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Commit | Line | Data |
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0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
7b732a75 | 8 | * |
57c0c15b | 9 | * For licensing details see kernel-base/COPYING |
0793a61d TG |
10 | */ |
11 | ||
12 | #include <linux/fs.h> | |
b9cacc7b | 13 | #include <linux/mm.h> |
0793a61d TG |
14 | #include <linux/cpu.h> |
15 | #include <linux/smp.h> | |
2e80a82a | 16 | #include <linux/idr.h> |
04289bb9 | 17 | #include <linux/file.h> |
0793a61d | 18 | #include <linux/poll.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
76e1d904 | 20 | #include <linux/hash.h> |
12351ef8 | 21 | #include <linux/tick.h> |
0793a61d | 22 | #include <linux/sysfs.h> |
22a4f650 | 23 | #include <linux/dcache.h> |
0793a61d | 24 | #include <linux/percpu.h> |
22a4f650 | 25 | #include <linux/ptrace.h> |
c277443c | 26 | #include <linux/reboot.h> |
b9cacc7b | 27 | #include <linux/vmstat.h> |
abe43400 | 28 | #include <linux/device.h> |
6e5fdeed | 29 | #include <linux/export.h> |
906010b2 | 30 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
31 | #include <linux/hardirq.h> |
32 | #include <linux/rculist.h> | |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
375637bc AS |
47 | #include <linux/namei.h> |
48 | #include <linux/parser.h> | |
0793a61d | 49 | |
76369139 FW |
50 | #include "internal.h" |
51 | ||
4e193bd4 TB |
52 | #include <asm/irq_regs.h> |
53 | ||
272325c4 PZ |
54 | typedef int (*remote_function_f)(void *); |
55 | ||
fe4b04fa | 56 | struct remote_function_call { |
e7e7ee2e | 57 | struct task_struct *p; |
272325c4 | 58 | remote_function_f func; |
e7e7ee2e IM |
59 | void *info; |
60 | int ret; | |
fe4b04fa PZ |
61 | }; |
62 | ||
63 | static void remote_function(void *data) | |
64 | { | |
65 | struct remote_function_call *tfc = data; | |
66 | struct task_struct *p = tfc->p; | |
67 | ||
68 | if (p) { | |
0da4cf3e PZ |
69 | /* -EAGAIN */ |
70 | if (task_cpu(p) != smp_processor_id()) | |
71 | return; | |
72 | ||
73 | /* | |
74 | * Now that we're on right CPU with IRQs disabled, we can test | |
75 | * if we hit the right task without races. | |
76 | */ | |
77 | ||
78 | tfc->ret = -ESRCH; /* No such (running) process */ | |
79 | if (p != current) | |
fe4b04fa PZ |
80 | return; |
81 | } | |
82 | ||
83 | tfc->ret = tfc->func(tfc->info); | |
84 | } | |
85 | ||
86 | /** | |
87 | * task_function_call - call a function on the cpu on which a task runs | |
88 | * @p: the task to evaluate | |
89 | * @func: the function to be called | |
90 | * @info: the function call argument | |
91 | * | |
92 | * Calls the function @func when the task is currently running. This might | |
93 | * be on the current CPU, which just calls the function directly | |
94 | * | |
95 | * returns: @func return value, or | |
96 | * -ESRCH - when the process isn't running | |
97 | * -EAGAIN - when the process moved away | |
98 | */ | |
99 | static int | |
272325c4 | 100 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
101 | { |
102 | struct remote_function_call data = { | |
e7e7ee2e IM |
103 | .p = p, |
104 | .func = func, | |
105 | .info = info, | |
0da4cf3e | 106 | .ret = -EAGAIN, |
fe4b04fa | 107 | }; |
0da4cf3e | 108 | int ret; |
fe4b04fa | 109 | |
0da4cf3e PZ |
110 | do { |
111 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
112 | if (!ret) | |
113 | ret = data.ret; | |
114 | } while (ret == -EAGAIN); | |
fe4b04fa | 115 | |
0da4cf3e | 116 | return ret; |
fe4b04fa PZ |
117 | } |
118 | ||
119 | /** | |
120 | * cpu_function_call - call a function on the cpu | |
121 | * @func: the function to be called | |
122 | * @info: the function call argument | |
123 | * | |
124 | * Calls the function @func on the remote cpu. | |
125 | * | |
126 | * returns: @func return value or -ENXIO when the cpu is offline | |
127 | */ | |
272325c4 | 128 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
129 | { |
130 | struct remote_function_call data = { | |
e7e7ee2e IM |
131 | .p = NULL, |
132 | .func = func, | |
133 | .info = info, | |
134 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
135 | }; |
136 | ||
137 | smp_call_function_single(cpu, remote_function, &data, 1); | |
138 | ||
139 | return data.ret; | |
140 | } | |
141 | ||
fae3fde6 PZ |
142 | static inline struct perf_cpu_context * |
143 | __get_cpu_context(struct perf_event_context *ctx) | |
144 | { | |
145 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
146 | } | |
147 | ||
148 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
149 | struct perf_event_context *ctx) | |
0017960f | 150 | { |
fae3fde6 PZ |
151 | raw_spin_lock(&cpuctx->ctx.lock); |
152 | if (ctx) | |
153 | raw_spin_lock(&ctx->lock); | |
154 | } | |
155 | ||
156 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
157 | struct perf_event_context *ctx) | |
158 | { | |
159 | if (ctx) | |
160 | raw_spin_unlock(&ctx->lock); | |
161 | raw_spin_unlock(&cpuctx->ctx.lock); | |
162 | } | |
163 | ||
63b6da39 PZ |
164 | #define TASK_TOMBSTONE ((void *)-1L) |
165 | ||
166 | static bool is_kernel_event(struct perf_event *event) | |
167 | { | |
f47c02c0 | 168 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
169 | } |
170 | ||
39a43640 PZ |
171 | /* |
172 | * On task ctx scheduling... | |
173 | * | |
174 | * When !ctx->nr_events a task context will not be scheduled. This means | |
175 | * we can disable the scheduler hooks (for performance) without leaving | |
176 | * pending task ctx state. | |
177 | * | |
178 | * This however results in two special cases: | |
179 | * | |
180 | * - removing the last event from a task ctx; this is relatively straight | |
181 | * forward and is done in __perf_remove_from_context. | |
182 | * | |
183 | * - adding the first event to a task ctx; this is tricky because we cannot | |
184 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
185 | * See perf_install_in_context(). | |
186 | * | |
39a43640 PZ |
187 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
188 | */ | |
189 | ||
fae3fde6 PZ |
190 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
191 | struct perf_event_context *, void *); | |
192 | ||
193 | struct event_function_struct { | |
194 | struct perf_event *event; | |
195 | event_f func; | |
196 | void *data; | |
197 | }; | |
198 | ||
199 | static int event_function(void *info) | |
200 | { | |
201 | struct event_function_struct *efs = info; | |
202 | struct perf_event *event = efs->event; | |
0017960f | 203 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
204 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
205 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 206 | int ret = 0; |
fae3fde6 PZ |
207 | |
208 | WARN_ON_ONCE(!irqs_disabled()); | |
209 | ||
63b6da39 | 210 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
211 | /* |
212 | * Since we do the IPI call without holding ctx->lock things can have | |
213 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
214 | */ |
215 | if (ctx->task) { | |
63b6da39 | 216 | if (ctx->task != current) { |
0da4cf3e | 217 | ret = -ESRCH; |
63b6da39 PZ |
218 | goto unlock; |
219 | } | |
fae3fde6 | 220 | |
fae3fde6 PZ |
221 | /* |
222 | * We only use event_function_call() on established contexts, | |
223 | * and event_function() is only ever called when active (or | |
224 | * rather, we'll have bailed in task_function_call() or the | |
225 | * above ctx->task != current test), therefore we must have | |
226 | * ctx->is_active here. | |
227 | */ | |
228 | WARN_ON_ONCE(!ctx->is_active); | |
229 | /* | |
230 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
231 | * match. | |
232 | */ | |
63b6da39 PZ |
233 | WARN_ON_ONCE(task_ctx != ctx); |
234 | } else { | |
235 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 236 | } |
63b6da39 | 237 | |
fae3fde6 | 238 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 239 | unlock: |
fae3fde6 PZ |
240 | perf_ctx_unlock(cpuctx, task_ctx); |
241 | ||
63b6da39 | 242 | return ret; |
fae3fde6 PZ |
243 | } |
244 | ||
fae3fde6 | 245 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
246 | { |
247 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 248 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
249 | struct event_function_struct efs = { |
250 | .event = event, | |
251 | .func = func, | |
252 | .data = data, | |
253 | }; | |
0017960f | 254 | |
c97f4736 PZ |
255 | if (!event->parent) { |
256 | /* | |
257 | * If this is a !child event, we must hold ctx::mutex to | |
258 | * stabilize the the event->ctx relation. See | |
259 | * perf_event_ctx_lock(). | |
260 | */ | |
261 | lockdep_assert_held(&ctx->mutex); | |
262 | } | |
0017960f PZ |
263 | |
264 | if (!task) { | |
fae3fde6 | 265 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
266 | return; |
267 | } | |
268 | ||
63b6da39 PZ |
269 | if (task == TASK_TOMBSTONE) |
270 | return; | |
271 | ||
a096309b | 272 | again: |
fae3fde6 | 273 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
274 | return; |
275 | ||
276 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
277 | /* |
278 | * Reload the task pointer, it might have been changed by | |
279 | * a concurrent perf_event_context_sched_out(). | |
280 | */ | |
281 | task = ctx->task; | |
a096309b PZ |
282 | if (task == TASK_TOMBSTONE) { |
283 | raw_spin_unlock_irq(&ctx->lock); | |
284 | return; | |
0017960f | 285 | } |
a096309b PZ |
286 | if (ctx->is_active) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | goto again; | |
289 | } | |
290 | func(event, NULL, ctx, data); | |
0017960f PZ |
291 | raw_spin_unlock_irq(&ctx->lock); |
292 | } | |
293 | ||
cca20946 PZ |
294 | /* |
295 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
296 | * are already disabled and we're on the right CPU. | |
297 | */ | |
298 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
299 | { | |
300 | struct perf_event_context *ctx = event->ctx; | |
301 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
302 | struct task_struct *task = READ_ONCE(ctx->task); | |
303 | struct perf_event_context *task_ctx = NULL; | |
304 | ||
305 | WARN_ON_ONCE(!irqs_disabled()); | |
306 | ||
307 | if (task) { | |
308 | if (task == TASK_TOMBSTONE) | |
309 | return; | |
310 | ||
311 | task_ctx = ctx; | |
312 | } | |
313 | ||
314 | perf_ctx_lock(cpuctx, task_ctx); | |
315 | ||
316 | task = ctx->task; | |
317 | if (task == TASK_TOMBSTONE) | |
318 | goto unlock; | |
319 | ||
320 | if (task) { | |
321 | /* | |
322 | * We must be either inactive or active and the right task, | |
323 | * otherwise we're screwed, since we cannot IPI to somewhere | |
324 | * else. | |
325 | */ | |
326 | if (ctx->is_active) { | |
327 | if (WARN_ON_ONCE(task != current)) | |
328 | goto unlock; | |
329 | ||
330 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
331 | goto unlock; | |
332 | } | |
333 | } else { | |
334 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
335 | } | |
336 | ||
337 | func(event, cpuctx, ctx, data); | |
338 | unlock: | |
339 | perf_ctx_unlock(cpuctx, task_ctx); | |
340 | } | |
341 | ||
e5d1367f SE |
342 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
343 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
344 | PERF_FLAG_PID_CGROUP |\ |
345 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 346 | |
bce38cd5 SE |
347 | /* |
348 | * branch priv levels that need permission checks | |
349 | */ | |
350 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
351 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
352 | PERF_SAMPLE_BRANCH_HV) | |
353 | ||
0b3fcf17 SE |
354 | enum event_type_t { |
355 | EVENT_FLEXIBLE = 0x1, | |
356 | EVENT_PINNED = 0x2, | |
3cbaa590 | 357 | EVENT_TIME = 0x4, |
0b3fcf17 SE |
358 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
359 | }; | |
360 | ||
e5d1367f SE |
361 | /* |
362 | * perf_sched_events : >0 events exist | |
363 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
364 | */ | |
9107c89e PZ |
365 | |
366 | static void perf_sched_delayed(struct work_struct *work); | |
367 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
368 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
369 | static DEFINE_MUTEX(perf_sched_mutex); | |
370 | static atomic_t perf_sched_count; | |
371 | ||
e5d1367f | 372 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 373 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 374 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 375 | |
cdd6c482 IM |
376 | static atomic_t nr_mmap_events __read_mostly; |
377 | static atomic_t nr_comm_events __read_mostly; | |
378 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 379 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 380 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 381 | |
108b02cf PZ |
382 | static LIST_HEAD(pmus); |
383 | static DEFINE_MUTEX(pmus_lock); | |
384 | static struct srcu_struct pmus_srcu; | |
385 | ||
0764771d | 386 | /* |
cdd6c482 | 387 | * perf event paranoia level: |
0fbdea19 IM |
388 | * -1 - not paranoid at all |
389 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 390 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 391 | * 2 - disallow kernel profiling for unpriv |
0764771d | 392 | */ |
0161028b | 393 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 394 | |
20443384 FW |
395 | /* Minimum for 512 kiB + 1 user control page */ |
396 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
397 | |
398 | /* | |
cdd6c482 | 399 | * max perf event sample rate |
df58ab24 | 400 | */ |
14c63f17 DH |
401 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
402 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
403 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
404 | ||
405 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
406 | ||
407 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
408 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
409 | ||
d9494cb4 PZ |
410 | static int perf_sample_allowed_ns __read_mostly = |
411 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 412 | |
18ab2cd3 | 413 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
414 | { |
415 | u64 tmp = perf_sample_period_ns; | |
416 | ||
417 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
418 | tmp = div_u64(tmp, 100); |
419 | if (!tmp) | |
420 | tmp = 1; | |
421 | ||
422 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 423 | } |
163ec435 | 424 | |
9e630205 SE |
425 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
426 | ||
163ec435 PZ |
427 | int perf_proc_update_handler(struct ctl_table *table, int write, |
428 | void __user *buffer, size_t *lenp, | |
429 | loff_t *ppos) | |
430 | { | |
723478c8 | 431 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
432 | |
433 | if (ret || !write) | |
434 | return ret; | |
435 | ||
ab7fdefb KL |
436 | /* |
437 | * If throttling is disabled don't allow the write: | |
438 | */ | |
439 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
440 | sysctl_perf_cpu_time_max_percent == 0) | |
441 | return -EINVAL; | |
442 | ||
163ec435 | 443 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
444 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
445 | update_perf_cpu_limits(); | |
446 | ||
447 | return 0; | |
448 | } | |
449 | ||
450 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
451 | ||
452 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
453 | void __user *buffer, size_t *lenp, | |
454 | loff_t *ppos) | |
455 | { | |
456 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
457 | ||
458 | if (ret || !write) | |
459 | return ret; | |
460 | ||
b303e7c1 PZ |
461 | if (sysctl_perf_cpu_time_max_percent == 100 || |
462 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
463 | printk(KERN_WARNING |
464 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
465 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
466 | } else { | |
467 | update_perf_cpu_limits(); | |
468 | } | |
163ec435 PZ |
469 | |
470 | return 0; | |
471 | } | |
1ccd1549 | 472 | |
14c63f17 DH |
473 | /* |
474 | * perf samples are done in some very critical code paths (NMIs). | |
475 | * If they take too much CPU time, the system can lock up and not | |
476 | * get any real work done. This will drop the sample rate when | |
477 | * we detect that events are taking too long. | |
478 | */ | |
479 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 480 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 481 | |
91a612ee PZ |
482 | static u64 __report_avg; |
483 | static u64 __report_allowed; | |
484 | ||
6a02ad66 | 485 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 486 | { |
0d87d7ec | 487 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
488 | "perf: interrupt took too long (%lld > %lld), lowering " |
489 | "kernel.perf_event_max_sample_rate to %d\n", | |
490 | __report_avg, __report_allowed, | |
491 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
492 | } |
493 | ||
494 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
495 | ||
496 | void perf_sample_event_took(u64 sample_len_ns) | |
497 | { | |
91a612ee PZ |
498 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
499 | u64 running_len; | |
500 | u64 avg_len; | |
501 | u32 max; | |
14c63f17 | 502 | |
91a612ee | 503 | if (max_len == 0) |
14c63f17 DH |
504 | return; |
505 | ||
91a612ee PZ |
506 | /* Decay the counter by 1 average sample. */ |
507 | running_len = __this_cpu_read(running_sample_length); | |
508 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
509 | running_len += sample_len_ns; | |
510 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
511 | |
512 | /* | |
91a612ee PZ |
513 | * Note: this will be biased artifically low until we have |
514 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
515 | * from having to maintain a count. |
516 | */ | |
91a612ee PZ |
517 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
518 | if (avg_len <= max_len) | |
14c63f17 DH |
519 | return; |
520 | ||
91a612ee PZ |
521 | __report_avg = avg_len; |
522 | __report_allowed = max_len; | |
14c63f17 | 523 | |
91a612ee PZ |
524 | /* |
525 | * Compute a throttle threshold 25% below the current duration. | |
526 | */ | |
527 | avg_len += avg_len / 4; | |
528 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
529 | if (avg_len < max) | |
530 | max /= (u32)avg_len; | |
531 | else | |
532 | max = 1; | |
14c63f17 | 533 | |
91a612ee PZ |
534 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
535 | WRITE_ONCE(max_samples_per_tick, max); | |
536 | ||
537 | sysctl_perf_event_sample_rate = max * HZ; | |
538 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 539 | |
cd578abb | 540 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 541 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 542 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 543 | __report_avg, __report_allowed, |
cd578abb PZ |
544 | sysctl_perf_event_sample_rate); |
545 | } | |
14c63f17 DH |
546 | } |
547 | ||
cdd6c482 | 548 | static atomic64_t perf_event_id; |
a96bbc16 | 549 | |
0b3fcf17 SE |
550 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
551 | enum event_type_t event_type); | |
552 | ||
553 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
554 | enum event_type_t event_type, |
555 | struct task_struct *task); | |
556 | ||
557 | static void update_context_time(struct perf_event_context *ctx); | |
558 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 559 | |
cdd6c482 | 560 | void __weak perf_event_print_debug(void) { } |
0793a61d | 561 | |
84c79910 | 562 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 563 | { |
84c79910 | 564 | return "pmu"; |
0793a61d TG |
565 | } |
566 | ||
0b3fcf17 SE |
567 | static inline u64 perf_clock(void) |
568 | { | |
569 | return local_clock(); | |
570 | } | |
571 | ||
34f43927 PZ |
572 | static inline u64 perf_event_clock(struct perf_event *event) |
573 | { | |
574 | return event->clock(); | |
575 | } | |
576 | ||
e5d1367f SE |
577 | #ifdef CONFIG_CGROUP_PERF |
578 | ||
e5d1367f SE |
579 | static inline bool |
580 | perf_cgroup_match(struct perf_event *event) | |
581 | { | |
582 | struct perf_event_context *ctx = event->ctx; | |
583 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
584 | ||
ef824fa1 TH |
585 | /* @event doesn't care about cgroup */ |
586 | if (!event->cgrp) | |
587 | return true; | |
588 | ||
589 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
590 | if (!cpuctx->cgrp) | |
591 | return false; | |
592 | ||
593 | /* | |
594 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
595 | * also enabled for all its descendant cgroups. If @cpuctx's | |
596 | * cgroup is a descendant of @event's (the test covers identity | |
597 | * case), it's a match. | |
598 | */ | |
599 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
600 | event->cgrp->css.cgroup); | |
e5d1367f SE |
601 | } |
602 | ||
e5d1367f SE |
603 | static inline void perf_detach_cgroup(struct perf_event *event) |
604 | { | |
4e2ba650 | 605 | css_put(&event->cgrp->css); |
e5d1367f SE |
606 | event->cgrp = NULL; |
607 | } | |
608 | ||
609 | static inline int is_cgroup_event(struct perf_event *event) | |
610 | { | |
611 | return event->cgrp != NULL; | |
612 | } | |
613 | ||
614 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
615 | { | |
616 | struct perf_cgroup_info *t; | |
617 | ||
618 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
619 | return t->time; | |
620 | } | |
621 | ||
622 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
623 | { | |
624 | struct perf_cgroup_info *info; | |
625 | u64 now; | |
626 | ||
627 | now = perf_clock(); | |
628 | ||
629 | info = this_cpu_ptr(cgrp->info); | |
630 | ||
631 | info->time += now - info->timestamp; | |
632 | info->timestamp = now; | |
633 | } | |
634 | ||
635 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
636 | { | |
637 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
638 | if (cgrp_out) | |
639 | __update_cgrp_time(cgrp_out); | |
640 | } | |
641 | ||
642 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
643 | { | |
3f7cce3c SE |
644 | struct perf_cgroup *cgrp; |
645 | ||
e5d1367f | 646 | /* |
3f7cce3c SE |
647 | * ensure we access cgroup data only when needed and |
648 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 649 | */ |
3f7cce3c | 650 | if (!is_cgroup_event(event)) |
e5d1367f SE |
651 | return; |
652 | ||
614e4c4e | 653 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
654 | /* |
655 | * Do not update time when cgroup is not active | |
656 | */ | |
657 | if (cgrp == event->cgrp) | |
658 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
659 | } |
660 | ||
661 | static inline void | |
3f7cce3c SE |
662 | perf_cgroup_set_timestamp(struct task_struct *task, |
663 | struct perf_event_context *ctx) | |
e5d1367f SE |
664 | { |
665 | struct perf_cgroup *cgrp; | |
666 | struct perf_cgroup_info *info; | |
667 | ||
3f7cce3c SE |
668 | /* |
669 | * ctx->lock held by caller | |
670 | * ensure we do not access cgroup data | |
671 | * unless we have the cgroup pinned (css_get) | |
672 | */ | |
673 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
674 | return; |
675 | ||
614e4c4e | 676 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 677 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 678 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
679 | } |
680 | ||
681 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
682 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
683 | ||
684 | /* | |
685 | * reschedule events based on the cgroup constraint of task. | |
686 | * | |
687 | * mode SWOUT : schedule out everything | |
688 | * mode SWIN : schedule in based on cgroup for next | |
689 | */ | |
18ab2cd3 | 690 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
691 | { |
692 | struct perf_cpu_context *cpuctx; | |
693 | struct pmu *pmu; | |
694 | unsigned long flags; | |
695 | ||
696 | /* | |
697 | * disable interrupts to avoid geting nr_cgroup | |
698 | * changes via __perf_event_disable(). Also | |
699 | * avoids preemption. | |
700 | */ | |
701 | local_irq_save(flags); | |
702 | ||
703 | /* | |
704 | * we reschedule only in the presence of cgroup | |
705 | * constrained events. | |
706 | */ | |
e5d1367f SE |
707 | |
708 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f | 709 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95cf59ea PZ |
710 | if (cpuctx->unique_pmu != pmu) |
711 | continue; /* ensure we process each cpuctx once */ | |
e5d1367f | 712 | |
e5d1367f SE |
713 | /* |
714 | * perf_cgroup_events says at least one | |
715 | * context on this CPU has cgroup events. | |
716 | * | |
717 | * ctx->nr_cgroups reports the number of cgroup | |
718 | * events for a context. | |
719 | */ | |
720 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
721 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
722 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
723 | |
724 | if (mode & PERF_CGROUP_SWOUT) { | |
725 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
726 | /* | |
727 | * must not be done before ctxswout due | |
728 | * to event_filter_match() in event_sched_out() | |
729 | */ | |
730 | cpuctx->cgrp = NULL; | |
731 | } | |
732 | ||
733 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 734 | WARN_ON_ONCE(cpuctx->cgrp); |
95cf59ea PZ |
735 | /* |
736 | * set cgrp before ctxsw in to allow | |
737 | * event_filter_match() to not have to pass | |
738 | * task around | |
614e4c4e SE |
739 | * we pass the cpuctx->ctx to perf_cgroup_from_task() |
740 | * because cgorup events are only per-cpu | |
e5d1367f | 741 | */ |
614e4c4e | 742 | cpuctx->cgrp = perf_cgroup_from_task(task, &cpuctx->ctx); |
e5d1367f SE |
743 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); |
744 | } | |
facc4307 PZ |
745 | perf_pmu_enable(cpuctx->ctx.pmu); |
746 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 747 | } |
e5d1367f SE |
748 | } |
749 | ||
e5d1367f SE |
750 | local_irq_restore(flags); |
751 | } | |
752 | ||
a8d757ef SE |
753 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
754 | struct task_struct *next) | |
e5d1367f | 755 | { |
a8d757ef SE |
756 | struct perf_cgroup *cgrp1; |
757 | struct perf_cgroup *cgrp2 = NULL; | |
758 | ||
ddaaf4e2 | 759 | rcu_read_lock(); |
a8d757ef SE |
760 | /* |
761 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
762 | * we do not need to pass the ctx here because we know |
763 | * we are holding the rcu lock | |
a8d757ef | 764 | */ |
614e4c4e | 765 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 766 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
767 | |
768 | /* | |
769 | * only schedule out current cgroup events if we know | |
770 | * that we are switching to a different cgroup. Otherwise, | |
771 | * do no touch the cgroup events. | |
772 | */ | |
773 | if (cgrp1 != cgrp2) | |
774 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
775 | |
776 | rcu_read_unlock(); | |
e5d1367f SE |
777 | } |
778 | ||
a8d757ef SE |
779 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
780 | struct task_struct *task) | |
e5d1367f | 781 | { |
a8d757ef SE |
782 | struct perf_cgroup *cgrp1; |
783 | struct perf_cgroup *cgrp2 = NULL; | |
784 | ||
ddaaf4e2 | 785 | rcu_read_lock(); |
a8d757ef SE |
786 | /* |
787 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
788 | * we do not need to pass the ctx here because we know |
789 | * we are holding the rcu lock | |
a8d757ef | 790 | */ |
614e4c4e | 791 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 792 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
793 | |
794 | /* | |
795 | * only need to schedule in cgroup events if we are changing | |
796 | * cgroup during ctxsw. Cgroup events were not scheduled | |
797 | * out of ctxsw out if that was not the case. | |
798 | */ | |
799 | if (cgrp1 != cgrp2) | |
800 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
801 | |
802 | rcu_read_unlock(); | |
e5d1367f SE |
803 | } |
804 | ||
805 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
806 | struct perf_event_attr *attr, | |
807 | struct perf_event *group_leader) | |
808 | { | |
809 | struct perf_cgroup *cgrp; | |
810 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
811 | struct fd f = fdget(fd); |
812 | int ret = 0; | |
e5d1367f | 813 | |
2903ff01 | 814 | if (!f.file) |
e5d1367f SE |
815 | return -EBADF; |
816 | ||
b583043e | 817 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 818 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
819 | if (IS_ERR(css)) { |
820 | ret = PTR_ERR(css); | |
821 | goto out; | |
822 | } | |
e5d1367f SE |
823 | |
824 | cgrp = container_of(css, struct perf_cgroup, css); | |
825 | event->cgrp = cgrp; | |
826 | ||
827 | /* | |
828 | * all events in a group must monitor | |
829 | * the same cgroup because a task belongs | |
830 | * to only one perf cgroup at a time | |
831 | */ | |
832 | if (group_leader && group_leader->cgrp != cgrp) { | |
833 | perf_detach_cgroup(event); | |
834 | ret = -EINVAL; | |
e5d1367f | 835 | } |
3db272c0 | 836 | out: |
2903ff01 | 837 | fdput(f); |
e5d1367f SE |
838 | return ret; |
839 | } | |
840 | ||
841 | static inline void | |
842 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
843 | { | |
844 | struct perf_cgroup_info *t; | |
845 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
846 | event->shadow_ctx_time = now - t->timestamp; | |
847 | } | |
848 | ||
849 | static inline void | |
850 | perf_cgroup_defer_enabled(struct perf_event *event) | |
851 | { | |
852 | /* | |
853 | * when the current task's perf cgroup does not match | |
854 | * the event's, we need to remember to call the | |
855 | * perf_mark_enable() function the first time a task with | |
856 | * a matching perf cgroup is scheduled in. | |
857 | */ | |
858 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
859 | event->cgrp_defer_enabled = 1; | |
860 | } | |
861 | ||
862 | static inline void | |
863 | perf_cgroup_mark_enabled(struct perf_event *event, | |
864 | struct perf_event_context *ctx) | |
865 | { | |
866 | struct perf_event *sub; | |
867 | u64 tstamp = perf_event_time(event); | |
868 | ||
869 | if (!event->cgrp_defer_enabled) | |
870 | return; | |
871 | ||
872 | event->cgrp_defer_enabled = 0; | |
873 | ||
874 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
875 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
876 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
877 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
878 | sub->cgrp_defer_enabled = 0; | |
879 | } | |
880 | } | |
881 | } | |
db4a8356 DCC |
882 | |
883 | /* | |
884 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
885 | * cleared when last cgroup event is removed. | |
886 | */ | |
887 | static inline void | |
888 | list_update_cgroup_event(struct perf_event *event, | |
889 | struct perf_event_context *ctx, bool add) | |
890 | { | |
891 | struct perf_cpu_context *cpuctx; | |
892 | ||
893 | if (!is_cgroup_event(event)) | |
894 | return; | |
895 | ||
896 | if (add && ctx->nr_cgroups++) | |
897 | return; | |
898 | else if (!add && --ctx->nr_cgroups) | |
899 | return; | |
900 | /* | |
901 | * Because cgroup events are always per-cpu events, | |
902 | * this will always be called from the right CPU. | |
903 | */ | |
904 | cpuctx = __get_cpu_context(ctx); | |
864c2357 | 905 | |
8fc31ce8 DCC |
906 | /* |
907 | * cpuctx->cgrp is NULL until a cgroup event is sched in or | |
908 | * ctx->nr_cgroup == 0 . | |
909 | */ | |
910 | if (add && perf_cgroup_from_task(current, ctx) == event->cgrp) | |
911 | cpuctx->cgrp = event->cgrp; | |
912 | else if (!add) | |
913 | cpuctx->cgrp = NULL; | |
db4a8356 DCC |
914 | } |
915 | ||
e5d1367f SE |
916 | #else /* !CONFIG_CGROUP_PERF */ |
917 | ||
918 | static inline bool | |
919 | perf_cgroup_match(struct perf_event *event) | |
920 | { | |
921 | return true; | |
922 | } | |
923 | ||
924 | static inline void perf_detach_cgroup(struct perf_event *event) | |
925 | {} | |
926 | ||
927 | static inline int is_cgroup_event(struct perf_event *event) | |
928 | { | |
929 | return 0; | |
930 | } | |
931 | ||
932 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
933 | { | |
934 | return 0; | |
935 | } | |
936 | ||
937 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
938 | { | |
939 | } | |
940 | ||
941 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
942 | { | |
943 | } | |
944 | ||
a8d757ef SE |
945 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
946 | struct task_struct *next) | |
e5d1367f SE |
947 | { |
948 | } | |
949 | ||
a8d757ef SE |
950 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
951 | struct task_struct *task) | |
e5d1367f SE |
952 | { |
953 | } | |
954 | ||
955 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
956 | struct perf_event_attr *attr, | |
957 | struct perf_event *group_leader) | |
958 | { | |
959 | return -EINVAL; | |
960 | } | |
961 | ||
962 | static inline void | |
3f7cce3c SE |
963 | perf_cgroup_set_timestamp(struct task_struct *task, |
964 | struct perf_event_context *ctx) | |
e5d1367f SE |
965 | { |
966 | } | |
967 | ||
968 | void | |
969 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
970 | { | |
971 | } | |
972 | ||
973 | static inline void | |
974 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
975 | { | |
976 | } | |
977 | ||
978 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
979 | { | |
980 | return 0; | |
981 | } | |
982 | ||
983 | static inline void | |
984 | perf_cgroup_defer_enabled(struct perf_event *event) | |
985 | { | |
986 | } | |
987 | ||
988 | static inline void | |
989 | perf_cgroup_mark_enabled(struct perf_event *event, | |
990 | struct perf_event_context *ctx) | |
991 | { | |
992 | } | |
db4a8356 DCC |
993 | |
994 | static inline void | |
995 | list_update_cgroup_event(struct perf_event *event, | |
996 | struct perf_event_context *ctx, bool add) | |
997 | { | |
998 | } | |
999 | ||
e5d1367f SE |
1000 | #endif |
1001 | ||
9e630205 SE |
1002 | /* |
1003 | * set default to be dependent on timer tick just | |
1004 | * like original code | |
1005 | */ | |
1006 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1007 | /* | |
1008 | * function must be called with interrupts disbled | |
1009 | */ | |
272325c4 | 1010 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1011 | { |
1012 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1013 | int rotations = 0; |
1014 | ||
1015 | WARN_ON(!irqs_disabled()); | |
1016 | ||
1017 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1018 | rotations = perf_rotate_context(cpuctx); |
1019 | ||
4cfafd30 PZ |
1020 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1021 | if (rotations) | |
9e630205 | 1022 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1023 | else |
1024 | cpuctx->hrtimer_active = 0; | |
1025 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1026 | |
4cfafd30 | 1027 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1028 | } |
1029 | ||
272325c4 | 1030 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1031 | { |
272325c4 | 1032 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1033 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1034 | u64 interval; |
9e630205 SE |
1035 | |
1036 | /* no multiplexing needed for SW PMU */ | |
1037 | if (pmu->task_ctx_nr == perf_sw_context) | |
1038 | return; | |
1039 | ||
62b85639 SE |
1040 | /* |
1041 | * check default is sane, if not set then force to | |
1042 | * default interval (1/tick) | |
1043 | */ | |
272325c4 PZ |
1044 | interval = pmu->hrtimer_interval_ms; |
1045 | if (interval < 1) | |
1046 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1047 | |
272325c4 | 1048 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1049 | |
4cfafd30 PZ |
1050 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1051 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1052 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1053 | } |
1054 | ||
272325c4 | 1055 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1056 | { |
272325c4 | 1057 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1058 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1059 | unsigned long flags; |
9e630205 SE |
1060 | |
1061 | /* not for SW PMU */ | |
1062 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1063 | return 0; |
9e630205 | 1064 | |
4cfafd30 PZ |
1065 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1066 | if (!cpuctx->hrtimer_active) { | |
1067 | cpuctx->hrtimer_active = 1; | |
1068 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1069 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1070 | } | |
1071 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1072 | |
272325c4 | 1073 | return 0; |
9e630205 SE |
1074 | } |
1075 | ||
33696fc0 | 1076 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1077 | { |
33696fc0 PZ |
1078 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1079 | if (!(*count)++) | |
1080 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1081 | } |
9e35ad38 | 1082 | |
33696fc0 | 1083 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1084 | { |
33696fc0 PZ |
1085 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1086 | if (!--(*count)) | |
1087 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1088 | } |
9e35ad38 | 1089 | |
2fde4f94 | 1090 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1091 | |
1092 | /* | |
2fde4f94 MR |
1093 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1094 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1095 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1096 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1097 | */ |
2fde4f94 | 1098 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1099 | { |
2fde4f94 | 1100 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1101 | |
e9d2b064 | 1102 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1103 | |
2fde4f94 MR |
1104 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1105 | ||
1106 | list_add(&ctx->active_ctx_list, head); | |
1107 | } | |
1108 | ||
1109 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1110 | { | |
1111 | WARN_ON(!irqs_disabled()); | |
1112 | ||
1113 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1114 | ||
1115 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1116 | } |
9e35ad38 | 1117 | |
cdd6c482 | 1118 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1119 | { |
e5289d4a | 1120 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1121 | } |
1122 | ||
4af57ef2 YZ |
1123 | static void free_ctx(struct rcu_head *head) |
1124 | { | |
1125 | struct perf_event_context *ctx; | |
1126 | ||
1127 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1128 | kfree(ctx->task_ctx_data); | |
1129 | kfree(ctx); | |
1130 | } | |
1131 | ||
cdd6c482 | 1132 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1133 | { |
564c2b21 PM |
1134 | if (atomic_dec_and_test(&ctx->refcount)) { |
1135 | if (ctx->parent_ctx) | |
1136 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1137 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1138 | put_task_struct(ctx->task); |
4af57ef2 | 1139 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1140 | } |
a63eaf34 PM |
1141 | } |
1142 | ||
f63a8daa PZ |
1143 | /* |
1144 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1145 | * perf_pmu_migrate_context() we need some magic. | |
1146 | * | |
1147 | * Those places that change perf_event::ctx will hold both | |
1148 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1149 | * | |
8b10c5e2 PZ |
1150 | * Lock ordering is by mutex address. There are two other sites where |
1151 | * perf_event_context::mutex nests and those are: | |
1152 | * | |
1153 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1154 | * perf_event_exit_event() |
1155 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1156 | * |
1157 | * - perf_event_init_context() [ parent, 0 ] | |
1158 | * inherit_task_group() | |
1159 | * inherit_group() | |
1160 | * inherit_event() | |
1161 | * perf_event_alloc() | |
1162 | * perf_init_event() | |
1163 | * perf_try_init_event() [ child , 1 ] | |
1164 | * | |
1165 | * While it appears there is an obvious deadlock here -- the parent and child | |
1166 | * nesting levels are inverted between the two. This is in fact safe because | |
1167 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1168 | * spawning task cannot (yet) exit. | |
1169 | * | |
1170 | * But remember that that these are parent<->child context relations, and | |
1171 | * migration does not affect children, therefore these two orderings should not | |
1172 | * interact. | |
f63a8daa PZ |
1173 | * |
1174 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1175 | * because the sys_perf_event_open() case will install a new event and break | |
1176 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1177 | * concerned with cpuctx and that doesn't have children. | |
1178 | * | |
1179 | * The places that change perf_event::ctx will issue: | |
1180 | * | |
1181 | * perf_remove_from_context(); | |
1182 | * synchronize_rcu(); | |
1183 | * perf_install_in_context(); | |
1184 | * | |
1185 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1186 | * quiesce the event, after which we can install it in the new location. This | |
1187 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1188 | * while in transit. Therefore all such accessors should also acquire | |
1189 | * perf_event_context::mutex to serialize against this. | |
1190 | * | |
1191 | * However; because event->ctx can change while we're waiting to acquire | |
1192 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1193 | * function. | |
1194 | * | |
1195 | * Lock order: | |
79c9ce57 | 1196 | * cred_guard_mutex |
f63a8daa PZ |
1197 | * task_struct::perf_event_mutex |
1198 | * perf_event_context::mutex | |
f63a8daa | 1199 | * perf_event::child_mutex; |
07c4a776 | 1200 | * perf_event_context::lock |
f63a8daa PZ |
1201 | * perf_event::mmap_mutex |
1202 | * mmap_sem | |
1203 | */ | |
a83fe28e PZ |
1204 | static struct perf_event_context * |
1205 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1206 | { |
1207 | struct perf_event_context *ctx; | |
1208 | ||
1209 | again: | |
1210 | rcu_read_lock(); | |
1211 | ctx = ACCESS_ONCE(event->ctx); | |
1212 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1213 | rcu_read_unlock(); | |
1214 | goto again; | |
1215 | } | |
1216 | rcu_read_unlock(); | |
1217 | ||
a83fe28e | 1218 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1219 | if (event->ctx != ctx) { |
1220 | mutex_unlock(&ctx->mutex); | |
1221 | put_ctx(ctx); | |
1222 | goto again; | |
1223 | } | |
1224 | ||
1225 | return ctx; | |
1226 | } | |
1227 | ||
a83fe28e PZ |
1228 | static inline struct perf_event_context * |
1229 | perf_event_ctx_lock(struct perf_event *event) | |
1230 | { | |
1231 | return perf_event_ctx_lock_nested(event, 0); | |
1232 | } | |
1233 | ||
f63a8daa PZ |
1234 | static void perf_event_ctx_unlock(struct perf_event *event, |
1235 | struct perf_event_context *ctx) | |
1236 | { | |
1237 | mutex_unlock(&ctx->mutex); | |
1238 | put_ctx(ctx); | |
1239 | } | |
1240 | ||
211de6eb PZ |
1241 | /* |
1242 | * This must be done under the ctx->lock, such as to serialize against | |
1243 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1244 | * calling scheduler related locks and ctx->lock nests inside those. | |
1245 | */ | |
1246 | static __must_check struct perf_event_context * | |
1247 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1248 | { |
211de6eb PZ |
1249 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1250 | ||
1251 | lockdep_assert_held(&ctx->lock); | |
1252 | ||
1253 | if (parent_ctx) | |
71a851b4 | 1254 | ctx->parent_ctx = NULL; |
5a3126d4 | 1255 | ctx->generation++; |
211de6eb PZ |
1256 | |
1257 | return parent_ctx; | |
71a851b4 PZ |
1258 | } |
1259 | ||
6844c09d ACM |
1260 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1261 | { | |
1262 | /* | |
1263 | * only top level events have the pid namespace they were created in | |
1264 | */ | |
1265 | if (event->parent) | |
1266 | event = event->parent; | |
1267 | ||
1268 | return task_tgid_nr_ns(p, event->ns); | |
1269 | } | |
1270 | ||
1271 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1272 | { | |
1273 | /* | |
1274 | * only top level events have the pid namespace they were created in | |
1275 | */ | |
1276 | if (event->parent) | |
1277 | event = event->parent; | |
1278 | ||
1279 | return task_pid_nr_ns(p, event->ns); | |
1280 | } | |
1281 | ||
7f453c24 | 1282 | /* |
cdd6c482 | 1283 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1284 | * to userspace. |
1285 | */ | |
cdd6c482 | 1286 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1287 | { |
cdd6c482 | 1288 | u64 id = event->id; |
7f453c24 | 1289 | |
cdd6c482 IM |
1290 | if (event->parent) |
1291 | id = event->parent->id; | |
7f453c24 PZ |
1292 | |
1293 | return id; | |
1294 | } | |
1295 | ||
25346b93 | 1296 | /* |
cdd6c482 | 1297 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1298 | * |
25346b93 PM |
1299 | * This has to cope with with the fact that until it is locked, |
1300 | * the context could get moved to another task. | |
1301 | */ | |
cdd6c482 | 1302 | static struct perf_event_context * |
8dc85d54 | 1303 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1304 | { |
cdd6c482 | 1305 | struct perf_event_context *ctx; |
25346b93 | 1306 | |
9ed6060d | 1307 | retry: |
058ebd0e PZ |
1308 | /* |
1309 | * One of the few rules of preemptible RCU is that one cannot do | |
1310 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1311 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1312 | * rcu_read_unlock_special(). |
1313 | * | |
1314 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1315 | * side critical section has interrupts disabled. |
058ebd0e | 1316 | */ |
2fd59077 | 1317 | local_irq_save(*flags); |
058ebd0e | 1318 | rcu_read_lock(); |
8dc85d54 | 1319 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1320 | if (ctx) { |
1321 | /* | |
1322 | * If this context is a clone of another, it might | |
1323 | * get swapped for another underneath us by | |
cdd6c482 | 1324 | * perf_event_task_sched_out, though the |
25346b93 PM |
1325 | * rcu_read_lock() protects us from any context |
1326 | * getting freed. Lock the context and check if it | |
1327 | * got swapped before we could get the lock, and retry | |
1328 | * if so. If we locked the right context, then it | |
1329 | * can't get swapped on us any more. | |
1330 | */ | |
2fd59077 | 1331 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1332 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1333 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1334 | rcu_read_unlock(); |
2fd59077 | 1335 | local_irq_restore(*flags); |
25346b93 PM |
1336 | goto retry; |
1337 | } | |
b49a9e7e | 1338 | |
63b6da39 PZ |
1339 | if (ctx->task == TASK_TOMBSTONE || |
1340 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1341 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1342 | ctx = NULL; |
828b6f0e PZ |
1343 | } else { |
1344 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1345 | } |
25346b93 PM |
1346 | } |
1347 | rcu_read_unlock(); | |
2fd59077 PM |
1348 | if (!ctx) |
1349 | local_irq_restore(*flags); | |
25346b93 PM |
1350 | return ctx; |
1351 | } | |
1352 | ||
1353 | /* | |
1354 | * Get the context for a task and increment its pin_count so it | |
1355 | * can't get swapped to another task. This also increments its | |
1356 | * reference count so that the context can't get freed. | |
1357 | */ | |
8dc85d54 PZ |
1358 | static struct perf_event_context * |
1359 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1360 | { |
cdd6c482 | 1361 | struct perf_event_context *ctx; |
25346b93 PM |
1362 | unsigned long flags; |
1363 | ||
8dc85d54 | 1364 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1365 | if (ctx) { |
1366 | ++ctx->pin_count; | |
e625cce1 | 1367 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1368 | } |
1369 | return ctx; | |
1370 | } | |
1371 | ||
cdd6c482 | 1372 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1373 | { |
1374 | unsigned long flags; | |
1375 | ||
e625cce1 | 1376 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1377 | --ctx->pin_count; |
e625cce1 | 1378 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1379 | } |
1380 | ||
f67218c3 PZ |
1381 | /* |
1382 | * Update the record of the current time in a context. | |
1383 | */ | |
1384 | static void update_context_time(struct perf_event_context *ctx) | |
1385 | { | |
1386 | u64 now = perf_clock(); | |
1387 | ||
1388 | ctx->time += now - ctx->timestamp; | |
1389 | ctx->timestamp = now; | |
1390 | } | |
1391 | ||
4158755d SE |
