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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); | |
905 | cpuctx->cgrp = add ? event->cgrp : NULL; | |
906 | } | |
907 | ||
e5d1367f SE |
908 | #else /* !CONFIG_CGROUP_PERF */ |
909 | ||
910 | static inline bool | |
911 | perf_cgroup_match(struct perf_event *event) | |
912 | { | |
913 | return true; | |
914 | } | |
915 | ||
916 | static inline void perf_detach_cgroup(struct perf_event *event) | |
917 | {} | |
918 | ||
919 | static inline int is_cgroup_event(struct perf_event *event) | |
920 | { | |
921 | return 0; | |
922 | } | |
923 | ||
924 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
925 | { | |
926 | return 0; | |
927 | } | |
928 | ||
929 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
930 | { | |
931 | } | |
932 | ||
933 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
934 | { | |
935 | } | |
936 | ||
a8d757ef SE |
937 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
938 | struct task_struct *next) | |
e5d1367f SE |
939 | { |
940 | } | |
941 | ||
a8d757ef SE |
942 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
943 | struct task_struct *task) | |
e5d1367f SE |
944 | { |
945 | } | |
946 | ||
947 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
948 | struct perf_event_attr *attr, | |
949 | struct perf_event *group_leader) | |
950 | { | |
951 | return -EINVAL; | |
952 | } | |
953 | ||
954 | static inline void | |
3f7cce3c SE |
955 | perf_cgroup_set_timestamp(struct task_struct *task, |
956 | struct perf_event_context *ctx) | |
e5d1367f SE |
957 | { |
958 | } | |
959 | ||
960 | void | |
961 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
962 | { | |
963 | } | |
964 | ||
965 | static inline void | |
966 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
967 | { | |
968 | } | |
969 | ||
970 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
971 | { | |
972 | return 0; | |
973 | } | |
974 | ||
975 | static inline void | |
976 | perf_cgroup_defer_enabled(struct perf_event *event) | |
977 | { | |
978 | } | |
979 | ||
980 | static inline void | |
981 | perf_cgroup_mark_enabled(struct perf_event *event, | |
982 | struct perf_event_context *ctx) | |
983 | { | |
984 | } | |
db4a8356 DCC |
985 | |
986 | static inline void | |
987 | list_update_cgroup_event(struct perf_event *event, | |
988 | struct perf_event_context *ctx, bool add) | |
989 | { | |
990 | } | |
991 | ||
e5d1367f SE |
992 | #endif |
993 | ||
9e630205 SE |
994 | /* |
995 | * set default to be dependent on timer tick just | |
996 | * like original code | |
997 | */ | |
998 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
999 | /* | |
1000 | * function must be called with interrupts disbled | |
1001 | */ | |
272325c4 | 1002 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1003 | { |
1004 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1005 | int rotations = 0; |
1006 | ||
1007 | WARN_ON(!irqs_disabled()); | |
1008 | ||
1009 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1010 | rotations = perf_rotate_context(cpuctx); |
1011 | ||
4cfafd30 PZ |
1012 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1013 | if (rotations) | |
9e630205 | 1014 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1015 | else |
1016 | cpuctx->hrtimer_active = 0; | |
1017 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1018 | |
4cfafd30 | 1019 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1020 | } |
1021 | ||
272325c4 | 1022 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1023 | { |
272325c4 | 1024 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1025 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1026 | u64 interval; |
9e630205 SE |
1027 | |
1028 | /* no multiplexing needed for SW PMU */ | |
1029 | if (pmu->task_ctx_nr == perf_sw_context) | |
1030 | return; | |
1031 | ||
62b85639 SE |
1032 | /* |
1033 | * check default is sane, if not set then force to | |
1034 | * default interval (1/tick) | |
1035 | */ | |
272325c4 PZ |
1036 | interval = pmu->hrtimer_interval_ms; |
1037 | if (interval < 1) | |
1038 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1039 | |
272325c4 | 1040 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1041 | |
4cfafd30 PZ |
1042 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1043 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1044 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1045 | } |
1046 | ||
272325c4 | 1047 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1048 | { |
272325c4 | 1049 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1050 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1051 | unsigned long flags; |
9e630205 SE |
1052 | |
1053 | /* not for SW PMU */ | |
1054 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1055 | return 0; |
9e630205 | 1056 | |
4cfafd30 PZ |
1057 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1058 | if (!cpuctx->hrtimer_active) { | |
1059 | cpuctx->hrtimer_active = 1; | |
1060 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1061 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1062 | } | |
1063 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1064 | |
272325c4 | 1065 | return 0; |
9e630205 SE |
1066 | } |
1067 | ||
33696fc0 | 1068 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1069 | { |
33696fc0 PZ |
1070 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1071 | if (!(*count)++) | |
1072 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1073 | } |
9e35ad38 | 1074 | |
33696fc0 | 1075 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1076 | { |
33696fc0 PZ |
1077 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1078 | if (!--(*count)) | |
1079 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1080 | } |
9e35ad38 | 1081 | |
2fde4f94 | 1082 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1083 | |
1084 | /* | |
2fde4f94 MR |
1085 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1086 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1087 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1088 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1089 | */ |
2fde4f94 | 1090 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1091 | { |
2fde4f94 | 1092 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1093 | |
e9d2b064 | 1094 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1095 | |
2fde4f94 MR |
1096 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1097 | ||
1098 | list_add(&ctx->active_ctx_list, head); | |
1099 | } | |
1100 | ||
1101 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1102 | { | |
1103 | WARN_ON(!irqs_disabled()); | |
1104 | ||
1105 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1106 | ||
1107 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1108 | } |
9e35ad38 | 1109 | |
cdd6c482 | 1110 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1111 | { |
e5289d4a | 1112 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1113 | } |
1114 | ||
4af57ef2 YZ |
1115 | static void free_ctx(struct rcu_head *head) |
1116 | { | |
1117 | struct perf_event_context *ctx; | |
1118 | ||
1119 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1120 | kfree(ctx->task_ctx_data); | |
1121 | kfree(ctx); | |
1122 | } | |
1123 | ||
cdd6c482 | 1124 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1125 | { |
564c2b21 PM |
1126 | if (atomic_dec_and_test(&ctx->refcount)) { |
1127 | if (ctx->parent_ctx) | |
1128 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1129 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1130 | put_task_struct(ctx->task); |
4af57ef2 | 1131 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1132 | } |
a63eaf34 PM |
1133 | } |
1134 | ||
f63a8daa PZ |
1135 | /* |
1136 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1137 | * perf_pmu_migrate_context() we need some magic. | |
1138 | * | |
1139 | * Those places that change perf_event::ctx will hold both | |
1140 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1141 | * | |
8b10c5e2 PZ |
1142 | * Lock ordering is by mutex address. There are two other sites where |
1143 | * perf_event_context::mutex nests and those are: | |
1144 | * | |
1145 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1146 | * perf_event_exit_event() |
1147 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1148 | * |
1149 | * - perf_event_init_context() [ parent, 0 ] | |
1150 | * inherit_task_group() | |
1151 | * inherit_group() | |
1152 | * inherit_event() | |
1153 | * perf_event_alloc() | |
1154 | * perf_init_event() | |
1155 | * perf_try_init_event() [ child , 1 ] | |
1156 | * | |
1157 | * While it appears there is an obvious deadlock here -- the parent and child | |
1158 | * nesting levels are inverted between the two. This is in fact safe because | |
1159 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1160 | * spawning task cannot (yet) exit. | |
1161 | * | |
1162 | * But remember that that these are parent<->child context relations, and | |
1163 | * migration does not affect children, therefore these two orderings should not | |
1164 | * interact. | |
f63a8daa PZ |
1165 | * |
1166 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1167 | * because the sys_perf_event_open() case will install a new event and break | |
1168 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1169 | * concerned with cpuctx and that doesn't have children. | |
1170 | * | |
1171 | * The places that change perf_event::ctx will issue: | |
1172 | * | |
1173 | * perf_remove_from_context(); | |
1174 | * synchronize_rcu(); | |
1175 | * perf_install_in_context(); | |
1176 | * | |
1177 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1178 | * quiesce the event, after which we can install it in the new location. This | |
1179 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1180 | * while in transit. Therefore all such accessors should also acquire | |
1181 | * perf_event_context::mutex to serialize against this. | |
1182 | * | |
1183 | * However; because event->ctx can change while we're waiting to acquire | |
1184 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1185 | * function. | |
1186 | * | |
1187 | * Lock order: | |
79c9ce57 | 1188 | * cred_guard_mutex |
f63a8daa PZ |
1189 | * task_struct::perf_event_mutex |
1190 | * perf_event_context::mutex | |
f63a8daa | 1191 | * perf_event::child_mutex; |
07c4a776 | 1192 | * perf_event_context::lock |
f63a8daa PZ |
1193 | * perf_event::mmap_mutex |
1194 | * mmap_sem | |
1195 | */ | |
a83fe28e PZ |
1196 | static struct perf_event_context * |
1197 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1198 | { |
1199 | struct perf_event_context *ctx; | |
1200 | ||
1201 | again: | |
1202 | rcu_read_lock(); | |
1203 | ctx = ACCESS_ONCE(event->ctx); | |
1204 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1205 | rcu_read_unlock(); | |
1206 | goto again; | |
1207 | } | |
1208 | rcu_read_unlock(); | |
1209 | ||
a83fe28e | 1210 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1211 | if (event->ctx != ctx) { |
1212 | mutex_unlock(&ctx->mutex); | |
1213 | put_ctx(ctx); | |
1214 | goto again; | |
1215 | } | |
1216 | ||
1217 | return ctx; | |
1218 | } | |
1219 | ||
a83fe28e PZ |
1220 | static inline struct perf_event_context * |
1221 | perf_event_ctx_lock(struct perf_event *event) | |
1222 | { | |
1223 | return perf_event_ctx_lock_nested(event, 0); | |
1224 | } | |
1225 | ||
f63a8daa PZ |
1226 | static void perf_event_ctx_unlock(struct perf_event *event, |
1227 | struct perf_event_context *ctx) | |
1228 | { | |
1229 | mutex_unlock(&ctx->mutex); | |
1230 | put_ctx(ctx); | |
1231 | } | |
1232 | ||
211de6eb PZ |
1233 | /* |
1234 | * This must be done under the ctx->lock, such as to serialize against | |
1235 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1236 | * calling scheduler related locks and ctx->lock nests inside those. | |
1237 | */ | |
1238 | static __must_check struct perf_event_context * | |
1239 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1240 | { |
211de6eb PZ |
1241 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1242 | ||
1243 | lockdep_assert_held(&ctx->lock); | |
1244 | ||
1245 | if (parent_ctx) | |
71a851b4 | 1246 | ctx->parent_ctx = NULL; |
5a3126d4 | 1247 | ctx->generation++; |
211de6eb PZ |
1248 | |
1249 | return parent_ctx; | |
71a851b4 PZ |
1250 | } |
1251 | ||
6844c09d ACM |
1252 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1253 | { | |
1254 | /* | |
1255 | * only top level events have the pid namespace they were created in | |
1256 | */ | |
1257 | if (event->parent) | |
1258 | event = event->parent; | |
1259 | ||
1260 | return task_tgid_nr_ns(p, event->ns); | |
1261 | } | |
1262 | ||
1263 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1264 | { | |
1265 | /* | |
1266 | * only top level events have the pid namespace they were created in | |
1267 | */ | |
1268 | if (event->parent) | |
1269 | event = event->parent; | |
1270 | ||
1271 | return task_pid_nr_ns(p, event->ns); | |
1272 | } | |
1273 | ||
7f453c24 | 1274 | /* |
cdd6c482 | 1275 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1276 | * to userspace. |
1277 | */ | |
cdd6c482 | 1278 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1279 | { |
cdd6c482 | 1280 | u64 id = event->id; |
7f453c24 | 1281 | |
cdd6c482 IM |
1282 | if (event->parent) |
1283 | id = event->parent->id; | |
7f453c24 PZ |
1284 | |
1285 | return id; | |
1286 | } | |
1287 | ||
25346b93 | 1288 | /* |
cdd6c482 | 1289 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1290 | * |
25346b93 PM |
1291 | * This has to cope with with the fact that until it is locked, |
1292 | * the context could get moved to another task. | |
1293 | */ | |
cdd6c482 | 1294 | static struct perf_event_context * |
8dc85d54 | 1295 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1296 | { |
cdd6c482 | 1297 | struct perf_event_context *ctx; |
25346b93 | 1298 | |
9ed6060d | 1299 | retry: |
058ebd0e PZ |
1300 | /* |
1301 | * One of the few rules of preemptible RCU is that one cannot do | |
1302 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1303 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1304 | * rcu_read_unlock_special(). |
1305 | * | |
1306 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1307 | * side critical section has interrupts disabled. |
058ebd0e | 1308 | */ |
2fd59077 | 1309 | local_irq_save(*flags); |
058ebd0e | 1310 | rcu_read_lock(); |
8dc85d54 | 1311 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1312 | if (ctx) { |
1313 | /* | |
1314 | * If this context is a clone of another, it might | |
1315 | * get swapped for another underneath us by | |
cdd6c482 | 1316 | * perf_event_task_sched_out, though the |
25346b93 PM |
1317 | * rcu_read_lock() protects us from any context |
1318 | * getting freed. Lock the context and check if it | |
1319 | * got swapped before we could get the lock, and retry | |
1320 | * if so. If we locked the right context, then it | |
1321 | * can't get swapped on us any more. | |
1322 | */ | |
2fd59077 | 1323 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1324 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1325 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1326 | rcu_read_unlock(); |
2fd59077 | 1327 | local_irq_restore(*flags); |
25346b93 PM |
1328 | goto retry; |
1329 | } | |
b49a9e7e | 1330 | |
63b6da39 PZ |
1331 | if (ctx->task == TASK_TOMBSTONE || |
1332 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1333 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1334 | ctx = NULL; |
828b6f0e PZ |
1335 | } else { |
1336 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1337 | } |
25346b93 PM |
1338 | } |
1339 | rcu_read_unlock(); | |
2fd59077 PM |
1340 | if (!ctx) |
1341 | local_irq_restore(*flags); | |
25346b93 PM |
1342 | return ctx; |
1343 | } | |
1344 | ||
1345 | /* | |
1346 | * Get the context for a task and increment its pin_count so it | |
1347 | * can't get swapped to another task. This also increments its | |
1348 | * reference count so that the context can't get freed. | |
1349 | */ | |
8dc85d54 PZ |
1350 | static struct perf_event_context * |
1351 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1352 | { |
cdd6c482 | 1353 | struct perf_event_context *ctx; |
25346b93 PM |
1354 | unsigned long flags; |
1355 | ||
8dc85d54 | 1356 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1357 | if (ctx) { |
1358 | ++ctx->pin_count; | |
e625cce1 | 1359 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1360 | } |
1361 | return ctx; | |
1362 | } | |
1363 | ||
cdd6c482 | 1364 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1365 | { |
1366 | unsigned long flags; | |
1367 | ||
e625cce1 | 1368 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1369 | --ctx->pin_count; |
e625cce1 | 1370 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1371 | } |
1372 | ||
f67218c3 PZ |
1373 | /* |
1374 | * Update the record of the current time in a context. | |
1375 | */ | |
1376 | static void update_context_time(struct perf_event_context *ctx) | |
1377 | { | |
1378 | u64 now = perf_clock(); | |
1379 | ||
1380 | ctx->time += now - ctx->timestamp; | |
1381 | ctx->timestamp = now; | |
1382 | } | |
1383 | ||
4158755d SE |
1384 | static u64 perf_event_time(struct perf_event *event) |
1385 | { | |
1386 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1387 | |
1388 | if (is_cgroup_event(event)) | |
1389 | return perf_cgroup_event_time(event); | |
1390 | ||
4158755d SE |
1391 | return ctx ? ctx->time : 0; |
1392 | } | |
1393 | ||
f67218c3 PZ |
1394 | /* |
1395 | * Update the total_time_enabled and total_time_running fields for a event. | |
1396 | */ | |
1397 | static void update_event_times(struct perf_event *event) | |
1398 | { | |
1399 | struct perf_event_context *ctx = event->ctx; | |
1400 | u64 run_end; | |
1401 | ||
3cbaa590 PZ |
1402 | lockdep_assert_held(&ctx->lock); |
1403 | ||
f67218c3 PZ |
1404 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1405 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1406 | return; | |
3cbaa590 | 1407 | |
e5d1367f SE |
1408 | /* |
1409 | * in cgroup mode, time_enabled represents | |
1410 | * the time the event was enabled AND active | |
1411 | * tasks were in the monitored cgroup. This is | |
1412 | * independent of the activity of the context as | |
1413 | * there may be a mix of cgroup and non-cgroup events. | |
1414 | * | |
1415 | * That is why we treat cgroup events differently | |
1416 | * here. | |
1417 | */ | |
1418 | if (is_cgroup_event(event)) | |
46cd6a7f | 1419 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1420 | else if (ctx->is_active) |
1421 | run_end = ctx->time; | |
acd1d7c1 PZ |
1422 | else |
1423 | run_end = event->tstamp_stopped; | |
1424 | ||
1425 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1426 | |
1427 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1428 | run_end = event->tstamp_stopped; | |
1429 | else | |
4158755d | 1430 | run_end = perf_event_time(event); |
f67218c3 PZ |
1431 | |
1432 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1433 | |
f67218c3 PZ |
1434 | } |
1435 | ||
96c21a46 PZ |
1436 | /* |
1437 | * Update total_time_enabled and total_time_running for all events in a group. | |
1438 | */ | |
1439 | static void update_group_times(struct perf_event *leader) | |
1440 | { | |
1441 | struct perf_event *event; | |
1442 | ||
1443 | update_event_times(leader); | |
1444 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1445 | update_event_times(event); | |
1446 | } | |
1447 | ||
889ff015 FW |
1448 | static struct list_head * |
1449 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1450 | { | |
1451 | if (event->attr.pinned) | |
1452 | return &ctx->pinned_groups; | |
1453 | else | |
1454 | return &ctx->flexible_groups; | |
1455 | } | |
1456 | ||
fccc714b | 1457 | /* |
cdd6c482 | 1458 | * Add a event from the lists for its context. |
fccc714b PZ |
1459 | * Must be called with ctx->mutex and ctx->lock held. |
1460 | */ | |
04289bb9 | 1461 | static void |
cdd6c482 | 1462 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1463 | { |
db4a8356 | 1464 | |
c994d613 PZ |
1465 | lockdep_assert_held(&ctx->lock); |
1466 | ||
8a49542c PZ |
1467 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1468 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1469 | |
1470 | /* | |
8a49542c PZ |
1471 | * If we're a stand alone event or group leader, we go to the context |
1472 | * list, group events are kept attached to the group so that | |
1473 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1474 | */ |
8a49542c | 1475 | if (event->group_leader == event) { |
889ff015 FW |
1476 | struct list_head *list; |
1477 | ||
4ff6a8de | 1478 | event->group_caps = event->event_caps; |
d6f962b5 | 1479 | |
889ff015 FW |
1480 | list = ctx_group_list(event, ctx); |
1481 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1482 | } |
592903cd | 1483 | |
db4a8356 | 1484 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1485 | |
cdd6c482 IM |
1486 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1487 | ctx->nr_events++; | |
1488 | if (event->attr.inherit_stat) | |
bfbd3381 | 1489 | ctx->nr_stat++; |
5a3126d4 PZ |
1490 | |
1491 | ctx->generation++; | |
04289bb9 IM |
1492 | } |
1493 | ||
0231bb53 JO |
1494 | /* |
1495 | * Initialize event state based on the perf_event_attr::disabled. | |
1496 | */ | |
1497 | static inline void perf_event__state_init(struct perf_event *event) | |
1498 | { | |
1499 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1500 | PERF_EVENT_STATE_INACTIVE; | |
1501 | } | |
1502 | ||
a723968c | 1503 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1504 | { |
1505 | int entry = sizeof(u64); /* value */ | |
1506 | int size = 0; | |
1507 | int nr = 1; | |
1508 | ||
1509 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1510 | size += sizeof(u64); | |
1511 | ||
1512 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1513 | size += sizeof(u64); | |
1514 | ||
1515 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1516 | entry += sizeof(u64); | |
1517 | ||
1518 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1519 | nr += nr_siblings; |
c320c7b7 ACM |
1520 | size += sizeof(u64); |
1521 | } | |
1522 | ||
1523 | size += entry * nr; | |
1524 | event->read_size = size; | |
1525 | } | |
1526 | ||
a723968c | 1527 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1528 | { |
1529 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1530 | u16 size = 0; |
1531 | ||
c320c7b7 ACM |
1532 | if (sample_type & PERF_SAMPLE_IP) |
1533 | size += sizeof(data->ip); | |
1534 | ||
6844c09d ACM |
1535 | if (sample_type & PERF_SAMPLE_ADDR) |
1536 | size += sizeof(data->addr); | |
1537 | ||
1538 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1539 | size += sizeof(data->period); | |
1540 | ||
c3feedf2 AK |
1541 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1542 | size += sizeof(data->weight); | |
1543 | ||
6844c09d ACM |
1544 | if (sample_type & PERF_SAMPLE_READ) |
1545 | size += event->read_size; | |
1546 | ||
d6be9ad6 SE |
1547 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1548 | size += sizeof(data->data_src.val); | |
1549 | ||
fdfbbd07 AK |
1550 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1551 | size += sizeof(data->txn); | |
1552 | ||
6844c09d ACM |
1553 | event->header_size = size; |
1554 | } | |
1555 | ||
a723968c PZ |
1556 | /* |
1557 | * Called at perf_event creation and when events are attached/detached from a | |
1558 | * group. | |
1559 | */ | |
1560 | static void perf_event__header_size(struct perf_event *event) | |
1561 | { | |
1562 | __perf_event_read_size(event, | |
1563 | event->group_leader->nr_siblings); | |
1564 | __perf_event_header_size(event, event->attr.sample_type); | |
1565 | } | |
1566 | ||
6844c09d ACM |
1567 | static void perf_event__id_header_size(struct perf_event *event) |
1568 | { | |
1569 | struct perf_sample_data *data; | |
1570 | u64 sample_type = event->attr.sample_type; | |
1571 | u16 size = 0; | |
1572 | ||
c320c7b7 ACM |
1573 | if (sample_type & PERF_SAMPLE_TID) |
1574 | size += sizeof(data->tid_entry); | |
1575 | ||
1576 | if (sample_type & PERF_SAMPLE_TIME) | |
1577 | size += sizeof(data->time); | |
1578 | ||
ff3d527c AH |
1579 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1580 | size += sizeof(data->id); | |
1581 | ||
c320c7b7 ACM |
1582 | if (sample_type & PERF_SAMPLE_ID) |
1583 | size += sizeof(data->id); | |
1584 | ||
1585 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1586 | size += sizeof(data->stream_id); | |
1587 | ||
1588 | if (sample_type & PERF_SAMPLE_CPU) | |
1589 | size += sizeof(data->cpu_entry); | |
1590 | ||
6844c09d | 1591 | event->id_header_size = size; |
c320c7b7 ACM |
1592 | } |
1593 | ||
a723968c PZ |
1594 | static bool perf_event_validate_size(struct perf_event *event) |
1595 | { | |
1596 | /* | |
1597 | * The values computed here will be over-written when we actually | |
1598 | * attach the event. | |
1599 | */ | |
1600 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1601 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1602 | perf_event__id_header_size(event); | |
1603 | ||
1604 | /* | |
1605 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1606 | * Conservative limit to allow for callchains and other variable fields. | |
1607 | */ | |
1608 | if (event->read_size + event->header_size + | |
1609 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1610 | return false; | |
1611 | ||
1612 | return true; | |
1613 | } | |
1614 | ||
8a49542c PZ |
1615 | static void perf_group_attach(struct perf_event *event) |
1616 | { | |
c320c7b7 | 1617 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1618 | |
74c3337c PZ |
1619 | /* |
1620 | * We can have double attach due to group movement in perf_event_open. | |
1621 | */ | |
1622 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1623 | return; | |
1624 | ||
8a49542c PZ |
1625 | event->attach_state |= PERF_ATTACH_GROUP; |
1626 | ||
1627 | if (group_leader == event) | |
1628 | return; | |
1629 | ||
652884fe PZ |
1630 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1631 | ||
4ff6a8de | 1632 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1633 | |
1634 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1635 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1636 | |
1637 | perf_event__header_size(group_leader); | |
1638 | ||
1639 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1640 | perf_event__header_size(pos); | |
8a49542c PZ |
1641 | } |
1642 | ||
a63eaf34 | 1643 | /* |
cdd6c482 | 1644 | * Remove a event from the lists for its context. |
fccc714b | 1645 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1646 | */ |
04289bb9 | 1647 | static void |
cdd6c482 | 1648 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1649 | { |
652884fe PZ |
1650 | WARN_ON_ONCE(event->ctx != ctx); |
1651 | lockdep_assert_held(&ctx->lock); | |
1652 | ||
8a49542c PZ |
1653 | /* |
1654 | * We can have double detach due to exit/hot-unplug + close. | |
1655 | */ | |
1656 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1657 | return; |
8a49542c PZ |
1658 | |
1659 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1660 | ||
db4a8356 | 1661 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1662 | |
cdd6c482 IM |
1663 | ctx->nr_events--; |
1664 | if (event->attr.inherit_stat) | |
bfbd3381 | 1665 | ctx->nr_stat--; |
8bc20959 | 1666 | |
cdd6c482 | 1667 | list_del_rcu(&event->event_entry); |
04289bb9 | 1668 | |
8a49542c PZ |
1669 | if (event->group_leader == event) |
1670 | list_del_init(&event->group_entry); | |
5c148194 | 1671 | |
96c21a46 | 1672 | update_group_times(event); |
b2e74a26 SE |
1673 | |
1674 | /* | |
1675 | * If event was in error state, then keep it | |
1676 | * that way, otherwise bogus counts will be | |
1677 | * returned on read(). The only way to get out | |
1678 | * of error state is by explicit re-enabling | |
1679 | * of the event | |
1680 | */ | |
1681 | if (event->state > PERF_EVENT_STATE_OFF) | |
1682 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1683 | |
1684 | ctx->generation++; | |
050735b0 PZ |
1685 | } |
1686 | ||
8a49542c | 1687 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1688 | { |
1689 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1690 | struct list_head *list = NULL; |
1691 | ||
1692 | /* | |
1693 | * We can have double detach due to exit/hot-unplug + close. | |
1694 | */ | |
1695 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1696 | return; | |
1697 | ||
1698 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1699 | ||
1700 | /* | |
1701 | * If this is a sibling, remove it from its group. | |
1702 | */ | |
1703 | if (event->group_leader != event) { | |
1704 | list_del_init(&event->group_entry); | |
1705 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1706 | goto out; |
8a49542c PZ |
1707 | } |
1708 | ||
1709 | if (!list_empty(&event->group_entry)) | |
1710 | list = &event->group_entry; | |
2e2af50b | 1711 | |
04289bb9 | 1712 | /* |
cdd6c482 IM |
1713 | * If this was a group event with sibling events then |
1714 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1715 | * to whatever list we are on. |
04289bb9 | 1716 | */ |
cdd6c482 | 1717 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1718 | if (list) |
1719 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1720 | sibling->group_leader = sibling; |
d6f962b5 FW |
1721 | |
1722 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1723 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1724 | |
1725 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1726 | } |
c320c7b7 ACM |
1727 | |
1728 | out: | |
1729 | perf_event__header_size(event->group_leader); | |
1730 | ||
1731 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1732 | perf_event__header_size(tmp); | |
04289bb9 IM |
1733 | } |
1734 | ||
fadfe7be JO |
1735 | static bool is_orphaned_event(struct perf_event *event) |
1736 | { | |
a69b0ca4 | 1737 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1738 | } |
1739 | ||
2c81a647 | 1740 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1741 | { |
1742 | struct pmu *pmu = event->pmu; | |
1743 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1744 | } | |
1745 | ||
2c81a647 MR |
1746 | /* |
1747 | * Check whether we should attempt to schedule an event group based on | |
1748 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1749 | * potentially with a SW leader, so we must check all the filters, to | |
1750 | * determine whether a group is schedulable: | |
1751 | */ | |
1752 | static inline int pmu_filter_match(struct perf_event *event) | |
1753 | { | |
1754 | struct perf_event *child; | |
1755 | ||
1756 | if (!__pmu_filter_match(event)) | |
1757 | return 0; | |
1758 | ||
1759 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1760 | if (!__pmu_filter_match(child)) | |
1761 | return 0; | |
1762 | } | |
1763 | ||
1764 | return 1; | |
1765 | } | |
1766 | ||
fa66f07a SE |
1767 | static inline int |
1768 | event_filter_match(struct perf_event *event) | |
1769 | { | |
0b8f1e2e PZ |
1770 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1771 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1772 | } |
1773 | ||
9ffcfa6f SE |
1774 | static void |
1775 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1776 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1777 | struct perf_event_context *ctx) |
3b6f9e5c | 1778 | { |
4158755d | 1779 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1780 | u64 delta; |
652884fe PZ |
1781 | |
1782 | WARN_ON_ONCE(event->ctx != ctx); | |
1783 | lockdep_assert_held(&ctx->lock); | |
1784 | ||
fa66f07a SE |
1785 | /* |
1786 | * An event which could not be activated because of | |
1787 | * filter mismatch still needs to have its timings | |
1788 | * maintained, otherwise bogus information is return | |
1789 | * via read() for time_enabled, time_running: | |
1790 | */ | |
0b8f1e2e PZ |
1791 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1792 | !event_filter_match(event)) { | |
e5d1367f | 1793 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1794 | event->tstamp_running += delta; |
4158755d | 1795 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1796 | } |
1797 | ||
cdd6c482 | 1798 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1799 | return; |
3b6f9e5c | 1800 | |
44377277 AS |
1801 | perf_pmu_disable(event->pmu); |
1802 | ||
28a967c3 PZ |
1803 | event->tstamp_stopped = tstamp; |
1804 | event->pmu->del(event, 0); | |
1805 | event->oncpu = -1; | |
cdd6c482 IM |
1806 | event->state = PERF_EVENT_STATE_INACTIVE; |
1807 | if (event->pending_disable) { | |
1808 | event->pending_disable = 0; | |
1809 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1810 | } |
3b6f9e5c | 1811 | |
cdd6c482 | 1812 | if (!is_software_event(event)) |
3b6f9e5c | 1813 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1814 | if (!--ctx->nr_active) |
1815 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1816 | if (event->attr.freq && event->attr.sample_freq) |
1817 | ctx->nr_freq--; | |
cdd6c482 | 1818 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1819 | cpuctx->exclusive = 0; |
44377277 AS |
1820 | |
1821 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1822 | } |
1823 | ||
d859e29f | 1824 | static void |
cdd6c482 | 1825 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1826 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1827 | struct perf_event_context *ctx) |
d859e29f | 1828 | { |
cdd6c482 | 1829 | struct perf_event *event; |
fa66f07a | 1830 | int state = group_event->state; |
d859e29f | 1831 | |
3f005e7d MR |
1832 | perf_pmu_disable(ctx->pmu); |
1833 | ||
cdd6c482 | 1834 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1835 | |
1836 | /* | |
1837 | * Schedule out siblings (if any): | |
1838 | */ | |
cdd6c482 IM |
1839 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1840 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1841 | |
3f005e7d MR |
1842 | perf_pmu_enable(ctx->pmu); |
1843 | ||
fa66f07a | 1844 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1845 | cpuctx->exclusive = 0; |
1846 | } | |
1847 | ||
45a0e07a | 1848 | #define DETACH_GROUP 0x01UL |
0017960f | 1849 | |
0793a61d | 1850 | /* |
cdd6c482 | 1851 | * Cross CPU call to remove a performance event |
0793a61d | 1852 | * |
cdd6c482 | 1853 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1854 | * remove it from the context list. |
1855 | */ | |
fae3fde6 PZ |
1856 | static void |
1857 | __perf_remove_from_context(struct perf_event *event, | |
1858 | struct perf_cpu_context *cpuctx, | |
1859 | struct perf_event_context *ctx, | |
1860 | void *info) | |
0793a61d | 1861 | { |
45a0e07a | 1862 | unsigned long flags = (unsigned long)info; |
0793a61d | 1863 | |
cdd6c482 | 1864 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1865 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1866 | perf_group_detach(event); |
cdd6c482 | 1867 | list_del_event(event, ctx); |
39a43640 PZ |
1868 | |
1869 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1870 | ctx->is_active = 0; |
39a43640 PZ |
1871 | if (ctx->task) { |
1872 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1873 | cpuctx->task_ctx = NULL; | |
1874 | } | |
64ce3126 | 1875 | } |
0793a61d TG |
1876 | } |
1877 | ||
0793a61d | 1878 | /* |
cdd6c482 | 1879 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1880 | * |
cdd6c482 IM |
1881 | * If event->ctx is a cloned context, callers must make sure that |
1882 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1883 | * remains valid. This is OK when called from perf_release since |
1884 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1885 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1886 | * context has been detached from its task. |
0793a61d | 1887 | */ |
45a0e07a | 1888 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1889 | { |
fae3fde6 | 1890 | lockdep_assert_held(&event->ctx->mutex); |
0793a61d | 1891 | |
45a0e07a | 1892 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
0793a61d TG |
1893 | } |
1894 | ||
d859e29f | 1895 | /* |
cdd6c482 | 1896 | * Cross CPU call to disable a performance event |
d859e29f | 1897 | */ |
fae3fde6 PZ |
1898 | static void __perf_event_disable(struct perf_event *event, |
1899 | struct perf_cpu_context *cpuctx, | |
1900 | struct perf_event_context *ctx, | |
1901 | void *info) | |
7b648018 | 1902 | { |
fae3fde6 PZ |
1903 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1904 | return; | |
7b648018 | 1905 | |
fae3fde6 PZ |
1906 | update_context_time(ctx); |
1907 | update_cgrp_time_from_event(event); | |
1908 | update_group_times(event); | |
1909 | if (event == event->group_leader) | |
1910 | group_sched_out(event, cpuctx, ctx); | |
1911 | else | |
1912 | event_sched_out(event, cpuctx, ctx); | |
1913 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1914 | } |
1915 | ||
d859e29f | 1916 | /* |
cdd6c482 | 1917 | * Disable a event. |
c93f7669 | 1918 | * |
cdd6c482 IM |
1919 | * If event->ctx is a cloned context, callers must make sure that |
1920 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1921 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1922 | * perf_event_for_each_child or perf_event_for_each because they |
1923 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1924 | * goes to exit will block in perf_event_exit_event(). |
1925 | * | |
cdd6c482 | 1926 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1927 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1928 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1929 | */ |
f63a8daa | 1930 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1931 | { |
cdd6c482 | 1932 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1933 | |
e625cce1 | 1934 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1935 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1936 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1937 | return; |
53cfbf59 | 1938 | } |
e625cce1 | 1939 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1940 | |
fae3fde6 PZ |
1941 | event_function_call(event, __perf_event_disable, NULL); |
1942 | } | |
1943 | ||
1944 | void perf_event_disable_local(struct perf_event *event) | |
1945 | { | |
1946 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1947 | } |
f63a8daa PZ |
1948 | |
1949 | /* | |
1950 | * Strictly speaking kernel users cannot create groups and therefore this | |
1951 | * interface does not need the perf_event_ctx_lock() magic. | |
1952 | */ | |
1953 | void perf_event_disable(struct perf_event *event) | |
1954 | { | |
1955 | struct perf_event_context *ctx; | |
1956 | ||
1957 | ctx = perf_event_ctx_lock(event); | |
1958 | _perf_event_disable(event); | |
1959 | perf_event_ctx_unlock(event, ctx); | |
1960 | } | |
dcfce4a0 | 1961 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1962 | |
e5d1367f SE |
1963 | static void perf_set_shadow_time(struct perf_event *event, |
1964 | struct perf_event_context *ctx, | |
1965 | u64 tstamp) | |
1966 | { | |
1967 | /* | |
1968 | * use the correct time source for the time snapshot | |
1969 | * | |
1970 | * We could get by without this by leveraging the | |
1971 | * fact that to get to this function, the caller | |
1972 | * has most likely already called update_context_time() | |
1973 | * and update_cgrp_time_xx() and thus both timestamp | |
1974 | * are identical (or very close). Given that tstamp is, | |
1975 | * already adjusted for cgroup, we could say that: | |
1976 | * tstamp - ctx->timestamp | |
1977 | * is equivalent to | |
1978 | * tstamp - cgrp->timestamp. | |
1979 | * | |
1980 | * Then, in perf_output_read(), the calculation would | |
1981 | * work with no changes because: | |
1982 | * - event is guaranteed scheduled in | |
1983 | * - no scheduled out in between | |
1984 | * - thus the timestamp would be the same | |
1985 | * | |
1986 | * But this is a bit hairy. | |
1987 | * | |
1988 | * So instead, we have an explicit cgroup call to remain | |
1989 | * within the time time source all along. We believe it | |
1990 | * is cleaner and simpler to understand. | |
1991 | */ | |
1992 | if (is_cgroup_event(event)) | |
1993 | perf_cgroup_set_shadow_time(event, tstamp); | |
1994 | else | |
1995 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1996 | } | |
1997 | ||
4fe757dd PZ |
1998 | #define MAX_INTERRUPTS (~0ULL) |
1999 | ||
2000 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2001 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2002 | |
235c7fc7 | 2003 | static int |
9ffcfa6f | 2004 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2005 | struct perf_cpu_context *cpuctx, |
6e37738a | 2006 | struct perf_event_context *ctx) |
235c7fc7 | 2007 | { |
4158755d | 2008 | u64 tstamp = perf_event_time(event); |
44377277 | 2009 | int ret = 0; |
4158755d | 2010 | |
63342411 PZ |
2011 | lockdep_assert_held(&ctx->lock); |
2012 | ||
cdd6c482 | 2013 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2014 | return 0; |
2015 | ||
95ff4ca2 AS |
2016 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2017 | /* | |
2018 | * Order event::oncpu write to happen before the ACTIVE state | |
2019 | * is visible. | |
2020 | */ | |
2021 | smp_wmb(); | |
2022 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
2023 | |
2024 | /* | |
2025 | * Unthrottle events, since we scheduled we might have missed several | |
2026 | * ticks already, also for a heavily scheduling task there is little | |
2027 | * guarantee it'll get a tick in a timely manner. | |
2028 | */ | |
2029 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2030 | perf_log_throttle(event, 1); | |
2031 | event->hw.interrupts = 0; | |
2032 | } | |
2033 | ||
235c7fc7 IM |
2034 | /* |
2035 | * The new state must be visible before we turn it on in the hardware: | |
2036 | */ | |
2037 | smp_wmb(); | |
2038 | ||
44377277 AS |
2039 | perf_pmu_disable(event->pmu); |
2040 | ||
72f669c0 SL |
2041 | perf_set_shadow_time(event, ctx, tstamp); |
2042 | ||
ec0d7729 AS |
2043 | perf_log_itrace_start(event); |
2044 | ||
a4eaf7f1 | 2045 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
2046 | event->state = PERF_EVENT_STATE_INACTIVE; |
2047 | event->oncpu = -1; | |
44377277 AS |
2048 | ret = -EAGAIN; |
2049 | goto out; | |
235c7fc7 IM |
2050 | } |
2051 | ||
00a2916f PZ |
2052 | event->tstamp_running += tstamp - event->tstamp_stopped; |
2053 | ||
cdd6c482 | 2054 | if (!is_software_event(event)) |
3b6f9e5c | 2055 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2056 | if (!ctx->nr_active++) |
2057 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2058 | if (event->attr.freq && event->attr.sample_freq) |
2059 | ctx->nr_freq++; | |
235c7fc7 | 2060 | |
cdd6c482 | 2061 | if (event->attr.exclusive) |
3b6f9e5c PM |
2062 | cpuctx->exclusive = 1; |
2063 | ||
44377277 AS |
2064 | out: |
2065 | perf_pmu_enable(event->pmu); | |
2066 | ||
2067 | return ret; | |
235c7fc7 IM |
2068 | } |
2069 | ||
6751b71e | 2070 | static int |
cdd6c482 | 2071 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2072 | struct perf_cpu_context *cpuctx, |
6e37738a | 2073 | struct perf_event_context *ctx) |
6751b71e | 2074 | { |
6bde9b6c | 2075 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2076 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2077 | u64 now = ctx->time; |
2078 | bool simulate = false; | |
6751b71e | 2079 | |
cdd6c482 | 2080 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2081 | return 0; |
2082 | ||
