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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 | 30 | #include <linux/hardirq.h> |
03911132 | 31 | #include <linux/hugetlb.h> |
b9cacc7b | 32 | #include <linux/rculist.h> |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
375637bc AS |
47 | #include <linux/namei.h> |
48 | #include <linux/parser.h> | |
e6017571 | 49 | #include <linux/sched/clock.h> |
6e84f315 | 50 | #include <linux/sched/mm.h> |
e4222673 HB |
51 | #include <linux/proc_ns.h> |
52 | #include <linux/mount.h> | |
6eef8a71 | 53 | #include <linux/min_heap.h> |
0793a61d | 54 | |
76369139 FW |
55 | #include "internal.h" |
56 | ||
4e193bd4 TB |
57 | #include <asm/irq_regs.h> |
58 | ||
272325c4 PZ |
59 | typedef int (*remote_function_f)(void *); |
60 | ||
fe4b04fa | 61 | struct remote_function_call { |
e7e7ee2e | 62 | struct task_struct *p; |
272325c4 | 63 | remote_function_f func; |
e7e7ee2e IM |
64 | void *info; |
65 | int ret; | |
fe4b04fa PZ |
66 | }; |
67 | ||
68 | static void remote_function(void *data) | |
69 | { | |
70 | struct remote_function_call *tfc = data; | |
71 | struct task_struct *p = tfc->p; | |
72 | ||
73 | if (p) { | |
0da4cf3e PZ |
74 | /* -EAGAIN */ |
75 | if (task_cpu(p) != smp_processor_id()) | |
76 | return; | |
77 | ||
78 | /* | |
79 | * Now that we're on right CPU with IRQs disabled, we can test | |
80 | * if we hit the right task without races. | |
81 | */ | |
82 | ||
83 | tfc->ret = -ESRCH; /* No such (running) process */ | |
84 | if (p != current) | |
fe4b04fa PZ |
85 | return; |
86 | } | |
87 | ||
88 | tfc->ret = tfc->func(tfc->info); | |
89 | } | |
90 | ||
91 | /** | |
92 | * task_function_call - call a function on the cpu on which a task runs | |
93 | * @p: the task to evaluate | |
94 | * @func: the function to be called | |
95 | * @info: the function call argument | |
96 | * | |
97 | * Calls the function @func when the task is currently running. This might | |
98 | * be on the current CPU, which just calls the function directly | |
99 | * | |
100 | * returns: @func return value, or | |
101 | * -ESRCH - when the process isn't running | |
102 | * -EAGAIN - when the process moved away | |
103 | */ | |
104 | static int | |
272325c4 | 105 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
106 | { |
107 | struct remote_function_call data = { | |
e7e7ee2e IM |
108 | .p = p, |
109 | .func = func, | |
110 | .info = info, | |
0da4cf3e | 111 | .ret = -EAGAIN, |
fe4b04fa | 112 | }; |
0da4cf3e | 113 | int ret; |
fe4b04fa | 114 | |
0da4cf3e PZ |
115 | do { |
116 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
117 | if (!ret) | |
118 | ret = data.ret; | |
119 | } while (ret == -EAGAIN); | |
fe4b04fa | 120 | |
0da4cf3e | 121 | return ret; |
fe4b04fa PZ |
122 | } |
123 | ||
124 | /** | |
125 | * cpu_function_call - call a function on the cpu | |
126 | * @func: the function to be called | |
127 | * @info: the function call argument | |
128 | * | |
129 | * Calls the function @func on the remote cpu. | |
130 | * | |
131 | * returns: @func return value or -ENXIO when the cpu is offline | |
132 | */ | |
272325c4 | 133 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
134 | { |
135 | struct remote_function_call data = { | |
e7e7ee2e IM |
136 | .p = NULL, |
137 | .func = func, | |
138 | .info = info, | |
139 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
140 | }; |
141 | ||
142 | smp_call_function_single(cpu, remote_function, &data, 1); | |
143 | ||
144 | return data.ret; | |
145 | } | |
146 | ||
fae3fde6 PZ |
147 | static inline struct perf_cpu_context * |
148 | __get_cpu_context(struct perf_event_context *ctx) | |
149 | { | |
150 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
151 | } | |
152 | ||
153 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
154 | struct perf_event_context *ctx) | |
0017960f | 155 | { |
fae3fde6 PZ |
156 | raw_spin_lock(&cpuctx->ctx.lock); |
157 | if (ctx) | |
158 | raw_spin_lock(&ctx->lock); | |
159 | } | |
160 | ||
161 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
162 | struct perf_event_context *ctx) | |
163 | { | |
164 | if (ctx) | |
165 | raw_spin_unlock(&ctx->lock); | |
166 | raw_spin_unlock(&cpuctx->ctx.lock); | |
167 | } | |
168 | ||
63b6da39 PZ |
169 | #define TASK_TOMBSTONE ((void *)-1L) |
170 | ||
171 | static bool is_kernel_event(struct perf_event *event) | |
172 | { | |
f47c02c0 | 173 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
174 | } |
175 | ||
39a43640 PZ |
176 | /* |
177 | * On task ctx scheduling... | |
178 | * | |
179 | * When !ctx->nr_events a task context will not be scheduled. This means | |
180 | * we can disable the scheduler hooks (for performance) without leaving | |
181 | * pending task ctx state. | |
182 | * | |
183 | * This however results in two special cases: | |
184 | * | |
185 | * - removing the last event from a task ctx; this is relatively straight | |
186 | * forward and is done in __perf_remove_from_context. | |
187 | * | |
188 | * - adding the first event to a task ctx; this is tricky because we cannot | |
189 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
190 | * See perf_install_in_context(). | |
191 | * | |
39a43640 PZ |
192 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
193 | */ | |
194 | ||
fae3fde6 PZ |
195 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
196 | struct perf_event_context *, void *); | |
197 | ||
198 | struct event_function_struct { | |
199 | struct perf_event *event; | |
200 | event_f func; | |
201 | void *data; | |
202 | }; | |
203 | ||
204 | static int event_function(void *info) | |
205 | { | |
206 | struct event_function_struct *efs = info; | |
207 | struct perf_event *event = efs->event; | |
0017960f | 208 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
209 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
210 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 211 | int ret = 0; |
fae3fde6 | 212 | |
16444645 | 213 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 214 | |
63b6da39 | 215 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
216 | /* |
217 | * Since we do the IPI call without holding ctx->lock things can have | |
218 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
219 | */ |
220 | if (ctx->task) { | |
63b6da39 | 221 | if (ctx->task != current) { |
0da4cf3e | 222 | ret = -ESRCH; |
63b6da39 PZ |
223 | goto unlock; |
224 | } | |
fae3fde6 | 225 | |
fae3fde6 PZ |
226 | /* |
227 | * We only use event_function_call() on established contexts, | |
228 | * and event_function() is only ever called when active (or | |
229 | * rather, we'll have bailed in task_function_call() or the | |
230 | * above ctx->task != current test), therefore we must have | |
231 | * ctx->is_active here. | |
232 | */ | |
233 | WARN_ON_ONCE(!ctx->is_active); | |
234 | /* | |
235 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
236 | * match. | |
237 | */ | |
63b6da39 PZ |
238 | WARN_ON_ONCE(task_ctx != ctx); |
239 | } else { | |
240 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 241 | } |
63b6da39 | 242 | |
fae3fde6 | 243 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 244 | unlock: |
fae3fde6 PZ |
245 | perf_ctx_unlock(cpuctx, task_ctx); |
246 | ||
63b6da39 | 247 | return ret; |
fae3fde6 PZ |
248 | } |
249 | ||
fae3fde6 | 250 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
251 | { |
252 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 253 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
254 | struct event_function_struct efs = { |
255 | .event = event, | |
256 | .func = func, | |
257 | .data = data, | |
258 | }; | |
0017960f | 259 | |
c97f4736 PZ |
260 | if (!event->parent) { |
261 | /* | |
262 | * If this is a !child event, we must hold ctx::mutex to | |
263 | * stabilize the the event->ctx relation. See | |
264 | * perf_event_ctx_lock(). | |
265 | */ | |
266 | lockdep_assert_held(&ctx->mutex); | |
267 | } | |
0017960f PZ |
268 | |
269 | if (!task) { | |
fae3fde6 | 270 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
271 | return; |
272 | } | |
273 | ||
63b6da39 PZ |
274 | if (task == TASK_TOMBSTONE) |
275 | return; | |
276 | ||
a096309b | 277 | again: |
fae3fde6 | 278 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
279 | return; |
280 | ||
281 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
282 | /* |
283 | * Reload the task pointer, it might have been changed by | |
284 | * a concurrent perf_event_context_sched_out(). | |
285 | */ | |
286 | task = ctx->task; | |
a096309b PZ |
287 | if (task == TASK_TOMBSTONE) { |
288 | raw_spin_unlock_irq(&ctx->lock); | |
289 | return; | |
0017960f | 290 | } |
a096309b PZ |
291 | if (ctx->is_active) { |
292 | raw_spin_unlock_irq(&ctx->lock); | |
293 | goto again; | |
294 | } | |
295 | func(event, NULL, ctx, data); | |
0017960f PZ |
296 | raw_spin_unlock_irq(&ctx->lock); |
297 | } | |
298 | ||
cca20946 PZ |
299 | /* |
300 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
301 | * are already disabled and we're on the right CPU. | |
302 | */ | |
303 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
304 | { | |
305 | struct perf_event_context *ctx = event->ctx; | |
306 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
307 | struct task_struct *task = READ_ONCE(ctx->task); | |
308 | struct perf_event_context *task_ctx = NULL; | |
309 | ||
16444645 | 310 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
311 | |
312 | if (task) { | |
313 | if (task == TASK_TOMBSTONE) | |
314 | return; | |
315 | ||
316 | task_ctx = ctx; | |
317 | } | |
318 | ||
319 | perf_ctx_lock(cpuctx, task_ctx); | |
320 | ||
321 | task = ctx->task; | |
322 | if (task == TASK_TOMBSTONE) | |
323 | goto unlock; | |
324 | ||
325 | if (task) { | |
326 | /* | |
327 | * We must be either inactive or active and the right task, | |
328 | * otherwise we're screwed, since we cannot IPI to somewhere | |
329 | * else. | |
330 | */ | |
331 | if (ctx->is_active) { | |
332 | if (WARN_ON_ONCE(task != current)) | |
333 | goto unlock; | |
334 | ||
335 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
336 | goto unlock; | |
337 | } | |
338 | } else { | |
339 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
340 | } | |
341 | ||
342 | func(event, cpuctx, ctx, data); | |
343 | unlock: | |
344 | perf_ctx_unlock(cpuctx, task_ctx); | |
345 | } | |
346 | ||
e5d1367f SE |
347 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
348 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
349 | PERF_FLAG_PID_CGROUP |\ |
350 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 351 | |
bce38cd5 SE |
352 | /* |
353 | * branch priv levels that need permission checks | |
354 | */ | |
355 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
356 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
357 | PERF_SAMPLE_BRANCH_HV) | |
358 | ||
0b3fcf17 SE |
359 | enum event_type_t { |
360 | EVENT_FLEXIBLE = 0x1, | |
361 | EVENT_PINNED = 0x2, | |
3cbaa590 | 362 | EVENT_TIME = 0x4, |
487f05e1 AS |
363 | /* see ctx_resched() for details */ |
364 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
365 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
366 | }; | |
367 | ||
e5d1367f SE |
368 | /* |
369 | * perf_sched_events : >0 events exist | |
370 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
371 | */ | |
9107c89e PZ |
372 | |
373 | static void perf_sched_delayed(struct work_struct *work); | |
374 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
375 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
376 | static DEFINE_MUTEX(perf_sched_mutex); | |
377 | static atomic_t perf_sched_count; | |
378 | ||
e5d1367f | 379 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 380 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 381 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 382 | |
cdd6c482 IM |
383 | static atomic_t nr_mmap_events __read_mostly; |
384 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 385 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 386 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 387 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 388 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 389 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 390 | static atomic_t nr_bpf_events __read_mostly; |
96aaab68 | 391 | static atomic_t nr_cgroup_events __read_mostly; |
9ee318a7 | 392 | |
108b02cf PZ |
393 | static LIST_HEAD(pmus); |
394 | static DEFINE_MUTEX(pmus_lock); | |
395 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 396 | static cpumask_var_t perf_online_mask; |
108b02cf | 397 | |
0764771d | 398 | /* |
cdd6c482 | 399 | * perf event paranoia level: |
0fbdea19 IM |
400 | * -1 - not paranoid at all |
401 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 402 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 403 | * 2 - disallow kernel profiling for unpriv |
0764771d | 404 | */ |
0161028b | 405 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 406 | |
20443384 FW |
407 | /* Minimum for 512 kiB + 1 user control page */ |
408 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
409 | |
410 | /* | |
cdd6c482 | 411 | * max perf event sample rate |
df58ab24 | 412 | */ |
14c63f17 DH |
413 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
414 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
415 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
416 | ||
417 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
418 | ||
419 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
420 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
421 | ||
d9494cb4 PZ |
422 | static int perf_sample_allowed_ns __read_mostly = |
423 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 424 | |
18ab2cd3 | 425 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
426 | { |
427 | u64 tmp = perf_sample_period_ns; | |
428 | ||
429 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
430 | tmp = div_u64(tmp, 100); |
431 | if (!tmp) | |
432 | tmp = 1; | |
433 | ||
434 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 435 | } |
163ec435 | 436 | |
8d5bce0c | 437 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 438 | |
163ec435 PZ |
439 | int perf_proc_update_handler(struct ctl_table *table, int write, |
440 | void __user *buffer, size_t *lenp, | |
441 | loff_t *ppos) | |
442 | { | |
1a51c5da SE |
443 | int ret; |
444 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
445 | /* |
446 | * If throttling is disabled don't allow the write: | |
447 | */ | |
1a51c5da | 448 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
449 | return -EINVAL; |
450 | ||
1a51c5da SE |
451 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
452 | if (ret || !write) | |
453 | return ret; | |
454 | ||
163ec435 | 455 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
456 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
457 | update_perf_cpu_limits(); | |
458 | ||
459 | return 0; | |
460 | } | |
461 | ||
462 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
463 | ||
464 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
465 | void __user *buffer, size_t *lenp, | |
466 | loff_t *ppos) | |
467 | { | |
1572e45a | 468 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
469 | |
470 | if (ret || !write) | |
471 | return ret; | |
472 | ||
b303e7c1 PZ |
473 | if (sysctl_perf_cpu_time_max_percent == 100 || |
474 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
475 | printk(KERN_WARNING |
476 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
477 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
478 | } else { | |
479 | update_perf_cpu_limits(); | |
480 | } | |
163ec435 PZ |
481 | |
482 | return 0; | |
483 | } | |
1ccd1549 | 484 | |
14c63f17 DH |
485 | /* |
486 | * perf samples are done in some very critical code paths (NMIs). | |
487 | * If they take too much CPU time, the system can lock up and not | |
488 | * get any real work done. This will drop the sample rate when | |
489 | * we detect that events are taking too long. | |
490 | */ | |
491 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 492 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 493 | |
91a612ee PZ |
494 | static u64 __report_avg; |
495 | static u64 __report_allowed; | |
496 | ||
6a02ad66 | 497 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 498 | { |
0d87d7ec | 499 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
500 | "perf: interrupt took too long (%lld > %lld), lowering " |
501 | "kernel.perf_event_max_sample_rate to %d\n", | |
502 | __report_avg, __report_allowed, | |
503 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
504 | } |
505 | ||
506 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
507 | ||
508 | void perf_sample_event_took(u64 sample_len_ns) | |
509 | { | |
91a612ee PZ |
510 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
511 | u64 running_len; | |
512 | u64 avg_len; | |
513 | u32 max; | |
14c63f17 | 514 | |
91a612ee | 515 | if (max_len == 0) |
14c63f17 DH |
516 | return; |
517 | ||
91a612ee PZ |
518 | /* Decay the counter by 1 average sample. */ |
519 | running_len = __this_cpu_read(running_sample_length); | |
520 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
521 | running_len += sample_len_ns; | |
522 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
523 | |
524 | /* | |
91a612ee PZ |
525 | * Note: this will be biased artifically low until we have |
526 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
527 | * from having to maintain a count. |
528 | */ | |
91a612ee PZ |
529 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
530 | if (avg_len <= max_len) | |
14c63f17 DH |
531 | return; |
532 | ||
91a612ee PZ |
533 | __report_avg = avg_len; |
534 | __report_allowed = max_len; | |
14c63f17 | 535 | |
91a612ee PZ |
536 | /* |
537 | * Compute a throttle threshold 25% below the current duration. | |
538 | */ | |
539 | avg_len += avg_len / 4; | |
540 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
541 | if (avg_len < max) | |
542 | max /= (u32)avg_len; | |
543 | else | |
544 | max = 1; | |
14c63f17 | 545 | |
91a612ee PZ |
546 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
547 | WRITE_ONCE(max_samples_per_tick, max); | |
548 | ||
549 | sysctl_perf_event_sample_rate = max * HZ; | |
550 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 551 | |
cd578abb | 552 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 553 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 554 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 555 | __report_avg, __report_allowed, |
cd578abb PZ |
556 | sysctl_perf_event_sample_rate); |
557 | } | |
14c63f17 DH |
558 | } |
559 | ||
cdd6c482 | 560 | static atomic64_t perf_event_id; |
a96bbc16 | 561 | |
0b3fcf17 SE |
562 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
563 | enum event_type_t event_type); | |
564 | ||
565 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
566 | enum event_type_t event_type, |
567 | struct task_struct *task); | |
568 | ||
569 | static void update_context_time(struct perf_event_context *ctx); | |
570 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 571 | |
cdd6c482 | 572 | void __weak perf_event_print_debug(void) { } |
0793a61d | 573 | |
84c79910 | 574 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 575 | { |
84c79910 | 576 | return "pmu"; |
0793a61d TG |
577 | } |
578 | ||
0b3fcf17 SE |
579 | static inline u64 perf_clock(void) |
580 | { | |
581 | return local_clock(); | |
582 | } | |
583 | ||
34f43927 PZ |
584 | static inline u64 perf_event_clock(struct perf_event *event) |
585 | { | |
586 | return event->clock(); | |
587 | } | |
588 | ||
0d3d73aa PZ |
589 | /* |
590 | * State based event timekeeping... | |
591 | * | |
592 | * The basic idea is to use event->state to determine which (if any) time | |
593 | * fields to increment with the current delta. This means we only need to | |
594 | * update timestamps when we change state or when they are explicitly requested | |
595 | * (read). | |
596 | * | |
597 | * Event groups make things a little more complicated, but not terribly so. The | |
598 | * rules for a group are that if the group leader is OFF the entire group is | |
599 | * OFF, irrespecive of what the group member states are. This results in | |
600 | * __perf_effective_state(). | |
601 | * | |
602 | * A futher ramification is that when a group leader flips between OFF and | |
603 | * !OFF, we need to update all group member times. | |
604 | * | |
605 | * | |
606 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
607 | * need to make sure the relevant context time is updated before we try and | |
608 | * update our timestamps. | |
609 | */ | |
610 | ||
611 | static __always_inline enum perf_event_state | |
612 | __perf_effective_state(struct perf_event *event) | |
613 | { | |
614 | struct perf_event *leader = event->group_leader; | |
615 | ||
616 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
617 | return leader->state; | |
618 | ||
619 | return event->state; | |
620 | } | |
621 | ||
622 | static __always_inline void | |
623 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
624 | { | |
625 | enum perf_event_state state = __perf_effective_state(event); | |
626 | u64 delta = now - event->tstamp; | |
627 | ||
628 | *enabled = event->total_time_enabled; | |
629 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
630 | *enabled += delta; | |
631 | ||
632 | *running = event->total_time_running; | |
633 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
634 | *running += delta; | |
635 | } | |
636 | ||
637 | static void perf_event_update_time(struct perf_event *event) | |
638 | { | |
639 | u64 now = perf_event_time(event); | |
640 | ||
641 | __perf_update_times(event, now, &event->total_time_enabled, | |
642 | &event->total_time_running); | |
643 | event->tstamp = now; | |
644 | } | |
645 | ||
646 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
647 | { | |
648 | struct perf_event *sibling; | |
649 | ||
edb39592 | 650 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
651 | perf_event_update_time(sibling); |
652 | } | |
653 | ||
654 | static void | |
655 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
656 | { | |
657 | if (event->state == state) | |
658 | return; | |
659 | ||
660 | perf_event_update_time(event); | |
661 | /* | |
662 | * If a group leader gets enabled/disabled all its siblings | |
663 | * are affected too. | |
664 | */ | |
665 | if ((event->state < 0) ^ (state < 0)) | |
666 | perf_event_update_sibling_time(event); | |
667 | ||
668 | WRITE_ONCE(event->state, state); | |
669 | } | |
670 | ||
e5d1367f SE |
671 | #ifdef CONFIG_CGROUP_PERF |
672 | ||
e5d1367f SE |
673 | static inline bool |
674 | perf_cgroup_match(struct perf_event *event) | |
675 | { | |
676 | struct perf_event_context *ctx = event->ctx; | |
677 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
678 | ||
ef824fa1 TH |
679 | /* @event doesn't care about cgroup */ |
680 | if (!event->cgrp) | |
681 | return true; | |
682 | ||
683 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
684 | if (!cpuctx->cgrp) | |
685 | return false; | |
686 | ||
687 | /* | |
688 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
689 | * also enabled for all its descendant cgroups. If @cpuctx's | |
690 | * cgroup is a descendant of @event's (the test covers identity | |
691 | * case), it's a match. | |
692 | */ | |
693 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
694 | event->cgrp->css.cgroup); | |
e5d1367f SE |
695 | } |
696 | ||
e5d1367f SE |
697 | static inline void perf_detach_cgroup(struct perf_event *event) |
698 | { | |
4e2ba650 | 699 | css_put(&event->cgrp->css); |
e5d1367f SE |
700 | event->cgrp = NULL; |
701 | } | |
702 | ||
703 | static inline int is_cgroup_event(struct perf_event *event) | |
704 | { | |
705 | return event->cgrp != NULL; | |
706 | } | |
707 | ||
708 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
709 | { | |
710 | struct perf_cgroup_info *t; | |
711 | ||
712 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
713 | return t->time; | |
714 | } | |
715 | ||
716 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
717 | { | |
718 | struct perf_cgroup_info *info; | |
719 | u64 now; | |
720 | ||
721 | now = perf_clock(); | |
722 | ||
723 | info = this_cpu_ptr(cgrp->info); | |
724 | ||
725 | info->time += now - info->timestamp; | |
726 | info->timestamp = now; | |
727 | } | |
728 | ||
729 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
730 | { | |
c917e0f2 SL |
731 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
732 | struct cgroup_subsys_state *css; | |
733 | ||
734 | if (cgrp) { | |
735 | for (css = &cgrp->css; css; css = css->parent) { | |
736 | cgrp = container_of(css, struct perf_cgroup, css); | |
737 | __update_cgrp_time(cgrp); | |
738 | } | |
739 | } | |
e5d1367f SE |
740 | } |
741 | ||
742 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
743 | { | |
3f7cce3c SE |
744 | struct perf_cgroup *cgrp; |
745 | ||
e5d1367f | 746 | /* |
3f7cce3c SE |
747 | * ensure we access cgroup data only when needed and |
748 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 749 | */ |
3f7cce3c | 750 | if (!is_cgroup_event(event)) |
e5d1367f SE |
751 | return; |
752 | ||
614e4c4e | 753 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
754 | /* |
755 | * Do not update time when cgroup is not active | |
756 | */ | |
28fa741c | 757 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 758 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
759 | } |
760 | ||
761 | static inline void | |
3f7cce3c SE |
762 | perf_cgroup_set_timestamp(struct task_struct *task, |
763 | struct perf_event_context *ctx) | |
e5d1367f SE |
764 | { |
765 | struct perf_cgroup *cgrp; | |
766 | struct perf_cgroup_info *info; | |
c917e0f2 | 767 | struct cgroup_subsys_state *css; |
e5d1367f | 768 | |
3f7cce3c SE |
769 | /* |
770 | * ctx->lock held by caller | |
771 | * ensure we do not access cgroup data | |
772 | * unless we have the cgroup pinned (css_get) | |
773 | */ | |
774 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
775 | return; |
776 | ||
614e4c4e | 777 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
778 | |
779 | for (css = &cgrp->css; css; css = css->parent) { | |
780 | cgrp = container_of(css, struct perf_cgroup, css); | |
781 | info = this_cpu_ptr(cgrp->info); | |
782 | info->timestamp = ctx->timestamp; | |
783 | } | |
e5d1367f SE |
784 | } |
785 | ||
058fe1c0 DCC |
786 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
787 | ||
e5d1367f SE |
788 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
789 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
790 | ||
791 | /* | |
792 | * reschedule events based on the cgroup constraint of task. | |
793 | * | |
794 | * mode SWOUT : schedule out everything | |
795 | * mode SWIN : schedule in based on cgroup for next | |
796 | */ | |
18ab2cd3 | 797 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
798 | { |
799 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 800 | struct list_head *list; |
e5d1367f SE |
801 | unsigned long flags; |
802 | ||
803 | /* | |
058fe1c0 DCC |
804 | * Disable interrupts and preemption to avoid this CPU's |
805 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
806 | */ |
807 | local_irq_save(flags); | |
808 | ||
058fe1c0 DCC |
809 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
810 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
811 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 812 | |
058fe1c0 DCC |
813 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
814 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 815 | |
058fe1c0 DCC |
816 | if (mode & PERF_CGROUP_SWOUT) { |
817 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
818 | /* | |
819 | * must not be done before ctxswout due | |
820 | * to event_filter_match() in event_sched_out() | |
821 | */ | |
822 | cpuctx->cgrp = NULL; | |
823 | } | |
e5d1367f | 824 | |
058fe1c0 DCC |
825 | if (mode & PERF_CGROUP_SWIN) { |
826 | WARN_ON_ONCE(cpuctx->cgrp); | |
827 | /* | |
828 | * set cgrp before ctxsw in to allow | |
829 | * event_filter_match() to not have to pass | |
830 | * task around | |
831 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
832 | * because cgorup events are only per-cpu | |
833 | */ | |
834 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
835 | &cpuctx->ctx); | |
836 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 837 | } |
058fe1c0 DCC |
838 | perf_pmu_enable(cpuctx->ctx.pmu); |
839 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
840 | } |
841 | ||
e5d1367f SE |
842 | local_irq_restore(flags); |
843 | } | |
844 | ||
a8d757ef SE |
845 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
846 | struct task_struct *next) | |
e5d1367f | 847 | { |
a8d757ef SE |
848 | struct perf_cgroup *cgrp1; |
849 | struct perf_cgroup *cgrp2 = NULL; | |
850 | ||
ddaaf4e2 | 851 | rcu_read_lock(); |
a8d757ef SE |
852 | /* |
853 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
854 | * we do not need to pass the ctx here because we know |
855 | * we are holding the rcu lock | |
a8d757ef | 856 | */ |
614e4c4e | 857 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 858 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
859 | |
860 | /* | |
861 | * only schedule out current cgroup events if we know | |
862 | * that we are switching to a different cgroup. Otherwise, | |
863 | * do no touch the cgroup events. | |
864 | */ | |
865 | if (cgrp1 != cgrp2) | |
866 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
867 | |
868 | rcu_read_unlock(); | |
e5d1367f SE |
869 | } |
870 | ||
a8d757ef SE |
871 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
872 | struct task_struct *task) | |
e5d1367f | 873 | { |
a8d757ef SE |
874 | struct perf_cgroup *cgrp1; |
875 | struct perf_cgroup *cgrp2 = NULL; | |
876 | ||
ddaaf4e2 | 877 | rcu_read_lock(); |
a8d757ef SE |
878 | /* |
879 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
880 | * we do not need to pass the ctx here because we know |
881 | * we are holding the rcu lock | |
a8d757ef | 882 | */ |
614e4c4e | 883 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 884 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
885 | |
886 | /* | |
887 | * only need to schedule in cgroup events if we are changing | |
888 | * cgroup during ctxsw. Cgroup events were not scheduled | |
889 | * out of ctxsw out if that was not the case. | |
890 | */ | |
891 | if (cgrp1 != cgrp2) | |
892 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
893 | |
894 | rcu_read_unlock(); | |
e5d1367f SE |
895 | } |
896 | ||
c2283c93 IR |
897 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
898 | struct cgroup_subsys_state *css) | |
899 | { | |
900 | struct perf_cpu_context *cpuctx; | |
901 | struct perf_event **storage; | |
902 | int cpu, heap_size, ret = 0; | |
903 | ||
904 | /* | |
905 | * Allow storage to have sufficent space for an iterator for each | |
906 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
907 | */ | |
908 | for (heap_size = 1; css; css = css->parent) | |
909 | heap_size++; | |
910 | ||
911 | for_each_possible_cpu(cpu) { | |
912 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
913 | if (heap_size <= cpuctx->heap_size) | |
914 | continue; | |
915 | ||
916 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
917 | GFP_KERNEL, cpu_to_node(cpu)); | |
918 | if (!storage) { | |
919 | ret = -ENOMEM; | |
920 | break; | |
921 | } | |
922 | ||
923 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
924 | if (cpuctx->heap_size < heap_size) { | |
925 | swap(cpuctx->heap, storage); | |
926 | if (storage == cpuctx->heap_default) | |
927 | storage = NULL; | |
928 | cpuctx->heap_size = heap_size; | |
929 | } | |
930 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
931 | ||
932 | kfree(storage); | |
933 | } | |
934 | ||
935 | return ret; | |
936 | } | |
937 | ||
e5d1367f SE |
938 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
939 | struct perf_event_attr *attr, | |
940 | struct perf_event *group_leader) | |
941 | { | |
942 | struct perf_cgroup *cgrp; | |
943 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
944 | struct fd f = fdget(fd); |
945 | int ret = 0; | |
e5d1367f | 946 | |
2903ff01 | 947 | if (!f.file) |
e5d1367f SE |
948 | return -EBADF; |
949 | ||
b583043e | 950 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 951 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
952 | if (IS_ERR(css)) { |
953 | ret = PTR_ERR(css); | |
954 | goto out; | |
955 | } | |
e5d1367f | 956 | |
c2283c93 IR |
957 | ret = perf_cgroup_ensure_storage(event, css); |
958 | if (ret) | |
959 | goto out; | |
960 | ||
e5d1367f SE |
961 | cgrp = container_of(css, struct perf_cgroup, css); |
962 | event->cgrp = cgrp; | |
963 | ||
964 | /* | |
965 | * all events in a group must monitor | |
966 | * the same cgroup because a task belongs | |
967 | * to only one perf cgroup at a time | |
968 | */ | |
969 | if (group_leader && group_leader->cgrp != cgrp) { | |
970 | perf_detach_cgroup(event); | |
971 | ret = -EINVAL; | |
e5d1367f | 972 | } |
3db272c0 | 973 | out: |
2903ff01 | 974 | fdput(f); |
e5d1367f SE |
975 | return ret; |
976 | } | |
977 | ||
978 | static inline void | |
979 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
980 | { | |
981 | struct perf_cgroup_info *t; | |
982 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
983 | event->shadow_ctx_time = now - t->timestamp; | |
984 | } | |
985 | ||
db4a8356 | 986 | static inline void |
33238c50 | 987 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
988 | { |
989 | struct perf_cpu_context *cpuctx; | |
990 | ||
991 | if (!is_cgroup_event(event)) | |
992 | return; | |
993 | ||
db4a8356 DCC |
994 | /* |
995 | * Because cgroup events are always per-cpu events, | |
07c59729 | 996 | * @ctx == &cpuctx->ctx. |
db4a8356 | 997 | */ |
07c59729 | 998 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 999 | |
1000 | /* | |
1001 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1002 | * matching the event's cgroup, we must do this for every new event, | |
1003 | * because if the first would mismatch, the second would not try again | |
1004 | * and we would leave cpuctx->cgrp unset. | |
1005 | */ | |
33238c50 | 1006 | if (ctx->is_active && !cpuctx->cgrp) { |
be96b316 TH |
1007 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1008 | ||
be96b316 TH |
1009 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1010 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1011 | } |
33801b94 | 1012 | |
33238c50 | 1013 | if (ctx->nr_cgroups++) |
33801b94 | 1014 | return; |
33238c50 PZ |
1015 | |
1016 | list_add(&cpuctx->cgrp_cpuctx_entry, | |
1017 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
1018 | } | |
1019 | ||
1020 | static inline void | |
1021 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1022 | { | |
1023 | struct perf_cpu_context *cpuctx; | |
1024 | ||
1025 | if (!is_cgroup_event(event)) | |
33801b94 | 1026 | return; |
1027 | ||
33238c50 PZ |
1028 | /* |
1029 | * Because cgroup events are always per-cpu events, | |
1030 | * @ctx == &cpuctx->ctx. | |
1031 | */ | |
1032 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); | |
1033 | ||
1034 | if (--ctx->nr_cgroups) | |
1035 | return; | |
1036 | ||
1037 | if (ctx->is_active && cpuctx->cgrp) | |
33801b94 | 1038 | cpuctx->cgrp = NULL; |
1039 | ||
33238c50 | 1040 | list_del(&cpuctx->cgrp_cpuctx_entry); |
db4a8356 DCC |
1041 | } |
1042 | ||
e5d1367f SE |
1043 | #else /* !CONFIG_CGROUP_PERF */ |
1044 | ||
1045 | static inline bool | |
1046 | perf_cgroup_match(struct perf_event *event) | |
1047 | { | |
1048 | return true; | |
1049 | } | |
1050 | ||
1051 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1052 | {} | |
1053 | ||
1054 | static inline int is_cgroup_event(struct perf_event *event) | |
1055 | { | |
1056 | return 0; | |
1057 | } | |
1058 | ||
e5d1367f SE |
1059 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1060 | { | |
1061 | } | |
1062 | ||
1063 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1064 | { | |
1065 | } | |
1066 | ||
a8d757ef SE |
1067 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1068 | struct task_struct *next) | |
e5d1367f SE |
1069 | { |
1070 | } | |
1071 | ||
a8d757ef SE |
1072 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1073 | struct task_struct *task) | |
e5d1367f SE |
1074 | { |
1075 | } | |
1076 | ||
1077 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1078 | struct perf_event_attr *attr, | |
1079 | struct perf_event *group_leader) | |
1080 | { | |
1081 | return -EINVAL; | |
1082 | } | |
1083 | ||
1084 | static inline void | |
3f7cce3c SE |
1085 | perf_cgroup_set_timestamp(struct task_struct *task, |
1086 | struct perf_event_context *ctx) | |
e5d1367f SE |
1087 | { |
1088 | } | |
1089 | ||
d00dbd29 | 1090 | static inline void |
e5d1367f SE |
1091 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1092 | { | |
1093 | } | |
1094 | ||
1095 | static inline void | |
1096 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1097 | { | |
1098 | } | |
1099 | ||
1100 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1101 | { | |
1102 | return 0; | |
1103 | } | |
1104 | ||
db4a8356 | 1105 | static inline void |
33238c50 | 1106 | perf_cgroup_event_enable(struct perf_event *event, struct perf_event_context *ctx) |
db4a8356 DCC |
1107 | { |
1108 | } | |
1109 | ||
33238c50 PZ |
1110 | static inline void |
1111 | perf_cgroup_event_disable(struct perf_event *event, struct perf_event_context *ctx) | |
1112 | { | |
1113 | } | |
e5d1367f SE |
1114 | #endif |
1115 | ||
9e630205 SE |
1116 | /* |
1117 | * set default to be dependent on timer tick just | |
1118 | * like original code | |
1119 | */ | |
1120 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1121 | /* | |
8a1115ff | 1122 | * function must be called with interrupts disabled |
9e630205 | 1123 | */ |
272325c4 | 1124 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1125 | { |
1126 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1127 | bool rotations; |
9e630205 | 1128 | |
16444645 | 1129 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1130 | |
1131 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1132 | rotations = perf_rotate_context(cpuctx); |
1133 | ||
4cfafd30 PZ |
1134 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1135 | if (rotations) | |
9e630205 | 1136 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1137 | else |
1138 | cpuctx->hrtimer_active = 0; | |
1139 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1140 | |
4cfafd30 | 1141 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1142 | } |
1143 | ||
272325c4 | 1144 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1145 | { |
272325c4 | 1146 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1147 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1148 | u64 interval; |
9e630205 SE |
1149 | |
1150 | /* no multiplexing needed for SW PMU */ | |
1151 | if (pmu->task_ctx_nr == perf_sw_context) | |
1152 | return; | |
1153 | ||
62b85639 SE |
1154 | /* |
1155 | * check default is sane, if not set then force to | |
1156 | * default interval (1/tick) | |
1157 | */ | |
272325c4 PZ |
1158 | interval = pmu->hrtimer_interval_ms; |
1159 | if (interval < 1) | |
1160 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1161 | |
272325c4 | 1162 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1163 | |
4cfafd30 | 1164 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1165 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1166 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1167 | } |
1168 | ||
272325c4 | 1169 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1170 | { |
272325c4 | 1171 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1172 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1173 | unsigned long flags; |
9e630205 SE |
1174 | |
1175 | /* not for SW PMU */ | |
1176 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1177 | return 0; |
9e630205 | 1178 | |
4cfafd30 PZ |
1179 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1180 | if (!cpuctx->hrtimer_active) { | |
1181 | cpuctx->hrtimer_active = 1; | |
1182 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1183 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1184 | } |
1185 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1186 | |
272325c4 | 1187 | return 0; |
9e630205 SE |
1188 | } |
1189 | ||
33696fc0 | 1190 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1191 | { |
33696fc0 PZ |
1192 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1193 | if (!(*count)++) | |
1194 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1195 | } |
9e35ad38 | 1196 | |
33696fc0 | 1197 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1198 | { |
33696fc0 PZ |
1199 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1200 | if (!--(*count)) | |
1201 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1202 | } |
9e35ad38 | 1203 | |
2fde4f94 | 1204 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1205 | |
1206 | /* | |
2fde4f94 MR |
1207 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1208 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1209 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1210 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1211 | */ |
2fde4f94 | 1212 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1213 | { |
2fde4f94 | 1214 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1215 | |
16444645 | 1216 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1217 | |
2fde4f94 MR |
1218 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1219 | ||
1220 | list_add(&ctx->active_ctx_list, head); | |
1221 | } | |
1222 | ||
1223 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1224 | { | |
16444645 | 1225 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1226 | |
1227 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1228 | ||
1229 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1230 | } |
9e35ad38 | 1231 | |
cdd6c482 | 1232 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1233 | { |
8c94abbb | 1234 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1235 | } |
1236 | ||
4af57ef2 YZ |
1237 | static void free_ctx(struct rcu_head *head) |
1238 | { | |
1239 | struct perf_event_context *ctx; | |
1240 | ||
1241 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1242 | kfree(ctx->task_ctx_data); | |
1243 | kfree(ctx); | |
1244 | } | |
1245 | ||
cdd6c482 | 1246 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1247 | { |
8c94abbb | 1248 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1249 | if (ctx->parent_ctx) |
1250 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1251 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1252 | put_task_struct(ctx->task); |
4af57ef2 | 1253 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1254 | } |
a63eaf34 PM |
1255 | } |
1256 | ||
f63a8daa PZ |
1257 | /* |
1258 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1259 | * perf_pmu_migrate_context() we need some magic. | |
1260 | * | |
1261 | * Those places that change perf_event::ctx will hold both | |
1262 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1263 | * | |
8b10c5e2 PZ |
1264 | * Lock ordering is by mutex address. There are two other sites where |
1265 | * perf_event_context::mutex nests and those are: | |
1266 | * | |
1267 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1268 | * perf_event_exit_event() |
1269 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1270 | * |
1271 | * - perf_event_init_context() [ parent, 0 ] | |
1272 | * inherit_task_group() | |
1273 | * inherit_group() | |
1274 | * inherit_event() | |
1275 | * perf_event_alloc() | |
1276 | * perf_init_event() | |
1277 | * perf_try_init_event() [ child , 1 ] | |
1278 | * | |
1279 | * While it appears there is an obvious deadlock here -- the parent and child | |
1280 | * nesting levels are inverted between the two. This is in fact safe because | |
1281 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1282 | * spawning task cannot (yet) exit. | |
1283 | * | |
1284 | * But remember that that these are parent<->child context relations, and | |
1285 | * migration does not affect children, therefore these two orderings should not | |
1286 | * interact. | |
f63a8daa PZ |
1287 | * |
1288 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1289 | * because the sys_perf_event_open() case will install a new event and break | |
1290 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1291 | * concerned with cpuctx and that doesn't have children. | |
1292 | * | |
1293 | * The places that change perf_event::ctx will issue: | |
1294 | * | |
1295 | * perf_remove_from_context(); | |
1296 | * synchronize_rcu(); | |
1297 | * perf_install_in_context(); | |
1298 | * | |
1299 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1300 | * quiesce the event, after which we can install it in the new location. This | |
1301 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1302 | * while in transit. Therefore all such accessors should also acquire | |
1303 | * perf_event_context::mutex to serialize against this. | |
1304 | * | |
1305 | * However; because event->ctx can change while we're waiting to acquire | |
1306 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1307 | * function. | |
1308 | * | |
1309 | * Lock order: | |
69143038 | 1310 | * exec_update_mutex |
f63a8daa PZ |
1311 | * task_struct::perf_event_mutex |
1312 | * perf_event_context::mutex | |
f63a8daa | 1313 | * perf_event::child_mutex; |
07c4a776 | 1314 | * perf_event_context::lock |
f63a8daa PZ |
1315 | * perf_event::mmap_mutex |
1316 | * mmap_sem | |
18736eef | 1317 | * perf_addr_filters_head::lock |
82d94856 PZ |
1318 | * |
1319 | * cpu_hotplug_lock | |
1320 | * pmus_lock | |
1321 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1322 | */ |
a83fe28e PZ |
1323 | static struct perf_event_context * |
1324 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1325 | { |
1326 | struct perf_event_context *ctx; | |
1327 | ||
1328 | again: | |
1329 | rcu_read_lock(); | |
6aa7de05 | 1330 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1331 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1332 | rcu_read_unlock(); |
1333 | goto again; | |
1334 | } | |
1335 | rcu_read_unlock(); | |
1336 | ||
a83fe28e | 1337 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1338 | if (event->ctx != ctx) { |
1339 | mutex_unlock(&ctx->mutex); | |
1340 | put_ctx(ctx); | |
1341 | goto again; | |
1342 | } | |
1343 | ||
1344 | return ctx; | |
1345 | } | |
1346 | ||
a83fe28e PZ |
1347 | static inline struct perf_event_context * |
1348 | perf_event_ctx_lock(struct perf_event *event) | |
1349 | { | |
1350 | return perf_event_ctx_lock_nested(event, 0); | |
1351 | } | |
1352 | ||
f63a8daa PZ |
1353 | static void perf_event_ctx_unlock(struct perf_event *event, |
1354 | struct perf_event_context *ctx) | |
1355 | { | |
1356 | mutex_unlock(&ctx->mutex); | |
1357 | put_ctx(ctx); | |
1358 | } | |
1359 | ||
211de6eb PZ |
1360 | /* |
1361 | * This must be done under the ctx->lock, such as to serialize against | |
1362 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1363 | * calling scheduler related locks and ctx->lock nests inside those. | |
1364 | */ | |
1365 | static __must_check struct perf_event_context * | |
1366 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1367 | { |
211de6eb PZ |
1368 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1369 | ||
1370 | lockdep_assert_held(&ctx->lock); | |
1371 | ||
1372 | if (parent_ctx) | |
71a851b4 | 1373 | ctx->parent_ctx = NULL; |
5a3126d4 | 1374 | ctx->generation++; |
211de6eb PZ |
1375 | |
1376 | return parent_ctx; | |
71a851b4 PZ |
1377 | } |
1378 | ||
1d953111 ON |
1379 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1380 | enum pid_type type) | |
6844c09d | 1381 | { |
1d953111 | 1382 | u32 nr; |
6844c09d ACM |
1383 | /* |
1384 | * only top level events have the pid namespace they were created in | |
1385 | */ | |
1386 | if (event->parent) | |
1387 | event = event->parent; | |
1388 | ||
1d953111 ON |
1389 | nr = __task_pid_nr_ns(p, type, event->ns); |
1390 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1391 | if (!nr && !pid_alive(p)) | |
1392 | nr = -1; | |
1393 | return nr; | |
6844c09d ACM |
1394 | } |
1395 | ||
1d953111 | 1396 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1397 | { |
6883f81a | 1398 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1399 | } |
6844c09d | 1400 | |
1d953111 ON |
1401 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1402 | { | |
1403 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1404 | } |
1405 | ||
7f453c24 | 1406 | /* |
cdd6c482 | 1407 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1408 | * to userspace. |
1409 | */ | |
cdd6c482 | 1410 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1411 | { |
cdd6c482 | 1412 | u64 id = event->id; |
7f453c24 | 1413 | |
cdd6c482 IM |
1414 | if (event->parent) |
1415 | id = event->parent->id; | |
7f453c24 PZ |
1416 | |
1417 | return id; | |
1418 | } | |
1419 | ||
25346b93 | 1420 | /* |
cdd6c482 | 1421 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1422 | * |
25346b93 PM |
1423 | * This has to cope with with the fact that until it is locked, |
1424 | * the context could get moved to another task. | |
1425 | */ | |
cdd6c482 | 1426 | static struct perf_event_context * |
8dc85d54 | 1427 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1428 | { |
cdd6c482 | 1429 | struct perf_event_context *ctx; |
25346b93 | 1430 | |
9ed6060d | 1431 | retry: |
058ebd0e PZ |
1432 | /* |
1433 | * One of the few rules of preemptible RCU is that one cannot do | |
1434 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1435 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1436 | * rcu_read_unlock_special(). |
1437 | * | |
1438 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1439 | * side critical section has interrupts disabled. |
058ebd0e | 1440 | */ |
2fd59077 | 1441 | local_irq_save(*flags); |
058ebd0e | 1442 | rcu_read_lock(); |
8dc85d54 | 1443 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1444 | if (ctx) { |
1445 | /* | |
1446 | * If this context is a clone of another, it might | |
1447 | * get swapped for another underneath us by | |
cdd6c482 | 1448 | * perf_event_task_sched_out, though the |
25346b93 PM |
1449 | * rcu_read_lock() protects us from any context |
1450 | * getting freed. Lock the context and check if it | |
1451 | * got swapped before we could get the lock, and retry | |
1452 | * if so. If we locked the right context, then it | |
1453 | * can't get swapped on us any more. | |
1454 | */ | |
2fd59077 | 1455 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1456 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1457 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1458 | rcu_read_unlock(); |
2fd59077 | 1459 | local_irq_restore(*flags); |
25346b93 PM |
1460 | goto retry; |
1461 | } | |
b49a9e7e | 1462 | |
63b6da39 | 1463 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1464 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1465 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1466 | ctx = NULL; |
828b6f0e PZ |
1467 | } else { |
1468 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1469 | } |
25346b93 PM |
1470 | } |
1471 | rcu_read_unlock(); | |
2fd59077 PM |
1472 | if (!ctx) |
1473 | local_irq_restore(*flags); | |
25346b93 PM |
1474 | return ctx; |
1475 | } | |
1476 | ||
1477 | /* | |
1478 | * Get the context for a task and increment its pin_count so it | |
1479 | * can't get swapped to another task. This also increments its | |
1480 | * reference count so that the context can't get freed. | |
1481 | */ | |
8dc85d54 PZ |
1482 | static struct perf_event_context * |
1483 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1484 | { |
cdd6c482 | 1485 | struct perf_event_context *ctx; |
25346b93 PM |
1486 | unsigned long flags; |
1487 | ||
8dc85d54 | 1488 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1489 | if (ctx) { |
1490 | ++ctx->pin_count; | |
e625cce1 | 1491 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1492 | } |
1493 | return ctx; | |
1494 | } | |
1495 | ||
cdd6c482 | 1496 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1497 | { |
1498 | unsigned long flags; | |
1499 | ||
e625cce1 | 1500 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1501 | --ctx->pin_count; |
e625cce1 | 1502 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1503 | } |
1504 | ||
f67218c3 PZ |
1505 | /* |
1506 | * Update the record of the current time in a context. | |
1507 | */ | |
1508 | static void update_context_time(struct perf_event_context *ctx) | |
1509 | { | |
1510 | u64 now = perf_clock(); | |
1511 | ||
1512 | ctx->time += now - ctx->timestamp; | |
1513 | ctx->timestamp = now; | |
1514 | } | |
1515 | ||
4158755d SE |
1516 | static u64 perf_event_time(struct perf_event *event) |
1517 | { | |
1518 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1519 | |
1520 | if (is_cgroup_event(event)) | |
1521 | return perf_cgroup_event_time(event); | |
1522 | ||
4158755d SE |
1523 | return ctx ? ctx->time : 0; |
1524 | } | |
1525 | ||
487f05e1 AS |
1526 | static enum event_type_t get_event_type(struct perf_event *event) |
1527 | { | |
1528 | struct perf_event_context *ctx = event->ctx; | |
1529 | enum event_type_t event_type; | |
1530 | ||
1531 | lockdep_assert_held(&ctx->lock); | |
1532 | ||
3bda69c1 AS |
1533 | /* |
1534 | * It's 'group type', really, because if our group leader is | |
1535 | * pinned, so are we. | |
1536 | */ | |
1537 | if (event->group_leader != event) | |
1538 | event = event->group_leader; | |
1539 | ||
487f05e1 AS |
1540 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1541 | if (!ctx->task) | |
1542 | event_type |= EVENT_CPU; | |
1543 | ||
1544 | return event_type; | |
1545 | } | |
1546 | ||
8e1a2031 | 1547 | /* |
161c85fa | 1548 | * Helper function to initialize event group nodes. |
8e1a2031 | 1549 | */ |
161c85fa | 1550 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1551 | { |
1552 | RB_CLEAR_NODE(&event->group_node); | |
1553 | event->group_index = 0; | |
1554 | } | |
1555 | ||
1556 | /* | |
1557 | * Extract pinned or flexible groups from the context | |
161c85fa | 1558 | * based on event attrs bits. |
8e1a2031 AB |
1559 | */ |
1560 | static struct perf_event_groups * | |
1561 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1562 | { |
1563 | if (event->attr.pinned) | |
1564 | return &ctx->pinned_groups; | |
1565 | else | |
1566 | return &ctx->flexible_groups; | |
1567 | } | |
1568 | ||
8e1a2031 | 1569 | /* |
161c85fa | 1570 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1571 | */ |
161c85fa | 1572 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1573 | { |
1574 | groups->tree = RB_ROOT; | |
1575 | groups->index = 0; | |
1576 | } | |
1577 | ||
1578 | /* | |
1579 | * Compare function for event groups; | |
161c85fa PZ |
1580 | * |
1581 | * Implements complex key that first sorts by CPU and then by virtual index | |
1582 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1583 | */ |
161c85fa PZ |
1584 | static bool |
1585 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1586 | { |
161c85fa PZ |
1587 | if (left->cpu < right->cpu) |
1588 | return true; | |
1589 | if (left->cpu > right->cpu) | |
1590 | return false; | |
1591 | ||
95ed6c70 IR |
1592 | #ifdef CONFIG_CGROUP_PERF |
1593 | if (left->cgrp != right->cgrp) { | |
1594 | if (!left->cgrp || !left->cgrp->css.cgroup) { | |
1595 | /* | |
1596 | * Left has no cgroup but right does, no cgroups come | |
1597 | * first. | |
1598 | */ | |
1599 | return true; | |
1600 | } | |
a6763625 | 1601 | if (!right->cgrp || !right->cgrp->css.cgroup) { |
95ed6c70 IR |
1602 | /* |
1603 | * Right has no cgroup but left does, no cgroups come | |
1604 | * first. | |
1605 | */ | |
1606 | return false; | |
1607 | } | |
1608 | /* Two dissimilar cgroups, order by id. */ | |
1609 | if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) | |
1610 | return true; | |
1611 | ||
1612 | return false; | |
1613 | } | |
1614 | #endif | |
1615 | ||
161c85fa PZ |
1616 | if (left->group_index < right->group_index) |
1617 | return true; | |
1618 | if (left->group_index > right->group_index) | |
1619 | return false; | |
1620 | ||
1621 | return false; | |
8e1a2031 AB |
1622 | } |
1623 | ||
1624 | /* | |
161c85fa PZ |
1625 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1626 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1627 | * subtree. | |
8e1a2031 AB |
1628 | */ |
1629 | static void | |
1630 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1631 | struct perf_event *event) |
8e1a2031 AB |
1632 | { |
1633 | struct perf_event *node_event; | |
1634 | struct rb_node *parent; | |
1635 | struct rb_node **node; | |
1636 | ||
1637 | event->group_index = ++groups->index; | |
1638 | ||
1639 | node = &groups->tree.rb_node; | |
1640 | parent = *node; | |
1641 | ||
1642 | while (*node) { | |
1643 | parent = *node; | |
161c85fa | 1644 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1645 | |
1646 | if (perf_event_groups_less(event, node_event)) | |
1647 | node = &parent->rb_left; | |
1648 | else | |
1649 | node = &parent->rb_right; | |
1650 | } | |
1651 | ||
1652 | rb_link_node(&event->group_node, parent, node); | |
1653 | rb_insert_color(&event->group_node, &groups->tree); | |
1654 | } | |
1655 | ||
1656 | /* | |
161c85fa | 1657 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1658 | */ |
1659 | static void | |
1660 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1661 | { | |
1662 | struct perf_event_groups *groups; | |
1663 | ||
1664 | groups = get_event_groups(event, ctx); | |
1665 | perf_event_groups_insert(groups, event); | |
1666 | } | |
1667 | ||
1668 | /* | |
161c85fa | 1669 | * Delete a group from a tree. |
8e1a2031 AB |
1670 | */ |
1671 | static void | |
1672 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1673 | struct perf_event *event) |
8e1a2031 | 1674 | { |
161c85fa PZ |