1392 | static u64 perf_event_time(struct perf_event *event) |
1393 | { | |
1394 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1395 | |
1396 | if (is_cgroup_event(event)) | |
1397 | return perf_cgroup_event_time(event); | |
1398 | ||
4158755d SE |
1399 | return ctx ? ctx->time : 0; |
1400 | } | |
1401 | ||
f67218c3 PZ |
1402 | /* |
1403 | * Update the total_time_enabled and total_time_running fields for a event. | |
1404 | */ | |
1405 | static void update_event_times(struct perf_event *event) | |
1406 | { | |
1407 | struct perf_event_context *ctx = event->ctx; | |
1408 | u64 run_end; | |
1409 | ||
3cbaa590 PZ |
1410 | lockdep_assert_held(&ctx->lock); |
1411 | ||
f67218c3 PZ |
1412 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1413 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1414 | return; | |
3cbaa590 | 1415 | |
e5d1367f SE |
1416 | /* |
1417 | * in cgroup mode, time_enabled represents | |
1418 | * the time the event was enabled AND active | |
1419 | * tasks were in the monitored cgroup. This is | |
1420 | * independent of the activity of the context as | |
1421 | * there may be a mix of cgroup and non-cgroup events. | |
1422 | * | |
1423 | * That is why we treat cgroup events differently | |
1424 | * here. | |
1425 | */ | |
1426 | if (is_cgroup_event(event)) | |
46cd6a7f | 1427 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1428 | else if (ctx->is_active) |
1429 | run_end = ctx->time; | |
acd1d7c1 PZ |
1430 | else |
1431 | run_end = event->tstamp_stopped; | |
1432 | ||
1433 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1434 | |
1435 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1436 | run_end = event->tstamp_stopped; | |
1437 | else | |
4158755d | 1438 | run_end = perf_event_time(event); |
f67218c3 PZ |
1439 | |
1440 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1441 | |
f67218c3 PZ |
1442 | } |
1443 | ||
96c21a46 PZ |
1444 | /* |
1445 | * Update total_time_enabled and total_time_running for all events in a group. | |
1446 | */ | |
1447 | static void update_group_times(struct perf_event *leader) | |
1448 | { | |
1449 | struct perf_event *event; | |
1450 | ||
1451 | update_event_times(leader); | |
1452 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1453 | update_event_times(event); | |
1454 | } | |
1455 | ||
889ff015 FW |
1456 | static struct list_head * |
1457 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1458 | { | |
1459 | if (event->attr.pinned) | |
1460 | return &ctx->pinned_groups; | |
1461 | else | |
1462 | return &ctx->flexible_groups; | |
1463 | } | |
1464 | ||
fccc714b | 1465 | /* |
cdd6c482 | 1466 | * Add a event from the lists for its context. |
fccc714b PZ |
1467 | * Must be called with ctx->mutex and ctx->lock held. |
1468 | */ | |
04289bb9 | 1469 | static void |
cdd6c482 | 1470 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1471 | { |
c994d613 PZ |
1472 | lockdep_assert_held(&ctx->lock); |
1473 | ||
8a49542c PZ |
1474 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1475 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1476 | |
1477 | /* | |
8a49542c PZ |
1478 | * If we're a stand alone event or group leader, we go to the context |
1479 | * list, group events are kept attached to the group so that | |
1480 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1481 | */ |
8a49542c | 1482 | if (event->group_leader == event) { |
889ff015 FW |
1483 | struct list_head *list; |
1484 | ||
4ff6a8de | 1485 | event->group_caps = event->event_caps; |
d6f962b5 | 1486 | |
889ff015 FW |
1487 | list = ctx_group_list(event, ctx); |
1488 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1489 | } |
592903cd | 1490 | |
db4a8356 | 1491 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1492 | |
cdd6c482 IM |
1493 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1494 | ctx->nr_events++; | |
1495 | if (event->attr.inherit_stat) | |
bfbd3381 | 1496 | ctx->nr_stat++; |
5a3126d4 PZ |
1497 | |
1498 | ctx->generation++; | |
04289bb9 IM |
1499 | } |
1500 | ||
0231bb53 JO |
1501 | /* |
1502 | * Initialize event state based on the perf_event_attr::disabled. | |
1503 | */ | |
1504 | static inline void perf_event__state_init(struct perf_event *event) | |
1505 | { | |
1506 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1507 | PERF_EVENT_STATE_INACTIVE; | |
1508 | } | |
1509 | ||
a723968c | 1510 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1511 | { |
1512 | int entry = sizeof(u64); /* value */ | |
1513 | int size = 0; | |
1514 | int nr = 1; | |
1515 | ||
1516 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1517 | size += sizeof(u64); | |
1518 | ||
1519 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1520 | size += sizeof(u64); | |
1521 | ||
1522 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1523 | entry += sizeof(u64); | |
1524 | ||
1525 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1526 | nr += nr_siblings; |
c320c7b7 ACM |
1527 | size += sizeof(u64); |
1528 | } | |
1529 | ||
1530 | size += entry * nr; | |
1531 | event->read_size = size; | |
1532 | } | |
1533 | ||
a723968c | 1534 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1535 | { |
1536 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1537 | u16 size = 0; |
1538 | ||
c320c7b7 ACM |
1539 | if (sample_type & PERF_SAMPLE_IP) |
1540 | size += sizeof(data->ip); | |
1541 | ||
6844c09d ACM |
1542 | if (sample_type & PERF_SAMPLE_ADDR) |
1543 | size += sizeof(data->addr); | |
1544 | ||
1545 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1546 | size += sizeof(data->period); | |
1547 | ||
c3feedf2 AK |
1548 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1549 | size += sizeof(data->weight); | |
1550 | ||
6844c09d ACM |
1551 | if (sample_type & PERF_SAMPLE_READ) |
1552 | size += event->read_size; | |
1553 | ||
d6be9ad6 SE |
1554 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1555 | size += sizeof(data->data_src.val); | |
1556 | ||
fdfbbd07 AK |
1557 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1558 | size += sizeof(data->txn); | |
1559 | ||
6844c09d ACM |
1560 | event->header_size = size; |
1561 | } | |
1562 | ||
a723968c PZ |
1563 | /* |
1564 | * Called at perf_event creation and when events are attached/detached from a | |
1565 | * group. | |
1566 | */ | |
1567 | static void perf_event__header_size(struct perf_event *event) | |
1568 | { | |
1569 | __perf_event_read_size(event, | |
1570 | event->group_leader->nr_siblings); | |
1571 | __perf_event_header_size(event, event->attr.sample_type); | |
1572 | } | |
1573 | ||
6844c09d ACM |
1574 | static void perf_event__id_header_size(struct perf_event *event) |
1575 | { | |
1576 | struct perf_sample_data *data; | |
1577 | u64 sample_type = event->attr.sample_type; | |
1578 | u16 size = 0; | |
1579 | ||
c320c7b7 ACM |
1580 | if (sample_type & PERF_SAMPLE_TID) |
1581 | size += sizeof(data->tid_entry); | |
1582 | ||
1583 | if (sample_type & PERF_SAMPLE_TIME) | |
1584 | size += sizeof(data->time); | |
1585 | ||
ff3d527c AH |
1586 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1587 | size += sizeof(data->id); | |
1588 | ||
c320c7b7 ACM |
1589 | if (sample_type & PERF_SAMPLE_ID) |
1590 | size += sizeof(data->id); | |
1591 | ||
1592 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1593 | size += sizeof(data->stream_id); | |
1594 | ||
1595 | if (sample_type & PERF_SAMPLE_CPU) | |
1596 | size += sizeof(data->cpu_entry); | |
1597 | ||
6844c09d | 1598 | event->id_header_size = size; |
c320c7b7 ACM |
1599 | } |
1600 | ||
a723968c PZ |
1601 | static bool perf_event_validate_size(struct perf_event *event) |
1602 | { | |
1603 | /* | |
1604 | * The values computed here will be over-written when we actually | |
1605 | * attach the event. | |
1606 | */ | |
1607 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1608 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1609 | perf_event__id_header_size(event); | |
1610 | ||
1611 | /* | |
1612 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1613 | * Conservative limit to allow for callchains and other variable fields. | |
1614 | */ | |
1615 | if (event->read_size + event->header_size + | |
1616 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1617 | return false; | |
1618 | ||
1619 | return true; | |
1620 | } | |
1621 | ||
8a49542c PZ |
1622 | static void perf_group_attach(struct perf_event *event) |
1623 | { | |
c320c7b7 | 1624 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1625 | |
a76a82a3 PZ |
1626 | lockdep_assert_held(&event->ctx->lock); |
1627 | ||
74c3337c PZ |
1628 | /* |
1629 | * We can have double attach due to group movement in perf_event_open. | |
1630 | */ | |
1631 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1632 | return; | |
1633 | ||
8a49542c PZ |
1634 | event->attach_state |= PERF_ATTACH_GROUP; |
1635 | ||
1636 | if (group_leader == event) | |
1637 | return; | |
1638 | ||
652884fe PZ |
1639 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1640 | ||
4ff6a8de | 1641 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1642 | |
1643 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1644 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1645 | |
1646 | perf_event__header_size(group_leader); | |
1647 | ||
1648 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1649 | perf_event__header_size(pos); | |
8a49542c PZ |
1650 | } |
1651 | ||
a63eaf34 | 1652 | /* |
cdd6c482 | 1653 | * Remove a event from the lists for its context. |
fccc714b | 1654 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1655 | */ |
04289bb9 | 1656 | static void |
cdd6c482 | 1657 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1658 | { |
652884fe PZ |
1659 | WARN_ON_ONCE(event->ctx != ctx); |
1660 | lockdep_assert_held(&ctx->lock); | |
1661 | ||
8a49542c PZ |
1662 | /* |
1663 | * We can have double detach due to exit/hot-unplug + close. | |
1664 | */ | |
1665 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1666 | return; |
8a49542c PZ |
1667 | |
1668 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1669 | ||
db4a8356 | 1670 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1671 | |
cdd6c482 IM |
1672 | ctx->nr_events--; |
1673 | if (event->attr.inherit_stat) | |
bfbd3381 | 1674 | ctx->nr_stat--; |
8bc20959 | 1675 | |
cdd6c482 | 1676 | list_del_rcu(&event->event_entry); |
04289bb9 | 1677 | |
8a49542c PZ |
1678 | if (event->group_leader == event) |
1679 | list_del_init(&event->group_entry); | |
5c148194 | 1680 | |
96c21a46 | 1681 | update_group_times(event); |
b2e74a26 SE |
1682 | |
1683 | /* | |
1684 | * If event was in error state, then keep it | |
1685 | * that way, otherwise bogus counts will be | |
1686 | * returned on read(). The only way to get out | |
1687 | * of error state is by explicit re-enabling | |
1688 | * of the event | |
1689 | */ | |
1690 | if (event->state > PERF_EVENT_STATE_OFF) | |
1691 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1692 | |
1693 | ctx->generation++; | |
050735b0 PZ |
1694 | } |
1695 | ||
8a49542c | 1696 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1697 | { |
1698 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1699 | struct list_head *list = NULL; |
1700 | ||
a76a82a3 PZ |
1701 | lockdep_assert_held(&event->ctx->lock); |
1702 | ||
8a49542c PZ |
1703 | /* |
1704 | * We can have double detach due to exit/hot-unplug + close. | |
1705 | */ | |
1706 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1707 | return; | |
1708 | ||
1709 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1710 | ||
1711 | /* | |
1712 | * If this is a sibling, remove it from its group. | |
1713 | */ | |
1714 | if (event->group_leader != event) { | |
1715 | list_del_init(&event->group_entry); | |
1716 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1717 | goto out; |
8a49542c PZ |
1718 | } |
1719 | ||
1720 | if (!list_empty(&event->group_entry)) | |
1721 | list = &event->group_entry; | |
2e2af50b | 1722 | |
04289bb9 | 1723 | /* |
cdd6c482 IM |
1724 | * If this was a group event with sibling events then |
1725 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1726 | * to whatever list we are on. |
04289bb9 | 1727 | */ |
cdd6c482 | 1728 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1729 | if (list) |
1730 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1731 | sibling->group_leader = sibling; |
d6f962b5 FW |
1732 | |
1733 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1734 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1735 | |
1736 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1737 | } |
c320c7b7 ACM |
1738 | |
1739 | out: | |
1740 | perf_event__header_size(event->group_leader); | |
1741 | ||
1742 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1743 | perf_event__header_size(tmp); | |
04289bb9 IM |
1744 | } |
1745 | ||
fadfe7be JO |
1746 | static bool is_orphaned_event(struct perf_event *event) |
1747 | { | |
a69b0ca4 | 1748 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1749 | } |
1750 | ||
2c81a647 | 1751 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1752 | { |
1753 | struct pmu *pmu = event->pmu; | |
1754 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1755 | } | |
1756 | ||
2c81a647 MR |
1757 | /* |
1758 | * Check whether we should attempt to schedule an event group based on | |
1759 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1760 | * potentially with a SW leader, so we must check all the filters, to | |
1761 | * determine whether a group is schedulable: | |
1762 | */ | |
1763 | static inline int pmu_filter_match(struct perf_event *event) | |
1764 | { | |
1765 | struct perf_event *child; | |
1766 | ||
1767 | if (!__pmu_filter_match(event)) | |
1768 | return 0; | |
1769 | ||
1770 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1771 | if (!__pmu_filter_match(child)) | |
1772 | return 0; | |
1773 | } | |
1774 | ||
1775 | return 1; | |
1776 | } | |
1777 | ||
fa66f07a SE |
1778 | static inline int |
1779 | event_filter_match(struct perf_event *event) | |
1780 | { | |
0b8f1e2e PZ |
1781 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1782 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1783 | } |
1784 | ||
9ffcfa6f SE |
1785 | static void |
1786 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1787 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1788 | struct perf_event_context *ctx) |
3b6f9e5c | 1789 | { |
4158755d | 1790 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1791 | u64 delta; |
652884fe PZ |
1792 | |
1793 | WARN_ON_ONCE(event->ctx != ctx); | |
1794 | lockdep_assert_held(&ctx->lock); | |
1795 | ||
fa66f07a SE |
1796 | /* |
1797 | * An event which could not be activated because of | |
1798 | * filter mismatch still needs to have its timings | |
1799 | * maintained, otherwise bogus information is return | |
1800 | * via read() for time_enabled, time_running: | |
1801 | */ | |
0b8f1e2e PZ |
1802 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1803 | !event_filter_match(event)) { | |
e5d1367f | 1804 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1805 | event->tstamp_running += delta; |
4158755d | 1806 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1807 | } |
1808 | ||
cdd6c482 | 1809 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1810 | return; |
3b6f9e5c | 1811 | |
44377277 AS |
1812 | perf_pmu_disable(event->pmu); |
1813 | ||
28a967c3 PZ |
1814 | event->tstamp_stopped = tstamp; |
1815 | event->pmu->del(event, 0); | |
1816 | event->oncpu = -1; | |
cdd6c482 IM |
1817 | event->state = PERF_EVENT_STATE_INACTIVE; |
1818 | if (event->pending_disable) { | |
1819 | event->pending_disable = 0; | |
1820 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1821 | } |
3b6f9e5c | 1822 | |
cdd6c482 | 1823 | if (!is_software_event(event)) |
3b6f9e5c | 1824 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1825 | if (!--ctx->nr_active) |
1826 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1827 | if (event->attr.freq && event->attr.sample_freq) |
1828 | ctx->nr_freq--; | |
cdd6c482 | 1829 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1830 | cpuctx->exclusive = 0; |
44377277 AS |
1831 | |
1832 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1833 | } |
1834 | ||
d859e29f | 1835 | static void |
cdd6c482 | 1836 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1837 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1838 | struct perf_event_context *ctx) |
d859e29f | 1839 | { |
cdd6c482 | 1840 | struct perf_event *event; |
fa66f07a | 1841 | int state = group_event->state; |
d859e29f | 1842 | |
3f005e7d MR |
1843 | perf_pmu_disable(ctx->pmu); |
1844 | ||
cdd6c482 | 1845 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1846 | |
1847 | /* | |
1848 | * Schedule out siblings (if any): | |
1849 | */ | |
cdd6c482 IM |
1850 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1851 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1852 | |
3f005e7d MR |
1853 | perf_pmu_enable(ctx->pmu); |
1854 | ||
fa66f07a | 1855 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1856 | cpuctx->exclusive = 0; |
1857 | } | |
1858 | ||
45a0e07a | 1859 | #define DETACH_GROUP 0x01UL |
0017960f | 1860 | |
0793a61d | 1861 | /* |
cdd6c482 | 1862 | * Cross CPU call to remove a performance event |
0793a61d | 1863 | * |
cdd6c482 | 1864 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1865 | * remove it from the context list. |
1866 | */ | |
fae3fde6 PZ |
1867 | static void |
1868 | __perf_remove_from_context(struct perf_event *event, | |
1869 | struct perf_cpu_context *cpuctx, | |
1870 | struct perf_event_context *ctx, | |
1871 | void *info) | |
0793a61d | 1872 | { |
45a0e07a | 1873 | unsigned long flags = (unsigned long)info; |
0793a61d | 1874 | |
cdd6c482 | 1875 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1876 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1877 | perf_group_detach(event); |
cdd6c482 | 1878 | list_del_event(event, ctx); |
39a43640 PZ |
1879 | |
1880 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1881 | ctx->is_active = 0; |
39a43640 PZ |
1882 | if (ctx->task) { |
1883 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1884 | cpuctx->task_ctx = NULL; | |
1885 | } | |
64ce3126 | 1886 | } |
0793a61d TG |
1887 | } |
1888 | ||
0793a61d | 1889 | /* |
cdd6c482 | 1890 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1891 | * |
cdd6c482 IM |
1892 | * If event->ctx is a cloned context, callers must make sure that |
1893 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1894 | * remains valid. This is OK when called from perf_release since |
1895 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1896 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1897 | * context has been detached from its task. |
0793a61d | 1898 | */ |
45a0e07a | 1899 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1900 | { |
a76a82a3 PZ |
1901 | struct perf_event_context *ctx = event->ctx; |
1902 | ||
1903 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 1904 | |
45a0e07a | 1905 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
1906 | |
1907 | /* | |
1908 | * The above event_function_call() can NO-OP when it hits | |
1909 | * TASK_TOMBSTONE. In that case we must already have been detached | |
1910 | * from the context (by perf_event_exit_event()) but the grouping | |
1911 | * might still be in-tact. | |
1912 | */ | |
1913 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
1914 | if ((flags & DETACH_GROUP) && | |
1915 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
1916 | /* | |
1917 | * Since in that case we cannot possibly be scheduled, simply | |
1918 | * detach now. | |
1919 | */ | |
1920 | raw_spin_lock_irq(&ctx->lock); | |
1921 | perf_group_detach(event); | |
1922 | raw_spin_unlock_irq(&ctx->lock); | |
1923 | } | |
0793a61d TG |
1924 | } |
1925 | ||
d859e29f | 1926 | /* |
cdd6c482 | 1927 | * Cross CPU call to disable a performance event |
d859e29f | 1928 | */ |
fae3fde6 PZ |
1929 | static void __perf_event_disable(struct perf_event *event, |
1930 | struct perf_cpu_context *cpuctx, | |
1931 | struct perf_event_context *ctx, | |
1932 | void *info) | |
7b648018 | 1933 | { |
fae3fde6 PZ |
1934 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1935 | return; | |
7b648018 | 1936 | |
fae3fde6 PZ |
1937 | update_context_time(ctx); |
1938 | update_cgrp_time_from_event(event); | |
1939 | update_group_times(event); | |
1940 | if (event == event->group_leader) | |
1941 | group_sched_out(event, cpuctx, ctx); | |
1942 | else | |
1943 | event_sched_out(event, cpuctx, ctx); | |
1944 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1945 | } |
1946 | ||
d859e29f | 1947 | /* |
cdd6c482 | 1948 | * Disable a event. |
c93f7669 | 1949 | * |
cdd6c482 IM |
1950 | * If event->ctx is a cloned context, callers must make sure that |
1951 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1952 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1953 | * perf_event_for_each_child or perf_event_for_each because they |
1954 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1955 | * goes to exit will block in perf_event_exit_event(). |
1956 | * | |
cdd6c482 | 1957 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1958 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1959 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1960 | */ |
f63a8daa | 1961 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1962 | { |
cdd6c482 | 1963 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1964 | |
e625cce1 | 1965 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1966 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1967 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1968 | return; |
53cfbf59 | 1969 | } |
e625cce1 | 1970 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1971 | |
fae3fde6 PZ |
1972 | event_function_call(event, __perf_event_disable, NULL); |
1973 | } | |
1974 | ||
1975 | void perf_event_disable_local(struct perf_event *event) | |
1976 | { | |
1977 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1978 | } |
f63a8daa PZ |
1979 | |
1980 | /* | |
1981 | * Strictly speaking kernel users cannot create groups and therefore this | |
1982 | * interface does not need the perf_event_ctx_lock() magic. | |
1983 | */ | |
1984 | void perf_event_disable(struct perf_event *event) | |
1985 | { | |
1986 | struct perf_event_context *ctx; | |
1987 | ||
1988 | ctx = perf_event_ctx_lock(event); | |
1989 | _perf_event_disable(event); | |
1990 | perf_event_ctx_unlock(event, ctx); | |
1991 | } | |
dcfce4a0 | 1992 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1993 | |
5aab90ce JO |
1994 | void perf_event_disable_inatomic(struct perf_event *event) |
1995 | { | |
1996 | event->pending_disable = 1; | |
1997 | irq_work_queue(&event->pending); | |
1998 | } | |
1999 | ||
e5d1367f SE |
2000 | static void perf_set_shadow_time(struct perf_event *event, |
2001 | struct perf_event_context *ctx, | |
2002 | u64 tstamp) | |
2003 | { | |
2004 | /* | |
2005 | * use the correct time source for the time snapshot | |
2006 | * | |
2007 | * We could get by without this by leveraging the | |
2008 | * fact that to get to this function, the caller | |
2009 | * has most likely already called update_context_time() | |
2010 | * and update_cgrp_time_xx() and thus both timestamp | |
2011 | * are identical (or very close). Given that tstamp is, | |
2012 | * already adjusted for cgroup, we could say that: | |
2013 | * tstamp - ctx->timestamp | |
2014 | * is equivalent to | |
2015 | * tstamp - cgrp->timestamp. | |
2016 | * | |
2017 | * Then, in perf_output_read(), the calculation would | |
2018 | * work with no changes because: | |
2019 | * - event is guaranteed scheduled in | |
2020 | * - no scheduled out in between | |
2021 | * - thus the timestamp would be the same | |
2022 | * | |
2023 | * But this is a bit hairy. | |
2024 | * | |
2025 | * So instead, we have an explicit cgroup call to remain | |
2026 | * within the time time source all along. We believe it | |
2027 | * is cleaner and simpler to understand. | |
2028 | */ | |
2029 | if (is_cgroup_event(event)) | |
2030 | perf_cgroup_set_shadow_time(event, tstamp); | |
2031 | else | |
2032 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
2033 | } | |
2034 | ||
4fe757dd PZ |
2035 | #define MAX_INTERRUPTS (~0ULL) |
2036 | ||
2037 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2038 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2039 | |
235c7fc7 | 2040 | static int |
9ffcfa6f | 2041 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2042 | struct perf_cpu_context *cpuctx, |
6e37738a | 2043 | struct perf_event_context *ctx) |
235c7fc7 | 2044 | { |
4158755d | 2045 | u64 tstamp = perf_event_time(event); |
44377277 | 2046 | int ret = 0; |
4158755d | 2047 | |
63342411 PZ |
2048 | lockdep_assert_held(&ctx->lock); |
2049 | ||
cdd6c482 | 2050 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2051 | return 0; |
2052 | ||
95ff4ca2 AS |
2053 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2054 | /* | |
2055 | * Order event::oncpu write to happen before the ACTIVE state | |
2056 | * is visible. | |
2057 | */ | |
2058 | smp_wmb(); | |
2059 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
2060 | |
2061 | /* | |
2062 | * Unthrottle events, since we scheduled we might have missed several | |
2063 | * ticks already, also for a heavily scheduling task there is little | |
2064 | * guarantee it'll get a tick in a timely manner. | |
2065 | */ | |
2066 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2067 | perf_log_throttle(event, 1); | |
2068 | event->hw.interrupts = 0; | |
2069 | } | |
2070 | ||
235c7fc7 IM |
2071 | /* |
2072 | * The new state must be visible before we turn it on in the hardware: | |
2073 | */ | |
2074 | smp_wmb(); | |
2075 | ||
44377277 AS |
2076 | perf_pmu_disable(event->pmu); |
2077 | ||
72f669c0 SL |
2078 | perf_set_shadow_time(event, ctx, tstamp); |
2079 | ||
ec0d7729 AS |
2080 | perf_log_itrace_start(event); |
2081 | ||
a4eaf7f1 | 2082 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
2083 | event->state = PERF_EVENT_STATE_INACTIVE; |
2084 | event->oncpu = -1; | |
44377277 AS |
2085 | ret = -EAGAIN; |
2086 | goto out; | |
235c7fc7 IM |
2087 | } |
2088 | ||
00a2916f PZ |
2089 | event->tstamp_running += tstamp - event->tstamp_stopped; |
2090 | ||
cdd6c482 | 2091 | if (!is_software_event(event)) |
3b6f9e5c | 2092 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2093 | if (!ctx->nr_active++) |
2094 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2095 | if (event->attr.freq && event->attr.sample_freq) |
2096 | ctx->nr_freq++; | |
235c7fc7 | 2097 | |
cdd6c482 | 2098 | if (event->attr.exclusive) |
3b6f9e5c PM |
2099 | cpuctx->exclusive = 1; |
2100 | ||
44377277 AS |
2101 | out: |
2102 | perf_pmu_enable(event->pmu); | |
2103 | ||
2104 | return ret; | |
235c7fc7 IM |
2105 | } |
2106 | ||
6751b71e | 2107 | static int |
cdd6c482 | 2108 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2109 | struct perf_cpu_context *cpuctx, |
6e37738a | 2110 | struct perf_event_context *ctx) |
6751b71e | 2111 | { |
6bde9b6c | 2112 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2113 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2114 | u64 now = ctx->time; |
2115 | bool simulate = false; | |
6751b71e | 2116 | |
cdd6c482 | 2117 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2118 | return 0; |
2119 | ||
fbbe0701 | 2120 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2121 | |
9ffcfa6f | 2122 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2123 | pmu->cancel_txn(pmu); |
272325c4 | 2124 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2125 | return -EAGAIN; |
90151c35 | 2126 | } |
6751b71e PM |
2127 | |
2128 | /* | |
2129 | * Schedule in siblings as one group (if any): | |
2130 | */ | |
cdd6c482 | 2131 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2132 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2133 | partial_group = event; |
6751b71e PM |
2134 | goto group_error; |
2135 | } | |
2136 | } | |
2137 | ||
9ffcfa6f | 2138 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2139 | return 0; |
9ffcfa6f | 2140 | |
6751b71e PM |
2141 | group_error: |
2142 | /* | |
2143 | * Groups can be scheduled in as one unit only, so undo any | |
2144 | * partial group before returning: | |
d7842da4 SE |
2145 | * The events up to the failed event are scheduled out normally, |
2146 | * tstamp_stopped will be updated. | |
2147 | * | |
2148 | * The failed events and the remaining siblings need to have | |
2149 | * their timings updated as if they had gone thru event_sched_in() | |
2150 | * and event_sched_out(). This is required to get consistent timings | |
2151 | * across the group. This also takes care of the case where the group | |
2152 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2153 | * the time the event was actually stopped, such that time delta | |
2154 | * calculation in update_event_times() is correct. | |
6751b71e | 2155 | */ |
cdd6c482 IM |
2156 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2157 | if (event == partial_group) | |
d7842da4 SE |
2158 | simulate = true; |
2159 | ||
2160 | if (simulate) { | |
2161 | event->tstamp_running += now - event->tstamp_stopped; | |
2162 | event->tstamp_stopped = now; | |
2163 | } else { | |
2164 | event_sched_out(event, cpuctx, ctx); | |
2165 | } | |
6751b71e | 2166 | } |
9ffcfa6f | 2167 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2168 | |
ad5133b7 | 2169 | pmu->cancel_txn(pmu); |
90151c35 | 2170 | |
272325c4 | 2171 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2172 | |
6751b71e PM |
2173 | return -EAGAIN; |
2174 | } | |
2175 | ||
3b6f9e5c | 2176 | /* |
cdd6c482 | 2177 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2178 | */ |
cdd6c482 | 2179 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2180 | struct perf_cpu_context *cpuctx, |
2181 | int can_add_hw) | |
2182 | { | |
2183 | /* | |
cdd6c482 | 2184 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2185 | */ |
4ff6a8de | 2186 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2187 | return 1; |
2188 | /* | |
2189 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2190 | * events can go on. |
3b6f9e5c PM |
2191 | */ |
2192 | if (cpuctx->exclusive) | |
2193 | return 0; | |
2194 | /* | |
2195 | * If this group is exclusive and there are already | |
cdd6c482 | 2196 | * events on the CPU, it can't go on. |
3b6f9e5c | 2197 | */ |
cdd6c482 | 2198 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2199 | return 0; |
2200 | /* | |
2201 | * Otherwise, try to add it if all previous groups were able | |
2202 | * to go on. | |
2203 | */ | |
2204 | return can_add_hw; | |
2205 | } | |
2206 | ||
cdd6c482 IM |
2207 | static void add_event_to_ctx(struct perf_event *event, |
2208 | struct perf_event_context *ctx) | |
53cfbf59 | 2209 | { |
4158755d SE |
2210 | u64 tstamp = perf_event_time(event); |
2211 | ||
cdd6c482 | 2212 | list_add_event(event, ctx); |
8a49542c | 2213 | perf_group_attach(event); |
4158755d SE |
2214 | event->tstamp_enabled = tstamp; |
2215 | event->tstamp_running = tstamp; | |
2216 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2217 | } |
2218 | ||
bd2afa49 PZ |
2219 | static void ctx_sched_out(struct perf_event_context *ctx, |
2220 | struct perf_cpu_context *cpuctx, | |
2221 | enum event_type_t event_type); | |
2c29ef0f PZ |
2222 | static void |
2223 | ctx_sched_in(struct perf_event_context *ctx, | |
2224 | struct perf_cpu_context *cpuctx, | |
2225 | enum event_type_t event_type, | |
2226 | struct task_struct *task); | |
fe4b04fa | 2227 | |
bd2afa49 PZ |
2228 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
2229 | struct perf_event_context *ctx) | |
2230 | { | |
2231 | if (!cpuctx->task_ctx) | |
2232 | return; | |
2233 | ||
2234 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2235 | return; | |
2236 | ||
2237 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); | |
2238 | } | |
2239 | ||
dce5855b PZ |
2240 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2241 | struct perf_event_context *ctx, | |
2242 | struct task_struct *task) | |
2243 | { | |
2244 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2245 | if (ctx) | |
2246 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2247 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2248 | if (ctx) | |
2249 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2250 | } | |
2251 | ||
3e349507 PZ |
2252 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
2253 | struct perf_event_context *task_ctx) | |
0017960f | 2254 | { |
3e349507 PZ |
2255 | perf_pmu_disable(cpuctx->ctx.pmu); |
2256 | if (task_ctx) | |
2257 | task_ctx_sched_out(cpuctx, task_ctx); | |
2258 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
2259 | perf_event_sched_in(cpuctx, task_ctx, current); | |
2260 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2261 | } |
2262 | ||
0793a61d | 2263 | /* |
cdd6c482 | 2264 | * Cross CPU call to install and enable a performance event |
682076ae | 2265 | * |
a096309b PZ |
2266 | * Very similar to remote_function() + event_function() but cannot assume that |
2267 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2268 | */ |
fe4b04fa | 2269 | static int __perf_install_in_context(void *info) |
0793a61d | 2270 | { |
a096309b PZ |
2271 | struct perf_event *event = info; |
2272 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2273 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2274 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2275 | bool reprogram = true; |
a096309b | 2276 | int ret = 0; |
0793a61d | 2277 | |
63b6da39 | 2278 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2279 | if (ctx->task) { |
b58f6b0d PZ |
2280 | raw_spin_lock(&ctx->lock); |
2281 | task_ctx = ctx; | |
a096309b | 2282 | |
63cae12b | 2283 | reprogram = (ctx->task == current); |
b58f6b0d | 2284 | |
39a43640 | 2285 | /* |
63cae12b PZ |
2286 | * If the task is running, it must be running on this CPU, |
2287 | * otherwise we cannot reprogram things. | |
2288 | * | |
2289 | * If its not running, we don't care, ctx->lock will | |
2290 | * serialize against it becoming runnable. | |
39a43640 | 2291 | */ |
63cae12b PZ |
2292 | if (task_curr(ctx->task) && !reprogram) { |
2293 | ret = -ESRCH; | |
2294 | goto unlock; | |
2295 | } | |
a096309b | 2296 | |
63cae12b | 2297 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2298 | } else if (task_ctx) { |
2299 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2300 | } |
b58f6b0d | 2301 | |
63cae12b | 2302 | if (reprogram) { |
a096309b PZ |
2303 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2304 | add_event_to_ctx(event, ctx); | |
2305 | ctx_resched(cpuctx, task_ctx); | |
2306 | } else { | |
2307 | add_event_to_ctx(event, ctx); | |
2308 | } | |
2309 | ||
63b6da39 | 2310 | unlock: |
2c29ef0f | 2311 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2312 | |
a096309b | 2313 | return ret; |
0793a61d TG |
2314 | } |
2315 | ||
2316 | /* | |
a096309b PZ |
2317 | * Attach a performance event to a context. |
2318 | * | |
2319 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2320 | */ |
2321 | static void | |
cdd6c482 IM |
2322 | perf_install_in_context(struct perf_event_context *ctx, |
2323 | struct perf_event *event, | |
0793a61d TG |
2324 | int cpu) |
2325 | { | |
a096309b | 2326 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2327 | |
fe4b04fa PZ |
2328 | lockdep_assert_held(&ctx->mutex); |
2329 | ||
0cda4c02 YZ |
2330 | if (event->cpu != -1) |
2331 | event->cpu = cpu; | |
c3f00c70 | 2332 | |
0b8f1e2e PZ |
2333 | /* |
2334 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2335 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2336 | */ | |
2337 | smp_store_release(&event->ctx, ctx); | |
2338 | ||
a096309b PZ |
2339 | if (!task) { |
2340 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2341 | return; | |
2342 | } | |
2343 | ||
2344 | /* | |
2345 | * Should not happen, we validate the ctx is still alive before calling. | |
2346 | */ | |
2347 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2348 | return; | |
2349 | ||
39a43640 PZ |
2350 | /* |
2351 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2352 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2353 | * |
2354 | * Instead we use task_curr(), which tells us if the task is running. | |
2355 | * However, since we use task_curr() outside of rq::lock, we can race | |
2356 | * against the actual state. This means the result can be wrong. | |
2357 | * | |
2358 | * If we get a false positive, we retry, this is harmless. | |
2359 | * | |
2360 | * If we get a false negative, things are complicated. If we are after | |
2361 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2362 | * value must be correct. If we're before, it doesn't matter since | |
2363 | * perf_event_context_sched_in() will program the counter. | |
2364 | * | |
2365 | * However, this hinges on the remote context switch having observed | |
2366 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2367 | * ctx::lock in perf_event_context_sched_in(). | |
2368 | * | |
2369 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2370 | * we know any future context switch of task must see the | |
2371 | * perf_event_ctpx[] store. | |
39a43640 | 2372 | */ |
63cae12b | 2373 | |
63b6da39 | 2374 | /* |
63cae12b PZ |
2375 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2376 | * task_cpu() load, such that if the IPI then does not find the task | |
2377 | * running, a future context switch of that task must observe the | |
2378 | * store. | |
63b6da39 | 2379 | */ |
63cae12b PZ |
2380 | smp_mb(); |
2381 | again: | |
2382 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2383 | return; |
2384 | ||
2385 | raw_spin_lock_irq(&ctx->lock); | |
2386 | task = ctx->task; | |
84c4e620 | 2387 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2388 | /* |
2389 | * Cannot happen because we already checked above (which also | |
2390 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2391 | * against perf_event_exit_task_context(). | |
2392 | */ | |
63b6da39 PZ |
2393 | raw_spin_unlock_irq(&ctx->lock); |
2394 | return; | |
2395 | } | |
39a43640 | 2396 | /* |
63cae12b PZ |
2397 | * If the task is not running, ctx->lock will avoid it becoming so, |
2398 | * thus we can safely install the event. | |
39a43640 | 2399 | */ |
63cae12b PZ |
2400 | if (task_curr(task)) { |
2401 | raw_spin_unlock_irq(&ctx->lock); | |
2402 | goto again; | |
2403 | } | |
2404 | add_event_to_ctx(event, ctx); | |
2405 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2406 | } |
2407 | ||
fa289bec | 2408 | /* |
cdd6c482 | 2409 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2410 | * Enabling the leader of a group effectively enables all |
2411 | * the group members that aren't explicitly disabled, so we | |
2412 | * have to update their ->tstamp_enabled also. | |
2413 | * Note: this works for group members as well as group leaders | |
2414 | * since the non-leader members' sibling_lists will be empty. | |
2415 | */ | |
1d9b482e | 2416 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2417 | { |
cdd6c482 | 2418 | struct perf_event *sub; |
4158755d | 2419 | u64 tstamp = perf_event_time(event); |
fa289bec | 2420 | |
cdd6c482 | 2421 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2422 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2423 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2424 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2425 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2426 | } |
fa289bec PM |
2427 | } |
2428 | ||
d859e29f | 2429 | /* |
cdd6c482 | 2430 | * Cross CPU call to enable a performance event |
d859e29f | 2431 | */ |
fae3fde6 PZ |
2432 | static void __perf_event_enable(struct perf_event *event, |
2433 | struct perf_cpu_context *cpuctx, | |
2434 | struct perf_event_context *ctx, | |
2435 | void *info) | |
04289bb9 | 2436 | { |
cdd6c482 | 2437 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2438 | struct perf_event_context *task_ctx; |
04289bb9 | 2439 | |
6e801e01 PZ |
2440 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2441 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2442 | return; |
3cbed429 | 2443 | |
bd2afa49 PZ |
2444 | if (ctx->is_active) |
2445 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2446 | ||
1d9b482e | 2447 | __perf_event_mark_enabled(event); |
04289bb9 | 2448 | |
fae3fde6 PZ |
2449 | if (!ctx->is_active) |
2450 | return; | |
2451 | ||
e5d1367f | 2452 | if (!event_filter_match(event)) { |
bd2afa49 | 2453 | if (is_cgroup_event(event)) |
e5d1367f | 2454 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2455 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2456 | return; |
e5d1367f | 2457 | } |
f4c4176f | 2458 | |
04289bb9 | 2459 | /* |
cdd6c482 | 2460 | * If the event is in a group and isn't the group leader, |
d859e29f | 2461 | * then don't put it on unless the group is on. |
04289bb9 | 2462 | */ |
bd2afa49 PZ |
2463 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2464 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2465 | return; |
bd2afa49 | 2466 | } |
fe4b04fa | 2467 | |
fae3fde6 PZ |
2468 | task_ctx = cpuctx->task_ctx; |
2469 | if (ctx->task) | |
2470 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2471 | |
fae3fde6 | 2472 | ctx_resched(cpuctx, task_ctx); |
7b648018 PZ |
2473 | } |
2474 | ||
d859e29f | 2475 | /* |
cdd6c482 | 2476 | * Enable a event. |
c93f7669 | 2477 | * |
cdd6c482 IM |
2478 | * If event->ctx is a cloned context, callers must make sure that |
2479 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2480 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2481 | * perf_event_for_each_child or perf_event_for_each as described |
2482 | * for perf_event_disable. | |
d859e29f | 2483 | */ |
f63a8daa | 2484 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2485 | { |
cdd6c482 | 2486 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2487 | |
7b648018 | 2488 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2489 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2490 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2491 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2492 | return; |
2493 | } | |
2494 | ||
d859e29f | 2495 | /* |
cdd6c482 | 2496 | * If the event is in error state, clear that first. |
7b648018 PZ |
2497 | * |
2498 | * That way, if we see the event in error state below, we know that it | |
2499 | * has gone back into error state, as distinct from the task having | |
2500 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2501 | */ |
cdd6c482 IM |
2502 | if (event->state == PERF_EVENT_STATE_ERROR) |
2503 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2504 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2505 | |
fae3fde6 | 2506 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2507 | } |
f63a8daa PZ |
2508 | |
2509 | /* | |
2510 | * See perf_event_disable(); | |
2511 | */ | |
2512 | void perf_event_enable(struct perf_event *event) | |
2513 | { | |
2514 | struct perf_event_context *ctx; | |
2515 | ||
2516 | ctx = perf_event_ctx_lock(event); | |
2517 | _perf_event_enable(event); | |
2518 | perf_event_ctx_unlock(event, ctx); | |
2519 | } | |
dcfce4a0 | 2520 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2521 | |
375637bc AS |
2522 | struct stop_event_data { |
2523 | struct perf_event *event; | |
2524 | unsigned int restart; | |
2525 | }; | |
2526 | ||
95ff4ca2 AS |
2527 | static int __perf_event_stop(void *info) |
2528 | { | |
375637bc AS |
2529 | struct stop_event_data *sd = info; |
2530 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2531 | |
375637bc | 2532 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2533 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2534 | return 0; | |
2535 | ||
2536 | /* matches smp_wmb() in event_sched_in() */ | |
2537 | smp_rmb(); | |
2538 | ||
2539 | /* | |
2540 | * There is a window with interrupts enabled before we get here, | |
2541 | * so we need to check again lest we try to stop another CPU's event. | |
2542 | */ | |
2543 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2544 | return -EAGAIN; | |
2545 | ||
2546 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2547 | ||
375637bc AS |
2548 | /* |
2549 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2550 | * but it is only used for events with AUX ring buffer, and such | |
2551 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2552 | * see comments in perf_aux_output_begin(). | |
2553 | * | |
2554 | * Since this is happening on a event-local CPU, no trace is lost | |
2555 | * while restarting. | |
2556 | */ | |
2557 | if (sd->restart) | |
c9bbdd48 | 2558 | event->pmu->start(event, 0); |
375637bc | 2559 | |
95ff4ca2 AS |
2560 | return 0; |
2561 | } | |
2562 | ||
767ae086 | 2563 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2564 | { |
2565 | struct stop_event_data sd = { | |
2566 | .event = event, | |
767ae086 | 2567 | .restart = restart, |
375637bc AS |
2568 | }; |
2569 | int ret = 0; | |
2570 | ||
2571 | do { | |
2572 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2573 | return 0; | |
2574 | ||
2575 | /* matches smp_wmb() in event_sched_in() */ | |
2576 | smp_rmb(); | |
2577 | ||
2578 | /* | |
2579 | * We only want to restart ACTIVE events, so if the event goes | |
2580 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2581 | * fall through with ret==-ENXIO. | |
2582 | */ | |
2583 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2584 | __perf_event_stop, &sd); | |
2585 | } while (ret == -EAGAIN); | |
2586 | ||
2587 | return ret; | |
2588 | } | |
2589 | ||
2590 | /* | |
2591 | * In order to contain the amount of racy and tricky in the address filter | |
2592 | * configuration management, it is a two part process: | |
2593 | * | |
2594 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2595 | * we update the addresses of corresponding vmas in | |
2596 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2597 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2598 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2599 | * if the generation has changed since the previous call. | |
2600 | * | |
2601 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2602 | * | |
2603 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2604 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2605 | * ioctl; | |
2606 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2607 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2608 | * for reading; | |
2609 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2610 | * of exec. | |
2611 | */ | |
2612 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2613 | { | |
2614 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2615 | ||
2616 | if (!has_addr_filter(event)) | |
2617 | return; | |
2618 | ||
2619 | raw_spin_lock(&ifh->lock); | |
2620 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2621 | event->pmu->addr_filters_sync(event); | |
2622 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2623 | } | |
2624 | raw_spin_unlock(&ifh->lock); | |
2625 | } | |
2626 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2627 | ||
f63a8daa | 2628 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2629 | { |
2023b359 | 2630 | /* |
cdd6c482 | 2631 | * not supported on inherited events |
2023b359 | 2632 | */ |
2e939d1d | 2633 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2634 | return -EINVAL; |
2635 | ||
cdd6c482 | 2636 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2637 | _perf_event_enable(event); |
2023b359 PZ |
2638 | |
2639 | return 0; | |
79f14641 | 2640 | } |
f63a8daa PZ |
2641 | |
2642 | /* | |
2643 | * See perf_event_disable() | |
2644 | */ | |
2645 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2646 | { | |
2647 | struct perf_event_context *ctx; | |
2648 | int ret; | |
2649 | ||
2650 | ctx = perf_event_ctx_lock(event); | |
2651 | ret = _perf_event_refresh(event, refresh); | |
2652 | perf_event_ctx_unlock(event, ctx); | |
2653 | ||
2654 | return ret; | |
2655 | } | |
26ca5c11 | 2656 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2657 | |
5b0311e1 FW |
2658 | static void ctx_sched_out(struct perf_event_context *ctx, |
2659 | struct perf_cpu_context *cpuctx, | |
2660 | enum event_type_t event_type) | |
235c7fc7 | 2661 | { |
db24d33e | 2662 | int is_active = ctx->is_active; |
c994d613 | 2663 | struct perf_event *event; |
235c7fc7 | 2664 | |
c994d613 | 2665 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2666 | |
39a43640 PZ |
