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Commit | Line | Data |
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8e86e015 | 1 | // SPDX-License-Identifier: GPL-2.0 |
0793a61d | 2 | /* |
57c0c15b | 3 | * Performance events core code: |
0793a61d | 4 | * |
98144511 | 5 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 7 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 8 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
0793a61d TG |
9 | */ |
10 | ||
11 | #include <linux/fs.h> | |
b9cacc7b | 12 | #include <linux/mm.h> |
0793a61d TG |
13 | #include <linux/cpu.h> |
14 | #include <linux/smp.h> | |
2e80a82a | 15 | #include <linux/idr.h> |
04289bb9 | 16 | #include <linux/file.h> |
0793a61d | 17 | #include <linux/poll.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
76e1d904 | 19 | #include <linux/hash.h> |
12351ef8 | 20 | #include <linux/tick.h> |
0793a61d | 21 | #include <linux/sysfs.h> |
22a4f650 | 22 | #include <linux/dcache.h> |
0793a61d | 23 | #include <linux/percpu.h> |
22a4f650 | 24 | #include <linux/ptrace.h> |
c277443c | 25 | #include <linux/reboot.h> |
b9cacc7b | 26 | #include <linux/vmstat.h> |
abe43400 | 27 | #include <linux/device.h> |
6e5fdeed | 28 | #include <linux/export.h> |
906010b2 | 29 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
30 | #include <linux/hardirq.h> |
31 | #include <linux/rculist.h> | |
0793a61d TG |
32 | #include <linux/uaccess.h> |
33 | #include <linux/syscalls.h> | |
34 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 35 | #include <linux/kernel_stat.h> |
39bed6cb | 36 | #include <linux/cgroup.h> |
cdd6c482 | 37 | #include <linux/perf_event.h> |
af658dca | 38 | #include <linux/trace_events.h> |
3c502e7a | 39 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 40 | #include <linux/mm_types.h> |
c464c76e | 41 | #include <linux/module.h> |
f972eb63 | 42 | #include <linux/mman.h> |
b3f20785 | 43 | #include <linux/compat.h> |
2541517c AS |
44 | #include <linux/bpf.h> |
45 | #include <linux/filter.h> | |
375637bc AS |
46 | #include <linux/namei.h> |
47 | #include <linux/parser.h> | |
e6017571 | 48 | #include <linux/sched/clock.h> |
6e84f315 | 49 | #include <linux/sched/mm.h> |
e4222673 HB |
50 | #include <linux/proc_ns.h> |
51 | #include <linux/mount.h> | |
0793a61d | 52 | |
76369139 FW |
53 | #include "internal.h" |
54 | ||
4e193bd4 TB |
55 | #include <asm/irq_regs.h> |
56 | ||
272325c4 PZ |
57 | typedef int (*remote_function_f)(void *); |
58 | ||
fe4b04fa | 59 | struct remote_function_call { |
e7e7ee2e | 60 | struct task_struct *p; |
272325c4 | 61 | remote_function_f func; |
e7e7ee2e IM |
62 | void *info; |
63 | int ret; | |
fe4b04fa PZ |
64 | }; |
65 | ||
66 | static void remote_function(void *data) | |
67 | { | |
68 | struct remote_function_call *tfc = data; | |
69 | struct task_struct *p = tfc->p; | |
70 | ||
71 | if (p) { | |
0da4cf3e PZ |
72 | /* -EAGAIN */ |
73 | if (task_cpu(p) != smp_processor_id()) | |
74 | return; | |
75 | ||
76 | /* | |
77 | * Now that we're on right CPU with IRQs disabled, we can test | |
78 | * if we hit the right task without races. | |
79 | */ | |
80 | ||
81 | tfc->ret = -ESRCH; /* No such (running) process */ | |
82 | if (p != current) | |
fe4b04fa PZ |
83 | return; |
84 | } | |
85 | ||
86 | tfc->ret = tfc->func(tfc->info); | |
87 | } | |
88 | ||
89 | /** | |
90 | * task_function_call - call a function on the cpu on which a task runs | |
91 | * @p: the task to evaluate | |
92 | * @func: the function to be called | |
93 | * @info: the function call argument | |
94 | * | |
95 | * Calls the function @func when the task is currently running. This might | |
96 | * be on the current CPU, which just calls the function directly | |
97 | * | |
98 | * returns: @func return value, or | |
99 | * -ESRCH - when the process isn't running | |
100 | * -EAGAIN - when the process moved away | |
101 | */ | |
102 | static int | |
272325c4 | 103 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
104 | { |
105 | struct remote_function_call data = { | |
e7e7ee2e IM |
106 | .p = p, |
107 | .func = func, | |
108 | .info = info, | |
0da4cf3e | 109 | .ret = -EAGAIN, |
fe4b04fa | 110 | }; |
0da4cf3e | 111 | int ret; |
fe4b04fa | 112 | |
0da4cf3e PZ |
113 | do { |
114 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
115 | if (!ret) | |
116 | ret = data.ret; | |
117 | } while (ret == -EAGAIN); | |
fe4b04fa | 118 | |
0da4cf3e | 119 | return ret; |
fe4b04fa PZ |
120 | } |
121 | ||
122 | /** | |
123 | * cpu_function_call - call a function on the cpu | |
124 | * @func: the function to be called | |
125 | * @info: the function call argument | |
126 | * | |
127 | * Calls the function @func on the remote cpu. | |
128 | * | |
129 | * returns: @func return value or -ENXIO when the cpu is offline | |
130 | */ | |
272325c4 | 131 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
132 | { |
133 | struct remote_function_call data = { | |
e7e7ee2e IM |
134 | .p = NULL, |
135 | .func = func, | |
136 | .info = info, | |
137 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
138 | }; |
139 | ||
140 | smp_call_function_single(cpu, remote_function, &data, 1); | |
141 | ||
142 | return data.ret; | |
143 | } | |
144 | ||
fae3fde6 PZ |
145 | static inline struct perf_cpu_context * |
146 | __get_cpu_context(struct perf_event_context *ctx) | |
147 | { | |
148 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
149 | } | |
150 | ||
151 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
152 | struct perf_event_context *ctx) | |
0017960f | 153 | { |
fae3fde6 PZ |
154 | raw_spin_lock(&cpuctx->ctx.lock); |
155 | if (ctx) | |
156 | raw_spin_lock(&ctx->lock); | |
157 | } | |
158 | ||
159 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
160 | struct perf_event_context *ctx) | |
161 | { | |
162 | if (ctx) | |
163 | raw_spin_unlock(&ctx->lock); | |
164 | raw_spin_unlock(&cpuctx->ctx.lock); | |
165 | } | |
166 | ||
63b6da39 PZ |
167 | #define TASK_TOMBSTONE ((void *)-1L) |
168 | ||
169 | static bool is_kernel_event(struct perf_event *event) | |
170 | { | |
f47c02c0 | 171 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
172 | } |
173 | ||
39a43640 PZ |
174 | /* |
175 | * On task ctx scheduling... | |
176 | * | |
177 | * When !ctx->nr_events a task context will not be scheduled. This means | |
178 | * we can disable the scheduler hooks (for performance) without leaving | |
179 | * pending task ctx state. | |
180 | * | |
181 | * This however results in two special cases: | |
182 | * | |
183 | * - removing the last event from a task ctx; this is relatively straight | |
184 | * forward and is done in __perf_remove_from_context. | |
185 | * | |
186 | * - adding the first event to a task ctx; this is tricky because we cannot | |
187 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
188 | * See perf_install_in_context(). | |
189 | * | |
39a43640 PZ |
190 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
191 | */ | |
192 | ||
fae3fde6 PZ |
193 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
194 | struct perf_event_context *, void *); | |
195 | ||
196 | struct event_function_struct { | |
197 | struct perf_event *event; | |
198 | event_f func; | |
199 | void *data; | |
200 | }; | |
201 | ||
202 | static int event_function(void *info) | |
203 | { | |
204 | struct event_function_struct *efs = info; | |
205 | struct perf_event *event = efs->event; | |
0017960f | 206 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
207 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
208 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 209 | int ret = 0; |
fae3fde6 | 210 | |
16444645 | 211 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 212 | |
63b6da39 | 213 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
214 | /* |
215 | * Since we do the IPI call without holding ctx->lock things can have | |
216 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
217 | */ |
218 | if (ctx->task) { | |
63b6da39 | 219 | if (ctx->task != current) { |
0da4cf3e | 220 | ret = -ESRCH; |
63b6da39 PZ |
221 | goto unlock; |
222 | } | |
fae3fde6 | 223 | |
fae3fde6 PZ |
224 | /* |
225 | * We only use event_function_call() on established contexts, | |
226 | * and event_function() is only ever called when active (or | |
227 | * rather, we'll have bailed in task_function_call() or the | |
228 | * above ctx->task != current test), therefore we must have | |
229 | * ctx->is_active here. | |
230 | */ | |
231 | WARN_ON_ONCE(!ctx->is_active); | |
232 | /* | |
233 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
234 | * match. | |
235 | */ | |
63b6da39 PZ |
236 | WARN_ON_ONCE(task_ctx != ctx); |
237 | } else { | |
238 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 239 | } |
63b6da39 | 240 | |
fae3fde6 | 241 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 242 | unlock: |
fae3fde6 PZ |
243 | perf_ctx_unlock(cpuctx, task_ctx); |
244 | ||
63b6da39 | 245 | return ret; |
fae3fde6 PZ |
246 | } |
247 | ||
fae3fde6 | 248 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
249 | { |
250 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 251 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
252 | struct event_function_struct efs = { |
253 | .event = event, | |
254 | .func = func, | |
255 | .data = data, | |
256 | }; | |
0017960f | 257 | |
c97f4736 PZ |
258 | if (!event->parent) { |
259 | /* | |
260 | * If this is a !child event, we must hold ctx::mutex to | |
261 | * stabilize the the event->ctx relation. See | |
262 | * perf_event_ctx_lock(). | |
263 | */ | |
264 | lockdep_assert_held(&ctx->mutex); | |
265 | } | |
0017960f PZ |
266 | |
267 | if (!task) { | |
fae3fde6 | 268 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
269 | return; |
270 | } | |
271 | ||
63b6da39 PZ |
272 | if (task == TASK_TOMBSTONE) |
273 | return; | |
274 | ||
a096309b | 275 | again: |
fae3fde6 | 276 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
277 | return; |
278 | ||
279 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
280 | /* |
281 | * Reload the task pointer, it might have been changed by | |
282 | * a concurrent perf_event_context_sched_out(). | |
283 | */ | |
284 | task = ctx->task; | |
a096309b PZ |
285 | if (task == TASK_TOMBSTONE) { |
286 | raw_spin_unlock_irq(&ctx->lock); | |
287 | return; | |
0017960f | 288 | } |
a096309b PZ |
289 | if (ctx->is_active) { |
290 | raw_spin_unlock_irq(&ctx->lock); | |
291 | goto again; | |
292 | } | |
293 | func(event, NULL, ctx, data); | |
0017960f PZ |
294 | raw_spin_unlock_irq(&ctx->lock); |
295 | } | |
296 | ||
cca20946 PZ |
297 | /* |
298 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
299 | * are already disabled and we're on the right CPU. | |
300 | */ | |
301 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
302 | { | |
303 | struct perf_event_context *ctx = event->ctx; | |
304 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
305 | struct task_struct *task = READ_ONCE(ctx->task); | |
306 | struct perf_event_context *task_ctx = NULL; | |
307 | ||
16444645 | 308 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
309 | |
310 | if (task) { | |
311 | if (task == TASK_TOMBSTONE) | |
312 | return; | |
313 | ||
314 | task_ctx = ctx; | |
315 | } | |
316 | ||
317 | perf_ctx_lock(cpuctx, task_ctx); | |
318 | ||
319 | task = ctx->task; | |
320 | if (task == TASK_TOMBSTONE) | |
321 | goto unlock; | |
322 | ||
323 | if (task) { | |
324 | /* | |
325 | * We must be either inactive or active and the right task, | |
326 | * otherwise we're screwed, since we cannot IPI to somewhere | |
327 | * else. | |
328 | */ | |
329 | if (ctx->is_active) { | |
330 | if (WARN_ON_ONCE(task != current)) | |
331 | goto unlock; | |
332 | ||
333 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
334 | goto unlock; | |
335 | } | |
336 | } else { | |
337 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
338 | } | |
339 | ||
340 | func(event, cpuctx, ctx, data); | |
341 | unlock: | |
342 | perf_ctx_unlock(cpuctx, task_ctx); | |
343 | } | |
344 | ||
e5d1367f SE |
345 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
346 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
347 | PERF_FLAG_PID_CGROUP |\ |
348 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 349 | |
bce38cd5 SE |
350 | /* |
351 | * branch priv levels that need permission checks | |
352 | */ | |
353 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
354 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
355 | PERF_SAMPLE_BRANCH_HV) | |
356 | ||
0b3fcf17 SE |
357 | enum event_type_t { |
358 | EVENT_FLEXIBLE = 0x1, | |
359 | EVENT_PINNED = 0x2, | |
3cbaa590 | 360 | EVENT_TIME = 0x4, |
487f05e1 AS |
361 | /* see ctx_resched() for details */ |
362 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
363 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
364 | }; | |
365 | ||
e5d1367f SE |
366 | /* |
367 | * perf_sched_events : >0 events exist | |
368 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
369 | */ | |
9107c89e PZ |
370 | |
371 | static void perf_sched_delayed(struct work_struct *work); | |
372 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
373 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
374 | static DEFINE_MUTEX(perf_sched_mutex); | |
375 | static atomic_t perf_sched_count; | |
376 | ||
e5d1367f | 377 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 378 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 379 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 380 | |
cdd6c482 IM |
381 | static atomic_t nr_mmap_events __read_mostly; |
382 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 383 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 384 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 385 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 386 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 387 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 388 | static atomic_t nr_bpf_events __read_mostly; |
9ee318a7 | 389 | |
108b02cf PZ |
390 | static LIST_HEAD(pmus); |
391 | static DEFINE_MUTEX(pmus_lock); | |
392 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 393 | static cpumask_var_t perf_online_mask; |
108b02cf | 394 | |
0764771d | 395 | /* |
cdd6c482 | 396 | * perf event paranoia level: |
0fbdea19 IM |
397 | * -1 - not paranoid at all |
398 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 399 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 400 | * 2 - disallow kernel profiling for unpriv |
0764771d | 401 | */ |
0161028b | 402 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 403 | |
20443384 FW |
404 | /* Minimum for 512 kiB + 1 user control page */ |
405 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
406 | |
407 | /* | |
cdd6c482 | 408 | * max perf event sample rate |
df58ab24 | 409 | */ |
14c63f17 DH |
410 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
411 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
412 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
413 | ||
414 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
415 | ||
416 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
417 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
418 | ||
d9494cb4 PZ |
419 | static int perf_sample_allowed_ns __read_mostly = |
420 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 421 | |
18ab2cd3 | 422 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
423 | { |
424 | u64 tmp = perf_sample_period_ns; | |
425 | ||
426 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
427 | tmp = div_u64(tmp, 100); |
428 | if (!tmp) | |
429 | tmp = 1; | |
430 | ||
431 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 432 | } |
163ec435 | 433 | |
8d5bce0c | 434 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 435 | |
163ec435 PZ |
436 | int perf_proc_update_handler(struct ctl_table *table, int write, |
437 | void __user *buffer, size_t *lenp, | |
438 | loff_t *ppos) | |
439 | { | |
1a51c5da SE |
440 | int ret; |
441 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
442 | /* |
443 | * If throttling is disabled don't allow the write: | |
444 | */ | |
1a51c5da | 445 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
446 | return -EINVAL; |
447 | ||
1a51c5da SE |
448 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
449 | if (ret || !write) | |
450 | return ret; | |
451 | ||
163ec435 | 452 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
453 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
454 | update_perf_cpu_limits(); | |
455 | ||
456 | return 0; | |
457 | } | |
458 | ||
459 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
460 | ||
461 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
462 | void __user *buffer, size_t *lenp, | |
463 | loff_t *ppos) | |
464 | { | |
1572e45a | 465 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
466 | |
467 | if (ret || !write) | |
468 | return ret; | |
469 | ||
b303e7c1 PZ |
470 | if (sysctl_perf_cpu_time_max_percent == 100 || |
471 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
472 | printk(KERN_WARNING |
473 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
474 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
475 | } else { | |
476 | update_perf_cpu_limits(); | |
477 | } | |
163ec435 PZ |
478 | |
479 | return 0; | |
480 | } | |
1ccd1549 | 481 | |
14c63f17 DH |
482 | /* |
483 | * perf samples are done in some very critical code paths (NMIs). | |
484 | * If they take too much CPU time, the system can lock up and not | |
485 | * get any real work done. This will drop the sample rate when | |
486 | * we detect that events are taking too long. | |
487 | */ | |
488 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 489 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 490 | |
91a612ee PZ |
491 | static u64 __report_avg; |
492 | static u64 __report_allowed; | |
493 | ||
6a02ad66 | 494 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 495 | { |
0d87d7ec | 496 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
497 | "perf: interrupt took too long (%lld > %lld), lowering " |
498 | "kernel.perf_event_max_sample_rate to %d\n", | |
499 | __report_avg, __report_allowed, | |
500 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
501 | } |
502 | ||
503 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
504 | ||
505 | void perf_sample_event_took(u64 sample_len_ns) | |
506 | { | |
91a612ee PZ |
507 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
508 | u64 running_len; | |
509 | u64 avg_len; | |
510 | u32 max; | |
14c63f17 | 511 | |
91a612ee | 512 | if (max_len == 0) |
14c63f17 DH |
513 | return; |
514 | ||
91a612ee PZ |
515 | /* Decay the counter by 1 average sample. */ |
516 | running_len = __this_cpu_read(running_sample_length); | |
517 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
518 | running_len += sample_len_ns; | |
519 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
520 | |
521 | /* | |
91a612ee PZ |
522 | * Note: this will be biased artifically low until we have |
523 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
524 | * from having to maintain a count. |
525 | */ | |
91a612ee PZ |
526 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
527 | if (avg_len <= max_len) | |
14c63f17 DH |
528 | return; |
529 | ||
91a612ee PZ |
530 | __report_avg = avg_len; |
531 | __report_allowed = max_len; | |
14c63f17 | 532 | |
91a612ee PZ |
533 | /* |
534 | * Compute a throttle threshold 25% below the current duration. | |
535 | */ | |
536 | avg_len += avg_len / 4; | |
537 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
538 | if (avg_len < max) | |
539 | max /= (u32)avg_len; | |
540 | else | |
541 | max = 1; | |
14c63f17 | 542 | |
91a612ee PZ |
543 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
544 | WRITE_ONCE(max_samples_per_tick, max); | |
545 | ||
546 | sysctl_perf_event_sample_rate = max * HZ; | |
547 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 548 | |
cd578abb | 549 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 550 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 551 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 552 | __report_avg, __report_allowed, |
cd578abb PZ |
553 | sysctl_perf_event_sample_rate); |
554 | } | |
14c63f17 DH |
555 | } |
556 | ||
cdd6c482 | 557 | static atomic64_t perf_event_id; |
a96bbc16 | 558 | |
0b3fcf17 SE |
559 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
560 | enum event_type_t event_type); | |
561 | ||
562 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
563 | enum event_type_t event_type, |
564 | struct task_struct *task); | |
565 | ||
566 | static void update_context_time(struct perf_event_context *ctx); | |
567 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 568 | |
cdd6c482 | 569 | void __weak perf_event_print_debug(void) { } |
0793a61d | 570 | |
84c79910 | 571 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 572 | { |
84c79910 | 573 | return "pmu"; |
0793a61d TG |
574 | } |
575 | ||
0b3fcf17 SE |
576 | static inline u64 perf_clock(void) |
577 | { | |
578 | return local_clock(); | |
579 | } | |
580 | ||
34f43927 PZ |
581 | static inline u64 perf_event_clock(struct perf_event *event) |
582 | { | |
583 | return event->clock(); | |
584 | } | |
585 | ||
0d3d73aa PZ |
586 | /* |
587 | * State based event timekeeping... | |
588 | * | |
589 | * The basic idea is to use event->state to determine which (if any) time | |
590 | * fields to increment with the current delta. This means we only need to | |
591 | * update timestamps when we change state or when they are explicitly requested | |
592 | * (read). | |
593 | * | |
594 | * Event groups make things a little more complicated, but not terribly so. The | |
595 | * rules for a group are that if the group leader is OFF the entire group is | |
596 | * OFF, irrespecive of what the group member states are. This results in | |
597 | * __perf_effective_state(). | |
598 | * | |
599 | * A futher ramification is that when a group leader flips between OFF and | |
600 | * !OFF, we need to update all group member times. | |
601 | * | |
602 | * | |
603 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
604 | * need to make sure the relevant context time is updated before we try and | |
605 | * update our timestamps. | |
606 | */ | |
607 | ||
608 | static __always_inline enum perf_event_state | |
609 | __perf_effective_state(struct perf_event *event) | |
610 | { | |
611 | struct perf_event *leader = event->group_leader; | |
612 | ||
613 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
614 | return leader->state; | |
615 | ||
616 | return event->state; | |
617 | } | |
618 | ||
619 | static __always_inline void | |
620 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
621 | { | |
622 | enum perf_event_state state = __perf_effective_state(event); | |
623 | u64 delta = now - event->tstamp; | |
624 | ||
625 | *enabled = event->total_time_enabled; | |
626 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
627 | *enabled += delta; | |
628 | ||
629 | *running = event->total_time_running; | |
630 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
631 | *running += delta; | |
632 | } | |
633 | ||
634 | static void perf_event_update_time(struct perf_event *event) | |
635 | { | |
636 | u64 now = perf_event_time(event); | |
637 | ||
638 | __perf_update_times(event, now, &event->total_time_enabled, | |
639 | &event->total_time_running); | |
640 | event->tstamp = now; | |
641 | } | |
642 | ||
643 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
644 | { | |
645 | struct perf_event *sibling; | |
646 | ||
edb39592 | 647 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
648 | perf_event_update_time(sibling); |
649 | } | |
650 | ||
651 | static void | |
652 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
653 | { | |
654 | if (event->state == state) | |
655 | return; | |
656 | ||
657 | perf_event_update_time(event); | |
658 | /* | |
659 | * If a group leader gets enabled/disabled all its siblings | |
660 | * are affected too. | |
661 | */ | |
662 | if ((event->state < 0) ^ (state < 0)) | |
663 | perf_event_update_sibling_time(event); | |
664 | ||
665 | WRITE_ONCE(event->state, state); | |
666 | } | |
667 | ||
e5d1367f SE |
668 | #ifdef CONFIG_CGROUP_PERF |
669 | ||
e5d1367f SE |
670 | static inline bool |
671 | perf_cgroup_match(struct perf_event *event) | |
672 | { | |
673 | struct perf_event_context *ctx = event->ctx; | |
674 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
675 | ||
ef824fa1 TH |
676 | /* @event doesn't care about cgroup */ |
677 | if (!event->cgrp) | |
678 | return true; | |
679 | ||
680 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
681 | if (!cpuctx->cgrp) | |
682 | return false; | |
683 | ||
684 | /* | |
685 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
686 | * also enabled for all its descendant cgroups. If @cpuctx's | |
687 | * cgroup is a descendant of @event's (the test covers identity | |
688 | * case), it's a match. | |
689 | */ | |
690 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
691 | event->cgrp->css.cgroup); | |
e5d1367f SE |
692 | } |
693 | ||
e5d1367f SE |
694 | static inline void perf_detach_cgroup(struct perf_event *event) |
695 | { | |
4e2ba650 | 696 | css_put(&event->cgrp->css); |
e5d1367f SE |
697 | event->cgrp = NULL; |
698 | } | |
699 | ||
700 | static inline int is_cgroup_event(struct perf_event *event) | |
701 | { | |
702 | return event->cgrp != NULL; | |
703 | } | |
704 | ||
705 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
706 | { | |
707 | struct perf_cgroup_info *t; | |
708 | ||
709 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
710 | return t->time; | |
711 | } | |
712 | ||
713 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
714 | { | |
715 | struct perf_cgroup_info *info; | |
716 | u64 now; | |
717 | ||
718 | now = perf_clock(); | |
719 | ||
720 | info = this_cpu_ptr(cgrp->info); | |
721 | ||
722 | info->time += now - info->timestamp; | |
723 | info->timestamp = now; | |
724 | } | |
725 | ||
726 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
727 | { | |
c917e0f2 SL |
728 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
729 | struct cgroup_subsys_state *css; | |
730 | ||
731 | if (cgrp) { | |
732 | for (css = &cgrp->css; css; css = css->parent) { | |
733 | cgrp = container_of(css, struct perf_cgroup, css); | |
734 | __update_cgrp_time(cgrp); | |
735 | } | |
736 | } | |
e5d1367f SE |
737 | } |
738 | ||
739 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
740 | { | |
3f7cce3c SE |
741 | struct perf_cgroup *cgrp; |
742 | ||
e5d1367f | 743 | /* |
3f7cce3c SE |
744 | * ensure we access cgroup data only when needed and |
745 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 746 | */ |
3f7cce3c | 747 | if (!is_cgroup_event(event)) |
e5d1367f SE |
748 | return; |
749 | ||
614e4c4e | 750 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
751 | /* |
752 | * Do not update time when cgroup is not active | |
753 | */ | |
28fa741c | 754 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 755 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
756 | } |
757 | ||
758 | static inline void | |
3f7cce3c SE |
759 | perf_cgroup_set_timestamp(struct task_struct *task, |
760 | struct perf_event_context *ctx) | |
e5d1367f SE |
761 | { |
762 | struct perf_cgroup *cgrp; | |
763 | struct perf_cgroup_info *info; | |
c917e0f2 | 764 | struct cgroup_subsys_state *css; |
e5d1367f | 765 | |
3f7cce3c SE |
766 | /* |
767 | * ctx->lock held by caller | |
768 | * ensure we do not access cgroup data | |
769 | * unless we have the cgroup pinned (css_get) | |
770 | */ | |
771 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
772 | return; |
773 | ||
614e4c4e | 774 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
775 | |
776 | for (css = &cgrp->css; css; css = css->parent) { | |
777 | cgrp = container_of(css, struct perf_cgroup, css); | |
778 | info = this_cpu_ptr(cgrp->info); | |
779 | info->timestamp = ctx->timestamp; | |
780 | } | |
e5d1367f SE |
781 | } |
782 | ||
058fe1c0 DCC |
783 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
784 | ||
e5d1367f SE |
785 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
786 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
787 | ||
788 | /* | |
789 | * reschedule events based on the cgroup constraint of task. | |
790 | * | |
791 | * mode SWOUT : schedule out everything | |
792 | * mode SWIN : schedule in based on cgroup for next | |
793 | */ | |
18ab2cd3 | 794 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
795 | { |
796 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 797 | struct list_head *list; |
e5d1367f SE |
798 | unsigned long flags; |
799 | ||
800 | /* | |
058fe1c0 DCC |
801 | * Disable interrupts and preemption to avoid this CPU's |
802 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
803 | */ |
804 | local_irq_save(flags); | |
805 | ||
058fe1c0 DCC |
806 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
807 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
808 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 809 | |
058fe1c0 DCC |
810 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
811 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 812 | |
058fe1c0 DCC |
813 | if (mode & PERF_CGROUP_SWOUT) { |
814 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
815 | /* | |
816 | * must not be done before ctxswout due | |
817 | * to event_filter_match() in event_sched_out() | |
818 | */ | |
819 | cpuctx->cgrp = NULL; | |
820 | } | |
e5d1367f | 821 | |
058fe1c0 DCC |
822 | if (mode & PERF_CGROUP_SWIN) { |
823 | WARN_ON_ONCE(cpuctx->cgrp); | |
824 | /* | |
825 | * set cgrp before ctxsw in to allow | |
826 | * event_filter_match() to not have to pass | |
827 | * task around | |
828 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
829 | * because cgorup events are only per-cpu | |
830 | */ | |
831 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
832 | &cpuctx->ctx); | |
833 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 834 | } |
058fe1c0 DCC |
835 | perf_pmu_enable(cpuctx->ctx.pmu); |
836 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
837 | } |
838 | ||
e5d1367f SE |
839 | local_irq_restore(flags); |
840 | } | |
841 | ||
a8d757ef SE |
842 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
843 | struct task_struct *next) | |
e5d1367f | 844 | { |
a8d757ef SE |
845 | struct perf_cgroup *cgrp1; |
846 | struct perf_cgroup *cgrp2 = NULL; | |
847 | ||
ddaaf4e2 | 848 | rcu_read_lock(); |
a8d757ef SE |
849 | /* |
850 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
851 | * we do not need to pass the ctx here because we know |
852 | * we are holding the rcu lock | |
a8d757ef | 853 | */ |
614e4c4e | 854 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 855 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
856 | |
857 | /* | |
858 | * only schedule out current cgroup events if we know | |
859 | * that we are switching to a different cgroup. Otherwise, | |
860 | * do no touch the cgroup events. | |
861 | */ | |
862 | if (cgrp1 != cgrp2) | |
863 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
864 | |
865 | rcu_read_unlock(); | |
e5d1367f SE |
866 | } |
867 | ||
a8d757ef SE |
868 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
869 | struct task_struct *task) | |
e5d1367f | 870 | { |
a8d757ef SE |
871 | struct perf_cgroup *cgrp1; |
872 | struct perf_cgroup *cgrp2 = NULL; | |
873 | ||
ddaaf4e2 | 874 | rcu_read_lock(); |
a8d757ef SE |
875 | /* |
876 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
877 | * we do not need to pass the ctx here because we know |
878 | * we are holding the rcu lock | |
a8d757ef | 879 | */ |
614e4c4e | 880 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 881 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
882 | |
883 | /* | |
884 | * only need to schedule in cgroup events if we are changing | |
885 | * cgroup during ctxsw. Cgroup events were not scheduled | |
886 | * out of ctxsw out if that was not the case. | |
887 | */ | |
888 | if (cgrp1 != cgrp2) | |
889 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
890 | |
891 | rcu_read_unlock(); | |
e5d1367f SE |
892 | } |
893 | ||
894 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
895 | struct perf_event_attr *attr, | |
896 | struct perf_event *group_leader) | |
897 | { | |
898 | struct perf_cgroup *cgrp; | |
899 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
900 | struct fd f = fdget(fd); |
901 | int ret = 0; | |
e5d1367f | 902 | |
2903ff01 | 903 | if (!f.file) |
e5d1367f SE |
904 | return -EBADF; |
905 | ||
b583043e | 906 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 907 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
908 | if (IS_ERR(css)) { |
909 | ret = PTR_ERR(css); | |
910 | goto out; | |
911 | } | |
e5d1367f SE |
912 | |
913 | cgrp = container_of(css, struct perf_cgroup, css); | |
914 | event->cgrp = cgrp; | |
915 | ||
916 | /* | |
917 | * all events in a group must monitor | |
918 | * the same cgroup because a task belongs | |
919 | * to only one perf cgroup at a time | |
920 | */ | |
921 | if (group_leader && group_leader->cgrp != cgrp) { | |
922 | perf_detach_cgroup(event); | |
923 | ret = -EINVAL; | |
e5d1367f | 924 | } |
3db272c0 | 925 | out: |
2903ff01 | 926 | fdput(f); |
e5d1367f SE |
927 | return ret; |
928 | } | |
929 | ||
930 | static inline void | |
931 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
932 | { | |
933 | struct perf_cgroup_info *t; | |
934 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
935 | event->shadow_ctx_time = now - t->timestamp; | |
936 | } | |
937 | ||
db4a8356 DCC |
938 | /* |
939 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
940 | * cleared when last cgroup event is removed. | |
941 | */ | |
942 | static inline void | |
943 | list_update_cgroup_event(struct perf_event *event, | |