1675 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1676 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1677 | |
161c85fa | 1678 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1679 | init_event_group(event); |
1680 | } | |
1681 | ||
1682 | /* | |
161c85fa | 1683 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1684 | */ |
1685 | static void | |
1686 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1687 | { | |
1688 | struct perf_event_groups *groups; | |
1689 | ||
1690 | groups = get_event_groups(event, ctx); | |
1691 | perf_event_groups_delete(groups, event); | |
1692 | } | |
1693 | ||
1694 | /* | |
95ed6c70 | 1695 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1696 | */ |
1697 | static struct perf_event * | |
95ed6c70 IR |
1698 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1699 | struct cgroup *cgrp) | |
8e1a2031 AB |
1700 | { |
1701 | struct perf_event *node_event = NULL, *match = NULL; | |
1702 | struct rb_node *node = groups->tree.rb_node; | |
95ed6c70 IR |
1703 | #ifdef CONFIG_CGROUP_PERF |
1704 | u64 node_cgrp_id, cgrp_id = 0; | |
1705 | ||
1706 | if (cgrp) | |
1707 | cgrp_id = cgrp->kn->id; | |
1708 | #endif | |
8e1a2031 AB |
1709 | |
1710 | while (node) { | |
161c85fa | 1711 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1712 | |
1713 | if (cpu < node_event->cpu) { | |
1714 | node = node->rb_left; | |
95ed6c70 IR |
1715 | continue; |
1716 | } | |
1717 | if (cpu > node_event->cpu) { | |
8e1a2031 | 1718 | node = node->rb_right; |
95ed6c70 IR |
1719 | continue; |
1720 | } | |
1721 | #ifdef CONFIG_CGROUP_PERF | |
1722 | node_cgrp_id = 0; | |
1723 | if (node_event->cgrp && node_event->cgrp->css.cgroup) | |
1724 | node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; | |
1725 | ||
1726 | if (cgrp_id < node_cgrp_id) { | |
8e1a2031 | 1727 | node = node->rb_left; |
95ed6c70 IR |
1728 | continue; |
1729 | } | |
1730 | if (cgrp_id > node_cgrp_id) { | |
1731 | node = node->rb_right; | |
1732 | continue; | |
8e1a2031 | 1733 | } |
95ed6c70 IR |
1734 | #endif |
1735 | match = node_event; | |
1736 | node = node->rb_left; | |
8e1a2031 AB |
1737 | } |
1738 | ||
1739 | return match; | |
1740 | } | |
1741 | ||
1cac7b1a PZ |
1742 | /* |
1743 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1744 | */ | |
1745 | static struct perf_event * | |
1746 | perf_event_groups_next(struct perf_event *event) | |
1747 | { | |
1748 | struct perf_event *next; | |
95ed6c70 IR |
1749 | #ifdef CONFIG_CGROUP_PERF |
1750 | u64 curr_cgrp_id = 0; | |
1751 | u64 next_cgrp_id = 0; | |
1752 | #endif | |
1cac7b1a PZ |
1753 | |
1754 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
95ed6c70 IR |
1755 | if (next == NULL || next->cpu != event->cpu) |
1756 | return NULL; | |
1757 | ||
1758 | #ifdef CONFIG_CGROUP_PERF | |
1759 | if (event->cgrp && event->cgrp->css.cgroup) | |
1760 | curr_cgrp_id = event->cgrp->css.cgroup->kn->id; | |
1cac7b1a | 1761 | |
95ed6c70 IR |
1762 | if (next->cgrp && next->cgrp->css.cgroup) |
1763 | next_cgrp_id = next->cgrp->css.cgroup->kn->id; | |
1764 | ||
1765 | if (curr_cgrp_id != next_cgrp_id) | |
1766 | return NULL; | |
1767 | #endif | |
1768 | return next; | |
1cac7b1a PZ |
1769 | } |
1770 | ||
8e1a2031 | 1771 | /* |
161c85fa | 1772 | * Iterate through the whole groups tree. |
8e1a2031 | 1773 | */ |
6e6804d2 PZ |
1774 | #define perf_event_groups_for_each(event, groups) \ |
1775 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1776 | typeof(*event), group_node); event; \ | |
1777 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1778 | typeof(*event), group_node)) | |
8e1a2031 | 1779 | |
fccc714b | 1780 | /* |
788faab7 | 1781 | * Add an event from the lists for its context. |
fccc714b PZ |
1782 | * Must be called with ctx->mutex and ctx->lock held. |
1783 | */ | |
04289bb9 | 1784 | static void |
cdd6c482 | 1785 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1786 | { |
c994d613 PZ |
1787 | lockdep_assert_held(&ctx->lock); |
1788 | ||
8a49542c PZ |
1789 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1790 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1791 | |
0d3d73aa PZ |
1792 | event->tstamp = perf_event_time(event); |
1793 | ||
04289bb9 | 1794 | /* |
8a49542c PZ |
1795 | * If we're a stand alone event or group leader, we go to the context |
1796 | * list, group events are kept attached to the group so that | |
1797 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1798 | */ |
8a49542c | 1799 | if (event->group_leader == event) { |
4ff6a8de | 1800 | event->group_caps = event->event_caps; |
8e1a2031 | 1801 | add_event_to_groups(event, ctx); |
5c148194 | 1802 | } |
592903cd | 1803 | |
cdd6c482 IM |
1804 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1805 | ctx->nr_events++; | |
1806 | if (event->attr.inherit_stat) | |
bfbd3381 | 1807 | ctx->nr_stat++; |
5a3126d4 | 1808 | |
33238c50 PZ |
1809 | if (event->state > PERF_EVENT_STATE_OFF) |
1810 | perf_cgroup_event_enable(event, ctx); | |
1811 | ||
5a3126d4 | 1812 | ctx->generation++; |
04289bb9 IM |
1813 | } |
1814 | ||
0231bb53 JO |
1815 | /* |
1816 | * Initialize event state based on the perf_event_attr::disabled. | |
1817 | */ | |
1818 | static inline void perf_event__state_init(struct perf_event *event) | |
1819 | { | |
1820 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1821 | PERF_EVENT_STATE_INACTIVE; | |
1822 | } | |
1823 | ||
a723968c | 1824 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1825 | { |
1826 | int entry = sizeof(u64); /* value */ | |
1827 | int size = 0; | |
1828 | int nr = 1; | |
1829 | ||
1830 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1831 | size += sizeof(u64); | |
1832 | ||
1833 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1834 | size += sizeof(u64); | |
1835 | ||
1836 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1837 | entry += sizeof(u64); | |
1838 | ||
1839 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1840 | nr += nr_siblings; |
c320c7b7 ACM |
1841 | size += sizeof(u64); |
1842 | } | |
1843 | ||
1844 | size += entry * nr; | |
1845 | event->read_size = size; | |
1846 | } | |
1847 | ||
a723968c | 1848 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1849 | { |
1850 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1851 | u16 size = 0; |
1852 | ||
c320c7b7 ACM |
1853 | if (sample_type & PERF_SAMPLE_IP) |
1854 | size += sizeof(data->ip); | |
1855 | ||
6844c09d ACM |
1856 | if (sample_type & PERF_SAMPLE_ADDR) |
1857 | size += sizeof(data->addr); | |
1858 | ||
1859 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1860 | size += sizeof(data->period); | |
1861 | ||
c3feedf2 AK |
1862 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1863 | size += sizeof(data->weight); | |
1864 | ||
6844c09d ACM |
1865 | if (sample_type & PERF_SAMPLE_READ) |
1866 | size += event->read_size; | |
1867 | ||
d6be9ad6 SE |
1868 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1869 | size += sizeof(data->data_src.val); | |
1870 | ||
fdfbbd07 AK |
1871 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1872 | size += sizeof(data->txn); | |
1873 | ||
fc7ce9c7 KL |
1874 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1875 | size += sizeof(data->phys_addr); | |
1876 | ||
6546b19f NK |
1877 | if (sample_type & PERF_SAMPLE_CGROUP) |
1878 | size += sizeof(data->cgroup); | |
1879 | ||
6844c09d ACM |
1880 | event->header_size = size; |
1881 | } | |
1882 | ||
a723968c PZ |
1883 | /* |
1884 | * Called at perf_event creation and when events are attached/detached from a | |
1885 | * group. | |
1886 | */ | |
1887 | static void perf_event__header_size(struct perf_event *event) | |
1888 | { | |
1889 | __perf_event_read_size(event, | |
1890 | event->group_leader->nr_siblings); | |
1891 | __perf_event_header_size(event, event->attr.sample_type); | |
1892 | } | |
1893 | ||
6844c09d ACM |
1894 | static void perf_event__id_header_size(struct perf_event *event) |
1895 | { | |
1896 | struct perf_sample_data *data; | |
1897 | u64 sample_type = event->attr.sample_type; | |
1898 | u16 size = 0; | |
1899 | ||
c320c7b7 ACM |
1900 | if (sample_type & PERF_SAMPLE_TID) |
1901 | size += sizeof(data->tid_entry); | |
1902 | ||
1903 | if (sample_type & PERF_SAMPLE_TIME) | |
1904 | size += sizeof(data->time); | |
1905 | ||
ff3d527c AH |
1906 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1907 | size += sizeof(data->id); | |
1908 | ||
c320c7b7 ACM |
1909 | if (sample_type & PERF_SAMPLE_ID) |
1910 | size += sizeof(data->id); | |
1911 | ||
1912 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1913 | size += sizeof(data->stream_id); | |
1914 | ||
1915 | if (sample_type & PERF_SAMPLE_CPU) | |
1916 | size += sizeof(data->cpu_entry); | |
1917 | ||
6844c09d | 1918 | event->id_header_size = size; |
c320c7b7 ACM |
1919 | } |
1920 | ||
a723968c PZ |
1921 | static bool perf_event_validate_size(struct perf_event *event) |
1922 | { | |
1923 | /* | |
1924 | * The values computed here will be over-written when we actually | |
1925 | * attach the event. | |
1926 | */ | |
1927 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1928 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1929 | perf_event__id_header_size(event); | |
1930 | ||
1931 | /* | |
1932 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1933 | * Conservative limit to allow for callchains and other variable fields. | |
1934 | */ | |
1935 | if (event->read_size + event->header_size + | |
1936 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1937 | return false; | |
1938 | ||
1939 | return true; | |
1940 | } | |
1941 | ||
8a49542c PZ |
1942 | static void perf_group_attach(struct perf_event *event) |
1943 | { | |
c320c7b7 | 1944 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1945 | |
a76a82a3 PZ |
1946 | lockdep_assert_held(&event->ctx->lock); |
1947 | ||
74c3337c PZ |
1948 | /* |
1949 | * We can have double attach due to group movement in perf_event_open. | |
1950 | */ | |
1951 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1952 | return; | |
1953 | ||
8a49542c PZ |
1954 | event->attach_state |= PERF_ATTACH_GROUP; |
1955 | ||
1956 | if (group_leader == event) | |
1957 | return; | |
1958 | ||
652884fe PZ |
1959 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1960 | ||
4ff6a8de | 1961 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1962 | |
8343aae6 | 1963 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1964 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1965 | |
1966 | perf_event__header_size(group_leader); | |
1967 | ||
edb39592 | 1968 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1969 | perf_event__header_size(pos); |
8a49542c PZ |
1970 | } |
1971 | ||
a63eaf34 | 1972 | /* |
788faab7 | 1973 | * Remove an event from the lists for its context. |
fccc714b | 1974 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1975 | */ |
04289bb9 | 1976 | static void |
cdd6c482 | 1977 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1978 | { |
652884fe PZ |
1979 | WARN_ON_ONCE(event->ctx != ctx); |
1980 | lockdep_assert_held(&ctx->lock); | |
1981 | ||
8a49542c PZ |
1982 | /* |
1983 | * We can have double detach due to exit/hot-unplug + close. | |
1984 | */ | |
1985 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1986 | return; |
8a49542c PZ |
1987 | |
1988 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1989 | ||
cdd6c482 IM |
1990 | ctx->nr_events--; |
1991 | if (event->attr.inherit_stat) | |
bfbd3381 | 1992 | ctx->nr_stat--; |
8bc20959 | 1993 | |
cdd6c482 | 1994 | list_del_rcu(&event->event_entry); |
04289bb9 | 1995 | |
8a49542c | 1996 | if (event->group_leader == event) |
8e1a2031 | 1997 | del_event_from_groups(event, ctx); |
5c148194 | 1998 | |
b2e74a26 SE |
1999 | /* |
2000 | * If event was in error state, then keep it | |
2001 | * that way, otherwise bogus counts will be | |
2002 | * returned on read(). The only way to get out | |
2003 | * of error state is by explicit re-enabling | |
2004 | * of the event | |
2005 | */ | |
33238c50 PZ |
2006 | if (event->state > PERF_EVENT_STATE_OFF) { |
2007 | perf_cgroup_event_disable(event, ctx); | |
0d3d73aa | 2008 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
33238c50 | 2009 | } |
5a3126d4 PZ |
2010 | |
2011 | ctx->generation++; | |
050735b0 PZ |
2012 | } |
2013 | ||
ab43762e AS |
2014 | static int |
2015 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2016 | { | |
2017 | if (!has_aux(aux_event)) | |
2018 | return 0; | |
2019 | ||
2020 | if (!event->pmu->aux_output_match) | |
2021 | return 0; | |
2022 | ||
2023 | return event->pmu->aux_output_match(aux_event); | |
2024 | } | |
2025 | ||
2026 | static void put_event(struct perf_event *event); | |
2027 | static void event_sched_out(struct perf_event *event, | |
2028 | struct perf_cpu_context *cpuctx, | |
2029 | struct perf_event_context *ctx); | |
2030 | ||
2031 | static void perf_put_aux_event(struct perf_event *event) | |
2032 | { | |
2033 | struct perf_event_context *ctx = event->ctx; | |
2034 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2035 | struct perf_event *iter; | |
2036 | ||
2037 | /* | |
2038 | * If event uses aux_event tear down the link | |
2039 | */ | |
2040 | if (event->aux_event) { | |
2041 | iter = event->aux_event; | |
2042 | event->aux_event = NULL; | |
2043 | put_event(iter); | |
2044 | return; | |
2045 | } | |
2046 | ||
2047 | /* | |
2048 | * If the event is an aux_event, tear down all links to | |
2049 | * it from other events. | |
2050 | */ | |
2051 | for_each_sibling_event(iter, event->group_leader) { | |
2052 | if (iter->aux_event != event) | |
2053 | continue; | |
2054 | ||
2055 | iter->aux_event = NULL; | |
2056 | put_event(event); | |
2057 | ||
2058 | /* | |
2059 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2060 | * state so that we don't try to schedule it again. Note | |
2061 | * that perf_event_enable() will clear the ERROR status. | |
2062 | */ | |
2063 | event_sched_out(iter, cpuctx, ctx); | |
2064 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2065 | } | |
2066 | } | |
2067 | ||
a4faf00d AS |
2068 | static bool perf_need_aux_event(struct perf_event *event) |
2069 | { | |
2070 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2071 | } | |
2072 | ||
ab43762e AS |
2073 | static int perf_get_aux_event(struct perf_event *event, |
2074 | struct perf_event *group_leader) | |
2075 | { | |
2076 | /* | |
2077 | * Our group leader must be an aux event if we want to be | |
2078 | * an aux_output. This way, the aux event will precede its | |
2079 | * aux_output events in the group, and therefore will always | |
2080 | * schedule first. | |
2081 | */ | |
2082 | if (!group_leader) | |
2083 | return 0; | |
2084 | ||
a4faf00d AS |
2085 | /* |
2086 | * aux_output and aux_sample_size are mutually exclusive. | |
2087 | */ | |
2088 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2089 | return 0; | |
2090 | ||
2091 | if (event->attr.aux_output && | |
2092 | !perf_aux_output_match(event, group_leader)) | |
2093 | return 0; | |
2094 | ||
2095 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2096 | return 0; |
2097 | ||
2098 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2099 | return 0; | |
2100 | ||
2101 | /* | |
2102 | * Link aux_outputs to their aux event; this is undone in | |
2103 | * perf_group_detach() by perf_put_aux_event(). When the | |
2104 | * group in torn down, the aux_output events loose their | |
2105 | * link to the aux_event and can't schedule any more. | |
2106 | */ | |
2107 | event->aux_event = group_leader; | |
2108 | ||
2109 | return 1; | |
2110 | } | |
2111 | ||
ab6f824c PZ |
2112 | static inline struct list_head *get_event_list(struct perf_event *event) |
2113 | { | |
2114 | struct perf_event_context *ctx = event->ctx; | |
2115 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2116 | } | |
2117 | ||
8a49542c | 2118 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
2119 | { |
2120 | struct perf_event *sibling, *tmp; | |
6668128a | 2121 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2122 | |
6668128a | 2123 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2124 | |
8a49542c PZ |
2125 | /* |
2126 | * We can have double detach due to exit/hot-unplug + close. | |
2127 | */ | |
2128 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2129 | return; | |
2130 | ||
2131 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2132 | ||
ab43762e AS |
2133 | perf_put_aux_event(event); |
2134 | ||
8a49542c PZ |
2135 | /* |
2136 | * If this is a sibling, remove it from its group. | |
2137 | */ | |
2138 | if (event->group_leader != event) { | |
8343aae6 | 2139 | list_del_init(&event->sibling_list); |
8a49542c | 2140 | event->group_leader->nr_siblings--; |
c320c7b7 | 2141 | goto out; |
8a49542c PZ |
2142 | } |
2143 | ||
04289bb9 | 2144 | /* |
cdd6c482 IM |
2145 | * If this was a group event with sibling events then |
2146 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2147 | * to whatever list we are on. |
04289bb9 | 2148 | */ |
8343aae6 | 2149 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2150 | |
04289bb9 | 2151 | sibling->group_leader = sibling; |
24868367 | 2152 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2153 | |
2154 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2155 | sibling->group_caps = event->group_caps; |
652884fe | 2156 | |
8e1a2031 | 2157 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2158 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2159 | |
ab6f824c PZ |
2160 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2161 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2162 | } |
2163 | ||
652884fe | 2164 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2165 | } |
c320c7b7 ACM |
2166 | |
2167 | out: | |
2168 | perf_event__header_size(event->group_leader); | |
2169 | ||
edb39592 | 2170 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 2171 | perf_event__header_size(tmp); |
04289bb9 IM |
2172 | } |
2173 | ||
fadfe7be JO |
2174 | static bool is_orphaned_event(struct perf_event *event) |
2175 | { | |
a69b0ca4 | 2176 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2177 | } |
2178 | ||
2c81a647 | 2179 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2180 | { |
2181 | struct pmu *pmu = event->pmu; | |
2182 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2183 | } | |
2184 | ||
2c81a647 MR |
2185 | /* |
2186 | * Check whether we should attempt to schedule an event group based on | |
2187 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2188 | * potentially with a SW leader, so we must check all the filters, to | |
2189 | * determine whether a group is schedulable: | |
2190 | */ | |
2191 | static inline int pmu_filter_match(struct perf_event *event) | |
2192 | { | |
edb39592 | 2193 | struct perf_event *sibling; |
2c81a647 MR |
2194 | |
2195 | if (!__pmu_filter_match(event)) | |
2196 | return 0; | |
2197 | ||
edb39592 PZ |
2198 | for_each_sibling_event(sibling, event) { |
2199 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2200 | return 0; |
2201 | } | |
2202 | ||
2203 | return 1; | |
2204 | } | |
2205 | ||
fa66f07a SE |
2206 | static inline int |
2207 | event_filter_match(struct perf_event *event) | |
2208 | { | |
0b8f1e2e PZ |
2209 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2210 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2211 | } |
2212 | ||
9ffcfa6f SE |
2213 | static void |
2214 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2215 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2216 | struct perf_event_context *ctx) |
3b6f9e5c | 2217 | { |
0d3d73aa | 2218 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2219 | |
2220 | WARN_ON_ONCE(event->ctx != ctx); | |
2221 | lockdep_assert_held(&ctx->lock); | |
2222 | ||
cdd6c482 | 2223 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2224 | return; |
3b6f9e5c | 2225 | |
6668128a PZ |
2226 | /* |
2227 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2228 | * we can schedule events _OUT_ individually through things like | |
2229 | * __perf_remove_from_context(). | |
2230 | */ | |
2231 | list_del_init(&event->active_list); | |
2232 | ||
44377277 AS |
2233 | perf_pmu_disable(event->pmu); |
2234 | ||
28a967c3 PZ |
2235 | event->pmu->del(event, 0); |
2236 | event->oncpu = -1; | |
0d3d73aa | 2237 | |
1d54ad94 PZ |
2238 | if (READ_ONCE(event->pending_disable) >= 0) { |
2239 | WRITE_ONCE(event->pending_disable, -1); | |
33238c50 | 2240 | perf_cgroup_event_disable(event, ctx); |
0d3d73aa | 2241 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2242 | } |
0d3d73aa | 2243 | perf_event_set_state(event, state); |
3b6f9e5c | 2244 | |
cdd6c482 | 2245 | if (!is_software_event(event)) |
3b6f9e5c | 2246 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2247 | if (!--ctx->nr_active) |
2248 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2249 | if (event->attr.freq && event->attr.sample_freq) |
2250 | ctx->nr_freq--; | |
cdd6c482 | 2251 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2252 | cpuctx->exclusive = 0; |
44377277 AS |
2253 | |
2254 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2255 | } |
2256 | ||
d859e29f | 2257 | static void |
cdd6c482 | 2258 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2259 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2260 | struct perf_event_context *ctx) |
d859e29f | 2261 | { |
cdd6c482 | 2262 | struct perf_event *event; |
0d3d73aa PZ |
2263 | |
2264 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2265 | return; | |
d859e29f | 2266 | |
3f005e7d MR |
2267 | perf_pmu_disable(ctx->pmu); |
2268 | ||
cdd6c482 | 2269 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2270 | |
2271 | /* | |
2272 | * Schedule out siblings (if any): | |
2273 | */ | |
edb39592 | 2274 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2275 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2276 | |
3f005e7d MR |
2277 | perf_pmu_enable(ctx->pmu); |
2278 | ||
0d3d73aa | 2279 | if (group_event->attr.exclusive) |
d859e29f PM |
2280 | cpuctx->exclusive = 0; |
2281 | } | |
2282 | ||
45a0e07a | 2283 | #define DETACH_GROUP 0x01UL |
0017960f | 2284 | |
0793a61d | 2285 | /* |
cdd6c482 | 2286 | * Cross CPU call to remove a performance event |
0793a61d | 2287 | * |
cdd6c482 | 2288 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2289 | * remove it from the context list. |
2290 | */ | |
fae3fde6 PZ |
2291 | static void |
2292 | __perf_remove_from_context(struct perf_event *event, | |
2293 | struct perf_cpu_context *cpuctx, | |
2294 | struct perf_event_context *ctx, | |
2295 | void *info) | |
0793a61d | 2296 | { |
45a0e07a | 2297 | unsigned long flags = (unsigned long)info; |
0793a61d | 2298 | |
3c5c8711 PZ |
2299 | if (ctx->is_active & EVENT_TIME) { |
2300 | update_context_time(ctx); | |
2301 | update_cgrp_time_from_cpuctx(cpuctx); | |
2302 | } | |
2303 | ||
cdd6c482 | 2304 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2305 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2306 | perf_group_detach(event); |
cdd6c482 | 2307 | list_del_event(event, ctx); |
39a43640 PZ |
2308 | |
2309 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2310 | ctx->is_active = 0; |
90c91dfb | 2311 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2312 | if (ctx->task) { |
2313 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2314 | cpuctx->task_ctx = NULL; | |
2315 | } | |
64ce3126 | 2316 | } |
0793a61d TG |
2317 | } |
2318 | ||
0793a61d | 2319 | /* |
cdd6c482 | 2320 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2321 | * |
cdd6c482 IM |
2322 | * If event->ctx is a cloned context, callers must make sure that |
2323 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2324 | * remains valid. This is OK when called from perf_release since |
2325 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2326 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2327 | * context has been detached from its task. |
0793a61d | 2328 | */ |
45a0e07a | 2329 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2330 | { |
a76a82a3 PZ |
2331 | struct perf_event_context *ctx = event->ctx; |
2332 | ||
2333 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2334 | |
45a0e07a | 2335 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2336 | |
2337 | /* | |
2338 | * The above event_function_call() can NO-OP when it hits | |
2339 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2340 | * from the context (by perf_event_exit_event()) but the grouping | |
2341 | * might still be in-tact. | |
2342 | */ | |
2343 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2344 | if ((flags & DETACH_GROUP) && | |
2345 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2346 | /* | |
2347 | * Since in that case we cannot possibly be scheduled, simply | |
2348 | * detach now. | |
2349 | */ | |
2350 | raw_spin_lock_irq(&ctx->lock); | |
2351 | perf_group_detach(event); | |
2352 | raw_spin_unlock_irq(&ctx->lock); | |
2353 | } | |
0793a61d TG |
2354 | } |
2355 | ||
d859e29f | 2356 | /* |
cdd6c482 | 2357 | * Cross CPU call to disable a performance event |
d859e29f | 2358 | */ |
fae3fde6 PZ |
2359 | static void __perf_event_disable(struct perf_event *event, |
2360 | struct perf_cpu_context *cpuctx, | |
2361 | struct perf_event_context *ctx, | |
2362 | void *info) | |
7b648018 | 2363 | { |
fae3fde6 PZ |
2364 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2365 | return; | |
7b648018 | 2366 | |
3c5c8711 PZ |
2367 | if (ctx->is_active & EVENT_TIME) { |
2368 | update_context_time(ctx); | |
2369 | update_cgrp_time_from_event(event); | |
2370 | } | |
2371 | ||
fae3fde6 PZ |
2372 | if (event == event->group_leader) |
2373 | group_sched_out(event, cpuctx, ctx); | |
2374 | else | |
2375 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2376 | |
2377 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
33238c50 | 2378 | perf_cgroup_event_disable(event, ctx); |
7b648018 PZ |
2379 | } |
2380 | ||
d859e29f | 2381 | /* |
788faab7 | 2382 | * Disable an event. |
c93f7669 | 2383 | * |
cdd6c482 IM |
2384 | * If event->ctx is a cloned context, callers must make sure that |
2385 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2386 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2387 | * perf_event_for_each_child or perf_event_for_each because they |
2388 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2389 | * goes to exit will block in perf_event_exit_event(). |
2390 | * | |
cdd6c482 | 2391 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2392 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2393 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2394 | */ |
f63a8daa | 2395 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2396 | { |
cdd6c482 | 2397 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2398 | |
e625cce1 | 2399 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2400 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2401 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2402 | return; |
53cfbf59 | 2403 | } |
e625cce1 | 2404 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2405 | |
fae3fde6 PZ |
2406 | event_function_call(event, __perf_event_disable, NULL); |
2407 | } | |
2408 | ||
2409 | void perf_event_disable_local(struct perf_event *event) | |
2410 | { | |
2411 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2412 | } |
f63a8daa PZ |
2413 | |
2414 | /* | |
2415 | * Strictly speaking kernel users cannot create groups and therefore this | |
2416 | * interface does not need the perf_event_ctx_lock() magic. | |
2417 | */ | |
2418 | void perf_event_disable(struct perf_event *event) | |
2419 | { | |
2420 | struct perf_event_context *ctx; | |
2421 | ||
2422 | ctx = perf_event_ctx_lock(event); | |
2423 | _perf_event_disable(event); | |
2424 | perf_event_ctx_unlock(event, ctx); | |
2425 | } | |
dcfce4a0 | 2426 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2427 | |
5aab90ce JO |
2428 | void perf_event_disable_inatomic(struct perf_event *event) |
2429 | { | |
1d54ad94 PZ |
2430 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2431 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2432 | irq_work_queue(&event->pending); |
2433 | } | |
2434 | ||
e5d1367f | 2435 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2436 | struct perf_event_context *ctx) |
e5d1367f SE |
2437 | { |
2438 | /* | |
2439 | * use the correct time source for the time snapshot | |
2440 | * | |
2441 | * We could get by without this by leveraging the | |
2442 | * fact that to get to this function, the caller | |
2443 | * has most likely already called update_context_time() | |
2444 | * and update_cgrp_time_xx() and thus both timestamp | |
2445 | * are identical (or very close). Given that tstamp is, | |
2446 | * already adjusted for cgroup, we could say that: | |
2447 | * tstamp - ctx->timestamp | |
2448 | * is equivalent to | |
2449 | * tstamp - cgrp->timestamp. | |
2450 | * | |
2451 | * Then, in perf_output_read(), the calculation would | |
2452 | * work with no changes because: | |
2453 | * - event is guaranteed scheduled in | |
2454 | * - no scheduled out in between | |
2455 | * - thus the timestamp would be the same | |
2456 | * | |
2457 | * But this is a bit hairy. | |
2458 | * | |
2459 | * So instead, we have an explicit cgroup call to remain | |
2460 | * within the time time source all along. We believe it | |
2461 | * is cleaner and simpler to understand. | |
2462 | */ | |
2463 | if (is_cgroup_event(event)) | |
0d3d73aa | 2464 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2465 | else |
0d3d73aa | 2466 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2467 | } |
2468 | ||
4fe757dd PZ |
2469 | #define MAX_INTERRUPTS (~0ULL) |
2470 | ||
2471 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2472 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2473 | |
235c7fc7 | 2474 | static int |
9ffcfa6f | 2475 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2476 | struct perf_cpu_context *cpuctx, |
6e37738a | 2477 | struct perf_event_context *ctx) |
235c7fc7 | 2478 | { |
44377277 | 2479 | int ret = 0; |
4158755d | 2480 | |
ab6f824c PZ |
2481 | WARN_ON_ONCE(event->ctx != ctx); |
2482 | ||
63342411 PZ |
2483 | lockdep_assert_held(&ctx->lock); |
2484 | ||
cdd6c482 | 2485 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2486 | return 0; |
2487 | ||
95ff4ca2 AS |
2488 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2489 | /* | |
0c1cbc18 PZ |
2490 | * Order event::oncpu write to happen before the ACTIVE state is |
2491 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2492 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2493 | */ |
2494 | smp_wmb(); | |
0d3d73aa | 2495 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2496 | |
2497 | /* | |
2498 | * Unthrottle events, since we scheduled we might have missed several | |
2499 | * ticks already, also for a heavily scheduling task there is little | |
2500 | * guarantee it'll get a tick in a timely manner. | |
2501 | */ | |
2502 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2503 | perf_log_throttle(event, 1); | |
2504 | event->hw.interrupts = 0; | |
2505 | } | |
2506 | ||
44377277 AS |
2507 | perf_pmu_disable(event->pmu); |
2508 | ||
0d3d73aa | 2509 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2510 | |
ec0d7729 AS |
2511 | perf_log_itrace_start(event); |
2512 | ||
a4eaf7f1 | 2513 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2514 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2515 | event->oncpu = -1; |
44377277 AS |
2516 | ret = -EAGAIN; |
2517 | goto out; | |
235c7fc7 IM |
2518 | } |
2519 | ||
cdd6c482 | 2520 | if (!is_software_event(event)) |
3b6f9e5c | 2521 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2522 | if (!ctx->nr_active++) |
2523 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2524 | if (event->attr.freq && event->attr.sample_freq) |
2525 | ctx->nr_freq++; | |
235c7fc7 | 2526 | |
cdd6c482 | 2527 | if (event->attr.exclusive) |
3b6f9e5c PM |
2528 | cpuctx->exclusive = 1; |
2529 | ||
44377277 AS |
2530 | out: |
2531 | perf_pmu_enable(event->pmu); | |
2532 | ||
2533 | return ret; | |
235c7fc7 IM |
2534 | } |
2535 | ||
6751b71e | 2536 | static int |
cdd6c482 | 2537 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2538 | struct perf_cpu_context *cpuctx, |
6e37738a | 2539 | struct perf_event_context *ctx) |
6751b71e | 2540 | { |
6bde9b6c | 2541 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2542 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2543 | |
cdd6c482 | 2544 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2545 | return 0; |
2546 | ||
fbbe0701 | 2547 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2548 | |
9ffcfa6f | 2549 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2550 | pmu->cancel_txn(pmu); |
272325c4 | 2551 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2552 | return -EAGAIN; |
90151c35 | 2553 | } |
6751b71e PM |
2554 | |
2555 | /* | |
2556 | * Schedule in siblings as one group (if any): | |
2557 | */ | |
edb39592 | 2558 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2559 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2560 | partial_group = event; |
6751b71e PM |
2561 | goto group_error; |
2562 | } | |
2563 | } | |
2564 | ||
9ffcfa6f | 2565 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2566 | return 0; |
9ffcfa6f | 2567 | |
6751b71e PM |
2568 | group_error: |
2569 | /* | |
2570 | * Groups can be scheduled in as one unit only, so undo any | |
2571 | * partial group before returning: | |
0d3d73aa | 2572 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2573 | */ |
edb39592 | 2574 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2575 | if (event == partial_group) |
0d3d73aa | 2576 | break; |
d7842da4 | 2577 | |
0d3d73aa | 2578 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2579 | } |
9ffcfa6f | 2580 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2581 | |
ad5133b7 | 2582 | pmu->cancel_txn(pmu); |
90151c35 | 2583 | |
272325c4 | 2584 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2585 | |
6751b71e PM |
2586 | return -EAGAIN; |
2587 | } | |
2588 | ||
3b6f9e5c | 2589 | /* |
cdd6c482 | 2590 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2591 | */ |
cdd6c482 | 2592 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2593 | struct perf_cpu_context *cpuctx, |
2594 | int can_add_hw) | |
2595 | { | |
2596 | /* | |
cdd6c482 | 2597 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2598 | */ |
4ff6a8de | 2599 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2600 | return 1; |
2601 | /* | |
2602 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2603 | * events can go on. |
3b6f9e5c PM |
2604 | */ |
2605 | if (cpuctx->exclusive) | |
2606 | return 0; | |
2607 | /* | |
2608 | * If this group is exclusive and there are already | |
cdd6c482 | 2609 | * events on the CPU, it can't go on. |
3b6f9e5c | 2610 | */ |
cdd6c482 | 2611 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2612 | return 0; |
2613 | /* | |
2614 | * Otherwise, try to add it if all previous groups were able | |
2615 | * to go on. | |
2616 | */ | |
2617 | return can_add_hw; | |
2618 | } | |
2619 | ||
cdd6c482 IM |
2620 | static void add_event_to_ctx(struct perf_event *event, |
2621 | struct perf_event_context *ctx) | |
53cfbf59 | 2622 | { |
cdd6c482 | 2623 | list_add_event(event, ctx); |
8a49542c | 2624 | perf_group_attach(event); |
53cfbf59 PM |
2625 | } |
2626 | ||
bd2afa49 PZ |
2627 | static void ctx_sched_out(struct perf_event_context *ctx, |
2628 | struct perf_cpu_context *cpuctx, | |
2629 | enum event_type_t event_type); | |
2c29ef0f PZ |
2630 | static void |
2631 | ctx_sched_in(struct perf_event_context *ctx, | |
2632 | struct perf_cpu_context *cpuctx, | |
2633 | enum event_type_t event_type, | |
2634 | struct task_struct *task); | |
fe4b04fa | 2635 | |
bd2afa49 | 2636 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2637 | struct perf_event_context *ctx, |
2638 | enum event_type_t event_type) | |
bd2afa49 PZ |
2639 | { |
2640 | if (!cpuctx->task_ctx) | |
2641 | return; | |
2642 | ||
2643 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2644 | return; | |
2645 | ||
487f05e1 | 2646 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2647 | } |
2648 | ||
dce5855b PZ |
2649 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2650 | struct perf_event_context *ctx, | |
2651 | struct task_struct *task) | |
2652 | { | |
2653 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2654 | if (ctx) | |
2655 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2656 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2657 | if (ctx) | |
2658 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2659 | } | |
2660 | ||
487f05e1 AS |
2661 | /* |
2662 | * We want to maintain the following priority of scheduling: | |
2663 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2664 | * - task pinned (EVENT_PINNED) | |
2665 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2666 | * - task flexible (EVENT_FLEXIBLE). | |
2667 | * | |
2668 | * In order to avoid unscheduling and scheduling back in everything every | |
2669 | * time an event is added, only do it for the groups of equal priority and | |
2670 | * below. | |
2671 | * | |
2672 | * This can be called after a batch operation on task events, in which case | |
2673 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2674 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2675 | */ | |
3e349507 | 2676 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2677 | struct perf_event_context *task_ctx, |
2678 | enum event_type_t event_type) | |
0017960f | 2679 | { |
bd903afe | 2680 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2681 | bool cpu_event = !!(event_type & EVENT_CPU); |
2682 | ||
2683 | /* | |
2684 | * If pinned groups are involved, flexible groups also need to be | |
2685 | * scheduled out. | |
2686 | */ | |
2687 | if (event_type & EVENT_PINNED) | |
2688 | event_type |= EVENT_FLEXIBLE; | |
2689 | ||
bd903afe SL |
2690 | ctx_event_type = event_type & EVENT_ALL; |
2691 | ||
3e349507 PZ |
2692 | perf_pmu_disable(cpuctx->ctx.pmu); |
2693 | if (task_ctx) | |
487f05e1 AS |
2694 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2695 | ||
2696 | /* | |
2697 | * Decide which cpu ctx groups to schedule out based on the types | |
2698 | * of events that caused rescheduling: | |
2699 | * - EVENT_CPU: schedule out corresponding groups; | |
2700 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2701 | * - otherwise, do nothing more. | |
2702 | */ | |
2703 | if (cpu_event) | |
2704 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2705 | else if (ctx_event_type & EVENT_PINNED) | |
2706 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2707 | ||
3e349507 PZ |
2708 | perf_event_sched_in(cpuctx, task_ctx, current); |
2709 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2710 | } |
2711 | ||
c68d224e SE |
2712 | void perf_pmu_resched(struct pmu *pmu) |
2713 | { | |
2714 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2715 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2716 | ||
2717 | perf_ctx_lock(cpuctx, task_ctx); | |
2718 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2719 | perf_ctx_unlock(cpuctx, task_ctx); | |
2720 | } | |
2721 | ||
0793a61d | 2722 | /* |
cdd6c482 | 2723 | * Cross CPU call to install and enable a performance event |
682076ae | 2724 | * |
a096309b PZ |
2725 | * Very similar to remote_function() + event_function() but cannot assume that |
2726 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2727 | */ |
fe4b04fa | 2728 | static int __perf_install_in_context(void *info) |
0793a61d | 2729 | { |
a096309b PZ |
2730 | struct perf_event *event = info; |
2731 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2732 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2733 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2734 | bool reprogram = true; |
a096309b | 2735 | int ret = 0; |
0793a61d | 2736 | |
63b6da39 | 2737 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2738 | if (ctx->task) { |
b58f6b0d PZ |
2739 | raw_spin_lock(&ctx->lock); |
2740 | task_ctx = ctx; | |
a096309b | 2741 | |
63cae12b | 2742 | reprogram = (ctx->task == current); |
b58f6b0d | 2743 | |
39a43640 | 2744 | /* |
63cae12b PZ |
2745 | * If the task is running, it must be running on this CPU, |
2746 | * otherwise we cannot reprogram things. | |
2747 | * | |
2748 | * If its not running, we don't care, ctx->lock will | |
2749 | * serialize against it becoming runnable. | |
39a43640 | 2750 | */ |
63cae12b PZ |
2751 | if (task_curr(ctx->task) && !reprogram) { |
2752 | ret = -ESRCH; | |
2753 | goto unlock; | |
2754 | } | |
a096309b | 2755 | |
63cae12b | 2756 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2757 | } else if (task_ctx) { |
2758 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2759 | } |
b58f6b0d | 2760 | |
33801b94 | 2761 | #ifdef CONFIG_CGROUP_PERF |
33238c50 | 2762 | if (event->state > PERF_EVENT_STATE_OFF && is_cgroup_event(event)) { |
33801b94 | 2763 | /* |
2764 | * If the current cgroup doesn't match the event's | |
2765 | * cgroup, we should not try to schedule it. | |
2766 | */ | |
2767 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2768 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2769 | event->cgrp->css.cgroup); | |
2770 | } | |
2771 | #endif | |
2772 | ||
63cae12b | 2773 | if (reprogram) { |
a096309b PZ |
2774 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2775 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2776 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2777 | } else { |
2778 | add_event_to_ctx(event, ctx); | |
2779 | } | |
2780 | ||
63b6da39 | 2781 | unlock: |
2c29ef0f | 2782 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2783 | |
a096309b | 2784 | return ret; |
0793a61d TG |
2785 | } |
2786 | ||
8a58ddae AS |
2787 | static bool exclusive_event_installable(struct perf_event *event, |
2788 | struct perf_event_context *ctx); | |
2789 | ||
0793a61d | 2790 | /* |
a096309b PZ |
2791 | * Attach a performance event to a context. |
2792 | * | |
2793 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2794 | */ |
2795 | static void | |
cdd6c482 IM |
2796 | perf_install_in_context(struct perf_event_context *ctx, |
2797 | struct perf_event *event, | |
0793a61d TG |
2798 | int cpu) |
2799 | { | |
a096309b | 2800 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2801 | |
fe4b04fa PZ |
2802 | lockdep_assert_held(&ctx->mutex); |
2803 | ||
8a58ddae AS |
2804 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2805 | ||
0cda4c02 YZ |
2806 | if (event->cpu != -1) |
2807 | event->cpu = cpu; | |
c3f00c70 | 2808 | |
0b8f1e2e PZ |
2809 | /* |
2810 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2811 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2812 | */ | |
2813 | smp_store_release(&event->ctx, ctx); | |
2814 | ||
db0503e4 PZ |
2815 | /* |
2816 | * perf_event_attr::disabled events will not run and can be initialized | |
2817 | * without IPI. Except when this is the first event for the context, in | |
2818 | * that case we need the magic of the IPI to set ctx->is_active. | |
2819 | * | |
2820 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2821 | * event will issue the IPI and reprogram the hardware. | |
2822 | */ | |
2823 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2824 | raw_spin_lock_irq(&ctx->lock); | |
2825 | if (ctx->task == TASK_TOMBSTONE) { | |
2826 | raw_spin_unlock_irq(&ctx->lock); | |
2827 | return; | |
2828 | } | |
2829 | add_event_to_ctx(event, ctx); | |
2830 | raw_spin_unlock_irq(&ctx->lock); | |
2831 | return; | |
2832 | } | |
2833 | ||
a096309b PZ |
2834 | if (!task) { |
2835 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2836 | return; | |
2837 | } | |
2838 | ||
2839 | /* | |
2840 | * Should not happen, we validate the ctx is still alive before calling. | |
2841 | */ | |
2842 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2843 | return; | |
2844 | ||
39a43640 PZ |
2845 | /* |
2846 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2847 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2848 | * |
2849 | * Instead we use task_curr(), which tells us if the task is running. | |
2850 | * However, since we use task_curr() outside of rq::lock, we can race | |
2851 | * against the actual state. This means the result can be wrong. | |
2852 | * | |
2853 | * If we get a false positive, we retry, this is harmless. | |
2854 | * | |
2855 | * If we get a false negative, things are complicated. If we are after | |
2856 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2857 | * value must be correct. If we're before, it doesn't matter since | |
2858 | * perf_event_context_sched_in() will program the counter. | |
2859 | * | |
2860 | * However, this hinges on the remote context switch having observed | |
2861 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2862 | * ctx::lock in perf_event_context_sched_in(). | |
2863 | * | |
2864 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2865 | * we know any future context switch of task must see the | |
2866 | * perf_event_ctpx[] store. | |
39a43640 | 2867 | */ |
63cae12b | 2868 | |
63b6da39 | 2869 | /* |
63cae12b PZ |
2870 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2871 | * task_cpu() load, such that if the IPI then does not find the task | |
2872 | * running, a future context switch of that task must observe the | |
2873 | * store. | |
63b6da39 | 2874 | */ |
63cae12b PZ |
2875 | smp_mb(); |
2876 | again: | |
2877 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2878 | return; |
2879 | ||
2880 | raw_spin_lock_irq(&ctx->lock); | |
2881 | task = ctx->task; | |
84c4e620 | 2882 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2883 | /* |
2884 | * Cannot happen because we already checked above (which also | |
2885 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2886 | * against perf_event_exit_task_context(). | |
2887 | */ | |
63b6da39 PZ |
2888 | raw_spin_unlock_irq(&ctx->lock); |
2889 | return; | |
2890 | } | |
39a43640 | 2891 | /* |
63cae12b PZ |
2892 | * If the task is not running, ctx->lock will avoid it becoming so, |
2893 | * thus we can safely install the event. | |
39a43640 | 2894 | */ |
63cae12b PZ |
2895 | if (task_curr(task)) { |
2896 | raw_spin_unlock_irq(&ctx->lock); | |
2897 | goto again; | |
2898 | } | |
2899 | add_event_to_ctx(event, ctx); | |
2900 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2901 | } |
2902 | ||
d859e29f | 2903 | /* |
cdd6c482 | 2904 | * Cross CPU call to enable a performance event |
d859e29f | 2905 | */ |
fae3fde6 PZ |
2906 | static void __perf_event_enable(struct perf_event *event, |
2907 | struct perf_cpu_context *cpuctx, | |
2908 | struct perf_event_context *ctx, | |
2909 | void *info) | |
04289bb9 | 2910 | { |
cdd6c482 | 2911 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2912 | struct perf_event_context *task_ctx; |
04289bb9 | 2913 | |
6e801e01 PZ |
2914 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2915 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2916 | return; |
3cbed429 | 2917 | |
bd2afa49 PZ |
2918 | if (ctx->is_active) |
2919 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2920 | ||
0d3d73aa | 2921 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
33238c50 | 2922 | perf_cgroup_event_enable(event, ctx); |
04289bb9 | 2923 | |
fae3fde6 PZ |
2924 | if (!ctx->is_active) |
2925 | return; | |
2926 | ||
e5d1367f | 2927 | if (!event_filter_match(event)) { |
bd2afa49 | 2928 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2929 | return; |
e5d1367f | 2930 | } |
f4c4176f | 2931 | |
04289bb9 | 2932 | /* |
cdd6c482 | 2933 | * If the event is in a group and isn't the group leader, |
d859e29f | 2934 | * then don't put it on unless the group is on. |
04289bb9 | 2935 | */ |
bd2afa49 PZ |
2936 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2937 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2938 | return; |
bd2afa49 | 2939 | } |
fe4b04fa | 2940 | |
fae3fde6 PZ |
2941 | task_ctx = cpuctx->task_ctx; |
2942 | if (ctx->task) | |
2943 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2944 | |
487f05e1 | 2945 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2946 | } |
2947 | ||
d859e29f | 2948 | /* |
788faab7 | 2949 | * Enable an event. |
c93f7669 | 2950 | * |
cdd6c482 IM |
2951 | * If event->ctx is a cloned context, callers must make sure that |
2952 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2953 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2954 | * perf_event_for_each_child or perf_event_for_each as described |
2955 | * for perf_event_disable. | |
d859e29f | 2956 | */ |
f63a8daa | 2957 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2958 | { |
cdd6c482 | 2959 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2960 | |
7b648018 | 2961 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2962 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2963 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2964 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2965 | return; |
2966 | } | |
2967 | ||
d859e29f | 2968 | /* |
cdd6c482 | 2969 | * If the event is in error state, clear that first. |
7b648018 PZ |
2970 | * |
2971 | * That way, if we see the event in error state below, we know that it | |
2972 | * has gone back into error state, as distinct from the task having | |
2973 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2974 | */ |
cdd6c482 IM |
2975 | if (event->state == PERF_EVENT_STATE_ERROR) |
2976 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2977 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2978 | |
fae3fde6 | 2979 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2980 | } |
f63a8daa PZ |
2981 | |
2982 | /* | |
2983 | * See perf_event_disable(); | |
2984 | */ | |
2985 | void perf_event_enable(struct perf_event *event) | |
2986 | { | |
2987 | struct perf_event_context *ctx; | |
2988 | ||
2989 | ctx = perf_event_ctx_lock(event); | |
2990 | _perf_event_enable(event); | |
2991 | perf_event_ctx_unlock(event, ctx); | |
2992 | } | |
dcfce4a0 | 2993 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2994 | |
375637bc AS |
2995 | struct stop_event_data { |
2996 | struct perf_event *event; | |
2997 | unsigned int restart; | |
2998 | }; | |
2999 | ||
95ff4ca2 AS |
3000 | static int __perf_event_stop(void *info) |
3001 | { | |
375637bc AS |
3002 | struct stop_event_data *sd = info; |
3003 | struct perf_event *event = sd->event; | |
95ff4ca2 | 3004 | |
375637bc | 3005 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
3006 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
3007 | return 0; | |
3008 | ||
3009 | /* matches smp_wmb() in event_sched_in() */ | |
3010 | smp_rmb(); | |
3011 | ||
3012 | /* | |
3013 | * There is a window with interrupts enabled before we get here, | |
3014 | * so we need to check again lest we try to stop another CPU's event. | |
3015 | */ | |
3016 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
3017 | return -EAGAIN; | |
3018 | ||
3019 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3020 | ||
375637bc AS |
3021 | /* |
3022 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3023 | * but it is only used for events with AUX ring buffer, and such | |
3024 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3025 | * see comments in perf_aux_output_begin(). | |
3026 | * | |
788faab7 | 3027 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3028 | * while restarting. |
3029 | */ | |
3030 | if (sd->restart) | |
c9bbdd48 | 3031 | event->pmu->start(event, 0); |
375637bc | 3032 | |
95ff4ca2 AS |
3033 | return 0; |
3034 | } | |
3035 | ||
767ae086 | 3036 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3037 | { |
3038 | struct stop_event_data sd = { | |
3039 | .event = event, | |
767ae086 | 3040 | .restart = restart, |
375637bc AS |
3041 | }; |
3042 | int ret = 0; | |
3043 | ||
3044 | do { | |
3045 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3046 | return 0; | |
3047 | ||
3048 | /* matches smp_wmb() in event_sched_in() */ | |
3049 | smp_rmb(); | |
3050 | ||
3051 | /* | |
3052 | * We only want to restart ACTIVE events, so if the event goes | |
3053 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3054 | * fall through with ret==-ENXIO. | |
3055 | */ | |
3056 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3057 | __perf_event_stop, &sd); | |
3058 | } while (ret == -EAGAIN); | |
3059 | ||
3060 | return ret; | |
3061 | } | |
3062 | ||
3063 | /* | |
3064 | * In order to contain the amount of racy and tricky in the address filter | |
3065 | * configuration management, it is a two part process: | |
3066 | * | |
3067 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3068 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3069 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3070 | * (p2) when an event is scheduled in (pmu::add), it calls |
3071 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3072 | * if the generation has changed since the previous call. | |
3073 | * | |
3074 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3075 | * | |
3076 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3077 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3078 | * ioctl; | |
3079 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
3080 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
3081 | * for reading; | |
3082 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3083 | * of exec. | |
3084 | */ | |
3085 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3086 | { | |
3087 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3088 | ||
3089 | if (!has_addr_filter(event)) | |
3090 | return; | |
3091 | ||
3092 | raw_spin_lock(&ifh->lock); | |
3093 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3094 | event->pmu->addr_filters_sync(event); | |
3095 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3096 | } | |
3097 | raw_spin_unlock(&ifh->lock); | |
3098 | } | |
3099 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3100 | ||
f63a8daa | 3101 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3102 | { |
2023b359 | 3103 | /* |
cdd6c482 | 3104 | * not supported on inherited events |
2023b359 | 3105 | */ |
2e939d1d | 3106 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3107 | return -EINVAL; |
3108 | ||
cdd6c482 | 3109 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3110 | _perf_event_enable(event); |
2023b359 PZ |
3111 | |
3112 | return 0; | |
79f14641 | 3113 | } |
f63a8daa PZ |
3114 | |
3115 | /* | |
3116 | * See perf_event_disable() | |
3117 | */ | |
3118 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3119 | { | |
3120 | struct perf_event_context *ctx; | |
3121 | int ret; | |
3122 | ||
3123 | ctx = perf_event_ctx_lock(event); | |
3124 | ret = _perf_event_refresh(event, refresh); | |
3125 | perf_event_ctx_unlock(event, ctx); | |
3126 | ||
3127 | return ret; | |
3128 | } | |
26ca5c11 | 3129 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3130 | |
32ff77e8 MC |
3131 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3132 | struct perf_event_attr *attr) | |
3133 | { | |
3134 | int err; | |
3135 | ||
3136 | _perf_event_disable(bp); | |
3137 | ||
3138 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3139 | |
bf06278c | 3140 | if (!bp->attr.disabled) |
32ff77e8 | 3141 | _perf_event_enable(bp); |
bf06278c JO |
3142 | |
3143 | return err; | |
32ff77e8 MC |
3144 | } |
3145 | ||
3146 | static int perf_event_modify_attr(struct perf_event *event, | |
3147 | struct perf_event_attr *attr) | |
3148 | { | |
3149 | if (event->attr.type != attr->type) | |
3150 | return -EINVAL; | |
3151 | ||
3152 | switch (event->attr.type) { | |
3153 | case PERF_TYPE_BREAKPOINT: | |
3154 | return perf_event_modify_breakpoint(event, attr); | |
3155 | default: | |
3156 | /* Place holder for future additions. */ | |
3157 | return -EOPNOTSUPP; | |
3158 | } | |
3159 | } | |
3160 | ||
5b0311e1 FW |
3161 | static void ctx_sched_out(struct perf_event_context *ctx, |
3162 | struct perf_cpu_context *cpuctx, | |
3163 | enum event_type_t event_type) | |
235c7fc7 | 3164 | { |
6668128a | 3165 | struct perf_event *event, *tmp; |
db24d33e | 3166 | int is_active = ctx->is_active; |
235c7fc7 | 3167 | |
c994d613 | 3168 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3169 | |
39a43640 PZ |
3170 | if (likely(!ctx->nr_events)) { |
3171 | /* | |
3172 | * See __perf_remove_from_context(). | |
3173 | */ | |
3174 | WARN_ON_ONCE(ctx->is_active); | |
3175 | if (ctx->task) | |
3176 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3177 | return; |
39a43640 PZ |
3178 | } |
3179 | ||
db24d33e | 3180 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3181 | if (!(ctx->is_active & EVENT_ALL)) |
3182 | ctx->is_active = 0; | |
3183 | ||
63e30d3e PZ |
3184 | if (ctx->task) { |
3185 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3186 | if (!ctx->is_active) | |
3187 | cpuctx->task_ctx = NULL; | |
3188 | } | |
facc4307 | 3189 | |
8fdc6539 PZ |
3190 | /* |
3191 | * Always update time if it was set; not only when it changes. | |
3192 | * Otherwise we can 'forget' to update time for any but the last | |
3193 | * context we sched out. For example: | |
3194 | * | |
3195 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3196 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3197 | * | |
3198 | * would only update time for the pinned events. | |
3199 | */ | |
3cbaa590 PZ |
3200 | if (is_active & EVENT_TIME) { |
3201 | /* update (and stop) ctx time */ | |
3202 | update_context_time(ctx); | |
3203 | update_cgrp_time_from_cpuctx(cpuctx); | |
3204 | } | |
3205 | ||
8fdc6539 PZ |
3206 | is_active ^= ctx->is_active; /* changed bits */ |
3207 | ||
3cbaa590 | 3208 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3209 | return; |
5b0311e1 | 3210 | |
075e0b00 | 3211 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3212 | if (is_active & EVENT_PINNED) { |
6668128a | 3213 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3214 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3215 | } |
889ff015 | 3216 | |
