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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> | |
e6017571 | 49 | #include <linux/sched/clock.h> |
6e84f315 | 50 | #include <linux/sched/mm.h> |
e4222673 HB |
51 | #include <linux/proc_ns.h> |
52 | #include <linux/mount.h> | |
0793a61d | 53 | |
76369139 FW |
54 | #include "internal.h" |
55 | ||
4e193bd4 TB |
56 | #include <asm/irq_regs.h> |
57 | ||
272325c4 PZ |
58 | typedef int (*remote_function_f)(void *); |
59 | ||
fe4b04fa | 60 | struct remote_function_call { |
e7e7ee2e | 61 | struct task_struct *p; |
272325c4 | 62 | remote_function_f func; |
e7e7ee2e IM |
63 | void *info; |
64 | int ret; | |
fe4b04fa PZ |
65 | }; |
66 | ||
67 | static void remote_function(void *data) | |
68 | { | |
69 | struct remote_function_call *tfc = data; | |
70 | struct task_struct *p = tfc->p; | |
71 | ||
72 | if (p) { | |
0da4cf3e PZ |
73 | /* -EAGAIN */ |
74 | if (task_cpu(p) != smp_processor_id()) | |
75 | return; | |
76 | ||
77 | /* | |
78 | * Now that we're on right CPU with IRQs disabled, we can test | |
79 | * if we hit the right task without races. | |
80 | */ | |
81 | ||
82 | tfc->ret = -ESRCH; /* No such (running) process */ | |
83 | if (p != current) | |
fe4b04fa PZ |
84 | return; |
85 | } | |
86 | ||
87 | tfc->ret = tfc->func(tfc->info); | |
88 | } | |
89 | ||
90 | /** | |
91 | * task_function_call - call a function on the cpu on which a task runs | |
92 | * @p: the task to evaluate | |
93 | * @func: the function to be called | |
94 | * @info: the function call argument | |
95 | * | |
96 | * Calls the function @func when the task is currently running. This might | |
97 | * be on the current CPU, which just calls the function directly | |
98 | * | |
99 | * returns: @func return value, or | |
100 | * -ESRCH - when the process isn't running | |
101 | * -EAGAIN - when the process moved away | |
102 | */ | |
103 | static int | |
272325c4 | 104 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
105 | { |
106 | struct remote_function_call data = { | |
e7e7ee2e IM |
107 | .p = p, |
108 | .func = func, | |
109 | .info = info, | |
0da4cf3e | 110 | .ret = -EAGAIN, |
fe4b04fa | 111 | }; |
0da4cf3e | 112 | int ret; |
fe4b04fa | 113 | |
0da4cf3e PZ |
114 | do { |
115 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
116 | if (!ret) | |
117 | ret = data.ret; | |
118 | } while (ret == -EAGAIN); | |
fe4b04fa | 119 | |
0da4cf3e | 120 | return ret; |
fe4b04fa PZ |
121 | } |
122 | ||
123 | /** | |
124 | * cpu_function_call - call a function on the cpu | |
125 | * @func: the function to be called | |
126 | * @info: the function call argument | |
127 | * | |
128 | * Calls the function @func on the remote cpu. | |
129 | * | |
130 | * returns: @func return value or -ENXIO when the cpu is offline | |
131 | */ | |
272325c4 | 132 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
133 | { |
134 | struct remote_function_call data = { | |
e7e7ee2e IM |
135 | .p = NULL, |
136 | .func = func, | |
137 | .info = info, | |
138 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
139 | }; |
140 | ||
141 | smp_call_function_single(cpu, remote_function, &data, 1); | |
142 | ||
143 | return data.ret; | |
144 | } | |
145 | ||
fae3fde6 PZ |
146 | static inline struct perf_cpu_context * |
147 | __get_cpu_context(struct perf_event_context *ctx) | |
148 | { | |
149 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
150 | } | |
151 | ||
152 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
153 | struct perf_event_context *ctx) | |
0017960f | 154 | { |
fae3fde6 PZ |
155 | raw_spin_lock(&cpuctx->ctx.lock); |
156 | if (ctx) | |
157 | raw_spin_lock(&ctx->lock); | |
158 | } | |
159 | ||
160 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
161 | struct perf_event_context *ctx) | |
162 | { | |
163 | if (ctx) | |
164 | raw_spin_unlock(&ctx->lock); | |
165 | raw_spin_unlock(&cpuctx->ctx.lock); | |
166 | } | |
167 | ||
63b6da39 PZ |
168 | #define TASK_TOMBSTONE ((void *)-1L) |
169 | ||
170 | static bool is_kernel_event(struct perf_event *event) | |
171 | { | |
f47c02c0 | 172 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
173 | } |
174 | ||
39a43640 PZ |
175 | /* |
176 | * On task ctx scheduling... | |
177 | * | |
178 | * When !ctx->nr_events a task context will not be scheduled. This means | |
179 | * we can disable the scheduler hooks (for performance) without leaving | |
180 | * pending task ctx state. | |
181 | * | |
182 | * This however results in two special cases: | |
183 | * | |
184 | * - removing the last event from a task ctx; this is relatively straight | |
185 | * forward and is done in __perf_remove_from_context. | |
186 | * | |
187 | * - adding the first event to a task ctx; this is tricky because we cannot | |
188 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
189 | * See perf_install_in_context(). | |
190 | * | |
39a43640 PZ |
191 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
192 | */ | |
193 | ||
fae3fde6 PZ |
194 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
195 | struct perf_event_context *, void *); | |
196 | ||
197 | struct event_function_struct { | |
198 | struct perf_event *event; | |
199 | event_f func; | |
200 | void *data; | |
201 | }; | |
202 | ||
203 | static int event_function(void *info) | |
204 | { | |
205 | struct event_function_struct *efs = info; | |
206 | struct perf_event *event = efs->event; | |
0017960f | 207 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
208 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
209 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 210 | int ret = 0; |
fae3fde6 PZ |
211 | |
212 | WARN_ON_ONCE(!irqs_disabled()); | |
213 | ||
63b6da39 | 214 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
215 | /* |
216 | * Since we do the IPI call without holding ctx->lock things can have | |
217 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
218 | */ |
219 | if (ctx->task) { | |
63b6da39 | 220 | if (ctx->task != current) { |
0da4cf3e | 221 | ret = -ESRCH; |
63b6da39 PZ |
222 | goto unlock; |
223 | } | |
fae3fde6 | 224 | |
fae3fde6 PZ |
225 | /* |
226 | * We only use event_function_call() on established contexts, | |
227 | * and event_function() is only ever called when active (or | |
228 | * rather, we'll have bailed in task_function_call() or the | |
229 | * above ctx->task != current test), therefore we must have | |
230 | * ctx->is_active here. | |
231 | */ | |
232 | WARN_ON_ONCE(!ctx->is_active); | |
233 | /* | |
234 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
235 | * match. | |
236 | */ | |
63b6da39 PZ |
237 | WARN_ON_ONCE(task_ctx != ctx); |
238 | } else { | |
239 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 240 | } |
63b6da39 | 241 | |
fae3fde6 | 242 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 243 | unlock: |
fae3fde6 PZ |
244 | perf_ctx_unlock(cpuctx, task_ctx); |
245 | ||
63b6da39 | 246 | return ret; |
fae3fde6 PZ |
247 | } |
248 | ||
fae3fde6 | 249 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
250 | { |
251 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 252 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
253 | struct event_function_struct efs = { |
254 | .event = event, | |
255 | .func = func, | |
256 | .data = data, | |
257 | }; | |
0017960f | 258 | |
c97f4736 PZ |
259 | if (!event->parent) { |
260 | /* | |
261 | * If this is a !child event, we must hold ctx::mutex to | |
262 | * stabilize the the event->ctx relation. See | |
263 | * perf_event_ctx_lock(). | |
264 | */ | |
265 | lockdep_assert_held(&ctx->mutex); | |
266 | } | |
0017960f PZ |
267 | |
268 | if (!task) { | |
fae3fde6 | 269 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
270 | return; |
271 | } | |
272 | ||
63b6da39 PZ |
273 | if (task == TASK_TOMBSTONE) |
274 | return; | |
275 | ||
a096309b | 276 | again: |
fae3fde6 | 277 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
278 | return; |
279 | ||
280 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
281 | /* |
282 | * Reload the task pointer, it might have been changed by | |
283 | * a concurrent perf_event_context_sched_out(). | |
284 | */ | |
285 | task = ctx->task; | |
a096309b PZ |
286 | if (task == TASK_TOMBSTONE) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | return; | |
0017960f | 289 | } |
a096309b PZ |
290 | if (ctx->is_active) { |
291 | raw_spin_unlock_irq(&ctx->lock); | |
292 | goto again; | |
293 | } | |
294 | func(event, NULL, ctx, data); | |
0017960f PZ |
295 | raw_spin_unlock_irq(&ctx->lock); |
296 | } | |
297 | ||
cca20946 PZ |
298 | /* |
299 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
300 | * are already disabled and we're on the right CPU. | |
301 | */ | |
302 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
303 | { | |
304 | struct perf_event_context *ctx = event->ctx; | |
305 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
306 | struct task_struct *task = READ_ONCE(ctx->task); | |
307 | struct perf_event_context *task_ctx = NULL; | |
308 | ||
309 | WARN_ON_ONCE(!irqs_disabled()); | |
310 | ||
311 | if (task) { | |
312 | if (task == TASK_TOMBSTONE) | |
313 | return; | |
314 | ||
315 | task_ctx = ctx; | |
316 | } | |
317 | ||
318 | perf_ctx_lock(cpuctx, task_ctx); | |
319 | ||
320 | task = ctx->task; | |
321 | if (task == TASK_TOMBSTONE) | |
322 | goto unlock; | |
323 | ||
324 | if (task) { | |
325 | /* | |
326 | * We must be either inactive or active and the right task, | |
327 | * otherwise we're screwed, since we cannot IPI to somewhere | |
328 | * else. | |
329 | */ | |
330 | if (ctx->is_active) { | |
331 | if (WARN_ON_ONCE(task != current)) | |
332 | goto unlock; | |
333 | ||
334 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
335 | goto unlock; | |
336 | } | |
337 | } else { | |
338 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
339 | } | |
340 | ||
341 | func(event, cpuctx, ctx, data); | |
342 | unlock: | |
343 | perf_ctx_unlock(cpuctx, task_ctx); | |
344 | } | |
345 | ||
e5d1367f SE |
346 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
347 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
348 | PERF_FLAG_PID_CGROUP |\ |
349 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 350 | |
bce38cd5 SE |
351 | /* |
352 | * branch priv levels that need permission checks | |
353 | */ | |
354 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
355 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
356 | PERF_SAMPLE_BRANCH_HV) | |
357 | ||
0b3fcf17 SE |
358 | enum event_type_t { |
359 | EVENT_FLEXIBLE = 0x1, | |
360 | EVENT_PINNED = 0x2, | |
3cbaa590 | 361 | EVENT_TIME = 0x4, |
487f05e1 AS |
362 | /* see ctx_resched() for details */ |
363 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
364 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
365 | }; | |
366 | ||
e5d1367f SE |
367 | /* |
368 | * perf_sched_events : >0 events exist | |
369 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
370 | */ | |
9107c89e PZ |
371 | |
372 | static void perf_sched_delayed(struct work_struct *work); | |
373 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
374 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
375 | static DEFINE_MUTEX(perf_sched_mutex); | |
376 | static atomic_t perf_sched_count; | |
377 | ||
e5d1367f | 378 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 379 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 380 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 381 | |
cdd6c482 IM |
382 | static atomic_t nr_mmap_events __read_mostly; |
383 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 384 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 385 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 386 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 387 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 388 | |
108b02cf PZ |
389 | static LIST_HEAD(pmus); |
390 | static DEFINE_MUTEX(pmus_lock); | |
391 | static struct srcu_struct pmus_srcu; | |
392 | ||
0764771d | 393 | /* |
cdd6c482 | 394 | * perf event paranoia level: |
0fbdea19 IM |
395 | * -1 - not paranoid at all |
396 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 397 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 398 | * 2 - disallow kernel profiling for unpriv |
0764771d | 399 | */ |
0161028b | 400 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 401 | |
20443384 FW |
402 | /* Minimum for 512 kiB + 1 user control page */ |
403 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
404 | |
405 | /* | |
cdd6c482 | 406 | * max perf event sample rate |
df58ab24 | 407 | */ |
14c63f17 DH |
408 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
409 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
410 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
411 | ||
412 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
413 | ||
414 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
415 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
416 | ||
d9494cb4 PZ |
417 | static int perf_sample_allowed_ns __read_mostly = |
418 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 419 | |
18ab2cd3 | 420 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
421 | { |
422 | u64 tmp = perf_sample_period_ns; | |
423 | ||
424 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
425 | tmp = div_u64(tmp, 100); |
426 | if (!tmp) | |
427 | tmp = 1; | |
428 | ||
429 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 430 | } |
163ec435 | 431 | |
9e630205 SE |
432 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
433 | ||
163ec435 PZ |
434 | int perf_proc_update_handler(struct ctl_table *table, int write, |
435 | void __user *buffer, size_t *lenp, | |
436 | loff_t *ppos) | |
437 | { | |
723478c8 | 438 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
439 | |
440 | if (ret || !write) | |
441 | return ret; | |
442 | ||
ab7fdefb KL |
443 | /* |
444 | * If throttling is disabled don't allow the write: | |
445 | */ | |
446 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
447 | sysctl_perf_cpu_time_max_percent == 0) | |
448 | return -EINVAL; | |
449 | ||
163ec435 | 450 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
451 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
452 | update_perf_cpu_limits(); | |
453 | ||
454 | return 0; | |
455 | } | |
456 | ||
457 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
458 | ||
459 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
460 | void __user *buffer, size_t *lenp, | |
461 | loff_t *ppos) | |
462 | { | |
1572e45a | 463 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
464 | |
465 | if (ret || !write) | |
466 | return ret; | |
467 | ||
b303e7c1 PZ |
468 | if (sysctl_perf_cpu_time_max_percent == 100 || |
469 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
470 | printk(KERN_WARNING |
471 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
472 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
473 | } else { | |
474 | update_perf_cpu_limits(); | |
475 | } | |
163ec435 PZ |
476 | |
477 | return 0; | |
478 | } | |
1ccd1549 | 479 | |
14c63f17 DH |
480 | /* |
481 | * perf samples are done in some very critical code paths (NMIs). | |
482 | * If they take too much CPU time, the system can lock up and not | |
483 | * get any real work done. This will drop the sample rate when | |
484 | * we detect that events are taking too long. | |
485 | */ | |
486 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 487 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 488 | |
91a612ee PZ |
489 | static u64 __report_avg; |
490 | static u64 __report_allowed; | |
491 | ||
6a02ad66 | 492 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 493 | { |
0d87d7ec | 494 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
495 | "perf: interrupt took too long (%lld > %lld), lowering " |
496 | "kernel.perf_event_max_sample_rate to %d\n", | |
497 | __report_avg, __report_allowed, | |
498 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
499 | } |
500 | ||
501 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
502 | ||
503 | void perf_sample_event_took(u64 sample_len_ns) | |
504 | { | |
91a612ee PZ |
505 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
506 | u64 running_len; | |
507 | u64 avg_len; | |
508 | u32 max; | |
14c63f17 | 509 | |
91a612ee | 510 | if (max_len == 0) |
14c63f17 DH |
511 | return; |
512 | ||
91a612ee PZ |
513 | /* Decay the counter by 1 average sample. */ |
514 | running_len = __this_cpu_read(running_sample_length); | |
515 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
516 | running_len += sample_len_ns; | |
517 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
518 | |
519 | /* | |
91a612ee PZ |
520 | * Note: this will be biased artifically low until we have |
521 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
522 | * from having to maintain a count. |
523 | */ | |
91a612ee PZ |
524 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
525 | if (avg_len <= max_len) | |
14c63f17 DH |
526 | return; |
527 | ||
91a612ee PZ |
528 | __report_avg = avg_len; |
529 | __report_allowed = max_len; | |
14c63f17 | 530 | |
91a612ee PZ |
531 | /* |
532 | * Compute a throttle threshold 25% below the current duration. | |
533 | */ | |
534 | avg_len += avg_len / 4; | |
535 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
536 | if (avg_len < max) | |
537 | max /= (u32)avg_len; | |
538 | else | |
539 | max = 1; | |
14c63f17 | 540 | |
91a612ee PZ |
541 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
542 | WRITE_ONCE(max_samples_per_tick, max); | |
543 | ||
544 | sysctl_perf_event_sample_rate = max * HZ; | |
545 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 546 | |
cd578abb | 547 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 548 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 549 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 550 | __report_avg, __report_allowed, |
cd578abb PZ |
551 | sysctl_perf_event_sample_rate); |
552 | } | |
14c63f17 DH |
553 | } |
554 | ||
cdd6c482 | 555 | static atomic64_t perf_event_id; |
a96bbc16 | 556 | |
0b3fcf17 SE |
557 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
558 | enum event_type_t event_type); | |
559 | ||
560 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
561 | enum event_type_t event_type, |
562 | struct task_struct *task); | |
563 | ||
564 | static void update_context_time(struct perf_event_context *ctx); | |
565 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 566 | |
cdd6c482 | 567 | void __weak perf_event_print_debug(void) { } |
0793a61d | 568 | |
84c79910 | 569 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 570 | { |
84c79910 | 571 | return "pmu"; |
0793a61d TG |
572 | } |
573 | ||
0b3fcf17 SE |
574 | static inline u64 perf_clock(void) |
575 | { | |
576 | return local_clock(); | |
577 | } | |
578 | ||
34f43927 PZ |
579 | static inline u64 perf_event_clock(struct perf_event *event) |
580 | { | |
581 | return event->clock(); | |
582 | } | |
583 | ||
e5d1367f SE |
584 | #ifdef CONFIG_CGROUP_PERF |
585 | ||
e5d1367f SE |
586 | static inline bool |
587 | perf_cgroup_match(struct perf_event *event) | |
588 | { | |
589 | struct perf_event_context *ctx = event->ctx; | |
590 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
591 | ||
ef824fa1 TH |
592 | /* @event doesn't care about cgroup */ |
593 | if (!event->cgrp) | |
594 | return true; | |
595 | ||
596 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
597 | if (!cpuctx->cgrp) | |
598 | return false; | |
599 | ||
600 | /* | |
601 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
602 | * also enabled for all its descendant cgroups. If @cpuctx's | |
603 | * cgroup is a descendant of @event's (the test covers identity | |
604 | * case), it's a match. | |
605 | */ | |
606 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
607 | event->cgrp->css.cgroup); | |
e5d1367f SE |
608 | } |
609 | ||
e5d1367f SE |
610 | static inline void perf_detach_cgroup(struct perf_event *event) |
611 | { | |
4e2ba650 | 612 | css_put(&event->cgrp->css); |
e5d1367f SE |
613 | event->cgrp = NULL; |
614 | } | |
615 | ||
616 | static inline int is_cgroup_event(struct perf_event *event) | |
617 | { | |
618 | return event->cgrp != NULL; | |
619 | } | |
620 | ||
621 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
622 | { | |
623 | struct perf_cgroup_info *t; | |
624 | ||
625 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
626 | return t->time; | |
627 | } | |
628 | ||
629 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
630 | { | |
631 | struct perf_cgroup_info *info; | |
632 | u64 now; | |
633 | ||
634 | now = perf_clock(); | |
635 | ||
636 | info = this_cpu_ptr(cgrp->info); | |
637 | ||
638 | info->time += now - info->timestamp; | |
639 | info->timestamp = now; | |
640 | } | |
641 | ||
642 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
643 | { | |
644 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
645 | if (cgrp_out) | |
646 | __update_cgrp_time(cgrp_out); | |
647 | } | |
648 | ||
649 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
650 | { | |
3f7cce3c SE |
651 | struct perf_cgroup *cgrp; |
652 | ||
e5d1367f | 653 | /* |
3f7cce3c SE |
654 | * ensure we access cgroup data only when needed and |
655 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 656 | */ |
3f7cce3c | 657 | if (!is_cgroup_event(event)) |
e5d1367f SE |
658 | return; |
659 | ||
614e4c4e | 660 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
661 | /* |
662 | * Do not update time when cgroup is not active | |
663 | */ | |
664 | if (cgrp == event->cgrp) | |
665 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
666 | } |
667 | ||
668 | static inline void | |
3f7cce3c SE |
669 | perf_cgroup_set_timestamp(struct task_struct *task, |
670 | struct perf_event_context *ctx) | |
e5d1367f SE |
671 | { |
672 | struct perf_cgroup *cgrp; | |
673 | struct perf_cgroup_info *info; | |
674 | ||
3f7cce3c SE |
675 | /* |
676 | * ctx->lock held by caller | |
677 | * ensure we do not access cgroup data | |
678 | * unless we have the cgroup pinned (css_get) | |
679 | */ | |
680 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
681 | return; |
682 | ||
614e4c4e | 683 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 684 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 685 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
686 | } |
687 | ||
058fe1c0 DCC |
688 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
689 | ||
e5d1367f SE |
690 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
691 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
692 | ||
693 | /* | |
694 | * reschedule events based on the cgroup constraint of task. | |
695 | * | |
696 | * mode SWOUT : schedule out everything | |
697 | * mode SWIN : schedule in based on cgroup for next | |
698 | */ | |
18ab2cd3 | 699 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
700 | { |
701 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 702 | struct list_head *list; |
e5d1367f SE |
703 | unsigned long flags; |
704 | ||
705 | /* | |
058fe1c0 DCC |
706 | * Disable interrupts and preemption to avoid this CPU's |
707 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
708 | */ |
709 | local_irq_save(flags); | |
710 | ||
058fe1c0 DCC |
711 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
712 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
713 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 714 | |
058fe1c0 DCC |
715 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
716 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 717 | |
058fe1c0 DCC |
718 | if (mode & PERF_CGROUP_SWOUT) { |
719 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
720 | /* | |
721 | * must not be done before ctxswout due | |
722 | * to event_filter_match() in event_sched_out() | |
723 | */ | |
724 | cpuctx->cgrp = NULL; | |
725 | } | |
e5d1367f | 726 | |
058fe1c0 DCC |
727 | if (mode & PERF_CGROUP_SWIN) { |
728 | WARN_ON_ONCE(cpuctx->cgrp); | |
729 | /* | |
730 | * set cgrp before ctxsw in to allow | |
731 | * event_filter_match() to not have to pass | |
732 | * task around | |
733 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
734 | * because cgorup events are only per-cpu | |
735 | */ | |
736 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
737 | &cpuctx->ctx); | |
738 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 739 | } |
058fe1c0 DCC |
740 | perf_pmu_enable(cpuctx->ctx.pmu); |
741 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
742 | } |
743 | ||
e5d1367f SE |
744 | local_irq_restore(flags); |
745 | } | |
746 | ||
a8d757ef SE |
747 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
748 | struct task_struct *next) | |
e5d1367f | 749 | { |
a8d757ef SE |
750 | struct perf_cgroup *cgrp1; |
751 | struct perf_cgroup *cgrp2 = NULL; | |
752 | ||
ddaaf4e2 | 753 | rcu_read_lock(); |
a8d757ef SE |
754 | /* |
755 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
756 | * we do not need to pass the ctx here because we know |
757 | * we are holding the rcu lock | |
a8d757ef | 758 | */ |
614e4c4e | 759 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 760 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
761 | |
762 | /* | |
763 | * only schedule out current cgroup events if we know | |
764 | * that we are switching to a different cgroup. Otherwise, | |
765 | * do no touch the cgroup events. | |
766 | */ | |
767 | if (cgrp1 != cgrp2) | |
768 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
769 | |
770 | rcu_read_unlock(); | |
e5d1367f SE |
771 | } |
772 | ||
a8d757ef SE |
773 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
774 | struct task_struct *task) | |
e5d1367f | 775 | { |
a8d757ef SE |
776 | struct perf_cgroup *cgrp1; |
777 | struct perf_cgroup *cgrp2 = NULL; | |
778 | ||
ddaaf4e2 | 779 | rcu_read_lock(); |
a8d757ef SE |
780 | /* |
781 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
782 | * we do not need to pass the ctx here because we know |
783 | * we are holding the rcu lock | |
a8d757ef | 784 | */ |
614e4c4e | 785 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 786 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
787 | |
788 | /* | |
789 | * only need to schedule in cgroup events if we are changing | |
790 | * cgroup during ctxsw. Cgroup events were not scheduled | |
791 | * out of ctxsw out if that was not the case. | |
792 | */ | |
793 | if (cgrp1 != cgrp2) | |
794 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
795 | |
796 | rcu_read_unlock(); | |
e5d1367f SE |
797 | } |
798 | ||
799 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
800 | struct perf_event_attr *attr, | |
801 | struct perf_event *group_leader) | |
802 | { | |
803 | struct perf_cgroup *cgrp; | |
804 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
805 | struct fd f = fdget(fd); |
806 | int ret = 0; | |
e5d1367f | 807 | |
2903ff01 | 808 | if (!f.file) |
e5d1367f SE |
809 | return -EBADF; |
810 | ||
b583043e | 811 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 812 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
813 | if (IS_ERR(css)) { |
814 | ret = PTR_ERR(css); | |
815 | goto out; | |
816 | } | |
e5d1367f SE |
817 | |
818 | cgrp = container_of(css, struct perf_cgroup, css); | |
819 | event->cgrp = cgrp; | |
820 | ||
821 | /* | |
822 | * all events in a group must monitor | |
823 | * the same cgroup because a task belongs | |
824 | * to only one perf cgroup at a time | |
825 | */ | |
826 | if (group_leader && group_leader->cgrp != cgrp) { | |
827 | perf_detach_cgroup(event); | |
828 | ret = -EINVAL; | |
e5d1367f | 829 | } |
3db272c0 | 830 | out: |
2903ff01 | 831 | fdput(f); |
e5d1367f SE |
832 | return ret; |
833 | } | |
834 | ||
835 | static inline void | |
836 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
837 | { | |
838 | struct perf_cgroup_info *t; | |
839 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
840 | event->shadow_ctx_time = now - t->timestamp; | |
841 | } | |
842 | ||
843 | static inline void | |
844 | perf_cgroup_defer_enabled(struct perf_event *event) | |
845 | { | |
846 | /* | |
847 | * when the current task's perf cgroup does not match | |
848 | * the event's, we need to remember to call the | |
849 | * perf_mark_enable() function the first time a task with | |
850 | * a matching perf cgroup is scheduled in. | |
851 | */ | |
852 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
853 | event->cgrp_defer_enabled = 1; | |
854 | } | |
855 | ||
856 | static inline void | |
857 | perf_cgroup_mark_enabled(struct perf_event *event, | |
858 | struct perf_event_context *ctx) | |
859 | { | |
860 | struct perf_event *sub; | |
861 | u64 tstamp = perf_event_time(event); | |
862 | ||
863 | if (!event->cgrp_defer_enabled) | |
864 | return; | |
865 | ||
866 | event->cgrp_defer_enabled = 0; | |
867 | ||
868 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
869 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
870 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
871 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
872 | sub->cgrp_defer_enabled = 0; | |
873 | } | |
874 | } | |
875 | } | |
db4a8356 DCC |
876 | |
877 | /* | |
878 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
879 | * cleared when last cgroup event is removed. | |
880 | */ | |
881 | static inline void | |
882 | list_update_cgroup_event(struct perf_event *event, | |
883 | struct perf_event_context *ctx, bool add) | |
884 | { | |
885 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 886 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
887 | |
888 | if (!is_cgroup_event(event)) | |
889 | return; | |
890 | ||
891 | if (add && ctx->nr_cgroups++) | |
892 | return; | |
893 | else if (!add && --ctx->nr_cgroups) | |
894 | return; | |
895 | /* | |
896 | * Because cgroup events are always per-cpu events, | |
897 | * this will always be called from the right CPU. | |
898 | */ | |
899 | cpuctx = __get_cpu_context(ctx); | |
058fe1c0 DCC |
900 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; |
901 | /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/ | |
902 | if (add) { | |
903 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
904 | if (perf_cgroup_from_task(current, ctx) == event->cgrp) | |
905 | cpuctx->cgrp = event->cgrp; | |
906 | } else { | |
907 | list_del(cpuctx_entry); | |
8fc31ce8 | 908 | cpuctx->cgrp = NULL; |
058fe1c0 | 909 | } |
db4a8356 DCC |
910 | } |
911 | ||
e5d1367f SE |
912 | #else /* !CONFIG_CGROUP_PERF */ |
913 | ||
914 | static inline bool | |
915 | perf_cgroup_match(struct perf_event *event) | |
916 | { | |
917 | return true; | |
918 | } | |
919 | ||
920 | static inline void perf_detach_cgroup(struct perf_event *event) | |
921 | {} | |
922 | ||
923 | static inline int is_cgroup_event(struct perf_event *event) | |
924 | { | |
925 | return 0; | |
926 | } | |
927 | ||
928 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
929 | { | |
930 | return 0; | |
931 | } | |
932 | ||
933 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
934 | { | |
935 | } | |
936 | ||
937 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
938 | { | |
939 | } | |
940 | ||
a8d757ef SE |
941 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
942 | struct task_struct *next) | |
e5d1367f SE |
943 | { |
944 | } | |
945 | ||
a8d757ef SE |
946 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
947 | struct task_struct *task) | |
e5d1367f SE |
948 | { |
949 | } | |
950 | ||
951 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
952 | struct perf_event_attr *attr, | |
953 | struct perf_event *group_leader) | |
954 | { | |
955 | return -EINVAL; | |
956 | } | |
957 | ||
958 | static inline void | |
3f7cce3c SE |
959 | perf_cgroup_set_timestamp(struct task_struct *task, |
960 | struct perf_event_context *ctx) | |
e5d1367f SE |
961 | { |
962 | } | |
963 | ||
964 | void | |
965 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
966 | { | |
967 | } | |
968 | ||
969 | static inline void | |
970 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
971 | { | |
972 | } | |
973 | ||
974 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
975 | { | |
976 | return 0; | |
977 | } | |
978 | ||
979 | static inline void | |
980 | perf_cgroup_defer_enabled(struct perf_event *event) | |
981 | { | |
982 | } | |
983 | ||
984 | static inline void | |
985 | perf_cgroup_mark_enabled(struct perf_event *event, | |
986 | struct perf_event_context *ctx) | |
987 | { | |
988 | } | |
db4a8356 DCC |
989 | |
990 | static inline void | |
991 | list_update_cgroup_event(struct perf_event *event, | |
992 | struct perf_event_context *ctx, bool add) | |
993 | { | |
994 | } | |
995 | ||
e5d1367f SE |
996 | #endif |
997 | ||
9e630205 SE |
998 | /* |
999 | * set default to be dependent on timer tick just | |
1000 | * like original code | |
1001 | */ | |
1002 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1003 | /* | |
8a1115ff | 1004 | * function must be called with interrupts disabled |
9e630205 | 1005 | */ |
272325c4 | 1006 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1007 | { |
1008 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1009 | int rotations = 0; |
1010 | ||
1011 | WARN_ON(!irqs_disabled()); | |
1012 | ||
1013 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1014 | rotations = perf_rotate_context(cpuctx); |
1015 | ||
4cfafd30 PZ |
1016 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1017 | if (rotations) | |
9e630205 | 1018 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1019 | else |
1020 | cpuctx->hrtimer_active = 0; | |
1021 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1022 | |
4cfafd30 | 1023 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1024 | } |
1025 | ||
272325c4 | 1026 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1027 | { |
272325c4 | 1028 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1029 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1030 | u64 interval; |
9e630205 SE |
1031 | |
1032 | /* no multiplexing needed for SW PMU */ | |
1033 | if (pmu->task_ctx_nr == perf_sw_context) | |
1034 | return; | |
1035 | ||
62b85639 SE |
1036 | /* |
1037 | * check default is sane, if not set then force to | |
1038 | * default interval (1/tick) | |
1039 | */ | |
272325c4 PZ |
1040 | interval = pmu->hrtimer_interval_ms; |
1041 | if (interval < 1) | |
1042 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1043 | |
272325c4 | 1044 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1045 | |
4cfafd30 PZ |
1046 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1047 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1048 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1049 | } |
1050 | ||
272325c4 | 1051 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1052 | { |
272325c4 | 1053 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1054 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1055 | unsigned long flags; |
9e630205 SE |
1056 | |
1057 | /* not for SW PMU */ | |
1058 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1059 | return 0; |
9e630205 | 1060 | |
4cfafd30 PZ |
1061 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1062 | if (!cpuctx->hrtimer_active) { | |
1063 | cpuctx->hrtimer_active = 1; | |
1064 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1065 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1066 | } | |
1067 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1068 | |
272325c4 | 1069 | return 0; |
9e630205 SE |
1070 | } |
1071 | ||
33696fc0 | 1072 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1073 | { |
33696fc0 PZ |
1074 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1075 | if (!(*count)++) | |
1076 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1077 | } |
9e35ad38 | 1078 | |
33696fc0 | 1079 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1080 | { |
33696fc0 PZ |
1081 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1082 | if (!--(*count)) | |
1083 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1084 | } |
9e35ad38 | 1085 | |
2fde4f94 | 1086 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1087 | |
1088 | /* | |
2fde4f94 MR |
1089 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1090 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1091 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1092 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1093 | */ |
2fde4f94 | 1094 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1095 | { |
2fde4f94 | 1096 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1097 | |
e9d2b064 | 1098 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1099 | |
2fde4f94 MR |
1100 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1101 | ||
1102 | list_add(&ctx->active_ctx_list, head); | |
1103 | } | |
1104 | ||
1105 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1106 | { | |
1107 | WARN_ON(!irqs_disabled()); | |
1108 | ||
1109 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1110 | ||
1111 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1112 | } |
9e35ad38 | 1113 | |
cdd6c482 | 1114 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1115 | { |
e5289d4a | 1116 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1117 | } |
1118 | ||
4af57ef2 YZ |
1119 | static void free_ctx(struct rcu_head *head) |
1120 | { | |
1121 | struct perf_event_context *ctx; | |
1122 | ||
1123 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1124 | kfree(ctx->task_ctx_data); | |
1125 | kfree(ctx); | |
1126 | } | |
1127 | ||
cdd6c482 | 1128 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1129 | { |
564c2b21 PM |
1130 | if (atomic_dec_and_test(&ctx->refcount)) { |
1131 | if (ctx->parent_ctx) | |
1132 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1133 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1134 | put_task_struct(ctx->task); |
4af57ef2 | 1135 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1136 | } |
a63eaf34 PM |
1137 | } |
1138 | ||
f63a8daa PZ |
1139 | /* |
1140 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1141 | * perf_pmu_migrate_context() we need some magic. | |
1142 | * | |
1143 | * Those places that change perf_event::ctx will hold both | |
1144 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1145 | * | |
8b10c5e2 PZ |
1146 | * Lock ordering is by mutex address. There are two other sites where |
1147 | * perf_event_context::mutex nests and those are: | |
1148 | * | |
1149 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1150 | * perf_event_exit_event() |
1151 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1152 | * |
1153 | * - perf_event_init_context() [ parent, 0 ] | |
1154 | * inherit_task_group() | |
1155 | * inherit_group() | |
1156 | * inherit_event() | |
1157 | * perf_event_alloc() | |
1158 | * perf_init_event() | |
1159 | * perf_try_init_event() [ child , 1 ] | |
1160 | * | |
1161 | * While it appears there is an obvious deadlock here -- the parent and child | |
1162 | * nesting levels are inverted between the two. This is in fact safe because | |
1163 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1164 | * spawning task cannot (yet) exit. | |
1165 | * | |
1166 | * But remember that that these are parent<->child context relations, and | |
1167 | * migration does not affect children, therefore these two orderings should not | |
1168 | * interact. | |
f63a8daa PZ |
1169 | * |
1170 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1171 | * because the sys_perf_event_open() case will install a new event and break | |
1172 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1173 | * concerned with cpuctx and that doesn't have children. | |
1174 | * | |
1175 | * The places that change perf_event::ctx will issue: | |
1176 | * | |
1177 | * perf_remove_from_context(); | |
1178 | * synchronize_rcu(); | |
1179 | * perf_install_in_context(); | |
1180 | * | |
1181 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1182 | * quiesce the event, after which we can install it in the new location. This | |
1183 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1184 | * while in transit. Therefore all such accessors should also acquire | |
1185 | * perf_event_context::mutex to serialize against this. | |
1186 | * | |
1187 | * However; because event->ctx can change while we're waiting to acquire | |
1188 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1189 | * function. | |
1190 | * | |
1191 | * Lock order: | |
79c9ce57 | 1192 | * cred_guard_mutex |
f63a8daa PZ |
1193 | * task_struct::perf_event_mutex |
1194 | * perf_event_context::mutex | |
f63a8daa | 1195 | * perf_event::child_mutex; |
07c4a776 | 1196 | * perf_event_context::lock |
f63a8daa PZ |
1197 | * perf_event::mmap_mutex |
1198 | * mmap_sem | |
1199 | */ | |
a83fe28e PZ |
1200 | static struct perf_event_context * |
1201 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1202 | { |
1203 | struct perf_event_context *ctx; | |
1204 | ||
1205 | again: | |
1206 | rcu_read_lock(); | |
1207 | ctx = ACCESS_ONCE(event->ctx); | |
1208 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1209 | rcu_read_unlock(); | |
1210 | goto again; | |
1211 | } | |
1212 | rcu_read_unlock(); | |
1213 | ||
a83fe28e | 1214 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1215 | if (event->ctx != ctx) { |
1216 | mutex_unlock(&ctx->mutex); | |
1217 | put_ctx(ctx); | |
1218 | goto again; | |
1219 | } | |
1220 | ||
1221 | return ctx; | |
1222 | } | |
1223 | ||
a83fe28e PZ |
1224 | static inline struct perf_event_context * |
1225 | perf_event_ctx_lock(struct perf_event *event) | |
1226 | { | |
1227 | return perf_event_ctx_lock_nested(event, 0); | |
1228 | } | |
1229 | ||
f63a8daa PZ |
1230 | static void perf_event_ctx_unlock(struct perf_event *event, |
1231 | struct perf_event_context *ctx) | |
1232 | { | |
1233 | mutex_unlock(&ctx->mutex); | |
1234 | put_ctx(ctx); | |
1235 | } | |
1236 | ||
211de6eb PZ |
1237 | /* |
1238 | * This must be done under the ctx->lock, such as to serialize against | |
1239 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1240 | * calling scheduler related locks and ctx->lock nests inside those. | |
1241 | */ | |
1242 | static __must_check struct perf_event_context * | |
1243 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1244 | { |
211de6eb PZ |
1245 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1246 | ||
1247 | lockdep_assert_held(&ctx->lock); | |
1248 | ||
1249 | if (parent_ctx) | |
71a851b4 | 1250 | ctx->parent_ctx = NULL; |
5a3126d4 | 1251 | ctx->generation++; |
211de6eb PZ |
1252 | |
1253 | return parent_ctx; | |
71a851b4 PZ |
1254 | } |
1255 | ||
6844c09d ACM |
1256 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1257 | { | |
1258 | /* | |
1259 | * only top level events have the pid namespace they were created in | |
1260 | */ | |
1261 | if (event->parent) | |
1262 | event = event->parent; | |
1263 | ||
1264 | return task_tgid_nr_ns(p, event->ns); | |
1265 | } | |
1266 | ||
1267 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1268 | { | |
1269 | /* | |
1270 | * only top level events have the pid namespace they were created in | |
1271 | */ | |
1272 | if (event->parent) | |
1273 | event = event->parent; | |
1274 | ||
1275 | return task_pid_nr_ns(p, event->ns); | |
1276 | } | |
1277 | ||
7f453c24 | 1278 | /* |
cdd6c482 | 1279 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1280 | * to userspace. |
1281 | */ | |
cdd6c482 | 1282 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1283 | { |
cdd6c482 | 1284 | u64 id = event->id; |
7f453c24 | 1285 | |
cdd6c482 IM |
1286 | if (event->parent) |
1287 | id = event->parent->id; | |
7f453c24 PZ |
1288 | |
1289 | return id; | |
1290 | } | |
1291 | ||
25346b93 | 1292 | /* |
cdd6c482 | 1293 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1294 | * |
25346b93 PM |
1295 | * This has to cope with with the fact that until it is locked, |
1296 | * the context could get moved to another task. | |
1297 | */ | |
cdd6c482 | 1298 | static struct perf_event_context * |
8dc85d54 | 1299 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1300 | { |
cdd6c482 | 1301 | struct perf_event_context *ctx; |
25346b93 | 1302 | |
9ed6060d | 1303 | retry: |
058ebd0e PZ |
1304 | /* |
1305 | * One of the few rules of preemptible RCU is that one cannot do | |
1306 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1307 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1308 | * rcu_read_unlock_special(). |
1309 | * | |
1310 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1311 | * side critical section has interrupts disabled. |
058ebd0e | 1312 | */ |
2fd59077 | 1313 | local_irq_save(*flags); |
058ebd0e | 1314 | rcu_read_lock(); |
8dc85d54 | 1315 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1316 | if (ctx) { |
1317 | /* | |
1318 | * If this context is a clone of another, it might | |
1319 | * get swapped for another underneath us by | |
cdd6c482 | 1320 | * perf_event_task_sched_out, though the |
25346b93 PM |
1321 | * rcu_read_lock() protects us from any context |
1322 | * getting freed. Lock the context and check if it | |
1323 | * got swapped before we could get the lock, and retry | |
1324 | * if so. If we locked the right context, then it | |
1325 | * can't get swapped on us any more. | |
1326 | */ | |
2fd59077 | 1327 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1328 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1329 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1330 | rcu_read_unlock(); |
2fd59077 | 1331 | local_irq_restore(*flags); |
25346b93 PM |
1332 | goto retry; |
1333 | } | |
b49a9e7e | 1334 | |
63b6da39 PZ |
1335 | if (ctx->task == TASK_TOMBSTONE || |
1336 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1337 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1338 | ctx = NULL; |
828b6f0e PZ |
1339 | } else { |
1340 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1341 | } |
25346b93 PM |
1342 | } |
1343 | rcu_read_unlock(); | |
2fd59077 PM |
1344 | if (!ctx) |
1345 | local_irq_restore(*flags); | |
25346b93 PM |
1346 | return ctx; |
1347 | } | |
1348 | ||
1349 | /* | |
1350 | * Get the context for a task and increment its pin_count so it | |
1351 | * can't get swapped to another task. This also increments its | |
1352 | * reference count so that the context can't get freed. | |
1353 | */ | |
8dc85d54 PZ |
1354 | static struct perf_event_context * |
1355 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1356 | { |
cdd6c482 | 1357 | struct perf_event_context *ctx; |
25346b93 PM |
1358 | unsigned long flags; |
1359 | ||
8dc85d54 | 1360 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1361 | if (ctx) { |
1362 | ++ctx->pin_count; | |
e625cce1 | 1363 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1364 | } |
1365 | return ctx; | |
1366 | } | |
1367 | ||
cdd6c482 | 1368 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1369 | { |
1370 | unsigned long flags; | |
1371 | ||
e625cce1 | 1372 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1373 | --ctx->pin_count; |
e625cce1 | 1374 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1375 | } |
1376 | ||
f67218c3 PZ |
1377 | /* |
1378 | * Update the record of the current time in a context. | |
1379 | */ | |
1380 | static void update_context_time(struct perf_event_context *ctx) | |
1381 | { | |
1382 | u64 now = perf_clock(); | |
1383 | ||
1384 | ctx->time += now - ctx->timestamp; | |
1385 | ctx->timestamp = now; | |
1386 | } | |
1387 | ||
4158755d SE |
1388 | static u64 perf_event_time(struct perf_event *event) |
1389 | { | |
1390 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1391 | |
1392 | if (is_cgroup_event(event)) | |
1393 | return perf_cgroup_event_time(event); | |
1394 | ||
4158755d SE |
1395 | return ctx ? ctx->time : 0; |
1396 | } | |
1397 | ||
f67218c3 PZ |
1398 | /* |
1399 | * Update the total_time_enabled and total_time_running fields for a event. | |
1400 | */ | |
1401 | static void update_event_times(struct perf_event *event) | |
1402 | { | |
1403 | struct perf_event_context *ctx = event->ctx; | |
1404 | u64 run_end; | |
1405 | ||
3cbaa590 PZ |
1406 | lockdep_assert_held(&ctx->lock); |
1407 | ||
f67218c3 PZ |
1408 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1409 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1410 | return; | |
3cbaa590 | 1411 | |
e5d1367f SE |
1412 | /* |
1413 | * in cgroup mode, time_enabled represents | |
1414 | * the time the event was enabled AND active | |
1415 | * tasks were in the monitored cgroup. This is | |
1416 | * independent of the activity of the context as | |
1417 | * there may be a mix of cgroup and non-cgroup events. | |
1418 | * | |
1419 | * That is why we treat cgroup events differently | |
1420 | * here. | |
1421 | */ | |
1422 | if (is_cgroup_event(event)) | |
46cd6a7f | 1423 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1424 | else if (ctx->is_active) |
1425 | run_end = ctx->time; | |
acd1d7c1 PZ |
1426 | else |
1427 | run_end = event->tstamp_stopped; | |
1428 | ||
1429 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1430 | |
1431 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1432 | run_end = event->tstamp_stopped; | |
1433 | else | |
4158755d | 1434 | run_end = perf_event_time(event); |
f67218c3 PZ |
1435 | |
1436 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1437 | |
f67218c3 PZ |
1438 | } |
1439 | ||
96c21a46 PZ |
1440 | /* |
1441 | * Update total_time_enabled and total_time_running for all events in a group. | |
1442 | */ | |
1443 | static void update_group_times(struct perf_event *leader) | |
