Commit | Line | Data |
---|---|---|
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 | 211 | |
16444645 | 212 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 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 | ||
16444645 | 309 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
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; | |
a63fbed7 | 392 | static cpumask_var_t perf_online_mask; |
108b02cf | 393 | |
0764771d | 394 | /* |
cdd6c482 | 395 | * perf event paranoia level: |
0fbdea19 IM |
396 | * -1 - not paranoid at all |
397 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 398 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 399 | * 2 - disallow kernel profiling for unpriv |
0764771d | 400 | */ |
0161028b | 401 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 402 | |
20443384 FW |
403 | /* Minimum for 512 kiB + 1 user control page */ |
404 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
405 | |
406 | /* | |
cdd6c482 | 407 | * max perf event sample rate |
df58ab24 | 408 | */ |
14c63f17 DH |
409 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
410 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
411 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
412 | ||
413 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
414 | ||
415 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
416 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
417 | ||
d9494cb4 PZ |
418 | static int perf_sample_allowed_ns __read_mostly = |
419 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 420 | |
18ab2cd3 | 421 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
422 | { |
423 | u64 tmp = perf_sample_period_ns; | |
424 | ||
425 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
426 | tmp = div_u64(tmp, 100); |
427 | if (!tmp) | |
428 | tmp = 1; | |
429 | ||
430 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 431 | } |
163ec435 | 432 | |
8d5bce0c | 433 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 434 | |
163ec435 PZ |
435 | int perf_proc_update_handler(struct ctl_table *table, int write, |
436 | void __user *buffer, size_t *lenp, | |
437 | loff_t *ppos) | |
438 | { | |
723478c8 | 439 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
440 | |
441 | if (ret || !write) | |
442 | return ret; | |
443 | ||
ab7fdefb KL |
444 | /* |
445 | * If throttling is disabled don't allow the write: | |
446 | */ | |
447 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
448 | sysctl_perf_cpu_time_max_percent == 0) | |
449 | return -EINVAL; | |
450 | ||
163ec435 | 451 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
452 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
453 | update_perf_cpu_limits(); | |
454 | ||
455 | return 0; | |
456 | } | |
457 | ||
458 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
459 | ||
460 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
461 | void __user *buffer, size_t *lenp, | |
462 | loff_t *ppos) | |
463 | { | |
1572e45a | 464 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
465 | |
466 | if (ret || !write) | |
467 | return ret; | |
468 | ||
b303e7c1 PZ |
469 | if (sysctl_perf_cpu_time_max_percent == 100 || |
470 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
471 | printk(KERN_WARNING |
472 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
473 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
474 | } else { | |
475 | update_perf_cpu_limits(); | |
476 | } | |
163ec435 PZ |
477 | |
478 | return 0; | |
479 | } | |
1ccd1549 | 480 | |
14c63f17 DH |
481 | /* |
482 | * perf samples are done in some very critical code paths (NMIs). | |
483 | * If they take too much CPU time, the system can lock up and not | |
484 | * get any real work done. This will drop the sample rate when | |
485 | * we detect that events are taking too long. | |
486 | */ | |
487 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 488 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 489 | |
91a612ee PZ |
490 | static u64 __report_avg; |
491 | static u64 __report_allowed; | |
492 | ||
6a02ad66 | 493 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 494 | { |
0d87d7ec | 495 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
496 | "perf: interrupt took too long (%lld > %lld), lowering " |
497 | "kernel.perf_event_max_sample_rate to %d\n", | |
498 | __report_avg, __report_allowed, | |
499 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
500 | } |
501 | ||
502 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
503 | ||
504 | void perf_sample_event_took(u64 sample_len_ns) | |
505 | { | |
91a612ee PZ |
506 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
507 | u64 running_len; | |
508 | u64 avg_len; | |
509 | u32 max; | |
14c63f17 | 510 | |
91a612ee | 511 | if (max_len == 0) |
14c63f17 DH |
512 | return; |
513 | ||
91a612ee PZ |
514 | /* Decay the counter by 1 average sample. */ |
515 | running_len = __this_cpu_read(running_sample_length); | |
516 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
517 | running_len += sample_len_ns; | |
518 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
519 | |
520 | /* | |
91a612ee PZ |
521 | * Note: this will be biased artifically low until we have |
522 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
523 | * from having to maintain a count. |
524 | */ | |
91a612ee PZ |
525 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
526 | if (avg_len <= max_len) | |
14c63f17 DH |
527 | return; |
528 | ||
91a612ee PZ |
529 | __report_avg = avg_len; |
530 | __report_allowed = max_len; | |
14c63f17 | 531 | |
91a612ee PZ |
532 | /* |
533 | * Compute a throttle threshold 25% below the current duration. | |
534 | */ | |
535 | avg_len += avg_len / 4; | |
536 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
537 | if (avg_len < max) | |
538 | max /= (u32)avg_len; | |
539 | else | |
540 | max = 1; | |
14c63f17 | 541 | |
91a612ee PZ |
542 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
543 | WRITE_ONCE(max_samples_per_tick, max); | |
544 | ||
545 | sysctl_perf_event_sample_rate = max * HZ; | |
546 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 547 | |
cd578abb | 548 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 549 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 550 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 551 | __report_avg, __report_allowed, |
cd578abb PZ |
552 | sysctl_perf_event_sample_rate); |
553 | } | |
14c63f17 DH |
554 | } |
555 | ||
cdd6c482 | 556 | static atomic64_t perf_event_id; |
a96bbc16 | 557 | |
0b3fcf17 SE |
558 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
559 | enum event_type_t event_type); | |
560 | ||
561 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
562 | enum event_type_t event_type, |
563 | struct task_struct *task); | |
564 | ||
565 | static void update_context_time(struct perf_event_context *ctx); | |
566 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 567 | |
cdd6c482 | 568 | void __weak perf_event_print_debug(void) { } |
0793a61d | 569 | |
84c79910 | 570 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 571 | { |
84c79910 | 572 | return "pmu"; |
0793a61d TG |
573 | } |
574 | ||
0b3fcf17 SE |
575 | static inline u64 perf_clock(void) |
576 | { | |
577 | return local_clock(); | |
578 | } | |
579 | ||
34f43927 PZ |
580 | static inline u64 perf_event_clock(struct perf_event *event) |
581 | { | |
582 | return event->clock(); | |
583 | } | |
584 | ||
0d3d73aa PZ |
585 | /* |
586 | * State based event timekeeping... | |
587 | * | |
588 | * The basic idea is to use event->state to determine which (if any) time | |
589 | * fields to increment with the current delta. This means we only need to | |
590 | * update timestamps when we change state or when they are explicitly requested | |
591 | * (read). | |
592 | * | |
593 | * Event groups make things a little more complicated, but not terribly so. The | |
594 | * rules for a group are that if the group leader is OFF the entire group is | |
595 | * OFF, irrespecive of what the group member states are. This results in | |
596 | * __perf_effective_state(). | |
597 | * | |
598 | * A futher ramification is that when a group leader flips between OFF and | |
599 | * !OFF, we need to update all group member times. | |
600 | * | |
601 | * | |
602 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
603 | * need to make sure the relevant context time is updated before we try and | |
604 | * update our timestamps. | |
605 | */ | |
606 | ||
607 | static __always_inline enum perf_event_state | |
608 | __perf_effective_state(struct perf_event *event) | |
609 | { | |
610 | struct perf_event *leader = event->group_leader; | |
611 | ||
612 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
613 | return leader->state; | |
614 | ||
615 | return event->state; | |
616 | } | |
617 | ||
618 | static __always_inline void | |
619 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
620 | { | |
621 | enum perf_event_state state = __perf_effective_state(event); | |
622 | u64 delta = now - event->tstamp; | |
623 | ||
624 | *enabled = event->total_time_enabled; | |
625 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
626 | *enabled += delta; | |
627 | ||
628 | *running = event->total_time_running; | |
629 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
630 | *running += delta; | |
631 | } | |
632 | ||
633 | static void perf_event_update_time(struct perf_event *event) | |
634 | { | |
635 | u64 now = perf_event_time(event); | |
636 | ||
637 | __perf_update_times(event, now, &event->total_time_enabled, | |
638 | &event->total_time_running); | |
639 | event->tstamp = now; | |
640 | } | |
641 | ||
642 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
643 | { | |
644 | struct perf_event *sibling; | |
645 | ||
8343aae6 | 646 | list_for_each_entry(sibling, &leader->sibling_list, sibling_list) |
0d3d73aa PZ |
647 | perf_event_update_time(sibling); |
648 | } | |
649 | ||
650 | static void | |
651 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
652 | { | |
653 | if (event->state == state) | |
654 | return; | |
655 | ||
656 | perf_event_update_time(event); | |
657 | /* | |
658 | * If a group leader gets enabled/disabled all its siblings | |
659 | * are affected too. | |
660 | */ | |
661 | if ((event->state < 0) ^ (state < 0)) | |
662 | perf_event_update_sibling_time(event); | |
663 | ||
664 | WRITE_ONCE(event->state, state); | |
665 | } | |
666 | ||
e5d1367f SE |
667 | #ifdef CONFIG_CGROUP_PERF |
668 | ||
e5d1367f SE |
669 | static inline bool |
670 | perf_cgroup_match(struct perf_event *event) | |
671 | { | |
672 | struct perf_event_context *ctx = event->ctx; | |
673 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
674 | ||
ef824fa1 TH |
675 | /* @event doesn't care about cgroup */ |
676 | if (!event->cgrp) | |
677 | return true; | |
678 | ||
679 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
680 | if (!cpuctx->cgrp) | |
681 | return false; | |
682 | ||
683 | /* | |
684 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
685 | * also enabled for all its descendant cgroups. If @cpuctx's | |
686 | * cgroup is a descendant of @event's (the test covers identity | |
687 | * case), it's a match. | |
688 | */ | |
689 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
690 | event->cgrp->css.cgroup); | |
e5d1367f SE |
691 | } |
692 | ||
e5d1367f SE |
693 | static inline void perf_detach_cgroup(struct perf_event *event) |
694 | { | |
4e2ba650 | 695 | css_put(&event->cgrp->css); |
e5d1367f SE |
696 | event->cgrp = NULL; |
697 | } | |
698 | ||
699 | static inline int is_cgroup_event(struct perf_event *event) | |
700 | { | |
701 | return event->cgrp != NULL; | |
702 | } | |
703 | ||
704 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
705 | { | |
706 | struct perf_cgroup_info *t; | |
707 | ||
708 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
709 | return t->time; | |
710 | } | |
711 | ||
712 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
713 | { | |
714 | struct perf_cgroup_info *info; | |
715 | u64 now; | |
716 | ||
717 | now = perf_clock(); | |
718 | ||
719 | info = this_cpu_ptr(cgrp->info); | |
720 | ||
721 | info->time += now - info->timestamp; | |
722 | info->timestamp = now; | |
723 | } | |
724 | ||
725 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
726 | { | |
727 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
728 | if (cgrp_out) | |
729 | __update_cgrp_time(cgrp_out); | |
730 | } | |
731 | ||
732 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
733 | { | |
3f7cce3c SE |
734 | struct perf_cgroup *cgrp; |
735 | ||
e5d1367f | 736 | /* |
3f7cce3c SE |
737 | * ensure we access cgroup data only when needed and |
738 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 739 | */ |
3f7cce3c | 740 | if (!is_cgroup_event(event)) |
e5d1367f SE |
741 | return; |
742 | ||
614e4c4e | 743 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
744 | /* |
745 | * Do not update time when cgroup is not active | |
746 | */ | |
e6a52033 | 747 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 748 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
749 | } |
750 | ||
751 | static inline void | |
3f7cce3c SE |
752 | perf_cgroup_set_timestamp(struct task_struct *task, |
753 | struct perf_event_context *ctx) | |
e5d1367f SE |
754 | { |
755 | struct perf_cgroup *cgrp; | |
756 | struct perf_cgroup_info *info; | |
757 | ||
3f7cce3c SE |
758 | /* |
759 | * ctx->lock held by caller | |
760 | * ensure we do not access cgroup data | |
761 | * unless we have the cgroup pinned (css_get) | |
762 | */ | |
763 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
764 | return; |
765 | ||
614e4c4e | 766 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 767 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 768 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
769 | } |
770 | ||
058fe1c0 DCC |
771 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
772 | ||
e5d1367f SE |
773 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
774 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
775 | ||
776 | /* | |
777 | * reschedule events based on the cgroup constraint of task. | |
778 | * | |
779 | * mode SWOUT : schedule out everything | |
780 | * mode SWIN : schedule in based on cgroup for next | |
781 | */ | |
18ab2cd3 | 782 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
783 | { |
784 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 785 | struct list_head *list; |
e5d1367f SE |
786 | unsigned long flags; |
787 | ||
788 | /* | |
058fe1c0 DCC |
789 | * Disable interrupts and preemption to avoid this CPU's |
790 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
791 | */ |
792 | local_irq_save(flags); | |
793 | ||
058fe1c0 DCC |
794 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
795 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
796 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 797 | |
058fe1c0 DCC |
798 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
799 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 800 | |
058fe1c0 DCC |
801 | if (mode & PERF_CGROUP_SWOUT) { |
802 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
803 | /* | |
804 | * must not be done before ctxswout due | |
805 | * to event_filter_match() in event_sched_out() | |
806 | */ | |
807 | cpuctx->cgrp = NULL; | |
808 | } | |
e5d1367f | 809 | |
058fe1c0 DCC |
810 | if (mode & PERF_CGROUP_SWIN) { |
811 | WARN_ON_ONCE(cpuctx->cgrp); | |
812 | /* | |
813 | * set cgrp before ctxsw in to allow | |
814 | * event_filter_match() to not have to pass | |
815 | * task around | |
816 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
817 | * because cgorup events are only per-cpu | |
818 | */ | |
819 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
820 | &cpuctx->ctx); | |
821 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 822 | } |
058fe1c0 DCC |
823 | perf_pmu_enable(cpuctx->ctx.pmu); |
824 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
825 | } |
826 | ||
e5d1367f SE |
827 | local_irq_restore(flags); |
828 | } | |
829 | ||
a8d757ef SE |
830 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
831 | struct task_struct *next) | |
e5d1367f | 832 | { |
a8d757ef SE |
833 | struct perf_cgroup *cgrp1; |
834 | struct perf_cgroup *cgrp2 = NULL; | |
835 | ||
ddaaf4e2 | 836 | rcu_read_lock(); |
a8d757ef SE |
837 | /* |
838 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
839 | * we do not need to pass the ctx here because we know |
840 | * we are holding the rcu lock | |
a8d757ef | 841 | */ |
614e4c4e | 842 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 843 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
844 | |
845 | /* | |
846 | * only schedule out current cgroup events if we know | |
847 | * that we are switching to a different cgroup. Otherwise, | |
848 | * do no touch the cgroup events. | |
849 | */ | |
850 | if (cgrp1 != cgrp2) | |
851 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
852 | |
853 | rcu_read_unlock(); | |
e5d1367f SE |
854 | } |
855 | ||
a8d757ef SE |
856 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
857 | struct task_struct *task) | |
e5d1367f | 858 | { |
a8d757ef SE |
859 | struct perf_cgroup *cgrp1; |
860 | struct perf_cgroup *cgrp2 = NULL; | |
861 | ||
ddaaf4e2 | 862 | rcu_read_lock(); |
a8d757ef SE |
863 | /* |
864 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
865 | * we do not need to pass the ctx here because we know |
866 | * we are holding the rcu lock | |
a8d757ef | 867 | */ |
614e4c4e | 868 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 869 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
870 | |
871 | /* | |
872 | * only need to schedule in cgroup events if we are changing | |
873 | * cgroup during ctxsw. Cgroup events were not scheduled | |
874 | * out of ctxsw out if that was not the case. | |
875 | */ | |
876 | if (cgrp1 != cgrp2) | |
877 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
878 | |
879 | rcu_read_unlock(); | |
e5d1367f SE |
880 | } |
881 | ||
882 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
883 | struct perf_event_attr *attr, | |
884 | struct perf_event *group_leader) | |
885 | { | |
886 | struct perf_cgroup *cgrp; | |
887 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
888 | struct fd f = fdget(fd); |
889 | int ret = 0; | |
e5d1367f | 890 | |
2903ff01 | 891 | if (!f.file) |
e5d1367f SE |
892 | return -EBADF; |
893 | ||
b583043e | 894 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 895 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
896 | if (IS_ERR(css)) { |
897 | ret = PTR_ERR(css); | |
898 | goto out; | |
899 | } | |
e5d1367f SE |
900 | |
901 | cgrp = container_of(css, struct perf_cgroup, css); | |
902 | event->cgrp = cgrp; | |
903 | ||
904 | /* | |
905 | * all events in a group must monitor | |
906 | * the same cgroup because a task belongs | |
907 | * to only one perf cgroup at a time | |
908 | */ | |
909 | if (group_leader && group_leader->cgrp != cgrp) { | |
910 | perf_detach_cgroup(event); | |
911 | ret = -EINVAL; | |
e5d1367f | 912 | } |
3db272c0 | 913 | out: |
2903ff01 | 914 | fdput(f); |
e5d1367f SE |
915 | return ret; |
916 | } | |
917 | ||
918 | static inline void | |
919 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
920 | { | |
921 | struct perf_cgroup_info *t; | |
922 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
923 | event->shadow_ctx_time = now - t->timestamp; | |
924 | } | |
925 | ||
db4a8356 DCC |
926 | /* |
927 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
928 | * cleared when last cgroup event is removed. | |
929 | */ | |
930 | static inline void | |
931 | list_update_cgroup_event(struct perf_event *event, | |
932 | struct perf_event_context *ctx, bool add) | |
933 | { | |
934 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 935 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
936 | |
937 | if (!is_cgroup_event(event)) | |
938 | return; | |
939 | ||
940 | if (add && ctx->nr_cgroups++) | |
941 | return; | |
942 | else if (!add && --ctx->nr_cgroups) | |
943 | return; | |
944 | /* | |
945 | * Because cgroup events are always per-cpu events, | |
946 | * this will always be called from the right CPU. | |
947 | */ | |
948 | cpuctx = __get_cpu_context(ctx); | |
058fe1c0 DCC |
949 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; |
950 | /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/ | |
951 | if (add) { | |
be96b316 TH |
952 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
953 | ||
058fe1c0 | 954 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); |
be96b316 TH |
955 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
956 | cpuctx->cgrp = cgrp; | |
058fe1c0 DCC |
957 | } else { |
958 | list_del(cpuctx_entry); | |
8fc31ce8 | 959 | cpuctx->cgrp = NULL; |
058fe1c0 | 960 | } |
db4a8356 DCC |
961 | } |
962 | ||
e5d1367f SE |
963 | #else /* !CONFIG_CGROUP_PERF */ |
964 | ||
965 | static inline bool | |
966 | perf_cgroup_match(struct perf_event *event) | |
967 | { | |
968 | return true; | |
969 | } | |
970 | ||
971 | static inline void perf_detach_cgroup(struct perf_event *event) | |
972 | {} | |
973 | ||
974 | static inline int is_cgroup_event(struct perf_event *event) | |
975 | { | |
976 | return 0; | |
977 | } | |
978 | ||
e5d1367f SE |
979 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
980 | { | |
981 | } | |
982 | ||
983 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
984 | { | |
985 | } | |
986 | ||
a8d757ef SE |
987 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
988 | struct task_struct *next) | |
e5d1367f SE |
989 | { |
990 | } | |
991 | ||
a8d757ef SE |
992 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
993 | struct task_struct *task) | |
e5d1367f SE |
994 | { |
995 | } | |
996 | ||
997 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
998 | struct perf_event_attr *attr, | |
999 | struct perf_event *group_leader) | |
1000 | { | |
1001 | return -EINVAL; | |
1002 | } | |
1003 | ||
1004 | static inline void | |
3f7cce3c SE |
1005 | perf_cgroup_set_timestamp(struct task_struct *task, |
1006 | struct perf_event_context *ctx) | |
e5d1367f SE |
1007 | { |
1008 | } | |
1009 | ||
1010 | void | |
1011 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
1012 | { | |
1013 | } | |
1014 | ||
1015 | static inline void | |
1016 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1017 | { | |
1018 | } | |
1019 | ||
1020 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1021 | { | |
1022 | return 0; | |
1023 | } | |
1024 | ||
db4a8356 DCC |
1025 | static inline void |
1026 | list_update_cgroup_event(struct perf_event *event, | |
1027 | struct perf_event_context *ctx, bool add) | |
1028 | { | |
1029 | } | |
1030 | ||
e5d1367f SE |
1031 | #endif |
1032 | ||
9e630205 SE |
1033 | /* |
1034 | * set default to be dependent on timer tick just | |
1035 | * like original code | |
1036 | */ | |
1037 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1038 | /* | |
8a1115ff | 1039 | * function must be called with interrupts disabled |
9e630205 | 1040 | */ |
272325c4 | 1041 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1042 | { |
1043 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1044 | bool rotations; |
9e630205 | 1045 | |
16444645 | 1046 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1047 | |
1048 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1049 | rotations = perf_rotate_context(cpuctx); |
1050 | ||
4cfafd30 PZ |
1051 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1052 | if (rotations) | |
9e630205 | 1053 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1054 | else |
1055 | cpuctx->hrtimer_active = 0; | |
1056 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1057 | |
4cfafd30 | 1058 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1059 | } |
1060 | ||
272325c4 | 1061 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1062 | { |
272325c4 | 1063 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1064 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1065 | u64 interval; |
9e630205 SE |
1066 | |
1067 | /* no multiplexing needed for SW PMU */ | |
1068 | if (pmu->task_ctx_nr == perf_sw_context) | |
1069 | return; | |
1070 | ||
62b85639 SE |
1071 | /* |
1072 | * check default is sane, if not set then force to | |
1073 | * default interval (1/tick) | |
1074 | */ | |
272325c4 PZ |
1075 | interval = pmu->hrtimer_interval_ms; |
1076 | if (interval < 1) | |
1077 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1078 | |
272325c4 | 1079 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1080 | |
4cfafd30 PZ |
1081 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1082 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1083 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1084 | } |
1085 | ||
272325c4 | 1086 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1087 | { |
272325c4 | 1088 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1089 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1090 | unsigned long flags; |
9e630205 SE |
1091 | |
1092 | /* not for SW PMU */ | |
1093 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1094 | return 0; |
9e630205 | 1095 | |
4cfafd30 PZ |
1096 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1097 | if (!cpuctx->hrtimer_active) { | |
1098 | cpuctx->hrtimer_active = 1; | |
1099 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1100 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1101 | } | |
1102 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1103 | |
272325c4 | 1104 | return 0; |
9e630205 SE |
1105 | } |
1106 | ||
33696fc0 | 1107 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1108 | { |
33696fc0 PZ |
1109 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1110 | if (!(*count)++) | |
1111 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1112 | } |
9e35ad38 | 1113 | |
33696fc0 | 1114 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1115 | { |
33696fc0 PZ |
1116 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1117 | if (!--(*count)) | |
1118 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1119 | } |
9e35ad38 | 1120 | |
2fde4f94 | 1121 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1122 | |
1123 | /* | |
2fde4f94 MR |
1124 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1125 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1126 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1127 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1128 | */ |
2fde4f94 | 1129 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1130 | { |
2fde4f94 | 1131 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1132 | |
16444645 | 1133 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1134 | |
2fde4f94 MR |
1135 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1136 | ||
1137 | list_add(&ctx->active_ctx_list, head); | |
1138 | } | |
1139 | ||
1140 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1141 | { | |
16444645 | 1142 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1143 | |
1144 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1145 | ||
1146 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1147 | } |
9e35ad38 | 1148 | |
cdd6c482 | 1149 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1150 | { |
e5289d4a | 1151 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1152 | } |
1153 | ||
4af57ef2 YZ |
1154 | static void free_ctx(struct rcu_head *head) |
1155 | { | |
1156 | struct perf_event_context *ctx; | |
1157 | ||
1158 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1159 | kfree(ctx->task_ctx_data); | |
1160 | kfree(ctx); | |
1161 | } | |
1162 | ||
cdd6c482 | 1163 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1164 | { |
564c2b21 PM |
1165 | if (atomic_dec_and_test(&ctx->refcount)) { |
1166 | if (ctx->parent_ctx) | |
1167 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1168 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1169 | put_task_struct(ctx->task); |
4af57ef2 | 1170 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1171 | } |
a63eaf34 PM |
1172 | } |
1173 | ||
f63a8daa PZ |
1174 | /* |
1175 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1176 | * perf_pmu_migrate_context() we need some magic. | |
1177 | * | |
1178 | * Those places that change perf_event::ctx will hold both | |
1179 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1180 | * | |
8b10c5e2 PZ |
1181 | * Lock ordering is by mutex address. There are two other sites where |
1182 | * perf_event_context::mutex nests and those are: | |
1183 | * | |
1184 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1185 | * perf_event_exit_event() |
1186 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1187 | * |
1188 | * - perf_event_init_context() [ parent, 0 ] | |
1189 | * inherit_task_group() | |
1190 | * inherit_group() | |
1191 | * inherit_event() | |
1192 | * perf_event_alloc() | |
1193 | * perf_init_event() | |
1194 | * perf_try_init_event() [ child , 1 ] | |
1195 | * | |
1196 | * While it appears there is an obvious deadlock here -- the parent and child | |
1197 | * nesting levels are inverted between the two. This is in fact safe because | |
1198 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1199 | * spawning task cannot (yet) exit. | |
1200 | * | |
1201 | * But remember that that these are parent<->child context relations, and | |
1202 | * migration does not affect children, therefore these two orderings should not | |
1203 | * interact. | |
f63a8daa PZ |
1204 | * |
1205 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1206 | * because the sys_perf_event_open() case will install a new event and break | |
1207 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1208 | * concerned with cpuctx and that doesn't have children. | |
1209 | * | |
1210 | * The places that change perf_event::ctx will issue: | |
1211 | * | |
1212 | * perf_remove_from_context(); | |
1213 | * synchronize_rcu(); | |
1214 | * perf_install_in_context(); | |
1215 | * | |
1216 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1217 | * quiesce the event, after which we can install it in the new location. This | |
1218 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1219 | * while in transit. Therefore all such accessors should also acquire | |
1220 | * perf_event_context::mutex to serialize against this. | |
1221 | * | |
1222 | * However; because event->ctx can change while we're waiting to acquire | |
1223 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1224 | * function. | |
1225 | * | |
1226 | * Lock order: | |
79c9ce57 | 1227 | * cred_guard_mutex |
f63a8daa PZ |
1228 | * task_struct::perf_event_mutex |
1229 | * perf_event_context::mutex | |
f63a8daa | 1230 | * perf_event::child_mutex; |
07c4a776 | 1231 | * perf_event_context::lock |
f63a8daa PZ |
1232 | * perf_event::mmap_mutex |
1233 | * mmap_sem | |
82d94856 PZ |
1234 | * |
1235 | * cpu_hotplug_lock | |
1236 | * pmus_lock | |
1237 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1238 | */ |
a83fe28e PZ |
1239 | static struct perf_event_context * |
1240 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1241 | { |
1242 | struct perf_event_context *ctx; | |
1243 | ||
1244 | again: | |
1245 | rcu_read_lock(); | |
6aa7de05 | 1246 | ctx = READ_ONCE(event->ctx); |
f63a8daa PZ |
1247 | if (!atomic_inc_not_zero(&ctx->refcount)) { |
1248 | rcu_read_unlock(); | |
1249 | goto again; | |
1250 | } | |
1251 | rcu_read_unlock(); | |
1252 | ||
a83fe28e | 1253 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1254 | if (event->ctx != ctx) { |
1255 | mutex_unlock(&ctx->mutex); | |
1256 | put_ctx(ctx); | |
1257 | goto again; | |
1258 | } | |
1259 | ||
1260 | return ctx; | |
1261 | } | |
1262 | ||
a83fe28e PZ |
1263 | static inline struct perf_event_context * |
1264 | perf_event_ctx_lock(struct perf_event *event) | |
1265 | { | |
1266 | return perf_event_ctx_lock_nested(event, 0); | |
1267 | } | |
1268 | ||
f63a8daa PZ |
1269 | static void perf_event_ctx_unlock(struct perf_event *event, |
1270 | struct perf_event_context *ctx) | |
1271 | { | |
1272 | mutex_unlock(&ctx->mutex); | |
1273 | put_ctx(ctx); | |
1274 | } | |
1275 | ||
211de6eb PZ |
1276 | /* |
1277 | * This must be done under the ctx->lock, such as to serialize against | |
1278 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1279 | * calling scheduler related locks and ctx->lock nests inside those. | |
1280 | */ | |
1281 | static __must_check struct perf_event_context * | |
1282 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1283 | { |
211de6eb PZ |
1284 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1285 | ||
1286 | lockdep_assert_held(&ctx->lock); | |
1287 | ||
1288 | if (parent_ctx) | |
71a851b4 | 1289 | ctx->parent_ctx = NULL; |
5a3126d4 | 1290 | ctx->generation++; |
211de6eb PZ |
1291 | |
1292 | return parent_ctx; | |
71a851b4 PZ |
1293 | } |
1294 | ||
1d953111 ON |
1295 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1296 | enum pid_type type) | |
6844c09d | 1297 | { |
1d953111 | 1298 | u32 nr; |
6844c09d ACM |
1299 | /* |
1300 | * only top level events have the pid namespace they were created in | |
1301 | */ | |
1302 | if (event->parent) | |
1303 | event = event->parent; | |
1304 | ||
1d953111 ON |
1305 | nr = __task_pid_nr_ns(p, type, event->ns); |
1306 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1307 | if (!nr && !pid_alive(p)) | |
1308 | nr = -1; | |
1309 | return nr; | |
6844c09d ACM |
1310 | } |
1311 | ||
1d953111 | 1312 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1313 | { |
1d953111 ON |
1314 | return perf_event_pid_type(event, p, __PIDTYPE_TGID); |
1315 | } | |
6844c09d | 1316 | |
1d953111 ON |
1317 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1318 | { | |
1319 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1320 | } |
1321 | ||
7f453c24 | 1322 | /* |
cdd6c482 | 1323 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1324 | * to userspace. |
1325 | */ | |
cdd6c482 | 1326 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1327 | { |
cdd6c482 | 1328 | u64 id = event->id; |
7f453c24 | 1329 | |
cdd6c482 IM |
1330 | if (event->parent) |
1331 | id = event->parent->id; | |
7f453c24 PZ |
1332 | |
1333 | return id; | |
1334 | } | |
1335 | ||
25346b93 | 1336 | /* |
cdd6c482 | 1337 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1338 | * |
25346b93 PM |
1339 | * This has to cope with with the fact that until it is locked, |
1340 | * the context could get moved to another task. | |
1341 | */ | |
cdd6c482 | 1342 | static struct perf_event_context * |
8dc85d54 | 1343 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1344 | { |
cdd6c482 | 1345 | struct perf_event_context *ctx; |
25346b93 | 1346 | |
9ed6060d | 1347 | retry: |
058ebd0e PZ |
1348 | /* |
1349 | * One of the few rules of preemptible RCU is that one cannot do | |
1350 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1351 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1352 | * rcu_read_unlock_special(). |
1353 | * | |
1354 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1355 | * side critical section has interrupts disabled. |
058ebd0e | 1356 | */ |
2fd59077 | 1357 | local_irq_save(*flags); |
058ebd0e | 1358 | rcu_read_lock(); |
8dc85d54 | 1359 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1360 | if (ctx) { |
1361 | /* | |
1362 | * If this context is a clone of another, it might | |
1363 | * get swapped for another underneath us by | |
cdd6c482 | 1364 | * perf_event_task_sched_out, though the |
25346b93 PM |
1365 | * rcu_read_lock() protects us from any context |
1366 | * getting freed. Lock the context and check if it | |
1367 | * got swapped before we could get the lock, and retry | |
1368 | * if so. If we locked the right context, then it | |
1369 | * can't get swapped on us any more. | |
1370 | */ | |
2fd59077 | 1371 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1372 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1373 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1374 | rcu_read_unlock(); |
2fd59077 | 1375 | local_irq_restore(*flags); |
25346b93 PM |
1376 | goto retry; |
1377 | } | |
b49a9e7e | 1378 | |
63b6da39 PZ |
1379 | if (ctx->task == TASK_TOMBSTONE || |
1380 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1381 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1382 | ctx = NULL; |
828b6f0e PZ |
1383 | } else { |
1384 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1385 | } |
25346b93 PM |
1386 | } |
1387 | rcu_read_unlock(); | |
2fd59077 PM |
1388 | if (!ctx) |
1389 | local_irq_restore(*flags); | |
25346b93 PM |
1390 | return ctx; |
1391 | } | |
1392 | ||
1393 | /* | |
1394 | * Get the context for a task and increment its pin_count so it | |
1395 | * can't get swapped to another task. This also increments its | |
1396 | * reference count so that the context can't get freed. | |
1397 | */ | |
8dc85d54 PZ |
1398 | static struct perf_event_context * |
1399 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1400 | { |
cdd6c482 | 1401 | struct perf_event_context *ctx; |
25346b93 PM |
1402 | unsigned long flags; |
1403 | ||
8dc85d54 | 1404 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1405 | if (ctx) { |
1406 | ++ctx->pin_count; | |
e625cce1 | 1407 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1408 | } |
1409 | return ctx; | |
1410 | } | |
1411 | ||
cdd6c482 | 1412 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1413 | { |
1414 | unsigned long flags; | |
1415 | ||
e625cce1 | 1416 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1417 | --ctx->pin_count; |
e625cce1 | 1418 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1419 | } |
1420 | ||
f67218c3 PZ |
1421 | /* |
1422 | * Update the record of the current time in a context. | |
1423 | */ | |
1424 | static void update_context_time(struct perf_event_context *ctx) | |
1425 | { | |
1426 | u64 now = perf_clock(); | |
1427 | ||
1428 | ctx->time += now - ctx->timestamp; | |
1429 | ctx->timestamp = now; | |
1430 | } | |
1431 | ||
4158755d SE |
1432 | static u64 perf_event_time(struct perf_event *event) |
1433 | { | |
1434 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1435 | |
1436 | if (is_cgroup_event(event)) | |
1437 | return perf_cgroup_event_time(event); | |
1438 | ||
4158755d SE |
1439 | return ctx ? ctx->time : 0; |
1440 | } | |
1441 | ||
487f05e1 AS |
1442 | static enum event_type_t get_event_type(struct perf_event *event) |
1443 | { | |
1444 | struct perf_event_context *ctx = event->ctx; | |
1445 | enum event_type_t event_type; | |
1446 | ||
1447 | lockdep_assert_held(&ctx->lock); | |
1448 | ||
3bda69c1 AS |
1449 | /* |
1450 | * It's 'group type', really, because if our group leader is | |
1451 | * pinned, so are we. | |
1452 | */ | |
1453 | if (event->group_leader != event) | |
1454 | event = event->group_leader; | |
1455 | ||
487f05e1 AS |
1456 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1457 | if (!ctx->task) | |
1458 | event_type |= EVENT_CPU; | |
1459 | ||
1460 | return event_type; | |
1461 | } | |
1462 | ||
8e1a2031 | 1463 | /* |
161c85fa | 1464 | * Helper function to initialize event group nodes. |
8e1a2031 | 1465 | */ |
161c85fa | 1466 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1467 | { |
1468 | RB_CLEAR_NODE(&event->group_node); | |
1469 | event->group_index = 0; | |
1470 | } | |
1471 | ||
1472 | /* | |
1473 | * Extract pinned or flexible groups from the context | |
161c85fa | 1474 | * based on event attrs bits. |
8e1a2031 AB |
1475 | */ |
1476 | static struct perf_event_groups * | |
1477 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1478 | { |
1479 | if (event->attr.pinned) | |
1480 | return &ctx->pinned_groups; | |
1481 | else | |
1482 | return &ctx->flexible_groups; | |
1483 | } | |
1484 | ||
8e1a2031 | 1485 | /* |
161c85fa | 1486 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1487 | */ |
161c85fa | 1488 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1489 | { |
1490 | groups->tree = RB_ROOT; | |
1491 | groups->index = 0; | |
1492 | } | |
1493 | ||
1494 | /* | |
1495 | * Compare function for event groups; | |
161c85fa PZ |
1496 | * |
1497 | * Implements complex key that first sorts by CPU and then by virtual index | |
1498 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1499 | */ |
161c85fa PZ |
1500 | static bool |
1501 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1502 | { |
161c85fa PZ |
1503 | if (left->cpu < right->cpu) |
1504 | return true; | |
1505 | if (left->cpu > right->cpu) | |
1506 | return false; | |
1507 | ||
1508 | if (left->group_index < right->group_index) | |
1509 | return true; | |
1510 | if (left->group_index > right->group_index) | |
1511 | return false; | |
1512 | ||
1513 | return false; | |
8e1a2031 AB |
1514 | } |
1515 | ||
1516 | /* | |
161c85fa PZ |
1517 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1518 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1519 | * subtree. | |
8e1a2031 AB |
1520 | */ |
1521 | static void | |
1522 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1523 | struct perf_event *event) |
8e1a2031 AB |
1524 | { |
1525 | struct perf_event *node_event; | |
1526 | struct rb_node *parent; | |
1527 | struct rb_node **node; | |
1528 | ||
1529 | event->group_index = ++groups->index; | |
1530 | ||
1531 | node = &groups->tree.rb_node; | |
1532 | parent = *node; | |
1533 | ||
1534 | while (*node) { | |
1535 | parent = *node; | |
161c85fa | 1536 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1537 | |
1538 | if (perf_event_groups_less(event, node_event)) | |
1539 | node = &parent->rb_left; | |
1540 | else | |
1541 | node = &parent->rb_right; | |
1542 | } | |
1543 | ||
1544 | rb_link_node(&event->group_node, parent, node); | |
1545 | rb_insert_color(&event->group_node, &groups->tree); | |
1546 | } | |
1547 | ||
1548 | /* | |
161c85fa | 1549 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1550 | */ |
1551 | static void | |
1552 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1553 | { | |
1554 | struct perf_event_groups *groups; | |
1555 | ||
1556 | groups = get_event_groups(event, ctx); | |
1557 | perf_event_groups_insert(groups, event); | |
1558 | } | |
1559 | ||
1560 | /* | |
161c85fa | 1561 | * Delete a group from a tree. |
8e1a2031 AB |
1562 | */ |
1563 | static void | |
1564 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1565 | struct perf_event *event) |
8e1a2031 | 1566 | { |
161c85fa PZ |
1567 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1568 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1569 | |
161c85fa | 1570 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1571 | init_event_group(event); |
1572 | } | |
1573 | ||
1574 | /* | |
161c85fa | 1575 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1576 | */ |
1577 | static void | |
1578 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1579 | { | |
1580 | struct perf_event_groups *groups; | |
1581 | ||
1582 | groups = get_event_groups(event, ctx); | |
1583 | perf_event_groups_delete(groups, event); | |
1584 | } | |
1585 | ||
1586 | /* | |
161c85fa | 1587 | * Get the leftmost event in the @cpu subtree. |
8e1a2031 AB |
1588 | */ |
1589 | static struct perf_event * | |
1590 | perf_event_groups_first(struct perf_event_groups *groups, int cpu) | |
1591 | { | |
1592 | struct perf_event *node_event = NULL, *match = NULL; | |
1593 | struct rb_node *node = groups->tree.rb_node; | |
1594 | ||
1595 | while (node) { | |
161c85fa | 1596 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1597 | |
1598 | if (cpu < node_event->cpu) { | |
1599 | node = node->rb_left; | |
1600 | } else if (cpu > node_event->cpu) { | |
1601 | node = node->rb_right; | |
1602 | } else { | |
1603 | match = node_event; | |
1604 | node = node->rb_left; | |
1605 | } | |
1606 | } | |
1607 | ||
1608 | return match; | |
1609 | } | |
1610 | ||
1cac7b1a PZ |
1611 | /* |
1612 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1613 | */ | |
1614 | static struct perf_event * | |
1615 | perf_event_groups_next(struct perf_event *event) | |
1616 | { | |
1617 | struct perf_event *next; | |
1618 | ||
1619 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
1620 | if (next && next->cpu == event->cpu) | |
1621 | return next; | |
1622 | ||
1623 | return NULL; | |
1624 | } | |
1625 | ||
8e1a2031 | 1626 | /* |
161c85fa | 1627 | * Iterate through the whole groups tree. |
8e1a2031 | 1628 | */ |
6e6804d2 PZ |
1629 | #define perf_event_groups_for_each(event, groups) \ |
1630 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1631 | typeof(*event), group_node); event; \ | |
1632 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1633 | typeof(*event), group_node)) | |
8e1a2031 | 1634 | |
fccc714b | 1635 | /* |
cdd6c482 | 1636 | * Add a event from the lists for its context. |
fccc714b PZ |
1637 | * Must be called with ctx->mutex and ctx->lock held. |
1638 | */ | |
04289bb9 | 1639 | static void |
cdd6c482 | 1640 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1641 | { |
c994d613 PZ |
1642 | lockdep_assert_held(&ctx->lock); |
1643 | ||
8a49542c PZ |
1644 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1645 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1646 | |
0d3d73aa PZ |
1647 | event->tstamp = perf_event_time(event); |
1648 | ||
04289bb9 | 1649 | /* |
8a49542c PZ |
1650 | * If we're a stand alone event or group leader, we go to the context |
1651 | * list, group events are kept attached to the group so that | |
1652 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1653 | */ |
8a49542c | 1654 | if (event->group_leader == event) { |
4ff6a8de | 1655 | event->group_caps = event->event_caps; |
8e1a2031 | 1656 | add_event_to_groups(event, ctx); |
5c148194 | 1657 | } |
592903cd | 1658 | |
db4a8356 | 1659 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1660 | |
cdd6c482 IM |
1661 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1662 | ctx->nr_events++; | |
1663 | if (event->attr.inherit_stat) | |
bfbd3381 | 1664 | ctx->nr_stat++; |
5a3126d4 PZ |
1665 | |
1666 | ctx->generation++; | |
04289bb9 IM |
1667 | } |
1668 | ||
0231bb53 JO |
1669 | /* |
1670 | * Initialize event state based on the perf_event_attr::disabled. | |
1671 | */ | |
1672 | static inline void perf_event__state_init(struct perf_event *event) | |
1673 | { | |
1674 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1675 | PERF_EVENT_STATE_INACTIVE; | |
1676 | } | |
1677 | ||
a723968c | 1678 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1679 | { |
1680 | int entry = sizeof(u64); /* value */ | |
1681 | int size = 0; | |
1682 | int nr = 1; | |
1683 | ||
1684 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1685 | size += sizeof(u64); | |
1686 | ||
1687 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1688 | size += sizeof(u64); | |
1689 | ||
1690 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1691 | entry += sizeof(u64); | |
1692 | ||
1693 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1694 | nr += nr_siblings; |
c320c7b7 ACM |
1695 | size += sizeof(u64); |
1696 | } | |
1697 | ||
1698 | size += entry * nr; | |
1699 | event->read_size = size; | |
1700 | } | |
1701 | ||
a723968c | 1702 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1703 | { |
1704 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1705 | u16 size = 0; |
1706 | ||
c320c7b7 ACM |
1707 | if (sample_type & PERF_SAMPLE_IP) |
1708 | size += sizeof(data->ip); | |
1709 | ||
6844c09d ACM |
1710 | if (sample_type & PERF_SAMPLE_ADDR) |
1711 | size += sizeof(data->addr); | |
1712 | ||
1713 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1714 | size += sizeof(data->period); | |
1715 | ||
c3feedf2 AK |
1716 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1717 | size += sizeof(data->weight); | |
1718 | ||
6844c09d ACM |
1719 | if (sample_type & PERF_SAMPLE_READ) |
1720 | size += event->read_size; | |
1721 | ||
d6be9ad6 SE |
1722 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1723 | size += sizeof(data->data_src.val); | |
1724 | ||
fdfbbd07 AK |
1725 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1726 | size += sizeof(data->txn); | |
1727 | ||
fc7ce9c7 KL |
1728 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1729 | size += sizeof(data->phys_addr); | |
1730 | ||
6844c09d ACM |
1731 | event->header_size = size; |
1732 | } | |
1733 | ||
a723968c PZ |
1734 | /* |
1735 | * Called at perf_event creation and when events are attached/detached from a | |
1736 | * group. | |
1737 | */ | |
1738 | static void perf_event__header_size(struct perf_event *event) | |
1739 | { | |
1740 | __perf_event_read_size(event, | |
1741 | event->group_leader->nr_siblings); | |
1742 | __perf_event_header_size(event, event->attr.sample_type); | |
1743 | } | |
1744 | ||
6844c09d ACM |
1745 | static void perf_event__id_header_size(struct perf_event *event) |
1746 | { | |
1747 | struct perf_sample_data *data; | |
1748 | u64 sample_type = event->attr.sample_type; | |
1749 | u16 size = 0; | |
1750 | ||
c320c7b7 ACM |
1751 | if (sample_type & PERF_SAMPLE_TID) |
1752 | size += sizeof(data->tid_entry); | |
1753 | ||
1754 | if (sample_type & PERF_SAMPLE_TIME) | |
1755 | size += sizeof(data->time); | |
1756 | ||
ff3d527c AH |
1757 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1758 | size += sizeof(data->id); | |
1759 | ||
c320c7b7 ACM |
1760 | if (sample_type & PERF_SAMPLE_ID) |
1761 | size += sizeof(data->id); | |
1762 | ||
1763 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1764 | size += sizeof(data->stream_id); | |
1765 | ||
1766 | if (sample_type & PERF_SAMPLE_CPU) | |
1767 | size += sizeof(data->cpu_entry); | |
1768 | ||
6844c09d | 1769 | event->id_header_size = size; |
c320c7b7 ACM |
1770 | } |
1771 | ||
a723968c PZ |
1772 | static bool perf_event_validate_size(struct perf_event *event) |
1773 | { | |
1774 | /* | |
1775 | * The values computed here will be over-written when we actually | |
1776 | * attach the event. | |
1777 | */ | |
1778 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1779 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1780 | perf_event__id_header_size(event); | |
1781 | ||
1782 | /* | |
1783 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1784 | * Conservative limit to allow for callchains and other variable fields. | |
1785 | */ | |
1786 | if (event->read_size + event->header_size + | |
1787 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1788 | return false; | |
1789 | ||
1790 | return true; | |
1791 | } | |
1792 | ||
8a49542c PZ |
1793 | static void perf_group_attach(struct perf_event *event) |
1794 | { | |
c320c7b7 | 1795 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1796 | |
a76a82a3 PZ |
1797 | lockdep_assert_held(&event->ctx->lock); |
1798 | ||
74c3337c PZ |