3cbaa590 | 3217 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3218 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3219 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3220 | |
3221 | /* | |
3222 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3223 | * rotate_necessary, is will be reset by | |
3224 | * ctx_flexible_sched_in() when needed. | |
3225 | */ | |
3226 | ctx->rotate_necessary = 0; | |
9ed6060d | 3227 | } |
1b9a644f | 3228 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3229 | } |
3230 | ||
564c2b21 | 3231 | /* |
5a3126d4 PZ |
3232 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3233 | * cloned from the same version of the same context. | |
3234 | * | |
3235 | * Equivalence is measured using a generation number in the context that is | |
3236 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3237 | * and list_del_event(). | |
564c2b21 | 3238 | */ |
cdd6c482 IM |
3239 | static int context_equiv(struct perf_event_context *ctx1, |
3240 | struct perf_event_context *ctx2) | |
564c2b21 | 3241 | { |
211de6eb PZ |
3242 | lockdep_assert_held(&ctx1->lock); |
3243 | lockdep_assert_held(&ctx2->lock); | |
3244 | ||
5a3126d4 PZ |
3245 | /* Pinning disables the swap optimization */ |
3246 | if (ctx1->pin_count || ctx2->pin_count) | |
3247 | return 0; | |
3248 | ||
3249 | /* If ctx1 is the parent of ctx2 */ | |
3250 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3251 | return 1; | |
3252 | ||
3253 | /* If ctx2 is the parent of ctx1 */ | |
3254 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3255 | return 1; | |
3256 | ||
3257 | /* | |
3258 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3259 | * hierarchy, see perf_event_init_context(). | |
3260 | */ | |
3261 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3262 | ctx1->parent_gen == ctx2->parent_gen) | |
3263 | return 1; | |
3264 | ||
3265 | /* Unmatched */ | |
3266 | return 0; | |
564c2b21 PM |
3267 | } |
3268 | ||
cdd6c482 IM |
3269 | static void __perf_event_sync_stat(struct perf_event *event, |
3270 | struct perf_event *next_event) | |
bfbd3381 PZ |
3271 | { |
3272 | u64 value; | |
3273 | ||
cdd6c482 | 3274 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3275 | return; |
3276 | ||
3277 | /* | |
cdd6c482 | 3278 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3279 | * because we're in the middle of a context switch and have IRQs |
3280 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3281 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3282 | * don't need to use it. |
3283 | */ | |
0d3d73aa | 3284 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3285 | event->pmu->read(event); |
bfbd3381 | 3286 | |
0d3d73aa | 3287 | perf_event_update_time(event); |
bfbd3381 PZ |
3288 | |
3289 | /* | |
cdd6c482 | 3290 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3291 | * values when we flip the contexts. |
3292 | */ | |
e7850595 PZ |
3293 | value = local64_read(&next_event->count); |
3294 | value = local64_xchg(&event->count, value); | |
3295 | local64_set(&next_event->count, value); | |
bfbd3381 | 3296 | |
cdd6c482 IM |
3297 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3298 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3299 | |
bfbd3381 | 3300 | /* |
19d2e755 | 3301 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3302 | */ |
cdd6c482 IM |
3303 | perf_event_update_userpage(event); |
3304 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3305 | } |
3306 | ||
cdd6c482 IM |
3307 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3308 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3309 | { |
cdd6c482 | 3310 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3311 | |
3312 | if (!ctx->nr_stat) | |
3313 | return; | |
3314 | ||
02ffdbc8 PZ |
3315 | update_context_time(ctx); |
3316 | ||
cdd6c482 IM |
3317 | event = list_first_entry(&ctx->event_list, |
3318 | struct perf_event, event_entry); | |
bfbd3381 | 3319 | |
cdd6c482 IM |
3320 | next_event = list_first_entry(&next_ctx->event_list, |
3321 | struct perf_event, event_entry); | |
bfbd3381 | 3322 | |
cdd6c482 IM |
3323 | while (&event->event_entry != &ctx->event_list && |
3324 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3325 | |
cdd6c482 | 3326 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3327 | |
cdd6c482 IM |
3328 | event = list_next_entry(event, event_entry); |
3329 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3330 | } |
3331 | } | |
3332 | ||
fe4b04fa PZ |
3333 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3334 | struct task_struct *next) | |
0793a61d | 3335 | { |
8dc85d54 | 3336 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3337 | struct perf_event_context *next_ctx; |
5a3126d4 | 3338 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3339 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3340 | int do_switch = 1; |
0793a61d | 3341 | |
108b02cf PZ |
3342 | if (likely(!ctx)) |
3343 | return; | |
10989fb2 | 3344 | |
108b02cf PZ |
3345 | cpuctx = __get_cpu_context(ctx); |
3346 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3347 | return; |
3348 | ||
c93f7669 | 3349 | rcu_read_lock(); |
8dc85d54 | 3350 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3351 | if (!next_ctx) |
3352 | goto unlock; | |
3353 | ||
3354 | parent = rcu_dereference(ctx->parent_ctx); | |
3355 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3356 | ||
3357 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3358 | if (!parent && !next_parent) |
5a3126d4 PZ |
3359 | goto unlock; |
3360 | ||
3361 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3362 | /* |
3363 | * Looks like the two contexts are clones, so we might be | |
3364 | * able to optimize the context switch. We lock both | |
3365 | * contexts and check that they are clones under the | |
3366 | * lock (including re-checking that neither has been | |
3367 | * uncloned in the meantime). It doesn't matter which | |
3368 | * order we take the locks because no other cpu could | |
3369 | * be trying to lock both of these tasks. | |
3370 | */ | |
e625cce1 TG |
3371 | raw_spin_lock(&ctx->lock); |
3372 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3373 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 AB |
3374 | struct pmu *pmu = ctx->pmu; |
3375 | ||
63b6da39 PZ |
3376 | WRITE_ONCE(ctx->task, next); |
3377 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3378 | |
c2b98a86 AB |
3379 | /* |
3380 | * PMU specific parts of task perf context can require | |
3381 | * additional synchronization. As an example of such | |
3382 | * synchronization see implementation details of Intel | |
3383 | * LBR call stack data profiling; | |
3384 | */ | |
3385 | if (pmu->swap_task_ctx) | |
3386 | pmu->swap_task_ctx(ctx, next_ctx); | |
3387 | else | |
3388 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3389 | |
63b6da39 PZ |
3390 | /* |
3391 | * RCU_INIT_POINTER here is safe because we've not | |
3392 | * modified the ctx and the above modification of | |
3393 | * ctx->task and ctx->task_ctx_data are immaterial | |
3394 | * since those values are always verified under | |
3395 | * ctx->lock which we're now holding. | |
3396 | */ | |
3397 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3398 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3399 | ||
c93f7669 | 3400 | do_switch = 0; |
bfbd3381 | 3401 | |
cdd6c482 | 3402 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3403 | } |
e625cce1 TG |
3404 | raw_spin_unlock(&next_ctx->lock); |
3405 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3406 | } |
5a3126d4 | 3407 | unlock: |
c93f7669 | 3408 | rcu_read_unlock(); |
564c2b21 | 3409 | |
c93f7669 | 3410 | if (do_switch) { |
facc4307 | 3411 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3412 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3413 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3414 | } |
0793a61d TG |
3415 | } |
3416 | ||
e48c1788 PZ |
3417 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3418 | ||
ba532500 YZ |
3419 | void perf_sched_cb_dec(struct pmu *pmu) |
3420 | { | |
e48c1788 PZ |
3421 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3422 | ||
ba532500 | 3423 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3424 | |
3425 | if (!--cpuctx->sched_cb_usage) | |
3426 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3427 | } |
3428 | ||
e48c1788 | 3429 | |
ba532500 YZ |
3430 | void perf_sched_cb_inc(struct pmu *pmu) |
3431 | { | |
e48c1788 PZ |
3432 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3433 | ||
3434 | if (!cpuctx->sched_cb_usage++) | |
3435 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3436 | ||
ba532500 YZ |
3437 | this_cpu_inc(perf_sched_cb_usages); |
3438 | } | |
3439 | ||
3440 | /* | |
3441 | * This function provides the context switch callback to the lower code | |
3442 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3443 | * |
3444 | * This callback is relevant even to per-cpu events; for example multi event | |
3445 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3446 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3447 | */ |
3448 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3449 | struct task_struct *next, | |
3450 | bool sched_in) | |
3451 | { | |
3452 | struct perf_cpu_context *cpuctx; | |
3453 | struct pmu *pmu; | |
ba532500 YZ |
3454 | |
3455 | if (prev == next) | |
3456 | return; | |
3457 | ||
e48c1788 | 3458 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3459 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3460 | |
e48c1788 PZ |
3461 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3462 | continue; | |
ba532500 | 3463 | |
e48c1788 PZ |
3464 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3465 | perf_pmu_disable(pmu); | |
ba532500 | 3466 | |
e48c1788 | 3467 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3468 | |
e48c1788 PZ |
3469 | perf_pmu_enable(pmu); |
3470 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3471 | } |
ba532500 YZ |
3472 | } |
3473 | ||
45ac1403 AH |
3474 | static void perf_event_switch(struct task_struct *task, |
3475 | struct task_struct *next_prev, bool sched_in); | |
3476 | ||
8dc85d54 PZ |
3477 | #define for_each_task_context_nr(ctxn) \ |
3478 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3479 | ||
3480 | /* | |
3481 | * Called from scheduler to remove the events of the current task, | |
3482 | * with interrupts disabled. | |
3483 | * | |
3484 | * We stop each event and update the event value in event->count. | |
3485 | * | |
3486 | * This does not protect us against NMI, but disable() | |
3487 | * sets the disabled bit in the control field of event _before_ | |
3488 | * accessing the event control register. If a NMI hits, then it will | |
3489 | * not restart the event. | |
3490 | */ | |
ab0cce56 JO |
3491 | void __perf_event_task_sched_out(struct task_struct *task, |
3492 | struct task_struct *next) | |
8dc85d54 PZ |
3493 | { |
3494 | int ctxn; | |
3495 | ||
ba532500 YZ |
3496 | if (__this_cpu_read(perf_sched_cb_usages)) |
3497 | perf_pmu_sched_task(task, next, false); | |
3498 | ||
45ac1403 AH |
3499 | if (atomic_read(&nr_switch_events)) |
3500 | perf_event_switch(task, next, false); | |
3501 | ||
8dc85d54 PZ |
3502 | for_each_task_context_nr(ctxn) |
3503 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3504 | |
3505 | /* | |
3506 | * if cgroup events exist on this CPU, then we need | |
3507 | * to check if we have to switch out PMU state. | |
3508 | * cgroup event are system-wide mode only | |
3509 | */ | |
4a32fea9 | 3510 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3511 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3512 | } |
3513 | ||
5b0311e1 FW |
3514 | /* |
3515 | * Called with IRQs disabled | |
3516 | */ | |
3517 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3518 | enum event_type_t event_type) | |
3519 | { | |
3520 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3521 | } |
3522 | ||
6eef8a71 | 3523 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3524 | { |
24fb6b8e IR |
3525 | const struct perf_event *le = *(const struct perf_event **)l; |
3526 | const struct perf_event *re = *(const struct perf_event **)r; | |
6eef8a71 IR |
3527 | |
3528 | return le->group_index < re->group_index; | |
3529 | } | |
3530 | ||
3531 | static void swap_ptr(void *l, void *r) | |
3532 | { | |
3533 | void **lp = l, **rp = r; | |
3534 | ||
3535 | swap(*lp, *rp); | |
3536 | } | |
3537 | ||
3538 | static const struct min_heap_callbacks perf_min_heap = { | |
3539 | .elem_size = sizeof(struct perf_event *), | |
3540 | .less = perf_less_group_idx, | |
3541 | .swp = swap_ptr, | |
3542 | }; | |
3543 | ||
3544 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3545 | { | |
3546 | struct perf_event **itrs = heap->data; | |
3547 | ||
3548 | if (event) { | |
3549 | itrs[heap->nr] = event; | |
3550 | heap->nr++; | |
3551 | } | |
3552 | } | |
3553 | ||
836196be IR |
3554 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3555 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3556 | int (*func)(struct perf_event *, void *), |
3557 | void *data) | |
3558 | { | |
95ed6c70 IR |
3559 | #ifdef CONFIG_CGROUP_PERF |
3560 | struct cgroup_subsys_state *css = NULL; | |
3561 | #endif | |
6eef8a71 IR |
3562 | /* Space for per CPU and/or any CPU event iterators. */ |
3563 | struct perf_event *itrs[2]; | |
836196be IR |
3564 | struct min_heap event_heap; |
3565 | struct perf_event **evt; | |
1cac7b1a | 3566 | int ret; |
8e1a2031 | 3567 | |
836196be IR |
3568 | if (cpuctx) { |
3569 | event_heap = (struct min_heap){ | |
3570 | .data = cpuctx->heap, | |
3571 | .nr = 0, | |
3572 | .size = cpuctx->heap_size, | |
3573 | }; | |
c2283c93 IR |
3574 | |
3575 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3576 | |
3577 | #ifdef CONFIG_CGROUP_PERF | |
3578 | if (cpuctx->cgrp) | |
3579 | css = &cpuctx->cgrp->css; | |
3580 | #endif | |
836196be IR |
3581 | } else { |
3582 | event_heap = (struct min_heap){ | |
3583 | .data = itrs, | |
3584 | .nr = 0, | |
3585 | .size = ARRAY_SIZE(itrs), | |
3586 | }; | |
3587 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3588 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3589 | } |
3590 | evt = event_heap.data; | |
3591 | ||
95ed6c70 IR |
3592 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3593 | ||
3594 | #ifdef CONFIG_CGROUP_PERF | |
3595 | for (; css; css = css->parent) | |
3596 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3597 | #endif | |
1cac7b1a | 3598 | |
6eef8a71 | 3599 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3600 | |
6eef8a71 | 3601 | while (event_heap.nr) { |
1cac7b1a PZ |
3602 | ret = func(*evt, data); |
3603 | if (ret) | |
3604 | return ret; | |
3605 | ||
3606 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3607 | if (*evt) |
3608 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3609 | else | |
3610 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3611 | } |
0793a61d | 3612 | |
1cac7b1a PZ |
3613 | return 0; |
3614 | } | |
3615 | ||
ab6f824c | 3616 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3617 | { |
2c2366c7 PZ |
3618 | struct perf_event_context *ctx = event->ctx; |
3619 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3620 | int *can_add_hw = data; | |
ab6f824c | 3621 | |
1cac7b1a PZ |
3622 | if (event->state <= PERF_EVENT_STATE_OFF) |
3623 | return 0; | |
3624 | ||
3625 | if (!event_filter_match(event)) | |
3626 | return 0; | |
3627 | ||
2c2366c7 PZ |
3628 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3629 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3630 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3631 | } |
1cac7b1a | 3632 | |
ab6f824c | 3633 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
33238c50 PZ |
3634 | if (event->attr.pinned) { |
3635 | perf_cgroup_event_disable(event, ctx); | |
ab6f824c | 3636 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); |
33238c50 | 3637 | } |
1cac7b1a | 3638 | |
2c2366c7 PZ |
3639 | *can_add_hw = 0; |
3640 | ctx->rotate_necessary = 1; | |
3b6f9e5c | 3641 | } |
1cac7b1a PZ |
3642 | |
3643 | return 0; | |
5b0311e1 FW |
3644 | } |
3645 | ||
3646 | static void | |
1cac7b1a PZ |
3647 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3648 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3649 | { |
2c2366c7 | 3650 | int can_add_hw = 1; |
3b6f9e5c | 3651 | |
836196be IR |
3652 | if (ctx != &cpuctx->ctx) |
3653 | cpuctx = NULL; | |
3654 | ||
3655 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3656 | smp_processor_id(), |
2c2366c7 | 3657 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3658 | } |
8e1a2031 | 3659 | |
1cac7b1a PZ |
3660 | static void |
3661 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3662 | struct perf_cpu_context *cpuctx) | |
3663 | { | |
2c2366c7 | 3664 | int can_add_hw = 1; |
0793a61d | 3665 | |
836196be IR |
3666 | if (ctx != &cpuctx->ctx) |
3667 | cpuctx = NULL; | |
3668 | ||
3669 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3670 | smp_processor_id(), |
2c2366c7 | 3671 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3672 | } |
3673 | ||
3674 | static void | |
3675 | ctx_sched_in(struct perf_event_context *ctx, | |
3676 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3677 | enum event_type_t event_type, |
3678 | struct task_struct *task) | |
5b0311e1 | 3679 | { |
db24d33e | 3680 | int is_active = ctx->is_active; |
c994d613 PZ |
3681 | u64 now; |
3682 | ||
3683 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3684 | |
5b0311e1 | 3685 | if (likely(!ctx->nr_events)) |
facc4307 | 3686 | return; |
5b0311e1 | 3687 | |
3cbaa590 | 3688 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3689 | if (ctx->task) { |
3690 | if (!is_active) | |
3691 | cpuctx->task_ctx = ctx; | |
3692 | else | |
3693 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3694 | } | |
3695 | ||
3cbaa590 PZ |
3696 | is_active ^= ctx->is_active; /* changed bits */ |
3697 | ||
3698 | if (is_active & EVENT_TIME) { | |
3699 | /* start ctx time */ | |
3700 | now = perf_clock(); | |
3701 | ctx->timestamp = now; | |
3702 | perf_cgroup_set_timestamp(task, ctx); | |
3703 | } | |
3704 | ||
5b0311e1 FW |
3705 | /* |
3706 | * First go through the list and put on any pinned groups | |
3707 | * in order to give them the best chance of going on. | |
3708 | */ | |
3cbaa590 | 3709 | if (is_active & EVENT_PINNED) |
6e37738a | 3710 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3711 | |
3712 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3713 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3714 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3715 | } |
3716 | ||
329c0e01 | 3717 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3718 | enum event_type_t event_type, |
3719 | struct task_struct *task) | |
329c0e01 FW |
3720 | { |
3721 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3722 | ||
e5d1367f | 3723 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3724 | } |
3725 | ||
e5d1367f SE |
3726 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3727 | struct task_struct *task) | |
235c7fc7 | 3728 | { |
108b02cf | 3729 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3730 | |
108b02cf | 3731 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3732 | if (cpuctx->task_ctx == ctx) |
3733 | return; | |
3734 | ||
facc4307 | 3735 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3736 | /* |
3737 | * We must check ctx->nr_events while holding ctx->lock, such | |
3738 | * that we serialize against perf_install_in_context(). | |
3739 | */ | |
3740 | if (!ctx->nr_events) | |
3741 | goto unlock; | |
3742 | ||
1b9a644f | 3743 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3744 | /* |
3745 | * We want to keep the following priority order: | |
3746 | * cpu pinned (that don't need to move), task pinned, | |
3747 | * cpu flexible, task flexible. | |
fe45bafb AS |
3748 | * |
3749 | * However, if task's ctx is not carrying any pinned | |
3750 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3751 | */ |
8e1a2031 | 3752 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3753 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3754 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3755 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3756 | |
3757 | unlock: | |
facc4307 | 3758 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3759 | } |
3760 | ||
8dc85d54 PZ |
3761 | /* |
3762 | * Called from scheduler to add the events of the current task | |
3763 | * with interrupts disabled. | |
3764 | * | |
3765 | * We restore the event value and then enable it. | |
3766 | * | |
3767 | * This does not protect us against NMI, but enable() | |
3768 | * sets the enabled bit in the control field of event _before_ | |
3769 | * accessing the event control register. If a NMI hits, then it will | |
3770 | * keep the event running. | |
3771 | */ | |
ab0cce56 JO |
3772 | void __perf_event_task_sched_in(struct task_struct *prev, |
3773 | struct task_struct *task) | |
8dc85d54 PZ |
3774 | { |
3775 | struct perf_event_context *ctx; | |
3776 | int ctxn; | |
3777 | ||
7e41d177 PZ |
3778 | /* |
3779 | * If cgroup events exist on this CPU, then we need to check if we have | |
3780 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3781 | * | |
3782 | * Since cgroup events are CPU events, we must schedule these in before | |
3783 | * we schedule in the task events. | |
3784 | */ | |
3785 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3786 | perf_cgroup_sched_in(prev, task); | |
3787 | ||
8dc85d54 PZ |
3788 | for_each_task_context_nr(ctxn) { |
3789 | ctx = task->perf_event_ctxp[ctxn]; | |
3790 | if (likely(!ctx)) | |
3791 | continue; | |
3792 | ||
e5d1367f | 3793 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3794 | } |
d010b332 | 3795 | |
45ac1403 AH |
3796 | if (atomic_read(&nr_switch_events)) |
3797 | perf_event_switch(task, prev, true); | |
3798 | ||
ba532500 YZ |
3799 | if (__this_cpu_read(perf_sched_cb_usages)) |
3800 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3801 | } |
3802 | ||
abd50713 PZ |
3803 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3804 | { | |
3805 | u64 frequency = event->attr.sample_freq; | |
3806 | u64 sec = NSEC_PER_SEC; | |
3807 | u64 divisor, dividend; | |
3808 | ||
3809 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3810 | ||
3811 | count_fls = fls64(count); | |
3812 | nsec_fls = fls64(nsec); | |
3813 | frequency_fls = fls64(frequency); | |
3814 | sec_fls = 30; | |
3815 | ||
3816 | /* | |
3817 | * We got @count in @nsec, with a target of sample_freq HZ | |
3818 | * the target period becomes: | |
3819 | * | |
3820 | * @count * 10^9 | |
3821 | * period = ------------------- | |
3822 | * @nsec * sample_freq | |
3823 | * | |
3824 | */ | |
3825 | ||
3826 | /* | |
3827 | * Reduce accuracy by one bit such that @a and @b converge | |
3828 | * to a similar magnitude. | |
3829 | */ | |
fe4b04fa | 3830 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3831 | do { \ |
3832 | if (a##_fls > b##_fls) { \ | |
3833 | a >>= 1; \ | |
3834 | a##_fls--; \ | |
3835 | } else { \ | |
3836 | b >>= 1; \ | |
3837 | b##_fls--; \ | |
3838 | } \ | |
3839 | } while (0) | |
3840 | ||
3841 | /* | |
3842 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3843 | * the other, so that finally we can do a u64/u64 division. | |
3844 | */ | |
3845 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3846 | REDUCE_FLS(nsec, frequency); | |
3847 | REDUCE_FLS(sec, count); | |
3848 | } | |
3849 | ||
3850 | if (count_fls + sec_fls > 64) { | |
3851 | divisor = nsec * frequency; | |
3852 | ||
3853 | while (count_fls + sec_fls > 64) { | |
3854 | REDUCE_FLS(count, sec); | |
3855 | divisor >>= 1; | |
3856 | } | |
3857 | ||
3858 | dividend = count * sec; | |
3859 | } else { | |
3860 | dividend = count * sec; | |
3861 | ||
3862 | while (nsec_fls + frequency_fls > 64) { | |
3863 | REDUCE_FLS(nsec, frequency); | |
3864 | dividend >>= 1; | |
3865 | } | |
3866 | ||
3867 | divisor = nsec * frequency; | |
3868 | } | |
3869 | ||
f6ab91ad PZ |
3870 | if (!divisor) |
3871 | return dividend; | |
3872 | ||
abd50713 PZ |
3873 | return div64_u64(dividend, divisor); |
3874 | } | |
3875 | ||
e050e3f0 SE |
3876 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3877 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3878 | ||
f39d47ff | 3879 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3880 | { |
cdd6c482 | 3881 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3882 | s64 period, sample_period; |
bd2b5b12 PZ |
3883 | s64 delta; |
3884 | ||
abd50713 | 3885 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3886 | |
3887 | delta = (s64)(period - hwc->sample_period); | |
3888 | delta = (delta + 7) / 8; /* low pass filter */ | |
3889 | ||
3890 | sample_period = hwc->sample_period + delta; | |
3891 | ||
3892 | if (!sample_period) | |
3893 | sample_period = 1; | |
3894 | ||
bd2b5b12 | 3895 | hwc->sample_period = sample_period; |
abd50713 | 3896 | |
e7850595 | 3897 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3898 | if (disable) |
3899 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3900 | ||
e7850595 | 3901 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3902 | |
3903 | if (disable) | |
3904 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3905 | } |
bd2b5b12 PZ |
3906 | } |
3907 | ||
e050e3f0 SE |
3908 | /* |
3909 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3910 | * events. At the same time, make sure, having freq events does not change | |
3911 | * the rate of unthrottling as that would introduce bias. | |
3912 | */ | |
3913 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3914 | int needs_unthr) | |
60db5e09 | 3915 | { |
cdd6c482 IM |
3916 | struct perf_event *event; |
3917 | struct hw_perf_event *hwc; | |
e050e3f0 | 3918 | u64 now, period = TICK_NSEC; |
abd50713 | 3919 | s64 delta; |
60db5e09 | 3920 | |
e050e3f0 SE |
3921 | /* |
3922 | * only need to iterate over all events iff: | |
3923 | * - context have events in frequency mode (needs freq adjust) | |
3924 | * - there are events to unthrottle on this cpu | |
3925 | */ | |
3926 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3927 | return; |
3928 | ||
e050e3f0 | 3929 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3930 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3931 | |
03541f8b | 3932 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3933 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3934 | continue; |
3935 | ||
5632ab12 | 3936 | if (!event_filter_match(event)) |
5d27c23d PZ |
3937 | continue; |
3938 | ||
44377277 AS |
3939 | perf_pmu_disable(event->pmu); |
3940 | ||
cdd6c482 | 3941 | hwc = &event->hw; |
6a24ed6c | 3942 | |
ae23bff1 | 3943 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3944 | hwc->interrupts = 0; |
cdd6c482 | 3945 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3946 | event->pmu->start(event, 0); |
a78ac325 PZ |
3947 | } |
3948 | ||
cdd6c482 | 3949 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3950 | goto next; |
60db5e09 | 3951 | |
e050e3f0 SE |
3952 | /* |
3953 | * stop the event and update event->count | |
3954 | */ | |
3955 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3956 | ||
e7850595 | 3957 | now = local64_read(&event->count); |
abd50713 PZ |
3958 | delta = now - hwc->freq_count_stamp; |
3959 | hwc->freq_count_stamp = now; | |
60db5e09 | 3960 | |
e050e3f0 SE |
3961 | /* |
3962 | * restart the event | |
3963 | * reload only if value has changed | |
f39d47ff SE |
3964 | * we have stopped the event so tell that |
3965 | * to perf_adjust_period() to avoid stopping it | |
3966 | * twice. | |
e050e3f0 | 3967 | */ |
abd50713 | 3968 | if (delta > 0) |
f39d47ff | 3969 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3970 | |
3971 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3972 | next: |
3973 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3974 | } |
e050e3f0 | 3975 | |
f39d47ff | 3976 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3977 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3978 | } |
3979 | ||
235c7fc7 | 3980 | /* |
8703a7cf | 3981 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3982 | */ |
8703a7cf | 3983 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3984 | { |
dddd3379 TG |
3985 | /* |
3986 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3987 | * disabled by the inheritance code. | |
3988 | */ | |
8703a7cf PZ |
3989 | if (ctx->rotate_disable) |
3990 | return; | |
8e1a2031 | 3991 | |
8703a7cf PZ |
3992 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3993 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3994 | } |
3995 | ||
7fa343b7 | 3996 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 3997 | static inline struct perf_event * |
7fa343b7 | 3998 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 3999 | { |
7fa343b7 SL |
4000 | struct perf_event *event; |
4001 | ||
4002 | /* pick the first active flexible event */ | |
4003 | event = list_first_entry_or_null(&ctx->flexible_active, | |
4004 | struct perf_event, active_list); | |
4005 | ||
4006 | /* if no active flexible event, pick the first event */ | |
4007 | if (!event) { | |
4008 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
4009 | typeof(*event), group_node); | |
4010 | } | |
4011 | ||
90c91dfb PZ |
4012 | /* |
4013 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
4014 | * finds there are unschedulable events, it will set it again. | |
4015 | */ | |
4016 | ctx->rotate_necessary = 0; | |
4017 | ||
7fa343b7 | 4018 | return event; |
8d5bce0c PZ |
4019 | } |
4020 | ||
4021 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4022 | { | |
4023 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4024 | struct perf_event_context *task_ctx = NULL; |
4025 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4026 | |
4027 | /* | |
4028 | * Since we run this from IRQ context, nobody can install new | |
4029 | * events, thus the event count values are stable. | |
4030 | */ | |
7fc23a53 | 4031 | |
fd7d5517 IR |
4032 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4033 | task_ctx = cpuctx->task_ctx; | |
4034 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4035 | |
8d5bce0c PZ |
4036 | if (!(cpu_rotate || task_rotate)) |
4037 | return false; | |
0f5a2601 | 4038 | |
facc4307 | 4039 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4040 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4041 | |
8d5bce0c | 4042 | if (task_rotate) |
7fa343b7 | 4043 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4044 | if (cpu_rotate) |
7fa343b7 | 4045 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4046 | |
8d5bce0c PZ |
4047 | /* |
4048 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4049 | * and then, if needed CPU flexible. | |
4050 | */ | |
fd7d5517 IR |
4051 | if (task_event || (task_ctx && cpu_event)) |
4052 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4053 | if (cpu_event) |
4054 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4055 | |
8d5bce0c | 4056 | if (task_event) |
fd7d5517 | 4057 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4058 | if (cpu_event) |
4059 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4060 | |
fd7d5517 | 4061 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4062 | |
0f5a2601 PZ |
4063 | perf_pmu_enable(cpuctx->ctx.pmu); |
4064 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4065 | |
8d5bce0c | 4066 | return true; |
e9d2b064 PZ |
4067 | } |
4068 | ||
4069 | void perf_event_task_tick(void) | |
4070 | { | |
2fde4f94 MR |
4071 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4072 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4073 | int throttled; |
b5ab4cd5 | 4074 | |
16444645 | 4075 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4076 | |
e050e3f0 SE |
4077 | __this_cpu_inc(perf_throttled_seq); |
4078 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4079 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4080 | |
2fde4f94 | 4081 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4082 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4083 | } |
4084 | ||
889ff015 FW |
4085 | static int event_enable_on_exec(struct perf_event *event, |
4086 | struct perf_event_context *ctx) | |
4087 | { | |
4088 | if (!event->attr.enable_on_exec) | |
4089 | return 0; | |
4090 | ||
4091 | event->attr.enable_on_exec = 0; | |
4092 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4093 | return 0; | |
4094 | ||
0d3d73aa | 4095 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4096 | |
4097 | return 1; | |
4098 | } | |
4099 | ||
57e7986e | 4100 | /* |
cdd6c482 | 4101 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4102 | * This expects task == current. |
4103 | */ | |
c1274499 | 4104 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4105 | { |
c1274499 | 4106 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4107 | enum event_type_t event_type = 0; |
3e349507 | 4108 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4109 | struct perf_event *event; |
57e7986e PM |
4110 | unsigned long flags; |
4111 | int enabled = 0; | |
4112 | ||
4113 | local_irq_save(flags); | |
c1274499 | 4114 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4115 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4116 | goto out; |
4117 | ||
3e349507 PZ |
4118 | cpuctx = __get_cpu_context(ctx); |
4119 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4120 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4121 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4122 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4123 | event_type |= get_event_type(event); |
4124 | } | |
57e7986e PM |
4125 | |
4126 | /* | |
3e349507 | 4127 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4128 | */ |
3e349507 | 4129 | if (enabled) { |
211de6eb | 4130 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4131 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4132 | } else { |
4133 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4134 | } |
4135 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4136 | |
9ed6060d | 4137 | out: |
57e7986e | 4138 | local_irq_restore(flags); |
211de6eb PZ |
4139 | |
4140 | if (clone_ctx) | |
4141 | put_ctx(clone_ctx); | |
57e7986e PM |
4142 | } |
4143 | ||
0492d4c5 PZ |
4144 | struct perf_read_data { |
4145 | struct perf_event *event; | |
4146 | bool group; | |
7d88962e | 4147 | int ret; |
0492d4c5 PZ |
4148 | }; |
4149 | ||
451d24d1 | 4150 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4151 | { |
d6a2f903 DCC |
4152 | u16 local_pkg, event_pkg; |
4153 | ||
4154 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4155 | int local_cpu = smp_processor_id(); |
4156 | ||
4157 | event_pkg = topology_physical_package_id(event_cpu); | |
4158 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4159 | |
4160 | if (event_pkg == local_pkg) | |
4161 | return local_cpu; | |
4162 | } | |
4163 | ||
4164 | return event_cpu; | |
4165 | } | |
4166 | ||
0793a61d | 4167 | /* |
cdd6c482 | 4168 | * Cross CPU call to read the hardware event |
0793a61d | 4169 | */ |
cdd6c482 | 4170 | static void __perf_event_read(void *info) |
0793a61d | 4171 | { |
0492d4c5 PZ |
4172 | struct perf_read_data *data = info; |
4173 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4174 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4175 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4176 | struct pmu *pmu = event->pmu; |
621a01ea | 4177 | |
e1ac3614 PM |
4178 | /* |
4179 | * If this is a task context, we need to check whether it is | |
4180 | * the current task context of this cpu. If not it has been | |
4181 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4182 | * event->count would have been updated to a recent sample |
4183 | * when the event was scheduled out. | |
e1ac3614 PM |
4184 | */ |
4185 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4186 | return; | |
4187 | ||
e625cce1 | 4188 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4189 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4190 | update_context_time(ctx); |
e5d1367f SE |
4191 | update_cgrp_time_from_event(event); |
4192 | } | |
0492d4c5 | 4193 | |
0d3d73aa PZ |
4194 | perf_event_update_time(event); |
4195 | if (data->group) | |
4196 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4197 | |
4a00c16e SB |
4198 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4199 | goto unlock; | |
0492d4c5 | 4200 | |
4a00c16e SB |
4201 | if (!data->group) { |
4202 | pmu->read(event); | |
4203 | data->ret = 0; | |
0492d4c5 | 4204 | goto unlock; |
4a00c16e SB |
4205 | } |
4206 | ||
4207 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4208 | ||
4209 | pmu->read(event); | |
0492d4c5 | 4210 | |
edb39592 | 4211 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4212 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4213 | /* | |
4214 | * Use sibling's PMU rather than @event's since | |
4215 | * sibling could be on different (eg: software) PMU. | |
4216 | */ | |
0492d4c5 | 4217 | sub->pmu->read(sub); |
4a00c16e | 4218 | } |
0492d4c5 | 4219 | } |
4a00c16e SB |
4220 | |
4221 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4222 | |
4223 | unlock: | |
e625cce1 | 4224 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4225 | } |
4226 | ||
b5e58793 PZ |
4227 | static inline u64 perf_event_count(struct perf_event *event) |
4228 | { | |
c39a0e2c | 4229 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4230 | } |
4231 | ||
ffe8690c KX |
4232 | /* |
4233 | * NMI-safe method to read a local event, that is an event that | |
4234 | * is: | |
4235 | * - either for the current task, or for this CPU | |
4236 | * - does not have inherit set, for inherited task events | |
4237 | * will not be local and we cannot read them atomically | |
4238 | * - must not have a pmu::count method | |
4239 | */ | |
7d9285e8 YS |
4240 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4241 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4242 | { |
4243 | unsigned long flags; | |
f91840a3 | 4244 | int ret = 0; |
ffe8690c KX |
4245 | |
4246 | /* | |
4247 | * Disabling interrupts avoids all counter scheduling (context | |
4248 | * switches, timer based rotation and IPIs). | |
4249 | */ | |
4250 | local_irq_save(flags); | |
4251 | ||
ffe8690c KX |
4252 | /* |
4253 | * It must not be an event with inherit set, we cannot read | |
4254 | * all child counters from atomic context. | |
4255 | */ | |
f91840a3 AS |
4256 | if (event->attr.inherit) { |
4257 | ret = -EOPNOTSUPP; | |
4258 | goto out; | |
4259 | } | |
ffe8690c | 4260 | |
f91840a3 AS |
4261 | /* If this is a per-task event, it must be for current */ |
4262 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4263 | event->hw.target != current) { | |
4264 | ret = -EINVAL; | |
4265 | goto out; | |
4266 | } | |
4267 | ||
4268 | /* If this is a per-CPU event, it must be for this CPU */ | |
4269 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4270 | event->cpu != smp_processor_id()) { | |
4271 | ret = -EINVAL; | |
4272 | goto out; | |
4273 | } | |
ffe8690c | 4274 | |
befb1b3c RC |
4275 | /* If this is a pinned event it must be running on this CPU */ |
4276 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4277 | ret = -EBUSY; | |
4278 | goto out; | |
4279 | } | |
4280 | ||
ffe8690c KX |
4281 | /* |
4282 | * If the event is currently on this CPU, its either a per-task event, | |
4283 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4284 | * oncpu == -1). | |
4285 | */ | |
4286 | if (event->oncpu == smp_processor_id()) | |
4287 | event->pmu->read(event); | |
4288 | ||
f91840a3 | 4289 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4290 | if (enabled || running) { |
4291 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4292 | u64 __enabled, __running; | |
4293 | ||
4294 | __perf_update_times(event, now, &__enabled, &__running); | |
4295 | if (enabled) | |
4296 | *enabled = __enabled; | |
4297 | if (running) | |
4298 | *running = __running; | |
4299 | } | |
f91840a3 | 4300 | out: |
ffe8690c KX |
4301 | local_irq_restore(flags); |
4302 | ||
f91840a3 | 4303 | return ret; |
ffe8690c KX |
4304 | } |
4305 | ||
7d88962e | 4306 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4307 | { |
0c1cbc18 | 4308 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4309 | int event_cpu, ret = 0; |
7d88962e | 4310 | |
0793a61d | 4311 | /* |
cdd6c482 IM |
4312 | * If event is enabled and currently active on a CPU, update the |
4313 | * value in the event structure: | |
0793a61d | 4314 | */ |
0c1cbc18 PZ |
4315 | again: |
4316 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4317 | struct perf_read_data data; | |
4318 | ||
4319 | /* | |
4320 | * Orders the ->state and ->oncpu loads such that if we see | |
4321 | * ACTIVE we must also see the right ->oncpu. | |
4322 | * | |
4323 | * Matches the smp_wmb() from event_sched_in(). | |
4324 | */ | |
4325 | smp_rmb(); | |
d6a2f903 | 4326 | |
451d24d1 PZ |
4327 | event_cpu = READ_ONCE(event->oncpu); |
4328 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4329 | return 0; | |
4330 | ||
0c1cbc18 PZ |
4331 | data = (struct perf_read_data){ |
4332 | .event = event, | |
4333 | .group = group, | |
4334 | .ret = 0, | |
4335 | }; | |
4336 | ||
451d24d1 PZ |
4337 | preempt_disable(); |
4338 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4339 | |
58763148 PZ |
4340 | /* |
4341 | * Purposely ignore the smp_call_function_single() return | |
4342 | * value. | |
4343 | * | |
451d24d1 | 4344 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4345 | * scheduled out and that will have updated the event count. |
4346 | * | |
4347 | * Therefore, either way, we'll have an up-to-date event count | |
4348 | * after this. | |
4349 | */ | |
451d24d1 PZ |
4350 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4351 | preempt_enable(); | |
58763148 | 4352 | ret = data.ret; |
0c1cbc18 PZ |
4353 | |
4354 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4355 | struct perf_event_context *ctx = event->ctx; |
4356 | unsigned long flags; | |
4357 | ||
e625cce1 | 4358 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4359 | state = event->state; |
4360 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4361 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4362 | goto again; | |
4363 | } | |
4364 | ||
c530ccd9 | 4365 | /* |
0c1cbc18 PZ |
4366 | * May read while context is not active (e.g., thread is |
4367 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4368 | */ |
0c1cbc18 | 4369 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4370 | update_context_time(ctx); |
e5d1367f SE |
4371 | update_cgrp_time_from_event(event); |
4372 | } | |
0c1cbc18 | 4373 | |
0d3d73aa | 4374 | perf_event_update_time(event); |
0492d4c5 | 4375 | if (group) |
0d3d73aa | 4376 | perf_event_update_sibling_time(event); |
e625cce1 | 4377 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4378 | } |
7d88962e SB |
4379 | |
4380 | return ret; | |
0793a61d TG |
4381 | } |
4382 | ||
a63eaf34 | 4383 | /* |
cdd6c482 | 4384 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4385 | */ |
eb184479 | 4386 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4387 | { |
e625cce1 | 4388 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4389 | mutex_init(&ctx->mutex); |
2fde4f94 | 4390 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4391 | perf_event_groups_init(&ctx->pinned_groups); |
4392 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4393 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4394 | INIT_LIST_HEAD(&ctx->pinned_active); |
4395 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4396 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4397 | } |
4398 | ||
4399 | static struct perf_event_context * | |
4400 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4401 | { | |
4402 | struct perf_event_context *ctx; | |
4403 | ||
4404 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4405 | if (!ctx) | |
4406 | return NULL; | |
4407 | ||
4408 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4409 | if (task) |
4410 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4411 | ctx->pmu = pmu; |
4412 | ||
4413 | return ctx; | |
a63eaf34 PM |
4414 | } |
4415 | ||
2ebd4ffb MH |
4416 | static struct task_struct * |
4417 | find_lively_task_by_vpid(pid_t vpid) | |
4418 | { | |
4419 | struct task_struct *task; | |
0793a61d TG |
4420 | |
4421 | rcu_read_lock(); | |
2ebd4ffb | 4422 | if (!vpid) |
0793a61d TG |
4423 | task = current; |
4424 | else | |
2ebd4ffb | 4425 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4426 | if (task) |
4427 | get_task_struct(task); | |
4428 | rcu_read_unlock(); | |
4429 | ||
4430 | if (!task) | |
4431 | return ERR_PTR(-ESRCH); | |
4432 | ||
2ebd4ffb | 4433 | return task; |
2ebd4ffb MH |
4434 | } |
4435 | ||
fe4b04fa PZ |
4436 | /* |
4437 | * Returns a matching context with refcount and pincount. | |
4438 | */ | |
108b02cf | 4439 | static struct perf_event_context * |
4af57ef2 YZ |
4440 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4441 | struct perf_event *event) | |
0793a61d | 4442 | { |
211de6eb | 4443 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4444 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4445 | void *task_ctx_data = NULL; |
25346b93 | 4446 | unsigned long flags; |
8dc85d54 | 4447 | int ctxn, err; |
4af57ef2 | 4448 | int cpu = event->cpu; |
0793a61d | 4449 | |
22a4ec72 | 4450 | if (!task) { |
cdd6c482 | 4451 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4452 | err = perf_allow_cpu(&event->attr); |
4453 | if (err) | |
4454 | return ERR_PTR(err); | |
0793a61d | 4455 | |
108b02cf | 4456 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4457 | ctx = &cpuctx->ctx; |
c93f7669 | 4458 | get_ctx(ctx); |
fe4b04fa | 4459 | ++ctx->pin_count; |
0793a61d | 4460 | |
0793a61d TG |
4461 | return ctx; |
4462 | } | |
4463 | ||
8dc85d54 PZ |
4464 | err = -EINVAL; |
4465 | ctxn = pmu->task_ctx_nr; | |
4466 | if (ctxn < 0) | |
4467 | goto errout; | |
4468 | ||
4af57ef2 YZ |
4469 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4470 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4471 | if (!task_ctx_data) { | |
4472 | err = -ENOMEM; | |
4473 | goto errout; | |
4474 | } | |
4475 | } | |
4476 | ||
9ed6060d | 4477 | retry: |
8dc85d54 | 4478 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4479 | if (ctx) { |
211de6eb | 4480 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4481 | ++ctx->pin_count; |
4af57ef2 YZ |
4482 | |
4483 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4484 | ctx->task_ctx_data = task_ctx_data; | |
4485 | task_ctx_data = NULL; | |
4486 | } | |
e625cce1 | 4487 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4488 | |
4489 | if (clone_ctx) | |
4490 | put_ctx(clone_ctx); | |
9137fb28 | 4491 | } else { |
eb184479 | 4492 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4493 | err = -ENOMEM; |
4494 | if (!ctx) | |
4495 | goto errout; | |
eb184479 | 4496 | |
4af57ef2 YZ |
4497 | if (task_ctx_data) { |
4498 | ctx->task_ctx_data = task_ctx_data; | |
4499 | task_ctx_data = NULL; | |
4500 | } | |
4501 | ||
dbe08d82 ON |
4502 | err = 0; |
4503 | mutex_lock(&task->perf_event_mutex); | |
4504 | /* | |
4505 | * If it has already passed perf_event_exit_task(). | |
4506 | * we must see PF_EXITING, it takes this mutex too. | |
4507 | */ | |
4508 | if (task->flags & PF_EXITING) | |
4509 | err = -ESRCH; | |
4510 | else if (task->perf_event_ctxp[ctxn]) | |
4511 | err = -EAGAIN; | |
fe4b04fa | 4512 | else { |
9137fb28 | 4513 | get_ctx(ctx); |
fe4b04fa | 4514 | ++ctx->pin_count; |
dbe08d82 | 4515 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4516 | } |
dbe08d82 ON |
4517 | mutex_unlock(&task->perf_event_mutex); |
4518 | ||
4519 | if (unlikely(err)) { | |
9137fb28 | 4520 | put_ctx(ctx); |
dbe08d82 ON |
4521 | |
4522 | if (err == -EAGAIN) | |
4523 | goto retry; | |
4524 | goto errout; | |
a63eaf34 PM |
4525 | } |
4526 | } | |
4527 | ||
4af57ef2 | 4528 | kfree(task_ctx_data); |
0793a61d | 4529 | return ctx; |
c93f7669 | 4530 | |
9ed6060d | 4531 | errout: |
4af57ef2 | 4532 | kfree(task_ctx_data); |
c93f7669 | 4533 | return ERR_PTR(err); |
0793a61d TG |
4534 | } |
4535 | ||
6fb2915d | 4536 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4537 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4538 | |
cdd6c482 | 4539 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4540 | { |
cdd6c482 | 4541 | struct perf_event *event; |
592903cd | 4542 | |
cdd6c482 IM |
4543 | event = container_of(head, struct perf_event, rcu_head); |
4544 | if (event->ns) | |
4545 | put_pid_ns(event->ns); | |
6fb2915d | 4546 | perf_event_free_filter(event); |
cdd6c482 | 4547 | kfree(event); |
592903cd PZ |
4548 | } |
4549 | ||
b69cf536 | 4550 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4551 | struct perf_buffer *rb); |
925d519a | 4552 | |
f2fb6bef KL |
4553 | static void detach_sb_event(struct perf_event *event) |
4554 | { | |
4555 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4556 | ||
4557 | raw_spin_lock(&pel->lock); | |
4558 | list_del_rcu(&event->sb_list); | |
4559 | raw_spin_unlock(&pel->lock); | |
4560 | } | |
4561 | ||
a4f144eb | 4562 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4563 | { |
a4f144eb DCC |
4564 | struct perf_event_attr *attr = &event->attr; |
4565 | ||
f2fb6bef | 4566 | if (event->parent) |
a4f144eb | 4567 | return false; |
f2fb6bef KL |
4568 | |
4569 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4570 | return false; |
f2fb6bef | 4571 | |
a4f144eb DCC |
4572 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4573 | attr->comm || attr->comm_exec || | |
76193a94 | 4574 | attr->task || attr->ksymbol || |
21038f2b SL |
4575 | attr->context_switch || |
4576 | attr->bpf_event) | |
a4f144eb DCC |
4577 | return true; |
4578 | return false; | |
4579 | } | |
4580 | ||
4581 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4582 | { | |
4583 | if (is_sb_event(event)) | |
4584 | detach_sb_event(event); | |
f2fb6bef KL |
4585 | } |
4586 | ||
4beb31f3 | 4587 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4588 | { |
4beb31f3 FW |
4589 | if (event->parent) |
4590 | return; | |
4591 | ||
4beb31f3 FW |
4592 | if (is_cgroup_event(event)) |
4593 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4594 | } | |
925d519a | 4595 | |
555e0c1e FW |
4596 | #ifdef CONFIG_NO_HZ_FULL |
4597 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4598 | #endif | |
4599 | ||
4600 | static void unaccount_freq_event_nohz(void) | |
4601 | { | |
4602 | #ifdef CONFIG_NO_HZ_FULL | |
4603 | spin_lock(&nr_freq_lock); | |
4604 | if (atomic_dec_and_test(&nr_freq_events)) | |
4605 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4606 | spin_unlock(&nr_freq_lock); | |
4607 | #endif | |
4608 | } | |
4609 | ||
4610 | static void unaccount_freq_event(void) | |
4611 | { | |
4612 | if (tick_nohz_full_enabled()) | |
4613 | unaccount_freq_event_nohz(); | |
4614 | else | |
4615 | atomic_dec(&nr_freq_events); | |
4616 | } | |
4617 | ||
4beb31f3 FW |
4618 | static void unaccount_event(struct perf_event *event) |
4619 | { | |
25432ae9 PZ |
4620 | bool dec = false; |
4621 | ||
4beb31f3 FW |
4622 | if (event->parent) |
4623 | return; | |
4624 | ||
4625 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4626 | dec = true; |
4beb31f3 FW |
4627 | if (event->attr.mmap || event->attr.mmap_data) |
4628 | atomic_dec(&nr_mmap_events); | |
4629 | if (event->attr.comm) | |
4630 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4631 | if (event->attr.namespaces) |
4632 | atomic_dec(&nr_namespaces_events); | |
96aaab68 NK |
4633 | if (event->attr.cgroup) |
4634 | atomic_dec(&nr_cgroup_events); | |
4beb31f3 FW |
4635 | if (event->attr.task) |
4636 | atomic_dec(&nr_task_events); | |
948b26b6 | 4637 | if (event->attr.freq) |
555e0c1e | 4638 | unaccount_freq_event(); |
45ac1403 | 4639 | if (event->attr.context_switch) { |
25432ae9 | 4640 | dec = true; |
45ac1403 AH |
4641 | atomic_dec(&nr_switch_events); |
4642 | } | |
4beb31f3 | 4643 | if (is_cgroup_event(event)) |
25432ae9 | 4644 | dec = true; |
4beb31f3 | 4645 | if (has_branch_stack(event)) |
25432ae9 | 4646 | dec = true; |
76193a94 SL |
4647 | if (event->attr.ksymbol) |
4648 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4649 | if (event->attr.bpf_event) |
4650 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4651 | |
9107c89e PZ |
4652 | if (dec) { |
4653 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4654 | schedule_delayed_work(&perf_sched_work, HZ); | |
4655 | } | |
4beb31f3 FW |
4656 | |
4657 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4658 | |
4659 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4660 | } |
925d519a | 4661 | |
9107c89e PZ |
4662 | static void perf_sched_delayed(struct work_struct *work) |
4663 | { | |
4664 | mutex_lock(&perf_sched_mutex); | |
4665 | if (atomic_dec_and_test(&perf_sched_count)) | |
4666 | static_branch_disable(&perf_sched_events); | |
4667 | mutex_unlock(&perf_sched_mutex); | |
4668 | } | |
4669 | ||
bed5b25a AS |
4670 | /* |
4671 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4672 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4673 | * at a time, so we disallow creating events that might conflict, namely: | |
4674 | * | |
4675 | * 1) cpu-wide events in the presence of per-task events, | |
4676 | * 2) per-task events in the presence of cpu-wide events, | |
4677 | * 3) two matching events on the same context. | |
4678 | * | |
4679 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4680 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4681 | */ |
4682 | static int exclusive_event_init(struct perf_event *event) | |
4683 | { | |
4684 | struct pmu *pmu = event->pmu; | |
4685 | ||
8a58ddae | 4686 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4687 | return 0; |
4688 | ||
4689 | /* | |
4690 | * Prevent co-existence of per-task and cpu-wide events on the | |
4691 | * same exclusive pmu. | |
4692 | * | |
4693 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4694 | * events on this "exclusive" pmu, positive means there are | |
4695 | * per-task events. | |
4696 | * | |
4697 | * Since this is called in perf_event_alloc() path, event::ctx | |
4698 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4699 | * to mean "per-task event", because unlike other attach states it | |
4700 | * never gets cleared. | |
4701 | */ | |
4702 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4703 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4704 | return -EBUSY; | |
4705 | } else { | |
4706 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4707 | return -EBUSY; | |
4708 | } | |
4709 | ||
4710 | return 0; | |
4711 | } | |
4712 | ||
4713 | static void exclusive_event_destroy(struct perf_event *event) | |
4714 | { | |
4715 | struct pmu *pmu = event->pmu; | |
4716 | ||
8a58ddae | 4717 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4718 | return; |
4719 | ||
4720 | /* see comment in exclusive_event_init() */ | |
4721 | if (event->attach_state & PERF_ATTACH_TASK) | |
4722 | atomic_dec(&pmu->exclusive_cnt); | |
4723 | else | |
4724 | atomic_inc(&pmu->exclusive_cnt); | |
4725 | } | |
4726 | ||
4727 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4728 | { | |
3bf6215a | 4729 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4730 | (e1->cpu == e2->cpu || |
4731 | e1->cpu == -1 || | |
4732 | e2->cpu == -1)) | |
4733 | return true; | |
4734 | return false; | |
4735 | } | |
4736 | ||
bed5b25a AS |
4737 | static bool exclusive_event_installable(struct perf_event *event, |
4738 | struct perf_event_context *ctx) | |
4739 | { | |
4740 | struct perf_event *iter_event; | |
4741 | struct pmu *pmu = event->pmu; | |
4742 | ||
8a58ddae AS |
4743 | lockdep_assert_held(&ctx->mutex); |
4744 | ||
4745 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4746 | return true; |
4747 | ||
4748 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4749 | if (exclusive_event_match(iter_event, event)) | |
4750 | return false; | |
4751 | } | |
4752 | ||
4753 | return true; | |
4754 | } | |
4755 | ||
375637bc AS |
4756 | static void perf_addr_filters_splice(struct perf_event *event, |
4757 | struct list_head *head); | |
4758 | ||
683ede43 | 4759 | static void _free_event(struct perf_event *event) |
f1600952 | 4760 | { |
e360adbe | 4761 | irq_work_sync(&event->pending); |
925d519a | 4762 | |
4beb31f3 | 4763 | unaccount_event(event); |
9ee318a7 | 4764 | |
da97e184 JFG |
4765 | security_perf_event_free(event); |
4766 | ||
76369139 | 4767 | if (event->rb) { |
9bb5d40c PZ |
4768 | /* |
4769 | * Can happen when we close an event with re-directed output. | |
4770 | * | |
4771 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4772 | * over us; possibly making our ring_buffer_put() the last. | |
4773 | */ | |
4774 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4775 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4776 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4777 | } |
4778 | ||
e5d1367f SE |
4779 | if (is_cgroup_event(event)) |
4780 | perf_detach_cgroup(event); | |
4781 | ||
a0733e69 PZ |
4782 | if (!event->parent) { |
4783 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4784 | put_callchain_buffers(); | |
4785 | } | |
4786 | ||
4787 | perf_event_free_bpf_prog(event); | |
375637bc | 4788 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4789 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4790 | |
4791 | if (event->destroy) | |
4792 | event->destroy(event); | |
4793 | ||
1cf8dfe8 PZ |
4794 | /* |
4795 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4796 | * hw.target. | |
4797 | */ | |
621b6d2e PB |
4798 | if (event->hw.target) |
4799 | put_task_struct(event->hw.target); | |
4800 | ||
1cf8dfe8 PZ |
4801 | /* |
4802 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4803 | * all task references must be cleaned up. | |
4804 | */ | |
4805 | if (event->ctx) | |
4806 | put_ctx(event->ctx); | |
4807 | ||
62a92c8f AS |
4808 | exclusive_event_destroy(event); |
