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Commit | Line | Data |
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8e86e015 | 1 | // SPDX-License-Identifier: GPL-2.0 |
0793a61d | 2 | /* |
57c0c15b | 3 | * Performance events core code: |
0793a61d | 4 | * |
98144511 | 5 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 7 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 8 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
0793a61d TG |
9 | */ |
10 | ||
11 | #include <linux/fs.h> | |
b9cacc7b | 12 | #include <linux/mm.h> |
0793a61d TG |
13 | #include <linux/cpu.h> |
14 | #include <linux/smp.h> | |
2e80a82a | 15 | #include <linux/idr.h> |
04289bb9 | 16 | #include <linux/file.h> |
0793a61d | 17 | #include <linux/poll.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
76e1d904 | 19 | #include <linux/hash.h> |
12351ef8 | 20 | #include <linux/tick.h> |
0793a61d | 21 | #include <linux/sysfs.h> |
22a4f650 | 22 | #include <linux/dcache.h> |
0793a61d | 23 | #include <linux/percpu.h> |
22a4f650 | 24 | #include <linux/ptrace.h> |
c277443c | 25 | #include <linux/reboot.h> |
b9cacc7b | 26 | #include <linux/vmstat.h> |
abe43400 | 27 | #include <linux/device.h> |
6e5fdeed | 28 | #include <linux/export.h> |
906010b2 | 29 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
30 | #include <linux/hardirq.h> |
31 | #include <linux/rculist.h> | |
0793a61d TG |
32 | #include <linux/uaccess.h> |
33 | #include <linux/syscalls.h> | |
34 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 35 | #include <linux/kernel_stat.h> |
39bed6cb | 36 | #include <linux/cgroup.h> |
cdd6c482 | 37 | #include <linux/perf_event.h> |
af658dca | 38 | #include <linux/trace_events.h> |
3c502e7a | 39 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 40 | #include <linux/mm_types.h> |
c464c76e | 41 | #include <linux/module.h> |
f972eb63 | 42 | #include <linux/mman.h> |
b3f20785 | 43 | #include <linux/compat.h> |
2541517c AS |
44 | #include <linux/bpf.h> |
45 | #include <linux/filter.h> | |
375637bc AS |
46 | #include <linux/namei.h> |
47 | #include <linux/parser.h> | |
e6017571 | 48 | #include <linux/sched/clock.h> |
6e84f315 | 49 | #include <linux/sched/mm.h> |
e4222673 HB |
50 | #include <linux/proc_ns.h> |
51 | #include <linux/mount.h> | |
6eef8a71 | 52 | #include <linux/min_heap.h> |
0793a61d | 53 | |
76369139 FW |
54 | #include "internal.h" |
55 | ||
4e193bd4 TB |
56 | #include <asm/irq_regs.h> |
57 | ||
272325c4 PZ |
58 | typedef int (*remote_function_f)(void *); |
59 | ||
fe4b04fa | 60 | struct remote_function_call { |
e7e7ee2e | 61 | struct task_struct *p; |
272325c4 | 62 | remote_function_f func; |
e7e7ee2e IM |
63 | void *info; |
64 | int ret; | |
fe4b04fa PZ |
65 | }; |
66 | ||
67 | static void remote_function(void *data) | |
68 | { | |
69 | struct remote_function_call *tfc = data; | |
70 | struct task_struct *p = tfc->p; | |
71 | ||
72 | if (p) { | |
0da4cf3e PZ |
73 | /* -EAGAIN */ |
74 | if (task_cpu(p) != smp_processor_id()) | |
75 | return; | |
76 | ||
77 | /* | |
78 | * Now that we're on right CPU with IRQs disabled, we can test | |
79 | * if we hit the right task without races. | |
80 | */ | |
81 | ||
82 | tfc->ret = -ESRCH; /* No such (running) process */ | |
83 | if (p != current) | |
fe4b04fa PZ |
84 | return; |
85 | } | |
86 | ||
87 | tfc->ret = tfc->func(tfc->info); | |
88 | } | |
89 | ||
90 | /** | |
91 | * task_function_call - call a function on the cpu on which a task runs | |
92 | * @p: the task to evaluate | |
93 | * @func: the function to be called | |
94 | * @info: the function call argument | |
95 | * | |
96 | * Calls the function @func when the task is currently running. This might | |
97 | * be on the current CPU, which just calls the function directly | |
98 | * | |
99 | * returns: @func return value, or | |
100 | * -ESRCH - when the process isn't running | |
101 | * -EAGAIN - when the process moved away | |
102 | */ | |
103 | static int | |
272325c4 | 104 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
105 | { |
106 | struct remote_function_call data = { | |
e7e7ee2e IM |
107 | .p = p, |
108 | .func = func, | |
109 | .info = info, | |
0da4cf3e | 110 | .ret = -EAGAIN, |
fe4b04fa | 111 | }; |
0da4cf3e | 112 | int ret; |
fe4b04fa | 113 | |
0da4cf3e PZ |
114 | do { |
115 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
116 | if (!ret) | |
117 | ret = data.ret; | |
118 | } while (ret == -EAGAIN); | |
fe4b04fa | 119 | |
0da4cf3e | 120 | return ret; |
fe4b04fa PZ |
121 | } |
122 | ||
123 | /** | |
124 | * cpu_function_call - call a function on the cpu | |
125 | * @func: the function to be called | |
126 | * @info: the function call argument | |
127 | * | |
128 | * Calls the function @func on the remote cpu. | |
129 | * | |
130 | * returns: @func return value or -ENXIO when the cpu is offline | |
131 | */ | |
272325c4 | 132 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
133 | { |
134 | struct remote_function_call data = { | |
e7e7ee2e IM |
135 | .p = NULL, |
136 | .func = func, | |
137 | .info = info, | |
138 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
139 | }; |
140 | ||
141 | smp_call_function_single(cpu, remote_function, &data, 1); | |
142 | ||
143 | return data.ret; | |
144 | } | |
145 | ||
fae3fde6 PZ |
146 | static inline struct perf_cpu_context * |
147 | __get_cpu_context(struct perf_event_context *ctx) | |
148 | { | |
149 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
150 | } | |
151 | ||
152 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
153 | struct perf_event_context *ctx) | |
0017960f | 154 | { |
fae3fde6 PZ |
155 | raw_spin_lock(&cpuctx->ctx.lock); |
156 | if (ctx) | |
157 | raw_spin_lock(&ctx->lock); | |
158 | } | |
159 | ||
160 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
161 | struct perf_event_context *ctx) | |
162 | { | |
163 | if (ctx) | |
164 | raw_spin_unlock(&ctx->lock); | |
165 | raw_spin_unlock(&cpuctx->ctx.lock); | |
166 | } | |
167 | ||
63b6da39 PZ |
168 | #define TASK_TOMBSTONE ((void *)-1L) |
169 | ||
170 | static bool is_kernel_event(struct perf_event *event) | |
171 | { | |
f47c02c0 | 172 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
173 | } |
174 | ||
39a43640 PZ |
175 | /* |
176 | * On task ctx scheduling... | |
177 | * | |
178 | * When !ctx->nr_events a task context will not be scheduled. This means | |
179 | * we can disable the scheduler hooks (for performance) without leaving | |
180 | * pending task ctx state. | |
181 | * | |
182 | * This however results in two special cases: | |
183 | * | |
184 | * - removing the last event from a task ctx; this is relatively straight | |
185 | * forward and is done in __perf_remove_from_context. | |
186 | * | |
187 | * - adding the first event to a task ctx; this is tricky because we cannot | |
188 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
189 | * See perf_install_in_context(). | |
190 | * | |
39a43640 PZ |
191 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
192 | */ | |
193 | ||
fae3fde6 PZ |
194 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
195 | struct perf_event_context *, void *); | |
196 | ||
197 | struct event_function_struct { | |
198 | struct perf_event *event; | |
199 | event_f func; | |
200 | void *data; | |
201 | }; | |
202 | ||
203 | static int event_function(void *info) | |
204 | { | |
205 | struct event_function_struct *efs = info; | |
206 | struct perf_event *event = efs->event; | |
0017960f | 207 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
208 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
209 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 210 | int ret = 0; |
fae3fde6 | 211 | |
16444645 | 212 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 213 | |
63b6da39 | 214 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
215 | /* |
216 | * Since we do the IPI call without holding ctx->lock things can have | |
217 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
218 | */ |
219 | if (ctx->task) { | |
63b6da39 | 220 | if (ctx->task != current) { |
0da4cf3e | 221 | ret = -ESRCH; |
63b6da39 PZ |
222 | goto unlock; |
223 | } | |
fae3fde6 | 224 | |
fae3fde6 PZ |
225 | /* |
226 | * We only use event_function_call() on established contexts, | |
227 | * and event_function() is only ever called when active (or | |
228 | * rather, we'll have bailed in task_function_call() or the | |
229 | * above ctx->task != current test), therefore we must have | |
230 | * ctx->is_active here. | |
231 | */ | |
232 | WARN_ON_ONCE(!ctx->is_active); | |
233 | /* | |
234 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
235 | * match. | |
236 | */ | |
63b6da39 PZ |
237 | WARN_ON_ONCE(task_ctx != ctx); |
238 | } else { | |
239 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 240 | } |
63b6da39 | 241 | |
fae3fde6 | 242 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 243 | unlock: |
fae3fde6 PZ |
244 | perf_ctx_unlock(cpuctx, task_ctx); |
245 | ||
63b6da39 | 246 | return ret; |
fae3fde6 PZ |
247 | } |
248 | ||
fae3fde6 | 249 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
250 | { |
251 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 252 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
253 | struct event_function_struct efs = { |
254 | .event = event, | |
255 | .func = func, | |
256 | .data = data, | |
257 | }; | |
0017960f | 258 | |
c97f4736 PZ |
259 | if (!event->parent) { |
260 | /* | |
261 | * If this is a !child event, we must hold ctx::mutex to | |
262 | * stabilize the the event->ctx relation. See | |
263 | * perf_event_ctx_lock(). | |
264 | */ | |
265 | lockdep_assert_held(&ctx->mutex); | |
266 | } | |
0017960f PZ |
267 | |
268 | if (!task) { | |
fae3fde6 | 269 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
270 | return; |
271 | } | |
272 | ||
63b6da39 PZ |
273 | if (task == TASK_TOMBSTONE) |
274 | return; | |
275 | ||
a096309b | 276 | again: |
fae3fde6 | 277 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
278 | return; |
279 | ||
280 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
281 | /* |
282 | * Reload the task pointer, it might have been changed by | |
283 | * a concurrent perf_event_context_sched_out(). | |
284 | */ | |
285 | task = ctx->task; | |
a096309b PZ |
286 | if (task == TASK_TOMBSTONE) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | return; | |
0017960f | 289 | } |
a096309b PZ |
290 | if (ctx->is_active) { |
291 | raw_spin_unlock_irq(&ctx->lock); | |
292 | goto again; | |
293 | } | |
294 | func(event, NULL, ctx, data); | |
0017960f PZ |
295 | raw_spin_unlock_irq(&ctx->lock); |
296 | } | |
297 | ||
cca20946 PZ |
298 | /* |
299 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
300 | * are already disabled and we're on the right CPU. | |
301 | */ | |
302 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
303 | { | |
304 | struct perf_event_context *ctx = event->ctx; | |
305 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
306 | struct task_struct *task = READ_ONCE(ctx->task); | |
307 | struct perf_event_context *task_ctx = NULL; | |
308 | ||
16444645 | 309 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
310 | |
311 | if (task) { | |
312 | if (task == TASK_TOMBSTONE) | |
313 | return; | |
314 | ||
315 | task_ctx = ctx; | |
316 | } | |
317 | ||
318 | perf_ctx_lock(cpuctx, task_ctx); | |
319 | ||
320 | task = ctx->task; | |
321 | if (task == TASK_TOMBSTONE) | |
322 | goto unlock; | |
323 | ||
324 | if (task) { | |
325 | /* | |
326 | * We must be either inactive or active and the right task, | |
327 | * otherwise we're screwed, since we cannot IPI to somewhere | |
328 | * else. | |
329 | */ | |
330 | if (ctx->is_active) { | |
331 | if (WARN_ON_ONCE(task != current)) | |
332 | goto unlock; | |
333 | ||
334 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
335 | goto unlock; | |
336 | } | |
337 | } else { | |
338 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
339 | } | |
340 | ||
341 | func(event, cpuctx, ctx, data); | |
342 | unlock: | |
343 | perf_ctx_unlock(cpuctx, task_ctx); | |
344 | } | |
345 | ||
e5d1367f SE |
346 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
347 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
348 | PERF_FLAG_PID_CGROUP |\ |
349 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 350 | |
bce38cd5 SE |
351 | /* |
352 | * branch priv levels that need permission checks | |
353 | */ | |
354 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
355 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
356 | PERF_SAMPLE_BRANCH_HV) | |
357 | ||
0b3fcf17 SE |
358 | enum event_type_t { |
359 | EVENT_FLEXIBLE = 0x1, | |
360 | EVENT_PINNED = 0x2, | |
3cbaa590 | 361 | EVENT_TIME = 0x4, |
487f05e1 AS |
362 | /* see ctx_resched() for details */ |
363 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
364 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
365 | }; | |
366 | ||
e5d1367f SE |
367 | /* |
368 | * perf_sched_events : >0 events exist | |
369 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
370 | */ | |
9107c89e PZ |
371 | |
372 | static void perf_sched_delayed(struct work_struct *work); | |
373 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
374 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
375 | static DEFINE_MUTEX(perf_sched_mutex); | |
376 | static atomic_t perf_sched_count; | |
377 | ||
e5d1367f | 378 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 379 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 380 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 381 | |
cdd6c482 IM |
382 | static atomic_t nr_mmap_events __read_mostly; |
383 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 384 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 385 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 386 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 387 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 388 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 389 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 390 | static atomic_t nr_cgroup_events __read_mostly; |
9ee318a7 | 391 | |
108b02cf PZ |
392 | static LIST_HEAD(pmus); |
393 | static DEFINE_MUTEX(pmus_lock); | |
394 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 395 | static cpumask_var_t perf_online_mask; |
108b02cf | 396 | |
0764771d | 397 | /* |
cdd6c482 | 398 | * perf event paranoia level: |
0fbdea19 IM |
399 | * -1 - not paranoid at all |
400 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 401 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 402 | * 2 - disallow kernel profiling for unpriv |
0764771d | 403 | */ |
0161028b | 404 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 405 | |
20443384 FW |
406 | /* Minimum for 512 kiB + 1 user control page */ |
407 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
408 | |
409 | /* | |
cdd6c482 | 410 | * max perf event sample rate |
df58ab24 | 411 | */ |
14c63f17 DH |
412 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
413 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
414 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
415 | ||
416 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
417 | ||
418 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
419 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
420 | ||
d9494cb4 PZ |
421 | static int perf_sample_allowed_ns __read_mostly = |
422 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 423 | |
18ab2cd3 | 424 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
425 | { |
426 | u64 tmp = perf_sample_period_ns; | |
427 | ||
428 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
429 | tmp = div_u64(tmp, 100); |
430 | if (!tmp) | |
431 | tmp = 1; | |
432 | ||
433 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 434 | } |
163ec435 | 435 | |
8d5bce0c | 436 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 437 | |
163ec435 PZ |
438 | int perf_proc_update_handler(struct ctl_table *table, int write, |
439 | void __user *buffer, size_t *lenp, | |
440 | loff_t *ppos) | |
441 | { | |
1a51c5da SE |
442 | int ret; |
443 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
444 | /* |
445 | * If throttling is disabled don't allow the write: | |
446 | */ | |
1a51c5da | 447 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
448 | return -EINVAL; |
449 | ||
1a51c5da SE |
450 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
451 | if (ret || !write) | |
452 | return ret; | |
453 | ||
163ec435 | 454 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
455 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
456 | update_perf_cpu_limits(); | |
457 | ||
458 | return 0; | |
459 | } | |
460 | ||
461 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
462 | ||
463 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
464 | void __user *buffer, size_t *lenp, | |
465 | loff_t *ppos) | |
466 | { | |
1572e45a | 467 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
468 | |
469 | if (ret || !write) | |
470 | return ret; | |
471 | ||
b303e7c1 PZ |
472 | if (sysctl_perf_cpu_time_max_percent == 100 || |
473 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
474 | printk(KERN_WARNING |
475 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
476 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
477 | } else { | |
478 | update_perf_cpu_limits(); | |
479 | } | |
163ec435 PZ |
480 | |
481 | return 0; | |
482 | } | |
1ccd1549 | 483 | |
14c63f17 DH |
484 | /* |
485 | * perf samples are done in some very critical code paths (NMIs). | |
486 | * If they take too much CPU time, the system can lock up and not | |
487 | * get any real work done. This will drop the sample rate when | |
488 | * we detect that events are taking too long. | |
489 | */ | |
490 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 491 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 492 | |
91a612ee PZ |
493 | static u64 __report_avg; |
494 | static u64 __report_allowed; | |
495 | ||
6a02ad66 | 496 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 497 | { |
0d87d7ec | 498 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
499 | "perf: interrupt took too long (%lld > %lld), lowering " |
500 | "kernel.perf_event_max_sample_rate to %d\n", | |
501 | __report_avg, __report_allowed, | |
502 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
503 | } |
504 | ||
505 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
506 | ||
507 | void perf_sample_event_took(u64 sample_len_ns) | |
508 | { | |
91a612ee PZ |
509 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
510 | u64 running_len; | |
511 | u64 avg_len; | |
512 | u32 max; | |
14c63f17 | 513 | |
91a612ee | 514 | if (max_len == 0) |
14c63f17 DH |
515 | return; |
516 | ||
91a612ee PZ |
517 | /* Decay the counter by 1 average sample. */ |
518 | running_len = __this_cpu_read(running_sample_length); | |
519 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
520 | running_len += sample_len_ns; | |
521 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
522 | |
523 | /* | |
91a612ee PZ |
524 | * Note: this will be biased artifically low until we have |
525 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
526 | * from having to maintain a count. |
527 | */ | |
91a612ee PZ |
528 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
529 | if (avg_len <= max_len) | |
14c63f17 DH |
530 | return; |
531 | ||
91a612ee PZ |
532 | __report_avg = avg_len; |
533 | __report_allowed = max_len; | |
14c63f17 | 534 | |
91a612ee PZ |
535 | /* |
536 | * Compute a throttle threshold 25% below the current duration. | |
537 | */ | |
538 | avg_len += avg_len / 4; | |
539 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
540 | if (avg_len < max) | |
541 | max /= (u32)avg_len; | |
542 | else | |
543 | max = 1; | |
14c63f17 | 544 | |
91a612ee PZ |
545 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
546 | WRITE_ONCE(max_samples_per_tick, max); | |
547 | ||
548 | sysctl_perf_event_sample_rate = max * HZ; | |
549 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 550 | |
cd578abb | 551 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 552 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 553 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 554 | __report_avg, __report_allowed, |
cd578abb PZ |
555 | sysctl_perf_event_sample_rate); |
556 | } | |
14c63f17 DH |
557 | } |
558 | ||
cdd6c482 | 559 | static atomic64_t perf_event_id; |
a96bbc16 | 560 | |
0b3fcf17 SE |
561 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
562 | enum event_type_t event_type); | |
563 | ||
564 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
565 | enum event_type_t event_type, |
566 | struct task_struct *task); | |
567 | ||
568 | static void update_context_time(struct perf_event_context *ctx); | |
569 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 570 | |
cdd6c482 | 571 | void __weak perf_event_print_debug(void) { } |
0793a61d | 572 | |
84c79910 | 573 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 574 | { |
84c79910 | 575 | return "pmu"; |
0793a61d TG |
576 | } |
577 | ||
0b3fcf17 SE |
578 | static inline u64 perf_clock(void) |
579 | { | |
580 | return local_clock(); | |
581 | } | |
582 | ||
34f43927 PZ |
583 | static inline u64 perf_event_clock(struct perf_event *event) |
584 | { | |
585 | return event->clock(); | |
586 | } | |
587 | ||
0d3d73aa PZ |
588 | /* |
589 | * State based event timekeeping... | |
590 | * | |
591 | * The basic idea is to use event->state to determine which (if any) time | |
592 | * fields to increment with the current delta. This means we only need to | |
593 | * update timestamps when we change state or when they are explicitly requested | |
594 | * (read). | |
595 | * | |
596 | * Event groups make things a little more complicated, but not terribly so. The | |
597 | * rules for a group are that if the group leader is OFF the entire group is | |
598 | * OFF, irrespecive of what the group member states are. This results in | |
599 | * __perf_effective_state(). | |
600 | * | |
601 | * A futher ramification is that when a group leader flips between OFF and | |
602 | * !OFF, we need to update all group member times. | |
603 | * | |
604 | * | |
605 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
606 | * need to make sure the relevant context time is updated before we try and | |
607 | * update our timestamps. | |
608 | */ | |
609 | ||
610 | static __always_inline enum perf_event_state | |
611 | __perf_effective_state(struct perf_event *event) | |
612 | { | |
613 | struct perf_event *leader = event->group_leader; | |
614 | ||
615 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
616 | return leader->state; | |
617 | ||
618 | return event->state; | |
619 | } | |
620 | ||
621 | static __always_inline void | |
622 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
623 | { | |
624 | enum perf_event_state state = __perf_effective_state(event); | |
625 | u64 delta = now - event->tstamp; | |
626 | ||
627 | *enabled = event->total_time_enabled; | |
628 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
629 | *enabled += delta; | |
630 | ||
631 | *running = event->total_time_running; | |
632 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
633 | *running += delta; | |
634 | } | |
635 | ||
636 | static void perf_event_update_time(struct perf_event *event) | |
637 | { | |
638 | u64 now = perf_event_time(event); | |
639 | ||
640 | __perf_update_times(event, now, &event->total_time_enabled, | |
641 | &event->total_time_running); | |
642 | event->tstamp = now; | |
643 | } | |
644 | ||
645 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
646 | { | |
647 | struct perf_event *sibling; | |
648 | ||
edb39592 | 649 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
650 | perf_event_update_time(sibling); |
651 | } | |
652 | ||
653 | static void | |
654 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
655 | { | |
656 | if (event->state == state) | |
657 | return; | |
658 | ||
659 | perf_event_update_time(event); | |
660 | /* | |
661 | * If a group leader gets enabled/disabled all its siblings | |
662 | * are affected too. | |
663 | */ | |
664 | if ((event->state < 0) ^ (state < 0)) | |
665 | perf_event_update_sibling_time(event); | |
666 | ||
667 | WRITE_ONCE(event->state, state); | |
668 | } | |
669 | ||
e5d1367f SE |
670 | #ifdef CONFIG_CGROUP_PERF |
671 | ||
e5d1367f SE |
672 | static inline bool |
673 | perf_cgroup_match(struct perf_event *event) | |
674 | { | |
675 | struct perf_event_context *ctx = event->ctx; | |
676 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
677 | ||
ef824fa1 TH |
678 | /* @event doesn't care about cgroup */ |
679 | if (!event->cgrp) | |
680 | return true; | |
681 | ||
682 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
683 | if (!cpuctx->cgrp) | |
684 | return false; | |
685 | ||
686 | /* | |
687 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
688 | * also enabled for all its descendant cgroups. If @cpuctx's | |
689 | * cgroup is a descendant of @event's (the test covers identity | |
690 | * case), it's a match. | |
691 | */ | |
692 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
693 | event->cgrp->css.cgroup); | |
e5d1367f SE |
694 | } |
695 | ||
e5d1367f SE |
696 | static inline void perf_detach_cgroup(struct perf_event *event) |
697 | { | |
4e2ba650 | 698 | css_put(&event->cgrp->css); |
e5d1367f SE |
699 | event->cgrp = NULL; |
700 | } | |
701 | ||
702 | static inline int is_cgroup_event(struct perf_event *event) | |
703 | { | |
704 | return event->cgrp != NULL; | |
705 | } | |
706 | ||
707 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
708 | { | |
709 | struct perf_cgroup_info *t; | |
710 | ||
711 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
712 | return t->time; | |
713 | } | |
714 | ||
715 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
716 | { | |
717 | struct perf_cgroup_info *info; | |
718 | u64 now; | |
719 | ||
720 | now = perf_clock(); | |
721 | ||
722 | info = this_cpu_ptr(cgrp->info); | |
723 | ||
724 | info->time += now - info->timestamp; | |
725 | info->timestamp = now; | |
726 | } | |
727 | ||
728 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
729 | { | |
c917e0f2 SL |
730 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
731 | struct cgroup_subsys_state *css; | |
732 | ||
733 | if (cgrp) { | |
734 | for (css = &cgrp->css; css; css = css->parent) { | |
735 | cgrp = container_of(css, struct perf_cgroup, css); | |
736 | __update_cgrp_time(cgrp); | |
737 | } | |
738 | } | |
e5d1367f SE |
739 | } |
740 | ||
741 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
742 | { | |
3f7cce3c SE |
743 | struct perf_cgroup *cgrp; |
744 | ||
e5d1367f | 745 | /* |
3f7cce3c SE |
746 | * ensure we access cgroup data only when needed and |
747 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 748 | */ |
3f7cce3c | 749 | if (!is_cgroup_event(event)) |
e5d1367f SE |
750 | return; |
751 | ||
614e4c4e | 752 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
753 | /* |
754 | * Do not update time when cgroup is not active | |
755 | */ | |
28fa741c | 756 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 757 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
758 | } |
759 | ||
760 | static inline void | |
3f7cce3c SE |
761 | perf_cgroup_set_timestamp(struct task_struct *task, |
762 | struct perf_event_context *ctx) | |
e5d1367f SE |
763 | { |
764 | struct perf_cgroup *cgrp; | |
765 | struct perf_cgroup_info *info; | |
c917e0f2 | 766 | struct cgroup_subsys_state *css; |
e5d1367f | 767 | |
3f7cce3c SE |
768 | /* |
769 | * ctx->lock held by caller | |
770 | * ensure we do not access cgroup data | |
771 | * unless we have the cgroup pinned (css_get) | |
772 | */ | |
773 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
774 | return; |
775 | ||
614e4c4e | 776 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
777 | |
778 | for (css = &cgrp->css; css; css = css->parent) { | |
779 | cgrp = container_of(css, struct perf_cgroup, css); | |
780 | info = this_cpu_ptr(cgrp->info); | |
781 | info->timestamp = ctx->timestamp; | |
782 | } | |
e5d1367f SE |
783 | } |
784 | ||
058fe1c0 DCC |
785 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
786 | ||
e5d1367f SE |
787 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
788 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
789 | ||
790 | /* | |
791 | * reschedule events based on the cgroup constraint of task. | |
792 | * | |
793 | * mode SWOUT : schedule out everything | |
794 | * mode SWIN : schedule in based on cgroup for next | |
795 | */ | |
18ab2cd3 | 796 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
797 | { |
798 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 799 | struct list_head *list; |
e5d1367f SE |
800 | unsigned long flags; |
801 | ||
802 | /* | |
058fe1c0 DCC |
803 | * Disable interrupts and preemption to avoid this CPU's |
804 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
805 | */ |
806 | local_irq_save(flags); | |
807 | ||
058fe1c0 DCC |
808 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
809 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
810 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 811 | |
058fe1c0 DCC |
812 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
813 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 814 | |
058fe1c0 DCC |
815 | if (mode & PERF_CGROUP_SWOUT) { |
816 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
817 | /* | |
818 | * must not be done before ctxswout due | |
819 | * to event_filter_match() in event_sched_out() | |
820 | */ | |
821 | cpuctx->cgrp = NULL; | |
822 | } | |
e5d1367f | 823 | |
058fe1c0 DCC |
824 | if (mode & PERF_CGROUP_SWIN) { |
825 | WARN_ON_ONCE(cpuctx->cgrp); | |
826 | /* | |
827 | * set cgrp before ctxsw in to allow | |
828 | * event_filter_match() to not have to pass | |
829 | * task around | |
830 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
831 | * because cgorup events are only per-cpu | |
832 | */ | |
833 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
834 | &cpuctx->ctx); | |
835 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 836 | } |
058fe1c0 DCC |
837 | perf_pmu_enable(cpuctx->ctx.pmu); |
838 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
839 | } |
840 | ||
e5d1367f SE |
841 | local_irq_restore(flags); |
842 | } | |
843 | ||
a8d757ef SE |
844 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
845 | struct task_struct *next) | |
e5d1367f | 846 | { |
a8d757ef SE |
847 | struct perf_cgroup *cgrp1; |
848 | struct perf_cgroup *cgrp2 = NULL; | |
849 | ||
ddaaf4e2 | 850 | rcu_read_lock(); |
a8d757ef SE |
851 | /* |
852 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
853 | * we do not need to pass the ctx here because we know |
854 | * we are holding the rcu lock | |
a8d757ef | 855 | */ |
614e4c4e | 856 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 857 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
858 | |
859 | /* | |
860 | * only schedule out current cgroup events if we know | |
861 | * that we are switching to a different cgroup. Otherwise, | |
862 | * do no touch the cgroup events. | |
863 | */ | |
864 | if (cgrp1 != cgrp2) | |
865 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
866 | |
867 | rcu_read_unlock(); | |
e5d1367f SE |
868 | } |
869 | ||
a8d757ef SE |
870 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
871 | struct task_struct *task) | |
e5d1367f | 872 | { |
a8d757ef SE |
873 | struct perf_cgroup *cgrp1; |
874 | struct perf_cgroup *cgrp2 = NULL; | |
875 | ||
ddaaf4e2 | 876 | rcu_read_lock(); |
a8d757ef SE |
877 | /* |
878 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
879 | * we do not need to pass the ctx here because we know |
880 | * we are holding the rcu lock | |
a8d757ef | 881 | */ |
614e4c4e | 882 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 883 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
884 | |
885 | /* | |
886 | * only need to schedule in cgroup events if we are changing | |
887 | * cgroup during ctxsw. Cgroup events were not scheduled | |
888 | * out of ctxsw out if that was not the case. | |
889 | */ | |
890 | if (cgrp1 != cgrp2) | |
891 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
892 | |
893 | rcu_read_unlock(); | |
e5d1367f SE |
894 | } |
895 | ||
c2283c93 IR |
896 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
897 | struct cgroup_subsys_state *css) | |
898 | { | |
899 | struct perf_cpu_context *cpuctx; | |
900 | struct perf_event **storage; | |
901 | int cpu, heap_size, ret = 0; | |
902 | ||
903 | /* | |
904 | * Allow storage to have sufficent space for an iterator for each | |
905 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
906 | */ | |
907 | for (heap_size = 1; css; css = css->parent) | |
908 | heap_size++; | |
909 | ||
910 | for_each_possible_cpu(cpu) { | |
911 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
912 | if (heap_size <= cpuctx->heap_size) | |
913 | continue; | |
914 | ||
915 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
916 | GFP_KERNEL, cpu_to_node(cpu)); | |
917 | if (!storage) { | |
918 | ret = -ENOMEM; | |
919 | break; | |
920 | } | |
921 | ||
922 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
923 | if (cpuctx->heap_size < heap_size) { | |
924 | swap(cpuctx->heap, storage); | |
925 | if (storage == cpuctx->heap_default) | |
926 | storage = NULL; | |
927 | cpuctx->heap_size = heap_size; | |
928 | } | |
929 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
930 | ||
931 | kfree(storage); | |
932 | } | |
933 | ||
934 | return ret; | |
935 | } | |
936 | ||
e5d1367f SE |
937 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
938 | struct perf_event_attr *attr, | |
939 | struct perf_event *group_leader) | |
940 | { | |
941 | struct perf_cgroup *cgrp; | |
942 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
943 | struct fd f = fdget(fd); |
944 | int ret = 0; | |
e5d1367f | 945 | |
2903ff01 | 946 | if (!f.file) |
e5d1367f SE |
947 | return -EBADF; |
948 | ||
b583043e | 949 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 950 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
951 | if (IS_ERR(css)) { |
952 | ret = PTR_ERR(css); | |
953 | goto out; | |
954 | } | |
e5d1367f | 955 | |
c2283c93 IR |
956 | ret = perf_cgroup_ensure_storage(event, css); |
957 | if (ret) | |
958 | goto out; | |
959 | ||
e5d1367f SE |
960 | cgrp = container_of(css, struct perf_cgroup, css); |
961 | event->cgrp = cgrp; | |
962 | ||
963 | /* | |
964 | * all events in a group must monitor | |
965 | * the same cgroup because a task belongs | |
966 | * to only one perf cgroup at a time | |
967 | */ | |
968 | if (group_leader && group_leader->cgrp != cgrp) { | |
969 | perf_detach_cgroup(event); | |
970 | ret = -EINVAL; | |
e5d1367f | 971 | } |
3db272c0 | 972 | out: |
2903ff01 | 973 | fdput(f); |
e5d1367f SE |
974 | return ret; |
975 | } | |
976 | ||
977 | static inline void | |
978 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
979 | { | |
980 | struct perf_cgroup_info *t; | |
981 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
982 | event->shadow_ctx_time = now - t->timestamp; | |
983 | } | |
984 | ||
db4a8356 DCC |
985 | /* |
986 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
987 | * cleared when last cgroup event is removed. | |
988 | */ | |
989 | static inline void | |
990 | list_update_cgroup_event(struct perf_event *event, | |
991 | struct perf_event_context *ctx, bool add) | |
992 | { | |
993 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 994 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
995 | |
996 | if (!is_cgroup_event(event)) | |
997 | return; | |
998 | ||
db4a8356 DCC |
999 | /* |
1000 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1001 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1002 | */ |
07c59729 | 1003 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1004 | |
1005 | /* | |
1006 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1007 | * matching the event's cgroup, we must do this for every new event, | |
1008 | * because if the first would mismatch, the second would not try again | |
1009 | * and we would leave cpuctx->cgrp unset. | |
1010 | */ | |
1011 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
1012 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1013 | ||
be96b316 TH |
1014 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1015 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1016 | } |
33801b94 | 1017 | |
1018 | if (add && ctx->nr_cgroups++) | |
1019 | return; | |
1020 | else if (!add && --ctx->nr_cgroups) | |
1021 | return; | |
1022 | ||
1023 | /* no cgroup running */ | |
1024 | if (!add) | |
1025 | cpuctx->cgrp = NULL; | |
1026 | ||
1027 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
1028 | if (add) | |
07c59729 SL |
1029 | list_add(cpuctx_entry, |
1030 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
33801b94 | 1031 | else |
1032 | list_del(cpuctx_entry); | |
db4a8356 DCC |
1033 | } |
1034 | ||
e5d1367f SE |
1035 | #else /* !CONFIG_CGROUP_PERF */ |
1036 | ||
1037 | static inline bool | |
1038 | perf_cgroup_match(struct perf_event *event) | |
1039 | { | |
1040 | return true; | |
1041 | } | |
1042 | ||
1043 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1044 | {} | |
1045 | ||
1046 | static inline int is_cgroup_event(struct perf_event *event) | |
1047 | { | |
1048 | return 0; | |
1049 | } | |
1050 | ||
e5d1367f SE |
1051 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1052 | { | |
1053 | } | |
1054 | ||
1055 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1056 | { | |
1057 | } | |
1058 | ||
a8d757ef SE |
1059 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1060 | struct task_struct *next) | |
e5d1367f SE |
1061 | { |
1062 | } | |
1063 | ||
a8d757ef SE |
1064 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1065 | struct task_struct *task) | |
e5d1367f SE |
1066 | { |
1067 | } | |
1068 | ||
1069 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1070 | struct perf_event_attr *attr, | |
1071 | struct perf_event *group_leader) | |
1072 | { | |
1073 | return -EINVAL; | |
1074 | } | |
1075 | ||
1076 | static inline void | |
3f7cce3c SE |
1077 | perf_cgroup_set_timestamp(struct task_struct *task, |
1078 | struct perf_event_context *ctx) | |
e5d1367f SE |
1079 | { |
1080 | } | |
1081 | ||
d00dbd29 | 1082 | static inline void |
e5d1367f SE |
1083 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1084 | { | |
1085 | } | |
1086 | ||
1087 | static inline void | |
1088 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1089 | { | |
1090 | } | |
1091 | ||
1092 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1093 | { | |
1094 | return 0; | |
1095 | } | |
1096 | ||
db4a8356 DCC |
1097 | static inline void |
1098 | list_update_cgroup_event(struct perf_event *event, | |
1099 | struct perf_event_context *ctx, bool add) | |
1100 | { | |
1101 | } | |
1102 | ||
e5d1367f SE |
1103 | #endif |
1104 | ||
9e630205 SE |
1105 | /* |
1106 | * set default to be dependent on timer tick just | |
1107 | * like original code | |
1108 | */ | |
1109 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1110 | /* | |
8a1115ff | 1111 | * function must be called with interrupts disabled |
9e630205 | 1112 | */ |
272325c4 | 1113 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1114 | { |
1115 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1116 | bool rotations; |
9e630205 | 1117 | |
16444645 | 1118 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1119 | |
1120 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1121 | rotations = perf_rotate_context(cpuctx); |
1122 | ||
4cfafd30 PZ |
1123 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1124 | if (rotations) | |
9e630205 | 1125 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1126 | else |
1127 | cpuctx->hrtimer_active = 0; | |
1128 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1129 | |
4cfafd30 | 1130 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1131 | } |
1132 | ||
272325c4 | 1133 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1134 | { |
272325c4 | 1135 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1136 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1137 | u64 interval; |
9e630205 SE |
1138 | |
1139 | /* no multiplexing needed for SW PMU */ | |
1140 | if (pmu->task_ctx_nr == perf_sw_context) | |
1141 | return; | |
1142 | ||
62b85639 SE |
1143 | /* |
1144 | * check default is sane, if not set then force to | |
1145 | * default interval (1/tick) | |
1146 | */ | |
272325c4 PZ |
1147 | interval = pmu->hrtimer_interval_ms; |
1148 | if (interval < 1) | |
1149 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1150 | |
272325c4 | 1151 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1152 | |
4cfafd30 | 1153 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1154 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1155 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1156 | } |
1157 | ||
272325c4 | 1158 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1159 | { |
272325c4 | 1160 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1161 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1162 | unsigned long flags; |
9e630205 SE |
1163 | |
1164 | /* not for SW PMU */ | |
1165 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1166 | return 0; |
9e630205 | 1167 | |
4cfafd30 PZ |
1168 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1169 | if (!cpuctx->hrtimer_active) { | |
1170 | cpuctx->hrtimer_active = 1; | |
1171 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1172 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1173 | } |
1174 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1175 | |
272325c4 | 1176 | return 0; |
9e630205 SE |
1177 | } |
1178 | ||
33696fc0 | 1179 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1180 | { |
33696fc0 PZ |
1181 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1182 | if (!(*count)++) | |
1183 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1184 | } |
9e35ad38 | 1185 | |
33696fc0 | 1186 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1187 | { |
33696fc0 PZ |
1188 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1189 | if (!--(*count)) | |
1190 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1191 | } |
9e35ad38 | 1192 | |
2fde4f94 | 1193 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1194 | |
1195 | /* | |
2fde4f94 MR |
1196 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1197 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1198 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1199 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1200 | */ |
2fde4f94 | 1201 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1202 | { |
2fde4f94 | 1203 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1204 | |
16444645 | 1205 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1206 | |
2fde4f94 MR |
1207 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1208 | ||
1209 | list_add(&ctx->active_ctx_list, head); | |
1210 | } | |
1211 | ||
1212 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1213 | { | |
16444645 | 1214 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1215 | |
1216 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1217 | ||
1218 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1219 | } |
9e35ad38 | 1220 | |
cdd6c482 | 1221 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1222 | { |
8c94abbb | 1223 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1224 | } |
1225 | ||
4af57ef2 YZ |
1226 | static void free_ctx(struct rcu_head *head) |
1227 | { | |
1228 | struct perf_event_context *ctx; | |
1229 | ||
1230 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1231 | kfree(ctx->task_ctx_data); | |
1232 | kfree(ctx); | |
1233 | } | |
1234 | ||
cdd6c482 | 1235 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1236 | { |
8c94abbb | 1237 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1238 | if (ctx->parent_ctx) |
1239 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1240 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1241 | put_task_struct(ctx->task); |
4af57ef2 | 1242 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1243 | } |
a63eaf34 PM |
1244 | } |
1245 | ||
f63a8daa PZ |
1246 | /* |
1247 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1248 | * perf_pmu_migrate_context() we need some magic. | |
1249 | * | |
1250 | * Those places that change perf_event::ctx will hold both | |
1251 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1252 | * | |
8b10c5e2 PZ |
1253 | * Lock ordering is by mutex address. There are two other sites where |
1254 | * perf_event_context::mutex nests and those are: | |
1255 | * | |
1256 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1257 | * perf_event_exit_event() |
1258 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1259 | * |
1260 | * - perf_event_init_context() [ parent, 0 ] | |
1261 | * inherit_task_group() | |
1262 | * inherit_group() | |
1263 | * inherit_event() | |
1264 | * perf_event_alloc() | |
1265 | * perf_init_event() | |
1266 | * perf_try_init_event() [ child , 1 ] | |
1267 | * | |
1268 | * While it appears there is an obvious deadlock here -- the parent and child | |
1269 | * nesting levels are inverted between the two. This is in fact safe because | |
1270 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1271 | * spawning task cannot (yet) exit. | |
1272 | * | |
1273 | * But remember that that these are parent<->child context relations, and | |
1274 | * migration does not affect children, therefore these two orderings should not | |
1275 | * interact. | |
f63a8daa PZ |
1276 | * |
1277 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1278 | * because the sys_perf_event_open() case will install a new event and break | |
1279 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1280 | * concerned with cpuctx and that doesn't have children. | |
1281 | * | |
1282 | * The places that change perf_event::ctx will issue: | |
1283 | * | |
1284 | * perf_remove_from_context(); | |
1285 | * synchronize_rcu(); | |
1286 | * perf_install_in_context(); | |
1287 | * | |
1288 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1289 | * quiesce the event, after which we can install it in the new location. This | |
1290 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1291 | * while in transit. Therefore all such accessors should also acquire | |
1292 | * perf_event_context::mutex to serialize against this. | |
1293 | * | |
1294 | * However; because event->ctx can change while we're waiting to acquire | |
1295 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1296 | * function. | |
1297 | * | |
1298 | * Lock order: | |
69143038 | 1299 | * exec_update_mutex |
f63a8daa PZ |
1300 | * task_struct::perf_event_mutex |
1301 | * perf_event_context::mutex | |
f63a8daa | 1302 | * perf_event::child_mutex; |
07c4a776 | 1303 | * perf_event_context::lock |
f63a8daa PZ |
1304 | * perf_event::mmap_mutex |
1305 | * mmap_sem | |
18736eef | 1306 | * perf_addr_filters_head::lock |
82d94856 PZ |
1307 | * |
1308 | * cpu_hotplug_lock | |
1309 | * pmus_lock | |
1310 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1311 | */ |
a83fe28e PZ |
1312 | static struct perf_event_context * |
1313 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1314 | { |
1315 | struct perf_event_context *ctx; | |
1316 | ||
1317 | again: | |
1318 | rcu_read_lock(); | |
6aa7de05 | 1319 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1320 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1321 | rcu_read_unlock(); |
1322 | goto again; | |
1323 | } | |
1324 | rcu_read_unlock(); | |
1325 | ||
a83fe28e | 1326 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1327 | if (event->ctx != ctx) { |
1328 | mutex_unlock(&ctx->mutex); | |
1329 | put_ctx(ctx); | |
1330 | goto again; | |
1331 | } | |
1332 | ||
1333 | return ctx; | |
1334 | } | |
1335 | ||
a83fe28e PZ |
1336 | static inline struct perf_event_context * |
1337 | perf_event_ctx_lock(struct perf_event *event) | |
1338 | { | |
1339 | return perf_event_ctx_lock_nested(event, 0); | |
1340 | } | |
1341 | ||
f63a8daa PZ |
1342 | static void perf_event_ctx_unlock(struct perf_event *event, |
1343 | struct perf_event_context *ctx) | |
1344 | { | |
1345 | mutex_unlock(&ctx->mutex); | |
1346 | put_ctx(ctx); | |
1347 | } | |
1348 | ||
211de6eb PZ |
1349 | /* |
1350 | * This must be done under the ctx->lock, such as to serialize against | |
1351 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1352 | * calling scheduler related locks and ctx->lock nests inside those. | |
1353 | */ | |
1354 | static __must_check struct perf_event_context * | |
1355 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1356 | { |
211de6eb PZ |
1357 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1358 | ||
1359 | lockdep_assert_held(&ctx->lock); | |
1360 | ||
1361 | if (parent_ctx) | |
71a851b4 | 1362 | ctx->parent_ctx = NULL; |
5a3126d4 | 1363 | ctx->generation++; |
211de6eb PZ |
1364 | |
1365 | return parent_ctx; | |
71a851b4 PZ |
1366 | } |
1367 | ||
1d953111 ON |
1368 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1369 | enum pid_type type) | |
6844c09d | 1370 | { |
1d953111 | 1371 | u32 nr; |
6844c09d ACM |
1372 | /* |
1373 | * only top level events have the pid namespace they were created in | |
1374 | */ | |
1375 | if (event->parent) | |
1376 | event = event->parent; | |
1377 | ||
1d953111 ON |
1378 | nr = __task_pid_nr_ns(p, type, event->ns); |
1379 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1380 | if (!nr && !pid_alive(p)) | |
1381 | nr = -1; | |
1382 | return nr; | |
6844c09d ACM |
1383 | } |
1384 | ||
1d953111 | 1385 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1386 | { |
6883f81a | 1387 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1388 | } |
6844c09d | 1389 | |
1d953111 ON |
1390 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1391 | { | |
1392 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1393 | } |
1394 | ||
7f453c24 | 1395 | /* |
cdd6c482 | 1396 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1397 | * to userspace. |
1398 | */ | |
cdd6c482 | 1399 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1400 | { |
cdd6c482 | 1401 | u64 id = event->id; |
7f453c24 | 1402 | |
cdd6c482 IM |
1403 | if (event->parent) |
1404 | id = event->parent->id; | |
7f453c24 PZ |
1405 | |
1406 | return id; | |
1407 | } | |
1408 | ||
25346b93 | 1409 | /* |
cdd6c482 | 1410 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1411 | * |
25346b93 PM |
1412 | * This has to cope with with the fact that until it is locked, |
1413 | * the context could get moved to another task. | |
1414 | */ | |
cdd6c482 | 1415 | static struct perf_event_context * |
8dc85d54 | 1416 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1417 | { |
cdd6c482 | 1418 | struct perf_event_context *ctx; |
25346b93 | 1419 | |
9ed6060d | 1420 | retry: |
058ebd0e PZ |
1421 | /* |
1422 | * One of the few rules of preemptible RCU is that one cannot do | |
1423 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1424 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1425 | * rcu_read_unlock_special(). |
1426 | * | |
1427 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1428 | * side critical section has interrupts disabled. |
058ebd0e | 1429 | */ |
2fd59077 | 1430 | local_irq_save(*flags); |
058ebd0e | 1431 | rcu_read_lock(); |
8dc85d54 | 1432 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1433 | if (ctx) { |
1434 | /* | |
1435 | * If this context is a clone of another, it might | |
1436 | * get swapped for another underneath us by | |
cdd6c482 | 1437 | * perf_event_task_sched_out, though the |
25346b93 PM |
1438 | * rcu_read_lock() protects us from any context |
1439 | * getting freed. Lock the context and check if it | |
1440 | * got swapped before we could get the lock, and retry | |
1441 | * if so. If we locked the right context, then it | |
1442 | * can't get swapped on us any more. | |
1443 | */ | |
2fd59077 | 1444 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1445 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1446 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1447 | rcu_read_unlock(); |
2fd59077 | 1448 | local_irq_restore(*flags); |
25346b93 PM |
1449 | goto retry; |
1450 | } | |
b49a9e7e | 1451 | |
63b6da39 | 1452 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1453 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1454 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1455 | ctx = NULL; |
828b6f0e PZ |
1456 | } else { |
1457 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1458 | } |
25346b93 PM |
1459 | } |
1460 | rcu_read_unlock(); | |
2fd59077 PM |
1461 | if (!ctx) |
1462 | local_irq_restore(*flags); | |
25346b93 PM |
1463 | return ctx; |
1464 | } | |
1465 | ||
1466 | /* | |
1467 | * Get the context for a task and increment its pin_count so it | |
1468 | * can't get swapped to another task. This also increments its | |
1469 | * reference count so that the context can't get freed. | |
1470 | */ | |
8dc85d54 PZ |
1471 | static struct perf_event_context * |
1472 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1473 | { |
cdd6c482 | 1474 | struct perf_event_context *ctx; |
25346b93 PM |
1475 | unsigned long flags; |
1476 | ||
8dc85d54 | 1477 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1478 | if (ctx) { |
1479 | ++ctx->pin_count; | |
e625cce1 | 1480 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1481 | } |
1482 | return ctx; | |
1483 | } | |
1484 | ||
cdd6c482 | 1485 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1486 | { |
1487 | unsigned long flags; | |
1488 | ||
e625cce1 | 1489 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1490 | --ctx->pin_count; |
e625cce1 | 1491 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1492 | } |
1493 | ||
f67218c3 PZ |
1494 | /* |
1495 | * Update the record of the current time in a context. | |
1496 | */ | |
1497 | static void update_context_time(struct perf_event_context *ctx) | |
1498 | { | |
1499 | u64 now = perf_clock(); | |
1500 | ||
1501 | ctx->time += now - ctx->timestamp; | |
1502 | ctx->timestamp = now; | |
1503 | } | |
1504 | ||
4158755d SE |
1505 | static u64 perf_event_time(struct perf_event *event) |
1506 | { | |
1507 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1508 | |
1509 | if (is_cgroup_event(event)) | |
1510 | return perf_cgroup_event_time(event); | |
1511 | ||
4158755d SE |
1512 | return ctx ? ctx->time : 0; |
1513 | } | |
1514 | ||
487f05e1 AS |
1515 | static enum event_type_t get_event_type(struct perf_event *event) |
1516 | { | |
1517 | struct perf_event_context *ctx = event->ctx; | |
1518 | enum event_type_t event_type; | |
1519 | ||
1520 | lockdep_assert_held(&ctx->lock); | |
1521 | ||
3bda69c1 AS |
1522 | /* |
1523 | * It's 'group type', really, because if our group leader is | |
1524 | * pinned, so are we. | |
1525 | */ | |
1526 | if (event->group_leader != event) | |
1527 | event = event->group_leader; | |
1528 | ||
487f05e1 AS |
1529 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1530 | if (!ctx->task) | |
1531 | event_type |= EVENT_CPU; | |
1532 | ||
1533 | return event_type; | |
1534 | } | |
1535 | ||
8e1a2031 | 1536 | /* |
161c85fa | 1537 | * Helper function to initialize event group nodes. |
8e1a2031 | 1538 | */ |
161c85fa | 1539 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1540 | { |
1541 | RB_CLEAR_NODE(&event->group_node); | |
1542 | event->group_index = 0; | |
1543 | } | |
1544 | ||
1545 | /* | |
1546 | * Extract pinned or flexible groups from the context | |
161c85fa | 1547 | * based on event attrs bits. |
8e1a2031 AB |
1548 | */ |
1549 | static struct perf_event_groups * | |
1550 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1551 | { |
1552 | if (event->attr.pinned) | |
1553 | return &ctx->pinned_groups; | |
1554 | else | |
1555 | return &ctx->flexible_groups; | |
1556 | } | |
1557 | ||
8e1a2031 | 1558 | /* |
161c85fa | 1559 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1560 | */ |
161c85fa | 1561 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1562 | { |
1563 | groups->tree = RB_ROOT; | |
1564 | groups->index = 0; | |
1565 | } | |
1566 | ||
1567 | /* | |
1568 | * Compare function for event groups; | |
161c85fa PZ |
1569 | * |
1570 | * Implements complex key that first sorts by CPU and then by virtual index | |
1571 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1572 | */ |
161c85fa PZ |
1573 | static bool |
1574 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1575 | { |
161c85fa PZ |
1576 | if (left->cpu < right->cpu) |
1577 | return true; | |
1578 | if (left->cpu > right->cpu) | |
1579 | return false; | |
1580 | ||
95ed6c70 IR |
1581 | #ifdef CONFIG_CGROUP_PERF |
1582 | if (left->cgrp != right->cgrp) { | |
1583 | if (!left->cgrp || !left->cgrp->css.cgroup) { | |
1584 | /* | |
1585 | * Left has no cgroup but right does, no cgroups come | |
1586 | * first. | |
1587 | */ | |
1588 | return true; | |
1589 | } | |
a6763625 | 1590 | if (!right->cgrp || !right->cgrp->css.cgroup) { |
95ed6c70 IR |
1591 | /* |
1592 | * Right has no cgroup but left does, no cgroups come | |
1593 | * first. | |
1594 | */ | |
1595 | return false; | |
1596 | } | |
1597 | /* Two dissimilar cgroups, order by id. */ | |
1598 | if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) | |
1599 | return true; | |
1600 | ||
1601 | return false; | |
1602 | } | |
1603 | #endif | |
1604 | ||
161c85fa PZ |
1605 | if (left->group_index < right->group_index) |
1606 | return true; | |
1607 | if (left->group_index > right->group_index) | |
1608 | return false; | |
1609 | ||
1610 | return false; | |
8e1a2031 AB |
1611 | } |
1612 | ||
1613 | /* | |
161c85fa PZ |
1614 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1615 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1616 | * subtree. | |
8e1a2031 AB |
1617 | */ |
1618 | static void | |
1619 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1620 | struct perf_event *event) |
