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Commit | Line | Data |
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0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
7b732a75 | 8 | * |
57c0c15b | 9 | * For licensing details see kernel-base/COPYING |
0793a61d TG |
10 | */ |
11 | ||
12 | #include <linux/fs.h> | |
b9cacc7b | 13 | #include <linux/mm.h> |
0793a61d TG |
14 | #include <linux/cpu.h> |
15 | #include <linux/smp.h> | |
2e80a82a | 16 | #include <linux/idr.h> |
04289bb9 | 17 | #include <linux/file.h> |
0793a61d | 18 | #include <linux/poll.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
76e1d904 | 20 | #include <linux/hash.h> |
12351ef8 | 21 | #include <linux/tick.h> |
0793a61d | 22 | #include <linux/sysfs.h> |
22a4f650 | 23 | #include <linux/dcache.h> |
0793a61d | 24 | #include <linux/percpu.h> |
22a4f650 | 25 | #include <linux/ptrace.h> |
c277443c | 26 | #include <linux/reboot.h> |
b9cacc7b | 27 | #include <linux/vmstat.h> |
abe43400 | 28 | #include <linux/device.h> |
6e5fdeed | 29 | #include <linux/export.h> |
906010b2 | 30 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
31 | #include <linux/hardirq.h> |
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> | |
0793a61d | 49 | |
76369139 FW |
50 | #include "internal.h" |
51 | ||
4e193bd4 TB |
52 | #include <asm/irq_regs.h> |
53 | ||
272325c4 PZ |
54 | typedef int (*remote_function_f)(void *); |
55 | ||
fe4b04fa | 56 | struct remote_function_call { |
e7e7ee2e | 57 | struct task_struct *p; |
272325c4 | 58 | remote_function_f func; |
e7e7ee2e IM |
59 | void *info; |
60 | int ret; | |
fe4b04fa PZ |
61 | }; |
62 | ||
63 | static void remote_function(void *data) | |
64 | { | |
65 | struct remote_function_call *tfc = data; | |
66 | struct task_struct *p = tfc->p; | |
67 | ||
68 | if (p) { | |
0da4cf3e PZ |
69 | /* -EAGAIN */ |
70 | if (task_cpu(p) != smp_processor_id()) | |
71 | return; | |
72 | ||
73 | /* | |
74 | * Now that we're on right CPU with IRQs disabled, we can test | |
75 | * if we hit the right task without races. | |
76 | */ | |
77 | ||
78 | tfc->ret = -ESRCH; /* No such (running) process */ | |
79 | if (p != current) | |
fe4b04fa PZ |
80 | return; |
81 | } | |
82 | ||
83 | tfc->ret = tfc->func(tfc->info); | |
84 | } | |
85 | ||
86 | /** | |
87 | * task_function_call - call a function on the cpu on which a task runs | |
88 | * @p: the task to evaluate | |
89 | * @func: the function to be called | |
90 | * @info: the function call argument | |
91 | * | |
92 | * Calls the function @func when the task is currently running. This might | |
93 | * be on the current CPU, which just calls the function directly | |
94 | * | |
95 | * returns: @func return value, or | |
96 | * -ESRCH - when the process isn't running | |
97 | * -EAGAIN - when the process moved away | |
98 | */ | |
99 | static int | |
272325c4 | 100 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
101 | { |
102 | struct remote_function_call data = { | |
e7e7ee2e IM |
103 | .p = p, |
104 | .func = func, | |
105 | .info = info, | |
0da4cf3e | 106 | .ret = -EAGAIN, |
fe4b04fa | 107 | }; |
0da4cf3e | 108 | int ret; |
fe4b04fa | 109 | |
0da4cf3e PZ |
110 | do { |
111 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
112 | if (!ret) | |
113 | ret = data.ret; | |
114 | } while (ret == -EAGAIN); | |
fe4b04fa | 115 | |
0da4cf3e | 116 | return ret; |
fe4b04fa PZ |
117 | } |
118 | ||
119 | /** | |
120 | * cpu_function_call - call a function on the cpu | |
121 | * @func: the function to be called | |
122 | * @info: the function call argument | |
123 | * | |
124 | * Calls the function @func on the remote cpu. | |
125 | * | |
126 | * returns: @func return value or -ENXIO when the cpu is offline | |
127 | */ | |
272325c4 | 128 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
129 | { |
130 | struct remote_function_call data = { | |
e7e7ee2e IM |
131 | .p = NULL, |
132 | .func = func, | |
133 | .info = info, | |
134 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
135 | }; |
136 | ||
137 | smp_call_function_single(cpu, remote_function, &data, 1); | |
138 | ||
139 | return data.ret; | |
140 | } | |
141 | ||
fae3fde6 PZ |
142 | static inline struct perf_cpu_context * |
143 | __get_cpu_context(struct perf_event_context *ctx) | |
144 | { | |
145 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
146 | } | |
147 | ||
148 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
149 | struct perf_event_context *ctx) | |
0017960f | 150 | { |
fae3fde6 PZ |
151 | raw_spin_lock(&cpuctx->ctx.lock); |
152 | if (ctx) | |
153 | raw_spin_lock(&ctx->lock); | |
154 | } | |
155 | ||
156 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
157 | struct perf_event_context *ctx) | |
158 | { | |
159 | if (ctx) | |
160 | raw_spin_unlock(&ctx->lock); | |
161 | raw_spin_unlock(&cpuctx->ctx.lock); | |
162 | } | |
163 | ||
63b6da39 PZ |
164 | #define TASK_TOMBSTONE ((void *)-1L) |
165 | ||
166 | static bool is_kernel_event(struct perf_event *event) | |
167 | { | |
f47c02c0 | 168 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
169 | } |
170 | ||
39a43640 PZ |
171 | /* |
172 | * On task ctx scheduling... | |
173 | * | |
174 | * When !ctx->nr_events a task context will not be scheduled. This means | |
175 | * we can disable the scheduler hooks (for performance) without leaving | |
176 | * pending task ctx state. | |
177 | * | |
178 | * This however results in two special cases: | |
179 | * | |
180 | * - removing the last event from a task ctx; this is relatively straight | |
181 | * forward and is done in __perf_remove_from_context. | |
182 | * | |
183 | * - adding the first event to a task ctx; this is tricky because we cannot | |
184 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
185 | * See perf_install_in_context(). | |
186 | * | |
39a43640 PZ |
187 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
188 | */ | |
189 | ||
fae3fde6 PZ |
190 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
191 | struct perf_event_context *, void *); | |
192 | ||
193 | struct event_function_struct { | |
194 | struct perf_event *event; | |
195 | event_f func; | |
196 | void *data; | |
197 | }; | |
198 | ||
199 | static int event_function(void *info) | |
200 | { | |
201 | struct event_function_struct *efs = info; | |
202 | struct perf_event *event = efs->event; | |
0017960f | 203 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
204 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
205 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 206 | int ret = 0; |
fae3fde6 PZ |
207 | |
208 | WARN_ON_ONCE(!irqs_disabled()); | |
209 | ||
63b6da39 | 210 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
211 | /* |
212 | * Since we do the IPI call without holding ctx->lock things can have | |
213 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
214 | */ |
215 | if (ctx->task) { | |
63b6da39 | 216 | if (ctx->task != current) { |
0da4cf3e | 217 | ret = -ESRCH; |
63b6da39 PZ |
218 | goto unlock; |
219 | } | |
fae3fde6 | 220 | |
fae3fde6 PZ |
221 | /* |
222 | * We only use event_function_call() on established contexts, | |
223 | * and event_function() is only ever called when active (or | |
224 | * rather, we'll have bailed in task_function_call() or the | |
225 | * above ctx->task != current test), therefore we must have | |
226 | * ctx->is_active here. | |
227 | */ | |
228 | WARN_ON_ONCE(!ctx->is_active); | |
229 | /* | |
230 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
231 | * match. | |
232 | */ | |
63b6da39 PZ |
233 | WARN_ON_ONCE(task_ctx != ctx); |
234 | } else { | |
235 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 236 | } |
63b6da39 | 237 | |
fae3fde6 | 238 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 239 | unlock: |
fae3fde6 PZ |
240 | perf_ctx_unlock(cpuctx, task_ctx); |
241 | ||
63b6da39 | 242 | return ret; |
fae3fde6 PZ |
243 | } |
244 | ||
fae3fde6 | 245 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
246 | { |
247 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 248 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
249 | struct event_function_struct efs = { |
250 | .event = event, | |
251 | .func = func, | |
252 | .data = data, | |
253 | }; | |
0017960f | 254 | |
c97f4736 PZ |
255 | if (!event->parent) { |
256 | /* | |
257 | * If this is a !child event, we must hold ctx::mutex to | |
258 | * stabilize the the event->ctx relation. See | |
259 | * perf_event_ctx_lock(). | |
260 | */ | |
261 | lockdep_assert_held(&ctx->mutex); | |
262 | } | |
0017960f PZ |
263 | |
264 | if (!task) { | |
fae3fde6 | 265 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
266 | return; |
267 | } | |
268 | ||
63b6da39 PZ |
269 | if (task == TASK_TOMBSTONE) |
270 | return; | |
271 | ||
a096309b | 272 | again: |
fae3fde6 | 273 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
274 | return; |
275 | ||
276 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
277 | /* |
278 | * Reload the task pointer, it might have been changed by | |
279 | * a concurrent perf_event_context_sched_out(). | |
280 | */ | |
281 | task = ctx->task; | |
a096309b PZ |
282 | if (task == TASK_TOMBSTONE) { |
283 | raw_spin_unlock_irq(&ctx->lock); | |
284 | return; | |
0017960f | 285 | } |
a096309b PZ |
286 | if (ctx->is_active) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | goto again; | |
289 | } | |
290 | func(event, NULL, ctx, data); | |
0017960f PZ |
291 | raw_spin_unlock_irq(&ctx->lock); |
292 | } | |
293 | ||
cca20946 PZ |
294 | /* |
295 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
296 | * are already disabled and we're on the right CPU. | |
297 | */ | |
298 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
299 | { | |
300 | struct perf_event_context *ctx = event->ctx; | |
301 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
302 | struct task_struct *task = READ_ONCE(ctx->task); | |
303 | struct perf_event_context *task_ctx = NULL; | |
304 | ||
305 | WARN_ON_ONCE(!irqs_disabled()); | |
306 | ||
307 | if (task) { | |
308 | if (task == TASK_TOMBSTONE) | |
309 | return; | |
310 | ||
311 | task_ctx = ctx; | |
312 | } | |
313 | ||
314 | perf_ctx_lock(cpuctx, task_ctx); | |
315 | ||
316 | task = ctx->task; | |
317 | if (task == TASK_TOMBSTONE) | |
318 | goto unlock; | |
319 | ||
320 | if (task) { | |
321 | /* | |
322 | * We must be either inactive or active and the right task, | |
323 | * otherwise we're screwed, since we cannot IPI to somewhere | |
324 | * else. | |
325 | */ | |
326 | if (ctx->is_active) { | |
327 | if (WARN_ON_ONCE(task != current)) | |
328 | goto unlock; | |
329 | ||
330 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
331 | goto unlock; | |
332 | } | |
333 | } else { | |
334 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
335 | } | |
336 | ||
337 | func(event, cpuctx, ctx, data); | |
338 | unlock: | |
339 | perf_ctx_unlock(cpuctx, task_ctx); | |
340 | } | |
341 | ||
e5d1367f SE |
342 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
343 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
344 | PERF_FLAG_PID_CGROUP |\ |
345 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 346 | |
bce38cd5 SE |
347 | /* |
348 | * branch priv levels that need permission checks | |
349 | */ | |
350 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
351 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
352 | PERF_SAMPLE_BRANCH_HV) | |
353 | ||
0b3fcf17 SE |
354 | enum event_type_t { |
355 | EVENT_FLEXIBLE = 0x1, | |
356 | EVENT_PINNED = 0x2, | |
3cbaa590 | 357 | EVENT_TIME = 0x4, |
487f05e1 AS |
358 | /* see ctx_resched() for details */ |
359 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
360 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
361 | }; | |
362 | ||
e5d1367f SE |
363 | /* |
364 | * perf_sched_events : >0 events exist | |
365 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
366 | */ | |
9107c89e PZ |
367 | |
368 | static void perf_sched_delayed(struct work_struct *work); | |
369 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
370 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
371 | static DEFINE_MUTEX(perf_sched_mutex); | |
372 | static atomic_t perf_sched_count; | |
373 | ||
e5d1367f | 374 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 375 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 376 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 377 | |
cdd6c482 IM |
378 | static atomic_t nr_mmap_events __read_mostly; |
379 | static atomic_t nr_comm_events __read_mostly; | |
380 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 381 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 382 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 383 | |
108b02cf PZ |
384 | static LIST_HEAD(pmus); |
385 | static DEFINE_MUTEX(pmus_lock); | |
386 | static struct srcu_struct pmus_srcu; | |
387 | ||
0764771d | 388 | /* |
cdd6c482 | 389 | * perf event paranoia level: |
0fbdea19 IM |
390 | * -1 - not paranoid at all |
391 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 392 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 393 | * 2 - disallow kernel profiling for unpriv |
0764771d | 394 | */ |
0161028b | 395 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 396 | |
20443384 FW |
397 | /* Minimum for 512 kiB + 1 user control page */ |
398 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
399 | |
400 | /* | |
cdd6c482 | 401 | * max perf event sample rate |
df58ab24 | 402 | */ |
14c63f17 DH |
403 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
404 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
405 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
406 | ||
407 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
408 | ||
409 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
410 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
411 | ||
d9494cb4 PZ |
412 | static int perf_sample_allowed_ns __read_mostly = |
413 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 414 | |
18ab2cd3 | 415 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
416 | { |
417 | u64 tmp = perf_sample_period_ns; | |
418 | ||
419 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
420 | tmp = div_u64(tmp, 100); |
421 | if (!tmp) | |
422 | tmp = 1; | |
423 | ||
424 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 425 | } |
163ec435 | 426 | |
9e630205 SE |
427 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
428 | ||
163ec435 PZ |
429 | int perf_proc_update_handler(struct ctl_table *table, int write, |
430 | void __user *buffer, size_t *lenp, | |
431 | loff_t *ppos) | |
432 | { | |
723478c8 | 433 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
434 | |
435 | if (ret || !write) | |
436 | return ret; | |
437 | ||
ab7fdefb KL |
438 | /* |
439 | * If throttling is disabled don't allow the write: | |
440 | */ | |
441 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
442 | sysctl_perf_cpu_time_max_percent == 0) | |
443 | return -EINVAL; | |
444 | ||
163ec435 | 445 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
446 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
447 | update_perf_cpu_limits(); | |
448 | ||
449 | return 0; | |
450 | } | |
451 | ||
452 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
453 | ||
454 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
455 | void __user *buffer, size_t *lenp, | |
456 | loff_t *ppos) | |
457 | { | |
458 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
459 | ||
460 | if (ret || !write) | |
461 | return ret; | |
462 | ||
b303e7c1 PZ |
463 | if (sysctl_perf_cpu_time_max_percent == 100 || |
464 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
465 | printk(KERN_WARNING |
466 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
467 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
468 | } else { | |
469 | update_perf_cpu_limits(); | |
470 | } | |
163ec435 PZ |
471 | |
472 | return 0; | |
473 | } | |
1ccd1549 | 474 | |
14c63f17 DH |
475 | /* |
476 | * perf samples are done in some very critical code paths (NMIs). | |
477 | * If they take too much CPU time, the system can lock up and not | |
478 | * get any real work done. This will drop the sample rate when | |
479 | * we detect that events are taking too long. | |
480 | */ | |
481 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 482 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 483 | |
91a612ee PZ |
484 | static u64 __report_avg; |
485 | static u64 __report_allowed; | |
486 | ||
6a02ad66 | 487 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 488 | { |
0d87d7ec | 489 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
490 | "perf: interrupt took too long (%lld > %lld), lowering " |
491 | "kernel.perf_event_max_sample_rate to %d\n", | |
492 | __report_avg, __report_allowed, | |
493 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
494 | } |
495 | ||
496 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
497 | ||
498 | void perf_sample_event_took(u64 sample_len_ns) | |
499 | { | |
91a612ee PZ |
500 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
501 | u64 running_len; | |
502 | u64 avg_len; | |
503 | u32 max; | |
14c63f17 | 504 | |
91a612ee | 505 | if (max_len == 0) |
14c63f17 DH |
506 | return; |
507 | ||
91a612ee PZ |
508 | /* Decay the counter by 1 average sample. */ |
509 | running_len = __this_cpu_read(running_sample_length); | |
510 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
511 | running_len += sample_len_ns; | |
512 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
513 | |
514 | /* | |
91a612ee PZ |
515 | * Note: this will be biased artifically low until we have |
516 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
517 | * from having to maintain a count. |
518 | */ | |
91a612ee PZ |
519 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
520 | if (avg_len <= max_len) | |
14c63f17 DH |
521 | return; |
522 | ||
91a612ee PZ |
523 | __report_avg = avg_len; |
524 | __report_allowed = max_len; | |
14c63f17 | 525 | |
91a612ee PZ |
526 | /* |
527 | * Compute a throttle threshold 25% below the current duration. | |
528 | */ | |
529 | avg_len += avg_len / 4; | |
530 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
531 | if (avg_len < max) | |
532 | max /= (u32)avg_len; | |
533 | else | |
534 | max = 1; | |
14c63f17 | 535 | |
91a612ee PZ |
536 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
537 | WRITE_ONCE(max_samples_per_tick, max); | |
538 | ||
539 | sysctl_perf_event_sample_rate = max * HZ; | |
540 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 541 | |
cd578abb | 542 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 543 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 544 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 545 | __report_avg, __report_allowed, |
cd578abb PZ |
546 | sysctl_perf_event_sample_rate); |
547 | } | |
14c63f17 DH |
548 | } |
549 | ||
cdd6c482 | 550 | static atomic64_t perf_event_id; |
a96bbc16 | 551 | |
0b3fcf17 SE |
552 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
553 | enum event_type_t event_type); | |
554 | ||
555 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
556 | enum event_type_t event_type, |
557 | struct task_struct *task); | |
558 | ||
559 | static void update_context_time(struct perf_event_context *ctx); | |
560 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 561 | |
cdd6c482 | 562 | void __weak perf_event_print_debug(void) { } |
0793a61d | 563 | |
84c79910 | 564 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 565 | { |
84c79910 | 566 | return "pmu"; |
0793a61d TG |
567 | } |
568 | ||
0b3fcf17 SE |
569 | static inline u64 perf_clock(void) |
570 | { | |
571 | return local_clock(); | |
572 | } | |
573 | ||
34f43927 PZ |
574 | static inline u64 perf_event_clock(struct perf_event *event) |
575 | { | |
576 | return event->clock(); | |
577 | } | |
578 | ||
e5d1367f SE |
579 | #ifdef CONFIG_CGROUP_PERF |
580 | ||
e5d1367f SE |
581 | static inline bool |
582 | perf_cgroup_match(struct perf_event *event) | |
583 | { | |
584 | struct perf_event_context *ctx = event->ctx; | |
585 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
586 | ||
ef824fa1 TH |
587 | /* @event doesn't care about cgroup */ |
588 | if (!event->cgrp) | |
589 | return true; | |
590 | ||
591 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
592 | if (!cpuctx->cgrp) | |
593 | return false; | |
594 | ||
595 | /* | |
596 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
597 | * also enabled for all its descendant cgroups. If @cpuctx's | |
598 | * cgroup is a descendant of @event's (the test covers identity | |
599 | * case), it's a match. | |
600 | */ | |
601 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
602 | event->cgrp->css.cgroup); | |
e5d1367f SE |
603 | } |
604 | ||
e5d1367f SE |
605 | static inline void perf_detach_cgroup(struct perf_event *event) |
606 | { | |
4e2ba650 | 607 | css_put(&event->cgrp->css); |
e5d1367f SE |
608 | event->cgrp = NULL; |
609 | } | |
610 | ||
611 | static inline int is_cgroup_event(struct perf_event *event) | |
612 | { | |
613 | return event->cgrp != NULL; | |
614 | } | |
615 | ||
616 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
617 | { | |
618 | struct perf_cgroup_info *t; | |
619 | ||
620 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
621 | return t->time; | |
622 | } | |
623 | ||
624 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
625 | { | |
626 | struct perf_cgroup_info *info; | |
627 | u64 now; | |
628 | ||
629 | now = perf_clock(); | |
630 | ||
631 | info = this_cpu_ptr(cgrp->info); | |
632 | ||
633 | info->time += now - info->timestamp; | |
634 | info->timestamp = now; | |
635 | } | |
636 | ||
637 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
638 | { | |
639 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
640 | if (cgrp_out) | |
641 | __update_cgrp_time(cgrp_out); | |
642 | } | |
643 | ||
644 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
645 | { | |
3f7cce3c SE |
646 | struct perf_cgroup *cgrp; |
647 | ||
e5d1367f | 648 | /* |
3f7cce3c SE |
649 | * ensure we access cgroup data only when needed and |
650 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 651 | */ |
3f7cce3c | 652 | if (!is_cgroup_event(event)) |
e5d1367f SE |
653 | return; |
654 | ||
614e4c4e | 655 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
656 | /* |
657 | * Do not update time when cgroup is not active | |
658 | */ | |
659 | if (cgrp == event->cgrp) | |
660 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
661 | } |
662 | ||
663 | static inline void | |
3f7cce3c SE |
664 | perf_cgroup_set_timestamp(struct task_struct *task, |
665 | struct perf_event_context *ctx) | |
e5d1367f SE |
666 | { |
667 | struct perf_cgroup *cgrp; | |
668 | struct perf_cgroup_info *info; | |
669 | ||
3f7cce3c SE |
670 | /* |
671 | * ctx->lock held by caller | |
672 | * ensure we do not access cgroup data | |
673 | * unless we have the cgroup pinned (css_get) | |
674 | */ | |
675 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
676 | return; |
677 | ||
614e4c4e | 678 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 679 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 680 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
681 | } |
682 | ||
058fe1c0 DCC |
683 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
684 | ||
e5d1367f SE |
685 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
686 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
687 | ||
688 | /* | |
689 | * reschedule events based on the cgroup constraint of task. | |
690 | * | |
691 | * mode SWOUT : schedule out everything | |
692 | * mode SWIN : schedule in based on cgroup for next | |
693 | */ | |
18ab2cd3 | 694 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
695 | { |
696 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 697 | struct list_head *list; |
e5d1367f SE |
698 | unsigned long flags; |
699 | ||
700 | /* | |
058fe1c0 DCC |
701 | * Disable interrupts and preemption to avoid this CPU's |
702 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
703 | */ |
704 | local_irq_save(flags); | |
705 | ||
058fe1c0 DCC |
706 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
707 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
708 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 709 | |
058fe1c0 DCC |
710 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
711 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 712 | |
058fe1c0 DCC |
713 | if (mode & PERF_CGROUP_SWOUT) { |
714 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
715 | /* | |
716 | * must not be done before ctxswout due | |
717 | * to event_filter_match() in event_sched_out() | |
718 | */ | |
719 | cpuctx->cgrp = NULL; | |
720 | } | |
e5d1367f | 721 | |
058fe1c0 DCC |
722 | if (mode & PERF_CGROUP_SWIN) { |
723 | WARN_ON_ONCE(cpuctx->cgrp); | |
724 | /* | |
725 | * set cgrp before ctxsw in to allow | |
726 | * event_filter_match() to not have to pass | |
727 | * task around | |
728 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
729 | * because cgorup events are only per-cpu | |
730 | */ | |
731 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
732 | &cpuctx->ctx); | |
733 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 734 | } |
058fe1c0 DCC |
735 | perf_pmu_enable(cpuctx->ctx.pmu); |
736 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
737 | } |
738 | ||
e5d1367f SE |
739 | local_irq_restore(flags); |
740 | } | |
741 | ||
a8d757ef SE |
742 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
743 | struct task_struct *next) | |
e5d1367f | 744 | { |
a8d757ef SE |
745 | struct perf_cgroup *cgrp1; |
746 | struct perf_cgroup *cgrp2 = NULL; | |
747 | ||
ddaaf4e2 | 748 | rcu_read_lock(); |
a8d757ef SE |
749 | /* |
750 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
751 | * we do not need to pass the ctx here because we know |
752 | * we are holding the rcu lock | |
a8d757ef | 753 | */ |
614e4c4e | 754 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 755 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
756 | |
757 | /* | |
758 | * only schedule out current cgroup events if we know | |
759 | * that we are switching to a different cgroup. Otherwise, | |
760 | * do no touch the cgroup events. | |
761 | */ | |
762 | if (cgrp1 != cgrp2) | |
763 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
764 | |
765 | rcu_read_unlock(); | |
e5d1367f SE |
766 | } |
767 | ||
a8d757ef SE |
768 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
769 | struct task_struct *task) | |
e5d1367f | 770 | { |
a8d757ef SE |
771 | struct perf_cgroup *cgrp1; |
772 | struct perf_cgroup *cgrp2 = NULL; | |
773 | ||
ddaaf4e2 | 774 | rcu_read_lock(); |
a8d757ef SE |
775 | /* |
776 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
777 | * we do not need to pass the ctx here because we know |
778 | * we are holding the rcu lock | |
a8d757ef | 779 | */ |
614e4c4e | 780 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 781 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
782 | |
783 | /* | |
784 | * only need to schedule in cgroup events if we are changing | |
785 | * cgroup during ctxsw. Cgroup events were not scheduled | |
786 | * out of ctxsw out if that was not the case. | |
787 | */ | |
788 | if (cgrp1 != cgrp2) | |
789 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
790 | |
791 | rcu_read_unlock(); | |
e5d1367f SE |
792 | } |
793 | ||
794 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
795 | struct perf_event_attr *attr, | |
796 | struct perf_event *group_leader) | |
797 | { | |
798 | struct perf_cgroup *cgrp; | |
799 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
800 | struct fd f = fdget(fd); |
801 | int ret = 0; | |
e5d1367f | 802 | |
2903ff01 | 803 | if (!f.file) |
e5d1367f SE |
804 | return -EBADF; |
805 | ||
b583043e | 806 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 807 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
808 | if (IS_ERR(css)) { |
809 | ret = PTR_ERR(css); | |
810 | goto out; | |
811 | } | |
e5d1367f SE |
812 | |
813 | cgrp = container_of(css, struct perf_cgroup, css); | |
814 | event->cgrp = cgrp; | |
815 | ||
816 | /* | |
817 | * all events in a group must monitor | |
818 | * the same cgroup because a task belongs | |
819 | * to only one perf cgroup at a time | |
820 | */ | |
821 | if (group_leader && group_leader->cgrp != cgrp) { | |
822 | perf_detach_cgroup(event); | |
823 | ret = -EINVAL; | |
e5d1367f | 824 | } |
3db272c0 | 825 | out: |
2903ff01 | 826 | fdput(f); |
e5d1367f SE |
827 | return ret; |
828 | } | |
829 | ||
830 | static inline void | |
831 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
832 | { | |
833 | struct perf_cgroup_info *t; | |
834 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
835 | event->shadow_ctx_time = now - t->timestamp; | |
836 | } | |
837 | ||
838 | static inline void | |
839 | perf_cgroup_defer_enabled(struct perf_event *event) | |
840 | { | |
841 | /* | |
842 | * when the current task's perf cgroup does not match | |
843 | * the event's, we need to remember to call the | |
844 | * perf_mark_enable() function the first time a task with | |
845 | * a matching perf cgroup is scheduled in. | |
846 | */ | |
847 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
848 | event->cgrp_defer_enabled = 1; | |
849 | } | |
850 | ||
851 | static inline void | |
852 | perf_cgroup_mark_enabled(struct perf_event *event, | |
853 | struct perf_event_context *ctx) | |
854 | { | |
855 | struct perf_event *sub; | |
856 | u64 tstamp = perf_event_time(event); | |
857 | ||
858 | if (!event->cgrp_defer_enabled) | |
859 | return; | |
860 | ||
861 | event->cgrp_defer_enabled = 0; | |
862 | ||
863 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
864 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
865 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
866 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
867 | sub->cgrp_defer_enabled = 0; | |
868 | } | |
869 | } | |
870 | } | |
db4a8356 DCC |
871 | |
872 | /* | |
873 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
874 | * cleared when last cgroup event is removed. | |
875 | */ | |
876 | static inline void | |
877 | list_update_cgroup_event(struct perf_event *event, | |
878 | struct perf_event_context *ctx, bool add) | |
879 | { | |
880 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 881 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
882 | |
883 | if (!is_cgroup_event(event)) | |
884 | return; | |
885 | ||
886 | if (add && ctx->nr_cgroups++) | |
887 | return; | |
888 | else if (!add && --ctx->nr_cgroups) | |
889 | return; | |
890 | /* | |
891 | * Because cgroup events are always per-cpu events, | |
892 | * this will always be called from the right CPU. | |
893 | */ | |
894 | cpuctx = __get_cpu_context(ctx); | |
058fe1c0 DCC |
895 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; |
896 | /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/ | |
897 | if (add) { | |
898 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
899 | if (perf_cgroup_from_task(current, ctx) == event->cgrp) | |
900 | cpuctx->cgrp = event->cgrp; | |
901 | } else { | |
902 | list_del(cpuctx_entry); | |
8fc31ce8 | 903 | cpuctx->cgrp = NULL; |
058fe1c0 | 904 | } |
db4a8356 DCC |
905 | } |
906 | ||
e5d1367f SE |
907 | #else /* !CONFIG_CGROUP_PERF */ |
908 | ||
909 | static inline bool | |
910 | perf_cgroup_match(struct perf_event *event) | |
911 | { | |
912 | return true; | |
913 | } | |
914 | ||
915 | static inline void perf_detach_cgroup(struct perf_event *event) | |
916 | {} | |
917 | ||
918 | static inline int is_cgroup_event(struct perf_event *event) | |
919 | { | |
920 | return 0; | |
921 | } | |
922 | ||
923 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
924 | { | |
925 | return 0; | |
926 | } | |
927 | ||
928 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
929 | { | |
930 | } | |
931 | ||
932 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
933 | { | |
934 | } | |
935 | ||
a8d757ef SE |
936 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
937 | struct task_struct *next) | |
e5d1367f SE |
938 | { |
939 | } | |
940 | ||
a8d757ef SE |
941 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
942 | struct task_struct *task) | |
e5d1367f SE |
943 | { |
944 | } | |
945 | ||
946 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
947 | struct perf_event_attr *attr, | |
948 | struct perf_event *group_leader) | |
949 | { | |
950 | return -EINVAL; | |
951 | } | |
952 | ||
953 | static inline void | |
3f7cce3c SE |
954 | perf_cgroup_set_timestamp(struct task_struct *task, |
955 | struct perf_event_context *ctx) | |
e5d1367f SE |
956 | { |
957 | } | |
958 | ||
959 | void | |
960 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
961 | { | |
962 | } | |
963 | ||
964 | static inline void | |
965 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
966 | { | |
967 | } | |
968 | ||
969 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
970 | { | |
971 | return 0; | |
972 | } | |
973 | ||
974 | static inline void | |
975 | perf_cgroup_defer_enabled(struct perf_event *event) | |
976 | { | |
977 | } | |
978 | ||
979 | static inline void | |
980 | perf_cgroup_mark_enabled(struct perf_event *event, | |
981 | struct perf_event_context *ctx) | |
982 | { | |
983 | } | |
db4a8356 DCC |
984 | |
985 | static inline void | |
986 | list_update_cgroup_event(struct perf_event *event, | |
987 | struct perf_event_context *ctx, bool add) | |
988 | { | |
989 | } | |
990 | ||
e5d1367f SE |
991 | #endif |
992 | ||
9e630205 SE |
993 | /* |
994 | * set default to be dependent on timer tick just | |
995 | * like original code | |
996 | */ | |
997 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
998 | /* | |
999 | * function must be called with interrupts disbled | |
1000 | */ | |
272325c4 | 1001 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1002 | { |
1003 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1004 | int rotations = 0; |
1005 | ||
1006 | WARN_ON(!irqs_disabled()); | |
1007 | ||
1008 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1009 | rotations = perf_rotate_context(cpuctx); |
1010 | ||
4cfafd30 PZ |
1011 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1012 | if (rotations) | |
9e630205 | 1013 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1014 | else |
1015 | cpuctx->hrtimer_active = 0; | |
1016 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1017 | |
4cfafd30 | 1018 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1019 | } |
1020 | ||
272325c4 | 1021 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1022 | { |
272325c4 | 1023 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1024 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1025 | u64 interval; |
9e630205 SE |
1026 | |
1027 | /* no multiplexing needed for SW PMU */ | |
1028 | if (pmu->task_ctx_nr == perf_sw_context) | |
1029 | return; | |
1030 | ||
62b85639 SE |
1031 | /* |
1032 | * check default is sane, if not set then force to | |
1033 | * default interval (1/tick) | |
1034 | */ | |
272325c4 PZ |
1035 | interval = pmu->hrtimer_interval_ms; |
1036 | if (interval < 1) | |
1037 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1038 | |
272325c4 | 1039 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1040 | |
4cfafd30 PZ |
1041 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1042 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1043 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1044 | } |
1045 | ||
272325c4 | 1046 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1047 | { |
272325c4 | 1048 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1049 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1050 | unsigned long flags; |
9e630205 SE |
1051 | |
1052 | /* not for SW PMU */ | |
1053 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1054 | return 0; |
9e630205 | 1055 | |
4cfafd30 PZ |
1056 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1057 | if (!cpuctx->hrtimer_active) { | |
1058 | cpuctx->hrtimer_active = 1; | |
1059 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1060 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1061 | } | |
1062 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1063 | |
272325c4 | 1064 | return 0; |
9e630205 SE |
1065 | } |
1066 | ||
33696fc0 | 1067 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1068 | { |
33696fc0 PZ |
1069 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1070 | if (!(*count)++) | |
1071 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1072 | } |
9e35ad38 | 1073 | |
33696fc0 | 1074 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1075 | { |
33696fc0 PZ |
1076 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1077 | if (!--(*count)) | |
1078 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1079 | } |
9e35ad38 | 1080 | |
2fde4f94 | 1081 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1082 | |
1083 | /* | |
2fde4f94 MR |
1084 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1085 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1086 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1087 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1088 | */ |
2fde4f94 | 1089 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1090 | { |
2fde4f94 | 1091 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1092 | |
e9d2b064 | 1093 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1094 | |
2fde4f94 MR |
1095 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1096 | ||
1097 | list_add(&ctx->active_ctx_list, head); | |
1098 | } | |
1099 | ||
1100 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1101 | { | |
1102 | WARN_ON(!irqs_disabled()); | |
1103 | ||
1104 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1105 | ||
1106 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1107 | } |
9e35ad38 | 1108 | |
cdd6c482 | 1109 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1110 | { |
e5289d4a | 1111 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1112 | } |
1113 | ||
4af57ef2 YZ |
1114 | static void free_ctx(struct rcu_head *head) |
1115 | { | |
1116 | struct perf_event_context *ctx; | |
1117 | ||
1118 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1119 | kfree(ctx->task_ctx_data); | |
1120 | kfree(ctx); | |
1121 | } | |
1122 | ||
cdd6c482 | 1123 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1124 | { |
564c2b21 PM |
1125 | if (atomic_dec_and_test(&ctx->refcount)) { |
1126 | if (ctx->parent_ctx) | |
1127 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1128 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1129 | put_task_struct(ctx->task); |
4af57ef2 | 1130 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1131 | } |
a63eaf34 PM |
1132 | } |
1133 | ||
f63a8daa PZ |
1134 | /* |
1135 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1136 | * perf_pmu_migrate_context() we need some magic. | |
1137 | * | |
1138 | * Those places that change perf_event::ctx will hold both | |
1139 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1140 | * | |
8b10c5e2 PZ |
1141 | * Lock ordering is by mutex address. There are two other sites where |
1142 | * perf_event_context::mutex nests and those are: | |
1143 | * | |
1144 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1145 | * perf_event_exit_event() |
1146 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1147 | * |
1148 | * - perf_event_init_context() [ parent, 0 ] | |
1149 | * inherit_task_group() | |
1150 | * inherit_group() | |
1151 | * inherit_event() | |
1152 | * perf_event_alloc() | |
1153 | * perf_init_event() | |
1154 | * perf_try_init_event() [ child , 1 ] | |
1155 | * | |
1156 | * While it appears there is an obvious deadlock here -- the parent and child | |
1157 | * nesting levels are inverted between the two. This is in fact safe because | |
1158 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1159 | * spawning task cannot (yet) exit. | |
1160 | * | |
1161 | * But remember that that these are parent<->child context relations, and | |
1162 | * migration does not affect children, therefore these two orderings should not | |
1163 | * interact. | |
f63a8daa PZ |
1164 | * |
1165 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1166 | * because the sys_perf_event_open() case will install a new event and break | |
1167 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1168 | * concerned with cpuctx and that doesn't have children. | |
1169 | * | |
1170 | * The places that change perf_event::ctx will issue: | |
1171 | * | |
1172 | * perf_remove_from_context(); | |
1173 | * synchronize_rcu(); | |
1174 | * perf_install_in_context(); | |
1175 | * | |
1176 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1177 | * quiesce the event, after which we can install it in the new location. This | |
1178 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1179 | * while in transit. Therefore all such accessors should also acquire | |
1180 | * perf_event_context::mutex to serialize against this. | |
1181 | * | |
1182 | * However; because event->ctx can change while we're waiting to acquire | |
1183 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1184 | * function. | |
1185 | * | |
1186 | * Lock order: | |
79c9ce57 | 1187 | * cred_guard_mutex |
f63a8daa PZ |
1188 | * task_struct::perf_event_mutex |
1189 | * perf_event_context::mutex | |
f63a8daa | 1190 | * perf_event::child_mutex; |
07c4a776 | 1191 | * perf_event_context::lock |
f63a8daa PZ |
1192 | * perf_event::mmap_mutex |
1193 | * mmap_sem | |
1194 | */ | |
a83fe28e PZ |
1195 | static struct perf_event_context * |
1196 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1197 | { |
1198 | struct perf_event_context *ctx; | |
1199 | ||
1200 | again: | |
1201 | rcu_read_lock(); | |
1202 | ctx = ACCESS_ONCE(event->ctx); | |
1203 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1204 | rcu_read_unlock(); | |
1205 | goto again; | |
1206 | } | |
1207 | rcu_read_unlock(); | |
1208 | ||
a83fe28e | 1209 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1210 | if (event->ctx != ctx) { |
1211 | mutex_unlock(&ctx->mutex); | |
1212 | put_ctx(ctx); | |
1213 | goto again; | |
1214 | } | |
1215 | ||
1216 | return ctx; | |
1217 | } | |
1218 | ||
a83fe28e PZ |
1219 | static inline struct perf_event_context * |
1220 | perf_event_ctx_lock(struct perf_event *event) | |
1221 | { | |
1222 | return perf_event_ctx_lock_nested(event, 0); | |
1223 | } | |
1224 | ||
f63a8daa PZ |
1225 | static void perf_event_ctx_unlock(struct perf_event *event, |
1226 | struct perf_event_context *ctx) | |
1227 | { | |
1228 | mutex_unlock(&ctx->mutex); | |
1229 | put_ctx(ctx); | |
1230 | } | |
1231 | ||
211de6eb PZ |
1232 | /* |
1233 | * This must be done under the ctx->lock, such as to serialize against | |
1234 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1235 | * calling scheduler related locks and ctx->lock nests inside those. | |
1236 | */ | |
1237 | static __must_check struct perf_event_context * | |
1238 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1239 | { |
211de6eb PZ |
1240 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1241 | ||
1242 | lockdep_assert_held(&ctx->lock); | |
1243 | ||
1244 | if (parent_ctx) | |
71a851b4 | 1245 | ctx->parent_ctx = NULL; |
5a3126d4 | 1246 | ctx->generation++; |
211de6eb PZ |
1247 | |
1248 | return parent_ctx; | |
71a851b4 PZ |
1249 | } |
1250 | ||
6844c09d ACM |
1251 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1252 | { | |
1253 | /* | |
1254 | * only top level events have the pid namespace they were created in | |
1255 | */ | |
1256 | if (event->parent) | |
1257 | event = event->parent; | |
1258 | ||
1259 | return task_tgid_nr_ns(p, event->ns); | |
1260 | } | |
1261 | ||
1262 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1263 | { | |
1264 | /* | |
1265 | * only top level events have the pid namespace they were created in | |
1266 | */ | |
1267 | if (event->parent) | |
1268 | event = event->parent; | |
1269 | ||
1270 | return task_pid_nr_ns(p, event->ns); | |
1271 | } | |
1272 | ||
7f453c24 | 1273 | /* |
cdd6c482 | 1274 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1275 | * to userspace. |
1276 | */ | |
cdd6c482 | 1277 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1278 | { |
cdd6c482 | 1279 | u64 id = event->id; |
7f453c24 | 1280 | |
cdd6c482 IM |
1281 | if (event->parent) |
1282 | id = event->parent->id; | |
7f453c24 PZ |
1283 | |
1284 | return id; | |
1285 | } | |
1286 | ||
25346b93 | 1287 | /* |
cdd6c482 | 1288 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1289 | * |
25346b93 PM |
1290 | * This has to cope with with the fact that until it is locked, |
1291 | * the context could get moved to another task. | |
1292 | */ | |
cdd6c482 | 1293 | static struct perf_event_context * |
8dc85d54 | 1294 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1295 | { |
cdd6c482 | 1296 | struct perf_event_context *ctx; |
25346b93 | 1297 | |
9ed6060d | 1298 | retry: |
058ebd0e PZ |
1299 | /* |
1300 | * One of the few rules of preemptible RCU is that one cannot do | |
1301 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1302 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1303 | * rcu_read_unlock_special(). |
1304 | * | |
1305 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1306 | * side critical section has interrupts disabled. |
058ebd0e | 1307 | */ |
2fd59077 | 1308 | local_irq_save(*flags); |
058ebd0e | 1309 | rcu_read_lock(); |
8dc85d54 | 1310 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1311 | if (ctx) { |
1312 | /* | |
1313 | * If this context is a clone of another, it might | |
1314 | * get swapped for another underneath us by | |
cdd6c482 | 1315 | * perf_event_task_sched_out, though the |
25346b93 PM |
1316 | * rcu_read_lock() protects us from any context |
1317 | * getting freed. Lock the context and check if it | |
1318 | * got swapped before we could get the lock, and retry | |
1319 | * if so. If we locked the right context, then it | |
1320 | * can't get swapped on us any more. | |
1321 | */ | |
2fd59077 | 1322 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1323 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1324 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1325 | rcu_read_unlock(); |
2fd59077 | 1326 | local_irq_restore(*flags); |
25346b93 PM |
1327 | goto retry; |
1328 | } | |
b49a9e7e | 1329 | |
63b6da39 PZ |
1330 | if (ctx->task == TASK_TOMBSTONE || |
1331 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1332 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1333 | ctx = NULL; |
828b6f0e PZ |
1334 | } else { |
1335 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1336 | } |
25346b93 PM |
1337 | } |
1338 | rcu_read_unlock(); | |
2fd59077 PM |
1339 | if (!ctx) |
1340 | local_irq_restore(*flags); | |
25346b93 PM |
1341 | return ctx; |
1342 | } | |
1343 | ||
1344 | /* | |
1345 | * Get the context for a task and increment its pin_count so it | |
1346 | * can't get swapped to another task. This also increments its | |
1347 | * reference count so that the context can't get freed. | |
1348 | */ | |
8dc85d54 PZ |
1349 | static struct perf_event_context * |
1350 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1351 | { |
cdd6c482 | 1352 | struct perf_event_context *ctx; |
25346b93 PM |
1353 | unsigned long flags; |
1354 | ||
8dc85d54 | 1355 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1356 | if (ctx) { |
1357 | ++ctx->pin_count; | |
e625cce1 | 1358 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1359 | } |
1360 | return ctx; | |
1361 | } | |
1362 | ||
cdd6c482 | 1363 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1364 | { |
1365 | unsigned long flags; | |
1366 | ||
e625cce1 | 1367 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1368 | --ctx->pin_count; |
e625cce1 | 1369 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1370 | } |
1371 | ||
f67218c3 PZ |
1372 | /* |
1373 | * Update the record of the current time in a context. | |
1374 | */ | |
1375 | static void update_context_time(struct perf_event_context *ctx) | |
1376 | { | |
1377 | u64 now = perf_clock(); | |
1378 | ||
1379 | ctx->time += now - ctx->timestamp; | |
1380 | ctx->timestamp = now; | |
1381 | } | |
1382 | ||
4158755d SE |
1383 | static u64 perf_event_time(struct perf_event *event) |
1384 | { | |
1385 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1386 | |
1387 | if (is_cgroup_event(event)) | |
1388 | return perf_cgroup_event_time(event); | |
1389 | ||
4158755d SE |
1390 | return ctx ? ctx->time : 0; |
1391 | } | |
1392 | ||
f67218c3 PZ |
1393 | /* |
1394 | * Update the total_time_enabled and total_time_running fields for a event. | |