1799 | /* |
1800 | * We can have double attach due to group movement in perf_event_open. | |
1801 | */ | |
1802 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1803 | return; | |
1804 | ||
8a49542c PZ |
1805 | event->attach_state |= PERF_ATTACH_GROUP; |
1806 | ||
1807 | if (group_leader == event) | |
1808 | return; | |
1809 | ||
652884fe PZ |
1810 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1811 | ||
4ff6a8de | 1812 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1813 | |
8343aae6 | 1814 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1815 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1816 | |
1817 | perf_event__header_size(group_leader); | |
1818 | ||
8343aae6 | 1819 | list_for_each_entry(pos, &group_leader->sibling_list, sibling_list) |
c320c7b7 | 1820 | perf_event__header_size(pos); |
8a49542c PZ |
1821 | } |
1822 | ||
a63eaf34 | 1823 | /* |
cdd6c482 | 1824 | * Remove a event from the lists for its context. |
fccc714b | 1825 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1826 | */ |
04289bb9 | 1827 | static void |
cdd6c482 | 1828 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1829 | { |
652884fe PZ |
1830 | WARN_ON_ONCE(event->ctx != ctx); |
1831 | lockdep_assert_held(&ctx->lock); | |
1832 | ||
8a49542c PZ |
1833 | /* |
1834 | * We can have double detach due to exit/hot-unplug + close. | |
1835 | */ | |
1836 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1837 | return; |
8a49542c PZ |
1838 | |
1839 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1840 | ||
db4a8356 | 1841 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1842 | |
cdd6c482 IM |
1843 | ctx->nr_events--; |
1844 | if (event->attr.inherit_stat) | |
bfbd3381 | 1845 | ctx->nr_stat--; |
8bc20959 | 1846 | |
cdd6c482 | 1847 | list_del_rcu(&event->event_entry); |
04289bb9 | 1848 | |
8a49542c | 1849 | if (event->group_leader == event) |
8e1a2031 | 1850 | del_event_from_groups(event, ctx); |
5c148194 | 1851 | |
b2e74a26 SE |
1852 | /* |
1853 | * If event was in error state, then keep it | |
1854 | * that way, otherwise bogus counts will be | |
1855 | * returned on read(). The only way to get out | |
1856 | * of error state is by explicit re-enabling | |
1857 | * of the event | |
1858 | */ | |
1859 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1860 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1861 | |
1862 | ctx->generation++; | |
050735b0 PZ |
1863 | } |
1864 | ||
8a49542c | 1865 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1866 | { |
1867 | struct perf_event *sibling, *tmp; | |
6668128a | 1868 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 1869 | |
6668128a | 1870 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 1871 | |
8a49542c PZ |
1872 | /* |
1873 | * We can have double detach due to exit/hot-unplug + close. | |
1874 | */ | |
1875 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1876 | return; | |
1877 | ||
1878 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1879 | ||
1880 | /* | |
1881 | * If this is a sibling, remove it from its group. | |
1882 | */ | |
1883 | if (event->group_leader != event) { | |
8343aae6 | 1884 | list_del_init(&event->sibling_list); |
8a49542c | 1885 | event->group_leader->nr_siblings--; |
c320c7b7 | 1886 | goto out; |
8a49542c PZ |
1887 | } |
1888 | ||
04289bb9 | 1889 | /* |
cdd6c482 IM |
1890 | * If this was a group event with sibling events then |
1891 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1892 | * to whatever list we are on. |
04289bb9 | 1893 | */ |
8343aae6 | 1894 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 1895 | |
04289bb9 | 1896 | sibling->group_leader = sibling; |
d6f962b5 FW |
1897 | |
1898 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1899 | sibling->group_caps = event->group_caps; |
652884fe | 1900 | |
8e1a2031 | 1901 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8343aae6 | 1902 | list_del_init(&sibling->sibling_list); |
8e1a2031 | 1903 | add_event_to_groups(sibling, event->ctx); |
6668128a PZ |
1904 | |
1905 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) { | |
1906 | struct list_head *list = sibling->attr.pinned ? | |
1907 | &ctx->pinned_active : &ctx->flexible_active; | |
1908 | ||
1909 | list_add_tail(&sibling->active_list, list); | |
1910 | } | |
8e1a2031 AB |
1911 | } |
1912 | ||
652884fe | 1913 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 1914 | } |
c320c7b7 ACM |
1915 | |
1916 | out: | |
1917 | perf_event__header_size(event->group_leader); | |
1918 | ||
8343aae6 | 1919 | list_for_each_entry(tmp, &event->group_leader->sibling_list, sibling_list) |
c320c7b7 | 1920 | perf_event__header_size(tmp); |
04289bb9 IM |
1921 | } |
1922 | ||
fadfe7be JO |
1923 | static bool is_orphaned_event(struct perf_event *event) |
1924 | { | |
a69b0ca4 | 1925 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1926 | } |
1927 | ||
2c81a647 | 1928 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1929 | { |
1930 | struct pmu *pmu = event->pmu; | |
1931 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1932 | } | |
1933 | ||
2c81a647 MR |
1934 | /* |
1935 | * Check whether we should attempt to schedule an event group based on | |
1936 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1937 | * potentially with a SW leader, so we must check all the filters, to | |
1938 | * determine whether a group is schedulable: | |
1939 | */ | |
1940 | static inline int pmu_filter_match(struct perf_event *event) | |
1941 | { | |
1942 | struct perf_event *child; | |
1943 | ||
1944 | if (!__pmu_filter_match(event)) | |
1945 | return 0; | |
1946 | ||
8343aae6 | 1947 | list_for_each_entry(child, &event->sibling_list, sibling_list) { |
2c81a647 MR |
1948 | if (!__pmu_filter_match(child)) |
1949 | return 0; | |
1950 | } | |
1951 | ||
1952 | return 1; | |
1953 | } | |
1954 | ||
fa66f07a SE |
1955 | static inline int |
1956 | event_filter_match(struct perf_event *event) | |
1957 | { | |
0b8f1e2e PZ |
1958 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1959 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1960 | } |
1961 | ||
9ffcfa6f SE |
1962 | static void |
1963 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1964 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1965 | struct perf_event_context *ctx) |
3b6f9e5c | 1966 | { |
0d3d73aa | 1967 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
1968 | |
1969 | WARN_ON_ONCE(event->ctx != ctx); | |
1970 | lockdep_assert_held(&ctx->lock); | |
1971 | ||
cdd6c482 | 1972 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1973 | return; |
3b6f9e5c | 1974 | |
6668128a PZ |
1975 | /* |
1976 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
1977 | * we can schedule events _OUT_ individually through things like | |
1978 | * __perf_remove_from_context(). | |
1979 | */ | |
1980 | list_del_init(&event->active_list); | |
1981 | ||
44377277 AS |
1982 | perf_pmu_disable(event->pmu); |
1983 | ||
28a967c3 PZ |
1984 | event->pmu->del(event, 0); |
1985 | event->oncpu = -1; | |
0d3d73aa | 1986 | |
cdd6c482 IM |
1987 | if (event->pending_disable) { |
1988 | event->pending_disable = 0; | |
0d3d73aa | 1989 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 1990 | } |
0d3d73aa | 1991 | perf_event_set_state(event, state); |
3b6f9e5c | 1992 | |
cdd6c482 | 1993 | if (!is_software_event(event)) |
3b6f9e5c | 1994 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1995 | if (!--ctx->nr_active) |
1996 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1997 | if (event->attr.freq && event->attr.sample_freq) |
1998 | ctx->nr_freq--; | |
cdd6c482 | 1999 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2000 | cpuctx->exclusive = 0; |
44377277 AS |
2001 | |
2002 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2003 | } |
2004 | ||
d859e29f | 2005 | static void |
cdd6c482 | 2006 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2007 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2008 | struct perf_event_context *ctx) |
d859e29f | 2009 | { |
cdd6c482 | 2010 | struct perf_event *event; |
0d3d73aa PZ |
2011 | |
2012 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2013 | return; | |
d859e29f | 2014 | |
3f005e7d MR |
2015 | perf_pmu_disable(ctx->pmu); |
2016 | ||
cdd6c482 | 2017 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2018 | |
2019 | /* | |
2020 | * Schedule out siblings (if any): | |
2021 | */ | |
8343aae6 | 2022 | list_for_each_entry(event, &group_event->sibling_list, sibling_list) |
cdd6c482 | 2023 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2024 | |
3f005e7d MR |
2025 | perf_pmu_enable(ctx->pmu); |
2026 | ||
0d3d73aa | 2027 | if (group_event->attr.exclusive) |
d859e29f PM |
2028 | cpuctx->exclusive = 0; |
2029 | } | |
2030 | ||
45a0e07a | 2031 | #define DETACH_GROUP 0x01UL |
0017960f | 2032 | |
0793a61d | 2033 | /* |
cdd6c482 | 2034 | * Cross CPU call to remove a performance event |
0793a61d | 2035 | * |
cdd6c482 | 2036 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2037 | * remove it from the context list. |
2038 | */ | |
fae3fde6 PZ |
2039 | static void |
2040 | __perf_remove_from_context(struct perf_event *event, | |
2041 | struct perf_cpu_context *cpuctx, | |
2042 | struct perf_event_context *ctx, | |
2043 | void *info) | |
0793a61d | 2044 | { |
45a0e07a | 2045 | unsigned long flags = (unsigned long)info; |
0793a61d | 2046 | |
3c5c8711 PZ |
2047 | if (ctx->is_active & EVENT_TIME) { |
2048 | update_context_time(ctx); | |
2049 | update_cgrp_time_from_cpuctx(cpuctx); | |
2050 | } | |
2051 | ||
cdd6c482 | 2052 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2053 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2054 | perf_group_detach(event); |
cdd6c482 | 2055 | list_del_event(event, ctx); |
39a43640 PZ |
2056 | |
2057 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2058 | ctx->is_active = 0; |
39a43640 PZ |
2059 | if (ctx->task) { |
2060 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2061 | cpuctx->task_ctx = NULL; | |
2062 | } | |
64ce3126 | 2063 | } |
0793a61d TG |
2064 | } |
2065 | ||
0793a61d | 2066 | /* |
cdd6c482 | 2067 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2068 | * |
cdd6c482 IM |
2069 | * If event->ctx is a cloned context, callers must make sure that |
2070 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2071 | * remains valid. This is OK when called from perf_release since |
2072 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2073 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2074 | * context has been detached from its task. |
0793a61d | 2075 | */ |
45a0e07a | 2076 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2077 | { |
a76a82a3 PZ |
2078 | struct perf_event_context *ctx = event->ctx; |
2079 | ||
2080 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2081 | |
45a0e07a | 2082 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2083 | |
2084 | /* | |
2085 | * The above event_function_call() can NO-OP when it hits | |
2086 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2087 | * from the context (by perf_event_exit_event()) but the grouping | |
2088 | * might still be in-tact. | |
2089 | */ | |
2090 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2091 | if ((flags & DETACH_GROUP) && | |
2092 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2093 | /* | |
2094 | * Since in that case we cannot possibly be scheduled, simply | |
2095 | * detach now. | |
2096 | */ | |
2097 | raw_spin_lock_irq(&ctx->lock); | |
2098 | perf_group_detach(event); | |
2099 | raw_spin_unlock_irq(&ctx->lock); | |
2100 | } | |
0793a61d TG |
2101 | } |
2102 | ||
d859e29f | 2103 | /* |
cdd6c482 | 2104 | * Cross CPU call to disable a performance event |
d859e29f | 2105 | */ |
fae3fde6 PZ |
2106 | static void __perf_event_disable(struct perf_event *event, |
2107 | struct perf_cpu_context *cpuctx, | |
2108 | struct perf_event_context *ctx, | |
2109 | void *info) | |
7b648018 | 2110 | { |
fae3fde6 PZ |
2111 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2112 | return; | |
7b648018 | 2113 | |
3c5c8711 PZ |
2114 | if (ctx->is_active & EVENT_TIME) { |
2115 | update_context_time(ctx); | |
2116 | update_cgrp_time_from_event(event); | |
2117 | } | |
2118 | ||
fae3fde6 PZ |
2119 | if (event == event->group_leader) |
2120 | group_sched_out(event, cpuctx, ctx); | |
2121 | else | |
2122 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2123 | |
2124 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2125 | } |
2126 | ||
d859e29f | 2127 | /* |
cdd6c482 | 2128 | * Disable a event. |
c93f7669 | 2129 | * |
cdd6c482 IM |
2130 | * If event->ctx is a cloned context, callers must make sure that |
2131 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2132 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
2133 | * perf_event_for_each_child or perf_event_for_each because they |
2134 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2135 | * goes to exit will block in perf_event_exit_event(). |
2136 | * | |
cdd6c482 | 2137 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2138 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2139 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2140 | */ |
f63a8daa | 2141 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2142 | { |
cdd6c482 | 2143 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2144 | |
e625cce1 | 2145 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2146 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2147 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2148 | return; |
53cfbf59 | 2149 | } |
e625cce1 | 2150 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2151 | |
fae3fde6 PZ |
2152 | event_function_call(event, __perf_event_disable, NULL); |
2153 | } | |
2154 | ||
2155 | void perf_event_disable_local(struct perf_event *event) | |
2156 | { | |
2157 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2158 | } |
f63a8daa PZ |
2159 | |
2160 | /* | |
2161 | * Strictly speaking kernel users cannot create groups and therefore this | |
2162 | * interface does not need the perf_event_ctx_lock() magic. | |
2163 | */ | |
2164 | void perf_event_disable(struct perf_event *event) | |
2165 | { | |
2166 | struct perf_event_context *ctx; | |
2167 | ||
2168 | ctx = perf_event_ctx_lock(event); | |
2169 | _perf_event_disable(event); | |
2170 | perf_event_ctx_unlock(event, ctx); | |
2171 | } | |
dcfce4a0 | 2172 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2173 | |
5aab90ce JO |
2174 | void perf_event_disable_inatomic(struct perf_event *event) |
2175 | { | |
2176 | event->pending_disable = 1; | |
2177 | irq_work_queue(&event->pending); | |
2178 | } | |
2179 | ||
e5d1367f | 2180 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2181 | struct perf_event_context *ctx) |
e5d1367f SE |
2182 | { |
2183 | /* | |
2184 | * use the correct time source for the time snapshot | |
2185 | * | |
2186 | * We could get by without this by leveraging the | |
2187 | * fact that to get to this function, the caller | |
2188 | * has most likely already called update_context_time() | |
2189 | * and update_cgrp_time_xx() and thus both timestamp | |
2190 | * are identical (or very close). Given that tstamp is, | |
2191 | * already adjusted for cgroup, we could say that: | |
2192 | * tstamp - ctx->timestamp | |
2193 | * is equivalent to | |
2194 | * tstamp - cgrp->timestamp. | |
2195 | * | |
2196 | * Then, in perf_output_read(), the calculation would | |
2197 | * work with no changes because: | |
2198 | * - event is guaranteed scheduled in | |
2199 | * - no scheduled out in between | |
2200 | * - thus the timestamp would be the same | |
2201 | * | |
2202 | * But this is a bit hairy. | |
2203 | * | |
2204 | * So instead, we have an explicit cgroup call to remain | |
2205 | * within the time time source all along. We believe it | |
2206 | * is cleaner and simpler to understand. | |
2207 | */ | |
2208 | if (is_cgroup_event(event)) | |
0d3d73aa | 2209 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2210 | else |
0d3d73aa | 2211 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2212 | } |
2213 | ||
4fe757dd PZ |
2214 | #define MAX_INTERRUPTS (~0ULL) |
2215 | ||
2216 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2217 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2218 | |
235c7fc7 | 2219 | static int |
9ffcfa6f | 2220 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2221 | struct perf_cpu_context *cpuctx, |
6e37738a | 2222 | struct perf_event_context *ctx) |
235c7fc7 | 2223 | { |
44377277 | 2224 | int ret = 0; |
4158755d | 2225 | |
63342411 PZ |
2226 | lockdep_assert_held(&ctx->lock); |
2227 | ||
cdd6c482 | 2228 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2229 | return 0; |
2230 | ||
95ff4ca2 AS |
2231 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2232 | /* | |
0c1cbc18 PZ |
2233 | * Order event::oncpu write to happen before the ACTIVE state is |
2234 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2235 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2236 | */ |
2237 | smp_wmb(); | |
0d3d73aa | 2238 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2239 | |
2240 | /* | |
2241 | * Unthrottle events, since we scheduled we might have missed several | |
2242 | * ticks already, also for a heavily scheduling task there is little | |
2243 | * guarantee it'll get a tick in a timely manner. | |
2244 | */ | |
2245 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2246 | perf_log_throttle(event, 1); | |
2247 | event->hw.interrupts = 0; | |
2248 | } | |
2249 | ||
44377277 AS |
2250 | perf_pmu_disable(event->pmu); |
2251 | ||
0d3d73aa | 2252 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2253 | |
ec0d7729 AS |
2254 | perf_log_itrace_start(event); |
2255 | ||
a4eaf7f1 | 2256 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2257 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2258 | event->oncpu = -1; |
44377277 AS |
2259 | ret = -EAGAIN; |
2260 | goto out; | |
235c7fc7 IM |
2261 | } |
2262 | ||
cdd6c482 | 2263 | if (!is_software_event(event)) |
3b6f9e5c | 2264 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2265 | if (!ctx->nr_active++) |
2266 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2267 | if (event->attr.freq && event->attr.sample_freq) |
2268 | ctx->nr_freq++; | |
235c7fc7 | 2269 | |
cdd6c482 | 2270 | if (event->attr.exclusive) |
3b6f9e5c PM |
2271 | cpuctx->exclusive = 1; |
2272 | ||
44377277 AS |
2273 | out: |
2274 | perf_pmu_enable(event->pmu); | |
2275 | ||
2276 | return ret; | |
235c7fc7 IM |
2277 | } |
2278 | ||
6751b71e | 2279 | static int |
cdd6c482 | 2280 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2281 | struct perf_cpu_context *cpuctx, |
6e37738a | 2282 | struct perf_event_context *ctx) |
6751b71e | 2283 | { |
6bde9b6c | 2284 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2285 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2286 | |
cdd6c482 | 2287 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2288 | return 0; |
2289 | ||
fbbe0701 | 2290 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2291 | |
9ffcfa6f | 2292 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2293 | pmu->cancel_txn(pmu); |
272325c4 | 2294 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2295 | return -EAGAIN; |
90151c35 | 2296 | } |
6751b71e PM |
2297 | |
2298 | /* | |
2299 | * Schedule in siblings as one group (if any): | |
2300 | */ | |
8343aae6 | 2301 | list_for_each_entry(event, &group_event->sibling_list, sibling_list) { |
9ffcfa6f | 2302 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2303 | partial_group = event; |
6751b71e PM |
2304 | goto group_error; |
2305 | } | |
2306 | } | |
2307 | ||
9ffcfa6f | 2308 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2309 | return 0; |
9ffcfa6f | 2310 | |
6751b71e PM |
2311 | group_error: |
2312 | /* | |
2313 | * Groups can be scheduled in as one unit only, so undo any | |
2314 | * partial group before returning: | |
0d3d73aa | 2315 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2316 | */ |
8343aae6 | 2317 | list_for_each_entry(event, &group_event->sibling_list, sibling_list) { |
cdd6c482 | 2318 | if (event == partial_group) |
0d3d73aa | 2319 | break; |
d7842da4 | 2320 | |
0d3d73aa | 2321 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2322 | } |
9ffcfa6f | 2323 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2324 | |
ad5133b7 | 2325 | pmu->cancel_txn(pmu); |
90151c35 | 2326 | |
272325c4 | 2327 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2328 | |
6751b71e PM |
2329 | return -EAGAIN; |
2330 | } | |
2331 | ||
3b6f9e5c | 2332 | /* |
cdd6c482 | 2333 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2334 | */ |
cdd6c482 | 2335 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2336 | struct perf_cpu_context *cpuctx, |
2337 | int can_add_hw) | |
2338 | { | |
2339 | /* | |
cdd6c482 | 2340 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2341 | */ |
4ff6a8de | 2342 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2343 | return 1; |
2344 | /* | |
2345 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2346 | * events can go on. |
3b6f9e5c PM |
2347 | */ |
2348 | if (cpuctx->exclusive) | |
2349 | return 0; | |
2350 | /* | |
2351 | * If this group is exclusive and there are already | |
cdd6c482 | 2352 | * events on the CPU, it can't go on. |
3b6f9e5c | 2353 | */ |
cdd6c482 | 2354 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2355 | return 0; |
2356 | /* | |
2357 | * Otherwise, try to add it if all previous groups were able | |
2358 | * to go on. | |
2359 | */ | |
2360 | return can_add_hw; | |
2361 | } | |
2362 | ||
cdd6c482 IM |
2363 | static void add_event_to_ctx(struct perf_event *event, |
2364 | struct perf_event_context *ctx) | |
53cfbf59 | 2365 | { |
cdd6c482 | 2366 | list_add_event(event, ctx); |
8a49542c | 2367 | perf_group_attach(event); |
53cfbf59 PM |
2368 | } |
2369 | ||
bd2afa49 PZ |
2370 | static void ctx_sched_out(struct perf_event_context *ctx, |
2371 | struct perf_cpu_context *cpuctx, | |
2372 | enum event_type_t event_type); | |
2c29ef0f PZ |
2373 | static void |
2374 | ctx_sched_in(struct perf_event_context *ctx, | |
2375 | struct perf_cpu_context *cpuctx, | |
2376 | enum event_type_t event_type, | |
2377 | struct task_struct *task); | |
fe4b04fa | 2378 | |
bd2afa49 | 2379 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2380 | struct perf_event_context *ctx, |
2381 | enum event_type_t event_type) | |
bd2afa49 PZ |
2382 | { |
2383 | if (!cpuctx->task_ctx) | |
2384 | return; | |
2385 | ||
2386 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2387 | return; | |
2388 | ||
487f05e1 | 2389 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2390 | } |
2391 | ||
dce5855b PZ |
2392 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2393 | struct perf_event_context *ctx, | |
2394 | struct task_struct *task) | |
2395 | { | |
2396 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2397 | if (ctx) | |
2398 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2399 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2400 | if (ctx) | |
2401 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2402 | } | |
2403 | ||
487f05e1 AS |
2404 | /* |
2405 | * We want to maintain the following priority of scheduling: | |
2406 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2407 | * - task pinned (EVENT_PINNED) | |
2408 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2409 | * - task flexible (EVENT_FLEXIBLE). | |
2410 | * | |
2411 | * In order to avoid unscheduling and scheduling back in everything every | |
2412 | * time an event is added, only do it for the groups of equal priority and | |
2413 | * below. | |
2414 | * | |
2415 | * This can be called after a batch operation on task events, in which case | |
2416 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2417 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2418 | */ | |
3e349507 | 2419 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2420 | struct perf_event_context *task_ctx, |
2421 | enum event_type_t event_type) | |
0017960f | 2422 | { |
487f05e1 AS |
2423 | enum event_type_t ctx_event_type = event_type & EVENT_ALL; |
2424 | bool cpu_event = !!(event_type & EVENT_CPU); | |
2425 | ||
2426 | /* | |
2427 | * If pinned groups are involved, flexible groups also need to be | |
2428 | * scheduled out. | |
2429 | */ | |
2430 | if (event_type & EVENT_PINNED) | |
2431 | event_type |= EVENT_FLEXIBLE; | |
2432 | ||
3e349507 PZ |
2433 | perf_pmu_disable(cpuctx->ctx.pmu); |
2434 | if (task_ctx) | |
487f05e1 AS |
2435 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2436 | ||
2437 | /* | |
2438 | * Decide which cpu ctx groups to schedule out based on the types | |
2439 | * of events that caused rescheduling: | |
2440 | * - EVENT_CPU: schedule out corresponding groups; | |
2441 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2442 | * - otherwise, do nothing more. | |
2443 | */ | |
2444 | if (cpu_event) | |
2445 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2446 | else if (ctx_event_type & EVENT_PINNED) | |
2447 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2448 | ||
3e349507 PZ |
2449 | perf_event_sched_in(cpuctx, task_ctx, current); |
2450 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2451 | } |
2452 | ||
0793a61d | 2453 | /* |
cdd6c482 | 2454 | * Cross CPU call to install and enable a performance event |
682076ae | 2455 | * |
a096309b PZ |
2456 | * Very similar to remote_function() + event_function() but cannot assume that |
2457 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2458 | */ |
fe4b04fa | 2459 | static int __perf_install_in_context(void *info) |
0793a61d | 2460 | { |
a096309b PZ |
2461 | struct perf_event *event = info; |
2462 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2463 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2464 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2465 | bool reprogram = true; |
a096309b | 2466 | int ret = 0; |
0793a61d | 2467 | |
63b6da39 | 2468 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2469 | if (ctx->task) { |
b58f6b0d PZ |
2470 | raw_spin_lock(&ctx->lock); |
2471 | task_ctx = ctx; | |
a096309b | 2472 | |
63cae12b | 2473 | reprogram = (ctx->task == current); |
b58f6b0d | 2474 | |
39a43640 | 2475 | /* |
63cae12b PZ |
2476 | * If the task is running, it must be running on this CPU, |
2477 | * otherwise we cannot reprogram things. | |
2478 | * | |
2479 | * If its not running, we don't care, ctx->lock will | |
2480 | * serialize against it becoming runnable. | |
39a43640 | 2481 | */ |
63cae12b PZ |
2482 | if (task_curr(ctx->task) && !reprogram) { |
2483 | ret = -ESRCH; | |
2484 | goto unlock; | |
2485 | } | |
a096309b | 2486 | |
63cae12b | 2487 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2488 | } else if (task_ctx) { |
2489 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2490 | } |
b58f6b0d | 2491 | |
63cae12b | 2492 | if (reprogram) { |
a096309b PZ |
2493 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2494 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2495 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2496 | } else { |
2497 | add_event_to_ctx(event, ctx); | |
2498 | } | |
2499 | ||
63b6da39 | 2500 | unlock: |
2c29ef0f | 2501 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2502 | |
a096309b | 2503 | return ret; |
0793a61d TG |
2504 | } |
2505 | ||
2506 | /* | |
a096309b PZ |
2507 | * Attach a performance event to a context. |
2508 | * | |
2509 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2510 | */ |
2511 | static void | |
cdd6c482 IM |
2512 | perf_install_in_context(struct perf_event_context *ctx, |
2513 | struct perf_event *event, | |
0793a61d TG |
2514 | int cpu) |
2515 | { | |
a096309b | 2516 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2517 | |
fe4b04fa PZ |
2518 | lockdep_assert_held(&ctx->mutex); |
2519 | ||
0cda4c02 YZ |
2520 | if (event->cpu != -1) |
2521 | event->cpu = cpu; | |
c3f00c70 | 2522 | |
0b8f1e2e PZ |
2523 | /* |
2524 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2525 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2526 | */ | |
2527 | smp_store_release(&event->ctx, ctx); | |
2528 | ||
a096309b PZ |
2529 | if (!task) { |
2530 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2531 | return; | |
2532 | } | |
2533 | ||
2534 | /* | |
2535 | * Should not happen, we validate the ctx is still alive before calling. | |
2536 | */ | |
2537 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2538 | return; | |
2539 | ||
39a43640 PZ |
2540 | /* |
2541 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2542 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2543 | * |
2544 | * Instead we use task_curr(), which tells us if the task is running. | |
2545 | * However, since we use task_curr() outside of rq::lock, we can race | |
2546 | * against the actual state. This means the result can be wrong. | |
2547 | * | |
2548 | * If we get a false positive, we retry, this is harmless. | |
2549 | * | |
2550 | * If we get a false negative, things are complicated. If we are after | |
2551 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2552 | * value must be correct. If we're before, it doesn't matter since | |
2553 | * perf_event_context_sched_in() will program the counter. | |
2554 | * | |
2555 | * However, this hinges on the remote context switch having observed | |
2556 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2557 | * ctx::lock in perf_event_context_sched_in(). | |
2558 | * | |
2559 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2560 | * we know any future context switch of task must see the | |
2561 | * perf_event_ctpx[] store. | |
39a43640 | 2562 | */ |
63cae12b | 2563 | |
63b6da39 | 2564 | /* |
63cae12b PZ |
2565 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2566 | * task_cpu() load, such that if the IPI then does not find the task | |
2567 | * running, a future context switch of that task must observe the | |
2568 | * store. | |
63b6da39 | 2569 | */ |
63cae12b PZ |
2570 | smp_mb(); |
2571 | again: | |
2572 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2573 | return; |
2574 | ||
2575 | raw_spin_lock_irq(&ctx->lock); | |
2576 | task = ctx->task; | |
84c4e620 | 2577 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2578 | /* |
2579 | * Cannot happen because we already checked above (which also | |
2580 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2581 | * against perf_event_exit_task_context(). | |
2582 | */ | |
63b6da39 PZ |
2583 | raw_spin_unlock_irq(&ctx->lock); |
2584 | return; | |
2585 | } | |
39a43640 | 2586 | /* |
63cae12b PZ |
2587 | * If the task is not running, ctx->lock will avoid it becoming so, |
2588 | * thus we can safely install the event. | |
39a43640 | 2589 | */ |
63cae12b PZ |
2590 | if (task_curr(task)) { |
2591 | raw_spin_unlock_irq(&ctx->lock); | |
2592 | goto again; | |
2593 | } | |
2594 | add_event_to_ctx(event, ctx); | |
2595 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2596 | } |
2597 | ||
d859e29f | 2598 | /* |
cdd6c482 | 2599 | * Cross CPU call to enable a performance event |
d859e29f | 2600 | */ |
fae3fde6 PZ |
2601 | static void __perf_event_enable(struct perf_event *event, |
2602 | struct perf_cpu_context *cpuctx, | |
2603 | struct perf_event_context *ctx, | |
2604 | void *info) | |
04289bb9 | 2605 | { |
cdd6c482 | 2606 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2607 | struct perf_event_context *task_ctx; |
04289bb9 | 2608 | |
6e801e01 PZ |
2609 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2610 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2611 | return; |
3cbed429 | 2612 | |
bd2afa49 PZ |
2613 | if (ctx->is_active) |
2614 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2615 | ||
0d3d73aa | 2616 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2617 | |
fae3fde6 PZ |
2618 | if (!ctx->is_active) |
2619 | return; | |
2620 | ||
e5d1367f | 2621 | if (!event_filter_match(event)) { |
bd2afa49 | 2622 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2623 | return; |
e5d1367f | 2624 | } |
f4c4176f | 2625 | |
04289bb9 | 2626 | /* |
cdd6c482 | 2627 | * If the event is in a group and isn't the group leader, |
d859e29f | 2628 | * then don't put it on unless the group is on. |
04289bb9 | 2629 | */ |
bd2afa49 PZ |
2630 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2631 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2632 | return; |
bd2afa49 | 2633 | } |
fe4b04fa | 2634 | |
fae3fde6 PZ |
2635 | task_ctx = cpuctx->task_ctx; |
2636 | if (ctx->task) | |
2637 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2638 | |
487f05e1 | 2639 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2640 | } |
2641 | ||
d859e29f | 2642 | /* |
cdd6c482 | 2643 | * Enable a event. |
c93f7669 | 2644 | * |
cdd6c482 IM |
2645 | * If event->ctx is a cloned context, callers must make sure that |
2646 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2647 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2648 | * perf_event_for_each_child or perf_event_for_each as described |
2649 | * for perf_event_disable. | |
d859e29f | 2650 | */ |
f63a8daa | 2651 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2652 | { |
cdd6c482 | 2653 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2654 | |
7b648018 | 2655 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2656 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2657 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2658 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2659 | return; |
2660 | } | |
2661 | ||
d859e29f | 2662 | /* |
cdd6c482 | 2663 | * If the event is in error state, clear that first. |
7b648018 PZ |
2664 | * |
2665 | * That way, if we see the event in error state below, we know that it | |
2666 | * has gone back into error state, as distinct from the task having | |
2667 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2668 | */ |
cdd6c482 IM |
2669 | if (event->state == PERF_EVENT_STATE_ERROR) |
2670 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2671 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2672 | |
fae3fde6 | 2673 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2674 | } |
f63a8daa PZ |
2675 | |
2676 | /* | |
2677 | * See perf_event_disable(); | |
2678 | */ | |
2679 | void perf_event_enable(struct perf_event *event) | |
2680 | { | |
2681 | struct perf_event_context *ctx; | |
2682 | ||
2683 | ctx = perf_event_ctx_lock(event); | |
2684 | _perf_event_enable(event); | |
2685 | perf_event_ctx_unlock(event, ctx); | |
2686 | } | |
dcfce4a0 | 2687 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2688 | |
375637bc AS |
2689 | struct stop_event_data { |
2690 | struct perf_event *event; | |
2691 | unsigned int restart; | |
2692 | }; | |
2693 | ||
95ff4ca2 AS |
2694 | static int __perf_event_stop(void *info) |
2695 | { | |
375637bc AS |
2696 | struct stop_event_data *sd = info; |
2697 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2698 | |
375637bc | 2699 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2700 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2701 | return 0; | |
2702 | ||
2703 | /* matches smp_wmb() in event_sched_in() */ | |
2704 | smp_rmb(); | |
2705 | ||
2706 | /* | |
2707 | * There is a window with interrupts enabled before we get here, | |
2708 | * so we need to check again lest we try to stop another CPU's event. | |
2709 | */ | |
2710 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2711 | return -EAGAIN; | |
2712 | ||
2713 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2714 | ||
375637bc AS |
2715 | /* |
2716 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2717 | * but it is only used for events with AUX ring buffer, and such | |
2718 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2719 | * see comments in perf_aux_output_begin(). | |
2720 | * | |
2721 | * Since this is happening on a event-local CPU, no trace is lost | |
2722 | * while restarting. | |
2723 | */ | |
2724 | if (sd->restart) | |
c9bbdd48 | 2725 | event->pmu->start(event, 0); |
375637bc | 2726 | |
95ff4ca2 AS |
2727 | return 0; |
2728 | } | |
2729 | ||
767ae086 | 2730 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2731 | { |
2732 | struct stop_event_data sd = { | |
2733 | .event = event, | |
767ae086 | 2734 | .restart = restart, |
375637bc AS |
2735 | }; |
2736 | int ret = 0; | |
2737 | ||
2738 | do { | |
2739 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2740 | return 0; | |
2741 | ||
2742 | /* matches smp_wmb() in event_sched_in() */ | |
2743 | smp_rmb(); | |
2744 | ||
2745 | /* | |
2746 | * We only want to restart ACTIVE events, so if the event goes | |
2747 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2748 | * fall through with ret==-ENXIO. | |
2749 | */ | |
2750 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2751 | __perf_event_stop, &sd); | |
2752 | } while (ret == -EAGAIN); | |
2753 | ||
2754 | return ret; | |
2755 | } | |
2756 | ||
2757 | /* | |
2758 | * In order to contain the amount of racy and tricky in the address filter | |
2759 | * configuration management, it is a two part process: | |
2760 | * | |
2761 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2762 | * we update the addresses of corresponding vmas in | |
2763 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2764 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2765 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2766 | * if the generation has changed since the previous call. | |
2767 | * | |
2768 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2769 | * | |
2770 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2771 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2772 | * ioctl; | |
2773 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2774 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2775 | * for reading; | |
2776 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2777 | * of exec. | |
2778 | */ | |
2779 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2780 | { | |
2781 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2782 | ||
2783 | if (!has_addr_filter(event)) | |
2784 | return; | |
2785 | ||
2786 | raw_spin_lock(&ifh->lock); | |
2787 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2788 | event->pmu->addr_filters_sync(event); | |
2789 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2790 | } | |
2791 | raw_spin_unlock(&ifh->lock); | |
2792 | } | |
2793 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2794 | ||
f63a8daa | 2795 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2796 | { |
2023b359 | 2797 | /* |
cdd6c482 | 2798 | * not supported on inherited events |
2023b359 | 2799 | */ |
2e939d1d | 2800 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2801 | return -EINVAL; |
2802 | ||
cdd6c482 | 2803 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2804 | _perf_event_enable(event); |
2023b359 PZ |
2805 | |
2806 | return 0; | |
79f14641 | 2807 | } |
f63a8daa PZ |
2808 | |
2809 | /* | |
2810 | * See perf_event_disable() | |
2811 | */ | |
2812 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2813 | { | |
2814 | struct perf_event_context *ctx; | |
2815 | int ret; | |
2816 | ||
2817 | ctx = perf_event_ctx_lock(event); | |
2818 | ret = _perf_event_refresh(event, refresh); | |
2819 | perf_event_ctx_unlock(event, ctx); | |
2820 | ||
2821 | return ret; | |
2822 | } | |
26ca5c11 | 2823 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2824 | |
5b0311e1 FW |
2825 | static void ctx_sched_out(struct perf_event_context *ctx, |
2826 | struct perf_cpu_context *cpuctx, | |
2827 | enum event_type_t event_type) | |
235c7fc7 | 2828 | { |
6668128a | 2829 | struct perf_event *event, *tmp; |
db24d33e | 2830 | int is_active = ctx->is_active; |
235c7fc7 | 2831 | |
c994d613 | 2832 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2833 | |
39a43640 PZ |
2834 | if (likely(!ctx->nr_events)) { |
2835 | /* | |
2836 | * See __perf_remove_from_context(). | |
2837 | */ | |
2838 | WARN_ON_ONCE(ctx->is_active); | |
2839 | if (ctx->task) | |
2840 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2841 | return; |
39a43640 PZ |
2842 | } |
2843 | ||
db24d33e | 2844 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2845 | if (!(ctx->is_active & EVENT_ALL)) |
2846 | ctx->is_active = 0; | |
2847 | ||
63e30d3e PZ |
2848 | if (ctx->task) { |
2849 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2850 | if (!ctx->is_active) | |
2851 | cpuctx->task_ctx = NULL; | |
2852 | } | |
facc4307 | 2853 | |
8fdc6539 PZ |
2854 | /* |
2855 | * Always update time if it was set; not only when it changes. | |
2856 | * Otherwise we can 'forget' to update time for any but the last | |
2857 | * context we sched out. For example: | |
2858 | * | |
2859 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2860 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2861 | * | |
2862 | * would only update time for the pinned events. | |
2863 | */ | |
3cbaa590 PZ |
2864 | if (is_active & EVENT_TIME) { |
2865 | /* update (and stop) ctx time */ | |
2866 | update_context_time(ctx); | |
2867 | update_cgrp_time_from_cpuctx(cpuctx); | |
2868 | } | |
2869 | ||
8fdc6539 PZ |
2870 | is_active ^= ctx->is_active; /* changed bits */ |
2871 | ||
3cbaa590 | 2872 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2873 | return; |
5b0311e1 | 2874 | |
075e0b00 | 2875 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2876 | if (is_active & EVENT_PINNED) { |
6668128a | 2877 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 2878 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2879 | } |
889ff015 | 2880 | |
3cbaa590 | 2881 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 2882 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 2883 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2884 | } |
1b9a644f | 2885 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2886 | } |
2887 | ||
564c2b21 | 2888 | /* |
5a3126d4 PZ |
2889 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2890 | * cloned from the same version of the same context. | |
2891 | * | |
2892 | * Equivalence is measured using a generation number in the context that is | |
2893 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2894 | * and list_del_event(). | |
564c2b21 | 2895 | */ |
cdd6c482 IM |
2896 | static int context_equiv(struct perf_event_context *ctx1, |
2897 | struct perf_event_context *ctx2) | |
564c2b21 | 2898 | { |
211de6eb PZ |
2899 | lockdep_assert_held(&ctx1->lock); |
2900 | lockdep_assert_held(&ctx2->lock); | |
2901 | ||
5a3126d4 PZ |
2902 | /* Pinning disables the swap optimization */ |
2903 | if (ctx1->pin_count || ctx2->pin_count) | |
2904 | return 0; | |
2905 | ||
2906 | /* If ctx1 is the parent of ctx2 */ | |
2907 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2908 | return 1; | |
2909 | ||
2910 | /* If ctx2 is the parent of ctx1 */ | |
2911 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2912 | return 1; | |
2913 | ||
2914 | /* | |
2915 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2916 | * hierarchy, see perf_event_init_context(). | |
2917 | */ | |
2918 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2919 | ctx1->parent_gen == ctx2->parent_gen) | |
2920 | return 1; | |
2921 | ||
2922 | /* Unmatched */ | |
2923 | return 0; | |
564c2b21 PM |
2924 | } |
2925 | ||
cdd6c482 IM |
2926 | static void __perf_event_sync_stat(struct perf_event *event, |
2927 | struct perf_event *next_event) | |
bfbd3381 PZ |
2928 | { |
2929 | u64 value; | |
2930 | ||
cdd6c482 | 2931 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2932 | return; |
2933 | ||
2934 | /* | |
cdd6c482 | 2935 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2936 | * because we're in the middle of a context switch and have IRQs |
2937 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2938 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2939 | * don't need to use it. |
2940 | */ | |
0d3d73aa | 2941 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 2942 | event->pmu->read(event); |
bfbd3381 | 2943 | |
0d3d73aa | 2944 | perf_event_update_time(event); |
bfbd3381 PZ |
2945 | |
2946 | /* | |
cdd6c482 | 2947 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2948 | * values when we flip the contexts. |
2949 | */ | |
e7850595 PZ |
2950 | value = local64_read(&next_event->count); |
2951 | value = local64_xchg(&event->count, value); | |
2952 | local64_set(&next_event->count, value); | |
bfbd3381 | 2953 | |
cdd6c482 IM |
2954 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2955 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2956 | |
bfbd3381 | 2957 | /* |
19d2e755 | 2958 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2959 | */ |
cdd6c482 IM |
2960 | perf_event_update_userpage(event); |
2961 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2962 | } |
2963 | ||
cdd6c482 IM |
2964 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2965 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2966 | { |
cdd6c482 | 2967 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2968 | |
2969 | if (!ctx->nr_stat) | |
2970 | return; | |
2971 | ||
02ffdbc8 PZ |
2972 | update_context_time(ctx); |
2973 | ||
cdd6c482 IM |
2974 | event = list_first_entry(&ctx->event_list, |
2975 | struct perf_event, event_entry); | |
bfbd3381 | 2976 | |
cdd6c482 IM |
2977 | next_event = list_first_entry(&next_ctx->event_list, |
2978 | struct perf_event, event_entry); | |
bfbd3381 | 2979 | |
cdd6c482 IM |
2980 | while (&event->event_entry != &ctx->event_list && |
2981 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2982 | |
cdd6c482 | 2983 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2984 | |
cdd6c482 IM |
2985 | event = list_next_entry(event, event_entry); |
2986 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2987 | } |
2988 | } | |
2989 | ||
fe4b04fa PZ |
2990 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2991 | struct task_struct *next) | |
0793a61d | 2992 | { |
8dc85d54 | 2993 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2994 | struct perf_event_context *next_ctx; |
5a3126d4 | 2995 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2996 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2997 | int do_switch = 1; |
0793a61d | 2998 | |
108b02cf PZ |
2999 | if (likely(!ctx)) |
3000 | return; | |
10989fb2 | 3001 | |
108b02cf PZ |
3002 | cpuctx = __get_cpu_context(ctx); |
3003 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3004 | return; |
3005 | ||
c93f7669 | 3006 | rcu_read_lock(); |
8dc85d54 | 3007 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3008 | if (!next_ctx) |
3009 | goto unlock; | |
3010 | ||
3011 | parent = rcu_dereference(ctx->parent_ctx); | |
3012 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3013 | ||
3014 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3015 | if (!parent && !next_parent) |
5a3126d4 PZ |
3016 | goto unlock; |
3017 | ||
3018 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3019 | /* |
3020 | * Looks like the two contexts are clones, so we might be | |
3021 | * able to optimize the context switch. We lock both | |
3022 | * contexts and check that they are clones under the | |
3023 | * lock (including re-checking that neither has been | |
3024 | * uncloned in the meantime). It doesn't matter which | |
3025 | * order we take the locks because no other cpu could | |
3026 | * be trying to lock both of these tasks. | |
3027 | */ | |
e625cce1 TG |
3028 | raw_spin_lock(&ctx->lock); |
3029 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3030 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
3031 | WRITE_ONCE(ctx->task, next); |
3032 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
3033 | |
3034 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
3035 | ||
63b6da39 PZ |
3036 | /* |
3037 | * RCU_INIT_POINTER here is safe because we've not | |
3038 | * modified the ctx and the above modification of | |
3039 | * ctx->task and ctx->task_ctx_data are immaterial | |
3040 | * since those values are always verified under | |
3041 | * ctx->lock which we're now holding. | |
3042 | */ | |
3043 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3044 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3045 | ||
c93f7669 | 3046 | do_switch = 0; |
bfbd3381 | 3047 | |
cdd6c482 | 3048 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3049 | } |
e625cce1 TG |
3050 | raw_spin_unlock(&next_ctx->lock); |
3051 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3052 | } |
5a3126d4 | 3053 | unlock: |
c93f7669 | 3054 | rcu_read_unlock(); |
564c2b21 | 3055 | |
c93f7669 | 3056 | if (do_switch) { |
facc4307 | 3057 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3058 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3059 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3060 | } |
0793a61d TG |
3061 | } |
3062 | ||
e48c1788 PZ |
3063 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3064 | ||
ba532500 YZ |
3065 | void perf_sched_cb_dec(struct pmu *pmu) |
3066 | { | |
e48c1788 PZ |
3067 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3068 | ||
ba532500 | 3069 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3070 | |
3071 | if (!--cpuctx->sched_cb_usage) | |
3072 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3073 | } |
3074 | ||
e48c1788 | 3075 | |
ba532500 YZ |
3076 | void perf_sched_cb_inc(struct pmu *pmu) |
3077 | { | |
e48c1788 PZ |
3078 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3079 | ||
3080 | if (!cpuctx->sched_cb_usage++) | |
3081 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3082 | ||
ba532500 YZ |
3083 | this_cpu_inc(perf_sched_cb_usages); |
3084 | } | |
3085 | ||
3086 | /* | |
3087 | * This function provides the context switch callback to the lower code | |
3088 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3089 | * |
3090 | * This callback is relevant even to per-cpu events; for example multi event | |
3091 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3092 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3093 | */ |
3094 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3095 | struct task_struct *next, | |
3096 | bool sched_in) | |
3097 | { | |
3098 | struct perf_cpu_context *cpuctx; | |
3099 | struct pmu *pmu; | |
ba532500 YZ |
3100 | |
3101 | if (prev == next) | |
3102 | return; | |
3103 | ||
e48c1788 | 3104 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3105 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3106 | |
e48c1788 PZ |
3107 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3108 | continue; | |
ba532500 | 3109 | |
e48c1788 PZ |
3110 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3111 | perf_pmu_disable(pmu); | |
ba532500 | 3112 | |