944 | struct perf_event_context *ctx, bool add) | |
945 | { | |
946 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 947 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
948 | |
949 | if (!is_cgroup_event(event)) | |
950 | return; | |
951 | ||
db4a8356 DCC |
952 | /* |
953 | * Because cgroup events are always per-cpu events, | |
954 | * this will always be called from the right CPU. | |
955 | */ | |
956 | cpuctx = __get_cpu_context(ctx); | |
33801b94 | 957 | |
958 | /* | |
959 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
960 | * matching the event's cgroup, we must do this for every new event, | |
961 | * because if the first would mismatch, the second would not try again | |
962 | * and we would leave cpuctx->cgrp unset. | |
963 | */ | |
964 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
965 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
966 | ||
be96b316 TH |
967 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
968 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 969 | } |
33801b94 | 970 | |
971 | if (add && ctx->nr_cgroups++) | |
972 | return; | |
973 | else if (!add && --ctx->nr_cgroups) | |
974 | return; | |
975 | ||
976 | /* no cgroup running */ | |
977 | if (!add) | |
978 | cpuctx->cgrp = NULL; | |
979 | ||
980 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
981 | if (add) | |
982 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
983 | else | |
984 | list_del(cpuctx_entry); | |
db4a8356 DCC |
985 | } |
986 | ||
e5d1367f SE |
987 | #else /* !CONFIG_CGROUP_PERF */ |
988 | ||
989 | static inline bool | |
990 | perf_cgroup_match(struct perf_event *event) | |
991 | { | |
992 | return true; | |
993 | } | |
994 | ||
995 | static inline void perf_detach_cgroup(struct perf_event *event) | |
996 | {} | |
997 | ||
998 | static inline int is_cgroup_event(struct perf_event *event) | |
999 | { | |
1000 | return 0; | |
1001 | } | |
1002 | ||
e5d1367f SE |
1003 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1004 | { | |
1005 | } | |
1006 | ||
1007 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1008 | { | |
1009 | } | |
1010 | ||
a8d757ef SE |
1011 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1012 | struct task_struct *next) | |
e5d1367f SE |
1013 | { |
1014 | } | |
1015 | ||
a8d757ef SE |
1016 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1017 | struct task_struct *task) | |
e5d1367f SE |
1018 | { |
1019 | } | |
1020 | ||
1021 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1022 | struct perf_event_attr *attr, | |
1023 | struct perf_event *group_leader) | |
1024 | { | |
1025 | return -EINVAL; | |
1026 | } | |
1027 | ||
1028 | static inline void | |
3f7cce3c SE |
1029 | perf_cgroup_set_timestamp(struct task_struct *task, |
1030 | struct perf_event_context *ctx) | |
e5d1367f SE |
1031 | { |
1032 | } | |
1033 | ||
1034 | void | |
1035 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
1036 | { | |
1037 | } | |
1038 | ||
1039 | static inline void | |
1040 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1041 | { | |
1042 | } | |
1043 | ||
1044 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1045 | { | |
1046 | return 0; | |
1047 | } | |
1048 | ||
db4a8356 DCC |
1049 | static inline void |
1050 | list_update_cgroup_event(struct perf_event *event, | |
1051 | struct perf_event_context *ctx, bool add) | |
1052 | { | |
1053 | } | |
1054 | ||
e5d1367f SE |
1055 | #endif |
1056 | ||
9e630205 SE |
1057 | /* |
1058 | * set default to be dependent on timer tick just | |
1059 | * like original code | |
1060 | */ | |
1061 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1062 | /* | |
8a1115ff | 1063 | * function must be called with interrupts disabled |
9e630205 | 1064 | */ |
272325c4 | 1065 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1066 | { |
1067 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1068 | bool rotations; |
9e630205 | 1069 | |
16444645 | 1070 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1071 | |
1072 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1073 | rotations = perf_rotate_context(cpuctx); |
1074 | ||
4cfafd30 PZ |
1075 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1076 | if (rotations) | |
9e630205 | 1077 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1078 | else |
1079 | cpuctx->hrtimer_active = 0; | |
1080 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1081 | |
4cfafd30 | 1082 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1083 | } |
1084 | ||
272325c4 | 1085 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1086 | { |
272325c4 | 1087 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1088 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1089 | u64 interval; |
9e630205 SE |
1090 | |
1091 | /* no multiplexing needed for SW PMU */ | |
1092 | if (pmu->task_ctx_nr == perf_sw_context) | |
1093 | return; | |
1094 | ||
62b85639 SE |
1095 | /* |
1096 | * check default is sane, if not set then force to | |
1097 | * default interval (1/tick) | |
1098 | */ | |
272325c4 PZ |
1099 | interval = pmu->hrtimer_interval_ms; |
1100 | if (interval < 1) | |
1101 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1102 | |
272325c4 | 1103 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1104 | |
4cfafd30 PZ |
1105 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1106 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1107 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1108 | } |
1109 | ||
272325c4 | 1110 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1111 | { |
272325c4 | 1112 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1113 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1114 | unsigned long flags; |
9e630205 SE |
1115 | |
1116 | /* not for SW PMU */ | |
1117 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1118 | return 0; |
9e630205 | 1119 | |
4cfafd30 PZ |
1120 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1121 | if (!cpuctx->hrtimer_active) { | |
1122 | cpuctx->hrtimer_active = 1; | |
1123 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1124 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1125 | } | |
1126 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1127 | |
272325c4 | 1128 | return 0; |
9e630205 SE |
1129 | } |
1130 | ||
33696fc0 | 1131 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1132 | { |
33696fc0 PZ |
1133 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1134 | if (!(*count)++) | |
1135 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1136 | } |
9e35ad38 | 1137 | |
33696fc0 | 1138 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1139 | { |
33696fc0 PZ |
1140 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1141 | if (!--(*count)) | |
1142 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1143 | } |
9e35ad38 | 1144 | |
2fde4f94 | 1145 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1146 | |
1147 | /* | |
2fde4f94 MR |
1148 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1149 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1150 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1151 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1152 | */ |
2fde4f94 | 1153 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1154 | { |
2fde4f94 | 1155 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1156 | |
16444645 | 1157 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1158 | |
2fde4f94 MR |
1159 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1160 | ||
1161 | list_add(&ctx->active_ctx_list, head); | |
1162 | } | |
1163 | ||
1164 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1165 | { | |
16444645 | 1166 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1167 | |
1168 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1169 | ||
1170 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1171 | } |
9e35ad38 | 1172 | |
cdd6c482 | 1173 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1174 | { |
e5289d4a | 1175 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1176 | } |
1177 | ||
4af57ef2 YZ |
1178 | static void free_ctx(struct rcu_head *head) |
1179 | { | |
1180 | struct perf_event_context *ctx; | |
1181 | ||
1182 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1183 | kfree(ctx->task_ctx_data); | |
1184 | kfree(ctx); | |
1185 | } | |
1186 | ||
cdd6c482 | 1187 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1188 | { |
564c2b21 PM |
1189 | if (atomic_dec_and_test(&ctx->refcount)) { |
1190 | if (ctx->parent_ctx) | |
1191 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1192 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1193 | put_task_struct(ctx->task); |
4af57ef2 | 1194 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1195 | } |
a63eaf34 PM |
1196 | } |
1197 | ||
f63a8daa PZ |
1198 | /* |
1199 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1200 | * perf_pmu_migrate_context() we need some magic. | |
1201 | * | |
1202 | * Those places that change perf_event::ctx will hold both | |
1203 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1204 | * | |
8b10c5e2 PZ |
1205 | * Lock ordering is by mutex address. There are two other sites where |
1206 | * perf_event_context::mutex nests and those are: | |
1207 | * | |
1208 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1209 | * perf_event_exit_event() |
1210 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1211 | * |
1212 | * - perf_event_init_context() [ parent, 0 ] | |
1213 | * inherit_task_group() | |
1214 | * inherit_group() | |
1215 | * inherit_event() | |
1216 | * perf_event_alloc() | |
1217 | * perf_init_event() | |
1218 | * perf_try_init_event() [ child , 1 ] | |
1219 | * | |
1220 | * While it appears there is an obvious deadlock here -- the parent and child | |
1221 | * nesting levels are inverted between the two. This is in fact safe because | |
1222 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1223 | * spawning task cannot (yet) exit. | |
1224 | * | |
1225 | * But remember that that these are parent<->child context relations, and | |
1226 | * migration does not affect children, therefore these two orderings should not | |
1227 | * interact. | |
f63a8daa PZ |
1228 | * |
1229 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1230 | * because the sys_perf_event_open() case will install a new event and break | |
1231 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1232 | * concerned with cpuctx and that doesn't have children. | |
1233 | * | |
1234 | * The places that change perf_event::ctx will issue: | |
1235 | * | |
1236 | * perf_remove_from_context(); | |
1237 | * synchronize_rcu(); | |
1238 | * perf_install_in_context(); | |
1239 | * | |
1240 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1241 | * quiesce the event, after which we can install it in the new location. This | |
1242 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1243 | * while in transit. Therefore all such accessors should also acquire | |
1244 | * perf_event_context::mutex to serialize against this. | |
1245 | * | |
1246 | * However; because event->ctx can change while we're waiting to acquire | |
1247 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1248 | * function. | |
1249 | * | |
1250 | * Lock order: | |
79c9ce57 | 1251 | * cred_guard_mutex |
f63a8daa PZ |
1252 | * task_struct::perf_event_mutex |
1253 | * perf_event_context::mutex | |
f63a8daa | 1254 | * perf_event::child_mutex; |
07c4a776 | 1255 | * perf_event_context::lock |
f63a8daa PZ |
1256 | * perf_event::mmap_mutex |
1257 | * mmap_sem | |
82d94856 PZ |
1258 | * |
1259 | * cpu_hotplug_lock | |
1260 | * pmus_lock | |
1261 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1262 | */ |
a83fe28e PZ |
1263 | static struct perf_event_context * |
1264 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1265 | { |
1266 | struct perf_event_context *ctx; | |
1267 | ||
1268 | again: | |
1269 | rcu_read_lock(); | |
6aa7de05 | 1270 | ctx = READ_ONCE(event->ctx); |
f63a8daa PZ |
1271 | if (!atomic_inc_not_zero(&ctx->refcount)) { |
1272 | rcu_read_unlock(); | |
1273 | goto again; | |
1274 | } | |
1275 | rcu_read_unlock(); | |
1276 | ||
a83fe28e | 1277 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1278 | if (event->ctx != ctx) { |
1279 | mutex_unlock(&ctx->mutex); | |
1280 | put_ctx(ctx); | |
1281 | goto again; | |
1282 | } | |
1283 | ||
1284 | return ctx; | |
1285 | } | |
1286 | ||
a83fe28e PZ |
1287 | static inline struct perf_event_context * |
1288 | perf_event_ctx_lock(struct perf_event *event) | |
1289 | { | |
1290 | return perf_event_ctx_lock_nested(event, 0); | |
1291 | } | |
1292 | ||
f63a8daa PZ |
1293 | static void perf_event_ctx_unlock(struct perf_event *event, |
1294 | struct perf_event_context *ctx) | |
1295 | { | |
1296 | mutex_unlock(&ctx->mutex); | |
1297 | put_ctx(ctx); | |
1298 | } | |
1299 | ||
211de6eb PZ |
1300 | /* |
1301 | * This must be done under the ctx->lock, such as to serialize against | |
1302 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1303 | * calling scheduler related locks and ctx->lock nests inside those. | |
1304 | */ | |
1305 | static __must_check struct perf_event_context * | |
1306 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1307 | { |
211de6eb PZ |
1308 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1309 | ||
1310 | lockdep_assert_held(&ctx->lock); | |
1311 | ||
1312 | if (parent_ctx) | |
71a851b4 | 1313 | ctx->parent_ctx = NULL; |
5a3126d4 | 1314 | ctx->generation++; |
211de6eb PZ |
1315 | |
1316 | return parent_ctx; | |
71a851b4 PZ |
1317 | } |
1318 | ||
1d953111 ON |
1319 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1320 | enum pid_type type) | |
6844c09d | 1321 | { |
1d953111 | 1322 | u32 nr; |
6844c09d ACM |
1323 | /* |
1324 | * only top level events have the pid namespace they were created in | |
1325 | */ | |
1326 | if (event->parent) | |
1327 | event = event->parent; | |
1328 | ||
1d953111 ON |
1329 | nr = __task_pid_nr_ns(p, type, event->ns); |
1330 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1331 | if (!nr && !pid_alive(p)) | |
1332 | nr = -1; | |
1333 | return nr; | |
6844c09d ACM |
1334 | } |
1335 | ||
1d953111 | 1336 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1337 | { |
6883f81a | 1338 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1339 | } |
6844c09d | 1340 | |
1d953111 ON |
1341 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1342 | { | |
1343 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1344 | } |
1345 | ||
7f453c24 | 1346 | /* |
cdd6c482 | 1347 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1348 | * to userspace. |
1349 | */ | |
cdd6c482 | 1350 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1351 | { |
cdd6c482 | 1352 | u64 id = event->id; |
7f453c24 | 1353 | |
cdd6c482 IM |
1354 | if (event->parent) |
1355 | id = event->parent->id; | |
7f453c24 PZ |
1356 | |
1357 | return id; | |
1358 | } | |
1359 | ||
25346b93 | 1360 | /* |
cdd6c482 | 1361 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1362 | * |
25346b93 PM |
1363 | * This has to cope with with the fact that until it is locked, |
1364 | * the context could get moved to another task. | |
1365 | */ | |
cdd6c482 | 1366 | static struct perf_event_context * |
8dc85d54 | 1367 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1368 | { |
cdd6c482 | 1369 | struct perf_event_context *ctx; |
25346b93 | 1370 | |
9ed6060d | 1371 | retry: |
058ebd0e PZ |
1372 | /* |
1373 | * One of the few rules of preemptible RCU is that one cannot do | |
1374 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1375 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1376 | * rcu_read_unlock_special(). |
1377 | * | |
1378 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1379 | * side critical section has interrupts disabled. |
058ebd0e | 1380 | */ |
2fd59077 | 1381 | local_irq_save(*flags); |
058ebd0e | 1382 | rcu_read_lock(); |
8dc85d54 | 1383 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1384 | if (ctx) { |
1385 | /* | |
1386 | * If this context is a clone of another, it might | |
1387 | * get swapped for another underneath us by | |
cdd6c482 | 1388 | * perf_event_task_sched_out, though the |
25346b93 PM |
1389 | * rcu_read_lock() protects us from any context |
1390 | * getting freed. Lock the context and check if it | |
1391 | * got swapped before we could get the lock, and retry | |
1392 | * if so. If we locked the right context, then it | |
1393 | * can't get swapped on us any more. | |
1394 | */ | |
2fd59077 | 1395 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1396 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1397 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1398 | rcu_read_unlock(); |
2fd59077 | 1399 | local_irq_restore(*flags); |
25346b93 PM |
1400 | goto retry; |
1401 | } | |
b49a9e7e | 1402 | |
63b6da39 PZ |
1403 | if (ctx->task == TASK_TOMBSTONE || |
1404 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1405 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1406 | ctx = NULL; |
828b6f0e PZ |
1407 | } else { |
1408 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1409 | } |
25346b93 PM |
1410 | } |
1411 | rcu_read_unlock(); | |
2fd59077 PM |
1412 | if (!ctx) |
1413 | local_irq_restore(*flags); | |
25346b93 PM |
1414 | return ctx; |
1415 | } | |
1416 | ||
1417 | /* | |
1418 | * Get the context for a task and increment its pin_count so it | |
1419 | * can't get swapped to another task. This also increments its | |
1420 | * reference count so that the context can't get freed. | |
1421 | */ | |
8dc85d54 PZ |
1422 | static struct perf_event_context * |
1423 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1424 | { |
cdd6c482 | 1425 | struct perf_event_context *ctx; |
25346b93 PM |
1426 | unsigned long flags; |
1427 | ||
8dc85d54 | 1428 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1429 | if (ctx) { |
1430 | ++ctx->pin_count; | |
e625cce1 | 1431 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1432 | } |
1433 | return ctx; | |
1434 | } | |
1435 | ||
cdd6c482 | 1436 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1437 | { |
1438 | unsigned long flags; | |
1439 | ||
e625cce1 | 1440 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1441 | --ctx->pin_count; |
e625cce1 | 1442 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1443 | } |
1444 | ||
f67218c3 PZ |
1445 | /* |
1446 | * Update the record of the current time in a context. | |
1447 | */ | |
1448 | static void update_context_time(struct perf_event_context *ctx) | |
1449 | { | |
1450 | u64 now = perf_clock(); | |
1451 | ||
1452 | ctx->time += now - ctx->timestamp; | |
1453 | ctx->timestamp = now; | |
1454 | } | |
1455 | ||
4158755d SE |
1456 | static u64 perf_event_time(struct perf_event *event) |
1457 | { | |
1458 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1459 | |
1460 | if (is_cgroup_event(event)) | |
1461 | return perf_cgroup_event_time(event); | |
1462 | ||
4158755d SE |
1463 | return ctx ? ctx->time : 0; |
1464 | } | |
1465 | ||
487f05e1 AS |
1466 | static enum event_type_t get_event_type(struct perf_event *event) |
1467 | { | |
1468 | struct perf_event_context *ctx = event->ctx; | |
1469 | enum event_type_t event_type; | |
1470 | ||
1471 | lockdep_assert_held(&ctx->lock); | |
1472 | ||
3bda69c1 AS |
1473 | /* |
1474 | * It's 'group type', really, because if our group leader is | |
1475 | * pinned, so are we. | |
1476 | */ | |
1477 | if (event->group_leader != event) | |
1478 | event = event->group_leader; | |
1479 | ||
487f05e1 AS |
1480 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1481 | if (!ctx->task) | |
1482 | event_type |= EVENT_CPU; | |
1483 | ||
1484 | return event_type; | |
1485 | } | |
1486 | ||
8e1a2031 | 1487 | /* |
161c85fa | 1488 | * Helper function to initialize event group nodes. |
8e1a2031 | 1489 | */ |
161c85fa | 1490 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1491 | { |
1492 | RB_CLEAR_NODE(&event->group_node); | |
1493 | event->group_index = 0; | |
1494 | } | |
1495 | ||
1496 | /* | |
1497 | * Extract pinned or flexible groups from the context | |
161c85fa | 1498 | * based on event attrs bits. |
8e1a2031 AB |
1499 | */ |
1500 | static struct perf_event_groups * | |
1501 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1502 | { |
1503 | if (event->attr.pinned) | |
1504 | return &ctx->pinned_groups; | |
1505 | else | |
1506 | return &ctx->flexible_groups; | |
1507 | } | |
1508 | ||
8e1a2031 | 1509 | /* |
161c85fa | 1510 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1511 | */ |
161c85fa | 1512 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1513 | { |
1514 | groups->tree = RB_ROOT; | |
1515 | groups->index = 0; | |
1516 | } | |
1517 | ||
1518 | /* | |
1519 | * Compare function for event groups; | |
161c85fa PZ |
1520 | * |
1521 | * Implements complex key that first sorts by CPU and then by virtual index | |
1522 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1523 | */ |
161c85fa PZ |
1524 | static bool |
1525 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1526 | { |
161c85fa PZ |
1527 | if (left->cpu < right->cpu) |
1528 | return true; | |
1529 | if (left->cpu > right->cpu) | |
1530 | return false; | |
1531 | ||
1532 | if (left->group_index < right->group_index) | |
1533 | return true; | |
1534 | if (left->group_index > right->group_index) | |
1535 | return false; | |
1536 | ||
1537 | return false; | |
8e1a2031 AB |
1538 | } |
1539 | ||
1540 | /* | |
161c85fa PZ |
1541 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1542 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1543 | * subtree. | |
8e1a2031 AB |
1544 | */ |
1545 | static void | |
1546 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1547 | struct perf_event *event) |
8e1a2031 AB |
1548 | { |
1549 | struct perf_event *node_event; | |
1550 | struct rb_node *parent; | |
1551 | struct rb_node **node; | |
1552 | ||
1553 | event->group_index = ++groups->index; | |
1554 | ||
1555 | node = &groups->tree.rb_node; | |
1556 | parent = *node; | |
1557 | ||
1558 | while (*node) { | |
1559 | parent = *node; | |
161c85fa | 1560 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1561 | |
1562 | if (perf_event_groups_less(event, node_event)) | |
1563 | node = &parent->rb_left; | |
1564 | else | |
1565 | node = &parent->rb_right; | |
1566 | } | |
1567 | ||
1568 | rb_link_node(&event->group_node, parent, node); | |
1569 | rb_insert_color(&event->group_node, &groups->tree); | |
1570 | } | |
1571 | ||
1572 | /* | |
161c85fa | 1573 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1574 | */ |
1575 | static void | |
1576 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1577 | { | |
1578 | struct perf_event_groups *groups; | |
1579 | ||
1580 | groups = get_event_groups(event, ctx); | |
1581 | perf_event_groups_insert(groups, event); | |
1582 | } | |
1583 | ||
1584 | /* | |
161c85fa | 1585 | * Delete a group from a tree. |
8e1a2031 AB |
1586 | */ |
1587 | static void | |
1588 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1589 | struct perf_event *event) |
8e1a2031 | 1590 | { |
161c85fa PZ |
1591 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1592 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1593 | |
161c85fa | 1594 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1595 | init_event_group(event); |
1596 | } | |
1597 | ||
1598 | /* | |
161c85fa | 1599 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1600 | */ |
1601 | static void | |
1602 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1603 | { | |
1604 | struct perf_event_groups *groups; | |
1605 | ||
1606 | groups = get_event_groups(event, ctx); | |
1607 | perf_event_groups_delete(groups, event); | |
1608 | } | |
1609 | ||
1610 | /* | |
161c85fa | 1611 | * Get the leftmost event in the @cpu subtree. |
8e1a2031 AB |
1612 | */ |
1613 | static struct perf_event * | |
1614 | perf_event_groups_first(struct perf_event_groups *groups, int cpu) | |
1615 | { | |
1616 | struct perf_event *node_event = NULL, *match = NULL; | |
1617 | struct rb_node *node = groups->tree.rb_node; | |
1618 | ||
1619 | while (node) { | |
161c85fa | 1620 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1621 | |
1622 | if (cpu < node_event->cpu) { | |
1623 | node = node->rb_left; | |
1624 | } else if (cpu > node_event->cpu) { | |
1625 | node = node->rb_right; | |
1626 | } else { | |
1627 | match = node_event; | |
1628 | node = node->rb_left; | |
1629 | } | |
1630 | } | |
1631 | ||
1632 | return match; | |
1633 | } | |
1634 | ||
1cac7b1a PZ |
1635 | /* |
1636 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1637 | */ | |
1638 | static struct perf_event * | |
1639 | perf_event_groups_next(struct perf_event *event) | |
1640 | { | |
1641 | struct perf_event *next; | |
1642 | ||
1643 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
1644 | if (next && next->cpu == event->cpu) | |
1645 | return next; | |
1646 | ||
1647 | return NULL; | |
1648 | } | |
1649 | ||
8e1a2031 | 1650 | /* |
161c85fa | 1651 | * Iterate through the whole groups tree. |
8e1a2031 | 1652 | */ |
6e6804d2 PZ |
1653 | #define perf_event_groups_for_each(event, groups) \ |
1654 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1655 | typeof(*event), group_node); event; \ | |
1656 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1657 | typeof(*event), group_node)) | |
8e1a2031 | 1658 | |
fccc714b | 1659 | /* |
788faab7 | 1660 | * Add an event from the lists for its context. |
fccc714b PZ |
1661 | * Must be called with ctx->mutex and ctx->lock held. |
1662 | */ | |
04289bb9 | 1663 | static void |
cdd6c482 | 1664 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1665 | { |
c994d613 PZ |
1666 | lockdep_assert_held(&ctx->lock); |
1667 | ||
8a49542c PZ |
1668 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1669 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1670 | |
0d3d73aa PZ |
1671 | event->tstamp = perf_event_time(event); |
1672 | ||
04289bb9 | 1673 | /* |
8a49542c PZ |
1674 | * If we're a stand alone event or group leader, we go to the context |
1675 | * list, group events are kept attached to the group so that | |
1676 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1677 | */ |
8a49542c | 1678 | if (event->group_leader == event) { |
4ff6a8de | 1679 | event->group_caps = event->event_caps; |
8e1a2031 | 1680 | add_event_to_groups(event, ctx); |
5c148194 | 1681 | } |
592903cd | 1682 | |
db4a8356 | 1683 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1684 | |
cdd6c482 IM |
1685 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1686 | ctx->nr_events++; | |
1687 | if (event->attr.inherit_stat) | |
bfbd3381 | 1688 | ctx->nr_stat++; |
5a3126d4 PZ |
1689 | |
1690 | ctx->generation++; | |
04289bb9 IM |
1691 | } |
1692 | ||
0231bb53 JO |
1693 | /* |
1694 | * Initialize event state based on the perf_event_attr::disabled. | |
1695 | */ | |
1696 | static inline void perf_event__state_init(struct perf_event *event) | |
1697 | { | |
1698 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1699 | PERF_EVENT_STATE_INACTIVE; | |
1700 | } | |
1701 | ||
a723968c | 1702 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1703 | { |
1704 | int entry = sizeof(u64); /* value */ | |
1705 | int size = 0; | |
1706 | int nr = 1; | |
1707 | ||
1708 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1709 | size += sizeof(u64); | |
1710 | ||
1711 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1712 | size += sizeof(u64); | |
1713 | ||
1714 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1715 | entry += sizeof(u64); | |
1716 | ||
1717 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1718 | nr += nr_siblings; |
c320c7b7 ACM |
1719 | size += sizeof(u64); |
1720 | } | |
1721 | ||
1722 | size += entry * nr; | |
1723 | event->read_size = size; | |
1724 | } | |
1725 | ||
a723968c | 1726 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1727 | { |
1728 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1729 | u16 size = 0; |
1730 | ||
c320c7b7 ACM |
1731 | if (sample_type & PERF_SAMPLE_IP) |
1732 | size += sizeof(data->ip); | |
1733 | ||
6844c09d ACM |
1734 | if (sample_type & PERF_SAMPLE_ADDR) |
1735 | size += sizeof(data->addr); | |
1736 | ||
1737 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1738 | size += sizeof(data->period); | |
1739 | ||
c3feedf2 AK |
1740 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1741 | size += sizeof(data->weight); | |
1742 | ||
6844c09d ACM |
1743 | if (sample_type & PERF_SAMPLE_READ) |
1744 | size += event->read_size; | |
1745 | ||
d6be9ad6 SE |
1746 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1747 | size += sizeof(data->data_src.val); | |
1748 | ||
fdfbbd07 AK |
1749 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1750 | size += sizeof(data->txn); | |
1751 | ||
fc7ce9c7 KL |
1752 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1753 | size += sizeof(data->phys_addr); | |
1754 | ||
6844c09d ACM |
1755 | event->header_size = size; |
1756 | } | |
1757 | ||
a723968c PZ |
1758 | /* |
1759 | * Called at perf_event creation and when events are attached/detached from a | |
1760 | * group. | |
1761 | */ | |
1762 | static void perf_event__header_size(struct perf_event *event) | |
1763 | { | |
1764 | __perf_event_read_size(event, | |
1765 | event->group_leader->nr_siblings); | |
1766 | __perf_event_header_size(event, event->attr.sample_type); | |
1767 | } | |
1768 | ||
6844c09d ACM |
1769 | static void perf_event__id_header_size(struct perf_event *event) |
1770 | { | |
1771 | struct perf_sample_data *data; | |
1772 | u64 sample_type = event->attr.sample_type; | |
1773 | u16 size = 0; | |
1774 | ||
c320c7b7 ACM |
1775 | if (sample_type & PERF_SAMPLE_TID) |
1776 | size += sizeof(data->tid_entry); | |
1777 | ||
1778 | if (sample_type & PERF_SAMPLE_TIME) | |
1779 | size += sizeof(data->time); | |
1780 | ||
ff3d527c AH |
1781 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1782 | size += sizeof(data->id); | |
1783 | ||
c320c7b7 ACM |
1784 | if (sample_type & PERF_SAMPLE_ID) |
1785 | size += sizeof(data->id); | |
1786 | ||
1787 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1788 | size += sizeof(data->stream_id); | |
1789 | ||
1790 | if (sample_type & PERF_SAMPLE_CPU) | |
1791 | size += sizeof(data->cpu_entry); | |
1792 | ||
6844c09d | 1793 | event->id_header_size = size; |
c320c7b7 ACM |
1794 | } |
1795 | ||
a723968c PZ |
1796 | static bool perf_event_validate_size(struct perf_event *event) |
1797 | { | |
1798 | /* | |
1799 | * The values computed here will be over-written when we actually | |
1800 | * attach the event. | |
1801 | */ | |
1802 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1803 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1804 | perf_event__id_header_size(event); | |
1805 | ||
1806 | /* | |
1807 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1808 | * Conservative limit to allow for callchains and other variable fields. | |
1809 | */ | |
1810 | if (event->read_size + event->header_size + | |
1811 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1812 | return false; | |
1813 | ||
1814 | return true; | |
1815 | } | |
1816 | ||
8a49542c PZ |
1817 | static void perf_group_attach(struct perf_event *event) |
1818 | { | |
c320c7b7 | 1819 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1820 | |
a76a82a3 PZ |
1821 | lockdep_assert_held(&event->ctx->lock); |
1822 | ||
74c3337c PZ |
1823 | /* |
1824 | * We can have double attach due to group movement in perf_event_open. | |
1825 | */ | |
1826 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1827 | return; | |
1828 | ||
8a49542c PZ |
1829 | event->attach_state |= PERF_ATTACH_GROUP; |
1830 | ||
1831 | if (group_leader == event) | |
1832 | return; | |
1833 | ||
652884fe PZ |
1834 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1835 | ||
4ff6a8de | 1836 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1837 | |
8343aae6 | 1838 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1839 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1840 | |
1841 | perf_event__header_size(group_leader); | |
1842 | ||
edb39592 | 1843 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1844 | perf_event__header_size(pos); |
8a49542c PZ |
1845 | } |
1846 | ||
a63eaf34 | 1847 | /* |
788faab7 | 1848 | * Remove an event from the lists for its context. |
fccc714b | 1849 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1850 | */ |
04289bb9 | 1851 | static void |
cdd6c482 | 1852 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1853 | { |
652884fe PZ |
1854 | WARN_ON_ONCE(event->ctx != ctx); |
1855 | lockdep_assert_held(&ctx->lock); | |
1856 | ||
8a49542c PZ |
1857 | /* |
1858 | * We can have double detach due to exit/hot-unplug + close. | |
1859 | */ | |
1860 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1861 | return; |
8a49542c PZ |
1862 | |
1863 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1864 | ||
db4a8356 | 1865 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1866 | |
cdd6c482 IM |
1867 | ctx->nr_events--; |
1868 | if (event->attr.inherit_stat) | |
bfbd3381 | 1869 | ctx->nr_stat--; |
8bc20959 | 1870 | |
cdd6c482 | 1871 | list_del_rcu(&event->event_entry); |
04289bb9 | 1872 | |
8a49542c | 1873 | if (event->group_leader == event) |
8e1a2031 | 1874 | del_event_from_groups(event, ctx); |
5c148194 | 1875 | |
b2e74a26 SE |
1876 | /* |
1877 | * If event was in error state, then keep it | |
1878 | * that way, otherwise bogus counts will be | |
1879 | * returned on read(). The only way to get out | |
1880 | * of error state is by explicit re-enabling | |
1881 | * of the event | |
1882 | */ | |
1883 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1884 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1885 | |
1886 | ctx->generation++; | |
050735b0 PZ |
1887 | } |
1888 | ||
8a49542c | 1889 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1890 | { |