1444 | { | |
1445 | struct perf_event *event; | |
1446 | ||
1447 | update_event_times(leader); | |
1448 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1449 | update_event_times(event); | |
1450 | } | |
1451 | ||
487f05e1 AS |
1452 | static enum event_type_t get_event_type(struct perf_event *event) |
1453 | { | |
1454 | struct perf_event_context *ctx = event->ctx; | |
1455 | enum event_type_t event_type; | |
1456 | ||
1457 | lockdep_assert_held(&ctx->lock); | |
1458 | ||
1459 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; | |
1460 | if (!ctx->task) | |
1461 | event_type |= EVENT_CPU; | |
1462 | ||
1463 | return event_type; | |
1464 | } | |
1465 | ||
889ff015 FW |
1466 | static struct list_head * |
1467 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1468 | { | |
1469 | if (event->attr.pinned) | |
1470 | return &ctx->pinned_groups; | |
1471 | else | |
1472 | return &ctx->flexible_groups; | |
1473 | } | |
1474 | ||
fccc714b | 1475 | /* |
cdd6c482 | 1476 | * Add a event from the lists for its context. |
fccc714b PZ |
1477 | * Must be called with ctx->mutex and ctx->lock held. |
1478 | */ | |
04289bb9 | 1479 | static void |
cdd6c482 | 1480 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1481 | { |
c994d613 PZ |
1482 | lockdep_assert_held(&ctx->lock); |
1483 | ||
8a49542c PZ |
1484 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1485 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1486 | |
1487 | /* | |
8a49542c PZ |
1488 | * If we're a stand alone event or group leader, we go to the context |
1489 | * list, group events are kept attached to the group so that | |
1490 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1491 | */ |
8a49542c | 1492 | if (event->group_leader == event) { |
889ff015 FW |
1493 | struct list_head *list; |
1494 | ||
4ff6a8de | 1495 | event->group_caps = event->event_caps; |
d6f962b5 | 1496 | |
889ff015 FW |
1497 | list = ctx_group_list(event, ctx); |
1498 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1499 | } |
592903cd | 1500 | |
db4a8356 | 1501 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1502 | |
cdd6c482 IM |
1503 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1504 | ctx->nr_events++; | |
1505 | if (event->attr.inherit_stat) | |
bfbd3381 | 1506 | ctx->nr_stat++; |
5a3126d4 PZ |
1507 | |
1508 | ctx->generation++; | |
04289bb9 IM |
1509 | } |
1510 | ||
0231bb53 JO |
1511 | /* |
1512 | * Initialize event state based on the perf_event_attr::disabled. | |
1513 | */ | |
1514 | static inline void perf_event__state_init(struct perf_event *event) | |
1515 | { | |
1516 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1517 | PERF_EVENT_STATE_INACTIVE; | |
1518 | } | |
1519 | ||
a723968c | 1520 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1521 | { |
1522 | int entry = sizeof(u64); /* value */ | |
1523 | int size = 0; | |
1524 | int nr = 1; | |
1525 | ||
1526 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1527 | size += sizeof(u64); | |
1528 | ||
1529 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1530 | size += sizeof(u64); | |
1531 | ||
1532 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1533 | entry += sizeof(u64); | |
1534 | ||
1535 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1536 | nr += nr_siblings; |
c320c7b7 ACM |
1537 | size += sizeof(u64); |
1538 | } | |
1539 | ||
1540 | size += entry * nr; | |
1541 | event->read_size = size; | |
1542 | } | |
1543 | ||
a723968c | 1544 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1545 | { |
1546 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1547 | u16 size = 0; |
1548 | ||
c320c7b7 ACM |
1549 | if (sample_type & PERF_SAMPLE_IP) |
1550 | size += sizeof(data->ip); | |
1551 | ||
6844c09d ACM |
1552 | if (sample_type & PERF_SAMPLE_ADDR) |
1553 | size += sizeof(data->addr); | |
1554 | ||
1555 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1556 | size += sizeof(data->period); | |
1557 | ||
c3feedf2 AK |
1558 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1559 | size += sizeof(data->weight); | |
1560 | ||
6844c09d ACM |
1561 | if (sample_type & PERF_SAMPLE_READ) |
1562 | size += event->read_size; | |
1563 | ||
d6be9ad6 SE |
1564 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1565 | size += sizeof(data->data_src.val); | |
1566 | ||
fdfbbd07 AK |
1567 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1568 | size += sizeof(data->txn); | |
1569 | ||
6844c09d ACM |
1570 | event->header_size = size; |
1571 | } | |
1572 | ||
a723968c PZ |
1573 | /* |
1574 | * Called at perf_event creation and when events are attached/detached from a | |
1575 | * group. | |
1576 | */ | |
1577 | static void perf_event__header_size(struct perf_event *event) | |
1578 | { | |
1579 | __perf_event_read_size(event, | |
1580 | event->group_leader->nr_siblings); | |
1581 | __perf_event_header_size(event, event->attr.sample_type); | |
1582 | } | |
1583 | ||
6844c09d ACM |
1584 | static void perf_event__id_header_size(struct perf_event *event) |
1585 | { | |
1586 | struct perf_sample_data *data; | |
1587 | u64 sample_type = event->attr.sample_type; | |
1588 | u16 size = 0; | |
1589 | ||
c320c7b7 ACM |
1590 | if (sample_type & PERF_SAMPLE_TID) |
1591 | size += sizeof(data->tid_entry); | |
1592 | ||
1593 | if (sample_type & PERF_SAMPLE_TIME) | |
1594 | size += sizeof(data->time); | |
1595 | ||
ff3d527c AH |
1596 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1597 | size += sizeof(data->id); | |
1598 | ||
c320c7b7 ACM |
1599 | if (sample_type & PERF_SAMPLE_ID) |
1600 | size += sizeof(data->id); | |
1601 | ||
1602 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1603 | size += sizeof(data->stream_id); | |
1604 | ||
1605 | if (sample_type & PERF_SAMPLE_CPU) | |
1606 | size += sizeof(data->cpu_entry); | |
1607 | ||
6844c09d | 1608 | event->id_header_size = size; |
c320c7b7 ACM |
1609 | } |
1610 | ||
a723968c PZ |
1611 | static bool perf_event_validate_size(struct perf_event *event) |
1612 | { | |
1613 | /* | |
1614 | * The values computed here will be over-written when we actually | |
1615 | * attach the event. | |
1616 | */ | |
1617 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1618 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1619 | perf_event__id_header_size(event); | |
1620 | ||
1621 | /* | |
1622 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1623 | * Conservative limit to allow for callchains and other variable fields. | |
1624 | */ | |
1625 | if (event->read_size + event->header_size + | |
1626 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1627 | return false; | |
1628 | ||
1629 | return true; | |
1630 | } | |
1631 | ||
8a49542c PZ |
1632 | static void perf_group_attach(struct perf_event *event) |
1633 | { | |
c320c7b7 | 1634 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1635 | |
a76a82a3 PZ |
1636 | lockdep_assert_held(&event->ctx->lock); |
1637 | ||
74c3337c PZ |
1638 | /* |
1639 | * We can have double attach due to group movement in perf_event_open. | |
1640 | */ | |
1641 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1642 | return; | |
1643 | ||
8a49542c PZ |
1644 | event->attach_state |= PERF_ATTACH_GROUP; |
1645 | ||
1646 | if (group_leader == event) | |
1647 | return; | |
1648 | ||
652884fe PZ |
1649 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1650 | ||
4ff6a8de | 1651 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1652 | |
1653 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1654 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1655 | |
1656 | perf_event__header_size(group_leader); | |
1657 | ||
1658 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1659 | perf_event__header_size(pos); | |
8a49542c PZ |
1660 | } |
1661 | ||
a63eaf34 | 1662 | /* |
cdd6c482 | 1663 | * Remove a event from the lists for its context. |
fccc714b | 1664 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1665 | */ |
04289bb9 | 1666 | static void |
cdd6c482 | 1667 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1668 | { |
652884fe PZ |
1669 | WARN_ON_ONCE(event->ctx != ctx); |
1670 | lockdep_assert_held(&ctx->lock); | |
1671 | ||
8a49542c PZ |
1672 | /* |
1673 | * We can have double detach due to exit/hot-unplug + close. | |
1674 | */ | |
1675 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1676 | return; |
8a49542c PZ |
1677 | |
1678 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1679 | ||
db4a8356 | 1680 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1681 | |
cdd6c482 IM |
1682 | ctx->nr_events--; |
1683 | if (event->attr.inherit_stat) | |
bfbd3381 | 1684 | ctx->nr_stat--; |
8bc20959 | 1685 | |
cdd6c482 | 1686 | list_del_rcu(&event->event_entry); |
04289bb9 | 1687 | |
8a49542c PZ |
1688 | if (event->group_leader == event) |
1689 | list_del_init(&event->group_entry); | |
5c148194 | 1690 | |
96c21a46 | 1691 | update_group_times(event); |
b2e74a26 SE |
1692 | |
1693 | /* | |
1694 | * If event was in error state, then keep it | |
1695 | * that way, otherwise bogus counts will be | |
1696 | * returned on read(). The only way to get out | |
1697 | * of error state is by explicit re-enabling | |
1698 | * of the event | |
1699 | */ | |
1700 | if (event->state > PERF_EVENT_STATE_OFF) | |
1701 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1702 | |
1703 | ctx->generation++; | |
050735b0 PZ |
1704 | } |
1705 | ||
8a49542c | 1706 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1707 | { |
1708 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1709 | struct list_head *list = NULL; |
1710 | ||
a76a82a3 PZ |
1711 | lockdep_assert_held(&event->ctx->lock); |
1712 | ||
8a49542c PZ |
1713 | /* |
1714 | * We can have double detach due to exit/hot-unplug + close. | |
1715 | */ | |
1716 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1717 | return; | |
1718 | ||
1719 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1720 | ||
1721 | /* | |
1722 | * If this is a sibling, remove it from its group. | |
1723 | */ | |
1724 | if (event->group_leader != event) { | |
1725 | list_del_init(&event->group_entry); | |
1726 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1727 | goto out; |
8a49542c PZ |
1728 | } |
1729 | ||
1730 | if (!list_empty(&event->group_entry)) | |
1731 | list = &event->group_entry; | |
2e2af50b | 1732 | |
04289bb9 | 1733 | /* |
cdd6c482 IM |
1734 | * If this was a group event with sibling events then |
1735 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1736 | * to whatever list we are on. |
04289bb9 | 1737 | */ |
cdd6c482 | 1738 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1739 | if (list) |
1740 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1741 | sibling->group_leader = sibling; |
d6f962b5 FW |
1742 | |
1743 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1744 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1745 | |
1746 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1747 | } |
c320c7b7 ACM |
1748 | |
1749 | out: | |
1750 | perf_event__header_size(event->group_leader); | |
1751 | ||
1752 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1753 | perf_event__header_size(tmp); | |
04289bb9 IM |
1754 | } |
1755 | ||
fadfe7be JO |
1756 | static bool is_orphaned_event(struct perf_event *event) |
1757 | { | |
a69b0ca4 | 1758 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1759 | } |
1760 | ||
2c81a647 | 1761 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1762 | { |
1763 | struct pmu *pmu = event->pmu; | |
1764 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1765 | } | |
1766 | ||
2c81a647 MR |
1767 | /* |
1768 | * Check whether we should attempt to schedule an event group based on | |
1769 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1770 | * potentially with a SW leader, so we must check all the filters, to | |
1771 | * determine whether a group is schedulable: | |
1772 | */ | |
1773 | static inline int pmu_filter_match(struct perf_event *event) | |
1774 | { | |
1775 | struct perf_event *child; | |
1776 | ||
1777 | if (!__pmu_filter_match(event)) | |
1778 | return 0; | |
1779 | ||
1780 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1781 | if (!__pmu_filter_match(child)) | |
1782 | return 0; | |
1783 | } | |
1784 | ||
1785 | return 1; | |
1786 | } | |
1787 | ||
fa66f07a SE |
1788 | static inline int |
1789 | event_filter_match(struct perf_event *event) | |
1790 | { | |
0b8f1e2e PZ |
1791 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1792 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1793 | } |
1794 | ||
9ffcfa6f SE |
1795 | static void |
1796 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1797 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1798 | struct perf_event_context *ctx) |
3b6f9e5c | 1799 | { |
4158755d | 1800 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1801 | u64 delta; |
652884fe PZ |
1802 | |
1803 | WARN_ON_ONCE(event->ctx != ctx); | |
1804 | lockdep_assert_held(&ctx->lock); | |
1805 | ||
fa66f07a SE |
1806 | /* |
1807 | * An event which could not be activated because of | |
1808 | * filter mismatch still needs to have its timings | |
1809 | * maintained, otherwise bogus information is return | |
1810 | * via read() for time_enabled, time_running: | |
1811 | */ | |
0b8f1e2e PZ |
1812 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1813 | !event_filter_match(event)) { | |
e5d1367f | 1814 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1815 | event->tstamp_running += delta; |
4158755d | 1816 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1817 | } |
1818 | ||
cdd6c482 | 1819 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1820 | return; |
3b6f9e5c | 1821 | |
44377277 AS |
1822 | perf_pmu_disable(event->pmu); |
1823 | ||
28a967c3 PZ |
1824 | event->tstamp_stopped = tstamp; |
1825 | event->pmu->del(event, 0); | |
1826 | event->oncpu = -1; | |
cdd6c482 IM |
1827 | event->state = PERF_EVENT_STATE_INACTIVE; |
1828 | if (event->pending_disable) { | |
1829 | event->pending_disable = 0; | |
1830 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1831 | } |
3b6f9e5c | 1832 | |
cdd6c482 | 1833 | if (!is_software_event(event)) |
3b6f9e5c | 1834 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1835 | if (!--ctx->nr_active) |
1836 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1837 | if (event->attr.freq && event->attr.sample_freq) |
1838 | ctx->nr_freq--; | |
cdd6c482 | 1839 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1840 | cpuctx->exclusive = 0; |
44377277 AS |
1841 | |
1842 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1843 | } |
1844 | ||
d859e29f | 1845 | static void |
cdd6c482 | 1846 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1847 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1848 | struct perf_event_context *ctx) |
d859e29f | 1849 | { |
cdd6c482 | 1850 | struct perf_event *event; |
fa66f07a | 1851 | int state = group_event->state; |
d859e29f | 1852 | |
3f005e7d MR |
1853 | perf_pmu_disable(ctx->pmu); |
1854 | ||
cdd6c482 | 1855 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1856 | |
1857 | /* | |
1858 | * Schedule out siblings (if any): | |
1859 | */ | |
cdd6c482 IM |
1860 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1861 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1862 | |
3f005e7d MR |
1863 | perf_pmu_enable(ctx->pmu); |
1864 | ||
fa66f07a | 1865 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1866 | cpuctx->exclusive = 0; |
1867 | } | |
1868 | ||
45a0e07a | 1869 | #define DETACH_GROUP 0x01UL |
0017960f | 1870 | |
0793a61d | 1871 | /* |
cdd6c482 | 1872 | * Cross CPU call to remove a performance event |
0793a61d | 1873 | * |
cdd6c482 | 1874 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1875 | * remove it from the context list. |
1876 | */ | |
fae3fde6 PZ |
1877 | static void |
1878 | __perf_remove_from_context(struct perf_event *event, | |
1879 | struct perf_cpu_context *cpuctx, | |
1880 | struct perf_event_context *ctx, | |
1881 | void *info) | |
0793a61d | 1882 | { |
45a0e07a | 1883 | unsigned long flags = (unsigned long)info; |
0793a61d | 1884 | |
cdd6c482 | 1885 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1886 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1887 | perf_group_detach(event); |
cdd6c482 | 1888 | list_del_event(event, ctx); |
39a43640 PZ |
1889 | |
1890 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1891 | ctx->is_active = 0; |
39a43640 PZ |
1892 | if (ctx->task) { |
1893 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1894 | cpuctx->task_ctx = NULL; | |
1895 | } | |
64ce3126 | 1896 | } |
0793a61d TG |
1897 | } |
1898 | ||
0793a61d | 1899 | /* |
cdd6c482 | 1900 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1901 | * |
cdd6c482 IM |
1902 | * If event->ctx is a cloned context, callers must make sure that |
1903 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1904 | * remains valid. This is OK when called from perf_release since |
1905 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1906 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1907 | * context has been detached from its task. |
0793a61d | 1908 | */ |
45a0e07a | 1909 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1910 | { |
a76a82a3 PZ |
1911 | struct perf_event_context *ctx = event->ctx; |
1912 | ||
1913 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 1914 | |
45a0e07a | 1915 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
1916 | |
1917 | /* | |
1918 | * The above event_function_call() can NO-OP when it hits | |
1919 | * TASK_TOMBSTONE. In that case we must already have been detached | |
1920 | * from the context (by perf_event_exit_event()) but the grouping | |
1921 | * might still be in-tact. | |
1922 | */ | |
1923 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
1924 | if ((flags & DETACH_GROUP) && | |
1925 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
1926 | /* | |
1927 | * Since in that case we cannot possibly be scheduled, simply | |
1928 | * detach now. | |
1929 | */ | |
1930 | raw_spin_lock_irq(&ctx->lock); | |
1931 | perf_group_detach(event); | |
1932 | raw_spin_unlock_irq(&ctx->lock); | |
1933 | } | |
0793a61d TG |
1934 | } |
1935 | ||
d859e29f | 1936 | /* |
cdd6c482 | 1937 | * Cross CPU call to disable a performance event |
d859e29f | 1938 | */ |
fae3fde6 PZ |
1939 | static void __perf_event_disable(struct perf_event *event, |
1940 | struct perf_cpu_context *cpuctx, | |
1941 | struct perf_event_context *ctx, | |
1942 | void *info) | |
7b648018 | 1943 | { |
fae3fde6 PZ |
1944 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1945 | return; | |
7b648018 | 1946 | |
fae3fde6 PZ |
1947 | update_context_time(ctx); |
1948 | update_cgrp_time_from_event(event); | |
1949 | update_group_times(event); | |
1950 | if (event == event->group_leader) | |
1951 | group_sched_out(event, cpuctx, ctx); | |
1952 | else | |
1953 | event_sched_out(event, cpuctx, ctx); | |
1954 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1955 | } |
1956 | ||
d859e29f | 1957 | /* |
cdd6c482 | 1958 | * Disable a event. |
c93f7669 | 1959 | * |
cdd6c482 IM |
1960 | * If event->ctx is a cloned context, callers must make sure that |
1961 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1962 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1963 | * perf_event_for_each_child or perf_event_for_each because they |
1964 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1965 | * goes to exit will block in perf_event_exit_event(). |
1966 | * | |
cdd6c482 | 1967 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1968 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1969 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1970 | */ |
f63a8daa | 1971 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1972 | { |
cdd6c482 | 1973 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1974 | |
e625cce1 | 1975 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1976 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1977 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1978 | return; |
53cfbf59 | 1979 | } |
e625cce1 | 1980 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1981 | |
fae3fde6 PZ |
1982 | event_function_call(event, __perf_event_disable, NULL); |
1983 | } | |
1984 | ||
1985 | void perf_event_disable_local(struct perf_event *event) | |
1986 | { | |
1987 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1988 | } |
f63a8daa PZ |
1989 | |
1990 | /* | |
1991 | * Strictly speaking kernel users cannot create groups and therefore this | |
1992 | * interface does not need the perf_event_ctx_lock() magic. | |
1993 | */ | |
1994 | void perf_event_disable(struct perf_event *event) | |
1995 | { | |
1996 | struct perf_event_context *ctx; | |
1997 | ||
1998 | ctx = perf_event_ctx_lock(event); | |
1999 | _perf_event_disable(event); | |
2000 | perf_event_ctx_unlock(event, ctx); | |
2001 | } | |
dcfce4a0 | 2002 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2003 | |
5aab90ce JO |
2004 | void perf_event_disable_inatomic(struct perf_event *event) |
2005 | { | |
2006 | event->pending_disable = 1; | |
2007 | irq_work_queue(&event->pending); | |
2008 | } | |
2009 | ||
e5d1367f SE |
2010 | static void perf_set_shadow_time(struct perf_event *event, |
2011 | struct perf_event_context *ctx, | |
2012 | u64 tstamp) | |
2013 | { | |
2014 | /* | |
2015 | * use the correct time source for the time snapshot | |
2016 | * | |
2017 | * We could get by without this by leveraging the | |
2018 | * fact that to get to this function, the caller | |
2019 | * has most likely already called update_context_time() | |
2020 | * and update_cgrp_time_xx() and thus both timestamp | |
2021 | * are identical (or very close). Given that tstamp is, | |
2022 | * already adjusted for cgroup, we could say that: | |
2023 | * tstamp - ctx->timestamp | |
2024 | * is equivalent to | |
2025 | * tstamp - cgrp->timestamp. | |
2026 | * | |
2027 | * Then, in perf_output_read(), the calculation would | |
2028 | * work with no changes because: | |
2029 | * - event is guaranteed scheduled in | |
2030 | * - no scheduled out in between | |
2031 | * - thus the timestamp would be the same | |
2032 | * | |
2033 | * But this is a bit hairy. | |
2034 | * | |
2035 | * So instead, we have an explicit cgroup call to remain | |
2036 | * within the time time source all along. We believe it | |
2037 | * is cleaner and simpler to understand. | |
2038 | */ | |
2039 | if (is_cgroup_event(event)) | |
2040 | perf_cgroup_set_shadow_time(event, tstamp); | |
2041 | else | |
2042 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
2043 | } | |
2044 | ||
4fe757dd PZ |
2045 | #define MAX_INTERRUPTS (~0ULL) |
2046 | ||
2047 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2048 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2049 | |
235c7fc7 | 2050 | static int |
9ffcfa6f | 2051 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2052 | struct perf_cpu_context *cpuctx, |
6e37738a | 2053 | struct perf_event_context *ctx) |
235c7fc7 | 2054 | { |
4158755d | 2055 | u64 tstamp = perf_event_time(event); |
44377277 | 2056 | int ret = 0; |
4158755d | 2057 | |
63342411 PZ |
2058 | lockdep_assert_held(&ctx->lock); |
2059 | ||
cdd6c482 | 2060 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2061 | return 0; |
2062 | ||
95ff4ca2 AS |
2063 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2064 | /* | |
2065 | * Order event::oncpu write to happen before the ACTIVE state | |
2066 | * is visible. | |
2067 | */ | |
2068 | smp_wmb(); | |
2069 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
2070 | |
2071 | /* | |
2072 | * Unthrottle events, since we scheduled we might have missed several | |
2073 | * ticks already, also for a heavily scheduling task there is little | |
2074 | * guarantee it'll get a tick in a timely manner. | |
2075 | */ | |
2076 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2077 | perf_log_throttle(event, 1); | |
2078 | event->hw.interrupts = 0; | |
2079 | } | |
2080 | ||
235c7fc7 IM |
2081 | /* |
2082 | * The new state must be visible before we turn it on in the hardware: | |
2083 | */ | |
2084 | smp_wmb(); | |
2085 | ||
44377277 AS |
2086 | perf_pmu_disable(event->pmu); |
2087 | ||
72f669c0 SL |
2088 | perf_set_shadow_time(event, ctx, tstamp); |
2089 | ||
ec0d7729 AS |
2090 | perf_log_itrace_start(event); |
2091 | ||
a4eaf7f1 | 2092 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
2093 | event->state = PERF_EVENT_STATE_INACTIVE; |
2094 | event->oncpu = -1; | |
44377277 AS |
2095 | ret = -EAGAIN; |
2096 | goto out; | |
235c7fc7 IM |
2097 | } |
2098 | ||
00a2916f PZ |
2099 | event->tstamp_running += tstamp - event->tstamp_stopped; |
2100 | ||
cdd6c482 | 2101 | if (!is_software_event(event)) |
3b6f9e5c | 2102 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2103 | if (!ctx->nr_active++) |
2104 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2105 | if (event->attr.freq && event->attr.sample_freq) |
2106 | ctx->nr_freq++; | |
235c7fc7 | 2107 | |
cdd6c482 | 2108 | if (event->attr.exclusive) |
3b6f9e5c PM |
2109 | cpuctx->exclusive = 1; |
2110 | ||
44377277 AS |
2111 | out: |
2112 | perf_pmu_enable(event->pmu); | |
2113 | ||
2114 | return ret; | |
235c7fc7 IM |
2115 | } |
2116 | ||
6751b71e | 2117 | static int |
cdd6c482 | 2118 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2119 | struct perf_cpu_context *cpuctx, |
6e37738a | 2120 | struct perf_event_context *ctx) |
6751b71e | 2121 | { |
6bde9b6c | 2122 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2123 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2124 | u64 now = ctx->time; |
2125 | bool simulate = false; | |
6751b71e | 2126 | |
cdd6c482 | 2127 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2128 | return 0; |
2129 | ||
fbbe0701 | 2130 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2131 | |
9ffcfa6f | 2132 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2133 | pmu->cancel_txn(pmu); |
272325c4 | 2134 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2135 | return -EAGAIN; |
90151c35 | 2136 | } |
6751b71e PM |
2137 | |
2138 | /* | |
2139 | * Schedule in siblings as one group (if any): | |
2140 | */ | |
cdd6c482 | 2141 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2142 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2143 | partial_group = event; |
6751b71e PM |
2144 | goto group_error; |
2145 | } | |
2146 | } | |
2147 | ||
9ffcfa6f | 2148 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2149 | return 0; |
9ffcfa6f | 2150 | |
6751b71e PM |
2151 | group_error: |
2152 | /* | |
2153 | * Groups can be scheduled in as one unit only, so undo any | |
2154 | * partial group before returning: | |
d7842da4 SE |
2155 | * The events up to the failed event are scheduled out normally, |
2156 | * tstamp_stopped will be updated. | |
2157 | * | |
2158 | * The failed events and the remaining siblings need to have | |
2159 | * their timings updated as if they had gone thru event_sched_in() | |
2160 | * and event_sched_out(). This is required to get consistent timings | |
2161 | * across the group. This also takes care of the case where the group | |
2162 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2163 | * the time the event was actually stopped, such that time delta | |
2164 | * calculation in update_event_times() is correct. | |
6751b71e | 2165 | */ |
cdd6c482 IM |
2166 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2167 | if (event == partial_group) | |
d7842da4 SE |
2168 | simulate = true; |
2169 | ||
2170 | if (simulate) { | |
2171 | event->tstamp_running += now - event->tstamp_stopped; | |
2172 | event->tstamp_stopped = now; | |
2173 | } else { | |
2174 | event_sched_out(event, cpuctx, ctx); | |
2175 | } | |
6751b71e | 2176 | } |
9ffcfa6f | 2177 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2178 | |
ad5133b7 | 2179 | pmu->cancel_txn(pmu); |
90151c35 | 2180 | |
272325c4 | 2181 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2182 | |
6751b71e PM |
2183 | return -EAGAIN; |
2184 | } | |
2185 | ||
3b6f9e5c | 2186 | /* |
cdd6c482 | 2187 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2188 | */ |
cdd6c482 | 2189 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2190 | struct perf_cpu_context *cpuctx, |
2191 | int can_add_hw) | |
2192 | { | |
2193 | /* | |
cdd6c482 | 2194 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2195 | */ |
4ff6a8de | 2196 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2197 | return 1; |
2198 | /* | |
2199 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2200 | * events can go on. |
3b6f9e5c PM |
2201 | */ |
2202 | if (cpuctx->exclusive) | |
2203 | return 0; | |
2204 | /* | |
2205 | * If this group is exclusive and there are already | |
cdd6c482 | 2206 | * events on the CPU, it can't go on. |
3b6f9e5c | 2207 | */ |
cdd6c482 | 2208 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2209 | return 0; |
2210 | /* | |
2211 | * Otherwise, try to add it if all previous groups were able | |
2212 | * to go on. | |
2213 | */ | |
2214 | return can_add_hw; | |
2215 | } | |
2216 | ||
cdd6c482 IM |
2217 | static void add_event_to_ctx(struct perf_event *event, |
2218 | struct perf_event_context *ctx) | |
53cfbf59 | 2219 | { |
4158755d SE |
2220 | u64 tstamp = perf_event_time(event); |
2221 | ||
cdd6c482 | 2222 | list_add_event(event, ctx); |
8a49542c | 2223 | perf_group_attach(event); |
4158755d SE |
2224 | event->tstamp_enabled = tstamp; |
2225 | event->tstamp_running = tstamp; | |
2226 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2227 | } |
2228 | ||
bd2afa49 PZ |
2229 | static void ctx_sched_out(struct perf_event_context *ctx, |
2230 | struct perf_cpu_context *cpuctx, | |
2231 | enum event_type_t event_type); | |
2c29ef0f PZ |
2232 | static void |
2233 | ctx_sched_in(struct perf_event_context *ctx, | |
2234 | struct perf_cpu_context *cpuctx, | |
2235 | enum event_type_t event_type, | |
2236 | struct task_struct *task); | |
fe4b04fa | 2237 | |
bd2afa49 | 2238 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2239 | struct perf_event_context *ctx, |
2240 | enum event_type_t event_type) | |
bd2afa49 PZ |
2241 | { |
2242 | if (!cpuctx->task_ctx) | |
2243 | return; | |
2244 | ||
2245 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2246 | return; | |
2247 | ||
487f05e1 | 2248 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2249 | } |
2250 | ||
dce5855b PZ |
2251 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2252 | struct perf_event_context *ctx, | |
2253 | struct task_struct *task) | |
2254 | { | |
2255 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2256 | if (ctx) | |
2257 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2258 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2259 | if (ctx) | |
2260 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2261 | } | |
2262 | ||
487f05e1 AS |
2263 | /* |
2264 | * We want to maintain the following priority of scheduling: | |
2265 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2266 | * - task pinned (EVENT_PINNED) | |
2267 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2268 | * - task flexible (EVENT_FLEXIBLE). | |
2269 | * | |
2270 | * In order to avoid unscheduling and scheduling back in everything every | |
2271 | * time an event is added, only do it for the groups of equal priority and | |
2272 | * below. | |
2273 | * | |
2274 | * This can be called after a batch operation on task events, in which case | |
2275 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2276 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2277 | */ | |
3e349507 | 2278 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2279 | struct perf_event_context *task_ctx, |
2280 | enum event_type_t event_type) | |
0017960f | 2281 | { |
487f05e1 AS |
2282 | enum event_type_t ctx_event_type = event_type & EVENT_ALL; |
2283 | bool cpu_event = !!(event_type & EVENT_CPU); | |
2284 | ||
2285 | /* | |
2286 | * If pinned groups are involved, flexible groups also need to be | |
2287 | * scheduled out. | |
2288 | */ | |
2289 | if (event_type & EVENT_PINNED) | |
2290 | event_type |= EVENT_FLEXIBLE; | |
2291 | ||
3e349507 PZ |
2292 | perf_pmu_disable(cpuctx->ctx.pmu); |
2293 | if (task_ctx) | |
487f05e1 AS |
2294 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2295 | ||
2296 | /* | |
2297 | * Decide which cpu ctx groups to schedule out based on the types | |
2298 | * of events that caused rescheduling: | |
2299 | * - EVENT_CPU: schedule out corresponding groups; | |
2300 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2301 | * - otherwise, do nothing more. | |
2302 | */ | |
2303 | if (cpu_event) | |
2304 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2305 | else if (ctx_event_type & EVENT_PINNED) | |
2306 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2307 | ||
3e349507 PZ |
2308 | perf_event_sched_in(cpuctx, task_ctx, current); |
2309 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2310 | } |
2311 | ||
0793a61d | 2312 | /* |
cdd6c482 | 2313 | * Cross CPU call to install and enable a performance event |
682076ae | 2314 | * |
a096309b PZ |
2315 | * Very similar to remote_function() + event_function() but cannot assume that |
2316 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2317 | */ |
fe4b04fa | 2318 | static int __perf_install_in_context(void *info) |
0793a61d | 2319 | { |
a096309b PZ |
2320 | struct perf_event *event = info; |
2321 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2322 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2323 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2324 | bool reprogram = true; |
a096309b | 2325 | int ret = 0; |
0793a61d | 2326 | |
63b6da39 | 2327 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2328 | if (ctx->task) { |
b58f6b0d PZ |
2329 | raw_spin_lock(&ctx->lock); |
2330 | task_ctx = ctx; | |
a096309b | 2331 | |
63cae12b | 2332 | reprogram = (ctx->task == current); |
b58f6b0d | 2333 | |
39a43640 | 2334 | /* |
63cae12b PZ |
2335 | * If the task is running, it must be running on this CPU, |
2336 | * otherwise we cannot reprogram things. | |
2337 | * | |
2338 | * If its not running, we don't care, ctx->lock will | |
2339 | * serialize against it becoming runnable. | |
39a43640 | 2340 | */ |
63cae12b PZ |
2341 | if (task_curr(ctx->task) && !reprogram) { |
2342 | ret = -ESRCH; | |
2343 | goto unlock; | |
2344 | } | |
a096309b | 2345 | |
63cae12b | 2346 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2347 | } else if (task_ctx) { |
2348 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2349 | } |
b58f6b0d | 2350 | |
63cae12b | 2351 | if (reprogram) { |
a096309b PZ |
2352 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2353 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2354 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2355 | } else { |
2356 | add_event_to_ctx(event, ctx); | |
2357 | } | |
2358 | ||
63b6da39 | 2359 | unlock: |
2c29ef0f | 2360 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2361 | |
a096309b | 2362 | return ret; |
0793a61d TG |
2363 | } |
2364 | ||
2365 | /* | |
a096309b PZ |
2366 | * Attach a performance event to a context. |
2367 | * | |
2368 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2369 | */ |
2370 | static void | |
cdd6c482 IM |
2371 | perf_install_in_context(struct perf_event_context *ctx, |
2372 | struct perf_event *event, | |
0793a61d TG |
2373 | int cpu) |
2374 | { | |
a096309b | 2375 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2376 | |
fe4b04fa PZ |
2377 | lockdep_assert_held(&ctx->mutex); |
2378 | ||
0cda4c02 YZ |
2379 | if (event->cpu != -1) |
2380 | event->cpu = cpu; | |
c3f00c70 | 2381 | |
0b8f1e2e PZ |
2382 | /* |
2383 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2384 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2385 | */ | |
2386 | smp_store_release(&event->ctx, ctx); | |
2387 | ||
a096309b PZ |
2388 | if (!task) { |
2389 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2390 | return; | |
2391 | } | |
2392 | ||
2393 | /* | |
2394 | * Should not happen, we validate the ctx is still alive before calling. | |
2395 | */ | |
2396 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2397 | return; | |
2398 | ||
39a43640 PZ |
2399 | /* |
2400 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2401 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2402 | * |
2403 | * Instead we use task_curr(), which tells us if the task is running. | |
2404 | * However, since we use task_curr() outside of rq::lock, we can race | |
2405 | * against the actual state. This means the result can be wrong. | |
2406 | * | |
2407 | * If we get a false positive, we retry, this is harmless. | |
2408 | * | |
2409 | * If we get a false negative, things are complicated. If we are after | |
2410 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2411 | * value must be correct. If we're before, it doesn't matter since | |
2412 | * perf_event_context_sched_in() will program the counter. | |
2413 | * | |
2414 | * However, this hinges on the remote context switch having observed | |
2415 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2416 | * ctx::lock in perf_event_context_sched_in(). | |
2417 | * | |
2418 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2419 | * we know any future context switch of task must see the | |
2420 | * perf_event_ctpx[] store. | |
39a43640 | 2421 | */ |
63cae12b | 2422 | |
63b6da39 | 2423 | /* |
63cae12b PZ |
2424 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2425 | * task_cpu() load, such that if the IPI then does not find the task | |
2426 | * running, a future context switch of that task must observe the | |
2427 | * store. | |
63b6da39 | 2428 | */ |
63cae12b PZ |
2429 | smp_mb(); |
2430 | again: | |
2431 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2432 | return; |
2433 | ||
2434 | raw_spin_lock_irq(&ctx->lock); | |
2435 | task = ctx->task; | |
84c4e620 | 2436 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2437 | /* |
2438 | * Cannot happen because we already checked above (which also | |
2439 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2440 | * against perf_event_exit_task_context(). | |
2441 | */ | |
63b6da39 PZ |
2442 | raw_spin_unlock_irq(&ctx->lock); |
2443 | return; | |
2444 | } | |
39a43640 | 2445 | /* |
63cae12b PZ |
2446 | * If the task is not running, ctx->lock will avoid it becoming so, |
2447 | * thus we can safely install the event. | |
39a43640 | 2448 | */ |
63cae12b PZ |
2449 | if (task_curr(task)) { |
2450 | raw_spin_unlock_irq(&ctx->lock); | |
2451 | goto again; | |
2452 | } | |
2453 | add_event_to_ctx(event, ctx); | |
2454 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2455 | } |
2456 | ||
fa289bec | 2457 | /* |
cdd6c482 | 2458 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2459 | * Enabling the leader of a group effectively enables all |
2460 | * the group members that aren't explicitly disabled, so we | |
2461 | * have to update their ->tstamp_enabled also. | |
2462 | * Note: this works for group members as well as group leaders | |
2463 | * since the non-leader members' sibling_lists will be empty. | |
2464 | */ | |
1d9b482e | 2465 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2466 | { |
cdd6c482 | 2467 | struct perf_event *sub; |
4158755d | 2468 | u64 tstamp = perf_event_time(event); |
fa289bec | 2469 | |
cdd6c482 | 2470 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2471 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2472 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2473 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2474 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2475 | } |
fa289bec PM |
2476 | } |
2477 | ||
d859e29f | 2478 | /* |
cdd6c482 | 2479 | * Cross CPU call to enable a performance event |
d859e29f | 2480 | */ |
fae3fde6 PZ |
2481 | static void __perf_event_enable(struct perf_event *event, |
2482 | struct perf_cpu_context *cpuctx, | |
2483 | struct perf_event_context *ctx, | |
2484 | void *info) | |
04289bb9 | 2485 | { |
cdd6c482 | 2486 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2487 | struct perf_event_context *task_ctx; |
04289bb9 | 2488 | |
6e801e01 PZ |
2489 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2490 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2491 | return; |
3cbed429 | 2492 | |
bd2afa49 PZ |
2493 | if (ctx->is_active) |
2494 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2495 | ||
1d9b482e | 2496 | __perf_event_mark_enabled(event); |
04289bb9 | 2497 | |
fae3fde6 PZ |
2498 | if (!ctx->is_active) |
2499 | return; | |
2500 | ||
e5d1367f | 2501 | if (!event_filter_match(event)) { |
bd2afa49 | 2502 | if (is_cgroup_event(event)) |
e5d1367f | 2503 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2504 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2505 | return; |
e5d1367f | 2506 | } |
f4c4176f | 2507 | |
04289bb9 | 2508 | /* |
cdd6c482 | 2509 | * If the event is in a group and isn't the group leader, |
d859e29f | 2510 | * then don't put it on unless the group is on. |
04289bb9 | 2511 | */ |
bd2afa49 PZ |
2512 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2513 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2514 | return; |
bd2afa49 | 2515 | } |
fe4b04fa | 2516 | |
fae3fde6 PZ |
2517 | task_ctx = cpuctx->task_ctx; |
2518 | if (ctx->task) | |
2519 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2520 | |
487f05e1 | 2521 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2522 | } |
2523 | ||
d859e29f | 2524 | /* |
cdd6c482 | 2525 | * Enable a event. |
c93f7669 | 2526 | * |
cdd6c482 IM |
2527 | * If event->ctx is a cloned context, callers must make sure that |
2528 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2529 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2530 | * perf_event_for_each_child or perf_event_for_each as described |
2531 | * for perf_event_disable. | |
d859e29f | 2532 | */ |
f63a8daa | 2533 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2534 | { |
cdd6c482 | 2535 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2536 | |
7b648018 | 2537 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2538 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2539 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2540 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2541 | return; |
2542 | } | |
2543 | ||
d859e29f | 2544 | /* |
cdd6c482 | 2545 | * If the event is in error state, clear that first. |
7b648018 PZ |
2546 | * |
2547 | * That way, if we see the event in error state below, we know that it | |
2548 | * has gone back into error state, as distinct from the task having | |
2549 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2550 | */ |
cdd6c482 IM |
2551 | if (event->state == PERF_EVENT_STATE_ERROR) |
2552 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2553 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2554 | |
fae3fde6 | 2555 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2556 | } |
f63a8daa PZ |
2557 | |
2558 | /* | |
2559 | * See perf_event_disable(); | |
2560 | */ | |
2561 | void perf_event_enable(struct perf_event *event) | |
2562 | { | |
2563 | struct perf_event_context *ctx; | |
2564 | ||
2565 | ctx = perf_event_ctx_lock(event); | |
2566 | _perf_event_enable(event); | |
2567 | perf_event_ctx_unlock(event, ctx); | |
2568 | } | |
dcfce4a0 | 2569 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2570 | |
375637bc AS |
2571 | struct stop_event_data { |
2572 | struct perf_event *event; | |
2573 | unsigned int restart; | |
2574 | }; | |
2575 | ||
95ff4ca2 AS |
2576 | static int __perf_event_stop(void *info) |
2577 | { | |
375637bc AS |
2578 | struct stop_event_data *sd = info; |
2579 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2580 | |
375637bc | 2581 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2582 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2583 | return 0; | |
2584 | ||
2585 | /* matches smp_wmb() in event_sched_in() */ | |
2586 | smp_rmb(); | |
2587 | ||
2588 | /* | |
2589 | * There is a window with interrupts enabled before we get here, | |
2590 | * so we need to check again lest we try to stop another CPU's event. | |
2591 | */ | |
2592 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2593 | return -EAGAIN; | |
2594 | ||
2595 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2596 | ||
375637bc AS |
2597 | /* |
2598 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2599 | * but it is only used for events with AUX ring buffer, and such | |
2600 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2601 | * see comments in perf_aux_output_begin(). | |
2602 | * | |
2603 | * Since this is happening on a event-local CPU, no trace is lost | |
2604 | * while restarting. | |
2605 | */ | |
2606 | if (sd->restart) | |
c9bbdd48 | 2607 | event->pmu->start(event, 0); |
375637bc | 2608 | |
95ff4ca2 AS |
2609 | return 0; |
2610 | } | |
2611 | ||
767ae086 | 2612 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2613 | { |
2614 | struct stop_event_data sd = { | |
2615 | .event = event, | |
767ae086 | 2616 | .restart = restart, |
375637bc AS |
2617 | }; |
2618 | int ret = 0; | |
2619 | ||
2620 | do { | |
2621 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2622 | return 0; | |
2623 | ||
2624 | /* matches smp_wmb() in event_sched_in() */ | |
2625 | smp_rmb(); | |
2626 | ||
2627 | /* | |
2628 | * We only want to restart ACTIVE events, so if the event goes | |
2629 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2630 | * fall through with ret==-ENXIO. | |
2631 | */ | |
2632 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2633 | __perf_event_stop, &sd); | |
2634 | } while (ret == -EAGAIN); | |
2635 | ||
2636 | return ret; | |
2637 | } | |
2638 | ||
2639 | /* | |
2640 | * In order to contain the amount of racy and tricky in the address filter | |
2641 | * configuration management, it is a two part process: | |
2642 | * | |
2643 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2644 | * we update the addresses of corresponding vmas in | |
2645 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2646 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2647 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2648 | * if the generation has changed since the previous call. | |
2649 | * | |
2650 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2651 | * | |
2652 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2653 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2654 | * ioctl; | |
2655 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2656 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2657 | * for reading; | |
2658 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2659 | * of exec. | |
2660 | */ | |
2661 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2662 | { | |
2663 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2664 | ||
2665 | if (!has_addr_filter(event)) | |
2666 | return; | |
2667 | ||
2668 | raw_spin_lock(&ifh->lock); | |
2669 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2670 | event->pmu->addr_filters_sync(event); | |
2671 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2672 | } | |
2673 | raw_spin_unlock(&ifh->lock); | |
2674 | } | |
2675 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2676 | ||
f63a8daa | 2677 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2678 | { |
2023b359 | 2679 | /* |
cdd6c482 | 2680 | * not supported on inherited events |
2023b359 | 2681 | */ |
2e939d1d | 2682 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2683 | return -EINVAL; |
2684 | ||
cdd6c482 | 2685 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2686 | _perf_event_enable(event); |
2023b359 PZ |
2687 | |
2688 | return 0; | |
79f14641 | 2689 | } |
f63a8daa PZ |
2690 | |
2691 | /* | |
2692 | * See perf_event_disable() | |
2693 | */ | |
2694 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2695 | { | |
2696 | struct perf_event_context *ctx; | |
2697 | int ret; | |
2698 | ||
2699 | ctx = perf_event_ctx_lock(event); | |
2700 | ret = _perf_event_refresh(event, refresh); | |
2701 | perf_event_ctx_unlock(event, ctx); | |
2702 | ||
2703 | return ret; | |
2704 | } | |
26ca5c11 | 2705 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2706 | |
5b0311e1 FW |
2707 | static void ctx_sched_out(struct perf_event_context *ctx, |
2708 | struct perf_cpu_context *cpuctx, | |
2709 | enum event_type_t event_type) | |
235c7fc7 | 2710 | { |
db24d33e | 2711 | int is_active = ctx->is_active; |
c994d613 | 2712 | struct perf_event *event; |
235c7fc7 | 2713 | |
c994d613 | 2714 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2715 | |
39a43640 PZ |
2716 | if (likely(!ctx->nr_events)) { |
2717 | /* | |
2718 | * See __perf_remove_from_context(). | |
2719 | */ | |
2720 | WARN_ON_ONCE(ctx->is_active); | |
2721 | if (ctx->task) | |
2722 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2723 | return; |
39a43640 PZ |
2724 | } |
2725 | ||
db24d33e | 2726 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2727 | if (!(ctx->is_active & EVENT_ALL)) |
2728 | ctx->is_active = 0; | |
2729 | ||
63e30d3e PZ |
2730 | if (ctx->task) { |
2731 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2732 | if (!ctx->is_active) | |
2733 | cpuctx->task_ctx = NULL; | |
2734 | } | |
facc4307 | 2735 | |
8fdc6539 PZ |
2736 | /* |
2737 | * Always update time if it was set; not only when it changes. | |
2738 | * Otherwise we can 'forget' to update time for any but the last | |
2739 | * context we sched out. For example: | |