e48c1788 | 3113 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3114 | |
e48c1788 PZ |
3115 | perf_pmu_enable(pmu); |
3116 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3117 | } |
ba532500 YZ |
3118 | } |
3119 | ||
45ac1403 AH |
3120 | static void perf_event_switch(struct task_struct *task, |
3121 | struct task_struct *next_prev, bool sched_in); | |
3122 | ||
8dc85d54 PZ |
3123 | #define for_each_task_context_nr(ctxn) \ |
3124 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3125 | ||
3126 | /* | |
3127 | * Called from scheduler to remove the events of the current task, | |
3128 | * with interrupts disabled. | |
3129 | * | |
3130 | * We stop each event and update the event value in event->count. | |
3131 | * | |
3132 | * This does not protect us against NMI, but disable() | |
3133 | * sets the disabled bit in the control field of event _before_ | |
3134 | * accessing the event control register. If a NMI hits, then it will | |
3135 | * not restart the event. | |
3136 | */ | |
ab0cce56 JO |
3137 | void __perf_event_task_sched_out(struct task_struct *task, |
3138 | struct task_struct *next) | |
8dc85d54 PZ |
3139 | { |
3140 | int ctxn; | |
3141 | ||
ba532500 YZ |
3142 | if (__this_cpu_read(perf_sched_cb_usages)) |
3143 | perf_pmu_sched_task(task, next, false); | |
3144 | ||
45ac1403 AH |
3145 | if (atomic_read(&nr_switch_events)) |
3146 | perf_event_switch(task, next, false); | |
3147 | ||
8dc85d54 PZ |
3148 | for_each_task_context_nr(ctxn) |
3149 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3150 | |
3151 | /* | |
3152 | * if cgroup events exist on this CPU, then we need | |
3153 | * to check if we have to switch out PMU state. | |
3154 | * cgroup event are system-wide mode only | |
3155 | */ | |
4a32fea9 | 3156 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3157 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3158 | } |
3159 | ||
5b0311e1 FW |
3160 | /* |
3161 | * Called with IRQs disabled | |
3162 | */ | |
3163 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3164 | enum event_type_t event_type) | |
3165 | { | |
3166 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3167 | } |
3168 | ||
1cac7b1a PZ |
3169 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3170 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3171 | { |
1cac7b1a PZ |
3172 | struct perf_event **evt, *evt1, *evt2; |
3173 | int ret; | |
8e1a2031 | 3174 | |
1cac7b1a PZ |
3175 | evt1 = perf_event_groups_first(groups, -1); |
3176 | evt2 = perf_event_groups_first(groups, cpu); | |
3177 | ||
3178 | while (evt1 || evt2) { | |
3179 | if (evt1 && evt2) { | |
3180 | if (evt1->group_index < evt2->group_index) | |
3181 | evt = &evt1; | |
3182 | else | |
3183 | evt = &evt2; | |
3184 | } else if (evt1) { | |
3185 | evt = &evt1; | |
3186 | } else { | |
3187 | evt = &evt2; | |
8e1a2031 | 3188 | } |
1cac7b1a PZ |
3189 | |
3190 | ret = func(*evt, data); | |
3191 | if (ret) | |
3192 | return ret; | |
3193 | ||
3194 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3195 | } |
0793a61d | 3196 | |
1cac7b1a PZ |
3197 | return 0; |
3198 | } | |
3199 | ||
3200 | struct sched_in_data { | |
3201 | struct perf_event_context *ctx; | |
3202 | struct perf_cpu_context *cpuctx; | |
3203 | int can_add_hw; | |
3204 | }; | |
3205 | ||
3206 | static int pinned_sched_in(struct perf_event *event, void *data) | |
3207 | { | |
3208 | struct sched_in_data *sid = data; | |
3209 | ||
3210 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3211 | return 0; | |
3212 | ||
3213 | if (!event_filter_match(event)) | |
3214 | return 0; | |
3215 | ||
6668128a PZ |
3216 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3217 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
3218 | list_add_tail(&event->active_list, &sid->ctx->pinned_active); | |
3219 | } | |
1cac7b1a PZ |
3220 | |
3221 | /* | |
3222 | * If this pinned group hasn't been scheduled, | |
3223 | * put it in error state. | |
3224 | */ | |
3225 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
3226 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3227 | ||
3228 | return 0; | |
3229 | } | |
3230 | ||
3231 | static int flexible_sched_in(struct perf_event *event, void *data) | |
3232 | { | |
3233 | struct sched_in_data *sid = data; | |
3234 | ||
3235 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3236 | return 0; | |
3237 | ||
3238 | if (!event_filter_match(event)) | |
3239 | return 0; | |
3240 | ||
3241 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { | |
6668128a PZ |
3242 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) |
3243 | list_add_tail(&event->active_list, &sid->ctx->flexible_active); | |
3244 | else | |
1cac7b1a | 3245 | sid->can_add_hw = 0; |
3b6f9e5c | 3246 | } |
1cac7b1a PZ |
3247 | |
3248 | return 0; | |
5b0311e1 FW |
3249 | } |
3250 | ||
3251 | static void | |
1cac7b1a PZ |
3252 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3253 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3254 | { |
1cac7b1a PZ |
3255 | struct sched_in_data sid = { |
3256 | .ctx = ctx, | |
3257 | .cpuctx = cpuctx, | |
3258 | .can_add_hw = 1, | |
3259 | }; | |
3b6f9e5c | 3260 | |
1cac7b1a PZ |
3261 | visit_groups_merge(&ctx->pinned_groups, |
3262 | smp_processor_id(), | |
3263 | pinned_sched_in, &sid); | |
3264 | } | |
8e1a2031 | 3265 | |
1cac7b1a PZ |
3266 | static void |
3267 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3268 | struct perf_cpu_context *cpuctx) | |
3269 | { | |
3270 | struct sched_in_data sid = { | |
3271 | .ctx = ctx, | |
3272 | .cpuctx = cpuctx, | |
3273 | .can_add_hw = 1, | |
3274 | }; | |
0793a61d | 3275 | |
1cac7b1a PZ |
3276 | visit_groups_merge(&ctx->flexible_groups, |
3277 | smp_processor_id(), | |
3278 | flexible_sched_in, &sid); | |
5b0311e1 FW |
3279 | } |
3280 | ||
3281 | static void | |
3282 | ctx_sched_in(struct perf_event_context *ctx, | |
3283 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3284 | enum event_type_t event_type, |
3285 | struct task_struct *task) | |
5b0311e1 | 3286 | { |
db24d33e | 3287 | int is_active = ctx->is_active; |
c994d613 PZ |
3288 | u64 now; |
3289 | ||
3290 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3291 | |
5b0311e1 | 3292 | if (likely(!ctx->nr_events)) |
facc4307 | 3293 | return; |
5b0311e1 | 3294 | |
3cbaa590 | 3295 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3296 | if (ctx->task) { |
3297 | if (!is_active) | |
3298 | cpuctx->task_ctx = ctx; | |
3299 | else | |
3300 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3301 | } | |
3302 | ||
3cbaa590 PZ |
3303 | is_active ^= ctx->is_active; /* changed bits */ |
3304 | ||
3305 | if (is_active & EVENT_TIME) { | |
3306 | /* start ctx time */ | |
3307 | now = perf_clock(); | |
3308 | ctx->timestamp = now; | |
3309 | perf_cgroup_set_timestamp(task, ctx); | |
3310 | } | |
3311 | ||
5b0311e1 FW |
3312 | /* |
3313 | * First go through the list and put on any pinned groups | |
3314 | * in order to give them the best chance of going on. | |
3315 | */ | |
3cbaa590 | 3316 | if (is_active & EVENT_PINNED) |
6e37738a | 3317 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3318 | |
3319 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3320 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3321 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3322 | } |
3323 | ||
329c0e01 | 3324 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3325 | enum event_type_t event_type, |
3326 | struct task_struct *task) | |
329c0e01 FW |
3327 | { |
3328 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3329 | ||
e5d1367f | 3330 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3331 | } |
3332 | ||
e5d1367f SE |
3333 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3334 | struct task_struct *task) | |
235c7fc7 | 3335 | { |
108b02cf | 3336 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3337 | |
108b02cf | 3338 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3339 | if (cpuctx->task_ctx == ctx) |
3340 | return; | |
3341 | ||
facc4307 | 3342 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3343 | /* |
3344 | * We must check ctx->nr_events while holding ctx->lock, such | |
3345 | * that we serialize against perf_install_in_context(). | |
3346 | */ | |
3347 | if (!ctx->nr_events) | |
3348 | goto unlock; | |
3349 | ||
1b9a644f | 3350 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3351 | /* |
3352 | * We want to keep the following priority order: | |
3353 | * cpu pinned (that don't need to move), task pinned, | |
3354 | * cpu flexible, task flexible. | |
fe45bafb AS |
3355 | * |
3356 | * However, if task's ctx is not carrying any pinned | |
3357 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3358 | */ |
8e1a2031 | 3359 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3360 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3361 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3362 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3363 | |
3364 | unlock: | |
facc4307 | 3365 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3366 | } |
3367 | ||
8dc85d54 PZ |
3368 | /* |
3369 | * Called from scheduler to add the events of the current task | |
3370 | * with interrupts disabled. | |
3371 | * | |
3372 | * We restore the event value and then enable it. | |
3373 | * | |
3374 | * This does not protect us against NMI, but enable() | |
3375 | * sets the enabled bit in the control field of event _before_ | |
3376 | * accessing the event control register. If a NMI hits, then it will | |
3377 | * keep the event running. | |
3378 | */ | |
ab0cce56 JO |
3379 | void __perf_event_task_sched_in(struct task_struct *prev, |
3380 | struct task_struct *task) | |
8dc85d54 PZ |
3381 | { |
3382 | struct perf_event_context *ctx; | |
3383 | int ctxn; | |
3384 | ||
7e41d177 PZ |
3385 | /* |
3386 | * If cgroup events exist on this CPU, then we need to check if we have | |
3387 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3388 | * | |
3389 | * Since cgroup events are CPU events, we must schedule these in before | |
3390 | * we schedule in the task events. | |
3391 | */ | |
3392 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3393 | perf_cgroup_sched_in(prev, task); | |
3394 | ||
8dc85d54 PZ |
3395 | for_each_task_context_nr(ctxn) { |
3396 | ctx = task->perf_event_ctxp[ctxn]; | |
3397 | if (likely(!ctx)) | |
3398 | continue; | |
3399 | ||
e5d1367f | 3400 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3401 | } |
d010b332 | 3402 | |
45ac1403 AH |
3403 | if (atomic_read(&nr_switch_events)) |
3404 | perf_event_switch(task, prev, true); | |
3405 | ||
ba532500 YZ |
3406 | if (__this_cpu_read(perf_sched_cb_usages)) |
3407 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3408 | } |
3409 | ||
abd50713 PZ |
3410 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3411 | { | |
3412 | u64 frequency = event->attr.sample_freq; | |
3413 | u64 sec = NSEC_PER_SEC; | |
3414 | u64 divisor, dividend; | |
3415 | ||
3416 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3417 | ||
3418 | count_fls = fls64(count); | |
3419 | nsec_fls = fls64(nsec); | |
3420 | frequency_fls = fls64(frequency); | |
3421 | sec_fls = 30; | |
3422 | ||
3423 | /* | |
3424 | * We got @count in @nsec, with a target of sample_freq HZ | |
3425 | * the target period becomes: | |
3426 | * | |
3427 | * @count * 10^9 | |
3428 | * period = ------------------- | |
3429 | * @nsec * sample_freq | |
3430 | * | |
3431 | */ | |
3432 | ||
3433 | /* | |
3434 | * Reduce accuracy by one bit such that @a and @b converge | |
3435 | * to a similar magnitude. | |
3436 | */ | |
fe4b04fa | 3437 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3438 | do { \ |
3439 | if (a##_fls > b##_fls) { \ | |
3440 | a >>= 1; \ | |
3441 | a##_fls--; \ | |
3442 | } else { \ | |
3443 | b >>= 1; \ | |
3444 | b##_fls--; \ | |
3445 | } \ | |
3446 | } while (0) | |
3447 | ||
3448 | /* | |
3449 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3450 | * the other, so that finally we can do a u64/u64 division. | |
3451 | */ | |
3452 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3453 | REDUCE_FLS(nsec, frequency); | |
3454 | REDUCE_FLS(sec, count); | |
3455 | } | |
3456 | ||
3457 | if (count_fls + sec_fls > 64) { | |
3458 | divisor = nsec * frequency; | |
3459 | ||
3460 | while (count_fls + sec_fls > 64) { | |
3461 | REDUCE_FLS(count, sec); | |
3462 | divisor >>= 1; | |
3463 | } | |
3464 | ||
3465 | dividend = count * sec; | |
3466 | } else { | |
3467 | dividend = count * sec; | |
3468 | ||
3469 | while (nsec_fls + frequency_fls > 64) { | |
3470 | REDUCE_FLS(nsec, frequency); | |
3471 | dividend >>= 1; | |
3472 | } | |
3473 | ||
3474 | divisor = nsec * frequency; | |
3475 | } | |
3476 | ||
f6ab91ad PZ |
3477 | if (!divisor) |
3478 | return dividend; | |
3479 | ||
abd50713 PZ |
3480 | return div64_u64(dividend, divisor); |
3481 | } | |
3482 | ||
e050e3f0 SE |
3483 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3484 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3485 | ||
f39d47ff | 3486 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3487 | { |
cdd6c482 | 3488 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3489 | s64 period, sample_period; |
bd2b5b12 PZ |
3490 | s64 delta; |
3491 | ||
abd50713 | 3492 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3493 | |
3494 | delta = (s64)(period - hwc->sample_period); | |
3495 | delta = (delta + 7) / 8; /* low pass filter */ | |
3496 | ||
3497 | sample_period = hwc->sample_period + delta; | |
3498 | ||
3499 | if (!sample_period) | |
3500 | sample_period = 1; | |
3501 | ||
bd2b5b12 | 3502 | hwc->sample_period = sample_period; |
abd50713 | 3503 | |
e7850595 | 3504 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3505 | if (disable) |
3506 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3507 | ||
e7850595 | 3508 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3509 | |
3510 | if (disable) | |
3511 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3512 | } |
bd2b5b12 PZ |
3513 | } |
3514 | ||
e050e3f0 SE |
3515 | /* |
3516 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3517 | * events. At the same time, make sure, having freq events does not change | |
3518 | * the rate of unthrottling as that would introduce bias. | |
3519 | */ | |
3520 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3521 | int needs_unthr) | |
60db5e09 | 3522 | { |
cdd6c482 IM |
3523 | struct perf_event *event; |
3524 | struct hw_perf_event *hwc; | |
e050e3f0 | 3525 | u64 now, period = TICK_NSEC; |
abd50713 | 3526 | s64 delta; |
60db5e09 | 3527 | |
e050e3f0 SE |
3528 | /* |
3529 | * only need to iterate over all events iff: | |
3530 | * - context have events in frequency mode (needs freq adjust) | |
3531 | * - there are events to unthrottle on this cpu | |
3532 | */ | |
3533 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3534 | return; |
3535 | ||
e050e3f0 | 3536 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3537 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3538 | |
03541f8b | 3539 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3540 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3541 | continue; |
3542 | ||
5632ab12 | 3543 | if (!event_filter_match(event)) |
5d27c23d PZ |
3544 | continue; |
3545 | ||
44377277 AS |
3546 | perf_pmu_disable(event->pmu); |
3547 | ||
cdd6c482 | 3548 | hwc = &event->hw; |
6a24ed6c | 3549 | |
ae23bff1 | 3550 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3551 | hwc->interrupts = 0; |
cdd6c482 | 3552 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3553 | event->pmu->start(event, 0); |
a78ac325 PZ |
3554 | } |
3555 | ||
cdd6c482 | 3556 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3557 | goto next; |
60db5e09 | 3558 | |
e050e3f0 SE |
3559 | /* |
3560 | * stop the event and update event->count | |
3561 | */ | |
3562 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3563 | ||
e7850595 | 3564 | now = local64_read(&event->count); |
abd50713 PZ |
3565 | delta = now - hwc->freq_count_stamp; |
3566 | hwc->freq_count_stamp = now; | |
60db5e09 | 3567 | |
e050e3f0 SE |
3568 | /* |
3569 | * restart the event | |
3570 | * reload only if value has changed | |
f39d47ff SE |
3571 | * we have stopped the event so tell that |
3572 | * to perf_adjust_period() to avoid stopping it | |
3573 | * twice. | |
e050e3f0 | 3574 | */ |
abd50713 | 3575 | if (delta > 0) |
f39d47ff | 3576 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3577 | |
3578 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3579 | next: |
3580 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3581 | } |
e050e3f0 | 3582 | |
f39d47ff | 3583 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3584 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3585 | } |
3586 | ||
235c7fc7 | 3587 | /* |
8703a7cf | 3588 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3589 | */ |
8703a7cf | 3590 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3591 | { |
dddd3379 TG |
3592 | /* |
3593 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3594 | * disabled by the inheritance code. | |
3595 | */ | |
8703a7cf PZ |
3596 | if (ctx->rotate_disable) |
3597 | return; | |
8e1a2031 | 3598 | |
8703a7cf PZ |
3599 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3600 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3601 | } |
3602 | ||
8d5bce0c PZ |
3603 | static inline struct perf_event * |
3604 | ctx_first_active(struct perf_event_context *ctx) | |
235c7fc7 | 3605 | { |
8d5bce0c PZ |
3606 | return list_first_entry_or_null(&ctx->flexible_active, |
3607 | struct perf_event, active_list); | |
3608 | } | |
3609 | ||
3610 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
3611 | { | |
3612 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
3613 | bool cpu_rotate = false, task_rotate = false; | |
8dc85d54 | 3614 | struct perf_event_context *ctx = NULL; |
8d5bce0c PZ |
3615 | |
3616 | /* | |
3617 | * Since we run this from IRQ context, nobody can install new | |
3618 | * events, thus the event count values are stable. | |
3619 | */ | |
7fc23a53 | 3620 | |
b5ab4cd5 | 3621 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 | 3622 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
8d5bce0c | 3623 | cpu_rotate = true; |
b5ab4cd5 | 3624 | } |
235c7fc7 | 3625 | |
8dc85d54 | 3626 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3627 | if (ctx && ctx->nr_events) { |
b5ab4cd5 | 3628 | if (ctx->nr_events != ctx->nr_active) |
8d5bce0c | 3629 | task_rotate = true; |
b5ab4cd5 | 3630 | } |
9717e6cd | 3631 | |
8d5bce0c PZ |
3632 | if (!(cpu_rotate || task_rotate)) |
3633 | return false; | |
0f5a2601 | 3634 | |
facc4307 | 3635 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3636 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3637 | |
8d5bce0c PZ |
3638 | if (task_rotate) |
3639 | task_event = ctx_first_active(ctx); | |
3640 | if (cpu_rotate) | |
3641 | cpu_event = ctx_first_active(&cpuctx->ctx); | |
8703a7cf | 3642 | |
8d5bce0c PZ |
3643 | /* |
3644 | * As per the order given at ctx_resched() first 'pop' task flexible | |
3645 | * and then, if needed CPU flexible. | |
3646 | */ | |
3647 | if (task_event || (ctx && cpu_event)) | |
e050e3f0 | 3648 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); |
8d5bce0c PZ |
3649 | if (cpu_event) |
3650 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3651 | |
8d5bce0c PZ |
3652 | if (task_event) |
3653 | rotate_ctx(ctx, task_event); | |
3654 | if (cpu_event) | |
3655 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 3656 | |
e050e3f0 | 3657 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3658 | |
0f5a2601 PZ |
3659 | perf_pmu_enable(cpuctx->ctx.pmu); |
3660 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 3661 | |
8d5bce0c | 3662 | return true; |
e9d2b064 PZ |
3663 | } |
3664 | ||
3665 | void perf_event_task_tick(void) | |
3666 | { | |
2fde4f94 MR |
3667 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3668 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3669 | int throttled; |
b5ab4cd5 | 3670 | |
16444645 | 3671 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3672 | |
e050e3f0 SE |
3673 | __this_cpu_inc(perf_throttled_seq); |
3674 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3675 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3676 | |
2fde4f94 | 3677 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3678 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3679 | } |
3680 | ||
889ff015 FW |
3681 | static int event_enable_on_exec(struct perf_event *event, |
3682 | struct perf_event_context *ctx) | |
3683 | { | |
3684 | if (!event->attr.enable_on_exec) | |
3685 | return 0; | |
3686 | ||
3687 | event->attr.enable_on_exec = 0; | |
3688 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3689 | return 0; | |
3690 | ||
0d3d73aa | 3691 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3692 | |
3693 | return 1; | |
3694 | } | |
3695 | ||
57e7986e | 3696 | /* |
cdd6c482 | 3697 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3698 | * This expects task == current. |
3699 | */ | |
c1274499 | 3700 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3701 | { |
c1274499 | 3702 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3703 | enum event_type_t event_type = 0; |
3e349507 | 3704 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3705 | struct perf_event *event; |
57e7986e PM |
3706 | unsigned long flags; |
3707 | int enabled = 0; | |
3708 | ||
3709 | local_irq_save(flags); | |
c1274499 | 3710 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3711 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3712 | goto out; |
3713 | ||
3e349507 PZ |
3714 | cpuctx = __get_cpu_context(ctx); |
3715 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3716 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3717 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3718 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3719 | event_type |= get_event_type(event); |
3720 | } | |
57e7986e PM |
3721 | |
3722 | /* | |
3e349507 | 3723 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3724 | */ |
3e349507 | 3725 | if (enabled) { |
211de6eb | 3726 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3727 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3728 | } else { |
3729 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3730 | } |
3731 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3732 | |
9ed6060d | 3733 | out: |
57e7986e | 3734 | local_irq_restore(flags); |
211de6eb PZ |
3735 | |
3736 | if (clone_ctx) | |
3737 | put_ctx(clone_ctx); | |
57e7986e PM |
3738 | } |
3739 | ||
0492d4c5 PZ |
3740 | struct perf_read_data { |
3741 | struct perf_event *event; | |
3742 | bool group; | |
7d88962e | 3743 | int ret; |
0492d4c5 PZ |
3744 | }; |
3745 | ||
451d24d1 | 3746 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3747 | { |
d6a2f903 DCC |
3748 | u16 local_pkg, event_pkg; |
3749 | ||
3750 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3751 | int local_cpu = smp_processor_id(); |
3752 | ||
3753 | event_pkg = topology_physical_package_id(event_cpu); | |
3754 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3755 | |
3756 | if (event_pkg == local_pkg) | |
3757 | return local_cpu; | |
3758 | } | |
3759 | ||
3760 | return event_cpu; | |
3761 | } | |
3762 | ||
0793a61d | 3763 | /* |
cdd6c482 | 3764 | * Cross CPU call to read the hardware event |
0793a61d | 3765 | */ |
cdd6c482 | 3766 | static void __perf_event_read(void *info) |
0793a61d | 3767 | { |
0492d4c5 PZ |
3768 | struct perf_read_data *data = info; |
3769 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3770 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3771 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3772 | struct pmu *pmu = event->pmu; |
621a01ea | 3773 | |
e1ac3614 PM |
3774 | /* |
3775 | * If this is a task context, we need to check whether it is | |
3776 | * the current task context of this cpu. If not it has been | |
3777 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3778 | * event->count would have been updated to a recent sample |
3779 | * when the event was scheduled out. | |
e1ac3614 PM |
3780 | */ |
3781 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3782 | return; | |
3783 | ||
e625cce1 | 3784 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3785 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 3786 | update_context_time(ctx); |
e5d1367f SE |
3787 | update_cgrp_time_from_event(event); |
3788 | } | |
0492d4c5 | 3789 | |
0d3d73aa PZ |
3790 | perf_event_update_time(event); |
3791 | if (data->group) | |
3792 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 3793 | |
4a00c16e SB |
3794 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3795 | goto unlock; | |
0492d4c5 | 3796 | |
4a00c16e SB |
3797 | if (!data->group) { |
3798 | pmu->read(event); | |
3799 | data->ret = 0; | |
0492d4c5 | 3800 | goto unlock; |
4a00c16e SB |
3801 | } |
3802 | ||
3803 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3804 | ||
3805 | pmu->read(event); | |
0492d4c5 | 3806 | |
8343aae6 | 3807 | list_for_each_entry(sub, &event->sibling_list, sibling_list) { |
4a00c16e SB |
3808 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3809 | /* | |
3810 | * Use sibling's PMU rather than @event's since | |
3811 | * sibling could be on different (eg: software) PMU. | |
3812 | */ | |
0492d4c5 | 3813 | sub->pmu->read(sub); |
4a00c16e | 3814 | } |
0492d4c5 | 3815 | } |
4a00c16e SB |
3816 | |
3817 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3818 | |
3819 | unlock: | |
e625cce1 | 3820 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3821 | } |
3822 | ||
b5e58793 PZ |
3823 | static inline u64 perf_event_count(struct perf_event *event) |
3824 | { | |
c39a0e2c | 3825 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
3826 | } |
3827 | ||
ffe8690c KX |
3828 | /* |
3829 | * NMI-safe method to read a local event, that is an event that | |
3830 | * is: | |
3831 | * - either for the current task, or for this CPU | |
3832 | * - does not have inherit set, for inherited task events | |
3833 | * will not be local and we cannot read them atomically | |
3834 | * - must not have a pmu::count method | |
3835 | */ | |
7d9285e8 YS |
3836 | int perf_event_read_local(struct perf_event *event, u64 *value, |
3837 | u64 *enabled, u64 *running) | |
ffe8690c KX |
3838 | { |
3839 | unsigned long flags; | |
f91840a3 | 3840 | int ret = 0; |
ffe8690c KX |
3841 | |
3842 | /* | |
3843 | * Disabling interrupts avoids all counter scheduling (context | |
3844 | * switches, timer based rotation and IPIs). | |
3845 | */ | |
3846 | local_irq_save(flags); | |
3847 | ||
ffe8690c KX |
3848 | /* |
3849 | * It must not be an event with inherit set, we cannot read | |
3850 | * all child counters from atomic context. | |
3851 | */ | |
f91840a3 AS |
3852 | if (event->attr.inherit) { |
3853 | ret = -EOPNOTSUPP; | |
3854 | goto out; | |
3855 | } | |
ffe8690c | 3856 | |
f91840a3 AS |
3857 | /* If this is a per-task event, it must be for current */ |
3858 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
3859 | event->hw.target != current) { | |
3860 | ret = -EINVAL; | |
3861 | goto out; | |
3862 | } | |
3863 | ||
3864 | /* If this is a per-CPU event, it must be for this CPU */ | |
3865 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
3866 | event->cpu != smp_processor_id()) { | |
3867 | ret = -EINVAL; | |
3868 | goto out; | |
3869 | } | |
ffe8690c KX |
3870 | |
3871 | /* | |
3872 | * If the event is currently on this CPU, its either a per-task event, | |
3873 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3874 | * oncpu == -1). | |
3875 | */ | |
3876 | if (event->oncpu == smp_processor_id()) | |
3877 | event->pmu->read(event); | |
3878 | ||
f91840a3 | 3879 | *value = local64_read(&event->count); |
0d3d73aa PZ |
3880 | if (enabled || running) { |
3881 | u64 now = event->shadow_ctx_time + perf_clock(); | |
3882 | u64 __enabled, __running; | |
3883 | ||
3884 | __perf_update_times(event, now, &__enabled, &__running); | |
3885 | if (enabled) | |
3886 | *enabled = __enabled; | |
3887 | if (running) | |
3888 | *running = __running; | |
3889 | } | |
f91840a3 | 3890 | out: |
ffe8690c KX |
3891 | local_irq_restore(flags); |
3892 | ||
f91840a3 | 3893 | return ret; |
ffe8690c KX |
3894 | } |
3895 | ||
7d88962e | 3896 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3897 | { |
0c1cbc18 | 3898 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 3899 | int event_cpu, ret = 0; |
7d88962e | 3900 | |
0793a61d | 3901 | /* |
cdd6c482 IM |
3902 | * If event is enabled and currently active on a CPU, update the |
3903 | * value in the event structure: | |
0793a61d | 3904 | */ |
0c1cbc18 PZ |
3905 | again: |
3906 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
3907 | struct perf_read_data data; | |
3908 | ||
3909 | /* | |
3910 | * Orders the ->state and ->oncpu loads such that if we see | |
3911 | * ACTIVE we must also see the right ->oncpu. | |
3912 | * | |
3913 | * Matches the smp_wmb() from event_sched_in(). | |
3914 | */ | |
3915 | smp_rmb(); | |
d6a2f903 | 3916 | |
451d24d1 PZ |
3917 | event_cpu = READ_ONCE(event->oncpu); |
3918 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
3919 | return 0; | |
3920 | ||
0c1cbc18 PZ |
3921 | data = (struct perf_read_data){ |
3922 | .event = event, | |
3923 | .group = group, | |
3924 | .ret = 0, | |
3925 | }; | |
3926 | ||
451d24d1 PZ |
3927 | preempt_disable(); |
3928 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 3929 | |
58763148 PZ |
3930 | /* |
3931 | * Purposely ignore the smp_call_function_single() return | |
3932 | * value. | |
3933 | * | |
451d24d1 | 3934 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
3935 | * scheduled out and that will have updated the event count. |
3936 | * | |
3937 | * Therefore, either way, we'll have an up-to-date event count | |
3938 | * after this. | |
3939 | */ | |
451d24d1 PZ |
3940 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
3941 | preempt_enable(); | |
58763148 | 3942 | ret = data.ret; |
0c1cbc18 PZ |
3943 | |
3944 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
3945 | struct perf_event_context *ctx = event->ctx; |
3946 | unsigned long flags; | |
3947 | ||
e625cce1 | 3948 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
3949 | state = event->state; |
3950 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
3951 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
3952 | goto again; | |
3953 | } | |
3954 | ||
c530ccd9 | 3955 | /* |
0c1cbc18 PZ |
3956 | * May read while context is not active (e.g., thread is |
3957 | * blocked), in that case we cannot update context time | |
c530ccd9 | 3958 | */ |
0c1cbc18 | 3959 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 3960 | update_context_time(ctx); |
e5d1367f SE |
3961 | update_cgrp_time_from_event(event); |
3962 | } | |
0c1cbc18 | 3963 | |
0d3d73aa | 3964 | perf_event_update_time(event); |
0492d4c5 | 3965 | if (group) |
0d3d73aa | 3966 | perf_event_update_sibling_time(event); |
e625cce1 | 3967 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3968 | } |
7d88962e SB |
3969 | |
3970 | return ret; | |
0793a61d TG |
3971 | } |
3972 | ||
a63eaf34 | 3973 | /* |
cdd6c482 | 3974 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3975 | */ |
eb184479 | 3976 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3977 | { |
e625cce1 | 3978 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3979 | mutex_init(&ctx->mutex); |
2fde4f94 | 3980 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
3981 | perf_event_groups_init(&ctx->pinned_groups); |
3982 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 3983 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
3984 | INIT_LIST_HEAD(&ctx->pinned_active); |
3985 | INIT_LIST_HEAD(&ctx->flexible_active); | |
a63eaf34 | 3986 | atomic_set(&ctx->refcount, 1); |
eb184479 PZ |
3987 | } |
3988 | ||
3989 | static struct perf_event_context * | |
3990 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3991 | { | |
3992 | struct perf_event_context *ctx; | |
3993 | ||
3994 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3995 | if (!ctx) | |
3996 | return NULL; | |
3997 | ||
3998 | __perf_event_init_context(ctx); | |
3999 | if (task) { | |
4000 | ctx->task = task; | |
4001 | get_task_struct(task); | |
0793a61d | 4002 | } |
eb184479 PZ |
4003 | ctx->pmu = pmu; |
4004 | ||
4005 | return ctx; | |
a63eaf34 PM |
4006 | } |
4007 | ||
2ebd4ffb MH |
4008 | static struct task_struct * |
4009 | find_lively_task_by_vpid(pid_t vpid) | |
4010 | { | |
4011 | struct task_struct *task; | |
0793a61d TG |
4012 | |
4013 | rcu_read_lock(); | |
2ebd4ffb | 4014 | if (!vpid) |
0793a61d TG |
4015 | task = current; |
4016 | else | |
2ebd4ffb | 4017 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4018 | if (task) |
4019 | get_task_struct(task); | |
4020 | rcu_read_unlock(); | |
4021 | ||
4022 | if (!task) | |
4023 | return ERR_PTR(-ESRCH); | |
4024 | ||
2ebd4ffb | 4025 | return task; |
2ebd4ffb MH |
4026 | } |
4027 | ||
fe4b04fa PZ |
4028 | /* |
4029 | * Returns a matching context with refcount and pincount. | |
4030 | */ | |
108b02cf | 4031 | static struct perf_event_context * |
4af57ef2 YZ |
4032 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4033 | struct perf_event *event) | |
0793a61d | 4034 | { |
211de6eb | 4035 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4036 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4037 | void *task_ctx_data = NULL; |
25346b93 | 4038 | unsigned long flags; |
8dc85d54 | 4039 | int ctxn, err; |
4af57ef2 | 4040 | int cpu = event->cpu; |
0793a61d | 4041 | |
22a4ec72 | 4042 | if (!task) { |
cdd6c482 | 4043 | /* Must be root to operate on a CPU event: */ |
0764771d | 4044 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
4045 | return ERR_PTR(-EACCES); |
4046 | ||
108b02cf | 4047 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4048 | ctx = &cpuctx->ctx; |
c93f7669 | 4049 | get_ctx(ctx); |
fe4b04fa | 4050 | ++ctx->pin_count; |
0793a61d | 4051 | |
0793a61d TG |
4052 | return ctx; |
4053 | } | |
4054 | ||
8dc85d54 PZ |
4055 | err = -EINVAL; |
4056 | ctxn = pmu->task_ctx_nr; | |
4057 | if (ctxn < 0) | |
4058 | goto errout; | |
4059 | ||
4af57ef2 YZ |
4060 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4061 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4062 | if (!task_ctx_data) { | |
4063 | err = -ENOMEM; | |
4064 | goto errout; | |
4065 | } | |
4066 | } | |
4067 | ||
9ed6060d | 4068 | retry: |
8dc85d54 | 4069 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4070 | if (ctx) { |
211de6eb | 4071 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4072 | ++ctx->pin_count; |
4af57ef2 YZ |
4073 | |
4074 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4075 | ctx->task_ctx_data = task_ctx_data; | |
4076 | task_ctx_data = NULL; | |
4077 | } | |
e625cce1 | 4078 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4079 | |
4080 | if (clone_ctx) | |
4081 | put_ctx(clone_ctx); | |
9137fb28 | 4082 | } else { |
eb184479 | 4083 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4084 | err = -ENOMEM; |
4085 | if (!ctx) | |
4086 | goto errout; | |
eb184479 | 4087 | |
4af57ef2 YZ |
4088 | if (task_ctx_data) { |
4089 | ctx->task_ctx_data = task_ctx_data; | |
4090 | task_ctx_data = NULL; | |
4091 | } | |
4092 | ||
dbe08d82 ON |
4093 | err = 0; |
4094 | mutex_lock(&task->perf_event_mutex); | |
4095 | /* | |
4096 | * If it has already passed perf_event_exit_task(). | |
4097 | * we must see PF_EXITING, it takes this mutex too. | |
4098 | */ | |
4099 | if (task->flags & PF_EXITING) | |
4100 | err = -ESRCH; | |
4101 | else if (task->perf_event_ctxp[ctxn]) | |
4102 | err = -EAGAIN; | |
fe4b04fa | 4103 | else { |
9137fb28 | 4104 | get_ctx(ctx); |
fe4b04fa | 4105 | ++ctx->pin_count; |
dbe08d82 | 4106 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4107 | } |
dbe08d82 ON |
4108 | mutex_unlock(&task->perf_event_mutex); |
4109 | ||
4110 | if (unlikely(err)) { | |
9137fb28 | 4111 | put_ctx(ctx); |
dbe08d82 ON |
4112 | |
4113 | if (err == -EAGAIN) | |
4114 | goto retry; | |
4115 | goto errout; | |
a63eaf34 PM |
4116 | } |
4117 | } | |
4118 | ||
4af57ef2 | 4119 | kfree(task_ctx_data); |
0793a61d | 4120 | return ctx; |
c93f7669 | 4121 | |
9ed6060d | 4122 | errout: |
4af57ef2 | 4123 | kfree(task_ctx_data); |
c93f7669 | 4124 | return ERR_PTR(err); |
0793a61d TG |
4125 | } |
4126 | ||
6fb2915d | 4127 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4128 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4129 | |
cdd6c482 | 4130 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4131 | { |
cdd6c482 | 4132 | struct perf_event *event; |
592903cd | 4133 | |
cdd6c482 IM |
4134 | event = container_of(head, struct perf_event, rcu_head); |
4135 | if (event->ns) | |
4136 | put_pid_ns(event->ns); | |
6fb2915d | 4137 | perf_event_free_filter(event); |
cdd6c482 | 4138 | kfree(event); |
592903cd PZ |
4139 | } |
4140 | ||
b69cf536 PZ |
4141 | static void ring_buffer_attach(struct perf_event *event, |
4142 | struct ring_buffer *rb); | |
925d519a | 4143 | |
f2fb6bef KL |
4144 | static void detach_sb_event(struct perf_event *event) |
4145 | { | |
4146 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4147 | ||
4148 | raw_spin_lock(&pel->lock); | |
4149 | list_del_rcu(&event->sb_list); | |
4150 | raw_spin_unlock(&pel->lock); | |
4151 | } | |
4152 | ||
a4f144eb | 4153 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4154 | { |
a4f144eb DCC |
4155 | struct perf_event_attr *attr = &event->attr; |
4156 | ||
f2fb6bef | 4157 | if (event->parent) |
a4f144eb | 4158 | return false; |
f2fb6bef KL |
4159 | |
4160 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4161 | return false; |
f2fb6bef | 4162 | |
a4f144eb DCC |
4163 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4164 | attr->comm || attr->comm_exec || | |
4165 | attr->task || | |
4166 | attr->context_switch) | |
4167 | return true; | |
4168 | return false; | |
4169 | } | |
4170 | ||
4171 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4172 | { | |
4173 | if (is_sb_event(event)) | |
4174 | detach_sb_event(event); | |
f2fb6bef KL |
4175 | } |
4176 | ||
4beb31f3 | 4177 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4178 | { |
4beb31f3 FW |
4179 | if (event->parent) |
4180 | return; | |
4181 | ||
4beb31f3 FW |
4182 | if (is_cgroup_event(event)) |
4183 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4184 | } | |
925d519a | 4185 | |
555e0c1e FW |
4186 | #ifdef CONFIG_NO_HZ_FULL |
4187 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4188 | #endif | |
4189 | ||
4190 | static void unaccount_freq_event_nohz(void) | |
4191 | { | |
4192 | #ifdef CONFIG_NO_HZ_FULL | |
4193 | spin_lock(&nr_freq_lock); | |
4194 | if (atomic_dec_and_test(&nr_freq_events)) | |
4195 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4196 | spin_unlock(&nr_freq_lock); | |
4197 | #endif | |
4198 | } | |
4199 | ||
4200 | static void unaccount_freq_event(void) | |
4201 | { | |
4202 | if (tick_nohz_full_enabled()) | |
4203 | unaccount_freq_event_nohz(); | |
4204 | else | |
4205 | atomic_dec(&nr_freq_events); | |
4206 | } | |
4207 | ||
4beb31f3 FW |
4208 | static void unaccount_event(struct perf_event *event) |
4209 | { | |
25432ae9 PZ |
4210 | bool dec = false; |
4211 | ||
4beb31f3 FW |
4212 | if (event->parent) |
4213 | return; | |
4214 | ||
4215 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4216 | dec = true; |
4beb31f3 FW |
4217 | if (event->attr.mmap || event->attr.mmap_data) |
4218 | atomic_dec(&nr_mmap_events); | |
4219 | if (event->attr.comm) | |
4220 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4221 | if (event->attr.namespaces) |
4222 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4223 | if (event->attr.task) |
4224 | atomic_dec(&nr_task_events); | |
948b26b6 | 4225 | if (event->attr.freq) |
555e0c1e | 4226 | unaccount_freq_event(); |
45ac1403 | 4227 | if (event->attr.context_switch) { |
25432ae9 | 4228 | dec = true; |
45ac1403 AH |
4229 | atomic_dec(&nr_switch_events); |
4230 | } | |
4beb31f3 | 4231 | if (is_cgroup_event(event)) |
25432ae9 | 4232 | dec = true; |
4beb31f3 | 4233 | if (has_branch_stack(event)) |
25432ae9 PZ |
4234 | dec = true; |
4235 | ||
9107c89e PZ |
4236 | if (dec) { |
4237 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4238 | schedule_delayed_work(&perf_sched_work, HZ); | |
4239 | } | |
4beb31f3 FW |
4240 | |
4241 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4242 | |
4243 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4244 | } |
925d519a | 4245 | |
9107c89e PZ |
4246 | static void perf_sched_delayed(struct work_struct *work) |
4247 | { | |
4248 | mutex_lock(&perf_sched_mutex); | |
4249 | if (atomic_dec_and_test(&perf_sched_count)) | |
4250 | static_branch_disable(&perf_sched_events); | |
4251 | mutex_unlock(&perf_sched_mutex); | |
4252 | } | |
4253 | ||
bed5b25a AS |
4254 | /* |
4255 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4256 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4257 | * at a time, so we disallow creating events that might conflict, namely: | |
4258 | * | |
4259 | * 1) cpu-wide events in the presence of per-task events, | |
4260 | * 2) per-task events in the presence of cpu-wide events, | |
4261 | * 3) two matching events on the same context. | |
4262 | * | |
4263 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4264 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4265 | */ |
4266 | static int exclusive_event_init(struct perf_event *event) | |
4267 | { | |
4268 | struct pmu *pmu = event->pmu; | |
4269 | ||
4270 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4271 | return 0; | |
4272 | ||
4273 | /* | |
4274 | * Prevent co-existence of per-task and cpu-wide events on the | |
4275 | * same exclusive pmu. | |
4276 | * | |
4277 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4278 | * events on this "exclusive" pmu, positive means there are | |
4279 | * per-task events. | |
4280 | * | |
4281 | * Since this is called in perf_event_alloc() path, event::ctx | |
4282 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4283 | * to mean "per-task event", because unlike other attach states it | |
4284 | * never gets cleared. | |
4285 | */ | |
4286 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4287 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4288 | return -EBUSY; | |
4289 | } else { | |
4290 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4291 | return -EBUSY; | |
4292 | } | |
4293 | ||
4294 | return 0; | |
4295 | } | |
4296 | ||
4297 | static void exclusive_event_destroy(struct perf_event *event) | |
4298 | { | |
4299 | struct pmu *pmu = event->pmu; | |
4300 | ||
4301 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4302 | return; | |
4303 | ||
4304 | /* see comment in exclusive_event_init() */ | |
4305 | if (event->attach_state & PERF_ATTACH_TASK) | |
4306 | atomic_dec(&pmu->exclusive_cnt); | |
4307 | else | |
4308 | atomic_inc(&pmu->exclusive_cnt); | |
4309 | } | |
4310 | ||
4311 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4312 | { | |
3bf6215a | 4313 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4314 | (e1->cpu == e2->cpu || |
4315 | e1->cpu == -1 || | |
4316 | e2->cpu == -1)) | |
4317 | return true; | |
4318 | return false; | |
4319 | } | |
4320 | ||
4321 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4322 | static bool exclusive_event_installable(struct perf_event *event, | |
4323 | struct perf_event_context *ctx) | |
4324 | { | |
4325 | struct perf_event *iter_event; | |
4326 | struct pmu *pmu = event->pmu; | |
4327 | ||
4328 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4329 | return true; | |
4330 | ||
4331 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4332 | if (exclusive_event_match(iter_event, event)) | |
4333 | return false; | |
4334 | } | |
4335 | ||
4336 | return true; | |
4337 | } | |
4338 | ||
375637bc AS |
4339 | static void perf_addr_filters_splice(struct perf_event *event, |
4340 | struct list_head *head); | |
4341 | ||
683ede43 | 4342 | static void _free_event(struct perf_event *event) |
f1600952 | 4343 | { |
e360adbe | 4344 | irq_work_sync(&event->pending); |
925d519a | 4345 | |
4beb31f3 | 4346 | unaccount_event(event); |
9ee318a7 | 4347 | |
76369139 | 4348 | if (event->rb) { |
9bb5d40c PZ |
4349 | /* |
4350 | * Can happen when we close an event with re-directed output. | |
4351 | * | |
4352 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4353 | * over us; possibly making our ring_buffer_put() the last. | |
4354 | */ | |
4355 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4356 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4357 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4358 | } |
4359 | ||
e5d1367f SE |
4360 | if (is_cgroup_event(event)) |
4361 | perf_detach_cgroup(event); | |
4362 | ||
a0733e69 PZ |
4363 | if (!event->parent) { |
4364 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4365 | put_callchain_buffers(); | |
4366 | } | |
4367 | ||
4368 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4369 | perf_addr_filters_splice(event, NULL); |
4370 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4371 | |
4372 | if (event->destroy) | |
4373 | event->destroy(event); | |
4374 | ||
4375 | if (event->ctx) | |
4376 | put_ctx(event->ctx); | |
4377 | ||
62a92c8f AS |
4378 | exclusive_event_destroy(event); |
4379 | module_put(event->pmu->module); | |
a0733e69 PZ |
4380 | |
4381 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4382 | } |
4383 | ||
683ede43 PZ |
4384 | /* |
4385 | * Used to free events which have a known refcount of 1, such as in error paths | |
4386 | * where the event isn't exposed yet and inherited events. | |
4387 | */ | |
4388 | static void free_event(struct perf_event *event) | |
0793a61d | 4389 | { |
683ede43 PZ |
4390 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4391 | "unexpected event refcount: %ld; ptr=%p\n", | |
4392 | atomic_long_read(&event->refcount), event)) { | |
4393 | /* leak to avoid use-after-free */ | |
4394 | return; | |
4395 | } | |
0793a61d | 4396 | |
683ede43 | 4397 | _free_event(event); |
0793a61d TG |
4398 | } |
4399 | ||
a66a3052 | 4400 | /* |
f8697762 | 4401 | * Remove user event from the owner task. |
a66a3052 | 4402 | */ |
f8697762 | 4403 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4404 | { |
8882135b | 4405 | struct task_struct *owner; |
fb0459d7 | 4406 | |
8882135b | 4407 | rcu_read_lock(); |
8882135b | 4408 | /* |
f47c02c0 PZ |
4409 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4410 | * observe !owner it means the list deletion is complete and we can | |
4411 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4412 | * owner->perf_event_mutex. |
4413 | */ | |
506458ef | 4414 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4415 | if (owner) { |
4416 | /* | |
4417 | * Since delayed_put_task_struct() also drops the last | |
4418 | * task reference we can safely take a new reference | |
4419 | * while holding the rcu_read_lock(). | |
4420 | */ | |
4421 | get_task_struct(owner); | |
4422 | } | |
4423 | rcu_read_unlock(); | |
4424 | ||
4425 | if (owner) { | |
f63a8daa PZ |
4426 | /* |
4427 | * If we're here through perf_event_exit_task() we're already | |
4428 | * holding ctx->mutex which would be an inversion wrt. the | |
4429 | * normal lock order. | |
4430 | * | |
4431 | * However we can safely take this lock because its the child | |
4432 | * ctx->mutex. | |
4433 | */ | |
4434 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4435 | ||
8882135b PZ |
4436 | /* |
4437 | * We have to re-check the event->owner field, if it is cleared | |
4438 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4439 | * ensured they're done, and we can proceed with freeing the | |
4440 | * event. | |
4441 | */ | |
f47c02c0 | 4442 | if (event->owner) { |
8882135b | 4443 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4444 | smp_store_release(&event->owner, NULL); |
4445 | } | |
8882135b PZ |
4446 | mutex_unlock(&owner->perf_event_mutex); |
4447 | put_task_struct(owner); | |
4448 | } | |
f8697762 JO |
4449 | } |
4450 | ||
f8697762 JO |
4451 | static void put_event(struct perf_event *event) |
4452 | { | |
f8697762 JO |
4453 | if (!atomic_long_dec_and_test(&event->refcount)) |
4454 | return; | |
4455 | ||
c6e5b732 PZ |
4456 | _free_event(event); |
4457 | } | |
4458 | ||
4459 | /* | |
4460 | * Kill an event dead; while event:refcount will preserve the event | |
4461 | * object, it will not preserve its functionality. Once the last 'user' | |
4462 | * gives up the object, we'll destroy the thing. | |
4463 | */ | |
4464 | int perf_event_release_kernel(struct perf_event *event) | |
4465 | { | |
a4f4bb6d | 4466 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4467 | struct perf_event *child, *tmp; |
82d94856 | 4468 | LIST_HEAD(free_list); |
c6e5b732 | 4469 | |
a4f4bb6d PZ |
4470 | /* |
4471 | * If we got here through err_file: fput(event_file); we will not have | |
4472 | * attached to a context yet. | |
4473 | */ | |
4474 | if (!ctx) { | |
4475 | WARN_ON_ONCE(event->attach_state & | |
4476 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4477 | goto no_ctx; | |
4478 | } | |
4479 | ||
f8697762 JO |
4480 | if (!is_kernel_event(event)) |
4481 | perf_remove_from_owner(event); | |
8882135b | 4482 | |
5fa7c8ec | 4483 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4484 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4485 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4486 | |
a69b0ca4 | 4487 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4488 | /* |
d8a8cfc7 | 4489 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4490 | * anymore. |
683ede43 | 4491 | * |
a69b0ca4 PZ |
4492 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4493 | * also see this, most importantly inherit_event() which will avoid | |
4494 | * placing more children on the list. | |
683ede43 | 4495 | * |
c6e5b732 PZ |
4496 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4497 | * child events. | |
683ede43 | 4498 | */ |
a69b0ca4 PZ |
4499 | event->state = PERF_EVENT_STATE_DEAD; |
4500 | raw_spin_unlock_irq(&ctx->lock); | |
4501 | ||
4502 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4503 | |
c6e5b732 PZ |
4504 | again: |
4505 | mutex_lock(&event->child_mutex); | |
4506 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4507 | |
c6e5b732 PZ |
4508 | /* |
4509 | * Cannot change, child events are not migrated, see the | |
4510 | * comment with perf_event_ctx_lock_nested(). | |
4511 | */ | |
506458ef | 4512 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4513 | /* |
4514 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4515 | * through hoops. We start by grabbing a reference on the ctx. | |