1891 | struct perf_event *sibling, *tmp; | |
6668128a | 1892 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 1893 | |
6668128a | 1894 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 1895 | |
8a49542c PZ |
1896 | /* |
1897 | * We can have double detach due to exit/hot-unplug + close. | |
1898 | */ | |
1899 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1900 | return; | |
1901 | ||
1902 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1903 | ||
1904 | /* | |
1905 | * If this is a sibling, remove it from its group. | |
1906 | */ | |
1907 | if (event->group_leader != event) { | |
8343aae6 | 1908 | list_del_init(&event->sibling_list); |
8a49542c | 1909 | event->group_leader->nr_siblings--; |
c320c7b7 | 1910 | goto out; |
8a49542c PZ |
1911 | } |
1912 | ||
04289bb9 | 1913 | /* |
cdd6c482 IM |
1914 | * If this was a group event with sibling events then |
1915 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1916 | * to whatever list we are on. |
04289bb9 | 1917 | */ |
8343aae6 | 1918 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 1919 | |
04289bb9 | 1920 | sibling->group_leader = sibling; |
24868367 | 1921 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
1922 | |
1923 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1924 | sibling->group_caps = event->group_caps; |
652884fe | 1925 | |
8e1a2031 | 1926 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 1927 | add_event_to_groups(sibling, event->ctx); |
6668128a PZ |
1928 | |
1929 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) { | |
1930 | struct list_head *list = sibling->attr.pinned ? | |
1931 | &ctx->pinned_active : &ctx->flexible_active; | |
1932 | ||
1933 | list_add_tail(&sibling->active_list, list); | |
1934 | } | |
8e1a2031 AB |
1935 | } |
1936 | ||
652884fe | 1937 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 1938 | } |
c320c7b7 ACM |
1939 | |
1940 | out: | |
1941 | perf_event__header_size(event->group_leader); | |
1942 | ||
edb39592 | 1943 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 1944 | perf_event__header_size(tmp); |
04289bb9 IM |
1945 | } |
1946 | ||
fadfe7be JO |
1947 | static bool is_orphaned_event(struct perf_event *event) |
1948 | { | |
a69b0ca4 | 1949 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1950 | } |
1951 | ||
2c81a647 | 1952 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1953 | { |
1954 | struct pmu *pmu = event->pmu; | |
1955 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1956 | } | |
1957 | ||
2c81a647 MR |
1958 | /* |
1959 | * Check whether we should attempt to schedule an event group based on | |
1960 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1961 | * potentially with a SW leader, so we must check all the filters, to | |
1962 | * determine whether a group is schedulable: | |
1963 | */ | |
1964 | static inline int pmu_filter_match(struct perf_event *event) | |
1965 | { | |
edb39592 | 1966 | struct perf_event *sibling; |
2c81a647 MR |
1967 | |
1968 | if (!__pmu_filter_match(event)) | |
1969 | return 0; | |
1970 | ||
edb39592 PZ |
1971 | for_each_sibling_event(sibling, event) { |
1972 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
1973 | return 0; |
1974 | } | |
1975 | ||
1976 | return 1; | |
1977 | } | |
1978 | ||
fa66f07a SE |
1979 | static inline int |
1980 | event_filter_match(struct perf_event *event) | |
1981 | { | |
0b8f1e2e PZ |
1982 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1983 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1984 | } |
1985 | ||
9ffcfa6f SE |
1986 | static void |
1987 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1988 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1989 | struct perf_event_context *ctx) |
3b6f9e5c | 1990 | { |
0d3d73aa | 1991 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
1992 | |
1993 | WARN_ON_ONCE(event->ctx != ctx); | |
1994 | lockdep_assert_held(&ctx->lock); | |
1995 | ||
cdd6c482 | 1996 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1997 | return; |
3b6f9e5c | 1998 | |
6668128a PZ |
1999 | /* |
2000 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2001 | * we can schedule events _OUT_ individually through things like | |
2002 | * __perf_remove_from_context(). | |
2003 | */ | |
2004 | list_del_init(&event->active_list); | |
2005 | ||
44377277 AS |
2006 | perf_pmu_disable(event->pmu); |
2007 | ||
28a967c3 PZ |
2008 | event->pmu->del(event, 0); |
2009 | event->oncpu = -1; | |
0d3d73aa | 2010 | |
cdd6c482 IM |
2011 | if (event->pending_disable) { |
2012 | event->pending_disable = 0; | |
0d3d73aa | 2013 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2014 | } |
0d3d73aa | 2015 | perf_event_set_state(event, state); |
3b6f9e5c | 2016 | |
cdd6c482 | 2017 | if (!is_software_event(event)) |
3b6f9e5c | 2018 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2019 | if (!--ctx->nr_active) |
2020 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2021 | if (event->attr.freq && event->attr.sample_freq) |
2022 | ctx->nr_freq--; | |
cdd6c482 | 2023 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2024 | cpuctx->exclusive = 0; |
44377277 AS |
2025 | |
2026 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2027 | } |
2028 | ||
d859e29f | 2029 | static void |
cdd6c482 | 2030 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2031 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2032 | struct perf_event_context *ctx) |
d859e29f | 2033 | { |
cdd6c482 | 2034 | struct perf_event *event; |
0d3d73aa PZ |
2035 | |
2036 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2037 | return; | |
d859e29f | 2038 | |
3f005e7d MR |
2039 | perf_pmu_disable(ctx->pmu); |
2040 | ||
cdd6c482 | 2041 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2042 | |
2043 | /* | |
2044 | * Schedule out siblings (if any): | |
2045 | */ | |
edb39592 | 2046 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2047 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2048 | |
3f005e7d MR |
2049 | perf_pmu_enable(ctx->pmu); |
2050 | ||
0d3d73aa | 2051 | if (group_event->attr.exclusive) |
d859e29f PM |
2052 | cpuctx->exclusive = 0; |
2053 | } | |
2054 | ||
45a0e07a | 2055 | #define DETACH_GROUP 0x01UL |
0017960f | 2056 | |
0793a61d | 2057 | /* |
cdd6c482 | 2058 | * Cross CPU call to remove a performance event |
0793a61d | 2059 | * |
cdd6c482 | 2060 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2061 | * remove it from the context list. |
2062 | */ | |
fae3fde6 PZ |
2063 | static void |
2064 | __perf_remove_from_context(struct perf_event *event, | |
2065 | struct perf_cpu_context *cpuctx, | |
2066 | struct perf_event_context *ctx, | |
2067 | void *info) | |
0793a61d | 2068 | { |
45a0e07a | 2069 | unsigned long flags = (unsigned long)info; |
0793a61d | 2070 | |
3c5c8711 PZ |
2071 | if (ctx->is_active & EVENT_TIME) { |
2072 | update_context_time(ctx); | |
2073 | update_cgrp_time_from_cpuctx(cpuctx); | |
2074 | } | |
2075 | ||
cdd6c482 | 2076 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2077 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2078 | perf_group_detach(event); |
cdd6c482 | 2079 | list_del_event(event, ctx); |
39a43640 PZ |
2080 | |
2081 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2082 | ctx->is_active = 0; |
39a43640 PZ |
2083 | if (ctx->task) { |
2084 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2085 | cpuctx->task_ctx = NULL; | |
2086 | } | |
64ce3126 | 2087 | } |
0793a61d TG |
2088 | } |
2089 | ||
0793a61d | 2090 | /* |
cdd6c482 | 2091 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2092 | * |
cdd6c482 IM |
2093 | * If event->ctx is a cloned context, callers must make sure that |
2094 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2095 | * remains valid. This is OK when called from perf_release since |
2096 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2097 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2098 | * context has been detached from its task. |
0793a61d | 2099 | */ |
45a0e07a | 2100 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2101 | { |
a76a82a3 PZ |
2102 | struct perf_event_context *ctx = event->ctx; |
2103 | ||
2104 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2105 | |
45a0e07a | 2106 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2107 | |
2108 | /* | |
2109 | * The above event_function_call() can NO-OP when it hits | |
2110 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2111 | * from the context (by perf_event_exit_event()) but the grouping | |
2112 | * might still be in-tact. | |
2113 | */ | |
2114 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2115 | if ((flags & DETACH_GROUP) && | |
2116 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2117 | /* | |
2118 | * Since in that case we cannot possibly be scheduled, simply | |
2119 | * detach now. | |
2120 | */ | |
2121 | raw_spin_lock_irq(&ctx->lock); | |
2122 | perf_group_detach(event); | |
2123 | raw_spin_unlock_irq(&ctx->lock); | |
2124 | } | |
0793a61d TG |
2125 | } |
2126 | ||
d859e29f | 2127 | /* |
cdd6c482 | 2128 | * Cross CPU call to disable a performance event |
d859e29f | 2129 | */ |
fae3fde6 PZ |
2130 | static void __perf_event_disable(struct perf_event *event, |
2131 | struct perf_cpu_context *cpuctx, | |
2132 | struct perf_event_context *ctx, | |
2133 | void *info) | |
7b648018 | 2134 | { |
fae3fde6 PZ |
2135 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2136 | return; | |
7b648018 | 2137 | |
3c5c8711 PZ |
2138 | if (ctx->is_active & EVENT_TIME) { |
2139 | update_context_time(ctx); | |
2140 | update_cgrp_time_from_event(event); | |
2141 | } | |
2142 | ||
fae3fde6 PZ |
2143 | if (event == event->group_leader) |
2144 | group_sched_out(event, cpuctx, ctx); | |
2145 | else | |
2146 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2147 | |
2148 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2149 | } |
2150 | ||
d859e29f | 2151 | /* |
788faab7 | 2152 | * Disable an event. |
c93f7669 | 2153 | * |
cdd6c482 IM |
2154 | * If event->ctx is a cloned context, callers must make sure that |
2155 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2156 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
2157 | * perf_event_for_each_child or perf_event_for_each because they |
2158 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2159 | * goes to exit will block in perf_event_exit_event(). |
2160 | * | |
cdd6c482 | 2161 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2162 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2163 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2164 | */ |
f63a8daa | 2165 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2166 | { |
cdd6c482 | 2167 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2168 | |
e625cce1 | 2169 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2170 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2171 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2172 | return; |
53cfbf59 | 2173 | } |
e625cce1 | 2174 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2175 | |
fae3fde6 PZ |
2176 | event_function_call(event, __perf_event_disable, NULL); |
2177 | } | |
2178 | ||
2179 | void perf_event_disable_local(struct perf_event *event) | |
2180 | { | |
2181 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2182 | } |
f63a8daa PZ |
2183 | |
2184 | /* | |
2185 | * Strictly speaking kernel users cannot create groups and therefore this | |
2186 | * interface does not need the perf_event_ctx_lock() magic. | |
2187 | */ | |
2188 | void perf_event_disable(struct perf_event *event) | |
2189 | { | |
2190 | struct perf_event_context *ctx; | |
2191 | ||
2192 | ctx = perf_event_ctx_lock(event); | |
2193 | _perf_event_disable(event); | |
2194 | perf_event_ctx_unlock(event, ctx); | |
2195 | } | |
dcfce4a0 | 2196 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2197 | |
5aab90ce JO |
2198 | void perf_event_disable_inatomic(struct perf_event *event) |
2199 | { | |
2200 | event->pending_disable = 1; | |
2201 | irq_work_queue(&event->pending); | |
2202 | } | |
2203 | ||
e5d1367f | 2204 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2205 | struct perf_event_context *ctx) |
e5d1367f SE |
2206 | { |
2207 | /* | |
2208 | * use the correct time source for the time snapshot | |
2209 | * | |
2210 | * We could get by without this by leveraging the | |
2211 | * fact that to get to this function, the caller | |
2212 | * has most likely already called update_context_time() | |
2213 | * and update_cgrp_time_xx() and thus both timestamp | |
2214 | * are identical (or very close). Given that tstamp is, | |
2215 | * already adjusted for cgroup, we could say that: | |
2216 | * tstamp - ctx->timestamp | |
2217 | * is equivalent to | |
2218 | * tstamp - cgrp->timestamp. | |
2219 | * | |
2220 | * Then, in perf_output_read(), the calculation would | |
2221 | * work with no changes because: | |
2222 | * - event is guaranteed scheduled in | |
2223 | * - no scheduled out in between | |
2224 | * - thus the timestamp would be the same | |
2225 | * | |
2226 | * But this is a bit hairy. | |
2227 | * | |
2228 | * So instead, we have an explicit cgroup call to remain | |
2229 | * within the time time source all along. We believe it | |
2230 | * is cleaner and simpler to understand. | |
2231 | */ | |
2232 | if (is_cgroup_event(event)) | |
0d3d73aa | 2233 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2234 | else |
0d3d73aa | 2235 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2236 | } |
2237 | ||
4fe757dd PZ |
2238 | #define MAX_INTERRUPTS (~0ULL) |
2239 | ||
2240 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2241 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2242 | |
235c7fc7 | 2243 | static int |
9ffcfa6f | 2244 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2245 | struct perf_cpu_context *cpuctx, |
6e37738a | 2246 | struct perf_event_context *ctx) |
235c7fc7 | 2247 | { |
44377277 | 2248 | int ret = 0; |
4158755d | 2249 | |
63342411 PZ |
2250 | lockdep_assert_held(&ctx->lock); |
2251 | ||
cdd6c482 | 2252 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2253 | return 0; |
2254 | ||
95ff4ca2 AS |
2255 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2256 | /* | |
0c1cbc18 PZ |
2257 | * Order event::oncpu write to happen before the ACTIVE state is |
2258 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2259 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2260 | */ |
2261 | smp_wmb(); | |
0d3d73aa | 2262 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2263 | |
2264 | /* | |
2265 | * Unthrottle events, since we scheduled we might have missed several | |
2266 | * ticks already, also for a heavily scheduling task there is little | |
2267 | * guarantee it'll get a tick in a timely manner. | |
2268 | */ | |
2269 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2270 | perf_log_throttle(event, 1); | |
2271 | event->hw.interrupts = 0; | |
2272 | } | |
2273 | ||
44377277 AS |
2274 | perf_pmu_disable(event->pmu); |
2275 | ||
0d3d73aa | 2276 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2277 | |
ec0d7729 AS |
2278 | perf_log_itrace_start(event); |
2279 | ||
a4eaf7f1 | 2280 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2281 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2282 | event->oncpu = -1; |
44377277 AS |
2283 | ret = -EAGAIN; |
2284 | goto out; | |
235c7fc7 IM |
2285 | } |
2286 | ||
cdd6c482 | 2287 | if (!is_software_event(event)) |
3b6f9e5c | 2288 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2289 | if (!ctx->nr_active++) |
2290 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2291 | if (event->attr.freq && event->attr.sample_freq) |
2292 | ctx->nr_freq++; | |
235c7fc7 | 2293 | |
cdd6c482 | 2294 | if (event->attr.exclusive) |
3b6f9e5c PM |
2295 | cpuctx->exclusive = 1; |
2296 | ||
44377277 AS |
2297 | out: |
2298 | perf_pmu_enable(event->pmu); | |
2299 | ||
2300 | return ret; | |
235c7fc7 IM |
2301 | } |
2302 | ||
6751b71e | 2303 | static int |
cdd6c482 | 2304 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2305 | struct perf_cpu_context *cpuctx, |
6e37738a | 2306 | struct perf_event_context *ctx) |
6751b71e | 2307 | { |
6bde9b6c | 2308 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2309 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2310 | |
cdd6c482 | 2311 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2312 | return 0; |
2313 | ||
fbbe0701 | 2314 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2315 | |
9ffcfa6f | 2316 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2317 | pmu->cancel_txn(pmu); |
272325c4 | 2318 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2319 | return -EAGAIN; |
90151c35 | 2320 | } |
6751b71e PM |
2321 | |
2322 | /* | |
2323 | * Schedule in siblings as one group (if any): | |
2324 | */ | |
edb39592 | 2325 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2326 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2327 | partial_group = event; |
6751b71e PM |
2328 | goto group_error; |
2329 | } | |
2330 | } | |
2331 | ||
9ffcfa6f | 2332 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2333 | return 0; |
9ffcfa6f | 2334 | |
6751b71e PM |
2335 | group_error: |
2336 | /* | |
2337 | * Groups can be scheduled in as one unit only, so undo any | |
2338 | * partial group before returning: | |
0d3d73aa | 2339 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2340 | */ |
edb39592 | 2341 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2342 | if (event == partial_group) |
0d3d73aa | 2343 | break; |
d7842da4 | 2344 | |
0d3d73aa | 2345 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2346 | } |
9ffcfa6f | 2347 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2348 | |
ad5133b7 | 2349 | pmu->cancel_txn(pmu); |
90151c35 | 2350 | |
272325c4 | 2351 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2352 | |
6751b71e PM |
2353 | return -EAGAIN; |
2354 | } | |
2355 | ||
3b6f9e5c | 2356 | /* |
cdd6c482 | 2357 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2358 | */ |
cdd6c482 | 2359 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2360 | struct perf_cpu_context *cpuctx, |
2361 | int can_add_hw) | |
2362 | { | |
2363 | /* | |
cdd6c482 | 2364 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2365 | */ |
4ff6a8de | 2366 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2367 | return 1; |
2368 | /* | |
2369 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2370 | * events can go on. |
3b6f9e5c PM |
2371 | */ |
2372 | if (cpuctx->exclusive) | |
2373 | return 0; | |
2374 | /* | |
2375 | * If this group is exclusive and there are already | |
cdd6c482 | 2376 | * events on the CPU, it can't go on. |
3b6f9e5c | 2377 | */ |
cdd6c482 | 2378 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2379 | return 0; |
2380 | /* | |
2381 | * Otherwise, try to add it if all previous groups were able | |
2382 | * to go on. | |
2383 | */ | |
2384 | return can_add_hw; | |
2385 | } | |
2386 | ||
cdd6c482 IM |
2387 | static void add_event_to_ctx(struct perf_event *event, |
2388 | struct perf_event_context *ctx) | |
53cfbf59 | 2389 | { |
cdd6c482 | 2390 | list_add_event(event, ctx); |
8a49542c | 2391 | perf_group_attach(event); |
53cfbf59 PM |
2392 | } |
2393 | ||
bd2afa49 PZ |
2394 | static void ctx_sched_out(struct perf_event_context *ctx, |
2395 | struct perf_cpu_context *cpuctx, | |
2396 | enum event_type_t event_type); | |
2c29ef0f PZ |
2397 | static void |
2398 | ctx_sched_in(struct perf_event_context *ctx, | |
2399 | struct perf_cpu_context *cpuctx, | |
2400 | enum event_type_t event_type, | |
2401 | struct task_struct *task); | |
fe4b04fa | 2402 | |
bd2afa49 | 2403 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2404 | struct perf_event_context *ctx, |
2405 | enum event_type_t event_type) | |
bd2afa49 PZ |
2406 | { |
2407 | if (!cpuctx->task_ctx) | |
2408 | return; | |
2409 | ||
2410 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2411 | return; | |
2412 | ||
487f05e1 | 2413 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2414 | } |
2415 | ||
dce5855b PZ |
2416 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2417 | struct perf_event_context *ctx, | |
2418 | struct task_struct *task) | |
2419 | { | |
2420 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2421 | if (ctx) | |
2422 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2423 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2424 | if (ctx) | |
2425 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2426 | } | |
2427 | ||
487f05e1 AS |
2428 | /* |
2429 | * We want to maintain the following priority of scheduling: | |
2430 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2431 | * - task pinned (EVENT_PINNED) | |
2432 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2433 | * - task flexible (EVENT_FLEXIBLE). | |
2434 | * | |
2435 | * In order to avoid unscheduling and scheduling back in everything every | |
2436 | * time an event is added, only do it for the groups of equal priority and | |
2437 | * below. | |
2438 | * | |
2439 | * This can be called after a batch operation on task events, in which case | |
2440 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2441 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2442 | */ | |
3e349507 | 2443 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2444 | struct perf_event_context *task_ctx, |
2445 | enum event_type_t event_type) | |
0017960f | 2446 | { |
bd903afe | 2447 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2448 | bool cpu_event = !!(event_type & EVENT_CPU); |
2449 | ||
2450 | /* | |
2451 | * If pinned groups are involved, flexible groups also need to be | |
2452 | * scheduled out. | |
2453 | */ | |
2454 | if (event_type & EVENT_PINNED) | |
2455 | event_type |= EVENT_FLEXIBLE; | |
2456 | ||
bd903afe SL |
2457 | ctx_event_type = event_type & EVENT_ALL; |
2458 | ||
3e349507 PZ |
2459 | perf_pmu_disable(cpuctx->ctx.pmu); |
2460 | if (task_ctx) | |
487f05e1 AS |
2461 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2462 | ||
2463 | /* | |
2464 | * Decide which cpu ctx groups to schedule out based on the types | |
2465 | * of events that caused rescheduling: | |
2466 | * - EVENT_CPU: schedule out corresponding groups; | |
2467 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2468 | * - otherwise, do nothing more. | |
2469 | */ | |
2470 | if (cpu_event) | |
2471 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2472 | else if (ctx_event_type & EVENT_PINNED) | |
2473 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2474 | ||
3e349507 PZ |
2475 | perf_event_sched_in(cpuctx, task_ctx, current); |
2476 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2477 | } |
2478 | ||
0793a61d | 2479 | /* |
cdd6c482 | 2480 | * Cross CPU call to install and enable a performance event |
682076ae | 2481 | * |
a096309b PZ |
2482 | * Very similar to remote_function() + event_function() but cannot assume that |
2483 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2484 | */ |
fe4b04fa | 2485 | static int __perf_install_in_context(void *info) |
0793a61d | 2486 | { |
a096309b PZ |
2487 | struct perf_event *event = info; |
2488 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2489 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2490 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2491 | bool reprogram = true; |
a096309b | 2492 | int ret = 0; |
0793a61d | 2493 | |
63b6da39 | 2494 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2495 | if (ctx->task) { |
b58f6b0d PZ |
2496 | raw_spin_lock(&ctx->lock); |
2497 | task_ctx = ctx; | |
a096309b | 2498 | |
63cae12b | 2499 | reprogram = (ctx->task == current); |
b58f6b0d | 2500 | |
39a43640 | 2501 | /* |
63cae12b PZ |
2502 | * If the task is running, it must be running on this CPU, |
2503 | * otherwise we cannot reprogram things. | |
2504 | * | |
2505 | * If its not running, we don't care, ctx->lock will | |
2506 | * serialize against it becoming runnable. | |
39a43640 | 2507 | */ |
63cae12b PZ |
2508 | if (task_curr(ctx->task) && !reprogram) { |
2509 | ret = -ESRCH; | |
2510 | goto unlock; | |
2511 | } | |
a096309b | 2512 | |
63cae12b | 2513 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2514 | } else if (task_ctx) { |
2515 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2516 | } |
b58f6b0d | 2517 | |
33801b94 | 2518 | #ifdef CONFIG_CGROUP_PERF |
2519 | if (is_cgroup_event(event)) { | |
2520 | /* | |
2521 | * If the current cgroup doesn't match the event's | |
2522 | * cgroup, we should not try to schedule it. | |
2523 | */ | |
2524 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2525 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2526 | event->cgrp->css.cgroup); | |
2527 | } | |
2528 | #endif | |
2529 | ||
63cae12b | 2530 | if (reprogram) { |
a096309b PZ |
2531 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2532 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2533 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2534 | } else { |
2535 | add_event_to_ctx(event, ctx); | |
2536 | } | |
2537 | ||
63b6da39 | 2538 | unlock: |
2c29ef0f | 2539 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2540 | |
a096309b | 2541 | return ret; |
0793a61d TG |
2542 | } |
2543 | ||
2544 | /* | |
a096309b PZ |
2545 | * Attach a performance event to a context. |
2546 | * | |
2547 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2548 | */ |
2549 | static void | |
cdd6c482 IM |
2550 | perf_install_in_context(struct perf_event_context *ctx, |
2551 | struct perf_event *event, | |
0793a61d TG |
2552 | int cpu) |
2553 | { | |
a096309b | 2554 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2555 | |
fe4b04fa PZ |
2556 | lockdep_assert_held(&ctx->mutex); |
2557 | ||
0cda4c02 YZ |
2558 | if (event->cpu != -1) |
2559 | event->cpu = cpu; | |
c3f00c70 | 2560 | |
0b8f1e2e PZ |
2561 | /* |
2562 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2563 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2564 | */ | |
2565 | smp_store_release(&event->ctx, ctx); | |
2566 | ||
a096309b PZ |
2567 | if (!task) { |
2568 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2569 | return; | |
2570 | } | |
2571 | ||
2572 | /* | |
2573 | * Should not happen, we validate the ctx is still alive before calling. | |
2574 | */ | |
2575 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2576 | return; | |
2577 | ||
39a43640 PZ |
2578 | /* |
2579 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2580 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2581 | * |
2582 | * Instead we use task_curr(), which tells us if the task is running. | |
2583 | * However, since we use task_curr() outside of rq::lock, we can race | |
2584 | * against the actual state. This means the result can be wrong. | |
2585 | * | |
2586 | * If we get a false positive, we retry, this is harmless. | |
2587 | * | |
2588 | * If we get a false negative, things are complicated. If we are after | |
2589 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2590 | * value must be correct. If we're before, it doesn't matter since | |
2591 | * perf_event_context_sched_in() will program the counter. | |
2592 | * | |
2593 | * However, this hinges on the remote context switch having observed | |
2594 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2595 | * ctx::lock in perf_event_context_sched_in(). | |
2596 | * | |
2597 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2598 | * we know any future context switch of task must see the | |
2599 | * perf_event_ctpx[] store. | |
39a43640 | 2600 | */ |
63cae12b | 2601 | |
63b6da39 | 2602 | /* |
63cae12b PZ |
2603 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2604 | * task_cpu() load, such that if the IPI then does not find the task | |
2605 | * running, a future context switch of that task must observe the | |
2606 | * store. | |
63b6da39 | 2607 | */ |
63cae12b PZ |
2608 | smp_mb(); |
2609 | again: | |
2610 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2611 | return; |
2612 | ||
2613 | raw_spin_lock_irq(&ctx->lock); | |
2614 | task = ctx->task; | |
84c4e620 | 2615 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2616 | /* |
2617 | * Cannot happen because we already checked above (which also | |
2618 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2619 | * against perf_event_exit_task_context(). | |
2620 | */ | |
63b6da39 PZ |
2621 | raw_spin_unlock_irq(&ctx->lock); |
2622 | return; | |
2623 | } | |
39a43640 | 2624 | /* |
63cae12b PZ |
2625 | * If the task is not running, ctx->lock will avoid it becoming so, |
2626 | * thus we can safely install the event. | |
39a43640 | 2627 | */ |
63cae12b PZ |
2628 | if (task_curr(task)) { |
2629 | raw_spin_unlock_irq(&ctx->lock); | |
2630 | goto again; | |
2631 | } | |
2632 | add_event_to_ctx(event, ctx); | |
2633 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2634 | } |
2635 | ||
d859e29f | 2636 | /* |
cdd6c482 | 2637 | * Cross CPU call to enable a performance event |
d859e29f | 2638 | */ |
fae3fde6 PZ |
2639 | static void __perf_event_enable(struct perf_event *event, |
2640 | struct perf_cpu_context *cpuctx, | |
2641 | struct perf_event_context *ctx, | |
2642 | void *info) | |
04289bb9 | 2643 | { |
cdd6c482 | 2644 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2645 | struct perf_event_context *task_ctx; |
04289bb9 | 2646 | |
6e801e01 PZ |
2647 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2648 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2649 | return; |
3cbed429 | 2650 | |
bd2afa49 PZ |
2651 | if (ctx->is_active) |
2652 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2653 | ||
0d3d73aa | 2654 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2655 | |
fae3fde6 PZ |
2656 | if (!ctx->is_active) |
2657 | return; | |
2658 | ||
e5d1367f | 2659 | if (!event_filter_match(event)) { |
bd2afa49 | 2660 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2661 | return; |
e5d1367f | 2662 | } |
f4c4176f | 2663 | |
04289bb9 | 2664 | /* |
cdd6c482 | 2665 | * If the event is in a group and isn't the group leader, |
d859e29f | 2666 | * then don't put it on unless the group is on. |
04289bb9 | 2667 | */ |
bd2afa49 PZ |
2668 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2669 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2670 | return; |
bd2afa49 | 2671 | } |
fe4b04fa | 2672 | |
fae3fde6 PZ |
2673 | task_ctx = cpuctx->task_ctx; |
2674 | if (ctx->task) | |
2675 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2676 | |
487f05e1 | 2677 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2678 | } |
2679 | ||
d859e29f | 2680 | /* |
788faab7 | 2681 | * Enable an event. |
c93f7669 | 2682 | * |
cdd6c482 IM |
2683 | * If event->ctx is a cloned context, callers must make sure that |
2684 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2685 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2686 | * perf_event_for_each_child or perf_event_for_each as described |
2687 | * for perf_event_disable. | |
d859e29f | 2688 | */ |
f63a8daa | 2689 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2690 | { |
cdd6c482 | 2691 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2692 | |
7b648018 | 2693 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2694 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2695 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2696 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2697 | return; |
2698 | } | |
2699 | ||
d859e29f | 2700 | /* |
cdd6c482 | 2701 | * If the event is in error state, clear that first. |
7b648018 PZ |
2702 | * |
2703 | * That way, if we see the event in error state below, we know that it | |
2704 | * has gone back into error state, as distinct from the task having | |
2705 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2706 | */ |
cdd6c482 IM |
2707 | if (event->state == PERF_EVENT_STATE_ERROR) |
2708 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2709 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2710 | |
fae3fde6 | 2711 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2712 | } |
f63a8daa PZ |
2713 | |
2714 | /* | |
2715 | * See perf_event_disable(); | |
2716 | */ | |
2717 | void perf_event_enable(struct perf_event *event) | |
2718 | { | |
2719 | struct perf_event_context *ctx; | |
2720 | ||
2721 | ctx = perf_event_ctx_lock(event); | |
2722 | _perf_event_enable(event); | |
2723 | perf_event_ctx_unlock(event, ctx); | |
2724 | } | |
dcfce4a0 | 2725 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2726 | |
375637bc AS |
2727 | struct stop_event_data { |
2728 | struct perf_event *event; | |
2729 | unsigned int restart; | |
2730 | }; | |
2731 | ||
95ff4ca2 AS |
2732 | static int __perf_event_stop(void *info) |
2733 | { | |
375637bc AS |
2734 | struct stop_event_data *sd = info; |
2735 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2736 | |
375637bc | 2737 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2738 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2739 | return 0; | |
2740 | ||
2741 | /* matches smp_wmb() in event_sched_in() */ | |
2742 | smp_rmb(); | |
2743 | ||
2744 | /* | |
2745 | * There is a window with interrupts enabled before we get here, | |
2746 | * so we need to check again lest we try to stop another CPU's event. | |
2747 | */ | |
2748 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2749 | return -EAGAIN; | |
2750 | ||
2751 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2752 | ||
375637bc AS |
2753 | /* |
2754 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2755 | * but it is only used for events with AUX ring buffer, and such | |
2756 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2757 | * see comments in perf_aux_output_begin(). | |
2758 | * | |
788faab7 | 2759 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
2760 | * while restarting. |
2761 | */ | |
2762 | if (sd->restart) | |
c9bbdd48 | 2763 | event->pmu->start(event, 0); |