fbbe0701 | 2083 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2084 | |
9ffcfa6f | 2085 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2086 | pmu->cancel_txn(pmu); |
272325c4 | 2087 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2088 | return -EAGAIN; |
90151c35 | 2089 | } |
6751b71e PM |
2090 | |
2091 | /* | |
2092 | * Schedule in siblings as one group (if any): | |
2093 | */ | |
cdd6c482 | 2094 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2095 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2096 | partial_group = event; |
6751b71e PM |
2097 | goto group_error; |
2098 | } | |
2099 | } | |
2100 | ||
9ffcfa6f | 2101 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2102 | return 0; |
9ffcfa6f | 2103 | |
6751b71e PM |
2104 | group_error: |
2105 | /* | |
2106 | * Groups can be scheduled in as one unit only, so undo any | |
2107 | * partial group before returning: | |
d7842da4 SE |
2108 | * The events up to the failed event are scheduled out normally, |
2109 | * tstamp_stopped will be updated. | |
2110 | * | |
2111 | * The failed events and the remaining siblings need to have | |
2112 | * their timings updated as if they had gone thru event_sched_in() | |
2113 | * and event_sched_out(). This is required to get consistent timings | |
2114 | * across the group. This also takes care of the case where the group | |
2115 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2116 | * the time the event was actually stopped, such that time delta | |
2117 | * calculation in update_event_times() is correct. | |
6751b71e | 2118 | */ |
cdd6c482 IM |
2119 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2120 | if (event == partial_group) | |
d7842da4 SE |
2121 | simulate = true; |
2122 | ||
2123 | if (simulate) { | |
2124 | event->tstamp_running += now - event->tstamp_stopped; | |
2125 | event->tstamp_stopped = now; | |
2126 | } else { | |
2127 | event_sched_out(event, cpuctx, ctx); | |
2128 | } | |
6751b71e | 2129 | } |
9ffcfa6f | 2130 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2131 | |
ad5133b7 | 2132 | pmu->cancel_txn(pmu); |
90151c35 | 2133 | |
272325c4 | 2134 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2135 | |
6751b71e PM |
2136 | return -EAGAIN; |
2137 | } | |
2138 | ||
3b6f9e5c | 2139 | /* |
cdd6c482 | 2140 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2141 | */ |
cdd6c482 | 2142 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2143 | struct perf_cpu_context *cpuctx, |
2144 | int can_add_hw) | |
2145 | { | |
2146 | /* | |
cdd6c482 | 2147 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2148 | */ |
4ff6a8de | 2149 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2150 | return 1; |
2151 | /* | |
2152 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2153 | * events can go on. |
3b6f9e5c PM |
2154 | */ |
2155 | if (cpuctx->exclusive) | |
2156 | return 0; | |
2157 | /* | |
2158 | * If this group is exclusive and there are already | |
cdd6c482 | 2159 | * events on the CPU, it can't go on. |
3b6f9e5c | 2160 | */ |
cdd6c482 | 2161 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2162 | return 0; |
2163 | /* | |
2164 | * Otherwise, try to add it if all previous groups were able | |
2165 | * to go on. | |
2166 | */ | |
2167 | return can_add_hw; | |
2168 | } | |
2169 | ||
cdd6c482 IM |
2170 | static void add_event_to_ctx(struct perf_event *event, |
2171 | struct perf_event_context *ctx) | |
53cfbf59 | 2172 | { |
4158755d SE |
2173 | u64 tstamp = perf_event_time(event); |
2174 | ||
cdd6c482 | 2175 | list_add_event(event, ctx); |
8a49542c | 2176 | perf_group_attach(event); |
4158755d SE |
2177 | event->tstamp_enabled = tstamp; |
2178 | event->tstamp_running = tstamp; | |
2179 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2180 | } |
2181 | ||
bd2afa49 PZ |
2182 | static void ctx_sched_out(struct perf_event_context *ctx, |
2183 | struct perf_cpu_context *cpuctx, | |
2184 | enum event_type_t event_type); | |
2c29ef0f PZ |
2185 | static void |
2186 | ctx_sched_in(struct perf_event_context *ctx, | |
2187 | struct perf_cpu_context *cpuctx, | |
2188 | enum event_type_t event_type, | |
2189 | struct task_struct *task); | |
fe4b04fa | 2190 | |
bd2afa49 PZ |
2191 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
2192 | struct perf_event_context *ctx) | |
2193 | { | |
2194 | if (!cpuctx->task_ctx) | |
2195 | return; | |
2196 | ||
2197 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2198 | return; | |
2199 | ||
2200 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); | |
2201 | } | |
2202 | ||
dce5855b PZ |
2203 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2204 | struct perf_event_context *ctx, | |
2205 | struct task_struct *task) | |
2206 | { | |
2207 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2208 | if (ctx) | |
2209 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2210 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2211 | if (ctx) | |
2212 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2213 | } | |
2214 | ||
3e349507 PZ |
2215 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
2216 | struct perf_event_context *task_ctx) | |
0017960f | 2217 | { |
3e349507 PZ |
2218 | perf_pmu_disable(cpuctx->ctx.pmu); |
2219 | if (task_ctx) | |
2220 | task_ctx_sched_out(cpuctx, task_ctx); | |
2221 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
2222 | perf_event_sched_in(cpuctx, task_ctx, current); | |
2223 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2224 | } |
2225 | ||
0793a61d | 2226 | /* |
cdd6c482 | 2227 | * Cross CPU call to install and enable a performance event |
682076ae | 2228 | * |
a096309b PZ |
2229 | * Very similar to remote_function() + event_function() but cannot assume that |
2230 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2231 | */ |
fe4b04fa | 2232 | static int __perf_install_in_context(void *info) |
0793a61d | 2233 | { |
a096309b PZ |
2234 | struct perf_event *event = info; |
2235 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2236 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2237 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
a096309b PZ |
2238 | bool activate = true; |
2239 | int ret = 0; | |
0793a61d | 2240 | |
63b6da39 | 2241 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2242 | if (ctx->task) { |
b58f6b0d PZ |
2243 | raw_spin_lock(&ctx->lock); |
2244 | task_ctx = ctx; | |
a096309b PZ |
2245 | |
2246 | /* If we're on the wrong CPU, try again */ | |
2247 | if (task_cpu(ctx->task) != smp_processor_id()) { | |
2248 | ret = -ESRCH; | |
63b6da39 | 2249 | goto unlock; |
a096309b | 2250 | } |
b58f6b0d | 2251 | |
39a43640 | 2252 | /* |
a096309b PZ |
2253 | * If we're on the right CPU, see if the task we target is |
2254 | * current, if not we don't have to activate the ctx, a future | |
2255 | * context switch will do that for us. | |
39a43640 | 2256 | */ |
a096309b PZ |
2257 | if (ctx->task != current) |
2258 | activate = false; | |
2259 | else | |
2260 | WARN_ON_ONCE(cpuctx->task_ctx && cpuctx->task_ctx != ctx); | |
2261 | ||
63b6da39 PZ |
2262 | } else if (task_ctx) { |
2263 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2264 | } |
b58f6b0d | 2265 | |
a096309b PZ |
2266 | if (activate) { |
2267 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2268 | add_event_to_ctx(event, ctx); | |
2269 | ctx_resched(cpuctx, task_ctx); | |
2270 | } else { | |
2271 | add_event_to_ctx(event, ctx); | |
2272 | } | |
2273 | ||
63b6da39 | 2274 | unlock: |
2c29ef0f | 2275 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2276 | |
a096309b | 2277 | return ret; |
0793a61d TG |
2278 | } |
2279 | ||
2280 | /* | |
a096309b PZ |
2281 | * Attach a performance event to a context. |
2282 | * | |
2283 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2284 | */ |
2285 | static void | |
cdd6c482 IM |
2286 | perf_install_in_context(struct perf_event_context *ctx, |
2287 | struct perf_event *event, | |
0793a61d TG |
2288 | int cpu) |
2289 | { | |
a096309b | 2290 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2291 | |
fe4b04fa PZ |
2292 | lockdep_assert_held(&ctx->mutex); |
2293 | ||
0cda4c02 YZ |
2294 | if (event->cpu != -1) |
2295 | event->cpu = cpu; | |
c3f00c70 | 2296 | |
0b8f1e2e PZ |
2297 | /* |
2298 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2299 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2300 | */ | |
2301 | smp_store_release(&event->ctx, ctx); | |
2302 | ||
a096309b PZ |
2303 | if (!task) { |
2304 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2305 | return; | |
2306 | } | |
2307 | ||
2308 | /* | |
2309 | * Should not happen, we validate the ctx is still alive before calling. | |
2310 | */ | |
2311 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2312 | return; | |
2313 | ||
39a43640 PZ |
2314 | /* |
2315 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2316 | * to be set in case this is the nr_events 0 -> 1 transition. | |
39a43640 | 2317 | */ |
a096309b | 2318 | again: |
63b6da39 | 2319 | /* |
a096309b PZ |
2320 | * Cannot use task_function_call() because we need to run on the task's |
2321 | * CPU regardless of whether its current or not. | |
63b6da39 | 2322 | */ |
a096309b PZ |
2323 | if (!cpu_function_call(task_cpu(task), __perf_install_in_context, event)) |
2324 | return; | |
2325 | ||
2326 | raw_spin_lock_irq(&ctx->lock); | |
2327 | task = ctx->task; | |
84c4e620 | 2328 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2329 | /* |
2330 | * Cannot happen because we already checked above (which also | |
2331 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2332 | * against perf_event_exit_task_context(). | |
2333 | */ | |
63b6da39 PZ |
2334 | raw_spin_unlock_irq(&ctx->lock); |
2335 | return; | |
2336 | } | |
39a43640 | 2337 | raw_spin_unlock_irq(&ctx->lock); |
39a43640 | 2338 | /* |
a096309b PZ |
2339 | * Since !ctx->is_active doesn't mean anything, we must IPI |
2340 | * unconditionally. | |
39a43640 | 2341 | */ |
a096309b | 2342 | goto again; |
0793a61d TG |
2343 | } |
2344 | ||
fa289bec | 2345 | /* |
cdd6c482 | 2346 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2347 | * Enabling the leader of a group effectively enables all |
2348 | * the group members that aren't explicitly disabled, so we | |
2349 | * have to update their ->tstamp_enabled also. | |
2350 | * Note: this works for group members as well as group leaders | |
2351 | * since the non-leader members' sibling_lists will be empty. | |
2352 | */ | |
1d9b482e | 2353 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2354 | { |
cdd6c482 | 2355 | struct perf_event *sub; |
4158755d | 2356 | u64 tstamp = perf_event_time(event); |
fa289bec | 2357 | |
cdd6c482 | 2358 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2359 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2360 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2361 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2362 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2363 | } |
fa289bec PM |
2364 | } |
2365 | ||
d859e29f | 2366 | /* |
cdd6c482 | 2367 | * Cross CPU call to enable a performance event |
d859e29f | 2368 | */ |
fae3fde6 PZ |
2369 | static void __perf_event_enable(struct perf_event *event, |
2370 | struct perf_cpu_context *cpuctx, | |
2371 | struct perf_event_context *ctx, | |
2372 | void *info) | |
04289bb9 | 2373 | { |
cdd6c482 | 2374 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2375 | struct perf_event_context *task_ctx; |
04289bb9 | 2376 | |
6e801e01 PZ |
2377 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2378 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2379 | return; |
3cbed429 | 2380 | |
bd2afa49 PZ |
2381 | if (ctx->is_active) |
2382 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2383 | ||
1d9b482e | 2384 | __perf_event_mark_enabled(event); |
04289bb9 | 2385 | |
fae3fde6 PZ |
2386 | if (!ctx->is_active) |
2387 | return; | |
2388 | ||
e5d1367f | 2389 | if (!event_filter_match(event)) { |
bd2afa49 | 2390 | if (is_cgroup_event(event)) |
e5d1367f | 2391 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2392 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2393 | return; |
e5d1367f | 2394 | } |
f4c4176f | 2395 | |
04289bb9 | 2396 | /* |
cdd6c482 | 2397 | * If the event is in a group and isn't the group leader, |
d859e29f | 2398 | * then don't put it on unless the group is on. |
04289bb9 | 2399 | */ |
bd2afa49 PZ |
2400 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2401 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2402 | return; |
bd2afa49 | 2403 | } |
fe4b04fa | 2404 | |
fae3fde6 PZ |
2405 | task_ctx = cpuctx->task_ctx; |
2406 | if (ctx->task) | |
2407 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2408 | |
fae3fde6 | 2409 | ctx_resched(cpuctx, task_ctx); |
7b648018 PZ |
2410 | } |
2411 | ||
d859e29f | 2412 | /* |
cdd6c482 | 2413 | * Enable a event. |
c93f7669 | 2414 | * |
cdd6c482 IM |
2415 | * If event->ctx is a cloned context, callers must make sure that |
2416 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2417 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2418 | * perf_event_for_each_child or perf_event_for_each as described |
2419 | * for perf_event_disable. | |
d859e29f | 2420 | */ |
f63a8daa | 2421 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2422 | { |
cdd6c482 | 2423 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2424 | |
7b648018 | 2425 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2426 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2427 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2428 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2429 | return; |
2430 | } | |
2431 | ||
d859e29f | 2432 | /* |
cdd6c482 | 2433 | * If the event is in error state, clear that first. |
7b648018 PZ |
2434 | * |
2435 | * That way, if we see the event in error state below, we know that it | |
2436 | * has gone back into error state, as distinct from the task having | |
2437 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2438 | */ |
cdd6c482 IM |
2439 | if (event->state == PERF_EVENT_STATE_ERROR) |
2440 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2441 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2442 | |
fae3fde6 | 2443 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2444 | } |
f63a8daa PZ |
2445 | |
2446 | /* | |
2447 | * See perf_event_disable(); | |
2448 | */ | |
2449 | void perf_event_enable(struct perf_event *event) | |
2450 | { | |
2451 | struct perf_event_context *ctx; | |
2452 | ||
2453 | ctx = perf_event_ctx_lock(event); | |
2454 | _perf_event_enable(event); | |
2455 | perf_event_ctx_unlock(event, ctx); | |
2456 | } | |
dcfce4a0 | 2457 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2458 | |
375637bc AS |
2459 | struct stop_event_data { |
2460 | struct perf_event *event; | |
2461 | unsigned int restart; | |
2462 | }; | |
2463 | ||
95ff4ca2 AS |
2464 | static int __perf_event_stop(void *info) |
2465 | { | |
375637bc AS |
2466 | struct stop_event_data *sd = info; |
2467 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2468 | |
375637bc | 2469 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2470 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2471 | return 0; | |
2472 | ||
2473 | /* matches smp_wmb() in event_sched_in() */ | |
2474 | smp_rmb(); | |
2475 | ||
2476 | /* | |
2477 | * There is a window with interrupts enabled before we get here, | |
2478 | * so we need to check again lest we try to stop another CPU's event. | |
2479 | */ | |
2480 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2481 | return -EAGAIN; | |
2482 | ||
2483 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2484 | ||
375637bc AS |
2485 | /* |
2486 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2487 | * but it is only used for events with AUX ring buffer, and such | |
2488 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2489 | * see comments in perf_aux_output_begin(). | |
2490 | * | |
2491 | * Since this is happening on a event-local CPU, no trace is lost | |
2492 | * while restarting. | |
2493 | */ | |
2494 | if (sd->restart) | |
2495 | event->pmu->start(event, PERF_EF_START); | |
2496 | ||
95ff4ca2 AS |
2497 | return 0; |
2498 | } | |
2499 | ||
375637bc AS |
2500 | static int perf_event_restart(struct perf_event *event) |
2501 | { | |
2502 | struct stop_event_data sd = { | |
2503 | .event = event, | |
2504 | .restart = 1, | |
2505 | }; | |
2506 | int ret = 0; | |
2507 | ||
2508 | do { | |
2509 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2510 | return 0; | |
2511 | ||
2512 | /* matches smp_wmb() in event_sched_in() */ | |
2513 | smp_rmb(); | |
2514 | ||
2515 | /* | |
2516 | * We only want to restart ACTIVE events, so if the event goes | |
2517 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2518 | * fall through with ret==-ENXIO. | |
2519 | */ | |
2520 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2521 | __perf_event_stop, &sd); | |
2522 | } while (ret == -EAGAIN); | |
2523 | ||
2524 | return ret; | |
2525 | } | |
2526 | ||
2527 | /* | |
2528 | * In order to contain the amount of racy and tricky in the address filter | |
2529 | * configuration management, it is a two part process: | |
2530 | * | |
2531 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2532 | * we update the addresses of corresponding vmas in | |
2533 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2534 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2535 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2536 | * if the generation has changed since the previous call. | |
2537 | * | |
2538 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2539 | * | |
2540 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2541 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2542 | * ioctl; | |
2543 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2544 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2545 | * for reading; | |
2546 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2547 | * of exec. | |
2548 | */ | |
2549 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2550 | { | |
2551 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2552 | ||
2553 | if (!has_addr_filter(event)) | |
2554 | return; | |
2555 | ||
2556 | raw_spin_lock(&ifh->lock); | |
2557 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2558 | event->pmu->addr_filters_sync(event); | |
2559 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2560 | } | |
2561 | raw_spin_unlock(&ifh->lock); | |
2562 | } | |
2563 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2564 | ||
f63a8daa | 2565 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2566 | { |
2023b359 | 2567 | /* |
cdd6c482 | 2568 | * not supported on inherited events |
2023b359 | 2569 | */ |
2e939d1d | 2570 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2571 | return -EINVAL; |
2572 | ||
cdd6c482 | 2573 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2574 | _perf_event_enable(event); |
2023b359 PZ |
2575 | |
2576 | return 0; | |
79f14641 | 2577 | } |
f63a8daa PZ |
2578 | |
2579 | /* | |
2580 | * See perf_event_disable() | |
2581 | */ | |
2582 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2583 | { | |
2584 | struct perf_event_context *ctx; | |
2585 | int ret; | |
2586 | ||
2587 | ctx = perf_event_ctx_lock(event); | |
2588 | ret = _perf_event_refresh(event, refresh); | |
2589 | perf_event_ctx_unlock(event, ctx); | |
2590 | ||
2591 | return ret; | |
2592 | } | |
26ca5c11 | 2593 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2594 | |
5b0311e1 FW |
2595 | static void ctx_sched_out(struct perf_event_context *ctx, |
2596 | struct perf_cpu_context *cpuctx, | |
2597 | enum event_type_t event_type) | |
235c7fc7 | 2598 | { |
db24d33e | 2599 | int is_active = ctx->is_active; |
c994d613 | 2600 | struct perf_event *event; |
235c7fc7 | 2601 | |
c994d613 | 2602 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2603 | |
39a43640 PZ |
2604 | if (likely(!ctx->nr_events)) { |
2605 | /* | |
2606 | * See __perf_remove_from_context(). | |
2607 | */ | |
2608 | WARN_ON_ONCE(ctx->is_active); | |
2609 | if (ctx->task) | |
2610 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2611 | return; |
39a43640 PZ |
2612 | } |
2613 | ||
db24d33e | 2614 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2615 | if (!(ctx->is_active & EVENT_ALL)) |
2616 | ctx->is_active = 0; | |
2617 | ||
63e30d3e PZ |
2618 | if (ctx->task) { |
2619 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2620 | if (!ctx->is_active) | |
2621 | cpuctx->task_ctx = NULL; | |
2622 | } | |
facc4307 | 2623 | |
8fdc6539 PZ |
2624 | /* |
2625 | * Always update time if it was set; not only when it changes. | |
2626 | * Otherwise we can 'forget' to update time for any but the last | |
2627 | * context we sched out. For example: | |
2628 | * | |
2629 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2630 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2631 | * | |
2632 | * would only update time for the pinned events. | |
2633 | */ | |
3cbaa590 PZ |
2634 | if (is_active & EVENT_TIME) { |
2635 | /* update (and stop) ctx time */ | |
2636 | update_context_time(ctx); | |
2637 | update_cgrp_time_from_cpuctx(cpuctx); | |
2638 | } | |
2639 | ||
8fdc6539 PZ |
2640 | is_active ^= ctx->is_active; /* changed bits */ |
2641 | ||
3cbaa590 | 2642 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2643 | return; |
5b0311e1 | 2644 | |
075e0b00 | 2645 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2646 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2647 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2648 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2649 | } |
889ff015 | 2650 | |
3cbaa590 | 2651 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2652 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2653 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2654 | } |
1b9a644f | 2655 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2656 | } |
2657 | ||
564c2b21 | 2658 | /* |
5a3126d4 PZ |
2659 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2660 | * cloned from the same version of the same context. | |
2661 | * | |
2662 | * Equivalence is measured using a generation number in the context that is | |
2663 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2664 | * and list_del_event(). | |
564c2b21 | 2665 | */ |
cdd6c482 IM |
2666 | static int context_equiv(struct perf_event_context *ctx1, |
2667 | struct perf_event_context *ctx2) | |
564c2b21 | 2668 | { |
211de6eb PZ |
2669 | lockdep_assert_held(&ctx1->lock); |
2670 | lockdep_assert_held(&ctx2->lock); | |
2671 | ||
5a3126d4 PZ |
2672 | /* Pinning disables the swap optimization */ |
2673 | if (ctx1->pin_count || ctx2->pin_count) | |
2674 | return 0; | |
2675 | ||
2676 | /* If ctx1 is the parent of ctx2 */ | |
2677 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2678 | return 1; | |
2679 | ||
2680 | /* If ctx2 is the parent of ctx1 */ | |
2681 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2682 | return 1; | |
2683 | ||
2684 | /* | |
2685 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2686 | * hierarchy, see perf_event_init_context(). | |
2687 | */ | |
2688 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2689 | ctx1->parent_gen == ctx2->parent_gen) | |
2690 | return 1; | |
2691 | ||
2692 | /* Unmatched */ | |
2693 | return 0; | |
564c2b21 PM |
2694 | } |
2695 | ||
cdd6c482 IM |
2696 | static void __perf_event_sync_stat(struct perf_event *event, |
2697 | struct perf_event *next_event) | |
bfbd3381 PZ |
2698 | { |
2699 | u64 value; | |
2700 | ||
cdd6c482 | 2701 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2702 | return; |
2703 | ||
2704 | /* | |
cdd6c482 | 2705 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2706 | * because we're in the middle of a context switch and have IRQs |
2707 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2708 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2709 | * don't need to use it. |
2710 | */ | |
cdd6c482 IM |
2711 | switch (event->state) { |
2712 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2713 | event->pmu->read(event); |
2714 | /* fall-through */ | |
bfbd3381 | 2715 | |
cdd6c482 IM |
2716 | case PERF_EVENT_STATE_INACTIVE: |
2717 | update_event_times(event); | |
bfbd3381 PZ |
2718 | break; |
2719 | ||
2720 | default: | |
2721 | break; | |
2722 | } | |
2723 | ||
2724 | /* | |
cdd6c482 | 2725 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2726 | * values when we flip the contexts. |
2727 | */ | |
e7850595 PZ |
2728 | value = local64_read(&next_event->count); |
2729 | value = local64_xchg(&event->count, value); | |
2730 | local64_set(&next_event->count, value); | |
bfbd3381 | 2731 | |
cdd6c482 IM |
2732 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2733 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2734 | |
bfbd3381 | 2735 | /* |
19d2e755 | 2736 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2737 | */ |
cdd6c482 IM |
2738 | perf_event_update_userpage(event); |
2739 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2740 | } |
2741 | ||
cdd6c482 IM |
2742 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2743 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2744 | { |
cdd6c482 | 2745 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2746 | |
2747 | if (!ctx->nr_stat) | |
2748 | return; | |
2749 | ||
02ffdbc8 PZ |
2750 | update_context_time(ctx); |
2751 | ||
cdd6c482 IM |
2752 | event = list_first_entry(&ctx->event_list, |
2753 | struct perf_event, event_entry); | |
bfbd3381 | 2754 | |
cdd6c482 IM |
2755 | next_event = list_first_entry(&next_ctx->event_list, |
2756 | struct perf_event, event_entry); | |
bfbd3381 | 2757 | |
cdd6c482 IM |
2758 | while (&event->event_entry != &ctx->event_list && |
2759 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2760 | |
cdd6c482 | 2761 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2762 | |
cdd6c482 IM |
2763 | event = list_next_entry(event, event_entry); |
2764 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2765 | } |
2766 | } | |
2767 | ||
fe4b04fa PZ |
2768 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2769 | struct task_struct *next) | |
0793a61d | 2770 | { |
8dc85d54 | 2771 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2772 | struct perf_event_context *next_ctx; |
5a3126d4 | 2773 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2774 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2775 | int do_switch = 1; |
0793a61d | 2776 | |
108b02cf PZ |
2777 | if (likely(!ctx)) |
2778 | return; | |
10989fb2 | 2779 | |
108b02cf PZ |
2780 | cpuctx = __get_cpu_context(ctx); |
2781 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2782 | return; |
2783 | ||
c93f7669 | 2784 | rcu_read_lock(); |
8dc85d54 | 2785 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2786 | if (!next_ctx) |
2787 | goto unlock; | |
2788 | ||
2789 | parent = rcu_dereference(ctx->parent_ctx); | |
2790 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2791 | ||
2792 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2793 | if (!parent && !next_parent) |
5a3126d4 PZ |
2794 | goto unlock; |
2795 | ||
2796 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2797 | /* |
2798 | * Looks like the two contexts are clones, so we might be | |
2799 | * able to optimize the context switch. We lock both | |
2800 | * contexts and check that they are clones under the | |
2801 | * lock (including re-checking that neither has been | |
2802 | * uncloned in the meantime). It doesn't matter which | |
2803 | * order we take the locks because no other cpu could | |
2804 | * be trying to lock both of these tasks. | |
2805 | */ | |
e625cce1 TG |
2806 | raw_spin_lock(&ctx->lock); |
2807 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2808 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2809 | WRITE_ONCE(ctx->task, next); |
2810 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2811 | |
2812 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2813 | ||
63b6da39 PZ |
2814 | /* |
2815 | * RCU_INIT_POINTER here is safe because we've not | |
2816 | * modified the ctx and the above modification of | |
2817 | * ctx->task and ctx->task_ctx_data are immaterial | |
2818 | * since those values are always verified under | |
2819 | * ctx->lock which we're now holding. | |
2820 | */ | |
2821 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2822 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2823 | ||
c93f7669 | 2824 | do_switch = 0; |
bfbd3381 | 2825 | |
cdd6c482 | 2826 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2827 | } |
e625cce1 TG |
2828 | raw_spin_unlock(&next_ctx->lock); |
2829 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2830 | } |
5a3126d4 | 2831 | unlock: |
c93f7669 | 2832 | rcu_read_unlock(); |
564c2b21 | 2833 | |
c93f7669 | 2834 | if (do_switch) { |
facc4307 | 2835 | raw_spin_lock(&ctx->lock); |
8833d0e2 | 2836 | task_ctx_sched_out(cpuctx, ctx); |
facc4307 | 2837 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2838 | } |
0793a61d TG |
2839 | } |
2840 | ||
e48c1788 PZ |
2841 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2842 | ||
ba532500 YZ |
2843 | void perf_sched_cb_dec(struct pmu *pmu) |
2844 | { | |
e48c1788 PZ |
2845 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2846 | ||
ba532500 | 2847 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2848 | |
2849 | if (!--cpuctx->sched_cb_usage) | |
2850 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2851 | } |
2852 | ||
e48c1788 | 2853 | |
ba532500 YZ |
2854 | void perf_sched_cb_inc(struct pmu *pmu) |
2855 | { | |
e48c1788 PZ |
2856 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2857 | ||
2858 | if (!cpuctx->sched_cb_usage++) | |
2859 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2860 | ||
ba532500 YZ |
2861 | this_cpu_inc(perf_sched_cb_usages); |
2862 | } | |
2863 | ||
2864 | /* | |
2865 | * This function provides the context switch callback to the lower code | |
2866 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2867 | * |
2868 | * This callback is relevant even to per-cpu events; for example multi event | |
2869 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2870 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2871 | */ |
2872 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2873 | struct task_struct *next, | |
2874 | bool sched_in) | |
2875 | { | |
2876 | struct perf_cpu_context *cpuctx; | |
2877 | struct pmu *pmu; | |
ba532500 YZ |
2878 | |
2879 | if (prev == next) | |
2880 | return; | |
2881 | ||
e48c1788 PZ |
2882 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
2883 | pmu = cpuctx->unique_pmu; /* software PMUs will not have sched_task */ | |
ba532500 | 2884 | |
e48c1788 PZ |
2885 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2886 | continue; | |
ba532500 | 2887 | |
e48c1788 PZ |
2888 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
2889 | perf_pmu_disable(pmu); | |
ba532500 | 2890 | |
e48c1788 | 2891 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 2892 | |
e48c1788 PZ |
2893 | perf_pmu_enable(pmu); |
2894 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 2895 | } |
ba532500 YZ |
2896 | } |
2897 | ||
45ac1403 AH |
2898 | static void perf_event_switch(struct task_struct *task, |
2899 | struct task_struct *next_prev, bool sched_in); | |
2900 | ||
8dc85d54 PZ |
2901 | #define for_each_task_context_nr(ctxn) \ |
2902 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2903 | ||
2904 | /* | |
2905 | * Called from scheduler to remove the events of the current task, | |
2906 | * with interrupts disabled. | |
2907 | * | |
2908 | * We stop each event and update the event value in event->count. | |
2909 | * | |
2910 | * This does not protect us against NMI, but disable() | |
2911 | * sets the disabled bit in the control field of event _before_ | |
2912 | * accessing the event control register. If a NMI hits, then it will | |
2913 | * not restart the event. | |
2914 | */ | |
ab0cce56 JO |
2915 | void __perf_event_task_sched_out(struct task_struct *task, |
2916 | struct task_struct *next) | |
8dc85d54 PZ |
2917 | { |
2918 | int ctxn; | |
2919 | ||
ba532500 YZ |
2920 | if (__this_cpu_read(perf_sched_cb_usages)) |
2921 | perf_pmu_sched_task(task, next, false); | |
2922 | ||
45ac1403 AH |
2923 | if (atomic_read(&nr_switch_events)) |
2924 | perf_event_switch(task, next, false); | |
2925 | ||
8dc85d54 PZ |
2926 | for_each_task_context_nr(ctxn) |
2927 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2928 | |
2929 | /* | |
2930 | * if cgroup events exist on this CPU, then we need | |
2931 | * to check if we have to switch out PMU state. | |
2932 | * cgroup event are system-wide mode only | |
2933 | */ | |
4a32fea9 | 2934 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2935 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2936 | } |
2937 | ||
5b0311e1 FW |
2938 | /* |
2939 | * Called with IRQs disabled | |
2940 | */ | |
2941 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2942 | enum event_type_t event_type) | |
2943 | { | |
2944 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2945 | } |
2946 | ||
235c7fc7 | 2947 | static void |
5b0311e1 | 2948 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2949 | struct perf_cpu_context *cpuctx) |
0793a61d | 2950 | { |
cdd6c482 | 2951 | struct perf_event *event; |
0793a61d | 2952 | |
889ff015 FW |
2953 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2954 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2955 | continue; |
5632ab12 | 2956 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2957 | continue; |
2958 | ||
e5d1367f SE |
2959 | /* may need to reset tstamp_enabled */ |
2960 | if (is_cgroup_event(event)) | |
2961 | perf_cgroup_mark_enabled(event, ctx); | |
2962 | ||
8c9ed8e1 | 2963 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2964 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2965 | |
2966 | /* | |
2967 | * If this pinned group hasn't been scheduled, | |
2968 | * put it in error state. | |
2969 | */ | |
cdd6c482 IM |
2970 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2971 | update_group_times(event); | |
2972 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2973 | } |
3b6f9e5c | 2974 | } |
5b0311e1 FW |
2975 | } |
2976 | ||
2977 | static void | |
2978 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2979 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2980 | { |
2981 | struct perf_event *event; | |
2982 | int can_add_hw = 1; | |
3b6f9e5c | 2983 | |
889ff015 FW |
2984 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2985 | /* Ignore events in OFF or ERROR state */ | |
2986 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2987 | continue; |
04289bb9 IM |
2988 | /* |
2989 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2990 | * of events: |
04289bb9 | 2991 | */ |
5632ab12 | 2992 | if (!event_filter_match(event)) |
0793a61d TG |
2993 | continue; |
2994 | ||
e5d1367f SE |
2995 | /* may need to reset tstamp_enabled */ |
2996 | if (is_cgroup_event(event)) | |
2997 | perf_cgroup_mark_enabled(event, ctx); | |
2998 | ||
9ed6060d | 2999 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3000 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3001 | can_add_hw = 0; |
9ed6060d | 3002 | } |
0793a61d | 3003 | } |
5b0311e1 FW |
3004 | } |
3005 | ||
3006 | static void | |
3007 | ctx_sched_in(struct perf_event_context *ctx, | |
3008 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3009 | enum event_type_t event_type, |
3010 | struct task_struct *task) | |
5b0311e1 | 3011 | { |
db24d33e | 3012 | int is_active = ctx->is_active; |
c994d613 PZ |
3013 | u64 now; |
3014 | ||
3015 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3016 | |
5b0311e1 | 3017 | if (likely(!ctx->nr_events)) |
facc4307 | 3018 | return; |
5b0311e1 | 3019 | |
3cbaa590 | 3020 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3021 | if (ctx->task) { |
3022 | if (!is_active) | |
3023 | cpuctx->task_ctx = ctx; | |
3024 | else | |
3025 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3026 | } | |
3027 | ||
3cbaa590 PZ |
3028 | is_active ^= ctx->is_active; /* changed bits */ |
3029 | ||
3030 | if (is_active & EVENT_TIME) { | |
3031 | /* start ctx time */ | |
3032 | now = perf_clock(); | |
3033 | ctx->timestamp = now; | |
3034 | perf_cgroup_set_timestamp(task, ctx); | |
3035 | } | |
3036 | ||
5b0311e1 FW |
3037 | /* |
3038 | * First go through the list and put on any pinned groups | |
3039 | * in order to give them the best chance of going on. | |
3040 | */ | |
3cbaa590 | 3041 | if (is_active & EVENT_PINNED) |
6e37738a | 3042 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3043 | |
3044 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3045 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3046 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3047 | } |
3048 | ||
329c0e01 | 3049 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3050 | enum event_type_t event_type, |
3051 | struct task_struct *task) | |
329c0e01 FW |
3052 | { |
3053 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3054 | ||
e5d1367f | 3055 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3056 | } |
3057 | ||
e5d1367f SE |
3058 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3059 | struct task_struct *task) | |
235c7fc7 | 3060 | { |
108b02cf | 3061 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3062 | |
108b02cf | 3063 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3064 | if (cpuctx->task_ctx == ctx) |
3065 | return; | |
3066 | ||
facc4307 | 3067 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3068 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3069 | /* |
3070 | * We want to keep the following priority order: | |
3071 | * cpu pinned (that don't need to move), task pinned, | |
3072 | * cpu flexible, task flexible. | |
3073 | */ | |
3074 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3075 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3076 | perf_pmu_enable(ctx->pmu); |
3077 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3078 | } |
3079 | ||
8dc85d54 PZ |
3080 | /* |
3081 | * Called from scheduler to add the events of the current task | |
3082 | * with interrupts disabled. | |
3083 | * | |
3084 | * We restore the event value and then enable it. | |
3085 | * | |
3086 | * This does not protect us against NMI, but enable() | |
3087 | * sets the enabled bit in the control field of event _before_ | |
3088 | * accessing the event control register. If a NMI hits, then it will | |
3089 | * keep the event running. | |
3090 | */ | |
ab0cce56 JO |
3091 | void __perf_event_task_sched_in(struct task_struct *prev, |
3092 | struct task_struct *task) | |
8dc85d54 PZ |
3093 | { |
3094 | struct perf_event_context *ctx; | |
3095 | int ctxn; | |
3096 | ||
7e41d177 PZ |
3097 | /* |
3098 | * If cgroup events exist on this CPU, then we need to check if we have | |
3099 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3100 | * | |
3101 | * Since cgroup events are CPU events, we must schedule these in before | |
3102 | * we schedule in the task events. | |
3103 | */ | |
3104 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3105 | perf_cgroup_sched_in(prev, task); | |
3106 | ||
8dc85d54 PZ |
3107 | for_each_task_context_nr(ctxn) { |
3108 | ctx = task->perf_event_ctxp[ctxn]; | |
3109 | if (likely(!ctx)) | |
3110 | continue; | |
3111 | ||
e5d1367f | 3112 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3113 | } |
d010b332 | 3114 | |
45ac1403 AH |
3115 | if (atomic_read(&nr_switch_events)) |
3116 | perf_event_switch(task, prev, true); | |
3117 | ||
ba532500 YZ |
3118 | if (__this_cpu_read(perf_sched_cb_usages)) |
3119 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3120 | } |
3121 | ||
abd50713 PZ |
3122 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3123 | { | |
3124 | u64 frequency = event->attr.sample_freq; | |
3125 | u64 sec = NSEC_PER_SEC; | |
3126 | u64 divisor, dividend; | |
3127 | ||
3128 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3129 | ||
3130 | count_fls = fls64(count); | |
3131 | nsec_fls = fls64(nsec); | |
3132 | frequency_fls = fls64(frequency); | |
3133 | sec_fls = 30; | |
3134 | ||
3135 | /* | |
3136 | * We got @count in @nsec, with a target of sample_freq HZ | |
3137 | * the target period becomes: | |
3138 | * | |
3139 | * @count * 10^9 | |
3140 | * period = ------------------- | |
3141 | * @nsec * sample_freq | |
3142 | * | |
3143 | */ | |
3144 | ||
3145 | /* | |
3146 | * Reduce accuracy by one bit such that @a and @b converge | |
3147 | * to a similar magnitude. | |
3148 | */ | |
fe4b04fa | 3149 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3150 | do { \ |
3151 | if (a##_fls > b##_fls) { \ | |
3152 | a >>= 1; \ | |
3153 | a##_fls--; \ | |
3154 | } else { \ | |
3155 | b >>= 1; \ | |
3156 | b##_fls--; \ | |
3157 | } \ | |
3158 | } while (0) | |
3159 | ||
3160 | /* | |
3161 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3162 | * the other, so that finally we can do a u64/u64 division. | |
3163 | */ | |
3164 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3165 | REDUCE_FLS(nsec, frequency); | |
3166 | REDUCE_FLS(sec, count); | |
3167 | } | |
3168 | ||
3169 | if (count_fls + sec_fls > 64) { | |
3170 | divisor = nsec * frequency; | |
3171 | ||
3172 | while (count_fls + sec_fls > 64) { | |
3173 | REDUCE_FLS(count, sec); | |
3174 | divisor >>= 1; | |
3175 | } | |
3176 | ||
3177 | dividend = count * sec; | |
3178 | } else { | |
3179 | dividend = count * sec; | |
3180 | ||
3181 | while (nsec_fls + frequency_fls > 64) { | |
3182 | REDUCE_FLS(nsec, frequency); | |
3183 | dividend >>= 1; | |
3184 | } | |
3185 | ||
3186 | divisor = nsec * frequency; | |
3187 | } | |
3188 | ||
f6ab91ad PZ |
3189 | if (!divisor) |
3190 | return dividend; | |
3191 | ||
abd50713 PZ |
3192 | return div64_u64(dividend, divisor); |
3193 | } | |
3194 | ||
e050e3f0 SE |
3195 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3196 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3197 | ||
f39d47ff | 3198 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3199 | { |
cdd6c482 | 3200 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3201 | s64 period, sample_period; |
bd2b5b12 PZ |
3202 | s64 delta; |
3203 | ||
abd50713 | 3204 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3205 | |
3206 | delta = (s64)(period - hwc->sample_period); | |
3207 | delta = (delta + 7) / 8; /* low pass filter */ | |
3208 | ||
3209 | sample_period = hwc->sample_period + delta; | |
3210 | ||
3211 | if (!sample_period) | |
3212 | sample_period = 1; | |
3213 | ||
bd2b5b12 | 3214 | hwc->sample_period = sample_period; |
abd50713 | 3215 | |
e7850595 | 3216 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3217 | if (disable) |
3218 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3219 | ||
e7850595 | 3220 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3221 | |
3222 | if (disable) | |
3223 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3224 | } |
bd2b5b12 PZ |
3225 | } |
3226 | ||
e050e3f0 SE |
3227 | /* |
3228 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3229 | * events. At the same time, make sure, having freq events does not change | |
3230 | * the rate of unthrottling as that would introduce bias. | |
3231 | */ | |
3232 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3233 | int needs_unthr) | |
60db5e09 | 3234 | { |
cdd6c482 IM |