1395 | */ | |
1396 | static void update_event_times(struct perf_event *event) | |
1397 | { | |
1398 | struct perf_event_context *ctx = event->ctx; | |
1399 | u64 run_end; | |
1400 | ||
3cbaa590 PZ |
1401 | lockdep_assert_held(&ctx->lock); |
1402 | ||
f67218c3 PZ |
1403 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1404 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1405 | return; | |
3cbaa590 | 1406 | |
e5d1367f SE |
1407 | /* |
1408 | * in cgroup mode, time_enabled represents | |
1409 | * the time the event was enabled AND active | |
1410 | * tasks were in the monitored cgroup. This is | |
1411 | * independent of the activity of the context as | |
1412 | * there may be a mix of cgroup and non-cgroup events. | |
1413 | * | |
1414 | * That is why we treat cgroup events differently | |
1415 | * here. | |
1416 | */ | |
1417 | if (is_cgroup_event(event)) | |
46cd6a7f | 1418 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1419 | else if (ctx->is_active) |
1420 | run_end = ctx->time; | |
acd1d7c1 PZ |
1421 | else |
1422 | run_end = event->tstamp_stopped; | |
1423 | ||
1424 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1425 | |
1426 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1427 | run_end = event->tstamp_stopped; | |
1428 | else | |
4158755d | 1429 | run_end = perf_event_time(event); |
f67218c3 PZ |
1430 | |
1431 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1432 | |
f67218c3 PZ |
1433 | } |
1434 | ||
96c21a46 PZ |
1435 | /* |
1436 | * Update total_time_enabled and total_time_running for all events in a group. | |
1437 | */ | |
1438 | static void update_group_times(struct perf_event *leader) | |
1439 | { | |
1440 | struct perf_event *event; | |
1441 | ||
1442 | update_event_times(leader); | |
1443 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1444 | update_event_times(event); | |
1445 | } | |
1446 | ||
487f05e1 AS |
1447 | static enum event_type_t get_event_type(struct perf_event *event) |
1448 | { | |
1449 | struct perf_event_context *ctx = event->ctx; | |
1450 | enum event_type_t event_type; | |
1451 | ||
1452 | lockdep_assert_held(&ctx->lock); | |
1453 | ||
1454 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; | |
1455 | if (!ctx->task) | |
1456 | event_type |= EVENT_CPU; | |
1457 | ||
1458 | return event_type; | |
1459 | } | |
1460 | ||
889ff015 FW |
1461 | static struct list_head * |
1462 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1463 | { | |
1464 | if (event->attr.pinned) | |
1465 | return &ctx->pinned_groups; | |
1466 | else | |
1467 | return &ctx->flexible_groups; | |
1468 | } | |
1469 | ||
fccc714b | 1470 | /* |
cdd6c482 | 1471 | * Add a event from the lists for its context. |
fccc714b PZ |
1472 | * Must be called with ctx->mutex and ctx->lock held. |
1473 | */ | |
04289bb9 | 1474 | static void |
cdd6c482 | 1475 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1476 | { |
c994d613 PZ |
1477 | lockdep_assert_held(&ctx->lock); |
1478 | ||
8a49542c PZ |
1479 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1480 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1481 | |
1482 | /* | |
8a49542c PZ |
1483 | * If we're a stand alone event or group leader, we go to the context |
1484 | * list, group events are kept attached to the group so that | |
1485 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1486 | */ |
8a49542c | 1487 | if (event->group_leader == event) { |
889ff015 FW |
1488 | struct list_head *list; |
1489 | ||
4ff6a8de | 1490 | event->group_caps = event->event_caps; |
d6f962b5 | 1491 | |
889ff015 FW |
1492 | list = ctx_group_list(event, ctx); |
1493 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1494 | } |
592903cd | 1495 | |
db4a8356 | 1496 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1497 | |
cdd6c482 IM |
1498 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1499 | ctx->nr_events++; | |
1500 | if (event->attr.inherit_stat) | |
bfbd3381 | 1501 | ctx->nr_stat++; |
5a3126d4 PZ |
1502 | |
1503 | ctx->generation++; | |
04289bb9 IM |
1504 | } |
1505 | ||
0231bb53 JO |
1506 | /* |
1507 | * Initialize event state based on the perf_event_attr::disabled. | |
1508 | */ | |
1509 | static inline void perf_event__state_init(struct perf_event *event) | |
1510 | { | |
1511 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1512 | PERF_EVENT_STATE_INACTIVE; | |
1513 | } | |
1514 | ||
a723968c | 1515 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1516 | { |
1517 | int entry = sizeof(u64); /* value */ | |
1518 | int size = 0; | |
1519 | int nr = 1; | |
1520 | ||
1521 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1522 | size += sizeof(u64); | |
1523 | ||
1524 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1525 | size += sizeof(u64); | |
1526 | ||
1527 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1528 | entry += sizeof(u64); | |
1529 | ||
1530 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1531 | nr += nr_siblings; |
c320c7b7 ACM |
1532 | size += sizeof(u64); |
1533 | } | |
1534 | ||
1535 | size += entry * nr; | |
1536 | event->read_size = size; | |
1537 | } | |
1538 | ||
a723968c | 1539 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1540 | { |
1541 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1542 | u16 size = 0; |
1543 | ||
c320c7b7 ACM |
1544 | if (sample_type & PERF_SAMPLE_IP) |
1545 | size += sizeof(data->ip); | |
1546 | ||
6844c09d ACM |
1547 | if (sample_type & PERF_SAMPLE_ADDR) |
1548 | size += sizeof(data->addr); | |
1549 | ||
1550 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1551 | size += sizeof(data->period); | |
1552 | ||
c3feedf2 AK |
1553 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1554 | size += sizeof(data->weight); | |
1555 | ||
6844c09d ACM |
1556 | if (sample_type & PERF_SAMPLE_READ) |
1557 | size += event->read_size; | |
1558 | ||
d6be9ad6 SE |
1559 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1560 | size += sizeof(data->data_src.val); | |
1561 | ||
fdfbbd07 AK |
1562 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1563 | size += sizeof(data->txn); | |
1564 | ||
6844c09d ACM |
1565 | event->header_size = size; |
1566 | } | |
1567 | ||
a723968c PZ |
1568 | /* |
1569 | * Called at perf_event creation and when events are attached/detached from a | |
1570 | * group. | |
1571 | */ | |
1572 | static void perf_event__header_size(struct perf_event *event) | |
1573 | { | |
1574 | __perf_event_read_size(event, | |
1575 | event->group_leader->nr_siblings); | |
1576 | __perf_event_header_size(event, event->attr.sample_type); | |
1577 | } | |
1578 | ||
6844c09d ACM |
1579 | static void perf_event__id_header_size(struct perf_event *event) |
1580 | { | |
1581 | struct perf_sample_data *data; | |
1582 | u64 sample_type = event->attr.sample_type; | |
1583 | u16 size = 0; | |
1584 | ||
c320c7b7 ACM |
1585 | if (sample_type & PERF_SAMPLE_TID) |
1586 | size += sizeof(data->tid_entry); | |
1587 | ||
1588 | if (sample_type & PERF_SAMPLE_TIME) | |
1589 | size += sizeof(data->time); | |
1590 | ||
ff3d527c AH |
1591 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1592 | size += sizeof(data->id); | |
1593 | ||
c320c7b7 ACM |
1594 | if (sample_type & PERF_SAMPLE_ID) |
1595 | size += sizeof(data->id); | |
1596 | ||
1597 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1598 | size += sizeof(data->stream_id); | |
1599 | ||
1600 | if (sample_type & PERF_SAMPLE_CPU) | |
1601 | size += sizeof(data->cpu_entry); | |
1602 | ||
6844c09d | 1603 | event->id_header_size = size; |
c320c7b7 ACM |
1604 | } |
1605 | ||
a723968c PZ |
1606 | static bool perf_event_validate_size(struct perf_event *event) |
1607 | { | |
1608 | /* | |
1609 | * The values computed here will be over-written when we actually | |
1610 | * attach the event. | |
1611 | */ | |
1612 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1613 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1614 | perf_event__id_header_size(event); | |
1615 | ||
1616 | /* | |
1617 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1618 | * Conservative limit to allow for callchains and other variable fields. | |
1619 | */ | |
1620 | if (event->read_size + event->header_size + | |
1621 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1622 | return false; | |
1623 | ||
1624 | return true; | |
1625 | } | |
1626 | ||
8a49542c PZ |
1627 | static void perf_group_attach(struct perf_event *event) |
1628 | { | |
c320c7b7 | 1629 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1630 | |
a76a82a3 PZ |
1631 | lockdep_assert_held(&event->ctx->lock); |
1632 | ||
74c3337c PZ |
1633 | /* |
1634 | * We can have double attach due to group movement in perf_event_open. | |
1635 | */ | |
1636 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1637 | return; | |
1638 | ||
8a49542c PZ |
1639 | event->attach_state |= PERF_ATTACH_GROUP; |
1640 | ||
1641 | if (group_leader == event) | |
1642 | return; | |
1643 | ||
652884fe PZ |
1644 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1645 | ||
4ff6a8de | 1646 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1647 | |
1648 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1649 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1650 | |
1651 | perf_event__header_size(group_leader); | |
1652 | ||
1653 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1654 | perf_event__header_size(pos); | |
8a49542c PZ |
1655 | } |
1656 | ||
a63eaf34 | 1657 | /* |
cdd6c482 | 1658 | * Remove a event from the lists for its context. |
fccc714b | 1659 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1660 | */ |
04289bb9 | 1661 | static void |
cdd6c482 | 1662 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1663 | { |
652884fe PZ |
1664 | WARN_ON_ONCE(event->ctx != ctx); |
1665 | lockdep_assert_held(&ctx->lock); | |
1666 | ||
8a49542c PZ |
1667 | /* |
1668 | * We can have double detach due to exit/hot-unplug + close. | |
1669 | */ | |
1670 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1671 | return; |
8a49542c PZ |
1672 | |
1673 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1674 | ||
db4a8356 | 1675 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1676 | |
cdd6c482 IM |
1677 | ctx->nr_events--; |
1678 | if (event->attr.inherit_stat) | |
bfbd3381 | 1679 | ctx->nr_stat--; |
8bc20959 | 1680 | |
cdd6c482 | 1681 | list_del_rcu(&event->event_entry); |
04289bb9 | 1682 | |
8a49542c PZ |
1683 | if (event->group_leader == event) |
1684 | list_del_init(&event->group_entry); | |
5c148194 | 1685 | |
96c21a46 | 1686 | update_group_times(event); |
b2e74a26 SE |
1687 | |
1688 | /* | |
1689 | * If event was in error state, then keep it | |
1690 | * that way, otherwise bogus counts will be | |
1691 | * returned on read(). The only way to get out | |
1692 | * of error state is by explicit re-enabling | |
1693 | * of the event | |
1694 | */ | |
1695 | if (event->state > PERF_EVENT_STATE_OFF) | |
1696 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1697 | |
1698 | ctx->generation++; | |
050735b0 PZ |
1699 | } |
1700 | ||
8a49542c | 1701 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1702 | { |
1703 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1704 | struct list_head *list = NULL; |
1705 | ||
a76a82a3 PZ |
1706 | lockdep_assert_held(&event->ctx->lock); |
1707 | ||
8a49542c PZ |
1708 | /* |
1709 | * We can have double detach due to exit/hot-unplug + close. | |
1710 | */ | |
1711 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1712 | return; | |
1713 | ||
1714 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1715 | ||
1716 | /* | |
1717 | * If this is a sibling, remove it from its group. | |
1718 | */ | |
1719 | if (event->group_leader != event) { | |
1720 | list_del_init(&event->group_entry); | |
1721 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1722 | goto out; |
8a49542c PZ |
1723 | } |
1724 | ||
1725 | if (!list_empty(&event->group_entry)) | |
1726 | list = &event->group_entry; | |
2e2af50b | 1727 | |
04289bb9 | 1728 | /* |
cdd6c482 IM |
1729 | * If this was a group event with sibling events then |
1730 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1731 | * to whatever list we are on. |
04289bb9 | 1732 | */ |
cdd6c482 | 1733 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1734 | if (list) |
1735 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1736 | sibling->group_leader = sibling; |
d6f962b5 FW |
1737 | |
1738 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1739 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1740 | |
1741 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1742 | } |
c320c7b7 ACM |
1743 | |
1744 | out: | |
1745 | perf_event__header_size(event->group_leader); | |
1746 | ||
1747 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1748 | perf_event__header_size(tmp); | |
04289bb9 IM |
1749 | } |
1750 | ||
fadfe7be JO |
1751 | static bool is_orphaned_event(struct perf_event *event) |
1752 | { | |
a69b0ca4 | 1753 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1754 | } |
1755 | ||
2c81a647 | 1756 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1757 | { |
1758 | struct pmu *pmu = event->pmu; | |
1759 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1760 | } | |
1761 | ||
2c81a647 MR |
1762 | /* |
1763 | * Check whether we should attempt to schedule an event group based on | |
1764 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1765 | * potentially with a SW leader, so we must check all the filters, to | |
1766 | * determine whether a group is schedulable: | |
1767 | */ | |
1768 | static inline int pmu_filter_match(struct perf_event *event) | |
1769 | { | |
1770 | struct perf_event *child; | |
1771 | ||
1772 | if (!__pmu_filter_match(event)) | |
1773 | return 0; | |
1774 | ||
1775 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1776 | if (!__pmu_filter_match(child)) | |
1777 | return 0; | |
1778 | } | |
1779 | ||
1780 | return 1; | |
1781 | } | |
1782 | ||
fa66f07a SE |
1783 | static inline int |
1784 | event_filter_match(struct perf_event *event) | |
1785 | { | |
0b8f1e2e PZ |
1786 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1787 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1788 | } |
1789 | ||
9ffcfa6f SE |
1790 | static void |
1791 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1792 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1793 | struct perf_event_context *ctx) |
3b6f9e5c | 1794 | { |
4158755d | 1795 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1796 | u64 delta; |
652884fe PZ |
1797 | |
1798 | WARN_ON_ONCE(event->ctx != ctx); | |
1799 | lockdep_assert_held(&ctx->lock); | |
1800 | ||
fa66f07a SE |
1801 | /* |
1802 | * An event which could not be activated because of | |
1803 | * filter mismatch still needs to have its timings | |
1804 | * maintained, otherwise bogus information is return | |
1805 | * via read() for time_enabled, time_running: | |
1806 | */ | |
0b8f1e2e PZ |
1807 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1808 | !event_filter_match(event)) { | |
e5d1367f | 1809 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1810 | event->tstamp_running += delta; |
4158755d | 1811 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1812 | } |
1813 | ||
cdd6c482 | 1814 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1815 | return; |
3b6f9e5c | 1816 | |
44377277 AS |
1817 | perf_pmu_disable(event->pmu); |
1818 | ||
28a967c3 PZ |
1819 | event->tstamp_stopped = tstamp; |
1820 | event->pmu->del(event, 0); | |
1821 | event->oncpu = -1; | |
cdd6c482 IM |
1822 | event->state = PERF_EVENT_STATE_INACTIVE; |
1823 | if (event->pending_disable) { | |
1824 | event->pending_disable = 0; | |
1825 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1826 | } |
3b6f9e5c | 1827 | |
cdd6c482 | 1828 | if (!is_software_event(event)) |
3b6f9e5c | 1829 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1830 | if (!--ctx->nr_active) |
1831 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1832 | if (event->attr.freq && event->attr.sample_freq) |
1833 | ctx->nr_freq--; | |
cdd6c482 | 1834 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1835 | cpuctx->exclusive = 0; |
44377277 AS |
1836 | |
1837 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1838 | } |
1839 | ||
d859e29f | 1840 | static void |
cdd6c482 | 1841 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1842 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1843 | struct perf_event_context *ctx) |
d859e29f | 1844 | { |
cdd6c482 | 1845 | struct perf_event *event; |
fa66f07a | 1846 | int state = group_event->state; |
d859e29f | 1847 | |
3f005e7d MR |
1848 | perf_pmu_disable(ctx->pmu); |
1849 | ||
cdd6c482 | 1850 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1851 | |
1852 | /* | |
1853 | * Schedule out siblings (if any): | |
1854 | */ | |
cdd6c482 IM |
1855 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1856 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1857 | |
3f005e7d MR |
1858 | perf_pmu_enable(ctx->pmu); |
1859 | ||
fa66f07a | 1860 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1861 | cpuctx->exclusive = 0; |
1862 | } | |
1863 | ||
45a0e07a | 1864 | #define DETACH_GROUP 0x01UL |
0017960f | 1865 | |
0793a61d | 1866 | /* |
cdd6c482 | 1867 | * Cross CPU call to remove a performance event |
0793a61d | 1868 | * |
cdd6c482 | 1869 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1870 | * remove it from the context list. |
1871 | */ | |
fae3fde6 PZ |
1872 | static void |
1873 | __perf_remove_from_context(struct perf_event *event, | |
1874 | struct perf_cpu_context *cpuctx, | |
1875 | struct perf_event_context *ctx, | |
1876 | void *info) | |
0793a61d | 1877 | { |
45a0e07a | 1878 | unsigned long flags = (unsigned long)info; |
0793a61d | 1879 | |
cdd6c482 | 1880 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1881 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1882 | perf_group_detach(event); |
cdd6c482 | 1883 | list_del_event(event, ctx); |
39a43640 PZ |
1884 | |
1885 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1886 | ctx->is_active = 0; |
39a43640 PZ |
1887 | if (ctx->task) { |
1888 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1889 | cpuctx->task_ctx = NULL; | |
1890 | } | |
64ce3126 | 1891 | } |
0793a61d TG |
1892 | } |
1893 | ||
0793a61d | 1894 | /* |
cdd6c482 | 1895 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1896 | * |
cdd6c482 IM |
1897 | * If event->ctx is a cloned context, callers must make sure that |
1898 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1899 | * remains valid. This is OK when called from perf_release since |
1900 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1901 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1902 | * context has been detached from its task. |
0793a61d | 1903 | */ |
45a0e07a | 1904 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1905 | { |
a76a82a3 PZ |
1906 | struct perf_event_context *ctx = event->ctx; |
1907 | ||
1908 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 1909 | |
45a0e07a | 1910 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
1911 | |
1912 | /* | |
1913 | * The above event_function_call() can NO-OP when it hits | |
1914 | * TASK_TOMBSTONE. In that case we must already have been detached | |
1915 | * from the context (by perf_event_exit_event()) but the grouping | |
1916 | * might still be in-tact. | |
1917 | */ | |
1918 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
1919 | if ((flags & DETACH_GROUP) && | |
1920 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
1921 | /* | |
1922 | * Since in that case we cannot possibly be scheduled, simply | |
1923 | * detach now. | |
1924 | */ | |
1925 | raw_spin_lock_irq(&ctx->lock); | |
1926 | perf_group_detach(event); | |
1927 | raw_spin_unlock_irq(&ctx->lock); | |
1928 | } | |
0793a61d TG |
1929 | } |
1930 | ||
d859e29f | 1931 | /* |
cdd6c482 | 1932 | * Cross CPU call to disable a performance event |
d859e29f | 1933 | */ |
fae3fde6 PZ |
1934 | static void __perf_event_disable(struct perf_event *event, |
1935 | struct perf_cpu_context *cpuctx, | |
1936 | struct perf_event_context *ctx, | |
1937 | void *info) | |
7b648018 | 1938 | { |
fae3fde6 PZ |
1939 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1940 | return; | |
7b648018 | 1941 | |
fae3fde6 PZ |
1942 | update_context_time(ctx); |
1943 | update_cgrp_time_from_event(event); | |
1944 | update_group_times(event); | |
1945 | if (event == event->group_leader) | |
1946 | group_sched_out(event, cpuctx, ctx); | |
1947 | else | |
1948 | event_sched_out(event, cpuctx, ctx); | |
1949 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1950 | } |
1951 | ||
d859e29f | 1952 | /* |
cdd6c482 | 1953 | * Disable a event. |
c93f7669 | 1954 | * |
cdd6c482 IM |
1955 | * If event->ctx is a cloned context, callers must make sure that |
1956 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1957 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1958 | * perf_event_for_each_child or perf_event_for_each because they |
1959 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1960 | * goes to exit will block in perf_event_exit_event(). |
1961 | * | |
cdd6c482 | 1962 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1963 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1964 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1965 | */ |
f63a8daa | 1966 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1967 | { |
cdd6c482 | 1968 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1969 | |
e625cce1 | 1970 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1971 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1972 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1973 | return; |
53cfbf59 | 1974 | } |
e625cce1 | 1975 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1976 | |
fae3fde6 PZ |
1977 | event_function_call(event, __perf_event_disable, NULL); |
1978 | } | |
1979 | ||
1980 | void perf_event_disable_local(struct perf_event *event) | |
1981 | { | |
1982 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1983 | } |
f63a8daa PZ |
1984 | |
1985 | /* | |
1986 | * Strictly speaking kernel users cannot create groups and therefore this | |
1987 | * interface does not need the perf_event_ctx_lock() magic. | |
1988 | */ | |
1989 | void perf_event_disable(struct perf_event *event) | |
1990 | { | |
1991 | struct perf_event_context *ctx; | |
1992 | ||
1993 | ctx = perf_event_ctx_lock(event); | |
1994 | _perf_event_disable(event); | |
1995 | perf_event_ctx_unlock(event, ctx); | |
1996 | } | |
dcfce4a0 | 1997 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1998 | |
5aab90ce JO |
1999 | void perf_event_disable_inatomic(struct perf_event *event) |
2000 | { | |
2001 | event->pending_disable = 1; | |
2002 | irq_work_queue(&event->pending); | |
2003 | } | |
2004 | ||
e5d1367f SE |
2005 | static void perf_set_shadow_time(struct perf_event *event, |
2006 | struct perf_event_context *ctx, | |
2007 | u64 tstamp) | |
2008 | { | |
2009 | /* | |
2010 | * use the correct time source for the time snapshot | |
2011 | * | |
2012 | * We could get by without this by leveraging the | |
2013 | * fact that to get to this function, the caller | |
2014 | * has most likely already called update_context_time() | |
2015 | * and update_cgrp_time_xx() and thus both timestamp | |
2016 | * are identical (or very close). Given that tstamp is, | |
2017 | * already adjusted for cgroup, we could say that: | |
2018 | * tstamp - ctx->timestamp | |
2019 | * is equivalent to | |
2020 | * tstamp - cgrp->timestamp. | |
2021 | * | |
2022 | * Then, in perf_output_read(), the calculation would | |
2023 | * work with no changes because: | |
2024 | * - event is guaranteed scheduled in | |
2025 | * - no scheduled out in between | |
2026 | * - thus the timestamp would be the same | |
2027 | * | |
2028 | * But this is a bit hairy. | |
2029 | * | |
2030 | * So instead, we have an explicit cgroup call to remain | |
2031 | * within the time time source all along. We believe it | |
2032 | * is cleaner and simpler to understand. | |
2033 | */ | |
2034 | if (is_cgroup_event(event)) | |
2035 | perf_cgroup_set_shadow_time(event, tstamp); | |
2036 | else | |
2037 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
2038 | } | |
2039 | ||
4fe757dd PZ |
2040 | #define MAX_INTERRUPTS (~0ULL) |
2041 | ||
2042 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2043 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2044 | |
235c7fc7 | 2045 | static int |
9ffcfa6f | 2046 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2047 | struct perf_cpu_context *cpuctx, |
6e37738a | 2048 | struct perf_event_context *ctx) |
235c7fc7 | 2049 | { |
4158755d | 2050 | u64 tstamp = perf_event_time(event); |
44377277 | 2051 | int ret = 0; |
4158755d | 2052 | |
63342411 PZ |
2053 | lockdep_assert_held(&ctx->lock); |
2054 | ||
cdd6c482 | 2055 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2056 | return 0; |
2057 | ||
95ff4ca2 AS |
2058 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2059 | /* | |
2060 | * Order event::oncpu write to happen before the ACTIVE state | |
2061 | * is visible. | |
2062 | */ | |
2063 | smp_wmb(); | |
2064 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
2065 | |
2066 | /* | |
2067 | * Unthrottle events, since we scheduled we might have missed several | |
2068 | * ticks already, also for a heavily scheduling task there is little | |
2069 | * guarantee it'll get a tick in a timely manner. | |
2070 | */ | |
2071 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2072 | perf_log_throttle(event, 1); | |
2073 | event->hw.interrupts = 0; | |
2074 | } | |
2075 | ||
235c7fc7 IM |
2076 | /* |
2077 | * The new state must be visible before we turn it on in the hardware: | |
2078 | */ | |
2079 | smp_wmb(); | |
2080 | ||
44377277 AS |
2081 | perf_pmu_disable(event->pmu); |
2082 | ||
72f669c0 SL |
2083 | perf_set_shadow_time(event, ctx, tstamp); |
2084 | ||
ec0d7729 AS |
2085 | perf_log_itrace_start(event); |
2086 | ||
a4eaf7f1 | 2087 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
2088 | event->state = PERF_EVENT_STATE_INACTIVE; |
2089 | event->oncpu = -1; | |
44377277 AS |
2090 | ret = -EAGAIN; |
2091 | goto out; | |
235c7fc7 IM |
2092 | } |
2093 | ||
00a2916f PZ |
2094 | event->tstamp_running += tstamp - event->tstamp_stopped; |
2095 | ||
cdd6c482 | 2096 | if (!is_software_event(event)) |
3b6f9e5c | 2097 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2098 | if (!ctx->nr_active++) |
2099 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2100 | if (event->attr.freq && event->attr.sample_freq) |
2101 | ctx->nr_freq++; | |
235c7fc7 | 2102 | |
cdd6c482 | 2103 | if (event->attr.exclusive) |
3b6f9e5c PM |
2104 | cpuctx->exclusive = 1; |
2105 | ||
44377277 AS |
2106 | out: |
2107 | perf_pmu_enable(event->pmu); | |
2108 | ||
2109 | return ret; | |
235c7fc7 IM |
2110 | } |
2111 | ||
6751b71e | 2112 | static int |
cdd6c482 | 2113 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2114 | struct perf_cpu_context *cpuctx, |
6e37738a | 2115 | struct perf_event_context *ctx) |
6751b71e | 2116 | { |
6bde9b6c | 2117 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2118 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2119 | u64 now = ctx->time; |
2120 | bool simulate = false; | |
6751b71e | 2121 | |
cdd6c482 | 2122 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2123 | return 0; |
2124 | ||
fbbe0701 | 2125 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2126 | |
9ffcfa6f | 2127 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2128 | pmu->cancel_txn(pmu); |
272325c4 | 2129 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2130 | return -EAGAIN; |
90151c35 | 2131 | } |
6751b71e PM |
2132 | |
2133 | /* | |
2134 | * Schedule in siblings as one group (if any): | |
2135 | */ | |
cdd6c482 | 2136 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2137 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2138 | partial_group = event; |
6751b71e PM |
2139 | goto group_error; |
2140 | } | |
2141 | } | |
2142 | ||
9ffcfa6f | 2143 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2144 | return 0; |
9ffcfa6f | 2145 | |
6751b71e PM |
2146 | group_error: |
2147 | /* | |
2148 | * Groups can be scheduled in as one unit only, so undo any | |
2149 | * partial group before returning: | |
d7842da4 SE |
2150 | * The events up to the failed event are scheduled out normally, |
2151 | * tstamp_stopped will be updated. | |
2152 | * | |
2153 | * The failed events and the remaining siblings need to have | |
2154 | * their timings updated as if they had gone thru event_sched_in() | |
2155 | * and event_sched_out(). This is required to get consistent timings | |
2156 | * across the group. This also takes care of the case where the group | |
2157 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2158 | * the time the event was actually stopped, such that time delta | |
2159 | * calculation in update_event_times() is correct. | |
6751b71e | 2160 | */ |
cdd6c482 IM |
2161 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2162 | if (event == partial_group) | |
d7842da4 SE |
2163 | simulate = true; |
2164 | ||
2165 | if (simulate) { | |
2166 | event->tstamp_running += now - event->tstamp_stopped; | |
2167 | event->tstamp_stopped = now; | |
2168 | } else { | |
2169 | event_sched_out(event, cpuctx, ctx); | |
2170 | } | |
6751b71e | 2171 | } |
9ffcfa6f | 2172 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2173 | |
ad5133b7 | 2174 | pmu->cancel_txn(pmu); |
90151c35 | 2175 | |
272325c4 | 2176 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2177 | |
6751b71e PM |
2178 | return -EAGAIN; |
2179 | } | |
2180 | ||
3b6f9e5c | 2181 | /* |
cdd6c482 | 2182 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2183 | */ |
cdd6c482 | 2184 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2185 | struct perf_cpu_context *cpuctx, |
2186 | int can_add_hw) | |
2187 | { | |
2188 | /* | |
cdd6c482 | 2189 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2190 | */ |
4ff6a8de | 2191 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2192 | return 1; |
2193 | /* | |
2194 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2195 | * events can go on. |
3b6f9e5c PM |
2196 | */ |
2197 | if (cpuctx->exclusive) | |
2198 | return 0; | |
2199 | /* | |
2200 | * If this group is exclusive and there are already | |
cdd6c482 | 2201 | * events on the CPU, it can't go on. |
3b6f9e5c | 2202 | */ |
cdd6c482 | 2203 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2204 | return 0; |
2205 | /* | |
2206 | * Otherwise, try to add it if all previous groups were able | |
2207 | * to go on. | |
2208 | */ | |
2209 | return can_add_hw; | |
2210 | } | |
2211 | ||
cdd6c482 IM |
2212 | static void add_event_to_ctx(struct perf_event *event, |
2213 | struct perf_event_context *ctx) | |
53cfbf59 | 2214 | { |
4158755d SE |
2215 | u64 tstamp = perf_event_time(event); |
2216 | ||
cdd6c482 | 2217 | list_add_event(event, ctx); |
8a49542c | 2218 | perf_group_attach(event); |
4158755d SE |
2219 | event->tstamp_enabled = tstamp; |
2220 | event->tstamp_running = tstamp; | |
2221 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2222 | } |
2223 | ||
bd2afa49 PZ |
2224 | static void ctx_sched_out(struct perf_event_context *ctx, |
2225 | struct perf_cpu_context *cpuctx, | |
2226 | enum event_type_t event_type); | |
2c29ef0f PZ |
2227 | static void |
2228 | ctx_sched_in(struct perf_event_context *ctx, | |
2229 | struct perf_cpu_context *cpuctx, | |
2230 | enum event_type_t event_type, | |
2231 | struct task_struct *task); | |
fe4b04fa | 2232 | |
bd2afa49 | 2233 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2234 | struct perf_event_context *ctx, |
2235 | enum event_type_t event_type) | |
bd2afa49 PZ |
2236 | { |
2237 | if (!cpuctx->task_ctx) | |
2238 | return; | |
2239 | ||
2240 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2241 | return; | |
2242 | ||
487f05e1 | 2243 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2244 | } |
2245 | ||
dce5855b PZ |
2246 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2247 | struct perf_event_context *ctx, | |
2248 | struct task_struct *task) | |
2249 | { | |
2250 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2251 | if (ctx) | |
2252 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2253 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2254 | if (ctx) | |
2255 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2256 | } | |
2257 | ||
487f05e1 AS |
2258 | /* |
2259 | * We want to maintain the following priority of scheduling: | |
2260 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2261 | * - task pinned (EVENT_PINNED) | |
2262 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2263 | * - task flexible (EVENT_FLEXIBLE). | |
2264 | * | |
2265 | * In order to avoid unscheduling and scheduling back in everything every | |
2266 | * time an event is added, only do it for the groups of equal priority and | |
2267 | * below. | |
2268 | * | |
2269 | * This can be called after a batch operation on task events, in which case | |
2270 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2271 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2272 | */ | |
3e349507 | 2273 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2274 | struct perf_event_context *task_ctx, |
2275 | enum event_type_t event_type) | |
0017960f | 2276 | { |
487f05e1 AS |
2277 | enum event_type_t ctx_event_type = event_type & EVENT_ALL; |
2278 | bool cpu_event = !!(event_type & EVENT_CPU); | |
2279 | ||
2280 | /* | |
2281 | * If pinned groups are involved, flexible groups also need to be | |
2282 | * scheduled out. | |
2283 | */ | |
2284 | if (event_type & EVENT_PINNED) | |
2285 | event_type |= EVENT_FLEXIBLE; | |
2286 | ||
3e349507 PZ |
2287 | perf_pmu_disable(cpuctx->ctx.pmu); |
2288 | if (task_ctx) | |
487f05e1 AS |
2289 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2290 | ||
2291 | /* | |
2292 | * Decide which cpu ctx groups to schedule out based on the types | |
2293 | * of events that caused rescheduling: | |
2294 | * - EVENT_CPU: schedule out corresponding groups; | |
2295 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2296 | * - otherwise, do nothing more. | |
2297 | */ | |
2298 | if (cpu_event) | |
2299 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2300 | else if (ctx_event_type & EVENT_PINNED) | |
2301 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2302 | ||
3e349507 PZ |
2303 | perf_event_sched_in(cpuctx, task_ctx, current); |
2304 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2305 | } |
2306 | ||
0793a61d | 2307 | /* |
cdd6c482 | 2308 | * Cross CPU call to install and enable a performance event |
682076ae | 2309 | * |
a096309b PZ |
2310 | * Very similar to remote_function() + event_function() but cannot assume that |
2311 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2312 | */ |
fe4b04fa | 2313 | static int __perf_install_in_context(void *info) |
0793a61d | 2314 | { |
a096309b PZ |
2315 | struct perf_event *event = info; |
2316 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2317 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2318 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2319 | bool reprogram = true; |
a096309b | 2320 | int ret = 0; |
0793a61d | 2321 | |
63b6da39 | 2322 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2323 | if (ctx->task) { |
b58f6b0d PZ |
2324 | raw_spin_lock(&ctx->lock); |
2325 | task_ctx = ctx; | |
a096309b | 2326 | |
63cae12b | 2327 | reprogram = (ctx->task == current); |
b58f6b0d | 2328 | |
39a43640 | 2329 | /* |
63cae12b PZ |
2330 | * If the task is running, it must be running on this CPU, |
2331 | * otherwise we cannot reprogram things. | |
2332 | * | |
2333 | * If its not running, we don't care, ctx->lock will | |
2334 | * serialize against it becoming runnable. | |
39a43640 | 2335 | */ |
63cae12b PZ |
2336 | if (task_curr(ctx->task) && !reprogram) { |
2337 | ret = -ESRCH; | |
2338 | goto unlock; | |
2339 | } | |
a096309b | 2340 | |
63cae12b | 2341 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2342 | } else if (task_ctx) { |
2343 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2344 | } |
b58f6b0d | 2345 | |
63cae12b | 2346 | if (reprogram) { |
a096309b PZ |
2347 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2348 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2349 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2350 | } else { |
2351 | add_event_to_ctx(event, ctx); | |
2352 | } | |
2353 | ||
63b6da39 | 2354 | unlock: |
2c29ef0f | 2355 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2356 | |
a096309b | 2357 | return ret; |
0793a61d TG |
2358 | } |
2359 | ||
2360 | /* | |
a096309b PZ |
2361 | * Attach a performance event to a context. |
2362 | * | |
2363 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2364 | */ |
2365 | static void | |
cdd6c482 IM |
2366 | perf_install_in_context(struct perf_event_context *ctx, |
2367 | struct perf_event *event, | |
0793a61d TG |
2368 | int cpu) |
2369 | { | |
a096309b | 2370 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2371 | |
fe4b04fa PZ |
2372 | lockdep_assert_held(&ctx->mutex); |
2373 | ||
0cda4c02 YZ |
2374 | if (event->cpu != -1) |
2375 | event->cpu = cpu; | |
c3f00c70 | 2376 | |
0b8f1e2e PZ |
2377 | /* |
2378 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2379 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2380 | */ | |
2381 | smp_store_release(&event->ctx, ctx); | |
2382 | ||
a096309b PZ |
2383 | if (!task) { |
2384 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2385 | return; | |
2386 | } | |
2387 | ||
2388 | /* | |
2389 | * Should not happen, we validate the ctx is still alive before calling. | |
2390 | */ | |
2391 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2392 | return; | |
2393 | ||
39a43640 PZ |
2394 | /* |
2395 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2396 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2397 | * |
2398 | * Instead we use task_curr(), which tells us if the task is running. | |
2399 | * However, since we use task_curr() outside of rq::lock, we can race | |
2400 | * against the actual state. This means the result can be wrong. | |
2401 | * | |
2402 | * If we get a false positive, we retry, this is harmless. | |
2403 | * | |
2404 | * If we get a false negative, things are complicated. If we are after | |
2405 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2406 | * value must be correct. If we're before, it doesn't matter since | |
2407 | * perf_event_context_sched_in() will program the counter. | |
2408 | * | |
2409 | * However, this hinges on the remote context switch having observed | |
2410 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2411 | * ctx::lock in perf_event_context_sched_in(). | |
2412 | * | |
2413 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2414 | * we know any future context switch of task must see the | |
2415 | * perf_event_ctpx[] store. | |
39a43640 | 2416 | */ |
63cae12b | 2417 | |
63b6da39 | 2418 | /* |
63cae12b PZ |
2419 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2420 | * task_cpu() load, such that if the IPI then does not find the task | |
2421 | * running, a future context switch of that task must observe the | |
2422 | * store. | |
63b6da39 | 2423 | */ |
63cae12b PZ |
2424 | smp_mb(); |
2425 | again: | |
2426 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2427 | return; |
2428 | ||
2429 | raw_spin_lock_irq(&ctx->lock); | |
2430 | task = ctx->task; | |
84c4e620 | 2431 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2432 | /* |
2433 | * Cannot happen because we already checked above (which also | |
2434 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2435 | * against perf_event_exit_task_context(). | |
2436 | */ | |
63b6da39 PZ |
2437 | raw_spin_unlock_irq(&ctx->lock); |
2438 | return; | |
2439 | } | |
39a43640 | 2440 | /* |
63cae12b PZ |
2441 | * If the task is not running, ctx->lock will avoid it becoming so, |
2442 | * thus we can safely install the event. | |
39a43640 | 2443 | */ |
63cae12b PZ |
2444 | if (task_curr(task)) { |
2445 | raw_spin_unlock_irq(&ctx->lock); | |
2446 | goto again; | |
2447 | } | |
2448 | add_event_to_ctx(event, ctx); | |
2449 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2450 | } |
2451 | ||
fa289bec | 2452 | /* |
cdd6c482 | 2453 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2454 | * Enabling the leader of a group effectively enables all |
2455 | * the group members that aren't explicitly disabled, so we | |
2456 | * have to update their ->tstamp_enabled also. | |
2457 | * Note: this works for group members as well as group leaders | |
2458 | * since the non-leader members' sibling_lists will be empty. | |
2459 | */ | |
1d9b482e | 2460 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2461 | { |
cdd6c482 | 2462 | struct perf_event *sub; |
4158755d | 2463 | u64 tstamp = perf_event_time(event); |
fa289bec | 2464 | |
cdd6c482 | 2465 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2466 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2467 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2468 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2469 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2470 | } |
fa289bec PM |
2471 | } |
2472 | ||
d859e29f | 2473 | /* |
cdd6c482 | 2474 | * Cross CPU call to enable a performance event |
d859e29f | 2475 | */ |
fae3fde6 PZ |
2476 | static void __perf_event_enable(struct perf_event *event, |
2477 | struct perf_cpu_context *cpuctx, | |
2478 | struct perf_event_context *ctx, | |
2479 | void *info) | |
04289bb9 | 2480 | { |
cdd6c482 | 2481 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2482 | struct perf_event_context *task_ctx; |
04289bb9 | 2483 | |
6e801e01 PZ |
2484 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2485 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2486 | return; |
3cbed429 | 2487 | |
bd2afa49 PZ |
2488 | if (ctx->is_active) |
2489 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2490 | ||
1d9b482e | 2491 | __perf_event_mark_enabled(event); |
04289bb9 | 2492 | |
fae3fde6 PZ |
2493 | if (!ctx->is_active) |
2494 | return; | |
2495 | ||
e5d1367f | 2496 | if (!event_filter_match(event)) { |
bd2afa49 | 2497 | if (is_cgroup_event(event)) |
e5d1367f | 2498 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2499 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2500 | return; |
e5d1367f | 2501 | } |
f4c4176f | 2502 | |
04289bb9 | 2503 | /* |
cdd6c482 | 2504 | * If the event is in a group and isn't the group leader, |
d859e29f | 2505 | * then don't put it on unless the group is on. |
04289bb9 | 2506 | */ |
bd2afa49 PZ |
2507 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2508 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2509 | return; |
bd2afa49 | 2510 | } |
fe4b04fa | 2511 | |
fae3fde6 PZ |
2512 | task_ctx = cpuctx->task_ctx; |
2513 | if (ctx->task) | |
2514 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2515 | |
487f05e1 | 2516 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2517 | } |
2518 | ||
d859e29f | 2519 | /* |
cdd6c482 | 2520 | * Enable a event. |
c93f7669 | 2521 | * |
cdd6c482 IM |
2522 | * If event->ctx is a cloned context, callers must make sure that |
2523 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2524 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2525 | * perf_event_for_each_child or perf_event_for_each as described |
2526 | * for perf_event_disable. | |
d859e29f | 2527 | */ |
f63a8daa | 2528 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2529 | { |
cdd6c482 | 2530 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2531 | |
7b648018 | 2532 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2533 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2534 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2535 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2536 | return; |
2537 | } | |
2538 | ||
d859e29f | 2539 | /* |
cdd6c482 | 2540 | * If the event is in error state, clear that first. |
7b648018 PZ |
2541 | * |
2542 | * That way, if we see the event in error state below, we know that it | |
2543 | * has gone back into error state, as distinct from the task having | |
2544 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2545 | */ |
cdd6c482 IM |
2546 | if (event->state == PERF_EVENT_STATE_ERROR) |
2547 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2548 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2549 | |
fae3fde6 | 2550 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2551 | } |
f63a8daa PZ |
2552 | |
2553 | /* | |
2554 | * See perf_event_disable(); | |
2555 | */ | |
2556 | void perf_event_enable(struct perf_event *event) | |
2557 | { | |
2558 | struct perf_event_context *ctx; | |
2559 | ||
2560 | ctx = perf_event_ctx_lock(event); | |
2561 | _perf_event_enable(event); | |
2562 | perf_event_ctx_unlock(event, ctx); | |
2563 | } | |
dcfce4a0 | 2564 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2565 | |
375637bc AS |
2566 | struct stop_event_data { |
2567 | struct perf_event *event; | |
2568 | unsigned int restart; | |
2569 | }; | |
2570 | ||
95ff4ca2 AS |
2571 | static int __perf_event_stop(void *info) |
2572 | { | |
375637bc AS |
2573 | struct stop_event_data *sd = info; |
2574 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2575 | |
375637bc | 2576 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2577 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2578 | return 0; | |
2579 | ||
2580 | /* matches smp_wmb() in event_sched_in() */ | |
2581 | smp_rmb(); | |
2582 | ||
2583 | /* | |
2584 | * There is a window with interrupts enabled before we get here, | |
2585 | * so we need to check again lest we try to stop another CPU's event. | |
2586 | */ | |
2587 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2588 | return -EAGAIN; | |
2589 | ||
2590 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2591 | ||
375637bc AS |
2592 | /* |
2593 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2594 | * but it is only used for events with AUX ring buffer, and such | |
2595 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2596 | * see comments in perf_aux_output_begin(). | |
2597 | * | |
2598 | * Since this is happening on a event-local CPU, no trace is lost | |
2599 | * while restarting. | |
2600 | */ | |
2601 | if (sd->restart) | |
c9bbdd48 | 2602 | event->pmu->start(event, 0); |
375637bc | 2603 | |
95ff4ca2 AS |
2604 | return 0; |
2605 | } | |
2606 | ||
767ae086 | 2607 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2608 | { |
2609 | struct stop_event_data sd = { | |
2610 | .event = event, | |
767ae086 | 2611 | .restart = restart, |
375637bc AS |
2612 | }; |
2613 | int ret = 0; | |
2614 | ||
2615 | do { | |
2616 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2617 | return 0; | |
2618 | ||
2619 | /* matches smp_wmb() in event_sched_in() */ | |
2620 | smp_rmb(); | |
2621 | ||
2622 | /* | |
2623 | * We only want to restart ACTIVE events, so if the event goes | |
2624 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2625 | * fall through with ret==-ENXIO. | |
2626 | */ | |
2627 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2628 | __perf_event_stop, &sd); | |
2629 | } while (ret == -EAGAIN); | |
2630 | ||
2631 | return ret; | |
2632 | } | |
2633 | ||
2634 | /* | |
2635 | * In order to contain the amount of racy and tricky in the address filter | |
2636 | * configuration management, it is a two part process: | |
2637 | * | |
2638 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2639 | * we update the addresses of corresponding vmas in | |
2640 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2641 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2642 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2643 | * if the generation has changed since the previous call. | |
2644 | * | |
2645 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2646 | * | |
2647 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2648 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2649 | * ioctl; | |
2650 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2651 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2652 | * for reading; | |
2653 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2654 | * of exec. | |
2655 | */ | |
2656 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2657 | { | |
2658 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2659 | ||
2660 | if (!has_addr_filter(event)) | |
2661 | return; | |
2662 | ||
2663 | raw_spin_lock(&ifh->lock); | |
2664 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2665 | event->pmu->addr_filters_sync(event); | |