4516 | * | |
4517 | * Since the event cannot get freed while we hold the | |
4518 | * child_mutex, the context must also exist and have a !0 | |
4519 | * reference count. | |
4520 | */ | |
4521 | get_ctx(ctx); | |
4522 | ||
4523 | /* | |
4524 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4525 | * acquire ctx::mutex without fear of it going away. Then we | |
4526 | * can re-acquire child_mutex. | |
4527 | */ | |
4528 | mutex_unlock(&event->child_mutex); | |
4529 | mutex_lock(&ctx->mutex); | |
4530 | mutex_lock(&event->child_mutex); | |
4531 | ||
4532 | /* | |
4533 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4534 | * state, if child is still the first entry, it didn't get freed | |
4535 | * and we can continue doing so. | |
4536 | */ | |
4537 | tmp = list_first_entry_or_null(&event->child_list, | |
4538 | struct perf_event, child_list); | |
4539 | if (tmp == child) { | |
4540 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4541 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4542 | /* |
4543 | * This matches the refcount bump in inherit_event(); | |
4544 | * this can't be the last reference. | |
4545 | */ | |
4546 | put_event(event); | |
4547 | } | |
4548 | ||
4549 | mutex_unlock(&event->child_mutex); | |
4550 | mutex_unlock(&ctx->mutex); | |
4551 | put_ctx(ctx); | |
4552 | goto again; | |
4553 | } | |
4554 | mutex_unlock(&event->child_mutex); | |
4555 | ||
82d94856 PZ |
4556 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
4557 | list_del(&child->child_list); | |
4558 | free_event(child); | |
4559 | } | |
4560 | ||
a4f4bb6d PZ |
4561 | no_ctx: |
4562 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4563 | return 0; |
4564 | } | |
4565 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4566 | ||
8b10c5e2 PZ |
4567 | /* |
4568 | * Called when the last reference to the file is gone. | |
4569 | */ | |
a6fa941d AV |
4570 | static int perf_release(struct inode *inode, struct file *file) |
4571 | { | |
c6e5b732 | 4572 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4573 | return 0; |
fb0459d7 | 4574 | } |
fb0459d7 | 4575 | |
ca0dd44c | 4576 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4577 | { |
cdd6c482 | 4578 | struct perf_event *child; |
e53c0994 PZ |
4579 | u64 total = 0; |
4580 | ||
59ed446f PZ |
4581 | *enabled = 0; |
4582 | *running = 0; | |
4583 | ||
6f10581a | 4584 | mutex_lock(&event->child_mutex); |
01add3ea | 4585 | |
7d88962e | 4586 | (void)perf_event_read(event, false); |
01add3ea SB |
4587 | total += perf_event_count(event); |
4588 | ||
59ed446f PZ |
4589 | *enabled += event->total_time_enabled + |
4590 | atomic64_read(&event->child_total_time_enabled); | |
4591 | *running += event->total_time_running + | |
4592 | atomic64_read(&event->child_total_time_running); | |
4593 | ||
4594 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4595 | (void)perf_event_read(child, false); |
01add3ea | 4596 | total += perf_event_count(child); |
59ed446f PZ |
4597 | *enabled += child->total_time_enabled; |
4598 | *running += child->total_time_running; | |
4599 | } | |
6f10581a | 4600 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4601 | |
4602 | return total; | |
4603 | } | |
ca0dd44c PZ |
4604 | |
4605 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4606 | { | |
4607 | struct perf_event_context *ctx; | |
4608 | u64 count; | |
4609 | ||
4610 | ctx = perf_event_ctx_lock(event); | |
4611 | count = __perf_event_read_value(event, enabled, running); | |
4612 | perf_event_ctx_unlock(event, ctx); | |
4613 | ||
4614 | return count; | |
4615 | } | |
fb0459d7 | 4616 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4617 | |
7d88962e | 4618 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4619 | u64 read_format, u64 *values) |
3dab77fb | 4620 | { |
2aeb1883 | 4621 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4622 | struct perf_event *sub; |
2aeb1883 | 4623 | unsigned long flags; |
fa8c2693 | 4624 | int n = 1; /* skip @nr */ |
7d88962e | 4625 | int ret; |
f63a8daa | 4626 | |
7d88962e SB |
4627 | ret = perf_event_read(leader, true); |
4628 | if (ret) | |
4629 | return ret; | |
abf4868b | 4630 | |
a9cd8194 PZ |
4631 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4632 | ||
fa8c2693 PZ |
4633 | /* |
4634 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4635 | * will be identical to those of the leader, so we only publish one | |
4636 | * set. | |
4637 | */ | |
4638 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4639 | values[n++] += leader->total_time_enabled + | |
4640 | atomic64_read(&leader->child_total_time_enabled); | |
4641 | } | |
3dab77fb | 4642 | |
fa8c2693 PZ |
4643 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4644 | values[n++] += leader->total_time_running + | |
4645 | atomic64_read(&leader->child_total_time_running); | |
4646 | } | |
4647 | ||
4648 | /* | |
4649 | * Write {count,id} tuples for every sibling. | |
4650 | */ | |
4651 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4652 | if (read_format & PERF_FORMAT_ID) |
4653 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4654 | |
8343aae6 | 4655 | list_for_each_entry(sub, &leader->sibling_list, sibling_list) { |
fa8c2693 PZ |
4656 | values[n++] += perf_event_count(sub); |
4657 | if (read_format & PERF_FORMAT_ID) | |
4658 | values[n++] = primary_event_id(sub); | |
4659 | } | |
7d88962e | 4660 | |
2aeb1883 | 4661 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4662 | return 0; |
fa8c2693 | 4663 | } |
3dab77fb | 4664 | |
fa8c2693 PZ |
4665 | static int perf_read_group(struct perf_event *event, |
4666 | u64 read_format, char __user *buf) | |
4667 | { | |
4668 | struct perf_event *leader = event->group_leader, *child; | |
4669 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4670 | int ret; |
fa8c2693 | 4671 | u64 *values; |
3dab77fb | 4672 | |
fa8c2693 | 4673 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4674 | |
fa8c2693 PZ |
4675 | values = kzalloc(event->read_size, GFP_KERNEL); |
4676 | if (!values) | |
4677 | return -ENOMEM; | |
3dab77fb | 4678 | |
fa8c2693 PZ |
4679 | values[0] = 1 + leader->nr_siblings; |
4680 | ||
4681 | /* | |
4682 | * By locking the child_mutex of the leader we effectively | |
4683 | * lock the child list of all siblings.. XXX explain how. | |
4684 | */ | |
4685 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4686 | |
7d88962e SB |
4687 | ret = __perf_read_group_add(leader, read_format, values); |
4688 | if (ret) | |
4689 | goto unlock; | |
4690 | ||
4691 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4692 | ret = __perf_read_group_add(child, read_format, values); | |
4693 | if (ret) | |
4694 | goto unlock; | |
4695 | } | |
abf4868b | 4696 | |
fa8c2693 | 4697 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4698 | |
7d88962e | 4699 | ret = event->read_size; |
fa8c2693 PZ |
4700 | if (copy_to_user(buf, values, event->read_size)) |
4701 | ret = -EFAULT; | |
7d88962e | 4702 | goto out; |
fa8c2693 | 4703 | |
7d88962e SB |
4704 | unlock: |
4705 | mutex_unlock(&leader->child_mutex); | |
4706 | out: | |
fa8c2693 | 4707 | kfree(values); |
abf4868b | 4708 | return ret; |
3dab77fb PZ |
4709 | } |
4710 | ||
b15f495b | 4711 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4712 | u64 read_format, char __user *buf) |
4713 | { | |
59ed446f | 4714 | u64 enabled, running; |
3dab77fb PZ |
4715 | u64 values[4]; |
4716 | int n = 0; | |
4717 | ||
ca0dd44c | 4718 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4719 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4720 | values[n++] = enabled; | |
4721 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4722 | values[n++] = running; | |
3dab77fb | 4723 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4724 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4725 | |
4726 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4727 | return -EFAULT; | |
4728 | ||
4729 | return n * sizeof(u64); | |
4730 | } | |
4731 | ||
dc633982 JO |
4732 | static bool is_event_hup(struct perf_event *event) |
4733 | { | |
4734 | bool no_children; | |
4735 | ||
a69b0ca4 | 4736 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4737 | return false; |
4738 | ||
4739 | mutex_lock(&event->child_mutex); | |
4740 | no_children = list_empty(&event->child_list); | |
4741 | mutex_unlock(&event->child_mutex); | |
4742 | return no_children; | |
4743 | } | |
4744 | ||
0793a61d | 4745 | /* |
cdd6c482 | 4746 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4747 | */ |
4748 | static ssize_t | |
b15f495b | 4749 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4750 | { |
cdd6c482 | 4751 | u64 read_format = event->attr.read_format; |
3dab77fb | 4752 | int ret; |
0793a61d | 4753 | |
3b6f9e5c | 4754 | /* |
cdd6c482 | 4755 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4756 | * error state (i.e. because it was pinned but it couldn't be |
4757 | * scheduled on to the CPU at some point). | |
4758 | */ | |
cdd6c482 | 4759 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4760 | return 0; |
4761 | ||
c320c7b7 | 4762 | if (count < event->read_size) |
3dab77fb PZ |
4763 | return -ENOSPC; |
4764 | ||
cdd6c482 | 4765 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4766 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4767 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4768 | else |
b15f495b | 4769 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4770 | |
3dab77fb | 4771 | return ret; |
0793a61d TG |
4772 | } |
4773 | ||
0793a61d TG |
4774 | static ssize_t |
4775 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4776 | { | |
cdd6c482 | 4777 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4778 | struct perf_event_context *ctx; |
4779 | int ret; | |
0793a61d | 4780 | |
f63a8daa | 4781 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4782 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4783 | perf_event_ctx_unlock(event, ctx); |
4784 | ||
4785 | return ret; | |
0793a61d TG |
4786 | } |
4787 | ||
9dd95748 | 4788 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 4789 | { |
cdd6c482 | 4790 | struct perf_event *event = file->private_data; |
76369139 | 4791 | struct ring_buffer *rb; |
a9a08845 | 4792 | __poll_t events = EPOLLHUP; |
c7138f37 | 4793 | |
e708d7ad | 4794 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4795 | |
dc633982 | 4796 | if (is_event_hup(event)) |
179033b3 | 4797 | return events; |
c7138f37 | 4798 | |
10c6db11 | 4799 | /* |
9bb5d40c PZ |
4800 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4801 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4802 | */ |
4803 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4804 | rb = event->rb; |
4805 | if (rb) | |
76369139 | 4806 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4807 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4808 | return events; |
4809 | } | |
4810 | ||
f63a8daa | 4811 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4812 | { |
7d88962e | 4813 | (void)perf_event_read(event, false); |
e7850595 | 4814 | local64_set(&event->count, 0); |
cdd6c482 | 4815 | perf_event_update_userpage(event); |
3df5edad PZ |
4816 | } |
4817 | ||
c93f7669 | 4818 | /* |
cdd6c482 IM |
4819 | * Holding the top-level event's child_mutex means that any |
4820 | * descendant process that has inherited this event will block | |
8ba289b8 | 4821 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4822 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4823 | */ |
cdd6c482 IM |
4824 | static void perf_event_for_each_child(struct perf_event *event, |
4825 | void (*func)(struct perf_event *)) | |
3df5edad | 4826 | { |
cdd6c482 | 4827 | struct perf_event *child; |
3df5edad | 4828 | |
cdd6c482 | 4829 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4830 | |
cdd6c482 IM |
4831 | mutex_lock(&event->child_mutex); |
4832 | func(event); | |
4833 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4834 | func(child); |
cdd6c482 | 4835 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4836 | } |
4837 | ||
cdd6c482 IM |
4838 | static void perf_event_for_each(struct perf_event *event, |
4839 | void (*func)(struct perf_event *)) | |
3df5edad | 4840 | { |
cdd6c482 IM |
4841 | struct perf_event_context *ctx = event->ctx; |
4842 | struct perf_event *sibling; | |
3df5edad | 4843 | |
f63a8daa PZ |
4844 | lockdep_assert_held(&ctx->mutex); |
4845 | ||
cdd6c482 | 4846 | event = event->group_leader; |
75f937f2 | 4847 | |
cdd6c482 | 4848 | perf_event_for_each_child(event, func); |
8343aae6 | 4849 | list_for_each_entry(sibling, &event->sibling_list, sibling_list) |
724b6daa | 4850 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4851 | } |
4852 | ||
fae3fde6 PZ |
4853 | static void __perf_event_period(struct perf_event *event, |
4854 | struct perf_cpu_context *cpuctx, | |
4855 | struct perf_event_context *ctx, | |
4856 | void *info) | |
c7999c6f | 4857 | { |
fae3fde6 | 4858 | u64 value = *((u64 *)info); |
c7999c6f | 4859 | bool active; |
08247e31 | 4860 | |
cdd6c482 | 4861 | if (event->attr.freq) { |
cdd6c482 | 4862 | event->attr.sample_freq = value; |
08247e31 | 4863 | } else { |
cdd6c482 IM |
4864 | event->attr.sample_period = value; |
4865 | event->hw.sample_period = value; | |
08247e31 | 4866 | } |
bad7192b PZ |
4867 | |
4868 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4869 | if (active) { | |
4870 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4871 | /* |
4872 | * We could be throttled; unthrottle now to avoid the tick | |
4873 | * trying to unthrottle while we already re-started the event. | |
4874 | */ | |
4875 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4876 | event->hw.interrupts = 0; | |
4877 | perf_log_throttle(event, 1); | |
4878 | } | |
bad7192b PZ |
4879 | event->pmu->stop(event, PERF_EF_UPDATE); |
4880 | } | |
4881 | ||
4882 | local64_set(&event->hw.period_left, 0); | |
4883 | ||
4884 | if (active) { | |
4885 | event->pmu->start(event, PERF_EF_RELOAD); | |
4886 | perf_pmu_enable(ctx->pmu); | |
4887 | } | |
c7999c6f PZ |
4888 | } |
4889 | ||
4890 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4891 | { | |
c7999c6f PZ |
4892 | u64 value; |
4893 | ||
4894 | if (!is_sampling_event(event)) | |
4895 | return -EINVAL; | |
4896 | ||
4897 | if (copy_from_user(&value, arg, sizeof(value))) | |
4898 | return -EFAULT; | |
4899 | ||
4900 | if (!value) | |
4901 | return -EINVAL; | |
4902 | ||
4903 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4904 | return -EINVAL; | |
4905 | ||
fae3fde6 | 4906 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4907 | |
c7999c6f | 4908 | return 0; |
08247e31 PZ |
4909 | } |
4910 | ||
ac9721f3 PZ |
4911 | static const struct file_operations perf_fops; |
4912 | ||
2903ff01 | 4913 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4914 | { |
2903ff01 AV |
4915 | struct fd f = fdget(fd); |
4916 | if (!f.file) | |
4917 | return -EBADF; | |
ac9721f3 | 4918 | |
2903ff01 AV |
4919 | if (f.file->f_op != &perf_fops) { |
4920 | fdput(f); | |
4921 | return -EBADF; | |
ac9721f3 | 4922 | } |
2903ff01 AV |
4923 | *p = f; |
4924 | return 0; | |
ac9721f3 PZ |
4925 | } |
4926 | ||
4927 | static int perf_event_set_output(struct perf_event *event, | |
4928 | struct perf_event *output_event); | |
6fb2915d | 4929 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4930 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4931 | |
f63a8daa | 4932 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4933 | { |
cdd6c482 | 4934 | void (*func)(struct perf_event *); |
3df5edad | 4935 | u32 flags = arg; |
d859e29f PM |
4936 | |
4937 | switch (cmd) { | |
cdd6c482 | 4938 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4939 | func = _perf_event_enable; |
d859e29f | 4940 | break; |
cdd6c482 | 4941 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4942 | func = _perf_event_disable; |
79f14641 | 4943 | break; |
cdd6c482 | 4944 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4945 | func = _perf_event_reset; |
6de6a7b9 | 4946 | break; |
3df5edad | 4947 | |
cdd6c482 | 4948 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4949 | return _perf_event_refresh(event, arg); |
08247e31 | 4950 | |
cdd6c482 IM |
4951 | case PERF_EVENT_IOC_PERIOD: |
4952 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4953 | |
cf4957f1 JO |
4954 | case PERF_EVENT_IOC_ID: |
4955 | { | |
4956 | u64 id = primary_event_id(event); | |
4957 | ||
4958 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4959 | return -EFAULT; | |
4960 | return 0; | |
4961 | } | |
4962 | ||
cdd6c482 | 4963 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4964 | { |
ac9721f3 | 4965 | int ret; |
ac9721f3 | 4966 | if (arg != -1) { |
2903ff01 AV |
4967 | struct perf_event *output_event; |
4968 | struct fd output; | |
4969 | ret = perf_fget_light(arg, &output); | |
4970 | if (ret) | |
4971 | return ret; | |
4972 | output_event = output.file->private_data; | |
4973 | ret = perf_event_set_output(event, output_event); | |
4974 | fdput(output); | |
4975 | } else { | |
4976 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4977 | } |
ac9721f3 PZ |
4978 | return ret; |
4979 | } | |
a4be7c27 | 4980 | |
6fb2915d LZ |
4981 | case PERF_EVENT_IOC_SET_FILTER: |
4982 | return perf_event_set_filter(event, (void __user *)arg); | |
4983 | ||
2541517c AS |
4984 | case PERF_EVENT_IOC_SET_BPF: |
4985 | return perf_event_set_bpf_prog(event, arg); | |
4986 | ||
86e7972f WN |
4987 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4988 | struct ring_buffer *rb; | |
4989 | ||
4990 | rcu_read_lock(); | |
4991 | rb = rcu_dereference(event->rb); | |
4992 | if (!rb || !rb->nr_pages) { | |
4993 | rcu_read_unlock(); | |
4994 | return -EINVAL; | |
4995 | } | |
4996 | rb_toggle_paused(rb, !!arg); | |
4997 | rcu_read_unlock(); | |
4998 | return 0; | |
4999 | } | |
f371b304 YS |
5000 | |
5001 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5002 | return perf_event_query_prog_array(event, (void __user *)arg); |
d859e29f | 5003 | default: |
3df5edad | 5004 | return -ENOTTY; |
d859e29f | 5005 | } |
3df5edad PZ |
5006 | |
5007 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5008 | perf_event_for_each(event, func); |
3df5edad | 5009 | else |
cdd6c482 | 5010 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5011 | |
5012 | return 0; | |
d859e29f PM |
5013 | } |
5014 | ||
f63a8daa PZ |
5015 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5016 | { | |
5017 | struct perf_event *event = file->private_data; | |
5018 | struct perf_event_context *ctx; | |
5019 | long ret; | |
5020 | ||
5021 | ctx = perf_event_ctx_lock(event); | |
5022 | ret = _perf_ioctl(event, cmd, arg); | |
5023 | perf_event_ctx_unlock(event, ctx); | |
5024 | ||
5025 | return ret; | |
5026 | } | |
5027 | ||
b3f20785 PM |
5028 | #ifdef CONFIG_COMPAT |
5029 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5030 | unsigned long arg) | |
5031 | { | |
5032 | switch (_IOC_NR(cmd)) { | |
5033 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5034 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
5035 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
5036 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5037 | cmd &= ~IOCSIZE_MASK; | |
5038 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5039 | } | |
5040 | break; | |
5041 | } | |
5042 | return perf_ioctl(file, cmd, arg); | |
5043 | } | |
5044 | #else | |
5045 | # define perf_compat_ioctl NULL | |
5046 | #endif | |
5047 | ||
cdd6c482 | 5048 | int perf_event_task_enable(void) |
771d7cde | 5049 | { |
f63a8daa | 5050 | struct perf_event_context *ctx; |
cdd6c482 | 5051 | struct perf_event *event; |
771d7cde | 5052 | |
cdd6c482 | 5053 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5054 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5055 | ctx = perf_event_ctx_lock(event); | |
5056 | perf_event_for_each_child(event, _perf_event_enable); | |
5057 | perf_event_ctx_unlock(event, ctx); | |
5058 | } | |
cdd6c482 | 5059 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5060 | |
5061 | return 0; | |
5062 | } | |
5063 | ||
cdd6c482 | 5064 | int perf_event_task_disable(void) |
771d7cde | 5065 | { |
f63a8daa | 5066 | struct perf_event_context *ctx; |
cdd6c482 | 5067 | struct perf_event *event; |
771d7cde | 5068 | |
cdd6c482 | 5069 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5070 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5071 | ctx = perf_event_ctx_lock(event); | |
5072 | perf_event_for_each_child(event, _perf_event_disable); | |
5073 | perf_event_ctx_unlock(event, ctx); | |
5074 | } | |
cdd6c482 | 5075 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5076 | |
5077 | return 0; | |
5078 | } | |
5079 | ||
cdd6c482 | 5080 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5081 | { |
a4eaf7f1 PZ |
5082 | if (event->hw.state & PERF_HES_STOPPED) |
5083 | return 0; | |
5084 | ||
cdd6c482 | 5085 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5086 | return 0; |
5087 | ||
35edc2a5 | 5088 | return event->pmu->event_idx(event); |
194002b2 PZ |
5089 | } |
5090 | ||
c4794295 | 5091 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5092 | u64 *now, |
7f310a5d EM |
5093 | u64 *enabled, |
5094 | u64 *running) | |
c4794295 | 5095 | { |
e3f3541c | 5096 | u64 ctx_time; |
c4794295 | 5097 | |
e3f3541c PZ |
5098 | *now = perf_clock(); |
5099 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5100 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5101 | } |
5102 | ||
fa731587 PZ |
5103 | static void perf_event_init_userpage(struct perf_event *event) |
5104 | { | |
5105 | struct perf_event_mmap_page *userpg; | |
5106 | struct ring_buffer *rb; | |
5107 | ||
5108 | rcu_read_lock(); | |
5109 | rb = rcu_dereference(event->rb); | |
5110 | if (!rb) | |
5111 | goto unlock; | |
5112 | ||
5113 | userpg = rb->user_page; | |
5114 | ||
5115 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5116 | userpg->cap_bit0_is_deprecated = 1; | |
5117 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5118 | userpg->data_offset = PAGE_SIZE; |
5119 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5120 | |
5121 | unlock: | |
5122 | rcu_read_unlock(); | |
5123 | } | |
5124 | ||
c1317ec2 AL |
5125 | void __weak arch_perf_update_userpage( |
5126 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5127 | { |
5128 | } | |
5129 | ||
38ff667b PZ |
5130 | /* |
5131 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5132 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5133 | * code calls this from NMI context. | |
5134 | */ | |
cdd6c482 | 5135 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5136 | { |
cdd6c482 | 5137 | struct perf_event_mmap_page *userpg; |
76369139 | 5138 | struct ring_buffer *rb; |
e3f3541c | 5139 | u64 enabled, running, now; |
38ff667b PZ |
5140 | |
5141 | rcu_read_lock(); | |
5ec4c599 PZ |
5142 | rb = rcu_dereference(event->rb); |
5143 | if (!rb) | |
5144 | goto unlock; | |
5145 | ||
0d641208 EM |
5146 | /* |
5147 | * compute total_time_enabled, total_time_running | |
5148 | * based on snapshot values taken when the event | |
5149 | * was last scheduled in. | |
5150 | * | |
5151 | * we cannot simply called update_context_time() | |
5152 | * because of locking issue as we can be called in | |
5153 | * NMI context | |
5154 | */ | |
e3f3541c | 5155 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5156 | |
76369139 | 5157 | userpg = rb->user_page; |
7b732a75 PZ |
5158 | /* |
5159 | * Disable preemption so as to not let the corresponding user-space | |
5160 | * spin too long if we get preempted. | |
5161 | */ | |
5162 | preempt_disable(); | |
37d81828 | 5163 | ++userpg->lock; |
92f22a38 | 5164 | barrier(); |
cdd6c482 | 5165 | userpg->index = perf_event_index(event); |
b5e58793 | 5166 | userpg->offset = perf_event_count(event); |
365a4038 | 5167 | if (userpg->index) |
e7850595 | 5168 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5169 | |
0d641208 | 5170 | userpg->time_enabled = enabled + |
cdd6c482 | 5171 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5172 | |
0d641208 | 5173 | userpg->time_running = running + |
cdd6c482 | 5174 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5175 | |
c1317ec2 | 5176 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5177 | |
92f22a38 | 5178 | barrier(); |
37d81828 | 5179 | ++userpg->lock; |
7b732a75 | 5180 | preempt_enable(); |
38ff667b | 5181 | unlock: |
7b732a75 | 5182 | rcu_read_unlock(); |
37d81828 | 5183 | } |
82975c46 | 5184 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5185 | |
11bac800 | 5186 | static int perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5187 | { |
11bac800 | 5188 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 5189 | struct ring_buffer *rb; |
906010b2 PZ |
5190 | int ret = VM_FAULT_SIGBUS; |
5191 | ||
5192 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5193 | if (vmf->pgoff == 0) | |
5194 | ret = 0; | |
5195 | return ret; | |
5196 | } | |
5197 | ||
5198 | rcu_read_lock(); | |
76369139 FW |
5199 | rb = rcu_dereference(event->rb); |
5200 | if (!rb) | |
906010b2 PZ |
5201 | goto unlock; |
5202 | ||
5203 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5204 | goto unlock; | |
5205 | ||
76369139 | 5206 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5207 | if (!vmf->page) |
5208 | goto unlock; | |
5209 | ||
5210 | get_page(vmf->page); | |
11bac800 | 5211 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5212 | vmf->page->index = vmf->pgoff; |
5213 | ||
5214 | ret = 0; | |
5215 | unlock: | |
5216 | rcu_read_unlock(); | |
5217 | ||
5218 | return ret; | |
5219 | } | |
5220 | ||
10c6db11 PZ |
5221 | static void ring_buffer_attach(struct perf_event *event, |
5222 | struct ring_buffer *rb) | |
5223 | { | |
b69cf536 | 5224 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5225 | unsigned long flags; |
5226 | ||
b69cf536 PZ |
5227 | if (event->rb) { |
5228 | /* | |
5229 | * Should be impossible, we set this when removing | |
5230 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5231 | */ | |
5232 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5233 | |
b69cf536 | 5234 | old_rb = event->rb; |
b69cf536 PZ |
5235 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5236 | list_del_rcu(&event->rb_entry); | |
5237 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5238 | |
2f993cf0 ON |
5239 | event->rcu_batches = get_state_synchronize_rcu(); |
5240 | event->rcu_pending = 1; | |
b69cf536 | 5241 | } |
10c6db11 | 5242 | |
b69cf536 | 5243 | if (rb) { |
2f993cf0 ON |
5244 | if (event->rcu_pending) { |
5245 | cond_synchronize_rcu(event->rcu_batches); | |
5246 | event->rcu_pending = 0; | |
5247 | } | |
5248 | ||
b69cf536 PZ |
5249 | spin_lock_irqsave(&rb->event_lock, flags); |
5250 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5251 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5252 | } | |
5253 | ||
767ae086 AS |
5254 | /* |
5255 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5256 | * before swizzling the event::rb pointer; if it's getting | |
5257 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5258 | * restart. See the comment in __perf_pmu_output_stop(). | |
5259 | * | |
5260 | * Data will inevitably be lost when set_output is done in | |
5261 | * mid-air, but then again, whoever does it like this is | |
5262 | * not in for the data anyway. | |
5263 | */ | |
5264 | if (has_aux(event)) | |
5265 | perf_event_stop(event, 0); | |
5266 | ||
b69cf536 PZ |
5267 | rcu_assign_pointer(event->rb, rb); |
5268 | ||
5269 | if (old_rb) { | |
5270 | ring_buffer_put(old_rb); | |
5271 | /* | |
5272 | * Since we detached before setting the new rb, so that we | |
5273 | * could attach the new rb, we could have missed a wakeup. | |
5274 | * Provide it now. | |
5275 | */ | |
5276 | wake_up_all(&event->waitq); | |
5277 | } | |
10c6db11 PZ |
5278 | } |
5279 | ||
5280 | static void ring_buffer_wakeup(struct perf_event *event) | |
5281 | { | |
5282 | struct ring_buffer *rb; | |
5283 | ||
5284 | rcu_read_lock(); | |
5285 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5286 | if (rb) { |
5287 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5288 | wake_up_all(&event->waitq); | |
5289 | } | |
10c6db11 PZ |
5290 | rcu_read_unlock(); |
5291 | } | |
5292 | ||
fdc26706 | 5293 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5294 | { |
76369139 | 5295 | struct ring_buffer *rb; |
7b732a75 | 5296 | |
ac9721f3 | 5297 | rcu_read_lock(); |
76369139 FW |
5298 | rb = rcu_dereference(event->rb); |
5299 | if (rb) { | |
5300 | if (!atomic_inc_not_zero(&rb->refcount)) | |
5301 | rb = NULL; | |
ac9721f3 PZ |
5302 | } |
5303 | rcu_read_unlock(); | |
5304 | ||
76369139 | 5305 | return rb; |
ac9721f3 PZ |
5306 | } |
5307 | ||
fdc26706 | 5308 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5309 | { |
76369139 | 5310 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 5311 | return; |
7b732a75 | 5312 | |
9bb5d40c | 5313 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5314 | |
76369139 | 5315 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5316 | } |
5317 | ||
5318 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5319 | { | |
cdd6c482 | 5320 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5321 | |
cdd6c482 | 5322 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5323 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5324 | |
45bfb2e5 PZ |
5325 | if (vma->vm_pgoff) |
5326 | atomic_inc(&event->rb->aux_mmap_count); | |
5327 | ||
1e0fb9ec | 5328 | if (event->pmu->event_mapped) |
bfe33492 | 5329 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5330 | } |
5331 | ||
95ff4ca2 AS |
5332 | static void perf_pmu_output_stop(struct perf_event *event); |
5333 | ||
9bb5d40c PZ |
5334 | /* |
5335 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5336 | * event, or through other events by use of perf_event_set_output(). | |
5337 | * | |
5338 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5339 | * the buffer here, where we still have a VM context. This means we need | |
5340 | * to detach all events redirecting to us. | |
5341 | */ | |
7b732a75 PZ |
5342 | static void perf_mmap_close(struct vm_area_struct *vma) |
5343 | { | |
cdd6c482 | 5344 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5345 | |
b69cf536 | 5346 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5347 | struct user_struct *mmap_user = rb->mmap_user; |
5348 | int mmap_locked = rb->mmap_locked; | |
5349 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5350 | |
1e0fb9ec | 5351 | if (event->pmu->event_unmapped) |
bfe33492 | 5352 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5353 | |
45bfb2e5 PZ |
5354 | /* |
5355 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5356 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5357 | * serialize with perf_mmap here. | |
5358 | */ | |
5359 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5360 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5361 | /* |
5362 | * Stop all AUX events that are writing to this buffer, | |
5363 | * so that we can free its AUX pages and corresponding PMU | |
5364 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5365 | * they won't start any more (see perf_aux_output_begin()). | |
5366 | */ | |
5367 | perf_pmu_output_stop(event); | |
5368 | ||
5369 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5370 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5371 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5372 | ||
95ff4ca2 | 5373 | /* this has to be the last one */ |
45bfb2e5 | 5374 | rb_free_aux(rb); |
95ff4ca2 AS |
5375 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5376 | ||
45bfb2e5 PZ |
5377 | mutex_unlock(&event->mmap_mutex); |
5378 | } | |
5379 | ||
9bb5d40c PZ |
5380 | atomic_dec(&rb->mmap_count); |
5381 | ||
5382 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5383 | goto out_put; |
9bb5d40c | 5384 | |
b69cf536 | 5385 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5386 | mutex_unlock(&event->mmap_mutex); |
5387 | ||
5388 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5389 | if (atomic_read(&rb->mmap_count)) |
5390 | goto out_put; | |
ac9721f3 | 5391 | |
9bb5d40c PZ |
5392 | /* |
5393 | * No other mmap()s, detach from all other events that might redirect | |
5394 | * into the now unreachable buffer. Somewhat complicated by the | |
5395 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5396 | */ | |
5397 | again: | |
5398 | rcu_read_lock(); | |
5399 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5400 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5401 | /* | |
5402 | * This event is en-route to free_event() which will | |
5403 | * detach it and remove it from the list. | |
5404 | */ | |
5405 | continue; | |
5406 | } | |
5407 | rcu_read_unlock(); | |
789f90fc | 5408 | |
9bb5d40c PZ |
5409 | mutex_lock(&event->mmap_mutex); |
5410 | /* | |
5411 | * Check we didn't race with perf_event_set_output() which can | |
5412 | * swizzle the rb from under us while we were waiting to | |
5413 | * acquire mmap_mutex. | |
5414 | * | |
5415 | * If we find a different rb; ignore this event, a next | |
5416 | * iteration will no longer find it on the list. We have to | |
5417 | * still restart the iteration to make sure we're not now | |
5418 | * iterating the wrong list. | |
5419 | */ | |
b69cf536 PZ |
5420 | if (event->rb == rb) |
5421 | ring_buffer_attach(event, NULL); | |
5422 | ||
cdd6c482 | 5423 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5424 | put_event(event); |
ac9721f3 | 5425 | |
9bb5d40c PZ |
5426 | /* |
5427 | * Restart the iteration; either we're on the wrong list or | |
5428 | * destroyed its integrity by doing a deletion. | |
5429 | */ | |
5430 | goto again; | |
7b732a75 | 5431 | } |
9bb5d40c PZ |
5432 | rcu_read_unlock(); |
5433 | ||
5434 | /* | |
5435 | * It could be there's still a few 0-ref events on the list; they'll | |
5436 | * get cleaned up by free_event() -- they'll also still have their | |
5437 | * ref on the rb and will free it whenever they are done with it. | |
5438 | * | |
5439 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5440 | * undo the VM accounting. | |
5441 | */ | |
5442 | ||
5443 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5444 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5445 | free_uid(mmap_user); | |
5446 | ||
b69cf536 | 5447 | out_put: |
9bb5d40c | 5448 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5449 | } |
5450 | ||
f0f37e2f | 5451 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5452 | .open = perf_mmap_open, |
45bfb2e5 | 5453 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5454 | .fault = perf_mmap_fault, |
5455 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5456 | }; |
5457 | ||
5458 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5459 | { | |
cdd6c482 | 5460 | struct perf_event *event = file->private_data; |
22a4f650 | 5461 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5462 | struct user_struct *user = current_user(); |
22a4f650 | 5463 | unsigned long locked, lock_limit; |
45bfb2e5 | 5464 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5465 | unsigned long vma_size; |
5466 | unsigned long nr_pages; | |
45bfb2e5 | 5467 | long user_extra = 0, extra = 0; |
d57e34fd | 5468 | int ret = 0, flags = 0; |
37d81828 | 5469 | |
c7920614 PZ |
5470 | /* |
5471 | * Don't allow mmap() of inherited per-task counters. This would | |
5472 | * create a performance issue due to all children writing to the | |
76369139 | 5473 | * same rb. |
c7920614 PZ |
5474 | */ |
5475 | if (event->cpu == -1 && event->attr.inherit) | |
5476 | return -EINVAL; | |
5477 | ||
43a21ea8 | 5478 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5479 | return -EINVAL; |
7b732a75 PZ |
5480 | |
5481 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5482 | |
5483 | if (vma->vm_pgoff == 0) { | |
5484 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5485 | } else { | |
5486 | /* | |
5487 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5488 | * mapped, all subsequent mappings should have the same size | |
5489 | * and offset. Must be above the normal perf buffer. | |
5490 | */ | |
5491 | u64 aux_offset, aux_size; | |
5492 | ||
5493 | if (!event->rb) | |
5494 | return -EINVAL; | |
5495 | ||
5496 | nr_pages = vma_size / PAGE_SIZE; | |
5497 | ||
5498 | mutex_lock(&event->mmap_mutex); | |
5499 | ret = -EINVAL; | |
5500 | ||
5501 | rb = event->rb; | |
5502 | if (!rb) | |
5503 | goto aux_unlock; | |
5504 | ||
6aa7de05 MR |
5505 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5506 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5507 | |
5508 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5509 | goto aux_unlock; | |
5510 | ||
5511 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5512 | goto aux_unlock; | |
5513 | ||
5514 | /* already mapped with a different offset */ | |
5515 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5516 | goto aux_unlock; | |
5517 | ||
5518 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5519 | goto aux_unlock; | |
5520 | ||
5521 | /* already mapped with a different size */ | |
5522 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5523 | goto aux_unlock; | |
5524 | ||
5525 | if (!is_power_of_2(nr_pages)) | |
5526 | goto aux_unlock; | |
5527 | ||
5528 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5529 | goto aux_unlock; | |
5530 | ||
5531 | if (rb_has_aux(rb)) { | |
5532 | atomic_inc(&rb->aux_mmap_count); | |
5533 | ret = 0; | |
5534 | goto unlock; | |
5535 | } | |
5536 | ||
5537 | atomic_set(&rb->aux_mmap_count, 1); | |
5538 | user_extra = nr_pages; | |
5539 | ||
5540 | goto accounting; | |
5541 | } | |
7b732a75 | 5542 | |
7730d865 | 5543 | /* |
76369139 | 5544 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5545 | * can do bitmasks instead of modulo. |
5546 | */ | |
2ed11312 | 5547 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5548 | return -EINVAL; |
5549 | ||
7b732a75 | 5550 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5551 | return -EINVAL; |
5552 | ||
cdd6c482 | 5553 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5554 | again: |
cdd6c482 | 5555 | mutex_lock(&event->mmap_mutex); |
76369139 | 5556 | if (event->rb) { |
9bb5d40c | 5557 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5558 | ret = -EINVAL; |
9bb5d40c PZ |
5559 | goto unlock; |
5560 | } | |
5561 | ||
5562 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5563 | /* | |
5564 | * Raced against perf_mmap_close() through | |
5565 | * perf_event_set_output(). Try again, hope for better | |
5566 | * luck. | |
5567 | */ | |
5568 | mutex_unlock(&event->mmap_mutex); | |
5569 | goto again; | |
5570 | } | |
5571 | ||
ebb3c4c4 PZ |
5572 | goto unlock; |
5573 | } | |
5574 | ||
789f90fc | 5575 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5576 | |
5577 | accounting: | |
cdd6c482 | 5578 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5579 | |
5580 | /* | |
5581 | * Increase the limit linearly with more CPUs: | |
5582 | */ | |
5583 | user_lock_limit *= num_online_cpus(); | |
5584 | ||
789f90fc | 5585 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5586 | |
789f90fc PZ |
5587 | if (user_locked > user_lock_limit) |
5588 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5589 | |
78d7d407 | 5590 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5591 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5592 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5593 | |
459ec28a IM |
5594 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5595 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5596 | ret = -EPERM; |
5597 | goto unlock; | |
5598 | } | |
7b732a75 | 5599 | |
45bfb2e5 | 5600 | WARN_ON(!rb && event->rb); |
906010b2 | 5601 | |
d57e34fd | 5602 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5603 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5604 | |
76369139 | 5605 | if (!rb) { |
45bfb2e5 PZ |
5606 | rb = rb_alloc(nr_pages, |
5607 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5608 | event->cpu, flags); | |
26cb63ad | 5609 | |
45bfb2e5 PZ |
5610 | if (!rb) { |
5611 | ret = -ENOMEM; | |
5612 | goto unlock; | |
5613 | } | |
43a21ea8 | 5614 | |
45bfb2e5 PZ |
5615 | atomic_set(&rb->mmap_count, 1); |
5616 | rb->mmap_user = get_current_user(); | |
5617 | rb->mmap_locked = extra; | |
26cb63ad | 5618 | |
45bfb2e5 | 5619 | ring_buffer_attach(event, rb); |
ac9721f3 | 5620 | |
45bfb2e5 PZ |
5621 | perf_event_init_userpage(event); |
5622 | perf_event_update_userpage(event); | |
5623 | } else { | |
1a594131 AS |
5624 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5625 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5626 | if (!ret) |
5627 | rb->aux_mmap_locked = extra; | |
5628 | } | |
9a0f05cb | 5629 | |
ebb3c4c4 | 5630 | unlock: |
45bfb2e5 PZ |
5631 | if (!ret) { |
5632 | atomic_long_add(user_extra, &user->locked_vm); | |
5633 | vma->vm_mm->pinned_vm += extra; | |
5634 | ||
ac9721f3 | 5635 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5636 | } else if (rb) { |
5637 | atomic_dec(&rb->mmap_count); | |
5638 | } | |
5639 | aux_unlock: | |
cdd6c482 | 5640 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5641 | |
9bb5d40c PZ |
5642 | /* |
5643 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5644 | * vma. | |
5645 | */ | |
26cb63ad | 5646 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5647 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5648 | |
1e0fb9ec | 5649 | if (event->pmu->event_mapped) |
bfe33492 | 5650 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5651 | |
7b732a75 | 5652 | return ret; |
37d81828 PM |
5653 | } |
5654 | ||
3c446b3d PZ |
5655 | static int perf_fasync(int fd, struct file *filp, int on) |
5656 | { | |
496ad9aa | 5657 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5658 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5659 | int retval; |
5660 | ||
5955102c | 5661 | inode_lock(inode); |
cdd6c482 | 5662 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5663 | inode_unlock(inode); |
3c446b3d PZ |
5664 | |
5665 | if (retval < 0) | |
5666 | return retval; | |
5667 | ||
5668 | return 0; | |
5669 | } | |
5670 | ||
0793a61d | 5671 | static const struct file_operations perf_fops = { |
3326c1ce | 5672 | .llseek = no_llseek, |
0793a61d TG |
5673 | .release = perf_release, |
5674 | .read = perf_read, | |
5675 | .poll = perf_poll, | |
d859e29f | 5676 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5677 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5678 | .mmap = perf_mmap, |
3c446b3d | 5679 | .fasync = perf_fasync, |
0793a61d TG |
5680 | }; |
5681 | ||
925d519a | 5682 | /* |
cdd6c482 | 5683 | * Perf event wakeup |
925d519a PZ |
5684 | * |
5685 | * If there's data, ensure we set the poll() state and publish everything | |
5686 | * to user-space before waking everybody up. | |
5687 | */ | |
5688 | ||
fed66e2c PZ |
5689 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5690 | { | |
5691 | /* only the parent has fasync state */ | |
5692 | if (event->parent) | |
5693 | event = event->parent; | |
5694 | return &event->fasync; | |
5695 | } | |
5696 | ||
cdd6c482 | 5697 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5698 | { |
10c6db11 | 5699 | ring_buffer_wakeup(event); |
4c9e2542 | 5700 | |
cdd6c482 | 5701 | if (event->pending_kill) { |
fed66e2c | 5702 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5703 | event->pending_kill = 0; |
4c9e2542 | 5704 | } |
925d519a PZ |
5705 | } |
5706 | ||
e360adbe | 5707 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5708 | { |
cdd6c482 IM |
5709 | struct perf_event *event = container_of(entry, |
5710 | struct perf_event, pending); | |
d525211f PZ |
5711 | int rctx; |
5712 | ||
5713 | rctx = perf_swevent_get_recursion_context(); | |
5714 | /* | |
5715 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5716 | * and we won't recurse 'further'. | |
5717 | */ | |
79f14641 | 5718 | |
cdd6c482 IM |
5719 | if (event->pending_disable) { |
5720 | event->pending_disable = 0; | |
fae3fde6 | 5721 | perf_event_disable_local(event); |
79f14641 PZ |
5722 | } |
5723 | ||
cdd6c482 IM |
5724 | if (event->pending_wakeup) { |
5725 | event->pending_wakeup = 0; | |
5726 | perf_event_wakeup(event); | |
79f14641 | 5727 | } |
d525211f PZ |
5728 | |
5729 | if (rctx >= 0) | |
5730 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5731 | } |
5732 | ||
39447b38 ZY |
5733 | /* |
5734 | * We assume there is only KVM supporting the callbacks. | |
5735 | * Later on, we might change it to a list if there is | |
5736 | * another virtualization implementation supporting the callbacks. | |
5737 | */ | |
5738 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5739 | ||
5740 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5741 | { | |
5742 | perf_guest_cbs = cbs; | |
5743 | return 0; | |
5744 | } | |
5745 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5746 | ||
5747 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5748 | { | |
5749 | perf_guest_cbs = NULL; | |
5750 | return 0; | |
5751 | } | |
5752 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5753 | ||
4018994f JO |
5754 | static void |
5755 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5756 | struct pt_regs *regs, u64 mask) | |
5757 | { | |
5758 | int bit; | |
29dd3288 | 5759 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5760 | |
29dd3288 MS |
5761 | bitmap_from_u64(_mask, mask); |
5762 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5763 | u64 val; |
5764 | ||
5765 | val = perf_reg_value(regs, bit); | |
5766 | perf_output_put(handle, val); | |
5767 | } | |
5768 | } | |
5769 | ||
60e2364e | 5770 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5771 | struct pt_regs *regs, |
5772 | struct pt_regs *regs_user_copy) | |
4018994f | 5773 | { |
88a7c26a AL |
5774 | if (user_mode(regs)) { |
5775 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5776 | regs_user->regs = regs; |
88a7c26a AL |
5777 | } else if (current->mm) { |
5778 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5779 | } else { |
5780 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5781 | regs_user->regs = NULL; | |
4018994f JO |
5782 | } |
5783 | } | |
5784 | ||
60e2364e SE |
5785 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5786 | struct pt_regs *regs) | |
5787 | { | |
5788 | regs_intr->regs = regs; | |
5789 | regs_intr->abi = perf_reg_abi(current); | |
5790 | } | |
5791 | ||
5792 | ||
c5ebcedb JO |
5793 | /* |
5794 | * Get remaining task size from user stack pointer. | |
5795 | * | |
5796 | * It'd be better to take stack vma map and limit this more | |
5797 | * precisly, but there's no way to get it safely under interrupt, | |
5798 | * so using TASK_SIZE as limit. | |
5799 | */ | |
5800 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5801 | { | |
5802 | unsigned long addr = perf_user_stack_pointer(regs); | |
5803 | ||
5804 | if (!addr || addr >= TASK_SIZE) | |
5805 | return 0; | |
5806 | ||
5807 | return TASK_SIZE - addr; | |
5808 | } | |
5809 | ||
5810 | static u16 | |
5811 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5812 | struct pt_regs *regs) | |
5813 | { | |
5814 | u64 task_size; | |
5815 | ||
5816 | /* No regs, no stack pointer, no dump. */ | |
5817 | if (!regs) | |
5818 | return 0; | |
5819 | ||
5820 | /* | |
5821 | * Check if we fit in with the requested stack size into the: | |
5822 | * - TASK_SIZE | |
5823 | * If we don't, we limit the size to the TASK_SIZE. | |
5824 | * | |
5825 | * - remaining sample size | |
5826 | * If we don't, we customize the stack size to | |
5827 | * fit in to the remaining sample size. | |
5828 | */ | |
5829 | ||
5830 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5831 | stack_size = min(stack_size, (u16) task_size); | |
5832 | ||
5833 | /* Current header size plus static size and dynamic size. */ | |
5834 | header_size += 2 * sizeof(u64); | |
5835 | ||
5836 | /* Do we fit in with the current stack dump size? */ | |
5837 | if ((u16) (header_size + stack_size) < header_size) { | |
5838 | /* | |
5839 | * If we overflow the maximum size for the sample, | |
5840 | * we customize the stack dump size to fit in. | |
5841 | */ | |
5842 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5843 | stack_size = round_up(stack_size, sizeof(u64)); | |
5844 | } | |
5845 | ||
5846 | return stack_size; | |
5847 | } | |
5848 | ||
5849 | static void | |
5850 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5851 | struct pt_regs *regs) | |
5852 | { | |
5853 | /* Case of a kernel thread, nothing to dump */ | |
5854 | if (!regs) { | |
5855 | u64 size = 0; | |
5856 | perf_output_put(handle, size); | |
5857 | } else { | |
5858 | unsigned long sp; | |
5859 | unsigned int rem; | |
5860 | u64 dyn_size; | |
5861 | ||
5862 | /* | |
5863 | * We dump: | |
5864 | * static size | |
5865 | * - the size requested by user or the best one we can fit | |
5866 | * in to the sample max size | |
5867 | * data | |
5868 | * - user stack dump data | |
5869 | * dynamic size | |
5870 | * - the actual dumped size | |
5871 | */ | |
5872 | ||
5873 | /* Static size. */ | |
5874 | perf_output_put(handle, dump_size); | |
5875 | ||
5876 | /* Data. */ | |
5877 | sp = perf_user_stack_pointer(regs); | |
5878 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5879 | dyn_size = dump_size - rem; | |
5880 | ||
5881 | perf_output_skip(handle, rem); | |
5882 | ||
5883 | /* Dynamic size. */ | |
5884 | perf_output_put(handle, dyn_size); | |
5885 | } | |
5886 | } | |
5887 | ||
c980d109 ACM |
5888 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5889 | struct perf_sample_data *data, | |
5890 | struct perf_event *event) | |
6844c09d ACM |
5891 | { |
5892 | u64 sample_type = event->attr.sample_type; | |
5893 | ||
5894 | data->type = sample_type; | |
5895 | header->size += event->id_header_size; | |
5896 | ||
5897 | if (sample_type & PERF_SAMPLE_TID) { | |
5898 | /* namespace issues */ | |
5899 | data->tid_entry.pid = perf_event_pid(event, current); | |
5900 | data->tid_entry.tid = perf_event_tid(event, current); | |
5901 | } | |
5902 | ||
5903 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5904 | data->time = perf_event_clock(event); |
6844c09d | 5905 | |
ff3d527c | 5906 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5907 | data->id = primary_event_id(event); |
5908 | ||
5909 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5910 | data->stream_id = event->id; | |
5911 | ||
5912 | if (sample_type & PERF_SAMPLE_CPU) { | |
5913 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5914 | data->cpu_entry.reserved = 0; | |
5915 | } | |
5916 | } | |
5917 | ||
76369139 FW |
5918 | void perf_event_header__init_id(struct perf_event_header *header, |
5919 | struct perf_sample_data *data, | |
5920 | struct perf_event *event) | |
c980d109 ACM |
5921 | { |
5922 | if (event->attr.sample_id_all) | |