2740 | * | |
2741 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2742 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2743 | * | |
2744 | * would only update time for the pinned events. | |
2745 | */ | |
3cbaa590 PZ |
2746 | if (is_active & EVENT_TIME) { |
2747 | /* update (and stop) ctx time */ | |
2748 | update_context_time(ctx); | |
2749 | update_cgrp_time_from_cpuctx(cpuctx); | |
2750 | } | |
2751 | ||
8fdc6539 PZ |
2752 | is_active ^= ctx->is_active; /* changed bits */ |
2753 | ||
3cbaa590 | 2754 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2755 | return; |
5b0311e1 | 2756 | |
075e0b00 | 2757 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2758 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2759 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2760 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2761 | } |
889ff015 | 2762 | |
3cbaa590 | 2763 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2764 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2765 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2766 | } |
1b9a644f | 2767 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2768 | } |
2769 | ||
564c2b21 | 2770 | /* |
5a3126d4 PZ |
2771 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2772 | * cloned from the same version of the same context. | |
2773 | * | |
2774 | * Equivalence is measured using a generation number in the context that is | |
2775 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2776 | * and list_del_event(). | |
564c2b21 | 2777 | */ |
cdd6c482 IM |
2778 | static int context_equiv(struct perf_event_context *ctx1, |
2779 | struct perf_event_context *ctx2) | |
564c2b21 | 2780 | { |
211de6eb PZ |
2781 | lockdep_assert_held(&ctx1->lock); |
2782 | lockdep_assert_held(&ctx2->lock); | |
2783 | ||
5a3126d4 PZ |
2784 | /* Pinning disables the swap optimization */ |
2785 | if (ctx1->pin_count || ctx2->pin_count) | |
2786 | return 0; | |
2787 | ||
2788 | /* If ctx1 is the parent of ctx2 */ | |
2789 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2790 | return 1; | |
2791 | ||
2792 | /* If ctx2 is the parent of ctx1 */ | |
2793 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2794 | return 1; | |
2795 | ||
2796 | /* | |
2797 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2798 | * hierarchy, see perf_event_init_context(). | |
2799 | */ | |
2800 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2801 | ctx1->parent_gen == ctx2->parent_gen) | |
2802 | return 1; | |
2803 | ||
2804 | /* Unmatched */ | |
2805 | return 0; | |
564c2b21 PM |
2806 | } |
2807 | ||
cdd6c482 IM |
2808 | static void __perf_event_sync_stat(struct perf_event *event, |
2809 | struct perf_event *next_event) | |
bfbd3381 PZ |
2810 | { |
2811 | u64 value; | |
2812 | ||
cdd6c482 | 2813 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2814 | return; |
2815 | ||
2816 | /* | |
cdd6c482 | 2817 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2818 | * because we're in the middle of a context switch and have IRQs |
2819 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2820 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2821 | * don't need to use it. |
2822 | */ | |
cdd6c482 IM |
2823 | switch (event->state) { |
2824 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2825 | event->pmu->read(event); |
2826 | /* fall-through */ | |
bfbd3381 | 2827 | |
cdd6c482 IM |
2828 | case PERF_EVENT_STATE_INACTIVE: |
2829 | update_event_times(event); | |
bfbd3381 PZ |
2830 | break; |
2831 | ||
2832 | default: | |
2833 | break; | |
2834 | } | |
2835 | ||
2836 | /* | |
cdd6c482 | 2837 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2838 | * values when we flip the contexts. |
2839 | */ | |
e7850595 PZ |
2840 | value = local64_read(&next_event->count); |
2841 | value = local64_xchg(&event->count, value); | |
2842 | local64_set(&next_event->count, value); | |
bfbd3381 | 2843 | |
cdd6c482 IM |
2844 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2845 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2846 | |
bfbd3381 | 2847 | /* |
19d2e755 | 2848 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2849 | */ |
cdd6c482 IM |
2850 | perf_event_update_userpage(event); |
2851 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2852 | } |
2853 | ||
cdd6c482 IM |
2854 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2855 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2856 | { |
cdd6c482 | 2857 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2858 | |
2859 | if (!ctx->nr_stat) | |
2860 | return; | |
2861 | ||
02ffdbc8 PZ |
2862 | update_context_time(ctx); |
2863 | ||
cdd6c482 IM |
2864 | event = list_first_entry(&ctx->event_list, |
2865 | struct perf_event, event_entry); | |
bfbd3381 | 2866 | |
cdd6c482 IM |
2867 | next_event = list_first_entry(&next_ctx->event_list, |
2868 | struct perf_event, event_entry); | |
bfbd3381 | 2869 | |
cdd6c482 IM |
2870 | while (&event->event_entry != &ctx->event_list && |
2871 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2872 | |
cdd6c482 | 2873 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2874 | |
cdd6c482 IM |
2875 | event = list_next_entry(event, event_entry); |
2876 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2877 | } |
2878 | } | |
2879 | ||
fe4b04fa PZ |
2880 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2881 | struct task_struct *next) | |
0793a61d | 2882 | { |
8dc85d54 | 2883 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2884 | struct perf_event_context *next_ctx; |
5a3126d4 | 2885 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2886 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2887 | int do_switch = 1; |
0793a61d | 2888 | |
108b02cf PZ |
2889 | if (likely(!ctx)) |
2890 | return; | |
10989fb2 | 2891 | |
108b02cf PZ |
2892 | cpuctx = __get_cpu_context(ctx); |
2893 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2894 | return; |
2895 | ||
c93f7669 | 2896 | rcu_read_lock(); |
8dc85d54 | 2897 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2898 | if (!next_ctx) |
2899 | goto unlock; | |
2900 | ||
2901 | parent = rcu_dereference(ctx->parent_ctx); | |
2902 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2903 | ||
2904 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2905 | if (!parent && !next_parent) |
5a3126d4 PZ |
2906 | goto unlock; |
2907 | ||
2908 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2909 | /* |
2910 | * Looks like the two contexts are clones, so we might be | |
2911 | * able to optimize the context switch. We lock both | |
2912 | * contexts and check that they are clones under the | |
2913 | * lock (including re-checking that neither has been | |
2914 | * uncloned in the meantime). It doesn't matter which | |
2915 | * order we take the locks because no other cpu could | |
2916 | * be trying to lock both of these tasks. | |
2917 | */ | |
e625cce1 TG |
2918 | raw_spin_lock(&ctx->lock); |
2919 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2920 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2921 | WRITE_ONCE(ctx->task, next); |
2922 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2923 | |
2924 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2925 | ||
63b6da39 PZ |
2926 | /* |
2927 | * RCU_INIT_POINTER here is safe because we've not | |
2928 | * modified the ctx and the above modification of | |
2929 | * ctx->task and ctx->task_ctx_data are immaterial | |
2930 | * since those values are always verified under | |
2931 | * ctx->lock which we're now holding. | |
2932 | */ | |
2933 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2934 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2935 | ||
c93f7669 | 2936 | do_switch = 0; |
bfbd3381 | 2937 | |
cdd6c482 | 2938 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2939 | } |
e625cce1 TG |
2940 | raw_spin_unlock(&next_ctx->lock); |
2941 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2942 | } |
5a3126d4 | 2943 | unlock: |
c93f7669 | 2944 | rcu_read_unlock(); |
564c2b21 | 2945 | |
c93f7669 | 2946 | if (do_switch) { |
facc4307 | 2947 | raw_spin_lock(&ctx->lock); |
487f05e1 | 2948 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 2949 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2950 | } |
0793a61d TG |
2951 | } |
2952 | ||
e48c1788 PZ |
2953 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2954 | ||
ba532500 YZ |
2955 | void perf_sched_cb_dec(struct pmu *pmu) |
2956 | { | |
e48c1788 PZ |
2957 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2958 | ||
ba532500 | 2959 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2960 | |
2961 | if (!--cpuctx->sched_cb_usage) | |
2962 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2963 | } |
2964 | ||
e48c1788 | 2965 | |
ba532500 YZ |
2966 | void perf_sched_cb_inc(struct pmu *pmu) |
2967 | { | |
e48c1788 PZ |
2968 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2969 | ||
2970 | if (!cpuctx->sched_cb_usage++) | |
2971 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2972 | ||
ba532500 YZ |
2973 | this_cpu_inc(perf_sched_cb_usages); |
2974 | } | |
2975 | ||
2976 | /* | |
2977 | * This function provides the context switch callback to the lower code | |
2978 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2979 | * |
2980 | * This callback is relevant even to per-cpu events; for example multi event | |
2981 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2982 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2983 | */ |
2984 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2985 | struct task_struct *next, | |
2986 | bool sched_in) | |
2987 | { | |
2988 | struct perf_cpu_context *cpuctx; | |
2989 | struct pmu *pmu; | |
ba532500 YZ |
2990 | |
2991 | if (prev == next) | |
2992 | return; | |
2993 | ||
e48c1788 | 2994 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 2995 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 2996 | |
e48c1788 PZ |
2997 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2998 | continue; | |
ba532500 | 2999 | |
e48c1788 PZ |
3000 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3001 | perf_pmu_disable(pmu); | |
ba532500 | 3002 | |
e48c1788 | 3003 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3004 | |
e48c1788 PZ |
3005 | perf_pmu_enable(pmu); |
3006 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3007 | } |
ba532500 YZ |
3008 | } |
3009 | ||
45ac1403 AH |
3010 | static void perf_event_switch(struct task_struct *task, |
3011 | struct task_struct *next_prev, bool sched_in); | |
3012 | ||
8dc85d54 PZ |
3013 | #define for_each_task_context_nr(ctxn) \ |
3014 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3015 | ||
3016 | /* | |
3017 | * Called from scheduler to remove the events of the current task, | |
3018 | * with interrupts disabled. | |
3019 | * | |
3020 | * We stop each event and update the event value in event->count. | |
3021 | * | |
3022 | * This does not protect us against NMI, but disable() | |
3023 | * sets the disabled bit in the control field of event _before_ | |
3024 | * accessing the event control register. If a NMI hits, then it will | |
3025 | * not restart the event. | |
3026 | */ | |
ab0cce56 JO |
3027 | void __perf_event_task_sched_out(struct task_struct *task, |
3028 | struct task_struct *next) | |
8dc85d54 PZ |
3029 | { |
3030 | int ctxn; | |
3031 | ||
ba532500 YZ |
3032 | if (__this_cpu_read(perf_sched_cb_usages)) |
3033 | perf_pmu_sched_task(task, next, false); | |
3034 | ||
45ac1403 AH |
3035 | if (atomic_read(&nr_switch_events)) |
3036 | perf_event_switch(task, next, false); | |
3037 | ||
8dc85d54 PZ |
3038 | for_each_task_context_nr(ctxn) |
3039 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3040 | |
3041 | /* | |
3042 | * if cgroup events exist on this CPU, then we need | |
3043 | * to check if we have to switch out PMU state. | |
3044 | * cgroup event are system-wide mode only | |
3045 | */ | |
4a32fea9 | 3046 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3047 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3048 | } |
3049 | ||
5b0311e1 FW |
3050 | /* |
3051 | * Called with IRQs disabled | |
3052 | */ | |
3053 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3054 | enum event_type_t event_type) | |
3055 | { | |
3056 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3057 | } |
3058 | ||
235c7fc7 | 3059 | static void |
5b0311e1 | 3060 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 3061 | struct perf_cpu_context *cpuctx) |
0793a61d | 3062 | { |
cdd6c482 | 3063 | struct perf_event *event; |
0793a61d | 3064 | |
889ff015 FW |
3065 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
3066 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3067 | continue; |
5632ab12 | 3068 | if (!event_filter_match(event)) |
3b6f9e5c PM |
3069 | continue; |
3070 | ||
e5d1367f SE |
3071 | /* may need to reset tstamp_enabled */ |
3072 | if (is_cgroup_event(event)) | |
3073 | perf_cgroup_mark_enabled(event, ctx); | |
3074 | ||
8c9ed8e1 | 3075 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 3076 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
3077 | |
3078 | /* | |
3079 | * If this pinned group hasn't been scheduled, | |
3080 | * put it in error state. | |
3081 | */ | |
cdd6c482 IM |
3082 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3083 | update_group_times(event); | |
3084 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 3085 | } |
3b6f9e5c | 3086 | } |
5b0311e1 FW |
3087 | } |
3088 | ||
3089 | static void | |
3090 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 3091 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
3092 | { |
3093 | struct perf_event *event; | |
3094 | int can_add_hw = 1; | |
3b6f9e5c | 3095 | |
889ff015 FW |
3096 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
3097 | /* Ignore events in OFF or ERROR state */ | |
3098 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3099 | continue; |
04289bb9 IM |
3100 | /* |
3101 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 3102 | * of events: |
04289bb9 | 3103 | */ |
5632ab12 | 3104 | if (!event_filter_match(event)) |
0793a61d TG |
3105 | continue; |
3106 | ||
e5d1367f SE |
3107 | /* may need to reset tstamp_enabled */ |
3108 | if (is_cgroup_event(event)) | |
3109 | perf_cgroup_mark_enabled(event, ctx); | |
3110 | ||
9ed6060d | 3111 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3112 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3113 | can_add_hw = 0; |
9ed6060d | 3114 | } |
0793a61d | 3115 | } |
5b0311e1 FW |
3116 | } |
3117 | ||
3118 | static void | |
3119 | ctx_sched_in(struct perf_event_context *ctx, | |
3120 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3121 | enum event_type_t event_type, |
3122 | struct task_struct *task) | |
5b0311e1 | 3123 | { |
db24d33e | 3124 | int is_active = ctx->is_active; |
c994d613 PZ |
3125 | u64 now; |
3126 | ||
3127 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3128 | |
5b0311e1 | 3129 | if (likely(!ctx->nr_events)) |
facc4307 | 3130 | return; |
5b0311e1 | 3131 | |
3cbaa590 | 3132 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3133 | if (ctx->task) { |
3134 | if (!is_active) | |
3135 | cpuctx->task_ctx = ctx; | |
3136 | else | |
3137 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3138 | } | |
3139 | ||
3cbaa590 PZ |
3140 | is_active ^= ctx->is_active; /* changed bits */ |
3141 | ||
3142 | if (is_active & EVENT_TIME) { | |
3143 | /* start ctx time */ | |
3144 | now = perf_clock(); | |
3145 | ctx->timestamp = now; | |
3146 | perf_cgroup_set_timestamp(task, ctx); | |
3147 | } | |
3148 | ||
5b0311e1 FW |
3149 | /* |
3150 | * First go through the list and put on any pinned groups | |
3151 | * in order to give them the best chance of going on. | |
3152 | */ | |
3cbaa590 | 3153 | if (is_active & EVENT_PINNED) |
6e37738a | 3154 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3155 | |
3156 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3157 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3158 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3159 | } |
3160 | ||
329c0e01 | 3161 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3162 | enum event_type_t event_type, |
3163 | struct task_struct *task) | |
329c0e01 FW |
3164 | { |
3165 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3166 | ||
e5d1367f | 3167 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3168 | } |
3169 | ||
e5d1367f SE |
3170 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3171 | struct task_struct *task) | |
235c7fc7 | 3172 | { |
108b02cf | 3173 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3174 | |
108b02cf | 3175 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3176 | if (cpuctx->task_ctx == ctx) |
3177 | return; | |
3178 | ||
facc4307 | 3179 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3180 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3181 | /* |
3182 | * We want to keep the following priority order: | |
3183 | * cpu pinned (that don't need to move), task pinned, | |
3184 | * cpu flexible, task flexible. | |
fe45bafb AS |
3185 | * |
3186 | * However, if task's ctx is not carrying any pinned | |
3187 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3188 | */ |
fe45bafb AS |
3189 | if (!list_empty(&ctx->pinned_groups)) |
3190 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3191 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3192 | perf_pmu_enable(ctx->pmu); |
3193 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3194 | } |
3195 | ||
8dc85d54 PZ |
3196 | /* |
3197 | * Called from scheduler to add the events of the current task | |
3198 | * with interrupts disabled. | |
3199 | * | |
3200 | * We restore the event value and then enable it. | |
3201 | * | |
3202 | * This does not protect us against NMI, but enable() | |
3203 | * sets the enabled bit in the control field of event _before_ | |
3204 | * accessing the event control register. If a NMI hits, then it will | |
3205 | * keep the event running. | |
3206 | */ | |
ab0cce56 JO |
3207 | void __perf_event_task_sched_in(struct task_struct *prev, |
3208 | struct task_struct *task) | |
8dc85d54 PZ |
3209 | { |
3210 | struct perf_event_context *ctx; | |
3211 | int ctxn; | |
3212 | ||
7e41d177 PZ |
3213 | /* |
3214 | * If cgroup events exist on this CPU, then we need to check if we have | |
3215 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3216 | * | |
3217 | * Since cgroup events are CPU events, we must schedule these in before | |
3218 | * we schedule in the task events. | |
3219 | */ | |
3220 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3221 | perf_cgroup_sched_in(prev, task); | |
3222 | ||
8dc85d54 PZ |
3223 | for_each_task_context_nr(ctxn) { |
3224 | ctx = task->perf_event_ctxp[ctxn]; | |
3225 | if (likely(!ctx)) | |
3226 | continue; | |
3227 | ||
e5d1367f | 3228 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3229 | } |
d010b332 | 3230 | |
45ac1403 AH |
3231 | if (atomic_read(&nr_switch_events)) |
3232 | perf_event_switch(task, prev, true); | |
3233 | ||
ba532500 YZ |
3234 | if (__this_cpu_read(perf_sched_cb_usages)) |
3235 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3236 | } |
3237 | ||
abd50713 PZ |
3238 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3239 | { | |
3240 | u64 frequency = event->attr.sample_freq; | |
3241 | u64 sec = NSEC_PER_SEC; | |
3242 | u64 divisor, dividend; | |
3243 | ||
3244 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3245 | ||
3246 | count_fls = fls64(count); | |
3247 | nsec_fls = fls64(nsec); | |
3248 | frequency_fls = fls64(frequency); | |
3249 | sec_fls = 30; | |
3250 | ||
3251 | /* | |
3252 | * We got @count in @nsec, with a target of sample_freq HZ | |
3253 | * the target period becomes: | |
3254 | * | |
3255 | * @count * 10^9 | |
3256 | * period = ------------------- | |
3257 | * @nsec * sample_freq | |
3258 | * | |
3259 | */ | |
3260 | ||
3261 | /* | |
3262 | * Reduce accuracy by one bit such that @a and @b converge | |
3263 | * to a similar magnitude. | |
3264 | */ | |
fe4b04fa | 3265 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3266 | do { \ |
3267 | if (a##_fls > b##_fls) { \ | |
3268 | a >>= 1; \ | |
3269 | a##_fls--; \ | |
3270 | } else { \ | |
3271 | b >>= 1; \ | |
3272 | b##_fls--; \ | |
3273 | } \ | |
3274 | } while (0) | |
3275 | ||
3276 | /* | |
3277 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3278 | * the other, so that finally we can do a u64/u64 division. | |
3279 | */ | |
3280 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3281 | REDUCE_FLS(nsec, frequency); | |
3282 | REDUCE_FLS(sec, count); | |
3283 | } | |
3284 | ||
3285 | if (count_fls + sec_fls > 64) { | |
3286 | divisor = nsec * frequency; | |
3287 | ||
3288 | while (count_fls + sec_fls > 64) { | |
3289 | REDUCE_FLS(count, sec); | |
3290 | divisor >>= 1; | |
3291 | } | |
3292 | ||
3293 | dividend = count * sec; | |
3294 | } else { | |
3295 | dividend = count * sec; | |
3296 | ||
3297 | while (nsec_fls + frequency_fls > 64) { | |
3298 | REDUCE_FLS(nsec, frequency); | |
3299 | dividend >>= 1; | |
3300 | } | |
3301 | ||
3302 | divisor = nsec * frequency; | |
3303 | } | |
3304 | ||
f6ab91ad PZ |
3305 | if (!divisor) |
3306 | return dividend; | |
3307 | ||
abd50713 PZ |
3308 | return div64_u64(dividend, divisor); |
3309 | } | |
3310 | ||
e050e3f0 SE |
3311 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3312 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3313 | ||
f39d47ff | 3314 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3315 | { |
cdd6c482 | 3316 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3317 | s64 period, sample_period; |
bd2b5b12 PZ |
3318 | s64 delta; |
3319 | ||
abd50713 | 3320 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3321 | |
3322 | delta = (s64)(period - hwc->sample_period); | |
3323 | delta = (delta + 7) / 8; /* low pass filter */ | |
3324 | ||
3325 | sample_period = hwc->sample_period + delta; | |
3326 | ||
3327 | if (!sample_period) | |
3328 | sample_period = 1; | |
3329 | ||
bd2b5b12 | 3330 | hwc->sample_period = sample_period; |
abd50713 | 3331 | |
e7850595 | 3332 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3333 | if (disable) |
3334 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3335 | ||
e7850595 | 3336 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3337 | |
3338 | if (disable) | |
3339 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3340 | } |
bd2b5b12 PZ |
3341 | } |
3342 | ||
e050e3f0 SE |
3343 | /* |
3344 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3345 | * events. At the same time, make sure, having freq events does not change | |
3346 | * the rate of unthrottling as that would introduce bias. | |
3347 | */ | |
3348 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3349 | int needs_unthr) | |
60db5e09 | 3350 | { |
cdd6c482 IM |
3351 | struct perf_event *event; |
3352 | struct hw_perf_event *hwc; | |
e050e3f0 | 3353 | u64 now, period = TICK_NSEC; |
abd50713 | 3354 | s64 delta; |
60db5e09 | 3355 | |
e050e3f0 SE |
3356 | /* |
3357 | * only need to iterate over all events iff: | |
3358 | * - context have events in frequency mode (needs freq adjust) | |
3359 | * - there are events to unthrottle on this cpu | |
3360 | */ | |
3361 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3362 | return; |
3363 | ||
e050e3f0 | 3364 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3365 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3366 | |
03541f8b | 3367 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3368 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3369 | continue; |
3370 | ||
5632ab12 | 3371 | if (!event_filter_match(event)) |
5d27c23d PZ |
3372 | continue; |
3373 | ||
44377277 AS |
3374 | perf_pmu_disable(event->pmu); |
3375 | ||
cdd6c482 | 3376 | hwc = &event->hw; |
6a24ed6c | 3377 | |
ae23bff1 | 3378 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3379 | hwc->interrupts = 0; |
cdd6c482 | 3380 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3381 | event->pmu->start(event, 0); |
a78ac325 PZ |
3382 | } |
3383 | ||
cdd6c482 | 3384 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3385 | goto next; |
60db5e09 | 3386 | |
e050e3f0 SE |
3387 | /* |
3388 | * stop the event and update event->count | |
3389 | */ | |
3390 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3391 | ||
e7850595 | 3392 | now = local64_read(&event->count); |
abd50713 PZ |
3393 | delta = now - hwc->freq_count_stamp; |
3394 | hwc->freq_count_stamp = now; | |
60db5e09 | 3395 | |
e050e3f0 SE |
3396 | /* |
3397 | * restart the event | |
3398 | * reload only if value has changed | |
f39d47ff SE |
3399 | * we have stopped the event so tell that |
3400 | * to perf_adjust_period() to avoid stopping it | |
3401 | * twice. | |
e050e3f0 | 3402 | */ |
abd50713 | 3403 | if (delta > 0) |
f39d47ff | 3404 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3405 | |
3406 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3407 | next: |
3408 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3409 | } |
e050e3f0 | 3410 | |
f39d47ff | 3411 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3412 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3413 | } |
3414 | ||
235c7fc7 | 3415 | /* |
cdd6c482 | 3416 | * Round-robin a context's events: |
235c7fc7 | 3417 | */ |
cdd6c482 | 3418 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3419 | { |
dddd3379 TG |
3420 | /* |
3421 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3422 | * disabled by the inheritance code. | |
3423 | */ | |
3424 | if (!ctx->rotate_disable) | |
3425 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3426 | } |
3427 | ||
9e630205 | 3428 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3429 | { |
8dc85d54 | 3430 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3431 | int rotate = 0; |
7fc23a53 | 3432 | |
b5ab4cd5 | 3433 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3434 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3435 | rotate = 1; | |
3436 | } | |
235c7fc7 | 3437 | |
8dc85d54 | 3438 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3439 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3440 | if (ctx->nr_events != ctx->nr_active) |
3441 | rotate = 1; | |
3442 | } | |
9717e6cd | 3443 | |
e050e3f0 | 3444 | if (!rotate) |
0f5a2601 PZ |
3445 | goto done; |
3446 | ||
facc4307 | 3447 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3448 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3449 | |
e050e3f0 SE |
3450 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3451 | if (ctx) | |
3452 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3453 | |
e050e3f0 SE |
3454 | rotate_ctx(&cpuctx->ctx); |
3455 | if (ctx) | |
3456 | rotate_ctx(ctx); | |
235c7fc7 | 3457 | |
e050e3f0 | 3458 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3459 | |
0f5a2601 PZ |
3460 | perf_pmu_enable(cpuctx->ctx.pmu); |
3461 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3462 | done: |
9e630205 SE |
3463 | |
3464 | return rotate; | |
e9d2b064 PZ |
3465 | } |
3466 | ||
3467 | void perf_event_task_tick(void) | |
3468 | { | |
2fde4f94 MR |
3469 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3470 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3471 | int throttled; |
b5ab4cd5 | 3472 | |
e9d2b064 PZ |
3473 | WARN_ON(!irqs_disabled()); |
3474 | ||
e050e3f0 SE |
3475 | __this_cpu_inc(perf_throttled_seq); |
3476 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3477 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3478 | |
2fde4f94 | 3479 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3480 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3481 | } |
3482 | ||
889ff015 FW |
3483 | static int event_enable_on_exec(struct perf_event *event, |
3484 | struct perf_event_context *ctx) | |
3485 | { | |
3486 | if (!event->attr.enable_on_exec) | |
3487 | return 0; | |
3488 | ||
3489 | event->attr.enable_on_exec = 0; | |
3490 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3491 | return 0; | |
3492 | ||
1d9b482e | 3493 | __perf_event_mark_enabled(event); |
889ff015 FW |
3494 | |
3495 | return 1; | |
3496 | } | |
3497 | ||
57e7986e | 3498 | /* |
cdd6c482 | 3499 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3500 | * This expects task == current. |
3501 | */ | |
c1274499 | 3502 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3503 | { |
c1274499 | 3504 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3505 | enum event_type_t event_type = 0; |
3e349507 | 3506 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3507 | struct perf_event *event; |
57e7986e PM |
3508 | unsigned long flags; |
3509 | int enabled = 0; | |
3510 | ||
3511 | local_irq_save(flags); | |
c1274499 | 3512 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3513 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3514 | goto out; |
3515 | ||
3e349507 PZ |
3516 | cpuctx = __get_cpu_context(ctx); |
3517 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3518 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3519 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3520 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3521 | event_type |= get_event_type(event); |
3522 | } | |
57e7986e PM |
3523 | |
3524 | /* | |
3e349507 | 3525 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3526 | */ |
3e349507 | 3527 | if (enabled) { |
211de6eb | 3528 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3529 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3530 | } else { |
3531 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3532 | } |
3533 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3534 | |
9ed6060d | 3535 | out: |
57e7986e | 3536 | local_irq_restore(flags); |
211de6eb PZ |
3537 | |
3538 | if (clone_ctx) | |
3539 | put_ctx(clone_ctx); | |
57e7986e PM |
3540 | } |
3541 | ||
0492d4c5 PZ |
3542 | struct perf_read_data { |
3543 | struct perf_event *event; | |
3544 | bool group; | |
7d88962e | 3545 | int ret; |
0492d4c5 PZ |
3546 | }; |
3547 | ||
451d24d1 | 3548 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3549 | { |
d6a2f903 DCC |
3550 | u16 local_pkg, event_pkg; |
3551 | ||
3552 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3553 | int local_cpu = smp_processor_id(); |
3554 | ||
3555 | event_pkg = topology_physical_package_id(event_cpu); | |
3556 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3557 | |
3558 | if (event_pkg == local_pkg) | |
3559 | return local_cpu; | |
3560 | } | |
3561 | ||
3562 | return event_cpu; | |
3563 | } | |
3564 | ||
0793a61d | 3565 | /* |
cdd6c482 | 3566 | * Cross CPU call to read the hardware event |
0793a61d | 3567 | */ |
cdd6c482 | 3568 | static void __perf_event_read(void *info) |
0793a61d | 3569 | { |
0492d4c5 PZ |
3570 | struct perf_read_data *data = info; |
3571 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3572 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3573 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3574 | struct pmu *pmu = event->pmu; |
621a01ea | 3575 | |
e1ac3614 PM |
3576 | /* |
3577 | * If this is a task context, we need to check whether it is | |
3578 | * the current task context of this cpu. If not it has been | |
3579 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3580 | * event->count would have been updated to a recent sample |
3581 | * when the event was scheduled out. | |
e1ac3614 PM |
3582 | */ |
3583 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3584 | return; | |
3585 | ||
e625cce1 | 3586 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3587 | if (ctx->is_active) { |
542e72fc | 3588 | update_context_time(ctx); |
e5d1367f SE |
3589 | update_cgrp_time_from_event(event); |
3590 | } | |
0492d4c5 | 3591 | |
cdd6c482 | 3592 | update_event_times(event); |
4a00c16e SB |
3593 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3594 | goto unlock; | |
0492d4c5 | 3595 | |
4a00c16e SB |
3596 | if (!data->group) { |
3597 | pmu->read(event); | |
3598 | data->ret = 0; | |
0492d4c5 | 3599 | goto unlock; |
4a00c16e SB |
3600 | } |
3601 | ||
3602 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3603 | ||
3604 | pmu->read(event); | |
0492d4c5 PZ |
3605 | |
3606 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3607 | update_event_times(sub); | |
4a00c16e SB |
3608 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3609 | /* | |
3610 | * Use sibling's PMU rather than @event's since | |
3611 | * sibling could be on different (eg: software) PMU. | |
3612 | */ | |
0492d4c5 | 3613 | sub->pmu->read(sub); |
4a00c16e | 3614 | } |
0492d4c5 | 3615 | } |
4a00c16e SB |
3616 | |
3617 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3618 | |
3619 | unlock: | |
e625cce1 | 3620 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3621 | } |
3622 | ||
b5e58793 PZ |
3623 | static inline u64 perf_event_count(struct perf_event *event) |
3624 | { | |
eacd3ecc MF |
3625 | if (event->pmu->count) |
3626 | return event->pmu->count(event); | |
3627 | ||
3628 | return __perf_event_count(event); | |
b5e58793 PZ |
3629 | } |
3630 | ||
ffe8690c KX |
3631 | /* |
3632 | * NMI-safe method to read a local event, that is an event that | |
3633 | * is: | |
3634 | * - either for the current task, or for this CPU | |
3635 | * - does not have inherit set, for inherited task events | |
3636 | * will not be local and we cannot read them atomically | |
3637 | * - must not have a pmu::count method | |
3638 | */ | |
3639 | u64 perf_event_read_local(struct perf_event *event) | |
3640 | { | |
3641 | unsigned long flags; | |
3642 | u64 val; | |
3643 | ||
3644 | /* | |
3645 | * Disabling interrupts avoids all counter scheduling (context | |
3646 | * switches, timer based rotation and IPIs). | |
3647 | */ | |
3648 | local_irq_save(flags); | |
3649 | ||
3650 | /* If this is a per-task event, it must be for current */ | |
3651 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3652 | event->hw.target != current); | |
3653 | ||
3654 | /* If this is a per-CPU event, it must be for this CPU */ | |
3655 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3656 | event->cpu != smp_processor_id()); | |
3657 | ||
3658 | /* | |
3659 | * It must not be an event with inherit set, we cannot read | |
3660 | * all child counters from atomic context. | |
3661 | */ | |
3662 | WARN_ON_ONCE(event->attr.inherit); | |
3663 | ||
3664 | /* | |
3665 | * It must not have a pmu::count method, those are not | |
3666 | * NMI safe. | |
3667 | */ | |
3668 | WARN_ON_ONCE(event->pmu->count); | |
3669 | ||
3670 | /* | |
3671 | * If the event is currently on this CPU, its either a per-task event, | |
3672 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3673 | * oncpu == -1). | |
3674 | */ | |
3675 | if (event->oncpu == smp_processor_id()) | |
3676 | event->pmu->read(event); | |
3677 | ||
3678 | val = local64_read(&event->count); | |
3679 | local_irq_restore(flags); | |
3680 | ||
3681 | return val; | |
3682 | } | |
3683 | ||
7d88962e | 3684 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3685 | { |
451d24d1 | 3686 | int event_cpu, ret = 0; |
7d88962e | 3687 | |
0793a61d | 3688 | /* |
cdd6c482 IM |
3689 | * If event is enabled and currently active on a CPU, update the |
3690 | * value in the event structure: | |
0793a61d | 3691 | */ |
cdd6c482 | 3692 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3693 | struct perf_read_data data = { |
3694 | .event = event, | |
3695 | .group = group, | |
7d88962e | 3696 | .ret = 0, |
0492d4c5 | 3697 | }; |
d6a2f903 | 3698 | |
451d24d1 PZ |
3699 | event_cpu = READ_ONCE(event->oncpu); |
3700 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
3701 | return 0; | |
3702 | ||
3703 | preempt_disable(); | |
3704 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 3705 | |
58763148 PZ |
3706 | /* |
3707 | * Purposely ignore the smp_call_function_single() return | |
3708 | * value. | |
3709 | * | |
451d24d1 | 3710 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
3711 | * scheduled out and that will have updated the event count. |
3712 | * | |
3713 | * Therefore, either way, we'll have an up-to-date event count | |
3714 | * after this. | |
3715 | */ | |
451d24d1 PZ |
3716 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
3717 | preempt_enable(); | |
58763148 | 3718 | ret = data.ret; |
cdd6c482 | 3719 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3720 | struct perf_event_context *ctx = event->ctx; |
3721 | unsigned long flags; | |
3722 | ||
e625cce1 | 3723 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3724 | /* |
3725 | * may read while context is not active | |
3726 | * (e.g., thread is blocked), in that case | |
3727 | * we cannot update context time | |
3728 | */ | |
e5d1367f | 3729 | if (ctx->is_active) { |
c530ccd9 | 3730 | update_context_time(ctx); |
e5d1367f SE |
3731 | update_cgrp_time_from_event(event); |
3732 | } | |
0492d4c5 PZ |
3733 | if (group) |
3734 | update_group_times(event); | |
3735 | else | |
3736 | update_event_times(event); | |
e625cce1 | 3737 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3738 | } |
7d88962e SB |
3739 | |
3740 | return ret; | |
0793a61d TG |
3741 | } |
3742 | ||
a63eaf34 | 3743 | /* |
cdd6c482 | 3744 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3745 | */ |
eb184479 | 3746 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3747 | { |
e625cce1 | 3748 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3749 | mutex_init(&ctx->mutex); |
2fde4f94 | 3750 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3751 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3752 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3753 | INIT_LIST_HEAD(&ctx->event_list); |
3754 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3755 | } |
3756 | ||
3757 | static struct perf_event_context * | |
3758 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3759 | { | |
3760 | struct perf_event_context *ctx; | |
3761 | ||
3762 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3763 | if (!ctx) | |
3764 | return NULL; | |
3765 | ||
3766 | __perf_event_init_context(ctx); | |
3767 | if (task) { | |
3768 | ctx->task = task; | |
3769 | get_task_struct(task); | |
0793a61d | 3770 | } |
eb184479 PZ |
3771 | ctx->pmu = pmu; |
3772 | ||
3773 | return ctx; | |
a63eaf34 PM |
3774 | } |
3775 | ||
2ebd4ffb MH |
3776 | static struct task_struct * |
3777 | find_lively_task_by_vpid(pid_t vpid) | |
3778 | { | |
3779 | struct task_struct *task; | |
0793a61d TG |
3780 | |
3781 | rcu_read_lock(); | |
2ebd4ffb | 3782 | if (!vpid) |
0793a61d TG |
3783 | task = current; |
3784 | else | |
2ebd4ffb | 3785 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3786 | if (task) |
3787 | get_task_struct(task); | |
3788 | rcu_read_unlock(); | |
3789 | ||
3790 | if (!task) | |
3791 | return ERR_PTR(-ESRCH); | |
3792 | ||
2ebd4ffb | 3793 | return task; |
2ebd4ffb MH |
3794 | } |
3795 | ||
fe4b04fa PZ |
3796 | /* |
3797 | * Returns a matching context with refcount and pincount. | |
3798 | */ | |
108b02cf | 3799 | static struct perf_event_context * |
4af57ef2 YZ |
3800 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3801 | struct perf_event *event) | |
0793a61d | 3802 | { |
211de6eb | 3803 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3804 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3805 | void *task_ctx_data = NULL; |
25346b93 | 3806 | unsigned long flags; |
8dc85d54 | 3807 | int ctxn, err; |
4af57ef2 | 3808 | int cpu = event->cpu; |
0793a61d | 3809 | |
22a4ec72 | 3810 | if (!task) { |
cdd6c482 | 3811 | /* Must be root to operate on a CPU event: */ |
0764771d | 3812 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3813 | return ERR_PTR(-EACCES); |
3814 | ||
0793a61d | 3815 | /* |
cdd6c482 | 3816 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3817 | * offline CPU and activate it when the CPU comes up, but |
3818 | * that's for later. | |
3819 | */ | |
f6325e30 | 3820 | if (!cpu_online(cpu)) |
0793a61d TG |
3821 | return ERR_PTR(-ENODEV); |
3822 | ||
108b02cf | 3823 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3824 | ctx = &cpuctx->ctx; |
c93f7669 | 3825 | get_ctx(ctx); |
fe4b04fa | 3826 | ++ctx->pin_count; |
0793a61d | 3827 | |
0793a61d TG |
3828 | return ctx; |
3829 | } | |
3830 | ||
8dc85d54 PZ |
3831 | err = -EINVAL; |
3832 | ctxn = pmu->task_ctx_nr; | |
3833 | if (ctxn < 0) | |
3834 | goto errout; | |
3835 | ||
4af57ef2 YZ |
3836 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3837 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3838 | if (!task_ctx_data) { | |
3839 | err = -ENOMEM; | |
3840 | goto errout; | |
3841 | } | |
3842 | } | |
3843 | ||
9ed6060d | 3844 | retry: |
8dc85d54 | 3845 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3846 | if (ctx) { |
211de6eb | 3847 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3848 | ++ctx->pin_count; |
4af57ef2 YZ |
3849 | |
3850 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3851 | ctx->task_ctx_data = task_ctx_data; | |
3852 | task_ctx_data = NULL; | |
3853 | } | |
e625cce1 | 3854 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3855 | |
3856 | if (clone_ctx) | |
3857 | put_ctx(clone_ctx); | |
9137fb28 | 3858 | } else { |
eb184479 | 3859 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3860 | err = -ENOMEM; |
3861 | if (!ctx) | |
3862 | goto errout; | |
eb184479 | 3863 | |
4af57ef2 YZ |
3864 | if (task_ctx_data) { |
3865 | ctx->task_ctx_data = task_ctx_data; | |
3866 | task_ctx_data = NULL; | |
3867 | } | |
3868 | ||
dbe08d82 ON |
3869 | err = 0; |
3870 | mutex_lock(&task->perf_event_mutex); | |
3871 | /* | |
3872 | * If it has already passed perf_event_exit_task(). | |
3873 | * we must see PF_EXITING, it takes this mutex too. | |
3874 | */ | |
3875 | if (task->flags & PF_EXITING) | |
3876 | err = -ESRCH; | |
3877 | else if (task->perf_event_ctxp[ctxn]) | |
3878 | err = -EAGAIN; | |
fe4b04fa | 3879 | else { |
9137fb28 | 3880 | get_ctx(ctx); |
fe4b04fa | 3881 | ++ctx->pin_count; |
dbe08d82 | 3882 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3883 | } |
dbe08d82 ON |
3884 | mutex_unlock(&task->perf_event_mutex); |
3885 | ||
3886 | if (unlikely(err)) { | |
9137fb28 | 3887 | put_ctx(ctx); |
dbe08d82 ON |
3888 | |
3889 | if (err == -EAGAIN) | |
3890 | goto retry; | |
3891 | goto errout; | |
a63eaf34 PM |
3892 | } |
3893 | } | |
3894 | ||
4af57ef2 | 3895 | kfree(task_ctx_data); |
0793a61d | 3896 | return ctx; |
c93f7669 | 3897 | |
9ed6060d | 3898 | errout: |
4af57ef2 | 3899 | kfree(task_ctx_data); |
c93f7669 | 3900 | return ERR_PTR(err); |
0793a61d TG |
3901 | } |
3902 | ||
6fb2915d | 3903 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3904 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3905 | |
cdd6c482 | 3906 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3907 | { |
cdd6c482 | 3908 | struct perf_event *event; |
592903cd | 3909 | |
cdd6c482 IM |
3910 | event = container_of(head, struct perf_event, rcu_head); |
3911 | if (event->ns) | |
3912 | put_pid_ns(event->ns); | |
6fb2915d | 3913 | perf_event_free_filter(event); |
cdd6c482 | 3914 | kfree(event); |
592903cd PZ |
3915 | } |
3916 | ||
b69cf536 PZ |
3917 | static void ring_buffer_attach(struct perf_event *event, |
3918 | struct ring_buffer *rb); | |
925d519a | 3919 | |
f2fb6bef KL |
3920 | static void detach_sb_event(struct perf_event *event) |
3921 | { | |
3922 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3923 | ||
3924 | raw_spin_lock(&pel->lock); | |
3925 | list_del_rcu(&event->sb_list); | |
3926 | raw_spin_unlock(&pel->lock); | |
3927 | } | |
3928 | ||
a4f144eb | 3929 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3930 | { |
a4f144eb DCC |
3931 | struct perf_event_attr *attr = &event->attr; |
3932 | ||
f2fb6bef | 3933 | if (event->parent) |
a4f144eb | 3934 | return false; |
f2fb6bef KL |
3935 | |
3936 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3937 | return false; |
f2fb6bef | 3938 | |
a4f144eb DCC |
3939 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3940 | attr->comm || attr->comm_exec || | |
3941 | attr->task || | |
3942 | attr->context_switch) | |
3943 | return true; | |
3944 | return false; | |
3945 | } | |
3946 | ||
3947 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3948 | { | |
3949 | if (is_sb_event(event)) | |
3950 | detach_sb_event(event); | |
f2fb6bef KL |
3951 | } |
3952 | ||
4beb31f3 | 3953 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3954 | { |
4beb31f3 FW |
3955 | if (event->parent) |
3956 | return; | |
3957 | ||
4beb31f3 FW |
3958 | if (is_cgroup_event(event)) |
3959 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3960 | } | |
925d519a | 3961 | |
555e0c1e FW |
3962 | #ifdef CONFIG_NO_HZ_FULL |
3963 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3964 | #endif | |
3965 | ||
3966 | static void unaccount_freq_event_nohz(void) | |
3967 | { | |
3968 | #ifdef CONFIG_NO_HZ_FULL | |
3969 | spin_lock(&nr_freq_lock); | |
3970 | if (atomic_dec_and_test(&nr_freq_events)) | |
3971 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3972 | spin_unlock(&nr_freq_lock); | |
3973 | #endif | |
3974 | } | |
3975 | ||
3976 | static void unaccount_freq_event(void) | |
3977 | { | |
3978 | if (tick_nohz_full_enabled()) | |
3979 | unaccount_freq_event_nohz(); | |
3980 | else | |
3981 | atomic_dec(&nr_freq_events); | |
3982 | } | |
3983 | ||
4beb31f3 FW |
3984 | static void unaccount_event(struct perf_event *event) |
3985 | { | |
25432ae9 PZ |
3986 | bool dec = false; |
3987 | ||
4beb31f3 FW |
3988 | if (event->parent) |
3989 | return; | |
3990 | ||
3991 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3992 | dec = true; |
4beb31f3 FW |
3993 | if (event->attr.mmap || event->attr.mmap_data) |
3994 | atomic_dec(&nr_mmap_events); | |
3995 | if (event->attr.comm) | |
3996 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
3997 | if (event->attr.namespaces) |
3998 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
3999 | if (event->attr.task) |
4000 | atomic_dec(&nr_task_events); | |
948b26b6 | 4001 | if (event->attr.freq) |
555e0c1e | 4002 | unaccount_freq_event(); |
45ac1403 | 4003 | if (event->attr.context_switch) { |
25432ae9 | 4004 | dec = true; |
45ac1403 AH |
4005 | atomic_dec(&nr_switch_events); |
4006 | } | |
4beb31f3 | 4007 | if (is_cgroup_event(event)) |
25432ae9 | 4008 | dec = true; |
4beb31f3 | 4009 | if (has_branch_stack(event)) |
25432ae9 PZ |
4010 | dec = true; |
4011 | ||
9107c89e PZ |
4012 | if (dec) { |
4013 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4014 | schedule_delayed_work(&perf_sched_work, HZ); | |
4015 | } | |
4beb31f3 FW |
4016 | |
4017 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4018 | |
4019 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4020 | } |
925d519a | 4021 | |
9107c89e PZ |
4022 | static void perf_sched_delayed(struct work_struct *work) |
4023 | { | |
4024 | mutex_lock(&perf_sched_mutex); | |
4025 | if (atomic_dec_and_test(&perf_sched_count)) | |
4026 | static_branch_disable(&perf_sched_events); | |
4027 | mutex_unlock(&perf_sched_mutex); | |
4028 | } | |
4029 | ||
bed5b25a AS |
4030 | /* |
4031 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4032 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4033 | * at a time, so we disallow creating events that might conflict, namely: | |
4034 | * | |
4035 | * 1) cpu-wide events in the presence of per-task events, | |
4036 | * 2) per-task events in the presence of cpu-wide events, | |
4037 | * 3) two matching events on the same context. | |
4038 | * | |
4039 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4040 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4041 | */ |
4042 | static int exclusive_event_init(struct perf_event *event) | |
4043 | { | |
4044 | struct pmu *pmu = event->pmu; | |
4045 | ||
4046 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4047 | return 0; | |
4048 | ||
4049 | /* | |
4050 | * Prevent co-existence of per-task and cpu-wide events on the | |
4051 | * same exclusive pmu. | |
4052 | * | |
4053 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4054 | * events on this "exclusive" pmu, positive means there are | |
4055 | * per-task events. | |
4056 | * | |
4057 | * Since this is called in perf_event_alloc() path, event::ctx | |
4058 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4059 | * to mean "per-task event", because unlike other attach states it | |
4060 | * never gets cleared. | |
4061 | */ | |
4062 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4063 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4064 | return -EBUSY; | |
4065 | } else { | |
4066 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4067 | return -EBUSY; | |
4068 | } | |
4069 | ||
4070 | return 0; | |
4071 | } | |
4072 | ||
4073 | static void exclusive_event_destroy(struct perf_event *event) | |
4074 | { | |
4075 | struct pmu *pmu = event->pmu; | |
4076 | ||
4077 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4078 | return; | |
4079 | ||
4080 | /* see comment in exclusive_event_init() */ | |
4081 | if (event->attach_state & PERF_ATTACH_TASK) | |
4082 | atomic_dec(&pmu->exclusive_cnt); | |
4083 | else | |
4084 | atomic_inc(&pmu->exclusive_cnt); | |
4085 | } | |
4086 | ||
4087 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4088 | { | |
3bf6215a | 4089 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4090 | (e1->cpu == e2->cpu || |
4091 | e1->cpu == -1 || | |
4092 | e2->cpu == -1)) | |
4093 | return true; | |
4094 | return false; | |
4095 | } | |
4096 | ||
4097 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4098 | static bool exclusive_event_installable(struct perf_event *event, | |