2666 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2667 | } | |
2668 | raw_spin_unlock(&ifh->lock); | |
2669 | } | |
2670 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2671 | ||
f63a8daa | 2672 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2673 | { |
2023b359 | 2674 | /* |
cdd6c482 | 2675 | * not supported on inherited events |
2023b359 | 2676 | */ |
2e939d1d | 2677 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2678 | return -EINVAL; |
2679 | ||
cdd6c482 | 2680 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2681 | _perf_event_enable(event); |
2023b359 PZ |
2682 | |
2683 | return 0; | |
79f14641 | 2684 | } |
f63a8daa PZ |
2685 | |
2686 | /* | |
2687 | * See perf_event_disable() | |
2688 | */ | |
2689 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2690 | { | |
2691 | struct perf_event_context *ctx; | |
2692 | int ret; | |
2693 | ||
2694 | ctx = perf_event_ctx_lock(event); | |
2695 | ret = _perf_event_refresh(event, refresh); | |
2696 | perf_event_ctx_unlock(event, ctx); | |
2697 | ||
2698 | return ret; | |
2699 | } | |
26ca5c11 | 2700 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2701 | |
5b0311e1 FW |
2702 | static void ctx_sched_out(struct perf_event_context *ctx, |
2703 | struct perf_cpu_context *cpuctx, | |
2704 | enum event_type_t event_type) | |
235c7fc7 | 2705 | { |
db24d33e | 2706 | int is_active = ctx->is_active; |
c994d613 | 2707 | struct perf_event *event; |
235c7fc7 | 2708 | |
c994d613 | 2709 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2710 | |
39a43640 PZ |
2711 | if (likely(!ctx->nr_events)) { |
2712 | /* | |
2713 | * See __perf_remove_from_context(). | |
2714 | */ | |
2715 | WARN_ON_ONCE(ctx->is_active); | |
2716 | if (ctx->task) | |
2717 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2718 | return; |
39a43640 PZ |
2719 | } |
2720 | ||
db24d33e | 2721 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2722 | if (!(ctx->is_active & EVENT_ALL)) |
2723 | ctx->is_active = 0; | |
2724 | ||
63e30d3e PZ |
2725 | if (ctx->task) { |
2726 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2727 | if (!ctx->is_active) | |
2728 | cpuctx->task_ctx = NULL; | |
2729 | } | |
facc4307 | 2730 | |
8fdc6539 PZ |
2731 | /* |
2732 | * Always update time if it was set; not only when it changes. | |
2733 | * Otherwise we can 'forget' to update time for any but the last | |
2734 | * context we sched out. For example: | |
2735 | * | |
2736 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2737 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2738 | * | |
2739 | * would only update time for the pinned events. | |
2740 | */ | |
3cbaa590 PZ |
2741 | if (is_active & EVENT_TIME) { |
2742 | /* update (and stop) ctx time */ | |
2743 | update_context_time(ctx); | |
2744 | update_cgrp_time_from_cpuctx(cpuctx); | |
2745 | } | |
2746 | ||
8fdc6539 PZ |
2747 | is_active ^= ctx->is_active; /* changed bits */ |
2748 | ||
3cbaa590 | 2749 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2750 | return; |
5b0311e1 | 2751 | |
075e0b00 | 2752 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2753 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2754 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2755 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2756 | } |
889ff015 | 2757 | |
3cbaa590 | 2758 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2759 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2760 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2761 | } |
1b9a644f | 2762 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2763 | } |
2764 | ||
564c2b21 | 2765 | /* |
5a3126d4 PZ |
2766 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2767 | * cloned from the same version of the same context. | |
2768 | * | |
2769 | * Equivalence is measured using a generation number in the context that is | |
2770 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2771 | * and list_del_event(). | |
564c2b21 | 2772 | */ |
cdd6c482 IM |
2773 | static int context_equiv(struct perf_event_context *ctx1, |
2774 | struct perf_event_context *ctx2) | |
564c2b21 | 2775 | { |
211de6eb PZ |
2776 | lockdep_assert_held(&ctx1->lock); |
2777 | lockdep_assert_held(&ctx2->lock); | |
2778 | ||
5a3126d4 PZ |
2779 | /* Pinning disables the swap optimization */ |
2780 | if (ctx1->pin_count || ctx2->pin_count) | |
2781 | return 0; | |
2782 | ||
2783 | /* If ctx1 is the parent of ctx2 */ | |
2784 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2785 | return 1; | |
2786 | ||
2787 | /* If ctx2 is the parent of ctx1 */ | |
2788 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2789 | return 1; | |
2790 | ||
2791 | /* | |
2792 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2793 | * hierarchy, see perf_event_init_context(). | |
2794 | */ | |
2795 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2796 | ctx1->parent_gen == ctx2->parent_gen) | |
2797 | return 1; | |
2798 | ||
2799 | /* Unmatched */ | |
2800 | return 0; | |
564c2b21 PM |
2801 | } |
2802 | ||
cdd6c482 IM |
2803 | static void __perf_event_sync_stat(struct perf_event *event, |
2804 | struct perf_event *next_event) | |
bfbd3381 PZ |
2805 | { |
2806 | u64 value; | |
2807 | ||
cdd6c482 | 2808 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2809 | return; |
2810 | ||
2811 | /* | |
cdd6c482 | 2812 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2813 | * because we're in the middle of a context switch and have IRQs |
2814 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2815 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2816 | * don't need to use it. |
2817 | */ | |
cdd6c482 IM |
2818 | switch (event->state) { |
2819 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2820 | event->pmu->read(event); |
2821 | /* fall-through */ | |
bfbd3381 | 2822 | |
cdd6c482 IM |
2823 | case PERF_EVENT_STATE_INACTIVE: |
2824 | update_event_times(event); | |
bfbd3381 PZ |
2825 | break; |
2826 | ||
2827 | default: | |
2828 | break; | |
2829 | } | |
2830 | ||
2831 | /* | |
cdd6c482 | 2832 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2833 | * values when we flip the contexts. |
2834 | */ | |
e7850595 PZ |
2835 | value = local64_read(&next_event->count); |
2836 | value = local64_xchg(&event->count, value); | |
2837 | local64_set(&next_event->count, value); | |
bfbd3381 | 2838 | |
cdd6c482 IM |
2839 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2840 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2841 | |
bfbd3381 | 2842 | /* |
19d2e755 | 2843 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2844 | */ |
cdd6c482 IM |
2845 | perf_event_update_userpage(event); |
2846 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2847 | } |
2848 | ||
cdd6c482 IM |
2849 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2850 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2851 | { |
cdd6c482 | 2852 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2853 | |
2854 | if (!ctx->nr_stat) | |
2855 | return; | |
2856 | ||
02ffdbc8 PZ |
2857 | update_context_time(ctx); |
2858 | ||
cdd6c482 IM |
2859 | event = list_first_entry(&ctx->event_list, |
2860 | struct perf_event, event_entry); | |
bfbd3381 | 2861 | |
cdd6c482 IM |
2862 | next_event = list_first_entry(&next_ctx->event_list, |
2863 | struct perf_event, event_entry); | |
bfbd3381 | 2864 | |
cdd6c482 IM |
2865 | while (&event->event_entry != &ctx->event_list && |
2866 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2867 | |
cdd6c482 | 2868 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2869 | |
cdd6c482 IM |
2870 | event = list_next_entry(event, event_entry); |
2871 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2872 | } |
2873 | } | |
2874 | ||
fe4b04fa PZ |
2875 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2876 | struct task_struct *next) | |
0793a61d | 2877 | { |
8dc85d54 | 2878 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2879 | struct perf_event_context *next_ctx; |
5a3126d4 | 2880 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2881 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2882 | int do_switch = 1; |
0793a61d | 2883 | |
108b02cf PZ |
2884 | if (likely(!ctx)) |
2885 | return; | |
10989fb2 | 2886 | |
108b02cf PZ |
2887 | cpuctx = __get_cpu_context(ctx); |
2888 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2889 | return; |
2890 | ||
c93f7669 | 2891 | rcu_read_lock(); |
8dc85d54 | 2892 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2893 | if (!next_ctx) |
2894 | goto unlock; | |
2895 | ||
2896 | parent = rcu_dereference(ctx->parent_ctx); | |
2897 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2898 | ||
2899 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2900 | if (!parent && !next_parent) |
5a3126d4 PZ |
2901 | goto unlock; |
2902 | ||
2903 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2904 | /* |
2905 | * Looks like the two contexts are clones, so we might be | |
2906 | * able to optimize the context switch. We lock both | |
2907 | * contexts and check that they are clones under the | |
2908 | * lock (including re-checking that neither has been | |
2909 | * uncloned in the meantime). It doesn't matter which | |
2910 | * order we take the locks because no other cpu could | |
2911 | * be trying to lock both of these tasks. | |
2912 | */ | |
e625cce1 TG |
2913 | raw_spin_lock(&ctx->lock); |
2914 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2915 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2916 | WRITE_ONCE(ctx->task, next); |
2917 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2918 | |
2919 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2920 | ||
63b6da39 PZ |
2921 | /* |
2922 | * RCU_INIT_POINTER here is safe because we've not | |
2923 | * modified the ctx and the above modification of | |
2924 | * ctx->task and ctx->task_ctx_data are immaterial | |
2925 | * since those values are always verified under | |
2926 | * ctx->lock which we're now holding. | |
2927 | */ | |
2928 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2929 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2930 | ||
c93f7669 | 2931 | do_switch = 0; |
bfbd3381 | 2932 | |
cdd6c482 | 2933 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2934 | } |
e625cce1 TG |
2935 | raw_spin_unlock(&next_ctx->lock); |
2936 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2937 | } |
5a3126d4 | 2938 | unlock: |
c93f7669 | 2939 | rcu_read_unlock(); |
564c2b21 | 2940 | |
c93f7669 | 2941 | if (do_switch) { |
facc4307 | 2942 | raw_spin_lock(&ctx->lock); |
487f05e1 | 2943 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 2944 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2945 | } |
0793a61d TG |
2946 | } |
2947 | ||
e48c1788 PZ |
2948 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2949 | ||
ba532500 YZ |
2950 | void perf_sched_cb_dec(struct pmu *pmu) |
2951 | { | |
e48c1788 PZ |
2952 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2953 | ||
ba532500 | 2954 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2955 | |
2956 | if (!--cpuctx->sched_cb_usage) | |
2957 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2958 | } |
2959 | ||
e48c1788 | 2960 | |
ba532500 YZ |
2961 | void perf_sched_cb_inc(struct pmu *pmu) |
2962 | { | |
e48c1788 PZ |
2963 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2964 | ||
2965 | if (!cpuctx->sched_cb_usage++) | |
2966 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2967 | ||
ba532500 YZ |
2968 | this_cpu_inc(perf_sched_cb_usages); |
2969 | } | |
2970 | ||
2971 | /* | |
2972 | * This function provides the context switch callback to the lower code | |
2973 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2974 | * |
2975 | * This callback is relevant even to per-cpu events; for example multi event | |
2976 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2977 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2978 | */ |
2979 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2980 | struct task_struct *next, | |
2981 | bool sched_in) | |
2982 | { | |
2983 | struct perf_cpu_context *cpuctx; | |
2984 | struct pmu *pmu; | |
ba532500 YZ |
2985 | |
2986 | if (prev == next) | |
2987 | return; | |
2988 | ||
e48c1788 | 2989 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 2990 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 2991 | |
e48c1788 PZ |
2992 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2993 | continue; | |
ba532500 | 2994 | |
e48c1788 PZ |
2995 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
2996 | perf_pmu_disable(pmu); | |
ba532500 | 2997 | |
e48c1788 | 2998 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 2999 | |
e48c1788 PZ |
3000 | perf_pmu_enable(pmu); |
3001 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3002 | } |
ba532500 YZ |
3003 | } |
3004 | ||
45ac1403 AH |
3005 | static void perf_event_switch(struct task_struct *task, |
3006 | struct task_struct *next_prev, bool sched_in); | |
3007 | ||
8dc85d54 PZ |
3008 | #define for_each_task_context_nr(ctxn) \ |
3009 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3010 | ||
3011 | /* | |
3012 | * Called from scheduler to remove the events of the current task, | |
3013 | * with interrupts disabled. | |
3014 | * | |
3015 | * We stop each event and update the event value in event->count. | |
3016 | * | |
3017 | * This does not protect us against NMI, but disable() | |
3018 | * sets the disabled bit in the control field of event _before_ | |
3019 | * accessing the event control register. If a NMI hits, then it will | |
3020 | * not restart the event. | |
3021 | */ | |
ab0cce56 JO |
3022 | void __perf_event_task_sched_out(struct task_struct *task, |
3023 | struct task_struct *next) | |
8dc85d54 PZ |
3024 | { |
3025 | int ctxn; | |
3026 | ||
ba532500 YZ |
3027 | if (__this_cpu_read(perf_sched_cb_usages)) |
3028 | perf_pmu_sched_task(task, next, false); | |
3029 | ||
45ac1403 AH |
3030 | if (atomic_read(&nr_switch_events)) |
3031 | perf_event_switch(task, next, false); | |
3032 | ||
8dc85d54 PZ |
3033 | for_each_task_context_nr(ctxn) |
3034 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3035 | |
3036 | /* | |
3037 | * if cgroup events exist on this CPU, then we need | |
3038 | * to check if we have to switch out PMU state. | |
3039 | * cgroup event are system-wide mode only | |
3040 | */ | |
4a32fea9 | 3041 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3042 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3043 | } |
3044 | ||
5b0311e1 FW |
3045 | /* |
3046 | * Called with IRQs disabled | |
3047 | */ | |
3048 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3049 | enum event_type_t event_type) | |
3050 | { | |
3051 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3052 | } |
3053 | ||
235c7fc7 | 3054 | static void |
5b0311e1 | 3055 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 3056 | struct perf_cpu_context *cpuctx) |
0793a61d | 3057 | { |
cdd6c482 | 3058 | struct perf_event *event; |
0793a61d | 3059 | |
889ff015 FW |
3060 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
3061 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3062 | continue; |
5632ab12 | 3063 | if (!event_filter_match(event)) |
3b6f9e5c PM |
3064 | continue; |
3065 | ||
e5d1367f SE |
3066 | /* may need to reset tstamp_enabled */ |
3067 | if (is_cgroup_event(event)) | |
3068 | perf_cgroup_mark_enabled(event, ctx); | |
3069 | ||
8c9ed8e1 | 3070 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 3071 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
3072 | |
3073 | /* | |
3074 | * If this pinned group hasn't been scheduled, | |
3075 | * put it in error state. | |
3076 | */ | |
cdd6c482 IM |
3077 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3078 | update_group_times(event); | |
3079 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 3080 | } |
3b6f9e5c | 3081 | } |
5b0311e1 FW |
3082 | } |
3083 | ||
3084 | static void | |
3085 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 3086 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
3087 | { |
3088 | struct perf_event *event; | |
3089 | int can_add_hw = 1; | |
3b6f9e5c | 3090 | |
889ff015 FW |
3091 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
3092 | /* Ignore events in OFF or ERROR state */ | |
3093 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3094 | continue; |
04289bb9 IM |
3095 | /* |
3096 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 3097 | * of events: |
04289bb9 | 3098 | */ |
5632ab12 | 3099 | if (!event_filter_match(event)) |
0793a61d TG |
3100 | continue; |
3101 | ||
e5d1367f SE |
3102 | /* may need to reset tstamp_enabled */ |
3103 | if (is_cgroup_event(event)) | |
3104 | perf_cgroup_mark_enabled(event, ctx); | |
3105 | ||
9ed6060d | 3106 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3107 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3108 | can_add_hw = 0; |
9ed6060d | 3109 | } |
0793a61d | 3110 | } |
5b0311e1 FW |
3111 | } |
3112 | ||
3113 | static void | |
3114 | ctx_sched_in(struct perf_event_context *ctx, | |
3115 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3116 | enum event_type_t event_type, |
3117 | struct task_struct *task) | |
5b0311e1 | 3118 | { |
db24d33e | 3119 | int is_active = ctx->is_active; |
c994d613 PZ |
3120 | u64 now; |
3121 | ||
3122 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3123 | |
5b0311e1 | 3124 | if (likely(!ctx->nr_events)) |
facc4307 | 3125 | return; |
5b0311e1 | 3126 | |
3cbaa590 | 3127 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3128 | if (ctx->task) { |
3129 | if (!is_active) | |
3130 | cpuctx->task_ctx = ctx; | |
3131 | else | |
3132 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3133 | } | |
3134 | ||
3cbaa590 PZ |
3135 | is_active ^= ctx->is_active; /* changed bits */ |
3136 | ||
3137 | if (is_active & EVENT_TIME) { | |
3138 | /* start ctx time */ | |
3139 | now = perf_clock(); | |
3140 | ctx->timestamp = now; | |
3141 | perf_cgroup_set_timestamp(task, ctx); | |
3142 | } | |
3143 | ||
5b0311e1 FW |
3144 | /* |
3145 | * First go through the list and put on any pinned groups | |
3146 | * in order to give them the best chance of going on. | |
3147 | */ | |
3cbaa590 | 3148 | if (is_active & EVENT_PINNED) |
6e37738a | 3149 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3150 | |
3151 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3152 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3153 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3154 | } |
3155 | ||
329c0e01 | 3156 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3157 | enum event_type_t event_type, |
3158 | struct task_struct *task) | |
329c0e01 FW |
3159 | { |
3160 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3161 | ||
e5d1367f | 3162 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3163 | } |
3164 | ||
e5d1367f SE |
3165 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3166 | struct task_struct *task) | |
235c7fc7 | 3167 | { |
108b02cf | 3168 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3169 | |
108b02cf | 3170 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3171 | if (cpuctx->task_ctx == ctx) |
3172 | return; | |
3173 | ||
facc4307 | 3174 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3175 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3176 | /* |
3177 | * We want to keep the following priority order: | |
3178 | * cpu pinned (that don't need to move), task pinned, | |
3179 | * cpu flexible, task flexible. | |
fe45bafb AS |
3180 | * |
3181 | * However, if task's ctx is not carrying any pinned | |
3182 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3183 | */ |
fe45bafb AS |
3184 | if (!list_empty(&ctx->pinned_groups)) |
3185 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3186 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3187 | perf_pmu_enable(ctx->pmu); |
3188 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3189 | } |
3190 | ||
8dc85d54 PZ |
3191 | /* |
3192 | * Called from scheduler to add the events of the current task | |
3193 | * with interrupts disabled. | |
3194 | * | |
3195 | * We restore the event value and then enable it. | |
3196 | * | |
3197 | * This does not protect us against NMI, but enable() | |
3198 | * sets the enabled bit in the control field of event _before_ | |
3199 | * accessing the event control register. If a NMI hits, then it will | |
3200 | * keep the event running. | |
3201 | */ | |
ab0cce56 JO |
3202 | void __perf_event_task_sched_in(struct task_struct *prev, |
3203 | struct task_struct *task) | |
8dc85d54 PZ |
3204 | { |
3205 | struct perf_event_context *ctx; | |
3206 | int ctxn; | |
3207 | ||
7e41d177 PZ |
3208 | /* |
3209 | * If cgroup events exist on this CPU, then we need to check if we have | |
3210 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3211 | * | |
3212 | * Since cgroup events are CPU events, we must schedule these in before | |
3213 | * we schedule in the task events. | |
3214 | */ | |
3215 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3216 | perf_cgroup_sched_in(prev, task); | |
3217 | ||
8dc85d54 PZ |
3218 | for_each_task_context_nr(ctxn) { |
3219 | ctx = task->perf_event_ctxp[ctxn]; | |
3220 | if (likely(!ctx)) | |
3221 | continue; | |
3222 | ||
e5d1367f | 3223 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3224 | } |
d010b332 | 3225 | |
45ac1403 AH |
3226 | if (atomic_read(&nr_switch_events)) |
3227 | perf_event_switch(task, prev, true); | |
3228 | ||
ba532500 YZ |
3229 | if (__this_cpu_read(perf_sched_cb_usages)) |
3230 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3231 | } |
3232 | ||
abd50713 PZ |
3233 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3234 | { | |
3235 | u64 frequency = event->attr.sample_freq; | |
3236 | u64 sec = NSEC_PER_SEC; | |
3237 | u64 divisor, dividend; | |
3238 | ||
3239 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3240 | ||
3241 | count_fls = fls64(count); | |
3242 | nsec_fls = fls64(nsec); | |
3243 | frequency_fls = fls64(frequency); | |
3244 | sec_fls = 30; | |
3245 | ||
3246 | /* | |
3247 | * We got @count in @nsec, with a target of sample_freq HZ | |
3248 | * the target period becomes: | |
3249 | * | |
3250 | * @count * 10^9 | |
3251 | * period = ------------------- | |
3252 | * @nsec * sample_freq | |
3253 | * | |
3254 | */ | |
3255 | ||
3256 | /* | |
3257 | * Reduce accuracy by one bit such that @a and @b converge | |
3258 | * to a similar magnitude. | |
3259 | */ | |
fe4b04fa | 3260 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3261 | do { \ |
3262 | if (a##_fls > b##_fls) { \ | |
3263 | a >>= 1; \ | |
3264 | a##_fls--; \ | |
3265 | } else { \ | |
3266 | b >>= 1; \ | |
3267 | b##_fls--; \ | |
3268 | } \ | |
3269 | } while (0) | |
3270 | ||
3271 | /* | |
3272 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3273 | * the other, so that finally we can do a u64/u64 division. | |
3274 | */ | |
3275 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3276 | REDUCE_FLS(nsec, frequency); | |
3277 | REDUCE_FLS(sec, count); | |
3278 | } | |
3279 | ||
3280 | if (count_fls + sec_fls > 64) { | |
3281 | divisor = nsec * frequency; | |
3282 | ||
3283 | while (count_fls + sec_fls > 64) { | |
3284 | REDUCE_FLS(count, sec); | |
3285 | divisor >>= 1; | |
3286 | } | |
3287 | ||
3288 | dividend = count * sec; | |
3289 | } else { | |
3290 | dividend = count * sec; | |
3291 | ||
3292 | while (nsec_fls + frequency_fls > 64) { | |
3293 | REDUCE_FLS(nsec, frequency); | |
3294 | dividend >>= 1; | |
3295 | } | |
3296 | ||
3297 | divisor = nsec * frequency; | |
3298 | } | |
3299 | ||
f6ab91ad PZ |
3300 | if (!divisor) |
3301 | return dividend; | |
3302 | ||
abd50713 PZ |
3303 | return div64_u64(dividend, divisor); |
3304 | } | |
3305 | ||
e050e3f0 SE |
3306 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3307 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3308 | ||
f39d47ff | 3309 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3310 | { |
cdd6c482 | 3311 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3312 | s64 period, sample_period; |
bd2b5b12 PZ |
3313 | s64 delta; |
3314 | ||
abd50713 | 3315 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3316 | |
3317 | delta = (s64)(period - hwc->sample_period); | |
3318 | delta = (delta + 7) / 8; /* low pass filter */ | |
3319 | ||
3320 | sample_period = hwc->sample_period + delta; | |
3321 | ||
3322 | if (!sample_period) | |
3323 | sample_period = 1; | |
3324 | ||
bd2b5b12 | 3325 | hwc->sample_period = sample_period; |
abd50713 | 3326 | |
e7850595 | 3327 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3328 | if (disable) |
3329 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3330 | ||
e7850595 | 3331 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3332 | |
3333 | if (disable) | |
3334 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3335 | } |
bd2b5b12 PZ |
3336 | } |
3337 | ||
e050e3f0 SE |
3338 | /* |
3339 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3340 | * events. At the same time, make sure, having freq events does not change | |
3341 | * the rate of unthrottling as that would introduce bias. | |
3342 | */ | |
3343 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3344 | int needs_unthr) | |
60db5e09 | 3345 | { |
cdd6c482 IM |
3346 | struct perf_event *event; |
3347 | struct hw_perf_event *hwc; | |
e050e3f0 | 3348 | u64 now, period = TICK_NSEC; |
abd50713 | 3349 | s64 delta; |
60db5e09 | 3350 | |
e050e3f0 SE |
3351 | /* |
3352 | * only need to iterate over all events iff: | |
3353 | * - context have events in frequency mode (needs freq adjust) | |
3354 | * - there are events to unthrottle on this cpu | |
3355 | */ | |
3356 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3357 | return; |
3358 | ||
e050e3f0 | 3359 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3360 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3361 | |
03541f8b | 3362 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3363 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3364 | continue; |
3365 | ||
5632ab12 | 3366 | if (!event_filter_match(event)) |
5d27c23d PZ |
3367 | continue; |
3368 | ||
44377277 AS |
3369 | perf_pmu_disable(event->pmu); |
3370 | ||
cdd6c482 | 3371 | hwc = &event->hw; |
6a24ed6c | 3372 | |
ae23bff1 | 3373 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3374 | hwc->interrupts = 0; |
cdd6c482 | 3375 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3376 | event->pmu->start(event, 0); |
a78ac325 PZ |
3377 | } |
3378 | ||
cdd6c482 | 3379 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3380 | goto next; |
60db5e09 | 3381 | |
e050e3f0 SE |
3382 | /* |
3383 | * stop the event and update event->count | |
3384 | */ | |
3385 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3386 | ||
e7850595 | 3387 | now = local64_read(&event->count); |
abd50713 PZ |
3388 | delta = now - hwc->freq_count_stamp; |
3389 | hwc->freq_count_stamp = now; | |
60db5e09 | 3390 | |
e050e3f0 SE |
3391 | /* |
3392 | * restart the event | |
3393 | * reload only if value has changed | |
f39d47ff SE |
3394 | * we have stopped the event so tell that |
3395 | * to perf_adjust_period() to avoid stopping it | |
3396 | * twice. | |
e050e3f0 | 3397 | */ |
abd50713 | 3398 | if (delta > 0) |
f39d47ff | 3399 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3400 | |
3401 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3402 | next: |
3403 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3404 | } |
e050e3f0 | 3405 | |
f39d47ff | 3406 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3407 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3408 | } |
3409 | ||
235c7fc7 | 3410 | /* |
cdd6c482 | 3411 | * Round-robin a context's events: |
235c7fc7 | 3412 | */ |
cdd6c482 | 3413 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3414 | { |
dddd3379 TG |
3415 | /* |
3416 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3417 | * disabled by the inheritance code. | |
3418 | */ | |
3419 | if (!ctx->rotate_disable) | |
3420 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3421 | } |
3422 | ||
9e630205 | 3423 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3424 | { |
8dc85d54 | 3425 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3426 | int rotate = 0; |
7fc23a53 | 3427 | |
b5ab4cd5 | 3428 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3429 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3430 | rotate = 1; | |
3431 | } | |
235c7fc7 | 3432 | |
8dc85d54 | 3433 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3434 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3435 | if (ctx->nr_events != ctx->nr_active) |
3436 | rotate = 1; | |
3437 | } | |
9717e6cd | 3438 | |
e050e3f0 | 3439 | if (!rotate) |
0f5a2601 PZ |
3440 | goto done; |
3441 | ||
facc4307 | 3442 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3443 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3444 | |
e050e3f0 SE |
3445 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3446 | if (ctx) | |
3447 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3448 | |
e050e3f0 SE |
3449 | rotate_ctx(&cpuctx->ctx); |
3450 | if (ctx) | |
3451 | rotate_ctx(ctx); | |
235c7fc7 | 3452 | |
e050e3f0 | 3453 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3454 | |
0f5a2601 PZ |
3455 | perf_pmu_enable(cpuctx->ctx.pmu); |
3456 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3457 | done: |
9e630205 SE |
3458 | |
3459 | return rotate; | |
e9d2b064 PZ |
3460 | } |
3461 | ||
3462 | void perf_event_task_tick(void) | |
3463 | { | |
2fde4f94 MR |
3464 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3465 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3466 | int throttled; |
b5ab4cd5 | 3467 | |
e9d2b064 PZ |
3468 | WARN_ON(!irqs_disabled()); |
3469 | ||
e050e3f0 SE |
3470 | __this_cpu_inc(perf_throttled_seq); |
3471 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3472 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3473 | |
2fde4f94 | 3474 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3475 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3476 | } |
3477 | ||
889ff015 FW |
3478 | static int event_enable_on_exec(struct perf_event *event, |
3479 | struct perf_event_context *ctx) | |
3480 | { | |
3481 | if (!event->attr.enable_on_exec) | |
3482 | return 0; | |
3483 | ||
3484 | event->attr.enable_on_exec = 0; | |
3485 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3486 | return 0; | |
3487 | ||
1d9b482e | 3488 | __perf_event_mark_enabled(event); |
889ff015 FW |
3489 | |
3490 | return 1; | |
3491 | } | |
3492 | ||
57e7986e | 3493 | /* |
cdd6c482 | 3494 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3495 | * This expects task == current. |
3496 | */ | |
c1274499 | 3497 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3498 | { |
c1274499 | 3499 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3500 | enum event_type_t event_type = 0; |
3e349507 | 3501 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3502 | struct perf_event *event; |
57e7986e PM |
3503 | unsigned long flags; |
3504 | int enabled = 0; | |
3505 | ||
3506 | local_irq_save(flags); | |
c1274499 | 3507 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3508 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3509 | goto out; |
3510 | ||
3e349507 PZ |
3511 | cpuctx = __get_cpu_context(ctx); |
3512 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3513 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3514 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3515 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3516 | event_type |= get_event_type(event); |
3517 | } | |
57e7986e PM |
3518 | |
3519 | /* | |
3e349507 | 3520 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3521 | */ |
3e349507 | 3522 | if (enabled) { |
211de6eb | 3523 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3524 | ctx_resched(cpuctx, ctx, event_type); |
3e349507 PZ |
3525 | } |
3526 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3527 | |
9ed6060d | 3528 | out: |
57e7986e | 3529 | local_irq_restore(flags); |
211de6eb PZ |
3530 | |
3531 | if (clone_ctx) | |
3532 | put_ctx(clone_ctx); | |
57e7986e PM |
3533 | } |
3534 | ||
0492d4c5 PZ |
3535 | struct perf_read_data { |
3536 | struct perf_event *event; | |
3537 | bool group; | |
7d88962e | 3538 | int ret; |
0492d4c5 PZ |
3539 | }; |
3540 | ||
d6a2f903 DCC |
3541 | static int find_cpu_to_read(struct perf_event *event, int local_cpu) |
3542 | { | |
3543 | int event_cpu = event->oncpu; | |
3544 | u16 local_pkg, event_pkg; | |
3545 | ||
3546 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
3547 | event_pkg = topology_physical_package_id(event_cpu); | |
3548 | local_pkg = topology_physical_package_id(local_cpu); | |
3549 | ||
3550 | if (event_pkg == local_pkg) | |
3551 | return local_cpu; | |
3552 | } | |
3553 | ||
3554 | return event_cpu; | |
3555 | } | |
3556 | ||
0793a61d | 3557 | /* |
cdd6c482 | 3558 | * Cross CPU call to read the hardware event |
0793a61d | 3559 | */ |
cdd6c482 | 3560 | static void __perf_event_read(void *info) |
0793a61d | 3561 | { |
0492d4c5 PZ |
3562 | struct perf_read_data *data = info; |
3563 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3564 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3565 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3566 | struct pmu *pmu = event->pmu; |
621a01ea | 3567 | |
e1ac3614 PM |
3568 | /* |
3569 | * If this is a task context, we need to check whether it is | |
3570 | * the current task context of this cpu. If not it has been | |
3571 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3572 | * event->count would have been updated to a recent sample |
3573 | * when the event was scheduled out. | |
e1ac3614 PM |
3574 | */ |
3575 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3576 | return; | |
3577 | ||
e625cce1 | 3578 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3579 | if (ctx->is_active) { |
542e72fc | 3580 | update_context_time(ctx); |
e5d1367f SE |
3581 | update_cgrp_time_from_event(event); |
3582 | } | |
0492d4c5 | 3583 | |
cdd6c482 | 3584 | update_event_times(event); |
4a00c16e SB |
3585 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3586 | goto unlock; | |
0492d4c5 | 3587 | |
4a00c16e SB |
3588 | if (!data->group) { |
3589 | pmu->read(event); | |
3590 | data->ret = 0; | |
0492d4c5 | 3591 | goto unlock; |
4a00c16e SB |
3592 | } |
3593 | ||
3594 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3595 | ||
3596 | pmu->read(event); | |
0492d4c5 PZ |
3597 | |
3598 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3599 | update_event_times(sub); | |
4a00c16e SB |
3600 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3601 | /* | |
3602 | * Use sibling's PMU rather than @event's since | |
3603 | * sibling could be on different (eg: software) PMU. | |
3604 | */ | |
0492d4c5 | 3605 | sub->pmu->read(sub); |
4a00c16e | 3606 | } |
0492d4c5 | 3607 | } |
4a00c16e SB |
3608 | |
3609 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3610 | |
3611 | unlock: | |
e625cce1 | 3612 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3613 | } |
3614 | ||
b5e58793 PZ |
3615 | static inline u64 perf_event_count(struct perf_event *event) |
3616 | { | |
eacd3ecc MF |
3617 | if (event->pmu->count) |
3618 | return event->pmu->count(event); | |
3619 | ||
3620 | return __perf_event_count(event); | |
b5e58793 PZ |
3621 | } |
3622 | ||
ffe8690c KX |
3623 | /* |
3624 | * NMI-safe method to read a local event, that is an event that | |
3625 | * is: | |
3626 | * - either for the current task, or for this CPU | |
3627 | * - does not have inherit set, for inherited task events | |
3628 | * will not be local and we cannot read them atomically | |
3629 | * - must not have a pmu::count method | |
3630 | */ | |
3631 | u64 perf_event_read_local(struct perf_event *event) | |
3632 | { | |
3633 | unsigned long flags; | |
3634 | u64 val; | |
3635 | ||
3636 | /* | |
3637 | * Disabling interrupts avoids all counter scheduling (context | |
3638 | * switches, timer based rotation and IPIs). | |
3639 | */ | |
3640 | local_irq_save(flags); | |
3641 | ||
3642 | /* If this is a per-task event, it must be for current */ | |
3643 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3644 | event->hw.target != current); | |
3645 | ||
3646 | /* If this is a per-CPU event, it must be for this CPU */ | |
3647 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3648 | event->cpu != smp_processor_id()); | |
3649 | ||
3650 | /* | |
3651 | * It must not be an event with inherit set, we cannot read | |
3652 | * all child counters from atomic context. | |
3653 | */ | |
3654 | WARN_ON_ONCE(event->attr.inherit); | |
3655 | ||
3656 | /* | |
3657 | * It must not have a pmu::count method, those are not | |
3658 | * NMI safe. | |
3659 | */ | |
3660 | WARN_ON_ONCE(event->pmu->count); | |
3661 | ||
3662 | /* | |
3663 | * If the event is currently on this CPU, its either a per-task event, | |
3664 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3665 | * oncpu == -1). | |
3666 | */ | |
3667 | if (event->oncpu == smp_processor_id()) | |
3668 | event->pmu->read(event); | |
3669 | ||
3670 | val = local64_read(&event->count); | |
3671 | local_irq_restore(flags); | |
3672 | ||
3673 | return val; | |
3674 | } | |
3675 | ||
7d88962e | 3676 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3677 | { |
d6a2f903 | 3678 | int ret = 0, cpu_to_read, local_cpu; |
7d88962e | 3679 | |
0793a61d | 3680 | /* |
cdd6c482 IM |
3681 | * If event is enabled and currently active on a CPU, update the |
3682 | * value in the event structure: | |
0793a61d | 3683 | */ |
cdd6c482 | 3684 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3685 | struct perf_read_data data = { |
3686 | .event = event, | |
3687 | .group = group, | |
7d88962e | 3688 | .ret = 0, |
0492d4c5 | 3689 | }; |
d6a2f903 DCC |
3690 | |
3691 | local_cpu = get_cpu(); | |
3692 | cpu_to_read = find_cpu_to_read(event, local_cpu); | |
3693 | put_cpu(); | |
3694 | ||
58763148 PZ |
3695 | /* |
3696 | * Purposely ignore the smp_call_function_single() return | |
3697 | * value. | |
3698 | * | |
3699 | * If event->oncpu isn't a valid CPU it means the event got | |
3700 | * scheduled out and that will have updated the event count. | |
3701 | * | |
3702 | * Therefore, either way, we'll have an up-to-date event count | |
3703 | * after this. | |
3704 | */ | |
2cc53841 | 3705 | (void)smp_call_function_single(cpu_to_read, __perf_event_read, &data, 1); |
58763148 | 3706 | ret = data.ret; |
cdd6c482 | 3707 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3708 | struct perf_event_context *ctx = event->ctx; |
3709 | unsigned long flags; | |
3710 | ||
e625cce1 | 3711 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3712 | /* |
3713 | * may read while context is not active | |
3714 | * (e.g., thread is blocked), in that case | |
3715 | * we cannot update context time | |
3716 | */ | |
e5d1367f | 3717 | if (ctx->is_active) { |
c530ccd9 | 3718 | update_context_time(ctx); |
e5d1367f SE |
3719 | update_cgrp_time_from_event(event); |
3720 | } | |
0492d4c5 PZ |
3721 | if (group) |
3722 | update_group_times(event); | |
3723 | else | |
3724 | update_event_times(event); | |
e625cce1 | 3725 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3726 | } |
7d88962e SB |
3727 | |
3728 | return ret; | |
0793a61d TG |
3729 | } |
3730 | ||
a63eaf34 | 3731 | /* |
cdd6c482 | 3732 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3733 | */ |
eb184479 | 3734 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3735 | { |
e625cce1 | 3736 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3737 | mutex_init(&ctx->mutex); |
2fde4f94 | 3738 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3739 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3740 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3741 | INIT_LIST_HEAD(&ctx->event_list); |
3742 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3743 | } |
3744 | ||
3745 | static struct perf_event_context * | |
3746 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3747 | { | |
3748 | struct perf_event_context *ctx; | |
3749 | ||
3750 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3751 | if (!ctx) | |
3752 | return NULL; | |
3753 | ||
3754 | __perf_event_init_context(ctx); | |
3755 | if (task) { | |
3756 | ctx->task = task; | |
3757 | get_task_struct(task); | |
0793a61d | 3758 | } |
eb184479 PZ |
3759 | ctx->pmu = pmu; |
3760 | ||
3761 | return ctx; | |
a63eaf34 PM |
3762 | } |
3763 | ||
2ebd4ffb MH |
3764 | static struct task_struct * |
3765 | find_lively_task_by_vpid(pid_t vpid) | |
3766 | { | |
3767 | struct task_struct *task; | |
0793a61d TG |
3768 | |
3769 | rcu_read_lock(); | |
2ebd4ffb | 3770 | if (!vpid) |
0793a61d TG |
3771 | task = current; |
3772 | else | |
2ebd4ffb | 3773 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3774 | if (task) |
3775 | get_task_struct(task); | |
3776 | rcu_read_unlock(); | |
3777 | ||
3778 | if (!task) | |
3779 | return ERR_PTR(-ESRCH); | |
3780 | ||
2ebd4ffb | 3781 | return task; |
2ebd4ffb MH |
3782 | } |
3783 | ||
fe4b04fa PZ |
3784 | /* |
3785 | * Returns a matching context with refcount and pincount. | |
3786 | */ | |
108b02cf | 3787 | static struct perf_event_context * |
4af57ef2 YZ |
3788 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3789 | struct perf_event *event) | |
0793a61d | 3790 | { |
211de6eb | 3791 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3792 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3793 | void *task_ctx_data = NULL; |
25346b93 | 3794 | unsigned long flags; |
8dc85d54 | 3795 | int ctxn, err; |
4af57ef2 | 3796 | int cpu = event->cpu; |
0793a61d | 3797 | |
22a4ec72 | 3798 | if (!task) { |
cdd6c482 | 3799 | /* Must be root to operate on a CPU event: */ |
0764771d | 3800 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3801 | return ERR_PTR(-EACCES); |
3802 | ||
0793a61d | 3803 | /* |
cdd6c482 | 3804 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3805 | * offline CPU and activate it when the CPU comes up, but |
3806 | * that's for later. | |
3807 | */ | |
f6325e30 | 3808 | if (!cpu_online(cpu)) |
0793a61d TG |
3809 | return ERR_PTR(-ENODEV); |
3810 | ||
108b02cf | 3811 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3812 | ctx = &cpuctx->ctx; |
c93f7669 | 3813 | get_ctx(ctx); |
fe4b04fa | 3814 | ++ctx->pin_count; |
0793a61d | 3815 | |
0793a61d TG |
3816 | return ctx; |
3817 | } | |
3818 | ||
8dc85d54 PZ |
3819 | err = -EINVAL; |
3820 | ctxn = pmu->task_ctx_nr; | |
3821 | if (ctxn < 0) | |
3822 | goto errout; | |
3823 | ||
4af57ef2 YZ |
3824 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3825 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3826 | if (!task_ctx_data) { | |
3827 | err = -ENOMEM; | |
3828 | goto errout; | |
3829 | } | |
3830 | } | |
3831 | ||
9ed6060d | 3832 | retry: |
8dc85d54 | 3833 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3834 | if (ctx) { |
211de6eb | 3835 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3836 | ++ctx->pin_count; |
4af57ef2 YZ |
3837 | |
3838 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3839 | ctx->task_ctx_data = task_ctx_data; | |
3840 | task_ctx_data = NULL; | |
3841 | } | |
e625cce1 | 3842 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3843 | |
3844 | if (clone_ctx) | |
3845 | put_ctx(clone_ctx); | |
9137fb28 | 3846 | } else { |
eb184479 | 3847 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3848 | err = -ENOMEM; |
3849 | if (!ctx) | |
3850 | goto errout; | |
eb184479 | 3851 | |
4af57ef2 YZ |
3852 | if (task_ctx_data) { |
3853 | ctx->task_ctx_data = task_ctx_data; | |
3854 | task_ctx_data = NULL; | |
3855 | } | |
3856 | ||
dbe08d82 ON |
3857 | err = 0; |
3858 | mutex_lock(&task->perf_event_mutex); | |
3859 | /* | |
3860 | * If it has already passed perf_event_exit_task(). | |
3861 | * we must see PF_EXITING, it takes this mutex too. | |
3862 | */ | |
3863 | if (task->flags & PF_EXITING) | |
3864 | err = -ESRCH; | |
3865 | else if (task->perf_event_ctxp[ctxn]) | |
3866 | err = -EAGAIN; | |
fe4b04fa | 3867 | else { |
9137fb28 | 3868 | get_ctx(ctx); |
fe4b04fa | 3869 | ++ctx->pin_count; |
dbe08d82 | 3870 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3871 | } |
dbe08d82 ON |
3872 | mutex_unlock(&task->perf_event_mutex); |
3873 | ||
3874 | if (unlikely(err)) { | |
9137fb28 | 3875 | put_ctx(ctx); |
dbe08d82 ON |
3876 | |
3877 | if (err == -EAGAIN) | |
3878 | goto retry; | |
3879 | goto errout; | |
a63eaf34 PM |
3880 | } |
3881 | } | |
3882 | ||
4af57ef2 | 3883 | kfree(task_ctx_data); |
0793a61d | 3884 | return ctx; |
c93f7669 | 3885 | |
9ed6060d | 3886 | errout: |
4af57ef2 | 3887 | kfree(task_ctx_data); |
c93f7669 | 3888 | return ERR_PTR(err); |
0793a61d TG |
3889 | } |
3890 | ||
6fb2915d | 3891 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3892 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3893 | |
cdd6c482 | 3894 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3895 | { |
cdd6c482 | 3896 | struct perf_event *event; |
592903cd | 3897 | |
cdd6c482 IM |
3898 | event = container_of(head, struct perf_event, rcu_head); |
3899 | if (event->ns) | |
3900 | put_pid_ns(event->ns); | |
6fb2915d | 3901 | perf_event_free_filter(event); |
cdd6c482 | 3902 | kfree(event); |
592903cd PZ |
3903 | } |
3904 | ||
b69cf536 PZ |
3905 | static void ring_buffer_attach(struct perf_event *event, |
3906 | struct ring_buffer *rb); | |
925d519a | 3907 | |
f2fb6bef KL |
3908 | static void detach_sb_event(struct perf_event *event) |
3909 | { | |
3910 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3911 | ||
3912 | raw_spin_lock(&pel->lock); | |
3913 | list_del_rcu(&event->sb_list); | |
3914 | raw_spin_unlock(&pel->lock); | |
3915 | } | |
3916 | ||
a4f144eb | 3917 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3918 | { |
a4f144eb DCC |
3919 | struct perf_event_attr *attr = &event->attr; |
3920 | ||
f2fb6bef | 3921 | if (event->parent) |
a4f144eb | 3922 | return false; |
f2fb6bef KL |
3923 | |
3924 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3925 | return false; |
f2fb6bef | 3926 | |
a4f144eb DCC |
3927 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3928 | attr->comm || attr->comm_exec || | |
3929 | attr->task || | |
3930 | attr->context_switch) | |
3931 | return true; | |
3932 | return false; | |
3933 | } | |
3934 | ||
3935 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3936 | { | |
3937 | if (is_sb_event(event)) | |
3938 | detach_sb_event(event); | |
f2fb6bef KL |
3939 | } |
3940 | ||
4beb31f3 | 3941 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3942 | { |
4beb31f3 FW |
3943 | if (event->parent) |
3944 | return; | |
3945 | ||
4beb31f3 FW |
3946 | if (is_cgroup_event(event)) |
3947 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3948 | } | |
925d519a | 3949 | |
555e0c1e FW |
3950 | #ifdef CONFIG_NO_HZ_FULL |
3951 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3952 | #endif | |
3953 | ||
3954 | static void unaccount_freq_event_nohz(void) | |
3955 | { | |
3956 | #ifdef CONFIG_NO_HZ_FULL | |
3957 | spin_lock(&nr_freq_lock); | |
3958 | if (atomic_dec_and_test(&nr_freq_events)) | |
3959 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3960 | spin_unlock(&nr_freq_lock); | |
3961 | #endif | |
3962 | } | |
3963 | ||
3964 | static void unaccount_freq_event(void) | |
3965 | { | |
3966 | if (tick_nohz_full_enabled()) | |
3967 | unaccount_freq_event_nohz(); | |
3968 | else | |
3969 | atomic_dec(&nr_freq_events); | |
3970 | } | |
3971 | ||
4beb31f3 FW |
3972 | static void unaccount_event(struct perf_event *event) |
3973 | { | |
25432ae9 PZ |
3974 | bool dec = false; |
3975 | ||
4beb31f3 FW |
3976 | if (event->parent) |
3977 | return; | |
3978 | ||
3979 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3980 | dec = true; |
4beb31f3 FW |
3981 | if (event->attr.mmap || event->attr.mmap_data) |
3982 | atomic_dec(&nr_mmap_events); | |
3983 | if (event->attr.comm) | |
3984 | atomic_dec(&nr_comm_events); | |
3985 | if (event->attr.task) | |
3986 | atomic_dec(&nr_task_events); | |
948b26b6 | 3987 | if (event->attr.freq) |
555e0c1e | 3988 | unaccount_freq_event(); |
45ac1403 | 3989 | if (event->attr.context_switch) { |
25432ae9 | 3990 | dec = true; |
45ac1403 AH |
3991 | atomic_dec(&nr_switch_events); |
3992 | } | |
4beb31f3 | 3993 | if (is_cgroup_event(event)) |
25432ae9 | 3994 | dec = true; |
4beb31f3 | 3995 | if (has_branch_stack(event)) |
25432ae9 PZ |
3996 | dec = true; |
3997 | ||
9107c89e PZ |
3998 | if (dec) { |
3999 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4000 | schedule_delayed_work(&perf_sched_work, HZ); | |
4001 | } | |
4beb31f3 FW |
4002 | |
4003 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4004 | |