375637bc | 2764 | |
95ff4ca2 AS |
2765 | return 0; |
2766 | } | |
2767 | ||
767ae086 | 2768 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2769 | { |
2770 | struct stop_event_data sd = { | |
2771 | .event = event, | |
767ae086 | 2772 | .restart = restart, |
375637bc AS |
2773 | }; |
2774 | int ret = 0; | |
2775 | ||
2776 | do { | |
2777 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2778 | return 0; | |
2779 | ||
2780 | /* matches smp_wmb() in event_sched_in() */ | |
2781 | smp_rmb(); | |
2782 | ||
2783 | /* | |
2784 | * We only want to restart ACTIVE events, so if the event goes | |
2785 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2786 | * fall through with ret==-ENXIO. | |
2787 | */ | |
2788 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2789 | __perf_event_stop, &sd); | |
2790 | } while (ret == -EAGAIN); | |
2791 | ||
2792 | return ret; | |
2793 | } | |
2794 | ||
2795 | /* | |
2796 | * In order to contain the amount of racy and tricky in the address filter | |
2797 | * configuration management, it is a two part process: | |
2798 | * | |
2799 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2800 | * we update the addresses of corresponding vmas in | |
2801 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2802 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2803 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2804 | * if the generation has changed since the previous call. | |
2805 | * | |
2806 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2807 | * | |
2808 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2809 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2810 | * ioctl; | |
2811 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2812 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2813 | * for reading; | |
2814 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2815 | * of exec. | |
2816 | */ | |
2817 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2818 | { | |
2819 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2820 | ||
2821 | if (!has_addr_filter(event)) | |
2822 | return; | |
2823 | ||
2824 | raw_spin_lock(&ifh->lock); | |
2825 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2826 | event->pmu->addr_filters_sync(event); | |
2827 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2828 | } | |
2829 | raw_spin_unlock(&ifh->lock); | |
2830 | } | |
2831 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2832 | ||
f63a8daa | 2833 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2834 | { |
2023b359 | 2835 | /* |
cdd6c482 | 2836 | * not supported on inherited events |
2023b359 | 2837 | */ |
2e939d1d | 2838 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2839 | return -EINVAL; |
2840 | ||
cdd6c482 | 2841 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2842 | _perf_event_enable(event); |
2023b359 PZ |
2843 | |
2844 | return 0; | |
79f14641 | 2845 | } |
f63a8daa PZ |
2846 | |
2847 | /* | |
2848 | * See perf_event_disable() | |
2849 | */ | |
2850 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2851 | { | |
2852 | struct perf_event_context *ctx; | |
2853 | int ret; | |
2854 | ||
2855 | ctx = perf_event_ctx_lock(event); | |
2856 | ret = _perf_event_refresh(event, refresh); | |
2857 | perf_event_ctx_unlock(event, ctx); | |
2858 | ||
2859 | return ret; | |
2860 | } | |
26ca5c11 | 2861 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2862 | |
32ff77e8 MC |
2863 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
2864 | struct perf_event_attr *attr) | |
2865 | { | |
2866 | int err; | |
2867 | ||
2868 | _perf_event_disable(bp); | |
2869 | ||
2870 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 2871 | |
bf06278c | 2872 | if (!bp->attr.disabled) |
32ff77e8 | 2873 | _perf_event_enable(bp); |
bf06278c JO |
2874 | |
2875 | return err; | |
32ff77e8 MC |
2876 | } |
2877 | ||
2878 | static int perf_event_modify_attr(struct perf_event *event, | |
2879 | struct perf_event_attr *attr) | |
2880 | { | |
2881 | if (event->attr.type != attr->type) | |
2882 | return -EINVAL; | |
2883 | ||
2884 | switch (event->attr.type) { | |
2885 | case PERF_TYPE_BREAKPOINT: | |
2886 | return perf_event_modify_breakpoint(event, attr); | |
2887 | default: | |
2888 | /* Place holder for future additions. */ | |
2889 | return -EOPNOTSUPP; | |
2890 | } | |
2891 | } | |
2892 | ||
5b0311e1 FW |
2893 | static void ctx_sched_out(struct perf_event_context *ctx, |
2894 | struct perf_cpu_context *cpuctx, | |
2895 | enum event_type_t event_type) | |
235c7fc7 | 2896 | { |
6668128a | 2897 | struct perf_event *event, *tmp; |
db24d33e | 2898 | int is_active = ctx->is_active; |
235c7fc7 | 2899 | |
c994d613 | 2900 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2901 | |
39a43640 PZ |
2902 | if (likely(!ctx->nr_events)) { |
2903 | /* | |
2904 | * See __perf_remove_from_context(). | |
2905 | */ | |
2906 | WARN_ON_ONCE(ctx->is_active); | |
2907 | if (ctx->task) | |
2908 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2909 | return; |
39a43640 PZ |
2910 | } |
2911 | ||
db24d33e | 2912 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2913 | if (!(ctx->is_active & EVENT_ALL)) |
2914 | ctx->is_active = 0; | |
2915 | ||
63e30d3e PZ |
2916 | if (ctx->task) { |
2917 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2918 | if (!ctx->is_active) | |
2919 | cpuctx->task_ctx = NULL; | |
2920 | } | |
facc4307 | 2921 | |
8fdc6539 PZ |
2922 | /* |
2923 | * Always update time if it was set; not only when it changes. | |
2924 | * Otherwise we can 'forget' to update time for any but the last | |
2925 | * context we sched out. For example: | |
2926 | * | |
2927 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2928 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2929 | * | |
2930 | * would only update time for the pinned events. | |
2931 | */ | |
3cbaa590 PZ |
2932 | if (is_active & EVENT_TIME) { |
2933 | /* update (and stop) ctx time */ | |
2934 | update_context_time(ctx); | |
2935 | update_cgrp_time_from_cpuctx(cpuctx); | |
2936 | } | |
2937 | ||
8fdc6539 PZ |
2938 | is_active ^= ctx->is_active; /* changed bits */ |
2939 | ||
3cbaa590 | 2940 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2941 | return; |
5b0311e1 | 2942 | |
075e0b00 | 2943 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2944 | if (is_active & EVENT_PINNED) { |
6668128a | 2945 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 2946 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2947 | } |
889ff015 | 2948 | |
3cbaa590 | 2949 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 2950 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 2951 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2952 | } |
1b9a644f | 2953 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2954 | } |
2955 | ||
564c2b21 | 2956 | /* |
5a3126d4 PZ |
2957 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2958 | * cloned from the same version of the same context. | |
2959 | * | |
2960 | * Equivalence is measured using a generation number in the context that is | |
2961 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2962 | * and list_del_event(). | |
564c2b21 | 2963 | */ |
cdd6c482 IM |
2964 | static int context_equiv(struct perf_event_context *ctx1, |
2965 | struct perf_event_context *ctx2) | |
564c2b21 | 2966 | { |
211de6eb PZ |
2967 | lockdep_assert_held(&ctx1->lock); |
2968 | lockdep_assert_held(&ctx2->lock); | |
2969 | ||
5a3126d4 PZ |
2970 | /* Pinning disables the swap optimization */ |
2971 | if (ctx1->pin_count || ctx2->pin_count) | |
2972 | return 0; | |
2973 | ||
2974 | /* If ctx1 is the parent of ctx2 */ | |
2975 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2976 | return 1; | |
2977 | ||
2978 | /* If ctx2 is the parent of ctx1 */ | |
2979 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2980 | return 1; | |
2981 | ||
2982 | /* | |
2983 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2984 | * hierarchy, see perf_event_init_context(). | |
2985 | */ | |
2986 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2987 | ctx1->parent_gen == ctx2->parent_gen) | |
2988 | return 1; | |
2989 | ||
2990 | /* Unmatched */ | |
2991 | return 0; | |
564c2b21 PM |
2992 | } |
2993 | ||
cdd6c482 IM |
2994 | static void __perf_event_sync_stat(struct perf_event *event, |
2995 | struct perf_event *next_event) | |
bfbd3381 PZ |
2996 | { |
2997 | u64 value; | |
2998 | ||
cdd6c482 | 2999 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3000 | return; |
3001 | ||
3002 | /* | |
cdd6c482 | 3003 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3004 | * because we're in the middle of a context switch and have IRQs |
3005 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3006 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3007 | * don't need to use it. |
3008 | */ | |
0d3d73aa | 3009 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3010 | event->pmu->read(event); |
bfbd3381 | 3011 | |
0d3d73aa | 3012 | perf_event_update_time(event); |
bfbd3381 PZ |
3013 | |
3014 | /* | |
cdd6c482 | 3015 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3016 | * values when we flip the contexts. |
3017 | */ | |
e7850595 PZ |
3018 | value = local64_read(&next_event->count); |
3019 | value = local64_xchg(&event->count, value); | |
3020 | local64_set(&next_event->count, value); | |
bfbd3381 | 3021 | |
cdd6c482 IM |
3022 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3023 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3024 | |
bfbd3381 | 3025 | /* |
19d2e755 | 3026 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3027 | */ |
cdd6c482 IM |
3028 | perf_event_update_userpage(event); |
3029 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3030 | } |
3031 | ||
cdd6c482 IM |
3032 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3033 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3034 | { |
cdd6c482 | 3035 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3036 | |
3037 | if (!ctx->nr_stat) | |
3038 | return; | |
3039 | ||
02ffdbc8 PZ |
3040 | update_context_time(ctx); |
3041 | ||
cdd6c482 IM |
3042 | event = list_first_entry(&ctx->event_list, |
3043 | struct perf_event, event_entry); | |
bfbd3381 | 3044 | |
cdd6c482 IM |
3045 | next_event = list_first_entry(&next_ctx->event_list, |
3046 | struct perf_event, event_entry); | |
bfbd3381 | 3047 | |
cdd6c482 IM |
3048 | while (&event->event_entry != &ctx->event_list && |
3049 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3050 | |
cdd6c482 | 3051 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3052 | |
cdd6c482 IM |
3053 | event = list_next_entry(event, event_entry); |
3054 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3055 | } |
3056 | } | |
3057 | ||
fe4b04fa PZ |
3058 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3059 | struct task_struct *next) | |
0793a61d | 3060 | { |
8dc85d54 | 3061 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3062 | struct perf_event_context *next_ctx; |
5a3126d4 | 3063 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3064 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3065 | int do_switch = 1; |
0793a61d | 3066 | |
108b02cf PZ |
3067 | if (likely(!ctx)) |
3068 | return; | |
10989fb2 | 3069 | |
108b02cf PZ |
3070 | cpuctx = __get_cpu_context(ctx); |
3071 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3072 | return; |
3073 | ||
c93f7669 | 3074 | rcu_read_lock(); |
8dc85d54 | 3075 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3076 | if (!next_ctx) |
3077 | goto unlock; | |
3078 | ||
3079 | parent = rcu_dereference(ctx->parent_ctx); | |
3080 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3081 | ||
3082 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3083 | if (!parent && !next_parent) |
5a3126d4 PZ |
3084 | goto unlock; |
3085 | ||
3086 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3087 | /* |
3088 | * Looks like the two contexts are clones, so we might be | |
3089 | * able to optimize the context switch. We lock both | |
3090 | * contexts and check that they are clones under the | |
3091 | * lock (including re-checking that neither has been | |
3092 | * uncloned in the meantime). It doesn't matter which | |
3093 | * order we take the locks because no other cpu could | |
3094 | * be trying to lock both of these tasks. | |
3095 | */ | |
e625cce1 TG |
3096 | raw_spin_lock(&ctx->lock); |
3097 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3098 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
3099 | WRITE_ONCE(ctx->task, next); |
3100 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
3101 | |
3102 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
3103 | ||
63b6da39 PZ |
3104 | /* |
3105 | * RCU_INIT_POINTER here is safe because we've not | |
3106 | * modified the ctx and the above modification of | |
3107 | * ctx->task and ctx->task_ctx_data are immaterial | |
3108 | * since those values are always verified under | |
3109 | * ctx->lock which we're now holding. | |
3110 | */ | |
3111 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3112 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3113 | ||
c93f7669 | 3114 | do_switch = 0; |
bfbd3381 | 3115 | |
cdd6c482 | 3116 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3117 | } |
e625cce1 TG |
3118 | raw_spin_unlock(&next_ctx->lock); |
3119 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3120 | } |
5a3126d4 | 3121 | unlock: |
c93f7669 | 3122 | rcu_read_unlock(); |
564c2b21 | 3123 | |
c93f7669 | 3124 | if (do_switch) { |
facc4307 | 3125 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3126 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3127 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3128 | } |
0793a61d TG |
3129 | } |
3130 | ||
e48c1788 PZ |
3131 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3132 | ||
ba532500 YZ |
3133 | void perf_sched_cb_dec(struct pmu *pmu) |
3134 | { | |
e48c1788 PZ |
3135 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3136 | ||
ba532500 | 3137 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3138 | |
3139 | if (!--cpuctx->sched_cb_usage) | |
3140 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3141 | } |
3142 | ||
e48c1788 | 3143 | |
ba532500 YZ |
3144 | void perf_sched_cb_inc(struct pmu *pmu) |
3145 | { | |
e48c1788 PZ |
3146 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3147 | ||
3148 | if (!cpuctx->sched_cb_usage++) | |
3149 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3150 | ||
ba532500 YZ |
3151 | this_cpu_inc(perf_sched_cb_usages); |
3152 | } | |
3153 | ||
3154 | /* | |
3155 | * This function provides the context switch callback to the lower code | |
3156 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3157 | * |
3158 | * This callback is relevant even to per-cpu events; for example multi event | |
3159 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3160 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3161 | */ |
3162 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3163 | struct task_struct *next, | |
3164 | bool sched_in) | |
3165 | { | |
3166 | struct perf_cpu_context *cpuctx; | |
3167 | struct pmu *pmu; | |
ba532500 YZ |
3168 | |
3169 | if (prev == next) | |
3170 | return; | |
3171 | ||
e48c1788 | 3172 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3173 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3174 | |
e48c1788 PZ |
3175 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3176 | continue; | |
ba532500 | 3177 | |
e48c1788 PZ |
3178 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3179 | perf_pmu_disable(pmu); | |
ba532500 | 3180 | |
e48c1788 | 3181 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3182 | |
e48c1788 PZ |
3183 | perf_pmu_enable(pmu); |
3184 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3185 | } |
ba532500 YZ |
3186 | } |
3187 | ||
45ac1403 AH |
3188 | static void perf_event_switch(struct task_struct *task, |
3189 | struct task_struct *next_prev, bool sched_in); | |
3190 | ||
8dc85d54 PZ |
3191 | #define for_each_task_context_nr(ctxn) \ |
3192 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3193 | ||
3194 | /* | |
3195 | * Called from scheduler to remove the events of the current task, | |
3196 | * with interrupts disabled. | |
3197 | * | |
3198 | * We stop each event and update the event value in event->count. | |
3199 | * | |
3200 | * This does not protect us against NMI, but disable() | |
3201 | * sets the disabled bit in the control field of event _before_ | |
3202 | * accessing the event control register. If a NMI hits, then it will | |
3203 | * not restart the event. | |
3204 | */ | |
ab0cce56 JO |
3205 | void __perf_event_task_sched_out(struct task_struct *task, |
3206 | struct task_struct *next) | |
8dc85d54 PZ |
3207 | { |
3208 | int ctxn; | |
3209 | ||
ba532500 YZ |
3210 | if (__this_cpu_read(perf_sched_cb_usages)) |
3211 | perf_pmu_sched_task(task, next, false); | |
3212 | ||
45ac1403 AH |
3213 | if (atomic_read(&nr_switch_events)) |
3214 | perf_event_switch(task, next, false); | |
3215 | ||
8dc85d54 PZ |
3216 | for_each_task_context_nr(ctxn) |
3217 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3218 | |
3219 | /* | |
3220 | * if cgroup events exist on this CPU, then we need | |
3221 | * to check if we have to switch out PMU state. | |
3222 | * cgroup event are system-wide mode only | |
3223 | */ | |
4a32fea9 | 3224 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3225 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3226 | } |
3227 | ||
5b0311e1 FW |
3228 | /* |
3229 | * Called with IRQs disabled | |
3230 | */ | |
3231 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3232 | enum event_type_t event_type) | |
3233 | { | |
3234 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3235 | } |
3236 | ||
1cac7b1a PZ |
3237 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3238 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3239 | { |
1cac7b1a PZ |
3240 | struct perf_event **evt, *evt1, *evt2; |
3241 | int ret; | |
8e1a2031 | 3242 | |
1cac7b1a PZ |
3243 | evt1 = perf_event_groups_first(groups, -1); |
3244 | evt2 = perf_event_groups_first(groups, cpu); | |
3245 | ||
3246 | while (evt1 || evt2) { | |
3247 | if (evt1 && evt2) { | |
3248 | if (evt1->group_index < evt2->group_index) | |
3249 | evt = &evt1; | |
3250 | else | |
3251 | evt = &evt2; | |
3252 | } else if (evt1) { | |
3253 | evt = &evt1; | |
3254 | } else { | |
3255 | evt = &evt2; | |
8e1a2031 | 3256 | } |
1cac7b1a PZ |
3257 | |
3258 | ret = func(*evt, data); | |
3259 | if (ret) | |
3260 | return ret; | |
3261 | ||
3262 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3263 | } |
0793a61d | 3264 | |
1cac7b1a PZ |
3265 | return 0; |
3266 | } | |
3267 | ||
3268 | struct sched_in_data { | |
3269 | struct perf_event_context *ctx; | |
3270 | struct perf_cpu_context *cpuctx; | |
3271 | int can_add_hw; | |
3272 | }; | |
3273 | ||
3274 | static int pinned_sched_in(struct perf_event *event, void *data) | |
3275 | { | |
3276 | struct sched_in_data *sid = data; | |
3277 | ||
3278 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3279 | return 0; | |
3280 | ||
3281 | if (!event_filter_match(event)) | |
3282 | return 0; | |
3283 | ||
6668128a PZ |
3284 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3285 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
3286 | list_add_tail(&event->active_list, &sid->ctx->pinned_active); | |
3287 | } | |
1cac7b1a PZ |
3288 | |
3289 | /* | |
3290 | * If this pinned group hasn't been scheduled, | |
3291 | * put it in error state. | |
3292 | */ | |
3293 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
3294 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3295 | ||
3296 | return 0; | |
3297 | } | |
3298 | ||
3299 | static int flexible_sched_in(struct perf_event *event, void *data) | |
3300 | { | |
3301 | struct sched_in_data *sid = data; | |
3302 | ||
3303 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3304 | return 0; | |
3305 | ||
3306 | if (!event_filter_match(event)) | |
3307 | return 0; | |
3308 | ||
3309 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { | |
6668128a PZ |
3310 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) |
3311 | list_add_tail(&event->active_list, &sid->ctx->flexible_active); | |
3312 | else | |
1cac7b1a | 3313 | sid->can_add_hw = 0; |
3b6f9e5c | 3314 | } |
1cac7b1a PZ |
3315 | |
3316 | return 0; | |
5b0311e1 FW |
3317 | } |
3318 | ||
3319 | static void | |
1cac7b1a PZ |
3320 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3321 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3322 | { |
1cac7b1a PZ |
3323 | struct sched_in_data sid = { |
3324 | .ctx = ctx, | |
3325 | .cpuctx = cpuctx, | |
3326 | .can_add_hw = 1, | |
3327 | }; | |
3b6f9e5c | 3328 | |
1cac7b1a PZ |
3329 | visit_groups_merge(&ctx->pinned_groups, |
3330 | smp_processor_id(), | |
3331 | pinned_sched_in, &sid); | |
3332 | } | |
8e1a2031 | 3333 | |
1cac7b1a PZ |
3334 | static void |
3335 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3336 | struct perf_cpu_context *cpuctx) | |
3337 | { | |
3338 | struct sched_in_data sid = { | |
3339 | .ctx = ctx, | |
3340 | .cpuctx = cpuctx, | |
3341 | .can_add_hw = 1, | |
3342 | }; | |
0793a61d | 3343 | |
1cac7b1a PZ |
3344 | visit_groups_merge(&ctx->flexible_groups, |
3345 | smp_processor_id(), | |
3346 | flexible_sched_in, &sid); | |
5b0311e1 FW |
3347 | } |
3348 | ||
3349 | static void | |
3350 | ctx_sched_in(struct perf_event_context *ctx, | |
3351 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3352 | enum event_type_t event_type, |
3353 | struct task_struct *task) | |
5b0311e1 | 3354 | { |
db24d33e | 3355 | int is_active = ctx->is_active; |
c994d613 PZ |
3356 | u64 now; |
3357 | ||
3358 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3359 | |
5b0311e1 | 3360 | if (likely(!ctx->nr_events)) |
facc4307 | 3361 | return; |
5b0311e1 | 3362 | |
3cbaa590 | 3363 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3364 | if (ctx->task) { |
3365 | if (!is_active) | |
3366 | cpuctx->task_ctx = ctx; | |
3367 | else | |
3368 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3369 | } | |
3370 | ||
3cbaa590 PZ |
3371 | is_active ^= ctx->is_active; /* changed bits */ |
3372 | ||
3373 | if (is_active & EVENT_TIME) { | |
3374 | /* start ctx time */ | |
3375 | now = perf_clock(); | |
3376 | ctx->timestamp = now; | |
3377 | perf_cgroup_set_timestamp(task, ctx); | |
3378 | } | |
3379 | ||
5b0311e1 FW |
3380 | /* |
3381 | * First go through the list and put on any pinned groups | |
3382 | * in order to give them the best chance of going on. | |
3383 | */ | |
3cbaa590 | 3384 | if (is_active & EVENT_PINNED) |
6e37738a | 3385 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3386 | |
3387 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3388 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3389 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3390 | } |
3391 | ||
329c0e01 | 3392 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3393 | enum event_type_t event_type, |
3394 | struct task_struct *task) | |
329c0e01 FW |
3395 | { |
3396 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3397 | ||
e5d1367f | 3398 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3399 | } |
3400 | ||
e5d1367f SE |
3401 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3402 | struct task_struct *task) | |
235c7fc7 | 3403 | { |
108b02cf | 3404 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3405 | |
108b02cf | 3406 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3407 | if (cpuctx->task_ctx == ctx) |
3408 | return; | |
3409 | ||
facc4307 | 3410 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3411 | /* |
3412 | * We must check ctx->nr_events while holding ctx->lock, such | |
3413 | * that we serialize against perf_install_in_context(). | |
3414 | */ | |
3415 | if (!ctx->nr_events) | |
3416 | goto unlock; | |
3417 | ||
1b9a644f | 3418 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3419 | /* |
3420 | * We want to keep the following priority order: | |
3421 | * cpu pinned (that don't need to move), task pinned, | |
3422 | * cpu flexible, task flexible. | |
fe45bafb AS |
3423 | * |
3424 | * However, if task's ctx is not carrying any pinned | |
3425 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3426 | */ |
8e1a2031 | 3427 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3428 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3429 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3430 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3431 | |
3432 | unlock: | |
facc4307 | 3433 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3434 | } |
3435 | ||
8dc85d54 PZ |
3436 | /* |
3437 | * Called from scheduler to add the events of the current task | |
3438 | * with interrupts disabled. | |
3439 | * | |
3440 | * We restore the event value and then enable it. | |
3441 | * | |
3442 | * This does not protect us against NMI, but enable() | |
3443 | * sets the enabled bit in the control field of event _before_ | |
3444 | * accessing the event control register. If a NMI hits, then it will | |
3445 | * keep the event running. | |
3446 | */ | |
ab0cce56 JO |
3447 | void __perf_event_task_sched_in(struct task_struct *prev, |
3448 | struct task_struct *task) | |
8dc85d54 PZ |
3449 | { |
3450 | struct perf_event_context *ctx; | |
3451 | int ctxn; | |
3452 | ||
7e41d177 PZ |
3453 | /* |
3454 | * If cgroup events exist on this CPU, then we need to check if we have | |
3455 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3456 | * | |
3457 | * Since cgroup events are CPU events, we must schedule these in before | |
3458 | * we schedule in the task events. | |
3459 | */ | |
3460 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3461 | perf_cgroup_sched_in(prev, task); | |
3462 | ||
8dc85d54 PZ |
3463 | for_each_task_context_nr(ctxn) { |
3464 | ctx = task->perf_event_ctxp[ctxn]; | |
3465 | if (likely(!ctx)) | |
3466 | continue; | |
3467 | ||
e5d1367f | 3468 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3469 | } |
d010b332 | 3470 | |
45ac1403 AH |
3471 | if (atomic_read(&nr_switch_events)) |
3472 | perf_event_switch(task, prev, true); | |
3473 | ||
ba532500 YZ |
3474 | if (__this_cpu_read(perf_sched_cb_usages)) |
3475 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3476 | } |
3477 | ||
abd50713 PZ |
3478 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3479 | { | |
3480 | u64 frequency = event->attr.sample_freq; | |
3481 | u64 sec = NSEC_PER_SEC; | |
3482 | u64 divisor, dividend; | |
3483 | ||
3484 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3485 | ||
3486 | count_fls = fls64(count); | |
3487 | nsec_fls = fls64(nsec); | |
3488 | frequency_fls = fls64(frequency); | |
3489 | sec_fls = 30; | |
3490 | ||
3491 | /* | |
3492 | * We got @count in @nsec, with a target of sample_freq HZ | |
3493 | * the target period becomes: | |
3494 | * | |
3495 | * @count * 10^9 | |
3496 | * period = ------------------- | |
3497 | * @nsec * sample_freq | |
3498 | * | |
3499 | */ | |
3500 | ||
3501 | /* | |
3502 | * Reduce accuracy by one bit such that @a and @b converge | |
3503 | * to a similar magnitude. | |
3504 | */ | |
fe4b04fa | 3505 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3506 | do { \ |
3507 | if (a##_fls > b##_fls) { \ | |
3508 | a >>= 1; \ | |
3509 | a##_fls--; \ | |
3510 | } else { \ | |
3511 | b >>= 1; \ | |
3512 | b##_fls--; \ | |
3513 | } \ | |
3514 | } while (0) | |
3515 | ||
3516 | /* | |
3517 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3518 | * the other, so that finally we can do a u64/u64 division. | |
3519 | */ | |
3520 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3521 | REDUCE_FLS(nsec, frequency); | |
3522 | REDUCE_FLS(sec, count); | |
3523 | } | |
3524 | ||
3525 | if (count_fls + sec_fls > 64) { | |
3526 | divisor = nsec * frequency; | |
3527 | ||
3528 | while (count_fls + sec_fls > 64) { | |
3529 | REDUCE_FLS(count, sec); | |
3530 | divisor >>= 1; | |
3531 | } | |
3532 | ||
3533 | dividend = count * sec; | |
3534 | } else { | |
3535 | dividend = count * sec; | |
3536 | ||
3537 | while (nsec_fls + frequency_fls > 64) { | |
3538 | REDUCE_FLS(nsec, frequency); | |
3539 | dividend >>= 1; | |
3540 | } | |
3541 | ||
3542 | divisor = nsec * frequency; | |
3543 | } | |
3544 | ||
f6ab91ad PZ |
3545 | if (!divisor) |
3546 | return dividend; | |
3547 | ||
abd50713 PZ |
3548 | return div64_u64(dividend, divisor); |
3549 | } | |
3550 | ||
e050e3f0 SE |
3551 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3552 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3553 | ||
f39d47ff | 3554 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3555 | { |
cdd6c482 | 3556 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3557 | s64 period, sample_period; |
bd2b5b12 PZ |
3558 | s64 delta; |
3559 | ||
abd50713 | 3560 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3561 | |
3562 | delta = (s64)(period - hwc->sample_period); | |
3563 | delta = (delta + 7) / 8; /* low pass filter */ | |
3564 | ||
3565 | sample_period = hwc->sample_period + delta; | |
3566 | ||
3567 | if (!sample_period) | |
3568 | sample_period = 1; | |
3569 | ||
bd2b5b12 | 3570 | hwc->sample_period = sample_period; |
abd50713 | 3571 | |
e7850595 | 3572 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3573 | if (disable) |
3574 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3575 | ||
e7850595 | 3576 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3577 | |
3578 | if (disable) | |
3579 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3580 | } |
bd2b5b12 PZ |
3581 | } |
3582 | ||
e050e3f0 SE |
3583 | /* |
3584 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3585 | * events. At the same time, make sure, having freq events does not change | |
3586 | * the rate of unthrottling as that would introduce bias. | |
3587 | */ | |
3588 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3589 | int needs_unthr) | |
60db5e09 | 3590 | { |
cdd6c482 IM |
3591 | struct perf_event *event; |
3592 | struct hw_perf_event *hwc; | |
e050e3f0 | 3593 | u64 now, period = TICK_NSEC; |
abd50713 | 3594 | s64 delta; |
60db5e09 | 3595 | |
e050e3f0 SE |
3596 | /* |
3597 | * only need to iterate over all events iff: | |
3598 | * - context have events in frequency mode (needs freq adjust) | |
3599 | * - there are events to unthrottle on this cpu | |
3600 | */ | |
3601 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3602 | return; |
3603 | ||
e050e3f0 | 3604 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3605 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3606 | |
03541f8b | 3607 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3608 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3609 | continue; |
3610 | ||
5632ab12 | 3611 | if (!event_filter_match(event)) |
5d27c23d PZ |
3612 | continue; |
3613 | ||
44377277 AS |
3614 | perf_pmu_disable(event->pmu); |
3615 | ||
cdd6c482 | 3616 | hwc = &event->hw; |
6a24ed6c | 3617 | |
ae23bff1 | 3618 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3619 | hwc->interrupts = 0; |
cdd6c482 | 3620 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3621 | event->pmu->start(event, 0); |
a78ac325 PZ |
3622 | } |
3623 | ||
cdd6c482 | 3624 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3625 | goto next; |
60db5e09 | 3626 | |
e050e3f0 SE |
3627 | /* |
3628 | * stop the event and update event->count | |
3629 | */ | |
3630 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3631 | ||
e7850595 | 3632 | now = local64_read(&event->count); |
abd50713 PZ |
3633 | delta = now - hwc->freq_count_stamp; |
3634 | hwc->freq_count_stamp = now; | |
60db5e09 | 3635 | |
e050e3f0 SE |
3636 | /* |
3637 | * restart the event | |
3638 | * reload only if value has changed | |
f39d47ff SE |
3639 | * we have stopped the event so tell that |
3640 | * to perf_adjust_period() to avoid stopping it | |
3641 | * twice. | |
e050e3f0 | 3642 | */ |
abd50713 | 3643 | if (delta > 0) |
f39d47ff | 3644 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3645 | |
3646 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3647 | next: |
3648 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3649 | } |
e050e3f0 | 3650 | |
f39d47ff | 3651 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3652 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3653 | } |
3654 | ||
235c7fc7 | 3655 | /* |
8703a7cf | 3656 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3657 | */ |
8703a7cf | 3658 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3659 | { |
dddd3379 TG |
3660 | /* |
3661 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3662 | * disabled by the inheritance code. | |
3663 | */ | |
8703a7cf PZ |
3664 | if (ctx->rotate_disable) |
3665 | return; | |
8e1a2031 | 3666 | |
8703a7cf PZ |
3667 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3668 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3669 | } |
3670 | ||
8d5bce0c PZ |
3671 | static inline struct perf_event * |
3672 | ctx_first_active(struct perf_event_context *ctx) | |
235c7fc7 | 3673 | { |
8d5bce0c PZ |
3674 | return list_first_entry_or_null(&ctx->flexible_active, |
3675 | struct perf_event, active_list); | |
3676 | } | |
3677 | ||
3678 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
3679 | { | |
3680 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
3681 | bool cpu_rotate = false, task_rotate = false; | |
8dc85d54 | 3682 | struct perf_event_context *ctx = NULL; |
8d5bce0c PZ |
3683 | |
3684 | /* | |
3685 | * Since we run this from IRQ context, nobody can install new | |
3686 | * events, thus the event count values are stable. | |
3687 | */ | |
7fc23a53 | 3688 | |
b5ab4cd5 | 3689 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 | 3690 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
8d5bce0c | 3691 | cpu_rotate = true; |
b5ab4cd5 | 3692 | } |
235c7fc7 | 3693 | |