3235 | struct perf_event *event; |
3236 | struct hw_perf_event *hwc; | |
e050e3f0 | 3237 | u64 now, period = TICK_NSEC; |
abd50713 | 3238 | s64 delta; |
60db5e09 | 3239 | |
e050e3f0 SE |
3240 | /* |
3241 | * only need to iterate over all events iff: | |
3242 | * - context have events in frequency mode (needs freq adjust) | |
3243 | * - there are events to unthrottle on this cpu | |
3244 | */ | |
3245 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3246 | return; |
3247 | ||
e050e3f0 | 3248 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3249 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3250 | |
03541f8b | 3251 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3252 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3253 | continue; |
3254 | ||
5632ab12 | 3255 | if (!event_filter_match(event)) |
5d27c23d PZ |
3256 | continue; |
3257 | ||
44377277 AS |
3258 | perf_pmu_disable(event->pmu); |
3259 | ||
cdd6c482 | 3260 | hwc = &event->hw; |
6a24ed6c | 3261 | |
ae23bff1 | 3262 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3263 | hwc->interrupts = 0; |
cdd6c482 | 3264 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3265 | event->pmu->start(event, 0); |
a78ac325 PZ |
3266 | } |
3267 | ||
cdd6c482 | 3268 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3269 | goto next; |
60db5e09 | 3270 | |
e050e3f0 SE |
3271 | /* |
3272 | * stop the event and update event->count | |
3273 | */ | |
3274 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3275 | ||
e7850595 | 3276 | now = local64_read(&event->count); |
abd50713 PZ |
3277 | delta = now - hwc->freq_count_stamp; |
3278 | hwc->freq_count_stamp = now; | |
60db5e09 | 3279 | |
e050e3f0 SE |
3280 | /* |
3281 | * restart the event | |
3282 | * reload only if value has changed | |
f39d47ff SE |
3283 | * we have stopped the event so tell that |
3284 | * to perf_adjust_period() to avoid stopping it | |
3285 | * twice. | |
e050e3f0 | 3286 | */ |
abd50713 | 3287 | if (delta > 0) |
f39d47ff | 3288 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3289 | |
3290 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3291 | next: |
3292 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3293 | } |
e050e3f0 | 3294 | |
f39d47ff | 3295 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3296 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3297 | } |
3298 | ||
235c7fc7 | 3299 | /* |
cdd6c482 | 3300 | * Round-robin a context's events: |
235c7fc7 | 3301 | */ |
cdd6c482 | 3302 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3303 | { |
dddd3379 TG |
3304 | /* |
3305 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3306 | * disabled by the inheritance code. | |
3307 | */ | |
3308 | if (!ctx->rotate_disable) | |
3309 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3310 | } |
3311 | ||
9e630205 | 3312 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3313 | { |
8dc85d54 | 3314 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3315 | int rotate = 0; |
7fc23a53 | 3316 | |
b5ab4cd5 | 3317 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3318 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3319 | rotate = 1; | |
3320 | } | |
235c7fc7 | 3321 | |
8dc85d54 | 3322 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3323 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3324 | if (ctx->nr_events != ctx->nr_active) |
3325 | rotate = 1; | |
3326 | } | |
9717e6cd | 3327 | |
e050e3f0 | 3328 | if (!rotate) |
0f5a2601 PZ |
3329 | goto done; |
3330 | ||
facc4307 | 3331 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3332 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3333 | |
e050e3f0 SE |
3334 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3335 | if (ctx) | |
3336 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3337 | |
e050e3f0 SE |
3338 | rotate_ctx(&cpuctx->ctx); |
3339 | if (ctx) | |
3340 | rotate_ctx(ctx); | |
235c7fc7 | 3341 | |
e050e3f0 | 3342 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3343 | |
0f5a2601 PZ |
3344 | perf_pmu_enable(cpuctx->ctx.pmu); |
3345 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3346 | done: |
9e630205 SE |
3347 | |
3348 | return rotate; | |
e9d2b064 PZ |
3349 | } |
3350 | ||
3351 | void perf_event_task_tick(void) | |
3352 | { | |
2fde4f94 MR |
3353 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3354 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3355 | int throttled; |
b5ab4cd5 | 3356 | |
e9d2b064 PZ |
3357 | WARN_ON(!irqs_disabled()); |
3358 | ||
e050e3f0 SE |
3359 | __this_cpu_inc(perf_throttled_seq); |
3360 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3361 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3362 | |
2fde4f94 | 3363 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3364 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3365 | } |
3366 | ||
889ff015 FW |
3367 | static int event_enable_on_exec(struct perf_event *event, |
3368 | struct perf_event_context *ctx) | |
3369 | { | |
3370 | if (!event->attr.enable_on_exec) | |
3371 | return 0; | |
3372 | ||
3373 | event->attr.enable_on_exec = 0; | |
3374 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3375 | return 0; | |
3376 | ||
1d9b482e | 3377 | __perf_event_mark_enabled(event); |
889ff015 FW |
3378 | |
3379 | return 1; | |
3380 | } | |
3381 | ||
57e7986e | 3382 | /* |
cdd6c482 | 3383 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3384 | * This expects task == current. |
3385 | */ | |
c1274499 | 3386 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3387 | { |
c1274499 | 3388 | struct perf_event_context *ctx, *clone_ctx = NULL; |
3e349507 | 3389 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3390 | struct perf_event *event; |
57e7986e PM |
3391 | unsigned long flags; |
3392 | int enabled = 0; | |
3393 | ||
3394 | local_irq_save(flags); | |
c1274499 | 3395 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3396 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3397 | goto out; |
3398 | ||
3e349507 PZ |
3399 | cpuctx = __get_cpu_context(ctx); |
3400 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3401 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
3e349507 PZ |
3402 | list_for_each_entry(event, &ctx->event_list, event_entry) |
3403 | enabled |= event_enable_on_exec(event, ctx); | |
57e7986e PM |
3404 | |
3405 | /* | |
3e349507 | 3406 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3407 | */ |
3e349507 | 3408 | if (enabled) { |
211de6eb | 3409 | clone_ctx = unclone_ctx(ctx); |
3e349507 PZ |
3410 | ctx_resched(cpuctx, ctx); |
3411 | } | |
3412 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3413 | |
9ed6060d | 3414 | out: |
57e7986e | 3415 | local_irq_restore(flags); |
211de6eb PZ |
3416 | |
3417 | if (clone_ctx) | |
3418 | put_ctx(clone_ctx); | |
57e7986e PM |
3419 | } |
3420 | ||
0492d4c5 PZ |
3421 | struct perf_read_data { |
3422 | struct perf_event *event; | |
3423 | bool group; | |
7d88962e | 3424 | int ret; |
0492d4c5 PZ |
3425 | }; |
3426 | ||
0793a61d | 3427 | /* |
cdd6c482 | 3428 | * Cross CPU call to read the hardware event |
0793a61d | 3429 | */ |
cdd6c482 | 3430 | static void __perf_event_read(void *info) |
0793a61d | 3431 | { |
0492d4c5 PZ |
3432 | struct perf_read_data *data = info; |
3433 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3434 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3435 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3436 | struct pmu *pmu = event->pmu; |
621a01ea | 3437 | |
e1ac3614 PM |
3438 | /* |
3439 | * If this is a task context, we need to check whether it is | |
3440 | * the current task context of this cpu. If not it has been | |
3441 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3442 | * event->count would have been updated to a recent sample |
3443 | * when the event was scheduled out. | |
e1ac3614 PM |
3444 | */ |
3445 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3446 | return; | |
3447 | ||
e625cce1 | 3448 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3449 | if (ctx->is_active) { |
542e72fc | 3450 | update_context_time(ctx); |
e5d1367f SE |
3451 | update_cgrp_time_from_event(event); |
3452 | } | |
0492d4c5 | 3453 | |
cdd6c482 | 3454 | update_event_times(event); |
4a00c16e SB |
3455 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3456 | goto unlock; | |
0492d4c5 | 3457 | |
4a00c16e SB |
3458 | if (!data->group) { |
3459 | pmu->read(event); | |
3460 | data->ret = 0; | |
0492d4c5 | 3461 | goto unlock; |
4a00c16e SB |
3462 | } |
3463 | ||
3464 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3465 | ||
3466 | pmu->read(event); | |
0492d4c5 PZ |
3467 | |
3468 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3469 | update_event_times(sub); | |
4a00c16e SB |
3470 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3471 | /* | |
3472 | * Use sibling's PMU rather than @event's since | |
3473 | * sibling could be on different (eg: software) PMU. | |
3474 | */ | |
0492d4c5 | 3475 | sub->pmu->read(sub); |
4a00c16e | 3476 | } |
0492d4c5 | 3477 | } |
4a00c16e SB |
3478 | |
3479 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3480 | |
3481 | unlock: | |
e625cce1 | 3482 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3483 | } |
3484 | ||
b5e58793 PZ |
3485 | static inline u64 perf_event_count(struct perf_event *event) |
3486 | { | |
eacd3ecc MF |
3487 | if (event->pmu->count) |
3488 | return event->pmu->count(event); | |
3489 | ||
3490 | return __perf_event_count(event); | |
b5e58793 PZ |
3491 | } |
3492 | ||
ffe8690c KX |
3493 | /* |
3494 | * NMI-safe method to read a local event, that is an event that | |
3495 | * is: | |
3496 | * - either for the current task, or for this CPU | |
3497 | * - does not have inherit set, for inherited task events | |
3498 | * will not be local and we cannot read them atomically | |
3499 | * - must not have a pmu::count method | |
3500 | */ | |
3501 | u64 perf_event_read_local(struct perf_event *event) | |
3502 | { | |
3503 | unsigned long flags; | |
3504 | u64 val; | |
3505 | ||
3506 | /* | |
3507 | * Disabling interrupts avoids all counter scheduling (context | |
3508 | * switches, timer based rotation and IPIs). | |
3509 | */ | |
3510 | local_irq_save(flags); | |
3511 | ||
3512 | /* If this is a per-task event, it must be for current */ | |
3513 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3514 | event->hw.target != current); | |
3515 | ||
3516 | /* If this is a per-CPU event, it must be for this CPU */ | |
3517 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3518 | event->cpu != smp_processor_id()); | |
3519 | ||
3520 | /* | |
3521 | * It must not be an event with inherit set, we cannot read | |
3522 | * all child counters from atomic context. | |
3523 | */ | |
3524 | WARN_ON_ONCE(event->attr.inherit); | |
3525 | ||
3526 | /* | |
3527 | * It must not have a pmu::count method, those are not | |
3528 | * NMI safe. | |
3529 | */ | |
3530 | WARN_ON_ONCE(event->pmu->count); | |
3531 | ||
3532 | /* | |
3533 | * If the event is currently on this CPU, its either a per-task event, | |
3534 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3535 | * oncpu == -1). | |
3536 | */ | |
3537 | if (event->oncpu == smp_processor_id()) | |
3538 | event->pmu->read(event); | |
3539 | ||
3540 | val = local64_read(&event->count); | |
3541 | local_irq_restore(flags); | |
3542 | ||
3543 | return val; | |
3544 | } | |
3545 | ||
7d88962e | 3546 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3547 | { |
7d88962e SB |
3548 | int ret = 0; |
3549 | ||
0793a61d | 3550 | /* |
cdd6c482 IM |
3551 | * If event is enabled and currently active on a CPU, update the |
3552 | * value in the event structure: | |
0793a61d | 3553 | */ |
cdd6c482 | 3554 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3555 | struct perf_read_data data = { |
3556 | .event = event, | |
3557 | .group = group, | |
7d88962e | 3558 | .ret = 0, |
0492d4c5 | 3559 | }; |
71e7bc2b DCC |
3560 | ret = smp_call_function_single(event->oncpu, __perf_event_read, &data, 1); |
3561 | /* The event must have been read from an online CPU: */ | |
3562 | WARN_ON_ONCE(ret); | |
3563 | ret = ret ? : data.ret; | |
cdd6c482 | 3564 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3565 | struct perf_event_context *ctx = event->ctx; |
3566 | unsigned long flags; | |
3567 | ||
e625cce1 | 3568 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3569 | /* |
3570 | * may read while context is not active | |
3571 | * (e.g., thread is blocked), in that case | |
3572 | * we cannot update context time | |
3573 | */ | |
e5d1367f | 3574 | if (ctx->is_active) { |
c530ccd9 | 3575 | update_context_time(ctx); |
e5d1367f SE |
3576 | update_cgrp_time_from_event(event); |
3577 | } | |
0492d4c5 PZ |
3578 | if (group) |
3579 | update_group_times(event); | |
3580 | else | |
3581 | update_event_times(event); | |
e625cce1 | 3582 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3583 | } |
7d88962e SB |
3584 | |
3585 | return ret; | |
0793a61d TG |
3586 | } |
3587 | ||
a63eaf34 | 3588 | /* |
cdd6c482 | 3589 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3590 | */ |
eb184479 | 3591 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3592 | { |
e625cce1 | 3593 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3594 | mutex_init(&ctx->mutex); |
2fde4f94 | 3595 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3596 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3597 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3598 | INIT_LIST_HEAD(&ctx->event_list); |
3599 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3600 | } |
3601 | ||
3602 | static struct perf_event_context * | |
3603 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3604 | { | |
3605 | struct perf_event_context *ctx; | |
3606 | ||
3607 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3608 | if (!ctx) | |
3609 | return NULL; | |
3610 | ||
3611 | __perf_event_init_context(ctx); | |
3612 | if (task) { | |
3613 | ctx->task = task; | |
3614 | get_task_struct(task); | |
0793a61d | 3615 | } |
eb184479 PZ |
3616 | ctx->pmu = pmu; |
3617 | ||
3618 | return ctx; | |
a63eaf34 PM |
3619 | } |
3620 | ||
2ebd4ffb MH |
3621 | static struct task_struct * |
3622 | find_lively_task_by_vpid(pid_t vpid) | |
3623 | { | |
3624 | struct task_struct *task; | |
0793a61d TG |
3625 | |
3626 | rcu_read_lock(); | |
2ebd4ffb | 3627 | if (!vpid) |
0793a61d TG |
3628 | task = current; |
3629 | else | |
2ebd4ffb | 3630 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3631 | if (task) |
3632 | get_task_struct(task); | |
3633 | rcu_read_unlock(); | |
3634 | ||
3635 | if (!task) | |
3636 | return ERR_PTR(-ESRCH); | |
3637 | ||
2ebd4ffb | 3638 | return task; |
2ebd4ffb MH |
3639 | } |
3640 | ||
fe4b04fa PZ |
3641 | /* |
3642 | * Returns a matching context with refcount and pincount. | |
3643 | */ | |
108b02cf | 3644 | static struct perf_event_context * |
4af57ef2 YZ |
3645 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3646 | struct perf_event *event) | |
0793a61d | 3647 | { |
211de6eb | 3648 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3649 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3650 | void *task_ctx_data = NULL; |
25346b93 | 3651 | unsigned long flags; |
8dc85d54 | 3652 | int ctxn, err; |
4af57ef2 | 3653 | int cpu = event->cpu; |
0793a61d | 3654 | |
22a4ec72 | 3655 | if (!task) { |
cdd6c482 | 3656 | /* Must be root to operate on a CPU event: */ |
0764771d | 3657 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3658 | return ERR_PTR(-EACCES); |
3659 | ||
0793a61d | 3660 | /* |
cdd6c482 | 3661 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3662 | * offline CPU and activate it when the CPU comes up, but |
3663 | * that's for later. | |
3664 | */ | |
f6325e30 | 3665 | if (!cpu_online(cpu)) |
0793a61d TG |
3666 | return ERR_PTR(-ENODEV); |
3667 | ||
108b02cf | 3668 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3669 | ctx = &cpuctx->ctx; |
c93f7669 | 3670 | get_ctx(ctx); |
fe4b04fa | 3671 | ++ctx->pin_count; |
0793a61d | 3672 | |
0793a61d TG |
3673 | return ctx; |
3674 | } | |
3675 | ||
8dc85d54 PZ |
3676 | err = -EINVAL; |
3677 | ctxn = pmu->task_ctx_nr; | |
3678 | if (ctxn < 0) | |
3679 | goto errout; | |
3680 | ||
4af57ef2 YZ |
3681 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3682 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3683 | if (!task_ctx_data) { | |
3684 | err = -ENOMEM; | |
3685 | goto errout; | |
3686 | } | |
3687 | } | |
3688 | ||
9ed6060d | 3689 | retry: |
8dc85d54 | 3690 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3691 | if (ctx) { |
211de6eb | 3692 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3693 | ++ctx->pin_count; |
4af57ef2 YZ |
3694 | |
3695 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3696 | ctx->task_ctx_data = task_ctx_data; | |
3697 | task_ctx_data = NULL; | |
3698 | } | |
e625cce1 | 3699 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3700 | |
3701 | if (clone_ctx) | |
3702 | put_ctx(clone_ctx); | |
9137fb28 | 3703 | } else { |
eb184479 | 3704 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3705 | err = -ENOMEM; |
3706 | if (!ctx) | |
3707 | goto errout; | |
eb184479 | 3708 | |
4af57ef2 YZ |
3709 | if (task_ctx_data) { |
3710 | ctx->task_ctx_data = task_ctx_data; | |
3711 | task_ctx_data = NULL; | |
3712 | } | |
3713 | ||
dbe08d82 ON |
3714 | err = 0; |
3715 | mutex_lock(&task->perf_event_mutex); | |
3716 | /* | |
3717 | * If it has already passed perf_event_exit_task(). | |
3718 | * we must see PF_EXITING, it takes this mutex too. | |
3719 | */ | |
3720 | if (task->flags & PF_EXITING) | |
3721 | err = -ESRCH; | |
3722 | else if (task->perf_event_ctxp[ctxn]) | |
3723 | err = -EAGAIN; | |
fe4b04fa | 3724 | else { |
9137fb28 | 3725 | get_ctx(ctx); |
fe4b04fa | 3726 | ++ctx->pin_count; |
dbe08d82 | 3727 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3728 | } |
dbe08d82 ON |
3729 | mutex_unlock(&task->perf_event_mutex); |
3730 | ||
3731 | if (unlikely(err)) { | |
9137fb28 | 3732 | put_ctx(ctx); |
dbe08d82 ON |
3733 | |
3734 | if (err == -EAGAIN) | |
3735 | goto retry; | |
3736 | goto errout; | |
a63eaf34 PM |
3737 | } |
3738 | } | |
3739 | ||
4af57ef2 | 3740 | kfree(task_ctx_data); |
0793a61d | 3741 | return ctx; |
c93f7669 | 3742 | |
9ed6060d | 3743 | errout: |
4af57ef2 | 3744 | kfree(task_ctx_data); |
c93f7669 | 3745 | return ERR_PTR(err); |
0793a61d TG |
3746 | } |
3747 | ||
6fb2915d | 3748 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3749 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3750 | |
cdd6c482 | 3751 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3752 | { |
cdd6c482 | 3753 | struct perf_event *event; |
592903cd | 3754 | |
cdd6c482 IM |
3755 | event = container_of(head, struct perf_event, rcu_head); |
3756 | if (event->ns) | |
3757 | put_pid_ns(event->ns); | |
6fb2915d | 3758 | perf_event_free_filter(event); |
cdd6c482 | 3759 | kfree(event); |
592903cd PZ |
3760 | } |
3761 | ||
b69cf536 PZ |
3762 | static void ring_buffer_attach(struct perf_event *event, |
3763 | struct ring_buffer *rb); | |
925d519a | 3764 | |
f2fb6bef KL |
3765 | static void detach_sb_event(struct perf_event *event) |
3766 | { | |
3767 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3768 | ||
3769 | raw_spin_lock(&pel->lock); | |
3770 | list_del_rcu(&event->sb_list); | |
3771 | raw_spin_unlock(&pel->lock); | |
3772 | } | |
3773 | ||
a4f144eb | 3774 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3775 | { |
a4f144eb DCC |
3776 | struct perf_event_attr *attr = &event->attr; |
3777 | ||
f2fb6bef | 3778 | if (event->parent) |
a4f144eb | 3779 | return false; |
f2fb6bef KL |
3780 | |
3781 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3782 | return false; |
f2fb6bef | 3783 | |
a4f144eb DCC |
3784 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3785 | attr->comm || attr->comm_exec || | |
3786 | attr->task || | |
3787 | attr->context_switch) | |
3788 | return true; | |
3789 | return false; | |
3790 | } | |
3791 | ||
3792 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3793 | { | |
3794 | if (is_sb_event(event)) | |
3795 | detach_sb_event(event); | |
f2fb6bef KL |
3796 | } |
3797 | ||
4beb31f3 | 3798 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3799 | { |
4beb31f3 FW |
3800 | if (event->parent) |
3801 | return; | |
3802 | ||
4beb31f3 FW |
3803 | if (is_cgroup_event(event)) |
3804 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3805 | } | |
925d519a | 3806 | |
555e0c1e FW |
3807 | #ifdef CONFIG_NO_HZ_FULL |
3808 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3809 | #endif | |
3810 | ||
3811 | static void unaccount_freq_event_nohz(void) | |
3812 | { | |
3813 | #ifdef CONFIG_NO_HZ_FULL | |
3814 | spin_lock(&nr_freq_lock); | |
3815 | if (atomic_dec_and_test(&nr_freq_events)) | |
3816 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3817 | spin_unlock(&nr_freq_lock); | |
3818 | #endif | |
3819 | } | |
3820 | ||
3821 | static void unaccount_freq_event(void) | |
3822 | { | |
3823 | if (tick_nohz_full_enabled()) | |
3824 | unaccount_freq_event_nohz(); | |
3825 | else | |
3826 | atomic_dec(&nr_freq_events); | |
3827 | } | |
3828 | ||
4beb31f3 FW |
3829 | static void unaccount_event(struct perf_event *event) |
3830 | { | |
25432ae9 PZ |
3831 | bool dec = false; |
3832 | ||
4beb31f3 FW |
3833 | if (event->parent) |
3834 | return; | |
3835 | ||
3836 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3837 | dec = true; |
4beb31f3 FW |
3838 | if (event->attr.mmap || event->attr.mmap_data) |
3839 | atomic_dec(&nr_mmap_events); | |
3840 | if (event->attr.comm) | |
3841 | atomic_dec(&nr_comm_events); | |
3842 | if (event->attr.task) | |
3843 | atomic_dec(&nr_task_events); | |
948b26b6 | 3844 | if (event->attr.freq) |
555e0c1e | 3845 | unaccount_freq_event(); |
45ac1403 | 3846 | if (event->attr.context_switch) { |
25432ae9 | 3847 | dec = true; |
45ac1403 AH |
3848 | atomic_dec(&nr_switch_events); |
3849 | } | |
4beb31f3 | 3850 | if (is_cgroup_event(event)) |
25432ae9 | 3851 | dec = true; |
4beb31f3 | 3852 | if (has_branch_stack(event)) |
25432ae9 PZ |
3853 | dec = true; |
3854 | ||
9107c89e PZ |
3855 | if (dec) { |
3856 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
3857 | schedule_delayed_work(&perf_sched_work, HZ); | |
3858 | } | |
4beb31f3 FW |
3859 | |
3860 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
3861 | |
3862 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 3863 | } |
925d519a | 3864 | |
9107c89e PZ |
3865 | static void perf_sched_delayed(struct work_struct *work) |
3866 | { | |
3867 | mutex_lock(&perf_sched_mutex); | |
3868 | if (atomic_dec_and_test(&perf_sched_count)) | |
3869 | static_branch_disable(&perf_sched_events); | |
3870 | mutex_unlock(&perf_sched_mutex); | |
3871 | } | |
3872 | ||
bed5b25a AS |
3873 | /* |
3874 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3875 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3876 | * at a time, so we disallow creating events that might conflict, namely: | |
3877 | * | |
3878 | * 1) cpu-wide events in the presence of per-task events, | |
3879 | * 2) per-task events in the presence of cpu-wide events, | |
3880 | * 3) two matching events on the same context. | |
3881 | * | |
3882 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 3883 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
3884 | */ |
3885 | static int exclusive_event_init(struct perf_event *event) | |
3886 | { | |
3887 | struct pmu *pmu = event->pmu; | |
3888 | ||
3889 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3890 | return 0; | |
3891 | ||
3892 | /* | |
3893 | * Prevent co-existence of per-task and cpu-wide events on the | |
3894 | * same exclusive pmu. | |
3895 | * | |
3896 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3897 | * events on this "exclusive" pmu, positive means there are | |
3898 | * per-task events. | |
3899 | * | |
3900 | * Since this is called in perf_event_alloc() path, event::ctx | |
3901 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3902 | * to mean "per-task event", because unlike other attach states it | |
3903 | * never gets cleared. | |
3904 | */ | |
3905 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3906 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3907 | return -EBUSY; | |
3908 | } else { | |
3909 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
3910 | return -EBUSY; | |
3911 | } | |
3912 | ||
3913 | return 0; | |
3914 | } | |
3915 | ||
3916 | static void exclusive_event_destroy(struct perf_event *event) | |
3917 | { | |
3918 | struct pmu *pmu = event->pmu; | |
3919 | ||
3920 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3921 | return; | |
3922 | ||
3923 | /* see comment in exclusive_event_init() */ | |
3924 | if (event->attach_state & PERF_ATTACH_TASK) | |
3925 | atomic_dec(&pmu->exclusive_cnt); | |
3926 | else | |
3927 | atomic_inc(&pmu->exclusive_cnt); | |
3928 | } | |
3929 | ||
3930 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
3931 | { | |
3932 | if ((e1->pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && | |
3933 | (e1->cpu == e2->cpu || | |
3934 | e1->cpu == -1 || | |
3935 | e2->cpu == -1)) | |
3936 | return true; | |
3937 | return false; | |
3938 | } | |
3939 | ||
3940 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
3941 | static bool exclusive_event_installable(struct perf_event *event, | |
3942 | struct perf_event_context *ctx) | |
3943 | { | |
3944 | struct perf_event *iter_event; | |
3945 | struct pmu *pmu = event->pmu; | |
3946 | ||
3947 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3948 | return true; | |
3949 | ||
3950 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
3951 | if (exclusive_event_match(iter_event, event)) | |
3952 | return false; | |
3953 | } | |
3954 | ||
3955 | return true; | |
3956 | } | |
3957 | ||
375637bc AS |
3958 | static void perf_addr_filters_splice(struct perf_event *event, |
3959 | struct list_head *head); | |
3960 | ||
683ede43 | 3961 | static void _free_event(struct perf_event *event) |
f1600952 | 3962 | { |
e360adbe | 3963 | irq_work_sync(&event->pending); |
925d519a | 3964 | |
4beb31f3 | 3965 | unaccount_event(event); |
9ee318a7 | 3966 | |
76369139 | 3967 | if (event->rb) { |
9bb5d40c PZ |
3968 | /* |
3969 | * Can happen when we close an event with re-directed output. | |
3970 | * | |
3971 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
3972 | * over us; possibly making our ring_buffer_put() the last. | |
3973 | */ | |
3974 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 3975 | ring_buffer_attach(event, NULL); |
9bb5d40c | 3976 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
3977 | } |
3978 | ||
e5d1367f SE |
3979 | if (is_cgroup_event(event)) |
3980 | perf_detach_cgroup(event); | |
3981 | ||
a0733e69 PZ |
3982 | if (!event->parent) { |
3983 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
3984 | put_callchain_buffers(); | |
3985 | } | |
3986 | ||
3987 | perf_event_free_bpf_prog(event); | |
375637bc AS |
3988 | perf_addr_filters_splice(event, NULL); |
3989 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
3990 | |
3991 | if (event->destroy) | |
3992 | event->destroy(event); | |
3993 | ||
3994 | if (event->ctx) | |
3995 | put_ctx(event->ctx); | |
3996 | ||
62a92c8f AS |
3997 | exclusive_event_destroy(event); |
3998 | module_put(event->pmu->module); | |
a0733e69 PZ |
3999 | |
4000 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4001 | } |
4002 | ||
683ede43 PZ |
4003 | /* |
4004 | * Used to free events which have a known refcount of 1, such as in error paths | |
4005 | * where the event isn't exposed yet and inherited events. | |
4006 | */ | |
4007 | static void free_event(struct perf_event *event) | |
0793a61d | 4008 | { |
683ede43 PZ |
4009 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4010 | "unexpected event refcount: %ld; ptr=%p\n", | |
4011 | atomic_long_read(&event->refcount), event)) { | |
4012 | /* leak to avoid use-after-free */ | |
4013 | return; | |
4014 | } | |
0793a61d | 4015 | |
683ede43 | 4016 | _free_event(event); |
0793a61d TG |
4017 | } |
4018 | ||
a66a3052 | 4019 | /* |
f8697762 | 4020 | * Remove user event from the owner task. |
a66a3052 | 4021 | */ |
f8697762 | 4022 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4023 | { |
8882135b | 4024 | struct task_struct *owner; |
fb0459d7 | 4025 | |
8882135b | 4026 | rcu_read_lock(); |
8882135b | 4027 | /* |
f47c02c0 PZ |
4028 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4029 | * observe !owner it means the list deletion is complete and we can | |
4030 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4031 | * owner->perf_event_mutex. |
4032 | */ | |
f47c02c0 | 4033 | owner = lockless_dereference(event->owner); |
8882135b PZ |
4034 | if (owner) { |
4035 | /* | |
4036 | * Since delayed_put_task_struct() also drops the last | |
4037 | * task reference we can safely take a new reference | |
4038 | * while holding the rcu_read_lock(). | |
4039 | */ | |
4040 | get_task_struct(owner); | |
4041 | } | |
4042 | rcu_read_unlock(); | |
4043 | ||
4044 | if (owner) { | |
f63a8daa PZ |
4045 | /* |
4046 | * If we're here through perf_event_exit_task() we're already | |
4047 | * holding ctx->mutex which would be an inversion wrt. the | |
4048 | * normal lock order. | |
4049 | * | |
4050 | * However we can safely take this lock because its the child | |
4051 | * ctx->mutex. | |
4052 | */ | |
4053 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4054 | ||
8882135b PZ |
4055 | /* |
4056 | * We have to re-check the event->owner field, if it is cleared | |
4057 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4058 | * ensured they're done, and we can proceed with freeing the | |
4059 | * event. | |
4060 | */ | |
f47c02c0 | 4061 | if (event->owner) { |
8882135b | 4062 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4063 | smp_store_release(&event->owner, NULL); |
4064 | } | |
8882135b PZ |
4065 | mutex_unlock(&owner->perf_event_mutex); |
4066 | put_task_struct(owner); | |
4067 | } | |
f8697762 JO |
4068 | } |
4069 | ||
f8697762 JO |
4070 | static void put_event(struct perf_event *event) |
4071 | { | |
f8697762 JO |
4072 | if (!atomic_long_dec_and_test(&event->refcount)) |
4073 | return; | |
4074 | ||
c6e5b732 PZ |
4075 | _free_event(event); |
4076 | } | |
4077 | ||
4078 | /* | |
4079 | * Kill an event dead; while event:refcount will preserve the event | |
4080 | * object, it will not preserve its functionality. Once the last 'user' | |
4081 | * gives up the object, we'll destroy the thing. | |
4082 | */ | |
4083 | int perf_event_release_kernel(struct perf_event *event) | |
4084 | { | |
a4f4bb6d | 4085 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4086 | struct perf_event *child, *tmp; |
4087 | ||
a4f4bb6d PZ |
4088 | /* |
4089 | * If we got here through err_file: fput(event_file); we will not have | |
4090 | * attached to a context yet. | |
4091 | */ | |
4092 | if (!ctx) { | |
4093 | WARN_ON_ONCE(event->attach_state & | |
4094 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4095 | goto no_ctx; | |
4096 | } | |
4097 | ||
f8697762 JO |
4098 | if (!is_kernel_event(event)) |
4099 | perf_remove_from_owner(event); | |
8882135b | 4100 | |
5fa7c8ec | 4101 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4102 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4103 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4104 | |
a69b0ca4 | 4105 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4106 | /* |
a69b0ca4 PZ |
4107 | * Mark this even as STATE_DEAD, there is no external reference to it |
4108 | * anymore. | |
683ede43 | 4109 | * |
a69b0ca4 PZ |
4110 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4111 | * also see this, most importantly inherit_event() which will avoid | |
4112 | * placing more children on the list. | |
683ede43 | 4113 | * |
c6e5b732 PZ |
4114 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4115 | * child events. | |
683ede43 | 4116 | */ |
a69b0ca4 PZ |
4117 | event->state = PERF_EVENT_STATE_DEAD; |
4118 | raw_spin_unlock_irq(&ctx->lock); | |
4119 | ||
4120 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4121 | |
c6e5b732 PZ |
4122 | again: |
4123 | mutex_lock(&event->child_mutex); | |
4124 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4125 | |
c6e5b732 PZ |
4126 | /* |
4127 | * Cannot change, child events are not migrated, see the | |
4128 | * comment with perf_event_ctx_lock_nested(). | |
4129 | */ | |
4130 | ctx = lockless_dereference(child->ctx); | |
4131 | /* | |
4132 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4133 | * through hoops. We start by grabbing a reference on the ctx. | |
4134 | * | |
4135 | * Since the event cannot get freed while we hold the | |
4136 | * child_mutex, the context must also exist and have a !0 | |
4137 | * reference count. | |
4138 | */ | |
4139 | get_ctx(ctx); | |
4140 | ||
4141 | /* | |
4142 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4143 | * acquire ctx::mutex without fear of it going away. Then we | |
4144 | * can re-acquire child_mutex. | |
4145 | */ | |
4146 | mutex_unlock(&event->child_mutex); | |
4147 | mutex_lock(&ctx->mutex); | |
4148 | mutex_lock(&event->child_mutex); | |
4149 | ||
4150 | /* | |
4151 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4152 | * state, if child is still the first entry, it didn't get freed | |
4153 | * and we can continue doing so. | |
4154 | */ | |
4155 | tmp = list_first_entry_or_null(&event->child_list, | |
4156 | struct perf_event, child_list); | |
4157 | if (tmp == child) { | |
4158 | perf_remove_from_context(child, DETACH_GROUP); | |
4159 | list_del(&child->child_list); | |
4160 | free_event(child); | |
4161 | /* | |
4162 | * This matches the refcount bump in inherit_event(); | |
4163 | * this can't be the last reference. | |
4164 | */ | |
4165 | put_event(event); | |
4166 | } | |
4167 | ||
4168 | mutex_unlock(&event->child_mutex); | |
4169 | mutex_unlock(&ctx->mutex); | |
4170 | put_ctx(ctx); | |
4171 | goto again; | |
4172 | } | |
4173 | mutex_unlock(&event->child_mutex); | |
4174 | ||
a4f4bb6d PZ |
4175 | no_ctx: |
4176 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4177 | return 0; |
4178 | } | |
4179 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4180 | ||
8b10c5e2 PZ |
4181 | /* |
4182 | * Called when the last reference to the file is gone. | |
4183 | */ | |
a6fa941d AV |
4184 | static int perf_release(struct inode *inode, struct file *file) |
4185 | { | |
c6e5b732 | 4186 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4187 | return 0; |
fb0459d7 | 4188 | } |
fb0459d7 | 4189 | |
59ed446f | 4190 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4191 | { |
cdd6c482 | 4192 | struct perf_event *child; |
e53c0994 PZ |
4193 | u64 total = 0; |
4194 | ||
59ed446f PZ |
4195 | *enabled = 0; |
4196 | *running = 0; | |
4197 | ||
6f10581a | 4198 | mutex_lock(&event->child_mutex); |
01add3ea | 4199 | |
7d88962e | 4200 | (void)perf_event_read(event, false); |
01add3ea SB |
4201 | total += perf_event_count(event); |
4202 | ||
59ed446f PZ |
4203 | *enabled += event->total_time_enabled + |
4204 | atomic64_read(&event->child_total_time_enabled); | |
4205 | *running += event->total_time_running + | |
4206 | atomic64_read(&event->child_total_time_running); | |
4207 | ||
4208 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4209 | (void)perf_event_read(child, false); |
01add3ea | 4210 | total += perf_event_count(child); |
59ed446f PZ |
4211 | *enabled += child->total_time_enabled; |
4212 | *running += child->total_time_running; | |
4213 | } | |
6f10581a | 4214 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4215 | |
4216 | return total; | |
4217 | } | |
fb0459d7 | 4218 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4219 | |
7d88962e | 4220 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4221 | u64 read_format, u64 *values) |
3dab77fb | 4222 | { |
fa8c2693 PZ |
4223 | struct perf_event *sub; |
4224 | int n = 1; /* skip @nr */ | |
7d88962e | 4225 | int ret; |
f63a8daa | 4226 | |
7d88962e SB |
4227 | ret = perf_event_read(leader, true); |
4228 | if (ret) | |
4229 | return ret; | |
abf4868b | 4230 | |
fa8c2693 PZ |
4231 | /* |
4232 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4233 | * will be identical to those of the leader, so we only publish one | |
4234 | * set. | |
4235 | */ | |
4236 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4237 | values[n++] += leader->total_time_enabled + | |
4238 | atomic64_read(&leader->child_total_time_enabled); | |
4239 | } | |
3dab77fb | 4240 | |
fa8c2693 PZ |
4241 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4242 | values[n++] += leader->total_time_running + | |
4243 | atomic64_read(&leader->child_total_time_running); | |
4244 | } | |
4245 | ||
4246 | /* | |
4247 | * Write {count,id} tuples for every sibling. | |
4248 | */ | |
4249 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4250 | if (read_format & PERF_FORMAT_ID) |
4251 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4252 | |
fa8c2693 PZ |
4253 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4254 | values[n++] += perf_event_count(sub); | |
4255 | if (read_format & PERF_FORMAT_ID) | |
4256 | values[n++] = primary_event_id(sub); | |
4257 | } | |
7d88962e SB |
4258 | |
4259 | return 0; | |
fa8c2693 | 4260 | } |
3dab77fb | 4261 | |
fa8c2693 PZ |
4262 | static int perf_read_group(struct perf_event *event, |
4263 | u64 read_format, char __user *buf) | |
4264 | { | |
4265 | struct perf_event *leader = event->group_leader, *child; | |
4266 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4267 | int ret; |
fa8c2693 | 4268 | u64 *values; |
3dab77fb | 4269 | |
fa8c2693 | 4270 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4271 | |
fa8c2693 PZ |
4272 | values = kzalloc(event->read_size, GFP_KERNEL); |
4273 | if (!values) | |
4274 | return -ENOMEM; | |
3dab77fb | 4275 | |
fa8c2693 PZ |
4276 | values[0] = 1 + leader->nr_siblings; |
4277 | ||
4278 | /* | |
4279 | * By locking the child_mutex of the leader we effectively | |
4280 | * lock the child list of all siblings.. XXX explain how. | |
4281 | */ | |
4282 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4283 | |
7d88962e SB |
4284 | ret = __perf_read_group_add(leader, read_format, values); |
4285 | if (ret) | |
4286 | goto unlock; | |
4287 | ||
4288 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4289 | ret = __perf_read_group_add(child, read_format, values); | |
4290 | if (ret) | |
4291 | goto unlock; | |
4292 | } | |
abf4868b | 4293 | |
fa8c2693 | 4294 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4295 | |
7d88962e | 4296 | ret = event->read_size; |
fa8c2693 PZ |
4297 | if (copy_to_user(buf, values, event->read_size)) |
4298 | ret = -EFAULT; | |
7d88962e | 4299 | goto out; |
fa8c2693 | 4300 | |
7d88962e SB |
4301 | unlock: |
4302 | mutex_unlock(&leader->child_mutex); | |
4303 | out: | |
fa8c2693 | 4304 | kfree(values); |
abf4868b | 4305 | return ret; |
3dab77fb PZ |
4306 | } |
4307 | ||
b15f495b | 4308 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4309 | u64 read_format, char __user *buf) |
4310 | { | |
59ed446f | 4311 | u64 enabled, running; |
3dab77fb PZ |
4312 | u64 values[4]; |
4313 | int n = 0; | |
4314 | ||
59ed446f PZ |
4315 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4316 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4317 | values[n++] = enabled; | |
4318 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4319 | values[n++] = running; | |
3dab77fb | 4320 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4321 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4322 | |
4323 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4324 | return -EFAULT; | |
4325 | ||
4326 | return n * sizeof(u64); | |
4327 | } | |
4328 | ||
dc633982 JO |
4329 | static bool is_event_hup(struct perf_event *event) |
4330 | { | |
4331 | bool no_children; | |
4332 | ||
a69b0ca4 | 4333 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4334 | return false; |
4335 | ||
4336 | mutex_lock(&event->child_mutex); | |
4337 | no_children = list_empty(&event->child_list); | |
4338 | mutex_unlock(&event->child_mutex); | |
4339 | return no_children; | |
4340 | } | |
4341 | ||
0793a61d | 4342 | /* |
cdd6c482 | 4343 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4344 | */ |
4345 | static ssize_t | |
b15f495b | 4346 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4347 | { |
cdd6c482 | 4348 | u64 read_format = event->attr.read_format; |
3dab77fb | 4349 | int ret; |
0793a61d | 4350 | |
3b6f9e5c | 4351 | /* |
cdd6c482 | 4352 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4353 | * error state (i.e. because it was pinned but it couldn't be |
4354 | * scheduled on to the CPU at some point). | |
4355 | */ | |
cdd6c482 | 4356 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4357 | return 0; |
4358 | ||
c320c7b7 | 4359 | if (count < event->read_size) |
3dab77fb PZ |
4360 | return -ENOSPC; |
4361 | ||
cdd6c482 | 4362 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4363 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4364 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4365 | else |
b15f495b | 4366 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4367 | |
3dab77fb | 4368 | return ret; |
0793a61d TG |
4369 | } |
4370 | ||
0793a61d TG |
4371 | static ssize_t |
4372 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4373 | { | |
cdd6c482 | 4374 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4375 | struct perf_event_context *ctx; |
4376 | int ret; | |
0793a61d | 4377 | |
f63a8daa | 4378 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4379 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4380 | perf_event_ctx_unlock(event, ctx); |
4381 | ||
4382 | return ret; | |
0793a61d TG |
4383 | } |
4384 | ||
4385 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4386 | { | |
cdd6c482 | 4387 | struct perf_event *event = file->private_data; |
76369139 | 4388 | struct ring_buffer *rb; |
61b67684 | 4389 | unsigned int events = POLLHUP; |
c7138f37 | 4390 | |
e708d7ad | 4391 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4392 | |
dc633982 | 4393 | if (is_event_hup(event)) |
179033b3 | 4394 | return events; |
c7138f37 | 4395 | |
10c6db11 | 4396 | /* |
9bb5d40c PZ |
4397 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4398 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4399 | */ |
4400 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4401 | rb = event->rb; |
4402 | if (rb) | |
76369139 | 4403 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4404 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4405 | return events; |
4406 | } | |
4407 | ||
f63a8daa | 4408 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4409 | { |
7d88962e | 4410 | (void)perf_event_read(event, false); |
e7850595 | 4411 | local64_set(&event->count, 0); |
cdd6c482 | 4412 | perf_event_update_userpage(event); |
3df5edad PZ |
4413 | } |
4414 | ||
c93f7669 | 4415 | /* |
cdd6c482 IM |
4416 | * Holding the top-level event's child_mutex means that any |
4417 | * descendant process that has inherited this event will block | |
8ba289b8 | 4418 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4419 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4420 | */ |
cdd6c482 IM |
4421 | static void perf_event_for_each_child(struct perf_event *event, |
4422 | void (*func)(struct perf_event *)) | |
3df5edad | 4423 | { |