2667 | if (likely(!ctx->nr_events)) { |
2668 | /* | |
2669 | * See __perf_remove_from_context(). | |
2670 | */ | |
2671 | WARN_ON_ONCE(ctx->is_active); | |
2672 | if (ctx->task) | |
2673 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2674 | return; |
39a43640 PZ |
2675 | } |
2676 | ||
db24d33e | 2677 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2678 | if (!(ctx->is_active & EVENT_ALL)) |
2679 | ctx->is_active = 0; | |
2680 | ||
63e30d3e PZ |
2681 | if (ctx->task) { |
2682 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2683 | if (!ctx->is_active) | |
2684 | cpuctx->task_ctx = NULL; | |
2685 | } | |
facc4307 | 2686 | |
8fdc6539 PZ |
2687 | /* |
2688 | * Always update time if it was set; not only when it changes. | |
2689 | * Otherwise we can 'forget' to update time for any but the last | |
2690 | * context we sched out. For example: | |
2691 | * | |
2692 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2693 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2694 | * | |
2695 | * would only update time for the pinned events. | |
2696 | */ | |
3cbaa590 PZ |
2697 | if (is_active & EVENT_TIME) { |
2698 | /* update (and stop) ctx time */ | |
2699 | update_context_time(ctx); | |
2700 | update_cgrp_time_from_cpuctx(cpuctx); | |
2701 | } | |
2702 | ||
8fdc6539 PZ |
2703 | is_active ^= ctx->is_active; /* changed bits */ |
2704 | ||
3cbaa590 | 2705 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2706 | return; |
5b0311e1 | 2707 | |
075e0b00 | 2708 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2709 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2710 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2711 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2712 | } |
889ff015 | 2713 | |
3cbaa590 | 2714 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2715 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2716 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2717 | } |
1b9a644f | 2718 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2719 | } |
2720 | ||
564c2b21 | 2721 | /* |
5a3126d4 PZ |
2722 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2723 | * cloned from the same version of the same context. | |
2724 | * | |
2725 | * Equivalence is measured using a generation number in the context that is | |
2726 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2727 | * and list_del_event(). | |
564c2b21 | 2728 | */ |
cdd6c482 IM |
2729 | static int context_equiv(struct perf_event_context *ctx1, |
2730 | struct perf_event_context *ctx2) | |
564c2b21 | 2731 | { |
211de6eb PZ |
2732 | lockdep_assert_held(&ctx1->lock); |
2733 | lockdep_assert_held(&ctx2->lock); | |
2734 | ||
5a3126d4 PZ |
2735 | /* Pinning disables the swap optimization */ |
2736 | if (ctx1->pin_count || ctx2->pin_count) | |
2737 | return 0; | |
2738 | ||
2739 | /* If ctx1 is the parent of ctx2 */ | |
2740 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2741 | return 1; | |
2742 | ||
2743 | /* If ctx2 is the parent of ctx1 */ | |
2744 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2745 | return 1; | |
2746 | ||
2747 | /* | |
2748 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2749 | * hierarchy, see perf_event_init_context(). | |
2750 | */ | |
2751 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2752 | ctx1->parent_gen == ctx2->parent_gen) | |
2753 | return 1; | |
2754 | ||
2755 | /* Unmatched */ | |
2756 | return 0; | |
564c2b21 PM |
2757 | } |
2758 | ||
cdd6c482 IM |
2759 | static void __perf_event_sync_stat(struct perf_event *event, |
2760 | struct perf_event *next_event) | |
bfbd3381 PZ |
2761 | { |
2762 | u64 value; | |
2763 | ||
cdd6c482 | 2764 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2765 | return; |
2766 | ||
2767 | /* | |
cdd6c482 | 2768 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2769 | * because we're in the middle of a context switch and have IRQs |
2770 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2771 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2772 | * don't need to use it. |
2773 | */ | |
cdd6c482 IM |
2774 | switch (event->state) { |
2775 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2776 | event->pmu->read(event); |
2777 | /* fall-through */ | |
bfbd3381 | 2778 | |
cdd6c482 IM |
2779 | case PERF_EVENT_STATE_INACTIVE: |
2780 | update_event_times(event); | |
bfbd3381 PZ |
2781 | break; |
2782 | ||
2783 | default: | |
2784 | break; | |
2785 | } | |
2786 | ||
2787 | /* | |
cdd6c482 | 2788 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2789 | * values when we flip the contexts. |
2790 | */ | |
e7850595 PZ |
2791 | value = local64_read(&next_event->count); |
2792 | value = local64_xchg(&event->count, value); | |
2793 | local64_set(&next_event->count, value); | |
bfbd3381 | 2794 | |
cdd6c482 IM |
2795 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2796 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2797 | |
bfbd3381 | 2798 | /* |
19d2e755 | 2799 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2800 | */ |
cdd6c482 IM |
2801 | perf_event_update_userpage(event); |
2802 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2803 | } |
2804 | ||
cdd6c482 IM |
2805 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2806 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2807 | { |
cdd6c482 | 2808 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2809 | |
2810 | if (!ctx->nr_stat) | |
2811 | return; | |
2812 | ||
02ffdbc8 PZ |
2813 | update_context_time(ctx); |
2814 | ||
cdd6c482 IM |
2815 | event = list_first_entry(&ctx->event_list, |
2816 | struct perf_event, event_entry); | |
bfbd3381 | 2817 | |
cdd6c482 IM |
2818 | next_event = list_first_entry(&next_ctx->event_list, |
2819 | struct perf_event, event_entry); | |
bfbd3381 | 2820 | |
cdd6c482 IM |
2821 | while (&event->event_entry != &ctx->event_list && |
2822 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2823 | |
cdd6c482 | 2824 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2825 | |
cdd6c482 IM |
2826 | event = list_next_entry(event, event_entry); |
2827 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2828 | } |
2829 | } | |
2830 | ||
fe4b04fa PZ |
2831 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2832 | struct task_struct *next) | |
0793a61d | 2833 | { |
8dc85d54 | 2834 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2835 | struct perf_event_context *next_ctx; |
5a3126d4 | 2836 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2837 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2838 | int do_switch = 1; |
0793a61d | 2839 | |
108b02cf PZ |
2840 | if (likely(!ctx)) |
2841 | return; | |
10989fb2 | 2842 | |
108b02cf PZ |
2843 | cpuctx = __get_cpu_context(ctx); |
2844 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2845 | return; |
2846 | ||
c93f7669 | 2847 | rcu_read_lock(); |
8dc85d54 | 2848 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2849 | if (!next_ctx) |
2850 | goto unlock; | |
2851 | ||
2852 | parent = rcu_dereference(ctx->parent_ctx); | |
2853 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2854 | ||
2855 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2856 | if (!parent && !next_parent) |
5a3126d4 PZ |
2857 | goto unlock; |
2858 | ||
2859 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2860 | /* |
2861 | * Looks like the two contexts are clones, so we might be | |
2862 | * able to optimize the context switch. We lock both | |
2863 | * contexts and check that they are clones under the | |
2864 | * lock (including re-checking that neither has been | |
2865 | * uncloned in the meantime). It doesn't matter which | |
2866 | * order we take the locks because no other cpu could | |
2867 | * be trying to lock both of these tasks. | |
2868 | */ | |
e625cce1 TG |
2869 | raw_spin_lock(&ctx->lock); |
2870 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2871 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2872 | WRITE_ONCE(ctx->task, next); |
2873 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2874 | |
2875 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2876 | ||
63b6da39 PZ |
2877 | /* |
2878 | * RCU_INIT_POINTER here is safe because we've not | |
2879 | * modified the ctx and the above modification of | |
2880 | * ctx->task and ctx->task_ctx_data are immaterial | |
2881 | * since those values are always verified under | |
2882 | * ctx->lock which we're now holding. | |
2883 | */ | |
2884 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2885 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2886 | ||
c93f7669 | 2887 | do_switch = 0; |
bfbd3381 | 2888 | |
cdd6c482 | 2889 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2890 | } |
e625cce1 TG |
2891 | raw_spin_unlock(&next_ctx->lock); |
2892 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2893 | } |
5a3126d4 | 2894 | unlock: |
c93f7669 | 2895 | rcu_read_unlock(); |
564c2b21 | 2896 | |
c93f7669 | 2897 | if (do_switch) { |
facc4307 | 2898 | raw_spin_lock(&ctx->lock); |
8833d0e2 | 2899 | task_ctx_sched_out(cpuctx, ctx); |
facc4307 | 2900 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2901 | } |
0793a61d TG |
2902 | } |
2903 | ||
e48c1788 PZ |
2904 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2905 | ||
ba532500 YZ |
2906 | void perf_sched_cb_dec(struct pmu *pmu) |
2907 | { | |
e48c1788 PZ |
2908 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2909 | ||
ba532500 | 2910 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2911 | |
2912 | if (!--cpuctx->sched_cb_usage) | |
2913 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2914 | } |
2915 | ||
e48c1788 | 2916 | |
ba532500 YZ |
2917 | void perf_sched_cb_inc(struct pmu *pmu) |
2918 | { | |
e48c1788 PZ |
2919 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2920 | ||
2921 | if (!cpuctx->sched_cb_usage++) | |
2922 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2923 | ||
ba532500 YZ |
2924 | this_cpu_inc(perf_sched_cb_usages); |
2925 | } | |
2926 | ||
2927 | /* | |
2928 | * This function provides the context switch callback to the lower code | |
2929 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2930 | * |
2931 | * This callback is relevant even to per-cpu events; for example multi event | |
2932 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2933 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2934 | */ |
2935 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2936 | struct task_struct *next, | |
2937 | bool sched_in) | |
2938 | { | |
2939 | struct perf_cpu_context *cpuctx; | |
2940 | struct pmu *pmu; | |
ba532500 YZ |
2941 | |
2942 | if (prev == next) | |
2943 | return; | |
2944 | ||
e48c1788 PZ |
2945 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
2946 | pmu = cpuctx->unique_pmu; /* software PMUs will not have sched_task */ | |
ba532500 | 2947 | |
e48c1788 PZ |
2948 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2949 | continue; | |
ba532500 | 2950 | |
e48c1788 PZ |
2951 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
2952 | perf_pmu_disable(pmu); | |
ba532500 | 2953 | |
e48c1788 | 2954 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 2955 | |
e48c1788 PZ |
2956 | perf_pmu_enable(pmu); |
2957 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 2958 | } |
ba532500 YZ |
2959 | } |
2960 | ||
45ac1403 AH |
2961 | static void perf_event_switch(struct task_struct *task, |
2962 | struct task_struct *next_prev, bool sched_in); | |
2963 | ||
8dc85d54 PZ |
2964 | #define for_each_task_context_nr(ctxn) \ |
2965 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2966 | ||
2967 | /* | |
2968 | * Called from scheduler to remove the events of the current task, | |
2969 | * with interrupts disabled. | |
2970 | * | |
2971 | * We stop each event and update the event value in event->count. | |
2972 | * | |
2973 | * This does not protect us against NMI, but disable() | |
2974 | * sets the disabled bit in the control field of event _before_ | |
2975 | * accessing the event control register. If a NMI hits, then it will | |
2976 | * not restart the event. | |
2977 | */ | |
ab0cce56 JO |
2978 | void __perf_event_task_sched_out(struct task_struct *task, |
2979 | struct task_struct *next) | |
8dc85d54 PZ |
2980 | { |
2981 | int ctxn; | |
2982 | ||
ba532500 YZ |
2983 | if (__this_cpu_read(perf_sched_cb_usages)) |
2984 | perf_pmu_sched_task(task, next, false); | |
2985 | ||
45ac1403 AH |
2986 | if (atomic_read(&nr_switch_events)) |
2987 | perf_event_switch(task, next, false); | |
2988 | ||
8dc85d54 PZ |
2989 | for_each_task_context_nr(ctxn) |
2990 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2991 | |
2992 | /* | |
2993 | * if cgroup events exist on this CPU, then we need | |
2994 | * to check if we have to switch out PMU state. | |
2995 | * cgroup event are system-wide mode only | |
2996 | */ | |
4a32fea9 | 2997 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2998 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2999 | } |
3000 | ||
5b0311e1 FW |
3001 | /* |
3002 | * Called with IRQs disabled | |
3003 | */ | |
3004 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3005 | enum event_type_t event_type) | |
3006 | { | |
3007 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3008 | } |
3009 | ||
235c7fc7 | 3010 | static void |
5b0311e1 | 3011 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 3012 | struct perf_cpu_context *cpuctx) |
0793a61d | 3013 | { |
cdd6c482 | 3014 | struct perf_event *event; |
0793a61d | 3015 | |
889ff015 FW |
3016 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
3017 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3018 | continue; |
5632ab12 | 3019 | if (!event_filter_match(event)) |
3b6f9e5c PM |
3020 | continue; |
3021 | ||
e5d1367f SE |
3022 | /* may need to reset tstamp_enabled */ |
3023 | if (is_cgroup_event(event)) | |
3024 | perf_cgroup_mark_enabled(event, ctx); | |
3025 | ||
8c9ed8e1 | 3026 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 3027 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
3028 | |
3029 | /* | |
3030 | * If this pinned group hasn't been scheduled, | |
3031 | * put it in error state. | |
3032 | */ | |
cdd6c482 IM |
3033 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3034 | update_group_times(event); | |
3035 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 3036 | } |
3b6f9e5c | 3037 | } |
5b0311e1 FW |
3038 | } |
3039 | ||
3040 | static void | |
3041 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 3042 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
3043 | { |
3044 | struct perf_event *event; | |
3045 | int can_add_hw = 1; | |
3b6f9e5c | 3046 | |
889ff015 FW |
3047 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
3048 | /* Ignore events in OFF or ERROR state */ | |
3049 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3050 | continue; |
04289bb9 IM |
3051 | /* |
3052 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 3053 | * of events: |
04289bb9 | 3054 | */ |
5632ab12 | 3055 | if (!event_filter_match(event)) |
0793a61d TG |
3056 | continue; |
3057 | ||
e5d1367f SE |
3058 | /* may need to reset tstamp_enabled */ |
3059 | if (is_cgroup_event(event)) | |
3060 | perf_cgroup_mark_enabled(event, ctx); | |
3061 | ||
9ed6060d | 3062 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3063 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3064 | can_add_hw = 0; |
9ed6060d | 3065 | } |
0793a61d | 3066 | } |
5b0311e1 FW |
3067 | } |
3068 | ||
3069 | static void | |
3070 | ctx_sched_in(struct perf_event_context *ctx, | |
3071 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3072 | enum event_type_t event_type, |
3073 | struct task_struct *task) | |
5b0311e1 | 3074 | { |
db24d33e | 3075 | int is_active = ctx->is_active; |
c994d613 PZ |
3076 | u64 now; |
3077 | ||
3078 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3079 | |
5b0311e1 | 3080 | if (likely(!ctx->nr_events)) |
facc4307 | 3081 | return; |
5b0311e1 | 3082 | |
3cbaa590 | 3083 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3084 | if (ctx->task) { |
3085 | if (!is_active) | |
3086 | cpuctx->task_ctx = ctx; | |
3087 | else | |
3088 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3089 | } | |
3090 | ||
3cbaa590 PZ |
3091 | is_active ^= ctx->is_active; /* changed bits */ |
3092 | ||
3093 | if (is_active & EVENT_TIME) { | |
3094 | /* start ctx time */ | |
3095 | now = perf_clock(); | |
3096 | ctx->timestamp = now; | |
3097 | perf_cgroup_set_timestamp(task, ctx); | |
3098 | } | |
3099 | ||
5b0311e1 FW |
3100 | /* |
3101 | * First go through the list and put on any pinned groups | |
3102 | * in order to give them the best chance of going on. | |
3103 | */ | |
3cbaa590 | 3104 | if (is_active & EVENT_PINNED) |
6e37738a | 3105 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3106 | |
3107 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3108 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3109 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3110 | } |
3111 | ||
329c0e01 | 3112 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3113 | enum event_type_t event_type, |
3114 | struct task_struct *task) | |
329c0e01 FW |
3115 | { |
3116 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3117 | ||
e5d1367f | 3118 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3119 | } |
3120 | ||
e5d1367f SE |
3121 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3122 | struct task_struct *task) | |
235c7fc7 | 3123 | { |
108b02cf | 3124 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3125 | |
108b02cf | 3126 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3127 | if (cpuctx->task_ctx == ctx) |
3128 | return; | |
3129 | ||
facc4307 | 3130 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3131 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3132 | /* |
3133 | * We want to keep the following priority order: | |
3134 | * cpu pinned (that don't need to move), task pinned, | |
3135 | * cpu flexible, task flexible. | |
3136 | */ | |
3137 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3138 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3139 | perf_pmu_enable(ctx->pmu); |
3140 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3141 | } |
3142 | ||
8dc85d54 PZ |
3143 | /* |
3144 | * Called from scheduler to add the events of the current task | |
3145 | * with interrupts disabled. | |
3146 | * | |
3147 | * We restore the event value and then enable it. | |
3148 | * | |
3149 | * This does not protect us against NMI, but enable() | |
3150 | * sets the enabled bit in the control field of event _before_ | |
3151 | * accessing the event control register. If a NMI hits, then it will | |
3152 | * keep the event running. | |
3153 | */ | |
ab0cce56 JO |
3154 | void __perf_event_task_sched_in(struct task_struct *prev, |
3155 | struct task_struct *task) | |
8dc85d54 PZ |
3156 | { |
3157 | struct perf_event_context *ctx; | |
3158 | int ctxn; | |
3159 | ||
7e41d177 PZ |
3160 | /* |
3161 | * If cgroup events exist on this CPU, then we need to check if we have | |
3162 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3163 | * | |
3164 | * Since cgroup events are CPU events, we must schedule these in before | |
3165 | * we schedule in the task events. | |
3166 | */ | |
3167 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3168 | perf_cgroup_sched_in(prev, task); | |
3169 | ||
8dc85d54 PZ |
3170 | for_each_task_context_nr(ctxn) { |
3171 | ctx = task->perf_event_ctxp[ctxn]; | |
3172 | if (likely(!ctx)) | |
3173 | continue; | |
3174 | ||
e5d1367f | 3175 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3176 | } |
d010b332 | 3177 | |
45ac1403 AH |
3178 | if (atomic_read(&nr_switch_events)) |
3179 | perf_event_switch(task, prev, true); | |
3180 | ||
ba532500 YZ |
3181 | if (__this_cpu_read(perf_sched_cb_usages)) |
3182 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3183 | } |
3184 | ||
abd50713 PZ |
3185 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3186 | { | |
3187 | u64 frequency = event->attr.sample_freq; | |
3188 | u64 sec = NSEC_PER_SEC; | |
3189 | u64 divisor, dividend; | |
3190 | ||
3191 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3192 | ||
3193 | count_fls = fls64(count); | |
3194 | nsec_fls = fls64(nsec); | |
3195 | frequency_fls = fls64(frequency); | |
3196 | sec_fls = 30; | |
3197 | ||
3198 | /* | |
3199 | * We got @count in @nsec, with a target of sample_freq HZ | |
3200 | * the target period becomes: | |
3201 | * | |
3202 | * @count * 10^9 | |
3203 | * period = ------------------- | |
3204 | * @nsec * sample_freq | |
3205 | * | |
3206 | */ | |
3207 | ||
3208 | /* | |
3209 | * Reduce accuracy by one bit such that @a and @b converge | |
3210 | * to a similar magnitude. | |
3211 | */ | |
fe4b04fa | 3212 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3213 | do { \ |
3214 | if (a##_fls > b##_fls) { \ | |
3215 | a >>= 1; \ | |
3216 | a##_fls--; \ | |
3217 | } else { \ | |
3218 | b >>= 1; \ | |
3219 | b##_fls--; \ | |
3220 | } \ | |
3221 | } while (0) | |
3222 | ||
3223 | /* | |
3224 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3225 | * the other, so that finally we can do a u64/u64 division. | |
3226 | */ | |
3227 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3228 | REDUCE_FLS(nsec, frequency); | |
3229 | REDUCE_FLS(sec, count); | |
3230 | } | |
3231 | ||
3232 | if (count_fls + sec_fls > 64) { | |
3233 | divisor = nsec * frequency; | |
3234 | ||
3235 | while (count_fls + sec_fls > 64) { | |
3236 | REDUCE_FLS(count, sec); | |
3237 | divisor >>= 1; | |
3238 | } | |
3239 | ||
3240 | dividend = count * sec; | |
3241 | } else { | |
3242 | dividend = count * sec; | |
3243 | ||
3244 | while (nsec_fls + frequency_fls > 64) { | |
3245 | REDUCE_FLS(nsec, frequency); | |
3246 | dividend >>= 1; | |
3247 | } | |
3248 | ||
3249 | divisor = nsec * frequency; | |
3250 | } | |
3251 | ||
f6ab91ad PZ |
3252 | if (!divisor) |
3253 | return dividend; | |
3254 | ||
abd50713 PZ |
3255 | return div64_u64(dividend, divisor); |
3256 | } | |
3257 | ||
e050e3f0 SE |
3258 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3259 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3260 | ||
f39d47ff | 3261 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3262 | { |
cdd6c482 | 3263 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3264 | s64 period, sample_period; |
bd2b5b12 PZ |
3265 | s64 delta; |
3266 | ||
abd50713 | 3267 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3268 | |
3269 | delta = (s64)(period - hwc->sample_period); | |
3270 | delta = (delta + 7) / 8; /* low pass filter */ | |
3271 | ||
3272 | sample_period = hwc->sample_period + delta; | |
3273 | ||
3274 | if (!sample_period) | |
3275 | sample_period = 1; | |
3276 | ||
bd2b5b12 | 3277 | hwc->sample_period = sample_period; |
abd50713 | 3278 | |
e7850595 | 3279 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3280 | if (disable) |
3281 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3282 | ||
e7850595 | 3283 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3284 | |
3285 | if (disable) | |
3286 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3287 | } |
bd2b5b12 PZ |
3288 | } |
3289 | ||
e050e3f0 SE |
3290 | /* |
3291 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3292 | * events. At the same time, make sure, having freq events does not change | |
3293 | * the rate of unthrottling as that would introduce bias. | |
3294 | */ | |
3295 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3296 | int needs_unthr) | |
60db5e09 | 3297 | { |
cdd6c482 IM |
3298 | struct perf_event *event; |
3299 | struct hw_perf_event *hwc; | |
e050e3f0 | 3300 | u64 now, period = TICK_NSEC; |
abd50713 | 3301 | s64 delta; |
60db5e09 | 3302 | |
e050e3f0 SE |
3303 | /* |
3304 | * only need to iterate over all events iff: | |
3305 | * - context have events in frequency mode (needs freq adjust) | |
3306 | * - there are events to unthrottle on this cpu | |
3307 | */ | |
3308 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3309 | return; |
3310 | ||
e050e3f0 | 3311 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3312 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3313 | |
03541f8b | 3314 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3315 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3316 | continue; |
3317 | ||
5632ab12 | 3318 | if (!event_filter_match(event)) |
5d27c23d PZ |
3319 | continue; |
3320 | ||
44377277 AS |
3321 | perf_pmu_disable(event->pmu); |
3322 | ||
cdd6c482 | 3323 | hwc = &event->hw; |
6a24ed6c | 3324 | |
ae23bff1 | 3325 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3326 | hwc->interrupts = 0; |
cdd6c482 | 3327 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3328 | event->pmu->start(event, 0); |
a78ac325 PZ |
3329 | } |
3330 | ||
cdd6c482 | 3331 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3332 | goto next; |
60db5e09 | 3333 | |
e050e3f0 SE |
3334 | /* |
3335 | * stop the event and update event->count | |
3336 | */ | |
3337 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3338 | ||
e7850595 | 3339 | now = local64_read(&event->count); |
abd50713 PZ |
3340 | delta = now - hwc->freq_count_stamp; |
3341 | hwc->freq_count_stamp = now; | |
60db5e09 | 3342 | |
e050e3f0 SE |
3343 | /* |
3344 | * restart the event | |
3345 | * reload only if value has changed | |
f39d47ff SE |
3346 | * we have stopped the event so tell that |
3347 | * to perf_adjust_period() to avoid stopping it | |
3348 | * twice. | |
e050e3f0 | 3349 | */ |
abd50713 | 3350 | if (delta > 0) |
f39d47ff | 3351 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3352 | |
3353 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3354 | next: |
3355 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3356 | } |
e050e3f0 | 3357 | |
f39d47ff | 3358 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3359 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3360 | } |
3361 | ||
235c7fc7 | 3362 | /* |
cdd6c482 | 3363 | * Round-robin a context's events: |
235c7fc7 | 3364 | */ |
cdd6c482 | 3365 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3366 | { |
dddd3379 TG |
3367 | /* |
3368 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3369 | * disabled by the inheritance code. | |
3370 | */ | |
3371 | if (!ctx->rotate_disable) | |
3372 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3373 | } |
3374 | ||
9e630205 | 3375 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3376 | { |
8dc85d54 | 3377 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3378 | int rotate = 0; |
7fc23a53 | 3379 | |
b5ab4cd5 | 3380 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3381 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3382 | rotate = 1; | |
3383 | } | |
235c7fc7 | 3384 | |
8dc85d54 | 3385 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3386 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3387 | if (ctx->nr_events != ctx->nr_active) |
3388 | rotate = 1; | |
3389 | } | |
9717e6cd | 3390 | |
e050e3f0 | 3391 | if (!rotate) |
0f5a2601 PZ |
3392 | goto done; |
3393 | ||
facc4307 | 3394 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3395 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3396 | |
e050e3f0 SE |
3397 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3398 | if (ctx) | |
3399 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3400 | |
e050e3f0 SE |
3401 | rotate_ctx(&cpuctx->ctx); |
3402 | if (ctx) | |
3403 | rotate_ctx(ctx); | |
235c7fc7 | 3404 | |
e050e3f0 | 3405 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3406 | |
0f5a2601 PZ |
3407 | perf_pmu_enable(cpuctx->ctx.pmu); |
3408 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3409 | done: |
9e630205 SE |
3410 | |
3411 | return rotate; | |
e9d2b064 PZ |
3412 | } |
3413 | ||
3414 | void perf_event_task_tick(void) | |
3415 | { | |
2fde4f94 MR |
3416 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3417 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3418 | int throttled; |
b5ab4cd5 | 3419 | |
e9d2b064 PZ |
3420 | WARN_ON(!irqs_disabled()); |
3421 | ||
e050e3f0 SE |
3422 | __this_cpu_inc(perf_throttled_seq); |
3423 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3424 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3425 | |
2fde4f94 | 3426 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3427 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3428 | } |
3429 | ||
889ff015 FW |
3430 | static int event_enable_on_exec(struct perf_event *event, |
3431 | struct perf_event_context *ctx) | |
3432 | { | |
3433 | if (!event->attr.enable_on_exec) | |
3434 | return 0; | |
3435 | ||
3436 | event->attr.enable_on_exec = 0; | |
3437 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3438 | return 0; | |
3439 | ||
1d9b482e | 3440 | __perf_event_mark_enabled(event); |
889ff015 FW |
3441 | |
3442 | return 1; | |
3443 | } | |
3444 | ||
57e7986e | 3445 | /* |
cdd6c482 | 3446 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3447 | * This expects task == current. |
3448 | */ | |
c1274499 | 3449 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3450 | { |
c1274499 | 3451 | struct perf_event_context *ctx, *clone_ctx = NULL; |
3e349507 | 3452 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3453 | struct perf_event *event; |
57e7986e PM |
3454 | unsigned long flags; |
3455 | int enabled = 0; | |
3456 | ||
3457 | local_irq_save(flags); | |
c1274499 | 3458 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3459 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3460 | goto out; |
3461 | ||
3e349507 PZ |
3462 | cpuctx = __get_cpu_context(ctx); |
3463 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3464 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
3e349507 PZ |
3465 | list_for_each_entry(event, &ctx->event_list, event_entry) |
3466 | enabled |= event_enable_on_exec(event, ctx); | |
57e7986e PM |
3467 | |
3468 | /* | |
3e349507 | 3469 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3470 | */ |
3e349507 | 3471 | if (enabled) { |
211de6eb | 3472 | clone_ctx = unclone_ctx(ctx); |
3e349507 PZ |
3473 | ctx_resched(cpuctx, ctx); |
3474 | } | |
3475 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3476 | |
9ed6060d | 3477 | out: |
57e7986e | 3478 | local_irq_restore(flags); |
211de6eb PZ |
3479 | |
3480 | if (clone_ctx) | |
3481 | put_ctx(clone_ctx); | |
57e7986e PM |
3482 | } |
3483 | ||
0492d4c5 PZ |
3484 | struct perf_read_data { |
3485 | struct perf_event *event; | |
3486 | bool group; | |
7d88962e | 3487 | int ret; |
0492d4c5 PZ |
3488 | }; |
3489 | ||
d6a2f903 DCC |
3490 | static int find_cpu_to_read(struct perf_event *event, int local_cpu) |
3491 | { | |
3492 | int event_cpu = event->oncpu; | |
3493 | u16 local_pkg, event_pkg; | |
3494 | ||
3495 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
3496 | event_pkg = topology_physical_package_id(event_cpu); | |
3497 | local_pkg = topology_physical_package_id(local_cpu); | |
3498 | ||
3499 | if (event_pkg == local_pkg) | |
3500 | return local_cpu; | |
3501 | } | |
3502 | ||
3503 | return event_cpu; | |
3504 | } | |
3505 | ||
0793a61d | 3506 | /* |
cdd6c482 | 3507 | * Cross CPU call to read the hardware event |
0793a61d | 3508 | */ |
cdd6c482 | 3509 | static void __perf_event_read(void *info) |
0793a61d | 3510 | { |
0492d4c5 PZ |
3511 | struct perf_read_data *data = info; |
3512 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3513 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3514 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3515 | struct pmu *pmu = event->pmu; |
621a01ea | 3516 | |
e1ac3614 PM |
3517 | /* |
3518 | * If this is a task context, we need to check whether it is | |
3519 | * the current task context of this cpu. If not it has been | |
3520 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3521 | * event->count would have been updated to a recent sample |
3522 | * when the event was scheduled out. | |
e1ac3614 PM |
3523 | */ |
3524 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3525 | return; | |
3526 | ||
e625cce1 | 3527 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3528 | if (ctx->is_active) { |
542e72fc | 3529 | update_context_time(ctx); |
e5d1367f SE |
3530 | update_cgrp_time_from_event(event); |
3531 | } | |
0492d4c5 | 3532 | |
cdd6c482 | 3533 | update_event_times(event); |
4a00c16e SB |
3534 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3535 | goto unlock; | |
0492d4c5 | 3536 | |
4a00c16e SB |
3537 | if (!data->group) { |
3538 | pmu->read(event); | |
3539 | data->ret = 0; | |
0492d4c5 | 3540 | goto unlock; |
4a00c16e SB |
3541 | } |
3542 | ||
3543 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3544 | ||
3545 | pmu->read(event); | |
0492d4c5 PZ |
3546 | |
3547 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3548 | update_event_times(sub); | |
4a00c16e SB |
3549 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3550 | /* | |
3551 | * Use sibling's PMU rather than @event's since | |
3552 | * sibling could be on different (eg: software) PMU. | |
3553 | */ | |
0492d4c5 | 3554 | sub->pmu->read(sub); |
4a00c16e | 3555 | } |
0492d4c5 | 3556 | } |
4a00c16e SB |
3557 | |
3558 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3559 | |
3560 | unlock: | |
e625cce1 | 3561 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3562 | } |
3563 | ||
b5e58793 PZ |
3564 | static inline u64 perf_event_count(struct perf_event *event) |
3565 | { | |
eacd3ecc MF |
3566 | if (event->pmu->count) |
3567 | return event->pmu->count(event); | |
3568 | ||
3569 | return __perf_event_count(event); | |
b5e58793 PZ |
3570 | } |
3571 | ||
ffe8690c KX |
3572 | /* |
3573 | * NMI-safe method to read a local event, that is an event that | |
3574 | * is: | |
3575 | * - either for the current task, or for this CPU | |
3576 | * - does not have inherit set, for inherited task events | |
3577 | * will not be local and we cannot read them atomically | |
3578 | * - must not have a pmu::count method | |
3579 | */ | |
3580 | u64 perf_event_read_local(struct perf_event *event) | |
3581 | { | |
3582 | unsigned long flags; | |
3583 | u64 val; | |
3584 | ||
3585 | /* | |
3586 | * Disabling interrupts avoids all counter scheduling (context | |
3587 | * switches, timer based rotation and IPIs). | |
3588 | */ | |
3589 | local_irq_save(flags); | |
3590 | ||
3591 | /* If this is a per-task event, it must be for current */ | |
3592 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3593 | event->hw.target != current); | |
3594 | ||
3595 | /* If this is a per-CPU event, it must be for this CPU */ | |
3596 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3597 | event->cpu != smp_processor_id()); | |
3598 | ||
3599 | /* | |
3600 | * It must not be an event with inherit set, we cannot read | |
3601 | * all child counters from atomic context. | |
3602 | */ | |
3603 | WARN_ON_ONCE(event->attr.inherit); | |
3604 | ||
3605 | /* | |
3606 | * It must not have a pmu::count method, those are not | |
3607 | * NMI safe. | |
3608 | */ | |
3609 | WARN_ON_ONCE(event->pmu->count); | |
3610 | ||
3611 | /* | |
3612 | * If the event is currently on this CPU, its either a per-task event, | |
3613 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3614 | * oncpu == -1). | |
3615 | */ | |
3616 | if (event->oncpu == smp_processor_id()) | |
3617 | event->pmu->read(event); | |
3618 | ||
3619 | val = local64_read(&event->count); | |
3620 | local_irq_restore(flags); | |
3621 | ||
3622 | return val; | |
3623 | } | |
3624 | ||
7d88962e | 3625 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3626 | { |
d6a2f903 | 3627 | int ret = 0, cpu_to_read, local_cpu; |
7d88962e | 3628 | |
0793a61d | 3629 | /* |
cdd6c482 IM |
3630 | * If event is enabled and currently active on a CPU, update the |
3631 | * value in the event structure: | |
0793a61d | 3632 | */ |
cdd6c482 | 3633 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3634 | struct perf_read_data data = { |
3635 | .event = event, | |
3636 | .group = group, | |
7d88962e | 3637 | .ret = 0, |
0492d4c5 | 3638 | }; |
d6a2f903 DCC |
3639 | |
3640 | local_cpu = get_cpu(); | |
3641 | cpu_to_read = find_cpu_to_read(event, local_cpu); | |
3642 | put_cpu(); | |
3643 | ||
58763148 PZ |
3644 | /* |
3645 | * Purposely ignore the smp_call_function_single() return | |
3646 | * value. | |
3647 | * | |
3648 | * If event->oncpu isn't a valid CPU it means the event got | |
3649 | * scheduled out and that will have updated the event count. | |
3650 | * | |
3651 | * Therefore, either way, we'll have an up-to-date event count | |
3652 | * after this. | |
3653 | */ | |
2cc53841 | 3654 | (void)smp_call_function_single(cpu_to_read, __perf_event_read, &data, 1); |
58763148 | 3655 | ret = data.ret; |
cdd6c482 | 3656 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3657 | struct perf_event_context *ctx = event->ctx; |
3658 | unsigned long flags; | |
3659 | ||
e625cce1 | 3660 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3661 | /* |
3662 | * may read while context is not active | |
3663 | * (e.g., thread is blocked), in that case | |
3664 | * we cannot update context time | |
3665 | */ | |
e5d1367f | 3666 | if (ctx->is_active) { |
c530ccd9 | 3667 | update_context_time(ctx); |
e5d1367f SE |
3668 | update_cgrp_time_from_event(event); |
3669 | } | |
0492d4c5 PZ |
3670 | if (group) |
3671 | update_group_times(event); | |
3672 | else | |
3673 | update_event_times(event); | |
e625cce1 | 3674 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3675 | } |
7d88962e SB |
3676 | |
3677 | return ret; | |
0793a61d TG |
3678 | } |
3679 | ||
a63eaf34 | 3680 | /* |
cdd6c482 | 3681 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3682 | */ |
eb184479 | 3683 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3684 | { |
e625cce1 | 3685 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3686 | mutex_init(&ctx->mutex); |
2fde4f94 | 3687 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3688 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3689 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3690 | INIT_LIST_HEAD(&ctx->event_list); |
3691 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3692 | } |
3693 | ||
3694 | static struct perf_event_context * | |
3695 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3696 | { | |
3697 | struct perf_event_context *ctx; | |
3698 | ||
3699 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3700 | if (!ctx) | |
3701 | return NULL; | |
3702 | ||
3703 | __perf_event_init_context(ctx); | |
3704 | if (task) { | |
3705 | ctx->task = task; | |
3706 | get_task_struct(task); | |
0793a61d | 3707 | } |
eb184479 PZ |
3708 | ctx->pmu = pmu; |
3709 | ||
3710 | return ctx; | |
a63eaf34 PM |
3711 | } |
3712 | ||
2ebd4ffb MH |
3713 | static struct task_struct * |
3714 | find_lively_task_by_vpid(pid_t vpid) | |
3715 | { | |
3716 | struct task_struct *task; | |
0793a61d TG |
3717 | |
3718 | rcu_read_lock(); | |
2ebd4ffb | 3719 | if (!vpid) |
0793a61d TG |
3720 | task = current; |
3721 | else | |
2ebd4ffb | 3722 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3723 | if (task) |
3724 | get_task_struct(task); | |
3725 | rcu_read_unlock(); | |
3726 | ||
3727 | if (!task) | |
3728 | return ERR_PTR(-ESRCH); | |
3729 | ||
2ebd4ffb | 3730 | return task; |
2ebd4ffb MH |
3731 | } |
3732 | ||
fe4b04fa PZ |
3733 | /* |
3734 | * Returns a matching context with refcount and pincount. | |
3735 | */ | |
108b02cf | 3736 | static struct perf_event_context * |
4af57ef2 YZ |
3737 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3738 | struct perf_event *event) | |
0793a61d | 3739 | { |
211de6eb | 3740 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3741 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3742 | void *task_ctx_data = NULL; |
25346b93 | 3743 | unsigned long flags; |
8dc85d54 | 3744 | int ctxn, err; |
4af57ef2 | 3745 | int cpu = event->cpu; |
0793a61d | 3746 | |
22a4ec72 | 3747 | if (!task) { |
cdd6c482 | 3748 | /* Must be root to operate on a CPU event: */ |
0764771d | 3749 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3750 | return ERR_PTR(-EACCES); |
3751 | ||
0793a61d | 3752 | /* |
cdd6c482 | 3753 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3754 | * offline CPU and activate it when the CPU comes up, but |
3755 | * that's for later. | |
3756 | */ | |
f6325e30 | 3757 | if (!cpu_online(cpu)) |
0793a61d TG |
3758 | return ERR_PTR(-ENODEV); |
3759 | ||
108b02cf | 3760 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3761 | ctx = &cpuctx->ctx; |
c93f7669 | 3762 | get_ctx(ctx); |
fe4b04fa | 3763 | ++ctx->pin_count; |
0793a61d | 3764 | |
0793a61d TG |
3765 | return ctx; |
3766 | } | |
3767 | ||
8dc85d54 PZ |
3768 | err = -EINVAL; |
3769 | ctxn = pmu->task_ctx_nr; | |
3770 | if (ctxn < 0) | |
3771 | goto errout; | |
3772 | ||
4af57ef2 YZ |
3773 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3774 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3775 | if (!task_ctx_data) { | |
3776 | err = -ENOMEM; | |
3777 | goto errout; | |
3778 | } | |
3779 | } | |
3780 | ||
9ed6060d | 3781 | retry: |
8dc85d54 | 3782 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3783 | if (ctx) { |
211de6eb | 3784 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3785 | ++ctx->pin_count; |
4af57ef2 YZ |
3786 | |
3787 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3788 | ctx->task_ctx_data = task_ctx_data; | |
3789 | task_ctx_data = NULL; | |
3790 | } | |
e625cce1 | 3791 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3792 | |
3793 | if (clone_ctx) | |
3794 | put_ctx(clone_ctx); | |
9137fb28 | 3795 | } else { |
eb184479 | 3796 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3797 | err = -ENOMEM; |
3798 | if (!ctx) | |
3799 | goto errout; | |
eb184479 | 3800 | |
4af57ef2 YZ |
3801 | if (task_ctx_data) { |
3802 | ctx->task_ctx_data = task_ctx_data; | |
3803 | task_ctx_data = NULL; | |
3804 | } | |
3805 | ||
dbe08d82 ON |
3806 | err = 0; |
3807 | mutex_lock(&task->perf_event_mutex); | |
3808 | /* | |
3809 | * If it has already passed perf_event_exit_task(). | |
3810 | * we must see PF_EXITING, it takes this mutex too. | |
3811 | */ | |
3812 | if (task->flags & PF_EXITING) | |
3813 | err = -ESRCH; | |
3814 | else if (task->perf_event_ctxp[ctxn]) | |
3815 | err = -EAGAIN; | |
fe4b04fa | 3816 | else { |
9137fb28 | 3817 | get_ctx(ctx); |
fe4b04fa | 3818 | ++ctx->pin_count; |
dbe08d82 | 3819 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3820 | } |
dbe08d82 ON |
3821 | mutex_unlock(&task->perf_event_mutex); |
3822 | ||
3823 | if (unlikely(err)) { | |
9137fb28 | 3824 | put_ctx(ctx); |
dbe08d82 ON |
3825 | |
3826 | if (err == -EAGAIN) | |
3827 | goto retry; | |
3828 | goto errout; | |
a63eaf34 PM |
3829 | } |
3830 | } | |
3831 | ||
4af57ef2 | 3832 | kfree(task_ctx_data); |
0793a61d | 3833 | return ctx; |
c93f7669 | 3834 | |
9ed6060d | 3835 | errout: |
4af57ef2 | 3836 | kfree(task_ctx_data); |
c93f7669 | 3837 | return ERR_PTR(err); |
0793a61d TG |
3838 | } |
3839 | ||
6fb2915d | 3840 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3841 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3842 | |
cdd6c482 | 3843 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3844 | { |
cdd6c482 | 3845 | struct perf_event *event; |
592903cd | 3846 | |
cdd6c482 IM |
3847 | event = container_of(head, struct perf_event, rcu_head); |
3848 | if (event->ns) | |
3849 | put_pid_ns(event->ns); | |
6fb2915d | 3850 | perf_event_free_filter(event); |
cdd6c482 | 3851 | kfree(event); |
592903cd PZ |
3852 | } |
3853 | ||
b69cf536 PZ |
3854 | static void ring_buffer_attach(struct perf_event *event, |
3855 | struct ring_buffer *rb); | |
925d519a | 3856 | |
f2fb6bef KL |
3857 | static void detach_sb_event(struct perf_event *event) |
3858 | { | |
3859 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3860 | ||
3861 | raw_spin_lock(&pel->lock); | |
3862 | list_del_rcu(&event->sb_list); | |
3863 | raw_spin_unlock(&pel->lock); | |
3864 | } | |
3865 | ||
a4f144eb | 3866 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3867 | { |
a4f144eb DCC |
3868 | struct perf_event_attr *attr = &event->attr; |
3869 | ||
f2fb6bef | 3870 | if (event->parent) |
a4f144eb | 3871 | return false; |
f2fb6bef KL |
3872 | |
3873 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3874 | return false; |
f2fb6bef | 3875 | |
a4f144eb DCC |
3876 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3877 | attr->comm || attr->comm_exec || | |
3878 | attr->task || | |
3879 | attr->context_switch) | |
3880 | return true; | |
3881 | return false; | |
3882 | } | |
3883 | ||
3884 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3885 | { | |
3886 | if (is_sb_event(event)) | |
3887 | detach_sb_event(event); | |
f2fb6bef KL |
3888 | } |
3889 | ||
4beb31f3 | 3890 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3891 | { |
4beb31f3 FW |
3892 | if (event->parent) |
3893 | return; | |
3894 | ||
4beb31f3 FW |
3895 | if (is_cgroup_event(event)) |
3896 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3897 | } | |
925d519a | 3898 | |
555e0c1e FW |
3899 | #ifdef CONFIG_NO_HZ_FULL |
3900 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3901 | #endif | |
3902 | ||
3903 | static void unaccount_freq_event_nohz(void) | |
3904 | { | |
3905 | #ifdef CONFIG_NO_HZ_FULL | |
3906 | spin_lock(&nr_freq_lock); | |
3907 | if (atomic_dec_and_test(&nr_freq_events)) | |
3908 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3909 | spin_unlock(&nr_freq_lock); | |
3910 | #endif | |
3911 | } | |
3912 | ||
3913 | static void unaccount_freq_event(void) | |
3914 | { | |
3915 | if (tick_nohz_full_enabled()) | |
3916 | unaccount_freq_event_nohz(); | |
3917 | else | |
3918 | atomic_dec(&nr_freq_events); | |
3919 | } | |
3920 | ||
4beb31f3 FW |
3921 | static void unaccount_event(struct perf_event *event) |
3922 | { | |
25432ae9 PZ |
3923 | bool dec = false; |
3924 | ||
4beb31f3 FW |
3925 | if (event->parent) |
3926 | return; | |
3927 | ||
3928 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3929 | dec = true; |
4beb31f3 FW |
3930 | if (event->attr.mmap || event->attr.mmap_data) |
3931 | atomic_dec(&nr_mmap_events); | |
3932 | if (event->attr.comm) | |
3933 | atomic_dec(&nr_comm_events); | |
3934 | if (event->attr.task) | |
3935 | atomic_dec(&nr_task_events); | |
948b26b6 | 3936 | if (event->attr.freq) |
555e0c1e | 3937 | unaccount_freq_event(); |
45ac1403 | 3938 | if (event->attr.context_switch) { |
25432ae9 | 3939 | dec = true; |
45ac1403 AH |
3940 | atomic_dec(&nr_switch_events); |
3941 | } | |
4beb31f3 | 3942 | if (is_cgroup_event(event)) |
25432ae9 | 3943 | dec = true; |
4beb31f3 | 3944 | if (has_branch_stack(event)) |
25432ae9 PZ |
3945 | dec = true; |
3946 | ||
9107c89e PZ |
3947 | if (dec) { |
3948 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
3949 | schedule_delayed_work(&perf_sched_work, HZ); | |
3950 | } | |
4beb31f3 FW |
3951 | |
3952 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
3953 | |
3954 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 3955 | } |
925d519a | 3956 | |
9107c89e PZ |
3957 | static void perf_sched_delayed(struct work_struct *work) |
3958 | { | |
3959 | mutex_lock(&perf_sched_mutex); | |
3960 | if (atomic_dec_and_test(&perf_sched_count)) | |
3961 | static_branch_disable(&perf_sched_events); | |
3962 | mutex_unlock(&perf_sched_mutex); | |
3963 | } | |
3964 | ||
bed5b25a AS |
3965 | /* |
3966 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3967 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3968 | * at a time, so we disallow creating events that might conflict, namely: | |
3969 | * | |
3970 | * 1) cpu-wide events in the presence of per-task events, | |
3971 | * 2) per-task events in the presence of cpu-wide events, | |
3972 | * 3) two matching events on the same context. | |
3973 | * | |
3974 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 3975 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
3976 | */ |
3977 | static int exclusive_event_init(struct perf_event *event) | |
3978 | { | |
3979 | struct pmu *pmu = event->pmu; | |
3980 | ||
3981 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3982 | return 0; | |
3983 | ||
3984 | /* | |
3985 | * Prevent co-existence of per-task and cpu-wide events on the | |
3986 | * same exclusive pmu. | |
3987 | * | |
3988 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3989 | * events on this "exclusive" pmu, positive means there are | |
3990 | * per-task events. | |
3991 | * | |
3992 | * Since this is called in perf_event_alloc() path, event::ctx | |
3993 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3994 | * to mean "per-task event", because unlike other attach states it | |