4005 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4006 | } |
925d519a | 4007 | |
9107c89e PZ |
4008 | static void perf_sched_delayed(struct work_struct *work) |
4009 | { | |
4010 | mutex_lock(&perf_sched_mutex); | |
4011 | if (atomic_dec_and_test(&perf_sched_count)) | |
4012 | static_branch_disable(&perf_sched_events); | |
4013 | mutex_unlock(&perf_sched_mutex); | |
4014 | } | |
4015 | ||
bed5b25a AS |
4016 | /* |
4017 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4018 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4019 | * at a time, so we disallow creating events that might conflict, namely: | |
4020 | * | |
4021 | * 1) cpu-wide events in the presence of per-task events, | |
4022 | * 2) per-task events in the presence of cpu-wide events, | |
4023 | * 3) two matching events on the same context. | |
4024 | * | |
4025 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4026 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4027 | */ |
4028 | static int exclusive_event_init(struct perf_event *event) | |
4029 | { | |
4030 | struct pmu *pmu = event->pmu; | |
4031 | ||
4032 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4033 | return 0; | |
4034 | ||
4035 | /* | |
4036 | * Prevent co-existence of per-task and cpu-wide events on the | |
4037 | * same exclusive pmu. | |
4038 | * | |
4039 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4040 | * events on this "exclusive" pmu, positive means there are | |
4041 | * per-task events. | |
4042 | * | |
4043 | * Since this is called in perf_event_alloc() path, event::ctx | |
4044 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4045 | * to mean "per-task event", because unlike other attach states it | |
4046 | * never gets cleared. | |
4047 | */ | |
4048 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4049 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4050 | return -EBUSY; | |
4051 | } else { | |
4052 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4053 | return -EBUSY; | |
4054 | } | |
4055 | ||
4056 | return 0; | |
4057 | } | |
4058 | ||
4059 | static void exclusive_event_destroy(struct perf_event *event) | |
4060 | { | |
4061 | struct pmu *pmu = event->pmu; | |
4062 | ||
4063 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4064 | return; | |
4065 | ||
4066 | /* see comment in exclusive_event_init() */ | |
4067 | if (event->attach_state & PERF_ATTACH_TASK) | |
4068 | atomic_dec(&pmu->exclusive_cnt); | |
4069 | else | |
4070 | atomic_inc(&pmu->exclusive_cnt); | |
4071 | } | |
4072 | ||
4073 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4074 | { | |
3bf6215a | 4075 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4076 | (e1->cpu == e2->cpu || |
4077 | e1->cpu == -1 || | |
4078 | e2->cpu == -1)) | |
4079 | return true; | |
4080 | return false; | |
4081 | } | |
4082 | ||
4083 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4084 | static bool exclusive_event_installable(struct perf_event *event, | |
4085 | struct perf_event_context *ctx) | |
4086 | { | |
4087 | struct perf_event *iter_event; | |
4088 | struct pmu *pmu = event->pmu; | |
4089 | ||
4090 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4091 | return true; | |
4092 | ||
4093 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4094 | if (exclusive_event_match(iter_event, event)) | |
4095 | return false; | |
4096 | } | |
4097 | ||
4098 | return true; | |
4099 | } | |
4100 | ||
375637bc AS |
4101 | static void perf_addr_filters_splice(struct perf_event *event, |
4102 | struct list_head *head); | |
4103 | ||
683ede43 | 4104 | static void _free_event(struct perf_event *event) |
f1600952 | 4105 | { |
e360adbe | 4106 | irq_work_sync(&event->pending); |
925d519a | 4107 | |
4beb31f3 | 4108 | unaccount_event(event); |
9ee318a7 | 4109 | |
76369139 | 4110 | if (event->rb) { |
9bb5d40c PZ |
4111 | /* |
4112 | * Can happen when we close an event with re-directed output. | |
4113 | * | |
4114 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4115 | * over us; possibly making our ring_buffer_put() the last. | |
4116 | */ | |
4117 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4118 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4119 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4120 | } |
4121 | ||
e5d1367f SE |
4122 | if (is_cgroup_event(event)) |
4123 | perf_detach_cgroup(event); | |
4124 | ||
a0733e69 PZ |
4125 | if (!event->parent) { |
4126 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4127 | put_callchain_buffers(); | |
4128 | } | |
4129 | ||
4130 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4131 | perf_addr_filters_splice(event, NULL); |
4132 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4133 | |
4134 | if (event->destroy) | |
4135 | event->destroy(event); | |
4136 | ||
4137 | if (event->ctx) | |
4138 | put_ctx(event->ctx); | |
4139 | ||
62a92c8f AS |
4140 | exclusive_event_destroy(event); |
4141 | module_put(event->pmu->module); | |
a0733e69 PZ |
4142 | |
4143 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4144 | } |
4145 | ||
683ede43 PZ |
4146 | /* |
4147 | * Used to free events which have a known refcount of 1, such as in error paths | |
4148 | * where the event isn't exposed yet and inherited events. | |
4149 | */ | |
4150 | static void free_event(struct perf_event *event) | |
0793a61d | 4151 | { |
683ede43 PZ |
4152 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4153 | "unexpected event refcount: %ld; ptr=%p\n", | |
4154 | atomic_long_read(&event->refcount), event)) { | |
4155 | /* leak to avoid use-after-free */ | |
4156 | return; | |
4157 | } | |
0793a61d | 4158 | |
683ede43 | 4159 | _free_event(event); |
0793a61d TG |
4160 | } |
4161 | ||
a66a3052 | 4162 | /* |
f8697762 | 4163 | * Remove user event from the owner task. |
a66a3052 | 4164 | */ |
f8697762 | 4165 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4166 | { |
8882135b | 4167 | struct task_struct *owner; |
fb0459d7 | 4168 | |
8882135b | 4169 | rcu_read_lock(); |
8882135b | 4170 | /* |
f47c02c0 PZ |
4171 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4172 | * observe !owner it means the list deletion is complete and we can | |
4173 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4174 | * owner->perf_event_mutex. |
4175 | */ | |
f47c02c0 | 4176 | owner = lockless_dereference(event->owner); |
8882135b PZ |
4177 | if (owner) { |
4178 | /* | |
4179 | * Since delayed_put_task_struct() also drops the last | |
4180 | * task reference we can safely take a new reference | |
4181 | * while holding the rcu_read_lock(). | |
4182 | */ | |
4183 | get_task_struct(owner); | |
4184 | } | |
4185 | rcu_read_unlock(); | |
4186 | ||
4187 | if (owner) { | |
f63a8daa PZ |
4188 | /* |
4189 | * If we're here through perf_event_exit_task() we're already | |
4190 | * holding ctx->mutex which would be an inversion wrt. the | |
4191 | * normal lock order. | |
4192 | * | |
4193 | * However we can safely take this lock because its the child | |
4194 | * ctx->mutex. | |
4195 | */ | |
4196 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4197 | ||
8882135b PZ |
4198 | /* |
4199 | * We have to re-check the event->owner field, if it is cleared | |
4200 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4201 | * ensured they're done, and we can proceed with freeing the | |
4202 | * event. | |
4203 | */ | |
f47c02c0 | 4204 | if (event->owner) { |
8882135b | 4205 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4206 | smp_store_release(&event->owner, NULL); |
4207 | } | |
8882135b PZ |
4208 | mutex_unlock(&owner->perf_event_mutex); |
4209 | put_task_struct(owner); | |
4210 | } | |
f8697762 JO |
4211 | } |
4212 | ||
f8697762 JO |
4213 | static void put_event(struct perf_event *event) |
4214 | { | |
f8697762 JO |
4215 | if (!atomic_long_dec_and_test(&event->refcount)) |
4216 | return; | |
4217 | ||
c6e5b732 PZ |
4218 | _free_event(event); |
4219 | } | |
4220 | ||
4221 | /* | |
4222 | * Kill an event dead; while event:refcount will preserve the event | |
4223 | * object, it will not preserve its functionality. Once the last 'user' | |
4224 | * gives up the object, we'll destroy the thing. | |
4225 | */ | |
4226 | int perf_event_release_kernel(struct perf_event *event) | |
4227 | { | |
a4f4bb6d | 4228 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4229 | struct perf_event *child, *tmp; |
4230 | ||
a4f4bb6d PZ |
4231 | /* |
4232 | * If we got here through err_file: fput(event_file); we will not have | |
4233 | * attached to a context yet. | |
4234 | */ | |
4235 | if (!ctx) { | |
4236 | WARN_ON_ONCE(event->attach_state & | |
4237 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4238 | goto no_ctx; | |
4239 | } | |
4240 | ||
f8697762 JO |
4241 | if (!is_kernel_event(event)) |
4242 | perf_remove_from_owner(event); | |
8882135b | 4243 | |
5fa7c8ec | 4244 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4245 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4246 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4247 | |
a69b0ca4 | 4248 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4249 | /* |
a69b0ca4 PZ |
4250 | * Mark this even as STATE_DEAD, there is no external reference to it |
4251 | * anymore. | |
683ede43 | 4252 | * |
a69b0ca4 PZ |
4253 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4254 | * also see this, most importantly inherit_event() which will avoid | |
4255 | * placing more children on the list. | |
683ede43 | 4256 | * |
c6e5b732 PZ |
4257 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4258 | * child events. | |
683ede43 | 4259 | */ |
a69b0ca4 PZ |
4260 | event->state = PERF_EVENT_STATE_DEAD; |
4261 | raw_spin_unlock_irq(&ctx->lock); | |
4262 | ||
4263 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4264 | |
c6e5b732 PZ |
4265 | again: |
4266 | mutex_lock(&event->child_mutex); | |
4267 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4268 | |
c6e5b732 PZ |
4269 | /* |
4270 | * Cannot change, child events are not migrated, see the | |
4271 | * comment with perf_event_ctx_lock_nested(). | |
4272 | */ | |
4273 | ctx = lockless_dereference(child->ctx); | |
4274 | /* | |
4275 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4276 | * through hoops. We start by grabbing a reference on the ctx. | |
4277 | * | |
4278 | * Since the event cannot get freed while we hold the | |
4279 | * child_mutex, the context must also exist and have a !0 | |
4280 | * reference count. | |
4281 | */ | |
4282 | get_ctx(ctx); | |
4283 | ||
4284 | /* | |
4285 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4286 | * acquire ctx::mutex without fear of it going away. Then we | |
4287 | * can re-acquire child_mutex. | |
4288 | */ | |
4289 | mutex_unlock(&event->child_mutex); | |
4290 | mutex_lock(&ctx->mutex); | |
4291 | mutex_lock(&event->child_mutex); | |
4292 | ||
4293 | /* | |
4294 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4295 | * state, if child is still the first entry, it didn't get freed | |
4296 | * and we can continue doing so. | |
4297 | */ | |
4298 | tmp = list_first_entry_or_null(&event->child_list, | |
4299 | struct perf_event, child_list); | |
4300 | if (tmp == child) { | |
4301 | perf_remove_from_context(child, DETACH_GROUP); | |
4302 | list_del(&child->child_list); | |
4303 | free_event(child); | |
4304 | /* | |
4305 | * This matches the refcount bump in inherit_event(); | |
4306 | * this can't be the last reference. | |
4307 | */ | |
4308 | put_event(event); | |
4309 | } | |
4310 | ||
4311 | mutex_unlock(&event->child_mutex); | |
4312 | mutex_unlock(&ctx->mutex); | |
4313 | put_ctx(ctx); | |
4314 | goto again; | |
4315 | } | |
4316 | mutex_unlock(&event->child_mutex); | |
4317 | ||
a4f4bb6d PZ |
4318 | no_ctx: |
4319 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4320 | return 0; |
4321 | } | |
4322 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4323 | ||
8b10c5e2 PZ |
4324 | /* |
4325 | * Called when the last reference to the file is gone. | |
4326 | */ | |
a6fa941d AV |
4327 | static int perf_release(struct inode *inode, struct file *file) |
4328 | { | |
c6e5b732 | 4329 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4330 | return 0; |
fb0459d7 | 4331 | } |
fb0459d7 | 4332 | |
59ed446f | 4333 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4334 | { |
cdd6c482 | 4335 | struct perf_event *child; |
e53c0994 PZ |
4336 | u64 total = 0; |
4337 | ||
59ed446f PZ |
4338 | *enabled = 0; |
4339 | *running = 0; | |
4340 | ||
6f10581a | 4341 | mutex_lock(&event->child_mutex); |
01add3ea | 4342 | |
7d88962e | 4343 | (void)perf_event_read(event, false); |
01add3ea SB |
4344 | total += perf_event_count(event); |
4345 | ||
59ed446f PZ |
4346 | *enabled += event->total_time_enabled + |
4347 | atomic64_read(&event->child_total_time_enabled); | |
4348 | *running += event->total_time_running + | |
4349 | atomic64_read(&event->child_total_time_running); | |
4350 | ||
4351 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4352 | (void)perf_event_read(child, false); |
01add3ea | 4353 | total += perf_event_count(child); |
59ed446f PZ |
4354 | *enabled += child->total_time_enabled; |
4355 | *running += child->total_time_running; | |
4356 | } | |
6f10581a | 4357 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4358 | |
4359 | return total; | |
4360 | } | |
fb0459d7 | 4361 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4362 | |
7d88962e | 4363 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4364 | u64 read_format, u64 *values) |
3dab77fb | 4365 | { |
fa8c2693 PZ |
4366 | struct perf_event *sub; |
4367 | int n = 1; /* skip @nr */ | |
7d88962e | 4368 | int ret; |
f63a8daa | 4369 | |
7d88962e SB |
4370 | ret = perf_event_read(leader, true); |
4371 | if (ret) | |
4372 | return ret; | |
abf4868b | 4373 | |
fa8c2693 PZ |
4374 | /* |
4375 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4376 | * will be identical to those of the leader, so we only publish one | |
4377 | * set. | |
4378 | */ | |
4379 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4380 | values[n++] += leader->total_time_enabled + | |
4381 | atomic64_read(&leader->child_total_time_enabled); | |
4382 | } | |
3dab77fb | 4383 | |
fa8c2693 PZ |
4384 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4385 | values[n++] += leader->total_time_running + | |
4386 | atomic64_read(&leader->child_total_time_running); | |
4387 | } | |
4388 | ||
4389 | /* | |
4390 | * Write {count,id} tuples for every sibling. | |
4391 | */ | |
4392 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4393 | if (read_format & PERF_FORMAT_ID) |
4394 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4395 | |
fa8c2693 PZ |
4396 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4397 | values[n++] += perf_event_count(sub); | |
4398 | if (read_format & PERF_FORMAT_ID) | |
4399 | values[n++] = primary_event_id(sub); | |
4400 | } | |
7d88962e SB |
4401 | |
4402 | return 0; | |
fa8c2693 | 4403 | } |
3dab77fb | 4404 | |
fa8c2693 PZ |
4405 | static int perf_read_group(struct perf_event *event, |
4406 | u64 read_format, char __user *buf) | |
4407 | { | |
4408 | struct perf_event *leader = event->group_leader, *child; | |
4409 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4410 | int ret; |
fa8c2693 | 4411 | u64 *values; |
3dab77fb | 4412 | |
fa8c2693 | 4413 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4414 | |
fa8c2693 PZ |
4415 | values = kzalloc(event->read_size, GFP_KERNEL); |
4416 | if (!values) | |
4417 | return -ENOMEM; | |
3dab77fb | 4418 | |
fa8c2693 PZ |
4419 | values[0] = 1 + leader->nr_siblings; |
4420 | ||
4421 | /* | |
4422 | * By locking the child_mutex of the leader we effectively | |
4423 | * lock the child list of all siblings.. XXX explain how. | |
4424 | */ | |
4425 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4426 | |
7d88962e SB |
4427 | ret = __perf_read_group_add(leader, read_format, values); |
4428 | if (ret) | |
4429 | goto unlock; | |
4430 | ||
4431 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4432 | ret = __perf_read_group_add(child, read_format, values); | |
4433 | if (ret) | |
4434 | goto unlock; | |
4435 | } | |
abf4868b | 4436 | |
fa8c2693 | 4437 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4438 | |
7d88962e | 4439 | ret = event->read_size; |
fa8c2693 PZ |
4440 | if (copy_to_user(buf, values, event->read_size)) |
4441 | ret = -EFAULT; | |
7d88962e | 4442 | goto out; |
fa8c2693 | 4443 | |
7d88962e SB |
4444 | unlock: |
4445 | mutex_unlock(&leader->child_mutex); | |
4446 | out: | |
fa8c2693 | 4447 | kfree(values); |
abf4868b | 4448 | return ret; |
3dab77fb PZ |
4449 | } |
4450 | ||
b15f495b | 4451 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4452 | u64 read_format, char __user *buf) |
4453 | { | |
59ed446f | 4454 | u64 enabled, running; |
3dab77fb PZ |
4455 | u64 values[4]; |
4456 | int n = 0; | |
4457 | ||
59ed446f PZ |
4458 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4459 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4460 | values[n++] = enabled; | |
4461 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4462 | values[n++] = running; | |
3dab77fb | 4463 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4464 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4465 | |
4466 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4467 | return -EFAULT; | |
4468 | ||
4469 | return n * sizeof(u64); | |
4470 | } | |
4471 | ||
dc633982 JO |
4472 | static bool is_event_hup(struct perf_event *event) |
4473 | { | |
4474 | bool no_children; | |
4475 | ||
a69b0ca4 | 4476 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4477 | return false; |
4478 | ||
4479 | mutex_lock(&event->child_mutex); | |
4480 | no_children = list_empty(&event->child_list); | |
4481 | mutex_unlock(&event->child_mutex); | |
4482 | return no_children; | |
4483 | } | |
4484 | ||
0793a61d | 4485 | /* |
cdd6c482 | 4486 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4487 | */ |
4488 | static ssize_t | |
b15f495b | 4489 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4490 | { |
cdd6c482 | 4491 | u64 read_format = event->attr.read_format; |
3dab77fb | 4492 | int ret; |
0793a61d | 4493 | |
3b6f9e5c | 4494 | /* |
cdd6c482 | 4495 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4496 | * error state (i.e. because it was pinned but it couldn't be |
4497 | * scheduled on to the CPU at some point). | |
4498 | */ | |
cdd6c482 | 4499 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4500 | return 0; |
4501 | ||
c320c7b7 | 4502 | if (count < event->read_size) |
3dab77fb PZ |
4503 | return -ENOSPC; |
4504 | ||
cdd6c482 | 4505 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4506 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4507 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4508 | else |
b15f495b | 4509 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4510 | |
3dab77fb | 4511 | return ret; |
0793a61d TG |
4512 | } |
4513 | ||
0793a61d TG |
4514 | static ssize_t |
4515 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4516 | { | |
cdd6c482 | 4517 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4518 | struct perf_event_context *ctx; |
4519 | int ret; | |
0793a61d | 4520 | |
f63a8daa | 4521 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4522 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4523 | perf_event_ctx_unlock(event, ctx); |
4524 | ||
4525 | return ret; | |
0793a61d TG |
4526 | } |
4527 | ||
4528 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4529 | { | |
cdd6c482 | 4530 | struct perf_event *event = file->private_data; |
76369139 | 4531 | struct ring_buffer *rb; |
61b67684 | 4532 | unsigned int events = POLLHUP; |
c7138f37 | 4533 | |
e708d7ad | 4534 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4535 | |
dc633982 | 4536 | if (is_event_hup(event)) |
179033b3 | 4537 | return events; |
c7138f37 | 4538 | |
10c6db11 | 4539 | /* |
9bb5d40c PZ |
4540 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4541 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4542 | */ |
4543 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4544 | rb = event->rb; |
4545 | if (rb) | |
76369139 | 4546 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4547 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4548 | return events; |
4549 | } | |
4550 | ||
f63a8daa | 4551 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4552 | { |
7d88962e | 4553 | (void)perf_event_read(event, false); |
e7850595 | 4554 | local64_set(&event->count, 0); |
cdd6c482 | 4555 | perf_event_update_userpage(event); |
3df5edad PZ |
4556 | } |
4557 | ||
c93f7669 | 4558 | /* |
cdd6c482 IM |
4559 | * Holding the top-level event's child_mutex means that any |
4560 | * descendant process that has inherited this event will block | |
8ba289b8 | 4561 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4562 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4563 | */ |
cdd6c482 IM |
4564 | static void perf_event_for_each_child(struct perf_event *event, |
4565 | void (*func)(struct perf_event *)) | |
3df5edad | 4566 | { |
cdd6c482 | 4567 | struct perf_event *child; |
3df5edad | 4568 | |
cdd6c482 | 4569 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4570 | |
cdd6c482 IM |
4571 | mutex_lock(&event->child_mutex); |
4572 | func(event); | |
4573 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4574 | func(child); |
cdd6c482 | 4575 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4576 | } |
4577 | ||
cdd6c482 IM |
4578 | static void perf_event_for_each(struct perf_event *event, |
4579 | void (*func)(struct perf_event *)) | |
3df5edad | 4580 | { |
cdd6c482 IM |
4581 | struct perf_event_context *ctx = event->ctx; |
4582 | struct perf_event *sibling; | |
3df5edad | 4583 | |
f63a8daa PZ |
4584 | lockdep_assert_held(&ctx->mutex); |
4585 | ||
cdd6c482 | 4586 | event = event->group_leader; |
75f937f2 | 4587 | |
cdd6c482 | 4588 | perf_event_for_each_child(event, func); |
cdd6c482 | 4589 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4590 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4591 | } |
4592 | ||
fae3fde6 PZ |
4593 | static void __perf_event_period(struct perf_event *event, |
4594 | struct perf_cpu_context *cpuctx, | |
4595 | struct perf_event_context *ctx, | |
4596 | void *info) | |
c7999c6f | 4597 | { |
fae3fde6 | 4598 | u64 value = *((u64 *)info); |
c7999c6f | 4599 | bool active; |
08247e31 | 4600 | |
cdd6c482 | 4601 | if (event->attr.freq) { |
cdd6c482 | 4602 | event->attr.sample_freq = value; |
08247e31 | 4603 | } else { |
cdd6c482 IM |
4604 | event->attr.sample_period = value; |
4605 | event->hw.sample_period = value; | |
08247e31 | 4606 | } |
bad7192b PZ |
4607 | |
4608 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4609 | if (active) { | |
4610 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4611 | /* |
4612 | * We could be throttled; unthrottle now to avoid the tick | |
4613 | * trying to unthrottle while we already re-started the event. | |
4614 | */ | |
4615 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4616 | event->hw.interrupts = 0; | |
4617 | perf_log_throttle(event, 1); | |
4618 | } | |
bad7192b PZ |
4619 | event->pmu->stop(event, PERF_EF_UPDATE); |
4620 | } | |
4621 | ||
4622 | local64_set(&event->hw.period_left, 0); | |
4623 | ||
4624 | if (active) { | |
4625 | event->pmu->start(event, PERF_EF_RELOAD); | |
4626 | perf_pmu_enable(ctx->pmu); | |
4627 | } | |
c7999c6f PZ |
4628 | } |
4629 | ||
4630 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4631 | { | |
c7999c6f PZ |
4632 | u64 value; |
4633 | ||
4634 | if (!is_sampling_event(event)) | |
4635 | return -EINVAL; | |
4636 | ||
4637 | if (copy_from_user(&value, arg, sizeof(value))) | |
4638 | return -EFAULT; | |
4639 | ||
4640 | if (!value) | |
4641 | return -EINVAL; | |
4642 | ||
4643 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4644 | return -EINVAL; | |
4645 | ||
fae3fde6 | 4646 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4647 | |
c7999c6f | 4648 | return 0; |
08247e31 PZ |
4649 | } |
4650 | ||
ac9721f3 PZ |
4651 | static const struct file_operations perf_fops; |
4652 | ||
2903ff01 | 4653 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4654 | { |
2903ff01 AV |
4655 | struct fd f = fdget(fd); |
4656 | if (!f.file) | |
4657 | return -EBADF; | |
ac9721f3 | 4658 | |
2903ff01 AV |
4659 | if (f.file->f_op != &perf_fops) { |
4660 | fdput(f); | |
4661 | return -EBADF; | |
ac9721f3 | 4662 | } |
2903ff01 AV |
4663 | *p = f; |
4664 | return 0; | |
ac9721f3 PZ |
4665 | } |
4666 | ||
4667 | static int perf_event_set_output(struct perf_event *event, | |
4668 | struct perf_event *output_event); | |
6fb2915d | 4669 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4670 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4671 | |
f63a8daa | 4672 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4673 | { |
cdd6c482 | 4674 | void (*func)(struct perf_event *); |
3df5edad | 4675 | u32 flags = arg; |
d859e29f PM |
4676 | |
4677 | switch (cmd) { | |
cdd6c482 | 4678 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4679 | func = _perf_event_enable; |
d859e29f | 4680 | break; |
cdd6c482 | 4681 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4682 | func = _perf_event_disable; |
79f14641 | 4683 | break; |
cdd6c482 | 4684 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4685 | func = _perf_event_reset; |
6de6a7b9 | 4686 | break; |
3df5edad | 4687 | |
cdd6c482 | 4688 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4689 | return _perf_event_refresh(event, arg); |
08247e31 | 4690 | |
cdd6c482 IM |
4691 | case PERF_EVENT_IOC_PERIOD: |
4692 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4693 | |
cf4957f1 JO |
4694 | case PERF_EVENT_IOC_ID: |
4695 | { | |
4696 | u64 id = primary_event_id(event); | |
4697 | ||
4698 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4699 | return -EFAULT; | |
4700 | return 0; | |
4701 | } | |
4702 | ||
cdd6c482 | 4703 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4704 | { |
ac9721f3 | 4705 | int ret; |
ac9721f3 | 4706 | if (arg != -1) { |
2903ff01 AV |
4707 | struct perf_event *output_event; |
4708 | struct fd output; | |
4709 | ret = perf_fget_light(arg, &output); | |
4710 | if (ret) | |
4711 | return ret; | |
4712 | output_event = output.file->private_data; | |
4713 | ret = perf_event_set_output(event, output_event); | |
4714 | fdput(output); | |
4715 | } else { | |
4716 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4717 | } |
ac9721f3 PZ |
4718 | return ret; |
4719 | } | |
a4be7c27 | 4720 | |
6fb2915d LZ |
4721 | case PERF_EVENT_IOC_SET_FILTER: |
4722 | return perf_event_set_filter(event, (void __user *)arg); | |
4723 | ||
2541517c AS |
4724 | case PERF_EVENT_IOC_SET_BPF: |
4725 | return perf_event_set_bpf_prog(event, arg); | |
4726 | ||
86e7972f WN |
4727 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4728 | struct ring_buffer *rb; | |
4729 | ||
4730 | rcu_read_lock(); | |
4731 | rb = rcu_dereference(event->rb); | |
4732 | if (!rb || !rb->nr_pages) { | |
4733 | rcu_read_unlock(); | |
4734 | return -EINVAL; | |
4735 | } | |
4736 | rb_toggle_paused(rb, !!arg); | |
4737 | rcu_read_unlock(); | |
4738 | return 0; | |
4739 | } | |
d859e29f | 4740 | default: |
3df5edad | 4741 | return -ENOTTY; |
d859e29f | 4742 | } |
3df5edad PZ |
4743 | |
4744 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4745 | perf_event_for_each(event, func); |
3df5edad | 4746 | else |
cdd6c482 | 4747 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4748 | |
4749 | return 0; | |
d859e29f PM |
4750 | } |
4751 | ||
f63a8daa PZ |
4752 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4753 | { | |
4754 | struct perf_event *event = file->private_data; | |
4755 | struct perf_event_context *ctx; | |
4756 | long ret; | |
4757 | ||
4758 | ctx = perf_event_ctx_lock(event); | |
4759 | ret = _perf_ioctl(event, cmd, arg); | |
4760 | perf_event_ctx_unlock(event, ctx); | |
4761 | ||
4762 | return ret; | |
4763 | } | |
4764 | ||
b3f20785 PM |
4765 | #ifdef CONFIG_COMPAT |
4766 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4767 | unsigned long arg) | |
4768 | { | |
4769 | switch (_IOC_NR(cmd)) { | |
4770 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4771 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4772 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4773 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4774 | cmd &= ~IOCSIZE_MASK; | |
4775 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4776 | } | |
4777 | break; | |
4778 | } | |
4779 | return perf_ioctl(file, cmd, arg); | |
4780 | } | |
4781 | #else | |
4782 | # define perf_compat_ioctl NULL | |
4783 | #endif | |
4784 | ||
cdd6c482 | 4785 | int perf_event_task_enable(void) |
771d7cde | 4786 | { |
f63a8daa | 4787 | struct perf_event_context *ctx; |
cdd6c482 | 4788 | struct perf_event *event; |
771d7cde | 4789 | |
cdd6c482 | 4790 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4791 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4792 | ctx = perf_event_ctx_lock(event); | |
4793 | perf_event_for_each_child(event, _perf_event_enable); | |
4794 | perf_event_ctx_unlock(event, ctx); | |
4795 | } | |
cdd6c482 | 4796 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4797 | |
4798 | return 0; | |
4799 | } | |
4800 | ||
cdd6c482 | 4801 | int perf_event_task_disable(void) |
771d7cde | 4802 | { |
f63a8daa | 4803 | struct perf_event_context *ctx; |
cdd6c482 | 4804 | struct perf_event *event; |
771d7cde | 4805 | |
cdd6c482 | 4806 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4807 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4808 | ctx = perf_event_ctx_lock(event); | |
4809 | perf_event_for_each_child(event, _perf_event_disable); | |
4810 | perf_event_ctx_unlock(event, ctx); | |
4811 | } | |
cdd6c482 | 4812 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4813 | |
4814 | return 0; | |
4815 | } | |
4816 | ||
cdd6c482 | 4817 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4818 | { |
a4eaf7f1 PZ |
4819 | if (event->hw.state & PERF_HES_STOPPED) |
4820 | return 0; | |
4821 | ||
cdd6c482 | 4822 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4823 | return 0; |
4824 | ||
35edc2a5 | 4825 | return event->pmu->event_idx(event); |
194002b2 PZ |
4826 | } |
4827 | ||
c4794295 | 4828 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4829 | u64 *now, |
7f310a5d EM |
4830 | u64 *enabled, |
4831 | u64 *running) | |
c4794295 | 4832 | { |
e3f3541c | 4833 | u64 ctx_time; |
c4794295 | 4834 | |
e3f3541c PZ |
4835 | *now = perf_clock(); |
4836 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4837 | *enabled = ctx_time - event->tstamp_enabled; |
4838 | *running = ctx_time - event->tstamp_running; | |
4839 | } | |
4840 | ||
fa731587 PZ |
4841 | static void perf_event_init_userpage(struct perf_event *event) |
4842 | { | |
4843 | struct perf_event_mmap_page *userpg; | |
4844 | struct ring_buffer *rb; | |
4845 | ||
4846 | rcu_read_lock(); | |
4847 | rb = rcu_dereference(event->rb); | |
4848 | if (!rb) | |
4849 | goto unlock; | |
4850 | ||
4851 | userpg = rb->user_page; | |
4852 | ||
4853 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4854 | userpg->cap_bit0_is_deprecated = 1; | |
4855 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4856 | userpg->data_offset = PAGE_SIZE; |
4857 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4858 | |
4859 | unlock: | |
4860 | rcu_read_unlock(); | |
4861 | } | |
4862 | ||
c1317ec2 AL |
4863 | void __weak arch_perf_update_userpage( |
4864 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4865 | { |
4866 | } | |
4867 | ||
38ff667b PZ |
4868 | /* |
4869 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4870 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4871 | * code calls this from NMI context. | |
4872 | */ | |
cdd6c482 | 4873 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4874 | { |
cdd6c482 | 4875 | struct perf_event_mmap_page *userpg; |
76369139 | 4876 | struct ring_buffer *rb; |
e3f3541c | 4877 | u64 enabled, running, now; |
38ff667b PZ |
4878 | |
4879 | rcu_read_lock(); | |
5ec4c599 PZ |
4880 | rb = rcu_dereference(event->rb); |
4881 | if (!rb) | |
4882 | goto unlock; | |
4883 | ||
0d641208 EM |
4884 | /* |
4885 | * compute total_time_enabled, total_time_running | |
4886 | * based on snapshot values taken when the event | |
4887 | * was last scheduled in. | |
4888 | * | |
4889 | * we cannot simply called update_context_time() | |
4890 | * because of locking issue as we can be called in | |
4891 | * NMI context | |
4892 | */ | |
e3f3541c | 4893 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4894 | |
76369139 | 4895 | userpg = rb->user_page; |
7b732a75 PZ |
4896 | /* |
4897 | * Disable preemption so as to not let the corresponding user-space | |
4898 | * spin too long if we get preempted. | |
4899 | */ | |
4900 | preempt_disable(); | |
37d81828 | 4901 | ++userpg->lock; |
92f22a38 | 4902 | barrier(); |
cdd6c482 | 4903 | userpg->index = perf_event_index(event); |
b5e58793 | 4904 | userpg->offset = perf_event_count(event); |
365a4038 | 4905 | if (userpg->index) |
e7850595 | 4906 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4907 | |
0d641208 | 4908 | userpg->time_enabled = enabled + |
cdd6c482 | 4909 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4910 | |
0d641208 | 4911 | userpg->time_running = running + |
cdd6c482 | 4912 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4913 | |
c1317ec2 | 4914 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4915 | |
92f22a38 | 4916 | barrier(); |
37d81828 | 4917 | ++userpg->lock; |
7b732a75 | 4918 | preempt_enable(); |
38ff667b | 4919 | unlock: |
7b732a75 | 4920 | rcu_read_unlock(); |
37d81828 PM |
4921 | } |
4922 | ||
906010b2 PZ |
4923 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4924 | { | |
4925 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4926 | struct ring_buffer *rb; |
906010b2 PZ |
4927 | int ret = VM_FAULT_SIGBUS; |
4928 | ||
4929 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4930 | if (vmf->pgoff == 0) | |
4931 | ret = 0; | |
4932 | return ret; | |
4933 | } | |
4934 | ||
4935 | rcu_read_lock(); | |
76369139 FW |
4936 | rb = rcu_dereference(event->rb); |
4937 | if (!rb) | |
906010b2 PZ |
4938 | goto unlock; |
4939 | ||
4940 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4941 | goto unlock; | |
4942 | ||
76369139 | 4943 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4944 | if (!vmf->page) |
4945 | goto unlock; | |
4946 | ||
4947 | get_page(vmf->page); | |
4948 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4949 | vmf->page->index = vmf->pgoff; | |
4950 | ||
4951 | ret = 0; | |
4952 | unlock: | |
4953 | rcu_read_unlock(); | |
4954 | ||
4955 | return ret; | |
4956 | } | |
4957 | ||
10c6db11 PZ |
4958 | static void ring_buffer_attach(struct perf_event *event, |
4959 | struct ring_buffer *rb) | |
4960 | { | |
b69cf536 | 4961 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4962 | unsigned long flags; |
4963 | ||
b69cf536 PZ |
4964 | if (event->rb) { |
4965 | /* | |
4966 | * Should be impossible, we set this when removing | |
4967 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4968 | */ | |
4969 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4970 | |
b69cf536 | 4971 | old_rb = event->rb; |
b69cf536 PZ |
4972 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4973 | list_del_rcu(&event->rb_entry); | |
4974 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4975 | |
2f993cf0 ON |
4976 | event->rcu_batches = get_state_synchronize_rcu(); |
4977 | event->rcu_pending = 1; | |
b69cf536 | 4978 | } |
10c6db11 | 4979 | |
b69cf536 | 4980 | if (rb) { |
2f993cf0 ON |
4981 | if (event->rcu_pending) { |
4982 | cond_synchronize_rcu(event->rcu_batches); | |
4983 | event->rcu_pending = 0; | |
4984 | } | |
4985 | ||
b69cf536 PZ |
4986 | spin_lock_irqsave(&rb->event_lock, flags); |
4987 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4988 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4989 | } | |
4990 | ||
767ae086 AS |
4991 | /* |
4992 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
4993 | * before swizzling the event::rb pointer; if it's getting | |
4994 | * unmapped, its aux_mmap_count will be 0 and it won't | |
4995 | * restart. See the comment in __perf_pmu_output_stop(). | |
4996 | * | |
4997 | * Data will inevitably be lost when set_output is done in | |
4998 | * mid-air, but then again, whoever does it like this is | |
4999 | * not in for the data anyway. | |
5000 | */ | |
5001 | if (has_aux(event)) | |
5002 | perf_event_stop(event, 0); | |
5003 | ||
b69cf536 PZ |
5004 | rcu_assign_pointer(event->rb, rb); |
5005 | ||
5006 | if (old_rb) { | |
5007 | ring_buffer_put(old_rb); | |
5008 | /* | |
5009 | * Since we detached before setting the new rb, so that we | |
5010 | * could attach the new rb, we could have missed a wakeup. | |
5011 | * Provide it now. | |
5012 | */ | |
5013 | wake_up_all(&event->waitq); | |
5014 | } | |
10c6db11 PZ |
5015 | } |
5016 | ||
5017 | static void ring_buffer_wakeup(struct perf_event *event) | |
5018 | { | |
5019 | struct ring_buffer *rb; | |
5020 | ||
5021 | rcu_read_lock(); | |
5022 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5023 | if (rb) { |
5024 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5025 | wake_up_all(&event->waitq); | |
5026 | } | |
10c6db11 PZ |
5027 | rcu_read_unlock(); |
5028 | } | |
5029 | ||
fdc26706 | 5030 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5031 | { |
76369139 | 5032 | struct ring_buffer *rb; |
7b732a75 | 5033 | |
ac9721f3 | 5034 | rcu_read_lock(); |
76369139 FW |
5035 | rb = rcu_dereference(event->rb); |
5036 | if (rb) { | |
5037 | if (!atomic_inc_not_zero(&rb->refcount)) | |
5038 | rb = NULL; | |
ac9721f3 PZ |
5039 | } |
5040 | rcu_read_unlock(); | |
5041 | ||
76369139 | 5042 | return rb; |
ac9721f3 PZ |
5043 | } |
5044 | ||
fdc26706 | 5045 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5046 | { |
76369139 | 5047 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 5048 | return; |
7b732a75 | 5049 | |
9bb5d40c | 5050 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5051 | |
76369139 | 5052 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5053 | } |
5054 | ||
5055 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5056 | { | |
cdd6c482 | 5057 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5058 | |
cdd6c482 | 5059 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5060 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5061 | |
45bfb2e5 PZ |
5062 | if (vma->vm_pgoff) |
5063 | atomic_inc(&event->rb->aux_mmap_count); | |
5064 | ||
1e0fb9ec AL |
5065 | if (event->pmu->event_mapped) |
5066 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
5067 | } |
5068 | ||
95ff4ca2 AS |
5069 | static void perf_pmu_output_stop(struct perf_event *event); |
5070 | ||
9bb5d40c PZ |
5071 | /* |
5072 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5073 | * event, or through other events by use of perf_event_set_output(). | |
5074 | * | |
5075 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5076 | * the buffer here, where we still have a VM context. This means we need | |
5077 | * to detach all events redirecting to us. | |
5078 | */ | |
7b732a75 PZ |
5079 | static void perf_mmap_close(struct vm_area_struct *vma) |
5080 | { | |
cdd6c482 | 5081 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5082 | |
b69cf536 | 5083 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5084 | struct user_struct *mmap_user = rb->mmap_user; |
5085 | int mmap_locked = rb->mmap_locked; | |
5086 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5087 | |
1e0fb9ec AL |
5088 | if (event->pmu->event_unmapped) |
5089 | event->pmu->event_unmapped(event); | |
5090 | ||
45bfb2e5 PZ |
5091 | /* |
5092 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5093 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5094 | * serialize with perf_mmap here. | |
5095 | */ | |
5096 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5097 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5098 | /* |
5099 | * Stop all AUX events that are writing to this buffer, | |
5100 | * so that we can free its AUX pages and corresponding PMU | |
5101 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5102 | * they won't start any more (see perf_aux_output_begin()). | |
5103 | */ | |
5104 | perf_pmu_output_stop(event); | |
5105 | ||
5106 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5107 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5108 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5109 | ||
95ff4ca2 | 5110 | /* this has to be the last one */ |
45bfb2e5 | 5111 | rb_free_aux(rb); |
95ff4ca2 AS |
5112 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5113 | ||
45bfb2e5 PZ |
5114 | mutex_unlock(&event->mmap_mutex); |
5115 | } | |
5116 | ||
9bb5d40c PZ |
5117 | atomic_dec(&rb->mmap_count); |
5118 | ||
5119 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5120 | goto out_put; |
9bb5d40c | 5121 | |
b69cf536 | 5122 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5123 | mutex_unlock(&event->mmap_mutex); |
5124 | ||
5125 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5126 | if (atomic_read(&rb->mmap_count)) |
5127 | goto out_put; | |
ac9721f3 | 5128 | |
9bb5d40c PZ |
5129 | /* |
5130 | * No other mmap()s, detach from all other events that might redirect | |
5131 | * into the now unreachable buffer. Somewhat complicated by the | |
5132 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5133 | */ | |
5134 | again: | |
5135 | rcu_read_lock(); | |
5136 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5137 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5138 | /* | |
5139 | * This event is en-route to free_event() which will | |
5140 | * detach it and remove it from the list. | |
5141 | */ | |
5142 | continue; | |
5143 | } | |
5144 | rcu_read_unlock(); | |
789f90fc | 5145 | |
9bb5d40c PZ |
5146 | mutex_lock(&event->mmap_mutex); |
5147 | /* | |
5148 | * Check we didn't race with perf_event_set_output() which can | |
5149 | * swizzle the rb from under us while we were waiting to | |
5150 | * acquire mmap_mutex. | |
5151 | * | |
5152 | * If we find a different rb; ignore this event, a next | |
5153 | * iteration will no longer find it on the list. We have to | |
5154 | * still restart the iteration to make sure we're not now | |
5155 | * iterating the wrong list. | |
5156 | */ | |
b69cf536 PZ |
5157 | if (event->rb == rb) |
5158 | ring_buffer_attach(event, NULL); | |
5159 | ||
cdd6c482 | 5160 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5161 | put_event(event); |
ac9721f3 | 5162 | |
9bb5d40c PZ |
5163 | /* |
5164 | * Restart the iteration; either we're on the wrong list or | |
5165 | * destroyed its integrity by doing a deletion. | |
5166 | */ | |
5167 | goto again; | |
7b732a75 | 5168 | } |
9bb5d40c PZ |
5169 | rcu_read_unlock(); |
5170 | ||
5171 | /* | |
5172 | * It could be there's still a few 0-ref events on the list; they'll | |
5173 | * get cleaned up by free_event() -- they'll also still have their | |
5174 | * ref on the rb and will free it whenever they are done with it. | |
5175 | * | |
5176 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5177 | * undo the VM accounting. | |
5178 | */ | |
5179 | ||
5180 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5181 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5182 | free_uid(mmap_user); | |
5183 | ||
b69cf536 | 5184 | out_put: |
9bb5d40c | 5185 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5186 | } |
5187 | ||
f0f37e2f | 5188 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5189 | .open = perf_mmap_open, |
45bfb2e5 | 5190 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5191 | .fault = perf_mmap_fault, |
5192 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5193 | }; |
5194 | ||
5195 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5196 | { | |
cdd6c482 | 5197 | struct perf_event *event = file->private_data; |
22a4f650 | 5198 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5199 | struct user_struct *user = current_user(); |
22a4f650 | 5200 | unsigned long locked, lock_limit; |
45bfb2e5 | 5201 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5202 | unsigned long vma_size; |
5203 | unsigned long nr_pages; | |
45bfb2e5 | 5204 | long user_extra = 0, extra = 0; |
d57e34fd | 5205 | int ret = 0, flags = 0; |
37d81828 | 5206 | |
c7920614 PZ |
5207 | /* |
5208 | * Don't allow mmap() of inherited per-task counters. This would | |
5209 | * create a performance issue due to all children writing to the | |
76369139 | 5210 | * same rb. |
c7920614 PZ |
5211 | */ |
5212 | if (event->cpu == -1 && event->attr.inherit) | |
5213 | return -EINVAL; | |
5214 | ||
43a21ea8 | 5215 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5216 | return -EINVAL; |
7b732a75 PZ |
5217 | |
5218 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5219 | |
5220 | if (vma->vm_pgoff == 0) { | |
5221 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5222 | } else { | |
5223 | /* | |
5224 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5225 | * mapped, all subsequent mappings should have the same size | |
5226 | * and offset. Must be above the normal perf buffer. | |
5227 | */ | |
5228 | u64 aux_offset, aux_size; | |
5229 | ||
5230 | if (!event->rb) | |
5231 | return -EINVAL; | |
5232 | ||
5233 | nr_pages = vma_size / PAGE_SIZE; | |
5234 | ||
5235 | mutex_lock(&event->mmap_mutex); | |
5236 | ret = -EINVAL; | |
5237 | ||
5238 | rb = event->rb; | |
5239 | if (!rb) | |
5240 | goto aux_unlock; | |
5241 | ||
5242 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5243 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5244 | ||
5245 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5246 | goto aux_unlock; | |
5247 | ||
5248 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5249 | goto aux_unlock; | |
5250 | ||
5251 | /* already mapped with a different offset */ | |
5252 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5253 | goto aux_unlock; | |
5254 | ||
5255 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5256 | goto aux_unlock; | |
5257 | ||
5258 | /* already mapped with a different size */ | |
5259 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5260 | goto aux_unlock; | |
5261 | ||
5262 | if (!is_power_of_2(nr_pages)) | |
5263 | goto aux_unlock; | |
5264 | ||
5265 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5266 | goto aux_unlock; | |
5267 | ||
5268 | if (rb_has_aux(rb)) { | |
5269 | atomic_inc(&rb->aux_mmap_count); | |
5270 | ret = 0; | |
5271 | goto unlock; | |
5272 | } | |
5273 | ||
5274 | atomic_set(&rb->aux_mmap_count, 1); | |
5275 | user_extra = nr_pages; | |
5276 | ||
5277 | goto accounting; | |
5278 | } | |
7b732a75 | 5279 | |
7730d865 | 5280 | /* |
76369139 | 5281 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5282 | * can do bitmasks instead of modulo. |
5283 | */ | |
2ed11312 | 5284 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5285 | return -EINVAL; |
5286 | ||
7b732a75 | 5287 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5288 | return -EINVAL; |
5289 | ||
cdd6c482 | 5290 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5291 | again: |
cdd6c482 | 5292 | mutex_lock(&event->mmap_mutex); |
76369139 | 5293 | if (event->rb) { |
9bb5d40c | 5294 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5295 | ret = -EINVAL; |
9bb5d40c PZ |
5296 | goto unlock; |
5297 | } | |
5298 | ||
5299 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5300 | /* | |
5301 | * Raced against perf_mmap_close() through | |
5302 | * perf_event_set_output(). Try again, hope for better | |
5303 | * luck. | |
5304 | */ | |
5305 | mutex_unlock(&event->mmap_mutex); | |
5306 | goto again; | |
5307 | } | |
5308 | ||
ebb3c4c4 PZ |
5309 | goto unlock; |
5310 | } | |
5311 | ||
789f90fc | 5312 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5313 | |
5314 | accounting: | |
cdd6c482 | 5315 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5316 | |
5317 | /* | |
5318 | * Increase the limit linearly with more CPUs: | |
5319 | */ | |
5320 | user_lock_limit *= num_online_cpus(); | |
5321 | ||
789f90fc | 5322 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5323 | |
789f90fc PZ |
5324 | if (user_locked > user_lock_limit) |
5325 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5326 | |
78d7d407 | 5327 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5328 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5329 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5330 | |
459ec28a IM |
5331 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5332 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5333 | ret = -EPERM; |