8e1a2031 AB |
1621 | { |
1622 | struct perf_event *node_event; | |
1623 | struct rb_node *parent; | |
1624 | struct rb_node **node; | |
1625 | ||
1626 | event->group_index = ++groups->index; | |
1627 | ||
1628 | node = &groups->tree.rb_node; | |
1629 | parent = *node; | |
1630 | ||
1631 | while (*node) { | |
1632 | parent = *node; | |
161c85fa | 1633 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1634 | |
1635 | if (perf_event_groups_less(event, node_event)) | |
1636 | node = &parent->rb_left; | |
1637 | else | |
1638 | node = &parent->rb_right; | |
1639 | } | |
1640 | ||
1641 | rb_link_node(&event->group_node, parent, node); | |
1642 | rb_insert_color(&event->group_node, &groups->tree); | |
1643 | } | |
1644 | ||
1645 | /* | |
161c85fa | 1646 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1647 | */ |
1648 | static void | |
1649 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1650 | { | |
1651 | struct perf_event_groups *groups; | |
1652 | ||
1653 | groups = get_event_groups(event, ctx); | |
1654 | perf_event_groups_insert(groups, event); | |
1655 | } | |
1656 | ||
1657 | /* | |
161c85fa | 1658 | * Delete a group from a tree. |
8e1a2031 AB |
1659 | */ |
1660 | static void | |
1661 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1662 | struct perf_event *event) |
8e1a2031 | 1663 | { |
161c85fa PZ |
1664 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1665 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1666 | |
161c85fa | 1667 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1668 | init_event_group(event); |
1669 | } | |
1670 | ||
1671 | /* | |
161c85fa | 1672 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1673 | */ |
1674 | static void | |
1675 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1676 | { | |
1677 | struct perf_event_groups *groups; | |
1678 | ||
1679 | groups = get_event_groups(event, ctx); | |
1680 | perf_event_groups_delete(groups, event); | |
1681 | } | |
1682 | ||
1683 | /* | |
95ed6c70 | 1684 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1685 | */ |
1686 | static struct perf_event * | |
95ed6c70 IR |
1687 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1688 | struct cgroup *cgrp) | |
8e1a2031 AB |
1689 | { |
1690 | struct perf_event *node_event = NULL, *match = NULL; | |
1691 | struct rb_node *node = groups->tree.rb_node; | |
95ed6c70 IR |
1692 | #ifdef CONFIG_CGROUP_PERF |
1693 | u64 node_cgrp_id, cgrp_id = 0; | |
1694 | ||
1695 | if (cgrp) | |
1696 | cgrp_id = cgrp->kn->id; | |
1697 | #endif | |
8e1a2031 AB |
1698 | |
1699 | while (node) { | |
161c85fa | 1700 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1701 | |
1702 | if (cpu < node_event->cpu) { | |
1703 | node = node->rb_left; | |
95ed6c70 IR |
1704 | continue; |
1705 | } | |
1706 | if (cpu > node_event->cpu) { | |
8e1a2031 | 1707 | node = node->rb_right; |
95ed6c70 IR |
1708 | continue; |
1709 | } | |
1710 | #ifdef CONFIG_CGROUP_PERF | |
1711 | node_cgrp_id = 0; | |
1712 | if (node_event->cgrp && node_event->cgrp->css.cgroup) | |
1713 | node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; | |
1714 | ||
1715 | if (cgrp_id < node_cgrp_id) { | |
8e1a2031 | 1716 | node = node->rb_left; |
95ed6c70 IR |
1717 | continue; |
1718 | } | |
1719 | if (cgrp_id > node_cgrp_id) { | |
1720 | node = node->rb_right; | |
1721 | continue; | |
8e1a2031 | 1722 | } |
95ed6c70 IR |
1723 | #endif |
1724 | match = node_event; | |
1725 | node = node->rb_left; | |
8e1a2031 AB |
1726 | } |
1727 | ||
1728 | return match; | |
1729 | } | |
1730 | ||
1cac7b1a PZ |
1731 | /* |
1732 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1733 | */ | |
1734 | static struct perf_event * | |
1735 | perf_event_groups_next(struct perf_event *event) | |
1736 | { | |
1737 | struct perf_event *next; | |
95ed6c70 IR |
1738 | #ifdef CONFIG_CGROUP_PERF |
1739 | u64 curr_cgrp_id = 0; | |
1740 | u64 next_cgrp_id = 0; | |
1741 | #endif | |
1cac7b1a PZ |
1742 | |
1743 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
95ed6c70 IR |
1744 | if (next == NULL || next->cpu != event->cpu) |
1745 | return NULL; | |
1746 | ||
1747 | #ifdef CONFIG_CGROUP_PERF | |
1748 | if (event->cgrp && event->cgrp->css.cgroup) | |
1749 | curr_cgrp_id = event->cgrp->css.cgroup->kn->id; | |
1cac7b1a | 1750 | |
95ed6c70 IR |
1751 | if (next->cgrp && next->cgrp->css.cgroup) |
1752 | next_cgrp_id = next->cgrp->css.cgroup->kn->id; | |
1753 | ||
1754 | if (curr_cgrp_id != next_cgrp_id) | |
1755 | return NULL; | |
1756 | #endif | |
1757 | return next; | |
1cac7b1a PZ |
1758 | } |
1759 | ||
8e1a2031 | 1760 | /* |
161c85fa | 1761 | * Iterate through the whole groups tree. |
8e1a2031 | 1762 | */ |
6e6804d2 PZ |
1763 | #define perf_event_groups_for_each(event, groups) \ |
1764 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1765 | typeof(*event), group_node); event; \ | |
1766 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1767 | typeof(*event), group_node)) | |
8e1a2031 | 1768 | |
fccc714b | 1769 | /* |
788faab7 | 1770 | * Add an event from the lists for its context. |
fccc714b PZ |
1771 | * Must be called with ctx->mutex and ctx->lock held. |
1772 | */ | |
04289bb9 | 1773 | static void |
cdd6c482 | 1774 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1775 | { |
c994d613 PZ |
1776 | lockdep_assert_held(&ctx->lock); |
1777 | ||
8a49542c PZ |
1778 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1779 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1780 | |
0d3d73aa PZ |
1781 | event->tstamp = perf_event_time(event); |
1782 | ||
04289bb9 | 1783 | /* |
8a49542c PZ |
1784 | * If we're a stand alone event or group leader, we go to the context |
1785 | * list, group events are kept attached to the group so that | |
1786 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1787 | */ |
8a49542c | 1788 | if (event->group_leader == event) { |
4ff6a8de | 1789 | event->group_caps = event->event_caps; |
8e1a2031 | 1790 | add_event_to_groups(event, ctx); |
5c148194 | 1791 | } |
592903cd | 1792 | |
db4a8356 | 1793 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1794 | |
cdd6c482 IM |
1795 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1796 | ctx->nr_events++; | |
1797 | if (event->attr.inherit_stat) | |
bfbd3381 | 1798 | ctx->nr_stat++; |
5a3126d4 PZ |
1799 | |
1800 | ctx->generation++; | |
04289bb9 IM |
1801 | } |
1802 | ||
0231bb53 JO |
1803 | /* |
1804 | * Initialize event state based on the perf_event_attr::disabled. | |
1805 | */ | |
1806 | static inline void perf_event__state_init(struct perf_event *event) | |
1807 | { | |
1808 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1809 | PERF_EVENT_STATE_INACTIVE; | |
1810 | } | |
1811 | ||
a723968c | 1812 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1813 | { |
1814 | int entry = sizeof(u64); /* value */ | |
1815 | int size = 0; | |
1816 | int nr = 1; | |
1817 | ||
1818 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1819 | size += sizeof(u64); | |
1820 | ||
1821 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1822 | size += sizeof(u64); | |
1823 | ||
1824 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1825 | entry += sizeof(u64); | |
1826 | ||
1827 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1828 | nr += nr_siblings; |
c320c7b7 ACM |
1829 | size += sizeof(u64); |
1830 | } | |
1831 | ||
1832 | size += entry * nr; | |
1833 | event->read_size = size; | |
1834 | } | |
1835 | ||
a723968c | 1836 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1837 | { |
1838 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1839 | u16 size = 0; |
1840 | ||
c320c7b7 ACM |
1841 | if (sample_type & PERF_SAMPLE_IP) |
1842 | size += sizeof(data->ip); | |
1843 | ||
6844c09d ACM |
1844 | if (sample_type & PERF_SAMPLE_ADDR) |
1845 | size += sizeof(data->addr); | |
1846 | ||
1847 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1848 | size += sizeof(data->period); | |
1849 | ||
c3feedf2 AK |
1850 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1851 | size += sizeof(data->weight); | |
1852 | ||
6844c09d ACM |
1853 | if (sample_type & PERF_SAMPLE_READ) |
1854 | size += event->read_size; | |
1855 | ||
d6be9ad6 SE |
1856 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1857 | size += sizeof(data->data_src.val); | |
1858 | ||
fdfbbd07 AK |
1859 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1860 | size += sizeof(data->txn); | |
1861 | ||
fc7ce9c7 KL |
1862 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1863 | size += sizeof(data->phys_addr); | |
1864 | ||
6546b19f NK |
1865 | if (sample_type & PERF_SAMPLE_CGROUP) |
1866 | size += sizeof(data->cgroup); | |
1867 | ||
6844c09d ACM |
1868 | event->header_size = size; |
1869 | } | |
1870 | ||
a723968c PZ |
1871 | /* |
1872 | * Called at perf_event creation and when events are attached/detached from a | |
1873 | * group. | |
1874 | */ | |
1875 | static void perf_event__header_size(struct perf_event *event) | |
1876 | { | |
1877 | __perf_event_read_size(event, | |
1878 | event->group_leader->nr_siblings); | |
1879 | __perf_event_header_size(event, event->attr.sample_type); | |
1880 | } | |
1881 | ||
6844c09d ACM |
1882 | static void perf_event__id_header_size(struct perf_event *event) |
1883 | { | |
1884 | struct perf_sample_data *data; | |
1885 | u64 sample_type = event->attr.sample_type; | |
1886 | u16 size = 0; | |
1887 | ||
c320c7b7 ACM |
1888 | if (sample_type & PERF_SAMPLE_TID) |
1889 | size += sizeof(data->tid_entry); | |
1890 | ||
1891 | if (sample_type & PERF_SAMPLE_TIME) | |
1892 | size += sizeof(data->time); | |
1893 | ||
ff3d527c AH |
1894 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1895 | size += sizeof(data->id); | |
1896 | ||
c320c7b7 ACM |
1897 | if (sample_type & PERF_SAMPLE_ID) |
1898 | size += sizeof(data->id); | |
1899 | ||
1900 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1901 | size += sizeof(data->stream_id); | |
1902 | ||
1903 | if (sample_type & PERF_SAMPLE_CPU) | |
1904 | size += sizeof(data->cpu_entry); | |
1905 | ||
6844c09d | 1906 | event->id_header_size = size; |
c320c7b7 ACM |
1907 | } |
1908 | ||
a723968c PZ |
1909 | static bool perf_event_validate_size(struct perf_event *event) |
1910 | { | |
1911 | /* | |
1912 | * The values computed here will be over-written when we actually | |
1913 | * attach the event. | |
1914 | */ | |
1915 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1916 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1917 | perf_event__id_header_size(event); | |
1918 | ||
1919 | /* | |
1920 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1921 | * Conservative limit to allow for callchains and other variable fields. | |
1922 | */ | |
1923 | if (event->read_size + event->header_size + | |
1924 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1925 | return false; | |
1926 | ||
1927 | return true; | |
1928 | } | |
1929 | ||
8a49542c PZ |
1930 | static void perf_group_attach(struct perf_event *event) |
1931 | { | |
c320c7b7 | 1932 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1933 | |
a76a82a3 PZ |
1934 | lockdep_assert_held(&event->ctx->lock); |
1935 | ||
74c3337c PZ |
1936 | /* |
1937 | * We can have double attach due to group movement in perf_event_open. | |
1938 | */ | |
1939 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1940 | return; | |
1941 | ||
8a49542c PZ |
1942 | event->attach_state |= PERF_ATTACH_GROUP; |
1943 | ||
1944 | if (group_leader == event) | |
1945 | return; | |
1946 | ||
652884fe PZ |
1947 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1948 | ||
4ff6a8de | 1949 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1950 | |
8343aae6 | 1951 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1952 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1953 | |
1954 | perf_event__header_size(group_leader); | |
1955 | ||
edb39592 | 1956 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1957 | perf_event__header_size(pos); |
8a49542c PZ |
1958 | } |
1959 | ||
a63eaf34 | 1960 | /* |
788faab7 | 1961 | * Remove an event from the lists for its context. |
fccc714b | 1962 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1963 | */ |
04289bb9 | 1964 | static void |
cdd6c482 | 1965 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1966 | { |
652884fe PZ |
1967 | WARN_ON_ONCE(event->ctx != ctx); |
1968 | lockdep_assert_held(&ctx->lock); | |
1969 | ||
8a49542c PZ |
1970 | /* |
1971 | * We can have double detach due to exit/hot-unplug + close. | |
1972 | */ | |
1973 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1974 | return; |
8a49542c PZ |
1975 | |
1976 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1977 | ||
db4a8356 | 1978 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1979 | |
cdd6c482 IM |
1980 | ctx->nr_events--; |
1981 | if (event->attr.inherit_stat) | |
bfbd3381 | 1982 | ctx->nr_stat--; |
8bc20959 | 1983 | |
cdd6c482 | 1984 | list_del_rcu(&event->event_entry); |
04289bb9 | 1985 | |
8a49542c | 1986 | if (event->group_leader == event) |
8e1a2031 | 1987 | del_event_from_groups(event, ctx); |
5c148194 | 1988 | |
b2e74a26 SE |
1989 | /* |
1990 | * If event was in error state, then keep it | |
1991 | * that way, otherwise bogus counts will be | |
1992 | * returned on read(). The only way to get out | |
1993 | * of error state is by explicit re-enabling | |
1994 | * of the event | |
1995 | */ | |
1996 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1997 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1998 | |
1999 | ctx->generation++; | |
050735b0 PZ |
2000 | } |
2001 | ||
ab43762e AS |
2002 | static int |
2003 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2004 | { | |
2005 | if (!has_aux(aux_event)) | |
2006 | return 0; | |
2007 | ||
2008 | if (!event->pmu->aux_output_match) | |
2009 | return 0; | |
2010 | ||
2011 | return event->pmu->aux_output_match(aux_event); | |
2012 | } | |
2013 | ||
2014 | static void put_event(struct perf_event *event); | |
2015 | static void event_sched_out(struct perf_event *event, | |
2016 | struct perf_cpu_context *cpuctx, | |
2017 | struct perf_event_context *ctx); | |
2018 | ||
2019 | static void perf_put_aux_event(struct perf_event *event) | |
2020 | { | |
2021 | struct perf_event_context *ctx = event->ctx; | |
2022 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2023 | struct perf_event *iter; | |
2024 | ||
2025 | /* | |
2026 | * If event uses aux_event tear down the link | |
2027 | */ | |
2028 | if (event->aux_event) { | |
2029 | iter = event->aux_event; | |
2030 | event->aux_event = NULL; | |
2031 | put_event(iter); | |
2032 | return; | |
2033 | } | |
2034 | ||
2035 | /* | |
2036 | * If the event is an aux_event, tear down all links to | |
2037 | * it from other events. | |
2038 | */ | |
2039 | for_each_sibling_event(iter, event->group_leader) { | |
2040 | if (iter->aux_event != event) | |
2041 | continue; | |
2042 | ||
2043 | iter->aux_event = NULL; | |
2044 | put_event(event); | |
2045 | ||
2046 | /* | |
2047 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2048 | * state so that we don't try to schedule it again. Note | |
2049 | * that perf_event_enable() will clear the ERROR status. | |
2050 | */ | |
2051 | event_sched_out(iter, cpuctx, ctx); | |
2052 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2053 | } | |
2054 | } | |
2055 | ||
a4faf00d AS |
2056 | static bool perf_need_aux_event(struct perf_event *event) |
2057 | { | |
2058 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2059 | } | |
2060 | ||
ab43762e AS |
2061 | static int perf_get_aux_event(struct perf_event *event, |
2062 | struct perf_event *group_leader) | |
2063 | { | |
2064 | /* | |
2065 | * Our group leader must be an aux event if we want to be | |
2066 | * an aux_output. This way, the aux event will precede its | |
2067 | * aux_output events in the group, and therefore will always | |
2068 | * schedule first. | |
2069 | */ | |
2070 | if (!group_leader) | |
2071 | return 0; | |
2072 | ||
a4faf00d AS |
2073 | /* |
2074 | * aux_output and aux_sample_size are mutually exclusive. | |
2075 | */ | |
2076 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2077 | return 0; | |
2078 | ||
2079 | if (event->attr.aux_output && | |
2080 | !perf_aux_output_match(event, group_leader)) | |
2081 | return 0; | |
2082 | ||
2083 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2084 | return 0; |
2085 | ||
2086 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2087 | return 0; | |
2088 | ||
2089 | /* | |
2090 | * Link aux_outputs to their aux event; this is undone in | |
2091 | * perf_group_detach() by perf_put_aux_event(). When the | |
2092 | * group in torn down, the aux_output events loose their | |
2093 | * link to the aux_event and can't schedule any more. | |
2094 | */ | |
2095 | event->aux_event = group_leader; | |
2096 | ||
2097 | return 1; | |
2098 | } | |
2099 | ||
ab6f824c PZ |
2100 | static inline struct list_head *get_event_list(struct perf_event *event) |
2101 | { | |
2102 | struct perf_event_context *ctx = event->ctx; | |
2103 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2104 | } | |
2105 | ||
8a49542c | 2106 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
2107 | { |
2108 | struct perf_event *sibling, *tmp; | |
6668128a | 2109 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2110 | |
6668128a | 2111 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2112 | |
8a49542c PZ |
2113 | /* |
2114 | * We can have double detach due to exit/hot-unplug + close. | |
2115 | */ | |
2116 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2117 | return; | |
2118 | ||
2119 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2120 | ||
ab43762e AS |
2121 | perf_put_aux_event(event); |
2122 | ||
8a49542c PZ |
2123 | /* |
2124 | * If this is a sibling, remove it from its group. | |
2125 | */ | |
2126 | if (event->group_leader != event) { | |
8343aae6 | 2127 | list_del_init(&event->sibling_list); |
8a49542c | 2128 | event->group_leader->nr_siblings--; |
c320c7b7 | 2129 | goto out; |
8a49542c PZ |
2130 | } |
2131 | ||
04289bb9 | 2132 | /* |
cdd6c482 IM |
2133 | * If this was a group event with sibling events then |
2134 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2135 | * to whatever list we are on. |
04289bb9 | 2136 | */ |
8343aae6 | 2137 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2138 | |
04289bb9 | 2139 | sibling->group_leader = sibling; |
24868367 | 2140 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2141 | |
2142 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2143 | sibling->group_caps = event->group_caps; |
652884fe | 2144 | |
8e1a2031 | 2145 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2146 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2147 | |
ab6f824c PZ |
2148 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2149 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2150 | } |
2151 | ||
652884fe | 2152 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2153 | } |
c320c7b7 ACM |
2154 | |
2155 | out: | |
2156 | perf_event__header_size(event->group_leader); | |
2157 | ||
edb39592 | 2158 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 2159 | perf_event__header_size(tmp); |
04289bb9 IM |
2160 | } |
2161 | ||
fadfe7be JO |
2162 | static bool is_orphaned_event(struct perf_event *event) |
2163 | { | |
a69b0ca4 | 2164 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2165 | } |
2166 | ||
2c81a647 | 2167 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2168 | { |
2169 | struct pmu *pmu = event->pmu; | |
2170 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2171 | } | |
2172 | ||
2c81a647 MR |
2173 | /* |
2174 | * Check whether we should attempt to schedule an event group based on | |
2175 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2176 | * potentially with a SW leader, so we must check all the filters, to | |
2177 | * determine whether a group is schedulable: | |
2178 | */ | |
2179 | static inline int pmu_filter_match(struct perf_event *event) | |
2180 | { | |
edb39592 | 2181 | struct perf_event *sibling; |
2c81a647 MR |
2182 | |
2183 | if (!__pmu_filter_match(event)) | |
2184 | return 0; | |
2185 | ||
edb39592 PZ |
2186 | for_each_sibling_event(sibling, event) { |
2187 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2188 | return 0; |
2189 | } | |
2190 | ||
2191 | return 1; | |
2192 | } | |
2193 | ||
fa66f07a SE |
2194 | static inline int |
2195 | event_filter_match(struct perf_event *event) | |
2196 | { | |
0b8f1e2e PZ |
2197 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2198 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2199 | } |
2200 | ||
9ffcfa6f SE |
2201 | static void |
2202 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2203 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2204 | struct perf_event_context *ctx) |
3b6f9e5c | 2205 | { |
0d3d73aa | 2206 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2207 | |
2208 | WARN_ON_ONCE(event->ctx != ctx); | |
2209 | lockdep_assert_held(&ctx->lock); | |
2210 | ||
cdd6c482 | 2211 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2212 | return; |
3b6f9e5c | 2213 | |
6668128a PZ |
2214 | /* |
2215 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2216 | * we can schedule events _OUT_ individually through things like | |
2217 | * __perf_remove_from_context(). | |
2218 | */ | |
2219 | list_del_init(&event->active_list); | |
2220 | ||
44377277 AS |
2221 | perf_pmu_disable(event->pmu); |
2222 | ||
28a967c3 PZ |
2223 | event->pmu->del(event, 0); |
2224 | event->oncpu = -1; | |
0d3d73aa | 2225 | |
1d54ad94 PZ |
2226 | if (READ_ONCE(event->pending_disable) >= 0) { |
2227 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 2228 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2229 | } |
0d3d73aa | 2230 | perf_event_set_state(event, state); |
3b6f9e5c | 2231 | |
cdd6c482 | 2232 | if (!is_software_event(event)) |
3b6f9e5c | 2233 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2234 | if (!--ctx->nr_active) |
2235 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2236 | if (event->attr.freq && event->attr.sample_freq) |
2237 | ctx->nr_freq--; | |
cdd6c482 | 2238 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2239 | cpuctx->exclusive = 0; |
44377277 AS |
2240 | |
2241 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2242 | } |
2243 | ||
d859e29f | 2244 | static void |
cdd6c482 | 2245 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2246 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2247 | struct perf_event_context *ctx) |
d859e29f | 2248 | { |
cdd6c482 | 2249 | struct perf_event *event; |
0d3d73aa PZ |
2250 | |
2251 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2252 | return; | |
d859e29f | 2253 | |
3f005e7d MR |
2254 | perf_pmu_disable(ctx->pmu); |
2255 | ||
cdd6c482 | 2256 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2257 | |
2258 | /* | |
2259 | * Schedule out siblings (if any): | |
2260 | */ | |
edb39592 | 2261 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2262 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2263 | |
3f005e7d MR |
2264 | perf_pmu_enable(ctx->pmu); |
2265 | ||
0d3d73aa | 2266 | if (group_event->attr.exclusive) |
d859e29f PM |
2267 | cpuctx->exclusive = 0; |
2268 | } | |
2269 | ||
45a0e07a | 2270 | #define DETACH_GROUP 0x01UL |
0017960f | 2271 | |
0793a61d | 2272 | /* |
cdd6c482 | 2273 | * Cross CPU call to remove a performance event |
0793a61d | 2274 | * |
cdd6c482 | 2275 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2276 | * remove it from the context list. |
2277 | */ | |
fae3fde6 PZ |
2278 | static void |
2279 | __perf_remove_from_context(struct perf_event *event, | |
2280 | struct perf_cpu_context *cpuctx, | |
2281 | struct perf_event_context *ctx, | |
2282 | void *info) | |
0793a61d | 2283 | { |
45a0e07a | 2284 | unsigned long flags = (unsigned long)info; |
0793a61d | 2285 | |
3c5c8711 PZ |
2286 | if (ctx->is_active & EVENT_TIME) { |
2287 | update_context_time(ctx); | |
2288 | update_cgrp_time_from_cpuctx(cpuctx); | |
2289 | } | |
2290 | ||
cdd6c482 | 2291 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2292 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2293 | perf_group_detach(event); |
cdd6c482 | 2294 | list_del_event(event, ctx); |
39a43640 PZ |
2295 | |
2296 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2297 | ctx->is_active = 0; |
90c91dfb | 2298 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2299 | if (ctx->task) { |
2300 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2301 | cpuctx->task_ctx = NULL; | |
2302 | } | |
64ce3126 | 2303 | } |
0793a61d TG |
2304 | } |
2305 | ||
0793a61d | 2306 | /* |
cdd6c482 | 2307 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2308 | * |
cdd6c482 IM |
2309 | * If event->ctx is a cloned context, callers must make sure that |
2310 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2311 | * remains valid. This is OK when called from perf_release since |
2312 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2313 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2314 | * context has been detached from its task. |
0793a61d | 2315 | */ |
45a0e07a | 2316 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2317 | { |
a76a82a3 PZ |
2318 | struct perf_event_context *ctx = event->ctx; |
2319 | ||
2320 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2321 | |
45a0e07a | 2322 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2323 | |
2324 | /* | |
2325 | * The above event_function_call() can NO-OP when it hits | |
2326 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2327 | * from the context (by perf_event_exit_event()) but the grouping | |
2328 | * might still be in-tact. | |
2329 | */ | |
2330 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2331 | if ((flags & DETACH_GROUP) && | |
2332 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2333 | /* | |
2334 | * Since in that case we cannot possibly be scheduled, simply | |
2335 | * detach now. | |
2336 | */ | |
2337 | raw_spin_lock_irq(&ctx->lock); | |
2338 | perf_group_detach(event); | |
2339 | raw_spin_unlock_irq(&ctx->lock); | |
2340 | } | |
0793a61d TG |
2341 | } |
2342 | ||
d859e29f | 2343 | /* |
cdd6c482 | 2344 | * Cross CPU call to disable a performance event |
d859e29f | 2345 | */ |
fae3fde6 PZ |
2346 | static void __perf_event_disable(struct perf_event *event, |
2347 | struct perf_cpu_context *cpuctx, | |
2348 | struct perf_event_context *ctx, | |
2349 | void *info) | |
7b648018 | 2350 | { |
fae3fde6 PZ |
2351 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2352 | return; | |
7b648018 | 2353 | |
3c5c8711 PZ |
2354 | if (ctx->is_active & EVENT_TIME) { |
2355 | update_context_time(ctx); | |
2356 | update_cgrp_time_from_event(event); | |
2357 | } | |
2358 | ||
fae3fde6 PZ |
2359 | if (event == event->group_leader) |
2360 | group_sched_out(event, cpuctx, ctx); | |
2361 | else | |
2362 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2363 | |
2364 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2365 | } |
2366 | ||
d859e29f | 2367 | /* |
788faab7 | 2368 | * Disable an event. |
c93f7669 | 2369 | * |
cdd6c482 IM |
2370 | * If event->ctx is a cloned context, callers must make sure that |
2371 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2372 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2373 | * perf_event_for_each_child or perf_event_for_each because they |
2374 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2375 | * goes to exit will block in perf_event_exit_event(). |
2376 | * | |
cdd6c482 | 2377 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2378 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2379 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2380 | */ |
f63a8daa | 2381 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2382 | { |
cdd6c482 | 2383 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2384 | |
e625cce1 | 2385 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2386 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2387 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2388 | return; |
53cfbf59 | 2389 | } |
e625cce1 | 2390 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2391 | |
fae3fde6 PZ |
2392 | event_function_call(event, __perf_event_disable, NULL); |
2393 | } | |
2394 | ||
2395 | void perf_event_disable_local(struct perf_event *event) | |
2396 | { | |
2397 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2398 | } |
f63a8daa PZ |
2399 | |
2400 | /* | |
2401 | * Strictly speaking kernel users cannot create groups and therefore this | |
2402 | * interface does not need the perf_event_ctx_lock() magic. | |
2403 | */ | |
2404 | void perf_event_disable(struct perf_event *event) | |
2405 | { | |
2406 | struct perf_event_context *ctx; | |
2407 | ||
2408 | ctx = perf_event_ctx_lock(event); | |
2409 | _perf_event_disable(event); | |
2410 | perf_event_ctx_unlock(event, ctx); | |
2411 | } | |
dcfce4a0 | 2412 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2413 | |
5aab90ce JO |
2414 | void perf_event_disable_inatomic(struct perf_event *event) |
2415 | { | |
1d54ad94 PZ |
2416 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2417 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2418 | irq_work_queue(&event->pending); |
2419 | } | |
2420 | ||
e5d1367f | 2421 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2422 | struct perf_event_context *ctx) |
e5d1367f SE |
2423 | { |
2424 | /* | |
2425 | * use the correct time source for the time snapshot | |
2426 | * | |
2427 | * We could get by without this by leveraging the | |
2428 | * fact that to get to this function, the caller | |
2429 | * has most likely already called update_context_time() | |
2430 | * and update_cgrp_time_xx() and thus both timestamp | |
2431 | * are identical (or very close). Given that tstamp is, | |
2432 | * already adjusted for cgroup, we could say that: | |
2433 | * tstamp - ctx->timestamp | |
2434 | * is equivalent to | |
2435 | * tstamp - cgrp->timestamp. | |
2436 | * | |
2437 | * Then, in perf_output_read(), the calculation would | |
2438 | * work with no changes because: | |
2439 | * - event is guaranteed scheduled in | |
2440 | * - no scheduled out in between | |
2441 | * - thus the timestamp would be the same | |
2442 | * | |
2443 | * But this is a bit hairy. | |
2444 | * | |
2445 | * So instead, we have an explicit cgroup call to remain | |
2446 | * within the time time source all along. We believe it | |
2447 | * is cleaner and simpler to understand. | |
2448 | */ | |
2449 | if (is_cgroup_event(event)) | |
0d3d73aa | 2450 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2451 | else |
0d3d73aa | 2452 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2453 | } |
2454 | ||
4fe757dd PZ |
2455 | #define MAX_INTERRUPTS (~0ULL) |
2456 | ||
2457 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2458 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2459 | |
235c7fc7 | 2460 | static int |
9ffcfa6f | 2461 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2462 | struct perf_cpu_context *cpuctx, |
6e37738a | 2463 | struct perf_event_context *ctx) |
235c7fc7 | 2464 | { |
44377277 | 2465 | int ret = 0; |
4158755d | 2466 | |
ab6f824c PZ |
2467 | WARN_ON_ONCE(event->ctx != ctx); |
2468 | ||
63342411 PZ |
2469 | lockdep_assert_held(&ctx->lock); |
2470 | ||
cdd6c482 | 2471 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2472 | return 0; |
2473 | ||
95ff4ca2 AS |
2474 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2475 | /* | |
0c1cbc18 PZ |
2476 | * Order event::oncpu write to happen before the ACTIVE state is |
2477 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2478 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2479 | */ |
2480 | smp_wmb(); | |
0d3d73aa | 2481 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2482 | |
2483 | /* | |
2484 | * Unthrottle events, since we scheduled we might have missed several | |
2485 | * ticks already, also for a heavily scheduling task there is little | |
2486 | * guarantee it'll get a tick in a timely manner. | |
2487 | */ | |
2488 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2489 | perf_log_throttle(event, 1); | |
2490 | event->hw.interrupts = 0; | |
2491 | } | |
2492 | ||
44377277 AS |
2493 | perf_pmu_disable(event->pmu); |
2494 | ||
0d3d73aa | 2495 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2496 | |
ec0d7729 AS |
2497 | perf_log_itrace_start(event); |
2498 | ||
a4eaf7f1 | 2499 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2500 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2501 | event->oncpu = -1; |
44377277 AS |
2502 | ret = -EAGAIN; |
2503 | goto out; | |
235c7fc7 IM |
2504 | } |
2505 | ||
cdd6c482 | 2506 | if (!is_software_event(event)) |
3b6f9e5c | 2507 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2508 | if (!ctx->nr_active++) |
2509 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2510 | if (event->attr.freq && event->attr.sample_freq) |
2511 | ctx->nr_freq++; | |
235c7fc7 | 2512 | |
cdd6c482 | 2513 | if (event->attr.exclusive) |
3b6f9e5c PM |
2514 | cpuctx->exclusive = 1; |
2515 | ||
44377277 AS |
2516 | out: |
2517 | perf_pmu_enable(event->pmu); | |
2518 | ||
2519 | return ret; | |
235c7fc7 IM |
2520 | } |
2521 | ||
6751b71e | 2522 | static int |
cdd6c482 | 2523 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2524 | struct perf_cpu_context *cpuctx, |
6e37738a | 2525 | struct perf_event_context *ctx) |
6751b71e | 2526 | { |
6bde9b6c | 2527 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2528 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2529 | |
cdd6c482 | 2530 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2531 | return 0; |
2532 | ||
fbbe0701 | 2533 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2534 | |
9ffcfa6f | 2535 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2536 | pmu->cancel_txn(pmu); |
272325c4 | 2537 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2538 | return -EAGAIN; |
90151c35 | 2539 | } |
6751b71e PM |
2540 | |
2541 | /* | |
2542 | * Schedule in siblings as one group (if any): | |
2543 | */ | |
edb39592 | 2544 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2545 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2546 | partial_group = event; |
6751b71e PM |
2547 | goto group_error; |
2548 | } | |
2549 | } | |
2550 | ||
9ffcfa6f | 2551 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2552 | return 0; |
9ffcfa6f | 2553 | |
6751b71e PM |
2554 | group_error: |
2555 | /* | |
2556 | * Groups can be scheduled in as one unit only, so undo any | |
2557 | * partial group before returning: | |
0d3d73aa | 2558 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2559 | */ |
edb39592 | 2560 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2561 | if (event == partial_group) |
0d3d73aa | 2562 | break; |
d7842da4 | 2563 | |
0d3d73aa | 2564 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2565 | } |
9ffcfa6f | 2566 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2567 | |
ad5133b7 | 2568 | pmu->cancel_txn(pmu); |
90151c35 | 2569 | |
272325c4 | 2570 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2571 | |
6751b71e PM |
2572 | return -EAGAIN; |
2573 | } | |
2574 | ||
3b6f9e5c | 2575 | /* |
cdd6c482 | 2576 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2577 | */ |
cdd6c482 | 2578 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2579 | struct perf_cpu_context *cpuctx, |
2580 | int can_add_hw) | |
2581 | { | |
2582 | /* | |
cdd6c482 | 2583 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2584 | */ |
4ff6a8de | 2585 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2586 | return 1; |
2587 | /* | |
2588 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2589 | * events can go on. |
3b6f9e5c PM |
2590 | */ |
2591 | if (cpuctx->exclusive) | |
2592 | return 0; | |
2593 | /* | |
2594 | * If this group is exclusive and there are already | |
cdd6c482 | 2595 | * events on the CPU, it can't go on. |
3b6f9e5c | 2596 | */ |
cdd6c482 | 2597 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2598 | return 0; |
2599 | /* | |
2600 | * Otherwise, try to add it if all previous groups were able | |
2601 | * to go on. | |
2602 | */ | |
2603 | return can_add_hw; | |
2604 | } | |
2605 | ||
cdd6c482 IM |
2606 | static void add_event_to_ctx(struct perf_event *event, |
2607 | struct perf_event_context *ctx) | |
53cfbf59 | 2608 | { |
cdd6c482 | 2609 | list_add_event(event, ctx); |
8a49542c | 2610 | perf_group_attach(event); |
53cfbf59 PM |
2611 | } |
2612 | ||
bd2afa49 PZ |
2613 | static void ctx_sched_out(struct perf_event_context *ctx, |
2614 | struct perf_cpu_context *cpuctx, | |
2615 | enum event_type_t event_type); | |
2c29ef0f PZ |
2616 | static void |
2617 | ctx_sched_in(struct perf_event_context *ctx, | |
2618 | struct perf_cpu_context *cpuctx, | |
2619 | enum event_type_t event_type, | |
2620 | struct task_struct *task); | |
fe4b04fa | 2621 | |
bd2afa49 | 2622 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2623 | struct perf_event_context *ctx, |
2624 | enum event_type_t event_type) | |
bd2afa49 PZ |
2625 | { |
2626 | if (!cpuctx->task_ctx) | |
2627 | return; | |
2628 | ||
2629 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2630 | return; | |
2631 | ||
487f05e1 | 2632 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2633 | } |
2634 | ||
dce5855b PZ |
2635 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2636 | struct perf_event_context *ctx, | |
2637 | struct task_struct *task) | |
2638 | { | |
2639 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2640 | if (ctx) | |
2641 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2642 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2643 | if (ctx) | |
2644 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2645 | } | |
2646 | ||
487f05e1 AS |
2647 | /* |
2648 | * We want to maintain the following priority of scheduling: | |
2649 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2650 | * - task pinned (EVENT_PINNED) | |
2651 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2652 | * - task flexible (EVENT_FLEXIBLE). | |
2653 | * | |
2654 | * In order to avoid unscheduling and scheduling back in everything every | |
2655 | * time an event is added, only do it for the groups of equal priority and | |
2656 | * below. | |
2657 | * | |
2658 | * This can be called after a batch operation on task events, in which case | |
2659 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2660 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2661 | */ | |
3e349507 | 2662 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2663 | struct perf_event_context *task_ctx, |
2664 | enum event_type_t event_type) | |
0017960f | 2665 | { |
bd903afe | 2666 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2667 | bool cpu_event = !!(event_type & EVENT_CPU); |
2668 | ||
2669 | /* | |
2670 | * If pinned groups are involved, flexible groups also need to be | |
2671 | * scheduled out. | |
2672 | */ | |
2673 | if (event_type & EVENT_PINNED) | |
2674 | event_type |= EVENT_FLEXIBLE; | |
2675 | ||
bd903afe SL |
2676 | ctx_event_type = event_type & EVENT_ALL; |
2677 | ||
3e349507 PZ |
2678 | perf_pmu_disable(cpuctx->ctx.pmu); |
2679 | if (task_ctx) | |
487f05e1 AS |
2680 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2681 | ||
2682 | /* | |
2683 | * Decide which cpu ctx groups to schedule out based on the types | |
2684 | * of events that caused rescheduling: | |
2685 | * - EVENT_CPU: schedule out corresponding groups; | |
2686 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2687 | * - otherwise, do nothing more. | |
2688 | */ | |
2689 | if (cpu_event) | |
2690 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2691 | else if (ctx_event_type & EVENT_PINNED) | |
2692 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2693 | ||
3e349507 PZ |
2694 | perf_event_sched_in(cpuctx, task_ctx, current); |
2695 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2696 | } |
2697 | ||
c68d224e SE |
2698 | void perf_pmu_resched(struct pmu *pmu) |
2699 | { | |
2700 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2701 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2702 | ||
2703 | perf_ctx_lock(cpuctx, task_ctx); | |
2704 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2705 | perf_ctx_unlock(cpuctx, task_ctx); | |
2706 | } | |
2707 | ||
0793a61d | 2708 | /* |
cdd6c482 | 2709 | * Cross CPU call to install and enable a performance event |
682076ae | 2710 | * |
a096309b PZ |
2711 | * Very similar to remote_function() + event_function() but cannot assume that |
2712 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2713 | */ |
fe4b04fa | 2714 | static int __perf_install_in_context(void *info) |
0793a61d | 2715 | { |
a096309b PZ |
2716 | struct perf_event *event = info; |
2717 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2718 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2719 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2720 | bool reprogram = true; |
a096309b | 2721 | int ret = 0; |
0793a61d | 2722 | |
63b6da39 | 2723 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2724 | if (ctx->task) { |
b58f6b0d PZ |
2725 | raw_spin_lock(&ctx->lock); |
2726 | task_ctx = ctx; | |
a096309b | 2727 | |
63cae12b | 2728 | reprogram = (ctx->task == current); |
b58f6b0d | 2729 | |
39a43640 | 2730 | /* |
63cae12b PZ |
2731 | * If the task is running, it must be running on this CPU, |
2732 | * otherwise we cannot reprogram things. | |
2733 | * | |
2734 | * If its not running, we don't care, ctx->lock will | |
2735 | * serialize against it becoming runnable. | |
39a43640 | 2736 | */ |
63cae12b PZ |
2737 | if (task_curr(ctx->task) && !reprogram) { |
2738 | ret = -ESRCH; | |
2739 | goto unlock; | |
2740 | } | |
a096309b | 2741 | |
63cae12b | 2742 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2743 | } else if (task_ctx) { |
2744 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2745 | } |
b58f6b0d | 2746 | |
33801b94 | 2747 | #ifdef CONFIG_CGROUP_PERF |
2748 | if (is_cgroup_event(event)) { | |
2749 | /* | |
2750 | * If the current cgroup doesn't match the event's | |
2751 | * cgroup, we should not try to schedule it. | |
2752 | */ | |
2753 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2754 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2755 | event->cgrp->css.cgroup); | |
2756 | } | |
2757 | #endif | |
2758 | ||
63cae12b | 2759 | if (reprogram) { |
a096309b PZ |
2760 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2761 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2762 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2763 | } else { |
2764 | add_event_to_ctx(event, ctx); | |
2765 | } | |
2766 | ||
63b6da39 | 2767 | unlock: |
2c29ef0f | 2768 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2769 | |
a096309b | 2770 | return ret; |
0793a61d TG |
2771 | } |
2772 | ||
8a58ddae AS |
2773 | static bool exclusive_event_installable(struct perf_event *event, |
2774 | struct perf_event_context *ctx); | |
2775 | ||
0793a61d | 2776 | /* |
a096309b PZ |
2777 | * Attach a performance event to a context. |
2778 | * | |
2779 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2780 | */ |
2781 | static void | |
cdd6c482 IM |
2782 | perf_install_in_context(struct perf_event_context *ctx, |
2783 | struct perf_event *event, | |
0793a61d TG |
2784 | int cpu) |
2785 | { | |
a096309b | 2786 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2787 | |
fe4b04fa PZ |
2788 | lockdep_assert_held(&ctx->mutex); |
2789 | ||
8a58ddae AS |
2790 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2791 | ||
0cda4c02 YZ |
2792 | if (event->cpu != -1) |
2793 | event->cpu = cpu; | |
c3f00c70 | 2794 | |
0b8f1e2e PZ |
2795 | /* |
2796 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2797 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2798 | */ | |
2799 | smp_store_release(&event->ctx, ctx); | |
2800 | ||
db0503e4 PZ |
2801 | /* |
2802 | * perf_event_attr::disabled events will not run and can be initialized | |
2803 | * without IPI. Except when this is the first event for the context, in | |
2804 | * that case we need the magic of the IPI to set ctx->is_active. | |
2805 | * | |
2806 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2807 | * event will issue the IPI and reprogram the hardware. | |
2808 | */ | |
2809 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2810 | raw_spin_lock_irq(&ctx->lock); | |
2811 | if (ctx->task == TASK_TOMBSTONE) { | |
2812 | raw_spin_unlock_irq(&ctx->lock); | |
2813 | return; | |
2814 | } | |
2815 | add_event_to_ctx(event, ctx); | |
2816 | raw_spin_unlock_irq(&ctx->lock); | |
2817 | return; | |
2818 | } | |
2819 | ||
a096309b PZ |
2820 | if (!task) { |
2821 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2822 | return; | |
2823 | } | |
2824 | ||
2825 | /* | |
2826 | * Should not happen, we validate the ctx is still alive before calling. | |
2827 | */ | |
2828 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2829 | return; | |
2830 | ||
39a43640 PZ |
2831 | /* |
2832 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2833 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2834 | * |
2835 | * Instead we use task_curr(), which tells us if the task is running. | |
2836 | * However, since we use task_curr() outside of rq::lock, we can race | |
2837 | * against the actual state. This means the result can be wrong. | |
2838 | * | |
2839 | * If we get a false positive, we retry, this is harmless. | |
2840 | * | |
2841 | * If we get a false negative, things are complicated. If we are after | |
2842 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2843 | * value must be correct. If we're before, it doesn't matter since | |
2844 | * perf_event_context_sched_in() will program the counter. | |
2845 | * | |
2846 | * However, this hinges on the remote context switch having observed | |
2847 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2848 | * ctx::lock in perf_event_context_sched_in(). | |
2849 | * | |
2850 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2851 | * we know any future context switch of task must see the | |
2852 | * perf_event_ctpx[] store. | |
39a43640 | 2853 | */ |
63cae12b | 2854 | |
63b6da39 | 2855 | /* |
63cae12b PZ |
2856 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2857 | * task_cpu() load, such that if the IPI then does not find the task | |
2858 | * running, a future context switch of that task must observe the | |
2859 | * store. | |
63b6da39 | 2860 | */ |
63cae12b PZ |
2861 | smp_mb(); |
2862 | again: | |
2863 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2864 | return; |
2865 | ||
2866 | raw_spin_lock_irq(&ctx->lock); | |
2867 | task = ctx->task; | |
84c4e620 | 2868 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2869 | /* |
2870 | * Cannot happen because we already checked above (which also | |
2871 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2872 | * against perf_event_exit_task_context(). | |
2873 | */ | |
63b6da39 PZ |
2874 | raw_spin_unlock_irq(&ctx->lock); |
2875 | return; | |
2876 | } | |
39a43640 | 2877 | /* |
63cae12b PZ |
2878 | * If the task is not running, ctx->lock will avoid it becoming so, |
2879 | * thus we can safely install the event. | |
39a43640 | 2880 | */ |
63cae12b PZ |
2881 | if (task_curr(task)) { |
2882 | raw_spin_unlock_irq(&ctx->lock); | |
2883 | goto again; | |
2884 | } | |
2885 | add_event_to_ctx(event, ctx); | |
2886 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2887 | } |
2888 | ||
d859e29f | 2889 | /* |
cdd6c482 | 2890 | * Cross CPU call to enable a performance event |
d859e29f | 2891 | */ |
fae3fde6 PZ |
2892 | static void __perf_event_enable(struct perf_event *event, |
2893 | struct perf_cpu_context *cpuctx, | |
2894 | struct perf_event_context *ctx, | |
2895 | void *info) | |
04289bb9 | 2896 | { |
cdd6c482 | 2897 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2898 | struct perf_event_context *task_ctx; |
04289bb9 | 2899 | |
6e801e01 PZ |
2900 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2901 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2902 | return; |
3cbed429 | 2903 | |
bd2afa49 PZ |
2904 | if (ctx->is_active) |
2905 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2906 | ||
0d3d73aa | 2907 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2908 | |
fae3fde6 PZ |
2909 | if (!ctx->is_active) |
2910 | return; | |
2911 | ||
e5d1367f | 2912 | if (!event_filter_match(event)) { |
bd2afa49 | 2913 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2914 | return; |
e5d1367f | 2915 | } |
f4c4176f | 2916 | |
04289bb9 | 2917 | /* |
cdd6c482 | 2918 | * If the event is in a group and isn't the group leader, |
d859e29f | 2919 | * then don't put it on unless the group is on. |
04289bb9 | 2920 | */ |
bd2afa49 PZ |
2921 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2922 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2923 | return; |
bd2afa49 | 2924 | } |
fe4b04fa | 2925 | |
fae3fde6 PZ |
2926 | task_ctx = cpuctx->task_ctx; |
2927 | if (ctx->task) | |
2928 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2929 | |
487f05e1 | 2930 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2931 | } |
2932 | ||
d859e29f | 2933 | /* |
788faab7 | 2934 | * Enable an event. |
c93f7669 | 2935 | * |
cdd6c482 IM |
2936 | * If event->ctx is a cloned context, callers must make sure that |
2937 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2938 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2939 | * perf_event_for_each_child or perf_event_for_each as described |
2940 | * for perf_event_disable. | |
d859e29f | 2941 | */ |
f63a8daa | 2942 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2943 | { |
cdd6c482 | 2944 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2945 | |
7b648018 | 2946 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2947 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2948 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2949 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2950 | return; |
2951 | } | |
2952 | ||
d859e29f | 2953 | /* |
cdd6c482 | 2954 | * If the event is in error state, clear that first. |
7b648018 PZ |
2955 | * |
2956 | * That way, if we see the event in error state below, we know that it | |
2957 | * has gone back into error state, as distinct from the task having | |
2958 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2959 | */ |
cdd6c482 IM |
2960 | if (event->state == PERF_EVENT_STATE_ERROR) |
2961 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2962 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2963 | |
fae3fde6 | 2964 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2965 | } |
f63a8daa PZ |
2966 | |
2967 | /* | |
2968 | * See perf_event_disable(); | |
2969 | */ | |
2970 | void perf_event_enable(struct perf_event *event) | |
2971 | { | |
2972 | struct perf_event_context *ctx; | |
2973 | ||
2974 | ctx = perf_event_ctx_lock(event); | |
2975 | _perf_event_enable(event); | |
2976 | perf_event_ctx_unlock(event, ctx); | |
2977 | } | |
dcfce4a0 | 2978 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2979 | |
375637bc AS |
2980 | struct stop_event_data { |
2981 | struct perf_event *event; | |
2982 | unsigned int restart; | |
2983 | }; | |
2984 | ||
95ff4ca2 AS |
2985 | static int __perf_event_stop(void *info) |
2986 | { | |
375637bc AS |
2987 | struct stop_event_data *sd = info; |
2988 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2989 | |
375637bc | 2990 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2991 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2992 | return 0; | |
2993 | ||
2994 | /* matches smp_wmb() in event_sched_in() */ | |
2995 | smp_rmb(); | |
2996 | ||
2997 | /* | |
2998 | * There is a window with interrupts enabled before we get here, | |
2999 | * so we need to check again lest we try to stop another CPU's event. | |
3000 | */ | |
3001 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3002 | return -EAGAIN; | |
3003 | ||
3004 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3005 | ||
375637bc AS |
3006 | /* |
3007 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3008 | * but it is only used for events with AUX ring buffer, and such | |
3009 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3010 | * see comments in perf_aux_output_begin(). | |
3011 | * | |
788faab7 | 3012 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3013 | * while restarting. |
3014 | */ | |
3015 | if (sd->restart) | |
c9bbdd48 | 3016 | event->pmu->start(event, 0); |
375637bc | 3017 | |
95ff4ca2 AS |
3018 | return 0; |
3019 | } | |
3020 | ||
767ae086 | 3021 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3022 | { |
3023 | struct stop_event_data sd = { | |
3024 | .event = event, | |
767ae086 | 3025 | .restart = restart, |
375637bc AS |
3026 | }; |
3027 | int ret = 0; | |
3028 | ||
3029 | do { | |
3030 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3031 | return 0; | |
3032 | ||
3033 | /* matches smp_wmb() in event_sched_in() */ | |
3034 | smp_rmb(); | |
3035 | ||
3036 | /* | |
3037 | * We only want to restart ACTIVE events, so if the event goes | |
3038 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3039 | * fall through with ret==-ENXIO. | |
3040 | */ | |
3041 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3042 | __perf_event_stop, &sd); | |
3043 | } while (ret == -EAGAIN); | |
3044 | ||
3045 | return ret; | |
3046 | } | |
3047 | ||
3048 | /* | |
3049 | * In order to contain the amount of racy and tricky in the address filter | |
3050 | * configuration management, it is a two part process: | |
3051 | * | |
3052 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3053 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3054 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3055 | * (p2) when an event is scheduled in (pmu::add), it calls |
3056 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3057 | * if the generation has changed since the previous call. | |
3058 | * | |
3059 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3060 | * | |
3061 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3062 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3063 | * ioctl; | |
3064 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
3065 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
3066 | * for reading; | |
3067 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3068 | * of exec. | |
3069 | */ | |
3070 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3071 | { | |
3072 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3073 | ||
3074 | if (!has_addr_filter(event)) | |
3075 | return; | |
3076 | ||
3077 | raw_spin_lock(&ifh->lock); | |
3078 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3079 | event->pmu->addr_filters_sync(event); | |
3080 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3081 | } | |
3082 | raw_spin_unlock(&ifh->lock); | |
3083 | } | |
3084 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3085 | ||
f63a8daa | 3086 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3087 | { |
2023b359 | 3088 | /* |
cdd6c482 | 3089 | * not supported on inherited events |
2023b359 | 3090 | */ |
2e939d1d | 3091 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3092 | return -EINVAL; |
3093 | ||
cdd6c482 | 3094 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3095 | _perf_event_enable(event); |
2023b359 PZ |
3096 | |
3097 | return 0; | |
79f14641 | 3098 | } |
f63a8daa PZ |
3099 | |
3100 | /* | |
3101 | * See perf_event_disable() | |
3102 | */ | |
3103 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3104 | { | |
3105 | struct perf_event_context *ctx; | |
3106 | int ret; | |
3107 | ||
3108 | ctx = perf_event_ctx_lock(event); | |
3109 | ret = _perf_event_refresh(event, refresh); | |
3110 | perf_event_ctx_unlock(event, ctx); | |
3111 | ||
3112 | return ret; | |
3113 | } | |
26ca5c11 | 3114 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3115 | |
32ff77e8 MC |
3116 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3117 | struct perf_event_attr *attr) | |
3118 | { | |
3119 | int err; | |
3120 | ||
3121 | _perf_event_disable(bp); | |
3122 | ||
3123 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3124 | |
bf06278c | 3125 | if (!bp->attr.disabled) |
32ff77e8 | 3126 | _perf_event_enable(bp); |
bf06278c JO |
3127 | |
3128 | return err; | |
32ff77e8 MC |
3129 | } |
3130 | ||
3131 | static int perf_event_modify_attr(struct perf_event *event, | |
3132 | struct perf_event_attr *attr) | |
3133 | { | |
3134 | if (event->attr.type != attr->type) | |
3135 | return -EINVAL; | |
3136 | ||
3137 | switch (event->attr.type) { | |
3138 | case PERF_TYPE_BREAKPOINT: | |
3139 | return perf_event_modify_breakpoint(event, attr); | |
3140 | default: | |
3141 | /* Place holder for future additions. */ | |
3142 | return -EOPNOTSUPP; | |
3143 | } | |
3144 | } | |
3145 | ||
5b0311e1 FW |
3146 | static void ctx_sched_out(struct perf_event_context *ctx, |
3147 | struct perf_cpu_context *cpuctx, | |
3148 | enum event_type_t event_type) | |
235c7fc7 | 3149 | { |
6668128a | 3150 | struct perf_event *event, *tmp; |
db24d33e | 3151 | int is_active = ctx->is_active; |
235c7fc7 | 3152 | |
c994d613 | 3153 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3154 | |
39a43640 PZ |
3155 | if (likely(!ctx->nr_events)) { |
3156 | /* | |
3157 | * See __perf_remove_from_context(). | |
3158 | */ | |
3159 | WARN_ON_ONCE(ctx->is_active); | |
3160 | if (ctx->task) | |
3161 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3162 | return; |
39a43640 PZ |
3163 | } |
3164 | ||
db24d33e | 3165 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3166 | if (!(ctx->is_active & EVENT_ALL)) |
3167 | ctx->is_active = 0; | |
3168 | ||
63e30d3e PZ |
3169 | if (ctx->task) { |
3170 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3171 | if (!ctx->is_active) | |
3172 | cpuctx->task_ctx = NULL; | |
3173 | } | |
facc4307 | 3174 | |
8fdc6539 PZ |
3175 | /* |
3176 | * Always update time if it was set; not only when it changes. | |