5923 | __perf_event_header__init_id(header, data, event); | |
5924 | } | |
5925 | ||
5926 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5927 | struct perf_sample_data *data) | |
5928 | { | |
5929 | u64 sample_type = data->type; | |
5930 | ||
5931 | if (sample_type & PERF_SAMPLE_TID) | |
5932 | perf_output_put(handle, data->tid_entry); | |
5933 | ||
5934 | if (sample_type & PERF_SAMPLE_TIME) | |
5935 | perf_output_put(handle, data->time); | |
5936 | ||
5937 | if (sample_type & PERF_SAMPLE_ID) | |
5938 | perf_output_put(handle, data->id); | |
5939 | ||
5940 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5941 | perf_output_put(handle, data->stream_id); | |
5942 | ||
5943 | if (sample_type & PERF_SAMPLE_CPU) | |
5944 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5945 | |
5946 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5947 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5948 | } |
5949 | ||
76369139 FW |
5950 | void perf_event__output_id_sample(struct perf_event *event, |
5951 | struct perf_output_handle *handle, | |
5952 | struct perf_sample_data *sample) | |
c980d109 ACM |
5953 | { |
5954 | if (event->attr.sample_id_all) | |
5955 | __perf_event__output_id_sample(handle, sample); | |
5956 | } | |
5957 | ||
3dab77fb | 5958 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5959 | struct perf_event *event, |
5960 | u64 enabled, u64 running) | |
3dab77fb | 5961 | { |
cdd6c482 | 5962 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5963 | u64 values[4]; |
5964 | int n = 0; | |
5965 | ||
b5e58793 | 5966 | values[n++] = perf_event_count(event); |
3dab77fb | 5967 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5968 | values[n++] = enabled + |
cdd6c482 | 5969 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5970 | } |
5971 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5972 | values[n++] = running + |
cdd6c482 | 5973 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5974 | } |
5975 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5976 | values[n++] = primary_event_id(event); |
3dab77fb | 5977 | |
76369139 | 5978 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5979 | } |
5980 | ||
3dab77fb | 5981 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
5982 | struct perf_event *event, |
5983 | u64 enabled, u64 running) | |
3dab77fb | 5984 | { |
cdd6c482 IM |
5985 | struct perf_event *leader = event->group_leader, *sub; |
5986 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5987 | u64 values[5]; |
5988 | int n = 0; | |
5989 | ||
5990 | values[n++] = 1 + leader->nr_siblings; | |
5991 | ||
5992 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5993 | values[n++] = enabled; |
3dab77fb PZ |
5994 | |
5995 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5996 | values[n++] = running; |
3dab77fb | 5997 | |
9e5b127d PZ |
5998 | if ((leader != event) && |
5999 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6000 | leader->pmu->read(leader); |
6001 | ||
b5e58793 | 6002 | values[n++] = perf_event_count(leader); |
3dab77fb | 6003 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6004 | values[n++] = primary_event_id(leader); |
3dab77fb | 6005 | |
76369139 | 6006 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6007 | |
8343aae6 | 6008 | list_for_each_entry(sub, &leader->sibling_list, sibling_list) { |
3dab77fb PZ |
6009 | n = 0; |
6010 | ||
6f5ab001 JO |
6011 | if ((sub != event) && |
6012 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6013 | sub->pmu->read(sub); |
6014 | ||
b5e58793 | 6015 | values[n++] = perf_event_count(sub); |
3dab77fb | 6016 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6017 | values[n++] = primary_event_id(sub); |
3dab77fb | 6018 | |
76369139 | 6019 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6020 | } |
6021 | } | |
6022 | ||
eed01528 SE |
6023 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6024 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6025 | ||
ba5213ae PZ |
6026 | /* |
6027 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6028 | * | |
6029 | * The problem is that its both hard and excessively expensive to iterate the | |
6030 | * child list, not to mention that its impossible to IPI the children running | |
6031 | * on another CPU, from interrupt/NMI context. | |
6032 | */ | |
3dab77fb | 6033 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6034 | struct perf_event *event) |
3dab77fb | 6035 | { |
e3f3541c | 6036 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6037 | u64 read_format = event->attr.read_format; |
6038 | ||
6039 | /* | |
6040 | * compute total_time_enabled, total_time_running | |
6041 | * based on snapshot values taken when the event | |
6042 | * was last scheduled in. | |
6043 | * | |
6044 | * we cannot simply called update_context_time() | |
6045 | * because of locking issue as we are called in | |
6046 | * NMI context | |
6047 | */ | |
c4794295 | 6048 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6049 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6050 | |
cdd6c482 | 6051 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6052 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6053 | else |
eed01528 | 6054 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6055 | } |
6056 | ||
5622f295 MM |
6057 | void perf_output_sample(struct perf_output_handle *handle, |
6058 | struct perf_event_header *header, | |
6059 | struct perf_sample_data *data, | |
cdd6c482 | 6060 | struct perf_event *event) |
5622f295 MM |
6061 | { |
6062 | u64 sample_type = data->type; | |
6063 | ||
6064 | perf_output_put(handle, *header); | |
6065 | ||
ff3d527c AH |
6066 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6067 | perf_output_put(handle, data->id); | |
6068 | ||
5622f295 MM |
6069 | if (sample_type & PERF_SAMPLE_IP) |
6070 | perf_output_put(handle, data->ip); | |
6071 | ||
6072 | if (sample_type & PERF_SAMPLE_TID) | |
6073 | perf_output_put(handle, data->tid_entry); | |
6074 | ||
6075 | if (sample_type & PERF_SAMPLE_TIME) | |
6076 | perf_output_put(handle, data->time); | |
6077 | ||
6078 | if (sample_type & PERF_SAMPLE_ADDR) | |
6079 | perf_output_put(handle, data->addr); | |
6080 | ||
6081 | if (sample_type & PERF_SAMPLE_ID) | |
6082 | perf_output_put(handle, data->id); | |
6083 | ||
6084 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6085 | perf_output_put(handle, data->stream_id); | |
6086 | ||
6087 | if (sample_type & PERF_SAMPLE_CPU) | |
6088 | perf_output_put(handle, data->cpu_entry); | |
6089 | ||
6090 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6091 | perf_output_put(handle, data->period); | |
6092 | ||
6093 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6094 | perf_output_read(handle, event); |
5622f295 MM |
6095 | |
6096 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6097 | int size = 1; |
5622f295 | 6098 | |
99e818cc JO |
6099 | size += data->callchain->nr; |
6100 | size *= sizeof(u64); | |
6101 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6102 | } |
6103 | ||
6104 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6105 | struct perf_raw_record *raw = data->raw; |
6106 | ||
6107 | if (raw) { | |
6108 | struct perf_raw_frag *frag = &raw->frag; | |
6109 | ||
6110 | perf_output_put(handle, raw->size); | |
6111 | do { | |
6112 | if (frag->copy) { | |
6113 | __output_custom(handle, frag->copy, | |
6114 | frag->data, frag->size); | |
6115 | } else { | |
6116 | __output_copy(handle, frag->data, | |
6117 | frag->size); | |
6118 | } | |
6119 | if (perf_raw_frag_last(frag)) | |
6120 | break; | |
6121 | frag = frag->next; | |
6122 | } while (1); | |
6123 | if (frag->pad) | |
6124 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6125 | } else { |
6126 | struct { | |
6127 | u32 size; | |
6128 | u32 data; | |
6129 | } raw = { | |
6130 | .size = sizeof(u32), | |
6131 | .data = 0, | |
6132 | }; | |
6133 | perf_output_put(handle, raw); | |
6134 | } | |
6135 | } | |
a7ac67ea | 6136 | |
bce38cd5 SE |
6137 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6138 | if (data->br_stack) { | |
6139 | size_t size; | |
6140 | ||
6141 | size = data->br_stack->nr | |
6142 | * sizeof(struct perf_branch_entry); | |
6143 | ||
6144 | perf_output_put(handle, data->br_stack->nr); | |
6145 | perf_output_copy(handle, data->br_stack->entries, size); | |
6146 | } else { | |
6147 | /* | |
6148 | * we always store at least the value of nr | |
6149 | */ | |
6150 | u64 nr = 0; | |
6151 | perf_output_put(handle, nr); | |
6152 | } | |
6153 | } | |
4018994f JO |
6154 | |
6155 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6156 | u64 abi = data->regs_user.abi; | |
6157 | ||
6158 | /* | |
6159 | * If there are no regs to dump, notice it through | |
6160 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6161 | */ | |
6162 | perf_output_put(handle, abi); | |
6163 | ||
6164 | if (abi) { | |
6165 | u64 mask = event->attr.sample_regs_user; | |
6166 | perf_output_sample_regs(handle, | |
6167 | data->regs_user.regs, | |
6168 | mask); | |
6169 | } | |
6170 | } | |
c5ebcedb | 6171 | |
a5cdd40c | 6172 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6173 | perf_output_sample_ustack(handle, |
6174 | data->stack_user_size, | |
6175 | data->regs_user.regs); | |
a5cdd40c | 6176 | } |
c3feedf2 AK |
6177 | |
6178 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6179 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6180 | |
6181 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6182 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6183 | |
fdfbbd07 AK |
6184 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6185 | perf_output_put(handle, data->txn); | |
6186 | ||
60e2364e SE |
6187 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6188 | u64 abi = data->regs_intr.abi; | |
6189 | /* | |
6190 | * If there are no regs to dump, notice it through | |
6191 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6192 | */ | |
6193 | perf_output_put(handle, abi); | |
6194 | ||
6195 | if (abi) { | |
6196 | u64 mask = event->attr.sample_regs_intr; | |
6197 | ||
6198 | perf_output_sample_regs(handle, | |
6199 | data->regs_intr.regs, | |
6200 | mask); | |
6201 | } | |
6202 | } | |
6203 | ||
fc7ce9c7 KL |
6204 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6205 | perf_output_put(handle, data->phys_addr); | |
6206 | ||
a5cdd40c PZ |
6207 | if (!event->attr.watermark) { |
6208 | int wakeup_events = event->attr.wakeup_events; | |
6209 | ||
6210 | if (wakeup_events) { | |
6211 | struct ring_buffer *rb = handle->rb; | |
6212 | int events = local_inc_return(&rb->events); | |
6213 | ||
6214 | if (events >= wakeup_events) { | |
6215 | local_sub(wakeup_events, &rb->events); | |
6216 | local_inc(&rb->wakeup); | |
6217 | } | |
6218 | } | |
6219 | } | |
5622f295 MM |
6220 | } |
6221 | ||
fc7ce9c7 KL |
6222 | static u64 perf_virt_to_phys(u64 virt) |
6223 | { | |
6224 | u64 phys_addr = 0; | |
6225 | struct page *p = NULL; | |
6226 | ||
6227 | if (!virt) | |
6228 | return 0; | |
6229 | ||
6230 | if (virt >= TASK_SIZE) { | |
6231 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6232 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6233 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6234 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6235 | } else { | |
6236 | /* | |
6237 | * Walking the pages tables for user address. | |
6238 | * Interrupts are disabled, so it prevents any tear down | |
6239 | * of the page tables. | |
6240 | * Try IRQ-safe __get_user_pages_fast first. | |
6241 | * If failed, leave phys_addr as 0. | |
6242 | */ | |
6243 | if ((current->mm != NULL) && | |
6244 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6245 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6246 | ||
6247 | if (p) | |
6248 | put_page(p); | |
6249 | } | |
6250 | ||
6251 | return phys_addr; | |
6252 | } | |
6253 | ||
99e818cc JO |
6254 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6255 | ||
8cf7e0e2 JO |
6256 | static struct perf_callchain_entry * |
6257 | perf_callchain(struct perf_event *event, struct pt_regs *regs) | |
6258 | { | |
6259 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6260 | bool user = !event->attr.exclude_callchain_user; | |
6261 | /* Disallow cross-task user callchains. */ | |
6262 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6263 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6264 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6265 | |
6266 | if (!kernel && !user) | |
99e818cc | 6267 | return &__empty_callchain; |
8cf7e0e2 | 6268 | |
99e818cc JO |
6269 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6270 | max_stack, crosstask, true); | |
6271 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6272 | } |
6273 | ||
5622f295 MM |
6274 | void perf_prepare_sample(struct perf_event_header *header, |
6275 | struct perf_sample_data *data, | |
cdd6c482 | 6276 | struct perf_event *event, |
5622f295 | 6277 | struct pt_regs *regs) |
7b732a75 | 6278 | { |
cdd6c482 | 6279 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6280 | |
cdd6c482 | 6281 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6282 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6283 | |
6284 | header->misc = 0; | |
6285 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6286 | |
c980d109 | 6287 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6288 | |
c320c7b7 | 6289 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6290 | data->ip = perf_instruction_pointer(regs); |
6291 | ||
b23f3325 | 6292 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6293 | int size = 1; |
394ee076 | 6294 | |
e6dab5ff | 6295 | data->callchain = perf_callchain(event, regs); |
99e818cc | 6296 | size += data->callchain->nr; |
5622f295 MM |
6297 | |
6298 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6299 | } |
6300 | ||
3a43ce68 | 6301 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6302 | struct perf_raw_record *raw = data->raw; |
6303 | int size; | |
6304 | ||
6305 | if (raw) { | |
6306 | struct perf_raw_frag *frag = &raw->frag; | |
6307 | u32 sum = 0; | |
6308 | ||
6309 | do { | |
6310 | sum += frag->size; | |
6311 | if (perf_raw_frag_last(frag)) | |
6312 | break; | |
6313 | frag = frag->next; | |
6314 | } while (1); | |
6315 | ||
6316 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6317 | raw->size = size - sizeof(u32); | |
6318 | frag->pad = raw->size - sum; | |
6319 | } else { | |
6320 | size = sizeof(u64); | |
6321 | } | |
a044560c | 6322 | |
7e3f977e | 6323 | header->size += size; |
7f453c24 | 6324 | } |
bce38cd5 SE |
6325 | |
6326 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6327 | int size = sizeof(u64); /* nr */ | |
6328 | if (data->br_stack) { | |
6329 | size += data->br_stack->nr | |
6330 | * sizeof(struct perf_branch_entry); | |
6331 | } | |
6332 | header->size += size; | |
6333 | } | |
4018994f | 6334 | |
2565711f | 6335 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6336 | perf_sample_regs_user(&data->regs_user, regs, |
6337 | &data->regs_user_copy); | |
2565711f | 6338 | |
4018994f JO |
6339 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6340 | /* regs dump ABI info */ | |
6341 | int size = sizeof(u64); | |
6342 | ||
4018994f JO |
6343 | if (data->regs_user.regs) { |
6344 | u64 mask = event->attr.sample_regs_user; | |
6345 | size += hweight64(mask) * sizeof(u64); | |
6346 | } | |
6347 | ||
6348 | header->size += size; | |
6349 | } | |
c5ebcedb JO |
6350 | |
6351 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6352 | /* | |
6353 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6354 | * processed as the last one or have additional check added | |
6355 | * in case new sample type is added, because we could eat | |
6356 | * up the rest of the sample size. | |
6357 | */ | |
c5ebcedb JO |
6358 | u16 stack_size = event->attr.sample_stack_user; |
6359 | u16 size = sizeof(u64); | |
6360 | ||
c5ebcedb | 6361 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6362 | data->regs_user.regs); |
c5ebcedb JO |
6363 | |
6364 | /* | |
6365 | * If there is something to dump, add space for the dump | |
6366 | * itself and for the field that tells the dynamic size, | |
6367 | * which is how many have been actually dumped. | |
6368 | */ | |
6369 | if (stack_size) | |
6370 | size += sizeof(u64) + stack_size; | |
6371 | ||
6372 | data->stack_user_size = stack_size; | |
6373 | header->size += size; | |
6374 | } | |
60e2364e SE |
6375 | |
6376 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6377 | /* regs dump ABI info */ | |
6378 | int size = sizeof(u64); | |
6379 | ||
6380 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6381 | ||
6382 | if (data->regs_intr.regs) { | |
6383 | u64 mask = event->attr.sample_regs_intr; | |
6384 | ||
6385 | size += hweight64(mask) * sizeof(u64); | |
6386 | } | |
6387 | ||
6388 | header->size += size; | |
6389 | } | |
fc7ce9c7 KL |
6390 | |
6391 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6392 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6393 | } |
7f453c24 | 6394 | |
9ecda41a WN |
6395 | static void __always_inline |
6396 | __perf_event_output(struct perf_event *event, | |
6397 | struct perf_sample_data *data, | |
6398 | struct pt_regs *regs, | |
6399 | int (*output_begin)(struct perf_output_handle *, | |
6400 | struct perf_event *, | |
6401 | unsigned int)) | |
5622f295 MM |
6402 | { |
6403 | struct perf_output_handle handle; | |
6404 | struct perf_event_header header; | |
689802b2 | 6405 | |
927c7a9e FW |
6406 | /* protect the callchain buffers */ |
6407 | rcu_read_lock(); | |
6408 | ||
cdd6c482 | 6409 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6410 | |
9ecda41a | 6411 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6412 | goto exit; |
0322cd6e | 6413 | |
cdd6c482 | 6414 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6415 | |
8a057d84 | 6416 | perf_output_end(&handle); |
927c7a9e FW |
6417 | |
6418 | exit: | |
6419 | rcu_read_unlock(); | |
0322cd6e PZ |
6420 | } |
6421 | ||
9ecda41a WN |
6422 | void |
6423 | perf_event_output_forward(struct perf_event *event, | |
6424 | struct perf_sample_data *data, | |
6425 | struct pt_regs *regs) | |
6426 | { | |
6427 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6428 | } | |
6429 | ||
6430 | void | |
6431 | perf_event_output_backward(struct perf_event *event, | |
6432 | struct perf_sample_data *data, | |
6433 | struct pt_regs *regs) | |
6434 | { | |
6435 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6436 | } | |
6437 | ||
6438 | void | |
6439 | perf_event_output(struct perf_event *event, | |
6440 | struct perf_sample_data *data, | |
6441 | struct pt_regs *regs) | |
6442 | { | |
6443 | __perf_event_output(event, data, regs, perf_output_begin); | |
6444 | } | |
6445 | ||
38b200d6 | 6446 | /* |
cdd6c482 | 6447 | * read event_id |
38b200d6 PZ |
6448 | */ |
6449 | ||
6450 | struct perf_read_event { | |
6451 | struct perf_event_header header; | |
6452 | ||
6453 | u32 pid; | |
6454 | u32 tid; | |
38b200d6 PZ |
6455 | }; |
6456 | ||
6457 | static void | |
cdd6c482 | 6458 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6459 | struct task_struct *task) |
6460 | { | |
6461 | struct perf_output_handle handle; | |
c980d109 | 6462 | struct perf_sample_data sample; |
dfc65094 | 6463 | struct perf_read_event read_event = { |
38b200d6 | 6464 | .header = { |
cdd6c482 | 6465 | .type = PERF_RECORD_READ, |
38b200d6 | 6466 | .misc = 0, |
c320c7b7 | 6467 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6468 | }, |
cdd6c482 IM |
6469 | .pid = perf_event_pid(event, task), |
6470 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6471 | }; |
3dab77fb | 6472 | int ret; |
38b200d6 | 6473 | |
c980d109 | 6474 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6475 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6476 | if (ret) |
6477 | return; | |
6478 | ||
dfc65094 | 6479 | perf_output_put(&handle, read_event); |
cdd6c482 | 6480 | perf_output_read(&handle, event); |
c980d109 | 6481 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6482 | |
38b200d6 PZ |
6483 | perf_output_end(&handle); |
6484 | } | |
6485 | ||
aab5b71e | 6486 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6487 | |
6488 | static void | |
aab5b71e PZ |
6489 | perf_iterate_ctx(struct perf_event_context *ctx, |
6490 | perf_iterate_f output, | |
b73e4fef | 6491 | void *data, bool all) |
52d857a8 JO |
6492 | { |
6493 | struct perf_event *event; | |
6494 | ||
6495 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6496 | if (!all) { |
6497 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6498 | continue; | |
6499 | if (!event_filter_match(event)) | |
6500 | continue; | |
6501 | } | |
6502 | ||
67516844 | 6503 | output(event, data); |
52d857a8 JO |
6504 | } |
6505 | } | |
6506 | ||
aab5b71e | 6507 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6508 | { |
6509 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6510 | struct perf_event *event; | |
6511 | ||
6512 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6513 | /* |
6514 | * Skip events that are not fully formed yet; ensure that | |
6515 | * if we observe event->ctx, both event and ctx will be | |
6516 | * complete enough. See perf_install_in_context(). | |
6517 | */ | |
6518 | if (!smp_load_acquire(&event->ctx)) | |
6519 | continue; | |
6520 | ||
f2fb6bef KL |
6521 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6522 | continue; | |
6523 | if (!event_filter_match(event)) | |
6524 | continue; | |
6525 | output(event, data); | |
6526 | } | |
6527 | } | |
6528 | ||
aab5b71e PZ |
6529 | /* |
6530 | * Iterate all events that need to receive side-band events. | |
6531 | * | |
6532 | * For new callers; ensure that account_pmu_sb_event() includes | |
6533 | * your event, otherwise it might not get delivered. | |
6534 | */ | |
52d857a8 | 6535 | static void |
aab5b71e | 6536 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6537 | struct perf_event_context *task_ctx) |
6538 | { | |
52d857a8 | 6539 | struct perf_event_context *ctx; |
52d857a8 JO |
6540 | int ctxn; |
6541 | ||
aab5b71e PZ |
6542 | rcu_read_lock(); |
6543 | preempt_disable(); | |
6544 | ||
4e93ad60 | 6545 | /* |
aab5b71e PZ |
6546 | * If we have task_ctx != NULL we only notify the task context itself. |
6547 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6548 | * context. |
6549 | */ | |
6550 | if (task_ctx) { | |
aab5b71e PZ |
6551 | perf_iterate_ctx(task_ctx, output, data, false); |
6552 | goto done; | |
4e93ad60 JO |
6553 | } |
6554 | ||
aab5b71e | 6555 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6556 | |
6557 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6558 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6559 | if (ctx) | |
aab5b71e | 6560 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6561 | } |
aab5b71e | 6562 | done: |
f2fb6bef | 6563 | preempt_enable(); |
52d857a8 | 6564 | rcu_read_unlock(); |
95ff4ca2 AS |
6565 | } |
6566 | ||
375637bc AS |
6567 | /* |
6568 | * Clear all file-based filters at exec, they'll have to be | |
6569 | * re-instated when/if these objects are mmapped again. | |
6570 | */ | |
6571 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6572 | { | |
6573 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6574 | struct perf_addr_filter *filter; | |
6575 | unsigned int restart = 0, count = 0; | |
6576 | unsigned long flags; | |
6577 | ||
6578 | if (!has_addr_filter(event)) | |
6579 | return; | |
6580 | ||
6581 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6582 | list_for_each_entry(filter, &ifh->list, entry) { | |
6583 | if (filter->inode) { | |
6584 | event->addr_filters_offs[count] = 0; | |
6585 | restart++; | |
6586 | } | |
6587 | ||
6588 | count++; | |
6589 | } | |
6590 | ||
6591 | if (restart) | |
6592 | event->addr_filters_gen++; | |
6593 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6594 | ||
6595 | if (restart) | |
767ae086 | 6596 | perf_event_stop(event, 1); |
375637bc AS |
6597 | } |
6598 | ||
6599 | void perf_event_exec(void) | |
6600 | { | |
6601 | struct perf_event_context *ctx; | |
6602 | int ctxn; | |
6603 | ||
6604 | rcu_read_lock(); | |
6605 | for_each_task_context_nr(ctxn) { | |
6606 | ctx = current->perf_event_ctxp[ctxn]; | |
6607 | if (!ctx) | |
6608 | continue; | |
6609 | ||
6610 | perf_event_enable_on_exec(ctxn); | |
6611 | ||
aab5b71e | 6612 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6613 | true); |
6614 | } | |
6615 | rcu_read_unlock(); | |
6616 | } | |
6617 | ||
95ff4ca2 AS |
6618 | struct remote_output { |
6619 | struct ring_buffer *rb; | |
6620 | int err; | |
6621 | }; | |
6622 | ||
6623 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6624 | { | |
6625 | struct perf_event *parent = event->parent; | |
6626 | struct remote_output *ro = data; | |
6627 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6628 | struct stop_event_data sd = { |
6629 | .event = event, | |
6630 | }; | |
95ff4ca2 AS |
6631 | |
6632 | if (!has_aux(event)) | |
6633 | return; | |
6634 | ||
6635 | if (!parent) | |
6636 | parent = event; | |
6637 | ||
6638 | /* | |
6639 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6640 | * ring-buffer, but it will be the child that's actually using it. |
6641 | * | |
6642 | * We are using event::rb to determine if the event should be stopped, | |
6643 | * however this may race with ring_buffer_attach() (through set_output), | |
6644 | * which will make us skip the event that actually needs to be stopped. | |
6645 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6646 | * its rb pointer. | |
95ff4ca2 AS |
6647 | */ |
6648 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6649 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6650 | } |
6651 | ||
6652 | static int __perf_pmu_output_stop(void *info) | |
6653 | { | |
6654 | struct perf_event *event = info; | |
6655 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6656 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6657 | struct remote_output ro = { |
6658 | .rb = event->rb, | |
6659 | }; | |
6660 | ||
6661 | rcu_read_lock(); | |
aab5b71e | 6662 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6663 | if (cpuctx->task_ctx) |
aab5b71e | 6664 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6665 | &ro, false); |
95ff4ca2 AS |
6666 | rcu_read_unlock(); |
6667 | ||
6668 | return ro.err; | |
6669 | } | |
6670 | ||
6671 | static void perf_pmu_output_stop(struct perf_event *event) | |
6672 | { | |
6673 | struct perf_event *iter; | |
6674 | int err, cpu; | |
6675 | ||
6676 | restart: | |
6677 | rcu_read_lock(); | |
6678 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6679 | /* | |
6680 | * For per-CPU events, we need to make sure that neither they | |
6681 | * nor their children are running; for cpu==-1 events it's | |
6682 | * sufficient to stop the event itself if it's active, since | |
6683 | * it can't have children. | |
6684 | */ | |
6685 | cpu = iter->cpu; | |
6686 | if (cpu == -1) | |
6687 | cpu = READ_ONCE(iter->oncpu); | |
6688 | ||
6689 | if (cpu == -1) | |
6690 | continue; | |
6691 | ||
6692 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6693 | if (err == -EAGAIN) { | |
6694 | rcu_read_unlock(); | |
6695 | goto restart; | |
6696 | } | |
6697 | } | |
6698 | rcu_read_unlock(); | |
52d857a8 JO |
6699 | } |
6700 | ||
60313ebe | 6701 | /* |
9f498cc5 PZ |
6702 | * task tracking -- fork/exit |
6703 | * | |
13d7a241 | 6704 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6705 | */ |
6706 | ||
9f498cc5 | 6707 | struct perf_task_event { |
3a80b4a3 | 6708 | struct task_struct *task; |
cdd6c482 | 6709 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6710 | |
6711 | struct { | |
6712 | struct perf_event_header header; | |
6713 | ||
6714 | u32 pid; | |
6715 | u32 ppid; | |
9f498cc5 PZ |
6716 | u32 tid; |
6717 | u32 ptid; | |
393b2ad8 | 6718 | u64 time; |
cdd6c482 | 6719 | } event_id; |
60313ebe PZ |
6720 | }; |
6721 | ||
67516844 JO |
6722 | static int perf_event_task_match(struct perf_event *event) |
6723 | { | |
13d7a241 SE |
6724 | return event->attr.comm || event->attr.mmap || |
6725 | event->attr.mmap2 || event->attr.mmap_data || | |
6726 | event->attr.task; | |
67516844 JO |
6727 | } |
6728 | ||
cdd6c482 | 6729 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6730 | void *data) |
60313ebe | 6731 | { |
52d857a8 | 6732 | struct perf_task_event *task_event = data; |
60313ebe | 6733 | struct perf_output_handle handle; |
c980d109 | 6734 | struct perf_sample_data sample; |
9f498cc5 | 6735 | struct task_struct *task = task_event->task; |
c980d109 | 6736 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6737 | |
67516844 JO |
6738 | if (!perf_event_task_match(event)) |
6739 | return; | |
6740 | ||
c980d109 | 6741 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6742 | |
c980d109 | 6743 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6744 | task_event->event_id.header.size); |
ef60777c | 6745 | if (ret) |
c980d109 | 6746 | goto out; |
60313ebe | 6747 | |
cdd6c482 IM |
6748 | task_event->event_id.pid = perf_event_pid(event, task); |
6749 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6750 | |
cdd6c482 IM |
6751 | task_event->event_id.tid = perf_event_tid(event, task); |
6752 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6753 | |
34f43927 PZ |
6754 | task_event->event_id.time = perf_event_clock(event); |
6755 | ||
cdd6c482 | 6756 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6757 | |
c980d109 ACM |
6758 | perf_event__output_id_sample(event, &handle, &sample); |
6759 | ||
60313ebe | 6760 | perf_output_end(&handle); |
c980d109 ACM |
6761 | out: |
6762 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6763 | } |
6764 | ||
cdd6c482 IM |
6765 | static void perf_event_task(struct task_struct *task, |
6766 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6767 | int new) |
60313ebe | 6768 | { |
9f498cc5 | 6769 | struct perf_task_event task_event; |
60313ebe | 6770 | |
cdd6c482 IM |
6771 | if (!atomic_read(&nr_comm_events) && |
6772 | !atomic_read(&nr_mmap_events) && | |
6773 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6774 | return; |
6775 | ||
9f498cc5 | 6776 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6777 | .task = task, |
6778 | .task_ctx = task_ctx, | |
cdd6c482 | 6779 | .event_id = { |
60313ebe | 6780 | .header = { |
cdd6c482 | 6781 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6782 | .misc = 0, |
cdd6c482 | 6783 | .size = sizeof(task_event.event_id), |
60313ebe | 6784 | }, |
573402db PZ |
6785 | /* .pid */ |
6786 | /* .ppid */ | |
9f498cc5 PZ |
6787 | /* .tid */ |
6788 | /* .ptid */ | |
34f43927 | 6789 | /* .time */ |
60313ebe PZ |
6790 | }, |
6791 | }; | |
6792 | ||
aab5b71e | 6793 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6794 | &task_event, |
6795 | task_ctx); | |
9f498cc5 PZ |
6796 | } |
6797 | ||
cdd6c482 | 6798 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6799 | { |
cdd6c482 | 6800 | perf_event_task(task, NULL, 1); |
e4222673 | 6801 | perf_event_namespaces(task); |
60313ebe PZ |
6802 | } |
6803 | ||
8d1b2d93 PZ |
6804 | /* |
6805 | * comm tracking | |
6806 | */ | |
6807 | ||
6808 | struct perf_comm_event { | |
22a4f650 IM |
6809 | struct task_struct *task; |
6810 | char *comm; | |
8d1b2d93 PZ |
6811 | int comm_size; |
6812 | ||
6813 | struct { | |
6814 | struct perf_event_header header; | |
6815 | ||
6816 | u32 pid; | |
6817 | u32 tid; | |
cdd6c482 | 6818 | } event_id; |
8d1b2d93 PZ |
6819 | }; |
6820 | ||
67516844 JO |
6821 | static int perf_event_comm_match(struct perf_event *event) |
6822 | { | |
6823 | return event->attr.comm; | |
6824 | } | |
6825 | ||
cdd6c482 | 6826 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6827 | void *data) |
8d1b2d93 | 6828 | { |
52d857a8 | 6829 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6830 | struct perf_output_handle handle; |
c980d109 | 6831 | struct perf_sample_data sample; |
cdd6c482 | 6832 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6833 | int ret; |
6834 | ||
67516844 JO |
6835 | if (!perf_event_comm_match(event)) |
6836 | return; | |
6837 | ||
c980d109 ACM |
6838 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6839 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6840 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6841 | |
6842 | if (ret) | |
c980d109 | 6843 | goto out; |
8d1b2d93 | 6844 | |
cdd6c482 IM |
6845 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6846 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6847 | |
cdd6c482 | 6848 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6849 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6850 | comm_event->comm_size); |
c980d109 ACM |
6851 | |
6852 | perf_event__output_id_sample(event, &handle, &sample); | |
6853 | ||
8d1b2d93 | 6854 | perf_output_end(&handle); |
c980d109 ACM |
6855 | out: |
6856 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6857 | } |
6858 | ||
cdd6c482 | 6859 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6860 | { |
413ee3b4 | 6861 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6862 | unsigned int size; |
8d1b2d93 | 6863 | |
413ee3b4 | 6864 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6865 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6866 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6867 | |
6868 | comm_event->comm = comm; | |
6869 | comm_event->comm_size = size; | |
6870 | ||
cdd6c482 | 6871 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6872 | |
aab5b71e | 6873 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6874 | comm_event, |
6875 | NULL); | |
8d1b2d93 PZ |
6876 | } |
6877 | ||
82b89778 | 6878 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6879 | { |
9ee318a7 PZ |
6880 | struct perf_comm_event comm_event; |
6881 | ||
cdd6c482 | 6882 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6883 | return; |
a63eaf34 | 6884 | |
9ee318a7 | 6885 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6886 | .task = task, |
573402db PZ |
6887 | /* .comm */ |
6888 | /* .comm_size */ | |
cdd6c482 | 6889 | .event_id = { |
573402db | 6890 | .header = { |
cdd6c482 | 6891 | .type = PERF_RECORD_COMM, |
82b89778 | 6892 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6893 | /* .size */ |
6894 | }, | |
6895 | /* .pid */ | |
6896 | /* .tid */ | |
8d1b2d93 PZ |
6897 | }, |
6898 | }; | |
6899 | ||
cdd6c482 | 6900 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6901 | } |
6902 | ||
e4222673 HB |
6903 | /* |
6904 | * namespaces tracking | |
6905 | */ | |
6906 | ||
6907 | struct perf_namespaces_event { | |
6908 | struct task_struct *task; | |
6909 | ||
6910 | struct { | |
6911 | struct perf_event_header header; | |
6912 | ||
6913 | u32 pid; | |
6914 | u32 tid; | |
6915 | u64 nr_namespaces; | |
6916 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
6917 | } event_id; | |
6918 | }; | |
6919 | ||
6920 | static int perf_event_namespaces_match(struct perf_event *event) | |
6921 | { | |
6922 | return event->attr.namespaces; | |
6923 | } | |
6924 | ||
6925 | static void perf_event_namespaces_output(struct perf_event *event, | |
6926 | void *data) | |
6927 | { | |
6928 | struct perf_namespaces_event *namespaces_event = data; | |
6929 | struct perf_output_handle handle; | |
6930 | struct perf_sample_data sample; | |
34900ec5 | 6931 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
6932 | int ret; |
6933 | ||
6934 | if (!perf_event_namespaces_match(event)) | |
6935 | return; | |
6936 | ||
6937 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
6938 | &sample, event); | |
6939 | ret = perf_output_begin(&handle, event, | |
6940 | namespaces_event->event_id.header.size); | |
6941 | if (ret) | |
34900ec5 | 6942 | goto out; |
e4222673 HB |
6943 | |
6944 | namespaces_event->event_id.pid = perf_event_pid(event, | |
6945 | namespaces_event->task); | |
6946 | namespaces_event->event_id.tid = perf_event_tid(event, | |
6947 | namespaces_event->task); | |
6948 | ||
6949 | perf_output_put(&handle, namespaces_event->event_id); | |
6950 | ||
6951 | perf_event__output_id_sample(event, &handle, &sample); | |
6952 | ||
6953 | perf_output_end(&handle); | |
34900ec5 JO |
6954 | out: |
6955 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
6956 | } |
6957 | ||
6958 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
6959 | struct task_struct *task, | |
6960 | const struct proc_ns_operations *ns_ops) | |
6961 | { | |
6962 | struct path ns_path; | |
6963 | struct inode *ns_inode; | |
6964 | void *error; | |
6965 | ||
6966 | error = ns_get_path(&ns_path, task, ns_ops); | |
6967 | if (!error) { | |
6968 | ns_inode = ns_path.dentry->d_inode; | |
6969 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
6970 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 6971 | path_put(&ns_path); |
e4222673 HB |
6972 | } |
6973 | } | |
6974 | ||
6975 | void perf_event_namespaces(struct task_struct *task) | |
6976 | { | |
6977 | struct perf_namespaces_event namespaces_event; | |
6978 | struct perf_ns_link_info *ns_link_info; | |
6979 | ||
6980 | if (!atomic_read(&nr_namespaces_events)) | |
6981 | return; | |
6982 | ||
6983 | namespaces_event = (struct perf_namespaces_event){ | |
6984 | .task = task, | |
6985 | .event_id = { | |
6986 | .header = { | |
6987 | .type = PERF_RECORD_NAMESPACES, | |
6988 | .misc = 0, | |
6989 | .size = sizeof(namespaces_event.event_id), | |
6990 | }, | |
6991 | /* .pid */ | |
6992 | /* .tid */ | |
6993 | .nr_namespaces = NR_NAMESPACES, | |
6994 | /* .link_info[NR_NAMESPACES] */ | |
6995 | }, | |
6996 | }; | |
6997 | ||
6998 | ns_link_info = namespaces_event.event_id.link_info; | |
6999 | ||
7000 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7001 | task, &mntns_operations); | |
7002 | ||
7003 | #ifdef CONFIG_USER_NS | |
7004 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7005 | task, &userns_operations); | |
7006 | #endif | |
7007 | #ifdef CONFIG_NET_NS | |
7008 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7009 | task, &netns_operations); | |
7010 | #endif | |
7011 | #ifdef CONFIG_UTS_NS | |
7012 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7013 | task, &utsns_operations); | |
7014 | #endif | |
7015 | #ifdef CONFIG_IPC_NS | |
7016 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7017 | task, &ipcns_operations); | |
7018 | #endif | |
7019 | #ifdef CONFIG_PID_NS | |
7020 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7021 | task, &pidns_operations); | |
7022 | #endif | |
7023 | #ifdef CONFIG_CGROUPS | |
7024 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7025 | task, &cgroupns_operations); | |
7026 | #endif | |
7027 | ||
7028 | perf_iterate_sb(perf_event_namespaces_output, | |
7029 | &namespaces_event, | |
7030 | NULL); | |
7031 | } | |
7032 | ||
0a4a9391 PZ |
7033 | /* |
7034 | * mmap tracking | |
7035 | */ | |
7036 | ||
7037 | struct perf_mmap_event { | |
089dd79d PZ |
7038 | struct vm_area_struct *vma; |
7039 | ||
7040 | const char *file_name; | |
7041 | int file_size; | |
13d7a241 SE |
7042 | int maj, min; |
7043 | u64 ino; | |
7044 | u64 ino_generation; | |
f972eb63 | 7045 | u32 prot, flags; |
0a4a9391 PZ |
7046 | |
7047 | struct { | |
7048 | struct perf_event_header header; | |
7049 | ||
7050 | u32 pid; | |
7051 | u32 tid; | |
7052 | u64 start; | |
7053 | u64 len; | |
7054 | u64 pgoff; | |
cdd6c482 | 7055 | } event_id; |
0a4a9391 PZ |
7056 | }; |
7057 | ||
67516844 JO |
7058 | static int perf_event_mmap_match(struct perf_event *event, |
7059 | void *data) | |
7060 | { | |
7061 | struct perf_mmap_event *mmap_event = data; | |
7062 | struct vm_area_struct *vma = mmap_event->vma; | |
7063 | int executable = vma->vm_flags & VM_EXEC; | |
7064 | ||
7065 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7066 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7067 | } |
7068 | ||
cdd6c482 | 7069 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7070 | void *data) |
0a4a9391 | 7071 | { |
52d857a8 | 7072 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7073 | struct perf_output_handle handle; |
c980d109 | 7074 | struct perf_sample_data sample; |
cdd6c482 | 7075 | int size = mmap_event->event_id.header.size; |
c980d109 | 7076 | int ret; |
0a4a9391 | 7077 | |
67516844 JO |
7078 | if (!perf_event_mmap_match(event, data)) |
7079 | return; | |
7080 | ||
13d7a241 SE |
7081 | if (event->attr.mmap2) { |
7082 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7083 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7084 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7085 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7086 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7087 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7088 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7089 | } |
7090 | ||
c980d109 ACM |
7091 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7092 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7093 | mmap_event->event_id.header.size); |
0a4a9391 | 7094 | if (ret) |
c980d109 | 7095 | goto out; |
0a4a9391 | 7096 | |
cdd6c482 IM |
7097 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7098 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7099 | |
cdd6c482 | 7100 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7101 | |
7102 | if (event->attr.mmap2) { | |
7103 | perf_output_put(&handle, mmap_event->maj); | |
7104 | perf_output_put(&handle, mmap_event->min); | |
7105 | perf_output_put(&handle, mmap_event->ino); | |
7106 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7107 | perf_output_put(&handle, mmap_event->prot); |
7108 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7109 | } |
7110 | ||
76369139 | 7111 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7112 | mmap_event->file_size); |
c980d109 ACM |
7113 | |
7114 | perf_event__output_id_sample(event, &handle, &sample); | |
7115 | ||
78d613eb | 7116 | perf_output_end(&handle); |
c980d109 ACM |
7117 | out: |
7118 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
7119 | } |
7120 | ||
cdd6c482 | 7121 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7122 | { |
089dd79d PZ |
7123 | struct vm_area_struct *vma = mmap_event->vma; |
7124 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7125 | int maj = 0, min = 0; |
7126 | u64 ino = 0, gen = 0; | |
f972eb63 | 7127 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7128 | unsigned int size; |
7129 | char tmp[16]; | |
7130 | char *buf = NULL; | |
2c42cfbf | 7131 | char *name; |
413ee3b4 | 7132 | |
0b3589be PZ |
7133 | if (vma->vm_flags & VM_READ) |
7134 | prot |= PROT_READ; | |
7135 | if (vma->vm_flags & VM_WRITE) | |
7136 | prot |= PROT_WRITE; | |
7137 | if (vma->vm_flags & VM_EXEC) | |
7138 | prot |= PROT_EXEC; | |
7139 | ||
7140 | if (vma->vm_flags & VM_MAYSHARE) | |
7141 | flags = MAP_SHARED; | |
7142 | else | |
7143 | flags = MAP_PRIVATE; | |
7144 | ||
7145 | if (vma->vm_flags & VM_DENYWRITE) | |
7146 | flags |= MAP_DENYWRITE; | |
7147 | if (vma->vm_flags & VM_MAYEXEC) | |
7148 | flags |= MAP_EXECUTABLE; | |
7149 | if (vma->vm_flags & VM_LOCKED) | |
7150 | flags |= MAP_LOCKED; | |
7151 | if (vma->vm_flags & VM_HUGETLB) | |
7152 | flags |= MAP_HUGETLB; | |
7153 | ||
0a4a9391 | 7154 | if (file) { |
13d7a241 SE |
7155 | struct inode *inode; |
7156 | dev_t dev; | |
3ea2f2b9 | 7157 | |
2c42cfbf | 7158 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7159 | if (!buf) { |
c7e548b4 ON |
7160 | name = "//enomem"; |
7161 | goto cpy_name; | |
0a4a9391 | 7162 | } |
413ee3b4 | 7163 | /* |
3ea2f2b9 | 7164 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7165 | * need to add enough zero bytes after the string to handle |
7166 | * the 64bit alignment we do later. | |
7167 | */ | |
9bf39ab2 | 7168 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7169 | if (IS_ERR(name)) { |
c7e548b4 ON |
7170 | name = "//toolong"; |
7171 | goto cpy_name; | |
0a4a9391 | 7172 | } |
13d7a241 SE |
7173 | inode = file_inode(vma->vm_file); |
7174 | dev = inode->i_sb->s_dev; | |
7175 | ino = inode->i_ino; | |
7176 | gen = inode->i_generation; | |
7177 | maj = MAJOR(dev); | |
7178 | min = MINOR(dev); | |
f972eb63 | 7179 | |
c7e548b4 | 7180 | goto got_name; |
0a4a9391 | 7181 | } else { |
fbe26abe JO |
7182 | if (vma->vm_ops && vma->vm_ops->name) { |
7183 | name = (char *) vma->vm_ops->name(vma); | |
7184 | if (name) | |
7185 | goto cpy_name; | |
7186 | } | |
7187 | ||
2c42cfbf | 7188 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7189 | if (name) |
7190 | goto cpy_name; | |
089dd79d | 7191 | |
32c5fb7e | 7192 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7193 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7194 | name = "[heap]"; |
7195 | goto cpy_name; | |
32c5fb7e ON |
7196 | } |
7197 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7198 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7199 | name = "[stack]"; |
7200 | goto cpy_name; | |
089dd79d PZ |
7201 | } |
7202 | ||
c7e548b4 ON |
7203 | name = "//anon"; |
7204 | goto cpy_name; | |
0a4a9391 PZ |
7205 | } |
7206 | ||
c7e548b4 ON |
7207 | cpy_name: |
7208 | strlcpy(tmp, name, sizeof(tmp)); | |
7209 | name = tmp; | |
0a4a9391 | 7210 | got_name: |
2c42cfbf PZ |
7211 | /* |
7212 | * Since our buffer works in 8 byte units we need to align our string | |
7213 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7214 | * zero'd out to avoid leaking random bits to userspace. | |
7215 | */ | |
7216 | size = strlen(name)+1; | |
7217 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7218 | name[size++] = '\0'; | |
0a4a9391 PZ |
7219 | |
7220 | mmap_event->file_name = name; | |
7221 | mmap_event->file_size = size; | |
13d7a241 SE |
7222 | mmap_event->maj = maj; |
7223 | mmap_event->min = min; | |
7224 | mmap_event->ino = ino; | |
7225 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7226 | mmap_event->prot = prot; |
7227 | mmap_event->flags = flags; | |
0a4a9391 | 7228 | |
2fe85427 SE |
7229 | if (!(vma->vm_flags & VM_EXEC)) |
7230 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7231 | ||
cdd6c482 | 7232 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7233 | |
aab5b71e | 7234 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7235 | mmap_event, |
7236 | NULL); | |
665c2142 | 7237 | |
0a4a9391 PZ |
7238 | kfree(buf); |
7239 | } | |
7240 | ||
375637bc AS |
7241 | /* |
7242 | * Check whether inode and address range match filter criteria. | |
7243 | */ | |
7244 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7245 | struct file *file, unsigned long offset, | |
7246 | unsigned long size) | |
7247 | { | |
45063097 | 7248 | if (filter->inode != file_inode(file)) |
375637bc AS |
7249 | return false; |
7250 | ||
7251 | if (filter->offset > offset + size) | |
7252 | return false; | |
7253 | ||
7254 | if (filter->offset + filter->size < offset) | |
7255 | return false; | |
7256 | ||
7257 | return true; | |
7258 | } | |
7259 | ||
7260 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
7261 | { | |
7262 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7263 | struct vm_area_struct *vma = data; | |
7264 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
7265 | struct file *file = vma->vm_file; | |
7266 | struct perf_addr_filter *filter; | |
7267 | unsigned int restart = 0, count = 0; | |
7268 | ||
7269 | if (!has_addr_filter(event)) | |
7270 | return; | |
7271 | ||
7272 | if (!file) | |
7273 | return; | |
7274 | ||
7275 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7276 | list_for_each_entry(filter, &ifh->list, entry) { | |
7277 | if (perf_addr_filter_match(filter, file, off, | |
7278 | vma->vm_end - vma->vm_start)) { | |
7279 | event->addr_filters_offs[count] = vma->vm_start; | |
7280 | restart++; | |
7281 | } | |
7282 | ||
7283 | count++; | |
7284 | } | |
7285 | ||
7286 | if (restart) | |
7287 | event->addr_filters_gen++; | |
7288 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7289 | ||
7290 | if (restart) | |
767ae086 | 7291 | perf_event_stop(event, 1); |
375637bc AS |
7292 | } |
7293 | ||
7294 | /* | |
7295 | * Adjust all task's events' filters to the new vma | |
7296 | */ | |
7297 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7298 | { | |
7299 | struct perf_event_context *ctx; | |
7300 | int ctxn; | |
7301 | ||
12b40a23 MP |
7302 | /* |
7303 | * Data tracing isn't supported yet and as such there is no need | |
7304 | * to keep track of anything that isn't related to executable code: | |
7305 | */ | |
7306 | if (!(vma->vm_flags & VM_EXEC)) | |
7307 | return; | |
7308 | ||
375637bc AS |
7309 | rcu_read_lock(); |
7310 | for_each_task_context_nr(ctxn) { | |
7311 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7312 | if (!ctx) | |
7313 | continue; | |
7314 | ||
aab5b71e | 7315 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7316 | } |
7317 | rcu_read_unlock(); | |
7318 | } | |
7319 | ||
3af9e859 | 7320 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7321 | { |
9ee318a7 PZ |
7322 | struct perf_mmap_event mmap_event; |
7323 | ||
cdd6c482 | 7324 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7325 | return; |
7326 | ||
7327 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7328 | .vma = vma, |
573402db PZ |
7329 | /* .file_name */ |
7330 | /* .file_size */ | |
cdd6c482 | 7331 | .event_id = { |
573402db | 7332 | .header = { |
cdd6c482 | 7333 | .type = PERF_RECORD_MMAP, |
39447b38 | 7334 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7335 | /* .size */ |
7336 | }, | |
7337 | /* .pid */ | |
7338 | /* .tid */ | |
089dd79d PZ |
7339 | .start = vma->vm_start, |
7340 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7341 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7342 | }, |
13d7a241 SE |
7343 | /* .maj (attr_mmap2 only) */ |
7344 | /* .min (attr_mmap2 only) */ | |
7345 | /* .ino (attr_mmap2 only) */ | |
7346 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7347 | /* .prot (attr_mmap2 only) */ |
7348 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7349 | }; |
7350 | ||
375637bc | 7351 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7352 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7353 | } |
7354 | ||
68db7e98 AS |
7355 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7356 | unsigned long size, u64 flags) | |
7357 | { | |
7358 | struct perf_output_handle handle; | |
7359 | struct perf_sample_data sample; | |
7360 | struct perf_aux_event { | |
7361 | struct perf_event_header header; | |
7362 | u64 offset; | |
7363 | u64 size; | |
7364 | u64 flags; | |
7365 | } rec = { | |
7366 | .header = { | |
7367 | .type = PERF_RECORD_AUX, | |
7368 | .misc = 0, | |
7369 | .size = sizeof(rec), | |
7370 | }, | |
7371 | .offset = head, | |
7372 | .size = size, | |
7373 | .flags = flags, | |
7374 | }; | |
7375 | int ret; | |
7376 | ||
7377 | perf_event_header__init_id(&rec.header, &sample, event); | |
