __weak perf_event_print_debug(void) { } |
0793a61d | 579 | |
84c79910 | 580 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 581 | { |
84c79910 | 582 | return "pmu"; |
0793a61d TG |
583 | } |
584 | ||
0b3fcf17 SE |
585 | static inline u64 perf_clock(void) |
586 | { | |
587 | return local_clock(); | |
588 | } | |
589 | ||
34f43927 PZ |
590 | static inline u64 perf_event_clock(struct perf_event *event) |
591 | { | |
592 | return event->clock(); | |
593 | } | |
594 | ||
0d3d73aa PZ |
595 | /* |
596 | * State based event timekeeping... | |
597 | * | |
598 | * The basic idea is to use event->state to determine which (if any) time | |
599 | * fields to increment with the current delta. This means we only need to | |
600 | * update timestamps when we change state or when they are explicitly requested | |
601 | * (read). | |
602 | * | |
603 | * Event groups make things a little more complicated, but not terribly so. The | |
604 | * rules for a group are that if the group leader is OFF the entire group is | |
605 | * OFF, irrespecive of what the group member states are. This results in | |
606 | * __perf_effective_state(). | |
607 | * | |
608 | * A futher ramification is that when a group leader flips between OFF and | |
609 | * !OFF, we need to update all group member times. | |
610 | * | |
611 | * | |
612 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
613 | * need to make sure the relevant context time is updated before we try and | |
614 | * update our timestamps. | |
615 | */ | |
616 | ||
617 | static __always_inline enum perf_event_state | |
618 | __perf_effective_state(struct perf_event *event) | |
619 | { | |
620 | struct perf_event *leader = event->group_leader; | |
621 | ||
622 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
623 | return leader->state; | |
624 | ||
625 | return event->state; | |
626 | } | |
627 | ||
628 | static __always_inline void | |
629 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
630 | { | |
631 | enum perf_event_state state = __perf_effective_state(event); | |
632 | u64 delta = now - event->tstamp; | |
633 | ||
634 | *enabled = event->total_time_enabled; | |
635 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
636 | *enabled += delta; | |
637 | ||
638 | *running = event->total_time_running; | |
639 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
640 | *running += delta; | |
641 | } | |
642 | ||
643 | static void perf_event_update_time(struct perf_event *event) | |
644 | { | |
645 | u64 now = perf_event_time(event); | |
646 | ||
647 | __perf_update_times(event, now, &event->total_time_enabled, | |
648 | &event->total_time_running); | |
649 | event->tstamp = now; | |
650 | } | |
651 | ||
652 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
653 | { | |
654 | struct perf_event *sibling; | |
655 | ||
edb39592 | 656 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
657 | perf_event_update_time(sibling); |
658 | } | |
659 | ||
660 | static void | |
661 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
662 | { | |
663 | if (event->state == state) | |
664 | return; | |
665 | ||
666 | perf_event_update_time(event); | |
667 | /* | |
668 | * If a group leader gets enabled/disabled all its siblings | |
669 | * are affected too. | |
670 | */ | |
671 | if ((event->state < 0) ^ (state < 0)) | |
672 | perf_event_update_sibling_time(event); | |
673 | ||
674 | WRITE_ONCE(event->state, state); | |
675 | } | |
676 | ||
e5d1367f SE |
677 | #ifdef CONFIG_CGROUP_PERF |
678 | ||
e5d1367f SE |
679 | static inline bool |
680 | perf_cgroup_match(struct perf_event *event) | |
681 | { | |
682 | struct perf_event_context *ctx = event->ctx; | |
683 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
684 | ||
ef824fa1 TH |
685 | /* @event doesn't care about cgroup */ |
686 | if (!event->cgrp) | |
687 | return true; | |
688 | ||
689 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
690 | if (!cpuctx->cgrp) | |
691 | return false; | |
692 | ||
693 | /* | |
694 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
695 | * also enabled for all its descendant cgroups. If @cpuctx's | |
696 | * cgroup is a descendant of @event's (the test covers identity | |
697 | * case), it's a match. | |
698 | */ | |
699 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
700 | event->cgrp->css.cgroup); | |
e5d1367f SE |
701 | } |
702 | ||
e5d1367f SE |
703 | static inline void perf_detach_cgroup(struct perf_event *event) |
704 | { | |
4e2ba650 | 705 | css_put(&event->cgrp->css); |
e5d1367f SE |
706 | event->cgrp = NULL; |
707 | } | |
708 | ||
709 | static inline int is_cgroup_event(struct perf_event *event) | |
710 | { | |
711 | return event->cgrp != NULL; | |
712 | } | |
713 | ||
714 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
715 | { | |
716 | struct perf_cgroup_info *t; | |
717 | ||
718 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
719 | return t->time; | |
720 | } | |
721 | ||
722 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
723 | { | |
724 | struct perf_cgroup_info *info; | |
725 | u64 now; | |
726 | ||
727 | now = perf_clock(); | |
728 | ||
729 | info = this_cpu_ptr(cgrp->info); | |
730 | ||
731 | info->time += now - info->timestamp; | |
732 | info->timestamp = now; | |
733 | } | |
734 | ||
735 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
736 | { | |
c917e0f2 SL |
737 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
738 | struct cgroup_subsys_state *css; | |
739 | ||
740 | if (cgrp) { | |
741 | for (css = &cgrp->css; css; css = css->parent) { | |
742 | cgrp = container_of(css, struct perf_cgroup, css); | |
743 | __update_cgrp_time(cgrp); | |
744 | } | |
745 | } | |
e5d1367f SE |
746 | } |
747 | ||
748 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
749 | { | |
3f7cce3c SE |
750 | struct perf_cgroup *cgrp; |
751 | ||
e5d1367f | 752 | /* |
3f7cce3c SE |
753 | * ensure we access cgroup data only when needed and |
754 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 755 | */ |
3f7cce3c | 756 | if (!is_cgroup_event(event)) |
e5d1367f SE |
757 | return; |
758 | ||
614e4c4e | 759 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
760 | /* |
761 | * Do not update time when cgroup is not active | |
762 | */ | |
28fa741c | 763 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 764 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
765 | } |
766 | ||
767 | static inline void | |
3f7cce3c SE |
768 | perf_cgroup_set_timestamp(struct task_struct *task, |
769 | struct perf_event_context *ctx) | |
e5d1367f SE |
770 | { |
771 | struct perf_cgroup *cgrp; | |
772 | struct perf_cgroup_info *info; | |
c917e0f2 | 773 | struct cgroup_subsys_state *css; |
e5d1367f | 774 | |
3f7cce3c SE |
775 | /* |
776 | * ctx->lock held by caller | |
777 | * ensure we do not access cgroup data | |
778 | * unless we have the cgroup pinned (css_get) | |
779 | */ | |
780 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
781 | return; |
782 | ||
614e4c4e | 783 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
784 | |
785 | for (css = &cgrp->css; css; css = css->parent) { | |
786 | cgrp = container_of(css, struct perf_cgroup, css); | |
787 | info = this_cpu_ptr(cgrp->info); | |
788 | info->timestamp = ctx->timestamp; | |
789 | } | |
e5d1367f SE |
790 | } |
791 | ||
058fe1c0 DCC |
792 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
793 | ||
e5d1367f SE |
794 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
795 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
796 | ||
797 | /* | |
798 | * reschedule events based on the cgroup constraint of task. | |
799 | * | |
800 | * mode SWOUT : schedule out everything | |
801 | * mode SWIN : schedule in based on cgroup for next | |
802 | */ | |
18ab2cd3 | 803 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
804 | { |
805 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 806 | struct list_head *list; |
e5d1367f SE |
807 | unsigned long flags; |
808 | ||
809 | /* | |
058fe1c0 DCC |
810 | * Disable interrupts and preemption to avoid this CPU's |
811 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
812 | */ |
813 | local_irq_save(flags); | |
814 | ||
058fe1c0 DCC |
815 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
816 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
817 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 818 | |
058fe1c0 DCC |
819 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
820 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 821 | |
058fe1c0 DCC |
822 | if (mode & PERF_CGROUP_SWOUT) { |
823 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
824 | /* | |
825 | * must not be done before ctxswout due | |
826 | * to event_filter_match() in event_sched_out() | |
827 | */ | |
828 | cpuctx->cgrp = NULL; | |
829 | } | |
e5d1367f | 830 | |
058fe1c0 DCC |
831 | if (mode & PERF_CGROUP_SWIN) { |
832 | WARN_ON_ONCE(cpuctx->cgrp); | |
833 | /* | |
834 | * set cgrp before ctxsw in to allow | |
835 | * event_filter_match() to not have to pass | |
836 | * task around | |
837 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
838 | * because cgorup events are only per-cpu | |
839 | */ | |
840 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
841 | &cpuctx->ctx); | |
842 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 843 | } |
058fe1c0 DCC |
844 | perf_pmu_enable(cpuctx->ctx.pmu); |
845 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
846 | } |
847 | ||
e5d1367f SE |
848 | local_irq_restore(flags); |
849 | } | |
850 | ||
a8d757ef SE |
851 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
852 | struct task_struct *next) | |
e5d1367f | 853 | { |
a8d757ef SE |
854 | struct perf_cgroup *cgrp1; |
855 | struct perf_cgroup *cgrp2 = NULL; | |
856 | ||
ddaaf4e2 | 857 | rcu_read_lock(); |
a8d757ef SE |
858 | /* |
859 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
860 | * we do not need to pass the ctx here because we know |
861 | * we are holding the rcu lock | |
a8d757ef | 862 | */ |
614e4c4e | 863 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 864 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
865 | |
866 | /* | |
867 | * only schedule out current cgroup events if we know | |
868 | * that we are switching to a different cgroup. Otherwise, | |
869 | * do no touch the cgroup events. | |
870 | */ | |
871 | if (cgrp1 != cgrp2) | |
872 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
873 | |
874 | rcu_read_unlock(); | |
e5d1367f SE |
875 | } |
876 | ||
a8d757ef SE |
877 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
878 | struct task_struct *task) | |
e5d1367f | 879 | { |
a8d757ef SE |
880 | struct perf_cgroup *cgrp1; |
881 | struct perf_cgroup *cgrp2 = NULL; | |
882 | ||
ddaaf4e2 | 883 | rcu_read_lock(); |
a8d757ef SE |
884 | /* |
885 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
886 | * we do not need to pass the ctx here because we know |
887 | * we are holding the rcu lock | |
a8d757ef | 888 | */ |
614e4c4e | 889 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 890 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
891 | |
892 | /* | |
893 | * only need to schedule in cgroup events if we are changing | |
894 | * cgroup during ctxsw. Cgroup events were not scheduled | |
895 | * out of ctxsw out if that was not the case. | |
896 | */ | |
897 | if (cgrp1 != cgrp2) | |
898 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
899 | |
900 | rcu_read_unlock(); | |
e5d1367f SE |
901 | } |
902 | ||
c2283c93 IR |
903 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
904 | struct cgroup_subsys_state *css) | |
905 | { | |
906 | struct perf_cpu_context *cpuctx; | |
907 | struct perf_event **storage; | |
908 | int cpu, heap_size, ret = 0; | |
909 | ||
910 | /* | |
911 | * Allow storage to have sufficent space for an iterator for each | |
912 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
913 | */ | |
914 | for (heap_size = 1; css; css = css->parent) | |
915 | heap_size++; | |
916 | ||
917 | for_each_possible_cpu(cpu) { | |
918 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
919 | if (heap_size <= cpuctx->heap_size) | |
920 | continue; | |
921 | ||
922 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
923 | GFP_KERNEL, cpu_to_node(cpu)); | |
924 | if (!storage) { | |
925 | ret = -ENOMEM; | |
926 | break; | |
927 | } | |
928 | ||
929 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
930 | if (cpuctx->heap_size < heap_size) { | |
931 | swap(cpuctx->heap, storage); | |
932 | if (storage == cpuctx->heap_default) | |
933 | storage = NULL; | |
934 | cpuctx->heap_size = heap_size; | |
935 | } | |
936 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
937 | ||
938 | kfree(storage); | |
939 | } | |
940 | ||
941 | return ret; | |
942 | } | |
943 | ||
e5d1367f SE |
944 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
945 | struct perf_event_attr *attr, | |
946 | struct perf_event *group_leader) | |
947 | { | |
948 | struct perf_cgroup *cgrp; | |
949 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
950 | struct fd f = fdget(fd); |
951 | int ret = 0; | |
e5d1367f | 952 | |
2903ff01 | 953 | if (!f.file) |
e5d1367f SE |
954 | return -EBADF; |
955 | ||
b583043e | 956 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 957 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
958 | if (IS_ERR(css)) { |
959 | ret = PTR_ERR(css); | |
960 | goto out; | |
961 | } | |
e5d1367f | 962 | |
c2283c93 IR |
963 | ret = perf_cgroup_ensure_storage(event, css); |
964 | if (ret) | |
965 | goto out; | |
966 | ||
e5d1367f SE |
967 | cgrp = container_of(css, struct perf_cgroup, css); |
968 | event->cgrp = cgrp; | |
969 | ||
970 | /* | |
971 | * all events in a group must monitor | |
972 | * the same cgroup because a task belongs | |
973 | * to only one perf cgroup at a time | |
974 | */ | |
975 | if (group_leader && group_leader->cgrp != cgrp) { | |
976 | perf_detach_cgroup(event); | |
977 | ret = -EINVAL; | |
e5d1367f | 978 | } |
3db272c0 | 979 | out: |
2903ff01 | 980 | fdput(f); |
e5d1367f SE |
981 | return ret; |
982 | } | |
983 | ||
984 | static inline void | |
985 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
986 | { | |
987 | struct perf_cgroup_info *t; | |
988 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
989 | event->shadow_ctx_time = now - t->timestamp; | |
990 | } | |
991 | ||
db4a8356 | 992 | static inline void |
33238c50 | 993 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
994 | { |
995 | struct perf_cpu_context *cpuctx; | |
996 | ||
997 | if (!is_cgroup_event(event)) | |
998 | return; | |
999 | ||
db4a8356 DCC |
1000 | /* |
1001 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1002 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1003 | */ |
07c59729 | 1004 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1005 | |
1006 | /* | |
1007 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1008 | * matching the event's cgroup, we must do this for every new event, | |
1009 | * because if the first would mismatch, the second would not try again | |
1010 | * and we would leave cpuctx->cgrp unset. | |
1011 | */ | |
33238c50 | 1012 | if (ctx->is_active && !cpuctx->cgrp) { |
be96b316 TH |
1013 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1014 | ||
be96b316 TH |
1015 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1016 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1017 | } |
33801b94 | 1018 | |
33238c50 | 1019 | if (ctx->nr_cgroups++) |
33801b94 | 1020 | return; |
33238c50 PZ |
1021 | |
1022 | list_add(&cpuctx->cgrp_cpuctx_entry, | |
1023 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
1024 | } | |
1025 | ||
1026 | static inline void | |
1027 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1028 | { | |
1029 | struct perf_cpu_context *cpuctx; | |
1030 | ||
1031 | if (!is_cgroup_event(event)) | |
33801b94 | 1032 | return; |
1033 | ||
33238c50 PZ |
1034 | /* |
1035 | * Because cgroup events are always per-cpu events, | |
1036 | * @ctx == &cpuctx->ctx. | |
1037 | */ | |
1038 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); | |
1039 | ||
1040 | if (--ctx->nr_cgroups) | |
1041 | return; | |
1042 | ||
1043 | if (ctx->is_active && cpuctx->cgrp) | |
33801b94 | 1044 | cpuctx->cgrp = NULL; |
1045 | ||
33238c50 | 1046 | list_del(&cpuctx->cgrp_cpuctx_entry); |
db4a8356 DCC |
1047 | } |
1048 | ||
e5d1367f SE |
1049 | #else /* !CONFIG_CGROUP_PERF */ |
1050 | ||
1051 | static inline bool | |
1052 | perf_cgroup_match(struct perf_event *event) | |
1053 | { | |
1054 | return true; | |
1055 | } | |
1056 | ||
1057 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1058 | {} | |
1059 | ||
1060 | static inline int is_cgroup_event(struct perf_event *event) | |
1061 | { | |
1062 | return 0; | |
1063 | } | |
1064 | ||
e5d1367f SE |
1065 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1066 | { | |
1067 | } | |
1068 | ||
1069 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1070 | { | |
1071 | } | |
1072 | ||
a8d757ef SE |
1073 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1074 | struct task_struct *next) | |
e5d1367f SE |
1075 | { |
1076 | } | |
1077 | ||
a8d757ef SE |
1078 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1079 | struct task_struct *task) | |
e5d1367f SE |
1080 | { |
1081 | } | |
1082 | ||
1083 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1084 | struct perf_event_attr *attr, | |
1085 | struct perf_event *group_leader) | |
1086 | { | |
1087 | return -EINVAL; | |
1088 | } | |
1089 | ||
1090 | static inline void | |
3f7cce3c SE |
1091 | perf_cgroup_set_timestamp(struct task_struct *task, |
1092 | struct perf_event_context *ctx) | |
e5d1367f SE |
1093 | { |
1094 | } | |
1095 | ||
d00dbd29 | 1096 | static inline void |
e5d1367f SE |
1097 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1098 | { | |
1099 | } | |
1100 | ||
1101 | static inline void | |
1102 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1103 | { | |
1104 | } | |
1105 | ||
1106 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1107 | { | |
1108 | return 0; | |
1109 | } | |
1110 | ||
db4a8356 | 1111 | static inline void |
33238c50 | 1112 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1113 | { |
1114 | } | |
1115 | ||
33238c50 PZ |
1116 | static inline void |
1117 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1118 | { | |
1119 | } | |
e5d1367f SE |
1120 | #endif |
1121 | ||
9e630205 SE |
1122 | /* |
1123 | * set default to be dependent on timer tick just | |
1124 | * like original code | |
1125 | */ | |
1126 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1127 | /* | |
8a1115ff | 1128 | * function must be called with interrupts disabled |
9e630205 | 1129 | */ |
272325c4 | 1130 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1131 | { |
1132 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1133 | bool rotations; |
9e630205 | 1134 | |
16444645 | 1135 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1136 | |
1137 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1138 | rotations = perf_rotate_context(cpuctx); |
1139 | ||
4cfafd30 PZ |
1140 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1141 | if (rotations) | |
9e630205 | 1142 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1143 | else |
1144 | cpuctx->hrtimer_active = 0; | |
1145 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1146 | |
4cfafd30 | 1147 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1148 | } |
1149 | ||
272325c4 | 1150 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1151 | { |
272325c4 | 1152 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1153 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1154 | u64 interval; |
9e630205 SE |
1155 | |
1156 | /* no multiplexing needed for SW PMU */ | |
1157 | if (pmu->task_ctx_nr == perf_sw_context) | |
1158 | return; | |
1159 | ||
62b85639 SE |
1160 | /* |
1161 | * check default is sane, if not set then force to | |
1162 | * default interval (1/tick) | |
1163 | */ | |
272325c4 PZ |
1164 | interval = pmu->hrtimer_interval_ms; |
1165 | if (interval < 1) | |
1166 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1167 | |
272325c4 | 1168 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1169 | |
4cfafd30 | 1170 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1171 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1172 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1173 | } |
1174 | ||
272325c4 | 1175 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1176 | { |
272325c4 | 1177 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1178 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1179 | unsigned long flags; |
9e630205 SE |
1180 | |
1181 | /* not for SW PMU */ | |
1182 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1183 | return 0; |
9e630205 | 1184 | |
4cfafd30 PZ |
1185 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1186 | if (!cpuctx->hrtimer_active) { | |
1187 | cpuctx->hrtimer_active = 1; | |
1188 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1189 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1190 | } |
1191 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1192 | |
272325c4 | 1193 | return 0; |
9e630205 SE |
1194 | } |
1195 | ||
33696fc0 | 1196 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1197 | { |
33696fc0 PZ |
1198 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1199 | if (!(*count)++) | |
1200 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1201 | } |
9e35ad38 | 1202 | |
33696fc0 | 1203 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1204 | { |
33696fc0 PZ |
1205 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1206 | if (!--(*count)) | |
1207 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1208 | } |
9e35ad38 | 1209 | |
2fde4f94 | 1210 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1211 | |
1212 | /* | |
2fde4f94 MR |
1213 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1214 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1215 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1216 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1217 | */ |
2fde4f94 | 1218 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1219 | { |
2fde4f94 | 1220 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1221 | |
16444645 | 1222 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1223 | |
2fde4f94 MR |
1224 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1225 | ||
1226 | list_add(&ctx->active_ctx_list, head); | |
1227 | } | |
1228 | ||
1229 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1230 | { | |
16444645 | 1231 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1232 | |
1233 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1234 | ||
1235 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1236 | } |
9e35ad38 | 1237 | |
cdd6c482 | 1238 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1239 | { |
8c94abbb | 1240 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1241 | } |
1242 | ||
ff9ff926 KL |
1243 | static void *alloc_task_ctx_data(struct pmu *pmu) |
1244 | { | |
217c2a63 KL |
1245 | if (pmu->task_ctx_cache) |
1246 | return kmem_cache_zalloc(pmu->task_ctx_cache, GFP_KERNEL); | |
1247 | ||
5a09928d | 1248 | return NULL; |
ff9ff926 KL |
1249 | } |
1250 | ||
1251 | static void free_task_ctx_data(struct pmu *pmu, void *task_ctx_data) | |
1252 | { | |
217c2a63 KL |
1253 | if (pmu->task_ctx_cache && task_ctx_data) |
1254 | kmem_cache_free(pmu->task_ctx_cache, task_ctx_data); | |
ff9ff926 KL |
1255 | } |
1256 | ||
4af57ef2 YZ |
1257 | static void free_ctx(struct rcu_head *head) |
1258 | { | |
1259 | struct perf_event_context *ctx; | |
1260 | ||
1261 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
ff9ff926 | 1262 | free_task_ctx_data(ctx->pmu, ctx->task_ctx_data); |
4af57ef2 YZ |
1263 | kfree(ctx); |
1264 | } | |
1265 | ||
cdd6c482 | 1266 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1267 | { |
8c94abbb | 1268 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1269 | if (ctx->parent_ctx) |
1270 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1271 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1272 | put_task_struct(ctx->task); |
4af57ef2 | 1273 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1274 | } |
a63eaf34 PM |
1275 | } |
1276 | ||
f63a8daa PZ |
1277 | /* |
1278 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1279 | * perf_pmu_migrate_context() we need some magic. | |
1280 | * | |
1281 | * Those places that change perf_event::ctx will hold both | |
1282 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1283 | * | |
8b10c5e2 PZ |
1284 | * Lock ordering is by mutex address. There are two other sites where |
1285 | * perf_event_context::mutex nests and those are: | |
1286 | * | |
1287 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1288 | * perf_event_exit_event() |
1289 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1290 | * |
1291 | * - perf_event_init_context() [ parent, 0 ] | |
1292 | * inherit_task_group() | |
1293 | * inherit_group() | |
1294 | * inherit_event() | |
1295 | * perf_event_alloc() | |
1296 | * perf_init_event() | |
1297 | * perf_try_init_event() [ child , 1 ] | |
1298 | * | |
1299 | * While it appears there is an obvious deadlock here -- the parent and child | |
1300 | * nesting levels are inverted between the two. This is in fact safe because | |
1301 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1302 | * spawning task cannot (yet) exit. | |
1303 | * | |
1304 | * But remember that that these are parent<->child context relations, and | |
1305 | * migration does not affect children, therefore these two orderings should not | |
1306 | * interact. | |
f63a8daa PZ |
1307 | * |
1308 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1309 | * because the sys_perf_event_open() case will install a new event and break | |
1310 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1311 | * concerned with cpuctx and that doesn't have children. | |
1312 | * | |
1313 | * The places that change perf_event::ctx will issue: | |
1314 | * | |
1315 | * perf_remove_from_context(); | |
1316 | * synchronize_rcu(); | |
1317 | * perf_install_in_context(); | |
1318 | * | |
1319 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1320 | * quiesce the event, after which we can install it in the new location. This | |
1321 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1322 | * while in transit. Therefore all such accessors should also acquire | |
1323 | * perf_event_context::mutex to serialize against this. | |
1324 | * | |
1325 | * However; because event->ctx can change while we're waiting to acquire | |
1326 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1327 | * function. | |
1328 | * | |
1329 | * Lock order: | |
69143038 | 1330 | * exec_update_mutex |
f63a8daa PZ |
1331 | * task_struct::perf_event_mutex |
1332 | * perf_event_context::mutex | |
f63a8daa | 1333 | * perf_event::child_mutex; |
07c4a776 | 1334 | * perf_event_context::lock |
f63a8daa | 1335 | * perf_event::mmap_mutex |
c1e8d7c6 | 1336 | * mmap_lock |
18736eef | 1337 | * perf_addr_filters_head::lock |
82d94856 PZ |
1338 | * |
1339 | * cpu_hotplug_lock | |
1340 | * pmus_lock | |
1341 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1342 | */ |
a83fe28e PZ |
1343 | static struct perf_event_context * |
1344 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1345 | { |
1346 | struct perf_event_context *ctx; | |
1347 | ||
1348 | again: | |
1349 | rcu_read_lock(); | |
6aa7de05 | 1350 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1351 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1352 | rcu_read_unlock(); |
1353 | goto again; | |
1354 | } | |
1355 | rcu_read_unlock(); | |
1356 | ||
a83fe28e | 1357 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1358 | if (event->ctx != ctx) { |
1359 | mutex_unlock(&ctx->mutex); | |
1360 | put_ctx(ctx); | |
1361 | goto again; | |
1362 | } | |
1363 | ||
1364 | return ctx; | |
1365 | } | |
1366 | ||
a83fe28e PZ |
1367 | static inline struct perf_event_context * |
1368 | perf_event_ctx_lock(struct perf_event *event) | |
1369 | { | |
1370 | return perf_event_ctx_lock_nested(event, 0); | |
1371 | } | |
1372 | ||
f63a8daa PZ |
1373 | static void perf_event_ctx_unlock(struct perf_event *event, |
1374 | struct perf_event_context *ctx) | |
1375 | { | |
1376 | mutex_unlock(&ctx->mutex); | |
1377 | put_ctx(ctx); | |
1378 | } | |
1379 | ||
211de6eb PZ |
1380 | /* |
1381 | * This must be done under the ctx->lock, such as to serialize against | |
1382 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1383 | * calling scheduler related locks and ctx->lock nests inside those. | |
1384 | */ | |
1385 | static __must_check struct perf_event_context * | |
1386 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1387 | { |
211de6eb PZ |
1388 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1389 | ||
1390 | lockdep_assert_held(&ctx->lock); | |
1391 | ||
1392 | if (parent_ctx) | |
71a851b4 | 1393 | ctx->parent_ctx = NULL; |
5a3126d4 | 1394 | ctx->generation++; |
211de6eb PZ |
1395 | |
1396 | return parent_ctx; | |
71a851b4 PZ |
1397 | } |
1398 | ||
1d953111 ON |
1399 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1400 | enum pid_type type) | |
6844c09d | 1401 | { |
1d953111 | 1402 | u32 nr; |
6844c09d ACM |
1403 | /* |
1404 | * only top level events have the pid namespace they were created in | |
1405 | */ | |
1406 | if (event->parent) | |
1407 | event = event->parent; | |
1408 | ||
1d953111 ON |
1409 | nr = __task_pid_nr_ns(p, type, event->ns); |
1410 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1411 | if (!nr && !pid_alive(p)) | |
1412 | nr = -1; | |
1413 | return nr; | |
6844c09d ACM |
1414 | } |
1415 | ||
1d953111 | 1416 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1417 | { |
6883f81a | 1418 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1419 | } |
6844c09d | 1420 | |
1d953111 ON |
1421 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1422 | { | |
1423 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1424 | } |
1425 | ||
7f453c24 | 1426 | /* |
cdd6c482 | 1427 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1428 | * to userspace. |
1429 | */ | |
cdd6c482 | 1430 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1431 | { |
cdd6c482 | 1432 | u64 id = event->id; |
7f453c24 | 1433 | |
cdd6c482 IM |
1434 | if (event->parent) |
1435 | id = event->parent->id; | |
7f453c24 PZ |
1436 | |
1437 | return id; | |
1438 | } | |
1439 | ||
25346b93 | 1440 | /* |
cdd6c482 | 1441 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1442 | * |
25346b93 PM |
1443 | * This has to cope with with the fact that until it is locked, |
1444 | * the context could get moved to another task. | |
1445 | */ | |
cdd6c482 | 1446 | static struct perf_event_context * |
8dc85d54 | 1447 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1448 | { |
cdd6c482 | 1449 | struct perf_event_context *ctx; |
25346b93 | 1450 | |
9ed6060d | 1451 | retry: |
058ebd0e PZ |
1452 | /* |
1453 | * One of the few rules of preemptible RCU is that one cannot do | |
1454 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1455 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1456 | * rcu_read_unlock_special(). |
1457 | * | |
1458 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1459 | * side critical section has interrupts disabled. |
058ebd0e | 1460 | */ |
2fd59077 | 1461 | local_irq_save(*flags); |
058ebd0e | 1462 | rcu_read_lock(); |
8dc85d54 | 1463 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1464 | if (ctx) { |
1465 | /* | |
1466 | * If this context is a clone of another, it might | |
1467 | * get swapped for another underneath us by | |
cdd6c482 | 1468 | * perf_event_task_sched_out, though the |
25346b93 PM |
1469 | * rcu_read_lock() protects us from any context |
1470 | * getting freed. Lock the context and check if it | |
1471 | * got swapped before we could get the lock, and retry | |
1472 | * if so. If we locked the right context, then it | |
1473 | * can't get swapped on us any more. | |
1474 | */ | |
2fd59077 | 1475 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1476 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1477 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1478 | rcu_read_unlock(); |
2fd59077 | 1479 | local_irq_restore(*flags); |
25346b93 PM |
1480 | goto retry; |
1481 | } | |
b49a9e7e | 1482 | |
63b6da39 | 1483 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1484 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1485 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1486 | ctx = NULL; |
828b6f0e PZ |
1487 | } else { |
1488 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1489 | } |
25346b93 PM |
1490 | } |
1491 | rcu_read_unlock(); | |
2fd59077 PM |
1492 | if (!ctx) |
1493 | local_irq_restore(*flags); | |
25346b93 PM |
1494 | return ctx; |
1495 | } | |
1496 | ||
1497 | /* | |
1498 | * Get the context for a task and increment its pin_count so it | |
1499 | * can't get swapped to another task. This also increments its | |
1500 | * reference count so that the context can't get freed. | |
1501 | */ | |
8dc85d54 PZ |
1502 | static struct perf_event_context * |
1503 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1504 | { |
cdd6c482 | 1505 | struct perf_event_context *ctx; |
25346b93 PM |
1506 | unsigned long flags; |
1507 | ||
8dc85d54 | 1508 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1509 | if (ctx) { |
1510 | ++ctx->pin_count; | |
e625cce1 | 1511 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1512 | } |
1513 | return ctx; | |
1514 | } | |
1515 | ||
cdd6c482 | 1516 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1517 | { |
1518 | unsigned long flags; | |
1519 | ||
e625cce1 | 1520 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1521 | --ctx->pin_count; |
e625cce1 | 1522 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1523 | } |
1524 | ||
f67218c3 PZ |
1525 | /* |
1526 | * Update the record of the current time in a context. | |
1527 | */ | |
1528 | static void update_context_time(struct perf_event_context *ctx) | |
1529 | { | |
1530 | u64 now = perf_clock(); | |
1531 | ||
1532 | ctx->time += now - ctx->timestamp; | |
1533 | ctx->timestamp = now; | |
1534 | } | |
1535 | ||
4158755d SE |
1536 | static u64 perf_event_time(struct perf_event *event) |
1537 | { | |
1538 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1539 | |
1540 | if (is_cgroup_event(event)) | |
1541 | return perf_cgroup_event_time(event); | |
1542 | ||
4158755d SE |
1543 | return ctx ? ctx->time : 0; |
1544 | } | |
1545 | ||
487f05e1 AS |
1546 | static enum event_type_t get_event_type(struct perf_event *event) |
1547 | { | |
1548 | struct perf_event_context *ctx = event->ctx; | |
1549 | enum event_type_t event_type; | |
1550 | ||
1551 | lockdep_assert_held(&ctx->lock); | |
1552 | ||
3bda69c1 AS |
1553 | /* |
1554 | * It's 'group type', really, because if our group leader is | |
1555 | * pinned, so are we. | |
1556 | */ | |
1557 | if (event->group_leader != event) | |
1558 | event = event->group_leader; | |
1559 | ||
487f05e1 AS |
1560 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1561 | if (!ctx->task) | |
1562 | event_type |= EVENT_CPU; | |
1563 | ||
1564 | return event_type; | |
1565 | } | |
1566 | ||
8e1a2031 | 1567 | /* |
161c85fa | 1568 | * Helper function to initialize event group nodes. |
8e1a2031 | 1569 | */ |
161c85fa | 1570 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1571 | { |
1572 | RB_CLEAR_NODE(&event->group_node); | |
1573 | event->group_index = 0; | |
1574 | } | |
1575 | ||
1576 | /* | |
1577 | * Extract pinned or flexible groups from the context | |
161c85fa | 1578 | * based on event attrs bits. |
8e1a2031 AB |
1579 | */ |
1580 | static struct perf_event_groups * | |
1581 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1582 | { |
1583 | if (event->attr.pinned) | |
1584 | return &ctx->pinned_groups; | |
1585 | else | |
1586 | return &ctx->flexible_groups; | |
1587 | } | |
1588 | ||
8e1a2031 | 1589 | /* |
161c85fa | 1590 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1591 | */ |
161c85fa | 1592 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1593 | { |
1594 | groups->tree = RB_ROOT; | |
1595 | groups->index = 0; | |
1596 | } | |
1597 | ||
1598 | /* | |
1599 | * Compare function for event groups; | |
161c85fa PZ |
1600 | * |
1601 | * Implements complex key that first sorts by CPU and then by virtual index | |
1602 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1603 | */ |
161c85fa PZ |
1604 | static bool |
1605 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1606 | { |
161c85fa PZ |
1607 | if (left->cpu < right->cpu) |
1608 | return true; | |
1609 | if (left->cpu > right->cpu) | |
1610 | return false; | |
1611 | ||
95ed6c70 IR |
1612 | #ifdef CONFIG_CGROUP_PERF |
1613 | if (left->cgrp != right->cgrp) { | |
1614 | if (!left->cgrp || !left->cgrp->css.cgroup) { | |
1615 | /* | |
1616 | * Left has no cgroup but right does, no cgroups come | |
1617 | * first. | |
1618 | */ | |
1619 | return true; | |
1620 | } | |
a6763625 | 1621 | if (!right->cgrp || !right->cgrp->css.cgroup) { |
95ed6c70 IR |
1622 | /* |
1623 | * Right has no cgroup but left does, no cgroups come | |
1624 | * first. | |
1625 | */ | |
1626 | return false; | |
1627 | } | |
1628 | /* Two dissimilar cgroups, order by id. */ | |
1629 | if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) | |
1630 | return true; | |
1631 | ||
1632 | return false; | |
1633 | } | |
1634 | #endif | |
1635 | ||
161c85fa PZ |
1636 | if (left->group_index < right->group_index) |
1637 | return true; | |
1638 | if (left->group_index > right->group_index) | |
1639 | return false; | |
1640 | ||
1641 | return false; | |
8e1a2031 AB |
1642 | } |
1643 | ||
1644 | /* | |
161c85fa PZ |
1645 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1646 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1647 | * subtree. | |
8e1a2031 AB |
1648 | */ |
1649 | static void | |
1650 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1651 | struct perf_event *event) |
8e1a2031 AB |
1652 | { |
1653 | struct perf_event *node_event; | |
1654 | struct rb_node *parent; | |
1655 | struct rb_node **node; | |
1656 | ||
1657 | event->group_index = ++groups->index; | |
1658 | ||
1659 | node = &groups->tree.rb_node; | |
1660 | parent = *node; | |
1661 | ||
1662 | while (*node) { | |
1663 | parent = *node; | |
161c85fa | 1664 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1665 | |
1666 | if (perf_event_groups_less(event, node_event)) | |
1667 | node = &parent->rb_left; | |
1668 | else | |
1669 | node = &parent->rb_right; | |
1670 | } | |
1671 | ||
1672 | rb_link_node(&event->group_node, parent, node); | |
1673 | rb_insert_color(&event->group_node, &groups->tree); | |
1674 | } | |
1675 | ||
1676 | /* | |
161c85fa | 1677 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1678 | */ |
1679 | static void | |
1680 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1681 | { | |
1682 | struct perf_event_groups *groups; | |
1683 | ||
1684 | groups = get_event_groups(event, ctx); | |
1685 | perf_event_groups_insert(groups, event); | |
1686 | } | |
1687 | ||
1688 | /* | |
161c85fa | 1689 | * Delete a group from a tree. |
8e1a2031 AB |
1690 | */ |
1691 | static void | |
1692 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1693 | struct perf_event *event) |
8e1a2031 | 1694 | { |
161c85fa PZ |
1695 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1696 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1697 | |
161c85fa | 1698 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1699 | init_event_group(event); |
1700 | } | |
1701 | ||
1702 | /* | |
161c85fa | 1703 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1704 | */ |
1705 | static void | |
1706 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1707 | { | |
1708 | struct perf_event_groups *groups; | |
1709 | ||
1710 | groups = get_event_groups(event, ctx); | |
1711 | perf_event_groups_delete(groups, event); | |
1712 | } | |
1713 | ||
1714 | /* | |
95ed6c70 | 1715 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1716 | */ |
1717 | static struct perf_event * | |
95ed6c70 IR |
1718 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1719 | struct cgroup *cgrp) | |
8e1a2031 AB |
1720 | { |
1721 | struct perf_event *node_event = NULL, *match = NULL; | |
1722 | struct rb_node *node = groups->tree.rb_node; | |
95ed6c70 IR |
1723 | #ifdef CONFIG_CGROUP_PERF |
1724 | u64 node_cgrp_id, cgrp_id = 0; | |
1725 | ||
1726 | if (cgrp) | |
1727 | cgrp_id = cgrp->kn->id; | |
1728 | #endif | |
8e1a2031 AB |
1729 | |
1730 | while (node) { | |
161c85fa | 1731 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1732 | |
1733 | if (cpu < node_event->cpu) { | |
1734 | node = node->rb_left; | |
95ed6c70 IR |
1735 | continue; |
1736 | } | |
1737 | if (cpu > node_event->cpu) { | |
8e1a2031 | 1738 | node = node->rb_right; |
95ed6c70 IR |
1739 | continue; |
1740 | } | |
1741 | #ifdef CONFIG_CGROUP_PERF | |
1742 | node_cgrp_id = 0; | |
1743 | if (node_event->cgrp && node_event->cgrp->css.cgroup) | |
1744 | node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; | |
1745 | ||
1746 | if (cgrp_id < node_cgrp_id) { | |
8e1a2031 | 1747 | node = node->rb_left; |
95ed6c70 IR |
1748 | continue; |
1749 | } | |
1750 | if (cgrp_id > node_cgrp_id) { | |
1751 | node = node->rb_right; | |
1752 | continue; | |
8e1a2031 | 1753 | } |
95ed6c70 IR |
1754 | #endif |
1755 | match = node_event; | |
1756 | node = node->rb_left; | |
8e1a2031 AB |
1757 | } |
1758 | ||
1759 | return match; | |
1760 | } | |
1761 | ||
1cac7b1a PZ |
1762 | /* |
1763 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1764 | */ | |
1765 | static struct perf_event * | |
1766 | perf_event_groups_next(struct perf_event *event) | |
1767 | { | |
1768 | struct perf_event *next; | |
95ed6c70 IR |
1769 | #ifdef CONFIG_CGROUP_PERF |
1770 | u64 curr_cgrp_id = 0; | |
1771 | u64 next_cgrp_id = 0; | |
1772 | #endif | |
1cac7b1a PZ |
1773 | |
1774 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
95ed6c70 IR |
1775 | if (next == NULL || next->cpu != event->cpu) |
1776 | return NULL; | |
1777 | ||
1778 | #ifdef CONFIG_CGROUP_PERF | |
1779 | if (event->cgrp && event->cgrp->css.cgroup) | |
1780 | curr_cgrp_id = event->cgrp->css.cgroup->kn->id; | |
1cac7b1a | 1781 | |
95ed6c70 IR |
1782 | if (next->cgrp && next->cgrp->css.cgroup) |
1783 | next_cgrp_id = next->cgrp->css.cgroup->kn->id; | |
1784 | ||
1785 | if (curr_cgrp_id != next_cgrp_id) | |
1786 | return NULL; | |
1787 | #endif | |
1788 | return next; | |
1cac7b1a PZ |
1789 | } |
1790 | ||
8e1a2031 | 1791 | /* |
161c85fa | 1792 | * Iterate through the whole groups tree. |
8e1a2031 | 1793 | */ |
6e6804d2 PZ |
1794 | #define perf_event_groups_for_each(event, groups) \ |
1795 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1796 | typeof(*event), group_node); event; \ | |
1797 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1798 | typeof(*event), group_node)) | |
8e1a2031 | 1799 | |
fccc714b | 1800 | /* |
788faab7 | 1801 | * Add an event from the lists for its context. |
fccc714b PZ |
1802 | * Must be called with ctx->mutex and ctx->lock held. |
1803 | */ | |
04289bb9 | 1804 | static void |
cdd6c482 | 1805 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1806 | { |
c994d613 PZ |
1807 | lockdep_assert_held(&ctx->lock); |
1808 | ||
8a49542c PZ |
1809 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1810 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1811 | |
0d3d73aa PZ |
1812 | event->tstamp = perf_event_time(event); |
1813 | ||
04289bb9 | 1814 | /* |
8a49542c PZ |
1815 | * If we're a stand alone event or group leader, we go to the context |
1816 | * list, group events are kept attached to the group so that | |
1817 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1818 | */ |
8a49542c | 1819 | if (event->group_leader == event) { |
4ff6a8de | 1820 | event->group_caps = event->event_caps; |
8e1a2031 | 1821 | add_event_to_groups(event, ctx); |
5c148194 | 1822 | } |
592903cd | 1823 | |
cdd6c482 IM |
1824 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1825 | ctx->nr_events++; | |
1826 | if (event->attr.inherit_stat) | |
bfbd3381 | 1827 | ctx->nr_stat++; |
5a3126d4 | 1828 | |
33238c50 PZ |
1829 | if (event->state > PERF_EVENT_STATE_OFF) |
1830 | perf_cgroup_event_enable(event, ctx); | |
1831 | ||
5a3126d4 | 1832 | ctx->generation++; |
04289bb9 IM |
1833 | } |
1834 | ||
0231bb53 JO |
1835 | /* |
1836 | * Initialize event state based on the perf_event_attr::disabled. | |
1837 | */ | |
1838 | static inline void perf_event__state_init(struct perf_event *event) | |
1839 | { | |
1840 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1841 | PERF_EVENT_STATE_INACTIVE; | |
1842 | } | |
1843 | ||
a723968c | 1844 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1845 | { |
1846 | int entry = sizeof(u64); /* value */ | |
1847 | int size = 0; | |
1848 | int nr = 1; | |
1849 | ||
1850 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1851 | size += sizeof(u64); | |
1852 | ||
1853 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1854 | size += sizeof(u64); | |
1855 | ||
1856 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1857 | entry += sizeof(u64); | |
1858 | ||
1859 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1860 | nr += nr_siblings; |
c320c7b7 ACM |
1861 | size += sizeof(u64); |
1862 | } | |
1863 | ||
1864 | size += entry * nr; | |
1865 | event->read_size = size; | |
1866 | } | |
1867 | ||
a723968c | 1868 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1869 | { |
1870 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1871 | u16 size = 0; |
1872 | ||
c320c7b7 ACM |
1873 | if (sample_type & PERF_SAMPLE_IP) |
1874 | size += sizeof(data->ip); | |
1875 | ||
6844c09d ACM |
1876 | if (sample_type & PERF_SAMPLE_ADDR) |
1877 | size += sizeof(data->addr); | |
1878 | ||
1879 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1880 | size += sizeof(data->period); | |
1881 | ||
c3feedf2 AK |
1882 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1883 | size += sizeof(data->weight); | |
1884 | ||
6844c09d ACM |
1885 | if (sample_type & PERF_SAMPLE_READ) |
1886 | size += event->read_size; | |
1887 | ||
d6be9ad6 SE |
1888 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1889 | size += sizeof(data->data_src.val); | |
1890 | ||
fdfbbd07 AK |
1891 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1892 | size += sizeof(data->txn); | |
1893 | ||
fc7ce9c7 KL |
1894 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1895 | size += sizeof(data->phys_addr); | |
1896 | ||
6546b19f NK |
1897 | if (sample_type & PERF_SAMPLE_CGROUP) |
1898 | size += sizeof(data->cgroup); | |
1899 | ||
8d97e718 KL |
1900 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
1901 | size += sizeof(data->data_page_size); | |
1902 | ||
995f088e SE |
1903 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
1904 | size += sizeof(data->code_page_size); | |
1905 | ||
6844c09d ACM |
1906 | event->header_size = size; |
1907 | } | |
1908 | ||
a723968c PZ |
1909 | /* |
1910 | * Called at perf_event creation and when events are attached/detached from a | |
1911 | * group. | |
1912 | */ | |
1913 | static void perf_event__header_size(struct perf_event *event) | |
1914 | { | |
1915 | __perf_event_read_size(event, | |
1916 | event->group_leader->nr_siblings); | |
1917 | __perf_event_header_size(event, event->attr.sample_type); | |
1918 | } | |
1919 | ||
6844c09d ACM |
1920 | static void perf_event__id_header_size(struct perf_event *event) |
1921 | { | |
1922 | struct perf_sample_data *data; | |
1923 | u64 sample_type = event->attr.sample_type; | |
1924 | u16 size = 0; | |
1925 | ||
c320c7b7 ACM |
1926 | if (sample_type & PERF_SAMPLE_TID) |
1927 | size += sizeof(data->tid_entry); | |
1928 | ||
1929 | if (sample_type & PERF_SAMPLE_TIME) | |
1930 | size += sizeof(data->time); | |
1931 | ||
ff3d527c AH |
1932 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1933 | size += sizeof(data->id); | |
1934 | ||
c320c7b7 ACM |
1935 | if (sample_type & PERF_SAMPLE_ID) |
1936 | size += sizeof(data->id); | |
1937 | ||
1938 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1939 | size += sizeof(data->stream_id); | |
1940 | ||
1941 | if (sample_type & PERF_SAMPLE_CPU) | |
1942 | size += sizeof(data->cpu_entry); | |
1943 | ||
6844c09d | 1944 | event->id_header_size = size; |
c320c7b7 ACM |
1945 | } |
1946 | ||
a723968c PZ |
1947 | static bool perf_event_validate_size(struct perf_event *event) |
1948 | { | |
1949 | /* | |
1950 | * The values computed here will be over-written when we actually | |
1951 | * attach the event. | |
1952 | */ | |
1953 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1954 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1955 | perf_event__id_header_size(event); | |
1956 | ||
1957 | /* | |
1958 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1959 | * Conservative limit to allow for callchains and other variable fields. | |
1960 | */ | |
1961 | if (event->read_size + event->header_size + | |
1962 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1963 | return false; | |
1964 | ||
1965 | return true; | |
1966 | } | |
1967 | ||
8a49542c PZ |
1968 | static void perf_group_attach(struct perf_event *event) |
1969 | { | |
c320c7b7 | 1970 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1971 | |
a76a82a3 PZ |
1972 | lockdep_assert_held(&event->ctx->lock); |
1973 | ||
74c3337c PZ |
1974 | /* |
1975 | * We can have double attach due to group movement in perf_event_open. | |
1976 | */ | |
1977 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1978 | return; | |
1979 | ||
8a49542c PZ |
1980 | event->attach_state |= PERF_ATTACH_GROUP; |
1981 | ||
1982 | if (group_leader == event) | |
1983 | return; | |
1984 | ||
652884fe PZ |
1985 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1986 | ||
4ff6a8de | 1987 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1988 | |
8343aae6 | 1989 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1990 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1991 | |
1992 | perf_event__header_size(group_leader); | |
1993 | ||
edb39592 | 1994 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1995 | perf_event__header_size(pos); |
8a49542c PZ |
1996 | } |
1997 | ||
a63eaf34 | 1998 | /* |
788faab7 | 1999 | * Remove an event from the lists for its context. |
fccc714b | 2000 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 2001 | */ |
04289bb9 | 2002 | static void |
cdd6c482 | 2003 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 2004 | { |
652884fe PZ |
2005 | WARN_ON_ONCE(event->ctx != ctx); |
2006 | lockdep_assert_held(&ctx->lock); | |
2007 | ||
8a49542c PZ |
2008 | /* |
2009 | * We can have double detach due to exit/hot-unplug + close. | |
2010 | */ | |
2011 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 2012 | return; |
8a49542c PZ |
2013 | |
2014 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
2015 | ||
cdd6c482 IM |
2016 | ctx->nr_events--; |
2017 | if (event->attr.inherit_stat) | |
bfbd3381 | 2018 | ctx->nr_stat--; |
8bc20959 | 2019 | |
cdd6c482 | 2020 | list_del_rcu(&event->event_entry); |
04289bb9 | 2021 | |
8a49542c | 2022 | if (event->group_leader == event) |
8e1a2031 | 2023 | del_event_from_groups(event, ctx); |
5c148194 | 2024 | |
b2e74a26 SE |
2025 | /* |
2026 | * If event was in error state, then keep it | |
2027 | * that way, otherwise bogus counts will be | |
2028 | * returned on read(). The only way to get out | |
2029 | * of error state is by explicit re-enabling | |
2030 | * of the event | |
2031 | */ | |
33238c50 PZ |
2032 | if (event->state > PERF_EVENT_STATE_OFF) { |
2033 | perf_cgroup_event_disable(event, ctx); | |
0d3d73aa | 2034 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
33238c50 | 2035 | } |
5a3126d4 PZ |
2036 | |
2037 | ctx->generation++; | |
050735b0 PZ |
2038 | } |
2039 | ||
ab43762e AS |
2040 | static int |
2041 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2042 | { | |
2043 | if (!has_aux(aux_event)) | |
2044 | return 0; | |
2045 | ||
2046 | if (!event->pmu->aux_output_match) | |
2047 | return 0; | |
2048 | ||
2049 | return event->pmu->aux_output_match(aux_event); | |
2050 | } | |
2051 | ||
2052 | static void put_event(struct perf_event *event); | |
2053 | static void event_sched_out(struct perf_event *event, | |
2054 | struct perf_cpu_context *cpuctx, | |
2055 | struct perf_event_context *ctx); | |
2056 | ||
2057 | static void perf_put_aux_event(struct perf_event *event) | |
2058 | { | |
2059 | struct perf_event_context *ctx = event->ctx; | |
2060 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2061 | struct perf_event *iter; | |
2062 | ||
2063 | /* | |
2064 | * If event uses aux_event tear down the link | |
2065 | */ | |
2066 | if (event->aux_event) { | |
2067 | iter = event->aux_event; | |
2068 | event->aux_event = NULL; | |
2069 | put_event(iter); | |
2070 | return; | |
2071 | } | |
2072 | ||
2073 | /* | |
2074 | * If the event is an aux_event, tear down all links to | |
2075 | * it from other events. | |
2076 | */ | |
2077 | for_each_sibling_event(iter, event->group_leader) { | |
2078 | if (iter->aux_event != event) | |
2079 | continue; | |
2080 | ||
2081 | iter->aux_event = NULL; | |
2082 | put_event(event); | |
2083 | ||
2084 | /* | |
2085 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2086 | * state so that we don't try to schedule it again. Note | |
2087 | * that perf_event_enable() will clear the ERROR status. | |
2088 | */ | |
2089 | event_sched_out(iter, cpuctx, ctx); | |
2090 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2091 | } | |
2092 | } | |
2093 | ||
a4faf00d AS |
2094 | static bool perf_need_aux_event(struct perf_event *event) |
2095 | { | |
2096 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2097 | } | |
2098 | ||
ab43762e AS |
2099 | static int perf_get_aux_event(struct perf_event *event, |
2100 | struct perf_event *group_leader) | |
2101 | { | |
2102 | /* | |
2103 | * Our group leader must be an aux event if we want to be | |
2104 | * an aux_output. This way, the aux event will precede its | |
2105 | * aux_output events in the group, and therefore will always | |
2106 | * schedule first. | |
2107 | */ | |
2108 | if (!group_leader) | |
2109 | return 0; | |
2110 | ||
a4faf00d AS |
2111 | /* |
2112 | * aux_output and aux_sample_size are mutually exclusive. | |
2113 | */ | |
2114 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2115 | return 0; | |
2116 | ||
2117 | if (event->attr.aux_output && | |
2118 | !perf_aux_output_match(event, group_leader)) | |
2119 | return 0; | |
2120 | ||
2121 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2122 | return 0; |
2123 | ||
2124 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2125 | return 0; | |
2126 | ||
2127 | /* | |
2128 | * Link aux_outputs to their aux event; this is undone in | |
2129 | * perf_group_detach() by perf_put_aux_event(). When the | |
2130 | * group in torn down, the aux_output events loose their | |
2131 | * link to the aux_event and can't schedule any more. | |
2132 | */ | |
2133 | event->aux_event = group_leader; | |
2134 | ||
2135 | return 1; | |
2136 | } | |
2137 | ||
ab6f824c PZ |
2138 | static inline struct list_head *get_event_list(struct perf_event *event) |
2139 | { | |
2140 | struct perf_event_context *ctx = event->ctx; | |
2141 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2142 | } | |
2143 | ||
9f0c4fa1 KL |
2144 | /* |
2145 | * Events that have PERF_EV_CAP_SIBLING require being part of a group and | |
2146 | * cannot exist on their own, schedule them out and move them into the ERROR | |
2147 | * state. Also see _perf_event_enable(), it will not be able to recover | |
2148 | * this ERROR state. | |
2149 | */ | |
2150 | static inline void perf_remove_sibling_event(struct perf_event *event) | |
2151 | { | |
2152 | struct perf_event_context *ctx = event->ctx; | |
2153 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2154 | ||
2155 | event_sched_out(event, cpuctx, ctx); | |
2156 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2157 | } | |
2158 | ||
8a49542c | 2159 | static void perf_group_detach(struct perf_event *event) |
050735b0 | 2160 | { |
9f0c4fa1 | 2161 | struct perf_event *leader = event->group_leader; |
050735b0 | 2162 | struct perf_event *sibling, *tmp; |
6668128a | 2163 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2164 | |
6668128a | 2165 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2166 | |
8a49542c PZ |
2167 | /* |
2168 | * We can have double detach due to exit/hot-unplug + close. | |
2169 | */ | |
2170 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2171 | return; | |
2172 | ||
2173 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2174 | ||
ab43762e AS |
2175 | perf_put_aux_event(event); |
2176 | ||
8a49542c PZ |
2177 | /* |
2178 | * If this is a sibling, remove it from its group. | |