4809 | module_put(event->pmu->module); | |
a0733e69 PZ |
4810 | |
4811 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4812 | } |
4813 | ||
683ede43 PZ |
4814 | /* |
4815 | * Used to free events which have a known refcount of 1, such as in error paths | |
4816 | * where the event isn't exposed yet and inherited events. | |
4817 | */ | |
4818 | static void free_event(struct perf_event *event) | |
0793a61d | 4819 | { |
683ede43 PZ |
4820 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4821 | "unexpected event refcount: %ld; ptr=%p\n", | |
4822 | atomic_long_read(&event->refcount), event)) { | |
4823 | /* leak to avoid use-after-free */ | |
4824 | return; | |
4825 | } | |
0793a61d | 4826 | |
683ede43 | 4827 | _free_event(event); |
0793a61d TG |
4828 | } |
4829 | ||
a66a3052 | 4830 | /* |
f8697762 | 4831 | * Remove user event from the owner task. |
a66a3052 | 4832 | */ |
f8697762 | 4833 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4834 | { |
8882135b | 4835 | struct task_struct *owner; |
fb0459d7 | 4836 | |
8882135b | 4837 | rcu_read_lock(); |
8882135b | 4838 | /* |
f47c02c0 PZ |
4839 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4840 | * observe !owner it means the list deletion is complete and we can | |
4841 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4842 | * owner->perf_event_mutex. |
4843 | */ | |
506458ef | 4844 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4845 | if (owner) { |
4846 | /* | |
4847 | * Since delayed_put_task_struct() also drops the last | |
4848 | * task reference we can safely take a new reference | |
4849 | * while holding the rcu_read_lock(). | |
4850 | */ | |
4851 | get_task_struct(owner); | |
4852 | } | |
4853 | rcu_read_unlock(); | |
4854 | ||
4855 | if (owner) { | |
f63a8daa PZ |
4856 | /* |
4857 | * If we're here through perf_event_exit_task() we're already | |
4858 | * holding ctx->mutex which would be an inversion wrt. the | |
4859 | * normal lock order. | |
4860 | * | |
4861 | * However we can safely take this lock because its the child | |
4862 | * ctx->mutex. | |
4863 | */ | |
4864 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4865 | ||
8882135b PZ |
4866 | /* |
4867 | * We have to re-check the event->owner field, if it is cleared | |
4868 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4869 | * ensured they're done, and we can proceed with freeing the | |
4870 | * event. | |
4871 | */ | |
f47c02c0 | 4872 | if (event->owner) { |
8882135b | 4873 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4874 | smp_store_release(&event->owner, NULL); |
4875 | } | |
8882135b PZ |
4876 | mutex_unlock(&owner->perf_event_mutex); |
4877 | put_task_struct(owner); | |
4878 | } | |
f8697762 JO |
4879 | } |
4880 | ||
f8697762 JO |
4881 | static void put_event(struct perf_event *event) |
4882 | { | |
f8697762 JO |
4883 | if (!atomic_long_dec_and_test(&event->refcount)) |
4884 | return; | |
4885 | ||
c6e5b732 PZ |
4886 | _free_event(event); |
4887 | } | |
4888 | ||
4889 | /* | |
4890 | * Kill an event dead; while event:refcount will preserve the event | |
4891 | * object, it will not preserve its functionality. Once the last 'user' | |
4892 | * gives up the object, we'll destroy the thing. | |
4893 | */ | |
4894 | int perf_event_release_kernel(struct perf_event *event) | |
4895 | { | |
a4f4bb6d | 4896 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4897 | struct perf_event *child, *tmp; |
82d94856 | 4898 | LIST_HEAD(free_list); |
c6e5b732 | 4899 | |
a4f4bb6d PZ |
4900 | /* |
4901 | * If we got here through err_file: fput(event_file); we will not have | |
4902 | * attached to a context yet. | |
4903 | */ | |
4904 | if (!ctx) { | |
4905 | WARN_ON_ONCE(event->attach_state & | |
4906 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4907 | goto no_ctx; | |
4908 | } | |
4909 | ||
f8697762 JO |
4910 | if (!is_kernel_event(event)) |
4911 | perf_remove_from_owner(event); | |
8882135b | 4912 | |
5fa7c8ec | 4913 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4914 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4915 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4916 | |
a69b0ca4 | 4917 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4918 | /* |
d8a8cfc7 | 4919 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4920 | * anymore. |
683ede43 | 4921 | * |
a69b0ca4 PZ |
4922 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4923 | * also see this, most importantly inherit_event() which will avoid | |
4924 | * placing more children on the list. | |
683ede43 | 4925 | * |
c6e5b732 PZ |
4926 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4927 | * child events. | |
683ede43 | 4928 | */ |
a69b0ca4 PZ |
4929 | event->state = PERF_EVENT_STATE_DEAD; |
4930 | raw_spin_unlock_irq(&ctx->lock); | |
4931 | ||
4932 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4933 | |
c6e5b732 PZ |
4934 | again: |
4935 | mutex_lock(&event->child_mutex); | |
4936 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4937 | |
c6e5b732 PZ |
4938 | /* |
4939 | * Cannot change, child events are not migrated, see the | |
4940 | * comment with perf_event_ctx_lock_nested(). | |
4941 | */ | |
506458ef | 4942 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4943 | /* |
4944 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4945 | * through hoops. We start by grabbing a reference on the ctx. | |
4946 | * | |
4947 | * Since the event cannot get freed while we hold the | |
4948 | * child_mutex, the context must also exist and have a !0 | |
4949 | * reference count. | |
4950 | */ | |
4951 | get_ctx(ctx); | |
4952 | ||
4953 | /* | |
4954 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4955 | * acquire ctx::mutex without fear of it going away. Then we | |
4956 | * can re-acquire child_mutex. | |
4957 | */ | |
4958 | mutex_unlock(&event->child_mutex); | |
4959 | mutex_lock(&ctx->mutex); | |
4960 | mutex_lock(&event->child_mutex); | |
4961 | ||
4962 | /* | |
4963 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4964 | * state, if child is still the first entry, it didn't get freed | |
4965 | * and we can continue doing so. | |
4966 | */ | |
4967 | tmp = list_first_entry_or_null(&event->child_list, | |
4968 | struct perf_event, child_list); | |
4969 | if (tmp == child) { | |
4970 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4971 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4972 | /* |
4973 | * This matches the refcount bump in inherit_event(); | |
4974 | * this can't be the last reference. | |
4975 | */ | |
4976 | put_event(event); | |
4977 | } | |
4978 | ||
4979 | mutex_unlock(&event->child_mutex); | |
4980 | mutex_unlock(&ctx->mutex); | |
4981 | put_ctx(ctx); | |
4982 | goto again; | |
4983 | } | |
4984 | mutex_unlock(&event->child_mutex); | |
4985 | ||
82d94856 | 4986 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4987 | void *var = &child->ctx->refcount; |
4988 | ||
82d94856 PZ |
4989 | list_del(&child->child_list); |
4990 | free_event(child); | |
1cf8dfe8 PZ |
4991 | |
4992 | /* | |
4993 | * Wake any perf_event_free_task() waiting for this event to be | |
4994 | * freed. | |
4995 | */ | |
4996 | smp_mb(); /* pairs with wait_var_event() */ | |
4997 | wake_up_var(var); | |
82d94856 PZ |
4998 | } |
4999 | ||
a4f4bb6d PZ |
5000 | no_ctx: |
5001 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
5002 | return 0; |
5003 | } | |
5004 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
5005 | ||
8b10c5e2 PZ |
5006 | /* |
5007 | * Called when the last reference to the file is gone. | |
5008 | */ | |
a6fa941d AV |
5009 | static int perf_release(struct inode *inode, struct file *file) |
5010 | { | |
c6e5b732 | 5011 | perf_event_release_kernel(file->private_data); |
a6fa941d | 5012 | return 0; |
fb0459d7 | 5013 | } |
fb0459d7 | 5014 | |
ca0dd44c | 5015 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 5016 | { |
cdd6c482 | 5017 | struct perf_event *child; |
e53c0994 PZ |
5018 | u64 total = 0; |
5019 | ||
59ed446f PZ |
5020 | *enabled = 0; |
5021 | *running = 0; | |
5022 | ||
6f10581a | 5023 | mutex_lock(&event->child_mutex); |
01add3ea | 5024 | |
7d88962e | 5025 | (void)perf_event_read(event, false); |
01add3ea SB |
5026 | total += perf_event_count(event); |
5027 | ||
59ed446f PZ |
5028 | *enabled += event->total_time_enabled + |
5029 | atomic64_read(&event->child_total_time_enabled); | |
5030 | *running += event->total_time_running + | |
5031 | atomic64_read(&event->child_total_time_running); | |
5032 | ||
5033 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5034 | (void)perf_event_read(child, false); |
01add3ea | 5035 | total += perf_event_count(child); |
59ed446f PZ |
5036 | *enabled += child->total_time_enabled; |
5037 | *running += child->total_time_running; | |
5038 | } | |
6f10581a | 5039 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5040 | |
5041 | return total; | |
5042 | } | |
ca0dd44c PZ |
5043 | |
5044 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5045 | { | |
5046 | struct perf_event_context *ctx; | |
5047 | u64 count; | |
5048 | ||
5049 | ctx = perf_event_ctx_lock(event); | |
5050 | count = __perf_event_read_value(event, enabled, running); | |
5051 | perf_event_ctx_unlock(event, ctx); | |
5052 | ||
5053 | return count; | |
5054 | } | |
fb0459d7 | 5055 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5056 | |
7d88962e | 5057 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5058 | u64 read_format, u64 *values) |
3dab77fb | 5059 | { |
2aeb1883 | 5060 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5061 | struct perf_event *sub; |
2aeb1883 | 5062 | unsigned long flags; |
fa8c2693 | 5063 | int n = 1; /* skip @nr */ |
7d88962e | 5064 | int ret; |
f63a8daa | 5065 | |
7d88962e SB |
5066 | ret = perf_event_read(leader, true); |
5067 | if (ret) | |
5068 | return ret; | |
abf4868b | 5069 | |
a9cd8194 PZ |
5070 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5071 | ||
fa8c2693 PZ |
5072 | /* |
5073 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5074 | * will be identical to those of the leader, so we only publish one | |
5075 | * set. | |
5076 | */ | |
5077 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5078 | values[n++] += leader->total_time_enabled + | |
5079 | atomic64_read(&leader->child_total_time_enabled); | |
5080 | } | |
3dab77fb | 5081 | |
fa8c2693 PZ |
5082 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5083 | values[n++] += leader->total_time_running + | |
5084 | atomic64_read(&leader->child_total_time_running); | |
5085 | } | |
5086 | ||
5087 | /* | |
5088 | * Write {count,id} tuples for every sibling. | |
5089 | */ | |
5090 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5091 | if (read_format & PERF_FORMAT_ID) |
5092 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5093 | |
edb39592 | 5094 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5095 | values[n++] += perf_event_count(sub); |
5096 | if (read_format & PERF_FORMAT_ID) | |
5097 | values[n++] = primary_event_id(sub); | |
5098 | } | |
7d88962e | 5099 | |
2aeb1883 | 5100 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5101 | return 0; |
fa8c2693 | 5102 | } |
3dab77fb | 5103 | |
fa8c2693 PZ |
5104 | static int perf_read_group(struct perf_event *event, |
5105 | u64 read_format, char __user *buf) | |
5106 | { | |
5107 | struct perf_event *leader = event->group_leader, *child; | |
5108 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5109 | int ret; |
fa8c2693 | 5110 | u64 *values; |
3dab77fb | 5111 | |
fa8c2693 | 5112 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5113 | |
fa8c2693 PZ |
5114 | values = kzalloc(event->read_size, GFP_KERNEL); |
5115 | if (!values) | |
5116 | return -ENOMEM; | |
3dab77fb | 5117 | |
fa8c2693 PZ |
5118 | values[0] = 1 + leader->nr_siblings; |
5119 | ||
5120 | /* | |
5121 | * By locking the child_mutex of the leader we effectively | |
5122 | * lock the child list of all siblings.. XXX explain how. | |
5123 | */ | |
5124 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5125 | |
7d88962e SB |
5126 | ret = __perf_read_group_add(leader, read_format, values); |
5127 | if (ret) | |
5128 | goto unlock; | |
5129 | ||
5130 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5131 | ret = __perf_read_group_add(child, read_format, values); | |
5132 | if (ret) | |
5133 | goto unlock; | |
5134 | } | |
abf4868b | 5135 | |
fa8c2693 | 5136 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5137 | |
7d88962e | 5138 | ret = event->read_size; |
fa8c2693 PZ |
5139 | if (copy_to_user(buf, values, event->read_size)) |
5140 | ret = -EFAULT; | |
7d88962e | 5141 | goto out; |
fa8c2693 | 5142 | |
7d88962e SB |
5143 | unlock: |
5144 | mutex_unlock(&leader->child_mutex); | |
5145 | out: | |
fa8c2693 | 5146 | kfree(values); |
abf4868b | 5147 | return ret; |
3dab77fb PZ |
5148 | } |
5149 | ||
b15f495b | 5150 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5151 | u64 read_format, char __user *buf) |
5152 | { | |
59ed446f | 5153 | u64 enabled, running; |
3dab77fb PZ |
5154 | u64 values[4]; |
5155 | int n = 0; | |
5156 | ||
ca0dd44c | 5157 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5158 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5159 | values[n++] = enabled; | |
5160 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5161 | values[n++] = running; | |
3dab77fb | 5162 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5163 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5164 | |
5165 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5166 | return -EFAULT; | |
5167 | ||
5168 | return n * sizeof(u64); | |
5169 | } | |
5170 | ||
dc633982 JO |
5171 | static bool is_event_hup(struct perf_event *event) |
5172 | { | |
5173 | bool no_children; | |
5174 | ||
a69b0ca4 | 5175 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5176 | return false; |
5177 | ||
5178 | mutex_lock(&event->child_mutex); | |
5179 | no_children = list_empty(&event->child_list); | |
5180 | mutex_unlock(&event->child_mutex); | |
5181 | return no_children; | |
5182 | } | |
5183 | ||
0793a61d | 5184 | /* |
cdd6c482 | 5185 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5186 | */ |
5187 | static ssize_t | |
b15f495b | 5188 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5189 | { |
cdd6c482 | 5190 | u64 read_format = event->attr.read_format; |
3dab77fb | 5191 | int ret; |
0793a61d | 5192 | |
3b6f9e5c | 5193 | /* |
788faab7 | 5194 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5195 | * error state (i.e. because it was pinned but it couldn't be |
5196 | * scheduled on to the CPU at some point). | |
5197 | */ | |
cdd6c482 | 5198 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5199 | return 0; |
5200 | ||
c320c7b7 | 5201 | if (count < event->read_size) |
3dab77fb PZ |
5202 | return -ENOSPC; |
5203 | ||
cdd6c482 | 5204 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5205 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5206 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5207 | else |
b15f495b | 5208 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5209 | |
3dab77fb | 5210 | return ret; |
0793a61d TG |
5211 | } |
5212 | ||
0793a61d TG |
5213 | static ssize_t |
5214 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5215 | { | |
cdd6c482 | 5216 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5217 | struct perf_event_context *ctx; |
5218 | int ret; | |
0793a61d | 5219 | |
da97e184 JFG |
5220 | ret = security_perf_event_read(event); |
5221 | if (ret) | |
5222 | return ret; | |
5223 | ||
f63a8daa | 5224 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5225 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5226 | perf_event_ctx_unlock(event, ctx); |
5227 | ||
5228 | return ret; | |
0793a61d TG |
5229 | } |
5230 | ||
9dd95748 | 5231 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5232 | { |
cdd6c482 | 5233 | struct perf_event *event = file->private_data; |
56de4e8f | 5234 | struct perf_buffer *rb; |
a9a08845 | 5235 | __poll_t events = EPOLLHUP; |
c7138f37 | 5236 | |
e708d7ad | 5237 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5238 | |
dc633982 | 5239 | if (is_event_hup(event)) |
179033b3 | 5240 | return events; |
c7138f37 | 5241 | |
10c6db11 | 5242 | /* |
9bb5d40c PZ |
5243 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5244 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5245 | */ |
5246 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5247 | rb = event->rb; |
5248 | if (rb) | |
76369139 | 5249 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5250 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5251 | return events; |
5252 | } | |
5253 | ||
f63a8daa | 5254 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5255 | { |
7d88962e | 5256 | (void)perf_event_read(event, false); |
e7850595 | 5257 | local64_set(&event->count, 0); |
cdd6c482 | 5258 | perf_event_update_userpage(event); |
3df5edad PZ |
5259 | } |
5260 | ||
52ba4b0b LX |
5261 | /* Assume it's not an event with inherit set. */ |
5262 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5263 | { | |
5264 | struct perf_event_context *ctx; | |
5265 | u64 count; | |
5266 | ||
5267 | ctx = perf_event_ctx_lock(event); | |
5268 | WARN_ON_ONCE(event->attr.inherit); | |
5269 | _perf_event_disable(event); | |
5270 | count = local64_read(&event->count); | |
5271 | if (reset) | |
5272 | local64_set(&event->count, 0); | |
5273 | perf_event_ctx_unlock(event, ctx); | |
5274 | ||
5275 | return count; | |
5276 | } | |
5277 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5278 | ||
c93f7669 | 5279 | /* |
cdd6c482 IM |
5280 | * Holding the top-level event's child_mutex means that any |
5281 | * descendant process that has inherited this event will block | |
8ba289b8 | 5282 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5283 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5284 | */ |
cdd6c482 IM |
5285 | static void perf_event_for_each_child(struct perf_event *event, |
5286 | void (*func)(struct perf_event *)) | |
3df5edad | 5287 | { |
cdd6c482 | 5288 | struct perf_event *child; |
3df5edad | 5289 | |
cdd6c482 | 5290 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5291 | |
cdd6c482 IM |
5292 | mutex_lock(&event->child_mutex); |
5293 | func(event); | |
5294 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5295 | func(child); |
cdd6c482 | 5296 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5297 | } |
5298 | ||
cdd6c482 IM |
5299 | static void perf_event_for_each(struct perf_event *event, |
5300 | void (*func)(struct perf_event *)) | |
3df5edad | 5301 | { |
cdd6c482 IM |
5302 | struct perf_event_context *ctx = event->ctx; |
5303 | struct perf_event *sibling; | |
3df5edad | 5304 | |
f63a8daa PZ |
5305 | lockdep_assert_held(&ctx->mutex); |
5306 | ||
cdd6c482 | 5307 | event = event->group_leader; |
75f937f2 | 5308 | |
cdd6c482 | 5309 | perf_event_for_each_child(event, func); |
edb39592 | 5310 | for_each_sibling_event(sibling, event) |
724b6daa | 5311 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5312 | } |
5313 | ||
fae3fde6 PZ |
5314 | static void __perf_event_period(struct perf_event *event, |
5315 | struct perf_cpu_context *cpuctx, | |
5316 | struct perf_event_context *ctx, | |
5317 | void *info) | |
c7999c6f | 5318 | { |
fae3fde6 | 5319 | u64 value = *((u64 *)info); |
c7999c6f | 5320 | bool active; |
08247e31 | 5321 | |
cdd6c482 | 5322 | if (event->attr.freq) { |
cdd6c482 | 5323 | event->attr.sample_freq = value; |
08247e31 | 5324 | } else { |
cdd6c482 IM |
5325 | event->attr.sample_period = value; |
5326 | event->hw.sample_period = value; | |
08247e31 | 5327 | } |
bad7192b PZ |
5328 | |
5329 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5330 | if (active) { | |
5331 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5332 | /* |
5333 | * We could be throttled; unthrottle now to avoid the tick | |
5334 | * trying to unthrottle while we already re-started the event. | |
5335 | */ | |
5336 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5337 | event->hw.interrupts = 0; | |
5338 | perf_log_throttle(event, 1); | |
5339 | } | |
bad7192b PZ |
5340 | event->pmu->stop(event, PERF_EF_UPDATE); |
5341 | } | |
5342 | ||
5343 | local64_set(&event->hw.period_left, 0); | |
5344 | ||
5345 | if (active) { | |
5346 | event->pmu->start(event, PERF_EF_RELOAD); | |
5347 | perf_pmu_enable(ctx->pmu); | |
5348 | } | |
c7999c6f PZ |
5349 | } |
5350 | ||
81ec3f3c JO |
5351 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5352 | { | |
5353 | return event->pmu->check_period(event, value); | |
5354 | } | |
5355 | ||
3ca270fc | 5356 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5357 | { |
c7999c6f PZ |
5358 | if (!is_sampling_event(event)) |
5359 | return -EINVAL; | |
5360 | ||
c7999c6f PZ |
5361 | if (!value) |
5362 | return -EINVAL; | |
5363 | ||
5364 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5365 | return -EINVAL; | |
5366 | ||
81ec3f3c JO |
5367 | if (perf_event_check_period(event, value)) |
5368 | return -EINVAL; | |
5369 | ||
913a90bc RB |
5370 | if (!event->attr.freq && (value & (1ULL << 63))) |
5371 | return -EINVAL; | |
5372 | ||
fae3fde6 | 5373 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5374 | |
c7999c6f | 5375 | return 0; |
08247e31 PZ |
5376 | } |
5377 | ||
3ca270fc LX |
5378 | int perf_event_period(struct perf_event *event, u64 value) |
5379 | { | |
5380 | struct perf_event_context *ctx; | |
5381 | int ret; | |
5382 | ||
5383 | ctx = perf_event_ctx_lock(event); | |
5384 | ret = _perf_event_period(event, value); | |
5385 | perf_event_ctx_unlock(event, ctx); | |
5386 | ||
5387 | return ret; | |
5388 | } | |
5389 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5390 | ||
ac9721f3 PZ |
5391 | static const struct file_operations perf_fops; |
5392 | ||
2903ff01 | 5393 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5394 | { |
2903ff01 AV |
5395 | struct fd f = fdget(fd); |
5396 | if (!f.file) | |
5397 | return -EBADF; | |
ac9721f3 | 5398 | |
2903ff01 AV |
5399 | if (f.file->f_op != &perf_fops) { |
5400 | fdput(f); | |
5401 | return -EBADF; | |
ac9721f3 | 5402 | } |
2903ff01 AV |
5403 | *p = f; |
5404 | return 0; | |
ac9721f3 PZ |
5405 | } |
5406 | ||
5407 | static int perf_event_set_output(struct perf_event *event, | |
5408 | struct perf_event *output_event); | |
6fb2915d | 5409 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5410 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5411 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5412 | struct perf_event_attr *attr); | |
a4be7c27 | 5413 | |
f63a8daa | 5414 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5415 | { |
cdd6c482 | 5416 | void (*func)(struct perf_event *); |
3df5edad | 5417 | u32 flags = arg; |
d859e29f PM |
5418 | |
5419 | switch (cmd) { | |
cdd6c482 | 5420 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5421 | func = _perf_event_enable; |
d859e29f | 5422 | break; |
cdd6c482 | 5423 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5424 | func = _perf_event_disable; |
79f14641 | 5425 | break; |
cdd6c482 | 5426 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5427 | func = _perf_event_reset; |
6de6a7b9 | 5428 | break; |
3df5edad | 5429 | |
cdd6c482 | 5430 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5431 | return _perf_event_refresh(event, arg); |
08247e31 | 5432 | |
cdd6c482 | 5433 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5434 | { |
5435 | u64 value; | |
08247e31 | 5436 | |
3ca270fc LX |
5437 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5438 | return -EFAULT; | |
08247e31 | 5439 | |
3ca270fc LX |
5440 | return _perf_event_period(event, value); |
5441 | } | |
cf4957f1 JO |
5442 | case PERF_EVENT_IOC_ID: |
5443 | { | |
5444 | u64 id = primary_event_id(event); | |
5445 | ||
5446 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5447 | return -EFAULT; | |
5448 | return 0; | |
5449 | } | |
5450 | ||
cdd6c482 | 5451 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5452 | { |
ac9721f3 | 5453 | int ret; |
ac9721f3 | 5454 | if (arg != -1) { |
2903ff01 AV |
5455 | struct perf_event *output_event; |
5456 | struct fd output; | |
5457 | ret = perf_fget_light(arg, &output); | |
5458 | if (ret) | |
5459 | return ret; | |
5460 | output_event = output.file->private_data; | |
5461 | ret = perf_event_set_output(event, output_event); | |
5462 | fdput(output); | |
5463 | } else { | |
5464 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5465 | } |
ac9721f3 PZ |
5466 | return ret; |
5467 | } | |
a4be7c27 | 5468 | |
6fb2915d LZ |
5469 | case PERF_EVENT_IOC_SET_FILTER: |
5470 | return perf_event_set_filter(event, (void __user *)arg); | |
5471 | ||
2541517c AS |
5472 | case PERF_EVENT_IOC_SET_BPF: |
5473 | return perf_event_set_bpf_prog(event, arg); | |
5474 | ||
86e7972f | 5475 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5476 | struct perf_buffer *rb; |
86e7972f WN |
5477 | |
5478 | rcu_read_lock(); | |
5479 | rb = rcu_dereference(event->rb); | |
5480 | if (!rb || !rb->nr_pages) { | |
5481 | rcu_read_unlock(); | |
5482 | return -EINVAL; | |
5483 | } | |
5484 | rb_toggle_paused(rb, !!arg); | |
5485 | rcu_read_unlock(); | |
5486 | return 0; | |
5487 | } | |
f371b304 YS |
5488 | |
5489 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5490 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5491 | |
5492 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5493 | struct perf_event_attr new_attr; | |
5494 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5495 | &new_attr); | |
5496 | ||
5497 | if (err) | |
5498 | return err; | |
5499 | ||
5500 | return perf_event_modify_attr(event, &new_attr); | |
5501 | } | |
d859e29f | 5502 | default: |
3df5edad | 5503 | return -ENOTTY; |
d859e29f | 5504 | } |
3df5edad PZ |
5505 | |
5506 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5507 | perf_event_for_each(event, func); |
3df5edad | 5508 | else |
cdd6c482 | 5509 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5510 | |
5511 | return 0; | |
d859e29f PM |
5512 | } |
5513 | ||
f63a8daa PZ |
5514 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5515 | { | |
5516 | struct perf_event *event = file->private_data; | |
5517 | struct perf_event_context *ctx; | |
5518 | long ret; | |
5519 | ||
da97e184 JFG |
5520 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5521 | ret = security_perf_event_write(event); | |
5522 | if (ret) | |
5523 | return ret; | |
5524 | ||
f63a8daa PZ |
5525 | ctx = perf_event_ctx_lock(event); |
5526 | ret = _perf_ioctl(event, cmd, arg); | |
5527 | perf_event_ctx_unlock(event, ctx); | |
5528 | ||
5529 | return ret; | |
5530 | } | |
5531 | ||
b3f20785 PM |
5532 | #ifdef CONFIG_COMPAT |
5533 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5534 | unsigned long arg) | |
5535 | { | |
5536 | switch (_IOC_NR(cmd)) { | |
5537 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5538 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5539 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5540 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5541 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5542 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5543 | cmd &= ~IOCSIZE_MASK; | |
5544 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5545 | } | |
5546 | break; | |
5547 | } | |
5548 | return perf_ioctl(file, cmd, arg); | |
5549 | } | |
5550 | #else | |
5551 | # define perf_compat_ioctl NULL | |
5552 | #endif | |
5553 | ||
cdd6c482 | 5554 | int perf_event_task_enable(void) |
771d7cde | 5555 | { |
f63a8daa | 5556 | struct perf_event_context *ctx; |
cdd6c482 | 5557 | struct perf_event *event; |
771d7cde | 5558 | |
cdd6c482 | 5559 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5560 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5561 | ctx = perf_event_ctx_lock(event); | |
5562 | perf_event_for_each_child(event, _perf_event_enable); | |
5563 | perf_event_ctx_unlock(event, ctx); | |
5564 | } | |
cdd6c482 | 5565 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5566 | |
5567 | return 0; | |
5568 | } | |
5569 | ||
cdd6c482 | 5570 | int perf_event_task_disable(void) |
771d7cde | 5571 | { |
f63a8daa | 5572 | struct perf_event_context *ctx; |
cdd6c482 | 5573 | struct perf_event *event; |
771d7cde | 5574 | |
cdd6c482 | 5575 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5576 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5577 | ctx = perf_event_ctx_lock(event); | |
5578 | perf_event_for_each_child(event, _perf_event_disable); | |
5579 | perf_event_ctx_unlock(event, ctx); | |
5580 | } | |
cdd6c482 | 5581 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5582 | |
5583 | return 0; | |
5584 | } | |
5585 | ||
cdd6c482 | 5586 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5587 | { |
a4eaf7f1 PZ |
5588 | if (event->hw.state & PERF_HES_STOPPED) |
5589 | return 0; | |
5590 | ||
cdd6c482 | 5591 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5592 | return 0; |
5593 | ||
35edc2a5 | 5594 | return event->pmu->event_idx(event); |
194002b2 PZ |
5595 | } |
5596 | ||
c4794295 | 5597 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5598 | u64 *now, |
7f310a5d EM |
5599 | u64 *enabled, |
5600 | u64 *running) | |
c4794295 | 5601 | { |
e3f3541c | 5602 | u64 ctx_time; |
c4794295 | 5603 | |
e3f3541c PZ |
5604 | *now = perf_clock(); |
5605 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5606 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5607 | } |
5608 | ||
fa731587 PZ |
5609 | static void perf_event_init_userpage(struct perf_event *event) |
5610 | { | |
5611 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5612 | struct perf_buffer *rb; |
fa731587 PZ |
5613 | |
5614 | rcu_read_lock(); | |
5615 | rb = rcu_dereference(event->rb); | |
5616 | if (!rb) | |
5617 | goto unlock; | |
5618 | ||
5619 | userpg = rb->user_page; | |
5620 | ||
5621 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5622 | userpg->cap_bit0_is_deprecated = 1; | |
5623 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5624 | userpg->data_offset = PAGE_SIZE; |
5625 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5626 | |
5627 | unlock: | |
5628 | rcu_read_unlock(); | |
5629 | } | |
5630 | ||
c1317ec2 AL |
5631 | void __weak arch_perf_update_userpage( |
5632 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5633 | { |
5634 | } | |
5635 | ||
38ff667b PZ |
5636 | /* |
5637 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5638 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5639 | * code calls this from NMI context. | |
5640 | */ | |
cdd6c482 | 5641 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5642 | { |
cdd6c482 | 5643 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5644 | struct perf_buffer *rb; |
e3f3541c | 5645 | u64 enabled, running, now; |
38ff667b PZ |
5646 | |
5647 | rcu_read_lock(); | |
5ec4c599 PZ |
5648 | rb = rcu_dereference(event->rb); |
5649 | if (!rb) | |
5650 | goto unlock; | |
5651 | ||
0d641208 EM |
5652 | /* |
5653 | * compute total_time_enabled, total_time_running | |
5654 | * based on snapshot values taken when the event | |
5655 | * was last scheduled in. | |
5656 | * | |
5657 | * we cannot simply called update_context_time() | |
5658 | * because of locking issue as we can be called in | |
5659 | * NMI context | |
5660 | */ | |
e3f3541c | 5661 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5662 | |
76369139 | 5663 | userpg = rb->user_page; |
7b732a75 | 5664 | /* |
9d2dcc8f MF |
5665 | * Disable preemption to guarantee consistent time stamps are stored to |
5666 | * the user page. | |
7b732a75 PZ |
5667 | */ |
5668 | preempt_disable(); | |
37d81828 | 5669 | ++userpg->lock; |
92f22a38 | 5670 | barrier(); |
cdd6c482 | 5671 | userpg->index = perf_event_index(event); |
b5e58793 | 5672 | userpg->offset = perf_event_count(event); |
365a4038 | 5673 | if (userpg->index) |
e7850595 | 5674 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5675 | |
0d641208 | 5676 | userpg->time_enabled = enabled + |
cdd6c482 | 5677 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5678 | |
0d641208 | 5679 | userpg->time_running = running + |
cdd6c482 | 5680 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5681 | |
c1317ec2 | 5682 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5683 | |
92f22a38 | 5684 | barrier(); |
37d81828 | 5685 | ++userpg->lock; |
7b732a75 | 5686 | preempt_enable(); |
38ff667b | 5687 | unlock: |
7b732a75 | 5688 | rcu_read_unlock(); |
37d81828 | 5689 | } |
82975c46 | 5690 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5691 | |
9e3ed2d7 | 5692 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5693 | { |
11bac800 | 5694 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5695 | struct perf_buffer *rb; |
9e3ed2d7 | 5696 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5697 | |
5698 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5699 | if (vmf->pgoff == 0) | |
5700 | ret = 0; | |
5701 | return ret; | |
5702 | } | |
5703 | ||
5704 | rcu_read_lock(); | |
76369139 FW |
5705 | rb = rcu_dereference(event->rb); |
5706 | if (!rb) | |
906010b2 PZ |
5707 | goto unlock; |
5708 | ||
5709 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5710 | goto unlock; | |
5711 | ||
76369139 | 5712 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5713 | if (!vmf->page) |
5714 | goto unlock; | |
5715 | ||
5716 | get_page(vmf->page); | |
11bac800 | 5717 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5718 | vmf->page->index = vmf->pgoff; |
5719 | ||
5720 | ret = 0; | |
5721 | unlock: | |
5722 | rcu_read_unlock(); | |
5723 | ||
5724 | return ret; | |
5725 | } | |
5726 | ||
10c6db11 | 5727 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5728 | struct perf_buffer *rb) |
10c6db11 | 5729 | { |
56de4e8f | 5730 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5731 | unsigned long flags; |
5732 | ||
b69cf536 PZ |
5733 | if (event->rb) { |
5734 | /* | |
5735 | * Should be impossible, we set this when removing | |
5736 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5737 | */ | |
5738 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5739 | |
b69cf536 | 5740 | old_rb = event->rb; |
b69cf536 PZ |
5741 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5742 | list_del_rcu(&event->rb_entry); | |
5743 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5744 | |
2f993cf0 ON |
5745 | event->rcu_batches = get_state_synchronize_rcu(); |
5746 | event->rcu_pending = 1; | |
b69cf536 | 5747 | } |
10c6db11 | 5748 | |
b69cf536 | 5749 | if (rb) { |
2f993cf0 ON |
5750 | if (event->rcu_pending) { |
5751 | cond_synchronize_rcu(event->rcu_batches); | |
5752 | event->rcu_pending = 0; | |
5753 | } | |
5754 | ||
b69cf536 PZ |
5755 | spin_lock_irqsave(&rb->event_lock, flags); |
5756 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5757 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5758 | } | |
5759 | ||
767ae086 AS |
5760 | /* |
5761 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5762 | * before swizzling the event::rb pointer; if it's getting | |
5763 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5764 | * restart. See the comment in __perf_pmu_output_stop(). | |
5765 | * | |
5766 | * Data will inevitably be lost when set_output is done in | |
5767 | * mid-air, but then again, whoever does it like this is | |
5768 | * not in for the data anyway. | |
5769 | */ | |
5770 | if (has_aux(event)) | |
5771 | perf_event_stop(event, 0); | |
5772 | ||
b69cf536 PZ |
5773 | rcu_assign_pointer(event->rb, rb); |
5774 | ||
5775 | if (old_rb) { | |
5776 | ring_buffer_put(old_rb); | |
5777 | /* | |
5778 | * Since we detached before setting the new rb, so that we | |
5779 | * could attach the new rb, we could have missed a wakeup. | |
5780 | * Provide it now. | |
5781 | */ | |
5782 | wake_up_all(&event->waitq); | |
5783 | } | |
10c6db11 PZ |
5784 | } |
5785 | ||
5786 | static void ring_buffer_wakeup(struct perf_event *event) | |
5787 | { | |
56de4e8f | 5788 | struct perf_buffer *rb; |
10c6db11 PZ |
5789 | |
5790 | rcu_read_lock(); | |
5791 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5792 | if (rb) { |
5793 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5794 | wake_up_all(&event->waitq); | |
5795 | } | |
10c6db11 PZ |
5796 | rcu_read_unlock(); |
5797 | } | |
5798 | ||
56de4e8f | 5799 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5800 | { |
56de4e8f | 5801 | struct perf_buffer *rb; |
7b732a75 | 5802 | |
ac9721f3 | 5803 | rcu_read_lock(); |
76369139 FW |
5804 | rb = rcu_dereference(event->rb); |
5805 | if (rb) { | |
fecb8ed2 | 5806 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5807 | rb = NULL; |
ac9721f3 PZ |
5808 | } |
5809 | rcu_read_unlock(); | |
5810 | ||
76369139 | 5811 | return rb; |
ac9721f3 PZ |
5812 | } |
5813 | ||
56de4e8f | 5814 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5815 | { |
fecb8ed2 | 5816 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5817 | return; |
7b732a75 | 5818 | |
9bb5d40c | 5819 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5820 | |
76369139 | 5821 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5822 | } |
5823 | ||
5824 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5825 | { | |
cdd6c482 | 5826 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5827 | |
cdd6c482 | 5828 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5829 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5830 | |
45bfb2e5 PZ |
5831 | if (vma->vm_pgoff) |
5832 | atomic_inc(&event->rb->aux_mmap_count); | |
5833 | ||
1e0fb9ec | 5834 | if (event->pmu->event_mapped) |
bfe33492 | 5835 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5836 | } |
5837 | ||
95ff4ca2 AS |
5838 | static void perf_pmu_output_stop(struct perf_event *event); |
5839 | ||
9bb5d40c PZ |
5840 | /* |
5841 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5842 | * event, or through other events by use of perf_event_set_output(). | |
5843 | * | |
5844 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5845 | * the buffer here, where we still have a VM context. This means we need | |
5846 | * to detach all events redirecting to us. | |
5847 | */ | |
7b732a75 PZ |
5848 | static void perf_mmap_close(struct vm_area_struct *vma) |
5849 | { | |
cdd6c482 | 5850 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5851 | |
56de4e8f | 5852 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5853 | struct user_struct *mmap_user = rb->mmap_user; |
5854 | int mmap_locked = rb->mmap_locked; | |
5855 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5856 | |
1e0fb9ec | 5857 | if (event->pmu->event_unmapped) |
bfe33492 | 5858 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5859 | |
45bfb2e5 PZ |
5860 | /* |
5861 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5862 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5863 | * serialize with perf_mmap here. | |
5864 | */ | |
5865 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5866 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5867 | /* |
5868 | * Stop all AUX events that are writing to this buffer, | |
5869 | * so that we can free its AUX pages and corresponding PMU | |
5870 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5871 | * they won't start any more (see perf_aux_output_begin()). | |
5872 | */ | |
5873 | perf_pmu_output_stop(event); | |
5874 | ||
5875 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5876 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5877 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5878 | |
95ff4ca2 | 5879 | /* this has to be the last one */ |
45bfb2e5 | 5880 | rb_free_aux(rb); |
ca3bb3d0 | 5881 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5882 | |
45bfb2e5 PZ |
5883 | mutex_unlock(&event->mmap_mutex); |
5884 | } | |
5885 | ||
9bb5d40c PZ |
5886 | atomic_dec(&rb->mmap_count); |
5887 | ||
5888 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5889 | goto out_put; |
9bb5d40c | 5890 | |
b69cf536 | 5891 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5892 | mutex_unlock(&event->mmap_mutex); |
5893 | ||
5894 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5895 | if (atomic_read(&rb->mmap_count)) |
5896 | goto out_put; | |
ac9721f3 | 5897 | |
9bb5d40c PZ |
5898 | /* |
5899 | * No other mmap()s, detach from all other events that might redirect | |
5900 | * into the now unreachable buffer. Somewhat complicated by the | |
5901 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5902 | */ | |
5903 | again: | |
5904 | rcu_read_lock(); | |
5905 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5906 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5907 | /* | |
5908 | * This event is en-route to free_event() which will | |
5909 | * detach it and remove it from the list. | |
5910 | */ | |
5911 | continue; | |
5912 | } | |
5913 | rcu_read_unlock(); | |
789f90fc | 5914 | |
9bb5d40c PZ |
5915 | mutex_lock(&event->mmap_mutex); |
5916 | /* | |
5917 | * Check we didn't race with perf_event_set_output() which can | |
5918 | * swizzle the rb from under us while we were waiting to | |
5919 | * acquire mmap_mutex. | |
5920 | * | |
5921 | * If we find a different rb; ignore this event, a next | |
5922 | * iteration will no longer find it on the list. We have to | |
5923 | * still restart the iteration to make sure we're not now | |
5924 | * iterating the wrong list. | |
5925 | */ | |
b69cf536 PZ |
5926 | if (event->rb == rb) |
5927 | ring_buffer_attach(event, NULL); | |
5928 | ||
cdd6c482 | 5929 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5930 | put_event(event); |
ac9721f3 | 5931 | |
9bb5d40c PZ |
5932 | /* |
5933 | * Restart the iteration; either we're on the wrong list or | |
5934 | * destroyed its integrity by doing a deletion. | |
5935 | */ | |
5936 | goto again; | |
7b732a75 | 5937 | } |
9bb5d40c PZ |
5938 | rcu_read_unlock(); |
5939 | ||
5940 | /* | |
5941 | * It could be there's still a few 0-ref events on the list; they'll | |
5942 | * get cleaned up by free_event() -- they'll also still have their | |
5943 | * ref on the rb and will free it whenever they are done with it. | |
5944 | * | |
5945 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5946 | * undo the VM accounting. | |
5947 | */ | |
5948 | ||
d44248a4 SL |
5949 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5950 | &mmap_user->locked_vm); | |
70f8a3ca | 5951 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5952 | free_uid(mmap_user); |
5953 | ||
b69cf536 | 5954 | out_put: |
9bb5d40c | 5955 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5956 | } |
5957 | ||
f0f37e2f | 5958 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5959 | .open = perf_mmap_open, |
fca0c116 | 5960 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5961 | .fault = perf_mmap_fault, |
5962 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5963 | }; |
5964 | ||
5965 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5966 | { | |
cdd6c482 | 5967 | struct perf_event *event = file->private_data; |
22a4f650 | 5968 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5969 | struct user_struct *user = current_user(); |
56de4e8f | 5970 | struct perf_buffer *rb = NULL; |
22a4f650 | 5971 | unsigned long locked, lock_limit; |
7b732a75 PZ |
5972 | unsigned long vma_size; |
5973 | unsigned long nr_pages; | |
45bfb2e5 | 5974 | long user_extra = 0, extra = 0; |
d57e34fd | 5975 | int ret = 0, flags = 0; |
37d81828 | 5976 | |
c7920614 PZ |
5977 | /* |
5978 | * Don't allow mmap() of inherited per-task counters. This would | |
5979 | * create a performance issue due to all children writing to the | |
76369139 | 5980 | * same rb. |
c7920614 PZ |
5981 | */ |
5982 | if (event->cpu == -1 && event->attr.inherit) | |
5983 | return -EINVAL; | |
5984 | ||
43a21ea8 | 5985 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5986 | return -EINVAL; |
7b732a75 | 5987 | |
da97e184 JFG |
5988 | ret = security_perf_event_read(event); |
5989 | if (ret) | |
5990 | return ret; | |
5991 | ||
7b732a75 | 5992 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
5993 | |
5994 | if (vma->vm_pgoff == 0) { | |
5995 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5996 | } else { | |
5997 | /* | |
5998 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5999 | * mapped, all subsequent mappings should have the same size | |
6000 | * and offset. Must be above the normal perf buffer. | |
6001 | */ | |
6002 | u64 aux_offset, aux_size; | |
6003 | ||
6004 | if (!event->rb) | |
6005 | return -EINVAL; | |
6006 | ||
6007 | nr_pages = vma_size / PAGE_SIZE; | |
6008 | ||
6009 | mutex_lock(&event->mmap_mutex); | |
6010 | ret = -EINVAL; | |
6011 | ||
6012 | rb = event->rb; | |
6013 | if (!rb) | |
6014 | goto aux_unlock; | |
6015 | ||
6aa7de05 MR |
6016 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
6017 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
6018 | |
6019 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
6020 | goto aux_unlock; | |
6021 | ||
6022 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
6023 | goto aux_unlock; | |
6024 | ||
6025 | /* already mapped with a different offset */ | |
6026 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6027 | goto aux_unlock; | |
6028 | ||
6029 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6030 | goto aux_unlock; | |
6031 | ||
6032 | /* already mapped with a different size */ | |
6033 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6034 | goto aux_unlock; | |
6035 | ||
6036 | if (!is_power_of_2(nr_pages)) | |
6037 | goto aux_unlock; | |
6038 | ||
6039 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6040 | goto aux_unlock; | |
6041 | ||
6042 | if (rb_has_aux(rb)) { | |
6043 | atomic_inc(&rb->aux_mmap_count); | |
6044 | ret = 0; | |
6045 | goto unlock; | |
6046 | } | |
6047 | ||
6048 | atomic_set(&rb->aux_mmap_count, 1); | |
6049 | user_extra = nr_pages; | |
6050 | ||
6051 | goto accounting; | |
6052 | } | |
7b732a75 | 6053 | |
7730d865 | 6054 | /* |
76369139 | 6055 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6056 | * can do bitmasks instead of modulo. |
6057 | */ | |
2ed11312 | 6058 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6059 | return -EINVAL; |
6060 | ||
7b732a75 | 6061 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6062 | return -EINVAL; |
6063 | ||
cdd6c482 | 6064 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6065 | again: |
cdd6c482 | 6066 | mutex_lock(&event->mmap_mutex); |
76369139 | 6067 | if (event->rb) { |
9bb5d40c | 6068 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6069 | ret = -EINVAL; |
9bb5d40c PZ |
6070 | goto unlock; |
6071 | } | |
6072 | ||
6073 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6074 | /* | |
6075 | * Raced against perf_mmap_close() through | |
6076 | * perf_event_set_output(). Try again, hope for better | |
6077 | * luck. | |
6078 | */ | |
6079 | mutex_unlock(&event->mmap_mutex); | |
6080 | goto again; | |
6081 | } | |
6082 | ||
ebb3c4c4 PZ |
6083 | goto unlock; |
6084 | } | |
6085 | ||
789f90fc | 6086 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6087 | |
6088 | accounting: | |
cdd6c482 | 6089 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6090 | |
6091 | /* | |
6092 | * Increase the limit linearly with more CPUs: | |
6093 | */ | |
6094 | user_lock_limit *= num_online_cpus(); | |
6095 | ||
00346155 SL |
6096 | user_locked = atomic_long_read(&user->locked_vm); |
6097 | ||
6098 | /* | |
6099 | * sysctl_perf_event_mlock may have changed, so that | |
6100 | * user->locked_vm > user_lock_limit | |
6101 | */ | |
6102 | if (user_locked > user_lock_limit) | |
6103 | user_locked = user_lock_limit; | |
6104 | user_locked += user_extra; | |
c5078f78 | 6105 | |
c4b75479 | 6106 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6107 | /* |
6108 | * charge locked_vm until it hits user_lock_limit; | |
6109 | * charge the rest from pinned_vm | |
6110 | */ | |
789f90fc | 6111 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6112 | user_extra -= extra; |
6113 | } | |
7b732a75 | 6114 | |
78d7d407 | 6115 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6116 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6117 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6118 | |
da97e184 | 6119 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6120 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6121 | ret = -EPERM; |
6122 | goto unlock; | |
6123 | } | |
7b732a75 | 6124 | |
45bfb2e5 | 6125 | WARN_ON(!rb && event->rb); |
906010b2 | 6126 | |
d57e34fd | 6127 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6128 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6129 | |
76369139 | 6130 | if (!rb) { |
45bfb2e5 PZ |
6131 | rb = rb_alloc(nr_pages, |
6132 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6133 | event->cpu, flags); | |
26cb63ad | 6134 | |
45bfb2e5 PZ |
6135 | if (!rb) { |
6136 | ret = -ENOMEM; | |
6137 | goto unlock; | |
6138 | } | |
43a21ea8 | 6139 | |
45bfb2e5 PZ |
6140 | atomic_set(&rb->mmap_count, 1); |
6141 | rb->mmap_user = get_current_user(); | |
6142 | rb->mmap_locked = extra; | |
26cb63ad | 6143 | |
45bfb2e5 | 6144 | ring_buffer_attach(event, rb); |
ac9721f3 | 6145 | |
45bfb2e5 PZ |
6146 | perf_event_init_userpage(event); |
6147 | perf_event_update_userpage(event); | |
6148 | } else { | |
1a594131 AS |
6149 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6150 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6151 | if (!ret) |
6152 | rb->aux_mmap_locked = extra; | |
6153 | } | |
9a0f05cb | 6154 | |
ebb3c4c4 | 6155 | unlock: |
45bfb2e5 PZ |
6156 | if (!ret) { |
6157 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6158 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6159 | |
ac9721f3 | 6160 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6161 | } else if (rb) { |
6162 | atomic_dec(&rb->mmap_count); | |
6163 | } | |
6164 | aux_unlock: | |
cdd6c482 | 6165 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6166 | |
9bb5d40c PZ |
6167 | /* |
6168 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6169 | * vma. | |
6170 | */ | |
26cb63ad | 6171 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6172 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6173 | |
1e0fb9ec | 6174 | if (event->pmu->event_mapped) |
bfe33492 | 6175 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6176 | |
7b732a75 | 6177 | return ret; |
37d81828 PM |
6178 | } |
6179 | ||
3c446b3d PZ |
6180 | static int perf_fasync(int fd, struct file *filp, int on) |
6181 | { | |
496ad9aa | 6182 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6183 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6184 | int retval; |
6185 | ||
5955102c | 6186 | inode_lock(inode); |
cdd6c482 | 6187 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6188 | inode_unlock(inode); |
3c446b3d PZ |
6189 | |
6190 | if (retval < 0) | |
6191 | return retval; | |
6192 | ||
6193 | return 0; | |
6194 | } | |
6195 | ||
0793a61d | 6196 | static const struct file_operations perf_fops = { |
3326c1ce | 6197 | .llseek = no_llseek, |
0793a61d TG |
6198 | .release = perf_release, |
6199 | .read = perf_read, | |
6200 | .poll = perf_poll, | |
d859e29f | 6201 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6202 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6203 | .mmap = perf_mmap, |
3c446b3d | 6204 | .fasync = perf_fasync, |
0793a61d TG |
6205 | }; |
6206 | ||
925d519a | 6207 | /* |
cdd6c482 | 6208 | * Perf event wakeup |
925d519a PZ |
6209 | * |
6210 | * If there's data, ensure we set the poll() state and publish everything | |
6211 | * to user-space before waking everybody up. | |
6212 | */ | |
6213 | ||
fed66e2c PZ |
6214 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6215 | { | |
6216 | /* only the parent has fasync state */ | |
6217 | if (event->parent) | |
6218 | event = event->parent; | |
6219 | return &event->fasync; | |
6220 | } | |
6221 | ||
cdd6c482 | 6222 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6223 | { |
10c6db11 | 6224 | ring_buffer_wakeup(event); |
4c9e2542 | 6225 | |
cdd6c482 | 6226 | if (event->pending_kill) { |
fed66e2c | 6227 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6228 | event->pending_kill = 0; |
4c9e2542 | 6229 | } |
925d519a PZ |
6230 | } |
6231 | ||
1d54ad94 PZ |
6232 | static void perf_pending_event_disable(struct perf_event *event) |
6233 | { | |
6234 | int cpu = READ_ONCE(event->pending_disable); | |
6235 | ||
6236 | if (cpu < 0) | |
6237 | return; | |
6238 | ||
6239 | if (cpu == smp_processor_id()) { | |
6240 | WRITE_ONCE(event->pending_disable, -1); | |
6241 | perf_event_disable_local(event); | |
6242 | return; | |
6243 | } | |
6244 | ||
6245 | /* | |
6246 | * CPU-A CPU-B | |
6247 | * | |
6248 | * perf_event_disable_inatomic() | |
6249 | * @pending_disable = CPU-A; | |
6250 | * irq_work_queue(); | |
6251 | * | |
6252 | * sched-out | |
6253 | * @pending_disable = -1; | |
6254 | * | |
6255 | * sched-in | |
6256 | * perf_event_disable_inatomic() | |
6257 | * @pending_disable = CPU-B; | |
6258 | * irq_work_queue(); // FAILS | |
6259 | * | |
6260 | * irq_work_run() | |
6261 | * perf_pending_event() | |
6262 | * | |
6263 | * But the event runs on CPU-B and wants disabling there. | |
6264 | */ | |
6265 | irq_work_queue_on(&event->pending, cpu); | |
6266 | } | |
6267 | ||
e360adbe | 6268 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6269 | { |
1d54ad94 | 6270 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6271 | int rctx; |
6272 | ||
6273 | rctx = perf_swevent_get_recursion_context(); | |
6274 | /* | |
6275 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6276 | * and we won't recurse 'further'. | |
6277 | */ | |
79f14641 | 6278 | |
1d54ad94 | 6279 | perf_pending_event_disable(event); |
79f14641 | 6280 | |
cdd6c482 IM |
6281 | if (event->pending_wakeup) { |
6282 | event->pending_wakeup = 0; | |
6283 | perf_event_wakeup(event); | |
79f14641 | 6284 | } |
d525211f PZ |
6285 | |
6286 | if (rctx >= 0) | |
6287 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6288 | } |
6289 | ||
39447b38 ZY |
6290 | /* |
6291 | * We assume there is only KVM supporting the callbacks. | |
6292 | * Later on, we might change it to a list if there is | |
6293 | * another virtualization implementation supporting the callbacks. | |
6294 | */ | |
6295 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6296 | ||
6297 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6298 | { | |
6299 | perf_guest_cbs = cbs; | |
6300 | return 0; | |
6301 | } | |
6302 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6303 | ||
6304 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6305 | { | |
6306 | perf_guest_cbs = NULL; | |
6307 | return 0; | |
6308 | } | |
6309 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6310 | ||
4018994f JO |
6311 | static void |
6312 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6313 | struct pt_regs *regs, u64 mask) | |
6314 | { | |
6315 | int bit; | |
29dd3288 | 6316 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6317 | |
29dd3288 MS |
6318 | bitmap_from_u64(_mask, mask); |
6319 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6320 | u64 val; |
6321 | ||
6322 | val = perf_reg_value(regs, bit); | |
6323 | perf_output_put(handle, val); | |
6324 | } | |
6325 | } | |
6326 | ||
60e2364e | 6327 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6328 | struct pt_regs *regs, |
6329 | struct pt_regs *regs_user_copy) | |
4018994f | 6330 | { |
88a7c26a AL |
6331 | if (user_mode(regs)) { |
6332 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6333 | regs_user->regs = regs; |
085ebfe9 | 6334 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6335 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6336 | } else { |
6337 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6338 | regs_user->regs = NULL; | |
4018994f JO |
6339 | } |
6340 | } | |
6341 | ||
60e2364e SE |
6342 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6343 | struct pt_regs *regs) | |
6344 | { | |
6345 | regs_intr->regs = regs; | |
6346 | regs_intr->abi = perf_reg_abi(current); | |
6347 | } | |
6348 | ||
6349 | ||
c5ebcedb JO |
6350 | /* |
6351 | * Get remaining task size from user stack pointer. | |
6352 | * | |
6353 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6354 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6355 | * so using TASK_SIZE as limit. |
6356 | */ | |
6357 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6358 | { | |
6359 | unsigned long addr = perf_user_stack_pointer(regs); | |
6360 | ||
6361 | if (!addr || addr >= TASK_SIZE) | |
6362 | return 0; | |
6363 | ||
6364 | return TASK_SIZE - addr; | |
6365 | } | |
6366 | ||
6367 | static u16 | |
6368 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6369 | struct pt_regs *regs) | |
6370 | { | |
6371 | u64 task_size; | |
6372 | ||
6373 | /* No regs, no stack pointer, no dump. */ | |
6374 | if (!regs) | |
6375 | return 0; | |
6376 | ||
6377 | /* | |
6378 | * Check if we fit in with the requested stack size into the: | |
6379 | * - TASK_SIZE | |
6380 | * If we don't, we limit the size to the TASK_SIZE. | |
6381 | * | |
6382 | * - remaining sample size | |
6383 | * If we don't, we customize the stack size to | |
6384 | * fit in to the remaining sample size. | |
6385 | */ | |
6386 | ||
6387 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6388 | stack_size = min(stack_size, (u16) task_size); | |
6389 | ||
6390 | /* Current header size plus static size and dynamic size. */ | |
6391 | header_size += 2 * sizeof(u64); | |
6392 | ||
6393 | /* Do we fit in with the current stack dump size? */ | |
6394 | if ((u16) (header_size + stack_size) < header_size) { | |
6395 | /* | |
6396 | * If we overflow the maximum size for the sample, | |
6397 | * we customize the stack dump size to fit in. | |
6398 | */ | |
6399 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6400 | stack_size = round_up(stack_size, sizeof(u64)); | |
6401 | } | |
6402 | ||
6403 | return stack_size; | |
6404 | } | |
6405 | ||
6406 | static void | |
6407 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6408 | struct pt_regs *regs) | |
6409 | { | |
6410 | /* Case of a kernel thread, nothing to dump */ | |