3995 | * never gets cleared. | |
3996 | */ | |
3997 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3998 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3999 | return -EBUSY; | |
4000 | } else { | |
4001 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4002 | return -EBUSY; | |
4003 | } | |
4004 | ||
4005 | return 0; | |
4006 | } | |
4007 | ||
4008 | static void exclusive_event_destroy(struct perf_event *event) | |
4009 | { | |
4010 | struct pmu *pmu = event->pmu; | |
4011 | ||
4012 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4013 | return; | |
4014 | ||
4015 | /* see comment in exclusive_event_init() */ | |
4016 | if (event->attach_state & PERF_ATTACH_TASK) | |
4017 | atomic_dec(&pmu->exclusive_cnt); | |
4018 | else | |
4019 | atomic_inc(&pmu->exclusive_cnt); | |
4020 | } | |
4021 | ||
4022 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4023 | { | |
3bf6215a | 4024 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4025 | (e1->cpu == e2->cpu || |
4026 | e1->cpu == -1 || | |
4027 | e2->cpu == -1)) | |
4028 | return true; | |
4029 | return false; | |
4030 | } | |
4031 | ||
4032 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4033 | static bool exclusive_event_installable(struct perf_event *event, | |
4034 | struct perf_event_context *ctx) | |
4035 | { | |
4036 | struct perf_event *iter_event; | |
4037 | struct pmu *pmu = event->pmu; | |
4038 | ||
4039 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4040 | return true; | |
4041 | ||
4042 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4043 | if (exclusive_event_match(iter_event, event)) | |
4044 | return false; | |
4045 | } | |
4046 | ||
4047 | return true; | |
4048 | } | |
4049 | ||
375637bc AS |
4050 | static void perf_addr_filters_splice(struct perf_event *event, |
4051 | struct list_head *head); | |
4052 | ||
683ede43 | 4053 | static void _free_event(struct perf_event *event) |
f1600952 | 4054 | { |
e360adbe | 4055 | irq_work_sync(&event->pending); |
925d519a | 4056 | |
4beb31f3 | 4057 | unaccount_event(event); |
9ee318a7 | 4058 | |
76369139 | 4059 | if (event->rb) { |
9bb5d40c PZ |
4060 | /* |
4061 | * Can happen when we close an event with re-directed output. | |
4062 | * | |
4063 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4064 | * over us; possibly making our ring_buffer_put() the last. | |
4065 | */ | |
4066 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4067 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4068 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4069 | } |
4070 | ||
e5d1367f SE |
4071 | if (is_cgroup_event(event)) |
4072 | perf_detach_cgroup(event); | |
4073 | ||
a0733e69 PZ |
4074 | if (!event->parent) { |
4075 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4076 | put_callchain_buffers(); | |
4077 | } | |
4078 | ||
4079 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4080 | perf_addr_filters_splice(event, NULL); |
4081 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4082 | |
4083 | if (event->destroy) | |
4084 | event->destroy(event); | |
4085 | ||
4086 | if (event->ctx) | |
4087 | put_ctx(event->ctx); | |
4088 | ||
62a92c8f AS |
4089 | exclusive_event_destroy(event); |
4090 | module_put(event->pmu->module); | |
a0733e69 PZ |
4091 | |
4092 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4093 | } |
4094 | ||
683ede43 PZ |
4095 | /* |
4096 | * Used to free events which have a known refcount of 1, such as in error paths | |
4097 | * where the event isn't exposed yet and inherited events. | |
4098 | */ | |
4099 | static void free_event(struct perf_event *event) | |
0793a61d | 4100 | { |
683ede43 PZ |
4101 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4102 | "unexpected event refcount: %ld; ptr=%p\n", | |
4103 | atomic_long_read(&event->refcount), event)) { | |
4104 | /* leak to avoid use-after-free */ | |
4105 | return; | |
4106 | } | |
0793a61d | 4107 | |
683ede43 | 4108 | _free_event(event); |
0793a61d TG |
4109 | } |
4110 | ||
a66a3052 | 4111 | /* |
f8697762 | 4112 | * Remove user event from the owner task. |
a66a3052 | 4113 | */ |
f8697762 | 4114 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4115 | { |
8882135b | 4116 | struct task_struct *owner; |
fb0459d7 | 4117 | |
8882135b | 4118 | rcu_read_lock(); |
8882135b | 4119 | /* |
f47c02c0 PZ |
4120 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4121 | * observe !owner it means the list deletion is complete and we can | |
4122 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4123 | * owner->perf_event_mutex. |
4124 | */ | |
f47c02c0 | 4125 | owner = lockless_dereference(event->owner); |
8882135b PZ |
4126 | if (owner) { |
4127 | /* | |
4128 | * Since delayed_put_task_struct() also drops the last | |
4129 | * task reference we can safely take a new reference | |
4130 | * while holding the rcu_read_lock(). | |
4131 | */ | |
4132 | get_task_struct(owner); | |
4133 | } | |
4134 | rcu_read_unlock(); | |
4135 | ||
4136 | if (owner) { | |
f63a8daa PZ |
4137 | /* |
4138 | * If we're here through perf_event_exit_task() we're already | |
4139 | * holding ctx->mutex which would be an inversion wrt. the | |
4140 | * normal lock order. | |
4141 | * | |
4142 | * However we can safely take this lock because its the child | |
4143 | * ctx->mutex. | |
4144 | */ | |
4145 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4146 | ||
8882135b PZ |
4147 | /* |
4148 | * We have to re-check the event->owner field, if it is cleared | |
4149 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4150 | * ensured they're done, and we can proceed with freeing the | |
4151 | * event. | |
4152 | */ | |
f47c02c0 | 4153 | if (event->owner) { |
8882135b | 4154 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4155 | smp_store_release(&event->owner, NULL); |
4156 | } | |
8882135b PZ |
4157 | mutex_unlock(&owner->perf_event_mutex); |
4158 | put_task_struct(owner); | |
4159 | } | |
f8697762 JO |
4160 | } |
4161 | ||
f8697762 JO |
4162 | static void put_event(struct perf_event *event) |
4163 | { | |
f8697762 JO |
4164 | if (!atomic_long_dec_and_test(&event->refcount)) |
4165 | return; | |
4166 | ||
c6e5b732 PZ |
4167 | _free_event(event); |
4168 | } | |
4169 | ||
4170 | /* | |
4171 | * Kill an event dead; while event:refcount will preserve the event | |
4172 | * object, it will not preserve its functionality. Once the last 'user' | |
4173 | * gives up the object, we'll destroy the thing. | |
4174 | */ | |
4175 | int perf_event_release_kernel(struct perf_event *event) | |
4176 | { | |
a4f4bb6d | 4177 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4178 | struct perf_event *child, *tmp; |
4179 | ||
a4f4bb6d PZ |
4180 | /* |
4181 | * If we got here through err_file: fput(event_file); we will not have | |
4182 | * attached to a context yet. | |
4183 | */ | |
4184 | if (!ctx) { | |
4185 | WARN_ON_ONCE(event->attach_state & | |
4186 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4187 | goto no_ctx; | |
4188 | } | |
4189 | ||
f8697762 JO |
4190 | if (!is_kernel_event(event)) |
4191 | perf_remove_from_owner(event); | |
8882135b | 4192 | |
5fa7c8ec | 4193 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4194 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4195 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4196 | |
a69b0ca4 | 4197 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4198 | /* |
a69b0ca4 PZ |
4199 | * Mark this even as STATE_DEAD, there is no external reference to it |
4200 | * anymore. | |
683ede43 | 4201 | * |
a69b0ca4 PZ |
4202 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4203 | * also see this, most importantly inherit_event() which will avoid | |
4204 | * placing more children on the list. | |
683ede43 | 4205 | * |
c6e5b732 PZ |
4206 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4207 | * child events. | |
683ede43 | 4208 | */ |
a69b0ca4 PZ |
4209 | event->state = PERF_EVENT_STATE_DEAD; |
4210 | raw_spin_unlock_irq(&ctx->lock); | |
4211 | ||
4212 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4213 | |
c6e5b732 PZ |
4214 | again: |
4215 | mutex_lock(&event->child_mutex); | |
4216 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4217 | |
c6e5b732 PZ |
4218 | /* |
4219 | * Cannot change, child events are not migrated, see the | |
4220 | * comment with perf_event_ctx_lock_nested(). | |
4221 | */ | |
4222 | ctx = lockless_dereference(child->ctx); | |
4223 | /* | |
4224 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4225 | * through hoops. We start by grabbing a reference on the ctx. | |
4226 | * | |
4227 | * Since the event cannot get freed while we hold the | |
4228 | * child_mutex, the context must also exist and have a !0 | |
4229 | * reference count. | |
4230 | */ | |
4231 | get_ctx(ctx); | |
4232 | ||
4233 | /* | |
4234 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4235 | * acquire ctx::mutex without fear of it going away. Then we | |
4236 | * can re-acquire child_mutex. | |
4237 | */ | |
4238 | mutex_unlock(&event->child_mutex); | |
4239 | mutex_lock(&ctx->mutex); | |
4240 | mutex_lock(&event->child_mutex); | |
4241 | ||
4242 | /* | |
4243 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4244 | * state, if child is still the first entry, it didn't get freed | |
4245 | * and we can continue doing so. | |
4246 | */ | |
4247 | tmp = list_first_entry_or_null(&event->child_list, | |
4248 | struct perf_event, child_list); | |
4249 | if (tmp == child) { | |
4250 | perf_remove_from_context(child, DETACH_GROUP); | |
4251 | list_del(&child->child_list); | |
4252 | free_event(child); | |
4253 | /* | |
4254 | * This matches the refcount bump in inherit_event(); | |
4255 | * this can't be the last reference. | |
4256 | */ | |
4257 | put_event(event); | |
4258 | } | |
4259 | ||
4260 | mutex_unlock(&event->child_mutex); | |
4261 | mutex_unlock(&ctx->mutex); | |
4262 | put_ctx(ctx); | |
4263 | goto again; | |
4264 | } | |
4265 | mutex_unlock(&event->child_mutex); | |
4266 | ||
a4f4bb6d PZ |
4267 | no_ctx: |
4268 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4269 | return 0; |
4270 | } | |
4271 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4272 | ||
8b10c5e2 PZ |
4273 | /* |
4274 | * Called when the last reference to the file is gone. | |
4275 | */ | |
a6fa941d AV |
4276 | static int perf_release(struct inode *inode, struct file *file) |
4277 | { | |
c6e5b732 | 4278 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4279 | return 0; |
fb0459d7 | 4280 | } |
fb0459d7 | 4281 | |
59ed446f | 4282 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4283 | { |
cdd6c482 | 4284 | struct perf_event *child; |
e53c0994 PZ |
4285 | u64 total = 0; |
4286 | ||
59ed446f PZ |
4287 | *enabled = 0; |
4288 | *running = 0; | |
4289 | ||
6f10581a | 4290 | mutex_lock(&event->child_mutex); |
01add3ea | 4291 | |
7d88962e | 4292 | (void)perf_event_read(event, false); |
01add3ea SB |
4293 | total += perf_event_count(event); |
4294 | ||
59ed446f PZ |
4295 | *enabled += event->total_time_enabled + |
4296 | atomic64_read(&event->child_total_time_enabled); | |
4297 | *running += event->total_time_running + | |
4298 | atomic64_read(&event->child_total_time_running); | |
4299 | ||
4300 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4301 | (void)perf_event_read(child, false); |
01add3ea | 4302 | total += perf_event_count(child); |
59ed446f PZ |
4303 | *enabled += child->total_time_enabled; |
4304 | *running += child->total_time_running; | |
4305 | } | |
6f10581a | 4306 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4307 | |
4308 | return total; | |
4309 | } | |
fb0459d7 | 4310 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4311 | |
7d88962e | 4312 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4313 | u64 read_format, u64 *values) |
3dab77fb | 4314 | { |
fa8c2693 PZ |
4315 | struct perf_event *sub; |
4316 | int n = 1; /* skip @nr */ | |
7d88962e | 4317 | int ret; |
f63a8daa | 4318 | |
7d88962e SB |
4319 | ret = perf_event_read(leader, true); |
4320 | if (ret) | |
4321 | return ret; | |
abf4868b | 4322 | |
fa8c2693 PZ |
4323 | /* |
4324 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4325 | * will be identical to those of the leader, so we only publish one | |
4326 | * set. | |
4327 | */ | |
4328 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4329 | values[n++] += leader->total_time_enabled + | |
4330 | atomic64_read(&leader->child_total_time_enabled); | |
4331 | } | |
3dab77fb | 4332 | |
fa8c2693 PZ |
4333 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4334 | values[n++] += leader->total_time_running + | |
4335 | atomic64_read(&leader->child_total_time_running); | |
4336 | } | |
4337 | ||
4338 | /* | |
4339 | * Write {count,id} tuples for every sibling. | |
4340 | */ | |
4341 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4342 | if (read_format & PERF_FORMAT_ID) |
4343 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4344 | |
fa8c2693 PZ |
4345 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4346 | values[n++] += perf_event_count(sub); | |
4347 | if (read_format & PERF_FORMAT_ID) | |
4348 | values[n++] = primary_event_id(sub); | |
4349 | } | |
7d88962e SB |
4350 | |
4351 | return 0; | |
fa8c2693 | 4352 | } |
3dab77fb | 4353 | |
fa8c2693 PZ |
4354 | static int perf_read_group(struct perf_event *event, |
4355 | u64 read_format, char __user *buf) | |
4356 | { | |
4357 | struct perf_event *leader = event->group_leader, *child; | |
4358 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4359 | int ret; |
fa8c2693 | 4360 | u64 *values; |
3dab77fb | 4361 | |
fa8c2693 | 4362 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4363 | |
fa8c2693 PZ |
4364 | values = kzalloc(event->read_size, GFP_KERNEL); |
4365 | if (!values) | |
4366 | return -ENOMEM; | |
3dab77fb | 4367 | |
fa8c2693 PZ |
4368 | values[0] = 1 + leader->nr_siblings; |
4369 | ||
4370 | /* | |
4371 | * By locking the child_mutex of the leader we effectively | |
4372 | * lock the child list of all siblings.. XXX explain how. | |
4373 | */ | |
4374 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4375 | |
7d88962e SB |
4376 | ret = __perf_read_group_add(leader, read_format, values); |
4377 | if (ret) | |
4378 | goto unlock; | |
4379 | ||
4380 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4381 | ret = __perf_read_group_add(child, read_format, values); | |
4382 | if (ret) | |
4383 | goto unlock; | |
4384 | } | |
abf4868b | 4385 | |
fa8c2693 | 4386 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4387 | |
7d88962e | 4388 | ret = event->read_size; |
fa8c2693 PZ |
4389 | if (copy_to_user(buf, values, event->read_size)) |
4390 | ret = -EFAULT; | |
7d88962e | 4391 | goto out; |
fa8c2693 | 4392 | |
7d88962e SB |
4393 | unlock: |
4394 | mutex_unlock(&leader->child_mutex); | |
4395 | out: | |
fa8c2693 | 4396 | kfree(values); |
abf4868b | 4397 | return ret; |
3dab77fb PZ |
4398 | } |
4399 | ||
b15f495b | 4400 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4401 | u64 read_format, char __user *buf) |
4402 | { | |
59ed446f | 4403 | u64 enabled, running; |
3dab77fb PZ |
4404 | u64 values[4]; |
4405 | int n = 0; | |
4406 | ||
59ed446f PZ |
4407 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4408 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4409 | values[n++] = enabled; | |
4410 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4411 | values[n++] = running; | |
3dab77fb | 4412 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4413 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4414 | |
4415 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4416 | return -EFAULT; | |
4417 | ||
4418 | return n * sizeof(u64); | |
4419 | } | |
4420 | ||
dc633982 JO |
4421 | static bool is_event_hup(struct perf_event *event) |
4422 | { | |
4423 | bool no_children; | |
4424 | ||
a69b0ca4 | 4425 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4426 | return false; |
4427 | ||
4428 | mutex_lock(&event->child_mutex); | |
4429 | no_children = list_empty(&event->child_list); | |
4430 | mutex_unlock(&event->child_mutex); | |
4431 | return no_children; | |
4432 | } | |
4433 | ||
0793a61d | 4434 | /* |
cdd6c482 | 4435 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4436 | */ |
4437 | static ssize_t | |
b15f495b | 4438 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4439 | { |
cdd6c482 | 4440 | u64 read_format = event->attr.read_format; |
3dab77fb | 4441 | int ret; |
0793a61d | 4442 | |
3b6f9e5c | 4443 | /* |
cdd6c482 | 4444 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4445 | * error state (i.e. because it was pinned but it couldn't be |
4446 | * scheduled on to the CPU at some point). | |
4447 | */ | |
cdd6c482 | 4448 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4449 | return 0; |
4450 | ||
c320c7b7 | 4451 | if (count < event->read_size) |
3dab77fb PZ |
4452 | return -ENOSPC; |
4453 | ||
cdd6c482 | 4454 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4455 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4456 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4457 | else |
b15f495b | 4458 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4459 | |
3dab77fb | 4460 | return ret; |
0793a61d TG |
4461 | } |
4462 | ||
0793a61d TG |
4463 | static ssize_t |
4464 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4465 | { | |
cdd6c482 | 4466 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4467 | struct perf_event_context *ctx; |
4468 | int ret; | |
0793a61d | 4469 | |
f63a8daa | 4470 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4471 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4472 | perf_event_ctx_unlock(event, ctx); |
4473 | ||
4474 | return ret; | |
0793a61d TG |
4475 | } |
4476 | ||
4477 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4478 | { | |
cdd6c482 | 4479 | struct perf_event *event = file->private_data; |
76369139 | 4480 | struct ring_buffer *rb; |
61b67684 | 4481 | unsigned int events = POLLHUP; |
c7138f37 | 4482 | |
e708d7ad | 4483 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4484 | |
dc633982 | 4485 | if (is_event_hup(event)) |
179033b3 | 4486 | return events; |
c7138f37 | 4487 | |
10c6db11 | 4488 | /* |
9bb5d40c PZ |
4489 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4490 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4491 | */ |
4492 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4493 | rb = event->rb; |
4494 | if (rb) | |
76369139 | 4495 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4496 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4497 | return events; |
4498 | } | |
4499 | ||
f63a8daa | 4500 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4501 | { |
7d88962e | 4502 | (void)perf_event_read(event, false); |
e7850595 | 4503 | local64_set(&event->count, 0); |
cdd6c482 | 4504 | perf_event_update_userpage(event); |
3df5edad PZ |
4505 | } |
4506 | ||
c93f7669 | 4507 | /* |
cdd6c482 IM |
4508 | * Holding the top-level event's child_mutex means that any |
4509 | * descendant process that has inherited this event will block | |
8ba289b8 | 4510 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4511 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4512 | */ |
cdd6c482 IM |
4513 | static void perf_event_for_each_child(struct perf_event *event, |
4514 | void (*func)(struct perf_event *)) | |
3df5edad | 4515 | { |
cdd6c482 | 4516 | struct perf_event *child; |
3df5edad | 4517 | |
cdd6c482 | 4518 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4519 | |
cdd6c482 IM |
4520 | mutex_lock(&event->child_mutex); |
4521 | func(event); | |
4522 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4523 | func(child); |
cdd6c482 | 4524 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4525 | } |
4526 | ||
cdd6c482 IM |
4527 | static void perf_event_for_each(struct perf_event *event, |
4528 | void (*func)(struct perf_event *)) | |
3df5edad | 4529 | { |
cdd6c482 IM |
4530 | struct perf_event_context *ctx = event->ctx; |
4531 | struct perf_event *sibling; | |
3df5edad | 4532 | |
f63a8daa PZ |
4533 | lockdep_assert_held(&ctx->mutex); |
4534 | ||
cdd6c482 | 4535 | event = event->group_leader; |
75f937f2 | 4536 | |
cdd6c482 | 4537 | perf_event_for_each_child(event, func); |
cdd6c482 | 4538 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4539 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4540 | } |
4541 | ||
fae3fde6 PZ |
4542 | static void __perf_event_period(struct perf_event *event, |
4543 | struct perf_cpu_context *cpuctx, | |
4544 | struct perf_event_context *ctx, | |
4545 | void *info) | |
c7999c6f | 4546 | { |
fae3fde6 | 4547 | u64 value = *((u64 *)info); |
c7999c6f | 4548 | bool active; |
08247e31 | 4549 | |
cdd6c482 | 4550 | if (event->attr.freq) { |
cdd6c482 | 4551 | event->attr.sample_freq = value; |
08247e31 | 4552 | } else { |
cdd6c482 IM |
4553 | event->attr.sample_period = value; |
4554 | event->hw.sample_period = value; | |
08247e31 | 4555 | } |
bad7192b PZ |
4556 | |
4557 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4558 | if (active) { | |
4559 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4560 | /* |
4561 | * We could be throttled; unthrottle now to avoid the tick | |
4562 | * trying to unthrottle while we already re-started the event. | |
4563 | */ | |
4564 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4565 | event->hw.interrupts = 0; | |
4566 | perf_log_throttle(event, 1); | |
4567 | } | |
bad7192b PZ |
4568 | event->pmu->stop(event, PERF_EF_UPDATE); |
4569 | } | |
4570 | ||
4571 | local64_set(&event->hw.period_left, 0); | |
4572 | ||
4573 | if (active) { | |
4574 | event->pmu->start(event, PERF_EF_RELOAD); | |
4575 | perf_pmu_enable(ctx->pmu); | |
4576 | } | |
c7999c6f PZ |
4577 | } |
4578 | ||
4579 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4580 | { | |
c7999c6f PZ |
4581 | u64 value; |
4582 | ||
4583 | if (!is_sampling_event(event)) | |
4584 | return -EINVAL; | |
4585 | ||
4586 | if (copy_from_user(&value, arg, sizeof(value))) | |
4587 | return -EFAULT; | |
4588 | ||
4589 | if (!value) | |
4590 | return -EINVAL; | |
4591 | ||
4592 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4593 | return -EINVAL; | |
4594 | ||
fae3fde6 | 4595 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4596 | |
c7999c6f | 4597 | return 0; |
08247e31 PZ |
4598 | } |
4599 | ||
ac9721f3 PZ |
4600 | static const struct file_operations perf_fops; |
4601 | ||
2903ff01 | 4602 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4603 | { |
2903ff01 AV |
4604 | struct fd f = fdget(fd); |
4605 | if (!f.file) | |
4606 | return -EBADF; | |
ac9721f3 | 4607 | |
2903ff01 AV |
4608 | if (f.file->f_op != &perf_fops) { |
4609 | fdput(f); | |
4610 | return -EBADF; | |
ac9721f3 | 4611 | } |
2903ff01 AV |
4612 | *p = f; |
4613 | return 0; | |
ac9721f3 PZ |
4614 | } |
4615 | ||
4616 | static int perf_event_set_output(struct perf_event *event, | |
4617 | struct perf_event *output_event); | |
6fb2915d | 4618 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4619 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4620 | |
f63a8daa | 4621 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4622 | { |
cdd6c482 | 4623 | void (*func)(struct perf_event *); |
3df5edad | 4624 | u32 flags = arg; |
d859e29f PM |
4625 | |
4626 | switch (cmd) { | |
cdd6c482 | 4627 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4628 | func = _perf_event_enable; |
d859e29f | 4629 | break; |
cdd6c482 | 4630 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4631 | func = _perf_event_disable; |
79f14641 | 4632 | break; |
cdd6c482 | 4633 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4634 | func = _perf_event_reset; |
6de6a7b9 | 4635 | break; |
3df5edad | 4636 | |
cdd6c482 | 4637 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4638 | return _perf_event_refresh(event, arg); |
08247e31 | 4639 | |
cdd6c482 IM |
4640 | case PERF_EVENT_IOC_PERIOD: |
4641 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4642 | |
cf4957f1 JO |
4643 | case PERF_EVENT_IOC_ID: |
4644 | { | |
4645 | u64 id = primary_event_id(event); | |
4646 | ||
4647 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4648 | return -EFAULT; | |
4649 | return 0; | |
4650 | } | |
4651 | ||
cdd6c482 | 4652 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4653 | { |
ac9721f3 | 4654 | int ret; |
ac9721f3 | 4655 | if (arg != -1) { |
2903ff01 AV |
4656 | struct perf_event *output_event; |
4657 | struct fd output; | |
4658 | ret = perf_fget_light(arg, &output); | |
4659 | if (ret) | |
4660 | return ret; | |
4661 | output_event = output.file->private_data; | |
4662 | ret = perf_event_set_output(event, output_event); | |
4663 | fdput(output); | |
4664 | } else { | |
4665 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4666 | } |
ac9721f3 PZ |
4667 | return ret; |
4668 | } | |
a4be7c27 | 4669 | |
6fb2915d LZ |
4670 | case PERF_EVENT_IOC_SET_FILTER: |
4671 | return perf_event_set_filter(event, (void __user *)arg); | |
4672 | ||
2541517c AS |
4673 | case PERF_EVENT_IOC_SET_BPF: |
4674 | return perf_event_set_bpf_prog(event, arg); | |
4675 | ||
86e7972f WN |
4676 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4677 | struct ring_buffer *rb; | |
4678 | ||
4679 | rcu_read_lock(); | |
4680 | rb = rcu_dereference(event->rb); | |
4681 | if (!rb || !rb->nr_pages) { | |
4682 | rcu_read_unlock(); | |
4683 | return -EINVAL; | |
4684 | } | |
4685 | rb_toggle_paused(rb, !!arg); | |
4686 | rcu_read_unlock(); | |
4687 | return 0; | |
4688 | } | |
d859e29f | 4689 | default: |
3df5edad | 4690 | return -ENOTTY; |
d859e29f | 4691 | } |
3df5edad PZ |
4692 | |
4693 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4694 | perf_event_for_each(event, func); |
3df5edad | 4695 | else |
cdd6c482 | 4696 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4697 | |
4698 | return 0; | |
d859e29f PM |
4699 | } |
4700 | ||
f63a8daa PZ |
4701 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4702 | { | |
4703 | struct perf_event *event = file->private_data; | |
4704 | struct perf_event_context *ctx; | |
4705 | long ret; | |
4706 | ||
4707 | ctx = perf_event_ctx_lock(event); | |
4708 | ret = _perf_ioctl(event, cmd, arg); | |
4709 | perf_event_ctx_unlock(event, ctx); | |
4710 | ||
4711 | return ret; | |
4712 | } | |
4713 | ||
b3f20785 PM |
4714 | #ifdef CONFIG_COMPAT |
4715 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4716 | unsigned long arg) | |
4717 | { | |
4718 | switch (_IOC_NR(cmd)) { | |
4719 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4720 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4721 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4722 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4723 | cmd &= ~IOCSIZE_MASK; | |
4724 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4725 | } | |
4726 | break; | |
4727 | } | |
4728 | return perf_ioctl(file, cmd, arg); | |
4729 | } | |
4730 | #else | |
4731 | # define perf_compat_ioctl NULL | |
4732 | #endif | |
4733 | ||
cdd6c482 | 4734 | int perf_event_task_enable(void) |
771d7cde | 4735 | { |
f63a8daa | 4736 | struct perf_event_context *ctx; |
cdd6c482 | 4737 | struct perf_event *event; |
771d7cde | 4738 | |
cdd6c482 | 4739 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4740 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4741 | ctx = perf_event_ctx_lock(event); | |
4742 | perf_event_for_each_child(event, _perf_event_enable); | |
4743 | perf_event_ctx_unlock(event, ctx); | |
4744 | } | |
cdd6c482 | 4745 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4746 | |
4747 | return 0; | |
4748 | } | |
4749 | ||
cdd6c482 | 4750 | int perf_event_task_disable(void) |
771d7cde | 4751 | { |
f63a8daa | 4752 | struct perf_event_context *ctx; |
cdd6c482 | 4753 | struct perf_event *event; |
771d7cde | 4754 | |
cdd6c482 | 4755 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4756 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4757 | ctx = perf_event_ctx_lock(event); | |
4758 | perf_event_for_each_child(event, _perf_event_disable); | |
4759 | perf_event_ctx_unlock(event, ctx); | |
4760 | } | |
cdd6c482 | 4761 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4762 | |
4763 | return 0; | |
4764 | } | |
4765 | ||
cdd6c482 | 4766 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4767 | { |
a4eaf7f1 PZ |
4768 | if (event->hw.state & PERF_HES_STOPPED) |
4769 | return 0; | |
4770 | ||
cdd6c482 | 4771 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4772 | return 0; |
4773 | ||
35edc2a5 | 4774 | return event->pmu->event_idx(event); |
194002b2 PZ |
4775 | } |
4776 | ||
c4794295 | 4777 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4778 | u64 *now, |
7f310a5d EM |
4779 | u64 *enabled, |
4780 | u64 *running) | |
c4794295 | 4781 | { |
e3f3541c | 4782 | u64 ctx_time; |
c4794295 | 4783 | |
e3f3541c PZ |
4784 | *now = perf_clock(); |
4785 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4786 | *enabled = ctx_time - event->tstamp_enabled; |
4787 | *running = ctx_time - event->tstamp_running; | |
4788 | } | |
4789 | ||
fa731587 PZ |
4790 | static void perf_event_init_userpage(struct perf_event *event) |
4791 | { | |
4792 | struct perf_event_mmap_page *userpg; | |
4793 | struct ring_buffer *rb; | |
4794 | ||
4795 | rcu_read_lock(); | |
4796 | rb = rcu_dereference(event->rb); | |
4797 | if (!rb) | |
4798 | goto unlock; | |
4799 | ||
4800 | userpg = rb->user_page; | |
4801 | ||
4802 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4803 | userpg->cap_bit0_is_deprecated = 1; | |
4804 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4805 | userpg->data_offset = PAGE_SIZE; |
4806 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4807 | |
4808 | unlock: | |
4809 | rcu_read_unlock(); | |
4810 | } | |
4811 | ||
c1317ec2 AL |
4812 | void __weak arch_perf_update_userpage( |
4813 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4814 | { |
4815 | } | |
4816 | ||
38ff667b PZ |
4817 | /* |
4818 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4819 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4820 | * code calls this from NMI context. | |
4821 | */ | |
cdd6c482 | 4822 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4823 | { |
cdd6c482 | 4824 | struct perf_event_mmap_page *userpg; |
76369139 | 4825 | struct ring_buffer *rb; |
e3f3541c | 4826 | u64 enabled, running, now; |
38ff667b PZ |
4827 | |
4828 | rcu_read_lock(); | |
5ec4c599 PZ |
4829 | rb = rcu_dereference(event->rb); |
4830 | if (!rb) | |
4831 | goto unlock; | |
4832 | ||
0d641208 EM |
4833 | /* |
4834 | * compute total_time_enabled, total_time_running | |
4835 | * based on snapshot values taken when the event | |
4836 | * was last scheduled in. | |
4837 | * | |
4838 | * we cannot simply called update_context_time() | |
4839 | * because of locking issue as we can be called in | |
4840 | * NMI context | |
4841 | */ | |
e3f3541c | 4842 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4843 | |
76369139 | 4844 | userpg = rb->user_page; |
7b732a75 PZ |
4845 | /* |
4846 | * Disable preemption so as to not let the corresponding user-space | |
4847 | * spin too long if we get preempted. | |
4848 | */ | |
4849 | preempt_disable(); | |
37d81828 | 4850 | ++userpg->lock; |
92f22a38 | 4851 | barrier(); |
cdd6c482 | 4852 | userpg->index = perf_event_index(event); |
b5e58793 | 4853 | userpg->offset = perf_event_count(event); |
365a4038 | 4854 | if (userpg->index) |
e7850595 | 4855 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4856 | |
0d641208 | 4857 | userpg->time_enabled = enabled + |
cdd6c482 | 4858 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4859 | |
0d641208 | 4860 | userpg->time_running = running + |
cdd6c482 | 4861 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4862 | |
c1317ec2 | 4863 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4864 | |
92f22a38 | 4865 | barrier(); |
37d81828 | 4866 | ++userpg->lock; |
7b732a75 | 4867 | preempt_enable(); |
38ff667b | 4868 | unlock: |
7b732a75 | 4869 | rcu_read_unlock(); |
37d81828 PM |
4870 | } |
4871 | ||
906010b2 PZ |
4872 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4873 | { | |
4874 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4875 | struct ring_buffer *rb; |
906010b2 PZ |
4876 | int ret = VM_FAULT_SIGBUS; |
4877 | ||
4878 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4879 | if (vmf->pgoff == 0) | |
4880 | ret = 0; | |
4881 | return ret; | |
4882 | } | |
4883 | ||
4884 | rcu_read_lock(); | |
76369139 FW |
4885 | rb = rcu_dereference(event->rb); |
4886 | if (!rb) | |
906010b2 PZ |
4887 | goto unlock; |
4888 | ||
4889 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4890 | goto unlock; | |
4891 | ||
76369139 | 4892 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4893 | if (!vmf->page) |
4894 | goto unlock; | |
4895 | ||
4896 | get_page(vmf->page); | |
4897 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4898 | vmf->page->index = vmf->pgoff; | |
4899 | ||
4900 | ret = 0; | |
4901 | unlock: | |
4902 | rcu_read_unlock(); | |
4903 | ||
4904 | return ret; | |
4905 | } | |
4906 | ||
10c6db11 PZ |
4907 | static void ring_buffer_attach(struct perf_event *event, |
4908 | struct ring_buffer *rb) | |
4909 | { | |
b69cf536 | 4910 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4911 | unsigned long flags; |
4912 | ||
b69cf536 PZ |
4913 | if (event->rb) { |
4914 | /* | |
4915 | * Should be impossible, we set this when removing | |
4916 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4917 | */ | |
4918 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4919 | |
b69cf536 | 4920 | old_rb = event->rb; |
b69cf536 PZ |
4921 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4922 | list_del_rcu(&event->rb_entry); | |
4923 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4924 | |
2f993cf0 ON |
4925 | event->rcu_batches = get_state_synchronize_rcu(); |
4926 | event->rcu_pending = 1; | |
b69cf536 | 4927 | } |
10c6db11 | 4928 | |
b69cf536 | 4929 | if (rb) { |
2f993cf0 ON |
4930 | if (event->rcu_pending) { |
4931 | cond_synchronize_rcu(event->rcu_batches); | |
4932 | event->rcu_pending = 0; | |
4933 | } | |
4934 | ||
b69cf536 PZ |
4935 | spin_lock_irqsave(&rb->event_lock, flags); |
4936 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4937 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4938 | } | |
4939 | ||
767ae086 AS |
4940 | /* |
4941 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
4942 | * before swizzling the event::rb pointer; if it's getting | |
4943 | * unmapped, its aux_mmap_count will be 0 and it won't | |
4944 | * restart. See the comment in __perf_pmu_output_stop(). | |
4945 | * | |
4946 | * Data will inevitably be lost when set_output is done in | |
4947 | * mid-air, but then again, whoever does it like this is | |
4948 | * not in for the data anyway. | |
4949 | */ | |
4950 | if (has_aux(event)) | |
4951 | perf_event_stop(event, 0); | |
4952 | ||
b69cf536 PZ |
4953 | rcu_assign_pointer(event->rb, rb); |
4954 | ||
4955 | if (old_rb) { | |
4956 | ring_buffer_put(old_rb); | |
4957 | /* | |
4958 | * Since we detached before setting the new rb, so that we | |
4959 | * could attach the new rb, we could have missed a wakeup. | |
4960 | * Provide it now. | |
4961 | */ | |
4962 | wake_up_all(&event->waitq); | |
4963 | } | |
10c6db11 PZ |
4964 | } |
4965 | ||
4966 | static void ring_buffer_wakeup(struct perf_event *event) | |
4967 | { | |
4968 | struct ring_buffer *rb; | |
4969 | ||
4970 | rcu_read_lock(); | |
4971 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4972 | if (rb) { |
4973 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4974 | wake_up_all(&event->waitq); | |
4975 | } | |
10c6db11 PZ |
4976 | rcu_read_unlock(); |
4977 | } | |
4978 | ||
fdc26706 | 4979 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4980 | { |
76369139 | 4981 | struct ring_buffer *rb; |
7b732a75 | 4982 | |
ac9721f3 | 4983 | rcu_read_lock(); |
76369139 FW |
4984 | rb = rcu_dereference(event->rb); |
4985 | if (rb) { | |
4986 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4987 | rb = NULL; | |
ac9721f3 PZ |
4988 | } |
4989 | rcu_read_unlock(); | |
4990 | ||
76369139 | 4991 | return rb; |
ac9721f3 PZ |
4992 | } |
4993 | ||
fdc26706 | 4994 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4995 | { |
76369139 | 4996 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4997 | return; |
7b732a75 | 4998 | |
9bb5d40c | 4999 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5000 | |
76369139 | 5001 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5002 | } |
5003 | ||
5004 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5005 | { | |
cdd6c482 | 5006 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5007 | |
cdd6c482 | 5008 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5009 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5010 | |
45bfb2e5 PZ |
5011 | if (vma->vm_pgoff) |
5012 | atomic_inc(&event->rb->aux_mmap_count); | |
5013 | ||
1e0fb9ec AL |
5014 | if (event->pmu->event_mapped) |
5015 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
5016 | } |
5017 | ||
95ff4ca2 AS |
5018 | static void perf_pmu_output_stop(struct perf_event *event); |
5019 | ||
9bb5d40c PZ |
5020 | /* |
5021 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5022 | * event, or through other events by use of perf_event_set_output(). | |
5023 | * | |
5024 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5025 | * the buffer here, where we still have a VM context. This means we need | |
5026 | * to detach all events redirecting to us. | |
5027 | */ | |
7b732a75 PZ |
5028 | static void perf_mmap_close(struct vm_area_struct *vma) |
5029 | { | |
cdd6c482 | 5030 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5031 | |
b69cf536 | 5032 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5033 | struct user_struct *mmap_user = rb->mmap_user; |
5034 | int mmap_locked = rb->mmap_locked; | |
5035 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5036 | |
1e0fb9ec AL |
5037 | if (event->pmu->event_unmapped) |
5038 | event->pmu->event_unmapped(event); | |
5039 | ||
45bfb2e5 PZ |
5040 | /* |
5041 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5042 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5043 | * serialize with perf_mmap here. | |
5044 | */ | |
5045 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5046 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5047 | /* |
5048 | * Stop all AUX events that are writing to this buffer, | |
5049 | * so that we can free its AUX pages and corresponding PMU | |
5050 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5051 | * they won't start any more (see perf_aux_output_begin()). | |
5052 | */ | |
5053 | perf_pmu_output_stop(event); | |
5054 | ||
5055 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5056 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5057 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5058 | ||
95ff4ca2 | 5059 | /* this has to be the last one */ |
45bfb2e5 | 5060 | rb_free_aux(rb); |
95ff4ca2 AS |
5061 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5062 | ||
45bfb2e5 PZ |
5063 | mutex_unlock(&event->mmap_mutex); |
5064 | } | |
5065 | ||
9bb5d40c PZ |
5066 | atomic_dec(&rb->mmap_count); |
5067 | ||
5068 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5069 | goto out_put; |
9bb5d40c | 5070 | |
b69cf536 | 5071 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5072 | mutex_unlock(&event->mmap_mutex); |
5073 | ||
5074 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5075 | if (atomic_read(&rb->mmap_count)) |
5076 | goto out_put; | |
ac9721f3 | 5077 | |
9bb5d40c PZ |
5078 | /* |
5079 | * No other mmap()s, detach from all other events that might redirect | |
5080 | * into the now unreachable buffer. Somewhat complicated by the | |
5081 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5082 | */ | |
5083 | again: | |
5084 | rcu_read_lock(); | |
5085 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5086 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5087 | /* | |
5088 | * This event is en-route to free_event() which will | |
5089 | * detach it and remove it from the list. | |
5090 | */ | |
5091 | continue; | |
5092 | } | |
5093 | rcu_read_unlock(); | |
789f90fc | 5094 | |
9bb5d40c PZ |
5095 | mutex_lock(&event->mmap_mutex); |
5096 | /* | |
5097 | * Check we didn't race with perf_event_set_output() which can | |
5098 | * swizzle the rb from under us while we were waiting to | |
5099 | * acquire mmap_mutex. | |
5100 | * | |
5101 | * If we find a different rb; ignore this event, a next | |
5102 | * iteration will no longer find it on the list. We have to | |
5103 | * still restart the iteration to make sure we're not now | |
5104 | * iterating the wrong list. | |
5105 | */ | |
b69cf536 PZ |
5106 | if (event->rb == rb) |
5107 | ring_buffer_attach(event, NULL); | |
5108 | ||
cdd6c482 | 5109 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5110 | put_event(event); |
ac9721f3 | 5111 | |
9bb5d40c PZ |
5112 | /* |
5113 | * Restart the iteration; either we're on the wrong list or | |
5114 | * destroyed its integrity by doing a deletion. | |
5115 | */ | |
5116 | goto again; | |
7b732a75 | 5117 | } |
9bb5d40c PZ |
5118 | rcu_read_unlock(); |
5119 | ||
5120 | /* | |
5121 | * It could be there's still a few 0-ref events on the list; they'll | |
5122 | * get cleaned up by free_event() -- they'll also still have their | |
5123 | * ref on the rb and will free it whenever they are done with it. | |
5124 | * | |
5125 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5126 | * undo the VM accounting. | |
5127 | */ | |
5128 | ||
5129 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5130 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5131 | free_uid(mmap_user); | |
5132 | ||
b69cf536 | 5133 | out_put: |
9bb5d40c | 5134 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5135 | } |
5136 | ||
f0f37e2f | 5137 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5138 | .open = perf_mmap_open, |
45bfb2e5 | 5139 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5140 | .fault = perf_mmap_fault, |
5141 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5142 | }; |
5143 | ||
5144 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5145 | { | |
cdd6c482 | 5146 | struct perf_event *event = file->private_data; |
22a4f650 | 5147 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5148 | struct user_struct *user = current_user(); |
22a4f650 | 5149 | unsigned long locked, lock_limit; |
45bfb2e5 | 5150 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5151 | unsigned long vma_size; |
5152 | unsigned long nr_pages; | |
45bfb2e5 | 5153 | long user_extra = 0, extra = 0; |
d57e34fd | 5154 | int ret = 0, flags = 0; |
37d81828 | 5155 | |
c7920614 PZ |
5156 | /* |
5157 | * Don't allow mmap() of inherited per-task counters. This would | |
5158 | * create a performance issue due to all children writing to the | |
76369139 | 5159 | * same rb. |
c7920614 PZ |
5160 | */ |
5161 | if (event->cpu == -1 && event->attr.inherit) | |
5162 | return -EINVAL; | |
5163 | ||
43a21ea8 | 5164 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5165 | return -EINVAL; |
7b732a75 PZ |
5166 | |
5167 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5168 | |
5169 | if (vma->vm_pgoff == 0) { | |
5170 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5171 | } else { | |
5172 | /* | |
5173 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5174 | * mapped, all subsequent mappings should have the same size | |
5175 | * and offset. Must be above the normal perf buffer. | |
5176 | */ | |
5177 | u64 aux_offset, aux_size; | |
5178 | ||
5179 | if (!event->rb) | |
5180 | return -EINVAL; | |
5181 | ||
5182 | nr_pages = vma_size / PAGE_SIZE; | |
5183 | ||
5184 | mutex_lock(&event->mmap_mutex); | |
5185 | ret = -EINVAL; | |
5186 | ||
5187 | rb = event->rb; | |
5188 | if (!rb) | |
5189 | goto aux_unlock; | |
5190 | ||
5191 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5192 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5193 | ||
5194 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5195 | goto aux_unlock; | |
5196 | ||
5197 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5198 | goto aux_unlock; | |
5199 | ||
5200 | /* already mapped with a different offset */ | |
5201 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5202 | goto aux_unlock; | |
5203 | ||
5204 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5205 | goto aux_unlock; | |
5206 | ||
5207 | /* already mapped with a different size */ | |
5208 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5209 | goto aux_unlock; | |
5210 | ||
5211 | if (!is_power_of_2(nr_pages)) | |
5212 | goto aux_unlock; | |
5213 | ||
5214 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5215 | goto aux_unlock; | |
5216 | ||
5217 | if (rb_has_aux(rb)) { | |
5218 | atomic_inc(&rb->aux_mmap_count); | |
5219 | ret = 0; | |
5220 | goto unlock; | |
5221 | } | |
5222 | ||
5223 | atomic_set(&rb->aux_mmap_count, 1); | |
5224 | user_extra = nr_pages; | |
5225 | ||
5226 | goto accounting; | |
5227 | } | |
7b732a75 | 5228 | |
7730d865 | 5229 | /* |
76369139 | 5230 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5231 | * can do bitmasks instead of modulo. |
5232 | */ | |
2ed11312 | 5233 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5234 | return -EINVAL; |
5235 | ||
7b732a75 | 5236 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5237 | return -EINVAL; |
5238 | ||
cdd6c482 | 5239 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5240 | again: |
cdd6c482 | 5241 | mutex_lock(&event->mmap_mutex); |
76369139 | 5242 | if (event->rb) { |
9bb5d40c | 5243 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5244 | ret = -EINVAL; |
9bb5d40c PZ |
5245 | goto unlock; |
5246 | } | |
5247 | ||
5248 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5249 | /* | |
5250 | * Raced against perf_mmap_close() through | |
5251 | * perf_event_set_output(). Try again, hope for better | |
5252 | * luck. | |
5253 | */ | |
5254 | mutex_unlock(&event->mmap_mutex); | |
5255 | goto again; | |
5256 | } | |
5257 | ||
ebb3c4c4 PZ |
5258 | goto unlock; |
5259 | } | |
5260 | ||
789f90fc | 5261 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5262 | |
5263 | accounting: | |
cdd6c482 | 5264 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5265 | |
5266 | /* | |
5267 | * Increase the limit linearly with more CPUs: | |
5268 | */ | |
5269 | user_lock_limit *= num_online_cpus(); | |
5270 | ||
789f90fc | 5271 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5272 | |
789f90fc PZ |
5273 | if (user_locked > user_lock_limit) |
5274 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5275 | |
78d7d407 | 5276 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5277 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5278 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5279 | |
459ec28a IM |
5280 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5281 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5282 | ret = -EPERM; |
5283 | goto unlock; | |
5284 | } | |
7b732a75 | 5285 | |
45bfb2e5 | 5286 | WARN_ON(!rb && event->rb); |
906010b2 | 5287 | |
d57e34fd | 5288 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5289 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5290 | |
76369139 | 5291 | if (!rb) { |
45bfb2e5 PZ |
5292 | rb = rb_alloc(nr_pages, |
5293 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5294 | event->cpu, flags); | |
26cb63ad | 5295 | |
45bfb2e5 PZ |
5296 | if (!rb) { |
5297 | ret = -ENOMEM; | |
5298 | goto unlock; | |
5299 | } | |
43a21ea8 | 5300 | |
45bfb2e5 PZ |
5301 | atomic_set(&rb->mmap_count, 1); |
5302 | rb->mmap_user = get_current_user(); | |
5303 | rb->mmap_locked = extra; | |
26cb63ad | 5304 | |
45bfb2e5 | 5305 | ring_buffer_attach(event, rb); |
ac9721f3 | 5306 | |
45bfb2e5 PZ |
5307 | perf_event_init_userpage(event); |
5308 | perf_event_update_userpage(event); | |
5309 | } else { | |
1a594131 AS |
5310 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5311 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5312 | if (!ret) |
5313 | rb->aux_mmap_locked = extra; | |
5314 | } | |
9a0f05cb | 5315 | |
ebb3c4c4 | 5316 | unlock: |
45bfb2e5 PZ |
5317 | if (!ret) { |
5318 | atomic_long_add(user_extra, &user->locked_vm); | |
5319 | vma->vm_mm->pinned_vm += extra; | |
5320 | ||
ac9721f3 | 5321 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5322 | } else if (rb) { |
5323 | atomic_dec(&rb->mmap_count); | |
5324 | } | |
5325 | aux_unlock: | |