2179 | */ | |
9f0c4fa1 | 2180 | if (leader != event) { |
8343aae6 | 2181 | list_del_init(&event->sibling_list); |
8a49542c | 2182 | event->group_leader->nr_siblings--; |
c320c7b7 | 2183 | goto out; |
8a49542c PZ |
2184 | } |
2185 | ||
04289bb9 | 2186 | /* |
cdd6c482 IM |
2187 | * If this was a group event with sibling events then |
2188 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2189 | * to whatever list we are on. |
04289bb9 | 2190 | */ |
8343aae6 | 2191 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2192 | |
9f0c4fa1 KL |
2193 | if (sibling->event_caps & PERF_EV_CAP_SIBLING) |
2194 | perf_remove_sibling_event(sibling); | |
2195 | ||
04289bb9 | 2196 | sibling->group_leader = sibling; |
24868367 | 2197 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2198 | |
2199 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2200 | sibling->group_caps = event->group_caps; |
652884fe | 2201 | |
8e1a2031 | 2202 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2203 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2204 | |
ab6f824c PZ |
2205 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2206 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2207 | } |
2208 | ||
652884fe | 2209 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2210 | } |
c320c7b7 ACM |
2211 | |
2212 | out: | |
9f0c4fa1 | 2213 | for_each_sibling_event(tmp, leader) |
c320c7b7 | 2214 | perf_event__header_size(tmp); |
9f0c4fa1 KL |
2215 | |
2216 | perf_event__header_size(leader); | |
04289bb9 IM |
2217 | } |
2218 | ||
fadfe7be JO |
2219 | static bool is_orphaned_event(struct perf_event *event) |
2220 | { | |
a69b0ca4 | 2221 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2222 | } |
2223 | ||
2c81a647 | 2224 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2225 | { |
2226 | struct pmu *pmu = event->pmu; | |
2227 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2228 | } | |
2229 | ||
2c81a647 MR |
2230 | /* |
2231 | * Check whether we should attempt to schedule an event group based on | |
2232 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2233 | * potentially with a SW leader, so we must check all the filters, to | |
2234 | * determine whether a group is schedulable: | |
2235 | */ | |
2236 | static inline int pmu_filter_match(struct perf_event *event) | |
2237 | { | |
edb39592 | 2238 | struct perf_event *sibling; |
2c81a647 MR |
2239 | |
2240 | if (!__pmu_filter_match(event)) | |
2241 | return 0; | |
2242 | ||
edb39592 PZ |
2243 | for_each_sibling_event(sibling, event) { |
2244 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2245 | return 0; |
2246 | } | |
2247 | ||
2248 | return 1; | |
2249 | } | |
2250 | ||
fa66f07a SE |
2251 | static inline int |
2252 | event_filter_match(struct perf_event *event) | |
2253 | { | |
0b8f1e2e PZ |
2254 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2255 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2256 | } |
2257 | ||
9ffcfa6f SE |
2258 | static void |
2259 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2260 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2261 | struct perf_event_context *ctx) |
3b6f9e5c | 2262 | { |
0d3d73aa | 2263 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2264 | |
2265 | WARN_ON_ONCE(event->ctx != ctx); | |
2266 | lockdep_assert_held(&ctx->lock); | |
2267 | ||
cdd6c482 | 2268 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2269 | return; |
3b6f9e5c | 2270 | |
6668128a PZ |
2271 | /* |
2272 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2273 | * we can schedule events _OUT_ individually through things like | |
2274 | * __perf_remove_from_context(). | |
2275 | */ | |
2276 | list_del_init(&event->active_list); | |
2277 | ||
44377277 AS |
2278 | perf_pmu_disable(event->pmu); |
2279 | ||
28a967c3 PZ |
2280 | event->pmu->del(event, 0); |
2281 | event->oncpu = -1; | |
0d3d73aa | 2282 | |
1d54ad94 PZ |
2283 | if (READ_ONCE(event->pending_disable) >= 0) { |
2284 | WRITE_ONCE(event->pending_disable, -1); | |
33238c50 | 2285 | perf_cgroup_event_disable(event, ctx); |
0d3d73aa | 2286 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2287 | } |
0d3d73aa | 2288 | perf_event_set_state(event, state); |
3b6f9e5c | 2289 | |
cdd6c482 | 2290 | if (!is_software_event(event)) |
3b6f9e5c | 2291 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2292 | if (!--ctx->nr_active) |
2293 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2294 | if (event->attr.freq && event->attr.sample_freq) |
2295 | ctx->nr_freq--; | |
cdd6c482 | 2296 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2297 | cpuctx->exclusive = 0; |
44377277 AS |
2298 | |
2299 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2300 | } |
2301 | ||
d859e29f | 2302 | static void |
cdd6c482 | 2303 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2304 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2305 | struct perf_event_context *ctx) |
d859e29f | 2306 | { |
cdd6c482 | 2307 | struct perf_event *event; |
0d3d73aa PZ |
2308 | |
2309 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2310 | return; | |
d859e29f | 2311 | |
3f005e7d MR |
2312 | perf_pmu_disable(ctx->pmu); |
2313 | ||
cdd6c482 | 2314 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2315 | |
2316 | /* | |
2317 | * Schedule out siblings (if any): | |
2318 | */ | |
edb39592 | 2319 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2320 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2321 | |
3f005e7d | 2322 | perf_pmu_enable(ctx->pmu); |
d859e29f PM |
2323 | } |
2324 | ||
45a0e07a | 2325 | #define DETACH_GROUP 0x01UL |
0017960f | 2326 | |
0793a61d | 2327 | /* |
cdd6c482 | 2328 | * Cross CPU call to remove a performance event |
0793a61d | 2329 | * |
cdd6c482 | 2330 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2331 | * remove it from the context list. |
2332 | */ | |
fae3fde6 PZ |
2333 | static void |
2334 | __perf_remove_from_context(struct perf_event *event, | |
2335 | struct perf_cpu_context *cpuctx, | |
2336 | struct perf_event_context *ctx, | |
2337 | void *info) | |
0793a61d | 2338 | { |
45a0e07a | 2339 | unsigned long flags = (unsigned long)info; |
0793a61d | 2340 | |
3c5c8711 PZ |
2341 | if (ctx->is_active & EVENT_TIME) { |
2342 | update_context_time(ctx); | |
2343 | update_cgrp_time_from_cpuctx(cpuctx); | |
2344 | } | |
2345 | ||
cdd6c482 | 2346 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2347 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2348 | perf_group_detach(event); |
cdd6c482 | 2349 | list_del_event(event, ctx); |
39a43640 PZ |
2350 | |
2351 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2352 | ctx->is_active = 0; |
90c91dfb | 2353 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2354 | if (ctx->task) { |
2355 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2356 | cpuctx->task_ctx = NULL; | |
2357 | } | |
64ce3126 | 2358 | } |
0793a61d TG |
2359 | } |
2360 | ||
0793a61d | 2361 | /* |
cdd6c482 | 2362 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2363 | * |
cdd6c482 IM |
2364 | * If event->ctx is a cloned context, callers must make sure that |
2365 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2366 | * remains valid. This is OK when called from perf_release since |
2367 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2368 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2369 | * context has been detached from its task. |
0793a61d | 2370 | */ |
45a0e07a | 2371 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2372 | { |
a76a82a3 PZ |
2373 | struct perf_event_context *ctx = event->ctx; |
2374 | ||
2375 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2376 | |
45a0e07a | 2377 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2378 | |
2379 | /* | |
2380 | * The above event_function_call() can NO-OP when it hits | |
2381 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2382 | * from the context (by perf_event_exit_event()) but the grouping | |
2383 | * might still be in-tact. | |
2384 | */ | |
2385 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2386 | if ((flags & DETACH_GROUP) && | |
2387 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2388 | /* | |
2389 | * Since in that case we cannot possibly be scheduled, simply | |
2390 | * detach now. | |
2391 | */ | |
2392 | raw_spin_lock_irq(&ctx->lock); | |
2393 | perf_group_detach(event); | |
2394 | raw_spin_unlock_irq(&ctx->lock); | |
2395 | } | |
0793a61d TG |
2396 | } |
2397 | ||
d859e29f | 2398 | /* |
cdd6c482 | 2399 | * Cross CPU call to disable a performance event |
d859e29f | 2400 | */ |
fae3fde6 PZ |
2401 | static void __perf_event_disable(struct perf_event *event, |
2402 | struct perf_cpu_context *cpuctx, | |
2403 | struct perf_event_context *ctx, | |
2404 | void *info) | |
7b648018 | 2405 | { |
fae3fde6 PZ |
2406 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2407 | return; | |
7b648018 | 2408 | |
3c5c8711 PZ |
2409 | if (ctx->is_active & EVENT_TIME) { |
2410 | update_context_time(ctx); | |
2411 | update_cgrp_time_from_event(event); | |
2412 | } | |
2413 | ||
fae3fde6 PZ |
2414 | if (event == event->group_leader) |
2415 | group_sched_out(event, cpuctx, ctx); | |
2416 | else | |
2417 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2418 | |
2419 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
33238c50 | 2420 | perf_cgroup_event_disable(event, ctx); |
7b648018 PZ |
2421 | } |
2422 | ||
d859e29f | 2423 | /* |
788faab7 | 2424 | * Disable an event. |
c93f7669 | 2425 | * |
cdd6c482 IM |
2426 | * If event->ctx is a cloned context, callers must make sure that |
2427 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2428 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2429 | * perf_event_for_each_child or perf_event_for_each because they |
2430 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2431 | * goes to exit will block in perf_event_exit_event(). |
2432 | * | |
cdd6c482 | 2433 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2434 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2435 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2436 | */ |
f63a8daa | 2437 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2438 | { |
cdd6c482 | 2439 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2440 | |
e625cce1 | 2441 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2442 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2443 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2444 | return; |
53cfbf59 | 2445 | } |
e625cce1 | 2446 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2447 | |
fae3fde6 PZ |
2448 | event_function_call(event, __perf_event_disable, NULL); |
2449 | } | |
2450 | ||
2451 | void perf_event_disable_local(struct perf_event *event) | |
2452 | { | |
2453 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2454 | } |
f63a8daa PZ |
2455 | |
2456 | /* | |
2457 | * Strictly speaking kernel users cannot create groups and therefore this | |
2458 | * interface does not need the perf_event_ctx_lock() magic. | |
2459 | */ | |
2460 | void perf_event_disable(struct perf_event *event) | |
2461 | { | |
2462 | struct perf_event_context *ctx; | |
2463 | ||
2464 | ctx = perf_event_ctx_lock(event); | |
2465 | _perf_event_disable(event); | |
2466 | perf_event_ctx_unlock(event, ctx); | |
2467 | } | |
dcfce4a0 | 2468 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2469 | |
5aab90ce JO |
2470 | void perf_event_disable_inatomic(struct perf_event *event) |
2471 | { | |
1d54ad94 PZ |
2472 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2473 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2474 | irq_work_queue(&event->pending); |
2475 | } | |
2476 | ||
e5d1367f | 2477 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2478 | struct perf_event_context *ctx) |
e5d1367f SE |
2479 | { |
2480 | /* | |
2481 | * use the correct time source for the time snapshot | |
2482 | * | |
2483 | * We could get by without this by leveraging the | |
2484 | * fact that to get to this function, the caller | |
2485 | * has most likely already called update_context_time() | |
2486 | * and update_cgrp_time_xx() and thus both timestamp | |
2487 | * are identical (or very close). Given that tstamp is, | |
2488 | * already adjusted for cgroup, we could say that: | |
2489 | * tstamp - ctx->timestamp | |
2490 | * is equivalent to | |
2491 | * tstamp - cgrp->timestamp. | |
2492 | * | |
2493 | * Then, in perf_output_read(), the calculation would | |
2494 | * work with no changes because: | |
2495 | * - event is guaranteed scheduled in | |
2496 | * - no scheduled out in between | |
2497 | * - thus the timestamp would be the same | |
2498 | * | |
2499 | * But this is a bit hairy. | |
2500 | * | |
2501 | * So instead, we have an explicit cgroup call to remain | |
2502 | * within the time time source all along. We believe it | |
2503 | * is cleaner and simpler to understand. | |
2504 | */ | |
2505 | if (is_cgroup_event(event)) | |
0d3d73aa | 2506 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2507 | else |
0d3d73aa | 2508 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2509 | } |
2510 | ||
4fe757dd PZ |
2511 | #define MAX_INTERRUPTS (~0ULL) |
2512 | ||
2513 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2514 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2515 | |
235c7fc7 | 2516 | static int |
9ffcfa6f | 2517 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2518 | struct perf_cpu_context *cpuctx, |
6e37738a | 2519 | struct perf_event_context *ctx) |
235c7fc7 | 2520 | { |
44377277 | 2521 | int ret = 0; |
4158755d | 2522 | |
ab6f824c PZ |
2523 | WARN_ON_ONCE(event->ctx != ctx); |
2524 | ||
63342411 PZ |
2525 | lockdep_assert_held(&ctx->lock); |
2526 | ||
cdd6c482 | 2527 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2528 | return 0; |
2529 | ||
95ff4ca2 AS |
2530 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2531 | /* | |
0c1cbc18 PZ |
2532 | * Order event::oncpu write to happen before the ACTIVE state is |
2533 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2534 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2535 | */ |
2536 | smp_wmb(); | |
0d3d73aa | 2537 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2538 | |
2539 | /* | |
2540 | * Unthrottle events, since we scheduled we might have missed several | |
2541 | * ticks already, also for a heavily scheduling task there is little | |
2542 | * guarantee it'll get a tick in a timely manner. | |
2543 | */ | |
2544 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2545 | perf_log_throttle(event, 1); | |
2546 | event->hw.interrupts = 0; | |
2547 | } | |
2548 | ||
44377277 AS |
2549 | perf_pmu_disable(event->pmu); |
2550 | ||
0d3d73aa | 2551 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2552 | |
ec0d7729 AS |
2553 | perf_log_itrace_start(event); |
2554 | ||
a4eaf7f1 | 2555 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2556 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2557 | event->oncpu = -1; |
44377277 AS |
2558 | ret = -EAGAIN; |
2559 | goto out; | |
235c7fc7 IM |
2560 | } |
2561 | ||
cdd6c482 | 2562 | if (!is_software_event(event)) |
3b6f9e5c | 2563 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2564 | if (!ctx->nr_active++) |
2565 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2566 | if (event->attr.freq && event->attr.sample_freq) |
2567 | ctx->nr_freq++; | |
235c7fc7 | 2568 | |
cdd6c482 | 2569 | if (event->attr.exclusive) |
3b6f9e5c PM |
2570 | cpuctx->exclusive = 1; |
2571 | ||
44377277 AS |
2572 | out: |
2573 | perf_pmu_enable(event->pmu); | |
2574 | ||
2575 | return ret; | |
235c7fc7 IM |
2576 | } |
2577 | ||
6751b71e | 2578 | static int |
cdd6c482 | 2579 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2580 | struct perf_cpu_context *cpuctx, |
6e37738a | 2581 | struct perf_event_context *ctx) |
6751b71e | 2582 | { |
6bde9b6c | 2583 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2584 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2585 | |
cdd6c482 | 2586 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2587 | return 0; |
2588 | ||
fbbe0701 | 2589 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2590 | |
251ff2d4 PZ |
2591 | if (event_sched_in(group_event, cpuctx, ctx)) |
2592 | goto error; | |
6751b71e PM |
2593 | |
2594 | /* | |
2595 | * Schedule in siblings as one group (if any): | |
2596 | */ | |
edb39592 | 2597 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2598 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2599 | partial_group = event; |
6751b71e PM |
2600 | goto group_error; |
2601 | } | |
2602 | } | |
2603 | ||
9ffcfa6f | 2604 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2605 | return 0; |
9ffcfa6f | 2606 | |
6751b71e PM |
2607 | group_error: |
2608 | /* | |
2609 | * Groups can be scheduled in as one unit only, so undo any | |
2610 | * partial group before returning: | |
0d3d73aa | 2611 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2612 | */ |
edb39592 | 2613 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2614 | if (event == partial_group) |
0d3d73aa | 2615 | break; |
d7842da4 | 2616 | |
0d3d73aa | 2617 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2618 | } |
9ffcfa6f | 2619 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2620 | |
251ff2d4 | 2621 | error: |
ad5133b7 | 2622 | pmu->cancel_txn(pmu); |
6751b71e PM |
2623 | return -EAGAIN; |
2624 | } | |
2625 | ||
3b6f9e5c | 2626 | /* |
cdd6c482 | 2627 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2628 | */ |
cdd6c482 | 2629 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2630 | struct perf_cpu_context *cpuctx, |
2631 | int can_add_hw) | |
2632 | { | |
2633 | /* | |
cdd6c482 | 2634 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2635 | */ |
4ff6a8de | 2636 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2637 | return 1; |
2638 | /* | |
2639 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2640 | * events can go on. |
3b6f9e5c PM |
2641 | */ |
2642 | if (cpuctx->exclusive) | |
2643 | return 0; | |
2644 | /* | |
2645 | * If this group is exclusive and there are already | |
cdd6c482 | 2646 | * events on the CPU, it can't go on. |
3b6f9e5c | 2647 | */ |
1908dc91 | 2648 | if (event->attr.exclusive && !list_empty(get_event_list(event))) |
3b6f9e5c PM |
2649 | return 0; |
2650 | /* | |
2651 | * Otherwise, try to add it if all previous groups were able | |
2652 | * to go on. | |
2653 | */ | |
2654 | return can_add_hw; | |
2655 | } | |
2656 | ||
cdd6c482 IM |
2657 | static void add_event_to_ctx(struct perf_event *event, |
2658 | struct perf_event_context *ctx) | |
53cfbf59 | 2659 | { |
cdd6c482 | 2660 | list_add_event(event, ctx); |
8a49542c | 2661 | perf_group_attach(event); |
53cfbf59 PM |
2662 | } |
2663 | ||
bd2afa49 PZ |
2664 | static void ctx_sched_out(struct perf_event_context *ctx, |
2665 | struct perf_cpu_context *cpuctx, | |
2666 | enum event_type_t event_type); | |
2c29ef0f PZ |
2667 | static void |
2668 | ctx_sched_in(struct perf_event_context *ctx, | |
2669 | struct perf_cpu_context *cpuctx, | |
2670 | enum event_type_t event_type, | |
2671 | struct task_struct *task); | |
fe4b04fa | 2672 | |
bd2afa49 | 2673 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2674 | struct perf_event_context *ctx, |
2675 | enum event_type_t event_type) | |
bd2afa49 PZ |
2676 | { |
2677 | if (!cpuctx->task_ctx) | |
2678 | return; | |
2679 | ||
2680 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2681 | return; | |
2682 | ||
487f05e1 | 2683 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2684 | } |
2685 | ||
dce5855b PZ |
2686 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2687 | struct perf_event_context *ctx, | |
2688 | struct task_struct *task) | |
2689 | { | |
2690 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2691 | if (ctx) | |
2692 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2693 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2694 | if (ctx) | |
2695 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2696 | } | |
2697 | ||
487f05e1 AS |
2698 | /* |
2699 | * We want to maintain the following priority of scheduling: | |
2700 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2701 | * - task pinned (EVENT_PINNED) | |
2702 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2703 | * - task flexible (EVENT_FLEXIBLE). | |
2704 | * | |
2705 | * In order to avoid unscheduling and scheduling back in everything every | |
2706 | * time an event is added, only do it for the groups of equal priority and | |
2707 | * below. | |
2708 | * | |
2709 | * This can be called after a batch operation on task events, in which case | |
2710 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2711 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2712 | */ | |
3e349507 | 2713 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2714 | struct perf_event_context *task_ctx, |
2715 | enum event_type_t event_type) | |
0017960f | 2716 | { |
bd903afe | 2717 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2718 | bool cpu_event = !!(event_type & EVENT_CPU); |
2719 | ||
2720 | /* | |
2721 | * If pinned groups are involved, flexible groups also need to be | |
2722 | * scheduled out. | |
2723 | */ | |
2724 | if (event_type & EVENT_PINNED) | |
2725 | event_type |= EVENT_FLEXIBLE; | |
2726 | ||
bd903afe SL |
2727 | ctx_event_type = event_type & EVENT_ALL; |
2728 | ||
3e349507 PZ |
2729 | perf_pmu_disable(cpuctx->ctx.pmu); |
2730 | if (task_ctx) | |
487f05e1 AS |
2731 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2732 | ||
2733 | /* | |
2734 | * Decide which cpu ctx groups to schedule out based on the types | |
2735 | * of events that caused rescheduling: | |
2736 | * - EVENT_CPU: schedule out corresponding groups; | |
2737 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2738 | * - otherwise, do nothing more. | |
2739 | */ | |
2740 | if (cpu_event) | |
2741 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2742 | else if (ctx_event_type & EVENT_PINNED) | |
2743 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2744 | ||
3e349507 PZ |
2745 | perf_event_sched_in(cpuctx, task_ctx, current); |
2746 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2747 | } |
2748 | ||
c68d224e SE |
2749 | void perf_pmu_resched(struct pmu *pmu) |
2750 | { | |
2751 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2752 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2753 | ||
2754 | perf_ctx_lock(cpuctx, task_ctx); | |
2755 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2756 | perf_ctx_unlock(cpuctx, task_ctx); | |
2757 | } | |
2758 | ||
0793a61d | 2759 | /* |
cdd6c482 | 2760 | * Cross CPU call to install and enable a performance event |
682076ae | 2761 | * |
a096309b PZ |
2762 | * Very similar to remote_function() + event_function() but cannot assume that |
2763 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2764 | */ |
fe4b04fa | 2765 | static int __perf_install_in_context(void *info) |
0793a61d | 2766 | { |
a096309b PZ |
2767 | struct perf_event *event = info; |
2768 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2769 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2770 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2771 | bool reprogram = true; |
a096309b | 2772 | int ret = 0; |
0793a61d | 2773 | |
63b6da39 | 2774 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2775 | if (ctx->task) { |
b58f6b0d PZ |
2776 | raw_spin_lock(&ctx->lock); |
2777 | task_ctx = ctx; | |
a096309b | 2778 | |
63cae12b | 2779 | reprogram = (ctx->task == current); |
b58f6b0d | 2780 | |
39a43640 | 2781 | /* |
63cae12b PZ |
2782 | * If the task is running, it must be running on this CPU, |
2783 | * otherwise we cannot reprogram things. | |
2784 | * | |
2785 | * If its not running, we don't care, ctx->lock will | |
2786 | * serialize against it becoming runnable. | |
39a43640 | 2787 | */ |
63cae12b PZ |
2788 | if (task_curr(ctx->task) && !reprogram) { |
2789 | ret = -ESRCH; | |
2790 | goto unlock; | |
2791 | } | |
a096309b | 2792 | |
63cae12b | 2793 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2794 | } else if (task_ctx) { |
2795 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2796 | } |
b58f6b0d | 2797 | |
33801b94 | 2798 | #ifdef CONFIG_CGROUP_PERF |
33238c50 | 2799 | if (event->state > PERF_EVENT_STATE_OFF && is_cgroup_event(event)) { |
33801b94 | 2800 | /* |
2801 | * If the current cgroup doesn't match the event's | |
2802 | * cgroup, we should not try to schedule it. | |
2803 | */ | |
2804 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2805 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2806 | event->cgrp->css.cgroup); | |
2807 | } | |
2808 | #endif | |
2809 | ||
63cae12b | 2810 | if (reprogram) { |
a096309b PZ |
2811 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2812 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2813 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2814 | } else { |
2815 | add_event_to_ctx(event, ctx); | |
2816 | } | |
2817 | ||
63b6da39 | 2818 | unlock: |
2c29ef0f | 2819 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2820 | |
a096309b | 2821 | return ret; |
0793a61d TG |
2822 | } |
2823 | ||
8a58ddae AS |
2824 | static bool exclusive_event_installable(struct perf_event *event, |
2825 | struct perf_event_context *ctx); | |
2826 | ||
0793a61d | 2827 | /* |
a096309b PZ |
2828 | * Attach a performance event to a context. |
2829 | * | |
2830 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2831 | */ |
2832 | static void | |
cdd6c482 IM |
2833 | perf_install_in_context(struct perf_event_context *ctx, |
2834 | struct perf_event *event, | |
0793a61d TG |
2835 | int cpu) |
2836 | { | |
a096309b | 2837 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2838 | |
fe4b04fa PZ |
2839 | lockdep_assert_held(&ctx->mutex); |
2840 | ||
8a58ddae AS |
2841 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2842 | ||
0cda4c02 YZ |
2843 | if (event->cpu != -1) |
2844 | event->cpu = cpu; | |
c3f00c70 | 2845 | |
0b8f1e2e PZ |
2846 | /* |
2847 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2848 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2849 | */ | |
2850 | smp_store_release(&event->ctx, ctx); | |
2851 | ||
db0503e4 PZ |
2852 | /* |
2853 | * perf_event_attr::disabled events will not run and can be initialized | |
2854 | * without IPI. Except when this is the first event for the context, in | |
2855 | * that case we need the magic of the IPI to set ctx->is_active. | |
2856 | * | |
2857 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2858 | * event will issue the IPI and reprogram the hardware. | |
2859 | */ | |
2860 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2861 | raw_spin_lock_irq(&ctx->lock); | |
2862 | if (ctx->task == TASK_TOMBSTONE) { | |
2863 | raw_spin_unlock_irq(&ctx->lock); | |
2864 | return; | |
2865 | } | |
2866 | add_event_to_ctx(event, ctx); | |
2867 | raw_spin_unlock_irq(&ctx->lock); | |
2868 | return; | |
2869 | } | |
2870 | ||
a096309b PZ |
2871 | if (!task) { |
2872 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2873 | return; | |
2874 | } | |
2875 | ||
2876 | /* | |
2877 | * Should not happen, we validate the ctx is still alive before calling. | |
2878 | */ | |
2879 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2880 | return; | |
2881 | ||
39a43640 PZ |
2882 | /* |
2883 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2884 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2885 | * |
2886 | * Instead we use task_curr(), which tells us if the task is running. | |
2887 | * However, since we use task_curr() outside of rq::lock, we can race | |
2888 | * against the actual state. This means the result can be wrong. | |
2889 | * | |
2890 | * If we get a false positive, we retry, this is harmless. | |
2891 | * | |
2892 | * If we get a false negative, things are complicated. If we are after | |
2893 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2894 | * value must be correct. If we're before, it doesn't matter since | |
2895 | * perf_event_context_sched_in() will program the counter. | |
2896 | * | |
2897 | * However, this hinges on the remote context switch having observed | |
2898 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2899 | * ctx::lock in perf_event_context_sched_in(). | |
2900 | * | |
2901 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2902 | * we know any future context switch of task must see the | |
2903 | * perf_event_ctpx[] store. | |
39a43640 | 2904 | */ |
63cae12b | 2905 | |
63b6da39 | 2906 | /* |
63cae12b PZ |
2907 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2908 | * task_cpu() load, such that if the IPI then does not find the task | |
2909 | * running, a future context switch of that task must observe the | |
2910 | * store. | |
63b6da39 | 2911 | */ |
63cae12b PZ |
2912 | smp_mb(); |
2913 | again: | |
2914 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2915 | return; |
2916 | ||
2917 | raw_spin_lock_irq(&ctx->lock); | |
2918 | task = ctx->task; | |
84c4e620 | 2919 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2920 | /* |
2921 | * Cannot happen because we already checked above (which also | |
2922 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2923 | * against perf_event_exit_task_context(). | |
2924 | */ | |
63b6da39 PZ |
2925 | raw_spin_unlock_irq(&ctx->lock); |
2926 | return; | |
2927 | } | |
39a43640 | 2928 | /* |
63cae12b PZ |
2929 | * If the task is not running, ctx->lock will avoid it becoming so, |
2930 | * thus we can safely install the event. | |
39a43640 | 2931 | */ |
63cae12b PZ |
2932 | if (task_curr(task)) { |
2933 | raw_spin_unlock_irq(&ctx->lock); | |
2934 | goto again; | |
2935 | } | |
2936 | add_event_to_ctx(event, ctx); | |
2937 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2938 | } |
2939 | ||
d859e29f | 2940 | /* |
cdd6c482 | 2941 | * Cross CPU call to enable a performance event |
d859e29f | 2942 | */ |
fae3fde6 PZ |
2943 | static void __perf_event_enable(struct perf_event *event, |
2944 | struct perf_cpu_context *cpuctx, | |
2945 | struct perf_event_context *ctx, | |
2946 | void *info) | |
04289bb9 | 2947 | { |
cdd6c482 | 2948 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2949 | struct perf_event_context *task_ctx; |
04289bb9 | 2950 | |
6e801e01 PZ |
2951 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2952 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2953 | return; |
3cbed429 | 2954 | |
bd2afa49 PZ |
2955 | if (ctx->is_active) |
2956 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2957 | ||
0d3d73aa | 2958 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
33238c50 | 2959 | perf_cgroup_event_enable(event, ctx); |
04289bb9 | 2960 | |
fae3fde6 PZ |
2961 | if (!ctx->is_active) |
2962 | return; | |
2963 | ||
e5d1367f | 2964 | if (!event_filter_match(event)) { |
bd2afa49 | 2965 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2966 | return; |
e5d1367f | 2967 | } |
f4c4176f | 2968 | |
04289bb9 | 2969 | /* |
cdd6c482 | 2970 | * If the event is in a group and isn't the group leader, |
d859e29f | 2971 | * then don't put it on unless the group is on. |
04289bb9 | 2972 | */ |
bd2afa49 PZ |
2973 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2974 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2975 | return; |
bd2afa49 | 2976 | } |
fe4b04fa | 2977 | |
fae3fde6 PZ |
2978 | task_ctx = cpuctx->task_ctx; |
2979 | if (ctx->task) | |
2980 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2981 | |
487f05e1 | 2982 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2983 | } |
2984 | ||
d859e29f | 2985 | /* |
788faab7 | 2986 | * Enable an event. |
c93f7669 | 2987 | * |
cdd6c482 IM |
2988 | * If event->ctx is a cloned context, callers must make sure that |
2989 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2990 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2991 | * perf_event_for_each_child or perf_event_for_each as described |
2992 | * for perf_event_disable. | |
d859e29f | 2993 | */ |
f63a8daa | 2994 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2995 | { |
cdd6c482 | 2996 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2997 | |
7b648018 | 2998 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2999 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
3000 | event->state < PERF_EVENT_STATE_ERROR) { | |
9f0c4fa1 | 3001 | out: |
7b648018 | 3002 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
3003 | return; |
3004 | } | |
3005 | ||
d859e29f | 3006 | /* |
cdd6c482 | 3007 | * If the event is in error state, clear that first. |
7b648018 PZ |
3008 | * |
3009 | * That way, if we see the event in error state below, we know that it | |
3010 | * has gone back into error state, as distinct from the task having | |
3011 | * been scheduled away before the cross-call arrived. | |
d859e29f | 3012 | */ |
9f0c4fa1 KL |
3013 | if (event->state == PERF_EVENT_STATE_ERROR) { |
3014 | /* | |
3015 | * Detached SIBLING events cannot leave ERROR state. | |
3016 | */ | |
3017 | if (event->event_caps & PERF_EV_CAP_SIBLING && | |
3018 | event->group_leader == event) | |
3019 | goto out; | |
3020 | ||
cdd6c482 | 3021 | event->state = PERF_EVENT_STATE_OFF; |
9f0c4fa1 | 3022 | } |
e625cce1 | 3023 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 3024 | |
fae3fde6 | 3025 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 3026 | } |
f63a8daa PZ |
3027 | |
3028 | /* | |
3029 | * See perf_event_disable(); | |
3030 | */ | |
3031 | void perf_event_enable(struct perf_event *event) | |
3032 | { | |
3033 | struct perf_event_context *ctx; | |
3034 | ||
3035 | ctx = perf_event_ctx_lock(event); | |
3036 | _perf_event_enable(event); | |
3037 | perf_event_ctx_unlock(event, ctx); | |
3038 | } | |
dcfce4a0 | 3039 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 3040 | |
375637bc AS |
3041 | struct stop_event_data { |
3042 | struct perf_event *event; | |
3043 | unsigned int restart; | |
3044 | }; | |
3045 | ||
95ff4ca2 AS |
3046 | static int __perf_event_stop(void *info) |
3047 | { | |
375637bc AS |
3048 | struct stop_event_data *sd = info; |
3049 | struct perf_event *event = sd->event; | |
95ff4ca2 | 3050 | |
375637bc | 3051 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
3052 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
3053 | return 0; | |
3054 | ||
3055 | /* matches smp_wmb() in event_sched_in() */ | |
3056 | smp_rmb(); | |
3057 | ||
3058 | /* | |
3059 | * There is a window with interrupts enabled before we get here, | |
3060 | * so we need to check again lest we try to stop another CPU's event. | |
3061 | */ | |
3062 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3063 | return -EAGAIN; | |
3064 | ||
3065 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3066 | ||
375637bc AS |
3067 | /* |
3068 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3069 | * but it is only used for events with AUX ring buffer, and such | |
3070 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3071 | * see comments in perf_aux_output_begin(). | |
3072 | * | |
788faab7 | 3073 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3074 | * while restarting. |
3075 | */ | |
3076 | if (sd->restart) | |
c9bbdd48 | 3077 | event->pmu->start(event, 0); |
375637bc | 3078 | |
95ff4ca2 AS |
3079 | return 0; |
3080 | } | |
3081 | ||
767ae086 | 3082 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3083 | { |
3084 | struct stop_event_data sd = { | |
3085 | .event = event, | |
767ae086 | 3086 | .restart = restart, |
375637bc AS |
3087 | }; |
3088 | int ret = 0; | |
3089 | ||
3090 | do { | |
3091 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3092 | return 0; | |
3093 | ||
3094 | /* matches smp_wmb() in event_sched_in() */ | |
3095 | smp_rmb(); | |
3096 | ||
3097 | /* | |
3098 | * We only want to restart ACTIVE events, so if the event goes | |
3099 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3100 | * fall through with ret==-ENXIO. | |
3101 | */ | |
3102 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3103 | __perf_event_stop, &sd); | |
3104 | } while (ret == -EAGAIN); | |
3105 | ||
3106 | return ret; | |
3107 | } | |
3108 | ||
3109 | /* | |
3110 | * In order to contain the amount of racy and tricky in the address filter | |
3111 | * configuration management, it is a two part process: | |
3112 | * | |
3113 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3114 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3115 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3116 | * (p2) when an event is scheduled in (pmu::add), it calls |
3117 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3118 | * if the generation has changed since the previous call. | |
3119 | * | |
3120 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3121 | * | |
3122 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3123 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3124 | * ioctl; | |
3125 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
c1e8d7c6 | 3126 | * registered mapping, called for every new mmap(), with mm::mmap_lock down |
375637bc AS |
3127 | * for reading; |
3128 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3129 | * of exec. | |
3130 | */ | |
3131 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3132 | { | |
3133 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3134 | ||
3135 | if (!has_addr_filter(event)) | |
3136 | return; | |
3137 | ||
3138 | raw_spin_lock(&ifh->lock); | |
3139 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3140 | event->pmu->addr_filters_sync(event); | |
3141 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3142 | } | |
3143 | raw_spin_unlock(&ifh->lock); | |
3144 | } | |
3145 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3146 | ||
f63a8daa | 3147 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3148 | { |
2023b359 | 3149 | /* |
cdd6c482 | 3150 | * not supported on inherited events |
2023b359 | 3151 | */ |
2e939d1d | 3152 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3153 | return -EINVAL; |
3154 | ||
cdd6c482 | 3155 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3156 | _perf_event_enable(event); |
2023b359 PZ |
3157 | |
3158 | return 0; | |
79f14641 | 3159 | } |
f63a8daa PZ |
3160 | |
3161 | /* | |
3162 | * See perf_event_disable() | |
3163 | */ | |
3164 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3165 | { | |
3166 | struct perf_event_context *ctx; | |
3167 | int ret; | |
3168 | ||
3169 | ctx = perf_event_ctx_lock(event); | |
3170 | ret = _perf_event_refresh(event, refresh); | |
3171 | perf_event_ctx_unlock(event, ctx); | |
3172 | ||
3173 | return ret; | |
3174 | } | |
26ca5c11 | 3175 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3176 | |
32ff77e8 MC |
3177 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3178 | struct perf_event_attr *attr) | |
3179 | { | |
3180 | int err; | |
3181 | ||
3182 | _perf_event_disable(bp); | |
3183 | ||
3184 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3185 | |
bf06278c | 3186 | if (!bp->attr.disabled) |
32ff77e8 | 3187 | _perf_event_enable(bp); |
bf06278c JO |
3188 | |
3189 | return err; | |
32ff77e8 MC |
3190 | } |
3191 | ||
3192 | static int perf_event_modify_attr(struct perf_event *event, | |
3193 | struct perf_event_attr *attr) | |
3194 | { | |
3195 | if (event->attr.type != attr->type) | |
3196 | return -EINVAL; | |
3197 | ||
3198 | switch (event->attr.type) { | |
3199 | case PERF_TYPE_BREAKPOINT: | |
3200 | return perf_event_modify_breakpoint(event, attr); | |
3201 | default: | |
3202 | /* Place holder for future additions. */ | |
3203 | return -EOPNOTSUPP; | |
3204 | } | |
3205 | } | |
3206 | ||
5b0311e1 FW |
3207 | static void ctx_sched_out(struct perf_event_context *ctx, |
3208 | struct perf_cpu_context *cpuctx, | |
3209 | enum event_type_t event_type) | |
235c7fc7 | 3210 | { |
6668128a | 3211 | struct perf_event *event, *tmp; |
db24d33e | 3212 | int is_active = ctx->is_active; |
235c7fc7 | 3213 | |
c994d613 | 3214 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3215 | |
39a43640 PZ |
3216 | if (likely(!ctx->nr_events)) { |
3217 | /* | |
3218 | * See __perf_remove_from_context(). | |
3219 | */ | |
3220 | WARN_ON_ONCE(ctx->is_active); | |
3221 | if (ctx->task) | |
3222 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3223 | return; |
39a43640 PZ |
3224 | } |
3225 | ||
db24d33e | 3226 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3227 | if (!(ctx->is_active & EVENT_ALL)) |
3228 | ctx->is_active = 0; | |
3229 | ||
63e30d3e PZ |
3230 | if (ctx->task) { |
3231 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3232 | if (!ctx->is_active) | |
3233 | cpuctx->task_ctx = NULL; | |
3234 | } | |
facc4307 | 3235 | |
8fdc6539 PZ |
3236 | /* |
3237 | * Always update time if it was set; not only when it changes. | |
3238 | * Otherwise we can 'forget' to update time for any but the last | |
3239 | * context we sched out. For example: | |
3240 | * | |
3241 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3242 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3243 | * | |
3244 | * would only update time for the pinned events. | |
3245 | */ | |
3cbaa590 PZ |
3246 | if (is_active & EVENT_TIME) { |
3247 | /* update (and stop) ctx time */ | |
3248 | update_context_time(ctx); | |
3249 | update_cgrp_time_from_cpuctx(cpuctx); | |
3250 | } | |
3251 | ||
8fdc6539 PZ |
3252 | is_active ^= ctx->is_active; /* changed bits */ |
3253 | ||
3cbaa590 | 3254 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3255 | return; |
5b0311e1 | 3256 | |
075e0b00 | 3257 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3258 | if (is_active & EVENT_PINNED) { |
6668128a | 3259 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3260 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3261 | } |
889ff015 | 3262 | |
3cbaa590 | 3263 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3264 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3265 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3266 | |
3267 | /* | |
3268 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3269 | * rotate_necessary, is will be reset by | |
3270 | * ctx_flexible_sched_in() when needed. | |
3271 | */ | |
3272 | ctx->rotate_necessary = 0; | |
9ed6060d | 3273 | } |
1b9a644f | 3274 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3275 | } |
3276 | ||
564c2b21 | 3277 | /* |
5a3126d4 PZ |
3278 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3279 | * cloned from the same version of the same context. | |
3280 | * | |
3281 | * Equivalence is measured using a generation number in the context that is | |
3282 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3283 | * and list_del_event(). | |
564c2b21 | 3284 | */ |
cdd6c482 IM |
3285 | static int context_equiv(struct perf_event_context *ctx1, |
3286 | struct perf_event_context *ctx2) | |
564c2b21 | 3287 | { |
211de6eb PZ |
3288 | lockdep_assert_held(&ctx1->lock); |
3289 | lockdep_assert_held(&ctx2->lock); | |
3290 | ||
5a3126d4 PZ |
3291 | /* Pinning disables the swap optimization */ |
3292 | if (ctx1->pin_count || ctx2->pin_count) | |
3293 | return 0; | |
3294 | ||
3295 | /* If ctx1 is the parent of ctx2 */ | |
3296 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3297 | return 1; | |
3298 | ||
3299 | /* If ctx2 is the parent of ctx1 */ | |
3300 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3301 | return 1; | |
3302 | ||
3303 | /* | |
3304 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3305 | * hierarchy, see perf_event_init_context(). | |
3306 | */ | |
3307 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3308 | ctx1->parent_gen == ctx2->parent_gen) | |
3309 | return 1; | |
3310 | ||
3311 | /* Unmatched */ | |
3312 | return 0; | |
564c2b21 PM |
3313 | } |
3314 | ||
cdd6c482 IM |
3315 | static void __perf_event_sync_stat(struct perf_event *event, |
3316 | struct perf_event *next_event) | |
bfbd3381 PZ |
3317 | { |
3318 | u64 value; | |
3319 | ||
cdd6c482 | 3320 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3321 | return; |
3322 | ||
3323 | /* | |
cdd6c482 | 3324 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3325 | * because we're in the middle of a context switch and have IRQs |
3326 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3327 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3328 | * don't need to use it. |
3329 | */ | |
0d3d73aa | 3330 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3331 | event->pmu->read(event); |
bfbd3381 | 3332 | |
0d3d73aa | 3333 | perf_event_update_time(event); |
bfbd3381 PZ |
3334 | |
3335 | /* | |
cdd6c482 | 3336 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3337 | * values when we flip the contexts. |
3338 | */ | |
e7850595 PZ |
3339 | value = local64_read(&next_event->count); |
3340 | value = local64_xchg(&event->count, value); | |
3341 | local64_set(&next_event->count, value); | |
bfbd3381 | 3342 | |
cdd6c482 IM |
3343 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3344 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3345 | |
bfbd3381 | 3346 | /* |
19d2e755 | 3347 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3348 | */ |
cdd6c482 IM |
3349 | perf_event_update_userpage(event); |
3350 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3351 | } |
3352 | ||
cdd6c482 IM |
3353 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3354 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3355 | { |
cdd6c482 | 3356 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3357 | |
3358 | if (!ctx->nr_stat) | |
3359 | return; | |
3360 | ||
02ffdbc8 PZ |
3361 | update_context_time(ctx); |
3362 | ||
cdd6c482 IM |
3363 | event = list_first_entry(&ctx->event_list, |
3364 | struct perf_event, event_entry); | |
bfbd3381 | 3365 | |
cdd6c482 IM |
3366 | next_event = list_first_entry(&next_ctx->event_list, |
3367 | struct perf_event, event_entry); | |
bfbd3381 | 3368 | |
cdd6c482 IM |
3369 | while (&event->event_entry != &ctx->event_list && |
3370 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3371 | |
cdd6c482 | 3372 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3373 | |
cdd6c482 IM |
3374 | event = list_next_entry(event, event_entry); |
3375 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3376 | } |
3377 | } | |
3378 | ||
fe4b04fa PZ |
3379 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3380 | struct task_struct *next) | |
0793a61d | 3381 | { |
8dc85d54 | 3382 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3383 | struct perf_event_context *next_ctx; |
5a3126d4 | 3384 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3385 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3386 | int do_switch = 1; |
44fae179 | 3387 | struct pmu *pmu; |
0793a61d | 3388 | |
108b02cf PZ |
3389 | if (likely(!ctx)) |
3390 | return; | |
10989fb2 | 3391 | |
44fae179 | 3392 | pmu = ctx->pmu; |
108b02cf PZ |
3393 | cpuctx = __get_cpu_context(ctx); |
3394 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3395 | return; |
3396 | ||
c93f7669 | 3397 | rcu_read_lock(); |
8dc85d54 | 3398 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3399 | if (!next_ctx) |
3400 | goto unlock; | |
3401 | ||
3402 | parent = rcu_dereference(ctx->parent_ctx); | |
3403 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3404 | ||
3405 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3406 | if (!parent && !next_parent) |
5a3126d4 PZ |
3407 | goto unlock; |
3408 | ||
3409 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3410 | /* |
3411 | * Looks like the two contexts are clones, so we might be | |
3412 | * able to optimize the context switch. We lock both | |
3413 | * contexts and check that they are clones under the | |
3414 | * lock (including re-checking that neither has been | |
3415 | * uncloned in the meantime). It doesn't matter which | |
3416 | * order we take the locks because no other cpu could | |
3417 | * be trying to lock both of these tasks. | |
3418 | */ | |
e625cce1 TG |
3419 | raw_spin_lock(&ctx->lock); |
3420 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3421 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 | 3422 | |
63b6da39 PZ |
3423 | WRITE_ONCE(ctx->task, next); |
3424 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3425 | |
44fae179 KL |
3426 | perf_pmu_disable(pmu); |
3427 | ||
3428 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3429 | pmu->sched_task(ctx, false); | |
3430 | ||
c2b98a86 AB |
3431 | /* |
3432 | * PMU specific parts of task perf context can require | |
3433 | * additional synchronization. As an example of such | |
3434 | * synchronization see implementation details of Intel | |
3435 | * LBR call stack data profiling; | |
3436 | */ | |
3437 | if (pmu->swap_task_ctx) | |
3438 | pmu->swap_task_ctx(ctx, next_ctx); | |
3439 | else | |
3440 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3441 | |
44fae179 KL |
3442 | perf_pmu_enable(pmu); |
3443 | ||
63b6da39 PZ |
3444 | /* |
3445 | * RCU_INIT_POINTER here is safe because we've not | |
3446 | * modified the ctx and the above modification of | |
3447 | * ctx->task and ctx->task_ctx_data are immaterial | |
3448 | * since those values are always verified under | |
3449 | * ctx->lock which we're now holding. | |
3450 | */ | |
3451 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3452 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3453 | ||
c93f7669 | 3454 | do_switch = 0; |
bfbd3381 | 3455 | |
cdd6c482 | 3456 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3457 | } |
e625cce1 TG |
3458 | raw_spin_unlock(&next_ctx->lock); |
3459 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3460 | } |
5a3126d4 | 3461 | unlock: |
c93f7669 | 3462 | rcu_read_unlock(); |
564c2b21 | 3463 | |
c93f7669 | 3464 | if (do_switch) { |
facc4307 | 3465 | raw_spin_lock(&ctx->lock); |
44fae179 KL |
3466 | perf_pmu_disable(pmu); |
3467 | ||
3468 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3469 | pmu->sched_task(ctx, false); | |
487f05e1 | 3470 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
44fae179 KL |
3471 | |
3472 | perf_pmu_enable(pmu); | |
facc4307 | 3473 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3474 | } |
0793a61d TG |
3475 | } |
3476 | ||
ba532500 YZ |
3477 | void perf_sched_cb_dec(struct pmu *pmu) |
3478 | { | |
e48c1788 PZ |
3479 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3480 | ||
44fae179 | 3481 | --cpuctx->sched_cb_usage; |
ba532500 YZ |
3482 | } |
3483 | ||
e48c1788 | 3484 | |
ba532500 YZ |
3485 | void perf_sched_cb_inc(struct pmu *pmu) |
3486 | { | |
e48c1788 PZ |
3487 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3488 | ||
44fae179 | 3489 | cpuctx->sched_cb_usage++; |
ba532500 YZ |
3490 | } |
3491 | ||
3492 | /* | |
3493 | * This function provides the context switch callback to the lower code | |
3494 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3495 | * |
3496 | * This callback is relevant even to per-cpu events; for example multi event | |
3497 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3498 | * all queued PEBS records before we context switch to a new task. | |
ba532500 | 3499 | */ |
556cccad KL |
3500 | static void __perf_pmu_sched_task(struct perf_cpu_context *cpuctx, bool sched_in) |
3501 | { | |
3502 | struct pmu *pmu; | |
3503 | ||
3504 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ | |
3505 | ||
3506 | if (WARN_ON_ONCE(!pmu->sched_task)) | |
3507 | return; | |
3508 | ||
3509 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
3510 | perf_pmu_disable(pmu); | |
3511 | ||
3512 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
3513 | ||
3514 | perf_pmu_enable(pmu); | |
3515 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
3516 | } | |
3517 | ||
45ac1403 AH |
3518 | static void perf_event_switch(struct task_struct *task, |
3519 | struct task_struct *next_prev, bool sched_in); | |
3520 | ||
8dc85d54 PZ |
3521 | #define for_each_task_context_nr(ctxn) \ |
3522 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3523 | ||
3524 | /* | |
3525 | * Called from scheduler to remove the events of the current task, | |
3526 | * with interrupts disabled. | |
3527 | * | |
3528 | * We stop each event and update the event value in event->count. | |
3529 | * | |
3530 | * This does not protect us against NMI, but disable() | |
3531 | * sets the disabled bit in the control field of event _before_ | |
3532 | * accessing the event control register. If a NMI hits, then it will | |
3533 | * not restart the event. | |
3534 | */ | |
ab0cce56 JO |
3535 | void __perf_event_task_sched_out(struct task_struct *task, |
3536 | struct task_struct *next) | |
8dc85d54 PZ |
3537 | { |
3538 | int ctxn; | |
3539 | ||
45ac1403 AH |
3540 | if (atomic_read(&nr_switch_events)) |
3541 | perf_event_switch(task, next, false); | |
3542 | ||
8dc85d54 PZ |
3543 | for_each_task_context_nr(ctxn) |
3544 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3545 | |
3546 | /* | |
3547 | * if cgroup events exist on this CPU, then we need | |
3548 | * to check if we have to switch out PMU state. | |
3549 | * cgroup event are system-wide mode only | |
3550 | */ | |
4a32fea9 | 3551 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3552 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3553 | } |
3554 | ||
5b0311e1 FW |
3555 | /* |
3556 | * Called with IRQs disabled | |
3557 | */ | |
3558 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3559 | enum event_type_t event_type) | |
3560 | { | |
3561 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3562 | } |
3563 | ||
6eef8a71 | 3564 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3565 | { |
24fb6b8e IR |
3566 | const struct perf_event *le = *(const struct perf_event **)l; |
3567 | const struct perf_event *re = *(const struct perf_event **)r; | |
6eef8a71 IR |
3568 | |
3569 | return le->group_index < re->group_index; | |
3570 | } | |
3571 | ||
3572 | static void swap_ptr(void *l, void *r) | |
3573 | { | |
3574 | void **lp = l, **rp = r; | |
3575 | ||
3576 | swap(*lp, *rp); | |
3577 | } | |
3578 | ||
3579 | static const struct min_heap_callbacks perf_min_heap = { | |
3580 | .elem_size = sizeof(struct perf_event *), | |
3581 | .less = perf_less_group_idx, | |
3582 | .swp = swap_ptr, | |
3583 | }; | |
3584 | ||
3585 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3586 | { | |
3587 | struct perf_event **itrs = heap->data; | |
3588 | ||
3589 | if (event) { | |
3590 | itrs[heap->nr] = event; | |
3591 | heap->nr++; | |
3592 | } | |
3593 | } | |
3594 | ||
836196be IR |
3595 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3596 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3597 | int (*func)(struct perf_event *, void *), |
3598 | void *data) | |
3599 | { | |
95ed6c70 IR |
3600 | #ifdef CONFIG_CGROUP_PERF |
3601 | struct cgroup_subsys_state *css = NULL; | |
3602 | #endif | |
6eef8a71 IR |
3603 | /* Space for per CPU and/or any CPU event iterators. */ |
3604 | struct perf_event *itrs[2]; | |
836196be IR |
3605 | struct min_heap event_heap; |
3606 | struct perf_event **evt; | |
1cac7b1a | 3607 | int ret; |
8e1a2031 | 3608 | |
836196be IR |
3609 | if (cpuctx) { |
3610 | event_heap = (struct min_heap){ | |
3611 | .data = cpuctx->heap, | |
3612 | .nr = 0, | |
3613 | .size = cpuctx->heap_size, | |
3614 | }; | |
c2283c93 IR |
3615 | |
3616 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3617 | |
3618 | #ifdef CONFIG_CGROUP_PERF | |
3619 | if (cpuctx->cgrp) | |
3620 | css = &cpuctx->cgrp->css; | |
3621 | #endif | |
836196be IR |
3622 | } else { |
3623 | event_heap = (struct min_heap){ | |
3624 | .data = itrs, | |
3625 | .nr = 0, | |
3626 | .size = ARRAY_SIZE(itrs), | |
3627 | }; | |
3628 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3629 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3630 | } |
3631 | evt = event_heap.data; | |
3632 | ||
95ed6c70 IR |
3633 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3634 | ||
3635 | #ifdef CONFIG_CGROUP_PERF | |
3636 | for (; css; css = css->parent) | |
3637 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3638 | #endif | |
1cac7b1a | 3639 | |
6eef8a71 | 3640 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3641 | |
6eef8a71 | 3642 | while (event_heap.nr) { |
1cac7b1a PZ |
3643 | ret = func(*evt, data); |
3644 | if (ret) | |
3645 | return ret; | |
3646 | ||
3647 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3648 | if (*evt) |
3649 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3650 | else | |
3651 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3652 | } |
0793a61d | 3653 | |
1cac7b1a PZ |
3654 | return 0; |
3655 | } | |
3656 | ||
ab6f824c | 3657 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3658 | { |
2c2366c7 PZ |
3659 | struct perf_event_context *ctx = event->ctx; |
3660 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3661 | int *can_add_hw = data; | |
ab6f824c | 3662 | |
1cac7b1a PZ |
3663 | if (event->state <= PERF_EVENT_STATE_OFF) |
3664 | return 0; | |
3665 | ||
3666 | if (!event_filter_match(event)) | |