8dc85d54 | 3694 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3695 | if (ctx && ctx->nr_events) { |
b5ab4cd5 | 3696 | if (ctx->nr_events != ctx->nr_active) |
8d5bce0c | 3697 | task_rotate = true; |
b5ab4cd5 | 3698 | } |
9717e6cd | 3699 | |
8d5bce0c PZ |
3700 | if (!(cpu_rotate || task_rotate)) |
3701 | return false; | |
0f5a2601 | 3702 | |
facc4307 | 3703 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3704 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3705 | |
8d5bce0c PZ |
3706 | if (task_rotate) |
3707 | task_event = ctx_first_active(ctx); | |
3708 | if (cpu_rotate) | |
3709 | cpu_event = ctx_first_active(&cpuctx->ctx); | |
8703a7cf | 3710 | |
8d5bce0c PZ |
3711 | /* |
3712 | * As per the order given at ctx_resched() first 'pop' task flexible | |
3713 | * and then, if needed CPU flexible. | |
3714 | */ | |
3715 | if (task_event || (ctx && cpu_event)) | |
e050e3f0 | 3716 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); |
8d5bce0c PZ |
3717 | if (cpu_event) |
3718 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3719 | |
8d5bce0c PZ |
3720 | if (task_event) |
3721 | rotate_ctx(ctx, task_event); | |
3722 | if (cpu_event) | |
3723 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 3724 | |
e050e3f0 | 3725 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3726 | |
0f5a2601 PZ |
3727 | perf_pmu_enable(cpuctx->ctx.pmu); |
3728 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 3729 | |
8d5bce0c | 3730 | return true; |
e9d2b064 PZ |
3731 | } |
3732 | ||
3733 | void perf_event_task_tick(void) | |
3734 | { | |
2fde4f94 MR |
3735 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3736 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3737 | int throttled; |
b5ab4cd5 | 3738 | |
16444645 | 3739 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3740 | |
e050e3f0 SE |
3741 | __this_cpu_inc(perf_throttled_seq); |
3742 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3743 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3744 | |
2fde4f94 | 3745 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3746 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3747 | } |
3748 | ||
889ff015 FW |
3749 | static int event_enable_on_exec(struct perf_event *event, |
3750 | struct perf_event_context *ctx) | |
3751 | { | |
3752 | if (!event->attr.enable_on_exec) | |
3753 | return 0; | |
3754 | ||
3755 | event->attr.enable_on_exec = 0; | |
3756 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3757 | return 0; | |
3758 | ||
0d3d73aa | 3759 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3760 | |
3761 | return 1; | |
3762 | } | |
3763 | ||
57e7986e | 3764 | /* |
cdd6c482 | 3765 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3766 | * This expects task == current. |
3767 | */ | |
c1274499 | 3768 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3769 | { |
c1274499 | 3770 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3771 | enum event_type_t event_type = 0; |
3e349507 | 3772 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3773 | struct perf_event *event; |
57e7986e PM |
3774 | unsigned long flags; |
3775 | int enabled = 0; | |
3776 | ||
3777 | local_irq_save(flags); | |
c1274499 | 3778 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3779 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3780 | goto out; |
3781 | ||
3e349507 PZ |
3782 | cpuctx = __get_cpu_context(ctx); |
3783 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3784 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3785 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3786 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3787 | event_type |= get_event_type(event); |
3788 | } | |
57e7986e PM |
3789 | |
3790 | /* | |
3e349507 | 3791 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3792 | */ |
3e349507 | 3793 | if (enabled) { |
211de6eb | 3794 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3795 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3796 | } else { |
3797 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3798 | } |
3799 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3800 | |
9ed6060d | 3801 | out: |
57e7986e | 3802 | local_irq_restore(flags); |
211de6eb PZ |
3803 | |
3804 | if (clone_ctx) | |
3805 | put_ctx(clone_ctx); | |
57e7986e PM |
3806 | } |
3807 | ||
0492d4c5 PZ |
3808 | struct perf_read_data { |
3809 | struct perf_event *event; | |
3810 | bool group; | |
7d88962e | 3811 | int ret; |
0492d4c5 PZ |
3812 | }; |
3813 | ||
451d24d1 | 3814 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3815 | { |
d6a2f903 DCC |
3816 | u16 local_pkg, event_pkg; |
3817 | ||
3818 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3819 | int local_cpu = smp_processor_id(); |
3820 | ||
3821 | event_pkg = topology_physical_package_id(event_cpu); | |
3822 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3823 | |
3824 | if (event_pkg == local_pkg) | |
3825 | return local_cpu; | |
3826 | } | |
3827 | ||
3828 | return event_cpu; | |
3829 | } | |
3830 | ||
0793a61d | 3831 | /* |
cdd6c482 | 3832 | * Cross CPU call to read the hardware event |
0793a61d | 3833 | */ |
cdd6c482 | 3834 | static void __perf_event_read(void *info) |
0793a61d | 3835 | { |
0492d4c5 PZ |
3836 | struct perf_read_data *data = info; |
3837 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3838 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3839 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3840 | struct pmu *pmu = event->pmu; |
621a01ea | 3841 | |
e1ac3614 PM |
3842 | /* |
3843 | * If this is a task context, we need to check whether it is | |
3844 | * the current task context of this cpu. If not it has been | |
3845 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3846 | * event->count would have been updated to a recent sample |
3847 | * when the event was scheduled out. | |
e1ac3614 PM |
3848 | */ |
3849 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3850 | return; | |
3851 | ||
e625cce1 | 3852 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3853 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 3854 | update_context_time(ctx); |
e5d1367f SE |
3855 | update_cgrp_time_from_event(event); |
3856 | } | |
0492d4c5 | 3857 | |
0d3d73aa PZ |
3858 | perf_event_update_time(event); |
3859 | if (data->group) | |
3860 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 3861 | |
4a00c16e SB |
3862 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3863 | goto unlock; | |
0492d4c5 | 3864 | |
4a00c16e SB |
3865 | if (!data->group) { |
3866 | pmu->read(event); | |
3867 | data->ret = 0; | |
0492d4c5 | 3868 | goto unlock; |
4a00c16e SB |
3869 | } |
3870 | ||
3871 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3872 | ||
3873 | pmu->read(event); | |
0492d4c5 | 3874 | |
edb39592 | 3875 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
3876 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3877 | /* | |
3878 | * Use sibling's PMU rather than @event's since | |
3879 | * sibling could be on different (eg: software) PMU. | |
3880 | */ | |
0492d4c5 | 3881 | sub->pmu->read(sub); |
4a00c16e | 3882 | } |
0492d4c5 | 3883 | } |
4a00c16e SB |
3884 | |
3885 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3886 | |
3887 | unlock: | |
e625cce1 | 3888 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3889 | } |
3890 | ||
b5e58793 PZ |
3891 | static inline u64 perf_event_count(struct perf_event *event) |
3892 | { | |
c39a0e2c | 3893 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
3894 | } |
3895 | ||
ffe8690c KX |
3896 | /* |
3897 | * NMI-safe method to read a local event, that is an event that | |
3898 | * is: | |
3899 | * - either for the current task, or for this CPU | |
3900 | * - does not have inherit set, for inherited task events | |
3901 | * will not be local and we cannot read them atomically | |
3902 | * - must not have a pmu::count method | |
3903 | */ | |
7d9285e8 YS |
3904 | int perf_event_read_local(struct perf_event *event, u64 *value, |
3905 | u64 *enabled, u64 *running) | |
ffe8690c KX |
3906 | { |
3907 | unsigned long flags; | |
f91840a3 | 3908 | int ret = 0; |
ffe8690c KX |
3909 | |
3910 | /* | |
3911 | * Disabling interrupts avoids all counter scheduling (context | |
3912 | * switches, timer based rotation and IPIs). | |
3913 | */ | |
3914 | local_irq_save(flags); | |
3915 | ||
ffe8690c KX |
3916 | /* |
3917 | * It must not be an event with inherit set, we cannot read | |
3918 | * all child counters from atomic context. | |
3919 | */ | |
f91840a3 AS |
3920 | if (event->attr.inherit) { |
3921 | ret = -EOPNOTSUPP; | |
3922 | goto out; | |
3923 | } | |
ffe8690c | 3924 | |
f91840a3 AS |
3925 | /* If this is a per-task event, it must be for current */ |
3926 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
3927 | event->hw.target != current) { | |
3928 | ret = -EINVAL; | |
3929 | goto out; | |
3930 | } | |
3931 | ||
3932 | /* If this is a per-CPU event, it must be for this CPU */ | |
3933 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
3934 | event->cpu != smp_processor_id()) { | |
3935 | ret = -EINVAL; | |
3936 | goto out; | |
3937 | } | |
ffe8690c | 3938 | |
befb1b3c RC |
3939 | /* If this is a pinned event it must be running on this CPU */ |
3940 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
3941 | ret = -EBUSY; | |
3942 | goto out; | |
3943 | } | |
3944 | ||
ffe8690c KX |
3945 | /* |
3946 | * If the event is currently on this CPU, its either a per-task event, | |
3947 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3948 | * oncpu == -1). | |
3949 | */ | |
3950 | if (event->oncpu == smp_processor_id()) | |
3951 | event->pmu->read(event); | |
3952 | ||
f91840a3 | 3953 | *value = local64_read(&event->count); |
0d3d73aa PZ |
3954 | if (enabled || running) { |
3955 | u64 now = event->shadow_ctx_time + perf_clock(); | |
3956 | u64 __enabled, __running; | |
3957 | ||
3958 | __perf_update_times(event, now, &__enabled, &__running); | |
3959 | if (enabled) | |
3960 | *enabled = __enabled; | |
3961 | if (running) | |
3962 | *running = __running; | |
3963 | } | |
f91840a3 | 3964 | out: |
ffe8690c KX |
3965 | local_irq_restore(flags); |
3966 | ||
f91840a3 | 3967 | return ret; |
ffe8690c KX |
3968 | } |
3969 | ||
7d88962e | 3970 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3971 | { |
0c1cbc18 | 3972 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 3973 | int event_cpu, ret = 0; |
7d88962e | 3974 | |
0793a61d | 3975 | /* |
cdd6c482 IM |
3976 | * If event is enabled and currently active on a CPU, update the |
3977 | * value in the event structure: | |
0793a61d | 3978 | */ |
0c1cbc18 PZ |
3979 | again: |
3980 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
3981 | struct perf_read_data data; | |
3982 | ||
3983 | /* | |
3984 | * Orders the ->state and ->oncpu loads such that if we see | |
3985 | * ACTIVE we must also see the right ->oncpu. | |
3986 | * | |
3987 | * Matches the smp_wmb() from event_sched_in(). | |
3988 | */ | |
3989 | smp_rmb(); | |
d6a2f903 | 3990 | |
451d24d1 PZ |
3991 | event_cpu = READ_ONCE(event->oncpu); |
3992 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
3993 | return 0; | |
3994 | ||
0c1cbc18 PZ |
3995 | data = (struct perf_read_data){ |
3996 | .event = event, | |
3997 | .group = group, | |
3998 | .ret = 0, | |
3999 | }; | |
4000 | ||
451d24d1 PZ |
4001 | preempt_disable(); |
4002 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4003 | |
58763148 PZ |
4004 | /* |
4005 | * Purposely ignore the smp_call_function_single() return | |
4006 | * value. | |
4007 | * | |
451d24d1 | 4008 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4009 | * scheduled out and that will have updated the event count. |
4010 | * | |
4011 | * Therefore, either way, we'll have an up-to-date event count | |
4012 | * after this. | |
4013 | */ | |
451d24d1 PZ |
4014 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4015 | preempt_enable(); | |
58763148 | 4016 | ret = data.ret; |
0c1cbc18 PZ |
4017 | |
4018 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4019 | struct perf_event_context *ctx = event->ctx; |
4020 | unsigned long flags; | |
4021 | ||
e625cce1 | 4022 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4023 | state = event->state; |
4024 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4025 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4026 | goto again; | |
4027 | } | |
4028 | ||
c530ccd9 | 4029 | /* |
0c1cbc18 PZ |
4030 | * May read while context is not active (e.g., thread is |
4031 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4032 | */ |
0c1cbc18 | 4033 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4034 | update_context_time(ctx); |
e5d1367f SE |
4035 | update_cgrp_time_from_event(event); |
4036 | } | |
0c1cbc18 | 4037 | |
0d3d73aa | 4038 | perf_event_update_time(event); |
0492d4c5 | 4039 | if (group) |
0d3d73aa | 4040 | perf_event_update_sibling_time(event); |
e625cce1 | 4041 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4042 | } |
7d88962e SB |
4043 | |
4044 | return ret; | |
0793a61d TG |
4045 | } |
4046 | ||
a63eaf34 | 4047 | /* |
cdd6c482 | 4048 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4049 | */ |
eb184479 | 4050 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4051 | { |
e625cce1 | 4052 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4053 | mutex_init(&ctx->mutex); |
2fde4f94 | 4054 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4055 | perf_event_groups_init(&ctx->pinned_groups); |
4056 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4057 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4058 | INIT_LIST_HEAD(&ctx->pinned_active); |
4059 | INIT_LIST_HEAD(&ctx->flexible_active); | |
a63eaf34 | 4060 | atomic_set(&ctx->refcount, 1); |
eb184479 PZ |
4061 | } |
4062 | ||
4063 | static struct perf_event_context * | |
4064 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4065 | { | |
4066 | struct perf_event_context *ctx; | |
4067 | ||
4068 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4069 | if (!ctx) | |
4070 | return NULL; | |
4071 | ||
4072 | __perf_event_init_context(ctx); | |
4073 | if (task) { | |
4074 | ctx->task = task; | |
4075 | get_task_struct(task); | |
0793a61d | 4076 | } |
eb184479 PZ |
4077 | ctx->pmu = pmu; |
4078 | ||
4079 | return ctx; | |
a63eaf34 PM |
4080 | } |
4081 | ||
2ebd4ffb MH |
4082 | static struct task_struct * |
4083 | find_lively_task_by_vpid(pid_t vpid) | |
4084 | { | |
4085 | struct task_struct *task; | |
0793a61d TG |
4086 | |
4087 | rcu_read_lock(); | |
2ebd4ffb | 4088 | if (!vpid) |
0793a61d TG |
4089 | task = current; |
4090 | else | |
2ebd4ffb | 4091 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4092 | if (task) |
4093 | get_task_struct(task); | |
4094 | rcu_read_unlock(); | |
4095 | ||
4096 | if (!task) | |
4097 | return ERR_PTR(-ESRCH); | |
4098 | ||
2ebd4ffb | 4099 | return task; |
2ebd4ffb MH |
4100 | } |
4101 | ||
fe4b04fa PZ |
4102 | /* |
4103 | * Returns a matching context with refcount and pincount. | |
4104 | */ | |
108b02cf | 4105 | static struct perf_event_context * |
4af57ef2 YZ |
4106 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4107 | struct perf_event *event) | |
0793a61d | 4108 | { |
211de6eb | 4109 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4110 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4111 | void *task_ctx_data = NULL; |
25346b93 | 4112 | unsigned long flags; |
8dc85d54 | 4113 | int ctxn, err; |
4af57ef2 | 4114 | int cpu = event->cpu; |
0793a61d | 4115 | |
22a4ec72 | 4116 | if (!task) { |
cdd6c482 | 4117 | /* Must be root to operate on a CPU event: */ |
0764771d | 4118 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
4119 | return ERR_PTR(-EACCES); |
4120 | ||
108b02cf | 4121 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4122 | ctx = &cpuctx->ctx; |
c93f7669 | 4123 | get_ctx(ctx); |
fe4b04fa | 4124 | ++ctx->pin_count; |
0793a61d | 4125 | |
0793a61d TG |
4126 | return ctx; |
4127 | } | |
4128 | ||
8dc85d54 PZ |
4129 | err = -EINVAL; |
4130 | ctxn = pmu->task_ctx_nr; | |
4131 | if (ctxn < 0) | |
4132 | goto errout; | |
4133 | ||
4af57ef2 YZ |
4134 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4135 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4136 | if (!task_ctx_data) { | |
4137 | err = -ENOMEM; | |
4138 | goto errout; | |
4139 | } | |
4140 | } | |
4141 | ||
9ed6060d | 4142 | retry: |
8dc85d54 | 4143 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4144 | if (ctx) { |
211de6eb | 4145 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4146 | ++ctx->pin_count; |
4af57ef2 YZ |
4147 | |
4148 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4149 | ctx->task_ctx_data = task_ctx_data; | |
4150 | task_ctx_data = NULL; | |
4151 | } | |
e625cce1 | 4152 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4153 | |
4154 | if (clone_ctx) | |
4155 | put_ctx(clone_ctx); | |
9137fb28 | 4156 | } else { |
eb184479 | 4157 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4158 | err = -ENOMEM; |
4159 | if (!ctx) | |
4160 | goto errout; | |
eb184479 | 4161 | |
4af57ef2 YZ |
4162 | if (task_ctx_data) { |
4163 | ctx->task_ctx_data = task_ctx_data; | |
4164 | task_ctx_data = NULL; | |
4165 | } | |
4166 | ||
dbe08d82 ON |
4167 | err = 0; |
4168 | mutex_lock(&task->perf_event_mutex); | |
4169 | /* | |
4170 | * If it has already passed perf_event_exit_task(). | |
4171 | * we must see PF_EXITING, it takes this mutex too. | |
4172 | */ | |
4173 | if (task->flags & PF_EXITING) | |
4174 | err = -ESRCH; | |
4175 | else if (task->perf_event_ctxp[ctxn]) | |
4176 | err = -EAGAIN; | |
fe4b04fa | 4177 | else { |
9137fb28 | 4178 | get_ctx(ctx); |
fe4b04fa | 4179 | ++ctx->pin_count; |
dbe08d82 | 4180 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4181 | } |
dbe08d82 ON |
4182 | mutex_unlock(&task->perf_event_mutex); |
4183 | ||
4184 | if (unlikely(err)) { | |
9137fb28 | 4185 | put_ctx(ctx); |
dbe08d82 ON |
4186 | |
4187 | if (err == -EAGAIN) | |
4188 | goto retry; | |
4189 | goto errout; | |
a63eaf34 PM |
4190 | } |
4191 | } | |
4192 | ||
4af57ef2 | 4193 | kfree(task_ctx_data); |
0793a61d | 4194 | return ctx; |
c93f7669 | 4195 | |
9ed6060d | 4196 | errout: |
4af57ef2 | 4197 | kfree(task_ctx_data); |
c93f7669 | 4198 | return ERR_PTR(err); |
0793a61d TG |
4199 | } |
4200 | ||
6fb2915d | 4201 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4202 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4203 | |
cdd6c482 | 4204 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4205 | { |
cdd6c482 | 4206 | struct perf_event *event; |
592903cd | 4207 | |
cdd6c482 IM |
4208 | event = container_of(head, struct perf_event, rcu_head); |
4209 | if (event->ns) | |
4210 | put_pid_ns(event->ns); | |
6fb2915d | 4211 | perf_event_free_filter(event); |
cdd6c482 | 4212 | kfree(event); |
592903cd PZ |
4213 | } |
4214 | ||
b69cf536 PZ |
4215 | static void ring_buffer_attach(struct perf_event *event, |
4216 | struct ring_buffer *rb); | |
925d519a | 4217 | |
f2fb6bef KL |
4218 | static void detach_sb_event(struct perf_event *event) |
4219 | { | |
4220 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4221 | ||
4222 | raw_spin_lock(&pel->lock); | |
4223 | list_del_rcu(&event->sb_list); | |
4224 | raw_spin_unlock(&pel->lock); | |
4225 | } | |
4226 | ||
a4f144eb | 4227 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4228 | { |
a4f144eb DCC |
4229 | struct perf_event_attr *attr = &event->attr; |
4230 | ||
f2fb6bef | 4231 | if (event->parent) |
a4f144eb | 4232 | return false; |
f2fb6bef KL |
4233 | |
4234 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4235 | return false; |
f2fb6bef | 4236 | |
a4f144eb DCC |
4237 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4238 | attr->comm || attr->comm_exec || | |
76193a94 | 4239 | attr->task || attr->ksymbol || |
a4f144eb DCC |
4240 | attr->context_switch) |
4241 | return true; | |
4242 | return false; | |
4243 | } | |
4244 | ||
4245 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4246 | { | |
4247 | if (is_sb_event(event)) | |
4248 | detach_sb_event(event); | |
f2fb6bef KL |
4249 | } |
4250 | ||
4beb31f3 | 4251 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4252 | { |
4beb31f3 FW |
4253 | if (event->parent) |
4254 | return; | |
4255 | ||
4beb31f3 FW |
4256 | if (is_cgroup_event(event)) |
4257 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4258 | } | |
925d519a | 4259 | |
555e0c1e FW |
4260 | #ifdef CONFIG_NO_HZ_FULL |
4261 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4262 | #endif | |
4263 | ||
4264 | static void unaccount_freq_event_nohz(void) | |
4265 | { | |
4266 | #ifdef CONFIG_NO_HZ_FULL | |
4267 | spin_lock(&nr_freq_lock); | |
4268 | if (atomic_dec_and_test(&nr_freq_events)) | |
4269 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4270 | spin_unlock(&nr_freq_lock); | |
4271 | #endif | |
4272 | } | |
4273 | ||
4274 | static void unaccount_freq_event(void) | |
4275 | { | |
4276 | if (tick_nohz_full_enabled()) | |
4277 | unaccount_freq_event_nohz(); | |
4278 | else | |
4279 | atomic_dec(&nr_freq_events); | |
4280 | } | |
4281 | ||
4beb31f3 FW |
4282 | static void unaccount_event(struct perf_event *event) |
4283 | { | |
25432ae9 PZ |
4284 | bool dec = false; |
4285 | ||
4beb31f3 FW |
4286 | if (event->parent) |
4287 | return; | |
4288 | ||
4289 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4290 | dec = true; |
4beb31f3 FW |
4291 | if (event->attr.mmap || event->attr.mmap_data) |
4292 | atomic_dec(&nr_mmap_events); | |
4293 | if (event->attr.comm) | |
4294 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4295 | if (event->attr.namespaces) |
4296 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4297 | if (event->attr.task) |
4298 | atomic_dec(&nr_task_events); | |
948b26b6 | 4299 | if (event->attr.freq) |
555e0c1e | 4300 | unaccount_freq_event(); |
45ac1403 | 4301 | if (event->attr.context_switch) { |
25432ae9 | 4302 | dec = true; |
45ac1403 AH |
4303 | atomic_dec(&nr_switch_events); |
4304 | } | |
4beb31f3 | 4305 | if (is_cgroup_event(event)) |
25432ae9 | 4306 | dec = true; |
4beb31f3 | 4307 | if (has_branch_stack(event)) |
25432ae9 | 4308 | dec = true; |
76193a94 SL |
4309 | if (event->attr.ksymbol) |
4310 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4311 | if (event->attr.bpf_event) |
4312 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4313 | |
9107c89e PZ |
4314 | if (dec) { |
4315 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4316 | schedule_delayed_work(&perf_sched_work, HZ); | |
4317 | } | |
4beb31f3 FW |
4318 | |
4319 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4320 | |
4321 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4322 | } |
925d519a | 4323 | |
9107c89e PZ |
4324 | static void perf_sched_delayed(struct work_struct *work) |
4325 | { | |
4326 | mutex_lock(&perf_sched_mutex); | |
4327 | if (atomic_dec_and_test(&perf_sched_count)) | |
4328 | static_branch_disable(&perf_sched_events); | |
4329 | mutex_unlock(&perf_sched_mutex); | |
4330 | } | |
4331 | ||
bed5b25a AS |
4332 | /* |
4333 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4334 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4335 | * at a time, so we disallow creating events that might conflict, namely: | |
4336 | * | |
4337 | * 1) cpu-wide events in the presence of per-task events, | |
4338 | * 2) per-task events in the presence of cpu-wide events, | |
4339 | * 3) two matching events on the same context. | |
4340 | * | |
4341 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4342 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4343 | */ |
4344 | static int exclusive_event_init(struct perf_event *event) | |
4345 | { | |
4346 | struct pmu *pmu = event->pmu; | |
4347 | ||
4348 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4349 | return 0; | |
4350 | ||
4351 | /* | |
4352 | * Prevent co-existence of per-task and cpu-wide events on the | |
4353 | * same exclusive pmu. | |
4354 | * | |
4355 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4356 | * events on this "exclusive" pmu, positive means there are | |
4357 | * per-task events. | |
4358 | * | |
4359 | * Since this is called in perf_event_alloc() path, event::ctx | |
4360 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4361 | * to mean "per-task event", because unlike other attach states it | |
4362 | * never gets cleared. | |
4363 | */ | |
4364 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4365 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4366 | return -EBUSY; | |
4367 | } else { | |
4368 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4369 | return -EBUSY; | |
4370 | } | |
4371 | ||
4372 | return 0; | |
4373 | } | |
4374 | ||
4375 | static void exclusive_event_destroy(struct perf_event *event) | |
4376 | { | |
4377 | struct pmu *pmu = event->pmu; | |
4378 | ||
4379 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4380 | return; | |
4381 | ||
4382 | /* see comment in exclusive_event_init() */ | |
4383 | if (event->attach_state & PERF_ATTACH_TASK) | |
4384 | atomic_dec(&pmu->exclusive_cnt); | |
4385 | else | |
4386 | atomic_inc(&pmu->exclusive_cnt); | |
4387 | } | |
4388 | ||
4389 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4390 | { | |
3bf6215a | 4391 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4392 | (e1->cpu == e2->cpu || |
4393 | e1->cpu == -1 || | |
4394 | e2->cpu == -1)) | |
4395 | return true; | |
4396 | return false; | |
4397 | } | |
4398 | ||
4399 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4400 | static bool exclusive_event_installable(struct perf_event *event, | |
4401 | struct perf_event_context *ctx) | |
4402 | { | |
4403 | struct perf_event *iter_event; | |
4404 | struct pmu *pmu = event->pmu; | |
4405 | ||
4406 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4407 | return true; | |
4408 | ||
4409 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4410 | if (exclusive_event_match(iter_event, event)) | |
4411 | return false; | |
4412 | } | |
4413 | ||
4414 | return true; | |
4415 | } | |
4416 | ||
375637bc AS |
4417 | static void perf_addr_filters_splice(struct perf_event *event, |
4418 | struct list_head *head); | |
4419 | ||
683ede43 | 4420 | static void _free_event(struct perf_event *event) |
f1600952 | 4421 | { |
e360adbe | 4422 | irq_work_sync(&event->pending); |
925d519a | 4423 | |
4beb31f3 | 4424 | unaccount_event(event); |
9ee318a7 | 4425 | |
76369139 | 4426 | if (event->rb) { |
9bb5d40c PZ |
4427 | /* |
4428 | * Can happen when we close an event with re-directed output. | |
4429 | * | |
4430 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4431 | * over us; possibly making our ring_buffer_put() the last. | |
4432 | */ | |
4433 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4434 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4435 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4436 | } |
4437 | ||
e5d1367f SE |
4438 | if (is_cgroup_event(event)) |
4439 | perf_detach_cgroup(event); | |
4440 | ||
a0733e69 PZ |
4441 | if (!event->parent) { |
4442 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4443 | put_callchain_buffers(); | |
4444 | } | |
4445 | ||
4446 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4447 | perf_addr_filters_splice(event, NULL); |
4448 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4449 | |
4450 | if (event->destroy) | |
4451 | event->destroy(event); | |
4452 | ||
4453 | if (event->ctx) | |
4454 | put_ctx(event->ctx); | |
4455 | ||
621b6d2e PB |
4456 | if (event->hw.target) |
4457 | put_task_struct(event->hw.target); | |
4458 | ||
62a92c8f AS |
4459 | exclusive_event_destroy(event); |
4460 | module_put(event->pmu->module); | |
a0733e69 PZ |
4461 | |
4462 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4463 | } |
4464 | ||
683ede43 PZ |
4465 | /* |
4466 | * Used to free events which have a known refcount of 1, such as in error paths | |
4467 | * where the event isn't exposed yet and inherited events. | |
4468 | */ | |
4469 | static void free_event(struct perf_event *event) | |
0793a61d | 4470 | { |
683ede43 PZ |
4471 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4472 | "unexpected event refcount: %ld; ptr=%p\n", | |
4473 | atomic_long_read(&event->refcount), event)) { | |
4474 | /* leak to avoid use-after-free */ | |
4475 | return; | |
4476 | } | |
0793a61d | 4477 | |
683ede43 | 4478 | _free_event(event); |
0793a61d TG |
4479 | } |
4480 | ||
a66a3052 | 4481 | /* |
f8697762 | 4482 | * Remove user event from the owner task. |
a66a3052 | 4483 | */ |
f8697762 | 4484 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4485 | { |
8882135b | 4486 | struct task_struct *owner; |
fb0459d7 | 4487 | |
8882135b | 4488 | rcu_read_lock(); |
8882135b | 4489 | /* |
f47c02c0 PZ |
4490 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4491 | * observe !owner it means the list deletion is complete and we can | |
4492 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4493 | * owner->perf_event_mutex. |
4494 | */ | |
506458ef | 4495 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4496 | if (owner) { |
4497 | /* | |
4498 | * Since delayed_put_task_struct() also drops the last | |
4499 | * task reference we can safely take a new reference | |
4500 | * while holding the rcu_read_lock(). | |
4501 | */ | |
4502 | get_task_struct(owner); | |
4503 | } | |
4504 | rcu_read_unlock(); | |
4505 | ||
4506 | if (owner) { | |
f63a8daa PZ |
4507 | /* |
4508 | * If we're here through perf_event_exit_task() we're already | |
4509 | * holding ctx->mutex which would be an inversion wrt. the | |
4510 | * normal lock order. | |
4511 | * | |
4512 | * However we can safely take this lock because its the child | |
4513 | * ctx->mutex. | |
4514 | */ | |
4515 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4516 | ||
8882135b PZ |
4517 | /* |
4518 | * We have to re-check the event->owner field, if it is cleared | |
4519 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4520 | * ensured they're done, and we can proceed with freeing the | |
4521 | * event. | |
4522 | */ | |
f47c02c0 | 4523 | if (event->owner) { |
8882135b | 4524 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4525 | smp_store_release(&event->owner, NULL); |
4526 | } | |
8882135b PZ |
4527 | mutex_unlock(&owner->perf_event_mutex); |
4528 | put_task_struct(owner); | |
4529 | } | |
f8697762 JO |
4530 | } |
4531 | ||
f8697762 JO |
4532 | static void put_event(struct perf_event *event) |
4533 | { | |
f8697762 JO |
4534 | if (!atomic_long_dec_and_test(&event->refcount)) |
4535 | return; | |
4536 | ||
c6e5b732 PZ |
4537 | _free_event(event); |
4538 | } | |
4539 | ||
4540 | /* | |
4541 | * Kill an event dead; while event:refcount will preserve the event | |
4542 | * object, it will not preserve its functionality. Once the last 'user' | |
4543 | * gives up the object, we'll destroy the thing. | |
4544 | */ | |
4545 | int perf_event_release_kernel(struct perf_event *event) | |
4546 | { | |
a4f4bb6d | 4547 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4548 | struct perf_event *child, *tmp; |
82d94856 | 4549 | LIST_HEAD(free_list); |
c6e5b732 | 4550 | |
a4f4bb6d PZ |
4551 | /* |
4552 | * If we got here through err_file: fput(event_file); we will not have | |
4553 | * attached to a context yet. | |
4554 | */ | |
4555 | if (!ctx) { | |
4556 | WARN_ON_ONCE(event->attach_state & | |
4557 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4558 | goto no_ctx; | |
4559 | } | |
4560 | ||
f8697762 JO |
4561 | if (!is_kernel_event(event)) |
4562 | perf_remove_from_owner(event); | |
8882135b | 4563 | |
5fa7c8ec | 4564 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4565 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4566 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4567 | |
a69b0ca4 | 4568 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4569 | /* |
d8a8cfc7 | 4570 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4571 | * anymore. |
683ede43 | 4572 | * |
a69b0ca4 PZ |
4573 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4574 | * also see this, most importantly inherit_event() which will avoid | |
4575 | * placing more children on the list. | |
683ede43 | 4576 | * |
c6e5b732 PZ |
4577 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4578 | * child events. | |
683ede43 | 4579 | */ |
a69b0ca4 PZ |
4580 | event->state = PERF_EVENT_STATE_DEAD; |
4581 | raw_spin_unlock_irq(&ctx->lock); | |
4582 | ||
4583 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4584 | |
c6e5b732 PZ |
4585 | again: |
4586 | mutex_lock(&event->child_mutex); | |
4587 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4588 | |
c6e5b732 PZ |
4589 | /* |
4590 | * Cannot change, child events are not migrated, see the | |
4591 | * comment with perf_event_ctx_lock_nested(). | |
4592 | */ | |
506458ef | 4593 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4594 | /* |
4595 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4596 | * through hoops. We start by grabbing a reference on the ctx. | |
4597 | * | |
4598 | * Since the event cannot get freed while we hold the | |
4599 | * child_mutex, the context must also exist and have a !0 | |
4600 | * reference count. | |
4601 | */ | |
4602 | get_ctx(ctx); | |
4603 | ||
4604 | /* | |
4605 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4606 | * acquire ctx::mutex without fear of it going away. Then we | |
4607 | * can re-acquire child_mutex. | |
4608 | */ | |
4609 | mutex_unlock(&event->child_mutex); | |
4610 | mutex_lock(&ctx->mutex); | |
4611 | mutex_lock(&event->child_mutex); | |
4612 | ||
4613 | /* | |
4614 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4615 | * state, if child is still the first entry, it didn't get freed | |
4616 | * and we can continue doing so. | |
4617 | */ | |
4618 | tmp = list_first_entry_or_null(&event->child_list, | |
4619 | struct perf_event, child_list); | |
4620 | if (tmp == child) { | |