5334 | goto unlock; | |
5335 | } | |
7b732a75 | 5336 | |
45bfb2e5 | 5337 | WARN_ON(!rb && event->rb); |
906010b2 | 5338 | |
d57e34fd | 5339 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5340 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5341 | |
76369139 | 5342 | if (!rb) { |
45bfb2e5 PZ |
5343 | rb = rb_alloc(nr_pages, |
5344 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5345 | event->cpu, flags); | |
26cb63ad | 5346 | |
45bfb2e5 PZ |
5347 | if (!rb) { |
5348 | ret = -ENOMEM; | |
5349 | goto unlock; | |
5350 | } | |
43a21ea8 | 5351 | |
45bfb2e5 PZ |
5352 | atomic_set(&rb->mmap_count, 1); |
5353 | rb->mmap_user = get_current_user(); | |
5354 | rb->mmap_locked = extra; | |
26cb63ad | 5355 | |
45bfb2e5 | 5356 | ring_buffer_attach(event, rb); |
ac9721f3 | 5357 | |
45bfb2e5 PZ |
5358 | perf_event_init_userpage(event); |
5359 | perf_event_update_userpage(event); | |
5360 | } else { | |
1a594131 AS |
5361 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5362 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5363 | if (!ret) |
5364 | rb->aux_mmap_locked = extra; | |
5365 | } | |
9a0f05cb | 5366 | |
ebb3c4c4 | 5367 | unlock: |
45bfb2e5 PZ |
5368 | if (!ret) { |
5369 | atomic_long_add(user_extra, &user->locked_vm); | |
5370 | vma->vm_mm->pinned_vm += extra; | |
5371 | ||
ac9721f3 | 5372 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5373 | } else if (rb) { |
5374 | atomic_dec(&rb->mmap_count); | |
5375 | } | |
5376 | aux_unlock: | |
cdd6c482 | 5377 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5378 | |
9bb5d40c PZ |
5379 | /* |
5380 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5381 | * vma. | |
5382 | */ | |
26cb63ad | 5383 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5384 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5385 | |
1e0fb9ec AL |
5386 | if (event->pmu->event_mapped) |
5387 | event->pmu->event_mapped(event); | |
5388 | ||
7b732a75 | 5389 | return ret; |
37d81828 PM |
5390 | } |
5391 | ||
3c446b3d PZ |
5392 | static int perf_fasync(int fd, struct file *filp, int on) |
5393 | { | |
496ad9aa | 5394 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5395 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5396 | int retval; |
5397 | ||
5955102c | 5398 | inode_lock(inode); |
cdd6c482 | 5399 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5400 | inode_unlock(inode); |
3c446b3d PZ |
5401 | |
5402 | if (retval < 0) | |
5403 | return retval; | |
5404 | ||
5405 | return 0; | |
5406 | } | |
5407 | ||
0793a61d | 5408 | static const struct file_operations perf_fops = { |
3326c1ce | 5409 | .llseek = no_llseek, |
0793a61d TG |
5410 | .release = perf_release, |
5411 | .read = perf_read, | |
5412 | .poll = perf_poll, | |
d859e29f | 5413 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5414 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5415 | .mmap = perf_mmap, |
3c446b3d | 5416 | .fasync = perf_fasync, |
0793a61d TG |
5417 | }; |
5418 | ||
925d519a | 5419 | /* |
cdd6c482 | 5420 | * Perf event wakeup |
925d519a PZ |
5421 | * |
5422 | * If there's data, ensure we set the poll() state and publish everything | |
5423 | * to user-space before waking everybody up. | |
5424 | */ | |
5425 | ||
fed66e2c PZ |
5426 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5427 | { | |
5428 | /* only the parent has fasync state */ | |
5429 | if (event->parent) | |
5430 | event = event->parent; | |
5431 | return &event->fasync; | |
5432 | } | |
5433 | ||
cdd6c482 | 5434 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5435 | { |
10c6db11 | 5436 | ring_buffer_wakeup(event); |
4c9e2542 | 5437 | |
cdd6c482 | 5438 | if (event->pending_kill) { |
fed66e2c | 5439 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5440 | event->pending_kill = 0; |
4c9e2542 | 5441 | } |
925d519a PZ |
5442 | } |
5443 | ||
e360adbe | 5444 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5445 | { |
cdd6c482 IM |
5446 | struct perf_event *event = container_of(entry, |
5447 | struct perf_event, pending); | |
d525211f PZ |
5448 | int rctx; |
5449 | ||
5450 | rctx = perf_swevent_get_recursion_context(); | |
5451 | /* | |
5452 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5453 | * and we won't recurse 'further'. | |
5454 | */ | |
79f14641 | 5455 | |
cdd6c482 IM |
5456 | if (event->pending_disable) { |
5457 | event->pending_disable = 0; | |
fae3fde6 | 5458 | perf_event_disable_local(event); |
79f14641 PZ |
5459 | } |
5460 | ||
cdd6c482 IM |
5461 | if (event->pending_wakeup) { |
5462 | event->pending_wakeup = 0; | |
5463 | perf_event_wakeup(event); | |
79f14641 | 5464 | } |
d525211f PZ |
5465 | |
5466 | if (rctx >= 0) | |
5467 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5468 | } |
5469 | ||
39447b38 ZY |
5470 | /* |
5471 | * We assume there is only KVM supporting the callbacks. | |
5472 | * Later on, we might change it to a list if there is | |
5473 | * another virtualization implementation supporting the callbacks. | |
5474 | */ | |
5475 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5476 | ||
5477 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5478 | { | |
5479 | perf_guest_cbs = cbs; | |
5480 | return 0; | |
5481 | } | |
5482 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5483 | ||
5484 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5485 | { | |
5486 | perf_guest_cbs = NULL; | |
5487 | return 0; | |
5488 | } | |
5489 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5490 | ||
4018994f JO |
5491 | static void |
5492 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5493 | struct pt_regs *regs, u64 mask) | |
5494 | { | |
5495 | int bit; | |
29dd3288 | 5496 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5497 | |
29dd3288 MS |
5498 | bitmap_from_u64(_mask, mask); |
5499 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5500 | u64 val; |
5501 | ||
5502 | val = perf_reg_value(regs, bit); | |
5503 | perf_output_put(handle, val); | |
5504 | } | |
5505 | } | |
5506 | ||
60e2364e | 5507 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5508 | struct pt_regs *regs, |
5509 | struct pt_regs *regs_user_copy) | |
4018994f | 5510 | { |
88a7c26a AL |
5511 | if (user_mode(regs)) { |
5512 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5513 | regs_user->regs = regs; |
88a7c26a AL |
5514 | } else if (current->mm) { |
5515 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5516 | } else { |
5517 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5518 | regs_user->regs = NULL; | |
4018994f JO |
5519 | } |
5520 | } | |
5521 | ||
60e2364e SE |
5522 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5523 | struct pt_regs *regs) | |
5524 | { | |
5525 | regs_intr->regs = regs; | |
5526 | regs_intr->abi = perf_reg_abi(current); | |
5527 | } | |
5528 | ||
5529 | ||
c5ebcedb JO |
5530 | /* |
5531 | * Get remaining task size from user stack pointer. | |
5532 | * | |
5533 | * It'd be better to take stack vma map and limit this more | |
5534 | * precisly, but there's no way to get it safely under interrupt, | |
5535 | * so using TASK_SIZE as limit. | |
5536 | */ | |
5537 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5538 | { | |
5539 | unsigned long addr = perf_user_stack_pointer(regs); | |
5540 | ||
5541 | if (!addr || addr >= TASK_SIZE) | |
5542 | return 0; | |
5543 | ||
5544 | return TASK_SIZE - addr; | |
5545 | } | |
5546 | ||
5547 | static u16 | |
5548 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5549 | struct pt_regs *regs) | |
5550 | { | |
5551 | u64 task_size; | |
5552 | ||
5553 | /* No regs, no stack pointer, no dump. */ | |
5554 | if (!regs) | |
5555 | return 0; | |
5556 | ||
5557 | /* | |
5558 | * Check if we fit in with the requested stack size into the: | |
5559 | * - TASK_SIZE | |
5560 | * If we don't, we limit the size to the TASK_SIZE. | |
5561 | * | |
5562 | * - remaining sample size | |
5563 | * If we don't, we customize the stack size to | |
5564 | * fit in to the remaining sample size. | |
5565 | */ | |
5566 | ||
5567 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5568 | stack_size = min(stack_size, (u16) task_size); | |
5569 | ||
5570 | /* Current header size plus static size and dynamic size. */ | |
5571 | header_size += 2 * sizeof(u64); | |
5572 | ||
5573 | /* Do we fit in with the current stack dump size? */ | |
5574 | if ((u16) (header_size + stack_size) < header_size) { | |
5575 | /* | |
5576 | * If we overflow the maximum size for the sample, | |
5577 | * we customize the stack dump size to fit in. | |
5578 | */ | |
5579 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5580 | stack_size = round_up(stack_size, sizeof(u64)); | |
5581 | } | |
5582 | ||
5583 | return stack_size; | |
5584 | } | |
5585 | ||
5586 | static void | |
5587 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5588 | struct pt_regs *regs) | |
5589 | { | |
5590 | /* Case of a kernel thread, nothing to dump */ | |
5591 | if (!regs) { | |
5592 | u64 size = 0; | |
5593 | perf_output_put(handle, size); | |
5594 | } else { | |
5595 | unsigned long sp; | |
5596 | unsigned int rem; | |
5597 | u64 dyn_size; | |
5598 | ||
5599 | /* | |
5600 | * We dump: | |
5601 | * static size | |
5602 | * - the size requested by user or the best one we can fit | |
5603 | * in to the sample max size | |
5604 | * data | |
5605 | * - user stack dump data | |
5606 | * dynamic size | |
5607 | * - the actual dumped size | |
5608 | */ | |
5609 | ||
5610 | /* Static size. */ | |
5611 | perf_output_put(handle, dump_size); | |
5612 | ||
5613 | /* Data. */ | |
5614 | sp = perf_user_stack_pointer(regs); | |
5615 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5616 | dyn_size = dump_size - rem; | |
5617 | ||
5618 | perf_output_skip(handle, rem); | |
5619 | ||
5620 | /* Dynamic size. */ | |
5621 | perf_output_put(handle, dyn_size); | |
5622 | } | |
5623 | } | |
5624 | ||
c980d109 ACM |
5625 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5626 | struct perf_sample_data *data, | |
5627 | struct perf_event *event) | |
6844c09d ACM |
5628 | { |
5629 | u64 sample_type = event->attr.sample_type; | |
5630 | ||
5631 | data->type = sample_type; | |
5632 | header->size += event->id_header_size; | |
5633 | ||
5634 | if (sample_type & PERF_SAMPLE_TID) { | |
5635 | /* namespace issues */ | |
5636 | data->tid_entry.pid = perf_event_pid(event, current); | |
5637 | data->tid_entry.tid = perf_event_tid(event, current); | |
5638 | } | |
5639 | ||
5640 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5641 | data->time = perf_event_clock(event); |
6844c09d | 5642 | |
ff3d527c | 5643 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5644 | data->id = primary_event_id(event); |
5645 | ||
5646 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5647 | data->stream_id = event->id; | |
5648 | ||
5649 | if (sample_type & PERF_SAMPLE_CPU) { | |
5650 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5651 | data->cpu_entry.reserved = 0; | |
5652 | } | |
5653 | } | |
5654 | ||
76369139 FW |
5655 | void perf_event_header__init_id(struct perf_event_header *header, |
5656 | struct perf_sample_data *data, | |
5657 | struct perf_event *event) | |
c980d109 ACM |
5658 | { |
5659 | if (event->attr.sample_id_all) | |
5660 | __perf_event_header__init_id(header, data, event); | |
5661 | } | |
5662 | ||
5663 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5664 | struct perf_sample_data *data) | |
5665 | { | |
5666 | u64 sample_type = data->type; | |
5667 | ||
5668 | if (sample_type & PERF_SAMPLE_TID) | |
5669 | perf_output_put(handle, data->tid_entry); | |
5670 | ||
5671 | if (sample_type & PERF_SAMPLE_TIME) | |
5672 | perf_output_put(handle, data->time); | |
5673 | ||
5674 | if (sample_type & PERF_SAMPLE_ID) | |
5675 | perf_output_put(handle, data->id); | |
5676 | ||
5677 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5678 | perf_output_put(handle, data->stream_id); | |
5679 | ||
5680 | if (sample_type & PERF_SAMPLE_CPU) | |
5681 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5682 | |
5683 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5684 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5685 | } |
5686 | ||
76369139 FW |
5687 | void perf_event__output_id_sample(struct perf_event *event, |
5688 | struct perf_output_handle *handle, | |
5689 | struct perf_sample_data *sample) | |
c980d109 ACM |
5690 | { |
5691 | if (event->attr.sample_id_all) | |
5692 | __perf_event__output_id_sample(handle, sample); | |
5693 | } | |
5694 | ||
3dab77fb | 5695 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5696 | struct perf_event *event, |
5697 | u64 enabled, u64 running) | |
3dab77fb | 5698 | { |
cdd6c482 | 5699 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5700 | u64 values[4]; |
5701 | int n = 0; | |
5702 | ||
b5e58793 | 5703 | values[n++] = perf_event_count(event); |
3dab77fb | 5704 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5705 | values[n++] = enabled + |
cdd6c482 | 5706 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5707 | } |
5708 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5709 | values[n++] = running + |
cdd6c482 | 5710 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5711 | } |
5712 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5713 | values[n++] = primary_event_id(event); |
3dab77fb | 5714 | |
76369139 | 5715 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5716 | } |
5717 | ||
5718 | /* | |
cdd6c482 | 5719 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5720 | */ |
5721 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5722 | struct perf_event *event, |
5723 | u64 enabled, u64 running) | |
3dab77fb | 5724 | { |
cdd6c482 IM |
5725 | struct perf_event *leader = event->group_leader, *sub; |
5726 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5727 | u64 values[5]; |
5728 | int n = 0; | |
5729 | ||
5730 | values[n++] = 1 + leader->nr_siblings; | |
5731 | ||
5732 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5733 | values[n++] = enabled; |
3dab77fb PZ |
5734 | |
5735 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5736 | values[n++] = running; |
3dab77fb | 5737 | |
cdd6c482 | 5738 | if (leader != event) |
3dab77fb PZ |
5739 | leader->pmu->read(leader); |
5740 | ||
b5e58793 | 5741 | values[n++] = perf_event_count(leader); |
3dab77fb | 5742 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5743 | values[n++] = primary_event_id(leader); |
3dab77fb | 5744 | |
76369139 | 5745 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5746 | |
65abc865 | 5747 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5748 | n = 0; |
5749 | ||
6f5ab001 JO |
5750 | if ((sub != event) && |
5751 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5752 | sub->pmu->read(sub); |
5753 | ||
b5e58793 | 5754 | values[n++] = perf_event_count(sub); |
3dab77fb | 5755 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5756 | values[n++] = primary_event_id(sub); |
3dab77fb | 5757 | |
76369139 | 5758 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5759 | } |
5760 | } | |
5761 | ||
eed01528 SE |
5762 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5763 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5764 | ||
3dab77fb | 5765 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5766 | struct perf_event *event) |
3dab77fb | 5767 | { |
e3f3541c | 5768 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5769 | u64 read_format = event->attr.read_format; |
5770 | ||
5771 | /* | |
5772 | * compute total_time_enabled, total_time_running | |
5773 | * based on snapshot values taken when the event | |
5774 | * was last scheduled in. | |
5775 | * | |
5776 | * we cannot simply called update_context_time() | |
5777 | * because of locking issue as we are called in | |
5778 | * NMI context | |
5779 | */ | |
c4794295 | 5780 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5781 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5782 | |
cdd6c482 | 5783 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5784 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5785 | else |
eed01528 | 5786 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5787 | } |
5788 | ||
5622f295 MM |
5789 | void perf_output_sample(struct perf_output_handle *handle, |
5790 | struct perf_event_header *header, | |
5791 | struct perf_sample_data *data, | |
cdd6c482 | 5792 | struct perf_event *event) |
5622f295 MM |
5793 | { |
5794 | u64 sample_type = data->type; | |
5795 | ||
5796 | perf_output_put(handle, *header); | |
5797 | ||
ff3d527c AH |
5798 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5799 | perf_output_put(handle, data->id); | |
5800 | ||
5622f295 MM |
5801 | if (sample_type & PERF_SAMPLE_IP) |
5802 | perf_output_put(handle, data->ip); | |
5803 | ||
5804 | if (sample_type & PERF_SAMPLE_TID) | |
5805 | perf_output_put(handle, data->tid_entry); | |
5806 | ||
5807 | if (sample_type & PERF_SAMPLE_TIME) | |
5808 | perf_output_put(handle, data->time); | |
5809 | ||
5810 | if (sample_type & PERF_SAMPLE_ADDR) | |
5811 | perf_output_put(handle, data->addr); | |
5812 | ||
5813 | if (sample_type & PERF_SAMPLE_ID) | |
5814 | perf_output_put(handle, data->id); | |
5815 | ||
5816 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5817 | perf_output_put(handle, data->stream_id); | |
5818 | ||
5819 | if (sample_type & PERF_SAMPLE_CPU) | |
5820 | perf_output_put(handle, data->cpu_entry); | |
5821 | ||
5822 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5823 | perf_output_put(handle, data->period); | |
5824 | ||
5825 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5826 | perf_output_read(handle, event); |
5622f295 MM |
5827 | |
5828 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5829 | if (data->callchain) { | |
5830 | int size = 1; | |
5831 | ||
5832 | if (data->callchain) | |
5833 | size += data->callchain->nr; | |
5834 | ||
5835 | size *= sizeof(u64); | |
5836 | ||
76369139 | 5837 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5838 | } else { |
5839 | u64 nr = 0; | |
5840 | perf_output_put(handle, nr); | |
5841 | } | |
5842 | } | |
5843 | ||
5844 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5845 | struct perf_raw_record *raw = data->raw; |
5846 | ||
5847 | if (raw) { | |
5848 | struct perf_raw_frag *frag = &raw->frag; | |
5849 | ||
5850 | perf_output_put(handle, raw->size); | |
5851 | do { | |
5852 | if (frag->copy) { | |
5853 | __output_custom(handle, frag->copy, | |
5854 | frag->data, frag->size); | |
5855 | } else { | |
5856 | __output_copy(handle, frag->data, | |
5857 | frag->size); | |
5858 | } | |
5859 | if (perf_raw_frag_last(frag)) | |
5860 | break; | |
5861 | frag = frag->next; | |
5862 | } while (1); | |
5863 | if (frag->pad) | |
5864 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5865 | } else { |
5866 | struct { | |
5867 | u32 size; | |
5868 | u32 data; | |
5869 | } raw = { | |
5870 | .size = sizeof(u32), | |
5871 | .data = 0, | |
5872 | }; | |
5873 | perf_output_put(handle, raw); | |
5874 | } | |
5875 | } | |
a7ac67ea | 5876 | |
bce38cd5 SE |
5877 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5878 | if (data->br_stack) { | |
5879 | size_t size; | |
5880 | ||
5881 | size = data->br_stack->nr | |
5882 | * sizeof(struct perf_branch_entry); | |
5883 | ||
5884 | perf_output_put(handle, data->br_stack->nr); | |
5885 | perf_output_copy(handle, data->br_stack->entries, size); | |
5886 | } else { | |
5887 | /* | |
5888 | * we always store at least the value of nr | |
5889 | */ | |
5890 | u64 nr = 0; | |
5891 | perf_output_put(handle, nr); | |
5892 | } | |
5893 | } | |
4018994f JO |
5894 | |
5895 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5896 | u64 abi = data->regs_user.abi; | |
5897 | ||
5898 | /* | |
5899 | * If there are no regs to dump, notice it through | |
5900 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5901 | */ | |
5902 | perf_output_put(handle, abi); | |
5903 | ||
5904 | if (abi) { | |
5905 | u64 mask = event->attr.sample_regs_user; | |
5906 | perf_output_sample_regs(handle, | |
5907 | data->regs_user.regs, | |
5908 | mask); | |
5909 | } | |
5910 | } | |
c5ebcedb | 5911 | |
a5cdd40c | 5912 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5913 | perf_output_sample_ustack(handle, |
5914 | data->stack_user_size, | |
5915 | data->regs_user.regs); | |
a5cdd40c | 5916 | } |
c3feedf2 AK |
5917 | |
5918 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5919 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5920 | |
5921 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5922 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5923 | |
fdfbbd07 AK |
5924 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5925 | perf_output_put(handle, data->txn); | |
5926 | ||
60e2364e SE |
5927 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5928 | u64 abi = data->regs_intr.abi; | |
5929 | /* | |
5930 | * If there are no regs to dump, notice it through | |
5931 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5932 | */ | |
5933 | perf_output_put(handle, abi); | |
5934 | ||
5935 | if (abi) { | |
5936 | u64 mask = event->attr.sample_regs_intr; | |
5937 | ||
5938 | perf_output_sample_regs(handle, | |
5939 | data->regs_intr.regs, | |
5940 | mask); | |
5941 | } | |
5942 | } | |
5943 | ||
a5cdd40c PZ |
5944 | if (!event->attr.watermark) { |
5945 | int wakeup_events = event->attr.wakeup_events; | |
5946 | ||
5947 | if (wakeup_events) { | |
5948 | struct ring_buffer *rb = handle->rb; | |
5949 | int events = local_inc_return(&rb->events); | |
5950 | ||
5951 | if (events >= wakeup_events) { | |
5952 | local_sub(wakeup_events, &rb->events); | |
5953 | local_inc(&rb->wakeup); | |
5954 | } | |
5955 | } | |
5956 | } | |
5622f295 MM |
5957 | } |
5958 | ||
5959 | void perf_prepare_sample(struct perf_event_header *header, | |
5960 | struct perf_sample_data *data, | |
cdd6c482 | 5961 | struct perf_event *event, |
5622f295 | 5962 | struct pt_regs *regs) |
7b732a75 | 5963 | { |
cdd6c482 | 5964 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5965 | |
cdd6c482 | 5966 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5967 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5968 | |
5969 | header->misc = 0; | |
5970 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5971 | |
c980d109 | 5972 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5973 | |
c320c7b7 | 5974 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5975 | data->ip = perf_instruction_pointer(regs); |
5976 | ||
b23f3325 | 5977 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5978 | int size = 1; |
394ee076 | 5979 | |
e6dab5ff | 5980 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5981 | |
5982 | if (data->callchain) | |
5983 | size += data->callchain->nr; | |
5984 | ||
5985 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5986 | } |
5987 | ||
3a43ce68 | 5988 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
5989 | struct perf_raw_record *raw = data->raw; |
5990 | int size; | |
5991 | ||
5992 | if (raw) { | |
5993 | struct perf_raw_frag *frag = &raw->frag; | |
5994 | u32 sum = 0; | |
5995 | ||
5996 | do { | |
5997 | sum += frag->size; | |
5998 | if (perf_raw_frag_last(frag)) | |
5999 | break; | |
6000 | frag = frag->next; | |
6001 | } while (1); | |
6002 | ||
6003 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6004 | raw->size = size - sizeof(u32); | |
6005 | frag->pad = raw->size - sum; | |
6006 | } else { | |
6007 | size = sizeof(u64); | |
6008 | } | |
a044560c | 6009 | |
7e3f977e | 6010 | header->size += size; |
7f453c24 | 6011 | } |
bce38cd5 SE |
6012 | |
6013 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6014 | int size = sizeof(u64); /* nr */ | |
6015 | if (data->br_stack) { | |
6016 | size += data->br_stack->nr | |
6017 | * sizeof(struct perf_branch_entry); | |
6018 | } | |
6019 | header->size += size; | |
6020 | } | |
4018994f | 6021 | |
2565711f | 6022 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6023 | perf_sample_regs_user(&data->regs_user, regs, |
6024 | &data->regs_user_copy); | |
2565711f | 6025 | |
4018994f JO |
6026 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6027 | /* regs dump ABI info */ | |
6028 | int size = sizeof(u64); | |
6029 | ||
4018994f JO |
6030 | if (data->regs_user.regs) { |
6031 | u64 mask = event->attr.sample_regs_user; | |
6032 | size += hweight64(mask) * sizeof(u64); | |
6033 | } | |
6034 | ||
6035 | header->size += size; | |
6036 | } | |
c5ebcedb JO |
6037 | |
6038 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6039 | /* | |
6040 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6041 | * processed as the last one or have additional check added | |
6042 | * in case new sample type is added, because we could eat | |
6043 | * up the rest of the sample size. | |
6044 | */ | |
c5ebcedb JO |
6045 | u16 stack_size = event->attr.sample_stack_user; |
6046 | u16 size = sizeof(u64); | |
6047 | ||
c5ebcedb | 6048 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6049 | data->regs_user.regs); |
c5ebcedb JO |
6050 | |
6051 | /* | |
6052 | * If there is something to dump, add space for the dump | |
6053 | * itself and for the field that tells the dynamic size, | |
6054 | * which is how many have been actually dumped. | |
6055 | */ | |
6056 | if (stack_size) | |
6057 | size += sizeof(u64) + stack_size; | |
6058 | ||
6059 | data->stack_user_size = stack_size; | |
6060 | header->size += size; | |
6061 | } | |
60e2364e SE |
6062 | |
6063 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6064 | /* regs dump ABI info */ | |
6065 | int size = sizeof(u64); | |
6066 | ||
6067 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6068 | ||
6069 | if (data->regs_intr.regs) { | |
6070 | u64 mask = event->attr.sample_regs_intr; | |
6071 | ||
6072 | size += hweight64(mask) * sizeof(u64); | |
6073 | } | |
6074 | ||
6075 | header->size += size; | |
6076 | } | |
5622f295 | 6077 | } |
7f453c24 | 6078 | |
9ecda41a WN |
6079 | static void __always_inline |
6080 | __perf_event_output(struct perf_event *event, | |
6081 | struct perf_sample_data *data, | |
6082 | struct pt_regs *regs, | |
6083 | int (*output_begin)(struct perf_output_handle *, | |
6084 | struct perf_event *, | |
6085 | unsigned int)) | |
5622f295 MM |
6086 | { |
6087 | struct perf_output_handle handle; | |
6088 | struct perf_event_header header; | |
689802b2 | 6089 | |
927c7a9e FW |
6090 | /* protect the callchain buffers */ |
6091 | rcu_read_lock(); | |
6092 | ||
cdd6c482 | 6093 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6094 | |
9ecda41a | 6095 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6096 | goto exit; |
0322cd6e | 6097 | |
cdd6c482 | 6098 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6099 | |
8a057d84 | 6100 | perf_output_end(&handle); |
927c7a9e FW |
6101 | |
6102 | exit: | |
6103 | rcu_read_unlock(); | |
0322cd6e PZ |
6104 | } |
6105 | ||
9ecda41a WN |
6106 | void |
6107 | perf_event_output_forward(struct perf_event *event, | |
6108 | struct perf_sample_data *data, | |
6109 | struct pt_regs *regs) | |
6110 | { | |
6111 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6112 | } | |
6113 | ||
6114 | void | |
6115 | perf_event_output_backward(struct perf_event *event, | |
6116 | struct perf_sample_data *data, | |
6117 | struct pt_regs *regs) | |
6118 | { | |
6119 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6120 | } | |
6121 | ||
6122 | void | |
6123 | perf_event_output(struct perf_event *event, | |
6124 | struct perf_sample_data *data, | |
6125 | struct pt_regs *regs) | |
6126 | { | |
6127 | __perf_event_output(event, data, regs, perf_output_begin); | |
6128 | } | |
6129 | ||
38b200d6 | 6130 | /* |
cdd6c482 | 6131 | * read event_id |
38b200d6 PZ |
6132 | */ |
6133 | ||
6134 | struct perf_read_event { | |
6135 | struct perf_event_header header; | |
6136 | ||
6137 | u32 pid; | |
6138 | u32 tid; | |
38b200d6 PZ |
6139 | }; |
6140 | ||
6141 | static void | |
cdd6c482 | 6142 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6143 | struct task_struct *task) |
6144 | { | |
6145 | struct perf_output_handle handle; | |
c980d109 | 6146 | struct perf_sample_data sample; |
dfc65094 | 6147 | struct perf_read_event read_event = { |
38b200d6 | 6148 | .header = { |
cdd6c482 | 6149 | .type = PERF_RECORD_READ, |
38b200d6 | 6150 | .misc = 0, |
c320c7b7 | 6151 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6152 | }, |
cdd6c482 IM |
6153 | .pid = perf_event_pid(event, task), |
6154 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6155 | }; |
3dab77fb | 6156 | int ret; |
38b200d6 | 6157 | |
c980d109 | 6158 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6159 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6160 | if (ret) |
6161 | return; | |
6162 | ||
dfc65094 | 6163 | perf_output_put(&handle, read_event); |
cdd6c482 | 6164 | perf_output_read(&handle, event); |
c980d109 | 6165 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6166 | |
38b200d6 PZ |
6167 | perf_output_end(&handle); |
6168 | } | |
6169 | ||
aab5b71e | 6170 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6171 | |
6172 | static void | |
aab5b71e PZ |
6173 | perf_iterate_ctx(struct perf_event_context *ctx, |
6174 | perf_iterate_f output, | |
b73e4fef | 6175 | void *data, bool all) |
52d857a8 JO |
6176 | { |
6177 | struct perf_event *event; | |
6178 | ||
6179 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6180 | if (!all) { |
6181 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6182 | continue; | |
6183 | if (!event_filter_match(event)) | |
6184 | continue; | |
6185 | } | |
6186 | ||
67516844 | 6187 | output(event, data); |
52d857a8 JO |
6188 | } |
6189 | } | |
6190 | ||
aab5b71e | 6191 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6192 | { |
6193 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6194 | struct perf_event *event; | |
6195 | ||
6196 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6197 | /* |
6198 | * Skip events that are not fully formed yet; ensure that | |
6199 | * if we observe event->ctx, both event and ctx will be | |
6200 | * complete enough. See perf_install_in_context(). | |
6201 | */ | |
6202 | if (!smp_load_acquire(&event->ctx)) | |
6203 | continue; | |
6204 | ||
f2fb6bef KL |
6205 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6206 | continue; | |
6207 | if (!event_filter_match(event)) | |
6208 | continue; | |
6209 | output(event, data); | |
6210 | } | |
6211 | } | |
6212 | ||
aab5b71e PZ |
6213 | /* |
6214 | * Iterate all events that need to receive side-band events. | |
6215 | * | |
6216 | * For new callers; ensure that account_pmu_sb_event() includes | |
6217 | * your event, otherwise it might not get delivered. | |
6218 | */ | |
52d857a8 | 6219 | static void |
aab5b71e | 6220 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6221 | struct perf_event_context *task_ctx) |
6222 | { | |
52d857a8 | 6223 | struct perf_event_context *ctx; |
52d857a8 JO |
6224 | int ctxn; |
6225 | ||
aab5b71e PZ |
6226 | rcu_read_lock(); |
6227 | preempt_disable(); | |
6228 | ||
4e93ad60 | 6229 | /* |
aab5b71e PZ |
6230 | * If we have task_ctx != NULL we only notify the task context itself. |
6231 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6232 | * context. |
6233 | */ | |
6234 | if (task_ctx) { | |
aab5b71e PZ |
6235 | perf_iterate_ctx(task_ctx, output, data, false); |
6236 | goto done; | |
4e93ad60 JO |
6237 | } |
6238 | ||
aab5b71e | 6239 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6240 | |
6241 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6242 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6243 | if (ctx) | |
aab5b71e | 6244 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6245 | } |
aab5b71e | 6246 | done: |
f2fb6bef | 6247 | preempt_enable(); |
52d857a8 | 6248 | rcu_read_unlock(); |
95ff4ca2 AS |
6249 | } |
6250 | ||
375637bc AS |
6251 | /* |
6252 | * Clear all file-based filters at exec, they'll have to be | |
6253 | * re-instated when/if these objects are mmapped again. | |
6254 | */ | |
6255 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6256 | { | |
6257 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6258 | struct perf_addr_filter *filter; | |
6259 | unsigned int restart = 0, count = 0; | |
6260 | unsigned long flags; | |
6261 | ||
6262 | if (!has_addr_filter(event)) | |
6263 | return; | |
6264 | ||
6265 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6266 | list_for_each_entry(filter, &ifh->list, entry) { | |
6267 | if (filter->inode) { | |
6268 | event->addr_filters_offs[count] = 0; | |
6269 | restart++; | |
6270 | } | |
6271 | ||
6272 | count++; | |
6273 | } | |
6274 | ||
6275 | if (restart) | |
6276 | event->addr_filters_gen++; | |
6277 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6278 | ||
6279 | if (restart) | |
767ae086 | 6280 | perf_event_stop(event, 1); |
375637bc AS |
6281 | } |
6282 | ||
6283 | void perf_event_exec(void) | |
6284 | { | |
6285 | struct perf_event_context *ctx; | |
6286 | int ctxn; | |
6287 | ||
6288 | rcu_read_lock(); | |
6289 | for_each_task_context_nr(ctxn) { | |
6290 | ctx = current->perf_event_ctxp[ctxn]; | |
6291 | if (!ctx) | |
6292 | continue; | |
6293 | ||
6294 | perf_event_enable_on_exec(ctxn); | |
6295 | ||
aab5b71e | 6296 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6297 | true); |
6298 | } | |
6299 | rcu_read_unlock(); | |
6300 | } | |
6301 | ||
95ff4ca2 AS |
6302 | struct remote_output { |
6303 | struct ring_buffer *rb; | |
6304 | int err; | |
6305 | }; | |
6306 | ||
6307 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6308 | { | |
6309 | struct perf_event *parent = event->parent; | |
6310 | struct remote_output *ro = data; | |
6311 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6312 | struct stop_event_data sd = { |
6313 | .event = event, | |
6314 | }; | |
95ff4ca2 AS |
6315 | |
6316 | if (!has_aux(event)) | |
6317 | return; | |
6318 | ||
6319 | if (!parent) | |
6320 | parent = event; | |
6321 | ||
6322 | /* | |
6323 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6324 | * ring-buffer, but it will be the child that's actually using it. |
6325 | * | |
6326 | * We are using event::rb to determine if the event should be stopped, | |
6327 | * however this may race with ring_buffer_attach() (through set_output), | |
6328 | * which will make us skip the event that actually needs to be stopped. | |
6329 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6330 | * its rb pointer. | |
95ff4ca2 AS |
6331 | */ |
6332 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6333 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6334 | } |
6335 | ||
6336 | static int __perf_pmu_output_stop(void *info) | |
6337 | { | |
6338 | struct perf_event *event = info; | |
6339 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6340 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6341 | struct remote_output ro = { |
6342 | .rb = event->rb, | |
6343 | }; | |
6344 | ||
6345 | rcu_read_lock(); | |
aab5b71e | 6346 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6347 | if (cpuctx->task_ctx) |
aab5b71e | 6348 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6349 | &ro, false); |
95ff4ca2 AS |
6350 | rcu_read_unlock(); |
6351 | ||
6352 | return ro.err; | |
6353 | } | |
6354 | ||
6355 | static void perf_pmu_output_stop(struct perf_event *event) | |
6356 | { | |
6357 | struct perf_event *iter; | |
6358 | int err, cpu; | |
6359 | ||
6360 | restart: | |
6361 | rcu_read_lock(); | |
6362 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6363 | /* | |
6364 | * For per-CPU events, we need to make sure that neither they | |
6365 | * nor their children are running; for cpu==-1 events it's | |
6366 | * sufficient to stop the event itself if it's active, since | |
6367 | * it can't have children. | |
6368 | */ | |
6369 | cpu = iter->cpu; | |
6370 | if (cpu == -1) | |
6371 | cpu = READ_ONCE(iter->oncpu); | |
6372 | ||
6373 | if (cpu == -1) | |
6374 | continue; | |
6375 | ||
6376 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6377 | if (err == -EAGAIN) { | |
6378 | rcu_read_unlock(); | |
6379 | goto restart; | |
6380 | } | |
6381 | } | |
6382 | rcu_read_unlock(); | |
52d857a8 JO |
6383 | } |
6384 | ||
60313ebe | 6385 | /* |
9f498cc5 PZ |
6386 | * task tracking -- fork/exit |
6387 | * | |
13d7a241 | 6388 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6389 | */ |
6390 | ||
9f498cc5 | 6391 | struct perf_task_event { |
3a80b4a3 | 6392 | struct task_struct *task; |
cdd6c482 | 6393 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6394 | |
6395 | struct { | |
6396 | struct perf_event_header header; | |
6397 | ||
6398 | u32 pid; | |
6399 | u32 ppid; | |
9f498cc5 PZ |
6400 | u32 tid; |
6401 | u32 ptid; | |
393b2ad8 | 6402 | u64 time; |
cdd6c482 | 6403 | } event_id; |
60313ebe PZ |
6404 | }; |
6405 | ||
67516844 JO |
6406 | static int perf_event_task_match(struct perf_event *event) |
6407 | { | |
13d7a241 SE |
6408 | return event->attr.comm || event->attr.mmap || |
6409 | event->attr.mmap2 || event->attr.mmap_data || | |
6410 | event->attr.task; | |
67516844 JO |
6411 | } |
6412 | ||
cdd6c482 | 6413 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6414 | void *data) |
60313ebe | 6415 | { |
52d857a8 | 6416 | struct perf_task_event *task_event = data; |
60313ebe | 6417 | struct perf_output_handle handle; |
c980d109 | 6418 | struct perf_sample_data sample; |
9f498cc5 | 6419 | struct task_struct *task = task_event->task; |
c980d109 | 6420 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6421 | |
67516844 JO |
6422 | if (!perf_event_task_match(event)) |
6423 | return; | |
6424 | ||
c980d109 | 6425 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6426 | |
c980d109 | 6427 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6428 | task_event->event_id.header.size); |
ef60777c | 6429 | if (ret) |
c980d109 | 6430 | goto out; |
60313ebe | 6431 | |
cdd6c482 IM |
6432 | task_event->event_id.pid = perf_event_pid(event, task); |
6433 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6434 | |
cdd6c482 IM |
6435 | task_event->event_id.tid = perf_event_tid(event, task); |
6436 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6437 | |
34f43927 PZ |
6438 | task_event->event_id.time = perf_event_clock(event); |
6439 | ||
cdd6c482 | 6440 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6441 | |
c980d109 ACM |
6442 | perf_event__output_id_sample(event, &handle, &sample); |
6443 | ||
60313ebe | 6444 | perf_output_end(&handle); |
c980d109 ACM |
6445 | out: |
6446 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6447 | } |
6448 | ||
cdd6c482 IM |
6449 | static void perf_event_task(struct task_struct *task, |
6450 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6451 | int new) |
60313ebe | 6452 | { |
9f498cc5 | 6453 | struct perf_task_event task_event; |
60313ebe | 6454 | |
cdd6c482 IM |
6455 | if (!atomic_read(&nr_comm_events) && |
6456 | !atomic_read(&nr_mmap_events) && | |
6457 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6458 | return; |
6459 | ||
9f498cc5 | 6460 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6461 | .task = task, |
6462 | .task_ctx = task_ctx, | |
cdd6c482 | 6463 | .event_id = { |
60313ebe | 6464 | .header = { |
cdd6c482 | 6465 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6466 | .misc = 0, |
cdd6c482 | 6467 | .size = sizeof(task_event.event_id), |
60313ebe | 6468 | }, |
573402db PZ |
6469 | /* .pid */ |
6470 | /* .ppid */ | |
9f498cc5 PZ |
6471 | /* .tid */ |
6472 | /* .ptid */ | |
34f43927 | 6473 | /* .time */ |
60313ebe PZ |
6474 | }, |
6475 | }; | |
6476 | ||
aab5b71e | 6477 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6478 | &task_event, |
6479 | task_ctx); | |
9f498cc5 PZ |
6480 | } |
6481 | ||
cdd6c482 | 6482 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6483 | { |
cdd6c482 | 6484 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
6485 | } |
6486 | ||
8d1b2d93 PZ |
6487 | /* |
6488 | * comm tracking | |
6489 | */ | |
6490 | ||
6491 | struct perf_comm_event { | |
22a4f650 IM |
6492 | struct task_struct *task; |
6493 | char *comm; | |
8d1b2d93 PZ |
6494 | int comm_size; |
6495 | ||
6496 | struct { | |
6497 | struct perf_event_header header; | |
6498 | ||
6499 | u32 pid; | |
6500 | u32 tid; | |
cdd6c482 | 6501 | } event_id; |
8d1b2d93 PZ |
6502 | }; |
6503 | ||
67516844 JO |
6504 | static int perf_event_comm_match(struct perf_event *event) |
6505 | { | |
6506 | return event->attr.comm; | |
6507 | } | |
6508 | ||
cdd6c482 | 6509 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6510 | void *data) |
8d1b2d93 | 6511 | { |
52d857a8 | 6512 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6513 | struct perf_output_handle handle; |
c980d109 | 6514 | struct perf_sample_data sample; |
cdd6c482 | 6515 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6516 | int ret; |
6517 | ||
67516844 JO |
6518 | if (!perf_event_comm_match(event)) |
6519 | return; | |
6520 | ||
c980d109 ACM |
6521 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6522 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6523 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6524 | |
6525 | if (ret) | |
c980d109 | 6526 | goto out; |
8d1b2d93 | 6527 | |
cdd6c482 IM |
6528 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6529 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6530 | |
cdd6c482 | 6531 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6532 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6533 | comm_event->comm_size); |
c980d109 ACM |
6534 | |
6535 | perf_event__output_id_sample(event, &handle, &sample); | |
6536 | ||
8d1b2d93 | 6537 | perf_output_end(&handle); |
c980d109 ACM |
6538 | out: |
6539 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6540 | } |
6541 | ||
cdd6c482 | 6542 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6543 | { |
413ee3b4 | 6544 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6545 | unsigned int size; |
8d1b2d93 | 6546 | |
413ee3b4 | 6547 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6548 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6549 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6550 | |
6551 | comm_event->comm = comm; | |
6552 | comm_event->comm_size = size; | |
6553 | ||
cdd6c482 | 6554 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6555 | |
aab5b71e | 6556 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6557 | comm_event, |
6558 | NULL); | |
8d1b2d93 PZ |
6559 | } |
6560 | ||
82b89778 | 6561 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6562 | { |
9ee318a7 PZ |
6563 | struct perf_comm_event comm_event; |
6564 | ||
cdd6c482 | 6565 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6566 | return; |
a63eaf34 | 6567 | |
9ee318a7 | 6568 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6569 | .task = task, |
573402db PZ |
6570 | /* .comm */ |
6571 | /* .comm_size */ | |
cdd6c482 | 6572 | .event_id = { |
573402db | 6573 | .header = { |
cdd6c482 | 6574 | .type = PERF_RECORD_COMM, |
82b89778 | 6575 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6576 | /* .size */ |
6577 | }, | |
6578 | /* .pid */ | |
6579 | /* .tid */ | |
8d1b2d93 PZ |
6580 | }, |
6581 | }; | |
6582 | ||
cdd6c482 | 6583 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6584 | } |
6585 | ||
0a4a9391 PZ |
6586 | /* |
6587 | * mmap tracking | |
6588 | */ | |
6589 | ||
6590 | struct perf_mmap_event { | |
089dd79d PZ |
6591 | struct vm_area_struct *vma; |
6592 | ||
6593 | const char *file_name; | |
6594 | int file_size; | |
13d7a241 SE |
6595 | int maj, min; |
6596 | u64 ino; | |
6597 | u64 ino_generation; | |
f972eb63 | 6598 | u32 prot, flags; |
0a4a9391 PZ |
6599 | |
6600 | struct { | |
6601 | struct perf_event_header header; | |
6602 | ||
6603 | u32 pid; | |
6604 | u32 tid; | |
6605 | u64 start; | |
6606 | u64 len; | |
6607 | u64 pgoff; | |
cdd6c482 | 6608 | } event_id; |
0a4a9391 PZ |
6609 | }; |
6610 | ||
67516844 JO |
6611 | static int perf_event_mmap_match(struct perf_event *event, |
6612 | void *data) | |
6613 | { | |
6614 | struct perf_mmap_event *mmap_event = data; | |
6615 | struct vm_area_struct *vma = mmap_event->vma; | |
6616 | int executable = vma->vm_flags & VM_EXEC; | |
6617 | ||
6618 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6619 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6620 | } |
6621 | ||
cdd6c482 | 6622 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6623 | void *data) |
0a4a9391 | 6624 | { |
52d857a8 | 6625 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6626 | struct perf_output_handle handle; |
c980d109 | 6627 | struct perf_sample_data sample; |
cdd6c482 | 6628 | int size = mmap_event->event_id.header.size; |
c980d109 | 6629 | int ret; |
0a4a9391 | 6630 | |
67516844 JO |
6631 | if (!perf_event_mmap_match(event, data)) |
6632 | return; | |
6633 | ||
13d7a241 SE |
6634 | if (event->attr.mmap2) { |
6635 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6636 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6637 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6638 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6639 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6640 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6641 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6642 | } |
6643 | ||
c980d109 ACM |
6644 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6645 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6646 | mmap_event->event_id.header.size); |
0a4a9391 | 6647 | if (ret) |
c980d109 | 6648 | goto out; |
0a4a9391 | 6649 | |
cdd6c482 IM |
6650 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6651 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6652 | |
cdd6c482 | 6653 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6654 | |
6655 | if (event->attr.mmap2) { | |
6656 | perf_output_put(&handle, mmap_event->maj); | |
6657 | perf_output_put(&handle, mmap_event->min); | |
6658 | perf_output_put(&handle, mmap_event->ino); | |
6659 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6660 | perf_output_put(&handle, mmap_event->prot); |
6661 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6662 | } |
6663 | ||
76369139 | 6664 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6665 | mmap_event->file_size); |
c980d109 ACM |
6666 | |
6667 | perf_event__output_id_sample(event, &handle, &sample); | |
6668 | ||
78d613eb | 6669 | perf_output_end(&handle); |
c980d109 ACM |
6670 | out: |
6671 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6672 | } |
6673 | ||
cdd6c482 | 6674 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6675 | { |
089dd79d PZ |
6676 | struct vm_area_struct *vma = mmap_event->vma; |
6677 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6678 | int maj = 0, min = 0; |
6679 | u64 ino = 0, gen = 0; | |
f972eb63 | 6680 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6681 | unsigned int size; |
6682 | char tmp[16]; | |
6683 | char *buf = NULL; | |
2c42cfbf | 6684 | char *name; |
413ee3b4 | 6685 | |
0b3589be PZ |
6686 | if (vma->vm_flags & VM_READ) |
6687 | prot |= PROT_READ; | |
6688 | if (vma->vm_flags & VM_WRITE) | |
6689 | prot |= PROT_WRITE; | |
6690 | if (vma->vm_flags & VM_EXEC) | |
6691 | prot |= PROT_EXEC; | |
6692 | ||
6693 | if (vma->vm_flags & VM_MAYSHARE) | |
6694 | flags = MAP_SHARED; | |
6695 | else | |
6696 | flags = MAP_PRIVATE; | |
6697 | ||
6698 | if (vma->vm_flags & VM_DENYWRITE) | |
6699 | flags |= MAP_DENYWRITE; | |
6700 | if (vma->vm_flags & VM_MAYEXEC) | |
6701 | flags |= MAP_EXECUTABLE; | |
6702 | if (vma->vm_flags & VM_LOCKED) | |
6703 | flags |= MAP_LOCKED; | |
6704 | if (vma->vm_flags & VM_HUGETLB) | |
6705 | flags |= MAP_HUGETLB; | |
6706 | ||
0a4a9391 | 6707 | if (file) { |
13d7a241 SE |
6708 | struct inode *inode; |
6709 | dev_t dev; | |
3ea2f2b9 | 6710 | |
2c42cfbf | 6711 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6712 | if (!buf) { |
c7e548b4 ON |
6713 | name = "//enomem"; |
6714 | goto cpy_name; | |
0a4a9391 | 6715 | } |
413ee3b4 | 6716 | /* |
3ea2f2b9 | 6717 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6718 | * need to add enough zero bytes after the string to handle |
6719 | * the 64bit alignment we do later. | |
6720 | */ | |
9bf39ab2 | 6721 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6722 | if (IS_ERR(name)) { |
c7e548b4 ON |
6723 | name = "//toolong"; |
6724 | goto cpy_name; | |
0a4a9391 | 6725 | } |
13d7a241 SE |
6726 | inode = file_inode(vma->vm_file); |
6727 | dev = inode->i_sb->s_dev; | |
6728 | ino = inode->i_ino; | |
6729 | gen = inode->i_generation; | |
6730 | maj = MAJOR(dev); | |
6731 | min = MINOR(dev); | |
f972eb63 | 6732 | |
c7e548b4 | 6733 | goto got_name; |
0a4a9391 | 6734 | } else { |
fbe26abe JO |
6735 | if (vma->vm_ops && vma->vm_ops->name) { |