7378 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7379 | ||
7380 | if (ret) | |
7381 | return; | |
7382 | ||
7383 | perf_output_put(&handle, rec); | |
7384 | perf_event__output_id_sample(event, &handle, &sample); | |
7385 | ||
7386 | perf_output_end(&handle); | |
7387 | } | |
7388 | ||
f38b0dbb KL |
7389 | /* |
7390 | * Lost/dropped samples logging | |
7391 | */ | |
7392 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7393 | { | |
7394 | struct perf_output_handle handle; | |
7395 | struct perf_sample_data sample; | |
7396 | int ret; | |
7397 | ||
7398 | struct { | |
7399 | struct perf_event_header header; | |
7400 | u64 lost; | |
7401 | } lost_samples_event = { | |
7402 | .header = { | |
7403 | .type = PERF_RECORD_LOST_SAMPLES, | |
7404 | .misc = 0, | |
7405 | .size = sizeof(lost_samples_event), | |
7406 | }, | |
7407 | .lost = lost, | |
7408 | }; | |
7409 | ||
7410 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7411 | ||
7412 | ret = perf_output_begin(&handle, event, | |
7413 | lost_samples_event.header.size); | |
7414 | if (ret) | |
7415 | return; | |
7416 | ||
7417 | perf_output_put(&handle, lost_samples_event); | |
7418 | perf_event__output_id_sample(event, &handle, &sample); | |
7419 | perf_output_end(&handle); | |
7420 | } | |
7421 | ||
45ac1403 AH |
7422 | /* |
7423 | * context_switch tracking | |
7424 | */ | |
7425 | ||
7426 | struct perf_switch_event { | |
7427 | struct task_struct *task; | |
7428 | struct task_struct *next_prev; | |
7429 | ||
7430 | struct { | |
7431 | struct perf_event_header header; | |
7432 | u32 next_prev_pid; | |
7433 | u32 next_prev_tid; | |
7434 | } event_id; | |
7435 | }; | |
7436 | ||
7437 | static int perf_event_switch_match(struct perf_event *event) | |
7438 | { | |
7439 | return event->attr.context_switch; | |
7440 | } | |
7441 | ||
7442 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7443 | { | |
7444 | struct perf_switch_event *se = data; | |
7445 | struct perf_output_handle handle; | |
7446 | struct perf_sample_data sample; | |
7447 | int ret; | |
7448 | ||
7449 | if (!perf_event_switch_match(event)) | |
7450 | return; | |
7451 | ||
7452 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7453 | if (event->ctx->task) { | |
7454 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7455 | se->event_id.header.size = sizeof(se->event_id.header); | |
7456 | } else { | |
7457 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7458 | se->event_id.header.size = sizeof(se->event_id); | |
7459 | se->event_id.next_prev_pid = | |
7460 | perf_event_pid(event, se->next_prev); | |
7461 | se->event_id.next_prev_tid = | |
7462 | perf_event_tid(event, se->next_prev); | |
7463 | } | |
7464 | ||
7465 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7466 | ||
7467 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7468 | if (ret) | |
7469 | return; | |
7470 | ||
7471 | if (event->ctx->task) | |
7472 | perf_output_put(&handle, se->event_id.header); | |
7473 | else | |
7474 | perf_output_put(&handle, se->event_id); | |
7475 | ||
7476 | perf_event__output_id_sample(event, &handle, &sample); | |
7477 | ||
7478 | perf_output_end(&handle); | |
7479 | } | |
7480 | ||
7481 | static void perf_event_switch(struct task_struct *task, | |
7482 | struct task_struct *next_prev, bool sched_in) | |
7483 | { | |
7484 | struct perf_switch_event switch_event; | |
7485 | ||
7486 | /* N.B. caller checks nr_switch_events != 0 */ | |
7487 | ||
7488 | switch_event = (struct perf_switch_event){ | |
7489 | .task = task, | |
7490 | .next_prev = next_prev, | |
7491 | .event_id = { | |
7492 | .header = { | |
7493 | /* .type */ | |
7494 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7495 | /* .size */ | |
7496 | }, | |
7497 | /* .next_prev_pid */ | |
7498 | /* .next_prev_tid */ | |
7499 | }, | |
7500 | }; | |
7501 | ||
aab5b71e | 7502 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7503 | &switch_event, |
7504 | NULL); | |
7505 | } | |
7506 | ||
a78ac325 PZ |
7507 | /* |
7508 | * IRQ throttle logging | |
7509 | */ | |
7510 | ||
cdd6c482 | 7511 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7512 | { |
7513 | struct perf_output_handle handle; | |
c980d109 | 7514 | struct perf_sample_data sample; |
a78ac325 PZ |
7515 | int ret; |
7516 | ||
7517 | struct { | |
7518 | struct perf_event_header header; | |
7519 | u64 time; | |
cca3f454 | 7520 | u64 id; |
7f453c24 | 7521 | u64 stream_id; |
a78ac325 PZ |
7522 | } throttle_event = { |
7523 | .header = { | |
cdd6c482 | 7524 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7525 | .misc = 0, |
7526 | .size = sizeof(throttle_event), | |
7527 | }, | |
34f43927 | 7528 | .time = perf_event_clock(event), |
cdd6c482 IM |
7529 | .id = primary_event_id(event), |
7530 | .stream_id = event->id, | |
a78ac325 PZ |
7531 | }; |
7532 | ||
966ee4d6 | 7533 | if (enable) |
cdd6c482 | 7534 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7535 | |
c980d109 ACM |
7536 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7537 | ||
7538 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7539 | throttle_event.header.size); |
a78ac325 PZ |
7540 | if (ret) |
7541 | return; | |
7542 | ||
7543 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7544 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7545 | perf_output_end(&handle); |
7546 | } | |
7547 | ||
8d4e6c4c AS |
7548 | void perf_event_itrace_started(struct perf_event *event) |
7549 | { | |
7550 | event->attach_state |= PERF_ATTACH_ITRACE; | |
7551 | } | |
7552 | ||
ec0d7729 AS |
7553 | static void perf_log_itrace_start(struct perf_event *event) |
7554 | { | |
7555 | struct perf_output_handle handle; | |
7556 | struct perf_sample_data sample; | |
7557 | struct perf_aux_event { | |
7558 | struct perf_event_header header; | |
7559 | u32 pid; | |
7560 | u32 tid; | |
7561 | } rec; | |
7562 | int ret; | |
7563 | ||
7564 | if (event->parent) | |
7565 | event = event->parent; | |
7566 | ||
7567 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 7568 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
7569 | return; |
7570 | ||
ec0d7729 AS |
7571 | rec.header.type = PERF_RECORD_ITRACE_START; |
7572 | rec.header.misc = 0; | |
7573 | rec.header.size = sizeof(rec); | |
7574 | rec.pid = perf_event_pid(event, current); | |
7575 | rec.tid = perf_event_tid(event, current); | |
7576 | ||
7577 | perf_event_header__init_id(&rec.header, &sample, event); | |
7578 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7579 | ||
7580 | if (ret) | |
7581 | return; | |
7582 | ||
7583 | perf_output_put(&handle, rec); | |
7584 | perf_event__output_id_sample(event, &handle, &sample); | |
7585 | ||
7586 | perf_output_end(&handle); | |
7587 | } | |
7588 | ||
475113d9 JO |
7589 | static int |
7590 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7591 | { |
cdd6c482 | 7592 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7593 | int ret = 0; |
475113d9 | 7594 | u64 seq; |
96398826 | 7595 | |
e050e3f0 SE |
7596 | seq = __this_cpu_read(perf_throttled_seq); |
7597 | if (seq != hwc->interrupts_seq) { | |
7598 | hwc->interrupts_seq = seq; | |
7599 | hwc->interrupts = 1; | |
7600 | } else { | |
7601 | hwc->interrupts++; | |
7602 | if (unlikely(throttle | |
7603 | && hwc->interrupts >= max_samples_per_tick)) { | |
7604 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7605 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7606 | hwc->interrupts = MAX_INTERRUPTS; |
7607 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7608 | ret = 1; |
7609 | } | |
e050e3f0 | 7610 | } |
60db5e09 | 7611 | |
cdd6c482 | 7612 | if (event->attr.freq) { |
def0a9b2 | 7613 | u64 now = perf_clock(); |
abd50713 | 7614 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7615 | |
abd50713 | 7616 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7617 | |
abd50713 | 7618 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7619 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7620 | } |
7621 | ||
475113d9 JO |
7622 | return ret; |
7623 | } | |
7624 | ||
7625 | int perf_event_account_interrupt(struct perf_event *event) | |
7626 | { | |
7627 | return __perf_event_account_interrupt(event, 1); | |
7628 | } | |
7629 | ||
7630 | /* | |
7631 | * Generic event overflow handling, sampling. | |
7632 | */ | |
7633 | ||
7634 | static int __perf_event_overflow(struct perf_event *event, | |
7635 | int throttle, struct perf_sample_data *data, | |
7636 | struct pt_regs *regs) | |
7637 | { | |
7638 | int events = atomic_read(&event->event_limit); | |
7639 | int ret = 0; | |
7640 | ||
7641 | /* | |
7642 | * Non-sampling counters might still use the PMI to fold short | |
7643 | * hardware counters, ignore those. | |
7644 | */ | |
7645 | if (unlikely(!is_sampling_event(event))) | |
7646 | return 0; | |
7647 | ||
7648 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 7649 | |
2023b359 PZ |
7650 | /* |
7651 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7652 | * events |
2023b359 PZ |
7653 | */ |
7654 | ||
cdd6c482 IM |
7655 | event->pending_kill = POLL_IN; |
7656 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7657 | ret = 1; |
cdd6c482 | 7658 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7659 | |
7660 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7661 | } |
7662 | ||
aa6a5f3c | 7663 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7664 | |
fed66e2c | 7665 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7666 | event->pending_wakeup = 1; |
7667 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7668 | } |
7669 | ||
79f14641 | 7670 | return ret; |
f6c7d5fe PZ |
7671 | } |
7672 | ||
a8b0ca17 | 7673 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7674 | struct perf_sample_data *data, |
7675 | struct pt_regs *regs) | |
850bc73f | 7676 | { |
a8b0ca17 | 7677 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7678 | } |
7679 | ||
15dbf27c | 7680 | /* |
cdd6c482 | 7681 | * Generic software event infrastructure |
15dbf27c PZ |
7682 | */ |
7683 | ||
b28ab83c PZ |
7684 | struct swevent_htable { |
7685 | struct swevent_hlist *swevent_hlist; | |
7686 | struct mutex hlist_mutex; | |
7687 | int hlist_refcount; | |
7688 | ||
7689 | /* Recursion avoidance in each contexts */ | |
7690 | int recursion[PERF_NR_CONTEXTS]; | |
7691 | }; | |
7692 | ||
7693 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7694 | ||
7b4b6658 | 7695 | /* |
cdd6c482 IM |
7696 | * We directly increment event->count and keep a second value in |
7697 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7698 | * is kept in the range [-sample_period, 0] so that we can use the |
7699 | * sign as trigger. | |
7700 | */ | |
7701 | ||
ab573844 | 7702 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7703 | { |
cdd6c482 | 7704 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7705 | u64 period = hwc->last_period; |
7706 | u64 nr, offset; | |
7707 | s64 old, val; | |
7708 | ||
7709 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7710 | |
7711 | again: | |
e7850595 | 7712 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7713 | if (val < 0) |
7714 | return 0; | |
15dbf27c | 7715 | |
7b4b6658 PZ |
7716 | nr = div64_u64(period + val, period); |
7717 | offset = nr * period; | |
7718 | val -= offset; | |
e7850595 | 7719 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7720 | goto again; |
15dbf27c | 7721 | |
7b4b6658 | 7722 | return nr; |
15dbf27c PZ |
7723 | } |
7724 | ||
0cff784a | 7725 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7726 | struct perf_sample_data *data, |
5622f295 | 7727 | struct pt_regs *regs) |
15dbf27c | 7728 | { |
cdd6c482 | 7729 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7730 | int throttle = 0; |
15dbf27c | 7731 | |
0cff784a PZ |
7732 | if (!overflow) |
7733 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7734 | |
7b4b6658 PZ |
7735 | if (hwc->interrupts == MAX_INTERRUPTS) |
7736 | return; | |
15dbf27c | 7737 | |
7b4b6658 | 7738 | for (; overflow; overflow--) { |
a8b0ca17 | 7739 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7740 | data, regs)) { |
7b4b6658 PZ |
7741 | /* |
7742 | * We inhibit the overflow from happening when | |
7743 | * hwc->interrupts == MAX_INTERRUPTS. | |
7744 | */ | |
7745 | break; | |
7746 | } | |
cf450a73 | 7747 | throttle = 1; |
7b4b6658 | 7748 | } |
15dbf27c PZ |
7749 | } |
7750 | ||
a4eaf7f1 | 7751 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7752 | struct perf_sample_data *data, |
5622f295 | 7753 | struct pt_regs *regs) |
7b4b6658 | 7754 | { |
cdd6c482 | 7755 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7756 | |
e7850595 | 7757 | local64_add(nr, &event->count); |
d6d020e9 | 7758 | |
0cff784a PZ |
7759 | if (!regs) |
7760 | return; | |
7761 | ||
6c7e550f | 7762 | if (!is_sampling_event(event)) |
7b4b6658 | 7763 | return; |
d6d020e9 | 7764 | |
5d81e5cf AV |
7765 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7766 | data->period = nr; | |
7767 | return perf_swevent_overflow(event, 1, data, regs); | |
7768 | } else | |
7769 | data->period = event->hw.last_period; | |
7770 | ||
0cff784a | 7771 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7772 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7773 | |
e7850595 | 7774 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7775 | return; |
df1a132b | 7776 | |
a8b0ca17 | 7777 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7778 | } |
7779 | ||
f5ffe02e FW |
7780 | static int perf_exclude_event(struct perf_event *event, |
7781 | struct pt_regs *regs) | |
7782 | { | |
a4eaf7f1 | 7783 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7784 | return 1; |
a4eaf7f1 | 7785 | |
f5ffe02e FW |
7786 | if (regs) { |
7787 | if (event->attr.exclude_user && user_mode(regs)) | |
7788 | return 1; | |
7789 | ||
7790 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7791 | return 1; | |
7792 | } | |
7793 | ||
7794 | return 0; | |
7795 | } | |
7796 | ||
cdd6c482 | 7797 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7798 | enum perf_type_id type, |
6fb2915d LZ |
7799 | u32 event_id, |
7800 | struct perf_sample_data *data, | |
7801 | struct pt_regs *regs) | |
15dbf27c | 7802 | { |
cdd6c482 | 7803 | if (event->attr.type != type) |
a21ca2ca | 7804 | return 0; |
f5ffe02e | 7805 | |
cdd6c482 | 7806 | if (event->attr.config != event_id) |
15dbf27c PZ |
7807 | return 0; |
7808 | ||
f5ffe02e FW |
7809 | if (perf_exclude_event(event, regs)) |
7810 | return 0; | |
15dbf27c PZ |
7811 | |
7812 | return 1; | |
7813 | } | |
7814 | ||
76e1d904 FW |
7815 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7816 | { | |
7817 | u64 val = event_id | (type << 32); | |
7818 | ||
7819 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7820 | } | |
7821 | ||
49f135ed FW |
7822 | static inline struct hlist_head * |
7823 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7824 | { |
49f135ed FW |
7825 | u64 hash = swevent_hash(type, event_id); |
7826 | ||
7827 | return &hlist->heads[hash]; | |
7828 | } | |
76e1d904 | 7829 | |
49f135ed FW |
7830 | /* For the read side: events when they trigger */ |
7831 | static inline struct hlist_head * | |
b28ab83c | 7832 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7833 | { |
7834 | struct swevent_hlist *hlist; | |
76e1d904 | 7835 | |
b28ab83c | 7836 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7837 | if (!hlist) |
7838 | return NULL; | |
7839 | ||
49f135ed FW |
7840 | return __find_swevent_head(hlist, type, event_id); |
7841 | } | |
7842 | ||
7843 | /* For the event head insertion and removal in the hlist */ | |
7844 | static inline struct hlist_head * | |
b28ab83c | 7845 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7846 | { |
7847 | struct swevent_hlist *hlist; | |
7848 | u32 event_id = event->attr.config; | |
7849 | u64 type = event->attr.type; | |
7850 | ||
7851 | /* | |
7852 | * Event scheduling is always serialized against hlist allocation | |
7853 | * and release. Which makes the protected version suitable here. | |
7854 | * The context lock guarantees that. | |
7855 | */ | |
b28ab83c | 7856 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7857 | lockdep_is_held(&event->ctx->lock)); |
7858 | if (!hlist) | |
7859 | return NULL; | |
7860 | ||
7861 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7862 | } |
7863 | ||
7864 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7865 | u64 nr, |
76e1d904 FW |
7866 | struct perf_sample_data *data, |
7867 | struct pt_regs *regs) | |
15dbf27c | 7868 | { |
4a32fea9 | 7869 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7870 | struct perf_event *event; |
76e1d904 | 7871 | struct hlist_head *head; |
15dbf27c | 7872 | |
76e1d904 | 7873 | rcu_read_lock(); |
b28ab83c | 7874 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7875 | if (!head) |
7876 | goto end; | |
7877 | ||
b67bfe0d | 7878 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7879 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7880 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7881 | } |
76e1d904 FW |
7882 | end: |
7883 | rcu_read_unlock(); | |
15dbf27c PZ |
7884 | } |
7885 | ||
86038c5e PZI |
7886 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7887 | ||
4ed7c92d | 7888 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7889 | { |
4a32fea9 | 7890 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7891 | |
b28ab83c | 7892 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7893 | } |
645e8cc0 | 7894 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7895 | |
98b5c2c6 | 7896 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7897 | { |
4a32fea9 | 7898 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7899 | |
b28ab83c | 7900 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7901 | } |
15dbf27c | 7902 | |
86038c5e | 7903 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7904 | { |
a4234bfc | 7905 | struct perf_sample_data data; |
4ed7c92d | 7906 | |
86038c5e | 7907 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7908 | return; |
a4234bfc | 7909 | |
fd0d000b | 7910 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7911 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7912 | } |
7913 | ||
7914 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7915 | { | |
7916 | int rctx; | |
7917 | ||
7918 | preempt_disable_notrace(); | |
7919 | rctx = perf_swevent_get_recursion_context(); | |
7920 | if (unlikely(rctx < 0)) | |
7921 | goto fail; | |
7922 | ||
7923 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7924 | |
7925 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7926 | fail: |
1c024eca | 7927 | preempt_enable_notrace(); |
b8e83514 PZ |
7928 | } |
7929 | ||
cdd6c482 | 7930 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7931 | { |
15dbf27c PZ |
7932 | } |
7933 | ||
a4eaf7f1 | 7934 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7935 | { |
4a32fea9 | 7936 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7937 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7938 | struct hlist_head *head; |
7939 | ||
6c7e550f | 7940 | if (is_sampling_event(event)) { |
7b4b6658 | 7941 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7942 | perf_swevent_set_period(event); |
7b4b6658 | 7943 | } |
76e1d904 | 7944 | |
a4eaf7f1 PZ |
7945 | hwc->state = !(flags & PERF_EF_START); |
7946 | ||
b28ab83c | 7947 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7948 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7949 | return -EINVAL; |
7950 | ||
7951 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7952 | perf_event_update_userpage(event); |
76e1d904 | 7953 | |
15dbf27c PZ |
7954 | return 0; |
7955 | } | |
7956 | ||
a4eaf7f1 | 7957 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7958 | { |
76e1d904 | 7959 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7960 | } |
7961 | ||
a4eaf7f1 | 7962 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7963 | { |
a4eaf7f1 | 7964 | event->hw.state = 0; |
d6d020e9 | 7965 | } |
aa9c4c0f | 7966 | |
a4eaf7f1 | 7967 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7968 | { |
a4eaf7f1 | 7969 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7970 | } |
7971 | ||
49f135ed FW |
7972 | /* Deref the hlist from the update side */ |
7973 | static inline struct swevent_hlist * | |
b28ab83c | 7974 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7975 | { |
b28ab83c PZ |
7976 | return rcu_dereference_protected(swhash->swevent_hlist, |
7977 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7978 | } |
7979 | ||
b28ab83c | 7980 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7981 | { |
b28ab83c | 7982 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7983 | |
49f135ed | 7984 | if (!hlist) |
76e1d904 FW |
7985 | return; |
7986 | ||
70691d4a | 7987 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7988 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7989 | } |
7990 | ||
3b364d7b | 7991 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7992 | { |
b28ab83c | 7993 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7994 | |
b28ab83c | 7995 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7996 | |
b28ab83c PZ |
7997 | if (!--swhash->hlist_refcount) |
7998 | swevent_hlist_release(swhash); | |
76e1d904 | 7999 | |
b28ab83c | 8000 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8001 | } |
8002 | ||
3b364d7b | 8003 | static void swevent_hlist_put(void) |
76e1d904 FW |
8004 | { |
8005 | int cpu; | |
8006 | ||
76e1d904 | 8007 | for_each_possible_cpu(cpu) |
3b364d7b | 8008 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8009 | } |
8010 | ||
3b364d7b | 8011 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8012 | { |
b28ab83c | 8013 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8014 | int err = 0; |
8015 | ||
b28ab83c | 8016 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8017 | if (!swevent_hlist_deref(swhash) && |
8018 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8019 | struct swevent_hlist *hlist; |
8020 | ||
8021 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8022 | if (!hlist) { | |
8023 | err = -ENOMEM; | |
8024 | goto exit; | |
8025 | } | |
b28ab83c | 8026 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8027 | } |
b28ab83c | 8028 | swhash->hlist_refcount++; |
9ed6060d | 8029 | exit: |
b28ab83c | 8030 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8031 | |
8032 | return err; | |
8033 | } | |
8034 | ||
3b364d7b | 8035 | static int swevent_hlist_get(void) |
76e1d904 | 8036 | { |
3b364d7b | 8037 | int err, cpu, failed_cpu; |
76e1d904 | 8038 | |
a63fbed7 | 8039 | mutex_lock(&pmus_lock); |
76e1d904 | 8040 | for_each_possible_cpu(cpu) { |
3b364d7b | 8041 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8042 | if (err) { |
8043 | failed_cpu = cpu; | |
8044 | goto fail; | |
8045 | } | |
8046 | } | |
a63fbed7 | 8047 | mutex_unlock(&pmus_lock); |
76e1d904 | 8048 | return 0; |
9ed6060d | 8049 | fail: |
76e1d904 FW |
8050 | for_each_possible_cpu(cpu) { |
8051 | if (cpu == failed_cpu) | |
8052 | break; | |
3b364d7b | 8053 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8054 | } |
a63fbed7 | 8055 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8056 | return err; |
8057 | } | |
8058 | ||
c5905afb | 8059 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8060 | |
b0a873eb PZ |
8061 | static void sw_perf_event_destroy(struct perf_event *event) |
8062 | { | |
8063 | u64 event_id = event->attr.config; | |
95476b64 | 8064 | |
b0a873eb PZ |
8065 | WARN_ON(event->parent); |
8066 | ||
c5905afb | 8067 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8068 | swevent_hlist_put(); |
b0a873eb PZ |
8069 | } |
8070 | ||
8071 | static int perf_swevent_init(struct perf_event *event) | |
8072 | { | |
8176cced | 8073 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8074 | |
8075 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8076 | return -ENOENT; | |
8077 | ||
2481c5fa SE |
8078 | /* |
8079 | * no branch sampling for software events | |
8080 | */ | |
8081 | if (has_branch_stack(event)) | |
8082 | return -EOPNOTSUPP; | |
8083 | ||
b0a873eb PZ |
8084 | switch (event_id) { |
8085 | case PERF_COUNT_SW_CPU_CLOCK: | |
8086 | case PERF_COUNT_SW_TASK_CLOCK: | |
8087 | return -ENOENT; | |
8088 | ||
8089 | default: | |
8090 | break; | |
8091 | } | |
8092 | ||
ce677831 | 8093 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8094 | return -ENOENT; |
8095 | ||
8096 | if (!event->parent) { | |
8097 | int err; | |
8098 | ||
3b364d7b | 8099 | err = swevent_hlist_get(); |
b0a873eb PZ |
8100 | if (err) |
8101 | return err; | |
8102 | ||
c5905afb | 8103 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8104 | event->destroy = sw_perf_event_destroy; |
8105 | } | |
8106 | ||
8107 | return 0; | |
8108 | } | |
8109 | ||
8110 | static struct pmu perf_swevent = { | |
89a1e187 | 8111 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8112 | |
34f43927 PZ |
8113 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8114 | ||
b0a873eb | 8115 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8116 | .add = perf_swevent_add, |
8117 | .del = perf_swevent_del, | |
8118 | .start = perf_swevent_start, | |
8119 | .stop = perf_swevent_stop, | |
1c024eca | 8120 | .read = perf_swevent_read, |
1c024eca PZ |
8121 | }; |
8122 | ||
b0a873eb PZ |
8123 | #ifdef CONFIG_EVENT_TRACING |
8124 | ||
1c024eca PZ |
8125 | static int perf_tp_filter_match(struct perf_event *event, |
8126 | struct perf_sample_data *data) | |
8127 | { | |
7e3f977e | 8128 | void *record = data->raw->frag.data; |
1c024eca | 8129 | |
b71b437e PZ |
8130 | /* only top level events have filters set */ |
8131 | if (event->parent) | |
8132 | event = event->parent; | |
8133 | ||
1c024eca PZ |
8134 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8135 | return 1; | |
8136 | return 0; | |
8137 | } | |
8138 | ||
8139 | static int perf_tp_event_match(struct perf_event *event, | |
8140 | struct perf_sample_data *data, | |
8141 | struct pt_regs *regs) | |
8142 | { | |
a0f7d0f7 FW |
8143 | if (event->hw.state & PERF_HES_STOPPED) |
8144 | return 0; | |
580d607c PZ |
8145 | /* |
8146 | * All tracepoints are from kernel-space. | |
8147 | */ | |
8148 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
8149 | return 0; |
8150 | ||
8151 | if (!perf_tp_filter_match(event, data)) | |
8152 | return 0; | |
8153 | ||
8154 | return 1; | |
8155 | } | |
8156 | ||
85b67bcb AS |
8157 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8158 | struct trace_event_call *call, u64 count, | |
8159 | struct pt_regs *regs, struct hlist_head *head, | |
8160 | struct task_struct *task) | |
8161 | { | |
e87c6bc3 | 8162 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8163 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8164 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8165 | perf_swevent_put_recursion_context(rctx); |
8166 | return; | |
8167 | } | |
8168 | } | |
8169 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8170 | rctx, task); |
85b67bcb AS |
8171 | } |
8172 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8173 | ||
1e1dcd93 | 8174 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8175 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8176 | struct task_struct *task) |
95476b64 FW |
8177 | { |
8178 | struct perf_sample_data data; | |
8fd0fbbe | 8179 | struct perf_event *event; |
1c024eca | 8180 | |
95476b64 | 8181 | struct perf_raw_record raw = { |
7e3f977e DB |
8182 | .frag = { |
8183 | .size = entry_size, | |
8184 | .data = record, | |
8185 | }, | |
95476b64 FW |
8186 | }; |
8187 | ||
1e1dcd93 | 8188 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8189 | data.raw = &raw; |
8190 | ||
1e1dcd93 AS |
8191 | perf_trace_buf_update(record, event_type); |
8192 | ||
8fd0fbbe | 8193 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8194 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8195 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8196 | } |
ecc55f84 | 8197 | |
e6dab5ff AV |
8198 | /* |
8199 | * If we got specified a target task, also iterate its context and | |
8200 | * deliver this event there too. | |
8201 | */ | |
8202 | if (task && task != current) { | |
8203 | struct perf_event_context *ctx; | |
8204 | struct trace_entry *entry = record; | |
8205 | ||
8206 | rcu_read_lock(); | |
8207 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8208 | if (!ctx) | |
8209 | goto unlock; | |
8210 | ||
8211 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
8212 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
8213 | continue; | |
8214 | if (event->attr.config != entry->type) | |
8215 | continue; | |
8216 | if (perf_tp_event_match(event, &data, regs)) | |
8217 | perf_swevent_event(event, count, &data, regs); | |
8218 | } | |
8219 | unlock: | |
8220 | rcu_read_unlock(); | |
8221 | } | |
8222 | ||
ecc55f84 | 8223 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8224 | } |
8225 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8226 | ||
cdd6c482 | 8227 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8228 | { |
1c024eca | 8229 | perf_trace_destroy(event); |
e077df4f PZ |
8230 | } |
8231 | ||
b0a873eb | 8232 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8233 | { |
76e1d904 FW |
8234 | int err; |
8235 | ||
b0a873eb PZ |
8236 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8237 | return -ENOENT; | |
8238 | ||
2481c5fa SE |
8239 | /* |
8240 | * no branch sampling for tracepoint events | |
8241 | */ | |
8242 | if (has_branch_stack(event)) | |
8243 | return -EOPNOTSUPP; | |
8244 | ||
1c024eca PZ |
8245 | err = perf_trace_init(event); |
8246 | if (err) | |
b0a873eb | 8247 | return err; |
e077df4f | 8248 | |
cdd6c482 | 8249 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8250 | |
b0a873eb PZ |
8251 | return 0; |
8252 | } | |
8253 | ||
8254 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8255 | .task_ctx_nr = perf_sw_context, |
8256 | ||
b0a873eb | 8257 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8258 | .add = perf_trace_add, |
8259 | .del = perf_trace_del, | |
8260 | .start = perf_swevent_start, | |
8261 | .stop = perf_swevent_stop, | |
b0a873eb | 8262 | .read = perf_swevent_read, |
b0a873eb PZ |
8263 | }; |
8264 | ||
33ea4b24 | 8265 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
8266 | /* |
8267 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
8268 | * The flags should match following PMU_FORMAT_ATTR(). | |
8269 | * | |
8270 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
8271 | * if not set, create kprobe/uprobe | |
8272 | */ | |
8273 | enum perf_probe_config { | |
8274 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
8275 | }; | |
8276 | ||
8277 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
8278 | ||
8279 | static struct attribute *probe_attrs[] = { | |
8280 | &format_attr_retprobe.attr, | |
8281 | NULL, | |
8282 | }; | |
8283 | ||
8284 | static struct attribute_group probe_format_group = { | |
8285 | .name = "format", | |
8286 | .attrs = probe_attrs, | |
8287 | }; | |
8288 | ||
8289 | static const struct attribute_group *probe_attr_groups[] = { | |
8290 | &probe_format_group, | |
8291 | NULL, | |
8292 | }; | |
33ea4b24 | 8293 | #endif |
e12f03d7 | 8294 | |
33ea4b24 | 8295 | #ifdef CONFIG_KPROBE_EVENTS |
e12f03d7 SL |
8296 | static int perf_kprobe_event_init(struct perf_event *event); |
8297 | static struct pmu perf_kprobe = { | |
8298 | .task_ctx_nr = perf_sw_context, | |
8299 | .event_init = perf_kprobe_event_init, | |
8300 | .add = perf_trace_add, | |
8301 | .del = perf_trace_del, | |
8302 | .start = perf_swevent_start, | |
8303 | .stop = perf_swevent_stop, | |
8304 | .read = perf_swevent_read, | |
8305 | .attr_groups = probe_attr_groups, | |
8306 | }; | |
8307 | ||
8308 | static int perf_kprobe_event_init(struct perf_event *event) | |
8309 | { | |
8310 | int err; | |
8311 | bool is_retprobe; | |
8312 | ||
8313 | if (event->attr.type != perf_kprobe.type) | |
8314 | return -ENOENT; | |
8315 | /* | |
8316 | * no branch sampling for probe events | |
8317 | */ | |
8318 | if (has_branch_stack(event)) | |
8319 | return -EOPNOTSUPP; | |
8320 | ||
8321 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8322 | err = perf_kprobe_init(event, is_retprobe); | |
8323 | if (err) | |
8324 | return err; | |
8325 | ||
8326 | event->destroy = perf_kprobe_destroy; | |
8327 | ||
8328 | return 0; | |
8329 | } | |
8330 | #endif /* CONFIG_KPROBE_EVENTS */ | |
8331 | ||
33ea4b24 SL |
8332 | #ifdef CONFIG_UPROBE_EVENTS |
8333 | static int perf_uprobe_event_init(struct perf_event *event); | |
8334 | static struct pmu perf_uprobe = { | |
8335 | .task_ctx_nr = perf_sw_context, | |
8336 | .event_init = perf_uprobe_event_init, | |
8337 | .add = perf_trace_add, | |
8338 | .del = perf_trace_del, | |
8339 | .start = perf_swevent_start, | |
8340 | .stop = perf_swevent_stop, | |
8341 | .read = perf_swevent_read, | |
8342 | .attr_groups = probe_attr_groups, | |
8343 | }; | |
8344 | ||
8345 | static int perf_uprobe_event_init(struct perf_event *event) | |
8346 | { | |
8347 | int err; | |
8348 | bool is_retprobe; | |
8349 | ||
8350 | if (event->attr.type != perf_uprobe.type) | |
8351 | return -ENOENT; | |
8352 | /* | |
8353 | * no branch sampling for probe events | |
8354 | */ | |
8355 | if (has_branch_stack(event)) | |
8356 | return -EOPNOTSUPP; | |
8357 | ||
8358 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8359 | err = perf_uprobe_init(event, is_retprobe); | |
8360 | if (err) | |
8361 | return err; | |
8362 | ||
8363 | event->destroy = perf_uprobe_destroy; | |
8364 | ||
8365 | return 0; | |
8366 | } | |
8367 | #endif /* CONFIG_UPROBE_EVENTS */ | |
8368 | ||
b0a873eb PZ |
8369 | static inline void perf_tp_register(void) |
8370 | { | |
2e80a82a | 8371 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
8372 | #ifdef CONFIG_KPROBE_EVENTS |
8373 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
8374 | #endif | |
33ea4b24 SL |
8375 | #ifdef CONFIG_UPROBE_EVENTS |
8376 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
8377 | #endif | |
e077df4f | 8378 | } |
6fb2915d | 8379 | |
6fb2915d LZ |
8380 | static void perf_event_free_filter(struct perf_event *event) |
8381 | { | |
8382 | ftrace_profile_free_filter(event); | |
8383 | } | |
8384 | ||
aa6a5f3c AS |
8385 | #ifdef CONFIG_BPF_SYSCALL |
8386 | static void bpf_overflow_handler(struct perf_event *event, | |
8387 | struct perf_sample_data *data, | |
8388 | struct pt_regs *regs) | |
8389 | { | |
8390 | struct bpf_perf_event_data_kern ctx = { | |
8391 | .data = data, | |
7d9285e8 | 8392 | .event = event, |
aa6a5f3c AS |
8393 | }; |
8394 | int ret = 0; | |
8395 | ||
c895f6f7 | 8396 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
8397 | preempt_disable(); |
8398 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
8399 | goto out; | |
8400 | rcu_read_lock(); | |
88575199 | 8401 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
8402 | rcu_read_unlock(); |
8403 | out: | |
8404 | __this_cpu_dec(bpf_prog_active); | |
8405 | preempt_enable(); | |
8406 | if (!ret) | |
8407 | return; | |
8408 | ||
8409 | event->orig_overflow_handler(event, data, regs); | |
8410 | } | |
8411 | ||
8412 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8413 | { | |
8414 | struct bpf_prog *prog; | |
8415 | ||
8416 | if (event->overflow_handler_context) | |
8417 | /* hw breakpoint or kernel counter */ | |
8418 | return -EINVAL; | |
8419 | ||
8420 | if (event->prog) | |
8421 | return -EEXIST; | |
8422 | ||
8423 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8424 | if (IS_ERR(prog)) | |
8425 | return PTR_ERR(prog); | |
8426 | ||
8427 | event->prog = prog; | |
8428 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8429 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8430 | return 0; | |
8431 | } | |
8432 | ||
8433 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8434 | { | |
8435 | struct bpf_prog *prog = event->prog; | |
8436 | ||
8437 | if (!prog) | |
8438 | return; | |
8439 | ||
8440 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
8441 | event->prog = NULL; | |
8442 | bpf_prog_put(prog); | |
8443 | } | |
8444 | #else | |
8445 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8446 | { | |
8447 | return -EOPNOTSUPP; | |
8448 | } | |
8449 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8450 | { | |
8451 | } | |
8452 | #endif | |
8453 | ||
e12f03d7 SL |
8454 | /* |
8455 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
8456 | * with perf_event_open() | |
8457 | */ | |
8458 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
8459 | { | |
8460 | if (event->pmu == &perf_tracepoint) | |
8461 | return true; | |
8462 | #ifdef CONFIG_KPROBE_EVENTS | |
8463 | if (event->pmu == &perf_kprobe) | |
8464 | return true; | |
33ea4b24 SL |
8465 | #endif |
8466 | #ifdef CONFIG_UPROBE_EVENTS | |
8467 | if (event->pmu == &perf_uprobe) | |
8468 | return true; | |
e12f03d7 SL |
8469 | #endif |
8470 | return false; | |
8471 | } | |
8472 | ||
2541517c AS |
8473 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8474 | { | |
cf5f5cea | 8475 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 8476 | struct bpf_prog *prog; |
e87c6bc3 | 8477 | int ret; |
2541517c | 8478 | |
e12f03d7 | 8479 | if (!perf_event_is_tracing(event)) |
f91840a3 | 8480 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 8481 | |
98b5c2c6 AS |
8482 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
8483 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
8484 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
8485 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 8486 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
8487 | return -EINVAL; |
8488 | ||
8489 | prog = bpf_prog_get(prog_fd); | |
8490 | if (IS_ERR(prog)) | |
8491 | return PTR_ERR(prog); | |
8492 | ||
98b5c2c6 | 8493 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
8494 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
8495 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
8496 | /* valid fd, but invalid bpf program type */ |
8497 | bpf_prog_put(prog); | |
8498 | return -EINVAL; | |
8499 | } | |
8500 | ||
9802d865 JB |
8501 | /* Kprobe override only works for kprobes, not uprobes. */ |
8502 | if (prog->kprobe_override && | |
8503 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
8504 | bpf_prog_put(prog); | |
8505 | return -EINVAL; | |
8506 | } | |
8507 | ||
cf5f5cea | 8508 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
8509 | int off = trace_event_get_offsets(event->tp_event); |
8510 | ||
8511 | if (prog->aux->max_ctx_offset > off) { | |
8512 | bpf_prog_put(prog); | |
8513 | return -EACCES; | |
8514 | } | |
8515 | } | |
2541517c | 8516 | |
e87c6bc3 YS |
8517 | ret = perf_event_attach_bpf_prog(event, prog); |
8518 | if (ret) | |
8519 | bpf_prog_put(prog); | |
8520 | return ret; | |
2541517c AS |
8521 | } |
8522 | ||
8523 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8524 | { | |
e12f03d7 | 8525 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 8526 | perf_event_free_bpf_handler(event); |
2541517c | 8527 | return; |
2541517c | 8528 | } |
e87c6bc3 | 8529 | perf_event_detach_bpf_prog(event); |
2541517c AS |
8530 | } |
8531 | ||
e077df4f | 8532 | #else |
6fb2915d | 8533 | |
b0a873eb | 8534 | static inline void perf_tp_register(void) |
e077df4f | 8535 | { |
e077df4f | 8536 | } |
6fb2915d | 8537 | |
6fb2915d LZ |
8538 | static void perf_event_free_filter(struct perf_event *event) |
8539 | { | |
8540 | } | |
8541 | ||
2541517c AS |
8542 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8543 | { | |
8544 | return -ENOENT; | |
8545 | } | |
8546 | ||
8547 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8548 | { | |
8549 | } | |
07b139c8 | 8550 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 8551 | |
24f1e32c | 8552 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 8553 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 8554 | { |
f5ffe02e FW |
8555 | struct perf_sample_data sample; |
8556 | struct pt_regs *regs = data; | |
8557 | ||
fd0d000b | 8558 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 8559 | |
a4eaf7f1 | 8560 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 8561 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
8562 | } |
8563 | #endif | |
8564 | ||
375637bc AS |
8565 | /* |
8566 | * Allocate a new address filter | |
8567 | */ | |
8568 | static struct perf_addr_filter * | |
8569 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
8570 | { | |
8571 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
8572 | struct perf_addr_filter *filter; | |
8573 | ||
8574 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
8575 | if (!filter) | |
8576 | return NULL; | |
8577 | ||
8578 | INIT_LIST_HEAD(&filter->entry); | |
8579 | list_add_tail(&filter->entry, filters); | |
8580 | ||
8581 | return filter; | |
8582 | } | |
8583 | ||
8584 | static void free_filters_list(struct list_head *filters) | |
8585 | { | |
8586 | struct perf_addr_filter *filter, *iter; | |
8587 | ||
8588 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
8589 | if (filter->inode) | |
8590 | iput(filter->inode); | |
8591 | list_del(&filter->entry); | |
8592 | kfree(filter); | |
8593 | } | |
8594 | } | |
8595 | ||
8596 | /* | |
8597 | * Free existing address filters and optionally install new ones | |
8598 | */ | |
8599 | static void perf_addr_filters_splice(struct perf_event *event, | |
8600 | struct list_head *head) | |
8601 | { | |
8602 | unsigned long flags; | |
8603 | LIST_HEAD(list); | |
8604 | ||
8605 | if (!has_addr_filter(event)) | |
8606 | return; | |
8607 | ||
8608 | /* don't bother with children, they don't have their own filters */ | |
8609 | if (event->parent) | |
8610 | return; | |
8611 | ||
8612 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
8613 | ||
8614 | list_splice_init(&event->addr_filters.list, &list); | |
8615 | if (head) | |
8616 | list_splice(head, &event->addr_filters.list); | |
8617 | ||
8618 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
8619 | ||
8620 | free_filters_list(&list); | |
8621 | } | |
8622 | ||
8623 | /* | |
8624 | * Scan through mm's vmas and see if one of them matches the | |
8625 | * @filter; if so, adjust filter's address range. | |
8626 | * Called with mm::mmap_sem down for reading. | |
8627 | */ | |
8628 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8629 | struct mm_struct *mm) | |
8630 | { | |
8631 | struct vm_area_struct *vma; | |
8632 | ||
8633 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8634 | struct file *file = vma->vm_file; | |
8635 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8636 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8637 | ||
8638 | if (!file) | |
8639 | continue; | |
8640 | ||
8641 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8642 | continue; | |
8643 | ||
8644 | return vma->vm_start; | |
8645 | } | |
8646 | ||
8647 | return 0; | |
8648 | } | |
8649 | ||
8650 | /* | |
8651 | * Update event's address range filters based on the | |
8652 | * task's existing mappings, if any. | |
8653 | */ | |
8654 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8655 | { | |
8656 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8657 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8658 | struct perf_addr_filter *filter; | |
8659 | struct mm_struct *mm = NULL; | |
8660 | unsigned int count = 0; | |
8661 | unsigned long flags; | |
8662 | ||
8663 | /* | |
8664 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8665 | * will stop on the parent's child_mutex that our caller is also holding | |
8666 | */ | |
8667 | if (task == TASK_TOMBSTONE) | |
8668 | return; | |
8669 | ||
6ce77bfd AS |
8670 | if (!ifh->nr_file_filters) |
8671 | return; | |
8672 | ||
375637bc AS |
8673 | mm = get_task_mm(event->ctx->task); |
8674 | if (!mm) | |
8675 | goto restart; | |
8676 | ||
8677 | down_read(&mm->mmap_sem); | |
8678 | ||
8679 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8680 | list_for_each_entry(filter, &ifh->list, entry) { | |
8681 | event->addr_filters_offs[count] = 0; | |
8682 | ||
99f5bc9b MP |
8683 | /* |
8684 | * Adjust base offset if the filter is associated to a binary | |
8685 | * that needs to be mapped: | |
8686 | */ | |
8687 | if (filter->inode) | |
375637bc AS |
8688 | event->addr_filters_offs[count] = |
8689 | perf_addr_filter_apply(filter, mm); | |
8690 | ||
8691 | count++; | |
8692 | } | |
8693 | ||
8694 | event->addr_filters_gen++; | |
8695 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8696 | ||
8697 | up_read(&mm->mmap_sem); | |
8698 | ||
8699 | mmput(mm); | |
8700 | ||
8701 | restart: | |
767ae086 | 8702 | perf_event_stop(event, 1); |
375637bc AS |
8703 | } |
8704 | ||
8705 | /* | |
8706 | * Address range filtering: limiting the data to certain | |
8707 | * instruction address ranges. Filters are ioctl()ed to us from | |
8708 | * userspace as ascii strings. | |
8709 | * | |
8710 | * Filter string format: | |
8711 | * | |
8712 | * ACTION RANGE_SPEC | |
8713 | * where ACTION is one of the | |
8714 | * * "filter": limit the trace to this region | |
8715 | * * "start": start tracing from this address | |
8716 | * * "stop": stop tracing at this address/region; | |
8717 | * RANGE_SPEC is | |
8718 | * * for kernel addresses: <start address>[/<size>] | |
8719 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8720 | * | |
8721 | * if <size> is not specified, the range is treated as a single address. | |
8722 | */ | |
8723 | enum { | |
e96271f3 | 8724 | IF_ACT_NONE = -1, |
375637bc AS |
8725 | IF_ACT_FILTER, |
8726 | IF_ACT_START, | |
8727 | IF_ACT_STOP, | |
8728 | IF_SRC_FILE, | |
8729 | IF_SRC_KERNEL, | |
8730 | IF_SRC_FILEADDR, | |
8731 | IF_SRC_KERNELADDR, | |
8732 | }; | |
8733 | ||
8734 | enum { | |
8735 | IF_STATE_ACTION = 0, | |
8736 | IF_STATE_SOURCE, | |
8737 | IF_STATE_END, | |
8738 | }; | |
8739 | ||
8740 | static const match_table_t if_tokens = { | |
8741 | { IF_ACT_FILTER, "filter" }, | |
8742 | { IF_ACT_START, "start" }, | |
8743 | { IF_ACT_STOP, "stop" }, | |
8744 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8745 | { IF_SRC_KERNEL, "%u/%u" }, | |
8746 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8747 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8748 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8749 | }; |
8750 | ||
8751 | /* | |
8752 | * Address filter string parser | |
8753 | */ | |
8754 | static int | |
8755 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8756 | struct list_head *filters) | |
8757 | { | |
8758 | struct perf_addr_filter *filter = NULL; | |
8759 | char *start, *orig, *filename = NULL; | |
8760 | struct path path; | |
8761 | substring_t args[MAX_OPT_ARGS]; | |
8762 | int state = IF_STATE_ACTION, token; | |
8763 | unsigned int kernel = 0; | |
8764 | int ret = -EINVAL; | |
8765 | ||
8766 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8767 | if (!fstr) | |
8768 | return -ENOMEM; | |
8769 | ||
8770 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8771 | ret = -EINVAL; | |
8772 | ||
8773 | if (!*start) | |
8774 | continue; | |
8775 | ||
8776 | /* filter definition begins */ | |
8777 | if (state == IF_STATE_ACTION) { | |
8778 | filter = perf_addr_filter_new(event, filters); | |
8779 | if (!filter) | |
8780 | goto fail; | |
8781 | } | |
8782 | ||
8783 | token = match_token(start, if_tokens, args); | |
8784 | switch (token) { | |
8785 | case IF_ACT_FILTER: | |
8786 | case IF_ACT_START: | |
8787 | filter->filter = 1; | |
8788 | ||
8789 | case IF_ACT_STOP: | |
8790 | if (state != IF_STATE_ACTION) | |
8791 | goto fail; | |
8792 | ||
8793 | state = IF_STATE_SOURCE; | |
8794 | break; | |
8795 | ||
8796 | case IF_SRC_KERNELADDR: | |
8797 | case IF_SRC_KERNEL: | |
8798 | kernel = 1; | |
8799 | ||
8800 | case IF_SRC_FILEADDR: | |
8801 | case IF_SRC_FILE: | |
8802 | if (state != IF_STATE_SOURCE) | |
8803 | goto fail; | |
8804 | ||
8805 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8806 | filter->range = 1; | |
8807 | ||
8808 | *args[0].to = 0; | |
8809 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8810 | if (ret) | |
8811 | goto fail; | |
8812 | ||
8813 | if (filter->range) { | |
8814 | *args[1].to = 0; | |
8815 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8816 | if (ret) | |
8817 | goto fail; | |
8818 | } | |
8819 | ||
4059ffd0 MP |
8820 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8821 | int fpos = filter->range ? 2 : 1; | |
8822 | ||
8823 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8824 | if (!filename) { |
8825 | ret = -ENOMEM; | |
8826 | goto fail; | |
8827 | } | |
8828 | } | |
8829 | ||
8830 | state = IF_STATE_END; | |
8831 | break; | |
8832 | ||
8833 | default: | |
8834 | goto fail; | |
8835 | } | |
8836 | ||
8837 | /* | |
8838 | * Filter definition is fully parsed, validate and install it. | |
8839 | * Make sure that it doesn't contradict itself or the event's | |
8840 | * attribute. | |
8841 | */ | |
8842 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 8843 | ret = -EINVAL; |
375637bc AS |
8844 | if (kernel && event->attr.exclude_kernel) |
8845 | goto fail; | |
8846 | ||
8847 | if (!kernel) { | |
8848 | if (!filename) | |
8849 | goto fail; | |
8850 | ||
6ce77bfd AS |
8851 | /* |
8852 | * For now, we only support file-based filters | |
8853 | * in per-task events; doing so for CPU-wide | |
8854 | * events requires additional context switching | |
8855 | * trickery, since same object code will be | |
8856 | * mapped at different virtual addresses in | |
8857 | * different processes. | |
8858 | */ | |
8859 | ret = -EOPNOTSUPP; | |
8860 | if (!event->ctx->task) | |
8861 | goto fail_free_name; | |
8862 | ||
375637bc AS |
8863 | /* look up the path and grab its inode */ |
8864 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8865 | if (ret) | |
8866 | goto fail_free_name; | |
8867 | ||
8868 | filter->inode = igrab(d_inode(path.dentry)); | |
8869 | path_put(&path); | |
8870 | kfree(filename); | |
8871 | filename = NULL; | |
8872 | ||
8873 | ret = -EINVAL; | |
8874 | if (!filter->inode || | |
8875 | !S_ISREG(filter->inode->i_mode)) | |
8876 | /* free_filters_list() will iput() */ | |
8877 | goto fail; | |
6ce77bfd AS |
8878 | |
8879 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
8880 | } |
8881 | ||
8882 | /* ready to consume more filters */ | |
8883 | state = IF_STATE_ACTION; | |
8884 | filter = NULL; | |
8885 | } | |
8886 | } | |
8887 | ||
8888 | if (state != IF_STATE_ACTION) | |
8889 | goto fail; | |
8890 | ||
8891 | kfree(orig); | |
8892 | ||
8893 | return 0; | |
8894 | ||
8895 | fail_free_name: | |
8896 | kfree(filename); | |
8897 | fail: | |
8898 | free_filters_list(filters); | |
8899 | kfree(orig); | |
8900 | ||
8901 | return ret; | |
8902 | } | |
8903 | ||
8904 | static int | |
8905 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8906 | { | |
8907 | LIST_HEAD(filters); | |