3177 | * Otherwise we can 'forget' to update time for any but the last | |
3178 | * context we sched out. For example: | |
3179 | * | |
3180 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3181 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3182 | * | |
3183 | * would only update time for the pinned events. | |
3184 | */ | |
3cbaa590 PZ |
3185 | if (is_active & EVENT_TIME) { |
3186 | /* update (and stop) ctx time */ | |
3187 | update_context_time(ctx); | |
3188 | update_cgrp_time_from_cpuctx(cpuctx); | |
3189 | } | |
3190 | ||
8fdc6539 PZ |
3191 | is_active ^= ctx->is_active; /* changed bits */ |
3192 | ||
3cbaa590 | 3193 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3194 | return; |
5b0311e1 | 3195 | |
075e0b00 | 3196 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3197 | if (is_active & EVENT_PINNED) { |
6668128a | 3198 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3199 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3200 | } |
889ff015 | 3201 | |
3cbaa590 | 3202 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3203 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3204 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3205 | |
3206 | /* | |
3207 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3208 | * rotate_necessary, is will be reset by | |
3209 | * ctx_flexible_sched_in() when needed. | |
3210 | */ | |
3211 | ctx->rotate_necessary = 0; | |
9ed6060d | 3212 | } |
1b9a644f | 3213 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3214 | } |
3215 | ||
564c2b21 | 3216 | /* |
5a3126d4 PZ |
3217 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3218 | * cloned from the same version of the same context. | |
3219 | * | |
3220 | * Equivalence is measured using a generation number in the context that is | |
3221 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3222 | * and list_del_event(). | |
564c2b21 | 3223 | */ |
cdd6c482 IM |
3224 | static int context_equiv(struct perf_event_context *ctx1, |
3225 | struct perf_event_context *ctx2) | |
564c2b21 | 3226 | { |
211de6eb PZ |
3227 | lockdep_assert_held(&ctx1->lock); |
3228 | lockdep_assert_held(&ctx2->lock); | |
3229 | ||
5a3126d4 PZ |
3230 | /* Pinning disables the swap optimization */ |
3231 | if (ctx1->pin_count || ctx2->pin_count) | |
3232 | return 0; | |
3233 | ||
3234 | /* If ctx1 is the parent of ctx2 */ | |
3235 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3236 | return 1; | |
3237 | ||
3238 | /* If ctx2 is the parent of ctx1 */ | |
3239 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3240 | return 1; | |
3241 | ||
3242 | /* | |
3243 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3244 | * hierarchy, see perf_event_init_context(). | |
3245 | */ | |
3246 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3247 | ctx1->parent_gen == ctx2->parent_gen) | |
3248 | return 1; | |
3249 | ||
3250 | /* Unmatched */ | |
3251 | return 0; | |
564c2b21 PM |
3252 | } |
3253 | ||
cdd6c482 IM |
3254 | static void __perf_event_sync_stat(struct perf_event *event, |
3255 | struct perf_event *next_event) | |
bfbd3381 PZ |
3256 | { |
3257 | u64 value; | |
3258 | ||
cdd6c482 | 3259 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3260 | return; |
3261 | ||
3262 | /* | |
cdd6c482 | 3263 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3264 | * because we're in the middle of a context switch and have IRQs |
3265 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3266 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3267 | * don't need to use it. |
3268 | */ | |
0d3d73aa | 3269 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3270 | event->pmu->read(event); |
bfbd3381 | 3271 | |
0d3d73aa | 3272 | perf_event_update_time(event); |
bfbd3381 PZ |
3273 | |
3274 | /* | |
cdd6c482 | 3275 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3276 | * values when we flip the contexts. |
3277 | */ | |
e7850595 PZ |
3278 | value = local64_read(&next_event->count); |
3279 | value = local64_xchg(&event->count, value); | |
3280 | local64_set(&next_event->count, value); | |
bfbd3381 | 3281 | |
cdd6c482 IM |
3282 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3283 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3284 | |
bfbd3381 | 3285 | /* |
19d2e755 | 3286 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3287 | */ |
cdd6c482 IM |
3288 | perf_event_update_userpage(event); |
3289 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3290 | } |
3291 | ||
cdd6c482 IM |
3292 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3293 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3294 | { |
cdd6c482 | 3295 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3296 | |
3297 | if (!ctx->nr_stat) | |
3298 | return; | |
3299 | ||
02ffdbc8 PZ |
3300 | update_context_time(ctx); |
3301 | ||
cdd6c482 IM |
3302 | event = list_first_entry(&ctx->event_list, |
3303 | struct perf_event, event_entry); | |
bfbd3381 | 3304 | |
cdd6c482 IM |
3305 | next_event = list_first_entry(&next_ctx->event_list, |
3306 | struct perf_event, event_entry); | |
bfbd3381 | 3307 | |
cdd6c482 IM |
3308 | while (&event->event_entry != &ctx->event_list && |
3309 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3310 | |
cdd6c482 | 3311 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3312 | |
cdd6c482 IM |
3313 | event = list_next_entry(event, event_entry); |
3314 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3315 | } |
3316 | } | |
3317 | ||
fe4b04fa PZ |
3318 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3319 | struct task_struct *next) | |
0793a61d | 3320 | { |
8dc85d54 | 3321 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3322 | struct perf_event_context *next_ctx; |
5a3126d4 | 3323 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3324 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3325 | int do_switch = 1; |
0793a61d | 3326 | |
108b02cf PZ |
3327 | if (likely(!ctx)) |
3328 | return; | |
10989fb2 | 3329 | |
108b02cf PZ |
3330 | cpuctx = __get_cpu_context(ctx); |
3331 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3332 | return; |
3333 | ||
c93f7669 | 3334 | rcu_read_lock(); |
8dc85d54 | 3335 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3336 | if (!next_ctx) |
3337 | goto unlock; | |
3338 | ||
3339 | parent = rcu_dereference(ctx->parent_ctx); | |
3340 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3341 | ||
3342 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3343 | if (!parent && !next_parent) |
5a3126d4 PZ |
3344 | goto unlock; |
3345 | ||
3346 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3347 | /* |
3348 | * Looks like the two contexts are clones, so we might be | |
3349 | * able to optimize the context switch. We lock both | |
3350 | * contexts and check that they are clones under the | |
3351 | * lock (including re-checking that neither has been | |
3352 | * uncloned in the meantime). It doesn't matter which | |
3353 | * order we take the locks because no other cpu could | |
3354 | * be trying to lock both of these tasks. | |
3355 | */ | |
e625cce1 TG |
3356 | raw_spin_lock(&ctx->lock); |
3357 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3358 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 AB |
3359 | struct pmu *pmu = ctx->pmu; |
3360 | ||
63b6da39 PZ |
3361 | WRITE_ONCE(ctx->task, next); |
3362 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3363 | |
c2b98a86 AB |
3364 | /* |
3365 | * PMU specific parts of task perf context can require | |
3366 | * additional synchronization. As an example of such | |
3367 | * synchronization see implementation details of Intel | |
3368 | * LBR call stack data profiling; | |
3369 | */ | |
3370 | if (pmu->swap_task_ctx) | |
3371 | pmu->swap_task_ctx(ctx, next_ctx); | |
3372 | else | |
3373 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3374 | |
63b6da39 PZ |
3375 | /* |
3376 | * RCU_INIT_POINTER here is safe because we've not | |
3377 | * modified the ctx and the above modification of | |
3378 | * ctx->task and ctx->task_ctx_data are immaterial | |
3379 | * since those values are always verified under | |
3380 | * ctx->lock which we're now holding. | |
3381 | */ | |
3382 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3383 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3384 | ||
c93f7669 | 3385 | do_switch = 0; |
bfbd3381 | 3386 | |
cdd6c482 | 3387 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3388 | } |
e625cce1 TG |
3389 | raw_spin_unlock(&next_ctx->lock); |
3390 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3391 | } |
5a3126d4 | 3392 | unlock: |
c93f7669 | 3393 | rcu_read_unlock(); |
564c2b21 | 3394 | |
c93f7669 | 3395 | if (do_switch) { |
facc4307 | 3396 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3397 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3398 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3399 | } |
0793a61d TG |
3400 | } |
3401 | ||
e48c1788 PZ |
3402 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3403 | ||
ba532500 YZ |
3404 | void perf_sched_cb_dec(struct pmu *pmu) |
3405 | { | |
e48c1788 PZ |
3406 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3407 | ||
ba532500 | 3408 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3409 | |
3410 | if (!--cpuctx->sched_cb_usage) | |
3411 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3412 | } |
3413 | ||
e48c1788 | 3414 | |
ba532500 YZ |
3415 | void perf_sched_cb_inc(struct pmu *pmu) |
3416 | { | |
e48c1788 PZ |
3417 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3418 | ||
3419 | if (!cpuctx->sched_cb_usage++) | |
3420 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3421 | ||
ba532500 YZ |
3422 | this_cpu_inc(perf_sched_cb_usages); |
3423 | } | |
3424 | ||
3425 | /* | |
3426 | * This function provides the context switch callback to the lower code | |
3427 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3428 | * |
3429 | * This callback is relevant even to per-cpu events; for example multi event | |
3430 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3431 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3432 | */ |
3433 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3434 | struct task_struct *next, | |
3435 | bool sched_in) | |
3436 | { | |
3437 | struct perf_cpu_context *cpuctx; | |
3438 | struct pmu *pmu; | |
ba532500 YZ |
3439 | |
3440 | if (prev == next) | |
3441 | return; | |
3442 | ||
e48c1788 | 3443 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3444 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3445 | |
e48c1788 PZ |
3446 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3447 | continue; | |
ba532500 | 3448 | |
e48c1788 PZ |
3449 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3450 | perf_pmu_disable(pmu); | |
ba532500 | 3451 | |
e48c1788 | 3452 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3453 | |
e48c1788 PZ |
3454 | perf_pmu_enable(pmu); |
3455 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3456 | } |
ba532500 YZ |
3457 | } |
3458 | ||
45ac1403 AH |
3459 | static void perf_event_switch(struct task_struct *task, |
3460 | struct task_struct *next_prev, bool sched_in); | |
3461 | ||
8dc85d54 PZ |
3462 | #define for_each_task_context_nr(ctxn) \ |
3463 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3464 | ||
3465 | /* | |
3466 | * Called from scheduler to remove the events of the current task, | |
3467 | * with interrupts disabled. | |
3468 | * | |
3469 | * We stop each event and update the event value in event->count. | |
3470 | * | |
3471 | * This does not protect us against NMI, but disable() | |
3472 | * sets the disabled bit in the control field of event _before_ | |
3473 | * accessing the event control register. If a NMI hits, then it will | |
3474 | * not restart the event. | |
3475 | */ | |
ab0cce56 JO |
3476 | void __perf_event_task_sched_out(struct task_struct *task, |
3477 | struct task_struct *next) | |
8dc85d54 PZ |
3478 | { |
3479 | int ctxn; | |
3480 | ||
ba532500 YZ |
3481 | if (__this_cpu_read(perf_sched_cb_usages)) |
3482 | perf_pmu_sched_task(task, next, false); | |
3483 | ||
45ac1403 AH |
3484 | if (atomic_read(&nr_switch_events)) |
3485 | perf_event_switch(task, next, false); | |
3486 | ||
8dc85d54 PZ |
3487 | for_each_task_context_nr(ctxn) |
3488 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3489 | |
3490 | /* | |
3491 | * if cgroup events exist on this CPU, then we need | |
3492 | * to check if we have to switch out PMU state. | |
3493 | * cgroup event are system-wide mode only | |
3494 | */ | |
4a32fea9 | 3495 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3496 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3497 | } |
3498 | ||
5b0311e1 FW |
3499 | /* |
3500 | * Called with IRQs disabled | |
3501 | */ | |
3502 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3503 | enum event_type_t event_type) | |
3504 | { | |
3505 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3506 | } |
3507 | ||
6eef8a71 | 3508 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3509 | { |
6eef8a71 IR |
3510 | const struct perf_event *le = l, *re = r; |
3511 | ||
3512 | return le->group_index < re->group_index; | |
3513 | } | |
3514 | ||
3515 | static void swap_ptr(void *l, void *r) | |
3516 | { | |
3517 | void **lp = l, **rp = r; | |
3518 | ||
3519 | swap(*lp, *rp); | |
3520 | } | |
3521 | ||
3522 | static const struct min_heap_callbacks perf_min_heap = { | |
3523 | .elem_size = sizeof(struct perf_event *), | |
3524 | .less = perf_less_group_idx, | |
3525 | .swp = swap_ptr, | |
3526 | }; | |
3527 | ||
3528 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3529 | { | |
3530 | struct perf_event **itrs = heap->data; | |
3531 | ||
3532 | if (event) { | |
3533 | itrs[heap->nr] = event; | |
3534 | heap->nr++; | |
3535 | } | |
3536 | } | |
3537 | ||
836196be IR |
3538 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3539 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3540 | int (*func)(struct perf_event *, void *), |
3541 | void *data) | |
3542 | { | |
95ed6c70 IR |
3543 | #ifdef CONFIG_CGROUP_PERF |
3544 | struct cgroup_subsys_state *css = NULL; | |
3545 | #endif | |
6eef8a71 IR |
3546 | /* Space for per CPU and/or any CPU event iterators. */ |
3547 | struct perf_event *itrs[2]; | |
836196be IR |
3548 | struct min_heap event_heap; |
3549 | struct perf_event **evt; | |
1cac7b1a | 3550 | int ret; |
8e1a2031 | 3551 | |
836196be IR |
3552 | if (cpuctx) { |
3553 | event_heap = (struct min_heap){ | |
3554 | .data = cpuctx->heap, | |
3555 | .nr = 0, | |
3556 | .size = cpuctx->heap_size, | |
3557 | }; | |
c2283c93 IR |
3558 | |
3559 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3560 | |
3561 | #ifdef CONFIG_CGROUP_PERF | |
3562 | if (cpuctx->cgrp) | |
3563 | css = &cpuctx->cgrp->css; | |
3564 | #endif | |
836196be IR |
3565 | } else { |
3566 | event_heap = (struct min_heap){ | |
3567 | .data = itrs, | |
3568 | .nr = 0, | |
3569 | .size = ARRAY_SIZE(itrs), | |
3570 | }; | |
3571 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3572 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3573 | } |
3574 | evt = event_heap.data; | |
3575 | ||
95ed6c70 IR |
3576 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3577 | ||
3578 | #ifdef CONFIG_CGROUP_PERF | |
3579 | for (; css; css = css->parent) | |
3580 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3581 | #endif | |
1cac7b1a | 3582 | |
6eef8a71 | 3583 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3584 | |
6eef8a71 | 3585 | while (event_heap.nr) { |
1cac7b1a PZ |
3586 | ret = func(*evt, data); |
3587 | if (ret) | |
3588 | return ret; | |
3589 | ||
3590 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3591 | if (*evt) |
3592 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3593 | else | |
3594 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3595 | } |
0793a61d | 3596 | |
1cac7b1a PZ |
3597 | return 0; |
3598 | } | |
3599 | ||
ab6f824c | 3600 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3601 | { |
2c2366c7 PZ |
3602 | struct perf_event_context *ctx = event->ctx; |
3603 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3604 | int *can_add_hw = data; | |
ab6f824c | 3605 | |
1cac7b1a PZ |
3606 | if (event->state <= PERF_EVENT_STATE_OFF) |
3607 | return 0; | |
3608 | ||
3609 | if (!event_filter_match(event)) | |
3610 | return 0; | |
3611 | ||
2c2366c7 PZ |
3612 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3613 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3614 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3615 | } |
1cac7b1a | 3616 | |
ab6f824c PZ |
3617 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3618 | if (event->attr.pinned) | |
3619 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
1cac7b1a | 3620 | |
2c2366c7 PZ |
3621 | *can_add_hw = 0; |
3622 | ctx->rotate_necessary = 1; | |
3b6f9e5c | 3623 | } |
1cac7b1a PZ |
3624 | |
3625 | return 0; | |
5b0311e1 FW |
3626 | } |
3627 | ||
3628 | static void | |
1cac7b1a PZ |
3629 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3630 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3631 | { |
2c2366c7 | 3632 | int can_add_hw = 1; |
3b6f9e5c | 3633 | |
836196be IR |
3634 | if (ctx != &cpuctx->ctx) |
3635 | cpuctx = NULL; | |
3636 | ||
3637 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3638 | smp_processor_id(), |
2c2366c7 | 3639 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3640 | } |
8e1a2031 | 3641 | |
1cac7b1a PZ |
3642 | static void |
3643 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3644 | struct perf_cpu_context *cpuctx) | |
3645 | { | |
2c2366c7 | 3646 | int can_add_hw = 1; |
0793a61d | 3647 | |
836196be IR |
3648 | if (ctx != &cpuctx->ctx) |
3649 | cpuctx = NULL; | |
3650 | ||
3651 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3652 | smp_processor_id(), |
2c2366c7 | 3653 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3654 | } |
3655 | ||
3656 | static void | |
3657 | ctx_sched_in(struct perf_event_context *ctx, | |
3658 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3659 | enum event_type_t event_type, |
3660 | struct task_struct *task) | |
5b0311e1 | 3661 | { |
db24d33e | 3662 | int is_active = ctx->is_active; |
c994d613 PZ |
3663 | u64 now; |
3664 | ||
3665 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3666 | |
5b0311e1 | 3667 | if (likely(!ctx->nr_events)) |
facc4307 | 3668 | return; |
5b0311e1 | 3669 | |
3cbaa590 | 3670 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3671 | if (ctx->task) { |
3672 | if (!is_active) | |
3673 | cpuctx->task_ctx = ctx; | |
3674 | else | |
3675 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3676 | } | |
3677 | ||
3cbaa590 PZ |
3678 | is_active ^= ctx->is_active; /* changed bits */ |
3679 | ||
3680 | if (is_active & EVENT_TIME) { | |
3681 | /* start ctx time */ | |
3682 | now = perf_clock(); | |
3683 | ctx->timestamp = now; | |
3684 | perf_cgroup_set_timestamp(task, ctx); | |
3685 | } | |
3686 | ||
5b0311e1 FW |
3687 | /* |
3688 | * First go through the list and put on any pinned groups | |
3689 | * in order to give them the best chance of going on. | |
3690 | */ | |
3cbaa590 | 3691 | if (is_active & EVENT_PINNED) |
6e37738a | 3692 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3693 | |
3694 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3695 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3696 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3697 | } |
3698 | ||
329c0e01 | 3699 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3700 | enum event_type_t event_type, |
3701 | struct task_struct *task) | |
329c0e01 FW |
3702 | { |
3703 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3704 | ||
e5d1367f | 3705 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3706 | } |
3707 | ||
e5d1367f SE |
3708 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3709 | struct task_struct *task) | |
235c7fc7 | 3710 | { |
108b02cf | 3711 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3712 | |
108b02cf | 3713 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3714 | if (cpuctx->task_ctx == ctx) |
3715 | return; | |
3716 | ||
facc4307 | 3717 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3718 | /* |
3719 | * We must check ctx->nr_events while holding ctx->lock, such | |
3720 | * that we serialize against perf_install_in_context(). | |
3721 | */ | |
3722 | if (!ctx->nr_events) | |
3723 | goto unlock; | |
3724 | ||
1b9a644f | 3725 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3726 | /* |
3727 | * We want to keep the following priority order: | |
3728 | * cpu pinned (that don't need to move), task pinned, | |
3729 | * cpu flexible, task flexible. | |
fe45bafb AS |
3730 | * |
3731 | * However, if task's ctx is not carrying any pinned | |
3732 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3733 | */ |
8e1a2031 | 3734 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3735 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3736 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3737 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3738 | |
3739 | unlock: | |
facc4307 | 3740 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3741 | } |
3742 | ||
8dc85d54 PZ |
3743 | /* |
3744 | * Called from scheduler to add the events of the current task | |
3745 | * with interrupts disabled. | |
3746 | * | |
3747 | * We restore the event value and then enable it. | |
3748 | * | |
3749 | * This does not protect us against NMI, but enable() | |
3750 | * sets the enabled bit in the control field of event _before_ | |
3751 | * accessing the event control register. If a NMI hits, then it will | |
3752 | * keep the event running. | |
3753 | */ | |
ab0cce56 JO |
3754 | void __perf_event_task_sched_in(struct task_struct *prev, |
3755 | struct task_struct *task) | |
8dc85d54 PZ |
3756 | { |
3757 | struct perf_event_context *ctx; | |
3758 | int ctxn; | |
3759 | ||
7e41d177 PZ |
3760 | /* |
3761 | * If cgroup events exist on this CPU, then we need to check if we have | |
3762 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3763 | * | |
3764 | * Since cgroup events are CPU events, we must schedule these in before | |
3765 | * we schedule in the task events. | |
3766 | */ | |
3767 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3768 | perf_cgroup_sched_in(prev, task); | |
3769 | ||
8dc85d54 PZ |
3770 | for_each_task_context_nr(ctxn) { |
3771 | ctx = task->perf_event_ctxp[ctxn]; | |
3772 | if (likely(!ctx)) | |
3773 | continue; | |
3774 | ||
e5d1367f | 3775 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3776 | } |
d010b332 | 3777 | |
45ac1403 AH |
3778 | if (atomic_read(&nr_switch_events)) |
3779 | perf_event_switch(task, prev, true); | |
3780 | ||
ba532500 YZ |
3781 | if (__this_cpu_read(perf_sched_cb_usages)) |
3782 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3783 | } |
3784 | ||
abd50713 PZ |
3785 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3786 | { | |
3787 | u64 frequency = event->attr.sample_freq; | |
3788 | u64 sec = NSEC_PER_SEC; | |
3789 | u64 divisor, dividend; | |
3790 | ||
3791 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3792 | ||
3793 | count_fls = fls64(count); | |
3794 | nsec_fls = fls64(nsec); | |
3795 | frequency_fls = fls64(frequency); | |
3796 | sec_fls = 30; | |
3797 | ||
3798 | /* | |
3799 | * We got @count in @nsec, with a target of sample_freq HZ | |
3800 | * the target period becomes: | |
3801 | * | |
3802 | * @count * 10^9 | |
3803 | * period = ------------------- | |
3804 | * @nsec * sample_freq | |
3805 | * | |
3806 | */ | |
3807 | ||
3808 | /* | |
3809 | * Reduce accuracy by one bit such that @a and @b converge | |
3810 | * to a similar magnitude. | |
3811 | */ | |
fe4b04fa | 3812 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3813 | do { \ |
3814 | if (a##_fls > b##_fls) { \ | |
3815 | a >>= 1; \ | |
3816 | a##_fls--; \ | |
3817 | } else { \ | |
3818 | b >>= 1; \ | |
3819 | b##_fls--; \ | |
3820 | } \ | |
3821 | } while (0) | |
3822 | ||
3823 | /* | |
3824 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3825 | * the other, so that finally we can do a u64/u64 division. | |
3826 | */ | |
3827 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3828 | REDUCE_FLS(nsec, frequency); | |
3829 | REDUCE_FLS(sec, count); | |
3830 | } | |
3831 | ||
3832 | if (count_fls + sec_fls > 64) { | |
3833 | divisor = nsec * frequency; | |
3834 | ||
3835 | while (count_fls + sec_fls > 64) { | |
3836 | REDUCE_FLS(count, sec); | |
3837 | divisor >>= 1; | |
3838 | } | |
3839 | ||
3840 | dividend = count * sec; | |
3841 | } else { | |
3842 | dividend = count * sec; | |
3843 | ||
3844 | while (nsec_fls + frequency_fls > 64) { | |
3845 | REDUCE_FLS(nsec, frequency); | |
3846 | dividend >>= 1; | |
3847 | } | |
3848 | ||
3849 | divisor = nsec * frequency; | |
3850 | } | |
3851 | ||
f6ab91ad PZ |
3852 | if (!divisor) |
3853 | return dividend; | |
3854 | ||
abd50713 PZ |
3855 | return div64_u64(dividend, divisor); |
3856 | } | |
3857 | ||
e050e3f0 SE |
3858 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3859 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3860 | ||
f39d47ff | 3861 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3862 | { |
cdd6c482 | 3863 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3864 | s64 period, sample_period; |
bd2b5b12 PZ |
3865 | s64 delta; |
3866 | ||
abd50713 | 3867 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3868 | |
3869 | delta = (s64)(period - hwc->sample_period); | |
3870 | delta = (delta + 7) / 8; /* low pass filter */ | |
3871 | ||
3872 | sample_period = hwc->sample_period + delta; | |
3873 | ||
3874 | if (!sample_period) | |
3875 | sample_period = 1; | |
3876 | ||
bd2b5b12 | 3877 | hwc->sample_period = sample_period; |
abd50713 | 3878 | |
e7850595 | 3879 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3880 | if (disable) |
3881 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3882 | ||
e7850595 | 3883 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3884 | |
3885 | if (disable) | |
3886 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3887 | } |
bd2b5b12 PZ |
3888 | } |
3889 | ||
e050e3f0 SE |
3890 | /* |
3891 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3892 | * events. At the same time, make sure, having freq events does not change | |
3893 | * the rate of unthrottling as that would introduce bias. | |
3894 | */ | |
3895 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3896 | int needs_unthr) | |
60db5e09 | 3897 | { |
cdd6c482 IM |
3898 | struct perf_event *event; |
3899 | struct hw_perf_event *hwc; | |
e050e3f0 | 3900 | u64 now, period = TICK_NSEC; |
abd50713 | 3901 | s64 delta; |
60db5e09 | 3902 | |
e050e3f0 SE |
3903 | /* |
3904 | * only need to iterate over all events iff: | |
3905 | * - context have events in frequency mode (needs freq adjust) | |
3906 | * - there are events to unthrottle on this cpu | |
3907 | */ | |
3908 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3909 | return; |
3910 | ||
e050e3f0 | 3911 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3912 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3913 | |
03541f8b | 3914 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3915 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3916 | continue; |
3917 | ||
5632ab12 | 3918 | if (!event_filter_match(event)) |
5d27c23d PZ |
3919 | continue; |
3920 | ||
44377277 AS |
3921 | perf_pmu_disable(event->pmu); |
3922 | ||
cdd6c482 | 3923 | hwc = &event->hw; |
6a24ed6c | 3924 | |
ae23bff1 | 3925 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3926 | hwc->interrupts = 0; |
cdd6c482 | 3927 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3928 | event->pmu->start(event, 0); |
a78ac325 PZ |
3929 | } |
3930 | ||
cdd6c482 | 3931 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3932 | goto next; |
60db5e09 | 3933 | |
e050e3f0 SE |
3934 | /* |
3935 | * stop the event and update event->count | |
3936 | */ | |
3937 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3938 | ||
e7850595 | 3939 | now = local64_read(&event->count); |
abd50713 PZ |
3940 | delta = now - hwc->freq_count_stamp; |
3941 | hwc->freq_count_stamp = now; | |
60db5e09 | 3942 | |
e050e3f0 SE |
3943 | /* |
3944 | * restart the event | |
3945 | * reload only if value has changed | |
f39d47ff SE |
3946 | * we have stopped the event so tell that |
3947 | * to perf_adjust_period() to avoid stopping it | |
3948 | * twice. | |
e050e3f0 | 3949 | */ |
abd50713 | 3950 | if (delta > 0) |
f39d47ff | 3951 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3952 | |
3953 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3954 | next: |
3955 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3956 | } |
e050e3f0 | 3957 | |
f39d47ff | 3958 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3959 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3960 | } |
3961 | ||
235c7fc7 | 3962 | /* |
8703a7cf | 3963 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3964 | */ |
8703a7cf | 3965 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3966 | { |
dddd3379 TG |
3967 | /* |
3968 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3969 | * disabled by the inheritance code. | |
3970 | */ | |
8703a7cf PZ |
3971 | if (ctx->rotate_disable) |
3972 | return; | |
8e1a2031 | 3973 | |
8703a7cf PZ |
3974 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3975 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3976 | } |
3977 | ||
7fa343b7 | 3978 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 3979 | static inline struct perf_event * |
7fa343b7 | 3980 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 3981 | { |
7fa343b7 SL |
3982 | struct perf_event *event; |
3983 | ||
3984 | /* pick the first active flexible event */ | |
3985 | event = list_first_entry_or_null(&ctx->flexible_active, | |
3986 | struct perf_event, active_list); | |
3987 | ||
3988 | /* if no active flexible event, pick the first event */ | |
3989 | if (!event) { | |
3990 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
3991 | typeof(*event), group_node); | |
3992 | } | |
3993 | ||
90c91dfb PZ |
3994 | /* |
3995 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
3996 | * finds there are unschedulable events, it will set it again. | |
3997 | */ | |
3998 | ctx->rotate_necessary = 0; | |
3999 | ||
7fa343b7 | 4000 | return event; |
8d5bce0c PZ |
4001 | } |
4002 | ||
4003 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4004 | { | |
4005 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4006 | struct perf_event_context *task_ctx = NULL; |
4007 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4008 | |
4009 | /* | |
4010 | * Since we run this from IRQ context, nobody can install new | |
4011 | * events, thus the event count values are stable. | |
4012 | */ | |
7fc23a53 | 4013 | |
fd7d5517 IR |
4014 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4015 | task_ctx = cpuctx->task_ctx; | |
4016 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4017 | |
8d5bce0c PZ |
4018 | if (!(cpu_rotate || task_rotate)) |
4019 | return false; | |
0f5a2601 | 4020 | |
facc4307 | 4021 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4022 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4023 | |
8d5bce0c | 4024 | if (task_rotate) |
7fa343b7 | 4025 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4026 | if (cpu_rotate) |
7fa343b7 | 4027 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4028 | |
8d5bce0c PZ |
4029 | /* |
4030 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4031 | * and then, if needed CPU flexible. | |
4032 | */ | |
fd7d5517 IR |
4033 | if (task_event || (task_ctx && cpu_event)) |
4034 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4035 | if (cpu_event) |
4036 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4037 | |
8d5bce0c | 4038 | if (task_event) |
fd7d5517 | 4039 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4040 | if (cpu_event) |
4041 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4042 | |
fd7d5517 | 4043 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4044 | |
0f5a2601 PZ |
4045 | perf_pmu_enable(cpuctx->ctx.pmu); |
4046 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4047 | |
8d5bce0c | 4048 | return true; |
e9d2b064 PZ |
4049 | } |
4050 | ||
4051 | void perf_event_task_tick(void) | |
4052 | { | |
2fde4f94 MR |
4053 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4054 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4055 | int throttled; |
b5ab4cd5 | 4056 | |
16444645 | 4057 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4058 | |
e050e3f0 SE |
4059 | __this_cpu_inc(perf_throttled_seq); |
4060 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4061 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4062 | |
2fde4f94 | 4063 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4064 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4065 | } |
4066 | ||
889ff015 FW |
4067 | static int event_enable_on_exec(struct perf_event *event, |
4068 | struct perf_event_context *ctx) | |
4069 | { | |
4070 | if (!event->attr.enable_on_exec) | |
4071 | return 0; | |
4072 | ||
4073 | event->attr.enable_on_exec = 0; | |
4074 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4075 | return 0; | |
4076 | ||
0d3d73aa | 4077 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4078 | |
4079 | return 1; | |
4080 | } | |
4081 | ||
57e7986e | 4082 | /* |
cdd6c482 | 4083 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4084 | * This expects task == current. |
4085 | */ | |
c1274499 | 4086 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4087 | { |
c1274499 | 4088 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4089 | enum event_type_t event_type = 0; |
3e349507 | 4090 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4091 | struct perf_event *event; |
57e7986e PM |
4092 | unsigned long flags; |
4093 | int enabled = 0; | |
4094 | ||
4095 | local_irq_save(flags); | |
c1274499 | 4096 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4097 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4098 | goto out; |
4099 | ||
3e349507 PZ |
4100 | cpuctx = __get_cpu_context(ctx); |
4101 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4102 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4103 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4104 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4105 | event_type |= get_event_type(event); |
4106 | } | |
57e7986e PM |
4107 | |
4108 | /* | |
3e349507 | 4109 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4110 | */ |
3e349507 | 4111 | if (enabled) { |
211de6eb | 4112 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4113 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4114 | } else { |
4115 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4116 | } |
4117 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4118 | |
9ed6060d | 4119 | out: |
57e7986e | 4120 | local_irq_restore(flags); |
211de6eb PZ |
4121 | |
4122 | if (clone_ctx) | |
4123 | put_ctx(clone_ctx); | |
57e7986e PM |
4124 | } |
4125 | ||
0492d4c5 PZ |
4126 | struct perf_read_data { |
4127 | struct perf_event *event; | |
4128 | bool group; | |
7d88962e | 4129 | int ret; |
0492d4c5 PZ |
4130 | }; |
4131 | ||
451d24d1 | 4132 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4133 | { |
d6a2f903 DCC |
4134 | u16 local_pkg, event_pkg; |
4135 | ||
4136 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4137 | int local_cpu = smp_processor_id(); |
4138 | ||
4139 | event_pkg = topology_physical_package_id(event_cpu); | |
4140 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4141 | |
4142 | if (event_pkg == local_pkg) | |
4143 | return local_cpu; | |
4144 | } | |
4145 | ||
4146 | return event_cpu; | |
4147 | } | |
4148 | ||
0793a61d | 4149 | /* |
cdd6c482 | 4150 | * Cross CPU call to read the hardware event |
0793a61d | 4151 | */ |
cdd6c482 | 4152 | static void __perf_event_read(void *info) |
0793a61d | 4153 | { |
0492d4c5 PZ |
4154 | struct perf_read_data *data = info; |
4155 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4156 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4157 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4158 | struct pmu *pmu = event->pmu; |
621a01ea | 4159 | |
e1ac3614 PM |
4160 | /* |
4161 | * If this is a task context, we need to check whether it is | |
4162 | * the current task context of this cpu. If not it has been | |
4163 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4164 | * event->count would have been updated to a recent sample |
4165 | * when the event was scheduled out. | |
e1ac3614 PM |
4166 | */ |
4167 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4168 | return; | |
4169 | ||
e625cce1 | 4170 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4171 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4172 | update_context_time(ctx); |
e5d1367f SE |
4173 | update_cgrp_time_from_event(event); |
4174 | } | |
0492d4c5 | 4175 | |
0d3d73aa PZ |
4176 | perf_event_update_time(event); |
4177 | if (data->group) | |
4178 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4179 | |
4a00c16e SB |
4180 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4181 | goto unlock; | |
0492d4c5 | 4182 | |
4a00c16e SB |
4183 | if (!data->group) { |
4184 | pmu->read(event); | |
4185 | data->ret = 0; | |
0492d4c5 | 4186 | goto unlock; |
4a00c16e SB |
4187 | } |
4188 | ||
4189 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4190 | ||
4191 | pmu->read(event); | |
0492d4c5 | 4192 | |
edb39592 | 4193 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4194 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4195 | /* | |
4196 | * Use sibling's PMU rather than @event's since | |
4197 | * sibling could be on different (eg: software) PMU. | |
4198 | */ | |
0492d4c5 | 4199 | sub->pmu->read(sub); |
4a00c16e | 4200 | } |
0492d4c5 | 4201 | } |
4a00c16e SB |
4202 | |
4203 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4204 | |
4205 | unlock: | |
e625cce1 | 4206 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4207 | } |
4208 | ||
b5e58793 PZ |
4209 | static inline u64 perf_event_count(struct perf_event *event) |
4210 | { | |
c39a0e2c | 4211 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4212 | } |
4213 | ||
ffe8690c KX |
4214 | /* |
4215 | * NMI-safe method to read a local event, that is an event that | |
4216 | * is: | |
4217 | * - either for the current task, or for this CPU | |
4218 | * - does not have inherit set, for inherited task events | |
4219 | * will not be local and we cannot read them atomically | |
4220 | * - must not have a pmu::count method | |
4221 | */ | |
7d9285e8 YS |
4222 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4223 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4224 | { |
4225 | unsigned long flags; | |
f91840a3 | 4226 | int ret = 0; |
ffe8690c KX |
4227 | |
4228 | /* | |
4229 | * Disabling interrupts avoids all counter scheduling (context | |
4230 | * switches, timer based rotation and IPIs). | |
4231 | */ | |
4232 | local_irq_save(flags); | |
4233 | ||
ffe8690c KX |
4234 | /* |
4235 | * It must not be an event with inherit set, we cannot read | |
4236 | * all child counters from atomic context. | |
4237 | */ | |
f91840a3 AS |
4238 | if (event->attr.inherit) { |
4239 | ret = -EOPNOTSUPP; | |
4240 | goto out; | |
4241 | } | |
ffe8690c | 4242 | |
f91840a3 AS |
4243 | /* If this is a per-task event, it must be for current */ |
4244 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4245 | event->hw.target != current) { | |
4246 | ret = -EINVAL; | |
4247 | goto out; | |
4248 | } | |
4249 | ||
4250 | /* If this is a per-CPU event, it must be for this CPU */ | |
4251 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4252 | event->cpu != smp_processor_id()) { | |
4253 | ret = -EINVAL; | |
4254 | goto out; | |
4255 | } | |
ffe8690c | 4256 | |
befb1b3c RC |
4257 | /* If this is a pinned event it must be running on this CPU */ |
4258 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4259 | ret = -EBUSY; | |
4260 | goto out; | |
4261 | } | |
4262 | ||
ffe8690c KX |
4263 | /* |
4264 | * If the event is currently on this CPU, its either a per-task event, | |
4265 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4266 | * oncpu == -1). | |
4267 | */ | |
4268 | if (event->oncpu == smp_processor_id()) | |
4269 | event->pmu->read(event); | |
4270 | ||
f91840a3 | 4271 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4272 | if (enabled || running) { |
4273 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4274 | u64 __enabled, __running; | |
4275 | ||
4276 | __perf_update_times(event, now, &__enabled, &__running); | |
4277 | if (enabled) | |
4278 | *enabled = __enabled; | |
4279 | if (running) | |
4280 | *running = __running; | |
4281 | } | |
f91840a3 | 4282 | out: |
ffe8690c KX |
4283 | local_irq_restore(flags); |
4284 | ||
f91840a3 | 4285 | return ret; |
ffe8690c KX |
4286 | } |
4287 | ||
7d88962e | 4288 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4289 | { |
0c1cbc18 | 4290 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4291 | int event_cpu, ret = 0; |
7d88962e | 4292 | |
0793a61d | 4293 | /* |
cdd6c482 IM |
4294 | * If event is enabled and currently active on a CPU, update the |
4295 | * value in the event structure: | |
0793a61d | 4296 | */ |
0c1cbc18 PZ |
4297 | again: |
4298 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4299 | struct perf_read_data data; | |
4300 | ||
4301 | /* | |
4302 | * Orders the ->state and ->oncpu loads such that if we see | |
4303 | * ACTIVE we must also see the right ->oncpu. | |
4304 | * | |
4305 | * Matches the smp_wmb() from event_sched_in(). | |
4306 | */ | |
4307 | smp_rmb(); | |
d6a2f903 | 4308 | |
451d24d1 PZ |
4309 | event_cpu = READ_ONCE(event->oncpu); |
4310 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4311 | return 0; | |
4312 | ||
0c1cbc18 PZ |
4313 | data = (struct perf_read_data){ |
4314 | .event = event, | |
4315 | .group = group, | |
4316 | .ret = 0, | |
4317 | }; | |
4318 | ||
451d24d1 PZ |
4319 | preempt_disable(); |
4320 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4321 | |
58763148 PZ |
4322 | /* |
4323 | * Purposely ignore the smp_call_function_single() return | |
4324 | * value. | |
4325 | * | |
451d24d1 | 4326 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4327 | * scheduled out and that will have updated the event count. |
4328 | * | |
4329 | * Therefore, either way, we'll have an up-to-date event count | |
4330 | * after this. | |
4331 | */ | |
451d24d1 PZ |
4332 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4333 | preempt_enable(); | |
58763148 | 4334 | ret = data.ret; |
0c1cbc18 PZ |
4335 | |
4336 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4337 | struct perf_event_context *ctx = event->ctx; |
4338 | unsigned long flags; | |
4339 | ||
e625cce1 | 4340 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4341 | state = event->state; |
4342 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4343 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4344 | goto again; | |
4345 | } | |
4346 | ||
c530ccd9 | 4347 | /* |
0c1cbc18 PZ |
4348 | * May read while context is not active (e.g., thread is |
4349 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4350 | */ |
0c1cbc18 | 4351 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4352 | update_context_time(ctx); |
e5d1367f SE |
4353 | update_cgrp_time_from_event(event); |
4354 | } | |
0c1cbc18 | 4355 | |
0d3d73aa | 4356 | perf_event_update_time(event); |
0492d4c5 | 4357 | if (group) |
0d3d73aa | 4358 | perf_event_update_sibling_time(event); |
e625cce1 | 4359 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4360 | } |
7d88962e SB |
4361 | |
4362 | return ret; | |
0793a61d TG |
4363 | } |
4364 | ||
a63eaf34 | 4365 | /* |
cdd6c482 | 4366 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4367 | */ |
eb184479 | 4368 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4369 | { |
e625cce1 | 4370 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4371 | mutex_init(&ctx->mutex); |
2fde4f94 | 4372 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4373 | perf_event_groups_init(&ctx->pinned_groups); |
4374 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4375 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4376 | INIT_LIST_HEAD(&ctx->pinned_active); |
4377 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4378 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4379 | } |
4380 | ||
4381 | static struct perf_event_context * | |
4382 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4383 | { | |
4384 | struct perf_event_context *ctx; | |
4385 | ||
4386 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4387 | if (!ctx) | |
4388 | return NULL; | |
4389 | ||
4390 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4391 | if (task) |
4392 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4393 | ctx->pmu = pmu; |
4394 | ||
4395 | return ctx; | |
a63eaf34 PM |
4396 | } |
4397 | ||
2ebd4ffb MH |
4398 | static struct task_struct * |
4399 | find_lively_task_by_vpid(pid_t vpid) | |
4400 | { | |
4401 | struct task_struct *task; | |
0793a61d TG |
4402 | |
4403 | rcu_read_lock(); | |
2ebd4ffb | 4404 | if (!vpid) |
0793a61d TG |
4405 | task = current; |
4406 | else | |
2ebd4ffb | 4407 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4408 | if (task) |
4409 | get_task_struct(task); | |
4410 | rcu_read_unlock(); | |
4411 | ||
4412 | if (!task) | |
4413 | return ERR_PTR(-ESRCH); | |
4414 | ||
2ebd4ffb | 4415 | return task; |
2ebd4ffb MH |
4416 | } |
4417 | ||
fe4b04fa PZ |
4418 | /* |
4419 | * Returns a matching context with refcount and pincount. | |
4420 | */ | |
108b02cf | 4421 | static struct perf_event_context * |
4af57ef2 YZ |
4422 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4423 | struct perf_event *event) | |
0793a61d | 4424 | { |
211de6eb | 4425 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4426 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4427 | void *task_ctx_data = NULL; |
25346b93 | 4428 | unsigned long flags; |
8dc85d54 | 4429 | int ctxn, err; |
4af57ef2 | 4430 | int cpu = event->cpu; |
0793a61d | 4431 | |
22a4ec72 | 4432 | if (!task) { |
cdd6c482 | 4433 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4434 | err = perf_allow_cpu(&event->attr); |
4435 | if (err) | |
4436 | return ERR_PTR(err); | |
0793a61d | 4437 | |
108b02cf | 4438 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4439 | ctx = &cpuctx->ctx; |
c93f7669 | 4440 | get_ctx(ctx); |
fe4b04fa | 4441 | ++ctx->pin_count; |
0793a61d | 4442 | |
0793a61d TG |
4443 | return ctx; |
4444 | } | |
4445 | ||
8dc85d54 PZ |
4446 | err = -EINVAL; |
4447 | ctxn = pmu->task_ctx_nr; | |
4448 | if (ctxn < 0) | |
4449 | goto errout; | |
4450 | ||
4af57ef2 YZ |
4451 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4452 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4453 | if (!task_ctx_data) { | |
4454 | err = -ENOMEM; | |
4455 | goto errout; | |
4456 | } | |
4457 | } | |
4458 | ||
9ed6060d | 4459 | retry: |
8dc85d54 | 4460 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4461 | if (ctx) { |
211de6eb | 4462 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4463 | ++ctx->pin_count; |
4af57ef2 YZ |
4464 | |
4465 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4466 | ctx->task_ctx_data = task_ctx_data; | |
4467 | task_ctx_data = NULL; | |
4468 | } | |
e625cce1 | 4469 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4470 | |
4471 | if (clone_ctx) | |
4472 | put_ctx(clone_ctx); | |
9137fb28 | 4473 | } else { |
eb184479 | 4474 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4475 | err = -ENOMEM; |
4476 | if (!ctx) | |
4477 | goto errout; | |
eb184479 | 4478 | |
4af57ef2 YZ |
4479 | if (task_ctx_data) { |
4480 | ctx->task_ctx_data = task_ctx_data; | |
4481 | task_ctx_data = NULL; | |
4482 | } | |
4483 | ||
dbe08d82 ON |
4484 | err = 0; |
4485 | mutex_lock(&task->perf_event_mutex); | |
4486 | /* | |
4487 | * If it has already passed perf_event_exit_task(). | |
4488 | * we must see PF_EXITING, it takes this mutex too. | |
4489 | */ | |
4490 | if (task->flags & PF_EXITING) | |
4491 | err = -ESRCH; | |
4492 | else if (task->perf_event_ctxp[ctxn]) | |
4493 | err = -EAGAIN; | |
fe4b04fa | 4494 | else { |
9137fb28 | 4495 | get_ctx(ctx); |
fe4b04fa | 4496 | ++ctx->pin_count; |
dbe08d82 | 4497 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4498 | } |
dbe08d82 ON |
4499 | mutex_unlock(&task->perf_event_mutex); |
4500 | ||
4501 | if (unlikely(err)) { | |
9137fb28 | 4502 | put_ctx(ctx); |
dbe08d82 ON |
4503 | |
4504 | if (err == -EAGAIN) | |
4505 | goto retry; | |
4506 | goto errout; | |
a63eaf34 PM |
4507 | } |
4508 | } | |
4509 | ||
4af57ef2 | 4510 | kfree(task_ctx_data); |
0793a61d | 4511 | return ctx; |
c93f7669 | 4512 | |
9ed6060d | 4513 | errout: |
4af57ef2 | 4514 | kfree(task_ctx_data); |
c93f7669 | 4515 | return ERR_PTR(err); |
0793a61d TG |
4516 | } |
4517 | ||
6fb2915d | 4518 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4519 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4520 | |
cdd6c482 | 4521 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4522 | { |
cdd6c482 | 4523 | struct perf_event *event; |
592903cd | 4524 | |
cdd6c482 IM |
4525 | event = container_of(head, struct perf_event, rcu_head); |
4526 | if (event->ns) | |
4527 | put_pid_ns(event->ns); | |
6fb2915d | 4528 | perf_event_free_filter(event); |
cdd6c482 | 4529 | kfree(event); |
592903cd PZ |
4530 | } |
4531 | ||
b69cf536 | 4532 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4533 | struct perf_buffer *rb); |
925d519a | 4534 | |
f2fb6bef KL |
4535 | static void detach_sb_event(struct perf_event *event) |
4536 | { | |
4537 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4538 | ||
4539 | raw_spin_lock(&pel->lock); | |
4540 | list_del_rcu(&event->sb_list); | |
4541 | raw_spin_unlock(&pel->lock); | |
4542 | } | |
4543 | ||
a4f144eb | 4544 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4545 | { |
a4f144eb DCC |
4546 | struct perf_event_attr *attr = &event->attr; |
4547 | ||
f2fb6bef | 4548 | if (event->parent) |
a4f144eb | 4549 | return false; |
f2fb6bef KL |
4550 | |
4551 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4552 | return false; |
f2fb6bef | 4553 | |
a4f144eb DCC |
4554 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4555 | attr->comm || attr->comm_exec || | |
76193a94 | 4556 | attr->task || attr->ksymbol || |
21038f2b SL |
4557 | attr->context_switch || |
4558 | attr->bpf_event) | |
a4f144eb DCC |
4559 | return true; |
4560 | return false; | |
4561 | } | |
4562 | ||
4563 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4564 | { | |
4565 | if (is_sb_event(event)) | |
4566 | detach_sb_event(event); | |
f2fb6bef KL |
4567 | } |
4568 | ||
4beb31f3 | 4569 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4570 | { |
4beb31f3 FW |
4571 | if (event->parent) |
4572 | return; | |
4573 | ||
4beb31f3 FW |
4574 | if (is_cgroup_event(event)) |
4575 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4576 | } | |
925d519a | 4577 | |
555e0c1e FW |
4578 | #ifdef CONFIG_NO_HZ_FULL |
4579 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4580 | #endif | |
4581 | ||
4582 | static void unaccount_freq_event_nohz(void) | |
4583 | { | |
4584 | #ifdef CONFIG_NO_HZ_FULL | |
4585 | spin_lock(&nr_freq_lock); | |
4586 | if (atomic_dec_and_test(&nr_freq_events)) | |
4587 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4588 | spin_unlock(&nr_freq_lock); | |
4589 | #endif | |
4590 | } | |
4591 | ||
4592 | static void unaccount_freq_event(void) | |
4593 | { | |
4594 | if (tick_nohz_full_enabled()) | |
4595 | unaccount_freq_event_nohz(); | |
4596 | else | |
4597 | atomic_dec(&nr_freq_events); | |
4598 | } | |
4599 | ||
4beb31f3 FW |
4600 | static void unaccount_event(struct perf_event *event) |
4601 | { | |
25432ae9 PZ |
4602 | bool dec = false; |
4603 | ||
4beb31f3 FW |
4604 | if (event->parent) |
4605 | return; | |
4606 | ||
4607 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4608 | dec = true; |
4beb31f3 FW |
4609 | if (event->attr.mmap || event->attr.mmap_data) |
4610 | atomic_dec(&nr_mmap_events); | |
4611 | if (event->attr.comm) | |
4612 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4613 | if (event->attr.namespaces) |
4614 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4615 | if (event->attr.cgroup) |
4616 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4617 | if (event->attr.task) |
4618 | atomic_dec(&nr_task_events); | |
948b26b6 | 4619 | if (event->attr.freq) |
555e0c1e | 4620 | unaccount_freq_event(); |
45ac1403 | 4621 | if (event->attr.context_switch) { |
25432ae9 | 4622 | dec = true; |
45ac1403 AH |
4623 | atomic_dec(&nr_switch_events); |
4624 | } | |
4beb31f3 | 4625 | if (is_cgroup_event(event)) |
25432ae9 | 4626 | dec = true; |
4beb31f3 | 4627 | if (has_branch_stack(event)) |
25432ae9 | 4628 | dec = true; |
76193a94 SL |
4629 | if (event->attr.ksymbol) |
4630 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4631 | if (event->attr.bpf_event) |
4632 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4633 | |
9107c89e PZ |
4634 | if (dec) { |
4635 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4636 | schedule_delayed_work(&perf_sched_work, HZ); | |
4637 | } | |
4beb31f3 FW |
4638 | |
4639 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4640 | |
4641 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4642 | } |
925d519a | 4643 | |
9107c89e PZ |
4644 | static void perf_sched_delayed(struct work_struct *work) |
4645 | { | |
4646 | mutex_lock(&perf_sched_mutex); | |
4647 | if (atomic_dec_and_test(&perf_sched_count)) | |
4648 | static_branch_disable(&perf_sched_events); | |
4649 | mutex_unlock(&perf_sched_mutex); | |
4650 | } | |
4651 | ||
bed5b25a AS |
4652 | /* |
4653 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4654 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4655 | * at a time, so we disallow creating events that might conflict, namely: | |
4656 | * | |
4657 | * 1) cpu-wide events in the presence of per-task events, | |
4658 | * 2) per-task events in the presence of cpu-wide events, | |
4659 | * 3) two matching events on the same context. | |
4660 | * | |
4661 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4662 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4663 | */ |
4664 | static int exclusive_event_init(struct perf_event *event) | |
4665 | { | |
4666 | struct pmu *pmu = event->pmu; | |
4667 | ||
8a58ddae | 4668 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4669 | return 0; |
4670 | ||
4671 | /* | |
4672 | * Prevent co-existence of per-task and cpu-wide events on the | |
4673 | * same exclusive pmu. | |
4674 | * | |
4675 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4676 | * events on this "exclusive" pmu, positive means there are | |
4677 | * per-task events. | |
4678 | * | |
4679 | * Since this is called in perf_event_alloc() path, event::ctx | |
4680 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4681 | * to mean "per-task event", because unlike other attach states it | |
4682 | * never gets cleared. | |
4683 | */ | |
4684 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4685 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4686 | return -EBUSY; | |
4687 | } else { | |
4688 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4689 | return -EBUSY; | |
4690 | } | |
4691 | ||
4692 | return 0; | |
4693 | } | |
4694 | ||
4695 | static void exclusive_event_destroy(struct perf_event *event) | |
4696 | { | |
4697 | struct pmu *pmu = event->pmu; | |
4698 | ||
8a58ddae | 4699 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4700 | return; |
4701 | ||
4702 | /* see comment in exclusive_event_init() */ | |
4703 | if (event->attach_state & PERF_ATTACH_TASK) | |
4704 | atomic_dec(&pmu->exclusive_cnt); | |
4705 | else | |
4706 | atomic_inc(&pmu->exclusive_cnt); | |
4707 | } | |
4708 | ||
4709 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4710 | { | |
3bf6215a | 4711 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4712 | (e1->cpu == e2->cpu || |
4713 | e1->cpu == -1 || | |
4714 | e2->cpu == -1)) | |
4715 | return true; | |
4716 | return false; | |
4717 | } | |
4718 | ||
bed5b25a AS |
4719 | static bool exclusive_event_installable(struct perf_event *event, |
4720 | struct perf_event_context *ctx) | |
4721 | { | |
4722 | struct perf_event *iter_event; | |
4723 | struct pmu *pmu = event->pmu; | |
4724 | ||
8a58ddae AS |
4725 | lockdep_assert_held(&ctx->mutex); |
4726 | ||
4727 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4728 | return true; |
4729 | ||
4730 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4731 | if (exclusive_event_match(iter_event, event)) | |
4732 | return false; | |
4733 | } | |
4734 | ||
4735 | return true; | |
4736 | } | |
4737 | ||
375637bc AS |
4738 | static void perf_addr_filters_splice(struct perf_event *event, |
4739 | struct list_head *head); | |
4740 | ||
683ede43 | 4741 | static void _free_event(struct perf_event *event) |
f1600952 | 4742 | { |
e360adbe | 4743 | irq_work_sync(&event->pending); |
925d519a | 4744 | |
4beb31f3 | 4745 | unaccount_event(event); |
9ee318a7 | 4746 | |
da97e184 JFG |
4747 | security_perf_event_free(event); |
4748 | ||
76369139 | 4749 | if (event->rb) { |
9bb5d40c PZ |
4750 | /* |
4751 | * Can happen when we close an event with re-directed output. | |
4752 | * | |
4753 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4754 | * over us; possibly making our ring_buffer_put() the last. | |
4755 | */ | |
4756 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4757 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4758 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4759 | } |
4760 | ||
e5d1367f SE |
4761 | if (is_cgroup_event(event)) |
4762 | perf_detach_cgroup(event); | |
4763 | ||
a0733e69 PZ |
4764 | if (!event->parent) { |
4765 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4766 | put_callchain_buffers(); | |