3667 | return 0; | |
3668 | ||
2c2366c7 PZ |
3669 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3670 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3671 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3672 | } |
1cac7b1a | 3673 | |
ab6f824c | 3674 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
33238c50 PZ |
3675 | if (event->attr.pinned) { |
3676 | perf_cgroup_event_disable(event, ctx); | |
ab6f824c | 3677 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); |
33238c50 | 3678 | } |
1cac7b1a | 3679 | |
2c2366c7 PZ |
3680 | *can_add_hw = 0; |
3681 | ctx->rotate_necessary = 1; | |
2714c396 | 3682 | perf_mux_hrtimer_restart(cpuctx); |
3b6f9e5c | 3683 | } |
1cac7b1a PZ |
3684 | |
3685 | return 0; | |
5b0311e1 FW |
3686 | } |
3687 | ||
3688 | static void | |
1cac7b1a PZ |
3689 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3690 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3691 | { |
2c2366c7 | 3692 | int can_add_hw = 1; |
3b6f9e5c | 3693 | |
836196be IR |
3694 | if (ctx != &cpuctx->ctx) |
3695 | cpuctx = NULL; | |
3696 | ||
3697 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3698 | smp_processor_id(), |
2c2366c7 | 3699 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3700 | } |
8e1a2031 | 3701 | |
1cac7b1a PZ |
3702 | static void |
3703 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3704 | struct perf_cpu_context *cpuctx) | |
3705 | { | |
2c2366c7 | 3706 | int can_add_hw = 1; |
0793a61d | 3707 | |
836196be IR |
3708 | if (ctx != &cpuctx->ctx) |
3709 | cpuctx = NULL; | |
3710 | ||
3711 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3712 | smp_processor_id(), |
2c2366c7 | 3713 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3714 | } |
3715 | ||
3716 | static void | |
3717 | ctx_sched_in(struct perf_event_context *ctx, | |
3718 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3719 | enum event_type_t event_type, |
3720 | struct task_struct *task) | |
5b0311e1 | 3721 | { |
db24d33e | 3722 | int is_active = ctx->is_active; |
c994d613 PZ |
3723 | u64 now; |
3724 | ||
3725 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3726 | |
5b0311e1 | 3727 | if (likely(!ctx->nr_events)) |
facc4307 | 3728 | return; |
5b0311e1 | 3729 | |
3cbaa590 | 3730 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3731 | if (ctx->task) { |
3732 | if (!is_active) | |
3733 | cpuctx->task_ctx = ctx; | |
3734 | else | |
3735 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3736 | } | |
3737 | ||
3cbaa590 PZ |
3738 | is_active ^= ctx->is_active; /* changed bits */ |
3739 | ||
3740 | if (is_active & EVENT_TIME) { | |
3741 | /* start ctx time */ | |
3742 | now = perf_clock(); | |
3743 | ctx->timestamp = now; | |
3744 | perf_cgroup_set_timestamp(task, ctx); | |
3745 | } | |
3746 | ||
5b0311e1 FW |
3747 | /* |
3748 | * First go through the list and put on any pinned groups | |
3749 | * in order to give them the best chance of going on. | |
3750 | */ | |
3cbaa590 | 3751 | if (is_active & EVENT_PINNED) |
6e37738a | 3752 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3753 | |
3754 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3755 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3756 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3757 | } |
3758 | ||
329c0e01 | 3759 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3760 | enum event_type_t event_type, |
3761 | struct task_struct *task) | |
329c0e01 FW |
3762 | { |
3763 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3764 | ||
e5d1367f | 3765 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3766 | } |
3767 | ||
e5d1367f SE |
3768 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3769 | struct task_struct *task) | |
235c7fc7 | 3770 | { |
108b02cf | 3771 | struct perf_cpu_context *cpuctx; |
556cccad | 3772 | struct pmu *pmu = ctx->pmu; |
235c7fc7 | 3773 | |
108b02cf | 3774 | cpuctx = __get_cpu_context(ctx); |
556cccad KL |
3775 | if (cpuctx->task_ctx == ctx) { |
3776 | if (cpuctx->sched_cb_usage) | |
3777 | __perf_pmu_sched_task(cpuctx, true); | |
329c0e01 | 3778 | return; |
556cccad | 3779 | } |
329c0e01 | 3780 | |
facc4307 | 3781 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3782 | /* |
3783 | * We must check ctx->nr_events while holding ctx->lock, such | |
3784 | * that we serialize against perf_install_in_context(). | |
3785 | */ | |
3786 | if (!ctx->nr_events) | |
3787 | goto unlock; | |
3788 | ||
556cccad | 3789 | perf_pmu_disable(pmu); |
329c0e01 FW |
3790 | /* |
3791 | * We want to keep the following priority order: | |
3792 | * cpu pinned (that don't need to move), task pinned, | |
3793 | * cpu flexible, task flexible. | |
fe45bafb AS |
3794 | * |
3795 | * However, if task's ctx is not carrying any pinned | |
3796 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3797 | */ |
8e1a2031 | 3798 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3799 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3800 | perf_event_sched_in(cpuctx, ctx, task); |
556cccad KL |
3801 | |
3802 | if (cpuctx->sched_cb_usage && pmu->sched_task) | |
3803 | pmu->sched_task(cpuctx->task_ctx, true); | |
3804 | ||
3805 | perf_pmu_enable(pmu); | |
fdccc3fb | 3806 | |
3807 | unlock: | |
facc4307 | 3808 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3809 | } |
3810 | ||
8dc85d54 PZ |
3811 | /* |
3812 | * Called from scheduler to add the events of the current task | |
3813 | * with interrupts disabled. | |
3814 | * | |
3815 | * We restore the event value and then enable it. | |
3816 | * | |
3817 | * This does not protect us against NMI, but enable() | |
3818 | * sets the enabled bit in the control field of event _before_ | |
3819 | * accessing the event control register. If a NMI hits, then it will | |
3820 | * keep the event running. | |
3821 | */ | |
ab0cce56 JO |
3822 | void __perf_event_task_sched_in(struct task_struct *prev, |
3823 | struct task_struct *task) | |
8dc85d54 PZ |
3824 | { |
3825 | struct perf_event_context *ctx; | |
3826 | int ctxn; | |
3827 | ||
7e41d177 PZ |
3828 | /* |
3829 | * If cgroup events exist on this CPU, then we need to check if we have | |
3830 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3831 | * | |
3832 | * Since cgroup events are CPU events, we must schedule these in before | |
3833 | * we schedule in the task events. | |
3834 | */ | |
3835 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3836 | perf_cgroup_sched_in(prev, task); | |
3837 | ||
8dc85d54 PZ |
3838 | for_each_task_context_nr(ctxn) { |
3839 | ctx = task->perf_event_ctxp[ctxn]; | |
3840 | if (likely(!ctx)) | |
3841 | continue; | |
3842 | ||
e5d1367f | 3843 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3844 | } |
d010b332 | 3845 | |
45ac1403 AH |
3846 | if (atomic_read(&nr_switch_events)) |
3847 | perf_event_switch(task, prev, true); | |
235c7fc7 IM |
3848 | } |
3849 | ||
abd50713 PZ |
3850 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3851 | { | |
3852 | u64 frequency = event->attr.sample_freq; | |
3853 | u64 sec = NSEC_PER_SEC; | |
3854 | u64 divisor, dividend; | |
3855 | ||
3856 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3857 | ||
3858 | count_fls = fls64(count); | |
3859 | nsec_fls = fls64(nsec); | |
3860 | frequency_fls = fls64(frequency); | |
3861 | sec_fls = 30; | |
3862 | ||
3863 | /* | |
3864 | * We got @count in @nsec, with a target of sample_freq HZ | |
3865 | * the target period becomes: | |
3866 | * | |
3867 | * @count * 10^9 | |
3868 | * period = ------------------- | |
3869 | * @nsec * sample_freq | |
3870 | * | |
3871 | */ | |
3872 | ||
3873 | /* | |
3874 | * Reduce accuracy by one bit such that @a and @b converge | |
3875 | * to a similar magnitude. | |
3876 | */ | |
fe4b04fa | 3877 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3878 | do { \ |
3879 | if (a##_fls > b##_fls) { \ | |
3880 | a >>= 1; \ | |
3881 | a##_fls--; \ | |
3882 | } else { \ | |
3883 | b >>= 1; \ | |
3884 | b##_fls--; \ | |
3885 | } \ | |
3886 | } while (0) | |
3887 | ||
3888 | /* | |
3889 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3890 | * the other, so that finally we can do a u64/u64 division. | |
3891 | */ | |
3892 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3893 | REDUCE_FLS(nsec, frequency); | |
3894 | REDUCE_FLS(sec, count); | |
3895 | } | |
3896 | ||
3897 | if (count_fls + sec_fls > 64) { | |
3898 | divisor = nsec * frequency; | |
3899 | ||
3900 | while (count_fls + sec_fls > 64) { | |
3901 | REDUCE_FLS(count, sec); | |
3902 | divisor >>= 1; | |
3903 | } | |
3904 | ||
3905 | dividend = count * sec; | |
3906 | } else { | |
3907 | dividend = count * sec; | |
3908 | ||
3909 | while (nsec_fls + frequency_fls > 64) { | |
3910 | REDUCE_FLS(nsec, frequency); | |
3911 | dividend >>= 1; | |
3912 | } | |
3913 | ||
3914 | divisor = nsec * frequency; | |
3915 | } | |
3916 | ||
f6ab91ad PZ |
3917 | if (!divisor) |
3918 | return dividend; | |
3919 | ||
abd50713 PZ |
3920 | return div64_u64(dividend, divisor); |
3921 | } | |
3922 | ||
e050e3f0 SE |
3923 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3924 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3925 | ||
f39d47ff | 3926 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3927 | { |
cdd6c482 | 3928 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3929 | s64 period, sample_period; |
bd2b5b12 PZ |
3930 | s64 delta; |
3931 | ||
abd50713 | 3932 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3933 | |
3934 | delta = (s64)(period - hwc->sample_period); | |
3935 | delta = (delta + 7) / 8; /* low pass filter */ | |
3936 | ||
3937 | sample_period = hwc->sample_period + delta; | |
3938 | ||
3939 | if (!sample_period) | |
3940 | sample_period = 1; | |
3941 | ||
bd2b5b12 | 3942 | hwc->sample_period = sample_period; |
abd50713 | 3943 | |
e7850595 | 3944 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3945 | if (disable) |
3946 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3947 | ||
e7850595 | 3948 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3949 | |
3950 | if (disable) | |
3951 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3952 | } |
bd2b5b12 PZ |
3953 | } |
3954 | ||
e050e3f0 SE |
3955 | /* |
3956 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3957 | * events. At the same time, make sure, having freq events does not change | |
3958 | * the rate of unthrottling as that would introduce bias. | |
3959 | */ | |
3960 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3961 | int needs_unthr) | |
60db5e09 | 3962 | { |
cdd6c482 IM |
3963 | struct perf_event *event; |
3964 | struct hw_perf_event *hwc; | |
e050e3f0 | 3965 | u64 now, period = TICK_NSEC; |
abd50713 | 3966 | s64 delta; |
60db5e09 | 3967 | |
e050e3f0 SE |
3968 | /* |
3969 | * only need to iterate over all events iff: | |
3970 | * - context have events in frequency mode (needs freq adjust) | |
3971 | * - there are events to unthrottle on this cpu | |
3972 | */ | |
3973 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3974 | return; |
3975 | ||
e050e3f0 | 3976 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3977 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3978 | |
03541f8b | 3979 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3980 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3981 | continue; |
3982 | ||
5632ab12 | 3983 | if (!event_filter_match(event)) |
5d27c23d PZ |
3984 | continue; |
3985 | ||
44377277 AS |
3986 | perf_pmu_disable(event->pmu); |
3987 | ||
cdd6c482 | 3988 | hwc = &event->hw; |
6a24ed6c | 3989 | |
ae23bff1 | 3990 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3991 | hwc->interrupts = 0; |
cdd6c482 | 3992 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3993 | event->pmu->start(event, 0); |
a78ac325 PZ |
3994 | } |
3995 | ||
cdd6c482 | 3996 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3997 | goto next; |
60db5e09 | 3998 | |
e050e3f0 SE |
3999 | /* |
4000 | * stop the event and update event->count | |
4001 | */ | |
4002 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4003 | ||
e7850595 | 4004 | now = local64_read(&event->count); |
abd50713 PZ |
4005 | delta = now - hwc->freq_count_stamp; |
4006 | hwc->freq_count_stamp = now; | |
60db5e09 | 4007 | |
e050e3f0 SE |
4008 | /* |
4009 | * restart the event | |
4010 | * reload only if value has changed | |
f39d47ff SE |
4011 | * we have stopped the event so tell that |
4012 | * to perf_adjust_period() to avoid stopping it | |
4013 | * twice. | |
e050e3f0 | 4014 | */ |
abd50713 | 4015 | if (delta > 0) |
f39d47ff | 4016 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
4017 | |
4018 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
4019 | next: |
4020 | perf_pmu_enable(event->pmu); | |
60db5e09 | 4021 | } |
e050e3f0 | 4022 | |
f39d47ff | 4023 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 4024 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
4025 | } |
4026 | ||
235c7fc7 | 4027 | /* |
8703a7cf | 4028 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 4029 | */ |
8703a7cf | 4030 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 4031 | { |
dddd3379 TG |
4032 | /* |
4033 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
4034 | * disabled by the inheritance code. | |
4035 | */ | |
8703a7cf PZ |
4036 | if (ctx->rotate_disable) |
4037 | return; | |
8e1a2031 | 4038 | |
8703a7cf PZ |
4039 | perf_event_groups_delete(&ctx->flexible_groups, event); |
4040 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
4041 | } |
4042 | ||
7fa343b7 | 4043 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 4044 | static inline struct perf_event * |
7fa343b7 | 4045 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 4046 | { |
7fa343b7 SL |
4047 | struct perf_event *event; |
4048 | ||
4049 | /* pick the first active flexible event */ | |
4050 | event = list_first_entry_or_null(&ctx->flexible_active, | |
4051 | struct perf_event, active_list); | |
4052 | ||
4053 | /* if no active flexible event, pick the first event */ | |
4054 | if (!event) { | |
4055 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
4056 | typeof(*event), group_node); | |
4057 | } | |
4058 | ||
90c91dfb PZ |
4059 | /* |
4060 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
4061 | * finds there are unschedulable events, it will set it again. | |
4062 | */ | |
4063 | ctx->rotate_necessary = 0; | |
4064 | ||
7fa343b7 | 4065 | return event; |
8d5bce0c PZ |
4066 | } |
4067 | ||
4068 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4069 | { | |
4070 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4071 | struct perf_event_context *task_ctx = NULL; |
4072 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4073 | |
4074 | /* | |
4075 | * Since we run this from IRQ context, nobody can install new | |
4076 | * events, thus the event count values are stable. | |
4077 | */ | |
7fc23a53 | 4078 | |
fd7d5517 IR |
4079 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4080 | task_ctx = cpuctx->task_ctx; | |
4081 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4082 | |
8d5bce0c PZ |
4083 | if (!(cpu_rotate || task_rotate)) |
4084 | return false; | |
0f5a2601 | 4085 | |
facc4307 | 4086 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4087 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4088 | |
8d5bce0c | 4089 | if (task_rotate) |
7fa343b7 | 4090 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4091 | if (cpu_rotate) |
7fa343b7 | 4092 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4093 | |
8d5bce0c PZ |
4094 | /* |
4095 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4096 | * and then, if needed CPU flexible. | |
4097 | */ | |
fd7d5517 IR |
4098 | if (task_event || (task_ctx && cpu_event)) |
4099 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4100 | if (cpu_event) |
4101 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4102 | |
8d5bce0c | 4103 | if (task_event) |
fd7d5517 | 4104 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4105 | if (cpu_event) |
4106 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4107 | |
fd7d5517 | 4108 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4109 | |
0f5a2601 PZ |
4110 | perf_pmu_enable(cpuctx->ctx.pmu); |
4111 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4112 | |
8d5bce0c | 4113 | return true; |
e9d2b064 PZ |
4114 | } |
4115 | ||
4116 | void perf_event_task_tick(void) | |
4117 | { | |
2fde4f94 MR |
4118 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4119 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4120 | int throttled; |
b5ab4cd5 | 4121 | |
16444645 | 4122 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4123 | |
e050e3f0 SE |
4124 | __this_cpu_inc(perf_throttled_seq); |
4125 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4126 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4127 | |
2fde4f94 | 4128 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4129 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4130 | } |
4131 | ||
889ff015 FW |
4132 | static int event_enable_on_exec(struct perf_event *event, |
4133 | struct perf_event_context *ctx) | |
4134 | { | |
4135 | if (!event->attr.enable_on_exec) | |
4136 | return 0; | |
4137 | ||
4138 | event->attr.enable_on_exec = 0; | |
4139 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4140 | return 0; | |
4141 | ||
0d3d73aa | 4142 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4143 | |
4144 | return 1; | |
4145 | } | |
4146 | ||
57e7986e | 4147 | /* |
cdd6c482 | 4148 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4149 | * This expects task == current. |
4150 | */ | |
c1274499 | 4151 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4152 | { |
c1274499 | 4153 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4154 | enum event_type_t event_type = 0; |
3e349507 | 4155 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4156 | struct perf_event *event; |
57e7986e PM |
4157 | unsigned long flags; |
4158 | int enabled = 0; | |
4159 | ||
4160 | local_irq_save(flags); | |
c1274499 | 4161 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4162 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4163 | goto out; |
4164 | ||
3e349507 PZ |
4165 | cpuctx = __get_cpu_context(ctx); |
4166 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4167 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4168 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4169 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4170 | event_type |= get_event_type(event); |
4171 | } | |
57e7986e PM |
4172 | |
4173 | /* | |
3e349507 | 4174 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4175 | */ |
3e349507 | 4176 | if (enabled) { |
211de6eb | 4177 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4178 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4179 | } else { |
4180 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4181 | } |
4182 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4183 | |
9ed6060d | 4184 | out: |
57e7986e | 4185 | local_irq_restore(flags); |
211de6eb PZ |
4186 | |
4187 | if (clone_ctx) | |
4188 | put_ctx(clone_ctx); | |
57e7986e PM |
4189 | } |
4190 | ||
0492d4c5 PZ |
4191 | struct perf_read_data { |
4192 | struct perf_event *event; | |
4193 | bool group; | |
7d88962e | 4194 | int ret; |
0492d4c5 PZ |
4195 | }; |
4196 | ||
451d24d1 | 4197 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4198 | { |
d6a2f903 DCC |
4199 | u16 local_pkg, event_pkg; |
4200 | ||
4201 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4202 | int local_cpu = smp_processor_id(); |
4203 | ||
4204 | event_pkg = topology_physical_package_id(event_cpu); | |
4205 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4206 | |
4207 | if (event_pkg == local_pkg) | |
4208 | return local_cpu; | |
4209 | } | |
4210 | ||
4211 | return event_cpu; | |
4212 | } | |
4213 | ||
0793a61d | 4214 | /* |
cdd6c482 | 4215 | * Cross CPU call to read the hardware event |
0793a61d | 4216 | */ |
cdd6c482 | 4217 | static void __perf_event_read(void *info) |
0793a61d | 4218 | { |
0492d4c5 PZ |
4219 | struct perf_read_data *data = info; |
4220 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4221 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4222 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4223 | struct pmu *pmu = event->pmu; |
621a01ea | 4224 | |
e1ac3614 PM |
4225 | /* |
4226 | * If this is a task context, we need to check whether it is | |
4227 | * the current task context of this cpu. If not it has been | |
4228 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4229 | * event->count would have been updated to a recent sample |
4230 | * when the event was scheduled out. | |
e1ac3614 PM |
4231 | */ |
4232 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4233 | return; | |
4234 | ||
e625cce1 | 4235 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4236 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4237 | update_context_time(ctx); |
e5d1367f SE |
4238 | update_cgrp_time_from_event(event); |
4239 | } | |
0492d4c5 | 4240 | |
0d3d73aa PZ |
4241 | perf_event_update_time(event); |
4242 | if (data->group) | |
4243 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4244 | |
4a00c16e SB |
4245 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4246 | goto unlock; | |
0492d4c5 | 4247 | |
4a00c16e SB |
4248 | if (!data->group) { |
4249 | pmu->read(event); | |
4250 | data->ret = 0; | |
0492d4c5 | 4251 | goto unlock; |
4a00c16e SB |
4252 | } |
4253 | ||
4254 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4255 | ||
4256 | pmu->read(event); | |
0492d4c5 | 4257 | |
edb39592 | 4258 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4259 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4260 | /* | |
4261 | * Use sibling's PMU rather than @event's since | |
4262 | * sibling could be on different (eg: software) PMU. | |
4263 | */ | |
0492d4c5 | 4264 | sub->pmu->read(sub); |
4a00c16e | 4265 | } |
0492d4c5 | 4266 | } |
4a00c16e SB |
4267 | |
4268 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4269 | |
4270 | unlock: | |
e625cce1 | 4271 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4272 | } |
4273 | ||
b5e58793 PZ |
4274 | static inline u64 perf_event_count(struct perf_event *event) |
4275 | { | |
c39a0e2c | 4276 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4277 | } |
4278 | ||
ffe8690c KX |
4279 | /* |
4280 | * NMI-safe method to read a local event, that is an event that | |
4281 | * is: | |
4282 | * - either for the current task, or for this CPU | |
4283 | * - does not have inherit set, for inherited task events | |
4284 | * will not be local and we cannot read them atomically | |
4285 | * - must not have a pmu::count method | |
4286 | */ | |
7d9285e8 YS |
4287 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4288 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4289 | { |
4290 | unsigned long flags; | |
f91840a3 | 4291 | int ret = 0; |
ffe8690c KX |
4292 | |
4293 | /* | |
4294 | * Disabling interrupts avoids all counter scheduling (context | |
4295 | * switches, timer based rotation and IPIs). | |
4296 | */ | |
4297 | local_irq_save(flags); | |
4298 | ||
ffe8690c KX |
4299 | /* |
4300 | * It must not be an event with inherit set, we cannot read | |
4301 | * all child counters from atomic context. | |
4302 | */ | |
f91840a3 AS |
4303 | if (event->attr.inherit) { |
4304 | ret = -EOPNOTSUPP; | |
4305 | goto out; | |
4306 | } | |
ffe8690c | 4307 | |
f91840a3 AS |
4308 | /* If this is a per-task event, it must be for current */ |
4309 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4310 | event->hw.target != current) { | |
4311 | ret = -EINVAL; | |
4312 | goto out; | |
4313 | } | |
4314 | ||
4315 | /* If this is a per-CPU event, it must be for this CPU */ | |
4316 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4317 | event->cpu != smp_processor_id()) { | |
4318 | ret = -EINVAL; | |
4319 | goto out; | |
4320 | } | |
ffe8690c | 4321 | |
befb1b3c RC |
4322 | /* If this is a pinned event it must be running on this CPU */ |
4323 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4324 | ret = -EBUSY; | |
4325 | goto out; | |
4326 | } | |
4327 | ||
ffe8690c KX |
4328 | /* |
4329 | * If the event is currently on this CPU, its either a per-task event, | |
4330 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4331 | * oncpu == -1). | |
4332 | */ | |
4333 | if (event->oncpu == smp_processor_id()) | |
4334 | event->pmu->read(event); | |
4335 | ||
f91840a3 | 4336 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4337 | if (enabled || running) { |
4338 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4339 | u64 __enabled, __running; | |
4340 | ||
4341 | __perf_update_times(event, now, &__enabled, &__running); | |
4342 | if (enabled) | |
4343 | *enabled = __enabled; | |
4344 | if (running) | |
4345 | *running = __running; | |
4346 | } | |
f91840a3 | 4347 | out: |
ffe8690c KX |
4348 | local_irq_restore(flags); |
4349 | ||
f91840a3 | 4350 | return ret; |
ffe8690c KX |
4351 | } |
4352 | ||
7d88962e | 4353 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4354 | { |
0c1cbc18 | 4355 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4356 | int event_cpu, ret = 0; |
7d88962e | 4357 | |
0793a61d | 4358 | /* |
cdd6c482 IM |
4359 | * If event is enabled and currently active on a CPU, update the |
4360 | * value in the event structure: | |
0793a61d | 4361 | */ |
0c1cbc18 PZ |
4362 | again: |
4363 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4364 | struct perf_read_data data; | |
4365 | ||
4366 | /* | |
4367 | * Orders the ->state and ->oncpu loads such that if we see | |
4368 | * ACTIVE we must also see the right ->oncpu. | |
4369 | * | |
4370 | * Matches the smp_wmb() from event_sched_in(). | |
4371 | */ | |
4372 | smp_rmb(); | |
d6a2f903 | 4373 | |
451d24d1 PZ |
4374 | event_cpu = READ_ONCE(event->oncpu); |
4375 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4376 | return 0; | |
4377 | ||
0c1cbc18 PZ |
4378 | data = (struct perf_read_data){ |
4379 | .event = event, | |
4380 | .group = group, | |
4381 | .ret = 0, | |
4382 | }; | |
4383 | ||
451d24d1 PZ |
4384 | preempt_disable(); |
4385 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4386 | |
58763148 PZ |
4387 | /* |
4388 | * Purposely ignore the smp_call_function_single() return | |
4389 | * value. | |
4390 | * | |
451d24d1 | 4391 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4392 | * scheduled out and that will have updated the event count. |
4393 | * | |
4394 | * Therefore, either way, we'll have an up-to-date event count | |
4395 | * after this. | |
4396 | */ | |
451d24d1 PZ |
4397 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4398 | preempt_enable(); | |
58763148 | 4399 | ret = data.ret; |
0c1cbc18 PZ |
4400 | |
4401 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4402 | struct perf_event_context *ctx = event->ctx; |
4403 | unsigned long flags; | |
4404 | ||
e625cce1 | 4405 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4406 | state = event->state; |
4407 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4408 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4409 | goto again; | |
4410 | } | |
4411 | ||
c530ccd9 | 4412 | /* |
0c1cbc18 PZ |
4413 | * May read while context is not active (e.g., thread is |
4414 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4415 | */ |
0c1cbc18 | 4416 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4417 | update_context_time(ctx); |
e5d1367f SE |
4418 | update_cgrp_time_from_event(event); |
4419 | } | |
0c1cbc18 | 4420 | |
0d3d73aa | 4421 | perf_event_update_time(event); |
0492d4c5 | 4422 | if (group) |
0d3d73aa | 4423 | perf_event_update_sibling_time(event); |
e625cce1 | 4424 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4425 | } |
7d88962e SB |
4426 | |
4427 | return ret; | |
0793a61d TG |
4428 | } |
4429 | ||
a63eaf34 | 4430 | /* |
cdd6c482 | 4431 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4432 | */ |
eb184479 | 4433 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4434 | { |
e625cce1 | 4435 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4436 | mutex_init(&ctx->mutex); |
2fde4f94 | 4437 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4438 | perf_event_groups_init(&ctx->pinned_groups); |
4439 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4440 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4441 | INIT_LIST_HEAD(&ctx->pinned_active); |
4442 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4443 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4444 | } |
4445 | ||
4446 | static struct perf_event_context * | |
4447 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4448 | { | |
4449 | struct perf_event_context *ctx; | |
4450 | ||
4451 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4452 | if (!ctx) | |
4453 | return NULL; | |
4454 | ||
4455 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4456 | if (task) |
4457 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4458 | ctx->pmu = pmu; |
4459 | ||
4460 | return ctx; | |
a63eaf34 PM |
4461 | } |
4462 | ||
2ebd4ffb MH |
4463 | static struct task_struct * |
4464 | find_lively_task_by_vpid(pid_t vpid) | |
4465 | { | |
4466 | struct task_struct *task; | |
0793a61d TG |
4467 | |
4468 | rcu_read_lock(); | |
2ebd4ffb | 4469 | if (!vpid) |
0793a61d TG |
4470 | task = current; |
4471 | else | |
2ebd4ffb | 4472 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4473 | if (task) |
4474 | get_task_struct(task); | |
4475 | rcu_read_unlock(); | |
4476 | ||
4477 | if (!task) | |
4478 | return ERR_PTR(-ESRCH); | |
4479 | ||
2ebd4ffb | 4480 | return task; |
2ebd4ffb MH |
4481 | } |
4482 | ||
fe4b04fa PZ |
4483 | /* |
4484 | * Returns a matching context with refcount and pincount. | |
4485 | */ | |
108b02cf | 4486 | static struct perf_event_context * |
4af57ef2 YZ |
4487 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4488 | struct perf_event *event) | |
0793a61d | 4489 | { |
211de6eb | 4490 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4491 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4492 | void *task_ctx_data = NULL; |
25346b93 | 4493 | unsigned long flags; |
8dc85d54 | 4494 | int ctxn, err; |
4af57ef2 | 4495 | int cpu = event->cpu; |
0793a61d | 4496 | |
22a4ec72 | 4497 | if (!task) { |
cdd6c482 | 4498 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4499 | err = perf_allow_cpu(&event->attr); |
4500 | if (err) | |
4501 | return ERR_PTR(err); | |
0793a61d | 4502 | |
108b02cf | 4503 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4504 | ctx = &cpuctx->ctx; |
c93f7669 | 4505 | get_ctx(ctx); |
fe4b04fa | 4506 | ++ctx->pin_count; |
0793a61d | 4507 | |
0793a61d TG |
4508 | return ctx; |
4509 | } | |
4510 | ||
8dc85d54 PZ |
4511 | err = -EINVAL; |
4512 | ctxn = pmu->task_ctx_nr; | |
4513 | if (ctxn < 0) | |
4514 | goto errout; | |
4515 | ||
4af57ef2 | 4516 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
ff9ff926 | 4517 | task_ctx_data = alloc_task_ctx_data(pmu); |
4af57ef2 YZ |
4518 | if (!task_ctx_data) { |
4519 | err = -ENOMEM; | |
4520 | goto errout; | |
4521 | } | |
4522 | } | |
4523 | ||
9ed6060d | 4524 | retry: |
8dc85d54 | 4525 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4526 | if (ctx) { |
211de6eb | 4527 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4528 | ++ctx->pin_count; |
4af57ef2 YZ |
4529 | |
4530 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4531 | ctx->task_ctx_data = task_ctx_data; | |
4532 | task_ctx_data = NULL; | |
4533 | } | |
e625cce1 | 4534 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4535 | |
4536 | if (clone_ctx) | |
4537 | put_ctx(clone_ctx); | |
9137fb28 | 4538 | } else { |
eb184479 | 4539 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4540 | err = -ENOMEM; |
4541 | if (!ctx) | |
4542 | goto errout; | |
eb184479 | 4543 | |
4af57ef2 YZ |
4544 | if (task_ctx_data) { |
4545 | ctx->task_ctx_data = task_ctx_data; | |
4546 | task_ctx_data = NULL; | |
4547 | } | |
4548 | ||
dbe08d82 ON |
4549 | err = 0; |
4550 | mutex_lock(&task->perf_event_mutex); | |
4551 | /* | |
4552 | * If it has already passed perf_event_exit_task(). | |
4553 | * we must see PF_EXITING, it takes this mutex too. | |
4554 | */ | |
4555 | if (task->flags & PF_EXITING) | |
4556 | err = -ESRCH; | |
4557 | else if (task->perf_event_ctxp[ctxn]) | |
4558 | err = -EAGAIN; | |
fe4b04fa | 4559 | else { |
9137fb28 | 4560 | get_ctx(ctx); |
fe4b04fa | 4561 | ++ctx->pin_count; |
dbe08d82 | 4562 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4563 | } |
dbe08d82 ON |
4564 | mutex_unlock(&task->perf_event_mutex); |
4565 | ||
4566 | if (unlikely(err)) { | |
9137fb28 | 4567 | put_ctx(ctx); |
dbe08d82 ON |
4568 | |
4569 | if (err == -EAGAIN) | |
4570 | goto retry; | |
4571 | goto errout; | |
a63eaf34 PM |
4572 | } |
4573 | } | |
4574 | ||
ff9ff926 | 4575 | free_task_ctx_data(pmu, task_ctx_data); |
0793a61d | 4576 | return ctx; |
c93f7669 | 4577 | |
9ed6060d | 4578 | errout: |
ff9ff926 | 4579 | free_task_ctx_data(pmu, task_ctx_data); |
c93f7669 | 4580 | return ERR_PTR(err); |
0793a61d TG |
4581 | } |
4582 | ||
6fb2915d | 4583 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4584 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4585 | |
cdd6c482 | 4586 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4587 | { |
cdd6c482 | 4588 | struct perf_event *event; |
592903cd | 4589 | |
cdd6c482 IM |
4590 | event = container_of(head, struct perf_event, rcu_head); |
4591 | if (event->ns) | |
4592 | put_pid_ns(event->ns); | |
6fb2915d | 4593 | perf_event_free_filter(event); |
cdd6c482 | 4594 | kfree(event); |
592903cd PZ |
4595 | } |
4596 | ||
b69cf536 | 4597 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4598 | struct perf_buffer *rb); |
925d519a | 4599 | |
f2fb6bef KL |
4600 | static void detach_sb_event(struct perf_event *event) |
4601 | { | |
4602 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4603 | ||
4604 | raw_spin_lock(&pel->lock); | |
4605 | list_del_rcu(&event->sb_list); | |
4606 | raw_spin_unlock(&pel->lock); | |
4607 | } | |
4608 | ||
a4f144eb | 4609 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4610 | { |
a4f144eb DCC |
4611 | struct perf_event_attr *attr = &event->attr; |
4612 | ||
f2fb6bef | 4613 | if (event->parent) |
a4f144eb | 4614 | return false; |
f2fb6bef KL |
4615 | |
4616 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4617 | return false; |
f2fb6bef | 4618 | |
a4f144eb DCC |
4619 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4620 | attr->comm || attr->comm_exec || | |
76193a94 | 4621 | attr->task || attr->ksymbol || |
e17d43b9 | 4622 | attr->context_switch || attr->text_poke || |
21038f2b | 4623 | attr->bpf_event) |
a4f144eb DCC |
4624 | return true; |
4625 | return false; | |
4626 | } | |
4627 | ||
4628 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4629 | { | |
4630 | if (is_sb_event(event)) | |
4631 | detach_sb_event(event); | |
f2fb6bef KL |
4632 | } |
4633 | ||
4beb31f3 | 4634 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4635 | { |
4beb31f3 FW |
4636 | if (event->parent) |
4637 | return; | |
4638 | ||
4beb31f3 FW |
4639 | if (is_cgroup_event(event)) |
4640 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4641 | } | |
925d519a | 4642 | |
555e0c1e FW |
4643 | #ifdef CONFIG_NO_HZ_FULL |
4644 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4645 | #endif | |
4646 | ||
4647 | static void unaccount_freq_event_nohz(void) | |
4648 | { | |
4649 | #ifdef CONFIG_NO_HZ_FULL | |
4650 | spin_lock(&nr_freq_lock); | |
4651 | if (atomic_dec_and_test(&nr_freq_events)) | |
4652 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4653 | spin_unlock(&nr_freq_lock); | |
4654 | #endif | |
4655 | } | |
4656 | ||
4657 | static void unaccount_freq_event(void) | |
4658 | { | |
4659 | if (tick_nohz_full_enabled()) | |
4660 | unaccount_freq_event_nohz(); | |
4661 | else | |
4662 | atomic_dec(&nr_freq_events); | |
4663 | } | |
4664 | ||
4beb31f3 FW |
4665 | static void unaccount_event(struct perf_event *event) |
4666 | { | |
25432ae9 PZ |
4667 | bool dec = false; |
4668 | ||
4beb31f3 FW |
4669 | if (event->parent) |
4670 | return; | |
4671 | ||
4672 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4673 | dec = true; |
4beb31f3 FW |
4674 | if (event->attr.mmap || event->attr.mmap_data) |
4675 | atomic_dec(&nr_mmap_events); | |
4676 | if (event->attr.comm) | |
4677 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4678 | if (event->attr.namespaces) |
4679 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4680 | if (event->attr.cgroup) |
4681 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4682 | if (event->attr.task) |
4683 | atomic_dec(&nr_task_events); | |
948b26b6 | 4684 | if (event->attr.freq) |
555e0c1e | 4685 | unaccount_freq_event(); |
45ac1403 | 4686 | if (event->attr.context_switch) { |
25432ae9 | 4687 | dec = true; |
45ac1403 AH |
4688 | atomic_dec(&nr_switch_events); |
4689 | } | |
4beb31f3 | 4690 | if (is_cgroup_event(event)) |
25432ae9 | 4691 | dec = true; |
4beb31f3 | 4692 | if (has_branch_stack(event)) |
25432ae9 | 4693 | dec = true; |
76193a94 SL |
4694 | if (event->attr.ksymbol) |
4695 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4696 | if (event->attr.bpf_event) |
4697 | atomic_dec(&nr_bpf_events); | |
e17d43b9 AH |
4698 | if (event->attr.text_poke) |
4699 | atomic_dec(&nr_text_poke_events); | |
25432ae9 | 4700 | |
9107c89e PZ |
4701 | if (dec) { |
4702 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4703 | schedule_delayed_work(&perf_sched_work, HZ); | |
4704 | } | |
4beb31f3 FW |
4705 | |
4706 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4707 | |
4708 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4709 | } |
925d519a | 4710 | |
9107c89e PZ |
4711 | static void perf_sched_delayed(struct work_struct *work) |
4712 | { | |
4713 | mutex_lock(&perf_sched_mutex); | |
4714 | if (atomic_dec_and_test(&perf_sched_count)) | |
4715 | static_branch_disable(&perf_sched_events); | |
4716 | mutex_unlock(&perf_sched_mutex); | |
4717 | } | |
4718 | ||
bed5b25a AS |
4719 | /* |
4720 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4721 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4722 | * at a time, so we disallow creating events that might conflict, namely: | |
4723 | * | |
4724 | * 1) cpu-wide events in the presence of per-task events, | |
4725 | * 2) per-task events in the presence of cpu-wide events, | |
4726 | * 3) two matching events on the same context. | |
4727 | * | |
4728 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4729 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4730 | */ |
4731 | static int exclusive_event_init(struct perf_event *event) | |
4732 | { | |
4733 | struct pmu *pmu = event->pmu; | |
4734 | ||
8a58ddae | 4735 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4736 | return 0; |
4737 | ||
4738 | /* | |
4739 | * Prevent co-existence of per-task and cpu-wide events on the | |
4740 | * same exclusive pmu. | |
4741 | * | |
4742 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4743 | * events on this "exclusive" pmu, positive means there are | |
4744 | * per-task events. | |
4745 | * | |
4746 | * Since this is called in perf_event_alloc() path, event::ctx | |
4747 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4748 | * to mean "per-task event", because unlike other attach states it | |
4749 | * never gets cleared. | |
4750 | */ | |
4751 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4752 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4753 | return -EBUSY; | |
4754 | } else { | |
4755 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4756 | return -EBUSY; | |
4757 | } | |
4758 | ||
4759 | return 0; | |
4760 | } | |
4761 | ||
4762 | static void exclusive_event_destroy(struct perf_event *event) | |
4763 | { | |
4764 | struct pmu *pmu = event->pmu; | |
4765 | ||
8a58ddae | 4766 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4767 | return; |
4768 | ||
4769 | /* see comment in exclusive_event_init() */ | |
4770 | if (event->attach_state & PERF_ATTACH_TASK) | |
4771 | atomic_dec(&pmu->exclusive_cnt); | |
4772 | else | |
4773 | atomic_inc(&pmu->exclusive_cnt); | |
4774 | } | |
4775 | ||
4776 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4777 | { | |
3bf6215a | 4778 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4779 | (e1->cpu == e2->cpu || |
4780 | e1->cpu == -1 || | |
4781 | e2->cpu == -1)) | |
4782 | return true; | |
4783 | return false; | |
4784 | } | |
4785 | ||
bed5b25a AS |
4786 | static bool exclusive_event_installable(struct perf_event *event, |
4787 | struct perf_event_context *ctx) | |
4788 | { | |
4789 | struct perf_event *iter_event; | |
4790 | struct pmu *pmu = event->pmu; | |
4791 | ||
8a58ddae AS |
4792 | lockdep_assert_held(&ctx->mutex); |
4793 | ||
4794 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4795 | return true; |
4796 | ||
4797 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4798 | if (exclusive_event_match(iter_event, event)) | |
4799 | return false; | |
4800 | } | |
4801 | ||
4802 | return true; | |
4803 | } | |
4804 | ||
375637bc AS |
4805 | static void perf_addr_filters_splice(struct perf_event *event, |
4806 | struct list_head *head); | |
4807 | ||
683ede43 | 4808 | static void _free_event(struct perf_event *event) |
f1600952 | 4809 | { |
e360adbe | 4810 | irq_work_sync(&event->pending); |
925d519a | 4811 | |
4beb31f3 | 4812 | unaccount_event(event); |
9ee318a7 | 4813 | |
da97e184 JFG |
4814 | security_perf_event_free(event); |
4815 | ||
76369139 | 4816 | if (event->rb) { |
9bb5d40c PZ |
4817 | /* |
4818 | * Can happen when we close an event with re-directed output. | |
4819 | * | |
4820 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4821 | * over us; possibly making our ring_buffer_put() the last. | |
4822 | */ | |
4823 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4824 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4825 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4826 | } |
4827 | ||
e5d1367f SE |
4828 | if (is_cgroup_event(event)) |
4829 | perf_detach_cgroup(event); | |
4830 | ||
a0733e69 PZ |
4831 | if (!event->parent) { |
4832 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4833 | put_callchain_buffers(); | |
4834 | } | |
4835 | ||
4836 | perf_event_free_bpf_prog(event); | |
375637bc | 4837 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4838 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4839 | |
4840 | if (event->destroy) | |
4841 | event->destroy(event); | |
4842 | ||
1cf8dfe8 PZ |
4843 | /* |
4844 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4845 | * hw.target. | |
4846 | */ | |
621b6d2e PB |
4847 | if (event->hw.target) |
4848 | put_task_struct(event->hw.target); | |
4849 | ||
1cf8dfe8 PZ |
4850 | /* |
4851 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4852 | * all task references must be cleaned up. | |
4853 | */ | |
4854 | if (event->ctx) | |
4855 | put_ctx(event->ctx); | |
4856 | ||
62a92c8f AS |
4857 | exclusive_event_destroy(event); |
4858 | module_put(event->pmu->module); | |
a0733e69 PZ |
4859 | |
4860 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4861 | } |
4862 | ||
683ede43 PZ |
4863 | /* |
4864 | * Used to free events which have a known refcount of 1, such as in error paths | |
4865 | * where the event isn't exposed yet and inherited events. | |
4866 | */ | |
4867 | static void free_event(struct perf_event *event) | |
0793a61d | 4868 | { |
683ede43 PZ |
4869 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4870 | "unexpected event refcount: %ld; ptr=%p\n", | |
4871 | atomic_long_read(&event->refcount), event)) { | |
4872 | /* leak to avoid use-after-free */ | |
4873 | return; | |
4874 | } | |
0793a61d | 4875 | |
683ede43 | 4876 | _free_event(event); |
0793a61d TG |
4877 | } |
4878 | ||
a66a3052 | 4879 | /* |
f8697762 | 4880 | * Remove user event from the owner task. |
a66a3052 | 4881 | */ |
f8697762 | 4882 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4883 | { |
8882135b | 4884 | struct task_struct *owner; |
fb0459d7 | 4885 | |
8882135b | 4886 | rcu_read_lock(); |
8882135b | 4887 | /* |
f47c02c0 PZ |
4888 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4889 | * observe !owner it means the list deletion is complete and we can | |
4890 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4891 | * owner->perf_event_mutex. |
4892 | */ | |
506458ef | 4893 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4894 | if (owner) { |
4895 | /* | |
4896 | * Since delayed_put_task_struct() also drops the last | |
4897 | * task reference we can safely take a new reference | |
4898 | * while holding the rcu_read_lock(). | |
4899 | */ | |
4900 | get_task_struct(owner); | |
4901 | } | |
4902 | rcu_read_unlock(); | |
4903 | ||
4904 | if (owner) { | |
f63a8daa PZ |
4905 | /* |
4906 | * If we're here through perf_event_exit_task() we're already | |
4907 | * holding ctx->mutex which would be an inversion wrt. the | |
4908 | * normal lock order. | |
4909 | * | |
4910 | * However we can safely take this lock because its the child | |
4911 | * ctx->mutex. | |
4912 | */ | |
4913 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4914 | ||
8882135b PZ |
4915 | /* |
4916 | * We have to re-check the event->owner field, if it is cleared | |
4917 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4918 | * ensured they're done, and we can proceed with freeing the | |
4919 | * event. | |
4920 | */ | |
f47c02c0 | 4921 | if (event->owner) { |
8882135b | 4922 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4923 | smp_store_release(&event->owner, NULL); |
4924 | } | |
8882135b PZ |
4925 | mutex_unlock(&owner->perf_event_mutex); |
4926 | put_task_struct(owner); | |
4927 | } | |
f8697762 JO |
4928 | } |
4929 | ||
f8697762 JO |
4930 | static void put_event(struct perf_event *event) |
4931 | { | |
f8697762 JO |
4932 | if (!atomic_long_dec_and_test(&event->refcount)) |
4933 | return; | |
4934 | ||
c6e5b732 PZ |
4935 | _free_event(event); |
4936 | } | |
4937 | ||
4938 | /* | |
4939 | * Kill an event dead; while event:refcount will preserve the event | |
4940 | * object, it will not preserve its functionality. Once the last 'user' | |
4941 | * gives up the object, we'll destroy the thing. | |
4942 | */ | |
4943 | int perf_event_release_kernel(struct perf_event *event) | |
4944 | { | |
a4f4bb6d | 4945 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4946 | struct perf_event *child, *tmp; |
82d94856 | 4947 | LIST_HEAD(free_list); |
c6e5b732 | 4948 | |
a4f4bb6d PZ |
4949 | /* |
4950 | * If we got here through err_file: fput(event_file); we will not have | |
4951 | * attached to a context yet. | |
4952 | */ | |
4953 | if (!ctx) { | |
4954 | WARN_ON_ONCE(event->attach_state & | |
4955 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4956 | goto no_ctx; | |
4957 | } | |
4958 | ||
f8697762 JO |
4959 | if (!is_kernel_event(event)) |
4960 | perf_remove_from_owner(event); | |
8882135b | 4961 | |
5fa7c8ec | 4962 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4963 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4964 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4965 | |
a69b0ca4 | 4966 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4967 | /* |
d8a8cfc7 | 4968 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4969 | * anymore. |
683ede43 | 4970 | * |
a69b0ca4 PZ |
4971 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4972 | * also see this, most importantly inherit_event() which will avoid | |
4973 | * placing more children on the list. | |
683ede43 | 4974 | * |
c6e5b732 PZ |
4975 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4976 | * child events. | |
683ede43 | 4977 | */ |
a69b0ca4 PZ |
4978 | event->state = PERF_EVENT_STATE_DEAD; |
4979 | raw_spin_unlock_irq(&ctx->lock); | |
4980 | ||
4981 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4982 | |
c6e5b732 PZ |
4983 | again: |
4984 | mutex_lock(&event->child_mutex); | |
4985 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4986 | |
c6e5b732 PZ |
4987 | /* |
4988 | * Cannot change, child events are not migrated, see the | |
4989 | * comment with perf_event_ctx_lock_nested(). | |
4990 | */ | |
506458ef | 4991 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4992 | /* |
4993 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4994 | * through hoops. We start by grabbing a reference on the ctx. | |
4995 | * | |
4996 | * Since the event cannot get freed while we hold the | |
4997 | * child_mutex, the context must also exist and have a !0 | |
4998 | * reference count. | |
4999 | */ | |
5000 | get_ctx(ctx); | |
5001 | ||
5002 | /* | |
5003 | * Now that we have a ctx ref, we can drop child_mutex, and | |
5004 | * acquire ctx::mutex without fear of it going away. Then we | |
5005 | * can re-acquire child_mutex. | |
5006 | */ | |
5007 | mutex_unlock(&event->child_mutex); | |
5008 | mutex_lock(&ctx->mutex); | |
5009 | mutex_lock(&event->child_mutex); | |
5010 | ||
5011 | /* | |
5012 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
5013 | * state, if child is still the first entry, it didn't get freed | |
5014 | * and we can continue doing so. | |
5015 | */ | |
5016 | tmp = list_first_entry_or_null(&event->child_list, | |
5017 | struct perf_event, child_list); | |
5018 | if (tmp == child) { | |
5019 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 5020 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
5021 | /* |
5022 | * This matches the refcount bump in inherit_event(); | |
5023 | * this can't be the last reference. | |
5024 | */ | |
5025 | put_event(event); | |
5026 | } | |
5027 | ||
5028 | mutex_unlock(&event->child_mutex); | |
5029 | mutex_unlock(&ctx->mutex); | |
5030 | put_ctx(ctx); | |
5031 | goto again; | |
5032 | } | |
5033 | mutex_unlock(&event->child_mutex); | |
5034 | ||
82d94856 | 5035 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
5036 | void *var = &child->ctx->refcount; |
5037 | ||
82d94856 PZ |
5038 | list_del(&child->child_list); |
5039 | free_event(child); | |
1cf8dfe8 PZ |
5040 | |
5041 | /* | |
5042 | * Wake any perf_event_free_task() waiting for this event to be | |
5043 | * freed. | |
5044 | */ | |
5045 | smp_mb(); /* pairs with wait_var_event() */ | |
5046 | wake_up_var(var); | |
82d94856 PZ |
5047 | } |
5048 | ||
a4f4bb6d PZ |
5049 | no_ctx: |
5050 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
5051 | return 0; |
5052 | } | |
5053 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
5054 | ||
8b10c5e2 PZ |
5055 | /* |
5056 | * Called when the last reference to the file is gone. | |
5057 | */ | |
a6fa941d AV |
5058 | static int perf_release(struct inode *inode, struct file *file) |
5059 | { | |
c6e5b732 | 5060 | perf_event_release_kernel(file->private_data); |
a6fa941d | 5061 | return 0; |
fb0459d7 | 5062 | } |
fb0459d7 | 5063 | |
ca0dd44c | 5064 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 5065 | { |
cdd6c482 | 5066 | struct perf_event *child; |
e53c0994 PZ |
5067 | u64 total = 0; |
5068 | ||
59ed446f PZ |
5069 | *enabled = 0; |
5070 | *running = 0; | |
5071 | ||
6f10581a | 5072 | mutex_lock(&event->child_mutex); |
01add3ea | 5073 | |
7d88962e | 5074 | (void)perf_event_read(event, false); |
01add3ea SB |
5075 | total += perf_event_count(event); |
5076 | ||
59ed446f PZ |
5077 | *enabled += event->total_time_enabled + |
5078 | atomic64_read(&event->child_total_time_enabled); | |
5079 | *running += event->total_time_running + | |
5080 | atomic64_read(&event->child_total_time_running); | |
5081 | ||
5082 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5083 | (void)perf_event_read(child, false); |
01add3ea | 5084 | total += perf_event_count(child); |
59ed446f PZ |
5085 | *enabled += child->total_time_enabled; |
5086 | *running += child->total_time_running; | |
5087 | } | |
6f10581a | 5088 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5089 | |
5090 | return total; | |
5091 | } | |
ca0dd44c PZ |
5092 | |
5093 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5094 | { | |
5095 | struct perf_event_context *ctx; | |
5096 | u64 count; | |
5097 | ||
5098 | ctx = perf_event_ctx_lock(event); | |
5099 | count = __perf_event_read_value(event, enabled, running); | |
5100 | perf_event_ctx_unlock(event, ctx); | |
5101 | ||
5102 | return count; | |
5103 | } | |
fb0459d7 | 5104 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5105 | |
7d88962e | 5106 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5107 | u64 read_format, u64 *values) |
3dab77fb | 5108 | { |
2aeb1883 | 5109 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5110 | struct perf_event *sub; |
2aeb1883 | 5111 | unsigned long flags; |
fa8c2693 | 5112 | int n = 1; /* skip @nr */ |
7d88962e | 5113 | int ret; |
f63a8daa | 5114 | |
7d88962e SB |
5115 | ret = perf_event_read(leader, true); |
5116 | if (ret) | |
5117 | return ret; | |
abf4868b | 5118 | |
a9cd8194 PZ |
5119 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5120 | ||
fa8c2693 PZ |
5121 | /* |
5122 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5123 | * will be identical to those of the leader, so we only publish one | |
5124 | * set. | |
5125 | */ | |
5126 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5127 | values[n++] += leader->total_time_enabled + | |
5128 | atomic64_read(&leader->child_total_time_enabled); | |
5129 | } | |
3dab77fb | 5130 | |
fa8c2693 PZ |
5131 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5132 | values[n++] += leader->total_time_running + | |
5133 | atomic64_read(&leader->child_total_time_running); | |
5134 | } | |
5135 | ||
5136 | /* | |
5137 | * Write {count,id} tuples for every sibling. | |
5138 | */ | |
5139 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5140 | if (read_format & PERF_FORMAT_ID) |
5141 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5142 | |
edb39592 | 5143 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5144 | values[n++] += perf_event_count(sub); |
5145 | if (read_format & PERF_FORMAT_ID) | |
5146 | values[n++] = primary_event_id(sub); | |
5147 | } | |
7d88962e | 5148 | |
2aeb1883 | 5149 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5150 | return 0; |
fa8c2693 | 5151 | } |
3dab77fb | 5152 | |
fa8c2693 PZ |
5153 | static int perf_read_group(struct perf_event *event, |
5154 | u64 read_format, char __user *buf) | |
5155 | { | |
5156 | struct perf_event *leader = event->group_leader, *child; | |
5157 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5158 | int ret; |
fa8c2693 | 5159 | u64 *values; |
3dab77fb | 5160 | |
fa8c2693 | 5161 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5162 | |
fa8c2693 PZ |
5163 | values = kzalloc(event->read_size, GFP_KERNEL); |
5164 | if (!values) | |
5165 | return -ENOMEM; | |
3dab77fb | 5166 | |
fa8c2693 PZ |
5167 | values[0] = 1 + leader->nr_siblings; |
5168 | ||
5169 | /* | |
5170 | * By locking the child_mutex of the leader we effectively | |
5171 | * lock the child list of all siblings.. XXX explain how. | |
5172 | */ | |
5173 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5174 | |
7d88962e SB |
5175 | ret = __perf_read_group_add(leader, read_format, values); |
5176 | if (ret) | |
5177 | goto unlock; | |
5178 | ||
5179 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5180 | ret = __perf_read_group_add(child, read_format, values); | |
5181 | if (ret) | |
5182 | goto unlock; | |
5183 | } | |
abf4868b | 5184 | |
fa8c2693 | 5185 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5186 | |
7d88962e | 5187 | ret = event->read_size; |
fa8c2693 PZ |
5188 | if (copy_to_user(buf, values, event->read_size)) |
5189 | ret = -EFAULT; | |
7d88962e | 5190 | goto out; |
fa8c2693 | 5191 | |
7d88962e SB |
5192 | unlock: |
5193 | mutex_unlock(&leader->child_mutex); | |
5194 | out: | |
fa8c2693 | 5195 | kfree(values); |
abf4868b | 5196 | return ret; |
3dab77fb PZ |
5197 | } |
5198 | ||
b15f495b | 5199 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5200 | u64 read_format, char __user *buf) |
5201 | { | |
59ed446f | 5202 | u64 enabled, running; |
3dab77fb PZ |
5203 | u64 values[4]; |
5204 | int n = 0; | |
5205 | ||
ca0dd44c | 5206 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5207 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5208 | values[n++] = enabled; | |
5209 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5210 | values[n++] = running; | |
3dab77fb | 5211 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5212 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5213 | |
5214 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5215 | return -EFAULT; | |
5216 | ||
5217 | return n * sizeof(u64); | |
5218 | } | |
5219 | ||
dc633982 JO |
5220 | static bool is_event_hup(struct perf_event *event) |
5221 | { | |
5222 | bool no_children; | |
5223 | ||
a69b0ca4 | 5224 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5225 | return false; |
5226 | ||
5227 | mutex_lock(&event->child_mutex); | |
5228 | no_children = list_empty(&event->child_list); | |