4099 | struct perf_event_context *ctx) | |
4100 | { | |
4101 | struct perf_event *iter_event; | |
4102 | struct pmu *pmu = event->pmu; | |
4103 | ||
4104 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4105 | return true; | |
4106 | ||
4107 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4108 | if (exclusive_event_match(iter_event, event)) | |
4109 | return false; | |
4110 | } | |
4111 | ||
4112 | return true; | |
4113 | } | |
4114 | ||
375637bc AS |
4115 | static void perf_addr_filters_splice(struct perf_event *event, |
4116 | struct list_head *head); | |
4117 | ||
683ede43 | 4118 | static void _free_event(struct perf_event *event) |
f1600952 | 4119 | { |
e360adbe | 4120 | irq_work_sync(&event->pending); |
925d519a | 4121 | |
4beb31f3 | 4122 | unaccount_event(event); |
9ee318a7 | 4123 | |
76369139 | 4124 | if (event->rb) { |
9bb5d40c PZ |
4125 | /* |
4126 | * Can happen when we close an event with re-directed output. | |
4127 | * | |
4128 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4129 | * over us; possibly making our ring_buffer_put() the last. | |
4130 | */ | |
4131 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4132 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4133 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4134 | } |
4135 | ||
e5d1367f SE |
4136 | if (is_cgroup_event(event)) |
4137 | perf_detach_cgroup(event); | |
4138 | ||
a0733e69 PZ |
4139 | if (!event->parent) { |
4140 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4141 | put_callchain_buffers(); | |
4142 | } | |
4143 | ||
4144 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4145 | perf_addr_filters_splice(event, NULL); |
4146 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4147 | |
4148 | if (event->destroy) | |
4149 | event->destroy(event); | |
4150 | ||
4151 | if (event->ctx) | |
4152 | put_ctx(event->ctx); | |
4153 | ||
62a92c8f AS |
4154 | exclusive_event_destroy(event); |
4155 | module_put(event->pmu->module); | |
a0733e69 PZ |
4156 | |
4157 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4158 | } |
4159 | ||
683ede43 PZ |
4160 | /* |
4161 | * Used to free events which have a known refcount of 1, such as in error paths | |
4162 | * where the event isn't exposed yet and inherited events. | |
4163 | */ | |
4164 | static void free_event(struct perf_event *event) | |
0793a61d | 4165 | { |
683ede43 PZ |
4166 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4167 | "unexpected event refcount: %ld; ptr=%p\n", | |
4168 | atomic_long_read(&event->refcount), event)) { | |
4169 | /* leak to avoid use-after-free */ | |
4170 | return; | |
4171 | } | |
0793a61d | 4172 | |
683ede43 | 4173 | _free_event(event); |
0793a61d TG |
4174 | } |
4175 | ||
a66a3052 | 4176 | /* |
f8697762 | 4177 | * Remove user event from the owner task. |
a66a3052 | 4178 | */ |
f8697762 | 4179 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4180 | { |
8882135b | 4181 | struct task_struct *owner; |
fb0459d7 | 4182 | |
8882135b | 4183 | rcu_read_lock(); |
8882135b | 4184 | /* |
f47c02c0 PZ |
4185 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4186 | * observe !owner it means the list deletion is complete and we can | |
4187 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4188 | * owner->perf_event_mutex. |
4189 | */ | |
f47c02c0 | 4190 | owner = lockless_dereference(event->owner); |
8882135b PZ |
4191 | if (owner) { |
4192 | /* | |
4193 | * Since delayed_put_task_struct() also drops the last | |
4194 | * task reference we can safely take a new reference | |
4195 | * while holding the rcu_read_lock(). | |
4196 | */ | |
4197 | get_task_struct(owner); | |
4198 | } | |
4199 | rcu_read_unlock(); | |
4200 | ||
4201 | if (owner) { | |
f63a8daa PZ |
4202 | /* |
4203 | * If we're here through perf_event_exit_task() we're already | |
4204 | * holding ctx->mutex which would be an inversion wrt. the | |
4205 | * normal lock order. | |
4206 | * | |
4207 | * However we can safely take this lock because its the child | |
4208 | * ctx->mutex. | |
4209 | */ | |
4210 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4211 | ||
8882135b PZ |
4212 | /* |
4213 | * We have to re-check the event->owner field, if it is cleared | |
4214 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4215 | * ensured they're done, and we can proceed with freeing the | |
4216 | * event. | |
4217 | */ | |
f47c02c0 | 4218 | if (event->owner) { |
8882135b | 4219 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4220 | smp_store_release(&event->owner, NULL); |
4221 | } | |
8882135b PZ |
4222 | mutex_unlock(&owner->perf_event_mutex); |
4223 | put_task_struct(owner); | |
4224 | } | |
f8697762 JO |
4225 | } |
4226 | ||
f8697762 JO |
4227 | static void put_event(struct perf_event *event) |
4228 | { | |
f8697762 JO |
4229 | if (!atomic_long_dec_and_test(&event->refcount)) |
4230 | return; | |
4231 | ||
c6e5b732 PZ |
4232 | _free_event(event); |
4233 | } | |
4234 | ||
4235 | /* | |
4236 | * Kill an event dead; while event:refcount will preserve the event | |
4237 | * object, it will not preserve its functionality. Once the last 'user' | |
4238 | * gives up the object, we'll destroy the thing. | |
4239 | */ | |
4240 | int perf_event_release_kernel(struct perf_event *event) | |
4241 | { | |
a4f4bb6d | 4242 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4243 | struct perf_event *child, *tmp; |
4244 | ||
a4f4bb6d PZ |
4245 | /* |
4246 | * If we got here through err_file: fput(event_file); we will not have | |
4247 | * attached to a context yet. | |
4248 | */ | |
4249 | if (!ctx) { | |
4250 | WARN_ON_ONCE(event->attach_state & | |
4251 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4252 | goto no_ctx; | |
4253 | } | |
4254 | ||
f8697762 JO |
4255 | if (!is_kernel_event(event)) |
4256 | perf_remove_from_owner(event); | |
8882135b | 4257 | |
5fa7c8ec | 4258 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4259 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4260 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4261 | |
a69b0ca4 | 4262 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4263 | /* |
d8a8cfc7 | 4264 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4265 | * anymore. |
683ede43 | 4266 | * |
a69b0ca4 PZ |
4267 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4268 | * also see this, most importantly inherit_event() which will avoid | |
4269 | * placing more children on the list. | |
683ede43 | 4270 | * |
c6e5b732 PZ |
4271 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4272 | * child events. | |
683ede43 | 4273 | */ |
a69b0ca4 PZ |
4274 | event->state = PERF_EVENT_STATE_DEAD; |
4275 | raw_spin_unlock_irq(&ctx->lock); | |
4276 | ||
4277 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4278 | |
c6e5b732 PZ |
4279 | again: |
4280 | mutex_lock(&event->child_mutex); | |
4281 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4282 | |
c6e5b732 PZ |
4283 | /* |
4284 | * Cannot change, child events are not migrated, see the | |
4285 | * comment with perf_event_ctx_lock_nested(). | |
4286 | */ | |
4287 | ctx = lockless_dereference(child->ctx); | |
4288 | /* | |
4289 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4290 | * through hoops. We start by grabbing a reference on the ctx. | |
4291 | * | |
4292 | * Since the event cannot get freed while we hold the | |
4293 | * child_mutex, the context must also exist and have a !0 | |
4294 | * reference count. | |
4295 | */ | |
4296 | get_ctx(ctx); | |
4297 | ||
4298 | /* | |
4299 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4300 | * acquire ctx::mutex without fear of it going away. Then we | |
4301 | * can re-acquire child_mutex. | |
4302 | */ | |
4303 | mutex_unlock(&event->child_mutex); | |
4304 | mutex_lock(&ctx->mutex); | |
4305 | mutex_lock(&event->child_mutex); | |
4306 | ||
4307 | /* | |
4308 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4309 | * state, if child is still the first entry, it didn't get freed | |
4310 | * and we can continue doing so. | |
4311 | */ | |
4312 | tmp = list_first_entry_or_null(&event->child_list, | |
4313 | struct perf_event, child_list); | |
4314 | if (tmp == child) { | |
4315 | perf_remove_from_context(child, DETACH_GROUP); | |
4316 | list_del(&child->child_list); | |
4317 | free_event(child); | |
4318 | /* | |
4319 | * This matches the refcount bump in inherit_event(); | |
4320 | * this can't be the last reference. | |
4321 | */ | |
4322 | put_event(event); | |
4323 | } | |
4324 | ||
4325 | mutex_unlock(&event->child_mutex); | |
4326 | mutex_unlock(&ctx->mutex); | |
4327 | put_ctx(ctx); | |
4328 | goto again; | |
4329 | } | |
4330 | mutex_unlock(&event->child_mutex); | |
4331 | ||
a4f4bb6d PZ |
4332 | no_ctx: |
4333 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4334 | return 0; |
4335 | } | |
4336 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4337 | ||
8b10c5e2 PZ |
4338 | /* |
4339 | * Called when the last reference to the file is gone. | |
4340 | */ | |
a6fa941d AV |
4341 | static int perf_release(struct inode *inode, struct file *file) |
4342 | { | |
c6e5b732 | 4343 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4344 | return 0; |
fb0459d7 | 4345 | } |
fb0459d7 | 4346 | |
59ed446f | 4347 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4348 | { |
cdd6c482 | 4349 | struct perf_event *child; |
e53c0994 PZ |
4350 | u64 total = 0; |
4351 | ||
59ed446f PZ |
4352 | *enabled = 0; |
4353 | *running = 0; | |
4354 | ||
6f10581a | 4355 | mutex_lock(&event->child_mutex); |
01add3ea | 4356 | |
7d88962e | 4357 | (void)perf_event_read(event, false); |
01add3ea SB |
4358 | total += perf_event_count(event); |
4359 | ||
59ed446f PZ |
4360 | *enabled += event->total_time_enabled + |
4361 | atomic64_read(&event->child_total_time_enabled); | |
4362 | *running += event->total_time_running + | |
4363 | atomic64_read(&event->child_total_time_running); | |
4364 | ||
4365 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4366 | (void)perf_event_read(child, false); |
01add3ea | 4367 | total += perf_event_count(child); |
59ed446f PZ |
4368 | *enabled += child->total_time_enabled; |
4369 | *running += child->total_time_running; | |
4370 | } | |
6f10581a | 4371 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4372 | |
4373 | return total; | |
4374 | } | |
fb0459d7 | 4375 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4376 | |
7d88962e | 4377 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4378 | u64 read_format, u64 *values) |
3dab77fb | 4379 | { |
fa8c2693 PZ |
4380 | struct perf_event *sub; |
4381 | int n = 1; /* skip @nr */ | |
7d88962e | 4382 | int ret; |
f63a8daa | 4383 | |
7d88962e SB |
4384 | ret = perf_event_read(leader, true); |
4385 | if (ret) | |
4386 | return ret; | |
abf4868b | 4387 | |
fa8c2693 PZ |
4388 | /* |
4389 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4390 | * will be identical to those of the leader, so we only publish one | |
4391 | * set. | |
4392 | */ | |
4393 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4394 | values[n++] += leader->total_time_enabled + | |
4395 | atomic64_read(&leader->child_total_time_enabled); | |
4396 | } | |
3dab77fb | 4397 | |
fa8c2693 PZ |
4398 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4399 | values[n++] += leader->total_time_running + | |
4400 | atomic64_read(&leader->child_total_time_running); | |
4401 | } | |
4402 | ||
4403 | /* | |
4404 | * Write {count,id} tuples for every sibling. | |
4405 | */ | |
4406 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4407 | if (read_format & PERF_FORMAT_ID) |
4408 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4409 | |
fa8c2693 PZ |
4410 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4411 | values[n++] += perf_event_count(sub); | |
4412 | if (read_format & PERF_FORMAT_ID) | |
4413 | values[n++] = primary_event_id(sub); | |
4414 | } | |
7d88962e SB |
4415 | |
4416 | return 0; | |
fa8c2693 | 4417 | } |
3dab77fb | 4418 | |
fa8c2693 PZ |
4419 | static int perf_read_group(struct perf_event *event, |
4420 | u64 read_format, char __user *buf) | |
4421 | { | |
4422 | struct perf_event *leader = event->group_leader, *child; | |
4423 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4424 | int ret; |
fa8c2693 | 4425 | u64 *values; |
3dab77fb | 4426 | |
fa8c2693 | 4427 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4428 | |
fa8c2693 PZ |
4429 | values = kzalloc(event->read_size, GFP_KERNEL); |
4430 | if (!values) | |
4431 | return -ENOMEM; | |
3dab77fb | 4432 | |
fa8c2693 PZ |
4433 | values[0] = 1 + leader->nr_siblings; |
4434 | ||
4435 | /* | |
4436 | * By locking the child_mutex of the leader we effectively | |
4437 | * lock the child list of all siblings.. XXX explain how. | |
4438 | */ | |
4439 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4440 | |
7d88962e SB |
4441 | ret = __perf_read_group_add(leader, read_format, values); |
4442 | if (ret) | |
4443 | goto unlock; | |
4444 | ||
4445 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4446 | ret = __perf_read_group_add(child, read_format, values); | |
4447 | if (ret) | |
4448 | goto unlock; | |
4449 | } | |
abf4868b | 4450 | |
fa8c2693 | 4451 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4452 | |
7d88962e | 4453 | ret = event->read_size; |
fa8c2693 PZ |
4454 | if (copy_to_user(buf, values, event->read_size)) |
4455 | ret = -EFAULT; | |
7d88962e | 4456 | goto out; |
fa8c2693 | 4457 | |
7d88962e SB |
4458 | unlock: |
4459 | mutex_unlock(&leader->child_mutex); | |
4460 | out: | |
fa8c2693 | 4461 | kfree(values); |
abf4868b | 4462 | return ret; |
3dab77fb PZ |
4463 | } |
4464 | ||
b15f495b | 4465 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4466 | u64 read_format, char __user *buf) |
4467 | { | |
59ed446f | 4468 | u64 enabled, running; |
3dab77fb PZ |
4469 | u64 values[4]; |
4470 | int n = 0; | |
4471 | ||
59ed446f PZ |
4472 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4473 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4474 | values[n++] = enabled; | |
4475 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4476 | values[n++] = running; | |
3dab77fb | 4477 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4478 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4479 | |
4480 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4481 | return -EFAULT; | |
4482 | ||
4483 | return n * sizeof(u64); | |
4484 | } | |
4485 | ||
dc633982 JO |
4486 | static bool is_event_hup(struct perf_event *event) |
4487 | { | |
4488 | bool no_children; | |
4489 | ||
a69b0ca4 | 4490 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4491 | return false; |
4492 | ||
4493 | mutex_lock(&event->child_mutex); | |
4494 | no_children = list_empty(&event->child_list); | |
4495 | mutex_unlock(&event->child_mutex); | |
4496 | return no_children; | |
4497 | } | |
4498 | ||
0793a61d | 4499 | /* |
cdd6c482 | 4500 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4501 | */ |
4502 | static ssize_t | |
b15f495b | 4503 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4504 | { |
cdd6c482 | 4505 | u64 read_format = event->attr.read_format; |
3dab77fb | 4506 | int ret; |
0793a61d | 4507 | |
3b6f9e5c | 4508 | /* |
cdd6c482 | 4509 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4510 | * error state (i.e. because it was pinned but it couldn't be |
4511 | * scheduled on to the CPU at some point). | |
4512 | */ | |
cdd6c482 | 4513 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4514 | return 0; |
4515 | ||
c320c7b7 | 4516 | if (count < event->read_size) |
3dab77fb PZ |
4517 | return -ENOSPC; |
4518 | ||
cdd6c482 | 4519 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4520 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4521 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4522 | else |
b15f495b | 4523 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4524 | |
3dab77fb | 4525 | return ret; |
0793a61d TG |
4526 | } |
4527 | ||
0793a61d TG |
4528 | static ssize_t |
4529 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4530 | { | |
cdd6c482 | 4531 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4532 | struct perf_event_context *ctx; |
4533 | int ret; | |
0793a61d | 4534 | |
f63a8daa | 4535 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4536 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4537 | perf_event_ctx_unlock(event, ctx); |
4538 | ||
4539 | return ret; | |
0793a61d TG |
4540 | } |
4541 | ||
4542 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4543 | { | |
cdd6c482 | 4544 | struct perf_event *event = file->private_data; |
76369139 | 4545 | struct ring_buffer *rb; |
61b67684 | 4546 | unsigned int events = POLLHUP; |
c7138f37 | 4547 | |
e708d7ad | 4548 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4549 | |
dc633982 | 4550 | if (is_event_hup(event)) |
179033b3 | 4551 | return events; |
c7138f37 | 4552 | |
10c6db11 | 4553 | /* |
9bb5d40c PZ |
4554 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4555 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4556 | */ |
4557 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4558 | rb = event->rb; |
4559 | if (rb) | |
76369139 | 4560 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4561 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4562 | return events; |
4563 | } | |
4564 | ||
f63a8daa | 4565 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4566 | { |
7d88962e | 4567 | (void)perf_event_read(event, false); |
e7850595 | 4568 | local64_set(&event->count, 0); |
cdd6c482 | 4569 | perf_event_update_userpage(event); |
3df5edad PZ |
4570 | } |
4571 | ||
c93f7669 | 4572 | /* |
cdd6c482 IM |
4573 | * Holding the top-level event's child_mutex means that any |
4574 | * descendant process that has inherited this event will block | |
8ba289b8 | 4575 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4576 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4577 | */ |
cdd6c482 IM |
4578 | static void perf_event_for_each_child(struct perf_event *event, |
4579 | void (*func)(struct perf_event *)) | |
3df5edad | 4580 | { |
cdd6c482 | 4581 | struct perf_event *child; |
3df5edad | 4582 | |
cdd6c482 | 4583 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4584 | |
cdd6c482 IM |
4585 | mutex_lock(&event->child_mutex); |
4586 | func(event); | |
4587 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4588 | func(child); |
cdd6c482 | 4589 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4590 | } |
4591 | ||
cdd6c482 IM |
4592 | static void perf_event_for_each(struct perf_event *event, |
4593 | void (*func)(struct perf_event *)) | |
3df5edad | 4594 | { |
cdd6c482 IM |
4595 | struct perf_event_context *ctx = event->ctx; |
4596 | struct perf_event *sibling; | |
3df5edad | 4597 | |
f63a8daa PZ |
4598 | lockdep_assert_held(&ctx->mutex); |
4599 | ||
cdd6c482 | 4600 | event = event->group_leader; |
75f937f2 | 4601 | |
cdd6c482 | 4602 | perf_event_for_each_child(event, func); |
cdd6c482 | 4603 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4604 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4605 | } |
4606 | ||
fae3fde6 PZ |
4607 | static void __perf_event_period(struct perf_event *event, |
4608 | struct perf_cpu_context *cpuctx, | |
4609 | struct perf_event_context *ctx, | |
4610 | void *info) | |
c7999c6f | 4611 | { |
fae3fde6 | 4612 | u64 value = *((u64 *)info); |
c7999c6f | 4613 | bool active; |
08247e31 | 4614 | |
cdd6c482 | 4615 | if (event->attr.freq) { |
cdd6c482 | 4616 | event->attr.sample_freq = value; |
08247e31 | 4617 | } else { |
cdd6c482 IM |
4618 | event->attr.sample_period = value; |
4619 | event->hw.sample_period = value; | |
08247e31 | 4620 | } |
bad7192b PZ |
4621 | |
4622 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4623 | if (active) { | |
4624 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4625 | /* |
4626 | * We could be throttled; unthrottle now to avoid the tick | |
4627 | * trying to unthrottle while we already re-started the event. | |
4628 | */ | |
4629 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4630 | event->hw.interrupts = 0; | |
4631 | perf_log_throttle(event, 1); | |
4632 | } | |
bad7192b PZ |
4633 | event->pmu->stop(event, PERF_EF_UPDATE); |
4634 | } | |
4635 | ||
4636 | local64_set(&event->hw.period_left, 0); | |
4637 | ||
4638 | if (active) { | |
4639 | event->pmu->start(event, PERF_EF_RELOAD); | |
4640 | perf_pmu_enable(ctx->pmu); | |
4641 | } | |
c7999c6f PZ |
4642 | } |
4643 | ||
4644 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4645 | { | |
c7999c6f PZ |
4646 | u64 value; |
4647 | ||
4648 | if (!is_sampling_event(event)) | |
4649 | return -EINVAL; | |
4650 | ||
4651 | if (copy_from_user(&value, arg, sizeof(value))) | |
4652 | return -EFAULT; | |
4653 | ||
4654 | if (!value) | |
4655 | return -EINVAL; | |
4656 | ||
4657 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4658 | return -EINVAL; | |
4659 | ||
fae3fde6 | 4660 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4661 | |
c7999c6f | 4662 | return 0; |
08247e31 PZ |
4663 | } |
4664 | ||
ac9721f3 PZ |
4665 | static const struct file_operations perf_fops; |
4666 | ||
2903ff01 | 4667 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4668 | { |
2903ff01 AV |
4669 | struct fd f = fdget(fd); |
4670 | if (!f.file) | |
4671 | return -EBADF; | |
ac9721f3 | 4672 | |
2903ff01 AV |
4673 | if (f.file->f_op != &perf_fops) { |
4674 | fdput(f); | |
4675 | return -EBADF; | |
ac9721f3 | 4676 | } |
2903ff01 AV |
4677 | *p = f; |
4678 | return 0; | |
ac9721f3 PZ |
4679 | } |
4680 | ||
4681 | static int perf_event_set_output(struct perf_event *event, | |
4682 | struct perf_event *output_event); | |
6fb2915d | 4683 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4684 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4685 | |
f63a8daa | 4686 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4687 | { |
cdd6c482 | 4688 | void (*func)(struct perf_event *); |
3df5edad | 4689 | u32 flags = arg; |
d859e29f PM |
4690 | |
4691 | switch (cmd) { | |
cdd6c482 | 4692 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4693 | func = _perf_event_enable; |
d859e29f | 4694 | break; |
cdd6c482 | 4695 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4696 | func = _perf_event_disable; |
79f14641 | 4697 | break; |
cdd6c482 | 4698 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4699 | func = _perf_event_reset; |
6de6a7b9 | 4700 | break; |
3df5edad | 4701 | |
cdd6c482 | 4702 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4703 | return _perf_event_refresh(event, arg); |
08247e31 | 4704 | |
cdd6c482 IM |
4705 | case PERF_EVENT_IOC_PERIOD: |
4706 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4707 | |
cf4957f1 JO |
4708 | case PERF_EVENT_IOC_ID: |
4709 | { | |
4710 | u64 id = primary_event_id(event); | |
4711 | ||
4712 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4713 | return -EFAULT; | |
4714 | return 0; | |
4715 | } | |
4716 | ||
cdd6c482 | 4717 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4718 | { |
ac9721f3 | 4719 | int ret; |
ac9721f3 | 4720 | if (arg != -1) { |
2903ff01 AV |
4721 | struct perf_event *output_event; |
4722 | struct fd output; | |
4723 | ret = perf_fget_light(arg, &output); | |
4724 | if (ret) | |
4725 | return ret; | |
4726 | output_event = output.file->private_data; | |
4727 | ret = perf_event_set_output(event, output_event); | |
4728 | fdput(output); | |
4729 | } else { | |
4730 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4731 | } |
ac9721f3 PZ |
4732 | return ret; |
4733 | } | |
a4be7c27 | 4734 | |
6fb2915d LZ |
4735 | case PERF_EVENT_IOC_SET_FILTER: |
4736 | return perf_event_set_filter(event, (void __user *)arg); | |
4737 | ||
2541517c AS |
4738 | case PERF_EVENT_IOC_SET_BPF: |
4739 | return perf_event_set_bpf_prog(event, arg); | |
4740 | ||
86e7972f WN |
4741 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4742 | struct ring_buffer *rb; | |
4743 | ||
4744 | rcu_read_lock(); | |
4745 | rb = rcu_dereference(event->rb); | |
4746 | if (!rb || !rb->nr_pages) { | |
4747 | rcu_read_unlock(); | |
4748 | return -EINVAL; | |
4749 | } | |
4750 | rb_toggle_paused(rb, !!arg); | |
4751 | rcu_read_unlock(); | |
4752 | return 0; | |
4753 | } | |
d859e29f | 4754 | default: |
3df5edad | 4755 | return -ENOTTY; |
d859e29f | 4756 | } |
3df5edad PZ |
4757 | |
4758 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4759 | perf_event_for_each(event, func); |
3df5edad | 4760 | else |
cdd6c482 | 4761 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4762 | |
4763 | return 0; | |
d859e29f PM |
4764 | } |
4765 | ||
f63a8daa PZ |
4766 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4767 | { | |
4768 | struct perf_event *event = file->private_data; | |
4769 | struct perf_event_context *ctx; | |
4770 | long ret; | |
4771 | ||
4772 | ctx = perf_event_ctx_lock(event); | |
4773 | ret = _perf_ioctl(event, cmd, arg); | |
4774 | perf_event_ctx_unlock(event, ctx); | |
4775 | ||
4776 | return ret; | |
4777 | } | |
4778 | ||
b3f20785 PM |
4779 | #ifdef CONFIG_COMPAT |
4780 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4781 | unsigned long arg) | |
4782 | { | |
4783 | switch (_IOC_NR(cmd)) { | |
4784 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4785 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4786 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4787 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4788 | cmd &= ~IOCSIZE_MASK; | |
4789 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4790 | } | |
4791 | break; | |
4792 | } | |
4793 | return perf_ioctl(file, cmd, arg); | |
4794 | } | |
4795 | #else | |
4796 | # define perf_compat_ioctl NULL | |
4797 | #endif | |
4798 | ||
cdd6c482 | 4799 | int perf_event_task_enable(void) |
771d7cde | 4800 | { |
f63a8daa | 4801 | struct perf_event_context *ctx; |
cdd6c482 | 4802 | struct perf_event *event; |
771d7cde | 4803 | |
cdd6c482 | 4804 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4805 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4806 | ctx = perf_event_ctx_lock(event); | |
4807 | perf_event_for_each_child(event, _perf_event_enable); | |
4808 | perf_event_ctx_unlock(event, ctx); | |
4809 | } | |
cdd6c482 | 4810 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4811 | |
4812 | return 0; | |
4813 | } | |
4814 | ||
cdd6c482 | 4815 | int perf_event_task_disable(void) |
771d7cde | 4816 | { |
f63a8daa | 4817 | struct perf_event_context *ctx; |
cdd6c482 | 4818 | struct perf_event *event; |
771d7cde | 4819 | |
cdd6c482 | 4820 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4821 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4822 | ctx = perf_event_ctx_lock(event); | |
4823 | perf_event_for_each_child(event, _perf_event_disable); | |
4824 | perf_event_ctx_unlock(event, ctx); | |
4825 | } | |
cdd6c482 | 4826 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4827 | |
4828 | return 0; | |
4829 | } | |
4830 | ||
cdd6c482 | 4831 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4832 | { |
a4eaf7f1 PZ |
4833 | if (event->hw.state & PERF_HES_STOPPED) |
4834 | return 0; | |
4835 | ||
cdd6c482 | 4836 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4837 | return 0; |
4838 | ||
35edc2a5 | 4839 | return event->pmu->event_idx(event); |
194002b2 PZ |
4840 | } |
4841 | ||
c4794295 | 4842 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4843 | u64 *now, |
7f310a5d EM |
4844 | u64 *enabled, |
4845 | u64 *running) | |
c4794295 | 4846 | { |
e3f3541c | 4847 | u64 ctx_time; |
c4794295 | 4848 | |
e3f3541c PZ |
4849 | *now = perf_clock(); |
4850 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4851 | *enabled = ctx_time - event->tstamp_enabled; |
4852 | *running = ctx_time - event->tstamp_running; | |
4853 | } | |
4854 | ||
fa731587 PZ |
4855 | static void perf_event_init_userpage(struct perf_event *event) |
4856 | { | |
4857 | struct perf_event_mmap_page *userpg; | |
4858 | struct ring_buffer *rb; | |
4859 | ||
4860 | rcu_read_lock(); | |
4861 | rb = rcu_dereference(event->rb); | |
4862 | if (!rb) | |
4863 | goto unlock; | |
4864 | ||
4865 | userpg = rb->user_page; | |
4866 | ||
4867 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4868 | userpg->cap_bit0_is_deprecated = 1; | |
4869 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4870 | userpg->data_offset = PAGE_SIZE; |
4871 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4872 | |
4873 | unlock: | |
4874 | rcu_read_unlock(); | |
4875 | } | |
4876 | ||
c1317ec2 AL |
4877 | void __weak arch_perf_update_userpage( |
4878 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4879 | { |
4880 | } | |
4881 | ||
38ff667b PZ |
4882 | /* |
4883 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4884 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4885 | * code calls this from NMI context. | |
4886 | */ | |
cdd6c482 | 4887 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4888 | { |
cdd6c482 | 4889 | struct perf_event_mmap_page *userpg; |
76369139 | 4890 | struct ring_buffer *rb; |
e3f3541c | 4891 | u64 enabled, running, now; |
38ff667b PZ |
4892 | |
4893 | rcu_read_lock(); | |
5ec4c599 PZ |
4894 | rb = rcu_dereference(event->rb); |
4895 | if (!rb) | |
4896 | goto unlock; | |
4897 | ||
0d641208 EM |
4898 | /* |
4899 | * compute total_time_enabled, total_time_running | |
4900 | * based on snapshot values taken when the event | |
4901 | * was last scheduled in. | |
4902 | * | |
4903 | * we cannot simply called update_context_time() | |
4904 | * because of locking issue as we can be called in | |
4905 | * NMI context | |
4906 | */ | |
e3f3541c | 4907 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4908 | |
76369139 | 4909 | userpg = rb->user_page; |
7b732a75 PZ |
4910 | /* |
4911 | * Disable preemption so as to not let the corresponding user-space | |
4912 | * spin too long if we get preempted. | |
4913 | */ | |
4914 | preempt_disable(); | |
37d81828 | 4915 | ++userpg->lock; |
92f22a38 | 4916 | barrier(); |
cdd6c482 | 4917 | userpg->index = perf_event_index(event); |
b5e58793 | 4918 | userpg->offset = perf_event_count(event); |
365a4038 | 4919 | if (userpg->index) |
e7850595 | 4920 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4921 | |
0d641208 | 4922 | userpg->time_enabled = enabled + |
cdd6c482 | 4923 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4924 | |
0d641208 | 4925 | userpg->time_running = running + |
cdd6c482 | 4926 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4927 | |
c1317ec2 | 4928 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4929 | |
92f22a38 | 4930 | barrier(); |
37d81828 | 4931 | ++userpg->lock; |
7b732a75 | 4932 | preempt_enable(); |
38ff667b | 4933 | unlock: |
7b732a75 | 4934 | rcu_read_unlock(); |
37d81828 PM |
4935 | } |
4936 | ||
11bac800 | 4937 | static int perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 4938 | { |
11bac800 | 4939 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 4940 | struct ring_buffer *rb; |
906010b2 PZ |
4941 | int ret = VM_FAULT_SIGBUS; |
4942 | ||
4943 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4944 | if (vmf->pgoff == 0) | |
4945 | ret = 0; | |
4946 | return ret; | |
4947 | } | |
4948 | ||
4949 | rcu_read_lock(); | |
76369139 FW |
4950 | rb = rcu_dereference(event->rb); |
4951 | if (!rb) | |
906010b2 PZ |
4952 | goto unlock; |
4953 | ||
4954 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4955 | goto unlock; | |
4956 | ||
76369139 | 4957 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4958 | if (!vmf->page) |
4959 | goto unlock; | |
4960 | ||
4961 | get_page(vmf->page); | |
11bac800 | 4962 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
4963 | vmf->page->index = vmf->pgoff; |
4964 | ||
4965 | ret = 0; | |
4966 | unlock: | |
4967 | rcu_read_unlock(); | |
4968 | ||
4969 | return ret; | |
4970 | } | |
4971 | ||
10c6db11 PZ |
4972 | static void ring_buffer_attach(struct perf_event *event, |
4973 | struct ring_buffer *rb) | |
4974 | { | |
b69cf536 | 4975 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4976 | unsigned long flags; |
4977 | ||
b69cf536 PZ |
4978 | if (event->rb) { |
4979 | /* | |
4980 | * Should be impossible, we set this when removing | |
4981 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4982 | */ | |
4983 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4984 | |
b69cf536 | 4985 | old_rb = event->rb; |
b69cf536 PZ |
4986 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4987 | list_del_rcu(&event->rb_entry); | |
4988 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4989 | |
2f993cf0 ON |
4990 | event->rcu_batches = get_state_synchronize_rcu(); |
4991 | event->rcu_pending = 1; | |
b69cf536 | 4992 | } |
10c6db11 | 4993 | |
b69cf536 | 4994 | if (rb) { |
2f993cf0 ON |
4995 | if (event->rcu_pending) { |
4996 | cond_synchronize_rcu(event->rcu_batches); | |
4997 | event->rcu_pending = 0; | |
4998 | } | |
4999 | ||
b69cf536 PZ |
5000 | spin_lock_irqsave(&rb->event_lock, flags); |
5001 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5002 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5003 | } | |
5004 | ||
767ae086 AS |
5005 | /* |
5006 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5007 | * before swizzling the event::rb pointer; if it's getting | |
5008 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5009 | * restart. See the comment in __perf_pmu_output_stop(). | |
5010 | * | |
5011 | * Data will inevitably be lost when set_output is done in | |
5012 | * mid-air, but then again, whoever does it like this is | |
5013 | * not in for the data anyway. | |
5014 | */ | |
5015 | if (has_aux(event)) | |
5016 | perf_event_stop(event, 0); | |
5017 | ||
b69cf536 PZ |
5018 | rcu_assign_pointer(event->rb, rb); |
5019 | ||
5020 | if (old_rb) { | |
5021 | ring_buffer_put(old_rb); | |
5022 | /* | |
5023 | * Since we detached before setting the new rb, so that we | |
5024 | * could attach the new rb, we could have missed a wakeup. | |
5025 | * Provide it now. | |
5026 | */ | |
5027 | wake_up_all(&event->waitq); | |
5028 | } | |
10c6db11 PZ |
5029 | } |
5030 | ||
5031 | static void ring_buffer_wakeup(struct perf_event *event) | |
5032 | { | |
5033 | struct ring_buffer *rb; | |
5034 | ||
5035 | rcu_read_lock(); | |
5036 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5037 | if (rb) { |
5038 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5039 | wake_up_all(&event->waitq); | |
5040 | } | |
10c6db11 PZ |
5041 | rcu_read_unlock(); |
5042 | } | |
5043 | ||
fdc26706 | 5044 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5045 | { |
76369139 | 5046 | struct ring_buffer *rb; |
7b732a75 | 5047 | |
ac9721f3 | 5048 | rcu_read_lock(); |
76369139 FW |
5049 | rb = rcu_dereference(event->rb); |
5050 | if (rb) { | |
5051 | if (!atomic_inc_not_zero(&rb->refcount)) | |
5052 | rb = NULL; | |
ac9721f3 PZ |
5053 | } |
5054 | rcu_read_unlock(); | |
5055 | ||
76369139 | 5056 | return rb; |
ac9721f3 PZ |
5057 | } |
5058 | ||
fdc26706 | 5059 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5060 | { |
76369139 | 5061 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 5062 | return; |
7b732a75 | 5063 | |
9bb5d40c | 5064 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5065 | |
76369139 | 5066 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5067 | } |
5068 | ||
5069 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5070 | { | |
cdd6c482 | 5071 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5072 | |
cdd6c482 | 5073 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5074 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5075 | |
45bfb2e5 PZ |
5076 | if (vma->vm_pgoff) |
5077 | atomic_inc(&event->rb->aux_mmap_count); | |
5078 | ||
1e0fb9ec AL |
5079 | if (event->pmu->event_mapped) |
5080 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
5081 | } |
5082 | ||
95ff4ca2 AS |
5083 | static void perf_pmu_output_stop(struct perf_event *event); |
5084 | ||
9bb5d40c PZ |
5085 | /* |
5086 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5087 | * event, or through other events by use of perf_event_set_output(). | |
5088 | * | |
5089 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5090 | * the buffer here, where we still have a VM context. This means we need | |
5091 | * to detach all events redirecting to us. | |
5092 | */ | |
7b732a75 PZ |
5093 | static void perf_mmap_close(struct vm_area_struct *vma) |
5094 | { | |
cdd6c482 | 5095 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5096 | |
b69cf536 | 5097 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5098 | struct user_struct *mmap_user = rb->mmap_user; |
5099 | int mmap_locked = rb->mmap_locked; | |
5100 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5101 | |
1e0fb9ec AL |
5102 | if (event->pmu->event_unmapped) |
5103 | event->pmu->event_unmapped(event); | |
5104 | ||
45bfb2e5 PZ |
5105 | /* |
5106 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5107 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5108 | * serialize with perf_mmap here. | |
5109 | */ | |
5110 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5111 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5112 | /* |
5113 | * Stop all AUX events that are writing to this buffer, | |
5114 | * so that we can free its AUX pages and corresponding PMU | |
5115 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5116 | * they won't start any more (see perf_aux_output_begin()). | |
5117 | */ | |
5118 | perf_pmu_output_stop(event); | |
5119 | ||
5120 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5121 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5122 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5123 | ||
95ff4ca2 | 5124 | /* this has to be the last one */ |
45bfb2e5 | 5125 | rb_free_aux(rb); |
95ff4ca2 AS |
5126 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5127 | ||
45bfb2e5 PZ |
5128 | mutex_unlock(&event->mmap_mutex); |
5129 | } | |
5130 | ||
9bb5d40c PZ |
5131 | atomic_dec(&rb->mmap_count); |
5132 | ||
5133 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5134 | goto out_put; |
9bb5d40c | 5135 | |
b69cf536 | 5136 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5137 | mutex_unlock(&event->mmap_mutex); |
5138 | ||
5139 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5140 | if (atomic_read(&rb->mmap_count)) |
5141 | goto out_put; | |
ac9721f3 | 5142 | |
9bb5d40c PZ |
5143 | /* |
5144 | * No other mmap()s, detach from all other events that might redirect | |
5145 | * into the now unreachable buffer. Somewhat complicated by the | |
5146 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5147 | */ | |
5148 | again: | |
5149 | rcu_read_lock(); | |
5150 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5151 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5152 | /* | |
5153 | * This event is en-route to free_event() which will | |
5154 | * detach it and remove it from the list. | |
5155 | */ | |
5156 | continue; | |
5157 | } | |
5158 | rcu_read_unlock(); | |
789f90fc | 5159 | |
9bb5d40c PZ |
5160 | mutex_lock(&event->mmap_mutex); |
5161 | /* | |
5162 | * Check we didn't race with perf_event_set_output() which can | |
5163 | * swizzle the rb from under us while we were waiting to | |
5164 | * acquire mmap_mutex. | |
5165 | * | |
5166 | * If we find a different rb; ignore this event, a next | |
5167 | * iteration will no longer find it on the list. We have to | |
5168 | * still restart the iteration to make sure we're not now | |
5169 | * iterating the wrong list. | |
5170 | */ | |
b69cf536 PZ |
5171 | if (event->rb == rb) |
5172 | ring_buffer_attach(event, NULL); | |
5173 | ||
cdd6c482 | 5174 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5175 | put_event(event); |
ac9721f3 | 5176 | |
9bb5d40c PZ |
5177 | /* |
5178 | * Restart the iteration; either we're on the wrong list or | |
5179 | * destroyed its integrity by doing a deletion. | |
5180 | */ | |
5181 | goto again; | |
7b732a75 | 5182 | } |
9bb5d40c PZ |
5183 | rcu_read_unlock(); |
5184 | ||
5185 | /* | |
5186 | * It could be there's still a few 0-ref events on the list; they'll | |
5187 | * get cleaned up by free_event() -- they'll also still have their | |
5188 | * ref on the rb and will free it whenever they are done with it. | |
5189 | * | |
5190 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5191 | * undo the VM accounting. | |
5192 | */ | |
5193 | ||
5194 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5195 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5196 | free_uid(mmap_user); | |
5197 | ||
b69cf536 | 5198 | out_put: |
9bb5d40c | 5199 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5200 | } |
5201 | ||
f0f37e2f | 5202 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5203 | .open = perf_mmap_open, |
45bfb2e5 | 5204 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5205 | .fault = perf_mmap_fault, |
5206 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5207 | }; |
5208 | ||
5209 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5210 | { | |
cdd6c482 | 5211 | struct perf_event *event = file->private_data; |
22a4f650 | 5212 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5213 | struct user_struct *user = current_user(); |
22a4f650 | 5214 | unsigned long locked, lock_limit; |
45bfb2e5 | 5215 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5216 | unsigned long vma_size; |
5217 | unsigned long nr_pages; | |
45bfb2e5 | 5218 | long user_extra = 0, extra = 0; |
d57e34fd | 5219 | int ret = 0, flags = 0; |
37d81828 | 5220 | |
c7920614 PZ |
5221 | /* |
5222 | * Don't allow mmap() of inherited per-task counters. This would | |
5223 | * create a performance issue due to all children writing to the | |
76369139 | 5224 | * same rb. |
c7920614 PZ |
5225 | */ |
5226 | if (event->cpu == -1 && event->attr.inherit) | |
5227 | return -EINVAL; | |
5228 | ||
43a21ea8 | 5229 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5230 | return -EINVAL; |
7b732a75 PZ |
5231 | |
5232 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5233 | |
5234 | if (vma->vm_pgoff == 0) { | |
5235 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5236 | } else { | |
5237 | /* | |
5238 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5239 | * mapped, all subsequent mappings should have the same size | |
5240 | * and offset. Must be above the normal perf buffer. | |
5241 | */ | |
5242 | u64 aux_offset, aux_size; | |
5243 | ||
5244 | if (!event->rb) | |
5245 | return -EINVAL; | |
5246 | ||
5247 | nr_pages = vma_size / PAGE_SIZE; | |
5248 | ||
5249 | mutex_lock(&event->mmap_mutex); | |
5250 | ret = -EINVAL; | |
5251 | ||
5252 | rb = event->rb; | |
5253 | if (!rb) | |
5254 | goto aux_unlock; | |
5255 | ||
5256 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5257 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5258 | ||
5259 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5260 | goto aux_unlock; | |
5261 | ||
5262 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5263 | goto aux_unlock; | |
5264 | ||
5265 | /* already mapped with a different offset */ | |
5266 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5267 | goto aux_unlock; | |
5268 | ||
5269 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5270 | goto aux_unlock; | |
5271 | ||
5272 | /* already mapped with a different size */ | |
5273 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5274 | goto aux_unlock; | |
5275 | ||
5276 | if (!is_power_of_2(nr_pages)) | |
5277 | goto aux_unlock; | |
5278 | ||
5279 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5280 | goto aux_unlock; | |
5281 | ||
5282 | if (rb_has_aux(rb)) { | |
5283 | atomic_inc(&rb->aux_mmap_count); | |
5284 | ret = 0; | |
5285 | goto unlock; | |
5286 | } | |
5287 | ||
5288 | atomic_set(&rb->aux_mmap_count, 1); | |
5289 | user_extra = nr_pages; | |
5290 | ||
5291 | goto accounting; | |
5292 | } | |
7b732a75 | 5293 | |
7730d865 | 5294 | /* |
76369139 | 5295 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5296 | * can do bitmasks instead of modulo. |
5297 | */ | |
2ed11312 | 5298 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5299 | return -EINVAL; |
5300 | ||
7b732a75 | 5301 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5302 | return -EINVAL; |
5303 | ||
cdd6c482 | 5304 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5305 | again: |
cdd6c482 | 5306 | mutex_lock(&event->mmap_mutex); |
76369139 | 5307 | if (event->rb) { |
9bb5d40c | 5308 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5309 | ret = -EINVAL; |
9bb5d40c PZ |
5310 | goto unlock; |
5311 | } | |
5312 | ||
5313 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5314 | /* | |
5315 | * Raced against perf_mmap_close() through | |
5316 | * perf_event_set_output(). Try again, hope for better | |
5317 | * luck. | |
5318 | */ | |
5319 | mutex_unlock(&event->mmap_mutex); | |
5320 | goto again; | |
5321 | } | |
5322 | ||
ebb3c4c4 PZ |
5323 | goto unlock; |
5324 | } | |
5325 | ||
789f90fc | 5326 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5327 | |
5328 | accounting: | |
cdd6c482 | 5329 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5330 | |
5331 | /* | |
5332 | * Increase the limit linearly with more CPUs: | |
5333 | */ | |
5334 | user_lock_limit *= num_online_cpus(); | |
5335 | ||
789f90fc | 5336 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5337 | |
789f90fc PZ |
5338 | if (user_locked > user_lock_limit) |
5339 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5340 | |
78d7d407 | 5341 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5342 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5343 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5344 | |
459ec28a IM |
5345 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5346 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5347 | ret = -EPERM; |
5348 | goto unlock; | |
5349 | } | |
7b732a75 | 5350 | |
45bfb2e5 | 5351 | WARN_ON(!rb && event->rb); |
906010b2 | 5352 | |
d57e34fd | 5353 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5354 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5355 | |
76369139 | 5356 | if (!rb) { |
45bfb2e5 PZ |
5357 | rb = rb_alloc(nr_pages, |
5358 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5359 | event->cpu, flags); | |
26cb63ad | 5360 | |
45bfb2e5 PZ |
5361 | if (!rb) { |
5362 | ret = -ENOMEM; | |
5363 | goto unlock; | |
5364 | } | |
43a21ea8 | 5365 | |
45bfb2e5 PZ |
5366 | atomic_set(&rb->mmap_count, 1); |
5367 | rb->mmap_user = get_current_user(); | |
5368 | rb->mmap_locked = extra; | |
26cb63ad | 5369 | |
45bfb2e5 | 5370 | ring_buffer_attach(event, rb); |
ac9721f3 | 5371 | |
45bfb2e5 PZ |
5372 | perf_event_init_userpage(event); |
5373 | perf_event_update_userpage(event); | |
5374 | } else { | |
1a594131 AS |
5375 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5376 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5377 | if (!ret) |
5378 | rb->aux_mmap_locked = extra; | |
5379 | } | |
9a0f05cb | 5380 | |
ebb3c4c4 | 5381 | unlock: |
45bfb2e5 PZ |
5382 | if (!ret) { |
5383 | atomic_long_add(user_extra, &user->locked_vm); | |
5384 | vma->vm_mm->pinned_vm += extra; | |
5385 | ||
ac9721f3 | 5386 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5387 | } else if (rb) { |
5388 | atomic_dec(&rb->mmap_count); | |
5389 | } | |
5390 | aux_unlock: | |
cdd6c482 | 5391 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5392 | |
9bb5d40c PZ |
5393 | /* |
5394 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5395 | * vma. | |
5396 | */ | |
26cb63ad | 5397 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5398 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5399 | |
1e0fb9ec AL |
5400 | if (event->pmu->event_mapped) |
5401 | event->pmu->event_mapped(event); | |
5402 | ||
7b732a75 | 5403 | return ret; |
37d81828 PM |
5404 | } |
5405 | ||
3c446b3d PZ |
5406 | static int perf_fasync(int fd, struct file *filp, int on) |
5407 | { | |
496ad9aa | 5408 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5409 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5410 | int retval; |
5411 | ||
5955102c | 5412 | inode_lock(inode); |
cdd6c482 | 5413 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5414 | inode_unlock(inode); |
3c446b3d PZ |
5415 | |
5416 | if (retval < 0) | |
5417 | return retval; | |
5418 | ||
5419 | return 0; | |
5420 | } | |
5421 | ||
0793a61d | 5422 | static const struct file_operations perf_fops = { |
3326c1ce | 5423 | .llseek = no_llseek, |
0793a61d TG |
5424 | .release = perf_release, |
5425 | .read = perf_read, | |
5426 | .poll = perf_poll, | |
d859e29f | 5427 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5428 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5429 | .mmap = perf_mmap, |
3c446b3d | 5430 | .fasync = perf_fasync, |
0793a61d TG |
5431 | }; |
5432 | ||
925d519a | 5433 | /* |
cdd6c482 | 5434 | * Perf event wakeup |
925d519a PZ |
5435 | * |
5436 | * If there's data, ensure we set the poll() state and publish everything | |
5437 | * to user-space before waking everybody up. | |
5438 | */ | |
5439 | ||
fed66e2c PZ |
5440 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5441 | { | |
5442 | /* only the parent has fasync state */ | |
5443 | if (event->parent) | |
5444 | event = event->parent; | |
5445 | return &event->fasync; | |
5446 | } | |
5447 | ||
cdd6c482 | 5448 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5449 | { |
10c6db11 | 5450 | ring_buffer_wakeup(event); |
4c9e2542 | 5451 | |
cdd6c482 | 5452 | if (event->pending_kill) { |
fed66e2c | 5453 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5454 | event->pending_kill = 0; |