4767 | } | |
4768 | ||
4769 | perf_event_free_bpf_prog(event); | |
375637bc | 4770 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4771 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4772 | |
4773 | if (event->destroy) | |
4774 | event->destroy(event); | |
4775 | ||
1cf8dfe8 PZ |
4776 | /* |
4777 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4778 | * hw.target. | |
4779 | */ | |
621b6d2e PB |
4780 | if (event->hw.target) |
4781 | put_task_struct(event->hw.target); | |
4782 | ||
1cf8dfe8 PZ |
4783 | /* |
4784 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4785 | * all task references must be cleaned up. | |
4786 | */ | |
4787 | if (event->ctx) | |
4788 | put_ctx(event->ctx); | |
4789 | ||
62a92c8f AS |
4790 | exclusive_event_destroy(event); |
4791 | module_put(event->pmu->module); | |
a0733e69 PZ |
4792 | |
4793 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4794 | } |
4795 | ||
683ede43 PZ |
4796 | /* |
4797 | * Used to free events which have a known refcount of 1, such as in error paths | |
4798 | * where the event isn't exposed yet and inherited events. | |
4799 | */ | |
4800 | static void free_event(struct perf_event *event) | |
0793a61d | 4801 | { |
683ede43 PZ |
4802 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4803 | "unexpected event refcount: %ld; ptr=%p\n", | |
4804 | atomic_long_read(&event->refcount), event)) { | |
4805 | /* leak to avoid use-after-free */ | |
4806 | return; | |
4807 | } | |
0793a61d | 4808 | |
683ede43 | 4809 | _free_event(event); |
0793a61d TG |
4810 | } |
4811 | ||
a66a3052 | 4812 | /* |
f8697762 | 4813 | * Remove user event from the owner task. |
a66a3052 | 4814 | */ |
f8697762 | 4815 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4816 | { |
8882135b | 4817 | struct task_struct *owner; |
fb0459d7 | 4818 | |
8882135b | 4819 | rcu_read_lock(); |
8882135b | 4820 | /* |
f47c02c0 PZ |
4821 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4822 | * observe !owner it means the list deletion is complete and we can | |
4823 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4824 | * owner->perf_event_mutex. |
4825 | */ | |
506458ef | 4826 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4827 | if (owner) { |
4828 | /* | |
4829 | * Since delayed_put_task_struct() also drops the last | |
4830 | * task reference we can safely take a new reference | |
4831 | * while holding the rcu_read_lock(). | |
4832 | */ | |
4833 | get_task_struct(owner); | |
4834 | } | |
4835 | rcu_read_unlock(); | |
4836 | ||
4837 | if (owner) { | |
f63a8daa PZ |
4838 | /* |
4839 | * If we're here through perf_event_exit_task() we're already | |
4840 | * holding ctx->mutex which would be an inversion wrt. the | |
4841 | * normal lock order. | |
4842 | * | |
4843 | * However we can safely take this lock because its the child | |
4844 | * ctx->mutex. | |
4845 | */ | |
4846 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4847 | ||
8882135b PZ |
4848 | /* |
4849 | * We have to re-check the event->owner field, if it is cleared | |
4850 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4851 | * ensured they're done, and we can proceed with freeing the | |
4852 | * event. | |
4853 | */ | |
f47c02c0 | 4854 | if (event->owner) { |
8882135b | 4855 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4856 | smp_store_release(&event->owner, NULL); |
4857 | } | |
8882135b PZ |
4858 | mutex_unlock(&owner->perf_event_mutex); |
4859 | put_task_struct(owner); | |
4860 | } | |
f8697762 JO |
4861 | } |
4862 | ||
f8697762 JO |
4863 | static void put_event(struct perf_event *event) |
4864 | { | |
f8697762 JO |
4865 | if (!atomic_long_dec_and_test(&event->refcount)) |
4866 | return; | |
4867 | ||
c6e5b732 PZ |
4868 | _free_event(event); |
4869 | } | |
4870 | ||
4871 | /* | |
4872 | * Kill an event dead; while event:refcount will preserve the event | |
4873 | * object, it will not preserve its functionality. Once the last 'user' | |
4874 | * gives up the object, we'll destroy the thing. | |
4875 | */ | |
4876 | int perf_event_release_kernel(struct perf_event *event) | |
4877 | { | |
a4f4bb6d | 4878 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4879 | struct perf_event *child, *tmp; |
82d94856 | 4880 | LIST_HEAD(free_list); |
c6e5b732 | 4881 | |
a4f4bb6d PZ |
4882 | /* |
4883 | * If we got here through err_file: fput(event_file); we will not have | |
4884 | * attached to a context yet. | |
4885 | */ | |
4886 | if (!ctx) { | |
4887 | WARN_ON_ONCE(event->attach_state & | |
4888 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4889 | goto no_ctx; | |
4890 | } | |
4891 | ||
f8697762 JO |
4892 | if (!is_kernel_event(event)) |
4893 | perf_remove_from_owner(event); | |
8882135b | 4894 | |
5fa7c8ec | 4895 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4896 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4897 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4898 | |
a69b0ca4 | 4899 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4900 | /* |
d8a8cfc7 | 4901 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4902 | * anymore. |
683ede43 | 4903 | * |
a69b0ca4 PZ |
4904 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4905 | * also see this, most importantly inherit_event() which will avoid | |
4906 | * placing more children on the list. | |
683ede43 | 4907 | * |
c6e5b732 PZ |
4908 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4909 | * child events. | |
683ede43 | 4910 | */ |
a69b0ca4 PZ |
4911 | event->state = PERF_EVENT_STATE_DEAD; |
4912 | raw_spin_unlock_irq(&ctx->lock); | |
4913 | ||
4914 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4915 | |
c6e5b732 PZ |
4916 | again: |
4917 | mutex_lock(&event->child_mutex); | |
4918 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4919 | |
c6e5b732 PZ |
4920 | /* |
4921 | * Cannot change, child events are not migrated, see the | |
4922 | * comment with perf_event_ctx_lock_nested(). | |
4923 | */ | |
506458ef | 4924 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4925 | /* |
4926 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4927 | * through hoops. We start by grabbing a reference on the ctx. | |
4928 | * | |
4929 | * Since the event cannot get freed while we hold the | |
4930 | * child_mutex, the context must also exist and have a !0 | |
4931 | * reference count. | |
4932 | */ | |
4933 | get_ctx(ctx); | |
4934 | ||
4935 | /* | |
4936 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4937 | * acquire ctx::mutex without fear of it going away. Then we | |
4938 | * can re-acquire child_mutex. | |
4939 | */ | |
4940 | mutex_unlock(&event->child_mutex); | |
4941 | mutex_lock(&ctx->mutex); | |
4942 | mutex_lock(&event->child_mutex); | |
4943 | ||
4944 | /* | |
4945 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4946 | * state, if child is still the first entry, it didn't get freed | |
4947 | * and we can continue doing so. | |
4948 | */ | |
4949 | tmp = list_first_entry_or_null(&event->child_list, | |
4950 | struct perf_event, child_list); | |
4951 | if (tmp == child) { | |
4952 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4953 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4954 | /* |
4955 | * This matches the refcount bump in inherit_event(); | |
4956 | * this can't be the last reference. | |
4957 | */ | |
4958 | put_event(event); | |
4959 | } | |
4960 | ||
4961 | mutex_unlock(&event->child_mutex); | |
4962 | mutex_unlock(&ctx->mutex); | |
4963 | put_ctx(ctx); | |
4964 | goto again; | |
4965 | } | |
4966 | mutex_unlock(&event->child_mutex); | |
4967 | ||
82d94856 | 4968 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4969 | void *var = &child->ctx->refcount; |
4970 | ||
82d94856 PZ |
4971 | list_del(&child->child_list); |
4972 | free_event(child); | |
1cf8dfe8 PZ |
4973 | |
4974 | /* | |
4975 | * Wake any perf_event_free_task() waiting for this event to be | |
4976 | * freed. | |
4977 | */ | |
4978 | smp_mb(); /* pairs with wait_var_event() */ | |
4979 | wake_up_var(var); | |
82d94856 PZ |
4980 | } |
4981 | ||
a4f4bb6d PZ |
4982 | no_ctx: |
4983 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4984 | return 0; |
4985 | } | |
4986 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4987 | ||
8b10c5e2 PZ |
4988 | /* |
4989 | * Called when the last reference to the file is gone. | |
4990 | */ | |
a6fa941d AV |
4991 | static int perf_release(struct inode *inode, struct file *file) |
4992 | { | |
c6e5b732 | 4993 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4994 | return 0; |
fb0459d7 | 4995 | } |
fb0459d7 | 4996 | |
ca0dd44c | 4997 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4998 | { |
cdd6c482 | 4999 | struct perf_event *child; |
e53c0994 PZ |
5000 | u64 total = 0; |
5001 | ||
59ed446f PZ |
5002 | *enabled = 0; |
5003 | *running = 0; | |
5004 | ||
6f10581a | 5005 | mutex_lock(&event->child_mutex); |
01add3ea | 5006 | |
7d88962e | 5007 | (void)perf_event_read(event, false); |
01add3ea SB |
5008 | total += perf_event_count(event); |
5009 | ||
59ed446f PZ |
5010 | *enabled += event->total_time_enabled + |
5011 | atomic64_read(&event->child_total_time_enabled); | |
5012 | *running += event->total_time_running + | |
5013 | atomic64_read(&event->child_total_time_running); | |
5014 | ||
5015 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5016 | (void)perf_event_read(child, false); |
01add3ea | 5017 | total += perf_event_count(child); |
59ed446f PZ |
5018 | *enabled += child->total_time_enabled; |
5019 | *running += child->total_time_running; | |
5020 | } | |
6f10581a | 5021 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5022 | |
5023 | return total; | |
5024 | } | |
ca0dd44c PZ |
5025 | |
5026 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5027 | { | |
5028 | struct perf_event_context *ctx; | |
5029 | u64 count; | |
5030 | ||
5031 | ctx = perf_event_ctx_lock(event); | |
5032 | count = __perf_event_read_value(event, enabled, running); | |
5033 | perf_event_ctx_unlock(event, ctx); | |
5034 | ||
5035 | return count; | |
5036 | } | |
fb0459d7 | 5037 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5038 | |
7d88962e | 5039 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5040 | u64 read_format, u64 *values) |
3dab77fb | 5041 | { |
2aeb1883 | 5042 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5043 | struct perf_event *sub; |
2aeb1883 | 5044 | unsigned long flags; |
fa8c2693 | 5045 | int n = 1; /* skip @nr */ |
7d88962e | 5046 | int ret; |
f63a8daa | 5047 | |
7d88962e SB |
5048 | ret = perf_event_read(leader, true); |
5049 | if (ret) | |
5050 | return ret; | |
abf4868b | 5051 | |
a9cd8194 PZ |
5052 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5053 | ||
fa8c2693 PZ |
5054 | /* |
5055 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5056 | * will be identical to those of the leader, so we only publish one | |
5057 | * set. | |
5058 | */ | |
5059 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5060 | values[n++] += leader->total_time_enabled + | |
5061 | atomic64_read(&leader->child_total_time_enabled); | |
5062 | } | |
3dab77fb | 5063 | |
fa8c2693 PZ |
5064 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5065 | values[n++] += leader->total_time_running + | |
5066 | atomic64_read(&leader->child_total_time_running); | |
5067 | } | |
5068 | ||
5069 | /* | |
5070 | * Write {count,id} tuples for every sibling. | |
5071 | */ | |
5072 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5073 | if (read_format & PERF_FORMAT_ID) |
5074 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5075 | |
edb39592 | 5076 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5077 | values[n++] += perf_event_count(sub); |
5078 | if (read_format & PERF_FORMAT_ID) | |
5079 | values[n++] = primary_event_id(sub); | |
5080 | } | |
7d88962e | 5081 | |
2aeb1883 | 5082 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5083 | return 0; |
fa8c2693 | 5084 | } |
3dab77fb | 5085 | |
fa8c2693 PZ |
5086 | static int perf_read_group(struct perf_event *event, |
5087 | u64 read_format, char __user *buf) | |
5088 | { | |
5089 | struct perf_event *leader = event->group_leader, *child; | |
5090 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5091 | int ret; |
fa8c2693 | 5092 | u64 *values; |
3dab77fb | 5093 | |
fa8c2693 | 5094 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5095 | |
fa8c2693 PZ |
5096 | values = kzalloc(event->read_size, GFP_KERNEL); |
5097 | if (!values) | |
5098 | return -ENOMEM; | |
3dab77fb | 5099 | |
fa8c2693 PZ |
5100 | values[0] = 1 + leader->nr_siblings; |
5101 | ||
5102 | /* | |
5103 | * By locking the child_mutex of the leader we effectively | |
5104 | * lock the child list of all siblings.. XXX explain how. | |
5105 | */ | |
5106 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5107 | |
7d88962e SB |
5108 | ret = __perf_read_group_add(leader, read_format, values); |
5109 | if (ret) | |
5110 | goto unlock; | |
5111 | ||
5112 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5113 | ret = __perf_read_group_add(child, read_format, values); | |
5114 | if (ret) | |
5115 | goto unlock; | |
5116 | } | |
abf4868b | 5117 | |
fa8c2693 | 5118 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5119 | |
7d88962e | 5120 | ret = event->read_size; |
fa8c2693 PZ |
5121 | if (copy_to_user(buf, values, event->read_size)) |
5122 | ret = -EFAULT; | |
7d88962e | 5123 | goto out; |
fa8c2693 | 5124 | |
7d88962e SB |
5125 | unlock: |
5126 | mutex_unlock(&leader->child_mutex); | |
5127 | out: | |
fa8c2693 | 5128 | kfree(values); |
abf4868b | 5129 | return ret; |
3dab77fb PZ |
5130 | } |
5131 | ||
b15f495b | 5132 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5133 | u64 read_format, char __user *buf) |
5134 | { | |
59ed446f | 5135 | u64 enabled, running; |
3dab77fb PZ |
5136 | u64 values[4]; |
5137 | int n = 0; | |
5138 | ||
ca0dd44c | 5139 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5140 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5141 | values[n++] = enabled; | |
5142 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5143 | values[n++] = running; | |
3dab77fb | 5144 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5145 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5146 | |
5147 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5148 | return -EFAULT; | |
5149 | ||
5150 | return n * sizeof(u64); | |
5151 | } | |
5152 | ||
dc633982 JO |
5153 | static bool is_event_hup(struct perf_event *event) |
5154 | { | |
5155 | bool no_children; | |
5156 | ||
a69b0ca4 | 5157 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5158 | return false; |
5159 | ||
5160 | mutex_lock(&event->child_mutex); | |
5161 | no_children = list_empty(&event->child_list); | |
5162 | mutex_unlock(&event->child_mutex); | |
5163 | return no_children; | |
5164 | } | |
5165 | ||
0793a61d | 5166 | /* |
cdd6c482 | 5167 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5168 | */ |
5169 | static ssize_t | |
b15f495b | 5170 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5171 | { |
cdd6c482 | 5172 | u64 read_format = event->attr.read_format; |
3dab77fb | 5173 | int ret; |
0793a61d | 5174 | |
3b6f9e5c | 5175 | /* |
788faab7 | 5176 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5177 | * error state (i.e. because it was pinned but it couldn't be |
5178 | * scheduled on to the CPU at some point). | |
5179 | */ | |
cdd6c482 | 5180 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5181 | return 0; |
5182 | ||
c320c7b7 | 5183 | if (count < event->read_size) |
3dab77fb PZ |
5184 | return -ENOSPC; |
5185 | ||
cdd6c482 | 5186 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5187 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5188 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5189 | else |
b15f495b | 5190 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5191 | |
3dab77fb | 5192 | return ret; |
0793a61d TG |
5193 | } |
5194 | ||
0793a61d TG |
5195 | static ssize_t |
5196 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5197 | { | |
cdd6c482 | 5198 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5199 | struct perf_event_context *ctx; |
5200 | int ret; | |
0793a61d | 5201 | |
da97e184 JFG |
5202 | ret = security_perf_event_read(event); |
5203 | if (ret) | |
5204 | return ret; | |
5205 | ||
f63a8daa | 5206 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5207 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5208 | perf_event_ctx_unlock(event, ctx); |
5209 | ||
5210 | return ret; | |
0793a61d TG |
5211 | } |
5212 | ||
9dd95748 | 5213 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5214 | { |
cdd6c482 | 5215 | struct perf_event *event = file->private_data; |
56de4e8f | 5216 | struct perf_buffer *rb; |
a9a08845 | 5217 | __poll_t events = EPOLLHUP; |
c7138f37 | 5218 | |
e708d7ad | 5219 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5220 | |
dc633982 | 5221 | if (is_event_hup(event)) |
179033b3 | 5222 | return events; |
c7138f37 | 5223 | |
10c6db11 | 5224 | /* |
9bb5d40c PZ |
5225 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5226 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5227 | */ |
5228 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5229 | rb = event->rb; |
5230 | if (rb) | |
76369139 | 5231 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5232 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5233 | return events; |
5234 | } | |
5235 | ||
f63a8daa | 5236 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5237 | { |
7d88962e | 5238 | (void)perf_event_read(event, false); |
e7850595 | 5239 | local64_set(&event->count, 0); |
cdd6c482 | 5240 | perf_event_update_userpage(event); |
3df5edad PZ |
5241 | } |
5242 | ||
52ba4b0b LX |
5243 | /* Assume it's not an event with inherit set. */ |
5244 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5245 | { | |
5246 | struct perf_event_context *ctx; | |
5247 | u64 count; | |
5248 | ||
5249 | ctx = perf_event_ctx_lock(event); | |
5250 | WARN_ON_ONCE(event->attr.inherit); | |
5251 | _perf_event_disable(event); | |
5252 | count = local64_read(&event->count); | |
5253 | if (reset) | |
5254 | local64_set(&event->count, 0); | |
5255 | perf_event_ctx_unlock(event, ctx); | |
5256 | ||
5257 | return count; | |
5258 | } | |
5259 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5260 | ||
c93f7669 | 5261 | /* |
cdd6c482 IM |
5262 | * Holding the top-level event's child_mutex means that any |
5263 | * descendant process that has inherited this event will block | |
8ba289b8 | 5264 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5265 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5266 | */ |
cdd6c482 IM |
5267 | static void perf_event_for_each_child(struct perf_event *event, |
5268 | void (*func)(struct perf_event *)) | |
3df5edad | 5269 | { |
cdd6c482 | 5270 | struct perf_event *child; |
3df5edad | 5271 | |
cdd6c482 | 5272 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5273 | |
cdd6c482 IM |
5274 | mutex_lock(&event->child_mutex); |
5275 | func(event); | |
5276 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5277 | func(child); |
cdd6c482 | 5278 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5279 | } |
5280 | ||
cdd6c482 IM |
5281 | static void perf_event_for_each(struct perf_event *event, |
5282 | void (*func)(struct perf_event *)) | |
3df5edad | 5283 | { |
cdd6c482 IM |
5284 | struct perf_event_context *ctx = event->ctx; |
5285 | struct perf_event *sibling; | |
3df5edad | 5286 | |
f63a8daa PZ |
5287 | lockdep_assert_held(&ctx->mutex); |
5288 | ||
cdd6c482 | 5289 | event = event->group_leader; |
75f937f2 | 5290 | |
cdd6c482 | 5291 | perf_event_for_each_child(event, func); |
edb39592 | 5292 | for_each_sibling_event(sibling, event) |
724b6daa | 5293 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5294 | } |
5295 | ||
fae3fde6 PZ |
5296 | static void __perf_event_period(struct perf_event *event, |
5297 | struct perf_cpu_context *cpuctx, | |
5298 | struct perf_event_context *ctx, | |
5299 | void *info) | |
c7999c6f | 5300 | { |
fae3fde6 | 5301 | u64 value = *((u64 *)info); |
c7999c6f | 5302 | bool active; |
08247e31 | 5303 | |
cdd6c482 | 5304 | if (event->attr.freq) { |
cdd6c482 | 5305 | event->attr.sample_freq = value; |
08247e31 | 5306 | } else { |
cdd6c482 IM |
5307 | event->attr.sample_period = value; |
5308 | event->hw.sample_period = value; | |
08247e31 | 5309 | } |
bad7192b PZ |
5310 | |
5311 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5312 | if (active) { | |
5313 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5314 | /* |
5315 | * We could be throttled; unthrottle now to avoid the tick | |
5316 | * trying to unthrottle while we already re-started the event. | |
5317 | */ | |
5318 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5319 | event->hw.interrupts = 0; | |
5320 | perf_log_throttle(event, 1); | |
5321 | } | |
bad7192b PZ |
5322 | event->pmu->stop(event, PERF_EF_UPDATE); |
5323 | } | |
5324 | ||
5325 | local64_set(&event->hw.period_left, 0); | |
5326 | ||
5327 | if (active) { | |
5328 | event->pmu->start(event, PERF_EF_RELOAD); | |
5329 | perf_pmu_enable(ctx->pmu); | |
5330 | } | |
c7999c6f PZ |
5331 | } |
5332 | ||
81ec3f3c JO |
5333 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5334 | { | |
5335 | return event->pmu->check_period(event, value); | |
5336 | } | |
5337 | ||
3ca270fc | 5338 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5339 | { |
c7999c6f PZ |
5340 | if (!is_sampling_event(event)) |
5341 | return -EINVAL; | |
5342 | ||
c7999c6f PZ |
5343 | if (!value) |
5344 | return -EINVAL; | |
5345 | ||
5346 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5347 | return -EINVAL; | |
5348 | ||
81ec3f3c JO |
5349 | if (perf_event_check_period(event, value)) |
5350 | return -EINVAL; | |
5351 | ||
913a90bc RB |
5352 | if (!event->attr.freq && (value & (1ULL << 63))) |
5353 | return -EINVAL; | |
5354 | ||
fae3fde6 | 5355 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5356 | |
c7999c6f | 5357 | return 0; |
08247e31 PZ |
5358 | } |
5359 | ||
3ca270fc LX |
5360 | int perf_event_period(struct perf_event *event, u64 value) |
5361 | { | |
5362 | struct perf_event_context *ctx; | |
5363 | int ret; | |
5364 | ||
5365 | ctx = perf_event_ctx_lock(event); | |
5366 | ret = _perf_event_period(event, value); | |
5367 | perf_event_ctx_unlock(event, ctx); | |
5368 | ||
5369 | return ret; | |
5370 | } | |
5371 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5372 | ||
ac9721f3 PZ |
5373 | static const struct file_operations perf_fops; |
5374 | ||
2903ff01 | 5375 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5376 | { |
2903ff01 AV |
5377 | struct fd f = fdget(fd); |
5378 | if (!f.file) | |
5379 | return -EBADF; | |
ac9721f3 | 5380 | |
2903ff01 AV |
5381 | if (f.file->f_op != &perf_fops) { |
5382 | fdput(f); | |
5383 | return -EBADF; | |
ac9721f3 | 5384 | } |
2903ff01 AV |
5385 | *p = f; |
5386 | return 0; | |
ac9721f3 PZ |
5387 | } |
5388 | ||
5389 | static int perf_event_set_output(struct perf_event *event, | |
5390 | struct perf_event *output_event); | |
6fb2915d | 5391 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5392 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5393 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5394 | struct perf_event_attr *attr); | |
a4be7c27 | 5395 | |
f63a8daa | 5396 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5397 | { |
cdd6c482 | 5398 | void (*func)(struct perf_event *); |
3df5edad | 5399 | u32 flags = arg; |
d859e29f PM |
5400 | |
5401 | switch (cmd) { | |
cdd6c482 | 5402 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5403 | func = _perf_event_enable; |
d859e29f | 5404 | break; |
cdd6c482 | 5405 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5406 | func = _perf_event_disable; |
79f14641 | 5407 | break; |
cdd6c482 | 5408 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5409 | func = _perf_event_reset; |
6de6a7b9 | 5410 | break; |
3df5edad | 5411 | |
cdd6c482 | 5412 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5413 | return _perf_event_refresh(event, arg); |
08247e31 | 5414 | |
cdd6c482 | 5415 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5416 | { |
5417 | u64 value; | |
08247e31 | 5418 | |
3ca270fc LX |
5419 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5420 | return -EFAULT; | |
08247e31 | 5421 | |
3ca270fc LX |
5422 | return _perf_event_period(event, value); |
5423 | } | |
cf4957f1 JO |
5424 | case PERF_EVENT_IOC_ID: |
5425 | { | |
5426 | u64 id = primary_event_id(event); | |
5427 | ||
5428 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5429 | return -EFAULT; | |
5430 | return 0; | |
5431 | } | |
5432 | ||
cdd6c482 | 5433 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5434 | { |
ac9721f3 | 5435 | int ret; |
ac9721f3 | 5436 | if (arg != -1) { |
2903ff01 AV |
5437 | struct perf_event *output_event; |
5438 | struct fd output; | |
5439 | ret = perf_fget_light(arg, &output); | |
5440 | if (ret) | |
5441 | return ret; | |
5442 | output_event = output.file->private_data; | |
5443 | ret = perf_event_set_output(event, output_event); | |
5444 | fdput(output); | |
5445 | } else { | |
5446 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5447 | } |
ac9721f3 PZ |
5448 | return ret; |
5449 | } | |
a4be7c27 | 5450 | |
6fb2915d LZ |
5451 | case PERF_EVENT_IOC_SET_FILTER: |
5452 | return perf_event_set_filter(event, (void __user *)arg); | |
5453 | ||
2541517c AS |
5454 | case PERF_EVENT_IOC_SET_BPF: |
5455 | return perf_event_set_bpf_prog(event, arg); | |
5456 | ||
86e7972f | 5457 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5458 | struct perf_buffer *rb; |
86e7972f WN |
5459 | |
5460 | rcu_read_lock(); | |
5461 | rb = rcu_dereference(event->rb); | |
5462 | if (!rb || !rb->nr_pages) { | |
5463 | rcu_read_unlock(); | |
5464 | return -EINVAL; | |
5465 | } | |
5466 | rb_toggle_paused(rb, !!arg); | |
5467 | rcu_read_unlock(); | |
5468 | return 0; | |
5469 | } | |
f371b304 YS |
5470 | |
5471 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5472 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5473 | |
5474 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5475 | struct perf_event_attr new_attr; | |
5476 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5477 | &new_attr); | |
5478 | ||
5479 | if (err) | |
5480 | return err; | |
5481 | ||
5482 | return perf_event_modify_attr(event, &new_attr); | |
5483 | } | |
d859e29f | 5484 | default: |
3df5edad | 5485 | return -ENOTTY; |
d859e29f | 5486 | } |
3df5edad PZ |
5487 | |
5488 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5489 | perf_event_for_each(event, func); |
3df5edad | 5490 | else |
cdd6c482 | 5491 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5492 | |
5493 | return 0; | |
d859e29f PM |
5494 | } |
5495 | ||
f63a8daa PZ |
5496 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5497 | { | |
5498 | struct perf_event *event = file->private_data; | |
5499 | struct perf_event_context *ctx; | |
5500 | long ret; | |
5501 | ||
da97e184 JFG |
5502 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5503 | ret = security_perf_event_write(event); | |
5504 | if (ret) | |
5505 | return ret; | |
5506 | ||
f63a8daa PZ |
5507 | ctx = perf_event_ctx_lock(event); |
5508 | ret = _perf_ioctl(event, cmd, arg); | |
5509 | perf_event_ctx_unlock(event, ctx); | |
5510 | ||
5511 | return ret; | |
5512 | } | |
5513 | ||
b3f20785 PM |
5514 | #ifdef CONFIG_COMPAT |
5515 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5516 | unsigned long arg) | |
5517 | { | |
5518 | switch (_IOC_NR(cmd)) { | |
5519 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5520 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5521 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5522 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5523 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5524 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5525 | cmd &= ~IOCSIZE_MASK; | |
5526 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5527 | } | |
5528 | break; | |
5529 | } | |
5530 | return perf_ioctl(file, cmd, arg); | |
5531 | } | |
5532 | #else | |
5533 | # define perf_compat_ioctl NULL | |
5534 | #endif | |
5535 | ||
cdd6c482 | 5536 | int perf_event_task_enable(void) |
771d7cde | 5537 | { |
f63a8daa | 5538 | struct perf_event_context *ctx; |
cdd6c482 | 5539 | struct perf_event *event; |
771d7cde | 5540 | |
cdd6c482 | 5541 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5542 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5543 | ctx = perf_event_ctx_lock(event); | |
5544 | perf_event_for_each_child(event, _perf_event_enable); | |
5545 | perf_event_ctx_unlock(event, ctx); | |
5546 | } | |
cdd6c482 | 5547 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5548 | |
5549 | return 0; | |
5550 | } | |
5551 | ||
cdd6c482 | 5552 | int perf_event_task_disable(void) |
771d7cde | 5553 | { |
f63a8daa | 5554 | struct perf_event_context *ctx; |
cdd6c482 | 5555 | struct perf_event *event; |
771d7cde | 5556 | |
cdd6c482 | 5557 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5558 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5559 | ctx = perf_event_ctx_lock(event); | |
5560 | perf_event_for_each_child(event, _perf_event_disable); | |
5561 | perf_event_ctx_unlock(event, ctx); | |
5562 | } | |
cdd6c482 | 5563 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5564 | |
5565 | return 0; | |
5566 | } | |
5567 | ||
cdd6c482 | 5568 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5569 | { |
a4eaf7f1 PZ |
5570 | if (event->hw.state & PERF_HES_STOPPED) |
5571 | return 0; | |
5572 | ||
cdd6c482 | 5573 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5574 | return 0; |
5575 | ||
35edc2a5 | 5576 | return event->pmu->event_idx(event); |
194002b2 PZ |
5577 | } |
5578 | ||
c4794295 | 5579 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5580 | u64 *now, |
7f310a5d EM |
5581 | u64 *enabled, |
5582 | u64 *running) | |
c4794295 | 5583 | { |
e3f3541c | 5584 | u64 ctx_time; |
c4794295 | 5585 | |
e3f3541c PZ |
5586 | *now = perf_clock(); |
5587 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5588 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5589 | } |
5590 | ||
fa731587 PZ |
5591 | static void perf_event_init_userpage(struct perf_event *event) |
5592 | { | |
5593 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5594 | struct perf_buffer *rb; |
fa731587 PZ |
5595 | |
5596 | rcu_read_lock(); | |
5597 | rb = rcu_dereference(event->rb); | |
5598 | if (!rb) | |
5599 | goto unlock; | |
5600 | ||
5601 | userpg = rb->user_page; | |
5602 | ||
5603 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5604 | userpg->cap_bit0_is_deprecated = 1; | |
5605 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5606 | userpg->data_offset = PAGE_SIZE; |
5607 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5608 | |
5609 | unlock: | |
5610 | rcu_read_unlock(); | |
5611 | } | |
5612 | ||
c1317ec2 AL |
5613 | void __weak arch_perf_update_userpage( |
5614 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5615 | { |
5616 | } | |
5617 | ||
38ff667b PZ |
5618 | /* |
5619 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5620 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5621 | * code calls this from NMI context. | |
5622 | */ | |
cdd6c482 | 5623 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5624 | { |
cdd6c482 | 5625 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5626 | struct perf_buffer *rb; |
e3f3541c | 5627 | u64 enabled, running, now; |
38ff667b PZ |
5628 | |
5629 | rcu_read_lock(); | |
5ec4c599 PZ |
5630 | rb = rcu_dereference(event->rb); |
5631 | if (!rb) | |
5632 | goto unlock; | |
5633 | ||
0d641208 EM |
5634 | /* |
5635 | * compute total_time_enabled, total_time_running | |
5636 | * based on snapshot values taken when the event | |
5637 | * was last scheduled in. | |
5638 | * | |
5639 | * we cannot simply called update_context_time() | |
5640 | * because of locking issue as we can be called in | |
5641 | * NMI context | |
5642 | */ | |
e3f3541c | 5643 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5644 | |
76369139 | 5645 | userpg = rb->user_page; |
7b732a75 | 5646 | /* |
9d2dcc8f MF |
5647 | * Disable preemption to guarantee consistent time stamps are stored to |
5648 | * the user page. | |
7b732a75 PZ |
5649 | */ |
5650 | preempt_disable(); | |
37d81828 | 5651 | ++userpg->lock; |
92f22a38 | 5652 | barrier(); |
cdd6c482 | 5653 | userpg->index = perf_event_index(event); |
b5e58793 | 5654 | userpg->offset = perf_event_count(event); |
365a4038 | 5655 | if (userpg->index) |
e7850595 | 5656 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5657 | |
0d641208 | 5658 | userpg->time_enabled = enabled + |
cdd6c482 | 5659 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5660 | |
0d641208 | 5661 | userpg->time_running = running + |
cdd6c482 | 5662 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5663 | |
c1317ec2 | 5664 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5665 | |
92f22a38 | 5666 | barrier(); |
37d81828 | 5667 | ++userpg->lock; |
7b732a75 | 5668 | preempt_enable(); |
38ff667b | 5669 | unlock: |
7b732a75 | 5670 | rcu_read_unlock(); |
37d81828 | 5671 | } |
82975c46 | 5672 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5673 | |
9e3ed2d7 | 5674 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5675 | { |
11bac800 | 5676 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5677 | struct perf_buffer *rb; |
9e3ed2d7 | 5678 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5679 | |
5680 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5681 | if (vmf->pgoff == 0) | |
5682 | ret = 0; | |
5683 | return ret; | |
5684 | } | |
5685 | ||
5686 | rcu_read_lock(); | |
76369139 FW |
5687 | rb = rcu_dereference(event->rb); |
5688 | if (!rb) | |
906010b2 PZ |
5689 | goto unlock; |
5690 | ||
5691 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5692 | goto unlock; | |
5693 | ||
76369139 | 5694 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5695 | if (!vmf->page) |
5696 | goto unlock; | |
5697 | ||
5698 | get_page(vmf->page); | |
11bac800 | 5699 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5700 | vmf->page->index = vmf->pgoff; |
5701 | ||
5702 | ret = 0; | |
5703 | unlock: | |
5704 | rcu_read_unlock(); | |
5705 | ||
5706 | return ret; | |
5707 | } | |
5708 | ||
10c6db11 | 5709 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5710 | struct perf_buffer *rb) |
10c6db11 | 5711 | { |
56de4e8f | 5712 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5713 | unsigned long flags; |
5714 | ||
b69cf536 PZ |
5715 | if (event->rb) { |
5716 | /* | |
5717 | * Should be impossible, we set this when removing | |
5718 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5719 | */ | |
5720 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5721 | |
b69cf536 | 5722 | old_rb = event->rb; |
b69cf536 PZ |
5723 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5724 | list_del_rcu(&event->rb_entry); | |
5725 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5726 | |
2f993cf0 ON |
5727 | event->rcu_batches = get_state_synchronize_rcu(); |
5728 | event->rcu_pending = 1; | |
b69cf536 | 5729 | } |
10c6db11 | 5730 | |
b69cf536 | 5731 | if (rb) { |
2f993cf0 ON |
5732 | if (event->rcu_pending) { |
5733 | cond_synchronize_rcu(event->rcu_batches); | |
5734 | event->rcu_pending = 0; | |
5735 | } | |
5736 | ||
b69cf536 PZ |
5737 | spin_lock_irqsave(&rb->event_lock, flags); |
5738 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5739 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5740 | } | |
5741 | ||
767ae086 AS |
5742 | /* |
5743 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5744 | * before swizzling the event::rb pointer; if it's getting | |
5745 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5746 | * restart. See the comment in __perf_pmu_output_stop(). | |
5747 | * | |
5748 | * Data will inevitably be lost when set_output is done in | |
5749 | * mid-air, but then again, whoever does it like this is | |
5750 | * not in for the data anyway. | |
5751 | */ | |
5752 | if (has_aux(event)) | |
5753 | perf_event_stop(event, 0); | |
5754 | ||
b69cf536 PZ |
5755 | rcu_assign_pointer(event->rb, rb); |
5756 | ||
5757 | if (old_rb) { | |
5758 | ring_buffer_put(old_rb); | |
5759 | /* | |
5760 | * Since we detached before setting the new rb, so that we | |
5761 | * could attach the new rb, we could have missed a wakeup. | |
5762 | * Provide it now. | |
5763 | */ | |
5764 | wake_up_all(&event->waitq); | |
5765 | } | |
10c6db11 PZ |
5766 | } |
5767 | ||
5768 | static void ring_buffer_wakeup(struct perf_event *event) | |
5769 | { | |
56de4e8f | 5770 | struct perf_buffer *rb; |
10c6db11 PZ |
5771 | |
5772 | rcu_read_lock(); | |
5773 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5774 | if (rb) { |
5775 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5776 | wake_up_all(&event->waitq); | |
5777 | } | |
10c6db11 PZ |
5778 | rcu_read_unlock(); |
5779 | } | |
5780 | ||
56de4e8f | 5781 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5782 | { |
56de4e8f | 5783 | struct perf_buffer *rb; |
7b732a75 | 5784 | |
ac9721f3 | 5785 | rcu_read_lock(); |
76369139 FW |
5786 | rb = rcu_dereference(event->rb); |
5787 | if (rb) { | |
fecb8ed2 | 5788 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5789 | rb = NULL; |
ac9721f3 PZ |
5790 | } |
5791 | rcu_read_unlock(); | |
5792 | ||
76369139 | 5793 | return rb; |
ac9721f3 PZ |
5794 | } |
5795 | ||
56de4e8f | 5796 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5797 | { |
fecb8ed2 | 5798 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5799 | return; |
7b732a75 | 5800 | |
9bb5d40c | 5801 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5802 | |
76369139 | 5803 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5804 | } |
5805 | ||
5806 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5807 | { | |
cdd6c482 | 5808 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5809 | |
cdd6c482 | 5810 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5811 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5812 | |
45bfb2e5 PZ |
5813 | if (vma->vm_pgoff) |
5814 | atomic_inc(&event->rb->aux_mmap_count); | |
5815 | ||
1e0fb9ec | 5816 | if (event->pmu->event_mapped) |
bfe33492 | 5817 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5818 | } |
5819 | ||
95ff4ca2 AS |
5820 | static void perf_pmu_output_stop(struct perf_event *event); |
5821 | ||
9bb5d40c PZ |
5822 | /* |
5823 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5824 | * event, or through other events by use of perf_event_set_output(). | |
5825 | * | |
5826 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5827 | * the buffer here, where we still have a VM context. This means we need | |
5828 | * to detach all events redirecting to us. | |
5829 | */ | |
7b732a75 PZ |
5830 | static void perf_mmap_close(struct vm_area_struct *vma) |
5831 | { | |
cdd6c482 | 5832 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5833 | |
56de4e8f | 5834 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5835 | struct user_struct *mmap_user = rb->mmap_user; |
5836 | int mmap_locked = rb->mmap_locked; | |
5837 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5838 | |
1e0fb9ec | 5839 | if (event->pmu->event_unmapped) |
bfe33492 | 5840 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5841 | |
45bfb2e5 PZ |
5842 | /* |
5843 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5844 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5845 | * serialize with perf_mmap here. | |
5846 | */ | |
5847 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5848 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5849 | /* |
5850 | * Stop all AUX events that are writing to this buffer, | |
5851 | * so that we can free its AUX pages and corresponding PMU | |
5852 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5853 | * they won't start any more (see perf_aux_output_begin()). | |
5854 | */ | |
5855 | perf_pmu_output_stop(event); | |
5856 | ||
5857 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5858 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5859 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5860 | |
95ff4ca2 | 5861 | /* this has to be the last one */ |
45bfb2e5 | 5862 | rb_free_aux(rb); |
ca3bb3d0 | 5863 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5864 | |
45bfb2e5 PZ |
5865 | mutex_unlock(&event->mmap_mutex); |
5866 | } | |
5867 | ||
9bb5d40c PZ |
5868 | atomic_dec(&rb->mmap_count); |
5869 | ||
5870 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5871 | goto out_put; |
9bb5d40c | 5872 | |
b69cf536 | 5873 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5874 | mutex_unlock(&event->mmap_mutex); |
5875 | ||
5876 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5877 | if (atomic_read(&rb->mmap_count)) |
5878 | goto out_put; | |
ac9721f3 | 5879 | |
9bb5d40c PZ |
5880 | /* |
5881 | * No other mmap()s, detach from all other events that might redirect | |
5882 | * into the now unreachable buffer. Somewhat complicated by the | |
5883 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5884 | */ | |
5885 | again: | |
5886 | rcu_read_lock(); | |
5887 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5888 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5889 | /* | |
5890 | * This event is en-route to free_event() which will | |
5891 | * detach it and remove it from the list. | |
5892 | */ | |
5893 | continue; | |
5894 | } | |
5895 | rcu_read_unlock(); | |
789f90fc | 5896 | |
9bb5d40c PZ |
5897 | mutex_lock(&event->mmap_mutex); |
5898 | /* | |
5899 | * Check we didn't race with perf_event_set_output() which can | |
5900 | * swizzle the rb from under us while we were waiting to | |
5901 | * acquire mmap_mutex. | |
5902 | * | |
5903 | * If we find a different rb; ignore this event, a next | |
5904 | * iteration will no longer find it on the list. We have to | |
5905 | * still restart the iteration to make sure we're not now | |
5906 | * iterating the wrong list. | |
5907 | */ | |
b69cf536 PZ |
5908 | if (event->rb == rb) |
5909 | ring_buffer_attach(event, NULL); | |
5910 | ||
cdd6c482 | 5911 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5912 | put_event(event); |
ac9721f3 | 5913 | |
9bb5d40c PZ |
5914 | /* |
5915 | * Restart the iteration; either we're on the wrong list or | |
5916 | * destroyed its integrity by doing a deletion. | |
5917 | */ | |
5918 | goto again; | |
7b732a75 | 5919 | } |
9bb5d40c PZ |
5920 | rcu_read_unlock(); |
5921 | ||
5922 | /* | |
5923 | * It could be there's still a few 0-ref events on the list; they'll | |
5924 | * get cleaned up by free_event() -- they'll also still have their | |
5925 | * ref on the rb and will free it whenever they are done with it. | |
5926 | * | |
5927 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5928 | * undo the VM accounting. | |
5929 | */ | |
5930 | ||
d44248a4 SL |
5931 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5932 | &mmap_user->locked_vm); | |
70f8a3ca | 5933 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5934 | free_uid(mmap_user); |
5935 | ||
b69cf536 | 5936 | out_put: |
9bb5d40c | 5937 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5938 | } |
5939 | ||
f0f37e2f | 5940 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5941 | .open = perf_mmap_open, |
fca0c116 | 5942 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5943 | .fault = perf_mmap_fault, |
5944 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5945 | }; |
5946 | ||
5947 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5948 | { | |
cdd6c482 | 5949 | struct perf_event *event = file->private_data; |
22a4f650 | 5950 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5951 | struct user_struct *user = current_user(); |
56de4e8f | 5952 | struct perf_buffer *rb = NULL; |
22a4f650 | 5953 | unsigned long locked, lock_limit; |
7b732a75 PZ |
5954 | unsigned long vma_size; |
5955 | unsigned long nr_pages; | |
45bfb2e5 | 5956 | long user_extra = 0, extra = 0; |
d57e34fd | 5957 | int ret = 0, flags = 0; |
37d81828 | 5958 | |
c7920614 PZ |
5959 | /* |
5960 | * Don't allow mmap() of inherited per-task counters. This would | |
5961 | * create a performance issue due to all children writing to the | |
76369139 | 5962 | * same rb. |
c7920614 PZ |
5963 | */ |
5964 | if (event->cpu == -1 && event->attr.inherit) | |
5965 | return -EINVAL; | |
5966 | ||
43a21ea8 | 5967 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5968 | return -EINVAL; |
7b732a75 | 5969 | |
da97e184 JFG |
5970 | ret = security_perf_event_read(event); |
5971 | if (ret) | |
5972 | return ret; | |
5973 | ||
7b732a75 | 5974 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
5975 | |
5976 | if (vma->vm_pgoff == 0) { | |
5977 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5978 | } else { | |
5979 | /* | |
5980 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5981 | * mapped, all subsequent mappings should have the same size | |
5982 | * and offset. Must be above the normal perf buffer. | |
5983 | */ | |
5984 | u64 aux_offset, aux_size; | |
5985 | ||
5986 | if (!event->rb) | |
5987 | return -EINVAL; | |
5988 | ||
5989 | nr_pages = vma_size / PAGE_SIZE; | |
5990 | ||
5991 | mutex_lock(&event->mmap_mutex); | |
5992 | ret = -EINVAL; | |
5993 | ||
5994 | rb = event->rb; | |
5995 | if (!rb) | |
5996 | goto aux_unlock; | |
5997 | ||
6aa7de05 MR |
5998 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5999 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6000 | |
6001 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6002 | goto aux_unlock; | |
6003 | ||
6004 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6005 | goto aux_unlock; | |
6006 | ||
6007 | /* already mapped with a different offset */ | |
6008 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6009 | goto aux_unlock; | |
6010 | ||
6011 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6012 | goto aux_unlock; | |
6013 | ||
6014 | /* already mapped with a different size */ | |
6015 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6016 | goto aux_unlock; | |
6017 | ||
6018 | if (!is_power_of_2(nr_pages)) | |
6019 | goto aux_unlock; | |
6020 | ||
6021 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6022 | goto aux_unlock; | |
6023 | ||
6024 | if (rb_has_aux(rb)) { | |
6025 | atomic_inc(&rb->aux_mmap_count); | |
6026 | ret = 0; | |
6027 | goto unlock; | |
6028 | } | |
6029 | ||
6030 | atomic_set(&rb->aux_mmap_count, 1); | |
6031 | user_extra = nr_pages; | |
6032 | ||
6033 | goto accounting; | |
6034 | } | |
7b732a75 | 6035 | |
7730d865 | 6036 | /* |
76369139 | 6037 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6038 | * can do bitmasks instead of modulo. |
6039 | */ | |
2ed11312 | 6040 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6041 | return -EINVAL; |
6042 | ||
7b732a75 | 6043 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6044 | return -EINVAL; |
6045 | ||
cdd6c482 | 6046 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6047 | again: |
cdd6c482 | 6048 | mutex_lock(&event->mmap_mutex); |
76369139 | 6049 | if (event->rb) { |
9bb5d40c | 6050 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6051 | ret = -EINVAL; |
9bb5d40c PZ |
6052 | goto unlock; |
6053 | } | |
6054 | ||
6055 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6056 | /* | |
6057 | * Raced against perf_mmap_close() through | |
6058 | * perf_event_set_output(). Try again, hope for better | |
6059 | * luck. | |
6060 | */ | |
6061 | mutex_unlock(&event->mmap_mutex); | |
6062 | goto again; | |
6063 | } | |
6064 | ||
ebb3c4c4 PZ |
6065 | goto unlock; |
6066 | } | |
6067 | ||
789f90fc | 6068 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6069 | |
6070 | accounting: | |
cdd6c482 | 6071 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6072 | |
6073 | /* | |
6074 | * Increase the limit linearly with more CPUs: | |
6075 | */ | |
6076 | user_lock_limit *= num_online_cpus(); | |
6077 | ||
00346155 SL |
6078 | user_locked = atomic_long_read(&user->locked_vm); |
6079 | ||
6080 | /* | |
6081 | * sysctl_perf_event_mlock may have changed, so that | |
6082 | * user->locked_vm > user_lock_limit | |
6083 | */ | |
6084 | if (user_locked > user_lock_limit) | |
6085 | user_locked = user_lock_limit; | |
6086 | user_locked += user_extra; | |
c5078f78 | 6087 | |
c4b75479 | 6088 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6089 | /* |
6090 | * charge locked_vm until it hits user_lock_limit; | |
6091 | * charge the rest from pinned_vm | |
6092 | */ | |
789f90fc | 6093 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6094 | user_extra -= extra; |
6095 | } | |
7b732a75 | 6096 | |
78d7d407 | 6097 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6098 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6099 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6100 | |
da97e184 | 6101 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6102 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6103 | ret = -EPERM; |
6104 | goto unlock; | |
6105 | } | |
7b732a75 | 6106 | |
45bfb2e5 | 6107 | WARN_ON(!rb && event->rb); |
906010b2 | 6108 | |
d57e34fd | 6109 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6110 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6111 | |
76369139 | 6112 | if (!rb) { |
45bfb2e5 PZ |
6113 | rb = rb_alloc(nr_pages, |
6114 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6115 | event->cpu, flags); | |
26cb63ad | 6116 | |
45bfb2e5 PZ |
6117 | if (!rb) { |
6118 | ret = -ENOMEM; | |
6119 | goto unlock; | |
6120 | } | |
43a21ea8 | 6121 | |
45bfb2e5 PZ |
6122 | atomic_set(&rb->mmap_count, 1); |
6123 | rb->mmap_user = get_current_user(); | |
6124 | rb->mmap_locked = extra; | |
26cb63ad | 6125 | |
45bfb2e5 | 6126 | ring_buffer_attach(event, rb); |
ac9721f3 | 6127 | |
45bfb2e5 PZ |
6128 | perf_event_init_userpage(event); |
6129 | perf_event_update_userpage(event); | |
6130 | } else { | |
1a594131 AS |
6131 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6132 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6133 | if (!ret) |
6134 | rb->aux_mmap_locked = extra; | |
6135 | } | |
9a0f05cb | 6136 | |
ebb3c4c4 | 6137 | unlock: |
45bfb2e5 PZ |
6138 | if (!ret) { |
6139 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6140 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6141 | |
ac9721f3 | 6142 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6143 | } else if (rb) { |
6144 | atomic_dec(&rb->mmap_count); | |
6145 | } | |
6146 | aux_unlock: | |
cdd6c482 | 6147 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6148 | |
9bb5d40c PZ |
6149 | /* |
6150 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6151 | * vma. | |
6152 | */ | |
26cb63ad | 6153 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6154 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6155 | |
1e0fb9ec | 6156 | if (event->pmu->event_mapped) |
bfe33492 | 6157 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6158 | |
7b732a75 | 6159 | return ret; |
37d81828 PM |
6160 | } |
6161 | ||
3c446b3d PZ |
6162 | static int perf_fasync(int fd, struct file *filp, int on) |
6163 | { | |
496ad9aa | 6164 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6165 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6166 | int retval; |
6167 | ||
5955102c | 6168 | inode_lock(inode); |
cdd6c482 | 6169 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6170 | inode_unlock(inode); |
3c446b3d PZ |
6171 | |
6172 | if (retval < 0) | |
6173 | return retval; | |
6174 | ||
6175 | return 0; | |
6176 | } | |
6177 | ||
0793a61d | 6178 | static const struct file_operations perf_fops = { |
3326c1ce | 6179 | .llseek = no_llseek, |
0793a61d TG |
6180 | .release = perf_release, |
6181 | .read = perf_read, | |
6182 | .poll = perf_poll, | |
d859e29f | 6183 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6184 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6185 | .mmap = perf_mmap, |
3c446b3d | 6186 | .fasync = perf_fasync, |
0793a61d TG |
6187 | }; |
6188 | ||
925d519a | 6189 | /* |
cdd6c482 | 6190 | * Perf event wakeup |
925d519a PZ |
6191 | * |
6192 | * If there's data, ensure we set the poll() state and publish everything | |
6193 | * to user-space before waking everybody up. | |
6194 | */ | |
6195 | ||
fed66e2c PZ |
6196 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6197 | { | |
6198 | /* only the parent has fasync state */ | |
6199 | if (event->parent) | |
6200 | event = event->parent; | |
6201 | return &event->fasync; | |
6202 | } | |
6203 | ||
cdd6c482 | 6204 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6205 | { |
10c6db11 | 6206 | ring_buffer_wakeup(event); |
4c9e2542 | 6207 | |
cdd6c482 | 6208 | if (event->pending_kill) { |
fed66e2c | 6209 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6210 | event->pending_kill = 0; |
4c9e2542 | 6211 | } |
925d519a PZ |
6212 | } |
6213 | ||
1d54ad94 PZ |
6214 | static void perf_pending_event_disable(struct perf_event *event) |
6215 | { | |
6216 | int cpu = READ_ONCE(event->pending_disable); | |
6217 | ||
6218 | if (cpu < 0) | |
6219 | return; | |
6220 | ||
6221 | if (cpu == smp_processor_id()) { | |
6222 | WRITE_ONCE(event->pending_disable, -1); | |
6223 | perf_event_disable_local(event); | |
6224 | return; | |
6225 | } | |
6226 | ||
6227 | /* | |
6228 | * CPU-A CPU-B | |
6229 | * | |
6230 | * perf_event_disable_inatomic() | |
6231 | * @pending_disable = CPU-A; | |
6232 | * irq_work_queue(); | |
6233 | * | |
6234 | * sched-out | |
6235 | * @pending_disable = -1; | |
6236 | * | |
6237 | * sched-in | |
6238 | * perf_event_disable_inatomic() | |
6239 | * @pending_disable = CPU-B; | |
6240 | * irq_work_queue(); // FAILS | |
6241 | * | |
6242 | * irq_work_run() | |
6243 | * perf_pending_event() | |
6244 | * | |
6245 | * But the event runs on CPU-B and wants disabling there. | |
6246 | */ | |
6247 | irq_work_queue_on(&event->pending, cpu); | |
6248 | } | |
6249 | ||
e360adbe | 6250 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6251 | { |
1d54ad94 | 6252 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6253 | int rctx; |
6254 | ||
6255 | rctx = perf_swevent_get_recursion_context(); | |
6256 | /* | |
6257 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6258 | * and we won't recurse 'further'. | |
6259 | */ | |
79f14641 | 6260 | |
1d54ad94 | 6261 | perf_pending_event_disable(event); |
79f14641 | 6262 | |
cdd6c482 IM |
6263 | if (event->pending_wakeup) { |
6264 | event->pending_wakeup = 0; | |
6265 | perf_event_wakeup(event); | |
79f14641 | 6266 | } |
d525211f PZ |
6267 | |
6268 | if (rctx >= 0) | |
6269 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6270 | } |
6271 | ||
39447b38 ZY |
6272 | /* |
6273 | * We assume there is only KVM supporting the callbacks. | |
6274 | * Later on, we might change it to a list if there is | |
6275 | * another virtualization implementation supporting the callbacks. | |
6276 | */ | |
6277 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6278 | ||
6279 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6280 | { | |
6281 | perf_guest_cbs = cbs; | |
6282 | return 0; | |
6283 | } | |
6284 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6285 | ||
6286 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6287 | { | |
6288 | perf_guest_cbs = NULL; | |
6289 | return 0; | |
6290 | } | |
6291 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6292 | ||
4018994f JO |
6293 | static void |
6294 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6295 | struct pt_regs *regs, u64 mask) | |
6296 | { | |
6297 | int bit; | |
29dd3288 | 6298 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6299 | |
29dd3288 MS |
6300 | bitmap_from_u64(_mask, mask); |
6301 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6302 | u64 val; |
6303 | ||
6304 | val = perf_reg_value(regs, bit); | |
6305 | perf_output_put(handle, val); | |
6306 | } | |
6307 | } | |
6308 | ||
60e2364e | 6309 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6310 | struct pt_regs *regs, |
6311 | struct pt_regs *regs_user_copy) | |
4018994f | 6312 | { |
88a7c26a AL |
6313 | if (user_mode(regs)) { |
6314 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6315 | regs_user->regs = regs; |
085ebfe9 | 6316 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6317 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6318 | } else { |
6319 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6320 | regs_user->regs = NULL; | |
4018994f JO |
6321 | } |
6322 | } | |
6323 | ||
60e2364e SE |
6324 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6325 | struct pt_regs *regs) | |
6326 | { | |
6327 | regs_intr->regs = regs; | |
6328 | regs_intr->abi = perf_reg_abi(current); | |
6329 | } | |
6330 | ||
6331 | ||
c5ebcedb JO |
6332 | /* |
6333 | * Get remaining task size from user stack pointer. | |
6334 | * | |
6335 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6336 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6337 | * so using TASK_SIZE as limit. |
6338 | */ | |
6339 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6340 | { | |
6341 | unsigned long addr = perf_user_stack_pointer(regs); | |
6342 | ||
6343 | if (!addr || addr >= TASK_SIZE) | |
6344 | return 0; | |
6345 | ||
6346 | return TASK_SIZE - addr; | |
6347 | } | |
6348 | ||
6349 | static u16 | |
6350 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6351 | struct pt_regs *regs) | |
6352 | { | |
6353 | u64 task_size; | |
6354 | ||
6355 | /* No regs, no stack pointer, no dump. */ | |
6356 | if (!regs) | |
6357 | return 0; | |
6358 | ||
6359 | /* | |
6360 | * Check if we fit in with the requested stack size into the: | |
6361 | * - TASK_SIZE | |
6362 | * If we don't, we limit the size to the TASK_SIZE. | |
6363 | * | |
6364 | * - remaining sample size | |
6365 | * If we don't, we customize the stack size to | |
6366 | * fit in to the remaining sample size. | |
6367 | */ | |
6368 | ||
6369 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6370 | stack_size = min(stack_size, (u16) task_size); | |