cdd6c482 | 5326 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5327 | |
9bb5d40c PZ |
5328 | /* |
5329 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5330 | * vma. | |
5331 | */ | |
26cb63ad | 5332 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5333 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5334 | |
1e0fb9ec AL |
5335 | if (event->pmu->event_mapped) |
5336 | event->pmu->event_mapped(event); | |
5337 | ||
7b732a75 | 5338 | return ret; |
37d81828 PM |
5339 | } |
5340 | ||
3c446b3d PZ |
5341 | static int perf_fasync(int fd, struct file *filp, int on) |
5342 | { | |
496ad9aa | 5343 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5344 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5345 | int retval; |
5346 | ||
5955102c | 5347 | inode_lock(inode); |
cdd6c482 | 5348 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5349 | inode_unlock(inode); |
3c446b3d PZ |
5350 | |
5351 | if (retval < 0) | |
5352 | return retval; | |
5353 | ||
5354 | return 0; | |
5355 | } | |
5356 | ||
0793a61d | 5357 | static const struct file_operations perf_fops = { |
3326c1ce | 5358 | .llseek = no_llseek, |
0793a61d TG |
5359 | .release = perf_release, |
5360 | .read = perf_read, | |
5361 | .poll = perf_poll, | |
d859e29f | 5362 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5363 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5364 | .mmap = perf_mmap, |
3c446b3d | 5365 | .fasync = perf_fasync, |
0793a61d TG |
5366 | }; |
5367 | ||
925d519a | 5368 | /* |
cdd6c482 | 5369 | * Perf event wakeup |
925d519a PZ |
5370 | * |
5371 | * If there's data, ensure we set the poll() state and publish everything | |
5372 | * to user-space before waking everybody up. | |
5373 | */ | |
5374 | ||
fed66e2c PZ |
5375 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5376 | { | |
5377 | /* only the parent has fasync state */ | |
5378 | if (event->parent) | |
5379 | event = event->parent; | |
5380 | return &event->fasync; | |
5381 | } | |
5382 | ||
cdd6c482 | 5383 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5384 | { |
10c6db11 | 5385 | ring_buffer_wakeup(event); |
4c9e2542 | 5386 | |
cdd6c482 | 5387 | if (event->pending_kill) { |
fed66e2c | 5388 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5389 | event->pending_kill = 0; |
4c9e2542 | 5390 | } |
925d519a PZ |
5391 | } |
5392 | ||
e360adbe | 5393 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5394 | { |
cdd6c482 IM |
5395 | struct perf_event *event = container_of(entry, |
5396 | struct perf_event, pending); | |
d525211f PZ |
5397 | int rctx; |
5398 | ||
5399 | rctx = perf_swevent_get_recursion_context(); | |
5400 | /* | |
5401 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5402 | * and we won't recurse 'further'. | |
5403 | */ | |
79f14641 | 5404 | |
cdd6c482 IM |
5405 | if (event->pending_disable) { |
5406 | event->pending_disable = 0; | |
fae3fde6 | 5407 | perf_event_disable_local(event); |
79f14641 PZ |
5408 | } |
5409 | ||
cdd6c482 IM |
5410 | if (event->pending_wakeup) { |
5411 | event->pending_wakeup = 0; | |
5412 | perf_event_wakeup(event); | |
79f14641 | 5413 | } |
d525211f PZ |
5414 | |
5415 | if (rctx >= 0) | |
5416 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5417 | } |
5418 | ||
39447b38 ZY |
5419 | /* |
5420 | * We assume there is only KVM supporting the callbacks. | |
5421 | * Later on, we might change it to a list if there is | |
5422 | * another virtualization implementation supporting the callbacks. | |
5423 | */ | |
5424 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5425 | ||
5426 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5427 | { | |
5428 | perf_guest_cbs = cbs; | |
5429 | return 0; | |
5430 | } | |
5431 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5432 | ||
5433 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5434 | { | |
5435 | perf_guest_cbs = NULL; | |
5436 | return 0; | |
5437 | } | |
5438 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5439 | ||
4018994f JO |
5440 | static void |
5441 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5442 | struct pt_regs *regs, u64 mask) | |
5443 | { | |
5444 | int bit; | |
29dd3288 | 5445 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5446 | |
29dd3288 MS |
5447 | bitmap_from_u64(_mask, mask); |
5448 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5449 | u64 val; |
5450 | ||
5451 | val = perf_reg_value(regs, bit); | |
5452 | perf_output_put(handle, val); | |
5453 | } | |
5454 | } | |
5455 | ||
60e2364e | 5456 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5457 | struct pt_regs *regs, |
5458 | struct pt_regs *regs_user_copy) | |
4018994f | 5459 | { |
88a7c26a AL |
5460 | if (user_mode(regs)) { |
5461 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5462 | regs_user->regs = regs; |
88a7c26a AL |
5463 | } else if (current->mm) { |
5464 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5465 | } else { |
5466 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5467 | regs_user->regs = NULL; | |
4018994f JO |
5468 | } |
5469 | } | |
5470 | ||
60e2364e SE |
5471 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5472 | struct pt_regs *regs) | |
5473 | { | |
5474 | regs_intr->regs = regs; | |
5475 | regs_intr->abi = perf_reg_abi(current); | |
5476 | } | |
5477 | ||
5478 | ||
c5ebcedb JO |
5479 | /* |
5480 | * Get remaining task size from user stack pointer. | |
5481 | * | |
5482 | * It'd be better to take stack vma map and limit this more | |
5483 | * precisly, but there's no way to get it safely under interrupt, | |
5484 | * so using TASK_SIZE as limit. | |
5485 | */ | |
5486 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5487 | { | |
5488 | unsigned long addr = perf_user_stack_pointer(regs); | |
5489 | ||
5490 | if (!addr || addr >= TASK_SIZE) | |
5491 | return 0; | |
5492 | ||
5493 | return TASK_SIZE - addr; | |
5494 | } | |
5495 | ||
5496 | static u16 | |
5497 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5498 | struct pt_regs *regs) | |
5499 | { | |
5500 | u64 task_size; | |
5501 | ||
5502 | /* No regs, no stack pointer, no dump. */ | |
5503 | if (!regs) | |
5504 | return 0; | |
5505 | ||
5506 | /* | |
5507 | * Check if we fit in with the requested stack size into the: | |
5508 | * - TASK_SIZE | |
5509 | * If we don't, we limit the size to the TASK_SIZE. | |
5510 | * | |
5511 | * - remaining sample size | |
5512 | * If we don't, we customize the stack size to | |
5513 | * fit in to the remaining sample size. | |
5514 | */ | |
5515 | ||
5516 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5517 | stack_size = min(stack_size, (u16) task_size); | |
5518 | ||
5519 | /* Current header size plus static size and dynamic size. */ | |
5520 | header_size += 2 * sizeof(u64); | |
5521 | ||
5522 | /* Do we fit in with the current stack dump size? */ | |
5523 | if ((u16) (header_size + stack_size) < header_size) { | |
5524 | /* | |
5525 | * If we overflow the maximum size for the sample, | |
5526 | * we customize the stack dump size to fit in. | |
5527 | */ | |
5528 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5529 | stack_size = round_up(stack_size, sizeof(u64)); | |
5530 | } | |
5531 | ||
5532 | return stack_size; | |
5533 | } | |
5534 | ||
5535 | static void | |
5536 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5537 | struct pt_regs *regs) | |
5538 | { | |
5539 | /* Case of a kernel thread, nothing to dump */ | |
5540 | if (!regs) { | |
5541 | u64 size = 0; | |
5542 | perf_output_put(handle, size); | |
5543 | } else { | |
5544 | unsigned long sp; | |
5545 | unsigned int rem; | |
5546 | u64 dyn_size; | |
5547 | ||
5548 | /* | |
5549 | * We dump: | |
5550 | * static size | |
5551 | * - the size requested by user or the best one we can fit | |
5552 | * in to the sample max size | |
5553 | * data | |
5554 | * - user stack dump data | |
5555 | * dynamic size | |
5556 | * - the actual dumped size | |
5557 | */ | |
5558 | ||
5559 | /* Static size. */ | |
5560 | perf_output_put(handle, dump_size); | |
5561 | ||
5562 | /* Data. */ | |
5563 | sp = perf_user_stack_pointer(regs); | |
5564 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5565 | dyn_size = dump_size - rem; | |
5566 | ||
5567 | perf_output_skip(handle, rem); | |
5568 | ||
5569 | /* Dynamic size. */ | |
5570 | perf_output_put(handle, dyn_size); | |
5571 | } | |
5572 | } | |
5573 | ||
c980d109 ACM |
5574 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5575 | struct perf_sample_data *data, | |
5576 | struct perf_event *event) | |
6844c09d ACM |
5577 | { |
5578 | u64 sample_type = event->attr.sample_type; | |
5579 | ||
5580 | data->type = sample_type; | |
5581 | header->size += event->id_header_size; | |
5582 | ||
5583 | if (sample_type & PERF_SAMPLE_TID) { | |
5584 | /* namespace issues */ | |
5585 | data->tid_entry.pid = perf_event_pid(event, current); | |
5586 | data->tid_entry.tid = perf_event_tid(event, current); | |
5587 | } | |
5588 | ||
5589 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5590 | data->time = perf_event_clock(event); |
6844c09d | 5591 | |
ff3d527c | 5592 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5593 | data->id = primary_event_id(event); |
5594 | ||
5595 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5596 | data->stream_id = event->id; | |
5597 | ||
5598 | if (sample_type & PERF_SAMPLE_CPU) { | |
5599 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5600 | data->cpu_entry.reserved = 0; | |
5601 | } | |
5602 | } | |
5603 | ||
76369139 FW |
5604 | void perf_event_header__init_id(struct perf_event_header *header, |
5605 | struct perf_sample_data *data, | |
5606 | struct perf_event *event) | |
c980d109 ACM |
5607 | { |
5608 | if (event->attr.sample_id_all) | |
5609 | __perf_event_header__init_id(header, data, event); | |
5610 | } | |
5611 | ||
5612 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5613 | struct perf_sample_data *data) | |
5614 | { | |
5615 | u64 sample_type = data->type; | |
5616 | ||
5617 | if (sample_type & PERF_SAMPLE_TID) | |
5618 | perf_output_put(handle, data->tid_entry); | |
5619 | ||
5620 | if (sample_type & PERF_SAMPLE_TIME) | |
5621 | perf_output_put(handle, data->time); | |
5622 | ||
5623 | if (sample_type & PERF_SAMPLE_ID) | |
5624 | perf_output_put(handle, data->id); | |
5625 | ||
5626 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5627 | perf_output_put(handle, data->stream_id); | |
5628 | ||
5629 | if (sample_type & PERF_SAMPLE_CPU) | |
5630 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5631 | |
5632 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5633 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5634 | } |
5635 | ||
76369139 FW |
5636 | void perf_event__output_id_sample(struct perf_event *event, |
5637 | struct perf_output_handle *handle, | |
5638 | struct perf_sample_data *sample) | |
c980d109 ACM |
5639 | { |
5640 | if (event->attr.sample_id_all) | |
5641 | __perf_event__output_id_sample(handle, sample); | |
5642 | } | |
5643 | ||
3dab77fb | 5644 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5645 | struct perf_event *event, |
5646 | u64 enabled, u64 running) | |
3dab77fb | 5647 | { |
cdd6c482 | 5648 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5649 | u64 values[4]; |
5650 | int n = 0; | |
5651 | ||
b5e58793 | 5652 | values[n++] = perf_event_count(event); |
3dab77fb | 5653 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5654 | values[n++] = enabled + |
cdd6c482 | 5655 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5656 | } |
5657 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5658 | values[n++] = running + |
cdd6c482 | 5659 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5660 | } |
5661 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5662 | values[n++] = primary_event_id(event); |
3dab77fb | 5663 | |
76369139 | 5664 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5665 | } |
5666 | ||
5667 | /* | |
cdd6c482 | 5668 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5669 | */ |
5670 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5671 | struct perf_event *event, |
5672 | u64 enabled, u64 running) | |
3dab77fb | 5673 | { |
cdd6c482 IM |
5674 | struct perf_event *leader = event->group_leader, *sub; |
5675 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5676 | u64 values[5]; |
5677 | int n = 0; | |
5678 | ||
5679 | values[n++] = 1 + leader->nr_siblings; | |
5680 | ||
5681 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5682 | values[n++] = enabled; |
3dab77fb PZ |
5683 | |
5684 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5685 | values[n++] = running; |
3dab77fb | 5686 | |
cdd6c482 | 5687 | if (leader != event) |
3dab77fb PZ |
5688 | leader->pmu->read(leader); |
5689 | ||
b5e58793 | 5690 | values[n++] = perf_event_count(leader); |
3dab77fb | 5691 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5692 | values[n++] = primary_event_id(leader); |
3dab77fb | 5693 | |
76369139 | 5694 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5695 | |
65abc865 | 5696 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5697 | n = 0; |
5698 | ||
6f5ab001 JO |
5699 | if ((sub != event) && |
5700 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5701 | sub->pmu->read(sub); |
5702 | ||
b5e58793 | 5703 | values[n++] = perf_event_count(sub); |
3dab77fb | 5704 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5705 | values[n++] = primary_event_id(sub); |
3dab77fb | 5706 | |
76369139 | 5707 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5708 | } |
5709 | } | |
5710 | ||
eed01528 SE |
5711 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5712 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5713 | ||
3dab77fb | 5714 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5715 | struct perf_event *event) |
3dab77fb | 5716 | { |
e3f3541c | 5717 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5718 | u64 read_format = event->attr.read_format; |
5719 | ||
5720 | /* | |
5721 | * compute total_time_enabled, total_time_running | |
5722 | * based on snapshot values taken when the event | |
5723 | * was last scheduled in. | |
5724 | * | |
5725 | * we cannot simply called update_context_time() | |
5726 | * because of locking issue as we are called in | |
5727 | * NMI context | |
5728 | */ | |
c4794295 | 5729 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5730 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5731 | |
cdd6c482 | 5732 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5733 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5734 | else |
eed01528 | 5735 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5736 | } |
5737 | ||
5622f295 MM |
5738 | void perf_output_sample(struct perf_output_handle *handle, |
5739 | struct perf_event_header *header, | |
5740 | struct perf_sample_data *data, | |
cdd6c482 | 5741 | struct perf_event *event) |
5622f295 MM |
5742 | { |
5743 | u64 sample_type = data->type; | |
5744 | ||
5745 | perf_output_put(handle, *header); | |
5746 | ||
ff3d527c AH |
5747 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5748 | perf_output_put(handle, data->id); | |
5749 | ||
5622f295 MM |
5750 | if (sample_type & PERF_SAMPLE_IP) |
5751 | perf_output_put(handle, data->ip); | |
5752 | ||
5753 | if (sample_type & PERF_SAMPLE_TID) | |
5754 | perf_output_put(handle, data->tid_entry); | |
5755 | ||
5756 | if (sample_type & PERF_SAMPLE_TIME) | |
5757 | perf_output_put(handle, data->time); | |
5758 | ||
5759 | if (sample_type & PERF_SAMPLE_ADDR) | |
5760 | perf_output_put(handle, data->addr); | |
5761 | ||
5762 | if (sample_type & PERF_SAMPLE_ID) | |
5763 | perf_output_put(handle, data->id); | |
5764 | ||
5765 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5766 | perf_output_put(handle, data->stream_id); | |
5767 | ||
5768 | if (sample_type & PERF_SAMPLE_CPU) | |
5769 | perf_output_put(handle, data->cpu_entry); | |
5770 | ||
5771 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5772 | perf_output_put(handle, data->period); | |
5773 | ||
5774 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5775 | perf_output_read(handle, event); |
5622f295 MM |
5776 | |
5777 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5778 | if (data->callchain) { | |
5779 | int size = 1; | |
5780 | ||
5781 | if (data->callchain) | |
5782 | size += data->callchain->nr; | |
5783 | ||
5784 | size *= sizeof(u64); | |
5785 | ||
76369139 | 5786 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5787 | } else { |
5788 | u64 nr = 0; | |
5789 | perf_output_put(handle, nr); | |
5790 | } | |
5791 | } | |
5792 | ||
5793 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5794 | struct perf_raw_record *raw = data->raw; |
5795 | ||
5796 | if (raw) { | |
5797 | struct perf_raw_frag *frag = &raw->frag; | |
5798 | ||
5799 | perf_output_put(handle, raw->size); | |
5800 | do { | |
5801 | if (frag->copy) { | |
5802 | __output_custom(handle, frag->copy, | |
5803 | frag->data, frag->size); | |
5804 | } else { | |
5805 | __output_copy(handle, frag->data, | |
5806 | frag->size); | |
5807 | } | |
5808 | if (perf_raw_frag_last(frag)) | |
5809 | break; | |
5810 | frag = frag->next; | |
5811 | } while (1); | |
5812 | if (frag->pad) | |
5813 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5814 | } else { |
5815 | struct { | |
5816 | u32 size; | |
5817 | u32 data; | |
5818 | } raw = { | |
5819 | .size = sizeof(u32), | |
5820 | .data = 0, | |
5821 | }; | |
5822 | perf_output_put(handle, raw); | |
5823 | } | |
5824 | } | |
a7ac67ea | 5825 | |
bce38cd5 SE |
5826 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5827 | if (data->br_stack) { | |
5828 | size_t size; | |
5829 | ||
5830 | size = data->br_stack->nr | |
5831 | * sizeof(struct perf_branch_entry); | |
5832 | ||
5833 | perf_output_put(handle, data->br_stack->nr); | |
5834 | perf_output_copy(handle, data->br_stack->entries, size); | |
5835 | } else { | |
5836 | /* | |
5837 | * we always store at least the value of nr | |
5838 | */ | |
5839 | u64 nr = 0; | |
5840 | perf_output_put(handle, nr); | |
5841 | } | |
5842 | } | |
4018994f JO |
5843 | |
5844 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5845 | u64 abi = data->regs_user.abi; | |
5846 | ||
5847 | /* | |
5848 | * If there are no regs to dump, notice it through | |
5849 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5850 | */ | |
5851 | perf_output_put(handle, abi); | |
5852 | ||
5853 | if (abi) { | |
5854 | u64 mask = event->attr.sample_regs_user; | |
5855 | perf_output_sample_regs(handle, | |
5856 | data->regs_user.regs, | |
5857 | mask); | |
5858 | } | |
5859 | } | |
c5ebcedb | 5860 | |
a5cdd40c | 5861 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5862 | perf_output_sample_ustack(handle, |
5863 | data->stack_user_size, | |
5864 | data->regs_user.regs); | |
a5cdd40c | 5865 | } |
c3feedf2 AK |
5866 | |
5867 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5868 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5869 | |
5870 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5871 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5872 | |
fdfbbd07 AK |
5873 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5874 | perf_output_put(handle, data->txn); | |
5875 | ||
60e2364e SE |
5876 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5877 | u64 abi = data->regs_intr.abi; | |
5878 | /* | |
5879 | * If there are no regs to dump, notice it through | |
5880 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5881 | */ | |
5882 | perf_output_put(handle, abi); | |
5883 | ||
5884 | if (abi) { | |
5885 | u64 mask = event->attr.sample_regs_intr; | |
5886 | ||
5887 | perf_output_sample_regs(handle, | |
5888 | data->regs_intr.regs, | |
5889 | mask); | |
5890 | } | |
5891 | } | |
5892 | ||
a5cdd40c PZ |
5893 | if (!event->attr.watermark) { |
5894 | int wakeup_events = event->attr.wakeup_events; | |
5895 | ||
5896 | if (wakeup_events) { | |
5897 | struct ring_buffer *rb = handle->rb; | |
5898 | int events = local_inc_return(&rb->events); | |
5899 | ||
5900 | if (events >= wakeup_events) { | |
5901 | local_sub(wakeup_events, &rb->events); | |
5902 | local_inc(&rb->wakeup); | |
5903 | } | |
5904 | } | |
5905 | } | |
5622f295 MM |
5906 | } |
5907 | ||
5908 | void perf_prepare_sample(struct perf_event_header *header, | |
5909 | struct perf_sample_data *data, | |
cdd6c482 | 5910 | struct perf_event *event, |
5622f295 | 5911 | struct pt_regs *regs) |
7b732a75 | 5912 | { |
cdd6c482 | 5913 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5914 | |
cdd6c482 | 5915 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5916 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5917 | |
5918 | header->misc = 0; | |
5919 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5920 | |
c980d109 | 5921 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5922 | |
c320c7b7 | 5923 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5924 | data->ip = perf_instruction_pointer(regs); |
5925 | ||
b23f3325 | 5926 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5927 | int size = 1; |
394ee076 | 5928 | |
e6dab5ff | 5929 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5930 | |
5931 | if (data->callchain) | |
5932 | size += data->callchain->nr; | |
5933 | ||
5934 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5935 | } |
5936 | ||
3a43ce68 | 5937 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
5938 | struct perf_raw_record *raw = data->raw; |
5939 | int size; | |
5940 | ||
5941 | if (raw) { | |
5942 | struct perf_raw_frag *frag = &raw->frag; | |
5943 | u32 sum = 0; | |
5944 | ||
5945 | do { | |
5946 | sum += frag->size; | |
5947 | if (perf_raw_frag_last(frag)) | |
5948 | break; | |
5949 | frag = frag->next; | |
5950 | } while (1); | |
5951 | ||
5952 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
5953 | raw->size = size - sizeof(u32); | |
5954 | frag->pad = raw->size - sum; | |
5955 | } else { | |
5956 | size = sizeof(u64); | |
5957 | } | |
a044560c | 5958 | |
7e3f977e | 5959 | header->size += size; |
7f453c24 | 5960 | } |
bce38cd5 SE |
5961 | |
5962 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5963 | int size = sizeof(u64); /* nr */ | |
5964 | if (data->br_stack) { | |
5965 | size += data->br_stack->nr | |
5966 | * sizeof(struct perf_branch_entry); | |
5967 | } | |
5968 | header->size += size; | |
5969 | } | |
4018994f | 5970 | |
2565711f | 5971 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5972 | perf_sample_regs_user(&data->regs_user, regs, |
5973 | &data->regs_user_copy); | |
2565711f | 5974 | |
4018994f JO |
5975 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5976 | /* regs dump ABI info */ | |
5977 | int size = sizeof(u64); | |
5978 | ||
4018994f JO |
5979 | if (data->regs_user.regs) { |
5980 | u64 mask = event->attr.sample_regs_user; | |
5981 | size += hweight64(mask) * sizeof(u64); | |
5982 | } | |
5983 | ||
5984 | header->size += size; | |
5985 | } | |
c5ebcedb JO |
5986 | |
5987 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5988 | /* | |
5989 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5990 | * processed as the last one or have additional check added | |
5991 | * in case new sample type is added, because we could eat | |
5992 | * up the rest of the sample size. | |
5993 | */ | |
c5ebcedb JO |
5994 | u16 stack_size = event->attr.sample_stack_user; |
5995 | u16 size = sizeof(u64); | |
5996 | ||
c5ebcedb | 5997 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5998 | data->regs_user.regs); |
c5ebcedb JO |
5999 | |
6000 | /* | |
6001 | * If there is something to dump, add space for the dump | |
6002 | * itself and for the field that tells the dynamic size, | |
6003 | * which is how many have been actually dumped. | |
6004 | */ | |
6005 | if (stack_size) | |
6006 | size += sizeof(u64) + stack_size; | |
6007 | ||
6008 | data->stack_user_size = stack_size; | |
6009 | header->size += size; | |
6010 | } | |
60e2364e SE |
6011 | |
6012 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6013 | /* regs dump ABI info */ | |
6014 | int size = sizeof(u64); | |
6015 | ||
6016 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6017 | ||
6018 | if (data->regs_intr.regs) { | |
6019 | u64 mask = event->attr.sample_regs_intr; | |
6020 | ||
6021 | size += hweight64(mask) * sizeof(u64); | |
6022 | } | |
6023 | ||
6024 | header->size += size; | |
6025 | } | |
5622f295 | 6026 | } |
7f453c24 | 6027 | |
9ecda41a WN |
6028 | static void __always_inline |
6029 | __perf_event_output(struct perf_event *event, | |
6030 | struct perf_sample_data *data, | |
6031 | struct pt_regs *regs, | |
6032 | int (*output_begin)(struct perf_output_handle *, | |
6033 | struct perf_event *, | |
6034 | unsigned int)) | |
5622f295 MM |
6035 | { |
6036 | struct perf_output_handle handle; | |
6037 | struct perf_event_header header; | |
689802b2 | 6038 | |
927c7a9e FW |
6039 | /* protect the callchain buffers */ |
6040 | rcu_read_lock(); | |
6041 | ||
cdd6c482 | 6042 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6043 | |
9ecda41a | 6044 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6045 | goto exit; |
0322cd6e | 6046 | |
cdd6c482 | 6047 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6048 | |
8a057d84 | 6049 | perf_output_end(&handle); |
927c7a9e FW |
6050 | |
6051 | exit: | |
6052 | rcu_read_unlock(); | |
0322cd6e PZ |
6053 | } |
6054 | ||
9ecda41a WN |
6055 | void |
6056 | perf_event_output_forward(struct perf_event *event, | |
6057 | struct perf_sample_data *data, | |
6058 | struct pt_regs *regs) | |
6059 | { | |
6060 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6061 | } | |
6062 | ||
6063 | void | |
6064 | perf_event_output_backward(struct perf_event *event, | |
6065 | struct perf_sample_data *data, | |
6066 | struct pt_regs *regs) | |
6067 | { | |
6068 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6069 | } | |
6070 | ||
6071 | void | |
6072 | perf_event_output(struct perf_event *event, | |
6073 | struct perf_sample_data *data, | |
6074 | struct pt_regs *regs) | |
6075 | { | |
6076 | __perf_event_output(event, data, regs, perf_output_begin); | |
6077 | } | |
6078 | ||
38b200d6 | 6079 | /* |
cdd6c482 | 6080 | * read event_id |
38b200d6 PZ |
6081 | */ |
6082 | ||
6083 | struct perf_read_event { | |
6084 | struct perf_event_header header; | |
6085 | ||
6086 | u32 pid; | |
6087 | u32 tid; | |
38b200d6 PZ |
6088 | }; |
6089 | ||
6090 | static void | |
cdd6c482 | 6091 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6092 | struct task_struct *task) |
6093 | { | |
6094 | struct perf_output_handle handle; | |
c980d109 | 6095 | struct perf_sample_data sample; |
dfc65094 | 6096 | struct perf_read_event read_event = { |
38b200d6 | 6097 | .header = { |
cdd6c482 | 6098 | .type = PERF_RECORD_READ, |
38b200d6 | 6099 | .misc = 0, |
c320c7b7 | 6100 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6101 | }, |
cdd6c482 IM |
6102 | .pid = perf_event_pid(event, task), |
6103 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6104 | }; |
3dab77fb | 6105 | int ret; |
38b200d6 | 6106 | |
c980d109 | 6107 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6108 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6109 | if (ret) |
6110 | return; | |
6111 | ||
dfc65094 | 6112 | perf_output_put(&handle, read_event); |
cdd6c482 | 6113 | perf_output_read(&handle, event); |
c980d109 | 6114 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6115 | |
38b200d6 PZ |
6116 | perf_output_end(&handle); |
6117 | } | |
6118 | ||
aab5b71e | 6119 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6120 | |
6121 | static void | |
aab5b71e PZ |
6122 | perf_iterate_ctx(struct perf_event_context *ctx, |
6123 | perf_iterate_f output, | |
b73e4fef | 6124 | void *data, bool all) |
52d857a8 JO |
6125 | { |
6126 | struct perf_event *event; | |
6127 | ||
6128 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6129 | if (!all) { |
6130 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6131 | continue; | |
6132 | if (!event_filter_match(event)) | |
6133 | continue; | |
6134 | } | |
6135 | ||
67516844 | 6136 | output(event, data); |
52d857a8 JO |
6137 | } |
6138 | } | |
6139 | ||
aab5b71e | 6140 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6141 | { |
6142 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6143 | struct perf_event *event; | |
6144 | ||
6145 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6146 | /* |
6147 | * Skip events that are not fully formed yet; ensure that | |
6148 | * if we observe event->ctx, both event and ctx will be | |
6149 | * complete enough. See perf_install_in_context(). | |
6150 | */ | |
6151 | if (!smp_load_acquire(&event->ctx)) | |
6152 | continue; | |
6153 | ||
f2fb6bef KL |
6154 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6155 | continue; | |
6156 | if (!event_filter_match(event)) | |
6157 | continue; | |
6158 | output(event, data); | |
6159 | } | |
6160 | } | |
6161 | ||
aab5b71e PZ |
6162 | /* |
6163 | * Iterate all events that need to receive side-band events. | |
6164 | * | |
6165 | * For new callers; ensure that account_pmu_sb_event() includes | |
6166 | * your event, otherwise it might not get delivered. | |
6167 | */ | |
52d857a8 | 6168 | static void |
aab5b71e | 6169 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6170 | struct perf_event_context *task_ctx) |
6171 | { | |
52d857a8 | 6172 | struct perf_event_context *ctx; |
52d857a8 JO |
6173 | int ctxn; |
6174 | ||
aab5b71e PZ |
6175 | rcu_read_lock(); |
6176 | preempt_disable(); | |
6177 | ||
4e93ad60 | 6178 | /* |
aab5b71e PZ |
6179 | * If we have task_ctx != NULL we only notify the task context itself. |
6180 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6181 | * context. |
6182 | */ | |
6183 | if (task_ctx) { | |
aab5b71e PZ |
6184 | perf_iterate_ctx(task_ctx, output, data, false); |
6185 | goto done; | |
4e93ad60 JO |
6186 | } |
6187 | ||
aab5b71e | 6188 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6189 | |
6190 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6191 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6192 | if (ctx) | |
aab5b71e | 6193 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6194 | } |
aab5b71e | 6195 | done: |
f2fb6bef | 6196 | preempt_enable(); |
52d857a8 | 6197 | rcu_read_unlock(); |
95ff4ca2 AS |
6198 | } |
6199 | ||
375637bc AS |
6200 | /* |
6201 | * Clear all file-based filters at exec, they'll have to be | |
6202 | * re-instated when/if these objects are mmapped again. | |
6203 | */ | |
6204 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6205 | { | |
6206 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6207 | struct perf_addr_filter *filter; | |
6208 | unsigned int restart = 0, count = 0; | |
6209 | unsigned long flags; | |
6210 | ||
6211 | if (!has_addr_filter(event)) | |
6212 | return; | |
6213 | ||
6214 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6215 | list_for_each_entry(filter, &ifh->list, entry) { | |
6216 | if (filter->inode) { | |
6217 | event->addr_filters_offs[count] = 0; | |
6218 | restart++; | |
6219 | } | |
6220 | ||
6221 | count++; | |
6222 | } | |
6223 | ||
6224 | if (restart) | |
6225 | event->addr_filters_gen++; | |
6226 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6227 | ||
6228 | if (restart) | |
767ae086 | 6229 | perf_event_stop(event, 1); |
375637bc AS |
6230 | } |
6231 | ||
6232 | void perf_event_exec(void) | |
6233 | { | |
6234 | struct perf_event_context *ctx; | |
6235 | int ctxn; | |
6236 | ||
6237 | rcu_read_lock(); | |
6238 | for_each_task_context_nr(ctxn) { | |
6239 | ctx = current->perf_event_ctxp[ctxn]; | |
6240 | if (!ctx) | |
6241 | continue; | |
6242 | ||
6243 | perf_event_enable_on_exec(ctxn); | |
6244 | ||
aab5b71e | 6245 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6246 | true); |
6247 | } | |
6248 | rcu_read_unlock(); | |
6249 | } | |
6250 | ||
95ff4ca2 AS |
6251 | struct remote_output { |
6252 | struct ring_buffer *rb; | |
6253 | int err; | |
6254 | }; | |
6255 | ||
6256 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6257 | { | |
6258 | struct perf_event *parent = event->parent; | |
6259 | struct remote_output *ro = data; | |
6260 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6261 | struct stop_event_data sd = { |
6262 | .event = event, | |
6263 | }; | |
95ff4ca2 AS |
6264 | |
6265 | if (!has_aux(event)) | |
6266 | return; | |
6267 | ||
6268 | if (!parent) | |
6269 | parent = event; | |
6270 | ||
6271 | /* | |
6272 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6273 | * ring-buffer, but it will be the child that's actually using it. |
6274 | * | |
6275 | * We are using event::rb to determine if the event should be stopped, | |
6276 | * however this may race with ring_buffer_attach() (through set_output), | |
6277 | * which will make us skip the event that actually needs to be stopped. | |
6278 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6279 | * its rb pointer. | |
95ff4ca2 AS |
6280 | */ |
6281 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6282 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6283 | } |
6284 | ||
6285 | static int __perf_pmu_output_stop(void *info) | |
6286 | { | |
6287 | struct perf_event *event = info; | |
6288 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6289 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6290 | struct remote_output ro = { |
6291 | .rb = event->rb, | |
6292 | }; | |
6293 | ||
6294 | rcu_read_lock(); | |
aab5b71e | 6295 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6296 | if (cpuctx->task_ctx) |
aab5b71e | 6297 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6298 | &ro, false); |
95ff4ca2 AS |
6299 | rcu_read_unlock(); |
6300 | ||
6301 | return ro.err; | |
6302 | } | |
6303 | ||
6304 | static void perf_pmu_output_stop(struct perf_event *event) | |
6305 | { | |
6306 | struct perf_event *iter; | |
6307 | int err, cpu; | |
6308 | ||
6309 | restart: | |
6310 | rcu_read_lock(); | |
6311 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6312 | /* | |
6313 | * For per-CPU events, we need to make sure that neither they | |
6314 | * nor their children are running; for cpu==-1 events it's | |
6315 | * sufficient to stop the event itself if it's active, since | |
6316 | * it can't have children. | |
6317 | */ | |
6318 | cpu = iter->cpu; | |
6319 | if (cpu == -1) | |
6320 | cpu = READ_ONCE(iter->oncpu); | |
6321 | ||
6322 | if (cpu == -1) | |
6323 | continue; | |
6324 | ||
6325 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6326 | if (err == -EAGAIN) { | |
6327 | rcu_read_unlock(); | |
6328 | goto restart; | |
6329 | } | |
6330 | } | |
6331 | rcu_read_unlock(); | |
52d857a8 JO |
6332 | } |
6333 | ||
60313ebe | 6334 | /* |
9f498cc5 PZ |
6335 | * task tracking -- fork/exit |
6336 | * | |
13d7a241 | 6337 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6338 | */ |
6339 | ||
9f498cc5 | 6340 | struct perf_task_event { |
3a80b4a3 | 6341 | struct task_struct *task; |
cdd6c482 | 6342 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6343 | |
6344 | struct { | |
6345 | struct perf_event_header header; | |
6346 | ||
6347 | u32 pid; | |
6348 | u32 ppid; | |
9f498cc5 PZ |
6349 | u32 tid; |
6350 | u32 ptid; | |
393b2ad8 | 6351 | u64 time; |
cdd6c482 | 6352 | } event_id; |
60313ebe PZ |
6353 | }; |
6354 | ||
67516844 JO |
6355 | static int perf_event_task_match(struct perf_event *event) |
6356 | { | |
13d7a241 SE |
6357 | return event->attr.comm || event->attr.mmap || |
6358 | event->attr.mmap2 || event->attr.mmap_data || | |
6359 | event->attr.task; | |
67516844 JO |
6360 | } |
6361 | ||
cdd6c482 | 6362 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6363 | void *data) |
60313ebe | 6364 | { |
52d857a8 | 6365 | struct perf_task_event *task_event = data; |
60313ebe | 6366 | struct perf_output_handle handle; |
c980d109 | 6367 | struct perf_sample_data sample; |
9f498cc5 | 6368 | struct task_struct *task = task_event->task; |
c980d109 | 6369 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6370 | |
67516844 JO |
6371 | if (!perf_event_task_match(event)) |
6372 | return; | |
6373 | ||
c980d109 | 6374 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6375 | |
c980d109 | 6376 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6377 | task_event->event_id.header.size); |
ef60777c | 6378 | if (ret) |
c980d109 | 6379 | goto out; |
60313ebe | 6380 | |
cdd6c482 IM |
6381 | task_event->event_id.pid = perf_event_pid(event, task); |
6382 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6383 | |
cdd6c482 IM |
6384 | task_event->event_id.tid = perf_event_tid(event, task); |
6385 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6386 | |
34f43927 PZ |
6387 | task_event->event_id.time = perf_event_clock(event); |
6388 | ||
cdd6c482 | 6389 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6390 | |
c980d109 ACM |
6391 | perf_event__output_id_sample(event, &handle, &sample); |
6392 | ||
60313ebe | 6393 | perf_output_end(&handle); |
c980d109 ACM |
6394 | out: |
6395 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6396 | } |
6397 | ||
cdd6c482 IM |
6398 | static void perf_event_task(struct task_struct *task, |
6399 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6400 | int new) |
60313ebe | 6401 | { |
9f498cc5 | 6402 | struct perf_task_event task_event; |
60313ebe | 6403 | |
cdd6c482 IM |
6404 | if (!atomic_read(&nr_comm_events) && |
6405 | !atomic_read(&nr_mmap_events) && | |
6406 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6407 | return; |
6408 | ||
9f498cc5 | 6409 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6410 | .task = task, |
6411 | .task_ctx = task_ctx, | |
cdd6c482 | 6412 | .event_id = { |
60313ebe | 6413 | .header = { |
cdd6c482 | 6414 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6415 | .misc = 0, |
cdd6c482 | 6416 | .size = sizeof(task_event.event_id), |
60313ebe | 6417 | }, |
573402db PZ |
6418 | /* .pid */ |
6419 | /* .ppid */ | |
9f498cc5 PZ |
6420 | /* .tid */ |
6421 | /* .ptid */ | |
34f43927 | 6422 | /* .time */ |
60313ebe PZ |
6423 | }, |
6424 | }; | |
6425 | ||
aab5b71e | 6426 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6427 | &task_event, |
6428 | task_ctx); | |
9f498cc5 PZ |
6429 | } |
6430 | ||
cdd6c482 | 6431 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6432 | { |
cdd6c482 | 6433 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
6434 | } |
6435 | ||
8d1b2d93 PZ |
6436 | /* |
6437 | * comm tracking | |
6438 | */ | |
6439 | ||
6440 | struct perf_comm_event { | |
22a4f650 IM |
6441 | struct task_struct *task; |
6442 | char *comm; | |
8d1b2d93 PZ |
6443 | int comm_size; |
6444 | ||
6445 | struct { | |
6446 | struct perf_event_header header; | |
6447 | ||
6448 | u32 pid; | |
6449 | u32 tid; | |
cdd6c482 | 6450 | } event_id; |
8d1b2d93 PZ |
6451 | }; |
6452 | ||
67516844 JO |
6453 | static int perf_event_comm_match(struct perf_event *event) |
6454 | { | |
6455 | return event->attr.comm; | |
6456 | } | |
6457 | ||
cdd6c482 | 6458 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6459 | void *data) |
8d1b2d93 | 6460 | { |
52d857a8 | 6461 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6462 | struct perf_output_handle handle; |
c980d109 | 6463 | struct perf_sample_data sample; |
cdd6c482 | 6464 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6465 | int ret; |
6466 | ||
67516844 JO |
6467 | if (!perf_event_comm_match(event)) |
6468 | return; | |
6469 | ||
c980d109 ACM |
6470 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6471 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6472 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6473 | |
6474 | if (ret) | |
c980d109 | 6475 | goto out; |
8d1b2d93 | 6476 | |
cdd6c482 IM |
6477 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6478 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6479 | |
cdd6c482 | 6480 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6481 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6482 | comm_event->comm_size); |
c980d109 ACM |
6483 | |
6484 | perf_event__output_id_sample(event, &handle, &sample); | |
6485 | ||
8d1b2d93 | 6486 | perf_output_end(&handle); |
c980d109 ACM |
6487 | out: |
6488 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6489 | } |
6490 | ||
cdd6c482 | 6491 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6492 | { |
413ee3b4 | 6493 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6494 | unsigned int size; |
8d1b2d93 | 6495 | |
413ee3b4 | 6496 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6497 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6498 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6499 | |
6500 | comm_event->comm = comm; | |
6501 | comm_event->comm_size = size; | |
6502 | ||
cdd6c482 | 6503 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6504 | |
aab5b71e | 6505 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6506 | comm_event, |
6507 | NULL); | |
8d1b2d93 PZ |
6508 | } |
6509 | ||
82b89778 | 6510 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6511 | { |
9ee318a7 PZ |
6512 | struct perf_comm_event comm_event; |
6513 | ||
cdd6c482 | 6514 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6515 | return; |
a63eaf34 | 6516 | |
9ee318a7 | 6517 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6518 | .task = task, |
573402db PZ |
6519 | /* .comm */ |
6520 | /* .comm_size */ | |
cdd6c482 | 6521 | .event_id = { |
573402db | 6522 | .header = { |
cdd6c482 | 6523 | .type = PERF_RECORD_COMM, |
82b89778 | 6524 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6525 | /* .size */ |
6526 | }, | |
6527 | /* .pid */ | |
6528 | /* .tid */ | |
8d1b2d93 PZ |
6529 | }, |
6530 | }; | |
6531 | ||
cdd6c482 | 6532 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6533 | } |
6534 | ||
0a4a9391 PZ |
6535 | /* |
6536 | * mmap tracking | |
6537 | */ | |
6538 | ||
6539 | struct perf_mmap_event { | |
089dd79d PZ |
6540 | struct vm_area_struct *vma; |
6541 | ||
6542 | const char *file_name; | |
6543 | int file_size; | |
13d7a241 SE |
6544 | int maj, min; |
6545 | u64 ino; | |
6546 | u64 ino_generation; | |
f972eb63 | 6547 | u32 prot, flags; |
0a4a9391 PZ |
6548 | |
6549 | struct { | |
6550 | struct perf_event_header header; | |
6551 | ||
6552 | u32 pid; | |
6553 | u32 tid; | |
6554 | u64 start; | |
6555 | u64 len; | |
6556 | u64 pgoff; | |
cdd6c482 | 6557 | } event_id; |
0a4a9391 PZ |
6558 | }; |
6559 | ||
67516844 JO |
6560 | static int perf_event_mmap_match(struct perf_event *event, |
6561 | void *data) | |
6562 | { | |
6563 | struct perf_mmap_event *mmap_event = data; | |
6564 | struct vm_area_struct *vma = mmap_event->vma; | |
6565 | int executable = vma->vm_flags & VM_EXEC; | |
6566 | ||
6567 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6568 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6569 | } |
6570 | ||
cdd6c482 | 6571 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6572 | void *data) |
0a4a9391 | 6573 | { |
52d857a8 | 6574 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6575 | struct perf_output_handle handle; |
c980d109 | 6576 | struct perf_sample_data sample; |
cdd6c482 | 6577 | int size = mmap_event->event_id.header.size; |
c980d109 | 6578 | int ret; |
0a4a9391 | 6579 | |
67516844 JO |
6580 | if (!perf_event_mmap_match(event, data)) |
6581 | return; | |
6582 | ||
13d7a241 SE |
6583 | if (event->attr.mmap2) { |
6584 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6585 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6586 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6587 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6588 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6589 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6590 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6591 | } |
6592 | ||
c980d109 ACM |
6593 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6594 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6595 | mmap_event->event_id.header.size); |
0a4a9391 | 6596 | if (ret) |
c980d109 | 6597 | goto out; |
0a4a9391 | 6598 | |
cdd6c482 IM |
6599 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6600 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6601 | |
cdd6c482 | 6602 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6603 | |
6604 | if (event->attr.mmap2) { | |
6605 | perf_output_put(&handle, mmap_event->maj); | |
6606 | perf_output_put(&handle, mmap_event->min); | |
6607 | perf_output_put(&handle, mmap_event->ino); | |
6608 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6609 | perf_output_put(&handle, mmap_event->prot); |
6610 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6611 | } |
6612 | ||
76369139 | 6613 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6614 | mmap_event->file_size); |
c980d109 ACM |
6615 | |
6616 | perf_event__output_id_sample(event, &handle, &sample); | |
6617 | ||
78d613eb | 6618 | perf_output_end(&handle); |
c980d109 ACM |
6619 | out: |
6620 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6621 | } |
6622 | ||
cdd6c482 | 6623 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6624 | { |
089dd79d PZ |
6625 | struct vm_area_struct *vma = mmap_event->vma; |
6626 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6627 | int maj = 0, min = 0; |
6628 | u64 ino = 0, gen = 0; | |
f972eb63 | 6629 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6630 | unsigned int size; |
6631 | char tmp[16]; | |
6632 | char *buf = NULL; | |
2c42cfbf | 6633 | char *name; |
413ee3b4 | 6634 | |
0b3589be PZ |
6635 | if (vma->vm_flags & VM_READ) |
6636 | prot |= PROT_READ; | |
6637 | if (vma->vm_flags & VM_WRITE) | |
6638 | prot |= PROT_WRITE; | |
6639 | if (vma->vm_flags & VM_EXEC) | |
6640 | prot |= PROT_EXEC; | |
6641 | ||
6642 | if (vma->vm_flags & VM_MAYSHARE) | |
6643 | flags = MAP_SHARED; | |
6644 | else | |
6645 | flags = MAP_PRIVATE; | |
6646 | ||
6647 | if (vma->vm_flags & VM_DENYWRITE) | |
6648 | flags |= MAP_DENYWRITE; | |
6649 | if (vma->vm_flags & VM_MAYEXEC) | |
6650 | flags |= MAP_EXECUTABLE; | |
6651 | if (vma->vm_flags & VM_LOCKED) | |
6652 | flags |= MAP_LOCKED; | |
6653 | if (vma->vm_flags & VM_HUGETLB) | |
6654 | flags |= MAP_HUGETLB; | |
6655 | ||
0a4a9391 | 6656 | if (file) { |
13d7a241 SE |
6657 | struct inode *inode; |
6658 | dev_t dev; | |
3ea2f2b9 | 6659 | |
2c42cfbf | 6660 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6661 | if (!buf) { |
c7e548b4 ON |
6662 | name = "//enomem"; |
6663 | goto cpy_name; | |
0a4a9391 | 6664 | } |
413ee3b4 | 6665 | /* |
3ea2f2b9 | 6666 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6667 | * need to add enough zero bytes after the string to handle |
6668 | * the 64bit alignment we do later. | |
6669 | */ | |
9bf39ab2 | 6670 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6671 | if (IS_ERR(name)) { |
c7e548b4 ON |
6672 | name = "//toolong"; |
6673 | goto cpy_name; | |
0a4a9391 | 6674 | } |
13d7a241 SE |
6675 | inode = file_inode(vma->vm_file); |
6676 | dev = inode->i_sb->s_dev; | |
6677 | ino = inode->i_ino; | |
6678 | gen = inode->i_generation; | |
6679 | maj = MAJOR(dev); | |
6680 | min = MINOR(dev); | |
f972eb63 | 6681 | |
c7e548b4 | 6682 | goto got_name; |
0a4a9391 | 6683 | } else { |
fbe26abe JO |
6684 | if (vma->vm_ops && vma->vm_ops->name) { |
6685 | name = (char *) vma->vm_ops->name(vma); | |
6686 | if (name) | |
6687 | goto cpy_name; | |
6688 | } | |
6689 | ||
2c42cfbf | 6690 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6691 | if (name) |
6692 | goto cpy_name; | |
089dd79d | 6693 | |
32c5fb7e | 6694 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6695 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6696 | name = "[heap]"; |
6697 | goto cpy_name; | |
32c5fb7e ON |
6698 | } |
6699 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6700 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6701 | name = "[stack]"; |
6702 | goto cpy_name; | |
089dd79d PZ |
6703 | } |
6704 | ||
c7e548b4 ON |
6705 | name = "//anon"; |
6706 | goto cpy_name; | |
0a4a9391 PZ |
6707 | } |
6708 | ||
c7e548b4 ON |
6709 | cpy_name: |
6710 | strlcpy(tmp, name, sizeof(tmp)); | |
6711 | name = tmp; | |
0a4a9391 | 6712 | got_name: |
2c42cfbf PZ |
6713 | /* |
6714 | * Since our buffer works in 8 byte units we need to align our string | |
6715 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6716 | * zero'd out to avoid leaking random bits to userspace. | |
6717 | */ | |
6718 | size = strlen(name)+1; | |
6719 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6720 | name[size++] = '\0'; | |
0a4a9391 PZ |
6721 | |
6722 | mmap_event->file_name = name; | |