5229 | mutex_unlock(&event->child_mutex); | |
5230 | return no_children; | |
5231 | } | |
5232 | ||
0793a61d | 5233 | /* |
cdd6c482 | 5234 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5235 | */ |
5236 | static ssize_t | |
b15f495b | 5237 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5238 | { |
cdd6c482 | 5239 | u64 read_format = event->attr.read_format; |
3dab77fb | 5240 | int ret; |
0793a61d | 5241 | |
3b6f9e5c | 5242 | /* |
788faab7 | 5243 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5244 | * error state (i.e. because it was pinned but it couldn't be |
5245 | * scheduled on to the CPU at some point). | |
5246 | */ | |
cdd6c482 | 5247 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5248 | return 0; |
5249 | ||
c320c7b7 | 5250 | if (count < event->read_size) |
3dab77fb PZ |
5251 | return -ENOSPC; |
5252 | ||
cdd6c482 | 5253 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5254 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5255 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5256 | else |
b15f495b | 5257 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5258 | |
3dab77fb | 5259 | return ret; |
0793a61d TG |
5260 | } |
5261 | ||
0793a61d TG |
5262 | static ssize_t |
5263 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5264 | { | |
cdd6c482 | 5265 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5266 | struct perf_event_context *ctx; |
5267 | int ret; | |
0793a61d | 5268 | |
da97e184 JFG |
5269 | ret = security_perf_event_read(event); |
5270 | if (ret) | |
5271 | return ret; | |
5272 | ||
f63a8daa | 5273 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5274 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5275 | perf_event_ctx_unlock(event, ctx); |
5276 | ||
5277 | return ret; | |
0793a61d TG |
5278 | } |
5279 | ||
9dd95748 | 5280 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5281 | { |
cdd6c482 | 5282 | struct perf_event *event = file->private_data; |
56de4e8f | 5283 | struct perf_buffer *rb; |
a9a08845 | 5284 | __poll_t events = EPOLLHUP; |
c7138f37 | 5285 | |
e708d7ad | 5286 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5287 | |
dc633982 | 5288 | if (is_event_hup(event)) |
179033b3 | 5289 | return events; |
c7138f37 | 5290 | |
10c6db11 | 5291 | /* |
9bb5d40c PZ |
5292 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5293 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5294 | */ |
5295 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5296 | rb = event->rb; |
5297 | if (rb) | |
76369139 | 5298 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5299 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5300 | return events; |
5301 | } | |
5302 | ||
f63a8daa | 5303 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5304 | { |
7d88962e | 5305 | (void)perf_event_read(event, false); |
e7850595 | 5306 | local64_set(&event->count, 0); |
cdd6c482 | 5307 | perf_event_update_userpage(event); |
3df5edad PZ |
5308 | } |
5309 | ||
52ba4b0b LX |
5310 | /* Assume it's not an event with inherit set. */ |
5311 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5312 | { | |
5313 | struct perf_event_context *ctx; | |
5314 | u64 count; | |
5315 | ||
5316 | ctx = perf_event_ctx_lock(event); | |
5317 | WARN_ON_ONCE(event->attr.inherit); | |
5318 | _perf_event_disable(event); | |
5319 | count = local64_read(&event->count); | |
5320 | if (reset) | |
5321 | local64_set(&event->count, 0); | |
5322 | perf_event_ctx_unlock(event, ctx); | |
5323 | ||
5324 | return count; | |
5325 | } | |
5326 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5327 | ||
c93f7669 | 5328 | /* |
cdd6c482 IM |
5329 | * Holding the top-level event's child_mutex means that any |
5330 | * descendant process that has inherited this event will block | |
8ba289b8 | 5331 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5332 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5333 | */ |
cdd6c482 IM |
5334 | static void perf_event_for_each_child(struct perf_event *event, |
5335 | void (*func)(struct perf_event *)) | |
3df5edad | 5336 | { |
cdd6c482 | 5337 | struct perf_event *child; |
3df5edad | 5338 | |
cdd6c482 | 5339 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5340 | |
cdd6c482 IM |
5341 | mutex_lock(&event->child_mutex); |
5342 | func(event); | |
5343 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5344 | func(child); |
cdd6c482 | 5345 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5346 | } |
5347 | ||
cdd6c482 IM |
5348 | static void perf_event_for_each(struct perf_event *event, |
5349 | void (*func)(struct perf_event *)) | |
3df5edad | 5350 | { |
cdd6c482 IM |
5351 | struct perf_event_context *ctx = event->ctx; |
5352 | struct perf_event *sibling; | |
3df5edad | 5353 | |
f63a8daa PZ |
5354 | lockdep_assert_held(&ctx->mutex); |
5355 | ||
cdd6c482 | 5356 | event = event->group_leader; |
75f937f2 | 5357 | |
cdd6c482 | 5358 | perf_event_for_each_child(event, func); |
edb39592 | 5359 | for_each_sibling_event(sibling, event) |
724b6daa | 5360 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5361 | } |
5362 | ||
fae3fde6 PZ |
5363 | static void __perf_event_period(struct perf_event *event, |
5364 | struct perf_cpu_context *cpuctx, | |
5365 | struct perf_event_context *ctx, | |
5366 | void *info) | |
c7999c6f | 5367 | { |
fae3fde6 | 5368 | u64 value = *((u64 *)info); |
c7999c6f | 5369 | bool active; |
08247e31 | 5370 | |
cdd6c482 | 5371 | if (event->attr.freq) { |
cdd6c482 | 5372 | event->attr.sample_freq = value; |
08247e31 | 5373 | } else { |
cdd6c482 IM |
5374 | event->attr.sample_period = value; |
5375 | event->hw.sample_period = value; | |
08247e31 | 5376 | } |
bad7192b PZ |
5377 | |
5378 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5379 | if (active) { | |
5380 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5381 | /* |
5382 | * We could be throttled; unthrottle now to avoid the tick | |
5383 | * trying to unthrottle while we already re-started the event. | |
5384 | */ | |
5385 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5386 | event->hw.interrupts = 0; | |
5387 | perf_log_throttle(event, 1); | |
5388 | } | |
bad7192b PZ |
5389 | event->pmu->stop(event, PERF_EF_UPDATE); |
5390 | } | |
5391 | ||
5392 | local64_set(&event->hw.period_left, 0); | |
5393 | ||
5394 | if (active) { | |
5395 | event->pmu->start(event, PERF_EF_RELOAD); | |
5396 | perf_pmu_enable(ctx->pmu); | |
5397 | } | |
c7999c6f PZ |
5398 | } |
5399 | ||
81ec3f3c JO |
5400 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5401 | { | |
5402 | return event->pmu->check_period(event, value); | |
5403 | } | |
5404 | ||
3ca270fc | 5405 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5406 | { |
c7999c6f PZ |
5407 | if (!is_sampling_event(event)) |
5408 | return -EINVAL; | |
5409 | ||
c7999c6f PZ |
5410 | if (!value) |
5411 | return -EINVAL; | |
5412 | ||
5413 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5414 | return -EINVAL; | |
5415 | ||
81ec3f3c JO |
5416 | if (perf_event_check_period(event, value)) |
5417 | return -EINVAL; | |
5418 | ||
913a90bc RB |
5419 | if (!event->attr.freq && (value & (1ULL << 63))) |
5420 | return -EINVAL; | |
5421 | ||
fae3fde6 | 5422 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5423 | |
c7999c6f | 5424 | return 0; |
08247e31 PZ |
5425 | } |
5426 | ||
3ca270fc LX |
5427 | int perf_event_period(struct perf_event *event, u64 value) |
5428 | { | |
5429 | struct perf_event_context *ctx; | |
5430 | int ret; | |
5431 | ||
5432 | ctx = perf_event_ctx_lock(event); | |
5433 | ret = _perf_event_period(event, value); | |
5434 | perf_event_ctx_unlock(event, ctx); | |
5435 | ||
5436 | return ret; | |
5437 | } | |
5438 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5439 | ||
ac9721f3 PZ |
5440 | static const struct file_operations perf_fops; |
5441 | ||
2903ff01 | 5442 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5443 | { |
2903ff01 AV |
5444 | struct fd f = fdget(fd); |
5445 | if (!f.file) | |
5446 | return -EBADF; | |
ac9721f3 | 5447 | |
2903ff01 AV |
5448 | if (f.file->f_op != &perf_fops) { |
5449 | fdput(f); | |
5450 | return -EBADF; | |
ac9721f3 | 5451 | } |
2903ff01 AV |
5452 | *p = f; |
5453 | return 0; | |
ac9721f3 PZ |
5454 | } |
5455 | ||
5456 | static int perf_event_set_output(struct perf_event *event, | |
5457 | struct perf_event *output_event); | |
6fb2915d | 5458 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5459 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5460 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5461 | struct perf_event_attr *attr); | |
a4be7c27 | 5462 | |
f63a8daa | 5463 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5464 | { |
cdd6c482 | 5465 | void (*func)(struct perf_event *); |
3df5edad | 5466 | u32 flags = arg; |
d859e29f PM |
5467 | |
5468 | switch (cmd) { | |
cdd6c482 | 5469 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5470 | func = _perf_event_enable; |
d859e29f | 5471 | break; |
cdd6c482 | 5472 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5473 | func = _perf_event_disable; |
79f14641 | 5474 | break; |
cdd6c482 | 5475 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5476 | func = _perf_event_reset; |
6de6a7b9 | 5477 | break; |
3df5edad | 5478 | |
cdd6c482 | 5479 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5480 | return _perf_event_refresh(event, arg); |
08247e31 | 5481 | |
cdd6c482 | 5482 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5483 | { |
5484 | u64 value; | |
08247e31 | 5485 | |
3ca270fc LX |
5486 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5487 | return -EFAULT; | |
08247e31 | 5488 | |
3ca270fc LX |
5489 | return _perf_event_period(event, value); |
5490 | } | |
cf4957f1 JO |
5491 | case PERF_EVENT_IOC_ID: |
5492 | { | |
5493 | u64 id = primary_event_id(event); | |
5494 | ||
5495 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5496 | return -EFAULT; | |
5497 | return 0; | |
5498 | } | |
5499 | ||
cdd6c482 | 5500 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5501 | { |
ac9721f3 | 5502 | int ret; |
ac9721f3 | 5503 | if (arg != -1) { |
2903ff01 AV |
5504 | struct perf_event *output_event; |
5505 | struct fd output; | |
5506 | ret = perf_fget_light(arg, &output); | |
5507 | if (ret) | |
5508 | return ret; | |
5509 | output_event = output.file->private_data; | |
5510 | ret = perf_event_set_output(event, output_event); | |
5511 | fdput(output); | |
5512 | } else { | |
5513 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5514 | } |
ac9721f3 PZ |
5515 | return ret; |
5516 | } | |
a4be7c27 | 5517 | |
6fb2915d LZ |
5518 | case PERF_EVENT_IOC_SET_FILTER: |
5519 | return perf_event_set_filter(event, (void __user *)arg); | |
5520 | ||
2541517c AS |
5521 | case PERF_EVENT_IOC_SET_BPF: |
5522 | return perf_event_set_bpf_prog(event, arg); | |
5523 | ||
86e7972f | 5524 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5525 | struct perf_buffer *rb; |
86e7972f WN |
5526 | |
5527 | rcu_read_lock(); | |
5528 | rb = rcu_dereference(event->rb); | |
5529 | if (!rb || !rb->nr_pages) { | |
5530 | rcu_read_unlock(); | |
5531 | return -EINVAL; | |
5532 | } | |
5533 | rb_toggle_paused(rb, !!arg); | |
5534 | rcu_read_unlock(); | |
5535 | return 0; | |
5536 | } | |
f371b304 YS |
5537 | |
5538 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5539 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5540 | |
5541 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5542 | struct perf_event_attr new_attr; | |
5543 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5544 | &new_attr); | |
5545 | ||
5546 | if (err) | |
5547 | return err; | |
5548 | ||
5549 | return perf_event_modify_attr(event, &new_attr); | |
5550 | } | |
d859e29f | 5551 | default: |
3df5edad | 5552 | return -ENOTTY; |
d859e29f | 5553 | } |
3df5edad PZ |
5554 | |
5555 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5556 | perf_event_for_each(event, func); |
3df5edad | 5557 | else |
cdd6c482 | 5558 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5559 | |
5560 | return 0; | |
d859e29f PM |
5561 | } |
5562 | ||
f63a8daa PZ |
5563 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5564 | { | |
5565 | struct perf_event *event = file->private_data; | |
5566 | struct perf_event_context *ctx; | |
5567 | long ret; | |
5568 | ||
da97e184 JFG |
5569 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5570 | ret = security_perf_event_write(event); | |
5571 | if (ret) | |
5572 | return ret; | |
5573 | ||
f63a8daa PZ |
5574 | ctx = perf_event_ctx_lock(event); |
5575 | ret = _perf_ioctl(event, cmd, arg); | |
5576 | perf_event_ctx_unlock(event, ctx); | |
5577 | ||
5578 | return ret; | |
5579 | } | |
5580 | ||
b3f20785 PM |
5581 | #ifdef CONFIG_COMPAT |
5582 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5583 | unsigned long arg) | |
5584 | { | |
5585 | switch (_IOC_NR(cmd)) { | |
5586 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5587 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5588 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5589 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5590 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5591 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5592 | cmd &= ~IOCSIZE_MASK; | |
5593 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5594 | } | |
5595 | break; | |
5596 | } | |
5597 | return perf_ioctl(file, cmd, arg); | |
5598 | } | |
5599 | #else | |
5600 | # define perf_compat_ioctl NULL | |
5601 | #endif | |
5602 | ||
cdd6c482 | 5603 | int perf_event_task_enable(void) |
771d7cde | 5604 | { |
f63a8daa | 5605 | struct perf_event_context *ctx; |
cdd6c482 | 5606 | struct perf_event *event; |
771d7cde | 5607 | |
cdd6c482 | 5608 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5609 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5610 | ctx = perf_event_ctx_lock(event); | |
5611 | perf_event_for_each_child(event, _perf_event_enable); | |
5612 | perf_event_ctx_unlock(event, ctx); | |
5613 | } | |
cdd6c482 | 5614 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5615 | |
5616 | return 0; | |
5617 | } | |
5618 | ||
cdd6c482 | 5619 | int perf_event_task_disable(void) |
771d7cde | 5620 | { |
f63a8daa | 5621 | struct perf_event_context *ctx; |
cdd6c482 | 5622 | struct perf_event *event; |
771d7cde | 5623 | |
cdd6c482 | 5624 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5625 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5626 | ctx = perf_event_ctx_lock(event); | |
5627 | perf_event_for_each_child(event, _perf_event_disable); | |
5628 | perf_event_ctx_unlock(event, ctx); | |
5629 | } | |
cdd6c482 | 5630 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5631 | |
5632 | return 0; | |
5633 | } | |
5634 | ||
cdd6c482 | 5635 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5636 | { |
a4eaf7f1 PZ |
5637 | if (event->hw.state & PERF_HES_STOPPED) |
5638 | return 0; | |
5639 | ||
cdd6c482 | 5640 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5641 | return 0; |
5642 | ||
35edc2a5 | 5643 | return event->pmu->event_idx(event); |
194002b2 PZ |
5644 | } |
5645 | ||
c4794295 | 5646 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5647 | u64 *now, |
7f310a5d EM |
5648 | u64 *enabled, |
5649 | u64 *running) | |
c4794295 | 5650 | { |
e3f3541c | 5651 | u64 ctx_time; |
c4794295 | 5652 | |
e3f3541c PZ |
5653 | *now = perf_clock(); |
5654 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5655 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5656 | } |
5657 | ||
fa731587 PZ |
5658 | static void perf_event_init_userpage(struct perf_event *event) |
5659 | { | |
5660 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5661 | struct perf_buffer *rb; |
fa731587 PZ |
5662 | |
5663 | rcu_read_lock(); | |
5664 | rb = rcu_dereference(event->rb); | |
5665 | if (!rb) | |
5666 | goto unlock; | |
5667 | ||
5668 | userpg = rb->user_page; | |
5669 | ||
5670 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5671 | userpg->cap_bit0_is_deprecated = 1; | |
5672 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5673 | userpg->data_offset = PAGE_SIZE; |
5674 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5675 | |
5676 | unlock: | |
5677 | rcu_read_unlock(); | |
5678 | } | |
5679 | ||
c1317ec2 AL |
5680 | void __weak arch_perf_update_userpage( |
5681 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5682 | { |
5683 | } | |
5684 | ||
38ff667b PZ |
5685 | /* |
5686 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5687 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5688 | * code calls this from NMI context. | |
5689 | */ | |
cdd6c482 | 5690 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5691 | { |
cdd6c482 | 5692 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5693 | struct perf_buffer *rb; |
e3f3541c | 5694 | u64 enabled, running, now; |
38ff667b PZ |
5695 | |
5696 | rcu_read_lock(); | |
5ec4c599 PZ |
5697 | rb = rcu_dereference(event->rb); |
5698 | if (!rb) | |
5699 | goto unlock; | |
5700 | ||
0d641208 EM |
5701 | /* |
5702 | * compute total_time_enabled, total_time_running | |
5703 | * based on snapshot values taken when the event | |
5704 | * was last scheduled in. | |
5705 | * | |
5706 | * we cannot simply called update_context_time() | |
5707 | * because of locking issue as we can be called in | |
5708 | * NMI context | |
5709 | */ | |
e3f3541c | 5710 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5711 | |
76369139 | 5712 | userpg = rb->user_page; |
7b732a75 | 5713 | /* |
9d2dcc8f MF |
5714 | * Disable preemption to guarantee consistent time stamps are stored to |
5715 | * the user page. | |
7b732a75 PZ |
5716 | */ |
5717 | preempt_disable(); | |
37d81828 | 5718 | ++userpg->lock; |
92f22a38 | 5719 | barrier(); |
cdd6c482 | 5720 | userpg->index = perf_event_index(event); |
b5e58793 | 5721 | userpg->offset = perf_event_count(event); |
365a4038 | 5722 | if (userpg->index) |
e7850595 | 5723 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5724 | |
0d641208 | 5725 | userpg->time_enabled = enabled + |
cdd6c482 | 5726 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5727 | |
0d641208 | 5728 | userpg->time_running = running + |
cdd6c482 | 5729 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5730 | |
c1317ec2 | 5731 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5732 | |
92f22a38 | 5733 | barrier(); |
37d81828 | 5734 | ++userpg->lock; |
7b732a75 | 5735 | preempt_enable(); |
38ff667b | 5736 | unlock: |
7b732a75 | 5737 | rcu_read_unlock(); |
37d81828 | 5738 | } |
82975c46 | 5739 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5740 | |
9e3ed2d7 | 5741 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5742 | { |
11bac800 | 5743 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5744 | struct perf_buffer *rb; |
9e3ed2d7 | 5745 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5746 | |
5747 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5748 | if (vmf->pgoff == 0) | |
5749 | ret = 0; | |
5750 | return ret; | |
5751 | } | |
5752 | ||
5753 | rcu_read_lock(); | |
76369139 FW |
5754 | rb = rcu_dereference(event->rb); |
5755 | if (!rb) | |
906010b2 PZ |
5756 | goto unlock; |
5757 | ||
5758 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5759 | goto unlock; | |
5760 | ||
76369139 | 5761 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5762 | if (!vmf->page) |
5763 | goto unlock; | |
5764 | ||
5765 | get_page(vmf->page); | |
11bac800 | 5766 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5767 | vmf->page->index = vmf->pgoff; |
5768 | ||
5769 | ret = 0; | |
5770 | unlock: | |
5771 | rcu_read_unlock(); | |
5772 | ||
5773 | return ret; | |
5774 | } | |
5775 | ||
10c6db11 | 5776 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5777 | struct perf_buffer *rb) |
10c6db11 | 5778 | { |
56de4e8f | 5779 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5780 | unsigned long flags; |
5781 | ||
b69cf536 PZ |
5782 | if (event->rb) { |
5783 | /* | |
5784 | * Should be impossible, we set this when removing | |
5785 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5786 | */ | |
5787 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5788 | |
b69cf536 | 5789 | old_rb = event->rb; |
b69cf536 PZ |
5790 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5791 | list_del_rcu(&event->rb_entry); | |
5792 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5793 | |
2f993cf0 ON |
5794 | event->rcu_batches = get_state_synchronize_rcu(); |
5795 | event->rcu_pending = 1; | |
b69cf536 | 5796 | } |
10c6db11 | 5797 | |
b69cf536 | 5798 | if (rb) { |
2f993cf0 ON |
5799 | if (event->rcu_pending) { |
5800 | cond_synchronize_rcu(event->rcu_batches); | |
5801 | event->rcu_pending = 0; | |
5802 | } | |
5803 | ||
b69cf536 PZ |
5804 | spin_lock_irqsave(&rb->event_lock, flags); |
5805 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5806 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5807 | } | |
5808 | ||
767ae086 AS |
5809 | /* |
5810 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5811 | * before swizzling the event::rb pointer; if it's getting | |
5812 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5813 | * restart. See the comment in __perf_pmu_output_stop(). | |
5814 | * | |
5815 | * Data will inevitably be lost when set_output is done in | |
5816 | * mid-air, but then again, whoever does it like this is | |
5817 | * not in for the data anyway. | |
5818 | */ | |
5819 | if (has_aux(event)) | |
5820 | perf_event_stop(event, 0); | |
5821 | ||
b69cf536 PZ |
5822 | rcu_assign_pointer(event->rb, rb); |
5823 | ||
5824 | if (old_rb) { | |
5825 | ring_buffer_put(old_rb); | |
5826 | /* | |
5827 | * Since we detached before setting the new rb, so that we | |
5828 | * could attach the new rb, we could have missed a wakeup. | |
5829 | * Provide it now. | |
5830 | */ | |
5831 | wake_up_all(&event->waitq); | |
5832 | } | |
10c6db11 PZ |
5833 | } |
5834 | ||
5835 | static void ring_buffer_wakeup(struct perf_event *event) | |
5836 | { | |
56de4e8f | 5837 | struct perf_buffer *rb; |
10c6db11 PZ |
5838 | |
5839 | rcu_read_lock(); | |
5840 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5841 | if (rb) { |
5842 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5843 | wake_up_all(&event->waitq); | |
5844 | } | |
10c6db11 PZ |
5845 | rcu_read_unlock(); |
5846 | } | |
5847 | ||
56de4e8f | 5848 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5849 | { |
56de4e8f | 5850 | struct perf_buffer *rb; |
7b732a75 | 5851 | |
ac9721f3 | 5852 | rcu_read_lock(); |
76369139 FW |
5853 | rb = rcu_dereference(event->rb); |
5854 | if (rb) { | |
fecb8ed2 | 5855 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5856 | rb = NULL; |
ac9721f3 PZ |
5857 | } |
5858 | rcu_read_unlock(); | |
5859 | ||
76369139 | 5860 | return rb; |
ac9721f3 PZ |
5861 | } |
5862 | ||
56de4e8f | 5863 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5864 | { |
fecb8ed2 | 5865 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5866 | return; |
7b732a75 | 5867 | |
9bb5d40c | 5868 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5869 | |
76369139 | 5870 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5871 | } |
5872 | ||
5873 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5874 | { | |
cdd6c482 | 5875 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5876 | |
cdd6c482 | 5877 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5878 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5879 | |
45bfb2e5 PZ |
5880 | if (vma->vm_pgoff) |
5881 | atomic_inc(&event->rb->aux_mmap_count); | |
5882 | ||
1e0fb9ec | 5883 | if (event->pmu->event_mapped) |
bfe33492 | 5884 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5885 | } |
5886 | ||
95ff4ca2 AS |
5887 | static void perf_pmu_output_stop(struct perf_event *event); |
5888 | ||
9bb5d40c PZ |
5889 | /* |
5890 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5891 | * event, or through other events by use of perf_event_set_output(). | |
5892 | * | |
5893 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5894 | * the buffer here, where we still have a VM context. This means we need | |
5895 | * to detach all events redirecting to us. | |
5896 | */ | |
7b732a75 PZ |
5897 | static void perf_mmap_close(struct vm_area_struct *vma) |
5898 | { | |
cdd6c482 | 5899 | struct perf_event *event = vma->vm_file->private_data; |
56de4e8f | 5900 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5901 | struct user_struct *mmap_user = rb->mmap_user; |
5902 | int mmap_locked = rb->mmap_locked; | |
5903 | unsigned long size = perf_data_size(rb); | |
f91072ed | 5904 | bool detach_rest = false; |
789f90fc | 5905 | |
1e0fb9ec | 5906 | if (event->pmu->event_unmapped) |
bfe33492 | 5907 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5908 | |
45bfb2e5 PZ |
5909 | /* |
5910 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5911 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5912 | * serialize with perf_mmap here. | |
5913 | */ | |
5914 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5915 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5916 | /* |
5917 | * Stop all AUX events that are writing to this buffer, | |
5918 | * so that we can free its AUX pages and corresponding PMU | |
5919 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5920 | * they won't start any more (see perf_aux_output_begin()). | |
5921 | */ | |
5922 | perf_pmu_output_stop(event); | |
5923 | ||
5924 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5925 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5926 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5927 | |
95ff4ca2 | 5928 | /* this has to be the last one */ |
45bfb2e5 | 5929 | rb_free_aux(rb); |
ca3bb3d0 | 5930 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5931 | |
45bfb2e5 PZ |
5932 | mutex_unlock(&event->mmap_mutex); |
5933 | } | |
5934 | ||
f91072ed JO |
5935 | if (atomic_dec_and_test(&rb->mmap_count)) |
5936 | detach_rest = true; | |
9bb5d40c PZ |
5937 | |
5938 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5939 | goto out_put; |
9bb5d40c | 5940 | |
b69cf536 | 5941 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5942 | mutex_unlock(&event->mmap_mutex); |
5943 | ||
5944 | /* If there's still other mmap()s of this buffer, we're done. */ | |
f91072ed | 5945 | if (!detach_rest) |
b69cf536 | 5946 | goto out_put; |
ac9721f3 | 5947 | |
9bb5d40c PZ |
5948 | /* |
5949 | * No other mmap()s, detach from all other events that might redirect | |
5950 | * into the now unreachable buffer. Somewhat complicated by the | |
5951 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5952 | */ | |
5953 | again: | |
5954 | rcu_read_lock(); | |
5955 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5956 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5957 | /* | |
5958 | * This event is en-route to free_event() which will | |
5959 | * detach it and remove it from the list. | |
5960 | */ | |
5961 | continue; | |
5962 | } | |
5963 | rcu_read_unlock(); | |
789f90fc | 5964 | |
9bb5d40c PZ |
5965 | mutex_lock(&event->mmap_mutex); |
5966 | /* | |
5967 | * Check we didn't race with perf_event_set_output() which can | |
5968 | * swizzle the rb from under us while we were waiting to | |
5969 | * acquire mmap_mutex. | |
5970 | * | |
5971 | * If we find a different rb; ignore this event, a next | |
5972 | * iteration will no longer find it on the list. We have to | |
5973 | * still restart the iteration to make sure we're not now | |
5974 | * iterating the wrong list. | |
5975 | */ | |
b69cf536 PZ |
5976 | if (event->rb == rb) |
5977 | ring_buffer_attach(event, NULL); | |
5978 | ||
cdd6c482 | 5979 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5980 | put_event(event); |
ac9721f3 | 5981 | |
9bb5d40c PZ |
5982 | /* |
5983 | * Restart the iteration; either we're on the wrong list or | |
5984 | * destroyed its integrity by doing a deletion. | |
5985 | */ | |
5986 | goto again; | |
7b732a75 | 5987 | } |
9bb5d40c PZ |
5988 | rcu_read_unlock(); |
5989 | ||
5990 | /* | |
5991 | * It could be there's still a few 0-ref events on the list; they'll | |
5992 | * get cleaned up by free_event() -- they'll also still have their | |
5993 | * ref on the rb and will free it whenever they are done with it. | |
5994 | * | |
5995 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5996 | * undo the VM accounting. | |
5997 | */ | |
5998 | ||
d44248a4 SL |
5999 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
6000 | &mmap_user->locked_vm); | |
70f8a3ca | 6001 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
6002 | free_uid(mmap_user); |
6003 | ||
b69cf536 | 6004 | out_put: |
9bb5d40c | 6005 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
6006 | } |
6007 | ||
f0f37e2f | 6008 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 6009 | .open = perf_mmap_open, |
fca0c116 | 6010 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
6011 | .fault = perf_mmap_fault, |
6012 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
6013 | }; |
6014 | ||
6015 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
6016 | { | |
cdd6c482 | 6017 | struct perf_event *event = file->private_data; |
22a4f650 | 6018 | unsigned long user_locked, user_lock_limit; |
789f90fc | 6019 | struct user_struct *user = current_user(); |
56de4e8f | 6020 | struct perf_buffer *rb = NULL; |
22a4f650 | 6021 | unsigned long locked, lock_limit; |
7b732a75 PZ |
6022 | unsigned long vma_size; |
6023 | unsigned long nr_pages; | |
45bfb2e5 | 6024 | long user_extra = 0, extra = 0; |
d57e34fd | 6025 | int ret = 0, flags = 0; |
37d81828 | 6026 | |
c7920614 PZ |
6027 | /* |
6028 | * Don't allow mmap() of inherited per-task counters. This would | |
6029 | * create a performance issue due to all children writing to the | |
76369139 | 6030 | * same rb. |
c7920614 PZ |
6031 | */ |
6032 | if (event->cpu == -1 && event->attr.inherit) | |
6033 | return -EINVAL; | |
6034 | ||
43a21ea8 | 6035 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 6036 | return -EINVAL; |
7b732a75 | 6037 | |
da97e184 JFG |
6038 | ret = security_perf_event_read(event); |
6039 | if (ret) | |
6040 | return ret; | |
6041 | ||
7b732a75 | 6042 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
6043 | |
6044 | if (vma->vm_pgoff == 0) { | |
6045 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
6046 | } else { | |
6047 | /* | |
6048 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
6049 | * mapped, all subsequent mappings should have the same size | |
6050 | * and offset. Must be above the normal perf buffer. | |
6051 | */ | |
6052 | u64 aux_offset, aux_size; | |
6053 | ||
6054 | if (!event->rb) | |
6055 | return -EINVAL; | |
6056 | ||
6057 | nr_pages = vma_size / PAGE_SIZE; | |
6058 | ||
6059 | mutex_lock(&event->mmap_mutex); | |
6060 | ret = -EINVAL; | |
6061 | ||
6062 | rb = event->rb; | |
6063 | if (!rb) | |
6064 | goto aux_unlock; | |
6065 | ||
6aa7de05 MR |
6066 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
6067 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6068 | |
6069 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6070 | goto aux_unlock; | |
6071 | ||
6072 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6073 | goto aux_unlock; | |
6074 | ||
6075 | /* already mapped with a different offset */ | |
6076 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6077 | goto aux_unlock; | |
6078 | ||
6079 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6080 | goto aux_unlock; | |
6081 | ||
6082 | /* already mapped with a different size */ | |
6083 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6084 | goto aux_unlock; | |
6085 | ||
6086 | if (!is_power_of_2(nr_pages)) | |
6087 | goto aux_unlock; | |
6088 | ||
6089 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6090 | goto aux_unlock; | |
6091 | ||
6092 | if (rb_has_aux(rb)) { | |
6093 | atomic_inc(&rb->aux_mmap_count); | |
6094 | ret = 0; | |
6095 | goto unlock; | |
6096 | } | |
6097 | ||
6098 | atomic_set(&rb->aux_mmap_count, 1); | |
6099 | user_extra = nr_pages; | |
6100 | ||
6101 | goto accounting; | |
6102 | } | |
7b732a75 | 6103 | |
7730d865 | 6104 | /* |
76369139 | 6105 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6106 | * can do bitmasks instead of modulo. |
6107 | */ | |
2ed11312 | 6108 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6109 | return -EINVAL; |
6110 | ||
7b732a75 | 6111 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6112 | return -EINVAL; |
6113 | ||
cdd6c482 | 6114 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6115 | again: |
cdd6c482 | 6116 | mutex_lock(&event->mmap_mutex); |
76369139 | 6117 | if (event->rb) { |
9bb5d40c | 6118 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6119 | ret = -EINVAL; |
9bb5d40c PZ |
6120 | goto unlock; |
6121 | } | |
6122 | ||
6123 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6124 | /* | |
6125 | * Raced against perf_mmap_close() through | |
6126 | * perf_event_set_output(). Try again, hope for better | |
6127 | * luck. | |
6128 | */ | |
6129 | mutex_unlock(&event->mmap_mutex); | |
6130 | goto again; | |
6131 | } | |
6132 | ||
ebb3c4c4 PZ |
6133 | goto unlock; |
6134 | } | |
6135 | ||
789f90fc | 6136 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6137 | |
6138 | accounting: | |
cdd6c482 | 6139 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6140 | |
6141 | /* | |
6142 | * Increase the limit linearly with more CPUs: | |
6143 | */ | |
6144 | user_lock_limit *= num_online_cpus(); | |
6145 | ||
00346155 SL |
6146 | user_locked = atomic_long_read(&user->locked_vm); |
6147 | ||
6148 | /* | |
6149 | * sysctl_perf_event_mlock may have changed, so that | |
6150 | * user->locked_vm > user_lock_limit | |
6151 | */ | |
6152 | if (user_locked > user_lock_limit) | |
6153 | user_locked = user_lock_limit; | |
6154 | user_locked += user_extra; | |
c5078f78 | 6155 | |
c4b75479 | 6156 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6157 | /* |
6158 | * charge locked_vm until it hits user_lock_limit; | |
6159 | * charge the rest from pinned_vm | |
6160 | */ | |
789f90fc | 6161 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6162 | user_extra -= extra; |
6163 | } | |
7b732a75 | 6164 | |
78d7d407 | 6165 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6166 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6167 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6168 | |
da97e184 | 6169 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6170 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6171 | ret = -EPERM; |
6172 | goto unlock; | |
6173 | } | |
7b732a75 | 6174 | |
45bfb2e5 | 6175 | WARN_ON(!rb && event->rb); |
906010b2 | 6176 | |
d57e34fd | 6177 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6178 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6179 | |
76369139 | 6180 | if (!rb) { |
45bfb2e5 PZ |
6181 | rb = rb_alloc(nr_pages, |
6182 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6183 | event->cpu, flags); | |
26cb63ad | 6184 | |
45bfb2e5 PZ |
6185 | if (!rb) { |
6186 | ret = -ENOMEM; | |
6187 | goto unlock; | |
6188 | } | |
43a21ea8 | 6189 | |
45bfb2e5 PZ |
6190 | atomic_set(&rb->mmap_count, 1); |
6191 | rb->mmap_user = get_current_user(); | |
6192 | rb->mmap_locked = extra; | |
26cb63ad | 6193 | |
45bfb2e5 | 6194 | ring_buffer_attach(event, rb); |
ac9721f3 | 6195 | |
45bfb2e5 PZ |
6196 | perf_event_init_userpage(event); |
6197 | perf_event_update_userpage(event); | |
6198 | } else { | |
1a594131 AS |
6199 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6200 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6201 | if (!ret) |
6202 | rb->aux_mmap_locked = extra; | |
6203 | } | |
9a0f05cb | 6204 | |
ebb3c4c4 | 6205 | unlock: |
45bfb2e5 PZ |
6206 | if (!ret) { |
6207 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6208 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6209 | |
ac9721f3 | 6210 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6211 | } else if (rb) { |
6212 | atomic_dec(&rb->mmap_count); | |
6213 | } | |
6214 | aux_unlock: | |
cdd6c482 | 6215 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6216 | |
9bb5d40c PZ |
6217 | /* |
6218 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6219 | * vma. | |
6220 | */ | |
26cb63ad | 6221 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6222 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6223 | |
1e0fb9ec | 6224 | if (event->pmu->event_mapped) |
bfe33492 | 6225 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6226 | |
7b732a75 | 6227 | return ret; |
37d81828 PM |
6228 | } |
6229 | ||
3c446b3d PZ |
6230 | static int perf_fasync(int fd, struct file *filp, int on) |
6231 | { | |
496ad9aa | 6232 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6233 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6234 | int retval; |
6235 | ||
5955102c | 6236 | inode_lock(inode); |
cdd6c482 | 6237 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6238 | inode_unlock(inode); |
3c446b3d PZ |
6239 | |
6240 | if (retval < 0) | |
6241 | return retval; | |
6242 | ||
6243 | return 0; | |
6244 | } | |
6245 | ||
0793a61d | 6246 | static const struct file_operations perf_fops = { |
3326c1ce | 6247 | .llseek = no_llseek, |
0793a61d TG |
6248 | .release = perf_release, |
6249 | .read = perf_read, | |
6250 | .poll = perf_poll, | |
d859e29f | 6251 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6252 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6253 | .mmap = perf_mmap, |
3c446b3d | 6254 | .fasync = perf_fasync, |
0793a61d TG |
6255 | }; |
6256 | ||
925d519a | 6257 | /* |
cdd6c482 | 6258 | * Perf event wakeup |
925d519a PZ |
6259 | * |
6260 | * If there's data, ensure we set the poll() state and publish everything | |
6261 | * to user-space before waking everybody up. | |
6262 | */ | |
6263 | ||
fed66e2c PZ |
6264 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6265 | { | |
6266 | /* only the parent has fasync state */ | |
6267 | if (event->parent) | |
6268 | event = event->parent; | |
6269 | return &event->fasync; | |
6270 | } | |
6271 | ||
cdd6c482 | 6272 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6273 | { |
10c6db11 | 6274 | ring_buffer_wakeup(event); |
4c9e2542 | 6275 | |
cdd6c482 | 6276 | if (event->pending_kill) { |
fed66e2c | 6277 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6278 | event->pending_kill = 0; |
4c9e2542 | 6279 | } |
925d519a PZ |
6280 | } |
6281 | ||
1d54ad94 PZ |
6282 | static void perf_pending_event_disable(struct perf_event *event) |
6283 | { | |
6284 | int cpu = READ_ONCE(event->pending_disable); | |
6285 | ||
6286 | if (cpu < 0) | |
6287 | return; | |
6288 | ||
6289 | if (cpu == smp_processor_id()) { | |
6290 | WRITE_ONCE(event->pending_disable, -1); | |
6291 | perf_event_disable_local(event); | |
6292 | return; | |
6293 | } | |
6294 | ||
6295 | /* | |
6296 | * CPU-A CPU-B | |
6297 | * | |
6298 | * perf_event_disable_inatomic() | |
6299 | * @pending_disable = CPU-A; | |
6300 | * irq_work_queue(); | |
6301 | * | |
6302 | * sched-out | |
6303 | * @pending_disable = -1; | |
6304 | * | |
6305 | * sched-in | |
6306 | * perf_event_disable_inatomic() | |
6307 | * @pending_disable = CPU-B; | |
6308 | * irq_work_queue(); // FAILS | |
6309 | * | |
6310 | * irq_work_run() | |
6311 | * perf_pending_event() | |
6312 | * | |
6313 | * But the event runs on CPU-B and wants disabling there. | |
6314 | */ | |
6315 | irq_work_queue_on(&event->pending, cpu); | |
6316 | } | |
6317 | ||
e360adbe | 6318 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6319 | { |
1d54ad94 | 6320 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6321 | int rctx; |
6322 | ||
6323 | rctx = perf_swevent_get_recursion_context(); | |
6324 | /* | |
6325 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6326 | * and we won't recurse 'further'. | |
6327 | */ | |
79f14641 | 6328 | |
1d54ad94 | 6329 | perf_pending_event_disable(event); |
79f14641 | 6330 | |
cdd6c482 IM |
6331 | if (event->pending_wakeup) { |
6332 | event->pending_wakeup = 0; | |
6333 | perf_event_wakeup(event); | |
79f14641 | 6334 | } |
d525211f PZ |
6335 | |
6336 | if (rctx >= 0) | |
6337 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6338 | } |
6339 | ||
39447b38 ZY |
6340 | /* |
6341 | * We assume there is only KVM supporting the callbacks. | |
6342 | * Later on, we might change it to a list if there is | |
6343 | * another virtualization implementation supporting the callbacks. | |
6344 | */ | |
6345 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6346 | ||
6347 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6348 | { | |
6349 | perf_guest_cbs = cbs; | |
6350 | return 0; | |
6351 | } | |
6352 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6353 | ||
6354 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6355 | { | |
6356 | perf_guest_cbs = NULL; | |
6357 | return 0; | |
6358 | } | |
6359 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6360 | ||
4018994f JO |
6361 | static void |
6362 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6363 | struct pt_regs *regs, u64 mask) | |
6364 | { | |
6365 | int bit; | |
29dd3288 | 6366 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6367 | |
29dd3288 MS |
6368 | bitmap_from_u64(_mask, mask); |
6369 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6370 | u64 val; |
6371 | ||
6372 | val = perf_reg_value(regs, bit); | |
6373 | perf_output_put(handle, val); | |
6374 | } | |
6375 | } | |
6376 | ||
60e2364e | 6377 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
76a4efa8 | 6378 | struct pt_regs *regs) |
4018994f | 6379 | { |
88a7c26a AL |
6380 | if (user_mode(regs)) { |
6381 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6382 | regs_user->regs = regs; |
085ebfe9 | 6383 | } else if (!(current->flags & PF_KTHREAD)) { |
76a4efa8 | 6384 | perf_get_regs_user(regs_user, regs); |
2565711f PZ |
6385 | } else { |
6386 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6387 | regs_user->regs = NULL; | |
4018994f JO |
6388 | } |
6389 | } | |
6390 | ||
60e2364e SE |
6391 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6392 | struct pt_regs *regs) | |
6393 | { | |
6394 | regs_intr->regs = regs; | |
6395 | regs_intr->abi = perf_reg_abi(current); | |
6396 | } | |
6397 | ||
6398 | ||
c5ebcedb JO |
6399 | /* |
6400 | * Get remaining task size from user stack pointer. | |
6401 | * | |
6402 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6403 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6404 | * so using TASK_SIZE as limit. |
6405 | */ | |
6406 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6407 | { | |
6408 | unsigned long addr = perf_user_stack_pointer(regs); | |
6409 | ||
6410 | if (!addr || addr >= TASK_SIZE) | |
6411 | return 0; | |
6412 | ||
6413 | return TASK_SIZE - addr; | |
6414 | } | |
6415 | ||
6416 | static u16 | |
6417 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6418 | struct pt_regs *regs) | |
6419 | { | |
6420 | u64 task_size; | |
6421 | ||
6422 | /* No regs, no stack pointer, no dump. */ | |
6423 | if (!regs) | |
6424 | return 0; | |
6425 | ||
6426 | /* | |
6427 | * Check if we fit in with the requested stack size into the: | |
6428 | * - TASK_SIZE | |
6429 | * If we don't, we limit the size to the TASK_SIZE. | |
6430 | * | |
6431 | * - remaining sample size | |
6432 | * If we don't, we customize the stack size to | |
6433 | * fit in to the remaining sample size. | |
6434 | */ | |
6435 | ||
6436 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6437 | stack_size = min(stack_size, (u16) task_size); | |
6438 | ||
6439 | /* Current header size plus static size and dynamic size. */ | |
6440 | header_size += 2 * sizeof(u64); | |
6441 | ||
6442 | /* Do we fit in with the current stack dump size? */ | |
6443 | if ((u16) (header_size + stack_size) < header_size) { | |
6444 | /* | |
6445 | * If we overflow the maximum size for the sample, | |
6446 | * we customize the stack dump size to fit in. | |
6447 | */ | |
6448 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6449 | stack_size = round_up(stack_size, sizeof(u64)); | |
6450 | } | |
6451 | ||
6452 | return stack_size; | |
6453 | } | |
6454 | ||
6455 | static void | |
6456 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6457 | struct pt_regs *regs) | |
6458 | { | |
6459 | /* Case of a kernel thread, nothing to dump */ | |
6460 | if (!regs) { | |
6461 | u64 size = 0; | |
6462 | perf_output_put(handle, size); | |
6463 | } else { | |
6464 | unsigned long sp; | |
6465 | unsigned int rem; | |
6466 | u64 dyn_size; | |
02e18447 | 6467 | mm_segment_t fs; |
c5ebcedb JO |
6468 | |
6469 | /* | |
6470 | * We dump: | |
6471 | * static size | |
6472 | * - the size requested by user or the best one we can fit | |
6473 | * in to the sample max size | |
6474 | * data | |
6475 | * - user stack dump data | |
6476 | * dynamic size | |
6477 | * - the actual dumped size | |
6478 | */ | |
6479 | ||
6480 | /* Static size. */ | |
6481 | perf_output_put(handle, dump_size); | |
6482 | ||
6483 | /* Data. */ | |
6484 | sp = perf_user_stack_pointer(regs); | |
3d13f313 | 6485 | fs = force_uaccess_begin(); |
c5ebcedb | 6486 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
3d13f313 | 6487 | force_uaccess_end(fs); |
c5ebcedb JO |
6488 | dyn_size = dump_size - rem; |
6489 | ||
6490 | perf_output_skip(handle, rem); | |
6491 | ||
6492 | /* Dynamic size. */ | |
6493 | perf_output_put(handle, dyn_size); | |
6494 | } | |
6495 | } | |
6496 | ||
a4faf00d AS |
6497 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6498 | struct perf_sample_data *data, | |
6499 | size_t size) | |
6500 | { | |
6501 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6502 | struct perf_buffer *rb; |
a4faf00d AS |
6503 | |
6504 | data->aux_size = 0; | |
6505 | ||
6506 | if (!sampler) | |
6507 | goto out; | |
6508 | ||
6509 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6510 | goto out; | |
6511 | ||
6512 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6513 | goto out; | |
6514 | ||
6515 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6516 | if (!rb) | |
6517 | goto out; | |
6518 | ||
6519 | /* | |
6520 | * If this is an NMI hit inside sampling code, don't take | |
6521 | * the sample. See also perf_aux_sample_output(). | |
6522 | */ | |
6523 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6524 | data->aux_size = 0; | |
6525 | } else { | |
6526 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6527 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6528 | } | |
6529 | ring_buffer_put(rb); | |
6530 | ||
6531 | out: | |
6532 | return data->aux_size; | |
6533 | } | |
6534 | ||
56de4e8f | 6535 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6536 | struct perf_event *event, |
6537 | struct perf_output_handle *handle, | |
6538 | unsigned long size) | |
6539 | { | |
6540 | unsigned long flags; | |
6541 | long ret; | |
6542 | ||
6543 | /* | |
6544 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6545 | * paths. If we start calling them in NMI context, they may race with | |
6546 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6547 | * been stopped, which is why we're using a separate callback that | |
6548 | * doesn't change the event state. | |
6549 | * | |
6550 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6551 | */ | |
6552 | local_irq_save(flags); | |
6553 | /* | |
6554 | * Guard against NMI hits inside the critical section; | |
6555 | * see also perf_prepare_sample_aux(). | |
6556 | */ | |
6557 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6558 | barrier(); | |
6559 | ||
6560 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6561 | ||
6562 | barrier(); | |
6563 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6564 | local_irq_restore(flags); | |
6565 | ||
6566 | return ret; | |
6567 | } | |
6568 | ||
6569 | static void perf_aux_sample_output(struct perf_event *event, | |
6570 | struct perf_output_handle *handle, | |
6571 | struct perf_sample_data *data) | |
6572 | { | |
6573 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6574 | struct perf_buffer *rb; |
a4faf00d | 6575 | unsigned long pad; |
a4faf00d AS |
6576 | long size; |
6577 | ||
6578 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6579 | return; | |
6580 | ||
6581 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6582 | if (!rb) | |
6583 | return; | |
6584 | ||
6585 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6586 | ||
6587 | /* | |
6588 | * An error here means that perf_output_copy() failed (returned a | |
6589 | * non-zero surplus that it didn't copy), which in its current | |
6590 | * enlightened implementation is not possible. If that changes, we'd | |
6591 | * like to know. | |
6592 | */ | |
6593 | if (WARN_ON_ONCE(size < 0)) | |
6594 | goto out_put; | |
6595 | ||
6596 | /* | |
6597 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6598 | * perf_prepare_sample_aux(), so should not be more than that. | |
6599 | */ | |
6600 | pad = data->aux_size - size; | |
6601 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6602 | pad = 8; | |
6603 | ||
6604 | if (pad) { | |
6605 | u64 zero = 0; | |
6606 | perf_output_copy(handle, &zero, pad); | |
6607 | } | |
6608 | ||
6609 | out_put: | |
6610 | ring_buffer_put(rb); | |
6611 | } | |
6612 | ||
c980d109 ACM |
6613 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6614 | struct perf_sample_data *data, | |
6615 | struct perf_event *event) | |
6844c09d ACM |
6616 | { |
6617 | u64 sample_type = event->attr.sample_type; | |
6618 | ||
6619 | data->type = sample_type; | |
6620 | header->size += event->id_header_size; | |
6621 | ||
6622 | if (sample_type & PERF_SAMPLE_TID) { | |
6623 | /* namespace issues */ | |
6624 | data->tid_entry.pid = perf_event_pid(event, current); | |
6625 | data->tid_entry.tid = perf_event_tid(event, current); | |
6626 | } | |
6627 | ||
6628 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6629 | data->time = perf_event_clock(event); |
6844c09d | 6630 | |
ff3d527c | 6631 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6632 | data->id = primary_event_id(event); |
6633 | ||
6634 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6635 | data->stream_id = event->id; | |
6636 | ||
6637 | if (sample_type & PERF_SAMPLE_CPU) { | |
6638 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6639 | data->cpu_entry.reserved = 0; | |
6640 | } | |
6641 | } | |
6642 | ||
76369139 FW |
6643 | void perf_event_header__init_id(struct perf_event_header *header, |
6644 | struct perf_sample_data *data, | |
6645 | struct perf_event *event) | |
c980d109 ACM |
6646 | { |
6647 | if (event->attr.sample_id_all) | |
6648 | __perf_event_header__init_id(header, data, event); | |
6649 | } | |
6650 | ||
6651 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6652 | struct perf_sample_data *data) | |
6653 | { | |
6654 | u64 sample_type = data->type; | |
6655 | ||
6656 | if (sample_type & PERF_SAMPLE_TID) | |
6657 | perf_output_put(handle, data->tid_entry); | |
6658 | ||
6659 | if (sample_type & PERF_SAMPLE_TIME) | |
6660 | perf_output_put(handle, data->time); | |
6661 | ||
6662 | if (sample_type & PERF_SAMPLE_ID) | |
6663 | perf_output_put(handle, data->id); | |
6664 | ||
6665 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6666 | perf_output_put(handle, data->stream_id); | |
6667 | ||
6668 | if (sample_type & PERF_SAMPLE_CPU) | |
6669 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6670 | |
6671 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6672 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6673 | } |
6674 | ||
76369139 FW |
6675 | void perf_event__output_id_sample(struct perf_event *event, |
6676 | struct perf_output_handle *handle, | |
6677 | struct perf_sample_data *sample) | |
c980d109 ACM |
6678 | { |
6679 | if (event->attr.sample_id_all) | |
6680 | __perf_event__output_id_sample(handle, sample); | |
6681 | } | |
6682 | ||
3dab77fb | 6683 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6684 | struct perf_event *event, |
6685 | u64 enabled, u64 running) | |
3dab77fb | 6686 | { |
cdd6c482 | 6687 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6688 | u64 values[4]; |
6689 | int n = 0; | |
6690 | ||
b5e58793 | 6691 | values[n++] = perf_event_count(event); |
3dab77fb | 6692 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6693 | values[n++] = enabled + |
cdd6c482 | 6694 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6695 | } |
6696 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6697 | values[n++] = running + |
cdd6c482 | 6698 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6699 | } |
6700 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6701 | values[n++] = primary_event_id(event); |
3dab77fb | 6702 | |
76369139 | 6703 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6704 | } |
6705 | ||
3dab77fb | 6706 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6707 | struct perf_event *event, |
6708 | u64 enabled, u64 running) | |
3dab77fb | 6709 | { |
cdd6c482 IM |
6710 | struct perf_event *leader = event->group_leader, *sub; |
6711 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6712 | u64 values[5]; |
6713 | int n = 0; | |
6714 | ||
6715 | values[n++] = 1 + leader->nr_siblings; | |
6716 | ||
6717 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6718 | values[n++] = enabled; |
3dab77fb PZ |
6719 | |
6720 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6721 | values[n++] = running; |
3dab77fb | 6722 | |
9e5b127d PZ |
6723 | if ((leader != event) && |
6724 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6725 | leader->pmu->read(leader); |
6726 | ||
b5e58793 | 6727 | values[n++] = perf_event_count(leader); |
3dab77fb | 6728 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6729 | values[n++] = primary_event_id(leader); |
3dab77fb | 6730 | |
76369139 | 6731 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6732 | |
edb39592 | 6733 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6734 | n = 0; |
6735 | ||
6f5ab001 JO |
6736 | if ((sub != event) && |
6737 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6738 | sub->pmu->read(sub); |
6739 | ||
b5e58793 | 6740 | values[n++] = perf_event_count(sub); |
3dab77fb | 6741 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6742 | values[n++] = primary_event_id(sub); |
3dab77fb | 6743 | |
76369139 | 6744 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6745 | } |
6746 | } | |
6747 | ||
eed01528 SE |
6748 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6749 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6750 | ||
ba5213ae PZ |
6751 | /* |
6752 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6753 | * | |
6754 | * The problem is that its both hard and excessively expensive to iterate the | |
6755 | * child list, not to mention that its impossible to IPI the children running | |
6756 | * on another CPU, from interrupt/NMI context. | |
6757 | */ | |
3dab77fb | 6758 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6759 | struct perf_event *event) |
3dab77fb | 6760 | { |
e3f3541c | 6761 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6762 | u64 read_format = event->attr.read_format; |
6763 | ||
6764 | /* | |
6765 | * compute total_time_enabled, total_time_running | |
6766 | * based on snapshot values taken when the event | |
6767 | * was last scheduled in. | |
6768 | * | |
6769 | * we cannot simply called update_context_time() | |
6770 | * because of locking issue as we are called in | |
6771 | * NMI context | |
6772 | */ | |
c4794295 | 6773 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6774 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6775 | |
cdd6c482 | 6776 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6777 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6778 | else |
eed01528 | 6779 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6780 | } |
6781 | ||
bbfd5e4f KL |
6782 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6783 | { | |
6784 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6785 | } | |
6786 | ||
5622f295 MM |
6787 | void perf_output_sample(struct perf_output_handle *handle, |
6788 | struct perf_event_header *header, | |
6789 | struct perf_sample_data *data, | |
cdd6c482 | 6790 | struct perf_event *event) |
5622f295 MM |
6791 | { |
6792 | u64 sample_type = data->type; | |
6793 | ||
6794 | perf_output_put(handle, *header); | |
6795 | ||
ff3d527c AH |
6796 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6797 | perf_output_put(handle, data->id); | |
6798 | ||
5622f295 MM |
6799 | if (sample_type & PERF_SAMPLE_IP) |
6800 | perf_output_put(handle, data->ip); | |
6801 | ||
6802 | if (sample_type & PERF_SAMPLE_TID) | |
6803 | perf_output_put(handle, data->tid_entry); | |
6804 | ||
6805 | if (sample_type & PERF_SAMPLE_TIME) | |
6806 | perf_output_put(handle, data->time); | |
6807 | ||
6808 | if (sample_type & PERF_SAMPLE_ADDR) | |
6809 | perf_output_put(handle, data->addr); | |
6810 | ||
6811 | if (sample_type & PERF_SAMPLE_ID) | |
6812 | perf_output_put(handle, data->id); | |
6813 | ||