6371 | ||
6372 | /* Current header size plus static size and dynamic size. */ | |
6373 | header_size += 2 * sizeof(u64); | |
6374 | ||
6375 | /* Do we fit in with the current stack dump size? */ | |
6376 | if ((u16) (header_size + stack_size) < header_size) { | |
6377 | /* | |
6378 | * If we overflow the maximum size for the sample, | |
6379 | * we customize the stack dump size to fit in. | |
6380 | */ | |
6381 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6382 | stack_size = round_up(stack_size, sizeof(u64)); | |
6383 | } | |
6384 | ||
6385 | return stack_size; | |
6386 | } | |
6387 | ||
6388 | static void | |
6389 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6390 | struct pt_regs *regs) | |
6391 | { | |
6392 | /* Case of a kernel thread, nothing to dump */ | |
6393 | if (!regs) { | |
6394 | u64 size = 0; | |
6395 | perf_output_put(handle, size); | |
6396 | } else { | |
6397 | unsigned long sp; | |
6398 | unsigned int rem; | |
6399 | u64 dyn_size; | |
02e18447 | 6400 | mm_segment_t fs; |
c5ebcedb JO |
6401 | |
6402 | /* | |
6403 | * We dump: | |
6404 | * static size | |
6405 | * - the size requested by user or the best one we can fit | |
6406 | * in to the sample max size | |
6407 | * data | |
6408 | * - user stack dump data | |
6409 | * dynamic size | |
6410 | * - the actual dumped size | |
6411 | */ | |
6412 | ||
6413 | /* Static size. */ | |
6414 | perf_output_put(handle, dump_size); | |
6415 | ||
6416 | /* Data. */ | |
6417 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6418 | fs = get_fs(); |
6419 | set_fs(USER_DS); | |
c5ebcedb | 6420 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6421 | set_fs(fs); |
c5ebcedb JO |
6422 | dyn_size = dump_size - rem; |
6423 | ||
6424 | perf_output_skip(handle, rem); | |
6425 | ||
6426 | /* Dynamic size. */ | |
6427 | perf_output_put(handle, dyn_size); | |
6428 | } | |
6429 | } | |
6430 | ||
a4faf00d AS |
6431 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6432 | struct perf_sample_data *data, | |
6433 | size_t size) | |
6434 | { | |
6435 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6436 | struct perf_buffer *rb; |
a4faf00d AS |
6437 | |
6438 | data->aux_size = 0; | |
6439 | ||
6440 | if (!sampler) | |
6441 | goto out; | |
6442 | ||
6443 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6444 | goto out; | |
6445 | ||
6446 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6447 | goto out; | |
6448 | ||
6449 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6450 | if (!rb) | |
6451 | goto out; | |
6452 | ||
6453 | /* | |
6454 | * If this is an NMI hit inside sampling code, don't take | |
6455 | * the sample. See also perf_aux_sample_output(). | |
6456 | */ | |
6457 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6458 | data->aux_size = 0; | |
6459 | } else { | |
6460 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6461 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6462 | } | |
6463 | ring_buffer_put(rb); | |
6464 | ||
6465 | out: | |
6466 | return data->aux_size; | |
6467 | } | |
6468 | ||
56de4e8f | 6469 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6470 | struct perf_event *event, |
6471 | struct perf_output_handle *handle, | |
6472 | unsigned long size) | |
6473 | { | |
6474 | unsigned long flags; | |
6475 | long ret; | |
6476 | ||
6477 | /* | |
6478 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6479 | * paths. If we start calling them in NMI context, they may race with | |
6480 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6481 | * been stopped, which is why we're using a separate callback that | |
6482 | * doesn't change the event state. | |
6483 | * | |
6484 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6485 | */ | |
6486 | local_irq_save(flags); | |
6487 | /* | |
6488 | * Guard against NMI hits inside the critical section; | |
6489 | * see also perf_prepare_sample_aux(). | |
6490 | */ | |
6491 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6492 | barrier(); | |
6493 | ||
6494 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6495 | ||
6496 | barrier(); | |
6497 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6498 | local_irq_restore(flags); | |
6499 | ||
6500 | return ret; | |
6501 | } | |
6502 | ||
6503 | static void perf_aux_sample_output(struct perf_event *event, | |
6504 | struct perf_output_handle *handle, | |
6505 | struct perf_sample_data *data) | |
6506 | { | |
6507 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6508 | struct perf_buffer *rb; |
a4faf00d | 6509 | unsigned long pad; |
a4faf00d AS |
6510 | long size; |
6511 | ||
6512 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6513 | return; | |
6514 | ||
6515 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6516 | if (!rb) | |
6517 | return; | |
6518 | ||
6519 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6520 | ||
6521 | /* | |
6522 | * An error here means that perf_output_copy() failed (returned a | |
6523 | * non-zero surplus that it didn't copy), which in its current | |
6524 | * enlightened implementation is not possible. If that changes, we'd | |
6525 | * like to know. | |
6526 | */ | |
6527 | if (WARN_ON_ONCE(size < 0)) | |
6528 | goto out_put; | |
6529 | ||
6530 | /* | |
6531 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6532 | * perf_prepare_sample_aux(), so should not be more than that. | |
6533 | */ | |
6534 | pad = data->aux_size - size; | |
6535 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6536 | pad = 8; | |
6537 | ||
6538 | if (pad) { | |
6539 | u64 zero = 0; | |
6540 | perf_output_copy(handle, &zero, pad); | |
6541 | } | |
6542 | ||
6543 | out_put: | |
6544 | ring_buffer_put(rb); | |
6545 | } | |
6546 | ||
c980d109 ACM |
6547 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6548 | struct perf_sample_data *data, | |
6549 | struct perf_event *event) | |
6844c09d ACM |
6550 | { |
6551 | u64 sample_type = event->attr.sample_type; | |
6552 | ||
6553 | data->type = sample_type; | |
6554 | header->size += event->id_header_size; | |
6555 | ||
6556 | if (sample_type & PERF_SAMPLE_TID) { | |
6557 | /* namespace issues */ | |
6558 | data->tid_entry.pid = perf_event_pid(event, current); | |
6559 | data->tid_entry.tid = perf_event_tid(event, current); | |
6560 | } | |
6561 | ||
6562 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6563 | data->time = perf_event_clock(event); |
6844c09d | 6564 | |
ff3d527c | 6565 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6566 | data->id = primary_event_id(event); |
6567 | ||
6568 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6569 | data->stream_id = event->id; | |
6570 | ||
6571 | if (sample_type & PERF_SAMPLE_CPU) { | |
6572 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6573 | data->cpu_entry.reserved = 0; | |
6574 | } | |
6575 | } | |
6576 | ||
76369139 FW |
6577 | void perf_event_header__init_id(struct perf_event_header *header, |
6578 | struct perf_sample_data *data, | |
6579 | struct perf_event *event) | |
c980d109 ACM |
6580 | { |
6581 | if (event->attr.sample_id_all) | |
6582 | __perf_event_header__init_id(header, data, event); | |
6583 | } | |
6584 | ||
6585 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6586 | struct perf_sample_data *data) | |
6587 | { | |
6588 | u64 sample_type = data->type; | |
6589 | ||
6590 | if (sample_type & PERF_SAMPLE_TID) | |
6591 | perf_output_put(handle, data->tid_entry); | |
6592 | ||
6593 | if (sample_type & PERF_SAMPLE_TIME) | |
6594 | perf_output_put(handle, data->time); | |
6595 | ||
6596 | if (sample_type & PERF_SAMPLE_ID) | |
6597 | perf_output_put(handle, data->id); | |
6598 | ||
6599 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6600 | perf_output_put(handle, data->stream_id); | |
6601 | ||
6602 | if (sample_type & PERF_SAMPLE_CPU) | |
6603 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6604 | |
6605 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6606 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6607 | } |
6608 | ||
76369139 FW |
6609 | void perf_event__output_id_sample(struct perf_event *event, |
6610 | struct perf_output_handle *handle, | |
6611 | struct perf_sample_data *sample) | |
c980d109 ACM |
6612 | { |
6613 | if (event->attr.sample_id_all) | |
6614 | __perf_event__output_id_sample(handle, sample); | |
6615 | } | |
6616 | ||
3dab77fb | 6617 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6618 | struct perf_event *event, |
6619 | u64 enabled, u64 running) | |
3dab77fb | 6620 | { |
cdd6c482 | 6621 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6622 | u64 values[4]; |
6623 | int n = 0; | |
6624 | ||
b5e58793 | 6625 | values[n++] = perf_event_count(event); |
3dab77fb | 6626 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6627 | values[n++] = enabled + |
cdd6c482 | 6628 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6629 | } |
6630 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6631 | values[n++] = running + |
cdd6c482 | 6632 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6633 | } |
6634 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6635 | values[n++] = primary_event_id(event); |
3dab77fb | 6636 | |
76369139 | 6637 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6638 | } |
6639 | ||
3dab77fb | 6640 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6641 | struct perf_event *event, |
6642 | u64 enabled, u64 running) | |
3dab77fb | 6643 | { |
cdd6c482 IM |
6644 | struct perf_event *leader = event->group_leader, *sub; |
6645 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6646 | u64 values[5]; |
6647 | int n = 0; | |
6648 | ||
6649 | values[n++] = 1 + leader->nr_siblings; | |
6650 | ||
6651 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6652 | values[n++] = enabled; |
3dab77fb PZ |
6653 | |
6654 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6655 | values[n++] = running; |
3dab77fb | 6656 | |
9e5b127d PZ |
6657 | if ((leader != event) && |
6658 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6659 | leader->pmu->read(leader); |
6660 | ||
b5e58793 | 6661 | values[n++] = perf_event_count(leader); |
3dab77fb | 6662 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6663 | values[n++] = primary_event_id(leader); |
3dab77fb | 6664 | |
76369139 | 6665 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6666 | |
edb39592 | 6667 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6668 | n = 0; |
6669 | ||
6f5ab001 JO |
6670 | if ((sub != event) && |
6671 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6672 | sub->pmu->read(sub); |
6673 | ||
b5e58793 | 6674 | values[n++] = perf_event_count(sub); |
3dab77fb | 6675 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6676 | values[n++] = primary_event_id(sub); |
3dab77fb | 6677 | |
76369139 | 6678 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6679 | } |
6680 | } | |
6681 | ||
eed01528 SE |
6682 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6683 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6684 | ||
ba5213ae PZ |
6685 | /* |
6686 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6687 | * | |
6688 | * The problem is that its both hard and excessively expensive to iterate the | |
6689 | * child list, not to mention that its impossible to IPI the children running | |
6690 | * on another CPU, from interrupt/NMI context. | |
6691 | */ | |
3dab77fb | 6692 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6693 | struct perf_event *event) |
3dab77fb | 6694 | { |
e3f3541c | 6695 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6696 | u64 read_format = event->attr.read_format; |
6697 | ||
6698 | /* | |
6699 | * compute total_time_enabled, total_time_running | |
6700 | * based on snapshot values taken when the event | |
6701 | * was last scheduled in. | |
6702 | * | |
6703 | * we cannot simply called update_context_time() | |
6704 | * because of locking issue as we are called in | |
6705 | * NMI context | |
6706 | */ | |
c4794295 | 6707 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6708 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6709 | |
cdd6c482 | 6710 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6711 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6712 | else |
eed01528 | 6713 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6714 | } |
6715 | ||
bbfd5e4f KL |
6716 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6717 | { | |
6718 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6719 | } | |
6720 | ||
5622f295 MM |
6721 | void perf_output_sample(struct perf_output_handle *handle, |
6722 | struct perf_event_header *header, | |
6723 | struct perf_sample_data *data, | |
cdd6c482 | 6724 | struct perf_event *event) |
5622f295 MM |
6725 | { |
6726 | u64 sample_type = data->type; | |
6727 | ||
6728 | perf_output_put(handle, *header); | |
6729 | ||
ff3d527c AH |
6730 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6731 | perf_output_put(handle, data->id); | |
6732 | ||
5622f295 MM |
6733 | if (sample_type & PERF_SAMPLE_IP) |
6734 | perf_output_put(handle, data->ip); | |
6735 | ||
6736 | if (sample_type & PERF_SAMPLE_TID) | |
6737 | perf_output_put(handle, data->tid_entry); | |
6738 | ||
6739 | if (sample_type & PERF_SAMPLE_TIME) | |
6740 | perf_output_put(handle, data->time); | |
6741 | ||
6742 | if (sample_type & PERF_SAMPLE_ADDR) | |
6743 | perf_output_put(handle, data->addr); | |
6744 | ||
6745 | if (sample_type & PERF_SAMPLE_ID) | |
6746 | perf_output_put(handle, data->id); | |
6747 | ||
6748 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6749 | perf_output_put(handle, data->stream_id); | |
6750 | ||
6751 | if (sample_type & PERF_SAMPLE_CPU) | |
6752 | perf_output_put(handle, data->cpu_entry); | |
6753 | ||
6754 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6755 | perf_output_put(handle, data->period); | |
6756 | ||
6757 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6758 | perf_output_read(handle, event); |
5622f295 MM |
6759 | |
6760 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6761 | int size = 1; |
5622f295 | 6762 | |
99e818cc JO |
6763 | size += data->callchain->nr; |
6764 | size *= sizeof(u64); | |
6765 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6766 | } |
6767 | ||
6768 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6769 | struct perf_raw_record *raw = data->raw; |
6770 | ||
6771 | if (raw) { | |
6772 | struct perf_raw_frag *frag = &raw->frag; | |
6773 | ||
6774 | perf_output_put(handle, raw->size); | |
6775 | do { | |
6776 | if (frag->copy) { | |
6777 | __output_custom(handle, frag->copy, | |
6778 | frag->data, frag->size); | |
6779 | } else { | |
6780 | __output_copy(handle, frag->data, | |
6781 | frag->size); | |
6782 | } | |
6783 | if (perf_raw_frag_last(frag)) | |
6784 | break; | |
6785 | frag = frag->next; | |
6786 | } while (1); | |
6787 | if (frag->pad) | |
6788 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6789 | } else { |
6790 | struct { | |
6791 | u32 size; | |
6792 | u32 data; | |
6793 | } raw = { | |
6794 | .size = sizeof(u32), | |
6795 | .data = 0, | |
6796 | }; | |
6797 | perf_output_put(handle, raw); | |
6798 | } | |
6799 | } | |
a7ac67ea | 6800 | |
bce38cd5 SE |
6801 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6802 | if (data->br_stack) { | |
6803 | size_t size; | |
6804 | ||
6805 | size = data->br_stack->nr | |
6806 | * sizeof(struct perf_branch_entry); | |
6807 | ||
6808 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6809 | if (perf_sample_save_hw_index(event)) |
6810 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6811 | perf_output_copy(handle, data->br_stack->entries, size); |
6812 | } else { | |
6813 | /* | |
6814 | * we always store at least the value of nr | |
6815 | */ | |
6816 | u64 nr = 0; | |
6817 | perf_output_put(handle, nr); | |
6818 | } | |
6819 | } | |
4018994f JO |
6820 | |
6821 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6822 | u64 abi = data->regs_user.abi; | |
6823 | ||
6824 | /* | |
6825 | * If there are no regs to dump, notice it through | |
6826 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6827 | */ | |
6828 | perf_output_put(handle, abi); | |
6829 | ||
6830 | if (abi) { | |
6831 | u64 mask = event->attr.sample_regs_user; | |
6832 | perf_output_sample_regs(handle, | |
6833 | data->regs_user.regs, | |
6834 | mask); | |
6835 | } | |
6836 | } | |
c5ebcedb | 6837 | |
a5cdd40c | 6838 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6839 | perf_output_sample_ustack(handle, |
6840 | data->stack_user_size, | |
6841 | data->regs_user.regs); | |
a5cdd40c | 6842 | } |
c3feedf2 AK |
6843 | |
6844 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6845 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6846 | |
6847 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6848 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6849 | |
fdfbbd07 AK |
6850 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6851 | perf_output_put(handle, data->txn); | |
6852 | ||
60e2364e SE |
6853 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6854 | u64 abi = data->regs_intr.abi; | |
6855 | /* | |
6856 | * If there are no regs to dump, notice it through | |
6857 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6858 | */ | |
6859 | perf_output_put(handle, abi); | |
6860 | ||
6861 | if (abi) { | |
6862 | u64 mask = event->attr.sample_regs_intr; | |
6863 | ||
6864 | perf_output_sample_regs(handle, | |
6865 | data->regs_intr.regs, | |
6866 | mask); | |
6867 | } | |
6868 | } | |
6869 | ||
fc7ce9c7 KL |
6870 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6871 | perf_output_put(handle, data->phys_addr); | |
6872 | ||
6546b19f NK |
6873 | if (sample_type & PERF_SAMPLE_CGROUP) |
6874 | perf_output_put(handle, data->cgroup); | |
6875 | ||
a4faf00d AS |
6876 | if (sample_type & PERF_SAMPLE_AUX) { |
6877 | perf_output_put(handle, data->aux_size); | |
6878 | ||
6879 | if (data->aux_size) | |
6880 | perf_aux_sample_output(event, handle, data); | |
6881 | } | |
6882 | ||
a5cdd40c PZ |
6883 | if (!event->attr.watermark) { |
6884 | int wakeup_events = event->attr.wakeup_events; | |
6885 | ||
6886 | if (wakeup_events) { | |
56de4e8f | 6887 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6888 | int events = local_inc_return(&rb->events); |
6889 | ||
6890 | if (events >= wakeup_events) { | |
6891 | local_sub(wakeup_events, &rb->events); | |
6892 | local_inc(&rb->wakeup); | |
6893 | } | |
6894 | } | |
6895 | } | |
5622f295 MM |
6896 | } |
6897 | ||
fc7ce9c7 KL |
6898 | static u64 perf_virt_to_phys(u64 virt) |
6899 | { | |
6900 | u64 phys_addr = 0; | |
6901 | struct page *p = NULL; | |
6902 | ||
6903 | if (!virt) | |
6904 | return 0; | |
6905 | ||
6906 | if (virt >= TASK_SIZE) { | |
6907 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6908 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6909 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6910 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6911 | } else { | |
6912 | /* | |
6913 | * Walking the pages tables for user address. | |
6914 | * Interrupts are disabled, so it prevents any tear down | |
6915 | * of the page tables. | |
6916 | * Try IRQ-safe __get_user_pages_fast first. | |
6917 | * If failed, leave phys_addr as 0. | |
6918 | */ | |
6919 | if ((current->mm != NULL) && | |
6920 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6921 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6922 | ||
6923 | if (p) | |
6924 | put_page(p); | |
6925 | } | |
6926 | ||
6927 | return phys_addr; | |
6928 | } | |
6929 | ||
99e818cc JO |
6930 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6931 | ||
6cbc304f | 6932 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6933 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6934 | { | |
6935 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6936 | bool user = !event->attr.exclude_callchain_user; | |
6937 | /* Disallow cross-task user callchains. */ | |
6938 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6939 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6940 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6941 | |
6942 | if (!kernel && !user) | |
99e818cc | 6943 | return &__empty_callchain; |
8cf7e0e2 | 6944 | |
99e818cc JO |
6945 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6946 | max_stack, crosstask, true); | |
6947 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6948 | } |
6949 | ||
5622f295 MM |
6950 | void perf_prepare_sample(struct perf_event_header *header, |
6951 | struct perf_sample_data *data, | |
cdd6c482 | 6952 | struct perf_event *event, |
5622f295 | 6953 | struct pt_regs *regs) |
7b732a75 | 6954 | { |
cdd6c482 | 6955 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6956 | |
cdd6c482 | 6957 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6958 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6959 | |
6960 | header->misc = 0; | |
6961 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6962 | |
c980d109 | 6963 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6964 | |
c320c7b7 | 6965 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6966 | data->ip = perf_instruction_pointer(regs); |
6967 | ||
b23f3325 | 6968 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6969 | int size = 1; |
394ee076 | 6970 | |
6cbc304f PZ |
6971 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6972 | data->callchain = perf_callchain(event, regs); | |
6973 | ||
99e818cc | 6974 | size += data->callchain->nr; |
5622f295 MM |
6975 | |
6976 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6977 | } |
6978 | ||
3a43ce68 | 6979 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6980 | struct perf_raw_record *raw = data->raw; |
6981 | int size; | |
6982 | ||
6983 | if (raw) { | |
6984 | struct perf_raw_frag *frag = &raw->frag; | |
6985 | u32 sum = 0; | |
6986 | ||
6987 | do { | |
6988 | sum += frag->size; | |
6989 | if (perf_raw_frag_last(frag)) | |
6990 | break; | |
6991 | frag = frag->next; | |
6992 | } while (1); | |
6993 | ||
6994 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6995 | raw->size = size - sizeof(u32); | |
6996 | frag->pad = raw->size - sum; | |
6997 | } else { | |
6998 | size = sizeof(u64); | |
6999 | } | |
a044560c | 7000 | |
7e3f977e | 7001 | header->size += size; |
7f453c24 | 7002 | } |
bce38cd5 SE |
7003 | |
7004 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7005 | int size = sizeof(u64); /* nr */ | |
7006 | if (data->br_stack) { | |
bbfd5e4f KL |
7007 | if (perf_sample_save_hw_index(event)) |
7008 | size += sizeof(u64); | |
7009 | ||
bce38cd5 SE |
7010 | size += data->br_stack->nr |
7011 | * sizeof(struct perf_branch_entry); | |
7012 | } | |
7013 | header->size += size; | |
7014 | } | |
4018994f | 7015 | |
2565711f | 7016 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
7017 | perf_sample_regs_user(&data->regs_user, regs, |
7018 | &data->regs_user_copy); | |
2565711f | 7019 | |
4018994f JO |
7020 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7021 | /* regs dump ABI info */ | |
7022 | int size = sizeof(u64); | |
7023 | ||
4018994f JO |
7024 | if (data->regs_user.regs) { |
7025 | u64 mask = event->attr.sample_regs_user; | |
7026 | size += hweight64(mask) * sizeof(u64); | |
7027 | } | |
7028 | ||
7029 | header->size += size; | |
7030 | } | |
c5ebcedb JO |
7031 | |
7032 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7033 | /* | |
9f014e3a | 7034 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7035 | * processed as the last one or have additional check added |
7036 | * in case new sample type is added, because we could eat | |
7037 | * up the rest of the sample size. | |
7038 | */ | |
c5ebcedb JO |
7039 | u16 stack_size = event->attr.sample_stack_user; |
7040 | u16 size = sizeof(u64); | |
7041 | ||
c5ebcedb | 7042 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7043 | data->regs_user.regs); |
c5ebcedb JO |
7044 | |
7045 | /* | |
7046 | * If there is something to dump, add space for the dump | |
7047 | * itself and for the field that tells the dynamic size, | |
7048 | * which is how many have been actually dumped. | |
7049 | */ | |
7050 | if (stack_size) | |
7051 | size += sizeof(u64) + stack_size; | |
7052 | ||
7053 | data->stack_user_size = stack_size; | |
7054 | header->size += size; | |
7055 | } | |
60e2364e SE |
7056 | |
7057 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7058 | /* regs dump ABI info */ | |
7059 | int size = sizeof(u64); | |
7060 | ||
7061 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7062 | ||
7063 | if (data->regs_intr.regs) { | |
7064 | u64 mask = event->attr.sample_regs_intr; | |
7065 | ||
7066 | size += hweight64(mask) * sizeof(u64); | |
7067 | } | |
7068 | ||
7069 | header->size += size; | |
7070 | } | |
fc7ce9c7 KL |
7071 | |
7072 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7073 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7074 | |
6546b19f NK |
7075 | #ifdef CONFIG_CGROUP_PERF |
7076 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7077 | struct cgroup *cgrp; | |
7078 | ||
7079 | /* protected by RCU */ | |
7080 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7081 | data->cgroup = cgroup_id(cgrp); | |
7082 | } | |
7083 | #endif | |
7084 | ||
a4faf00d AS |
7085 | if (sample_type & PERF_SAMPLE_AUX) { |
7086 | u64 size; | |
7087 | ||
7088 | header->size += sizeof(u64); /* size */ | |
7089 | ||
7090 | /* | |
7091 | * Given the 16bit nature of header::size, an AUX sample can | |
7092 | * easily overflow it, what with all the preceding sample bits. | |
7093 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7094 | * per sample in total (rounded down to 8 byte boundary). | |
7095 | */ | |
7096 | size = min_t(size_t, U16_MAX - header->size, | |
7097 | event->attr.aux_sample_size); | |
7098 | size = rounddown(size, 8); | |
7099 | size = perf_prepare_sample_aux(event, data, size); | |
7100 | ||
7101 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7102 | header->size += size; | |
7103 | } | |
7104 | /* | |
7105 | * If you're adding more sample types here, you likely need to do | |
7106 | * something about the overflowing header::size, like repurpose the | |
7107 | * lowest 3 bits of size, which should be always zero at the moment. | |
7108 | * This raises a more important question, do we really need 512k sized | |
7109 | * samples and why, so good argumentation is in order for whatever you | |
7110 | * do here next. | |
7111 | */ | |
7112 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7113 | } |
7f453c24 | 7114 | |
56201969 | 7115 | static __always_inline int |
9ecda41a WN |
7116 | __perf_event_output(struct perf_event *event, |
7117 | struct perf_sample_data *data, | |
7118 | struct pt_regs *regs, | |
7119 | int (*output_begin)(struct perf_output_handle *, | |
7120 | struct perf_event *, | |
7121 | unsigned int)) | |
5622f295 MM |
7122 | { |
7123 | struct perf_output_handle handle; | |
7124 | struct perf_event_header header; | |
56201969 | 7125 | int err; |
689802b2 | 7126 | |
927c7a9e FW |
7127 | /* protect the callchain buffers */ |
7128 | rcu_read_lock(); | |
7129 | ||
cdd6c482 | 7130 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7131 | |
56201969 ACM |
7132 | err = output_begin(&handle, event, header.size); |
7133 | if (err) | |
927c7a9e | 7134 | goto exit; |
0322cd6e | 7135 | |
cdd6c482 | 7136 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7137 | |
8a057d84 | 7138 | perf_output_end(&handle); |
927c7a9e FW |
7139 | |
7140 | exit: | |
7141 | rcu_read_unlock(); | |
56201969 | 7142 | return err; |
0322cd6e PZ |
7143 | } |
7144 | ||
9ecda41a WN |
7145 | void |
7146 | perf_event_output_forward(struct perf_event *event, | |
7147 | struct perf_sample_data *data, | |
7148 | struct pt_regs *regs) | |
7149 | { | |
7150 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7151 | } | |
7152 | ||
7153 | void | |
7154 | perf_event_output_backward(struct perf_event *event, | |
7155 | struct perf_sample_data *data, | |
7156 | struct pt_regs *regs) | |
7157 | { | |
7158 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7159 | } | |
7160 | ||
56201969 | 7161 | int |
9ecda41a WN |
7162 | perf_event_output(struct perf_event *event, |
7163 | struct perf_sample_data *data, | |
7164 | struct pt_regs *regs) | |
7165 | { | |
56201969 | 7166 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7167 | } |
7168 | ||
38b200d6 | 7169 | /* |
cdd6c482 | 7170 | * read event_id |
38b200d6 PZ |
7171 | */ |
7172 | ||
7173 | struct perf_read_event { | |
7174 | struct perf_event_header header; | |
7175 | ||
7176 | u32 pid; | |
7177 | u32 tid; | |
38b200d6 PZ |
7178 | }; |
7179 | ||
7180 | static void | |
cdd6c482 | 7181 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7182 | struct task_struct *task) |
7183 | { | |
7184 | struct perf_output_handle handle; | |
c980d109 | 7185 | struct perf_sample_data sample; |
dfc65094 | 7186 | struct perf_read_event read_event = { |
38b200d6 | 7187 | .header = { |
cdd6c482 | 7188 | .type = PERF_RECORD_READ, |
38b200d6 | 7189 | .misc = 0, |
c320c7b7 | 7190 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7191 | }, |
cdd6c482 IM |
7192 | .pid = perf_event_pid(event, task), |
7193 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7194 | }; |
3dab77fb | 7195 | int ret; |
38b200d6 | 7196 | |
c980d109 | 7197 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 7198 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
7199 | if (ret) |
7200 | return; | |
7201 | ||
dfc65094 | 7202 | perf_output_put(&handle, read_event); |
cdd6c482 | 7203 | perf_output_read(&handle, event); |
c980d109 | 7204 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7205 | |
38b200d6 PZ |
7206 | perf_output_end(&handle); |
7207 | } | |
7208 | ||
aab5b71e | 7209 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7210 | |
7211 | static void | |
aab5b71e PZ |
7212 | perf_iterate_ctx(struct perf_event_context *ctx, |
7213 | perf_iterate_f output, | |
b73e4fef | 7214 | void *data, bool all) |
52d857a8 JO |
7215 | { |
7216 | struct perf_event *event; | |
7217 | ||
7218 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7219 | if (!all) { |
7220 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7221 | continue; | |
7222 | if (!event_filter_match(event)) | |
7223 | continue; | |
7224 | } | |
7225 | ||
67516844 | 7226 | output(event, data); |
52d857a8 JO |
7227 | } |
7228 | } | |
7229 | ||
aab5b71e | 7230 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7231 | { |
7232 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7233 | struct perf_event *event; | |
7234 | ||
7235 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7236 | /* |
7237 | * Skip events that are not fully formed yet; ensure that | |
7238 | * if we observe event->ctx, both event and ctx will be | |
7239 | * complete enough. See perf_install_in_context(). | |
7240 | */ | |
7241 | if (!smp_load_acquire(&event->ctx)) | |
7242 | continue; | |
7243 | ||
f2fb6bef KL |
7244 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7245 | continue; | |
7246 | if (!event_filter_match(event)) | |
7247 | continue; | |
7248 | output(event, data); | |
7249 | } | |
7250 | } | |
7251 | ||
aab5b71e PZ |
7252 | /* |
7253 | * Iterate all events that need to receive side-band events. | |
7254 | * | |
7255 | * For new callers; ensure that account_pmu_sb_event() includes | |
7256 | * your event, otherwise it might not get delivered. | |
7257 | */ | |
52d857a8 | 7258 | static void |
aab5b71e | 7259 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7260 | struct perf_event_context *task_ctx) |
7261 | { | |
52d857a8 | 7262 | struct perf_event_context *ctx; |
52d857a8 JO |
7263 | int ctxn; |
7264 | ||
aab5b71e PZ |
7265 | rcu_read_lock(); |
7266 | preempt_disable(); | |
7267 | ||
4e93ad60 | 7268 | /* |
aab5b71e PZ |
7269 | * If we have task_ctx != NULL we only notify the task context itself. |
7270 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7271 | * context. |
7272 | */ | |
7273 | if (task_ctx) { | |
aab5b71e PZ |
7274 | perf_iterate_ctx(task_ctx, output, data, false); |
7275 | goto done; | |
4e93ad60 JO |
7276 | } |
7277 | ||
aab5b71e | 7278 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7279 | |
7280 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7281 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7282 | if (ctx) | |
aab5b71e | 7283 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7284 | } |
aab5b71e | 7285 | done: |
f2fb6bef | 7286 | preempt_enable(); |
52d857a8 | 7287 | rcu_read_unlock(); |
95ff4ca2 AS |
7288 | } |
7289 | ||
375637bc AS |
7290 | /* |
7291 | * Clear all file-based filters at exec, they'll have to be | |
7292 | * re-instated when/if these objects are mmapped again. | |
7293 | */ | |
7294 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7295 | { | |
7296 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7297 | struct perf_addr_filter *filter; | |
7298 | unsigned int restart = 0, count = 0; | |
7299 | unsigned long flags; | |
7300 | ||
7301 | if (!has_addr_filter(event)) | |
7302 | return; | |
7303 | ||
7304 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7305 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7306 | if (filter->path.dentry) { |
c60f83b8 AS |
7307 | event->addr_filter_ranges[count].start = 0; |
7308 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7309 | restart++; |
7310 | } | |
7311 | ||
7312 | count++; | |
7313 | } | |
7314 | ||
7315 | if (restart) | |
7316 | event->addr_filters_gen++; | |
7317 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7318 | ||
7319 | if (restart) | |
767ae086 | 7320 | perf_event_stop(event, 1); |
375637bc AS |
7321 | } |
7322 | ||
7323 | void perf_event_exec(void) | |
7324 | { | |
7325 | struct perf_event_context *ctx; | |
7326 | int ctxn; | |
7327 | ||
7328 | rcu_read_lock(); | |
7329 | for_each_task_context_nr(ctxn) { | |
7330 | ctx = current->perf_event_ctxp[ctxn]; | |
7331 | if (!ctx) | |
7332 | continue; | |
7333 | ||
7334 | perf_event_enable_on_exec(ctxn); | |
7335 | ||
aab5b71e | 7336 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7337 | true); |
7338 | } | |
7339 | rcu_read_unlock(); | |
7340 | } | |
7341 | ||
95ff4ca2 | 7342 | struct remote_output { |
56de4e8f | 7343 | struct perf_buffer *rb; |
95ff4ca2 AS |
7344 | int err; |
7345 | }; | |
7346 | ||
7347 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7348 | { | |
7349 | struct perf_event *parent = event->parent; | |
7350 | struct remote_output *ro = data; | |
56de4e8f | 7351 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7352 | struct stop_event_data sd = { |
7353 | .event = event, | |
7354 | }; | |
95ff4ca2 AS |
7355 | |
7356 | if (!has_aux(event)) | |
7357 | return; | |
7358 | ||
7359 | if (!parent) | |
7360 | parent = event; | |
7361 | ||
7362 | /* | |
7363 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7364 | * ring-buffer, but it will be the child that's actually using it. |
7365 | * | |
7366 | * We are using event::rb to determine if the event should be stopped, | |
7367 | * however this may race with ring_buffer_attach() (through set_output), | |
7368 | * which will make us skip the event that actually needs to be stopped. | |
7369 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7370 | * its rb pointer. | |
95ff4ca2 AS |
7371 | */ |
7372 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7373 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7374 | } |
7375 | ||
7376 | static int __perf_pmu_output_stop(void *info) | |
7377 | { | |
7378 | struct perf_event *event = info; | |
f3a519e4 | 7379 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7380 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7381 | struct remote_output ro = { |
7382 | .rb = event->rb, | |
7383 | }; | |
7384 | ||
7385 | rcu_read_lock(); | |
aab5b71e | 7386 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7387 | if (cpuctx->task_ctx) |
aab5b71e | 7388 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7389 | &ro, false); |
95ff4ca2 AS |
7390 | rcu_read_unlock(); |
7391 | ||
7392 | return ro.err; | |
7393 | } | |
7394 | ||
7395 | static void perf_pmu_output_stop(struct perf_event *event) | |
7396 | { | |
7397 | struct perf_event *iter; | |
7398 | int err, cpu; | |
7399 | ||
7400 | restart: | |
7401 | rcu_read_lock(); | |
7402 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7403 | /* | |
7404 | * For per-CPU events, we need to make sure that neither they | |
7405 | * nor their children are running; for cpu==-1 events it's | |
7406 | * sufficient to stop the event itself if it's active, since | |
7407 | * it can't have children. | |
7408 | */ | |
7409 | cpu = iter->cpu; | |
7410 | if (cpu == -1) | |
7411 | cpu = READ_ONCE(iter->oncpu); | |
7412 | ||
7413 | if (cpu == -1) | |
7414 | continue; | |
7415 | ||
7416 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7417 | if (err == -EAGAIN) { | |
7418 | rcu_read_unlock(); | |
7419 | goto restart; | |
7420 | } | |
7421 | } | |
7422 | rcu_read_unlock(); | |
52d857a8 JO |
7423 | } |
7424 | ||
60313ebe | 7425 | /* |
9f498cc5 PZ |
7426 | * task tracking -- fork/exit |
7427 | * | |
13d7a241 | 7428 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7429 | */ |
7430 | ||
9f498cc5 | 7431 | struct perf_task_event { |
3a80b4a3 | 7432 | struct task_struct *task; |
cdd6c482 | 7433 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7434 | |
7435 | struct { | |
7436 | struct perf_event_header header; | |
7437 | ||
7438 | u32 pid; | |
7439 | u32 ppid; | |
9f498cc5 PZ |
7440 | u32 tid; |
7441 | u32 ptid; | |
393b2ad8 | 7442 | u64 time; |
cdd6c482 | 7443 | } event_id; |
60313ebe PZ |
7444 | }; |
7445 | ||
67516844 JO |
7446 | static int perf_event_task_match(struct perf_event *event) |
7447 | { | |
13d7a241 SE |
7448 | return event->attr.comm || event->attr.mmap || |
7449 | event->attr.mmap2 || event->attr.mmap_data || | |
7450 | event->attr.task; | |
67516844 JO |
7451 | } |
7452 | ||
cdd6c482 | 7453 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7454 | void *data) |
60313ebe | 7455 | { |
52d857a8 | 7456 | struct perf_task_event *task_event = data; |
60313ebe | 7457 | struct perf_output_handle handle; |
c980d109 | 7458 | struct perf_sample_data sample; |
9f498cc5 | 7459 | struct task_struct *task = task_event->task; |
c980d109 | 7460 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7461 | |
67516844 JO |
7462 | if (!perf_event_task_match(event)) |
7463 | return; | |
7464 | ||
c980d109 | 7465 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7466 | |
c980d109 | 7467 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7468 | task_event->event_id.header.size); |
ef60777c | 7469 | if (ret) |
c980d109 | 7470 | goto out; |
60313ebe | 7471 | |
cdd6c482 IM |
7472 | task_event->event_id.pid = perf_event_pid(event, task); |
7473 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 7474 | |
cdd6c482 IM |
7475 | task_event->event_id.tid = perf_event_tid(event, task); |
7476 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 7477 | |
34f43927 PZ |
7478 | task_event->event_id.time = perf_event_clock(event); |
7479 | ||
cdd6c482 | 7480 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7481 | |
c980d109 ACM |
7482 | perf_event__output_id_sample(event, &handle, &sample); |
7483 | ||
60313ebe | 7484 | perf_output_end(&handle); |
c980d109 ACM |
7485 | out: |
7486 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7487 | } |
7488 | ||
cdd6c482 IM |
7489 | static void perf_event_task(struct task_struct *task, |
7490 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7491 | int new) |
60313ebe | 7492 | { |
9f498cc5 | 7493 | struct perf_task_event task_event; |
60313ebe | 7494 | |
cdd6c482 IM |
7495 | if (!atomic_read(&nr_comm_events) && |
7496 | !atomic_read(&nr_mmap_events) && | |
7497 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7498 | return; |
7499 | ||
9f498cc5 | 7500 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7501 | .task = task, |
7502 | .task_ctx = task_ctx, | |
cdd6c482 | 7503 | .event_id = { |
60313ebe | 7504 | .header = { |
cdd6c482 | 7505 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7506 | .misc = 0, |
cdd6c482 | 7507 | .size = sizeof(task_event.event_id), |
60313ebe | 7508 | }, |
573402db PZ |
7509 | /* .pid */ |
7510 | /* .ppid */ | |
9f498cc5 PZ |
7511 | /* .tid */ |
7512 | /* .ptid */ | |
34f43927 | 7513 | /* .time */ |
60313ebe PZ |
7514 | }, |
7515 | }; | |
7516 | ||
aab5b71e | 7517 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7518 | &task_event, |
7519 | task_ctx); | |
9f498cc5 PZ |
7520 | } |
7521 | ||
cdd6c482 | 7522 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7523 | { |
cdd6c482 | 7524 | perf_event_task(task, NULL, 1); |
e4222673 | 7525 | perf_event_namespaces(task); |
60313ebe PZ |
7526 | } |
7527 | ||
8d1b2d93 PZ |
7528 | /* |
7529 | * comm tracking | |
7530 | */ | |
7531 | ||
7532 | struct perf_comm_event { | |
22a4f650 IM |
7533 | struct task_struct *task; |
7534 | char *comm; | |
8d1b2d93 PZ |
7535 | int comm_size; |
7536 | ||
7537 | struct { | |
7538 | struct perf_event_header header; | |
7539 | ||
7540 | u32 pid; | |
7541 | u32 tid; | |
cdd6c482 | 7542 | } event_id; |
8d1b2d93 PZ |
7543 | }; |
7544 | ||
67516844 JO |
7545 | static int perf_event_comm_match(struct perf_event *event) |
7546 | { | |
7547 | return event->attr.comm; | |
7548 | } | |
7549 | ||
cdd6c482 | 7550 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7551 | void *data) |
8d1b2d93 | 7552 | { |
52d857a8 | 7553 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7554 | struct perf_output_handle handle; |
c980d109 | 7555 | struct perf_sample_data sample; |
cdd6c482 | 7556 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7557 | int ret; |
7558 | ||
67516844 JO |
7559 | if (!perf_event_comm_match(event)) |
7560 | return; | |
7561 | ||
c980d109 ACM |
7562 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7563 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7564 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7565 | |
7566 | if (ret) | |
c980d109 | 7567 | goto out; |
8d1b2d93 | 7568 | |
cdd6c482 IM |
7569 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7570 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7571 | |
cdd6c482 | 7572 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7573 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7574 | comm_event->comm_size); |
c980d109 ACM |
7575 | |
7576 | perf_event__output_id_sample(event, &handle, &sample); | |
7577 | ||
8d1b2d93 | 7578 | perf_output_end(&handle); |
c980d109 ACM |
7579 | out: |
7580 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7581 | } |
7582 | ||
cdd6c482 | 7583 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7584 | { |
413ee3b4 | 7585 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7586 | unsigned int size; |
8d1b2d93 | 7587 | |
413ee3b4 | 7588 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7589 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7590 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7591 | |
7592 | comm_event->comm = comm; | |
7593 | comm_event->comm_size = size; | |
7594 | ||
cdd6c482 | 7595 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7596 | |
aab5b71e | 7597 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7598 | comm_event, |
7599 | NULL); | |
8d1b2d93 PZ |
7600 | } |
7601 | ||
82b89778 | 7602 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7603 | { |
9ee318a7 PZ |
7604 | struct perf_comm_event comm_event; |
7605 | ||
cdd6c482 | 7606 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7607 | return; |
a63eaf34 | 7608 | |
9ee318a7 | 7609 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7610 | .task = task, |
573402db PZ |
7611 | /* .comm */ |
7612 | /* .comm_size */ | |
cdd6c482 | 7613 | .event_id = { |
573402db | 7614 | .header = { |
cdd6c482 | 7615 | .type = PERF_RECORD_COMM, |
82b89778 | 7616 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7617 | /* .size */ |
7618 | }, | |
7619 | /* .pid */ | |
7620 | /* .tid */ | |
8d1b2d93 PZ |
7621 | }, |
7622 | }; | |
7623 | ||
cdd6c482 | 7624 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7625 | } |
7626 | ||
e4222673 HB |
7627 | /* |
7628 | * namespaces tracking | |
7629 | */ | |
7630 | ||
7631 | struct perf_namespaces_event { | |
7632 | struct task_struct *task; | |
7633 | ||
7634 | struct { | |
7635 | struct perf_event_header header; | |
7636 | ||
7637 | u32 pid; | |
7638 | u32 tid; | |
7639 | u64 nr_namespaces; | |
7640 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7641 | } event_id; | |
7642 | }; | |
7643 | ||
7644 | static int perf_event_namespaces_match(struct perf_event *event) | |
7645 | { | |
7646 | return event->attr.namespaces; | |
7647 | } | |
7648 | ||
7649 | static void perf_event_namespaces_output(struct perf_event *event, | |
7650 | void *data) | |
7651 | { | |
7652 | struct perf_namespaces_event *namespaces_event = data; | |
7653 | struct perf_output_handle handle; | |
7654 | struct perf_sample_data sample; | |
34900ec5 | 7655 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7656 | int ret; |
7657 | ||
7658 | if (!perf_event_namespaces_match(event)) | |
7659 | return; | |
7660 | ||
7661 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7662 | &sample, event); | |
7663 | ret = perf_output_begin(&handle, event, | |
7664 | namespaces_event->event_id.header.size); | |
7665 | if (ret) | |
34900ec5 | 7666 | goto out; |
e4222673 HB |
7667 | |
7668 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7669 | namespaces_event->task); | |
7670 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7671 | namespaces_event->task); | |
7672 | ||
7673 | perf_output_put(&handle, namespaces_event->event_id); | |
7674 | ||
7675 | perf_event__output_id_sample(event, &handle, &sample); | |
7676 | ||
7677 | perf_output_end(&handle); | |
34900ec5 JO |
7678 | out: |
7679 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7680 | } |
7681 | ||
7682 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7683 | struct task_struct *task, | |
7684 | const struct proc_ns_operations *ns_ops) | |
7685 | { | |
7686 | struct path ns_path; | |
7687 | struct inode *ns_inode; | |
ce623f89 | 7688 | int error; |
e4222673 HB |
7689 | |
7690 | error = ns_get_path(&ns_path, task, ns_ops); | |
7691 | if (!error) { | |
7692 | ns_inode = ns_path.dentry->d_inode; | |
7693 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7694 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7695 | path_put(&ns_path); |
e4222673 HB |
7696 | } |
7697 | } | |
7698 | ||
7699 | void perf_event_namespaces(struct task_struct *task) | |
7700 | { | |
7701 | struct perf_namespaces_event namespaces_event; | |
7702 | struct perf_ns_link_info *ns_link_info; | |
7703 | ||
7704 | if (!atomic_read(&nr_namespaces_events)) | |
7705 | return; | |
7706 | ||
7707 | namespaces_event = (struct perf_namespaces_event){ | |
7708 | .task = task, | |
7709 | .event_id = { | |
7710 | .header = { | |
7711 | .type = PERF_RECORD_NAMESPACES, | |
7712 | .misc = 0, | |
7713 | .size = sizeof(namespaces_event.event_id), | |
7714 | }, | |
7715 | /* .pid */ | |
7716 | /* .tid */ | |
7717 | .nr_namespaces = NR_NAMESPACES, | |
7718 | /* .link_info[NR_NAMESPACES] */ | |
7719 | }, | |
7720 | }; | |
7721 | ||
7722 | ns_link_info = namespaces_event.event_id.link_info; | |
7723 | ||
7724 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7725 | task, &mntns_operations); | |
7726 | ||
7727 | #ifdef CONFIG_USER_NS | |
7728 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7729 | task, &userns_operations); | |
7730 | #endif | |
7731 | #ifdef CONFIG_NET_NS | |
7732 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7733 | task, &netns_operations); | |
7734 | #endif | |
7735 | #ifdef CONFIG_UTS_NS | |
7736 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7737 | task, &utsns_operations); | |
7738 | #endif | |
7739 | #ifdef CONFIG_IPC_NS | |
7740 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7741 | task, &ipcns_operations); | |
7742 | #endif | |
7743 | #ifdef CONFIG_PID_NS | |
7744 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7745 | task, &pidns_operations); | |
7746 | #endif | |
7747 | #ifdef CONFIG_CGROUPS | |
7748 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7749 | task, &cgroupns_operations); | |
7750 | #endif | |
7751 | ||
7752 | perf_iterate_sb(perf_event_namespaces_output, | |
7753 | &namespaces_event, | |
7754 | NULL); | |
7755 | } | |
7756 | ||
96aaab68 NK |
7757 | /* |
7758 | * cgroup tracking | |
7759 | */ | |
7760 | #ifdef CONFIG_CGROUP_PERF | |
7761 | ||
7762 | struct perf_cgroup_event { | |
7763 | char *path; | |
7764 | int path_size; | |
7765 | struct { | |
7766 | struct perf_event_header header; | |
7767 | u64 id; | |
7768 | char path[]; | |
7769 | } event_id; | |
7770 | }; | |
7771 | ||
7772 | static int perf_event_cgroup_match(struct perf_event *event) | |
7773 | { | |
7774 | return event->attr.cgroup; | |
7775 | } | |
7776 | ||
7777 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
7778 | { | |
7779 | struct perf_cgroup_event *cgroup_event = data; | |
7780 | struct perf_output_handle handle; | |
7781 | struct perf_sample_data sample; | |
7782 | u16 header_size = cgroup_event->event_id.header.size; | |
7783 | int ret; | |
7784 | ||
7785 | if (!perf_event_cgroup_match(event)) | |
7786 | return; | |
7787 | ||
7788 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
7789 | &sample, event); | |
7790 | ret = perf_output_begin(&handle, event, | |
7791 | cgroup_event->event_id.header.size); | |
7792 | if (ret) | |
7793 | goto out; | |
7794 | ||
7795 | perf_output_put(&handle, cgroup_event->event_id); | |
7796 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
7797 | ||
7798 | perf_event__output_id_sample(event, &handle, &sample); | |
7799 | ||
7800 | perf_output_end(&handle); | |
7801 | out: | |
7802 | cgroup_event->event_id.header.size = header_size; | |
7803 | } | |
7804 | ||
7805 | static void perf_event_cgroup(struct cgroup *cgrp) | |
7806 | { | |
7807 | struct perf_cgroup_event cgroup_event; | |
7808 | char path_enomem[16] = "//enomem"; | |
7809 | char *pathname; | |
7810 | size_t size; | |
7811 | ||
7812 | if (!atomic_read(&nr_cgroup_events)) | |
7813 | return; | |
7814 | ||
7815 | cgroup_event = (struct perf_cgroup_event){ | |
7816 | .event_id = { | |
7817 | .header = { | |
7818 | .type = PERF_RECORD_CGROUP, | |
7819 | .misc = 0, | |
7820 | .size = sizeof(cgroup_event.event_id), | |
7821 | }, | |
7822 | .id = cgroup_id(cgrp), | |
7823 | }, | |
7824 | }; | |
7825 | ||
7826 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
7827 | if (pathname == NULL) { | |
7828 | cgroup_event.path = path_enomem; | |
7829 | } else { | |
7830 | /* just to be sure to have enough space for alignment */ | |
7831 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
7832 | cgroup_event.path = pathname; | |
7833 | } | |
7834 | ||
7835 | /* | |
7836 | * Since our buffer works in 8 byte units we need to align our string | |
7837 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7838 | * zero'd out to avoid leaking random bits to userspace. | |
7839 | */ | |
7840 | size = strlen(cgroup_event.path) + 1; | |
7841 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7842 | cgroup_event.path[size++] = '\0'; | |
7843 | ||
7844 | cgroup_event.event_id.header.size += size; | |
7845 | cgroup_event.path_size = size; | |
7846 | ||
7847 | perf_iterate_sb(perf_event_cgroup_output, | |
7848 | &cgroup_event, | |
7849 | NULL); | |
7850 | ||
7851 | kfree(pathname); | |
7852 | } | |
7853 | ||
7854 | #endif | |
7855 | ||
0a4a9391 PZ |
7856 | /* |
7857 | * mmap tracking | |
7858 | */ | |
7859 | ||
7860 | struct perf_mmap_event { | |
089dd79d PZ |
7861 | struct vm_area_struct *vma; |
7862 | ||
7863 | const char *file_name; | |
7864 | int file_size; | |
13d7a241 SE |
7865 | int maj, min; |
7866 | u64 ino; | |
7867 | u64 ino_generation; | |
f972eb63 | 7868 | u32 prot, flags; |
0a4a9391 PZ |
7869 | |
7870 | struct { | |
7871 | struct perf_event_header header; | |
7872 | ||
7873 | u32 pid; | |
7874 | u32 tid; | |
7875 | u64 start; | |
7876 | u64 len; | |
7877 | u64 pgoff; | |
cdd6c482 | 7878 | } event_id; |
0a4a9391 PZ |
7879 | }; |
7880 | ||
67516844 JO |
7881 | static int perf_event_mmap_match(struct perf_event *event, |
7882 | void *data) | |
7883 | { | |
7884 | struct perf_mmap_event *mmap_event = data; | |
7885 | struct vm_area_struct *vma = mmap_event->vma; | |
7886 | int executable = vma->vm_flags & VM_EXEC; | |
7887 | ||
7888 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7889 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7890 | } |
7891 | ||
cdd6c482 | 7892 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7893 | void *data) |
0a4a9391 | 7894 | { |
52d857a8 | 7895 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7896 | struct perf_output_handle handle; |
c980d109 | 7897 | struct perf_sample_data sample; |
cdd6c482 | 7898 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7899 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7900 | int ret; |
0a4a9391 | 7901 | |
67516844 JO |
7902 | if (!perf_event_mmap_match(event, data)) |
7903 | return; | |
7904 | ||
13d7a241 SE |
7905 | if (event->attr.mmap2) { |
7906 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7907 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7908 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7909 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7910 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7911 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7912 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7913 | } |
7914 | ||
c980d109 ACM |
7915 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7916 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7917 | mmap_event->event_id.header.size); |
0a4a9391 | 7918 | if (ret) |
c980d109 | 7919 | goto out; |
0a4a9391 | 7920 | |
cdd6c482 IM |
7921 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7922 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7923 | |
cdd6c482 | 7924 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7925 | |
7926 | if (event->attr.mmap2) { | |
7927 | perf_output_put(&handle, mmap_event->maj); | |
7928 | perf_output_put(&handle, mmap_event->min); | |
7929 | perf_output_put(&handle, mmap_event->ino); | |
7930 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7931 | perf_output_put(&handle, mmap_event->prot); |
7932 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7933 | } |
7934 | ||
76369139 | 7935 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7936 | mmap_event->file_size); |
c980d109 ACM |
7937 | |
7938 | perf_event__output_id_sample(event, &handle, &sample); | |
7939 | ||
78d613eb | 7940 | perf_output_end(&handle); |
c980d109 ACM |
7941 | out: |
7942 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7943 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7944 | } |
7945 | ||
cdd6c482 | 7946 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7947 | { |
089dd79d PZ |
7948 | struct vm_area_struct *vma = mmap_event->vma; |
7949 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7950 | int maj = 0, min = 0; |
7951 | u64 ino = 0, gen = 0; | |
f972eb63 | 7952 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7953 | unsigned int size; |
7954 | char tmp[16]; | |
7955 | char *buf = NULL; | |
2c42cfbf | 7956 | char *name; |
413ee3b4 | 7957 | |
0b3589be PZ |
7958 | if (vma->vm_flags & VM_READ) |
7959 | prot |= PROT_READ; | |
7960 | if (vma->vm_flags & VM_WRITE) | |
7961 | prot |= PROT_WRITE; | |
7962 | if (vma->vm_flags & VM_EXEC) | |
7963 | prot |= PROT_EXEC; | |
7964 | ||
7965 | if (vma->vm_flags & VM_MAYSHARE) | |
7966 | flags = MAP_SHARED; | |
7967 | else | |
7968 | flags = MAP_PRIVATE; | |
7969 | ||
7970 | if (vma->vm_flags & VM_DENYWRITE) | |
7971 | flags |= MAP_DENYWRITE; | |
7972 | if (vma->vm_flags & VM_MAYEXEC) | |
7973 | flags |= MAP_EXECUTABLE; | |
7974 | if (vma->vm_flags & VM_LOCKED) | |
7975 | flags |= MAP_LOCKED; | |
7976 | if (vma->vm_flags & VM_HUGETLB) | |
7977 | flags |= MAP_HUGETLB; | |
7978 | ||
0a4a9391 | 7979 | if (file) { |
13d7a241 SE |
7980 | struct inode *inode; |
7981 | dev_t dev; | |
3ea2f2b9 | 7982 | |
2c42cfbf | 7983 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7984 | if (!buf) { |
c7e548b4 ON |
7985 | name = "//enomem"; |
7986 | goto cpy_name; | |
0a4a9391 | 7987 | } |
413ee3b4 | 7988 | /* |
3ea2f2b9 | 7989 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7990 | * need to add enough zero bytes after the string to handle |
7991 | * the 64bit alignment we do later. | |
7992 | */ | |
9bf39ab2 | 7993 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7994 | if (IS_ERR(name)) { |
c7e548b4 ON |
7995 | name = "//toolong"; |
7996 | goto cpy_name; | |
0a4a9391 | 7997 | } |
13d7a241 SE |
7998 | inode = file_inode(vma->vm_file); |
7999 | dev = inode->i_sb->s_dev; | |
8000 | ino = inode->i_ino; | |
8001 | gen = inode->i_generation; | |
8002 | maj = MAJOR(dev); | |
8003 | min = MINOR(dev); | |
f972eb63 | 8004 | |
c7e548b4 | 8005 | goto got_name; |
0a4a9391 | 8006 | } else { |
fbe26abe JO |
8007 | if (vma->vm_ops && vma->vm_ops->name) { |
8008 | name = (char *) vma->vm_ops->name(vma); | |
8009 | if (name) | |
8010 | goto cpy_name; | |
8011 | } | |
8012 | ||
2c42cfbf | 8013 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8014 | if (name) |
8015 | goto cpy_name; | |
089dd79d | 8016 | |
32c5fb7e | 8017 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8018 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8019 | name = "[heap]"; |
8020 | goto cpy_name; | |
32c5fb7e ON |
8021 | } |
8022 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8023 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8024 | name = "[stack]"; |
8025 | goto cpy_name; | |
089dd79d PZ |
8026 | } |
8027 | ||
c7e548b4 ON |
8028 | name = "//anon"; |
8029 | goto cpy_name; | |
0a4a9391 PZ |
8030 | } |
8031 | ||
c7e548b4 ON |
8032 | cpy_name: |
8033 | strlcpy(tmp, name, sizeof(tmp)); | |
8034 | name = tmp; | |
0a4a9391 | 8035 | got_name: |
2c42cfbf PZ |