6736 | name = (char *) vma->vm_ops->name(vma); | |
6737 | if (name) | |
6738 | goto cpy_name; | |
6739 | } | |
6740 | ||
2c42cfbf | 6741 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6742 | if (name) |
6743 | goto cpy_name; | |
089dd79d | 6744 | |
32c5fb7e | 6745 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6746 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6747 | name = "[heap]"; |
6748 | goto cpy_name; | |
32c5fb7e ON |
6749 | } |
6750 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6751 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6752 | name = "[stack]"; |
6753 | goto cpy_name; | |
089dd79d PZ |
6754 | } |
6755 | ||
c7e548b4 ON |
6756 | name = "//anon"; |
6757 | goto cpy_name; | |
0a4a9391 PZ |
6758 | } |
6759 | ||
c7e548b4 ON |
6760 | cpy_name: |
6761 | strlcpy(tmp, name, sizeof(tmp)); | |
6762 | name = tmp; | |
0a4a9391 | 6763 | got_name: |
2c42cfbf PZ |
6764 | /* |
6765 | * Since our buffer works in 8 byte units we need to align our string | |
6766 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6767 | * zero'd out to avoid leaking random bits to userspace. | |
6768 | */ | |
6769 | size = strlen(name)+1; | |
6770 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6771 | name[size++] = '\0'; | |
0a4a9391 PZ |
6772 | |
6773 | mmap_event->file_name = name; | |
6774 | mmap_event->file_size = size; | |
13d7a241 SE |
6775 | mmap_event->maj = maj; |
6776 | mmap_event->min = min; | |
6777 | mmap_event->ino = ino; | |
6778 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6779 | mmap_event->prot = prot; |
6780 | mmap_event->flags = flags; | |
0a4a9391 | 6781 | |
2fe85427 SE |
6782 | if (!(vma->vm_flags & VM_EXEC)) |
6783 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6784 | ||
cdd6c482 | 6785 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6786 | |
aab5b71e | 6787 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6788 | mmap_event, |
6789 | NULL); | |
665c2142 | 6790 | |
0a4a9391 PZ |
6791 | kfree(buf); |
6792 | } | |
6793 | ||
375637bc AS |
6794 | /* |
6795 | * Check whether inode and address range match filter criteria. | |
6796 | */ | |
6797 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6798 | struct file *file, unsigned long offset, | |
6799 | unsigned long size) | |
6800 | { | |
45063097 | 6801 | if (filter->inode != file_inode(file)) |
375637bc AS |
6802 | return false; |
6803 | ||
6804 | if (filter->offset > offset + size) | |
6805 | return false; | |
6806 | ||
6807 | if (filter->offset + filter->size < offset) | |
6808 | return false; | |
6809 | ||
6810 | return true; | |
6811 | } | |
6812 | ||
6813 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6814 | { | |
6815 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6816 | struct vm_area_struct *vma = data; | |
6817 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6818 | struct file *file = vma->vm_file; | |
6819 | struct perf_addr_filter *filter; | |
6820 | unsigned int restart = 0, count = 0; | |
6821 | ||
6822 | if (!has_addr_filter(event)) | |
6823 | return; | |
6824 | ||
6825 | if (!file) | |
6826 | return; | |
6827 | ||
6828 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6829 | list_for_each_entry(filter, &ifh->list, entry) { | |
6830 | if (perf_addr_filter_match(filter, file, off, | |
6831 | vma->vm_end - vma->vm_start)) { | |
6832 | event->addr_filters_offs[count] = vma->vm_start; | |
6833 | restart++; | |
6834 | } | |
6835 | ||
6836 | count++; | |
6837 | } | |
6838 | ||
6839 | if (restart) | |
6840 | event->addr_filters_gen++; | |
6841 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6842 | ||
6843 | if (restart) | |
767ae086 | 6844 | perf_event_stop(event, 1); |
375637bc AS |
6845 | } |
6846 | ||
6847 | /* | |
6848 | * Adjust all task's events' filters to the new vma | |
6849 | */ | |
6850 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6851 | { | |
6852 | struct perf_event_context *ctx; | |
6853 | int ctxn; | |
6854 | ||
12b40a23 MP |
6855 | /* |
6856 | * Data tracing isn't supported yet and as such there is no need | |
6857 | * to keep track of anything that isn't related to executable code: | |
6858 | */ | |
6859 | if (!(vma->vm_flags & VM_EXEC)) | |
6860 | return; | |
6861 | ||
375637bc AS |
6862 | rcu_read_lock(); |
6863 | for_each_task_context_nr(ctxn) { | |
6864 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
6865 | if (!ctx) | |
6866 | continue; | |
6867 | ||
aab5b71e | 6868 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
6869 | } |
6870 | rcu_read_unlock(); | |
6871 | } | |
6872 | ||
3af9e859 | 6873 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6874 | { |
9ee318a7 PZ |
6875 | struct perf_mmap_event mmap_event; |
6876 | ||
cdd6c482 | 6877 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6878 | return; |
6879 | ||
6880 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6881 | .vma = vma, |
573402db PZ |
6882 | /* .file_name */ |
6883 | /* .file_size */ | |
cdd6c482 | 6884 | .event_id = { |
573402db | 6885 | .header = { |
cdd6c482 | 6886 | .type = PERF_RECORD_MMAP, |
39447b38 | 6887 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6888 | /* .size */ |
6889 | }, | |
6890 | /* .pid */ | |
6891 | /* .tid */ | |
089dd79d PZ |
6892 | .start = vma->vm_start, |
6893 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6894 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6895 | }, |
13d7a241 SE |
6896 | /* .maj (attr_mmap2 only) */ |
6897 | /* .min (attr_mmap2 only) */ | |
6898 | /* .ino (attr_mmap2 only) */ | |
6899 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6900 | /* .prot (attr_mmap2 only) */ |
6901 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6902 | }; |
6903 | ||
375637bc | 6904 | perf_addr_filters_adjust(vma); |
cdd6c482 | 6905 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6906 | } |
6907 | ||
68db7e98 AS |
6908 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6909 | unsigned long size, u64 flags) | |
6910 | { | |
6911 | struct perf_output_handle handle; | |
6912 | struct perf_sample_data sample; | |
6913 | struct perf_aux_event { | |
6914 | struct perf_event_header header; | |
6915 | u64 offset; | |
6916 | u64 size; | |
6917 | u64 flags; | |
6918 | } rec = { | |
6919 | .header = { | |
6920 | .type = PERF_RECORD_AUX, | |
6921 | .misc = 0, | |
6922 | .size = sizeof(rec), | |
6923 | }, | |
6924 | .offset = head, | |
6925 | .size = size, | |
6926 | .flags = flags, | |
6927 | }; | |
6928 | int ret; | |
6929 | ||
6930 | perf_event_header__init_id(&rec.header, &sample, event); | |
6931 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6932 | ||
6933 | if (ret) | |
6934 | return; | |
6935 | ||
6936 | perf_output_put(&handle, rec); | |
6937 | perf_event__output_id_sample(event, &handle, &sample); | |
6938 | ||
6939 | perf_output_end(&handle); | |
6940 | } | |
6941 | ||
f38b0dbb KL |
6942 | /* |
6943 | * Lost/dropped samples logging | |
6944 | */ | |
6945 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6946 | { | |
6947 | struct perf_output_handle handle; | |
6948 | struct perf_sample_data sample; | |
6949 | int ret; | |
6950 | ||
6951 | struct { | |
6952 | struct perf_event_header header; | |
6953 | u64 lost; | |
6954 | } lost_samples_event = { | |
6955 | .header = { | |
6956 | .type = PERF_RECORD_LOST_SAMPLES, | |
6957 | .misc = 0, | |
6958 | .size = sizeof(lost_samples_event), | |
6959 | }, | |
6960 | .lost = lost, | |
6961 | }; | |
6962 | ||
6963 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6964 | ||
6965 | ret = perf_output_begin(&handle, event, | |
6966 | lost_samples_event.header.size); | |
6967 | if (ret) | |
6968 | return; | |
6969 | ||
6970 | perf_output_put(&handle, lost_samples_event); | |
6971 | perf_event__output_id_sample(event, &handle, &sample); | |
6972 | perf_output_end(&handle); | |
6973 | } | |
6974 | ||
45ac1403 AH |
6975 | /* |
6976 | * context_switch tracking | |
6977 | */ | |
6978 | ||
6979 | struct perf_switch_event { | |
6980 | struct task_struct *task; | |
6981 | struct task_struct *next_prev; | |
6982 | ||
6983 | struct { | |
6984 | struct perf_event_header header; | |
6985 | u32 next_prev_pid; | |
6986 | u32 next_prev_tid; | |
6987 | } event_id; | |
6988 | }; | |
6989 | ||
6990 | static int perf_event_switch_match(struct perf_event *event) | |
6991 | { | |
6992 | return event->attr.context_switch; | |
6993 | } | |
6994 | ||
6995 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6996 | { | |
6997 | struct perf_switch_event *se = data; | |
6998 | struct perf_output_handle handle; | |
6999 | struct perf_sample_data sample; | |
7000 | int ret; | |
7001 | ||
7002 | if (!perf_event_switch_match(event)) | |
7003 | return; | |
7004 | ||
7005 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7006 | if (event->ctx->task) { | |
7007 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7008 | se->event_id.header.size = sizeof(se->event_id.header); | |
7009 | } else { | |
7010 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7011 | se->event_id.header.size = sizeof(se->event_id); | |
7012 | se->event_id.next_prev_pid = | |
7013 | perf_event_pid(event, se->next_prev); | |
7014 | se->event_id.next_prev_tid = | |
7015 | perf_event_tid(event, se->next_prev); | |
7016 | } | |
7017 | ||
7018 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7019 | ||
7020 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7021 | if (ret) | |
7022 | return; | |
7023 | ||
7024 | if (event->ctx->task) | |
7025 | perf_output_put(&handle, se->event_id.header); | |
7026 | else | |
7027 | perf_output_put(&handle, se->event_id); | |
7028 | ||
7029 | perf_event__output_id_sample(event, &handle, &sample); | |
7030 | ||
7031 | perf_output_end(&handle); | |
7032 | } | |
7033 | ||
7034 | static void perf_event_switch(struct task_struct *task, | |
7035 | struct task_struct *next_prev, bool sched_in) | |
7036 | { | |
7037 | struct perf_switch_event switch_event; | |
7038 | ||
7039 | /* N.B. caller checks nr_switch_events != 0 */ | |
7040 | ||
7041 | switch_event = (struct perf_switch_event){ | |
7042 | .task = task, | |
7043 | .next_prev = next_prev, | |
7044 | .event_id = { | |
7045 | .header = { | |
7046 | /* .type */ | |
7047 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7048 | /* .size */ | |
7049 | }, | |
7050 | /* .next_prev_pid */ | |
7051 | /* .next_prev_tid */ | |
7052 | }, | |
7053 | }; | |
7054 | ||
aab5b71e | 7055 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7056 | &switch_event, |
7057 | NULL); | |
7058 | } | |
7059 | ||
a78ac325 PZ |
7060 | /* |
7061 | * IRQ throttle logging | |
7062 | */ | |
7063 | ||
cdd6c482 | 7064 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7065 | { |
7066 | struct perf_output_handle handle; | |
c980d109 | 7067 | struct perf_sample_data sample; |
a78ac325 PZ |
7068 | int ret; |
7069 | ||
7070 | struct { | |
7071 | struct perf_event_header header; | |
7072 | u64 time; | |
cca3f454 | 7073 | u64 id; |
7f453c24 | 7074 | u64 stream_id; |
a78ac325 PZ |
7075 | } throttle_event = { |
7076 | .header = { | |
cdd6c482 | 7077 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7078 | .misc = 0, |
7079 | .size = sizeof(throttle_event), | |
7080 | }, | |
34f43927 | 7081 | .time = perf_event_clock(event), |
cdd6c482 IM |
7082 | .id = primary_event_id(event), |
7083 | .stream_id = event->id, | |
a78ac325 PZ |
7084 | }; |
7085 | ||
966ee4d6 | 7086 | if (enable) |
cdd6c482 | 7087 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7088 | |
c980d109 ACM |
7089 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7090 | ||
7091 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7092 | throttle_event.header.size); |
a78ac325 PZ |
7093 | if (ret) |
7094 | return; | |
7095 | ||
7096 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7097 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7098 | perf_output_end(&handle); |
7099 | } | |
7100 | ||
ec0d7729 AS |
7101 | static void perf_log_itrace_start(struct perf_event *event) |
7102 | { | |
7103 | struct perf_output_handle handle; | |
7104 | struct perf_sample_data sample; | |
7105 | struct perf_aux_event { | |
7106 | struct perf_event_header header; | |
7107 | u32 pid; | |
7108 | u32 tid; | |
7109 | } rec; | |
7110 | int ret; | |
7111 | ||
7112 | if (event->parent) | |
7113 | event = event->parent; | |
7114 | ||
7115 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
7116 | event->hw.itrace_started) | |
7117 | return; | |
7118 | ||
ec0d7729 AS |
7119 | rec.header.type = PERF_RECORD_ITRACE_START; |
7120 | rec.header.misc = 0; | |
7121 | rec.header.size = sizeof(rec); | |
7122 | rec.pid = perf_event_pid(event, current); | |
7123 | rec.tid = perf_event_tid(event, current); | |
7124 | ||
7125 | perf_event_header__init_id(&rec.header, &sample, event); | |
7126 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7127 | ||
7128 | if (ret) | |
7129 | return; | |
7130 | ||
7131 | perf_output_put(&handle, rec); | |
7132 | perf_event__output_id_sample(event, &handle, &sample); | |
7133 | ||
7134 | perf_output_end(&handle); | |
7135 | } | |
7136 | ||
475113d9 JO |
7137 | static int |
7138 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7139 | { |
cdd6c482 | 7140 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7141 | int ret = 0; |
475113d9 | 7142 | u64 seq; |
96398826 | 7143 | |
e050e3f0 SE |
7144 | seq = __this_cpu_read(perf_throttled_seq); |
7145 | if (seq != hwc->interrupts_seq) { | |
7146 | hwc->interrupts_seq = seq; | |
7147 | hwc->interrupts = 1; | |
7148 | } else { | |
7149 | hwc->interrupts++; | |
7150 | if (unlikely(throttle | |
7151 | && hwc->interrupts >= max_samples_per_tick)) { | |
7152 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7153 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7154 | hwc->interrupts = MAX_INTERRUPTS; |
7155 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7156 | ret = 1; |
7157 | } | |
e050e3f0 | 7158 | } |
60db5e09 | 7159 | |
cdd6c482 | 7160 | if (event->attr.freq) { |
def0a9b2 | 7161 | u64 now = perf_clock(); |
abd50713 | 7162 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7163 | |
abd50713 | 7164 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7165 | |
abd50713 | 7166 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7167 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7168 | } |
7169 | ||
475113d9 JO |
7170 | return ret; |
7171 | } | |
7172 | ||
7173 | int perf_event_account_interrupt(struct perf_event *event) | |
7174 | { | |
7175 | return __perf_event_account_interrupt(event, 1); | |
7176 | } | |
7177 | ||
7178 | /* | |
7179 | * Generic event overflow handling, sampling. | |
7180 | */ | |
7181 | ||
7182 | static int __perf_event_overflow(struct perf_event *event, | |
7183 | int throttle, struct perf_sample_data *data, | |
7184 | struct pt_regs *regs) | |
7185 | { | |
7186 | int events = atomic_read(&event->event_limit); | |
7187 | int ret = 0; | |
7188 | ||
7189 | /* | |
7190 | * Non-sampling counters might still use the PMI to fold short | |
7191 | * hardware counters, ignore those. | |
7192 | */ | |
7193 | if (unlikely(!is_sampling_event(event))) | |
7194 | return 0; | |
7195 | ||
7196 | ret = __perf_event_account_interrupt(event, throttle); | |
7197 | ||
2023b359 PZ |
7198 | /* |
7199 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7200 | * events |
2023b359 PZ |
7201 | */ |
7202 | ||
cdd6c482 IM |
7203 | event->pending_kill = POLL_IN; |
7204 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7205 | ret = 1; |
cdd6c482 | 7206 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7207 | |
7208 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7209 | } |
7210 | ||
aa6a5f3c | 7211 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7212 | |
fed66e2c | 7213 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7214 | event->pending_wakeup = 1; |
7215 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7216 | } |
7217 | ||
79f14641 | 7218 | return ret; |
f6c7d5fe PZ |
7219 | } |
7220 | ||
a8b0ca17 | 7221 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7222 | struct perf_sample_data *data, |
7223 | struct pt_regs *regs) | |
850bc73f | 7224 | { |
a8b0ca17 | 7225 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7226 | } |
7227 | ||
15dbf27c | 7228 | /* |
cdd6c482 | 7229 | * Generic software event infrastructure |
15dbf27c PZ |
7230 | */ |
7231 | ||
b28ab83c PZ |
7232 | struct swevent_htable { |
7233 | struct swevent_hlist *swevent_hlist; | |
7234 | struct mutex hlist_mutex; | |
7235 | int hlist_refcount; | |
7236 | ||
7237 | /* Recursion avoidance in each contexts */ | |
7238 | int recursion[PERF_NR_CONTEXTS]; | |
7239 | }; | |
7240 | ||
7241 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7242 | ||
7b4b6658 | 7243 | /* |
cdd6c482 IM |
7244 | * We directly increment event->count and keep a second value in |
7245 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7246 | * is kept in the range [-sample_period, 0] so that we can use the |
7247 | * sign as trigger. | |
7248 | */ | |
7249 | ||
ab573844 | 7250 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7251 | { |
cdd6c482 | 7252 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7253 | u64 period = hwc->last_period; |
7254 | u64 nr, offset; | |
7255 | s64 old, val; | |
7256 | ||
7257 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7258 | |
7259 | again: | |
e7850595 | 7260 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7261 | if (val < 0) |
7262 | return 0; | |
15dbf27c | 7263 | |
7b4b6658 PZ |
7264 | nr = div64_u64(period + val, period); |
7265 | offset = nr * period; | |
7266 | val -= offset; | |
e7850595 | 7267 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7268 | goto again; |
15dbf27c | 7269 | |
7b4b6658 | 7270 | return nr; |
15dbf27c PZ |
7271 | } |
7272 | ||
0cff784a | 7273 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7274 | struct perf_sample_data *data, |
5622f295 | 7275 | struct pt_regs *regs) |
15dbf27c | 7276 | { |
cdd6c482 | 7277 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7278 | int throttle = 0; |
15dbf27c | 7279 | |
0cff784a PZ |
7280 | if (!overflow) |
7281 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7282 | |
7b4b6658 PZ |
7283 | if (hwc->interrupts == MAX_INTERRUPTS) |
7284 | return; | |
15dbf27c | 7285 | |
7b4b6658 | 7286 | for (; overflow; overflow--) { |
a8b0ca17 | 7287 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7288 | data, regs)) { |
7b4b6658 PZ |
7289 | /* |
7290 | * We inhibit the overflow from happening when | |
7291 | * hwc->interrupts == MAX_INTERRUPTS. | |
7292 | */ | |
7293 | break; | |
7294 | } | |
cf450a73 | 7295 | throttle = 1; |
7b4b6658 | 7296 | } |
15dbf27c PZ |
7297 | } |
7298 | ||
a4eaf7f1 | 7299 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7300 | struct perf_sample_data *data, |
5622f295 | 7301 | struct pt_regs *regs) |
7b4b6658 | 7302 | { |
cdd6c482 | 7303 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7304 | |
e7850595 | 7305 | local64_add(nr, &event->count); |
d6d020e9 | 7306 | |
0cff784a PZ |
7307 | if (!regs) |
7308 | return; | |
7309 | ||
6c7e550f | 7310 | if (!is_sampling_event(event)) |
7b4b6658 | 7311 | return; |
d6d020e9 | 7312 | |
5d81e5cf AV |
7313 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7314 | data->period = nr; | |
7315 | return perf_swevent_overflow(event, 1, data, regs); | |
7316 | } else | |
7317 | data->period = event->hw.last_period; | |
7318 | ||
0cff784a | 7319 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7320 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7321 | |
e7850595 | 7322 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7323 | return; |
df1a132b | 7324 | |
a8b0ca17 | 7325 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7326 | } |
7327 | ||
f5ffe02e FW |
7328 | static int perf_exclude_event(struct perf_event *event, |
7329 | struct pt_regs *regs) | |
7330 | { | |
a4eaf7f1 | 7331 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7332 | return 1; |
a4eaf7f1 | 7333 | |
f5ffe02e FW |
7334 | if (regs) { |
7335 | if (event->attr.exclude_user && user_mode(regs)) | |
7336 | return 1; | |
7337 | ||
7338 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7339 | return 1; | |
7340 | } | |
7341 | ||
7342 | return 0; | |
7343 | } | |
7344 | ||
cdd6c482 | 7345 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7346 | enum perf_type_id type, |
6fb2915d LZ |
7347 | u32 event_id, |
7348 | struct perf_sample_data *data, | |
7349 | struct pt_regs *regs) | |
15dbf27c | 7350 | { |
cdd6c482 | 7351 | if (event->attr.type != type) |
a21ca2ca | 7352 | return 0; |
f5ffe02e | 7353 | |
cdd6c482 | 7354 | if (event->attr.config != event_id) |
15dbf27c PZ |
7355 | return 0; |
7356 | ||
f5ffe02e FW |
7357 | if (perf_exclude_event(event, regs)) |
7358 | return 0; | |
15dbf27c PZ |
7359 | |
7360 | return 1; | |
7361 | } | |
7362 | ||
76e1d904 FW |
7363 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7364 | { | |
7365 | u64 val = event_id | (type << 32); | |
7366 | ||
7367 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7368 | } | |
7369 | ||
49f135ed FW |
7370 | static inline struct hlist_head * |
7371 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7372 | { |
49f135ed FW |
7373 | u64 hash = swevent_hash(type, event_id); |
7374 | ||
7375 | return &hlist->heads[hash]; | |
7376 | } | |
76e1d904 | 7377 | |
49f135ed FW |
7378 | /* For the read side: events when they trigger */ |
7379 | static inline struct hlist_head * | |
b28ab83c | 7380 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7381 | { |
7382 | struct swevent_hlist *hlist; | |
76e1d904 | 7383 | |
b28ab83c | 7384 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7385 | if (!hlist) |
7386 | return NULL; | |
7387 | ||
49f135ed FW |
7388 | return __find_swevent_head(hlist, type, event_id); |
7389 | } | |
7390 | ||
7391 | /* For the event head insertion and removal in the hlist */ | |
7392 | static inline struct hlist_head * | |
b28ab83c | 7393 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7394 | { |
7395 | struct swevent_hlist *hlist; | |
7396 | u32 event_id = event->attr.config; | |
7397 | u64 type = event->attr.type; | |
7398 | ||
7399 | /* | |
7400 | * Event scheduling is always serialized against hlist allocation | |
7401 | * and release. Which makes the protected version suitable here. | |
7402 | * The context lock guarantees that. | |
7403 | */ | |
b28ab83c | 7404 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7405 | lockdep_is_held(&event->ctx->lock)); |
7406 | if (!hlist) | |
7407 | return NULL; | |
7408 | ||
7409 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7410 | } |
7411 | ||
7412 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7413 | u64 nr, |
76e1d904 FW |
7414 | struct perf_sample_data *data, |
7415 | struct pt_regs *regs) | |
15dbf27c | 7416 | { |
4a32fea9 | 7417 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7418 | struct perf_event *event; |
76e1d904 | 7419 | struct hlist_head *head; |
15dbf27c | 7420 | |
76e1d904 | 7421 | rcu_read_lock(); |
b28ab83c | 7422 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7423 | if (!head) |
7424 | goto end; | |
7425 | ||
b67bfe0d | 7426 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7427 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7428 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7429 | } |
76e1d904 FW |
7430 | end: |
7431 | rcu_read_unlock(); | |
15dbf27c PZ |
7432 | } |
7433 | ||
86038c5e PZI |
7434 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7435 | ||
4ed7c92d | 7436 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7437 | { |
4a32fea9 | 7438 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7439 | |
b28ab83c | 7440 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7441 | } |
645e8cc0 | 7442 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7443 | |
98b5c2c6 | 7444 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7445 | { |
4a32fea9 | 7446 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7447 | |
b28ab83c | 7448 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7449 | } |
15dbf27c | 7450 | |
86038c5e | 7451 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7452 | { |
a4234bfc | 7453 | struct perf_sample_data data; |
4ed7c92d | 7454 | |
86038c5e | 7455 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7456 | return; |
a4234bfc | 7457 | |
fd0d000b | 7458 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7459 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7460 | } |
7461 | ||
7462 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7463 | { | |
7464 | int rctx; | |
7465 | ||
7466 | preempt_disable_notrace(); | |
7467 | rctx = perf_swevent_get_recursion_context(); | |
7468 | if (unlikely(rctx < 0)) | |
7469 | goto fail; | |
7470 | ||
7471 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7472 | |
7473 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7474 | fail: |
1c024eca | 7475 | preempt_enable_notrace(); |
b8e83514 PZ |
7476 | } |
7477 | ||
cdd6c482 | 7478 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7479 | { |
15dbf27c PZ |
7480 | } |
7481 | ||
a4eaf7f1 | 7482 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7483 | { |
4a32fea9 | 7484 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7485 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7486 | struct hlist_head *head; |
7487 | ||
6c7e550f | 7488 | if (is_sampling_event(event)) { |
7b4b6658 | 7489 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7490 | perf_swevent_set_period(event); |
7b4b6658 | 7491 | } |
76e1d904 | 7492 | |
a4eaf7f1 PZ |
7493 | hwc->state = !(flags & PERF_EF_START); |
7494 | ||
b28ab83c | 7495 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7496 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7497 | return -EINVAL; |
7498 | ||
7499 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7500 | perf_event_update_userpage(event); |
76e1d904 | 7501 | |
15dbf27c PZ |
7502 | return 0; |
7503 | } | |
7504 | ||
a4eaf7f1 | 7505 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7506 | { |
76e1d904 | 7507 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7508 | } |
7509 | ||
a4eaf7f1 | 7510 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7511 | { |
a4eaf7f1 | 7512 | event->hw.state = 0; |
d6d020e9 | 7513 | } |
aa9c4c0f | 7514 | |
a4eaf7f1 | 7515 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7516 | { |
a4eaf7f1 | 7517 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7518 | } |
7519 | ||
49f135ed FW |
7520 | /* Deref the hlist from the update side */ |
7521 | static inline struct swevent_hlist * | |
b28ab83c | 7522 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7523 | { |
b28ab83c PZ |
7524 | return rcu_dereference_protected(swhash->swevent_hlist, |
7525 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7526 | } |
7527 | ||
b28ab83c | 7528 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7529 | { |
b28ab83c | 7530 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7531 | |
49f135ed | 7532 | if (!hlist) |
76e1d904 FW |
7533 | return; |
7534 | ||
70691d4a | 7535 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7536 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7537 | } |
7538 | ||
3b364d7b | 7539 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7540 | { |
b28ab83c | 7541 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7542 | |
b28ab83c | 7543 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7544 | |
b28ab83c PZ |
7545 | if (!--swhash->hlist_refcount) |
7546 | swevent_hlist_release(swhash); | |
76e1d904 | 7547 | |
b28ab83c | 7548 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7549 | } |
7550 | ||
3b364d7b | 7551 | static void swevent_hlist_put(void) |
76e1d904 FW |
7552 | { |
7553 | int cpu; | |
7554 | ||
76e1d904 | 7555 | for_each_possible_cpu(cpu) |
3b364d7b | 7556 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7557 | } |
7558 | ||
3b364d7b | 7559 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7560 | { |
b28ab83c | 7561 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7562 | int err = 0; |
7563 | ||
b28ab83c | 7564 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7565 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7566 | struct swevent_hlist *hlist; |
7567 | ||
7568 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7569 | if (!hlist) { | |
7570 | err = -ENOMEM; | |
7571 | goto exit; | |
7572 | } | |
b28ab83c | 7573 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7574 | } |
b28ab83c | 7575 | swhash->hlist_refcount++; |
9ed6060d | 7576 | exit: |
b28ab83c | 7577 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7578 | |
7579 | return err; | |
7580 | } | |
7581 | ||
3b364d7b | 7582 | static int swevent_hlist_get(void) |
76e1d904 | 7583 | { |
3b364d7b | 7584 | int err, cpu, failed_cpu; |
76e1d904 | 7585 | |
76e1d904 FW |
7586 | get_online_cpus(); |
7587 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7588 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7589 | if (err) { |
7590 | failed_cpu = cpu; | |
7591 | goto fail; | |
7592 | } | |
7593 | } | |
7594 | put_online_cpus(); | |
7595 | ||
7596 | return 0; | |
9ed6060d | 7597 | fail: |
76e1d904 FW |
7598 | for_each_possible_cpu(cpu) { |
7599 | if (cpu == failed_cpu) | |
7600 | break; | |
3b364d7b | 7601 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7602 | } |
7603 | ||
7604 | put_online_cpus(); | |
7605 | return err; | |
7606 | } | |
7607 | ||
c5905afb | 7608 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7609 | |
b0a873eb PZ |
7610 | static void sw_perf_event_destroy(struct perf_event *event) |
7611 | { | |
7612 | u64 event_id = event->attr.config; | |
95476b64 | 7613 | |
b0a873eb PZ |
7614 | WARN_ON(event->parent); |
7615 | ||
c5905afb | 7616 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7617 | swevent_hlist_put(); |
b0a873eb PZ |
7618 | } |
7619 | ||
7620 | static int perf_swevent_init(struct perf_event *event) | |
7621 | { | |
8176cced | 7622 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7623 | |
7624 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7625 | return -ENOENT; | |
7626 | ||
2481c5fa SE |
7627 | /* |
7628 | * no branch sampling for software events | |
7629 | */ | |
7630 | if (has_branch_stack(event)) | |
7631 | return -EOPNOTSUPP; | |
7632 | ||
b0a873eb PZ |
7633 | switch (event_id) { |
7634 | case PERF_COUNT_SW_CPU_CLOCK: | |
7635 | case PERF_COUNT_SW_TASK_CLOCK: | |
7636 | return -ENOENT; | |
7637 | ||
7638 | default: | |
7639 | break; | |
7640 | } | |
7641 | ||
ce677831 | 7642 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7643 | return -ENOENT; |
7644 | ||
7645 | if (!event->parent) { | |
7646 | int err; | |
7647 | ||
3b364d7b | 7648 | err = swevent_hlist_get(); |
b0a873eb PZ |
7649 | if (err) |
7650 | return err; | |
7651 | ||
c5905afb | 7652 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7653 | event->destroy = sw_perf_event_destroy; |
7654 | } | |
7655 | ||
7656 | return 0; | |
7657 | } | |
7658 | ||
7659 | static struct pmu perf_swevent = { | |
89a1e187 | 7660 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7661 | |
34f43927 PZ |
7662 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7663 | ||
b0a873eb | 7664 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7665 | .add = perf_swevent_add, |
7666 | .del = perf_swevent_del, | |
7667 | .start = perf_swevent_start, | |
7668 | .stop = perf_swevent_stop, | |
1c024eca | 7669 | .read = perf_swevent_read, |
1c024eca PZ |
7670 | }; |
7671 | ||
b0a873eb PZ |
7672 | #ifdef CONFIG_EVENT_TRACING |
7673 | ||
1c024eca PZ |
7674 | static int perf_tp_filter_match(struct perf_event *event, |
7675 | struct perf_sample_data *data) | |
7676 | { | |
7e3f977e | 7677 | void *record = data->raw->frag.data; |
1c024eca | 7678 | |
b71b437e PZ |
7679 | /* only top level events have filters set */ |
7680 | if (event->parent) | |
7681 | event = event->parent; | |
7682 | ||
1c024eca PZ |
7683 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7684 | return 1; | |
7685 | return 0; | |
7686 | } | |
7687 | ||
7688 | static int perf_tp_event_match(struct perf_event *event, | |
7689 | struct perf_sample_data *data, | |
7690 | struct pt_regs *regs) | |
7691 | { | |
a0f7d0f7 FW |
7692 | if (event->hw.state & PERF_HES_STOPPED) |
7693 | return 0; | |
580d607c PZ |
7694 | /* |
7695 | * All tracepoints are from kernel-space. | |
7696 | */ | |
7697 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7698 | return 0; |
7699 | ||
7700 | if (!perf_tp_filter_match(event, data)) | |
7701 | return 0; | |
7702 | ||
7703 | return 1; | |
7704 | } | |
7705 | ||
85b67bcb AS |
7706 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7707 | struct trace_event_call *call, u64 count, | |
7708 | struct pt_regs *regs, struct hlist_head *head, | |
7709 | struct task_struct *task) | |
7710 | { | |
7711 | struct bpf_prog *prog = call->prog; | |
7712 | ||
7713 | if (prog) { | |
7714 | *(struct pt_regs **)raw_data = regs; | |
7715 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7716 | perf_swevent_put_recursion_context(rctx); | |
7717 | return; | |
7718 | } | |
7719 | } | |
7720 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7721 | rctx, task); | |
7722 | } | |
7723 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7724 | ||
1e1dcd93 | 7725 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7726 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7727 | struct task_struct *task) | |
95476b64 FW |
7728 | { |
7729 | struct perf_sample_data data; | |
1c024eca | 7730 | struct perf_event *event; |
1c024eca | 7731 | |
95476b64 | 7732 | struct perf_raw_record raw = { |
7e3f977e DB |
7733 | .frag = { |
7734 | .size = entry_size, | |
7735 | .data = record, | |
7736 | }, | |
95476b64 FW |
7737 | }; |
7738 | ||
1e1dcd93 | 7739 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7740 | data.raw = &raw; |
7741 | ||
1e1dcd93 AS |
7742 | perf_trace_buf_update(record, event_type); |
7743 | ||
b67bfe0d | 7744 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7745 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7746 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7747 | } |
ecc55f84 | 7748 | |
e6dab5ff AV |
7749 | /* |
7750 | * If we got specified a target task, also iterate its context and | |
7751 | * deliver this event there too. | |
7752 | */ | |
7753 | if (task && task != current) { | |
7754 | struct perf_event_context *ctx; | |
7755 | struct trace_entry *entry = record; | |
7756 | ||
7757 | rcu_read_lock(); | |
7758 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7759 | if (!ctx) | |
7760 | goto unlock; | |
7761 | ||
7762 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7763 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7764 | continue; | |
7765 | if (event->attr.config != entry->type) | |
7766 | continue; | |
7767 | if (perf_tp_event_match(event, &data, regs)) | |
7768 | perf_swevent_event(event, count, &data, regs); | |
7769 | } | |
7770 | unlock: | |
7771 | rcu_read_unlock(); | |
7772 | } | |
7773 | ||
ecc55f84 | 7774 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7775 | } |
7776 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7777 | ||
cdd6c482 | 7778 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7779 | { |
1c024eca | 7780 | perf_trace_destroy(event); |
e077df4f PZ |
7781 | } |
7782 | ||
b0a873eb | 7783 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7784 | { |
76e1d904 FW |
7785 | int err; |
7786 | ||
b0a873eb PZ |
7787 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7788 | return -ENOENT; | |
7789 | ||
2481c5fa SE |
7790 | /* |
7791 | * no branch sampling for tracepoint events | |
7792 | */ | |
7793 | if (has_branch_stack(event)) | |
7794 | return -EOPNOTSUPP; | |
7795 | ||
1c024eca PZ |
7796 | err = perf_trace_init(event); |
7797 | if (err) | |
b0a873eb | 7798 | return err; |
e077df4f | 7799 | |
cdd6c482 | 7800 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7801 | |
b0a873eb PZ |
7802 | return 0; |
7803 | } | |
7804 | ||
7805 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7806 | .task_ctx_nr = perf_sw_context, |
7807 | ||
b0a873eb | 7808 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7809 | .add = perf_trace_add, |
7810 | .del = perf_trace_del, | |
7811 | .start = perf_swevent_start, | |
7812 | .stop = perf_swevent_stop, | |
b0a873eb | 7813 | .read = perf_swevent_read, |
b0a873eb PZ |
7814 | }; |
7815 | ||
7816 | static inline void perf_tp_register(void) | |
7817 | { | |
2e80a82a | 7818 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7819 | } |
6fb2915d | 7820 | |
6fb2915d LZ |
7821 | static void perf_event_free_filter(struct perf_event *event) |
7822 | { | |
7823 | ftrace_profile_free_filter(event); | |
7824 | } | |
7825 | ||
aa6a5f3c AS |
7826 | #ifdef CONFIG_BPF_SYSCALL |
7827 | static void bpf_overflow_handler(struct perf_event *event, | |
7828 | struct perf_sample_data *data, | |
7829 | struct pt_regs *regs) | |
7830 | { | |
7831 | struct bpf_perf_event_data_kern ctx = { | |
7832 | .data = data, | |
7833 | .regs = regs, | |
7834 | }; | |
7835 | int ret = 0; | |
7836 | ||
7837 | preempt_disable(); | |
7838 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
7839 | goto out; | |
7840 | rcu_read_lock(); | |
88575199 | 7841 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
7842 | rcu_read_unlock(); |
7843 | out: | |
7844 | __this_cpu_dec(bpf_prog_active); | |
7845 | preempt_enable(); | |
7846 | if (!ret) | |
7847 | return; | |
7848 | ||
7849 | event->orig_overflow_handler(event, data, regs); | |
7850 | } | |
7851 | ||
7852 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7853 | { | |
7854 | struct bpf_prog *prog; | |
7855 | ||
7856 | if (event->overflow_handler_context) | |
7857 | /* hw breakpoint or kernel counter */ | |
7858 | return -EINVAL; | |
7859 | ||
7860 | if (event->prog) | |
7861 | return -EEXIST; | |
7862 | ||
7863 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
7864 | if (IS_ERR(prog)) | |
7865 | return PTR_ERR(prog); | |
7866 | ||
7867 | event->prog = prog; | |
7868 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
7869 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
7870 | return 0; | |
7871 | } | |
7872 | ||
7873 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7874 | { | |
7875 | struct bpf_prog *prog = event->prog; | |
7876 | ||
7877 | if (!prog) | |
7878 | return; | |
7879 | ||
7880 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
7881 | event->prog = NULL; | |
7882 | bpf_prog_put(prog); | |
7883 | } | |
7884 | #else | |
7885 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7886 | { | |
7887 | return -EOPNOTSUPP; | |
7888 | } | |
7889 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7890 | { | |
7891 | } | |
7892 | #endif | |
7893 | ||
2541517c AS |
7894 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7895 | { | |
98b5c2c6 | 7896 | bool is_kprobe, is_tracepoint; |
2541517c AS |
7897 | struct bpf_prog *prog; |
7898 | ||
aa6a5f3c AS |
7899 | if (event->attr.type == PERF_TYPE_HARDWARE || |
7900 | event->attr.type == PERF_TYPE_SOFTWARE) | |
7901 | return perf_event_set_bpf_handler(event, prog_fd); | |
7902 | ||
2541517c AS |
7903 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7904 | return -EINVAL; | |
7905 | ||
7906 | if (event->tp_event->prog) | |
7907 | return -EEXIST; | |
7908 | ||
98b5c2c6 AS |
7909 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
7910 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
7911 | if (!is_kprobe && !is_tracepoint) | |
7912 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
7913 | return -EINVAL; |
7914 | ||
7915 | prog = bpf_prog_get(prog_fd); | |
7916 | if (IS_ERR(prog)) | |
7917 | return PTR_ERR(prog); | |
7918 | ||
98b5c2c6 AS |
7919 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
7920 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
7921 | /* valid fd, but invalid bpf program type */ |
7922 | bpf_prog_put(prog); | |
7923 | return -EINVAL; | |
7924 | } | |
7925 | ||
32bbe007 AS |
7926 | if (is_tracepoint) { |
7927 | int off = trace_event_get_offsets(event->tp_event); | |
7928 | ||
7929 | if (prog->aux->max_ctx_offset > off) { | |
7930 | bpf_prog_put(prog); | |
7931 | return -EACCES; | |
7932 | } | |
7933 | } | |
2541517c AS |
7934 | event->tp_event->prog = prog; |
7935 | ||
7936 | return 0; | |
7937 | } | |
7938 | ||
7939 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7940 | { | |
7941 | struct bpf_prog *prog; | |
7942 | ||
aa6a5f3c AS |
7943 | perf_event_free_bpf_handler(event); |
7944 | ||
2541517c AS |
7945 | if (!event->tp_event) |
7946 | return; | |
7947 | ||
7948 | prog = event->tp_event->prog; | |
7949 | if (prog) { | |
7950 | event->tp_event->prog = NULL; | |
1aacde3d | 7951 | bpf_prog_put(prog); |
2541517c AS |
7952 | } |
7953 | } | |
7954 | ||
e077df4f | 7955 | #else |
6fb2915d | 7956 | |
b0a873eb | 7957 | static inline void perf_tp_register(void) |
e077df4f | 7958 | { |
e077df4f | 7959 | } |
6fb2915d | 7960 | |
6fb2915d LZ |
7961 | static void perf_event_free_filter(struct perf_event *event) |
7962 | { | |
7963 | } | |
7964 | ||
2541517c AS |
7965 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7966 | { | |
7967 | return -ENOENT; | |
7968 | } | |
7969 | ||
7970 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7971 | { | |
7972 | } | |
07b139c8 | 7973 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7974 | |
24f1e32c | 7975 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7976 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7977 | { |
f5ffe02e FW |
7978 | struct perf_sample_data sample; |
7979 | struct pt_regs *regs = data; | |
7980 | ||
fd0d000b | 7981 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7982 | |
a4eaf7f1 | 7983 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7984 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7985 | } |
7986 | #endif | |
7987 | ||
375637bc AS |
7988 | /* |
7989 | * Allocate a new address filter | |
7990 | */ | |
7991 | static struct perf_addr_filter * | |
7992 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
7993 | { | |
7994 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
7995 | struct perf_addr_filter *filter; | |
7996 | ||
7997 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
7998 | if (!filter) | |
7999 | return NULL; | |
8000 | ||
8001 | INIT_LIST_HEAD(&filter->entry); | |
8002 | list_add_tail(&filter->entry, filters); | |
8003 | ||
8004 | return filter; | |
8005 | } | |
8006 | ||
8007 | static void free_filters_list(struct list_head *filters) | |
8008 | { | |
8009 | struct perf_addr_filter *filter, *iter; | |
8010 | ||
8011 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
8012 | if (filter->inode) | |
8013 | iput(filter->inode); | |
8014 | list_del(&filter->entry); | |
8015 | kfree(filter); | |
8016 | } | |
8017 | } | |
8018 | ||
8019 | /* | |
8020 | * Free existing address filters and optionally install new ones | |
8021 | */ | |
8022 | static void perf_addr_filters_splice(struct perf_event *event, | |
8023 | struct list_head *head) | |
8024 | { | |
8025 | unsigned long flags; | |
8026 | LIST_HEAD(list); | |
8027 | ||
8028 | if (!has_addr_filter(event)) | |
8029 | return; | |
8030 | ||
8031 | /* don't bother with children, they don't have their own filters */ | |
8032 | if (event->parent) | |
8033 | return; | |
8034 | ||
8035 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
8036 | ||
8037 | list_splice_init(&event->addr_filters.list, &list); | |
8038 | if (head) | |
8039 | list_splice(head, &event->addr_filters.list); | |
8040 | ||
8041 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
8042 | ||
8043 | free_filters_list(&list); | |
8044 | } | |
8045 | ||
8046 | /* | |
8047 | * Scan through mm's vmas and see if one of them matches the | |
8048 | * @filter; if so, adjust filter's address range. | |
8049 | * Called with mm::mmap_sem down for reading. | |
8050 | */ | |
8051 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8052 | struct mm_struct *mm) | |
8053 | { | |
8054 | struct vm_area_struct *vma; | |
8055 | ||
8056 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8057 | struct file *file = vma->vm_file; | |
8058 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8059 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8060 | ||
8061 | if (!file) | |
8062 | continue; | |
8063 | ||
8064 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8065 | continue; | |
8066 | ||
8067 | return vma->vm_start; | |
8068 | } | |
8069 | ||
8070 | return 0; | |
8071 | } | |
8072 | ||
8073 | /* | |
8074 | * Update event's address range filters based on the | |
8075 | * task's existing mappings, if any. | |
8076 | */ | |
8077 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8078 | { | |
8079 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8080 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8081 | struct perf_addr_filter *filter; | |
8082 | struct mm_struct *mm = NULL; | |
8083 | unsigned int count = 0; | |
8084 | unsigned long flags; | |
8085 | ||
8086 | /* | |
8087 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8088 | * will stop on the parent's child_mutex that our caller is also holding | |
8089 | */ | |
8090 | if (task == TASK_TOMBSTONE) | |
8091 | return; | |
8092 | ||
8093 | mm = get_task_mm(event->ctx->task); | |
8094 | if (!mm) | |
8095 | goto restart; | |
8096 | ||
8097 | down_read(&mm->mmap_sem); | |
8098 | ||
8099 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8100 | list_for_each_entry(filter, &ifh->list, entry) { | |
8101 | event->addr_filters_offs[count] = 0; | |
8102 | ||
99f5bc9b MP |
8103 | /* |
8104 | * Adjust base offset if the filter is associated to a binary | |
8105 | * that needs to be mapped: | |
8106 | */ | |
8107 | if (filter->inode) | |
375637bc AS |
8108 | event->addr_filters_offs[count] = |
8109 | perf_addr_filter_apply(filter, mm); | |
8110 | ||
8111 | count++; | |
8112 | } | |
8113 | ||
8114 | event->addr_filters_gen++; | |
8115 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8116 | ||
8117 | up_read(&mm->mmap_sem); | |
8118 | ||
8119 | mmput(mm); | |
8120 | ||
8121 | restart: | |
767ae086 | 8122 | perf_event_stop(event, 1); |
375637bc AS |
8123 | } |
8124 | ||
8125 | /* | |
8126 | * Address range filtering: limiting the data to certain | |
8127 | * instruction address ranges. Filters are ioctl()ed to us from | |
8128 | * userspace as ascii strings. | |
8129 | * | |
8130 | * Filter string format: | |
8131 | * | |
8132 | * ACTION RANGE_SPEC | |
8133 | * where ACTION is one of the | |
8134 | * * "filter": limit the trace to this region | |
8135 | * * "start": start tracing from this address | |
8136 | * * "stop": stop tracing at this address/region; | |
8137 | * RANGE_SPEC is | |
8138 | * * for kernel addresses: <start address>[/<size>] | |
8139 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8140 | * | |
8141 | * if <size> is not specified, the range is treated as a single address. | |
8142 | */ | |
8143 | enum { | |
e96271f3 | 8144 | IF_ACT_NONE = -1, |
375637bc AS |
8145 | IF_ACT_FILTER, |
8146 | IF_ACT_START, | |
8147 | IF_ACT_STOP, | |
8148 | IF_SRC_FILE, | |
8149 | IF_SRC_KERNEL, | |
8150 | IF_SRC_FILEADDR, | |
8151 | IF_SRC_KERNELADDR, | |
8152 | }; | |
8153 | ||
8154 | enum { | |
8155 | IF_STATE_ACTION = 0, | |
8156 | IF_STATE_SOURCE, | |
8157 | IF_STATE_END, | |
8158 | }; | |
8159 | ||
8160 | static const match_table_t if_tokens = { | |
8161 | { IF_ACT_FILTER, "filter" }, | |
8162 | { IF_ACT_START, "start" }, | |
8163 | { IF_ACT_STOP, "stop" }, | |
8164 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8165 | { IF_SRC_KERNEL, "%u/%u" }, | |
8166 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8167 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8168 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8169 | }; |
8170 | ||
8171 | /* | |
8172 | * Address filter string parser | |
8173 | */ | |
8174 | static int | |
8175 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8176 | struct list_head *filters) | |
8177 | { | |
8178 | struct perf_addr_filter *filter = NULL; | |
8179 | char *start, *orig, *filename = NULL; | |
8180 | struct path path; | |
8181 | substring_t args[MAX_OPT_ARGS]; | |
8182 | int state = IF_STATE_ACTION, token; | |
8183 | unsigned int kernel = 0; | |
8184 | int ret = -EINVAL; | |
8185 | ||
8186 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8187 | if (!fstr) | |
8188 | return -ENOMEM; | |
8189 | ||
8190 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8191 | ret = -EINVAL; | |
8192 | ||
8193 | if (!*start) | |
8194 | continue; | |
8195 | ||
8196 | /* filter definition begins */ | |
8197 | if (state == IF_STATE_ACTION) { | |
8198 | filter = perf_addr_filter_new(event, filters); | |
8199 | if (!filter) | |