6814 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6815 | perf_output_put(handle, data->stream_id); | |
6816 | ||
6817 | if (sample_type & PERF_SAMPLE_CPU) | |
6818 | perf_output_put(handle, data->cpu_entry); | |
6819 | ||
6820 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6821 | perf_output_put(handle, data->period); | |
6822 | ||
6823 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6824 | perf_output_read(handle, event); |
5622f295 MM |
6825 | |
6826 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6827 | int size = 1; |
5622f295 | 6828 | |
99e818cc JO |
6829 | size += data->callchain->nr; |
6830 | size *= sizeof(u64); | |
6831 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6832 | } |
6833 | ||
6834 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6835 | struct perf_raw_record *raw = data->raw; |
6836 | ||
6837 | if (raw) { | |
6838 | struct perf_raw_frag *frag = &raw->frag; | |
6839 | ||
6840 | perf_output_put(handle, raw->size); | |
6841 | do { | |
6842 | if (frag->copy) { | |
6843 | __output_custom(handle, frag->copy, | |
6844 | frag->data, frag->size); | |
6845 | } else { | |
6846 | __output_copy(handle, frag->data, | |
6847 | frag->size); | |
6848 | } | |
6849 | if (perf_raw_frag_last(frag)) | |
6850 | break; | |
6851 | frag = frag->next; | |
6852 | } while (1); | |
6853 | if (frag->pad) | |
6854 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6855 | } else { |
6856 | struct { | |
6857 | u32 size; | |
6858 | u32 data; | |
6859 | } raw = { | |
6860 | .size = sizeof(u32), | |
6861 | .data = 0, | |
6862 | }; | |
6863 | perf_output_put(handle, raw); | |
6864 | } | |
6865 | } | |
a7ac67ea | 6866 | |
bce38cd5 SE |
6867 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6868 | if (data->br_stack) { | |
6869 | size_t size; | |
6870 | ||
6871 | size = data->br_stack->nr | |
6872 | * sizeof(struct perf_branch_entry); | |
6873 | ||
6874 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6875 | if (perf_sample_save_hw_index(event)) |
6876 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6877 | perf_output_copy(handle, data->br_stack->entries, size); |
6878 | } else { | |
6879 | /* | |
6880 | * we always store at least the value of nr | |
6881 | */ | |
6882 | u64 nr = 0; | |
6883 | perf_output_put(handle, nr); | |
6884 | } | |
6885 | } | |
4018994f JO |
6886 | |
6887 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6888 | u64 abi = data->regs_user.abi; | |
6889 | ||
6890 | /* | |
6891 | * If there are no regs to dump, notice it through | |
6892 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6893 | */ | |
6894 | perf_output_put(handle, abi); | |
6895 | ||
6896 | if (abi) { | |
6897 | u64 mask = event->attr.sample_regs_user; | |
6898 | perf_output_sample_regs(handle, | |
6899 | data->regs_user.regs, | |
6900 | mask); | |
6901 | } | |
6902 | } | |
c5ebcedb | 6903 | |
a5cdd40c | 6904 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6905 | perf_output_sample_ustack(handle, |
6906 | data->stack_user_size, | |
6907 | data->regs_user.regs); | |
a5cdd40c | 6908 | } |
c3feedf2 AK |
6909 | |
6910 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6911 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6912 | |
6913 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6914 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6915 | |
fdfbbd07 AK |
6916 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6917 | perf_output_put(handle, data->txn); | |
6918 | ||
60e2364e SE |
6919 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6920 | u64 abi = data->regs_intr.abi; | |
6921 | /* | |
6922 | * If there are no regs to dump, notice it through | |
6923 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6924 | */ | |
6925 | perf_output_put(handle, abi); | |
6926 | ||
6927 | if (abi) { | |
6928 | u64 mask = event->attr.sample_regs_intr; | |
6929 | ||
6930 | perf_output_sample_regs(handle, | |
6931 | data->regs_intr.regs, | |
6932 | mask); | |
6933 | } | |
6934 | } | |
6935 | ||
fc7ce9c7 KL |
6936 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6937 | perf_output_put(handle, data->phys_addr); | |
6938 | ||
6546b19f NK |
6939 | if (sample_type & PERF_SAMPLE_CGROUP) |
6940 | perf_output_put(handle, data->cgroup); | |
6941 | ||
8d97e718 KL |
6942 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) |
6943 | perf_output_put(handle, data->data_page_size); | |
6944 | ||
995f088e SE |
6945 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
6946 | perf_output_put(handle, data->code_page_size); | |
6947 | ||
a4faf00d AS |
6948 | if (sample_type & PERF_SAMPLE_AUX) { |
6949 | perf_output_put(handle, data->aux_size); | |
6950 | ||
6951 | if (data->aux_size) | |
6952 | perf_aux_sample_output(event, handle, data); | |
6953 | } | |
6954 | ||
a5cdd40c PZ |
6955 | if (!event->attr.watermark) { |
6956 | int wakeup_events = event->attr.wakeup_events; | |
6957 | ||
6958 | if (wakeup_events) { | |
56de4e8f | 6959 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6960 | int events = local_inc_return(&rb->events); |
6961 | ||
6962 | if (events >= wakeup_events) { | |
6963 | local_sub(wakeup_events, &rb->events); | |
6964 | local_inc(&rb->wakeup); | |
6965 | } | |
6966 | } | |
6967 | } | |
5622f295 MM |
6968 | } |
6969 | ||
fc7ce9c7 KL |
6970 | static u64 perf_virt_to_phys(u64 virt) |
6971 | { | |
6972 | u64 phys_addr = 0; | |
6973 | struct page *p = NULL; | |
6974 | ||
6975 | if (!virt) | |
6976 | return 0; | |
6977 | ||
6978 | if (virt >= TASK_SIZE) { | |
6979 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6980 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6981 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6982 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6983 | } else { | |
6984 | /* | |
6985 | * Walking the pages tables for user address. | |
6986 | * Interrupts are disabled, so it prevents any tear down | |
6987 | * of the page tables. | |
dadbb612 | 6988 | * Try IRQ-safe get_user_page_fast_only first. |
fc7ce9c7 KL |
6989 | * If failed, leave phys_addr as 0. |
6990 | */ | |
d3296fb3 JO |
6991 | if (current->mm != NULL) { |
6992 | pagefault_disable(); | |
dadbb612 | 6993 | if (get_user_page_fast_only(virt, 0, &p)) |
d3296fb3 JO |
6994 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; |
6995 | pagefault_enable(); | |
6996 | } | |
fc7ce9c7 KL |
6997 | |
6998 | if (p) | |
6999 | put_page(p); | |
7000 | } | |
7001 | ||
7002 | return phys_addr; | |
7003 | } | |
7004 | ||
8d97e718 | 7005 | /* |
8af26be0 | 7006 | * Return the pagetable size of a given virtual address. |
8d97e718 | 7007 | */ |
8af26be0 | 7008 | static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) |
8d97e718 | 7009 | { |
8af26be0 | 7010 | u64 size = 0; |
8d97e718 | 7011 | |
8af26be0 PZ |
7012 | #ifdef CONFIG_HAVE_FAST_GUP |
7013 | pgd_t *pgdp, pgd; | |
7014 | p4d_t *p4dp, p4d; | |
7015 | pud_t *pudp, pud; | |
7016 | pmd_t *pmdp, pmd; | |
7017 | pte_t *ptep, pte; | |
8d97e718 | 7018 | |
8af26be0 PZ |
7019 | pgdp = pgd_offset(mm, addr); |
7020 | pgd = READ_ONCE(*pgdp); | |
7021 | if (pgd_none(pgd)) | |
8d97e718 KL |
7022 | return 0; |
7023 | ||
8af26be0 PZ |
7024 | if (pgd_leaf(pgd)) |
7025 | return pgd_leaf_size(pgd); | |
8d97e718 | 7026 | |
8af26be0 PZ |
7027 | p4dp = p4d_offset_lockless(pgdp, pgd, addr); |
7028 | p4d = READ_ONCE(*p4dp); | |
7029 | if (!p4d_present(p4d)) | |
8d97e718 KL |
7030 | return 0; |
7031 | ||
8af26be0 PZ |
7032 | if (p4d_leaf(p4d)) |
7033 | return p4d_leaf_size(p4d); | |
8d97e718 | 7034 | |
8af26be0 PZ |
7035 | pudp = pud_offset_lockless(p4dp, p4d, addr); |
7036 | pud = READ_ONCE(*pudp); | |
7037 | if (!pud_present(pud)) | |
8d97e718 KL |
7038 | return 0; |
7039 | ||
8af26be0 PZ |
7040 | if (pud_leaf(pud)) |
7041 | return pud_leaf_size(pud); | |
8d97e718 | 7042 | |
8af26be0 PZ |
7043 | pmdp = pmd_offset_lockless(pudp, pud, addr); |
7044 | pmd = READ_ONCE(*pmdp); | |
7045 | if (!pmd_present(pmd)) | |
8d97e718 | 7046 | return 0; |
8d97e718 | 7047 | |
8af26be0 PZ |
7048 | if (pmd_leaf(pmd)) |
7049 | return pmd_leaf_size(pmd); | |
51b646b2 | 7050 | |
8af26be0 PZ |
7051 | ptep = pte_offset_map(&pmd, addr); |
7052 | pte = ptep_get_lockless(ptep); | |
7053 | if (pte_present(pte)) | |
7054 | size = pte_leaf_size(pte); | |
7055 | pte_unmap(ptep); | |
7056 | #endif /* CONFIG_HAVE_FAST_GUP */ | |
8d97e718 | 7057 | |
8af26be0 | 7058 | return size; |
8d97e718 KL |
7059 | } |
7060 | ||
8d97e718 KL |
7061 | static u64 perf_get_page_size(unsigned long addr) |
7062 | { | |
7063 | struct mm_struct *mm; | |
7064 | unsigned long flags; | |
7065 | u64 size; | |
7066 | ||
7067 | if (!addr) | |
7068 | return 0; | |
7069 | ||
7070 | /* | |
7071 | * Software page-table walkers must disable IRQs, | |
7072 | * which prevents any tear down of the page tables. | |
7073 | */ | |
7074 | local_irq_save(flags); | |
7075 | ||
7076 | mm = current->mm; | |
7077 | if (!mm) { | |
7078 | /* | |
7079 | * For kernel threads and the like, use init_mm so that | |
7080 | * we can find kernel memory. | |
7081 | */ | |
7082 | mm = &init_mm; | |
7083 | } | |
7084 | ||
8af26be0 | 7085 | size = perf_get_pgtable_size(mm, addr); |
8d97e718 KL |
7086 | |
7087 | local_irq_restore(flags); | |
7088 | ||
7089 | return size; | |
7090 | } | |
7091 | ||
99e818cc JO |
7092 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
7093 | ||
6cbc304f | 7094 | struct perf_callchain_entry * |
8cf7e0e2 JO |
7095 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
7096 | { | |
7097 | bool kernel = !event->attr.exclude_callchain_kernel; | |
7098 | bool user = !event->attr.exclude_callchain_user; | |
7099 | /* Disallow cross-task user callchains. */ | |
7100 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
7101 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 7102 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
7103 | |
7104 | if (!kernel && !user) | |
99e818cc | 7105 | return &__empty_callchain; |
8cf7e0e2 | 7106 | |
99e818cc JO |
7107 | callchain = get_perf_callchain(regs, 0, kernel, user, |
7108 | max_stack, crosstask, true); | |
7109 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
7110 | } |
7111 | ||
5622f295 MM |
7112 | void perf_prepare_sample(struct perf_event_header *header, |
7113 | struct perf_sample_data *data, | |
cdd6c482 | 7114 | struct perf_event *event, |
5622f295 | 7115 | struct pt_regs *regs) |
7b732a75 | 7116 | { |
cdd6c482 | 7117 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 7118 | |
cdd6c482 | 7119 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 7120 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
7121 | |
7122 | header->misc = 0; | |
7123 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 7124 | |
c980d109 | 7125 | __perf_event_header__init_id(header, data, event); |
6844c09d | 7126 | |
995f088e | 7127 | if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE)) |
5622f295 MM |
7128 | data->ip = perf_instruction_pointer(regs); |
7129 | ||
b23f3325 | 7130 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 7131 | int size = 1; |
394ee076 | 7132 | |
6cbc304f PZ |
7133 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
7134 | data->callchain = perf_callchain(event, regs); | |
7135 | ||
99e818cc | 7136 | size += data->callchain->nr; |
5622f295 MM |
7137 | |
7138 | header->size += size * sizeof(u64); | |
394ee076 PZ |
7139 | } |
7140 | ||
3a43ce68 | 7141 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
7142 | struct perf_raw_record *raw = data->raw; |
7143 | int size; | |
7144 | ||
7145 | if (raw) { | |
7146 | struct perf_raw_frag *frag = &raw->frag; | |
7147 | u32 sum = 0; | |
7148 | ||
7149 | do { | |
7150 | sum += frag->size; | |
7151 | if (perf_raw_frag_last(frag)) | |
7152 | break; | |
7153 | frag = frag->next; | |
7154 | } while (1); | |
7155 | ||
7156 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
7157 | raw->size = size - sizeof(u32); | |
7158 | frag->pad = raw->size - sum; | |
7159 | } else { | |
7160 | size = sizeof(u64); | |
7161 | } | |
a044560c | 7162 | |
7e3f977e | 7163 | header->size += size; |
7f453c24 | 7164 | } |
bce38cd5 SE |
7165 | |
7166 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7167 | int size = sizeof(u64); /* nr */ | |
7168 | if (data->br_stack) { | |
bbfd5e4f KL |
7169 | if (perf_sample_save_hw_index(event)) |
7170 | size += sizeof(u64); | |
7171 | ||
bce38cd5 SE |
7172 | size += data->br_stack->nr |
7173 | * sizeof(struct perf_branch_entry); | |
7174 | } | |
7175 | header->size += size; | |
7176 | } | |
4018994f | 7177 | |
2565711f | 7178 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
76a4efa8 | 7179 | perf_sample_regs_user(&data->regs_user, regs); |
2565711f | 7180 | |
4018994f JO |
7181 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7182 | /* regs dump ABI info */ | |
7183 | int size = sizeof(u64); | |
7184 | ||
4018994f JO |
7185 | if (data->regs_user.regs) { |
7186 | u64 mask = event->attr.sample_regs_user; | |
7187 | size += hweight64(mask) * sizeof(u64); | |
7188 | } | |
7189 | ||
7190 | header->size += size; | |
7191 | } | |
c5ebcedb JO |
7192 | |
7193 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7194 | /* | |
9f014e3a | 7195 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7196 | * processed as the last one or have additional check added |
7197 | * in case new sample type is added, because we could eat | |
7198 | * up the rest of the sample size. | |
7199 | */ | |
c5ebcedb JO |
7200 | u16 stack_size = event->attr.sample_stack_user; |
7201 | u16 size = sizeof(u64); | |
7202 | ||
c5ebcedb | 7203 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7204 | data->regs_user.regs); |
c5ebcedb JO |
7205 | |
7206 | /* | |
7207 | * If there is something to dump, add space for the dump | |
7208 | * itself and for the field that tells the dynamic size, | |
7209 | * which is how many have been actually dumped. | |
7210 | */ | |
7211 | if (stack_size) | |
7212 | size += sizeof(u64) + stack_size; | |
7213 | ||
7214 | data->stack_user_size = stack_size; | |
7215 | header->size += size; | |
7216 | } | |
60e2364e SE |
7217 | |
7218 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7219 | /* regs dump ABI info */ | |
7220 | int size = sizeof(u64); | |
7221 | ||
7222 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7223 | ||
7224 | if (data->regs_intr.regs) { | |
7225 | u64 mask = event->attr.sample_regs_intr; | |
7226 | ||
7227 | size += hweight64(mask) * sizeof(u64); | |
7228 | } | |
7229 | ||
7230 | header->size += size; | |
7231 | } | |
fc7ce9c7 KL |
7232 | |
7233 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7234 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7235 | |
6546b19f NK |
7236 | #ifdef CONFIG_CGROUP_PERF |
7237 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7238 | struct cgroup *cgrp; | |
7239 | ||
7240 | /* protected by RCU */ | |
7241 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7242 | data->cgroup = cgroup_id(cgrp); | |
7243 | } | |
7244 | #endif | |
7245 | ||
8d97e718 KL |
7246 | /* |
7247 | * PERF_DATA_PAGE_SIZE requires PERF_SAMPLE_ADDR. If the user doesn't | |
7248 | * require PERF_SAMPLE_ADDR, kernel implicitly retrieve the data->addr, | |
7249 | * but the value will not dump to the userspace. | |
7250 | */ | |
7251 | if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) | |
7252 | data->data_page_size = perf_get_page_size(data->addr); | |
7253 | ||
995f088e SE |
7254 | if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) |
7255 | data->code_page_size = perf_get_page_size(data->ip); | |
7256 | ||
a4faf00d AS |
7257 | if (sample_type & PERF_SAMPLE_AUX) { |
7258 | u64 size; | |
7259 | ||
7260 | header->size += sizeof(u64); /* size */ | |
7261 | ||
7262 | /* | |
7263 | * Given the 16bit nature of header::size, an AUX sample can | |
7264 | * easily overflow it, what with all the preceding sample bits. | |
7265 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7266 | * per sample in total (rounded down to 8 byte boundary). | |
7267 | */ | |
7268 | size = min_t(size_t, U16_MAX - header->size, | |
7269 | event->attr.aux_sample_size); | |
7270 | size = rounddown(size, 8); | |
7271 | size = perf_prepare_sample_aux(event, data, size); | |
7272 | ||
7273 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7274 | header->size += size; | |
7275 | } | |
7276 | /* | |
7277 | * If you're adding more sample types here, you likely need to do | |
7278 | * something about the overflowing header::size, like repurpose the | |
7279 | * lowest 3 bits of size, which should be always zero at the moment. | |
7280 | * This raises a more important question, do we really need 512k sized | |
7281 | * samples and why, so good argumentation is in order for whatever you | |
7282 | * do here next. | |
7283 | */ | |
7284 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7285 | } |
7f453c24 | 7286 | |
56201969 | 7287 | static __always_inline int |
9ecda41a WN |
7288 | __perf_event_output(struct perf_event *event, |
7289 | struct perf_sample_data *data, | |
7290 | struct pt_regs *regs, | |
7291 | int (*output_begin)(struct perf_output_handle *, | |
267fb273 | 7292 | struct perf_sample_data *, |
9ecda41a WN |
7293 | struct perf_event *, |
7294 | unsigned int)) | |
5622f295 MM |
7295 | { |
7296 | struct perf_output_handle handle; | |
7297 | struct perf_event_header header; | |
56201969 | 7298 | int err; |
689802b2 | 7299 | |
927c7a9e FW |
7300 | /* protect the callchain buffers */ |
7301 | rcu_read_lock(); | |
7302 | ||
cdd6c482 | 7303 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7304 | |
267fb273 | 7305 | err = output_begin(&handle, data, event, header.size); |
56201969 | 7306 | if (err) |
927c7a9e | 7307 | goto exit; |
0322cd6e | 7308 | |
cdd6c482 | 7309 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7310 | |
8a057d84 | 7311 | perf_output_end(&handle); |
927c7a9e FW |
7312 | |
7313 | exit: | |
7314 | rcu_read_unlock(); | |
56201969 | 7315 | return err; |
0322cd6e PZ |
7316 | } |
7317 | ||
9ecda41a WN |
7318 | void |
7319 | perf_event_output_forward(struct perf_event *event, | |
7320 | struct perf_sample_data *data, | |
7321 | struct pt_regs *regs) | |
7322 | { | |
7323 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7324 | } | |
7325 | ||
7326 | void | |
7327 | perf_event_output_backward(struct perf_event *event, | |
7328 | struct perf_sample_data *data, | |
7329 | struct pt_regs *regs) | |
7330 | { | |
7331 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7332 | } | |
7333 | ||
56201969 | 7334 | int |
9ecda41a WN |
7335 | perf_event_output(struct perf_event *event, |
7336 | struct perf_sample_data *data, | |
7337 | struct pt_regs *regs) | |
7338 | { | |
56201969 | 7339 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7340 | } |
7341 | ||
38b200d6 | 7342 | /* |
cdd6c482 | 7343 | * read event_id |
38b200d6 PZ |
7344 | */ |
7345 | ||
7346 | struct perf_read_event { | |
7347 | struct perf_event_header header; | |
7348 | ||
7349 | u32 pid; | |
7350 | u32 tid; | |
38b200d6 PZ |
7351 | }; |
7352 | ||
7353 | static void | |
cdd6c482 | 7354 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7355 | struct task_struct *task) |
7356 | { | |
7357 | struct perf_output_handle handle; | |
c980d109 | 7358 | struct perf_sample_data sample; |
dfc65094 | 7359 | struct perf_read_event read_event = { |
38b200d6 | 7360 | .header = { |
cdd6c482 | 7361 | .type = PERF_RECORD_READ, |
38b200d6 | 7362 | .misc = 0, |
c320c7b7 | 7363 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7364 | }, |
cdd6c482 IM |
7365 | .pid = perf_event_pid(event, task), |
7366 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7367 | }; |
3dab77fb | 7368 | int ret; |
38b200d6 | 7369 | |
c980d109 | 7370 | perf_event_header__init_id(&read_event.header, &sample, event); |
267fb273 | 7371 | ret = perf_output_begin(&handle, &sample, event, read_event.header.size); |
38b200d6 PZ |
7372 | if (ret) |
7373 | return; | |
7374 | ||
dfc65094 | 7375 | perf_output_put(&handle, read_event); |
cdd6c482 | 7376 | perf_output_read(&handle, event); |
c980d109 | 7377 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7378 | |
38b200d6 PZ |
7379 | perf_output_end(&handle); |
7380 | } | |
7381 | ||
aab5b71e | 7382 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7383 | |
7384 | static void | |
aab5b71e PZ |
7385 | perf_iterate_ctx(struct perf_event_context *ctx, |
7386 | perf_iterate_f output, | |
b73e4fef | 7387 | void *data, bool all) |
52d857a8 JO |
7388 | { |
7389 | struct perf_event *event; | |
7390 | ||
7391 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7392 | if (!all) { |
7393 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7394 | continue; | |
7395 | if (!event_filter_match(event)) | |
7396 | continue; | |
7397 | } | |
7398 | ||
67516844 | 7399 | output(event, data); |
52d857a8 JO |
7400 | } |
7401 | } | |
7402 | ||
aab5b71e | 7403 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7404 | { |
7405 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7406 | struct perf_event *event; | |
7407 | ||
7408 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7409 | /* |
7410 | * Skip events that are not fully formed yet; ensure that | |
7411 | * if we observe event->ctx, both event and ctx will be | |
7412 | * complete enough. See perf_install_in_context(). | |
7413 | */ | |
7414 | if (!smp_load_acquire(&event->ctx)) | |
7415 | continue; | |
7416 | ||
f2fb6bef KL |
7417 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7418 | continue; | |
7419 | if (!event_filter_match(event)) | |
7420 | continue; | |
7421 | output(event, data); | |
7422 | } | |
7423 | } | |
7424 | ||
aab5b71e PZ |
7425 | /* |
7426 | * Iterate all events that need to receive side-band events. | |
7427 | * | |
7428 | * For new callers; ensure that account_pmu_sb_event() includes | |
7429 | * your event, otherwise it might not get delivered. | |
7430 | */ | |
52d857a8 | 7431 | static void |
aab5b71e | 7432 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7433 | struct perf_event_context *task_ctx) |
7434 | { | |
52d857a8 | 7435 | struct perf_event_context *ctx; |
52d857a8 JO |
7436 | int ctxn; |
7437 | ||
aab5b71e PZ |
7438 | rcu_read_lock(); |
7439 | preempt_disable(); | |
7440 | ||
4e93ad60 | 7441 | /* |
aab5b71e PZ |
7442 | * If we have task_ctx != NULL we only notify the task context itself. |
7443 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7444 | * context. |
7445 | */ | |
7446 | if (task_ctx) { | |
aab5b71e PZ |
7447 | perf_iterate_ctx(task_ctx, output, data, false); |
7448 | goto done; | |
4e93ad60 JO |
7449 | } |
7450 | ||
aab5b71e | 7451 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7452 | |
7453 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7454 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7455 | if (ctx) | |
aab5b71e | 7456 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7457 | } |
aab5b71e | 7458 | done: |
f2fb6bef | 7459 | preempt_enable(); |
52d857a8 | 7460 | rcu_read_unlock(); |
95ff4ca2 AS |
7461 | } |
7462 | ||
375637bc AS |
7463 | /* |
7464 | * Clear all file-based filters at exec, they'll have to be | |
7465 | * re-instated when/if these objects are mmapped again. | |
7466 | */ | |
7467 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7468 | { | |
7469 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7470 | struct perf_addr_filter *filter; | |
7471 | unsigned int restart = 0, count = 0; | |
7472 | unsigned long flags; | |
7473 | ||
7474 | if (!has_addr_filter(event)) | |
7475 | return; | |
7476 | ||
7477 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7478 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7479 | if (filter->path.dentry) { |
c60f83b8 AS |
7480 | event->addr_filter_ranges[count].start = 0; |
7481 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7482 | restart++; |
7483 | } | |
7484 | ||
7485 | count++; | |
7486 | } | |
7487 | ||
7488 | if (restart) | |
7489 | event->addr_filters_gen++; | |
7490 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7491 | ||
7492 | if (restart) | |
767ae086 | 7493 | perf_event_stop(event, 1); |
375637bc AS |
7494 | } |
7495 | ||
7496 | void perf_event_exec(void) | |
7497 | { | |
7498 | struct perf_event_context *ctx; | |
7499 | int ctxn; | |
7500 | ||
7501 | rcu_read_lock(); | |
7502 | for_each_task_context_nr(ctxn) { | |
7503 | ctx = current->perf_event_ctxp[ctxn]; | |
7504 | if (!ctx) | |
7505 | continue; | |
7506 | ||
7507 | perf_event_enable_on_exec(ctxn); | |
7508 | ||
aab5b71e | 7509 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7510 | true); |
7511 | } | |
7512 | rcu_read_unlock(); | |
7513 | } | |
7514 | ||
95ff4ca2 | 7515 | struct remote_output { |
56de4e8f | 7516 | struct perf_buffer *rb; |
95ff4ca2 AS |
7517 | int err; |
7518 | }; | |
7519 | ||
7520 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7521 | { | |
7522 | struct perf_event *parent = event->parent; | |
7523 | struct remote_output *ro = data; | |
56de4e8f | 7524 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7525 | struct stop_event_data sd = { |
7526 | .event = event, | |
7527 | }; | |
95ff4ca2 AS |
7528 | |
7529 | if (!has_aux(event)) | |
7530 | return; | |
7531 | ||
7532 | if (!parent) | |
7533 | parent = event; | |
7534 | ||
7535 | /* | |
7536 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7537 | * ring-buffer, but it will be the child that's actually using it. |
7538 | * | |
7539 | * We are using event::rb to determine if the event should be stopped, | |
7540 | * however this may race with ring_buffer_attach() (through set_output), | |
7541 | * which will make us skip the event that actually needs to be stopped. | |
7542 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7543 | * its rb pointer. | |
95ff4ca2 AS |
7544 | */ |
7545 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7546 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7547 | } |
7548 | ||
7549 | static int __perf_pmu_output_stop(void *info) | |
7550 | { | |
7551 | struct perf_event *event = info; | |
f3a519e4 | 7552 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7553 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7554 | struct remote_output ro = { |
7555 | .rb = event->rb, | |
7556 | }; | |
7557 | ||
7558 | rcu_read_lock(); | |
aab5b71e | 7559 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7560 | if (cpuctx->task_ctx) |
aab5b71e | 7561 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7562 | &ro, false); |
95ff4ca2 AS |
7563 | rcu_read_unlock(); |
7564 | ||
7565 | return ro.err; | |
7566 | } | |
7567 | ||
7568 | static void perf_pmu_output_stop(struct perf_event *event) | |
7569 | { | |
7570 | struct perf_event *iter; | |
7571 | int err, cpu; | |
7572 | ||
7573 | restart: | |
7574 | rcu_read_lock(); | |
7575 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7576 | /* | |
7577 | * For per-CPU events, we need to make sure that neither they | |
7578 | * nor their children are running; for cpu==-1 events it's | |
7579 | * sufficient to stop the event itself if it's active, since | |
7580 | * it can't have children. | |
7581 | */ | |
7582 | cpu = iter->cpu; | |
7583 | if (cpu == -1) | |
7584 | cpu = READ_ONCE(iter->oncpu); | |
7585 | ||
7586 | if (cpu == -1) | |
7587 | continue; | |
7588 | ||
7589 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7590 | if (err == -EAGAIN) { | |
7591 | rcu_read_unlock(); | |
7592 | goto restart; | |
7593 | } | |
7594 | } | |
7595 | rcu_read_unlock(); | |
52d857a8 JO |
7596 | } |
7597 | ||
60313ebe | 7598 | /* |
9f498cc5 PZ |
7599 | * task tracking -- fork/exit |
7600 | * | |
13d7a241 | 7601 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7602 | */ |
7603 | ||
9f498cc5 | 7604 | struct perf_task_event { |
3a80b4a3 | 7605 | struct task_struct *task; |
cdd6c482 | 7606 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7607 | |
7608 | struct { | |
7609 | struct perf_event_header header; | |
7610 | ||
7611 | u32 pid; | |
7612 | u32 ppid; | |
9f498cc5 PZ |
7613 | u32 tid; |
7614 | u32 ptid; | |
393b2ad8 | 7615 | u64 time; |
cdd6c482 | 7616 | } event_id; |
60313ebe PZ |
7617 | }; |
7618 | ||
67516844 JO |
7619 | static int perf_event_task_match(struct perf_event *event) |
7620 | { | |
13d7a241 SE |
7621 | return event->attr.comm || event->attr.mmap || |
7622 | event->attr.mmap2 || event->attr.mmap_data || | |
7623 | event->attr.task; | |
67516844 JO |
7624 | } |
7625 | ||
cdd6c482 | 7626 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7627 | void *data) |
60313ebe | 7628 | { |
52d857a8 | 7629 | struct perf_task_event *task_event = data; |
60313ebe | 7630 | struct perf_output_handle handle; |
c980d109 | 7631 | struct perf_sample_data sample; |
9f498cc5 | 7632 | struct task_struct *task = task_event->task; |
c980d109 | 7633 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7634 | |
67516844 JO |
7635 | if (!perf_event_task_match(event)) |
7636 | return; | |
7637 | ||
c980d109 | 7638 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7639 | |
267fb273 | 7640 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7641 | task_event->event_id.header.size); |
ef60777c | 7642 | if (ret) |
c980d109 | 7643 | goto out; |
60313ebe | 7644 | |
cdd6c482 | 7645 | task_event->event_id.pid = perf_event_pid(event, task); |
cdd6c482 | 7646 | task_event->event_id.tid = perf_event_tid(event, task); |
f3bed55e IR |
7647 | |
7648 | if (task_event->event_id.header.type == PERF_RECORD_EXIT) { | |
7649 | task_event->event_id.ppid = perf_event_pid(event, | |
7650 | task->real_parent); | |
7651 | task_event->event_id.ptid = perf_event_pid(event, | |
7652 | task->real_parent); | |
7653 | } else { /* PERF_RECORD_FORK */ | |
7654 | task_event->event_id.ppid = perf_event_pid(event, current); | |
7655 | task_event->event_id.ptid = perf_event_tid(event, current); | |
7656 | } | |
9f498cc5 | 7657 | |
34f43927 PZ |
7658 | task_event->event_id.time = perf_event_clock(event); |
7659 | ||
cdd6c482 | 7660 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7661 | |
c980d109 ACM |
7662 | perf_event__output_id_sample(event, &handle, &sample); |
7663 | ||
60313ebe | 7664 | perf_output_end(&handle); |
c980d109 ACM |
7665 | out: |
7666 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7667 | } |
7668 | ||
cdd6c482 IM |
7669 | static void perf_event_task(struct task_struct *task, |
7670 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7671 | int new) |
60313ebe | 7672 | { |
9f498cc5 | 7673 | struct perf_task_event task_event; |
60313ebe | 7674 | |
cdd6c482 IM |
7675 | if (!atomic_read(&nr_comm_events) && |
7676 | !atomic_read(&nr_mmap_events) && | |
7677 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7678 | return; |
7679 | ||
9f498cc5 | 7680 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7681 | .task = task, |
7682 | .task_ctx = task_ctx, | |
cdd6c482 | 7683 | .event_id = { |
60313ebe | 7684 | .header = { |
cdd6c482 | 7685 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7686 | .misc = 0, |
cdd6c482 | 7687 | .size = sizeof(task_event.event_id), |
60313ebe | 7688 | }, |
573402db PZ |
7689 | /* .pid */ |
7690 | /* .ppid */ | |
9f498cc5 PZ |
7691 | /* .tid */ |
7692 | /* .ptid */ | |
34f43927 | 7693 | /* .time */ |
60313ebe PZ |
7694 | }, |
7695 | }; | |
7696 | ||
aab5b71e | 7697 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7698 | &task_event, |
7699 | task_ctx); | |
9f498cc5 PZ |
7700 | } |
7701 | ||
cdd6c482 | 7702 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7703 | { |
cdd6c482 | 7704 | perf_event_task(task, NULL, 1); |
e4222673 | 7705 | perf_event_namespaces(task); |
60313ebe PZ |
7706 | } |
7707 | ||
8d1b2d93 PZ |
7708 | /* |
7709 | * comm tracking | |
7710 | */ | |
7711 | ||
7712 | struct perf_comm_event { | |
22a4f650 IM |
7713 | struct task_struct *task; |
7714 | char *comm; | |
8d1b2d93 PZ |
7715 | int comm_size; |
7716 | ||
7717 | struct { | |
7718 | struct perf_event_header header; | |
7719 | ||
7720 | u32 pid; | |
7721 | u32 tid; | |
cdd6c482 | 7722 | } event_id; |
8d1b2d93 PZ |
7723 | }; |
7724 | ||
67516844 JO |
7725 | static int perf_event_comm_match(struct perf_event *event) |
7726 | { | |
7727 | return event->attr.comm; | |
7728 | } | |
7729 | ||
cdd6c482 | 7730 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7731 | void *data) |
8d1b2d93 | 7732 | { |
52d857a8 | 7733 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7734 | struct perf_output_handle handle; |
c980d109 | 7735 | struct perf_sample_data sample; |
cdd6c482 | 7736 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7737 | int ret; |
7738 | ||
67516844 JO |
7739 | if (!perf_event_comm_match(event)) |
7740 | return; | |
7741 | ||
c980d109 | 7742 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
267fb273 | 7743 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 7744 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7745 | |
7746 | if (ret) | |
c980d109 | 7747 | goto out; |
8d1b2d93 | 7748 | |
cdd6c482 IM |
7749 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7750 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7751 | |
cdd6c482 | 7752 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7753 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7754 | comm_event->comm_size); |
c980d109 ACM |
7755 | |
7756 | perf_event__output_id_sample(event, &handle, &sample); | |
7757 | ||
8d1b2d93 | 7758 | perf_output_end(&handle); |
c980d109 ACM |
7759 | out: |
7760 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7761 | } |
7762 | ||
cdd6c482 | 7763 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7764 | { |
413ee3b4 | 7765 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7766 | unsigned int size; |
8d1b2d93 | 7767 | |
413ee3b4 | 7768 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7769 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7770 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7771 | |
7772 | comm_event->comm = comm; | |
7773 | comm_event->comm_size = size; | |
7774 | ||
cdd6c482 | 7775 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7776 | |
aab5b71e | 7777 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7778 | comm_event, |
7779 | NULL); | |
8d1b2d93 PZ |
7780 | } |
7781 | ||
82b89778 | 7782 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7783 | { |
9ee318a7 PZ |
7784 | struct perf_comm_event comm_event; |
7785 | ||
cdd6c482 | 7786 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7787 | return; |
a63eaf34 | 7788 | |
9ee318a7 | 7789 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7790 | .task = task, |
573402db PZ |
7791 | /* .comm */ |
7792 | /* .comm_size */ | |
cdd6c482 | 7793 | .event_id = { |
573402db | 7794 | .header = { |
cdd6c482 | 7795 | .type = PERF_RECORD_COMM, |
82b89778 | 7796 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7797 | /* .size */ |
7798 | }, | |
7799 | /* .pid */ | |
7800 | /* .tid */ | |
8d1b2d93 PZ |
7801 | }, |
7802 | }; | |
7803 | ||
cdd6c482 | 7804 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7805 | } |
7806 | ||
e4222673 HB |
7807 | /* |
7808 | * namespaces tracking | |
7809 | */ | |
7810 | ||
7811 | struct perf_namespaces_event { | |
7812 | struct task_struct *task; | |
7813 | ||
7814 | struct { | |
7815 | struct perf_event_header header; | |
7816 | ||
7817 | u32 pid; | |
7818 | u32 tid; | |
7819 | u64 nr_namespaces; | |
7820 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7821 | } event_id; | |
7822 | }; | |
7823 | ||
7824 | static int perf_event_namespaces_match(struct perf_event *event) | |
7825 | { | |
7826 | return event->attr.namespaces; | |
7827 | } | |
7828 | ||
7829 | static void perf_event_namespaces_output(struct perf_event *event, | |
7830 | void *data) | |
7831 | { | |
7832 | struct perf_namespaces_event *namespaces_event = data; | |
7833 | struct perf_output_handle handle; | |
7834 | struct perf_sample_data sample; | |
34900ec5 | 7835 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7836 | int ret; |
7837 | ||
7838 | if (!perf_event_namespaces_match(event)) | |
7839 | return; | |
7840 | ||
7841 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7842 | &sample, event); | |
267fb273 | 7843 | ret = perf_output_begin(&handle, &sample, event, |
e4222673 HB |
7844 | namespaces_event->event_id.header.size); |
7845 | if (ret) | |
34900ec5 | 7846 | goto out; |
e4222673 HB |
7847 | |
7848 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7849 | namespaces_event->task); | |
7850 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7851 | namespaces_event->task); | |
7852 | ||
7853 | perf_output_put(&handle, namespaces_event->event_id); | |
7854 | ||
7855 | perf_event__output_id_sample(event, &handle, &sample); | |
7856 | ||
7857 | perf_output_end(&handle); | |
34900ec5 JO |
7858 | out: |
7859 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7860 | } |
7861 | ||
7862 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7863 | struct task_struct *task, | |
7864 | const struct proc_ns_operations *ns_ops) | |
7865 | { | |
7866 | struct path ns_path; | |
7867 | struct inode *ns_inode; | |
ce623f89 | 7868 | int error; |
e4222673 HB |
7869 | |
7870 | error = ns_get_path(&ns_path, task, ns_ops); | |
7871 | if (!error) { | |
7872 | ns_inode = ns_path.dentry->d_inode; | |
7873 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7874 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7875 | path_put(&ns_path); |
e4222673 HB |
7876 | } |
7877 | } | |
7878 | ||
7879 | void perf_event_namespaces(struct task_struct *task) | |
7880 | { | |
7881 | struct perf_namespaces_event namespaces_event; | |
7882 | struct perf_ns_link_info *ns_link_info; | |
7883 | ||
7884 | if (!atomic_read(&nr_namespaces_events)) | |
7885 | return; | |
7886 | ||
7887 | namespaces_event = (struct perf_namespaces_event){ | |
7888 | .task = task, | |
7889 | .event_id = { | |
7890 | .header = { | |
7891 | .type = PERF_RECORD_NAMESPACES, | |
7892 | .misc = 0, | |
7893 | .size = sizeof(namespaces_event.event_id), | |
7894 | }, | |
7895 | /* .pid */ | |
7896 | /* .tid */ | |
7897 | .nr_namespaces = NR_NAMESPACES, | |
7898 | /* .link_info[NR_NAMESPACES] */ | |
7899 | }, | |
7900 | }; | |
7901 | ||
7902 | ns_link_info = namespaces_event.event_id.link_info; | |
7903 | ||
7904 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7905 | task, &mntns_operations); | |
7906 | ||
7907 | #ifdef CONFIG_USER_NS | |
7908 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7909 | task, &userns_operations); | |
7910 | #endif | |
7911 | #ifdef CONFIG_NET_NS | |
7912 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7913 | task, &netns_operations); | |
7914 | #endif | |
7915 | #ifdef CONFIG_UTS_NS | |
7916 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7917 | task, &utsns_operations); | |
7918 | #endif | |
7919 | #ifdef CONFIG_IPC_NS | |
7920 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7921 | task, &ipcns_operations); | |
7922 | #endif | |
7923 | #ifdef CONFIG_PID_NS | |
7924 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7925 | task, &pidns_operations); | |
7926 | #endif | |
7927 | #ifdef CONFIG_CGROUPS | |
7928 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7929 | task, &cgroupns_operations); | |
7930 | #endif | |
7931 | ||
7932 | perf_iterate_sb(perf_event_namespaces_output, | |
7933 | &namespaces_event, | |
7934 | NULL); | |
7935 | } | |
7936 | ||
96aaab68 NK |
7937 | /* |
7938 | * cgroup tracking | |
7939 | */ | |
7940 | #ifdef CONFIG_CGROUP_PERF | |
7941 | ||
7942 | struct perf_cgroup_event { | |
7943 | char *path; | |
7944 | int path_size; | |
7945 | struct { | |
7946 | struct perf_event_header header; | |
7947 | u64 id; | |
7948 | char path[]; | |
7949 | } event_id; | |
7950 | }; | |
7951 | ||
7952 | static int perf_event_cgroup_match(struct perf_event *event) | |
7953 | { | |
7954 | return event->attr.cgroup; | |
7955 | } | |
7956 | ||
7957 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
7958 | { | |
7959 | struct perf_cgroup_event *cgroup_event = data; | |
7960 | struct perf_output_handle handle; | |
7961 | struct perf_sample_data sample; | |
7962 | u16 header_size = cgroup_event->event_id.header.size; | |
7963 | int ret; | |
7964 | ||
7965 | if (!perf_event_cgroup_match(event)) | |
7966 | return; | |
7967 | ||
7968 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
7969 | &sample, event); | |
267fb273 | 7970 | ret = perf_output_begin(&handle, &sample, event, |
96aaab68 NK |
7971 | cgroup_event->event_id.header.size); |
7972 | if (ret) | |
7973 | goto out; | |
7974 | ||
7975 | perf_output_put(&handle, cgroup_event->event_id); | |
7976 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
7977 | ||
7978 | perf_event__output_id_sample(event, &handle, &sample); | |
7979 | ||
7980 | perf_output_end(&handle); | |
7981 | out: | |
7982 | cgroup_event->event_id.header.size = header_size; | |
7983 | } | |
7984 | ||
7985 | static void perf_event_cgroup(struct cgroup *cgrp) | |
7986 | { | |
7987 | struct perf_cgroup_event cgroup_event; | |
7988 | char path_enomem[16] = "//enomem"; | |
7989 | char *pathname; | |
7990 | size_t size; | |
7991 | ||
7992 | if (!atomic_read(&nr_cgroup_events)) | |
7993 | return; | |
7994 | ||
7995 | cgroup_event = (struct perf_cgroup_event){ | |
7996 | .event_id = { | |
7997 | .header = { | |
7998 | .type = PERF_RECORD_CGROUP, | |
7999 | .misc = 0, | |
8000 | .size = sizeof(cgroup_event.event_id), | |
8001 | }, | |
8002 | .id = cgroup_id(cgrp), | |
8003 | }, | |
8004 | }; | |
8005 | ||
8006 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
8007 | if (pathname == NULL) { | |
8008 | cgroup_event.path = path_enomem; | |
8009 | } else { | |
8010 | /* just to be sure to have enough space for alignment */ | |
8011 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
8012 | cgroup_event.path = pathname; | |
8013 | } | |
8014 | ||
8015 | /* | |
8016 | * Since our buffer works in 8 byte units we need to align our string | |
8017 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8018 | * zero'd out to avoid leaking random bits to userspace. | |
8019 | */ | |
8020 | size = strlen(cgroup_event.path) + 1; | |
8021 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8022 | cgroup_event.path[size++] = '\0'; | |
8023 | ||
8024 | cgroup_event.event_id.header.size += size; | |
8025 | cgroup_event.path_size = size; | |
8026 | ||
8027 | perf_iterate_sb(perf_event_cgroup_output, | |
8028 | &cgroup_event, | |
8029 | NULL); | |
8030 | ||
8031 | kfree(pathname); | |
8032 | } | |
8033 | ||
8034 | #endif | |
8035 | ||
0a4a9391 PZ |
8036 | /* |
8037 | * mmap tracking | |
8038 | */ | |
8039 | ||
8040 | struct perf_mmap_event { | |
089dd79d PZ |
8041 | struct vm_area_struct *vma; |
8042 | ||
8043 | const char *file_name; | |
8044 | int file_size; | |
13d7a241 SE |
8045 | int maj, min; |
8046 | u64 ino; | |
8047 | u64 ino_generation; | |
f972eb63 | 8048 | u32 prot, flags; |
0a4a9391 PZ |
8049 | |
8050 | struct { | |
8051 | struct perf_event_header header; | |
8052 | ||
8053 | u32 pid; | |
8054 | u32 tid; | |
8055 | u64 start; | |
8056 | u64 len; | |
8057 | u64 pgoff; | |
cdd6c482 | 8058 | } event_id; |
0a4a9391 PZ |
8059 | }; |
8060 | ||
67516844 JO |
8061 | static int perf_event_mmap_match(struct perf_event *event, |
8062 | void *data) | |
8063 | { | |
8064 | struct perf_mmap_event *mmap_event = data; | |
8065 | struct vm_area_struct *vma = mmap_event->vma; | |
8066 | int executable = vma->vm_flags & VM_EXEC; | |
8067 | ||
8068 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 8069 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
8070 | } |
8071 | ||
cdd6c482 | 8072 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 8073 | void *data) |
0a4a9391 | 8074 | { |
52d857a8 | 8075 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 8076 | struct perf_output_handle handle; |
c980d109 | 8077 | struct perf_sample_data sample; |
cdd6c482 | 8078 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 8079 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 8080 | int ret; |
0a4a9391 | 8081 | |
67516844 JO |
8082 | if (!perf_event_mmap_match(event, data)) |
8083 | return; | |
8084 | ||
13d7a241 SE |
8085 | if (event->attr.mmap2) { |
8086 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
8087 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
8088 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
8089 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 8090 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
8091 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
8092 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
8093 | } |
8094 | ||
c980d109 | 8095 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
267fb273 | 8096 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8097 | mmap_event->event_id.header.size); |
0a4a9391 | 8098 | if (ret) |
c980d109 | 8099 | goto out; |
0a4a9391 | 8100 | |
cdd6c482 IM |
8101 | mmap_event->event_id.pid = perf_event_pid(event, current); |
8102 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 8103 | |
cdd6c482 | 8104 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
8105 | |
8106 | if (event->attr.mmap2) { | |
8107 | perf_output_put(&handle, mmap_event->maj); | |
8108 | perf_output_put(&handle, mmap_event->min); | |
8109 | perf_output_put(&handle, mmap_event->ino); | |
8110 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
8111 | perf_output_put(&handle, mmap_event->prot); |
8112 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
8113 | } |
8114 | ||
76369139 | 8115 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 8116 | mmap_event->file_size); |
c980d109 ACM |
8117 | |
8118 | perf_event__output_id_sample(event, &handle, &sample); | |
8119 | ||
78d613eb | 8120 | perf_output_end(&handle); |
c980d109 ACM |
8121 | out: |
8122 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 8123 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
8124 | } |
8125 | ||
cdd6c482 | 8126 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 8127 | { |
089dd79d PZ |
8128 | struct vm_area_struct *vma = mmap_event->vma; |
8129 | struct file *file = vma->vm_file; | |
13d7a241 SE |
8130 | int maj = 0, min = 0; |
8131 | u64 ino = 0, gen = 0; | |
f972eb63 | 8132 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
8133 | unsigned int size; |
8134 | char tmp[16]; | |
8135 | char *buf = NULL; | |
2c42cfbf | 8136 | char *name; |
413ee3b4 | 8137 | |
0b3589be PZ |
8138 | if (vma->vm_flags & VM_READ) |
8139 | prot |= PROT_READ; | |
8140 | if (vma->vm_flags & VM_WRITE) | |
8141 | prot |= PROT_WRITE; | |
8142 | if (vma->vm_flags & VM_EXEC) | |
8143 | prot |= PROT_EXEC; | |
8144 | ||
8145 | if (vma->vm_flags & VM_MAYSHARE) | |
8146 | flags = MAP_SHARED; | |
8147 | else | |
8148 | flags = MAP_PRIVATE; | |
8149 | ||
8150 | if (vma->vm_flags & VM_DENYWRITE) | |
8151 | flags |= MAP_DENYWRITE; | |
8152 | if (vma->vm_flags & VM_MAYEXEC) | |
8153 | flags |= MAP_EXECUTABLE; | |
8154 | if (vma->vm_flags & VM_LOCKED) | |
8155 | flags |= MAP_LOCKED; | |
03911132 | 8156 | if (is_vm_hugetlb_page(vma)) |
0b3589be PZ |
8157 | flags |= MAP_HUGETLB; |
8158 | ||
0a4a9391 | 8159 | if (file) { |
13d7a241 SE |
8160 | struct inode *inode; |
8161 | dev_t dev; | |
3ea2f2b9 | 8162 | |
2c42cfbf | 8163 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 8164 | if (!buf) { |
c7e548b4 ON |
8165 | name = "//enomem"; |
8166 | goto cpy_name; | |
0a4a9391 | 8167 | } |
413ee3b4 | 8168 | /* |
3ea2f2b9 | 8169 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
8170 | * need to add enough zero bytes after the string to handle |
8171 | * the 64bit alignment we do later. | |
8172 | */ | |
9bf39ab2 | 8173 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 8174 | if (IS_ERR(name)) { |
c7e548b4 ON |
8175 | name = "//toolong"; |
8176 | goto cpy_name; | |
0a4a9391 | 8177 | } |
13d7a241 SE |
8178 | inode = file_inode(vma->vm_file); |
8179 | dev = inode->i_sb->s_dev; | |
8180 | ino = inode->i_ino; | |
8181 | gen = inode->i_generation; | |
8182 | maj = MAJOR(dev); | |
8183 | min = MINOR(dev); | |
f972eb63 | 8184 | |
c7e548b4 | 8185 | goto got_name; |
0a4a9391 | 8186 | } else { |
fbe26abe JO |
8187 | if (vma->vm_ops && vma->vm_ops->name) { |
8188 | name = (char *) vma->vm_ops->name(vma); | |
8189 | if (name) | |
8190 | goto cpy_name; | |
8191 | } | |
8192 | ||
2c42cfbf | 8193 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8194 | if (name) |
8195 | goto cpy_name; | |
089dd79d | 8196 | |
32c5fb7e | 8197 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8198 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8199 | name = "[heap]"; |
8200 | goto cpy_name; | |
32c5fb7e ON |
8201 | } |
8202 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8203 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8204 | name = "[stack]"; |
8205 | goto cpy_name; | |
089dd79d PZ |
8206 | } |
8207 | ||
c7e548b4 ON |
8208 | name = "//anon"; |
8209 | goto cpy_name; | |
0a4a9391 PZ |
8210 | } |
8211 | ||
c7e548b4 ON |
8212 | cpy_name: |
8213 | strlcpy(tmp, name, sizeof(tmp)); | |
8214 | name = tmp; | |
0a4a9391 | 8215 | got_name: |
2c42cfbf PZ |
8216 | /* |
8217 | * Since our buffer works in 8 byte units we need to align our string | |
8218 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8219 | * zero'd out to avoid leaking random bits to userspace. | |
8220 | */ | |
8221 | size = strlen(name)+1; | |
8222 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8223 | name[size++] = '\0'; | |
0a4a9391 PZ |
8224 | |
8225 | mmap_event->file_name = name; | |
8226 | mmap_event->file_size = size; | |
13d7a241 SE |
8227 | mmap_event->maj = maj; |
8228 | mmap_event->min = min; | |
8229 | mmap_event->ino = ino; | |
8230 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8231 | mmap_event->prot = prot; |
8232 | mmap_event->flags = flags; | |
0a4a9391 | 8233 | |
2fe85427 SE |
8234 | if (!(vma->vm_flags & VM_EXEC)) |
8235 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8236 | ||
cdd6c482 | 8237 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8238 | |
aab5b71e | 8239 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8240 | mmap_event, |
8241 | NULL); | |
665c2142 | 8242 | |
0a4a9391 PZ |
8243 | kfree(buf); |
8244 | } | |
8245 | ||
375637bc AS |
8246 | /* |
8247 | * Check whether inode and address range match filter criteria. | |
8248 | */ | |
8249 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8250 | struct file *file, unsigned long offset, | |
8251 | unsigned long size) | |
8252 | { | |
7f635ff1 MP |
8253 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8254 | if (!filter->path.dentry) | |
8255 | return false; | |
8256 | ||
9511bce9 | 8257 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8258 | return false; |
8259 | ||
8260 | if (filter->offset > offset + size) | |
8261 | return false; | |
8262 | ||
8263 | if (filter->offset + filter->size < offset) | |
8264 | return false; | |
8265 | ||
8266 | return true; | |
8267 | } | |
8268 | ||
c60f83b8 AS |
8269 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8270 | struct vm_area_struct *vma, | |
8271 | struct perf_addr_filter_range *fr) | |
8272 | { | |
8273 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8274 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8275 | struct file *file = vma->vm_file; | |
8276 | ||
8277 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8278 | return false; | |
8279 | ||
8280 | if (filter->offset < off) { | |
8281 | fr->start = vma->vm_start; | |
8282 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8283 | } else { | |
8284 | fr->start = vma->vm_start + filter->offset - off; | |
8285 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8286 | } | |
8287 | ||
8288 | return true; | |
8289 | } | |
8290 | ||
375637bc AS |
8291 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8292 | { | |
8293 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8294 | struct vm_area_struct *vma = data; | |
375637bc AS |
8295 | struct perf_addr_filter *filter; |
8296 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8297 | unsigned long flags; |
375637bc AS |
8298 | |
8299 | if (!has_addr_filter(event)) | |
8300 | return; | |
8301 | ||
c60f83b8 | 8302 | if (!vma->vm_file) |
375637bc AS |
8303 | return; |
8304 | ||
8305 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8306 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8307 | if (perf_addr_filter_vma_adjust(filter, vma, |
8308 | &event->addr_filter_ranges[count])) | |
375637bc | 8309 | restart++; |
375637bc AS |
8310 | |
8311 | count++; | |
8312 | } | |
8313 | ||
8314 | if (restart) | |
8315 | event->addr_filters_gen++; | |
8316 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8317 | ||
8318 | if (restart) | |
767ae086 | 8319 | perf_event_stop(event, 1); |
375637bc AS |
8320 | } |
8321 | ||
8322 | /* | |
8323 | * Adjust all task's events' filters to the new vma | |
8324 | */ | |
8325 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8326 | { | |
8327 | struct perf_event_context *ctx; | |
8328 | int ctxn; | |
8329 | ||
12b40a23 MP |
8330 | /* |
8331 | * Data tracing isn't supported yet and as such there is no need | |
8332 | * to keep track of anything that isn't related to executable code: | |
8333 | */ | |
8334 | if (!(vma->vm_flags & VM_EXEC)) | |
8335 | return; | |
8336 | ||
375637bc AS |
8337 | rcu_read_lock(); |
8338 | for_each_task_context_nr(ctxn) { | |
8339 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8340 | if (!ctx) | |
8341 | continue; | |
8342 | ||
aab5b71e | 8343 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8344 | } |
8345 | rcu_read_unlock(); | |
8346 | } | |
8347 | ||
3af9e859 | 8348 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8349 | { |
9ee318a7 PZ |
8350 | struct perf_mmap_event mmap_event; |
8351 | ||
cdd6c482 | 8352 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8353 | return; |
8354 | ||
8355 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8356 | .vma = vma, |
573402db PZ |
8357 | /* .file_name */ |
8358 | /* .file_size */ | |
cdd6c482 | 8359 | .event_id = { |
573402db | 8360 | .header = { |
cdd6c482 | 8361 | .type = PERF_RECORD_MMAP, |
39447b38 | 8362 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8363 | /* .size */ |
8364 | }, | |
8365 | /* .pid */ | |
8366 | /* .tid */ | |
089dd79d PZ |
8367 | .start = vma->vm_start, |
8368 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8369 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8370 | }, |
13d7a241 SE |
8371 | /* .maj (attr_mmap2 only) */ |
8372 | /* .min (attr_mmap2 only) */ | |
8373 | /* .ino (attr_mmap2 only) */ | |
8374 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8375 | /* .prot (attr_mmap2 only) */ |
8376 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8377 | }; |
8378 | ||
375637bc | 8379 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8380 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8381 | } |
8382 | ||
68db7e98 AS |
8383 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8384 | unsigned long size, u64 flags) | |
8385 | { | |
8386 | struct perf_output_handle handle; | |
8387 | struct perf_sample_data sample; | |
8388 | struct perf_aux_event { | |
8389 | struct perf_event_header header; | |
8390 | u64 offset; | |
8391 | u64 size; | |
8392 | u64 flags; | |
8393 | } rec = { | |
8394 | .header = { | |
8395 | .type = PERF_RECORD_AUX, | |
8396 | .misc = 0, | |
8397 | .size = sizeof(rec), | |
8398 | }, | |
8399 | .offset = head, | |
8400 | .size = size, | |
8401 | .flags = flags, | |
8402 | }; | |
8403 | int ret; | |
8404 | ||
8405 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8406 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
68db7e98 AS |
8407 | |
8408 | if (ret) | |
8409 | return; | |
8410 | ||
8411 | perf_output_put(&handle, rec); | |
8412 | perf_event__output_id_sample(event, &handle, &sample); | |
8413 | ||
8414 | perf_output_end(&handle); | |
8415 | } | |
8416 | ||
f38b0dbb KL |
8417 | /* |
8418 | * Lost/dropped samples logging | |
8419 | */ | |
8420 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8421 | { | |
8422 | struct perf_output_handle handle; | |
8423 | struct perf_sample_data sample; | |
8424 | int ret; | |
8425 | ||
8426 | struct { | |
8427 | struct perf_event_header header; | |
8428 | u64 lost; | |
8429 | } lost_samples_event = { | |
8430 | .header = { | |
8431 | .type = PERF_RECORD_LOST_SAMPLES, | |
8432 | .misc = 0, | |
8433 | .size = sizeof(lost_samples_event), | |
8434 | }, | |
8435 | .lost = lost, | |
8436 | }; | |
8437 | ||
8438 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8439 | ||
267fb273 | 8440 | ret = perf_output_begin(&handle, &sample, event, |
f38b0dbb KL |
8441 | lost_samples_event.header.size); |
8442 | if (ret) | |
8443 | return; | |
8444 | ||
8445 | perf_output_put(&handle, lost_samples_event); | |
8446 | perf_event__output_id_sample(event, &handle, &sample); | |
8447 | perf_output_end(&handle); | |
8448 | } | |
8449 | ||
45ac1403 AH |
8450 | /* |
8451 | * context_switch tracking | |
8452 | */ | |
8453 | ||
8454 | struct perf_switch_event { | |