8036 | /* |
8037 | * Since our buffer works in 8 byte units we need to align our string | |
8038 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8039 | * zero'd out to avoid leaking random bits to userspace. | |
8040 | */ | |
8041 | size = strlen(name)+1; | |
8042 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8043 | name[size++] = '\0'; | |
0a4a9391 PZ |
8044 | |
8045 | mmap_event->file_name = name; | |
8046 | mmap_event->file_size = size; | |
13d7a241 SE |
8047 | mmap_event->maj = maj; |
8048 | mmap_event->min = min; | |
8049 | mmap_event->ino = ino; | |
8050 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8051 | mmap_event->prot = prot; |
8052 | mmap_event->flags = flags; | |
0a4a9391 | 8053 | |
2fe85427 SE |
8054 | if (!(vma->vm_flags & VM_EXEC)) |
8055 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8056 | ||
cdd6c482 | 8057 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8058 | |
aab5b71e | 8059 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8060 | mmap_event, |
8061 | NULL); | |
665c2142 | 8062 | |
0a4a9391 PZ |
8063 | kfree(buf); |
8064 | } | |
8065 | ||
375637bc AS |
8066 | /* |
8067 | * Check whether inode and address range match filter criteria. | |
8068 | */ | |
8069 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8070 | struct file *file, unsigned long offset, | |
8071 | unsigned long size) | |
8072 | { | |
7f635ff1 MP |
8073 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8074 | if (!filter->path.dentry) | |
8075 | return false; | |
8076 | ||
9511bce9 | 8077 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8078 | return false; |
8079 | ||
8080 | if (filter->offset > offset + size) | |
8081 | return false; | |
8082 | ||
8083 | if (filter->offset + filter->size < offset) | |
8084 | return false; | |
8085 | ||
8086 | return true; | |
8087 | } | |
8088 | ||
c60f83b8 AS |
8089 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8090 | struct vm_area_struct *vma, | |
8091 | struct perf_addr_filter_range *fr) | |
8092 | { | |
8093 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8094 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8095 | struct file *file = vma->vm_file; | |
8096 | ||
8097 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8098 | return false; | |
8099 | ||
8100 | if (filter->offset < off) { | |
8101 | fr->start = vma->vm_start; | |
8102 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8103 | } else { | |
8104 | fr->start = vma->vm_start + filter->offset - off; | |
8105 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8106 | } | |
8107 | ||
8108 | return true; | |
8109 | } | |
8110 | ||
375637bc AS |
8111 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8112 | { | |
8113 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8114 | struct vm_area_struct *vma = data; | |
375637bc AS |
8115 | struct perf_addr_filter *filter; |
8116 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8117 | unsigned long flags; |
375637bc AS |
8118 | |
8119 | if (!has_addr_filter(event)) | |
8120 | return; | |
8121 | ||
c60f83b8 | 8122 | if (!vma->vm_file) |
375637bc AS |
8123 | return; |
8124 | ||
8125 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8126 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8127 | if (perf_addr_filter_vma_adjust(filter, vma, |
8128 | &event->addr_filter_ranges[count])) | |
375637bc | 8129 | restart++; |
375637bc AS |
8130 | |
8131 | count++; | |
8132 | } | |
8133 | ||
8134 | if (restart) | |
8135 | event->addr_filters_gen++; | |
8136 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8137 | ||
8138 | if (restart) | |
767ae086 | 8139 | perf_event_stop(event, 1); |
375637bc AS |
8140 | } |
8141 | ||
8142 | /* | |
8143 | * Adjust all task's events' filters to the new vma | |
8144 | */ | |
8145 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8146 | { | |
8147 | struct perf_event_context *ctx; | |
8148 | int ctxn; | |
8149 | ||
12b40a23 MP |
8150 | /* |
8151 | * Data tracing isn't supported yet and as such there is no need | |
8152 | * to keep track of anything that isn't related to executable code: | |
8153 | */ | |
8154 | if (!(vma->vm_flags & VM_EXEC)) | |
8155 | return; | |
8156 | ||
375637bc AS |
8157 | rcu_read_lock(); |
8158 | for_each_task_context_nr(ctxn) { | |
8159 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8160 | if (!ctx) | |
8161 | continue; | |
8162 | ||
aab5b71e | 8163 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8164 | } |
8165 | rcu_read_unlock(); | |
8166 | } | |
8167 | ||
3af9e859 | 8168 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8169 | { |
9ee318a7 PZ |
8170 | struct perf_mmap_event mmap_event; |
8171 | ||
cdd6c482 | 8172 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8173 | return; |
8174 | ||
8175 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8176 | .vma = vma, |
573402db PZ |
8177 | /* .file_name */ |
8178 | /* .file_size */ | |
cdd6c482 | 8179 | .event_id = { |
573402db | 8180 | .header = { |
cdd6c482 | 8181 | .type = PERF_RECORD_MMAP, |
39447b38 | 8182 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8183 | /* .size */ |
8184 | }, | |
8185 | /* .pid */ | |
8186 | /* .tid */ | |
089dd79d PZ |
8187 | .start = vma->vm_start, |
8188 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8189 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8190 | }, |
13d7a241 SE |
8191 | /* .maj (attr_mmap2 only) */ |
8192 | /* .min (attr_mmap2 only) */ | |
8193 | /* .ino (attr_mmap2 only) */ | |
8194 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8195 | /* .prot (attr_mmap2 only) */ |
8196 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8197 | }; |
8198 | ||
375637bc | 8199 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8200 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8201 | } |
8202 | ||
68db7e98 AS |
8203 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8204 | unsigned long size, u64 flags) | |
8205 | { | |
8206 | struct perf_output_handle handle; | |
8207 | struct perf_sample_data sample; | |
8208 | struct perf_aux_event { | |
8209 | struct perf_event_header header; | |
8210 | u64 offset; | |
8211 | u64 size; | |
8212 | u64 flags; | |
8213 | } rec = { | |
8214 | .header = { | |
8215 | .type = PERF_RECORD_AUX, | |
8216 | .misc = 0, | |
8217 | .size = sizeof(rec), | |
8218 | }, | |
8219 | .offset = head, | |
8220 | .size = size, | |
8221 | .flags = flags, | |
8222 | }; | |
8223 | int ret; | |
8224 | ||
8225 | perf_event_header__init_id(&rec.header, &sample, event); | |
8226 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8227 | ||
8228 | if (ret) | |
8229 | return; | |
8230 | ||
8231 | perf_output_put(&handle, rec); | |
8232 | perf_event__output_id_sample(event, &handle, &sample); | |
8233 | ||
8234 | perf_output_end(&handle); | |
8235 | } | |
8236 | ||
f38b0dbb KL |
8237 | /* |
8238 | * Lost/dropped samples logging | |
8239 | */ | |
8240 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8241 | { | |
8242 | struct perf_output_handle handle; | |
8243 | struct perf_sample_data sample; | |
8244 | int ret; | |
8245 | ||
8246 | struct { | |
8247 | struct perf_event_header header; | |
8248 | u64 lost; | |
8249 | } lost_samples_event = { | |
8250 | .header = { | |
8251 | .type = PERF_RECORD_LOST_SAMPLES, | |
8252 | .misc = 0, | |
8253 | .size = sizeof(lost_samples_event), | |
8254 | }, | |
8255 | .lost = lost, | |
8256 | }; | |
8257 | ||
8258 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8259 | ||
8260 | ret = perf_output_begin(&handle, event, | |
8261 | lost_samples_event.header.size); | |
8262 | if (ret) | |
8263 | return; | |
8264 | ||
8265 | perf_output_put(&handle, lost_samples_event); | |
8266 | perf_event__output_id_sample(event, &handle, &sample); | |
8267 | perf_output_end(&handle); | |
8268 | } | |
8269 | ||
45ac1403 AH |
8270 | /* |
8271 | * context_switch tracking | |
8272 | */ | |
8273 | ||
8274 | struct perf_switch_event { | |
8275 | struct task_struct *task; | |
8276 | struct task_struct *next_prev; | |
8277 | ||
8278 | struct { | |
8279 | struct perf_event_header header; | |
8280 | u32 next_prev_pid; | |
8281 | u32 next_prev_tid; | |
8282 | } event_id; | |
8283 | }; | |
8284 | ||
8285 | static int perf_event_switch_match(struct perf_event *event) | |
8286 | { | |
8287 | return event->attr.context_switch; | |
8288 | } | |
8289 | ||
8290 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8291 | { | |
8292 | struct perf_switch_event *se = data; | |
8293 | struct perf_output_handle handle; | |
8294 | struct perf_sample_data sample; | |
8295 | int ret; | |
8296 | ||
8297 | if (!perf_event_switch_match(event)) | |
8298 | return; | |
8299 | ||
8300 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8301 | if (event->ctx->task) { | |
8302 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8303 | se->event_id.header.size = sizeof(se->event_id.header); | |
8304 | } else { | |
8305 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8306 | se->event_id.header.size = sizeof(se->event_id); | |
8307 | se->event_id.next_prev_pid = | |
8308 | perf_event_pid(event, se->next_prev); | |
8309 | se->event_id.next_prev_tid = | |
8310 | perf_event_tid(event, se->next_prev); | |
8311 | } | |
8312 | ||
8313 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8314 | ||
8315 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
8316 | if (ret) | |
8317 | return; | |
8318 | ||
8319 | if (event->ctx->task) | |
8320 | perf_output_put(&handle, se->event_id.header); | |
8321 | else | |
8322 | perf_output_put(&handle, se->event_id); | |
8323 | ||
8324 | perf_event__output_id_sample(event, &handle, &sample); | |
8325 | ||
8326 | perf_output_end(&handle); | |
8327 | } | |
8328 | ||
8329 | static void perf_event_switch(struct task_struct *task, | |
8330 | struct task_struct *next_prev, bool sched_in) | |
8331 | { | |
8332 | struct perf_switch_event switch_event; | |
8333 | ||
8334 | /* N.B. caller checks nr_switch_events != 0 */ | |
8335 | ||
8336 | switch_event = (struct perf_switch_event){ | |
8337 | .task = task, | |
8338 | .next_prev = next_prev, | |
8339 | .event_id = { | |
8340 | .header = { | |
8341 | /* .type */ | |
8342 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8343 | /* .size */ | |
8344 | }, | |
8345 | /* .next_prev_pid */ | |
8346 | /* .next_prev_tid */ | |
8347 | }, | |
8348 | }; | |
8349 | ||
101592b4 AB |
8350 | if (!sched_in && task->state == TASK_RUNNING) |
8351 | switch_event.event_id.header.misc |= | |
8352 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8353 | ||
aab5b71e | 8354 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8355 | &switch_event, |
8356 | NULL); | |
8357 | } | |
8358 | ||
a78ac325 PZ |
8359 | /* |
8360 | * IRQ throttle logging | |
8361 | */ | |
8362 | ||
cdd6c482 | 8363 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8364 | { |
8365 | struct perf_output_handle handle; | |
c980d109 | 8366 | struct perf_sample_data sample; |
a78ac325 PZ |
8367 | int ret; |
8368 | ||
8369 | struct { | |
8370 | struct perf_event_header header; | |
8371 | u64 time; | |
cca3f454 | 8372 | u64 id; |
7f453c24 | 8373 | u64 stream_id; |
a78ac325 PZ |
8374 | } throttle_event = { |
8375 | .header = { | |
cdd6c482 | 8376 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8377 | .misc = 0, |
8378 | .size = sizeof(throttle_event), | |
8379 | }, | |
34f43927 | 8380 | .time = perf_event_clock(event), |
cdd6c482 IM |
8381 | .id = primary_event_id(event), |
8382 | .stream_id = event->id, | |
a78ac325 PZ |
8383 | }; |
8384 | ||
966ee4d6 | 8385 | if (enable) |
cdd6c482 | 8386 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8387 | |
c980d109 ACM |
8388 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8389 | ||
8390 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 8391 | throttle_event.header.size); |
a78ac325 PZ |
8392 | if (ret) |
8393 | return; | |
8394 | ||
8395 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8396 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8397 | perf_output_end(&handle); |
8398 | } | |
8399 | ||
76193a94 SL |
8400 | /* |
8401 | * ksymbol register/unregister tracking | |
8402 | */ | |
8403 | ||
8404 | struct perf_ksymbol_event { | |
8405 | const char *name; | |
8406 | int name_len; | |
8407 | struct { | |
8408 | struct perf_event_header header; | |
8409 | u64 addr; | |
8410 | u32 len; | |
8411 | u16 ksym_type; | |
8412 | u16 flags; | |
8413 | } event_id; | |
8414 | }; | |
8415 | ||
8416 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8417 | { | |
8418 | return event->attr.ksymbol; | |
8419 | } | |
8420 | ||
8421 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8422 | { | |
8423 | struct perf_ksymbol_event *ksymbol_event = data; | |
8424 | struct perf_output_handle handle; | |
8425 | struct perf_sample_data sample; | |
8426 | int ret; | |
8427 | ||
8428 | if (!perf_event_ksymbol_match(event)) | |
8429 | return; | |
8430 | ||
8431 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8432 | &sample, event); | |
8433 | ret = perf_output_begin(&handle, event, | |
8434 | ksymbol_event->event_id.header.size); | |
8435 | if (ret) | |
8436 | return; | |
8437 | ||
8438 | perf_output_put(&handle, ksymbol_event->event_id); | |
8439 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8440 | perf_event__output_id_sample(event, &handle, &sample); | |
8441 | ||
8442 | perf_output_end(&handle); | |
8443 | } | |
8444 | ||
8445 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8446 | const char *sym) | |
8447 | { | |
8448 | struct perf_ksymbol_event ksymbol_event; | |
8449 | char name[KSYM_NAME_LEN]; | |
8450 | u16 flags = 0; | |
8451 | int name_len; | |
8452 | ||
8453 | if (!atomic_read(&nr_ksymbol_events)) | |
8454 | return; | |
8455 | ||
8456 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8457 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8458 | goto err; | |
8459 | ||
8460 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8461 | name_len = strlen(name) + 1; | |
8462 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8463 | name[name_len++] = '\0'; | |
8464 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8465 | ||
8466 | if (unregister) | |
8467 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8468 | ||
8469 | ksymbol_event = (struct perf_ksymbol_event){ | |
8470 | .name = name, | |
8471 | .name_len = name_len, | |
8472 | .event_id = { | |
8473 | .header = { | |
8474 | .type = PERF_RECORD_KSYMBOL, | |
8475 | .size = sizeof(ksymbol_event.event_id) + | |
8476 | name_len, | |
8477 | }, | |
8478 | .addr = addr, | |
8479 | .len = len, | |
8480 | .ksym_type = ksym_type, | |
8481 | .flags = flags, | |
8482 | }, | |
8483 | }; | |
8484 | ||
8485 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8486 | return; | |
8487 | err: | |
8488 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8489 | } | |
8490 | ||
6ee52e2a SL |
8491 | /* |
8492 | * bpf program load/unload tracking | |
8493 | */ | |
8494 | ||
8495 | struct perf_bpf_event { | |
8496 | struct bpf_prog *prog; | |
8497 | struct { | |
8498 | struct perf_event_header header; | |
8499 | u16 type; | |
8500 | u16 flags; | |
8501 | u32 id; | |
8502 | u8 tag[BPF_TAG_SIZE]; | |
8503 | } event_id; | |
8504 | }; | |
8505 | ||
8506 | static int perf_event_bpf_match(struct perf_event *event) | |
8507 | { | |
8508 | return event->attr.bpf_event; | |
8509 | } | |
8510 | ||
8511 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8512 | { | |
8513 | struct perf_bpf_event *bpf_event = data; | |
8514 | struct perf_output_handle handle; | |
8515 | struct perf_sample_data sample; | |
8516 | int ret; | |
8517 | ||
8518 | if (!perf_event_bpf_match(event)) | |
8519 | return; | |
8520 | ||
8521 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8522 | &sample, event); | |
8523 | ret = perf_output_begin(&handle, event, | |
8524 | bpf_event->event_id.header.size); | |
8525 | if (ret) | |
8526 | return; | |
8527 | ||
8528 | perf_output_put(&handle, bpf_event->event_id); | |
8529 | perf_event__output_id_sample(event, &handle, &sample); | |
8530 | ||
8531 | perf_output_end(&handle); | |
8532 | } | |
8533 | ||
8534 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8535 | enum perf_bpf_event_type type) | |
8536 | { | |
8537 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8538 | int i; |
8539 | ||
8540 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8541 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8542 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8543 | prog->jited_len, unregister, |
8544 | prog->aux->ksym.name); | |
6ee52e2a SL |
8545 | } else { |
8546 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8547 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8548 | ||
6ee52e2a SL |
8549 | perf_event_ksymbol( |
8550 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8551 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8552 | subprog->jited_len, unregister, |
8553 | prog->aux->ksym.name); | |
6ee52e2a SL |
8554 | } |
8555 | } | |
8556 | } | |
8557 | ||
8558 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8559 | enum perf_bpf_event_type type, | |
8560 | u16 flags) | |
8561 | { | |
8562 | struct perf_bpf_event bpf_event; | |
8563 | ||
8564 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8565 | type >= PERF_BPF_EVENT_MAX) | |
8566 | return; | |
8567 | ||
8568 | switch (type) { | |
8569 | case PERF_BPF_EVENT_PROG_LOAD: | |
8570 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8571 | if (atomic_read(&nr_ksymbol_events)) | |
8572 | perf_event_bpf_emit_ksymbols(prog, type); | |
8573 | break; | |
8574 | default: | |
8575 | break; | |
8576 | } | |
8577 | ||
8578 | if (!atomic_read(&nr_bpf_events)) | |
8579 | return; | |
8580 | ||
8581 | bpf_event = (struct perf_bpf_event){ | |
8582 | .prog = prog, | |
8583 | .event_id = { | |
8584 | .header = { | |
8585 | .type = PERF_RECORD_BPF_EVENT, | |
8586 | .size = sizeof(bpf_event.event_id), | |
8587 | }, | |
8588 | .type = type, | |
8589 | .flags = flags, | |
8590 | .id = prog->aux->id, | |
8591 | }, | |
8592 | }; | |
8593 | ||
8594 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8595 | ||
8596 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8597 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8598 | } | |
8599 | ||
8d4e6c4c AS |
8600 | void perf_event_itrace_started(struct perf_event *event) |
8601 | { | |
8602 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8603 | } | |
8604 | ||
ec0d7729 AS |
8605 | static void perf_log_itrace_start(struct perf_event *event) |
8606 | { | |
8607 | struct perf_output_handle handle; | |
8608 | struct perf_sample_data sample; | |
8609 | struct perf_aux_event { | |
8610 | struct perf_event_header header; | |
8611 | u32 pid; | |
8612 | u32 tid; | |
8613 | } rec; | |
8614 | int ret; | |
8615 | ||
8616 | if (event->parent) | |
8617 | event = event->parent; | |
8618 | ||
8619 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8620 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8621 | return; |
8622 | ||
ec0d7729 AS |
8623 | rec.header.type = PERF_RECORD_ITRACE_START; |
8624 | rec.header.misc = 0; | |
8625 | rec.header.size = sizeof(rec); | |
8626 | rec.pid = perf_event_pid(event, current); | |
8627 | rec.tid = perf_event_tid(event, current); | |
8628 | ||
8629 | perf_event_header__init_id(&rec.header, &sample, event); | |
8630 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8631 | ||
8632 | if (ret) | |
8633 | return; | |
8634 | ||
8635 | perf_output_put(&handle, rec); | |
8636 | perf_event__output_id_sample(event, &handle, &sample); | |
8637 | ||
8638 | perf_output_end(&handle); | |
8639 | } | |
8640 | ||
475113d9 JO |
8641 | static int |
8642 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8643 | { |
cdd6c482 | 8644 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8645 | int ret = 0; |
475113d9 | 8646 | u64 seq; |
96398826 | 8647 | |
e050e3f0 SE |
8648 | seq = __this_cpu_read(perf_throttled_seq); |
8649 | if (seq != hwc->interrupts_seq) { | |
8650 | hwc->interrupts_seq = seq; | |
8651 | hwc->interrupts = 1; | |
8652 | } else { | |
8653 | hwc->interrupts++; | |
8654 | if (unlikely(throttle | |
8655 | && hwc->interrupts >= max_samples_per_tick)) { | |
8656 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8657 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8658 | hwc->interrupts = MAX_INTERRUPTS; |
8659 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8660 | ret = 1; |
8661 | } | |
e050e3f0 | 8662 | } |
60db5e09 | 8663 | |
cdd6c482 | 8664 | if (event->attr.freq) { |
def0a9b2 | 8665 | u64 now = perf_clock(); |
abd50713 | 8666 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8667 | |
abd50713 | 8668 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8669 | |
abd50713 | 8670 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8671 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8672 | } |
8673 | ||
475113d9 JO |
8674 | return ret; |
8675 | } | |
8676 | ||
8677 | int perf_event_account_interrupt(struct perf_event *event) | |
8678 | { | |
8679 | return __perf_event_account_interrupt(event, 1); | |
8680 | } | |
8681 | ||
8682 | /* | |
8683 | * Generic event overflow handling, sampling. | |
8684 | */ | |
8685 | ||
8686 | static int __perf_event_overflow(struct perf_event *event, | |
8687 | int throttle, struct perf_sample_data *data, | |
8688 | struct pt_regs *regs) | |
8689 | { | |
8690 | int events = atomic_read(&event->event_limit); | |
8691 | int ret = 0; | |
8692 | ||
8693 | /* | |
8694 | * Non-sampling counters might still use the PMI to fold short | |
8695 | * hardware counters, ignore those. | |
8696 | */ | |
8697 | if (unlikely(!is_sampling_event(event))) | |
8698 | return 0; | |
8699 | ||
8700 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8701 | |
2023b359 PZ |
8702 | /* |
8703 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8704 | * events |
2023b359 PZ |
8705 | */ |
8706 | ||
cdd6c482 IM |
8707 | event->pending_kill = POLL_IN; |
8708 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8709 | ret = 1; |
cdd6c482 | 8710 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8711 | |
8712 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8713 | } |
8714 | ||
aa6a5f3c | 8715 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8716 | |
fed66e2c | 8717 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8718 | event->pending_wakeup = 1; |
8719 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8720 | } |
8721 | ||
79f14641 | 8722 | return ret; |
f6c7d5fe PZ |
8723 | } |
8724 | ||
a8b0ca17 | 8725 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8726 | struct perf_sample_data *data, |
8727 | struct pt_regs *regs) | |
850bc73f | 8728 | { |
a8b0ca17 | 8729 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8730 | } |
8731 | ||
15dbf27c | 8732 | /* |
cdd6c482 | 8733 | * Generic software event infrastructure |
15dbf27c PZ |
8734 | */ |
8735 | ||
b28ab83c PZ |
8736 | struct swevent_htable { |
8737 | struct swevent_hlist *swevent_hlist; | |
8738 | struct mutex hlist_mutex; | |
8739 | int hlist_refcount; | |
8740 | ||
8741 | /* Recursion avoidance in each contexts */ | |
8742 | int recursion[PERF_NR_CONTEXTS]; | |
8743 | }; | |
8744 | ||
8745 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8746 | ||
7b4b6658 | 8747 | /* |
cdd6c482 IM |
8748 | * We directly increment event->count and keep a second value in |
8749 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8750 | * is kept in the range [-sample_period, 0] so that we can use the |
8751 | * sign as trigger. | |
8752 | */ | |
8753 | ||
ab573844 | 8754 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8755 | { |
cdd6c482 | 8756 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8757 | u64 period = hwc->last_period; |
8758 | u64 nr, offset; | |
8759 | s64 old, val; | |
8760 | ||
8761 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8762 | |
8763 | again: | |
e7850595 | 8764 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8765 | if (val < 0) |
8766 | return 0; | |
15dbf27c | 8767 | |
7b4b6658 PZ |
8768 | nr = div64_u64(period + val, period); |
8769 | offset = nr * period; | |
8770 | val -= offset; | |
e7850595 | 8771 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8772 | goto again; |
15dbf27c | 8773 | |
7b4b6658 | 8774 | return nr; |
15dbf27c PZ |
8775 | } |
8776 | ||
0cff784a | 8777 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8778 | struct perf_sample_data *data, |
5622f295 | 8779 | struct pt_regs *regs) |
15dbf27c | 8780 | { |
cdd6c482 | 8781 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8782 | int throttle = 0; |
15dbf27c | 8783 | |
0cff784a PZ |
8784 | if (!overflow) |
8785 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8786 | |
7b4b6658 PZ |
8787 | if (hwc->interrupts == MAX_INTERRUPTS) |
8788 | return; | |
15dbf27c | 8789 | |
7b4b6658 | 8790 | for (; overflow; overflow--) { |
a8b0ca17 | 8791 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8792 | data, regs)) { |
7b4b6658 PZ |
8793 | /* |
8794 | * We inhibit the overflow from happening when | |
8795 | * hwc->interrupts == MAX_INTERRUPTS. | |
8796 | */ | |
8797 | break; | |
8798 | } | |
cf450a73 | 8799 | throttle = 1; |
7b4b6658 | 8800 | } |
15dbf27c PZ |
8801 | } |
8802 | ||
a4eaf7f1 | 8803 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8804 | struct perf_sample_data *data, |
5622f295 | 8805 | struct pt_regs *regs) |
7b4b6658 | 8806 | { |
cdd6c482 | 8807 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8808 | |
e7850595 | 8809 | local64_add(nr, &event->count); |
d6d020e9 | 8810 | |
0cff784a PZ |
8811 | if (!regs) |
8812 | return; | |
8813 | ||
6c7e550f | 8814 | if (!is_sampling_event(event)) |
7b4b6658 | 8815 | return; |
d6d020e9 | 8816 | |
5d81e5cf AV |
8817 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8818 | data->period = nr; | |
8819 | return perf_swevent_overflow(event, 1, data, regs); | |
8820 | } else | |
8821 | data->period = event->hw.last_period; | |
8822 | ||
0cff784a | 8823 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8824 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8825 | |
e7850595 | 8826 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8827 | return; |
df1a132b | 8828 | |
a8b0ca17 | 8829 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8830 | } |
8831 | ||
f5ffe02e FW |
8832 | static int perf_exclude_event(struct perf_event *event, |
8833 | struct pt_regs *regs) | |
8834 | { | |
a4eaf7f1 | 8835 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8836 | return 1; |
a4eaf7f1 | 8837 | |
f5ffe02e FW |
8838 | if (regs) { |
8839 | if (event->attr.exclude_user && user_mode(regs)) | |
8840 | return 1; | |
8841 | ||
8842 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8843 | return 1; | |
8844 | } | |
8845 | ||
8846 | return 0; | |
8847 | } | |
8848 | ||
cdd6c482 | 8849 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8850 | enum perf_type_id type, |
6fb2915d LZ |
8851 | u32 event_id, |
8852 | struct perf_sample_data *data, | |
8853 | struct pt_regs *regs) | |
15dbf27c | 8854 | { |
cdd6c482 | 8855 | if (event->attr.type != type) |
a21ca2ca | 8856 | return 0; |
f5ffe02e | 8857 | |
cdd6c482 | 8858 | if (event->attr.config != event_id) |
15dbf27c PZ |
8859 | return 0; |
8860 | ||
f5ffe02e FW |
8861 | if (perf_exclude_event(event, regs)) |
8862 | return 0; | |
15dbf27c PZ |
8863 | |
8864 | return 1; | |
8865 | } | |
8866 | ||
76e1d904 FW |
8867 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8868 | { | |
8869 | u64 val = event_id | (type << 32); | |
8870 | ||
8871 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8872 | } | |
8873 | ||
49f135ed FW |
8874 | static inline struct hlist_head * |
8875 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8876 | { |
49f135ed FW |
8877 | u64 hash = swevent_hash(type, event_id); |
8878 | ||
8879 | return &hlist->heads[hash]; | |
8880 | } | |
76e1d904 | 8881 | |
49f135ed FW |
8882 | /* For the read side: events when they trigger */ |
8883 | static inline struct hlist_head * | |
b28ab83c | 8884 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8885 | { |
8886 | struct swevent_hlist *hlist; | |
76e1d904 | 8887 | |
b28ab83c | 8888 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8889 | if (!hlist) |
8890 | return NULL; | |
8891 | ||
49f135ed FW |
8892 | return __find_swevent_head(hlist, type, event_id); |
8893 | } | |
8894 | ||
8895 | /* For the event head insertion and removal in the hlist */ | |
8896 | static inline struct hlist_head * | |
b28ab83c | 8897 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8898 | { |
8899 | struct swevent_hlist *hlist; | |
8900 | u32 event_id = event->attr.config; | |
8901 | u64 type = event->attr.type; | |
8902 | ||
8903 | /* | |
8904 | * Event scheduling is always serialized against hlist allocation | |
8905 | * and release. Which makes the protected version suitable here. | |
8906 | * The context lock guarantees that. | |
8907 | */ | |
b28ab83c | 8908 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8909 | lockdep_is_held(&event->ctx->lock)); |
8910 | if (!hlist) | |
8911 | return NULL; | |
8912 | ||
8913 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8914 | } |
8915 | ||
8916 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8917 | u64 nr, |
76e1d904 FW |
8918 | struct perf_sample_data *data, |
8919 | struct pt_regs *regs) | |
15dbf27c | 8920 | { |
4a32fea9 | 8921 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8922 | struct perf_event *event; |
76e1d904 | 8923 | struct hlist_head *head; |
15dbf27c | 8924 | |
76e1d904 | 8925 | rcu_read_lock(); |
b28ab83c | 8926 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8927 | if (!head) |
8928 | goto end; | |
8929 | ||
b67bfe0d | 8930 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8931 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8932 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8933 | } |
76e1d904 FW |
8934 | end: |
8935 | rcu_read_unlock(); | |
15dbf27c PZ |
8936 | } |
8937 | ||
86038c5e PZI |
8938 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8939 | ||
4ed7c92d | 8940 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8941 | { |
4a32fea9 | 8942 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8943 | |
b28ab83c | 8944 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8945 | } |
645e8cc0 | 8946 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8947 | |
98b5c2c6 | 8948 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8949 | { |
4a32fea9 | 8950 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8951 | |
b28ab83c | 8952 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8953 | } |
15dbf27c | 8954 | |
86038c5e | 8955 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8956 | { |
a4234bfc | 8957 | struct perf_sample_data data; |
4ed7c92d | 8958 | |
86038c5e | 8959 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8960 | return; |
a4234bfc | 8961 | |
fd0d000b | 8962 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8963 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8964 | } |
8965 | ||
8966 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8967 | { | |
8968 | int rctx; | |
8969 | ||
8970 | preempt_disable_notrace(); | |
8971 | rctx = perf_swevent_get_recursion_context(); | |
8972 | if (unlikely(rctx < 0)) | |
8973 | goto fail; | |
8974 | ||
8975 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8976 | |
8977 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8978 | fail: |
1c024eca | 8979 | preempt_enable_notrace(); |
b8e83514 PZ |
8980 | } |
8981 | ||
cdd6c482 | 8982 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8983 | { |
15dbf27c PZ |
8984 | } |
8985 | ||
a4eaf7f1 | 8986 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8987 | { |
4a32fea9 | 8988 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8989 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8990 | struct hlist_head *head; |
8991 | ||
6c7e550f | 8992 | if (is_sampling_event(event)) { |
7b4b6658 | 8993 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8994 | perf_swevent_set_period(event); |
7b4b6658 | 8995 | } |
76e1d904 | 8996 | |
a4eaf7f1 PZ |
8997 | hwc->state = !(flags & PERF_EF_START); |
8998 | ||
b28ab83c | 8999 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9000 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9001 | return -EINVAL; |
9002 | ||
9003 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9004 | perf_event_update_userpage(event); |
76e1d904 | 9005 | |
15dbf27c PZ |
9006 | return 0; |
9007 | } | |
9008 | ||
a4eaf7f1 | 9009 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9010 | { |
76e1d904 | 9011 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9012 | } |
9013 | ||
a4eaf7f1 | 9014 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9015 | { |
a4eaf7f1 | 9016 | event->hw.state = 0; |
d6d020e9 | 9017 | } |
aa9c4c0f | 9018 | |
a4eaf7f1 | 9019 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9020 | { |
a4eaf7f1 | 9021 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9022 | } |
9023 | ||
49f135ed FW |
9024 | /* Deref the hlist from the update side */ |
9025 | static inline struct swevent_hlist * | |
b28ab83c | 9026 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9027 | { |
b28ab83c PZ |
9028 | return rcu_dereference_protected(swhash->swevent_hlist, |
9029 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9030 | } |
9031 | ||
b28ab83c | 9032 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9033 | { |
b28ab83c | 9034 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9035 | |
49f135ed | 9036 | if (!hlist) |
76e1d904 FW |
9037 | return; |
9038 | ||
70691d4a | 9039 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9040 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9041 | } |
9042 | ||
3b364d7b | 9043 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9044 | { |
b28ab83c | 9045 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9046 | |
b28ab83c | 9047 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9048 | |
b28ab83c PZ |
9049 | if (!--swhash->hlist_refcount) |
9050 | swevent_hlist_release(swhash); | |
76e1d904 | 9051 | |
b28ab83c | 9052 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9053 | } |
9054 | ||
3b364d7b | 9055 | static void swevent_hlist_put(void) |
76e1d904 FW |
9056 | { |
9057 | int cpu; | |
9058 | ||
76e1d904 | 9059 | for_each_possible_cpu(cpu) |
3b364d7b | 9060 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9061 | } |
9062 | ||
3b364d7b | 9063 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9064 | { |
b28ab83c | 9065 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9066 | int err = 0; |
9067 | ||
b28ab83c | 9068 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9069 | if (!swevent_hlist_deref(swhash) && |
9070 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9071 | struct swevent_hlist *hlist; |
9072 | ||
9073 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9074 | if (!hlist) { | |
9075 | err = -ENOMEM; | |
9076 | goto exit; | |
9077 | } | |
b28ab83c | 9078 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9079 | } |
b28ab83c | 9080 | swhash->hlist_refcount++; |
9ed6060d | 9081 | exit: |
b28ab83c | 9082 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9083 | |
9084 | return err; | |
9085 | } | |
9086 | ||
3b364d7b | 9087 | static int swevent_hlist_get(void) |
76e1d904 | 9088 | { |
3b364d7b | 9089 | int err, cpu, failed_cpu; |
76e1d904 | 9090 | |
a63fbed7 | 9091 | mutex_lock(&pmus_lock); |
76e1d904 | 9092 | for_each_possible_cpu(cpu) { |
3b364d7b | 9093 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9094 | if (err) { |
9095 | failed_cpu = cpu; | |
9096 | goto fail; | |
9097 | } | |
9098 | } | |
a63fbed7 | 9099 | mutex_unlock(&pmus_lock); |
76e1d904 | 9100 | return 0; |
9ed6060d | 9101 | fail: |
76e1d904 FW |
9102 | for_each_possible_cpu(cpu) { |
9103 | if (cpu == failed_cpu) | |
9104 | break; | |
3b364d7b | 9105 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9106 | } |
a63fbed7 | 9107 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9108 | return err; |
9109 | } | |
9110 | ||
c5905afb | 9111 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9112 | |
b0a873eb PZ |
9113 | static void sw_perf_event_destroy(struct perf_event *event) |
9114 | { | |
9115 | u64 event_id = event->attr.config; | |
95476b64 | 9116 | |
b0a873eb PZ |
9117 | WARN_ON(event->parent); |
9118 | ||
c5905afb | 9119 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9120 | swevent_hlist_put(); |
b0a873eb PZ |
9121 | } |
9122 | ||
9123 | static int perf_swevent_init(struct perf_event *event) | |
9124 | { | |
8176cced | 9125 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9126 | |
9127 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9128 | return -ENOENT; | |
9129 | ||
2481c5fa SE |
9130 | /* |
9131 | * no branch sampling for software events | |
9132 | */ | |
9133 | if (has_branch_stack(event)) | |
9134 | return -EOPNOTSUPP; | |
9135 | ||
b0a873eb PZ |
9136 | switch (event_id) { |
9137 | case PERF_COUNT_SW_CPU_CLOCK: | |
9138 | case PERF_COUNT_SW_TASK_CLOCK: | |
9139 | return -ENOENT; | |
9140 | ||
9141 | default: | |
9142 | break; | |
9143 | } | |
9144 | ||
ce677831 | 9145 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9146 | return -ENOENT; |
9147 | ||
9148 | if (!event->parent) { | |
9149 | int err; | |
9150 | ||
3b364d7b | 9151 | err = swevent_hlist_get(); |
b0a873eb PZ |
9152 | if (err) |
9153 | return err; | |
9154 | ||
c5905afb | 9155 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9156 | event->destroy = sw_perf_event_destroy; |
9157 | } | |
9158 | ||
9159 | return 0; | |
9160 | } | |
9161 | ||
9162 | static struct pmu perf_swevent = { | |
89a1e187 | 9163 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9164 | |
34f43927 PZ |
9165 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9166 | ||
b0a873eb | 9167 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9168 | .add = perf_swevent_add, |
9169 | .del = perf_swevent_del, | |
9170 | .start = perf_swevent_start, | |
9171 | .stop = perf_swevent_stop, | |
1c024eca | 9172 | .read = perf_swevent_read, |
1c024eca PZ |
9173 | }; |
9174 | ||
b0a873eb PZ |
9175 | #ifdef CONFIG_EVENT_TRACING |
9176 | ||
1c024eca PZ |
9177 | static int perf_tp_filter_match(struct perf_event *event, |
9178 | struct perf_sample_data *data) | |
9179 | { | |
7e3f977e | 9180 | void *record = data->raw->frag.data; |
1c024eca | 9181 | |
b71b437e PZ |
9182 | /* only top level events have filters set */ |
9183 | if (event->parent) | |
9184 | event = event->parent; | |
9185 | ||
1c024eca PZ |
9186 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9187 | return 1; | |
9188 | return 0; | |
9189 | } | |
9190 | ||
9191 | static int perf_tp_event_match(struct perf_event *event, | |
9192 | struct perf_sample_data *data, | |
9193 | struct pt_regs *regs) | |
9194 | { | |
a0f7d0f7 FW |
9195 | if (event->hw.state & PERF_HES_STOPPED) |
9196 | return 0; | |
580d607c | 9197 | /* |
9fd2e48b | 9198 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9199 | */ |
9fd2e48b | 9200 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9201 | return 0; |
9202 | ||
9203 | if (!perf_tp_filter_match(event, data)) | |
9204 | return 0; | |
9205 | ||
9206 | return 1; | |
9207 | } | |
9208 | ||
85b67bcb AS |
9209 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9210 | struct trace_event_call *call, u64 count, | |
9211 | struct pt_regs *regs, struct hlist_head *head, | |
9212 | struct task_struct *task) | |
9213 | { | |
e87c6bc3 | 9214 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9215 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9216 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9217 | perf_swevent_put_recursion_context(rctx); |
9218 | return; | |
9219 | } | |
9220 | } | |
9221 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9222 | rctx, task); |
85b67bcb AS |
9223 | } |
9224 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9225 | ||
1e1dcd93 | 9226 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9227 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9228 | struct task_struct *task) |
95476b64 FW |
9229 | { |
9230 | struct perf_sample_data data; | |
8fd0fbbe | 9231 | struct perf_event *event; |
1c024eca | 9232 | |
95476b64 | 9233 | struct perf_raw_record raw = { |
7e3f977e DB |
9234 | .frag = { |
9235 | .size = entry_size, | |
9236 | .data = record, | |
9237 | }, | |
95476b64 FW |
9238 | }; |
9239 | ||
1e1dcd93 | 9240 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9241 | data.raw = &raw; |
9242 | ||
1e1dcd93 AS |
9243 | perf_trace_buf_update(record, event_type); |
9244 | ||
8fd0fbbe | 9245 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9246 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9247 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9248 | } |
ecc55f84 | 9249 | |
e6dab5ff AV |
9250 | /* |
9251 | * If we got specified a target task, also iterate its context and | |
9252 | * deliver this event there too. | |
9253 | */ | |
9254 | if (task && task != current) { | |
9255 | struct perf_event_context *ctx; | |
9256 | struct trace_entry *entry = record; | |
9257 | ||
9258 | rcu_read_lock(); | |
9259 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9260 | if (!ctx) | |
9261 | goto unlock; | |
9262 | ||
9263 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9264 | if (event->cpu != smp_processor_id()) |
9265 | continue; | |
e6dab5ff AV |
9266 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9267 | continue; | |
9268 | if (event->attr.config != entry->type) | |
9269 | continue; | |
9270 | if (perf_tp_event_match(event, &data, regs)) | |
9271 | perf_swevent_event(event, count, &data, regs); | |
9272 | } | |
9273 | unlock: | |
9274 | rcu_read_unlock(); | |
9275 | } | |
9276 | ||
ecc55f84 | 9277 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9278 | } |
9279 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9280 | ||
cdd6c482 | 9281 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9282 | { |
1c024eca | 9283 | perf_trace_destroy(event); |
e077df4f PZ |
9284 | } |
9285 | ||
b0a873eb | 9286 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9287 | { |
76e1d904 FW |
9288 | int err; |
9289 | ||
b0a873eb PZ |
9290 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9291 | return -ENOENT; | |
9292 | ||
2481c5fa SE |
9293 | /* |
9294 | * no branch sampling for tracepoint events | |
9295 | */ | |
9296 | if (has_branch_stack(event)) | |
9297 | return -EOPNOTSUPP; | |
9298 | ||
1c024eca PZ |
9299 | err = perf_trace_init(event); |
9300 | if (err) | |
b0a873eb | 9301 | return err; |
e077df4f | 9302 | |
cdd6c482 | 9303 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9304 | |
b0a873eb PZ |
9305 | return 0; |
9306 | } | |
9307 | ||
9308 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9309 | .task_ctx_nr = perf_sw_context, |
9310 | ||
b0a873eb | 9311 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9312 | .add = perf_trace_add, |
9313 | .del = perf_trace_del, | |
9314 | .start = perf_swevent_start, | |
9315 | .stop = perf_swevent_stop, | |
b0a873eb | 9316 | .read = perf_swevent_read, |
b0a873eb PZ |
9317 | }; |
9318 | ||
33ea4b24 | 9319 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9320 | /* |
9321 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9322 | * The flags should match following PMU_FORMAT_ATTR(). | |
9323 | * | |
9324 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9325 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9326 | * |
9327 | * The following values specify a reference counter (or semaphore in the | |
9328 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9329 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9330 | * | |
9331 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9332 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9333 | */ |
9334 | enum perf_probe_config { | |
9335 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9336 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9337 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9338 | }; |
9339 | ||
9340 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9341 | #endif |
e12f03d7 | 9342 | |
a6ca88b2 SL |
9343 | #ifdef CONFIG_KPROBE_EVENTS |
9344 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9345 | &format_attr_retprobe.attr, |
9346 | NULL, | |
9347 | }; | |
9348 | ||
a6ca88b2 | 9349 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9350 | .name = "format", |
a6ca88b2 | 9351 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9352 | }; |
9353 | ||
a6ca88b2 SL |
9354 | static const struct attribute_group *kprobe_attr_groups[] = { |
9355 | &kprobe_format_group, | |
e12f03d7 SL |
9356 | NULL, |
9357 | }; | |
9358 | ||
9359 | static int perf_kprobe_event_init(struct perf_event *event); | |
9360 | static struct pmu perf_kprobe = { | |
9361 | .task_ctx_nr = perf_sw_context, | |
9362 | .event_init = perf_kprobe_event_init, | |
9363 | .add = perf_trace_add, | |
9364 | .del = perf_trace_del, | |
9365 | .start = perf_swevent_start, | |
9366 | .stop = perf_swevent_stop, | |
9367 | .read = perf_swevent_read, | |
a6ca88b2 | 9368 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9369 | }; |
9370 | ||
9371 | static int perf_kprobe_event_init(struct perf_event *event) | |
9372 | { | |
9373 | int err; | |
9374 | bool is_retprobe; | |
9375 | ||
9376 | if (event->attr.type != perf_kprobe.type) | |
9377 | return -ENOENT; | |
32e6e967 SL |
9378 | |
9379 | if (!capable(CAP_SYS_ADMIN)) | |
9380 | return -EACCES; | |
9381 | ||
e12f03d7 SL |
9382 | /* |
9383 | * no branch sampling for probe events | |
9384 | */ | |
9385 | if (has_branch_stack(event)) | |
9386 | return -EOPNOTSUPP; | |
9387 | ||
9388 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9389 | err = perf_kprobe_init(event, is_retprobe); | |
9390 | if (err) | |
9391 | return err; | |
9392 | ||
9393 | event->destroy = perf_kprobe_destroy; | |
9394 | ||
9395 | return 0; | |
9396 | } | |
9397 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9398 | ||
33ea4b24 | 9399 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9400 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9401 | ||
9402 | static struct attribute *uprobe_attrs[] = { | |
9403 | &format_attr_retprobe.attr, | |
9404 | &format_attr_ref_ctr_offset.attr, | |
9405 | NULL, | |
9406 | }; | |
9407 | ||
9408 | static struct attribute_group uprobe_format_group = { | |
9409 | .name = "format", | |
9410 | .attrs = uprobe_attrs, | |
9411 | }; | |
9412 | ||
9413 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9414 | &uprobe_format_group, | |
9415 | NULL, | |
9416 | }; | |
9417 | ||
33ea4b24 SL |
9418 | static int perf_uprobe_event_init(struct perf_event *event); |
9419 | static struct pmu perf_uprobe = { | |
9420 | .task_ctx_nr = perf_sw_context, | |
9421 | .event_init = perf_uprobe_event_init, | |
9422 | .add = perf_trace_add, | |
9423 | .del = perf_trace_del, | |
9424 | .start = perf_swevent_start, | |
9425 | .stop = perf_swevent_stop, | |
9426 | .read = perf_swevent_read, | |
a6ca88b2 | 9427 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9428 | }; |
9429 | ||
9430 | static int perf_uprobe_event_init(struct perf_event *event) | |
9431 | { | |
9432 | int err; | |
a6ca88b2 | 9433 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9434 | bool is_retprobe; |
9435 | ||
9436 | if (event->attr.type != perf_uprobe.type) | |
9437 | return -ENOENT; | |
32e6e967 SL |
9438 | |
9439 | if (!capable(CAP_SYS_ADMIN)) | |
9440 | return -EACCES; | |
9441 | ||
33ea4b24 SL |
9442 | /* |
9443 | * no branch sampling for probe events | |
9444 | */ | |
9445 | if (has_branch_stack(event)) | |
9446 | return -EOPNOTSUPP; | |
9447 | ||
9448 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9449 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9450 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9451 | if (err) |
9452 | return err; | |
9453 | ||
9454 | event->destroy = perf_uprobe_destroy; | |
9455 | ||
9456 | return 0; | |
9457 | } | |
9458 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9459 | ||
b0a873eb PZ |
9460 | static inline void perf_tp_register(void) |
9461 | { | |
2e80a82a | 9462 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9463 | #ifdef CONFIG_KPROBE_EVENTS |
9464 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9465 | #endif | |
33ea4b24 SL |
9466 | #ifdef CONFIG_UPROBE_EVENTS |
9467 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9468 | #endif | |
e077df4f | 9469 | } |
6fb2915d | 9470 | |
6fb2915d LZ |
9471 | static void perf_event_free_filter(struct perf_event *event) |
9472 | { | |
9473 | ftrace_profile_free_filter(event); | |
9474 | } | |
9475 | ||
aa6a5f3c AS |
9476 | #ifdef CONFIG_BPF_SYSCALL |
9477 | static void bpf_overflow_handler(struct perf_event *event, | |
9478 | struct perf_sample_data *data, | |
9479 | struct pt_regs *regs) | |
9480 | { | |
9481 | struct bpf_perf_event_data_kern ctx = { | |
9482 | .data = data, | |
7d9285e8 | 9483 | .event = event, |
aa6a5f3c AS |
9484 | }; |
9485 | int ret = 0; | |
9486 | ||
c895f6f7 | 9487 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9488 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9489 | goto out; | |
9490 | rcu_read_lock(); | |
88575199 | 9491 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9492 | rcu_read_unlock(); |
9493 | out: | |
9494 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9495 | if (!ret) |
9496 | return; | |
9497 | ||
9498 | event->orig_overflow_handler(event, data, regs); | |
9499 | } | |
9500 | ||
9501 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9502 | { | |
9503 | struct bpf_prog *prog; | |
9504 | ||
9505 | if (event->overflow_handler_context) | |
9506 | /* hw breakpoint or kernel counter */ | |
9507 | return -EINVAL; | |
9508 | ||
9509 | if (event->prog) | |
9510 | return -EEXIST; | |
9511 | ||
9512 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9513 | if (IS_ERR(prog)) | |
9514 | return PTR_ERR(prog); | |
9515 | ||
9516 | event->prog = prog; | |
9517 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9518 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9519 | return 0; | |
9520 | } | |
9521 | ||
9522 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9523 | { | |
9524 | struct bpf_prog *prog = event->prog; | |
9525 | ||
9526 | if (!prog) | |
9527 | return; | |
9528 | ||
9529 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9530 | event->prog = NULL; | |
9531 | bpf_prog_put(prog); | |
9532 | } | |
9533 | #else | |
9534 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9535 | { | |
9536 | return -EOPNOTSUPP; | |
9537 | } | |
9538 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9539 | { | |
9540 | } | |
9541 | #endif | |
9542 | ||
e12f03d7 SL |
9543 | /* |
9544 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9545 | * with perf_event_open() | |
9546 | */ | |
9547 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9548 | { | |
9549 | if (event->pmu == &perf_tracepoint) | |
9550 | return true; | |
9551 | #ifdef CONFIG_KPROBE_EVENTS | |
9552 | if (event->pmu == &perf_kprobe) | |
9553 | return true; | |
33ea4b24 SL |
9554 | #endif |
9555 | #ifdef CONFIG_UPROBE_EVENTS | |
9556 | if (event->pmu == &perf_uprobe) | |
9557 | return true; | |
e12f03d7 SL |
9558 | #endif |
9559 | return false; | |
9560 | } | |
9561 | ||
2541517c AS |
9562 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9563 | { | |
cf5f5cea | 9564 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9565 | struct bpf_prog *prog; |
e87c6bc3 | 9566 | int ret; |
2541517c | 9567 | |
e12f03d7 | 9568 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9569 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9570 | |
98b5c2c6 AS |
9571 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9572 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9573 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9574 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9575 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9576 | return -EINVAL; |
9577 | ||
9578 | prog = bpf_prog_get(prog_fd); | |
9579 | if (IS_ERR(prog)) | |
9580 | return PTR_ERR(prog); | |
9581 | ||
98b5c2c6 | 9582 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9583 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9584 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9585 | /* valid fd, but invalid bpf program type */ |
9586 | bpf_prog_put(prog); | |
9587 | return -EINVAL; | |
9588 | } | |
9589 | ||
9802d865 JB |
9590 | /* Kprobe override only works for kprobes, not uprobes. */ |
9591 | if (prog->kprobe_override && | |
9592 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9593 | bpf_prog_put(prog); | |
9594 | return -EINVAL; | |
9595 | } | |
9596 | ||
cf5f5cea | 9597 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9598 | int off = trace_event_get_offsets(event->tp_event); |
9599 | ||
9600 | if (prog->aux->max_ctx_offset > off) { | |
9601 | bpf_prog_put(prog); | |
9602 | return -EACCES; | |
9603 | } | |
9604 | } | |
2541517c | 9605 | |
e87c6bc3 YS |
9606 | ret = perf_event_attach_bpf_prog(event, prog); |
9607 | if (ret) | |
9608 | bpf_prog_put(prog); | |
9609 | return ret; | |
2541517c AS |
9610 | } |
9611 | ||
9612 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9613 | { | |
e12f03d7 | 9614 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9615 | perf_event_free_bpf_handler(event); |
2541517c | 9616 | return; |
2541517c | 9617 | } |
e87c6bc3 | 9618 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9619 | } |
9620 | ||
e077df4f | 9621 | #else |
6fb2915d | 9622 | |
b0a873eb | 9623 | static inline void perf_tp_register(void) |
e077df4f | 9624 | { |
e077df4f | 9625 | } |
6fb2915d | 9626 | |
6fb2915d LZ |
9627 | static void perf_event_free_filter(struct perf_event *event) |
9628 | { | |
9629 | } | |
9630 | ||
2541517c AS |
9631 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9632 | { | |
9633 | return -ENOENT; | |
9634 | } | |
9635 | ||
9636 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9637 | { | |
9638 | } | |
07b139c8 | 9639 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9640 | |
24f1e32c | 9641 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9642 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9643 | { |
f5ffe02e FW |
9644 | struct perf_sample_data sample; |
9645 | struct pt_regs *regs = data; | |
9646 | ||
fd0d000b | 9647 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9648 | |
a4eaf7f1 | 9649 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9650 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9651 | } |
9652 | #endif | |
9653 | ||
375637bc AS |
9654 | /* |
9655 | * Allocate a new address filter | |
9656 | */ | |
9657 | static struct perf_addr_filter * | |
9658 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9659 | { | |
9660 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9661 | struct perf_addr_filter *filter; | |
9662 | ||
9663 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9664 | if (!filter) | |
9665 | return NULL; | |
9666 | ||
9667 | INIT_LIST_HEAD(&filter->entry); | |
9668 | list_add_tail(&filter->entry, filters); | |
9669 | ||
9670 | return filter; | |
9671 | } | |
9672 | ||
9673 | static void free_filters_list(struct list_head *filters) | |
9674 | { | |
9675 | struct perf_addr_filter *filter, *iter; | |
9676 | ||
9677 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9678 | path_put(&filter->path); |
375637bc AS |
9679 | list_del(&filter->entry); |
9680 | kfree(filter); | |
9681 | } | |
9682 | } | |
9683 | ||
9684 | /* | |
9685 | * Free existing address filters and optionally install new ones | |
9686 | */ | |
9687 | static void perf_addr_filters_splice(struct perf_event *event, | |
9688 | struct list_head *head) | |
9689 | { | |
9690 | unsigned long flags; | |
9691 | LIST_HEAD(list); | |
9692 | ||
9693 | if (!has_addr_filter(event)) | |
9694 | return; | |
9695 | ||
9696 | /* don't bother with children, they don't have their own filters */ | |
9697 | if (event->parent) | |
9698 | return; | |
9699 | ||
9700 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9701 | ||
9702 | list_splice_init(&event->addr_filters.list, &list); | |
9703 | if (head) | |
9704 | list_splice(head, &event->addr_filters.list); | |
9705 | ||
9706 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9707 | ||
9708 | free_filters_list(&list); | |
9709 | } | |
9710 | ||
9711 | /* | |
9712 | * Scan through mm's vmas and see if one of them matches the | |
9713 | * @filter; if so, adjust filter's address range. | |
9714 | * Called with mm::mmap_sem down for reading. | |
9715 | */ | |
c60f83b8 AS |
9716 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9717 | struct mm_struct *mm, | |
9718 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9719 | { |
9720 | struct vm_area_struct *vma; | |
9721 | ||
9722 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9723 | if (!vma->vm_file) |
375637bc AS |
9724 | continue; |
9725 | ||
c60f83b8 AS |
9726 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9727 | return; | |
375637bc | 9728 | } |
375637bc AS |
9729 | } |
9730 | ||
9731 | /* | |
9732 | * Update event's address range filters based on the | |
9733 | * task's existing mappings, if any. | |
9734 | */ | |
9735 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9736 | { | |
9737 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9738 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9739 | struct perf_addr_filter *filter; | |
9740 | struct mm_struct *mm = NULL; | |
9741 | unsigned int count = 0; | |
9742 | unsigned long flags; | |
9743 | ||
9744 | /* | |
9745 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9746 | * will stop on the parent's child_mutex that our caller is also holding | |
9747 | */ | |
9748 | if (task == TASK_TOMBSTONE) | |
9749 | return; | |
9750 | ||
52a44f83 AS |
9751 | if (ifh->nr_file_filters) { |
9752 | mm = get_task_mm(event->ctx->task); | |
9753 | if (!mm) | |
9754 | goto restart; | |
375637bc | 9755 | |
52a44f83 AS |
9756 | down_read(&mm->mmap_sem); |
9757 | } | |
375637bc AS |
9758 | |