8200 | goto fail; | |
8201 | } | |
8202 | ||
8203 | token = match_token(start, if_tokens, args); | |
8204 | switch (token) { | |
8205 | case IF_ACT_FILTER: | |
8206 | case IF_ACT_START: | |
8207 | filter->filter = 1; | |
8208 | ||
8209 | case IF_ACT_STOP: | |
8210 | if (state != IF_STATE_ACTION) | |
8211 | goto fail; | |
8212 | ||
8213 | state = IF_STATE_SOURCE; | |
8214 | break; | |
8215 | ||
8216 | case IF_SRC_KERNELADDR: | |
8217 | case IF_SRC_KERNEL: | |
8218 | kernel = 1; | |
8219 | ||
8220 | case IF_SRC_FILEADDR: | |
8221 | case IF_SRC_FILE: | |
8222 | if (state != IF_STATE_SOURCE) | |
8223 | goto fail; | |
8224 | ||
8225 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8226 | filter->range = 1; | |
8227 | ||
8228 | *args[0].to = 0; | |
8229 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8230 | if (ret) | |
8231 | goto fail; | |
8232 | ||
8233 | if (filter->range) { | |
8234 | *args[1].to = 0; | |
8235 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8236 | if (ret) | |
8237 | goto fail; | |
8238 | } | |
8239 | ||
4059ffd0 MP |
8240 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8241 | int fpos = filter->range ? 2 : 1; | |
8242 | ||
8243 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8244 | if (!filename) { |
8245 | ret = -ENOMEM; | |
8246 | goto fail; | |
8247 | } | |
8248 | } | |
8249 | ||
8250 | state = IF_STATE_END; | |
8251 | break; | |
8252 | ||
8253 | default: | |
8254 | goto fail; | |
8255 | } | |
8256 | ||
8257 | /* | |
8258 | * Filter definition is fully parsed, validate and install it. | |
8259 | * Make sure that it doesn't contradict itself or the event's | |
8260 | * attribute. | |
8261 | */ | |
8262 | if (state == IF_STATE_END) { | |
8263 | if (kernel && event->attr.exclude_kernel) | |
8264 | goto fail; | |
8265 | ||
8266 | if (!kernel) { | |
8267 | if (!filename) | |
8268 | goto fail; | |
8269 | ||
8270 | /* look up the path and grab its inode */ | |
8271 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8272 | if (ret) | |
8273 | goto fail_free_name; | |
8274 | ||
8275 | filter->inode = igrab(d_inode(path.dentry)); | |
8276 | path_put(&path); | |
8277 | kfree(filename); | |
8278 | filename = NULL; | |
8279 | ||
8280 | ret = -EINVAL; | |
8281 | if (!filter->inode || | |
8282 | !S_ISREG(filter->inode->i_mode)) | |
8283 | /* free_filters_list() will iput() */ | |
8284 | goto fail; | |
8285 | } | |
8286 | ||
8287 | /* ready to consume more filters */ | |
8288 | state = IF_STATE_ACTION; | |
8289 | filter = NULL; | |
8290 | } | |
8291 | } | |
8292 | ||
8293 | if (state != IF_STATE_ACTION) | |
8294 | goto fail; | |
8295 | ||
8296 | kfree(orig); | |
8297 | ||
8298 | return 0; | |
8299 | ||
8300 | fail_free_name: | |
8301 | kfree(filename); | |
8302 | fail: | |
8303 | free_filters_list(filters); | |
8304 | kfree(orig); | |
8305 | ||
8306 | return ret; | |
8307 | } | |
8308 | ||
8309 | static int | |
8310 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8311 | { | |
8312 | LIST_HEAD(filters); | |
8313 | int ret; | |
8314 | ||
8315 | /* | |
8316 | * Since this is called in perf_ioctl() path, we're already holding | |
8317 | * ctx::mutex. | |
8318 | */ | |
8319 | lockdep_assert_held(&event->ctx->mutex); | |
8320 | ||
8321 | if (WARN_ON_ONCE(event->parent)) | |
8322 | return -EINVAL; | |
8323 | ||
8324 | /* | |
8325 | * For now, we only support filtering in per-task events; doing so | |
8326 | * for CPU-wide events requires additional context switching trickery, | |
8327 | * since same object code will be mapped at different virtual | |
8328 | * addresses in different processes. | |
8329 | */ | |
8330 | if (!event->ctx->task) | |
8331 | return -EOPNOTSUPP; | |
8332 | ||
8333 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); | |
8334 | if (ret) | |
8335 | return ret; | |
8336 | ||
8337 | ret = event->pmu->addr_filters_validate(&filters); | |
8338 | if (ret) { | |
8339 | free_filters_list(&filters); | |
8340 | return ret; | |
8341 | } | |
8342 | ||
8343 | /* remove existing filters, if any */ | |
8344 | perf_addr_filters_splice(event, &filters); | |
8345 | ||
8346 | /* install new filters */ | |
8347 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8348 | ||
8349 | return ret; | |
8350 | } | |
8351 | ||
c796bbbe AS |
8352 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8353 | { | |
8354 | char *filter_str; | |
8355 | int ret = -EINVAL; | |
8356 | ||
375637bc AS |
8357 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8358 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8359 | !has_addr_filter(event)) | |
c796bbbe AS |
8360 | return -EINVAL; |
8361 | ||
8362 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8363 | if (IS_ERR(filter_str)) | |
8364 | return PTR_ERR(filter_str); | |
8365 | ||
8366 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8367 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8368 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8369 | filter_str); | |
375637bc AS |
8370 | else if (has_addr_filter(event)) |
8371 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8372 | |
8373 | kfree(filter_str); | |
8374 | return ret; | |
8375 | } | |
8376 | ||
b0a873eb PZ |
8377 | /* |
8378 | * hrtimer based swevent callback | |
8379 | */ | |
f29ac756 | 8380 | |
b0a873eb | 8381 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8382 | { |
b0a873eb PZ |
8383 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8384 | struct perf_sample_data data; | |
8385 | struct pt_regs *regs; | |
8386 | struct perf_event *event; | |
8387 | u64 period; | |
f29ac756 | 8388 | |
b0a873eb | 8389 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8390 | |
8391 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8392 | return HRTIMER_NORESTART; | |
8393 | ||
b0a873eb | 8394 | event->pmu->read(event); |
f344011c | 8395 | |
fd0d000b | 8396 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8397 | regs = get_irq_regs(); |
8398 | ||
8399 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8400 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8401 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8402 | ret = HRTIMER_NORESTART; |
8403 | } | |
24f1e32c | 8404 | |
b0a873eb PZ |
8405 | period = max_t(u64, 10000, event->hw.sample_period); |
8406 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8407 | |
b0a873eb | 8408 | return ret; |
f29ac756 PZ |
8409 | } |
8410 | ||
b0a873eb | 8411 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8412 | { |
b0a873eb | 8413 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8414 | s64 period; |
8415 | ||
8416 | if (!is_sampling_event(event)) | |
8417 | return; | |
f5ffe02e | 8418 | |
5d508e82 FBH |
8419 | period = local64_read(&hwc->period_left); |
8420 | if (period) { | |
8421 | if (period < 0) | |
8422 | period = 10000; | |
fa407f35 | 8423 | |
5d508e82 FBH |
8424 | local64_set(&hwc->period_left, 0); |
8425 | } else { | |
8426 | period = max_t(u64, 10000, hwc->sample_period); | |
8427 | } | |
3497d206 TG |
8428 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8429 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8430 | } |
b0a873eb PZ |
8431 | |
8432 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8433 | { |
b0a873eb PZ |
8434 | struct hw_perf_event *hwc = &event->hw; |
8435 | ||
6c7e550f | 8436 | if (is_sampling_event(event)) { |
b0a873eb | 8437 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8438 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8439 | |
8440 | hrtimer_cancel(&hwc->hrtimer); | |
8441 | } | |
24f1e32c FW |
8442 | } |
8443 | ||
ba3dd36c PZ |
8444 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8445 | { | |
8446 | struct hw_perf_event *hwc = &event->hw; | |
8447 | ||
8448 | if (!is_sampling_event(event)) | |
8449 | return; | |
8450 | ||
8451 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8452 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8453 | ||
8454 | /* | |
8455 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8456 | * mapping and avoid the whole period adjust feedback stuff. | |
8457 | */ | |
8458 | if (event->attr.freq) { | |
8459 | long freq = event->attr.sample_freq; | |
8460 | ||
8461 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8462 | hwc->sample_period = event->attr.sample_period; | |
8463 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8464 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8465 | event->attr.freq = 0; |
8466 | } | |
8467 | } | |
8468 | ||
b0a873eb PZ |
8469 | /* |
8470 | * Software event: cpu wall time clock | |
8471 | */ | |
8472 | ||
8473 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8474 | { |
b0a873eb PZ |
8475 | s64 prev; |
8476 | u64 now; | |
8477 | ||
a4eaf7f1 | 8478 | now = local_clock(); |
b0a873eb PZ |
8479 | prev = local64_xchg(&event->hw.prev_count, now); |
8480 | local64_add(now - prev, &event->count); | |
24f1e32c | 8481 | } |
24f1e32c | 8482 | |
a4eaf7f1 | 8483 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8484 | { |
a4eaf7f1 | 8485 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8486 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8487 | } |
8488 | ||
a4eaf7f1 | 8489 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8490 | { |
b0a873eb PZ |
8491 | perf_swevent_cancel_hrtimer(event); |
8492 | cpu_clock_event_update(event); | |
8493 | } | |
f29ac756 | 8494 | |
a4eaf7f1 PZ |
8495 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8496 | { | |
8497 | if (flags & PERF_EF_START) | |
8498 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8499 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8500 | |
8501 | return 0; | |
8502 | } | |
8503 | ||
8504 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8505 | { | |
8506 | cpu_clock_event_stop(event, flags); | |
8507 | } | |
8508 | ||
b0a873eb PZ |
8509 | static void cpu_clock_event_read(struct perf_event *event) |
8510 | { | |
8511 | cpu_clock_event_update(event); | |
8512 | } | |
f344011c | 8513 | |
b0a873eb PZ |
8514 | static int cpu_clock_event_init(struct perf_event *event) |
8515 | { | |
8516 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8517 | return -ENOENT; | |
8518 | ||
8519 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8520 | return -ENOENT; | |
8521 | ||
2481c5fa SE |
8522 | /* |
8523 | * no branch sampling for software events | |
8524 | */ | |
8525 | if (has_branch_stack(event)) | |
8526 | return -EOPNOTSUPP; | |
8527 | ||
ba3dd36c PZ |
8528 | perf_swevent_init_hrtimer(event); |
8529 | ||
b0a873eb | 8530 | return 0; |
f29ac756 PZ |
8531 | } |
8532 | ||
b0a873eb | 8533 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8534 | .task_ctx_nr = perf_sw_context, |
8535 | ||
34f43927 PZ |
8536 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8537 | ||
b0a873eb | 8538 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8539 | .add = cpu_clock_event_add, |
8540 | .del = cpu_clock_event_del, | |
8541 | .start = cpu_clock_event_start, | |
8542 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8543 | .read = cpu_clock_event_read, |
8544 | }; | |
8545 | ||
8546 | /* | |
8547 | * Software event: task time clock | |
8548 | */ | |
8549 | ||
8550 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8551 | { |
b0a873eb PZ |
8552 | u64 prev; |
8553 | s64 delta; | |
5c92d124 | 8554 | |
b0a873eb PZ |
8555 | prev = local64_xchg(&event->hw.prev_count, now); |
8556 | delta = now - prev; | |
8557 | local64_add(delta, &event->count); | |
8558 | } | |
5c92d124 | 8559 | |
a4eaf7f1 | 8560 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8561 | { |
a4eaf7f1 | 8562 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8563 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8564 | } |
8565 | ||
a4eaf7f1 | 8566 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8567 | { |
8568 | perf_swevent_cancel_hrtimer(event); | |
8569 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8570 | } |
8571 | ||
8572 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8573 | { | |
8574 | if (flags & PERF_EF_START) | |
8575 | task_clock_event_start(event, flags); | |
6a694a60 | 8576 | perf_event_update_userpage(event); |
b0a873eb | 8577 | |
a4eaf7f1 PZ |
8578 | return 0; |
8579 | } | |
8580 | ||
8581 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8582 | { | |
8583 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8584 | } |
8585 | ||
8586 | static void task_clock_event_read(struct perf_event *event) | |
8587 | { | |
768a06e2 PZ |
8588 | u64 now = perf_clock(); |
8589 | u64 delta = now - event->ctx->timestamp; | |
8590 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8591 | |
8592 | task_clock_event_update(event, time); | |
8593 | } | |
8594 | ||
8595 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8596 | { |
b0a873eb PZ |
8597 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8598 | return -ENOENT; | |
8599 | ||
8600 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8601 | return -ENOENT; | |
8602 | ||
2481c5fa SE |
8603 | /* |
8604 | * no branch sampling for software events | |
8605 | */ | |
8606 | if (has_branch_stack(event)) | |
8607 | return -EOPNOTSUPP; | |
8608 | ||
ba3dd36c PZ |
8609 | perf_swevent_init_hrtimer(event); |
8610 | ||
b0a873eb | 8611 | return 0; |
6fb2915d LZ |
8612 | } |
8613 | ||
b0a873eb | 8614 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8615 | .task_ctx_nr = perf_sw_context, |
8616 | ||
34f43927 PZ |
8617 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8618 | ||
b0a873eb | 8619 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8620 | .add = task_clock_event_add, |
8621 | .del = task_clock_event_del, | |
8622 | .start = task_clock_event_start, | |
8623 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8624 | .read = task_clock_event_read, |
8625 | }; | |
6fb2915d | 8626 | |
ad5133b7 | 8627 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8628 | { |
e077df4f | 8629 | } |
6fb2915d | 8630 | |
fbbe0701 SB |
8631 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8632 | { | |
8633 | } | |
8634 | ||
ad5133b7 | 8635 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8636 | { |
ad5133b7 | 8637 | return 0; |
6fb2915d LZ |
8638 | } |
8639 | ||
18ab2cd3 | 8640 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8641 | |
8642 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8643 | { |
fbbe0701 SB |
8644 | __this_cpu_write(nop_txn_flags, flags); |
8645 | ||
8646 | if (flags & ~PERF_PMU_TXN_ADD) | |
8647 | return; | |
8648 | ||
ad5133b7 | 8649 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8650 | } |
8651 | ||
ad5133b7 PZ |
8652 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8653 | { | |
fbbe0701 SB |
8654 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8655 | ||
8656 | __this_cpu_write(nop_txn_flags, 0); | |
8657 | ||
8658 | if (flags & ~PERF_PMU_TXN_ADD) | |
8659 | return 0; | |
8660 | ||
ad5133b7 PZ |
8661 | perf_pmu_enable(pmu); |
8662 | return 0; | |
8663 | } | |
e077df4f | 8664 | |
ad5133b7 | 8665 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8666 | { |
fbbe0701 SB |
8667 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8668 | ||
8669 | __this_cpu_write(nop_txn_flags, 0); | |
8670 | ||
8671 | if (flags & ~PERF_PMU_TXN_ADD) | |
8672 | return; | |
8673 | ||
ad5133b7 | 8674 | perf_pmu_enable(pmu); |
24f1e32c FW |
8675 | } |
8676 | ||
35edc2a5 PZ |
8677 | static int perf_event_idx_default(struct perf_event *event) |
8678 | { | |
c719f560 | 8679 | return 0; |
35edc2a5 PZ |
8680 | } |
8681 | ||
8dc85d54 PZ |
8682 | /* |
8683 | * Ensures all contexts with the same task_ctx_nr have the same | |
8684 | * pmu_cpu_context too. | |
8685 | */ | |
9e317041 | 8686 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8687 | { |
8dc85d54 | 8688 | struct pmu *pmu; |
b326e956 | 8689 | |
8dc85d54 PZ |
8690 | if (ctxn < 0) |
8691 | return NULL; | |
24f1e32c | 8692 | |
8dc85d54 PZ |
8693 | list_for_each_entry(pmu, &pmus, entry) { |
8694 | if (pmu->task_ctx_nr == ctxn) | |
8695 | return pmu->pmu_cpu_context; | |
8696 | } | |
24f1e32c | 8697 | |
8dc85d54 | 8698 | return NULL; |
24f1e32c FW |
8699 | } |
8700 | ||
51676957 PZ |
8701 | static void free_pmu_context(struct pmu *pmu) |
8702 | { | |
8dc85d54 | 8703 | mutex_lock(&pmus_lock); |
51676957 | 8704 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 | 8705 | mutex_unlock(&pmus_lock); |
24f1e32c | 8706 | } |
6e855cd4 AS |
8707 | |
8708 | /* | |
8709 | * Let userspace know that this PMU supports address range filtering: | |
8710 | */ | |
8711 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8712 | struct device_attribute *attr, | |
8713 | char *page) | |
8714 | { | |
8715 | struct pmu *pmu = dev_get_drvdata(dev); | |
8716 | ||
8717 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8718 | } | |
8719 | DEVICE_ATTR_RO(nr_addr_filters); | |
8720 | ||
2e80a82a | 8721 | static struct idr pmu_idr; |
d6d020e9 | 8722 | |
abe43400 PZ |
8723 | static ssize_t |
8724 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8725 | { | |
8726 | struct pmu *pmu = dev_get_drvdata(dev); | |
8727 | ||
8728 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8729 | } | |
90826ca7 | 8730 | static DEVICE_ATTR_RO(type); |
abe43400 | 8731 | |
62b85639 SE |
8732 | static ssize_t |
8733 | perf_event_mux_interval_ms_show(struct device *dev, | |
8734 | struct device_attribute *attr, | |
8735 | char *page) | |
8736 | { | |
8737 | struct pmu *pmu = dev_get_drvdata(dev); | |
8738 | ||
8739 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8740 | } | |
8741 | ||
272325c4 PZ |
8742 | static DEFINE_MUTEX(mux_interval_mutex); |
8743 | ||
62b85639 SE |
8744 | static ssize_t |
8745 | perf_event_mux_interval_ms_store(struct device *dev, | |
8746 | struct device_attribute *attr, | |
8747 | const char *buf, size_t count) | |
8748 | { | |
8749 | struct pmu *pmu = dev_get_drvdata(dev); | |
8750 | int timer, cpu, ret; | |
8751 | ||
8752 | ret = kstrtoint(buf, 0, &timer); | |
8753 | if (ret) | |
8754 | return ret; | |
8755 | ||
8756 | if (timer < 1) | |
8757 | return -EINVAL; | |
8758 | ||
8759 | /* same value, noting to do */ | |
8760 | if (timer == pmu->hrtimer_interval_ms) | |
8761 | return count; | |
8762 | ||
272325c4 | 8763 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8764 | pmu->hrtimer_interval_ms = timer; |
8765 | ||
8766 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8767 | get_online_cpus(); |
8768 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8769 | struct perf_cpu_context *cpuctx; |
8770 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8771 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8772 | ||
272325c4 PZ |
8773 | cpu_function_call(cpu, |
8774 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8775 | } |
272325c4 PZ |
8776 | put_online_cpus(); |
8777 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8778 | |
8779 | return count; | |
8780 | } | |
90826ca7 | 8781 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8782 | |
90826ca7 GKH |
8783 | static struct attribute *pmu_dev_attrs[] = { |
8784 | &dev_attr_type.attr, | |
8785 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8786 | NULL, | |
abe43400 | 8787 | }; |
90826ca7 | 8788 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8789 | |
8790 | static int pmu_bus_running; | |
8791 | static struct bus_type pmu_bus = { | |
8792 | .name = "event_source", | |
90826ca7 | 8793 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8794 | }; |
8795 | ||
8796 | static void pmu_dev_release(struct device *dev) | |
8797 | { | |
8798 | kfree(dev); | |
8799 | } | |
8800 | ||
8801 | static int pmu_dev_alloc(struct pmu *pmu) | |
8802 | { | |
8803 | int ret = -ENOMEM; | |
8804 | ||
8805 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8806 | if (!pmu->dev) | |
8807 | goto out; | |
8808 | ||
0c9d42ed | 8809 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8810 | device_initialize(pmu->dev); |
8811 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8812 | if (ret) | |
8813 | goto free_dev; | |
8814 | ||
8815 | dev_set_drvdata(pmu->dev, pmu); | |
8816 | pmu->dev->bus = &pmu_bus; | |
8817 | pmu->dev->release = pmu_dev_release; | |
8818 | ret = device_add(pmu->dev); | |
8819 | if (ret) | |
8820 | goto free_dev; | |
8821 | ||
6e855cd4 AS |
8822 | /* For PMUs with address filters, throw in an extra attribute: */ |
8823 | if (pmu->nr_addr_filters) | |
8824 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8825 | ||
8826 | if (ret) | |
8827 | goto del_dev; | |
8828 | ||
abe43400 PZ |
8829 | out: |
8830 | return ret; | |
8831 | ||
6e855cd4 AS |
8832 | del_dev: |
8833 | device_del(pmu->dev); | |
8834 | ||
abe43400 PZ |
8835 | free_dev: |
8836 | put_device(pmu->dev); | |
8837 | goto out; | |
8838 | } | |
8839 | ||
547e9fd7 | 8840 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8841 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8842 | |
03d8e80b | 8843 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 8844 | { |
108b02cf | 8845 | int cpu, ret; |
24f1e32c | 8846 | |
b0a873eb | 8847 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
8848 | ret = -ENOMEM; |
8849 | pmu->pmu_disable_count = alloc_percpu(int); | |
8850 | if (!pmu->pmu_disable_count) | |
8851 | goto unlock; | |
f29ac756 | 8852 | |
2e80a82a PZ |
8853 | pmu->type = -1; |
8854 | if (!name) | |
8855 | goto skip_type; | |
8856 | pmu->name = name; | |
8857 | ||
8858 | if (type < 0) { | |
0e9c3be2 TH |
8859 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
8860 | if (type < 0) { | |
8861 | ret = type; | |
2e80a82a PZ |
8862 | goto free_pdc; |
8863 | } | |
8864 | } | |
8865 | pmu->type = type; | |
8866 | ||
abe43400 PZ |
8867 | if (pmu_bus_running) { |
8868 | ret = pmu_dev_alloc(pmu); | |
8869 | if (ret) | |
8870 | goto free_idr; | |
8871 | } | |
8872 | ||
2e80a82a | 8873 | skip_type: |
26657848 PZ |
8874 | if (pmu->task_ctx_nr == perf_hw_context) { |
8875 | static int hw_context_taken = 0; | |
8876 | ||
5101ef20 MR |
8877 | /* |
8878 | * Other than systems with heterogeneous CPUs, it never makes | |
8879 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
8880 | * uncore must use perf_invalid_context. | |
8881 | */ | |
8882 | if (WARN_ON_ONCE(hw_context_taken && | |
8883 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
8884 | pmu->task_ctx_nr = perf_invalid_context; |
8885 | ||
8886 | hw_context_taken = 1; | |
8887 | } | |
8888 | ||
8dc85d54 PZ |
8889 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
8890 | if (pmu->pmu_cpu_context) | |
8891 | goto got_cpu_context; | |
f29ac756 | 8892 | |
c4814202 | 8893 | ret = -ENOMEM; |
108b02cf PZ |
8894 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
8895 | if (!pmu->pmu_cpu_context) | |
abe43400 | 8896 | goto free_dev; |
f344011c | 8897 | |
108b02cf PZ |
8898 | for_each_possible_cpu(cpu) { |
8899 | struct perf_cpu_context *cpuctx; | |
8900 | ||
8901 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 8902 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 8903 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 8904 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 8905 | cpuctx->ctx.pmu = pmu; |
9e630205 | 8906 | |
272325c4 | 8907 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 8908 | } |
76e1d904 | 8909 | |
8dc85d54 | 8910 | got_cpu_context: |
ad5133b7 PZ |
8911 | if (!pmu->start_txn) { |
8912 | if (pmu->pmu_enable) { | |
8913 | /* | |
8914 | * If we have pmu_enable/pmu_disable calls, install | |
8915 | * transaction stubs that use that to try and batch | |
8916 | * hardware accesses. | |
8917 | */ | |
8918 | pmu->start_txn = perf_pmu_start_txn; | |
8919 | pmu->commit_txn = perf_pmu_commit_txn; | |
8920 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
8921 | } else { | |
fbbe0701 | 8922 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
8923 | pmu->commit_txn = perf_pmu_nop_int; |
8924 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 8925 | } |
5c92d124 | 8926 | } |
15dbf27c | 8927 | |
ad5133b7 PZ |
8928 | if (!pmu->pmu_enable) { |
8929 | pmu->pmu_enable = perf_pmu_nop_void; | |
8930 | pmu->pmu_disable = perf_pmu_nop_void; | |
8931 | } | |
8932 | ||
35edc2a5 PZ |
8933 | if (!pmu->event_idx) |
8934 | pmu->event_idx = perf_event_idx_default; | |
8935 | ||
b0a873eb | 8936 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 8937 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
8938 | ret = 0; |
8939 | unlock: | |
b0a873eb PZ |
8940 | mutex_unlock(&pmus_lock); |
8941 | ||
33696fc0 | 8942 | return ret; |
108b02cf | 8943 | |
abe43400 PZ |
8944 | free_dev: |
8945 | device_del(pmu->dev); | |
8946 | put_device(pmu->dev); | |
8947 | ||
2e80a82a PZ |
8948 | free_idr: |
8949 | if (pmu->type >= PERF_TYPE_MAX) | |
8950 | idr_remove(&pmu_idr, pmu->type); | |
8951 | ||
108b02cf PZ |
8952 | free_pdc: |
8953 | free_percpu(pmu->pmu_disable_count); | |
8954 | goto unlock; | |
f29ac756 | 8955 | } |
c464c76e | 8956 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 8957 | |
b0a873eb | 8958 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 8959 | { |
0933840a JO |
8960 | int remove_device; |
8961 | ||
b0a873eb | 8962 | mutex_lock(&pmus_lock); |
0933840a | 8963 | remove_device = pmu_bus_running; |
b0a873eb PZ |
8964 | list_del_rcu(&pmu->entry); |
8965 | mutex_unlock(&pmus_lock); | |
5c92d124 | 8966 | |
0475f9ea | 8967 | /* |
cde8e884 PZ |
8968 | * We dereference the pmu list under both SRCU and regular RCU, so |
8969 | * synchronize against both of those. | |
0475f9ea | 8970 | */ |
b0a873eb | 8971 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 8972 | synchronize_rcu(); |
d6d020e9 | 8973 | |
33696fc0 | 8974 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
8975 | if (pmu->type >= PERF_TYPE_MAX) |
8976 | idr_remove(&pmu_idr, pmu->type); | |
0933840a JO |
8977 | if (remove_device) { |
8978 | if (pmu->nr_addr_filters) | |
8979 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8980 | device_del(pmu->dev); | |
8981 | put_device(pmu->dev); | |
8982 | } | |
51676957 | 8983 | free_pmu_context(pmu); |
b0a873eb | 8984 | } |
c464c76e | 8985 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 8986 | |
cc34b98b MR |
8987 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
8988 | { | |
ccd41c86 | 8989 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
8990 | int ret; |
8991 | ||
8992 | if (!try_module_get(pmu->module)) | |
8993 | return -ENODEV; | |
ccd41c86 PZ |
8994 | |
8995 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
8996 | /* |
8997 | * This ctx->mutex can nest when we're called through | |
8998 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
8999 | */ | |
9000 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
9001 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
9002 | BUG_ON(!ctx); |
9003 | } | |
9004 | ||
cc34b98b MR |
9005 | event->pmu = pmu; |
9006 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
9007 | |
9008 | if (ctx) | |
9009 | perf_event_ctx_unlock(event->group_leader, ctx); | |
9010 | ||
cc34b98b MR |
9011 | if (ret) |
9012 | module_put(pmu->module); | |
9013 | ||
9014 | return ret; | |
9015 | } | |
9016 | ||
18ab2cd3 | 9017 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
9018 | { |
9019 | struct pmu *pmu = NULL; | |
9020 | int idx; | |
940c5b29 | 9021 | int ret; |
b0a873eb PZ |
9022 | |
9023 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
9024 | |
9025 | rcu_read_lock(); | |
9026 | pmu = idr_find(&pmu_idr, event->attr.type); | |
9027 | rcu_read_unlock(); | |
940c5b29 | 9028 | if (pmu) { |
cc34b98b | 9029 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
9030 | if (ret) |
9031 | pmu = ERR_PTR(ret); | |
2e80a82a | 9032 | goto unlock; |
940c5b29 | 9033 | } |
2e80a82a | 9034 | |
b0a873eb | 9035 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 9036 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 9037 | if (!ret) |
e5f4d339 | 9038 | goto unlock; |
76e1d904 | 9039 | |
b0a873eb PZ |
9040 | if (ret != -ENOENT) { |
9041 | pmu = ERR_PTR(ret); | |
e5f4d339 | 9042 | goto unlock; |
f344011c | 9043 | } |
5c92d124 | 9044 | } |
e5f4d339 PZ |
9045 | pmu = ERR_PTR(-ENOENT); |
9046 | unlock: | |
b0a873eb | 9047 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 9048 | |
4aeb0b42 | 9049 | return pmu; |
5c92d124 IM |
9050 | } |
9051 | ||
f2fb6bef KL |
9052 | static void attach_sb_event(struct perf_event *event) |
9053 | { | |
9054 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
9055 | ||
9056 | raw_spin_lock(&pel->lock); | |
9057 | list_add_rcu(&event->sb_list, &pel->list); | |
9058 | raw_spin_unlock(&pel->lock); | |
9059 | } | |
9060 | ||
aab5b71e PZ |
9061 | /* |
9062 | * We keep a list of all !task (and therefore per-cpu) events | |
9063 | * that need to receive side-band records. | |
9064 | * | |
9065 | * This avoids having to scan all the various PMU per-cpu contexts | |
9066 | * looking for them. | |
9067 | */ | |
f2fb6bef KL |
9068 | static void account_pmu_sb_event(struct perf_event *event) |
9069 | { | |
a4f144eb | 9070 | if (is_sb_event(event)) |
f2fb6bef KL |
9071 | attach_sb_event(event); |
9072 | } | |
9073 | ||
4beb31f3 FW |
9074 | static void account_event_cpu(struct perf_event *event, int cpu) |
9075 | { | |
9076 | if (event->parent) | |
9077 | return; | |
9078 | ||
4beb31f3 FW |
9079 | if (is_cgroup_event(event)) |
9080 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9081 | } | |
9082 | ||
555e0c1e FW |
9083 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9084 | static void account_freq_event_nohz(void) | |
9085 | { | |
9086 | #ifdef CONFIG_NO_HZ_FULL | |
9087 | /* Lock so we don't race with concurrent unaccount */ | |
9088 | spin_lock(&nr_freq_lock); | |
9089 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9090 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9091 | spin_unlock(&nr_freq_lock); | |
9092 | #endif | |
9093 | } | |
9094 | ||
9095 | static void account_freq_event(void) | |
9096 | { | |
9097 | if (tick_nohz_full_enabled()) | |
9098 | account_freq_event_nohz(); | |
9099 | else | |
9100 | atomic_inc(&nr_freq_events); | |
9101 | } | |
9102 | ||
9103 | ||
766d6c07 FW |
9104 | static void account_event(struct perf_event *event) |
9105 | { | |
25432ae9 PZ |
9106 | bool inc = false; |
9107 | ||
4beb31f3 FW |
9108 | if (event->parent) |
9109 | return; | |
9110 | ||
766d6c07 | 9111 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9112 | inc = true; |
766d6c07 FW |
9113 | if (event->attr.mmap || event->attr.mmap_data) |
9114 | atomic_inc(&nr_mmap_events); | |
9115 | if (event->attr.comm) | |
9116 | atomic_inc(&nr_comm_events); | |
9117 | if (event->attr.task) | |
9118 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9119 | if (event->attr.freq) |
9120 | account_freq_event(); | |
45ac1403 AH |
9121 | if (event->attr.context_switch) { |
9122 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9123 | inc = true; |
45ac1403 | 9124 | } |
4beb31f3 | 9125 | if (has_branch_stack(event)) |
25432ae9 | 9126 | inc = true; |
4beb31f3 | 9127 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9128 | inc = true; |
9129 | ||
9107c89e PZ |
9130 | if (inc) { |
9131 | if (atomic_inc_not_zero(&perf_sched_count)) | |
9132 | goto enabled; | |
9133 | ||
9134 | mutex_lock(&perf_sched_mutex); | |
9135 | if (!atomic_read(&perf_sched_count)) { | |
9136 | static_branch_enable(&perf_sched_events); | |
9137 | /* | |
9138 | * Guarantee that all CPUs observe they key change and | |
9139 | * call the perf scheduling hooks before proceeding to | |
9140 | * install events that need them. | |
9141 | */ | |
9142 | synchronize_sched(); | |
9143 | } | |
9144 | /* | |
9145 | * Now that we have waited for the sync_sched(), allow further | |
9146 | * increments to by-pass the mutex. | |
9147 | */ | |
9148 | atomic_inc(&perf_sched_count); | |
9149 | mutex_unlock(&perf_sched_mutex); | |
9150 | } | |
9151 | enabled: | |
4beb31f3 FW |
9152 | |
9153 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9154 | |
9155 | account_pmu_sb_event(event); | |
766d6c07 FW |
9156 | } |
9157 | ||
0793a61d | 9158 | /* |
cdd6c482 | 9159 | * Allocate and initialize a event structure |
0793a61d | 9160 | */ |
cdd6c482 | 9161 | static struct perf_event * |
c3f00c70 | 9162 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9163 | struct task_struct *task, |
9164 | struct perf_event *group_leader, | |
9165 | struct perf_event *parent_event, | |
4dc0da86 | 9166 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9167 | void *context, int cgroup_fd) |
0793a61d | 9168 | { |
51b0fe39 | 9169 | struct pmu *pmu; |
cdd6c482 IM |
9170 | struct perf_event *event; |
9171 | struct hw_perf_event *hwc; | |
90983b16 | 9172 | long err = -EINVAL; |
0793a61d | 9173 | |
66832eb4 ON |
9174 | if ((unsigned)cpu >= nr_cpu_ids) { |
9175 | if (!task || cpu != -1) | |
9176 | return ERR_PTR(-EINVAL); | |
9177 | } | |
9178 | ||
c3f00c70 | 9179 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9180 | if (!event) |
d5d2bc0d | 9181 | return ERR_PTR(-ENOMEM); |
0793a61d | 9182 | |
04289bb9 | 9183 | /* |
cdd6c482 | 9184 | * Single events are their own group leaders, with an |
04289bb9 IM |
9185 | * empty sibling list: |
9186 | */ | |
9187 | if (!group_leader) | |
cdd6c482 | 9188 | group_leader = event; |
04289bb9 | 9189 | |
cdd6c482 IM |
9190 | mutex_init(&event->child_mutex); |
9191 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9192 | |
cdd6c482 IM |
9193 | INIT_LIST_HEAD(&event->group_entry); |
9194 | INIT_LIST_HEAD(&event->event_entry); | |
9195 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 9196 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9197 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9198 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9199 | INIT_HLIST_NODE(&event->hlist_entry); |
9200 | ||
10c6db11 | 9201 | |
cdd6c482 | 9202 | init_waitqueue_head(&event->waitq); |
e360adbe | 9203 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9204 | |
cdd6c482 | 9205 | mutex_init(&event->mmap_mutex); |
375637bc | 9206 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9207 | |
a6fa941d | 9208 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9209 | event->cpu = cpu; |
9210 | event->attr = *attr; | |
9211 | event->group_leader = group_leader; | |
9212 | event->pmu = NULL; | |
cdd6c482 | 9213 | event->oncpu = -1; |
a96bbc16 | 9214 | |
cdd6c482 | 9215 | event->parent = parent_event; |
b84fbc9f | 9216 | |
17cf22c3 | 9217 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9218 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9219 | |
cdd6c482 | 9220 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9221 | |
d580ff86 PZ |
9222 | if (task) { |
9223 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9224 | /* |
50f16a8b PZ |
9225 | * XXX pmu::event_init needs to know what task to account to |
9226 | * and we cannot use the ctx information because we need the | |
9227 | * pmu before we get a ctx. | |
d580ff86 | 9228 | */ |
50f16a8b | 9229 | event->hw.target = task; |
d580ff86 PZ |
9230 | } |
9231 | ||
34f43927 PZ |
9232 | event->clock = &local_clock; |
9233 | if (parent_event) | |
9234 | event->clock = parent_event->clock; | |
9235 | ||
4dc0da86 | 9236 | if (!overflow_handler && parent_event) { |
b326e956 | 9237 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9238 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9239 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9240 | if (overflow_handler == bpf_overflow_handler) { |
9241 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9242 | ||
9243 | if (IS_ERR(prog)) { | |
9244 | err = PTR_ERR(prog); | |
9245 | goto err_ns; | |
9246 | } | |
9247 | event->prog = prog; | |
9248 | event->orig_overflow_handler = | |
9249 | parent_event->orig_overflow_handler; | |
9250 | } | |
9251 | #endif | |
4dc0da86 | 9252 | } |
66832eb4 | 9253 | |
1879445d WN |
9254 | if (overflow_handler) { |
9255 | event->overflow_handler = overflow_handler; | |
9256 | event->overflow_handler_context = context; | |
9ecda41a WN |
9257 | } else if (is_write_backward(event)){ |
9258 | event->overflow_handler = perf_event_output_backward; | |
9259 | event->overflow_handler_context = NULL; | |
1879445d | 9260 | } else { |
9ecda41a | 9261 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9262 | event->overflow_handler_context = NULL; |
9263 | } | |
97eaf530 | 9264 | |
0231bb53 | 9265 | perf_event__state_init(event); |
a86ed508 | 9266 | |
4aeb0b42 | 9267 | pmu = NULL; |
b8e83514 | 9268 | |
cdd6c482 | 9269 | hwc = &event->hw; |
bd2b5b12 | 9270 | hwc->sample_period = attr->sample_period; |
0d48696f | 9271 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9272 | hwc->sample_period = 1; |
eced1dfc | 9273 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9274 | |
e7850595 | 9275 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9276 | |
2023b359 | 9277 | /* |
cdd6c482 | 9278 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 9279 | */ |
3dab77fb | 9280 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 9281 | goto err_ns; |
a46a2300 YZ |
9282 | |
9283 | if (!has_branch_stack(event)) | |
9284 | event->attr.branch_sample_type = 0; | |
2023b359 | 9285 | |
79dff51e MF |
9286 | if (cgroup_fd != -1) { |
9287 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9288 | if (err) | |
9289 | goto err_ns; | |
9290 | } | |
9291 | ||
b0a873eb | 9292 | pmu = perf_init_event(event); |
4aeb0b42 | 9293 | if (!pmu) |
90983b16 FW |
9294 | goto err_ns; |
9295 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 9296 | err = PTR_ERR(pmu); |
90983b16 | 9297 | goto err_ns; |
621a01ea | 9298 | } |
d5d2bc0d | 9299 | |
bed5b25a AS |
9300 | err = exclusive_event_init(event); |
9301 | if (err) | |
9302 | goto err_pmu; | |
9303 | ||
375637bc AS |
9304 | if (has_addr_filter(event)) { |
9305 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9306 | sizeof(unsigned long), | |
9307 | GFP_KERNEL); | |
9308 | if (!event->addr_filters_offs) | |
9309 | goto err_per_task; | |
9310 | ||
9311 | /* force hw sync on the address filters */ | |
9312 | event->addr_filters_gen = 1; | |
9313 | } | |
9314 | ||
cdd6c482 | 9315 | if (!event->parent) { |
927c7a9e | 9316 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9317 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9318 | if (err) |
375637bc | 9319 | goto err_addr_filters; |
d010b332 | 9320 | } |
f344011c | 9321 | } |
9ee318a7 | 9322 | |
927a5570 AS |
9323 | /* symmetric to unaccount_event() in _free_event() */ |
9324 | account_event(event); | |
9325 | ||
cdd6c482 | 9326 | return event; |
90983b16 | 9327 | |
375637bc AS |
9328 | err_addr_filters: |
9329 | kfree(event->addr_filters_offs); | |
9330 | ||
bed5b25a AS |
9331 | err_per_task: |
9332 | exclusive_event_destroy(event); | |
9333 | ||
90983b16 FW |
9334 | err_pmu: |
9335 | if (event->destroy) | |
9336 | event->destroy(event); | |
c464c76e | 9337 | module_put(pmu->module); |
90983b16 | 9338 | err_ns: |
79dff51e MF |
9339 | if (is_cgroup_event(event)) |
9340 | perf_detach_cgroup(event); | |
90983b16 FW |
9341 | if (event->ns) |
9342 | put_pid_ns(event->ns); | |
9343 | kfree(event); | |
9344 | ||
9345 | return ERR_PTR(err); | |
0793a61d TG |
9346 | } |
9347 | ||
cdd6c482 IM |
9348 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9349 | struct perf_event_attr *attr) | |
974802ea | 9350 | { |
974802ea | 9351 | u32 size; |
cdf8073d | 9352 | int ret; |
974802ea PZ |
9353 | |
9354 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9355 | return -EFAULT; | |
9356 | ||
9357 | /* | |
9358 | * zero the full structure, so that a short copy will be nice. | |
9359 | */ | |
9360 | memset(attr, 0, sizeof(*attr)); | |
9361 | ||
9362 | ret = get_user(size, &uattr->size); | |
9363 | if (ret) | |
9364 | return ret; | |
9365 | ||
9366 | if (size > PAGE_SIZE) /* silly large */ | |
9367 | goto err_size; | |
9368 | ||
9369 | if (!size) /* abi compat */ | |
9370 | size = PERF_ATTR_SIZE_VER0; | |
9371 | ||
9372 | if (size < PERF_ATTR_SIZE_VER0) | |
9373 | goto err_size; | |
9374 | ||
9375 | /* | |
9376 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9377 | * ensure all the unknown bits are 0 - i.e. new |
9378 | * user-space does not rely on any kernel feature | |
9379 | * extensions we dont know about yet. | |
974802ea PZ |
9380 | */ |
9381 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9382 | unsigned char __user *addr; |
9383 | unsigned char __user *end; | |
9384 | unsigned char val; | |
974802ea | 9385 | |
cdf8073d IS |
9386 | addr = (void __user *)uattr + sizeof(*attr); |
9387 | end = (void __user *)uattr + size; | |
974802ea | 9388 | |
cdf8073d | 9389 | for (; addr < end; addr++) { |
974802ea PZ |
9390 | ret = get_user(val, addr); |
9391 | if (ret) | |
9392 | return ret; | |
9393 | if (val) | |
9394 | goto err_size; | |
9395 | } | |
b3e62e35 | 9396 | size = sizeof(*attr); |
974802ea PZ |
9397 | } |
9398 | ||
9399 | ret = copy_from_user(attr, uattr, size); | |
9400 | if (ret) | |
9401 | return -EFAULT; | |
9402 | ||
cd757645 | 9403 | if (attr->__reserved_1) |
974802ea PZ |
9404 | return -EINVAL; |
9405 | ||
9406 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9407 | return -EINVAL; | |
9408 | ||
9409 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9410 | return -EINVAL; | |
9411 | ||
bce38cd5 SE |
9412 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9413 | u64 mask = attr->branch_sample_type; | |
9414 | ||
9415 | /* only using defined bits */ | |
9416 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9417 | return -EINVAL; | |
9418 | ||
9419 | /* at least one branch bit must be set */ | |
9420 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9421 | return -EINVAL; | |
9422 | ||
bce38cd5 SE |
9423 | /* propagate priv level, when not set for branch */ |
9424 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9425 | ||
9426 | /* exclude_kernel checked on syscall entry */ | |
9427 | if (!attr->exclude_kernel) | |
9428 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9429 | ||
9430 | if (!attr->exclude_user) | |
9431 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9432 | ||
9433 | if (!attr->exclude_hv) | |
9434 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9435 | /* | |
9436 | * adjust user setting (for HW filter setup) | |
9437 | */ | |
9438 | attr->branch_sample_type = mask; | |
9439 | } | |
e712209a SE |
9440 | /* privileged levels capture (kernel, hv): check permissions */ |
9441 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9442 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9443 | return -EACCES; | |
bce38cd5 | 9444 | } |
4018994f | 9445 | |
c5ebcedb | 9446 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9447 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9448 | if (ret) |
9449 | return ret; | |
9450 | } | |
9451 | ||
9452 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9453 | if (!arch_perf_have_user_stack_dump()) | |
9454 | return -ENOSYS; | |
9455 | ||
9456 | /* | |
9457 | * We have __u32 type for the size, but so far | |
9458 | * we can only use __u16 as maximum due to the | |
9459 | * __u16 sample size limit. | |
9460 | */ | |
9461 | if (attr->sample_stack_user >= USHRT_MAX) | |
9462 | ret = -EINVAL; | |
9463 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9464 | ret = -EINVAL; | |
9465 | } | |
4018994f | 9466 | |
60e2364e SE |
9467 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9468 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9469 | out: |
9470 | return ret; | |
9471 | ||
9472 | err_size: | |
9473 | put_user(sizeof(*attr), &uattr->size); | |
9474 | ret = -E2BIG; | |
9475 | goto out; | |
9476 | } | |
9477 | ||
ac9721f3 PZ |
9478 | static int |
9479 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9480 | { |
b69cf536 | 9481 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9482 | int ret = -EINVAL; |
9483 | ||
ac9721f3 | 9484 | if (!output_event) |
a4be7c27 PZ |
9485 | goto set; |
9486 | ||
ac9721f3 PZ |
9487 | /* don't allow circular references */ |
9488 | if (event == output_event) | |
a4be7c27 PZ |
9489 | goto out; |
9490 | ||
0f139300 PZ |
9491 | /* |
9492 | * Don't allow cross-cpu buffers | |
9493 | */ | |
9494 | if (output_event->cpu != event->cpu) | |
9495 | goto out; | |
9496 | ||
9497 | /* | |
76369139 | 9498 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9499 | */ |
9500 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9501 | goto out; | |
9502 | ||
34f43927 PZ |
9503 | /* |
9504 | * Mixing clocks in the same buffer is trouble you don't need. | |
9505 | */ | |
9506 | if (output_event->clock != event->clock) | |
9507 | goto out; | |
9508 | ||
9ecda41a WN |
9509 | /* |
9510 | * Either writing ring buffer from beginning or from end. | |
9511 | * Mixing is not allowed. | |
9512 | */ | |
9513 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9514 | goto out; | |
9515 | ||
45bfb2e5 PZ |
9516 | /* |
9517 | * If both events generate aux data, they must be on the same PMU | |
9518 | */ | |
9519 | if (has_aux(event) && has_aux(output_event) && | |
9520 | event->pmu != output_event->pmu) | |
9521 | goto out; | |
9522 | ||
a4be7c27 | 9523 | set: |
cdd6c482 | 9524 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9525 | /* Can't redirect output if we've got an active mmap() */ |
9526 | if (atomic_read(&event->mmap_count)) | |
9527 | goto unlock; | |
a4be7c27 | 9528 | |
ac9721f3 | 9529 | if (output_event) { |
76369139 FW |
9530 | /* get the rb we want to redirect to */ |
9531 | rb = ring_buffer_get(output_event); | |
9532 | if (!rb) | |
ac9721f3 | 9533 | goto unlock; |
a4be7c27 PZ |
9534 | } |
9535 | ||
b69cf536 | 9536 | ring_buffer_attach(event, rb); |
9bb5d40c | 9537 | |
a4be7c27 | 9538 | ret = 0; |
ac9721f3 PZ |
9539 | unlock: |
9540 | mutex_unlock(&event->mmap_mutex); | |
9541 | ||
a4be7c27 | 9542 | out: |
a4be7c27 PZ |
9543 | return ret; |
9544 | } | |
9545 | ||
f63a8daa PZ |
9546 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9547 | { | |
9548 | if (b < a) | |
9549 | swap(a, b); | |
9550 | ||
9551 | mutex_lock(a); | |
9552 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9553 | } | |
9554 | ||
34f43927 PZ |
9555 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9556 | { | |
9557 | bool nmi_safe = false; | |
9558 | ||
9559 | switch (clk_id) { | |
9560 | case CLOCK_MONOTONIC: | |
9561 | event->clock = &ktime_get_mono_fast_ns; | |
9562 | nmi_safe = true; | |
9563 | break; | |
9564 | ||
9565 | case CLOCK_MONOTONIC_RAW: | |
9566 | event->clock = &ktime_get_raw_fast_ns; | |
9567 | nmi_safe = true; | |
9568 | break; | |
9569 | ||
9570 | case CLOCK_REALTIME: | |
9571 | event->clock = &ktime_get_real_ns; | |
9572 | break; | |
9573 | ||
9574 | case CLOCK_BOOTTIME: | |
9575 | event->clock = &ktime_get_boot_ns; | |
9576 | break; | |
9577 | ||
9578 | case CLOCK_TAI: | |
9579 | event->clock = &ktime_get_tai_ns; | |
9580 | break; | |
9581 | ||
9582 | default: | |
9583 | return -EINVAL; | |
9584 | } | |
9585 | ||
9586 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9587 | return -EINVAL; | |
9588 | ||
9589 | return 0; | |
9590 | } | |
9591 | ||
321027c1 PZ |
9592 | /* |
9593 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
9594 | * mutexes. | |
9595 | */ | |
9596 | static struct perf_event_context * | |
9597 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
9598 | struct perf_event_context *ctx) | |
9599 | { | |
9600 | struct perf_event_context *gctx; | |
9601 | ||
9602 | again: | |
9603 | rcu_read_lock(); | |
9604 | gctx = READ_ONCE(group_leader->ctx); | |
9605 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
9606 | rcu_read_unlock(); | |
9607 | goto again; | |
9608 | } | |
9609 | rcu_read_unlock(); | |
9610 | ||
9611 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
9612 | ||
9613 | if (group_leader->ctx != gctx) { | |
9614 | mutex_unlock(&ctx->mutex); | |
9615 | mutex_unlock(&gctx->mutex); | |
9616 | put_ctx(gctx); | |
9617 | goto again; | |
9618 | } | |
9619 | ||
9620 | return gctx; | |
9621 | } | |
9622 | ||
0793a61d | 9623 | /** |
cdd6c482 | 9624 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9625 | * |
cdd6c482 | 9626 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9627 | * @pid: target pid |
9f66a381 | 9628 | * @cpu: target cpu |
cdd6c482 | 9629 | * @group_fd: group leader event fd |
0793a61d | 9630 | */ |
cdd6c482 IM |
9631 | SYSCALL_DEFINE5(perf_event_open, |
9632 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9633 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9634 | { |
b04243ef PZ |
9635 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9636 | struct perf_event *event, *sibling; | |
cdd6c482 | 9637 | struct perf_event_attr attr; |
f63a8daa | 9638 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9639 | struct file *event_file = NULL; |
2903ff01 | 9640 | struct fd group = {NULL, 0}; |
38a81da2 | 9641 | struct task_struct *task = NULL; |