4c9e2542 | 5455 | } |
925d519a PZ |
5456 | } |
5457 | ||
e360adbe | 5458 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5459 | { |
cdd6c482 IM |
5460 | struct perf_event *event = container_of(entry, |
5461 | struct perf_event, pending); | |
d525211f PZ |
5462 | int rctx; |
5463 | ||
5464 | rctx = perf_swevent_get_recursion_context(); | |
5465 | /* | |
5466 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5467 | * and we won't recurse 'further'. | |
5468 | */ | |
79f14641 | 5469 | |
cdd6c482 IM |
5470 | if (event->pending_disable) { |
5471 | event->pending_disable = 0; | |
fae3fde6 | 5472 | perf_event_disable_local(event); |
79f14641 PZ |
5473 | } |
5474 | ||
cdd6c482 IM |
5475 | if (event->pending_wakeup) { |
5476 | event->pending_wakeup = 0; | |
5477 | perf_event_wakeup(event); | |
79f14641 | 5478 | } |
d525211f PZ |
5479 | |
5480 | if (rctx >= 0) | |
5481 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5482 | } |
5483 | ||
39447b38 ZY |
5484 | /* |
5485 | * We assume there is only KVM supporting the callbacks. | |
5486 | * Later on, we might change it to a list if there is | |
5487 | * another virtualization implementation supporting the callbacks. | |
5488 | */ | |
5489 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5490 | ||
5491 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5492 | { | |
5493 | perf_guest_cbs = cbs; | |
5494 | return 0; | |
5495 | } | |
5496 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5497 | ||
5498 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5499 | { | |
5500 | perf_guest_cbs = NULL; | |
5501 | return 0; | |
5502 | } | |
5503 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5504 | ||
4018994f JO |
5505 | static void |
5506 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5507 | struct pt_regs *regs, u64 mask) | |
5508 | { | |
5509 | int bit; | |
29dd3288 | 5510 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5511 | |
29dd3288 MS |
5512 | bitmap_from_u64(_mask, mask); |
5513 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5514 | u64 val; |
5515 | ||
5516 | val = perf_reg_value(regs, bit); | |
5517 | perf_output_put(handle, val); | |
5518 | } | |
5519 | } | |
5520 | ||
60e2364e | 5521 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5522 | struct pt_regs *regs, |
5523 | struct pt_regs *regs_user_copy) | |
4018994f | 5524 | { |
88a7c26a AL |
5525 | if (user_mode(regs)) { |
5526 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5527 | regs_user->regs = regs; |
88a7c26a AL |
5528 | } else if (current->mm) { |
5529 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5530 | } else { |
5531 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5532 | regs_user->regs = NULL; | |
4018994f JO |
5533 | } |
5534 | } | |
5535 | ||
60e2364e SE |
5536 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5537 | struct pt_regs *regs) | |
5538 | { | |
5539 | regs_intr->regs = regs; | |
5540 | regs_intr->abi = perf_reg_abi(current); | |
5541 | } | |
5542 | ||
5543 | ||
c5ebcedb JO |
5544 | /* |
5545 | * Get remaining task size from user stack pointer. | |
5546 | * | |
5547 | * It'd be better to take stack vma map and limit this more | |
5548 | * precisly, but there's no way to get it safely under interrupt, | |
5549 | * so using TASK_SIZE as limit. | |
5550 | */ | |
5551 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5552 | { | |
5553 | unsigned long addr = perf_user_stack_pointer(regs); | |
5554 | ||
5555 | if (!addr || addr >= TASK_SIZE) | |
5556 | return 0; | |
5557 | ||
5558 | return TASK_SIZE - addr; | |
5559 | } | |
5560 | ||
5561 | static u16 | |
5562 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5563 | struct pt_regs *regs) | |
5564 | { | |
5565 | u64 task_size; | |
5566 | ||
5567 | /* No regs, no stack pointer, no dump. */ | |
5568 | if (!regs) | |
5569 | return 0; | |
5570 | ||
5571 | /* | |
5572 | * Check if we fit in with the requested stack size into the: | |
5573 | * - TASK_SIZE | |
5574 | * If we don't, we limit the size to the TASK_SIZE. | |
5575 | * | |
5576 | * - remaining sample size | |
5577 | * If we don't, we customize the stack size to | |
5578 | * fit in to the remaining sample size. | |
5579 | */ | |
5580 | ||
5581 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5582 | stack_size = min(stack_size, (u16) task_size); | |
5583 | ||
5584 | /* Current header size plus static size and dynamic size. */ | |
5585 | header_size += 2 * sizeof(u64); | |
5586 | ||
5587 | /* Do we fit in with the current stack dump size? */ | |
5588 | if ((u16) (header_size + stack_size) < header_size) { | |
5589 | /* | |
5590 | * If we overflow the maximum size for the sample, | |
5591 | * we customize the stack dump size to fit in. | |
5592 | */ | |
5593 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5594 | stack_size = round_up(stack_size, sizeof(u64)); | |
5595 | } | |
5596 | ||
5597 | return stack_size; | |
5598 | } | |
5599 | ||
5600 | static void | |
5601 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5602 | struct pt_regs *regs) | |
5603 | { | |
5604 | /* Case of a kernel thread, nothing to dump */ | |
5605 | if (!regs) { | |
5606 | u64 size = 0; | |
5607 | perf_output_put(handle, size); | |
5608 | } else { | |
5609 | unsigned long sp; | |
5610 | unsigned int rem; | |
5611 | u64 dyn_size; | |
5612 | ||
5613 | /* | |
5614 | * We dump: | |
5615 | * static size | |
5616 | * - the size requested by user or the best one we can fit | |
5617 | * in to the sample max size | |
5618 | * data | |
5619 | * - user stack dump data | |
5620 | * dynamic size | |
5621 | * - the actual dumped size | |
5622 | */ | |
5623 | ||
5624 | /* Static size. */ | |
5625 | perf_output_put(handle, dump_size); | |
5626 | ||
5627 | /* Data. */ | |
5628 | sp = perf_user_stack_pointer(regs); | |
5629 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5630 | dyn_size = dump_size - rem; | |
5631 | ||
5632 | perf_output_skip(handle, rem); | |
5633 | ||
5634 | /* Dynamic size. */ | |
5635 | perf_output_put(handle, dyn_size); | |
5636 | } | |
5637 | } | |
5638 | ||
c980d109 ACM |
5639 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5640 | struct perf_sample_data *data, | |
5641 | struct perf_event *event) | |
6844c09d ACM |
5642 | { |
5643 | u64 sample_type = event->attr.sample_type; | |
5644 | ||
5645 | data->type = sample_type; | |
5646 | header->size += event->id_header_size; | |
5647 | ||
5648 | if (sample_type & PERF_SAMPLE_TID) { | |
5649 | /* namespace issues */ | |
5650 | data->tid_entry.pid = perf_event_pid(event, current); | |
5651 | data->tid_entry.tid = perf_event_tid(event, current); | |
5652 | } | |
5653 | ||
5654 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5655 | data->time = perf_event_clock(event); |
6844c09d | 5656 | |
ff3d527c | 5657 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5658 | data->id = primary_event_id(event); |
5659 | ||
5660 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5661 | data->stream_id = event->id; | |
5662 | ||
5663 | if (sample_type & PERF_SAMPLE_CPU) { | |
5664 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5665 | data->cpu_entry.reserved = 0; | |
5666 | } | |
5667 | } | |
5668 | ||
76369139 FW |
5669 | void perf_event_header__init_id(struct perf_event_header *header, |
5670 | struct perf_sample_data *data, | |
5671 | struct perf_event *event) | |
c980d109 ACM |
5672 | { |
5673 | if (event->attr.sample_id_all) | |
5674 | __perf_event_header__init_id(header, data, event); | |
5675 | } | |
5676 | ||
5677 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5678 | struct perf_sample_data *data) | |
5679 | { | |
5680 | u64 sample_type = data->type; | |
5681 | ||
5682 | if (sample_type & PERF_SAMPLE_TID) | |
5683 | perf_output_put(handle, data->tid_entry); | |
5684 | ||
5685 | if (sample_type & PERF_SAMPLE_TIME) | |
5686 | perf_output_put(handle, data->time); | |
5687 | ||
5688 | if (sample_type & PERF_SAMPLE_ID) | |
5689 | perf_output_put(handle, data->id); | |
5690 | ||
5691 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5692 | perf_output_put(handle, data->stream_id); | |
5693 | ||
5694 | if (sample_type & PERF_SAMPLE_CPU) | |
5695 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5696 | |
5697 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5698 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5699 | } |
5700 | ||
76369139 FW |
5701 | void perf_event__output_id_sample(struct perf_event *event, |
5702 | struct perf_output_handle *handle, | |
5703 | struct perf_sample_data *sample) | |
c980d109 ACM |
5704 | { |
5705 | if (event->attr.sample_id_all) | |
5706 | __perf_event__output_id_sample(handle, sample); | |
5707 | } | |
5708 | ||
3dab77fb | 5709 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5710 | struct perf_event *event, |
5711 | u64 enabled, u64 running) | |
3dab77fb | 5712 | { |
cdd6c482 | 5713 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5714 | u64 values[4]; |
5715 | int n = 0; | |
5716 | ||
b5e58793 | 5717 | values[n++] = perf_event_count(event); |
3dab77fb | 5718 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5719 | values[n++] = enabled + |
cdd6c482 | 5720 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5721 | } |
5722 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5723 | values[n++] = running + |
cdd6c482 | 5724 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5725 | } |
5726 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5727 | values[n++] = primary_event_id(event); |
3dab77fb | 5728 | |
76369139 | 5729 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5730 | } |
5731 | ||
5732 | /* | |
cdd6c482 | 5733 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5734 | */ |
5735 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5736 | struct perf_event *event, |
5737 | u64 enabled, u64 running) | |
3dab77fb | 5738 | { |
cdd6c482 IM |
5739 | struct perf_event *leader = event->group_leader, *sub; |
5740 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5741 | u64 values[5]; |
5742 | int n = 0; | |
5743 | ||
5744 | values[n++] = 1 + leader->nr_siblings; | |
5745 | ||
5746 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5747 | values[n++] = enabled; |
3dab77fb PZ |
5748 | |
5749 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5750 | values[n++] = running; |
3dab77fb | 5751 | |
cdd6c482 | 5752 | if (leader != event) |
3dab77fb PZ |
5753 | leader->pmu->read(leader); |
5754 | ||
b5e58793 | 5755 | values[n++] = perf_event_count(leader); |
3dab77fb | 5756 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5757 | values[n++] = primary_event_id(leader); |
3dab77fb | 5758 | |
76369139 | 5759 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5760 | |
65abc865 | 5761 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5762 | n = 0; |
5763 | ||
6f5ab001 JO |
5764 | if ((sub != event) && |
5765 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5766 | sub->pmu->read(sub); |
5767 | ||
b5e58793 | 5768 | values[n++] = perf_event_count(sub); |
3dab77fb | 5769 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5770 | values[n++] = primary_event_id(sub); |
3dab77fb | 5771 | |
76369139 | 5772 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5773 | } |
5774 | } | |
5775 | ||
eed01528 SE |
5776 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5777 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5778 | ||
3dab77fb | 5779 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5780 | struct perf_event *event) |
3dab77fb | 5781 | { |
e3f3541c | 5782 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5783 | u64 read_format = event->attr.read_format; |
5784 | ||
5785 | /* | |
5786 | * compute total_time_enabled, total_time_running | |
5787 | * based on snapshot values taken when the event | |
5788 | * was last scheduled in. | |
5789 | * | |
5790 | * we cannot simply called update_context_time() | |
5791 | * because of locking issue as we are called in | |
5792 | * NMI context | |
5793 | */ | |
c4794295 | 5794 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5795 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5796 | |
cdd6c482 | 5797 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5798 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5799 | else |
eed01528 | 5800 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5801 | } |
5802 | ||
5622f295 MM |
5803 | void perf_output_sample(struct perf_output_handle *handle, |
5804 | struct perf_event_header *header, | |
5805 | struct perf_sample_data *data, | |
cdd6c482 | 5806 | struct perf_event *event) |
5622f295 MM |
5807 | { |
5808 | u64 sample_type = data->type; | |
5809 | ||
5810 | perf_output_put(handle, *header); | |
5811 | ||
ff3d527c AH |
5812 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5813 | perf_output_put(handle, data->id); | |
5814 | ||
5622f295 MM |
5815 | if (sample_type & PERF_SAMPLE_IP) |
5816 | perf_output_put(handle, data->ip); | |
5817 | ||
5818 | if (sample_type & PERF_SAMPLE_TID) | |
5819 | perf_output_put(handle, data->tid_entry); | |
5820 | ||
5821 | if (sample_type & PERF_SAMPLE_TIME) | |
5822 | perf_output_put(handle, data->time); | |
5823 | ||
5824 | if (sample_type & PERF_SAMPLE_ADDR) | |
5825 | perf_output_put(handle, data->addr); | |
5826 | ||
5827 | if (sample_type & PERF_SAMPLE_ID) | |
5828 | perf_output_put(handle, data->id); | |
5829 | ||
5830 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5831 | perf_output_put(handle, data->stream_id); | |
5832 | ||
5833 | if (sample_type & PERF_SAMPLE_CPU) | |
5834 | perf_output_put(handle, data->cpu_entry); | |
5835 | ||
5836 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5837 | perf_output_put(handle, data->period); | |
5838 | ||
5839 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5840 | perf_output_read(handle, event); |
5622f295 MM |
5841 | |
5842 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5843 | if (data->callchain) { | |
5844 | int size = 1; | |
5845 | ||
5846 | if (data->callchain) | |
5847 | size += data->callchain->nr; | |
5848 | ||
5849 | size *= sizeof(u64); | |
5850 | ||
76369139 | 5851 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5852 | } else { |
5853 | u64 nr = 0; | |
5854 | perf_output_put(handle, nr); | |
5855 | } | |
5856 | } | |
5857 | ||
5858 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5859 | struct perf_raw_record *raw = data->raw; |
5860 | ||
5861 | if (raw) { | |
5862 | struct perf_raw_frag *frag = &raw->frag; | |
5863 | ||
5864 | perf_output_put(handle, raw->size); | |
5865 | do { | |
5866 | if (frag->copy) { | |
5867 | __output_custom(handle, frag->copy, | |
5868 | frag->data, frag->size); | |
5869 | } else { | |
5870 | __output_copy(handle, frag->data, | |
5871 | frag->size); | |
5872 | } | |
5873 | if (perf_raw_frag_last(frag)) | |
5874 | break; | |
5875 | frag = frag->next; | |
5876 | } while (1); | |
5877 | if (frag->pad) | |
5878 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5879 | } else { |
5880 | struct { | |
5881 | u32 size; | |
5882 | u32 data; | |
5883 | } raw = { | |
5884 | .size = sizeof(u32), | |
5885 | .data = 0, | |
5886 | }; | |
5887 | perf_output_put(handle, raw); | |
5888 | } | |
5889 | } | |
a7ac67ea | 5890 | |
bce38cd5 SE |
5891 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5892 | if (data->br_stack) { | |
5893 | size_t size; | |
5894 | ||
5895 | size = data->br_stack->nr | |
5896 | * sizeof(struct perf_branch_entry); | |
5897 | ||
5898 | perf_output_put(handle, data->br_stack->nr); | |
5899 | perf_output_copy(handle, data->br_stack->entries, size); | |
5900 | } else { | |
5901 | /* | |
5902 | * we always store at least the value of nr | |
5903 | */ | |
5904 | u64 nr = 0; | |
5905 | perf_output_put(handle, nr); | |
5906 | } | |
5907 | } | |
4018994f JO |
5908 | |
5909 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5910 | u64 abi = data->regs_user.abi; | |
5911 | ||
5912 | /* | |
5913 | * If there are no regs to dump, notice it through | |
5914 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5915 | */ | |
5916 | perf_output_put(handle, abi); | |
5917 | ||
5918 | if (abi) { | |
5919 | u64 mask = event->attr.sample_regs_user; | |
5920 | perf_output_sample_regs(handle, | |
5921 | data->regs_user.regs, | |
5922 | mask); | |
5923 | } | |
5924 | } | |
c5ebcedb | 5925 | |
a5cdd40c | 5926 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5927 | perf_output_sample_ustack(handle, |
5928 | data->stack_user_size, | |
5929 | data->regs_user.regs); | |
a5cdd40c | 5930 | } |
c3feedf2 AK |
5931 | |
5932 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5933 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5934 | |
5935 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5936 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5937 | |
fdfbbd07 AK |
5938 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5939 | perf_output_put(handle, data->txn); | |
5940 | ||
60e2364e SE |
5941 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5942 | u64 abi = data->regs_intr.abi; | |
5943 | /* | |
5944 | * If there are no regs to dump, notice it through | |
5945 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5946 | */ | |
5947 | perf_output_put(handle, abi); | |
5948 | ||
5949 | if (abi) { | |
5950 | u64 mask = event->attr.sample_regs_intr; | |
5951 | ||
5952 | perf_output_sample_regs(handle, | |
5953 | data->regs_intr.regs, | |
5954 | mask); | |
5955 | } | |
5956 | } | |
5957 | ||
a5cdd40c PZ |
5958 | if (!event->attr.watermark) { |
5959 | int wakeup_events = event->attr.wakeup_events; | |
5960 | ||
5961 | if (wakeup_events) { | |
5962 | struct ring_buffer *rb = handle->rb; | |
5963 | int events = local_inc_return(&rb->events); | |
5964 | ||
5965 | if (events >= wakeup_events) { | |
5966 | local_sub(wakeup_events, &rb->events); | |
5967 | local_inc(&rb->wakeup); | |
5968 | } | |
5969 | } | |
5970 | } | |
5622f295 MM |
5971 | } |
5972 | ||
5973 | void perf_prepare_sample(struct perf_event_header *header, | |
5974 | struct perf_sample_data *data, | |
cdd6c482 | 5975 | struct perf_event *event, |
5622f295 | 5976 | struct pt_regs *regs) |
7b732a75 | 5977 | { |
cdd6c482 | 5978 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5979 | |
cdd6c482 | 5980 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5981 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5982 | |
5983 | header->misc = 0; | |
5984 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5985 | |
c980d109 | 5986 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5987 | |
c320c7b7 | 5988 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5989 | data->ip = perf_instruction_pointer(regs); |
5990 | ||
b23f3325 | 5991 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5992 | int size = 1; |
394ee076 | 5993 | |
e6dab5ff | 5994 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5995 | |
5996 | if (data->callchain) | |
5997 | size += data->callchain->nr; | |
5998 | ||
5999 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6000 | } |
6001 | ||
3a43ce68 | 6002 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6003 | struct perf_raw_record *raw = data->raw; |
6004 | int size; | |
6005 | ||
6006 | if (raw) { | |
6007 | struct perf_raw_frag *frag = &raw->frag; | |
6008 | u32 sum = 0; | |
6009 | ||
6010 | do { | |
6011 | sum += frag->size; | |
6012 | if (perf_raw_frag_last(frag)) | |
6013 | break; | |
6014 | frag = frag->next; | |
6015 | } while (1); | |
6016 | ||
6017 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6018 | raw->size = size - sizeof(u32); | |
6019 | frag->pad = raw->size - sum; | |
6020 | } else { | |
6021 | size = sizeof(u64); | |
6022 | } | |
a044560c | 6023 | |
7e3f977e | 6024 | header->size += size; |
7f453c24 | 6025 | } |
bce38cd5 SE |
6026 | |
6027 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6028 | int size = sizeof(u64); /* nr */ | |
6029 | if (data->br_stack) { | |
6030 | size += data->br_stack->nr | |
6031 | * sizeof(struct perf_branch_entry); | |
6032 | } | |
6033 | header->size += size; | |
6034 | } | |
4018994f | 6035 | |
2565711f | 6036 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6037 | perf_sample_regs_user(&data->regs_user, regs, |
6038 | &data->regs_user_copy); | |
2565711f | 6039 | |
4018994f JO |
6040 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6041 | /* regs dump ABI info */ | |
6042 | int size = sizeof(u64); | |
6043 | ||
4018994f JO |
6044 | if (data->regs_user.regs) { |
6045 | u64 mask = event->attr.sample_regs_user; | |
6046 | size += hweight64(mask) * sizeof(u64); | |
6047 | } | |
6048 | ||
6049 | header->size += size; | |
6050 | } | |
c5ebcedb JO |
6051 | |
6052 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6053 | /* | |
6054 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6055 | * processed as the last one or have additional check added | |
6056 | * in case new sample type is added, because we could eat | |
6057 | * up the rest of the sample size. | |
6058 | */ | |
c5ebcedb JO |
6059 | u16 stack_size = event->attr.sample_stack_user; |
6060 | u16 size = sizeof(u64); | |
6061 | ||
c5ebcedb | 6062 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6063 | data->regs_user.regs); |
c5ebcedb JO |
6064 | |
6065 | /* | |
6066 | * If there is something to dump, add space for the dump | |
6067 | * itself and for the field that tells the dynamic size, | |
6068 | * which is how many have been actually dumped. | |
6069 | */ | |
6070 | if (stack_size) | |
6071 | size += sizeof(u64) + stack_size; | |
6072 | ||
6073 | data->stack_user_size = stack_size; | |
6074 | header->size += size; | |
6075 | } | |
60e2364e SE |
6076 | |
6077 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6078 | /* regs dump ABI info */ | |
6079 | int size = sizeof(u64); | |
6080 | ||
6081 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6082 | ||
6083 | if (data->regs_intr.regs) { | |
6084 | u64 mask = event->attr.sample_regs_intr; | |
6085 | ||
6086 | size += hweight64(mask) * sizeof(u64); | |
6087 | } | |
6088 | ||
6089 | header->size += size; | |
6090 | } | |
5622f295 | 6091 | } |
7f453c24 | 6092 | |
9ecda41a WN |
6093 | static void __always_inline |
6094 | __perf_event_output(struct perf_event *event, | |
6095 | struct perf_sample_data *data, | |
6096 | struct pt_regs *regs, | |
6097 | int (*output_begin)(struct perf_output_handle *, | |
6098 | struct perf_event *, | |
6099 | unsigned int)) | |
5622f295 MM |
6100 | { |
6101 | struct perf_output_handle handle; | |
6102 | struct perf_event_header header; | |
689802b2 | 6103 | |
927c7a9e FW |
6104 | /* protect the callchain buffers */ |
6105 | rcu_read_lock(); | |
6106 | ||
cdd6c482 | 6107 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6108 | |
9ecda41a | 6109 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6110 | goto exit; |
0322cd6e | 6111 | |
cdd6c482 | 6112 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6113 | |
8a057d84 | 6114 | perf_output_end(&handle); |
927c7a9e FW |
6115 | |
6116 | exit: | |
6117 | rcu_read_unlock(); | |
0322cd6e PZ |
6118 | } |
6119 | ||
9ecda41a WN |
6120 | void |
6121 | perf_event_output_forward(struct perf_event *event, | |
6122 | struct perf_sample_data *data, | |
6123 | struct pt_regs *regs) | |
6124 | { | |
6125 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6126 | } | |
6127 | ||
6128 | void | |
6129 | perf_event_output_backward(struct perf_event *event, | |
6130 | struct perf_sample_data *data, | |
6131 | struct pt_regs *regs) | |
6132 | { | |
6133 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6134 | } | |
6135 | ||
6136 | void | |
6137 | perf_event_output(struct perf_event *event, | |
6138 | struct perf_sample_data *data, | |
6139 | struct pt_regs *regs) | |
6140 | { | |
6141 | __perf_event_output(event, data, regs, perf_output_begin); | |
6142 | } | |
6143 | ||
38b200d6 | 6144 | /* |
cdd6c482 | 6145 | * read event_id |
38b200d6 PZ |
6146 | */ |
6147 | ||
6148 | struct perf_read_event { | |
6149 | struct perf_event_header header; | |
6150 | ||
6151 | u32 pid; | |
6152 | u32 tid; | |
38b200d6 PZ |
6153 | }; |
6154 | ||
6155 | static void | |
cdd6c482 | 6156 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6157 | struct task_struct *task) |
6158 | { | |
6159 | struct perf_output_handle handle; | |
c980d109 | 6160 | struct perf_sample_data sample; |
dfc65094 | 6161 | struct perf_read_event read_event = { |
38b200d6 | 6162 | .header = { |
cdd6c482 | 6163 | .type = PERF_RECORD_READ, |
38b200d6 | 6164 | .misc = 0, |
c320c7b7 | 6165 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6166 | }, |
cdd6c482 IM |
6167 | .pid = perf_event_pid(event, task), |
6168 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6169 | }; |
3dab77fb | 6170 | int ret; |
38b200d6 | 6171 | |
c980d109 | 6172 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6173 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6174 | if (ret) |
6175 | return; | |
6176 | ||
dfc65094 | 6177 | perf_output_put(&handle, read_event); |
cdd6c482 | 6178 | perf_output_read(&handle, event); |
c980d109 | 6179 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6180 | |
38b200d6 PZ |
6181 | perf_output_end(&handle); |
6182 | } | |
6183 | ||
aab5b71e | 6184 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6185 | |
6186 | static void | |
aab5b71e PZ |
6187 | perf_iterate_ctx(struct perf_event_context *ctx, |
6188 | perf_iterate_f output, | |
b73e4fef | 6189 | void *data, bool all) |
52d857a8 JO |
6190 | { |
6191 | struct perf_event *event; | |
6192 | ||
6193 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6194 | if (!all) { |
6195 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6196 | continue; | |
6197 | if (!event_filter_match(event)) | |
6198 | continue; | |
6199 | } | |
6200 | ||
67516844 | 6201 | output(event, data); |
52d857a8 JO |
6202 | } |
6203 | } | |
6204 | ||
aab5b71e | 6205 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6206 | { |
6207 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6208 | struct perf_event *event; | |
6209 | ||
6210 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6211 | /* |
6212 | * Skip events that are not fully formed yet; ensure that | |
6213 | * if we observe event->ctx, both event and ctx will be | |
6214 | * complete enough. See perf_install_in_context(). | |
6215 | */ | |
6216 | if (!smp_load_acquire(&event->ctx)) | |
6217 | continue; | |
6218 | ||
f2fb6bef KL |
6219 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6220 | continue; | |
6221 | if (!event_filter_match(event)) | |
6222 | continue; | |
6223 | output(event, data); | |
6224 | } | |
6225 | } | |
6226 | ||
aab5b71e PZ |
6227 | /* |
6228 | * Iterate all events that need to receive side-band events. | |
6229 | * | |
6230 | * For new callers; ensure that account_pmu_sb_event() includes | |
6231 | * your event, otherwise it might not get delivered. | |
6232 | */ | |
52d857a8 | 6233 | static void |
aab5b71e | 6234 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6235 | struct perf_event_context *task_ctx) |
6236 | { | |
52d857a8 | 6237 | struct perf_event_context *ctx; |
52d857a8 JO |
6238 | int ctxn; |
6239 | ||
aab5b71e PZ |
6240 | rcu_read_lock(); |
6241 | preempt_disable(); | |
6242 | ||
4e93ad60 | 6243 | /* |
aab5b71e PZ |
6244 | * If we have task_ctx != NULL we only notify the task context itself. |
6245 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6246 | * context. |
6247 | */ | |
6248 | if (task_ctx) { | |
aab5b71e PZ |
6249 | perf_iterate_ctx(task_ctx, output, data, false); |
6250 | goto done; | |
4e93ad60 JO |
6251 | } |
6252 | ||
aab5b71e | 6253 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6254 | |
6255 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6256 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6257 | if (ctx) | |
aab5b71e | 6258 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6259 | } |
aab5b71e | 6260 | done: |
f2fb6bef | 6261 | preempt_enable(); |
52d857a8 | 6262 | rcu_read_unlock(); |
95ff4ca2 AS |
6263 | } |
6264 | ||
375637bc AS |
6265 | /* |
6266 | * Clear all file-based filters at exec, they'll have to be | |
6267 | * re-instated when/if these objects are mmapped again. | |
6268 | */ | |
6269 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6270 | { | |
6271 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6272 | struct perf_addr_filter *filter; | |
6273 | unsigned int restart = 0, count = 0; | |
6274 | unsigned long flags; | |
6275 | ||
6276 | if (!has_addr_filter(event)) | |
6277 | return; | |
6278 | ||
6279 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6280 | list_for_each_entry(filter, &ifh->list, entry) { | |
6281 | if (filter->inode) { | |
6282 | event->addr_filters_offs[count] = 0; | |
6283 | restart++; | |
6284 | } | |
6285 | ||
6286 | count++; | |
6287 | } | |
6288 | ||
6289 | if (restart) | |
6290 | event->addr_filters_gen++; | |
6291 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6292 | ||
6293 | if (restart) | |
767ae086 | 6294 | perf_event_stop(event, 1); |
375637bc AS |
6295 | } |
6296 | ||
6297 | void perf_event_exec(void) | |
6298 | { | |
6299 | struct perf_event_context *ctx; | |
6300 | int ctxn; | |
6301 | ||
6302 | rcu_read_lock(); | |
6303 | for_each_task_context_nr(ctxn) { | |
6304 | ctx = current->perf_event_ctxp[ctxn]; | |
6305 | if (!ctx) | |
6306 | continue; | |
6307 | ||
6308 | perf_event_enable_on_exec(ctxn); | |
6309 | ||
aab5b71e | 6310 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6311 | true); |
6312 | } | |
6313 | rcu_read_unlock(); | |
6314 | } | |
6315 | ||
95ff4ca2 AS |
6316 | struct remote_output { |
6317 | struct ring_buffer *rb; | |
6318 | int err; | |
6319 | }; | |
6320 | ||
6321 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6322 | { | |
6323 | struct perf_event *parent = event->parent; | |
6324 | struct remote_output *ro = data; | |
6325 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6326 | struct stop_event_data sd = { |
6327 | .event = event, | |
6328 | }; | |
95ff4ca2 AS |
6329 | |
6330 | if (!has_aux(event)) | |
6331 | return; | |
6332 | ||
6333 | if (!parent) | |
6334 | parent = event; | |
6335 | ||
6336 | /* | |
6337 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6338 | * ring-buffer, but it will be the child that's actually using it. |
6339 | * | |
6340 | * We are using event::rb to determine if the event should be stopped, | |
6341 | * however this may race with ring_buffer_attach() (through set_output), | |
6342 | * which will make us skip the event that actually needs to be stopped. | |
6343 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6344 | * its rb pointer. | |
95ff4ca2 AS |
6345 | */ |
6346 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6347 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6348 | } |
6349 | ||
6350 | static int __perf_pmu_output_stop(void *info) | |
6351 | { | |
6352 | struct perf_event *event = info; | |
6353 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6354 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6355 | struct remote_output ro = { |
6356 | .rb = event->rb, | |
6357 | }; | |
6358 | ||
6359 | rcu_read_lock(); | |
aab5b71e | 6360 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6361 | if (cpuctx->task_ctx) |
aab5b71e | 6362 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6363 | &ro, false); |
95ff4ca2 AS |
6364 | rcu_read_unlock(); |
6365 | ||
6366 | return ro.err; | |
6367 | } | |
6368 | ||
6369 | static void perf_pmu_output_stop(struct perf_event *event) | |
6370 | { | |
6371 | struct perf_event *iter; | |
6372 | int err, cpu; | |
6373 | ||
6374 | restart: | |
6375 | rcu_read_lock(); | |
6376 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6377 | /* | |
6378 | * For per-CPU events, we need to make sure that neither they | |
6379 | * nor their children are running; for cpu==-1 events it's | |
6380 | * sufficient to stop the event itself if it's active, since | |
6381 | * it can't have children. | |
6382 | */ | |
6383 | cpu = iter->cpu; | |
6384 | if (cpu == -1) | |
6385 | cpu = READ_ONCE(iter->oncpu); | |
6386 | ||
6387 | if (cpu == -1) | |
6388 | continue; | |
6389 | ||
6390 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6391 | if (err == -EAGAIN) { | |
6392 | rcu_read_unlock(); | |
6393 | goto restart; | |
6394 | } | |
6395 | } | |
6396 | rcu_read_unlock(); | |
52d857a8 JO |
6397 | } |
6398 | ||
60313ebe | 6399 | /* |
9f498cc5 PZ |
6400 | * task tracking -- fork/exit |
6401 | * | |
13d7a241 | 6402 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6403 | */ |
6404 | ||
9f498cc5 | 6405 | struct perf_task_event { |
3a80b4a3 | 6406 | struct task_struct *task; |
cdd6c482 | 6407 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6408 | |
6409 | struct { | |
6410 | struct perf_event_header header; | |
6411 | ||
6412 | u32 pid; | |
6413 | u32 ppid; | |
9f498cc5 PZ |
6414 | u32 tid; |
6415 | u32 ptid; | |
393b2ad8 | 6416 | u64 time; |
cdd6c482 | 6417 | } event_id; |
60313ebe PZ |
6418 | }; |
6419 | ||
67516844 JO |
6420 | static int perf_event_task_match(struct perf_event *event) |
6421 | { | |
13d7a241 SE |
6422 | return event->attr.comm || event->attr.mmap || |
6423 | event->attr.mmap2 || event->attr.mmap_data || | |
6424 | event->attr.task; | |
67516844 JO |
6425 | } |
6426 | ||
cdd6c482 | 6427 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6428 | void *data) |
60313ebe | 6429 | { |
52d857a8 | 6430 | struct perf_task_event *task_event = data; |
60313ebe | 6431 | struct perf_output_handle handle; |
c980d109 | 6432 | struct perf_sample_data sample; |
9f498cc5 | 6433 | struct task_struct *task = task_event->task; |
c980d109 | 6434 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6435 | |
67516844 JO |
6436 | if (!perf_event_task_match(event)) |
6437 | return; | |
6438 | ||
c980d109 | 6439 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6440 | |
c980d109 | 6441 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6442 | task_event->event_id.header.size); |
ef60777c | 6443 | if (ret) |
c980d109 | 6444 | goto out; |
60313ebe | 6445 | |
cdd6c482 IM |
6446 | task_event->event_id.pid = perf_event_pid(event, task); |
6447 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6448 | |
cdd6c482 IM |
6449 | task_event->event_id.tid = perf_event_tid(event, task); |
6450 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6451 | |
34f43927 PZ |
6452 | task_event->event_id.time = perf_event_clock(event); |
6453 | ||
cdd6c482 | 6454 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6455 | |
c980d109 ACM |
6456 | perf_event__output_id_sample(event, &handle, &sample); |
6457 | ||
60313ebe | 6458 | perf_output_end(&handle); |
c980d109 ACM |
6459 | out: |
6460 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6461 | } |
6462 | ||
cdd6c482 IM |
6463 | static void perf_event_task(struct task_struct *task, |
6464 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6465 | int new) |
60313ebe | 6466 | { |
9f498cc5 | 6467 | struct perf_task_event task_event; |
60313ebe | 6468 | |
cdd6c482 IM |
6469 | if (!atomic_read(&nr_comm_events) && |
6470 | !atomic_read(&nr_mmap_events) && | |
6471 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6472 | return; |
6473 | ||
9f498cc5 | 6474 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6475 | .task = task, |
6476 | .task_ctx = task_ctx, | |
cdd6c482 | 6477 | .event_id = { |
60313ebe | 6478 | .header = { |
cdd6c482 | 6479 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6480 | .misc = 0, |
cdd6c482 | 6481 | .size = sizeof(task_event.event_id), |
60313ebe | 6482 | }, |
573402db PZ |
6483 | /* .pid */ |
6484 | /* .ppid */ | |
9f498cc5 PZ |
6485 | /* .tid */ |
6486 | /* .ptid */ | |
34f43927 | 6487 | /* .time */ |
60313ebe PZ |
6488 | }, |
6489 | }; | |
6490 | ||
aab5b71e | 6491 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6492 | &task_event, |
6493 | task_ctx); | |
9f498cc5 PZ |
6494 | } |
6495 | ||
cdd6c482 | 6496 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6497 | { |
cdd6c482 | 6498 | perf_event_task(task, NULL, 1); |
e4222673 | 6499 | perf_event_namespaces(task); |
60313ebe PZ |
6500 | } |
6501 | ||
8d1b2d93 PZ |
6502 | /* |
6503 | * comm tracking | |
6504 | */ | |
6505 | ||
6506 | struct perf_comm_event { | |
22a4f650 IM |
6507 | struct task_struct *task; |
6508 | char *comm; | |
8d1b2d93 PZ |
6509 | int comm_size; |
6510 | ||
6511 | struct { | |
6512 | struct perf_event_header header; | |
6513 | ||
6514 | u32 pid; | |
6515 | u32 tid; | |
cdd6c482 | 6516 | } event_id; |
8d1b2d93 PZ |
6517 | }; |
6518 | ||
67516844 JO |
6519 | static int perf_event_comm_match(struct perf_event *event) |
6520 | { | |
6521 | return event->attr.comm; | |
6522 | } | |
6523 | ||
cdd6c482 | 6524 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6525 | void *data) |
8d1b2d93 | 6526 | { |
52d857a8 | 6527 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6528 | struct perf_output_handle handle; |
c980d109 | 6529 | struct perf_sample_data sample; |
cdd6c482 | 6530 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6531 | int ret; |
6532 | ||
67516844 JO |
6533 | if (!perf_event_comm_match(event)) |
6534 | return; | |
6535 | ||
c980d109 ACM |
6536 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6537 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6538 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6539 | |
6540 | if (ret) | |
c980d109 | 6541 | goto out; |
8d1b2d93 | 6542 | |
cdd6c482 IM |
6543 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6544 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6545 | |
cdd6c482 | 6546 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6547 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6548 | comm_event->comm_size); |
c980d109 ACM |
6549 | |
6550 | perf_event__output_id_sample(event, &handle, &sample); | |
6551 | ||
8d1b2d93 | 6552 | perf_output_end(&handle); |
c980d109 ACM |
6553 | out: |
6554 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6555 | } |
6556 | ||
cdd6c482 | 6557 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6558 | { |
413ee3b4 | 6559 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6560 | unsigned int size; |
8d1b2d93 | 6561 | |
413ee3b4 | 6562 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6563 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6564 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6565 | |
6566 | comm_event->comm = comm; | |
6567 | comm_event->comm_size = size; | |
6568 | ||
cdd6c482 | 6569 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6570 | |
aab5b71e | 6571 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6572 | comm_event, |
6573 | NULL); | |
8d1b2d93 PZ |
6574 | } |
6575 | ||
82b89778 | 6576 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6577 | { |
9ee318a7 PZ |
6578 | struct perf_comm_event comm_event; |
6579 | ||
cdd6c482 | 6580 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6581 | return; |
a63eaf34 | 6582 | |
9ee318a7 | 6583 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6584 | .task = task, |
573402db PZ |
6585 | /* .comm */ |
6586 | /* .comm_size */ | |
cdd6c482 | 6587 | .event_id = { |
573402db | 6588 | .header = { |
cdd6c482 | 6589 | .type = PERF_RECORD_COMM, |
82b89778 | 6590 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6591 | /* .size */ |
6592 | }, | |
6593 | /* .pid */ | |
6594 | /* .tid */ | |
8d1b2d93 PZ |
6595 | }, |
6596 | }; | |
6597 | ||
cdd6c482 | 6598 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6599 | } |
6600 | ||
e4222673 HB |
6601 | /* |
6602 | * namespaces tracking | |
6603 | */ | |
6604 | ||
6605 | struct perf_namespaces_event { | |
6606 | struct task_struct *task; | |
6607 | ||
6608 | struct { | |
6609 | struct perf_event_header header; | |
6610 | ||
6611 | u32 pid; | |
6612 | u32 tid; | |
6613 | u64 nr_namespaces; | |
6614 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
6615 | } event_id; | |
6616 | }; | |
6617 | ||
6618 | static int perf_event_namespaces_match(struct perf_event *event) | |
6619 | { | |
6620 | return event->attr.namespaces; | |
6621 | } | |
6622 | ||
6623 | static void perf_event_namespaces_output(struct perf_event *event, | |
6624 | void *data) | |
6625 | { | |
6626 | struct perf_namespaces_event *namespaces_event = data; | |
6627 | struct perf_output_handle handle; | |
6628 | struct perf_sample_data sample; | |
6629 | int ret; | |
6630 | ||
6631 | if (!perf_event_namespaces_match(event)) | |
6632 | return; | |
6633 | ||
6634 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
6635 | &sample, event); | |
6636 | ret = perf_output_begin(&handle, event, | |
6637 | namespaces_event->event_id.header.size); | |
6638 | if (ret) | |
6639 | return; | |
6640 | ||
6641 | namespaces_event->event_id.pid = perf_event_pid(event, | |
6642 | namespaces_event->task); | |
6643 | namespaces_event->event_id.tid = perf_event_tid(event, | |
6644 | namespaces_event->task); | |
6645 | ||
6646 | perf_output_put(&handle, namespaces_event->event_id); | |
6647 | ||
6648 | perf_event__output_id_sample(event, &handle, &sample); | |
6649 | ||
6650 | perf_output_end(&handle); | |
6651 | } | |
6652 | ||
6653 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
6654 | struct task_struct *task, | |
6655 | const struct proc_ns_operations *ns_ops) | |
6656 | { | |
6657 | struct path ns_path; | |
6658 | struct inode *ns_inode; | |
6659 | void *error; | |
6660 | ||
6661 | error = ns_get_path(&ns_path, task, ns_ops); | |
6662 | if (!error) { | |
6663 | ns_inode = ns_path.dentry->d_inode; | |
6664 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
6665 | ns_link_info->ino = ns_inode->i_ino; | |
6666 | } | |
6667 | } | |
6668 | ||
6669 | void perf_event_namespaces(struct task_struct *task) | |
6670 | { | |
6671 | struct perf_namespaces_event namespaces_event; | |
6672 | struct perf_ns_link_info *ns_link_info; | |
6673 | ||
6674 | if (!atomic_read(&nr_namespaces_events)) | |
6675 | return; | |
6676 | ||
6677 | namespaces_event = (struct perf_namespaces_event){ | |
6678 | .task = task, | |
6679 | .event_id = { | |
6680 | .header = { | |
6681 | .type = PERF_RECORD_NAMESPACES, | |
6682 | .misc = 0, | |
6683 | .size = sizeof(namespaces_event.event_id), | |
6684 | }, | |
6685 | /* .pid */ | |
6686 | /* .tid */ | |
6687 | .nr_namespaces = NR_NAMESPACES, | |
6688 | /* .link_info[NR_NAMESPACES] */ | |
6689 | }, | |
6690 | }; | |
6691 | ||
6692 | ns_link_info = namespaces_event.event_id.link_info; | |
6693 | ||
6694 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
6695 | task, &mntns_operations); | |
6696 | ||
6697 | #ifdef CONFIG_USER_NS | |
6698 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
6699 | task, &userns_operations); | |
6700 | #endif | |
6701 | #ifdef CONFIG_NET_NS | |
6702 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
6703 | task, &netns_operations); | |
6704 | #endif | |
6705 | #ifdef CONFIG_UTS_NS | |
6706 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
6707 | task, &utsns_operations); | |
6708 | #endif | |
6709 | #ifdef CONFIG_IPC_NS | |
6710 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
6711 | task, &ipcns_operations); | |
6712 | #endif | |
6713 | #ifdef CONFIG_PID_NS | |
6714 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
6715 | task, &pidns_operations); | |
6716 | #endif | |
6717 | #ifdef CONFIG_CGROUPS | |
6718 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
6719 | task, &cgroupns_operations); | |
6720 | #endif | |
6721 | ||
6722 | perf_iterate_sb(perf_event_namespaces_output, | |
6723 | &namespaces_event, | |
6724 | NULL); | |
6725 | } | |
6726 | ||
0a4a9391 PZ |
6727 | /* |
6728 | * mmap tracking | |
6729 | */ | |
6730 | ||
6731 | struct perf_mmap_event { | |
089dd79d PZ |
6732 | struct vm_area_struct *vma; |
6733 | ||
6734 | const char *file_name; | |
6735 | int file_size; | |
13d7a241 SE |
6736 | int maj, min; |
6737 | u64 ino; | |
6738 | u64 ino_generation; | |
f972eb63 | 6739 | u32 prot, flags; |
0a4a9391 PZ |
6740 | |
6741 | struct { | |
6742 | struct perf_event_header header; | |
6743 | ||
6744 | u32 pid; | |
6745 | u32 tid; | |
6746 | u64 start; | |
6747 | u64 len; | |
6748 | u64 pgoff; | |
cdd6c482 | 6749 | } event_id; |
0a4a9391 PZ |
6750 | }; |
6751 | ||
67516844 JO |
6752 | static int perf_event_mmap_match(struct perf_event *event, |
6753 | void *data) | |
6754 | { | |
6755 | struct perf_mmap_event *mmap_event = data; | |
6756 | struct vm_area_struct *vma = mmap_event->vma; | |
6757 | int executable = vma->vm_flags & VM_EXEC; | |
6758 | ||
6759 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6760 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6761 | } |
6762 | ||
cdd6c482 | 6763 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6764 | void *data) |
0a4a9391 | 6765 | { |
52d857a8 | 6766 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6767 | struct perf_output_handle handle; |
c980d109 | 6768 | struct perf_sample_data sample; |
cdd6c482 | 6769 | int size = mmap_event->event_id.header.size; |
c980d109 | 6770 | int ret; |
0a4a9391 | 6771 | |
67516844 JO |
6772 | if (!perf_event_mmap_match(event, data)) |
6773 | return; | |
6774 | ||
13d7a241 SE |
6775 | if (event->attr.mmap2) { |
6776 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6777 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6778 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6779 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6780 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6781 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6782 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6783 | } |
6784 | ||
c980d109 ACM |
6785 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6786 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6787 | mmap_event->event_id.header.size); |
0a4a9391 | 6788 | if (ret) |
c980d109 | 6789 | goto out; |
0a4a9391 | 6790 | |
cdd6c482 IM |
6791 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6792 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6793 | |
cdd6c482 | 6794 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6795 | |
6796 | if (event->attr.mmap2) { | |
6797 | perf_output_put(&handle, mmap_event->maj); | |
6798 | perf_output_put(&handle, mmap_event->min); | |
6799 | perf_output_put(&handle, mmap_event->ino); | |
6800 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6801 | perf_output_put(&handle, mmap_event->prot); |
6802 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6803 | } |
6804 | ||
76369139 | 6805 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6806 | mmap_event->file_size); |
c980d109 ACM |
6807 | |
6808 | perf_event__output_id_sample(event, &handle, &sample); | |
6809 | ||
78d613eb | 6810 | perf_output_end(&handle); |
c980d109 ACM |
6811 | out: |
6812 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6813 | } |
6814 | ||
cdd6c482 | 6815 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6816 | { |
089dd79d PZ |
6817 | struct vm_area_struct *vma = mmap_event->vma; |
6818 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6819 | int maj = 0, min = 0; |
6820 | u64 ino = 0, gen = 0; | |
f972eb63 | 6821 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6822 | unsigned int size; |
6823 | char tmp[16]; | |
6824 | char *buf = NULL; | |
2c42cfbf | 6825 | char *name; |
413ee3b4 | 6826 | |
0b3589be PZ |
6827 | if (vma->vm_flags & VM_READ) |
6828 | prot |= PROT_READ; | |
6829 | if (vma->vm_flags & VM_WRITE) | |
6830 | prot |= PROT_WRITE; | |
6831 | if (vma->vm_flags & VM_EXEC) | |
6832 | prot |= PROT_EXEC; | |
6833 | ||
6834 | if (vma->vm_flags & VM_MAYSHARE) | |
6835 | flags = MAP_SHARED; | |
6836 | else | |
6837 | flags = MAP_PRIVATE; | |
6838 | ||
6839 | if (vma->vm_flags & VM_DENYWRITE) | |
6840 | flags |= MAP_DENYWRITE; | |
6841 | if (vma->vm_flags & VM_MAYEXEC) | |
6842 | flags |= MAP_EXECUTABLE; | |
6843 | if (vma->vm_flags & VM_LOCKED) | |
6844 | flags |= MAP_LOCKED; | |
6845 | if (vma->vm_flags & VM_HUGETLB) | |
6846 | flags |= MAP_HUGETLB; | |
6847 | ||
0a4a9391 | 6848 | if (file) { |
13d7a241 SE |
6849 | struct inode *inode; |
6850 | dev_t dev; | |
3ea2f2b9 | 6851 | |
2c42cfbf | 6852 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6853 | if (!buf) { |
c7e548b4 ON |
6854 | name = "//enomem"; |
6855 | goto cpy_name; | |
0a4a9391 | 6856 | } |
413ee3b4 | 6857 | /* |
3ea2f2b9 | 6858 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6859 | * need to add enough zero bytes after the string to handle |
6860 | * the 64bit alignment we do later. | |
6861 | */ | |
9bf39ab2 | 6862 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6863 | if (IS_ERR(name)) { |
c7e548b4 ON |
6864 | name = "//toolong"; |
6865 | goto cpy_name; | |
0a4a9391 | 6866 | } |
13d7a241 SE |
6867 | inode = file_inode(vma->vm_file); |
6868 | dev = inode->i_sb->s_dev; | |
6869 | ino = inode->i_ino; | |
6870 | gen = inode->i_generation; | |
6871 | maj = MAJOR(dev); | |
6872 | min = MINOR(dev); | |
f972eb63 | 6873 | |
c7e548b4 | 6874 | goto got_name; |
0a4a9391 | 6875 | } else { |
fbe26abe JO |
6876 | if (vma->vm_ops && vma->vm_ops->name) { |
6877 | name = (char *) vma->vm_ops->name(vma); | |
6878 | if (name) | |
6879 | goto cpy_name; | |
6880 | } | |
6881 | ||
2c42cfbf | 6882 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6883 | if (name) |
6884 | goto cpy_name; | |
089dd79d | 6885 | |
32c5fb7e | 6886 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6887 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6888 | name = "[heap]"; |
6889 | goto cpy_name; | |