6411 | if (!regs) { | |
6412 | u64 size = 0; | |
6413 | perf_output_put(handle, size); | |
6414 | } else { | |
6415 | unsigned long sp; | |
6416 | unsigned int rem; | |
6417 | u64 dyn_size; | |
02e18447 | 6418 | mm_segment_t fs; |
c5ebcedb JO |
6419 | |
6420 | /* | |
6421 | * We dump: | |
6422 | * static size | |
6423 | * - the size requested by user or the best one we can fit | |
6424 | * in to the sample max size | |
6425 | * data | |
6426 | * - user stack dump data | |
6427 | * dynamic size | |
6428 | * - the actual dumped size | |
6429 | */ | |
6430 | ||
6431 | /* Static size. */ | |
6432 | perf_output_put(handle, dump_size); | |
6433 | ||
6434 | /* Data. */ | |
6435 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6436 | fs = get_fs(); |
6437 | set_fs(USER_DS); | |
c5ebcedb | 6438 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6439 | set_fs(fs); |
c5ebcedb JO |
6440 | dyn_size = dump_size - rem; |
6441 | ||
6442 | perf_output_skip(handle, rem); | |
6443 | ||
6444 | /* Dynamic size. */ | |
6445 | perf_output_put(handle, dyn_size); | |
6446 | } | |
6447 | } | |
6448 | ||
a4faf00d AS |
6449 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6450 | struct perf_sample_data *data, | |
6451 | size_t size) | |
6452 | { | |
6453 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6454 | struct perf_buffer *rb; |
a4faf00d AS |
6455 | |
6456 | data->aux_size = 0; | |
6457 | ||
6458 | if (!sampler) | |
6459 | goto out; | |
6460 | ||
6461 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6462 | goto out; | |
6463 | ||
6464 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6465 | goto out; | |
6466 | ||
6467 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6468 | if (!rb) | |
6469 | goto out; | |
6470 | ||
6471 | /* | |
6472 | * If this is an NMI hit inside sampling code, don't take | |
6473 | * the sample. See also perf_aux_sample_output(). | |
6474 | */ | |
6475 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6476 | data->aux_size = 0; | |
6477 | } else { | |
6478 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6479 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6480 | } | |
6481 | ring_buffer_put(rb); | |
6482 | ||
6483 | out: | |
6484 | return data->aux_size; | |
6485 | } | |
6486 | ||
56de4e8f | 6487 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6488 | struct perf_event *event, |
6489 | struct perf_output_handle *handle, | |
6490 | unsigned long size) | |
6491 | { | |
6492 | unsigned long flags; | |
6493 | long ret; | |
6494 | ||
6495 | /* | |
6496 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6497 | * paths. If we start calling them in NMI context, they may race with | |
6498 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6499 | * been stopped, which is why we're using a separate callback that | |
6500 | * doesn't change the event state. | |
6501 | * | |
6502 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6503 | */ | |
6504 | local_irq_save(flags); | |
6505 | /* | |
6506 | * Guard against NMI hits inside the critical section; | |
6507 | * see also perf_prepare_sample_aux(). | |
6508 | */ | |
6509 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6510 | barrier(); | |
6511 | ||
6512 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6513 | ||
6514 | barrier(); | |
6515 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6516 | local_irq_restore(flags); | |
6517 | ||
6518 | return ret; | |
6519 | } | |
6520 | ||
6521 | static void perf_aux_sample_output(struct perf_event *event, | |
6522 | struct perf_output_handle *handle, | |
6523 | struct perf_sample_data *data) | |
6524 | { | |
6525 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6526 | struct perf_buffer *rb; |
a4faf00d | 6527 | unsigned long pad; |
a4faf00d AS |
6528 | long size; |
6529 | ||
6530 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6531 | return; | |
6532 | ||
6533 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6534 | if (!rb) | |
6535 | return; | |
6536 | ||
6537 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6538 | ||
6539 | /* | |
6540 | * An error here means that perf_output_copy() failed (returned a | |
6541 | * non-zero surplus that it didn't copy), which in its current | |
6542 | * enlightened implementation is not possible. If that changes, we'd | |
6543 | * like to know. | |
6544 | */ | |
6545 | if (WARN_ON_ONCE(size < 0)) | |
6546 | goto out_put; | |
6547 | ||
6548 | /* | |
6549 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6550 | * perf_prepare_sample_aux(), so should not be more than that. | |
6551 | */ | |
6552 | pad = data->aux_size - size; | |
6553 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6554 | pad = 8; | |
6555 | ||
6556 | if (pad) { | |
6557 | u64 zero = 0; | |
6558 | perf_output_copy(handle, &zero, pad); | |
6559 | } | |
6560 | ||
6561 | out_put: | |
6562 | ring_buffer_put(rb); | |
6563 | } | |
6564 | ||
c980d109 ACM |
6565 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6566 | struct perf_sample_data *data, | |
6567 | struct perf_event *event) | |
6844c09d ACM |
6568 | { |
6569 | u64 sample_type = event->attr.sample_type; | |
6570 | ||
6571 | data->type = sample_type; | |
6572 | header->size += event->id_header_size; | |
6573 | ||
6574 | if (sample_type & PERF_SAMPLE_TID) { | |
6575 | /* namespace issues */ | |
6576 | data->tid_entry.pid = perf_event_pid(event, current); | |
6577 | data->tid_entry.tid = perf_event_tid(event, current); | |
6578 | } | |
6579 | ||
6580 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6581 | data->time = perf_event_clock(event); |
6844c09d | 6582 | |
ff3d527c | 6583 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6584 | data->id = primary_event_id(event); |
6585 | ||
6586 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6587 | data->stream_id = event->id; | |
6588 | ||
6589 | if (sample_type & PERF_SAMPLE_CPU) { | |
6590 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6591 | data->cpu_entry.reserved = 0; | |
6592 | } | |
6593 | } | |
6594 | ||
76369139 FW |
6595 | void perf_event_header__init_id(struct perf_event_header *header, |
6596 | struct perf_sample_data *data, | |
6597 | struct perf_event *event) | |
c980d109 ACM |
6598 | { |
6599 | if (event->attr.sample_id_all) | |
6600 | __perf_event_header__init_id(header, data, event); | |
6601 | } | |
6602 | ||
6603 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6604 | struct perf_sample_data *data) | |
6605 | { | |
6606 | u64 sample_type = data->type; | |
6607 | ||
6608 | if (sample_type & PERF_SAMPLE_TID) | |
6609 | perf_output_put(handle, data->tid_entry); | |
6610 | ||
6611 | if (sample_type & PERF_SAMPLE_TIME) | |
6612 | perf_output_put(handle, data->time); | |
6613 | ||
6614 | if (sample_type & PERF_SAMPLE_ID) | |
6615 | perf_output_put(handle, data->id); | |
6616 | ||
6617 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6618 | perf_output_put(handle, data->stream_id); | |
6619 | ||
6620 | if (sample_type & PERF_SAMPLE_CPU) | |
6621 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6622 | |
6623 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6624 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6625 | } |
6626 | ||
76369139 FW |
6627 | void perf_event__output_id_sample(struct perf_event *event, |
6628 | struct perf_output_handle *handle, | |
6629 | struct perf_sample_data *sample) | |
c980d109 ACM |
6630 | { |
6631 | if (event->attr.sample_id_all) | |
6632 | __perf_event__output_id_sample(handle, sample); | |
6633 | } | |
6634 | ||
3dab77fb | 6635 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6636 | struct perf_event *event, |
6637 | u64 enabled, u64 running) | |
3dab77fb | 6638 | { |
cdd6c482 | 6639 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6640 | u64 values[4]; |
6641 | int n = 0; | |
6642 | ||
b5e58793 | 6643 | values[n++] = perf_event_count(event); |
3dab77fb | 6644 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6645 | values[n++] = enabled + |
cdd6c482 | 6646 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6647 | } |
6648 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6649 | values[n++] = running + |
cdd6c482 | 6650 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6651 | } |
6652 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6653 | values[n++] = primary_event_id(event); |
3dab77fb | 6654 | |
76369139 | 6655 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6656 | } |
6657 | ||
3dab77fb | 6658 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6659 | struct perf_event *event, |
6660 | u64 enabled, u64 running) | |
3dab77fb | 6661 | { |
cdd6c482 IM |
6662 | struct perf_event *leader = event->group_leader, *sub; |
6663 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6664 | u64 values[5]; |
6665 | int n = 0; | |
6666 | ||
6667 | values[n++] = 1 + leader->nr_siblings; | |
6668 | ||
6669 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6670 | values[n++] = enabled; |
3dab77fb PZ |
6671 | |
6672 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6673 | values[n++] = running; |
3dab77fb | 6674 | |
9e5b127d PZ |
6675 | if ((leader != event) && |
6676 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6677 | leader->pmu->read(leader); |
6678 | ||
b5e58793 | 6679 | values[n++] = perf_event_count(leader); |
3dab77fb | 6680 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6681 | values[n++] = primary_event_id(leader); |
3dab77fb | 6682 | |
76369139 | 6683 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6684 | |
edb39592 | 6685 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6686 | n = 0; |
6687 | ||
6f5ab001 JO |
6688 | if ((sub != event) && |
6689 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6690 | sub->pmu->read(sub); |
6691 | ||
b5e58793 | 6692 | values[n++] = perf_event_count(sub); |
3dab77fb | 6693 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6694 | values[n++] = primary_event_id(sub); |
3dab77fb | 6695 | |
76369139 | 6696 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6697 | } |
6698 | } | |
6699 | ||
eed01528 SE |
6700 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6701 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6702 | ||
ba5213ae PZ |
6703 | /* |
6704 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6705 | * | |
6706 | * The problem is that its both hard and excessively expensive to iterate the | |
6707 | * child list, not to mention that its impossible to IPI the children running | |
6708 | * on another CPU, from interrupt/NMI context. | |
6709 | */ | |
3dab77fb | 6710 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6711 | struct perf_event *event) |
3dab77fb | 6712 | { |
e3f3541c | 6713 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6714 | u64 read_format = event->attr.read_format; |
6715 | ||
6716 | /* | |
6717 | * compute total_time_enabled, total_time_running | |
6718 | * based on snapshot values taken when the event | |
6719 | * was last scheduled in. | |
6720 | * | |
6721 | * we cannot simply called update_context_time() | |
6722 | * because of locking issue as we are called in | |
6723 | * NMI context | |
6724 | */ | |
c4794295 | 6725 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6726 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6727 | |
cdd6c482 | 6728 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6729 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6730 | else |
eed01528 | 6731 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6732 | } |
6733 | ||
bbfd5e4f KL |
6734 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6735 | { | |
6736 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6737 | } | |
6738 | ||
5622f295 MM |
6739 | void perf_output_sample(struct perf_output_handle *handle, |
6740 | struct perf_event_header *header, | |
6741 | struct perf_sample_data *data, | |
cdd6c482 | 6742 | struct perf_event *event) |
5622f295 MM |
6743 | { |
6744 | u64 sample_type = data->type; | |
6745 | ||
6746 | perf_output_put(handle, *header); | |
6747 | ||
ff3d527c AH |
6748 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6749 | perf_output_put(handle, data->id); | |
6750 | ||
5622f295 MM |
6751 | if (sample_type & PERF_SAMPLE_IP) |
6752 | perf_output_put(handle, data->ip); | |
6753 | ||
6754 | if (sample_type & PERF_SAMPLE_TID) | |
6755 | perf_output_put(handle, data->tid_entry); | |
6756 | ||
6757 | if (sample_type & PERF_SAMPLE_TIME) | |
6758 | perf_output_put(handle, data->time); | |
6759 | ||
6760 | if (sample_type & PERF_SAMPLE_ADDR) | |
6761 | perf_output_put(handle, data->addr); | |
6762 | ||
6763 | if (sample_type & PERF_SAMPLE_ID) | |
6764 | perf_output_put(handle, data->id); | |
6765 | ||
6766 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6767 | perf_output_put(handle, data->stream_id); | |
6768 | ||
6769 | if (sample_type & PERF_SAMPLE_CPU) | |
6770 | perf_output_put(handle, data->cpu_entry); | |
6771 | ||
6772 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6773 | perf_output_put(handle, data->period); | |
6774 | ||
6775 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6776 | perf_output_read(handle, event); |
5622f295 MM |
6777 | |
6778 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6779 | int size = 1; |
5622f295 | 6780 | |
99e818cc JO |
6781 | size += data->callchain->nr; |
6782 | size *= sizeof(u64); | |
6783 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6784 | } |
6785 | ||
6786 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6787 | struct perf_raw_record *raw = data->raw; |
6788 | ||
6789 | if (raw) { | |
6790 | struct perf_raw_frag *frag = &raw->frag; | |
6791 | ||
6792 | perf_output_put(handle, raw->size); | |
6793 | do { | |
6794 | if (frag->copy) { | |
6795 | __output_custom(handle, frag->copy, | |
6796 | frag->data, frag->size); | |
6797 | } else { | |
6798 | __output_copy(handle, frag->data, | |
6799 | frag->size); | |
6800 | } | |
6801 | if (perf_raw_frag_last(frag)) | |
6802 | break; | |
6803 | frag = frag->next; | |
6804 | } while (1); | |
6805 | if (frag->pad) | |
6806 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6807 | } else { |
6808 | struct { | |
6809 | u32 size; | |
6810 | u32 data; | |
6811 | } raw = { | |
6812 | .size = sizeof(u32), | |
6813 | .data = 0, | |
6814 | }; | |
6815 | perf_output_put(handle, raw); | |
6816 | } | |
6817 | } | |
a7ac67ea | 6818 | |
bce38cd5 SE |
6819 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6820 | if (data->br_stack) { | |
6821 | size_t size; | |
6822 | ||
6823 | size = data->br_stack->nr | |
6824 | * sizeof(struct perf_branch_entry); | |
6825 | ||
6826 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6827 | if (perf_sample_save_hw_index(event)) |
6828 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6829 | perf_output_copy(handle, data->br_stack->entries, size); |
6830 | } else { | |
6831 | /* | |
6832 | * we always store at least the value of nr | |
6833 | */ | |
6834 | u64 nr = 0; | |
6835 | perf_output_put(handle, nr); | |
6836 | } | |
6837 | } | |
4018994f JO |
6838 | |
6839 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6840 | u64 abi = data->regs_user.abi; | |
6841 | ||
6842 | /* | |
6843 | * If there are no regs to dump, notice it through | |
6844 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6845 | */ | |
6846 | perf_output_put(handle, abi); | |
6847 | ||
6848 | if (abi) { | |
6849 | u64 mask = event->attr.sample_regs_user; | |
6850 | perf_output_sample_regs(handle, | |
6851 | data->regs_user.regs, | |
6852 | mask); | |
6853 | } | |
6854 | } | |
c5ebcedb | 6855 | |
a5cdd40c | 6856 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6857 | perf_output_sample_ustack(handle, |
6858 | data->stack_user_size, | |
6859 | data->regs_user.regs); | |
a5cdd40c | 6860 | } |
c3feedf2 AK |
6861 | |
6862 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6863 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6864 | |
6865 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6866 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6867 | |
fdfbbd07 AK |
6868 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6869 | perf_output_put(handle, data->txn); | |
6870 | ||
60e2364e SE |
6871 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6872 | u64 abi = data->regs_intr.abi; | |
6873 | /* | |
6874 | * If there are no regs to dump, notice it through | |
6875 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6876 | */ | |
6877 | perf_output_put(handle, abi); | |
6878 | ||
6879 | if (abi) { | |
6880 | u64 mask = event->attr.sample_regs_intr; | |
6881 | ||
6882 | perf_output_sample_regs(handle, | |
6883 | data->regs_intr.regs, | |
6884 | mask); | |
6885 | } | |
6886 | } | |
6887 | ||
fc7ce9c7 KL |
6888 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6889 | perf_output_put(handle, data->phys_addr); | |
6890 | ||
6546b19f NK |
6891 | if (sample_type & PERF_SAMPLE_CGROUP) |
6892 | perf_output_put(handle, data->cgroup); | |
6893 | ||
a4faf00d AS |
6894 | if (sample_type & PERF_SAMPLE_AUX) { |
6895 | perf_output_put(handle, data->aux_size); | |
6896 | ||
6897 | if (data->aux_size) | |
6898 | perf_aux_sample_output(event, handle, data); | |
6899 | } | |
6900 | ||
a5cdd40c PZ |
6901 | if (!event->attr.watermark) { |
6902 | int wakeup_events = event->attr.wakeup_events; | |
6903 | ||
6904 | if (wakeup_events) { | |
56de4e8f | 6905 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6906 | int events = local_inc_return(&rb->events); |
6907 | ||
6908 | if (events >= wakeup_events) { | |
6909 | local_sub(wakeup_events, &rb->events); | |
6910 | local_inc(&rb->wakeup); | |
6911 | } | |
6912 | } | |
6913 | } | |
5622f295 MM |
6914 | } |
6915 | ||
fc7ce9c7 KL |
6916 | static u64 perf_virt_to_phys(u64 virt) |
6917 | { | |
6918 | u64 phys_addr = 0; | |
6919 | struct page *p = NULL; | |
6920 | ||
6921 | if (!virt) | |
6922 | return 0; | |
6923 | ||
6924 | if (virt >= TASK_SIZE) { | |
6925 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6926 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6927 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6928 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6929 | } else { | |
6930 | /* | |
6931 | * Walking the pages tables for user address. | |
6932 | * Interrupts are disabled, so it prevents any tear down | |
6933 | * of the page tables. | |
6934 | * Try IRQ-safe __get_user_pages_fast first. | |
6935 | * If failed, leave phys_addr as 0. | |
6936 | */ | |
d3296fb3 JO |
6937 | if (current->mm != NULL) { |
6938 | pagefault_disable(); | |
6939 | if (__get_user_pages_fast(virt, 1, 0, &p) == 1) | |
6940 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6941 | pagefault_enable(); | |
6942 | } | |
fc7ce9c7 KL |
6943 | |
6944 | if (p) | |
6945 | put_page(p); | |
6946 | } | |
6947 | ||
6948 | return phys_addr; | |
6949 | } | |
6950 | ||
99e818cc JO |
6951 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6952 | ||
6cbc304f | 6953 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6954 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6955 | { | |
6956 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6957 | bool user = !event->attr.exclude_callchain_user; | |
6958 | /* Disallow cross-task user callchains. */ | |
6959 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6960 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6961 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6962 | |
6963 | if (!kernel && !user) | |
99e818cc | 6964 | return &__empty_callchain; |
8cf7e0e2 | 6965 | |
99e818cc JO |
6966 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6967 | max_stack, crosstask, true); | |
6968 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6969 | } |
6970 | ||
5622f295 MM |
6971 | void perf_prepare_sample(struct perf_event_header *header, |
6972 | struct perf_sample_data *data, | |
cdd6c482 | 6973 | struct perf_event *event, |
5622f295 | 6974 | struct pt_regs *regs) |
7b732a75 | 6975 | { |
cdd6c482 | 6976 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6977 | |
cdd6c482 | 6978 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6979 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6980 | |
6981 | header->misc = 0; | |
6982 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6983 | |
c980d109 | 6984 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6985 | |
c320c7b7 | 6986 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6987 | data->ip = perf_instruction_pointer(regs); |
6988 | ||
b23f3325 | 6989 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6990 | int size = 1; |
394ee076 | 6991 | |
6cbc304f PZ |
6992 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6993 | data->callchain = perf_callchain(event, regs); | |
6994 | ||
99e818cc | 6995 | size += data->callchain->nr; |
5622f295 MM |
6996 | |
6997 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6998 | } |
6999 | ||
3a43ce68 | 7000 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
7001 | struct perf_raw_record *raw = data->raw; |
7002 | int size; | |
7003 | ||
7004 | if (raw) { | |
7005 | struct perf_raw_frag *frag = &raw->frag; | |
7006 | u32 sum = 0; | |
7007 | ||
7008 | do { | |
7009 | sum += frag->size; | |
7010 | if (perf_raw_frag_last(frag)) | |
7011 | break; | |
7012 | frag = frag->next; | |
7013 | } while (1); | |
7014 | ||
7015 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
7016 | raw->size = size - sizeof(u32); | |
7017 | frag->pad = raw->size - sum; | |
7018 | } else { | |
7019 | size = sizeof(u64); | |
7020 | } | |
a044560c | 7021 | |
7e3f977e | 7022 | header->size += size; |
7f453c24 | 7023 | } |
bce38cd5 SE |
7024 | |
7025 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
7026 | int size = sizeof(u64); /* nr */ | |
7027 | if (data->br_stack) { | |
bbfd5e4f KL |
7028 | if (perf_sample_save_hw_index(event)) |
7029 | size += sizeof(u64); | |
7030 | ||
bce38cd5 SE |
7031 | size += data->br_stack->nr |
7032 | * sizeof(struct perf_branch_entry); | |
7033 | } | |
7034 | header->size += size; | |
7035 | } | |
4018994f | 7036 | |
2565711f | 7037 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
7038 | perf_sample_regs_user(&data->regs_user, regs, |
7039 | &data->regs_user_copy); | |
2565711f | 7040 | |
4018994f JO |
7041 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7042 | /* regs dump ABI info */ | |
7043 | int size = sizeof(u64); | |
7044 | ||
4018994f JO |
7045 | if (data->regs_user.regs) { |
7046 | u64 mask = event->attr.sample_regs_user; | |
7047 | size += hweight64(mask) * sizeof(u64); | |
7048 | } | |
7049 | ||
7050 | header->size += size; | |
7051 | } | |
c5ebcedb JO |
7052 | |
7053 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7054 | /* | |
9f014e3a | 7055 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7056 | * processed as the last one or have additional check added |
7057 | * in case new sample type is added, because we could eat | |
7058 | * up the rest of the sample size. | |
7059 | */ | |
c5ebcedb JO |
7060 | u16 stack_size = event->attr.sample_stack_user; |
7061 | u16 size = sizeof(u64); | |
7062 | ||
c5ebcedb | 7063 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7064 | data->regs_user.regs); |
c5ebcedb JO |
7065 | |
7066 | /* | |
7067 | * If there is something to dump, add space for the dump | |
7068 | * itself and for the field that tells the dynamic size, | |
7069 | * which is how many have been actually dumped. | |
7070 | */ | |
7071 | if (stack_size) | |
7072 | size += sizeof(u64) + stack_size; | |
7073 | ||
7074 | data->stack_user_size = stack_size; | |
7075 | header->size += size; | |
7076 | } | |
60e2364e SE |
7077 | |
7078 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7079 | /* regs dump ABI info */ | |
7080 | int size = sizeof(u64); | |
7081 | ||
7082 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7083 | ||
7084 | if (data->regs_intr.regs) { | |
7085 | u64 mask = event->attr.sample_regs_intr; | |
7086 | ||
7087 | size += hweight64(mask) * sizeof(u64); | |
7088 | } | |
7089 | ||
7090 | header->size += size; | |
7091 | } | |
fc7ce9c7 KL |
7092 | |
7093 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7094 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d | 7095 | |
6546b19f NK |
7096 | #ifdef CONFIG_CGROUP_PERF |
7097 | if (sample_type & PERF_SAMPLE_CGROUP) { | |
7098 | struct cgroup *cgrp; | |
7099 | ||
7100 | /* protected by RCU */ | |
7101 | cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; | |
7102 | data->cgroup = cgroup_id(cgrp); | |
7103 | } | |
7104 | #endif | |
7105 | ||
a4faf00d AS |
7106 | if (sample_type & PERF_SAMPLE_AUX) { |
7107 | u64 size; | |
7108 | ||
7109 | header->size += sizeof(u64); /* size */ | |
7110 | ||
7111 | /* | |
7112 | * Given the 16bit nature of header::size, an AUX sample can | |
7113 | * easily overflow it, what with all the preceding sample bits. | |
7114 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7115 | * per sample in total (rounded down to 8 byte boundary). | |
7116 | */ | |
7117 | size = min_t(size_t, U16_MAX - header->size, | |
7118 | event->attr.aux_sample_size); | |
7119 | size = rounddown(size, 8); | |
7120 | size = perf_prepare_sample_aux(event, data, size); | |
7121 | ||
7122 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7123 | header->size += size; | |
7124 | } | |
7125 | /* | |
7126 | * If you're adding more sample types here, you likely need to do | |
7127 | * something about the overflowing header::size, like repurpose the | |
7128 | * lowest 3 bits of size, which should be always zero at the moment. | |
7129 | * This raises a more important question, do we really need 512k sized | |
7130 | * samples and why, so good argumentation is in order for whatever you | |
7131 | * do here next. | |
7132 | */ | |
7133 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7134 | } |
7f453c24 | 7135 | |
56201969 | 7136 | static __always_inline int |
9ecda41a WN |
7137 | __perf_event_output(struct perf_event *event, |
7138 | struct perf_sample_data *data, | |
7139 | struct pt_regs *regs, | |
7140 | int (*output_begin)(struct perf_output_handle *, | |
7141 | struct perf_event *, | |
7142 | unsigned int)) | |
5622f295 MM |
7143 | { |
7144 | struct perf_output_handle handle; | |
7145 | struct perf_event_header header; | |
56201969 | 7146 | int err; |
689802b2 | 7147 | |
927c7a9e FW |
7148 | /* protect the callchain buffers */ |
7149 | rcu_read_lock(); | |
7150 | ||
cdd6c482 | 7151 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7152 | |
56201969 ACM |
7153 | err = output_begin(&handle, event, header.size); |
7154 | if (err) | |
927c7a9e | 7155 | goto exit; |
0322cd6e | 7156 | |
cdd6c482 | 7157 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7158 | |
8a057d84 | 7159 | perf_output_end(&handle); |
927c7a9e FW |
7160 | |
7161 | exit: | |
7162 | rcu_read_unlock(); | |
56201969 | 7163 | return err; |
0322cd6e PZ |
7164 | } |
7165 | ||
9ecda41a WN |
7166 | void |
7167 | perf_event_output_forward(struct perf_event *event, | |
7168 | struct perf_sample_data *data, | |
7169 | struct pt_regs *regs) | |
7170 | { | |
7171 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7172 | } | |
7173 | ||
7174 | void | |
7175 | perf_event_output_backward(struct perf_event *event, | |
7176 | struct perf_sample_data *data, | |
7177 | struct pt_regs *regs) | |
7178 | { | |
7179 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7180 | } | |
7181 | ||
56201969 | 7182 | int |
9ecda41a WN |
7183 | perf_event_output(struct perf_event *event, |
7184 | struct perf_sample_data *data, | |
7185 | struct pt_regs *regs) | |
7186 | { | |
56201969 | 7187 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7188 | } |
7189 | ||
38b200d6 | 7190 | /* |
cdd6c482 | 7191 | * read event_id |
38b200d6 PZ |
7192 | */ |
7193 | ||
7194 | struct perf_read_event { | |
7195 | struct perf_event_header header; | |
7196 | ||
7197 | u32 pid; | |
7198 | u32 tid; | |
38b200d6 PZ |
7199 | }; |
7200 | ||
7201 | static void | |
cdd6c482 | 7202 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7203 | struct task_struct *task) |
7204 | { | |
7205 | struct perf_output_handle handle; | |
c980d109 | 7206 | struct perf_sample_data sample; |
dfc65094 | 7207 | struct perf_read_event read_event = { |
38b200d6 | 7208 | .header = { |
cdd6c482 | 7209 | .type = PERF_RECORD_READ, |
38b200d6 | 7210 | .misc = 0, |
c320c7b7 | 7211 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7212 | }, |
cdd6c482 IM |
7213 | .pid = perf_event_pid(event, task), |
7214 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7215 | }; |
3dab77fb | 7216 | int ret; |
38b200d6 | 7217 | |
c980d109 | 7218 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 7219 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
7220 | if (ret) |
7221 | return; | |
7222 | ||
dfc65094 | 7223 | perf_output_put(&handle, read_event); |
cdd6c482 | 7224 | perf_output_read(&handle, event); |
c980d109 | 7225 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7226 | |
38b200d6 PZ |
7227 | perf_output_end(&handle); |
7228 | } | |
7229 | ||
aab5b71e | 7230 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7231 | |
7232 | static void | |
aab5b71e PZ |
7233 | perf_iterate_ctx(struct perf_event_context *ctx, |
7234 | perf_iterate_f output, | |
b73e4fef | 7235 | void *data, bool all) |
52d857a8 JO |
7236 | { |
7237 | struct perf_event *event; | |
7238 | ||
7239 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7240 | if (!all) { |
7241 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7242 | continue; | |
7243 | if (!event_filter_match(event)) | |
7244 | continue; | |
7245 | } | |
7246 | ||
67516844 | 7247 | output(event, data); |
52d857a8 JO |
7248 | } |
7249 | } | |
7250 | ||
aab5b71e | 7251 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7252 | { |
7253 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7254 | struct perf_event *event; | |
7255 | ||
7256 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7257 | /* |
7258 | * Skip events that are not fully formed yet; ensure that | |
7259 | * if we observe event->ctx, both event and ctx will be | |
7260 | * complete enough. See perf_install_in_context(). | |
7261 | */ | |
7262 | if (!smp_load_acquire(&event->ctx)) | |
7263 | continue; | |
7264 | ||
f2fb6bef KL |
7265 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7266 | continue; | |
7267 | if (!event_filter_match(event)) | |
7268 | continue; | |
7269 | output(event, data); | |
7270 | } | |
7271 | } | |
7272 | ||
aab5b71e PZ |
7273 | /* |
7274 | * Iterate all events that need to receive side-band events. | |
7275 | * | |
7276 | * For new callers; ensure that account_pmu_sb_event() includes | |
7277 | * your event, otherwise it might not get delivered. | |
7278 | */ | |
52d857a8 | 7279 | static void |
aab5b71e | 7280 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7281 | struct perf_event_context *task_ctx) |
7282 | { | |
52d857a8 | 7283 | struct perf_event_context *ctx; |
52d857a8 JO |
7284 | int ctxn; |
7285 | ||
aab5b71e PZ |
7286 | rcu_read_lock(); |
7287 | preempt_disable(); | |
7288 | ||
4e93ad60 | 7289 | /* |
aab5b71e PZ |
7290 | * If we have task_ctx != NULL we only notify the task context itself. |
7291 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7292 | * context. |
7293 | */ | |
7294 | if (task_ctx) { | |
aab5b71e PZ |
7295 | perf_iterate_ctx(task_ctx, output, data, false); |
7296 | goto done; | |
4e93ad60 JO |
7297 | } |
7298 | ||
aab5b71e | 7299 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7300 | |
7301 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7302 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7303 | if (ctx) | |
aab5b71e | 7304 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7305 | } |
aab5b71e | 7306 | done: |
f2fb6bef | 7307 | preempt_enable(); |
52d857a8 | 7308 | rcu_read_unlock(); |
95ff4ca2 AS |
7309 | } |
7310 | ||
375637bc AS |
7311 | /* |
7312 | * Clear all file-based filters at exec, they'll have to be | |
7313 | * re-instated when/if these objects are mmapped again. | |
7314 | */ | |
7315 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7316 | { | |
7317 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7318 | struct perf_addr_filter *filter; | |
7319 | unsigned int restart = 0, count = 0; | |
7320 | unsigned long flags; | |
7321 | ||
7322 | if (!has_addr_filter(event)) | |
7323 | return; | |
7324 | ||
7325 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7326 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7327 | if (filter->path.dentry) { |
c60f83b8 AS |
7328 | event->addr_filter_ranges[count].start = 0; |
7329 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7330 | restart++; |
7331 | } | |
7332 | ||
7333 | count++; | |
7334 | } | |
7335 | ||
7336 | if (restart) | |
7337 | event->addr_filters_gen++; | |
7338 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7339 | ||
7340 | if (restart) | |
767ae086 | 7341 | perf_event_stop(event, 1); |
375637bc AS |
7342 | } |
7343 | ||
7344 | void perf_event_exec(void) | |
7345 | { | |
7346 | struct perf_event_context *ctx; | |
7347 | int ctxn; | |
7348 | ||
7349 | rcu_read_lock(); | |
7350 | for_each_task_context_nr(ctxn) { | |
7351 | ctx = current->perf_event_ctxp[ctxn]; | |
7352 | if (!ctx) | |
7353 | continue; | |
7354 | ||
7355 | perf_event_enable_on_exec(ctxn); | |
7356 | ||
aab5b71e | 7357 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7358 | true); |
7359 | } | |
7360 | rcu_read_unlock(); | |
7361 | } | |
7362 | ||
95ff4ca2 | 7363 | struct remote_output { |
56de4e8f | 7364 | struct perf_buffer *rb; |
95ff4ca2 AS |
7365 | int err; |
7366 | }; | |
7367 | ||
7368 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7369 | { | |
7370 | struct perf_event *parent = event->parent; | |
7371 | struct remote_output *ro = data; | |
56de4e8f | 7372 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7373 | struct stop_event_data sd = { |
7374 | .event = event, | |
7375 | }; | |
95ff4ca2 AS |
7376 | |
7377 | if (!has_aux(event)) | |
7378 | return; | |
7379 | ||
7380 | if (!parent) | |
7381 | parent = event; | |
7382 | ||
7383 | /* | |
7384 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7385 | * ring-buffer, but it will be the child that's actually using it. |
7386 | * | |
7387 | * We are using event::rb to determine if the event should be stopped, | |
7388 | * however this may race with ring_buffer_attach() (through set_output), | |
7389 | * which will make us skip the event that actually needs to be stopped. | |
7390 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7391 | * its rb pointer. | |
95ff4ca2 AS |
7392 | */ |
7393 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7394 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7395 | } |
7396 | ||
7397 | static int __perf_pmu_output_stop(void *info) | |
7398 | { | |
7399 | struct perf_event *event = info; | |
f3a519e4 | 7400 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7401 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7402 | struct remote_output ro = { |
7403 | .rb = event->rb, | |
7404 | }; | |
7405 | ||
7406 | rcu_read_lock(); | |
aab5b71e | 7407 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7408 | if (cpuctx->task_ctx) |
aab5b71e | 7409 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7410 | &ro, false); |
95ff4ca2 AS |
7411 | rcu_read_unlock(); |
7412 | ||
7413 | return ro.err; | |
7414 | } | |
7415 | ||
7416 | static void perf_pmu_output_stop(struct perf_event *event) | |
7417 | { | |
7418 | struct perf_event *iter; | |
7419 | int err, cpu; | |
7420 | ||
7421 | restart: | |
7422 | rcu_read_lock(); | |
7423 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7424 | /* | |
7425 | * For per-CPU events, we need to make sure that neither they | |
7426 | * nor their children are running; for cpu==-1 events it's | |
7427 | * sufficient to stop the event itself if it's active, since | |
7428 | * it can't have children. | |
7429 | */ | |
7430 | cpu = iter->cpu; | |
7431 | if (cpu == -1) | |
7432 | cpu = READ_ONCE(iter->oncpu); | |
7433 | ||
7434 | if (cpu == -1) | |
7435 | continue; | |
7436 | ||
7437 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7438 | if (err == -EAGAIN) { | |
7439 | rcu_read_unlock(); | |
7440 | goto restart; | |
7441 | } | |
7442 | } | |
7443 | rcu_read_unlock(); | |
52d857a8 JO |
7444 | } |
7445 | ||
60313ebe | 7446 | /* |
9f498cc5 PZ |
7447 | * task tracking -- fork/exit |
7448 | * | |
13d7a241 | 7449 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7450 | */ |
7451 | ||
9f498cc5 | 7452 | struct perf_task_event { |
3a80b4a3 | 7453 | struct task_struct *task; |
cdd6c482 | 7454 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7455 | |
7456 | struct { | |
7457 | struct perf_event_header header; | |
7458 | ||
7459 | u32 pid; | |
7460 | u32 ppid; | |
9f498cc5 PZ |
7461 | u32 tid; |
7462 | u32 ptid; | |
393b2ad8 | 7463 | u64 time; |
cdd6c482 | 7464 | } event_id; |
60313ebe PZ |
7465 | }; |
7466 | ||
67516844 JO |
7467 | static int perf_event_task_match(struct perf_event *event) |
7468 | { | |
13d7a241 SE |
7469 | return event->attr.comm || event->attr.mmap || |
7470 | event->attr.mmap2 || event->attr.mmap_data || | |
7471 | event->attr.task; | |
67516844 JO |
7472 | } |
7473 | ||
cdd6c482 | 7474 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7475 | void *data) |
60313ebe | 7476 | { |
52d857a8 | 7477 | struct perf_task_event *task_event = data; |
60313ebe | 7478 | struct perf_output_handle handle; |
c980d109 | 7479 | struct perf_sample_data sample; |
9f498cc5 | 7480 | struct task_struct *task = task_event->task; |
c980d109 | 7481 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7482 | |
67516844 JO |
7483 | if (!perf_event_task_match(event)) |
7484 | return; | |
7485 | ||
c980d109 | 7486 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7487 | |
c980d109 | 7488 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7489 | task_event->event_id.header.size); |
ef60777c | 7490 | if (ret) |
c980d109 | 7491 | goto out; |
60313ebe | 7492 | |
cdd6c482 | 7493 | task_event->event_id.pid = perf_event_pid(event, task); |
cdd6c482 | 7494 | task_event->event_id.tid = perf_event_tid(event, task); |
f3bed55e IR |
7495 | |
7496 | if (task_event->event_id.header.type == PERF_RECORD_EXIT) { | |
7497 | task_event->event_id.ppid = perf_event_pid(event, | |
7498 | task->real_parent); | |
7499 | task_event->event_id.ptid = perf_event_pid(event, | |
7500 | task->real_parent); | |
7501 | } else { /* PERF_RECORD_FORK */ | |
7502 | task_event->event_id.ppid = perf_event_pid(event, current); | |
7503 | task_event->event_id.ptid = perf_event_tid(event, current); | |
7504 | } | |
9f498cc5 | 7505 | |
34f43927 PZ |
7506 | task_event->event_id.time = perf_event_clock(event); |
7507 | ||
cdd6c482 | 7508 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7509 | |
c980d109 ACM |
7510 | perf_event__output_id_sample(event, &handle, &sample); |
7511 | ||
60313ebe | 7512 | perf_output_end(&handle); |
c980d109 ACM |
7513 | out: |
7514 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7515 | } |
7516 | ||
cdd6c482 IM |
7517 | static void perf_event_task(struct task_struct *task, |
7518 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7519 | int new) |
60313ebe | 7520 | { |
9f498cc5 | 7521 | struct perf_task_event task_event; |
60313ebe | 7522 | |
cdd6c482 IM |
7523 | if (!atomic_read(&nr_comm_events) && |
7524 | !atomic_read(&nr_mmap_events) && | |
7525 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7526 | return; |
7527 | ||
9f498cc5 | 7528 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7529 | .task = task, |
7530 | .task_ctx = task_ctx, | |
cdd6c482 | 7531 | .event_id = { |
60313ebe | 7532 | .header = { |
cdd6c482 | 7533 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7534 | .misc = 0, |
cdd6c482 | 7535 | .size = sizeof(task_event.event_id), |
60313ebe | 7536 | }, |
573402db PZ |
7537 | /* .pid */ |
7538 | /* .ppid */ | |
9f498cc5 PZ |
7539 | /* .tid */ |
7540 | /* .ptid */ | |
34f43927 | 7541 | /* .time */ |
60313ebe PZ |
7542 | }, |
7543 | }; | |
7544 | ||
aab5b71e | 7545 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7546 | &task_event, |
7547 | task_ctx); | |
9f498cc5 PZ |
7548 | } |
7549 | ||
cdd6c482 | 7550 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7551 | { |
cdd6c482 | 7552 | perf_event_task(task, NULL, 1); |
e4222673 | 7553 | perf_event_namespaces(task); |
60313ebe PZ |
7554 | } |
7555 | ||
8d1b2d93 PZ |
7556 | /* |
7557 | * comm tracking | |
7558 | */ | |
7559 | ||
7560 | struct perf_comm_event { | |
22a4f650 IM |
7561 | struct task_struct *task; |
7562 | char *comm; | |
8d1b2d93 PZ |
7563 | int comm_size; |
7564 | ||
7565 | struct { | |
7566 | struct perf_event_header header; | |
7567 | ||
7568 | u32 pid; | |
7569 | u32 tid; | |
cdd6c482 | 7570 | } event_id; |
8d1b2d93 PZ |
7571 | }; |
7572 | ||
67516844 JO |
7573 | static int perf_event_comm_match(struct perf_event *event) |
7574 | { | |
7575 | return event->attr.comm; | |
7576 | } | |
7577 | ||
cdd6c482 | 7578 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7579 | void *data) |
8d1b2d93 | 7580 | { |
52d857a8 | 7581 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7582 | struct perf_output_handle handle; |
c980d109 | 7583 | struct perf_sample_data sample; |
cdd6c482 | 7584 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7585 | int ret; |
7586 | ||
67516844 JO |
7587 | if (!perf_event_comm_match(event)) |
7588 | return; | |
7589 | ||
c980d109 ACM |
7590 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7591 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7592 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7593 | |
7594 | if (ret) | |
c980d109 | 7595 | goto out; |
8d1b2d93 | 7596 | |
cdd6c482 IM |
7597 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7598 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7599 | |
cdd6c482 | 7600 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7601 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7602 | comm_event->comm_size); |
c980d109 ACM |
7603 | |
7604 | perf_event__output_id_sample(event, &handle, &sample); | |
7605 | ||
8d1b2d93 | 7606 | perf_output_end(&handle); |
c980d109 ACM |
7607 | out: |
7608 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7609 | } |
7610 | ||
cdd6c482 | 7611 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7612 | { |
413ee3b4 | 7613 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7614 | unsigned int size; |
8d1b2d93 | 7615 | |
413ee3b4 | 7616 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7617 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7618 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7619 | |
7620 | comm_event->comm = comm; | |
7621 | comm_event->comm_size = size; | |
7622 | ||
cdd6c482 | 7623 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7624 | |
aab5b71e | 7625 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7626 | comm_event, |
7627 | NULL); | |
8d1b2d93 PZ |
7628 | } |
7629 | ||
82b89778 | 7630 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7631 | { |
9ee318a7 PZ |
7632 | struct perf_comm_event comm_event; |
7633 | ||
cdd6c482 | 7634 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7635 | return; |
a63eaf34 | 7636 | |
9ee318a7 | 7637 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7638 | .task = task, |
573402db PZ |
7639 | /* .comm */ |
7640 | /* .comm_size */ | |
cdd6c482 | 7641 | .event_id = { |
573402db | 7642 | .header = { |
cdd6c482 | 7643 | .type = PERF_RECORD_COMM, |
82b89778 | 7644 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7645 | /* .size */ |
7646 | }, | |
7647 | /* .pid */ | |
7648 | /* .tid */ | |
8d1b2d93 PZ |
7649 | }, |
7650 | }; | |
7651 | ||
cdd6c482 | 7652 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7653 | } |
7654 | ||
e4222673 HB |
7655 | /* |
7656 | * namespaces tracking | |
7657 | */ | |
7658 | ||
7659 | struct perf_namespaces_event { | |
7660 | struct task_struct *task; | |
7661 | ||
7662 | struct { | |
7663 | struct perf_event_header header; | |
7664 | ||
7665 | u32 pid; | |
7666 | u32 tid; | |
7667 | u64 nr_namespaces; | |
7668 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7669 | } event_id; | |
7670 | }; | |
7671 | ||
7672 | static int perf_event_namespaces_match(struct perf_event *event) | |
7673 | { | |
7674 | return event->attr.namespaces; | |
7675 | } | |
7676 | ||
7677 | static void perf_event_namespaces_output(struct perf_event *event, | |
7678 | void *data) | |
7679 | { | |
7680 | struct perf_namespaces_event *namespaces_event = data; | |
7681 | struct perf_output_handle handle; | |
7682 | struct perf_sample_data sample; | |
34900ec5 | 7683 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7684 | int ret; |
7685 | ||
7686 | if (!perf_event_namespaces_match(event)) | |
7687 | return; | |
7688 | ||
7689 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7690 | &sample, event); | |
7691 | ret = perf_output_begin(&handle, event, | |
7692 | namespaces_event->event_id.header.size); | |
7693 | if (ret) | |
34900ec5 | 7694 | goto out; |
e4222673 HB |
7695 | |
7696 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7697 | namespaces_event->task); | |
7698 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7699 | namespaces_event->task); | |
7700 | ||
7701 | perf_output_put(&handle, namespaces_event->event_id); | |
7702 | ||
7703 | perf_event__output_id_sample(event, &handle, &sample); | |
7704 | ||
7705 | perf_output_end(&handle); | |
34900ec5 JO |
7706 | out: |
7707 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7708 | } |
7709 | ||
7710 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7711 | struct task_struct *task, | |
7712 | const struct proc_ns_operations *ns_ops) | |
7713 | { | |
7714 | struct path ns_path; | |
7715 | struct inode *ns_inode; | |
ce623f89 | 7716 | int error; |
e4222673 HB |
7717 | |
7718 | error = ns_get_path(&ns_path, task, ns_ops); | |
7719 | if (!error) { | |
7720 | ns_inode = ns_path.dentry->d_inode; | |
7721 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7722 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7723 | path_put(&ns_path); |
e4222673 HB |
7724 | } |
7725 | } | |
7726 | ||
7727 | void perf_event_namespaces(struct task_struct *task) | |
7728 | { | |
7729 | struct perf_namespaces_event namespaces_event; | |
7730 | struct perf_ns_link_info *ns_link_info; | |
7731 | ||
7732 | if (!atomic_read(&nr_namespaces_events)) | |
7733 | return; | |
7734 | ||
7735 | namespaces_event = (struct perf_namespaces_event){ | |
7736 | .task = task, | |
7737 | .event_id = { | |
7738 | .header = { | |
7739 | .type = PERF_RECORD_NAMESPACES, | |
7740 | .misc = 0, | |
7741 | .size = sizeof(namespaces_event.event_id), | |
7742 | }, | |
7743 | /* .pid */ | |
7744 | /* .tid */ | |
7745 | .nr_namespaces = NR_NAMESPACES, | |
7746 | /* .link_info[NR_NAMESPACES] */ | |
7747 | }, | |
7748 | }; | |
7749 | ||
7750 | ns_link_info = namespaces_event.event_id.link_info; | |
7751 | ||
7752 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7753 | task, &mntns_operations); | |
7754 | ||
7755 | #ifdef CONFIG_USER_NS | |
7756 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7757 | task, &userns_operations); | |
7758 | #endif | |
7759 | #ifdef CONFIG_NET_NS | |
7760 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7761 | task, &netns_operations); | |
7762 | #endif | |
7763 | #ifdef CONFIG_UTS_NS | |
7764 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7765 | task, &utsns_operations); | |
7766 | #endif | |
7767 | #ifdef CONFIG_IPC_NS | |
7768 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7769 | task, &ipcns_operations); | |
7770 | #endif | |
7771 | #ifdef CONFIG_PID_NS | |
7772 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7773 | task, &pidns_operations); | |
7774 | #endif | |
7775 | #ifdef CONFIG_CGROUPS | |
7776 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7777 | task, &cgroupns_operations); | |
7778 | #endif | |
7779 | ||
7780 | perf_iterate_sb(perf_event_namespaces_output, | |
7781 | &namespaces_event, | |
7782 | NULL); | |
7783 | } | |
7784 | ||
96aaab68 NK |
7785 | /* |
7786 | * cgroup tracking | |
7787 | */ | |
7788 | #ifdef CONFIG_CGROUP_PERF | |
7789 | ||
7790 | struct perf_cgroup_event { | |
7791 | char *path; | |
7792 | int path_size; | |
7793 | struct { | |
7794 | struct perf_event_header header; | |
7795 | u64 id; | |
7796 | char path[]; | |
7797 | } event_id; | |
7798 | }; | |
7799 | ||
7800 | static int perf_event_cgroup_match(struct perf_event *event) | |
7801 | { | |
7802 | return event->attr.cgroup; | |
7803 | } | |
7804 | ||
7805 | static void perf_event_cgroup_output(struct perf_event *event, void *data) | |
7806 | { | |
7807 | struct perf_cgroup_event *cgroup_event = data; | |
7808 | struct perf_output_handle handle; | |
7809 | struct perf_sample_data sample; | |
7810 | u16 header_size = cgroup_event->event_id.header.size; | |
7811 | int ret; | |
7812 | ||
7813 | if (!perf_event_cgroup_match(event)) | |
7814 | return; | |
7815 | ||
7816 | perf_event_header__init_id(&cgroup_event->event_id.header, | |
7817 | &sample, event); | |
7818 | ret = perf_output_begin(&handle, event, | |
7819 | cgroup_event->event_id.header.size); | |
7820 | if (ret) | |
7821 | goto out; | |
7822 | ||
7823 | perf_output_put(&handle, cgroup_event->event_id); | |
7824 | __output_copy(&handle, cgroup_event->path, cgroup_event->path_size); | |
7825 | ||
7826 | perf_event__output_id_sample(event, &handle, &sample); | |
7827 | ||
7828 | perf_output_end(&handle); | |
7829 | out: | |
7830 | cgroup_event->event_id.header.size = header_size; | |
7831 | } | |
7832 | ||
7833 | static void perf_event_cgroup(struct cgroup *cgrp) | |
7834 | { | |
7835 | struct perf_cgroup_event cgroup_event; | |
7836 | char path_enomem[16] = "//enomem"; | |
7837 | char *pathname; | |
7838 | size_t size; | |
7839 | ||
7840 | if (!atomic_read(&nr_cgroup_events)) | |
7841 | return; | |
7842 | ||
7843 | cgroup_event = (struct perf_cgroup_event){ | |
7844 | .event_id = { | |
7845 | .header = { | |
7846 | .type = PERF_RECORD_CGROUP, | |
7847 | .misc = 0, | |
7848 | .size = sizeof(cgroup_event.event_id), | |
7849 | }, | |
7850 | .id = cgroup_id(cgrp), | |
7851 | }, | |
7852 | }; | |
7853 | ||
7854 | pathname = kmalloc(PATH_MAX, GFP_KERNEL); | |
7855 | if (pathname == NULL) { | |
7856 | cgroup_event.path = path_enomem; | |
7857 | } else { | |
7858 | /* just to be sure to have enough space for alignment */ | |
7859 | cgroup_path(cgrp, pathname, PATH_MAX - sizeof(u64)); | |
7860 | cgroup_event.path = pathname; | |
7861 | } | |
7862 | ||
7863 | /* | |
7864 | * Since our buffer works in 8 byte units we need to align our string | |
7865 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7866 | * zero'd out to avoid leaking random bits to userspace. | |
7867 | */ | |
7868 | size = strlen(cgroup_event.path) + 1; | |
7869 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7870 | cgroup_event.path[size++] = '\0'; | |
7871 | ||
7872 | cgroup_event.event_id.header.size += size; | |
7873 | cgroup_event.path_size = size; | |
7874 | ||
7875 | perf_iterate_sb(perf_event_cgroup_output, | |
7876 | &cgroup_event, | |
7877 | NULL); | |
7878 | ||
7879 | kfree(pathname); | |
7880 | } | |
7881 | ||
7882 | #endif | |
7883 | ||
0a4a9391 PZ |
7884 | /* |
7885 | * mmap tracking | |
7886 | */ | |
7887 | ||
7888 | struct perf_mmap_event { | |
089dd79d PZ |
7889 | struct vm_area_struct *vma; |
7890 | ||
7891 | const char *file_name; | |
7892 | int file_size; | |
13d7a241 SE |
7893 | int maj, min; |
7894 | u64 ino; | |
7895 | u64 ino_generation; | |
f972eb63 | 7896 | u32 prot, flags; |
0a4a9391 PZ |
7897 | |
7898 | struct { | |
7899 | struct perf_event_header header; | |
7900 | ||
7901 | u32 pid; | |
7902 | u32 tid; | |
7903 | u64 start; | |
7904 | u64 len; | |
7905 | u64 pgoff; | |
cdd6c482 | 7906 | } event_id; |
0a4a9391 PZ |
7907 | }; |
7908 | ||
67516844 JO |
7909 | static int perf_event_mmap_match(struct perf_event *event, |
7910 | void *data) | |
7911 | { | |
7912 | struct perf_mmap_event *mmap_event = data; | |
7913 | struct vm_area_struct *vma = mmap_event->vma; | |
7914 | int executable = vma->vm_flags & VM_EXEC; | |
7915 | ||
7916 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7917 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7918 | } |
7919 | ||
cdd6c482 | 7920 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7921 | void *data) |
0a4a9391 | 7922 | { |
52d857a8 | 7923 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7924 | struct perf_output_handle handle; |
c980d109 | 7925 | struct perf_sample_data sample; |
cdd6c482 | 7926 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7927 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7928 | int ret; |
0a4a9391 | 7929 | |
67516844 JO |
7930 | if (!perf_event_mmap_match(event, data)) |
7931 | return; | |
7932 | ||
13d7a241 SE |
7933 | if (event->attr.mmap2) { |
7934 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7935 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7936 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7937 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7938 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7939 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7940 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7941 | } |
7942 | ||
c980d109 ACM |
7943 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7944 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7945 | mmap_event->event_id.header.size); |
0a4a9391 | 7946 | if (ret) |
c980d109 | 7947 | goto out; |
0a4a9391 | 7948 | |
cdd6c482 IM |
7949 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7950 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7951 | |
cdd6c482 | 7952 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7953 | |
7954 | if (event->attr.mmap2) { | |
7955 | perf_output_put(&handle, mmap_event->maj); | |
7956 | perf_output_put(&handle, mmap_event->min); | |
7957 | perf_output_put(&handle, mmap_event->ino); | |
7958 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7959 | perf_output_put(&handle, mmap_event->prot); |
7960 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7961 | } |
7962 | ||
76369139 | 7963 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7964 | mmap_event->file_size); |
c980d109 ACM |
7965 | |
7966 | perf_event__output_id_sample(event, &handle, &sample); | |
7967 | ||
78d613eb | 7968 | perf_output_end(&handle); |
c980d109 ACM |
7969 | out: |
7970 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7971 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7972 | } |
7973 | ||
cdd6c482 | 7974 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7975 | { |
089dd79d PZ |
7976 | struct vm_area_struct *vma = mmap_event->vma; |
7977 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7978 | int maj = 0, min = 0; |
7979 | u64 ino = 0, gen = 0; | |
f972eb63 | 7980 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7981 | unsigned int size; |
7982 | char tmp[16]; | |
7983 | char *buf = NULL; | |
2c42cfbf | 7984 | char *name; |
413ee3b4 | 7985 | |
0b3589be PZ |
7986 | if (vma->vm_flags & VM_READ) |
7987 | prot |= PROT_READ; | |
7988 | if (vma->vm_flags & VM_WRITE) | |
7989 | prot |= PROT_WRITE; | |
7990 | if (vma->vm_flags & VM_EXEC) | |
7991 | prot |= PROT_EXEC; | |
7992 | ||
7993 | if (vma->vm_flags & VM_MAYSHARE) | |
7994 | flags = MAP_SHARED; | |
7995 | else | |
7996 | flags = MAP_PRIVATE; | |
7997 | ||
7998 | if (vma->vm_flags & VM_DENYWRITE) | |
7999 | flags |= MAP_DENYWRITE; | |
8000 | if (vma->vm_flags & VM_MAYEXEC) | |
8001 | flags |= MAP_EXECUTABLE; | |
8002 | if (vma->vm_flags & VM_LOCKED) | |
8003 | flags |= MAP_LOCKED; | |
03911132 | 8004 | if (is_vm_hugetlb_page(vma)) |
0b3589be PZ |
8005 | flags |= MAP_HUGETLB; |
8006 | ||
0a4a9391 | 8007 | if (file) { |
13d7a241 SE |
8008 | struct inode *inode; |
8009 | dev_t dev; | |
3ea2f2b9 | 8010 | |
2c42cfbf | 8011 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 8012 | if (!buf) { |
c7e548b4 ON |
8013 | name = "//enomem"; |
8014 | goto cpy_name; | |
0a4a9391 | 8015 | } |
413ee3b4 | 8016 | /* |
3ea2f2b9 | 8017 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
8018 | * need to add enough zero bytes after the string to handle |
8019 | * the 64bit alignment we do later. | |
8020 | */ | |
9bf39ab2 | 8021 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 8022 | if (IS_ERR(name)) { |
c7e548b4 ON |
8023 | name = "//toolong"; |
8024 | goto cpy_name; | |
0a4a9391 | 8025 | } |
13d7a241 SE |
8026 | inode = file_inode(vma->vm_file); |
8027 | dev = inode->i_sb->s_dev; | |
8028 | ino = inode->i_ino; | |
8029 | gen = inode->i_generation; | |
8030 | maj = MAJOR(dev); | |
8031 | min = MINOR(dev); | |
f972eb63 | 8032 | |
c7e548b4 | 8033 | goto got_name; |
0a4a9391 | 8034 | } else { |
fbe26abe JO |
8035 | if (vma->vm_ops && vma->vm_ops->name) { |
8036 | name = (char *) vma->vm_ops->name(vma); | |
8037 | if (name) | |
8038 | goto cpy_name; | |
8039 | } | |
8040 | ||
2c42cfbf | 8041 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
8042 | if (name) |
8043 | goto cpy_name; | |
089dd79d | 8044 | |
32c5fb7e | 8045 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 8046 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
8047 | name = "[heap]"; |
8048 | goto cpy_name; | |
32c5fb7e ON |
8049 | } |
8050 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 8051 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
8052 | name = "[stack]"; |
8053 | goto cpy_name; | |
089dd79d PZ |
8054 | } |
8055 | ||
c7e548b4 ON |
8056 | name = "//anon"; |
8057 | goto cpy_name; | |
0a4a9391 PZ |
8058 | } |
8059 | ||
c7e548b4 ON |
8060 | cpy_name: |
8061 | strlcpy(tmp, name, sizeof(tmp)); | |
8062 | name = tmp; | |
0a4a9391 | 8063 | got_name: |
2c42cfbf PZ |
8064 | /* |
8065 | * Since our buffer works in 8 byte units we need to align our string | |
8066 | * size to a multiple of 8. However, we must guarantee the tail end is | |
8067 | * zero'd out to avoid leaking random bits to userspace. | |