8908 | int ret; | |
8909 | ||
8910 | /* | |
8911 | * Since this is called in perf_ioctl() path, we're already holding | |
8912 | * ctx::mutex. | |
8913 | */ | |
8914 | lockdep_assert_held(&event->ctx->mutex); | |
8915 | ||
8916 | if (WARN_ON_ONCE(event->parent)) | |
8917 | return -EINVAL; | |
8918 | ||
375637bc AS |
8919 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
8920 | if (ret) | |
6ce77bfd | 8921 | goto fail_clear_files; |
375637bc AS |
8922 | |
8923 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
8924 | if (ret) |
8925 | goto fail_free_filters; | |
375637bc AS |
8926 | |
8927 | /* remove existing filters, if any */ | |
8928 | perf_addr_filters_splice(event, &filters); | |
8929 | ||
8930 | /* install new filters */ | |
8931 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8932 | ||
6ce77bfd AS |
8933 | return ret; |
8934 | ||
8935 | fail_free_filters: | |
8936 | free_filters_list(&filters); | |
8937 | ||
8938 | fail_clear_files: | |
8939 | event->addr_filters.nr_file_filters = 0; | |
8940 | ||
375637bc AS |
8941 | return ret; |
8942 | } | |
8943 | ||
c796bbbe AS |
8944 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8945 | { | |
c796bbbe | 8946 | int ret = -EINVAL; |
e12f03d7 | 8947 | char *filter_str; |
c796bbbe AS |
8948 | |
8949 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8950 | if (IS_ERR(filter_str)) | |
8951 | return PTR_ERR(filter_str); | |
8952 | ||
e12f03d7 SL |
8953 | #ifdef CONFIG_EVENT_TRACING |
8954 | if (perf_event_is_tracing(event)) { | |
8955 | struct perf_event_context *ctx = event->ctx; | |
8956 | ||
8957 | /* | |
8958 | * Beware, here be dragons!! | |
8959 | * | |
8960 | * the tracepoint muck will deadlock against ctx->mutex, but | |
8961 | * the tracepoint stuff does not actually need it. So | |
8962 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
8963 | * already have a reference on ctx. | |
8964 | * | |
8965 | * This can result in event getting moved to a different ctx, | |
8966 | * but that does not affect the tracepoint state. | |
8967 | */ | |
8968 | mutex_unlock(&ctx->mutex); | |
8969 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
8970 | mutex_lock(&ctx->mutex); | |
8971 | } else | |
8972 | #endif | |
8973 | if (has_addr_filter(event)) | |
375637bc | 8974 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
8975 | |
8976 | kfree(filter_str); | |
8977 | return ret; | |
8978 | } | |
8979 | ||
b0a873eb PZ |
8980 | /* |
8981 | * hrtimer based swevent callback | |
8982 | */ | |
f29ac756 | 8983 | |
b0a873eb | 8984 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8985 | { |
b0a873eb PZ |
8986 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8987 | struct perf_sample_data data; | |
8988 | struct pt_regs *regs; | |
8989 | struct perf_event *event; | |
8990 | u64 period; | |
f29ac756 | 8991 | |
b0a873eb | 8992 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8993 | |
8994 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8995 | return HRTIMER_NORESTART; | |
8996 | ||
b0a873eb | 8997 | event->pmu->read(event); |
f344011c | 8998 | |
fd0d000b | 8999 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9000 | regs = get_irq_regs(); |
9001 | ||
9002 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9003 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9004 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9005 | ret = HRTIMER_NORESTART; |
9006 | } | |
24f1e32c | 9007 | |
b0a873eb PZ |
9008 | period = max_t(u64, 10000, event->hw.sample_period); |
9009 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9010 | |
b0a873eb | 9011 | return ret; |
f29ac756 PZ |
9012 | } |
9013 | ||
b0a873eb | 9014 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9015 | { |
b0a873eb | 9016 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9017 | s64 period; |
9018 | ||
9019 | if (!is_sampling_event(event)) | |
9020 | return; | |
f5ffe02e | 9021 | |
5d508e82 FBH |
9022 | period = local64_read(&hwc->period_left); |
9023 | if (period) { | |
9024 | if (period < 0) | |
9025 | period = 10000; | |
fa407f35 | 9026 | |
5d508e82 FBH |
9027 | local64_set(&hwc->period_left, 0); |
9028 | } else { | |
9029 | period = max_t(u64, 10000, hwc->sample_period); | |
9030 | } | |
3497d206 TG |
9031 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
9032 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 9033 | } |
b0a873eb PZ |
9034 | |
9035 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9036 | { |
b0a873eb PZ |
9037 | struct hw_perf_event *hwc = &event->hw; |
9038 | ||
6c7e550f | 9039 | if (is_sampling_event(event)) { |
b0a873eb | 9040 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9041 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9042 | |
9043 | hrtimer_cancel(&hwc->hrtimer); | |
9044 | } | |
24f1e32c FW |
9045 | } |
9046 | ||
ba3dd36c PZ |
9047 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9048 | { | |
9049 | struct hw_perf_event *hwc = &event->hw; | |
9050 | ||
9051 | if (!is_sampling_event(event)) | |
9052 | return; | |
9053 | ||
9054 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
9055 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
9056 | ||
9057 | /* | |
9058 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9059 | * mapping and avoid the whole period adjust feedback stuff. | |
9060 | */ | |
9061 | if (event->attr.freq) { | |
9062 | long freq = event->attr.sample_freq; | |
9063 | ||
9064 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9065 | hwc->sample_period = event->attr.sample_period; | |
9066 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9067 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9068 | event->attr.freq = 0; |
9069 | } | |
9070 | } | |
9071 | ||
b0a873eb PZ |
9072 | /* |
9073 | * Software event: cpu wall time clock | |
9074 | */ | |
9075 | ||
9076 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9077 | { |
b0a873eb PZ |
9078 | s64 prev; |
9079 | u64 now; | |
9080 | ||
a4eaf7f1 | 9081 | now = local_clock(); |
b0a873eb PZ |
9082 | prev = local64_xchg(&event->hw.prev_count, now); |
9083 | local64_add(now - prev, &event->count); | |
24f1e32c | 9084 | } |
24f1e32c | 9085 | |
a4eaf7f1 | 9086 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9087 | { |
a4eaf7f1 | 9088 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9089 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9090 | } |
9091 | ||
a4eaf7f1 | 9092 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9093 | { |
b0a873eb PZ |
9094 | perf_swevent_cancel_hrtimer(event); |
9095 | cpu_clock_event_update(event); | |
9096 | } | |
f29ac756 | 9097 | |
a4eaf7f1 PZ |
9098 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9099 | { | |
9100 | if (flags & PERF_EF_START) | |
9101 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9102 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9103 | |
9104 | return 0; | |
9105 | } | |
9106 | ||
9107 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9108 | { | |
9109 | cpu_clock_event_stop(event, flags); | |
9110 | } | |
9111 | ||
b0a873eb PZ |
9112 | static void cpu_clock_event_read(struct perf_event *event) |
9113 | { | |
9114 | cpu_clock_event_update(event); | |
9115 | } | |
f344011c | 9116 | |
b0a873eb PZ |
9117 | static int cpu_clock_event_init(struct perf_event *event) |
9118 | { | |
9119 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9120 | return -ENOENT; | |
9121 | ||
9122 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9123 | return -ENOENT; | |
9124 | ||
2481c5fa SE |
9125 | /* |
9126 | * no branch sampling for software events | |
9127 | */ | |
9128 | if (has_branch_stack(event)) | |
9129 | return -EOPNOTSUPP; | |
9130 | ||
ba3dd36c PZ |
9131 | perf_swevent_init_hrtimer(event); |
9132 | ||
b0a873eb | 9133 | return 0; |
f29ac756 PZ |
9134 | } |
9135 | ||
b0a873eb | 9136 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9137 | .task_ctx_nr = perf_sw_context, |
9138 | ||
34f43927 PZ |
9139 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9140 | ||
b0a873eb | 9141 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9142 | .add = cpu_clock_event_add, |
9143 | .del = cpu_clock_event_del, | |
9144 | .start = cpu_clock_event_start, | |
9145 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9146 | .read = cpu_clock_event_read, |
9147 | }; | |
9148 | ||
9149 | /* | |
9150 | * Software event: task time clock | |
9151 | */ | |
9152 | ||
9153 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9154 | { |
b0a873eb PZ |
9155 | u64 prev; |
9156 | s64 delta; | |
5c92d124 | 9157 | |
b0a873eb PZ |
9158 | prev = local64_xchg(&event->hw.prev_count, now); |
9159 | delta = now - prev; | |
9160 | local64_add(delta, &event->count); | |
9161 | } | |
5c92d124 | 9162 | |
a4eaf7f1 | 9163 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9164 | { |
a4eaf7f1 | 9165 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9166 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9167 | } |
9168 | ||
a4eaf7f1 | 9169 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9170 | { |
9171 | perf_swevent_cancel_hrtimer(event); | |
9172 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9173 | } |
9174 | ||
9175 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9176 | { | |
9177 | if (flags & PERF_EF_START) | |
9178 | task_clock_event_start(event, flags); | |
6a694a60 | 9179 | perf_event_update_userpage(event); |
b0a873eb | 9180 | |
a4eaf7f1 PZ |
9181 | return 0; |
9182 | } | |
9183 | ||
9184 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9185 | { | |
9186 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9187 | } |
9188 | ||
9189 | static void task_clock_event_read(struct perf_event *event) | |
9190 | { | |
768a06e2 PZ |
9191 | u64 now = perf_clock(); |
9192 | u64 delta = now - event->ctx->timestamp; | |
9193 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
9194 | |
9195 | task_clock_event_update(event, time); | |
9196 | } | |
9197 | ||
9198 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 9199 | { |
b0a873eb PZ |
9200 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
9201 | return -ENOENT; | |
9202 | ||
9203 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
9204 | return -ENOENT; | |
9205 | ||
2481c5fa SE |
9206 | /* |
9207 | * no branch sampling for software events | |
9208 | */ | |
9209 | if (has_branch_stack(event)) | |
9210 | return -EOPNOTSUPP; | |
9211 | ||
ba3dd36c PZ |
9212 | perf_swevent_init_hrtimer(event); |
9213 | ||
b0a873eb | 9214 | return 0; |
6fb2915d LZ |
9215 | } |
9216 | ||
b0a873eb | 9217 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
9218 | .task_ctx_nr = perf_sw_context, |
9219 | ||
34f43927 PZ |
9220 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9221 | ||
b0a873eb | 9222 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
9223 | .add = task_clock_event_add, |
9224 | .del = task_clock_event_del, | |
9225 | .start = task_clock_event_start, | |
9226 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
9227 | .read = task_clock_event_read, |
9228 | }; | |
6fb2915d | 9229 | |
ad5133b7 | 9230 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 9231 | { |
e077df4f | 9232 | } |
6fb2915d | 9233 | |
fbbe0701 SB |
9234 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
9235 | { | |
9236 | } | |
9237 | ||
ad5133b7 | 9238 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 9239 | { |
ad5133b7 | 9240 | return 0; |
6fb2915d LZ |
9241 | } |
9242 | ||
18ab2cd3 | 9243 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
9244 | |
9245 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 9246 | { |
fbbe0701 SB |
9247 | __this_cpu_write(nop_txn_flags, flags); |
9248 | ||
9249 | if (flags & ~PERF_PMU_TXN_ADD) | |
9250 | return; | |
9251 | ||
ad5133b7 | 9252 | perf_pmu_disable(pmu); |
6fb2915d LZ |
9253 | } |
9254 | ||
ad5133b7 PZ |
9255 | static int perf_pmu_commit_txn(struct pmu *pmu) |
9256 | { | |
fbbe0701 SB |
9257 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9258 | ||
9259 | __this_cpu_write(nop_txn_flags, 0); | |
9260 | ||
9261 | if (flags & ~PERF_PMU_TXN_ADD) | |
9262 | return 0; | |
9263 | ||
ad5133b7 PZ |
9264 | perf_pmu_enable(pmu); |
9265 | return 0; | |
9266 | } | |
e077df4f | 9267 | |
ad5133b7 | 9268 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 9269 | { |
fbbe0701 SB |
9270 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9271 | ||
9272 | __this_cpu_write(nop_txn_flags, 0); | |
9273 | ||
9274 | if (flags & ~PERF_PMU_TXN_ADD) | |
9275 | return; | |
9276 | ||
ad5133b7 | 9277 | perf_pmu_enable(pmu); |
24f1e32c FW |
9278 | } |
9279 | ||
35edc2a5 PZ |
9280 | static int perf_event_idx_default(struct perf_event *event) |
9281 | { | |
c719f560 | 9282 | return 0; |
35edc2a5 PZ |
9283 | } |
9284 | ||
8dc85d54 PZ |
9285 | /* |
9286 | * Ensures all contexts with the same task_ctx_nr have the same | |
9287 | * pmu_cpu_context too. | |
9288 | */ | |
9e317041 | 9289 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 9290 | { |
8dc85d54 | 9291 | struct pmu *pmu; |
b326e956 | 9292 | |
8dc85d54 PZ |
9293 | if (ctxn < 0) |
9294 | return NULL; | |
24f1e32c | 9295 | |
8dc85d54 PZ |
9296 | list_for_each_entry(pmu, &pmus, entry) { |
9297 | if (pmu->task_ctx_nr == ctxn) | |
9298 | return pmu->pmu_cpu_context; | |
9299 | } | |
24f1e32c | 9300 | |
8dc85d54 | 9301 | return NULL; |
24f1e32c FW |
9302 | } |
9303 | ||
51676957 PZ |
9304 | static void free_pmu_context(struct pmu *pmu) |
9305 | { | |
df0062b2 WD |
9306 | /* |
9307 | * Static contexts such as perf_sw_context have a global lifetime | |
9308 | * and may be shared between different PMUs. Avoid freeing them | |
9309 | * when a single PMU is going away. | |
9310 | */ | |
9311 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9312 | return; | |
9313 | ||
8dc85d54 | 9314 | mutex_lock(&pmus_lock); |
51676957 | 9315 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 | 9316 | mutex_unlock(&pmus_lock); |
24f1e32c | 9317 | } |
6e855cd4 AS |
9318 | |
9319 | /* | |
9320 | * Let userspace know that this PMU supports address range filtering: | |
9321 | */ | |
9322 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9323 | struct device_attribute *attr, | |
9324 | char *page) | |
9325 | { | |
9326 | struct pmu *pmu = dev_get_drvdata(dev); | |
9327 | ||
9328 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9329 | } | |
9330 | DEVICE_ATTR_RO(nr_addr_filters); | |
9331 | ||
2e80a82a | 9332 | static struct idr pmu_idr; |
d6d020e9 | 9333 | |
abe43400 PZ |
9334 | static ssize_t |
9335 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9336 | { | |
9337 | struct pmu *pmu = dev_get_drvdata(dev); | |
9338 | ||
9339 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9340 | } | |
90826ca7 | 9341 | static DEVICE_ATTR_RO(type); |
abe43400 | 9342 | |
62b85639 SE |
9343 | static ssize_t |
9344 | perf_event_mux_interval_ms_show(struct device *dev, | |
9345 | struct device_attribute *attr, | |
9346 | char *page) | |
9347 | { | |
9348 | struct pmu *pmu = dev_get_drvdata(dev); | |
9349 | ||
9350 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9351 | } | |
9352 | ||
272325c4 PZ |
9353 | static DEFINE_MUTEX(mux_interval_mutex); |
9354 | ||
62b85639 SE |
9355 | static ssize_t |
9356 | perf_event_mux_interval_ms_store(struct device *dev, | |
9357 | struct device_attribute *attr, | |
9358 | const char *buf, size_t count) | |
9359 | { | |
9360 | struct pmu *pmu = dev_get_drvdata(dev); | |
9361 | int timer, cpu, ret; | |
9362 | ||
9363 | ret = kstrtoint(buf, 0, &timer); | |
9364 | if (ret) | |
9365 | return ret; | |
9366 | ||
9367 | if (timer < 1) | |
9368 | return -EINVAL; | |
9369 | ||
9370 | /* same value, noting to do */ | |
9371 | if (timer == pmu->hrtimer_interval_ms) | |
9372 | return count; | |
9373 | ||
272325c4 | 9374 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9375 | pmu->hrtimer_interval_ms = timer; |
9376 | ||
9377 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9378 | cpus_read_lock(); |
272325c4 | 9379 | for_each_online_cpu(cpu) { |
62b85639 SE |
9380 | struct perf_cpu_context *cpuctx; |
9381 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
9382 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9383 | ||
272325c4 PZ |
9384 | cpu_function_call(cpu, |
9385 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 9386 | } |
a63fbed7 | 9387 | cpus_read_unlock(); |
272325c4 | 9388 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
9389 | |
9390 | return count; | |
9391 | } | |
90826ca7 | 9392 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 9393 | |
90826ca7 GKH |
9394 | static struct attribute *pmu_dev_attrs[] = { |
9395 | &dev_attr_type.attr, | |
9396 | &dev_attr_perf_event_mux_interval_ms.attr, | |
9397 | NULL, | |
abe43400 | 9398 | }; |
90826ca7 | 9399 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
9400 | |
9401 | static int pmu_bus_running; | |
9402 | static struct bus_type pmu_bus = { | |
9403 | .name = "event_source", | |
90826ca7 | 9404 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
9405 | }; |
9406 | ||
9407 | static void pmu_dev_release(struct device *dev) | |
9408 | { | |
9409 | kfree(dev); | |
9410 | } | |
9411 | ||
9412 | static int pmu_dev_alloc(struct pmu *pmu) | |
9413 | { | |
9414 | int ret = -ENOMEM; | |
9415 | ||
9416 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
9417 | if (!pmu->dev) | |
9418 | goto out; | |
9419 | ||
0c9d42ed | 9420 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
9421 | device_initialize(pmu->dev); |
9422 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
9423 | if (ret) | |
9424 | goto free_dev; | |
9425 | ||
9426 | dev_set_drvdata(pmu->dev, pmu); | |
9427 | pmu->dev->bus = &pmu_bus; | |
9428 | pmu->dev->release = pmu_dev_release; | |
9429 | ret = device_add(pmu->dev); | |
9430 | if (ret) | |
9431 | goto free_dev; | |
9432 | ||
6e855cd4 AS |
9433 | /* For PMUs with address filters, throw in an extra attribute: */ |
9434 | if (pmu->nr_addr_filters) | |
9435 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9436 | ||
9437 | if (ret) | |
9438 | goto del_dev; | |
9439 | ||
abe43400 PZ |
9440 | out: |
9441 | return ret; | |
9442 | ||
6e855cd4 AS |
9443 | del_dev: |
9444 | device_del(pmu->dev); | |
9445 | ||
abe43400 PZ |
9446 | free_dev: |
9447 | put_device(pmu->dev); | |
9448 | goto out; | |
9449 | } | |
9450 | ||
547e9fd7 | 9451 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 9452 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 9453 | |
03d8e80b | 9454 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 9455 | { |
108b02cf | 9456 | int cpu, ret; |
24f1e32c | 9457 | |
b0a873eb | 9458 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
9459 | ret = -ENOMEM; |
9460 | pmu->pmu_disable_count = alloc_percpu(int); | |
9461 | if (!pmu->pmu_disable_count) | |
9462 | goto unlock; | |
f29ac756 | 9463 | |
2e80a82a PZ |
9464 | pmu->type = -1; |
9465 | if (!name) | |
9466 | goto skip_type; | |
9467 | pmu->name = name; | |
9468 | ||
9469 | if (type < 0) { | |
0e9c3be2 TH |
9470 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
9471 | if (type < 0) { | |
9472 | ret = type; | |
2e80a82a PZ |
9473 | goto free_pdc; |
9474 | } | |
9475 | } | |
9476 | pmu->type = type; | |
9477 | ||
abe43400 PZ |
9478 | if (pmu_bus_running) { |
9479 | ret = pmu_dev_alloc(pmu); | |
9480 | if (ret) | |
9481 | goto free_idr; | |
9482 | } | |
9483 | ||
2e80a82a | 9484 | skip_type: |
26657848 PZ |
9485 | if (pmu->task_ctx_nr == perf_hw_context) { |
9486 | static int hw_context_taken = 0; | |
9487 | ||
5101ef20 MR |
9488 | /* |
9489 | * Other than systems with heterogeneous CPUs, it never makes | |
9490 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
9491 | * uncore must use perf_invalid_context. | |
9492 | */ | |
9493 | if (WARN_ON_ONCE(hw_context_taken && | |
9494 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
9495 | pmu->task_ctx_nr = perf_invalid_context; |
9496 | ||
9497 | hw_context_taken = 1; | |
9498 | } | |
9499 | ||
8dc85d54 PZ |
9500 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
9501 | if (pmu->pmu_cpu_context) | |
9502 | goto got_cpu_context; | |
f29ac756 | 9503 | |
c4814202 | 9504 | ret = -ENOMEM; |
108b02cf PZ |
9505 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
9506 | if (!pmu->pmu_cpu_context) | |
abe43400 | 9507 | goto free_dev; |
f344011c | 9508 | |
108b02cf PZ |
9509 | for_each_possible_cpu(cpu) { |
9510 | struct perf_cpu_context *cpuctx; | |
9511 | ||
9512 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 9513 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 9514 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 9515 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 9516 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 9517 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 9518 | |
272325c4 | 9519 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 9520 | } |
76e1d904 | 9521 | |
8dc85d54 | 9522 | got_cpu_context: |
ad5133b7 PZ |
9523 | if (!pmu->start_txn) { |
9524 | if (pmu->pmu_enable) { | |
9525 | /* | |
9526 | * If we have pmu_enable/pmu_disable calls, install | |
9527 | * transaction stubs that use that to try and batch | |
9528 | * hardware accesses. | |
9529 | */ | |
9530 | pmu->start_txn = perf_pmu_start_txn; | |
9531 | pmu->commit_txn = perf_pmu_commit_txn; | |
9532 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
9533 | } else { | |
fbbe0701 | 9534 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
9535 | pmu->commit_txn = perf_pmu_nop_int; |
9536 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 9537 | } |
5c92d124 | 9538 | } |
15dbf27c | 9539 | |
ad5133b7 PZ |
9540 | if (!pmu->pmu_enable) { |
9541 | pmu->pmu_enable = perf_pmu_nop_void; | |
9542 | pmu->pmu_disable = perf_pmu_nop_void; | |
9543 | } | |
9544 | ||
35edc2a5 PZ |
9545 | if (!pmu->event_idx) |
9546 | pmu->event_idx = perf_event_idx_default; | |
9547 | ||
b0a873eb | 9548 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 9549 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
9550 | ret = 0; |
9551 | unlock: | |
b0a873eb PZ |
9552 | mutex_unlock(&pmus_lock); |
9553 | ||
33696fc0 | 9554 | return ret; |
108b02cf | 9555 | |
abe43400 PZ |
9556 | free_dev: |
9557 | device_del(pmu->dev); | |
9558 | put_device(pmu->dev); | |
9559 | ||
2e80a82a PZ |
9560 | free_idr: |
9561 | if (pmu->type >= PERF_TYPE_MAX) | |
9562 | idr_remove(&pmu_idr, pmu->type); | |
9563 | ||
108b02cf PZ |
9564 | free_pdc: |
9565 | free_percpu(pmu->pmu_disable_count); | |
9566 | goto unlock; | |
f29ac756 | 9567 | } |
c464c76e | 9568 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 9569 | |
b0a873eb | 9570 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 9571 | { |
0933840a JO |
9572 | int remove_device; |
9573 | ||
b0a873eb | 9574 | mutex_lock(&pmus_lock); |
0933840a | 9575 | remove_device = pmu_bus_running; |
b0a873eb PZ |
9576 | list_del_rcu(&pmu->entry); |
9577 | mutex_unlock(&pmus_lock); | |
5c92d124 | 9578 | |
0475f9ea | 9579 | /* |
cde8e884 PZ |
9580 | * We dereference the pmu list under both SRCU and regular RCU, so |
9581 | * synchronize against both of those. | |
0475f9ea | 9582 | */ |
b0a873eb | 9583 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 9584 | synchronize_rcu(); |
d6d020e9 | 9585 | |
33696fc0 | 9586 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
9587 | if (pmu->type >= PERF_TYPE_MAX) |
9588 | idr_remove(&pmu_idr, pmu->type); | |
0933840a JO |
9589 | if (remove_device) { |
9590 | if (pmu->nr_addr_filters) | |
9591 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9592 | device_del(pmu->dev); | |
9593 | put_device(pmu->dev); | |
9594 | } | |
51676957 | 9595 | free_pmu_context(pmu); |
b0a873eb | 9596 | } |
c464c76e | 9597 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 9598 | |
cc34b98b MR |
9599 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
9600 | { | |
ccd41c86 | 9601 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
9602 | int ret; |
9603 | ||
9604 | if (!try_module_get(pmu->module)) | |
9605 | return -ENODEV; | |
ccd41c86 | 9606 | |
0c7296ca PZ |
9607 | /* |
9608 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
9609 | * for example, validate if the group fits on the PMU. Therefore, | |
9610 | * if this is a sibling event, acquire the ctx->mutex to protect | |
9611 | * the sibling_list. | |
9612 | */ | |
9613 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
9614 | /* |
9615 | * This ctx->mutex can nest when we're called through | |
9616 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
9617 | */ | |
9618 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
9619 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
9620 | BUG_ON(!ctx); |
9621 | } | |
9622 | ||
cc34b98b MR |
9623 | event->pmu = pmu; |
9624 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
9625 | |
9626 | if (ctx) | |
9627 | perf_event_ctx_unlock(event->group_leader, ctx); | |
9628 | ||
cc34b98b MR |
9629 | if (ret) |
9630 | module_put(pmu->module); | |
9631 | ||
9632 | return ret; | |
9633 | } | |
9634 | ||
18ab2cd3 | 9635 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 9636 | { |
85c617ab | 9637 | struct pmu *pmu; |
b0a873eb | 9638 | int idx; |
940c5b29 | 9639 | int ret; |
b0a873eb PZ |
9640 | |
9641 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 9642 | |
40999312 KL |
9643 | /* Try parent's PMU first: */ |
9644 | if (event->parent && event->parent->pmu) { | |
9645 | pmu = event->parent->pmu; | |
9646 | ret = perf_try_init_event(pmu, event); | |
9647 | if (!ret) | |
9648 | goto unlock; | |
9649 | } | |
9650 | ||
2e80a82a PZ |
9651 | rcu_read_lock(); |
9652 | pmu = idr_find(&pmu_idr, event->attr.type); | |
9653 | rcu_read_unlock(); | |
940c5b29 | 9654 | if (pmu) { |
cc34b98b | 9655 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
9656 | if (ret) |
9657 | pmu = ERR_PTR(ret); | |
2e80a82a | 9658 | goto unlock; |
940c5b29 | 9659 | } |
2e80a82a | 9660 | |
b0a873eb | 9661 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 9662 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 9663 | if (!ret) |
e5f4d339 | 9664 | goto unlock; |
76e1d904 | 9665 | |
b0a873eb PZ |
9666 | if (ret != -ENOENT) { |
9667 | pmu = ERR_PTR(ret); | |
e5f4d339 | 9668 | goto unlock; |
f344011c | 9669 | } |
5c92d124 | 9670 | } |
e5f4d339 PZ |
9671 | pmu = ERR_PTR(-ENOENT); |
9672 | unlock: | |
b0a873eb | 9673 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 9674 | |
4aeb0b42 | 9675 | return pmu; |
5c92d124 IM |
9676 | } |
9677 | ||
f2fb6bef KL |
9678 | static void attach_sb_event(struct perf_event *event) |
9679 | { | |
9680 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
9681 | ||
9682 | raw_spin_lock(&pel->lock); | |
9683 | list_add_rcu(&event->sb_list, &pel->list); | |
9684 | raw_spin_unlock(&pel->lock); | |
9685 | } | |
9686 | ||
aab5b71e PZ |
9687 | /* |
9688 | * We keep a list of all !task (and therefore per-cpu) events | |
9689 | * that need to receive side-band records. | |
9690 | * | |
9691 | * This avoids having to scan all the various PMU per-cpu contexts | |
9692 | * looking for them. | |
9693 | */ | |
f2fb6bef KL |
9694 | static void account_pmu_sb_event(struct perf_event *event) |
9695 | { | |
a4f144eb | 9696 | if (is_sb_event(event)) |
f2fb6bef KL |
9697 | attach_sb_event(event); |
9698 | } | |
9699 | ||
4beb31f3 FW |
9700 | static void account_event_cpu(struct perf_event *event, int cpu) |
9701 | { | |
9702 | if (event->parent) | |
9703 | return; | |
9704 | ||
4beb31f3 FW |
9705 | if (is_cgroup_event(event)) |
9706 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9707 | } | |
9708 | ||
555e0c1e FW |
9709 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9710 | static void account_freq_event_nohz(void) | |
9711 | { | |
9712 | #ifdef CONFIG_NO_HZ_FULL | |
9713 | /* Lock so we don't race with concurrent unaccount */ | |
9714 | spin_lock(&nr_freq_lock); | |
9715 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9716 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9717 | spin_unlock(&nr_freq_lock); | |
9718 | #endif | |
9719 | } | |
9720 | ||
9721 | static void account_freq_event(void) | |
9722 | { | |
9723 | if (tick_nohz_full_enabled()) | |
9724 | account_freq_event_nohz(); | |
9725 | else | |
9726 | atomic_inc(&nr_freq_events); | |
9727 | } | |
9728 | ||
9729 | ||
766d6c07 FW |
9730 | static void account_event(struct perf_event *event) |
9731 | { | |
25432ae9 PZ |
9732 | bool inc = false; |
9733 | ||
4beb31f3 FW |
9734 | if (event->parent) |
9735 | return; | |
9736 | ||
766d6c07 | 9737 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9738 | inc = true; |
766d6c07 FW |
9739 | if (event->attr.mmap || event->attr.mmap_data) |
9740 | atomic_inc(&nr_mmap_events); | |
9741 | if (event->attr.comm) | |
9742 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
9743 | if (event->attr.namespaces) |
9744 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
9745 | if (event->attr.task) |
9746 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9747 | if (event->attr.freq) |
9748 | account_freq_event(); | |
45ac1403 AH |
9749 | if (event->attr.context_switch) { |
9750 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9751 | inc = true; |
45ac1403 | 9752 | } |
4beb31f3 | 9753 | if (has_branch_stack(event)) |
25432ae9 | 9754 | inc = true; |
4beb31f3 | 9755 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9756 | inc = true; |
9757 | ||
9107c89e | 9758 | if (inc) { |
5bce9db1 AS |
9759 | /* |
9760 | * We need the mutex here because static_branch_enable() | |
9761 | * must complete *before* the perf_sched_count increment | |
9762 | * becomes visible. | |
9763 | */ | |
9107c89e PZ |
9764 | if (atomic_inc_not_zero(&perf_sched_count)) |
9765 | goto enabled; | |
9766 | ||
9767 | mutex_lock(&perf_sched_mutex); | |
9768 | if (!atomic_read(&perf_sched_count)) { | |
9769 | static_branch_enable(&perf_sched_events); | |
9770 | /* | |
9771 | * Guarantee that all CPUs observe they key change and | |
9772 | * call the perf scheduling hooks before proceeding to | |
9773 | * install events that need them. | |
9774 | */ | |
9775 | synchronize_sched(); | |
9776 | } | |
9777 | /* | |
9778 | * Now that we have waited for the sync_sched(), allow further | |
9779 | * increments to by-pass the mutex. | |
9780 | */ | |
9781 | atomic_inc(&perf_sched_count); | |
9782 | mutex_unlock(&perf_sched_mutex); | |
9783 | } | |
9784 | enabled: | |
4beb31f3 FW |
9785 | |
9786 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9787 | |
9788 | account_pmu_sb_event(event); | |
766d6c07 FW |
9789 | } |
9790 | ||
0793a61d | 9791 | /* |
cdd6c482 | 9792 | * Allocate and initialize a event structure |
0793a61d | 9793 | */ |
cdd6c482 | 9794 | static struct perf_event * |
c3f00c70 | 9795 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9796 | struct task_struct *task, |
9797 | struct perf_event *group_leader, | |
9798 | struct perf_event *parent_event, | |
4dc0da86 | 9799 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9800 | void *context, int cgroup_fd) |
0793a61d | 9801 | { |
51b0fe39 | 9802 | struct pmu *pmu; |
cdd6c482 IM |
9803 | struct perf_event *event; |
9804 | struct hw_perf_event *hwc; | |
90983b16 | 9805 | long err = -EINVAL; |
0793a61d | 9806 | |
66832eb4 ON |
9807 | if ((unsigned)cpu >= nr_cpu_ids) { |
9808 | if (!task || cpu != -1) | |
9809 | return ERR_PTR(-EINVAL); | |
9810 | } | |
9811 | ||
c3f00c70 | 9812 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9813 | if (!event) |
d5d2bc0d | 9814 | return ERR_PTR(-ENOMEM); |
0793a61d | 9815 | |
04289bb9 | 9816 | /* |
cdd6c482 | 9817 | * Single events are their own group leaders, with an |
04289bb9 IM |
9818 | * empty sibling list: |
9819 | */ | |
9820 | if (!group_leader) | |
cdd6c482 | 9821 | group_leader = event; |
04289bb9 | 9822 | |
cdd6c482 IM |
9823 | mutex_init(&event->child_mutex); |
9824 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9825 | |
cdd6c482 IM |
9826 | INIT_LIST_HEAD(&event->event_entry); |
9827 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 9828 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 9829 | init_event_group(event); |
10c6db11 | 9830 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9831 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9832 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9833 | INIT_HLIST_NODE(&event->hlist_entry); |
9834 | ||
10c6db11 | 9835 | |
cdd6c482 | 9836 | init_waitqueue_head(&event->waitq); |
e360adbe | 9837 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9838 | |
cdd6c482 | 9839 | mutex_init(&event->mmap_mutex); |
375637bc | 9840 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9841 | |
a6fa941d | 9842 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9843 | event->cpu = cpu; |
9844 | event->attr = *attr; | |
9845 | event->group_leader = group_leader; | |
9846 | event->pmu = NULL; | |
cdd6c482 | 9847 | event->oncpu = -1; |
a96bbc16 | 9848 | |
cdd6c482 | 9849 | event->parent = parent_event; |
b84fbc9f | 9850 | |
17cf22c3 | 9851 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9852 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9853 | |
cdd6c482 | 9854 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9855 | |
d580ff86 PZ |
9856 | if (task) { |
9857 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9858 | /* |
50f16a8b PZ |
9859 | * XXX pmu::event_init needs to know what task to account to |
9860 | * and we cannot use the ctx information because we need the | |
9861 | * pmu before we get a ctx. | |
d580ff86 | 9862 | */ |
50f16a8b | 9863 | event->hw.target = task; |
d580ff86 PZ |
9864 | } |
9865 | ||
34f43927 PZ |
9866 | event->clock = &local_clock; |
9867 | if (parent_event) | |
9868 | event->clock = parent_event->clock; | |
9869 | ||
4dc0da86 | 9870 | if (!overflow_handler && parent_event) { |
b326e956 | 9871 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9872 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9873 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9874 | if (overflow_handler == bpf_overflow_handler) { |
9875 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9876 | ||
9877 | if (IS_ERR(prog)) { | |
9878 | err = PTR_ERR(prog); | |
9879 | goto err_ns; | |
9880 | } | |
9881 | event->prog = prog; | |
9882 | event->orig_overflow_handler = | |
9883 | parent_event->orig_overflow_handler; | |
9884 | } | |
9885 | #endif | |
4dc0da86 | 9886 | } |
66832eb4 | 9887 | |
1879445d WN |
9888 | if (overflow_handler) { |
9889 | event->overflow_handler = overflow_handler; | |
9890 | event->overflow_handler_context = context; | |
9ecda41a WN |
9891 | } else if (is_write_backward(event)){ |
9892 | event->overflow_handler = perf_event_output_backward; | |
9893 | event->overflow_handler_context = NULL; | |
1879445d | 9894 | } else { |
9ecda41a | 9895 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9896 | event->overflow_handler_context = NULL; |
9897 | } | |
97eaf530 | 9898 | |
0231bb53 | 9899 | perf_event__state_init(event); |
a86ed508 | 9900 | |
4aeb0b42 | 9901 | pmu = NULL; |
b8e83514 | 9902 | |
cdd6c482 | 9903 | hwc = &event->hw; |
bd2b5b12 | 9904 | hwc->sample_period = attr->sample_period; |
0d48696f | 9905 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9906 | hwc->sample_period = 1; |
eced1dfc | 9907 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9908 | |
e7850595 | 9909 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9910 | |
2023b359 | 9911 | /* |
ba5213ae PZ |
9912 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
9913 | * See perf_output_read(). | |
2023b359 | 9914 | */ |
ba5213ae | 9915 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 9916 | goto err_ns; |
a46a2300 YZ |
9917 | |
9918 | if (!has_branch_stack(event)) | |
9919 | event->attr.branch_sample_type = 0; | |
2023b359 | 9920 | |
79dff51e MF |
9921 | if (cgroup_fd != -1) { |
9922 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9923 | if (err) | |
9924 | goto err_ns; | |
9925 | } | |
9926 | ||
b0a873eb | 9927 | pmu = perf_init_event(event); |
85c617ab | 9928 | if (IS_ERR(pmu)) { |
4aeb0b42 | 9929 | err = PTR_ERR(pmu); |
90983b16 | 9930 | goto err_ns; |
621a01ea | 9931 | } |
d5d2bc0d | 9932 | |
bed5b25a AS |
9933 | err = exclusive_event_init(event); |
9934 | if (err) | |
9935 | goto err_pmu; | |
9936 | ||
375637bc AS |
9937 | if (has_addr_filter(event)) { |
9938 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9939 | sizeof(unsigned long), | |
9940 | GFP_KERNEL); | |
36cc2b92 DC |
9941 | if (!event->addr_filters_offs) { |
9942 | err = -ENOMEM; | |
375637bc | 9943 | goto err_per_task; |
36cc2b92 | 9944 | } |
375637bc AS |
9945 | |
9946 | /* force hw sync on the address filters */ | |
9947 | event->addr_filters_gen = 1; | |
9948 | } | |
9949 | ||
cdd6c482 | 9950 | if (!event->parent) { |
927c7a9e | 9951 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9952 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9953 | if (err) |
375637bc | 9954 | goto err_addr_filters; |
d010b332 | 9955 | } |
f344011c | 9956 | } |
9ee318a7 | 9957 | |
927a5570 AS |
9958 | /* symmetric to unaccount_event() in _free_event() */ |
9959 | account_event(event); | |
9960 | ||
cdd6c482 | 9961 | return event; |
90983b16 | 9962 | |
375637bc AS |
9963 | err_addr_filters: |
9964 | kfree(event->addr_filters_offs); | |
9965 | ||
bed5b25a AS |
9966 | err_per_task: |
9967 | exclusive_event_destroy(event); | |
9968 | ||
90983b16 FW |
9969 | err_pmu: |
9970 | if (event->destroy) | |
9971 | event->destroy(event); | |
c464c76e | 9972 | module_put(pmu->module); |
90983b16 | 9973 | err_ns: |
79dff51e MF |
9974 | if (is_cgroup_event(event)) |
9975 | perf_detach_cgroup(event); | |
90983b16 FW |
9976 | if (event->ns) |
9977 | put_pid_ns(event->ns); | |
9978 | kfree(event); | |
9979 | ||
9980 | return ERR_PTR(err); | |
0793a61d TG |
9981 | } |
9982 | ||
cdd6c482 IM |
9983 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9984 | struct perf_event_attr *attr) | |
974802ea | 9985 | { |
974802ea | 9986 | u32 size; |
cdf8073d | 9987 | int ret; |
974802ea PZ |
9988 | |
9989 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9990 | return -EFAULT; | |
9991 | ||
9992 | /* | |
9993 | * zero the full structure, so that a short copy will be nice. | |
9994 | */ | |
9995 | memset(attr, 0, sizeof(*attr)); | |
9996 | ||
9997 | ret = get_user(size, &uattr->size); | |
9998 | if (ret) | |
9999 | return ret; | |
10000 | ||
10001 | if (size > PAGE_SIZE) /* silly large */ | |
10002 | goto err_size; | |
10003 | ||
10004 | if (!size) /* abi compat */ | |
10005 | size = PERF_ATTR_SIZE_VER0; | |
10006 | ||
10007 | if (size < PERF_ATTR_SIZE_VER0) | |
10008 | goto err_size; | |
10009 | ||
10010 | /* | |
10011 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
10012 | * ensure all the unknown bits are 0 - i.e. new |
10013 | * user-space does not rely on any kernel feature | |
10014 | * extensions we dont know about yet. | |
974802ea PZ |
10015 | */ |
10016 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
10017 | unsigned char __user *addr; |
10018 | unsigned char __user *end; | |
10019 | unsigned char val; | |
974802ea | 10020 | |
cdf8073d IS |
10021 | addr = (void __user *)uattr + sizeof(*attr); |
10022 | end = (void __user *)uattr + size; | |
974802ea | 10023 | |
cdf8073d | 10024 | for (; addr < end; addr++) { |
974802ea PZ |
10025 | ret = get_user(val, addr); |
10026 | if (ret) | |
10027 | return ret; | |
10028 | if (val) | |
10029 | goto err_size; | |
10030 | } | |
b3e62e35 | 10031 | size = sizeof(*attr); |
974802ea PZ |
10032 | } |
10033 | ||
10034 | ret = copy_from_user(attr, uattr, size); | |
10035 | if (ret) | |
10036 | return -EFAULT; | |
10037 | ||
f12f42ac MX |
10038 | attr->size = size; |
10039 | ||
cd757645 | 10040 | if (attr->__reserved_1) |
974802ea PZ |
10041 | return -EINVAL; |
10042 | ||
10043 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10044 | return -EINVAL; | |
10045 | ||
10046 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10047 | return -EINVAL; | |
10048 | ||
bce38cd5 SE |
10049 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10050 | u64 mask = attr->branch_sample_type; | |
10051 | ||
10052 | /* only using defined bits */ | |
10053 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10054 | return -EINVAL; | |
10055 | ||
10056 | /* at least one branch bit must be set */ | |
10057 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10058 | return -EINVAL; | |
10059 | ||
bce38cd5 SE |
10060 | /* propagate priv level, when not set for branch */ |
10061 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10062 | ||
10063 | /* exclude_kernel checked on syscall entry */ | |
10064 | if (!attr->exclude_kernel) | |
10065 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10066 | ||
10067 | if (!attr->exclude_user) | |
10068 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10069 | ||
10070 | if (!attr->exclude_hv) | |
10071 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10072 | /* | |
10073 | * adjust user setting (for HW filter setup) | |
10074 | */ | |
10075 | attr->branch_sample_type = mask; | |
10076 | } | |
e712209a SE |
10077 | /* privileged levels capture (kernel, hv): check permissions */ |
10078 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
10079 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
10080 | return -EACCES; | |
bce38cd5 | 10081 | } |
4018994f | 10082 | |
c5ebcedb | 10083 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10084 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10085 | if (ret) |
10086 | return ret; | |
10087 | } | |
10088 | ||
10089 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10090 | if (!arch_perf_have_user_stack_dump()) | |
10091 | return -ENOSYS; | |
10092 | ||
10093 | /* | |
10094 | * We have __u32 type for the size, but so far | |
10095 | * we can only use __u16 as maximum due to the | |
10096 | * __u16 sample size limit. | |
10097 | */ | |
10098 | if (attr->sample_stack_user >= USHRT_MAX) | |
10099 | ret = -EINVAL; | |
10100 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
10101 | ret = -EINVAL; | |
10102 | } | |
4018994f | 10103 | |
60e2364e SE |
10104 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10105 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10106 | out: |
10107 | return ret; | |
10108 | ||
10109 | err_size: | |
10110 | put_user(sizeof(*attr), &uattr->size); | |
10111 | ret = -E2BIG; | |
10112 | goto out; | |
10113 | } | |
10114 | ||
ac9721f3 PZ |
10115 | static int |
10116 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 10117 | { |
b69cf536 | 10118 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
10119 | int ret = -EINVAL; |
10120 | ||
ac9721f3 | 10121 | if (!output_event) |
a4be7c27 PZ |
10122 | goto set; |
10123 | ||
ac9721f3 PZ |
10124 | /* don't allow circular references */ |
10125 | if (event == output_event) | |
a4be7c27 PZ |
10126 | goto out; |
10127 | ||
0f139300 PZ |
10128 | /* |
10129 | * Don't allow cross-cpu buffers | |
10130 | */ | |
10131 | if (output_event->cpu != event->cpu) | |
10132 | goto out; | |
10133 | ||
10134 | /* | |
76369139 | 10135 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
10136 | */ |
10137 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
10138 | goto out; | |
10139 | ||
34f43927 PZ |
10140 | /* |
10141 | * Mixing clocks in the same buffer is trouble you don't need. | |
10142 | */ | |
10143 | if (output_event->clock != event->clock) | |
10144 | goto out; | |
10145 | ||
9ecda41a WN |
10146 | /* |
10147 | * Either writing ring buffer from beginning or from end. | |
10148 | * Mixing is not allowed. | |
10149 | */ | |
10150 | if (is_write_backward(output_event) != is_write_backward(event)) | |
10151 | goto out; | |
10152 | ||
45bfb2e5 PZ |
10153 | /* |
10154 | * If both events generate aux data, they must be on the same PMU | |
10155 | */ | |
10156 | if (has_aux(event) && has_aux(output_event) && | |
10157 | event->pmu != output_event->pmu) | |
10158 | goto out; | |
10159 | ||
a4be7c27 | 10160 | set: |
cdd6c482 | 10161 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
10162 | /* Can't redirect output if we've got an active mmap() */ |
10163 | if (atomic_read(&event->mmap_count)) | |
10164 | goto unlock; | |
a4be7c27 | 10165 | |
ac9721f3 | 10166 | if (output_event) { |
76369139 FW |
10167 | /* get the rb we want to redirect to */ |
10168 | rb = ring_buffer_get(output_event); | |
10169 | if (!rb) | |
ac9721f3 | 10170 | goto unlock; |
a4be7c27 PZ |
10171 | } |
10172 | ||
b69cf536 | 10173 | ring_buffer_attach(event, rb); |
9bb5d40c | 10174 | |
a4be7c27 | 10175 | ret = 0; |
ac9721f3 PZ |
10176 | unlock: |
10177 | mutex_unlock(&event->mmap_mutex); | |
10178 | ||
a4be7c27 | 10179 | out: |
a4be7c27 PZ |
10180 | return ret; |
10181 | } | |
10182 | ||
f63a8daa PZ |
10183 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
10184 | { | |
10185 | if (b < a) | |
10186 | swap(a, b); | |
10187 | ||
10188 | mutex_lock(a); | |
10189 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
10190 | } | |
10191 | ||
34f43927 PZ |
10192 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
10193 | { | |
10194 | bool nmi_safe = false; | |
10195 | ||
10196 | switch (clk_id) { | |
10197 | case CLOCK_MONOTONIC: | |
10198 | event->clock = &ktime_get_mono_fast_ns; | |
10199 | nmi_safe = true; | |
10200 | break; | |
10201 | ||
10202 | case CLOCK_MONOTONIC_RAW: | |
10203 | event->clock = &ktime_get_raw_fast_ns; | |
10204 | nmi_safe = true; | |
10205 | break; | |
10206 | ||
10207 | case CLOCK_REALTIME: | |
10208 | event->clock = &ktime_get_real_ns; | |
10209 | break; | |
10210 | ||
10211 | case CLOCK_BOOTTIME: | |
10212 | event->clock = &ktime_get_boot_ns; | |
10213 | break; | |
10214 | ||
10215 | case CLOCK_TAI: | |
10216 | event->clock = &ktime_get_tai_ns; | |
10217 | break; | |
10218 | ||
10219 | default: | |
10220 | return -EINVAL; | |
10221 | } | |
10222 | ||
10223 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
10224 | return -EINVAL; | |
10225 | ||
10226 | return 0; | |
10227 | } | |
10228 | ||
321027c1 PZ |
10229 | /* |
10230 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
10231 | * mutexes. | |
10232 | */ | |
10233 | static struct perf_event_context * | |
10234 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
10235 | struct perf_event_context *ctx) | |
10236 | { | |
10237 | struct perf_event_context *gctx; | |
10238 | ||
10239 | again: | |
10240 | rcu_read_lock(); | |
10241 | gctx = READ_ONCE(group_leader->ctx); | |
10242 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
10243 | rcu_read_unlock(); | |
10244 | goto again; | |
10245 | } | |
10246 | rcu_read_unlock(); | |
10247 | ||
10248 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
10249 | ||
10250 | if (group_leader->ctx != gctx) { | |
10251 | mutex_unlock(&ctx->mutex); | |
10252 | mutex_unlock(&gctx->mutex); | |
10253 | put_ctx(gctx); | |
10254 | goto again; | |
10255 | } | |
10256 | ||
10257 | return gctx; | |
10258 | } | |
10259 | ||
0793a61d | 10260 | /** |
cdd6c482 | 10261 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 10262 | * |
cdd6c482 | 10263 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 10264 | * @pid: target pid |
9f66a381 | 10265 | * @cpu: target cpu |
cdd6c482 | 10266 | * @group_fd: group leader event fd |
0793a61d | 10267 | */ |
cdd6c482 IM |
10268 | SYSCALL_DEFINE5(perf_event_open, |
10269 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 10270 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 10271 | { |
b04243ef PZ |
10272 | struct perf_event *group_leader = NULL, *output_event = NULL; |
10273 | struct perf_event *event, *sibling; | |
cdd6c482 | 10274 | struct perf_event_attr attr; |
f63a8daa | 10275 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 10276 | struct file *event_file = NULL; |
2903ff01 | 10277 | struct fd group = {NULL, 0}; |
38a81da2 | 10278 | struct task_struct *task = NULL; |
89a1e187 | 10279 | struct pmu *pmu; |
ea635c64 | 10280 | int event_fd; |
b04243ef | 10281 | int move_group = 0; |
dc86cabe | 10282 | int err; |
a21b0b35 | 10283 | int f_flags = O_RDWR; |
79dff51e | 10284 | int cgroup_fd = -1; |
0793a61d | 10285 | |
2743a5b0 | 10286 | /* for future expandability... */ |
e5d1367f | 10287 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10288 | return -EINVAL; |
10289 | ||
dc86cabe IM |
10290 | err = perf_copy_attr(attr_uptr, &attr); |
10291 | if (err) | |
10292 | return err; | |
eab656ae | 10293 | |
0764771d PZ |
10294 | if (!attr.exclude_kernel) { |
10295 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10296 | return -EACCES; | |
10297 | } | |
10298 | ||
e4222673 HB |
10299 | if (attr.namespaces) { |
10300 | if (!capable(CAP_SYS_ADMIN)) | |
10301 | return -EACCES; | |
10302 | } | |
10303 | ||
df58ab24 | 10304 | if (attr.freq) { |
cdd6c482 | 10305 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 10306 | return -EINVAL; |
0819b2e3 PZ |
10307 | } else { |
10308 | if (attr.sample_period & (1ULL << 63)) | |
10309 | return -EINVAL; | |
df58ab24 PZ |
10310 | } |
10311 | ||
fc7ce9c7 KL |
10312 | /* Only privileged users can get physical addresses */ |
10313 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && | |
10314 | perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10315 | return -EACCES; | |
10316 | ||
97c79a38 ACM |
10317 | if (!attr.sample_max_stack) |
10318 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
10319 | ||
e5d1367f SE |
10320 | /* |
10321 | * In cgroup mode, the pid argument is used to pass the fd | |
10322 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
10323 | * designates the cpu on which to monitor threads from that | |
10324 | * cgroup. | |
10325 | */ | |
10326 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
10327 | return -EINVAL; | |
10328 | ||
a21b0b35 YD |
10329 | if (flags & PERF_FLAG_FD_CLOEXEC) |
10330 | f_flags |= O_CLOEXEC; | |
10331 | ||
10332 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
10333 | if (event_fd < 0) |
10334 | return event_fd; | |
10335 | ||
ac9721f3 | 10336 | if (group_fd != -1) { |
2903ff01 AV |
10337 | err = perf_fget_light(group_fd, &group); |
10338 | if (err) | |
d14b12d7 | 10339 | goto err_fd; |
2903ff01 | 10340 | group_leader = group.file->private_data; |
ac9721f3 PZ |
10341 | if (flags & PERF_FLAG_FD_OUTPUT) |
10342 | output_event = group_leader; | |
10343 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
10344 | group_leader = NULL; | |
10345 | } | |
10346 | ||
e5d1367f | 10347 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
10348 | task = find_lively_task_by_vpid(pid); |
10349 | if (IS_ERR(task)) { | |
10350 | err = PTR_ERR(task); | |
10351 | goto err_group_fd; | |
10352 | } | |
10353 | } | |
10354 | ||
1f4ee503 PZ |
10355 | if (task && group_leader && |
10356 | group_leader->attr.inherit != attr.inherit) { | |
10357 | err = -EINVAL; | |