32c5fb7e ON |
6890 | } |
6891 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6892 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6893 | name = "[stack]"; |
6894 | goto cpy_name; | |
089dd79d PZ |
6895 | } |
6896 | ||
c7e548b4 ON |
6897 | name = "//anon"; |
6898 | goto cpy_name; | |
0a4a9391 PZ |
6899 | } |
6900 | ||
c7e548b4 ON |
6901 | cpy_name: |
6902 | strlcpy(tmp, name, sizeof(tmp)); | |
6903 | name = tmp; | |
0a4a9391 | 6904 | got_name: |
2c42cfbf PZ |
6905 | /* |
6906 | * Since our buffer works in 8 byte units we need to align our string | |
6907 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6908 | * zero'd out to avoid leaking random bits to userspace. | |
6909 | */ | |
6910 | size = strlen(name)+1; | |
6911 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6912 | name[size++] = '\0'; | |
0a4a9391 PZ |
6913 | |
6914 | mmap_event->file_name = name; | |
6915 | mmap_event->file_size = size; | |
13d7a241 SE |
6916 | mmap_event->maj = maj; |
6917 | mmap_event->min = min; | |
6918 | mmap_event->ino = ino; | |
6919 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6920 | mmap_event->prot = prot; |
6921 | mmap_event->flags = flags; | |
0a4a9391 | 6922 | |
2fe85427 SE |
6923 | if (!(vma->vm_flags & VM_EXEC)) |
6924 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6925 | ||
cdd6c482 | 6926 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6927 | |
aab5b71e | 6928 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6929 | mmap_event, |
6930 | NULL); | |
665c2142 | 6931 | |
0a4a9391 PZ |
6932 | kfree(buf); |
6933 | } | |
6934 | ||
375637bc AS |
6935 | /* |
6936 | * Check whether inode and address range match filter criteria. | |
6937 | */ | |
6938 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6939 | struct file *file, unsigned long offset, | |
6940 | unsigned long size) | |
6941 | { | |
45063097 | 6942 | if (filter->inode != file_inode(file)) |
375637bc AS |
6943 | return false; |
6944 | ||
6945 | if (filter->offset > offset + size) | |
6946 | return false; | |
6947 | ||
6948 | if (filter->offset + filter->size < offset) | |
6949 | return false; | |
6950 | ||
6951 | return true; | |
6952 | } | |
6953 | ||
6954 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6955 | { | |
6956 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6957 | struct vm_area_struct *vma = data; | |
6958 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6959 | struct file *file = vma->vm_file; | |
6960 | struct perf_addr_filter *filter; | |
6961 | unsigned int restart = 0, count = 0; | |
6962 | ||
6963 | if (!has_addr_filter(event)) | |
6964 | return; | |
6965 | ||
6966 | if (!file) | |
6967 | return; | |
6968 | ||
6969 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6970 | list_for_each_entry(filter, &ifh->list, entry) { | |
6971 | if (perf_addr_filter_match(filter, file, off, | |
6972 | vma->vm_end - vma->vm_start)) { | |
6973 | event->addr_filters_offs[count] = vma->vm_start; | |
6974 | restart++; | |
6975 | } | |
6976 | ||
6977 | count++; | |
6978 | } | |
6979 | ||
6980 | if (restart) | |
6981 | event->addr_filters_gen++; | |
6982 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6983 | ||
6984 | if (restart) | |
767ae086 | 6985 | perf_event_stop(event, 1); |
375637bc AS |
6986 | } |
6987 | ||
6988 | /* | |
6989 | * Adjust all task's events' filters to the new vma | |
6990 | */ | |
6991 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6992 | { | |
6993 | struct perf_event_context *ctx; | |
6994 | int ctxn; | |
6995 | ||
12b40a23 MP |
6996 | /* |
6997 | * Data tracing isn't supported yet and as such there is no need | |
6998 | * to keep track of anything that isn't related to executable code: | |
6999 | */ | |
7000 | if (!(vma->vm_flags & VM_EXEC)) | |
7001 | return; | |
7002 | ||
375637bc AS |
7003 | rcu_read_lock(); |
7004 | for_each_task_context_nr(ctxn) { | |
7005 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7006 | if (!ctx) | |
7007 | continue; | |
7008 | ||
aab5b71e | 7009 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7010 | } |
7011 | rcu_read_unlock(); | |
7012 | } | |
7013 | ||
3af9e859 | 7014 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7015 | { |
9ee318a7 PZ |
7016 | struct perf_mmap_event mmap_event; |
7017 | ||
cdd6c482 | 7018 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7019 | return; |
7020 | ||
7021 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7022 | .vma = vma, |
573402db PZ |
7023 | /* .file_name */ |
7024 | /* .file_size */ | |
cdd6c482 | 7025 | .event_id = { |
573402db | 7026 | .header = { |
cdd6c482 | 7027 | .type = PERF_RECORD_MMAP, |
39447b38 | 7028 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7029 | /* .size */ |
7030 | }, | |
7031 | /* .pid */ | |
7032 | /* .tid */ | |
089dd79d PZ |
7033 | .start = vma->vm_start, |
7034 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7035 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7036 | }, |
13d7a241 SE |
7037 | /* .maj (attr_mmap2 only) */ |
7038 | /* .min (attr_mmap2 only) */ | |
7039 | /* .ino (attr_mmap2 only) */ | |
7040 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7041 | /* .prot (attr_mmap2 only) */ |
7042 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7043 | }; |
7044 | ||
375637bc | 7045 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7046 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7047 | } |
7048 | ||
68db7e98 AS |
7049 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7050 | unsigned long size, u64 flags) | |
7051 | { | |
7052 | struct perf_output_handle handle; | |
7053 | struct perf_sample_data sample; | |
7054 | struct perf_aux_event { | |
7055 | struct perf_event_header header; | |
7056 | u64 offset; | |
7057 | u64 size; | |
7058 | u64 flags; | |
7059 | } rec = { | |
7060 | .header = { | |
7061 | .type = PERF_RECORD_AUX, | |
7062 | .misc = 0, | |
7063 | .size = sizeof(rec), | |
7064 | }, | |
7065 | .offset = head, | |
7066 | .size = size, | |
7067 | .flags = flags, | |
7068 | }; | |
7069 | int ret; | |
7070 | ||
7071 | perf_event_header__init_id(&rec.header, &sample, event); | |
7072 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7073 | ||
7074 | if (ret) | |
7075 | return; | |
7076 | ||
7077 | perf_output_put(&handle, rec); | |
7078 | perf_event__output_id_sample(event, &handle, &sample); | |
7079 | ||
7080 | perf_output_end(&handle); | |
7081 | } | |
7082 | ||
f38b0dbb KL |
7083 | /* |
7084 | * Lost/dropped samples logging | |
7085 | */ | |
7086 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7087 | { | |
7088 | struct perf_output_handle handle; | |
7089 | struct perf_sample_data sample; | |
7090 | int ret; | |
7091 | ||
7092 | struct { | |
7093 | struct perf_event_header header; | |
7094 | u64 lost; | |
7095 | } lost_samples_event = { | |
7096 | .header = { | |
7097 | .type = PERF_RECORD_LOST_SAMPLES, | |
7098 | .misc = 0, | |
7099 | .size = sizeof(lost_samples_event), | |
7100 | }, | |
7101 | .lost = lost, | |
7102 | }; | |
7103 | ||
7104 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7105 | ||
7106 | ret = perf_output_begin(&handle, event, | |
7107 | lost_samples_event.header.size); | |
7108 | if (ret) | |
7109 | return; | |
7110 | ||
7111 | perf_output_put(&handle, lost_samples_event); | |
7112 | perf_event__output_id_sample(event, &handle, &sample); | |
7113 | perf_output_end(&handle); | |
7114 | } | |
7115 | ||
45ac1403 AH |
7116 | /* |
7117 | * context_switch tracking | |
7118 | */ | |
7119 | ||
7120 | struct perf_switch_event { | |
7121 | struct task_struct *task; | |
7122 | struct task_struct *next_prev; | |
7123 | ||
7124 | struct { | |
7125 | struct perf_event_header header; | |
7126 | u32 next_prev_pid; | |
7127 | u32 next_prev_tid; | |
7128 | } event_id; | |
7129 | }; | |
7130 | ||
7131 | static int perf_event_switch_match(struct perf_event *event) | |
7132 | { | |
7133 | return event->attr.context_switch; | |
7134 | } | |
7135 | ||
7136 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7137 | { | |
7138 | struct perf_switch_event *se = data; | |
7139 | struct perf_output_handle handle; | |
7140 | struct perf_sample_data sample; | |
7141 | int ret; | |
7142 | ||
7143 | if (!perf_event_switch_match(event)) | |
7144 | return; | |
7145 | ||
7146 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7147 | if (event->ctx->task) { | |
7148 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7149 | se->event_id.header.size = sizeof(se->event_id.header); | |
7150 | } else { | |
7151 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7152 | se->event_id.header.size = sizeof(se->event_id); | |
7153 | se->event_id.next_prev_pid = | |
7154 | perf_event_pid(event, se->next_prev); | |
7155 | se->event_id.next_prev_tid = | |
7156 | perf_event_tid(event, se->next_prev); | |
7157 | } | |
7158 | ||
7159 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7160 | ||
7161 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7162 | if (ret) | |
7163 | return; | |
7164 | ||
7165 | if (event->ctx->task) | |
7166 | perf_output_put(&handle, se->event_id.header); | |
7167 | else | |
7168 | perf_output_put(&handle, se->event_id); | |
7169 | ||
7170 | perf_event__output_id_sample(event, &handle, &sample); | |
7171 | ||
7172 | perf_output_end(&handle); | |
7173 | } | |
7174 | ||
7175 | static void perf_event_switch(struct task_struct *task, | |
7176 | struct task_struct *next_prev, bool sched_in) | |
7177 | { | |
7178 | struct perf_switch_event switch_event; | |
7179 | ||
7180 | /* N.B. caller checks nr_switch_events != 0 */ | |
7181 | ||
7182 | switch_event = (struct perf_switch_event){ | |
7183 | .task = task, | |
7184 | .next_prev = next_prev, | |
7185 | .event_id = { | |
7186 | .header = { | |
7187 | /* .type */ | |
7188 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7189 | /* .size */ | |
7190 | }, | |
7191 | /* .next_prev_pid */ | |
7192 | /* .next_prev_tid */ | |
7193 | }, | |
7194 | }; | |
7195 | ||
aab5b71e | 7196 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7197 | &switch_event, |
7198 | NULL); | |
7199 | } | |
7200 | ||
a78ac325 PZ |
7201 | /* |
7202 | * IRQ throttle logging | |
7203 | */ | |
7204 | ||
cdd6c482 | 7205 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7206 | { |
7207 | struct perf_output_handle handle; | |
c980d109 | 7208 | struct perf_sample_data sample; |
a78ac325 PZ |
7209 | int ret; |
7210 | ||
7211 | struct { | |
7212 | struct perf_event_header header; | |
7213 | u64 time; | |
cca3f454 | 7214 | u64 id; |
7f453c24 | 7215 | u64 stream_id; |
a78ac325 PZ |
7216 | } throttle_event = { |
7217 | .header = { | |
cdd6c482 | 7218 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7219 | .misc = 0, |
7220 | .size = sizeof(throttle_event), | |
7221 | }, | |
34f43927 | 7222 | .time = perf_event_clock(event), |
cdd6c482 IM |
7223 | .id = primary_event_id(event), |
7224 | .stream_id = event->id, | |
a78ac325 PZ |
7225 | }; |
7226 | ||
966ee4d6 | 7227 | if (enable) |
cdd6c482 | 7228 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7229 | |
c980d109 ACM |
7230 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7231 | ||
7232 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7233 | throttle_event.header.size); |
a78ac325 PZ |
7234 | if (ret) |
7235 | return; | |
7236 | ||
7237 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7238 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7239 | perf_output_end(&handle); |
7240 | } | |
7241 | ||
ec0d7729 AS |
7242 | static void perf_log_itrace_start(struct perf_event *event) |
7243 | { | |
7244 | struct perf_output_handle handle; | |
7245 | struct perf_sample_data sample; | |
7246 | struct perf_aux_event { | |
7247 | struct perf_event_header header; | |
7248 | u32 pid; | |
7249 | u32 tid; | |
7250 | } rec; | |
7251 | int ret; | |
7252 | ||
7253 | if (event->parent) | |
7254 | event = event->parent; | |
7255 | ||
7256 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
7257 | event->hw.itrace_started) | |
7258 | return; | |
7259 | ||
ec0d7729 AS |
7260 | rec.header.type = PERF_RECORD_ITRACE_START; |
7261 | rec.header.misc = 0; | |
7262 | rec.header.size = sizeof(rec); | |
7263 | rec.pid = perf_event_pid(event, current); | |
7264 | rec.tid = perf_event_tid(event, current); | |
7265 | ||
7266 | perf_event_header__init_id(&rec.header, &sample, event); | |
7267 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7268 | ||
7269 | if (ret) | |
7270 | return; | |
7271 | ||
7272 | perf_output_put(&handle, rec); | |
7273 | perf_event__output_id_sample(event, &handle, &sample); | |
7274 | ||
7275 | perf_output_end(&handle); | |
7276 | } | |
7277 | ||
475113d9 JO |
7278 | static int |
7279 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7280 | { |
cdd6c482 | 7281 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7282 | int ret = 0; |
475113d9 | 7283 | u64 seq; |
96398826 | 7284 | |
e050e3f0 SE |
7285 | seq = __this_cpu_read(perf_throttled_seq); |
7286 | if (seq != hwc->interrupts_seq) { | |
7287 | hwc->interrupts_seq = seq; | |
7288 | hwc->interrupts = 1; | |
7289 | } else { | |
7290 | hwc->interrupts++; | |
7291 | if (unlikely(throttle | |
7292 | && hwc->interrupts >= max_samples_per_tick)) { | |
7293 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7294 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7295 | hwc->interrupts = MAX_INTERRUPTS; |
7296 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7297 | ret = 1; |
7298 | } | |
e050e3f0 | 7299 | } |
60db5e09 | 7300 | |
cdd6c482 | 7301 | if (event->attr.freq) { |
def0a9b2 | 7302 | u64 now = perf_clock(); |
abd50713 | 7303 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7304 | |
abd50713 | 7305 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7306 | |
abd50713 | 7307 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7308 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7309 | } |
7310 | ||
475113d9 JO |
7311 | return ret; |
7312 | } | |
7313 | ||
7314 | int perf_event_account_interrupt(struct perf_event *event) | |
7315 | { | |
7316 | return __perf_event_account_interrupt(event, 1); | |
7317 | } | |
7318 | ||
7319 | /* | |
7320 | * Generic event overflow handling, sampling. | |
7321 | */ | |
7322 | ||
7323 | static int __perf_event_overflow(struct perf_event *event, | |
7324 | int throttle, struct perf_sample_data *data, | |
7325 | struct pt_regs *regs) | |
7326 | { | |
7327 | int events = atomic_read(&event->event_limit); | |
7328 | int ret = 0; | |
7329 | ||
7330 | /* | |
7331 | * Non-sampling counters might still use the PMI to fold short | |
7332 | * hardware counters, ignore those. | |
7333 | */ | |
7334 | if (unlikely(!is_sampling_event(event))) | |
7335 | return 0; | |
7336 | ||
7337 | ret = __perf_event_account_interrupt(event, throttle); | |
7338 | ||
2023b359 PZ |
7339 | /* |
7340 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7341 | * events |
2023b359 PZ |
7342 | */ |
7343 | ||
cdd6c482 IM |
7344 | event->pending_kill = POLL_IN; |
7345 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7346 | ret = 1; |
cdd6c482 | 7347 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7348 | |
7349 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7350 | } |
7351 | ||
aa6a5f3c | 7352 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7353 | |
fed66e2c | 7354 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7355 | event->pending_wakeup = 1; |
7356 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7357 | } |
7358 | ||
79f14641 | 7359 | return ret; |
f6c7d5fe PZ |
7360 | } |
7361 | ||
a8b0ca17 | 7362 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7363 | struct perf_sample_data *data, |
7364 | struct pt_regs *regs) | |
850bc73f | 7365 | { |
a8b0ca17 | 7366 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7367 | } |
7368 | ||
15dbf27c | 7369 | /* |
cdd6c482 | 7370 | * Generic software event infrastructure |
15dbf27c PZ |
7371 | */ |
7372 | ||
b28ab83c PZ |
7373 | struct swevent_htable { |
7374 | struct swevent_hlist *swevent_hlist; | |
7375 | struct mutex hlist_mutex; | |
7376 | int hlist_refcount; | |
7377 | ||
7378 | /* Recursion avoidance in each contexts */ | |
7379 | int recursion[PERF_NR_CONTEXTS]; | |
7380 | }; | |
7381 | ||
7382 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7383 | ||
7b4b6658 | 7384 | /* |
cdd6c482 IM |
7385 | * We directly increment event->count and keep a second value in |
7386 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7387 | * is kept in the range [-sample_period, 0] so that we can use the |
7388 | * sign as trigger. | |
7389 | */ | |
7390 | ||
ab573844 | 7391 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7392 | { |
cdd6c482 | 7393 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7394 | u64 period = hwc->last_period; |
7395 | u64 nr, offset; | |
7396 | s64 old, val; | |
7397 | ||
7398 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7399 | |
7400 | again: | |
e7850595 | 7401 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7402 | if (val < 0) |
7403 | return 0; | |
15dbf27c | 7404 | |
7b4b6658 PZ |
7405 | nr = div64_u64(period + val, period); |
7406 | offset = nr * period; | |
7407 | val -= offset; | |
e7850595 | 7408 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7409 | goto again; |
15dbf27c | 7410 | |
7b4b6658 | 7411 | return nr; |
15dbf27c PZ |
7412 | } |
7413 | ||
0cff784a | 7414 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7415 | struct perf_sample_data *data, |
5622f295 | 7416 | struct pt_regs *regs) |
15dbf27c | 7417 | { |
cdd6c482 | 7418 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7419 | int throttle = 0; |
15dbf27c | 7420 | |
0cff784a PZ |
7421 | if (!overflow) |
7422 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7423 | |
7b4b6658 PZ |
7424 | if (hwc->interrupts == MAX_INTERRUPTS) |
7425 | return; | |
15dbf27c | 7426 | |
7b4b6658 | 7427 | for (; overflow; overflow--) { |
a8b0ca17 | 7428 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7429 | data, regs)) { |
7b4b6658 PZ |
7430 | /* |
7431 | * We inhibit the overflow from happening when | |
7432 | * hwc->interrupts == MAX_INTERRUPTS. | |
7433 | */ | |
7434 | break; | |
7435 | } | |
cf450a73 | 7436 | throttle = 1; |
7b4b6658 | 7437 | } |
15dbf27c PZ |
7438 | } |
7439 | ||
a4eaf7f1 | 7440 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7441 | struct perf_sample_data *data, |
5622f295 | 7442 | struct pt_regs *regs) |
7b4b6658 | 7443 | { |
cdd6c482 | 7444 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7445 | |
e7850595 | 7446 | local64_add(nr, &event->count); |
d6d020e9 | 7447 | |
0cff784a PZ |
7448 | if (!regs) |
7449 | return; | |
7450 | ||
6c7e550f | 7451 | if (!is_sampling_event(event)) |
7b4b6658 | 7452 | return; |
d6d020e9 | 7453 | |
5d81e5cf AV |
7454 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7455 | data->period = nr; | |
7456 | return perf_swevent_overflow(event, 1, data, regs); | |
7457 | } else | |
7458 | data->period = event->hw.last_period; | |
7459 | ||
0cff784a | 7460 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7461 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7462 | |
e7850595 | 7463 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7464 | return; |
df1a132b | 7465 | |
a8b0ca17 | 7466 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7467 | } |
7468 | ||
f5ffe02e FW |
7469 | static int perf_exclude_event(struct perf_event *event, |
7470 | struct pt_regs *regs) | |
7471 | { | |
a4eaf7f1 | 7472 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7473 | return 1; |
a4eaf7f1 | 7474 | |
f5ffe02e FW |
7475 | if (regs) { |
7476 | if (event->attr.exclude_user && user_mode(regs)) | |
7477 | return 1; | |
7478 | ||
7479 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7480 | return 1; | |
7481 | } | |
7482 | ||
7483 | return 0; | |
7484 | } | |
7485 | ||
cdd6c482 | 7486 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7487 | enum perf_type_id type, |
6fb2915d LZ |
7488 | u32 event_id, |
7489 | struct perf_sample_data *data, | |
7490 | struct pt_regs *regs) | |
15dbf27c | 7491 | { |
cdd6c482 | 7492 | if (event->attr.type != type) |
a21ca2ca | 7493 | return 0; |
f5ffe02e | 7494 | |
cdd6c482 | 7495 | if (event->attr.config != event_id) |
15dbf27c PZ |
7496 | return 0; |
7497 | ||
f5ffe02e FW |
7498 | if (perf_exclude_event(event, regs)) |
7499 | return 0; | |
15dbf27c PZ |
7500 | |
7501 | return 1; | |
7502 | } | |
7503 | ||
76e1d904 FW |
7504 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7505 | { | |
7506 | u64 val = event_id | (type << 32); | |
7507 | ||
7508 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7509 | } | |
7510 | ||
49f135ed FW |
7511 | static inline struct hlist_head * |
7512 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7513 | { |
49f135ed FW |
7514 | u64 hash = swevent_hash(type, event_id); |
7515 | ||
7516 | return &hlist->heads[hash]; | |
7517 | } | |
76e1d904 | 7518 | |
49f135ed FW |
7519 | /* For the read side: events when they trigger */ |
7520 | static inline struct hlist_head * | |
b28ab83c | 7521 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7522 | { |
7523 | struct swevent_hlist *hlist; | |
76e1d904 | 7524 | |
b28ab83c | 7525 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7526 | if (!hlist) |
7527 | return NULL; | |
7528 | ||
49f135ed FW |
7529 | return __find_swevent_head(hlist, type, event_id); |
7530 | } | |
7531 | ||
7532 | /* For the event head insertion and removal in the hlist */ | |
7533 | static inline struct hlist_head * | |
b28ab83c | 7534 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7535 | { |
7536 | struct swevent_hlist *hlist; | |
7537 | u32 event_id = event->attr.config; | |
7538 | u64 type = event->attr.type; | |
7539 | ||
7540 | /* | |
7541 | * Event scheduling is always serialized against hlist allocation | |
7542 | * and release. Which makes the protected version suitable here. | |
7543 | * The context lock guarantees that. | |
7544 | */ | |
b28ab83c | 7545 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7546 | lockdep_is_held(&event->ctx->lock)); |
7547 | if (!hlist) | |
7548 | return NULL; | |
7549 | ||
7550 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7551 | } |
7552 | ||
7553 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7554 | u64 nr, |
76e1d904 FW |
7555 | struct perf_sample_data *data, |
7556 | struct pt_regs *regs) | |
15dbf27c | 7557 | { |
4a32fea9 | 7558 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7559 | struct perf_event *event; |
76e1d904 | 7560 | struct hlist_head *head; |
15dbf27c | 7561 | |
76e1d904 | 7562 | rcu_read_lock(); |
b28ab83c | 7563 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7564 | if (!head) |
7565 | goto end; | |
7566 | ||
b67bfe0d | 7567 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7568 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7569 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7570 | } |
76e1d904 FW |
7571 | end: |
7572 | rcu_read_unlock(); | |
15dbf27c PZ |
7573 | } |
7574 | ||
86038c5e PZI |
7575 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7576 | ||
4ed7c92d | 7577 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7578 | { |
4a32fea9 | 7579 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7580 | |
b28ab83c | 7581 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7582 | } |
645e8cc0 | 7583 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7584 | |
98b5c2c6 | 7585 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7586 | { |
4a32fea9 | 7587 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7588 | |
b28ab83c | 7589 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7590 | } |
15dbf27c | 7591 | |
86038c5e | 7592 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7593 | { |
a4234bfc | 7594 | struct perf_sample_data data; |
4ed7c92d | 7595 | |
86038c5e | 7596 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7597 | return; |
a4234bfc | 7598 | |
fd0d000b | 7599 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7600 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7601 | } |
7602 | ||
7603 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7604 | { | |
7605 | int rctx; | |
7606 | ||
7607 | preempt_disable_notrace(); | |
7608 | rctx = perf_swevent_get_recursion_context(); | |
7609 | if (unlikely(rctx < 0)) | |
7610 | goto fail; | |
7611 | ||
7612 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7613 | |
7614 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7615 | fail: |
1c024eca | 7616 | preempt_enable_notrace(); |
b8e83514 PZ |
7617 | } |
7618 | ||
cdd6c482 | 7619 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7620 | { |
15dbf27c PZ |
7621 | } |
7622 | ||
a4eaf7f1 | 7623 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7624 | { |
4a32fea9 | 7625 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7626 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7627 | struct hlist_head *head; |
7628 | ||
6c7e550f | 7629 | if (is_sampling_event(event)) { |
7b4b6658 | 7630 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7631 | perf_swevent_set_period(event); |
7b4b6658 | 7632 | } |
76e1d904 | 7633 | |
a4eaf7f1 PZ |
7634 | hwc->state = !(flags & PERF_EF_START); |
7635 | ||
b28ab83c | 7636 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7637 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7638 | return -EINVAL; |
7639 | ||
7640 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7641 | perf_event_update_userpage(event); |
76e1d904 | 7642 | |
15dbf27c PZ |
7643 | return 0; |
7644 | } | |
7645 | ||
a4eaf7f1 | 7646 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7647 | { |
76e1d904 | 7648 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7649 | } |
7650 | ||
a4eaf7f1 | 7651 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7652 | { |
a4eaf7f1 | 7653 | event->hw.state = 0; |
d6d020e9 | 7654 | } |
aa9c4c0f | 7655 | |
a4eaf7f1 | 7656 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7657 | { |
a4eaf7f1 | 7658 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7659 | } |
7660 | ||
49f135ed FW |
7661 | /* Deref the hlist from the update side */ |
7662 | static inline struct swevent_hlist * | |
b28ab83c | 7663 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7664 | { |
b28ab83c PZ |
7665 | return rcu_dereference_protected(swhash->swevent_hlist, |
7666 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7667 | } |
7668 | ||
b28ab83c | 7669 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7670 | { |
b28ab83c | 7671 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7672 | |
49f135ed | 7673 | if (!hlist) |
76e1d904 FW |
7674 | return; |
7675 | ||
70691d4a | 7676 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7677 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7678 | } |
7679 | ||
3b364d7b | 7680 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7681 | { |
b28ab83c | 7682 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7683 | |
b28ab83c | 7684 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7685 | |
b28ab83c PZ |
7686 | if (!--swhash->hlist_refcount) |
7687 | swevent_hlist_release(swhash); | |
76e1d904 | 7688 | |
b28ab83c | 7689 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7690 | } |
7691 | ||
3b364d7b | 7692 | static void swevent_hlist_put(void) |
76e1d904 FW |
7693 | { |
7694 | int cpu; | |
7695 | ||
76e1d904 | 7696 | for_each_possible_cpu(cpu) |
3b364d7b | 7697 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7698 | } |
7699 | ||
3b364d7b | 7700 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7701 | { |
b28ab83c | 7702 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7703 | int err = 0; |
7704 | ||
b28ab83c | 7705 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7706 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7707 | struct swevent_hlist *hlist; |
7708 | ||
7709 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7710 | if (!hlist) { | |
7711 | err = -ENOMEM; | |
7712 | goto exit; | |
7713 | } | |
b28ab83c | 7714 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7715 | } |
b28ab83c | 7716 | swhash->hlist_refcount++; |
9ed6060d | 7717 | exit: |
b28ab83c | 7718 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7719 | |
7720 | return err; | |
7721 | } | |
7722 | ||
3b364d7b | 7723 | static int swevent_hlist_get(void) |
76e1d904 | 7724 | { |
3b364d7b | 7725 | int err, cpu, failed_cpu; |
76e1d904 | 7726 | |
76e1d904 FW |
7727 | get_online_cpus(); |
7728 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7729 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7730 | if (err) { |
7731 | failed_cpu = cpu; | |
7732 | goto fail; | |
7733 | } | |
7734 | } | |
7735 | put_online_cpus(); | |
7736 | ||
7737 | return 0; | |
9ed6060d | 7738 | fail: |
76e1d904 FW |
7739 | for_each_possible_cpu(cpu) { |
7740 | if (cpu == failed_cpu) | |
7741 | break; | |
3b364d7b | 7742 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7743 | } |
7744 | ||
7745 | put_online_cpus(); | |
7746 | return err; | |
7747 | } | |
7748 | ||
c5905afb | 7749 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7750 | |
b0a873eb PZ |
7751 | static void sw_perf_event_destroy(struct perf_event *event) |
7752 | { | |
7753 | u64 event_id = event->attr.config; | |
95476b64 | 7754 | |
b0a873eb PZ |
7755 | WARN_ON(event->parent); |
7756 | ||
c5905afb | 7757 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7758 | swevent_hlist_put(); |
b0a873eb PZ |
7759 | } |
7760 | ||
7761 | static int perf_swevent_init(struct perf_event *event) | |
7762 | { | |
8176cced | 7763 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7764 | |
7765 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7766 | return -ENOENT; | |
7767 | ||
2481c5fa SE |
7768 | /* |
7769 | * no branch sampling for software events | |
7770 | */ | |
7771 | if (has_branch_stack(event)) | |
7772 | return -EOPNOTSUPP; | |
7773 | ||
b0a873eb PZ |
7774 | switch (event_id) { |
7775 | case PERF_COUNT_SW_CPU_CLOCK: | |
7776 | case PERF_COUNT_SW_TASK_CLOCK: | |
7777 | return -ENOENT; | |
7778 | ||
7779 | default: | |
7780 | break; | |
7781 | } | |
7782 | ||
ce677831 | 7783 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7784 | return -ENOENT; |
7785 | ||
7786 | if (!event->parent) { | |
7787 | int err; | |
7788 | ||
3b364d7b | 7789 | err = swevent_hlist_get(); |
b0a873eb PZ |
7790 | if (err) |
7791 | return err; | |
7792 | ||
c5905afb | 7793 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7794 | event->destroy = sw_perf_event_destroy; |
7795 | } | |
7796 | ||
7797 | return 0; | |
7798 | } | |
7799 | ||
7800 | static struct pmu perf_swevent = { | |
89a1e187 | 7801 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7802 | |
34f43927 PZ |
7803 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7804 | ||
b0a873eb | 7805 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7806 | .add = perf_swevent_add, |
7807 | .del = perf_swevent_del, | |
7808 | .start = perf_swevent_start, | |
7809 | .stop = perf_swevent_stop, | |
1c024eca | 7810 | .read = perf_swevent_read, |
1c024eca PZ |
7811 | }; |
7812 | ||
b0a873eb PZ |
7813 | #ifdef CONFIG_EVENT_TRACING |
7814 | ||
1c024eca PZ |
7815 | static int perf_tp_filter_match(struct perf_event *event, |
7816 | struct perf_sample_data *data) | |
7817 | { | |
7e3f977e | 7818 | void *record = data->raw->frag.data; |
1c024eca | 7819 | |
b71b437e PZ |
7820 | /* only top level events have filters set */ |
7821 | if (event->parent) | |
7822 | event = event->parent; | |
7823 | ||
1c024eca PZ |
7824 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7825 | return 1; | |
7826 | return 0; | |
7827 | } | |
7828 | ||
7829 | static int perf_tp_event_match(struct perf_event *event, | |
7830 | struct perf_sample_data *data, | |
7831 | struct pt_regs *regs) | |
7832 | { | |
a0f7d0f7 FW |
7833 | if (event->hw.state & PERF_HES_STOPPED) |
7834 | return 0; | |
580d607c PZ |
7835 | /* |
7836 | * All tracepoints are from kernel-space. | |
7837 | */ | |
7838 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7839 | return 0; |
7840 | ||
7841 | if (!perf_tp_filter_match(event, data)) | |
7842 | return 0; | |
7843 | ||
7844 | return 1; | |
7845 | } | |
7846 | ||
85b67bcb AS |
7847 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7848 | struct trace_event_call *call, u64 count, | |
7849 | struct pt_regs *regs, struct hlist_head *head, | |
7850 | struct task_struct *task) | |
7851 | { | |
7852 | struct bpf_prog *prog = call->prog; | |
7853 | ||
7854 | if (prog) { | |
7855 | *(struct pt_regs **)raw_data = regs; | |
7856 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7857 | perf_swevent_put_recursion_context(rctx); | |
7858 | return; | |
7859 | } | |
7860 | } | |
7861 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7862 | rctx, task); | |
7863 | } | |
7864 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7865 | ||
1e1dcd93 | 7866 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7867 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7868 | struct task_struct *task) | |
95476b64 FW |
7869 | { |
7870 | struct perf_sample_data data; | |
1c024eca | 7871 | struct perf_event *event; |
1c024eca | 7872 | |
95476b64 | 7873 | struct perf_raw_record raw = { |
7e3f977e DB |
7874 | .frag = { |
7875 | .size = entry_size, | |
7876 | .data = record, | |
7877 | }, | |
95476b64 FW |
7878 | }; |
7879 | ||
1e1dcd93 | 7880 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7881 | data.raw = &raw; |
7882 | ||
1e1dcd93 AS |
7883 | perf_trace_buf_update(record, event_type); |
7884 | ||
b67bfe0d | 7885 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7886 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7887 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7888 | } |
ecc55f84 | 7889 | |
e6dab5ff AV |
7890 | /* |
7891 | * If we got specified a target task, also iterate its context and | |
7892 | * deliver this event there too. | |
7893 | */ | |
7894 | if (task && task != current) { | |
7895 | struct perf_event_context *ctx; | |
7896 | struct trace_entry *entry = record; | |
7897 | ||
7898 | rcu_read_lock(); | |
7899 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7900 | if (!ctx) | |
7901 | goto unlock; | |
7902 | ||
7903 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7904 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7905 | continue; | |
7906 | if (event->attr.config != entry->type) | |
7907 | continue; | |
7908 | if (perf_tp_event_match(event, &data, regs)) | |
7909 | perf_swevent_event(event, count, &data, regs); | |
7910 | } | |
7911 | unlock: | |
7912 | rcu_read_unlock(); | |
7913 | } | |
7914 | ||
ecc55f84 | 7915 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7916 | } |
7917 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7918 | ||
cdd6c482 | 7919 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7920 | { |
1c024eca | 7921 | perf_trace_destroy(event); |
e077df4f PZ |
7922 | } |
7923 | ||
b0a873eb | 7924 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7925 | { |
76e1d904 FW |
7926 | int err; |
7927 | ||
b0a873eb PZ |
7928 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7929 | return -ENOENT; | |
7930 | ||
2481c5fa SE |
7931 | /* |
7932 | * no branch sampling for tracepoint events | |
7933 | */ | |
7934 | if (has_branch_stack(event)) | |
7935 | return -EOPNOTSUPP; | |
7936 | ||
1c024eca PZ |
7937 | err = perf_trace_init(event); |
7938 | if (err) | |
b0a873eb | 7939 | return err; |
e077df4f | 7940 | |
cdd6c482 | 7941 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7942 | |
b0a873eb PZ |
7943 | return 0; |
7944 | } | |
7945 | ||
7946 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7947 | .task_ctx_nr = perf_sw_context, |
7948 | ||
b0a873eb | 7949 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7950 | .add = perf_trace_add, |
7951 | .del = perf_trace_del, | |
7952 | .start = perf_swevent_start, | |
7953 | .stop = perf_swevent_stop, | |
b0a873eb | 7954 | .read = perf_swevent_read, |
b0a873eb PZ |
7955 | }; |
7956 | ||
7957 | static inline void perf_tp_register(void) | |
7958 | { | |
2e80a82a | 7959 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7960 | } |
6fb2915d | 7961 | |
6fb2915d LZ |
7962 | static void perf_event_free_filter(struct perf_event *event) |
7963 | { | |
7964 | ftrace_profile_free_filter(event); | |
7965 | } | |
7966 | ||
aa6a5f3c AS |
7967 | #ifdef CONFIG_BPF_SYSCALL |
7968 | static void bpf_overflow_handler(struct perf_event *event, | |
7969 | struct perf_sample_data *data, | |
7970 | struct pt_regs *regs) | |
7971 | { | |
7972 | struct bpf_perf_event_data_kern ctx = { | |
7973 | .data = data, | |
7974 | .regs = regs, | |
7975 | }; | |
7976 | int ret = 0; | |
7977 | ||
7978 | preempt_disable(); | |
7979 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
7980 | goto out; | |
7981 | rcu_read_lock(); | |
88575199 | 7982 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
7983 | rcu_read_unlock(); |
7984 | out: | |
7985 | __this_cpu_dec(bpf_prog_active); | |
7986 | preempt_enable(); | |
7987 | if (!ret) | |
7988 | return; | |
7989 | ||
7990 | event->orig_overflow_handler(event, data, regs); | |
7991 | } | |
7992 | ||
7993 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7994 | { | |
7995 | struct bpf_prog *prog; | |
7996 | ||
7997 | if (event->overflow_handler_context) | |
7998 | /* hw breakpoint or kernel counter */ | |
7999 | return -EINVAL; | |
8000 | ||
8001 | if (event->prog) | |
8002 | return -EEXIST; | |
8003 | ||
8004 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8005 | if (IS_ERR(prog)) | |
8006 | return PTR_ERR(prog); | |
8007 | ||
8008 | event->prog = prog; | |
8009 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8010 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8011 | return 0; | |
8012 | } | |
8013 | ||
8014 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8015 | { | |
8016 | struct bpf_prog *prog = event->prog; | |
8017 | ||
8018 | if (!prog) | |
8019 | return; | |
8020 | ||
8021 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
8022 | event->prog = NULL; | |
8023 | bpf_prog_put(prog); | |
8024 | } | |
8025 | #else | |
8026 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8027 | { | |
8028 | return -EOPNOTSUPP; | |
8029 | } | |
8030 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8031 | { | |
8032 | } | |
8033 | #endif | |
8034 | ||
2541517c AS |
8035 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8036 | { | |
98b5c2c6 | 8037 | bool is_kprobe, is_tracepoint; |
2541517c AS |
8038 | struct bpf_prog *prog; |
8039 | ||
aa6a5f3c AS |
8040 | if (event->attr.type == PERF_TYPE_HARDWARE || |
8041 | event->attr.type == PERF_TYPE_SOFTWARE) | |
8042 | return perf_event_set_bpf_handler(event, prog_fd); | |
8043 | ||
2541517c AS |
8044 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8045 | return -EINVAL; | |
8046 | ||
8047 | if (event->tp_event->prog) | |
8048 | return -EEXIST; | |
8049 | ||
98b5c2c6 AS |
8050 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
8051 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
8052 | if (!is_kprobe && !is_tracepoint) | |
8053 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
8054 | return -EINVAL; |
8055 | ||
8056 | prog = bpf_prog_get(prog_fd); | |
8057 | if (IS_ERR(prog)) | |
8058 | return PTR_ERR(prog); | |
8059 | ||
98b5c2c6 AS |
8060 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
8061 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
8062 | /* valid fd, but invalid bpf program type */ |
8063 | bpf_prog_put(prog); | |
8064 | return -EINVAL; | |
8065 | } | |
8066 | ||
32bbe007 AS |
8067 | if (is_tracepoint) { |
8068 | int off = trace_event_get_offsets(event->tp_event); | |
8069 | ||
8070 | if (prog->aux->max_ctx_offset > off) { | |
8071 | bpf_prog_put(prog); | |
8072 | return -EACCES; | |
8073 | } | |
8074 | } | |
2541517c AS |
8075 | event->tp_event->prog = prog; |
8076 | ||
8077 | return 0; | |
8078 | } | |
8079 | ||
8080 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8081 | { | |
8082 | struct bpf_prog *prog; | |
8083 | ||
aa6a5f3c AS |
8084 | perf_event_free_bpf_handler(event); |
8085 | ||
2541517c AS |
8086 | if (!event->tp_event) |
8087 | return; | |
8088 | ||
8089 | prog = event->tp_event->prog; | |
8090 | if (prog) { | |
8091 | event->tp_event->prog = NULL; | |
1aacde3d | 8092 | bpf_prog_put(prog); |
2541517c AS |
8093 | } |
8094 | } | |
8095 | ||
e077df4f | 8096 | #else |
6fb2915d | 8097 | |
b0a873eb | 8098 | static inline void perf_tp_register(void) |
e077df4f | 8099 | { |
e077df4f | 8100 | } |
6fb2915d | 8101 | |
6fb2915d LZ |
8102 | static void perf_event_free_filter(struct perf_event *event) |
8103 | { | |
8104 | } | |
8105 | ||
2541517c AS |
8106 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8107 | { | |
8108 | return -ENOENT; | |
8109 | } | |
8110 | ||
8111 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8112 | { | |
8113 | } | |
07b139c8 | 8114 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 8115 | |
24f1e32c | 8116 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 8117 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 8118 | { |
f5ffe02e FW |
8119 | struct perf_sample_data sample; |
8120 | struct pt_regs *regs = data; | |
8121 | ||
fd0d000b | 8122 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 8123 | |
a4eaf7f1 | 8124 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 8125 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
8126 | } |
8127 | #endif | |
8128 | ||
375637bc AS |
8129 | /* |
8130 | * Allocate a new address filter | |
8131 | */ | |
8132 | static struct perf_addr_filter * | |
8133 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
8134 | { | |
8135 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
8136 | struct perf_addr_filter *filter; | |
8137 | ||
8138 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
8139 | if (!filter) | |
8140 | return NULL; | |
8141 | ||
8142 | INIT_LIST_HEAD(&filter->entry); | |
8143 | list_add_tail(&filter->entry, filters); | |
8144 | ||
8145 | return filter; | |
8146 | } | |
8147 | ||
8148 | static void free_filters_list(struct list_head *filters) | |
8149 | { | |
8150 | struct perf_addr_filter *filter, *iter; | |
8151 | ||
8152 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
8153 | if (filter->inode) | |
8154 | iput(filter->inode); | |
8155 | list_del(&filter->entry); | |
8156 | kfree(filter); | |
8157 | } | |
8158 | } | |
8159 | ||
8160 | /* | |
8161 | * Free existing address filters and optionally install new ones | |
8162 | */ | |
8163 | static void perf_addr_filters_splice(struct perf_event *event, | |
8164 | struct list_head *head) | |
8165 | { | |
8166 | unsigned long flags; | |
8167 | LIST_HEAD(list); | |
8168 | ||
8169 | if (!has_addr_filter(event)) | |
8170 | return; | |
8171 | ||
8172 | /* don't bother with children, they don't have their own filters */ | |
8173 | if (event->parent) | |
8174 | return; | |
8175 | ||
8176 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
8177 | ||
8178 | list_splice_init(&event->addr_filters.list, &list); | |
8179 | if (head) | |
8180 | list_splice(head, &event->addr_filters.list); | |
8181 | ||
8182 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
8183 | ||
8184 | free_filters_list(&list); | |
8185 | } | |
8186 | ||
8187 | /* | |
8188 | * Scan through mm's vmas and see if one of them matches the | |
8189 | * @filter; if so, adjust filter's address range. | |
8190 | * Called with mm::mmap_sem down for reading. | |
8191 | */ | |
8192 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8193 | struct mm_struct *mm) | |
8194 | { | |
8195 | struct vm_area_struct *vma; | |
8196 | ||
8197 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8198 | struct file *file = vma->vm_file; | |
8199 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8200 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8201 | ||
8202 | if (!file) | |
8203 | continue; | |
8204 | ||
8205 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8206 | continue; | |
8207 | ||
8208 | return vma->vm_start; | |
8209 | } | |
8210 | ||
8211 | return 0; | |
8212 | } | |
8213 | ||
8214 | /* | |
8215 | * Update event's address range filters based on the | |
8216 | * task's existing mappings, if any. | |
8217 | */ | |
8218 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8219 | { | |
8220 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8221 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8222 | struct perf_addr_filter *filter; | |
8223 | struct mm_struct *mm = NULL; | |
8224 | unsigned int count = 0; | |
8225 | unsigned long flags; | |
8226 | ||
8227 | /* | |
8228 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8229 | * will stop on the parent's child_mutex that our caller is also holding | |
8230 | */ | |
8231 | if (task == TASK_TOMBSTONE) | |
8232 | return; | |
8233 | ||
6ce77bfd AS |
8234 | if (!ifh->nr_file_filters) |
8235 | return; | |
8236 | ||
375637bc AS |
8237 | mm = get_task_mm(event->ctx->task); |
8238 | if (!mm) | |
8239 | goto restart; | |
8240 | ||
8241 | down_read(&mm->mmap_sem); | |
8242 | ||
8243 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8244 | list_for_each_entry(filter, &ifh->list, entry) { | |
8245 | event->addr_filters_offs[count] = 0; | |
8246 | ||
99f5bc9b MP |
8247 | /* |
8248 | * Adjust base offset if the filter is associated to a binary | |
8249 | * that needs to be mapped: | |
8250 | */ | |
8251 | if (filter->inode) | |
375637bc AS |
8252 | event->addr_filters_offs[count] = |
8253 | perf_addr_filter_apply(filter, mm); | |
8254 | ||
8255 | count++; | |
8256 | } | |
8257 | ||
8258 | event->addr_filters_gen++; | |
8259 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8260 | ||
8261 | up_read(&mm->mmap_sem); | |
8262 | ||
8263 | mmput(mm); | |
8264 | ||
8265 | restart: | |
767ae086 | 8266 | perf_event_stop(event, 1); |
375637bc AS |
8267 | } |
8268 | ||
8269 | /* | |
8270 | * Address range filtering: limiting the data to certain | |
8271 | * instruction address ranges. Filters are ioctl()ed to us from | |
8272 | * userspace as ascii strings. | |
8273 | * | |
8274 | * Filter string format: | |
8275 | * | |
8276 | * ACTION RANGE_SPEC | |
8277 | * where ACTION is one of the | |
8278 | * * "filter": limit the trace to this region | |
8279 | * * "start": start tracing from this address | |
8280 | * * "stop": stop tracing at this address/region; | |
8281 | * RANGE_SPEC is | |
8282 | * * for kernel addresses: <start address>[/<size>] | |
8283 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8284 | * | |
8285 | * if <size> is not specified, the range is treated as a single address. | |
8286 | */ | |
8287 | enum { | |
e96271f3 | 8288 | IF_ACT_NONE = -1, |
375637bc AS |
8289 | IF_ACT_FILTER, |
8290 | IF_ACT_START, | |
8291 | IF_ACT_STOP, | |
8292 | IF_SRC_FILE, | |
8293 | IF_SRC_KERNEL, | |
8294 | IF_SRC_FILEADDR, | |
8295 | IF_SRC_KERNELADDR, | |
8296 | }; | |
8297 | ||
8298 | enum { | |
8299 | IF_STATE_ACTION = 0, | |
8300 | IF_STATE_SOURCE, | |
8301 | IF_STATE_END, | |
8302 | }; | |
8303 | ||
8304 | static const match_table_t if_tokens = { | |
8305 | { IF_ACT_FILTER, "filter" }, | |
8306 | { IF_ACT_START, "start" }, | |
8307 | { IF_ACT_STOP, "stop" }, | |
8308 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8309 | { IF_SRC_KERNEL, "%u/%u" }, | |
8310 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8311 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8312 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8313 | }; |
8314 | ||
8315 | /* | |
8316 | * Address filter string parser | |
8317 | */ | |
8318 | static int | |
8319 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8320 | struct list_head *filters) | |
8321 | { | |
8322 | struct perf_addr_filter *filter = NULL; | |
8323 | char *start, *orig, *filename = NULL; | |
8324 | struct path path; | |
8325 | substring_t args[MAX_OPT_ARGS]; | |
8326 | int state = IF_STATE_ACTION, token; | |
8327 | unsigned int kernel = 0; | |
8328 | int ret = -EINVAL; | |
8329 | ||
8330 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8331 | if (!fstr) | |
8332 | return -ENOMEM; | |
8333 | ||
8334 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8335 | ret = -EINVAL; | |
8336 | ||
8337 | if (!*start) | |
8338 | continue; | |
8339 | ||
8340 | /* filter definition begins */ | |
8341 | if (state == IF_STATE_ACTION) { | |
8342 | filter = perf_addr_filter_new(event, filters); | |
8343 | if (!filter) | |
8344 | goto fail; | |
8345 | } | |
8346 | ||
8347 | token = match_token(start, if_tokens, args); | |
8348 | switch (token) { | |
8349 | case IF_ACT_FILTER: | |
8350 | case IF_ACT_START: | |
8351 | filter->filter = 1; | |
8352 | ||
8353 | case IF_ACT_STOP: | |
8354 | if (state != IF_STATE_ACTION) | |
8355 | goto fail; | |
8356 | ||
8357 | state = IF_STATE_SOURCE; | |
8358 | break; | |
8359 | ||
8360 | case IF_SRC_KERNELADDR: | |
8361 | case IF_SRC_KERNEL: | |
8362 | kernel = 1; | |
8363 | ||
8364 | case IF_SRC_FILEADDR: | |
8365 | case IF_SRC_FILE: | |
8366 | if (state != IF_STATE_SOURCE) | |
8367 | goto fail; | |
8368 | ||
8369 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8370 | filter->range = 1; | |
8371 | ||
8372 | *args[0].to = 0; | |
8373 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8374 | if (ret) | |
8375 | goto fail; | |
8376 | ||
8377 | if (filter->range) { | |
8378 | *args[1].to = 0; | |
8379 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8380 | if (ret) | |
8381 | goto fail; | |
8382 | } | |
8383 | ||
4059ffd0 MP |
8384 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8385 | int fpos = filter->range ? 2 : 1; | |