9759 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9760 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9761 | if (filter->path.dentry) { |
9762 | /* | |
9763 | * Adjust base offset if the filter is associated to a | |
9764 | * binary that needs to be mapped: | |
9765 | */ | |
9766 | event->addr_filter_ranges[count].start = 0; | |
9767 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9768 | |
c60f83b8 | 9769 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9770 | } else { |
9771 | event->addr_filter_ranges[count].start = filter->offset; | |
9772 | event->addr_filter_ranges[count].size = filter->size; | |
9773 | } | |
375637bc AS |
9774 | |
9775 | count++; | |
9776 | } | |
9777 | ||
9778 | event->addr_filters_gen++; | |
9779 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9780 | ||
52a44f83 AS |
9781 | if (ifh->nr_file_filters) { |
9782 | up_read(&mm->mmap_sem); | |
375637bc | 9783 | |
52a44f83 AS |
9784 | mmput(mm); |
9785 | } | |
375637bc AS |
9786 | |
9787 | restart: | |
767ae086 | 9788 | perf_event_stop(event, 1); |
375637bc AS |
9789 | } |
9790 | ||
9791 | /* | |
9792 | * Address range filtering: limiting the data to certain | |
9793 | * instruction address ranges. Filters are ioctl()ed to us from | |
9794 | * userspace as ascii strings. | |
9795 | * | |
9796 | * Filter string format: | |
9797 | * | |
9798 | * ACTION RANGE_SPEC | |
9799 | * where ACTION is one of the | |
9800 | * * "filter": limit the trace to this region | |
9801 | * * "start": start tracing from this address | |
9802 | * * "stop": stop tracing at this address/region; | |
9803 | * RANGE_SPEC is | |
9804 | * * for kernel addresses: <start address>[/<size>] | |
9805 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9806 | * | |
6ed70cf3 AS |
9807 | * if <size> is not specified or is zero, the range is treated as a single |
9808 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9809 | */ |
9810 | enum { | |
e96271f3 | 9811 | IF_ACT_NONE = -1, |
375637bc AS |
9812 | IF_ACT_FILTER, |
9813 | IF_ACT_START, | |
9814 | IF_ACT_STOP, | |
9815 | IF_SRC_FILE, | |
9816 | IF_SRC_KERNEL, | |
9817 | IF_SRC_FILEADDR, | |
9818 | IF_SRC_KERNELADDR, | |
9819 | }; | |
9820 | ||
9821 | enum { | |
9822 | IF_STATE_ACTION = 0, | |
9823 | IF_STATE_SOURCE, | |
9824 | IF_STATE_END, | |
9825 | }; | |
9826 | ||
9827 | static const match_table_t if_tokens = { | |
9828 | { IF_ACT_FILTER, "filter" }, | |
9829 | { IF_ACT_START, "start" }, | |
9830 | { IF_ACT_STOP, "stop" }, | |
9831 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9832 | { IF_SRC_KERNEL, "%u/%u" }, | |
9833 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9834 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9835 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9836 | }; |
9837 | ||
9838 | /* | |
9839 | * Address filter string parser | |
9840 | */ | |
9841 | static int | |
9842 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9843 | struct list_head *filters) | |
9844 | { | |
9845 | struct perf_addr_filter *filter = NULL; | |
9846 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9847 | substring_t args[MAX_OPT_ARGS]; |
9848 | int state = IF_STATE_ACTION, token; | |
9849 | unsigned int kernel = 0; | |
9850 | int ret = -EINVAL; | |
9851 | ||
9852 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9853 | if (!fstr) | |
9854 | return -ENOMEM; | |
9855 | ||
9856 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9857 | static const enum perf_addr_filter_action_t actions[] = { |
9858 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9859 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9860 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9861 | }; | |
375637bc AS |
9862 | ret = -EINVAL; |
9863 | ||
9864 | if (!*start) | |
9865 | continue; | |
9866 | ||
9867 | /* filter definition begins */ | |
9868 | if (state == IF_STATE_ACTION) { | |
9869 | filter = perf_addr_filter_new(event, filters); | |
9870 | if (!filter) | |
9871 | goto fail; | |
9872 | } | |
9873 | ||
9874 | token = match_token(start, if_tokens, args); | |
9875 | switch (token) { | |
9876 | case IF_ACT_FILTER: | |
9877 | case IF_ACT_START: | |
375637bc AS |
9878 | case IF_ACT_STOP: |
9879 | if (state != IF_STATE_ACTION) | |
9880 | goto fail; | |
9881 | ||
6ed70cf3 | 9882 | filter->action = actions[token]; |
375637bc AS |
9883 | state = IF_STATE_SOURCE; |
9884 | break; | |
9885 | ||
9886 | case IF_SRC_KERNELADDR: | |
9887 | case IF_SRC_KERNEL: | |
9888 | kernel = 1; | |
10c3405f | 9889 | /* fall through */ |
375637bc AS |
9890 | |
9891 | case IF_SRC_FILEADDR: | |
9892 | case IF_SRC_FILE: | |
9893 | if (state != IF_STATE_SOURCE) | |
9894 | goto fail; | |
9895 | ||
375637bc AS |
9896 | *args[0].to = 0; |
9897 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9898 | if (ret) | |
9899 | goto fail; | |
9900 | ||
6ed70cf3 | 9901 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9902 | *args[1].to = 0; |
9903 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9904 | if (ret) | |
9905 | goto fail; | |
9906 | } | |
9907 | ||
4059ffd0 | 9908 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9909 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9910 | |
9911 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9912 | if (!filename) { |
9913 | ret = -ENOMEM; | |
9914 | goto fail; | |
9915 | } | |
9916 | } | |
9917 | ||
9918 | state = IF_STATE_END; | |
9919 | break; | |
9920 | ||
9921 | default: | |
9922 | goto fail; | |
9923 | } | |
9924 | ||
9925 | /* | |
9926 | * Filter definition is fully parsed, validate and install it. | |
9927 | * Make sure that it doesn't contradict itself or the event's | |
9928 | * attribute. | |
9929 | */ | |
9930 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9931 | ret = -EINVAL; |
375637bc AS |
9932 | if (kernel && event->attr.exclude_kernel) |
9933 | goto fail; | |
9934 | ||
6ed70cf3 AS |
9935 | /* |
9936 | * ACTION "filter" must have a non-zero length region | |
9937 | * specified. | |
9938 | */ | |
9939 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9940 | !filter->size) | |
9941 | goto fail; | |
9942 | ||
375637bc AS |
9943 | if (!kernel) { |
9944 | if (!filename) | |
9945 | goto fail; | |
9946 | ||
6ce77bfd AS |
9947 | /* |
9948 | * For now, we only support file-based filters | |
9949 | * in per-task events; doing so for CPU-wide | |
9950 | * events requires additional context switching | |
9951 | * trickery, since same object code will be | |
9952 | * mapped at different virtual addresses in | |
9953 | * different processes. | |
9954 | */ | |
9955 | ret = -EOPNOTSUPP; | |
9956 | if (!event->ctx->task) | |
9957 | goto fail_free_name; | |
9958 | ||
375637bc | 9959 | /* look up the path and grab its inode */ |
9511bce9 SL |
9960 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9961 | &filter->path); | |
375637bc AS |
9962 | if (ret) |
9963 | goto fail_free_name; | |
9964 | ||
375637bc AS |
9965 | kfree(filename); |
9966 | filename = NULL; | |
9967 | ||
9968 | ret = -EINVAL; | |
9511bce9 SL |
9969 | if (!filter->path.dentry || |
9970 | !S_ISREG(d_inode(filter->path.dentry) | |
9971 | ->i_mode)) | |
375637bc | 9972 | goto fail; |
6ce77bfd AS |
9973 | |
9974 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9975 | } |
9976 | ||
9977 | /* ready to consume more filters */ | |
9978 | state = IF_STATE_ACTION; | |
9979 | filter = NULL; | |
9980 | } | |
9981 | } | |
9982 | ||
9983 | if (state != IF_STATE_ACTION) | |
9984 | goto fail; | |
9985 | ||
9986 | kfree(orig); | |
9987 | ||
9988 | return 0; | |
9989 | ||
9990 | fail_free_name: | |
9991 | kfree(filename); | |
9992 | fail: | |
9993 | free_filters_list(filters); | |
9994 | kfree(orig); | |
9995 | ||
9996 | return ret; | |
9997 | } | |
9998 | ||
9999 | static int | |
10000 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10001 | { | |
10002 | LIST_HEAD(filters); | |
10003 | int ret; | |
10004 | ||
10005 | /* | |
10006 | * Since this is called in perf_ioctl() path, we're already holding | |
10007 | * ctx::mutex. | |
10008 | */ | |
10009 | lockdep_assert_held(&event->ctx->mutex); | |
10010 | ||
10011 | if (WARN_ON_ONCE(event->parent)) | |
10012 | return -EINVAL; | |
10013 | ||
375637bc AS |
10014 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10015 | if (ret) | |
6ce77bfd | 10016 | goto fail_clear_files; |
375637bc AS |
10017 | |
10018 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10019 | if (ret) |
10020 | goto fail_free_filters; | |
375637bc AS |
10021 | |
10022 | /* remove existing filters, if any */ | |
10023 | perf_addr_filters_splice(event, &filters); | |
10024 | ||
10025 | /* install new filters */ | |
10026 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10027 | ||
6ce77bfd AS |
10028 | return ret; |
10029 | ||
10030 | fail_free_filters: | |
10031 | free_filters_list(&filters); | |
10032 | ||
10033 | fail_clear_files: | |
10034 | event->addr_filters.nr_file_filters = 0; | |
10035 | ||
375637bc AS |
10036 | return ret; |
10037 | } | |
10038 | ||
c796bbbe AS |
10039 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10040 | { | |
c796bbbe | 10041 | int ret = -EINVAL; |
e12f03d7 | 10042 | char *filter_str; |
c796bbbe AS |
10043 | |
10044 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10045 | if (IS_ERR(filter_str)) | |
10046 | return PTR_ERR(filter_str); | |
10047 | ||
e12f03d7 SL |
10048 | #ifdef CONFIG_EVENT_TRACING |
10049 | if (perf_event_is_tracing(event)) { | |
10050 | struct perf_event_context *ctx = event->ctx; | |
10051 | ||
10052 | /* | |
10053 | * Beware, here be dragons!! | |
10054 | * | |
10055 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10056 | * the tracepoint stuff does not actually need it. So | |
10057 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10058 | * already have a reference on ctx. | |
10059 | * | |
10060 | * This can result in event getting moved to a different ctx, | |
10061 | * but that does not affect the tracepoint state. | |
10062 | */ | |
10063 | mutex_unlock(&ctx->mutex); | |
10064 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10065 | mutex_lock(&ctx->mutex); | |
10066 | } else | |
10067 | #endif | |
10068 | if (has_addr_filter(event)) | |
375637bc | 10069 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10070 | |
10071 | kfree(filter_str); | |
10072 | return ret; | |
10073 | } | |
10074 | ||
b0a873eb PZ |
10075 | /* |
10076 | * hrtimer based swevent callback | |
10077 | */ | |
f29ac756 | 10078 | |
b0a873eb | 10079 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10080 | { |
b0a873eb PZ |
10081 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10082 | struct perf_sample_data data; | |
10083 | struct pt_regs *regs; | |
10084 | struct perf_event *event; | |
10085 | u64 period; | |
f29ac756 | 10086 | |
b0a873eb | 10087 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10088 | |
10089 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10090 | return HRTIMER_NORESTART; | |
10091 | ||
b0a873eb | 10092 | event->pmu->read(event); |
f344011c | 10093 | |
fd0d000b | 10094 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10095 | regs = get_irq_regs(); |
10096 | ||
10097 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10098 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10099 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10100 | ret = HRTIMER_NORESTART; |
10101 | } | |
24f1e32c | 10102 | |
b0a873eb PZ |
10103 | period = max_t(u64, 10000, event->hw.sample_period); |
10104 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10105 | |
b0a873eb | 10106 | return ret; |
f29ac756 PZ |
10107 | } |
10108 | ||
b0a873eb | 10109 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10110 | { |
b0a873eb | 10111 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10112 | s64 period; |
10113 | ||
10114 | if (!is_sampling_event(event)) | |
10115 | return; | |
f5ffe02e | 10116 | |
5d508e82 FBH |
10117 | period = local64_read(&hwc->period_left); |
10118 | if (period) { | |
10119 | if (period < 0) | |
10120 | period = 10000; | |
fa407f35 | 10121 | |
5d508e82 FBH |
10122 | local64_set(&hwc->period_left, 0); |
10123 | } else { | |
10124 | period = max_t(u64, 10000, hwc->sample_period); | |
10125 | } | |
3497d206 | 10126 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10127 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10128 | } |
b0a873eb PZ |
10129 | |
10130 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10131 | { |
b0a873eb PZ |
10132 | struct hw_perf_event *hwc = &event->hw; |
10133 | ||
6c7e550f | 10134 | if (is_sampling_event(event)) { |
b0a873eb | 10135 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10136 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10137 | |
10138 | hrtimer_cancel(&hwc->hrtimer); | |
10139 | } | |
24f1e32c FW |
10140 | } |
10141 | ||
ba3dd36c PZ |
10142 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10143 | { | |
10144 | struct hw_perf_event *hwc = &event->hw; | |
10145 | ||
10146 | if (!is_sampling_event(event)) | |
10147 | return; | |
10148 | ||
30f9028b | 10149 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10150 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10151 | ||
10152 | /* | |
10153 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10154 | * mapping and avoid the whole period adjust feedback stuff. | |
10155 | */ | |
10156 | if (event->attr.freq) { | |
10157 | long freq = event->attr.sample_freq; | |
10158 | ||
10159 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10160 | hwc->sample_period = event->attr.sample_period; | |
10161 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10162 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10163 | event->attr.freq = 0; |
10164 | } | |
10165 | } | |
10166 | ||
b0a873eb PZ |
10167 | /* |
10168 | * Software event: cpu wall time clock | |
10169 | */ | |
10170 | ||
10171 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10172 | { |
b0a873eb PZ |
10173 | s64 prev; |
10174 | u64 now; | |
10175 | ||
a4eaf7f1 | 10176 | now = local_clock(); |
b0a873eb PZ |
10177 | prev = local64_xchg(&event->hw.prev_count, now); |
10178 | local64_add(now - prev, &event->count); | |
24f1e32c | 10179 | } |
24f1e32c | 10180 | |
a4eaf7f1 | 10181 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10182 | { |
a4eaf7f1 | 10183 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10184 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10185 | } |
10186 | ||
a4eaf7f1 | 10187 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10188 | { |
b0a873eb PZ |
10189 | perf_swevent_cancel_hrtimer(event); |
10190 | cpu_clock_event_update(event); | |
10191 | } | |
f29ac756 | 10192 | |
a4eaf7f1 PZ |
10193 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10194 | { | |
10195 | if (flags & PERF_EF_START) | |
10196 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10197 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10198 | |
10199 | return 0; | |
10200 | } | |
10201 | ||
10202 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10203 | { | |
10204 | cpu_clock_event_stop(event, flags); | |
10205 | } | |
10206 | ||
b0a873eb PZ |
10207 | static void cpu_clock_event_read(struct perf_event *event) |
10208 | { | |
10209 | cpu_clock_event_update(event); | |
10210 | } | |
f344011c | 10211 | |
b0a873eb PZ |
10212 | static int cpu_clock_event_init(struct perf_event *event) |
10213 | { | |
10214 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10215 | return -ENOENT; | |
10216 | ||
10217 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10218 | return -ENOENT; | |
10219 | ||
2481c5fa SE |
10220 | /* |
10221 | * no branch sampling for software events | |
10222 | */ | |
10223 | if (has_branch_stack(event)) | |
10224 | return -EOPNOTSUPP; | |
10225 | ||
ba3dd36c PZ |
10226 | perf_swevent_init_hrtimer(event); |
10227 | ||
b0a873eb | 10228 | return 0; |
f29ac756 PZ |
10229 | } |
10230 | ||
b0a873eb | 10231 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10232 | .task_ctx_nr = perf_sw_context, |
10233 | ||
34f43927 PZ |
10234 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10235 | ||
b0a873eb | 10236 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10237 | .add = cpu_clock_event_add, |
10238 | .del = cpu_clock_event_del, | |
10239 | .start = cpu_clock_event_start, | |
10240 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10241 | .read = cpu_clock_event_read, |
10242 | }; | |
10243 | ||
10244 | /* | |
10245 | * Software event: task time clock | |
10246 | */ | |
10247 | ||
10248 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10249 | { |
b0a873eb PZ |
10250 | u64 prev; |
10251 | s64 delta; | |
5c92d124 | 10252 | |
b0a873eb PZ |
10253 | prev = local64_xchg(&event->hw.prev_count, now); |
10254 | delta = now - prev; | |
10255 | local64_add(delta, &event->count); | |
10256 | } | |
5c92d124 | 10257 | |
a4eaf7f1 | 10258 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10259 | { |
a4eaf7f1 | 10260 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10261 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10262 | } |
10263 | ||
a4eaf7f1 | 10264 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10265 | { |
10266 | perf_swevent_cancel_hrtimer(event); | |
10267 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10268 | } |
10269 | ||
10270 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10271 | { | |
10272 | if (flags & PERF_EF_START) | |
10273 | task_clock_event_start(event, flags); | |
6a694a60 | 10274 | perf_event_update_userpage(event); |
b0a873eb | 10275 | |
a4eaf7f1 PZ |
10276 | return 0; |
10277 | } | |
10278 | ||
10279 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10280 | { | |
10281 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10282 | } |
10283 | ||
10284 | static void task_clock_event_read(struct perf_event *event) | |
10285 | { | |
768a06e2 PZ |
10286 | u64 now = perf_clock(); |
10287 | u64 delta = now - event->ctx->timestamp; | |
10288 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10289 | |
10290 | task_clock_event_update(event, time); | |
10291 | } | |
10292 | ||
10293 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10294 | { |
b0a873eb PZ |
10295 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10296 | return -ENOENT; | |
10297 | ||
10298 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10299 | return -ENOENT; | |
10300 | ||
2481c5fa SE |
10301 | /* |
10302 | * no branch sampling for software events | |
10303 | */ | |
10304 | if (has_branch_stack(event)) | |
10305 | return -EOPNOTSUPP; | |
10306 | ||
ba3dd36c PZ |
10307 | perf_swevent_init_hrtimer(event); |
10308 | ||
b0a873eb | 10309 | return 0; |
6fb2915d LZ |
10310 | } |
10311 | ||
b0a873eb | 10312 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10313 | .task_ctx_nr = perf_sw_context, |
10314 | ||
34f43927 PZ |
10315 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10316 | ||
b0a873eb | 10317 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10318 | .add = task_clock_event_add, |
10319 | .del = task_clock_event_del, | |
10320 | .start = task_clock_event_start, | |
10321 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10322 | .read = task_clock_event_read, |
10323 | }; | |
6fb2915d | 10324 | |
ad5133b7 | 10325 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10326 | { |
e077df4f | 10327 | } |
6fb2915d | 10328 | |
fbbe0701 SB |
10329 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10330 | { | |
10331 | } | |
10332 | ||
ad5133b7 | 10333 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10334 | { |
ad5133b7 | 10335 | return 0; |
6fb2915d LZ |
10336 | } |
10337 | ||
81ec3f3c JO |
10338 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10339 | { | |
10340 | return 0; | |
10341 | } | |
10342 | ||
18ab2cd3 | 10343 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10344 | |
10345 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10346 | { |
fbbe0701 SB |
10347 | __this_cpu_write(nop_txn_flags, flags); |
10348 | ||
10349 | if (flags & ~PERF_PMU_TXN_ADD) | |
10350 | return; | |
10351 | ||
ad5133b7 | 10352 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10353 | } |
10354 | ||
ad5133b7 PZ |
10355 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10356 | { | |
fbbe0701 SB |
10357 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10358 | ||
10359 | __this_cpu_write(nop_txn_flags, 0); | |
10360 | ||
10361 | if (flags & ~PERF_PMU_TXN_ADD) | |
10362 | return 0; | |
10363 | ||
ad5133b7 PZ |
10364 | perf_pmu_enable(pmu); |
10365 | return 0; | |
10366 | } | |
e077df4f | 10367 | |
ad5133b7 | 10368 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10369 | { |
fbbe0701 SB |
10370 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10371 | ||
10372 | __this_cpu_write(nop_txn_flags, 0); | |
10373 | ||
10374 | if (flags & ~PERF_PMU_TXN_ADD) | |
10375 | return; | |
10376 | ||
ad5133b7 | 10377 | perf_pmu_enable(pmu); |
24f1e32c FW |
10378 | } |
10379 | ||
35edc2a5 PZ |
10380 | static int perf_event_idx_default(struct perf_event *event) |
10381 | { | |
c719f560 | 10382 | return 0; |
35edc2a5 PZ |
10383 | } |
10384 | ||
8dc85d54 PZ |
10385 | /* |
10386 | * Ensures all contexts with the same task_ctx_nr have the same | |
10387 | * pmu_cpu_context too. | |
10388 | */ | |
9e317041 | 10389 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10390 | { |
8dc85d54 | 10391 | struct pmu *pmu; |
b326e956 | 10392 | |
8dc85d54 PZ |
10393 | if (ctxn < 0) |
10394 | return NULL; | |
24f1e32c | 10395 | |
8dc85d54 PZ |
10396 | list_for_each_entry(pmu, &pmus, entry) { |
10397 | if (pmu->task_ctx_nr == ctxn) | |
10398 | return pmu->pmu_cpu_context; | |
10399 | } | |
24f1e32c | 10400 | |
8dc85d54 | 10401 | return NULL; |
24f1e32c FW |
10402 | } |
10403 | ||
51676957 PZ |
10404 | static void free_pmu_context(struct pmu *pmu) |
10405 | { | |
df0062b2 WD |
10406 | /* |
10407 | * Static contexts such as perf_sw_context have a global lifetime | |
10408 | * and may be shared between different PMUs. Avoid freeing them | |
10409 | * when a single PMU is going away. | |
10410 | */ | |
10411 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10412 | return; | |
10413 | ||
51676957 | 10414 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10415 | } |
6e855cd4 AS |
10416 | |
10417 | /* | |
10418 | * Let userspace know that this PMU supports address range filtering: | |
10419 | */ | |
10420 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10421 | struct device_attribute *attr, | |
10422 | char *page) | |
10423 | { | |
10424 | struct pmu *pmu = dev_get_drvdata(dev); | |
10425 | ||
10426 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10427 | } | |
10428 | DEVICE_ATTR_RO(nr_addr_filters); | |
10429 | ||
2e80a82a | 10430 | static struct idr pmu_idr; |
d6d020e9 | 10431 | |
abe43400 PZ |
10432 | static ssize_t |
10433 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10434 | { | |
10435 | struct pmu *pmu = dev_get_drvdata(dev); | |
10436 | ||
10437 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10438 | } | |
90826ca7 | 10439 | static DEVICE_ATTR_RO(type); |
abe43400 | 10440 | |
62b85639 SE |
10441 | static ssize_t |
10442 | perf_event_mux_interval_ms_show(struct device *dev, | |
10443 | struct device_attribute *attr, | |
10444 | char *page) | |
10445 | { | |
10446 | struct pmu *pmu = dev_get_drvdata(dev); | |
10447 | ||
10448 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10449 | } | |
10450 | ||
272325c4 PZ |
10451 | static DEFINE_MUTEX(mux_interval_mutex); |
10452 | ||
62b85639 SE |
10453 | static ssize_t |
10454 | perf_event_mux_interval_ms_store(struct device *dev, | |
10455 | struct device_attribute *attr, | |
10456 | const char *buf, size_t count) | |
10457 | { | |
10458 | struct pmu *pmu = dev_get_drvdata(dev); | |
10459 | int timer, cpu, ret; | |
10460 | ||
10461 | ret = kstrtoint(buf, 0, &timer); | |
10462 | if (ret) | |
10463 | return ret; | |
10464 | ||
10465 | if (timer < 1) | |
10466 | return -EINVAL; | |
10467 | ||
10468 | /* same value, noting to do */ | |
10469 | if (timer == pmu->hrtimer_interval_ms) | |
10470 | return count; | |
10471 | ||
272325c4 | 10472 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10473 | pmu->hrtimer_interval_ms = timer; |
10474 | ||
10475 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10476 | cpus_read_lock(); |
272325c4 | 10477 | for_each_online_cpu(cpu) { |
62b85639 SE |
10478 | struct perf_cpu_context *cpuctx; |
10479 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10480 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10481 | ||
272325c4 PZ |
10482 | cpu_function_call(cpu, |
10483 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10484 | } |
a63fbed7 | 10485 | cpus_read_unlock(); |
272325c4 | 10486 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10487 | |
10488 | return count; | |
10489 | } | |
90826ca7 | 10490 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10491 | |
90826ca7 GKH |
10492 | static struct attribute *pmu_dev_attrs[] = { |
10493 | &dev_attr_type.attr, | |
10494 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10495 | NULL, | |
abe43400 | 10496 | }; |
90826ca7 | 10497 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10498 | |
10499 | static int pmu_bus_running; | |
10500 | static struct bus_type pmu_bus = { | |
10501 | .name = "event_source", | |
90826ca7 | 10502 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10503 | }; |
10504 | ||
10505 | static void pmu_dev_release(struct device *dev) | |
10506 | { | |
10507 | kfree(dev); | |
10508 | } | |
10509 | ||
10510 | static int pmu_dev_alloc(struct pmu *pmu) | |
10511 | { | |
10512 | int ret = -ENOMEM; | |
10513 | ||
10514 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10515 | if (!pmu->dev) | |
10516 | goto out; | |
10517 | ||
0c9d42ed | 10518 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10519 | device_initialize(pmu->dev); |
10520 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10521 | if (ret) | |
10522 | goto free_dev; | |
10523 | ||
10524 | dev_set_drvdata(pmu->dev, pmu); | |
10525 | pmu->dev->bus = &pmu_bus; | |
10526 | pmu->dev->release = pmu_dev_release; | |
10527 | ret = device_add(pmu->dev); | |
10528 | if (ret) | |
10529 | goto free_dev; | |
10530 | ||
6e855cd4 AS |
10531 | /* For PMUs with address filters, throw in an extra attribute: */ |
10532 | if (pmu->nr_addr_filters) | |
10533 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10534 | ||
10535 | if (ret) | |
10536 | goto del_dev; | |
10537 | ||
f3a3a825 JO |
10538 | if (pmu->attr_update) |
10539 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10540 | ||
10541 | if (ret) | |
10542 | goto del_dev; | |
10543 | ||
abe43400 PZ |
10544 | out: |
10545 | return ret; | |
10546 | ||
6e855cd4 AS |
10547 | del_dev: |
10548 | device_del(pmu->dev); | |
10549 | ||
abe43400 PZ |
10550 | free_dev: |
10551 | put_device(pmu->dev); | |
10552 | goto out; | |
10553 | } | |
10554 | ||
547e9fd7 | 10555 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10556 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10557 | |
03d8e80b | 10558 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10559 | { |
66d258c5 | 10560 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10561 | |
b0a873eb | 10562 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10563 | ret = -ENOMEM; |
10564 | pmu->pmu_disable_count = alloc_percpu(int); | |
10565 | if (!pmu->pmu_disable_count) | |
10566 | goto unlock; | |
f29ac756 | 10567 | |
2e80a82a PZ |
10568 | pmu->type = -1; |
10569 | if (!name) | |
10570 | goto skip_type; | |
10571 | pmu->name = name; | |
10572 | ||
66d258c5 PZ |
10573 | if (type != PERF_TYPE_SOFTWARE) { |
10574 | if (type >= 0) | |
10575 | max = type; | |
10576 | ||
10577 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10578 | if (ret < 0) | |
2e80a82a | 10579 | goto free_pdc; |
66d258c5 PZ |
10580 | |
10581 | WARN_ON(type >= 0 && ret != type); | |
10582 | ||
10583 | type = ret; | |
2e80a82a PZ |
10584 | } |
10585 | pmu->type = type; | |
10586 | ||
abe43400 PZ |
10587 | if (pmu_bus_running) { |
10588 | ret = pmu_dev_alloc(pmu); | |
10589 | if (ret) | |
10590 | goto free_idr; | |
10591 | } | |
10592 | ||
2e80a82a | 10593 | skip_type: |
26657848 PZ |
10594 | if (pmu->task_ctx_nr == perf_hw_context) { |
10595 | static int hw_context_taken = 0; | |
10596 | ||
5101ef20 MR |
10597 | /* |
10598 | * Other than systems with heterogeneous CPUs, it never makes | |
10599 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10600 | * uncore must use perf_invalid_context. | |
10601 | */ | |
10602 | if (WARN_ON_ONCE(hw_context_taken && | |
10603 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10604 | pmu->task_ctx_nr = perf_invalid_context; |
10605 | ||
10606 | hw_context_taken = 1; | |
10607 | } | |
10608 | ||
8dc85d54 PZ |
10609 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10610 | if (pmu->pmu_cpu_context) | |
10611 | goto got_cpu_context; | |
f29ac756 | 10612 | |
c4814202 | 10613 | ret = -ENOMEM; |
108b02cf PZ |
10614 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10615 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10616 | goto free_dev; |
f344011c | 10617 | |
108b02cf PZ |
10618 | for_each_possible_cpu(cpu) { |
10619 | struct perf_cpu_context *cpuctx; | |
10620 | ||
10621 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10622 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10623 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10624 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10625 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10626 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10627 | |
272325c4 | 10628 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
10629 | |
10630 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
10631 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 10632 | } |
76e1d904 | 10633 | |
8dc85d54 | 10634 | got_cpu_context: |
ad5133b7 PZ |
10635 | if (!pmu->start_txn) { |
10636 | if (pmu->pmu_enable) { | |
10637 | /* | |
10638 | * If we have pmu_enable/pmu_disable calls, install | |
10639 | * transaction stubs that use that to try and batch | |
10640 | * hardware accesses. | |
10641 | */ | |
10642 | pmu->start_txn = perf_pmu_start_txn; | |
10643 | pmu->commit_txn = perf_pmu_commit_txn; | |
10644 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10645 | } else { | |
fbbe0701 | 10646 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10647 | pmu->commit_txn = perf_pmu_nop_int; |
10648 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10649 | } |
5c92d124 | 10650 | } |
15dbf27c | 10651 | |
ad5133b7 PZ |
10652 | if (!pmu->pmu_enable) { |
10653 | pmu->pmu_enable = perf_pmu_nop_void; | |
10654 | pmu->pmu_disable = perf_pmu_nop_void; | |
10655 | } | |
10656 | ||
81ec3f3c JO |
10657 | if (!pmu->check_period) |
10658 | pmu->check_period = perf_event_nop_int; | |
10659 | ||
35edc2a5 PZ |
10660 | if (!pmu->event_idx) |
10661 | pmu->event_idx = perf_event_idx_default; | |
10662 | ||
d44f821b LK |
10663 | /* |
10664 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10665 | * since these cannot be in the IDR. This way the linear search | |
10666 | * is fast, provided a valid software event is provided. | |
10667 | */ | |
10668 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10669 | list_add_rcu(&pmu->entry, &pmus); | |
10670 | else | |
10671 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10672 | ||
bed5b25a | 10673 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10674 | ret = 0; |
10675 | unlock: | |
b0a873eb PZ |
10676 | mutex_unlock(&pmus_lock); |
10677 | ||
33696fc0 | 10678 | return ret; |
108b02cf | 10679 | |
abe43400 PZ |
10680 | free_dev: |
10681 | device_del(pmu->dev); | |
10682 | put_device(pmu->dev); | |
10683 | ||
2e80a82a | 10684 | free_idr: |
66d258c5 | 10685 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10686 | idr_remove(&pmu_idr, pmu->type); |
10687 | ||
108b02cf PZ |
10688 | free_pdc: |
10689 | free_percpu(pmu->pmu_disable_count); | |
10690 | goto unlock; | |
f29ac756 | 10691 | } |
c464c76e | 10692 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10693 | |
b0a873eb | 10694 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10695 | { |
b0a873eb PZ |
10696 | mutex_lock(&pmus_lock); |
10697 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10698 | |
0475f9ea | 10699 | /* |
cde8e884 PZ |
10700 | * We dereference the pmu list under both SRCU and regular RCU, so |
10701 | * synchronize against both of those. | |
0475f9ea | 10702 | */ |
b0a873eb | 10703 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10704 | synchronize_rcu(); |
d6d020e9 | 10705 | |
33696fc0 | 10706 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10707 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10708 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10709 | if (pmu_bus_running) { |
0933840a JO |
10710 | if (pmu->nr_addr_filters) |
10711 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10712 | device_del(pmu->dev); | |
10713 | put_device(pmu->dev); | |
10714 | } | |
51676957 | 10715 | free_pmu_context(pmu); |
a9f97721 | 10716 | mutex_unlock(&pmus_lock); |
b0a873eb | 10717 | } |
c464c76e | 10718 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10719 | |
e321d02d KL |
10720 | static inline bool has_extended_regs(struct perf_event *event) |
10721 | { | |
10722 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10723 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10724 | } | |
10725 | ||
cc34b98b MR |
10726 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10727 | { | |
ccd41c86 | 10728 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10729 | int ret; |
10730 | ||
10731 | if (!try_module_get(pmu->module)) | |
10732 | return -ENODEV; | |
ccd41c86 | 10733 | |
0c7296ca PZ |
10734 | /* |
10735 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10736 | * for example, validate if the group fits on the PMU. Therefore, | |
10737 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10738 | * the sibling_list. | |
10739 | */ | |
10740 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10741 | /* |
10742 | * This ctx->mutex can nest when we're called through | |
10743 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10744 | */ | |
10745 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10746 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10747 | BUG_ON(!ctx); |
10748 | } | |
10749 | ||
cc34b98b MR |
10750 | event->pmu = pmu; |
10751 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10752 | |
10753 | if (ctx) | |
10754 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10755 | ||
cc6795ae | 10756 | if (!ret) { |
e321d02d KL |
10757 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10758 | has_extended_regs(event)) | |
10759 | ret = -EOPNOTSUPP; | |
10760 | ||
cc6795ae | 10761 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10762 | event_has_any_exclude_flag(event)) |
cc6795ae | 10763 | ret = -EINVAL; |
e321d02d KL |
10764 | |
10765 | if (ret && event->destroy) | |
10766 | event->destroy(event); | |
cc6795ae AM |
10767 | } |
10768 | ||
cc34b98b MR |
10769 | if (ret) |
10770 | module_put(pmu->module); | |
10771 | ||
10772 | return ret; | |
10773 | } | |
10774 | ||
18ab2cd3 | 10775 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10776 | { |
66d258c5 | 10777 | int idx, type, ret; |
85c617ab | 10778 | struct pmu *pmu; |
b0a873eb PZ |
10779 | |
10780 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10781 | |
40999312 KL |
10782 | /* Try parent's PMU first: */ |
10783 | if (event->parent && event->parent->pmu) { | |
10784 | pmu = event->parent->pmu; | |
10785 | ret = perf_try_init_event(pmu, event); | |
10786 | if (!ret) | |
10787 | goto unlock; | |
10788 | } | |
10789 | ||
66d258c5 PZ |
10790 | /* |
10791 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
10792 | * are often aliases for PERF_TYPE_RAW. | |
10793 | */ | |
10794 | type = event->attr.type; | |
10795 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
10796 | type = PERF_TYPE_RAW; | |
10797 | ||
10798 | again: | |
2e80a82a | 10799 | rcu_read_lock(); |
66d258c5 | 10800 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 10801 | rcu_read_unlock(); |
940c5b29 | 10802 | if (pmu) { |
cc34b98b | 10803 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
10804 | if (ret == -ENOENT && event->attr.type != type) { |
10805 | type = event->attr.type; | |
10806 | goto again; | |
10807 | } | |
10808 | ||
940c5b29 LM |
10809 | if (ret) |
10810 | pmu = ERR_PTR(ret); | |
66d258c5 | 10811 | |
2e80a82a | 10812 | goto unlock; |
940c5b29 | 10813 | } |
2e80a82a | 10814 | |
9f0bff11 | 10815 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 10816 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10817 | if (!ret) |
e5f4d339 | 10818 | goto unlock; |
76e1d904 | 10819 | |
b0a873eb PZ |
10820 | if (ret != -ENOENT) { |
10821 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10822 | goto unlock; |
f344011c | 10823 | } |
5c92d124 | 10824 | } |
e5f4d339 PZ |
10825 | pmu = ERR_PTR(-ENOENT); |
10826 | unlock: | |
b0a873eb | 10827 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10828 | |
4aeb0b42 | 10829 | return pmu; |
5c92d124 IM |
10830 | } |
10831 | ||
f2fb6bef KL |
10832 | static void attach_sb_event(struct perf_event *event) |
10833 | { | |
10834 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10835 | ||
10836 | raw_spin_lock(&pel->lock); | |
10837 | list_add_rcu(&event->sb_list, &pel->list); | |
10838 | raw_spin_unlock(&pel->lock); | |
10839 | } | |
10840 | ||
aab5b71e PZ |
10841 | /* |
10842 | * We keep a list of all !task (and therefore per-cpu) events | |
10843 | * that need to receive side-band records. | |
10844 | * | |
10845 | * This avoids having to scan all the various PMU per-cpu contexts | |
10846 | * looking for them. | |
10847 | */ | |
f2fb6bef KL |
10848 | static void account_pmu_sb_event(struct perf_event *event) |
10849 | { | |
a4f144eb | 10850 | if (is_sb_event(event)) |
f2fb6bef KL |
10851 | attach_sb_event(event); |
10852 | } | |
10853 | ||
4beb31f3 FW |
10854 | static void account_event_cpu(struct perf_event *event, int cpu) |
10855 | { | |
10856 | if (event->parent) | |
10857 | return; | |
10858 | ||
4beb31f3 FW |
10859 | if (is_cgroup_event(event)) |
10860 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10861 | } | |
10862 | ||
555e0c1e FW |
10863 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10864 | static void account_freq_event_nohz(void) | |
10865 | { | |
10866 | #ifdef CONFIG_NO_HZ_FULL | |
10867 | /* Lock so we don't race with concurrent unaccount */ | |
10868 | spin_lock(&nr_freq_lock); | |
10869 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10870 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10871 | spin_unlock(&nr_freq_lock); | |
10872 | #endif | |
10873 | } | |
10874 | ||
10875 | static void account_freq_event(void) | |
10876 | { | |
10877 | if (tick_nohz_full_enabled()) | |
10878 | account_freq_event_nohz(); | |
10879 | else | |
10880 | atomic_inc(&nr_freq_events); | |
10881 | } | |
10882 | ||
10883 | ||
766d6c07 FW |
10884 | static void account_event(struct perf_event *event) |
10885 | { | |
25432ae9 PZ |
10886 | bool inc = false; |
10887 | ||
4beb31f3 FW |
10888 | if (event->parent) |
10889 | return; | |
10890 | ||
766d6c07 | 10891 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10892 | inc = true; |
766d6c07 FW |
10893 | if (event->attr.mmap || event->attr.mmap_data) |
10894 | atomic_inc(&nr_mmap_events); | |
10895 | if (event->attr.comm) | |
10896 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10897 | if (event->attr.namespaces) |
10898 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
10899 | if (event->attr.cgroup) |
10900 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
10901 | if (event->attr.task) |
10902 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10903 | if (event->attr.freq) |
10904 | account_freq_event(); | |
45ac1403 AH |
10905 | if (event->attr.context_switch) { |
10906 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10907 | inc = true; |
45ac1403 | 10908 | } |
4beb31f3 | 10909 | if (has_branch_stack(event)) |
25432ae9 | 10910 | inc = true; |
4beb31f3 | 10911 | if (is_cgroup_event(event)) |
25432ae9 | 10912 | inc = true; |
76193a94 SL |
10913 | if (event->attr.ksymbol) |
10914 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10915 | if (event->attr.bpf_event) |
10916 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10917 | |
9107c89e | 10918 | if (inc) { |
5bce9db1 AS |
10919 | /* |
10920 | * We need the mutex here because static_branch_enable() | |
10921 | * must complete *before* the perf_sched_count increment | |
10922 | * becomes visible. | |
10923 | */ | |
9107c89e PZ |
10924 | if (atomic_inc_not_zero(&perf_sched_count)) |
10925 | goto enabled; | |
10926 | ||
10927 | mutex_lock(&perf_sched_mutex); | |
10928 | if (!atomic_read(&perf_sched_count)) { | |
10929 | static_branch_enable(&perf_sched_events); | |
10930 | /* | |
10931 | * Guarantee that all CPUs observe they key change and | |
10932 | * call the perf scheduling hooks before proceeding to | |
10933 | * install events that need them. | |
10934 | */ | |
0809d954 | 10935 | synchronize_rcu(); |
9107c89e PZ |
10936 | } |
10937 | /* | |
10938 | * Now that we have waited for the sync_sched(), allow further | |
10939 | * increments to by-pass the mutex. | |
10940 | */ | |
10941 | atomic_inc(&perf_sched_count); | |
10942 | mutex_unlock(&perf_sched_mutex); | |
10943 | } | |
10944 | enabled: | |
4beb31f3 FW |
10945 | |
10946 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10947 | |
10948 | account_pmu_sb_event(event); | |
766d6c07 FW |
10949 | } |
10950 | ||
0793a61d | 10951 | /* |
788faab7 | 10952 | * Allocate and initialize an event structure |
0793a61d | 10953 | */ |
cdd6c482 | 10954 | static struct perf_event * |
c3f00c70 | 10955 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10956 | struct task_struct *task, |
10957 | struct perf_event *group_leader, | |
10958 | struct perf_event *parent_event, | |
4dc0da86 | 10959 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10960 | void *context, int cgroup_fd) |
0793a61d | 10961 | { |
51b0fe39 | 10962 | struct pmu *pmu; |
cdd6c482 IM |
10963 | struct perf_event *event; |
10964 | struct hw_perf_event *hwc; | |
90983b16 | 10965 | long err = -EINVAL; |
0793a61d | 10966 | |
66832eb4 ON |
10967 | if ((unsigned)cpu >= nr_cpu_ids) { |
10968 | if (!task || cpu != -1) | |
10969 | return ERR_PTR(-EINVAL); | |
10970 | } | |
10971 | ||
c3f00c70 | 10972 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10973 | if (!event) |
d5d2bc0d | 10974 | return ERR_PTR(-ENOMEM); |
0793a61d | 10975 | |
04289bb9 | 10976 | /* |
cdd6c482 | 10977 | * Single events are their own group leaders, with an |
04289bb9 IM |
10978 | * empty sibling list: |
10979 | */ | |
10980 | if (!group_leader) | |
cdd6c482 | 10981 | group_leader = event; |
04289bb9 | 10982 | |
cdd6c482 IM |
10983 | mutex_init(&event->child_mutex); |
10984 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10985 | |
cdd6c482 IM |
10986 | INIT_LIST_HEAD(&event->event_entry); |
10987 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10988 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10989 | init_event_group(event); |
10c6db11 | 10990 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10991 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10992 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10993 | INIT_HLIST_NODE(&event->hlist_entry); |
10994 | ||
10c6db11 | 10995 | |
cdd6c482 | 10996 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10997 | event->pending_disable = -1; |
e360adbe | 10998 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10999 | |
cdd6c482 | 11000 | mutex_init(&event->mmap_mutex); |
375637bc | 11001 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11002 | |
a6fa941d | 11003 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11004 | event->cpu = cpu; |
11005 | event->attr = *attr; | |
11006 | event->group_leader = group_leader; | |
11007 | event->pmu = NULL; | |
cdd6c482 | 11008 | event->oncpu = -1; |
a96bbc16 | 11009 | |
cdd6c482 | 11010 | event->parent = parent_event; |
b84fbc9f | 11011 | |
17cf22c3 | 11012 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11013 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11014 | |
cdd6c482 | 11015 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11016 | |
d580ff86 PZ |
11017 | if (task) { |
11018 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11019 | /* |
50f16a8b PZ |
11020 | * XXX pmu::event_init needs to know what task to account to |
11021 | * and we cannot use the ctx information because we need the | |
11022 | * pmu before we get a ctx. | |
d580ff86 | 11023 | */ |
7b3c92b8 | 11024 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11025 | } |
11026 | ||
34f43927 PZ |
11027 | event->clock = &local_clock; |
11028 | if (parent_event) | |
11029 | event->clock = parent_event->clock; | |
11030 | ||
4dc0da86 | 11031 | if (!overflow_handler && parent_event) { |
b326e956 | 11032 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11033 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11034 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11035 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11036 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11037 | |
85192dbf | 11038 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11039 | event->prog = prog; |
11040 | event->orig_overflow_handler = | |
11041 | parent_event->orig_overflow_handler; | |
11042 | } | |
11043 | #endif | |
4dc0da86 | 11044 | } |
66832eb4 | 11045 | |
1879445d WN |
11046 | if (overflow_handler) { |
11047 | event->overflow_handler = overflow_handler; | |
11048 | event->overflow_handler_context = context; | |
9ecda41a WN |
11049 | } else if (is_write_backward(event)){ |
11050 | event->overflow_handler = perf_event_output_backward; | |
11051 | event->overflow_handler_context = NULL; | |
1879445d | 11052 | } else { |
9ecda41a | 11053 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11054 | event->overflow_handler_context = NULL; |
11055 | } | |
97eaf530 | 11056 | |
0231bb53 | 11057 | perf_event__state_init(event); |
a86ed508 | 11058 | |
4aeb0b42 | 11059 | pmu = NULL; |
b8e83514 | 11060 | |
cdd6c482 | 11061 | hwc = &event->hw; |
bd2b5b12 | 11062 | hwc->sample_period = attr->sample_period; |
0d48696f | 11063 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11064 | hwc->sample_period = 1; |
eced1dfc | 11065 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11066 | |
e7850595 | 11067 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11068 | |
2023b359 | 11069 | /* |
ba5213ae PZ |
11070 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11071 | * See perf_output_read(). | |
2023b359 | 11072 | */ |
ba5213ae | 11073 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11074 | goto err_ns; |
a46a2300 YZ |
11075 | |
11076 | if (!has_branch_stack(event)) | |
11077 | event->attr.branch_sample_type = 0; | |
2023b359 | 11078 | |
b0a873eb | 11079 | pmu = perf_init_event(event); |
85c617ab | 11080 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11081 | err = PTR_ERR(pmu); |
90983b16 | 11082 | goto err_ns; |
621a01ea | 11083 | } |
d5d2bc0d | 11084 | |
09f4e8f0 PZ |
11085 | /* |
11086 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11087 | * be different on other CPUs in the uncore mask. | |
11088 | */ | |
11089 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11090 | err = -EINVAL; | |
11091 | goto err_pmu; | |
11092 | } | |
11093 | ||
ab43762e AS |
11094 | if (event->attr.aux_output && |
11095 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11096 | err = -EOPNOTSUPP; | |
11097 | goto err_pmu; | |
11098 | } | |
11099 | ||
98add2af PZ |
11100 | if (cgroup_fd != -1) { |
11101 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11102 | if (err) | |
11103 | goto err_pmu; | |
11104 | } | |
11105 | ||
bed5b25a AS |
11106 | err = exclusive_event_init(event); |
11107 | if (err) | |
11108 | goto err_pmu; | |
11109 | ||
375637bc | 11110 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11111 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11112 | sizeof(struct perf_addr_filter_range), | |
11113 | GFP_KERNEL); | |
11114 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11115 | err = -ENOMEM; |
375637bc | 11116 | goto err_per_task; |
36cc2b92 | 11117 | } |
375637bc | 11118 | |
18736eef AS |
11119 | /* |
11120 | * Clone the parent's vma offsets: they are valid until exec() | |
11121 | * even if the mm is not shared with the parent. | |
11122 | */ | |
11123 | if (event->parent) { | |
11124 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11125 | ||
11126 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11127 | memcpy(event->addr_filter_ranges, |
11128 | event->parent->addr_filter_ranges, | |
11129 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11130 | raw_spin_unlock_irq(&ifh->lock); |
11131 | } | |
11132 | ||
375637bc AS |
11133 | /* force hw sync on the address filters */ |
11134 | event->addr_filters_gen = 1; | |
11135 | } | |
11136 | ||
cdd6c482 | 11137 | if (!event->parent) { |
927c7a9e | 11138 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11139 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11140 | if (err) |
375637bc | 11141 | goto err_addr_filters; |
d010b332 | 11142 | } |
f344011c | 11143 | } |
9ee318a7 | 11144 | |
da97e184 JFG |
11145 | err = security_perf_event_alloc(event); |
11146 | if (err) | |
11147 | goto err_callchain_buffer; | |
11148 | ||
927a5570 AS |
11149 | /* symmetric to unaccount_event() in _free_event() */ |
11150 | account_event(event); | |
11151 | ||
cdd6c482 | 11152 | return event; |
90983b16 | 11153 | |
da97e184 JFG |
11154 | err_callchain_buffer: |
11155 | if (!event->parent) { | |
11156 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11157 | put_callchain_buffers(); | |
11158 | } | |
375637bc | 11159 | err_addr_filters: |
c60f83b8 | 11160 | kfree(event->addr_filter_ranges); |
375637bc | 11161 | |
bed5b25a AS |
11162 | err_per_task: |
11163 | exclusive_event_destroy(event); | |
11164 | ||
90983b16 | 11165 | err_pmu: |
98add2af PZ |
11166 | if (is_cgroup_event(event)) |
11167 | perf_detach_cgroup(event); | |
90983b16 FW |
11168 | if (event->destroy) |
11169 | event->destroy(event); | |
c464c76e | 11170 | module_put(pmu->module); |
90983b16 FW |
11171 | err_ns: |
11172 | if (event->ns) | |
11173 | put_pid_ns(event->ns); | |
621b6d2e PB |
11174 | if (event->hw.target) |
11175 | put_task_struct(event->hw.target); | |
90983b16 FW |
11176 | kfree(event); |
11177 | ||
11178 | return ERR_PTR(err); | |
0793a61d TG |
11179 | } |
11180 | ||
cdd6c482 IM |
11181 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11182 | struct perf_event_attr *attr) | |
974802ea | 11183 | { |
974802ea | 11184 | u32 size; |
cdf8073d | 11185 | int ret; |
974802ea | 11186 | |
c2ba8f41 | 11187 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11188 | memset(attr, 0, sizeof(*attr)); |
11189 | ||
11190 | ret = get_user(size, &uattr->size); | |
11191 | if (ret) | |
11192 | return ret; | |
11193 | ||
c2ba8f41 AS |
11194 | /* ABI compatibility quirk: */ |
11195 | if (!size) | |
974802ea | 11196 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11197 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11198 | goto err_size; |
11199 | ||
c2ba8f41 AS |
11200 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11201 | if (ret) { | |
11202 | if (ret == -E2BIG) | |
11203 | goto err_size; | |
11204 | return ret; | |
974802ea PZ |
11205 | } |
11206 | ||
f12f42ac MX |
11207 | attr->size = size; |
11208 | ||
a4faf00d | 11209 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11210 | return -EINVAL; |
11211 | ||
11212 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11213 | return -EINVAL; | |
11214 | ||
11215 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11216 | return -EINVAL; | |
11217 | ||
bce38cd5 SE |
11218 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11219 | u64 mask = attr->branch_sample_type; | |
11220 | ||
11221 | /* only using defined bits */ | |
11222 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11223 | return -EINVAL; | |
11224 | ||
11225 | /* at least one branch bit must be set */ | |
11226 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11227 | return -EINVAL; | |
11228 | ||
bce38cd5 SE |
11229 | /* propagate priv level, when not set for branch */ |
11230 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11231 | ||
11232 | /* exclude_kernel checked on syscall entry */ | |
11233 | if (!attr->exclude_kernel) | |
11234 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11235 | ||
11236 | if (!attr->exclude_user) | |
11237 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11238 | ||
11239 | if (!attr->exclude_hv) | |
11240 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11241 | /* | |
11242 | * adjust user setting (for HW filter setup) | |
11243 | */ | |
11244 | attr->branch_sample_type = mask; | |
11245 | } | |
e712209a | 11246 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11247 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11248 | ret = perf_allow_kernel(attr); | |
11249 | if (ret) | |
11250 | return ret; | |
11251 | } | |
bce38cd5 | 11252 | } |
4018994f | 11253 | |
c5ebcedb | 11254 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11255 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11256 | if (ret) |
11257 | return ret; | |
11258 | } | |
11259 | ||
11260 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11261 | if (!arch_perf_have_user_stack_dump()) | |
11262 | return -ENOSYS; | |
11263 | ||
11264 | /* | |
11265 | * We have __u32 type for the size, but so far | |
11266 | * we can only use __u16 as maximum due to the | |
11267 | * __u16 sample size limit. | |
11268 | */ | |
11269 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11270 | return -EINVAL; |
c5ebcedb | 11271 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11272 | return -EINVAL; |
c5ebcedb | 11273 | } |
4018994f | 11274 | |
5f970521 JO |
11275 | if (!attr->sample_max_stack) |
11276 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11277 | ||
60e2364e SE |
11278 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11279 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11280 | |
11281 | #ifndef CONFIG_CGROUP_PERF | |
11282 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11283 | return -EINVAL; | |
11284 | #endif | |
11285 | ||
974802ea PZ |
11286 | out: |
11287 | return ret; | |
11288 | ||
11289 | err_size: | |
11290 | put_user(sizeof(*attr), &uattr->size); | |
11291 | ret = -E2BIG; | |
11292 | goto out; | |
11293 | } | |
11294 | ||
ac9721f3 PZ |
11295 | static int |
11296 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11297 | { |
56de4e8f | 11298 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11299 | int ret = -EINVAL; |
11300 | ||
ac9721f3 | 11301 | if (!output_event) |
a4be7c27 PZ |
11302 | goto set; |
11303 | ||
ac9721f3 PZ |
11304 | /* don't allow circular references */ |
11305 | if (event == output_event) | |
a4be7c27 PZ |
11306 | goto out; |
11307 | ||
0f139300 PZ |
11308 | /* |
11309 | * Don't allow cross-cpu buffers | |
11310 | */ | |
11311 | if (output_event->cpu != event->cpu) | |
11312 | goto out; | |
11313 | ||
11314 | /* | |
76369139 | 11315 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11316 | */ |
11317 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11318 | goto out; | |
11319 | ||
34f43927 PZ |
11320 | /* |
11321 | * Mixing clocks in the same buffer is trouble you don't need. | |
11322 | */ | |
11323 | if (output_event->clock != event->clock) | |
11324 | goto out; | |
11325 | ||
9ecda41a WN |
11326 | /* |
11327 | * Either writing ring buffer from beginning or from end. | |
11328 | * Mixing is not allowed. | |
11329 | */ | |
11330 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11331 | goto out; | |
11332 | ||
45bfb2e5 PZ |
11333 | /* |
11334 | * If both events generate aux data, they must be on the same PMU | |
11335 | */ | |
11336 | if (has_aux(event) && has_aux(output_event) && | |
11337 | event->pmu != output_event->pmu) | |
11338 | goto out; | |
11339 | ||
a4be7c27 | 11340 | set: |
cdd6c482 | 11341 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11342 | /* Can't redirect output if we've got an active mmap() */ |
11343 | if (atomic_read(&event->mmap_count)) | |
11344 | goto unlock; | |
a4be7c27 | 11345 | |
ac9721f3 | 11346 | if (output_event) { |
76369139 FW |
11347 | /* get the rb we want to redirect to */ |
11348 | rb = ring_buffer_get(output_event); | |
11349 | if (!rb) | |
ac9721f3 | 11350 | goto unlock; |
a4be7c27 PZ |
11351 | } |
11352 | ||
b69cf536 | 11353 | ring_buffer_attach(event, rb); |
9bb5d40c | 11354 | |
a4be7c27 | 11355 | ret = 0; |
ac9721f3 PZ |
11356 | unlock: |
11357 | mutex_unlock(&event->mmap_mutex); | |
11358 | ||
a4be7c27 | 11359 | out: |
a4be7c27 PZ |
11360 | return ret; |
11361 | } | |
11362 | ||
f63a8daa PZ |
11363 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11364 | { | |
11365 | if (b < a) | |
11366 | swap(a, b); | |
11367 | ||
11368 | mutex_lock(a); | |
11369 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11370 | } | |
11371 | ||
34f43927 PZ |
11372 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11373 | { | |
11374 | bool nmi_safe = false; | |
11375 | ||
11376 | switch (clk_id) { | |
11377 | case CLOCK_MONOTONIC: | |
11378 | event->clock = &ktime_get_mono_fast_ns; | |
11379 | nmi_safe = true; | |
11380 | break; | |
11381 | ||
11382 | case CLOCK_MONOTONIC_RAW: | |
11383 | event->clock = &ktime_get_raw_fast_ns; | |
11384 | nmi_safe = true; | |
11385 | break; | |
11386 | ||
11387 | case CLOCK_REALTIME: | |
11388 | event->clock = &ktime_get_real_ns; | |
11389 | break; | |
11390 | ||
11391 | case CLOCK_BOOTTIME: | |
9285ec4c | 11392 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11393 | break; |
11394 | ||
11395 | case CLOCK_TAI: | |
9285ec4c | 11396 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11397 | break; |