8455 | struct task_struct *task; | |
8456 | struct task_struct *next_prev; | |
8457 | ||
8458 | struct { | |
8459 | struct perf_event_header header; | |
8460 | u32 next_prev_pid; | |
8461 | u32 next_prev_tid; | |
8462 | } event_id; | |
8463 | }; | |
8464 | ||
8465 | static int perf_event_switch_match(struct perf_event *event) | |
8466 | { | |
8467 | return event->attr.context_switch; | |
8468 | } | |
8469 | ||
8470 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8471 | { | |
8472 | struct perf_switch_event *se = data; | |
8473 | struct perf_output_handle handle; | |
8474 | struct perf_sample_data sample; | |
8475 | int ret; | |
8476 | ||
8477 | if (!perf_event_switch_match(event)) | |
8478 | return; | |
8479 | ||
8480 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8481 | if (event->ctx->task) { | |
8482 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8483 | se->event_id.header.size = sizeof(se->event_id.header); | |
8484 | } else { | |
8485 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8486 | se->event_id.header.size = sizeof(se->event_id); | |
8487 | se->event_id.next_prev_pid = | |
8488 | perf_event_pid(event, se->next_prev); | |
8489 | se->event_id.next_prev_tid = | |
8490 | perf_event_tid(event, se->next_prev); | |
8491 | } | |
8492 | ||
8493 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8494 | ||
267fb273 | 8495 | ret = perf_output_begin(&handle, &sample, event, se->event_id.header.size); |
45ac1403 AH |
8496 | if (ret) |
8497 | return; | |
8498 | ||
8499 | if (event->ctx->task) | |
8500 | perf_output_put(&handle, se->event_id.header); | |
8501 | else | |
8502 | perf_output_put(&handle, se->event_id); | |
8503 | ||
8504 | perf_event__output_id_sample(event, &handle, &sample); | |
8505 | ||
8506 | perf_output_end(&handle); | |
8507 | } | |
8508 | ||
8509 | static void perf_event_switch(struct task_struct *task, | |
8510 | struct task_struct *next_prev, bool sched_in) | |
8511 | { | |
8512 | struct perf_switch_event switch_event; | |
8513 | ||
8514 | /* N.B. caller checks nr_switch_events != 0 */ | |
8515 | ||
8516 | switch_event = (struct perf_switch_event){ | |
8517 | .task = task, | |
8518 | .next_prev = next_prev, | |
8519 | .event_id = { | |
8520 | .header = { | |
8521 | /* .type */ | |
8522 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8523 | /* .size */ | |
8524 | }, | |
8525 | /* .next_prev_pid */ | |
8526 | /* .next_prev_tid */ | |
8527 | }, | |
8528 | }; | |
8529 | ||
101592b4 AB |
8530 | if (!sched_in && task->state == TASK_RUNNING) |
8531 | switch_event.event_id.header.misc |= | |
8532 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8533 | ||
aab5b71e | 8534 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8535 | &switch_event, |
8536 | NULL); | |
8537 | } | |
8538 | ||
a78ac325 PZ |
8539 | /* |
8540 | * IRQ throttle logging | |
8541 | */ | |
8542 | ||
cdd6c482 | 8543 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8544 | { |
8545 | struct perf_output_handle handle; | |
c980d109 | 8546 | struct perf_sample_data sample; |
a78ac325 PZ |
8547 | int ret; |
8548 | ||
8549 | struct { | |
8550 | struct perf_event_header header; | |
8551 | u64 time; | |
cca3f454 | 8552 | u64 id; |
7f453c24 | 8553 | u64 stream_id; |
a78ac325 PZ |
8554 | } throttle_event = { |
8555 | .header = { | |
cdd6c482 | 8556 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8557 | .misc = 0, |
8558 | .size = sizeof(throttle_event), | |
8559 | }, | |
34f43927 | 8560 | .time = perf_event_clock(event), |
cdd6c482 IM |
8561 | .id = primary_event_id(event), |
8562 | .stream_id = event->id, | |
a78ac325 PZ |
8563 | }; |
8564 | ||
966ee4d6 | 8565 | if (enable) |
cdd6c482 | 8566 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8567 | |
c980d109 ACM |
8568 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8569 | ||
267fb273 | 8570 | ret = perf_output_begin(&handle, &sample, event, |
a7ac67ea | 8571 | throttle_event.header.size); |
a78ac325 PZ |
8572 | if (ret) |
8573 | return; | |
8574 | ||
8575 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8576 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8577 | perf_output_end(&handle); |
8578 | } | |
8579 | ||
76193a94 SL |
8580 | /* |
8581 | * ksymbol register/unregister tracking | |
8582 | */ | |
8583 | ||
8584 | struct perf_ksymbol_event { | |
8585 | const char *name; | |
8586 | int name_len; | |
8587 | struct { | |
8588 | struct perf_event_header header; | |
8589 | u64 addr; | |
8590 | u32 len; | |
8591 | u16 ksym_type; | |
8592 | u16 flags; | |
8593 | } event_id; | |
8594 | }; | |
8595 | ||
8596 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8597 | { | |
8598 | return event->attr.ksymbol; | |
8599 | } | |
8600 | ||
8601 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8602 | { | |
8603 | struct perf_ksymbol_event *ksymbol_event = data; | |
8604 | struct perf_output_handle handle; | |
8605 | struct perf_sample_data sample; | |
8606 | int ret; | |
8607 | ||
8608 | if (!perf_event_ksymbol_match(event)) | |
8609 | return; | |
8610 | ||
8611 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8612 | &sample, event); | |
267fb273 | 8613 | ret = perf_output_begin(&handle, &sample, event, |
76193a94 SL |
8614 | ksymbol_event->event_id.header.size); |
8615 | if (ret) | |
8616 | return; | |
8617 | ||
8618 | perf_output_put(&handle, ksymbol_event->event_id); | |
8619 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8620 | perf_event__output_id_sample(event, &handle, &sample); | |
8621 | ||
8622 | perf_output_end(&handle); | |
8623 | } | |
8624 | ||
8625 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8626 | const char *sym) | |
8627 | { | |
8628 | struct perf_ksymbol_event ksymbol_event; | |
8629 | char name[KSYM_NAME_LEN]; | |
8630 | u16 flags = 0; | |
8631 | int name_len; | |
8632 | ||
8633 | if (!atomic_read(&nr_ksymbol_events)) | |
8634 | return; | |
8635 | ||
8636 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8637 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8638 | goto err; | |
8639 | ||
8640 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8641 | name_len = strlen(name) + 1; | |
8642 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8643 | name[name_len++] = '\0'; | |
8644 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8645 | ||
8646 | if (unregister) | |
8647 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8648 | ||
8649 | ksymbol_event = (struct perf_ksymbol_event){ | |
8650 | .name = name, | |
8651 | .name_len = name_len, | |
8652 | .event_id = { | |
8653 | .header = { | |
8654 | .type = PERF_RECORD_KSYMBOL, | |
8655 | .size = sizeof(ksymbol_event.event_id) + | |
8656 | name_len, | |
8657 | }, | |
8658 | .addr = addr, | |
8659 | .len = len, | |
8660 | .ksym_type = ksym_type, | |
8661 | .flags = flags, | |
8662 | }, | |
8663 | }; | |
8664 | ||
8665 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8666 | return; | |
8667 | err: | |
8668 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8669 | } | |
8670 | ||
6ee52e2a SL |
8671 | /* |
8672 | * bpf program load/unload tracking | |
8673 | */ | |
8674 | ||
8675 | struct perf_bpf_event { | |
8676 | struct bpf_prog *prog; | |
8677 | struct { | |
8678 | struct perf_event_header header; | |
8679 | u16 type; | |
8680 | u16 flags; | |
8681 | u32 id; | |
8682 | u8 tag[BPF_TAG_SIZE]; | |
8683 | } event_id; | |
8684 | }; | |
8685 | ||
8686 | static int perf_event_bpf_match(struct perf_event *event) | |
8687 | { | |
8688 | return event->attr.bpf_event; | |
8689 | } | |
8690 | ||
8691 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8692 | { | |
8693 | struct perf_bpf_event *bpf_event = data; | |
8694 | struct perf_output_handle handle; | |
8695 | struct perf_sample_data sample; | |
8696 | int ret; | |
8697 | ||
8698 | if (!perf_event_bpf_match(event)) | |
8699 | return; | |
8700 | ||
8701 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8702 | &sample, event); | |
267fb273 | 8703 | ret = perf_output_begin(&handle, data, event, |
6ee52e2a SL |
8704 | bpf_event->event_id.header.size); |
8705 | if (ret) | |
8706 | return; | |
8707 | ||
8708 | perf_output_put(&handle, bpf_event->event_id); | |
8709 | perf_event__output_id_sample(event, &handle, &sample); | |
8710 | ||
8711 | perf_output_end(&handle); | |
8712 | } | |
8713 | ||
8714 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8715 | enum perf_bpf_event_type type) | |
8716 | { | |
8717 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8718 | int i; |
8719 | ||
8720 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8721 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8722 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8723 | prog->jited_len, unregister, |
8724 | prog->aux->ksym.name); | |
6ee52e2a SL |
8725 | } else { |
8726 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8727 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8728 | ||
6ee52e2a SL |
8729 | perf_event_ksymbol( |
8730 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8731 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8732 | subprog->jited_len, unregister, |
8733 | prog->aux->ksym.name); | |
6ee52e2a SL |
8734 | } |
8735 | } | |
8736 | } | |
8737 | ||
8738 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8739 | enum perf_bpf_event_type type, | |
8740 | u16 flags) | |
8741 | { | |
8742 | struct perf_bpf_event bpf_event; | |
8743 | ||
8744 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8745 | type >= PERF_BPF_EVENT_MAX) | |
8746 | return; | |
8747 | ||
8748 | switch (type) { | |
8749 | case PERF_BPF_EVENT_PROG_LOAD: | |
8750 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8751 | if (atomic_read(&nr_ksymbol_events)) | |
8752 | perf_event_bpf_emit_ksymbols(prog, type); | |
8753 | break; | |
8754 | default: | |
8755 | break; | |
8756 | } | |
8757 | ||
8758 | if (!atomic_read(&nr_bpf_events)) | |
8759 | return; | |
8760 | ||
8761 | bpf_event = (struct perf_bpf_event){ | |
8762 | .prog = prog, | |
8763 | .event_id = { | |
8764 | .header = { | |
8765 | .type = PERF_RECORD_BPF_EVENT, | |
8766 | .size = sizeof(bpf_event.event_id), | |
8767 | }, | |
8768 | .type = type, | |
8769 | .flags = flags, | |
8770 | .id = prog->aux->id, | |
8771 | }, | |
8772 | }; | |
8773 | ||
8774 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8775 | ||
8776 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8777 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8778 | } | |
8779 | ||
e17d43b9 AH |
8780 | struct perf_text_poke_event { |
8781 | const void *old_bytes; | |
8782 | const void *new_bytes; | |
8783 | size_t pad; | |
8784 | u16 old_len; | |
8785 | u16 new_len; | |
8786 | ||
8787 | struct { | |
8788 | struct perf_event_header header; | |
8789 | ||
8790 | u64 addr; | |
8791 | } event_id; | |
8792 | }; | |
8793 | ||
8794 | static int perf_event_text_poke_match(struct perf_event *event) | |
8795 | { | |
8796 | return event->attr.text_poke; | |
8797 | } | |
8798 | ||
8799 | static void perf_event_text_poke_output(struct perf_event *event, void *data) | |
8800 | { | |
8801 | struct perf_text_poke_event *text_poke_event = data; | |
8802 | struct perf_output_handle handle; | |
8803 | struct perf_sample_data sample; | |
8804 | u64 padding = 0; | |
8805 | int ret; | |
8806 | ||
8807 | if (!perf_event_text_poke_match(event)) | |
8808 | return; | |
8809 | ||
8810 | perf_event_header__init_id(&text_poke_event->event_id.header, &sample, event); | |
8811 | ||
267fb273 PZ |
8812 | ret = perf_output_begin(&handle, &sample, event, |
8813 | text_poke_event->event_id.header.size); | |
e17d43b9 AH |
8814 | if (ret) |
8815 | return; | |
8816 | ||
8817 | perf_output_put(&handle, text_poke_event->event_id); | |
8818 | perf_output_put(&handle, text_poke_event->old_len); | |
8819 | perf_output_put(&handle, text_poke_event->new_len); | |
8820 | ||
8821 | __output_copy(&handle, text_poke_event->old_bytes, text_poke_event->old_len); | |
8822 | __output_copy(&handle, text_poke_event->new_bytes, text_poke_event->new_len); | |
8823 | ||
8824 | if (text_poke_event->pad) | |
8825 | __output_copy(&handle, &padding, text_poke_event->pad); | |
8826 | ||
8827 | perf_event__output_id_sample(event, &handle, &sample); | |
8828 | ||
8829 | perf_output_end(&handle); | |
8830 | } | |
8831 | ||
8832 | void perf_event_text_poke(const void *addr, const void *old_bytes, | |
8833 | size_t old_len, const void *new_bytes, size_t new_len) | |
8834 | { | |
8835 | struct perf_text_poke_event text_poke_event; | |
8836 | size_t tot, pad; | |
8837 | ||
8838 | if (!atomic_read(&nr_text_poke_events)) | |
8839 | return; | |
8840 | ||
8841 | tot = sizeof(text_poke_event.old_len) + old_len; | |
8842 | tot += sizeof(text_poke_event.new_len) + new_len; | |
8843 | pad = ALIGN(tot, sizeof(u64)) - tot; | |
8844 | ||
8845 | text_poke_event = (struct perf_text_poke_event){ | |
8846 | .old_bytes = old_bytes, | |
8847 | .new_bytes = new_bytes, | |
8848 | .pad = pad, | |
8849 | .old_len = old_len, | |
8850 | .new_len = new_len, | |
8851 | .event_id = { | |
8852 | .header = { | |
8853 | .type = PERF_RECORD_TEXT_POKE, | |
8854 | .misc = PERF_RECORD_MISC_KERNEL, | |
8855 | .size = sizeof(text_poke_event.event_id) + tot + pad, | |
8856 | }, | |
8857 | .addr = (unsigned long)addr, | |
8858 | }, | |
8859 | }; | |
8860 | ||
8861 | perf_iterate_sb(perf_event_text_poke_output, &text_poke_event, NULL); | |
8862 | } | |
8863 | ||
8d4e6c4c AS |
8864 | void perf_event_itrace_started(struct perf_event *event) |
8865 | { | |
8866 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8867 | } | |
8868 | ||
ec0d7729 AS |
8869 | static void perf_log_itrace_start(struct perf_event *event) |
8870 | { | |
8871 | struct perf_output_handle handle; | |
8872 | struct perf_sample_data sample; | |
8873 | struct perf_aux_event { | |
8874 | struct perf_event_header header; | |
8875 | u32 pid; | |
8876 | u32 tid; | |
8877 | } rec; | |
8878 | int ret; | |
8879 | ||
8880 | if (event->parent) | |
8881 | event = event->parent; | |
8882 | ||
8883 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8884 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8885 | return; |
8886 | ||
ec0d7729 AS |
8887 | rec.header.type = PERF_RECORD_ITRACE_START; |
8888 | rec.header.misc = 0; | |
8889 | rec.header.size = sizeof(rec); | |
8890 | rec.pid = perf_event_pid(event, current); | |
8891 | rec.tid = perf_event_tid(event, current); | |
8892 | ||
8893 | perf_event_header__init_id(&rec.header, &sample, event); | |
267fb273 | 8894 | ret = perf_output_begin(&handle, &sample, event, rec.header.size); |
ec0d7729 AS |
8895 | |
8896 | if (ret) | |
8897 | return; | |
8898 | ||
8899 | perf_output_put(&handle, rec); | |
8900 | perf_event__output_id_sample(event, &handle, &sample); | |
8901 | ||
8902 | perf_output_end(&handle); | |
8903 | } | |
8904 | ||
475113d9 JO |
8905 | static int |
8906 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8907 | { |
cdd6c482 | 8908 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8909 | int ret = 0; |
475113d9 | 8910 | u64 seq; |
96398826 | 8911 | |
e050e3f0 SE |
8912 | seq = __this_cpu_read(perf_throttled_seq); |
8913 | if (seq != hwc->interrupts_seq) { | |
8914 | hwc->interrupts_seq = seq; | |
8915 | hwc->interrupts = 1; | |
8916 | } else { | |
8917 | hwc->interrupts++; | |
8918 | if (unlikely(throttle | |
8919 | && hwc->interrupts >= max_samples_per_tick)) { | |
8920 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8921 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8922 | hwc->interrupts = MAX_INTERRUPTS; |
8923 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8924 | ret = 1; |
8925 | } | |
e050e3f0 | 8926 | } |
60db5e09 | 8927 | |
cdd6c482 | 8928 | if (event->attr.freq) { |
def0a9b2 | 8929 | u64 now = perf_clock(); |
abd50713 | 8930 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8931 | |
abd50713 | 8932 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8933 | |
abd50713 | 8934 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8935 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8936 | } |
8937 | ||
475113d9 JO |
8938 | return ret; |
8939 | } | |
8940 | ||
8941 | int perf_event_account_interrupt(struct perf_event *event) | |
8942 | { | |
8943 | return __perf_event_account_interrupt(event, 1); | |
8944 | } | |
8945 | ||
8946 | /* | |
8947 | * Generic event overflow handling, sampling. | |
8948 | */ | |
8949 | ||
8950 | static int __perf_event_overflow(struct perf_event *event, | |
8951 | int throttle, struct perf_sample_data *data, | |
8952 | struct pt_regs *regs) | |
8953 | { | |
8954 | int events = atomic_read(&event->event_limit); | |
8955 | int ret = 0; | |
8956 | ||
8957 | /* | |
8958 | * Non-sampling counters might still use the PMI to fold short | |
8959 | * hardware counters, ignore those. | |
8960 | */ | |
8961 | if (unlikely(!is_sampling_event(event))) | |
8962 | return 0; | |
8963 | ||
8964 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8965 | |
2023b359 PZ |
8966 | /* |
8967 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8968 | * events |
2023b359 PZ |
8969 | */ |
8970 | ||
cdd6c482 IM |
8971 | event->pending_kill = POLL_IN; |
8972 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8973 | ret = 1; |
cdd6c482 | 8974 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8975 | |
8976 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8977 | } |
8978 | ||
aa6a5f3c | 8979 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8980 | |
fed66e2c | 8981 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8982 | event->pending_wakeup = 1; |
8983 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8984 | } |
8985 | ||
79f14641 | 8986 | return ret; |
f6c7d5fe PZ |
8987 | } |
8988 | ||
a8b0ca17 | 8989 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8990 | struct perf_sample_data *data, |
8991 | struct pt_regs *regs) | |
850bc73f | 8992 | { |
a8b0ca17 | 8993 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8994 | } |
8995 | ||
15dbf27c | 8996 | /* |
cdd6c482 | 8997 | * Generic software event infrastructure |
15dbf27c PZ |
8998 | */ |
8999 | ||
b28ab83c PZ |
9000 | struct swevent_htable { |
9001 | struct swevent_hlist *swevent_hlist; | |
9002 | struct mutex hlist_mutex; | |
9003 | int hlist_refcount; | |
9004 | ||
9005 | /* Recursion avoidance in each contexts */ | |
9006 | int recursion[PERF_NR_CONTEXTS]; | |
9007 | }; | |
9008 | ||
9009 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
9010 | ||
7b4b6658 | 9011 | /* |
cdd6c482 IM |
9012 | * We directly increment event->count and keep a second value in |
9013 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
9014 | * is kept in the range [-sample_period, 0] so that we can use the |
9015 | * sign as trigger. | |
9016 | */ | |
9017 | ||
ab573844 | 9018 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 9019 | { |
cdd6c482 | 9020 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
9021 | u64 period = hwc->last_period; |
9022 | u64 nr, offset; | |
9023 | s64 old, val; | |
9024 | ||
9025 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
9026 | |
9027 | again: | |
e7850595 | 9028 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
9029 | if (val < 0) |
9030 | return 0; | |
15dbf27c | 9031 | |
7b4b6658 PZ |
9032 | nr = div64_u64(period + val, period); |
9033 | offset = nr * period; | |
9034 | val -= offset; | |
e7850595 | 9035 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 9036 | goto again; |
15dbf27c | 9037 | |
7b4b6658 | 9038 | return nr; |
15dbf27c PZ |
9039 | } |
9040 | ||
0cff784a | 9041 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 9042 | struct perf_sample_data *data, |
5622f295 | 9043 | struct pt_regs *regs) |
15dbf27c | 9044 | { |
cdd6c482 | 9045 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 9046 | int throttle = 0; |
15dbf27c | 9047 | |
0cff784a PZ |
9048 | if (!overflow) |
9049 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 9050 | |
7b4b6658 PZ |
9051 | if (hwc->interrupts == MAX_INTERRUPTS) |
9052 | return; | |
15dbf27c | 9053 | |
7b4b6658 | 9054 | for (; overflow; overflow--) { |
a8b0ca17 | 9055 | if (__perf_event_overflow(event, throttle, |
5622f295 | 9056 | data, regs)) { |
7b4b6658 PZ |
9057 | /* |
9058 | * We inhibit the overflow from happening when | |
9059 | * hwc->interrupts == MAX_INTERRUPTS. | |
9060 | */ | |
9061 | break; | |
9062 | } | |
cf450a73 | 9063 | throttle = 1; |
7b4b6658 | 9064 | } |
15dbf27c PZ |
9065 | } |
9066 | ||
a4eaf7f1 | 9067 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 9068 | struct perf_sample_data *data, |
5622f295 | 9069 | struct pt_regs *regs) |
7b4b6658 | 9070 | { |
cdd6c482 | 9071 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 9072 | |
e7850595 | 9073 | local64_add(nr, &event->count); |
d6d020e9 | 9074 | |
0cff784a PZ |
9075 | if (!regs) |
9076 | return; | |
9077 | ||
6c7e550f | 9078 | if (!is_sampling_event(event)) |
7b4b6658 | 9079 | return; |
d6d020e9 | 9080 | |
5d81e5cf AV |
9081 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
9082 | data->period = nr; | |
9083 | return perf_swevent_overflow(event, 1, data, regs); | |
9084 | } else | |
9085 | data->period = event->hw.last_period; | |
9086 | ||
0cff784a | 9087 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 9088 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 9089 | |
e7850595 | 9090 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 9091 | return; |
df1a132b | 9092 | |
a8b0ca17 | 9093 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
9094 | } |
9095 | ||
f5ffe02e FW |
9096 | static int perf_exclude_event(struct perf_event *event, |
9097 | struct pt_regs *regs) | |
9098 | { | |
a4eaf7f1 | 9099 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 9100 | return 1; |
a4eaf7f1 | 9101 | |
f5ffe02e FW |
9102 | if (regs) { |
9103 | if (event->attr.exclude_user && user_mode(regs)) | |
9104 | return 1; | |
9105 | ||
9106 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
9107 | return 1; | |
9108 | } | |
9109 | ||
9110 | return 0; | |
9111 | } | |
9112 | ||
cdd6c482 | 9113 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 9114 | enum perf_type_id type, |
6fb2915d LZ |
9115 | u32 event_id, |
9116 | struct perf_sample_data *data, | |
9117 | struct pt_regs *regs) | |
15dbf27c | 9118 | { |
cdd6c482 | 9119 | if (event->attr.type != type) |
a21ca2ca | 9120 | return 0; |
f5ffe02e | 9121 | |
cdd6c482 | 9122 | if (event->attr.config != event_id) |
15dbf27c PZ |
9123 | return 0; |
9124 | ||
f5ffe02e FW |
9125 | if (perf_exclude_event(event, regs)) |
9126 | return 0; | |
15dbf27c PZ |
9127 | |
9128 | return 1; | |
9129 | } | |
9130 | ||
76e1d904 FW |
9131 | static inline u64 swevent_hash(u64 type, u32 event_id) |
9132 | { | |
9133 | u64 val = event_id | (type << 32); | |
9134 | ||
9135 | return hash_64(val, SWEVENT_HLIST_BITS); | |
9136 | } | |
9137 | ||
49f135ed FW |
9138 | static inline struct hlist_head * |
9139 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 9140 | { |
49f135ed FW |
9141 | u64 hash = swevent_hash(type, event_id); |
9142 | ||
9143 | return &hlist->heads[hash]; | |
9144 | } | |
76e1d904 | 9145 | |
49f135ed FW |
9146 | /* For the read side: events when they trigger */ |
9147 | static inline struct hlist_head * | |
b28ab83c | 9148 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
9149 | { |
9150 | struct swevent_hlist *hlist; | |
76e1d904 | 9151 | |
b28ab83c | 9152 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
9153 | if (!hlist) |
9154 | return NULL; | |
9155 | ||
49f135ed FW |
9156 | return __find_swevent_head(hlist, type, event_id); |
9157 | } | |
9158 | ||
9159 | /* For the event head insertion and removal in the hlist */ | |
9160 | static inline struct hlist_head * | |
b28ab83c | 9161 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
9162 | { |
9163 | struct swevent_hlist *hlist; | |
9164 | u32 event_id = event->attr.config; | |
9165 | u64 type = event->attr.type; | |
9166 | ||
9167 | /* | |
9168 | * Event scheduling is always serialized against hlist allocation | |
9169 | * and release. Which makes the protected version suitable here. | |
9170 | * The context lock guarantees that. | |
9171 | */ | |
b28ab83c | 9172 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
9173 | lockdep_is_held(&event->ctx->lock)); |
9174 | if (!hlist) | |
9175 | return NULL; | |
9176 | ||
9177 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
9178 | } |
9179 | ||
9180 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 9181 | u64 nr, |
76e1d904 FW |
9182 | struct perf_sample_data *data, |
9183 | struct pt_regs *regs) | |
15dbf27c | 9184 | { |
4a32fea9 | 9185 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9186 | struct perf_event *event; |
76e1d904 | 9187 | struct hlist_head *head; |
15dbf27c | 9188 | |
76e1d904 | 9189 | rcu_read_lock(); |
b28ab83c | 9190 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
9191 | if (!head) |
9192 | goto end; | |
9193 | ||
b67bfe0d | 9194 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 9195 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 9196 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 9197 | } |
76e1d904 FW |
9198 | end: |
9199 | rcu_read_unlock(); | |
15dbf27c PZ |
9200 | } |
9201 | ||
86038c5e PZI |
9202 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
9203 | ||
4ed7c92d | 9204 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 9205 | { |
4a32fea9 | 9206 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 9207 | |
b28ab83c | 9208 | return get_recursion_context(swhash->recursion); |
96f6d444 | 9209 | } |
645e8cc0 | 9210 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 9211 | |
98b5c2c6 | 9212 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 9213 | { |
4a32fea9 | 9214 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 9215 | |
b28ab83c | 9216 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 9217 | } |
15dbf27c | 9218 | |
86038c5e | 9219 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 9220 | { |
a4234bfc | 9221 | struct perf_sample_data data; |
4ed7c92d | 9222 | |
86038c5e | 9223 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 9224 | return; |
a4234bfc | 9225 | |
fd0d000b | 9226 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 9227 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
9228 | } |
9229 | ||
9230 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
9231 | { | |
9232 | int rctx; | |
9233 | ||
9234 | preempt_disable_notrace(); | |
9235 | rctx = perf_swevent_get_recursion_context(); | |
9236 | if (unlikely(rctx < 0)) | |
9237 | goto fail; | |
9238 | ||
9239 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
9240 | |
9241 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 9242 | fail: |
1c024eca | 9243 | preempt_enable_notrace(); |
b8e83514 PZ |
9244 | } |
9245 | ||
cdd6c482 | 9246 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 9247 | { |
15dbf27c PZ |
9248 | } |
9249 | ||
a4eaf7f1 | 9250 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 9251 | { |
4a32fea9 | 9252 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9253 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
9254 | struct hlist_head *head; |
9255 | ||
6c7e550f | 9256 | if (is_sampling_event(event)) { |
7b4b6658 | 9257 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 9258 | perf_swevent_set_period(event); |
7b4b6658 | 9259 | } |
76e1d904 | 9260 | |
a4eaf7f1 PZ |
9261 | hwc->state = !(flags & PERF_EF_START); |
9262 | ||
b28ab83c | 9263 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9264 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9265 | return -EINVAL; |
9266 | ||
9267 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9268 | perf_event_update_userpage(event); |
76e1d904 | 9269 | |
15dbf27c PZ |
9270 | return 0; |
9271 | } | |
9272 | ||
a4eaf7f1 | 9273 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9274 | { |
76e1d904 | 9275 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9276 | } |
9277 | ||
a4eaf7f1 | 9278 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9279 | { |
a4eaf7f1 | 9280 | event->hw.state = 0; |
d6d020e9 | 9281 | } |
aa9c4c0f | 9282 | |
a4eaf7f1 | 9283 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9284 | { |
a4eaf7f1 | 9285 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9286 | } |
9287 | ||
49f135ed FW |
9288 | /* Deref the hlist from the update side */ |
9289 | static inline struct swevent_hlist * | |
b28ab83c | 9290 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9291 | { |
b28ab83c PZ |
9292 | return rcu_dereference_protected(swhash->swevent_hlist, |
9293 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9294 | } |
9295 | ||
b28ab83c | 9296 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9297 | { |
b28ab83c | 9298 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9299 | |
49f135ed | 9300 | if (!hlist) |
76e1d904 FW |
9301 | return; |
9302 | ||
70691d4a | 9303 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9304 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9305 | } |
9306 | ||
3b364d7b | 9307 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9308 | { |
b28ab83c | 9309 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9310 | |
b28ab83c | 9311 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9312 | |
b28ab83c PZ |
9313 | if (!--swhash->hlist_refcount) |
9314 | swevent_hlist_release(swhash); | |
76e1d904 | 9315 | |
b28ab83c | 9316 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9317 | } |
9318 | ||
3b364d7b | 9319 | static void swevent_hlist_put(void) |
76e1d904 FW |
9320 | { |
9321 | int cpu; | |
9322 | ||
76e1d904 | 9323 | for_each_possible_cpu(cpu) |
3b364d7b | 9324 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9325 | } |
9326 | ||
3b364d7b | 9327 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9328 | { |
b28ab83c | 9329 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9330 | int err = 0; |
9331 | ||
b28ab83c | 9332 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9333 | if (!swevent_hlist_deref(swhash) && |
9334 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9335 | struct swevent_hlist *hlist; |
9336 | ||
9337 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9338 | if (!hlist) { | |
9339 | err = -ENOMEM; | |
9340 | goto exit; | |
9341 | } | |
b28ab83c | 9342 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9343 | } |
b28ab83c | 9344 | swhash->hlist_refcount++; |
9ed6060d | 9345 | exit: |
b28ab83c | 9346 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9347 | |
9348 | return err; | |
9349 | } | |
9350 | ||
3b364d7b | 9351 | static int swevent_hlist_get(void) |
76e1d904 | 9352 | { |
3b364d7b | 9353 | int err, cpu, failed_cpu; |
76e1d904 | 9354 | |
a63fbed7 | 9355 | mutex_lock(&pmus_lock); |
76e1d904 | 9356 | for_each_possible_cpu(cpu) { |
3b364d7b | 9357 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9358 | if (err) { |
9359 | failed_cpu = cpu; | |
9360 | goto fail; | |
9361 | } | |
9362 | } | |
a63fbed7 | 9363 | mutex_unlock(&pmus_lock); |
76e1d904 | 9364 | return 0; |
9ed6060d | 9365 | fail: |
76e1d904 FW |
9366 | for_each_possible_cpu(cpu) { |
9367 | if (cpu == failed_cpu) | |
9368 | break; | |
3b364d7b | 9369 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9370 | } |
a63fbed7 | 9371 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9372 | return err; |
9373 | } | |
9374 | ||
c5905afb | 9375 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9376 | |
b0a873eb PZ |
9377 | static void sw_perf_event_destroy(struct perf_event *event) |
9378 | { | |
9379 | u64 event_id = event->attr.config; | |
95476b64 | 9380 | |
b0a873eb PZ |
9381 | WARN_ON(event->parent); |
9382 | ||
c5905afb | 9383 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9384 | swevent_hlist_put(); |
b0a873eb PZ |
9385 | } |
9386 | ||
9387 | static int perf_swevent_init(struct perf_event *event) | |
9388 | { | |
8176cced | 9389 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9390 | |
9391 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9392 | return -ENOENT; | |
9393 | ||
2481c5fa SE |
9394 | /* |
9395 | * no branch sampling for software events | |
9396 | */ | |
9397 | if (has_branch_stack(event)) | |
9398 | return -EOPNOTSUPP; | |
9399 | ||
b0a873eb PZ |
9400 | switch (event_id) { |
9401 | case PERF_COUNT_SW_CPU_CLOCK: | |
9402 | case PERF_COUNT_SW_TASK_CLOCK: | |
9403 | return -ENOENT; | |
9404 | ||
9405 | default: | |
9406 | break; | |
9407 | } | |
9408 | ||
ce677831 | 9409 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9410 | return -ENOENT; |
9411 | ||
9412 | if (!event->parent) { | |
9413 | int err; | |
9414 | ||
3b364d7b | 9415 | err = swevent_hlist_get(); |
b0a873eb PZ |
9416 | if (err) |
9417 | return err; | |
9418 | ||
c5905afb | 9419 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9420 | event->destroy = sw_perf_event_destroy; |
9421 | } | |
9422 | ||
9423 | return 0; | |
9424 | } | |
9425 | ||
9426 | static struct pmu perf_swevent = { | |
89a1e187 | 9427 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9428 | |
34f43927 PZ |
9429 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9430 | ||
b0a873eb | 9431 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9432 | .add = perf_swevent_add, |
9433 | .del = perf_swevent_del, | |
9434 | .start = perf_swevent_start, | |
9435 | .stop = perf_swevent_stop, | |
1c024eca | 9436 | .read = perf_swevent_read, |
1c024eca PZ |
9437 | }; |
9438 | ||
b0a873eb PZ |
9439 | #ifdef CONFIG_EVENT_TRACING |
9440 | ||
1c024eca PZ |
9441 | static int perf_tp_filter_match(struct perf_event *event, |
9442 | struct perf_sample_data *data) | |
9443 | { | |
7e3f977e | 9444 | void *record = data->raw->frag.data; |
1c024eca | 9445 | |
b71b437e PZ |
9446 | /* only top level events have filters set */ |
9447 | if (event->parent) | |
9448 | event = event->parent; | |
9449 | ||
1c024eca PZ |
9450 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9451 | return 1; | |
9452 | return 0; | |
9453 | } | |
9454 | ||
9455 | static int perf_tp_event_match(struct perf_event *event, | |
9456 | struct perf_sample_data *data, | |
9457 | struct pt_regs *regs) | |
9458 | { | |
a0f7d0f7 FW |
9459 | if (event->hw.state & PERF_HES_STOPPED) |
9460 | return 0; | |
580d607c | 9461 | /* |
9fd2e48b | 9462 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9463 | */ |
9fd2e48b | 9464 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9465 | return 0; |
9466 | ||
9467 | if (!perf_tp_filter_match(event, data)) | |
9468 | return 0; | |
9469 | ||
9470 | return 1; | |
9471 | } | |
9472 | ||
85b67bcb AS |
9473 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9474 | struct trace_event_call *call, u64 count, | |
9475 | struct pt_regs *regs, struct hlist_head *head, | |
9476 | struct task_struct *task) | |
9477 | { | |
e87c6bc3 | 9478 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9479 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9480 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9481 | perf_swevent_put_recursion_context(rctx); |
9482 | return; | |
9483 | } | |
9484 | } | |
9485 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9486 | rctx, task); |
85b67bcb AS |
9487 | } |
9488 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9489 | ||
1e1dcd93 | 9490 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9491 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9492 | struct task_struct *task) |
95476b64 FW |
9493 | { |
9494 | struct perf_sample_data data; | |
8fd0fbbe | 9495 | struct perf_event *event; |
1c024eca | 9496 | |
95476b64 | 9497 | struct perf_raw_record raw = { |
7e3f977e DB |
9498 | .frag = { |
9499 | .size = entry_size, | |
9500 | .data = record, | |
9501 | }, | |
95476b64 FW |
9502 | }; |
9503 | ||
1e1dcd93 | 9504 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9505 | data.raw = &raw; |
9506 | ||
1e1dcd93 AS |
9507 | perf_trace_buf_update(record, event_type); |
9508 | ||
8fd0fbbe | 9509 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9510 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9511 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9512 | } |
ecc55f84 | 9513 | |
e6dab5ff AV |
9514 | /* |
9515 | * If we got specified a target task, also iterate its context and | |
9516 | * deliver this event there too. | |
9517 | */ | |
9518 | if (task && task != current) { | |
9519 | struct perf_event_context *ctx; | |
9520 | struct trace_entry *entry = record; | |
9521 | ||
9522 | rcu_read_lock(); | |
9523 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9524 | if (!ctx) | |
9525 | goto unlock; | |
9526 | ||
9527 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9528 | if (event->cpu != smp_processor_id()) |
9529 | continue; | |
e6dab5ff AV |
9530 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9531 | continue; | |
9532 | if (event->attr.config != entry->type) | |
9533 | continue; | |
9534 | if (perf_tp_event_match(event, &data, regs)) | |
9535 | perf_swevent_event(event, count, &data, regs); | |
9536 | } | |
9537 | unlock: | |
9538 | rcu_read_unlock(); | |
9539 | } | |
9540 | ||
ecc55f84 | 9541 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9542 | } |
9543 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9544 | ||
cdd6c482 | 9545 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9546 | { |
1c024eca | 9547 | perf_trace_destroy(event); |
e077df4f PZ |
9548 | } |
9549 | ||
b0a873eb | 9550 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9551 | { |
76e1d904 FW |
9552 | int err; |
9553 | ||
b0a873eb PZ |
9554 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9555 | return -ENOENT; | |
9556 | ||
2481c5fa SE |
9557 | /* |
9558 | * no branch sampling for tracepoint events | |
9559 | */ | |
9560 | if (has_branch_stack(event)) | |
9561 | return -EOPNOTSUPP; | |
9562 | ||
1c024eca PZ |
9563 | err = perf_trace_init(event); |
9564 | if (err) | |
b0a873eb | 9565 | return err; |
e077df4f | 9566 | |
cdd6c482 | 9567 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9568 | |
b0a873eb PZ |
9569 | return 0; |
9570 | } | |
9571 | ||
9572 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9573 | .task_ctx_nr = perf_sw_context, |
9574 | ||
b0a873eb | 9575 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9576 | .add = perf_trace_add, |
9577 | .del = perf_trace_del, | |
9578 | .start = perf_swevent_start, | |
9579 | .stop = perf_swevent_stop, | |
b0a873eb | 9580 | .read = perf_swevent_read, |
b0a873eb PZ |
9581 | }; |
9582 | ||
33ea4b24 | 9583 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9584 | /* |
9585 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9586 | * The flags should match following PMU_FORMAT_ATTR(). | |
9587 | * | |
9588 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9589 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9590 | * |
9591 | * The following values specify a reference counter (or semaphore in the | |
9592 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9593 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9594 | * | |
9595 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9596 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9597 | */ |
9598 | enum perf_probe_config { | |
9599 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9600 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9601 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9602 | }; |
9603 | ||
9604 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9605 | #endif |
e12f03d7 | 9606 | |
a6ca88b2 SL |
9607 | #ifdef CONFIG_KPROBE_EVENTS |
9608 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9609 | &format_attr_retprobe.attr, |
9610 | NULL, | |
9611 | }; | |
9612 | ||
a6ca88b2 | 9613 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9614 | .name = "format", |
a6ca88b2 | 9615 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9616 | }; |
9617 | ||
a6ca88b2 SL |
9618 | static const struct attribute_group *kprobe_attr_groups[] = { |
9619 | &kprobe_format_group, | |
e12f03d7 SL |
9620 | NULL, |
9621 | }; | |
9622 | ||
9623 | static int perf_kprobe_event_init(struct perf_event *event); | |
9624 | static struct pmu perf_kprobe = { | |
9625 | .task_ctx_nr = perf_sw_context, | |
9626 | .event_init = perf_kprobe_event_init, | |
9627 | .add = perf_trace_add, | |
9628 | .del = perf_trace_del, | |
9629 | .start = perf_swevent_start, | |
9630 | .stop = perf_swevent_stop, | |
9631 | .read = perf_swevent_read, | |
a6ca88b2 | 9632 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9633 | }; |
9634 | ||
9635 | static int perf_kprobe_event_init(struct perf_event *event) | |
9636 | { | |
9637 | int err; | |
9638 | bool is_retprobe; | |
9639 | ||
9640 | if (event->attr.type != perf_kprobe.type) | |
9641 | return -ENOENT; | |
32e6e967 | 9642 | |
c9e0924e | 9643 | if (!perfmon_capable()) |
32e6e967 SL |
9644 | return -EACCES; |
9645 | ||
e12f03d7 SL |
9646 | /* |
9647 | * no branch sampling for probe events | |
9648 | */ | |
9649 | if (has_branch_stack(event)) | |
9650 | return -EOPNOTSUPP; | |
9651 | ||
9652 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9653 | err = perf_kprobe_init(event, is_retprobe); | |
9654 | if (err) | |
9655 | return err; | |
9656 | ||
9657 | event->destroy = perf_kprobe_destroy; | |
9658 | ||
9659 | return 0; | |
9660 | } | |
9661 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9662 | ||
33ea4b24 | 9663 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9664 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9665 | ||
9666 | static struct attribute *uprobe_attrs[] = { | |
9667 | &format_attr_retprobe.attr, | |
9668 | &format_attr_ref_ctr_offset.attr, | |
9669 | NULL, | |
9670 | }; | |
9671 | ||
9672 | static struct attribute_group uprobe_format_group = { | |
9673 | .name = "format", | |
9674 | .attrs = uprobe_attrs, | |
9675 | }; | |
9676 | ||
9677 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9678 | &uprobe_format_group, | |
9679 | NULL, | |
9680 | }; | |
9681 | ||
33ea4b24 SL |
9682 | static int perf_uprobe_event_init(struct perf_event *event); |
9683 | static struct pmu perf_uprobe = { | |
9684 | .task_ctx_nr = perf_sw_context, | |
9685 | .event_init = perf_uprobe_event_init, | |
9686 | .add = perf_trace_add, | |
9687 | .del = perf_trace_del, | |
9688 | .start = perf_swevent_start, | |
9689 | .stop = perf_swevent_stop, | |
9690 | .read = perf_swevent_read, | |
a6ca88b2 | 9691 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9692 | }; |
9693 | ||
9694 | static int perf_uprobe_event_init(struct perf_event *event) | |
9695 | { | |
9696 | int err; | |
a6ca88b2 | 9697 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9698 | bool is_retprobe; |
9699 | ||
9700 | if (event->attr.type != perf_uprobe.type) | |
9701 | return -ENOENT; | |
32e6e967 | 9702 | |
c9e0924e | 9703 | if (!perfmon_capable()) |
32e6e967 SL |
9704 | return -EACCES; |
9705 | ||
33ea4b24 SL |
9706 | /* |
9707 | * no branch sampling for probe events | |
9708 | */ | |
9709 | if (has_branch_stack(event)) | |
9710 | return -EOPNOTSUPP; | |
9711 | ||
9712 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9713 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9714 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9715 | if (err) |
9716 | return err; | |
9717 | ||
9718 | event->destroy = perf_uprobe_destroy; | |
9719 | ||
9720 | return 0; | |
9721 | } | |
9722 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9723 | ||
b0a873eb PZ |
9724 | static inline void perf_tp_register(void) |
9725 | { | |
2e80a82a | 9726 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9727 | #ifdef CONFIG_KPROBE_EVENTS |
9728 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9729 | #endif | |
33ea4b24 SL |
9730 | #ifdef CONFIG_UPROBE_EVENTS |
9731 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9732 | #endif | |
e077df4f | 9733 | } |
6fb2915d | 9734 | |
6fb2915d LZ |
9735 | static void perf_event_free_filter(struct perf_event *event) |
9736 | { | |
9737 | ftrace_profile_free_filter(event); | |
9738 | } | |
9739 | ||
aa6a5f3c AS |
9740 | #ifdef CONFIG_BPF_SYSCALL |
9741 | static void bpf_overflow_handler(struct perf_event *event, | |
9742 | struct perf_sample_data *data, | |
9743 | struct pt_regs *regs) | |
9744 | { | |
9745 | struct bpf_perf_event_data_kern ctx = { | |
9746 | .data = data, | |
7d9285e8 | 9747 | .event = event, |
aa6a5f3c AS |
9748 | }; |
9749 | int ret = 0; | |
9750 | ||
c895f6f7 | 9751 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9752 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9753 | goto out; | |
9754 | rcu_read_lock(); | |
88575199 | 9755 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9756 | rcu_read_unlock(); |
9757 | out: | |
9758 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9759 | if (!ret) |
9760 | return; | |
9761 | ||
9762 | event->orig_overflow_handler(event, data, regs); | |
9763 | } | |
9764 | ||
9765 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9766 | { | |
9767 | struct bpf_prog *prog; | |
9768 | ||
9769 | if (event->overflow_handler_context) | |
9770 | /* hw breakpoint or kernel counter */ | |
9771 | return -EINVAL; | |
9772 | ||
9773 | if (event->prog) | |
9774 | return -EEXIST; | |
9775 | ||
9776 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9777 | if (IS_ERR(prog)) | |
9778 | return PTR_ERR(prog); | |
9779 | ||
5d99cb2c SL |
9780 | if (event->attr.precise_ip && |
9781 | prog->call_get_stack && | |
9782 | (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY) || | |
9783 | event->attr.exclude_callchain_kernel || | |
9784 | event->attr.exclude_callchain_user)) { | |
9785 | /* | |
9786 | * On perf_event with precise_ip, calling bpf_get_stack() | |
9787 | * may trigger unwinder warnings and occasional crashes. | |
9788 | * bpf_get_[stack|stackid] works around this issue by using | |
9789 | * callchain attached to perf_sample_data. If the | |
9790 | * perf_event does not full (kernel and user) callchain | |
9791 | * attached to perf_sample_data, do not allow attaching BPF | |
9792 | * program that calls bpf_get_[stack|stackid]. | |
9793 | */ | |
9794 | bpf_prog_put(prog); | |
9795 | return -EPROTO; | |
9796 | } | |
9797 | ||
aa6a5f3c AS |
9798 | event->prog = prog; |
9799 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9800 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9801 | return 0; | |
9802 | } | |
9803 | ||
9804 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9805 | { | |
9806 | struct bpf_prog *prog = event->prog; | |
9807 | ||
9808 | if (!prog) | |
9809 | return; | |
9810 | ||
9811 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9812 | event->prog = NULL; | |
9813 | bpf_prog_put(prog); | |
9814 | } | |
9815 | #else | |
9816 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9817 | { | |
9818 | return -EOPNOTSUPP; | |
9819 | } | |
9820 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9821 | { | |
9822 | } | |
9823 | #endif | |
9824 | ||
e12f03d7 SL |
9825 | /* |
9826 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9827 | * with perf_event_open() | |
9828 | */ | |
9829 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9830 | { | |
9831 | if (event->pmu == &perf_tracepoint) | |
9832 | return true; | |
9833 | #ifdef CONFIG_KPROBE_EVENTS | |
9834 | if (event->pmu == &perf_kprobe) | |
9835 | return true; | |
33ea4b24 SL |
9836 | #endif |
9837 | #ifdef CONFIG_UPROBE_EVENTS | |
9838 | if (event->pmu == &perf_uprobe) | |
9839 | return true; | |
e12f03d7 SL |
9840 | #endif |
9841 | return false; | |
9842 | } | |
9843 | ||
2541517c AS |
9844 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9845 | { | |
cf5f5cea | 9846 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9847 | struct bpf_prog *prog; |
e87c6bc3 | 9848 | int ret; |
2541517c | 9849 | |
e12f03d7 | 9850 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9851 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9852 | |
98b5c2c6 AS |
9853 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9854 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9855 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9856 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9857 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9858 | return -EINVAL; |
9859 | ||
9860 | prog = bpf_prog_get(prog_fd); | |
9861 | if (IS_ERR(prog)) | |
9862 | return PTR_ERR(prog); | |
9863 | ||
98b5c2c6 | 9864 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9865 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9866 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9867 | /* valid fd, but invalid bpf program type */ |
9868 | bpf_prog_put(prog); | |
9869 | return -EINVAL; | |
9870 | } | |
9871 | ||
9802d865 JB |
9872 | /* Kprobe override only works for kprobes, not uprobes. */ |
9873 | if (prog->kprobe_override && | |
9874 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9875 | bpf_prog_put(prog); | |
9876 | return -EINVAL; | |
9877 | } | |
9878 | ||
cf5f5cea | 9879 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9880 | int off = trace_event_get_offsets(event->tp_event); |
9881 | ||
9882 | if (prog->aux->max_ctx_offset > off) { | |
9883 | bpf_prog_put(prog); | |
9884 | return -EACCES; | |
9885 | } | |
9886 | } | |
2541517c | 9887 | |
e87c6bc3 YS |
9888 | ret = perf_event_attach_bpf_prog(event, prog); |
9889 | if (ret) | |
9890 | bpf_prog_put(prog); | |
9891 | return ret; | |
2541517c AS |
9892 | } |
9893 | ||
9894 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9895 | { | |
e12f03d7 | 9896 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9897 | perf_event_free_bpf_handler(event); |
2541517c | 9898 | return; |
2541517c | 9899 | } |
e87c6bc3 | 9900 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9901 | } |
9902 | ||
e077df4f | 9903 | #else |
6fb2915d | 9904 | |
b0a873eb | 9905 | static inline void perf_tp_register(void) |
e077df4f | 9906 | { |
e077df4f | 9907 | } |
6fb2915d | 9908 | |
6fb2915d LZ |
9909 | static void perf_event_free_filter(struct perf_event *event) |
9910 | { | |
9911 | } | |
9912 | ||
2541517c AS |
9913 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9914 | { | |
9915 | return -ENOENT; | |
9916 | } | |
9917 | ||
9918 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9919 | { | |
9920 | } | |
07b139c8 | 9921 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9922 | |
24f1e32c | 9923 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9924 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9925 | { |
f5ffe02e FW |
9926 | struct perf_sample_data sample; |
9927 | struct pt_regs *regs = data; | |
9928 | ||
fd0d000b | 9929 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9930 | |
a4eaf7f1 | 9931 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9932 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9933 | } |
9934 | #endif | |
9935 | ||
375637bc AS |
9936 | /* |
9937 | * Allocate a new address filter | |
9938 | */ | |
9939 | static struct perf_addr_filter * | |
9940 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9941 | { | |
9942 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9943 | struct perf_addr_filter *filter; | |
9944 | ||
9945 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9946 | if (!filter) | |
9947 | return NULL; | |
9948 | ||
9949 | INIT_LIST_HEAD(&filter->entry); | |
9950 | list_add_tail(&filter->entry, filters); | |
9951 | ||
9952 | return filter; | |
9953 | } | |
9954 | ||
9955 | static void free_filters_list(struct list_head *filters) | |
9956 | { | |
9957 | struct perf_addr_filter *filter, *iter; | |
9958 | ||
9959 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9960 | path_put(&filter->path); |
375637bc AS |
9961 | list_del(&filter->entry); |
9962 | kfree(filter); | |
9963 | } | |
9964 | } | |
9965 | ||
9966 | /* | |
9967 | * Free existing address filters and optionally install new ones | |
9968 | */ | |
9969 | static void perf_addr_filters_splice(struct perf_event *event, | |
9970 | struct list_head *head) | |
9971 | { | |
9972 | unsigned long flags; | |
9973 | LIST_HEAD(list); | |
9974 | ||
9975 | if (!has_addr_filter(event)) | |
9976 | return; | |
9977 | ||
9978 | /* don't bother with children, they don't have their own filters */ | |
9979 | if (event->parent) | |
9980 | return; | |
9981 | ||
9982 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9983 | ||
9984 | list_splice_init(&event->addr_filters.list, &list); | |
9985 | if (head) | |
9986 | list_splice(head, &event->addr_filters.list); | |
9987 | ||
9988 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9989 | ||
9990 | free_filters_list(&list); | |
9991 | } | |
9992 | ||
9993 | /* | |
9994 | * Scan through mm's vmas and see if one of them matches the | |
9995 | * @filter; if so, adjust filter's address range. | |
c1e8d7c6 | 9996 | * Called with mm::mmap_lock down for reading. |
375637bc | 9997 | */ |
c60f83b8 AS |
9998 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9999 | struct mm_struct *mm, | |
10000 | struct perf_addr_filter_range *fr) | |
375637bc AS |
10001 | { |
10002 | struct vm_area_struct *vma; | |
10003 | ||
10004 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 10005 | if (!vma->vm_file) |
375637bc AS |
10006 | continue; |
10007 | ||
c60f83b8 AS |
10008 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
10009 | return; | |
375637bc | 10010 | } |
375637bc AS |
10011 | } |
10012 | ||
10013 | /* | |
10014 | * Update event's address range filters based on the | |
10015 | * task's existing mappings, if any. | |
10016 | */ | |
10017 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
10018 | { | |
10019 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10020 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
10021 | struct perf_addr_filter *filter; | |
10022 | struct mm_struct *mm = NULL; | |
10023 | unsigned int count = 0; | |
10024 | unsigned long flags; | |
10025 | ||
10026 | /* | |
10027 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
10028 | * will stop on the parent's child_mutex that our caller is also holding | |
10029 | */ | |
10030 | if (task == TASK_TOMBSTONE) | |
10031 | return; | |
10032 | ||
52a44f83 AS |
10033 | if (ifh->nr_file_filters) { |
10034 | mm = get_task_mm(event->ctx->task); | |
10035 | if (!mm) | |
10036 | goto restart; | |
375637bc | 10037 | |
d8ed45c5 | 10038 | mmap_read_lock(mm); |
52a44f83 | 10039 | } |
375637bc AS |
10040 | |
10041 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
10042 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
10043 | if (filter->path.dentry) { |
10044 | /* | |
10045 | * Adjust base offset if the filter is associated to a | |
10046 | * binary that needs to be mapped: | |
10047 | */ | |
10048 | event->addr_filter_ranges[count].start = 0; | |
10049 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 10050 | |
c60f83b8 | 10051 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
10052 | } else { |
10053 | event->addr_filter_ranges[count].start = filter->offset; | |
10054 | event->addr_filter_ranges[count].size = filter->size; | |
10055 | } | |
375637bc AS |
10056 | |
10057 | count++; | |
10058 | } | |
10059 | ||
10060 | event->addr_filters_gen++; | |
10061 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
10062 | ||
52a44f83 | 10063 | if (ifh->nr_file_filters) { |
d8ed45c5 | 10064 | mmap_read_unlock(mm); |
375637bc | 10065 | |
52a44f83 AS |
10066 | mmput(mm); |
10067 | } | |
375637bc AS |
10068 | |
10069 | restart: | |
767ae086 | 10070 | perf_event_stop(event, 1); |
375637bc AS |
10071 | } |
10072 | ||
10073 | /* | |
10074 | * Address range filtering: limiting the data to certain | |
10075 | * instruction address ranges. Filters are ioctl()ed to us from | |
10076 | * userspace as ascii strings. | |
10077 | * | |
10078 | * Filter string format: | |
10079 | * | |
10080 | * ACTION RANGE_SPEC | |
10081 | * where ACTION is one of the | |
10082 | * * "filter": limit the trace to this region | |
10083 | * * "start": start tracing from this address | |
10084 | * * "stop": stop tracing at this address/region; | |
10085 | * RANGE_SPEC is | |
10086 | * * for kernel addresses: <start address>[/<size>] | |
10087 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
10088 | * | |
6ed70cf3 AS |
10089 | * if <size> is not specified or is zero, the range is treated as a single |
10090 | * address; not valid for ACTION=="filter". | |
375637bc AS |
10091 | */ |
10092 | enum { | |
e96271f3 | 10093 | IF_ACT_NONE = -1, |
375637bc AS |
10094 | IF_ACT_FILTER, |
10095 | IF_ACT_START, | |
10096 | IF_ACT_STOP, | |
10097 | IF_SRC_FILE, | |
10098 | IF_SRC_KERNEL, | |
10099 | IF_SRC_FILEADDR, | |
10100 | IF_SRC_KERNELADDR, | |
10101 | }; | |
10102 | ||
10103 | enum { | |
10104 | IF_STATE_ACTION = 0, | |
10105 | IF_STATE_SOURCE, | |
10106 | IF_STATE_END, | |
10107 | }; | |
10108 | ||
10109 | static const match_table_t if_tokens = { | |
10110 | { IF_ACT_FILTER, "filter" }, | |
10111 | { IF_ACT_START, "start" }, | |
10112 | { IF_ACT_STOP, "stop" }, | |
10113 | { IF_SRC_FILE, "%u/%u@%s" }, | |
10114 | { IF_SRC_KERNEL, "%u/%u" }, | |