8068 | */ | |
8069 | size = strlen(name)+1; | |
8070 | while (!IS_ALIGNED(size, sizeof(u64))) | |
8071 | name[size++] = '\0'; | |
0a4a9391 PZ |
8072 | |
8073 | mmap_event->file_name = name; | |
8074 | mmap_event->file_size = size; | |
13d7a241 SE |
8075 | mmap_event->maj = maj; |
8076 | mmap_event->min = min; | |
8077 | mmap_event->ino = ino; | |
8078 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
8079 | mmap_event->prot = prot; |
8080 | mmap_event->flags = flags; | |
0a4a9391 | 8081 | |
2fe85427 SE |
8082 | if (!(vma->vm_flags & VM_EXEC)) |
8083 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
8084 | ||
cdd6c482 | 8085 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 8086 | |
aab5b71e | 8087 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
8088 | mmap_event, |
8089 | NULL); | |
665c2142 | 8090 | |
0a4a9391 PZ |
8091 | kfree(buf); |
8092 | } | |
8093 | ||
375637bc AS |
8094 | /* |
8095 | * Check whether inode and address range match filter criteria. | |
8096 | */ | |
8097 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
8098 | struct file *file, unsigned long offset, | |
8099 | unsigned long size) | |
8100 | { | |
7f635ff1 MP |
8101 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
8102 | if (!filter->path.dentry) | |
8103 | return false; | |
8104 | ||
9511bce9 | 8105 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
8106 | return false; |
8107 | ||
8108 | if (filter->offset > offset + size) | |
8109 | return false; | |
8110 | ||
8111 | if (filter->offset + filter->size < offset) | |
8112 | return false; | |
8113 | ||
8114 | return true; | |
8115 | } | |
8116 | ||
c60f83b8 AS |
8117 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
8118 | struct vm_area_struct *vma, | |
8119 | struct perf_addr_filter_range *fr) | |
8120 | { | |
8121 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8122 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8123 | struct file *file = vma->vm_file; | |
8124 | ||
8125 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8126 | return false; | |
8127 | ||
8128 | if (filter->offset < off) { | |
8129 | fr->start = vma->vm_start; | |
8130 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
8131 | } else { | |
8132 | fr->start = vma->vm_start + filter->offset - off; | |
8133 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
8134 | } | |
8135 | ||
8136 | return true; | |
8137 | } | |
8138 | ||
375637bc AS |
8139 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
8140 | { | |
8141 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8142 | struct vm_area_struct *vma = data; | |
375637bc AS |
8143 | struct perf_addr_filter *filter; |
8144 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 8145 | unsigned long flags; |
375637bc AS |
8146 | |
8147 | if (!has_addr_filter(event)) | |
8148 | return; | |
8149 | ||
c60f83b8 | 8150 | if (!vma->vm_file) |
375637bc AS |
8151 | return; |
8152 | ||
8153 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8154 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8155 | if (perf_addr_filter_vma_adjust(filter, vma, |
8156 | &event->addr_filter_ranges[count])) | |
375637bc | 8157 | restart++; |
375637bc AS |
8158 | |
8159 | count++; | |
8160 | } | |
8161 | ||
8162 | if (restart) | |
8163 | event->addr_filters_gen++; | |
8164 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8165 | ||
8166 | if (restart) | |
767ae086 | 8167 | perf_event_stop(event, 1); |
375637bc AS |
8168 | } |
8169 | ||
8170 | /* | |
8171 | * Adjust all task's events' filters to the new vma | |
8172 | */ | |
8173 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8174 | { | |
8175 | struct perf_event_context *ctx; | |
8176 | int ctxn; | |
8177 | ||
12b40a23 MP |
8178 | /* |
8179 | * Data tracing isn't supported yet and as such there is no need | |
8180 | * to keep track of anything that isn't related to executable code: | |
8181 | */ | |
8182 | if (!(vma->vm_flags & VM_EXEC)) | |
8183 | return; | |
8184 | ||
375637bc AS |
8185 | rcu_read_lock(); |
8186 | for_each_task_context_nr(ctxn) { | |
8187 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8188 | if (!ctx) | |
8189 | continue; | |
8190 | ||
aab5b71e | 8191 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8192 | } |
8193 | rcu_read_unlock(); | |
8194 | } | |
8195 | ||
3af9e859 | 8196 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8197 | { |
9ee318a7 PZ |
8198 | struct perf_mmap_event mmap_event; |
8199 | ||
cdd6c482 | 8200 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8201 | return; |
8202 | ||
8203 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8204 | .vma = vma, |
573402db PZ |
8205 | /* .file_name */ |
8206 | /* .file_size */ | |
cdd6c482 | 8207 | .event_id = { |
573402db | 8208 | .header = { |
cdd6c482 | 8209 | .type = PERF_RECORD_MMAP, |
39447b38 | 8210 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8211 | /* .size */ |
8212 | }, | |
8213 | /* .pid */ | |
8214 | /* .tid */ | |
089dd79d PZ |
8215 | .start = vma->vm_start, |
8216 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8217 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8218 | }, |
13d7a241 SE |
8219 | /* .maj (attr_mmap2 only) */ |
8220 | /* .min (attr_mmap2 only) */ | |
8221 | /* .ino (attr_mmap2 only) */ | |
8222 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8223 | /* .prot (attr_mmap2 only) */ |
8224 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8225 | }; |
8226 | ||
375637bc | 8227 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8228 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8229 | } |
8230 | ||
68db7e98 AS |
8231 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8232 | unsigned long size, u64 flags) | |
8233 | { | |
8234 | struct perf_output_handle handle; | |
8235 | struct perf_sample_data sample; | |
8236 | struct perf_aux_event { | |
8237 | struct perf_event_header header; | |
8238 | u64 offset; | |
8239 | u64 size; | |
8240 | u64 flags; | |
8241 | } rec = { | |
8242 | .header = { | |
8243 | .type = PERF_RECORD_AUX, | |
8244 | .misc = 0, | |
8245 | .size = sizeof(rec), | |
8246 | }, | |
8247 | .offset = head, | |
8248 | .size = size, | |
8249 | .flags = flags, | |
8250 | }; | |
8251 | int ret; | |
8252 | ||
8253 | perf_event_header__init_id(&rec.header, &sample, event); | |
8254 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8255 | ||
8256 | if (ret) | |
8257 | return; | |
8258 | ||
8259 | perf_output_put(&handle, rec); | |
8260 | perf_event__output_id_sample(event, &handle, &sample); | |
8261 | ||
8262 | perf_output_end(&handle); | |
8263 | } | |
8264 | ||
f38b0dbb KL |
8265 | /* |
8266 | * Lost/dropped samples logging | |
8267 | */ | |
8268 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8269 | { | |
8270 | struct perf_output_handle handle; | |
8271 | struct perf_sample_data sample; | |
8272 | int ret; | |
8273 | ||
8274 | struct { | |
8275 | struct perf_event_header header; | |
8276 | u64 lost; | |
8277 | } lost_samples_event = { | |
8278 | .header = { | |
8279 | .type = PERF_RECORD_LOST_SAMPLES, | |
8280 | .misc = 0, | |
8281 | .size = sizeof(lost_samples_event), | |
8282 | }, | |
8283 | .lost = lost, | |
8284 | }; | |
8285 | ||
8286 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8287 | ||
8288 | ret = perf_output_begin(&handle, event, | |
8289 | lost_samples_event.header.size); | |
8290 | if (ret) | |
8291 | return; | |
8292 | ||
8293 | perf_output_put(&handle, lost_samples_event); | |
8294 | perf_event__output_id_sample(event, &handle, &sample); | |
8295 | perf_output_end(&handle); | |
8296 | } | |
8297 | ||
45ac1403 AH |
8298 | /* |
8299 | * context_switch tracking | |
8300 | */ | |
8301 | ||
8302 | struct perf_switch_event { | |
8303 | struct task_struct *task; | |
8304 | struct task_struct *next_prev; | |
8305 | ||
8306 | struct { | |
8307 | struct perf_event_header header; | |
8308 | u32 next_prev_pid; | |
8309 | u32 next_prev_tid; | |
8310 | } event_id; | |
8311 | }; | |
8312 | ||
8313 | static int perf_event_switch_match(struct perf_event *event) | |
8314 | { | |
8315 | return event->attr.context_switch; | |
8316 | } | |
8317 | ||
8318 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8319 | { | |
8320 | struct perf_switch_event *se = data; | |
8321 | struct perf_output_handle handle; | |
8322 | struct perf_sample_data sample; | |
8323 | int ret; | |
8324 | ||
8325 | if (!perf_event_switch_match(event)) | |
8326 | return; | |
8327 | ||
8328 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8329 | if (event->ctx->task) { | |
8330 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8331 | se->event_id.header.size = sizeof(se->event_id.header); | |
8332 | } else { | |
8333 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8334 | se->event_id.header.size = sizeof(se->event_id); | |
8335 | se->event_id.next_prev_pid = | |
8336 | perf_event_pid(event, se->next_prev); | |
8337 | se->event_id.next_prev_tid = | |
8338 | perf_event_tid(event, se->next_prev); | |
8339 | } | |
8340 | ||
8341 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8342 | ||
8343 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
8344 | if (ret) | |
8345 | return; | |
8346 | ||
8347 | if (event->ctx->task) | |
8348 | perf_output_put(&handle, se->event_id.header); | |
8349 | else | |
8350 | perf_output_put(&handle, se->event_id); | |
8351 | ||
8352 | perf_event__output_id_sample(event, &handle, &sample); | |
8353 | ||
8354 | perf_output_end(&handle); | |
8355 | } | |
8356 | ||
8357 | static void perf_event_switch(struct task_struct *task, | |
8358 | struct task_struct *next_prev, bool sched_in) | |
8359 | { | |
8360 | struct perf_switch_event switch_event; | |
8361 | ||
8362 | /* N.B. caller checks nr_switch_events != 0 */ | |
8363 | ||
8364 | switch_event = (struct perf_switch_event){ | |
8365 | .task = task, | |
8366 | .next_prev = next_prev, | |
8367 | .event_id = { | |
8368 | .header = { | |
8369 | /* .type */ | |
8370 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8371 | /* .size */ | |
8372 | }, | |
8373 | /* .next_prev_pid */ | |
8374 | /* .next_prev_tid */ | |
8375 | }, | |
8376 | }; | |
8377 | ||
101592b4 AB |
8378 | if (!sched_in && task->state == TASK_RUNNING) |
8379 | switch_event.event_id.header.misc |= | |
8380 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8381 | ||
aab5b71e | 8382 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8383 | &switch_event, |
8384 | NULL); | |
8385 | } | |
8386 | ||
a78ac325 PZ |
8387 | /* |
8388 | * IRQ throttle logging | |
8389 | */ | |
8390 | ||
cdd6c482 | 8391 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8392 | { |
8393 | struct perf_output_handle handle; | |
c980d109 | 8394 | struct perf_sample_data sample; |
a78ac325 PZ |
8395 | int ret; |
8396 | ||
8397 | struct { | |
8398 | struct perf_event_header header; | |
8399 | u64 time; | |
cca3f454 | 8400 | u64 id; |
7f453c24 | 8401 | u64 stream_id; |
a78ac325 PZ |
8402 | } throttle_event = { |
8403 | .header = { | |
cdd6c482 | 8404 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8405 | .misc = 0, |
8406 | .size = sizeof(throttle_event), | |
8407 | }, | |
34f43927 | 8408 | .time = perf_event_clock(event), |
cdd6c482 IM |
8409 | .id = primary_event_id(event), |
8410 | .stream_id = event->id, | |
a78ac325 PZ |
8411 | }; |
8412 | ||
966ee4d6 | 8413 | if (enable) |
cdd6c482 | 8414 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8415 | |
c980d109 ACM |
8416 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8417 | ||
8418 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 8419 | throttle_event.header.size); |
a78ac325 PZ |
8420 | if (ret) |
8421 | return; | |
8422 | ||
8423 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8424 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8425 | perf_output_end(&handle); |
8426 | } | |
8427 | ||
76193a94 SL |
8428 | /* |
8429 | * ksymbol register/unregister tracking | |
8430 | */ | |
8431 | ||
8432 | struct perf_ksymbol_event { | |
8433 | const char *name; | |
8434 | int name_len; | |
8435 | struct { | |
8436 | struct perf_event_header header; | |
8437 | u64 addr; | |
8438 | u32 len; | |
8439 | u16 ksym_type; | |
8440 | u16 flags; | |
8441 | } event_id; | |
8442 | }; | |
8443 | ||
8444 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8445 | { | |
8446 | return event->attr.ksymbol; | |
8447 | } | |
8448 | ||
8449 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8450 | { | |
8451 | struct perf_ksymbol_event *ksymbol_event = data; | |
8452 | struct perf_output_handle handle; | |
8453 | struct perf_sample_data sample; | |
8454 | int ret; | |
8455 | ||
8456 | if (!perf_event_ksymbol_match(event)) | |
8457 | return; | |
8458 | ||
8459 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8460 | &sample, event); | |
8461 | ret = perf_output_begin(&handle, event, | |
8462 | ksymbol_event->event_id.header.size); | |
8463 | if (ret) | |
8464 | return; | |
8465 | ||
8466 | perf_output_put(&handle, ksymbol_event->event_id); | |
8467 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8468 | perf_event__output_id_sample(event, &handle, &sample); | |
8469 | ||
8470 | perf_output_end(&handle); | |
8471 | } | |
8472 | ||
8473 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8474 | const char *sym) | |
8475 | { | |
8476 | struct perf_ksymbol_event ksymbol_event; | |
8477 | char name[KSYM_NAME_LEN]; | |
8478 | u16 flags = 0; | |
8479 | int name_len; | |
8480 | ||
8481 | if (!atomic_read(&nr_ksymbol_events)) | |
8482 | return; | |
8483 | ||
8484 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8485 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8486 | goto err; | |
8487 | ||
8488 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8489 | name_len = strlen(name) + 1; | |
8490 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8491 | name[name_len++] = '\0'; | |
8492 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8493 | ||
8494 | if (unregister) | |
8495 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8496 | ||
8497 | ksymbol_event = (struct perf_ksymbol_event){ | |
8498 | .name = name, | |
8499 | .name_len = name_len, | |
8500 | .event_id = { | |
8501 | .header = { | |
8502 | .type = PERF_RECORD_KSYMBOL, | |
8503 | .size = sizeof(ksymbol_event.event_id) + | |
8504 | name_len, | |
8505 | }, | |
8506 | .addr = addr, | |
8507 | .len = len, | |
8508 | .ksym_type = ksym_type, | |
8509 | .flags = flags, | |
8510 | }, | |
8511 | }; | |
8512 | ||
8513 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8514 | return; | |
8515 | err: | |
8516 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8517 | } | |
8518 | ||
6ee52e2a SL |
8519 | /* |
8520 | * bpf program load/unload tracking | |
8521 | */ | |
8522 | ||
8523 | struct perf_bpf_event { | |
8524 | struct bpf_prog *prog; | |
8525 | struct { | |
8526 | struct perf_event_header header; | |
8527 | u16 type; | |
8528 | u16 flags; | |
8529 | u32 id; | |
8530 | u8 tag[BPF_TAG_SIZE]; | |
8531 | } event_id; | |
8532 | }; | |
8533 | ||
8534 | static int perf_event_bpf_match(struct perf_event *event) | |
8535 | { | |
8536 | return event->attr.bpf_event; | |
8537 | } | |
8538 | ||
8539 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8540 | { | |
8541 | struct perf_bpf_event *bpf_event = data; | |
8542 | struct perf_output_handle handle; | |
8543 | struct perf_sample_data sample; | |
8544 | int ret; | |
8545 | ||
8546 | if (!perf_event_bpf_match(event)) | |
8547 | return; | |
8548 | ||
8549 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8550 | &sample, event); | |
8551 | ret = perf_output_begin(&handle, event, | |
8552 | bpf_event->event_id.header.size); | |
8553 | if (ret) | |
8554 | return; | |
8555 | ||
8556 | perf_output_put(&handle, bpf_event->event_id); | |
8557 | perf_event__output_id_sample(event, &handle, &sample); | |
8558 | ||
8559 | perf_output_end(&handle); | |
8560 | } | |
8561 | ||
8562 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8563 | enum perf_bpf_event_type type) | |
8564 | { | |
8565 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
6ee52e2a SL |
8566 | int i; |
8567 | ||
8568 | if (prog->aux->func_cnt == 0) { | |
6ee52e2a SL |
8569 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, |
8570 | (u64)(unsigned long)prog->bpf_func, | |
bfea9a85 JO |
8571 | prog->jited_len, unregister, |
8572 | prog->aux->ksym.name); | |
6ee52e2a SL |
8573 | } else { |
8574 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8575 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8576 | ||
6ee52e2a SL |
8577 | perf_event_ksymbol( |
8578 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8579 | (u64)(unsigned long)subprog->bpf_func, | |
bfea9a85 JO |
8580 | subprog->jited_len, unregister, |
8581 | prog->aux->ksym.name); | |
6ee52e2a SL |
8582 | } |
8583 | } | |
8584 | } | |
8585 | ||
8586 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8587 | enum perf_bpf_event_type type, | |
8588 | u16 flags) | |
8589 | { | |
8590 | struct perf_bpf_event bpf_event; | |
8591 | ||
8592 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8593 | type >= PERF_BPF_EVENT_MAX) | |
8594 | return; | |
8595 | ||
8596 | switch (type) { | |
8597 | case PERF_BPF_EVENT_PROG_LOAD: | |
8598 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8599 | if (atomic_read(&nr_ksymbol_events)) | |
8600 | perf_event_bpf_emit_ksymbols(prog, type); | |
8601 | break; | |
8602 | default: | |
8603 | break; | |
8604 | } | |
8605 | ||
8606 | if (!atomic_read(&nr_bpf_events)) | |
8607 | return; | |
8608 | ||
8609 | bpf_event = (struct perf_bpf_event){ | |
8610 | .prog = prog, | |
8611 | .event_id = { | |
8612 | .header = { | |
8613 | .type = PERF_RECORD_BPF_EVENT, | |
8614 | .size = sizeof(bpf_event.event_id), | |
8615 | }, | |
8616 | .type = type, | |
8617 | .flags = flags, | |
8618 | .id = prog->aux->id, | |
8619 | }, | |
8620 | }; | |
8621 | ||
8622 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8623 | ||
8624 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8625 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8626 | } | |
8627 | ||
8d4e6c4c AS |
8628 | void perf_event_itrace_started(struct perf_event *event) |
8629 | { | |
8630 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8631 | } | |
8632 | ||
ec0d7729 AS |
8633 | static void perf_log_itrace_start(struct perf_event *event) |
8634 | { | |
8635 | struct perf_output_handle handle; | |
8636 | struct perf_sample_data sample; | |
8637 | struct perf_aux_event { | |
8638 | struct perf_event_header header; | |
8639 | u32 pid; | |
8640 | u32 tid; | |
8641 | } rec; | |
8642 | int ret; | |
8643 | ||
8644 | if (event->parent) | |
8645 | event = event->parent; | |
8646 | ||
8647 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8648 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8649 | return; |
8650 | ||
ec0d7729 AS |
8651 | rec.header.type = PERF_RECORD_ITRACE_START; |
8652 | rec.header.misc = 0; | |
8653 | rec.header.size = sizeof(rec); | |
8654 | rec.pid = perf_event_pid(event, current); | |
8655 | rec.tid = perf_event_tid(event, current); | |
8656 | ||
8657 | perf_event_header__init_id(&rec.header, &sample, event); | |
8658 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8659 | ||
8660 | if (ret) | |
8661 | return; | |
8662 | ||
8663 | perf_output_put(&handle, rec); | |
8664 | perf_event__output_id_sample(event, &handle, &sample); | |
8665 | ||
8666 | perf_output_end(&handle); | |
8667 | } | |
8668 | ||
475113d9 JO |
8669 | static int |
8670 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8671 | { |
cdd6c482 | 8672 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8673 | int ret = 0; |
475113d9 | 8674 | u64 seq; |
96398826 | 8675 | |
e050e3f0 SE |
8676 | seq = __this_cpu_read(perf_throttled_seq); |
8677 | if (seq != hwc->interrupts_seq) { | |
8678 | hwc->interrupts_seq = seq; | |
8679 | hwc->interrupts = 1; | |
8680 | } else { | |
8681 | hwc->interrupts++; | |
8682 | if (unlikely(throttle | |
8683 | && hwc->interrupts >= max_samples_per_tick)) { | |
8684 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8685 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8686 | hwc->interrupts = MAX_INTERRUPTS; |
8687 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8688 | ret = 1; |
8689 | } | |
e050e3f0 | 8690 | } |
60db5e09 | 8691 | |
cdd6c482 | 8692 | if (event->attr.freq) { |
def0a9b2 | 8693 | u64 now = perf_clock(); |
abd50713 | 8694 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8695 | |
abd50713 | 8696 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8697 | |
abd50713 | 8698 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8699 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8700 | } |
8701 | ||
475113d9 JO |
8702 | return ret; |
8703 | } | |
8704 | ||
8705 | int perf_event_account_interrupt(struct perf_event *event) | |
8706 | { | |
8707 | return __perf_event_account_interrupt(event, 1); | |
8708 | } | |
8709 | ||
8710 | /* | |
8711 | * Generic event overflow handling, sampling. | |
8712 | */ | |
8713 | ||
8714 | static int __perf_event_overflow(struct perf_event *event, | |
8715 | int throttle, struct perf_sample_data *data, | |
8716 | struct pt_regs *regs) | |
8717 | { | |
8718 | int events = atomic_read(&event->event_limit); | |
8719 | int ret = 0; | |
8720 | ||
8721 | /* | |
8722 | * Non-sampling counters might still use the PMI to fold short | |
8723 | * hardware counters, ignore those. | |
8724 | */ | |
8725 | if (unlikely(!is_sampling_event(event))) | |
8726 | return 0; | |
8727 | ||
8728 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8729 | |
2023b359 PZ |
8730 | /* |
8731 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8732 | * events |
2023b359 PZ |
8733 | */ |
8734 | ||
cdd6c482 IM |
8735 | event->pending_kill = POLL_IN; |
8736 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8737 | ret = 1; |
cdd6c482 | 8738 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8739 | |
8740 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8741 | } |
8742 | ||
aa6a5f3c | 8743 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8744 | |
fed66e2c | 8745 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8746 | event->pending_wakeup = 1; |
8747 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8748 | } |
8749 | ||
79f14641 | 8750 | return ret; |
f6c7d5fe PZ |
8751 | } |
8752 | ||
a8b0ca17 | 8753 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8754 | struct perf_sample_data *data, |
8755 | struct pt_regs *regs) | |
850bc73f | 8756 | { |
a8b0ca17 | 8757 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8758 | } |
8759 | ||
15dbf27c | 8760 | /* |
cdd6c482 | 8761 | * Generic software event infrastructure |
15dbf27c PZ |
8762 | */ |
8763 | ||
b28ab83c PZ |
8764 | struct swevent_htable { |
8765 | struct swevent_hlist *swevent_hlist; | |
8766 | struct mutex hlist_mutex; | |
8767 | int hlist_refcount; | |
8768 | ||
8769 | /* Recursion avoidance in each contexts */ | |
8770 | int recursion[PERF_NR_CONTEXTS]; | |
8771 | }; | |
8772 | ||
8773 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8774 | ||
7b4b6658 | 8775 | /* |
cdd6c482 IM |
8776 | * We directly increment event->count and keep a second value in |
8777 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8778 | * is kept in the range [-sample_period, 0] so that we can use the |
8779 | * sign as trigger. | |
8780 | */ | |
8781 | ||
ab573844 | 8782 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8783 | { |
cdd6c482 | 8784 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8785 | u64 period = hwc->last_period; |
8786 | u64 nr, offset; | |
8787 | s64 old, val; | |
8788 | ||
8789 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8790 | |
8791 | again: | |
e7850595 | 8792 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8793 | if (val < 0) |
8794 | return 0; | |
15dbf27c | 8795 | |
7b4b6658 PZ |
8796 | nr = div64_u64(period + val, period); |
8797 | offset = nr * period; | |
8798 | val -= offset; | |
e7850595 | 8799 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8800 | goto again; |
15dbf27c | 8801 | |
7b4b6658 | 8802 | return nr; |
15dbf27c PZ |
8803 | } |
8804 | ||
0cff784a | 8805 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8806 | struct perf_sample_data *data, |
5622f295 | 8807 | struct pt_regs *regs) |
15dbf27c | 8808 | { |
cdd6c482 | 8809 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8810 | int throttle = 0; |
15dbf27c | 8811 | |
0cff784a PZ |
8812 | if (!overflow) |
8813 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8814 | |
7b4b6658 PZ |
8815 | if (hwc->interrupts == MAX_INTERRUPTS) |
8816 | return; | |
15dbf27c | 8817 | |
7b4b6658 | 8818 | for (; overflow; overflow--) { |
a8b0ca17 | 8819 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8820 | data, regs)) { |
7b4b6658 PZ |
8821 | /* |
8822 | * We inhibit the overflow from happening when | |
8823 | * hwc->interrupts == MAX_INTERRUPTS. | |
8824 | */ | |
8825 | break; | |
8826 | } | |
cf450a73 | 8827 | throttle = 1; |
7b4b6658 | 8828 | } |
15dbf27c PZ |
8829 | } |
8830 | ||
a4eaf7f1 | 8831 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8832 | struct perf_sample_data *data, |
5622f295 | 8833 | struct pt_regs *regs) |
7b4b6658 | 8834 | { |
cdd6c482 | 8835 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8836 | |
e7850595 | 8837 | local64_add(nr, &event->count); |
d6d020e9 | 8838 | |
0cff784a PZ |
8839 | if (!regs) |
8840 | return; | |
8841 | ||
6c7e550f | 8842 | if (!is_sampling_event(event)) |
7b4b6658 | 8843 | return; |
d6d020e9 | 8844 | |
5d81e5cf AV |
8845 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8846 | data->period = nr; | |
8847 | return perf_swevent_overflow(event, 1, data, regs); | |
8848 | } else | |
8849 | data->period = event->hw.last_period; | |
8850 | ||
0cff784a | 8851 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8852 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8853 | |
e7850595 | 8854 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8855 | return; |
df1a132b | 8856 | |
a8b0ca17 | 8857 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8858 | } |
8859 | ||
f5ffe02e FW |
8860 | static int perf_exclude_event(struct perf_event *event, |
8861 | struct pt_regs *regs) | |
8862 | { | |
a4eaf7f1 | 8863 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8864 | return 1; |
a4eaf7f1 | 8865 | |
f5ffe02e FW |
8866 | if (regs) { |
8867 | if (event->attr.exclude_user && user_mode(regs)) | |
8868 | return 1; | |
8869 | ||
8870 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8871 | return 1; | |
8872 | } | |
8873 | ||
8874 | return 0; | |
8875 | } | |
8876 | ||
cdd6c482 | 8877 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8878 | enum perf_type_id type, |
6fb2915d LZ |
8879 | u32 event_id, |
8880 | struct perf_sample_data *data, | |
8881 | struct pt_regs *regs) | |
15dbf27c | 8882 | { |
cdd6c482 | 8883 | if (event->attr.type != type) |
a21ca2ca | 8884 | return 0; |
f5ffe02e | 8885 | |
cdd6c482 | 8886 | if (event->attr.config != event_id) |
15dbf27c PZ |
8887 | return 0; |
8888 | ||
f5ffe02e FW |
8889 | if (perf_exclude_event(event, regs)) |
8890 | return 0; | |
15dbf27c PZ |
8891 | |
8892 | return 1; | |
8893 | } | |
8894 | ||
76e1d904 FW |
8895 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8896 | { | |
8897 | u64 val = event_id | (type << 32); | |
8898 | ||
8899 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8900 | } | |
8901 | ||
49f135ed FW |
8902 | static inline struct hlist_head * |
8903 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8904 | { |
49f135ed FW |
8905 | u64 hash = swevent_hash(type, event_id); |
8906 | ||
8907 | return &hlist->heads[hash]; | |
8908 | } | |
76e1d904 | 8909 | |
49f135ed FW |
8910 | /* For the read side: events when they trigger */ |
8911 | static inline struct hlist_head * | |
b28ab83c | 8912 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8913 | { |
8914 | struct swevent_hlist *hlist; | |
76e1d904 | 8915 | |
b28ab83c | 8916 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8917 | if (!hlist) |
8918 | return NULL; | |
8919 | ||
49f135ed FW |
8920 | return __find_swevent_head(hlist, type, event_id); |
8921 | } | |
8922 | ||
8923 | /* For the event head insertion and removal in the hlist */ | |
8924 | static inline struct hlist_head * | |
b28ab83c | 8925 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8926 | { |
8927 | struct swevent_hlist *hlist; | |
8928 | u32 event_id = event->attr.config; | |
8929 | u64 type = event->attr.type; | |
8930 | ||
8931 | /* | |
8932 | * Event scheduling is always serialized against hlist allocation | |
8933 | * and release. Which makes the protected version suitable here. | |
8934 | * The context lock guarantees that. | |
8935 | */ | |
b28ab83c | 8936 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8937 | lockdep_is_held(&event->ctx->lock)); |
8938 | if (!hlist) | |
8939 | return NULL; | |
8940 | ||
8941 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8942 | } |
8943 | ||
8944 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8945 | u64 nr, |
76e1d904 FW |
8946 | struct perf_sample_data *data, |
8947 | struct pt_regs *regs) | |
15dbf27c | 8948 | { |
4a32fea9 | 8949 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8950 | struct perf_event *event; |
76e1d904 | 8951 | struct hlist_head *head; |
15dbf27c | 8952 | |
76e1d904 | 8953 | rcu_read_lock(); |
b28ab83c | 8954 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8955 | if (!head) |
8956 | goto end; | |
8957 | ||
b67bfe0d | 8958 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8959 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8960 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8961 | } |
76e1d904 FW |
8962 | end: |
8963 | rcu_read_unlock(); | |
15dbf27c PZ |
8964 | } |
8965 | ||
86038c5e PZI |
8966 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8967 | ||
4ed7c92d | 8968 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8969 | { |
4a32fea9 | 8970 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8971 | |
b28ab83c | 8972 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8973 | } |
645e8cc0 | 8974 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8975 | |
98b5c2c6 | 8976 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8977 | { |
4a32fea9 | 8978 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8979 | |
b28ab83c | 8980 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8981 | } |
15dbf27c | 8982 | |
86038c5e | 8983 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8984 | { |
a4234bfc | 8985 | struct perf_sample_data data; |
4ed7c92d | 8986 | |
86038c5e | 8987 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8988 | return; |
a4234bfc | 8989 | |
fd0d000b | 8990 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8991 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8992 | } |
8993 | ||
8994 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8995 | { | |
8996 | int rctx; | |
8997 | ||
8998 | preempt_disable_notrace(); | |
8999 | rctx = perf_swevent_get_recursion_context(); | |
9000 | if (unlikely(rctx < 0)) | |
9001 | goto fail; | |
9002 | ||
9003 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
9004 | |
9005 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 9006 | fail: |
1c024eca | 9007 | preempt_enable_notrace(); |
b8e83514 PZ |
9008 | } |
9009 | ||
cdd6c482 | 9010 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 9011 | { |
15dbf27c PZ |
9012 | } |
9013 | ||
a4eaf7f1 | 9014 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 9015 | { |
4a32fea9 | 9016 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 9017 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
9018 | struct hlist_head *head; |
9019 | ||
6c7e550f | 9020 | if (is_sampling_event(event)) { |
7b4b6658 | 9021 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 9022 | perf_swevent_set_period(event); |
7b4b6658 | 9023 | } |
76e1d904 | 9024 | |
a4eaf7f1 PZ |
9025 | hwc->state = !(flags & PERF_EF_START); |
9026 | ||
b28ab83c | 9027 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 9028 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
9029 | return -EINVAL; |
9030 | ||
9031 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 9032 | perf_event_update_userpage(event); |
76e1d904 | 9033 | |
15dbf27c PZ |
9034 | return 0; |
9035 | } | |
9036 | ||
a4eaf7f1 | 9037 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 9038 | { |
76e1d904 | 9039 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
9040 | } |
9041 | ||
a4eaf7f1 | 9042 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 9043 | { |
a4eaf7f1 | 9044 | event->hw.state = 0; |
d6d020e9 | 9045 | } |
aa9c4c0f | 9046 | |
a4eaf7f1 | 9047 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 9048 | { |
a4eaf7f1 | 9049 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
9050 | } |
9051 | ||
49f135ed FW |
9052 | /* Deref the hlist from the update side */ |
9053 | static inline struct swevent_hlist * | |
b28ab83c | 9054 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 9055 | { |
b28ab83c PZ |
9056 | return rcu_dereference_protected(swhash->swevent_hlist, |
9057 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
9058 | } |
9059 | ||
b28ab83c | 9060 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 9061 | { |
b28ab83c | 9062 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 9063 | |
49f135ed | 9064 | if (!hlist) |
76e1d904 FW |
9065 | return; |
9066 | ||
70691d4a | 9067 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 9068 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
9069 | } |
9070 | ||
3b364d7b | 9071 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 9072 | { |
b28ab83c | 9073 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 9074 | |
b28ab83c | 9075 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 9076 | |
b28ab83c PZ |
9077 | if (!--swhash->hlist_refcount) |
9078 | swevent_hlist_release(swhash); | |
76e1d904 | 9079 | |
b28ab83c | 9080 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9081 | } |
9082 | ||
3b364d7b | 9083 | static void swevent_hlist_put(void) |
76e1d904 FW |
9084 | { |
9085 | int cpu; | |
9086 | ||
76e1d904 | 9087 | for_each_possible_cpu(cpu) |
3b364d7b | 9088 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
9089 | } |
9090 | ||
3b364d7b | 9091 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 9092 | { |
b28ab83c | 9093 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
9094 | int err = 0; |
9095 | ||
b28ab83c | 9096 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
9097 | if (!swevent_hlist_deref(swhash) && |
9098 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
9099 | struct swevent_hlist *hlist; |
9100 | ||
9101 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
9102 | if (!hlist) { | |
9103 | err = -ENOMEM; | |
9104 | goto exit; | |
9105 | } | |
b28ab83c | 9106 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 9107 | } |
b28ab83c | 9108 | swhash->hlist_refcount++; |
9ed6060d | 9109 | exit: |
b28ab83c | 9110 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
9111 | |
9112 | return err; | |
9113 | } | |
9114 | ||
3b364d7b | 9115 | static int swevent_hlist_get(void) |
76e1d904 | 9116 | { |
3b364d7b | 9117 | int err, cpu, failed_cpu; |
76e1d904 | 9118 | |
a63fbed7 | 9119 | mutex_lock(&pmus_lock); |
76e1d904 | 9120 | for_each_possible_cpu(cpu) { |
3b364d7b | 9121 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
9122 | if (err) { |
9123 | failed_cpu = cpu; | |
9124 | goto fail; | |
9125 | } | |
9126 | } | |
a63fbed7 | 9127 | mutex_unlock(&pmus_lock); |
76e1d904 | 9128 | return 0; |
9ed6060d | 9129 | fail: |
76e1d904 FW |
9130 | for_each_possible_cpu(cpu) { |
9131 | if (cpu == failed_cpu) | |
9132 | break; | |
3b364d7b | 9133 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 9134 | } |
a63fbed7 | 9135 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
9136 | return err; |
9137 | } | |
9138 | ||
c5905afb | 9139 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 9140 | |
b0a873eb PZ |
9141 | static void sw_perf_event_destroy(struct perf_event *event) |
9142 | { | |
9143 | u64 event_id = event->attr.config; | |
95476b64 | 9144 | |
b0a873eb PZ |
9145 | WARN_ON(event->parent); |
9146 | ||
c5905afb | 9147 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9148 | swevent_hlist_put(); |
b0a873eb PZ |
9149 | } |
9150 | ||
9151 | static int perf_swevent_init(struct perf_event *event) | |
9152 | { | |
8176cced | 9153 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9154 | |
9155 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9156 | return -ENOENT; | |
9157 | ||
2481c5fa SE |
9158 | /* |
9159 | * no branch sampling for software events | |
9160 | */ | |
9161 | if (has_branch_stack(event)) | |
9162 | return -EOPNOTSUPP; | |
9163 | ||
b0a873eb PZ |
9164 | switch (event_id) { |
9165 | case PERF_COUNT_SW_CPU_CLOCK: | |
9166 | case PERF_COUNT_SW_TASK_CLOCK: | |
9167 | return -ENOENT; | |
9168 | ||
9169 | default: | |
9170 | break; | |
9171 | } | |
9172 | ||
ce677831 | 9173 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9174 | return -ENOENT; |
9175 | ||
9176 | if (!event->parent) { | |
9177 | int err; | |
9178 | ||
3b364d7b | 9179 | err = swevent_hlist_get(); |
b0a873eb PZ |
9180 | if (err) |
9181 | return err; | |
9182 | ||
c5905afb | 9183 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9184 | event->destroy = sw_perf_event_destroy; |
9185 | } | |
9186 | ||
9187 | return 0; | |
9188 | } | |
9189 | ||
9190 | static struct pmu perf_swevent = { | |
89a1e187 | 9191 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9192 | |
34f43927 PZ |
9193 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9194 | ||
b0a873eb | 9195 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9196 | .add = perf_swevent_add, |
9197 | .del = perf_swevent_del, | |
9198 | .start = perf_swevent_start, | |
9199 | .stop = perf_swevent_stop, | |
1c024eca | 9200 | .read = perf_swevent_read, |
1c024eca PZ |
9201 | }; |
9202 | ||
b0a873eb PZ |
9203 | #ifdef CONFIG_EVENT_TRACING |
9204 | ||
1c024eca PZ |
9205 | static int perf_tp_filter_match(struct perf_event *event, |
9206 | struct perf_sample_data *data) | |
9207 | { | |
7e3f977e | 9208 | void *record = data->raw->frag.data; |
1c024eca | 9209 | |
b71b437e PZ |
9210 | /* only top level events have filters set */ |
9211 | if (event->parent) | |
9212 | event = event->parent; | |
9213 | ||
1c024eca PZ |
9214 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9215 | return 1; | |
9216 | return 0; | |
9217 | } | |
9218 | ||
9219 | static int perf_tp_event_match(struct perf_event *event, | |
9220 | struct perf_sample_data *data, | |
9221 | struct pt_regs *regs) | |
9222 | { | |
a0f7d0f7 FW |
9223 | if (event->hw.state & PERF_HES_STOPPED) |
9224 | return 0; | |
580d607c | 9225 | /* |
9fd2e48b | 9226 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9227 | */ |
9fd2e48b | 9228 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9229 | return 0; |
9230 | ||
9231 | if (!perf_tp_filter_match(event, data)) | |
9232 | return 0; | |
9233 | ||
9234 | return 1; | |
9235 | } | |
9236 | ||
85b67bcb AS |
9237 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9238 | struct trace_event_call *call, u64 count, | |
9239 | struct pt_regs *regs, struct hlist_head *head, | |
9240 | struct task_struct *task) | |
9241 | { | |
e87c6bc3 | 9242 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9243 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9244 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9245 | perf_swevent_put_recursion_context(rctx); |
9246 | return; | |
9247 | } | |
9248 | } | |
9249 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9250 | rctx, task); |
85b67bcb AS |
9251 | } |
9252 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9253 | ||
1e1dcd93 | 9254 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9255 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9256 | struct task_struct *task) |
95476b64 FW |
9257 | { |
9258 | struct perf_sample_data data; | |
8fd0fbbe | 9259 | struct perf_event *event; |
1c024eca | 9260 | |
95476b64 | 9261 | struct perf_raw_record raw = { |
7e3f977e DB |
9262 | .frag = { |
9263 | .size = entry_size, | |
9264 | .data = record, | |
9265 | }, | |
95476b64 FW |
9266 | }; |
9267 | ||
1e1dcd93 | 9268 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9269 | data.raw = &raw; |
9270 | ||
1e1dcd93 AS |
9271 | perf_trace_buf_update(record, event_type); |
9272 | ||
8fd0fbbe | 9273 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9274 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9275 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9276 | } |
ecc55f84 | 9277 | |
e6dab5ff AV |
9278 | /* |
9279 | * If we got specified a target task, also iterate its context and | |
9280 | * deliver this event there too. | |
9281 | */ | |
9282 | if (task && task != current) { | |
9283 | struct perf_event_context *ctx; | |
9284 | struct trace_entry *entry = record; | |
9285 | ||
9286 | rcu_read_lock(); | |
9287 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9288 | if (!ctx) | |
9289 | goto unlock; | |
9290 | ||
9291 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9292 | if (event->cpu != smp_processor_id()) |
9293 | continue; | |
e6dab5ff AV |
9294 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9295 | continue; | |
9296 | if (event->attr.config != entry->type) | |
9297 | continue; | |
9298 | if (perf_tp_event_match(event, &data, regs)) | |
9299 | perf_swevent_event(event, count, &data, regs); | |
9300 | } | |
9301 | unlock: | |
9302 | rcu_read_unlock(); | |
9303 | } | |
9304 | ||
ecc55f84 | 9305 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9306 | } |
9307 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9308 | ||
cdd6c482 | 9309 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9310 | { |
1c024eca | 9311 | perf_trace_destroy(event); |
e077df4f PZ |
9312 | } |
9313 | ||
b0a873eb | 9314 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9315 | { |
76e1d904 FW |
9316 | int err; |
9317 | ||
b0a873eb PZ |
9318 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9319 | return -ENOENT; | |
9320 | ||
2481c5fa SE |
9321 | /* |
9322 | * no branch sampling for tracepoint events | |
9323 | */ | |
9324 | if (has_branch_stack(event)) | |
9325 | return -EOPNOTSUPP; | |
9326 | ||
1c024eca PZ |
9327 | err = perf_trace_init(event); |
9328 | if (err) | |
b0a873eb | 9329 | return err; |
e077df4f | 9330 | |
cdd6c482 | 9331 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9332 | |
b0a873eb PZ |
9333 | return 0; |
9334 | } | |
9335 | ||
9336 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9337 | .task_ctx_nr = perf_sw_context, |
9338 | ||
b0a873eb | 9339 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9340 | .add = perf_trace_add, |
9341 | .del = perf_trace_del, | |
9342 | .start = perf_swevent_start, | |
9343 | .stop = perf_swevent_stop, | |
b0a873eb | 9344 | .read = perf_swevent_read, |
b0a873eb PZ |
9345 | }; |
9346 | ||
33ea4b24 | 9347 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9348 | /* |
9349 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9350 | * The flags should match following PMU_FORMAT_ATTR(). | |
9351 | * | |
9352 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9353 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9354 | * |
9355 | * The following values specify a reference counter (or semaphore in the | |
9356 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9357 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9358 | * | |
9359 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9360 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9361 | */ |
9362 | enum perf_probe_config { | |
9363 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9364 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9365 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9366 | }; |
9367 | ||
9368 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9369 | #endif |
e12f03d7 | 9370 | |
a6ca88b2 SL |
9371 | #ifdef CONFIG_KPROBE_EVENTS |
9372 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9373 | &format_attr_retprobe.attr, |
9374 | NULL, | |
9375 | }; | |
9376 | ||
a6ca88b2 | 9377 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9378 | .name = "format", |
a6ca88b2 | 9379 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9380 | }; |
9381 | ||
a6ca88b2 SL |
9382 | static const struct attribute_group *kprobe_attr_groups[] = { |
9383 | &kprobe_format_group, | |
e12f03d7 SL |
9384 | NULL, |
9385 | }; | |
9386 | ||
9387 | static int perf_kprobe_event_init(struct perf_event *event); | |
9388 | static struct pmu perf_kprobe = { | |
9389 | .task_ctx_nr = perf_sw_context, | |
9390 | .event_init = perf_kprobe_event_init, | |
9391 | .add = perf_trace_add, | |
9392 | .del = perf_trace_del, | |
9393 | .start = perf_swevent_start, | |
9394 | .stop = perf_swevent_stop, | |
9395 | .read = perf_swevent_read, | |
a6ca88b2 | 9396 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9397 | }; |
9398 | ||
9399 | static int perf_kprobe_event_init(struct perf_event *event) | |
9400 | { | |
9401 | int err; | |
9402 | bool is_retprobe; | |
9403 | ||
9404 | if (event->attr.type != perf_kprobe.type) | |
9405 | return -ENOENT; | |
32e6e967 SL |
9406 | |
9407 | if (!capable(CAP_SYS_ADMIN)) | |
9408 | return -EACCES; | |
9409 | ||
e12f03d7 SL |
9410 | /* |
9411 | * no branch sampling for probe events | |
9412 | */ | |
9413 | if (has_branch_stack(event)) | |
9414 | return -EOPNOTSUPP; | |
9415 | ||
9416 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9417 | err = perf_kprobe_init(event, is_retprobe); | |
9418 | if (err) | |
9419 | return err; | |
9420 | ||
9421 | event->destroy = perf_kprobe_destroy; | |
9422 | ||
9423 | return 0; | |
9424 | } | |
9425 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9426 | ||
33ea4b24 | 9427 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9428 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9429 | ||
9430 | static struct attribute *uprobe_attrs[] = { | |
9431 | &format_attr_retprobe.attr, | |
9432 | &format_attr_ref_ctr_offset.attr, | |
9433 | NULL, | |
9434 | }; | |
9435 | ||
9436 | static struct attribute_group uprobe_format_group = { | |
9437 | .name = "format", | |
9438 | .attrs = uprobe_attrs, | |
9439 | }; | |
9440 | ||
9441 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9442 | &uprobe_format_group, | |
9443 | NULL, | |
9444 | }; | |
9445 | ||
33ea4b24 SL |
9446 | static int perf_uprobe_event_init(struct perf_event *event); |
9447 | static struct pmu perf_uprobe = { | |
9448 | .task_ctx_nr = perf_sw_context, | |
9449 | .event_init = perf_uprobe_event_init, | |
9450 | .add = perf_trace_add, | |
9451 | .del = perf_trace_del, | |
9452 | .start = perf_swevent_start, | |
9453 | .stop = perf_swevent_stop, | |
9454 | .read = perf_swevent_read, | |
a6ca88b2 | 9455 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9456 | }; |
9457 | ||
9458 | static int perf_uprobe_event_init(struct perf_event *event) | |
9459 | { | |
9460 | int err; | |
a6ca88b2 | 9461 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9462 | bool is_retprobe; |
9463 | ||
9464 | if (event->attr.type != perf_uprobe.type) | |
9465 | return -ENOENT; | |
32e6e967 SL |
9466 | |
9467 | if (!capable(CAP_SYS_ADMIN)) | |
9468 | return -EACCES; | |
9469 | ||
33ea4b24 SL |
9470 | /* |
9471 | * no branch sampling for probe events | |
9472 | */ | |
9473 | if (has_branch_stack(event)) | |
9474 | return -EOPNOTSUPP; | |
9475 | ||
9476 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9477 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9478 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9479 | if (err) |
9480 | return err; | |
9481 | ||
9482 | event->destroy = perf_uprobe_destroy; | |
9483 | ||
9484 | return 0; | |
9485 | } | |
9486 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9487 | ||
b0a873eb PZ |
9488 | static inline void perf_tp_register(void) |
9489 | { | |
2e80a82a | 9490 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9491 | #ifdef CONFIG_KPROBE_EVENTS |
9492 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9493 | #endif | |
33ea4b24 SL |
9494 | #ifdef CONFIG_UPROBE_EVENTS |
9495 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9496 | #endif | |
e077df4f | 9497 | } |
6fb2915d | 9498 | |
6fb2915d LZ |
9499 | static void perf_event_free_filter(struct perf_event *event) |
9500 | { | |
9501 | ftrace_profile_free_filter(event); | |
9502 | } | |
9503 | ||
aa6a5f3c AS |
9504 | #ifdef CONFIG_BPF_SYSCALL |
9505 | static void bpf_overflow_handler(struct perf_event *event, | |
9506 | struct perf_sample_data *data, | |
9507 | struct pt_regs *regs) | |
9508 | { | |
9509 | struct bpf_perf_event_data_kern ctx = { | |
9510 | .data = data, | |
7d9285e8 | 9511 | .event = event, |
aa6a5f3c AS |
9512 | }; |
9513 | int ret = 0; | |
9514 | ||
c895f6f7 | 9515 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9516 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) |
9517 | goto out; | |
9518 | rcu_read_lock(); | |
88575199 | 9519 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9520 | rcu_read_unlock(); |
9521 | out: | |
9522 | __this_cpu_dec(bpf_prog_active); | |
aa6a5f3c AS |
9523 | if (!ret) |
9524 | return; | |
9525 | ||
9526 | event->orig_overflow_handler(event, data, regs); | |
9527 | } | |
9528 | ||
9529 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9530 | { | |
9531 | struct bpf_prog *prog; | |
9532 | ||
9533 | if (event->overflow_handler_context) | |
9534 | /* hw breakpoint or kernel counter */ | |
9535 | return -EINVAL; | |
9536 | ||
9537 | if (event->prog) | |
9538 | return -EEXIST; | |
9539 | ||
9540 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9541 | if (IS_ERR(prog)) | |
9542 | return PTR_ERR(prog); | |
9543 | ||
9544 | event->prog = prog; | |
9545 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9546 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9547 | return 0; | |
9548 | } | |
9549 | ||
9550 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9551 | { | |
9552 | struct bpf_prog *prog = event->prog; | |
9553 | ||
9554 | if (!prog) | |
9555 | return; | |
9556 | ||
9557 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9558 | event->prog = NULL; | |
9559 | bpf_prog_put(prog); | |
9560 | } | |
9561 | #else | |
9562 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9563 | { | |
9564 | return -EOPNOTSUPP; | |
9565 | } | |
9566 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9567 | { | |
9568 | } | |
9569 | #endif | |
9570 | ||
e12f03d7 SL |
9571 | /* |
9572 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9573 | * with perf_event_open() | |
9574 | */ | |
9575 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9576 | { | |
9577 | if (event->pmu == &perf_tracepoint) | |
9578 | return true; | |
9579 | #ifdef CONFIG_KPROBE_EVENTS | |
9580 | if (event->pmu == &perf_kprobe) | |
9581 | return true; | |
33ea4b24 SL |
9582 | #endif |
9583 | #ifdef CONFIG_UPROBE_EVENTS | |
9584 | if (event->pmu == &perf_uprobe) | |
9585 | return true; | |
e12f03d7 SL |
9586 | #endif |
9587 | return false; | |
9588 | } | |
9589 | ||
2541517c AS |
9590 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9591 | { | |
cf5f5cea | 9592 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9593 | struct bpf_prog *prog; |
e87c6bc3 | 9594 | int ret; |
2541517c | 9595 | |
e12f03d7 | 9596 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9597 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9598 | |
98b5c2c6 AS |
9599 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9600 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9601 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9602 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9603 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9604 | return -EINVAL; |
9605 | ||
9606 | prog = bpf_prog_get(prog_fd); | |
9607 | if (IS_ERR(prog)) | |
9608 | return PTR_ERR(prog); | |
9609 | ||
98b5c2c6 | 9610 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9611 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9612 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9613 | /* valid fd, but invalid bpf program type */ |
9614 | bpf_prog_put(prog); | |
9615 | return -EINVAL; | |
9616 | } | |
9617 | ||
9802d865 JB |
9618 | /* Kprobe override only works for kprobes, not uprobes. */ |
9619 | if (prog->kprobe_override && | |
9620 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9621 | bpf_prog_put(prog); | |
9622 | return -EINVAL; | |
9623 | } | |
9624 | ||
cf5f5cea | 9625 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9626 | int off = trace_event_get_offsets(event->tp_event); |
9627 | ||
9628 | if (prog->aux->max_ctx_offset > off) { | |
9629 | bpf_prog_put(prog); | |
9630 | return -EACCES; | |
9631 | } | |
9632 | } | |
2541517c | 9633 | |
e87c6bc3 YS |
9634 | ret = perf_event_attach_bpf_prog(event, prog); |
9635 | if (ret) | |
9636 | bpf_prog_put(prog); | |
9637 | return ret; | |
2541517c AS |
9638 | } |
9639 | ||
9640 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9641 | { | |
e12f03d7 | 9642 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9643 | perf_event_free_bpf_handler(event); |
2541517c | 9644 | return; |
2541517c | 9645 | } |
e87c6bc3 | 9646 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9647 | } |
9648 | ||
e077df4f | 9649 | #else |
6fb2915d | 9650 | |
b0a873eb | 9651 | static inline void perf_tp_register(void) |
e077df4f | 9652 | { |
e077df4f | 9653 | } |
6fb2915d | 9654 | |
6fb2915d LZ |
9655 | static void perf_event_free_filter(struct perf_event *event) |
9656 | { | |
9657 | } | |
9658 | ||
2541517c AS |
9659 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9660 | { | |
9661 | return -ENOENT; | |
9662 | } | |
9663 | ||
9664 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9665 | { | |
9666 | } | |
07b139c8 | 9667 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9668 | |
24f1e32c | 9669 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9670 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9671 | { |
f5ffe02e FW |
9672 | struct perf_sample_data sample; |
9673 | struct pt_regs *regs = data; | |
9674 | ||
fd0d000b | 9675 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9676 | |
a4eaf7f1 | 9677 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9678 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9679 | } |
9680 | #endif | |
9681 | ||
375637bc AS |
9682 | /* |
9683 | * Allocate a new address filter | |
9684 | */ | |
9685 | static struct perf_addr_filter * | |
9686 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9687 | { | |
9688 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9689 | struct perf_addr_filter *filter; | |
9690 | ||
9691 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9692 | if (!filter) | |
9693 | return NULL; | |
9694 | ||
9695 | INIT_LIST_HEAD(&filter->entry); | |
9696 | list_add_tail(&filter->entry, filters); | |
9697 | ||
9698 | return filter; | |
9699 | } | |
9700 | ||
9701 | static void free_filters_list(struct list_head *filters) | |
9702 | { | |
9703 | struct perf_addr_filter *filter, *iter; | |
9704 | ||
9705 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9706 | path_put(&filter->path); |
375637bc AS |
9707 | list_del(&filter->entry); |
9708 | kfree(filter); | |
9709 | } | |
9710 | } | |
9711 | ||
9712 | /* | |
9713 | * Free existing address filters and optionally install new ones | |
9714 | */ | |
9715 | static void perf_addr_filters_splice(struct perf_event *event, | |
9716 | struct list_head *head) | |
9717 | { | |
9718 | unsigned long flags; | |
9719 | LIST_HEAD(list); | |
9720 | ||
9721 | if (!has_addr_filter(event)) | |
9722 | return; | |
9723 | ||
9724 | /* don't bother with children, they don't have their own filters */ | |
9725 | if (event->parent) | |
9726 | return; | |
9727 | ||
9728 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9729 | ||
9730 | list_splice_init(&event->addr_filters.list, &list); | |
9731 | if (head) | |
9732 | list_splice(head, &event->addr_filters.list); | |
9733 | ||
9734 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9735 | ||
9736 | free_filters_list(&list); | |
9737 | } | |
9738 | ||
9739 | /* | |
9740 | * Scan through mm's vmas and see if one of them matches the | |
9741 | * @filter; if so, adjust filter's address range. | |
9742 | * Called with mm::mmap_sem down for reading. | |
9743 | */ | |
c60f83b8 AS |
9744 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9745 | struct mm_struct *mm, | |
9746 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9747 | { |
9748 | struct vm_area_struct *vma; | |
9749 | ||
9750 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9751 | if (!vma->vm_file) |
375637bc AS |
9752 | continue; |
9753 | ||
c60f83b8 AS |
9754 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9755 | return; | |
375637bc | 9756 | } |
375637bc AS |
9757 | } |
9758 | ||
9759 | /* | |
9760 | * Update event's address range filters based on the | |
9761 | * task's existing mappings, if any. | |
9762 | */ | |
9763 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9764 | { | |
9765 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9766 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9767 | struct perf_addr_filter *filter; | |
9768 | struct mm_struct *mm = NULL; | |
9769 | unsigned int count = 0; | |
9770 | unsigned long flags; | |
9771 | ||
9772 | /* | |
9773 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9774 | * will stop on the parent's child_mutex that our caller is also holding | |
9775 | */ | |
9776 | if (task == TASK_TOMBSTONE) | |
9777 | return; | |
9778 | ||
52a44f83 AS |
9779 | if (ifh->nr_file_filters) { |
9780 | mm = get_task_mm(event->ctx->task); | |
9781 | if (!mm) | |
9782 | goto restart; | |
375637bc | 9783 | |
52a44f83 AS |
9784 | down_read(&mm->mmap_sem); |
9785 | } | |
375637bc AS |
9786 | |
9787 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9788 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9789 | if (filter->path.dentry) { |