cdd6c482 | 4424 | struct perf_event *child; |
3df5edad | 4425 | |
cdd6c482 | 4426 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4427 | |
cdd6c482 IM |
4428 | mutex_lock(&event->child_mutex); |
4429 | func(event); | |
4430 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4431 | func(child); |
cdd6c482 | 4432 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4433 | } |
4434 | ||
cdd6c482 IM |
4435 | static void perf_event_for_each(struct perf_event *event, |
4436 | void (*func)(struct perf_event *)) | |
3df5edad | 4437 | { |
cdd6c482 IM |
4438 | struct perf_event_context *ctx = event->ctx; |
4439 | struct perf_event *sibling; | |
3df5edad | 4440 | |
f63a8daa PZ |
4441 | lockdep_assert_held(&ctx->mutex); |
4442 | ||
cdd6c482 | 4443 | event = event->group_leader; |
75f937f2 | 4444 | |
cdd6c482 | 4445 | perf_event_for_each_child(event, func); |
cdd6c482 | 4446 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4447 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4448 | } |
4449 | ||
fae3fde6 PZ |
4450 | static void __perf_event_period(struct perf_event *event, |
4451 | struct perf_cpu_context *cpuctx, | |
4452 | struct perf_event_context *ctx, | |
4453 | void *info) | |
c7999c6f | 4454 | { |
fae3fde6 | 4455 | u64 value = *((u64 *)info); |
c7999c6f | 4456 | bool active; |
08247e31 | 4457 | |
cdd6c482 | 4458 | if (event->attr.freq) { |
cdd6c482 | 4459 | event->attr.sample_freq = value; |
08247e31 | 4460 | } else { |
cdd6c482 IM |
4461 | event->attr.sample_period = value; |
4462 | event->hw.sample_period = value; | |
08247e31 | 4463 | } |
bad7192b PZ |
4464 | |
4465 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4466 | if (active) { | |
4467 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4468 | /* |
4469 | * We could be throttled; unthrottle now to avoid the tick | |
4470 | * trying to unthrottle while we already re-started the event. | |
4471 | */ | |
4472 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4473 | event->hw.interrupts = 0; | |
4474 | perf_log_throttle(event, 1); | |
4475 | } | |
bad7192b PZ |
4476 | event->pmu->stop(event, PERF_EF_UPDATE); |
4477 | } | |
4478 | ||
4479 | local64_set(&event->hw.period_left, 0); | |
4480 | ||
4481 | if (active) { | |
4482 | event->pmu->start(event, PERF_EF_RELOAD); | |
4483 | perf_pmu_enable(ctx->pmu); | |
4484 | } | |
c7999c6f PZ |
4485 | } |
4486 | ||
4487 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4488 | { | |
c7999c6f PZ |
4489 | u64 value; |
4490 | ||
4491 | if (!is_sampling_event(event)) | |
4492 | return -EINVAL; | |
4493 | ||
4494 | if (copy_from_user(&value, arg, sizeof(value))) | |
4495 | return -EFAULT; | |
4496 | ||
4497 | if (!value) | |
4498 | return -EINVAL; | |
4499 | ||
4500 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4501 | return -EINVAL; | |
4502 | ||
fae3fde6 | 4503 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4504 | |
c7999c6f | 4505 | return 0; |
08247e31 PZ |
4506 | } |
4507 | ||
ac9721f3 PZ |
4508 | static const struct file_operations perf_fops; |
4509 | ||
2903ff01 | 4510 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4511 | { |
2903ff01 AV |
4512 | struct fd f = fdget(fd); |
4513 | if (!f.file) | |
4514 | return -EBADF; | |
ac9721f3 | 4515 | |
2903ff01 AV |
4516 | if (f.file->f_op != &perf_fops) { |
4517 | fdput(f); | |
4518 | return -EBADF; | |
ac9721f3 | 4519 | } |
2903ff01 AV |
4520 | *p = f; |
4521 | return 0; | |
ac9721f3 PZ |
4522 | } |
4523 | ||
4524 | static int perf_event_set_output(struct perf_event *event, | |
4525 | struct perf_event *output_event); | |
6fb2915d | 4526 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4527 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4528 | |
f63a8daa | 4529 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4530 | { |
cdd6c482 | 4531 | void (*func)(struct perf_event *); |
3df5edad | 4532 | u32 flags = arg; |
d859e29f PM |
4533 | |
4534 | switch (cmd) { | |
cdd6c482 | 4535 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4536 | func = _perf_event_enable; |
d859e29f | 4537 | break; |
cdd6c482 | 4538 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4539 | func = _perf_event_disable; |
79f14641 | 4540 | break; |
cdd6c482 | 4541 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4542 | func = _perf_event_reset; |
6de6a7b9 | 4543 | break; |
3df5edad | 4544 | |
cdd6c482 | 4545 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4546 | return _perf_event_refresh(event, arg); |
08247e31 | 4547 | |
cdd6c482 IM |
4548 | case PERF_EVENT_IOC_PERIOD: |
4549 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4550 | |
cf4957f1 JO |
4551 | case PERF_EVENT_IOC_ID: |
4552 | { | |
4553 | u64 id = primary_event_id(event); | |
4554 | ||
4555 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4556 | return -EFAULT; | |
4557 | return 0; | |
4558 | } | |
4559 | ||
cdd6c482 | 4560 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4561 | { |
ac9721f3 | 4562 | int ret; |
ac9721f3 | 4563 | if (arg != -1) { |
2903ff01 AV |
4564 | struct perf_event *output_event; |
4565 | struct fd output; | |
4566 | ret = perf_fget_light(arg, &output); | |
4567 | if (ret) | |
4568 | return ret; | |
4569 | output_event = output.file->private_data; | |
4570 | ret = perf_event_set_output(event, output_event); | |
4571 | fdput(output); | |
4572 | } else { | |
4573 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4574 | } |
ac9721f3 PZ |
4575 | return ret; |
4576 | } | |
a4be7c27 | 4577 | |
6fb2915d LZ |
4578 | case PERF_EVENT_IOC_SET_FILTER: |
4579 | return perf_event_set_filter(event, (void __user *)arg); | |
4580 | ||
2541517c AS |
4581 | case PERF_EVENT_IOC_SET_BPF: |
4582 | return perf_event_set_bpf_prog(event, arg); | |
4583 | ||
86e7972f WN |
4584 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4585 | struct ring_buffer *rb; | |
4586 | ||
4587 | rcu_read_lock(); | |
4588 | rb = rcu_dereference(event->rb); | |
4589 | if (!rb || !rb->nr_pages) { | |
4590 | rcu_read_unlock(); | |
4591 | return -EINVAL; | |
4592 | } | |
4593 | rb_toggle_paused(rb, !!arg); | |
4594 | rcu_read_unlock(); | |
4595 | return 0; | |
4596 | } | |
d859e29f | 4597 | default: |
3df5edad | 4598 | return -ENOTTY; |
d859e29f | 4599 | } |
3df5edad PZ |
4600 | |
4601 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4602 | perf_event_for_each(event, func); |
3df5edad | 4603 | else |
cdd6c482 | 4604 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4605 | |
4606 | return 0; | |
d859e29f PM |
4607 | } |
4608 | ||
f63a8daa PZ |
4609 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4610 | { | |
4611 | struct perf_event *event = file->private_data; | |
4612 | struct perf_event_context *ctx; | |
4613 | long ret; | |
4614 | ||
4615 | ctx = perf_event_ctx_lock(event); | |
4616 | ret = _perf_ioctl(event, cmd, arg); | |
4617 | perf_event_ctx_unlock(event, ctx); | |
4618 | ||
4619 | return ret; | |
4620 | } | |
4621 | ||
b3f20785 PM |
4622 | #ifdef CONFIG_COMPAT |
4623 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4624 | unsigned long arg) | |
4625 | { | |
4626 | switch (_IOC_NR(cmd)) { | |
4627 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4628 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4629 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4630 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4631 | cmd &= ~IOCSIZE_MASK; | |
4632 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4633 | } | |
4634 | break; | |
4635 | } | |
4636 | return perf_ioctl(file, cmd, arg); | |
4637 | } | |
4638 | #else | |
4639 | # define perf_compat_ioctl NULL | |
4640 | #endif | |
4641 | ||
cdd6c482 | 4642 | int perf_event_task_enable(void) |
771d7cde | 4643 | { |
f63a8daa | 4644 | struct perf_event_context *ctx; |
cdd6c482 | 4645 | struct perf_event *event; |
771d7cde | 4646 | |
cdd6c482 | 4647 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4648 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4649 | ctx = perf_event_ctx_lock(event); | |
4650 | perf_event_for_each_child(event, _perf_event_enable); | |
4651 | perf_event_ctx_unlock(event, ctx); | |
4652 | } | |
cdd6c482 | 4653 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4654 | |
4655 | return 0; | |
4656 | } | |
4657 | ||
cdd6c482 | 4658 | int perf_event_task_disable(void) |
771d7cde | 4659 | { |
f63a8daa | 4660 | struct perf_event_context *ctx; |
cdd6c482 | 4661 | struct perf_event *event; |
771d7cde | 4662 | |
cdd6c482 | 4663 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4664 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4665 | ctx = perf_event_ctx_lock(event); | |
4666 | perf_event_for_each_child(event, _perf_event_disable); | |
4667 | perf_event_ctx_unlock(event, ctx); | |
4668 | } | |
cdd6c482 | 4669 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4670 | |
4671 | return 0; | |
4672 | } | |
4673 | ||
cdd6c482 | 4674 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4675 | { |
a4eaf7f1 PZ |
4676 | if (event->hw.state & PERF_HES_STOPPED) |
4677 | return 0; | |
4678 | ||
cdd6c482 | 4679 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4680 | return 0; |
4681 | ||
35edc2a5 | 4682 | return event->pmu->event_idx(event); |
194002b2 PZ |
4683 | } |
4684 | ||
c4794295 | 4685 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4686 | u64 *now, |
7f310a5d EM |
4687 | u64 *enabled, |
4688 | u64 *running) | |
c4794295 | 4689 | { |
e3f3541c | 4690 | u64 ctx_time; |
c4794295 | 4691 | |
e3f3541c PZ |
4692 | *now = perf_clock(); |
4693 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4694 | *enabled = ctx_time - event->tstamp_enabled; |
4695 | *running = ctx_time - event->tstamp_running; | |
4696 | } | |
4697 | ||
fa731587 PZ |
4698 | static void perf_event_init_userpage(struct perf_event *event) |
4699 | { | |
4700 | struct perf_event_mmap_page *userpg; | |
4701 | struct ring_buffer *rb; | |
4702 | ||
4703 | rcu_read_lock(); | |
4704 | rb = rcu_dereference(event->rb); | |
4705 | if (!rb) | |
4706 | goto unlock; | |
4707 | ||
4708 | userpg = rb->user_page; | |
4709 | ||
4710 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4711 | userpg->cap_bit0_is_deprecated = 1; | |
4712 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4713 | userpg->data_offset = PAGE_SIZE; |
4714 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4715 | |
4716 | unlock: | |
4717 | rcu_read_unlock(); | |
4718 | } | |
4719 | ||
c1317ec2 AL |
4720 | void __weak arch_perf_update_userpage( |
4721 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4722 | { |
4723 | } | |
4724 | ||
38ff667b PZ |
4725 | /* |
4726 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4727 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4728 | * code calls this from NMI context. | |
4729 | */ | |
cdd6c482 | 4730 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4731 | { |
cdd6c482 | 4732 | struct perf_event_mmap_page *userpg; |
76369139 | 4733 | struct ring_buffer *rb; |
e3f3541c | 4734 | u64 enabled, running, now; |
38ff667b PZ |
4735 | |
4736 | rcu_read_lock(); | |
5ec4c599 PZ |
4737 | rb = rcu_dereference(event->rb); |
4738 | if (!rb) | |
4739 | goto unlock; | |
4740 | ||
0d641208 EM |
4741 | /* |
4742 | * compute total_time_enabled, total_time_running | |
4743 | * based on snapshot values taken when the event | |
4744 | * was last scheduled in. | |
4745 | * | |
4746 | * we cannot simply called update_context_time() | |
4747 | * because of locking issue as we can be called in | |
4748 | * NMI context | |
4749 | */ | |
e3f3541c | 4750 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4751 | |
76369139 | 4752 | userpg = rb->user_page; |
7b732a75 PZ |
4753 | /* |
4754 | * Disable preemption so as to not let the corresponding user-space | |
4755 | * spin too long if we get preempted. | |
4756 | */ | |
4757 | preempt_disable(); | |
37d81828 | 4758 | ++userpg->lock; |
92f22a38 | 4759 | barrier(); |
cdd6c482 | 4760 | userpg->index = perf_event_index(event); |
b5e58793 | 4761 | userpg->offset = perf_event_count(event); |
365a4038 | 4762 | if (userpg->index) |
e7850595 | 4763 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4764 | |
0d641208 | 4765 | userpg->time_enabled = enabled + |
cdd6c482 | 4766 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4767 | |
0d641208 | 4768 | userpg->time_running = running + |
cdd6c482 | 4769 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4770 | |
c1317ec2 | 4771 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4772 | |
92f22a38 | 4773 | barrier(); |
37d81828 | 4774 | ++userpg->lock; |
7b732a75 | 4775 | preempt_enable(); |
38ff667b | 4776 | unlock: |
7b732a75 | 4777 | rcu_read_unlock(); |
37d81828 PM |
4778 | } |
4779 | ||
906010b2 PZ |
4780 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4781 | { | |
4782 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4783 | struct ring_buffer *rb; |
906010b2 PZ |
4784 | int ret = VM_FAULT_SIGBUS; |
4785 | ||
4786 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4787 | if (vmf->pgoff == 0) | |
4788 | ret = 0; | |
4789 | return ret; | |
4790 | } | |
4791 | ||
4792 | rcu_read_lock(); | |
76369139 FW |
4793 | rb = rcu_dereference(event->rb); |
4794 | if (!rb) | |
906010b2 PZ |
4795 | goto unlock; |
4796 | ||
4797 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4798 | goto unlock; | |
4799 | ||
76369139 | 4800 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4801 | if (!vmf->page) |
4802 | goto unlock; | |
4803 | ||
4804 | get_page(vmf->page); | |
4805 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4806 | vmf->page->index = vmf->pgoff; | |
4807 | ||
4808 | ret = 0; | |
4809 | unlock: | |
4810 | rcu_read_unlock(); | |
4811 | ||
4812 | return ret; | |
4813 | } | |
4814 | ||
10c6db11 PZ |
4815 | static void ring_buffer_attach(struct perf_event *event, |
4816 | struct ring_buffer *rb) | |
4817 | { | |
b69cf536 | 4818 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4819 | unsigned long flags; |
4820 | ||
b69cf536 PZ |
4821 | if (event->rb) { |
4822 | /* | |
4823 | * Should be impossible, we set this when removing | |
4824 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4825 | */ | |
4826 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4827 | |
b69cf536 | 4828 | old_rb = event->rb; |
b69cf536 PZ |
4829 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4830 | list_del_rcu(&event->rb_entry); | |
4831 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4832 | |
2f993cf0 ON |
4833 | event->rcu_batches = get_state_synchronize_rcu(); |
4834 | event->rcu_pending = 1; | |
b69cf536 | 4835 | } |
10c6db11 | 4836 | |
b69cf536 | 4837 | if (rb) { |
2f993cf0 ON |
4838 | if (event->rcu_pending) { |
4839 | cond_synchronize_rcu(event->rcu_batches); | |
4840 | event->rcu_pending = 0; | |
4841 | } | |
4842 | ||
b69cf536 PZ |
4843 | spin_lock_irqsave(&rb->event_lock, flags); |
4844 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4845 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4846 | } | |
4847 | ||
4848 | rcu_assign_pointer(event->rb, rb); | |
4849 | ||
4850 | if (old_rb) { | |
4851 | ring_buffer_put(old_rb); | |
4852 | /* | |
4853 | * Since we detached before setting the new rb, so that we | |
4854 | * could attach the new rb, we could have missed a wakeup. | |
4855 | * Provide it now. | |
4856 | */ | |
4857 | wake_up_all(&event->waitq); | |
4858 | } | |
10c6db11 PZ |
4859 | } |
4860 | ||
4861 | static void ring_buffer_wakeup(struct perf_event *event) | |
4862 | { | |
4863 | struct ring_buffer *rb; | |
4864 | ||
4865 | rcu_read_lock(); | |
4866 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4867 | if (rb) { |
4868 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4869 | wake_up_all(&event->waitq); | |
4870 | } | |
10c6db11 PZ |
4871 | rcu_read_unlock(); |
4872 | } | |
4873 | ||
fdc26706 | 4874 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4875 | { |
76369139 | 4876 | struct ring_buffer *rb; |
7b732a75 | 4877 | |
ac9721f3 | 4878 | rcu_read_lock(); |
76369139 FW |
4879 | rb = rcu_dereference(event->rb); |
4880 | if (rb) { | |
4881 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4882 | rb = NULL; | |
ac9721f3 PZ |
4883 | } |
4884 | rcu_read_unlock(); | |
4885 | ||
76369139 | 4886 | return rb; |
ac9721f3 PZ |
4887 | } |
4888 | ||
fdc26706 | 4889 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4890 | { |
76369139 | 4891 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4892 | return; |
7b732a75 | 4893 | |
9bb5d40c | 4894 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 4895 | |
76369139 | 4896 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
4897 | } |
4898 | ||
4899 | static void perf_mmap_open(struct vm_area_struct *vma) | |
4900 | { | |
cdd6c482 | 4901 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4902 | |
cdd6c482 | 4903 | atomic_inc(&event->mmap_count); |
9bb5d40c | 4904 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 4905 | |
45bfb2e5 PZ |
4906 | if (vma->vm_pgoff) |
4907 | atomic_inc(&event->rb->aux_mmap_count); | |
4908 | ||
1e0fb9ec AL |
4909 | if (event->pmu->event_mapped) |
4910 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
4911 | } |
4912 | ||
95ff4ca2 AS |
4913 | static void perf_pmu_output_stop(struct perf_event *event); |
4914 | ||
9bb5d40c PZ |
4915 | /* |
4916 | * A buffer can be mmap()ed multiple times; either directly through the same | |
4917 | * event, or through other events by use of perf_event_set_output(). | |
4918 | * | |
4919 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
4920 | * the buffer here, where we still have a VM context. This means we need | |
4921 | * to detach all events redirecting to us. | |
4922 | */ | |
7b732a75 PZ |
4923 | static void perf_mmap_close(struct vm_area_struct *vma) |
4924 | { | |
cdd6c482 | 4925 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4926 | |
b69cf536 | 4927 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
4928 | struct user_struct *mmap_user = rb->mmap_user; |
4929 | int mmap_locked = rb->mmap_locked; | |
4930 | unsigned long size = perf_data_size(rb); | |
789f90fc | 4931 | |
1e0fb9ec AL |
4932 | if (event->pmu->event_unmapped) |
4933 | event->pmu->event_unmapped(event); | |
4934 | ||
45bfb2e5 PZ |
4935 | /* |
4936 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
4937 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
4938 | * serialize with perf_mmap here. | |
4939 | */ | |
4940 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
4941 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
4942 | /* |
4943 | * Stop all AUX events that are writing to this buffer, | |
4944 | * so that we can free its AUX pages and corresponding PMU | |
4945 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
4946 | * they won't start any more (see perf_aux_output_begin()). | |
4947 | */ | |
4948 | perf_pmu_output_stop(event); | |
4949 | ||
4950 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
4951 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
4952 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
4953 | ||
95ff4ca2 | 4954 | /* this has to be the last one */ |
45bfb2e5 | 4955 | rb_free_aux(rb); |
95ff4ca2 AS |
4956 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
4957 | ||
45bfb2e5 PZ |
4958 | mutex_unlock(&event->mmap_mutex); |
4959 | } | |
4960 | ||
9bb5d40c PZ |
4961 | atomic_dec(&rb->mmap_count); |
4962 | ||
4963 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 4964 | goto out_put; |
9bb5d40c | 4965 | |
b69cf536 | 4966 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
4967 | mutex_unlock(&event->mmap_mutex); |
4968 | ||
4969 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
4970 | if (atomic_read(&rb->mmap_count)) |
4971 | goto out_put; | |
ac9721f3 | 4972 | |
9bb5d40c PZ |
4973 | /* |
4974 | * No other mmap()s, detach from all other events that might redirect | |
4975 | * into the now unreachable buffer. Somewhat complicated by the | |
4976 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
4977 | */ | |
4978 | again: | |
4979 | rcu_read_lock(); | |
4980 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
4981 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
4982 | /* | |
4983 | * This event is en-route to free_event() which will | |
4984 | * detach it and remove it from the list. | |
4985 | */ | |
4986 | continue; | |
4987 | } | |
4988 | rcu_read_unlock(); | |
789f90fc | 4989 | |
9bb5d40c PZ |
4990 | mutex_lock(&event->mmap_mutex); |
4991 | /* | |
4992 | * Check we didn't race with perf_event_set_output() which can | |
4993 | * swizzle the rb from under us while we were waiting to | |
4994 | * acquire mmap_mutex. | |
4995 | * | |
4996 | * If we find a different rb; ignore this event, a next | |
4997 | * iteration will no longer find it on the list. We have to | |
4998 | * still restart the iteration to make sure we're not now | |
4999 | * iterating the wrong list. | |
5000 | */ | |
b69cf536 PZ |
5001 | if (event->rb == rb) |
5002 | ring_buffer_attach(event, NULL); | |
5003 | ||
cdd6c482 | 5004 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5005 | put_event(event); |
ac9721f3 | 5006 | |
9bb5d40c PZ |
5007 | /* |
5008 | * Restart the iteration; either we're on the wrong list or | |
5009 | * destroyed its integrity by doing a deletion. | |
5010 | */ | |
5011 | goto again; | |
7b732a75 | 5012 | } |
9bb5d40c PZ |
5013 | rcu_read_unlock(); |
5014 | ||
5015 | /* | |
5016 | * It could be there's still a few 0-ref events on the list; they'll | |
5017 | * get cleaned up by free_event() -- they'll also still have their | |
5018 | * ref on the rb and will free it whenever they are done with it. | |
5019 | * | |
5020 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5021 | * undo the VM accounting. | |
5022 | */ | |
5023 | ||
5024 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5025 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5026 | free_uid(mmap_user); | |
5027 | ||
b69cf536 | 5028 | out_put: |
9bb5d40c | 5029 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5030 | } |
5031 | ||
f0f37e2f | 5032 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5033 | .open = perf_mmap_open, |
45bfb2e5 | 5034 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5035 | .fault = perf_mmap_fault, |
5036 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5037 | }; |
5038 | ||
5039 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5040 | { | |
cdd6c482 | 5041 | struct perf_event *event = file->private_data; |
22a4f650 | 5042 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5043 | struct user_struct *user = current_user(); |
22a4f650 | 5044 | unsigned long locked, lock_limit; |
45bfb2e5 | 5045 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5046 | unsigned long vma_size; |
5047 | unsigned long nr_pages; | |
45bfb2e5 | 5048 | long user_extra = 0, extra = 0; |
d57e34fd | 5049 | int ret = 0, flags = 0; |
37d81828 | 5050 | |
c7920614 PZ |
5051 | /* |
5052 | * Don't allow mmap() of inherited per-task counters. This would | |
5053 | * create a performance issue due to all children writing to the | |
76369139 | 5054 | * same rb. |
c7920614 PZ |
5055 | */ |
5056 | if (event->cpu == -1 && event->attr.inherit) | |
5057 | return -EINVAL; | |
5058 | ||
43a21ea8 | 5059 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5060 | return -EINVAL; |
7b732a75 PZ |
5061 | |
5062 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5063 | |
5064 | if (vma->vm_pgoff == 0) { | |
5065 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5066 | } else { | |
5067 | /* | |
5068 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5069 | * mapped, all subsequent mappings should have the same size | |
5070 | * and offset. Must be above the normal perf buffer. | |
5071 | */ | |
5072 | u64 aux_offset, aux_size; | |
5073 | ||
5074 | if (!event->rb) | |
5075 | return -EINVAL; | |
5076 | ||
5077 | nr_pages = vma_size / PAGE_SIZE; | |
5078 | ||
5079 | mutex_lock(&event->mmap_mutex); | |
5080 | ret = -EINVAL; | |
5081 | ||
5082 | rb = event->rb; | |
5083 | if (!rb) | |
5084 | goto aux_unlock; | |
5085 | ||
5086 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5087 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5088 | ||
5089 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5090 | goto aux_unlock; | |
5091 | ||
5092 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5093 | goto aux_unlock; | |
5094 | ||
5095 | /* already mapped with a different offset */ | |
5096 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5097 | goto aux_unlock; | |
5098 | ||
5099 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5100 | goto aux_unlock; | |
5101 | ||
5102 | /* already mapped with a different size */ | |
5103 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5104 | goto aux_unlock; | |
5105 | ||
5106 | if (!is_power_of_2(nr_pages)) | |
5107 | goto aux_unlock; | |
5108 | ||
5109 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5110 | goto aux_unlock; | |
5111 | ||
5112 | if (rb_has_aux(rb)) { | |
5113 | atomic_inc(&rb->aux_mmap_count); | |
5114 | ret = 0; | |
5115 | goto unlock; | |
5116 | } | |
5117 | ||
5118 | atomic_set(&rb->aux_mmap_count, 1); | |
5119 | user_extra = nr_pages; | |
5120 | ||
5121 | goto accounting; | |
5122 | } | |
7b732a75 | 5123 | |
7730d865 | 5124 | /* |
76369139 | 5125 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5126 | * can do bitmasks instead of modulo. |
5127 | */ | |
2ed11312 | 5128 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5129 | return -EINVAL; |
5130 | ||
7b732a75 | 5131 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5132 | return -EINVAL; |
5133 | ||
cdd6c482 | 5134 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5135 | again: |
cdd6c482 | 5136 | mutex_lock(&event->mmap_mutex); |
76369139 | 5137 | if (event->rb) { |
9bb5d40c | 5138 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5139 | ret = -EINVAL; |
9bb5d40c PZ |
5140 | goto unlock; |
5141 | } | |
5142 | ||
5143 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5144 | /* | |
5145 | * Raced against perf_mmap_close() through | |
5146 | * perf_event_set_output(). Try again, hope for better | |
5147 | * luck. | |
5148 | */ | |
5149 | mutex_unlock(&event->mmap_mutex); | |
5150 | goto again; | |
5151 | } | |
5152 | ||
ebb3c4c4 PZ |
5153 | goto unlock; |
5154 | } | |
5155 | ||
789f90fc | 5156 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5157 | |
5158 | accounting: | |
cdd6c482 | 5159 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5160 | |
5161 | /* | |
5162 | * Increase the limit linearly with more CPUs: | |
5163 | */ | |
5164 | user_lock_limit *= num_online_cpus(); | |
5165 | ||
789f90fc | 5166 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5167 | |
789f90fc PZ |
5168 | if (user_locked > user_lock_limit) |
5169 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5170 | |
78d7d407 | 5171 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5172 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5173 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5174 | |
459ec28a IM |
5175 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5176 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5177 | ret = -EPERM; |
5178 | goto unlock; | |
5179 | } | |
7b732a75 | 5180 | |
45bfb2e5 | 5181 | WARN_ON(!rb && event->rb); |
906010b2 | 5182 | |
d57e34fd | 5183 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5184 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5185 | |
76369139 | 5186 | if (!rb) { |
45bfb2e5 PZ |
5187 | rb = rb_alloc(nr_pages, |
5188 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5189 | event->cpu, flags); | |
26cb63ad | 5190 | |
45bfb2e5 PZ |
5191 | if (!rb) { |
5192 | ret = -ENOMEM; | |
5193 | goto unlock; | |
5194 | } | |
43a21ea8 | 5195 | |
45bfb2e5 PZ |
5196 | atomic_set(&rb->mmap_count, 1); |
5197 | rb->mmap_user = get_current_user(); | |
5198 | rb->mmap_locked = extra; | |
26cb63ad | 5199 | |
45bfb2e5 | 5200 | ring_buffer_attach(event, rb); |
ac9721f3 | 5201 | |
45bfb2e5 PZ |
5202 | perf_event_init_userpage(event); |
5203 | perf_event_update_userpage(event); | |
5204 | } else { | |
1a594131 AS |
5205 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5206 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5207 | if (!ret) |
5208 | rb->aux_mmap_locked = extra; | |
5209 | } | |
9a0f05cb | 5210 | |
ebb3c4c4 | 5211 | unlock: |
45bfb2e5 PZ |
5212 | if (!ret) { |
5213 | atomic_long_add(user_extra, &user->locked_vm); | |
5214 | vma->vm_mm->pinned_vm += extra; | |
5215 | ||
ac9721f3 | 5216 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5217 | } else if (rb) { |
5218 | atomic_dec(&rb->mmap_count); | |
5219 | } | |
5220 | aux_unlock: | |
cdd6c482 | 5221 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5222 | |
9bb5d40c PZ |
5223 | /* |
5224 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5225 | * vma. | |
5226 | */ | |
26cb63ad | 5227 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5228 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5229 | |
1e0fb9ec AL |
5230 | if (event->pmu->event_mapped) |
5231 | event->pmu->event_mapped(event); | |
5232 | ||
7b732a75 | 5233 | return ret; |
37d81828 PM |
5234 | } |
5235 | ||
3c446b3d PZ |
5236 | static int perf_fasync(int fd, struct file *filp, int on) |
5237 | { | |
496ad9aa | 5238 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5239 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5240 | int retval; |
5241 | ||
5955102c | 5242 | inode_lock(inode); |
cdd6c482 | 5243 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5244 | inode_unlock(inode); |
3c446b3d PZ |
5245 | |
5246 | if (retval < 0) | |
5247 | return retval; | |
5248 | ||
5249 | return 0; | |
5250 | } | |
5251 | ||
0793a61d | 5252 | static const struct file_operations perf_fops = { |
3326c1ce | 5253 | .llseek = no_llseek, |
0793a61d TG |
5254 | .release = perf_release, |
5255 | .read = perf_read, | |
5256 | .poll = perf_poll, | |
d859e29f | 5257 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5258 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5259 | .mmap = perf_mmap, |
3c446b3d | 5260 | .fasync = perf_fasync, |
0793a61d TG |
5261 | }; |
5262 | ||
925d519a | 5263 | /* |
cdd6c482 | 5264 | * Perf event wakeup |
925d519a PZ |
5265 | * |
5266 | * If there's data, ensure we set the poll() state and publish everything | |
5267 | * to user-space before waking everybody up. | |
5268 | */ | |
5269 | ||
fed66e2c PZ |
5270 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5271 | { | |
5272 | /* only the parent has fasync state */ | |
5273 | if (event->parent) | |
5274 | event = event->parent; | |
5275 | return &event->fasync; | |
5276 | } | |
5277 | ||
cdd6c482 | 5278 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5279 | { |
10c6db11 | 5280 | ring_buffer_wakeup(event); |
4c9e2542 | 5281 | |
cdd6c482 | 5282 | if (event->pending_kill) { |
fed66e2c | 5283 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5284 | event->pending_kill = 0; |
4c9e2542 | 5285 | } |
925d519a PZ |
5286 | } |
5287 | ||
e360adbe | 5288 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5289 | { |
cdd6c482 IM |
5290 | struct perf_event *event = container_of(entry, |
5291 | struct perf_event, pending); | |
d525211f PZ |
5292 | int rctx; |
5293 | ||
5294 | rctx = perf_swevent_get_recursion_context(); | |
5295 | /* | |
5296 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5297 | * and we won't recurse 'further'. | |
5298 | */ | |
79f14641 | 5299 | |
cdd6c482 IM |
5300 | if (event->pending_disable) { |
5301 | event->pending_disable = 0; | |
fae3fde6 | 5302 | perf_event_disable_local(event); |
79f14641 PZ |
5303 | } |
5304 | ||
cdd6c482 IM |
5305 | if (event->pending_wakeup) { |
5306 | event->pending_wakeup = 0; | |
5307 | perf_event_wakeup(event); | |
79f14641 | 5308 | } |
d525211f PZ |
5309 | |
5310 | if (rctx >= 0) | |
5311 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5312 | } |
5313 | ||
39447b38 ZY |
5314 | /* |
5315 | * We assume there is only KVM supporting the callbacks. | |
5316 | * Later on, we might change it to a list if there is | |
5317 | * another virtualization implementation supporting the callbacks. | |
5318 | */ | |
5319 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5320 | ||
5321 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5322 | { | |
5323 | perf_guest_cbs = cbs; | |
5324 | return 0; | |
5325 | } | |
5326 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5327 | ||
5328 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5329 | { | |
5330 | perf_guest_cbs = NULL; | |
5331 | return 0; | |
5332 | } | |
5333 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5334 | ||
4018994f JO |
5335 | static void |
5336 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5337 | struct pt_regs *regs, u64 mask) | |
5338 | { | |
5339 | int bit; | |
29dd3288 | 5340 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5341 | |
29dd3288 MS |
5342 | bitmap_from_u64(_mask, mask); |
5343 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5344 | u64 val; |
5345 | ||
5346 | val = perf_reg_value(regs, bit); | |
5347 | perf_output_put(handle, val); | |
5348 | } | |
5349 | } | |
5350 | ||
60e2364e | 5351 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5352 | struct pt_regs *regs, |
5353 | struct pt_regs *regs_user_copy) | |
4018994f | 5354 | { |
88a7c26a AL |
5355 | if (user_mode(regs)) { |
5356 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5357 | regs_user->regs = regs; |
88a7c26a AL |
5358 | } else if (current->mm) { |
5359 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5360 | } else { |
5361 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5362 | regs_user->regs = NULL; | |
4018994f JO |
5363 | } |
5364 | } | |
5365 | ||
60e2364e SE |
5366 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5367 | struct pt_regs *regs) | |
5368 | { | |
5369 | regs_intr->regs = regs; | |
5370 | regs_intr->abi = perf_reg_abi(current); | |
5371 | } | |
5372 | ||
5373 | ||
c5ebcedb JO |
5374 | /* |
5375 | * Get remaining task size from user stack pointer. | |
5376 | * | |
5377 | * It'd be better to take stack vma map and limit this more | |
5378 | * precisly, but there's no way to get it safely under interrupt, | |
5379 | * so using TASK_SIZE as limit. | |
5380 | */ | |
5381 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5382 | { | |
5383 | unsigned long addr = perf_user_stack_pointer(regs); | |
5384 | ||
5385 | if (!addr || addr >= TASK_SIZE) | |
5386 | return 0; | |
5387 | ||
5388 | return TASK_SIZE - addr; | |
5389 | } | |
5390 | ||
5391 | static u16 | |
5392 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5393 | struct pt_regs *regs) | |
5394 | { | |
5395 | u64 task_size; | |
5396 | ||
5397 | /* No regs, no stack pointer, no dump. */ | |
5398 | if (!regs) | |
5399 | return 0; | |
5400 | ||
5401 | /* | |
5402 | * Check if we fit in with the requested stack size into the: | |
5403 | * - TASK_SIZE | |
5404 | * If we don't, we limit the size to the TASK_SIZE. | |
5405 | * | |
5406 | * - remaining sample size | |
5407 | * If we don't, we customize the stack size to | |
5408 | * fit in to the remaining sample size. | |
5409 | */ | |
5410 | ||
5411 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5412 | stack_size = min(stack_size, (u16) task_size); | |
5413 | ||
5414 | /* Current header size plus static size and dynamic size. */ | |
5415 | header_size += 2 * sizeof(u64); | |
5416 | ||
5417 | /* Do we fit in with the current stack dump size? */ | |
5418 | if ((u16) (header_size + stack_size) < header_size) { | |
5419 | /* | |
5420 | * If we overflow the maximum size for the sample, | |
5421 | * we customize the stack dump size to fit in. | |
5422 | */ | |
5423 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5424 | stack_size = round_up(stack_size, sizeof(u64)); | |
5425 | } | |
5426 | ||
5427 | return stack_size; | |
5428 | } | |
5429 | ||
5430 | static void | |
5431 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5432 | struct pt_regs *regs) | |
5433 | { | |
5434 | /* Case of a kernel thread, nothing to dump */ | |
5435 | if (!regs) { | |
5436 | u64 size = 0; | |
5437 | perf_output_put(handle, size); | |
5438 | } else { | |
5439 | unsigned long sp; | |
5440 | unsigned int rem; | |
5441 | u64 dyn_size; | |
5442 | ||
5443 | /* | |
5444 | * We dump: | |
5445 | * static size | |
5446 | * - the size requested by user or the best one we can fit | |
5447 | * in to the sample max size | |
5448 | * data | |
5449 | * - user stack dump data | |
5450 | * dynamic size | |
5451 | * - the actual dumped size | |
5452 | */ | |
5453 | ||
5454 | /* Static size. */ | |
5455 | perf_output_put(handle, dump_size); | |
5456 | ||
5457 | /* Data. */ | |
5458 | sp = perf_user_stack_pointer(regs); | |
5459 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5460 | dyn_size = dump_size - rem; | |
5461 | ||
5462 | perf_output_skip(handle, rem); | |
5463 | ||
5464 | /* Dynamic size. */ | |
5465 | perf_output_put(handle, dyn_size); | |
5466 | } | |
5467 | } | |
5468 | ||
c980d109 ACM |
5469 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5470 | struct perf_sample_data *data, | |
5471 | struct perf_event *event) | |
6844c09d ACM |
5472 | { |
5473 | u64 sample_type = event->attr.sample_type; | |
5474 | ||
5475 | data->type = sample_type; | |
5476 | header->size += event->id_header_size; | |
5477 | ||
5478 | if (sample_type & PERF_SAMPLE_TID) { | |
5479 | /* namespace issues */ | |
5480 | data->tid_entry.pid = perf_event_pid(event, current); | |
5481 | data->tid_entry.tid = perf_event_tid(event, current); | |
5482 | } | |
5483 | ||
5484 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5485 | data->time = perf_event_clock(event); |
6844c09d | 5486 | |
ff3d527c | 5487 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5488 | data->id = primary_event_id(event); |
5489 | ||
5490 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5491 | data->stream_id = event->id; | |
5492 | ||
5493 | if (sample_type & PERF_SAMPLE_CPU) { | |
5494 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5495 | data->cpu_entry.reserved = 0; | |
5496 | } | |
5497 | } | |
5498 | ||
76369139 FW |
5499 | void perf_event_header__init_id(struct perf_event_header *header, |
5500 | struct perf_sample_data *data, | |
5501 | struct perf_event *event) | |
c980d109 ACM |
5502 | { |
5503 | if (event->attr.sample_id_all) | |
5504 | __perf_event_header__init_id(header, data, event); | |
5505 | } | |
5506 | ||
5507 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5508 | struct perf_sample_data *data) | |
5509 | { | |
5510 | u64 sample_type = data->type; | |
5511 | ||
5512 | if (sample_type & PERF_SAMPLE_TID) | |
5513 | perf_output_put(handle, data->tid_entry); | |
5514 | ||
5515 | if (sample_type & PERF_SAMPLE_TIME) | |
5516 | perf_output_put(handle, data->time); | |
5517 | ||
5518 | if (sample_type & PERF_SAMPLE_ID) | |
5519 | perf_output_put(handle, data->id); | |
5520 | ||
5521 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5522 | perf_output_put(handle, data->stream_id); | |
5523 | ||
5524 | if (sample_type & PERF_SAMPLE_CPU) | |
5525 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5526 | |
5527 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5528 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5529 | } |
5530 | ||
76369139 FW |
5531 | void perf_event__output_id_sample(struct perf_event *event, |
5532 | struct perf_output_handle *handle, | |
5533 | struct perf_sample_data *sample) | |
c980d109 ACM |
5534 | { |
5535 | if (event->attr.sample_id_all) | |
5536 | __perf_event__output_id_sample(handle, sample); | |
5537 | } | |
5538 | ||
3dab77fb | 5539 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5540 | struct perf_event *event, |
5541 | u64 enabled, u64 running) | |
3dab77fb | 5542 | { |
cdd6c482 | 5543 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5544 | u64 values[4]; |
5545 | int n = 0; | |
5546 | ||
b5e58793 | 5547 | values[n++] = perf_event_count(event); |
3dab77fb | 5548 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5549 | values[n++] = enabled + |
cdd6c482 | 5550 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5551 | } |
5552 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5553 | values[n++] = running + |
cdd6c482 | 5554 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5555 | } |
5556 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5557 | values[n++] = primary_event_id(event); |
3dab77fb | 5558 | |
76369139 | 5559 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5560 | } |
5561 | ||
5562 | /* | |
cdd6c482 | 5563 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5564 | */ |
5565 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5566 | struct perf_event *event, |
5567 | u64 enabled, u64 running) | |
3dab77fb | 5568 | { |
cdd6c482 IM |
5569 | struct perf_event *leader = event->group_leader, *sub; |
5570 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5571 | u64 values[5]; |
5572 | int n = 0; | |
5573 | ||
5574 | values[n++] = 1 + leader->nr_siblings; | |
5575 | ||
5576 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5577 | values[n++] = enabled; |
3dab77fb PZ |
5578 | |
5579 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5580 | values[n++] = running; |
3dab77fb | 5581 | |
cdd6c482 | 5582 | if (leader != event) |
3dab77fb PZ |
5583 | leader->pmu->read(leader); |
5584 | ||
b5e58793 | 5585 | values[n++] = perf_event_count(leader); |
3dab77fb | 5586 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5587 | values[n++] = primary_event_id(leader); |
3dab77fb | 5588 | |
76369139 | 5589 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5590 | |
65abc865 | 5591 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5592 | n = 0; |
5593 | ||
6f5ab001 JO |
5594 | if ((sub != event) && |
5595 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5596 | sub->pmu->read(sub); |
5597 | ||
b5e58793 | 5598 | values[n++] = perf_event_count(sub); |
3dab77fb | 5599 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5600 | values[n++] = primary_event_id(sub); |
3dab77fb | 5601 | |
76369139 | 5602 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5603 | } |
5604 | } | |
5605 | ||
eed01528 SE |
5606 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5607 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5608 | ||
3dab77fb | 5609 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5610 | struct perf_event *event) |
3dab77fb | 5611 | { |
e3f3541c | 5612 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5613 | u64 read_format = event->attr.read_format; |
5614 | ||
5615 | /* | |
5616 | * compute total_time_enabled, total_time_running | |
5617 | * based on snapshot values taken when the event | |
5618 | * was last scheduled in. | |
5619 | * | |
5620 | * we cannot simply called update_context_time() | |
5621 | * because of locking issue as we are called in | |
5622 | * NMI context | |
5623 | */ | |
c4794295 | 5624 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5625 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5626 | |
cdd6c482 | 5627 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5628 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5629 | else |
eed01528 | 5630 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5631 | } |
5632 | ||
5622f295 MM |
5633 | void perf_output_sample(struct perf_output_handle *handle, |
5634 | struct perf_event_header *header, | |
5635 | struct perf_sample_data *data, | |