10115 | { IF_SRC_FILEADDR, "%u@%s" }, | |
10116 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 10117 | { IF_ACT_NONE, NULL }, |
375637bc AS |
10118 | }; |
10119 | ||
10120 | /* | |
10121 | * Address filter string parser | |
10122 | */ | |
10123 | static int | |
10124 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
10125 | struct list_head *filters) | |
10126 | { | |
10127 | struct perf_addr_filter *filter = NULL; | |
10128 | char *start, *orig, *filename = NULL; | |
375637bc AS |
10129 | substring_t args[MAX_OPT_ARGS]; |
10130 | int state = IF_STATE_ACTION, token; | |
10131 | unsigned int kernel = 0; | |
10132 | int ret = -EINVAL; | |
10133 | ||
10134 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
10135 | if (!fstr) | |
10136 | return -ENOMEM; | |
10137 | ||
10138 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
10139 | static const enum perf_addr_filter_action_t actions[] = { |
10140 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
10141 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
10142 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
10143 | }; | |
375637bc AS |
10144 | ret = -EINVAL; |
10145 | ||
10146 | if (!*start) | |
10147 | continue; | |
10148 | ||
10149 | /* filter definition begins */ | |
10150 | if (state == IF_STATE_ACTION) { | |
10151 | filter = perf_addr_filter_new(event, filters); | |
10152 | if (!filter) | |
10153 | goto fail; | |
10154 | } | |
10155 | ||
10156 | token = match_token(start, if_tokens, args); | |
10157 | switch (token) { | |
10158 | case IF_ACT_FILTER: | |
10159 | case IF_ACT_START: | |
375637bc AS |
10160 | case IF_ACT_STOP: |
10161 | if (state != IF_STATE_ACTION) | |
10162 | goto fail; | |
10163 | ||
6ed70cf3 | 10164 | filter->action = actions[token]; |
375637bc AS |
10165 | state = IF_STATE_SOURCE; |
10166 | break; | |
10167 | ||
10168 | case IF_SRC_KERNELADDR: | |
10169 | case IF_SRC_KERNEL: | |
10170 | kernel = 1; | |
df561f66 | 10171 | fallthrough; |
375637bc AS |
10172 | |
10173 | case IF_SRC_FILEADDR: | |
10174 | case IF_SRC_FILE: | |
10175 | if (state != IF_STATE_SOURCE) | |
10176 | goto fail; | |
10177 | ||
375637bc AS |
10178 | *args[0].to = 0; |
10179 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
10180 | if (ret) | |
10181 | goto fail; | |
10182 | ||
6ed70cf3 | 10183 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
10184 | *args[1].to = 0; |
10185 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
10186 | if (ret) | |
10187 | goto fail; | |
10188 | } | |
10189 | ||
4059ffd0 | 10190 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 10191 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 | 10192 | |
7bdb157c | 10193 | kfree(filename); |
4059ffd0 | 10194 | filename = match_strdup(&args[fpos]); |
375637bc AS |
10195 | if (!filename) { |
10196 | ret = -ENOMEM; | |
10197 | goto fail; | |
10198 | } | |
10199 | } | |
10200 | ||
10201 | state = IF_STATE_END; | |
10202 | break; | |
10203 | ||
10204 | default: | |
10205 | goto fail; | |
10206 | } | |
10207 | ||
10208 | /* | |
10209 | * Filter definition is fully parsed, validate and install it. | |
10210 | * Make sure that it doesn't contradict itself or the event's | |
10211 | * attribute. | |
10212 | */ | |
10213 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 10214 | ret = -EINVAL; |
375637bc AS |
10215 | if (kernel && event->attr.exclude_kernel) |
10216 | goto fail; | |
10217 | ||
6ed70cf3 AS |
10218 | /* |
10219 | * ACTION "filter" must have a non-zero length region | |
10220 | * specified. | |
10221 | */ | |
10222 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
10223 | !filter->size) | |
10224 | goto fail; | |
10225 | ||
375637bc AS |
10226 | if (!kernel) { |
10227 | if (!filename) | |
10228 | goto fail; | |
10229 | ||
6ce77bfd AS |
10230 | /* |
10231 | * For now, we only support file-based filters | |
10232 | * in per-task events; doing so for CPU-wide | |
10233 | * events requires additional context switching | |
10234 | * trickery, since same object code will be | |
10235 | * mapped at different virtual addresses in | |
10236 | * different processes. | |
10237 | */ | |
10238 | ret = -EOPNOTSUPP; | |
10239 | if (!event->ctx->task) | |
7bdb157c | 10240 | goto fail; |
6ce77bfd | 10241 | |
375637bc | 10242 | /* look up the path and grab its inode */ |
9511bce9 SL |
10243 | ret = kern_path(filename, LOOKUP_FOLLOW, |
10244 | &filter->path); | |
375637bc | 10245 | if (ret) |
7bdb157c | 10246 | goto fail; |
375637bc AS |
10247 | |
10248 | ret = -EINVAL; | |
9511bce9 SL |
10249 | if (!filter->path.dentry || |
10250 | !S_ISREG(d_inode(filter->path.dentry) | |
10251 | ->i_mode)) | |
375637bc | 10252 | goto fail; |
6ce77bfd AS |
10253 | |
10254 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
10255 | } |
10256 | ||
10257 | /* ready to consume more filters */ | |
10258 | state = IF_STATE_ACTION; | |
10259 | filter = NULL; | |
10260 | } | |
10261 | } | |
10262 | ||
10263 | if (state != IF_STATE_ACTION) | |
10264 | goto fail; | |
10265 | ||
7bdb157c | 10266 | kfree(filename); |
375637bc AS |
10267 | kfree(orig); |
10268 | ||
10269 | return 0; | |
10270 | ||
375637bc | 10271 | fail: |
7bdb157c | 10272 | kfree(filename); |
375637bc AS |
10273 | free_filters_list(filters); |
10274 | kfree(orig); | |
10275 | ||
10276 | return ret; | |
10277 | } | |
10278 | ||
10279 | static int | |
10280 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10281 | { | |
10282 | LIST_HEAD(filters); | |
10283 | int ret; | |
10284 | ||
10285 | /* | |
10286 | * Since this is called in perf_ioctl() path, we're already holding | |
10287 | * ctx::mutex. | |
10288 | */ | |
10289 | lockdep_assert_held(&event->ctx->mutex); | |
10290 | ||
10291 | if (WARN_ON_ONCE(event->parent)) | |
10292 | return -EINVAL; | |
10293 | ||
375637bc AS |
10294 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10295 | if (ret) | |
6ce77bfd | 10296 | goto fail_clear_files; |
375637bc AS |
10297 | |
10298 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10299 | if (ret) |
10300 | goto fail_free_filters; | |
375637bc AS |
10301 | |
10302 | /* remove existing filters, if any */ | |
10303 | perf_addr_filters_splice(event, &filters); | |
10304 | ||
10305 | /* install new filters */ | |
10306 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10307 | ||
6ce77bfd AS |
10308 | return ret; |
10309 | ||
10310 | fail_free_filters: | |
10311 | free_filters_list(&filters); | |
10312 | ||
10313 | fail_clear_files: | |
10314 | event->addr_filters.nr_file_filters = 0; | |
10315 | ||
375637bc AS |
10316 | return ret; |
10317 | } | |
10318 | ||
c796bbbe AS |
10319 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10320 | { | |
c796bbbe | 10321 | int ret = -EINVAL; |
e12f03d7 | 10322 | char *filter_str; |
c796bbbe AS |
10323 | |
10324 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10325 | if (IS_ERR(filter_str)) | |
10326 | return PTR_ERR(filter_str); | |
10327 | ||
e12f03d7 SL |
10328 | #ifdef CONFIG_EVENT_TRACING |
10329 | if (perf_event_is_tracing(event)) { | |
10330 | struct perf_event_context *ctx = event->ctx; | |
10331 | ||
10332 | /* | |
10333 | * Beware, here be dragons!! | |
10334 | * | |
10335 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10336 | * the tracepoint stuff does not actually need it. So | |
10337 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10338 | * already have a reference on ctx. | |
10339 | * | |
10340 | * This can result in event getting moved to a different ctx, | |
10341 | * but that does not affect the tracepoint state. | |
10342 | */ | |
10343 | mutex_unlock(&ctx->mutex); | |
10344 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10345 | mutex_lock(&ctx->mutex); | |
10346 | } else | |
10347 | #endif | |
10348 | if (has_addr_filter(event)) | |
375637bc | 10349 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10350 | |
10351 | kfree(filter_str); | |
10352 | return ret; | |
10353 | } | |
10354 | ||
b0a873eb PZ |
10355 | /* |
10356 | * hrtimer based swevent callback | |
10357 | */ | |
f29ac756 | 10358 | |
b0a873eb | 10359 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10360 | { |
b0a873eb PZ |
10361 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10362 | struct perf_sample_data data; | |
10363 | struct pt_regs *regs; | |
10364 | struct perf_event *event; | |
10365 | u64 period; | |
f29ac756 | 10366 | |
b0a873eb | 10367 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10368 | |
10369 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10370 | return HRTIMER_NORESTART; | |
10371 | ||
b0a873eb | 10372 | event->pmu->read(event); |
f344011c | 10373 | |
fd0d000b | 10374 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10375 | regs = get_irq_regs(); |
10376 | ||
10377 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10378 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10379 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10380 | ret = HRTIMER_NORESTART; |
10381 | } | |
24f1e32c | 10382 | |
b0a873eb PZ |
10383 | period = max_t(u64, 10000, event->hw.sample_period); |
10384 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10385 | |
b0a873eb | 10386 | return ret; |
f29ac756 PZ |
10387 | } |
10388 | ||
b0a873eb | 10389 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10390 | { |
b0a873eb | 10391 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10392 | s64 period; |
10393 | ||
10394 | if (!is_sampling_event(event)) | |
10395 | return; | |
f5ffe02e | 10396 | |
5d508e82 FBH |
10397 | period = local64_read(&hwc->period_left); |
10398 | if (period) { | |
10399 | if (period < 0) | |
10400 | period = 10000; | |
fa407f35 | 10401 | |
5d508e82 FBH |
10402 | local64_set(&hwc->period_left, 0); |
10403 | } else { | |
10404 | period = max_t(u64, 10000, hwc->sample_period); | |
10405 | } | |
3497d206 | 10406 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10407 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10408 | } |
b0a873eb PZ |
10409 | |
10410 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10411 | { |
b0a873eb PZ |
10412 | struct hw_perf_event *hwc = &event->hw; |
10413 | ||
6c7e550f | 10414 | if (is_sampling_event(event)) { |
b0a873eb | 10415 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10416 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10417 | |
10418 | hrtimer_cancel(&hwc->hrtimer); | |
10419 | } | |
24f1e32c FW |
10420 | } |
10421 | ||
ba3dd36c PZ |
10422 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10423 | { | |
10424 | struct hw_perf_event *hwc = &event->hw; | |
10425 | ||
10426 | if (!is_sampling_event(event)) | |
10427 | return; | |
10428 | ||
30f9028b | 10429 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10430 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10431 | ||
10432 | /* | |
10433 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10434 | * mapping and avoid the whole period adjust feedback stuff. | |
10435 | */ | |
10436 | if (event->attr.freq) { | |
10437 | long freq = event->attr.sample_freq; | |
10438 | ||
10439 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10440 | hwc->sample_period = event->attr.sample_period; | |
10441 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10442 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10443 | event->attr.freq = 0; |
10444 | } | |
10445 | } | |
10446 | ||
b0a873eb PZ |
10447 | /* |
10448 | * Software event: cpu wall time clock | |
10449 | */ | |
10450 | ||
10451 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10452 | { |
b0a873eb PZ |
10453 | s64 prev; |
10454 | u64 now; | |
10455 | ||
a4eaf7f1 | 10456 | now = local_clock(); |
b0a873eb PZ |
10457 | prev = local64_xchg(&event->hw.prev_count, now); |
10458 | local64_add(now - prev, &event->count); | |
24f1e32c | 10459 | } |
24f1e32c | 10460 | |
a4eaf7f1 | 10461 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10462 | { |
a4eaf7f1 | 10463 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10464 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10465 | } |
10466 | ||
a4eaf7f1 | 10467 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10468 | { |
b0a873eb PZ |
10469 | perf_swevent_cancel_hrtimer(event); |
10470 | cpu_clock_event_update(event); | |
10471 | } | |
f29ac756 | 10472 | |
a4eaf7f1 PZ |
10473 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10474 | { | |
10475 | if (flags & PERF_EF_START) | |
10476 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10477 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10478 | |
10479 | return 0; | |
10480 | } | |
10481 | ||
10482 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10483 | { | |
10484 | cpu_clock_event_stop(event, flags); | |
10485 | } | |
10486 | ||
b0a873eb PZ |
10487 | static void cpu_clock_event_read(struct perf_event *event) |
10488 | { | |
10489 | cpu_clock_event_update(event); | |
10490 | } | |
f344011c | 10491 | |
b0a873eb PZ |
10492 | static int cpu_clock_event_init(struct perf_event *event) |
10493 | { | |
10494 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10495 | return -ENOENT; | |
10496 | ||
10497 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10498 | return -ENOENT; | |
10499 | ||
2481c5fa SE |
10500 | /* |
10501 | * no branch sampling for software events | |
10502 | */ | |
10503 | if (has_branch_stack(event)) | |
10504 | return -EOPNOTSUPP; | |
10505 | ||
ba3dd36c PZ |
10506 | perf_swevent_init_hrtimer(event); |
10507 | ||
b0a873eb | 10508 | return 0; |
f29ac756 PZ |
10509 | } |
10510 | ||
b0a873eb | 10511 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10512 | .task_ctx_nr = perf_sw_context, |
10513 | ||
34f43927 PZ |
10514 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10515 | ||
b0a873eb | 10516 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10517 | .add = cpu_clock_event_add, |
10518 | .del = cpu_clock_event_del, | |
10519 | .start = cpu_clock_event_start, | |
10520 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10521 | .read = cpu_clock_event_read, |
10522 | }; | |
10523 | ||
10524 | /* | |
10525 | * Software event: task time clock | |
10526 | */ | |
10527 | ||
10528 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10529 | { |
b0a873eb PZ |
10530 | u64 prev; |
10531 | s64 delta; | |
5c92d124 | 10532 | |
b0a873eb PZ |
10533 | prev = local64_xchg(&event->hw.prev_count, now); |
10534 | delta = now - prev; | |
10535 | local64_add(delta, &event->count); | |
10536 | } | |
5c92d124 | 10537 | |
a4eaf7f1 | 10538 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10539 | { |
a4eaf7f1 | 10540 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10541 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10542 | } |
10543 | ||
a4eaf7f1 | 10544 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10545 | { |
10546 | perf_swevent_cancel_hrtimer(event); | |
10547 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10548 | } |
10549 | ||
10550 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10551 | { | |
10552 | if (flags & PERF_EF_START) | |
10553 | task_clock_event_start(event, flags); | |
6a694a60 | 10554 | perf_event_update_userpage(event); |
b0a873eb | 10555 | |
a4eaf7f1 PZ |
10556 | return 0; |
10557 | } | |
10558 | ||
10559 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10560 | { | |
10561 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10562 | } |
10563 | ||
10564 | static void task_clock_event_read(struct perf_event *event) | |
10565 | { | |
768a06e2 PZ |
10566 | u64 now = perf_clock(); |
10567 | u64 delta = now - event->ctx->timestamp; | |
10568 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10569 | |
10570 | task_clock_event_update(event, time); | |
10571 | } | |
10572 | ||
10573 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10574 | { |
b0a873eb PZ |
10575 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10576 | return -ENOENT; | |
10577 | ||
10578 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10579 | return -ENOENT; | |
10580 | ||
2481c5fa SE |
10581 | /* |
10582 | * no branch sampling for software events | |
10583 | */ | |
10584 | if (has_branch_stack(event)) | |
10585 | return -EOPNOTSUPP; | |
10586 | ||
ba3dd36c PZ |
10587 | perf_swevent_init_hrtimer(event); |
10588 | ||
b0a873eb | 10589 | return 0; |
6fb2915d LZ |
10590 | } |
10591 | ||
b0a873eb | 10592 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10593 | .task_ctx_nr = perf_sw_context, |
10594 | ||
34f43927 PZ |
10595 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10596 | ||
b0a873eb | 10597 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10598 | .add = task_clock_event_add, |
10599 | .del = task_clock_event_del, | |
10600 | .start = task_clock_event_start, | |
10601 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10602 | .read = task_clock_event_read, |
10603 | }; | |
6fb2915d | 10604 | |
ad5133b7 | 10605 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10606 | { |
e077df4f | 10607 | } |
6fb2915d | 10608 | |
fbbe0701 SB |
10609 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10610 | { | |
10611 | } | |
10612 | ||
ad5133b7 | 10613 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10614 | { |
ad5133b7 | 10615 | return 0; |
6fb2915d LZ |
10616 | } |
10617 | ||
81ec3f3c JO |
10618 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10619 | { | |
10620 | return 0; | |
10621 | } | |
10622 | ||
18ab2cd3 | 10623 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10624 | |
10625 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10626 | { |
fbbe0701 SB |
10627 | __this_cpu_write(nop_txn_flags, flags); |
10628 | ||
10629 | if (flags & ~PERF_PMU_TXN_ADD) | |
10630 | return; | |
10631 | ||
ad5133b7 | 10632 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10633 | } |
10634 | ||
ad5133b7 PZ |
10635 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10636 | { | |
fbbe0701 SB |
10637 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10638 | ||
10639 | __this_cpu_write(nop_txn_flags, 0); | |
10640 | ||
10641 | if (flags & ~PERF_PMU_TXN_ADD) | |
10642 | return 0; | |
10643 | ||
ad5133b7 PZ |
10644 | perf_pmu_enable(pmu); |
10645 | return 0; | |
10646 | } | |
e077df4f | 10647 | |
ad5133b7 | 10648 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10649 | { |
fbbe0701 SB |
10650 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10651 | ||
10652 | __this_cpu_write(nop_txn_flags, 0); | |
10653 | ||
10654 | if (flags & ~PERF_PMU_TXN_ADD) | |
10655 | return; | |
10656 | ||
ad5133b7 | 10657 | perf_pmu_enable(pmu); |
24f1e32c FW |
10658 | } |
10659 | ||
35edc2a5 PZ |
10660 | static int perf_event_idx_default(struct perf_event *event) |
10661 | { | |
c719f560 | 10662 | return 0; |
35edc2a5 PZ |
10663 | } |
10664 | ||
8dc85d54 PZ |
10665 | /* |
10666 | * Ensures all contexts with the same task_ctx_nr have the same | |
10667 | * pmu_cpu_context too. | |
10668 | */ | |
9e317041 | 10669 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10670 | { |
8dc85d54 | 10671 | struct pmu *pmu; |
b326e956 | 10672 | |
8dc85d54 PZ |
10673 | if (ctxn < 0) |
10674 | return NULL; | |
24f1e32c | 10675 | |
8dc85d54 PZ |
10676 | list_for_each_entry(pmu, &pmus, entry) { |
10677 | if (pmu->task_ctx_nr == ctxn) | |
10678 | return pmu->pmu_cpu_context; | |
10679 | } | |
24f1e32c | 10680 | |
8dc85d54 | 10681 | return NULL; |
24f1e32c FW |
10682 | } |
10683 | ||
51676957 PZ |
10684 | static void free_pmu_context(struct pmu *pmu) |
10685 | { | |
df0062b2 WD |
10686 | /* |
10687 | * Static contexts such as perf_sw_context have a global lifetime | |
10688 | * and may be shared between different PMUs. Avoid freeing them | |
10689 | * when a single PMU is going away. | |
10690 | */ | |
10691 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10692 | return; | |
10693 | ||
51676957 | 10694 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10695 | } |
6e855cd4 AS |
10696 | |
10697 | /* | |
10698 | * Let userspace know that this PMU supports address range filtering: | |
10699 | */ | |
10700 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10701 | struct device_attribute *attr, | |
10702 | char *page) | |
10703 | { | |
10704 | struct pmu *pmu = dev_get_drvdata(dev); | |
10705 | ||
10706 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10707 | } | |
10708 | DEVICE_ATTR_RO(nr_addr_filters); | |
10709 | ||
2e80a82a | 10710 | static struct idr pmu_idr; |
d6d020e9 | 10711 | |
abe43400 PZ |
10712 | static ssize_t |
10713 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10714 | { | |
10715 | struct pmu *pmu = dev_get_drvdata(dev); | |
10716 | ||
10717 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10718 | } | |
90826ca7 | 10719 | static DEVICE_ATTR_RO(type); |
abe43400 | 10720 | |
62b85639 SE |
10721 | static ssize_t |
10722 | perf_event_mux_interval_ms_show(struct device *dev, | |
10723 | struct device_attribute *attr, | |
10724 | char *page) | |
10725 | { | |
10726 | struct pmu *pmu = dev_get_drvdata(dev); | |
10727 | ||
10728 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10729 | } | |
10730 | ||
272325c4 PZ |
10731 | static DEFINE_MUTEX(mux_interval_mutex); |
10732 | ||
62b85639 SE |
10733 | static ssize_t |
10734 | perf_event_mux_interval_ms_store(struct device *dev, | |
10735 | struct device_attribute *attr, | |
10736 | const char *buf, size_t count) | |
10737 | { | |
10738 | struct pmu *pmu = dev_get_drvdata(dev); | |
10739 | int timer, cpu, ret; | |
10740 | ||
10741 | ret = kstrtoint(buf, 0, &timer); | |
10742 | if (ret) | |
10743 | return ret; | |
10744 | ||
10745 | if (timer < 1) | |
10746 | return -EINVAL; | |
10747 | ||
10748 | /* same value, noting to do */ | |
10749 | if (timer == pmu->hrtimer_interval_ms) | |
10750 | return count; | |
10751 | ||
272325c4 | 10752 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10753 | pmu->hrtimer_interval_ms = timer; |
10754 | ||
10755 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10756 | cpus_read_lock(); |
272325c4 | 10757 | for_each_online_cpu(cpu) { |
62b85639 SE |
10758 | struct perf_cpu_context *cpuctx; |
10759 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10760 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10761 | ||
272325c4 PZ |
10762 | cpu_function_call(cpu, |
10763 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10764 | } |
a63fbed7 | 10765 | cpus_read_unlock(); |
272325c4 | 10766 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10767 | |
10768 | return count; | |
10769 | } | |
90826ca7 | 10770 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10771 | |
90826ca7 GKH |
10772 | static struct attribute *pmu_dev_attrs[] = { |
10773 | &dev_attr_type.attr, | |
10774 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10775 | NULL, | |
abe43400 | 10776 | }; |
90826ca7 | 10777 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10778 | |
10779 | static int pmu_bus_running; | |
10780 | static struct bus_type pmu_bus = { | |
10781 | .name = "event_source", | |
90826ca7 | 10782 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10783 | }; |
10784 | ||
10785 | static void pmu_dev_release(struct device *dev) | |
10786 | { | |
10787 | kfree(dev); | |
10788 | } | |
10789 | ||
10790 | static int pmu_dev_alloc(struct pmu *pmu) | |
10791 | { | |
10792 | int ret = -ENOMEM; | |
10793 | ||
10794 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10795 | if (!pmu->dev) | |
10796 | goto out; | |
10797 | ||
0c9d42ed | 10798 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10799 | device_initialize(pmu->dev); |
10800 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10801 | if (ret) | |
10802 | goto free_dev; | |
10803 | ||
10804 | dev_set_drvdata(pmu->dev, pmu); | |
10805 | pmu->dev->bus = &pmu_bus; | |
10806 | pmu->dev->release = pmu_dev_release; | |
10807 | ret = device_add(pmu->dev); | |
10808 | if (ret) | |
10809 | goto free_dev; | |
10810 | ||
6e855cd4 AS |
10811 | /* For PMUs with address filters, throw in an extra attribute: */ |
10812 | if (pmu->nr_addr_filters) | |
10813 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10814 | ||
10815 | if (ret) | |
10816 | goto del_dev; | |
10817 | ||
f3a3a825 JO |
10818 | if (pmu->attr_update) |
10819 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10820 | ||
10821 | if (ret) | |
10822 | goto del_dev; | |
10823 | ||
abe43400 PZ |
10824 | out: |
10825 | return ret; | |
10826 | ||
6e855cd4 AS |
10827 | del_dev: |
10828 | device_del(pmu->dev); | |
10829 | ||
abe43400 PZ |
10830 | free_dev: |
10831 | put_device(pmu->dev); | |
10832 | goto out; | |
10833 | } | |
10834 | ||
547e9fd7 | 10835 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10836 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10837 | |
03d8e80b | 10838 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10839 | { |
66d258c5 | 10840 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10841 | |
b0a873eb | 10842 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10843 | ret = -ENOMEM; |
10844 | pmu->pmu_disable_count = alloc_percpu(int); | |
10845 | if (!pmu->pmu_disable_count) | |
10846 | goto unlock; | |
f29ac756 | 10847 | |
2e80a82a PZ |
10848 | pmu->type = -1; |
10849 | if (!name) | |
10850 | goto skip_type; | |
10851 | pmu->name = name; | |
10852 | ||
66d258c5 PZ |
10853 | if (type != PERF_TYPE_SOFTWARE) { |
10854 | if (type >= 0) | |
10855 | max = type; | |
10856 | ||
10857 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10858 | if (ret < 0) | |
2e80a82a | 10859 | goto free_pdc; |
66d258c5 PZ |
10860 | |
10861 | WARN_ON(type >= 0 && ret != type); | |
10862 | ||
10863 | type = ret; | |
2e80a82a PZ |
10864 | } |
10865 | pmu->type = type; | |
10866 | ||
abe43400 PZ |
10867 | if (pmu_bus_running) { |
10868 | ret = pmu_dev_alloc(pmu); | |
10869 | if (ret) | |
10870 | goto free_idr; | |
10871 | } | |
10872 | ||
2e80a82a | 10873 | skip_type: |
26657848 PZ |
10874 | if (pmu->task_ctx_nr == perf_hw_context) { |
10875 | static int hw_context_taken = 0; | |
10876 | ||
5101ef20 MR |
10877 | /* |
10878 | * Other than systems with heterogeneous CPUs, it never makes | |
10879 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10880 | * uncore must use perf_invalid_context. | |
10881 | */ | |
10882 | if (WARN_ON_ONCE(hw_context_taken && | |
10883 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10884 | pmu->task_ctx_nr = perf_invalid_context; |
10885 | ||
10886 | hw_context_taken = 1; | |
10887 | } | |
10888 | ||
8dc85d54 PZ |
10889 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10890 | if (pmu->pmu_cpu_context) | |
10891 | goto got_cpu_context; | |
f29ac756 | 10892 | |
c4814202 | 10893 | ret = -ENOMEM; |
108b02cf PZ |
10894 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10895 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10896 | goto free_dev; |
f344011c | 10897 | |
108b02cf PZ |
10898 | for_each_possible_cpu(cpu) { |
10899 | struct perf_cpu_context *cpuctx; | |
10900 | ||
10901 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10902 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10903 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10904 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10905 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10906 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10907 | |
272325c4 | 10908 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
10909 | |
10910 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
10911 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 10912 | } |
76e1d904 | 10913 | |
8dc85d54 | 10914 | got_cpu_context: |
ad5133b7 PZ |
10915 | if (!pmu->start_txn) { |
10916 | if (pmu->pmu_enable) { | |
10917 | /* | |
10918 | * If we have pmu_enable/pmu_disable calls, install | |
10919 | * transaction stubs that use that to try and batch | |
10920 | * hardware accesses. | |
10921 | */ | |
10922 | pmu->start_txn = perf_pmu_start_txn; | |
10923 | pmu->commit_txn = perf_pmu_commit_txn; | |
10924 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10925 | } else { | |
fbbe0701 | 10926 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10927 | pmu->commit_txn = perf_pmu_nop_int; |
10928 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10929 | } |
5c92d124 | 10930 | } |
15dbf27c | 10931 | |
ad5133b7 PZ |
10932 | if (!pmu->pmu_enable) { |
10933 | pmu->pmu_enable = perf_pmu_nop_void; | |
10934 | pmu->pmu_disable = perf_pmu_nop_void; | |
10935 | } | |
10936 | ||
81ec3f3c JO |
10937 | if (!pmu->check_period) |
10938 | pmu->check_period = perf_event_nop_int; | |
10939 | ||
35edc2a5 PZ |
10940 | if (!pmu->event_idx) |
10941 | pmu->event_idx = perf_event_idx_default; | |
10942 | ||
d44f821b LK |
10943 | /* |
10944 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10945 | * since these cannot be in the IDR. This way the linear search | |
10946 | * is fast, provided a valid software event is provided. | |
10947 | */ | |
10948 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10949 | list_add_rcu(&pmu->entry, &pmus); | |
10950 | else | |
10951 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10952 | ||
bed5b25a | 10953 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10954 | ret = 0; |
10955 | unlock: | |
b0a873eb PZ |
10956 | mutex_unlock(&pmus_lock); |
10957 | ||
33696fc0 | 10958 | return ret; |
108b02cf | 10959 | |
abe43400 PZ |
10960 | free_dev: |
10961 | device_del(pmu->dev); | |
10962 | put_device(pmu->dev); | |
10963 | ||
2e80a82a | 10964 | free_idr: |
66d258c5 | 10965 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10966 | idr_remove(&pmu_idr, pmu->type); |
10967 | ||
108b02cf PZ |
10968 | free_pdc: |
10969 | free_percpu(pmu->pmu_disable_count); | |
10970 | goto unlock; | |
f29ac756 | 10971 | } |
c464c76e | 10972 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10973 | |
b0a873eb | 10974 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10975 | { |
b0a873eb PZ |
10976 | mutex_lock(&pmus_lock); |
10977 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10978 | |
0475f9ea | 10979 | /* |
cde8e884 PZ |
10980 | * We dereference the pmu list under both SRCU and regular RCU, so |
10981 | * synchronize against both of those. | |
0475f9ea | 10982 | */ |
b0a873eb | 10983 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10984 | synchronize_rcu(); |
d6d020e9 | 10985 | |
33696fc0 | 10986 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10987 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10988 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10989 | if (pmu_bus_running) { |
0933840a JO |
10990 | if (pmu->nr_addr_filters) |
10991 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10992 | device_del(pmu->dev); | |
10993 | put_device(pmu->dev); | |
10994 | } | |
51676957 | 10995 | free_pmu_context(pmu); |
a9f97721 | 10996 | mutex_unlock(&pmus_lock); |
b0a873eb | 10997 | } |
c464c76e | 10998 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10999 | |
e321d02d KL |
11000 | static inline bool has_extended_regs(struct perf_event *event) |
11001 | { | |
11002 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
11003 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
11004 | } | |
11005 | ||
cc34b98b MR |
11006 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
11007 | { | |
ccd41c86 | 11008 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
11009 | int ret; |
11010 | ||
11011 | if (!try_module_get(pmu->module)) | |
11012 | return -ENODEV; | |
ccd41c86 | 11013 | |
0c7296ca PZ |
11014 | /* |
11015 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
11016 | * for example, validate if the group fits on the PMU. Therefore, | |
11017 | * if this is a sibling event, acquire the ctx->mutex to protect | |
11018 | * the sibling_list. | |
11019 | */ | |
11020 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
11021 | /* |
11022 | * This ctx->mutex can nest when we're called through | |
11023 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
11024 | */ | |
11025 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
11026 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
11027 | BUG_ON(!ctx); |
11028 | } | |
11029 | ||
cc34b98b MR |
11030 | event->pmu = pmu; |
11031 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
11032 | |
11033 | if (ctx) | |
11034 | perf_event_ctx_unlock(event->group_leader, ctx); | |
11035 | ||
cc6795ae | 11036 | if (!ret) { |
e321d02d KL |
11037 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
11038 | has_extended_regs(event)) | |
11039 | ret = -EOPNOTSUPP; | |
11040 | ||
cc6795ae | 11041 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 11042 | event_has_any_exclude_flag(event)) |
cc6795ae | 11043 | ret = -EINVAL; |
e321d02d KL |
11044 | |
11045 | if (ret && event->destroy) | |
11046 | event->destroy(event); | |
cc6795ae AM |
11047 | } |
11048 | ||
cc34b98b MR |
11049 | if (ret) |
11050 | module_put(pmu->module); | |
11051 | ||
11052 | return ret; | |
11053 | } | |
11054 | ||
18ab2cd3 | 11055 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 11056 | { |
66d258c5 | 11057 | int idx, type, ret; |
85c617ab | 11058 | struct pmu *pmu; |
b0a873eb PZ |
11059 | |
11060 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 11061 | |
40999312 KL |
11062 | /* Try parent's PMU first: */ |
11063 | if (event->parent && event->parent->pmu) { | |
11064 | pmu = event->parent->pmu; | |
11065 | ret = perf_try_init_event(pmu, event); | |
11066 | if (!ret) | |
11067 | goto unlock; | |
11068 | } | |
11069 | ||
66d258c5 PZ |
11070 | /* |
11071 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
11072 | * are often aliases for PERF_TYPE_RAW. | |
11073 | */ | |
11074 | type = event->attr.type; | |
11075 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
11076 | type = PERF_TYPE_RAW; | |
11077 | ||
11078 | again: | |
2e80a82a | 11079 | rcu_read_lock(); |
66d258c5 | 11080 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 11081 | rcu_read_unlock(); |
940c5b29 | 11082 | if (pmu) { |
cc34b98b | 11083 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
11084 | if (ret == -ENOENT && event->attr.type != type) { |
11085 | type = event->attr.type; | |
11086 | goto again; | |
11087 | } | |
11088 | ||
940c5b29 LM |
11089 | if (ret) |
11090 | pmu = ERR_PTR(ret); | |
66d258c5 | 11091 | |
2e80a82a | 11092 | goto unlock; |
940c5b29 | 11093 | } |
2e80a82a | 11094 | |
9f0bff11 | 11095 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 11096 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 11097 | if (!ret) |
e5f4d339 | 11098 | goto unlock; |
76e1d904 | 11099 | |
b0a873eb PZ |
11100 | if (ret != -ENOENT) { |
11101 | pmu = ERR_PTR(ret); | |
e5f4d339 | 11102 | goto unlock; |
f344011c | 11103 | } |
5c92d124 | 11104 | } |
e5f4d339 PZ |
11105 | pmu = ERR_PTR(-ENOENT); |
11106 | unlock: | |
b0a873eb | 11107 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 11108 | |
4aeb0b42 | 11109 | return pmu; |
5c92d124 IM |
11110 | } |
11111 | ||
f2fb6bef KL |
11112 | static void attach_sb_event(struct perf_event *event) |
11113 | { | |
11114 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
11115 | ||
11116 | raw_spin_lock(&pel->lock); | |
11117 | list_add_rcu(&event->sb_list, &pel->list); | |
11118 | raw_spin_unlock(&pel->lock); | |
11119 | } | |
11120 | ||
aab5b71e PZ |
11121 | /* |
11122 | * We keep a list of all !task (and therefore per-cpu) events | |
11123 | * that need to receive side-band records. | |
11124 | * | |
11125 | * This avoids having to scan all the various PMU per-cpu contexts | |
11126 | * looking for them. | |
11127 | */ | |
f2fb6bef KL |
11128 | static void account_pmu_sb_event(struct perf_event *event) |
11129 | { | |
a4f144eb | 11130 | if (is_sb_event(event)) |
f2fb6bef KL |
11131 | attach_sb_event(event); |
11132 | } | |
11133 | ||
4beb31f3 FW |
11134 | static void account_event_cpu(struct perf_event *event, int cpu) |
11135 | { | |
11136 | if (event->parent) | |
11137 | return; | |
11138 | ||
4beb31f3 FW |
11139 | if (is_cgroup_event(event)) |
11140 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
11141 | } | |
11142 | ||
555e0c1e FW |
11143 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
11144 | static void account_freq_event_nohz(void) | |
11145 | { | |
11146 | #ifdef CONFIG_NO_HZ_FULL | |
11147 | /* Lock so we don't race with concurrent unaccount */ | |
11148 | spin_lock(&nr_freq_lock); | |
11149 | if (atomic_inc_return(&nr_freq_events) == 1) | |
11150 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
11151 | spin_unlock(&nr_freq_lock); | |
11152 | #endif | |
11153 | } | |
11154 | ||
11155 | static void account_freq_event(void) | |
11156 | { | |
11157 | if (tick_nohz_full_enabled()) | |
11158 | account_freq_event_nohz(); | |
11159 | else | |
11160 | atomic_inc(&nr_freq_events); | |
11161 | } | |
11162 | ||
11163 | ||
766d6c07 FW |
11164 | static void account_event(struct perf_event *event) |
11165 | { | |
25432ae9 PZ |
11166 | bool inc = false; |
11167 | ||
4beb31f3 FW |
11168 | if (event->parent) |
11169 | return; | |
11170 | ||
766d6c07 | 11171 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 11172 | inc = true; |
766d6c07 FW |
11173 | if (event->attr.mmap || event->attr.mmap_data) |
11174 | atomic_inc(&nr_mmap_events); | |
11175 | if (event->attr.comm) | |
11176 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
11177 | if (event->attr.namespaces) |
11178 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
11179 | if (event->attr.cgroup) |
11180 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
11181 | if (event->attr.task) |
11182 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
11183 | if (event->attr.freq) |
11184 | account_freq_event(); | |
45ac1403 AH |
11185 | if (event->attr.context_switch) { |
11186 | atomic_inc(&nr_switch_events); | |
25432ae9 | 11187 | inc = true; |
45ac1403 | 11188 | } |
4beb31f3 | 11189 | if (has_branch_stack(event)) |
25432ae9 | 11190 | inc = true; |
4beb31f3 | 11191 | if (is_cgroup_event(event)) |
25432ae9 | 11192 | inc = true; |
76193a94 SL |
11193 | if (event->attr.ksymbol) |
11194 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
11195 | if (event->attr.bpf_event) |
11196 | atomic_inc(&nr_bpf_events); | |
e17d43b9 AH |
11197 | if (event->attr.text_poke) |
11198 | atomic_inc(&nr_text_poke_events); | |
25432ae9 | 11199 | |
9107c89e | 11200 | if (inc) { |
5bce9db1 AS |
11201 | /* |
11202 | * We need the mutex here because static_branch_enable() | |
11203 | * must complete *before* the perf_sched_count increment | |
11204 | * becomes visible. | |
11205 | */ | |
9107c89e PZ |
11206 | if (atomic_inc_not_zero(&perf_sched_count)) |
11207 | goto enabled; | |
11208 | ||
11209 | mutex_lock(&perf_sched_mutex); | |
11210 | if (!atomic_read(&perf_sched_count)) { | |
11211 | static_branch_enable(&perf_sched_events); | |
11212 | /* | |
11213 | * Guarantee that all CPUs observe they key change and | |
11214 | * call the perf scheduling hooks before proceeding to | |
11215 | * install events that need them. | |
11216 | */ | |
0809d954 | 11217 | synchronize_rcu(); |
9107c89e PZ |
11218 | } |
11219 | /* | |
11220 | * Now that we have waited for the sync_sched(), allow further | |
11221 | * increments to by-pass the mutex. | |
11222 | */ | |
11223 | atomic_inc(&perf_sched_count); | |
11224 | mutex_unlock(&perf_sched_mutex); | |
11225 | } | |
11226 | enabled: | |
4beb31f3 FW |
11227 | |
11228 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
11229 | |
11230 | account_pmu_sb_event(event); | |
766d6c07 FW |
11231 | } |
11232 | ||
0793a61d | 11233 | /* |
788faab7 | 11234 | * Allocate and initialize an event structure |
0793a61d | 11235 | */ |
cdd6c482 | 11236 | static struct perf_event * |
c3f00c70 | 11237 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
11238 | struct task_struct *task, |
11239 | struct perf_event *group_leader, | |
11240 | struct perf_event *parent_event, | |
4dc0da86 | 11241 | perf_overflow_handler_t overflow_handler, |
79dff51e | 11242 | void *context, int cgroup_fd) |
0793a61d | 11243 | { |
51b0fe39 | 11244 | struct pmu *pmu; |
cdd6c482 IM |
11245 | struct perf_event *event; |
11246 | struct hw_perf_event *hwc; | |
90983b16 | 11247 | long err = -EINVAL; |
0793a61d | 11248 | |
66832eb4 ON |
11249 | if ((unsigned)cpu >= nr_cpu_ids) { |
11250 | if (!task || cpu != -1) | |
11251 | return ERR_PTR(-EINVAL); | |
11252 | } | |
11253 | ||
c3f00c70 | 11254 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 11255 | if (!event) |
d5d2bc0d | 11256 | return ERR_PTR(-ENOMEM); |
0793a61d | 11257 | |
04289bb9 | 11258 | /* |
cdd6c482 | 11259 | * Single events are their own group leaders, with an |
04289bb9 IM |
11260 | * empty sibling list: |
11261 | */ | |
11262 | if (!group_leader) | |
cdd6c482 | 11263 | group_leader = event; |
04289bb9 | 11264 | |
cdd6c482 IM |
11265 | mutex_init(&event->child_mutex); |
11266 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 11267 | |
cdd6c482 IM |
11268 | INIT_LIST_HEAD(&event->event_entry); |
11269 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 11270 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 11271 | init_event_group(event); |
10c6db11 | 11272 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 11273 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 11274 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
11275 | INIT_HLIST_NODE(&event->hlist_entry); |
11276 | ||
10c6db11 | 11277 | |
cdd6c482 | 11278 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 11279 | event->pending_disable = -1; |
e360adbe | 11280 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 11281 | |
cdd6c482 | 11282 | mutex_init(&event->mmap_mutex); |
375637bc | 11283 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11284 | |
a6fa941d | 11285 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11286 | event->cpu = cpu; |
11287 | event->attr = *attr; | |
11288 | event->group_leader = group_leader; | |
11289 | event->pmu = NULL; | |
cdd6c482 | 11290 | event->oncpu = -1; |
a96bbc16 | 11291 | |
cdd6c482 | 11292 | event->parent = parent_event; |
b84fbc9f | 11293 | |
17cf22c3 | 11294 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11295 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11296 | |
cdd6c482 | 11297 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11298 | |
d580ff86 PZ |
11299 | if (task) { |
11300 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11301 | /* |
50f16a8b PZ |
11302 | * XXX pmu::event_init needs to know what task to account to |
11303 | * and we cannot use the ctx information because we need the | |
11304 | * pmu before we get a ctx. | |
d580ff86 | 11305 | */ |
7b3c92b8 | 11306 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11307 | } |
11308 | ||
34f43927 PZ |
11309 | event->clock = &local_clock; |
11310 | if (parent_event) | |
11311 | event->clock = parent_event->clock; | |
11312 | ||
4dc0da86 | 11313 | if (!overflow_handler && parent_event) { |
b326e956 | 11314 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11315 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11316 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11317 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11318 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11319 | |
85192dbf | 11320 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11321 | event->prog = prog; |
11322 | event->orig_overflow_handler = | |
11323 | parent_event->orig_overflow_handler; | |
11324 | } | |
11325 | #endif | |
4dc0da86 | 11326 | } |
66832eb4 | 11327 | |
1879445d WN |
11328 | if (overflow_handler) { |
11329 | event->overflow_handler = overflow_handler; | |
11330 | event->overflow_handler_context = context; | |
9ecda41a WN |
11331 | } else if (is_write_backward(event)){ |
11332 | event->overflow_handler = perf_event_output_backward; | |
11333 | event->overflow_handler_context = NULL; | |
1879445d | 11334 | } else { |
9ecda41a | 11335 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11336 | event->overflow_handler_context = NULL; |
11337 | } | |
97eaf530 | 11338 | |
0231bb53 | 11339 | perf_event__state_init(event); |
a86ed508 | 11340 | |
4aeb0b42 | 11341 | pmu = NULL; |
b8e83514 | 11342 | |
cdd6c482 | 11343 | hwc = &event->hw; |
bd2b5b12 | 11344 | hwc->sample_period = attr->sample_period; |
0d48696f | 11345 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11346 | hwc->sample_period = 1; |
eced1dfc | 11347 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11348 | |
e7850595 | 11349 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11350 | |
2023b359 | 11351 | /* |
ba5213ae PZ |
11352 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11353 | * See perf_output_read(). | |
2023b359 | 11354 | */ |
ba5213ae | 11355 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11356 | goto err_ns; |
a46a2300 YZ |
11357 | |
11358 | if (!has_branch_stack(event)) | |
11359 | event->attr.branch_sample_type = 0; | |
2023b359 | 11360 | |
b0a873eb | 11361 | pmu = perf_init_event(event); |
85c617ab | 11362 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11363 | err = PTR_ERR(pmu); |
90983b16 | 11364 | goto err_ns; |
621a01ea | 11365 | } |
d5d2bc0d | 11366 | |
09f4e8f0 PZ |
11367 | /* |
11368 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11369 | * be different on other CPUs in the uncore mask. | |
11370 | */ | |
11371 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11372 | err = -EINVAL; | |
11373 | goto err_pmu; | |
11374 | } | |
11375 | ||
ab43762e AS |
11376 | if (event->attr.aux_output && |
11377 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11378 | err = -EOPNOTSUPP; | |
11379 | goto err_pmu; | |
11380 | } | |
11381 | ||
98add2af PZ |
11382 | if (cgroup_fd != -1) { |
11383 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11384 | if (err) | |
11385 | goto err_pmu; | |
11386 | } | |
11387 | ||
bed5b25a AS |
11388 | err = exclusive_event_init(event); |
11389 | if (err) | |
11390 | goto err_pmu; | |
11391 | ||
375637bc | 11392 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11393 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11394 | sizeof(struct perf_addr_filter_range), | |
11395 | GFP_KERNEL); | |
11396 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11397 | err = -ENOMEM; |
375637bc | 11398 | goto err_per_task; |
36cc2b92 | 11399 | } |
375637bc | 11400 | |
18736eef AS |
11401 | /* |
11402 | * Clone the parent's vma offsets: they are valid until exec() | |
11403 | * even if the mm is not shared with the parent. | |
11404 | */ | |
11405 | if (event->parent) { | |
11406 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11407 | ||
11408 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11409 | memcpy(event->addr_filter_ranges, |
11410 | event->parent->addr_filter_ranges, | |
11411 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11412 | raw_spin_unlock_irq(&ifh->lock); |
11413 | } | |
11414 | ||
375637bc AS |
11415 | /* force hw sync on the address filters */ |
11416 | event->addr_filters_gen = 1; | |
11417 | } | |
11418 | ||
cdd6c482 | 11419 | if (!event->parent) { |
927c7a9e | 11420 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11421 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11422 | if (err) |
375637bc | 11423 | goto err_addr_filters; |
d010b332 | 11424 | } |
f344011c | 11425 | } |
9ee318a7 | 11426 | |
da97e184 JFG |
11427 | err = security_perf_event_alloc(event); |
11428 | if (err) | |
11429 | goto err_callchain_buffer; | |
11430 | ||
927a5570 AS |
11431 | /* symmetric to unaccount_event() in _free_event() */ |
11432 | account_event(event); | |
11433 | ||
cdd6c482 | 11434 | return event; |
90983b16 | 11435 | |
da97e184 JFG |
11436 | err_callchain_buffer: |
11437 | if (!event->parent) { | |
11438 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11439 | put_callchain_buffers(); | |
11440 | } | |
375637bc | 11441 | err_addr_filters: |
c60f83b8 | 11442 | kfree(event->addr_filter_ranges); |
375637bc | 11443 | |
bed5b25a AS |
11444 | err_per_task: |
11445 | exclusive_event_destroy(event); | |
11446 | ||
90983b16 | 11447 | err_pmu: |
98add2af PZ |
11448 | if (is_cgroup_event(event)) |
11449 | perf_detach_cgroup(event); | |
90983b16 FW |
11450 | if (event->destroy) |
11451 | event->destroy(event); | |
c464c76e | 11452 | module_put(pmu->module); |
90983b16 FW |
11453 | err_ns: |
11454 | if (event->ns) | |
11455 | put_pid_ns(event->ns); | |
621b6d2e PB |
11456 | if (event->hw.target) |
11457 | put_task_struct(event->hw.target); | |
90983b16 FW |
11458 | kfree(event); |
11459 | ||
11460 | return ERR_PTR(err); | |
0793a61d TG |
11461 | } |
11462 | ||
cdd6c482 IM |
11463 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11464 | struct perf_event_attr *attr) | |
974802ea | 11465 | { |
974802ea | 11466 | u32 size; |
cdf8073d | 11467 | int ret; |
974802ea | 11468 | |
c2ba8f41 | 11469 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11470 | memset(attr, 0, sizeof(*attr)); |
11471 | ||
11472 | ret = get_user(size, &uattr->size); | |
11473 | if (ret) | |
11474 | return ret; | |
11475 | ||
c2ba8f41 AS |
11476 | /* ABI compatibility quirk: */ |
11477 | if (!size) | |
974802ea | 11478 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11479 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11480 | goto err_size; |
11481 | ||
c2ba8f41 AS |
11482 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11483 | if (ret) { | |
11484 | if (ret == -E2BIG) | |
11485 | goto err_size; | |
11486 | return ret; | |
974802ea PZ |
11487 | } |
11488 | ||
f12f42ac MX |
11489 | attr->size = size; |
11490 | ||
a4faf00d | 11491 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11492 | return -EINVAL; |
11493 | ||
11494 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11495 | return -EINVAL; | |
11496 | ||
11497 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11498 | return -EINVAL; | |
11499 | ||
bce38cd5 SE |
11500 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11501 | u64 mask = attr->branch_sample_type; | |
11502 | ||
11503 | /* only using defined bits */ | |
11504 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11505 | return -EINVAL; | |
11506 | ||
11507 | /* at least one branch bit must be set */ | |
11508 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11509 | return -EINVAL; | |
11510 | ||
bce38cd5 SE |
11511 | /* propagate priv level, when not set for branch */ |
11512 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11513 | ||
11514 | /* exclude_kernel checked on syscall entry */ | |
11515 | if (!attr->exclude_kernel) | |
11516 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11517 | ||
11518 | if (!attr->exclude_user) | |
11519 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11520 | ||
11521 | if (!attr->exclude_hv) | |
11522 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11523 | /* | |
11524 | * adjust user setting (for HW filter setup) | |
11525 | */ | |
11526 | attr->branch_sample_type = mask; | |
11527 | } | |
e712209a | 11528 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11529 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11530 | ret = perf_allow_kernel(attr); | |
11531 | if (ret) | |
11532 | return ret; | |
11533 | } | |
bce38cd5 | 11534 | } |
4018994f | 11535 | |
c5ebcedb | 11536 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11537 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11538 | if (ret) |
11539 | return ret; | |
11540 | } | |
11541 | ||
11542 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11543 | if (!arch_perf_have_user_stack_dump()) | |
11544 | return -ENOSYS; | |
11545 | ||
11546 | /* | |
11547 | * We have __u32 type for the size, but so far | |
11548 | * we can only use __u16 as maximum due to the | |
11549 | * __u16 sample size limit. | |
11550 | */ | |
11551 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11552 | return -EINVAL; |
c5ebcedb | 11553 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11554 | return -EINVAL; |
c5ebcedb | 11555 | } |
4018994f | 11556 | |
5f970521 JO |
11557 | if (!attr->sample_max_stack) |
11558 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11559 | ||
60e2364e SE |
11560 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11561 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11562 | |
11563 | #ifndef CONFIG_CGROUP_PERF | |
11564 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11565 | return -EINVAL; | |
11566 | #endif | |
11567 | ||
974802ea PZ |
11568 | out: |
11569 | return ret; | |
11570 | ||
11571 | err_size: | |
11572 | put_user(sizeof(*attr), &uattr->size); | |
11573 | ret = -E2BIG; | |
11574 | goto out; | |
11575 | } | |
11576 | ||
ac9721f3 PZ |
11577 | static int |
11578 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11579 | { |
56de4e8f | 11580 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11581 | int ret = -EINVAL; |
11582 | ||
ac9721f3 | 11583 | if (!output_event) |
a4be7c27 PZ |
11584 | goto set; |
11585 | ||
ac9721f3 PZ |
11586 | /* don't allow circular references */ |
11587 | if (event == output_event) | |
a4be7c27 PZ |
11588 | goto out; |
11589 | ||
0f139300 PZ |
11590 | /* |
11591 | * Don't allow cross-cpu buffers | |
11592 | */ | |
11593 | if (output_event->cpu != event->cpu) | |
11594 | goto out; | |
11595 | ||
11596 | /* | |
76369139 | 11597 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11598 | */ |
11599 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11600 | goto out; | |
11601 | ||
34f43927 PZ |
11602 | /* |
11603 | * Mixing clocks in the same buffer is trouble you don't need. | |
11604 | */ | |
11605 | if (output_event->clock != event->clock) | |
11606 | goto out; | |
11607 | ||
9ecda41a WN |
11608 | /* |
11609 | * Either writing ring buffer from beginning or from end. | |
11610 | * Mixing is not allowed. | |
11611 | */ | |
11612 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11613 | goto out; | |
11614 | ||
45bfb2e5 PZ |
11615 | /* |
11616 | * If both events generate aux data, they must be on the same PMU | |
11617 | */ | |
11618 | if (has_aux(event) && has_aux(output_event) && | |
11619 | event->pmu != output_event->pmu) | |
11620 | goto out; | |
11621 | ||
a4be7c27 | 11622 | set: |
cdd6c482 | 11623 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11624 | /* Can't redirect output if we've got an active mmap() */ |
11625 | if (atomic_read(&event->mmap_count)) | |
11626 | goto unlock; | |
a4be7c27 | 11627 | |
ac9721f3 | 11628 | if (output_event) { |
76369139 FW |
11629 | /* get the rb we want to redirect to */ |
11630 | rb = ring_buffer_get(output_event); | |
11631 | if (!rb) | |
ac9721f3 | 11632 | goto unlock; |
a4be7c27 PZ |
11633 | } |
11634 | ||
b69cf536 | 11635 | ring_buffer_attach(event, rb); |
9bb5d40c | 11636 | |
a4be7c27 | 11637 | ret = 0; |
ac9721f3 PZ |
11638 | unlock: |
11639 | mutex_unlock(&event->mmap_mutex); | |
11640 | ||
a4be7c27 | 11641 | out: |
a4be7c27 PZ |
11642 | return ret; |
11643 | } | |
11644 | ||
f63a8daa PZ |
11645 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11646 | { | |
11647 | if (b < a) | |
11648 | swap(a, b); | |
11649 | ||
11650 | mutex_lock(a); | |
11651 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11652 | } | |
11653 | ||
34f43927 PZ |
11654 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11655 | { | |
11656 | bool nmi_safe = false; | |
11657 | ||
11658 | switch (clk_id) { | |
11659 | case CLOCK_MONOTONIC: | |
11660 | event->clock = &ktime_get_mono_fast_ns; | |
11661 | nmi_safe = true; | |
11662 | break; | |
11663 | ||
11664 | case CLOCK_MONOTONIC_RAW: | |
11665 | event->clock = &ktime_get_raw_fast_ns; | |
11666 | nmi_safe = true; | |
11667 | break; | |
11668 | ||
11669 | case CLOCK_REALTIME: | |
11670 | event->clock = &ktime_get_real_ns; | |
11671 | break; | |
11672 | ||
11673 | case CLOCK_BOOTTIME: | |
9285ec4c | 11674 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11675 | break; |
11676 | ||
11677 | case CLOCK_TAI: | |
9285ec4c | 11678 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11679 | break; |
11680 | ||
11681 | default: | |
11682 | return -EINVAL; | |
11683 | } | |
11684 | ||
11685 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11686 | return -EINVAL; | |
11687 | ||
11688 | return 0; | |
11689 | } | |
11690 | ||
321027c1 PZ |
11691 | /* |
11692 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11693 | * mutexes. | |
11694 | */ | |
11695 | static struct perf_event_context * | |
11696 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11697 | struct perf_event_context *ctx) | |
11698 | { | |
11699 | struct perf_event_context *gctx; | |
11700 | ||
11701 | again: | |
11702 | rcu_read_lock(); | |
11703 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11704 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11705 | rcu_read_unlock(); |
11706 | goto again; | |
11707 | } | |
11708 | rcu_read_unlock(); | |
11709 | ||
11710 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11711 | ||
11712 | if (group_leader->ctx != gctx) { | |
11713 | mutex_unlock(&ctx->mutex); | |
11714 | mutex_unlock(&gctx->mutex); | |
11715 | put_ctx(gctx); | |
11716 | goto again; | |
11717 | } | |
11718 | ||
11719 | return gctx; | |
11720 | } | |