4621 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4622 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4623 | /* |
4624 | * This matches the refcount bump in inherit_event(); | |
4625 | * this can't be the last reference. | |
4626 | */ | |
4627 | put_event(event); | |
4628 | } | |
4629 | ||
4630 | mutex_unlock(&event->child_mutex); | |
4631 | mutex_unlock(&ctx->mutex); | |
4632 | put_ctx(ctx); | |
4633 | goto again; | |
4634 | } | |
4635 | mutex_unlock(&event->child_mutex); | |
4636 | ||
82d94856 PZ |
4637 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
4638 | list_del(&child->child_list); | |
4639 | free_event(child); | |
4640 | } | |
4641 | ||
a4f4bb6d PZ |
4642 | no_ctx: |
4643 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4644 | return 0; |
4645 | } | |
4646 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4647 | ||
8b10c5e2 PZ |
4648 | /* |
4649 | * Called when the last reference to the file is gone. | |
4650 | */ | |
a6fa941d AV |
4651 | static int perf_release(struct inode *inode, struct file *file) |
4652 | { | |
c6e5b732 | 4653 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4654 | return 0; |
fb0459d7 | 4655 | } |
fb0459d7 | 4656 | |
ca0dd44c | 4657 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4658 | { |
cdd6c482 | 4659 | struct perf_event *child; |
e53c0994 PZ |
4660 | u64 total = 0; |
4661 | ||
59ed446f PZ |
4662 | *enabled = 0; |
4663 | *running = 0; | |
4664 | ||
6f10581a | 4665 | mutex_lock(&event->child_mutex); |
01add3ea | 4666 | |
7d88962e | 4667 | (void)perf_event_read(event, false); |
01add3ea SB |
4668 | total += perf_event_count(event); |
4669 | ||
59ed446f PZ |
4670 | *enabled += event->total_time_enabled + |
4671 | atomic64_read(&event->child_total_time_enabled); | |
4672 | *running += event->total_time_running + | |
4673 | atomic64_read(&event->child_total_time_running); | |
4674 | ||
4675 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4676 | (void)perf_event_read(child, false); |
01add3ea | 4677 | total += perf_event_count(child); |
59ed446f PZ |
4678 | *enabled += child->total_time_enabled; |
4679 | *running += child->total_time_running; | |
4680 | } | |
6f10581a | 4681 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4682 | |
4683 | return total; | |
4684 | } | |
ca0dd44c PZ |
4685 | |
4686 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4687 | { | |
4688 | struct perf_event_context *ctx; | |
4689 | u64 count; | |
4690 | ||
4691 | ctx = perf_event_ctx_lock(event); | |
4692 | count = __perf_event_read_value(event, enabled, running); | |
4693 | perf_event_ctx_unlock(event, ctx); | |
4694 | ||
4695 | return count; | |
4696 | } | |
fb0459d7 | 4697 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4698 | |
7d88962e | 4699 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4700 | u64 read_format, u64 *values) |
3dab77fb | 4701 | { |
2aeb1883 | 4702 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4703 | struct perf_event *sub; |
2aeb1883 | 4704 | unsigned long flags; |
fa8c2693 | 4705 | int n = 1; /* skip @nr */ |
7d88962e | 4706 | int ret; |
f63a8daa | 4707 | |
7d88962e SB |
4708 | ret = perf_event_read(leader, true); |
4709 | if (ret) | |
4710 | return ret; | |
abf4868b | 4711 | |
a9cd8194 PZ |
4712 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4713 | ||
fa8c2693 PZ |
4714 | /* |
4715 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4716 | * will be identical to those of the leader, so we only publish one | |
4717 | * set. | |
4718 | */ | |
4719 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4720 | values[n++] += leader->total_time_enabled + | |
4721 | atomic64_read(&leader->child_total_time_enabled); | |
4722 | } | |
3dab77fb | 4723 | |
fa8c2693 PZ |
4724 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4725 | values[n++] += leader->total_time_running + | |
4726 | atomic64_read(&leader->child_total_time_running); | |
4727 | } | |
4728 | ||
4729 | /* | |
4730 | * Write {count,id} tuples for every sibling. | |
4731 | */ | |
4732 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4733 | if (read_format & PERF_FORMAT_ID) |
4734 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4735 | |
edb39592 | 4736 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
4737 | values[n++] += perf_event_count(sub); |
4738 | if (read_format & PERF_FORMAT_ID) | |
4739 | values[n++] = primary_event_id(sub); | |
4740 | } | |
7d88962e | 4741 | |
2aeb1883 | 4742 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4743 | return 0; |
fa8c2693 | 4744 | } |
3dab77fb | 4745 | |
fa8c2693 PZ |
4746 | static int perf_read_group(struct perf_event *event, |
4747 | u64 read_format, char __user *buf) | |
4748 | { | |
4749 | struct perf_event *leader = event->group_leader, *child; | |
4750 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4751 | int ret; |
fa8c2693 | 4752 | u64 *values; |
3dab77fb | 4753 | |
fa8c2693 | 4754 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4755 | |
fa8c2693 PZ |
4756 | values = kzalloc(event->read_size, GFP_KERNEL); |
4757 | if (!values) | |
4758 | return -ENOMEM; | |
3dab77fb | 4759 | |
fa8c2693 PZ |
4760 | values[0] = 1 + leader->nr_siblings; |
4761 | ||
4762 | /* | |
4763 | * By locking the child_mutex of the leader we effectively | |
4764 | * lock the child list of all siblings.. XXX explain how. | |
4765 | */ | |
4766 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4767 | |
7d88962e SB |
4768 | ret = __perf_read_group_add(leader, read_format, values); |
4769 | if (ret) | |
4770 | goto unlock; | |
4771 | ||
4772 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4773 | ret = __perf_read_group_add(child, read_format, values); | |
4774 | if (ret) | |
4775 | goto unlock; | |
4776 | } | |
abf4868b | 4777 | |
fa8c2693 | 4778 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4779 | |
7d88962e | 4780 | ret = event->read_size; |
fa8c2693 PZ |
4781 | if (copy_to_user(buf, values, event->read_size)) |
4782 | ret = -EFAULT; | |
7d88962e | 4783 | goto out; |
fa8c2693 | 4784 | |
7d88962e SB |
4785 | unlock: |
4786 | mutex_unlock(&leader->child_mutex); | |
4787 | out: | |
fa8c2693 | 4788 | kfree(values); |
abf4868b | 4789 | return ret; |
3dab77fb PZ |
4790 | } |
4791 | ||
b15f495b | 4792 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4793 | u64 read_format, char __user *buf) |
4794 | { | |
59ed446f | 4795 | u64 enabled, running; |
3dab77fb PZ |
4796 | u64 values[4]; |
4797 | int n = 0; | |
4798 | ||
ca0dd44c | 4799 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4800 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4801 | values[n++] = enabled; | |
4802 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4803 | values[n++] = running; | |
3dab77fb | 4804 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4805 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4806 | |
4807 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4808 | return -EFAULT; | |
4809 | ||
4810 | return n * sizeof(u64); | |
4811 | } | |
4812 | ||
dc633982 JO |
4813 | static bool is_event_hup(struct perf_event *event) |
4814 | { | |
4815 | bool no_children; | |
4816 | ||
a69b0ca4 | 4817 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4818 | return false; |
4819 | ||
4820 | mutex_lock(&event->child_mutex); | |
4821 | no_children = list_empty(&event->child_list); | |
4822 | mutex_unlock(&event->child_mutex); | |
4823 | return no_children; | |
4824 | } | |
4825 | ||
0793a61d | 4826 | /* |
cdd6c482 | 4827 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4828 | */ |
4829 | static ssize_t | |
b15f495b | 4830 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4831 | { |
cdd6c482 | 4832 | u64 read_format = event->attr.read_format; |
3dab77fb | 4833 | int ret; |
0793a61d | 4834 | |
3b6f9e5c | 4835 | /* |
788faab7 | 4836 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
4837 | * error state (i.e. because it was pinned but it couldn't be |
4838 | * scheduled on to the CPU at some point). | |
4839 | */ | |
cdd6c482 | 4840 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4841 | return 0; |
4842 | ||
c320c7b7 | 4843 | if (count < event->read_size) |
3dab77fb PZ |
4844 | return -ENOSPC; |
4845 | ||
cdd6c482 | 4846 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4847 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4848 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4849 | else |
b15f495b | 4850 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4851 | |
3dab77fb | 4852 | return ret; |
0793a61d TG |
4853 | } |
4854 | ||
0793a61d TG |
4855 | static ssize_t |
4856 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4857 | { | |
cdd6c482 | 4858 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4859 | struct perf_event_context *ctx; |
4860 | int ret; | |
0793a61d | 4861 | |
f63a8daa | 4862 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4863 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4864 | perf_event_ctx_unlock(event, ctx); |
4865 | ||
4866 | return ret; | |
0793a61d TG |
4867 | } |
4868 | ||
9dd95748 | 4869 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 4870 | { |
cdd6c482 | 4871 | struct perf_event *event = file->private_data; |
76369139 | 4872 | struct ring_buffer *rb; |
a9a08845 | 4873 | __poll_t events = EPOLLHUP; |
c7138f37 | 4874 | |
e708d7ad | 4875 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4876 | |
dc633982 | 4877 | if (is_event_hup(event)) |
179033b3 | 4878 | return events; |
c7138f37 | 4879 | |
10c6db11 | 4880 | /* |
9bb5d40c PZ |
4881 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4882 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4883 | */ |
4884 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4885 | rb = event->rb; |
4886 | if (rb) | |
76369139 | 4887 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4888 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4889 | return events; |
4890 | } | |
4891 | ||
f63a8daa | 4892 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4893 | { |
7d88962e | 4894 | (void)perf_event_read(event, false); |
e7850595 | 4895 | local64_set(&event->count, 0); |
cdd6c482 | 4896 | perf_event_update_userpage(event); |
3df5edad PZ |
4897 | } |
4898 | ||
c93f7669 | 4899 | /* |
cdd6c482 IM |
4900 | * Holding the top-level event's child_mutex means that any |
4901 | * descendant process that has inherited this event will block | |
8ba289b8 | 4902 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4903 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4904 | */ |
cdd6c482 IM |
4905 | static void perf_event_for_each_child(struct perf_event *event, |
4906 | void (*func)(struct perf_event *)) | |
3df5edad | 4907 | { |
cdd6c482 | 4908 | struct perf_event *child; |
3df5edad | 4909 | |
cdd6c482 | 4910 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4911 | |
cdd6c482 IM |
4912 | mutex_lock(&event->child_mutex); |
4913 | func(event); | |
4914 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4915 | func(child); |
cdd6c482 | 4916 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4917 | } |
4918 | ||
cdd6c482 IM |
4919 | static void perf_event_for_each(struct perf_event *event, |
4920 | void (*func)(struct perf_event *)) | |
3df5edad | 4921 | { |
cdd6c482 IM |
4922 | struct perf_event_context *ctx = event->ctx; |
4923 | struct perf_event *sibling; | |
3df5edad | 4924 | |
f63a8daa PZ |
4925 | lockdep_assert_held(&ctx->mutex); |
4926 | ||
cdd6c482 | 4927 | event = event->group_leader; |
75f937f2 | 4928 | |
cdd6c482 | 4929 | perf_event_for_each_child(event, func); |
edb39592 | 4930 | for_each_sibling_event(sibling, event) |
724b6daa | 4931 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4932 | } |
4933 | ||
fae3fde6 PZ |
4934 | static void __perf_event_period(struct perf_event *event, |
4935 | struct perf_cpu_context *cpuctx, | |
4936 | struct perf_event_context *ctx, | |
4937 | void *info) | |
c7999c6f | 4938 | { |
fae3fde6 | 4939 | u64 value = *((u64 *)info); |
c7999c6f | 4940 | bool active; |
08247e31 | 4941 | |
cdd6c482 | 4942 | if (event->attr.freq) { |
cdd6c482 | 4943 | event->attr.sample_freq = value; |
08247e31 | 4944 | } else { |
cdd6c482 IM |
4945 | event->attr.sample_period = value; |
4946 | event->hw.sample_period = value; | |
08247e31 | 4947 | } |
bad7192b PZ |
4948 | |
4949 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4950 | if (active) { | |
4951 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4952 | /* |
4953 | * We could be throttled; unthrottle now to avoid the tick | |
4954 | * trying to unthrottle while we already re-started the event. | |
4955 | */ | |
4956 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4957 | event->hw.interrupts = 0; | |
4958 | perf_log_throttle(event, 1); | |
4959 | } | |
bad7192b PZ |
4960 | event->pmu->stop(event, PERF_EF_UPDATE); |
4961 | } | |
4962 | ||
4963 | local64_set(&event->hw.period_left, 0); | |
4964 | ||
4965 | if (active) { | |
4966 | event->pmu->start(event, PERF_EF_RELOAD); | |
4967 | perf_pmu_enable(ctx->pmu); | |
4968 | } | |
c7999c6f PZ |
4969 | } |
4970 | ||
4971 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4972 | { | |
c7999c6f PZ |
4973 | u64 value; |
4974 | ||
4975 | if (!is_sampling_event(event)) | |
4976 | return -EINVAL; | |
4977 | ||
4978 | if (copy_from_user(&value, arg, sizeof(value))) | |
4979 | return -EFAULT; | |
4980 | ||
4981 | if (!value) | |
4982 | return -EINVAL; | |
4983 | ||
4984 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4985 | return -EINVAL; | |
4986 | ||
fae3fde6 | 4987 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4988 | |
c7999c6f | 4989 | return 0; |
08247e31 PZ |
4990 | } |
4991 | ||
ac9721f3 PZ |
4992 | static const struct file_operations perf_fops; |
4993 | ||
2903ff01 | 4994 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4995 | { |
2903ff01 AV |
4996 | struct fd f = fdget(fd); |
4997 | if (!f.file) | |
4998 | return -EBADF; | |
ac9721f3 | 4999 | |
2903ff01 AV |
5000 | if (f.file->f_op != &perf_fops) { |
5001 | fdput(f); | |
5002 | return -EBADF; | |
ac9721f3 | 5003 | } |
2903ff01 AV |
5004 | *p = f; |
5005 | return 0; | |
ac9721f3 PZ |
5006 | } |
5007 | ||
5008 | static int perf_event_set_output(struct perf_event *event, | |
5009 | struct perf_event *output_event); | |
6fb2915d | 5010 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5011 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5012 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5013 | struct perf_event_attr *attr); | |
a4be7c27 | 5014 | |
f63a8daa | 5015 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5016 | { |
cdd6c482 | 5017 | void (*func)(struct perf_event *); |
3df5edad | 5018 | u32 flags = arg; |
d859e29f PM |
5019 | |
5020 | switch (cmd) { | |
cdd6c482 | 5021 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5022 | func = _perf_event_enable; |
d859e29f | 5023 | break; |
cdd6c482 | 5024 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5025 | func = _perf_event_disable; |
79f14641 | 5026 | break; |
cdd6c482 | 5027 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5028 | func = _perf_event_reset; |
6de6a7b9 | 5029 | break; |
3df5edad | 5030 | |
cdd6c482 | 5031 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5032 | return _perf_event_refresh(event, arg); |
08247e31 | 5033 | |
cdd6c482 IM |
5034 | case PERF_EVENT_IOC_PERIOD: |
5035 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 5036 | |
cf4957f1 JO |
5037 | case PERF_EVENT_IOC_ID: |
5038 | { | |
5039 | u64 id = primary_event_id(event); | |
5040 | ||
5041 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5042 | return -EFAULT; | |
5043 | return 0; | |
5044 | } | |
5045 | ||
cdd6c482 | 5046 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5047 | { |
ac9721f3 | 5048 | int ret; |
ac9721f3 | 5049 | if (arg != -1) { |
2903ff01 AV |
5050 | struct perf_event *output_event; |
5051 | struct fd output; | |
5052 | ret = perf_fget_light(arg, &output); | |
5053 | if (ret) | |
5054 | return ret; | |
5055 | output_event = output.file->private_data; | |
5056 | ret = perf_event_set_output(event, output_event); | |
5057 | fdput(output); | |
5058 | } else { | |
5059 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5060 | } |
ac9721f3 PZ |
5061 | return ret; |
5062 | } | |
a4be7c27 | 5063 | |
6fb2915d LZ |
5064 | case PERF_EVENT_IOC_SET_FILTER: |
5065 | return perf_event_set_filter(event, (void __user *)arg); | |
5066 | ||
2541517c AS |
5067 | case PERF_EVENT_IOC_SET_BPF: |
5068 | return perf_event_set_bpf_prog(event, arg); | |
5069 | ||
86e7972f WN |
5070 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
5071 | struct ring_buffer *rb; | |
5072 | ||
5073 | rcu_read_lock(); | |
5074 | rb = rcu_dereference(event->rb); | |
5075 | if (!rb || !rb->nr_pages) { | |
5076 | rcu_read_unlock(); | |
5077 | return -EINVAL; | |
5078 | } | |
5079 | rb_toggle_paused(rb, !!arg); | |
5080 | rcu_read_unlock(); | |
5081 | return 0; | |
5082 | } | |
f371b304 YS |
5083 | |
5084 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5085 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5086 | |
5087 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5088 | struct perf_event_attr new_attr; | |
5089 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5090 | &new_attr); | |
5091 | ||
5092 | if (err) | |
5093 | return err; | |
5094 | ||
5095 | return perf_event_modify_attr(event, &new_attr); | |
5096 | } | |
d859e29f | 5097 | default: |
3df5edad | 5098 | return -ENOTTY; |
d859e29f | 5099 | } |
3df5edad PZ |
5100 | |
5101 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5102 | perf_event_for_each(event, func); |
3df5edad | 5103 | else |
cdd6c482 | 5104 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5105 | |
5106 | return 0; | |
d859e29f PM |
5107 | } |
5108 | ||
f63a8daa PZ |
5109 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5110 | { | |
5111 | struct perf_event *event = file->private_data; | |
5112 | struct perf_event_context *ctx; | |
5113 | long ret; | |
5114 | ||
5115 | ctx = perf_event_ctx_lock(event); | |
5116 | ret = _perf_ioctl(event, cmd, arg); | |
5117 | perf_event_ctx_unlock(event, ctx); | |
5118 | ||
5119 | return ret; | |
5120 | } | |
5121 | ||
b3f20785 PM |
5122 | #ifdef CONFIG_COMPAT |
5123 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5124 | unsigned long arg) | |
5125 | { | |
5126 | switch (_IOC_NR(cmd)) { | |
5127 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5128 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5129 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5130 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5131 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5132 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5133 | cmd &= ~IOCSIZE_MASK; | |
5134 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5135 | } | |
5136 | break; | |
5137 | } | |
5138 | return perf_ioctl(file, cmd, arg); | |
5139 | } | |
5140 | #else | |
5141 | # define perf_compat_ioctl NULL | |
5142 | #endif | |
5143 | ||
cdd6c482 | 5144 | int perf_event_task_enable(void) |
771d7cde | 5145 | { |
f63a8daa | 5146 | struct perf_event_context *ctx; |
cdd6c482 | 5147 | struct perf_event *event; |
771d7cde | 5148 | |
cdd6c482 | 5149 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5150 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5151 | ctx = perf_event_ctx_lock(event); | |
5152 | perf_event_for_each_child(event, _perf_event_enable); | |
5153 | perf_event_ctx_unlock(event, ctx); | |
5154 | } | |
cdd6c482 | 5155 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5156 | |
5157 | return 0; | |
5158 | } | |
5159 | ||
cdd6c482 | 5160 | int perf_event_task_disable(void) |
771d7cde | 5161 | { |
f63a8daa | 5162 | struct perf_event_context *ctx; |
cdd6c482 | 5163 | struct perf_event *event; |
771d7cde | 5164 | |
cdd6c482 | 5165 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5166 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5167 | ctx = perf_event_ctx_lock(event); | |
5168 | perf_event_for_each_child(event, _perf_event_disable); | |
5169 | perf_event_ctx_unlock(event, ctx); | |
5170 | } | |
cdd6c482 | 5171 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5172 | |
5173 | return 0; | |
5174 | } | |
5175 | ||
cdd6c482 | 5176 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5177 | { |
a4eaf7f1 PZ |
5178 | if (event->hw.state & PERF_HES_STOPPED) |
5179 | return 0; | |
5180 | ||
cdd6c482 | 5181 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5182 | return 0; |
5183 | ||
35edc2a5 | 5184 | return event->pmu->event_idx(event); |
194002b2 PZ |
5185 | } |
5186 | ||
c4794295 | 5187 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5188 | u64 *now, |
7f310a5d EM |
5189 | u64 *enabled, |
5190 | u64 *running) | |
c4794295 | 5191 | { |
e3f3541c | 5192 | u64 ctx_time; |
c4794295 | 5193 | |
e3f3541c PZ |
5194 | *now = perf_clock(); |
5195 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5196 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5197 | } |
5198 | ||
fa731587 PZ |
5199 | static void perf_event_init_userpage(struct perf_event *event) |
5200 | { | |
5201 | struct perf_event_mmap_page *userpg; | |
5202 | struct ring_buffer *rb; | |
5203 | ||
5204 | rcu_read_lock(); | |
5205 | rb = rcu_dereference(event->rb); | |
5206 | if (!rb) | |
5207 | goto unlock; | |
5208 | ||
5209 | userpg = rb->user_page; | |
5210 | ||
5211 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5212 | userpg->cap_bit0_is_deprecated = 1; | |
5213 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5214 | userpg->data_offset = PAGE_SIZE; |
5215 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5216 | |
5217 | unlock: | |
5218 | rcu_read_unlock(); | |
5219 | } | |
5220 | ||
c1317ec2 AL |
5221 | void __weak arch_perf_update_userpage( |
5222 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5223 | { |
5224 | } | |
5225 | ||
38ff667b PZ |
5226 | /* |
5227 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5228 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5229 | * code calls this from NMI context. | |
5230 | */ | |
cdd6c482 | 5231 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5232 | { |
cdd6c482 | 5233 | struct perf_event_mmap_page *userpg; |
76369139 | 5234 | struct ring_buffer *rb; |
e3f3541c | 5235 | u64 enabled, running, now; |
38ff667b PZ |
5236 | |
5237 | rcu_read_lock(); | |
5ec4c599 PZ |
5238 | rb = rcu_dereference(event->rb); |
5239 | if (!rb) | |
5240 | goto unlock; | |
5241 | ||
0d641208 EM |
5242 | /* |
5243 | * compute total_time_enabled, total_time_running | |
5244 | * based on snapshot values taken when the event | |
5245 | * was last scheduled in. | |
5246 | * | |
5247 | * we cannot simply called update_context_time() | |
5248 | * because of locking issue as we can be called in | |
5249 | * NMI context | |
5250 | */ | |
e3f3541c | 5251 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5252 | |
76369139 | 5253 | userpg = rb->user_page; |
7b732a75 | 5254 | /* |
9d2dcc8f MF |
5255 | * Disable preemption to guarantee consistent time stamps are stored to |
5256 | * the user page. | |
7b732a75 PZ |
5257 | */ |
5258 | preempt_disable(); | |
37d81828 | 5259 | ++userpg->lock; |
92f22a38 | 5260 | barrier(); |
cdd6c482 | 5261 | userpg->index = perf_event_index(event); |
b5e58793 | 5262 | userpg->offset = perf_event_count(event); |
365a4038 | 5263 | if (userpg->index) |
e7850595 | 5264 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5265 | |
0d641208 | 5266 | userpg->time_enabled = enabled + |
cdd6c482 | 5267 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5268 | |
0d641208 | 5269 | userpg->time_running = running + |
cdd6c482 | 5270 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5271 | |
c1317ec2 | 5272 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5273 | |
92f22a38 | 5274 | barrier(); |
37d81828 | 5275 | ++userpg->lock; |
7b732a75 | 5276 | preempt_enable(); |
38ff667b | 5277 | unlock: |
7b732a75 | 5278 | rcu_read_unlock(); |
37d81828 | 5279 | } |
82975c46 | 5280 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5281 | |
9e3ed2d7 | 5282 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5283 | { |
11bac800 | 5284 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 5285 | struct ring_buffer *rb; |
9e3ed2d7 | 5286 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5287 | |
5288 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5289 | if (vmf->pgoff == 0) | |
5290 | ret = 0; | |
5291 | return ret; | |
5292 | } | |
5293 | ||
5294 | rcu_read_lock(); | |
76369139 FW |
5295 | rb = rcu_dereference(event->rb); |
5296 | if (!rb) | |
906010b2 PZ |
5297 | goto unlock; |
5298 | ||
5299 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5300 | goto unlock; | |
5301 | ||
76369139 | 5302 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5303 | if (!vmf->page) |
5304 | goto unlock; | |
5305 | ||
5306 | get_page(vmf->page); | |
11bac800 | 5307 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5308 | vmf->page->index = vmf->pgoff; |
5309 | ||
5310 | ret = 0; | |
5311 | unlock: | |
5312 | rcu_read_unlock(); | |
5313 | ||
5314 | return ret; | |
5315 | } | |
5316 | ||
10c6db11 PZ |
5317 | static void ring_buffer_attach(struct perf_event *event, |
5318 | struct ring_buffer *rb) | |
5319 | { | |
b69cf536 | 5320 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5321 | unsigned long flags; |
5322 | ||
b69cf536 PZ |
5323 | if (event->rb) { |
5324 | /* | |
5325 | * Should be impossible, we set this when removing | |
5326 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5327 | */ | |
5328 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5329 | |
b69cf536 | 5330 | old_rb = event->rb; |
b69cf536 PZ |
5331 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5332 | list_del_rcu(&event->rb_entry); | |
5333 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5334 | |
2f993cf0 ON |
5335 | event->rcu_batches = get_state_synchronize_rcu(); |
5336 | event->rcu_pending = 1; | |
b69cf536 | 5337 | } |
10c6db11 | 5338 | |
b69cf536 | 5339 | if (rb) { |
2f993cf0 ON |
5340 | if (event->rcu_pending) { |
5341 | cond_synchronize_rcu(event->rcu_batches); | |
5342 | event->rcu_pending = 0; | |
5343 | } | |
5344 | ||
b69cf536 PZ |
5345 | spin_lock_irqsave(&rb->event_lock, flags); |
5346 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5347 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5348 | } | |
5349 | ||
767ae086 AS |
5350 | /* |
5351 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5352 | * before swizzling the event::rb pointer; if it's getting | |
5353 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5354 | * restart. See the comment in __perf_pmu_output_stop(). | |
5355 | * | |
5356 | * Data will inevitably be lost when set_output is done in | |
5357 | * mid-air, but then again, whoever does it like this is | |
5358 | * not in for the data anyway. | |
5359 | */ | |
5360 | if (has_aux(event)) | |
5361 | perf_event_stop(event, 0); | |
5362 | ||
b69cf536 PZ |
5363 | rcu_assign_pointer(event->rb, rb); |
5364 | ||
5365 | if (old_rb) { | |
5366 | ring_buffer_put(old_rb); | |
5367 | /* | |
5368 | * Since we detached before setting the new rb, so that we | |
5369 | * could attach the new rb, we could have missed a wakeup. | |
5370 | * Provide it now. | |
5371 | */ | |
5372 | wake_up_all(&event->waitq); | |
5373 | } | |
10c6db11 PZ |
5374 | } |
5375 | ||
5376 | static void ring_buffer_wakeup(struct perf_event *event) | |
5377 | { | |
5378 | struct ring_buffer *rb; | |
5379 | ||
5380 | rcu_read_lock(); | |
5381 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5382 | if (rb) { |
5383 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5384 | wake_up_all(&event->waitq); | |
5385 | } | |
10c6db11 PZ |
5386 | rcu_read_unlock(); |
5387 | } | |
5388 | ||
fdc26706 | 5389 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5390 | { |
76369139 | 5391 | struct ring_buffer *rb; |
7b732a75 | 5392 | |
ac9721f3 | 5393 | rcu_read_lock(); |
76369139 FW |
5394 | rb = rcu_dereference(event->rb); |
5395 | if (rb) { | |
5396 | if (!atomic_inc_not_zero(&rb->refcount)) | |
5397 | rb = NULL; | |
ac9721f3 PZ |
5398 | } |
5399 | rcu_read_unlock(); | |
5400 | ||
76369139 | 5401 | return rb; |
ac9721f3 PZ |
5402 | } |
5403 | ||
fdc26706 | 5404 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5405 | { |
76369139 | 5406 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 5407 | return; |
7b732a75 | 5408 | |
9bb5d40c | 5409 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5410 | |
76369139 | 5411 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5412 | } |
5413 | ||
5414 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5415 | { | |
cdd6c482 | 5416 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5417 | |
cdd6c482 | 5418 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5419 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5420 | |
45bfb2e5 PZ |
5421 | if (vma->vm_pgoff) |
5422 | atomic_inc(&event->rb->aux_mmap_count); | |
5423 | ||
1e0fb9ec | 5424 | if (event->pmu->event_mapped) |
bfe33492 | 5425 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5426 | } |
5427 | ||
95ff4ca2 AS |
5428 | static void perf_pmu_output_stop(struct perf_event *event); |
5429 | ||
9bb5d40c PZ |
5430 | /* |
5431 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5432 | * event, or through other events by use of perf_event_set_output(). | |
5433 | * | |
5434 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5435 | * the buffer here, where we still have a VM context. This means we need | |
5436 | * to detach all events redirecting to us. | |
5437 | */ | |
7b732a75 PZ |
5438 | static void perf_mmap_close(struct vm_area_struct *vma) |
5439 | { | |
cdd6c482 | 5440 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5441 | |
b69cf536 | 5442 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5443 | struct user_struct *mmap_user = rb->mmap_user; |
5444 | int mmap_locked = rb->mmap_locked; | |
5445 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5446 | |
1e0fb9ec | 5447 | if (event->pmu->event_unmapped) |
bfe33492 | 5448 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5449 | |
45bfb2e5 PZ |
5450 | /* |
5451 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5452 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5453 | * serialize with perf_mmap here. | |
5454 | */ | |
5455 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5456 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5457 | /* |
5458 | * Stop all AUX events that are writing to this buffer, | |
5459 | * so that we can free its AUX pages and corresponding PMU | |
5460 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5461 | * they won't start any more (see perf_aux_output_begin()). | |
5462 | */ | |
5463 | perf_pmu_output_stop(event); | |
5464 | ||
5465 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5466 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5467 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5468 | ||
95ff4ca2 | 5469 | /* this has to be the last one */ |
45bfb2e5 | 5470 | rb_free_aux(rb); |
95ff4ca2 AS |
5471 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5472 | ||
45bfb2e5 PZ |
5473 | mutex_unlock(&event->mmap_mutex); |
5474 | } | |
5475 | ||
9bb5d40c PZ |
5476 | atomic_dec(&rb->mmap_count); |
5477 | ||
5478 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5479 | goto out_put; |
9bb5d40c | 5480 | |
b69cf536 | 5481 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5482 | mutex_unlock(&event->mmap_mutex); |
5483 | ||
5484 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5485 | if (atomic_read(&rb->mmap_count)) |
5486 | goto out_put; | |
ac9721f3 | 5487 | |
9bb5d40c PZ |
5488 | /* |
5489 | * No other mmap()s, detach from all other events that might redirect | |
5490 | * into the now unreachable buffer. Somewhat complicated by the | |
5491 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5492 | */ | |
5493 | again: | |
5494 | rcu_read_lock(); | |
5495 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5496 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5497 | /* | |
5498 | * This event is en-route to free_event() which will | |
5499 | * detach it and remove it from the list. | |
5500 | */ | |
5501 | continue; | |
5502 | } | |
5503 | rcu_read_unlock(); | |
789f90fc | 5504 | |
9bb5d40c PZ |
5505 | mutex_lock(&event->mmap_mutex); |
5506 | /* | |
5507 | * Check we didn't race with perf_event_set_output() which can | |
5508 | * swizzle the rb from under us while we were waiting to | |
5509 | * acquire mmap_mutex. | |
5510 | * | |
5511 | * If we find a different rb; ignore this event, a next | |
5512 | * iteration will no longer find it on the list. We have to | |
5513 | * still restart the iteration to make sure we're not now | |
5514 | * iterating the wrong list. | |
5515 | */ | |
b69cf536 PZ |
5516 | if (event->rb == rb) |
5517 | ring_buffer_attach(event, NULL); | |
5518 | ||
cdd6c482 | 5519 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5520 | put_event(event); |
ac9721f3 | 5521 | |
9bb5d40c PZ |
5522 | /* |
5523 | * Restart the iteration; either we're on the wrong list or | |
5524 | * destroyed its integrity by doing a deletion. | |
5525 | */ | |
5526 | goto again; | |
7b732a75 | 5527 | } |
9bb5d40c PZ |
5528 | rcu_read_unlock(); |
5529 | ||
5530 | /* | |
5531 | * It could be there's still a few 0-ref events on the list; they'll | |
5532 | * get cleaned up by free_event() -- they'll also still have their | |
5533 | * ref on the rb and will free it whenever they are done with it. | |
5534 | * | |
5535 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5536 | * undo the VM accounting. | |
5537 | */ | |
5538 | ||
5539 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5540 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5541 | free_uid(mmap_user); | |
5542 | ||
b69cf536 | 5543 | out_put: |