11398 | ||
11399 | default: | |
11400 | return -EINVAL; | |
11401 | } | |
11402 | ||
11403 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11404 | return -EINVAL; | |
11405 | ||
11406 | return 0; | |
11407 | } | |
11408 | ||
321027c1 PZ |
11409 | /* |
11410 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11411 | * mutexes. | |
11412 | */ | |
11413 | static struct perf_event_context * | |
11414 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11415 | struct perf_event_context *ctx) | |
11416 | { | |
11417 | struct perf_event_context *gctx; | |
11418 | ||
11419 | again: | |
11420 | rcu_read_lock(); | |
11421 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11422 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11423 | rcu_read_unlock(); |
11424 | goto again; | |
11425 | } | |
11426 | rcu_read_unlock(); | |
11427 | ||
11428 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11429 | ||
11430 | if (group_leader->ctx != gctx) { | |
11431 | mutex_unlock(&ctx->mutex); | |
11432 | mutex_unlock(&gctx->mutex); | |
11433 | put_ctx(gctx); | |
11434 | goto again; | |
11435 | } | |
11436 | ||
11437 | return gctx; | |
11438 | } | |
11439 | ||
0793a61d | 11440 | /** |
cdd6c482 | 11441 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11442 | * |
cdd6c482 | 11443 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11444 | * @pid: target pid |
9f66a381 | 11445 | * @cpu: target cpu |
cdd6c482 | 11446 | * @group_fd: group leader event fd |
0793a61d | 11447 | */ |
cdd6c482 IM |
11448 | SYSCALL_DEFINE5(perf_event_open, |
11449 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11450 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11451 | { |
b04243ef PZ |
11452 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11453 | struct perf_event *event, *sibling; | |
cdd6c482 | 11454 | struct perf_event_attr attr; |
f63a8daa | 11455 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 11456 | struct file *event_file = NULL; |
2903ff01 | 11457 | struct fd group = {NULL, 0}; |
38a81da2 | 11458 | struct task_struct *task = NULL; |
89a1e187 | 11459 | struct pmu *pmu; |
ea635c64 | 11460 | int event_fd; |
b04243ef | 11461 | int move_group = 0; |
dc86cabe | 11462 | int err; |
a21b0b35 | 11463 | int f_flags = O_RDWR; |
79dff51e | 11464 | int cgroup_fd = -1; |
0793a61d | 11465 | |
2743a5b0 | 11466 | /* for future expandability... */ |
e5d1367f | 11467 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11468 | return -EINVAL; |
11469 | ||
da97e184 JFG |
11470 | /* Do we allow access to perf_event_open(2) ? */ |
11471 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11472 | if (err) | |
11473 | return err; | |
11474 | ||
dc86cabe IM |
11475 | err = perf_copy_attr(attr_uptr, &attr); |
11476 | if (err) | |
11477 | return err; | |
eab656ae | 11478 | |
0764771d | 11479 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11480 | err = perf_allow_kernel(&attr); |
11481 | if (err) | |
11482 | return err; | |
0764771d PZ |
11483 | } |
11484 | ||
e4222673 HB |
11485 | if (attr.namespaces) { |
11486 | if (!capable(CAP_SYS_ADMIN)) | |
11487 | return -EACCES; | |
11488 | } | |
11489 | ||
df58ab24 | 11490 | if (attr.freq) { |
cdd6c482 | 11491 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11492 | return -EINVAL; |
0819b2e3 PZ |
11493 | } else { |
11494 | if (attr.sample_period & (1ULL << 63)) | |
11495 | return -EINVAL; | |
df58ab24 PZ |
11496 | } |
11497 | ||
fc7ce9c7 | 11498 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11499 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11500 | err = perf_allow_kernel(&attr); | |
11501 | if (err) | |
11502 | return err; | |
11503 | } | |
fc7ce9c7 | 11504 | |
b0c8fdc7 DH |
11505 | err = security_locked_down(LOCKDOWN_PERF); |
11506 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11507 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11508 | return err; | |
11509 | ||
11510 | err = 0; | |
11511 | ||
e5d1367f SE |
11512 | /* |
11513 | * In cgroup mode, the pid argument is used to pass the fd | |
11514 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11515 | * designates the cpu on which to monitor threads from that | |
11516 | * cgroup. | |
11517 | */ | |
11518 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11519 | return -EINVAL; | |
11520 | ||
a21b0b35 YD |
11521 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11522 | f_flags |= O_CLOEXEC; | |
11523 | ||
11524 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11525 | if (event_fd < 0) |
11526 | return event_fd; | |
11527 | ||
ac9721f3 | 11528 | if (group_fd != -1) { |
2903ff01 AV |
11529 | err = perf_fget_light(group_fd, &group); |
11530 | if (err) | |
d14b12d7 | 11531 | goto err_fd; |
2903ff01 | 11532 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11533 | if (flags & PERF_FLAG_FD_OUTPUT) |
11534 | output_event = group_leader; | |
11535 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11536 | group_leader = NULL; | |
11537 | } | |
11538 | ||
e5d1367f | 11539 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11540 | task = find_lively_task_by_vpid(pid); |
11541 | if (IS_ERR(task)) { | |
11542 | err = PTR_ERR(task); | |
11543 | goto err_group_fd; | |
11544 | } | |
11545 | } | |
11546 | ||
1f4ee503 PZ |
11547 | if (task && group_leader && |
11548 | group_leader->attr.inherit != attr.inherit) { | |
11549 | err = -EINVAL; | |
11550 | goto err_task; | |
11551 | } | |
11552 | ||
79c9ce57 | 11553 | if (task) { |
69143038 | 11554 | err = mutex_lock_interruptible(&task->signal->exec_update_mutex); |
79c9ce57 | 11555 | if (err) |
e5aeee51 | 11556 | goto err_task; |
79c9ce57 PZ |
11557 | |
11558 | /* | |
11559 | * Reuse ptrace permission checks for now. | |
11560 | * | |
69143038 | 11561 | * We must hold exec_update_mutex across this and any potential |
79c9ce57 PZ |
11562 | * perf_install_in_context() call for this new event to |
11563 | * serialize against exec() altering our credentials (and the | |
11564 | * perf_event_exit_task() that could imply). | |
11565 | */ | |
11566 | err = -EACCES; | |
11567 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
11568 | goto err_cred; | |
11569 | } | |
11570 | ||
79dff51e MF |
11571 | if (flags & PERF_FLAG_PID_CGROUP) |
11572 | cgroup_fd = pid; | |
11573 | ||
4dc0da86 | 11574 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11575 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11576 | if (IS_ERR(event)) { |
11577 | err = PTR_ERR(event); | |
79c9ce57 | 11578 | goto err_cred; |
d14b12d7 SE |
11579 | } |
11580 | ||
53b25335 VW |
11581 | if (is_sampling_event(event)) { |
11582 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11583 | err = -EOPNOTSUPP; |
53b25335 VW |
11584 | goto err_alloc; |
11585 | } | |
11586 | } | |
11587 | ||
89a1e187 PZ |
11588 | /* |
11589 | * Special case software events and allow them to be part of | |
11590 | * any hardware group. | |
11591 | */ | |
11592 | pmu = event->pmu; | |
b04243ef | 11593 | |
34f43927 PZ |
11594 | if (attr.use_clockid) { |
11595 | err = perf_event_set_clock(event, attr.clockid); | |
11596 | if (err) | |
11597 | goto err_alloc; | |
11598 | } | |
11599 | ||
4ff6a8de DCC |
11600 | if (pmu->task_ctx_nr == perf_sw_context) |
11601 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11602 | ||
a1150c20 SL |
11603 | if (group_leader) { |
11604 | if (is_software_event(event) && | |
11605 | !in_software_context(group_leader)) { | |
b04243ef | 11606 | /* |
a1150c20 SL |
11607 | * If the event is a sw event, but the group_leader |
11608 | * is on hw context. | |
b04243ef | 11609 | * |
a1150c20 SL |
11610 | * Allow the addition of software events to hw |
11611 | * groups, this is safe because software events | |
11612 | * never fail to schedule. | |
b04243ef | 11613 | */ |
a1150c20 SL |
11614 | pmu = group_leader->ctx->pmu; |
11615 | } else if (!is_software_event(event) && | |
11616 | is_software_event(group_leader) && | |
4ff6a8de | 11617 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11618 | /* |
11619 | * In case the group is a pure software group, and we | |
11620 | * try to add a hardware event, move the whole group to | |
11621 | * the hardware context. | |
11622 | */ | |
11623 | move_group = 1; | |
11624 | } | |
11625 | } | |
89a1e187 PZ |
11626 | |
11627 | /* | |
11628 | * Get the target context (task or percpu): | |
11629 | */ | |
4af57ef2 | 11630 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11631 | if (IS_ERR(ctx)) { |
11632 | err = PTR_ERR(ctx); | |
c6be5a5c | 11633 | goto err_alloc; |
89a1e187 PZ |
11634 | } |
11635 | ||
ccff286d | 11636 | /* |
cdd6c482 | 11637 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11638 | */ |
ac9721f3 | 11639 | if (group_leader) { |
dc86cabe | 11640 | err = -EINVAL; |
04289bb9 | 11641 | |
04289bb9 | 11642 | /* |
ccff286d IM |
11643 | * Do not allow a recursive hierarchy (this new sibling |
11644 | * becoming part of another group-sibling): | |
11645 | */ | |
11646 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11647 | goto err_context; |
34f43927 PZ |
11648 | |
11649 | /* All events in a group should have the same clock */ | |
11650 | if (group_leader->clock != event->clock) | |
11651 | goto err_context; | |
11652 | ||
ccff286d | 11653 | /* |
64aee2a9 MR |
11654 | * Make sure we're both events for the same CPU; |
11655 | * grouping events for different CPUs is broken; since | |
11656 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11657 | */ |
64aee2a9 MR |
11658 | if (group_leader->cpu != event->cpu) |
11659 | goto err_context; | |
c3c87e77 | 11660 | |
64aee2a9 MR |
11661 | /* |
11662 | * Make sure we're both on the same task, or both | |
11663 | * per-CPU events. | |
11664 | */ | |
11665 | if (group_leader->ctx->task != ctx->task) | |
11666 | goto err_context; | |
11667 | ||
11668 | /* | |
11669 | * Do not allow to attach to a group in a different task | |
11670 | * or CPU context. If we're moving SW events, we'll fix | |
11671 | * this up later, so allow that. | |
11672 | */ | |
11673 | if (!move_group && group_leader->ctx != ctx) | |
11674 | goto err_context; | |
b04243ef | 11675 | |
3b6f9e5c PM |
11676 | /* |
11677 | * Only a group leader can be exclusive or pinned | |
11678 | */ | |
0d48696f | 11679 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11680 | goto err_context; |
ac9721f3 PZ |
11681 | } |
11682 | ||
11683 | if (output_event) { | |
11684 | err = perf_event_set_output(event, output_event); | |
11685 | if (err) | |
c3f00c70 | 11686 | goto err_context; |
ac9721f3 | 11687 | } |
0793a61d | 11688 | |
a21b0b35 YD |
11689 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11690 | f_flags); | |
ea635c64 AV |
11691 | if (IS_ERR(event_file)) { |
11692 | err = PTR_ERR(event_file); | |
201c2f85 | 11693 | event_file = NULL; |
c3f00c70 | 11694 | goto err_context; |
ea635c64 | 11695 | } |
9b51f66d | 11696 | |
b04243ef | 11697 | if (move_group) { |
321027c1 PZ |
11698 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11699 | ||
84c4e620 PZ |
11700 | if (gctx->task == TASK_TOMBSTONE) { |
11701 | err = -ESRCH; | |
11702 | goto err_locked; | |
11703 | } | |
321027c1 PZ |
11704 | |
11705 | /* | |
11706 | * Check if we raced against another sys_perf_event_open() call | |
11707 | * moving the software group underneath us. | |
11708 | */ | |
11709 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11710 | /* | |
11711 | * If someone moved the group out from under us, check | |
11712 | * if this new event wound up on the same ctx, if so | |
11713 | * its the regular !move_group case, otherwise fail. | |
11714 | */ | |
11715 | if (gctx != ctx) { | |
11716 | err = -EINVAL; | |
11717 | goto err_locked; | |
11718 | } else { | |
11719 | perf_event_ctx_unlock(group_leader, gctx); | |
11720 | move_group = 0; | |
11721 | } | |
11722 | } | |
8a58ddae AS |
11723 | |
11724 | /* | |
11725 | * Failure to create exclusive events returns -EBUSY. | |
11726 | */ | |
11727 | err = -EBUSY; | |
11728 | if (!exclusive_event_installable(group_leader, ctx)) | |
11729 | goto err_locked; | |
11730 | ||
11731 | for_each_sibling_event(sibling, group_leader) { | |
11732 | if (!exclusive_event_installable(sibling, ctx)) | |
11733 | goto err_locked; | |
11734 | } | |
f55fc2a5 PZ |
11735 | } else { |
11736 | mutex_lock(&ctx->mutex); | |
11737 | } | |
11738 | ||
84c4e620 PZ |
11739 | if (ctx->task == TASK_TOMBSTONE) { |
11740 | err = -ESRCH; | |
11741 | goto err_locked; | |
11742 | } | |
11743 | ||
a723968c PZ |
11744 | if (!perf_event_validate_size(event)) { |
11745 | err = -E2BIG; | |
11746 | goto err_locked; | |
11747 | } | |
11748 | ||
a63fbed7 TG |
11749 | if (!task) { |
11750 | /* | |
11751 | * Check if the @cpu we're creating an event for is online. | |
11752 | * | |
11753 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11754 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11755 | */ | |
11756 | struct perf_cpu_context *cpuctx = | |
11757 | container_of(ctx, struct perf_cpu_context, ctx); | |
11758 | ||
11759 | if (!cpuctx->online) { | |
11760 | err = -ENODEV; | |
11761 | goto err_locked; | |
11762 | } | |
11763 | } | |
11764 | ||
da9ec3d3 MR |
11765 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
11766 | err = -EINVAL; | |
ab43762e | 11767 | goto err_locked; |
da9ec3d3 | 11768 | } |
a63fbed7 | 11769 | |
f55fc2a5 PZ |
11770 | /* |
11771 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11772 | * because we need to serialize with concurrent event creation. | |
11773 | */ | |
11774 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11775 | err = -EBUSY; |
11776 | goto err_locked; | |
11777 | } | |
f63a8daa | 11778 | |
f55fc2a5 PZ |
11779 | WARN_ON_ONCE(ctx->parent_ctx); |
11780 | ||
79c9ce57 PZ |
11781 | /* |
11782 | * This is the point on no return; we cannot fail hereafter. This is | |
11783 | * where we start modifying current state. | |
11784 | */ | |
11785 | ||
f55fc2a5 | 11786 | if (move_group) { |
f63a8daa PZ |
11787 | /* |
11788 | * See perf_event_ctx_lock() for comments on the details | |
11789 | * of swizzling perf_event::ctx. | |
11790 | */ | |
45a0e07a | 11791 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11792 | put_ctx(gctx); |
0231bb53 | 11793 | |
edb39592 | 11794 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11795 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11796 | put_ctx(gctx); |
11797 | } | |
b04243ef | 11798 | |
f63a8daa PZ |
11799 | /* |
11800 | * Wait for everybody to stop referencing the events through | |
11801 | * the old lists, before installing it on new lists. | |
11802 | */ | |
0cda4c02 | 11803 | synchronize_rcu(); |
f63a8daa | 11804 | |
8f95b435 PZI |
11805 | /* |
11806 | * Install the group siblings before the group leader. | |
11807 | * | |
11808 | * Because a group leader will try and install the entire group | |
11809 | * (through the sibling list, which is still in-tact), we can | |
11810 | * end up with siblings installed in the wrong context. | |
11811 | * | |
11812 | * By installing siblings first we NO-OP because they're not | |
11813 | * reachable through the group lists. | |
11814 | */ | |
edb39592 | 11815 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11816 | perf_event__state_init(sibling); |
9fc81d87 | 11817 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11818 | get_ctx(ctx); |
11819 | } | |
8f95b435 PZI |
11820 | |
11821 | /* | |
11822 | * Removing from the context ends up with disabled | |
11823 | * event. What we want here is event in the initial | |
11824 | * startup state, ready to be add into new context. | |
11825 | */ | |
11826 | perf_event__state_init(group_leader); | |
11827 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11828 | get_ctx(ctx); | |
bed5b25a AS |
11829 | } |
11830 | ||
f73e22ab PZ |
11831 | /* |
11832 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11833 | * that we're serialized against further additions and before | |
11834 | * perf_install_in_context() which is the point the event is active and | |
11835 | * can use these values. | |
11836 | */ | |
11837 | perf_event__header_size(event); | |
11838 | perf_event__id_header_size(event); | |
11839 | ||
78cd2c74 PZ |
11840 | event->owner = current; |
11841 | ||
e2d37cd2 | 11842 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11843 | perf_unpin_context(ctx); |
f63a8daa | 11844 | |
f55fc2a5 | 11845 | if (move_group) |
321027c1 | 11846 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11847 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11848 | |
79c9ce57 | 11849 | if (task) { |
69143038 | 11850 | mutex_unlock(&task->signal->exec_update_mutex); |
79c9ce57 PZ |
11851 | put_task_struct(task); |
11852 | } | |
11853 | ||
cdd6c482 IM |
11854 | mutex_lock(¤t->perf_event_mutex); |
11855 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11856 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11857 | |
8a49542c PZ |
11858 | /* |
11859 | * Drop the reference on the group_event after placing the | |
11860 | * new event on the sibling_list. This ensures destruction | |
11861 | * of the group leader will find the pointer to itself in | |
11862 | * perf_group_detach(). | |
11863 | */ | |
2903ff01 | 11864 | fdput(group); |
ea635c64 AV |
11865 | fd_install(event_fd, event_file); |
11866 | return event_fd; | |
0793a61d | 11867 | |
f55fc2a5 PZ |
11868 | err_locked: |
11869 | if (move_group) | |
321027c1 | 11870 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11871 | mutex_unlock(&ctx->mutex); |
11872 | /* err_file: */ | |
11873 | fput(event_file); | |
c3f00c70 | 11874 | err_context: |
fe4b04fa | 11875 | perf_unpin_context(ctx); |
ea635c64 | 11876 | put_ctx(ctx); |
c6be5a5c | 11877 | err_alloc: |
13005627 PZ |
11878 | /* |
11879 | * If event_file is set, the fput() above will have called ->release() | |
11880 | * and that will take care of freeing the event. | |
11881 | */ | |
11882 | if (!event_file) | |
11883 | free_event(event); | |
79c9ce57 PZ |
11884 | err_cred: |
11885 | if (task) | |
69143038 | 11886 | mutex_unlock(&task->signal->exec_update_mutex); |
1f4ee503 | 11887 | err_task: |
e7d0bc04 PZ |
11888 | if (task) |
11889 | put_task_struct(task); | |
89a1e187 | 11890 | err_group_fd: |
2903ff01 | 11891 | fdput(group); |
ea635c64 AV |
11892 | err_fd: |
11893 | put_unused_fd(event_fd); | |
dc86cabe | 11894 | return err; |
0793a61d TG |
11895 | } |
11896 | ||
fb0459d7 AV |
11897 | /** |
11898 | * perf_event_create_kernel_counter | |
11899 | * | |
11900 | * @attr: attributes of the counter to create | |
11901 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11902 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11903 | */ |
11904 | struct perf_event * | |
11905 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11906 | struct task_struct *task, |
4dc0da86 AK |
11907 | perf_overflow_handler_t overflow_handler, |
11908 | void *context) | |
fb0459d7 | 11909 | { |
fb0459d7 | 11910 | struct perf_event_context *ctx; |
c3f00c70 | 11911 | struct perf_event *event; |
fb0459d7 | 11912 | int err; |
d859e29f | 11913 | |
dce5affb AS |
11914 | /* |
11915 | * Grouping is not supported for kernel events, neither is 'AUX', | |
11916 | * make sure the caller's intentions are adjusted. | |
11917 | */ | |
11918 | if (attr->aux_output) | |
11919 | return ERR_PTR(-EINVAL); | |
11920 | ||
4dc0da86 | 11921 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11922 | overflow_handler, context, -1); |
c3f00c70 PZ |
11923 | if (IS_ERR(event)) { |
11924 | err = PTR_ERR(event); | |
11925 | goto err; | |
11926 | } | |
d859e29f | 11927 | |
f8697762 | 11928 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11929 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11930 | |
f25d8ba9 AS |
11931 | /* |
11932 | * Get the target context (task or percpu): | |
11933 | */ | |
4af57ef2 | 11934 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11935 | if (IS_ERR(ctx)) { |
11936 | err = PTR_ERR(ctx); | |
c3f00c70 | 11937 | goto err_free; |
d859e29f | 11938 | } |
fb0459d7 | 11939 | |
fb0459d7 AV |
11940 | WARN_ON_ONCE(ctx->parent_ctx); |
11941 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11942 | if (ctx->task == TASK_TOMBSTONE) { |
11943 | err = -ESRCH; | |
11944 | goto err_unlock; | |
11945 | } | |
11946 | ||
a63fbed7 TG |
11947 | if (!task) { |
11948 | /* | |
11949 | * Check if the @cpu we're creating an event for is online. | |
11950 | * | |
11951 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11952 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11953 | */ | |
11954 | struct perf_cpu_context *cpuctx = | |
11955 | container_of(ctx, struct perf_cpu_context, ctx); | |
11956 | if (!cpuctx->online) { | |
11957 | err = -ENODEV; | |
11958 | goto err_unlock; | |
11959 | } | |
11960 | } | |
11961 | ||
bed5b25a | 11962 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11963 | err = -EBUSY; |
84c4e620 | 11964 | goto err_unlock; |
bed5b25a AS |
11965 | } |
11966 | ||
4ce54af8 | 11967 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11968 | perf_unpin_context(ctx); |
fb0459d7 AV |
11969 | mutex_unlock(&ctx->mutex); |
11970 | ||
fb0459d7 AV |
11971 | return event; |
11972 | ||
84c4e620 PZ |
11973 | err_unlock: |
11974 | mutex_unlock(&ctx->mutex); | |
11975 | perf_unpin_context(ctx); | |
11976 | put_ctx(ctx); | |
c3f00c70 PZ |
11977 | err_free: |
11978 | free_event(event); | |
11979 | err: | |
c6567f64 | 11980 | return ERR_PTR(err); |
9b51f66d | 11981 | } |
fb0459d7 | 11982 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11983 | |
0cda4c02 YZ |
11984 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11985 | { | |
11986 | struct perf_event_context *src_ctx; | |
11987 | struct perf_event_context *dst_ctx; | |
11988 | struct perf_event *event, *tmp; | |
11989 | LIST_HEAD(events); | |
11990 | ||
11991 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11992 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11993 | ||
f63a8daa PZ |
11994 | /* |
11995 | * See perf_event_ctx_lock() for comments on the details | |
11996 | * of swizzling perf_event::ctx. | |
11997 | */ | |
11998 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11999 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12000 | event_entry) { | |
45a0e07a | 12001 | perf_remove_from_context(event, 0); |
9a545de0 | 12002 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12003 | put_ctx(src_ctx); |
9886167d | 12004 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12005 | } |
0cda4c02 | 12006 | |
8f95b435 PZI |
12007 | /* |
12008 | * Wait for the events to quiesce before re-instating them. | |
12009 | */ | |
0cda4c02 YZ |
12010 | synchronize_rcu(); |
12011 | ||
8f95b435 PZI |
12012 | /* |
12013 | * Re-instate events in 2 passes. | |
12014 | * | |
12015 | * Skip over group leaders and only install siblings on this first | |
12016 | * pass, siblings will not get enabled without a leader, however a | |
12017 | * leader will enable its siblings, even if those are still on the old | |
12018 | * context. | |
12019 | */ | |
12020 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12021 | if (event->group_leader == event) | |
12022 | continue; | |
12023 | ||
12024 | list_del(&event->migrate_entry); | |
12025 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12026 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12027 | account_event_cpu(event, dst_cpu); | |
12028 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12029 | get_ctx(dst_ctx); | |
12030 | } | |
12031 | ||
12032 | /* | |
12033 | * Once all the siblings are setup properly, install the group leaders | |
12034 | * to make it go. | |
12035 | */ | |
9886167d PZ |
12036 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12037 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12038 | if (event->state >= PERF_EVENT_STATE_OFF) |
12039 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12040 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12041 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12042 | get_ctx(dst_ctx); | |
12043 | } | |
12044 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12045 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12046 | } |
12047 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12048 | ||
cdd6c482 | 12049 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 12050 | struct task_struct *child) |
d859e29f | 12051 | { |
cdd6c482 | 12052 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12053 | u64 child_val; |
d859e29f | 12054 | |
cdd6c482 IM |
12055 | if (child_event->attr.inherit_stat) |
12056 | perf_event_read_event(child_event, child); | |
38b200d6 | 12057 | |
b5e58793 | 12058 | child_val = perf_event_count(child_event); |
d859e29f PM |
12059 | |
12060 | /* | |
12061 | * Add back the child's count to the parent's count: | |
12062 | */ | |
a6e6dea6 | 12063 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12064 | atomic64_add(child_event->total_time_enabled, |
12065 | &parent_event->child_total_time_enabled); | |
12066 | atomic64_add(child_event->total_time_running, | |
12067 | &parent_event->child_total_time_running); | |
d859e29f PM |
12068 | } |
12069 | ||
9b51f66d | 12070 | static void |
8ba289b8 PZ |
12071 | perf_event_exit_event(struct perf_event *child_event, |
12072 | struct perf_event_context *child_ctx, | |
12073 | struct task_struct *child) | |
9b51f66d | 12074 | { |
8ba289b8 PZ |
12075 | struct perf_event *parent_event = child_event->parent; |
12076 | ||
1903d50c PZ |
12077 | /* |
12078 | * Do not destroy the 'original' grouping; because of the context | |
12079 | * switch optimization the original events could've ended up in a | |
12080 | * random child task. | |
12081 | * | |
12082 | * If we were to destroy the original group, all group related | |
12083 | * operations would cease to function properly after this random | |
12084 | * child dies. | |
12085 | * | |
12086 | * Do destroy all inherited groups, we don't care about those | |
12087 | * and being thorough is better. | |
12088 | */ | |
32132a3d PZ |
12089 | raw_spin_lock_irq(&child_ctx->lock); |
12090 | WARN_ON_ONCE(child_ctx->is_active); | |
12091 | ||
8ba289b8 | 12092 | if (parent_event) |
32132a3d PZ |
12093 | perf_group_detach(child_event); |
12094 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 12095 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 12096 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 12097 | |
9b51f66d | 12098 | /* |
8ba289b8 | 12099 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 12100 | */ |
8ba289b8 | 12101 | if (!parent_event) { |
179033b3 | 12102 | perf_event_wakeup(child_event); |
8ba289b8 | 12103 | return; |
4bcf349a | 12104 | } |
8ba289b8 PZ |
12105 | /* |
12106 | * Child events can be cleaned up. | |
12107 | */ | |
12108 | ||
12109 | sync_child_event(child_event, child); | |
12110 | ||
12111 | /* | |
12112 | * Remove this event from the parent's list | |
12113 | */ | |
12114 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
12115 | mutex_lock(&parent_event->child_mutex); | |
12116 | list_del_init(&child_event->child_list); | |
12117 | mutex_unlock(&parent_event->child_mutex); | |
12118 | ||
12119 | /* | |
12120 | * Kick perf_poll() for is_event_hup(). | |
12121 | */ | |
12122 | perf_event_wakeup(parent_event); | |
12123 | free_event(child_event); | |
12124 | put_event(parent_event); | |
9b51f66d IM |
12125 | } |
12126 | ||
8dc85d54 | 12127 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12128 | { |
211de6eb | 12129 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12130 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12131 | |
12132 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12133 | |
6a3351b6 | 12134 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12135 | if (!child_ctx) |
9b51f66d IM |
12136 | return; |
12137 | ||
ad3a37de | 12138 | /* |
6a3351b6 PZ |
12139 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12140 | * ctx::mutex over the entire thing. This serializes against almost | |
12141 | * everything that wants to access the ctx. | |
12142 | * | |
12143 | * The exception is sys_perf_event_open() / | |
12144 | * perf_event_create_kernel_count() which does find_get_context() | |
12145 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12146 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12147 | */ |
6a3351b6 | 12148 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12149 | |
12150 | /* | |
6a3351b6 PZ |
12151 | * In a single ctx::lock section, de-schedule the events and detach the |
12152 | * context from the task such that we cannot ever get it scheduled back | |
12153 | * in. | |
c93f7669 | 12154 | */ |
6a3351b6 | 12155 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12156 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12157 | |
71a851b4 | 12158 | /* |
63b6da39 PZ |
12159 | * Now that the context is inactive, destroy the task <-> ctx relation |
12160 | * and mark the context dead. | |
71a851b4 | 12161 | */ |
63b6da39 PZ |
12162 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12163 | put_ctx(child_ctx); /* cannot be last */ | |
12164 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12165 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12166 | |
211de6eb | 12167 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12168 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12169 | |
211de6eb PZ |
12170 | if (clone_ctx) |
12171 | put_ctx(clone_ctx); | |
4a1c0f26 | 12172 | |
9f498cc5 | 12173 | /* |
cdd6c482 IM |
12174 | * Report the task dead after unscheduling the events so that we |
12175 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12176 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12177 | */ |
cdd6c482 | 12178 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12179 | |
ebf905fc | 12180 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 12181 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 12182 | |
a63eaf34 PM |
12183 | mutex_unlock(&child_ctx->mutex); |
12184 | ||
12185 | put_ctx(child_ctx); | |
9b51f66d IM |
12186 | } |
12187 | ||
8dc85d54 PZ |
12188 | /* |
12189 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12190 | * |
69143038 | 12191 | * Can be called with exec_update_mutex held when called from |
79c9ce57 | 12192 | * install_exec_creds(). |
8dc85d54 PZ |
12193 | */ |
12194 | void perf_event_exit_task(struct task_struct *child) | |
12195 | { | |
8882135b | 12196 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12197 | int ctxn; |
12198 | ||
8882135b PZ |
12199 | mutex_lock(&child->perf_event_mutex); |
12200 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12201 | owner_entry) { | |
12202 | list_del_init(&event->owner_entry); | |
12203 | ||
12204 | /* | |
12205 | * Ensure the list deletion is visible before we clear | |
12206 | * the owner, closes a race against perf_release() where | |
12207 | * we need to serialize on the owner->perf_event_mutex. | |
12208 | */ | |
f47c02c0 | 12209 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12210 | } |
12211 | mutex_unlock(&child->perf_event_mutex); | |
12212 | ||
8dc85d54 PZ |
12213 | for_each_task_context_nr(ctxn) |
12214 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12215 | |
12216 | /* | |
12217 | * The perf_event_exit_task_context calls perf_event_task | |
12218 | * with child's task_ctx, which generates EXIT events for | |
12219 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12220 | * At this point we need to send EXIT events to cpu contexts. | |
12221 | */ | |
12222 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12223 | } |
12224 | ||
889ff015 FW |
12225 | static void perf_free_event(struct perf_event *event, |
12226 | struct perf_event_context *ctx) | |
12227 | { | |
12228 | struct perf_event *parent = event->parent; | |
12229 | ||
12230 | if (WARN_ON_ONCE(!parent)) | |
12231 | return; | |
12232 | ||
12233 | mutex_lock(&parent->child_mutex); | |
12234 | list_del_init(&event->child_list); | |
12235 | mutex_unlock(&parent->child_mutex); | |
12236 | ||
a6fa941d | 12237 | put_event(parent); |
889ff015 | 12238 | |
652884fe | 12239 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12240 | perf_group_detach(event); |
889ff015 | 12241 | list_del_event(event, ctx); |
652884fe | 12242 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12243 | free_event(event); |
12244 | } | |
12245 | ||
bbbee908 | 12246 | /* |
1cf8dfe8 PZ |
12247 | * Free a context as created by inheritance by perf_event_init_task() below, |
12248 | * used by fork() in case of fail. | |
652884fe | 12249 | * |
1cf8dfe8 PZ |
12250 | * Even though the task has never lived, the context and events have been |
12251 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12252 | */ |
cdd6c482 | 12253 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12254 | { |
8dc85d54 | 12255 | struct perf_event_context *ctx; |
cdd6c482 | 12256 | struct perf_event *event, *tmp; |
8dc85d54 | 12257 | int ctxn; |
bbbee908 | 12258 | |
8dc85d54 PZ |
12259 | for_each_task_context_nr(ctxn) { |
12260 | ctx = task->perf_event_ctxp[ctxn]; | |
12261 | if (!ctx) | |
12262 | continue; | |
bbbee908 | 12263 | |
8dc85d54 | 12264 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12265 | raw_spin_lock_irq(&ctx->lock); |
12266 | /* | |
12267 | * Destroy the task <-> ctx relation and mark the context dead. | |
12268 | * | |
12269 | * This is important because even though the task hasn't been | |
12270 | * exposed yet the context has been (through child_list). | |
12271 | */ | |
12272 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12273 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12274 | put_task_struct(task); /* cannot be last */ | |
12275 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12276 | |
15121c78 | 12277 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12278 | perf_free_event(event, ctx); |
bbbee908 | 12279 | |
8dc85d54 | 12280 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12281 | |
12282 | /* | |
12283 | * perf_event_release_kernel() could've stolen some of our | |
12284 | * child events and still have them on its free_list. In that | |
12285 | * case we must wait for these events to have been freed (in | |
12286 | * particular all their references to this task must've been | |
12287 | * dropped). | |
12288 | * | |
12289 | * Without this copy_process() will unconditionally free this | |
12290 | * task (irrespective of its reference count) and | |
12291 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12292 | * use-after-free. | |
12293 | * | |
12294 | * Wait for all events to drop their context reference. | |
12295 | */ | |
12296 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12297 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12298 | } |
889ff015 FW |
12299 | } |
12300 | ||
4e231c79 PZ |
12301 | void perf_event_delayed_put(struct task_struct *task) |
12302 | { | |
12303 | int ctxn; | |
12304 | ||
12305 | for_each_task_context_nr(ctxn) | |
12306 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12307 | } | |
12308 | ||
e03e7ee3 | 12309 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12310 | { |
02e5ad97 | 12311 | struct file *file = fget(fd); |
e03e7ee3 AS |
12312 | if (!file) |
12313 | return ERR_PTR(-EBADF); | |
ffe8690c | 12314 | |
e03e7ee3 AS |
12315 | if (file->f_op != &perf_fops) { |
12316 | fput(file); | |
12317 | return ERR_PTR(-EBADF); | |
12318 | } | |
ffe8690c | 12319 | |
e03e7ee3 | 12320 | return file; |
ffe8690c KX |
12321 | } |
12322 | ||
f8d959a5 YS |
12323 | const struct perf_event *perf_get_event(struct file *file) |
12324 | { | |
12325 | if (file->f_op != &perf_fops) | |
12326 | return ERR_PTR(-EINVAL); | |
12327 | ||
12328 | return file->private_data; | |
12329 | } | |
12330 | ||
ffe8690c KX |
12331 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12332 | { | |
12333 | if (!event) | |
12334 | return ERR_PTR(-EINVAL); | |
12335 | ||
12336 | return &event->attr; | |
12337 | } | |
12338 | ||
97dee4f3 | 12339 | /* |
788faab7 | 12340 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12341 | * |
12342 | * Returns: | |
12343 | * - valid pointer on success | |
12344 | * - NULL for orphaned events | |
12345 | * - IS_ERR() on error | |
97dee4f3 PZ |
12346 | */ |
12347 | static struct perf_event * | |
12348 | inherit_event(struct perf_event *parent_event, | |
12349 | struct task_struct *parent, | |
12350 | struct perf_event_context *parent_ctx, | |
12351 | struct task_struct *child, | |
12352 | struct perf_event *group_leader, | |
12353 | struct perf_event_context *child_ctx) | |
12354 | { | |
8ca2bd41 | 12355 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12356 | struct perf_event *child_event; |
cee010ec | 12357 | unsigned long flags; |
97dee4f3 PZ |
12358 | |
12359 | /* | |
12360 | * Instead of creating recursive hierarchies of events, | |
12361 | * we link inherited events back to the original parent, | |
12362 | * which has a filp for sure, which we use as the reference | |
12363 | * count: | |
12364 | */ | |
12365 | if (parent_event->parent) | |
12366 | parent_event = parent_event->parent; | |
12367 | ||
12368 | child_event = perf_event_alloc(&parent_event->attr, | |
12369 | parent_event->cpu, | |
d580ff86 | 12370 | child, |
97dee4f3 | 12371 | group_leader, parent_event, |
79dff51e | 12372 | NULL, NULL, -1); |
97dee4f3 PZ |
12373 | if (IS_ERR(child_event)) |
12374 | return child_event; | |
a6fa941d | 12375 | |
313ccb96 JO |
12376 | |
12377 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12378 | !child_ctx->task_ctx_data) { | |
12379 | struct pmu *pmu = child_event->pmu; | |
12380 | ||
12381 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
12382 | GFP_KERNEL); | |
12383 | if (!child_ctx->task_ctx_data) { | |
12384 | free_event(child_event); | |
697d8778 | 12385 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12386 | } |
12387 | } | |
12388 | ||
c6e5b732 PZ |
12389 | /* |
12390 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12391 | * must be under the same lock in order to serialize against | |
12392 | * perf_event_release_kernel(), such that either we must observe | |
12393 | * is_orphaned_event() or they will observe us on the child_list. | |
12394 | */ | |
12395 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12396 | if (is_orphaned_event(parent_event) || |
12397 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12398 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12399 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12400 | free_event(child_event); |
12401 | return NULL; | |
12402 | } | |
12403 | ||
97dee4f3 PZ |
12404 | get_ctx(child_ctx); |
12405 | ||
12406 | /* | |
12407 | * Make the child state follow the state of the parent event, | |
12408 | * not its attr.disabled bit. We hold the parent's mutex, | |
12409 | * so we won't race with perf_event_{en, dis}able_family. | |
12410 | */ | |
1929def9 | 12411 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12412 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12413 | else | |
12414 | child_event->state = PERF_EVENT_STATE_OFF; | |
12415 | ||
12416 | if (parent_event->attr.freq) { | |
12417 | u64 sample_period = parent_event->hw.sample_period; | |
12418 | struct hw_perf_event *hwc = &child_event->hw; | |
12419 | ||
12420 | hwc->sample_period = sample_period; | |
12421 | hwc->last_period = sample_period; | |
12422 | ||
12423 | local64_set(&hwc->period_left, sample_period); | |
12424 | } | |
12425 | ||
12426 | child_event->ctx = child_ctx; | |
12427 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12428 | child_event->overflow_handler_context |
12429 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12430 | |
614b6780 TG |
12431 | /* |
12432 | * Precalculate sample_data sizes | |
12433 | */ | |
12434 | perf_event__header_size(child_event); | |
6844c09d | 12435 | perf_event__id_header_size(child_event); |
614b6780 | 12436 | |
97dee4f3 PZ |
12437 | /* |
12438 | * Link it up in the child's context: | |
12439 | */ | |
cee010ec | 12440 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12441 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12442 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12443 | |
97dee4f3 PZ |
12444 | /* |
12445 | * Link this into the parent event's child list | |
12446 | */ | |
97dee4f3 PZ |
12447 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12448 | mutex_unlock(&parent_event->child_mutex); | |
12449 | ||
12450 | return child_event; | |
12451 | } | |
12452 | ||
d8a8cfc7 PZ |
12453 | /* |
12454 | * Inherits an event group. | |
12455 | * | |
12456 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12457 | * This matches with perf_event_release_kernel() removing all child events. | |
12458 | * | |
12459 | * Returns: | |
12460 | * - 0 on success | |
12461 | * - <0 on error | |
12462 | */ | |
97dee4f3 PZ |
12463 | static int inherit_group(struct perf_event *parent_event, |
12464 | struct task_struct *parent, | |
12465 | struct perf_event_context *parent_ctx, | |
12466 | struct task_struct *child, | |
12467 | struct perf_event_context *child_ctx) | |
12468 | { | |
12469 | struct perf_event *leader; | |
12470 | struct perf_event *sub; | |
12471 | struct perf_event *child_ctr; | |
12472 | ||
12473 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12474 | child, NULL, child_ctx); | |
12475 | if (IS_ERR(leader)) | |
12476 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12477 | /* |
12478 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12479 | * case inherit_event() will create individual events, similar to what | |
12480 | * perf_group_detach() would do anyway. | |
12481 | */ | |
edb39592 | 12482 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12483 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12484 | child, leader, child_ctx); | |
12485 | if (IS_ERR(child_ctr)) | |
12486 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12487 | |
00496fe5 | 12488 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12489 | !perf_get_aux_event(child_ctr, leader)) |
12490 | return -EINVAL; | |
97dee4f3 PZ |
12491 | } |
12492 | return 0; | |
889ff015 FW |
12493 | } |
12494 | ||
d8a8cfc7 PZ |
12495 | /* |
12496 | * Creates the child task context and tries to inherit the event-group. | |
12497 | * | |
12498 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12499 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12500 | * consistent with perf_event_release_kernel() removing all child events. | |
12501 | * | |
12502 | * Returns: | |
12503 | * - 0 on success | |
12504 | * - <0 on error | |
12505 | */ | |
889ff015 FW |
12506 | static int |
12507 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12508 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12509 | struct task_struct *child, int ctxn, |
889ff015 FW |
12510 | int *inherited_all) |
12511 | { | |
12512 | int ret; | |
8dc85d54 | 12513 | struct perf_event_context *child_ctx; |
889ff015 FW |
12514 | |
12515 | if (!event->attr.inherit) { | |
12516 | *inherited_all = 0; | |
12517 | return 0; | |
bbbee908 PZ |
12518 | } |
12519 | ||
fe4b04fa | 12520 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12521 | if (!child_ctx) { |
12522 | /* | |
12523 | * This is executed from the parent task context, so | |
12524 | * inherit events that have been marked for cloning. | |
12525 | * First allocate and initialize a context for the | |
12526 | * child. | |
12527 | */ | |
734df5ab | 12528 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12529 | if (!child_ctx) |
12530 | return -ENOMEM; | |
bbbee908 | 12531 | |
8dc85d54 | 12532 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12533 | } |
12534 | ||
12535 | ret = inherit_group(event, parent, parent_ctx, | |
12536 | child, child_ctx); | |
12537 | ||
12538 | if (ret) | |
12539 | *inherited_all = 0; | |
12540 | ||
12541 | return ret; | |
bbbee908 PZ |
12542 | } |
12543 | ||
9b51f66d | 12544 | /* |
cdd6c482 | 12545 | * Initialize the perf_event context in task_struct |
9b51f66d | 12546 | */ |
985c8dcb | 12547 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12548 | { |
889ff015 | 12549 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12550 | struct perf_event_context *cloned_ctx; |
12551 | struct perf_event *event; | |
9b51f66d | 12552 | struct task_struct *parent = current; |
564c2b21 | 12553 | int inherited_all = 1; |
dddd3379 | 12554 | unsigned long flags; |
6ab423e0 | 12555 | int ret = 0; |
9b51f66d | 12556 | |
8dc85d54 | 12557 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12558 | return 0; |
12559 | ||
ad3a37de | 12560 | /* |
25346b93 PM |
12561 | * If the parent's context is a clone, pin it so it won't get |
12562 | * swapped under us. | |
ad3a37de | 12563 | */ |
8dc85d54 | 12564 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12565 | if (!parent_ctx) |
12566 | return 0; | |
25346b93 | 12567 | |
ad3a37de PM |
12568 | /* |
12569 | * No need to check if parent_ctx != NULL here; since we saw | |
12570 | * it non-NULL earlier, the only reason for it to become NULL | |
12571 | * is if we exit, and since we're currently in the middle of | |
12572 | * a fork we can't be exiting at the same time. | |
12573 | */ | |
ad3a37de | 12574 | |
9b51f66d IM |
12575 | /* |
12576 | * Lock the parent list. No need to lock the child - not PID | |
12577 | * hashed yet and not running, so nobody can access it. | |
12578 | */ | |
d859e29f | 12579 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12580 | |
12581 | /* | |
12582 | * We dont have to disable NMIs - we are only looking at | |
12583 | * the list, not manipulating it: | |
12584 | */ | |
6e6804d2 | 12585 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12586 | ret = inherit_task_group(event, parent, parent_ctx, |
12587 | child, ctxn, &inherited_all); | |
889ff015 | 12588 | if (ret) |
e7cc4865 | 12589 | goto out_unlock; |
889ff015 | 12590 | } |
b93f7978 | 12591 | |
dddd3379 TG |
12592 | /* |
12593 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12594 | * to allocations, but we need to prevent rotation because | |
12595 | * rotate_ctx() will change the list from interrupt context. | |
12596 | */ | |
12597 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12598 | parent_ctx->rotate_disable = 1; | |
12599 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12600 | ||
6e6804d2 | 12601 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12602 | ret = inherit_task_group(event, parent, parent_ctx, |
12603 | child, ctxn, &inherited_all); | |
889ff015 | 12604 | if (ret) |
e7cc4865 | 12605 | goto out_unlock; |
564c2b21 PM |
12606 | } |
12607 | ||
dddd3379 TG |
12608 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12609 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12610 | |
8dc85d54 | 12611 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12612 | |
05cbaa28 | 12613 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12614 | /* |
12615 | * Mark the child context as a clone of the parent | |
12616 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12617 | * |
12618 | * Note that if the parent is a clone, the holding of | |
12619 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12620 | */ |
c5ed5145 | 12621 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12622 | if (cloned_ctx) { |
12623 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12624 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12625 | } else { |
12626 | child_ctx->parent_ctx = parent_ctx; | |
12627 | child_ctx->parent_gen = parent_ctx->generation; | |
12628 | } | |
12629 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12630 | } |
12631 | ||
c5ed5145 | 12632 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12633 | out_unlock: |
d859e29f | 12634 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12635 | |
25346b93 | 12636 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12637 | put_ctx(parent_ctx); |
ad3a37de | 12638 | |
6ab423e0 | 12639 | return ret; |
9b51f66d IM |
12640 | } |
12641 | ||
8dc85d54 PZ |
12642 | /* |
12643 | * Initialize the perf_event context in task_struct | |
12644 | */ | |
12645 | int perf_event_init_task(struct task_struct *child) | |
12646 | { | |
12647 | int ctxn, ret; | |
12648 | ||
8550d7cb ON |
12649 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12650 | mutex_init(&child->perf_event_mutex); | |
12651 | INIT_LIST_HEAD(&child->perf_event_list); | |
12652 | ||
8dc85d54 PZ |
12653 | for_each_task_context_nr(ctxn) { |
12654 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12655 | if (ret) { |
12656 | perf_event_free_task(child); | |
8dc85d54 | 12657 | return ret; |
6c72e350 | 12658 | } |
8dc85d54 PZ |
12659 | } |
12660 | ||
12661 | return 0; | |
12662 | } | |
12663 | ||
220b140b PM |
12664 | static void __init perf_event_init_all_cpus(void) |
12665 | { | |
b28ab83c | 12666 | struct swevent_htable *swhash; |
220b140b | 12667 | int cpu; |
220b140b | 12668 | |
a63fbed7 TG |
12669 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12670 | ||
220b140b | 12671 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12672 | swhash = &per_cpu(swevent_htable, cpu); |
12673 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12674 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12675 | |
12676 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12677 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12678 | |
058fe1c0 DCC |
12679 | #ifdef CONFIG_CGROUP_PERF |
12680 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12681 | #endif | |
e48c1788 | 12682 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12683 | } |
12684 | } | |
12685 | ||
d18bf422 | 12686 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12687 | { |
108b02cf | 12688 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12689 | |
b28ab83c | 12690 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12691 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12692 | struct swevent_hlist *hlist; |
12693 | ||
b28ab83c PZ |
12694 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12695 | WARN_ON(!hlist); | |
12696 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12697 | } |
b28ab83c | 12698 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12699 | } |
12700 | ||
2965faa5 | 12701 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12702 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12703 | { |
108b02cf | 12704 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12705 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12706 | struct perf_event *event; | |
0793a61d | 12707 | |
fae3fde6 | 12708 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12709 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12710 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12711 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12712 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12713 | } |
108b02cf PZ |
12714 | |
12715 | static void perf_event_exit_cpu_context(int cpu) | |
12716 | { | |
a63fbed7 | 12717 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12718 | struct perf_event_context *ctx; |
12719 | struct pmu *pmu; | |
108b02cf | 12720 | |
a63fbed7 TG |
12721 | mutex_lock(&pmus_lock); |
12722 | list_for_each_entry(pmu, &pmus, entry) { | |
12723 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12724 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12725 | |
12726 | mutex_lock(&ctx->mutex); | |
12727 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12728 | cpuctx->online = 0; |
108b02cf PZ |
12729 | mutex_unlock(&ctx->mutex); |
12730 | } | |
a63fbed7 TG |
12731 | cpumask_clear_cpu(cpu, perf_online_mask); |
12732 | mutex_unlock(&pmus_lock); | |
108b02cf | 12733 | } |
00e16c3d TG |
12734 | #else |
12735 | ||
12736 | static void perf_event_exit_cpu_context(int cpu) { } | |
12737 | ||
12738 | #endif | |
108b02cf | 12739 | |
a63fbed7 TG |
12740 | int perf_event_init_cpu(unsigned int cpu) |
12741 | { | |
12742 | struct perf_cpu_context *cpuctx; | |
12743 | struct perf_event_context *ctx; | |
12744 | struct pmu *pmu; | |
12745 | ||
12746 | perf_swevent_init_cpu(cpu); | |
12747 | ||
12748 | mutex_lock(&pmus_lock); | |
12749 | cpumask_set_cpu(cpu, perf_online_mask); | |
12750 | list_for_each_entry(pmu, &pmus, entry) { | |
12751 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12752 | ctx = &cpuctx->ctx; | |
12753 | ||
12754 | mutex_lock(&ctx->mutex); | |
12755 | cpuctx->online = 1; | |
12756 | mutex_unlock(&ctx->mutex); | |
12757 | } | |
12758 | mutex_unlock(&pmus_lock); | |
12759 | ||
12760 | return 0; | |
12761 | } | |
12762 | ||
00e16c3d | 12763 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12764 | { |
e3703f8c | 12765 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12766 | return 0; |
0793a61d | 12767 | } |
0793a61d | 12768 | |
c277443c PZ |
12769 | static int |
12770 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12771 | { | |
12772 | int cpu; | |
12773 | ||
12774 | for_each_online_cpu(cpu) | |
12775 | perf_event_exit_cpu(cpu); | |
12776 | ||
12777 | return NOTIFY_OK; | |
12778 | } | |
12779 | ||
12780 | /* | |
12781 | * Run the perf reboot notifier at the very last possible moment so that | |
12782 | * the generic watchdog code runs as long as possible. | |
12783 | */ | |
12784 | static struct notifier_block perf_reboot_notifier = { | |
12785 | .notifier_call = perf_reboot, | |
12786 | .priority = INT_MIN, | |
12787 | }; | |
12788 | ||
cdd6c482 | 12789 | void __init perf_event_init(void) |
0793a61d | 12790 | { |
3c502e7a JW |
12791 | int ret; |
12792 | ||
2e80a82a PZ |
12793 | idr_init(&pmu_idr); |
12794 | ||
220b140b | 12795 | perf_event_init_all_cpus(); |
b0a873eb | 12796 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12797 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12798 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12799 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12800 | perf_tp_register(); |
00e16c3d | 12801 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12802 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12803 | |
12804 | ret = init_hw_breakpoint(); | |
12805 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12806 | |
b01c3a00 JO |
12807 | /* |
12808 | * Build time assertion that we keep the data_head at the intended | |
12809 | * location. IOW, validation we got the __reserved[] size right. | |
12810 | */ | |
12811 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12812 | != 1024); | |
0793a61d | 12813 | } |
abe43400 | 12814 | |
fd979c01 CS |
12815 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12816 | char *page) | |
12817 | { | |
12818 | struct perf_pmu_events_attr *pmu_attr = | |
12819 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12820 | ||
12821 | if (pmu_attr->event_str) | |
12822 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12823 | ||
12824 | return 0; | |
12825 | } | |
675965b0 | 12826 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12827 | |
abe43400 PZ |
12828 | static int __init perf_event_sysfs_init(void) |
12829 | { | |
12830 | struct pmu *pmu; | |
12831 | int ret; | |
12832 | ||
12833 | mutex_lock(&pmus_lock); | |
12834 | ||
12835 | ret = bus_register(&pmu_bus); | |
12836 | if (ret) | |
12837 | goto unlock; | |
12838 | ||
12839 | list_for_each_entry(pmu, &pmus, entry) { | |
12840 | if (!pmu->name || pmu->type < 0) | |
12841 | continue; | |
12842 | ||
12843 | ret = pmu_dev_alloc(pmu); | |
12844 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12845 | } | |
12846 | pmu_bus_running = 1; | |
12847 | ret = 0; | |
12848 | ||
12849 | unlock: | |
12850 | mutex_unlock(&pmus_lock); | |
12851 | ||
12852 | return ret; | |
12853 | } | |
12854 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12855 | |
12856 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12857 | static struct cgroup_subsys_state * |
12858 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12859 | { |
12860 | struct perf_cgroup *jc; | |
e5d1367f | 12861 | |
1b15d055 | 12862 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12863 | if (!jc) |
12864 | return ERR_PTR(-ENOMEM); | |
12865 | ||
e5d1367f SE |
12866 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12867 | if (!jc->info) { | |
12868 | kfree(jc); | |
12869 | return ERR_PTR(-ENOMEM); | |
12870 | } | |
12871 | ||
e5d1367f SE |
12872 | return &jc->css; |
12873 | } | |
12874 | ||
eb95419b | 12875 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12876 | { |
eb95419b TH |
12877 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12878 | ||
e5d1367f SE |
12879 | free_percpu(jc->info); |
12880 | kfree(jc); | |
12881 | } | |
12882 | ||
96aaab68 NK |
12883 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
12884 | { | |
12885 | perf_event_cgroup(css->cgroup); | |
12886 | return 0; | |
12887 | } | |
12888 | ||
e5d1367f SE |
12889 | static int __perf_cgroup_move(void *info) |
12890 | { | |
12891 | struct task_struct *task = info; | |
ddaaf4e2 | 12892 | rcu_read_lock(); |
e5d1367f | 12893 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12894 | rcu_read_unlock(); |
e5d1367f SE |
12895 | return 0; |
12896 | } | |
12897 | ||
1f7dd3e5 | 12898 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12899 | { |
bb9d97b6 | 12900 | struct task_struct *task; |
1f7dd3e5 | 12901 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12902 | |
1f7dd3e5 | 12903 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12904 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12905 | } |
12906 | ||
073219e9 | 12907 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12908 | .css_alloc = perf_cgroup_css_alloc, |
12909 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 12910 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 12911 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12912 | /* |
12913 | * Implicitly enable on dfl hierarchy so that perf events can | |
12914 | * always be filtered by cgroup2 path as long as perf_event | |
12915 | * controller is not mounted on a legacy hierarchy. | |
12916 | */ | |
12917 | .implicit_on_dfl = true, | |
8cfd8147 | 12918 | .threaded = true, |
e5d1367f SE |
12919 | }; |
12920 | #endif /* CONFIG_CGROUP_PERF */ |