cdd6c482 | 5636 | struct perf_event *event) |
5622f295 MM |
5637 | { |
5638 | u64 sample_type = data->type; | |
5639 | ||
5640 | perf_output_put(handle, *header); | |
5641 | ||
ff3d527c AH |
5642 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5643 | perf_output_put(handle, data->id); | |
5644 | ||
5622f295 MM |
5645 | if (sample_type & PERF_SAMPLE_IP) |
5646 | perf_output_put(handle, data->ip); | |
5647 | ||
5648 | if (sample_type & PERF_SAMPLE_TID) | |
5649 | perf_output_put(handle, data->tid_entry); | |
5650 | ||
5651 | if (sample_type & PERF_SAMPLE_TIME) | |
5652 | perf_output_put(handle, data->time); | |
5653 | ||
5654 | if (sample_type & PERF_SAMPLE_ADDR) | |
5655 | perf_output_put(handle, data->addr); | |
5656 | ||
5657 | if (sample_type & PERF_SAMPLE_ID) | |
5658 | perf_output_put(handle, data->id); | |
5659 | ||
5660 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5661 | perf_output_put(handle, data->stream_id); | |
5662 | ||
5663 | if (sample_type & PERF_SAMPLE_CPU) | |
5664 | perf_output_put(handle, data->cpu_entry); | |
5665 | ||
5666 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5667 | perf_output_put(handle, data->period); | |
5668 | ||
5669 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5670 | perf_output_read(handle, event); |
5622f295 MM |
5671 | |
5672 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5673 | if (data->callchain) { | |
5674 | int size = 1; | |
5675 | ||
5676 | if (data->callchain) | |
5677 | size += data->callchain->nr; | |
5678 | ||
5679 | size *= sizeof(u64); | |
5680 | ||
76369139 | 5681 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5682 | } else { |
5683 | u64 nr = 0; | |
5684 | perf_output_put(handle, nr); | |
5685 | } | |
5686 | } | |
5687 | ||
5688 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5689 | struct perf_raw_record *raw = data->raw; |
5690 | ||
5691 | if (raw) { | |
5692 | struct perf_raw_frag *frag = &raw->frag; | |
5693 | ||
5694 | perf_output_put(handle, raw->size); | |
5695 | do { | |
5696 | if (frag->copy) { | |
5697 | __output_custom(handle, frag->copy, | |
5698 | frag->data, frag->size); | |
5699 | } else { | |
5700 | __output_copy(handle, frag->data, | |
5701 | frag->size); | |
5702 | } | |
5703 | if (perf_raw_frag_last(frag)) | |
5704 | break; | |
5705 | frag = frag->next; | |
5706 | } while (1); | |
5707 | if (frag->pad) | |
5708 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5709 | } else { |
5710 | struct { | |
5711 | u32 size; | |
5712 | u32 data; | |
5713 | } raw = { | |
5714 | .size = sizeof(u32), | |
5715 | .data = 0, | |
5716 | }; | |
5717 | perf_output_put(handle, raw); | |
5718 | } | |
5719 | } | |
a7ac67ea | 5720 | |
bce38cd5 SE |
5721 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5722 | if (data->br_stack) { | |
5723 | size_t size; | |
5724 | ||
5725 | size = data->br_stack->nr | |
5726 | * sizeof(struct perf_branch_entry); | |
5727 | ||
5728 | perf_output_put(handle, data->br_stack->nr); | |
5729 | perf_output_copy(handle, data->br_stack->entries, size); | |
5730 | } else { | |
5731 | /* | |
5732 | * we always store at least the value of nr | |
5733 | */ | |
5734 | u64 nr = 0; | |
5735 | perf_output_put(handle, nr); | |
5736 | } | |
5737 | } | |
4018994f JO |
5738 | |
5739 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5740 | u64 abi = data->regs_user.abi; | |
5741 | ||
5742 | /* | |
5743 | * If there are no regs to dump, notice it through | |
5744 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5745 | */ | |
5746 | perf_output_put(handle, abi); | |
5747 | ||
5748 | if (abi) { | |
5749 | u64 mask = event->attr.sample_regs_user; | |
5750 | perf_output_sample_regs(handle, | |
5751 | data->regs_user.regs, | |
5752 | mask); | |
5753 | } | |
5754 | } | |
c5ebcedb | 5755 | |
a5cdd40c | 5756 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5757 | perf_output_sample_ustack(handle, |
5758 | data->stack_user_size, | |
5759 | data->regs_user.regs); | |
a5cdd40c | 5760 | } |
c3feedf2 AK |
5761 | |
5762 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5763 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5764 | |
5765 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5766 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5767 | |
fdfbbd07 AK |
5768 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5769 | perf_output_put(handle, data->txn); | |
5770 | ||
60e2364e SE |
5771 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5772 | u64 abi = data->regs_intr.abi; | |
5773 | /* | |
5774 | * If there are no regs to dump, notice it through | |
5775 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5776 | */ | |
5777 | perf_output_put(handle, abi); | |
5778 | ||
5779 | if (abi) { | |
5780 | u64 mask = event->attr.sample_regs_intr; | |
5781 | ||
5782 | perf_output_sample_regs(handle, | |
5783 | data->regs_intr.regs, | |
5784 | mask); | |
5785 | } | |
5786 | } | |
5787 | ||
a5cdd40c PZ |
5788 | if (!event->attr.watermark) { |
5789 | int wakeup_events = event->attr.wakeup_events; | |
5790 | ||
5791 | if (wakeup_events) { | |
5792 | struct ring_buffer *rb = handle->rb; | |
5793 | int events = local_inc_return(&rb->events); | |
5794 | ||
5795 | if (events >= wakeup_events) { | |
5796 | local_sub(wakeup_events, &rb->events); | |
5797 | local_inc(&rb->wakeup); | |
5798 | } | |
5799 | } | |
5800 | } | |
5622f295 MM |
5801 | } |
5802 | ||
5803 | void perf_prepare_sample(struct perf_event_header *header, | |
5804 | struct perf_sample_data *data, | |
cdd6c482 | 5805 | struct perf_event *event, |
5622f295 | 5806 | struct pt_regs *regs) |
7b732a75 | 5807 | { |
cdd6c482 | 5808 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5809 | |
cdd6c482 | 5810 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5811 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5812 | |
5813 | header->misc = 0; | |
5814 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5815 | |
c980d109 | 5816 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5817 | |
c320c7b7 | 5818 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5819 | data->ip = perf_instruction_pointer(regs); |
5820 | ||
b23f3325 | 5821 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5822 | int size = 1; |
394ee076 | 5823 | |
e6dab5ff | 5824 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5825 | |
5826 | if (data->callchain) | |
5827 | size += data->callchain->nr; | |
5828 | ||
5829 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5830 | } |
5831 | ||
3a43ce68 | 5832 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
5833 | struct perf_raw_record *raw = data->raw; |
5834 | int size; | |
5835 | ||
5836 | if (raw) { | |
5837 | struct perf_raw_frag *frag = &raw->frag; | |
5838 | u32 sum = 0; | |
5839 | ||
5840 | do { | |
5841 | sum += frag->size; | |
5842 | if (perf_raw_frag_last(frag)) | |
5843 | break; | |
5844 | frag = frag->next; | |
5845 | } while (1); | |
5846 | ||
5847 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
5848 | raw->size = size - sizeof(u32); | |
5849 | frag->pad = raw->size - sum; | |
5850 | } else { | |
5851 | size = sizeof(u64); | |
5852 | } | |
a044560c | 5853 | |
7e3f977e | 5854 | header->size += size; |
7f453c24 | 5855 | } |
bce38cd5 SE |
5856 | |
5857 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5858 | int size = sizeof(u64); /* nr */ | |
5859 | if (data->br_stack) { | |
5860 | size += data->br_stack->nr | |
5861 | * sizeof(struct perf_branch_entry); | |
5862 | } | |
5863 | header->size += size; | |
5864 | } | |
4018994f | 5865 | |
2565711f | 5866 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5867 | perf_sample_regs_user(&data->regs_user, regs, |
5868 | &data->regs_user_copy); | |
2565711f | 5869 | |
4018994f JO |
5870 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5871 | /* regs dump ABI info */ | |
5872 | int size = sizeof(u64); | |
5873 | ||
4018994f JO |
5874 | if (data->regs_user.regs) { |
5875 | u64 mask = event->attr.sample_regs_user; | |
5876 | size += hweight64(mask) * sizeof(u64); | |
5877 | } | |
5878 | ||
5879 | header->size += size; | |
5880 | } | |
c5ebcedb JO |
5881 | |
5882 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5883 | /* | |
5884 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5885 | * processed as the last one or have additional check added | |
5886 | * in case new sample type is added, because we could eat | |
5887 | * up the rest of the sample size. | |
5888 | */ | |
c5ebcedb JO |
5889 | u16 stack_size = event->attr.sample_stack_user; |
5890 | u16 size = sizeof(u64); | |
5891 | ||
c5ebcedb | 5892 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5893 | data->regs_user.regs); |
c5ebcedb JO |
5894 | |
5895 | /* | |
5896 | * If there is something to dump, add space for the dump | |
5897 | * itself and for the field that tells the dynamic size, | |
5898 | * which is how many have been actually dumped. | |
5899 | */ | |
5900 | if (stack_size) | |
5901 | size += sizeof(u64) + stack_size; | |
5902 | ||
5903 | data->stack_user_size = stack_size; | |
5904 | header->size += size; | |
5905 | } | |
60e2364e SE |
5906 | |
5907 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
5908 | /* regs dump ABI info */ | |
5909 | int size = sizeof(u64); | |
5910 | ||
5911 | perf_sample_regs_intr(&data->regs_intr, regs); | |
5912 | ||
5913 | if (data->regs_intr.regs) { | |
5914 | u64 mask = event->attr.sample_regs_intr; | |
5915 | ||
5916 | size += hweight64(mask) * sizeof(u64); | |
5917 | } | |
5918 | ||
5919 | header->size += size; | |
5920 | } | |
5622f295 | 5921 | } |
7f453c24 | 5922 | |
9ecda41a WN |
5923 | static void __always_inline |
5924 | __perf_event_output(struct perf_event *event, | |
5925 | struct perf_sample_data *data, | |
5926 | struct pt_regs *regs, | |
5927 | int (*output_begin)(struct perf_output_handle *, | |
5928 | struct perf_event *, | |
5929 | unsigned int)) | |
5622f295 MM |
5930 | { |
5931 | struct perf_output_handle handle; | |
5932 | struct perf_event_header header; | |
689802b2 | 5933 | |
927c7a9e FW |
5934 | /* protect the callchain buffers */ |
5935 | rcu_read_lock(); | |
5936 | ||
cdd6c482 | 5937 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 5938 | |
9ecda41a | 5939 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 5940 | goto exit; |
0322cd6e | 5941 | |
cdd6c482 | 5942 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 5943 | |
8a057d84 | 5944 | perf_output_end(&handle); |
927c7a9e FW |
5945 | |
5946 | exit: | |
5947 | rcu_read_unlock(); | |
0322cd6e PZ |
5948 | } |
5949 | ||
9ecda41a WN |
5950 | void |
5951 | perf_event_output_forward(struct perf_event *event, | |
5952 | struct perf_sample_data *data, | |
5953 | struct pt_regs *regs) | |
5954 | { | |
5955 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
5956 | } | |
5957 | ||
5958 | void | |
5959 | perf_event_output_backward(struct perf_event *event, | |
5960 | struct perf_sample_data *data, | |
5961 | struct pt_regs *regs) | |
5962 | { | |
5963 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
5964 | } | |
5965 | ||
5966 | void | |
5967 | perf_event_output(struct perf_event *event, | |
5968 | struct perf_sample_data *data, | |
5969 | struct pt_regs *regs) | |
5970 | { | |
5971 | __perf_event_output(event, data, regs, perf_output_begin); | |
5972 | } | |
5973 | ||
38b200d6 | 5974 | /* |
cdd6c482 | 5975 | * read event_id |
38b200d6 PZ |
5976 | */ |
5977 | ||
5978 | struct perf_read_event { | |
5979 | struct perf_event_header header; | |
5980 | ||
5981 | u32 pid; | |
5982 | u32 tid; | |
38b200d6 PZ |
5983 | }; |
5984 | ||
5985 | static void | |
cdd6c482 | 5986 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
5987 | struct task_struct *task) |
5988 | { | |
5989 | struct perf_output_handle handle; | |
c980d109 | 5990 | struct perf_sample_data sample; |
dfc65094 | 5991 | struct perf_read_event read_event = { |
38b200d6 | 5992 | .header = { |
cdd6c482 | 5993 | .type = PERF_RECORD_READ, |
38b200d6 | 5994 | .misc = 0, |
c320c7b7 | 5995 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 5996 | }, |
cdd6c482 IM |
5997 | .pid = perf_event_pid(event, task), |
5998 | .tid = perf_event_tid(event, task), | |
38b200d6 | 5999 | }; |
3dab77fb | 6000 | int ret; |
38b200d6 | 6001 | |
c980d109 | 6002 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6003 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6004 | if (ret) |
6005 | return; | |
6006 | ||
dfc65094 | 6007 | perf_output_put(&handle, read_event); |
cdd6c482 | 6008 | perf_output_read(&handle, event); |
c980d109 | 6009 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6010 | |
38b200d6 PZ |
6011 | perf_output_end(&handle); |
6012 | } | |
6013 | ||
aab5b71e | 6014 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6015 | |
6016 | static void | |
aab5b71e PZ |
6017 | perf_iterate_ctx(struct perf_event_context *ctx, |
6018 | perf_iterate_f output, | |
b73e4fef | 6019 | void *data, bool all) |
52d857a8 JO |
6020 | { |
6021 | struct perf_event *event; | |
6022 | ||
6023 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6024 | if (!all) { |
6025 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6026 | continue; | |
6027 | if (!event_filter_match(event)) | |
6028 | continue; | |
6029 | } | |
6030 | ||
67516844 | 6031 | output(event, data); |
52d857a8 JO |
6032 | } |
6033 | } | |
6034 | ||
aab5b71e | 6035 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6036 | { |
6037 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6038 | struct perf_event *event; | |
6039 | ||
6040 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6041 | /* |
6042 | * Skip events that are not fully formed yet; ensure that | |
6043 | * if we observe event->ctx, both event and ctx will be | |
6044 | * complete enough. See perf_install_in_context(). | |
6045 | */ | |
6046 | if (!smp_load_acquire(&event->ctx)) | |
6047 | continue; | |
6048 | ||
f2fb6bef KL |
6049 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6050 | continue; | |
6051 | if (!event_filter_match(event)) | |
6052 | continue; | |
6053 | output(event, data); | |
6054 | } | |
6055 | } | |
6056 | ||
aab5b71e PZ |
6057 | /* |
6058 | * Iterate all events that need to receive side-band events. | |
6059 | * | |
6060 | * For new callers; ensure that account_pmu_sb_event() includes | |
6061 | * your event, otherwise it might not get delivered. | |
6062 | */ | |
52d857a8 | 6063 | static void |
aab5b71e | 6064 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6065 | struct perf_event_context *task_ctx) |
6066 | { | |
52d857a8 | 6067 | struct perf_event_context *ctx; |
52d857a8 JO |
6068 | int ctxn; |
6069 | ||
aab5b71e PZ |
6070 | rcu_read_lock(); |
6071 | preempt_disable(); | |
6072 | ||
4e93ad60 | 6073 | /* |
aab5b71e PZ |
6074 | * If we have task_ctx != NULL we only notify the task context itself. |
6075 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6076 | * context. |
6077 | */ | |
6078 | if (task_ctx) { | |
aab5b71e PZ |
6079 | perf_iterate_ctx(task_ctx, output, data, false); |
6080 | goto done; | |
4e93ad60 JO |
6081 | } |
6082 | ||
aab5b71e | 6083 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6084 | |
6085 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6086 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6087 | if (ctx) | |
aab5b71e | 6088 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6089 | } |
aab5b71e | 6090 | done: |
f2fb6bef | 6091 | preempt_enable(); |
52d857a8 | 6092 | rcu_read_unlock(); |
95ff4ca2 AS |
6093 | } |
6094 | ||
375637bc AS |
6095 | /* |
6096 | * Clear all file-based filters at exec, they'll have to be | |
6097 | * re-instated when/if these objects are mmapped again. | |
6098 | */ | |
6099 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6100 | { | |
6101 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6102 | struct perf_addr_filter *filter; | |
6103 | unsigned int restart = 0, count = 0; | |
6104 | unsigned long flags; | |
6105 | ||
6106 | if (!has_addr_filter(event)) | |
6107 | return; | |
6108 | ||
6109 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6110 | list_for_each_entry(filter, &ifh->list, entry) { | |
6111 | if (filter->inode) { | |
6112 | event->addr_filters_offs[count] = 0; | |
6113 | restart++; | |
6114 | } | |
6115 | ||
6116 | count++; | |
6117 | } | |
6118 | ||
6119 | if (restart) | |
6120 | event->addr_filters_gen++; | |
6121 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6122 | ||
6123 | if (restart) | |
6124 | perf_event_restart(event); | |
6125 | } | |
6126 | ||
6127 | void perf_event_exec(void) | |
6128 | { | |
6129 | struct perf_event_context *ctx; | |
6130 | int ctxn; | |
6131 | ||
6132 | rcu_read_lock(); | |
6133 | for_each_task_context_nr(ctxn) { | |
6134 | ctx = current->perf_event_ctxp[ctxn]; | |
6135 | if (!ctx) | |
6136 | continue; | |
6137 | ||
6138 | perf_event_enable_on_exec(ctxn); | |
6139 | ||
aab5b71e | 6140 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6141 | true); |
6142 | } | |
6143 | rcu_read_unlock(); | |
6144 | } | |
6145 | ||
95ff4ca2 AS |
6146 | struct remote_output { |
6147 | struct ring_buffer *rb; | |
6148 | int err; | |
6149 | }; | |
6150 | ||
6151 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6152 | { | |
6153 | struct perf_event *parent = event->parent; | |
6154 | struct remote_output *ro = data; | |
6155 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6156 | struct stop_event_data sd = { |
6157 | .event = event, | |
6158 | }; | |
95ff4ca2 AS |
6159 | |
6160 | if (!has_aux(event)) | |
6161 | return; | |
6162 | ||
6163 | if (!parent) | |
6164 | parent = event; | |
6165 | ||
6166 | /* | |
6167 | * In case of inheritance, it will be the parent that links to the | |
6168 | * ring-buffer, but it will be the child that's actually using it: | |
6169 | */ | |
6170 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6171 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6172 | } |
6173 | ||
6174 | static int __perf_pmu_output_stop(void *info) | |
6175 | { | |
6176 | struct perf_event *event = info; | |
6177 | struct pmu *pmu = event->pmu; | |
6178 | struct perf_cpu_context *cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); | |
6179 | struct remote_output ro = { | |
6180 | .rb = event->rb, | |
6181 | }; | |
6182 | ||
6183 | rcu_read_lock(); | |
aab5b71e | 6184 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6185 | if (cpuctx->task_ctx) |
aab5b71e | 6186 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6187 | &ro, false); |
95ff4ca2 AS |
6188 | rcu_read_unlock(); |
6189 | ||
6190 | return ro.err; | |
6191 | } | |
6192 | ||
6193 | static void perf_pmu_output_stop(struct perf_event *event) | |
6194 | { | |
6195 | struct perf_event *iter; | |
6196 | int err, cpu; | |
6197 | ||
6198 | restart: | |
6199 | rcu_read_lock(); | |
6200 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6201 | /* | |
6202 | * For per-CPU events, we need to make sure that neither they | |
6203 | * nor their children are running; for cpu==-1 events it's | |
6204 | * sufficient to stop the event itself if it's active, since | |
6205 | * it can't have children. | |
6206 | */ | |
6207 | cpu = iter->cpu; | |
6208 | if (cpu == -1) | |
6209 | cpu = READ_ONCE(iter->oncpu); | |
6210 | ||
6211 | if (cpu == -1) | |
6212 | continue; | |
6213 | ||
6214 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6215 | if (err == -EAGAIN) { | |
6216 | rcu_read_unlock(); | |
6217 | goto restart; | |
6218 | } | |
6219 | } | |
6220 | rcu_read_unlock(); | |
52d857a8 JO |
6221 | } |
6222 | ||
60313ebe | 6223 | /* |
9f498cc5 PZ |
6224 | * task tracking -- fork/exit |
6225 | * | |
13d7a241 | 6226 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6227 | */ |
6228 | ||
9f498cc5 | 6229 | struct perf_task_event { |
3a80b4a3 | 6230 | struct task_struct *task; |
cdd6c482 | 6231 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6232 | |
6233 | struct { | |
6234 | struct perf_event_header header; | |
6235 | ||
6236 | u32 pid; | |
6237 | u32 ppid; | |
9f498cc5 PZ |
6238 | u32 tid; |
6239 | u32 ptid; | |
393b2ad8 | 6240 | u64 time; |
cdd6c482 | 6241 | } event_id; |
60313ebe PZ |
6242 | }; |
6243 | ||
67516844 JO |
6244 | static int perf_event_task_match(struct perf_event *event) |
6245 | { | |
13d7a241 SE |
6246 | return event->attr.comm || event->attr.mmap || |
6247 | event->attr.mmap2 || event->attr.mmap_data || | |
6248 | event->attr.task; | |
67516844 JO |
6249 | } |
6250 | ||
cdd6c482 | 6251 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6252 | void *data) |
60313ebe | 6253 | { |
52d857a8 | 6254 | struct perf_task_event *task_event = data; |
60313ebe | 6255 | struct perf_output_handle handle; |
c980d109 | 6256 | struct perf_sample_data sample; |
9f498cc5 | 6257 | struct task_struct *task = task_event->task; |
c980d109 | 6258 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6259 | |
67516844 JO |
6260 | if (!perf_event_task_match(event)) |
6261 | return; | |
6262 | ||
c980d109 | 6263 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6264 | |
c980d109 | 6265 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6266 | task_event->event_id.header.size); |
ef60777c | 6267 | if (ret) |
c980d109 | 6268 | goto out; |
60313ebe | 6269 | |
cdd6c482 IM |
6270 | task_event->event_id.pid = perf_event_pid(event, task); |
6271 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6272 | |
cdd6c482 IM |
6273 | task_event->event_id.tid = perf_event_tid(event, task); |
6274 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6275 | |
34f43927 PZ |
6276 | task_event->event_id.time = perf_event_clock(event); |
6277 | ||
cdd6c482 | 6278 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6279 | |
c980d109 ACM |
6280 | perf_event__output_id_sample(event, &handle, &sample); |
6281 | ||
60313ebe | 6282 | perf_output_end(&handle); |
c980d109 ACM |
6283 | out: |
6284 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6285 | } |
6286 | ||
cdd6c482 IM |
6287 | static void perf_event_task(struct task_struct *task, |
6288 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6289 | int new) |
60313ebe | 6290 | { |
9f498cc5 | 6291 | struct perf_task_event task_event; |
60313ebe | 6292 | |
cdd6c482 IM |
6293 | if (!atomic_read(&nr_comm_events) && |
6294 | !atomic_read(&nr_mmap_events) && | |
6295 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6296 | return; |
6297 | ||
9f498cc5 | 6298 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6299 | .task = task, |
6300 | .task_ctx = task_ctx, | |
cdd6c482 | 6301 | .event_id = { |
60313ebe | 6302 | .header = { |
cdd6c482 | 6303 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6304 | .misc = 0, |
cdd6c482 | 6305 | .size = sizeof(task_event.event_id), |
60313ebe | 6306 | }, |
573402db PZ |
6307 | /* .pid */ |
6308 | /* .ppid */ | |
9f498cc5 PZ |
6309 | /* .tid */ |
6310 | /* .ptid */ | |
34f43927 | 6311 | /* .time */ |
60313ebe PZ |
6312 | }, |
6313 | }; | |
6314 | ||
aab5b71e | 6315 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6316 | &task_event, |
6317 | task_ctx); | |
9f498cc5 PZ |
6318 | } |
6319 | ||
cdd6c482 | 6320 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6321 | { |
cdd6c482 | 6322 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
6323 | } |
6324 | ||
8d1b2d93 PZ |
6325 | /* |
6326 | * comm tracking | |
6327 | */ | |
6328 | ||
6329 | struct perf_comm_event { | |
22a4f650 IM |
6330 | struct task_struct *task; |
6331 | char *comm; | |
8d1b2d93 PZ |
6332 | int comm_size; |
6333 | ||
6334 | struct { | |
6335 | struct perf_event_header header; | |
6336 | ||
6337 | u32 pid; | |
6338 | u32 tid; | |
cdd6c482 | 6339 | } event_id; |
8d1b2d93 PZ |
6340 | }; |
6341 | ||
67516844 JO |
6342 | static int perf_event_comm_match(struct perf_event *event) |
6343 | { | |
6344 | return event->attr.comm; | |
6345 | } | |
6346 | ||
cdd6c482 | 6347 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6348 | void *data) |
8d1b2d93 | 6349 | { |
52d857a8 | 6350 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6351 | struct perf_output_handle handle; |
c980d109 | 6352 | struct perf_sample_data sample; |
cdd6c482 | 6353 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6354 | int ret; |
6355 | ||
67516844 JO |
6356 | if (!perf_event_comm_match(event)) |
6357 | return; | |
6358 | ||
c980d109 ACM |
6359 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6360 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6361 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6362 | |
6363 | if (ret) | |
c980d109 | 6364 | goto out; |
8d1b2d93 | 6365 | |
cdd6c482 IM |
6366 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6367 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6368 | |
cdd6c482 | 6369 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6370 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6371 | comm_event->comm_size); |
c980d109 ACM |
6372 | |
6373 | perf_event__output_id_sample(event, &handle, &sample); | |
6374 | ||
8d1b2d93 | 6375 | perf_output_end(&handle); |
c980d109 ACM |
6376 | out: |
6377 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6378 | } |
6379 | ||
cdd6c482 | 6380 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6381 | { |
413ee3b4 | 6382 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6383 | unsigned int size; |
8d1b2d93 | 6384 | |
413ee3b4 | 6385 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6386 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6387 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6388 | |
6389 | comm_event->comm = comm; | |
6390 | comm_event->comm_size = size; | |
6391 | ||
cdd6c482 | 6392 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6393 | |
aab5b71e | 6394 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6395 | comm_event, |
6396 | NULL); | |
8d1b2d93 PZ |
6397 | } |
6398 | ||
82b89778 | 6399 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6400 | { |
9ee318a7 PZ |
6401 | struct perf_comm_event comm_event; |
6402 | ||
cdd6c482 | 6403 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6404 | return; |
a63eaf34 | 6405 | |
9ee318a7 | 6406 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6407 | .task = task, |
573402db PZ |
6408 | /* .comm */ |
6409 | /* .comm_size */ | |
cdd6c482 | 6410 | .event_id = { |
573402db | 6411 | .header = { |
cdd6c482 | 6412 | .type = PERF_RECORD_COMM, |
82b89778 | 6413 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6414 | /* .size */ |
6415 | }, | |
6416 | /* .pid */ | |
6417 | /* .tid */ | |
8d1b2d93 PZ |
6418 | }, |
6419 | }; | |
6420 | ||
cdd6c482 | 6421 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6422 | } |
6423 | ||
0a4a9391 PZ |
6424 | /* |
6425 | * mmap tracking | |
6426 | */ | |
6427 | ||
6428 | struct perf_mmap_event { | |
089dd79d PZ |
6429 | struct vm_area_struct *vma; |
6430 | ||
6431 | const char *file_name; | |
6432 | int file_size; | |
13d7a241 SE |
6433 | int maj, min; |
6434 | u64 ino; | |
6435 | u64 ino_generation; | |
f972eb63 | 6436 | u32 prot, flags; |
0a4a9391 PZ |
6437 | |
6438 | struct { | |
6439 | struct perf_event_header header; | |
6440 | ||
6441 | u32 pid; | |
6442 | u32 tid; | |
6443 | u64 start; | |
6444 | u64 len; | |
6445 | u64 pgoff; | |
cdd6c482 | 6446 | } event_id; |
0a4a9391 PZ |
6447 | }; |
6448 | ||
67516844 JO |
6449 | static int perf_event_mmap_match(struct perf_event *event, |
6450 | void *data) | |
6451 | { | |
6452 | struct perf_mmap_event *mmap_event = data; | |
6453 | struct vm_area_struct *vma = mmap_event->vma; | |
6454 | int executable = vma->vm_flags & VM_EXEC; | |
6455 | ||
6456 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6457 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6458 | } |
6459 | ||
cdd6c482 | 6460 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6461 | void *data) |
0a4a9391 | 6462 | { |
52d857a8 | 6463 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6464 | struct perf_output_handle handle; |
c980d109 | 6465 | struct perf_sample_data sample; |
cdd6c482 | 6466 | int size = mmap_event->event_id.header.size; |
c980d109 | 6467 | int ret; |
0a4a9391 | 6468 | |
67516844 JO |
6469 | if (!perf_event_mmap_match(event, data)) |
6470 | return; | |
6471 | ||
13d7a241 SE |
6472 | if (event->attr.mmap2) { |
6473 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6474 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6475 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6476 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6477 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6478 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6479 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6480 | } |
6481 | ||
c980d109 ACM |
6482 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6483 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6484 | mmap_event->event_id.header.size); |
0a4a9391 | 6485 | if (ret) |
c980d109 | 6486 | goto out; |
0a4a9391 | 6487 | |
cdd6c482 IM |
6488 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6489 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6490 | |
cdd6c482 | 6491 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6492 | |
6493 | if (event->attr.mmap2) { | |
6494 | perf_output_put(&handle, mmap_event->maj); | |
6495 | perf_output_put(&handle, mmap_event->min); | |
6496 | perf_output_put(&handle, mmap_event->ino); | |
6497 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6498 | perf_output_put(&handle, mmap_event->prot); |
6499 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6500 | } |
6501 | ||
76369139 | 6502 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6503 | mmap_event->file_size); |
c980d109 ACM |
6504 | |
6505 | perf_event__output_id_sample(event, &handle, &sample); | |
6506 | ||
78d613eb | 6507 | perf_output_end(&handle); |
c980d109 ACM |
6508 | out: |
6509 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6510 | } |
6511 | ||
cdd6c482 | 6512 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6513 | { |
089dd79d PZ |
6514 | struct vm_area_struct *vma = mmap_event->vma; |
6515 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6516 | int maj = 0, min = 0; |
6517 | u64 ino = 0, gen = 0; | |
f972eb63 | 6518 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6519 | unsigned int size; |
6520 | char tmp[16]; | |
6521 | char *buf = NULL; | |
2c42cfbf | 6522 | char *name; |
413ee3b4 | 6523 | |
0a4a9391 | 6524 | if (file) { |
13d7a241 SE |
6525 | struct inode *inode; |
6526 | dev_t dev; | |
3ea2f2b9 | 6527 | |
2c42cfbf | 6528 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6529 | if (!buf) { |
c7e548b4 ON |
6530 | name = "//enomem"; |
6531 | goto cpy_name; | |
0a4a9391 | 6532 | } |
413ee3b4 | 6533 | /* |
3ea2f2b9 | 6534 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6535 | * need to add enough zero bytes after the string to handle |
6536 | * the 64bit alignment we do later. | |
6537 | */ | |
9bf39ab2 | 6538 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6539 | if (IS_ERR(name)) { |
c7e548b4 ON |
6540 | name = "//toolong"; |
6541 | goto cpy_name; | |
0a4a9391 | 6542 | } |
13d7a241 SE |
6543 | inode = file_inode(vma->vm_file); |
6544 | dev = inode->i_sb->s_dev; | |
6545 | ino = inode->i_ino; | |
6546 | gen = inode->i_generation; | |
6547 | maj = MAJOR(dev); | |
6548 | min = MINOR(dev); | |
f972eb63 PZ |
6549 | |
6550 | if (vma->vm_flags & VM_READ) | |
6551 | prot |= PROT_READ; | |
6552 | if (vma->vm_flags & VM_WRITE) | |
6553 | prot |= PROT_WRITE; | |
6554 | if (vma->vm_flags & VM_EXEC) | |
6555 | prot |= PROT_EXEC; | |
6556 | ||
6557 | if (vma->vm_flags & VM_MAYSHARE) | |
6558 | flags = MAP_SHARED; | |
6559 | else | |
6560 | flags = MAP_PRIVATE; | |
6561 | ||
6562 | if (vma->vm_flags & VM_DENYWRITE) | |
6563 | flags |= MAP_DENYWRITE; | |
6564 | if (vma->vm_flags & VM_MAYEXEC) | |
6565 | flags |= MAP_EXECUTABLE; | |
6566 | if (vma->vm_flags & VM_LOCKED) | |
6567 | flags |= MAP_LOCKED; | |
6568 | if (vma->vm_flags & VM_HUGETLB) | |
6569 | flags |= MAP_HUGETLB; | |
6570 | ||
c7e548b4 | 6571 | goto got_name; |
0a4a9391 | 6572 | } else { |
fbe26abe JO |
6573 | if (vma->vm_ops && vma->vm_ops->name) { |
6574 | name = (char *) vma->vm_ops->name(vma); | |
6575 | if (name) | |
6576 | goto cpy_name; | |
6577 | } | |
6578 | ||
2c42cfbf | 6579 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6580 | if (name) |
6581 | goto cpy_name; | |
089dd79d | 6582 | |
32c5fb7e | 6583 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6584 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6585 | name = "[heap]"; |
6586 | goto cpy_name; | |
32c5fb7e ON |
6587 | } |
6588 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6589 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6590 | name = "[stack]"; |
6591 | goto cpy_name; | |
089dd79d PZ |
6592 | } |
6593 | ||
c7e548b4 ON |
6594 | name = "//anon"; |
6595 | goto cpy_name; | |
0a4a9391 PZ |
6596 | } |
6597 | ||
c7e548b4 ON |
6598 | cpy_name: |
6599 | strlcpy(tmp, name, sizeof(tmp)); | |
6600 | name = tmp; | |
0a4a9391 | 6601 | got_name: |
2c42cfbf PZ |
6602 | /* |
6603 | * Since our buffer works in 8 byte units we need to align our string | |
6604 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6605 | * zero'd out to avoid leaking random bits to userspace. | |
6606 | */ | |
6607 | size = strlen(name)+1; | |
6608 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6609 | name[size++] = '\0'; | |
0a4a9391 PZ |
6610 | |
6611 | mmap_event->file_name = name; | |
6612 | mmap_event->file_size = size; | |
13d7a241 SE |
6613 | mmap_event->maj = maj; |
6614 | mmap_event->min = min; | |
6615 | mmap_event->ino = ino; | |
6616 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6617 | mmap_event->prot = prot; |
6618 | mmap_event->flags = flags; | |
0a4a9391 | 6619 | |
2fe85427 SE |
6620 | if (!(vma->vm_flags & VM_EXEC)) |
6621 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6622 | ||
cdd6c482 | 6623 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6624 | |
aab5b71e | 6625 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6626 | mmap_event, |
6627 | NULL); | |
665c2142 | 6628 | |
0a4a9391 PZ |
6629 | kfree(buf); |
6630 | } | |
6631 | ||
375637bc AS |
6632 | /* |
6633 | * Check whether inode and address range match filter criteria. | |
6634 | */ | |
6635 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6636 | struct file *file, unsigned long offset, | |
6637 | unsigned long size) | |
6638 | { | |
6639 | if (filter->inode != file->f_inode) | |
6640 | return false; | |
6641 | ||
6642 | if (filter->offset > offset + size) | |
6643 | return false; | |
6644 | ||
6645 | if (filter->offset + filter->size < offset) | |
6646 | return false; | |
6647 | ||
6648 | return true; | |
6649 | } | |
6650 | ||
6651 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6652 | { | |
6653 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6654 | struct vm_area_struct *vma = data; | |
6655 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6656 | struct file *file = vma->vm_file; | |
6657 | struct perf_addr_filter *filter; | |
6658 | unsigned int restart = 0, count = 0; | |
6659 | ||
6660 | if (!has_addr_filter(event)) | |
6661 | return; | |
6662 | ||
6663 | if (!file) | |
6664 | return; | |
6665 | ||
6666 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6667 | list_for_each_entry(filter, &ifh->list, entry) { | |
6668 | if (perf_addr_filter_match(filter, file, off, | |
6669 | vma->vm_end - vma->vm_start)) { | |
6670 | event->addr_filters_offs[count] = vma->vm_start; | |
6671 | restart++; | |
6672 | } | |
6673 | ||
6674 | count++; | |
6675 | } | |
6676 | ||
6677 | if (restart) | |
6678 | event->addr_filters_gen++; | |
6679 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6680 | ||
6681 | if (restart) | |
6682 | perf_event_restart(event); | |
6683 | } | |
6684 | ||
6685 | /* | |
6686 | * Adjust all task's events' filters to the new vma | |
6687 | */ | |
6688 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6689 | { | |
6690 | struct perf_event_context *ctx; | |
6691 | int ctxn; | |
6692 | ||
12b40a23 MP |
6693 | /* |
6694 | * Data tracing isn't supported yet and as such there is no need | |
6695 | * to keep track of anything that isn't related to executable code: | |
6696 | */ | |
6697 | if (!(vma->vm_flags & VM_EXEC)) | |
6698 | return; | |
6699 | ||
375637bc AS |
6700 | rcu_read_lock(); |
6701 | for_each_task_context_nr(ctxn) { | |
6702 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
6703 | if (!ctx) | |
6704 | continue; | |
6705 | ||
aab5b71e | 6706 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
6707 | } |
6708 | rcu_read_unlock(); | |
6709 | } | |
6710 | ||
3af9e859 | 6711 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6712 | { |
9ee318a7 PZ |
6713 | struct perf_mmap_event mmap_event; |
6714 | ||
cdd6c482 | 6715 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6716 | return; |
6717 | ||
6718 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6719 | .vma = vma, |
573402db PZ |
6720 | /* .file_name */ |
6721 | /* .file_size */ | |
cdd6c482 | 6722 | .event_id = { |
573402db | 6723 | .header = { |
cdd6c482 | 6724 | .type = PERF_RECORD_MMAP, |
39447b38 | 6725 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6726 | /* .size */ |
6727 | }, | |
6728 | /* .pid */ | |
6729 | /* .tid */ | |
089dd79d PZ |
6730 | .start = vma->vm_start, |
6731 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6732 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6733 | }, |
13d7a241 SE |
6734 | /* .maj (attr_mmap2 only) */ |
6735 | /* .min (attr_mmap2 only) */ | |
6736 | /* .ino (attr_mmap2 only) */ | |
6737 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6738 | /* .prot (attr_mmap2 only) */ |
6739 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6740 | }; |
6741 | ||
375637bc | 6742 | perf_addr_filters_adjust(vma); |
cdd6c482 | 6743 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6744 | } |
6745 | ||
68db7e98 AS |
6746 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6747 | unsigned long size, u64 flags) | |
6748 | { | |
6749 | struct perf_output_handle handle; | |
6750 | struct perf_sample_data sample; | |
6751 | struct perf_aux_event { | |
6752 | struct perf_event_header header; | |
6753 | u64 offset; | |
6754 | u64 size; | |
6755 | u64 flags; | |
6756 | } rec = { | |
6757 | .header = { | |
6758 | .type = PERF_RECORD_AUX, | |
6759 | .misc = 0, | |
6760 | .size = sizeof(rec), | |
6761 | }, | |
6762 | .offset = head, | |
6763 | .size = size, | |
6764 | .flags = flags, | |
6765 | }; | |
6766 | int ret; | |
6767 | ||
6768 | perf_event_header__init_id(&rec.header, &sample, event); | |
6769 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6770 | ||
6771 | if (ret) | |
6772 | return; | |
6773 | ||
6774 | perf_output_put(&handle, rec); | |
6775 | perf_event__output_id_sample(event, &handle, &sample); | |
6776 | ||
6777 | perf_output_end(&handle); | |
6778 | } | |
6779 | ||
f38b0dbb KL |
6780 | /* |
6781 | * Lost/dropped samples logging | |
6782 | */ | |
6783 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6784 | { | |
6785 | struct perf_output_handle handle; | |
6786 | struct perf_sample_data sample; | |
6787 | int ret; | |
6788 | ||
6789 | struct { | |
6790 | struct perf_event_header header; | |
6791 | u64 lost; | |
6792 | } lost_samples_event = { | |
6793 | .header = { | |
6794 | .type = PERF_RECORD_LOST_SAMPLES, | |
6795 | .misc = 0, | |
6796 | .size = sizeof(lost_samples_event), | |
6797 | }, | |
6798 | .lost = lost, | |
6799 | }; | |
6800 | ||
6801 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6802 | ||
6803 | ret = perf_output_begin(&handle, event, | |
6804 | lost_samples_event.header.size); | |
6805 | if (ret) | |
6806 | return; | |
6807 | ||
6808 | perf_output_put(&handle, lost_samples_event); | |
6809 | perf_event__output_id_sample(event, &handle, &sample); | |
6810 | perf_output_end(&handle); | |
6811 | } | |
6812 | ||
45ac1403 AH |
6813 | /* |
6814 | * context_switch tracking | |
6815 | */ | |
6816 | ||
6817 | struct perf_switch_event { | |
6818 | struct task_struct *task; | |
6819 | struct task_struct *next_prev; | |
6820 | ||
6821 | struct { | |
6822 | struct perf_event_header header; | |
6823 | u32 next_prev_pid; | |
6824 | u32 next_prev_tid; | |
6825 | } event_id; | |
6826 | }; | |
6827 | ||
6828 | static int perf_event_switch_match(struct perf_event *event) | |
6829 | { | |
6830 | return event->attr.context_switch; | |
6831 | } | |
6832 | ||
6833 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6834 | { | |
6835 | struct perf_switch_event *se = data; | |
6836 | struct perf_output_handle handle; | |
6837 | struct perf_sample_data sample; | |
6838 | int ret; | |
6839 | ||
6840 | if (!perf_event_switch_match(event)) | |
6841 | return; | |
6842 | ||
6843 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6844 | if (event->ctx->task) { | |
6845 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6846 | se->event_id.header.size = sizeof(se->event_id.header); | |
6847 | } else { | |
6848 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6849 | se->event_id.header.size = sizeof(se->event_id); | |
6850 | se->event_id.next_prev_pid = | |
6851 | perf_event_pid(event, se->next_prev); | |
6852 | se->event_id.next_prev_tid = | |
6853 | perf_event_tid(event, se->next_prev); | |
6854 | } | |
6855 | ||
6856 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6857 | ||
6858 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6859 | if (ret) | |
6860 | return; | |
6861 | ||
6862 | if (event->ctx->task) | |
6863 | perf_output_put(&handle, se->event_id.header); | |
6864 | else | |
6865 | perf_output_put(&handle, se->event_id); | |
6866 | ||
6867 | perf_event__output_id_sample(event, &handle, &sample); | |
6868 | ||
6869 | perf_output_end(&handle); | |
6870 | } | |
6871 | ||
6872 | static void perf_event_switch(struct task_struct *task, | |
6873 | struct task_struct *next_prev, bool sched_in) | |
6874 | { | |
6875 | struct perf_switch_event switch_event; | |
6876 | ||
6877 | /* N.B. caller checks nr_switch_events != 0 */ | |
6878 | ||
6879 | switch_event = (struct perf_switch_event){ | |
6880 | .task = task, | |
6881 | .next_prev = next_prev, | |
6882 | .event_id = { | |
6883 | .header = { | |
6884 | /* .type */ | |
6885 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6886 | /* .size */ | |
6887 | }, | |
6888 | /* .next_prev_pid */ | |
6889 | /* .next_prev_tid */ | |
6890 | }, | |
6891 | }; | |
6892 | ||
aab5b71e | 6893 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
6894 | &switch_event, |
6895 | NULL); | |
6896 | } | |
6897 | ||
a78ac325 PZ |
6898 | /* |
6899 | * IRQ throttle logging | |
6900 | */ | |
6901 | ||
cdd6c482 | 6902 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
6903 | { |
6904 | struct perf_output_handle handle; | |
c980d109 | 6905 | struct perf_sample_data sample; |
a78ac325 PZ |
6906 | int ret; |
6907 | ||
6908 | struct { | |
6909 | struct perf_event_header header; | |
6910 | u64 time; | |
cca3f454 | 6911 | u64 id; |
7f453c24 | 6912 | u64 stream_id; |
a78ac325 PZ |
6913 | } throttle_event = { |
6914 | .header = { | |
cdd6c482 | 6915 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
6916 | .misc = 0, |
6917 | .size = sizeof(throttle_event), | |
6918 | }, | |
34f43927 | 6919 | .time = perf_event_clock(event), |
cdd6c482 IM |
6920 | .id = primary_event_id(event), |
6921 | .stream_id = event->id, | |
a78ac325 PZ |
6922 | }; |
6923 | ||
966ee4d6 | 6924 | if (enable) |