8386 | ||
8387 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8388 | if (!filename) { |
8389 | ret = -ENOMEM; | |
8390 | goto fail; | |
8391 | } | |
8392 | } | |
8393 | ||
8394 | state = IF_STATE_END; | |
8395 | break; | |
8396 | ||
8397 | default: | |
8398 | goto fail; | |
8399 | } | |
8400 | ||
8401 | /* | |
8402 | * Filter definition is fully parsed, validate and install it. | |
8403 | * Make sure that it doesn't contradict itself or the event's | |
8404 | * attribute. | |
8405 | */ | |
8406 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 8407 | ret = -EINVAL; |
375637bc AS |
8408 | if (kernel && event->attr.exclude_kernel) |
8409 | goto fail; | |
8410 | ||
8411 | if (!kernel) { | |
8412 | if (!filename) | |
8413 | goto fail; | |
8414 | ||
6ce77bfd AS |
8415 | /* |
8416 | * For now, we only support file-based filters | |
8417 | * in per-task events; doing so for CPU-wide | |
8418 | * events requires additional context switching | |
8419 | * trickery, since same object code will be | |
8420 | * mapped at different virtual addresses in | |
8421 | * different processes. | |
8422 | */ | |
8423 | ret = -EOPNOTSUPP; | |
8424 | if (!event->ctx->task) | |
8425 | goto fail_free_name; | |
8426 | ||
375637bc AS |
8427 | /* look up the path and grab its inode */ |
8428 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8429 | if (ret) | |
8430 | goto fail_free_name; | |
8431 | ||
8432 | filter->inode = igrab(d_inode(path.dentry)); | |
8433 | path_put(&path); | |
8434 | kfree(filename); | |
8435 | filename = NULL; | |
8436 | ||
8437 | ret = -EINVAL; | |
8438 | if (!filter->inode || | |
8439 | !S_ISREG(filter->inode->i_mode)) | |
8440 | /* free_filters_list() will iput() */ | |
8441 | goto fail; | |
6ce77bfd AS |
8442 | |
8443 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
8444 | } |
8445 | ||
8446 | /* ready to consume more filters */ | |
8447 | state = IF_STATE_ACTION; | |
8448 | filter = NULL; | |
8449 | } | |
8450 | } | |
8451 | ||
8452 | if (state != IF_STATE_ACTION) | |
8453 | goto fail; | |
8454 | ||
8455 | kfree(orig); | |
8456 | ||
8457 | return 0; | |
8458 | ||
8459 | fail_free_name: | |
8460 | kfree(filename); | |
8461 | fail: | |
8462 | free_filters_list(filters); | |
8463 | kfree(orig); | |
8464 | ||
8465 | return ret; | |
8466 | } | |
8467 | ||
8468 | static int | |
8469 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8470 | { | |
8471 | LIST_HEAD(filters); | |
8472 | int ret; | |
8473 | ||
8474 | /* | |
8475 | * Since this is called in perf_ioctl() path, we're already holding | |
8476 | * ctx::mutex. | |
8477 | */ | |
8478 | lockdep_assert_held(&event->ctx->mutex); | |
8479 | ||
8480 | if (WARN_ON_ONCE(event->parent)) | |
8481 | return -EINVAL; | |
8482 | ||
375637bc AS |
8483 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
8484 | if (ret) | |
6ce77bfd | 8485 | goto fail_clear_files; |
375637bc AS |
8486 | |
8487 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
8488 | if (ret) |
8489 | goto fail_free_filters; | |
375637bc AS |
8490 | |
8491 | /* remove existing filters, if any */ | |
8492 | perf_addr_filters_splice(event, &filters); | |
8493 | ||
8494 | /* install new filters */ | |
8495 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8496 | ||
6ce77bfd AS |
8497 | return ret; |
8498 | ||
8499 | fail_free_filters: | |
8500 | free_filters_list(&filters); | |
8501 | ||
8502 | fail_clear_files: | |
8503 | event->addr_filters.nr_file_filters = 0; | |
8504 | ||
375637bc AS |
8505 | return ret; |
8506 | } | |
8507 | ||
c796bbbe AS |
8508 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8509 | { | |
8510 | char *filter_str; | |
8511 | int ret = -EINVAL; | |
8512 | ||
375637bc AS |
8513 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8514 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8515 | !has_addr_filter(event)) | |
c796bbbe AS |
8516 | return -EINVAL; |
8517 | ||
8518 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8519 | if (IS_ERR(filter_str)) | |
8520 | return PTR_ERR(filter_str); | |
8521 | ||
8522 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8523 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8524 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8525 | filter_str); | |
375637bc AS |
8526 | else if (has_addr_filter(event)) |
8527 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8528 | |
8529 | kfree(filter_str); | |
8530 | return ret; | |
8531 | } | |
8532 | ||
b0a873eb PZ |
8533 | /* |
8534 | * hrtimer based swevent callback | |
8535 | */ | |
f29ac756 | 8536 | |
b0a873eb | 8537 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8538 | { |
b0a873eb PZ |
8539 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8540 | struct perf_sample_data data; | |
8541 | struct pt_regs *regs; | |
8542 | struct perf_event *event; | |
8543 | u64 period; | |
f29ac756 | 8544 | |
b0a873eb | 8545 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8546 | |
8547 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8548 | return HRTIMER_NORESTART; | |
8549 | ||
b0a873eb | 8550 | event->pmu->read(event); |
f344011c | 8551 | |
fd0d000b | 8552 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8553 | regs = get_irq_regs(); |
8554 | ||
8555 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8556 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8557 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8558 | ret = HRTIMER_NORESTART; |
8559 | } | |
24f1e32c | 8560 | |
b0a873eb PZ |
8561 | period = max_t(u64, 10000, event->hw.sample_period); |
8562 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8563 | |
b0a873eb | 8564 | return ret; |
f29ac756 PZ |
8565 | } |
8566 | ||
b0a873eb | 8567 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8568 | { |
b0a873eb | 8569 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8570 | s64 period; |
8571 | ||
8572 | if (!is_sampling_event(event)) | |
8573 | return; | |
f5ffe02e | 8574 | |
5d508e82 FBH |
8575 | period = local64_read(&hwc->period_left); |
8576 | if (period) { | |
8577 | if (period < 0) | |
8578 | period = 10000; | |
fa407f35 | 8579 | |
5d508e82 FBH |
8580 | local64_set(&hwc->period_left, 0); |
8581 | } else { | |
8582 | period = max_t(u64, 10000, hwc->sample_period); | |
8583 | } | |
3497d206 TG |
8584 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8585 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8586 | } |
b0a873eb PZ |
8587 | |
8588 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8589 | { |
b0a873eb PZ |
8590 | struct hw_perf_event *hwc = &event->hw; |
8591 | ||
6c7e550f | 8592 | if (is_sampling_event(event)) { |
b0a873eb | 8593 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8594 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8595 | |
8596 | hrtimer_cancel(&hwc->hrtimer); | |
8597 | } | |
24f1e32c FW |
8598 | } |
8599 | ||
ba3dd36c PZ |
8600 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8601 | { | |
8602 | struct hw_perf_event *hwc = &event->hw; | |
8603 | ||
8604 | if (!is_sampling_event(event)) | |
8605 | return; | |
8606 | ||
8607 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8608 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8609 | ||
8610 | /* | |
8611 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8612 | * mapping and avoid the whole period adjust feedback stuff. | |
8613 | */ | |
8614 | if (event->attr.freq) { | |
8615 | long freq = event->attr.sample_freq; | |
8616 | ||
8617 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8618 | hwc->sample_period = event->attr.sample_period; | |
8619 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8620 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8621 | event->attr.freq = 0; |
8622 | } | |
8623 | } | |
8624 | ||
b0a873eb PZ |
8625 | /* |
8626 | * Software event: cpu wall time clock | |
8627 | */ | |
8628 | ||
8629 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8630 | { |
b0a873eb PZ |
8631 | s64 prev; |
8632 | u64 now; | |
8633 | ||
a4eaf7f1 | 8634 | now = local_clock(); |
b0a873eb PZ |
8635 | prev = local64_xchg(&event->hw.prev_count, now); |
8636 | local64_add(now - prev, &event->count); | |
24f1e32c | 8637 | } |
24f1e32c | 8638 | |
a4eaf7f1 | 8639 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8640 | { |
a4eaf7f1 | 8641 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8642 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8643 | } |
8644 | ||
a4eaf7f1 | 8645 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8646 | { |
b0a873eb PZ |
8647 | perf_swevent_cancel_hrtimer(event); |
8648 | cpu_clock_event_update(event); | |
8649 | } | |
f29ac756 | 8650 | |
a4eaf7f1 PZ |
8651 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8652 | { | |
8653 | if (flags & PERF_EF_START) | |
8654 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8655 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8656 | |
8657 | return 0; | |
8658 | } | |
8659 | ||
8660 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8661 | { | |
8662 | cpu_clock_event_stop(event, flags); | |
8663 | } | |
8664 | ||
b0a873eb PZ |
8665 | static void cpu_clock_event_read(struct perf_event *event) |
8666 | { | |
8667 | cpu_clock_event_update(event); | |
8668 | } | |
f344011c | 8669 | |
b0a873eb PZ |
8670 | static int cpu_clock_event_init(struct perf_event *event) |
8671 | { | |
8672 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8673 | return -ENOENT; | |
8674 | ||
8675 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8676 | return -ENOENT; | |
8677 | ||
2481c5fa SE |
8678 | /* |
8679 | * no branch sampling for software events | |
8680 | */ | |
8681 | if (has_branch_stack(event)) | |
8682 | return -EOPNOTSUPP; | |
8683 | ||
ba3dd36c PZ |
8684 | perf_swevent_init_hrtimer(event); |
8685 | ||
b0a873eb | 8686 | return 0; |
f29ac756 PZ |
8687 | } |
8688 | ||
b0a873eb | 8689 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8690 | .task_ctx_nr = perf_sw_context, |
8691 | ||
34f43927 PZ |
8692 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8693 | ||
b0a873eb | 8694 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8695 | .add = cpu_clock_event_add, |
8696 | .del = cpu_clock_event_del, | |
8697 | .start = cpu_clock_event_start, | |
8698 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8699 | .read = cpu_clock_event_read, |
8700 | }; | |
8701 | ||
8702 | /* | |
8703 | * Software event: task time clock | |
8704 | */ | |
8705 | ||
8706 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8707 | { |
b0a873eb PZ |
8708 | u64 prev; |
8709 | s64 delta; | |
5c92d124 | 8710 | |
b0a873eb PZ |
8711 | prev = local64_xchg(&event->hw.prev_count, now); |
8712 | delta = now - prev; | |
8713 | local64_add(delta, &event->count); | |
8714 | } | |
5c92d124 | 8715 | |
a4eaf7f1 | 8716 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8717 | { |
a4eaf7f1 | 8718 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8719 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8720 | } |
8721 | ||
a4eaf7f1 | 8722 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8723 | { |
8724 | perf_swevent_cancel_hrtimer(event); | |
8725 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8726 | } |
8727 | ||
8728 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8729 | { | |
8730 | if (flags & PERF_EF_START) | |
8731 | task_clock_event_start(event, flags); | |
6a694a60 | 8732 | perf_event_update_userpage(event); |
b0a873eb | 8733 | |
a4eaf7f1 PZ |
8734 | return 0; |
8735 | } | |
8736 | ||
8737 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8738 | { | |
8739 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8740 | } |
8741 | ||
8742 | static void task_clock_event_read(struct perf_event *event) | |
8743 | { | |
768a06e2 PZ |
8744 | u64 now = perf_clock(); |
8745 | u64 delta = now - event->ctx->timestamp; | |
8746 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8747 | |
8748 | task_clock_event_update(event, time); | |
8749 | } | |
8750 | ||
8751 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8752 | { |
b0a873eb PZ |
8753 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8754 | return -ENOENT; | |
8755 | ||
8756 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8757 | return -ENOENT; | |
8758 | ||
2481c5fa SE |
8759 | /* |
8760 | * no branch sampling for software events | |
8761 | */ | |
8762 | if (has_branch_stack(event)) | |
8763 | return -EOPNOTSUPP; | |
8764 | ||
ba3dd36c PZ |
8765 | perf_swevent_init_hrtimer(event); |
8766 | ||
b0a873eb | 8767 | return 0; |
6fb2915d LZ |
8768 | } |
8769 | ||
b0a873eb | 8770 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8771 | .task_ctx_nr = perf_sw_context, |
8772 | ||
34f43927 PZ |
8773 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8774 | ||
b0a873eb | 8775 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8776 | .add = task_clock_event_add, |
8777 | .del = task_clock_event_del, | |
8778 | .start = task_clock_event_start, | |
8779 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8780 | .read = task_clock_event_read, |
8781 | }; | |
6fb2915d | 8782 | |
ad5133b7 | 8783 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8784 | { |
e077df4f | 8785 | } |
6fb2915d | 8786 | |
fbbe0701 SB |
8787 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8788 | { | |
8789 | } | |
8790 | ||
ad5133b7 | 8791 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8792 | { |
ad5133b7 | 8793 | return 0; |
6fb2915d LZ |
8794 | } |
8795 | ||
18ab2cd3 | 8796 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8797 | |
8798 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8799 | { |
fbbe0701 SB |
8800 | __this_cpu_write(nop_txn_flags, flags); |
8801 | ||
8802 | if (flags & ~PERF_PMU_TXN_ADD) | |
8803 | return; | |
8804 | ||
ad5133b7 | 8805 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8806 | } |
8807 | ||
ad5133b7 PZ |
8808 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8809 | { | |
fbbe0701 SB |
8810 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8811 | ||
8812 | __this_cpu_write(nop_txn_flags, 0); | |
8813 | ||
8814 | if (flags & ~PERF_PMU_TXN_ADD) | |
8815 | return 0; | |
8816 | ||
ad5133b7 PZ |
8817 | perf_pmu_enable(pmu); |
8818 | return 0; | |
8819 | } | |
e077df4f | 8820 | |
ad5133b7 | 8821 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8822 | { |
fbbe0701 SB |
8823 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8824 | ||
8825 | __this_cpu_write(nop_txn_flags, 0); | |
8826 | ||
8827 | if (flags & ~PERF_PMU_TXN_ADD) | |
8828 | return; | |
8829 | ||
ad5133b7 | 8830 | perf_pmu_enable(pmu); |
24f1e32c FW |
8831 | } |
8832 | ||
35edc2a5 PZ |
8833 | static int perf_event_idx_default(struct perf_event *event) |
8834 | { | |
c719f560 | 8835 | return 0; |
35edc2a5 PZ |
8836 | } |
8837 | ||
8dc85d54 PZ |
8838 | /* |
8839 | * Ensures all contexts with the same task_ctx_nr have the same | |
8840 | * pmu_cpu_context too. | |
8841 | */ | |
9e317041 | 8842 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8843 | { |
8dc85d54 | 8844 | struct pmu *pmu; |
b326e956 | 8845 | |
8dc85d54 PZ |
8846 | if (ctxn < 0) |
8847 | return NULL; | |
24f1e32c | 8848 | |
8dc85d54 PZ |
8849 | list_for_each_entry(pmu, &pmus, entry) { |
8850 | if (pmu->task_ctx_nr == ctxn) | |
8851 | return pmu->pmu_cpu_context; | |
8852 | } | |
24f1e32c | 8853 | |
8dc85d54 | 8854 | return NULL; |
24f1e32c FW |
8855 | } |
8856 | ||
51676957 PZ |
8857 | static void free_pmu_context(struct pmu *pmu) |
8858 | { | |
8dc85d54 | 8859 | mutex_lock(&pmus_lock); |
51676957 | 8860 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 | 8861 | mutex_unlock(&pmus_lock); |
24f1e32c | 8862 | } |
6e855cd4 AS |
8863 | |
8864 | /* | |
8865 | * Let userspace know that this PMU supports address range filtering: | |
8866 | */ | |
8867 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8868 | struct device_attribute *attr, | |
8869 | char *page) | |
8870 | { | |
8871 | struct pmu *pmu = dev_get_drvdata(dev); | |
8872 | ||
8873 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8874 | } | |
8875 | DEVICE_ATTR_RO(nr_addr_filters); | |
8876 | ||
2e80a82a | 8877 | static struct idr pmu_idr; |
d6d020e9 | 8878 | |
abe43400 PZ |
8879 | static ssize_t |
8880 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8881 | { | |
8882 | struct pmu *pmu = dev_get_drvdata(dev); | |
8883 | ||
8884 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8885 | } | |
90826ca7 | 8886 | static DEVICE_ATTR_RO(type); |
abe43400 | 8887 | |
62b85639 SE |
8888 | static ssize_t |
8889 | perf_event_mux_interval_ms_show(struct device *dev, | |
8890 | struct device_attribute *attr, | |
8891 | char *page) | |
8892 | { | |
8893 | struct pmu *pmu = dev_get_drvdata(dev); | |
8894 | ||
8895 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8896 | } | |
8897 | ||
272325c4 PZ |
8898 | static DEFINE_MUTEX(mux_interval_mutex); |
8899 | ||
62b85639 SE |
8900 | static ssize_t |
8901 | perf_event_mux_interval_ms_store(struct device *dev, | |
8902 | struct device_attribute *attr, | |
8903 | const char *buf, size_t count) | |
8904 | { | |
8905 | struct pmu *pmu = dev_get_drvdata(dev); | |
8906 | int timer, cpu, ret; | |
8907 | ||
8908 | ret = kstrtoint(buf, 0, &timer); | |
8909 | if (ret) | |
8910 | return ret; | |
8911 | ||
8912 | if (timer < 1) | |
8913 | return -EINVAL; | |
8914 | ||
8915 | /* same value, noting to do */ | |
8916 | if (timer == pmu->hrtimer_interval_ms) | |
8917 | return count; | |
8918 | ||
272325c4 | 8919 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8920 | pmu->hrtimer_interval_ms = timer; |
8921 | ||
8922 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8923 | get_online_cpus(); |
8924 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8925 | struct perf_cpu_context *cpuctx; |
8926 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8927 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8928 | ||
272325c4 PZ |
8929 | cpu_function_call(cpu, |
8930 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8931 | } |
272325c4 PZ |
8932 | put_online_cpus(); |
8933 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8934 | |
8935 | return count; | |
8936 | } | |
90826ca7 | 8937 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8938 | |
90826ca7 GKH |
8939 | static struct attribute *pmu_dev_attrs[] = { |
8940 | &dev_attr_type.attr, | |
8941 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8942 | NULL, | |
abe43400 | 8943 | }; |
90826ca7 | 8944 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8945 | |
8946 | static int pmu_bus_running; | |
8947 | static struct bus_type pmu_bus = { | |
8948 | .name = "event_source", | |
90826ca7 | 8949 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8950 | }; |
8951 | ||
8952 | static void pmu_dev_release(struct device *dev) | |
8953 | { | |
8954 | kfree(dev); | |
8955 | } | |
8956 | ||
8957 | static int pmu_dev_alloc(struct pmu *pmu) | |
8958 | { | |
8959 | int ret = -ENOMEM; | |
8960 | ||
8961 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8962 | if (!pmu->dev) | |
8963 | goto out; | |
8964 | ||
0c9d42ed | 8965 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8966 | device_initialize(pmu->dev); |
8967 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8968 | if (ret) | |
8969 | goto free_dev; | |
8970 | ||
8971 | dev_set_drvdata(pmu->dev, pmu); | |
8972 | pmu->dev->bus = &pmu_bus; | |
8973 | pmu->dev->release = pmu_dev_release; | |
8974 | ret = device_add(pmu->dev); | |
8975 | if (ret) | |
8976 | goto free_dev; | |
8977 | ||
6e855cd4 AS |
8978 | /* For PMUs with address filters, throw in an extra attribute: */ |
8979 | if (pmu->nr_addr_filters) | |
8980 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8981 | ||
8982 | if (ret) | |
8983 | goto del_dev; | |
8984 | ||
abe43400 PZ |
8985 | out: |
8986 | return ret; | |
8987 | ||
6e855cd4 AS |
8988 | del_dev: |
8989 | device_del(pmu->dev); | |
8990 | ||
abe43400 PZ |
8991 | free_dev: |
8992 | put_device(pmu->dev); | |
8993 | goto out; | |
8994 | } | |
8995 | ||
547e9fd7 | 8996 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8997 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8998 | |
03d8e80b | 8999 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 9000 | { |
108b02cf | 9001 | int cpu, ret; |
24f1e32c | 9002 | |
b0a873eb | 9003 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
9004 | ret = -ENOMEM; |
9005 | pmu->pmu_disable_count = alloc_percpu(int); | |
9006 | if (!pmu->pmu_disable_count) | |
9007 | goto unlock; | |
f29ac756 | 9008 | |
2e80a82a PZ |
9009 | pmu->type = -1; |
9010 | if (!name) | |
9011 | goto skip_type; | |
9012 | pmu->name = name; | |
9013 | ||
9014 | if (type < 0) { | |
0e9c3be2 TH |
9015 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
9016 | if (type < 0) { | |
9017 | ret = type; | |
2e80a82a PZ |
9018 | goto free_pdc; |
9019 | } | |
9020 | } | |
9021 | pmu->type = type; | |
9022 | ||
abe43400 PZ |
9023 | if (pmu_bus_running) { |
9024 | ret = pmu_dev_alloc(pmu); | |
9025 | if (ret) | |
9026 | goto free_idr; | |
9027 | } | |
9028 | ||
2e80a82a | 9029 | skip_type: |
26657848 PZ |
9030 | if (pmu->task_ctx_nr == perf_hw_context) { |
9031 | static int hw_context_taken = 0; | |
9032 | ||
5101ef20 MR |
9033 | /* |
9034 | * Other than systems with heterogeneous CPUs, it never makes | |
9035 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
9036 | * uncore must use perf_invalid_context. | |
9037 | */ | |
9038 | if (WARN_ON_ONCE(hw_context_taken && | |
9039 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
9040 | pmu->task_ctx_nr = perf_invalid_context; |
9041 | ||
9042 | hw_context_taken = 1; | |
9043 | } | |
9044 | ||
8dc85d54 PZ |
9045 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
9046 | if (pmu->pmu_cpu_context) | |
9047 | goto got_cpu_context; | |
f29ac756 | 9048 | |
c4814202 | 9049 | ret = -ENOMEM; |
108b02cf PZ |
9050 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
9051 | if (!pmu->pmu_cpu_context) | |
abe43400 | 9052 | goto free_dev; |
f344011c | 9053 | |
108b02cf PZ |
9054 | for_each_possible_cpu(cpu) { |
9055 | struct perf_cpu_context *cpuctx; | |
9056 | ||
9057 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 9058 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 9059 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 9060 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 9061 | cpuctx->ctx.pmu = pmu; |
9e630205 | 9062 | |
272325c4 | 9063 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 9064 | } |
76e1d904 | 9065 | |
8dc85d54 | 9066 | got_cpu_context: |
ad5133b7 PZ |
9067 | if (!pmu->start_txn) { |
9068 | if (pmu->pmu_enable) { | |
9069 | /* | |
9070 | * If we have pmu_enable/pmu_disable calls, install | |
9071 | * transaction stubs that use that to try and batch | |
9072 | * hardware accesses. | |
9073 | */ | |
9074 | pmu->start_txn = perf_pmu_start_txn; | |
9075 | pmu->commit_txn = perf_pmu_commit_txn; | |
9076 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
9077 | } else { | |
fbbe0701 | 9078 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
9079 | pmu->commit_txn = perf_pmu_nop_int; |
9080 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 9081 | } |
5c92d124 | 9082 | } |
15dbf27c | 9083 | |
ad5133b7 PZ |
9084 | if (!pmu->pmu_enable) { |
9085 | pmu->pmu_enable = perf_pmu_nop_void; | |
9086 | pmu->pmu_disable = perf_pmu_nop_void; | |
9087 | } | |
9088 | ||
35edc2a5 PZ |
9089 | if (!pmu->event_idx) |
9090 | pmu->event_idx = perf_event_idx_default; | |
9091 | ||
b0a873eb | 9092 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 9093 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
9094 | ret = 0; |
9095 | unlock: | |
b0a873eb PZ |
9096 | mutex_unlock(&pmus_lock); |
9097 | ||
33696fc0 | 9098 | return ret; |
108b02cf | 9099 | |
abe43400 PZ |
9100 | free_dev: |
9101 | device_del(pmu->dev); | |
9102 | put_device(pmu->dev); | |
9103 | ||
2e80a82a PZ |
9104 | free_idr: |
9105 | if (pmu->type >= PERF_TYPE_MAX) | |
9106 | idr_remove(&pmu_idr, pmu->type); | |
9107 | ||
108b02cf PZ |
9108 | free_pdc: |
9109 | free_percpu(pmu->pmu_disable_count); | |
9110 | goto unlock; | |
f29ac756 | 9111 | } |
c464c76e | 9112 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 9113 | |
b0a873eb | 9114 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 9115 | { |
0933840a JO |
9116 | int remove_device; |
9117 | ||
b0a873eb | 9118 | mutex_lock(&pmus_lock); |
0933840a | 9119 | remove_device = pmu_bus_running; |
b0a873eb PZ |
9120 | list_del_rcu(&pmu->entry); |
9121 | mutex_unlock(&pmus_lock); | |
5c92d124 | 9122 | |
0475f9ea | 9123 | /* |
cde8e884 PZ |
9124 | * We dereference the pmu list under both SRCU and regular RCU, so |
9125 | * synchronize against both of those. | |
0475f9ea | 9126 | */ |
b0a873eb | 9127 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 9128 | synchronize_rcu(); |
d6d020e9 | 9129 | |
33696fc0 | 9130 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
9131 | if (pmu->type >= PERF_TYPE_MAX) |
9132 | idr_remove(&pmu_idr, pmu->type); | |
0933840a JO |
9133 | if (remove_device) { |
9134 | if (pmu->nr_addr_filters) | |
9135 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9136 | device_del(pmu->dev); | |
9137 | put_device(pmu->dev); | |
9138 | } | |
51676957 | 9139 | free_pmu_context(pmu); |
b0a873eb | 9140 | } |
c464c76e | 9141 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 9142 | |
cc34b98b MR |
9143 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
9144 | { | |
ccd41c86 | 9145 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
9146 | int ret; |
9147 | ||
9148 | if (!try_module_get(pmu->module)) | |
9149 | return -ENODEV; | |
ccd41c86 PZ |
9150 | |
9151 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
9152 | /* |
9153 | * This ctx->mutex can nest when we're called through | |
9154 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
9155 | */ | |
9156 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
9157 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
9158 | BUG_ON(!ctx); |
9159 | } | |
9160 | ||
cc34b98b MR |
9161 | event->pmu = pmu; |
9162 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
9163 | |
9164 | if (ctx) | |
9165 | perf_event_ctx_unlock(event->group_leader, ctx); | |
9166 | ||
cc34b98b MR |
9167 | if (ret) |
9168 | module_put(pmu->module); | |
9169 | ||
9170 | return ret; | |
9171 | } | |
9172 | ||
18ab2cd3 | 9173 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
9174 | { |
9175 | struct pmu *pmu = NULL; | |
9176 | int idx; | |
940c5b29 | 9177 | int ret; |
b0a873eb PZ |
9178 | |
9179 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 9180 | |
40999312 KL |
9181 | /* Try parent's PMU first: */ |
9182 | if (event->parent && event->parent->pmu) { | |
9183 | pmu = event->parent->pmu; | |
9184 | ret = perf_try_init_event(pmu, event); | |
9185 | if (!ret) | |
9186 | goto unlock; | |
9187 | } | |
9188 | ||
2e80a82a PZ |
9189 | rcu_read_lock(); |
9190 | pmu = idr_find(&pmu_idr, event->attr.type); | |
9191 | rcu_read_unlock(); | |
940c5b29 | 9192 | if (pmu) { |
cc34b98b | 9193 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
9194 | if (ret) |
9195 | pmu = ERR_PTR(ret); | |
2e80a82a | 9196 | goto unlock; |
940c5b29 | 9197 | } |
2e80a82a | 9198 | |
b0a873eb | 9199 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 9200 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 9201 | if (!ret) |
e5f4d339 | 9202 | goto unlock; |
76e1d904 | 9203 | |
b0a873eb PZ |
9204 | if (ret != -ENOENT) { |
9205 | pmu = ERR_PTR(ret); | |
e5f4d339 | 9206 | goto unlock; |
f344011c | 9207 | } |
5c92d124 | 9208 | } |
e5f4d339 PZ |
9209 | pmu = ERR_PTR(-ENOENT); |
9210 | unlock: | |
b0a873eb | 9211 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 9212 | |
4aeb0b42 | 9213 | return pmu; |
5c92d124 IM |
9214 | } |
9215 | ||
f2fb6bef KL |
9216 | static void attach_sb_event(struct perf_event *event) |
9217 | { | |
9218 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
9219 | ||
9220 | raw_spin_lock(&pel->lock); | |
9221 | list_add_rcu(&event->sb_list, &pel->list); | |
9222 | raw_spin_unlock(&pel->lock); | |
9223 | } | |
9224 | ||
aab5b71e PZ |
9225 | /* |
9226 | * We keep a list of all !task (and therefore per-cpu) events | |
9227 | * that need to receive side-band records. | |
9228 | * | |
9229 | * This avoids having to scan all the various PMU per-cpu contexts | |
9230 | * looking for them. | |
9231 | */ | |
f2fb6bef KL |
9232 | static void account_pmu_sb_event(struct perf_event *event) |
9233 | { | |
a4f144eb | 9234 | if (is_sb_event(event)) |
f2fb6bef KL |
9235 | attach_sb_event(event); |
9236 | } | |
9237 | ||
4beb31f3 FW |
9238 | static void account_event_cpu(struct perf_event *event, int cpu) |
9239 | { | |
9240 | if (event->parent) | |
9241 | return; | |
9242 | ||
4beb31f3 FW |
9243 | if (is_cgroup_event(event)) |
9244 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9245 | } | |
9246 | ||
555e0c1e FW |
9247 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9248 | static void account_freq_event_nohz(void) | |
9249 | { | |
9250 | #ifdef CONFIG_NO_HZ_FULL | |
9251 | /* Lock so we don't race with concurrent unaccount */ | |
9252 | spin_lock(&nr_freq_lock); | |
9253 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9254 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9255 | spin_unlock(&nr_freq_lock); | |
9256 | #endif | |
9257 | } | |
9258 | ||
9259 | static void account_freq_event(void) | |
9260 | { | |
9261 | if (tick_nohz_full_enabled()) | |
9262 | account_freq_event_nohz(); | |
9263 | else | |
9264 | atomic_inc(&nr_freq_events); | |
9265 | } | |
9266 | ||
9267 | ||
766d6c07 FW |
9268 | static void account_event(struct perf_event *event) |
9269 | { | |
25432ae9 PZ |
9270 | bool inc = false; |
9271 | ||
4beb31f3 FW |
9272 | if (event->parent) |
9273 | return; | |
9274 | ||
766d6c07 | 9275 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9276 | inc = true; |
766d6c07 FW |
9277 | if (event->attr.mmap || event->attr.mmap_data) |
9278 | atomic_inc(&nr_mmap_events); | |
9279 | if (event->attr.comm) | |
9280 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
9281 | if (event->attr.namespaces) |
9282 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
9283 | if (event->attr.task) |
9284 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9285 | if (event->attr.freq) |
9286 | account_freq_event(); | |
45ac1403 AH |
9287 | if (event->attr.context_switch) { |
9288 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9289 | inc = true; |
45ac1403 | 9290 | } |
4beb31f3 | 9291 | if (has_branch_stack(event)) |
25432ae9 | 9292 | inc = true; |
4beb31f3 | 9293 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9294 | inc = true; |
9295 | ||
9107c89e PZ |
9296 | if (inc) { |
9297 | if (atomic_inc_not_zero(&perf_sched_count)) | |
9298 | goto enabled; | |
9299 | ||
9300 | mutex_lock(&perf_sched_mutex); | |
9301 | if (!atomic_read(&perf_sched_count)) { | |
9302 | static_branch_enable(&perf_sched_events); | |
9303 | /* | |
9304 | * Guarantee that all CPUs observe they key change and | |
9305 | * call the perf scheduling hooks before proceeding to | |
9306 | * install events that need them. | |
9307 | */ | |
9308 | synchronize_sched(); | |
9309 | } | |
9310 | /* | |
9311 | * Now that we have waited for the sync_sched(), allow further | |
9312 | * increments to by-pass the mutex. | |
9313 | */ | |
9314 | atomic_inc(&perf_sched_count); | |
9315 | mutex_unlock(&perf_sched_mutex); | |
9316 | } | |
9317 | enabled: | |
4beb31f3 FW |
9318 | |
9319 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9320 | |
9321 | account_pmu_sb_event(event); | |
766d6c07 FW |
9322 | } |
9323 | ||
0793a61d | 9324 | /* |
cdd6c482 | 9325 | * Allocate and initialize a event structure |
0793a61d | 9326 | */ |
cdd6c482 | 9327 | static struct perf_event * |
c3f00c70 | 9328 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9329 | struct task_struct *task, |
9330 | struct perf_event *group_leader, | |
9331 | struct perf_event *parent_event, | |
4dc0da86 | 9332 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9333 | void *context, int cgroup_fd) |
0793a61d | 9334 | { |
51b0fe39 | 9335 | struct pmu *pmu; |
cdd6c482 IM |
9336 | struct perf_event *event; |
9337 | struct hw_perf_event *hwc; | |
90983b16 | 9338 | long err = -EINVAL; |
0793a61d | 9339 | |
66832eb4 ON |
9340 | if ((unsigned)cpu >= nr_cpu_ids) { |
9341 | if (!task || cpu != -1) | |
9342 | return ERR_PTR(-EINVAL); | |
9343 | } | |
9344 | ||
c3f00c70 | 9345 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9346 | if (!event) |
d5d2bc0d | 9347 | return ERR_PTR(-ENOMEM); |
0793a61d | 9348 | |
04289bb9 | 9349 | /* |
cdd6c482 | 9350 | * Single events are their own group leaders, with an |
04289bb9 IM |
9351 | * empty sibling list: |
9352 | */ | |
9353 | if (!group_leader) | |
cdd6c482 | 9354 | group_leader = event; |
04289bb9 | 9355 | |
cdd6c482 IM |
9356 | mutex_init(&event->child_mutex); |
9357 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9358 | |
cdd6c482 IM |
9359 | INIT_LIST_HEAD(&event->group_entry); |
9360 | INIT_LIST_HEAD(&event->event_entry); | |
9361 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 9362 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9363 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9364 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9365 | INIT_HLIST_NODE(&event->hlist_entry); |
9366 | ||
10c6db11 | 9367 | |
cdd6c482 | 9368 | init_waitqueue_head(&event->waitq); |
e360adbe | 9369 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9370 | |
cdd6c482 | 9371 | mutex_init(&event->mmap_mutex); |
375637bc | 9372 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9373 | |
a6fa941d | 9374 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9375 | event->cpu = cpu; |
9376 | event->attr = *attr; | |
9377 | event->group_leader = group_leader; | |
9378 | event->pmu = NULL; | |
cdd6c482 | 9379 | event->oncpu = -1; |
a96bbc16 | 9380 | |
cdd6c482 | 9381 | event->parent = parent_event; |
b84fbc9f | 9382 | |
17cf22c3 | 9383 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9384 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9385 | |
cdd6c482 | 9386 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9387 | |
d580ff86 PZ |
9388 | if (task) { |
9389 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9390 | /* |
50f16a8b PZ |
9391 | * XXX pmu::event_init needs to know what task to account to |
9392 | * and we cannot use the ctx information because we need the | |
9393 | * pmu before we get a ctx. | |
d580ff86 | 9394 | */ |
50f16a8b | 9395 | event->hw.target = task; |
d580ff86 PZ |
9396 | } |
9397 | ||
34f43927 PZ |
9398 | event->clock = &local_clock; |
9399 | if (parent_event) | |
9400 | event->clock = parent_event->clock; | |
9401 | ||
4dc0da86 | 9402 | if (!overflow_handler && parent_event) { |
b326e956 | 9403 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9404 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9405 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9406 | if (overflow_handler == bpf_overflow_handler) { |
9407 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9408 | ||
9409 | if (IS_ERR(prog)) { | |
9410 | err = PTR_ERR(prog); | |
9411 | goto err_ns; | |
9412 | } | |
9413 | event->prog = prog; | |
9414 | event->orig_overflow_handler = | |
9415 | parent_event->orig_overflow_handler; | |
9416 | } | |
9417 | #endif | |
4dc0da86 | 9418 | } |
66832eb4 | 9419 | |
1879445d WN |
9420 | if (overflow_handler) { |
9421 | event->overflow_handler = overflow_handler; | |
9422 | event->overflow_handler_context = context; | |
9ecda41a WN |
9423 | } else if (is_write_backward(event)){ |
9424 | event->overflow_handler = perf_event_output_backward; | |
9425 | event->overflow_handler_context = NULL; | |
1879445d | 9426 | } else { |
9ecda41a | 9427 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9428 | event->overflow_handler_context = NULL; |
9429 | } | |
97eaf530 | 9430 | |
0231bb53 | 9431 | perf_event__state_init(event); |
a86ed508 | 9432 | |
4aeb0b42 | 9433 | pmu = NULL; |
b8e83514 | 9434 | |
cdd6c482 | 9435 | hwc = &event->hw; |
bd2b5b12 | 9436 | hwc->sample_period = attr->sample_period; |
0d48696f | 9437 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9438 | hwc->sample_period = 1; |
eced1dfc | 9439 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9440 | |
e7850595 | 9441 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9442 | |
2023b359 | 9443 | /* |
cdd6c482 | 9444 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 9445 | */ |
3dab77fb | 9446 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 9447 | goto err_ns; |
a46a2300 YZ |
9448 | |
9449 | if (!has_branch_stack(event)) | |
9450 | event->attr.branch_sample_type = 0; | |
2023b359 | 9451 | |
79dff51e MF |
9452 | if (cgroup_fd != -1) { |
9453 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9454 | if (err) | |
9455 | goto err_ns; | |
9456 | } | |
9457 | ||
b0a873eb | 9458 | pmu = perf_init_event(event); |
4aeb0b42 | 9459 | if (!pmu) |
90983b16 FW |
9460 | goto err_ns; |
9461 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 9462 | err = PTR_ERR(pmu); |
90983b16 | 9463 | goto err_ns; |
621a01ea | 9464 | } |
d5d2bc0d | 9465 | |
bed5b25a AS |
9466 | err = exclusive_event_init(event); |
9467 | if (err) | |
9468 | goto err_pmu; | |
9469 | ||
375637bc AS |
9470 | if (has_addr_filter(event)) { |
9471 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9472 | sizeof(unsigned long), | |
9473 | GFP_KERNEL); | |
9474 | if (!event->addr_filters_offs) | |
9475 | goto err_per_task; | |
9476 | ||
9477 | /* force hw sync on the address filters */ | |
9478 | event->addr_filters_gen = 1; | |
9479 | } | |
9480 | ||
cdd6c482 | 9481 | if (!event->parent) { |
927c7a9e | 9482 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9483 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9484 | if (err) |
375637bc | 9485 | goto err_addr_filters; |
d010b332 | 9486 | } |
f344011c | 9487 | } |
9ee318a7 | 9488 | |
927a5570 AS |
9489 | /* symmetric to unaccount_event() in _free_event() */ |
9490 | account_event(event); | |
9491 | ||
cdd6c482 | 9492 | return event; |
90983b16 | 9493 | |
375637bc AS |
9494 | err_addr_filters: |
9495 | kfree(event->addr_filters_offs); | |
9496 | ||
bed5b25a AS |
9497 | err_per_task: |
9498 | exclusive_event_destroy(event); | |
9499 | ||
90983b16 FW |
9500 | err_pmu: |
9501 | if (event->destroy) | |
9502 | event->destroy(event); | |
c464c76e | 9503 | module_put(pmu->module); |
90983b16 | 9504 | err_ns: |
79dff51e MF |
9505 | if (is_cgroup_event(event)) |
9506 | perf_detach_cgroup(event); | |
90983b16 FW |
9507 | if (event->ns) |
9508 | put_pid_ns(event->ns); | |
9509 | kfree(event); | |
9510 | ||
9511 | return ERR_PTR(err); | |
0793a61d TG |
9512 | } |
9513 | ||
cdd6c482 IM |
9514 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9515 | struct perf_event_attr *attr) | |
974802ea | 9516 | { |
974802ea | 9517 | u32 size; |
cdf8073d | 9518 | int ret; |
974802ea PZ |
9519 | |
9520 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9521 | return -EFAULT; | |
9522 | ||
9523 | /* | |
9524 | * zero the full structure, so that a short copy will be nice. | |
9525 | */ | |
9526 | memset(attr, 0, sizeof(*attr)); | |
9527 | ||
9528 | ret = get_user(size, &uattr->size); | |
9529 | if (ret) | |
9530 | return ret; | |
9531 | ||
9532 | if (size > PAGE_SIZE) /* silly large */ | |
9533 | goto err_size; | |
9534 | ||
9535 | if (!size) /* abi compat */ | |
9536 | size = PERF_ATTR_SIZE_VER0; | |
9537 | ||
9538 | if (size < PERF_ATTR_SIZE_VER0) | |
9539 | goto err_size; | |
9540 | ||
9541 | /* | |
9542 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9543 | * ensure all the unknown bits are 0 - i.e. new |
9544 | * user-space does not rely on any kernel feature | |
9545 | * extensions we dont know about yet. | |
974802ea PZ |
9546 | */ |
9547 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9548 | unsigned char __user *addr; |
9549 | unsigned char __user *end; | |
9550 | unsigned char val; | |
974802ea | 9551 | |
cdf8073d IS |
9552 | addr = (void __user *)uattr + sizeof(*attr); |
9553 | end = (void __user *)uattr + size; | |
974802ea | 9554 | |
cdf8073d | 9555 | for (; addr < end; addr++) { |
974802ea PZ |
9556 | ret = get_user(val, addr); |
9557 | if (ret) | |
9558 | return ret; | |
9559 | if (val) | |
9560 | goto err_size; | |
9561 | } | |
b3e62e35 | 9562 | size = sizeof(*attr); |
974802ea PZ |
9563 | } |
9564 | ||
9565 | ret = copy_from_user(attr, uattr, size); | |
9566 | if (ret) | |
9567 | return -EFAULT; | |
9568 | ||
cd757645 | 9569 | if (attr->__reserved_1) |
974802ea PZ |
9570 | return -EINVAL; |
9571 | ||
9572 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9573 | return -EINVAL; | |
9574 | ||
9575 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9576 | return -EINVAL; | |
9577 | ||
bce38cd5 SE |
9578 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9579 | u64 mask = attr->branch_sample_type; | |
9580 | ||
9581 | /* only using defined bits */ | |
9582 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9583 | return -EINVAL; | |
9584 | ||
9585 | /* at least one branch bit must be set */ | |
9586 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9587 | return -EINVAL; | |
9588 | ||
bce38cd5 SE |
9589 | /* propagate priv level, when not set for branch */ |
9590 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9591 | ||
9592 | /* exclude_kernel checked on syscall entry */ | |
9593 | if (!attr->exclude_kernel) | |
9594 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9595 | ||
9596 | if (!attr->exclude_user) | |
9597 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9598 | ||
9599 | if (!attr->exclude_hv) | |
9600 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9601 | /* | |
9602 | * adjust user setting (for HW filter setup) | |
9603 | */ | |
9604 | attr->branch_sample_type = mask; | |
9605 | } | |
e712209a SE |
9606 | /* privileged levels capture (kernel, hv): check permissions */ |
9607 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9608 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9609 | return -EACCES; | |
bce38cd5 | 9610 | } |
4018994f | 9611 | |
c5ebcedb | 9612 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9613 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9614 | if (ret) |
9615 | return ret; | |
9616 | } | |
9617 | ||
9618 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9619 | if (!arch_perf_have_user_stack_dump()) | |
9620 | return -ENOSYS; | |
9621 | ||
9622 | /* | |
9623 | * We have __u32 type for the size, but so far | |
9624 | * we can only use __u16 as maximum due to the | |
9625 | * __u16 sample size limit. | |
9626 | */ | |
9627 | if (attr->sample_stack_user >= USHRT_MAX) | |
9628 | ret = -EINVAL; | |
9629 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9630 | ret = -EINVAL; | |
9631 | } | |
4018994f | 9632 | |
60e2364e SE |
9633 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9634 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9635 | out: |
9636 | return ret; | |
9637 | ||
9638 | err_size: | |
9639 | put_user(sizeof(*attr), &uattr->size); | |
9640 | ret = -E2BIG; | |
9641 | goto out; | |
9642 | } | |
9643 | ||
ac9721f3 PZ |
9644 | static int |
9645 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9646 | { |
b69cf536 | 9647 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9648 | int ret = -EINVAL; |
9649 | ||
ac9721f3 | 9650 | if (!output_event) |
a4be7c27 PZ |
9651 | goto set; |
9652 | ||
ac9721f3 PZ |
9653 | /* don't allow circular references */ |
9654 | if (event == output_event) | |
a4be7c27 PZ |
9655 | goto out; |
9656 | ||
0f139300 PZ |
9657 | /* |
9658 | * Don't allow cross-cpu buffers | |
9659 | */ | |
9660 | if (output_event->cpu != event->cpu) | |
9661 | goto out; | |
9662 | ||
9663 | /* | |
76369139 | 9664 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9665 | */ |
9666 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9667 | goto out; | |
9668 | ||
34f43927 PZ |
9669 | /* |
9670 | * Mixing clocks in the same buffer is trouble you don't need. | |
9671 | */ | |
9672 | if (output_event->clock != event->clock) | |
9673 | goto out; | |
9674 | ||
9ecda41a WN |
9675 | /* |
9676 | * Either writing ring buffer from beginning or from end. | |
9677 | * Mixing is not allowed. | |
9678 | */ | |
9679 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9680 | goto out; | |
9681 | ||
45bfb2e5 PZ |
9682 | /* |
9683 | * If both events generate aux data, they must be on the same PMU | |
9684 | */ | |
9685 | if (has_aux(event) && has_aux(output_event) && | |
9686 | event->pmu != output_event->pmu) | |
9687 | goto out; | |
9688 | ||
a4be7c27 | 9689 | set: |
cdd6c482 | 9690 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9691 | /* Can't redirect output if we've got an active mmap() */ |
9692 | if (atomic_read(&event->mmap_count)) | |
9693 | goto unlock; | |
a4be7c27 | 9694 | |
ac9721f3 | 9695 | if (output_event) { |
76369139 FW |
9696 | /* get the rb we want to redirect to */ |
9697 | rb = ring_buffer_get(output_event); | |
9698 | if (!rb) | |
ac9721f3 | 9699 | goto unlock; |
a4be7c27 PZ |
9700 | } |
9701 | ||
b69cf536 | 9702 | ring_buffer_attach(event, rb); |
9bb5d40c | 9703 | |
a4be7c27 | 9704 | ret = 0; |
ac9721f3 PZ |
9705 | unlock: |
9706 | mutex_unlock(&event->mmap_mutex); | |
9707 | ||
a4be7c27 | 9708 | out: |
a4be7c27 PZ |
9709 | return ret; |
9710 | } | |
9711 | ||
f63a8daa PZ |
9712 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9713 | { | |
9714 | if (b < a) | |
9715 | swap(a, b); | |
9716 | ||
9717 | mutex_lock(a); | |
9718 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9719 | } | |
9720 | ||
34f43927 PZ |
9721 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9722 | { | |
9723 | bool nmi_safe = false; | |
9724 | ||
9725 | switch (clk_id) { | |
9726 | case CLOCK_MONOTONIC: | |
9727 | event->clock = &ktime_get_mono_fast_ns; | |
9728 | nmi_safe = true; | |
9729 | break; | |
9730 | ||
9731 | case CLOCK_MONOTONIC_RAW: | |
9732 | event->clock = &ktime_get_raw_fast_ns; | |
9733 | nmi_safe = true; | |
9734 | break; | |
9735 | ||
9736 | case CLOCK_REALTIME: | |
9737 | event->clock = &ktime_get_real_ns; | |
9738 | break; | |
9739 | ||
9740 | case CLOCK_BOOTTIME: | |
9741 | event->clock = &ktime_get_boot_ns; | |
9742 | break; | |
9743 | ||
9744 | case CLOCK_TAI: | |
9745 | event->clock = &ktime_get_tai_ns; | |
9746 | break; | |
9747 | ||
9748 | default: | |
9749 | return -EINVAL; | |
9750 | } | |
9751 | ||
9752 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9753 | return -EINVAL; | |
9754 | ||
9755 | return 0; | |
9756 | } | |
9757 | ||
321027c1 PZ |
9758 | /* |
9759 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
9760 | * mutexes. | |
9761 | */ | |
9762 | static struct perf_event_context * | |
9763 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
9764 | struct perf_event_context *ctx) | |
9765 | { | |
9766 | struct perf_event_context *gctx; | |
9767 | ||
9768 | again: | |
9769 | rcu_read_lock(); | |
9770 | gctx = READ_ONCE(group_leader->ctx); | |
9771 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
9772 | rcu_read_unlock(); | |
9773 | goto again; | |
9774 | } | |
9775 | rcu_read_unlock(); | |
9776 | ||
9777 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
9778 | ||
9779 | if (group_leader->ctx != gctx) { | |
9780 | mutex_unlock(&ctx->mutex); | |
9781 | mutex_unlock(&gctx->mutex); | |
9782 | put_ctx(gctx); | |
9783 | goto again; | |
9784 | } | |
9785 | ||
9786 | return gctx; | |
9787 | } | |
9788 | ||
0793a61d | 9789 | /** |
cdd6c482 | 9790 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9791 | * |
cdd6c482 | 9792 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9793 | * @pid: target pid |
9f66a381 | 9794 | * @cpu: target cpu |
cdd6c482 | 9795 | * @group_fd: group leader event fd |
0793a61d | 9796 | */ |
cdd6c482 IM |
9797 | SYSCALL_DEFINE5(perf_event_open, |
9798 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9799 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9800 | { |
b04243ef PZ |
9801 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9802 | struct perf_event *event, *sibling; | |
cdd6c482 | 9803 | struct perf_event_attr attr; |
f63a8daa | 9804 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9805 | struct file *event_file = NULL; |
2903ff01 | 9806 | struct fd group = {NULL, 0}; |
38a81da2 | 9807 | struct task_struct *task = NULL; |
89a1e187 | 9808 | struct pmu *pmu; |
ea635c64 | 9809 | int event_fd; |
b04243ef | 9810 | int move_group = 0; |
dc86cabe | 9811 | int err; |
a21b0b35 | 9812 | int f_flags = O_RDWR; |
79dff51e | 9813 | int cgroup_fd = -1; |
0793a61d | 9814 | |
2743a5b0 | 9815 | /* for future expandability... */ |
e5d1367f | 9816 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9817 | return -EINVAL; |
9818 | ||
dc86cabe IM |
9819 | err = perf_copy_attr(attr_uptr, &attr); |
9820 | if (err) | |
9821 | return err; | |
eab656ae | 9822 | |
0764771d PZ |
9823 | if (!attr.exclude_kernel) { |
9824 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9825 | return -EACCES; | |
9826 | } | |
9827 | ||
e4222673 HB |
9828 | if (attr.namespaces) { |
9829 | if (!capable(CAP_SYS_ADMIN)) | |
9830 | return -EACCES; | |
9831 | } | |
9832 | ||
df58ab24 | 9833 | if (attr.freq) { |
cdd6c482 | 9834 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9835 | return -EINVAL; |
0819b2e3 PZ |
9836 | } else { |
9837 | if (attr.sample_period & (1ULL << 63)) | |
9838 | return -EINVAL; | |
df58ab24 PZ |