9bb5d40c | 5544 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5545 | } |
5546 | ||
f0f37e2f | 5547 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5548 | .open = perf_mmap_open, |
fca0c116 | 5549 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5550 | .fault = perf_mmap_fault, |
5551 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5552 | }; |
5553 | ||
5554 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5555 | { | |
cdd6c482 | 5556 | struct perf_event *event = file->private_data; |
22a4f650 | 5557 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5558 | struct user_struct *user = current_user(); |
22a4f650 | 5559 | unsigned long locked, lock_limit; |
45bfb2e5 | 5560 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5561 | unsigned long vma_size; |
5562 | unsigned long nr_pages; | |
45bfb2e5 | 5563 | long user_extra = 0, extra = 0; |
d57e34fd | 5564 | int ret = 0, flags = 0; |
37d81828 | 5565 | |
c7920614 PZ |
5566 | /* |
5567 | * Don't allow mmap() of inherited per-task counters. This would | |
5568 | * create a performance issue due to all children writing to the | |
76369139 | 5569 | * same rb. |
c7920614 PZ |
5570 | */ |
5571 | if (event->cpu == -1 && event->attr.inherit) | |
5572 | return -EINVAL; | |
5573 | ||
43a21ea8 | 5574 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5575 | return -EINVAL; |
7b732a75 PZ |
5576 | |
5577 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5578 | |
5579 | if (vma->vm_pgoff == 0) { | |
5580 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5581 | } else { | |
5582 | /* | |
5583 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5584 | * mapped, all subsequent mappings should have the same size | |
5585 | * and offset. Must be above the normal perf buffer. | |
5586 | */ | |
5587 | u64 aux_offset, aux_size; | |
5588 | ||
5589 | if (!event->rb) | |
5590 | return -EINVAL; | |
5591 | ||
5592 | nr_pages = vma_size / PAGE_SIZE; | |
5593 | ||
5594 | mutex_lock(&event->mmap_mutex); | |
5595 | ret = -EINVAL; | |
5596 | ||
5597 | rb = event->rb; | |
5598 | if (!rb) | |
5599 | goto aux_unlock; | |
5600 | ||
6aa7de05 MR |
5601 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5602 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5603 | |
5604 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5605 | goto aux_unlock; | |
5606 | ||
5607 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5608 | goto aux_unlock; | |
5609 | ||
5610 | /* already mapped with a different offset */ | |
5611 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5612 | goto aux_unlock; | |
5613 | ||
5614 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5615 | goto aux_unlock; | |
5616 | ||
5617 | /* already mapped with a different size */ | |
5618 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5619 | goto aux_unlock; | |
5620 | ||
5621 | if (!is_power_of_2(nr_pages)) | |
5622 | goto aux_unlock; | |
5623 | ||
5624 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5625 | goto aux_unlock; | |
5626 | ||
5627 | if (rb_has_aux(rb)) { | |
5628 | atomic_inc(&rb->aux_mmap_count); | |
5629 | ret = 0; | |
5630 | goto unlock; | |
5631 | } | |
5632 | ||
5633 | atomic_set(&rb->aux_mmap_count, 1); | |
5634 | user_extra = nr_pages; | |
5635 | ||
5636 | goto accounting; | |
5637 | } | |
7b732a75 | 5638 | |
7730d865 | 5639 | /* |
76369139 | 5640 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5641 | * can do bitmasks instead of modulo. |
5642 | */ | |
2ed11312 | 5643 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5644 | return -EINVAL; |
5645 | ||
7b732a75 | 5646 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5647 | return -EINVAL; |
5648 | ||
cdd6c482 | 5649 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5650 | again: |
cdd6c482 | 5651 | mutex_lock(&event->mmap_mutex); |
76369139 | 5652 | if (event->rb) { |
9bb5d40c | 5653 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5654 | ret = -EINVAL; |
9bb5d40c PZ |
5655 | goto unlock; |
5656 | } | |
5657 | ||
5658 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5659 | /* | |
5660 | * Raced against perf_mmap_close() through | |
5661 | * perf_event_set_output(). Try again, hope for better | |
5662 | * luck. | |
5663 | */ | |
5664 | mutex_unlock(&event->mmap_mutex); | |
5665 | goto again; | |
5666 | } | |
5667 | ||
ebb3c4c4 PZ |
5668 | goto unlock; |
5669 | } | |
5670 | ||
789f90fc | 5671 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5672 | |
5673 | accounting: | |
cdd6c482 | 5674 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5675 | |
5676 | /* | |
5677 | * Increase the limit linearly with more CPUs: | |
5678 | */ | |
5679 | user_lock_limit *= num_online_cpus(); | |
5680 | ||
789f90fc | 5681 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5682 | |
789f90fc PZ |
5683 | if (user_locked > user_lock_limit) |
5684 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5685 | |
78d7d407 | 5686 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5687 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5688 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5689 | |
459ec28a IM |
5690 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5691 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5692 | ret = -EPERM; |
5693 | goto unlock; | |
5694 | } | |
7b732a75 | 5695 | |
45bfb2e5 | 5696 | WARN_ON(!rb && event->rb); |
906010b2 | 5697 | |
d57e34fd | 5698 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5699 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5700 | |
76369139 | 5701 | if (!rb) { |
45bfb2e5 PZ |
5702 | rb = rb_alloc(nr_pages, |
5703 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5704 | event->cpu, flags); | |
26cb63ad | 5705 | |
45bfb2e5 PZ |
5706 | if (!rb) { |
5707 | ret = -ENOMEM; | |
5708 | goto unlock; | |
5709 | } | |
43a21ea8 | 5710 | |
45bfb2e5 PZ |
5711 | atomic_set(&rb->mmap_count, 1); |
5712 | rb->mmap_user = get_current_user(); | |
5713 | rb->mmap_locked = extra; | |
26cb63ad | 5714 | |
45bfb2e5 | 5715 | ring_buffer_attach(event, rb); |
ac9721f3 | 5716 | |
45bfb2e5 PZ |
5717 | perf_event_init_userpage(event); |
5718 | perf_event_update_userpage(event); | |
5719 | } else { | |
1a594131 AS |
5720 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5721 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5722 | if (!ret) |
5723 | rb->aux_mmap_locked = extra; | |
5724 | } | |
9a0f05cb | 5725 | |
ebb3c4c4 | 5726 | unlock: |
45bfb2e5 PZ |
5727 | if (!ret) { |
5728 | atomic_long_add(user_extra, &user->locked_vm); | |
5729 | vma->vm_mm->pinned_vm += extra; | |
5730 | ||
ac9721f3 | 5731 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5732 | } else if (rb) { |
5733 | atomic_dec(&rb->mmap_count); | |
5734 | } | |
5735 | aux_unlock: | |
cdd6c482 | 5736 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5737 | |
9bb5d40c PZ |
5738 | /* |
5739 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5740 | * vma. | |
5741 | */ | |
26cb63ad | 5742 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5743 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5744 | |
1e0fb9ec | 5745 | if (event->pmu->event_mapped) |
bfe33492 | 5746 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5747 | |
7b732a75 | 5748 | return ret; |
37d81828 PM |
5749 | } |
5750 | ||
3c446b3d PZ |
5751 | static int perf_fasync(int fd, struct file *filp, int on) |
5752 | { | |
496ad9aa | 5753 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5754 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5755 | int retval; |
5756 | ||
5955102c | 5757 | inode_lock(inode); |
cdd6c482 | 5758 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5759 | inode_unlock(inode); |
3c446b3d PZ |
5760 | |
5761 | if (retval < 0) | |
5762 | return retval; | |
5763 | ||
5764 | return 0; | |
5765 | } | |
5766 | ||
0793a61d | 5767 | static const struct file_operations perf_fops = { |
3326c1ce | 5768 | .llseek = no_llseek, |
0793a61d TG |
5769 | .release = perf_release, |
5770 | .read = perf_read, | |
5771 | .poll = perf_poll, | |
d859e29f | 5772 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5773 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5774 | .mmap = perf_mmap, |
3c446b3d | 5775 | .fasync = perf_fasync, |
0793a61d TG |
5776 | }; |
5777 | ||
925d519a | 5778 | /* |
cdd6c482 | 5779 | * Perf event wakeup |
925d519a PZ |
5780 | * |
5781 | * If there's data, ensure we set the poll() state and publish everything | |
5782 | * to user-space before waking everybody up. | |
5783 | */ | |
5784 | ||
fed66e2c PZ |
5785 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5786 | { | |
5787 | /* only the parent has fasync state */ | |
5788 | if (event->parent) | |
5789 | event = event->parent; | |
5790 | return &event->fasync; | |
5791 | } | |
5792 | ||
cdd6c482 | 5793 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5794 | { |
10c6db11 | 5795 | ring_buffer_wakeup(event); |
4c9e2542 | 5796 | |
cdd6c482 | 5797 | if (event->pending_kill) { |
fed66e2c | 5798 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5799 | event->pending_kill = 0; |
4c9e2542 | 5800 | } |
925d519a PZ |
5801 | } |
5802 | ||
e360adbe | 5803 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5804 | { |
cdd6c482 IM |
5805 | struct perf_event *event = container_of(entry, |
5806 | struct perf_event, pending); | |
d525211f PZ |
5807 | int rctx; |
5808 | ||
5809 | rctx = perf_swevent_get_recursion_context(); | |
5810 | /* | |
5811 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5812 | * and we won't recurse 'further'. | |
5813 | */ | |
79f14641 | 5814 | |
cdd6c482 IM |
5815 | if (event->pending_disable) { |
5816 | event->pending_disable = 0; | |
fae3fde6 | 5817 | perf_event_disable_local(event); |
79f14641 PZ |
5818 | } |
5819 | ||
cdd6c482 IM |
5820 | if (event->pending_wakeup) { |
5821 | event->pending_wakeup = 0; | |
5822 | perf_event_wakeup(event); | |
79f14641 | 5823 | } |
d525211f PZ |
5824 | |
5825 | if (rctx >= 0) | |
5826 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5827 | } |
5828 | ||
39447b38 ZY |
5829 | /* |
5830 | * We assume there is only KVM supporting the callbacks. | |
5831 | * Later on, we might change it to a list if there is | |
5832 | * another virtualization implementation supporting the callbacks. | |
5833 | */ | |
5834 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5835 | ||
5836 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5837 | { | |
5838 | perf_guest_cbs = cbs; | |
5839 | return 0; | |
5840 | } | |
5841 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5842 | ||
5843 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5844 | { | |
5845 | perf_guest_cbs = NULL; | |
5846 | return 0; | |
5847 | } | |
5848 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5849 | ||
4018994f JO |
5850 | static void |
5851 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5852 | struct pt_regs *regs, u64 mask) | |
5853 | { | |
5854 | int bit; | |
29dd3288 | 5855 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5856 | |
29dd3288 MS |
5857 | bitmap_from_u64(_mask, mask); |
5858 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5859 | u64 val; |
5860 | ||
5861 | val = perf_reg_value(regs, bit); | |
5862 | perf_output_put(handle, val); | |
5863 | } | |
5864 | } | |
5865 | ||
60e2364e | 5866 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5867 | struct pt_regs *regs, |
5868 | struct pt_regs *regs_user_copy) | |
4018994f | 5869 | { |
88a7c26a AL |
5870 | if (user_mode(regs)) { |
5871 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5872 | regs_user->regs = regs; |
88a7c26a AL |
5873 | } else if (current->mm) { |
5874 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5875 | } else { |
5876 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5877 | regs_user->regs = NULL; | |
4018994f JO |
5878 | } |
5879 | } | |
5880 | ||
60e2364e SE |
5881 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5882 | struct pt_regs *regs) | |
5883 | { | |
5884 | regs_intr->regs = regs; | |
5885 | regs_intr->abi = perf_reg_abi(current); | |
5886 | } | |
5887 | ||
5888 | ||
c5ebcedb JO |
5889 | /* |
5890 | * Get remaining task size from user stack pointer. | |
5891 | * | |
5892 | * It'd be better to take stack vma map and limit this more | |
5893 | * precisly, but there's no way to get it safely under interrupt, | |
5894 | * so using TASK_SIZE as limit. | |
5895 | */ | |
5896 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5897 | { | |
5898 | unsigned long addr = perf_user_stack_pointer(regs); | |
5899 | ||
5900 | if (!addr || addr >= TASK_SIZE) | |
5901 | return 0; | |
5902 | ||
5903 | return TASK_SIZE - addr; | |
5904 | } | |
5905 | ||
5906 | static u16 | |
5907 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5908 | struct pt_regs *regs) | |
5909 | { | |
5910 | u64 task_size; | |
5911 | ||
5912 | /* No regs, no stack pointer, no dump. */ | |
5913 | if (!regs) | |
5914 | return 0; | |
5915 | ||
5916 | /* | |
5917 | * Check if we fit in with the requested stack size into the: | |
5918 | * - TASK_SIZE | |
5919 | * If we don't, we limit the size to the TASK_SIZE. | |
5920 | * | |
5921 | * - remaining sample size | |
5922 | * If we don't, we customize the stack size to | |
5923 | * fit in to the remaining sample size. | |
5924 | */ | |
5925 | ||
5926 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5927 | stack_size = min(stack_size, (u16) task_size); | |
5928 | ||
5929 | /* Current header size plus static size and dynamic size. */ | |
5930 | header_size += 2 * sizeof(u64); | |
5931 | ||
5932 | /* Do we fit in with the current stack dump size? */ | |
5933 | if ((u16) (header_size + stack_size) < header_size) { | |
5934 | /* | |
5935 | * If we overflow the maximum size for the sample, | |
5936 | * we customize the stack dump size to fit in. | |
5937 | */ | |
5938 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5939 | stack_size = round_up(stack_size, sizeof(u64)); | |
5940 | } | |
5941 | ||
5942 | return stack_size; | |
5943 | } | |
5944 | ||
5945 | static void | |
5946 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5947 | struct pt_regs *regs) | |
5948 | { | |
5949 | /* Case of a kernel thread, nothing to dump */ | |
5950 | if (!regs) { | |
5951 | u64 size = 0; | |
5952 | perf_output_put(handle, size); | |
5953 | } else { | |
5954 | unsigned long sp; | |
5955 | unsigned int rem; | |
5956 | u64 dyn_size; | |
02e18447 | 5957 | mm_segment_t fs; |
c5ebcedb JO |
5958 | |
5959 | /* | |
5960 | * We dump: | |
5961 | * static size | |
5962 | * - the size requested by user or the best one we can fit | |
5963 | * in to the sample max size | |
5964 | * data | |
5965 | * - user stack dump data | |
5966 | * dynamic size | |
5967 | * - the actual dumped size | |
5968 | */ | |
5969 | ||
5970 | /* Static size. */ | |
5971 | perf_output_put(handle, dump_size); | |
5972 | ||
5973 | /* Data. */ | |
5974 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
5975 | fs = get_fs(); |
5976 | set_fs(USER_DS); | |
c5ebcedb | 5977 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 5978 | set_fs(fs); |
c5ebcedb JO |
5979 | dyn_size = dump_size - rem; |
5980 | ||
5981 | perf_output_skip(handle, rem); | |
5982 | ||
5983 | /* Dynamic size. */ | |
5984 | perf_output_put(handle, dyn_size); | |
5985 | } | |
5986 | } | |
5987 | ||
c980d109 ACM |
5988 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5989 | struct perf_sample_data *data, | |
5990 | struct perf_event *event) | |
6844c09d ACM |
5991 | { |
5992 | u64 sample_type = event->attr.sample_type; | |
5993 | ||
5994 | data->type = sample_type; | |
5995 | header->size += event->id_header_size; | |
5996 | ||
5997 | if (sample_type & PERF_SAMPLE_TID) { | |
5998 | /* namespace issues */ | |
5999 | data->tid_entry.pid = perf_event_pid(event, current); | |
6000 | data->tid_entry.tid = perf_event_tid(event, current); | |
6001 | } | |
6002 | ||
6003 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6004 | data->time = perf_event_clock(event); |
6844c09d | 6005 | |
ff3d527c | 6006 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6007 | data->id = primary_event_id(event); |
6008 | ||
6009 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6010 | data->stream_id = event->id; | |
6011 | ||
6012 | if (sample_type & PERF_SAMPLE_CPU) { | |
6013 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6014 | data->cpu_entry.reserved = 0; | |
6015 | } | |
6016 | } | |
6017 | ||
76369139 FW |
6018 | void perf_event_header__init_id(struct perf_event_header *header, |
6019 | struct perf_sample_data *data, | |
6020 | struct perf_event *event) | |
c980d109 ACM |
6021 | { |
6022 | if (event->attr.sample_id_all) | |
6023 | __perf_event_header__init_id(header, data, event); | |
6024 | } | |
6025 | ||
6026 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6027 | struct perf_sample_data *data) | |
6028 | { | |
6029 | u64 sample_type = data->type; | |
6030 | ||
6031 | if (sample_type & PERF_SAMPLE_TID) | |
6032 | perf_output_put(handle, data->tid_entry); | |
6033 | ||
6034 | if (sample_type & PERF_SAMPLE_TIME) | |
6035 | perf_output_put(handle, data->time); | |
6036 | ||
6037 | if (sample_type & PERF_SAMPLE_ID) | |
6038 | perf_output_put(handle, data->id); | |
6039 | ||
6040 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6041 | perf_output_put(handle, data->stream_id); | |
6042 | ||
6043 | if (sample_type & PERF_SAMPLE_CPU) | |
6044 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6045 | |
6046 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6047 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6048 | } |
6049 | ||
76369139 FW |
6050 | void perf_event__output_id_sample(struct perf_event *event, |
6051 | struct perf_output_handle *handle, | |
6052 | struct perf_sample_data *sample) | |
c980d109 ACM |
6053 | { |
6054 | if (event->attr.sample_id_all) | |
6055 | __perf_event__output_id_sample(handle, sample); | |
6056 | } | |
6057 | ||
3dab77fb | 6058 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6059 | struct perf_event *event, |
6060 | u64 enabled, u64 running) | |
3dab77fb | 6061 | { |
cdd6c482 | 6062 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6063 | u64 values[4]; |
6064 | int n = 0; | |
6065 | ||
b5e58793 | 6066 | values[n++] = perf_event_count(event); |
3dab77fb | 6067 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6068 | values[n++] = enabled + |
cdd6c482 | 6069 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6070 | } |
6071 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6072 | values[n++] = running + |
cdd6c482 | 6073 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6074 | } |
6075 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6076 | values[n++] = primary_event_id(event); |
3dab77fb | 6077 | |
76369139 | 6078 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6079 | } |
6080 | ||
3dab77fb | 6081 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6082 | struct perf_event *event, |
6083 | u64 enabled, u64 running) | |
3dab77fb | 6084 | { |
cdd6c482 IM |
6085 | struct perf_event *leader = event->group_leader, *sub; |
6086 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6087 | u64 values[5]; |
6088 | int n = 0; | |
6089 | ||
6090 | values[n++] = 1 + leader->nr_siblings; | |
6091 | ||
6092 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6093 | values[n++] = enabled; |
3dab77fb PZ |
6094 | |
6095 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6096 | values[n++] = running; |
3dab77fb | 6097 | |
9e5b127d PZ |
6098 | if ((leader != event) && |
6099 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6100 | leader->pmu->read(leader); |
6101 | ||
b5e58793 | 6102 | values[n++] = perf_event_count(leader); |
3dab77fb | 6103 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6104 | values[n++] = primary_event_id(leader); |
3dab77fb | 6105 | |
76369139 | 6106 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6107 | |
edb39592 | 6108 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6109 | n = 0; |
6110 | ||
6f5ab001 JO |
6111 | if ((sub != event) && |
6112 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6113 | sub->pmu->read(sub); |
6114 | ||
b5e58793 | 6115 | values[n++] = perf_event_count(sub); |
3dab77fb | 6116 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6117 | values[n++] = primary_event_id(sub); |
3dab77fb | 6118 | |
76369139 | 6119 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6120 | } |
6121 | } | |
6122 | ||
eed01528 SE |
6123 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6124 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6125 | ||
ba5213ae PZ |
6126 | /* |
6127 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6128 | * | |
6129 | * The problem is that its both hard and excessively expensive to iterate the | |
6130 | * child list, not to mention that its impossible to IPI the children running | |
6131 | * on another CPU, from interrupt/NMI context. | |
6132 | */ | |
3dab77fb | 6133 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6134 | struct perf_event *event) |
3dab77fb | 6135 | { |
e3f3541c | 6136 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6137 | u64 read_format = event->attr.read_format; |
6138 | ||
6139 | /* | |
6140 | * compute total_time_enabled, total_time_running | |
6141 | * based on snapshot values taken when the event | |
6142 | * was last scheduled in. | |
6143 | * | |
6144 | * we cannot simply called update_context_time() | |
6145 | * because of locking issue as we are called in | |
6146 | * NMI context | |
6147 | */ | |
c4794295 | 6148 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6149 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6150 | |
cdd6c482 | 6151 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6152 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6153 | else |
eed01528 | 6154 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6155 | } |
6156 | ||
5622f295 MM |
6157 | void perf_output_sample(struct perf_output_handle *handle, |
6158 | struct perf_event_header *header, | |
6159 | struct perf_sample_data *data, | |
cdd6c482 | 6160 | struct perf_event *event) |
5622f295 MM |
6161 | { |
6162 | u64 sample_type = data->type; | |
6163 | ||
6164 | perf_output_put(handle, *header); | |
6165 | ||
ff3d527c AH |
6166 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6167 | perf_output_put(handle, data->id); | |
6168 | ||
5622f295 MM |
6169 | if (sample_type & PERF_SAMPLE_IP) |
6170 | perf_output_put(handle, data->ip); | |
6171 | ||
6172 | if (sample_type & PERF_SAMPLE_TID) | |
6173 | perf_output_put(handle, data->tid_entry); | |
6174 | ||
6175 | if (sample_type & PERF_SAMPLE_TIME) | |
6176 | perf_output_put(handle, data->time); | |
6177 | ||
6178 | if (sample_type & PERF_SAMPLE_ADDR) | |
6179 | perf_output_put(handle, data->addr); | |
6180 | ||
6181 | if (sample_type & PERF_SAMPLE_ID) | |
6182 | perf_output_put(handle, data->id); | |
6183 | ||
6184 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6185 | perf_output_put(handle, data->stream_id); | |
6186 | ||
6187 | if (sample_type & PERF_SAMPLE_CPU) | |
6188 | perf_output_put(handle, data->cpu_entry); | |
6189 | ||
6190 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6191 | perf_output_put(handle, data->period); | |
6192 | ||
6193 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6194 | perf_output_read(handle, event); |
5622f295 MM |
6195 | |
6196 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6197 | int size = 1; |
5622f295 | 6198 | |
99e818cc JO |
6199 | size += data->callchain->nr; |
6200 | size *= sizeof(u64); | |
6201 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6202 | } |
6203 | ||
6204 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6205 | struct perf_raw_record *raw = data->raw; |
6206 | ||
6207 | if (raw) { | |
6208 | struct perf_raw_frag *frag = &raw->frag; | |
6209 | ||
6210 | perf_output_put(handle, raw->size); | |
6211 | do { | |
6212 | if (frag->copy) { | |
6213 | __output_custom(handle, frag->copy, | |
6214 | frag->data, frag->size); | |
6215 | } else { | |
6216 | __output_copy(handle, frag->data, | |
6217 | frag->size); | |
6218 | } | |
6219 | if (perf_raw_frag_last(frag)) | |
6220 | break; | |
6221 | frag = frag->next; | |
6222 | } while (1); | |
6223 | if (frag->pad) | |
6224 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6225 | } else { |
6226 | struct { | |
6227 | u32 size; | |
6228 | u32 data; | |
6229 | } raw = { | |
6230 | .size = sizeof(u32), | |
6231 | .data = 0, | |
6232 | }; | |
6233 | perf_output_put(handle, raw); | |
6234 | } | |
6235 | } | |
a7ac67ea | 6236 | |
bce38cd5 SE |
6237 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6238 | if (data->br_stack) { | |
6239 | size_t size; | |
6240 | ||
6241 | size = data->br_stack->nr | |
6242 | * sizeof(struct perf_branch_entry); | |
6243 | ||
6244 | perf_output_put(handle, data->br_stack->nr); | |
6245 | perf_output_copy(handle, data->br_stack->entries, size); | |
6246 | } else { | |
6247 | /* | |
6248 | * we always store at least the value of nr | |
6249 | */ | |
6250 | u64 nr = 0; | |
6251 | perf_output_put(handle, nr); | |
6252 | } | |
6253 | } | |
4018994f JO |
6254 | |
6255 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6256 | u64 abi = data->regs_user.abi; | |
6257 | ||
6258 | /* | |
6259 | * If there are no regs to dump, notice it through | |
6260 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6261 | */ | |
6262 | perf_output_put(handle, abi); | |
6263 | ||
6264 | if (abi) { | |
6265 | u64 mask = event->attr.sample_regs_user; | |
6266 | perf_output_sample_regs(handle, | |
6267 | data->regs_user.regs, | |
6268 | mask); | |
6269 | } | |
6270 | } | |
c5ebcedb | 6271 | |
a5cdd40c | 6272 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6273 | perf_output_sample_ustack(handle, |
6274 | data->stack_user_size, | |
6275 | data->regs_user.regs); | |
a5cdd40c | 6276 | } |
c3feedf2 AK |
6277 | |
6278 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6279 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6280 | |
6281 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6282 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6283 | |
fdfbbd07 AK |
6284 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6285 | perf_output_put(handle, data->txn); | |
6286 | ||
60e2364e SE |
6287 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6288 | u64 abi = data->regs_intr.abi; | |
6289 | /* | |
6290 | * If there are no regs to dump, notice it through | |
6291 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6292 | */ | |
6293 | perf_output_put(handle, abi); | |
6294 | ||
6295 | if (abi) { | |
6296 | u64 mask = event->attr.sample_regs_intr; | |
6297 | ||
6298 | perf_output_sample_regs(handle, | |
6299 | data->regs_intr.regs, | |
6300 | mask); | |
6301 | } | |
6302 | } | |
6303 | ||
fc7ce9c7 KL |
6304 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6305 | perf_output_put(handle, data->phys_addr); | |
6306 | ||
a5cdd40c PZ |
6307 | if (!event->attr.watermark) { |
6308 | int wakeup_events = event->attr.wakeup_events; | |
6309 | ||
6310 | if (wakeup_events) { | |
6311 | struct ring_buffer *rb = handle->rb; | |
6312 | int events = local_inc_return(&rb->events); | |
6313 | ||
6314 | if (events >= wakeup_events) { | |
6315 | local_sub(wakeup_events, &rb->events); | |
6316 | local_inc(&rb->wakeup); | |
6317 | } | |
6318 | } | |
6319 | } | |
5622f295 MM |
6320 | } |
6321 | ||
fc7ce9c7 KL |
6322 | static u64 perf_virt_to_phys(u64 virt) |
6323 | { | |
6324 | u64 phys_addr = 0; | |
6325 | struct page *p = NULL; | |
6326 | ||
6327 | if (!virt) | |
6328 | return 0; | |
6329 | ||
6330 | if (virt >= TASK_SIZE) { | |
6331 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6332 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6333 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6334 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6335 | } else { | |
6336 | /* | |
6337 | * Walking the pages tables for user address. | |
6338 | * Interrupts are disabled, so it prevents any tear down | |
6339 | * of the page tables. | |
6340 | * Try IRQ-safe __get_user_pages_fast first. | |
6341 | * If failed, leave phys_addr as 0. | |
6342 | */ | |
6343 | if ((current->mm != NULL) && | |
6344 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6345 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6346 | ||
6347 | if (p) | |
6348 | put_page(p); | |
6349 | } | |
6350 | ||
6351 | return phys_addr; | |
6352 | } | |
6353 | ||
99e818cc JO |
6354 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6355 | ||
6cbc304f | 6356 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6357 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6358 | { | |
6359 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6360 | bool user = !event->attr.exclude_callchain_user; | |
6361 | /* Disallow cross-task user callchains. */ | |
6362 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6363 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6364 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6365 | |
6366 | if (!kernel && !user) | |
99e818cc | 6367 | return &__empty_callchain; |
8cf7e0e2 | 6368 | |
99e818cc JO |
6369 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6370 | max_stack, crosstask, true); | |
6371 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6372 | } |
6373 | ||
5622f295 MM |
6374 | void perf_prepare_sample(struct perf_event_header *header, |
6375 | struct perf_sample_data *data, | |
cdd6c482 | 6376 | struct perf_event *event, |
5622f295 | 6377 | struct pt_regs *regs) |
7b732a75 | 6378 | { |
cdd6c482 | 6379 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6380 | |
cdd6c482 | 6381 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6382 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6383 | |
6384 | header->misc = 0; | |
6385 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6386 | |
c980d109 | 6387 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6388 | |
c320c7b7 | 6389 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6390 | data->ip = perf_instruction_pointer(regs); |
6391 | ||
b23f3325 | 6392 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6393 | int size = 1; |
394ee076 | 6394 | |
6cbc304f PZ |
6395 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6396 | data->callchain = perf_callchain(event, regs); | |
6397 | ||
99e818cc | 6398 | size += data->callchain->nr; |
5622f295 MM |
6399 | |
6400 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6401 | } |
6402 | ||
3a43ce68 | 6403 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6404 | struct perf_raw_record *raw = data->raw; |
6405 | int size; | |
6406 | ||
6407 | if (raw) { | |
6408 | struct perf_raw_frag *frag = &raw->frag; | |
6409 | u32 sum = 0; | |
6410 | ||
6411 | do { | |
6412 | sum += frag->size; | |
6413 | if (perf_raw_frag_last(frag)) | |
6414 | break; | |
6415 | frag = frag->next; | |
6416 | } while (1); | |
6417 | ||
6418 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6419 | raw->size = size - sizeof(u32); | |
6420 | frag->pad = raw->size - sum; | |
6421 | } else { | |
6422 | size = sizeof(u64); | |
6423 | } | |
a044560c | 6424 | |
7e3f977e | 6425 | header->size += size; |
7f453c24 | 6426 | } |
bce38cd5 SE |
6427 | |
6428 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6429 | int size = sizeof(u64); /* nr */ | |
6430 | if (data->br_stack) { | |
6431 | size += data->br_stack->nr | |
6432 | * sizeof(struct perf_branch_entry); | |
6433 | } | |
6434 | header->size += size; | |
6435 | } | |
4018994f | 6436 | |
2565711f | 6437 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6438 | perf_sample_regs_user(&data->regs_user, regs, |
6439 | &data->regs_user_copy); | |
2565711f | 6440 | |
4018994f JO |
6441 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6442 | /* regs dump ABI info */ | |
6443 | int size = sizeof(u64); | |
6444 | ||
4018994f JO |
6445 | if (data->regs_user.regs) { |
6446 | u64 mask = event->attr.sample_regs_user; | |
6447 | size += hweight64(mask) * sizeof(u64); | |
6448 | } | |
6449 | ||
6450 | header->size += size; | |
6451 | } | |
c5ebcedb JO |
6452 | |
6453 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6454 | /* | |
6455 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6456 | * processed as the last one or have additional check added | |
6457 | * in case new sample type is added, because we could eat | |
6458 | * up the rest of the sample size. | |
6459 | */ | |
c5ebcedb JO |
6460 | u16 stack_size = event->attr.sample_stack_user; |
6461 | u16 size = sizeof(u64); | |
6462 | ||
c5ebcedb | 6463 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6464 | data->regs_user.regs); |
c5ebcedb JO |
6465 | |
6466 | /* | |
6467 | * If there is something to dump, add space for the dump | |
6468 | * itself and for the field that tells the dynamic size, | |
6469 | * which is how many have been actually dumped. | |
6470 | */ | |
6471 | if (stack_size) | |
6472 | size += sizeof(u64) + stack_size; | |
6473 | ||
6474 | data->stack_user_size = stack_size; | |
6475 | header->size += size; | |
6476 | } | |
60e2364e SE |
6477 | |
6478 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6479 | /* regs dump ABI info */ | |
6480 | int size = sizeof(u64); | |
6481 | ||
6482 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6483 | ||
6484 | if (data->regs_intr.regs) { | |
6485 | u64 mask = event->attr.sample_regs_intr; | |
6486 | ||
6487 | size += hweight64(mask) * sizeof(u64); | |
6488 | } | |
6489 | ||
6490 | header->size += size; | |
6491 | } | |
fc7ce9c7 KL |
6492 | |
6493 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6494 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6495 | } |
7f453c24 | 6496 | |
56201969 | 6497 | static __always_inline int |
9ecda41a WN |
6498 | __perf_event_output(struct perf_event *event, |
6499 | struct perf_sample_data *data, | |