cdd6c482 | 6925 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 6926 | |
c980d109 ACM |
6927 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
6928 | ||
6929 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6930 | throttle_event.header.size); |
a78ac325 PZ |
6931 | if (ret) |
6932 | return; | |
6933 | ||
6934 | perf_output_put(&handle, throttle_event); | |
c980d109 | 6935 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
6936 | perf_output_end(&handle); |
6937 | } | |
6938 | ||
ec0d7729 AS |
6939 | static void perf_log_itrace_start(struct perf_event *event) |
6940 | { | |
6941 | struct perf_output_handle handle; | |
6942 | struct perf_sample_data sample; | |
6943 | struct perf_aux_event { | |
6944 | struct perf_event_header header; | |
6945 | u32 pid; | |
6946 | u32 tid; | |
6947 | } rec; | |
6948 | int ret; | |
6949 | ||
6950 | if (event->parent) | |
6951 | event = event->parent; | |
6952 | ||
6953 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
6954 | event->hw.itrace_started) | |
6955 | return; | |
6956 | ||
ec0d7729 AS |
6957 | rec.header.type = PERF_RECORD_ITRACE_START; |
6958 | rec.header.misc = 0; | |
6959 | rec.header.size = sizeof(rec); | |
6960 | rec.pid = perf_event_pid(event, current); | |
6961 | rec.tid = perf_event_tid(event, current); | |
6962 | ||
6963 | perf_event_header__init_id(&rec.header, &sample, event); | |
6964 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6965 | ||
6966 | if (ret) | |
6967 | return; | |
6968 | ||
6969 | perf_output_put(&handle, rec); | |
6970 | perf_event__output_id_sample(event, &handle, &sample); | |
6971 | ||
6972 | perf_output_end(&handle); | |
6973 | } | |
6974 | ||
f6c7d5fe | 6975 | /* |
cdd6c482 | 6976 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
6977 | */ |
6978 | ||
a8b0ca17 | 6979 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6980 | int throttle, struct perf_sample_data *data, |
6981 | struct pt_regs *regs) | |
f6c7d5fe | 6982 | { |
cdd6c482 IM |
6983 | int events = atomic_read(&event->event_limit); |
6984 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 6985 | u64 seq; |
79f14641 PZ |
6986 | int ret = 0; |
6987 | ||
96398826 PZ |
6988 | /* |
6989 | * Non-sampling counters might still use the PMI to fold short | |
6990 | * hardware counters, ignore those. | |
6991 | */ | |
6992 | if (unlikely(!is_sampling_event(event))) | |
6993 | return 0; | |
6994 | ||
e050e3f0 SE |
6995 | seq = __this_cpu_read(perf_throttled_seq); |
6996 | if (seq != hwc->interrupts_seq) { | |
6997 | hwc->interrupts_seq = seq; | |
6998 | hwc->interrupts = 1; | |
6999 | } else { | |
7000 | hwc->interrupts++; | |
7001 | if (unlikely(throttle | |
7002 | && hwc->interrupts >= max_samples_per_tick)) { | |
7003 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7004 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7005 | hwc->interrupts = MAX_INTERRUPTS; |
7006 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7007 | ret = 1; |
7008 | } | |
e050e3f0 | 7009 | } |
60db5e09 | 7010 | |
cdd6c482 | 7011 | if (event->attr.freq) { |
def0a9b2 | 7012 | u64 now = perf_clock(); |
abd50713 | 7013 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7014 | |
abd50713 | 7015 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7016 | |
abd50713 | 7017 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7018 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7019 | } |
7020 | ||
2023b359 PZ |
7021 | /* |
7022 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7023 | * events |
2023b359 PZ |
7024 | */ |
7025 | ||
cdd6c482 IM |
7026 | event->pending_kill = POLL_IN; |
7027 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7028 | ret = 1; |
cdd6c482 | 7029 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
7030 | event->pending_disable = 1; |
7031 | irq_work_queue(&event->pending); | |
79f14641 PZ |
7032 | } |
7033 | ||
1879445d | 7034 | event->overflow_handler(event, data, regs); |
453f19ee | 7035 | |
fed66e2c | 7036 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7037 | event->pending_wakeup = 1; |
7038 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7039 | } |
7040 | ||
79f14641 | 7041 | return ret; |
f6c7d5fe PZ |
7042 | } |
7043 | ||
a8b0ca17 | 7044 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7045 | struct perf_sample_data *data, |
7046 | struct pt_regs *regs) | |
850bc73f | 7047 | { |
a8b0ca17 | 7048 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7049 | } |
7050 | ||
15dbf27c | 7051 | /* |
cdd6c482 | 7052 | * Generic software event infrastructure |
15dbf27c PZ |
7053 | */ |
7054 | ||
b28ab83c PZ |
7055 | struct swevent_htable { |
7056 | struct swevent_hlist *swevent_hlist; | |
7057 | struct mutex hlist_mutex; | |
7058 | int hlist_refcount; | |
7059 | ||
7060 | /* Recursion avoidance in each contexts */ | |
7061 | int recursion[PERF_NR_CONTEXTS]; | |
7062 | }; | |
7063 | ||
7064 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7065 | ||
7b4b6658 | 7066 | /* |
cdd6c482 IM |
7067 | * We directly increment event->count and keep a second value in |
7068 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7069 | * is kept in the range [-sample_period, 0] so that we can use the |
7070 | * sign as trigger. | |
7071 | */ | |
7072 | ||
ab573844 | 7073 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7074 | { |
cdd6c482 | 7075 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7076 | u64 period = hwc->last_period; |
7077 | u64 nr, offset; | |
7078 | s64 old, val; | |
7079 | ||
7080 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7081 | |
7082 | again: | |
e7850595 | 7083 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7084 | if (val < 0) |
7085 | return 0; | |
15dbf27c | 7086 | |
7b4b6658 PZ |
7087 | nr = div64_u64(period + val, period); |
7088 | offset = nr * period; | |
7089 | val -= offset; | |
e7850595 | 7090 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7091 | goto again; |
15dbf27c | 7092 | |
7b4b6658 | 7093 | return nr; |
15dbf27c PZ |
7094 | } |
7095 | ||
0cff784a | 7096 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7097 | struct perf_sample_data *data, |
5622f295 | 7098 | struct pt_regs *regs) |
15dbf27c | 7099 | { |
cdd6c482 | 7100 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7101 | int throttle = 0; |
15dbf27c | 7102 | |
0cff784a PZ |
7103 | if (!overflow) |
7104 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7105 | |
7b4b6658 PZ |
7106 | if (hwc->interrupts == MAX_INTERRUPTS) |
7107 | return; | |
15dbf27c | 7108 | |
7b4b6658 | 7109 | for (; overflow; overflow--) { |
a8b0ca17 | 7110 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7111 | data, regs)) { |
7b4b6658 PZ |
7112 | /* |
7113 | * We inhibit the overflow from happening when | |
7114 | * hwc->interrupts == MAX_INTERRUPTS. | |
7115 | */ | |
7116 | break; | |
7117 | } | |
cf450a73 | 7118 | throttle = 1; |
7b4b6658 | 7119 | } |
15dbf27c PZ |
7120 | } |
7121 | ||
a4eaf7f1 | 7122 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7123 | struct perf_sample_data *data, |
5622f295 | 7124 | struct pt_regs *regs) |
7b4b6658 | 7125 | { |
cdd6c482 | 7126 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7127 | |
e7850595 | 7128 | local64_add(nr, &event->count); |
d6d020e9 | 7129 | |
0cff784a PZ |
7130 | if (!regs) |
7131 | return; | |
7132 | ||
6c7e550f | 7133 | if (!is_sampling_event(event)) |
7b4b6658 | 7134 | return; |
d6d020e9 | 7135 | |
5d81e5cf AV |
7136 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7137 | data->period = nr; | |
7138 | return perf_swevent_overflow(event, 1, data, regs); | |
7139 | } else | |
7140 | data->period = event->hw.last_period; | |
7141 | ||
0cff784a | 7142 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7143 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7144 | |
e7850595 | 7145 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7146 | return; |
df1a132b | 7147 | |
a8b0ca17 | 7148 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7149 | } |
7150 | ||
f5ffe02e FW |
7151 | static int perf_exclude_event(struct perf_event *event, |
7152 | struct pt_regs *regs) | |
7153 | { | |
a4eaf7f1 | 7154 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7155 | return 1; |
a4eaf7f1 | 7156 | |
f5ffe02e FW |
7157 | if (regs) { |
7158 | if (event->attr.exclude_user && user_mode(regs)) | |
7159 | return 1; | |
7160 | ||
7161 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7162 | return 1; | |
7163 | } | |
7164 | ||
7165 | return 0; | |
7166 | } | |
7167 | ||
cdd6c482 | 7168 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7169 | enum perf_type_id type, |
6fb2915d LZ |
7170 | u32 event_id, |
7171 | struct perf_sample_data *data, | |
7172 | struct pt_regs *regs) | |
15dbf27c | 7173 | { |
cdd6c482 | 7174 | if (event->attr.type != type) |
a21ca2ca | 7175 | return 0; |
f5ffe02e | 7176 | |
cdd6c482 | 7177 | if (event->attr.config != event_id) |
15dbf27c PZ |
7178 | return 0; |
7179 | ||
f5ffe02e FW |
7180 | if (perf_exclude_event(event, regs)) |
7181 | return 0; | |
15dbf27c PZ |
7182 | |
7183 | return 1; | |
7184 | } | |
7185 | ||
76e1d904 FW |
7186 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7187 | { | |
7188 | u64 val = event_id | (type << 32); | |
7189 | ||
7190 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7191 | } | |
7192 | ||
49f135ed FW |
7193 | static inline struct hlist_head * |
7194 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7195 | { |
49f135ed FW |
7196 | u64 hash = swevent_hash(type, event_id); |
7197 | ||
7198 | return &hlist->heads[hash]; | |
7199 | } | |
76e1d904 | 7200 | |
49f135ed FW |
7201 | /* For the read side: events when they trigger */ |
7202 | static inline struct hlist_head * | |
b28ab83c | 7203 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7204 | { |
7205 | struct swevent_hlist *hlist; | |
76e1d904 | 7206 | |
b28ab83c | 7207 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7208 | if (!hlist) |
7209 | return NULL; | |
7210 | ||
49f135ed FW |
7211 | return __find_swevent_head(hlist, type, event_id); |
7212 | } | |
7213 | ||
7214 | /* For the event head insertion and removal in the hlist */ | |
7215 | static inline struct hlist_head * | |
b28ab83c | 7216 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7217 | { |
7218 | struct swevent_hlist *hlist; | |
7219 | u32 event_id = event->attr.config; | |
7220 | u64 type = event->attr.type; | |
7221 | ||
7222 | /* | |
7223 | * Event scheduling is always serialized against hlist allocation | |
7224 | * and release. Which makes the protected version suitable here. | |
7225 | * The context lock guarantees that. | |
7226 | */ | |
b28ab83c | 7227 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7228 | lockdep_is_held(&event->ctx->lock)); |
7229 | if (!hlist) | |
7230 | return NULL; | |
7231 | ||
7232 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7233 | } |
7234 | ||
7235 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7236 | u64 nr, |
76e1d904 FW |
7237 | struct perf_sample_data *data, |
7238 | struct pt_regs *regs) | |
15dbf27c | 7239 | { |
4a32fea9 | 7240 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7241 | struct perf_event *event; |
76e1d904 | 7242 | struct hlist_head *head; |
15dbf27c | 7243 | |
76e1d904 | 7244 | rcu_read_lock(); |
b28ab83c | 7245 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7246 | if (!head) |
7247 | goto end; | |
7248 | ||
b67bfe0d | 7249 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7250 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7251 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7252 | } |
76e1d904 FW |
7253 | end: |
7254 | rcu_read_unlock(); | |
15dbf27c PZ |
7255 | } |
7256 | ||
86038c5e PZI |
7257 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7258 | ||
4ed7c92d | 7259 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7260 | { |
4a32fea9 | 7261 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7262 | |
b28ab83c | 7263 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7264 | } |
645e8cc0 | 7265 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7266 | |
98b5c2c6 | 7267 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7268 | { |
4a32fea9 | 7269 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7270 | |
b28ab83c | 7271 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7272 | } |
15dbf27c | 7273 | |
86038c5e | 7274 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7275 | { |
a4234bfc | 7276 | struct perf_sample_data data; |
4ed7c92d | 7277 | |
86038c5e | 7278 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7279 | return; |
a4234bfc | 7280 | |
fd0d000b | 7281 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7282 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7283 | } |
7284 | ||
7285 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7286 | { | |
7287 | int rctx; | |
7288 | ||
7289 | preempt_disable_notrace(); | |
7290 | rctx = perf_swevent_get_recursion_context(); | |
7291 | if (unlikely(rctx < 0)) | |
7292 | goto fail; | |
7293 | ||
7294 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7295 | |
7296 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7297 | fail: |
1c024eca | 7298 | preempt_enable_notrace(); |
b8e83514 PZ |
7299 | } |
7300 | ||
cdd6c482 | 7301 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7302 | { |
15dbf27c PZ |
7303 | } |
7304 | ||
a4eaf7f1 | 7305 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7306 | { |
4a32fea9 | 7307 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7308 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7309 | struct hlist_head *head; |
7310 | ||
6c7e550f | 7311 | if (is_sampling_event(event)) { |
7b4b6658 | 7312 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7313 | perf_swevent_set_period(event); |
7b4b6658 | 7314 | } |
76e1d904 | 7315 | |
a4eaf7f1 PZ |
7316 | hwc->state = !(flags & PERF_EF_START); |
7317 | ||
b28ab83c | 7318 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7319 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7320 | return -EINVAL; |
7321 | ||
7322 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7323 | perf_event_update_userpage(event); |
76e1d904 | 7324 | |
15dbf27c PZ |
7325 | return 0; |
7326 | } | |
7327 | ||
a4eaf7f1 | 7328 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7329 | { |
76e1d904 | 7330 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7331 | } |
7332 | ||
a4eaf7f1 | 7333 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7334 | { |
a4eaf7f1 | 7335 | event->hw.state = 0; |
d6d020e9 | 7336 | } |
aa9c4c0f | 7337 | |
a4eaf7f1 | 7338 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7339 | { |
a4eaf7f1 | 7340 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7341 | } |
7342 | ||
49f135ed FW |
7343 | /* Deref the hlist from the update side */ |
7344 | static inline struct swevent_hlist * | |
b28ab83c | 7345 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7346 | { |
b28ab83c PZ |
7347 | return rcu_dereference_protected(swhash->swevent_hlist, |
7348 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7349 | } |
7350 | ||
b28ab83c | 7351 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7352 | { |
b28ab83c | 7353 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7354 | |
49f135ed | 7355 | if (!hlist) |
76e1d904 FW |
7356 | return; |
7357 | ||
70691d4a | 7358 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7359 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7360 | } |
7361 | ||
3b364d7b | 7362 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7363 | { |
b28ab83c | 7364 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7365 | |
b28ab83c | 7366 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7367 | |
b28ab83c PZ |
7368 | if (!--swhash->hlist_refcount) |
7369 | swevent_hlist_release(swhash); | |
76e1d904 | 7370 | |
b28ab83c | 7371 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7372 | } |
7373 | ||
3b364d7b | 7374 | static void swevent_hlist_put(void) |
76e1d904 FW |
7375 | { |
7376 | int cpu; | |
7377 | ||
76e1d904 | 7378 | for_each_possible_cpu(cpu) |
3b364d7b | 7379 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7380 | } |
7381 | ||
3b364d7b | 7382 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7383 | { |
b28ab83c | 7384 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7385 | int err = 0; |
7386 | ||
b28ab83c | 7387 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7388 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7389 | struct swevent_hlist *hlist; |
7390 | ||
7391 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7392 | if (!hlist) { | |
7393 | err = -ENOMEM; | |
7394 | goto exit; | |
7395 | } | |
b28ab83c | 7396 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7397 | } |
b28ab83c | 7398 | swhash->hlist_refcount++; |
9ed6060d | 7399 | exit: |
b28ab83c | 7400 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7401 | |
7402 | return err; | |
7403 | } | |
7404 | ||
3b364d7b | 7405 | static int swevent_hlist_get(void) |
76e1d904 | 7406 | { |
3b364d7b | 7407 | int err, cpu, failed_cpu; |
76e1d904 | 7408 | |
76e1d904 FW |
7409 | get_online_cpus(); |
7410 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7411 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7412 | if (err) { |
7413 | failed_cpu = cpu; | |
7414 | goto fail; | |
7415 | } | |
7416 | } | |
7417 | put_online_cpus(); | |
7418 | ||
7419 | return 0; | |
9ed6060d | 7420 | fail: |
76e1d904 FW |
7421 | for_each_possible_cpu(cpu) { |
7422 | if (cpu == failed_cpu) | |
7423 | break; | |
3b364d7b | 7424 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7425 | } |
7426 | ||
7427 | put_online_cpus(); | |
7428 | return err; | |
7429 | } | |
7430 | ||
c5905afb | 7431 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7432 | |
b0a873eb PZ |
7433 | static void sw_perf_event_destroy(struct perf_event *event) |
7434 | { | |
7435 | u64 event_id = event->attr.config; | |
95476b64 | 7436 | |
b0a873eb PZ |
7437 | WARN_ON(event->parent); |
7438 | ||
c5905afb | 7439 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7440 | swevent_hlist_put(); |
b0a873eb PZ |
7441 | } |
7442 | ||
7443 | static int perf_swevent_init(struct perf_event *event) | |
7444 | { | |
8176cced | 7445 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7446 | |
7447 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7448 | return -ENOENT; | |
7449 | ||
2481c5fa SE |
7450 | /* |
7451 | * no branch sampling for software events | |
7452 | */ | |
7453 | if (has_branch_stack(event)) | |
7454 | return -EOPNOTSUPP; | |
7455 | ||
b0a873eb PZ |
7456 | switch (event_id) { |
7457 | case PERF_COUNT_SW_CPU_CLOCK: | |
7458 | case PERF_COUNT_SW_TASK_CLOCK: | |
7459 | return -ENOENT; | |
7460 | ||
7461 | default: | |
7462 | break; | |
7463 | } | |
7464 | ||
ce677831 | 7465 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7466 | return -ENOENT; |
7467 | ||
7468 | if (!event->parent) { | |
7469 | int err; | |
7470 | ||
3b364d7b | 7471 | err = swevent_hlist_get(); |
b0a873eb PZ |
7472 | if (err) |
7473 | return err; | |
7474 | ||
c5905afb | 7475 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7476 | event->destroy = sw_perf_event_destroy; |
7477 | } | |
7478 | ||
7479 | return 0; | |
7480 | } | |
7481 | ||
7482 | static struct pmu perf_swevent = { | |
89a1e187 | 7483 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7484 | |
34f43927 PZ |
7485 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7486 | ||
b0a873eb | 7487 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7488 | .add = perf_swevent_add, |
7489 | .del = perf_swevent_del, | |
7490 | .start = perf_swevent_start, | |
7491 | .stop = perf_swevent_stop, | |
1c024eca | 7492 | .read = perf_swevent_read, |
1c024eca PZ |
7493 | }; |
7494 | ||
b0a873eb PZ |
7495 | #ifdef CONFIG_EVENT_TRACING |
7496 | ||
1c024eca PZ |
7497 | static int perf_tp_filter_match(struct perf_event *event, |
7498 | struct perf_sample_data *data) | |
7499 | { | |
7e3f977e | 7500 | void *record = data->raw->frag.data; |
1c024eca | 7501 | |
b71b437e PZ |
7502 | /* only top level events have filters set */ |
7503 | if (event->parent) | |
7504 | event = event->parent; | |
7505 | ||
1c024eca PZ |
7506 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7507 | return 1; | |
7508 | return 0; | |
7509 | } | |
7510 | ||
7511 | static int perf_tp_event_match(struct perf_event *event, | |
7512 | struct perf_sample_data *data, | |
7513 | struct pt_regs *regs) | |
7514 | { | |
a0f7d0f7 FW |
7515 | if (event->hw.state & PERF_HES_STOPPED) |
7516 | return 0; | |
580d607c PZ |
7517 | /* |
7518 | * All tracepoints are from kernel-space. | |
7519 | */ | |
7520 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7521 | return 0; |
7522 | ||
7523 | if (!perf_tp_filter_match(event, data)) | |
7524 | return 0; | |
7525 | ||
7526 | return 1; | |
7527 | } | |
7528 | ||
85b67bcb AS |
7529 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7530 | struct trace_event_call *call, u64 count, | |
7531 | struct pt_regs *regs, struct hlist_head *head, | |
7532 | struct task_struct *task) | |
7533 | { | |
7534 | struct bpf_prog *prog = call->prog; | |
7535 | ||
7536 | if (prog) { | |
7537 | *(struct pt_regs **)raw_data = regs; | |
7538 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7539 | perf_swevent_put_recursion_context(rctx); | |
7540 | return; | |
7541 | } | |
7542 | } | |
7543 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7544 | rctx, task); | |
7545 | } | |
7546 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7547 | ||
1e1dcd93 | 7548 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7549 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7550 | struct task_struct *task) | |
95476b64 FW |
7551 | { |
7552 | struct perf_sample_data data; | |
1c024eca | 7553 | struct perf_event *event; |
1c024eca | 7554 | |
95476b64 | 7555 | struct perf_raw_record raw = { |
7e3f977e DB |
7556 | .frag = { |
7557 | .size = entry_size, | |
7558 | .data = record, | |
7559 | }, | |
95476b64 FW |
7560 | }; |
7561 | ||
1e1dcd93 | 7562 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7563 | data.raw = &raw; |
7564 | ||
1e1dcd93 AS |
7565 | perf_trace_buf_update(record, event_type); |
7566 | ||
b67bfe0d | 7567 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7568 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7569 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7570 | } |
ecc55f84 | 7571 | |
e6dab5ff AV |
7572 | /* |
7573 | * If we got specified a target task, also iterate its context and | |
7574 | * deliver this event there too. | |
7575 | */ | |
7576 | if (task && task != current) { | |
7577 | struct perf_event_context *ctx; | |
7578 | struct trace_entry *entry = record; | |
7579 | ||
7580 | rcu_read_lock(); | |
7581 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7582 | if (!ctx) | |
7583 | goto unlock; | |
7584 | ||
7585 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7586 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7587 | continue; | |
7588 | if (event->attr.config != entry->type) | |
7589 | continue; | |
7590 | if (perf_tp_event_match(event, &data, regs)) | |
7591 | perf_swevent_event(event, count, &data, regs); | |
7592 | } | |
7593 | unlock: | |
7594 | rcu_read_unlock(); | |
7595 | } | |
7596 | ||
ecc55f84 | 7597 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7598 | } |
7599 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7600 | ||
cdd6c482 | 7601 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7602 | { |
1c024eca | 7603 | perf_trace_destroy(event); |
e077df4f PZ |
7604 | } |
7605 | ||
b0a873eb | 7606 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7607 | { |
76e1d904 FW |
7608 | int err; |
7609 | ||
b0a873eb PZ |
7610 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7611 | return -ENOENT; | |
7612 | ||
2481c5fa SE |
7613 | /* |
7614 | * no branch sampling for tracepoint events | |
7615 | */ | |
7616 | if (has_branch_stack(event)) | |
7617 | return -EOPNOTSUPP; | |
7618 | ||
1c024eca PZ |
7619 | err = perf_trace_init(event); |
7620 | if (err) | |
b0a873eb | 7621 | return err; |
e077df4f | 7622 | |
cdd6c482 | 7623 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7624 | |
b0a873eb PZ |
7625 | return 0; |
7626 | } | |
7627 | ||
7628 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7629 | .task_ctx_nr = perf_sw_context, |
7630 | ||
b0a873eb | 7631 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7632 | .add = perf_trace_add, |
7633 | .del = perf_trace_del, | |
7634 | .start = perf_swevent_start, | |
7635 | .stop = perf_swevent_stop, | |
b0a873eb | 7636 | .read = perf_swevent_read, |
b0a873eb PZ |
7637 | }; |
7638 | ||
7639 | static inline void perf_tp_register(void) | |
7640 | { | |
2e80a82a | 7641 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7642 | } |
6fb2915d | 7643 | |
6fb2915d LZ |
7644 | static void perf_event_free_filter(struct perf_event *event) |
7645 | { | |
7646 | ftrace_profile_free_filter(event); | |
7647 | } | |
7648 | ||
2541517c AS |
7649 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7650 | { | |
98b5c2c6 | 7651 | bool is_kprobe, is_tracepoint; |
2541517c AS |
7652 | struct bpf_prog *prog; |
7653 | ||
7654 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7655 | return -EINVAL; | |
7656 | ||
7657 | if (event->tp_event->prog) | |
7658 | return -EEXIST; | |
7659 | ||
98b5c2c6 AS |
7660 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
7661 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
7662 | if (!is_kprobe && !is_tracepoint) | |
7663 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
7664 | return -EINVAL; |
7665 | ||
7666 | prog = bpf_prog_get(prog_fd); | |
7667 | if (IS_ERR(prog)) | |
7668 | return PTR_ERR(prog); | |
7669 | ||
98b5c2c6 AS |
7670 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
7671 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
7672 | /* valid fd, but invalid bpf program type */ |
7673 | bpf_prog_put(prog); | |
7674 | return -EINVAL; | |
7675 | } | |
7676 | ||
32bbe007 AS |
7677 | if (is_tracepoint) { |
7678 | int off = trace_event_get_offsets(event->tp_event); | |
7679 | ||
7680 | if (prog->aux->max_ctx_offset > off) { | |
7681 | bpf_prog_put(prog); | |
7682 | return -EACCES; | |
7683 | } | |
7684 | } | |
2541517c AS |
7685 | event->tp_event->prog = prog; |
7686 | ||
7687 | return 0; | |
7688 | } | |
7689 | ||
7690 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7691 | { | |
7692 | struct bpf_prog *prog; | |
7693 | ||
7694 | if (!event->tp_event) | |
7695 | return; | |
7696 | ||
7697 | prog = event->tp_event->prog; | |
7698 | if (prog) { | |
7699 | event->tp_event->prog = NULL; | |
1aacde3d | 7700 | bpf_prog_put(prog); |
2541517c AS |
7701 | } |
7702 | } | |
7703 | ||
e077df4f | 7704 | #else |
6fb2915d | 7705 | |
b0a873eb | 7706 | static inline void perf_tp_register(void) |
e077df4f | 7707 | { |
e077df4f | 7708 | } |
6fb2915d | 7709 | |
6fb2915d LZ |
7710 | static void perf_event_free_filter(struct perf_event *event) |
7711 | { | |
7712 | } | |
7713 | ||
2541517c AS |
7714 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7715 | { | |
7716 | return -ENOENT; | |
7717 | } | |
7718 | ||
7719 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7720 | { | |
7721 | } | |
07b139c8 | 7722 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7723 | |
24f1e32c | 7724 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7725 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7726 | { |
f5ffe02e FW |
7727 | struct perf_sample_data sample; |
7728 | struct pt_regs *regs = data; | |
7729 | ||
fd0d000b | 7730 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7731 | |
a4eaf7f1 | 7732 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7733 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7734 | } |
7735 | #endif | |
7736 | ||
375637bc AS |
7737 | /* |
7738 | * Allocate a new address filter | |
7739 | */ | |
7740 | static struct perf_addr_filter * | |
7741 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
7742 | { | |
7743 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
7744 | struct perf_addr_filter *filter; | |
7745 | ||
7746 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
7747 | if (!filter) | |
7748 | return NULL; | |
7749 | ||
7750 | INIT_LIST_HEAD(&filter->entry); | |
7751 | list_add_tail(&filter->entry, filters); | |
7752 | ||
7753 | return filter; | |
7754 | } | |
7755 | ||
7756 | static void free_filters_list(struct list_head *filters) | |
7757 | { | |
7758 | struct perf_addr_filter *filter, *iter; | |
7759 | ||
7760 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
7761 | if (filter->inode) | |
7762 | iput(filter->inode); | |
7763 | list_del(&filter->entry); | |
7764 | kfree(filter); | |
7765 | } | |
7766 | } | |
7767 | ||
7768 | /* | |
7769 | * Free existing address filters and optionally install new ones | |
7770 | */ | |
7771 | static void perf_addr_filters_splice(struct perf_event *event, | |
7772 | struct list_head *head) | |
7773 | { | |
7774 | unsigned long flags; | |
7775 | LIST_HEAD(list); | |
7776 | ||
7777 | if (!has_addr_filter(event)) | |
7778 | return; | |
7779 | ||
7780 | /* don't bother with children, they don't have their own filters */ | |
7781 | if (event->parent) | |
7782 | return; | |
7783 | ||
7784 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
7785 | ||
7786 | list_splice_init(&event->addr_filters.list, &list); | |
7787 | if (head) | |
7788 | list_splice(head, &event->addr_filters.list); | |
7789 | ||
7790 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
7791 | ||
7792 | free_filters_list(&list); | |
7793 | } | |
7794 | ||
7795 | /* | |
7796 | * Scan through mm's vmas and see if one of them matches the | |
7797 | * @filter; if so, adjust filter's address range. | |
7798 | * Called with mm::mmap_sem down for reading. | |
7799 | */ | |
7800 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
7801 | struct mm_struct *mm) | |
7802 | { | |
7803 | struct vm_area_struct *vma; | |
7804 | ||
7805 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
7806 | struct file *file = vma->vm_file; | |
7807 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7808 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7809 | ||
7810 | if (!file) | |
7811 | continue; | |
7812 | ||
7813 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7814 | continue; | |
7815 | ||
7816 | return vma->vm_start; | |
7817 | } | |
7818 | ||
7819 | return 0; | |
7820 | } | |
7821 | ||
7822 | /* | |
7823 | * Update event's address range filters based on the | |
7824 | * task's existing mappings, if any. | |
7825 | */ | |
7826 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
7827 | { | |
7828 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7829 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
7830 | struct perf_addr_filter *filter; | |
7831 | struct mm_struct *mm = NULL; | |
7832 | unsigned int count = 0; | |
7833 | unsigned long flags; | |
7834 | ||
7835 | /* | |
7836 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
7837 | * will stop on the parent's child_mutex that our caller is also holding | |
7838 | */ | |
7839 | if (task == TASK_TOMBSTONE) | |
7840 | return; | |
7841 | ||
7842 | mm = get_task_mm(event->ctx->task); | |
7843 | if (!mm) | |
7844 | goto restart; | |
7845 | ||
7846 | down_read(&mm->mmap_sem); | |
7847 | ||
7848 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7849 | list_for_each_entry(filter, &ifh->list, entry) { | |
7850 | event->addr_filters_offs[count] = 0; | |
7851 | ||
99f5bc9b MP |
7852 | /* |
7853 | * Adjust base offset if the filter is associated to a binary | |
7854 | * that needs to be mapped: | |
7855 | */ | |
7856 | if (filter->inode) | |
375637bc AS |
7857 | event->addr_filters_offs[count] = |
7858 | perf_addr_filter_apply(filter, mm); | |
7859 | ||
7860 | count++; | |
7861 | } | |
7862 | ||
7863 | event->addr_filters_gen++; | |
7864 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7865 | ||
7866 | up_read(&mm->mmap_sem); | |
7867 | ||
7868 | mmput(mm); | |
7869 | ||
7870 | restart: | |
7871 | perf_event_restart(event); | |
7872 | } | |
7873 | ||
7874 | /* | |
7875 | * Address range filtering: limiting the data to certain | |
7876 | * instruction address ranges. Filters are ioctl()ed to us from | |
7877 | * userspace as ascii strings. | |
7878 | * | |
7879 | * Filter string format: | |
7880 | * | |
7881 | * ACTION RANGE_SPEC | |
7882 | * where ACTION is one of the | |
7883 | * * "filter": limit the trace to this region | |
7884 | * * "start": start tracing from this address | |
7885 | * * "stop": stop tracing at this address/region; | |
7886 | * RANGE_SPEC is | |
7887 | * * for kernel addresses: <start address>[/<size>] | |
7888 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
7889 | * | |
7890 | * if <size> is not specified, the range is treated as a single address. | |
7891 | */ | |
7892 | enum { | |
7893 | IF_ACT_FILTER, | |
7894 | IF_ACT_START, | |
7895 | IF_ACT_STOP, | |
7896 | IF_SRC_FILE, | |
7897 | IF_SRC_KERNEL, | |
7898 | IF_SRC_FILEADDR, | |
7899 | IF_SRC_KERNELADDR, | |
7900 | }; | |
7901 | ||
7902 | enum { | |
7903 | IF_STATE_ACTION = 0, | |
7904 | IF_STATE_SOURCE, | |
7905 | IF_STATE_END, | |
7906 | }; | |
7907 | ||
7908 | static const match_table_t if_tokens = { | |
7909 | { IF_ACT_FILTER, "filter" }, | |
7910 | { IF_ACT_START, "start" }, | |
7911 | { IF_ACT_STOP, "stop" }, | |
7912 | { IF_SRC_FILE, "%u/%u@%s" }, | |
7913 | { IF_SRC_KERNEL, "%u/%u" }, | |
7914 | { IF_SRC_FILEADDR, "%u@%s" }, | |
7915 | { IF_SRC_KERNELADDR, "%u" }, | |
7916 | }; | |
7917 | ||
7918 | /* | |
7919 | * Address filter string parser | |
7920 | */ | |
7921 | static int | |
7922 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
7923 | struct list_head *filters) | |
7924 | { | |
7925 | struct perf_addr_filter *filter = NULL; | |
7926 | char *start, *orig, *filename = NULL; | |
7927 | struct path path; | |
7928 | substring_t args[MAX_OPT_ARGS]; | |
7929 | int state = IF_STATE_ACTION, token; | |
7930 | unsigned int kernel = 0; | |
7931 | int ret = -EINVAL; | |
7932 | ||
7933 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
7934 | if (!fstr) | |
7935 | return -ENOMEM; | |
7936 | ||
7937 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
7938 | ret = -EINVAL; | |
7939 | ||
7940 | if (!*start) | |
7941 | continue; | |
7942 | ||
7943 | /* filter definition begins */ | |
7944 | if (state == IF_STATE_ACTION) { | |
7945 | filter = perf_addr_filter_new(event, filters); | |
7946 | if (!filter) | |
7947 | goto fail; | |
7948 | } | |
7949 | ||
7950 | token = match_token(start, if_tokens, args); | |
7951 | switch (token) { | |
7952 | case IF_ACT_FILTER: | |
7953 | case IF_ACT_START: | |
7954 | filter->filter = 1; | |
7955 | ||
7956 | case IF_ACT_STOP: | |
7957 | if (state != IF_STATE_ACTION) | |
7958 | goto fail; | |
7959 | ||
7960 | state = IF_STATE_SOURCE; | |
7961 | break; | |
7962 | ||
7963 | case IF_SRC_KERNELADDR: | |
7964 | case IF_SRC_KERNEL: | |
7965 | kernel = 1; | |
7966 | ||
7967 | case IF_SRC_FILEADDR: | |
7968 | case IF_SRC_FILE: | |
7969 | if (state != IF_STATE_SOURCE) | |
7970 | goto fail; | |
7971 | ||
7972 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
7973 | filter->range = 1; | |
7974 | ||
7975 | *args[0].to = 0; | |
7976 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
7977 | if (ret) | |
7978 | goto fail; | |
7979 | ||
7980 | if (filter->range) { | |
7981 | *args[1].to = 0; | |
7982 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
7983 | if (ret) | |
7984 | goto fail; | |
7985 | } | |
7986 | ||
4059ffd0 MP |
7987 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
7988 | int fpos = filter->range ? 2 : 1; | |
7989 | ||
7990 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
7991 | if (!filename) { |
7992 | ret = -ENOMEM; | |
7993 | goto fail; | |
7994 | } | |
7995 | } | |
7996 | ||
7997 | state = IF_STATE_END; | |
7998 | break; | |
7999 | ||
8000 | default: | |
8001 | goto fail; | |
8002 | } | |
8003 | ||
8004 | /* | |
8005 | * Filter definition is fully parsed, validate and install it. | |
8006 | * Make sure that it doesn't contradict itself or the event's | |
8007 | * attribute. | |
8008 | */ | |
8009 | if (state == IF_STATE_END) { | |
8010 | if (kernel && event->attr.exclude_kernel) | |
8011 | goto fail; | |
8012 | ||
8013 | if (!kernel) { | |
8014 | if (!filename) | |
8015 | goto fail; | |
8016 | ||
8017 | /* look up the path and grab its inode */ | |
8018 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8019 | if (ret) | |
8020 | goto fail_free_name; | |
8021 | ||
8022 | filter->inode = igrab(d_inode(path.dentry)); | |
8023 | path_put(&path); | |
8024 | kfree(filename); | |
8025 | filename = NULL; | |
8026 | ||
8027 | ret = -EINVAL; | |
8028 | if (!filter->inode || | |
8029 | !S_ISREG(filter->inode->i_mode)) | |
8030 | /* free_filters_list() will iput() */ | |
8031 | goto fail; | |
8032 | } | |
8033 | ||
8034 | /* ready to consume more filters */ | |
8035 | state = IF_STATE_ACTION; | |
8036 | filter = NULL; | |
8037 | } | |
8038 | } | |
8039 | ||
8040 | if (state != IF_STATE_ACTION) | |
8041 | goto fail; | |
8042 | ||
8043 | kfree(orig); | |
8044 | ||
8045 | return 0; | |
8046 | ||
8047 | fail_free_name: | |
8048 | kfree(filename); | |
8049 | fail: | |
8050 | free_filters_list(filters); | |
8051 | kfree(orig); | |
8052 | ||
8053 | return ret; | |
8054 | } | |
8055 | ||
8056 | static int | |
8057 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8058 | { | |
8059 | LIST_HEAD(filters); | |
8060 | int ret; | |
8061 | ||
8062 | /* | |
8063 | * Since this is called in perf_ioctl() path, we're already holding | |
8064 | * ctx::mutex. | |
8065 | */ | |
8066 | lockdep_assert_held(&event->ctx->mutex); | |
8067 | ||
8068 | if (WARN_ON_ONCE(event->parent)) | |
8069 | return -EINVAL; | |
8070 | ||
8071 | /* | |
8072 | * For now, we only support filtering in per-task events; doing so | |
8073 | * for CPU-wide events requires additional context switching trickery, | |
8074 | * since same object code will be mapped at different virtual | |
8075 | * addresses in different processes. | |
8076 | */ | |
8077 | if (!event->ctx->task) | |
8078 | return -EOPNOTSUPP; | |
8079 | ||
8080 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); | |
8081 | if (ret) | |
8082 | return ret; | |
8083 | ||
8084 | ret = event->pmu->addr_filters_validate(&filters); | |
8085 | if (ret) { | |
8086 | free_filters_list(&filters); | |
8087 | return ret; | |
8088 | } | |
8089 | ||
8090 | /* remove existing filters, if any */ | |
8091 | perf_addr_filters_splice(event, &filters); | |
8092 | ||
8093 | /* install new filters */ | |
8094 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8095 | ||
8096 | return ret; | |
8097 | } | |
8098 | ||
c796bbbe AS |
8099 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8100 | { | |
8101 | char *filter_str; | |
8102 | int ret = -EINVAL; | |
8103 | ||
375637bc AS |
8104 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8105 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8106 | !has_addr_filter(event)) | |
c796bbbe AS |
8107 | return -EINVAL; |
8108 | ||
8109 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8110 | if (IS_ERR(filter_str)) | |
8111 | return PTR_ERR(filter_str); | |
8112 | ||
8113 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8114 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8115 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8116 | filter_str); | |
375637bc AS |
8117 | else if (has_addr_filter(event)) |
8118 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8119 | |
8120 | kfree(filter_str); | |
8121 | return ret; | |
8122 | } | |
8123 | ||
b0a873eb PZ |
8124 | /* |
8125 | * hrtimer based swevent callback | |
8126 | */ | |
f29ac756 | 8127 | |
b0a873eb | 8128 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8129 | { |
b0a873eb PZ |
8130 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8131 | struct perf_sample_data data; | |
8132 | struct pt_regs *regs; | |
8133 | struct perf_event *event; | |
8134 | u64 period; | |
f29ac756 | 8135 | |
b0a873eb | 8136 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8137 | |
8138 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8139 | return HRTIMER_NORESTART; | |
8140 | ||
b0a873eb | 8141 | event->pmu->read(event); |
f344011c | 8142 | |
fd0d000b | 8143 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8144 | regs = get_irq_regs(); |
8145 | ||
8146 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8147 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8148 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8149 | ret = HRTIMER_NORESTART; |
8150 | } | |
24f1e32c | 8151 | |
b0a873eb PZ |
8152 | period = max_t(u64, 10000, event->hw.sample_period); |
8153 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8154 | |
b0a873eb | 8155 | return ret; |
f29ac756 PZ |
8156 | } |
8157 | ||
b0a873eb | 8158 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8159 | { |
b0a873eb | 8160 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8161 | s64 period; |
8162 | ||
8163 | if (!is_sampling_event(event)) | |
8164 | return; | |
f5ffe02e | 8165 | |
5d508e82 FBH |
8166 | period = local64_read(&hwc->period_left); |
8167 | if (period) { | |
8168 | if (period < 0) | |
8169 | period = 10000; | |
fa407f35 | 8170 | |
5d508e82 FBH |
8171 | local64_set(&hwc->period_left, 0); |
8172 | } else { | |
8173 | period = max_t(u64, 10000, hwc->sample_period); | |
8174 | } | |
3497d206 TG |
8175 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8176 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8177 | } |
b0a873eb PZ |
8178 | |
8179 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8180 | { |
b0a873eb PZ |
8181 | struct hw_perf_event *hwc = &event->hw; |
8182 | ||
6c7e550f | 8183 | if (is_sampling_event(event)) { |
b0a873eb | 8184 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8185 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8186 | |
8187 | hrtimer_cancel(&hwc->hrtimer); | |
8188 | } | |
24f1e32c FW |
8189 | } |
8190 | ||
ba3dd36c PZ |
8191 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8192 | { | |
8193 | struct hw_perf_event *hwc = &event->hw; | |
8194 | ||
8195 | if (!is_sampling_event(event)) | |
8196 | return; | |
8197 | ||
8198 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8199 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8200 | ||
8201 | /* | |
8202 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8203 | * mapping and avoid the whole period adjust feedback stuff. | |
8204 | */ | |
8205 | if (event->attr.freq) { | |
8206 | long freq = event->attr.sample_freq; | |
8207 | ||
8208 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8209 | hwc->sample_period = event->attr.sample_period; | |
8210 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8211 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8212 | event->attr.freq = 0; |
8213 | } | |
8214 | } | |
8215 | ||
b0a873eb PZ |
8216 | /* |
8217 | * Software event: cpu wall time clock | |
8218 | */ | |
8219 | ||
8220 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8221 | { |
b0a873eb PZ |
8222 | s64 prev; |
8223 | u64 now; | |
8224 | ||
a4eaf7f1 | 8225 | now = local_clock(); |
b0a873eb PZ |
8226 | prev = local64_xchg(&event->hw.prev_count, now); |
8227 | local64_add(now - prev, &event->count); | |
24f1e32c | 8228 | } |
24f1e32c | 8229 | |
a4eaf7f1 | 8230 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8231 | { |