11721 | ||
0793a61d | 11722 | /** |
cdd6c482 | 11723 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11724 | * |
cdd6c482 | 11725 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11726 | * @pid: target pid |
9f66a381 | 11727 | * @cpu: target cpu |
cdd6c482 | 11728 | * @group_fd: group leader event fd |
0793a61d | 11729 | */ |
cdd6c482 IM |
11730 | SYSCALL_DEFINE5(perf_event_open, |
11731 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11732 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11733 | { |
b04243ef PZ |
11734 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11735 | struct perf_event *event, *sibling; | |
cdd6c482 | 11736 | struct perf_event_attr attr; |
3f649ab7 | 11737 | struct perf_event_context *ctx, *gctx; |
cdd6c482 | 11738 | struct file *event_file = NULL; |
2903ff01 | 11739 | struct fd group = {NULL, 0}; |
38a81da2 | 11740 | struct task_struct *task = NULL; |
89a1e187 | 11741 | struct pmu *pmu; |
ea635c64 | 11742 | int event_fd; |
b04243ef | 11743 | int move_group = 0; |
dc86cabe | 11744 | int err; |
a21b0b35 | 11745 | int f_flags = O_RDWR; |
79dff51e | 11746 | int cgroup_fd = -1; |
0793a61d | 11747 | |
2743a5b0 | 11748 | /* for future expandability... */ |
e5d1367f | 11749 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11750 | return -EINVAL; |
11751 | ||
da97e184 JFG |
11752 | /* Do we allow access to perf_event_open(2) ? */ |
11753 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11754 | if (err) | |
11755 | return err; | |
11756 | ||
dc86cabe IM |
11757 | err = perf_copy_attr(attr_uptr, &attr); |
11758 | if (err) | |
11759 | return err; | |
eab656ae | 11760 | |
0764771d | 11761 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11762 | err = perf_allow_kernel(&attr); |
11763 | if (err) | |
11764 | return err; | |
0764771d PZ |
11765 | } |
11766 | ||
e4222673 | 11767 | if (attr.namespaces) { |
18aa1856 | 11768 | if (!perfmon_capable()) |
e4222673 HB |
11769 | return -EACCES; |
11770 | } | |
11771 | ||
df58ab24 | 11772 | if (attr.freq) { |
cdd6c482 | 11773 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11774 | return -EINVAL; |
0819b2e3 PZ |
11775 | } else { |
11776 | if (attr.sample_period & (1ULL << 63)) | |
11777 | return -EINVAL; | |
df58ab24 PZ |
11778 | } |
11779 | ||
fc7ce9c7 | 11780 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11781 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11782 | err = perf_allow_kernel(&attr); | |
11783 | if (err) | |
11784 | return err; | |
11785 | } | |
fc7ce9c7 | 11786 | |
b0c8fdc7 DH |
11787 | err = security_locked_down(LOCKDOWN_PERF); |
11788 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11789 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11790 | return err; | |
11791 | ||
11792 | err = 0; | |
11793 | ||
e5d1367f SE |
11794 | /* |
11795 | * In cgroup mode, the pid argument is used to pass the fd | |
11796 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11797 | * designates the cpu on which to monitor threads from that | |
11798 | * cgroup. | |
11799 | */ | |
11800 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11801 | return -EINVAL; | |
11802 | ||
a21b0b35 YD |
11803 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11804 | f_flags |= O_CLOEXEC; | |
11805 | ||
11806 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11807 | if (event_fd < 0) |
11808 | return event_fd; | |
11809 | ||
ac9721f3 | 11810 | if (group_fd != -1) { |
2903ff01 AV |
11811 | err = perf_fget_light(group_fd, &group); |
11812 | if (err) | |
d14b12d7 | 11813 | goto err_fd; |
2903ff01 | 11814 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11815 | if (flags & PERF_FLAG_FD_OUTPUT) |
11816 | output_event = group_leader; | |
11817 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11818 | group_leader = NULL; | |
11819 | } | |
11820 | ||
e5d1367f | 11821 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11822 | task = find_lively_task_by_vpid(pid); |
11823 | if (IS_ERR(task)) { | |
11824 | err = PTR_ERR(task); | |
11825 | goto err_group_fd; | |
11826 | } | |
11827 | } | |
11828 | ||
1f4ee503 PZ |
11829 | if (task && group_leader && |
11830 | group_leader->attr.inherit != attr.inherit) { | |
11831 | err = -EINVAL; | |
11832 | goto err_task; | |
11833 | } | |
11834 | ||
79c9ce57 | 11835 | if (task) { |
69143038 | 11836 | err = mutex_lock_interruptible(&task->signal->exec_update_mutex); |
79c9ce57 | 11837 | if (err) |
e5aeee51 | 11838 | goto err_task; |
79c9ce57 PZ |
11839 | |
11840 | /* | |
45fd22da | 11841 | * Preserve ptrace permission check for backwards compatibility. |
79c9ce57 | 11842 | * |
69143038 | 11843 | * We must hold exec_update_mutex across this and any potential |
79c9ce57 PZ |
11844 | * perf_install_in_context() call for this new event to |
11845 | * serialize against exec() altering our credentials (and the | |
11846 | * perf_event_exit_task() that could imply). | |
11847 | */ | |
11848 | err = -EACCES; | |
45fd22da | 11849 | if (!perfmon_capable() && !ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) |
79c9ce57 PZ |
11850 | goto err_cred; |
11851 | } | |
11852 | ||
79dff51e MF |
11853 | if (flags & PERF_FLAG_PID_CGROUP) |
11854 | cgroup_fd = pid; | |
11855 | ||
4dc0da86 | 11856 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11857 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11858 | if (IS_ERR(event)) { |
11859 | err = PTR_ERR(event); | |
79c9ce57 | 11860 | goto err_cred; |
d14b12d7 SE |
11861 | } |
11862 | ||
53b25335 VW |
11863 | if (is_sampling_event(event)) { |
11864 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11865 | err = -EOPNOTSUPP; |
53b25335 VW |
11866 | goto err_alloc; |
11867 | } | |
11868 | } | |
11869 | ||
89a1e187 PZ |
11870 | /* |
11871 | * Special case software events and allow them to be part of | |
11872 | * any hardware group. | |
11873 | */ | |
11874 | pmu = event->pmu; | |
b04243ef | 11875 | |
34f43927 PZ |
11876 | if (attr.use_clockid) { |
11877 | err = perf_event_set_clock(event, attr.clockid); | |
11878 | if (err) | |
11879 | goto err_alloc; | |
11880 | } | |
11881 | ||
4ff6a8de DCC |
11882 | if (pmu->task_ctx_nr == perf_sw_context) |
11883 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11884 | ||
a1150c20 SL |
11885 | if (group_leader) { |
11886 | if (is_software_event(event) && | |
11887 | !in_software_context(group_leader)) { | |
b04243ef | 11888 | /* |
a1150c20 SL |
11889 | * If the event is a sw event, but the group_leader |
11890 | * is on hw context. | |
b04243ef | 11891 | * |
a1150c20 SL |
11892 | * Allow the addition of software events to hw |
11893 | * groups, this is safe because software events | |
11894 | * never fail to schedule. | |
b04243ef | 11895 | */ |
a1150c20 SL |
11896 | pmu = group_leader->ctx->pmu; |
11897 | } else if (!is_software_event(event) && | |
11898 | is_software_event(group_leader) && | |
4ff6a8de | 11899 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11900 | /* |
11901 | * In case the group is a pure software group, and we | |
11902 | * try to add a hardware event, move the whole group to | |
11903 | * the hardware context. | |
11904 | */ | |
11905 | move_group = 1; | |
11906 | } | |
11907 | } | |
89a1e187 PZ |
11908 | |
11909 | /* | |
11910 | * Get the target context (task or percpu): | |
11911 | */ | |
4af57ef2 | 11912 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11913 | if (IS_ERR(ctx)) { |
11914 | err = PTR_ERR(ctx); | |
c6be5a5c | 11915 | goto err_alloc; |
89a1e187 PZ |
11916 | } |
11917 | ||
ccff286d | 11918 | /* |
cdd6c482 | 11919 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11920 | */ |
ac9721f3 | 11921 | if (group_leader) { |
dc86cabe | 11922 | err = -EINVAL; |
04289bb9 | 11923 | |
04289bb9 | 11924 | /* |
ccff286d IM |
11925 | * Do not allow a recursive hierarchy (this new sibling |
11926 | * becoming part of another group-sibling): | |
11927 | */ | |
11928 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11929 | goto err_context; |
34f43927 PZ |
11930 | |
11931 | /* All events in a group should have the same clock */ | |
11932 | if (group_leader->clock != event->clock) | |
11933 | goto err_context; | |
11934 | ||
ccff286d | 11935 | /* |
64aee2a9 MR |
11936 | * Make sure we're both events for the same CPU; |
11937 | * grouping events for different CPUs is broken; since | |
11938 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11939 | */ |
64aee2a9 MR |
11940 | if (group_leader->cpu != event->cpu) |
11941 | goto err_context; | |
c3c87e77 | 11942 | |
64aee2a9 MR |
11943 | /* |
11944 | * Make sure we're both on the same task, or both | |
11945 | * per-CPU events. | |
11946 | */ | |
11947 | if (group_leader->ctx->task != ctx->task) | |
11948 | goto err_context; | |
11949 | ||
11950 | /* | |
11951 | * Do not allow to attach to a group in a different task | |
11952 | * or CPU context. If we're moving SW events, we'll fix | |
11953 | * this up later, so allow that. | |
11954 | */ | |
11955 | if (!move_group && group_leader->ctx != ctx) | |
11956 | goto err_context; | |
b04243ef | 11957 | |
3b6f9e5c PM |
11958 | /* |
11959 | * Only a group leader can be exclusive or pinned | |
11960 | */ | |
0d48696f | 11961 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11962 | goto err_context; |
ac9721f3 PZ |
11963 | } |
11964 | ||
11965 | if (output_event) { | |
11966 | err = perf_event_set_output(event, output_event); | |
11967 | if (err) | |
c3f00c70 | 11968 | goto err_context; |
ac9721f3 | 11969 | } |
0793a61d | 11970 | |
a21b0b35 YD |
11971 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11972 | f_flags); | |
ea635c64 AV |
11973 | if (IS_ERR(event_file)) { |
11974 | err = PTR_ERR(event_file); | |
201c2f85 | 11975 | event_file = NULL; |
c3f00c70 | 11976 | goto err_context; |
ea635c64 | 11977 | } |
9b51f66d | 11978 | |
b04243ef | 11979 | if (move_group) { |
321027c1 PZ |
11980 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11981 | ||
84c4e620 PZ |
11982 | if (gctx->task == TASK_TOMBSTONE) { |
11983 | err = -ESRCH; | |
11984 | goto err_locked; | |
11985 | } | |
321027c1 PZ |
11986 | |
11987 | /* | |
11988 | * Check if we raced against another sys_perf_event_open() call | |
11989 | * moving the software group underneath us. | |
11990 | */ | |
11991 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11992 | /* | |
11993 | * If someone moved the group out from under us, check | |
11994 | * if this new event wound up on the same ctx, if so | |
11995 | * its the regular !move_group case, otherwise fail. | |
11996 | */ | |
11997 | if (gctx != ctx) { | |
11998 | err = -EINVAL; | |
11999 | goto err_locked; | |
12000 | } else { | |
12001 | perf_event_ctx_unlock(group_leader, gctx); | |
12002 | move_group = 0; | |
12003 | } | |
12004 | } | |
8a58ddae AS |
12005 | |
12006 | /* | |
12007 | * Failure to create exclusive events returns -EBUSY. | |
12008 | */ | |
12009 | err = -EBUSY; | |
12010 | if (!exclusive_event_installable(group_leader, ctx)) | |
12011 | goto err_locked; | |
12012 | ||
12013 | for_each_sibling_event(sibling, group_leader) { | |
12014 | if (!exclusive_event_installable(sibling, ctx)) | |
12015 | goto err_locked; | |
12016 | } | |
f55fc2a5 PZ |
12017 | } else { |
12018 | mutex_lock(&ctx->mutex); | |
12019 | } | |
12020 | ||
84c4e620 PZ |
12021 | if (ctx->task == TASK_TOMBSTONE) { |
12022 | err = -ESRCH; | |
12023 | goto err_locked; | |
12024 | } | |
12025 | ||
a723968c PZ |
12026 | if (!perf_event_validate_size(event)) { |
12027 | err = -E2BIG; | |
12028 | goto err_locked; | |
12029 | } | |
12030 | ||
a63fbed7 TG |
12031 | if (!task) { |
12032 | /* | |
12033 | * Check if the @cpu we're creating an event for is online. | |
12034 | * | |
12035 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12036 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12037 | */ | |
12038 | struct perf_cpu_context *cpuctx = | |
12039 | container_of(ctx, struct perf_cpu_context, ctx); | |
12040 | ||
12041 | if (!cpuctx->online) { | |
12042 | err = -ENODEV; | |
12043 | goto err_locked; | |
12044 | } | |
12045 | } | |
12046 | ||
da9ec3d3 MR |
12047 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
12048 | err = -EINVAL; | |
ab43762e | 12049 | goto err_locked; |
da9ec3d3 | 12050 | } |
a63fbed7 | 12051 | |
f55fc2a5 PZ |
12052 | /* |
12053 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
12054 | * because we need to serialize with concurrent event creation. | |
12055 | */ | |
12056 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
12057 | err = -EBUSY; |
12058 | goto err_locked; | |
12059 | } | |
f63a8daa | 12060 | |
f55fc2a5 PZ |
12061 | WARN_ON_ONCE(ctx->parent_ctx); |
12062 | ||
79c9ce57 PZ |
12063 | /* |
12064 | * This is the point on no return; we cannot fail hereafter. This is | |
12065 | * where we start modifying current state. | |
12066 | */ | |
12067 | ||
f55fc2a5 | 12068 | if (move_group) { |
f63a8daa PZ |
12069 | /* |
12070 | * See perf_event_ctx_lock() for comments on the details | |
12071 | * of swizzling perf_event::ctx. | |
12072 | */ | |
45a0e07a | 12073 | perf_remove_from_context(group_leader, 0); |
279b5165 | 12074 | put_ctx(gctx); |
0231bb53 | 12075 | |
edb39592 | 12076 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 12077 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
12078 | put_ctx(gctx); |
12079 | } | |
b04243ef | 12080 | |
f63a8daa PZ |
12081 | /* |
12082 | * Wait for everybody to stop referencing the events through | |
12083 | * the old lists, before installing it on new lists. | |
12084 | */ | |
0cda4c02 | 12085 | synchronize_rcu(); |
f63a8daa | 12086 | |
8f95b435 PZI |
12087 | /* |
12088 | * Install the group siblings before the group leader. | |
12089 | * | |
12090 | * Because a group leader will try and install the entire group | |
12091 | * (through the sibling list, which is still in-tact), we can | |
12092 | * end up with siblings installed in the wrong context. | |
12093 | * | |
12094 | * By installing siblings first we NO-OP because they're not | |
12095 | * reachable through the group lists. | |
12096 | */ | |
edb39592 | 12097 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 12098 | perf_event__state_init(sibling); |
9fc81d87 | 12099 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
12100 | get_ctx(ctx); |
12101 | } | |
8f95b435 PZI |
12102 | |
12103 | /* | |
12104 | * Removing from the context ends up with disabled | |
12105 | * event. What we want here is event in the initial | |
12106 | * startup state, ready to be add into new context. | |
12107 | */ | |
12108 | perf_event__state_init(group_leader); | |
12109 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
12110 | get_ctx(ctx); | |
bed5b25a AS |
12111 | } |
12112 | ||
f73e22ab PZ |
12113 | /* |
12114 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
12115 | * that we're serialized against further additions and before | |
12116 | * perf_install_in_context() which is the point the event is active and | |
12117 | * can use these values. | |
12118 | */ | |
12119 | perf_event__header_size(event); | |
12120 | perf_event__id_header_size(event); | |
12121 | ||
78cd2c74 PZ |
12122 | event->owner = current; |
12123 | ||
e2d37cd2 | 12124 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12125 | perf_unpin_context(ctx); |
f63a8daa | 12126 | |
f55fc2a5 | 12127 | if (move_group) |
321027c1 | 12128 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 12129 | mutex_unlock(&ctx->mutex); |
9b51f66d | 12130 | |
79c9ce57 | 12131 | if (task) { |
69143038 | 12132 | mutex_unlock(&task->signal->exec_update_mutex); |
79c9ce57 PZ |
12133 | put_task_struct(task); |
12134 | } | |
12135 | ||
cdd6c482 IM |
12136 | mutex_lock(¤t->perf_event_mutex); |
12137 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
12138 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 12139 | |
8a49542c PZ |
12140 | /* |
12141 | * Drop the reference on the group_event after placing the | |
12142 | * new event on the sibling_list. This ensures destruction | |
12143 | * of the group leader will find the pointer to itself in | |
12144 | * perf_group_detach(). | |
12145 | */ | |
2903ff01 | 12146 | fdput(group); |
ea635c64 AV |
12147 | fd_install(event_fd, event_file); |
12148 | return event_fd; | |
0793a61d | 12149 | |
f55fc2a5 PZ |
12150 | err_locked: |
12151 | if (move_group) | |
321027c1 | 12152 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
12153 | mutex_unlock(&ctx->mutex); |
12154 | /* err_file: */ | |
12155 | fput(event_file); | |
c3f00c70 | 12156 | err_context: |
fe4b04fa | 12157 | perf_unpin_context(ctx); |
ea635c64 | 12158 | put_ctx(ctx); |
c6be5a5c | 12159 | err_alloc: |
13005627 PZ |
12160 | /* |
12161 | * If event_file is set, the fput() above will have called ->release() | |
12162 | * and that will take care of freeing the event. | |
12163 | */ | |
12164 | if (!event_file) | |
12165 | free_event(event); | |
79c9ce57 PZ |
12166 | err_cred: |
12167 | if (task) | |
69143038 | 12168 | mutex_unlock(&task->signal->exec_update_mutex); |
1f4ee503 | 12169 | err_task: |
e7d0bc04 PZ |
12170 | if (task) |
12171 | put_task_struct(task); | |
89a1e187 | 12172 | err_group_fd: |
2903ff01 | 12173 | fdput(group); |
ea635c64 AV |
12174 | err_fd: |
12175 | put_unused_fd(event_fd); | |
dc86cabe | 12176 | return err; |
0793a61d TG |
12177 | } |
12178 | ||
fb0459d7 AV |
12179 | /** |
12180 | * perf_event_create_kernel_counter | |
12181 | * | |
12182 | * @attr: attributes of the counter to create | |
12183 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 12184 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
12185 | */ |
12186 | struct perf_event * | |
12187 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 12188 | struct task_struct *task, |
4dc0da86 AK |
12189 | perf_overflow_handler_t overflow_handler, |
12190 | void *context) | |
fb0459d7 | 12191 | { |
fb0459d7 | 12192 | struct perf_event_context *ctx; |
c3f00c70 | 12193 | struct perf_event *event; |
fb0459d7 | 12194 | int err; |
d859e29f | 12195 | |
dce5affb AS |
12196 | /* |
12197 | * Grouping is not supported for kernel events, neither is 'AUX', | |
12198 | * make sure the caller's intentions are adjusted. | |
12199 | */ | |
12200 | if (attr->aux_output) | |
12201 | return ERR_PTR(-EINVAL); | |
12202 | ||
4dc0da86 | 12203 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 12204 | overflow_handler, context, -1); |
c3f00c70 PZ |
12205 | if (IS_ERR(event)) { |
12206 | err = PTR_ERR(event); | |
12207 | goto err; | |
12208 | } | |
d859e29f | 12209 | |
f8697762 | 12210 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 12211 | event->owner = TASK_TOMBSTONE; |
f8697762 | 12212 | |
f25d8ba9 AS |
12213 | /* |
12214 | * Get the target context (task or percpu): | |
12215 | */ | |
4af57ef2 | 12216 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
12217 | if (IS_ERR(ctx)) { |
12218 | err = PTR_ERR(ctx); | |
c3f00c70 | 12219 | goto err_free; |
d859e29f | 12220 | } |
fb0459d7 | 12221 | |
fb0459d7 AV |
12222 | WARN_ON_ONCE(ctx->parent_ctx); |
12223 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
12224 | if (ctx->task == TASK_TOMBSTONE) { |
12225 | err = -ESRCH; | |
12226 | goto err_unlock; | |
12227 | } | |
12228 | ||
a63fbed7 TG |
12229 | if (!task) { |
12230 | /* | |
12231 | * Check if the @cpu we're creating an event for is online. | |
12232 | * | |
12233 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
12234 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
12235 | */ | |
12236 | struct perf_cpu_context *cpuctx = | |
12237 | container_of(ctx, struct perf_cpu_context, ctx); | |
12238 | if (!cpuctx->online) { | |
12239 | err = -ENODEV; | |
12240 | goto err_unlock; | |
12241 | } | |
12242 | } | |
12243 | ||
bed5b25a | 12244 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 12245 | err = -EBUSY; |
84c4e620 | 12246 | goto err_unlock; |
bed5b25a AS |
12247 | } |
12248 | ||
4ce54af8 | 12249 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 12250 | perf_unpin_context(ctx); |
fb0459d7 AV |
12251 | mutex_unlock(&ctx->mutex); |
12252 | ||
fb0459d7 AV |
12253 | return event; |
12254 | ||
84c4e620 PZ |
12255 | err_unlock: |
12256 | mutex_unlock(&ctx->mutex); | |
12257 | perf_unpin_context(ctx); | |
12258 | put_ctx(ctx); | |
c3f00c70 PZ |
12259 | err_free: |
12260 | free_event(event); | |
12261 | err: | |
c6567f64 | 12262 | return ERR_PTR(err); |
9b51f66d | 12263 | } |
fb0459d7 | 12264 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 12265 | |
0cda4c02 YZ |
12266 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
12267 | { | |
12268 | struct perf_event_context *src_ctx; | |
12269 | struct perf_event_context *dst_ctx; | |
12270 | struct perf_event *event, *tmp; | |
12271 | LIST_HEAD(events); | |
12272 | ||
12273 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
12274 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
12275 | ||
f63a8daa PZ |
12276 | /* |
12277 | * See perf_event_ctx_lock() for comments on the details | |
12278 | * of swizzling perf_event::ctx. | |
12279 | */ | |
12280 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
12281 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12282 | event_entry) { | |
45a0e07a | 12283 | perf_remove_from_context(event, 0); |
9a545de0 | 12284 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12285 | put_ctx(src_ctx); |
9886167d | 12286 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12287 | } |
0cda4c02 | 12288 | |
8f95b435 PZI |
12289 | /* |
12290 | * Wait for the events to quiesce before re-instating them. | |
12291 | */ | |
0cda4c02 YZ |
12292 | synchronize_rcu(); |
12293 | ||
8f95b435 PZI |
12294 | /* |
12295 | * Re-instate events in 2 passes. | |
12296 | * | |
12297 | * Skip over group leaders and only install siblings on this first | |
12298 | * pass, siblings will not get enabled without a leader, however a | |
12299 | * leader will enable its siblings, even if those are still on the old | |
12300 | * context. | |
12301 | */ | |
12302 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12303 | if (event->group_leader == event) | |
12304 | continue; | |
12305 | ||
12306 | list_del(&event->migrate_entry); | |
12307 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12308 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12309 | account_event_cpu(event, dst_cpu); | |
12310 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12311 | get_ctx(dst_ctx); | |
12312 | } | |
12313 | ||
12314 | /* | |
12315 | * Once all the siblings are setup properly, install the group leaders | |
12316 | * to make it go. | |
12317 | */ | |
9886167d PZ |
12318 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12319 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12320 | if (event->state >= PERF_EVENT_STATE_OFF) |
12321 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12322 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12323 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12324 | get_ctx(dst_ctx); | |
12325 | } | |
12326 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12327 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12328 | } |
12329 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12330 | ||
cdd6c482 | 12331 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 12332 | struct task_struct *child) |
d859e29f | 12333 | { |
cdd6c482 | 12334 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12335 | u64 child_val; |
d859e29f | 12336 | |
cdd6c482 IM |
12337 | if (child_event->attr.inherit_stat) |
12338 | perf_event_read_event(child_event, child); | |
38b200d6 | 12339 | |
b5e58793 | 12340 | child_val = perf_event_count(child_event); |
d859e29f PM |
12341 | |
12342 | /* | |
12343 | * Add back the child's count to the parent's count: | |
12344 | */ | |
a6e6dea6 | 12345 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12346 | atomic64_add(child_event->total_time_enabled, |
12347 | &parent_event->child_total_time_enabled); | |
12348 | atomic64_add(child_event->total_time_running, | |
12349 | &parent_event->child_total_time_running); | |
d859e29f PM |
12350 | } |
12351 | ||
9b51f66d | 12352 | static void |
8ba289b8 PZ |
12353 | perf_event_exit_event(struct perf_event *child_event, |
12354 | struct perf_event_context *child_ctx, | |
12355 | struct task_struct *child) | |
9b51f66d | 12356 | { |
8ba289b8 PZ |
12357 | struct perf_event *parent_event = child_event->parent; |
12358 | ||
1903d50c PZ |
12359 | /* |
12360 | * Do not destroy the 'original' grouping; because of the context | |
12361 | * switch optimization the original events could've ended up in a | |
12362 | * random child task. | |
12363 | * | |
12364 | * If we were to destroy the original group, all group related | |
12365 | * operations would cease to function properly after this random | |
12366 | * child dies. | |
12367 | * | |
12368 | * Do destroy all inherited groups, we don't care about those | |
12369 | * and being thorough is better. | |
12370 | */ | |
32132a3d PZ |
12371 | raw_spin_lock_irq(&child_ctx->lock); |
12372 | WARN_ON_ONCE(child_ctx->is_active); | |
12373 | ||
8ba289b8 | 12374 | if (parent_event) |
32132a3d PZ |
12375 | perf_group_detach(child_event); |
12376 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 12377 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 12378 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 12379 | |
9b51f66d | 12380 | /* |
8ba289b8 | 12381 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 12382 | */ |
8ba289b8 | 12383 | if (!parent_event) { |
179033b3 | 12384 | perf_event_wakeup(child_event); |
8ba289b8 | 12385 | return; |
4bcf349a | 12386 | } |
8ba289b8 PZ |
12387 | /* |
12388 | * Child events can be cleaned up. | |
12389 | */ | |
12390 | ||
12391 | sync_child_event(child_event, child); | |
12392 | ||
12393 | /* | |
12394 | * Remove this event from the parent's list | |
12395 | */ | |
12396 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
12397 | mutex_lock(&parent_event->child_mutex); | |
12398 | list_del_init(&child_event->child_list); | |
12399 | mutex_unlock(&parent_event->child_mutex); | |
12400 | ||
12401 | /* | |
12402 | * Kick perf_poll() for is_event_hup(). | |
12403 | */ | |
12404 | perf_event_wakeup(parent_event); | |
12405 | free_event(child_event); | |
12406 | put_event(parent_event); | |
9b51f66d IM |
12407 | } |
12408 | ||
8dc85d54 | 12409 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12410 | { |
211de6eb | 12411 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12412 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12413 | |
12414 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12415 | |
6a3351b6 | 12416 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12417 | if (!child_ctx) |
9b51f66d IM |
12418 | return; |
12419 | ||
ad3a37de | 12420 | /* |
6a3351b6 PZ |
12421 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12422 | * ctx::mutex over the entire thing. This serializes against almost | |
12423 | * everything that wants to access the ctx. | |
12424 | * | |
12425 | * The exception is sys_perf_event_open() / | |
12426 | * perf_event_create_kernel_count() which does find_get_context() | |
12427 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12428 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12429 | */ |
6a3351b6 | 12430 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12431 | |
12432 | /* | |
6a3351b6 PZ |
12433 | * In a single ctx::lock section, de-schedule the events and detach the |
12434 | * context from the task such that we cannot ever get it scheduled back | |
12435 | * in. | |
c93f7669 | 12436 | */ |
6a3351b6 | 12437 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12438 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12439 | |
71a851b4 | 12440 | /* |
63b6da39 PZ |
12441 | * Now that the context is inactive, destroy the task <-> ctx relation |
12442 | * and mark the context dead. | |
71a851b4 | 12443 | */ |
63b6da39 PZ |
12444 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12445 | put_ctx(child_ctx); /* cannot be last */ | |
12446 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12447 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12448 | |
211de6eb | 12449 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12450 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12451 | |
211de6eb PZ |
12452 | if (clone_ctx) |
12453 | put_ctx(clone_ctx); | |
4a1c0f26 | 12454 | |
9f498cc5 | 12455 | /* |
cdd6c482 IM |
12456 | * Report the task dead after unscheduling the events so that we |
12457 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12458 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12459 | */ |
cdd6c482 | 12460 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12461 | |
ebf905fc | 12462 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 12463 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 12464 | |
a63eaf34 PM |
12465 | mutex_unlock(&child_ctx->mutex); |
12466 | ||
12467 | put_ctx(child_ctx); | |
9b51f66d IM |
12468 | } |
12469 | ||
8dc85d54 PZ |
12470 | /* |
12471 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12472 | * |
69143038 | 12473 | * Can be called with exec_update_mutex held when called from |
96ecee29 | 12474 | * setup_new_exec(). |
8dc85d54 PZ |
12475 | */ |
12476 | void perf_event_exit_task(struct task_struct *child) | |
12477 | { | |
8882135b | 12478 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12479 | int ctxn; |
12480 | ||
8882135b PZ |
12481 | mutex_lock(&child->perf_event_mutex); |
12482 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12483 | owner_entry) { | |
12484 | list_del_init(&event->owner_entry); | |
12485 | ||
12486 | /* | |
12487 | * Ensure the list deletion is visible before we clear | |
12488 | * the owner, closes a race against perf_release() where | |
12489 | * we need to serialize on the owner->perf_event_mutex. | |
12490 | */ | |
f47c02c0 | 12491 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12492 | } |
12493 | mutex_unlock(&child->perf_event_mutex); | |
12494 | ||
8dc85d54 PZ |
12495 | for_each_task_context_nr(ctxn) |
12496 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12497 | |
12498 | /* | |
12499 | * The perf_event_exit_task_context calls perf_event_task | |
12500 | * with child's task_ctx, which generates EXIT events for | |
12501 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12502 | * At this point we need to send EXIT events to cpu contexts. | |
12503 | */ | |
12504 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12505 | } |
12506 | ||
889ff015 FW |
12507 | static void perf_free_event(struct perf_event *event, |
12508 | struct perf_event_context *ctx) | |
12509 | { | |
12510 | struct perf_event *parent = event->parent; | |
12511 | ||
12512 | if (WARN_ON_ONCE(!parent)) | |
12513 | return; | |
12514 | ||
12515 | mutex_lock(&parent->child_mutex); | |
12516 | list_del_init(&event->child_list); | |
12517 | mutex_unlock(&parent->child_mutex); | |
12518 | ||
a6fa941d | 12519 | put_event(parent); |
889ff015 | 12520 | |
652884fe | 12521 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12522 | perf_group_detach(event); |
889ff015 | 12523 | list_del_event(event, ctx); |
652884fe | 12524 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12525 | free_event(event); |
12526 | } | |
12527 | ||
bbbee908 | 12528 | /* |
1cf8dfe8 PZ |
12529 | * Free a context as created by inheritance by perf_event_init_task() below, |
12530 | * used by fork() in case of fail. | |
652884fe | 12531 | * |
1cf8dfe8 PZ |
12532 | * Even though the task has never lived, the context and events have been |
12533 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12534 | */ |
cdd6c482 | 12535 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12536 | { |
8dc85d54 | 12537 | struct perf_event_context *ctx; |
cdd6c482 | 12538 | struct perf_event *event, *tmp; |
8dc85d54 | 12539 | int ctxn; |
bbbee908 | 12540 | |
8dc85d54 PZ |
12541 | for_each_task_context_nr(ctxn) { |
12542 | ctx = task->perf_event_ctxp[ctxn]; | |
12543 | if (!ctx) | |
12544 | continue; | |
bbbee908 | 12545 | |
8dc85d54 | 12546 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12547 | raw_spin_lock_irq(&ctx->lock); |
12548 | /* | |
12549 | * Destroy the task <-> ctx relation and mark the context dead. | |
12550 | * | |
12551 | * This is important because even though the task hasn't been | |
12552 | * exposed yet the context has been (through child_list). | |
12553 | */ | |
12554 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12555 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12556 | put_task_struct(task); /* cannot be last */ | |
12557 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12558 | |
15121c78 | 12559 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12560 | perf_free_event(event, ctx); |
bbbee908 | 12561 | |
8dc85d54 | 12562 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12563 | |
12564 | /* | |
12565 | * perf_event_release_kernel() could've stolen some of our | |
12566 | * child events and still have them on its free_list. In that | |
12567 | * case we must wait for these events to have been freed (in | |
12568 | * particular all their references to this task must've been | |
12569 | * dropped). | |
12570 | * | |
12571 | * Without this copy_process() will unconditionally free this | |
12572 | * task (irrespective of its reference count) and | |
12573 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12574 | * use-after-free. | |
12575 | * | |
12576 | * Wait for all events to drop their context reference. | |
12577 | */ | |
12578 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12579 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12580 | } |
889ff015 FW |
12581 | } |
12582 | ||
4e231c79 PZ |
12583 | void perf_event_delayed_put(struct task_struct *task) |
12584 | { | |
12585 | int ctxn; | |
12586 | ||
12587 | for_each_task_context_nr(ctxn) | |
12588 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12589 | } | |
12590 | ||
e03e7ee3 | 12591 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12592 | { |
02e5ad97 | 12593 | struct file *file = fget(fd); |
e03e7ee3 AS |
12594 | if (!file) |
12595 | return ERR_PTR(-EBADF); | |
ffe8690c | 12596 | |
e03e7ee3 AS |
12597 | if (file->f_op != &perf_fops) { |
12598 | fput(file); | |
12599 | return ERR_PTR(-EBADF); | |
12600 | } | |
ffe8690c | 12601 | |
e03e7ee3 | 12602 | return file; |
ffe8690c KX |
12603 | } |
12604 | ||
f8d959a5 YS |
12605 | const struct perf_event *perf_get_event(struct file *file) |
12606 | { | |
12607 | if (file->f_op != &perf_fops) | |
12608 | return ERR_PTR(-EINVAL); | |
12609 | ||
12610 | return file->private_data; | |
12611 | } | |
12612 | ||
ffe8690c KX |
12613 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12614 | { | |
12615 | if (!event) | |
12616 | return ERR_PTR(-EINVAL); | |
12617 | ||
12618 | return &event->attr; | |
12619 | } | |
12620 | ||
97dee4f3 | 12621 | /* |
788faab7 | 12622 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12623 | * |
12624 | * Returns: | |
12625 | * - valid pointer on success | |
12626 | * - NULL for orphaned events | |
12627 | * - IS_ERR() on error | |
97dee4f3 PZ |
12628 | */ |
12629 | static struct perf_event * | |
12630 | inherit_event(struct perf_event *parent_event, | |
12631 | struct task_struct *parent, | |
12632 | struct perf_event_context *parent_ctx, | |
12633 | struct task_struct *child, | |
12634 | struct perf_event *group_leader, | |
12635 | struct perf_event_context *child_ctx) | |
12636 | { | |
8ca2bd41 | 12637 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12638 | struct perf_event *child_event; |
cee010ec | 12639 | unsigned long flags; |
97dee4f3 PZ |
12640 | |
12641 | /* | |
12642 | * Instead of creating recursive hierarchies of events, | |
12643 | * we link inherited events back to the original parent, | |
12644 | * which has a filp for sure, which we use as the reference | |
12645 | * count: | |
12646 | */ | |
12647 | if (parent_event->parent) | |
12648 | parent_event = parent_event->parent; | |
12649 | ||
12650 | child_event = perf_event_alloc(&parent_event->attr, | |
12651 | parent_event->cpu, | |
d580ff86 | 12652 | child, |
97dee4f3 | 12653 | group_leader, parent_event, |
79dff51e | 12654 | NULL, NULL, -1); |
97dee4f3 PZ |
12655 | if (IS_ERR(child_event)) |
12656 | return child_event; | |
a6fa941d | 12657 | |
313ccb96 JO |
12658 | |
12659 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12660 | !child_ctx->task_ctx_data) { | |
12661 | struct pmu *pmu = child_event->pmu; | |
12662 | ||
ff9ff926 | 12663 | child_ctx->task_ctx_data = alloc_task_ctx_data(pmu); |
313ccb96 JO |
12664 | if (!child_ctx->task_ctx_data) { |
12665 | free_event(child_event); | |
697d8778 | 12666 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12667 | } |
12668 | } | |
12669 | ||
c6e5b732 PZ |
12670 | /* |
12671 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12672 | * must be under the same lock in order to serialize against | |
12673 | * perf_event_release_kernel(), such that either we must observe | |
12674 | * is_orphaned_event() or they will observe us on the child_list. | |
12675 | */ | |
12676 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12677 | if (is_orphaned_event(parent_event) || |
12678 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12679 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12680 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12681 | free_event(child_event); |
12682 | return NULL; | |
12683 | } | |
12684 | ||
97dee4f3 PZ |
12685 | get_ctx(child_ctx); |
12686 | ||
12687 | /* | |
12688 | * Make the child state follow the state of the parent event, | |
12689 | * not its attr.disabled bit. We hold the parent's mutex, | |
12690 | * so we won't race with perf_event_{en, dis}able_family. | |
12691 | */ | |
1929def9 | 12692 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12693 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12694 | else | |
12695 | child_event->state = PERF_EVENT_STATE_OFF; | |
12696 | ||
12697 | if (parent_event->attr.freq) { | |
12698 | u64 sample_period = parent_event->hw.sample_period; | |
12699 | struct hw_perf_event *hwc = &child_event->hw; | |
12700 | ||
12701 | hwc->sample_period = sample_period; | |
12702 | hwc->last_period = sample_period; | |
12703 | ||
12704 | local64_set(&hwc->period_left, sample_period); | |
12705 | } | |
12706 | ||
12707 | child_event->ctx = child_ctx; | |
12708 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12709 | child_event->overflow_handler_context |
12710 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12711 | |
614b6780 TG |
12712 | /* |
12713 | * Precalculate sample_data sizes | |
12714 | */ | |
12715 | perf_event__header_size(child_event); | |
6844c09d | 12716 | perf_event__id_header_size(child_event); |
614b6780 | 12717 | |
97dee4f3 PZ |
12718 | /* |
12719 | * Link it up in the child's context: | |
12720 | */ | |
cee010ec | 12721 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12722 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12723 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12724 | |
97dee4f3 PZ |
12725 | /* |
12726 | * Link this into the parent event's child list | |
12727 | */ | |
97dee4f3 PZ |
12728 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12729 | mutex_unlock(&parent_event->child_mutex); | |
12730 | ||
12731 | return child_event; | |
12732 | } | |
12733 | ||
d8a8cfc7 PZ |
12734 | /* |
12735 | * Inherits an event group. | |
12736 | * | |
12737 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12738 | * This matches with perf_event_release_kernel() removing all child events. | |
12739 | * | |
12740 | * Returns: | |
12741 | * - 0 on success | |
12742 | * - <0 on error | |
12743 | */ | |
97dee4f3 PZ |
12744 | static int inherit_group(struct perf_event *parent_event, |
12745 | struct task_struct *parent, | |
12746 | struct perf_event_context *parent_ctx, | |
12747 | struct task_struct *child, | |
12748 | struct perf_event_context *child_ctx) | |
12749 | { | |
12750 | struct perf_event *leader; | |
12751 | struct perf_event *sub; | |
12752 | struct perf_event *child_ctr; | |
12753 | ||
12754 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12755 | child, NULL, child_ctx); | |
12756 | if (IS_ERR(leader)) | |
12757 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12758 | /* |
12759 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12760 | * case inherit_event() will create individual events, similar to what | |
12761 | * perf_group_detach() would do anyway. | |
12762 | */ | |
edb39592 | 12763 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12764 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12765 | child, leader, child_ctx); | |
12766 | if (IS_ERR(child_ctr)) | |
12767 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12768 | |
00496fe5 | 12769 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12770 | !perf_get_aux_event(child_ctr, leader)) |
12771 | return -EINVAL; | |
97dee4f3 PZ |
12772 | } |
12773 | return 0; | |
889ff015 FW |
12774 | } |
12775 | ||
d8a8cfc7 PZ |
12776 | /* |
12777 | * Creates the child task context and tries to inherit the event-group. | |
12778 | * | |
12779 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12780 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12781 | * consistent with perf_event_release_kernel() removing all child events. | |
12782 | * | |
12783 | * Returns: | |
12784 | * - 0 on success | |
12785 | * - <0 on error | |
12786 | */ | |
889ff015 FW |
12787 | static int |
12788 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12789 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12790 | struct task_struct *child, int ctxn, |
889ff015 FW |
12791 | int *inherited_all) |
12792 | { | |
12793 | int ret; | |
8dc85d54 | 12794 | struct perf_event_context *child_ctx; |
889ff015 FW |
12795 | |
12796 | if (!event->attr.inherit) { | |
12797 | *inherited_all = 0; | |
12798 | return 0; | |
bbbee908 PZ |
12799 | } |
12800 | ||
fe4b04fa | 12801 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12802 | if (!child_ctx) { |
12803 | /* | |
12804 | * This is executed from the parent task context, so | |
12805 | * inherit events that have been marked for cloning. | |
12806 | * First allocate and initialize a context for the | |
12807 | * child. | |
12808 | */ | |
734df5ab | 12809 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12810 | if (!child_ctx) |
12811 | return -ENOMEM; | |
bbbee908 | 12812 | |
8dc85d54 | 12813 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12814 | } |
12815 | ||
12816 | ret = inherit_group(event, parent, parent_ctx, | |
12817 | child, child_ctx); | |
12818 | ||
12819 | if (ret) | |
12820 | *inherited_all = 0; | |
12821 | ||
12822 | return ret; | |
bbbee908 PZ |
12823 | } |
12824 | ||
9b51f66d | 12825 | /* |
cdd6c482 | 12826 | * Initialize the perf_event context in task_struct |
9b51f66d | 12827 | */ |
985c8dcb | 12828 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12829 | { |
889ff015 | 12830 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12831 | struct perf_event_context *cloned_ctx; |
12832 | struct perf_event *event; | |
9b51f66d | 12833 | struct task_struct *parent = current; |
564c2b21 | 12834 | int inherited_all = 1; |
dddd3379 | 12835 | unsigned long flags; |
6ab423e0 | 12836 | int ret = 0; |
9b51f66d | 12837 | |
8dc85d54 | 12838 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12839 | return 0; |
12840 | ||
ad3a37de | 12841 | /* |
25346b93 PM |
12842 | * If the parent's context is a clone, pin it so it won't get |
12843 | * swapped under us. | |
ad3a37de | 12844 | */ |
8dc85d54 | 12845 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12846 | if (!parent_ctx) |
12847 | return 0; | |
25346b93 | 12848 | |
ad3a37de PM |
12849 | /* |
12850 | * No need to check if parent_ctx != NULL here; since we saw | |
12851 | * it non-NULL earlier, the only reason for it to become NULL | |
12852 | * is if we exit, and since we're currently in the middle of | |
12853 | * a fork we can't be exiting at the same time. | |
12854 | */ | |
ad3a37de | 12855 | |
9b51f66d IM |
12856 | /* |
12857 | * Lock the parent list. No need to lock the child - not PID | |
12858 | * hashed yet and not running, so nobody can access it. | |
12859 | */ | |
d859e29f | 12860 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12861 | |
12862 | /* | |
12863 | * We dont have to disable NMIs - we are only looking at | |
12864 | * the list, not manipulating it: | |
12865 | */ | |
6e6804d2 | 12866 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12867 | ret = inherit_task_group(event, parent, parent_ctx, |
12868 | child, ctxn, &inherited_all); | |
889ff015 | 12869 | if (ret) |
e7cc4865 | 12870 | goto out_unlock; |
889ff015 | 12871 | } |
b93f7978 | 12872 | |
dddd3379 TG |
12873 | /* |
12874 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12875 | * to allocations, but we need to prevent rotation because | |
12876 | * rotate_ctx() will change the list from interrupt context. | |
12877 | */ | |
12878 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12879 | parent_ctx->rotate_disable = 1; | |
12880 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12881 | ||
6e6804d2 | 12882 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12883 | ret = inherit_task_group(event, parent, parent_ctx, |
12884 | child, ctxn, &inherited_all); | |
889ff015 | 12885 | if (ret) |
e7cc4865 | 12886 | goto out_unlock; |
564c2b21 PM |
12887 | } |
12888 | ||
dddd3379 TG |
12889 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12890 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12891 | |
8dc85d54 | 12892 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12893 | |
05cbaa28 | 12894 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12895 | /* |
12896 | * Mark the child context as a clone of the parent | |
12897 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12898 | * |
12899 | * Note that if the parent is a clone, the holding of | |
12900 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12901 | */ |
c5ed5145 | 12902 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12903 | if (cloned_ctx) { |
12904 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12905 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12906 | } else { |
12907 | child_ctx->parent_ctx = parent_ctx; | |
12908 | child_ctx->parent_gen = parent_ctx->generation; | |
12909 | } | |
12910 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12911 | } |
12912 | ||
c5ed5145 | 12913 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12914 | out_unlock: |
d859e29f | 12915 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12916 | |
25346b93 | 12917 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12918 | put_ctx(parent_ctx); |
ad3a37de | 12919 | |
6ab423e0 | 12920 | return ret; |
9b51f66d IM |
12921 | } |
12922 | ||
8dc85d54 PZ |
12923 | /* |
12924 | * Initialize the perf_event context in task_struct | |
12925 | */ | |
12926 | int perf_event_init_task(struct task_struct *child) | |
12927 | { | |
12928 | int ctxn, ret; | |
12929 | ||
8550d7cb ON |
12930 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12931 | mutex_init(&child->perf_event_mutex); | |
12932 | INIT_LIST_HEAD(&child->perf_event_list); | |
12933 | ||
8dc85d54 PZ |
12934 | for_each_task_context_nr(ctxn) { |
12935 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12936 | if (ret) { |
12937 | perf_event_free_task(child); | |
8dc85d54 | 12938 | return ret; |
6c72e350 | 12939 | } |
8dc85d54 PZ |
12940 | } |
12941 | ||
12942 | return 0; | |
12943 | } | |
12944 | ||
220b140b PM |
12945 | static void __init perf_event_init_all_cpus(void) |
12946 | { | |
b28ab83c | 12947 | struct swevent_htable *swhash; |
220b140b | 12948 | int cpu; |
220b140b | 12949 | |
a63fbed7 TG |
12950 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12951 | ||
220b140b | 12952 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12953 | swhash = &per_cpu(swevent_htable, cpu); |
12954 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12955 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12956 | |
12957 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12958 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12959 | |
058fe1c0 DCC |
12960 | #ifdef CONFIG_CGROUP_PERF |
12961 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12962 | #endif | |
220b140b PM |
12963 | } |
12964 | } | |
12965 | ||
d18bf422 | 12966 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12967 | { |
108b02cf | 12968 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12969 | |
b28ab83c | 12970 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12971 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12972 | struct swevent_hlist *hlist; |
12973 | ||
b28ab83c PZ |
12974 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12975 | WARN_ON(!hlist); | |
12976 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12977 | } |
b28ab83c | 12978 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12979 | } |
12980 | ||
2965faa5 | 12981 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12982 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12983 | { |
108b02cf | 12984 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12985 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12986 | struct perf_event *event; | |
0793a61d | 12987 | |
fae3fde6 | 12988 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12989 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12990 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12991 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12992 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12993 | } |
108b02cf PZ |
12994 | |
12995 | static void perf_event_exit_cpu_context(int cpu) | |
12996 | { | |
a63fbed7 | 12997 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12998 | struct perf_event_context *ctx; |
12999 | struct pmu *pmu; | |
108b02cf | 13000 | |
a63fbed7 TG |
13001 | mutex_lock(&pmus_lock); |
13002 | list_for_each_entry(pmu, &pmus, entry) { | |
13003 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13004 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
13005 | |
13006 | mutex_lock(&ctx->mutex); | |
13007 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 13008 | cpuctx->online = 0; |
108b02cf PZ |
13009 | mutex_unlock(&ctx->mutex); |
13010 | } | |
a63fbed7 TG |
13011 | cpumask_clear_cpu(cpu, perf_online_mask); |
13012 | mutex_unlock(&pmus_lock); | |
108b02cf | 13013 | } |
00e16c3d TG |
13014 | #else |
13015 | ||
13016 | static void perf_event_exit_cpu_context(int cpu) { } | |
13017 | ||
13018 | #endif | |
108b02cf | 13019 | |
a63fbed7 TG |
13020 | int perf_event_init_cpu(unsigned int cpu) |
13021 | { | |
13022 | struct perf_cpu_context *cpuctx; | |
13023 | struct perf_event_context *ctx; | |
13024 | struct pmu *pmu; | |
13025 | ||
13026 | perf_swevent_init_cpu(cpu); | |
13027 | ||
13028 | mutex_lock(&pmus_lock); | |
13029 | cpumask_set_cpu(cpu, perf_online_mask); | |
13030 | list_for_each_entry(pmu, &pmus, entry) { | |
13031 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
13032 | ctx = &cpuctx->ctx; | |
13033 | ||
13034 | mutex_lock(&ctx->mutex); | |
13035 | cpuctx->online = 1; | |
13036 | mutex_unlock(&ctx->mutex); | |
13037 | } | |
13038 | mutex_unlock(&pmus_lock); | |
13039 | ||
13040 | return 0; | |
13041 | } | |
13042 | ||
00e16c3d | 13043 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 13044 | { |
e3703f8c | 13045 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 13046 | return 0; |
0793a61d | 13047 | } |
0793a61d | 13048 | |
c277443c PZ |
13049 | static int |
13050 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
13051 | { | |
13052 | int cpu; | |
13053 | ||
13054 | for_each_online_cpu(cpu) | |
13055 | perf_event_exit_cpu(cpu); | |
13056 | ||
13057 | return NOTIFY_OK; | |
13058 | } | |
13059 | ||
13060 | /* | |
13061 | * Run the perf reboot notifier at the very last possible moment so that | |
13062 | * the generic watchdog code runs as long as possible. | |
13063 | */ | |
13064 | static struct notifier_block perf_reboot_notifier = { | |
13065 | .notifier_call = perf_reboot, | |
13066 | .priority = INT_MIN, | |
13067 | }; | |
13068 | ||
cdd6c482 | 13069 | void __init perf_event_init(void) |
0793a61d | 13070 | { |
3c502e7a JW |
13071 | int ret; |
13072 | ||
2e80a82a PZ |
13073 | idr_init(&pmu_idr); |
13074 | ||
220b140b | 13075 | perf_event_init_all_cpus(); |
b0a873eb | 13076 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
13077 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
13078 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
13079 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 13080 | perf_tp_register(); |
00e16c3d | 13081 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 13082 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
13083 | |
13084 | ret = init_hw_breakpoint(); | |
13085 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 13086 | |
b01c3a00 JO |
13087 | /* |
13088 | * Build time assertion that we keep the data_head at the intended | |
13089 | * location. IOW, validation we got the __reserved[] size right. | |
13090 | */ | |
13091 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
13092 | != 1024); | |
0793a61d | 13093 | } |
abe43400 | 13094 | |
fd979c01 CS |
13095 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
13096 | char *page) | |
13097 | { | |
13098 | struct perf_pmu_events_attr *pmu_attr = | |
13099 | container_of(attr, struct perf_pmu_events_attr, attr); | |
13100 | ||
13101 | if (pmu_attr->event_str) | |
13102 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
13103 | ||
13104 | return 0; | |
13105 | } | |
675965b0 | 13106 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 13107 | |
abe43400 PZ |
13108 | static int __init perf_event_sysfs_init(void) |
13109 | { | |
13110 | struct pmu *pmu; | |
13111 | int ret; | |
13112 | ||
13113 | mutex_lock(&pmus_lock); | |
13114 | ||
13115 | ret = bus_register(&pmu_bus); | |
13116 | if (ret) | |
13117 | goto unlock; | |
13118 | ||
13119 | list_for_each_entry(pmu, &pmus, entry) { | |
13120 | if (!pmu->name || pmu->type < 0) | |
13121 | continue; | |
13122 | ||
13123 | ret = pmu_dev_alloc(pmu); | |
13124 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
13125 | } | |
13126 | pmu_bus_running = 1; | |
13127 | ret = 0; | |
13128 | ||
13129 | unlock: | |
13130 | mutex_unlock(&pmus_lock); | |
13131 | ||
13132 | return ret; | |
13133 | } | |
13134 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
13135 | |
13136 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
13137 | static struct cgroup_subsys_state * |
13138 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
13139 | { |
13140 | struct perf_cgroup *jc; | |
e5d1367f | 13141 | |
1b15d055 | 13142 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
13143 | if (!jc) |
13144 | return ERR_PTR(-ENOMEM); | |
13145 | ||
e5d1367f SE |
13146 | jc->info = alloc_percpu(struct perf_cgroup_info); |
13147 | if (!jc->info) { | |
13148 | kfree(jc); | |
13149 | return ERR_PTR(-ENOMEM); | |
13150 | } | |
13151 | ||
e5d1367f SE |
13152 | return &jc->css; |
13153 | } | |
13154 | ||
eb95419b | 13155 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 13156 | { |
eb95419b TH |
13157 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
13158 | ||
e5d1367f SE |
13159 | free_percpu(jc->info); |
13160 | kfree(jc); | |
13161 | } | |
13162 | ||
96aaab68 NK |
13163 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
13164 | { | |
13165 | perf_event_cgroup(css->cgroup); | |
13166 | return 0; | |
13167 | } | |
13168 | ||
e5d1367f SE |
13169 | static int __perf_cgroup_move(void *info) |
13170 | { | |
13171 | struct task_struct *task = info; | |
ddaaf4e2 | 13172 | rcu_read_lock(); |
e5d1367f | 13173 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 13174 | rcu_read_unlock(); |
e5d1367f SE |
13175 | return 0; |
13176 | } | |
13177 | ||
1f7dd3e5 | 13178 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 13179 | { |
bb9d97b6 | 13180 | struct task_struct *task; |
1f7dd3e5 | 13181 | struct cgroup_subsys_state *css; |
bb9d97b6 | 13182 | |
1f7dd3e5 | 13183 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 13184 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
13185 | } |
13186 | ||
073219e9 | 13187 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
13188 | .css_alloc = perf_cgroup_css_alloc, |
13189 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 13190 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 13191 | .attach = perf_cgroup_attach, |
968ebff1 TH |
13192 | /* |
13193 | * Implicitly enable on dfl hierarchy so that perf events can | |
13194 | * always be filtered by cgroup2 path as long as perf_event | |
13195 | * controller is not mounted on a legacy hierarchy. | |
13196 | */ | |
13197 | .implicit_on_dfl = true, | |
8cfd8147 | 13198 | .threaded = true, |
e5d1367f SE |
13199 | }; |
13200 | #endif /* CONFIG_CGROUP_PERF */ |