89a1e187 | 9642 | struct pmu *pmu; |
ea635c64 | 9643 | int event_fd; |
b04243ef | 9644 | int move_group = 0; |
dc86cabe | 9645 | int err; |
a21b0b35 | 9646 | int f_flags = O_RDWR; |
79dff51e | 9647 | int cgroup_fd = -1; |
0793a61d | 9648 | |
2743a5b0 | 9649 | /* for future expandability... */ |
e5d1367f | 9650 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9651 | return -EINVAL; |
9652 | ||
dc86cabe IM |
9653 | err = perf_copy_attr(attr_uptr, &attr); |
9654 | if (err) | |
9655 | return err; | |
eab656ae | 9656 | |
0764771d PZ |
9657 | if (!attr.exclude_kernel) { |
9658 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9659 | return -EACCES; | |
9660 | } | |
9661 | ||
df58ab24 | 9662 | if (attr.freq) { |
cdd6c482 | 9663 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9664 | return -EINVAL; |
0819b2e3 PZ |
9665 | } else { |
9666 | if (attr.sample_period & (1ULL << 63)) | |
9667 | return -EINVAL; | |
df58ab24 PZ |
9668 | } |
9669 | ||
97c79a38 ACM |
9670 | if (!attr.sample_max_stack) |
9671 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9672 | ||
e5d1367f SE |
9673 | /* |
9674 | * In cgroup mode, the pid argument is used to pass the fd | |
9675 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9676 | * designates the cpu on which to monitor threads from that | |
9677 | * cgroup. | |
9678 | */ | |
9679 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9680 | return -EINVAL; | |
9681 | ||
a21b0b35 YD |
9682 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9683 | f_flags |= O_CLOEXEC; | |
9684 | ||
9685 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9686 | if (event_fd < 0) |
9687 | return event_fd; | |
9688 | ||
ac9721f3 | 9689 | if (group_fd != -1) { |
2903ff01 AV |
9690 | err = perf_fget_light(group_fd, &group); |
9691 | if (err) | |
d14b12d7 | 9692 | goto err_fd; |
2903ff01 | 9693 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9694 | if (flags & PERF_FLAG_FD_OUTPUT) |
9695 | output_event = group_leader; | |
9696 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9697 | group_leader = NULL; | |
9698 | } | |
9699 | ||
e5d1367f | 9700 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9701 | task = find_lively_task_by_vpid(pid); |
9702 | if (IS_ERR(task)) { | |
9703 | err = PTR_ERR(task); | |
9704 | goto err_group_fd; | |
9705 | } | |
9706 | } | |
9707 | ||
1f4ee503 PZ |
9708 | if (task && group_leader && |
9709 | group_leader->attr.inherit != attr.inherit) { | |
9710 | err = -EINVAL; | |
9711 | goto err_task; | |
9712 | } | |
9713 | ||
fbfc623f YZ |
9714 | get_online_cpus(); |
9715 | ||
79c9ce57 PZ |
9716 | if (task) { |
9717 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9718 | if (err) | |
9719 | goto err_cpus; | |
9720 | ||
9721 | /* | |
9722 | * Reuse ptrace permission checks for now. | |
9723 | * | |
9724 | * We must hold cred_guard_mutex across this and any potential | |
9725 | * perf_install_in_context() call for this new event to | |
9726 | * serialize against exec() altering our credentials (and the | |
9727 | * perf_event_exit_task() that could imply). | |
9728 | */ | |
9729 | err = -EACCES; | |
9730 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9731 | goto err_cred; | |
9732 | } | |
9733 | ||
79dff51e MF |
9734 | if (flags & PERF_FLAG_PID_CGROUP) |
9735 | cgroup_fd = pid; | |
9736 | ||
4dc0da86 | 9737 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9738 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9739 | if (IS_ERR(event)) { |
9740 | err = PTR_ERR(event); | |
79c9ce57 | 9741 | goto err_cred; |
d14b12d7 SE |
9742 | } |
9743 | ||
53b25335 VW |
9744 | if (is_sampling_event(event)) { |
9745 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9746 | err = -EOPNOTSUPP; |
53b25335 VW |
9747 | goto err_alloc; |
9748 | } | |
9749 | } | |
9750 | ||
89a1e187 PZ |
9751 | /* |
9752 | * Special case software events and allow them to be part of | |
9753 | * any hardware group. | |
9754 | */ | |
9755 | pmu = event->pmu; | |
b04243ef | 9756 | |
34f43927 PZ |
9757 | if (attr.use_clockid) { |
9758 | err = perf_event_set_clock(event, attr.clockid); | |
9759 | if (err) | |
9760 | goto err_alloc; | |
9761 | } | |
9762 | ||
4ff6a8de DCC |
9763 | if (pmu->task_ctx_nr == perf_sw_context) |
9764 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
9765 | ||
b04243ef PZ |
9766 | if (group_leader && |
9767 | (is_software_event(event) != is_software_event(group_leader))) { | |
9768 | if (is_software_event(event)) { | |
9769 | /* | |
9770 | * If event and group_leader are not both a software | |
9771 | * event, and event is, then group leader is not. | |
9772 | * | |
9773 | * Allow the addition of software events to !software | |
9774 | * groups, this is safe because software events never | |
9775 | * fail to schedule. | |
9776 | */ | |
9777 | pmu = group_leader->pmu; | |
9778 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 9779 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
9780 | /* |
9781 | * In case the group is a pure software group, and we | |
9782 | * try to add a hardware event, move the whole group to | |
9783 | * the hardware context. | |
9784 | */ | |
9785 | move_group = 1; | |
9786 | } | |
9787 | } | |
89a1e187 PZ |
9788 | |
9789 | /* | |
9790 | * Get the target context (task or percpu): | |
9791 | */ | |
4af57ef2 | 9792 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9793 | if (IS_ERR(ctx)) { |
9794 | err = PTR_ERR(ctx); | |
c6be5a5c | 9795 | goto err_alloc; |
89a1e187 PZ |
9796 | } |
9797 | ||
bed5b25a AS |
9798 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9799 | err = -EBUSY; | |
9800 | goto err_context; | |
9801 | } | |
9802 | ||
ccff286d | 9803 | /* |
cdd6c482 | 9804 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9805 | */ |
ac9721f3 | 9806 | if (group_leader) { |
dc86cabe | 9807 | err = -EINVAL; |
04289bb9 | 9808 | |
04289bb9 | 9809 | /* |
ccff286d IM |
9810 | * Do not allow a recursive hierarchy (this new sibling |
9811 | * becoming part of another group-sibling): | |
9812 | */ | |
9813 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9814 | goto err_context; |
34f43927 PZ |
9815 | |
9816 | /* All events in a group should have the same clock */ | |
9817 | if (group_leader->clock != event->clock) | |
9818 | goto err_context; | |
9819 | ||
ccff286d IM |
9820 | /* |
9821 | * Do not allow to attach to a group in a different | |
9822 | * task or CPU context: | |
04289bb9 | 9823 | */ |
b04243ef | 9824 | if (move_group) { |
c3c87e77 PZ |
9825 | /* |
9826 | * Make sure we're both on the same task, or both | |
9827 | * per-cpu events. | |
9828 | */ | |
9829 | if (group_leader->ctx->task != ctx->task) | |
9830 | goto err_context; | |
9831 | ||
9832 | /* | |
9833 | * Make sure we're both events for the same CPU; | |
9834 | * grouping events for different CPUs is broken; since | |
9835 | * you can never concurrently schedule them anyhow. | |
9836 | */ | |
9837 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
9838 | goto err_context; |
9839 | } else { | |
9840 | if (group_leader->ctx != ctx) | |
9841 | goto err_context; | |
9842 | } | |
9843 | ||
3b6f9e5c PM |
9844 | /* |
9845 | * Only a group leader can be exclusive or pinned | |
9846 | */ | |
0d48696f | 9847 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 9848 | goto err_context; |
ac9721f3 PZ |
9849 | } |
9850 | ||
9851 | if (output_event) { | |
9852 | err = perf_event_set_output(event, output_event); | |
9853 | if (err) | |
c3f00c70 | 9854 | goto err_context; |
ac9721f3 | 9855 | } |
0793a61d | 9856 | |
a21b0b35 YD |
9857 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
9858 | f_flags); | |
ea635c64 AV |
9859 | if (IS_ERR(event_file)) { |
9860 | err = PTR_ERR(event_file); | |
201c2f85 | 9861 | event_file = NULL; |
c3f00c70 | 9862 | goto err_context; |
ea635c64 | 9863 | } |
9b51f66d | 9864 | |
b04243ef | 9865 | if (move_group) { |
321027c1 PZ |
9866 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
9867 | ||
84c4e620 PZ |
9868 | if (gctx->task == TASK_TOMBSTONE) { |
9869 | err = -ESRCH; | |
9870 | goto err_locked; | |
9871 | } | |
321027c1 PZ |
9872 | |
9873 | /* | |
9874 | * Check if we raced against another sys_perf_event_open() call | |
9875 | * moving the software group underneath us. | |
9876 | */ | |
9877 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
9878 | /* | |
9879 | * If someone moved the group out from under us, check | |
9880 | * if this new event wound up on the same ctx, if so | |
9881 | * its the regular !move_group case, otherwise fail. | |
9882 | */ | |
9883 | if (gctx != ctx) { | |
9884 | err = -EINVAL; | |
9885 | goto err_locked; | |
9886 | } else { | |
9887 | perf_event_ctx_unlock(group_leader, gctx); | |
9888 | move_group = 0; | |
9889 | } | |
9890 | } | |
f55fc2a5 PZ |
9891 | } else { |
9892 | mutex_lock(&ctx->mutex); | |
9893 | } | |
9894 | ||
84c4e620 PZ |
9895 | if (ctx->task == TASK_TOMBSTONE) { |
9896 | err = -ESRCH; | |
9897 | goto err_locked; | |
9898 | } | |
9899 | ||
a723968c PZ |
9900 | if (!perf_event_validate_size(event)) { |
9901 | err = -E2BIG; | |
9902 | goto err_locked; | |
9903 | } | |
9904 | ||
f55fc2a5 PZ |
9905 | /* |
9906 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
9907 | * because we need to serialize with concurrent event creation. | |
9908 | */ | |
9909 | if (!exclusive_event_installable(event, ctx)) { | |
9910 | /* exclusive and group stuff are assumed mutually exclusive */ | |
9911 | WARN_ON_ONCE(move_group); | |
f63a8daa | 9912 | |
f55fc2a5 PZ |
9913 | err = -EBUSY; |
9914 | goto err_locked; | |
9915 | } | |
f63a8daa | 9916 | |
f55fc2a5 PZ |
9917 | WARN_ON_ONCE(ctx->parent_ctx); |
9918 | ||
79c9ce57 PZ |
9919 | /* |
9920 | * This is the point on no return; we cannot fail hereafter. This is | |
9921 | * where we start modifying current state. | |
9922 | */ | |
9923 | ||
f55fc2a5 | 9924 | if (move_group) { |
f63a8daa PZ |
9925 | /* |
9926 | * See perf_event_ctx_lock() for comments on the details | |
9927 | * of swizzling perf_event::ctx. | |
9928 | */ | |
45a0e07a | 9929 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 9930 | |
b04243ef PZ |
9931 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9932 | group_entry) { | |
45a0e07a | 9933 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
9934 | put_ctx(gctx); |
9935 | } | |
b04243ef | 9936 | |
f63a8daa PZ |
9937 | /* |
9938 | * Wait for everybody to stop referencing the events through | |
9939 | * the old lists, before installing it on new lists. | |
9940 | */ | |
0cda4c02 | 9941 | synchronize_rcu(); |
f63a8daa | 9942 | |
8f95b435 PZI |
9943 | /* |
9944 | * Install the group siblings before the group leader. | |
9945 | * | |
9946 | * Because a group leader will try and install the entire group | |
9947 | * (through the sibling list, which is still in-tact), we can | |
9948 | * end up with siblings installed in the wrong context. | |
9949 | * | |
9950 | * By installing siblings first we NO-OP because they're not | |
9951 | * reachable through the group lists. | |
9952 | */ | |
b04243ef PZ |
9953 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9954 | group_entry) { | |
8f95b435 | 9955 | perf_event__state_init(sibling); |
9fc81d87 | 9956 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
9957 | get_ctx(ctx); |
9958 | } | |
8f95b435 PZI |
9959 | |
9960 | /* | |
9961 | * Removing from the context ends up with disabled | |
9962 | * event. What we want here is event in the initial | |
9963 | * startup state, ready to be add into new context. | |
9964 | */ | |
9965 | perf_event__state_init(group_leader); | |
9966 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
9967 | get_ctx(ctx); | |
b04243ef | 9968 | |
f55fc2a5 PZ |
9969 | /* |
9970 | * Now that all events are installed in @ctx, nothing | |
9971 | * references @gctx anymore, so drop the last reference we have | |
9972 | * on it. | |
9973 | */ | |
9974 | put_ctx(gctx); | |
bed5b25a AS |
9975 | } |
9976 | ||
f73e22ab PZ |
9977 | /* |
9978 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
9979 | * that we're serialized against further additions and before | |
9980 | * perf_install_in_context() which is the point the event is active and | |
9981 | * can use these values. | |
9982 | */ | |
9983 | perf_event__header_size(event); | |
9984 | perf_event__id_header_size(event); | |
9985 | ||
78cd2c74 PZ |
9986 | event->owner = current; |
9987 | ||
e2d37cd2 | 9988 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 9989 | perf_unpin_context(ctx); |
f63a8daa | 9990 | |
f55fc2a5 | 9991 | if (move_group) |
321027c1 | 9992 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 9993 | mutex_unlock(&ctx->mutex); |
9b51f66d | 9994 | |
79c9ce57 PZ |
9995 | if (task) { |
9996 | mutex_unlock(&task->signal->cred_guard_mutex); | |
9997 | put_task_struct(task); | |
9998 | } | |
9999 | ||
fbfc623f YZ |
10000 | put_online_cpus(); |
10001 | ||
cdd6c482 IM |
10002 | mutex_lock(¤t->perf_event_mutex); |
10003 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
10004 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 10005 | |
8a49542c PZ |
10006 | /* |
10007 | * Drop the reference on the group_event after placing the | |
10008 | * new event on the sibling_list. This ensures destruction | |
10009 | * of the group leader will find the pointer to itself in | |
10010 | * perf_group_detach(). | |
10011 | */ | |
2903ff01 | 10012 | fdput(group); |
ea635c64 AV |
10013 | fd_install(event_fd, event_file); |
10014 | return event_fd; | |
0793a61d | 10015 | |
f55fc2a5 PZ |
10016 | err_locked: |
10017 | if (move_group) | |
321027c1 | 10018 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
10019 | mutex_unlock(&ctx->mutex); |
10020 | /* err_file: */ | |
10021 | fput(event_file); | |
c3f00c70 | 10022 | err_context: |
fe4b04fa | 10023 | perf_unpin_context(ctx); |
ea635c64 | 10024 | put_ctx(ctx); |
c6be5a5c | 10025 | err_alloc: |
13005627 PZ |
10026 | /* |
10027 | * If event_file is set, the fput() above will have called ->release() | |
10028 | * and that will take care of freeing the event. | |
10029 | */ | |
10030 | if (!event_file) | |
10031 | free_event(event); | |
79c9ce57 PZ |
10032 | err_cred: |
10033 | if (task) | |
10034 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 10035 | err_cpus: |
fbfc623f | 10036 | put_online_cpus(); |
1f4ee503 | 10037 | err_task: |
e7d0bc04 PZ |
10038 | if (task) |
10039 | put_task_struct(task); | |
89a1e187 | 10040 | err_group_fd: |
2903ff01 | 10041 | fdput(group); |
ea635c64 AV |
10042 | err_fd: |
10043 | put_unused_fd(event_fd); | |
dc86cabe | 10044 | return err; |
0793a61d TG |
10045 | } |
10046 | ||
fb0459d7 AV |
10047 | /** |
10048 | * perf_event_create_kernel_counter | |
10049 | * | |
10050 | * @attr: attributes of the counter to create | |
10051 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 10052 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
10053 | */ |
10054 | struct perf_event * | |
10055 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 10056 | struct task_struct *task, |
4dc0da86 AK |
10057 | perf_overflow_handler_t overflow_handler, |
10058 | void *context) | |
fb0459d7 | 10059 | { |
fb0459d7 | 10060 | struct perf_event_context *ctx; |
c3f00c70 | 10061 | struct perf_event *event; |
fb0459d7 | 10062 | int err; |
d859e29f | 10063 | |
fb0459d7 AV |
10064 | /* |
10065 | * Get the target context (task or percpu): | |
10066 | */ | |
d859e29f | 10067 | |
4dc0da86 | 10068 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10069 | overflow_handler, context, -1); |
c3f00c70 PZ |
10070 | if (IS_ERR(event)) { |
10071 | err = PTR_ERR(event); | |
10072 | goto err; | |
10073 | } | |
d859e29f | 10074 | |
f8697762 | 10075 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10076 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10077 | |
4af57ef2 | 10078 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10079 | if (IS_ERR(ctx)) { |
10080 | err = PTR_ERR(ctx); | |
c3f00c70 | 10081 | goto err_free; |
d859e29f | 10082 | } |
fb0459d7 | 10083 | |
fb0459d7 AV |
10084 | WARN_ON_ONCE(ctx->parent_ctx); |
10085 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10086 | if (ctx->task == TASK_TOMBSTONE) { |
10087 | err = -ESRCH; | |
10088 | goto err_unlock; | |
10089 | } | |
10090 | ||
bed5b25a | 10091 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10092 | err = -EBUSY; |
84c4e620 | 10093 | goto err_unlock; |
bed5b25a AS |
10094 | } |
10095 | ||
fb0459d7 | 10096 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 10097 | perf_unpin_context(ctx); |
fb0459d7 AV |
10098 | mutex_unlock(&ctx->mutex); |
10099 | ||
fb0459d7 AV |
10100 | return event; |
10101 | ||
84c4e620 PZ |
10102 | err_unlock: |
10103 | mutex_unlock(&ctx->mutex); | |
10104 | perf_unpin_context(ctx); | |
10105 | put_ctx(ctx); | |
c3f00c70 PZ |
10106 | err_free: |
10107 | free_event(event); | |
10108 | err: | |
c6567f64 | 10109 | return ERR_PTR(err); |
9b51f66d | 10110 | } |
fb0459d7 | 10111 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10112 | |
0cda4c02 YZ |
10113 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10114 | { | |
10115 | struct perf_event_context *src_ctx; | |
10116 | struct perf_event_context *dst_ctx; | |
10117 | struct perf_event *event, *tmp; | |
10118 | LIST_HEAD(events); | |
10119 | ||
10120 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10121 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10122 | ||
f63a8daa PZ |
10123 | /* |
10124 | * See perf_event_ctx_lock() for comments on the details | |
10125 | * of swizzling perf_event::ctx. | |
10126 | */ | |
10127 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10128 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10129 | event_entry) { | |
45a0e07a | 10130 | perf_remove_from_context(event, 0); |
9a545de0 | 10131 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10132 | put_ctx(src_ctx); |
9886167d | 10133 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10134 | } |
0cda4c02 | 10135 | |
8f95b435 PZI |
10136 | /* |
10137 | * Wait for the events to quiesce before re-instating them. | |
10138 | */ | |
0cda4c02 YZ |
10139 | synchronize_rcu(); |
10140 | ||
8f95b435 PZI |
10141 | /* |
10142 | * Re-instate events in 2 passes. | |
10143 | * | |
10144 | * Skip over group leaders and only install siblings on this first | |
10145 | * pass, siblings will not get enabled without a leader, however a | |
10146 | * leader will enable its siblings, even if those are still on the old | |
10147 | * context. | |
10148 | */ | |
10149 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10150 | if (event->group_leader == event) | |
10151 | continue; | |
10152 | ||
10153 | list_del(&event->migrate_entry); | |
10154 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10155 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10156 | account_event_cpu(event, dst_cpu); | |
10157 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10158 | get_ctx(dst_ctx); | |
10159 | } | |
10160 | ||
10161 | /* | |
10162 | * Once all the siblings are setup properly, install the group leaders | |
10163 | * to make it go. | |
10164 | */ | |
9886167d PZ |
10165 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10166 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10167 | if (event->state >= PERF_EVENT_STATE_OFF) |
10168 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10169 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10170 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10171 | get_ctx(dst_ctx); | |
10172 | } | |
10173 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10174 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10175 | } |
10176 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10177 | ||
cdd6c482 | 10178 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10179 | struct task_struct *child) |
d859e29f | 10180 | { |
cdd6c482 | 10181 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10182 | u64 child_val; |
d859e29f | 10183 | |
cdd6c482 IM |
10184 | if (child_event->attr.inherit_stat) |
10185 | perf_event_read_event(child_event, child); | |
38b200d6 | 10186 | |
b5e58793 | 10187 | child_val = perf_event_count(child_event); |
d859e29f PM |
10188 | |
10189 | /* | |
10190 | * Add back the child's count to the parent's count: | |
10191 | */ | |
a6e6dea6 | 10192 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10193 | atomic64_add(child_event->total_time_enabled, |
10194 | &parent_event->child_total_time_enabled); | |
10195 | atomic64_add(child_event->total_time_running, | |
10196 | &parent_event->child_total_time_running); | |
d859e29f PM |
10197 | } |
10198 | ||
9b51f66d | 10199 | static void |
8ba289b8 PZ |
10200 | perf_event_exit_event(struct perf_event *child_event, |
10201 | struct perf_event_context *child_ctx, | |
10202 | struct task_struct *child) | |
9b51f66d | 10203 | { |
8ba289b8 PZ |
10204 | struct perf_event *parent_event = child_event->parent; |
10205 | ||
1903d50c PZ |
10206 | /* |
10207 | * Do not destroy the 'original' grouping; because of the context | |
10208 | * switch optimization the original events could've ended up in a | |
10209 | * random child task. | |
10210 | * | |
10211 | * If we were to destroy the original group, all group related | |
10212 | * operations would cease to function properly after this random | |
10213 | * child dies. | |
10214 | * | |
10215 | * Do destroy all inherited groups, we don't care about those | |
10216 | * and being thorough is better. | |
10217 | */ | |
32132a3d PZ |
10218 | raw_spin_lock_irq(&child_ctx->lock); |
10219 | WARN_ON_ONCE(child_ctx->is_active); | |
10220 | ||
8ba289b8 | 10221 | if (parent_event) |
32132a3d PZ |
10222 | perf_group_detach(child_event); |
10223 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 10224 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 10225 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10226 | |
9b51f66d | 10227 | /* |
8ba289b8 | 10228 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10229 | */ |
8ba289b8 | 10230 | if (!parent_event) { |
179033b3 | 10231 | perf_event_wakeup(child_event); |
8ba289b8 | 10232 | return; |
4bcf349a | 10233 | } |
8ba289b8 PZ |
10234 | /* |
10235 | * Child events can be cleaned up. | |
10236 | */ | |
10237 | ||
10238 | sync_child_event(child_event, child); | |
10239 | ||
10240 | /* | |
10241 | * Remove this event from the parent's list | |
10242 | */ | |
10243 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10244 | mutex_lock(&parent_event->child_mutex); | |
10245 | list_del_init(&child_event->child_list); | |
10246 | mutex_unlock(&parent_event->child_mutex); | |
10247 | ||
10248 | /* | |
10249 | * Kick perf_poll() for is_event_hup(). | |
10250 | */ | |
10251 | perf_event_wakeup(parent_event); | |
10252 | free_event(child_event); | |
10253 | put_event(parent_event); | |
9b51f66d IM |
10254 | } |
10255 | ||
8dc85d54 | 10256 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10257 | { |
211de6eb | 10258 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10259 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10260 | |
10261 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10262 | |
6a3351b6 | 10263 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10264 | if (!child_ctx) |
9b51f66d IM |
10265 | return; |
10266 | ||
ad3a37de | 10267 | /* |
6a3351b6 PZ |
10268 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10269 | * ctx::mutex over the entire thing. This serializes against almost | |
10270 | * everything that wants to access the ctx. | |
10271 | * | |
10272 | * The exception is sys_perf_event_open() / | |
10273 | * perf_event_create_kernel_count() which does find_get_context() | |
10274 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10275 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10276 | */ |
6a3351b6 | 10277 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10278 | |
10279 | /* | |
6a3351b6 PZ |
10280 | * In a single ctx::lock section, de-schedule the events and detach the |
10281 | * context from the task such that we cannot ever get it scheduled back | |
10282 | * in. | |
c93f7669 | 10283 | */ |
6a3351b6 | 10284 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 10285 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 10286 | |
71a851b4 | 10287 | /* |
63b6da39 PZ |
10288 | * Now that the context is inactive, destroy the task <-> ctx relation |
10289 | * and mark the context dead. | |
71a851b4 | 10290 | */ |
63b6da39 PZ |
10291 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10292 | put_ctx(child_ctx); /* cannot be last */ | |
10293 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10294 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10295 | |
211de6eb | 10296 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10297 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10298 | |
211de6eb PZ |
10299 | if (clone_ctx) |
10300 | put_ctx(clone_ctx); | |
4a1c0f26 | 10301 | |
9f498cc5 | 10302 | /* |
cdd6c482 IM |
10303 | * Report the task dead after unscheduling the events so that we |
10304 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10305 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10306 | */ |
cdd6c482 | 10307 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10308 | |
ebf905fc | 10309 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10310 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10311 | |
a63eaf34 PM |
10312 | mutex_unlock(&child_ctx->mutex); |
10313 | ||
10314 | put_ctx(child_ctx); | |
9b51f66d IM |
10315 | } |
10316 | ||
8dc85d54 PZ |
10317 | /* |
10318 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10319 | * |
10320 | * Can be called with cred_guard_mutex held when called from | |
10321 | * install_exec_creds(). | |
8dc85d54 PZ |
10322 | */ |
10323 | void perf_event_exit_task(struct task_struct *child) | |
10324 | { | |
8882135b | 10325 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10326 | int ctxn; |
10327 | ||
8882135b PZ |
10328 | mutex_lock(&child->perf_event_mutex); |
10329 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10330 | owner_entry) { | |
10331 | list_del_init(&event->owner_entry); | |
10332 | ||
10333 | /* | |
10334 | * Ensure the list deletion is visible before we clear | |
10335 | * the owner, closes a race against perf_release() where | |
10336 | * we need to serialize on the owner->perf_event_mutex. | |
10337 | */ | |
f47c02c0 | 10338 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10339 | } |
10340 | mutex_unlock(&child->perf_event_mutex); | |
10341 | ||
8dc85d54 PZ |
10342 | for_each_task_context_nr(ctxn) |
10343 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10344 | |
10345 | /* | |
10346 | * The perf_event_exit_task_context calls perf_event_task | |
10347 | * with child's task_ctx, which generates EXIT events for | |
10348 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10349 | * At this point we need to send EXIT events to cpu contexts. | |
10350 | */ | |
10351 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10352 | } |
10353 | ||
889ff015 FW |
10354 | static void perf_free_event(struct perf_event *event, |
10355 | struct perf_event_context *ctx) | |
10356 | { | |
10357 | struct perf_event *parent = event->parent; | |
10358 | ||
10359 | if (WARN_ON_ONCE(!parent)) | |
10360 | return; | |
10361 | ||
10362 | mutex_lock(&parent->child_mutex); | |
10363 | list_del_init(&event->child_list); | |
10364 | mutex_unlock(&parent->child_mutex); | |
10365 | ||
a6fa941d | 10366 | put_event(parent); |
889ff015 | 10367 | |
652884fe | 10368 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10369 | perf_group_detach(event); |
889ff015 | 10370 | list_del_event(event, ctx); |
652884fe | 10371 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10372 | free_event(event); |
10373 | } | |
10374 | ||
bbbee908 | 10375 | /* |
652884fe | 10376 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10377 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10378 | * |
10379 | * Not all locks are strictly required, but take them anyway to be nice and | |
10380 | * help out with the lockdep assertions. | |
bbbee908 | 10381 | */ |
cdd6c482 | 10382 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10383 | { |
8dc85d54 | 10384 | struct perf_event_context *ctx; |
cdd6c482 | 10385 | struct perf_event *event, *tmp; |
8dc85d54 | 10386 | int ctxn; |
bbbee908 | 10387 | |
8dc85d54 PZ |
10388 | for_each_task_context_nr(ctxn) { |
10389 | ctx = task->perf_event_ctxp[ctxn]; | |
10390 | if (!ctx) | |
10391 | continue; | |
bbbee908 | 10392 | |
8dc85d54 | 10393 | mutex_lock(&ctx->mutex); |
bbbee908 | 10394 | again: |
8dc85d54 PZ |
10395 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
10396 | group_entry) | |
10397 | perf_free_event(event, ctx); | |
bbbee908 | 10398 | |
8dc85d54 PZ |
10399 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
10400 | group_entry) | |
10401 | perf_free_event(event, ctx); | |
bbbee908 | 10402 | |
8dc85d54 PZ |
10403 | if (!list_empty(&ctx->pinned_groups) || |
10404 | !list_empty(&ctx->flexible_groups)) | |
10405 | goto again; | |
bbbee908 | 10406 | |
8dc85d54 | 10407 | mutex_unlock(&ctx->mutex); |
bbbee908 | 10408 | |
8dc85d54 PZ |
10409 | put_ctx(ctx); |
10410 | } | |
889ff015 FW |
10411 | } |
10412 | ||
4e231c79 PZ |
10413 | void perf_event_delayed_put(struct task_struct *task) |
10414 | { | |
10415 | int ctxn; | |
10416 | ||
10417 | for_each_task_context_nr(ctxn) | |
10418 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10419 | } | |
10420 | ||
e03e7ee3 | 10421 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10422 | { |
e03e7ee3 | 10423 | struct file *file; |
ffe8690c | 10424 | |
e03e7ee3 AS |
10425 | file = fget_raw(fd); |
10426 | if (!file) | |
10427 | return ERR_PTR(-EBADF); | |
ffe8690c | 10428 | |
e03e7ee3 AS |
10429 | if (file->f_op != &perf_fops) { |
10430 | fput(file); | |
10431 | return ERR_PTR(-EBADF); | |
10432 | } | |
ffe8690c | 10433 | |
e03e7ee3 | 10434 | return file; |
ffe8690c KX |
10435 | } |
10436 | ||
10437 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10438 | { | |
10439 | if (!event) | |
10440 | return ERR_PTR(-EINVAL); | |
10441 | ||
10442 | return &event->attr; | |
10443 | } | |
10444 | ||
97dee4f3 PZ |
10445 | /* |
10446 | * inherit a event from parent task to child task: | |
10447 | */ | |
10448 | static struct perf_event * | |
10449 | inherit_event(struct perf_event *parent_event, | |
10450 | struct task_struct *parent, | |
10451 | struct perf_event_context *parent_ctx, | |
10452 | struct task_struct *child, | |
10453 | struct perf_event *group_leader, | |
10454 | struct perf_event_context *child_ctx) | |
10455 | { | |
1929def9 | 10456 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10457 | struct perf_event *child_event; |
cee010ec | 10458 | unsigned long flags; |
97dee4f3 PZ |
10459 | |
10460 | /* | |
10461 | * Instead of creating recursive hierarchies of events, | |
10462 | * we link inherited events back to the original parent, | |
10463 | * which has a filp for sure, which we use as the reference | |
10464 | * count: | |
10465 | */ | |
10466 | if (parent_event->parent) | |
10467 | parent_event = parent_event->parent; | |
10468 | ||
10469 | child_event = perf_event_alloc(&parent_event->attr, | |
10470 | parent_event->cpu, | |
d580ff86 | 10471 | child, |
97dee4f3 | 10472 | group_leader, parent_event, |
79dff51e | 10473 | NULL, NULL, -1); |
97dee4f3 PZ |
10474 | if (IS_ERR(child_event)) |
10475 | return child_event; | |
a6fa941d | 10476 | |
c6e5b732 PZ |
10477 | /* |
10478 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10479 | * must be under the same lock in order to serialize against | |
10480 | * perf_event_release_kernel(), such that either we must observe | |
10481 | * is_orphaned_event() or they will observe us on the child_list. | |
10482 | */ | |
10483 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10484 | if (is_orphaned_event(parent_event) || |
10485 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10486 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10487 | free_event(child_event); |
10488 | return NULL; | |
10489 | } | |
10490 | ||
97dee4f3 PZ |
10491 | get_ctx(child_ctx); |
10492 | ||
10493 | /* | |
10494 | * Make the child state follow the state of the parent event, | |
10495 | * not its attr.disabled bit. We hold the parent's mutex, | |
10496 | * so we won't race with perf_event_{en, dis}able_family. | |
10497 | */ | |
1929def9 | 10498 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10499 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10500 | else | |
10501 | child_event->state = PERF_EVENT_STATE_OFF; | |
10502 | ||
10503 | if (parent_event->attr.freq) { | |
10504 | u64 sample_period = parent_event->hw.sample_period; | |
10505 | struct hw_perf_event *hwc = &child_event->hw; | |
10506 | ||
10507 | hwc->sample_period = sample_period; | |
10508 | hwc->last_period = sample_period; | |
10509 | ||
10510 | local64_set(&hwc->period_left, sample_period); | |
10511 | } | |
10512 | ||
10513 | child_event->ctx = child_ctx; | |
10514 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10515 | child_event->overflow_handler_context |
10516 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10517 | |
614b6780 TG |
10518 | /* |
10519 | * Precalculate sample_data sizes | |
10520 | */ | |
10521 | perf_event__header_size(child_event); | |
6844c09d | 10522 | perf_event__id_header_size(child_event); |
614b6780 | 10523 | |
97dee4f3 PZ |
10524 | /* |
10525 | * Link it up in the child's context: | |
10526 | */ | |
cee010ec | 10527 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10528 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10529 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10530 | |
97dee4f3 PZ |
10531 | /* |
10532 | * Link this into the parent event's child list | |
10533 | */ | |
97dee4f3 PZ |
10534 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10535 | mutex_unlock(&parent_event->child_mutex); | |
10536 | ||
10537 | return child_event; | |
10538 | } | |
10539 | ||
10540 | static int inherit_group(struct perf_event *parent_event, | |
10541 | struct task_struct *parent, | |
10542 | struct perf_event_context *parent_ctx, | |
10543 | struct task_struct *child, | |
10544 | struct perf_event_context *child_ctx) | |
10545 | { | |
10546 | struct perf_event *leader; | |
10547 | struct perf_event *sub; | |
10548 | struct perf_event *child_ctr; | |
10549 | ||
10550 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10551 | child, NULL, child_ctx); | |
10552 | if (IS_ERR(leader)) | |
10553 | return PTR_ERR(leader); | |
10554 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
10555 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10556 | child, leader, child_ctx); | |
10557 | if (IS_ERR(child_ctr)) | |
10558 | return PTR_ERR(child_ctr); | |
10559 | } | |
10560 | return 0; | |
889ff015 FW |
10561 | } |
10562 | ||
10563 | static int | |
10564 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10565 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10566 | struct task_struct *child, int ctxn, |
889ff015 FW |
10567 | int *inherited_all) |
10568 | { | |
10569 | int ret; | |
8dc85d54 | 10570 | struct perf_event_context *child_ctx; |
889ff015 FW |
10571 | |
10572 | if (!event->attr.inherit) { | |
10573 | *inherited_all = 0; | |
10574 | return 0; | |
bbbee908 PZ |
10575 | } |
10576 | ||
fe4b04fa | 10577 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10578 | if (!child_ctx) { |
10579 | /* | |
10580 | * This is executed from the parent task context, so | |
10581 | * inherit events that have been marked for cloning. | |
10582 | * First allocate and initialize a context for the | |
10583 | * child. | |
10584 | */ | |
bbbee908 | 10585 | |
734df5ab | 10586 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10587 | if (!child_ctx) |
10588 | return -ENOMEM; | |
bbbee908 | 10589 | |
8dc85d54 | 10590 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10591 | } |
10592 | ||
10593 | ret = inherit_group(event, parent, parent_ctx, | |
10594 | child, child_ctx); | |
10595 | ||
10596 | if (ret) | |
10597 | *inherited_all = 0; | |
10598 | ||
10599 | return ret; | |
bbbee908 PZ |
10600 | } |
10601 | ||
9b51f66d | 10602 | /* |
cdd6c482 | 10603 | * Initialize the perf_event context in task_struct |
9b51f66d | 10604 | */ |
985c8dcb | 10605 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10606 | { |
889ff015 | 10607 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10608 | struct perf_event_context *cloned_ctx; |
10609 | struct perf_event *event; | |
9b51f66d | 10610 | struct task_struct *parent = current; |
564c2b21 | 10611 | int inherited_all = 1; |
dddd3379 | 10612 | unsigned long flags; |
6ab423e0 | 10613 | int ret = 0; |
9b51f66d | 10614 | |
8dc85d54 | 10615 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10616 | return 0; |
10617 | ||
ad3a37de | 10618 | /* |
25346b93 PM |
10619 | * If the parent's context is a clone, pin it so it won't get |
10620 | * swapped under us. | |
ad3a37de | 10621 | */ |
8dc85d54 | 10622 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10623 | if (!parent_ctx) |
10624 | return 0; | |
25346b93 | 10625 | |
ad3a37de PM |
10626 | /* |
10627 | * No need to check if parent_ctx != NULL here; since we saw | |
10628 | * it non-NULL earlier, the only reason for it to become NULL | |
10629 | * is if we exit, and since we're currently in the middle of | |
10630 | * a fork we can't be exiting at the same time. | |
10631 | */ | |
ad3a37de | 10632 | |
9b51f66d IM |
10633 | /* |
10634 | * Lock the parent list. No need to lock the child - not PID | |
10635 | * hashed yet and not running, so nobody can access it. | |
10636 | */ | |
d859e29f | 10637 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10638 | |
10639 | /* | |
10640 | * We dont have to disable NMIs - we are only looking at | |
10641 | * the list, not manipulating it: | |
10642 | */ | |
889ff015 | 10643 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10644 | ret = inherit_task_group(event, parent, parent_ctx, |
10645 | child, ctxn, &inherited_all); | |
889ff015 FW |
10646 | if (ret) |
10647 | break; | |
10648 | } | |
b93f7978 | 10649 | |
dddd3379 TG |
10650 | /* |
10651 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10652 | * to allocations, but we need to prevent rotation because | |
10653 | * rotate_ctx() will change the list from interrupt context. | |
10654 | */ | |
10655 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10656 | parent_ctx->rotate_disable = 1; | |
10657 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10658 | ||
889ff015 | 10659 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10660 | ret = inherit_task_group(event, parent, parent_ctx, |
10661 | child, ctxn, &inherited_all); | |
889ff015 | 10662 | if (ret) |
9b51f66d | 10663 | break; |
564c2b21 PM |
10664 | } |
10665 | ||
dddd3379 TG |
10666 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10667 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10668 | |
8dc85d54 | 10669 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10670 | |
05cbaa28 | 10671 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10672 | /* |
10673 | * Mark the child context as a clone of the parent | |
10674 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10675 | * |
10676 | * Note that if the parent is a clone, the holding of | |
10677 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10678 | */ |
c5ed5145 | 10679 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10680 | if (cloned_ctx) { |
10681 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10682 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10683 | } else { |
10684 | child_ctx->parent_ctx = parent_ctx; | |
10685 | child_ctx->parent_gen = parent_ctx->generation; | |
10686 | } | |
10687 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10688 | } |
10689 | ||
c5ed5145 | 10690 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 10691 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10692 | |
25346b93 | 10693 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10694 | put_ctx(parent_ctx); |
ad3a37de | 10695 | |
6ab423e0 | 10696 | return ret; |
9b51f66d IM |
10697 | } |
10698 | ||
8dc85d54 PZ |
10699 | /* |
10700 | * Initialize the perf_event context in task_struct | |
10701 | */ | |
10702 | int perf_event_init_task(struct task_struct *child) | |
10703 | { | |
10704 | int ctxn, ret; | |
10705 | ||
8550d7cb ON |
10706 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10707 | mutex_init(&child->perf_event_mutex); | |
10708 | INIT_LIST_HEAD(&child->perf_event_list); | |
10709 | ||
8dc85d54 PZ |
10710 | for_each_task_context_nr(ctxn) { |
10711 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10712 | if (ret) { |
10713 | perf_event_free_task(child); | |
8dc85d54 | 10714 | return ret; |
6c72e350 | 10715 | } |
8dc85d54 PZ |
10716 | } |
10717 | ||
10718 | return 0; | |
10719 | } | |
10720 | ||
220b140b PM |
10721 | static void __init perf_event_init_all_cpus(void) |
10722 | { | |
b28ab83c | 10723 | struct swevent_htable *swhash; |
220b140b | 10724 | int cpu; |
220b140b PM |
10725 | |
10726 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10727 | swhash = &per_cpu(swevent_htable, cpu); |
10728 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10729 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10730 | |
10731 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10732 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 10733 | |
058fe1c0 DCC |
10734 | #ifdef CONFIG_CGROUP_PERF |
10735 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
10736 | #endif | |
e48c1788 | 10737 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
10738 | } |
10739 | } | |
10740 | ||
00e16c3d | 10741 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10742 | { |
108b02cf | 10743 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10744 | |
b28ab83c | 10745 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10746 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10747 | struct swevent_hlist *hlist; |
10748 | ||
b28ab83c PZ |
10749 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10750 | WARN_ON(!hlist); | |
10751 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10752 | } |
b28ab83c | 10753 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10754 | return 0; |
0793a61d TG |
10755 | } |
10756 | ||
2965faa5 | 10757 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10758 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10759 | { |
108b02cf | 10760 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10761 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10762 | struct perf_event *event; | |
0793a61d | 10763 | |
fae3fde6 PZ |
10764 | raw_spin_lock(&ctx->lock); |
10765 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10766 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10767 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10768 | } |
108b02cf PZ |
10769 | |
10770 | static void perf_event_exit_cpu_context(int cpu) | |
10771 | { | |
10772 | struct perf_event_context *ctx; | |
10773 | struct pmu *pmu; | |
10774 | int idx; | |
10775 | ||
10776 | idx = srcu_read_lock(&pmus_srcu); | |
10777 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10778 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10779 | |
10780 | mutex_lock(&ctx->mutex); | |
10781 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10782 | mutex_unlock(&ctx->mutex); | |
10783 | } | |
10784 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10785 | } |
00e16c3d TG |
10786 | #else |
10787 | ||
10788 | static void perf_event_exit_cpu_context(int cpu) { } | |
10789 | ||
10790 | #endif | |
108b02cf | 10791 | |
00e16c3d | 10792 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10793 | { |
e3703f8c | 10794 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10795 | return 0; |
0793a61d | 10796 | } |
0793a61d | 10797 | |
c277443c PZ |
10798 | static int |
10799 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10800 | { | |
10801 | int cpu; | |
10802 | ||
10803 | for_each_online_cpu(cpu) | |
10804 | perf_event_exit_cpu(cpu); | |
10805 | ||
10806 | return NOTIFY_OK; | |
10807 | } | |
10808 | ||
10809 | /* | |
10810 | * Run the perf reboot notifier at the very last possible moment so that | |
10811 | * the generic watchdog code runs as long as possible. | |
10812 | */ | |
10813 | static struct notifier_block perf_reboot_notifier = { | |
10814 | .notifier_call = perf_reboot, | |
10815 | .priority = INT_MIN, | |
10816 | }; | |
10817 | ||
cdd6c482 | 10818 | void __init perf_event_init(void) |
0793a61d | 10819 | { |
3c502e7a JW |
10820 | int ret; |
10821 | ||
2e80a82a PZ |
10822 | idr_init(&pmu_idr); |
10823 | ||
220b140b | 10824 | perf_event_init_all_cpus(); |
b0a873eb | 10825 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
10826 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
10827 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
10828 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 10829 | perf_tp_register(); |
00e16c3d | 10830 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 10831 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
10832 | |
10833 | ret = init_hw_breakpoint(); | |
10834 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 10835 | |
b01c3a00 JO |
10836 | /* |
10837 | * Build time assertion that we keep the data_head at the intended | |
10838 | * location. IOW, validation we got the __reserved[] size right. | |
10839 | */ | |
10840 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
10841 | != 1024); | |
0793a61d | 10842 | } |
abe43400 | 10843 | |
fd979c01 CS |
10844 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
10845 | char *page) | |
10846 | { | |
10847 | struct perf_pmu_events_attr *pmu_attr = | |
10848 | container_of(attr, struct perf_pmu_events_attr, attr); | |
10849 | ||
10850 | if (pmu_attr->event_str) | |
10851 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
10852 | ||
10853 | return 0; | |
10854 | } | |
675965b0 | 10855 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 10856 | |
abe43400 PZ |
10857 | static int __init perf_event_sysfs_init(void) |
10858 | { | |
10859 | struct pmu *pmu; | |
10860 | int ret; | |
10861 | ||
10862 | mutex_lock(&pmus_lock); | |
10863 | ||
10864 | ret = bus_register(&pmu_bus); | |
10865 | if (ret) | |
10866 | goto unlock; | |
10867 | ||
10868 | list_for_each_entry(pmu, &pmus, entry) { | |
10869 | if (!pmu->name || pmu->type < 0) | |
10870 | continue; | |
10871 | ||
10872 | ret = pmu_dev_alloc(pmu); | |
10873 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
10874 | } | |
10875 | pmu_bus_running = 1; | |
10876 | ret = 0; | |
10877 | ||
10878 | unlock: | |
10879 | mutex_unlock(&pmus_lock); | |
10880 | ||
10881 | return ret; | |
10882 | } | |
10883 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
10884 | |
10885 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
10886 | static struct cgroup_subsys_state * |
10887 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
10888 | { |
10889 | struct perf_cgroup *jc; | |
e5d1367f | 10890 | |
1b15d055 | 10891 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
10892 | if (!jc) |
10893 | return ERR_PTR(-ENOMEM); | |
10894 | ||
e5d1367f SE |
10895 | jc->info = alloc_percpu(struct perf_cgroup_info); |
10896 | if (!jc->info) { | |
10897 | kfree(jc); | |
10898 | return ERR_PTR(-ENOMEM); | |
10899 | } | |
10900 | ||
e5d1367f SE |
10901 | return &jc->css; |
10902 | } | |
10903 | ||
eb95419b | 10904 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 10905 | { |
eb95419b TH |
10906 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
10907 | ||
e5d1367f SE |
10908 | free_percpu(jc->info); |
10909 | kfree(jc); | |
10910 | } | |
10911 | ||
10912 | static int __perf_cgroup_move(void *info) | |
10913 | { | |
10914 | struct task_struct *task = info; | |
ddaaf4e2 | 10915 | rcu_read_lock(); |
e5d1367f | 10916 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 10917 | rcu_read_unlock(); |
e5d1367f SE |
10918 | return 0; |
10919 | } | |
10920 | ||
1f7dd3e5 | 10921 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 10922 | { |
bb9d97b6 | 10923 | struct task_struct *task; |
1f7dd3e5 | 10924 | struct cgroup_subsys_state *css; |
bb9d97b6 | 10925 | |
1f7dd3e5 | 10926 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 10927 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
10928 | } |
10929 | ||
073219e9 | 10930 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
10931 | .css_alloc = perf_cgroup_css_alloc, |
10932 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 10933 | .attach = perf_cgroup_attach, |
e5d1367f SE |
10934 | }; |
10935 | #endif /* CONFIG_CGROUP_PERF */ |