a4eaf7f1 | 8232 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8233 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8234 | } |
8235 | ||
a4eaf7f1 | 8236 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8237 | { |
b0a873eb PZ |
8238 | perf_swevent_cancel_hrtimer(event); |
8239 | cpu_clock_event_update(event); | |
8240 | } | |
f29ac756 | 8241 | |
a4eaf7f1 PZ |
8242 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8243 | { | |
8244 | if (flags & PERF_EF_START) | |
8245 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8246 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8247 | |
8248 | return 0; | |
8249 | } | |
8250 | ||
8251 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8252 | { | |
8253 | cpu_clock_event_stop(event, flags); | |
8254 | } | |
8255 | ||
b0a873eb PZ |
8256 | static void cpu_clock_event_read(struct perf_event *event) |
8257 | { | |
8258 | cpu_clock_event_update(event); | |
8259 | } | |
f344011c | 8260 | |
b0a873eb PZ |
8261 | static int cpu_clock_event_init(struct perf_event *event) |
8262 | { | |
8263 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8264 | return -ENOENT; | |
8265 | ||
8266 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8267 | return -ENOENT; | |
8268 | ||
2481c5fa SE |
8269 | /* |
8270 | * no branch sampling for software events | |
8271 | */ | |
8272 | if (has_branch_stack(event)) | |
8273 | return -EOPNOTSUPP; | |
8274 | ||
ba3dd36c PZ |
8275 | perf_swevent_init_hrtimer(event); |
8276 | ||
b0a873eb | 8277 | return 0; |
f29ac756 PZ |
8278 | } |
8279 | ||
b0a873eb | 8280 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8281 | .task_ctx_nr = perf_sw_context, |
8282 | ||
34f43927 PZ |
8283 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8284 | ||
b0a873eb | 8285 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8286 | .add = cpu_clock_event_add, |
8287 | .del = cpu_clock_event_del, | |
8288 | .start = cpu_clock_event_start, | |
8289 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8290 | .read = cpu_clock_event_read, |
8291 | }; | |
8292 | ||
8293 | /* | |
8294 | * Software event: task time clock | |
8295 | */ | |
8296 | ||
8297 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8298 | { |
b0a873eb PZ |
8299 | u64 prev; |
8300 | s64 delta; | |
5c92d124 | 8301 | |
b0a873eb PZ |
8302 | prev = local64_xchg(&event->hw.prev_count, now); |
8303 | delta = now - prev; | |
8304 | local64_add(delta, &event->count); | |
8305 | } | |
5c92d124 | 8306 | |
a4eaf7f1 | 8307 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8308 | { |
a4eaf7f1 | 8309 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8310 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8311 | } |
8312 | ||
a4eaf7f1 | 8313 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8314 | { |
8315 | perf_swevent_cancel_hrtimer(event); | |
8316 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8317 | } |
8318 | ||
8319 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8320 | { | |
8321 | if (flags & PERF_EF_START) | |
8322 | task_clock_event_start(event, flags); | |
6a694a60 | 8323 | perf_event_update_userpage(event); |
b0a873eb | 8324 | |
a4eaf7f1 PZ |
8325 | return 0; |
8326 | } | |
8327 | ||
8328 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8329 | { | |
8330 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8331 | } |
8332 | ||
8333 | static void task_clock_event_read(struct perf_event *event) | |
8334 | { | |
768a06e2 PZ |
8335 | u64 now = perf_clock(); |
8336 | u64 delta = now - event->ctx->timestamp; | |
8337 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8338 | |
8339 | task_clock_event_update(event, time); | |
8340 | } | |
8341 | ||
8342 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8343 | { |
b0a873eb PZ |
8344 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8345 | return -ENOENT; | |
8346 | ||
8347 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8348 | return -ENOENT; | |
8349 | ||
2481c5fa SE |
8350 | /* |
8351 | * no branch sampling for software events | |
8352 | */ | |
8353 | if (has_branch_stack(event)) | |
8354 | return -EOPNOTSUPP; | |
8355 | ||
ba3dd36c PZ |
8356 | perf_swevent_init_hrtimer(event); |
8357 | ||
b0a873eb | 8358 | return 0; |
6fb2915d LZ |
8359 | } |
8360 | ||
b0a873eb | 8361 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8362 | .task_ctx_nr = perf_sw_context, |
8363 | ||
34f43927 PZ |
8364 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8365 | ||
b0a873eb | 8366 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8367 | .add = task_clock_event_add, |
8368 | .del = task_clock_event_del, | |
8369 | .start = task_clock_event_start, | |
8370 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8371 | .read = task_clock_event_read, |
8372 | }; | |
6fb2915d | 8373 | |
ad5133b7 | 8374 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8375 | { |
e077df4f | 8376 | } |
6fb2915d | 8377 | |
fbbe0701 SB |
8378 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8379 | { | |
8380 | } | |
8381 | ||
ad5133b7 | 8382 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8383 | { |
ad5133b7 | 8384 | return 0; |
6fb2915d LZ |
8385 | } |
8386 | ||
18ab2cd3 | 8387 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8388 | |
8389 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8390 | { |
fbbe0701 SB |
8391 | __this_cpu_write(nop_txn_flags, flags); |
8392 | ||
8393 | if (flags & ~PERF_PMU_TXN_ADD) | |
8394 | return; | |
8395 | ||
ad5133b7 | 8396 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8397 | } |
8398 | ||
ad5133b7 PZ |
8399 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8400 | { | |
fbbe0701 SB |
8401 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8402 | ||
8403 | __this_cpu_write(nop_txn_flags, 0); | |
8404 | ||
8405 | if (flags & ~PERF_PMU_TXN_ADD) | |
8406 | return 0; | |
8407 | ||
ad5133b7 PZ |
8408 | perf_pmu_enable(pmu); |
8409 | return 0; | |
8410 | } | |
e077df4f | 8411 | |
ad5133b7 | 8412 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8413 | { |
fbbe0701 SB |
8414 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8415 | ||
8416 | __this_cpu_write(nop_txn_flags, 0); | |
8417 | ||
8418 | if (flags & ~PERF_PMU_TXN_ADD) | |
8419 | return; | |
8420 | ||
ad5133b7 | 8421 | perf_pmu_enable(pmu); |
24f1e32c FW |
8422 | } |
8423 | ||
35edc2a5 PZ |
8424 | static int perf_event_idx_default(struct perf_event *event) |
8425 | { | |
c719f560 | 8426 | return 0; |
35edc2a5 PZ |
8427 | } |
8428 | ||
8dc85d54 PZ |
8429 | /* |
8430 | * Ensures all contexts with the same task_ctx_nr have the same | |
8431 | * pmu_cpu_context too. | |
8432 | */ | |
9e317041 | 8433 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8434 | { |
8dc85d54 | 8435 | struct pmu *pmu; |
b326e956 | 8436 | |
8dc85d54 PZ |
8437 | if (ctxn < 0) |
8438 | return NULL; | |
24f1e32c | 8439 | |
8dc85d54 PZ |
8440 | list_for_each_entry(pmu, &pmus, entry) { |
8441 | if (pmu->task_ctx_nr == ctxn) | |
8442 | return pmu->pmu_cpu_context; | |
8443 | } | |
24f1e32c | 8444 | |
8dc85d54 | 8445 | return NULL; |
24f1e32c FW |
8446 | } |
8447 | ||
51676957 | 8448 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 8449 | { |
51676957 PZ |
8450 | int cpu; |
8451 | ||
8452 | for_each_possible_cpu(cpu) { | |
8453 | struct perf_cpu_context *cpuctx; | |
8454 | ||
8455 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8456 | ||
3f1f3320 PZ |
8457 | if (cpuctx->unique_pmu == old_pmu) |
8458 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
8459 | } |
8460 | } | |
8461 | ||
8462 | static void free_pmu_context(struct pmu *pmu) | |
8463 | { | |
8464 | struct pmu *i; | |
f5ffe02e | 8465 | |
8dc85d54 | 8466 | mutex_lock(&pmus_lock); |
0475f9ea | 8467 | /* |
8dc85d54 | 8468 | * Like a real lame refcount. |
0475f9ea | 8469 | */ |
51676957 PZ |
8470 | list_for_each_entry(i, &pmus, entry) { |
8471 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
8472 | update_pmu_context(i, pmu); | |
8dc85d54 | 8473 | goto out; |
51676957 | 8474 | } |
8dc85d54 | 8475 | } |
d6d020e9 | 8476 | |
51676957 | 8477 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
8478 | out: |
8479 | mutex_unlock(&pmus_lock); | |
24f1e32c | 8480 | } |
6e855cd4 AS |
8481 | |
8482 | /* | |
8483 | * Let userspace know that this PMU supports address range filtering: | |
8484 | */ | |
8485 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8486 | struct device_attribute *attr, | |
8487 | char *page) | |
8488 | { | |
8489 | struct pmu *pmu = dev_get_drvdata(dev); | |
8490 | ||
8491 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8492 | } | |
8493 | DEVICE_ATTR_RO(nr_addr_filters); | |
8494 | ||
2e80a82a | 8495 | static struct idr pmu_idr; |
d6d020e9 | 8496 | |
abe43400 PZ |
8497 | static ssize_t |
8498 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8499 | { | |
8500 | struct pmu *pmu = dev_get_drvdata(dev); | |
8501 | ||
8502 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8503 | } | |
90826ca7 | 8504 | static DEVICE_ATTR_RO(type); |
abe43400 | 8505 | |
62b85639 SE |
8506 | static ssize_t |
8507 | perf_event_mux_interval_ms_show(struct device *dev, | |
8508 | struct device_attribute *attr, | |
8509 | char *page) | |
8510 | { | |
8511 | struct pmu *pmu = dev_get_drvdata(dev); | |
8512 | ||
8513 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8514 | } | |
8515 | ||
272325c4 PZ |
8516 | static DEFINE_MUTEX(mux_interval_mutex); |
8517 | ||
62b85639 SE |
8518 | static ssize_t |
8519 | perf_event_mux_interval_ms_store(struct device *dev, | |
8520 | struct device_attribute *attr, | |
8521 | const char *buf, size_t count) | |
8522 | { | |
8523 | struct pmu *pmu = dev_get_drvdata(dev); | |
8524 | int timer, cpu, ret; | |
8525 | ||
8526 | ret = kstrtoint(buf, 0, &timer); | |
8527 | if (ret) | |
8528 | return ret; | |
8529 | ||
8530 | if (timer < 1) | |
8531 | return -EINVAL; | |
8532 | ||
8533 | /* same value, noting to do */ | |
8534 | if (timer == pmu->hrtimer_interval_ms) | |
8535 | return count; | |
8536 | ||
272325c4 | 8537 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8538 | pmu->hrtimer_interval_ms = timer; |
8539 | ||
8540 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8541 | get_online_cpus(); |
8542 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8543 | struct perf_cpu_context *cpuctx; |
8544 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8545 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8546 | ||
272325c4 PZ |
8547 | cpu_function_call(cpu, |
8548 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8549 | } |
272325c4 PZ |
8550 | put_online_cpus(); |
8551 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8552 | |
8553 | return count; | |
8554 | } | |
90826ca7 | 8555 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8556 | |
90826ca7 GKH |
8557 | static struct attribute *pmu_dev_attrs[] = { |
8558 | &dev_attr_type.attr, | |
8559 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8560 | NULL, | |
abe43400 | 8561 | }; |
90826ca7 | 8562 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8563 | |
8564 | static int pmu_bus_running; | |
8565 | static struct bus_type pmu_bus = { | |
8566 | .name = "event_source", | |
90826ca7 | 8567 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8568 | }; |
8569 | ||
8570 | static void pmu_dev_release(struct device *dev) | |
8571 | { | |
8572 | kfree(dev); | |
8573 | } | |
8574 | ||
8575 | static int pmu_dev_alloc(struct pmu *pmu) | |
8576 | { | |
8577 | int ret = -ENOMEM; | |
8578 | ||
8579 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8580 | if (!pmu->dev) | |
8581 | goto out; | |
8582 | ||
0c9d42ed | 8583 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8584 | device_initialize(pmu->dev); |
8585 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8586 | if (ret) | |
8587 | goto free_dev; | |
8588 | ||
8589 | dev_set_drvdata(pmu->dev, pmu); | |
8590 | pmu->dev->bus = &pmu_bus; | |
8591 | pmu->dev->release = pmu_dev_release; | |
8592 | ret = device_add(pmu->dev); | |
8593 | if (ret) | |
8594 | goto free_dev; | |
8595 | ||
6e855cd4 AS |
8596 | /* For PMUs with address filters, throw in an extra attribute: */ |
8597 | if (pmu->nr_addr_filters) | |
8598 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8599 | ||
8600 | if (ret) | |
8601 | goto del_dev; | |
8602 | ||
abe43400 PZ |
8603 | out: |
8604 | return ret; | |
8605 | ||
6e855cd4 AS |
8606 | del_dev: |
8607 | device_del(pmu->dev); | |
8608 | ||
abe43400 PZ |
8609 | free_dev: |
8610 | put_device(pmu->dev); | |
8611 | goto out; | |
8612 | } | |
8613 | ||
547e9fd7 | 8614 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8615 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8616 | |
03d8e80b | 8617 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 8618 | { |
108b02cf | 8619 | int cpu, ret; |
24f1e32c | 8620 | |
b0a873eb | 8621 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
8622 | ret = -ENOMEM; |
8623 | pmu->pmu_disable_count = alloc_percpu(int); | |
8624 | if (!pmu->pmu_disable_count) | |
8625 | goto unlock; | |
f29ac756 | 8626 | |
2e80a82a PZ |
8627 | pmu->type = -1; |
8628 | if (!name) | |
8629 | goto skip_type; | |
8630 | pmu->name = name; | |
8631 | ||
8632 | if (type < 0) { | |
0e9c3be2 TH |
8633 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
8634 | if (type < 0) { | |
8635 | ret = type; | |
2e80a82a PZ |
8636 | goto free_pdc; |
8637 | } | |
8638 | } | |
8639 | pmu->type = type; | |
8640 | ||
abe43400 PZ |
8641 | if (pmu_bus_running) { |
8642 | ret = pmu_dev_alloc(pmu); | |
8643 | if (ret) | |
8644 | goto free_idr; | |
8645 | } | |
8646 | ||
2e80a82a | 8647 | skip_type: |
26657848 PZ |
8648 | if (pmu->task_ctx_nr == perf_hw_context) { |
8649 | static int hw_context_taken = 0; | |
8650 | ||
5101ef20 MR |
8651 | /* |
8652 | * Other than systems with heterogeneous CPUs, it never makes | |
8653 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
8654 | * uncore must use perf_invalid_context. | |
8655 | */ | |
8656 | if (WARN_ON_ONCE(hw_context_taken && | |
8657 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
8658 | pmu->task_ctx_nr = perf_invalid_context; |
8659 | ||
8660 | hw_context_taken = 1; | |
8661 | } | |
8662 | ||
8dc85d54 PZ |
8663 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
8664 | if (pmu->pmu_cpu_context) | |
8665 | goto got_cpu_context; | |
f29ac756 | 8666 | |
c4814202 | 8667 | ret = -ENOMEM; |
108b02cf PZ |
8668 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
8669 | if (!pmu->pmu_cpu_context) | |
abe43400 | 8670 | goto free_dev; |
f344011c | 8671 | |
108b02cf PZ |
8672 | for_each_possible_cpu(cpu) { |
8673 | struct perf_cpu_context *cpuctx; | |
8674 | ||
8675 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 8676 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 8677 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 8678 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 8679 | cpuctx->ctx.pmu = pmu; |
9e630205 | 8680 | |
272325c4 | 8681 | __perf_mux_hrtimer_init(cpuctx, cpu); |
9e630205 | 8682 | |
3f1f3320 | 8683 | cpuctx->unique_pmu = pmu; |
108b02cf | 8684 | } |
76e1d904 | 8685 | |
8dc85d54 | 8686 | got_cpu_context: |
ad5133b7 PZ |
8687 | if (!pmu->start_txn) { |
8688 | if (pmu->pmu_enable) { | |
8689 | /* | |
8690 | * If we have pmu_enable/pmu_disable calls, install | |
8691 | * transaction stubs that use that to try and batch | |
8692 | * hardware accesses. | |
8693 | */ | |
8694 | pmu->start_txn = perf_pmu_start_txn; | |
8695 | pmu->commit_txn = perf_pmu_commit_txn; | |
8696 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
8697 | } else { | |
fbbe0701 | 8698 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
8699 | pmu->commit_txn = perf_pmu_nop_int; |
8700 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 8701 | } |
5c92d124 | 8702 | } |
15dbf27c | 8703 | |
ad5133b7 PZ |
8704 | if (!pmu->pmu_enable) { |
8705 | pmu->pmu_enable = perf_pmu_nop_void; | |
8706 | pmu->pmu_disable = perf_pmu_nop_void; | |
8707 | } | |
8708 | ||
35edc2a5 PZ |
8709 | if (!pmu->event_idx) |
8710 | pmu->event_idx = perf_event_idx_default; | |
8711 | ||
b0a873eb | 8712 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 8713 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
8714 | ret = 0; |
8715 | unlock: | |
b0a873eb PZ |
8716 | mutex_unlock(&pmus_lock); |
8717 | ||
33696fc0 | 8718 | return ret; |
108b02cf | 8719 | |
abe43400 PZ |
8720 | free_dev: |
8721 | device_del(pmu->dev); | |
8722 | put_device(pmu->dev); | |
8723 | ||
2e80a82a PZ |
8724 | free_idr: |
8725 | if (pmu->type >= PERF_TYPE_MAX) | |
8726 | idr_remove(&pmu_idr, pmu->type); | |
8727 | ||
108b02cf PZ |
8728 | free_pdc: |
8729 | free_percpu(pmu->pmu_disable_count); | |
8730 | goto unlock; | |
f29ac756 | 8731 | } |
c464c76e | 8732 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 8733 | |
b0a873eb | 8734 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 8735 | { |
b0a873eb PZ |
8736 | mutex_lock(&pmus_lock); |
8737 | list_del_rcu(&pmu->entry); | |
8738 | mutex_unlock(&pmus_lock); | |
5c92d124 | 8739 | |
0475f9ea | 8740 | /* |
cde8e884 PZ |
8741 | * We dereference the pmu list under both SRCU and regular RCU, so |
8742 | * synchronize against both of those. | |
0475f9ea | 8743 | */ |
b0a873eb | 8744 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 8745 | synchronize_rcu(); |
d6d020e9 | 8746 | |
33696fc0 | 8747 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
8748 | if (pmu->type >= PERF_TYPE_MAX) |
8749 | idr_remove(&pmu_idr, pmu->type); | |
6e855cd4 AS |
8750 | if (pmu->nr_addr_filters) |
8751 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
abe43400 PZ |
8752 | device_del(pmu->dev); |
8753 | put_device(pmu->dev); | |
51676957 | 8754 | free_pmu_context(pmu); |
b0a873eb | 8755 | } |
c464c76e | 8756 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 8757 | |
cc34b98b MR |
8758 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
8759 | { | |
ccd41c86 | 8760 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
8761 | int ret; |
8762 | ||
8763 | if (!try_module_get(pmu->module)) | |
8764 | return -ENODEV; | |
ccd41c86 PZ |
8765 | |
8766 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
8767 | /* |
8768 | * This ctx->mutex can nest when we're called through | |
8769 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
8770 | */ | |
8771 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
8772 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
8773 | BUG_ON(!ctx); |
8774 | } | |
8775 | ||
cc34b98b MR |
8776 | event->pmu = pmu; |
8777 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
8778 | |
8779 | if (ctx) | |
8780 | perf_event_ctx_unlock(event->group_leader, ctx); | |
8781 | ||
cc34b98b MR |
8782 | if (ret) |
8783 | module_put(pmu->module); | |
8784 | ||
8785 | return ret; | |
8786 | } | |
8787 | ||
18ab2cd3 | 8788 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
8789 | { |
8790 | struct pmu *pmu = NULL; | |
8791 | int idx; | |
940c5b29 | 8792 | int ret; |
b0a873eb PZ |
8793 | |
8794 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
8795 | |
8796 | rcu_read_lock(); | |
8797 | pmu = idr_find(&pmu_idr, event->attr.type); | |
8798 | rcu_read_unlock(); | |
940c5b29 | 8799 | if (pmu) { |
cc34b98b | 8800 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
8801 | if (ret) |
8802 | pmu = ERR_PTR(ret); | |
2e80a82a | 8803 | goto unlock; |
940c5b29 | 8804 | } |
2e80a82a | 8805 | |
b0a873eb | 8806 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 8807 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 8808 | if (!ret) |
e5f4d339 | 8809 | goto unlock; |
76e1d904 | 8810 | |
b0a873eb PZ |
8811 | if (ret != -ENOENT) { |
8812 | pmu = ERR_PTR(ret); | |
e5f4d339 | 8813 | goto unlock; |
f344011c | 8814 | } |
5c92d124 | 8815 | } |
e5f4d339 PZ |
8816 | pmu = ERR_PTR(-ENOENT); |
8817 | unlock: | |
b0a873eb | 8818 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 8819 | |
4aeb0b42 | 8820 | return pmu; |
5c92d124 IM |
8821 | } |
8822 | ||
f2fb6bef KL |
8823 | static void attach_sb_event(struct perf_event *event) |
8824 | { | |
8825 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
8826 | ||
8827 | raw_spin_lock(&pel->lock); | |
8828 | list_add_rcu(&event->sb_list, &pel->list); | |
8829 | raw_spin_unlock(&pel->lock); | |
8830 | } | |
8831 | ||
aab5b71e PZ |
8832 | /* |
8833 | * We keep a list of all !task (and therefore per-cpu) events | |
8834 | * that need to receive side-band records. | |
8835 | * | |
8836 | * This avoids having to scan all the various PMU per-cpu contexts | |
8837 | * looking for them. | |
8838 | */ | |
f2fb6bef KL |
8839 | static void account_pmu_sb_event(struct perf_event *event) |
8840 | { | |
a4f144eb | 8841 | if (is_sb_event(event)) |
f2fb6bef KL |
8842 | attach_sb_event(event); |
8843 | } | |
8844 | ||
4beb31f3 FW |
8845 | static void account_event_cpu(struct perf_event *event, int cpu) |
8846 | { | |
8847 | if (event->parent) | |
8848 | return; | |
8849 | ||
4beb31f3 FW |
8850 | if (is_cgroup_event(event)) |
8851 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
8852 | } | |
8853 | ||
555e0c1e FW |
8854 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
8855 | static void account_freq_event_nohz(void) | |
8856 | { | |
8857 | #ifdef CONFIG_NO_HZ_FULL | |
8858 | /* Lock so we don't race with concurrent unaccount */ | |
8859 | spin_lock(&nr_freq_lock); | |
8860 | if (atomic_inc_return(&nr_freq_events) == 1) | |
8861 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
8862 | spin_unlock(&nr_freq_lock); | |
8863 | #endif | |
8864 | } | |
8865 | ||
8866 | static void account_freq_event(void) | |
8867 | { | |
8868 | if (tick_nohz_full_enabled()) | |
8869 | account_freq_event_nohz(); | |
8870 | else | |
8871 | atomic_inc(&nr_freq_events); | |
8872 | } | |
8873 | ||
8874 | ||
766d6c07 FW |
8875 | static void account_event(struct perf_event *event) |
8876 | { | |
25432ae9 PZ |
8877 | bool inc = false; |
8878 | ||
4beb31f3 FW |
8879 | if (event->parent) |
8880 | return; | |
8881 | ||
766d6c07 | 8882 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 8883 | inc = true; |
766d6c07 FW |
8884 | if (event->attr.mmap || event->attr.mmap_data) |
8885 | atomic_inc(&nr_mmap_events); | |
8886 | if (event->attr.comm) | |
8887 | atomic_inc(&nr_comm_events); | |
8888 | if (event->attr.task) | |
8889 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
8890 | if (event->attr.freq) |
8891 | account_freq_event(); | |
45ac1403 AH |
8892 | if (event->attr.context_switch) { |
8893 | atomic_inc(&nr_switch_events); | |
25432ae9 | 8894 | inc = true; |
45ac1403 | 8895 | } |
4beb31f3 | 8896 | if (has_branch_stack(event)) |
25432ae9 | 8897 | inc = true; |
4beb31f3 | 8898 | if (is_cgroup_event(event)) |
25432ae9 PZ |
8899 | inc = true; |
8900 | ||
9107c89e PZ |
8901 | if (inc) { |
8902 | if (atomic_inc_not_zero(&perf_sched_count)) | |
8903 | goto enabled; | |
8904 | ||
8905 | mutex_lock(&perf_sched_mutex); | |
8906 | if (!atomic_read(&perf_sched_count)) { | |
8907 | static_branch_enable(&perf_sched_events); | |
8908 | /* | |
8909 | * Guarantee that all CPUs observe they key change and | |
8910 | * call the perf scheduling hooks before proceeding to | |
8911 | * install events that need them. | |
8912 | */ | |
8913 | synchronize_sched(); | |
8914 | } | |
8915 | /* | |
8916 | * Now that we have waited for the sync_sched(), allow further | |
8917 | * increments to by-pass the mutex. | |
8918 | */ | |
8919 | atomic_inc(&perf_sched_count); | |
8920 | mutex_unlock(&perf_sched_mutex); | |
8921 | } | |
8922 | enabled: | |
4beb31f3 FW |
8923 | |
8924 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
8925 | |
8926 | account_pmu_sb_event(event); | |
766d6c07 FW |
8927 | } |
8928 | ||
0793a61d | 8929 | /* |
cdd6c482 | 8930 | * Allocate and initialize a event structure |
0793a61d | 8931 | */ |
cdd6c482 | 8932 | static struct perf_event * |
c3f00c70 | 8933 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
8934 | struct task_struct *task, |
8935 | struct perf_event *group_leader, | |
8936 | struct perf_event *parent_event, | |
4dc0da86 | 8937 | perf_overflow_handler_t overflow_handler, |
79dff51e | 8938 | void *context, int cgroup_fd) |
0793a61d | 8939 | { |
51b0fe39 | 8940 | struct pmu *pmu; |
cdd6c482 IM |
8941 | struct perf_event *event; |
8942 | struct hw_perf_event *hwc; | |
90983b16 | 8943 | long err = -EINVAL; |
0793a61d | 8944 | |
66832eb4 ON |
8945 | if ((unsigned)cpu >= nr_cpu_ids) { |
8946 | if (!task || cpu != -1) | |
8947 | return ERR_PTR(-EINVAL); | |
8948 | } | |
8949 | ||
c3f00c70 | 8950 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 8951 | if (!event) |
d5d2bc0d | 8952 | return ERR_PTR(-ENOMEM); |
0793a61d | 8953 | |
04289bb9 | 8954 | /* |
cdd6c482 | 8955 | * Single events are their own group leaders, with an |
04289bb9 IM |
8956 | * empty sibling list: |
8957 | */ | |
8958 | if (!group_leader) | |
cdd6c482 | 8959 | group_leader = event; |
04289bb9 | 8960 | |
cdd6c482 IM |
8961 | mutex_init(&event->child_mutex); |
8962 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 8963 | |
cdd6c482 IM |
8964 | INIT_LIST_HEAD(&event->group_entry); |
8965 | INIT_LIST_HEAD(&event->event_entry); | |
8966 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 8967 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 8968 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 8969 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
8970 | INIT_HLIST_NODE(&event->hlist_entry); |
8971 | ||
10c6db11 | 8972 | |
cdd6c482 | 8973 | init_waitqueue_head(&event->waitq); |
e360adbe | 8974 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 8975 | |
cdd6c482 | 8976 | mutex_init(&event->mmap_mutex); |
375637bc | 8977 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 8978 | |
a6fa941d | 8979 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
8980 | event->cpu = cpu; |
8981 | event->attr = *attr; | |
8982 | event->group_leader = group_leader; | |
8983 | event->pmu = NULL; | |
cdd6c482 | 8984 | event->oncpu = -1; |
a96bbc16 | 8985 | |
cdd6c482 | 8986 | event->parent = parent_event; |
b84fbc9f | 8987 | |
17cf22c3 | 8988 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 8989 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 8990 | |
cdd6c482 | 8991 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 8992 | |
d580ff86 PZ |
8993 | if (task) { |
8994 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 8995 | /* |
50f16a8b PZ |
8996 | * XXX pmu::event_init needs to know what task to account to |
8997 | * and we cannot use the ctx information because we need the | |
8998 | * pmu before we get a ctx. | |
d580ff86 | 8999 | */ |
50f16a8b | 9000 | event->hw.target = task; |
d580ff86 PZ |
9001 | } |
9002 | ||
34f43927 PZ |
9003 | event->clock = &local_clock; |
9004 | if (parent_event) | |
9005 | event->clock = parent_event->clock; | |
9006 | ||
4dc0da86 | 9007 | if (!overflow_handler && parent_event) { |
b326e956 | 9008 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
9009 | context = parent_event->overflow_handler_context; |
9010 | } | |
66832eb4 | 9011 | |
1879445d WN |
9012 | if (overflow_handler) { |
9013 | event->overflow_handler = overflow_handler; | |
9014 | event->overflow_handler_context = context; | |
9ecda41a WN |
9015 | } else if (is_write_backward(event)){ |
9016 | event->overflow_handler = perf_event_output_backward; | |
9017 | event->overflow_handler_context = NULL; | |
1879445d | 9018 | } else { |
9ecda41a | 9019 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9020 | event->overflow_handler_context = NULL; |
9021 | } | |
97eaf530 | 9022 | |
0231bb53 | 9023 | perf_event__state_init(event); |
a86ed508 | 9024 | |
4aeb0b42 | 9025 | pmu = NULL; |
b8e83514 | 9026 | |
cdd6c482 | 9027 | hwc = &event->hw; |
bd2b5b12 | 9028 | hwc->sample_period = attr->sample_period; |
0d48696f | 9029 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9030 | hwc->sample_period = 1; |
eced1dfc | 9031 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9032 | |
e7850595 | 9033 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9034 | |
2023b359 | 9035 | /* |
cdd6c482 | 9036 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 9037 | */ |
3dab77fb | 9038 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 9039 | goto err_ns; |
a46a2300 YZ |
9040 | |
9041 | if (!has_branch_stack(event)) | |
9042 | event->attr.branch_sample_type = 0; | |
2023b359 | 9043 | |
79dff51e MF |
9044 | if (cgroup_fd != -1) { |
9045 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9046 | if (err) | |
9047 | goto err_ns; | |
9048 | } | |
9049 | ||
b0a873eb | 9050 | pmu = perf_init_event(event); |
4aeb0b42 | 9051 | if (!pmu) |
90983b16 FW |
9052 | goto err_ns; |
9053 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 9054 | err = PTR_ERR(pmu); |
90983b16 | 9055 | goto err_ns; |
621a01ea | 9056 | } |
d5d2bc0d | 9057 | |
bed5b25a AS |
9058 | err = exclusive_event_init(event); |
9059 | if (err) | |
9060 | goto err_pmu; | |
9061 | ||
375637bc AS |
9062 | if (has_addr_filter(event)) { |
9063 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9064 | sizeof(unsigned long), | |
9065 | GFP_KERNEL); | |
9066 | if (!event->addr_filters_offs) | |
9067 | goto err_per_task; | |
9068 | ||
9069 | /* force hw sync on the address filters */ | |
9070 | event->addr_filters_gen = 1; | |
9071 | } | |
9072 | ||
cdd6c482 | 9073 | if (!event->parent) { |
927c7a9e | 9074 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9075 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9076 | if (err) |
375637bc | 9077 | goto err_addr_filters; |
d010b332 | 9078 | } |
f344011c | 9079 | } |
9ee318a7 | 9080 | |
927a5570 AS |
9081 | /* symmetric to unaccount_event() in _free_event() */ |
9082 | account_event(event); | |
9083 | ||
cdd6c482 | 9084 | return event; |
90983b16 | 9085 | |
375637bc AS |
9086 | err_addr_filters: |
9087 | kfree(event->addr_filters_offs); | |
9088 | ||
bed5b25a AS |
9089 | err_per_task: |
9090 | exclusive_event_destroy(event); | |
9091 | ||
90983b16 FW |
9092 | err_pmu: |
9093 | if (event->destroy) | |
9094 | event->destroy(event); | |
c464c76e | 9095 | module_put(pmu->module); |
90983b16 | 9096 | err_ns: |
79dff51e MF |
9097 | if (is_cgroup_event(event)) |
9098 | perf_detach_cgroup(event); | |
90983b16 FW |
9099 | if (event->ns) |
9100 | put_pid_ns(event->ns); | |
9101 | kfree(event); | |
9102 | ||
9103 | return ERR_PTR(err); | |
0793a61d TG |
9104 | } |
9105 | ||
cdd6c482 IM |
9106 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9107 | struct perf_event_attr *attr) | |
974802ea | 9108 | { |
974802ea | 9109 | u32 size; |
cdf8073d | 9110 | int ret; |
974802ea PZ |
9111 | |
9112 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9113 | return -EFAULT; | |
9114 | ||
9115 | /* | |
9116 | * zero the full structure, so that a short copy will be nice. | |
9117 | */ | |
9118 | memset(attr, 0, sizeof(*attr)); | |
9119 | ||
9120 | ret = get_user(size, &uattr->size); | |
9121 | if (ret) | |
9122 | return ret; | |
9123 | ||
9124 | if (size > PAGE_SIZE) /* silly large */ | |
9125 | goto err_size; | |
9126 | ||
9127 | if (!size) /* abi compat */ | |
9128 | size = PERF_ATTR_SIZE_VER0; | |
9129 | ||
9130 | if (size < PERF_ATTR_SIZE_VER0) | |
9131 | goto err_size; | |
9132 | ||
9133 | /* | |
9134 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9135 | * ensure all the unknown bits are 0 - i.e. new |
9136 | * user-space does not rely on any kernel feature | |
9137 | * extensions we dont know about yet. | |
974802ea PZ |
9138 | */ |
9139 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9140 | unsigned char __user *addr; |
9141 | unsigned char __user *end; | |
9142 | unsigned char val; | |
974802ea | 9143 | |
cdf8073d IS |
9144 | addr = (void __user *)uattr + sizeof(*attr); |
9145 | end = (void __user *)uattr + size; | |
974802ea | 9146 | |
cdf8073d | 9147 | for (; addr < end; addr++) { |
974802ea PZ |
9148 | ret = get_user(val, addr); |
9149 | if (ret) | |
9150 | return ret; | |
9151 | if (val) | |
9152 | goto err_size; | |
9153 | } | |
b3e62e35 | 9154 | size = sizeof(*attr); |
974802ea PZ |
9155 | } |
9156 | ||
9157 | ret = copy_from_user(attr, uattr, size); | |
9158 | if (ret) | |
9159 | return -EFAULT; | |
9160 | ||
cd757645 | 9161 | if (attr->__reserved_1) |
974802ea PZ |
9162 | return -EINVAL; |
9163 | ||
9164 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9165 | return -EINVAL; | |
9166 | ||
9167 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9168 | return -EINVAL; | |
9169 | ||
bce38cd5 SE |
9170 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9171 | u64 mask = attr->branch_sample_type; | |
9172 | ||
9173 | /* only using defined bits */ | |
9174 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9175 | return -EINVAL; | |
9176 | ||
9177 | /* at least one branch bit must be set */ | |
9178 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9179 | return -EINVAL; | |
9180 | ||
bce38cd5 SE |
9181 | /* propagate priv level, when not set for branch */ |
9182 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9183 | ||
9184 | /* exclude_kernel checked on syscall entry */ | |
9185 | if (!attr->exclude_kernel) | |
9186 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9187 | ||
9188 | if (!attr->exclude_user) | |
9189 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9190 | ||
9191 | if (!attr->exclude_hv) | |
9192 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9193 | /* | |
9194 | * adjust user setting (for HW filter setup) | |
9195 | */ | |
9196 | attr->branch_sample_type = mask; | |
9197 | } | |
e712209a SE |
9198 | /* privileged levels capture (kernel, hv): check permissions */ |
9199 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9200 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9201 | return -EACCES; | |
bce38cd5 | 9202 | } |
4018994f | 9203 | |
c5ebcedb | 9204 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9205 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9206 | if (ret) |
9207 | return ret; | |
9208 | } | |
9209 | ||
9210 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9211 | if (!arch_perf_have_user_stack_dump()) | |
9212 | return -ENOSYS; | |
9213 | ||
9214 | /* | |
9215 | * We have __u32 type for the size, but so far | |
9216 | * we can only use __u16 as maximum due to the | |
9217 | * __u16 sample size limit. | |
9218 | */ | |
9219 | if (attr->sample_stack_user >= USHRT_MAX) | |
9220 | ret = -EINVAL; | |
9221 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9222 | ret = -EINVAL; | |
9223 | } | |
4018994f | 9224 | |
60e2364e SE |
9225 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9226 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9227 | out: |
9228 | return ret; | |
9229 | ||
9230 | err_size: | |
9231 | put_user(sizeof(*attr), &uattr->size); | |
9232 | ret = -E2BIG; | |
9233 | goto out; | |
9234 | } | |
9235 | ||
ac9721f3 PZ |
9236 | static int |
9237 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9238 | { |
b69cf536 | 9239 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9240 | int ret = -EINVAL; |
9241 | ||
ac9721f3 | 9242 | if (!output_event) |
a4be7c27 PZ |
9243 | goto set; |
9244 | ||
ac9721f3 PZ |
9245 | /* don't allow circular references */ |
9246 | if (event == output_event) | |
a4be7c27 PZ |
9247 | goto out; |
9248 | ||
0f139300 PZ |
9249 | /* |
9250 | * Don't allow cross-cpu buffers | |
9251 | */ | |
9252 | if (output_event->cpu != event->cpu) | |
9253 | goto out; | |
9254 | ||
9255 | /* | |
76369139 | 9256 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9257 | */ |
9258 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9259 | goto out; | |
9260 | ||
34f43927 PZ |
9261 | /* |
9262 | * Mixing clocks in the same buffer is trouble you don't need. | |
9263 | */ | |
9264 | if (output_event->clock != event->clock) | |
9265 | goto out; | |
9266 | ||
9ecda41a WN |
9267 | /* |
9268 | * Either writing ring buffer from beginning or from end. | |
9269 | * Mixing is not allowed. | |
9270 | */ | |
9271 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9272 | goto out; | |
9273 | ||
45bfb2e5 PZ |
9274 | /* |
9275 | * If both events generate aux data, they must be on the same PMU | |
9276 | */ | |
9277 | if (has_aux(event) && has_aux(output_event) && | |
9278 | event->pmu != output_event->pmu) | |
9279 | goto out; | |
9280 | ||
a4be7c27 | 9281 | set: |
cdd6c482 | 9282 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9283 | /* Can't redirect output if we've got an active mmap() */ |
9284 | if (atomic_read(&event->mmap_count)) | |
9285 | goto unlock; | |
a4be7c27 | 9286 | |
ac9721f3 | 9287 | if (output_event) { |
76369139 FW |
9288 | /* get the rb we want to redirect to */ |
9289 | rb = ring_buffer_get(output_event); | |
9290 | if (!rb) | |
ac9721f3 | 9291 | goto unlock; |
a4be7c27 PZ |
9292 | } |
9293 | ||
b69cf536 | 9294 | ring_buffer_attach(event, rb); |
9bb5d40c | 9295 | |
a4be7c27 | 9296 | ret = 0; |
ac9721f3 PZ |
9297 | unlock: |
9298 | mutex_unlock(&event->mmap_mutex); | |
9299 | ||
a4be7c27 | 9300 | out: |
a4be7c27 PZ |
9301 | return ret; |
9302 | } | |
9303 | ||
f63a8daa PZ |
9304 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9305 | { | |
9306 | if (b < a) | |
9307 | swap(a, b); | |
9308 | ||
9309 | mutex_lock(a); | |
9310 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9311 | } | |
9312 | ||
34f43927 PZ |
9313 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9314 | { | |
9315 | bool nmi_safe = false; | |
9316 | ||
9317 | switch (clk_id) { | |
9318 | case CLOCK_MONOTONIC: | |
9319 | event->clock = &ktime_get_mono_fast_ns; | |
9320 | nmi_safe = true; | |
9321 | break; | |
9322 | ||
9323 | case CLOCK_MONOTONIC_RAW: | |
9324 | event->clock = &ktime_get_raw_fast_ns; | |
9325 | nmi_safe = true; | |
9326 | break; | |
9327 | ||
9328 | case CLOCK_REALTIME: | |
9329 | event->clock = &ktime_get_real_ns; | |
9330 | break; | |
9331 | ||
9332 | case CLOCK_BOOTTIME: | |
9333 | event->clock = &ktime_get_boot_ns; | |
9334 | break; | |
9335 | ||
9336 | case CLOCK_TAI: | |
9337 | event->clock = &ktime_get_tai_ns; | |
9338 | break; | |
9339 | ||
9340 | default: | |
9341 | return -EINVAL; | |
9342 | } | |
9343 | ||
9344 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9345 | return -EINVAL; | |
9346 | ||
9347 | return 0; | |
9348 | } | |
9349 | ||
0793a61d | 9350 | /** |
cdd6c482 | 9351 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9352 | * |
cdd6c482 | 9353 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9354 | * @pid: target pid |
9f66a381 | 9355 | * @cpu: target cpu |
cdd6c482 | 9356 | * @group_fd: group leader event fd |
0793a61d | 9357 | */ |
cdd6c482 IM |
9358 | SYSCALL_DEFINE5(perf_event_open, |
9359 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9360 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9361 | { |
b04243ef PZ |
9362 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9363 | struct perf_event *event, *sibling; | |
cdd6c482 | 9364 | struct perf_event_attr attr; |
f63a8daa | 9365 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9366 | struct file *event_file = NULL; |
2903ff01 | 9367 | struct fd group = {NULL, 0}; |
38a81da2 | 9368 | struct task_struct *task = NULL; |
89a1e187 | 9369 | struct pmu *pmu; |
ea635c64 | 9370 | int event_fd; |
b04243ef | 9371 | int move_group = 0; |
dc86cabe | 9372 | int err; |
a21b0b35 | 9373 | int f_flags = O_RDWR; |
79dff51e | 9374 | int cgroup_fd = -1; |
0793a61d | 9375 | |
2743a5b0 | 9376 | /* for future expandability... */ |
e5d1367f | 9377 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9378 | return -EINVAL; |
9379 | ||
dc86cabe IM |
9380 | err = perf_copy_attr(attr_uptr, &attr); |
9381 | if (err) | |
9382 | return err; | |
eab656ae | 9383 | |
0764771d PZ |
9384 | if (!attr.exclude_kernel) { |
9385 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9386 | return -EACCES; | |
9387 | } | |
9388 | ||
df58ab24 | 9389 | if (attr.freq) { |
cdd6c482 | 9390 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9391 | return -EINVAL; |
0819b2e3 PZ |
9392 | } else { |
9393 | if (attr.sample_period & (1ULL << 63)) | |
9394 | return -EINVAL; | |
df58ab24 PZ |
9395 | } |
9396 | ||
97c79a38 ACM |
9397 | if (!attr.sample_max_stack) |
9398 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9399 | ||
e5d1367f SE |
9400 | /* |
9401 | * In cgroup mode, the pid argument is used to pass the fd | |
9402 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9403 | * designates the cpu on which to monitor threads from that | |
9404 | * cgroup. | |
9405 | */ | |
9406 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9407 | return -EINVAL; | |
9408 | ||
a21b0b35 YD |
9409 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9410 | f_flags |= O_CLOEXEC; | |
9411 | ||
9412 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9413 | if (event_fd < 0) |
9414 | return event_fd; | |
9415 | ||
ac9721f3 | 9416 | if (group_fd != -1) { |
2903ff01 AV |
9417 | err = perf_fget_light(group_fd, &group); |
9418 | if (err) | |
d14b12d7 | 9419 | goto err_fd; |
2903ff01 | 9420 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9421 | if (flags & PERF_FLAG_FD_OUTPUT) |
9422 | output_event = group_leader; | |
9423 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9424 | group_leader = NULL; | |
9425 | } | |
9426 | ||
e5d1367f | 9427 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9428 | task = find_lively_task_by_vpid(pid); |
9429 | if (IS_ERR(task)) { | |
9430 | err = PTR_ERR(task); | |
9431 | goto err_group_fd; | |
9432 | } | |
9433 | } | |
9434 | ||
1f4ee503 PZ |
9435 | if (task && group_leader && |
9436 | group_leader->attr.inherit != attr.inherit) { | |
9437 | err = -EINVAL; | |
9438 | goto err_task; | |
9439 | } | |
9440 | ||
fbfc623f YZ |
9441 | get_online_cpus(); |
9442 | ||
79c9ce57 PZ |
9443 | if (task) { |
9444 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9445 | if (err) | |
9446 | goto err_cpus; | |
9447 | ||
9448 | /* | |
9449 | * Reuse ptrace permission checks for now. | |
9450 | * | |
9451 | * We must hold cred_guard_mutex across this and any potential | |
9452 | * perf_install_in_context() call for this new event to | |
9453 | * serialize against exec() altering our credentials (and the | |
9454 | * perf_event_exit_task() that could imply). | |
9455 | */ | |
9456 | err = -EACCES; | |
9457 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9458 | goto err_cred; | |
9459 | } | |
9460 | ||
79dff51e MF |
9461 | if (flags & PERF_FLAG_PID_CGROUP) |
9462 | cgroup_fd = pid; | |
9463 | ||
4dc0da86 | 9464 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9465 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9466 | if (IS_ERR(event)) { |
9467 | err = PTR_ERR(event); | |
79c9ce57 | 9468 | goto err_cred; |
d14b12d7 SE |
9469 | } |
9470 | ||
53b25335 VW |
9471 | if (is_sampling_event(event)) { |
9472 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9473 | err = -EOPNOTSUPP; |
53b25335 VW |
9474 | goto err_alloc; |
9475 | } | |
9476 | } | |
9477 | ||
89a1e187 PZ |
9478 | /* |
9479 | * Special case software events and allow them to be part of | |
9480 | * any hardware group. | |
9481 | */ | |
9482 | pmu = event->pmu; | |
b04243ef | 9483 | |
34f43927 PZ |
9484 | if (attr.use_clockid) { |
9485 | err = perf_event_set_clock(event, attr.clockid); | |
9486 | if (err) | |
9487 | goto err_alloc; | |
9488 | } | |
9489 | ||
4ff6a8de DCC |
9490 | if (pmu->task_ctx_nr == perf_sw_context) |