10358 | goto err_task; | |
10359 | } | |
10360 | ||
79c9ce57 PZ |
10361 | if (task) { |
10362 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
10363 | if (err) | |
e5aeee51 | 10364 | goto err_task; |
79c9ce57 PZ |
10365 | |
10366 | /* | |
10367 | * Reuse ptrace permission checks for now. | |
10368 | * | |
10369 | * We must hold cred_guard_mutex across this and any potential | |
10370 | * perf_install_in_context() call for this new event to | |
10371 | * serialize against exec() altering our credentials (and the | |
10372 | * perf_event_exit_task() that could imply). | |
10373 | */ | |
10374 | err = -EACCES; | |
10375 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
10376 | goto err_cred; | |
10377 | } | |
10378 | ||
79dff51e MF |
10379 | if (flags & PERF_FLAG_PID_CGROUP) |
10380 | cgroup_fd = pid; | |
10381 | ||
4dc0da86 | 10382 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 10383 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
10384 | if (IS_ERR(event)) { |
10385 | err = PTR_ERR(event); | |
79c9ce57 | 10386 | goto err_cred; |
d14b12d7 SE |
10387 | } |
10388 | ||
53b25335 VW |
10389 | if (is_sampling_event(event)) { |
10390 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 10391 | err = -EOPNOTSUPP; |
53b25335 VW |
10392 | goto err_alloc; |
10393 | } | |
10394 | } | |
10395 | ||
89a1e187 PZ |
10396 | /* |
10397 | * Special case software events and allow them to be part of | |
10398 | * any hardware group. | |
10399 | */ | |
10400 | pmu = event->pmu; | |
b04243ef | 10401 | |
34f43927 PZ |
10402 | if (attr.use_clockid) { |
10403 | err = perf_event_set_clock(event, attr.clockid); | |
10404 | if (err) | |
10405 | goto err_alloc; | |
10406 | } | |
10407 | ||
4ff6a8de DCC |
10408 | if (pmu->task_ctx_nr == perf_sw_context) |
10409 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
10410 | ||
b04243ef PZ |
10411 | if (group_leader && |
10412 | (is_software_event(event) != is_software_event(group_leader))) { | |
10413 | if (is_software_event(event)) { | |
10414 | /* | |
10415 | * If event and group_leader are not both a software | |
10416 | * event, and event is, then group leader is not. | |
10417 | * | |
10418 | * Allow the addition of software events to !software | |
10419 | * groups, this is safe because software events never | |
10420 | * fail to schedule. | |
10421 | */ | |
10422 | pmu = group_leader->pmu; | |
10423 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 10424 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
10425 | /* |
10426 | * In case the group is a pure software group, and we | |
10427 | * try to add a hardware event, move the whole group to | |
10428 | * the hardware context. | |
10429 | */ | |
10430 | move_group = 1; | |
10431 | } | |
10432 | } | |
89a1e187 PZ |
10433 | |
10434 | /* | |
10435 | * Get the target context (task or percpu): | |
10436 | */ | |
4af57ef2 | 10437 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
10438 | if (IS_ERR(ctx)) { |
10439 | err = PTR_ERR(ctx); | |
c6be5a5c | 10440 | goto err_alloc; |
89a1e187 PZ |
10441 | } |
10442 | ||
bed5b25a AS |
10443 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
10444 | err = -EBUSY; | |
10445 | goto err_context; | |
10446 | } | |
10447 | ||
ccff286d | 10448 | /* |
cdd6c482 | 10449 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 10450 | */ |
ac9721f3 | 10451 | if (group_leader) { |
dc86cabe | 10452 | err = -EINVAL; |
04289bb9 | 10453 | |
04289bb9 | 10454 | /* |
ccff286d IM |
10455 | * Do not allow a recursive hierarchy (this new sibling |
10456 | * becoming part of another group-sibling): | |
10457 | */ | |
10458 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 10459 | goto err_context; |
34f43927 PZ |
10460 | |
10461 | /* All events in a group should have the same clock */ | |
10462 | if (group_leader->clock != event->clock) | |
10463 | goto err_context; | |
10464 | ||
ccff286d | 10465 | /* |
64aee2a9 MR |
10466 | * Make sure we're both events for the same CPU; |
10467 | * grouping events for different CPUs is broken; since | |
10468 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 10469 | */ |
64aee2a9 MR |
10470 | if (group_leader->cpu != event->cpu) |
10471 | goto err_context; | |
c3c87e77 | 10472 | |
64aee2a9 MR |
10473 | /* |
10474 | * Make sure we're both on the same task, or both | |
10475 | * per-CPU events. | |
10476 | */ | |
10477 | if (group_leader->ctx->task != ctx->task) | |
10478 | goto err_context; | |
10479 | ||
10480 | /* | |
10481 | * Do not allow to attach to a group in a different task | |
10482 | * or CPU context. If we're moving SW events, we'll fix | |
10483 | * this up later, so allow that. | |
10484 | */ | |
10485 | if (!move_group && group_leader->ctx != ctx) | |
10486 | goto err_context; | |
b04243ef | 10487 | |
3b6f9e5c PM |
10488 | /* |
10489 | * Only a group leader can be exclusive or pinned | |
10490 | */ | |
0d48696f | 10491 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 10492 | goto err_context; |
ac9721f3 PZ |
10493 | } |
10494 | ||
10495 | if (output_event) { | |
10496 | err = perf_event_set_output(event, output_event); | |
10497 | if (err) | |
c3f00c70 | 10498 | goto err_context; |
ac9721f3 | 10499 | } |
0793a61d | 10500 | |
a21b0b35 YD |
10501 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
10502 | f_flags); | |
ea635c64 AV |
10503 | if (IS_ERR(event_file)) { |
10504 | err = PTR_ERR(event_file); | |
201c2f85 | 10505 | event_file = NULL; |
c3f00c70 | 10506 | goto err_context; |
ea635c64 | 10507 | } |
9b51f66d | 10508 | |
b04243ef | 10509 | if (move_group) { |
321027c1 PZ |
10510 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
10511 | ||
84c4e620 PZ |
10512 | if (gctx->task == TASK_TOMBSTONE) { |
10513 | err = -ESRCH; | |
10514 | goto err_locked; | |
10515 | } | |
321027c1 PZ |
10516 | |
10517 | /* | |
10518 | * Check if we raced against another sys_perf_event_open() call | |
10519 | * moving the software group underneath us. | |
10520 | */ | |
10521 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
10522 | /* | |
10523 | * If someone moved the group out from under us, check | |
10524 | * if this new event wound up on the same ctx, if so | |
10525 | * its the regular !move_group case, otherwise fail. | |
10526 | */ | |
10527 | if (gctx != ctx) { | |
10528 | err = -EINVAL; | |
10529 | goto err_locked; | |
10530 | } else { | |
10531 | perf_event_ctx_unlock(group_leader, gctx); | |
10532 | move_group = 0; | |
10533 | } | |
10534 | } | |
f55fc2a5 PZ |
10535 | } else { |
10536 | mutex_lock(&ctx->mutex); | |
10537 | } | |
10538 | ||
84c4e620 PZ |
10539 | if (ctx->task == TASK_TOMBSTONE) { |
10540 | err = -ESRCH; | |
10541 | goto err_locked; | |
10542 | } | |
10543 | ||
a723968c PZ |
10544 | if (!perf_event_validate_size(event)) { |
10545 | err = -E2BIG; | |
10546 | goto err_locked; | |
10547 | } | |
10548 | ||
a63fbed7 TG |
10549 | if (!task) { |
10550 | /* | |
10551 | * Check if the @cpu we're creating an event for is online. | |
10552 | * | |
10553 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
10554 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
10555 | */ | |
10556 | struct perf_cpu_context *cpuctx = | |
10557 | container_of(ctx, struct perf_cpu_context, ctx); | |
10558 | ||
10559 | if (!cpuctx->online) { | |
10560 | err = -ENODEV; | |
10561 | goto err_locked; | |
10562 | } | |
10563 | } | |
10564 | ||
10565 | ||
f55fc2a5 PZ |
10566 | /* |
10567 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
10568 | * because we need to serialize with concurrent event creation. | |
10569 | */ | |
10570 | if (!exclusive_event_installable(event, ctx)) { | |
10571 | /* exclusive and group stuff are assumed mutually exclusive */ | |
10572 | WARN_ON_ONCE(move_group); | |
f63a8daa | 10573 | |
f55fc2a5 PZ |
10574 | err = -EBUSY; |
10575 | goto err_locked; | |
10576 | } | |
f63a8daa | 10577 | |
f55fc2a5 PZ |
10578 | WARN_ON_ONCE(ctx->parent_ctx); |
10579 | ||
79c9ce57 PZ |
10580 | /* |
10581 | * This is the point on no return; we cannot fail hereafter. This is | |
10582 | * where we start modifying current state. | |
10583 | */ | |
10584 | ||
f55fc2a5 | 10585 | if (move_group) { |
f63a8daa PZ |
10586 | /* |
10587 | * See perf_event_ctx_lock() for comments on the details | |
10588 | * of swizzling perf_event::ctx. | |
10589 | */ | |
45a0e07a | 10590 | perf_remove_from_context(group_leader, 0); |
279b5165 | 10591 | put_ctx(gctx); |
0231bb53 | 10592 | |
b04243ef | 10593 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8343aae6 | 10594 | sibling_list) { |
45a0e07a | 10595 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
10596 | put_ctx(gctx); |
10597 | } | |
b04243ef | 10598 | |
f63a8daa PZ |
10599 | /* |
10600 | * Wait for everybody to stop referencing the events through | |
10601 | * the old lists, before installing it on new lists. | |
10602 | */ | |
0cda4c02 | 10603 | synchronize_rcu(); |
f63a8daa | 10604 | |
8f95b435 PZI |
10605 | /* |
10606 | * Install the group siblings before the group leader. | |
10607 | * | |
10608 | * Because a group leader will try and install the entire group | |
10609 | * (through the sibling list, which is still in-tact), we can | |
10610 | * end up with siblings installed in the wrong context. | |
10611 | * | |
10612 | * By installing siblings first we NO-OP because they're not | |
10613 | * reachable through the group lists. | |
10614 | */ | |
b04243ef | 10615 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8343aae6 | 10616 | sibling_list) { |
8f95b435 | 10617 | perf_event__state_init(sibling); |
9fc81d87 | 10618 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
10619 | get_ctx(ctx); |
10620 | } | |
8f95b435 PZI |
10621 | |
10622 | /* | |
10623 | * Removing from the context ends up with disabled | |
10624 | * event. What we want here is event in the initial | |
10625 | * startup state, ready to be add into new context. | |
10626 | */ | |
10627 | perf_event__state_init(group_leader); | |
10628 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
10629 | get_ctx(ctx); | |
bed5b25a AS |
10630 | } |
10631 | ||
f73e22ab PZ |
10632 | /* |
10633 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
10634 | * that we're serialized against further additions and before | |
10635 | * perf_install_in_context() which is the point the event is active and | |
10636 | * can use these values. | |
10637 | */ | |
10638 | perf_event__header_size(event); | |
10639 | perf_event__id_header_size(event); | |
10640 | ||
78cd2c74 PZ |
10641 | event->owner = current; |
10642 | ||
e2d37cd2 | 10643 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 10644 | perf_unpin_context(ctx); |
f63a8daa | 10645 | |
f55fc2a5 | 10646 | if (move_group) |
321027c1 | 10647 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 10648 | mutex_unlock(&ctx->mutex); |
9b51f66d | 10649 | |
79c9ce57 PZ |
10650 | if (task) { |
10651 | mutex_unlock(&task->signal->cred_guard_mutex); | |
10652 | put_task_struct(task); | |
10653 | } | |
10654 | ||
cdd6c482 IM |
10655 | mutex_lock(¤t->perf_event_mutex); |
10656 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
10657 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 10658 | |
8a49542c PZ |
10659 | /* |
10660 | * Drop the reference on the group_event after placing the | |
10661 | * new event on the sibling_list. This ensures destruction | |
10662 | * of the group leader will find the pointer to itself in | |
10663 | * perf_group_detach(). | |
10664 | */ | |
2903ff01 | 10665 | fdput(group); |
ea635c64 AV |
10666 | fd_install(event_fd, event_file); |
10667 | return event_fd; | |
0793a61d | 10668 | |
f55fc2a5 PZ |
10669 | err_locked: |
10670 | if (move_group) | |
321027c1 | 10671 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
10672 | mutex_unlock(&ctx->mutex); |
10673 | /* err_file: */ | |
10674 | fput(event_file); | |
c3f00c70 | 10675 | err_context: |
fe4b04fa | 10676 | perf_unpin_context(ctx); |
ea635c64 | 10677 | put_ctx(ctx); |
c6be5a5c | 10678 | err_alloc: |
13005627 PZ |
10679 | /* |
10680 | * If event_file is set, the fput() above will have called ->release() | |
10681 | * and that will take care of freeing the event. | |
10682 | */ | |
10683 | if (!event_file) | |
10684 | free_event(event); | |
79c9ce57 PZ |
10685 | err_cred: |
10686 | if (task) | |
10687 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 10688 | err_task: |
e7d0bc04 PZ |
10689 | if (task) |
10690 | put_task_struct(task); | |
89a1e187 | 10691 | err_group_fd: |
2903ff01 | 10692 | fdput(group); |
ea635c64 AV |
10693 | err_fd: |
10694 | put_unused_fd(event_fd); | |
dc86cabe | 10695 | return err; |
0793a61d TG |
10696 | } |
10697 | ||
fb0459d7 AV |
10698 | /** |
10699 | * perf_event_create_kernel_counter | |
10700 | * | |
10701 | * @attr: attributes of the counter to create | |
10702 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 10703 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
10704 | */ |
10705 | struct perf_event * | |
10706 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 10707 | struct task_struct *task, |
4dc0da86 AK |
10708 | perf_overflow_handler_t overflow_handler, |
10709 | void *context) | |
fb0459d7 | 10710 | { |
fb0459d7 | 10711 | struct perf_event_context *ctx; |
c3f00c70 | 10712 | struct perf_event *event; |
fb0459d7 | 10713 | int err; |
d859e29f | 10714 | |
fb0459d7 AV |
10715 | /* |
10716 | * Get the target context (task or percpu): | |
10717 | */ | |
d859e29f | 10718 | |
4dc0da86 | 10719 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10720 | overflow_handler, context, -1); |
c3f00c70 PZ |
10721 | if (IS_ERR(event)) { |
10722 | err = PTR_ERR(event); | |
10723 | goto err; | |
10724 | } | |
d859e29f | 10725 | |
f8697762 | 10726 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10727 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10728 | |
4af57ef2 | 10729 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10730 | if (IS_ERR(ctx)) { |
10731 | err = PTR_ERR(ctx); | |
c3f00c70 | 10732 | goto err_free; |
d859e29f | 10733 | } |
fb0459d7 | 10734 | |
fb0459d7 AV |
10735 | WARN_ON_ONCE(ctx->parent_ctx); |
10736 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10737 | if (ctx->task == TASK_TOMBSTONE) { |
10738 | err = -ESRCH; | |
10739 | goto err_unlock; | |
10740 | } | |
10741 | ||
a63fbed7 TG |
10742 | if (!task) { |
10743 | /* | |
10744 | * Check if the @cpu we're creating an event for is online. | |
10745 | * | |
10746 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
10747 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
10748 | */ | |
10749 | struct perf_cpu_context *cpuctx = | |
10750 | container_of(ctx, struct perf_cpu_context, ctx); | |
10751 | if (!cpuctx->online) { | |
10752 | err = -ENODEV; | |
10753 | goto err_unlock; | |
10754 | } | |
10755 | } | |
10756 | ||
bed5b25a | 10757 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10758 | err = -EBUSY; |
84c4e620 | 10759 | goto err_unlock; |
bed5b25a AS |
10760 | } |
10761 | ||
fb0459d7 | 10762 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 10763 | perf_unpin_context(ctx); |
fb0459d7 AV |
10764 | mutex_unlock(&ctx->mutex); |
10765 | ||
fb0459d7 AV |
10766 | return event; |
10767 | ||
84c4e620 PZ |
10768 | err_unlock: |
10769 | mutex_unlock(&ctx->mutex); | |
10770 | perf_unpin_context(ctx); | |
10771 | put_ctx(ctx); | |
c3f00c70 PZ |
10772 | err_free: |
10773 | free_event(event); | |
10774 | err: | |
c6567f64 | 10775 | return ERR_PTR(err); |
9b51f66d | 10776 | } |
fb0459d7 | 10777 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10778 | |
0cda4c02 YZ |
10779 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10780 | { | |
10781 | struct perf_event_context *src_ctx; | |
10782 | struct perf_event_context *dst_ctx; | |
10783 | struct perf_event *event, *tmp; | |
10784 | LIST_HEAD(events); | |
10785 | ||
10786 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10787 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10788 | ||
f63a8daa PZ |
10789 | /* |
10790 | * See perf_event_ctx_lock() for comments on the details | |
10791 | * of swizzling perf_event::ctx. | |
10792 | */ | |
10793 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10794 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10795 | event_entry) { | |
45a0e07a | 10796 | perf_remove_from_context(event, 0); |
9a545de0 | 10797 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10798 | put_ctx(src_ctx); |
9886167d | 10799 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10800 | } |
0cda4c02 | 10801 | |
8f95b435 PZI |
10802 | /* |
10803 | * Wait for the events to quiesce before re-instating them. | |
10804 | */ | |
0cda4c02 YZ |
10805 | synchronize_rcu(); |
10806 | ||
8f95b435 PZI |
10807 | /* |
10808 | * Re-instate events in 2 passes. | |
10809 | * | |
10810 | * Skip over group leaders and only install siblings on this first | |
10811 | * pass, siblings will not get enabled without a leader, however a | |
10812 | * leader will enable its siblings, even if those are still on the old | |
10813 | * context. | |
10814 | */ | |
10815 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10816 | if (event->group_leader == event) | |
10817 | continue; | |
10818 | ||
10819 | list_del(&event->migrate_entry); | |
10820 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10821 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10822 | account_event_cpu(event, dst_cpu); | |
10823 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10824 | get_ctx(dst_ctx); | |
10825 | } | |
10826 | ||
10827 | /* | |
10828 | * Once all the siblings are setup properly, install the group leaders | |
10829 | * to make it go. | |
10830 | */ | |
9886167d PZ |
10831 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10832 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10833 | if (event->state >= PERF_EVENT_STATE_OFF) |
10834 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10835 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10836 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10837 | get_ctx(dst_ctx); | |
10838 | } | |
10839 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10840 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10841 | } |
10842 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10843 | ||
cdd6c482 | 10844 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10845 | struct task_struct *child) |
d859e29f | 10846 | { |
cdd6c482 | 10847 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10848 | u64 child_val; |
d859e29f | 10849 | |
cdd6c482 IM |
10850 | if (child_event->attr.inherit_stat) |
10851 | perf_event_read_event(child_event, child); | |
38b200d6 | 10852 | |
b5e58793 | 10853 | child_val = perf_event_count(child_event); |
d859e29f PM |
10854 | |
10855 | /* | |
10856 | * Add back the child's count to the parent's count: | |
10857 | */ | |
a6e6dea6 | 10858 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10859 | atomic64_add(child_event->total_time_enabled, |
10860 | &parent_event->child_total_time_enabled); | |
10861 | atomic64_add(child_event->total_time_running, | |
10862 | &parent_event->child_total_time_running); | |
d859e29f PM |
10863 | } |
10864 | ||
9b51f66d | 10865 | static void |
8ba289b8 PZ |
10866 | perf_event_exit_event(struct perf_event *child_event, |
10867 | struct perf_event_context *child_ctx, | |
10868 | struct task_struct *child) | |
9b51f66d | 10869 | { |
8ba289b8 PZ |
10870 | struct perf_event *parent_event = child_event->parent; |
10871 | ||
1903d50c PZ |
10872 | /* |
10873 | * Do not destroy the 'original' grouping; because of the context | |
10874 | * switch optimization the original events could've ended up in a | |
10875 | * random child task. | |
10876 | * | |
10877 | * If we were to destroy the original group, all group related | |
10878 | * operations would cease to function properly after this random | |
10879 | * child dies. | |
10880 | * | |
10881 | * Do destroy all inherited groups, we don't care about those | |
10882 | * and being thorough is better. | |
10883 | */ | |
32132a3d PZ |
10884 | raw_spin_lock_irq(&child_ctx->lock); |
10885 | WARN_ON_ONCE(child_ctx->is_active); | |
10886 | ||
8ba289b8 | 10887 | if (parent_event) |
32132a3d PZ |
10888 | perf_group_detach(child_event); |
10889 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 10890 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 10891 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10892 | |
9b51f66d | 10893 | /* |
8ba289b8 | 10894 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10895 | */ |
8ba289b8 | 10896 | if (!parent_event) { |
179033b3 | 10897 | perf_event_wakeup(child_event); |
8ba289b8 | 10898 | return; |
4bcf349a | 10899 | } |
8ba289b8 PZ |
10900 | /* |
10901 | * Child events can be cleaned up. | |
10902 | */ | |
10903 | ||
10904 | sync_child_event(child_event, child); | |
10905 | ||
10906 | /* | |
10907 | * Remove this event from the parent's list | |
10908 | */ | |
10909 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10910 | mutex_lock(&parent_event->child_mutex); | |
10911 | list_del_init(&child_event->child_list); | |
10912 | mutex_unlock(&parent_event->child_mutex); | |
10913 | ||
10914 | /* | |
10915 | * Kick perf_poll() for is_event_hup(). | |
10916 | */ | |
10917 | perf_event_wakeup(parent_event); | |
10918 | free_event(child_event); | |
10919 | put_event(parent_event); | |
9b51f66d IM |
10920 | } |
10921 | ||
8dc85d54 | 10922 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10923 | { |
211de6eb | 10924 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10925 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10926 | |
10927 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10928 | |
6a3351b6 | 10929 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10930 | if (!child_ctx) |
9b51f66d IM |
10931 | return; |
10932 | ||
ad3a37de | 10933 | /* |
6a3351b6 PZ |
10934 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10935 | * ctx::mutex over the entire thing. This serializes against almost | |
10936 | * everything that wants to access the ctx. | |
10937 | * | |
10938 | * The exception is sys_perf_event_open() / | |
10939 | * perf_event_create_kernel_count() which does find_get_context() | |
10940 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10941 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10942 | */ |
6a3351b6 | 10943 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10944 | |
10945 | /* | |
6a3351b6 PZ |
10946 | * In a single ctx::lock section, de-schedule the events and detach the |
10947 | * context from the task such that we cannot ever get it scheduled back | |
10948 | * in. | |
c93f7669 | 10949 | */ |
6a3351b6 | 10950 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 10951 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 10952 | |
71a851b4 | 10953 | /* |
63b6da39 PZ |
10954 | * Now that the context is inactive, destroy the task <-> ctx relation |
10955 | * and mark the context dead. | |
71a851b4 | 10956 | */ |
63b6da39 PZ |
10957 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10958 | put_ctx(child_ctx); /* cannot be last */ | |
10959 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10960 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10961 | |
211de6eb | 10962 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10963 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10964 | |
211de6eb PZ |
10965 | if (clone_ctx) |
10966 | put_ctx(clone_ctx); | |
4a1c0f26 | 10967 | |
9f498cc5 | 10968 | /* |
cdd6c482 IM |
10969 | * Report the task dead after unscheduling the events so that we |
10970 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10971 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10972 | */ |
cdd6c482 | 10973 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10974 | |
ebf905fc | 10975 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10976 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10977 | |
a63eaf34 PM |
10978 | mutex_unlock(&child_ctx->mutex); |
10979 | ||
10980 | put_ctx(child_ctx); | |
9b51f66d IM |
10981 | } |
10982 | ||
8dc85d54 PZ |
10983 | /* |
10984 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10985 | * |
10986 | * Can be called with cred_guard_mutex held when called from | |
10987 | * install_exec_creds(). | |
8dc85d54 PZ |
10988 | */ |
10989 | void perf_event_exit_task(struct task_struct *child) | |
10990 | { | |
8882135b | 10991 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10992 | int ctxn; |
10993 | ||
8882135b PZ |
10994 | mutex_lock(&child->perf_event_mutex); |
10995 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10996 | owner_entry) { | |
10997 | list_del_init(&event->owner_entry); | |
10998 | ||
10999 | /* | |
11000 | * Ensure the list deletion is visible before we clear | |
11001 | * the owner, closes a race against perf_release() where | |
11002 | * we need to serialize on the owner->perf_event_mutex. | |
11003 | */ | |
f47c02c0 | 11004 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11005 | } |
11006 | mutex_unlock(&child->perf_event_mutex); | |
11007 | ||
8dc85d54 PZ |
11008 | for_each_task_context_nr(ctxn) |
11009 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11010 | |
11011 | /* | |
11012 | * The perf_event_exit_task_context calls perf_event_task | |
11013 | * with child's task_ctx, which generates EXIT events for | |
11014 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11015 | * At this point we need to send EXIT events to cpu contexts. | |
11016 | */ | |
11017 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11018 | } |
11019 | ||
889ff015 FW |
11020 | static void perf_free_event(struct perf_event *event, |
11021 | struct perf_event_context *ctx) | |
11022 | { | |
11023 | struct perf_event *parent = event->parent; | |
11024 | ||
11025 | if (WARN_ON_ONCE(!parent)) | |
11026 | return; | |
11027 | ||
11028 | mutex_lock(&parent->child_mutex); | |
11029 | list_del_init(&event->child_list); | |
11030 | mutex_unlock(&parent->child_mutex); | |
11031 | ||
a6fa941d | 11032 | put_event(parent); |
889ff015 | 11033 | |
652884fe | 11034 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11035 | perf_group_detach(event); |
889ff015 | 11036 | list_del_event(event, ctx); |
652884fe | 11037 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11038 | free_event(event); |
11039 | } | |
11040 | ||
bbbee908 | 11041 | /* |
652884fe | 11042 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 11043 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
11044 | * |
11045 | * Not all locks are strictly required, but take them anyway to be nice and | |
11046 | * help out with the lockdep assertions. | |
bbbee908 | 11047 | */ |
cdd6c482 | 11048 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11049 | { |
8dc85d54 | 11050 | struct perf_event_context *ctx; |
cdd6c482 | 11051 | struct perf_event *event, *tmp; |
8dc85d54 | 11052 | int ctxn; |
bbbee908 | 11053 | |
8dc85d54 PZ |
11054 | for_each_task_context_nr(ctxn) { |
11055 | ctx = task->perf_event_ctxp[ctxn]; | |
11056 | if (!ctx) | |
11057 | continue; | |
bbbee908 | 11058 | |
8dc85d54 | 11059 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11060 | raw_spin_lock_irq(&ctx->lock); |
11061 | /* | |
11062 | * Destroy the task <-> ctx relation and mark the context dead. | |
11063 | * | |
11064 | * This is important because even though the task hasn't been | |
11065 | * exposed yet the context has been (through child_list). | |
11066 | */ | |
11067 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11068 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11069 | put_task_struct(task); /* cannot be last */ | |
11070 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11071 | |
15121c78 | 11072 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11073 | perf_free_event(event, ctx); |
bbbee908 | 11074 | |
8dc85d54 | 11075 | mutex_unlock(&ctx->mutex); |
8dc85d54 PZ |
11076 | put_ctx(ctx); |
11077 | } | |
889ff015 FW |
11078 | } |
11079 | ||
4e231c79 PZ |
11080 | void perf_event_delayed_put(struct task_struct *task) |
11081 | { | |
11082 | int ctxn; | |
11083 | ||
11084 | for_each_task_context_nr(ctxn) | |
11085 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
11086 | } | |
11087 | ||
e03e7ee3 | 11088 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 11089 | { |
e03e7ee3 | 11090 | struct file *file; |
ffe8690c | 11091 | |
e03e7ee3 AS |
11092 | file = fget_raw(fd); |
11093 | if (!file) | |
11094 | return ERR_PTR(-EBADF); | |
ffe8690c | 11095 | |
e03e7ee3 AS |
11096 | if (file->f_op != &perf_fops) { |
11097 | fput(file); | |
11098 | return ERR_PTR(-EBADF); | |
11099 | } | |
ffe8690c | 11100 | |
e03e7ee3 | 11101 | return file; |
ffe8690c KX |
11102 | } |
11103 | ||
11104 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
11105 | { | |
11106 | if (!event) | |
11107 | return ERR_PTR(-EINVAL); | |
11108 | ||
11109 | return &event->attr; | |
11110 | } | |
11111 | ||
97dee4f3 | 11112 | /* |
d8a8cfc7 PZ |
11113 | * Inherit a event from parent task to child task. |
11114 | * | |
11115 | * Returns: | |
11116 | * - valid pointer on success | |
11117 | * - NULL for orphaned events | |
11118 | * - IS_ERR() on error | |
97dee4f3 PZ |
11119 | */ |
11120 | static struct perf_event * | |
11121 | inherit_event(struct perf_event *parent_event, | |
11122 | struct task_struct *parent, | |
11123 | struct perf_event_context *parent_ctx, | |
11124 | struct task_struct *child, | |
11125 | struct perf_event *group_leader, | |
11126 | struct perf_event_context *child_ctx) | |
11127 | { | |
8ca2bd41 | 11128 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 11129 | struct perf_event *child_event; |
cee010ec | 11130 | unsigned long flags; |
97dee4f3 PZ |
11131 | |
11132 | /* | |
11133 | * Instead of creating recursive hierarchies of events, | |
11134 | * we link inherited events back to the original parent, | |
11135 | * which has a filp for sure, which we use as the reference | |
11136 | * count: | |
11137 | */ | |
11138 | if (parent_event->parent) | |
11139 | parent_event = parent_event->parent; | |
11140 | ||
11141 | child_event = perf_event_alloc(&parent_event->attr, | |
11142 | parent_event->cpu, | |
d580ff86 | 11143 | child, |
97dee4f3 | 11144 | group_leader, parent_event, |
79dff51e | 11145 | NULL, NULL, -1); |
97dee4f3 PZ |
11146 | if (IS_ERR(child_event)) |
11147 | return child_event; | |
a6fa941d | 11148 | |
313ccb96 JO |
11149 | |
11150 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
11151 | !child_ctx->task_ctx_data) { | |
11152 | struct pmu *pmu = child_event->pmu; | |
11153 | ||
11154 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
11155 | GFP_KERNEL); | |
11156 | if (!child_ctx->task_ctx_data) { | |
11157 | free_event(child_event); | |
11158 | return NULL; | |
11159 | } | |
11160 | } | |
11161 | ||
c6e5b732 PZ |
11162 | /* |
11163 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
11164 | * must be under the same lock in order to serialize against | |
11165 | * perf_event_release_kernel(), such that either we must observe | |
11166 | * is_orphaned_event() or they will observe us on the child_list. | |
11167 | */ | |
11168 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
11169 | if (is_orphaned_event(parent_event) || |
11170 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 11171 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 11172 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
11173 | free_event(child_event); |
11174 | return NULL; | |
11175 | } | |
11176 | ||
97dee4f3 PZ |
11177 | get_ctx(child_ctx); |
11178 | ||
11179 | /* | |
11180 | * Make the child state follow the state of the parent event, | |
11181 | * not its attr.disabled bit. We hold the parent's mutex, | |
11182 | * so we won't race with perf_event_{en, dis}able_family. | |
11183 | */ | |
1929def9 | 11184 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
11185 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
11186 | else | |
11187 | child_event->state = PERF_EVENT_STATE_OFF; | |
11188 | ||
11189 | if (parent_event->attr.freq) { | |
11190 | u64 sample_period = parent_event->hw.sample_period; | |
11191 | struct hw_perf_event *hwc = &child_event->hw; | |
11192 | ||
11193 | hwc->sample_period = sample_period; | |
11194 | hwc->last_period = sample_period; | |
11195 | ||
11196 | local64_set(&hwc->period_left, sample_period); | |
11197 | } | |
11198 | ||
11199 | child_event->ctx = child_ctx; | |
11200 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
11201 | child_event->overflow_handler_context |
11202 | = parent_event->overflow_handler_context; | |
97dee4f3 | 11203 | |
614b6780 TG |
11204 | /* |
11205 | * Precalculate sample_data sizes | |
11206 | */ | |
11207 | perf_event__header_size(child_event); | |
6844c09d | 11208 | perf_event__id_header_size(child_event); |
614b6780 | 11209 | |
97dee4f3 PZ |
11210 | /* |
11211 | * Link it up in the child's context: | |
11212 | */ | |
cee010ec | 11213 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 11214 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 11215 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 11216 | |
97dee4f3 PZ |
11217 | /* |
11218 | * Link this into the parent event's child list | |
11219 | */ | |
97dee4f3 PZ |
11220 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
11221 | mutex_unlock(&parent_event->child_mutex); | |
11222 | ||
11223 | return child_event; | |
11224 | } | |
11225 | ||
d8a8cfc7 PZ |
11226 | /* |
11227 | * Inherits an event group. | |
11228 | * | |
11229 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
11230 | * This matches with perf_event_release_kernel() removing all child events. | |
11231 | * | |
11232 | * Returns: | |
11233 | * - 0 on success | |
11234 | * - <0 on error | |
11235 | */ | |
97dee4f3 PZ |
11236 | static int inherit_group(struct perf_event *parent_event, |
11237 | struct task_struct *parent, | |
11238 | struct perf_event_context *parent_ctx, | |
11239 | struct task_struct *child, | |
11240 | struct perf_event_context *child_ctx) | |
11241 | { | |
11242 | struct perf_event *leader; | |
11243 | struct perf_event *sub; | |
11244 | struct perf_event *child_ctr; | |
11245 | ||
11246 | leader = inherit_event(parent_event, parent, parent_ctx, | |
11247 | child, NULL, child_ctx); | |
11248 | if (IS_ERR(leader)) | |
11249 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
11250 | /* |
11251 | * @leader can be NULL here because of is_orphaned_event(). In this | |
11252 | * case inherit_event() will create individual events, similar to what | |
11253 | * perf_group_detach() would do anyway. | |
11254 | */ | |
8343aae6 | 11255 | list_for_each_entry(sub, &parent_event->sibling_list, sibling_list) { |
97dee4f3 PZ |
11256 | child_ctr = inherit_event(sub, parent, parent_ctx, |
11257 | child, leader, child_ctx); | |
11258 | if (IS_ERR(child_ctr)) | |
11259 | return PTR_ERR(child_ctr); | |
11260 | } | |
11261 | return 0; | |
889ff015 FW |
11262 | } |
11263 | ||
d8a8cfc7 PZ |
11264 | /* |
11265 | * Creates the child task context and tries to inherit the event-group. | |
11266 | * | |
11267 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
11268 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
11269 | * consistent with perf_event_release_kernel() removing all child events. | |
11270 | * | |
11271 | * Returns: | |
11272 | * - 0 on success | |
11273 | * - <0 on error | |
11274 | */ | |
889ff015 FW |
11275 | static int |
11276 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
11277 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 11278 | struct task_struct *child, int ctxn, |
889ff015 FW |
11279 | int *inherited_all) |
11280 | { | |
11281 | int ret; | |
8dc85d54 | 11282 | struct perf_event_context *child_ctx; |
889ff015 FW |
11283 | |
11284 | if (!event->attr.inherit) { | |
11285 | *inherited_all = 0; | |
11286 | return 0; | |
bbbee908 PZ |
11287 | } |
11288 | ||
fe4b04fa | 11289 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
11290 | if (!child_ctx) { |
11291 | /* | |
11292 | * This is executed from the parent task context, so | |
11293 | * inherit events that have been marked for cloning. | |
11294 | * First allocate and initialize a context for the | |
11295 | * child. | |
11296 | */ | |
734df5ab | 11297 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
11298 | if (!child_ctx) |
11299 | return -ENOMEM; | |
bbbee908 | 11300 | |
8dc85d54 | 11301 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
11302 | } |
11303 | ||
11304 | ret = inherit_group(event, parent, parent_ctx, | |
11305 | child, child_ctx); | |
11306 | ||
11307 | if (ret) | |
11308 | *inherited_all = 0; | |
11309 | ||
11310 | return ret; | |
bbbee908 PZ |
11311 | } |
11312 | ||
9b51f66d | 11313 | /* |
cdd6c482 | 11314 | * Initialize the perf_event context in task_struct |
9b51f66d | 11315 | */ |
985c8dcb | 11316 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 11317 | { |
889ff015 | 11318 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
11319 | struct perf_event_context *cloned_ctx; |
11320 | struct perf_event *event; | |
9b51f66d | 11321 | struct task_struct *parent = current; |
564c2b21 | 11322 | int inherited_all = 1; |
dddd3379 | 11323 | unsigned long flags; |
6ab423e0 | 11324 | int ret = 0; |
9b51f66d | 11325 | |
8dc85d54 | 11326 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
11327 | return 0; |
11328 | ||
ad3a37de | 11329 | /* |
25346b93 PM |
11330 | * If the parent's context is a clone, pin it so it won't get |
11331 | * swapped under us. | |
ad3a37de | 11332 | */ |
8dc85d54 | 11333 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
11334 | if (!parent_ctx) |
11335 | return 0; | |
25346b93 | 11336 | |
ad3a37de PM |
11337 | /* |
11338 | * No need to check if parent_ctx != NULL here; since we saw | |
11339 | * it non-NULL earlier, the only reason for it to become NULL | |
11340 | * is if we exit, and since we're currently in the middle of | |
11341 | * a fork we can't be exiting at the same time. | |
11342 | */ | |
ad3a37de | 11343 | |
9b51f66d IM |
11344 | /* |
11345 | * Lock the parent list. No need to lock the child - not PID | |
11346 | * hashed yet and not running, so nobody can access it. | |
11347 | */ | |
d859e29f | 11348 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
11349 | |
11350 | /* | |
11351 | * We dont have to disable NMIs - we are only looking at | |
11352 | * the list, not manipulating it: | |
11353 | */ | |
6e6804d2 | 11354 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
11355 | ret = inherit_task_group(event, parent, parent_ctx, |
11356 | child, ctxn, &inherited_all); | |
889ff015 | 11357 | if (ret) |
e7cc4865 | 11358 | goto out_unlock; |
889ff015 | 11359 | } |
b93f7978 | 11360 | |
dddd3379 TG |
11361 | /* |
11362 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
11363 | * to allocations, but we need to prevent rotation because | |
11364 | * rotate_ctx() will change the list from interrupt context. | |
11365 | */ | |
11366 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
11367 | parent_ctx->rotate_disable = 1; | |
11368 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
11369 | ||
6e6804d2 | 11370 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
11371 | ret = inherit_task_group(event, parent, parent_ctx, |
11372 | child, ctxn, &inherited_all); | |
889ff015 | 11373 | if (ret) |
e7cc4865 | 11374 | goto out_unlock; |
564c2b21 PM |
11375 | } |
11376 | ||
dddd3379 TG |
11377 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
11378 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 11379 | |
8dc85d54 | 11380 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 11381 | |
05cbaa28 | 11382 | if (child_ctx && inherited_all) { |
564c2b21 PM |
11383 | /* |
11384 | * Mark the child context as a clone of the parent | |
11385 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
11386 | * |
11387 | * Note that if the parent is a clone, the holding of | |
11388 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 11389 | */ |
c5ed5145 | 11390 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
11391 | if (cloned_ctx) { |
11392 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 11393 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
11394 | } else { |
11395 | child_ctx->parent_ctx = parent_ctx; | |
11396 | child_ctx->parent_gen = parent_ctx->generation; | |
11397 | } | |
11398 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
11399 | } |
11400 | ||
c5ed5145 | 11401 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 11402 | out_unlock: |
d859e29f | 11403 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 11404 | |
25346b93 | 11405 | perf_unpin_context(parent_ctx); |
fe4b04fa | 11406 | put_ctx(parent_ctx); |
ad3a37de | 11407 | |
6ab423e0 | 11408 | return ret; |
9b51f66d IM |
11409 | } |
11410 | ||
8dc85d54 PZ |
11411 | /* |
11412 | * Initialize the perf_event context in task_struct | |
11413 | */ | |
11414 | int perf_event_init_task(struct task_struct *child) | |
11415 | { | |
11416 | int ctxn, ret; | |
11417 | ||
8550d7cb ON |
11418 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
11419 | mutex_init(&child->perf_event_mutex); | |
11420 | INIT_LIST_HEAD(&child->perf_event_list); | |
11421 | ||
8dc85d54 PZ |
11422 | for_each_task_context_nr(ctxn) { |
11423 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
11424 | if (ret) { |
11425 | perf_event_free_task(child); | |
8dc85d54 | 11426 | return ret; |
6c72e350 | 11427 | } |
8dc85d54 PZ |
11428 | } |
11429 | ||
11430 | return 0; | |
11431 | } | |
11432 | ||
220b140b PM |
11433 | static void __init perf_event_init_all_cpus(void) |
11434 | { | |
b28ab83c | 11435 | struct swevent_htable *swhash; |
220b140b | 11436 | int cpu; |
220b140b | 11437 | |
a63fbed7 TG |
11438 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
11439 | ||
220b140b | 11440 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
11441 | swhash = &per_cpu(swevent_htable, cpu); |
11442 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 11443 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
11444 | |
11445 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
11446 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 11447 | |
058fe1c0 DCC |
11448 | #ifdef CONFIG_CGROUP_PERF |
11449 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
11450 | #endif | |
e48c1788 | 11451 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
11452 | } |
11453 | } | |
11454 | ||
a63fbed7 | 11455 | void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 11456 | { |
108b02cf | 11457 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 11458 | |
b28ab83c | 11459 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 11460 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
11461 | struct swevent_hlist *hlist; |
11462 | ||
b28ab83c PZ |
11463 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
11464 | WARN_ON(!hlist); | |
11465 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 11466 | } |
b28ab83c | 11467 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
11468 | } |
11469 | ||
2965faa5 | 11470 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 11471 | static void __perf_event_exit_context(void *__info) |
0793a61d | 11472 | { |
108b02cf | 11473 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
11474 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
11475 | struct perf_event *event; | |
0793a61d | 11476 | |
fae3fde6 | 11477 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 11478 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 11479 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 11480 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 11481 | raw_spin_unlock(&ctx->lock); |
0793a61d | 11482 | } |
108b02cf PZ |
11483 | |
11484 | static void perf_event_exit_cpu_context(int cpu) | |
11485 | { | |
a63fbed7 | 11486 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
11487 | struct perf_event_context *ctx; |
11488 | struct pmu *pmu; | |
108b02cf | 11489 | |
a63fbed7 TG |
11490 | mutex_lock(&pmus_lock); |
11491 | list_for_each_entry(pmu, &pmus, entry) { | |
11492 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11493 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
11494 | |
11495 | mutex_lock(&ctx->mutex); | |
11496 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 11497 | cpuctx->online = 0; |
108b02cf PZ |
11498 | mutex_unlock(&ctx->mutex); |
11499 | } | |
a63fbed7 TG |
11500 | cpumask_clear_cpu(cpu, perf_online_mask); |
11501 | mutex_unlock(&pmus_lock); | |
108b02cf | 11502 | } |
00e16c3d TG |
11503 | #else |
11504 | ||
11505 | static void perf_event_exit_cpu_context(int cpu) { } | |
11506 | ||
11507 | #endif | |
108b02cf | 11508 | |
a63fbed7 TG |
11509 | int perf_event_init_cpu(unsigned int cpu) |
11510 | { | |
11511 | struct perf_cpu_context *cpuctx; | |
11512 | struct perf_event_context *ctx; | |
11513 | struct pmu *pmu; | |
11514 | ||
11515 | perf_swevent_init_cpu(cpu); | |
11516 | ||
11517 | mutex_lock(&pmus_lock); | |
11518 | cpumask_set_cpu(cpu, perf_online_mask); | |
11519 | list_for_each_entry(pmu, &pmus, entry) { | |
11520 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11521 | ctx = &cpuctx->ctx; | |
11522 | ||
11523 | mutex_lock(&ctx->mutex); | |
11524 | cpuctx->online = 1; | |
11525 | mutex_unlock(&ctx->mutex); | |
11526 | } | |
11527 | mutex_unlock(&pmus_lock); | |
11528 | ||
11529 | return 0; | |
11530 | } | |
11531 | ||
00e16c3d | 11532 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 11533 | { |
e3703f8c | 11534 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 11535 | return 0; |
0793a61d | 11536 | } |
0793a61d | 11537 | |
c277443c PZ |
11538 | static int |
11539 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
11540 | { | |
11541 | int cpu; | |
11542 | ||
11543 | for_each_online_cpu(cpu) | |
11544 | perf_event_exit_cpu(cpu); | |
11545 | ||
11546 | return NOTIFY_OK; | |
11547 | } | |
11548 | ||
11549 | /* | |
11550 | * Run the perf reboot notifier at the very last possible moment so that | |
11551 | * the generic watchdog code runs as long as possible. | |
11552 | */ | |
11553 | static struct notifier_block perf_reboot_notifier = { | |
11554 | .notifier_call = perf_reboot, | |
11555 | .priority = INT_MIN, | |
11556 | }; | |
11557 | ||
cdd6c482 | 11558 | void __init perf_event_init(void) |
0793a61d | 11559 | { |
3c502e7a JW |
11560 | int ret; |
11561 | ||
2e80a82a PZ |
11562 | idr_init(&pmu_idr); |
11563 | ||
220b140b | 11564 | perf_event_init_all_cpus(); |
b0a873eb | 11565 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
11566 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
11567 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
11568 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 11569 | perf_tp_register(); |
00e16c3d | 11570 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 11571 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
11572 | |
11573 | ret = init_hw_breakpoint(); | |
11574 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 11575 | |
b01c3a00 JO |
11576 | /* |
11577 | * Build time assertion that we keep the data_head at the intended | |
11578 | * location. IOW, validation we got the __reserved[] size right. | |
11579 | */ | |
11580 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
11581 | != 1024); | |
0793a61d | 11582 | } |
abe43400 | 11583 | |
fd979c01 CS |
11584 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
11585 | char *page) | |
11586 | { | |
11587 | struct perf_pmu_events_attr *pmu_attr = | |
11588 | container_of(attr, struct perf_pmu_events_attr, attr); | |
11589 | ||
11590 | if (pmu_attr->event_str) | |
11591 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
11592 | ||
11593 | return 0; | |
11594 | } | |
675965b0 | 11595 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 11596 | |
abe43400 PZ |
11597 | static int __init perf_event_sysfs_init(void) |
11598 | { | |
11599 | struct pmu *pmu; | |
11600 | int ret; | |
11601 | ||
11602 | mutex_lock(&pmus_lock); | |
11603 | ||
11604 | ret = bus_register(&pmu_bus); | |
11605 | if (ret) | |
11606 | goto unlock; | |
11607 | ||
11608 | list_for_each_entry(pmu, &pmus, entry) { | |
11609 | if (!pmu->name || pmu->type < 0) | |
11610 | continue; | |
11611 | ||
11612 | ret = pmu_dev_alloc(pmu); | |
11613 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
11614 | } | |
11615 | pmu_bus_running = 1; | |
11616 | ret = 0; | |
11617 | ||
11618 | unlock: | |
11619 | mutex_unlock(&pmus_lock); | |
11620 | ||
11621 | return ret; | |
11622 | } | |
11623 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
11624 | |
11625 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
11626 | static struct cgroup_subsys_state * |
11627 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
11628 | { |
11629 | struct perf_cgroup *jc; | |
e5d1367f | 11630 | |
1b15d055 | 11631 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
11632 | if (!jc) |
11633 | return ERR_PTR(-ENOMEM); | |
11634 | ||
e5d1367f SE |
11635 | jc->info = alloc_percpu(struct perf_cgroup_info); |
11636 | if (!jc->info) { | |
11637 | kfree(jc); | |
11638 | return ERR_PTR(-ENOMEM); | |
11639 | } | |
11640 | ||
e5d1367f SE |
11641 | return &jc->css; |
11642 | } | |
11643 | ||
eb95419b | 11644 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 11645 | { |
eb95419b TH |
11646 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
11647 | ||
e5d1367f SE |
11648 | free_percpu(jc->info); |
11649 | kfree(jc); | |
11650 | } | |
11651 | ||
11652 | static int __perf_cgroup_move(void *info) | |
11653 | { | |
11654 | struct task_struct *task = info; | |
ddaaf4e2 | 11655 | rcu_read_lock(); |
e5d1367f | 11656 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 11657 | rcu_read_unlock(); |
e5d1367f SE |
11658 | return 0; |
11659 | } | |
11660 | ||
1f7dd3e5 | 11661 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 11662 | { |
bb9d97b6 | 11663 | struct task_struct *task; |
1f7dd3e5 | 11664 | struct cgroup_subsys_state *css; |
bb9d97b6 | 11665 | |
1f7dd3e5 | 11666 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 11667 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
11668 | } |
11669 | ||
073219e9 | 11670 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
11671 | .css_alloc = perf_cgroup_css_alloc, |
11672 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 11673 | .attach = perf_cgroup_attach, |
968ebff1 TH |
11674 | /* |
11675 | * Implicitly enable on dfl hierarchy so that perf events can | |
11676 | * always be filtered by cgroup2 path as long as perf_event | |
11677 | * controller is not mounted on a legacy hierarchy. | |
11678 | */ | |
11679 | .implicit_on_dfl = true, | |
8cfd8147 | 11680 | .threaded = true, |
e5d1367f SE |
11681 | }; |
11682 | #endif /* CONFIG_CGROUP_PERF */ |