9790 | /* | |
9791 | * Adjust base offset if the filter is associated to a | |
9792 | * binary that needs to be mapped: | |
9793 | */ | |
9794 | event->addr_filter_ranges[count].start = 0; | |
9795 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9796 | |
c60f83b8 | 9797 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9798 | } else { |
9799 | event->addr_filter_ranges[count].start = filter->offset; | |
9800 | event->addr_filter_ranges[count].size = filter->size; | |
9801 | } | |
375637bc AS |
9802 | |
9803 | count++; | |
9804 | } | |
9805 | ||
9806 | event->addr_filters_gen++; | |
9807 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9808 | ||
52a44f83 AS |
9809 | if (ifh->nr_file_filters) { |
9810 | up_read(&mm->mmap_sem); | |
375637bc | 9811 | |
52a44f83 AS |
9812 | mmput(mm); |
9813 | } | |
375637bc AS |
9814 | |
9815 | restart: | |
767ae086 | 9816 | perf_event_stop(event, 1); |
375637bc AS |
9817 | } |
9818 | ||
9819 | /* | |
9820 | * Address range filtering: limiting the data to certain | |
9821 | * instruction address ranges. Filters are ioctl()ed to us from | |
9822 | * userspace as ascii strings. | |
9823 | * | |
9824 | * Filter string format: | |
9825 | * | |
9826 | * ACTION RANGE_SPEC | |
9827 | * where ACTION is one of the | |
9828 | * * "filter": limit the trace to this region | |
9829 | * * "start": start tracing from this address | |
9830 | * * "stop": stop tracing at this address/region; | |
9831 | * RANGE_SPEC is | |
9832 | * * for kernel addresses: <start address>[/<size>] | |
9833 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9834 | * | |
6ed70cf3 AS |
9835 | * if <size> is not specified or is zero, the range is treated as a single |
9836 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9837 | */ |
9838 | enum { | |
e96271f3 | 9839 | IF_ACT_NONE = -1, |
375637bc AS |
9840 | IF_ACT_FILTER, |
9841 | IF_ACT_START, | |
9842 | IF_ACT_STOP, | |
9843 | IF_SRC_FILE, | |
9844 | IF_SRC_KERNEL, | |
9845 | IF_SRC_FILEADDR, | |
9846 | IF_SRC_KERNELADDR, | |
9847 | }; | |
9848 | ||
9849 | enum { | |
9850 | IF_STATE_ACTION = 0, | |
9851 | IF_STATE_SOURCE, | |
9852 | IF_STATE_END, | |
9853 | }; | |
9854 | ||
9855 | static const match_table_t if_tokens = { | |
9856 | { IF_ACT_FILTER, "filter" }, | |
9857 | { IF_ACT_START, "start" }, | |
9858 | { IF_ACT_STOP, "stop" }, | |
9859 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9860 | { IF_SRC_KERNEL, "%u/%u" }, | |
9861 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9862 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9863 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9864 | }; |
9865 | ||
9866 | /* | |
9867 | * Address filter string parser | |
9868 | */ | |
9869 | static int | |
9870 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9871 | struct list_head *filters) | |
9872 | { | |
9873 | struct perf_addr_filter *filter = NULL; | |
9874 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9875 | substring_t args[MAX_OPT_ARGS]; |
9876 | int state = IF_STATE_ACTION, token; | |
9877 | unsigned int kernel = 0; | |
9878 | int ret = -EINVAL; | |
9879 | ||
9880 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9881 | if (!fstr) | |
9882 | return -ENOMEM; | |
9883 | ||
9884 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9885 | static const enum perf_addr_filter_action_t actions[] = { |
9886 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9887 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9888 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9889 | }; | |
375637bc AS |
9890 | ret = -EINVAL; |
9891 | ||
9892 | if (!*start) | |
9893 | continue; | |
9894 | ||
9895 | /* filter definition begins */ | |
9896 | if (state == IF_STATE_ACTION) { | |
9897 | filter = perf_addr_filter_new(event, filters); | |
9898 | if (!filter) | |
9899 | goto fail; | |
9900 | } | |
9901 | ||
9902 | token = match_token(start, if_tokens, args); | |
9903 | switch (token) { | |
9904 | case IF_ACT_FILTER: | |
9905 | case IF_ACT_START: | |
375637bc AS |
9906 | case IF_ACT_STOP: |
9907 | if (state != IF_STATE_ACTION) | |
9908 | goto fail; | |
9909 | ||
6ed70cf3 | 9910 | filter->action = actions[token]; |
375637bc AS |
9911 | state = IF_STATE_SOURCE; |
9912 | break; | |
9913 | ||
9914 | case IF_SRC_KERNELADDR: | |
9915 | case IF_SRC_KERNEL: | |
9916 | kernel = 1; | |
10c3405f | 9917 | /* fall through */ |
375637bc AS |
9918 | |
9919 | case IF_SRC_FILEADDR: | |
9920 | case IF_SRC_FILE: | |
9921 | if (state != IF_STATE_SOURCE) | |
9922 | goto fail; | |
9923 | ||
375637bc AS |
9924 | *args[0].to = 0; |
9925 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9926 | if (ret) | |
9927 | goto fail; | |
9928 | ||
6ed70cf3 | 9929 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9930 | *args[1].to = 0; |
9931 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9932 | if (ret) | |
9933 | goto fail; | |
9934 | } | |
9935 | ||
4059ffd0 | 9936 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9937 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9938 | |
9939 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9940 | if (!filename) { |
9941 | ret = -ENOMEM; | |
9942 | goto fail; | |
9943 | } | |
9944 | } | |
9945 | ||
9946 | state = IF_STATE_END; | |
9947 | break; | |
9948 | ||
9949 | default: | |
9950 | goto fail; | |
9951 | } | |
9952 | ||
9953 | /* | |
9954 | * Filter definition is fully parsed, validate and install it. | |
9955 | * Make sure that it doesn't contradict itself or the event's | |
9956 | * attribute. | |
9957 | */ | |
9958 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9959 | ret = -EINVAL; |
375637bc AS |
9960 | if (kernel && event->attr.exclude_kernel) |
9961 | goto fail; | |
9962 | ||
6ed70cf3 AS |
9963 | /* |
9964 | * ACTION "filter" must have a non-zero length region | |
9965 | * specified. | |
9966 | */ | |
9967 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9968 | !filter->size) | |
9969 | goto fail; | |
9970 | ||
375637bc AS |
9971 | if (!kernel) { |
9972 | if (!filename) | |
9973 | goto fail; | |
9974 | ||
6ce77bfd AS |
9975 | /* |
9976 | * For now, we only support file-based filters | |
9977 | * in per-task events; doing so for CPU-wide | |
9978 | * events requires additional context switching | |
9979 | * trickery, since same object code will be | |
9980 | * mapped at different virtual addresses in | |
9981 | * different processes. | |
9982 | */ | |
9983 | ret = -EOPNOTSUPP; | |
9984 | if (!event->ctx->task) | |
9985 | goto fail_free_name; | |
9986 | ||
375637bc | 9987 | /* look up the path and grab its inode */ |
9511bce9 SL |
9988 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9989 | &filter->path); | |
375637bc AS |
9990 | if (ret) |
9991 | goto fail_free_name; | |
9992 | ||
375637bc AS |
9993 | kfree(filename); |
9994 | filename = NULL; | |
9995 | ||
9996 | ret = -EINVAL; | |
9511bce9 SL |
9997 | if (!filter->path.dentry || |
9998 | !S_ISREG(d_inode(filter->path.dentry) | |
9999 | ->i_mode)) | |
375637bc | 10000 | goto fail; |
6ce77bfd AS |
10001 | |
10002 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
10003 | } |
10004 | ||
10005 | /* ready to consume more filters */ | |
10006 | state = IF_STATE_ACTION; | |
10007 | filter = NULL; | |
10008 | } | |
10009 | } | |
10010 | ||
10011 | if (state != IF_STATE_ACTION) | |
10012 | goto fail; | |
10013 | ||
10014 | kfree(orig); | |
10015 | ||
10016 | return 0; | |
10017 | ||
10018 | fail_free_name: | |
10019 | kfree(filename); | |
10020 | fail: | |
10021 | free_filters_list(filters); | |
10022 | kfree(orig); | |
10023 | ||
10024 | return ret; | |
10025 | } | |
10026 | ||
10027 | static int | |
10028 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
10029 | { | |
10030 | LIST_HEAD(filters); | |
10031 | int ret; | |
10032 | ||
10033 | /* | |
10034 | * Since this is called in perf_ioctl() path, we're already holding | |
10035 | * ctx::mutex. | |
10036 | */ | |
10037 | lockdep_assert_held(&event->ctx->mutex); | |
10038 | ||
10039 | if (WARN_ON_ONCE(event->parent)) | |
10040 | return -EINVAL; | |
10041 | ||
375637bc AS |
10042 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
10043 | if (ret) | |
6ce77bfd | 10044 | goto fail_clear_files; |
375637bc AS |
10045 | |
10046 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
10047 | if (ret) |
10048 | goto fail_free_filters; | |
375637bc AS |
10049 | |
10050 | /* remove existing filters, if any */ | |
10051 | perf_addr_filters_splice(event, &filters); | |
10052 | ||
10053 | /* install new filters */ | |
10054 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
10055 | ||
6ce77bfd AS |
10056 | return ret; |
10057 | ||
10058 | fail_free_filters: | |
10059 | free_filters_list(&filters); | |
10060 | ||
10061 | fail_clear_files: | |
10062 | event->addr_filters.nr_file_filters = 0; | |
10063 | ||
375637bc AS |
10064 | return ret; |
10065 | } | |
10066 | ||
c796bbbe AS |
10067 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
10068 | { | |
c796bbbe | 10069 | int ret = -EINVAL; |
e12f03d7 | 10070 | char *filter_str; |
c796bbbe AS |
10071 | |
10072 | filter_str = strndup_user(arg, PAGE_SIZE); | |
10073 | if (IS_ERR(filter_str)) | |
10074 | return PTR_ERR(filter_str); | |
10075 | ||
e12f03d7 SL |
10076 | #ifdef CONFIG_EVENT_TRACING |
10077 | if (perf_event_is_tracing(event)) { | |
10078 | struct perf_event_context *ctx = event->ctx; | |
10079 | ||
10080 | /* | |
10081 | * Beware, here be dragons!! | |
10082 | * | |
10083 | * the tracepoint muck will deadlock against ctx->mutex, but | |
10084 | * the tracepoint stuff does not actually need it. So | |
10085 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
10086 | * already have a reference on ctx. | |
10087 | * | |
10088 | * This can result in event getting moved to a different ctx, | |
10089 | * but that does not affect the tracepoint state. | |
10090 | */ | |
10091 | mutex_unlock(&ctx->mutex); | |
10092 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
10093 | mutex_lock(&ctx->mutex); | |
10094 | } else | |
10095 | #endif | |
10096 | if (has_addr_filter(event)) | |
375637bc | 10097 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
10098 | |
10099 | kfree(filter_str); | |
10100 | return ret; | |
10101 | } | |
10102 | ||
b0a873eb PZ |
10103 | /* |
10104 | * hrtimer based swevent callback | |
10105 | */ | |
f29ac756 | 10106 | |
b0a873eb | 10107 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 10108 | { |
b0a873eb PZ |
10109 | enum hrtimer_restart ret = HRTIMER_RESTART; |
10110 | struct perf_sample_data data; | |
10111 | struct pt_regs *regs; | |
10112 | struct perf_event *event; | |
10113 | u64 period; | |
f29ac756 | 10114 | |
b0a873eb | 10115 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
10116 | |
10117 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
10118 | return HRTIMER_NORESTART; | |
10119 | ||
b0a873eb | 10120 | event->pmu->read(event); |
f344011c | 10121 | |
fd0d000b | 10122 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
10123 | regs = get_irq_regs(); |
10124 | ||
10125 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 10126 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 10127 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
10128 | ret = HRTIMER_NORESTART; |
10129 | } | |
24f1e32c | 10130 | |
b0a873eb PZ |
10131 | period = max_t(u64, 10000, event->hw.sample_period); |
10132 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 10133 | |
b0a873eb | 10134 | return ret; |
f29ac756 PZ |
10135 | } |
10136 | ||
b0a873eb | 10137 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 10138 | { |
b0a873eb | 10139 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
10140 | s64 period; |
10141 | ||
10142 | if (!is_sampling_event(event)) | |
10143 | return; | |
f5ffe02e | 10144 | |
5d508e82 FBH |
10145 | period = local64_read(&hwc->period_left); |
10146 | if (period) { | |
10147 | if (period < 0) | |
10148 | period = 10000; | |
fa407f35 | 10149 | |
5d508e82 FBH |
10150 | local64_set(&hwc->period_left, 0); |
10151 | } else { | |
10152 | period = max_t(u64, 10000, hwc->sample_period); | |
10153 | } | |
3497d206 | 10154 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10155 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10156 | } |
b0a873eb PZ |
10157 | |
10158 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10159 | { |
b0a873eb PZ |
10160 | struct hw_perf_event *hwc = &event->hw; |
10161 | ||
6c7e550f | 10162 | if (is_sampling_event(event)) { |
b0a873eb | 10163 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10164 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10165 | |
10166 | hrtimer_cancel(&hwc->hrtimer); | |
10167 | } | |
24f1e32c FW |
10168 | } |
10169 | ||
ba3dd36c PZ |
10170 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10171 | { | |
10172 | struct hw_perf_event *hwc = &event->hw; | |
10173 | ||
10174 | if (!is_sampling_event(event)) | |
10175 | return; | |
10176 | ||
30f9028b | 10177 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10178 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10179 | ||
10180 | /* | |
10181 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10182 | * mapping and avoid the whole period adjust feedback stuff. | |
10183 | */ | |
10184 | if (event->attr.freq) { | |
10185 | long freq = event->attr.sample_freq; | |
10186 | ||
10187 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10188 | hwc->sample_period = event->attr.sample_period; | |
10189 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10190 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10191 | event->attr.freq = 0; |
10192 | } | |
10193 | } | |
10194 | ||
b0a873eb PZ |
10195 | /* |
10196 | * Software event: cpu wall time clock | |
10197 | */ | |
10198 | ||
10199 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10200 | { |
b0a873eb PZ |
10201 | s64 prev; |
10202 | u64 now; | |
10203 | ||
a4eaf7f1 | 10204 | now = local_clock(); |
b0a873eb PZ |
10205 | prev = local64_xchg(&event->hw.prev_count, now); |
10206 | local64_add(now - prev, &event->count); | |
24f1e32c | 10207 | } |
24f1e32c | 10208 | |
a4eaf7f1 | 10209 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10210 | { |
a4eaf7f1 | 10211 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10212 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10213 | } |
10214 | ||
a4eaf7f1 | 10215 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10216 | { |
b0a873eb PZ |
10217 | perf_swevent_cancel_hrtimer(event); |
10218 | cpu_clock_event_update(event); | |
10219 | } | |
f29ac756 | 10220 | |
a4eaf7f1 PZ |
10221 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10222 | { | |
10223 | if (flags & PERF_EF_START) | |
10224 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10225 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10226 | |
10227 | return 0; | |
10228 | } | |
10229 | ||
10230 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10231 | { | |
10232 | cpu_clock_event_stop(event, flags); | |
10233 | } | |
10234 | ||
b0a873eb PZ |
10235 | static void cpu_clock_event_read(struct perf_event *event) |
10236 | { | |
10237 | cpu_clock_event_update(event); | |
10238 | } | |
f344011c | 10239 | |
b0a873eb PZ |
10240 | static int cpu_clock_event_init(struct perf_event *event) |
10241 | { | |
10242 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10243 | return -ENOENT; | |
10244 | ||
10245 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10246 | return -ENOENT; | |
10247 | ||
2481c5fa SE |
10248 | /* |
10249 | * no branch sampling for software events | |
10250 | */ | |
10251 | if (has_branch_stack(event)) | |
10252 | return -EOPNOTSUPP; | |
10253 | ||
ba3dd36c PZ |
10254 | perf_swevent_init_hrtimer(event); |
10255 | ||
b0a873eb | 10256 | return 0; |
f29ac756 PZ |
10257 | } |
10258 | ||
b0a873eb | 10259 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10260 | .task_ctx_nr = perf_sw_context, |
10261 | ||
34f43927 PZ |
10262 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10263 | ||
b0a873eb | 10264 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10265 | .add = cpu_clock_event_add, |
10266 | .del = cpu_clock_event_del, | |
10267 | .start = cpu_clock_event_start, | |
10268 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10269 | .read = cpu_clock_event_read, |
10270 | }; | |
10271 | ||
10272 | /* | |
10273 | * Software event: task time clock | |
10274 | */ | |
10275 | ||
10276 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10277 | { |
b0a873eb PZ |
10278 | u64 prev; |
10279 | s64 delta; | |
5c92d124 | 10280 | |
b0a873eb PZ |
10281 | prev = local64_xchg(&event->hw.prev_count, now); |
10282 | delta = now - prev; | |
10283 | local64_add(delta, &event->count); | |
10284 | } | |
5c92d124 | 10285 | |
a4eaf7f1 | 10286 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10287 | { |
a4eaf7f1 | 10288 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10289 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10290 | } |
10291 | ||
a4eaf7f1 | 10292 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10293 | { |
10294 | perf_swevent_cancel_hrtimer(event); | |
10295 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10296 | } |
10297 | ||
10298 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10299 | { | |
10300 | if (flags & PERF_EF_START) | |
10301 | task_clock_event_start(event, flags); | |
6a694a60 | 10302 | perf_event_update_userpage(event); |
b0a873eb | 10303 | |
a4eaf7f1 PZ |
10304 | return 0; |
10305 | } | |
10306 | ||
10307 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10308 | { | |
10309 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10310 | } |
10311 | ||
10312 | static void task_clock_event_read(struct perf_event *event) | |
10313 | { | |
768a06e2 PZ |
10314 | u64 now = perf_clock(); |
10315 | u64 delta = now - event->ctx->timestamp; | |
10316 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10317 | |
10318 | task_clock_event_update(event, time); | |
10319 | } | |
10320 | ||
10321 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10322 | { |
b0a873eb PZ |
10323 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10324 | return -ENOENT; | |
10325 | ||
10326 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10327 | return -ENOENT; | |
10328 | ||
2481c5fa SE |
10329 | /* |
10330 | * no branch sampling for software events | |
10331 | */ | |
10332 | if (has_branch_stack(event)) | |
10333 | return -EOPNOTSUPP; | |
10334 | ||
ba3dd36c PZ |
10335 | perf_swevent_init_hrtimer(event); |
10336 | ||
b0a873eb | 10337 | return 0; |
6fb2915d LZ |
10338 | } |
10339 | ||
b0a873eb | 10340 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10341 | .task_ctx_nr = perf_sw_context, |
10342 | ||
34f43927 PZ |
10343 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10344 | ||
b0a873eb | 10345 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10346 | .add = task_clock_event_add, |
10347 | .del = task_clock_event_del, | |
10348 | .start = task_clock_event_start, | |
10349 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10350 | .read = task_clock_event_read, |
10351 | }; | |
6fb2915d | 10352 | |
ad5133b7 | 10353 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10354 | { |
e077df4f | 10355 | } |
6fb2915d | 10356 | |
fbbe0701 SB |
10357 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10358 | { | |
10359 | } | |
10360 | ||
ad5133b7 | 10361 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10362 | { |
ad5133b7 | 10363 | return 0; |
6fb2915d LZ |
10364 | } |
10365 | ||
81ec3f3c JO |
10366 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10367 | { | |
10368 | return 0; | |
10369 | } | |
10370 | ||
18ab2cd3 | 10371 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10372 | |
10373 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10374 | { |
fbbe0701 SB |
10375 | __this_cpu_write(nop_txn_flags, flags); |
10376 | ||
10377 | if (flags & ~PERF_PMU_TXN_ADD) | |
10378 | return; | |
10379 | ||
ad5133b7 | 10380 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10381 | } |
10382 | ||
ad5133b7 PZ |
10383 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10384 | { | |
fbbe0701 SB |
10385 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10386 | ||
10387 | __this_cpu_write(nop_txn_flags, 0); | |
10388 | ||
10389 | if (flags & ~PERF_PMU_TXN_ADD) | |
10390 | return 0; | |
10391 | ||
ad5133b7 PZ |
10392 | perf_pmu_enable(pmu); |
10393 | return 0; | |
10394 | } | |
e077df4f | 10395 | |
ad5133b7 | 10396 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10397 | { |
fbbe0701 SB |
10398 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10399 | ||
10400 | __this_cpu_write(nop_txn_flags, 0); | |
10401 | ||
10402 | if (flags & ~PERF_PMU_TXN_ADD) | |
10403 | return; | |
10404 | ||
ad5133b7 | 10405 | perf_pmu_enable(pmu); |
24f1e32c FW |
10406 | } |
10407 | ||
35edc2a5 PZ |
10408 | static int perf_event_idx_default(struct perf_event *event) |
10409 | { | |
c719f560 | 10410 | return 0; |
35edc2a5 PZ |
10411 | } |
10412 | ||
8dc85d54 PZ |
10413 | /* |
10414 | * Ensures all contexts with the same task_ctx_nr have the same | |
10415 | * pmu_cpu_context too. | |
10416 | */ | |
9e317041 | 10417 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10418 | { |
8dc85d54 | 10419 | struct pmu *pmu; |
b326e956 | 10420 | |
8dc85d54 PZ |
10421 | if (ctxn < 0) |
10422 | return NULL; | |
24f1e32c | 10423 | |
8dc85d54 PZ |
10424 | list_for_each_entry(pmu, &pmus, entry) { |
10425 | if (pmu->task_ctx_nr == ctxn) | |
10426 | return pmu->pmu_cpu_context; | |
10427 | } | |
24f1e32c | 10428 | |
8dc85d54 | 10429 | return NULL; |
24f1e32c FW |
10430 | } |
10431 | ||
51676957 PZ |
10432 | static void free_pmu_context(struct pmu *pmu) |
10433 | { | |
df0062b2 WD |
10434 | /* |
10435 | * Static contexts such as perf_sw_context have a global lifetime | |
10436 | * and may be shared between different PMUs. Avoid freeing them | |
10437 | * when a single PMU is going away. | |
10438 | */ | |
10439 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10440 | return; | |
10441 | ||
51676957 | 10442 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10443 | } |
6e855cd4 AS |
10444 | |
10445 | /* | |
10446 | * Let userspace know that this PMU supports address range filtering: | |
10447 | */ | |
10448 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10449 | struct device_attribute *attr, | |
10450 | char *page) | |
10451 | { | |
10452 | struct pmu *pmu = dev_get_drvdata(dev); | |
10453 | ||
10454 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10455 | } | |
10456 | DEVICE_ATTR_RO(nr_addr_filters); | |
10457 | ||
2e80a82a | 10458 | static struct idr pmu_idr; |
d6d020e9 | 10459 | |
abe43400 PZ |
10460 | static ssize_t |
10461 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10462 | { | |
10463 | struct pmu *pmu = dev_get_drvdata(dev); | |
10464 | ||
10465 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10466 | } | |
90826ca7 | 10467 | static DEVICE_ATTR_RO(type); |
abe43400 | 10468 | |
62b85639 SE |
10469 | static ssize_t |
10470 | perf_event_mux_interval_ms_show(struct device *dev, | |
10471 | struct device_attribute *attr, | |
10472 | char *page) | |
10473 | { | |
10474 | struct pmu *pmu = dev_get_drvdata(dev); | |
10475 | ||
10476 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10477 | } | |
10478 | ||
272325c4 PZ |
10479 | static DEFINE_MUTEX(mux_interval_mutex); |
10480 | ||
62b85639 SE |
10481 | static ssize_t |
10482 | perf_event_mux_interval_ms_store(struct device *dev, | |
10483 | struct device_attribute *attr, | |
10484 | const char *buf, size_t count) | |
10485 | { | |
10486 | struct pmu *pmu = dev_get_drvdata(dev); | |
10487 | int timer, cpu, ret; | |
10488 | ||
10489 | ret = kstrtoint(buf, 0, &timer); | |
10490 | if (ret) | |
10491 | return ret; | |
10492 | ||
10493 | if (timer < 1) | |
10494 | return -EINVAL; | |
10495 | ||
10496 | /* same value, noting to do */ | |
10497 | if (timer == pmu->hrtimer_interval_ms) | |
10498 | return count; | |
10499 | ||
272325c4 | 10500 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10501 | pmu->hrtimer_interval_ms = timer; |
10502 | ||
10503 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10504 | cpus_read_lock(); |
272325c4 | 10505 | for_each_online_cpu(cpu) { |
62b85639 SE |
10506 | struct perf_cpu_context *cpuctx; |
10507 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10508 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10509 | ||
272325c4 PZ |
10510 | cpu_function_call(cpu, |
10511 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10512 | } |
a63fbed7 | 10513 | cpus_read_unlock(); |
272325c4 | 10514 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10515 | |
10516 | return count; | |
10517 | } | |
90826ca7 | 10518 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10519 | |
90826ca7 GKH |
10520 | static struct attribute *pmu_dev_attrs[] = { |
10521 | &dev_attr_type.attr, | |
10522 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10523 | NULL, | |
abe43400 | 10524 | }; |
90826ca7 | 10525 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10526 | |
10527 | static int pmu_bus_running; | |
10528 | static struct bus_type pmu_bus = { | |
10529 | .name = "event_source", | |
90826ca7 | 10530 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10531 | }; |
10532 | ||
10533 | static void pmu_dev_release(struct device *dev) | |
10534 | { | |
10535 | kfree(dev); | |
10536 | } | |
10537 | ||
10538 | static int pmu_dev_alloc(struct pmu *pmu) | |
10539 | { | |
10540 | int ret = -ENOMEM; | |
10541 | ||
10542 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10543 | if (!pmu->dev) | |
10544 | goto out; | |
10545 | ||
0c9d42ed | 10546 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10547 | device_initialize(pmu->dev); |
10548 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10549 | if (ret) | |
10550 | goto free_dev; | |
10551 | ||
10552 | dev_set_drvdata(pmu->dev, pmu); | |
10553 | pmu->dev->bus = &pmu_bus; | |
10554 | pmu->dev->release = pmu_dev_release; | |
10555 | ret = device_add(pmu->dev); | |
10556 | if (ret) | |
10557 | goto free_dev; | |
10558 | ||
6e855cd4 AS |
10559 | /* For PMUs with address filters, throw in an extra attribute: */ |
10560 | if (pmu->nr_addr_filters) | |
10561 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10562 | ||
10563 | if (ret) | |
10564 | goto del_dev; | |
10565 | ||
f3a3a825 JO |
10566 | if (pmu->attr_update) |
10567 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10568 | ||
10569 | if (ret) | |
10570 | goto del_dev; | |
10571 | ||
abe43400 PZ |
10572 | out: |
10573 | return ret; | |
10574 | ||
6e855cd4 AS |
10575 | del_dev: |
10576 | device_del(pmu->dev); | |
10577 | ||
abe43400 PZ |
10578 | free_dev: |
10579 | put_device(pmu->dev); | |
10580 | goto out; | |
10581 | } | |
10582 | ||
547e9fd7 | 10583 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10584 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10585 | |
03d8e80b | 10586 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10587 | { |
66d258c5 | 10588 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10589 | |
b0a873eb | 10590 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10591 | ret = -ENOMEM; |
10592 | pmu->pmu_disable_count = alloc_percpu(int); | |
10593 | if (!pmu->pmu_disable_count) | |
10594 | goto unlock; | |
f29ac756 | 10595 | |
2e80a82a PZ |
10596 | pmu->type = -1; |
10597 | if (!name) | |
10598 | goto skip_type; | |
10599 | pmu->name = name; | |
10600 | ||
66d258c5 PZ |
10601 | if (type != PERF_TYPE_SOFTWARE) { |
10602 | if (type >= 0) | |
10603 | max = type; | |
10604 | ||
10605 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10606 | if (ret < 0) | |
2e80a82a | 10607 | goto free_pdc; |
66d258c5 PZ |
10608 | |
10609 | WARN_ON(type >= 0 && ret != type); | |
10610 | ||
10611 | type = ret; | |
2e80a82a PZ |
10612 | } |
10613 | pmu->type = type; | |
10614 | ||
abe43400 PZ |
10615 | if (pmu_bus_running) { |
10616 | ret = pmu_dev_alloc(pmu); | |
10617 | if (ret) | |
10618 | goto free_idr; | |
10619 | } | |
10620 | ||
2e80a82a | 10621 | skip_type: |
26657848 PZ |
10622 | if (pmu->task_ctx_nr == perf_hw_context) { |
10623 | static int hw_context_taken = 0; | |
10624 | ||
5101ef20 MR |
10625 | /* |
10626 | * Other than systems with heterogeneous CPUs, it never makes | |
10627 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10628 | * uncore must use perf_invalid_context. | |
10629 | */ | |
10630 | if (WARN_ON_ONCE(hw_context_taken && | |
10631 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10632 | pmu->task_ctx_nr = perf_invalid_context; |
10633 | ||
10634 | hw_context_taken = 1; | |
10635 | } | |
10636 | ||
8dc85d54 PZ |
10637 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10638 | if (pmu->pmu_cpu_context) | |
10639 | goto got_cpu_context; | |
f29ac756 | 10640 | |
c4814202 | 10641 | ret = -ENOMEM; |
108b02cf PZ |
10642 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10643 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10644 | goto free_dev; |
f344011c | 10645 | |
108b02cf PZ |
10646 | for_each_possible_cpu(cpu) { |
10647 | struct perf_cpu_context *cpuctx; | |
10648 | ||
10649 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10650 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10651 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10652 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10653 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10654 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10655 | |
272325c4 | 10656 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
10657 | |
10658 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
10659 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 10660 | } |
76e1d904 | 10661 | |
8dc85d54 | 10662 | got_cpu_context: |
ad5133b7 PZ |
10663 | if (!pmu->start_txn) { |
10664 | if (pmu->pmu_enable) { | |
10665 | /* | |
10666 | * If we have pmu_enable/pmu_disable calls, install | |
10667 | * transaction stubs that use that to try and batch | |
10668 | * hardware accesses. | |
10669 | */ | |
10670 | pmu->start_txn = perf_pmu_start_txn; | |
10671 | pmu->commit_txn = perf_pmu_commit_txn; | |
10672 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10673 | } else { | |
fbbe0701 | 10674 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10675 | pmu->commit_txn = perf_pmu_nop_int; |
10676 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10677 | } |
5c92d124 | 10678 | } |
15dbf27c | 10679 | |
ad5133b7 PZ |
10680 | if (!pmu->pmu_enable) { |
10681 | pmu->pmu_enable = perf_pmu_nop_void; | |
10682 | pmu->pmu_disable = perf_pmu_nop_void; | |
10683 | } | |
10684 | ||
81ec3f3c JO |
10685 | if (!pmu->check_period) |
10686 | pmu->check_period = perf_event_nop_int; | |
10687 | ||
35edc2a5 PZ |
10688 | if (!pmu->event_idx) |
10689 | pmu->event_idx = perf_event_idx_default; | |
10690 | ||
d44f821b LK |
10691 | /* |
10692 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10693 | * since these cannot be in the IDR. This way the linear search | |
10694 | * is fast, provided a valid software event is provided. | |
10695 | */ | |
10696 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10697 | list_add_rcu(&pmu->entry, &pmus); | |
10698 | else | |
10699 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10700 | ||
bed5b25a | 10701 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10702 | ret = 0; |
10703 | unlock: | |
b0a873eb PZ |
10704 | mutex_unlock(&pmus_lock); |
10705 | ||
33696fc0 | 10706 | return ret; |
108b02cf | 10707 | |
abe43400 PZ |
10708 | free_dev: |
10709 | device_del(pmu->dev); | |
10710 | put_device(pmu->dev); | |
10711 | ||
2e80a82a | 10712 | free_idr: |
66d258c5 | 10713 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10714 | idr_remove(&pmu_idr, pmu->type); |
10715 | ||
108b02cf PZ |
10716 | free_pdc: |
10717 | free_percpu(pmu->pmu_disable_count); | |
10718 | goto unlock; | |
f29ac756 | 10719 | } |
c464c76e | 10720 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10721 | |
b0a873eb | 10722 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10723 | { |
b0a873eb PZ |
10724 | mutex_lock(&pmus_lock); |
10725 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10726 | |
0475f9ea | 10727 | /* |
cde8e884 PZ |
10728 | * We dereference the pmu list under both SRCU and regular RCU, so |
10729 | * synchronize against both of those. | |
0475f9ea | 10730 | */ |
b0a873eb | 10731 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10732 | synchronize_rcu(); |
d6d020e9 | 10733 | |
33696fc0 | 10734 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10735 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10736 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10737 | if (pmu_bus_running) { |
0933840a JO |
10738 | if (pmu->nr_addr_filters) |
10739 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10740 | device_del(pmu->dev); | |
10741 | put_device(pmu->dev); | |
10742 | } | |
51676957 | 10743 | free_pmu_context(pmu); |
a9f97721 | 10744 | mutex_unlock(&pmus_lock); |
b0a873eb | 10745 | } |
c464c76e | 10746 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10747 | |
e321d02d KL |
10748 | static inline bool has_extended_regs(struct perf_event *event) |
10749 | { | |
10750 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10751 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10752 | } | |
10753 | ||
cc34b98b MR |
10754 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10755 | { | |
ccd41c86 | 10756 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10757 | int ret; |
10758 | ||
10759 | if (!try_module_get(pmu->module)) | |
10760 | return -ENODEV; | |
ccd41c86 | 10761 | |
0c7296ca PZ |
10762 | /* |
10763 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10764 | * for example, validate if the group fits on the PMU. Therefore, | |
10765 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10766 | * the sibling_list. | |
10767 | */ | |
10768 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10769 | /* |
10770 | * This ctx->mutex can nest when we're called through | |
10771 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10772 | */ | |
10773 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10774 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10775 | BUG_ON(!ctx); |
10776 | } | |
10777 | ||
cc34b98b MR |
10778 | event->pmu = pmu; |
10779 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10780 | |
10781 | if (ctx) | |
10782 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10783 | ||
cc6795ae | 10784 | if (!ret) { |
e321d02d KL |
10785 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10786 | has_extended_regs(event)) | |
10787 | ret = -EOPNOTSUPP; | |
10788 | ||
cc6795ae | 10789 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10790 | event_has_any_exclude_flag(event)) |
cc6795ae | 10791 | ret = -EINVAL; |
e321d02d KL |
10792 | |
10793 | if (ret && event->destroy) | |
10794 | event->destroy(event); | |
cc6795ae AM |
10795 | } |
10796 | ||
cc34b98b MR |
10797 | if (ret) |
10798 | module_put(pmu->module); | |
10799 | ||
10800 | return ret; | |
10801 | } | |
10802 | ||
18ab2cd3 | 10803 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10804 | { |
66d258c5 | 10805 | int idx, type, ret; |
85c617ab | 10806 | struct pmu *pmu; |
b0a873eb PZ |
10807 | |
10808 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10809 | |
40999312 KL |
10810 | /* Try parent's PMU first: */ |
10811 | if (event->parent && event->parent->pmu) { | |
10812 | pmu = event->parent->pmu; | |
10813 | ret = perf_try_init_event(pmu, event); | |
10814 | if (!ret) | |
10815 | goto unlock; | |
10816 | } | |
10817 | ||
66d258c5 PZ |
10818 | /* |
10819 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
10820 | * are often aliases for PERF_TYPE_RAW. | |
10821 | */ | |
10822 | type = event->attr.type; | |
10823 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
10824 | type = PERF_TYPE_RAW; | |
10825 | ||
10826 | again: | |
2e80a82a | 10827 | rcu_read_lock(); |
66d258c5 | 10828 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 10829 | rcu_read_unlock(); |
940c5b29 | 10830 | if (pmu) { |
cc34b98b | 10831 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
10832 | if (ret == -ENOENT && event->attr.type != type) { |
10833 | type = event->attr.type; | |
10834 | goto again; | |
10835 | } | |
10836 | ||
940c5b29 LM |
10837 | if (ret) |
10838 | pmu = ERR_PTR(ret); | |
66d258c5 | 10839 | |
2e80a82a | 10840 | goto unlock; |
940c5b29 | 10841 | } |
2e80a82a | 10842 | |
9f0bff11 | 10843 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 10844 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10845 | if (!ret) |
e5f4d339 | 10846 | goto unlock; |
76e1d904 | 10847 | |
b0a873eb PZ |
10848 | if (ret != -ENOENT) { |
10849 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10850 | goto unlock; |
f344011c | 10851 | } |
5c92d124 | 10852 | } |
e5f4d339 PZ |
10853 | pmu = ERR_PTR(-ENOENT); |
10854 | unlock: | |
b0a873eb | 10855 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10856 | |
4aeb0b42 | 10857 | return pmu; |
5c92d124 IM |
10858 | } |
10859 | ||
f2fb6bef KL |
10860 | static void attach_sb_event(struct perf_event *event) |
10861 | { | |
10862 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10863 | ||
10864 | raw_spin_lock(&pel->lock); | |
10865 | list_add_rcu(&event->sb_list, &pel->list); | |
10866 | raw_spin_unlock(&pel->lock); | |
10867 | } | |
10868 | ||
aab5b71e PZ |
10869 | /* |
10870 | * We keep a list of all !task (and therefore per-cpu) events | |
10871 | * that need to receive side-band records. | |
10872 | * | |
10873 | * This avoids having to scan all the various PMU per-cpu contexts | |
10874 | * looking for them. | |
10875 | */ | |
f2fb6bef KL |
10876 | static void account_pmu_sb_event(struct perf_event *event) |
10877 | { | |
a4f144eb | 10878 | if (is_sb_event(event)) |
f2fb6bef KL |
10879 | attach_sb_event(event); |
10880 | } | |
10881 | ||
4beb31f3 FW |
10882 | static void account_event_cpu(struct perf_event *event, int cpu) |
10883 | { | |
10884 | if (event->parent) | |
10885 | return; | |
10886 | ||
4beb31f3 FW |
10887 | if (is_cgroup_event(event)) |
10888 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10889 | } | |
10890 | ||
555e0c1e FW |
10891 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10892 | static void account_freq_event_nohz(void) | |
10893 | { | |
10894 | #ifdef CONFIG_NO_HZ_FULL | |
10895 | /* Lock so we don't race with concurrent unaccount */ | |
10896 | spin_lock(&nr_freq_lock); | |
10897 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10898 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10899 | spin_unlock(&nr_freq_lock); | |
10900 | #endif | |
10901 | } | |
10902 | ||
10903 | static void account_freq_event(void) | |
10904 | { | |
10905 | if (tick_nohz_full_enabled()) | |
10906 | account_freq_event_nohz(); | |
10907 | else | |
10908 | atomic_inc(&nr_freq_events); | |
10909 | } | |
10910 | ||
10911 | ||
766d6c07 FW |
10912 | static void account_event(struct perf_event *event) |
10913 | { | |
25432ae9 PZ |
10914 | bool inc = false; |
10915 | ||
4beb31f3 FW |
10916 | if (event->parent) |
10917 | return; | |
10918 | ||
766d6c07 | 10919 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10920 | inc = true; |
766d6c07 FW |
10921 | if (event->attr.mmap || event->attr.mmap_data) |
10922 | atomic_inc(&nr_mmap_events); | |
10923 | if (event->attr.comm) | |
10924 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10925 | if (event->attr.namespaces) |
10926 | atomic_inc(&nr_namespaces_events); | |
96aaab68 NK |
10927 | if (event->attr.cgroup) |
10928 | atomic_inc(&nr_cgroup_events); | |
766d6c07 FW |
10929 | if (event->attr.task) |
10930 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10931 | if (event->attr.freq) |
10932 | account_freq_event(); | |
45ac1403 AH |
10933 | if (event->attr.context_switch) { |
10934 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10935 | inc = true; |
45ac1403 | 10936 | } |
4beb31f3 | 10937 | if (has_branch_stack(event)) |
25432ae9 | 10938 | inc = true; |
4beb31f3 | 10939 | if (is_cgroup_event(event)) |
25432ae9 | 10940 | inc = true; |
76193a94 SL |
10941 | if (event->attr.ksymbol) |
10942 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10943 | if (event->attr.bpf_event) |
10944 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10945 | |
9107c89e | 10946 | if (inc) { |
5bce9db1 AS |
10947 | /* |
10948 | * We need the mutex here because static_branch_enable() | |
10949 | * must complete *before* the perf_sched_count increment | |
10950 | * becomes visible. | |
10951 | */ | |
9107c89e PZ |
10952 | if (atomic_inc_not_zero(&perf_sched_count)) |
10953 | goto enabled; | |
10954 | ||
10955 | mutex_lock(&perf_sched_mutex); | |
10956 | if (!atomic_read(&perf_sched_count)) { | |
10957 | static_branch_enable(&perf_sched_events); | |
10958 | /* | |
10959 | * Guarantee that all CPUs observe they key change and | |
10960 | * call the perf scheduling hooks before proceeding to | |
10961 | * install events that need them. | |
10962 | */ | |
0809d954 | 10963 | synchronize_rcu(); |
9107c89e PZ |
10964 | } |
10965 | /* | |
10966 | * Now that we have waited for the sync_sched(), allow further | |
10967 | * increments to by-pass the mutex. | |
10968 | */ | |
10969 | atomic_inc(&perf_sched_count); | |
10970 | mutex_unlock(&perf_sched_mutex); | |
10971 | } | |
10972 | enabled: | |
4beb31f3 FW |
10973 | |
10974 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10975 | |
10976 | account_pmu_sb_event(event); | |
766d6c07 FW |
10977 | } |
10978 | ||
0793a61d | 10979 | /* |
788faab7 | 10980 | * Allocate and initialize an event structure |
0793a61d | 10981 | */ |
cdd6c482 | 10982 | static struct perf_event * |
c3f00c70 | 10983 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10984 | struct task_struct *task, |
10985 | struct perf_event *group_leader, | |
10986 | struct perf_event *parent_event, | |
4dc0da86 | 10987 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10988 | void *context, int cgroup_fd) |
0793a61d | 10989 | { |
51b0fe39 | 10990 | struct pmu *pmu; |
cdd6c482 IM |
10991 | struct perf_event *event; |
10992 | struct hw_perf_event *hwc; | |
90983b16 | 10993 | long err = -EINVAL; |
0793a61d | 10994 | |
66832eb4 ON |
10995 | if ((unsigned)cpu >= nr_cpu_ids) { |
10996 | if (!task || cpu != -1) | |
10997 | return ERR_PTR(-EINVAL); | |
10998 | } | |
10999 | ||
c3f00c70 | 11000 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 11001 | if (!event) |
d5d2bc0d | 11002 | return ERR_PTR(-ENOMEM); |
0793a61d | 11003 | |
04289bb9 | 11004 | /* |
cdd6c482 | 11005 | * Single events are their own group leaders, with an |
04289bb9 IM |
11006 | * empty sibling list: |
11007 | */ | |
11008 | if (!group_leader) | |
cdd6c482 | 11009 | group_leader = event; |
04289bb9 | 11010 | |
cdd6c482 IM |
11011 | mutex_init(&event->child_mutex); |
11012 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 11013 | |
cdd6c482 IM |
11014 | INIT_LIST_HEAD(&event->event_entry); |
11015 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 11016 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 11017 | init_event_group(event); |
10c6db11 | 11018 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 11019 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 11020 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
11021 | INIT_HLIST_NODE(&event->hlist_entry); |
11022 | ||
10c6db11 | 11023 | |
cdd6c482 | 11024 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 11025 | event->pending_disable = -1; |
e360adbe | 11026 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 11027 | |
cdd6c482 | 11028 | mutex_init(&event->mmap_mutex); |
375637bc | 11029 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 11030 | |
a6fa941d | 11031 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
11032 | event->cpu = cpu; |
11033 | event->attr = *attr; | |
11034 | event->group_leader = group_leader; | |
11035 | event->pmu = NULL; | |
cdd6c482 | 11036 | event->oncpu = -1; |
a96bbc16 | 11037 | |
cdd6c482 | 11038 | event->parent = parent_event; |
b84fbc9f | 11039 | |
17cf22c3 | 11040 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 11041 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 11042 | |
cdd6c482 | 11043 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 11044 | |
d580ff86 PZ |
11045 | if (task) { |
11046 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 11047 | /* |
50f16a8b PZ |
11048 | * XXX pmu::event_init needs to know what task to account to |
11049 | * and we cannot use the ctx information because we need the | |
11050 | * pmu before we get a ctx. | |
d580ff86 | 11051 | */ |
7b3c92b8 | 11052 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
11053 | } |
11054 | ||
34f43927 PZ |
11055 | event->clock = &local_clock; |
11056 | if (parent_event) | |
11057 | event->clock = parent_event->clock; | |
11058 | ||
4dc0da86 | 11059 | if (!overflow_handler && parent_event) { |
b326e956 | 11060 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 11061 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 11062 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 11063 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 11064 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 11065 | |
85192dbf | 11066 | bpf_prog_inc(prog); |
aa6a5f3c AS |
11067 | event->prog = prog; |
11068 | event->orig_overflow_handler = | |
11069 | parent_event->orig_overflow_handler; | |
11070 | } | |
11071 | #endif | |
4dc0da86 | 11072 | } |
66832eb4 | 11073 | |
1879445d WN |
11074 | if (overflow_handler) { |
11075 | event->overflow_handler = overflow_handler; | |
11076 | event->overflow_handler_context = context; | |
9ecda41a WN |
11077 | } else if (is_write_backward(event)){ |
11078 | event->overflow_handler = perf_event_output_backward; | |
11079 | event->overflow_handler_context = NULL; | |
1879445d | 11080 | } else { |
9ecda41a | 11081 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
11082 | event->overflow_handler_context = NULL; |
11083 | } | |
97eaf530 | 11084 | |
0231bb53 | 11085 | perf_event__state_init(event); |
a86ed508 | 11086 | |
4aeb0b42 | 11087 | pmu = NULL; |
b8e83514 | 11088 | |
cdd6c482 | 11089 | hwc = &event->hw; |
bd2b5b12 | 11090 | hwc->sample_period = attr->sample_period; |
0d48696f | 11091 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 11092 | hwc->sample_period = 1; |
eced1dfc | 11093 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 11094 | |
e7850595 | 11095 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 11096 | |
2023b359 | 11097 | /* |
ba5213ae PZ |
11098 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
11099 | * See perf_output_read(). | |
2023b359 | 11100 | */ |
ba5213ae | 11101 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 11102 | goto err_ns; |
a46a2300 YZ |
11103 | |
11104 | if (!has_branch_stack(event)) | |
11105 | event->attr.branch_sample_type = 0; | |
2023b359 | 11106 | |
b0a873eb | 11107 | pmu = perf_init_event(event); |
85c617ab | 11108 | if (IS_ERR(pmu)) { |
4aeb0b42 | 11109 | err = PTR_ERR(pmu); |
90983b16 | 11110 | goto err_ns; |
621a01ea | 11111 | } |
d5d2bc0d | 11112 | |
09f4e8f0 PZ |
11113 | /* |
11114 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
11115 | * be different on other CPUs in the uncore mask. | |
11116 | */ | |
11117 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
11118 | err = -EINVAL; | |
11119 | goto err_pmu; | |
11120 | } | |
11121 | ||
ab43762e AS |
11122 | if (event->attr.aux_output && |
11123 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
11124 | err = -EOPNOTSUPP; | |
11125 | goto err_pmu; | |
11126 | } | |
11127 | ||
98add2af PZ |
11128 | if (cgroup_fd != -1) { |
11129 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
11130 | if (err) | |
11131 | goto err_pmu; | |
11132 | } | |
11133 | ||
bed5b25a AS |
11134 | err = exclusive_event_init(event); |
11135 | if (err) | |
11136 | goto err_pmu; | |
11137 | ||
375637bc | 11138 | if (has_addr_filter(event)) { |
c60f83b8 AS |
11139 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
11140 | sizeof(struct perf_addr_filter_range), | |
11141 | GFP_KERNEL); | |
11142 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 11143 | err = -ENOMEM; |
375637bc | 11144 | goto err_per_task; |
36cc2b92 | 11145 | } |
375637bc | 11146 | |
18736eef AS |
11147 | /* |
11148 | * Clone the parent's vma offsets: they are valid until exec() | |
11149 | * even if the mm is not shared with the parent. | |
11150 | */ | |
11151 | if (event->parent) { | |
11152 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11153 | ||
11154 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11155 | memcpy(event->addr_filter_ranges, |
11156 | event->parent->addr_filter_ranges, | |
11157 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11158 | raw_spin_unlock_irq(&ifh->lock); |
11159 | } | |
11160 | ||
375637bc AS |
11161 | /* force hw sync on the address filters */ |
11162 | event->addr_filters_gen = 1; | |
11163 | } | |
11164 | ||
cdd6c482 | 11165 | if (!event->parent) { |
927c7a9e | 11166 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11167 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11168 | if (err) |
375637bc | 11169 | goto err_addr_filters; |
d010b332 | 11170 | } |
f344011c | 11171 | } |
9ee318a7 | 11172 | |
da97e184 JFG |
11173 | err = security_perf_event_alloc(event); |
11174 | if (err) | |
11175 | goto err_callchain_buffer; | |
11176 | ||
927a5570 AS |
11177 | /* symmetric to unaccount_event() in _free_event() */ |
11178 | account_event(event); | |
11179 | ||
cdd6c482 | 11180 | return event; |
90983b16 | 11181 | |
da97e184 JFG |
11182 | err_callchain_buffer: |
11183 | if (!event->parent) { | |
11184 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11185 | put_callchain_buffers(); | |
11186 | } | |
375637bc | 11187 | err_addr_filters: |
c60f83b8 | 11188 | kfree(event->addr_filter_ranges); |
375637bc | 11189 | |
bed5b25a AS |
11190 | err_per_task: |
11191 | exclusive_event_destroy(event); | |
11192 | ||
90983b16 | 11193 | err_pmu: |
98add2af PZ |
11194 | if (is_cgroup_event(event)) |
11195 | perf_detach_cgroup(event); | |
90983b16 FW |
11196 | if (event->destroy) |
11197 | event->destroy(event); | |
c464c76e | 11198 | module_put(pmu->module); |
90983b16 FW |
11199 | err_ns: |
11200 | if (event->ns) | |
11201 | put_pid_ns(event->ns); | |
621b6d2e PB |
11202 | if (event->hw.target) |
11203 | put_task_struct(event->hw.target); | |
90983b16 FW |
11204 | kfree(event); |
11205 | ||
11206 | return ERR_PTR(err); | |
0793a61d TG |
11207 | } |
11208 | ||
cdd6c482 IM |
11209 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11210 | struct perf_event_attr *attr) | |
974802ea | 11211 | { |
974802ea | 11212 | u32 size; |
cdf8073d | 11213 | int ret; |
974802ea | 11214 | |
c2ba8f41 | 11215 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11216 | memset(attr, 0, sizeof(*attr)); |
11217 | ||
11218 | ret = get_user(size, &uattr->size); | |
11219 | if (ret) | |
11220 | return ret; | |
11221 | ||
c2ba8f41 AS |
11222 | /* ABI compatibility quirk: */ |
11223 | if (!size) | |
974802ea | 11224 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11225 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11226 | goto err_size; |
11227 | ||
c2ba8f41 AS |
11228 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11229 | if (ret) { | |
11230 | if (ret == -E2BIG) | |
11231 | goto err_size; | |
11232 | return ret; | |
974802ea PZ |
11233 | } |
11234 | ||
f12f42ac MX |
11235 | attr->size = size; |
11236 | ||
a4faf00d | 11237 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11238 | return -EINVAL; |
11239 | ||
11240 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11241 | return -EINVAL; | |
11242 | ||
11243 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11244 | return -EINVAL; | |
11245 | ||
bce38cd5 SE |
11246 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11247 | u64 mask = attr->branch_sample_type; | |
11248 | ||
11249 | /* only using defined bits */ | |
11250 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11251 | return -EINVAL; | |
11252 | ||
11253 | /* at least one branch bit must be set */ | |
11254 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11255 | return -EINVAL; | |
11256 | ||
bce38cd5 SE |
11257 | /* propagate priv level, when not set for branch */ |
11258 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11259 | ||
11260 | /* exclude_kernel checked on syscall entry */ | |
11261 | if (!attr->exclude_kernel) | |
11262 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11263 | ||
11264 | if (!attr->exclude_user) | |
11265 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11266 | ||
11267 | if (!attr->exclude_hv) | |
11268 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11269 | /* | |
11270 | * adjust user setting (for HW filter setup) | |
11271 | */ | |
11272 | attr->branch_sample_type = mask; | |
11273 | } | |
e712209a | 11274 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11275 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11276 | ret = perf_allow_kernel(attr); | |
11277 | if (ret) | |
11278 | return ret; | |
11279 | } | |
bce38cd5 | 11280 | } |
4018994f | 11281 | |
c5ebcedb | 11282 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11283 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11284 | if (ret) |
11285 | return ret; | |
11286 | } | |
11287 | ||
11288 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11289 | if (!arch_perf_have_user_stack_dump()) | |
11290 | return -ENOSYS; | |
11291 | ||
11292 | /* | |
11293 | * We have __u32 type for the size, but so far | |
11294 | * we can only use __u16 as maximum due to the | |
11295 | * __u16 sample size limit. | |
11296 | */ | |
11297 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11298 | return -EINVAL; |
c5ebcedb | 11299 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11300 | return -EINVAL; |
c5ebcedb | 11301 | } |
4018994f | 11302 | |
5f970521 JO |
11303 | if (!attr->sample_max_stack) |
11304 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11305 | ||
60e2364e SE |
11306 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11307 | ret = perf_reg_validate(attr->sample_regs_intr); | |
6546b19f NK |
11308 | |
11309 | #ifndef CONFIG_CGROUP_PERF | |
11310 | if (attr->sample_type & PERF_SAMPLE_CGROUP) | |
11311 | return -EINVAL; | |
11312 | #endif | |
11313 | ||
974802ea PZ |
11314 | out: |
11315 | return ret; | |
11316 | ||
11317 | err_size: | |
11318 | put_user(sizeof(*attr), &uattr->size); | |
11319 | ret = -E2BIG; | |
11320 | goto out; | |
11321 | } | |
11322 | ||
ac9721f3 PZ |
11323 | static int |
11324 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11325 | { |
56de4e8f | 11326 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11327 | int ret = -EINVAL; |
11328 | ||
ac9721f3 | 11329 | if (!output_event) |
a4be7c27 PZ |
11330 | goto set; |
11331 | ||
ac9721f3 PZ |
11332 | /* don't allow circular references */ |
11333 | if (event == output_event) | |
a4be7c27 PZ |
11334 | goto out; |
11335 | ||
0f139300 PZ |
11336 | /* |
11337 | * Don't allow cross-cpu buffers | |
11338 | */ | |
11339 | if (output_event->cpu != event->cpu) | |
11340 | goto out; | |
11341 | ||
11342 | /* | |
76369139 | 11343 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11344 | */ |
11345 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11346 | goto out; | |
11347 | ||
34f43927 PZ |
11348 | /* |
11349 | * Mixing clocks in the same buffer is trouble you don't need. | |
11350 | */ | |
11351 | if (output_event->clock != event->clock) | |
11352 | goto out; | |
11353 | ||
9ecda41a WN |
11354 | /* |
11355 | * Either writing ring buffer from beginning or from end. | |
11356 | * Mixing is not allowed. | |
11357 | */ | |
11358 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11359 | goto out; | |
11360 | ||
45bfb2e5 PZ |
11361 | /* |
11362 | * If both events generate aux data, they must be on the same PMU | |
11363 | */ | |
11364 | if (has_aux(event) && has_aux(output_event) && | |
11365 | event->pmu != output_event->pmu) | |
11366 | goto out; | |
11367 | ||
a4be7c27 | 11368 | set: |
cdd6c482 | 11369 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11370 | /* Can't redirect output if we've got an active mmap() */ |
11371 | if (atomic_read(&event->mmap_count)) | |
11372 | goto unlock; | |
a4be7c27 | 11373 | |
ac9721f3 | 11374 | if (output_event) { |
76369139 FW |
11375 | /* get the rb we want to redirect to */ |
11376 | rb = ring_buffer_get(output_event); | |
11377 | if (!rb) | |
ac9721f3 | 11378 | goto unlock; |
a4be7c27 PZ |
11379 | } |
11380 | ||
b69cf536 | 11381 | ring_buffer_attach(event, rb); |
9bb5d40c | 11382 | |
a4be7c27 | 11383 | ret = 0; |
ac9721f3 PZ |
11384 | unlock: |
11385 | mutex_unlock(&event->mmap_mutex); | |
11386 | ||
a4be7c27 | 11387 | out: |
a4be7c27 PZ |
11388 | return ret; |
11389 | } | |
11390 | ||
f63a8daa PZ |
11391 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11392 | { | |
11393 | if (b < a) | |
11394 | swap(a, b); | |
11395 | ||
11396 | mutex_lock(a); | |
11397 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11398 | } | |
11399 | ||
34f43927 PZ |
11400 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11401 | { | |
11402 | bool nmi_safe = false; | |
11403 | ||
11404 | switch (clk_id) { | |
11405 | case CLOCK_MONOTONIC: | |
11406 | event->clock = &ktime_get_mono_fast_ns; | |
11407 | nmi_safe = true; | |
11408 | break; | |
11409 | ||
11410 | case CLOCK_MONOTONIC_RAW: | |
11411 | event->clock = &ktime_get_raw_fast_ns; | |
11412 | nmi_safe = true; | |
11413 | break; | |
11414 | ||
11415 | case CLOCK_REALTIME: | |
11416 | event->clock = &ktime_get_real_ns; | |
11417 | break; | |
11418 | ||
11419 | case CLOCK_BOOTTIME: | |
9285ec4c | 11420 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11421 | break; |
11422 | ||
11423 | case CLOCK_TAI: | |
9285ec4c | 11424 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11425 | break; |