9491 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
9492 | ||
b04243ef PZ |
9493 | if (group_leader && |
9494 | (is_software_event(event) != is_software_event(group_leader))) { | |
9495 | if (is_software_event(event)) { | |
9496 | /* | |
9497 | * If event and group_leader are not both a software | |
9498 | * event, and event is, then group leader is not. | |
9499 | * | |
9500 | * Allow the addition of software events to !software | |
9501 | * groups, this is safe because software events never | |
9502 | * fail to schedule. | |
9503 | */ | |
9504 | pmu = group_leader->pmu; | |
9505 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 9506 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
9507 | /* |
9508 | * In case the group is a pure software group, and we | |
9509 | * try to add a hardware event, move the whole group to | |
9510 | * the hardware context. | |
9511 | */ | |
9512 | move_group = 1; | |
9513 | } | |
9514 | } | |
89a1e187 PZ |
9515 | |
9516 | /* | |
9517 | * Get the target context (task or percpu): | |
9518 | */ | |
4af57ef2 | 9519 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9520 | if (IS_ERR(ctx)) { |
9521 | err = PTR_ERR(ctx); | |
c6be5a5c | 9522 | goto err_alloc; |
89a1e187 PZ |
9523 | } |
9524 | ||
bed5b25a AS |
9525 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9526 | err = -EBUSY; | |
9527 | goto err_context; | |
9528 | } | |
9529 | ||
ccff286d | 9530 | /* |
cdd6c482 | 9531 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9532 | */ |
ac9721f3 | 9533 | if (group_leader) { |
dc86cabe | 9534 | err = -EINVAL; |
04289bb9 | 9535 | |
04289bb9 | 9536 | /* |
ccff286d IM |
9537 | * Do not allow a recursive hierarchy (this new sibling |
9538 | * becoming part of another group-sibling): | |
9539 | */ | |
9540 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9541 | goto err_context; |
34f43927 PZ |
9542 | |
9543 | /* All events in a group should have the same clock */ | |
9544 | if (group_leader->clock != event->clock) | |
9545 | goto err_context; | |
9546 | ||
ccff286d IM |
9547 | /* |
9548 | * Do not allow to attach to a group in a different | |
9549 | * task or CPU context: | |
04289bb9 | 9550 | */ |
b04243ef | 9551 | if (move_group) { |
c3c87e77 PZ |
9552 | /* |
9553 | * Make sure we're both on the same task, or both | |
9554 | * per-cpu events. | |
9555 | */ | |
9556 | if (group_leader->ctx->task != ctx->task) | |
9557 | goto err_context; | |
9558 | ||
9559 | /* | |
9560 | * Make sure we're both events for the same CPU; | |
9561 | * grouping events for different CPUs is broken; since | |
9562 | * you can never concurrently schedule them anyhow. | |
9563 | */ | |
9564 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
9565 | goto err_context; |
9566 | } else { | |
9567 | if (group_leader->ctx != ctx) | |
9568 | goto err_context; | |
9569 | } | |
9570 | ||
3b6f9e5c PM |
9571 | /* |
9572 | * Only a group leader can be exclusive or pinned | |
9573 | */ | |
0d48696f | 9574 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 9575 | goto err_context; |
ac9721f3 PZ |
9576 | } |
9577 | ||
9578 | if (output_event) { | |
9579 | err = perf_event_set_output(event, output_event); | |
9580 | if (err) | |
c3f00c70 | 9581 | goto err_context; |
ac9721f3 | 9582 | } |
0793a61d | 9583 | |
a21b0b35 YD |
9584 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
9585 | f_flags); | |
ea635c64 AV |
9586 | if (IS_ERR(event_file)) { |
9587 | err = PTR_ERR(event_file); | |
201c2f85 | 9588 | event_file = NULL; |
c3f00c70 | 9589 | goto err_context; |
ea635c64 | 9590 | } |
9b51f66d | 9591 | |
b04243ef | 9592 | if (move_group) { |
f63a8daa | 9593 | gctx = group_leader->ctx; |
f55fc2a5 | 9594 | mutex_lock_double(&gctx->mutex, &ctx->mutex); |
84c4e620 PZ |
9595 | if (gctx->task == TASK_TOMBSTONE) { |
9596 | err = -ESRCH; | |
9597 | goto err_locked; | |
9598 | } | |
f55fc2a5 PZ |
9599 | } else { |
9600 | mutex_lock(&ctx->mutex); | |
9601 | } | |
9602 | ||
84c4e620 PZ |
9603 | if (ctx->task == TASK_TOMBSTONE) { |
9604 | err = -ESRCH; | |
9605 | goto err_locked; | |
9606 | } | |
9607 | ||
a723968c PZ |
9608 | if (!perf_event_validate_size(event)) { |
9609 | err = -E2BIG; | |
9610 | goto err_locked; | |
9611 | } | |
9612 | ||
f55fc2a5 PZ |
9613 | /* |
9614 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
9615 | * because we need to serialize with concurrent event creation. | |
9616 | */ | |
9617 | if (!exclusive_event_installable(event, ctx)) { | |
9618 | /* exclusive and group stuff are assumed mutually exclusive */ | |
9619 | WARN_ON_ONCE(move_group); | |
f63a8daa | 9620 | |
f55fc2a5 PZ |
9621 | err = -EBUSY; |
9622 | goto err_locked; | |
9623 | } | |
f63a8daa | 9624 | |
f55fc2a5 PZ |
9625 | WARN_ON_ONCE(ctx->parent_ctx); |
9626 | ||
79c9ce57 PZ |
9627 | /* |
9628 | * This is the point on no return; we cannot fail hereafter. This is | |
9629 | * where we start modifying current state. | |
9630 | */ | |
9631 | ||
f55fc2a5 | 9632 | if (move_group) { |
f63a8daa PZ |
9633 | /* |
9634 | * See perf_event_ctx_lock() for comments on the details | |
9635 | * of swizzling perf_event::ctx. | |
9636 | */ | |
45a0e07a | 9637 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 9638 | |
b04243ef PZ |
9639 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9640 | group_entry) { | |
45a0e07a | 9641 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
9642 | put_ctx(gctx); |
9643 | } | |
b04243ef | 9644 | |
f63a8daa PZ |
9645 | /* |
9646 | * Wait for everybody to stop referencing the events through | |
9647 | * the old lists, before installing it on new lists. | |
9648 | */ | |
0cda4c02 | 9649 | synchronize_rcu(); |
f63a8daa | 9650 | |
8f95b435 PZI |
9651 | /* |
9652 | * Install the group siblings before the group leader. | |
9653 | * | |
9654 | * Because a group leader will try and install the entire group | |
9655 | * (through the sibling list, which is still in-tact), we can | |
9656 | * end up with siblings installed in the wrong context. | |
9657 | * | |
9658 | * By installing siblings first we NO-OP because they're not | |
9659 | * reachable through the group lists. | |
9660 | */ | |
b04243ef PZ |
9661 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9662 | group_entry) { | |
8f95b435 | 9663 | perf_event__state_init(sibling); |
9fc81d87 | 9664 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
9665 | get_ctx(ctx); |
9666 | } | |
8f95b435 PZI |
9667 | |
9668 | /* | |
9669 | * Removing from the context ends up with disabled | |
9670 | * event. What we want here is event in the initial | |
9671 | * startup state, ready to be add into new context. | |
9672 | */ | |
9673 | perf_event__state_init(group_leader); | |
9674 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
9675 | get_ctx(ctx); | |
b04243ef | 9676 | |
f55fc2a5 PZ |
9677 | /* |
9678 | * Now that all events are installed in @ctx, nothing | |
9679 | * references @gctx anymore, so drop the last reference we have | |
9680 | * on it. | |
9681 | */ | |
9682 | put_ctx(gctx); | |
bed5b25a AS |
9683 | } |
9684 | ||
f73e22ab PZ |
9685 | /* |
9686 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
9687 | * that we're serialized against further additions and before | |
9688 | * perf_install_in_context() which is the point the event is active and | |
9689 | * can use these values. | |
9690 | */ | |
9691 | perf_event__header_size(event); | |
9692 | perf_event__id_header_size(event); | |
9693 | ||
78cd2c74 PZ |
9694 | event->owner = current; |
9695 | ||
e2d37cd2 | 9696 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 9697 | perf_unpin_context(ctx); |
f63a8daa | 9698 | |
f55fc2a5 | 9699 | if (move_group) |
f63a8daa | 9700 | mutex_unlock(&gctx->mutex); |
d859e29f | 9701 | mutex_unlock(&ctx->mutex); |
9b51f66d | 9702 | |
79c9ce57 PZ |
9703 | if (task) { |
9704 | mutex_unlock(&task->signal->cred_guard_mutex); | |
9705 | put_task_struct(task); | |
9706 | } | |
9707 | ||
fbfc623f YZ |
9708 | put_online_cpus(); |
9709 | ||
cdd6c482 IM |
9710 | mutex_lock(¤t->perf_event_mutex); |
9711 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
9712 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 9713 | |
8a49542c PZ |
9714 | /* |
9715 | * Drop the reference on the group_event after placing the | |
9716 | * new event on the sibling_list. This ensures destruction | |
9717 | * of the group leader will find the pointer to itself in | |
9718 | * perf_group_detach(). | |
9719 | */ | |
2903ff01 | 9720 | fdput(group); |
ea635c64 AV |
9721 | fd_install(event_fd, event_file); |
9722 | return event_fd; | |
0793a61d | 9723 | |
f55fc2a5 PZ |
9724 | err_locked: |
9725 | if (move_group) | |
9726 | mutex_unlock(&gctx->mutex); | |
9727 | mutex_unlock(&ctx->mutex); | |
9728 | /* err_file: */ | |
9729 | fput(event_file); | |
c3f00c70 | 9730 | err_context: |
fe4b04fa | 9731 | perf_unpin_context(ctx); |
ea635c64 | 9732 | put_ctx(ctx); |
c6be5a5c | 9733 | err_alloc: |
13005627 PZ |
9734 | /* |
9735 | * If event_file is set, the fput() above will have called ->release() | |
9736 | * and that will take care of freeing the event. | |
9737 | */ | |
9738 | if (!event_file) | |
9739 | free_event(event); | |
79c9ce57 PZ |
9740 | err_cred: |
9741 | if (task) | |
9742 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 9743 | err_cpus: |
fbfc623f | 9744 | put_online_cpus(); |
1f4ee503 | 9745 | err_task: |
e7d0bc04 PZ |
9746 | if (task) |
9747 | put_task_struct(task); | |
89a1e187 | 9748 | err_group_fd: |
2903ff01 | 9749 | fdput(group); |
ea635c64 AV |
9750 | err_fd: |
9751 | put_unused_fd(event_fd); | |
dc86cabe | 9752 | return err; |
0793a61d TG |
9753 | } |
9754 | ||
fb0459d7 AV |
9755 | /** |
9756 | * perf_event_create_kernel_counter | |
9757 | * | |
9758 | * @attr: attributes of the counter to create | |
9759 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 9760 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
9761 | */ |
9762 | struct perf_event * | |
9763 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 9764 | struct task_struct *task, |
4dc0da86 AK |
9765 | perf_overflow_handler_t overflow_handler, |
9766 | void *context) | |
fb0459d7 | 9767 | { |
fb0459d7 | 9768 | struct perf_event_context *ctx; |
c3f00c70 | 9769 | struct perf_event *event; |
fb0459d7 | 9770 | int err; |
d859e29f | 9771 | |
fb0459d7 AV |
9772 | /* |
9773 | * Get the target context (task or percpu): | |
9774 | */ | |
d859e29f | 9775 | |
4dc0da86 | 9776 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 9777 | overflow_handler, context, -1); |
c3f00c70 PZ |
9778 | if (IS_ERR(event)) { |
9779 | err = PTR_ERR(event); | |
9780 | goto err; | |
9781 | } | |
d859e29f | 9782 | |
f8697762 | 9783 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 9784 | event->owner = TASK_TOMBSTONE; |
f8697762 | 9785 | |
4af57ef2 | 9786 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
9787 | if (IS_ERR(ctx)) { |
9788 | err = PTR_ERR(ctx); | |
c3f00c70 | 9789 | goto err_free; |
d859e29f | 9790 | } |
fb0459d7 | 9791 | |
fb0459d7 AV |
9792 | WARN_ON_ONCE(ctx->parent_ctx); |
9793 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
9794 | if (ctx->task == TASK_TOMBSTONE) { |
9795 | err = -ESRCH; | |
9796 | goto err_unlock; | |
9797 | } | |
9798 | ||
bed5b25a | 9799 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 9800 | err = -EBUSY; |
84c4e620 | 9801 | goto err_unlock; |
bed5b25a AS |
9802 | } |
9803 | ||
fb0459d7 | 9804 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 9805 | perf_unpin_context(ctx); |
fb0459d7 AV |
9806 | mutex_unlock(&ctx->mutex); |
9807 | ||
fb0459d7 AV |
9808 | return event; |
9809 | ||
84c4e620 PZ |
9810 | err_unlock: |
9811 | mutex_unlock(&ctx->mutex); | |
9812 | perf_unpin_context(ctx); | |
9813 | put_ctx(ctx); | |
c3f00c70 PZ |
9814 | err_free: |
9815 | free_event(event); | |
9816 | err: | |
c6567f64 | 9817 | return ERR_PTR(err); |
9b51f66d | 9818 | } |
fb0459d7 | 9819 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 9820 | |
0cda4c02 YZ |
9821 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
9822 | { | |
9823 | struct perf_event_context *src_ctx; | |
9824 | struct perf_event_context *dst_ctx; | |
9825 | struct perf_event *event, *tmp; | |
9826 | LIST_HEAD(events); | |
9827 | ||
9828 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
9829 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
9830 | ||
f63a8daa PZ |
9831 | /* |
9832 | * See perf_event_ctx_lock() for comments on the details | |
9833 | * of swizzling perf_event::ctx. | |
9834 | */ | |
9835 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
9836 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
9837 | event_entry) { | |
45a0e07a | 9838 | perf_remove_from_context(event, 0); |
9a545de0 | 9839 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 9840 | put_ctx(src_ctx); |
9886167d | 9841 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 9842 | } |
0cda4c02 | 9843 | |
8f95b435 PZI |
9844 | /* |
9845 | * Wait for the events to quiesce before re-instating them. | |
9846 | */ | |
0cda4c02 YZ |
9847 | synchronize_rcu(); |
9848 | ||
8f95b435 PZI |
9849 | /* |
9850 | * Re-instate events in 2 passes. | |
9851 | * | |
9852 | * Skip over group leaders and only install siblings on this first | |
9853 | * pass, siblings will not get enabled without a leader, however a | |
9854 | * leader will enable its siblings, even if those are still on the old | |
9855 | * context. | |
9856 | */ | |
9857 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
9858 | if (event->group_leader == event) | |
9859 | continue; | |
9860 | ||
9861 | list_del(&event->migrate_entry); | |
9862 | if (event->state >= PERF_EVENT_STATE_OFF) | |
9863 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9864 | account_event_cpu(event, dst_cpu); | |
9865 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
9866 | get_ctx(dst_ctx); | |
9867 | } | |
9868 | ||
9869 | /* | |
9870 | * Once all the siblings are setup properly, install the group leaders | |
9871 | * to make it go. | |
9872 | */ | |
9886167d PZ |
9873 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
9874 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
9875 | if (event->state >= PERF_EVENT_STATE_OFF) |
9876 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 9877 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
9878 | perf_install_in_context(dst_ctx, event, dst_cpu); |
9879 | get_ctx(dst_ctx); | |
9880 | } | |
9881 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 9882 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
9883 | } |
9884 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
9885 | ||
cdd6c482 | 9886 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 9887 | struct task_struct *child) |
d859e29f | 9888 | { |
cdd6c482 | 9889 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 9890 | u64 child_val; |
d859e29f | 9891 | |
cdd6c482 IM |
9892 | if (child_event->attr.inherit_stat) |
9893 | perf_event_read_event(child_event, child); | |
38b200d6 | 9894 | |
b5e58793 | 9895 | child_val = perf_event_count(child_event); |
d859e29f PM |
9896 | |
9897 | /* | |
9898 | * Add back the child's count to the parent's count: | |
9899 | */ | |
a6e6dea6 | 9900 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
9901 | atomic64_add(child_event->total_time_enabled, |
9902 | &parent_event->child_total_time_enabled); | |
9903 | atomic64_add(child_event->total_time_running, | |
9904 | &parent_event->child_total_time_running); | |
d859e29f PM |
9905 | } |
9906 | ||
9b51f66d | 9907 | static void |
8ba289b8 PZ |
9908 | perf_event_exit_event(struct perf_event *child_event, |
9909 | struct perf_event_context *child_ctx, | |
9910 | struct task_struct *child) | |
9b51f66d | 9911 | { |
8ba289b8 PZ |
9912 | struct perf_event *parent_event = child_event->parent; |
9913 | ||
1903d50c PZ |
9914 | /* |
9915 | * Do not destroy the 'original' grouping; because of the context | |
9916 | * switch optimization the original events could've ended up in a | |
9917 | * random child task. | |
9918 | * | |
9919 | * If we were to destroy the original group, all group related | |
9920 | * operations would cease to function properly after this random | |
9921 | * child dies. | |
9922 | * | |
9923 | * Do destroy all inherited groups, we don't care about those | |
9924 | * and being thorough is better. | |
9925 | */ | |
32132a3d PZ |
9926 | raw_spin_lock_irq(&child_ctx->lock); |
9927 | WARN_ON_ONCE(child_ctx->is_active); | |
9928 | ||
8ba289b8 | 9929 | if (parent_event) |
32132a3d PZ |
9930 | perf_group_detach(child_event); |
9931 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 9932 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 9933 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 9934 | |
9b51f66d | 9935 | /* |
8ba289b8 | 9936 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 9937 | */ |
8ba289b8 | 9938 | if (!parent_event) { |
179033b3 | 9939 | perf_event_wakeup(child_event); |
8ba289b8 | 9940 | return; |
4bcf349a | 9941 | } |
8ba289b8 PZ |
9942 | /* |
9943 | * Child events can be cleaned up. | |
9944 | */ | |
9945 | ||
9946 | sync_child_event(child_event, child); | |
9947 | ||
9948 | /* | |
9949 | * Remove this event from the parent's list | |
9950 | */ | |
9951 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
9952 | mutex_lock(&parent_event->child_mutex); | |
9953 | list_del_init(&child_event->child_list); | |
9954 | mutex_unlock(&parent_event->child_mutex); | |
9955 | ||
9956 | /* | |
9957 | * Kick perf_poll() for is_event_hup(). | |
9958 | */ | |
9959 | perf_event_wakeup(parent_event); | |
9960 | free_event(child_event); | |
9961 | put_event(parent_event); | |
9b51f66d IM |
9962 | } |
9963 | ||
8dc85d54 | 9964 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 9965 | { |
211de6eb | 9966 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 9967 | struct perf_event *child_event, *next; |
63b6da39 PZ |
9968 | |
9969 | WARN_ON_ONCE(child != current); | |
9b51f66d | 9970 | |
6a3351b6 | 9971 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 9972 | if (!child_ctx) |
9b51f66d IM |
9973 | return; |
9974 | ||
ad3a37de | 9975 | /* |
6a3351b6 PZ |
9976 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
9977 | * ctx::mutex over the entire thing. This serializes against almost | |
9978 | * everything that wants to access the ctx. | |
9979 | * | |
9980 | * The exception is sys_perf_event_open() / | |
9981 | * perf_event_create_kernel_count() which does find_get_context() | |
9982 | * without ctx::mutex (it cannot because of the move_group double mutex | |
9983 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 9984 | */ |
6a3351b6 | 9985 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
9986 | |
9987 | /* | |
6a3351b6 PZ |
9988 | * In a single ctx::lock section, de-schedule the events and detach the |
9989 | * context from the task such that we cannot ever get it scheduled back | |
9990 | * in. | |
c93f7669 | 9991 | */ |
6a3351b6 | 9992 | raw_spin_lock_irq(&child_ctx->lock); |
63b6da39 | 9993 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx); |
4a1c0f26 | 9994 | |
71a851b4 | 9995 | /* |
63b6da39 PZ |
9996 | * Now that the context is inactive, destroy the task <-> ctx relation |
9997 | * and mark the context dead. | |
71a851b4 | 9998 | */ |
63b6da39 PZ |
9999 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10000 | put_ctx(child_ctx); /* cannot be last */ | |
10001 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10002 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10003 | |
211de6eb | 10004 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10005 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10006 | |
211de6eb PZ |
10007 | if (clone_ctx) |
10008 | put_ctx(clone_ctx); | |
4a1c0f26 | 10009 | |
9f498cc5 | 10010 | /* |
cdd6c482 IM |
10011 | * Report the task dead after unscheduling the events so that we |
10012 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10013 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10014 | */ |
cdd6c482 | 10015 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10016 | |
ebf905fc | 10017 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10018 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10019 | |
a63eaf34 PM |
10020 | mutex_unlock(&child_ctx->mutex); |
10021 | ||
10022 | put_ctx(child_ctx); | |
9b51f66d IM |
10023 | } |
10024 | ||
8dc85d54 PZ |
10025 | /* |
10026 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10027 | * |
10028 | * Can be called with cred_guard_mutex held when called from | |
10029 | * install_exec_creds(). | |
8dc85d54 PZ |
10030 | */ |
10031 | void perf_event_exit_task(struct task_struct *child) | |
10032 | { | |
8882135b | 10033 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10034 | int ctxn; |
10035 | ||
8882135b PZ |
10036 | mutex_lock(&child->perf_event_mutex); |
10037 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10038 | owner_entry) { | |
10039 | list_del_init(&event->owner_entry); | |
10040 | ||
10041 | /* | |
10042 | * Ensure the list deletion is visible before we clear | |
10043 | * the owner, closes a race against perf_release() where | |
10044 | * we need to serialize on the owner->perf_event_mutex. | |
10045 | */ | |
f47c02c0 | 10046 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10047 | } |
10048 | mutex_unlock(&child->perf_event_mutex); | |
10049 | ||
8dc85d54 PZ |
10050 | for_each_task_context_nr(ctxn) |
10051 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10052 | |
10053 | /* | |
10054 | * The perf_event_exit_task_context calls perf_event_task | |
10055 | * with child's task_ctx, which generates EXIT events for | |
10056 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10057 | * At this point we need to send EXIT events to cpu contexts. | |
10058 | */ | |
10059 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10060 | } |
10061 | ||
889ff015 FW |
10062 | static void perf_free_event(struct perf_event *event, |
10063 | struct perf_event_context *ctx) | |
10064 | { | |
10065 | struct perf_event *parent = event->parent; | |
10066 | ||
10067 | if (WARN_ON_ONCE(!parent)) | |
10068 | return; | |
10069 | ||
10070 | mutex_lock(&parent->child_mutex); | |
10071 | list_del_init(&event->child_list); | |
10072 | mutex_unlock(&parent->child_mutex); | |
10073 | ||
a6fa941d | 10074 | put_event(parent); |
889ff015 | 10075 | |
652884fe | 10076 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10077 | perf_group_detach(event); |
889ff015 | 10078 | list_del_event(event, ctx); |
652884fe | 10079 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10080 | free_event(event); |
10081 | } | |
10082 | ||
bbbee908 | 10083 | /* |
652884fe | 10084 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10085 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10086 | * |
10087 | * Not all locks are strictly required, but take them anyway to be nice and | |
10088 | * help out with the lockdep assertions. | |
bbbee908 | 10089 | */ |
cdd6c482 | 10090 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10091 | { |
8dc85d54 | 10092 | struct perf_event_context *ctx; |
cdd6c482 | 10093 | struct perf_event *event, *tmp; |
8dc85d54 | 10094 | int ctxn; |
bbbee908 | 10095 | |
8dc85d54 PZ |
10096 | for_each_task_context_nr(ctxn) { |
10097 | ctx = task->perf_event_ctxp[ctxn]; | |
10098 | if (!ctx) | |
10099 | continue; | |
bbbee908 | 10100 | |
8dc85d54 | 10101 | mutex_lock(&ctx->mutex); |
bbbee908 | 10102 | again: |
8dc85d54 PZ |
10103 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
10104 | group_entry) | |
10105 | perf_free_event(event, ctx); | |
bbbee908 | 10106 | |
8dc85d54 PZ |
10107 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
10108 | group_entry) | |
10109 | perf_free_event(event, ctx); | |
bbbee908 | 10110 | |
8dc85d54 PZ |
10111 | if (!list_empty(&ctx->pinned_groups) || |
10112 | !list_empty(&ctx->flexible_groups)) | |
10113 | goto again; | |
bbbee908 | 10114 | |
8dc85d54 | 10115 | mutex_unlock(&ctx->mutex); |
bbbee908 | 10116 | |
8dc85d54 PZ |
10117 | put_ctx(ctx); |
10118 | } | |
889ff015 FW |
10119 | } |
10120 | ||
4e231c79 PZ |
10121 | void perf_event_delayed_put(struct task_struct *task) |
10122 | { | |
10123 | int ctxn; | |
10124 | ||
10125 | for_each_task_context_nr(ctxn) | |
10126 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10127 | } | |
10128 | ||
e03e7ee3 | 10129 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10130 | { |
e03e7ee3 | 10131 | struct file *file; |
ffe8690c | 10132 | |
e03e7ee3 AS |
10133 | file = fget_raw(fd); |
10134 | if (!file) | |
10135 | return ERR_PTR(-EBADF); | |
ffe8690c | 10136 | |
e03e7ee3 AS |
10137 | if (file->f_op != &perf_fops) { |
10138 | fput(file); | |
10139 | return ERR_PTR(-EBADF); | |
10140 | } | |
ffe8690c | 10141 | |
e03e7ee3 | 10142 | return file; |
ffe8690c KX |
10143 | } |
10144 | ||
10145 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10146 | { | |
10147 | if (!event) | |
10148 | return ERR_PTR(-EINVAL); | |
10149 | ||
10150 | return &event->attr; | |
10151 | } | |
10152 | ||
97dee4f3 PZ |
10153 | /* |
10154 | * inherit a event from parent task to child task: | |
10155 | */ | |
10156 | static struct perf_event * | |
10157 | inherit_event(struct perf_event *parent_event, | |
10158 | struct task_struct *parent, | |
10159 | struct perf_event_context *parent_ctx, | |
10160 | struct task_struct *child, | |
10161 | struct perf_event *group_leader, | |
10162 | struct perf_event_context *child_ctx) | |
10163 | { | |
1929def9 | 10164 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10165 | struct perf_event *child_event; |
cee010ec | 10166 | unsigned long flags; |
97dee4f3 PZ |
10167 | |
10168 | /* | |
10169 | * Instead of creating recursive hierarchies of events, | |
10170 | * we link inherited events back to the original parent, | |
10171 | * which has a filp for sure, which we use as the reference | |
10172 | * count: | |
10173 | */ | |
10174 | if (parent_event->parent) | |
10175 | parent_event = parent_event->parent; | |
10176 | ||
10177 | child_event = perf_event_alloc(&parent_event->attr, | |
10178 | parent_event->cpu, | |
d580ff86 | 10179 | child, |
97dee4f3 | 10180 | group_leader, parent_event, |
79dff51e | 10181 | NULL, NULL, -1); |
97dee4f3 PZ |
10182 | if (IS_ERR(child_event)) |
10183 | return child_event; | |
a6fa941d | 10184 | |
c6e5b732 PZ |
10185 | /* |
10186 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10187 | * must be under the same lock in order to serialize against | |
10188 | * perf_event_release_kernel(), such that either we must observe | |
10189 | * is_orphaned_event() or they will observe us on the child_list. | |
10190 | */ | |
10191 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10192 | if (is_orphaned_event(parent_event) || |
10193 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10194 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10195 | free_event(child_event); |
10196 | return NULL; | |
10197 | } | |
10198 | ||
97dee4f3 PZ |
10199 | get_ctx(child_ctx); |
10200 | ||
10201 | /* | |
10202 | * Make the child state follow the state of the parent event, | |
10203 | * not its attr.disabled bit. We hold the parent's mutex, | |
10204 | * so we won't race with perf_event_{en, dis}able_family. | |
10205 | */ | |
1929def9 | 10206 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10207 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10208 | else | |
10209 | child_event->state = PERF_EVENT_STATE_OFF; | |
10210 | ||
10211 | if (parent_event->attr.freq) { | |
10212 | u64 sample_period = parent_event->hw.sample_period; | |
10213 | struct hw_perf_event *hwc = &child_event->hw; | |
10214 | ||
10215 | hwc->sample_period = sample_period; | |
10216 | hwc->last_period = sample_period; | |
10217 | ||
10218 | local64_set(&hwc->period_left, sample_period); | |
10219 | } | |
10220 | ||
10221 | child_event->ctx = child_ctx; | |
10222 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10223 | child_event->overflow_handler_context |
10224 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10225 | |
614b6780 TG |
10226 | /* |
10227 | * Precalculate sample_data sizes | |
10228 | */ | |
10229 | perf_event__header_size(child_event); | |
6844c09d | 10230 | perf_event__id_header_size(child_event); |
614b6780 | 10231 | |
97dee4f3 PZ |
10232 | /* |
10233 | * Link it up in the child's context: | |
10234 | */ | |
cee010ec | 10235 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10236 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10237 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10238 | |
97dee4f3 PZ |
10239 | /* |
10240 | * Link this into the parent event's child list | |
10241 | */ | |
97dee4f3 PZ |
10242 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10243 | mutex_unlock(&parent_event->child_mutex); | |
10244 | ||
10245 | return child_event; | |
10246 | } | |
10247 | ||
10248 | static int inherit_group(struct perf_event *parent_event, | |
10249 | struct task_struct *parent, | |
10250 | struct perf_event_context *parent_ctx, | |
10251 | struct task_struct *child, | |
10252 | struct perf_event_context *child_ctx) | |
10253 | { | |
10254 | struct perf_event *leader; | |
10255 | struct perf_event *sub; | |
10256 | struct perf_event *child_ctr; | |
10257 | ||
10258 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10259 | child, NULL, child_ctx); | |
10260 | if (IS_ERR(leader)) | |
10261 | return PTR_ERR(leader); | |
10262 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
10263 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10264 | child, leader, child_ctx); | |
10265 | if (IS_ERR(child_ctr)) | |
10266 | return PTR_ERR(child_ctr); | |
10267 | } | |
10268 | return 0; | |
889ff015 FW |
10269 | } |
10270 | ||
10271 | static int | |
10272 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10273 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10274 | struct task_struct *child, int ctxn, |
889ff015 FW |
10275 | int *inherited_all) |
10276 | { | |
10277 | int ret; | |
8dc85d54 | 10278 | struct perf_event_context *child_ctx; |
889ff015 FW |
10279 | |
10280 | if (!event->attr.inherit) { | |
10281 | *inherited_all = 0; | |
10282 | return 0; | |
bbbee908 PZ |
10283 | } |
10284 | ||
fe4b04fa | 10285 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10286 | if (!child_ctx) { |
10287 | /* | |
10288 | * This is executed from the parent task context, so | |
10289 | * inherit events that have been marked for cloning. | |
10290 | * First allocate and initialize a context for the | |
10291 | * child. | |
10292 | */ | |
bbbee908 | 10293 | |
734df5ab | 10294 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10295 | if (!child_ctx) |
10296 | return -ENOMEM; | |
bbbee908 | 10297 | |
8dc85d54 | 10298 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10299 | } |
10300 | ||
10301 | ret = inherit_group(event, parent, parent_ctx, | |
10302 | child, child_ctx); | |
10303 | ||
10304 | if (ret) | |
10305 | *inherited_all = 0; | |
10306 | ||
10307 | return ret; | |
bbbee908 PZ |
10308 | } |
10309 | ||
9b51f66d | 10310 | /* |
cdd6c482 | 10311 | * Initialize the perf_event context in task_struct |
9b51f66d | 10312 | */ |
985c8dcb | 10313 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10314 | { |
889ff015 | 10315 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10316 | struct perf_event_context *cloned_ctx; |
10317 | struct perf_event *event; | |
9b51f66d | 10318 | struct task_struct *parent = current; |
564c2b21 | 10319 | int inherited_all = 1; |
dddd3379 | 10320 | unsigned long flags; |
6ab423e0 | 10321 | int ret = 0; |
9b51f66d | 10322 | |
8dc85d54 | 10323 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10324 | return 0; |
10325 | ||
ad3a37de | 10326 | /* |
25346b93 PM |
10327 | * If the parent's context is a clone, pin it so it won't get |
10328 | * swapped under us. | |
ad3a37de | 10329 | */ |
8dc85d54 | 10330 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10331 | if (!parent_ctx) |
10332 | return 0; | |
25346b93 | 10333 | |
ad3a37de PM |
10334 | /* |
10335 | * No need to check if parent_ctx != NULL here; since we saw | |
10336 | * it non-NULL earlier, the only reason for it to become NULL | |
10337 | * is if we exit, and since we're currently in the middle of | |
10338 | * a fork we can't be exiting at the same time. | |
10339 | */ | |
ad3a37de | 10340 | |
9b51f66d IM |
10341 | /* |
10342 | * Lock the parent list. No need to lock the child - not PID | |
10343 | * hashed yet and not running, so nobody can access it. | |
10344 | */ | |
d859e29f | 10345 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10346 | |
10347 | /* | |
10348 | * We dont have to disable NMIs - we are only looking at | |
10349 | * the list, not manipulating it: | |
10350 | */ | |
889ff015 | 10351 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10352 | ret = inherit_task_group(event, parent, parent_ctx, |
10353 | child, ctxn, &inherited_all); | |
889ff015 FW |
10354 | if (ret) |
10355 | break; | |
10356 | } | |
b93f7978 | 10357 | |
dddd3379 TG |
10358 | /* |
10359 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10360 | * to allocations, but we need to prevent rotation because | |
10361 | * rotate_ctx() will change the list from interrupt context. | |
10362 | */ | |
10363 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10364 | parent_ctx->rotate_disable = 1; | |
10365 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10366 | ||
889ff015 | 10367 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10368 | ret = inherit_task_group(event, parent, parent_ctx, |
10369 | child, ctxn, &inherited_all); | |
889ff015 | 10370 | if (ret) |
9b51f66d | 10371 | break; |
564c2b21 PM |
10372 | } |
10373 | ||
dddd3379 TG |
10374 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10375 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10376 | |
8dc85d54 | 10377 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10378 | |
05cbaa28 | 10379 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10380 | /* |
10381 | * Mark the child context as a clone of the parent | |
10382 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10383 | * |
10384 | * Note that if the parent is a clone, the holding of | |
10385 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10386 | */ |
c5ed5145 | 10387 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10388 | if (cloned_ctx) { |
10389 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10390 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10391 | } else { |
10392 | child_ctx->parent_ctx = parent_ctx; | |
10393 | child_ctx->parent_gen = parent_ctx->generation; | |
10394 | } | |
10395 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10396 | } |
10397 | ||
c5ed5145 | 10398 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 10399 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10400 | |
25346b93 | 10401 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10402 | put_ctx(parent_ctx); |
ad3a37de | 10403 | |
6ab423e0 | 10404 | return ret; |
9b51f66d IM |
10405 | } |
10406 | ||
8dc85d54 PZ |
10407 | /* |
10408 | * Initialize the perf_event context in task_struct | |
10409 | */ | |
10410 | int perf_event_init_task(struct task_struct *child) | |
10411 | { | |
10412 | int ctxn, ret; | |
10413 | ||
8550d7cb ON |
10414 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10415 | mutex_init(&child->perf_event_mutex); | |
10416 | INIT_LIST_HEAD(&child->perf_event_list); | |
10417 | ||
8dc85d54 PZ |
10418 | for_each_task_context_nr(ctxn) { |
10419 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10420 | if (ret) { |
10421 | perf_event_free_task(child); | |
8dc85d54 | 10422 | return ret; |
6c72e350 | 10423 | } |
8dc85d54 PZ |
10424 | } |
10425 | ||
10426 | return 0; | |
10427 | } | |
10428 | ||
220b140b PM |
10429 | static void __init perf_event_init_all_cpus(void) |
10430 | { | |
b28ab83c | 10431 | struct swevent_htable *swhash; |
220b140b | 10432 | int cpu; |
220b140b PM |
10433 | |
10434 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10435 | swhash = &per_cpu(swevent_htable, cpu); |
10436 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10437 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10438 | |
10439 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10440 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 PZ |
10441 | |
10442 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); | |
220b140b PM |
10443 | } |
10444 | } | |
10445 | ||
00e16c3d | 10446 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10447 | { |
108b02cf | 10448 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10449 | |
b28ab83c | 10450 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10451 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10452 | struct swevent_hlist *hlist; |
10453 | ||
b28ab83c PZ |
10454 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10455 | WARN_ON(!hlist); | |
10456 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10457 | } |
b28ab83c | 10458 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10459 | return 0; |
0793a61d TG |
10460 | } |
10461 | ||
2965faa5 | 10462 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10463 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10464 | { |
108b02cf | 10465 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10466 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10467 | struct perf_event *event; | |
0793a61d | 10468 | |
fae3fde6 PZ |
10469 | raw_spin_lock(&ctx->lock); |
10470 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10471 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10472 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10473 | } |
108b02cf PZ |
10474 | |
10475 | static void perf_event_exit_cpu_context(int cpu) | |
10476 | { | |
10477 | struct perf_event_context *ctx; | |
10478 | struct pmu *pmu; | |
10479 | int idx; | |
10480 | ||
10481 | idx = srcu_read_lock(&pmus_srcu); | |
10482 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10483 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10484 | |
10485 | mutex_lock(&ctx->mutex); | |
10486 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10487 | mutex_unlock(&ctx->mutex); | |
10488 | } | |
10489 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10490 | } |
00e16c3d TG |
10491 | #else |
10492 | ||
10493 | static void perf_event_exit_cpu_context(int cpu) { } | |
10494 | ||
10495 | #endif | |
108b02cf | 10496 | |
00e16c3d | 10497 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10498 | { |
e3703f8c | 10499 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10500 | return 0; |
0793a61d | 10501 | } |
0793a61d | 10502 | |
c277443c PZ |
10503 | static int |
10504 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10505 | { | |
10506 | int cpu; | |
10507 | ||
10508 | for_each_online_cpu(cpu) | |
10509 | perf_event_exit_cpu(cpu); | |
10510 | ||
10511 | return NOTIFY_OK; | |
10512 | } | |
10513 | ||
10514 | /* | |
10515 | * Run the perf reboot notifier at the very last possible moment so that | |
10516 | * the generic watchdog code runs as long as possible. | |
10517 | */ | |
10518 | static struct notifier_block perf_reboot_notifier = { | |
10519 | .notifier_call = perf_reboot, | |
10520 | .priority = INT_MIN, | |
10521 | }; | |
10522 | ||
cdd6c482 | 10523 | void __init perf_event_init(void) |
0793a61d | 10524 | { |
3c502e7a JW |
10525 | int ret; |
10526 | ||
2e80a82a PZ |
10527 | idr_init(&pmu_idr); |
10528 | ||
220b140b | 10529 | perf_event_init_all_cpus(); |
b0a873eb | 10530 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
10531 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
10532 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
10533 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 10534 | perf_tp_register(); |
00e16c3d | 10535 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 10536 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
10537 | |
10538 | ret = init_hw_breakpoint(); | |
10539 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 10540 | |
b01c3a00 JO |
10541 | /* |
10542 | * Build time assertion that we keep the data_head at the intended | |
10543 | * location. IOW, validation we got the __reserved[] size right. | |
10544 | */ | |
10545 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
10546 | != 1024); | |
0793a61d | 10547 | } |
abe43400 | 10548 | |
fd979c01 CS |
10549 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
10550 | char *page) | |
10551 | { | |
10552 | struct perf_pmu_events_attr *pmu_attr = | |
10553 | container_of(attr, struct perf_pmu_events_attr, attr); | |
10554 | ||
10555 | if (pmu_attr->event_str) | |
10556 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
10557 | ||
10558 | return 0; | |
10559 | } | |
675965b0 | 10560 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 10561 | |
abe43400 PZ |
10562 | static int __init perf_event_sysfs_init(void) |
10563 | { | |
10564 | struct pmu *pmu; | |
10565 | int ret; | |
10566 | ||
10567 | mutex_lock(&pmus_lock); | |
10568 | ||
10569 | ret = bus_register(&pmu_bus); | |
10570 | if (ret) | |
10571 | goto unlock; | |
10572 | ||
10573 | list_for_each_entry(pmu, &pmus, entry) { | |
10574 | if (!pmu->name || pmu->type < 0) | |
10575 | continue; | |
10576 | ||
10577 | ret = pmu_dev_alloc(pmu); | |
10578 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
10579 | } | |
10580 | pmu_bus_running = 1; | |
10581 | ret = 0; | |
10582 | ||
10583 | unlock: | |
10584 | mutex_unlock(&pmus_lock); | |
10585 | ||
10586 | return ret; | |
10587 | } | |
10588 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
10589 | |
10590 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
10591 | static struct cgroup_subsys_state * |
10592 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
10593 | { |
10594 | struct perf_cgroup *jc; | |
e5d1367f | 10595 | |
1b15d055 | 10596 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
10597 | if (!jc) |
10598 | return ERR_PTR(-ENOMEM); | |
10599 | ||
e5d1367f SE |
10600 | jc->info = alloc_percpu(struct perf_cgroup_info); |
10601 | if (!jc->info) { | |
10602 | kfree(jc); | |
10603 | return ERR_PTR(-ENOMEM); | |
10604 | } | |
10605 | ||
e5d1367f SE |
10606 | return &jc->css; |
10607 | } | |
10608 | ||
eb95419b | 10609 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 10610 | { |
eb95419b TH |
10611 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
10612 | ||
e5d1367f SE |
10613 | free_percpu(jc->info); |
10614 | kfree(jc); | |
10615 | } | |
10616 | ||
10617 | static int __perf_cgroup_move(void *info) | |
10618 | { | |
10619 | struct task_struct *task = info; | |
ddaaf4e2 | 10620 | rcu_read_lock(); |
e5d1367f | 10621 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 10622 | rcu_read_unlock(); |
e5d1367f SE |
10623 | return 0; |
10624 | } | |
10625 | ||
1f7dd3e5 | 10626 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 10627 | { |
bb9d97b6 | 10628 | struct task_struct *task; |
1f7dd3e5 | 10629 | struct cgroup_subsys_state *css; |
bb9d97b6 | 10630 | |
1f7dd3e5 | 10631 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 10632 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
10633 | } |
10634 | ||
073219e9 | 10635 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
10636 | .css_alloc = perf_cgroup_css_alloc, |
10637 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 10638 | .attach = perf_cgroup_attach, |
e5d1367f SE |
10639 | }; |
10640 | #endif /* CONFIG_CGROUP_PERF */ |