6723 | mmap_event->file_size = size; | |
13d7a241 SE |
6724 | mmap_event->maj = maj; |
6725 | mmap_event->min = min; | |
6726 | mmap_event->ino = ino; | |
6727 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6728 | mmap_event->prot = prot; |
6729 | mmap_event->flags = flags; | |
0a4a9391 | 6730 | |
2fe85427 SE |
6731 | if (!(vma->vm_flags & VM_EXEC)) |
6732 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6733 | ||
cdd6c482 | 6734 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6735 | |
aab5b71e | 6736 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6737 | mmap_event, |
6738 | NULL); | |
665c2142 | 6739 | |
0a4a9391 PZ |
6740 | kfree(buf); |
6741 | } | |
6742 | ||
375637bc AS |
6743 | /* |
6744 | * Check whether inode and address range match filter criteria. | |
6745 | */ | |
6746 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6747 | struct file *file, unsigned long offset, | |
6748 | unsigned long size) | |
6749 | { | |
45063097 | 6750 | if (filter->inode != file_inode(file)) |
375637bc AS |
6751 | return false; |
6752 | ||
6753 | if (filter->offset > offset + size) | |
6754 | return false; | |
6755 | ||
6756 | if (filter->offset + filter->size < offset) | |
6757 | return false; | |
6758 | ||
6759 | return true; | |
6760 | } | |
6761 | ||
6762 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6763 | { | |
6764 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6765 | struct vm_area_struct *vma = data; | |
6766 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6767 | struct file *file = vma->vm_file; | |
6768 | struct perf_addr_filter *filter; | |
6769 | unsigned int restart = 0, count = 0; | |
6770 | ||
6771 | if (!has_addr_filter(event)) | |
6772 | return; | |
6773 | ||
6774 | if (!file) | |
6775 | return; | |
6776 | ||
6777 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6778 | list_for_each_entry(filter, &ifh->list, entry) { | |
6779 | if (perf_addr_filter_match(filter, file, off, | |
6780 | vma->vm_end - vma->vm_start)) { | |
6781 | event->addr_filters_offs[count] = vma->vm_start; | |
6782 | restart++; | |
6783 | } | |
6784 | ||
6785 | count++; | |
6786 | } | |
6787 | ||
6788 | if (restart) | |
6789 | event->addr_filters_gen++; | |
6790 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6791 | ||
6792 | if (restart) | |
767ae086 | 6793 | perf_event_stop(event, 1); |
375637bc AS |
6794 | } |
6795 | ||
6796 | /* | |
6797 | * Adjust all task's events' filters to the new vma | |
6798 | */ | |
6799 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6800 | { | |
6801 | struct perf_event_context *ctx; | |
6802 | int ctxn; | |
6803 | ||
12b40a23 MP |
6804 | /* |
6805 | * Data tracing isn't supported yet and as such there is no need | |
6806 | * to keep track of anything that isn't related to executable code: | |
6807 | */ | |
6808 | if (!(vma->vm_flags & VM_EXEC)) | |
6809 | return; | |
6810 | ||
375637bc AS |
6811 | rcu_read_lock(); |
6812 | for_each_task_context_nr(ctxn) { | |
6813 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
6814 | if (!ctx) | |
6815 | continue; | |
6816 | ||
aab5b71e | 6817 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
6818 | } |
6819 | rcu_read_unlock(); | |
6820 | } | |
6821 | ||
3af9e859 | 6822 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6823 | { |
9ee318a7 PZ |
6824 | struct perf_mmap_event mmap_event; |
6825 | ||
cdd6c482 | 6826 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6827 | return; |
6828 | ||
6829 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6830 | .vma = vma, |
573402db PZ |
6831 | /* .file_name */ |
6832 | /* .file_size */ | |
cdd6c482 | 6833 | .event_id = { |
573402db | 6834 | .header = { |
cdd6c482 | 6835 | .type = PERF_RECORD_MMAP, |
39447b38 | 6836 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6837 | /* .size */ |
6838 | }, | |
6839 | /* .pid */ | |
6840 | /* .tid */ | |
089dd79d PZ |
6841 | .start = vma->vm_start, |
6842 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6843 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6844 | }, |
13d7a241 SE |
6845 | /* .maj (attr_mmap2 only) */ |
6846 | /* .min (attr_mmap2 only) */ | |
6847 | /* .ino (attr_mmap2 only) */ | |
6848 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6849 | /* .prot (attr_mmap2 only) */ |
6850 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6851 | }; |
6852 | ||
375637bc | 6853 | perf_addr_filters_adjust(vma); |
cdd6c482 | 6854 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6855 | } |
6856 | ||
68db7e98 AS |
6857 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6858 | unsigned long size, u64 flags) | |
6859 | { | |
6860 | struct perf_output_handle handle; | |
6861 | struct perf_sample_data sample; | |
6862 | struct perf_aux_event { | |
6863 | struct perf_event_header header; | |
6864 | u64 offset; | |
6865 | u64 size; | |
6866 | u64 flags; | |
6867 | } rec = { | |
6868 | .header = { | |
6869 | .type = PERF_RECORD_AUX, | |
6870 | .misc = 0, | |
6871 | .size = sizeof(rec), | |
6872 | }, | |
6873 | .offset = head, | |
6874 | .size = size, | |
6875 | .flags = flags, | |
6876 | }; | |
6877 | int ret; | |
6878 | ||
6879 | perf_event_header__init_id(&rec.header, &sample, event); | |
6880 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6881 | ||
6882 | if (ret) | |
6883 | return; | |
6884 | ||
6885 | perf_output_put(&handle, rec); | |
6886 | perf_event__output_id_sample(event, &handle, &sample); | |
6887 | ||
6888 | perf_output_end(&handle); | |
6889 | } | |
6890 | ||
f38b0dbb KL |
6891 | /* |
6892 | * Lost/dropped samples logging | |
6893 | */ | |
6894 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6895 | { | |
6896 | struct perf_output_handle handle; | |
6897 | struct perf_sample_data sample; | |
6898 | int ret; | |
6899 | ||
6900 | struct { | |
6901 | struct perf_event_header header; | |
6902 | u64 lost; | |
6903 | } lost_samples_event = { | |
6904 | .header = { | |
6905 | .type = PERF_RECORD_LOST_SAMPLES, | |
6906 | .misc = 0, | |
6907 | .size = sizeof(lost_samples_event), | |
6908 | }, | |
6909 | .lost = lost, | |
6910 | }; | |
6911 | ||
6912 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6913 | ||
6914 | ret = perf_output_begin(&handle, event, | |
6915 | lost_samples_event.header.size); | |
6916 | if (ret) | |
6917 | return; | |
6918 | ||
6919 | perf_output_put(&handle, lost_samples_event); | |
6920 | perf_event__output_id_sample(event, &handle, &sample); | |
6921 | perf_output_end(&handle); | |
6922 | } | |
6923 | ||
45ac1403 AH |
6924 | /* |
6925 | * context_switch tracking | |
6926 | */ | |
6927 | ||
6928 | struct perf_switch_event { | |
6929 | struct task_struct *task; | |
6930 | struct task_struct *next_prev; | |
6931 | ||
6932 | struct { | |
6933 | struct perf_event_header header; | |
6934 | u32 next_prev_pid; | |
6935 | u32 next_prev_tid; | |
6936 | } event_id; | |
6937 | }; | |
6938 | ||
6939 | static int perf_event_switch_match(struct perf_event *event) | |
6940 | { | |
6941 | return event->attr.context_switch; | |
6942 | } | |
6943 | ||
6944 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6945 | { | |
6946 | struct perf_switch_event *se = data; | |
6947 | struct perf_output_handle handle; | |
6948 | struct perf_sample_data sample; | |
6949 | int ret; | |
6950 | ||
6951 | if (!perf_event_switch_match(event)) | |
6952 | return; | |
6953 | ||
6954 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6955 | if (event->ctx->task) { | |
6956 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6957 | se->event_id.header.size = sizeof(se->event_id.header); | |
6958 | } else { | |
6959 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6960 | se->event_id.header.size = sizeof(se->event_id); | |
6961 | se->event_id.next_prev_pid = | |
6962 | perf_event_pid(event, se->next_prev); | |
6963 | se->event_id.next_prev_tid = | |
6964 | perf_event_tid(event, se->next_prev); | |
6965 | } | |
6966 | ||
6967 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6968 | ||
6969 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6970 | if (ret) | |
6971 | return; | |
6972 | ||
6973 | if (event->ctx->task) | |
6974 | perf_output_put(&handle, se->event_id.header); | |
6975 | else | |
6976 | perf_output_put(&handle, se->event_id); | |
6977 | ||
6978 | perf_event__output_id_sample(event, &handle, &sample); | |
6979 | ||
6980 | perf_output_end(&handle); | |
6981 | } | |
6982 | ||
6983 | static void perf_event_switch(struct task_struct *task, | |
6984 | struct task_struct *next_prev, bool sched_in) | |
6985 | { | |
6986 | struct perf_switch_event switch_event; | |
6987 | ||
6988 | /* N.B. caller checks nr_switch_events != 0 */ | |
6989 | ||
6990 | switch_event = (struct perf_switch_event){ | |
6991 | .task = task, | |
6992 | .next_prev = next_prev, | |
6993 | .event_id = { | |
6994 | .header = { | |
6995 | /* .type */ | |
6996 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6997 | /* .size */ | |
6998 | }, | |
6999 | /* .next_prev_pid */ | |
7000 | /* .next_prev_tid */ | |
7001 | }, | |
7002 | }; | |
7003 | ||
aab5b71e | 7004 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7005 | &switch_event, |
7006 | NULL); | |
7007 | } | |
7008 | ||
a78ac325 PZ |
7009 | /* |
7010 | * IRQ throttle logging | |
7011 | */ | |
7012 | ||
cdd6c482 | 7013 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7014 | { |
7015 | struct perf_output_handle handle; | |
c980d109 | 7016 | struct perf_sample_data sample; |
a78ac325 PZ |
7017 | int ret; |
7018 | ||
7019 | struct { | |
7020 | struct perf_event_header header; | |
7021 | u64 time; | |
cca3f454 | 7022 | u64 id; |
7f453c24 | 7023 | u64 stream_id; |
a78ac325 PZ |
7024 | } throttle_event = { |
7025 | .header = { | |
cdd6c482 | 7026 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7027 | .misc = 0, |
7028 | .size = sizeof(throttle_event), | |
7029 | }, | |
34f43927 | 7030 | .time = perf_event_clock(event), |
cdd6c482 IM |
7031 | .id = primary_event_id(event), |
7032 | .stream_id = event->id, | |
a78ac325 PZ |
7033 | }; |
7034 | ||
966ee4d6 | 7035 | if (enable) |
cdd6c482 | 7036 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7037 | |
c980d109 ACM |
7038 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7039 | ||
7040 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7041 | throttle_event.header.size); |
a78ac325 PZ |
7042 | if (ret) |
7043 | return; | |
7044 | ||
7045 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7046 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7047 | perf_output_end(&handle); |
7048 | } | |
7049 | ||
ec0d7729 AS |
7050 | static void perf_log_itrace_start(struct perf_event *event) |
7051 | { | |
7052 | struct perf_output_handle handle; | |
7053 | struct perf_sample_data sample; | |
7054 | struct perf_aux_event { | |
7055 | struct perf_event_header header; | |
7056 | u32 pid; | |
7057 | u32 tid; | |
7058 | } rec; | |
7059 | int ret; | |
7060 | ||
7061 | if (event->parent) | |
7062 | event = event->parent; | |
7063 | ||
7064 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
7065 | event->hw.itrace_started) | |
7066 | return; | |
7067 | ||
ec0d7729 AS |
7068 | rec.header.type = PERF_RECORD_ITRACE_START; |
7069 | rec.header.misc = 0; | |
7070 | rec.header.size = sizeof(rec); | |
7071 | rec.pid = perf_event_pid(event, current); | |
7072 | rec.tid = perf_event_tid(event, current); | |
7073 | ||
7074 | perf_event_header__init_id(&rec.header, &sample, event); | |
7075 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7076 | ||
7077 | if (ret) | |
7078 | return; | |
7079 | ||
7080 | perf_output_put(&handle, rec); | |
7081 | perf_event__output_id_sample(event, &handle, &sample); | |
7082 | ||
7083 | perf_output_end(&handle); | |
7084 | } | |
7085 | ||
475113d9 JO |
7086 | static int |
7087 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7088 | { |
cdd6c482 | 7089 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7090 | int ret = 0; |
475113d9 | 7091 | u64 seq; |
96398826 | 7092 | |
e050e3f0 SE |
7093 | seq = __this_cpu_read(perf_throttled_seq); |
7094 | if (seq != hwc->interrupts_seq) { | |
7095 | hwc->interrupts_seq = seq; | |
7096 | hwc->interrupts = 1; | |
7097 | } else { | |
7098 | hwc->interrupts++; | |
7099 | if (unlikely(throttle | |
7100 | && hwc->interrupts >= max_samples_per_tick)) { | |
7101 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7102 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7103 | hwc->interrupts = MAX_INTERRUPTS; |
7104 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7105 | ret = 1; |
7106 | } | |
e050e3f0 | 7107 | } |
60db5e09 | 7108 | |
cdd6c482 | 7109 | if (event->attr.freq) { |
def0a9b2 | 7110 | u64 now = perf_clock(); |
abd50713 | 7111 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7112 | |
abd50713 | 7113 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7114 | |
abd50713 | 7115 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7116 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7117 | } |
7118 | ||
475113d9 JO |
7119 | return ret; |
7120 | } | |
7121 | ||
7122 | int perf_event_account_interrupt(struct perf_event *event) | |
7123 | { | |
7124 | return __perf_event_account_interrupt(event, 1); | |
7125 | } | |
7126 | ||
7127 | /* | |
7128 | * Generic event overflow handling, sampling. | |
7129 | */ | |
7130 | ||
7131 | static int __perf_event_overflow(struct perf_event *event, | |
7132 | int throttle, struct perf_sample_data *data, | |
7133 | struct pt_regs *regs) | |
7134 | { | |
7135 | int events = atomic_read(&event->event_limit); | |
7136 | int ret = 0; | |
7137 | ||
7138 | /* | |
7139 | * Non-sampling counters might still use the PMI to fold short | |
7140 | * hardware counters, ignore those. | |
7141 | */ | |
7142 | if (unlikely(!is_sampling_event(event))) | |
7143 | return 0; | |
7144 | ||
7145 | ret = __perf_event_account_interrupt(event, throttle); | |
7146 | ||
2023b359 PZ |
7147 | /* |
7148 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7149 | * events |
2023b359 PZ |
7150 | */ |
7151 | ||
cdd6c482 IM |
7152 | event->pending_kill = POLL_IN; |
7153 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7154 | ret = 1; |
cdd6c482 | 7155 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7156 | |
7157 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7158 | } |
7159 | ||
aa6a5f3c | 7160 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7161 | |
fed66e2c | 7162 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7163 | event->pending_wakeup = 1; |
7164 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7165 | } |
7166 | ||
79f14641 | 7167 | return ret; |
f6c7d5fe PZ |
7168 | } |
7169 | ||
a8b0ca17 | 7170 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7171 | struct perf_sample_data *data, |
7172 | struct pt_regs *regs) | |
850bc73f | 7173 | { |
a8b0ca17 | 7174 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7175 | } |
7176 | ||
15dbf27c | 7177 | /* |
cdd6c482 | 7178 | * Generic software event infrastructure |
15dbf27c PZ |
7179 | */ |
7180 | ||
b28ab83c PZ |
7181 | struct swevent_htable { |
7182 | struct swevent_hlist *swevent_hlist; | |
7183 | struct mutex hlist_mutex; | |
7184 | int hlist_refcount; | |
7185 | ||
7186 | /* Recursion avoidance in each contexts */ | |
7187 | int recursion[PERF_NR_CONTEXTS]; | |
7188 | }; | |
7189 | ||
7190 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7191 | ||
7b4b6658 | 7192 | /* |
cdd6c482 IM |
7193 | * We directly increment event->count and keep a second value in |
7194 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7195 | * is kept in the range [-sample_period, 0] so that we can use the |
7196 | * sign as trigger. | |
7197 | */ | |
7198 | ||
ab573844 | 7199 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7200 | { |
cdd6c482 | 7201 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7202 | u64 period = hwc->last_period; |
7203 | u64 nr, offset; | |
7204 | s64 old, val; | |
7205 | ||
7206 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7207 | |
7208 | again: | |
e7850595 | 7209 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7210 | if (val < 0) |
7211 | return 0; | |
15dbf27c | 7212 | |
7b4b6658 PZ |
7213 | nr = div64_u64(period + val, period); |
7214 | offset = nr * period; | |
7215 | val -= offset; | |
e7850595 | 7216 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7217 | goto again; |
15dbf27c | 7218 | |
7b4b6658 | 7219 | return nr; |
15dbf27c PZ |
7220 | } |
7221 | ||
0cff784a | 7222 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7223 | struct perf_sample_data *data, |
5622f295 | 7224 | struct pt_regs *regs) |
15dbf27c | 7225 | { |
cdd6c482 | 7226 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7227 | int throttle = 0; |
15dbf27c | 7228 | |
0cff784a PZ |
7229 | if (!overflow) |
7230 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7231 | |
7b4b6658 PZ |
7232 | if (hwc->interrupts == MAX_INTERRUPTS) |
7233 | return; | |
15dbf27c | 7234 | |
7b4b6658 | 7235 | for (; overflow; overflow--) { |
a8b0ca17 | 7236 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7237 | data, regs)) { |
7b4b6658 PZ |
7238 | /* |
7239 | * We inhibit the overflow from happening when | |
7240 | * hwc->interrupts == MAX_INTERRUPTS. | |
7241 | */ | |
7242 | break; | |
7243 | } | |
cf450a73 | 7244 | throttle = 1; |
7b4b6658 | 7245 | } |
15dbf27c PZ |
7246 | } |
7247 | ||
a4eaf7f1 | 7248 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7249 | struct perf_sample_data *data, |
5622f295 | 7250 | struct pt_regs *regs) |
7b4b6658 | 7251 | { |
cdd6c482 | 7252 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7253 | |
e7850595 | 7254 | local64_add(nr, &event->count); |
d6d020e9 | 7255 | |
0cff784a PZ |
7256 | if (!regs) |
7257 | return; | |
7258 | ||
6c7e550f | 7259 | if (!is_sampling_event(event)) |
7b4b6658 | 7260 | return; |
d6d020e9 | 7261 | |
5d81e5cf AV |
7262 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7263 | data->period = nr; | |
7264 | return perf_swevent_overflow(event, 1, data, regs); | |
7265 | } else | |
7266 | data->period = event->hw.last_period; | |
7267 | ||
0cff784a | 7268 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7269 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7270 | |
e7850595 | 7271 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7272 | return; |
df1a132b | 7273 | |
a8b0ca17 | 7274 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7275 | } |
7276 | ||
f5ffe02e FW |
7277 | static int perf_exclude_event(struct perf_event *event, |
7278 | struct pt_regs *regs) | |
7279 | { | |
a4eaf7f1 | 7280 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7281 | return 1; |
a4eaf7f1 | 7282 | |
f5ffe02e FW |
7283 | if (regs) { |
7284 | if (event->attr.exclude_user && user_mode(regs)) | |
7285 | return 1; | |
7286 | ||
7287 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7288 | return 1; | |
7289 | } | |
7290 | ||
7291 | return 0; | |
7292 | } | |
7293 | ||
cdd6c482 | 7294 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7295 | enum perf_type_id type, |
6fb2915d LZ |
7296 | u32 event_id, |
7297 | struct perf_sample_data *data, | |
7298 | struct pt_regs *regs) | |
15dbf27c | 7299 | { |
cdd6c482 | 7300 | if (event->attr.type != type) |
a21ca2ca | 7301 | return 0; |
f5ffe02e | 7302 | |
cdd6c482 | 7303 | if (event->attr.config != event_id) |
15dbf27c PZ |
7304 | return 0; |
7305 | ||
f5ffe02e FW |
7306 | if (perf_exclude_event(event, regs)) |
7307 | return 0; | |
15dbf27c PZ |
7308 | |
7309 | return 1; | |
7310 | } | |
7311 | ||
76e1d904 FW |
7312 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7313 | { | |
7314 | u64 val = event_id | (type << 32); | |
7315 | ||
7316 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7317 | } | |
7318 | ||
49f135ed FW |
7319 | static inline struct hlist_head * |
7320 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7321 | { |
49f135ed FW |
7322 | u64 hash = swevent_hash(type, event_id); |
7323 | ||
7324 | return &hlist->heads[hash]; | |
7325 | } | |
76e1d904 | 7326 | |
49f135ed FW |
7327 | /* For the read side: events when they trigger */ |
7328 | static inline struct hlist_head * | |
b28ab83c | 7329 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7330 | { |
7331 | struct swevent_hlist *hlist; | |
76e1d904 | 7332 | |
b28ab83c | 7333 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7334 | if (!hlist) |
7335 | return NULL; | |
7336 | ||
49f135ed FW |
7337 | return __find_swevent_head(hlist, type, event_id); |
7338 | } | |
7339 | ||
7340 | /* For the event head insertion and removal in the hlist */ | |
7341 | static inline struct hlist_head * | |
b28ab83c | 7342 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7343 | { |
7344 | struct swevent_hlist *hlist; | |
7345 | u32 event_id = event->attr.config; | |
7346 | u64 type = event->attr.type; | |
7347 | ||
7348 | /* | |
7349 | * Event scheduling is always serialized against hlist allocation | |
7350 | * and release. Which makes the protected version suitable here. | |
7351 | * The context lock guarantees that. | |
7352 | */ | |
b28ab83c | 7353 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7354 | lockdep_is_held(&event->ctx->lock)); |
7355 | if (!hlist) | |
7356 | return NULL; | |
7357 | ||
7358 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7359 | } |
7360 | ||
7361 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7362 | u64 nr, |
76e1d904 FW |
7363 | struct perf_sample_data *data, |
7364 | struct pt_regs *regs) | |
15dbf27c | 7365 | { |
4a32fea9 | 7366 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7367 | struct perf_event *event; |
76e1d904 | 7368 | struct hlist_head *head; |
15dbf27c | 7369 | |
76e1d904 | 7370 | rcu_read_lock(); |
b28ab83c | 7371 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7372 | if (!head) |
7373 | goto end; | |
7374 | ||
b67bfe0d | 7375 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7376 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7377 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7378 | } |
76e1d904 FW |
7379 | end: |
7380 | rcu_read_unlock(); | |
15dbf27c PZ |
7381 | } |
7382 | ||
86038c5e PZI |
7383 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7384 | ||
4ed7c92d | 7385 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7386 | { |
4a32fea9 | 7387 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7388 | |
b28ab83c | 7389 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7390 | } |
645e8cc0 | 7391 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7392 | |
98b5c2c6 | 7393 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7394 | { |
4a32fea9 | 7395 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7396 | |
b28ab83c | 7397 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7398 | } |
15dbf27c | 7399 | |
86038c5e | 7400 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7401 | { |
a4234bfc | 7402 | struct perf_sample_data data; |
4ed7c92d | 7403 | |
86038c5e | 7404 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7405 | return; |
a4234bfc | 7406 | |
fd0d000b | 7407 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7408 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7409 | } |
7410 | ||
7411 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7412 | { | |
7413 | int rctx; | |
7414 | ||
7415 | preempt_disable_notrace(); | |
7416 | rctx = perf_swevent_get_recursion_context(); | |
7417 | if (unlikely(rctx < 0)) | |
7418 | goto fail; | |
7419 | ||
7420 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7421 | |
7422 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7423 | fail: |
1c024eca | 7424 | preempt_enable_notrace(); |
b8e83514 PZ |
7425 | } |
7426 | ||
cdd6c482 | 7427 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7428 | { |
15dbf27c PZ |
7429 | } |
7430 | ||
a4eaf7f1 | 7431 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7432 | { |
4a32fea9 | 7433 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7434 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7435 | struct hlist_head *head; |
7436 | ||
6c7e550f | 7437 | if (is_sampling_event(event)) { |
7b4b6658 | 7438 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7439 | perf_swevent_set_period(event); |
7b4b6658 | 7440 | } |
76e1d904 | 7441 | |
a4eaf7f1 PZ |
7442 | hwc->state = !(flags & PERF_EF_START); |
7443 | ||
b28ab83c | 7444 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7445 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7446 | return -EINVAL; |
7447 | ||
7448 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7449 | perf_event_update_userpage(event); |
76e1d904 | 7450 | |
15dbf27c PZ |
7451 | return 0; |
7452 | } | |
7453 | ||
a4eaf7f1 | 7454 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7455 | { |
76e1d904 | 7456 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7457 | } |
7458 | ||
a4eaf7f1 | 7459 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7460 | { |
a4eaf7f1 | 7461 | event->hw.state = 0; |
d6d020e9 | 7462 | } |
aa9c4c0f | 7463 | |
a4eaf7f1 | 7464 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7465 | { |
a4eaf7f1 | 7466 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7467 | } |
7468 | ||
49f135ed FW |
7469 | /* Deref the hlist from the update side */ |
7470 | static inline struct swevent_hlist * | |
b28ab83c | 7471 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7472 | { |
b28ab83c PZ |
7473 | return rcu_dereference_protected(swhash->swevent_hlist, |
7474 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7475 | } |
7476 | ||
b28ab83c | 7477 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7478 | { |
b28ab83c | 7479 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7480 | |
49f135ed | 7481 | if (!hlist) |
76e1d904 FW |
7482 | return; |
7483 | ||
70691d4a | 7484 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7485 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7486 | } |
7487 | ||
3b364d7b | 7488 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7489 | { |
b28ab83c | 7490 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7491 | |
b28ab83c | 7492 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7493 | |
b28ab83c PZ |
7494 | if (!--swhash->hlist_refcount) |
7495 | swevent_hlist_release(swhash); | |
76e1d904 | 7496 | |
b28ab83c | 7497 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7498 | } |
7499 | ||
3b364d7b | 7500 | static void swevent_hlist_put(void) |
76e1d904 FW |
7501 | { |
7502 | int cpu; | |
7503 | ||
76e1d904 | 7504 | for_each_possible_cpu(cpu) |
3b364d7b | 7505 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7506 | } |
7507 | ||
3b364d7b | 7508 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7509 | { |
b28ab83c | 7510 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7511 | int err = 0; |
7512 | ||
b28ab83c | 7513 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7514 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7515 | struct swevent_hlist *hlist; |
7516 | ||
7517 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7518 | if (!hlist) { | |
7519 | err = -ENOMEM; | |
7520 | goto exit; | |
7521 | } | |
b28ab83c | 7522 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7523 | } |
b28ab83c | 7524 | swhash->hlist_refcount++; |
9ed6060d | 7525 | exit: |
b28ab83c | 7526 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7527 | |
7528 | return err; | |
7529 | } | |
7530 | ||
3b364d7b | 7531 | static int swevent_hlist_get(void) |
76e1d904 | 7532 | { |
3b364d7b | 7533 | int err, cpu, failed_cpu; |
76e1d904 | 7534 | |
76e1d904 FW |
7535 | get_online_cpus(); |
7536 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7537 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7538 | if (err) { |
7539 | failed_cpu = cpu; | |
7540 | goto fail; | |
7541 | } | |
7542 | } | |
7543 | put_online_cpus(); | |
7544 | ||
7545 | return 0; | |
9ed6060d | 7546 | fail: |
76e1d904 FW |
7547 | for_each_possible_cpu(cpu) { |
7548 | if (cpu == failed_cpu) | |
7549 | break; | |
3b364d7b | 7550 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7551 | } |
7552 | ||
7553 | put_online_cpus(); | |
7554 | return err; | |
7555 | } | |
7556 | ||
c5905afb | 7557 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7558 | |
b0a873eb PZ |
7559 | static void sw_perf_event_destroy(struct perf_event *event) |
7560 | { | |
7561 | u64 event_id = event->attr.config; | |
95476b64 | 7562 | |
b0a873eb PZ |
7563 | WARN_ON(event->parent); |
7564 | ||
c5905afb | 7565 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7566 | swevent_hlist_put(); |
b0a873eb PZ |
7567 | } |
7568 | ||
7569 | static int perf_swevent_init(struct perf_event *event) | |
7570 | { | |
8176cced | 7571 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7572 | |
7573 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7574 | return -ENOENT; | |
7575 | ||
2481c5fa SE |
7576 | /* |
7577 | * no branch sampling for software events | |
7578 | */ | |
7579 | if (has_branch_stack(event)) | |
7580 | return -EOPNOTSUPP; | |
7581 | ||
b0a873eb PZ |
7582 | switch (event_id) { |
7583 | case PERF_COUNT_SW_CPU_CLOCK: | |
7584 | case PERF_COUNT_SW_TASK_CLOCK: | |
7585 | return -ENOENT; | |
7586 | ||
7587 | default: | |
7588 | break; | |
7589 | } | |
7590 | ||
ce677831 | 7591 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7592 | return -ENOENT; |
7593 | ||
7594 | if (!event->parent) { | |
7595 | int err; | |
7596 | ||
3b364d7b | 7597 | err = swevent_hlist_get(); |
b0a873eb PZ |
7598 | if (err) |
7599 | return err; | |
7600 | ||
c5905afb | 7601 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7602 | event->destroy = sw_perf_event_destroy; |
7603 | } | |
7604 | ||
7605 | return 0; | |
7606 | } | |
7607 | ||
7608 | static struct pmu perf_swevent = { | |
89a1e187 | 7609 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7610 | |
34f43927 PZ |
7611 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7612 | ||
b0a873eb | 7613 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7614 | .add = perf_swevent_add, |
7615 | .del = perf_swevent_del, | |
7616 | .start = perf_swevent_start, | |
7617 | .stop = perf_swevent_stop, | |
1c024eca | 7618 | .read = perf_swevent_read, |
1c024eca PZ |
7619 | }; |
7620 | ||
b0a873eb PZ |
7621 | #ifdef CONFIG_EVENT_TRACING |
7622 | ||
1c024eca PZ |
7623 | static int perf_tp_filter_match(struct perf_event *event, |
7624 | struct perf_sample_data *data) | |
7625 | { | |
7e3f977e | 7626 | void *record = data->raw->frag.data; |
1c024eca | 7627 | |
b71b437e PZ |
7628 | /* only top level events have filters set */ |
7629 | if (event->parent) | |
7630 | event = event->parent; | |
7631 | ||
1c024eca PZ |
7632 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7633 | return 1; | |
7634 | return 0; | |
7635 | } | |
7636 | ||
7637 | static int perf_tp_event_match(struct perf_event *event, | |
7638 | struct perf_sample_data *data, | |
7639 | struct pt_regs *regs) | |
7640 | { | |
a0f7d0f7 FW |
7641 | if (event->hw.state & PERF_HES_STOPPED) |
7642 | return 0; | |
580d607c PZ |
7643 | /* |
7644 | * All tracepoints are from kernel-space. | |
7645 | */ | |
7646 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7647 | return 0; |
7648 | ||
7649 | if (!perf_tp_filter_match(event, data)) | |
7650 | return 0; | |
7651 | ||
7652 | return 1; | |
7653 | } | |
7654 | ||
85b67bcb AS |
7655 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7656 | struct trace_event_call *call, u64 count, | |
7657 | struct pt_regs *regs, struct hlist_head *head, | |
7658 | struct task_struct *task) | |
7659 | { | |
7660 | struct bpf_prog *prog = call->prog; | |
7661 | ||
7662 | if (prog) { | |
7663 | *(struct pt_regs **)raw_data = regs; | |
7664 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7665 | perf_swevent_put_recursion_context(rctx); | |
7666 | return; | |
7667 | } | |
7668 | } | |
7669 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7670 | rctx, task); | |
7671 | } | |
7672 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7673 | ||
1e1dcd93 | 7674 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7675 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7676 | struct task_struct *task) | |
95476b64 FW |
7677 | { |
7678 | struct perf_sample_data data; | |
1c024eca | 7679 | struct perf_event *event; |
1c024eca | 7680 | |
95476b64 | 7681 | struct perf_raw_record raw = { |
7e3f977e DB |
7682 | .frag = { |
7683 | .size = entry_size, | |
7684 | .data = record, | |
7685 | }, | |
95476b64 FW |
7686 | }; |
7687 | ||
1e1dcd93 | 7688 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7689 | data.raw = &raw; |
7690 | ||
1e1dcd93 AS |
7691 | perf_trace_buf_update(record, event_type); |
7692 | ||
b67bfe0d | 7693 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7694 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7695 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7696 | } |
ecc55f84 | 7697 | |
e6dab5ff AV |
7698 | /* |
7699 | * If we got specified a target task, also iterate its context and | |
7700 | * deliver this event there too. | |
7701 | */ | |
7702 | if (task && task != current) { | |
7703 | struct perf_event_context *ctx; | |
7704 | struct trace_entry *entry = record; | |
7705 | ||
7706 | rcu_read_lock(); | |
7707 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7708 | if (!ctx) | |
7709 | goto unlock; | |
7710 | ||
7711 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7712 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7713 | continue; | |
7714 | if (event->attr.config != entry->type) | |
7715 | continue; | |
7716 | if (perf_tp_event_match(event, &data, regs)) | |
7717 | perf_swevent_event(event, count, &data, regs); | |
7718 | } | |
7719 | unlock: | |
7720 | rcu_read_unlock(); | |
7721 | } | |
7722 | ||
ecc55f84 | 7723 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7724 | } |
7725 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7726 | ||
cdd6c482 | 7727 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7728 | { |
1c024eca | 7729 | perf_trace_destroy(event); |
e077df4f PZ |
7730 | } |
7731 | ||
b0a873eb | 7732 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7733 | { |
76e1d904 FW |
7734 | int err; |
7735 | ||
b0a873eb PZ |
7736 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7737 | return -ENOENT; | |
7738 | ||
2481c5fa SE |
7739 | /* |
7740 | * no branch sampling for tracepoint events | |
7741 | */ | |
7742 | if (has_branch_stack(event)) | |
7743 | return -EOPNOTSUPP; | |
7744 | ||
1c024eca PZ |
7745 | err = perf_trace_init(event); |
7746 | if (err) | |
b0a873eb | 7747 | return err; |
e077df4f | 7748 | |
cdd6c482 | 7749 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7750 | |
b0a873eb PZ |
7751 | return 0; |
7752 | } | |
7753 | ||
7754 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7755 | .task_ctx_nr = perf_sw_context, |
7756 | ||
b0a873eb | 7757 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7758 | .add = perf_trace_add, |
7759 | .del = perf_trace_del, | |
7760 | .start = perf_swevent_start, | |
7761 | .stop = perf_swevent_stop, | |
b0a873eb | 7762 | .read = perf_swevent_read, |
b0a873eb PZ |
7763 | }; |
7764 | ||
7765 | static inline void perf_tp_register(void) | |
7766 | { | |
2e80a82a | 7767 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7768 | } |
6fb2915d | 7769 | |
6fb2915d LZ |
7770 | static void perf_event_free_filter(struct perf_event *event) |
7771 | { | |
7772 | ftrace_profile_free_filter(event); | |
7773 | } | |
7774 | ||
aa6a5f3c AS |
7775 | #ifdef CONFIG_BPF_SYSCALL |
7776 | static void bpf_overflow_handler(struct perf_event *event, | |
7777 | struct perf_sample_data *data, | |
7778 | struct pt_regs *regs) | |
7779 | { | |
7780 | struct bpf_perf_event_data_kern ctx = { | |
7781 | .data = data, | |
7782 | .regs = regs, | |
7783 | }; | |
7784 | int ret = 0; | |
7785 | ||
7786 | preempt_disable(); | |
7787 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
7788 | goto out; | |
7789 | rcu_read_lock(); | |
88575199 | 7790 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
7791 | rcu_read_unlock(); |
7792 | out: | |
7793 | __this_cpu_dec(bpf_prog_active); | |
7794 | preempt_enable(); | |
7795 | if (!ret) | |
7796 | return; | |
7797 | ||
7798 | event->orig_overflow_handler(event, data, regs); | |
7799 | } | |
7800 | ||
7801 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7802 | { | |
7803 | struct bpf_prog *prog; | |
7804 | ||
7805 | if (event->overflow_handler_context) | |
7806 | /* hw breakpoint or kernel counter */ | |
7807 | return -EINVAL; | |
7808 | ||
7809 | if (event->prog) | |
7810 | return -EEXIST; | |
7811 | ||
7812 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
7813 | if (IS_ERR(prog)) | |
7814 | return PTR_ERR(prog); | |
7815 | ||
7816 | event->prog = prog; | |
7817 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
7818 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
7819 | return 0; | |
7820 | } | |
7821 | ||
7822 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7823 | { | |
7824 | struct bpf_prog *prog = event->prog; | |
7825 | ||
7826 | if (!prog) | |
7827 | return; | |
7828 | ||
7829 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
7830 | event->prog = NULL; | |
7831 | bpf_prog_put(prog); | |
7832 | } | |
7833 | #else | |
7834 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7835 | { | |
7836 | return -EOPNOTSUPP; | |
7837 | } | |
7838 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7839 | { | |
7840 | } | |
7841 | #endif | |
7842 | ||
2541517c AS |
7843 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7844 | { | |
98b5c2c6 | 7845 | bool is_kprobe, is_tracepoint; |
2541517c AS |
7846 | struct bpf_prog *prog; |
7847 | ||
aa6a5f3c AS |
7848 | if (event->attr.type == PERF_TYPE_HARDWARE || |
7849 | event->attr.type == PERF_TYPE_SOFTWARE) | |
7850 | return perf_event_set_bpf_handler(event, prog_fd); | |
7851 | ||
2541517c AS |
7852 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7853 | return -EINVAL; | |
7854 | ||
7855 | if (event->tp_event->prog) | |
7856 | return -EEXIST; | |
7857 | ||
98b5c2c6 AS |
7858 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
7859 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
7860 | if (!is_kprobe && !is_tracepoint) | |
7861 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
7862 | return -EINVAL; |
7863 | ||
7864 | prog = bpf_prog_get(prog_fd); | |
7865 | if (IS_ERR(prog)) | |
7866 | return PTR_ERR(prog); | |
7867 | ||
98b5c2c6 AS |
7868 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
7869 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
7870 | /* valid fd, but invalid bpf program type */ |
7871 | bpf_prog_put(prog); | |
7872 | return -EINVAL; | |
7873 | } | |
7874 | ||
32bbe007 AS |
7875 | if (is_tracepoint) { |
7876 | int off = trace_event_get_offsets(event->tp_event); | |
7877 | ||
7878 | if (prog->aux->max_ctx_offset > off) { | |
7879 | bpf_prog_put(prog); | |
7880 | return -EACCES; | |
7881 | } | |
7882 | } | |
2541517c AS |
7883 | event->tp_event->prog = prog; |
7884 | ||
7885 | return 0; | |
7886 | } | |
7887 | ||
7888 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7889 | { | |
7890 | struct bpf_prog *prog; | |
7891 | ||
aa6a5f3c AS |
7892 | perf_event_free_bpf_handler(event); |
7893 | ||
2541517c AS |
7894 | if (!event->tp_event) |
7895 | return; | |
7896 | ||
7897 | prog = event->tp_event->prog; | |
7898 | if (prog) { | |
7899 | event->tp_event->prog = NULL; | |
1aacde3d | 7900 | bpf_prog_put(prog); |
2541517c AS |
7901 | } |
7902 | } | |
7903 | ||
e077df4f | 7904 | #else |
6fb2915d | 7905 | |
b0a873eb | 7906 | static inline void perf_tp_register(void) |
e077df4f | 7907 | { |
e077df4f | 7908 | } |
6fb2915d | 7909 | |
6fb2915d LZ |
7910 | static void perf_event_free_filter(struct perf_event *event) |
7911 | { | |
7912 | } | |
7913 | ||
2541517c AS |
7914 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7915 | { | |
7916 | return -ENOENT; | |
7917 | } | |
7918 | ||
7919 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7920 | { | |
7921 | } | |
07b139c8 | 7922 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7923 | |
24f1e32c | 7924 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7925 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7926 | { |
f5ffe02e FW |
7927 | struct perf_sample_data sample; |
7928 | struct pt_regs *regs = data; | |
7929 | ||
fd0d000b | 7930 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7931 | |
a4eaf7f1 | 7932 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7933 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7934 | } |
7935 | #endif | |
7936 | ||
375637bc AS |
7937 | /* |
7938 | * Allocate a new address filter | |
7939 | */ | |
7940 | static struct perf_addr_filter * | |
7941 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
7942 | { | |
7943 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
7944 | struct perf_addr_filter *filter; | |
7945 | ||
7946 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
7947 | if (!filter) | |
7948 | return NULL; | |
7949 | ||
7950 | INIT_LIST_HEAD(&filter->entry); | |
7951 | list_add_tail(&filter->entry, filters); | |
7952 | ||
7953 | return filter; | |
7954 | } | |
7955 | ||
7956 | static void free_filters_list(struct list_head *filters) | |
7957 | { | |
7958 | struct perf_addr_filter *filter, *iter; | |
7959 | ||
7960 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
7961 | if (filter->inode) | |
7962 | iput(filter->inode); | |
7963 | list_del(&filter->entry); | |
7964 | kfree(filter); | |
7965 | } | |
7966 | } | |
7967 | ||
7968 | /* | |
7969 | * Free existing address filters and optionally install new ones | |
7970 | */ | |
7971 | static void perf_addr_filters_splice(struct perf_event *event, | |
7972 | struct list_head *head) | |
7973 | { | |
7974 | unsigned long flags; | |
7975 | LIST_HEAD(list); | |
7976 | ||
7977 | if (!has_addr_filter(event)) | |
7978 | return; | |
7979 | ||
7980 | /* don't bother with children, they don't have their own filters */ | |
7981 | if (event->parent) | |
7982 | return; | |
7983 | ||
7984 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
7985 | ||
7986 | list_splice_init(&event->addr_filters.list, &list); | |
7987 | if (head) | |
7988 | list_splice(head, &event->addr_filters.list); | |
7989 | ||
7990 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
7991 | ||
7992 | free_filters_list(&list); | |
7993 | } | |
7994 | ||
7995 | /* | |
7996 | * Scan through mm's vmas and see if one of them matches the | |
7997 | * @filter; if so, adjust filter's address range. | |
7998 | * Called with mm::mmap_sem down for reading. | |
7999 | */ | |
8000 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8001 | struct mm_struct *mm) | |
8002 | { | |
8003 | struct vm_area_struct *vma; | |
8004 | ||
8005 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8006 | struct file *file = vma->vm_file; | |
8007 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8008 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8009 | ||
8010 | if (!file) | |
8011 | continue; | |
8012 | ||
8013 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8014 | continue; | |
8015 | ||
8016 | return vma->vm_start; | |
8017 | } | |
8018 | ||
8019 | return 0; | |
8020 | } | |
8021 | ||
8022 | /* | |
8023 | * Update event's address range filters based on the | |
8024 | * task's existing mappings, if any. | |
8025 | */ | |
8026 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8027 | { | |
8028 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8029 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8030 | struct perf_addr_filter *filter; | |
8031 | struct mm_struct *mm = NULL; | |
8032 | unsigned int count = 0; | |
8033 | unsigned long flags; | |
8034 | ||
8035 | /* | |
8036 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8037 | * will stop on the parent's child_mutex that our caller is also holding | |
8038 | */ | |
8039 | if (task == TASK_TOMBSTONE) | |
8040 | return; | |
8041 | ||
8042 | mm = get_task_mm(event->ctx->task); | |
8043 | if (!mm) | |
8044 | goto restart; | |
8045 | ||
8046 | down_read(&mm->mmap_sem); | |
8047 | ||
8048 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8049 | list_for_each_entry(filter, &ifh->list, entry) { | |
8050 | event->addr_filters_offs[count] = 0; | |
8051 | ||
99f5bc9b MP |
8052 | /* |
8053 | * Adjust base offset if the filter is associated to a binary | |
8054 | * that needs to be mapped: | |
8055 | */ | |
8056 | if (filter->inode) | |
375637bc AS |
8057 | event->addr_filters_offs[count] = |
8058 | perf_addr_filter_apply(filter, mm); | |
8059 | ||
8060 | count++; | |
8061 | } | |
8062 | ||
8063 | event->addr_filters_gen++; | |
8064 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8065 | ||
8066 | up_read(&mm->mmap_sem); | |
8067 | ||
8068 | mmput(mm); | |
8069 | ||
8070 | restart: | |
767ae086 | 8071 | perf_event_stop(event, 1); |
375637bc AS |
8072 | } |
8073 | ||
8074 | /* | |
8075 | * Address range filtering: limiting the data to certain | |
8076 | * instruction address ranges. Filters are ioctl()ed to us from | |
8077 | * userspace as ascii strings. | |
8078 | * | |
8079 | * Filter string format: | |
8080 | * | |
8081 | * ACTION RANGE_SPEC | |
8082 | * where ACTION is one of the | |
8083 | * * "filter": limit the trace to this region | |
8084 | * * "start": start tracing from this address | |
8085 | * * "stop": stop tracing at this address/region; | |
8086 | * RANGE_SPEC is | |
8087 | * * for kernel addresses: <start address>[/<size>] | |
8088 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8089 | * | |
8090 | * if <size> is not specified, the range is treated as a single address. | |
8091 | */ | |
8092 | enum { | |
e96271f3 | 8093 | IF_ACT_NONE = -1, |
375637bc AS |
8094 | IF_ACT_FILTER, |
8095 | IF_ACT_START, | |
8096 | IF_ACT_STOP, | |
8097 | IF_SRC_FILE, | |
8098 | IF_SRC_KERNEL, | |
8099 | IF_SRC_FILEADDR, | |
8100 | IF_SRC_KERNELADDR, | |
8101 | }; | |
8102 | ||
8103 | enum { | |
8104 | IF_STATE_ACTION = 0, | |
8105 | IF_STATE_SOURCE, | |
8106 | IF_STATE_END, | |
8107 | }; | |
8108 | ||
8109 | static const match_table_t if_tokens = { | |
8110 | { IF_ACT_FILTER, "filter" }, | |
8111 | { IF_ACT_START, "start" }, | |
8112 | { IF_ACT_STOP, "stop" }, | |
8113 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8114 | { IF_SRC_KERNEL, "%u/%u" }, | |
8115 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8116 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8117 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8118 | }; |
8119 | ||
8120 | /* | |
8121 | * Address filter string parser | |
8122 | */ | |
8123 | static int | |
8124 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8125 | struct list_head *filters) | |
8126 | { | |
8127 | struct perf_addr_filter *filter = NULL; | |
8128 | char *start, *orig, *filename = NULL; | |
8129 | struct path path; | |
8130 | substring_t args[MAX_OPT_ARGS]; | |
8131 | int state = IF_STATE_ACTION, token; | |
8132 | unsigned int kernel = 0; | |
8133 | int ret = -EINVAL; | |
8134 | ||
8135 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8136 | if (!fstr) | |
8137 | return -ENOMEM; | |
8138 | ||
8139 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8140 | ret = -EINVAL; | |
8141 | ||
8142 | if (!*start) | |
8143 | continue; | |
8144 | ||
8145 | /* filter definition begins */ | |
8146 | if (state == IF_STATE_ACTION) { | |
8147 | filter = perf_addr_filter_new(event, filters); | |
8148 | if (!filter) | |
8149 | goto fail; | |
8150 | } | |
8151 | ||
8152 | token = match_token(start, if_tokens, args); | |
8153 | switch (token) { | |
8154 | case IF_ACT_FILTER: | |
8155 | case IF_ACT_START: | |
8156 | filter->filter = 1; | |
8157 | ||
8158 | case IF_ACT_STOP: | |
8159 | if (state != IF_STATE_ACTION) | |
8160 | goto fail; | |
8161 | ||
8162 | state = IF_STATE_SOURCE; | |
8163 | break; | |
8164 | ||
8165 | case IF_SRC_KERNELADDR: | |
8166 | case IF_SRC_KERNEL: | |
8167 | kernel = 1; | |
8168 | ||
8169 | case IF_SRC_FILEADDR: | |
8170 | case IF_SRC_FILE: | |
8171 | if (state != IF_STATE_SOURCE) | |
8172 | goto fail; | |
8173 | ||
8174 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8175 | filter->range = 1; | |
8176 | ||
8177 | *args[0].to = 0; | |
8178 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8179 | if (ret) | |
8180 | goto fail; | |
8181 | ||
8182 | if (filter->range) { | |
8183 | *args[1].to = 0; | |
8184 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8185 | if (ret) | |
8186 | goto fail; | |
8187 | } | |
8188 | ||
4059ffd0 MP |
8189 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8190 | int fpos = filter->range ? 2 : 1; | |