9839 | } |
9840 | ||
97c79a38 ACM |
9841 | if (!attr.sample_max_stack) |
9842 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9843 | ||
e5d1367f SE |
9844 | /* |
9845 | * In cgroup mode, the pid argument is used to pass the fd | |
9846 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9847 | * designates the cpu on which to monitor threads from that | |
9848 | * cgroup. | |
9849 | */ | |
9850 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9851 | return -EINVAL; | |
9852 | ||
a21b0b35 YD |
9853 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9854 | f_flags |= O_CLOEXEC; | |
9855 | ||
9856 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9857 | if (event_fd < 0) |
9858 | return event_fd; | |
9859 | ||
ac9721f3 | 9860 | if (group_fd != -1) { |
2903ff01 AV |
9861 | err = perf_fget_light(group_fd, &group); |
9862 | if (err) | |
d14b12d7 | 9863 | goto err_fd; |
2903ff01 | 9864 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9865 | if (flags & PERF_FLAG_FD_OUTPUT) |
9866 | output_event = group_leader; | |
9867 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9868 | group_leader = NULL; | |
9869 | } | |
9870 | ||
e5d1367f | 9871 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9872 | task = find_lively_task_by_vpid(pid); |
9873 | if (IS_ERR(task)) { | |
9874 | err = PTR_ERR(task); | |
9875 | goto err_group_fd; | |
9876 | } | |
9877 | } | |
9878 | ||
1f4ee503 PZ |
9879 | if (task && group_leader && |
9880 | group_leader->attr.inherit != attr.inherit) { | |
9881 | err = -EINVAL; | |
9882 | goto err_task; | |
9883 | } | |
9884 | ||
fbfc623f YZ |
9885 | get_online_cpus(); |
9886 | ||
79c9ce57 PZ |
9887 | if (task) { |
9888 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9889 | if (err) | |
9890 | goto err_cpus; | |
9891 | ||
9892 | /* | |
9893 | * Reuse ptrace permission checks for now. | |
9894 | * | |
9895 | * We must hold cred_guard_mutex across this and any potential | |
9896 | * perf_install_in_context() call for this new event to | |
9897 | * serialize against exec() altering our credentials (and the | |
9898 | * perf_event_exit_task() that could imply). | |
9899 | */ | |
9900 | err = -EACCES; | |
9901 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9902 | goto err_cred; | |
9903 | } | |
9904 | ||
79dff51e MF |
9905 | if (flags & PERF_FLAG_PID_CGROUP) |
9906 | cgroup_fd = pid; | |
9907 | ||
4dc0da86 | 9908 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9909 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9910 | if (IS_ERR(event)) { |
9911 | err = PTR_ERR(event); | |
79c9ce57 | 9912 | goto err_cred; |
d14b12d7 SE |
9913 | } |
9914 | ||
53b25335 VW |
9915 | if (is_sampling_event(event)) { |
9916 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9917 | err = -EOPNOTSUPP; |
53b25335 VW |
9918 | goto err_alloc; |
9919 | } | |
9920 | } | |
9921 | ||
89a1e187 PZ |
9922 | /* |
9923 | * Special case software events and allow them to be part of | |
9924 | * any hardware group. | |
9925 | */ | |
9926 | pmu = event->pmu; | |
b04243ef | 9927 | |
34f43927 PZ |
9928 | if (attr.use_clockid) { |
9929 | err = perf_event_set_clock(event, attr.clockid); | |
9930 | if (err) | |
9931 | goto err_alloc; | |
9932 | } | |
9933 | ||
4ff6a8de DCC |
9934 | if (pmu->task_ctx_nr == perf_sw_context) |
9935 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
9936 | ||
b04243ef PZ |
9937 | if (group_leader && |
9938 | (is_software_event(event) != is_software_event(group_leader))) { | |
9939 | if (is_software_event(event)) { | |
9940 | /* | |
9941 | * If event and group_leader are not both a software | |
9942 | * event, and event is, then group leader is not. | |
9943 | * | |
9944 | * Allow the addition of software events to !software | |
9945 | * groups, this is safe because software events never | |
9946 | * fail to schedule. | |
9947 | */ | |
9948 | pmu = group_leader->pmu; | |
9949 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 9950 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
9951 | /* |
9952 | * In case the group is a pure software group, and we | |
9953 | * try to add a hardware event, move the whole group to | |
9954 | * the hardware context. | |
9955 | */ | |
9956 | move_group = 1; | |
9957 | } | |
9958 | } | |
89a1e187 PZ |
9959 | |
9960 | /* | |
9961 | * Get the target context (task or percpu): | |
9962 | */ | |
4af57ef2 | 9963 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9964 | if (IS_ERR(ctx)) { |
9965 | err = PTR_ERR(ctx); | |
c6be5a5c | 9966 | goto err_alloc; |
89a1e187 PZ |
9967 | } |
9968 | ||
bed5b25a AS |
9969 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9970 | err = -EBUSY; | |
9971 | goto err_context; | |
9972 | } | |
9973 | ||
ccff286d | 9974 | /* |
cdd6c482 | 9975 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9976 | */ |
ac9721f3 | 9977 | if (group_leader) { |
dc86cabe | 9978 | err = -EINVAL; |
04289bb9 | 9979 | |
04289bb9 | 9980 | /* |
ccff286d IM |
9981 | * Do not allow a recursive hierarchy (this new sibling |
9982 | * becoming part of another group-sibling): | |
9983 | */ | |
9984 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9985 | goto err_context; |
34f43927 PZ |
9986 | |
9987 | /* All events in a group should have the same clock */ | |
9988 | if (group_leader->clock != event->clock) | |
9989 | goto err_context; | |
9990 | ||
ccff286d IM |
9991 | /* |
9992 | * Do not allow to attach to a group in a different | |
9993 | * task or CPU context: | |
04289bb9 | 9994 | */ |
b04243ef | 9995 | if (move_group) { |
c3c87e77 PZ |
9996 | /* |
9997 | * Make sure we're both on the same task, or both | |
9998 | * per-cpu events. | |
9999 | */ | |
10000 | if (group_leader->ctx->task != ctx->task) | |
10001 | goto err_context; | |
10002 | ||
10003 | /* | |
10004 | * Make sure we're both events for the same CPU; | |
10005 | * grouping events for different CPUs is broken; since | |
10006 | * you can never concurrently schedule them anyhow. | |
10007 | */ | |
10008 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
10009 | goto err_context; |
10010 | } else { | |
10011 | if (group_leader->ctx != ctx) | |
10012 | goto err_context; | |
10013 | } | |
10014 | ||
3b6f9e5c PM |
10015 | /* |
10016 | * Only a group leader can be exclusive or pinned | |
10017 | */ | |
0d48696f | 10018 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 10019 | goto err_context; |
ac9721f3 PZ |
10020 | } |
10021 | ||
10022 | if (output_event) { | |
10023 | err = perf_event_set_output(event, output_event); | |
10024 | if (err) | |
c3f00c70 | 10025 | goto err_context; |
ac9721f3 | 10026 | } |
0793a61d | 10027 | |
a21b0b35 YD |
10028 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
10029 | f_flags); | |
ea635c64 AV |
10030 | if (IS_ERR(event_file)) { |
10031 | err = PTR_ERR(event_file); | |
201c2f85 | 10032 | event_file = NULL; |
c3f00c70 | 10033 | goto err_context; |
ea635c64 | 10034 | } |
9b51f66d | 10035 | |
b04243ef | 10036 | if (move_group) { |
321027c1 PZ |
10037 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
10038 | ||
84c4e620 PZ |
10039 | if (gctx->task == TASK_TOMBSTONE) { |
10040 | err = -ESRCH; | |
10041 | goto err_locked; | |
10042 | } | |
321027c1 PZ |
10043 | |
10044 | /* | |
10045 | * Check if we raced against another sys_perf_event_open() call | |
10046 | * moving the software group underneath us. | |
10047 | */ | |
10048 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
10049 | /* | |
10050 | * If someone moved the group out from under us, check | |
10051 | * if this new event wound up on the same ctx, if so | |
10052 | * its the regular !move_group case, otherwise fail. | |
10053 | */ | |
10054 | if (gctx != ctx) { | |
10055 | err = -EINVAL; | |
10056 | goto err_locked; | |
10057 | } else { | |
10058 | perf_event_ctx_unlock(group_leader, gctx); | |
10059 | move_group = 0; | |
10060 | } | |
10061 | } | |
f55fc2a5 PZ |
10062 | } else { |
10063 | mutex_lock(&ctx->mutex); | |
10064 | } | |
10065 | ||
84c4e620 PZ |
10066 | if (ctx->task == TASK_TOMBSTONE) { |
10067 | err = -ESRCH; | |
10068 | goto err_locked; | |
10069 | } | |
10070 | ||
a723968c PZ |
10071 | if (!perf_event_validate_size(event)) { |
10072 | err = -E2BIG; | |
10073 | goto err_locked; | |
10074 | } | |
10075 | ||
f55fc2a5 PZ |
10076 | /* |
10077 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
10078 | * because we need to serialize with concurrent event creation. | |
10079 | */ | |
10080 | if (!exclusive_event_installable(event, ctx)) { | |
10081 | /* exclusive and group stuff are assumed mutually exclusive */ | |
10082 | WARN_ON_ONCE(move_group); | |
f63a8daa | 10083 | |
f55fc2a5 PZ |
10084 | err = -EBUSY; |
10085 | goto err_locked; | |
10086 | } | |
f63a8daa | 10087 | |
f55fc2a5 PZ |
10088 | WARN_ON_ONCE(ctx->parent_ctx); |
10089 | ||
79c9ce57 PZ |
10090 | /* |
10091 | * This is the point on no return; we cannot fail hereafter. This is | |
10092 | * where we start modifying current state. | |
10093 | */ | |
10094 | ||
f55fc2a5 | 10095 | if (move_group) { |
f63a8daa PZ |
10096 | /* |
10097 | * See perf_event_ctx_lock() for comments on the details | |
10098 | * of swizzling perf_event::ctx. | |
10099 | */ | |
45a0e07a | 10100 | perf_remove_from_context(group_leader, 0); |
279b5165 | 10101 | put_ctx(gctx); |
0231bb53 | 10102 | |
b04243ef PZ |
10103 | list_for_each_entry(sibling, &group_leader->sibling_list, |
10104 | group_entry) { | |
45a0e07a | 10105 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
10106 | put_ctx(gctx); |
10107 | } | |
b04243ef | 10108 | |
f63a8daa PZ |
10109 | /* |
10110 | * Wait for everybody to stop referencing the events through | |
10111 | * the old lists, before installing it on new lists. | |
10112 | */ | |
0cda4c02 | 10113 | synchronize_rcu(); |
f63a8daa | 10114 | |
8f95b435 PZI |
10115 | /* |
10116 | * Install the group siblings before the group leader. | |
10117 | * | |
10118 | * Because a group leader will try and install the entire group | |
10119 | * (through the sibling list, which is still in-tact), we can | |
10120 | * end up with siblings installed in the wrong context. | |
10121 | * | |
10122 | * By installing siblings first we NO-OP because they're not | |
10123 | * reachable through the group lists. | |
10124 | */ | |
b04243ef PZ |
10125 | list_for_each_entry(sibling, &group_leader->sibling_list, |
10126 | group_entry) { | |
8f95b435 | 10127 | perf_event__state_init(sibling); |
9fc81d87 | 10128 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
10129 | get_ctx(ctx); |
10130 | } | |
8f95b435 PZI |
10131 | |
10132 | /* | |
10133 | * Removing from the context ends up with disabled | |
10134 | * event. What we want here is event in the initial | |
10135 | * startup state, ready to be add into new context. | |
10136 | */ | |
10137 | perf_event__state_init(group_leader); | |
10138 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
10139 | get_ctx(ctx); | |
bed5b25a AS |
10140 | } |
10141 | ||
f73e22ab PZ |
10142 | /* |
10143 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
10144 | * that we're serialized against further additions and before | |
10145 | * perf_install_in_context() which is the point the event is active and | |
10146 | * can use these values. | |
10147 | */ | |
10148 | perf_event__header_size(event); | |
10149 | perf_event__id_header_size(event); | |
10150 | ||
78cd2c74 PZ |
10151 | event->owner = current; |
10152 | ||
e2d37cd2 | 10153 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 10154 | perf_unpin_context(ctx); |
f63a8daa | 10155 | |
f55fc2a5 | 10156 | if (move_group) |
321027c1 | 10157 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 10158 | mutex_unlock(&ctx->mutex); |
9b51f66d | 10159 | |
79c9ce57 PZ |
10160 | if (task) { |
10161 | mutex_unlock(&task->signal->cred_guard_mutex); | |
10162 | put_task_struct(task); | |
10163 | } | |
10164 | ||
fbfc623f YZ |
10165 | put_online_cpus(); |
10166 | ||
cdd6c482 IM |
10167 | mutex_lock(¤t->perf_event_mutex); |
10168 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
10169 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 10170 | |
8a49542c PZ |
10171 | /* |
10172 | * Drop the reference on the group_event after placing the | |
10173 | * new event on the sibling_list. This ensures destruction | |
10174 | * of the group leader will find the pointer to itself in | |
10175 | * perf_group_detach(). | |
10176 | */ | |
2903ff01 | 10177 | fdput(group); |
ea635c64 AV |
10178 | fd_install(event_fd, event_file); |
10179 | return event_fd; | |
0793a61d | 10180 | |
f55fc2a5 PZ |
10181 | err_locked: |
10182 | if (move_group) | |
321027c1 | 10183 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
10184 | mutex_unlock(&ctx->mutex); |
10185 | /* err_file: */ | |
10186 | fput(event_file); | |
c3f00c70 | 10187 | err_context: |
fe4b04fa | 10188 | perf_unpin_context(ctx); |
ea635c64 | 10189 | put_ctx(ctx); |
c6be5a5c | 10190 | err_alloc: |
13005627 PZ |
10191 | /* |
10192 | * If event_file is set, the fput() above will have called ->release() | |
10193 | * and that will take care of freeing the event. | |
10194 | */ | |
10195 | if (!event_file) | |
10196 | free_event(event); | |
79c9ce57 PZ |
10197 | err_cred: |
10198 | if (task) | |
10199 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 10200 | err_cpus: |
fbfc623f | 10201 | put_online_cpus(); |
1f4ee503 | 10202 | err_task: |
e7d0bc04 PZ |
10203 | if (task) |
10204 | put_task_struct(task); | |
89a1e187 | 10205 | err_group_fd: |
2903ff01 | 10206 | fdput(group); |
ea635c64 AV |
10207 | err_fd: |
10208 | put_unused_fd(event_fd); | |
dc86cabe | 10209 | return err; |
0793a61d TG |
10210 | } |
10211 | ||
fb0459d7 AV |
10212 | /** |
10213 | * perf_event_create_kernel_counter | |
10214 | * | |
10215 | * @attr: attributes of the counter to create | |
10216 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 10217 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
10218 | */ |
10219 | struct perf_event * | |
10220 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 10221 | struct task_struct *task, |
4dc0da86 AK |
10222 | perf_overflow_handler_t overflow_handler, |
10223 | void *context) | |
fb0459d7 | 10224 | { |
fb0459d7 | 10225 | struct perf_event_context *ctx; |
c3f00c70 | 10226 | struct perf_event *event; |
fb0459d7 | 10227 | int err; |
d859e29f | 10228 | |
fb0459d7 AV |
10229 | /* |
10230 | * Get the target context (task or percpu): | |
10231 | */ | |
d859e29f | 10232 | |
4dc0da86 | 10233 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10234 | overflow_handler, context, -1); |
c3f00c70 PZ |
10235 | if (IS_ERR(event)) { |
10236 | err = PTR_ERR(event); | |
10237 | goto err; | |
10238 | } | |
d859e29f | 10239 | |
f8697762 | 10240 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10241 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10242 | |
4af57ef2 | 10243 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10244 | if (IS_ERR(ctx)) { |
10245 | err = PTR_ERR(ctx); | |
c3f00c70 | 10246 | goto err_free; |
d859e29f | 10247 | } |
fb0459d7 | 10248 | |
fb0459d7 AV |
10249 | WARN_ON_ONCE(ctx->parent_ctx); |
10250 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10251 | if (ctx->task == TASK_TOMBSTONE) { |
10252 | err = -ESRCH; | |
10253 | goto err_unlock; | |
10254 | } | |
10255 | ||
bed5b25a | 10256 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10257 | err = -EBUSY; |
84c4e620 | 10258 | goto err_unlock; |
bed5b25a AS |
10259 | } |
10260 | ||
fb0459d7 | 10261 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 10262 | perf_unpin_context(ctx); |
fb0459d7 AV |
10263 | mutex_unlock(&ctx->mutex); |
10264 | ||
fb0459d7 AV |
10265 | return event; |
10266 | ||
84c4e620 PZ |
10267 | err_unlock: |
10268 | mutex_unlock(&ctx->mutex); | |
10269 | perf_unpin_context(ctx); | |
10270 | put_ctx(ctx); | |
c3f00c70 PZ |
10271 | err_free: |
10272 | free_event(event); | |
10273 | err: | |
c6567f64 | 10274 | return ERR_PTR(err); |
9b51f66d | 10275 | } |
fb0459d7 | 10276 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10277 | |
0cda4c02 YZ |
10278 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10279 | { | |
10280 | struct perf_event_context *src_ctx; | |
10281 | struct perf_event_context *dst_ctx; | |
10282 | struct perf_event *event, *tmp; | |
10283 | LIST_HEAD(events); | |
10284 | ||
10285 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10286 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10287 | ||
f63a8daa PZ |
10288 | /* |
10289 | * See perf_event_ctx_lock() for comments on the details | |
10290 | * of swizzling perf_event::ctx. | |
10291 | */ | |
10292 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10293 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10294 | event_entry) { | |
45a0e07a | 10295 | perf_remove_from_context(event, 0); |
9a545de0 | 10296 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10297 | put_ctx(src_ctx); |
9886167d | 10298 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10299 | } |
0cda4c02 | 10300 | |
8f95b435 PZI |
10301 | /* |
10302 | * Wait for the events to quiesce before re-instating them. | |
10303 | */ | |
0cda4c02 YZ |
10304 | synchronize_rcu(); |
10305 | ||
8f95b435 PZI |
10306 | /* |
10307 | * Re-instate events in 2 passes. | |
10308 | * | |
10309 | * Skip over group leaders and only install siblings on this first | |
10310 | * pass, siblings will not get enabled without a leader, however a | |
10311 | * leader will enable its siblings, even if those are still on the old | |
10312 | * context. | |
10313 | */ | |
10314 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10315 | if (event->group_leader == event) | |
10316 | continue; | |
10317 | ||
10318 | list_del(&event->migrate_entry); | |
10319 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10320 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10321 | account_event_cpu(event, dst_cpu); | |
10322 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10323 | get_ctx(dst_ctx); | |
10324 | } | |
10325 | ||
10326 | /* | |
10327 | * Once all the siblings are setup properly, install the group leaders | |
10328 | * to make it go. | |
10329 | */ | |
9886167d PZ |
10330 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10331 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10332 | if (event->state >= PERF_EVENT_STATE_OFF) |
10333 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10334 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10335 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10336 | get_ctx(dst_ctx); | |
10337 | } | |
10338 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10339 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10340 | } |
10341 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10342 | ||
cdd6c482 | 10343 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10344 | struct task_struct *child) |
d859e29f | 10345 | { |
cdd6c482 | 10346 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10347 | u64 child_val; |
d859e29f | 10348 | |
cdd6c482 IM |
10349 | if (child_event->attr.inherit_stat) |
10350 | perf_event_read_event(child_event, child); | |
38b200d6 | 10351 | |
b5e58793 | 10352 | child_val = perf_event_count(child_event); |
d859e29f PM |
10353 | |
10354 | /* | |
10355 | * Add back the child's count to the parent's count: | |
10356 | */ | |
a6e6dea6 | 10357 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10358 | atomic64_add(child_event->total_time_enabled, |
10359 | &parent_event->child_total_time_enabled); | |
10360 | atomic64_add(child_event->total_time_running, | |
10361 | &parent_event->child_total_time_running); | |
d859e29f PM |
10362 | } |
10363 | ||
9b51f66d | 10364 | static void |
8ba289b8 PZ |
10365 | perf_event_exit_event(struct perf_event *child_event, |
10366 | struct perf_event_context *child_ctx, | |
10367 | struct task_struct *child) | |
9b51f66d | 10368 | { |
8ba289b8 PZ |
10369 | struct perf_event *parent_event = child_event->parent; |
10370 | ||
1903d50c PZ |
10371 | /* |
10372 | * Do not destroy the 'original' grouping; because of the context | |
10373 | * switch optimization the original events could've ended up in a | |
10374 | * random child task. | |
10375 | * | |
10376 | * If we were to destroy the original group, all group related | |
10377 | * operations would cease to function properly after this random | |
10378 | * child dies. | |
10379 | * | |
10380 | * Do destroy all inherited groups, we don't care about those | |
10381 | * and being thorough is better. | |
10382 | */ | |
32132a3d PZ |
10383 | raw_spin_lock_irq(&child_ctx->lock); |
10384 | WARN_ON_ONCE(child_ctx->is_active); | |
10385 | ||
8ba289b8 | 10386 | if (parent_event) |
32132a3d PZ |
10387 | perf_group_detach(child_event); |
10388 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 10389 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 10390 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10391 | |
9b51f66d | 10392 | /* |
8ba289b8 | 10393 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10394 | */ |
8ba289b8 | 10395 | if (!parent_event) { |
179033b3 | 10396 | perf_event_wakeup(child_event); |
8ba289b8 | 10397 | return; |
4bcf349a | 10398 | } |
8ba289b8 PZ |
10399 | /* |
10400 | * Child events can be cleaned up. | |
10401 | */ | |
10402 | ||
10403 | sync_child_event(child_event, child); | |
10404 | ||
10405 | /* | |
10406 | * Remove this event from the parent's list | |
10407 | */ | |
10408 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10409 | mutex_lock(&parent_event->child_mutex); | |
10410 | list_del_init(&child_event->child_list); | |
10411 | mutex_unlock(&parent_event->child_mutex); | |
10412 | ||
10413 | /* | |
10414 | * Kick perf_poll() for is_event_hup(). | |
10415 | */ | |
10416 | perf_event_wakeup(parent_event); | |
10417 | free_event(child_event); | |
10418 | put_event(parent_event); | |
9b51f66d IM |
10419 | } |
10420 | ||
8dc85d54 | 10421 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10422 | { |
211de6eb | 10423 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10424 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10425 | |
10426 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10427 | |
6a3351b6 | 10428 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10429 | if (!child_ctx) |
9b51f66d IM |
10430 | return; |
10431 | ||
ad3a37de | 10432 | /* |
6a3351b6 PZ |
10433 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10434 | * ctx::mutex over the entire thing. This serializes against almost | |
10435 | * everything that wants to access the ctx. | |
10436 | * | |
10437 | * The exception is sys_perf_event_open() / | |
10438 | * perf_event_create_kernel_count() which does find_get_context() | |
10439 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10440 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10441 | */ |
6a3351b6 | 10442 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10443 | |
10444 | /* | |
6a3351b6 PZ |
10445 | * In a single ctx::lock section, de-schedule the events and detach the |
10446 | * context from the task such that we cannot ever get it scheduled back | |
10447 | * in. | |
c93f7669 | 10448 | */ |
6a3351b6 | 10449 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 10450 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 10451 | |
71a851b4 | 10452 | /* |
63b6da39 PZ |
10453 | * Now that the context is inactive, destroy the task <-> ctx relation |
10454 | * and mark the context dead. | |
71a851b4 | 10455 | */ |
63b6da39 PZ |
10456 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10457 | put_ctx(child_ctx); /* cannot be last */ | |
10458 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10459 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10460 | |
211de6eb | 10461 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10462 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10463 | |
211de6eb PZ |
10464 | if (clone_ctx) |
10465 | put_ctx(clone_ctx); | |
4a1c0f26 | 10466 | |
9f498cc5 | 10467 | /* |
cdd6c482 IM |
10468 | * Report the task dead after unscheduling the events so that we |
10469 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10470 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10471 | */ |
cdd6c482 | 10472 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10473 | |
ebf905fc | 10474 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10475 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10476 | |
a63eaf34 PM |
10477 | mutex_unlock(&child_ctx->mutex); |
10478 | ||
10479 | put_ctx(child_ctx); | |
9b51f66d IM |
10480 | } |
10481 | ||
8dc85d54 PZ |
10482 | /* |
10483 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10484 | * |
10485 | * Can be called with cred_guard_mutex held when called from | |
10486 | * install_exec_creds(). | |
8dc85d54 PZ |
10487 | */ |
10488 | void perf_event_exit_task(struct task_struct *child) | |
10489 | { | |
8882135b | 10490 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10491 | int ctxn; |
10492 | ||
8882135b PZ |
10493 | mutex_lock(&child->perf_event_mutex); |
10494 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10495 | owner_entry) { | |
10496 | list_del_init(&event->owner_entry); | |
10497 | ||
10498 | /* | |
10499 | * Ensure the list deletion is visible before we clear | |
10500 | * the owner, closes a race against perf_release() where | |
10501 | * we need to serialize on the owner->perf_event_mutex. | |
10502 | */ | |
f47c02c0 | 10503 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10504 | } |
10505 | mutex_unlock(&child->perf_event_mutex); | |
10506 | ||
8dc85d54 PZ |
10507 | for_each_task_context_nr(ctxn) |
10508 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10509 | |
10510 | /* | |
10511 | * The perf_event_exit_task_context calls perf_event_task | |
10512 | * with child's task_ctx, which generates EXIT events for | |
10513 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10514 | * At this point we need to send EXIT events to cpu contexts. | |
10515 | */ | |
10516 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10517 | } |
10518 | ||
889ff015 FW |
10519 | static void perf_free_event(struct perf_event *event, |
10520 | struct perf_event_context *ctx) | |
10521 | { | |
10522 | struct perf_event *parent = event->parent; | |
10523 | ||
10524 | if (WARN_ON_ONCE(!parent)) | |
10525 | return; | |
10526 | ||
10527 | mutex_lock(&parent->child_mutex); | |
10528 | list_del_init(&event->child_list); | |
10529 | mutex_unlock(&parent->child_mutex); | |
10530 | ||
a6fa941d | 10531 | put_event(parent); |
889ff015 | 10532 | |
652884fe | 10533 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10534 | perf_group_detach(event); |
889ff015 | 10535 | list_del_event(event, ctx); |
652884fe | 10536 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10537 | free_event(event); |
10538 | } | |
10539 | ||
bbbee908 | 10540 | /* |
652884fe | 10541 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10542 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10543 | * |
10544 | * Not all locks are strictly required, but take them anyway to be nice and | |
10545 | * help out with the lockdep assertions. | |
bbbee908 | 10546 | */ |
cdd6c482 | 10547 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10548 | { |
8dc85d54 | 10549 | struct perf_event_context *ctx; |
cdd6c482 | 10550 | struct perf_event *event, *tmp; |
8dc85d54 | 10551 | int ctxn; |
bbbee908 | 10552 | |
8dc85d54 PZ |
10553 | for_each_task_context_nr(ctxn) { |
10554 | ctx = task->perf_event_ctxp[ctxn]; | |
10555 | if (!ctx) | |
10556 | continue; | |
bbbee908 | 10557 | |
8dc85d54 | 10558 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
10559 | raw_spin_lock_irq(&ctx->lock); |
10560 | /* | |
10561 | * Destroy the task <-> ctx relation and mark the context dead. | |
10562 | * | |
10563 | * This is important because even though the task hasn't been | |
10564 | * exposed yet the context has been (through child_list). | |
10565 | */ | |
10566 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
10567 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
10568 | put_task_struct(task); /* cannot be last */ | |
10569 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 10570 | |
15121c78 | 10571 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 10572 | perf_free_event(event, ctx); |
bbbee908 | 10573 | |
8dc85d54 | 10574 | mutex_unlock(&ctx->mutex); |
8dc85d54 PZ |
10575 | put_ctx(ctx); |
10576 | } | |
889ff015 FW |
10577 | } |
10578 | ||
4e231c79 PZ |
10579 | void perf_event_delayed_put(struct task_struct *task) |
10580 | { | |
10581 | int ctxn; | |
10582 | ||
10583 | for_each_task_context_nr(ctxn) | |
10584 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10585 | } | |
10586 | ||
e03e7ee3 | 10587 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10588 | { |
e03e7ee3 | 10589 | struct file *file; |
ffe8690c | 10590 | |
e03e7ee3 AS |
10591 | file = fget_raw(fd); |
10592 | if (!file) | |
10593 | return ERR_PTR(-EBADF); | |
ffe8690c | 10594 | |
e03e7ee3 AS |
10595 | if (file->f_op != &perf_fops) { |
10596 | fput(file); | |
10597 | return ERR_PTR(-EBADF); | |
10598 | } | |
ffe8690c | 10599 | |
e03e7ee3 | 10600 | return file; |
ffe8690c KX |
10601 | } |
10602 | ||
10603 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10604 | { | |
10605 | if (!event) | |
10606 | return ERR_PTR(-EINVAL); | |
10607 | ||
10608 | return &event->attr; | |
10609 | } | |
10610 | ||
97dee4f3 | 10611 | /* |
d8a8cfc7 PZ |
10612 | * Inherit a event from parent task to child task. |
10613 | * | |
10614 | * Returns: | |
10615 | * - valid pointer on success | |
10616 | * - NULL for orphaned events | |
10617 | * - IS_ERR() on error | |
97dee4f3 PZ |
10618 | */ |
10619 | static struct perf_event * | |
10620 | inherit_event(struct perf_event *parent_event, | |
10621 | struct task_struct *parent, | |
10622 | struct perf_event_context *parent_ctx, | |
10623 | struct task_struct *child, | |
10624 | struct perf_event *group_leader, | |
10625 | struct perf_event_context *child_ctx) | |
10626 | { | |
1929def9 | 10627 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10628 | struct perf_event *child_event; |
cee010ec | 10629 | unsigned long flags; |
97dee4f3 PZ |
10630 | |
10631 | /* | |
10632 | * Instead of creating recursive hierarchies of events, | |
10633 | * we link inherited events back to the original parent, | |
10634 | * which has a filp for sure, which we use as the reference | |
10635 | * count: | |
10636 | */ | |
10637 | if (parent_event->parent) | |
10638 | parent_event = parent_event->parent; | |
10639 | ||
10640 | child_event = perf_event_alloc(&parent_event->attr, | |
10641 | parent_event->cpu, | |
d580ff86 | 10642 | child, |
97dee4f3 | 10643 | group_leader, parent_event, |
79dff51e | 10644 | NULL, NULL, -1); |
97dee4f3 PZ |
10645 | if (IS_ERR(child_event)) |
10646 | return child_event; | |
a6fa941d | 10647 | |
c6e5b732 PZ |
10648 | /* |
10649 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10650 | * must be under the same lock in order to serialize against | |
10651 | * perf_event_release_kernel(), such that either we must observe | |
10652 | * is_orphaned_event() or they will observe us on the child_list. | |
10653 | */ | |
10654 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10655 | if (is_orphaned_event(parent_event) || |
10656 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10657 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10658 | free_event(child_event); |
10659 | return NULL; | |
10660 | } | |
10661 | ||
97dee4f3 PZ |
10662 | get_ctx(child_ctx); |
10663 | ||
10664 | /* | |
10665 | * Make the child state follow the state of the parent event, | |
10666 | * not its attr.disabled bit. We hold the parent's mutex, | |
10667 | * so we won't race with perf_event_{en, dis}able_family. | |
10668 | */ | |
1929def9 | 10669 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10670 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10671 | else | |
10672 | child_event->state = PERF_EVENT_STATE_OFF; | |
10673 | ||
10674 | if (parent_event->attr.freq) { | |
10675 | u64 sample_period = parent_event->hw.sample_period; | |
10676 | struct hw_perf_event *hwc = &child_event->hw; | |
10677 | ||
10678 | hwc->sample_period = sample_period; | |
10679 | hwc->last_period = sample_period; | |
10680 | ||
10681 | local64_set(&hwc->period_left, sample_period); | |
10682 | } | |
10683 | ||
10684 | child_event->ctx = child_ctx; | |
10685 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10686 | child_event->overflow_handler_context |
10687 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10688 | |
614b6780 TG |
10689 | /* |
10690 | * Precalculate sample_data sizes | |
10691 | */ | |
10692 | perf_event__header_size(child_event); | |
6844c09d | 10693 | perf_event__id_header_size(child_event); |
614b6780 | 10694 | |
97dee4f3 PZ |
10695 | /* |
10696 | * Link it up in the child's context: | |
10697 | */ | |
cee010ec | 10698 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10699 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10700 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10701 | |
97dee4f3 PZ |
10702 | /* |
10703 | * Link this into the parent event's child list | |
10704 | */ | |
97dee4f3 PZ |
10705 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10706 | mutex_unlock(&parent_event->child_mutex); | |
10707 | ||
10708 | return child_event; | |
10709 | } | |
10710 | ||
d8a8cfc7 PZ |
10711 | /* |
10712 | * Inherits an event group. | |
10713 | * | |
10714 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
10715 | * This matches with perf_event_release_kernel() removing all child events. | |
10716 | * | |
10717 | * Returns: | |
10718 | * - 0 on success | |
10719 | * - <0 on error | |
10720 | */ | |
97dee4f3 PZ |
10721 | static int inherit_group(struct perf_event *parent_event, |
10722 | struct task_struct *parent, | |
10723 | struct perf_event_context *parent_ctx, | |
10724 | struct task_struct *child, | |
10725 | struct perf_event_context *child_ctx) | |
10726 | { | |
10727 | struct perf_event *leader; | |
10728 | struct perf_event *sub; | |
10729 | struct perf_event *child_ctr; | |
10730 | ||
10731 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10732 | child, NULL, child_ctx); | |
10733 | if (IS_ERR(leader)) | |
10734 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
10735 | /* |
10736 | * @leader can be NULL here because of is_orphaned_event(). In this | |
10737 | * case inherit_event() will create individual events, similar to what | |
10738 | * perf_group_detach() would do anyway. | |
10739 | */ | |
97dee4f3 PZ |
10740 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { |
10741 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10742 | child, leader, child_ctx); | |
10743 | if (IS_ERR(child_ctr)) | |
10744 | return PTR_ERR(child_ctr); | |
10745 | } | |
10746 | return 0; | |
889ff015 FW |
10747 | } |
10748 | ||
d8a8cfc7 PZ |
10749 | /* |
10750 | * Creates the child task context and tries to inherit the event-group. | |
10751 | * | |
10752 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
10753 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
10754 | * consistent with perf_event_release_kernel() removing all child events. | |
10755 | * | |
10756 | * Returns: | |
10757 | * - 0 on success | |
10758 | * - <0 on error | |
10759 | */ | |
889ff015 FW |
10760 | static int |
10761 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10762 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10763 | struct task_struct *child, int ctxn, |
889ff015 FW |
10764 | int *inherited_all) |
10765 | { | |
10766 | int ret; | |
8dc85d54 | 10767 | struct perf_event_context *child_ctx; |
889ff015 FW |
10768 | |
10769 | if (!event->attr.inherit) { | |
10770 | *inherited_all = 0; | |
10771 | return 0; | |
bbbee908 PZ |
10772 | } |
10773 | ||
fe4b04fa | 10774 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10775 | if (!child_ctx) { |
10776 | /* | |
10777 | * This is executed from the parent task context, so | |
10778 | * inherit events that have been marked for cloning. | |
10779 | * First allocate and initialize a context for the | |
10780 | * child. | |
10781 | */ | |
734df5ab | 10782 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10783 | if (!child_ctx) |
10784 | return -ENOMEM; | |
bbbee908 | 10785 | |
8dc85d54 | 10786 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10787 | } |
10788 | ||
10789 | ret = inherit_group(event, parent, parent_ctx, | |
10790 | child, child_ctx); | |
10791 | ||
10792 | if (ret) | |
10793 | *inherited_all = 0; | |
10794 | ||
10795 | return ret; | |
bbbee908 PZ |
10796 | } |
10797 | ||
9b51f66d | 10798 | /* |
cdd6c482 | 10799 | * Initialize the perf_event context in task_struct |
9b51f66d | 10800 | */ |
985c8dcb | 10801 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10802 | { |
889ff015 | 10803 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10804 | struct perf_event_context *cloned_ctx; |
10805 | struct perf_event *event; | |
9b51f66d | 10806 | struct task_struct *parent = current; |
564c2b21 | 10807 | int inherited_all = 1; |
dddd3379 | 10808 | unsigned long flags; |
6ab423e0 | 10809 | int ret = 0; |
9b51f66d | 10810 | |
8dc85d54 | 10811 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10812 | return 0; |
10813 | ||
ad3a37de | 10814 | /* |
25346b93 PM |
10815 | * If the parent's context is a clone, pin it so it won't get |
10816 | * swapped under us. | |
ad3a37de | 10817 | */ |
8dc85d54 | 10818 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10819 | if (!parent_ctx) |
10820 | return 0; | |
25346b93 | 10821 | |
ad3a37de PM |
10822 | /* |
10823 | * No need to check if parent_ctx != NULL here; since we saw | |
10824 | * it non-NULL earlier, the only reason for it to become NULL | |
10825 | * is if we exit, and since we're currently in the middle of | |
10826 | * a fork we can't be exiting at the same time. | |
10827 | */ | |
ad3a37de | 10828 | |
9b51f66d IM |
10829 | /* |
10830 | * Lock the parent list. No need to lock the child - not PID | |
10831 | * hashed yet and not running, so nobody can access it. | |
10832 | */ | |
d859e29f | 10833 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10834 | |
10835 | /* | |
10836 | * We dont have to disable NMIs - we are only looking at | |
10837 | * the list, not manipulating it: | |
10838 | */ | |
889ff015 | 10839 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10840 | ret = inherit_task_group(event, parent, parent_ctx, |
10841 | child, ctxn, &inherited_all); | |
889ff015 | 10842 | if (ret) |
e7cc4865 | 10843 | goto out_unlock; |
889ff015 | 10844 | } |
b93f7978 | 10845 | |
dddd3379 TG |
10846 | /* |
10847 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10848 | * to allocations, but we need to prevent rotation because | |
10849 | * rotate_ctx() will change the list from interrupt context. | |
10850 | */ | |
10851 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10852 | parent_ctx->rotate_disable = 1; | |
10853 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10854 | ||
889ff015 | 10855 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10856 | ret = inherit_task_group(event, parent, parent_ctx, |
10857 | child, ctxn, &inherited_all); | |
889ff015 | 10858 | if (ret) |
e7cc4865 | 10859 | goto out_unlock; |
564c2b21 PM |
10860 | } |
10861 | ||
dddd3379 TG |
10862 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10863 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10864 | |
8dc85d54 | 10865 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10866 | |
05cbaa28 | 10867 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10868 | /* |
10869 | * Mark the child context as a clone of the parent | |
10870 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10871 | * |
10872 | * Note that if the parent is a clone, the holding of | |
10873 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10874 | */ |
c5ed5145 | 10875 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10876 | if (cloned_ctx) { |
10877 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10878 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10879 | } else { |
10880 | child_ctx->parent_ctx = parent_ctx; | |
10881 | child_ctx->parent_gen = parent_ctx->generation; | |
10882 | } | |
10883 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10884 | } |
10885 | ||
c5ed5145 | 10886 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 10887 | out_unlock: |
d859e29f | 10888 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10889 | |
25346b93 | 10890 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10891 | put_ctx(parent_ctx); |
ad3a37de | 10892 | |
6ab423e0 | 10893 | return ret; |
9b51f66d IM |
10894 | } |
10895 | ||
8dc85d54 PZ |
10896 | /* |
10897 | * Initialize the perf_event context in task_struct | |
10898 | */ | |
10899 | int perf_event_init_task(struct task_struct *child) | |
10900 | { | |
10901 | int ctxn, ret; | |
10902 | ||
8550d7cb ON |
10903 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10904 | mutex_init(&child->perf_event_mutex); | |
10905 | INIT_LIST_HEAD(&child->perf_event_list); | |
10906 | ||
8dc85d54 PZ |
10907 | for_each_task_context_nr(ctxn) { |
10908 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10909 | if (ret) { |
10910 | perf_event_free_task(child); | |
8dc85d54 | 10911 | return ret; |
6c72e350 | 10912 | } |
8dc85d54 PZ |
10913 | } |
10914 | ||
10915 | return 0; | |
10916 | } | |
10917 | ||
220b140b PM |
10918 | static void __init perf_event_init_all_cpus(void) |
10919 | { | |
b28ab83c | 10920 | struct swevent_htable *swhash; |
220b140b | 10921 | int cpu; |
220b140b PM |
10922 | |
10923 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10924 | swhash = &per_cpu(swevent_htable, cpu); |
10925 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10926 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10927 | |
10928 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10929 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 10930 | |
058fe1c0 DCC |
10931 | #ifdef CONFIG_CGROUP_PERF |
10932 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
10933 | #endif | |
e48c1788 | 10934 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
10935 | } |
10936 | } | |
10937 | ||
00e16c3d | 10938 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10939 | { |
108b02cf | 10940 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10941 | |
b28ab83c | 10942 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10943 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10944 | struct swevent_hlist *hlist; |
10945 | ||
b28ab83c PZ |
10946 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10947 | WARN_ON(!hlist); | |
10948 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10949 | } |
b28ab83c | 10950 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10951 | return 0; |
0793a61d TG |
10952 | } |
10953 | ||
2965faa5 | 10954 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10955 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10956 | { |
108b02cf | 10957 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10958 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10959 | struct perf_event *event; | |
0793a61d | 10960 | |
fae3fde6 PZ |
10961 | raw_spin_lock(&ctx->lock); |
10962 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10963 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10964 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10965 | } |
108b02cf PZ |
10966 | |
10967 | static void perf_event_exit_cpu_context(int cpu) | |
10968 | { | |
10969 | struct perf_event_context *ctx; | |
10970 | struct pmu *pmu; | |
10971 | int idx; | |
10972 | ||
10973 | idx = srcu_read_lock(&pmus_srcu); | |
10974 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10975 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10976 | |
10977 | mutex_lock(&ctx->mutex); | |
10978 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10979 | mutex_unlock(&ctx->mutex); | |
10980 | } | |
10981 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10982 | } |
00e16c3d TG |
10983 | #else |
10984 | ||
10985 | static void perf_event_exit_cpu_context(int cpu) { } | |
10986 | ||
10987 | #endif | |
108b02cf | 10988 | |
00e16c3d | 10989 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10990 | { |
e3703f8c | 10991 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10992 | return 0; |
0793a61d | 10993 | } |
0793a61d | 10994 | |
c277443c PZ |
10995 | static int |
10996 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10997 | { | |
10998 | int cpu; | |
10999 | ||
11000 | for_each_online_cpu(cpu) | |
11001 | perf_event_exit_cpu(cpu); | |
11002 | ||
11003 | return NOTIFY_OK; | |
11004 | } | |
11005 | ||
11006 | /* | |
11007 | * Run the perf reboot notifier at the very last possible moment so that | |
11008 | * the generic watchdog code runs as long as possible. | |
11009 | */ | |
11010 | static struct notifier_block perf_reboot_notifier = { | |
11011 | .notifier_call = perf_reboot, | |
11012 | .priority = INT_MIN, | |
11013 | }; | |
11014 | ||
cdd6c482 | 11015 | void __init perf_event_init(void) |
0793a61d | 11016 | { |
3c502e7a JW |
11017 | int ret; |
11018 | ||
2e80a82a PZ |
11019 | idr_init(&pmu_idr); |
11020 | ||
220b140b | 11021 | perf_event_init_all_cpus(); |
b0a873eb | 11022 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
11023 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
11024 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
11025 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 11026 | perf_tp_register(); |
00e16c3d | 11027 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 11028 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
11029 | |
11030 | ret = init_hw_breakpoint(); | |
11031 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 11032 | |
b01c3a00 JO |
11033 | /* |
11034 | * Build time assertion that we keep the data_head at the intended | |
11035 | * location. IOW, validation we got the __reserved[] size right. | |
11036 | */ | |
11037 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
11038 | != 1024); | |
0793a61d | 11039 | } |
abe43400 | 11040 | |
fd979c01 CS |
11041 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
11042 | char *page) | |
11043 | { | |
11044 | struct perf_pmu_events_attr *pmu_attr = | |
11045 | container_of(attr, struct perf_pmu_events_attr, attr); | |
11046 | ||
11047 | if (pmu_attr->event_str) | |
11048 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
11049 | ||
11050 | return 0; | |
11051 | } | |
675965b0 | 11052 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 11053 | |
abe43400 PZ |
11054 | static int __init perf_event_sysfs_init(void) |
11055 | { | |
11056 | struct pmu *pmu; | |
11057 | int ret; | |
11058 | ||
11059 | mutex_lock(&pmus_lock); | |
11060 | ||
11061 | ret = bus_register(&pmu_bus); | |
11062 | if (ret) | |
11063 | goto unlock; | |
11064 | ||
11065 | list_for_each_entry(pmu, &pmus, entry) { | |
11066 | if (!pmu->name || pmu->type < 0) | |
11067 | continue; | |
11068 | ||
11069 | ret = pmu_dev_alloc(pmu); | |
11070 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
11071 | } | |
11072 | pmu_bus_running = 1; | |
11073 | ret = 0; | |
11074 | ||
11075 | unlock: | |
11076 | mutex_unlock(&pmus_lock); | |
11077 | ||
11078 | return ret; | |
11079 | } | |
11080 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
11081 | |
11082 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
11083 | static struct cgroup_subsys_state * |
11084 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
11085 | { |
11086 | struct perf_cgroup *jc; | |
e5d1367f | 11087 | |
1b15d055 | 11088 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
11089 | if (!jc) |
11090 | return ERR_PTR(-ENOMEM); | |
11091 | ||
e5d1367f SE |
11092 | jc->info = alloc_percpu(struct perf_cgroup_info); |
11093 | if (!jc->info) { | |
11094 | kfree(jc); | |
11095 | return ERR_PTR(-ENOMEM); | |
11096 | } | |
11097 | ||
e5d1367f SE |
11098 | return &jc->css; |
11099 | } | |
11100 | ||
eb95419b | 11101 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 11102 | { |
eb95419b TH |
11103 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
11104 | ||
e5d1367f SE |
11105 | free_percpu(jc->info); |
11106 | kfree(jc); | |
11107 | } | |
11108 | ||
11109 | static int __perf_cgroup_move(void *info) | |
11110 | { | |
11111 | struct task_struct *task = info; | |
ddaaf4e2 | 11112 | rcu_read_lock(); |
e5d1367f | 11113 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 11114 | rcu_read_unlock(); |
e5d1367f SE |
11115 | return 0; |
11116 | } | |
11117 | ||
1f7dd3e5 | 11118 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 11119 | { |
bb9d97b6 | 11120 | struct task_struct *task; |
1f7dd3e5 | 11121 | struct cgroup_subsys_state *css; |
bb9d97b6 | 11122 | |
1f7dd3e5 | 11123 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 11124 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
11125 | } |
11126 | ||
073219e9 | 11127 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
11128 | .css_alloc = perf_cgroup_css_alloc, |
11129 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 11130 | .attach = perf_cgroup_attach, |
968ebff1 TH |
11131 | /* |
11132 | * Implicitly enable on dfl hierarchy so that perf events can | |
11133 | * always be filtered by cgroup2 path as long as perf_event | |
11134 | * controller is not mounted on a legacy hierarchy. | |
11135 | */ | |
11136 | .implicit_on_dfl = true, | |
e5d1367f SE |
11137 | }; |
11138 | #endif /* CONFIG_CGROUP_PERF */ |