11426 | ||
11427 | default: | |
11428 | return -EINVAL; | |
11429 | } | |
11430 | ||
11431 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11432 | return -EINVAL; | |
11433 | ||
11434 | return 0; | |
11435 | } | |
11436 | ||
321027c1 PZ |
11437 | /* |
11438 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11439 | * mutexes. | |
11440 | */ | |
11441 | static struct perf_event_context * | |
11442 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11443 | struct perf_event_context *ctx) | |
11444 | { | |
11445 | struct perf_event_context *gctx; | |
11446 | ||
11447 | again: | |
11448 | rcu_read_lock(); | |
11449 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11450 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11451 | rcu_read_unlock(); |
11452 | goto again; | |
11453 | } | |
11454 | rcu_read_unlock(); | |
11455 | ||
11456 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11457 | ||
11458 | if (group_leader->ctx != gctx) { | |
11459 | mutex_unlock(&ctx->mutex); | |
11460 | mutex_unlock(&gctx->mutex); | |
11461 | put_ctx(gctx); | |
11462 | goto again; | |
11463 | } | |
11464 | ||
11465 | return gctx; | |
11466 | } | |
11467 | ||
0793a61d | 11468 | /** |
cdd6c482 | 11469 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11470 | * |
cdd6c482 | 11471 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11472 | * @pid: target pid |
9f66a381 | 11473 | * @cpu: target cpu |
cdd6c482 | 11474 | * @group_fd: group leader event fd |
0793a61d | 11475 | */ |
cdd6c482 IM |
11476 | SYSCALL_DEFINE5(perf_event_open, |
11477 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11478 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11479 | { |
b04243ef PZ |
11480 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11481 | struct perf_event *event, *sibling; | |
cdd6c482 | 11482 | struct perf_event_attr attr; |
f63a8daa | 11483 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 11484 | struct file *event_file = NULL; |
2903ff01 | 11485 | struct fd group = {NULL, 0}; |
38a81da2 | 11486 | struct task_struct *task = NULL; |
89a1e187 | 11487 | struct pmu *pmu; |
ea635c64 | 11488 | int event_fd; |
b04243ef | 11489 | int move_group = 0; |
dc86cabe | 11490 | int err; |
a21b0b35 | 11491 | int f_flags = O_RDWR; |
79dff51e | 11492 | int cgroup_fd = -1; |
0793a61d | 11493 | |
2743a5b0 | 11494 | /* for future expandability... */ |
e5d1367f | 11495 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11496 | return -EINVAL; |
11497 | ||
da97e184 JFG |
11498 | /* Do we allow access to perf_event_open(2) ? */ |
11499 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11500 | if (err) | |
11501 | return err; | |
11502 | ||
dc86cabe IM |
11503 | err = perf_copy_attr(attr_uptr, &attr); |
11504 | if (err) | |
11505 | return err; | |
eab656ae | 11506 | |
0764771d | 11507 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11508 | err = perf_allow_kernel(&attr); |
11509 | if (err) | |
11510 | return err; | |
0764771d PZ |
11511 | } |
11512 | ||
e4222673 HB |
11513 | if (attr.namespaces) { |
11514 | if (!capable(CAP_SYS_ADMIN)) | |
11515 | return -EACCES; | |
11516 | } | |
11517 | ||
df58ab24 | 11518 | if (attr.freq) { |
cdd6c482 | 11519 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11520 | return -EINVAL; |
0819b2e3 PZ |
11521 | } else { |
11522 | if (attr.sample_period & (1ULL << 63)) | |
11523 | return -EINVAL; | |
df58ab24 PZ |
11524 | } |
11525 | ||
fc7ce9c7 | 11526 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11527 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11528 | err = perf_allow_kernel(&attr); | |
11529 | if (err) | |
11530 | return err; | |
11531 | } | |
fc7ce9c7 | 11532 | |
b0c8fdc7 DH |
11533 | err = security_locked_down(LOCKDOWN_PERF); |
11534 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11535 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11536 | return err; | |
11537 | ||
11538 | err = 0; | |
11539 | ||
e5d1367f SE |
11540 | /* |
11541 | * In cgroup mode, the pid argument is used to pass the fd | |
11542 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11543 | * designates the cpu on which to monitor threads from that | |
11544 | * cgroup. | |
11545 | */ | |
11546 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11547 | return -EINVAL; | |
11548 | ||
a21b0b35 YD |
11549 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11550 | f_flags |= O_CLOEXEC; | |
11551 | ||
11552 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11553 | if (event_fd < 0) |
11554 | return event_fd; | |
11555 | ||
ac9721f3 | 11556 | if (group_fd != -1) { |
2903ff01 AV |
11557 | err = perf_fget_light(group_fd, &group); |
11558 | if (err) | |
d14b12d7 | 11559 | goto err_fd; |
2903ff01 | 11560 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11561 | if (flags & PERF_FLAG_FD_OUTPUT) |
11562 | output_event = group_leader; | |
11563 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11564 | group_leader = NULL; | |
11565 | } | |
11566 | ||
e5d1367f | 11567 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11568 | task = find_lively_task_by_vpid(pid); |
11569 | if (IS_ERR(task)) { | |
11570 | err = PTR_ERR(task); | |
11571 | goto err_group_fd; | |
11572 | } | |
11573 | } | |
11574 | ||
1f4ee503 PZ |
11575 | if (task && group_leader && |
11576 | group_leader->attr.inherit != attr.inherit) { | |
11577 | err = -EINVAL; | |
11578 | goto err_task; | |
11579 | } | |
11580 | ||
79c9ce57 | 11581 | if (task) { |
69143038 | 11582 | err = mutex_lock_interruptible(&task->signal->exec_update_mutex); |
79c9ce57 | 11583 | if (err) |
e5aeee51 | 11584 | goto err_task; |
79c9ce57 PZ |
11585 | |
11586 | /* | |
11587 | * Reuse ptrace permission checks for now. | |
11588 | * | |
69143038 | 11589 | * We must hold exec_update_mutex across this and any potential |
79c9ce57 PZ |
11590 | * perf_install_in_context() call for this new event to |
11591 | * serialize against exec() altering our credentials (and the | |
11592 | * perf_event_exit_task() that could imply). | |
11593 | */ | |
11594 | err = -EACCES; | |
11595 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
11596 | goto err_cred; | |
11597 | } | |
11598 | ||
79dff51e MF |
11599 | if (flags & PERF_FLAG_PID_CGROUP) |
11600 | cgroup_fd = pid; | |
11601 | ||
4dc0da86 | 11602 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11603 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11604 | if (IS_ERR(event)) { |
11605 | err = PTR_ERR(event); | |
79c9ce57 | 11606 | goto err_cred; |
d14b12d7 SE |
11607 | } |
11608 | ||
53b25335 VW |
11609 | if (is_sampling_event(event)) { |
11610 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11611 | err = -EOPNOTSUPP; |
53b25335 VW |
11612 | goto err_alloc; |
11613 | } | |
11614 | } | |
11615 | ||
89a1e187 PZ |
11616 | /* |
11617 | * Special case software events and allow them to be part of | |
11618 | * any hardware group. | |
11619 | */ | |
11620 | pmu = event->pmu; | |
b04243ef | 11621 | |
34f43927 PZ |
11622 | if (attr.use_clockid) { |
11623 | err = perf_event_set_clock(event, attr.clockid); | |
11624 | if (err) | |
11625 | goto err_alloc; | |
11626 | } | |
11627 | ||
4ff6a8de DCC |
11628 | if (pmu->task_ctx_nr == perf_sw_context) |
11629 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11630 | ||
a1150c20 SL |
11631 | if (group_leader) { |
11632 | if (is_software_event(event) && | |
11633 | !in_software_context(group_leader)) { | |
b04243ef | 11634 | /* |
a1150c20 SL |
11635 | * If the event is a sw event, but the group_leader |
11636 | * is on hw context. | |
b04243ef | 11637 | * |
a1150c20 SL |
11638 | * Allow the addition of software events to hw |
11639 | * groups, this is safe because software events | |
11640 | * never fail to schedule. | |
b04243ef | 11641 | */ |
a1150c20 SL |
11642 | pmu = group_leader->ctx->pmu; |
11643 | } else if (!is_software_event(event) && | |
11644 | is_software_event(group_leader) && | |
4ff6a8de | 11645 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11646 | /* |
11647 | * In case the group is a pure software group, and we | |
11648 | * try to add a hardware event, move the whole group to | |
11649 | * the hardware context. | |
11650 | */ | |
11651 | move_group = 1; | |
11652 | } | |
11653 | } | |
89a1e187 PZ |
11654 | |
11655 | /* | |
11656 | * Get the target context (task or percpu): | |
11657 | */ | |
4af57ef2 | 11658 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11659 | if (IS_ERR(ctx)) { |
11660 | err = PTR_ERR(ctx); | |
c6be5a5c | 11661 | goto err_alloc; |
89a1e187 PZ |
11662 | } |
11663 | ||
ccff286d | 11664 | /* |
cdd6c482 | 11665 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11666 | */ |
ac9721f3 | 11667 | if (group_leader) { |
dc86cabe | 11668 | err = -EINVAL; |
04289bb9 | 11669 | |
04289bb9 | 11670 | /* |
ccff286d IM |
11671 | * Do not allow a recursive hierarchy (this new sibling |
11672 | * becoming part of another group-sibling): | |
11673 | */ | |
11674 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11675 | goto err_context; |
34f43927 PZ |
11676 | |
11677 | /* All events in a group should have the same clock */ | |
11678 | if (group_leader->clock != event->clock) | |
11679 | goto err_context; | |
11680 | ||
ccff286d | 11681 | /* |
64aee2a9 MR |
11682 | * Make sure we're both events for the same CPU; |
11683 | * grouping events for different CPUs is broken; since | |
11684 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11685 | */ |
64aee2a9 MR |
11686 | if (group_leader->cpu != event->cpu) |
11687 | goto err_context; | |
c3c87e77 | 11688 | |
64aee2a9 MR |
11689 | /* |
11690 | * Make sure we're both on the same task, or both | |
11691 | * per-CPU events. | |
11692 | */ | |
11693 | if (group_leader->ctx->task != ctx->task) | |
11694 | goto err_context; | |
11695 | ||
11696 | /* | |
11697 | * Do not allow to attach to a group in a different task | |
11698 | * or CPU context. If we're moving SW events, we'll fix | |
11699 | * this up later, so allow that. | |
11700 | */ | |
11701 | if (!move_group && group_leader->ctx != ctx) | |
11702 | goto err_context; | |
b04243ef | 11703 | |
3b6f9e5c PM |
11704 | /* |
11705 | * Only a group leader can be exclusive or pinned | |
11706 | */ | |
0d48696f | 11707 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11708 | goto err_context; |
ac9721f3 PZ |
11709 | } |
11710 | ||
11711 | if (output_event) { | |
11712 | err = perf_event_set_output(event, output_event); | |
11713 | if (err) | |
c3f00c70 | 11714 | goto err_context; |
ac9721f3 | 11715 | } |
0793a61d | 11716 | |
a21b0b35 YD |
11717 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11718 | f_flags); | |
ea635c64 AV |
11719 | if (IS_ERR(event_file)) { |
11720 | err = PTR_ERR(event_file); | |
201c2f85 | 11721 | event_file = NULL; |
c3f00c70 | 11722 | goto err_context; |
ea635c64 | 11723 | } |
9b51f66d | 11724 | |
b04243ef | 11725 | if (move_group) { |
321027c1 PZ |
11726 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11727 | ||
84c4e620 PZ |
11728 | if (gctx->task == TASK_TOMBSTONE) { |
11729 | err = -ESRCH; | |
11730 | goto err_locked; | |
11731 | } | |
321027c1 PZ |
11732 | |
11733 | /* | |
11734 | * Check if we raced against another sys_perf_event_open() call | |
11735 | * moving the software group underneath us. | |
11736 | */ | |
11737 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11738 | /* | |
11739 | * If someone moved the group out from under us, check | |
11740 | * if this new event wound up on the same ctx, if so | |
11741 | * its the regular !move_group case, otherwise fail. | |
11742 | */ | |
11743 | if (gctx != ctx) { | |
11744 | err = -EINVAL; | |
11745 | goto err_locked; | |
11746 | } else { | |
11747 | perf_event_ctx_unlock(group_leader, gctx); | |
11748 | move_group = 0; | |
11749 | } | |
11750 | } | |
8a58ddae AS |
11751 | |
11752 | /* | |
11753 | * Failure to create exclusive events returns -EBUSY. | |
11754 | */ | |
11755 | err = -EBUSY; | |
11756 | if (!exclusive_event_installable(group_leader, ctx)) | |
11757 | goto err_locked; | |
11758 | ||
11759 | for_each_sibling_event(sibling, group_leader) { | |
11760 | if (!exclusive_event_installable(sibling, ctx)) | |
11761 | goto err_locked; | |
11762 | } | |
f55fc2a5 PZ |
11763 | } else { |
11764 | mutex_lock(&ctx->mutex); | |
11765 | } | |
11766 | ||
84c4e620 PZ |
11767 | if (ctx->task == TASK_TOMBSTONE) { |
11768 | err = -ESRCH; | |
11769 | goto err_locked; | |
11770 | } | |
11771 | ||
a723968c PZ |
11772 | if (!perf_event_validate_size(event)) { |
11773 | err = -E2BIG; | |
11774 | goto err_locked; | |
11775 | } | |
11776 | ||
a63fbed7 TG |
11777 | if (!task) { |
11778 | /* | |
11779 | * Check if the @cpu we're creating an event for is online. | |
11780 | * | |
11781 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11782 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11783 | */ | |
11784 | struct perf_cpu_context *cpuctx = | |
11785 | container_of(ctx, struct perf_cpu_context, ctx); | |
11786 | ||
11787 | if (!cpuctx->online) { | |
11788 | err = -ENODEV; | |
11789 | goto err_locked; | |
11790 | } | |
11791 | } | |
11792 | ||
da9ec3d3 MR |
11793 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
11794 | err = -EINVAL; | |
ab43762e | 11795 | goto err_locked; |
da9ec3d3 | 11796 | } |
a63fbed7 | 11797 | |
f55fc2a5 PZ |
11798 | /* |
11799 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11800 | * because we need to serialize with concurrent event creation. | |
11801 | */ | |
11802 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11803 | err = -EBUSY; |
11804 | goto err_locked; | |
11805 | } | |
f63a8daa | 11806 | |
f55fc2a5 PZ |
11807 | WARN_ON_ONCE(ctx->parent_ctx); |
11808 | ||
79c9ce57 PZ |
11809 | /* |
11810 | * This is the point on no return; we cannot fail hereafter. This is | |
11811 | * where we start modifying current state. | |
11812 | */ | |
11813 | ||
f55fc2a5 | 11814 | if (move_group) { |
f63a8daa PZ |
11815 | /* |
11816 | * See perf_event_ctx_lock() for comments on the details | |
11817 | * of swizzling perf_event::ctx. | |
11818 | */ | |
45a0e07a | 11819 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11820 | put_ctx(gctx); |
0231bb53 | 11821 | |
edb39592 | 11822 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11823 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11824 | put_ctx(gctx); |
11825 | } | |
b04243ef | 11826 | |
f63a8daa PZ |
11827 | /* |
11828 | * Wait for everybody to stop referencing the events through | |
11829 | * the old lists, before installing it on new lists. | |
11830 | */ | |
0cda4c02 | 11831 | synchronize_rcu(); |
f63a8daa | 11832 | |
8f95b435 PZI |
11833 | /* |
11834 | * Install the group siblings before the group leader. | |
11835 | * | |
11836 | * Because a group leader will try and install the entire group | |
11837 | * (through the sibling list, which is still in-tact), we can | |
11838 | * end up with siblings installed in the wrong context. | |
11839 | * | |
11840 | * By installing siblings first we NO-OP because they're not | |
11841 | * reachable through the group lists. | |
11842 | */ | |
edb39592 | 11843 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11844 | perf_event__state_init(sibling); |
9fc81d87 | 11845 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11846 | get_ctx(ctx); |
11847 | } | |
8f95b435 PZI |
11848 | |
11849 | /* | |
11850 | * Removing from the context ends up with disabled | |
11851 | * event. What we want here is event in the initial | |
11852 | * startup state, ready to be add into new context. | |
11853 | */ | |
11854 | perf_event__state_init(group_leader); | |
11855 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11856 | get_ctx(ctx); | |
bed5b25a AS |
11857 | } |
11858 | ||
f73e22ab PZ |
11859 | /* |
11860 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11861 | * that we're serialized against further additions and before | |
11862 | * perf_install_in_context() which is the point the event is active and | |
11863 | * can use these values. | |
11864 | */ | |
11865 | perf_event__header_size(event); | |
11866 | perf_event__id_header_size(event); | |
11867 | ||
78cd2c74 PZ |
11868 | event->owner = current; |
11869 | ||
e2d37cd2 | 11870 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11871 | perf_unpin_context(ctx); |
f63a8daa | 11872 | |
f55fc2a5 | 11873 | if (move_group) |
321027c1 | 11874 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11875 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11876 | |
79c9ce57 | 11877 | if (task) { |
69143038 | 11878 | mutex_unlock(&task->signal->exec_update_mutex); |
79c9ce57 PZ |
11879 | put_task_struct(task); |
11880 | } | |
11881 | ||
cdd6c482 IM |
11882 | mutex_lock(¤t->perf_event_mutex); |
11883 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11884 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11885 | |
8a49542c PZ |
11886 | /* |
11887 | * Drop the reference on the group_event after placing the | |
11888 | * new event on the sibling_list. This ensures destruction | |
11889 | * of the group leader will find the pointer to itself in | |
11890 | * perf_group_detach(). | |
11891 | */ | |
2903ff01 | 11892 | fdput(group); |
ea635c64 AV |
11893 | fd_install(event_fd, event_file); |
11894 | return event_fd; | |
0793a61d | 11895 | |
f55fc2a5 PZ |
11896 | err_locked: |
11897 | if (move_group) | |
321027c1 | 11898 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11899 | mutex_unlock(&ctx->mutex); |
11900 | /* err_file: */ | |
11901 | fput(event_file); | |
c3f00c70 | 11902 | err_context: |
fe4b04fa | 11903 | perf_unpin_context(ctx); |
ea635c64 | 11904 | put_ctx(ctx); |
c6be5a5c | 11905 | err_alloc: |
13005627 PZ |
11906 | /* |
11907 | * If event_file is set, the fput() above will have called ->release() | |
11908 | * and that will take care of freeing the event. | |
11909 | */ | |
11910 | if (!event_file) | |
11911 | free_event(event); | |
79c9ce57 PZ |
11912 | err_cred: |
11913 | if (task) | |
69143038 | 11914 | mutex_unlock(&task->signal->exec_update_mutex); |
1f4ee503 | 11915 | err_task: |
e7d0bc04 PZ |
11916 | if (task) |
11917 | put_task_struct(task); | |
89a1e187 | 11918 | err_group_fd: |
2903ff01 | 11919 | fdput(group); |
ea635c64 AV |
11920 | err_fd: |
11921 | put_unused_fd(event_fd); | |
dc86cabe | 11922 | return err; |
0793a61d TG |
11923 | } |
11924 | ||
fb0459d7 AV |
11925 | /** |
11926 | * perf_event_create_kernel_counter | |
11927 | * | |
11928 | * @attr: attributes of the counter to create | |
11929 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11930 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11931 | */ |
11932 | struct perf_event * | |
11933 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11934 | struct task_struct *task, |
4dc0da86 AK |
11935 | perf_overflow_handler_t overflow_handler, |
11936 | void *context) | |
fb0459d7 | 11937 | { |
fb0459d7 | 11938 | struct perf_event_context *ctx; |
c3f00c70 | 11939 | struct perf_event *event; |
fb0459d7 | 11940 | int err; |
d859e29f | 11941 | |
dce5affb AS |
11942 | /* |
11943 | * Grouping is not supported for kernel events, neither is 'AUX', | |
11944 | * make sure the caller's intentions are adjusted. | |
11945 | */ | |
11946 | if (attr->aux_output) | |
11947 | return ERR_PTR(-EINVAL); | |
11948 | ||
4dc0da86 | 11949 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11950 | overflow_handler, context, -1); |
c3f00c70 PZ |
11951 | if (IS_ERR(event)) { |
11952 | err = PTR_ERR(event); | |
11953 | goto err; | |
11954 | } | |
d859e29f | 11955 | |
f8697762 | 11956 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11957 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11958 | |
f25d8ba9 AS |
11959 | /* |
11960 | * Get the target context (task or percpu): | |
11961 | */ | |
4af57ef2 | 11962 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11963 | if (IS_ERR(ctx)) { |
11964 | err = PTR_ERR(ctx); | |
c3f00c70 | 11965 | goto err_free; |
d859e29f | 11966 | } |
fb0459d7 | 11967 | |
fb0459d7 AV |
11968 | WARN_ON_ONCE(ctx->parent_ctx); |
11969 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11970 | if (ctx->task == TASK_TOMBSTONE) { |
11971 | err = -ESRCH; | |
11972 | goto err_unlock; | |
11973 | } | |
11974 | ||
a63fbed7 TG |
11975 | if (!task) { |
11976 | /* | |
11977 | * Check if the @cpu we're creating an event for is online. | |
11978 | * | |
11979 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11980 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11981 | */ | |
11982 | struct perf_cpu_context *cpuctx = | |
11983 | container_of(ctx, struct perf_cpu_context, ctx); | |
11984 | if (!cpuctx->online) { | |
11985 | err = -ENODEV; | |
11986 | goto err_unlock; | |
11987 | } | |
11988 | } | |
11989 | ||
bed5b25a | 11990 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11991 | err = -EBUSY; |
84c4e620 | 11992 | goto err_unlock; |
bed5b25a AS |
11993 | } |
11994 | ||
4ce54af8 | 11995 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11996 | perf_unpin_context(ctx); |
fb0459d7 AV |
11997 | mutex_unlock(&ctx->mutex); |
11998 | ||
fb0459d7 AV |
11999 | return event; |
12000 | ||
84c4e620 PZ |
12001 | err_unlock: |
12002 | mutex_unlock(&ctx->mutex); | |
12003 | perf_unpin_context(ctx); | |
12004 | put_ctx(ctx); | |
c3f00c70 PZ |
12005 | err_free: |
12006 | free_event(event); | |
12007 | err: | |
c6567f64 | 12008 | return ERR_PTR(err); |
9b51f66d | 12009 | } |
fb0459d7 | 12010 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 12011 | |
0cda4c02 YZ |
12012 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
12013 | { | |
12014 | struct perf_event_context *src_ctx; | |
12015 | struct perf_event_context *dst_ctx; | |
12016 | struct perf_event *event, *tmp; | |
12017 | LIST_HEAD(events); | |
12018 | ||
12019 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
12020 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
12021 | ||
f63a8daa PZ |
12022 | /* |
12023 | * See perf_event_ctx_lock() for comments on the details | |
12024 | * of swizzling perf_event::ctx. | |
12025 | */ | |
12026 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
12027 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
12028 | event_entry) { | |
45a0e07a | 12029 | perf_remove_from_context(event, 0); |
9a545de0 | 12030 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 12031 | put_ctx(src_ctx); |
9886167d | 12032 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 12033 | } |
0cda4c02 | 12034 | |
8f95b435 PZI |
12035 | /* |
12036 | * Wait for the events to quiesce before re-instating them. | |
12037 | */ | |
0cda4c02 YZ |
12038 | synchronize_rcu(); |
12039 | ||
8f95b435 PZI |
12040 | /* |
12041 | * Re-instate events in 2 passes. | |
12042 | * | |
12043 | * Skip over group leaders and only install siblings on this first | |
12044 | * pass, siblings will not get enabled without a leader, however a | |
12045 | * leader will enable its siblings, even if those are still on the old | |
12046 | * context. | |
12047 | */ | |
12048 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
12049 | if (event->group_leader == event) | |
12050 | continue; | |
12051 | ||
12052 | list_del(&event->migrate_entry); | |
12053 | if (event->state >= PERF_EVENT_STATE_OFF) | |
12054 | event->state = PERF_EVENT_STATE_INACTIVE; | |
12055 | account_event_cpu(event, dst_cpu); | |
12056 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
12057 | get_ctx(dst_ctx); | |
12058 | } | |
12059 | ||
12060 | /* | |
12061 | * Once all the siblings are setup properly, install the group leaders | |
12062 | * to make it go. | |
12063 | */ | |
9886167d PZ |
12064 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
12065 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
12066 | if (event->state >= PERF_EVENT_STATE_OFF) |
12067 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 12068 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
12069 | perf_install_in_context(dst_ctx, event, dst_cpu); |
12070 | get_ctx(dst_ctx); | |
12071 | } | |
12072 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 12073 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
12074 | } |
12075 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
12076 | ||
cdd6c482 | 12077 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 12078 | struct task_struct *child) |
d859e29f | 12079 | { |
cdd6c482 | 12080 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 12081 | u64 child_val; |
d859e29f | 12082 | |
cdd6c482 IM |
12083 | if (child_event->attr.inherit_stat) |
12084 | perf_event_read_event(child_event, child); | |
38b200d6 | 12085 | |
b5e58793 | 12086 | child_val = perf_event_count(child_event); |
d859e29f PM |
12087 | |
12088 | /* | |
12089 | * Add back the child's count to the parent's count: | |
12090 | */ | |
a6e6dea6 | 12091 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
12092 | atomic64_add(child_event->total_time_enabled, |
12093 | &parent_event->child_total_time_enabled); | |
12094 | atomic64_add(child_event->total_time_running, | |
12095 | &parent_event->child_total_time_running); | |
d859e29f PM |
12096 | } |
12097 | ||
9b51f66d | 12098 | static void |
8ba289b8 PZ |
12099 | perf_event_exit_event(struct perf_event *child_event, |
12100 | struct perf_event_context *child_ctx, | |
12101 | struct task_struct *child) | |
9b51f66d | 12102 | { |
8ba289b8 PZ |
12103 | struct perf_event *parent_event = child_event->parent; |
12104 | ||
1903d50c PZ |
12105 | /* |
12106 | * Do not destroy the 'original' grouping; because of the context | |
12107 | * switch optimization the original events could've ended up in a | |
12108 | * random child task. | |
12109 | * | |
12110 | * If we were to destroy the original group, all group related | |
12111 | * operations would cease to function properly after this random | |
12112 | * child dies. | |
12113 | * | |
12114 | * Do destroy all inherited groups, we don't care about those | |
12115 | * and being thorough is better. | |
12116 | */ | |
32132a3d PZ |
12117 | raw_spin_lock_irq(&child_ctx->lock); |
12118 | WARN_ON_ONCE(child_ctx->is_active); | |
12119 | ||
8ba289b8 | 12120 | if (parent_event) |
32132a3d PZ |
12121 | perf_group_detach(child_event); |
12122 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 12123 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 12124 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 12125 | |
9b51f66d | 12126 | /* |
8ba289b8 | 12127 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 12128 | */ |
8ba289b8 | 12129 | if (!parent_event) { |
179033b3 | 12130 | perf_event_wakeup(child_event); |
8ba289b8 | 12131 | return; |
4bcf349a | 12132 | } |
8ba289b8 PZ |
12133 | /* |
12134 | * Child events can be cleaned up. | |
12135 | */ | |
12136 | ||
12137 | sync_child_event(child_event, child); | |
12138 | ||
12139 | /* | |
12140 | * Remove this event from the parent's list | |
12141 | */ | |
12142 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
12143 | mutex_lock(&parent_event->child_mutex); | |
12144 | list_del_init(&child_event->child_list); | |
12145 | mutex_unlock(&parent_event->child_mutex); | |
12146 | ||
12147 | /* | |
12148 | * Kick perf_poll() for is_event_hup(). | |
12149 | */ | |
12150 | perf_event_wakeup(parent_event); | |
12151 | free_event(child_event); | |
12152 | put_event(parent_event); | |
9b51f66d IM |
12153 | } |
12154 | ||
8dc85d54 | 12155 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12156 | { |
211de6eb | 12157 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12158 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12159 | |
12160 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12161 | |
6a3351b6 | 12162 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12163 | if (!child_ctx) |
9b51f66d IM |
12164 | return; |
12165 | ||
ad3a37de | 12166 | /* |
6a3351b6 PZ |
12167 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12168 | * ctx::mutex over the entire thing. This serializes against almost | |
12169 | * everything that wants to access the ctx. | |
12170 | * | |
12171 | * The exception is sys_perf_event_open() / | |
12172 | * perf_event_create_kernel_count() which does find_get_context() | |
12173 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12174 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12175 | */ |
6a3351b6 | 12176 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12177 | |
12178 | /* | |
6a3351b6 PZ |
12179 | * In a single ctx::lock section, de-schedule the events and detach the |
12180 | * context from the task such that we cannot ever get it scheduled back | |
12181 | * in. | |
c93f7669 | 12182 | */ |
6a3351b6 | 12183 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12184 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12185 | |
71a851b4 | 12186 | /* |
63b6da39 PZ |
12187 | * Now that the context is inactive, destroy the task <-> ctx relation |
12188 | * and mark the context dead. | |
71a851b4 | 12189 | */ |
63b6da39 PZ |
12190 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12191 | put_ctx(child_ctx); /* cannot be last */ | |
12192 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12193 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12194 | |
211de6eb | 12195 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12196 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12197 | |
211de6eb PZ |
12198 | if (clone_ctx) |
12199 | put_ctx(clone_ctx); | |
4a1c0f26 | 12200 | |
9f498cc5 | 12201 | /* |
cdd6c482 IM |
12202 | * Report the task dead after unscheduling the events so that we |
12203 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12204 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12205 | */ |
cdd6c482 | 12206 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12207 | |
ebf905fc | 12208 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 12209 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 12210 | |
a63eaf34 PM |
12211 | mutex_unlock(&child_ctx->mutex); |
12212 | ||
12213 | put_ctx(child_ctx); | |
9b51f66d IM |
12214 | } |
12215 | ||
8dc85d54 PZ |
12216 | /* |
12217 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 | 12218 | * |
69143038 | 12219 | * Can be called with exec_update_mutex held when called from |
79c9ce57 | 12220 | * install_exec_creds(). |
8dc85d54 PZ |
12221 | */ |
12222 | void perf_event_exit_task(struct task_struct *child) | |
12223 | { | |
8882135b | 12224 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12225 | int ctxn; |
12226 | ||
8882135b PZ |
12227 | mutex_lock(&child->perf_event_mutex); |
12228 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12229 | owner_entry) { | |
12230 | list_del_init(&event->owner_entry); | |
12231 | ||
12232 | /* | |
12233 | * Ensure the list deletion is visible before we clear | |
12234 | * the owner, closes a race against perf_release() where | |
12235 | * we need to serialize on the owner->perf_event_mutex. | |
12236 | */ | |
f47c02c0 | 12237 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12238 | } |
12239 | mutex_unlock(&child->perf_event_mutex); | |
12240 | ||
8dc85d54 PZ |
12241 | for_each_task_context_nr(ctxn) |
12242 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12243 | |
12244 | /* | |
12245 | * The perf_event_exit_task_context calls perf_event_task | |
12246 | * with child's task_ctx, which generates EXIT events for | |
12247 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12248 | * At this point we need to send EXIT events to cpu contexts. | |
12249 | */ | |
12250 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12251 | } |
12252 | ||
889ff015 FW |
12253 | static void perf_free_event(struct perf_event *event, |
12254 | struct perf_event_context *ctx) | |
12255 | { | |
12256 | struct perf_event *parent = event->parent; | |
12257 | ||
12258 | if (WARN_ON_ONCE(!parent)) | |
12259 | return; | |
12260 | ||
12261 | mutex_lock(&parent->child_mutex); | |
12262 | list_del_init(&event->child_list); | |
12263 | mutex_unlock(&parent->child_mutex); | |
12264 | ||
a6fa941d | 12265 | put_event(parent); |
889ff015 | 12266 | |
652884fe | 12267 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12268 | perf_group_detach(event); |
889ff015 | 12269 | list_del_event(event, ctx); |
652884fe | 12270 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12271 | free_event(event); |
12272 | } | |
12273 | ||
bbbee908 | 12274 | /* |
1cf8dfe8 PZ |
12275 | * Free a context as created by inheritance by perf_event_init_task() below, |
12276 | * used by fork() in case of fail. | |
652884fe | 12277 | * |
1cf8dfe8 PZ |
12278 | * Even though the task has never lived, the context and events have been |
12279 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12280 | */ |
cdd6c482 | 12281 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12282 | { |
8dc85d54 | 12283 | struct perf_event_context *ctx; |
cdd6c482 | 12284 | struct perf_event *event, *tmp; |
8dc85d54 | 12285 | int ctxn; |
bbbee908 | 12286 | |
8dc85d54 PZ |
12287 | for_each_task_context_nr(ctxn) { |
12288 | ctx = task->perf_event_ctxp[ctxn]; | |
12289 | if (!ctx) | |
12290 | continue; | |
bbbee908 | 12291 | |
8dc85d54 | 12292 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12293 | raw_spin_lock_irq(&ctx->lock); |
12294 | /* | |
12295 | * Destroy the task <-> ctx relation and mark the context dead. | |
12296 | * | |
12297 | * This is important because even though the task hasn't been | |
12298 | * exposed yet the context has been (through child_list). | |
12299 | */ | |
12300 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12301 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12302 | put_task_struct(task); /* cannot be last */ | |
12303 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12304 | |
15121c78 | 12305 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12306 | perf_free_event(event, ctx); |
bbbee908 | 12307 | |
8dc85d54 | 12308 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12309 | |
12310 | /* | |
12311 | * perf_event_release_kernel() could've stolen some of our | |
12312 | * child events and still have them on its free_list. In that | |
12313 | * case we must wait for these events to have been freed (in | |
12314 | * particular all their references to this task must've been | |
12315 | * dropped). | |
12316 | * | |
12317 | * Without this copy_process() will unconditionally free this | |
12318 | * task (irrespective of its reference count) and | |
12319 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12320 | * use-after-free. | |
12321 | * | |
12322 | * Wait for all events to drop their context reference. | |
12323 | */ | |
12324 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12325 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12326 | } |
889ff015 FW |
12327 | } |
12328 | ||
4e231c79 PZ |
12329 | void perf_event_delayed_put(struct task_struct *task) |
12330 | { | |
12331 | int ctxn; | |
12332 | ||
12333 | for_each_task_context_nr(ctxn) | |
12334 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12335 | } | |
12336 | ||
e03e7ee3 | 12337 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12338 | { |
02e5ad97 | 12339 | struct file *file = fget(fd); |
e03e7ee3 AS |
12340 | if (!file) |
12341 | return ERR_PTR(-EBADF); | |
ffe8690c | 12342 | |
e03e7ee3 AS |
12343 | if (file->f_op != &perf_fops) { |
12344 | fput(file); | |
12345 | return ERR_PTR(-EBADF); | |
12346 | } | |
ffe8690c | 12347 | |
e03e7ee3 | 12348 | return file; |
ffe8690c KX |
12349 | } |
12350 | ||
f8d959a5 YS |
12351 | const struct perf_event *perf_get_event(struct file *file) |
12352 | { | |
12353 | if (file->f_op != &perf_fops) | |
12354 | return ERR_PTR(-EINVAL); | |
12355 | ||
12356 | return file->private_data; | |
12357 | } | |
12358 | ||
ffe8690c KX |
12359 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12360 | { | |
12361 | if (!event) | |
12362 | return ERR_PTR(-EINVAL); | |
12363 | ||
12364 | return &event->attr; | |
12365 | } | |
12366 | ||
97dee4f3 | 12367 | /* |
788faab7 | 12368 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12369 | * |
12370 | * Returns: | |
12371 | * - valid pointer on success | |
12372 | * - NULL for orphaned events | |
12373 | * - IS_ERR() on error | |
97dee4f3 PZ |
12374 | */ |
12375 | static struct perf_event * | |
12376 | inherit_event(struct perf_event *parent_event, | |
12377 | struct task_struct *parent, | |
12378 | struct perf_event_context *parent_ctx, | |
12379 | struct task_struct *child, | |
12380 | struct perf_event *group_leader, | |
12381 | struct perf_event_context *child_ctx) | |
12382 | { | |
8ca2bd41 | 12383 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12384 | struct perf_event *child_event; |
cee010ec | 12385 | unsigned long flags; |
97dee4f3 PZ |
12386 | |
12387 | /* | |
12388 | * Instead of creating recursive hierarchies of events, | |
12389 | * we link inherited events back to the original parent, | |
12390 | * which has a filp for sure, which we use as the reference | |
12391 | * count: | |
12392 | */ | |
12393 | if (parent_event->parent) | |
12394 | parent_event = parent_event->parent; | |
12395 | ||
12396 | child_event = perf_event_alloc(&parent_event->attr, | |
12397 | parent_event->cpu, | |
d580ff86 | 12398 | child, |
97dee4f3 | 12399 | group_leader, parent_event, |
79dff51e | 12400 | NULL, NULL, -1); |
97dee4f3 PZ |
12401 | if (IS_ERR(child_event)) |
12402 | return child_event; | |
a6fa941d | 12403 | |
313ccb96 JO |
12404 | |
12405 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12406 | !child_ctx->task_ctx_data) { | |
12407 | struct pmu *pmu = child_event->pmu; | |
12408 | ||
12409 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
12410 | GFP_KERNEL); | |
12411 | if (!child_ctx->task_ctx_data) { | |
12412 | free_event(child_event); | |
697d8778 | 12413 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12414 | } |
12415 | } | |
12416 | ||
c6e5b732 PZ |
12417 | /* |
12418 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12419 | * must be under the same lock in order to serialize against | |
12420 | * perf_event_release_kernel(), such that either we must observe | |
12421 | * is_orphaned_event() or they will observe us on the child_list. | |
12422 | */ | |
12423 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12424 | if (is_orphaned_event(parent_event) || |
12425 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12426 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12427 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12428 | free_event(child_event); |
12429 | return NULL; | |
12430 | } | |
12431 | ||
97dee4f3 PZ |
12432 | get_ctx(child_ctx); |
12433 | ||
12434 | /* | |
12435 | * Make the child state follow the state of the parent event, | |
12436 | * not its attr.disabled bit. We hold the parent's mutex, | |
12437 | * so we won't race with perf_event_{en, dis}able_family. | |
12438 | */ | |
1929def9 | 12439 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12440 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12441 | else | |
12442 | child_event->state = PERF_EVENT_STATE_OFF; | |
12443 | ||
12444 | if (parent_event->attr.freq) { | |
12445 | u64 sample_period = parent_event->hw.sample_period; | |
12446 | struct hw_perf_event *hwc = &child_event->hw; | |
12447 | ||
12448 | hwc->sample_period = sample_period; | |
12449 | hwc->last_period = sample_period; | |
12450 | ||
12451 | local64_set(&hwc->period_left, sample_period); | |
12452 | } | |
12453 | ||
12454 | child_event->ctx = child_ctx; | |
12455 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12456 | child_event->overflow_handler_context |
12457 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12458 | |
614b6780 TG |
12459 | /* |
12460 | * Precalculate sample_data sizes | |
12461 | */ | |
12462 | perf_event__header_size(child_event); | |
6844c09d | 12463 | perf_event__id_header_size(child_event); |
614b6780 | 12464 | |
97dee4f3 PZ |
12465 | /* |
12466 | * Link it up in the child's context: | |
12467 | */ | |
cee010ec | 12468 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12469 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12470 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12471 | |
97dee4f3 PZ |
12472 | /* |
12473 | * Link this into the parent event's child list | |
12474 | */ | |
97dee4f3 PZ |
12475 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12476 | mutex_unlock(&parent_event->child_mutex); | |
12477 | ||
12478 | return child_event; | |
12479 | } | |
12480 | ||
d8a8cfc7 PZ |
12481 | /* |
12482 | * Inherits an event group. | |
12483 | * | |
12484 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12485 | * This matches with perf_event_release_kernel() removing all child events. | |
12486 | * | |
12487 | * Returns: | |
12488 | * - 0 on success | |
12489 | * - <0 on error | |
12490 | */ | |
97dee4f3 PZ |
12491 | static int inherit_group(struct perf_event *parent_event, |
12492 | struct task_struct *parent, | |
12493 | struct perf_event_context *parent_ctx, | |
12494 | struct task_struct *child, | |
12495 | struct perf_event_context *child_ctx) | |
12496 | { | |
12497 | struct perf_event *leader; | |
12498 | struct perf_event *sub; | |
12499 | struct perf_event *child_ctr; | |
12500 | ||
12501 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12502 | child, NULL, child_ctx); | |
12503 | if (IS_ERR(leader)) | |
12504 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12505 | /* |
12506 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12507 | * case inherit_event() will create individual events, similar to what | |
12508 | * perf_group_detach() would do anyway. | |
12509 | */ | |
edb39592 | 12510 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12511 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12512 | child, leader, child_ctx); | |
12513 | if (IS_ERR(child_ctr)) | |
12514 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12515 | |
00496fe5 | 12516 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12517 | !perf_get_aux_event(child_ctr, leader)) |
12518 | return -EINVAL; | |
97dee4f3 PZ |
12519 | } |
12520 | return 0; | |
889ff015 FW |
12521 | } |
12522 | ||
d8a8cfc7 PZ |
12523 | /* |
12524 | * Creates the child task context and tries to inherit the event-group. | |
12525 | * | |
12526 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12527 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12528 | * consistent with perf_event_release_kernel() removing all child events. | |
12529 | * | |
12530 | * Returns: | |
12531 | * - 0 on success | |
12532 | * - <0 on error | |
12533 | */ | |
889ff015 FW |
12534 | static int |
12535 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12536 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12537 | struct task_struct *child, int ctxn, |
889ff015 FW |
12538 | int *inherited_all) |
12539 | { | |
12540 | int ret; | |
8dc85d54 | 12541 | struct perf_event_context *child_ctx; |
889ff015 FW |
12542 | |
12543 | if (!event->attr.inherit) { | |
12544 | *inherited_all = 0; | |
12545 | return 0; | |
bbbee908 PZ |
12546 | } |
12547 | ||
fe4b04fa | 12548 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12549 | if (!child_ctx) { |
12550 | /* | |
12551 | * This is executed from the parent task context, so | |
12552 | * inherit events that have been marked for cloning. | |
12553 | * First allocate and initialize a context for the | |
12554 | * child. | |
12555 | */ | |
734df5ab | 12556 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12557 | if (!child_ctx) |
12558 | return -ENOMEM; | |
bbbee908 | 12559 | |
8dc85d54 | 12560 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12561 | } |
12562 | ||
12563 | ret = inherit_group(event, parent, parent_ctx, | |
12564 | child, child_ctx); | |
12565 | ||
12566 | if (ret) | |
12567 | *inherited_all = 0; | |
12568 | ||
12569 | return ret; | |
bbbee908 PZ |
12570 | } |
12571 | ||
9b51f66d | 12572 | /* |
cdd6c482 | 12573 | * Initialize the perf_event context in task_struct |
9b51f66d | 12574 | */ |
985c8dcb | 12575 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12576 | { |
889ff015 | 12577 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12578 | struct perf_event_context *cloned_ctx; |
12579 | struct perf_event *event; | |
9b51f66d | 12580 | struct task_struct *parent = current; |
564c2b21 | 12581 | int inherited_all = 1; |
dddd3379 | 12582 | unsigned long flags; |
6ab423e0 | 12583 | int ret = 0; |
9b51f66d | 12584 | |
8dc85d54 | 12585 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12586 | return 0; |
12587 | ||
ad3a37de | 12588 | /* |
25346b93 PM |
12589 | * If the parent's context is a clone, pin it so it won't get |
12590 | * swapped under us. | |
ad3a37de | 12591 | */ |
8dc85d54 | 12592 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12593 | if (!parent_ctx) |
12594 | return 0; | |
25346b93 | 12595 | |
ad3a37de PM |
12596 | /* |
12597 | * No need to check if parent_ctx != NULL here; since we saw | |
12598 | * it non-NULL earlier, the only reason for it to become NULL | |
12599 | * is if we exit, and since we're currently in the middle of | |
12600 | * a fork we can't be exiting at the same time. | |
12601 | */ | |
ad3a37de | 12602 | |
9b51f66d IM |
12603 | /* |
12604 | * Lock the parent list. No need to lock the child - not PID | |
12605 | * hashed yet and not running, so nobody can access it. | |
12606 | */ | |
d859e29f | 12607 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12608 | |
12609 | /* | |
12610 | * We dont have to disable NMIs - we are only looking at | |
12611 | * the list, not manipulating it: | |
12612 | */ | |
6e6804d2 | 12613 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12614 | ret = inherit_task_group(event, parent, parent_ctx, |
12615 | child, ctxn, &inherited_all); | |
889ff015 | 12616 | if (ret) |
e7cc4865 | 12617 | goto out_unlock; |
889ff015 | 12618 | } |
b93f7978 | 12619 | |
dddd3379 TG |
12620 | /* |
12621 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12622 | * to allocations, but we need to prevent rotation because | |
12623 | * rotate_ctx() will change the list from interrupt context. | |
12624 | */ | |
12625 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12626 | parent_ctx->rotate_disable = 1; | |
12627 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12628 | ||
6e6804d2 | 12629 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12630 | ret = inherit_task_group(event, parent, parent_ctx, |
12631 | child, ctxn, &inherited_all); | |
889ff015 | 12632 | if (ret) |
e7cc4865 | 12633 | goto out_unlock; |
564c2b21 PM |
12634 | } |
12635 | ||
dddd3379 TG |
12636 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12637 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12638 | |
8dc85d54 | 12639 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12640 | |
05cbaa28 | 12641 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12642 | /* |
12643 | * Mark the child context as a clone of the parent | |
12644 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12645 | * |
12646 | * Note that if the parent is a clone, the holding of | |
12647 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12648 | */ |
c5ed5145 | 12649 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12650 | if (cloned_ctx) { |
12651 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12652 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12653 | } else { |
12654 | child_ctx->parent_ctx = parent_ctx; | |
12655 | child_ctx->parent_gen = parent_ctx->generation; | |
12656 | } | |
12657 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12658 | } |
12659 | ||
c5ed5145 | 12660 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12661 | out_unlock: |
d859e29f | 12662 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12663 | |
25346b93 | 12664 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12665 | put_ctx(parent_ctx); |
ad3a37de | 12666 | |
6ab423e0 | 12667 | return ret; |
9b51f66d IM |
12668 | } |
12669 | ||
8dc85d54 PZ |
12670 | /* |
12671 | * Initialize the perf_event context in task_struct | |
12672 | */ | |
12673 | int perf_event_init_task(struct task_struct *child) | |
12674 | { | |
12675 | int ctxn, ret; | |
12676 | ||
8550d7cb ON |
12677 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12678 | mutex_init(&child->perf_event_mutex); | |
12679 | INIT_LIST_HEAD(&child->perf_event_list); | |
12680 | ||
8dc85d54 PZ |
12681 | for_each_task_context_nr(ctxn) { |
12682 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12683 | if (ret) { |
12684 | perf_event_free_task(child); | |
8dc85d54 | 12685 | return ret; |
6c72e350 | 12686 | } |
8dc85d54 PZ |
12687 | } |
12688 | ||
12689 | return 0; | |
12690 | } | |
12691 | ||
220b140b PM |
12692 | static void __init perf_event_init_all_cpus(void) |
12693 | { | |
b28ab83c | 12694 | struct swevent_htable *swhash; |
220b140b | 12695 | int cpu; |
220b140b | 12696 | |
a63fbed7 TG |
12697 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12698 | ||
220b140b | 12699 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12700 | swhash = &per_cpu(swevent_htable, cpu); |
12701 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12702 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12703 | |
12704 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12705 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12706 | |
058fe1c0 DCC |
12707 | #ifdef CONFIG_CGROUP_PERF |
12708 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12709 | #endif | |
e48c1788 | 12710 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12711 | } |
12712 | } | |
12713 | ||
d18bf422 | 12714 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12715 | { |
108b02cf | 12716 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12717 | |
b28ab83c | 12718 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12719 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12720 | struct swevent_hlist *hlist; |
12721 | ||
b28ab83c PZ |
12722 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12723 | WARN_ON(!hlist); | |
12724 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12725 | } |
b28ab83c | 12726 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12727 | } |
12728 | ||
2965faa5 | 12729 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12730 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12731 | { |
108b02cf | 12732 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12733 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12734 | struct perf_event *event; | |
0793a61d | 12735 | |
fae3fde6 | 12736 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12737 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12738 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12739 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12740 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12741 | } |
108b02cf PZ |
12742 | |
12743 | static void perf_event_exit_cpu_context(int cpu) | |
12744 | { | |
a63fbed7 | 12745 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12746 | struct perf_event_context *ctx; |
12747 | struct pmu *pmu; | |
108b02cf | 12748 | |
a63fbed7 TG |
12749 | mutex_lock(&pmus_lock); |
12750 | list_for_each_entry(pmu, &pmus, entry) { | |
12751 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12752 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12753 | |
12754 | mutex_lock(&ctx->mutex); | |
12755 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12756 | cpuctx->online = 0; |
108b02cf PZ |
12757 | mutex_unlock(&ctx->mutex); |
12758 | } | |
a63fbed7 TG |
12759 | cpumask_clear_cpu(cpu, perf_online_mask); |
12760 | mutex_unlock(&pmus_lock); | |
108b02cf | 12761 | } |
00e16c3d TG |
12762 | #else |
12763 | ||
12764 | static void perf_event_exit_cpu_context(int cpu) { } | |
12765 | ||
12766 | #endif | |
108b02cf | 12767 | |
a63fbed7 TG |
12768 | int perf_event_init_cpu(unsigned int cpu) |
12769 | { | |
12770 | struct perf_cpu_context *cpuctx; | |
12771 | struct perf_event_context *ctx; | |
12772 | struct pmu *pmu; | |
12773 | ||
12774 | perf_swevent_init_cpu(cpu); | |
12775 | ||
12776 | mutex_lock(&pmus_lock); | |
12777 | cpumask_set_cpu(cpu, perf_online_mask); | |
12778 | list_for_each_entry(pmu, &pmus, entry) { | |
12779 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12780 | ctx = &cpuctx->ctx; | |
12781 | ||
12782 | mutex_lock(&ctx->mutex); | |
12783 | cpuctx->online = 1; | |
12784 | mutex_unlock(&ctx->mutex); | |
12785 | } | |
12786 | mutex_unlock(&pmus_lock); | |
12787 | ||
12788 | return 0; | |
12789 | } | |
12790 | ||
00e16c3d | 12791 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12792 | { |
e3703f8c | 12793 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12794 | return 0; |
0793a61d | 12795 | } |
0793a61d | 12796 | |
c277443c PZ |
12797 | static int |
12798 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12799 | { | |
12800 | int cpu; | |
12801 | ||
12802 | for_each_online_cpu(cpu) | |
12803 | perf_event_exit_cpu(cpu); | |
12804 | ||
12805 | return NOTIFY_OK; | |
12806 | } | |
12807 | ||
12808 | /* | |
12809 | * Run the perf reboot notifier at the very last possible moment so that | |
12810 | * the generic watchdog code runs as long as possible. | |
12811 | */ | |
12812 | static struct notifier_block perf_reboot_notifier = { | |
12813 | .notifier_call = perf_reboot, | |
12814 | .priority = INT_MIN, | |
12815 | }; | |
12816 | ||
cdd6c482 | 12817 | void __init perf_event_init(void) |
0793a61d | 12818 | { |
3c502e7a JW |
12819 | int ret; |
12820 | ||
2e80a82a PZ |
12821 | idr_init(&pmu_idr); |
12822 | ||
220b140b | 12823 | perf_event_init_all_cpus(); |
b0a873eb | 12824 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12825 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12826 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12827 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12828 | perf_tp_register(); |
00e16c3d | 12829 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12830 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12831 | |
12832 | ret = init_hw_breakpoint(); | |
12833 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12834 | |
b01c3a00 JO |
12835 | /* |
12836 | * Build time assertion that we keep the data_head at the intended | |
12837 | * location. IOW, validation we got the __reserved[] size right. | |
12838 | */ | |
12839 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12840 | != 1024); | |
0793a61d | 12841 | } |
abe43400 | 12842 | |
fd979c01 CS |
12843 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12844 | char *page) | |
12845 | { | |
12846 | struct perf_pmu_events_attr *pmu_attr = | |
12847 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12848 | ||
12849 | if (pmu_attr->event_str) | |
12850 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12851 | ||
12852 | return 0; | |
12853 | } | |
675965b0 | 12854 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12855 | |
abe43400 PZ |
12856 | static int __init perf_event_sysfs_init(void) |
12857 | { | |
12858 | struct pmu *pmu; | |
12859 | int ret; | |
12860 | ||
12861 | mutex_lock(&pmus_lock); | |
12862 | ||
12863 | ret = bus_register(&pmu_bus); | |
12864 | if (ret) | |
12865 | goto unlock; | |
12866 | ||
12867 | list_for_each_entry(pmu, &pmus, entry) { | |
12868 | if (!pmu->name || pmu->type < 0) | |
12869 | continue; | |
12870 | ||
12871 | ret = pmu_dev_alloc(pmu); | |
12872 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12873 | } | |
12874 | pmu_bus_running = 1; | |
12875 | ret = 0; | |
12876 | ||
12877 | unlock: | |
12878 | mutex_unlock(&pmus_lock); | |
12879 | ||
12880 | return ret; | |
12881 | } | |
12882 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12883 | |
12884 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12885 | static struct cgroup_subsys_state * |
12886 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12887 | { |
12888 | struct perf_cgroup *jc; | |
e5d1367f | 12889 | |
1b15d055 | 12890 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12891 | if (!jc) |
12892 | return ERR_PTR(-ENOMEM); | |
12893 | ||
e5d1367f SE |
12894 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12895 | if (!jc->info) { | |
12896 | kfree(jc); | |
12897 | return ERR_PTR(-ENOMEM); | |
12898 | } | |
12899 | ||
e5d1367f SE |
12900 | return &jc->css; |
12901 | } | |
12902 | ||
eb95419b | 12903 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12904 | { |
eb95419b TH |
12905 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12906 | ||
e5d1367f SE |
12907 | free_percpu(jc->info); |
12908 | kfree(jc); | |
12909 | } | |
12910 | ||
96aaab68 NK |
12911 | static int perf_cgroup_css_online(struct cgroup_subsys_state *css) |
12912 | { | |
12913 | perf_event_cgroup(css->cgroup); | |
12914 | return 0; | |
12915 | } | |
12916 | ||
e5d1367f SE |
12917 | static int __perf_cgroup_move(void *info) |
12918 | { | |
12919 | struct task_struct *task = info; | |
ddaaf4e2 | 12920 | rcu_read_lock(); |
e5d1367f | 12921 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12922 | rcu_read_unlock(); |
e5d1367f SE |
12923 | return 0; |
12924 | } | |
12925 | ||
1f7dd3e5 | 12926 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12927 | { |
bb9d97b6 | 12928 | struct task_struct *task; |
1f7dd3e5 | 12929 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12930 | |
1f7dd3e5 | 12931 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12932 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12933 | } |
12934 | ||
073219e9 | 12935 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12936 | .css_alloc = perf_cgroup_css_alloc, |
12937 | .css_free = perf_cgroup_css_free, | |
96aaab68 | 12938 | .css_online = perf_cgroup_css_online, |
bb9d97b6 | 12939 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12940 | /* |
12941 | * Implicitly enable on dfl hierarchy so that perf events can | |
12942 | * always be filtered by cgroup2 path as long as perf_event | |
12943 | * controller is not mounted on a legacy hierarchy. | |
12944 | */ | |
12945 | .implicit_on_dfl = true, | |
8cfd8147 | 12946 | .threaded = true, |
e5d1367f SE |
12947 | }; |
12948 | #endif /* CONFIG_CGROUP_PERF */ |