8191 | ||
8192 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8193 | if (!filename) { |
8194 | ret = -ENOMEM; | |
8195 | goto fail; | |
8196 | } | |
8197 | } | |
8198 | ||
8199 | state = IF_STATE_END; | |
8200 | break; | |
8201 | ||
8202 | default: | |
8203 | goto fail; | |
8204 | } | |
8205 | ||
8206 | /* | |
8207 | * Filter definition is fully parsed, validate and install it. | |
8208 | * Make sure that it doesn't contradict itself or the event's | |
8209 | * attribute. | |
8210 | */ | |
8211 | if (state == IF_STATE_END) { | |
8212 | if (kernel && event->attr.exclude_kernel) | |
8213 | goto fail; | |
8214 | ||
8215 | if (!kernel) { | |
8216 | if (!filename) | |
8217 | goto fail; | |
8218 | ||
8219 | /* look up the path and grab its inode */ | |
8220 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8221 | if (ret) | |
8222 | goto fail_free_name; | |
8223 | ||
8224 | filter->inode = igrab(d_inode(path.dentry)); | |
8225 | path_put(&path); | |
8226 | kfree(filename); | |
8227 | filename = NULL; | |
8228 | ||
8229 | ret = -EINVAL; | |
8230 | if (!filter->inode || | |
8231 | !S_ISREG(filter->inode->i_mode)) | |
8232 | /* free_filters_list() will iput() */ | |
8233 | goto fail; | |
8234 | } | |
8235 | ||
8236 | /* ready to consume more filters */ | |
8237 | state = IF_STATE_ACTION; | |
8238 | filter = NULL; | |
8239 | } | |
8240 | } | |
8241 | ||
8242 | if (state != IF_STATE_ACTION) | |
8243 | goto fail; | |
8244 | ||
8245 | kfree(orig); | |
8246 | ||
8247 | return 0; | |
8248 | ||
8249 | fail_free_name: | |
8250 | kfree(filename); | |
8251 | fail: | |
8252 | free_filters_list(filters); | |
8253 | kfree(orig); | |
8254 | ||
8255 | return ret; | |
8256 | } | |
8257 | ||
8258 | static int | |
8259 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8260 | { | |
8261 | LIST_HEAD(filters); | |
8262 | int ret; | |
8263 | ||
8264 | /* | |
8265 | * Since this is called in perf_ioctl() path, we're already holding | |
8266 | * ctx::mutex. | |
8267 | */ | |
8268 | lockdep_assert_held(&event->ctx->mutex); | |
8269 | ||
8270 | if (WARN_ON_ONCE(event->parent)) | |
8271 | return -EINVAL; | |
8272 | ||
8273 | /* | |
8274 | * For now, we only support filtering in per-task events; doing so | |
8275 | * for CPU-wide events requires additional context switching trickery, | |
8276 | * since same object code will be mapped at different virtual | |
8277 | * addresses in different processes. | |
8278 | */ | |
8279 | if (!event->ctx->task) | |
8280 | return -EOPNOTSUPP; | |
8281 | ||
8282 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); | |
8283 | if (ret) | |
8284 | return ret; | |
8285 | ||
8286 | ret = event->pmu->addr_filters_validate(&filters); | |
8287 | if (ret) { | |
8288 | free_filters_list(&filters); | |
8289 | return ret; | |
8290 | } | |
8291 | ||
8292 | /* remove existing filters, if any */ | |
8293 | perf_addr_filters_splice(event, &filters); | |
8294 | ||
8295 | /* install new filters */ | |
8296 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8297 | ||
8298 | return ret; | |
8299 | } | |
8300 | ||
c796bbbe AS |
8301 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8302 | { | |
8303 | char *filter_str; | |
8304 | int ret = -EINVAL; | |
8305 | ||
375637bc AS |
8306 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8307 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8308 | !has_addr_filter(event)) | |
c796bbbe AS |
8309 | return -EINVAL; |
8310 | ||
8311 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8312 | if (IS_ERR(filter_str)) | |
8313 | return PTR_ERR(filter_str); | |
8314 | ||
8315 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8316 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8317 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8318 | filter_str); | |
375637bc AS |
8319 | else if (has_addr_filter(event)) |
8320 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8321 | |
8322 | kfree(filter_str); | |
8323 | return ret; | |
8324 | } | |
8325 | ||
b0a873eb PZ |
8326 | /* |
8327 | * hrtimer based swevent callback | |
8328 | */ | |
f29ac756 | 8329 | |
b0a873eb | 8330 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8331 | { |
b0a873eb PZ |
8332 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8333 | struct perf_sample_data data; | |
8334 | struct pt_regs *regs; | |
8335 | struct perf_event *event; | |
8336 | u64 period; | |
f29ac756 | 8337 | |
b0a873eb | 8338 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8339 | |
8340 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8341 | return HRTIMER_NORESTART; | |
8342 | ||
b0a873eb | 8343 | event->pmu->read(event); |
f344011c | 8344 | |
fd0d000b | 8345 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8346 | regs = get_irq_regs(); |
8347 | ||
8348 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8349 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8350 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8351 | ret = HRTIMER_NORESTART; |
8352 | } | |
24f1e32c | 8353 | |
b0a873eb PZ |
8354 | period = max_t(u64, 10000, event->hw.sample_period); |
8355 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8356 | |
b0a873eb | 8357 | return ret; |
f29ac756 PZ |
8358 | } |
8359 | ||
b0a873eb | 8360 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8361 | { |
b0a873eb | 8362 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8363 | s64 period; |
8364 | ||
8365 | if (!is_sampling_event(event)) | |
8366 | return; | |
f5ffe02e | 8367 | |
5d508e82 FBH |
8368 | period = local64_read(&hwc->period_left); |
8369 | if (period) { | |
8370 | if (period < 0) | |
8371 | period = 10000; | |
fa407f35 | 8372 | |
5d508e82 FBH |
8373 | local64_set(&hwc->period_left, 0); |
8374 | } else { | |
8375 | period = max_t(u64, 10000, hwc->sample_period); | |
8376 | } | |
3497d206 TG |
8377 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8378 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8379 | } |
b0a873eb PZ |
8380 | |
8381 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8382 | { |
b0a873eb PZ |
8383 | struct hw_perf_event *hwc = &event->hw; |
8384 | ||
6c7e550f | 8385 | if (is_sampling_event(event)) { |
b0a873eb | 8386 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8387 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8388 | |
8389 | hrtimer_cancel(&hwc->hrtimer); | |
8390 | } | |
24f1e32c FW |
8391 | } |
8392 | ||
ba3dd36c PZ |
8393 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8394 | { | |
8395 | struct hw_perf_event *hwc = &event->hw; | |
8396 | ||
8397 | if (!is_sampling_event(event)) | |
8398 | return; | |
8399 | ||
8400 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8401 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8402 | ||
8403 | /* | |
8404 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8405 | * mapping and avoid the whole period adjust feedback stuff. | |
8406 | */ | |
8407 | if (event->attr.freq) { | |
8408 | long freq = event->attr.sample_freq; | |
8409 | ||
8410 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8411 | hwc->sample_period = event->attr.sample_period; | |
8412 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8413 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8414 | event->attr.freq = 0; |
8415 | } | |
8416 | } | |
8417 | ||
b0a873eb PZ |
8418 | /* |
8419 | * Software event: cpu wall time clock | |
8420 | */ | |
8421 | ||
8422 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8423 | { |
b0a873eb PZ |
8424 | s64 prev; |
8425 | u64 now; | |
8426 | ||
a4eaf7f1 | 8427 | now = local_clock(); |
b0a873eb PZ |
8428 | prev = local64_xchg(&event->hw.prev_count, now); |
8429 | local64_add(now - prev, &event->count); | |
24f1e32c | 8430 | } |
24f1e32c | 8431 | |
a4eaf7f1 | 8432 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8433 | { |
a4eaf7f1 | 8434 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8435 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8436 | } |
8437 | ||
a4eaf7f1 | 8438 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8439 | { |
b0a873eb PZ |
8440 | perf_swevent_cancel_hrtimer(event); |
8441 | cpu_clock_event_update(event); | |
8442 | } | |
f29ac756 | 8443 | |
a4eaf7f1 PZ |
8444 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8445 | { | |
8446 | if (flags & PERF_EF_START) | |
8447 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8448 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8449 | |
8450 | return 0; | |
8451 | } | |
8452 | ||
8453 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8454 | { | |
8455 | cpu_clock_event_stop(event, flags); | |
8456 | } | |
8457 | ||
b0a873eb PZ |
8458 | static void cpu_clock_event_read(struct perf_event *event) |
8459 | { | |
8460 | cpu_clock_event_update(event); | |
8461 | } | |
f344011c | 8462 | |
b0a873eb PZ |
8463 | static int cpu_clock_event_init(struct perf_event *event) |
8464 | { | |
8465 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8466 | return -ENOENT; | |
8467 | ||
8468 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8469 | return -ENOENT; | |
8470 | ||
2481c5fa SE |
8471 | /* |
8472 | * no branch sampling for software events | |
8473 | */ | |
8474 | if (has_branch_stack(event)) | |
8475 | return -EOPNOTSUPP; | |
8476 | ||
ba3dd36c PZ |
8477 | perf_swevent_init_hrtimer(event); |
8478 | ||
b0a873eb | 8479 | return 0; |
f29ac756 PZ |
8480 | } |
8481 | ||
b0a873eb | 8482 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8483 | .task_ctx_nr = perf_sw_context, |
8484 | ||
34f43927 PZ |
8485 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8486 | ||
b0a873eb | 8487 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8488 | .add = cpu_clock_event_add, |
8489 | .del = cpu_clock_event_del, | |
8490 | .start = cpu_clock_event_start, | |
8491 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8492 | .read = cpu_clock_event_read, |
8493 | }; | |
8494 | ||
8495 | /* | |
8496 | * Software event: task time clock | |
8497 | */ | |
8498 | ||
8499 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8500 | { |
b0a873eb PZ |
8501 | u64 prev; |
8502 | s64 delta; | |
5c92d124 | 8503 | |
b0a873eb PZ |
8504 | prev = local64_xchg(&event->hw.prev_count, now); |
8505 | delta = now - prev; | |
8506 | local64_add(delta, &event->count); | |
8507 | } | |
5c92d124 | 8508 | |
a4eaf7f1 | 8509 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8510 | { |
a4eaf7f1 | 8511 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8512 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8513 | } |
8514 | ||
a4eaf7f1 | 8515 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8516 | { |
8517 | perf_swevent_cancel_hrtimer(event); | |
8518 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8519 | } |
8520 | ||
8521 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8522 | { | |
8523 | if (flags & PERF_EF_START) | |
8524 | task_clock_event_start(event, flags); | |
6a694a60 | 8525 | perf_event_update_userpage(event); |
b0a873eb | 8526 | |
a4eaf7f1 PZ |
8527 | return 0; |
8528 | } | |
8529 | ||
8530 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8531 | { | |
8532 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8533 | } |
8534 | ||
8535 | static void task_clock_event_read(struct perf_event *event) | |
8536 | { | |
768a06e2 PZ |
8537 | u64 now = perf_clock(); |
8538 | u64 delta = now - event->ctx->timestamp; | |
8539 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8540 | |
8541 | task_clock_event_update(event, time); | |
8542 | } | |
8543 | ||
8544 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8545 | { |
b0a873eb PZ |
8546 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8547 | return -ENOENT; | |
8548 | ||
8549 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8550 | return -ENOENT; | |
8551 | ||
2481c5fa SE |
8552 | /* |
8553 | * no branch sampling for software events | |
8554 | */ | |
8555 | if (has_branch_stack(event)) | |
8556 | return -EOPNOTSUPP; | |
8557 | ||
ba3dd36c PZ |
8558 | perf_swevent_init_hrtimer(event); |
8559 | ||
b0a873eb | 8560 | return 0; |
6fb2915d LZ |
8561 | } |
8562 | ||
b0a873eb | 8563 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8564 | .task_ctx_nr = perf_sw_context, |
8565 | ||
34f43927 PZ |
8566 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8567 | ||
b0a873eb | 8568 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8569 | .add = task_clock_event_add, |
8570 | .del = task_clock_event_del, | |
8571 | .start = task_clock_event_start, | |
8572 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8573 | .read = task_clock_event_read, |
8574 | }; | |
6fb2915d | 8575 | |
ad5133b7 | 8576 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8577 | { |
e077df4f | 8578 | } |
6fb2915d | 8579 | |
fbbe0701 SB |
8580 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8581 | { | |
8582 | } | |
8583 | ||
ad5133b7 | 8584 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8585 | { |
ad5133b7 | 8586 | return 0; |
6fb2915d LZ |
8587 | } |
8588 | ||
18ab2cd3 | 8589 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8590 | |
8591 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8592 | { |
fbbe0701 SB |
8593 | __this_cpu_write(nop_txn_flags, flags); |
8594 | ||
8595 | if (flags & ~PERF_PMU_TXN_ADD) | |
8596 | return; | |
8597 | ||
ad5133b7 | 8598 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8599 | } |
8600 | ||
ad5133b7 PZ |
8601 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8602 | { | |
fbbe0701 SB |
8603 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8604 | ||
8605 | __this_cpu_write(nop_txn_flags, 0); | |
8606 | ||
8607 | if (flags & ~PERF_PMU_TXN_ADD) | |
8608 | return 0; | |
8609 | ||
ad5133b7 PZ |
8610 | perf_pmu_enable(pmu); |
8611 | return 0; | |
8612 | } | |
e077df4f | 8613 | |
ad5133b7 | 8614 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8615 | { |
fbbe0701 SB |
8616 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8617 | ||
8618 | __this_cpu_write(nop_txn_flags, 0); | |
8619 | ||
8620 | if (flags & ~PERF_PMU_TXN_ADD) | |
8621 | return; | |
8622 | ||
ad5133b7 | 8623 | perf_pmu_enable(pmu); |
24f1e32c FW |
8624 | } |
8625 | ||
35edc2a5 PZ |
8626 | static int perf_event_idx_default(struct perf_event *event) |
8627 | { | |
c719f560 | 8628 | return 0; |
35edc2a5 PZ |
8629 | } |
8630 | ||
8dc85d54 PZ |
8631 | /* |
8632 | * Ensures all contexts with the same task_ctx_nr have the same | |
8633 | * pmu_cpu_context too. | |
8634 | */ | |
9e317041 | 8635 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8636 | { |
8dc85d54 | 8637 | struct pmu *pmu; |
b326e956 | 8638 | |
8dc85d54 PZ |
8639 | if (ctxn < 0) |
8640 | return NULL; | |
24f1e32c | 8641 | |
8dc85d54 PZ |
8642 | list_for_each_entry(pmu, &pmus, entry) { |
8643 | if (pmu->task_ctx_nr == ctxn) | |
8644 | return pmu->pmu_cpu_context; | |
8645 | } | |
24f1e32c | 8646 | |
8dc85d54 | 8647 | return NULL; |
24f1e32c FW |
8648 | } |
8649 | ||
51676957 | 8650 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 8651 | { |
51676957 PZ |
8652 | int cpu; |
8653 | ||
8654 | for_each_possible_cpu(cpu) { | |
8655 | struct perf_cpu_context *cpuctx; | |
8656 | ||
8657 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8658 | ||
3f1f3320 PZ |
8659 | if (cpuctx->unique_pmu == old_pmu) |
8660 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
8661 | } |
8662 | } | |
8663 | ||
8664 | static void free_pmu_context(struct pmu *pmu) | |
8665 | { | |
8666 | struct pmu *i; | |
f5ffe02e | 8667 | |
8dc85d54 | 8668 | mutex_lock(&pmus_lock); |
0475f9ea | 8669 | /* |
8dc85d54 | 8670 | * Like a real lame refcount. |
0475f9ea | 8671 | */ |
51676957 PZ |
8672 | list_for_each_entry(i, &pmus, entry) { |
8673 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
8674 | update_pmu_context(i, pmu); | |
8dc85d54 | 8675 | goto out; |
51676957 | 8676 | } |
8dc85d54 | 8677 | } |
d6d020e9 | 8678 | |
51676957 | 8679 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
8680 | out: |
8681 | mutex_unlock(&pmus_lock); | |
24f1e32c | 8682 | } |
6e855cd4 AS |
8683 | |
8684 | /* | |
8685 | * Let userspace know that this PMU supports address range filtering: | |
8686 | */ | |
8687 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8688 | struct device_attribute *attr, | |
8689 | char *page) | |
8690 | { | |
8691 | struct pmu *pmu = dev_get_drvdata(dev); | |
8692 | ||
8693 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8694 | } | |
8695 | DEVICE_ATTR_RO(nr_addr_filters); | |
8696 | ||
2e80a82a | 8697 | static struct idr pmu_idr; |
d6d020e9 | 8698 | |
abe43400 PZ |
8699 | static ssize_t |
8700 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8701 | { | |
8702 | struct pmu *pmu = dev_get_drvdata(dev); | |
8703 | ||
8704 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8705 | } | |
90826ca7 | 8706 | static DEVICE_ATTR_RO(type); |
abe43400 | 8707 | |
62b85639 SE |
8708 | static ssize_t |
8709 | perf_event_mux_interval_ms_show(struct device *dev, | |
8710 | struct device_attribute *attr, | |
8711 | char *page) | |
8712 | { | |
8713 | struct pmu *pmu = dev_get_drvdata(dev); | |
8714 | ||
8715 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8716 | } | |
8717 | ||
272325c4 PZ |
8718 | static DEFINE_MUTEX(mux_interval_mutex); |
8719 | ||
62b85639 SE |
8720 | static ssize_t |
8721 | perf_event_mux_interval_ms_store(struct device *dev, | |
8722 | struct device_attribute *attr, | |
8723 | const char *buf, size_t count) | |
8724 | { | |
8725 | struct pmu *pmu = dev_get_drvdata(dev); | |
8726 | int timer, cpu, ret; | |
8727 | ||
8728 | ret = kstrtoint(buf, 0, &timer); | |
8729 | if (ret) | |
8730 | return ret; | |
8731 | ||
8732 | if (timer < 1) | |
8733 | return -EINVAL; | |
8734 | ||
8735 | /* same value, noting to do */ | |
8736 | if (timer == pmu->hrtimer_interval_ms) | |
8737 | return count; | |
8738 | ||
272325c4 | 8739 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8740 | pmu->hrtimer_interval_ms = timer; |
8741 | ||
8742 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8743 | get_online_cpus(); |
8744 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8745 | struct perf_cpu_context *cpuctx; |
8746 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8747 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8748 | ||
272325c4 PZ |
8749 | cpu_function_call(cpu, |
8750 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8751 | } |
272325c4 PZ |
8752 | put_online_cpus(); |
8753 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8754 | |
8755 | return count; | |
8756 | } | |
90826ca7 | 8757 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8758 | |
90826ca7 GKH |
8759 | static struct attribute *pmu_dev_attrs[] = { |
8760 | &dev_attr_type.attr, | |
8761 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8762 | NULL, | |
abe43400 | 8763 | }; |
90826ca7 | 8764 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8765 | |
8766 | static int pmu_bus_running; | |
8767 | static struct bus_type pmu_bus = { | |
8768 | .name = "event_source", | |
90826ca7 | 8769 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8770 | }; |
8771 | ||
8772 | static void pmu_dev_release(struct device *dev) | |
8773 | { | |
8774 | kfree(dev); | |
8775 | } | |
8776 | ||
8777 | static int pmu_dev_alloc(struct pmu *pmu) | |
8778 | { | |
8779 | int ret = -ENOMEM; | |
8780 | ||
8781 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8782 | if (!pmu->dev) | |
8783 | goto out; | |
8784 | ||
0c9d42ed | 8785 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8786 | device_initialize(pmu->dev); |
8787 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8788 | if (ret) | |
8789 | goto free_dev; | |
8790 | ||
8791 | dev_set_drvdata(pmu->dev, pmu); | |
8792 | pmu->dev->bus = &pmu_bus; | |
8793 | pmu->dev->release = pmu_dev_release; | |
8794 | ret = device_add(pmu->dev); | |
8795 | if (ret) | |
8796 | goto free_dev; | |
8797 | ||
6e855cd4 AS |
8798 | /* For PMUs with address filters, throw in an extra attribute: */ |
8799 | if (pmu->nr_addr_filters) | |
8800 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8801 | ||
8802 | if (ret) | |
8803 | goto del_dev; | |
8804 | ||
abe43400 PZ |
8805 | out: |
8806 | return ret; | |
8807 | ||
6e855cd4 AS |
8808 | del_dev: |
8809 | device_del(pmu->dev); | |
8810 | ||
abe43400 PZ |
8811 | free_dev: |
8812 | put_device(pmu->dev); | |
8813 | goto out; | |
8814 | } | |
8815 | ||
547e9fd7 | 8816 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8817 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8818 | |
03d8e80b | 8819 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 8820 | { |
108b02cf | 8821 | int cpu, ret; |
24f1e32c | 8822 | |
b0a873eb | 8823 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
8824 | ret = -ENOMEM; |
8825 | pmu->pmu_disable_count = alloc_percpu(int); | |
8826 | if (!pmu->pmu_disable_count) | |
8827 | goto unlock; | |
f29ac756 | 8828 | |
2e80a82a PZ |
8829 | pmu->type = -1; |
8830 | if (!name) | |
8831 | goto skip_type; | |
8832 | pmu->name = name; | |
8833 | ||
8834 | if (type < 0) { | |
0e9c3be2 TH |
8835 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
8836 | if (type < 0) { | |
8837 | ret = type; | |
2e80a82a PZ |
8838 | goto free_pdc; |
8839 | } | |
8840 | } | |
8841 | pmu->type = type; | |
8842 | ||
abe43400 PZ |
8843 | if (pmu_bus_running) { |
8844 | ret = pmu_dev_alloc(pmu); | |
8845 | if (ret) | |
8846 | goto free_idr; | |
8847 | } | |
8848 | ||
2e80a82a | 8849 | skip_type: |
26657848 PZ |
8850 | if (pmu->task_ctx_nr == perf_hw_context) { |
8851 | static int hw_context_taken = 0; | |
8852 | ||
5101ef20 MR |
8853 | /* |
8854 | * Other than systems with heterogeneous CPUs, it never makes | |
8855 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
8856 | * uncore must use perf_invalid_context. | |
8857 | */ | |
8858 | if (WARN_ON_ONCE(hw_context_taken && | |
8859 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
8860 | pmu->task_ctx_nr = perf_invalid_context; |
8861 | ||
8862 | hw_context_taken = 1; | |
8863 | } | |
8864 | ||
8dc85d54 PZ |
8865 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
8866 | if (pmu->pmu_cpu_context) | |
8867 | goto got_cpu_context; | |
f29ac756 | 8868 | |
c4814202 | 8869 | ret = -ENOMEM; |
108b02cf PZ |
8870 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
8871 | if (!pmu->pmu_cpu_context) | |
abe43400 | 8872 | goto free_dev; |
f344011c | 8873 | |
108b02cf PZ |
8874 | for_each_possible_cpu(cpu) { |
8875 | struct perf_cpu_context *cpuctx; | |
8876 | ||
8877 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 8878 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 8879 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 8880 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 8881 | cpuctx->ctx.pmu = pmu; |
9e630205 | 8882 | |
272325c4 | 8883 | __perf_mux_hrtimer_init(cpuctx, cpu); |
9e630205 | 8884 | |
3f1f3320 | 8885 | cpuctx->unique_pmu = pmu; |
108b02cf | 8886 | } |
76e1d904 | 8887 | |
8dc85d54 | 8888 | got_cpu_context: |
ad5133b7 PZ |
8889 | if (!pmu->start_txn) { |
8890 | if (pmu->pmu_enable) { | |
8891 | /* | |
8892 | * If we have pmu_enable/pmu_disable calls, install | |
8893 | * transaction stubs that use that to try and batch | |
8894 | * hardware accesses. | |
8895 | */ | |
8896 | pmu->start_txn = perf_pmu_start_txn; | |
8897 | pmu->commit_txn = perf_pmu_commit_txn; | |
8898 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
8899 | } else { | |
fbbe0701 | 8900 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
8901 | pmu->commit_txn = perf_pmu_nop_int; |
8902 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 8903 | } |
5c92d124 | 8904 | } |
15dbf27c | 8905 | |
ad5133b7 PZ |
8906 | if (!pmu->pmu_enable) { |
8907 | pmu->pmu_enable = perf_pmu_nop_void; | |
8908 | pmu->pmu_disable = perf_pmu_nop_void; | |
8909 | } | |
8910 | ||
35edc2a5 PZ |
8911 | if (!pmu->event_idx) |
8912 | pmu->event_idx = perf_event_idx_default; | |
8913 | ||
b0a873eb | 8914 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 8915 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
8916 | ret = 0; |
8917 | unlock: | |
b0a873eb PZ |
8918 | mutex_unlock(&pmus_lock); |
8919 | ||
33696fc0 | 8920 | return ret; |
108b02cf | 8921 | |
abe43400 PZ |
8922 | free_dev: |
8923 | device_del(pmu->dev); | |
8924 | put_device(pmu->dev); | |
8925 | ||
2e80a82a PZ |
8926 | free_idr: |
8927 | if (pmu->type >= PERF_TYPE_MAX) | |
8928 | idr_remove(&pmu_idr, pmu->type); | |
8929 | ||
108b02cf PZ |
8930 | free_pdc: |
8931 | free_percpu(pmu->pmu_disable_count); | |
8932 | goto unlock; | |
f29ac756 | 8933 | } |
c464c76e | 8934 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 8935 | |
b0a873eb | 8936 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 8937 | { |
0933840a JO |
8938 | int remove_device; |
8939 | ||
b0a873eb | 8940 | mutex_lock(&pmus_lock); |
0933840a | 8941 | remove_device = pmu_bus_running; |
b0a873eb PZ |
8942 | list_del_rcu(&pmu->entry); |
8943 | mutex_unlock(&pmus_lock); | |
5c92d124 | 8944 | |
0475f9ea | 8945 | /* |
cde8e884 PZ |
8946 | * We dereference the pmu list under both SRCU and regular RCU, so |
8947 | * synchronize against both of those. | |
0475f9ea | 8948 | */ |
b0a873eb | 8949 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 8950 | synchronize_rcu(); |
d6d020e9 | 8951 | |
33696fc0 | 8952 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
8953 | if (pmu->type >= PERF_TYPE_MAX) |
8954 | idr_remove(&pmu_idr, pmu->type); | |
0933840a JO |
8955 | if (remove_device) { |
8956 | if (pmu->nr_addr_filters) | |
8957 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8958 | device_del(pmu->dev); | |
8959 | put_device(pmu->dev); | |
8960 | } | |
51676957 | 8961 | free_pmu_context(pmu); |
b0a873eb | 8962 | } |
c464c76e | 8963 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 8964 | |
cc34b98b MR |
8965 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
8966 | { | |
ccd41c86 | 8967 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
8968 | int ret; |
8969 | ||
8970 | if (!try_module_get(pmu->module)) | |
8971 | return -ENODEV; | |
ccd41c86 PZ |
8972 | |
8973 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
8974 | /* |
8975 | * This ctx->mutex can nest when we're called through | |
8976 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
8977 | */ | |
8978 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
8979 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
8980 | BUG_ON(!ctx); |
8981 | } | |
8982 | ||
cc34b98b MR |
8983 | event->pmu = pmu; |
8984 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
8985 | |
8986 | if (ctx) | |
8987 | perf_event_ctx_unlock(event->group_leader, ctx); | |
8988 | ||
cc34b98b MR |
8989 | if (ret) |
8990 | module_put(pmu->module); | |
8991 | ||
8992 | return ret; | |
8993 | } | |
8994 | ||
18ab2cd3 | 8995 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
8996 | { |
8997 | struct pmu *pmu = NULL; | |
8998 | int idx; | |
940c5b29 | 8999 | int ret; |
b0a873eb PZ |
9000 | |
9001 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
9002 | |
9003 | rcu_read_lock(); | |
9004 | pmu = idr_find(&pmu_idr, event->attr.type); | |
9005 | rcu_read_unlock(); | |
940c5b29 | 9006 | if (pmu) { |
cc34b98b | 9007 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
9008 | if (ret) |
9009 | pmu = ERR_PTR(ret); | |
2e80a82a | 9010 | goto unlock; |
940c5b29 | 9011 | } |
2e80a82a | 9012 | |
b0a873eb | 9013 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 9014 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 9015 | if (!ret) |
e5f4d339 | 9016 | goto unlock; |
76e1d904 | 9017 | |
b0a873eb PZ |
9018 | if (ret != -ENOENT) { |
9019 | pmu = ERR_PTR(ret); | |
e5f4d339 | 9020 | goto unlock; |
f344011c | 9021 | } |
5c92d124 | 9022 | } |
e5f4d339 PZ |
9023 | pmu = ERR_PTR(-ENOENT); |
9024 | unlock: | |
b0a873eb | 9025 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 9026 | |
4aeb0b42 | 9027 | return pmu; |
5c92d124 IM |
9028 | } |
9029 | ||
f2fb6bef KL |
9030 | static void attach_sb_event(struct perf_event *event) |
9031 | { | |
9032 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
9033 | ||
9034 | raw_spin_lock(&pel->lock); | |
9035 | list_add_rcu(&event->sb_list, &pel->list); | |
9036 | raw_spin_unlock(&pel->lock); | |
9037 | } | |
9038 | ||
aab5b71e PZ |
9039 | /* |
9040 | * We keep a list of all !task (and therefore per-cpu) events | |
9041 | * that need to receive side-band records. | |
9042 | * | |
9043 | * This avoids having to scan all the various PMU per-cpu contexts | |
9044 | * looking for them. | |
9045 | */ | |
f2fb6bef KL |
9046 | static void account_pmu_sb_event(struct perf_event *event) |
9047 | { | |
a4f144eb | 9048 | if (is_sb_event(event)) |
f2fb6bef KL |
9049 | attach_sb_event(event); |
9050 | } | |
9051 | ||
4beb31f3 FW |
9052 | static void account_event_cpu(struct perf_event *event, int cpu) |
9053 | { | |
9054 | if (event->parent) | |
9055 | return; | |
9056 | ||
4beb31f3 FW |
9057 | if (is_cgroup_event(event)) |
9058 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9059 | } | |
9060 | ||
555e0c1e FW |
9061 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9062 | static void account_freq_event_nohz(void) | |
9063 | { | |
9064 | #ifdef CONFIG_NO_HZ_FULL | |
9065 | /* Lock so we don't race with concurrent unaccount */ | |
9066 | spin_lock(&nr_freq_lock); | |
9067 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9068 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9069 | spin_unlock(&nr_freq_lock); | |
9070 | #endif | |
9071 | } | |
9072 | ||
9073 | static void account_freq_event(void) | |
9074 | { | |
9075 | if (tick_nohz_full_enabled()) | |
9076 | account_freq_event_nohz(); | |
9077 | else | |
9078 | atomic_inc(&nr_freq_events); | |
9079 | } | |
9080 | ||
9081 | ||
766d6c07 FW |
9082 | static void account_event(struct perf_event *event) |
9083 | { | |
25432ae9 PZ |
9084 | bool inc = false; |
9085 | ||
4beb31f3 FW |
9086 | if (event->parent) |
9087 | return; | |
9088 | ||
766d6c07 | 9089 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9090 | inc = true; |
766d6c07 FW |
9091 | if (event->attr.mmap || event->attr.mmap_data) |
9092 | atomic_inc(&nr_mmap_events); | |
9093 | if (event->attr.comm) | |
9094 | atomic_inc(&nr_comm_events); | |
9095 | if (event->attr.task) | |
9096 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9097 | if (event->attr.freq) |
9098 | account_freq_event(); | |
45ac1403 AH |
9099 | if (event->attr.context_switch) { |
9100 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9101 | inc = true; |
45ac1403 | 9102 | } |
4beb31f3 | 9103 | if (has_branch_stack(event)) |
25432ae9 | 9104 | inc = true; |
4beb31f3 | 9105 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9106 | inc = true; |
9107 | ||
9107c89e PZ |
9108 | if (inc) { |
9109 | if (atomic_inc_not_zero(&perf_sched_count)) | |
9110 | goto enabled; | |
9111 | ||
9112 | mutex_lock(&perf_sched_mutex); | |
9113 | if (!atomic_read(&perf_sched_count)) { | |
9114 | static_branch_enable(&perf_sched_events); | |
9115 | /* | |
9116 | * Guarantee that all CPUs observe they key change and | |
9117 | * call the perf scheduling hooks before proceeding to | |
9118 | * install events that need them. | |
9119 | */ | |
9120 | synchronize_sched(); | |
9121 | } | |
9122 | /* | |
9123 | * Now that we have waited for the sync_sched(), allow further | |
9124 | * increments to by-pass the mutex. | |
9125 | */ | |
9126 | atomic_inc(&perf_sched_count); | |
9127 | mutex_unlock(&perf_sched_mutex); | |
9128 | } | |
9129 | enabled: | |
4beb31f3 FW |
9130 | |
9131 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9132 | |
9133 | account_pmu_sb_event(event); | |
766d6c07 FW |
9134 | } |
9135 | ||
0793a61d | 9136 | /* |
cdd6c482 | 9137 | * Allocate and initialize a event structure |
0793a61d | 9138 | */ |
cdd6c482 | 9139 | static struct perf_event * |
c3f00c70 | 9140 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9141 | struct task_struct *task, |
9142 | struct perf_event *group_leader, | |
9143 | struct perf_event *parent_event, | |
4dc0da86 | 9144 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9145 | void *context, int cgroup_fd) |
0793a61d | 9146 | { |
51b0fe39 | 9147 | struct pmu *pmu; |
cdd6c482 IM |
9148 | struct perf_event *event; |
9149 | struct hw_perf_event *hwc; | |
90983b16 | 9150 | long err = -EINVAL; |
0793a61d | 9151 | |
66832eb4 ON |
9152 | if ((unsigned)cpu >= nr_cpu_ids) { |
9153 | if (!task || cpu != -1) | |
9154 | return ERR_PTR(-EINVAL); | |
9155 | } | |
9156 | ||
c3f00c70 | 9157 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9158 | if (!event) |
d5d2bc0d | 9159 | return ERR_PTR(-ENOMEM); |
0793a61d | 9160 | |
04289bb9 | 9161 | /* |
cdd6c482 | 9162 | * Single events are their own group leaders, with an |
04289bb9 IM |
9163 | * empty sibling list: |
9164 | */ | |
9165 | if (!group_leader) | |
cdd6c482 | 9166 | group_leader = event; |
04289bb9 | 9167 | |
cdd6c482 IM |
9168 | mutex_init(&event->child_mutex); |
9169 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9170 | |
cdd6c482 IM |
9171 | INIT_LIST_HEAD(&event->group_entry); |
9172 | INIT_LIST_HEAD(&event->event_entry); | |
9173 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 9174 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9175 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9176 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9177 | INIT_HLIST_NODE(&event->hlist_entry); |
9178 | ||
10c6db11 | 9179 | |
cdd6c482 | 9180 | init_waitqueue_head(&event->waitq); |
e360adbe | 9181 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9182 | |
cdd6c482 | 9183 | mutex_init(&event->mmap_mutex); |
375637bc | 9184 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9185 | |
a6fa941d | 9186 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9187 | event->cpu = cpu; |
9188 | event->attr = *attr; | |
9189 | event->group_leader = group_leader; | |
9190 | event->pmu = NULL; | |
cdd6c482 | 9191 | event->oncpu = -1; |
a96bbc16 | 9192 | |
cdd6c482 | 9193 | event->parent = parent_event; |
b84fbc9f | 9194 | |
17cf22c3 | 9195 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9196 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9197 | |
cdd6c482 | 9198 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9199 | |
d580ff86 PZ |
9200 | if (task) { |
9201 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9202 | /* |
50f16a8b PZ |
9203 | * XXX pmu::event_init needs to know what task to account to |
9204 | * and we cannot use the ctx information because we need the | |
9205 | * pmu before we get a ctx. | |
d580ff86 | 9206 | */ |
50f16a8b | 9207 | event->hw.target = task; |
d580ff86 PZ |
9208 | } |
9209 | ||
34f43927 PZ |
9210 | event->clock = &local_clock; |
9211 | if (parent_event) | |
9212 | event->clock = parent_event->clock; | |
9213 | ||
4dc0da86 | 9214 | if (!overflow_handler && parent_event) { |
b326e956 | 9215 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9216 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9217 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9218 | if (overflow_handler == bpf_overflow_handler) { |
9219 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9220 | ||
9221 | if (IS_ERR(prog)) { | |
9222 | err = PTR_ERR(prog); | |
9223 | goto err_ns; | |
9224 | } | |
9225 | event->prog = prog; | |
9226 | event->orig_overflow_handler = | |
9227 | parent_event->orig_overflow_handler; | |
9228 | } | |
9229 | #endif | |
4dc0da86 | 9230 | } |
66832eb4 | 9231 | |
1879445d WN |
9232 | if (overflow_handler) { |
9233 | event->overflow_handler = overflow_handler; | |
9234 | event->overflow_handler_context = context; | |
9ecda41a WN |
9235 | } else if (is_write_backward(event)){ |
9236 | event->overflow_handler = perf_event_output_backward; | |
9237 | event->overflow_handler_context = NULL; | |
1879445d | 9238 | } else { |
9ecda41a | 9239 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9240 | event->overflow_handler_context = NULL; |
9241 | } | |
97eaf530 | 9242 | |
0231bb53 | 9243 | perf_event__state_init(event); |
a86ed508 | 9244 | |
4aeb0b42 | 9245 | pmu = NULL; |
b8e83514 | 9246 | |
cdd6c482 | 9247 | hwc = &event->hw; |
bd2b5b12 | 9248 | hwc->sample_period = attr->sample_period; |
0d48696f | 9249 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9250 | hwc->sample_period = 1; |
eced1dfc | 9251 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9252 | |
e7850595 | 9253 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9254 | |
2023b359 | 9255 | /* |
cdd6c482 | 9256 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 9257 | */ |
3dab77fb | 9258 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 9259 | goto err_ns; |
a46a2300 YZ |
9260 | |
9261 | if (!has_branch_stack(event)) | |
9262 | event->attr.branch_sample_type = 0; | |
2023b359 | 9263 | |
79dff51e MF |
9264 | if (cgroup_fd != -1) { |
9265 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9266 | if (err) | |
9267 | goto err_ns; | |
9268 | } | |
9269 | ||
b0a873eb | 9270 | pmu = perf_init_event(event); |
4aeb0b42 | 9271 | if (!pmu) |
90983b16 FW |
9272 | goto err_ns; |
9273 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 9274 | err = PTR_ERR(pmu); |
90983b16 | 9275 | goto err_ns; |
621a01ea | 9276 | } |
d5d2bc0d | 9277 | |
bed5b25a AS |
9278 | err = exclusive_event_init(event); |
9279 | if (err) | |
9280 | goto err_pmu; | |
9281 | ||
375637bc AS |
9282 | if (has_addr_filter(event)) { |
9283 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9284 | sizeof(unsigned long), | |
9285 | GFP_KERNEL); | |
9286 | if (!event->addr_filters_offs) | |
9287 | goto err_per_task; | |
9288 | ||
9289 | /* force hw sync on the address filters */ | |
9290 | event->addr_filters_gen = 1; | |
9291 | } | |
9292 | ||
cdd6c482 | 9293 | if (!event->parent) { |
927c7a9e | 9294 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9295 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9296 | if (err) |
375637bc | 9297 | goto err_addr_filters; |
d010b332 | 9298 | } |
f344011c | 9299 | } |
9ee318a7 | 9300 | |
927a5570 AS |
9301 | /* symmetric to unaccount_event() in _free_event() */ |
9302 | account_event(event); | |
9303 | ||
cdd6c482 | 9304 | return event; |
90983b16 | 9305 | |
375637bc AS |
9306 | err_addr_filters: |
9307 | kfree(event->addr_filters_offs); | |
9308 | ||
bed5b25a AS |
9309 | err_per_task: |
9310 | exclusive_event_destroy(event); | |
9311 | ||
90983b16 FW |
9312 | err_pmu: |
9313 | if (event->destroy) | |
9314 | event->destroy(event); | |
c464c76e | 9315 | module_put(pmu->module); |
90983b16 | 9316 | err_ns: |
79dff51e MF |
9317 | if (is_cgroup_event(event)) |
9318 | perf_detach_cgroup(event); | |
90983b16 FW |
9319 | if (event->ns) |
9320 | put_pid_ns(event->ns); | |
9321 | kfree(event); | |
9322 | ||
9323 | return ERR_PTR(err); | |
0793a61d TG |
9324 | } |
9325 | ||
cdd6c482 IM |
9326 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9327 | struct perf_event_attr *attr) | |
974802ea | 9328 | { |
974802ea | 9329 | u32 size; |
cdf8073d | 9330 | int ret; |
974802ea PZ |
9331 | |
9332 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9333 | return -EFAULT; | |
9334 | ||
9335 | /* | |
9336 | * zero the full structure, so that a short copy will be nice. | |
9337 | */ | |
9338 | memset(attr, 0, sizeof(*attr)); | |
9339 | ||
9340 | ret = get_user(size, &uattr->size); | |
9341 | if (ret) | |
9342 | return ret; | |
9343 | ||
9344 | if (size > PAGE_SIZE) /* silly large */ | |
9345 | goto err_size; | |
9346 | ||
9347 | if (!size) /* abi compat */ | |
9348 | size = PERF_ATTR_SIZE_VER0; | |
9349 | ||
9350 | if (size < PERF_ATTR_SIZE_VER0) | |
9351 | goto err_size; | |
9352 | ||
9353 | /* | |
9354 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9355 | * ensure all the unknown bits are 0 - i.e. new |
9356 | * user-space does not rely on any kernel feature | |
9357 | * extensions we dont know about yet. | |
974802ea PZ |
9358 | */ |
9359 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9360 | unsigned char __user *addr; |
9361 | unsigned char __user *end; | |
9362 | unsigned char val; | |
974802ea | 9363 | |
cdf8073d IS |
9364 | addr = (void __user *)uattr + sizeof(*attr); |
9365 | end = (void __user *)uattr + size; | |
974802ea | 9366 | |
cdf8073d | 9367 | for (; addr < end; addr++) { |
974802ea PZ |
9368 | ret = get_user(val, addr); |
9369 | if (ret) | |
9370 | return ret; | |
9371 | if (val) | |
9372 | goto err_size; | |
9373 | } | |
b3e62e35 | 9374 | size = sizeof(*attr); |
974802ea PZ |
9375 | } |
9376 | ||
9377 | ret = copy_from_user(attr, uattr, size); | |
9378 | if (ret) | |
9379 | return -EFAULT; | |
9380 | ||
cd757645 | 9381 | if (attr->__reserved_1) |
974802ea PZ |
9382 | return -EINVAL; |
9383 | ||
9384 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9385 | return -EINVAL; | |
9386 | ||
9387 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9388 | return -EINVAL; | |
9389 | ||
bce38cd5 SE |
9390 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9391 | u64 mask = attr->branch_sample_type; | |
9392 | ||
9393 | /* only using defined bits */ | |
9394 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9395 | return -EINVAL; | |
9396 | ||
9397 | /* at least one branch bit must be set */ | |
9398 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9399 | return -EINVAL; | |
9400 | ||
bce38cd5 SE |
9401 | /* propagate priv level, when not set for branch */ |
9402 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9403 | ||
9404 | /* exclude_kernel checked on syscall entry */ | |
9405 | if (!attr->exclude_kernel) | |
9406 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9407 | ||
9408 | if (!attr->exclude_user) | |
9409 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9410 | ||
9411 | if (!attr->exclude_hv) | |
9412 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9413 | /* | |
9414 | * adjust user setting (for HW filter setup) | |
9415 | */ | |
9416 | attr->branch_sample_type = mask; | |
9417 | } | |
e712209a SE |
9418 | /* privileged levels capture (kernel, hv): check permissions */ |
9419 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9420 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9421 | return -EACCES; | |
bce38cd5 | 9422 | } |
4018994f | 9423 | |
c5ebcedb | 9424 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9425 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9426 | if (ret) |
9427 | return ret; | |
9428 | } | |
9429 | ||
9430 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9431 | if (!arch_perf_have_user_stack_dump()) | |
9432 | return -ENOSYS; | |
9433 | ||
9434 | /* | |
9435 | * We have __u32 type for the size, but so far | |
9436 | * we can only use __u16 as maximum due to the | |
9437 | * __u16 sample size limit. | |
9438 | */ | |
9439 | if (attr->sample_stack_user >= USHRT_MAX) | |
9440 | ret = -EINVAL; | |
9441 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9442 | ret = -EINVAL; | |
9443 | } | |
4018994f | 9444 | |
60e2364e SE |
9445 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9446 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9447 | out: |
9448 | return ret; | |
9449 | ||
9450 | err_size: | |
9451 | put_user(sizeof(*attr), &uattr->size); | |
9452 | ret = -E2BIG; | |
9453 | goto out; | |
9454 | } | |
9455 | ||
ac9721f3 PZ |
9456 | static int |
9457 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9458 | { |
b69cf536 | 9459 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9460 | int ret = -EINVAL; |
9461 | ||
ac9721f3 | 9462 | if (!output_event) |
a4be7c27 PZ |
9463 | goto set; |
9464 | ||
ac9721f3 PZ |
9465 | /* don't allow circular references */ |
9466 | if (event == output_event) | |
a4be7c27 PZ |
9467 | goto out; |
9468 | ||
0f139300 PZ |
9469 | /* |
9470 | * Don't allow cross-cpu buffers | |
9471 | */ | |
9472 | if (output_event->cpu != event->cpu) | |
9473 | goto out; | |
9474 | ||
9475 | /* | |
76369139 | 9476 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9477 | */ |
9478 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9479 | goto out; | |
9480 | ||
34f43927 PZ |
9481 | /* |
9482 | * Mixing clocks in the same buffer is trouble you don't need. | |
9483 | */ | |
9484 | if (output_event->clock != event->clock) | |
9485 | goto out; | |
9486 | ||
9ecda41a WN |
9487 | /* |
9488 | * Either writing ring buffer from beginning or from end. | |
9489 | * Mixing is not allowed. | |
9490 | */ | |
9491 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9492 | goto out; | |
9493 | ||
45bfb2e5 PZ |
9494 | /* |
9495 | * If both events generate aux data, they must be on the same PMU | |
9496 | */ | |
9497 | if (has_aux(event) && has_aux(output_event) && | |
9498 | event->pmu != output_event->pmu) | |
9499 | goto out; | |
9500 | ||
a4be7c27 | 9501 | set: |
cdd6c482 | 9502 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9503 | /* Can't redirect output if we've got an active mmap() */ |
9504 | if (atomic_read(&event->mmap_count)) | |
9505 | goto unlock; | |
a4be7c27 | 9506 | |
ac9721f3 | 9507 | if (output_event) { |
76369139 FW |
9508 | /* get the rb we want to redirect to */ |
9509 | rb = ring_buffer_get(output_event); | |
9510 | if (!rb) | |
ac9721f3 | 9511 | goto unlock; |
a4be7c27 PZ |
9512 | } |
9513 | ||
b69cf536 | 9514 | ring_buffer_attach(event, rb); |
9bb5d40c | 9515 | |
a4be7c27 | 9516 | ret = 0; |
ac9721f3 PZ |
9517 | unlock: |
9518 | mutex_unlock(&event->mmap_mutex); | |
9519 | ||
a4be7c27 | 9520 | out: |
a4be7c27 PZ |
9521 | return ret; |
9522 | } | |
9523 | ||
f63a8daa PZ |
9524 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9525 | { | |
9526 | if (b < a) | |
9527 | swap(a, b); | |
9528 | ||
9529 | mutex_lock(a); | |
9530 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9531 | } | |
9532 | ||
34f43927 PZ |
9533 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9534 | { | |
9535 | bool nmi_safe = false; | |
9536 | ||
9537 | switch (clk_id) { | |
9538 | case CLOCK_MONOTONIC: | |
9539 | event->clock = &ktime_get_mono_fast_ns; | |
9540 | nmi_safe = true; | |
9541 | break; | |
9542 | ||
9543 | case CLOCK_MONOTONIC_RAW: | |
9544 | event->clock = &ktime_get_raw_fast_ns; | |
9545 | nmi_safe = true; | |
9546 | break; | |
9547 | ||
9548 | case CLOCK_REALTIME: | |
9549 | event->clock = &ktime_get_real_ns; | |
9550 | break; | |
9551 | ||
9552 | case CLOCK_BOOTTIME: | |
9553 | event->clock = &ktime_get_boot_ns; | |
9554 | break; | |
9555 | ||
9556 | case CLOCK_TAI: | |
9557 | event->clock = &ktime_get_tai_ns; | |
9558 | break; | |
9559 | ||
9560 | default: | |
9561 | return -EINVAL; | |
9562 | } | |
9563 | ||
9564 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9565 | return -EINVAL; | |
9566 | ||
9567 | return 0; | |
9568 | } | |
9569 | ||
321027c1 PZ |
9570 | /* |
9571 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
9572 | * mutexes. | |
9573 | */ | |
9574 | static struct perf_event_context * | |
9575 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
9576 | struct perf_event_context *ctx) | |
9577 | { | |
9578 | struct perf_event_context *gctx; | |
9579 | ||
9580 | again: | |
9581 | rcu_read_lock(); | |
9582 | gctx = READ_ONCE(group_leader->ctx); | |
9583 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
9584 | rcu_read_unlock(); | |
9585 | goto again; | |
9586 | } | |
9587 | rcu_read_unlock(); | |
9588 | ||
9589 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
9590 | ||
9591 | if (group_leader->ctx != gctx) { | |
9592 | mutex_unlock(&ctx->mutex); | |
9593 | mutex_unlock(&gctx->mutex); | |
9594 | put_ctx(gctx); | |
9595 | goto again; | |
9596 | } | |
9597 | ||
9598 | return gctx; | |
9599 | } | |
9600 | ||
0793a61d | 9601 | /** |
cdd6c482 | 9602 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9603 | * |
cdd6c482 | 9604 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9605 | * @pid: target pid |
9f66a381 | 9606 | * @cpu: target cpu |
cdd6c482 | 9607 | * @group_fd: group leader event fd |
0793a61d | 9608 | */ |
cdd6c482 IM |
9609 | SYSCALL_DEFINE5(perf_event_open, |
9610 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9611 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9612 | { |
b04243ef PZ |
9613 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9614 | struct perf_event *event, *sibling; | |
cdd6c482 | 9615 | struct perf_event_attr attr; |
f63a8daa | 9616 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9617 | struct file *event_file = NULL; |
2903ff01 | 9618 | struct fd group = {NULL, 0}; |
38a81da2 | 9619 | struct task_struct *task = NULL; |
89a1e187 | 9620 | struct pmu *pmu; |
ea635c64 | 9621 | int event_fd; |
b04243ef | 9622 | int move_group = 0; |
dc86cabe | 9623 | int err; |
a21b0b35 | 9624 | int f_flags = O_RDWR; |
79dff51e | 9625 | int cgroup_fd = -1; |
0793a61d | 9626 | |
2743a5b0 | 9627 | /* for future expandability... */ |
e5d1367f | 9628 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9629 | return -EINVAL; |
9630 | ||
dc86cabe IM |
9631 | err = perf_copy_attr(attr_uptr, &attr); |
9632 | if (err) | |
9633 | return err; | |
eab656ae | 9634 | |
0764771d PZ |
9635 | if (!attr.exclude_kernel) { |
9636 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9637 | return -EACCES; | |
9638 | } | |
9639 | ||
df58ab24 | 9640 | if (attr.freq) { |
cdd6c482 | 9641 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9642 | return -EINVAL; |
0819b2e3 PZ |
9643 | } else { |
9644 | if (attr.sample_period & (1ULL << 63)) | |
9645 | return -EINVAL; | |
df58ab24 PZ |
9646 | } |
9647 | ||
97c79a38 ACM |
9648 | if (!attr.sample_max_stack) |
9649 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9650 | ||
e5d1367f SE |
9651 | /* |
9652 | * In cgroup mode, the pid argument is used to pass the fd | |
9653 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9654 | * designates the cpu on which to monitor threads from that | |
9655 | * cgroup. | |
9656 | */ | |
9657 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9658 | return -EINVAL; | |
9659 | ||
a21b0b35 YD |
9660 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9661 | f_flags |= O_CLOEXEC; | |
9662 | ||
9663 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9664 | if (event_fd < 0) |
9665 | return event_fd; | |
9666 | ||
ac9721f3 | 9667 | if (group_fd != -1) { |
2903ff01 AV |
9668 | err = perf_fget_light(group_fd, &group); |
9669 | if (err) | |
d14b12d7 | 9670 | goto err_fd; |
2903ff01 | 9671 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9672 | if (flags & PERF_FLAG_FD_OUTPUT) |
9673 | output_event = group_leader; | |
9674 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9675 | group_leader = NULL; | |
9676 | } | |
9677 | ||
e5d1367f | 9678 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9679 | task = find_lively_task_by_vpid(pid); |
9680 | if (IS_ERR(task)) { | |
9681 | err = PTR_ERR(task); | |
9682 | goto err_group_fd; | |
9683 | } | |
9684 | } | |
9685 | ||
1f4ee503 PZ |
9686 | if (task && group_leader && |
9687 | group_leader->attr.inherit != attr.inherit) { | |
9688 | err = -EINVAL; | |
9689 | goto err_task; | |
9690 | } | |
9691 | ||
fbfc623f YZ |
9692 | get_online_cpus(); |
9693 | ||
79c9ce57 PZ |
9694 | if (task) { |
9695 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9696 | if (err) | |
9697 | goto err_cpus; | |
9698 | ||
9699 | /* | |
9700 | * Reuse ptrace permission checks for now. | |
9701 | * | |
9702 | * We must hold cred_guard_mutex across this and any potential | |
9703 | * perf_install_in_context() call for this new event to | |
9704 | * serialize against exec() altering our credentials (and the | |
9705 | * perf_event_exit_task() that could imply). | |
9706 | */ | |
9707 | err = -EACCES; | |
9708 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9709 | goto err_cred; | |
9710 | } | |
9711 | ||
79dff51e MF |
9712 | if (flags & PERF_FLAG_PID_CGROUP) |
9713 | cgroup_fd = pid; | |
9714 | ||
4dc0da86 | 9715 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9716 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9717 | if (IS_ERR(event)) { |
9718 | err = PTR_ERR(event); | |
79c9ce57 | 9719 | goto err_cred; |
d14b12d7 SE |
9720 | } |
9721 | ||
53b25335 VW |
9722 | if (is_sampling_event(event)) { |
9723 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9724 | err = -EOPNOTSUPP; |
53b25335 VW |
9725 | goto err_alloc; |
9726 | } | |
9727 | } | |
9728 | ||
89a1e187 PZ |
9729 | /* |
9730 | * Special case software events and allow them to be part of | |
9731 | * any hardware group. | |
9732 | */ | |
9733 | pmu = event->pmu; | |
b04243ef | 9734 | |
34f43927 PZ |
9735 | if (attr.use_clockid) { |
9736 | err = perf_event_set_clock(event, attr.clockid); | |
9737 | if (err) | |
9738 | goto err_alloc; | |
9739 | } | |
9740 | ||
4ff6a8de DCC |
9741 | if (pmu->task_ctx_nr == perf_sw_context) |
9742 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
9743 | ||
b04243ef PZ |
9744 | if (group_leader && |
9745 | (is_software_event(event) != is_software_event(group_leader))) { | |
9746 | if (is_software_event(event)) { | |
9747 | /* | |
9748 | * If event and group_leader are not both a software | |
9749 | * event, and event is, then group leader is not. | |
9750 | * | |
9751 | * Allow the addition of software events to !software | |
9752 | * groups, this is safe because software events never | |
9753 | * fail to schedule. | |
9754 | */ | |
9755 | pmu = group_leader->pmu; | |
9756 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 9757 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
9758 | /* |
9759 | * In case the group is a pure software group, and we | |
9760 | * try to add a hardware event, move the whole group to | |
9761 | * the hardware context. | |
9762 | */ | |
9763 | move_group = 1; | |
9764 | } | |
9765 | } | |
89a1e187 PZ |
9766 | |
9767 | /* | |
9768 | * Get the target context (task or percpu): | |
9769 | */ | |
4af57ef2 | 9770 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9771 | if (IS_ERR(ctx)) { |
9772 | err = PTR_ERR(ctx); | |
c6be5a5c | 9773 | goto err_alloc; |
89a1e187 PZ |
9774 | } |
9775 | ||
bed5b25a AS |
9776 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9777 | err = -EBUSY; | |
9778 | goto err_context; | |
9779 | } | |
9780 | ||
ccff286d | 9781 | /* |
cdd6c482 | 9782 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9783 | */ |
ac9721f3 | 9784 | if (group_leader) { |
dc86cabe | 9785 | err = -EINVAL; |
04289bb9 | 9786 | |
04289bb9 | 9787 | /* |
ccff286d IM |
9788 | * Do not allow a recursive hierarchy (this new sibling |
9789 | * becoming part of another group-sibling): | |
9790 | */ | |
9791 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9792 | goto err_context; |
34f43927 PZ |
9793 | |
9794 | /* All events in a group should have the same clock */ | |
9795 | if (group_leader->clock != event->clock) | |
9796 | goto err_context; | |
9797 | ||
ccff286d IM |
9798 | /* |
9799 | * Do not allow to attach to a group in a different | |
9800 | * task or CPU context: | |
04289bb9 | 9801 | */ |
b04243ef | 9802 | if (move_group) { |
c3c87e77 PZ |
9803 | /* |
9804 | * Make sure we're both on the same task, or both | |
9805 | * per-cpu events. | |
9806 | */ | |
9807 | if (group_leader->ctx->task != ctx->task) | |
9808 | goto err_context; | |
9809 | ||
9810 | /* | |
9811 | * Make sure we're both events for the same CPU; | |
9812 | * grouping events for different CPUs is broken; since | |
9813 | * you can never concurrently schedule them anyhow. | |
9814 | */ | |
9815 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
9816 | goto err_context; |
9817 | } else { | |
9818 | if (group_leader->ctx != ctx) | |
9819 | goto err_context; | |
9820 | } | |
9821 | ||
3b6f9e5c PM |
9822 | /* |
9823 | * Only a group leader can be exclusive or pinned | |
9824 | */ | |
0d48696f | 9825 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 9826 | goto err_context; |
ac9721f3 PZ |
9827 | } |
9828 | ||
9829 | if (output_event) { | |
9830 | err = perf_event_set_output(event, output_event); | |
9831 | if (err) | |
c3f00c70 | 9832 | goto err_context; |
ac9721f3 | 9833 | } |
0793a61d | 9834 | |
a21b0b35 YD |
9835 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
9836 | f_flags); | |
ea635c64 AV |
9837 | if (IS_ERR(event_file)) { |
9838 | err = PTR_ERR(event_file); | |
201c2f85 | 9839 | event_file = NULL; |
c3f00c70 | 9840 | goto err_context; |
ea635c64 | 9841 | } |
9b51f66d | 9842 | |
b04243ef | 9843 | if (move_group) { |
321027c1 PZ |
9844 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
9845 | ||
84c4e620 PZ |
9846 | if (gctx->task == TASK_TOMBSTONE) { |
9847 | err = -ESRCH; | |
9848 | goto err_locked; | |
9849 | } | |
321027c1 PZ |
9850 | |
9851 | /* | |
9852 | * Check if we raced against another sys_perf_event_open() call | |
9853 | * moving the software group underneath us. | |
9854 | */ | |
9855 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
9856 | /* | |
9857 | * If someone moved the group out from under us, check | |
9858 | * if this new event wound up on the same ctx, if so | |
9859 | * its the regular !move_group case, otherwise fail. | |
9860 | */ | |
9861 | if (gctx != ctx) { | |
9862 | err = -EINVAL; | |
9863 | goto err_locked; | |
9864 | } else { | |
9865 | perf_event_ctx_unlock(group_leader, gctx); | |
9866 | move_group = 0; | |
9867 | } | |
9868 | } | |
f55fc2a5 PZ |
9869 | } else { |
9870 | mutex_lock(&ctx->mutex); | |
9871 | } | |
9872 | ||
84c4e620 PZ |
9873 | if (ctx->task == TASK_TOMBSTONE) { |
9874 | err = -ESRCH; | |
9875 | goto err_locked; | |
9876 | } | |
9877 | ||
a723968c PZ |
9878 | if (!perf_event_validate_size(event)) { |
9879 | err = -E2BIG; | |
9880 | goto err_locked; | |
9881 | } | |
9882 | ||
f55fc2a5 PZ |
9883 | /* |
9884 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
9885 | * because we need to serialize with concurrent event creation. | |
9886 | */ | |
9887 | if (!exclusive_event_installable(event, ctx)) { | |
9888 | /* exclusive and group stuff are assumed mutually exclusive */ | |
9889 | WARN_ON_ONCE(move_group); | |
f63a8daa | 9890 | |
f55fc2a5 PZ |
9891 | err = -EBUSY; |
9892 | goto err_locked; | |
9893 | } | |
f63a8daa | 9894 | |
f55fc2a5 PZ |
9895 | WARN_ON_ONCE(ctx->parent_ctx); |
9896 | ||
79c9ce57 PZ |
9897 | /* |
9898 | * This is the point on no return; we cannot fail hereafter. This is | |
9899 | * where we start modifying current state. | |
9900 | */ | |
9901 | ||
f55fc2a5 | 9902 | if (move_group) { |
f63a8daa PZ |
9903 | /* |
9904 | * See perf_event_ctx_lock() for comments on the details | |
9905 | * of swizzling perf_event::ctx. | |
9906 | */ | |
45a0e07a | 9907 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 9908 | |
b04243ef PZ |
9909 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9910 | group_entry) { | |
45a0e07a | 9911 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
9912 | put_ctx(gctx); |
9913 | } | |
b04243ef | 9914 | |
f63a8daa PZ |
9915 | /* |
9916 | * Wait for everybody to stop referencing the events through | |
9917 | * the old lists, before installing it on new lists. | |
9918 | */ | |
0cda4c02 | 9919 | synchronize_rcu(); |
f63a8daa | 9920 | |
8f95b435 PZI |
9921 | /* |
9922 | * Install the group siblings before the group leader. | |
9923 | * | |
9924 | * Because a group leader will try and install the entire group | |
9925 | * (through the sibling list, which is still in-tact), we can | |
9926 | * end up with siblings installed in the wrong context. | |
9927 | * | |
9928 | * By installing siblings first we NO-OP because they're not | |
9929 | * reachable through the group lists. | |
9930 | */ | |
b04243ef PZ |
9931 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9932 | group_entry) { | |
8f95b435 | 9933 | perf_event__state_init(sibling); |
9fc81d87 | 9934 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
9935 | get_ctx(ctx); |
9936 | } | |
8f95b435 PZI |
9937 | |
9938 | /* | |
9939 | * Removing from the context ends up with disabled | |
9940 | * event. What we want here is event in the initial | |
9941 | * startup state, ready to be add into new context. | |
9942 | */ | |
9943 | perf_event__state_init(group_leader); | |
9944 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
9945 | get_ctx(ctx); | |
b04243ef | 9946 | |
f55fc2a5 PZ |
9947 | /* |
9948 | * Now that all events are installed in @ctx, nothing | |
9949 | * references @gctx anymore, so drop the last reference we have | |
9950 | * on it. | |
9951 | */ | |
9952 | put_ctx(gctx); | |
bed5b25a AS |
9953 | } |
9954 | ||
f73e22ab PZ |
9955 | /* |
9956 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
9957 | * that we're serialized against further additions and before | |
9958 | * perf_install_in_context() which is the point the event is active and | |
9959 | * can use these values. | |
9960 | */ | |
9961 | perf_event__header_size(event); | |
9962 | perf_event__id_header_size(event); | |
9963 | ||
78cd2c74 PZ |
9964 | event->owner = current; |
9965 | ||
e2d37cd2 | 9966 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 9967 | perf_unpin_context(ctx); |
f63a8daa | 9968 | |
f55fc2a5 | 9969 | if (move_group) |
321027c1 | 9970 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 9971 | mutex_unlock(&ctx->mutex); |
9b51f66d | 9972 | |
79c9ce57 PZ |
9973 | if (task) { |
9974 | mutex_unlock(&task->signal->cred_guard_mutex); | |
9975 | put_task_struct(task); | |
9976 | } | |
9977 | ||
fbfc623f YZ |
9978 | put_online_cpus(); |
9979 | ||
cdd6c482 IM |
9980 | mutex_lock(¤t->perf_event_mutex); |
9981 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
9982 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 9983 | |
8a49542c PZ |
9984 | /* |
9985 | * Drop the reference on the group_event after placing the | |
9986 | * new event on the sibling_list. This ensures destruction | |
9987 | * of the group leader will find the pointer to itself in | |
9988 | * perf_group_detach(). | |
9989 | */ | |
2903ff01 | 9990 | fdput(group); |
ea635c64 AV |
9991 | fd_install(event_fd, event_file); |
9992 | return event_fd; | |
0793a61d | 9993 | |
f55fc2a5 PZ |
9994 | err_locked: |
9995 | if (move_group) | |
321027c1 | 9996 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
9997 | mutex_unlock(&ctx->mutex); |
9998 | /* err_file: */ | |
9999 | fput(event_file); | |
c3f00c70 | 10000 | err_context: |
fe4b04fa | 10001 | perf_unpin_context(ctx); |
ea635c64 | 10002 | put_ctx(ctx); |
c6be5a5c | 10003 | err_alloc: |
13005627 PZ |
10004 | /* |
10005 | * If event_file is set, the fput() above will have called ->release() | |
10006 | * and that will take care of freeing the event. | |
10007 | */ | |
10008 | if (!event_file) | |
10009 | free_event(event); | |
79c9ce57 PZ |
10010 | err_cred: |
10011 | if (task) | |
10012 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 10013 | err_cpus: |
fbfc623f | 10014 | put_online_cpus(); |
1f4ee503 | 10015 | err_task: |
e7d0bc04 PZ |
10016 | if (task) |
10017 | put_task_struct(task); | |
89a1e187 | 10018 | err_group_fd: |
2903ff01 | 10019 | fdput(group); |
ea635c64 AV |
10020 | err_fd: |
10021 | put_unused_fd(event_fd); | |
dc86cabe | 10022 | return err; |
0793a61d TG |
10023 | } |
10024 | ||
fb0459d7 AV |
10025 | /** |
10026 | * perf_event_create_kernel_counter | |
10027 | * | |
10028 | * @attr: attributes of the counter to create | |
10029 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 10030 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
10031 | */ |
10032 | struct perf_event * | |
10033 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 10034 | struct task_struct *task, |
4dc0da86 AK |
10035 | perf_overflow_handler_t overflow_handler, |
10036 | void *context) | |
fb0459d7 | 10037 | { |
fb0459d7 | 10038 | struct perf_event_context *ctx; |
c3f00c70 | 10039 | struct perf_event *event; |
fb0459d7 | 10040 | int err; |
d859e29f | 10041 | |
fb0459d7 AV |
10042 | /* |
10043 | * Get the target context (task or percpu): | |
10044 | */ | |
d859e29f | 10045 | |
4dc0da86 | 10046 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10047 | overflow_handler, context, -1); |
c3f00c70 PZ |
10048 | if (IS_ERR(event)) { |
10049 | err = PTR_ERR(event); | |
10050 | goto err; | |
10051 | } | |
d859e29f | 10052 | |
f8697762 | 10053 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10054 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10055 | |
4af57ef2 | 10056 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10057 | if (IS_ERR(ctx)) { |
10058 | err = PTR_ERR(ctx); | |
c3f00c70 | 10059 | goto err_free; |
d859e29f | 10060 | } |
fb0459d7 | 10061 | |
fb0459d7 AV |
10062 | WARN_ON_ONCE(ctx->parent_ctx); |
10063 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10064 | if (ctx->task == TASK_TOMBSTONE) { |
10065 | err = -ESRCH; | |
10066 | goto err_unlock; | |
10067 | } | |
10068 | ||
bed5b25a | 10069 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10070 | err = -EBUSY; |
84c4e620 | 10071 | goto err_unlock; |
bed5b25a AS |
10072 | } |
10073 | ||
fb0459d7 | 10074 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 10075 | perf_unpin_context(ctx); |
fb0459d7 AV |
10076 | mutex_unlock(&ctx->mutex); |
10077 | ||
fb0459d7 AV |
10078 | return event; |
10079 | ||
84c4e620 PZ |
10080 | err_unlock: |
10081 | mutex_unlock(&ctx->mutex); | |
10082 | perf_unpin_context(ctx); | |
10083 | put_ctx(ctx); | |
c3f00c70 PZ |
10084 | err_free: |
10085 | free_event(event); | |
10086 | err: | |
c6567f64 | 10087 | return ERR_PTR(err); |
9b51f66d | 10088 | } |
fb0459d7 | 10089 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10090 | |
0cda4c02 YZ |
10091 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10092 | { | |
10093 | struct perf_event_context *src_ctx; | |
10094 | struct perf_event_context *dst_ctx; | |
10095 | struct perf_event *event, *tmp; | |
10096 | LIST_HEAD(events); | |
10097 | ||
10098 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10099 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10100 | ||
f63a8daa PZ |
10101 | /* |
10102 | * See perf_event_ctx_lock() for comments on the details | |
10103 | * of swizzling perf_event::ctx. | |
10104 | */ | |
10105 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10106 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10107 | event_entry) { | |
45a0e07a | 10108 | perf_remove_from_context(event, 0); |
9a545de0 | 10109 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10110 | put_ctx(src_ctx); |
9886167d | 10111 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10112 | } |
0cda4c02 | 10113 | |
8f95b435 PZI |
10114 | /* |
10115 | * Wait for the events to quiesce before re-instating them. | |
10116 | */ | |
0cda4c02 YZ |
10117 | synchronize_rcu(); |
10118 | ||
8f95b435 PZI |
10119 | /* |
10120 | * Re-instate events in 2 passes. | |
10121 | * | |
10122 | * Skip over group leaders and only install siblings on this first | |
10123 | * pass, siblings will not get enabled without a leader, however a | |
10124 | * leader will enable its siblings, even if those are still on the old | |
10125 | * context. | |
10126 | */ | |
10127 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10128 | if (event->group_leader == event) | |
10129 | continue; | |
10130 | ||
10131 | list_del(&event->migrate_entry); | |
10132 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10133 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10134 | account_event_cpu(event, dst_cpu); | |
10135 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10136 | get_ctx(dst_ctx); | |
10137 | } | |
10138 | ||
10139 | /* | |
10140 | * Once all the siblings are setup properly, install the group leaders | |
10141 | * to make it go. | |
10142 | */ | |
9886167d PZ |
10143 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10144 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10145 | if (event->state >= PERF_EVENT_STATE_OFF) |
10146 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10147 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10148 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10149 | get_ctx(dst_ctx); | |
10150 | } | |
10151 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10152 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10153 | } |
10154 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10155 | ||
cdd6c482 | 10156 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10157 | struct task_struct *child) |
d859e29f | 10158 | { |
cdd6c482 | 10159 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10160 | u64 child_val; |
d859e29f | 10161 | |
cdd6c482 IM |
10162 | if (child_event->attr.inherit_stat) |
10163 | perf_event_read_event(child_event, child); | |
38b200d6 | 10164 | |
b5e58793 | 10165 | child_val = perf_event_count(child_event); |
d859e29f PM |
10166 | |
10167 | /* | |
10168 | * Add back the child's count to the parent's count: | |
10169 | */ | |
a6e6dea6 | 10170 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10171 | atomic64_add(child_event->total_time_enabled, |
10172 | &parent_event->child_total_time_enabled); | |
10173 | atomic64_add(child_event->total_time_running, | |
10174 | &parent_event->child_total_time_running); | |
d859e29f PM |
10175 | } |
10176 | ||
9b51f66d | 10177 | static void |
8ba289b8 PZ |
10178 | perf_event_exit_event(struct perf_event *child_event, |
10179 | struct perf_event_context *child_ctx, | |
10180 | struct task_struct *child) | |
9b51f66d | 10181 | { |
8ba289b8 PZ |
10182 | struct perf_event *parent_event = child_event->parent; |
10183 | ||
1903d50c PZ |
10184 | /* |
10185 | * Do not destroy the 'original' grouping; because of the context | |
10186 | * switch optimization the original events could've ended up in a | |
10187 | * random child task. | |
10188 | * | |
10189 | * If we were to destroy the original group, all group related | |
10190 | * operations would cease to function properly after this random | |
10191 | * child dies. | |
10192 | * | |
10193 | * Do destroy all inherited groups, we don't care about those | |
10194 | * and being thorough is better. | |
10195 | */ | |
32132a3d PZ |
10196 | raw_spin_lock_irq(&child_ctx->lock); |
10197 | WARN_ON_ONCE(child_ctx->is_active); | |
10198 | ||
8ba289b8 | 10199 | if (parent_event) |
32132a3d PZ |
10200 | perf_group_detach(child_event); |
10201 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 10202 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 10203 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10204 | |
9b51f66d | 10205 | /* |
8ba289b8 | 10206 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10207 | */ |
8ba289b8 | 10208 | if (!parent_event) { |
179033b3 | 10209 | perf_event_wakeup(child_event); |
8ba289b8 | 10210 | return; |
4bcf349a | 10211 | } |
8ba289b8 PZ |
10212 | /* |
10213 | * Child events can be cleaned up. | |
10214 | */ | |
10215 | ||
10216 | sync_child_event(child_event, child); | |
10217 | ||
10218 | /* | |
10219 | * Remove this event from the parent's list | |
10220 | */ | |
10221 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10222 | mutex_lock(&parent_event->child_mutex); | |
10223 | list_del_init(&child_event->child_list); | |
10224 | mutex_unlock(&parent_event->child_mutex); | |
10225 | ||
10226 | /* | |
10227 | * Kick perf_poll() for is_event_hup(). | |
10228 | */ | |
10229 | perf_event_wakeup(parent_event); | |
10230 | free_event(child_event); | |
10231 | put_event(parent_event); | |
9b51f66d IM |
10232 | } |
10233 | ||
8dc85d54 | 10234 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10235 | { |
211de6eb | 10236 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10237 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10238 | |
10239 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10240 | |
6a3351b6 | 10241 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10242 | if (!child_ctx) |
9b51f66d IM |
10243 | return; |
10244 | ||
ad3a37de | 10245 | /* |
6a3351b6 PZ |
10246 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10247 | * ctx::mutex over the entire thing. This serializes against almost | |
10248 | * everything that wants to access the ctx. | |
10249 | * | |
10250 | * The exception is sys_perf_event_open() / | |
10251 | * perf_event_create_kernel_count() which does find_get_context() | |
10252 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10253 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10254 | */ |
6a3351b6 | 10255 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10256 | |
10257 | /* | |
6a3351b6 PZ |
10258 | * In a single ctx::lock section, de-schedule the events and detach the |
10259 | * context from the task such that we cannot ever get it scheduled back | |
10260 | * in. | |
c93f7669 | 10261 | */ |
6a3351b6 | 10262 | raw_spin_lock_irq(&child_ctx->lock); |
63b6da39 | 10263 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx); |
4a1c0f26 | 10264 | |
71a851b4 | 10265 | /* |
63b6da39 PZ |
10266 | * Now that the context is inactive, destroy the task <-> ctx relation |
10267 | * and mark the context dead. | |
71a851b4 | 10268 | */ |
63b6da39 PZ |
10269 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10270 | put_ctx(child_ctx); /* cannot be last */ | |
10271 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10272 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10273 | |
211de6eb | 10274 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10275 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10276 | |
211de6eb PZ |
10277 | if (clone_ctx) |
10278 | put_ctx(clone_ctx); | |
4a1c0f26 | 10279 | |
9f498cc5 | 10280 | /* |
cdd6c482 IM |
10281 | * Report the task dead after unscheduling the events so that we |
10282 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10283 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10284 | */ |
cdd6c482 | 10285 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10286 | |
ebf905fc | 10287 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10288 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10289 | |
a63eaf34 PM |
10290 | mutex_unlock(&child_ctx->mutex); |
10291 | ||
10292 | put_ctx(child_ctx); | |
9b51f66d IM |
10293 | } |
10294 | ||
8dc85d54 PZ |
10295 | /* |
10296 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10297 | * |
10298 | * Can be called with cred_guard_mutex held when called from | |
10299 | * install_exec_creds(). | |
8dc85d54 PZ |
10300 | */ |
10301 | void perf_event_exit_task(struct task_struct *child) | |
10302 | { | |
8882135b | 10303 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10304 | int ctxn; |
10305 | ||
8882135b PZ |
10306 | mutex_lock(&child->perf_event_mutex); |
10307 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10308 | owner_entry) { | |
10309 | list_del_init(&event->owner_entry); | |
10310 | ||
10311 | /* | |
10312 | * Ensure the list deletion is visible before we clear | |
10313 | * the owner, closes a race against perf_release() where | |
10314 | * we need to serialize on the owner->perf_event_mutex. | |
10315 | */ | |
f47c02c0 | 10316 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10317 | } |
10318 | mutex_unlock(&child->perf_event_mutex); | |
10319 | ||
8dc85d54 PZ |
10320 | for_each_task_context_nr(ctxn) |
10321 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10322 | |
10323 | /* | |
10324 | * The perf_event_exit_task_context calls perf_event_task | |
10325 | * with child's task_ctx, which generates EXIT events for | |
10326 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10327 | * At this point we need to send EXIT events to cpu contexts. | |
10328 | */ | |
10329 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10330 | } |
10331 | ||
889ff015 FW |
10332 | static void perf_free_event(struct perf_event *event, |
10333 | struct perf_event_context *ctx) | |
10334 | { | |
10335 | struct perf_event *parent = event->parent; | |
10336 | ||
10337 | if (WARN_ON_ONCE(!parent)) | |
10338 | return; | |
10339 | ||
10340 | mutex_lock(&parent->child_mutex); | |
10341 | list_del_init(&event->child_list); | |
10342 | mutex_unlock(&parent->child_mutex); | |
10343 | ||
a6fa941d | 10344 | put_event(parent); |
889ff015 | 10345 | |
652884fe | 10346 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10347 | perf_group_detach(event); |
889ff015 | 10348 | list_del_event(event, ctx); |
652884fe | 10349 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10350 | free_event(event); |
10351 | } | |
10352 | ||
bbbee908 | 10353 | /* |
652884fe | 10354 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10355 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10356 | * |
10357 | * Not all locks are strictly required, but take them anyway to be nice and | |
10358 | * help out with the lockdep assertions. | |
bbbee908 | 10359 | */ |
cdd6c482 | 10360 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10361 | { |
8dc85d54 | 10362 | struct perf_event_context *ctx; |
cdd6c482 | 10363 | struct perf_event *event, *tmp; |
8dc85d54 | 10364 | int ctxn; |
bbbee908 | 10365 | |
8dc85d54 PZ |
10366 | for_each_task_context_nr(ctxn) { |
10367 | ctx = task->perf_event_ctxp[ctxn]; | |
10368 | if (!ctx) | |
10369 | continue; | |
bbbee908 | 10370 | |
8dc85d54 | 10371 | mutex_lock(&ctx->mutex); |
bbbee908 | 10372 | again: |
8dc85d54 PZ |
10373 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
10374 | group_entry) | |
10375 | perf_free_event(event, ctx); | |
bbbee908 | 10376 | |
8dc85d54 PZ |
10377 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
10378 | group_entry) | |
10379 | perf_free_event(event, ctx); | |
bbbee908 | 10380 | |
8dc85d54 PZ |
10381 | if (!list_empty(&ctx->pinned_groups) || |
10382 | !list_empty(&ctx->flexible_groups)) | |
10383 | goto again; | |
bbbee908 | 10384 | |
8dc85d54 | 10385 | mutex_unlock(&ctx->mutex); |
bbbee908 | 10386 | |
8dc85d54 PZ |
10387 | put_ctx(ctx); |
10388 | } | |
889ff015 FW |
10389 | } |
10390 | ||
4e231c79 PZ |
10391 | void perf_event_delayed_put(struct task_struct *task) |
10392 | { | |
10393 | int ctxn; | |
10394 | ||
10395 | for_each_task_context_nr(ctxn) | |
10396 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10397 | } | |
10398 | ||
e03e7ee3 | 10399 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10400 | { |
e03e7ee3 | 10401 | struct file *file; |
ffe8690c | 10402 | |
e03e7ee3 AS |
10403 | file = fget_raw(fd); |
10404 | if (!file) | |
10405 | return ERR_PTR(-EBADF); | |
ffe8690c | 10406 | |
e03e7ee3 AS |
10407 | if (file->f_op != &perf_fops) { |
10408 | fput(file); | |
10409 | return ERR_PTR(-EBADF); | |
10410 | } | |
ffe8690c | 10411 | |
e03e7ee3 | 10412 | return file; |
ffe8690c KX |
10413 | } |
10414 | ||
10415 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10416 | { | |
10417 | if (!event) | |
10418 | return ERR_PTR(-EINVAL); | |
10419 | ||
10420 | return &event->attr; | |
10421 | } | |
10422 | ||
97dee4f3 PZ |
10423 | /* |
10424 | * inherit a event from parent task to child task: | |
10425 | */ | |
10426 | static struct perf_event * | |
10427 | inherit_event(struct perf_event *parent_event, | |
10428 | struct task_struct *parent, | |
10429 | struct perf_event_context *parent_ctx, | |
10430 | struct task_struct *child, | |
10431 | struct perf_event *group_leader, | |
10432 | struct perf_event_context *child_ctx) | |
10433 | { | |
1929def9 | 10434 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10435 | struct perf_event *child_event; |
cee010ec | 10436 | unsigned long flags; |
97dee4f3 PZ |
10437 | |
10438 | /* | |
10439 | * Instead of creating recursive hierarchies of events, | |
10440 | * we link inherited events back to the original parent, | |
10441 | * which has a filp for sure, which we use as the reference | |
10442 | * count: | |
10443 | */ | |
10444 | if (parent_event->parent) | |
10445 | parent_event = parent_event->parent; | |
10446 | ||
10447 | child_event = perf_event_alloc(&parent_event->attr, | |
10448 | parent_event->cpu, | |
d580ff86 | 10449 | child, |
97dee4f3 | 10450 | group_leader, parent_event, |
79dff51e | 10451 | NULL, NULL, -1); |
97dee4f3 PZ |
10452 | if (IS_ERR(child_event)) |
10453 | return child_event; | |
a6fa941d | 10454 | |
c6e5b732 PZ |
10455 | /* |
10456 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10457 | * must be under the same lock in order to serialize against | |
10458 | * perf_event_release_kernel(), such that either we must observe | |
10459 | * is_orphaned_event() or they will observe us on the child_list. | |
10460 | */ | |
10461 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10462 | if (is_orphaned_event(parent_event) || |
10463 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10464 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10465 | free_event(child_event); |
10466 | return NULL; | |
10467 | } | |
10468 | ||
97dee4f3 PZ |
10469 | get_ctx(child_ctx); |
10470 | ||
10471 | /* | |
10472 | * Make the child state follow the state of the parent event, | |
10473 | * not its attr.disabled bit. We hold the parent's mutex, | |
10474 | * so we won't race with perf_event_{en, dis}able_family. | |
10475 | */ | |
1929def9 | 10476 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10477 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10478 | else | |
10479 | child_event->state = PERF_EVENT_STATE_OFF; | |
10480 | ||
10481 | if (parent_event->attr.freq) { | |
10482 | u64 sample_period = parent_event->hw.sample_period; | |
10483 | struct hw_perf_event *hwc = &child_event->hw; | |
10484 | ||
10485 | hwc->sample_period = sample_period; | |
10486 | hwc->last_period = sample_period; | |
10487 | ||
10488 | local64_set(&hwc->period_left, sample_period); | |
10489 | } | |
10490 | ||
10491 | child_event->ctx = child_ctx; | |
10492 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10493 | child_event->overflow_handler_context |
10494 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10495 | |
614b6780 TG |
10496 | /* |
10497 | * Precalculate sample_data sizes | |
10498 | */ | |
10499 | perf_event__header_size(child_event); | |
6844c09d | 10500 | perf_event__id_header_size(child_event); |
614b6780 | 10501 | |
97dee4f3 PZ |
10502 | /* |
10503 | * Link it up in the child's context: | |
10504 | */ | |
cee010ec | 10505 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10506 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10507 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10508 | |
97dee4f3 PZ |
10509 | /* |
10510 | * Link this into the parent event's child list | |
10511 | */ | |
97dee4f3 PZ |
10512 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10513 | mutex_unlock(&parent_event->child_mutex); | |
10514 | ||
10515 | return child_event; | |
10516 | } | |
10517 | ||
10518 | static int inherit_group(struct perf_event *parent_event, | |
10519 | struct task_struct *parent, | |
10520 | struct perf_event_context *parent_ctx, | |
10521 | struct task_struct *child, | |
10522 | struct perf_event_context *child_ctx) | |
10523 | { | |
10524 | struct perf_event *leader; | |
10525 | struct perf_event *sub; | |
10526 | struct perf_event *child_ctr; | |
10527 | ||
10528 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10529 | child, NULL, child_ctx); | |
10530 | if (IS_ERR(leader)) | |
10531 | return PTR_ERR(leader); | |
10532 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
10533 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10534 | child, leader, child_ctx); | |
10535 | if (IS_ERR(child_ctr)) | |
10536 | return PTR_ERR(child_ctr); | |
10537 | } | |
10538 | return 0; | |
889ff015 FW |
10539 | } |
10540 | ||
10541 | static int | |
10542 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10543 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10544 | struct task_struct *child, int ctxn, |
889ff015 FW |
10545 | int *inherited_all) |
10546 | { | |
10547 | int ret; | |
8dc85d54 | 10548 | struct perf_event_context *child_ctx; |
889ff015 FW |
10549 | |
10550 | if (!event->attr.inherit) { | |
10551 | *inherited_all = 0; | |
10552 | return 0; | |
bbbee908 PZ |
10553 | } |
10554 | ||
fe4b04fa | 10555 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10556 | if (!child_ctx) { |
10557 | /* | |
10558 | * This is executed from the parent task context, so | |
10559 | * inherit events that have been marked for cloning. | |
10560 | * First allocate and initialize a context for the | |
10561 | * child. | |
10562 | */ | |
bbbee908 | 10563 | |
734df5ab | 10564 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10565 | if (!child_ctx) |
10566 | return -ENOMEM; | |
bbbee908 | 10567 | |
8dc85d54 | 10568 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10569 | } |
10570 | ||
10571 | ret = inherit_group(event, parent, parent_ctx, | |
10572 | child, child_ctx); | |
10573 | ||
10574 | if (ret) | |
10575 | *inherited_all = 0; | |
10576 | ||
10577 | return ret; | |
bbbee908 PZ |
10578 | } |
10579 | ||
9b51f66d | 10580 | /* |
cdd6c482 | 10581 | * Initialize the perf_event context in task_struct |
9b51f66d | 10582 | */ |
985c8dcb | 10583 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10584 | { |
889ff015 | 10585 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10586 | struct perf_event_context *cloned_ctx; |
10587 | struct perf_event *event; | |
9b51f66d | 10588 | struct task_struct *parent = current; |
564c2b21 | 10589 | int inherited_all = 1; |
dddd3379 | 10590 | unsigned long flags; |
6ab423e0 | 10591 | int ret = 0; |
9b51f66d | 10592 | |
8dc85d54 | 10593 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10594 | return 0; |
10595 | ||
ad3a37de | 10596 | /* |
25346b93 PM |
10597 | * If the parent's context is a clone, pin it so it won't get |
10598 | * swapped under us. | |
ad3a37de | 10599 | */ |
8dc85d54 | 10600 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10601 | if (!parent_ctx) |
10602 | return 0; | |
25346b93 | 10603 | |
ad3a37de PM |
10604 | /* |
10605 | * No need to check if parent_ctx != NULL here; since we saw | |
10606 | * it non-NULL earlier, the only reason for it to become NULL | |
10607 | * is if we exit, and since we're currently in the middle of | |
10608 | * a fork we can't be exiting at the same time. | |
10609 | */ | |
ad3a37de | 10610 | |
9b51f66d IM |
10611 | /* |
10612 | * Lock the parent list. No need to lock the child - not PID | |
10613 | * hashed yet and not running, so nobody can access it. | |
10614 | */ | |
d859e29f | 10615 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10616 | |
10617 | /* | |
10618 | * We dont have to disable NMIs - we are only looking at | |
10619 | * the list, not manipulating it: | |
10620 | */ | |
889ff015 | 10621 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10622 | ret = inherit_task_group(event, parent, parent_ctx, |
10623 | child, ctxn, &inherited_all); | |
889ff015 FW |
10624 | if (ret) |
10625 | break; | |
10626 | } | |
b93f7978 | 10627 | |
dddd3379 TG |
10628 | /* |
10629 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10630 | * to allocations, but we need to prevent rotation because | |
10631 | * rotate_ctx() will change the list from interrupt context. | |
10632 | */ | |
10633 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10634 | parent_ctx->rotate_disable = 1; | |
10635 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10636 | ||
889ff015 | 10637 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10638 | ret = inherit_task_group(event, parent, parent_ctx, |
10639 | child, ctxn, &inherited_all); | |
889ff015 | 10640 | if (ret) |
9b51f66d | 10641 | break; |
564c2b21 PM |
10642 | } |
10643 | ||
dddd3379 TG |
10644 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10645 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10646 | |
8dc85d54 | 10647 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10648 | |
05cbaa28 | 10649 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10650 | /* |
10651 | * Mark the child context as a clone of the parent | |
10652 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10653 | * |
10654 | * Note that if the parent is a clone, the holding of | |
10655 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10656 | */ |
c5ed5145 | 10657 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10658 | if (cloned_ctx) { |
10659 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10660 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10661 | } else { |
10662 | child_ctx->parent_ctx = parent_ctx; | |
10663 | child_ctx->parent_gen = parent_ctx->generation; | |
10664 | } | |
10665 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10666 | } |
10667 | ||
c5ed5145 | 10668 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 10669 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10670 | |
25346b93 | 10671 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10672 | put_ctx(parent_ctx); |
ad3a37de | 10673 | |
6ab423e0 | 10674 | return ret; |
9b51f66d IM |
10675 | } |
10676 | ||
8dc85d54 PZ |
10677 | /* |
10678 | * Initialize the perf_event context in task_struct | |
10679 | */ | |
10680 | int perf_event_init_task(struct task_struct *child) | |
10681 | { | |
10682 | int ctxn, ret; | |
10683 | ||
8550d7cb ON |
10684 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10685 | mutex_init(&child->perf_event_mutex); | |
10686 | INIT_LIST_HEAD(&child->perf_event_list); | |
10687 | ||
8dc85d54 PZ |
10688 | for_each_task_context_nr(ctxn) { |
10689 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10690 | if (ret) { |
10691 | perf_event_free_task(child); | |
8dc85d54 | 10692 | return ret; |
6c72e350 | 10693 | } |
8dc85d54 PZ |
10694 | } |
10695 | ||
10696 | return 0; | |
10697 | } | |
10698 | ||
220b140b PM |
10699 | static void __init perf_event_init_all_cpus(void) |
10700 | { | |
b28ab83c | 10701 | struct swevent_htable *swhash; |
220b140b | 10702 | int cpu; |
220b140b PM |
10703 | |
10704 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10705 | swhash = &per_cpu(swevent_htable, cpu); |
10706 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10707 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10708 | |
10709 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10710 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 PZ |
10711 | |
10712 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); | |
220b140b PM |
10713 | } |
10714 | } | |
10715 | ||
00e16c3d | 10716 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10717 | { |
108b02cf | 10718 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10719 | |
b28ab83c | 10720 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10721 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10722 | struct swevent_hlist *hlist; |
10723 | ||
b28ab83c PZ |
10724 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10725 | WARN_ON(!hlist); | |
10726 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10727 | } |
b28ab83c | 10728 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10729 | return 0; |
0793a61d TG |
10730 | } |
10731 | ||
2965faa5 | 10732 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10733 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10734 | { |
108b02cf | 10735 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10736 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10737 | struct perf_event *event; | |
0793a61d | 10738 | |
fae3fde6 PZ |
10739 | raw_spin_lock(&ctx->lock); |
10740 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10741 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10742 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10743 | } |
108b02cf PZ |
10744 | |
10745 | static void perf_event_exit_cpu_context(int cpu) | |
10746 | { | |
10747 | struct perf_event_context *ctx; | |
10748 | struct pmu *pmu; | |
10749 | int idx; | |
10750 | ||
10751 | idx = srcu_read_lock(&pmus_srcu); | |
10752 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10753 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10754 | |
10755 | mutex_lock(&ctx->mutex); | |
10756 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10757 | mutex_unlock(&ctx->mutex); | |
10758 | } | |
10759 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10760 | } |
00e16c3d TG |
10761 | #else |
10762 | ||
10763 | static void perf_event_exit_cpu_context(int cpu) { } | |
10764 | ||
10765 | #endif | |
108b02cf | 10766 | |
00e16c3d | 10767 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10768 | { |
e3703f8c | 10769 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10770 | return 0; |
0793a61d | 10771 | } |
0793a61d | 10772 | |
c277443c PZ |
10773 | static int |
10774 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10775 | { | |
10776 | int cpu; | |
10777 | ||
10778 | for_each_online_cpu(cpu) | |
10779 | perf_event_exit_cpu(cpu); | |
10780 | ||
10781 | return NOTIFY_OK; | |
10782 | } | |
10783 | ||
10784 | /* | |
10785 | * Run the perf reboot notifier at the very last possible moment so that | |
10786 | * the generic watchdog code runs as long as possible. | |
10787 | */ | |
10788 | static struct notifier_block perf_reboot_notifier = { | |
10789 | .notifier_call = perf_reboot, | |
10790 | .priority = INT_MIN, | |
10791 | }; | |
10792 | ||
cdd6c482 | 10793 | void __init perf_event_init(void) |
0793a61d | 10794 | { |
3c502e7a JW |
10795 | int ret; |
10796 | ||
2e80a82a PZ |
10797 | idr_init(&pmu_idr); |
10798 | ||
220b140b | 10799 | perf_event_init_all_cpus(); |
b0a873eb | 10800 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
10801 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
10802 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
10803 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 10804 | perf_tp_register(); |
00e16c3d | 10805 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 10806 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
10807 | |
10808 | ret = init_hw_breakpoint(); | |
10809 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 10810 | |
b01c3a00 JO |
10811 | /* |
10812 | * Build time assertion that we keep the data_head at the intended | |
10813 | * location. IOW, validation we got the __reserved[] size right. | |
10814 | */ | |
10815 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
10816 | != 1024); | |
0793a61d | 10817 | } |
abe43400 | 10818 | |
fd979c01 CS |
10819 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
10820 | char *page) | |
10821 | { | |
10822 | struct perf_pmu_events_attr *pmu_attr = | |
10823 | container_of(attr, struct perf_pmu_events_attr, attr); | |
10824 | ||
10825 | if (pmu_attr->event_str) | |
10826 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
10827 | ||
10828 | return 0; | |
10829 | } | |
675965b0 | 10830 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 10831 | |
abe43400 PZ |
10832 | static int __init perf_event_sysfs_init(void) |
10833 | { | |
10834 | struct pmu *pmu; | |
10835 | int ret; | |
10836 | ||
10837 | mutex_lock(&pmus_lock); | |
10838 | ||
10839 | ret = bus_register(&pmu_bus); | |
10840 | if (ret) | |
10841 | goto unlock; | |
10842 | ||
10843 | list_for_each_entry(pmu, &pmus, entry) { | |
10844 | if (!pmu->name || pmu->type < 0) | |
10845 | continue; | |
10846 | ||
10847 | ret = pmu_dev_alloc(pmu); | |
10848 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
10849 | } | |
10850 | pmu_bus_running = 1; | |
10851 | ret = 0; | |
10852 | ||
10853 | unlock: | |
10854 | mutex_unlock(&pmus_lock); | |
10855 | ||
10856 | return ret; | |
10857 | } | |
10858 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
10859 | |
10860 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
10861 | static struct cgroup_subsys_state * |
10862 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
10863 | { |
10864 | struct perf_cgroup *jc; | |
e5d1367f | 10865 | |
1b15d055 | 10866 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
10867 | if (!jc) |
10868 | return ERR_PTR(-ENOMEM); | |
10869 | ||
e5d1367f SE |
10870 | jc->info = alloc_percpu(struct perf_cgroup_info); |
10871 | if (!jc->info) { | |
10872 | kfree(jc); | |
10873 | return ERR_PTR(-ENOMEM); | |
10874 | } | |
10875 | ||
e5d1367f SE |
10876 | return &jc->css; |
10877 | } | |
10878 | ||
eb95419b | 10879 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 10880 | { |
eb95419b TH |
10881 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
10882 | ||
e5d1367f SE |
10883 | free_percpu(jc->info); |
10884 | kfree(jc); | |
10885 | } | |
10886 | ||
10887 | static int __perf_cgroup_move(void *info) | |
10888 | { | |
10889 | struct task_struct *task = info; | |
ddaaf4e2 | 10890 | rcu_read_lock(); |
e5d1367f | 10891 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 10892 | rcu_read_unlock(); |
e5d1367f SE |
10893 | return 0; |
10894 | } | |
10895 | ||
1f7dd3e5 | 10896 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 10897 | { |
bb9d97b6 | 10898 | struct task_struct *task; |
1f7dd3e5 | 10899 | struct cgroup_subsys_state *css; |
bb9d97b6 | 10900 | |
1f7dd3e5 | 10901 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 10902 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
10903 | } |
10904 | ||
073219e9 | 10905 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
10906 | .css_alloc = perf_cgroup_css_alloc, |
10907 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 10908 | .attach = perf_cgroup_attach, |
e5d1367f SE |
10909 | }; |
10910 | #endif /* CONFIG_CGROUP_PERF */ |