6500 | struct pt_regs *regs, | |
6501 | int (*output_begin)(struct perf_output_handle *, | |
6502 | struct perf_event *, | |
6503 | unsigned int)) | |
5622f295 MM |
6504 | { |
6505 | struct perf_output_handle handle; | |
6506 | struct perf_event_header header; | |
56201969 | 6507 | int err; |
689802b2 | 6508 | |
927c7a9e FW |
6509 | /* protect the callchain buffers */ |
6510 | rcu_read_lock(); | |
6511 | ||
cdd6c482 | 6512 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6513 | |
56201969 ACM |
6514 | err = output_begin(&handle, event, header.size); |
6515 | if (err) | |
927c7a9e | 6516 | goto exit; |
0322cd6e | 6517 | |
cdd6c482 | 6518 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6519 | |
8a057d84 | 6520 | perf_output_end(&handle); |
927c7a9e FW |
6521 | |
6522 | exit: | |
6523 | rcu_read_unlock(); | |
56201969 | 6524 | return err; |
0322cd6e PZ |
6525 | } |
6526 | ||
9ecda41a WN |
6527 | void |
6528 | perf_event_output_forward(struct perf_event *event, | |
6529 | struct perf_sample_data *data, | |
6530 | struct pt_regs *regs) | |
6531 | { | |
6532 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6533 | } | |
6534 | ||
6535 | void | |
6536 | perf_event_output_backward(struct perf_event *event, | |
6537 | struct perf_sample_data *data, | |
6538 | struct pt_regs *regs) | |
6539 | { | |
6540 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6541 | } | |
6542 | ||
56201969 | 6543 | int |
9ecda41a WN |
6544 | perf_event_output(struct perf_event *event, |
6545 | struct perf_sample_data *data, | |
6546 | struct pt_regs *regs) | |
6547 | { | |
56201969 | 6548 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
6549 | } |
6550 | ||
38b200d6 | 6551 | /* |
cdd6c482 | 6552 | * read event_id |
38b200d6 PZ |
6553 | */ |
6554 | ||
6555 | struct perf_read_event { | |
6556 | struct perf_event_header header; | |
6557 | ||
6558 | u32 pid; | |
6559 | u32 tid; | |
38b200d6 PZ |
6560 | }; |
6561 | ||
6562 | static void | |
cdd6c482 | 6563 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6564 | struct task_struct *task) |
6565 | { | |
6566 | struct perf_output_handle handle; | |
c980d109 | 6567 | struct perf_sample_data sample; |
dfc65094 | 6568 | struct perf_read_event read_event = { |
38b200d6 | 6569 | .header = { |
cdd6c482 | 6570 | .type = PERF_RECORD_READ, |
38b200d6 | 6571 | .misc = 0, |
c320c7b7 | 6572 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6573 | }, |
cdd6c482 IM |
6574 | .pid = perf_event_pid(event, task), |
6575 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6576 | }; |
3dab77fb | 6577 | int ret; |
38b200d6 | 6578 | |
c980d109 | 6579 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6580 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6581 | if (ret) |
6582 | return; | |
6583 | ||
dfc65094 | 6584 | perf_output_put(&handle, read_event); |
cdd6c482 | 6585 | perf_output_read(&handle, event); |
c980d109 | 6586 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6587 | |
38b200d6 PZ |
6588 | perf_output_end(&handle); |
6589 | } | |
6590 | ||
aab5b71e | 6591 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6592 | |
6593 | static void | |
aab5b71e PZ |
6594 | perf_iterate_ctx(struct perf_event_context *ctx, |
6595 | perf_iterate_f output, | |
b73e4fef | 6596 | void *data, bool all) |
52d857a8 JO |
6597 | { |
6598 | struct perf_event *event; | |
6599 | ||
6600 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6601 | if (!all) { |
6602 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6603 | continue; | |
6604 | if (!event_filter_match(event)) | |
6605 | continue; | |
6606 | } | |
6607 | ||
67516844 | 6608 | output(event, data); |
52d857a8 JO |
6609 | } |
6610 | } | |
6611 | ||
aab5b71e | 6612 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6613 | { |
6614 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6615 | struct perf_event *event; | |
6616 | ||
6617 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6618 | /* |
6619 | * Skip events that are not fully formed yet; ensure that | |
6620 | * if we observe event->ctx, both event and ctx will be | |
6621 | * complete enough. See perf_install_in_context(). | |
6622 | */ | |
6623 | if (!smp_load_acquire(&event->ctx)) | |
6624 | continue; | |
6625 | ||
f2fb6bef KL |
6626 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6627 | continue; | |
6628 | if (!event_filter_match(event)) | |
6629 | continue; | |
6630 | output(event, data); | |
6631 | } | |
6632 | } | |
6633 | ||
aab5b71e PZ |
6634 | /* |
6635 | * Iterate all events that need to receive side-band events. | |
6636 | * | |
6637 | * For new callers; ensure that account_pmu_sb_event() includes | |
6638 | * your event, otherwise it might not get delivered. | |
6639 | */ | |
52d857a8 | 6640 | static void |
aab5b71e | 6641 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6642 | struct perf_event_context *task_ctx) |
6643 | { | |
52d857a8 | 6644 | struct perf_event_context *ctx; |
52d857a8 JO |
6645 | int ctxn; |
6646 | ||
aab5b71e PZ |
6647 | rcu_read_lock(); |
6648 | preempt_disable(); | |
6649 | ||
4e93ad60 | 6650 | /* |
aab5b71e PZ |
6651 | * If we have task_ctx != NULL we only notify the task context itself. |
6652 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6653 | * context. |
6654 | */ | |
6655 | if (task_ctx) { | |
aab5b71e PZ |
6656 | perf_iterate_ctx(task_ctx, output, data, false); |
6657 | goto done; | |
4e93ad60 JO |
6658 | } |
6659 | ||
aab5b71e | 6660 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6661 | |
6662 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6663 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6664 | if (ctx) | |
aab5b71e | 6665 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6666 | } |
aab5b71e | 6667 | done: |
f2fb6bef | 6668 | preempt_enable(); |
52d857a8 | 6669 | rcu_read_unlock(); |
95ff4ca2 AS |
6670 | } |
6671 | ||
375637bc AS |
6672 | /* |
6673 | * Clear all file-based filters at exec, they'll have to be | |
6674 | * re-instated when/if these objects are mmapped again. | |
6675 | */ | |
6676 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6677 | { | |
6678 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6679 | struct perf_addr_filter *filter; | |
6680 | unsigned int restart = 0, count = 0; | |
6681 | unsigned long flags; | |
6682 | ||
6683 | if (!has_addr_filter(event)) | |
6684 | return; | |
6685 | ||
6686 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6687 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 6688 | if (filter->path.dentry) { |
375637bc AS |
6689 | event->addr_filters_offs[count] = 0; |
6690 | restart++; | |
6691 | } | |
6692 | ||
6693 | count++; | |
6694 | } | |
6695 | ||
6696 | if (restart) | |
6697 | event->addr_filters_gen++; | |
6698 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6699 | ||
6700 | if (restart) | |
767ae086 | 6701 | perf_event_stop(event, 1); |
375637bc AS |
6702 | } |
6703 | ||
6704 | void perf_event_exec(void) | |
6705 | { | |
6706 | struct perf_event_context *ctx; | |
6707 | int ctxn; | |
6708 | ||
6709 | rcu_read_lock(); | |
6710 | for_each_task_context_nr(ctxn) { | |
6711 | ctx = current->perf_event_ctxp[ctxn]; | |
6712 | if (!ctx) | |
6713 | continue; | |
6714 | ||
6715 | perf_event_enable_on_exec(ctxn); | |
6716 | ||
aab5b71e | 6717 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6718 | true); |
6719 | } | |
6720 | rcu_read_unlock(); | |
6721 | } | |
6722 | ||
95ff4ca2 AS |
6723 | struct remote_output { |
6724 | struct ring_buffer *rb; | |
6725 | int err; | |
6726 | }; | |
6727 | ||
6728 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6729 | { | |
6730 | struct perf_event *parent = event->parent; | |
6731 | struct remote_output *ro = data; | |
6732 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6733 | struct stop_event_data sd = { |
6734 | .event = event, | |
6735 | }; | |
95ff4ca2 AS |
6736 | |
6737 | if (!has_aux(event)) | |
6738 | return; | |
6739 | ||
6740 | if (!parent) | |
6741 | parent = event; | |
6742 | ||
6743 | /* | |
6744 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6745 | * ring-buffer, but it will be the child that's actually using it. |
6746 | * | |
6747 | * We are using event::rb to determine if the event should be stopped, | |
6748 | * however this may race with ring_buffer_attach() (through set_output), | |
6749 | * which will make us skip the event that actually needs to be stopped. | |
6750 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6751 | * its rb pointer. | |
95ff4ca2 AS |
6752 | */ |
6753 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6754 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6755 | } |
6756 | ||
6757 | static int __perf_pmu_output_stop(void *info) | |
6758 | { | |
6759 | struct perf_event *event = info; | |
6760 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6761 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6762 | struct remote_output ro = { |
6763 | .rb = event->rb, | |
6764 | }; | |
6765 | ||
6766 | rcu_read_lock(); | |
aab5b71e | 6767 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6768 | if (cpuctx->task_ctx) |
aab5b71e | 6769 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6770 | &ro, false); |
95ff4ca2 AS |
6771 | rcu_read_unlock(); |
6772 | ||
6773 | return ro.err; | |
6774 | } | |
6775 | ||
6776 | static void perf_pmu_output_stop(struct perf_event *event) | |
6777 | { | |
6778 | struct perf_event *iter; | |
6779 | int err, cpu; | |
6780 | ||
6781 | restart: | |
6782 | rcu_read_lock(); | |
6783 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6784 | /* | |
6785 | * For per-CPU events, we need to make sure that neither they | |
6786 | * nor their children are running; for cpu==-1 events it's | |
6787 | * sufficient to stop the event itself if it's active, since | |
6788 | * it can't have children. | |
6789 | */ | |
6790 | cpu = iter->cpu; | |
6791 | if (cpu == -1) | |
6792 | cpu = READ_ONCE(iter->oncpu); | |
6793 | ||
6794 | if (cpu == -1) | |
6795 | continue; | |
6796 | ||
6797 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6798 | if (err == -EAGAIN) { | |
6799 | rcu_read_unlock(); | |
6800 | goto restart; | |
6801 | } | |
6802 | } | |
6803 | rcu_read_unlock(); | |
52d857a8 JO |
6804 | } |
6805 | ||
60313ebe | 6806 | /* |
9f498cc5 PZ |
6807 | * task tracking -- fork/exit |
6808 | * | |
13d7a241 | 6809 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6810 | */ |
6811 | ||
9f498cc5 | 6812 | struct perf_task_event { |
3a80b4a3 | 6813 | struct task_struct *task; |
cdd6c482 | 6814 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6815 | |
6816 | struct { | |
6817 | struct perf_event_header header; | |
6818 | ||
6819 | u32 pid; | |
6820 | u32 ppid; | |
9f498cc5 PZ |
6821 | u32 tid; |
6822 | u32 ptid; | |
393b2ad8 | 6823 | u64 time; |
cdd6c482 | 6824 | } event_id; |
60313ebe PZ |
6825 | }; |
6826 | ||
67516844 JO |
6827 | static int perf_event_task_match(struct perf_event *event) |
6828 | { | |
13d7a241 SE |
6829 | return event->attr.comm || event->attr.mmap || |
6830 | event->attr.mmap2 || event->attr.mmap_data || | |
6831 | event->attr.task; | |
67516844 JO |
6832 | } |
6833 | ||
cdd6c482 | 6834 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6835 | void *data) |
60313ebe | 6836 | { |
52d857a8 | 6837 | struct perf_task_event *task_event = data; |
60313ebe | 6838 | struct perf_output_handle handle; |
c980d109 | 6839 | struct perf_sample_data sample; |
9f498cc5 | 6840 | struct task_struct *task = task_event->task; |
c980d109 | 6841 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6842 | |
67516844 JO |
6843 | if (!perf_event_task_match(event)) |
6844 | return; | |
6845 | ||
c980d109 | 6846 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6847 | |
c980d109 | 6848 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6849 | task_event->event_id.header.size); |
ef60777c | 6850 | if (ret) |
c980d109 | 6851 | goto out; |
60313ebe | 6852 | |
cdd6c482 IM |
6853 | task_event->event_id.pid = perf_event_pid(event, task); |
6854 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6855 | |
cdd6c482 IM |
6856 | task_event->event_id.tid = perf_event_tid(event, task); |
6857 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6858 | |
34f43927 PZ |
6859 | task_event->event_id.time = perf_event_clock(event); |
6860 | ||
cdd6c482 | 6861 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6862 | |
c980d109 ACM |
6863 | perf_event__output_id_sample(event, &handle, &sample); |
6864 | ||
60313ebe | 6865 | perf_output_end(&handle); |
c980d109 ACM |
6866 | out: |
6867 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6868 | } |
6869 | ||
cdd6c482 IM |
6870 | static void perf_event_task(struct task_struct *task, |
6871 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6872 | int new) |
60313ebe | 6873 | { |
9f498cc5 | 6874 | struct perf_task_event task_event; |
60313ebe | 6875 | |
cdd6c482 IM |
6876 | if (!atomic_read(&nr_comm_events) && |
6877 | !atomic_read(&nr_mmap_events) && | |
6878 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6879 | return; |
6880 | ||
9f498cc5 | 6881 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6882 | .task = task, |
6883 | .task_ctx = task_ctx, | |
cdd6c482 | 6884 | .event_id = { |
60313ebe | 6885 | .header = { |
cdd6c482 | 6886 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6887 | .misc = 0, |
cdd6c482 | 6888 | .size = sizeof(task_event.event_id), |
60313ebe | 6889 | }, |
573402db PZ |
6890 | /* .pid */ |
6891 | /* .ppid */ | |
9f498cc5 PZ |
6892 | /* .tid */ |
6893 | /* .ptid */ | |
34f43927 | 6894 | /* .time */ |
60313ebe PZ |
6895 | }, |
6896 | }; | |
6897 | ||
aab5b71e | 6898 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6899 | &task_event, |
6900 | task_ctx); | |
9f498cc5 PZ |
6901 | } |
6902 | ||
cdd6c482 | 6903 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6904 | { |
cdd6c482 | 6905 | perf_event_task(task, NULL, 1); |
e4222673 | 6906 | perf_event_namespaces(task); |
60313ebe PZ |
6907 | } |
6908 | ||
8d1b2d93 PZ |
6909 | /* |
6910 | * comm tracking | |
6911 | */ | |
6912 | ||
6913 | struct perf_comm_event { | |
22a4f650 IM |
6914 | struct task_struct *task; |
6915 | char *comm; | |
8d1b2d93 PZ |
6916 | int comm_size; |
6917 | ||
6918 | struct { | |
6919 | struct perf_event_header header; | |
6920 | ||
6921 | u32 pid; | |
6922 | u32 tid; | |
cdd6c482 | 6923 | } event_id; |
8d1b2d93 PZ |
6924 | }; |
6925 | ||
67516844 JO |
6926 | static int perf_event_comm_match(struct perf_event *event) |
6927 | { | |
6928 | return event->attr.comm; | |
6929 | } | |
6930 | ||
cdd6c482 | 6931 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6932 | void *data) |
8d1b2d93 | 6933 | { |
52d857a8 | 6934 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6935 | struct perf_output_handle handle; |
c980d109 | 6936 | struct perf_sample_data sample; |
cdd6c482 | 6937 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6938 | int ret; |
6939 | ||
67516844 JO |
6940 | if (!perf_event_comm_match(event)) |
6941 | return; | |
6942 | ||
c980d109 ACM |
6943 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6944 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6945 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6946 | |
6947 | if (ret) | |
c980d109 | 6948 | goto out; |
8d1b2d93 | 6949 | |
cdd6c482 IM |
6950 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6951 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6952 | |
cdd6c482 | 6953 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6954 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6955 | comm_event->comm_size); |
c980d109 ACM |
6956 | |
6957 | perf_event__output_id_sample(event, &handle, &sample); | |
6958 | ||
8d1b2d93 | 6959 | perf_output_end(&handle); |
c980d109 ACM |
6960 | out: |
6961 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6962 | } |
6963 | ||
cdd6c482 | 6964 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6965 | { |
413ee3b4 | 6966 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6967 | unsigned int size; |
8d1b2d93 | 6968 | |
413ee3b4 | 6969 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6970 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6971 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6972 | |
6973 | comm_event->comm = comm; | |
6974 | comm_event->comm_size = size; | |
6975 | ||
cdd6c482 | 6976 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6977 | |
aab5b71e | 6978 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6979 | comm_event, |
6980 | NULL); | |
8d1b2d93 PZ |
6981 | } |
6982 | ||
82b89778 | 6983 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6984 | { |
9ee318a7 PZ |
6985 | struct perf_comm_event comm_event; |
6986 | ||
cdd6c482 | 6987 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6988 | return; |
a63eaf34 | 6989 | |
9ee318a7 | 6990 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6991 | .task = task, |
573402db PZ |
6992 | /* .comm */ |
6993 | /* .comm_size */ | |
cdd6c482 | 6994 | .event_id = { |
573402db | 6995 | .header = { |
cdd6c482 | 6996 | .type = PERF_RECORD_COMM, |
82b89778 | 6997 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6998 | /* .size */ |
6999 | }, | |
7000 | /* .pid */ | |
7001 | /* .tid */ | |
8d1b2d93 PZ |
7002 | }, |
7003 | }; | |
7004 | ||
cdd6c482 | 7005 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7006 | } |
7007 | ||
e4222673 HB |
7008 | /* |
7009 | * namespaces tracking | |
7010 | */ | |
7011 | ||
7012 | struct perf_namespaces_event { | |
7013 | struct task_struct *task; | |
7014 | ||
7015 | struct { | |
7016 | struct perf_event_header header; | |
7017 | ||
7018 | u32 pid; | |
7019 | u32 tid; | |
7020 | u64 nr_namespaces; | |
7021 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7022 | } event_id; | |
7023 | }; | |
7024 | ||
7025 | static int perf_event_namespaces_match(struct perf_event *event) | |
7026 | { | |
7027 | return event->attr.namespaces; | |
7028 | } | |
7029 | ||
7030 | static void perf_event_namespaces_output(struct perf_event *event, | |
7031 | void *data) | |
7032 | { | |
7033 | struct perf_namespaces_event *namespaces_event = data; | |
7034 | struct perf_output_handle handle; | |
7035 | struct perf_sample_data sample; | |
34900ec5 | 7036 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7037 | int ret; |
7038 | ||
7039 | if (!perf_event_namespaces_match(event)) | |
7040 | return; | |
7041 | ||
7042 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7043 | &sample, event); | |
7044 | ret = perf_output_begin(&handle, event, | |
7045 | namespaces_event->event_id.header.size); | |
7046 | if (ret) | |
34900ec5 | 7047 | goto out; |
e4222673 HB |
7048 | |
7049 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7050 | namespaces_event->task); | |
7051 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7052 | namespaces_event->task); | |
7053 | ||
7054 | perf_output_put(&handle, namespaces_event->event_id); | |
7055 | ||
7056 | perf_event__output_id_sample(event, &handle, &sample); | |
7057 | ||
7058 | perf_output_end(&handle); | |
34900ec5 JO |
7059 | out: |
7060 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7061 | } |
7062 | ||
7063 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7064 | struct task_struct *task, | |
7065 | const struct proc_ns_operations *ns_ops) | |
7066 | { | |
7067 | struct path ns_path; | |
7068 | struct inode *ns_inode; | |
7069 | void *error; | |
7070 | ||
7071 | error = ns_get_path(&ns_path, task, ns_ops); | |
7072 | if (!error) { | |
7073 | ns_inode = ns_path.dentry->d_inode; | |
7074 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7075 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7076 | path_put(&ns_path); |
e4222673 HB |
7077 | } |
7078 | } | |
7079 | ||
7080 | void perf_event_namespaces(struct task_struct *task) | |
7081 | { | |
7082 | struct perf_namespaces_event namespaces_event; | |
7083 | struct perf_ns_link_info *ns_link_info; | |
7084 | ||
7085 | if (!atomic_read(&nr_namespaces_events)) | |
7086 | return; | |
7087 | ||
7088 | namespaces_event = (struct perf_namespaces_event){ | |
7089 | .task = task, | |
7090 | .event_id = { | |
7091 | .header = { | |
7092 | .type = PERF_RECORD_NAMESPACES, | |
7093 | .misc = 0, | |
7094 | .size = sizeof(namespaces_event.event_id), | |
7095 | }, | |
7096 | /* .pid */ | |
7097 | /* .tid */ | |
7098 | .nr_namespaces = NR_NAMESPACES, | |
7099 | /* .link_info[NR_NAMESPACES] */ | |
7100 | }, | |
7101 | }; | |
7102 | ||
7103 | ns_link_info = namespaces_event.event_id.link_info; | |
7104 | ||
7105 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7106 | task, &mntns_operations); | |
7107 | ||
7108 | #ifdef CONFIG_USER_NS | |
7109 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7110 | task, &userns_operations); | |
7111 | #endif | |
7112 | #ifdef CONFIG_NET_NS | |
7113 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7114 | task, &netns_operations); | |
7115 | #endif | |
7116 | #ifdef CONFIG_UTS_NS | |
7117 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7118 | task, &utsns_operations); | |
7119 | #endif | |
7120 | #ifdef CONFIG_IPC_NS | |
7121 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7122 | task, &ipcns_operations); | |
7123 | #endif | |
7124 | #ifdef CONFIG_PID_NS | |
7125 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7126 | task, &pidns_operations); | |
7127 | #endif | |
7128 | #ifdef CONFIG_CGROUPS | |
7129 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7130 | task, &cgroupns_operations); | |
7131 | #endif | |
7132 | ||
7133 | perf_iterate_sb(perf_event_namespaces_output, | |
7134 | &namespaces_event, | |
7135 | NULL); | |
7136 | } | |
7137 | ||
0a4a9391 PZ |
7138 | /* |
7139 | * mmap tracking | |
7140 | */ | |
7141 | ||
7142 | struct perf_mmap_event { | |
089dd79d PZ |
7143 | struct vm_area_struct *vma; |
7144 | ||
7145 | const char *file_name; | |
7146 | int file_size; | |
13d7a241 SE |
7147 | int maj, min; |
7148 | u64 ino; | |
7149 | u64 ino_generation; | |
f972eb63 | 7150 | u32 prot, flags; |
0a4a9391 PZ |
7151 | |
7152 | struct { | |
7153 | struct perf_event_header header; | |
7154 | ||
7155 | u32 pid; | |
7156 | u32 tid; | |
7157 | u64 start; | |
7158 | u64 len; | |
7159 | u64 pgoff; | |
cdd6c482 | 7160 | } event_id; |
0a4a9391 PZ |
7161 | }; |
7162 | ||
67516844 JO |
7163 | static int perf_event_mmap_match(struct perf_event *event, |
7164 | void *data) | |
7165 | { | |
7166 | struct perf_mmap_event *mmap_event = data; | |
7167 | struct vm_area_struct *vma = mmap_event->vma; | |
7168 | int executable = vma->vm_flags & VM_EXEC; | |
7169 | ||
7170 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7171 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7172 | } |
7173 | ||
cdd6c482 | 7174 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7175 | void *data) |
0a4a9391 | 7176 | { |
52d857a8 | 7177 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7178 | struct perf_output_handle handle; |
c980d109 | 7179 | struct perf_sample_data sample; |
cdd6c482 | 7180 | int size = mmap_event->event_id.header.size; |
c980d109 | 7181 | int ret; |
0a4a9391 | 7182 | |
67516844 JO |
7183 | if (!perf_event_mmap_match(event, data)) |
7184 | return; | |
7185 | ||
13d7a241 SE |
7186 | if (event->attr.mmap2) { |
7187 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7188 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7189 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7190 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7191 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7192 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7193 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7194 | } |
7195 | ||
c980d109 ACM |
7196 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7197 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7198 | mmap_event->event_id.header.size); |
0a4a9391 | 7199 | if (ret) |
c980d109 | 7200 | goto out; |
0a4a9391 | 7201 | |
cdd6c482 IM |
7202 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7203 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7204 | |
cdd6c482 | 7205 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7206 | |
7207 | if (event->attr.mmap2) { | |
7208 | perf_output_put(&handle, mmap_event->maj); | |
7209 | perf_output_put(&handle, mmap_event->min); | |
7210 | perf_output_put(&handle, mmap_event->ino); | |
7211 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7212 | perf_output_put(&handle, mmap_event->prot); |
7213 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7214 | } |
7215 | ||
76369139 | 7216 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7217 | mmap_event->file_size); |
c980d109 ACM |
7218 | |
7219 | perf_event__output_id_sample(event, &handle, &sample); | |
7220 | ||
78d613eb | 7221 | perf_output_end(&handle); |
c980d109 ACM |
7222 | out: |
7223 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
7224 | } |
7225 | ||
cdd6c482 | 7226 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7227 | { |
089dd79d PZ |
7228 | struct vm_area_struct *vma = mmap_event->vma; |
7229 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7230 | int maj = 0, min = 0; |
7231 | u64 ino = 0, gen = 0; | |
f972eb63 | 7232 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7233 | unsigned int size; |
7234 | char tmp[16]; | |
7235 | char *buf = NULL; | |
2c42cfbf | 7236 | char *name; |
413ee3b4 | 7237 | |
0b3589be PZ |
7238 | if (vma->vm_flags & VM_READ) |
7239 | prot |= PROT_READ; | |
7240 | if (vma->vm_flags & VM_WRITE) | |
7241 | prot |= PROT_WRITE; | |
7242 | if (vma->vm_flags & VM_EXEC) | |
7243 | prot |= PROT_EXEC; | |
7244 | ||
7245 | if (vma->vm_flags & VM_MAYSHARE) | |
7246 | flags = MAP_SHARED; | |
7247 | else | |
7248 | flags = MAP_PRIVATE; | |
7249 | ||
7250 | if (vma->vm_flags & VM_DENYWRITE) | |
7251 | flags |= MAP_DENYWRITE; | |
7252 | if (vma->vm_flags & VM_MAYEXEC) | |
7253 | flags |= MAP_EXECUTABLE; | |
7254 | if (vma->vm_flags & VM_LOCKED) | |
7255 | flags |= MAP_LOCKED; | |
7256 | if (vma->vm_flags & VM_HUGETLB) | |
7257 | flags |= MAP_HUGETLB; | |
7258 | ||
0a4a9391 | 7259 | if (file) { |
13d7a241 SE |
7260 | struct inode *inode; |
7261 | dev_t dev; | |
3ea2f2b9 | 7262 | |
2c42cfbf | 7263 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7264 | if (!buf) { |
c7e548b4 ON |
7265 | name = "//enomem"; |
7266 | goto cpy_name; | |
0a4a9391 | 7267 | } |
413ee3b4 | 7268 | /* |
3ea2f2b9 | 7269 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7270 | * need to add enough zero bytes after the string to handle |
7271 | * the 64bit alignment we do later. | |
7272 | */ | |
9bf39ab2 | 7273 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7274 | if (IS_ERR(name)) { |
c7e548b4 ON |
7275 | name = "//toolong"; |
7276 | goto cpy_name; | |
0a4a9391 | 7277 | } |
13d7a241 SE |
7278 | inode = file_inode(vma->vm_file); |
7279 | dev = inode->i_sb->s_dev; | |
7280 | ino = inode->i_ino; | |
7281 | gen = inode->i_generation; | |
7282 | maj = MAJOR(dev); | |
7283 | min = MINOR(dev); | |
f972eb63 | 7284 | |
c7e548b4 | 7285 | goto got_name; |
0a4a9391 | 7286 | } else { |
fbe26abe JO |
7287 | if (vma->vm_ops && vma->vm_ops->name) { |
7288 | name = (char *) vma->vm_ops->name(vma); | |
7289 | if (name) | |
7290 | goto cpy_name; | |
7291 | } | |
7292 | ||
2c42cfbf | 7293 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7294 | if (name) |
7295 | goto cpy_name; | |
089dd79d | 7296 | |
32c5fb7e | 7297 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7298 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7299 | name = "[heap]"; |
7300 | goto cpy_name; | |
32c5fb7e ON |
7301 | } |
7302 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7303 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7304 | name = "[stack]"; |
7305 | goto cpy_name; | |
089dd79d PZ |
7306 | } |
7307 | ||
c7e548b4 ON |
7308 | name = "//anon"; |
7309 | goto cpy_name; | |
0a4a9391 PZ |
7310 | } |
7311 | ||
c7e548b4 ON |
7312 | cpy_name: |
7313 | strlcpy(tmp, name, sizeof(tmp)); | |
7314 | name = tmp; | |
0a4a9391 | 7315 | got_name: |
2c42cfbf PZ |
7316 | /* |
7317 | * Since our buffer works in 8 byte units we need to align our string | |
7318 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7319 | * zero'd out to avoid leaking random bits to userspace. | |
7320 | */ | |
7321 | size = strlen(name)+1; | |
7322 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7323 | name[size++] = '\0'; | |
0a4a9391 PZ |
7324 | |
7325 | mmap_event->file_name = name; | |
7326 | mmap_event->file_size = size; | |
13d7a241 SE |
7327 | mmap_event->maj = maj; |
7328 | mmap_event->min = min; | |
7329 | mmap_event->ino = ino; | |
7330 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7331 | mmap_event->prot = prot; |
7332 | mmap_event->flags = flags; | |
0a4a9391 | 7333 | |
2fe85427 SE |
7334 | if (!(vma->vm_flags & VM_EXEC)) |
7335 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7336 | ||
cdd6c482 | 7337 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7338 | |
aab5b71e | 7339 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7340 | mmap_event, |
7341 | NULL); | |
665c2142 | 7342 | |
0a4a9391 PZ |
7343 | kfree(buf); |
7344 | } | |
7345 | ||
375637bc AS |
7346 | /* |
7347 | * Check whether inode and address range match filter criteria. | |
7348 | */ | |
7349 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7350 | struct file *file, unsigned long offset, | |
7351 | unsigned long size) | |
7352 | { | |
7f635ff1 MP |
7353 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7354 | if (!filter->path.dentry) | |
7355 | return false; | |
7356 | ||
9511bce9 | 7357 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7358 | return false; |
7359 | ||
7360 | if (filter->offset > offset + size) | |
7361 | return false; | |
7362 | ||
7363 | if (filter->offset + filter->size < offset) | |
7364 | return false; | |
7365 | ||
7366 | return true; | |
7367 | } | |
7368 | ||
7369 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
7370 | { | |
7371 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7372 | struct vm_area_struct *vma = data; | |
7373 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
7374 | struct file *file = vma->vm_file; | |
7375 | struct perf_addr_filter *filter; | |
7376 | unsigned int restart = 0, count = 0; | |
7377 | ||
7378 | if (!has_addr_filter(event)) | |
7379 | return; | |
7380 | ||
7381 | if (!file) | |
7382 | return; | |
7383 | ||
7384 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7385 | list_for_each_entry(filter, &ifh->list, entry) { | |
7386 | if (perf_addr_filter_match(filter, file, off, | |
7387 | vma->vm_end - vma->vm_start)) { | |
7388 | event->addr_filters_offs[count] = vma->vm_start; | |
7389 | restart++; | |
7390 | } | |
7391 | ||
7392 | count++; | |
7393 | } | |
7394 | ||
7395 | if (restart) | |
7396 | event->addr_filters_gen++; | |
7397 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7398 | ||
7399 | if (restart) | |
767ae086 | 7400 | perf_event_stop(event, 1); |
375637bc AS |
7401 | } |
7402 | ||
7403 | /* | |
7404 | * Adjust all task's events' filters to the new vma | |
7405 | */ | |
7406 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7407 | { | |
7408 | struct perf_event_context *ctx; | |
7409 | int ctxn; | |
7410 | ||
12b40a23 MP |
7411 | /* |
7412 | * Data tracing isn't supported yet and as such there is no need | |
7413 | * to keep track of anything that isn't related to executable code: | |
7414 | */ | |
7415 | if (!(vma->vm_flags & VM_EXEC)) | |
7416 | return; | |
7417 | ||
375637bc AS |
7418 | rcu_read_lock(); |
7419 | for_each_task_context_nr(ctxn) { | |
7420 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7421 | if (!ctx) | |
7422 | continue; | |
7423 | ||
aab5b71e | 7424 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7425 | } |
7426 | rcu_read_unlock(); | |
7427 | } | |
7428 | ||
3af9e859 | 7429 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7430 | { |
9ee318a7 PZ |
7431 | struct perf_mmap_event mmap_event; |
7432 | ||
cdd6c482 | 7433 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7434 | return; |
7435 | ||
7436 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7437 | .vma = vma, |
573402db PZ |
7438 | /* .file_name */ |
7439 | /* .file_size */ | |
cdd6c482 | 7440 | .event_id = { |
573402db | 7441 | .header = { |
cdd6c482 | 7442 | .type = PERF_RECORD_MMAP, |
39447b38 | 7443 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7444 | /* .size */ |
7445 | }, | |
7446 | /* .pid */ | |
7447 | /* .tid */ | |
089dd79d PZ |
7448 | .start = vma->vm_start, |
7449 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7450 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7451 | }, |
13d7a241 SE |
7452 | /* .maj (attr_mmap2 only) */ |
7453 | /* .min (attr_mmap2 only) */ | |
7454 | /* .ino (attr_mmap2 only) */ | |
7455 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7456 | /* .prot (attr_mmap2 only) */ |
7457 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7458 | }; |
7459 | ||
375637bc | 7460 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7461 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7462 | } |
7463 | ||
68db7e98 AS |
7464 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7465 | unsigned long size, u64 flags) | |
7466 | { | |
7467 | struct perf_output_handle handle; | |
7468 | struct perf_sample_data sample; | |
7469 | struct perf_aux_event { | |
7470 | struct perf_event_header header; | |
7471 | u64 offset; | |
7472 | u64 size; | |
7473 | u64 flags; | |
7474 | } rec = { | |
7475 | .header = { | |
7476 | .type = PERF_RECORD_AUX, | |
7477 | .misc = 0, | |
7478 | .size = sizeof(rec), | |
7479 | }, | |
7480 | .offset = head, | |
7481 | .size = size, | |
7482 | .flags = flags, | |
7483 | }; | |
7484 | int ret; | |
7485 | ||
7486 | perf_event_header__init_id(&rec.header, &sample, event); | |
7487 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7488 | ||
7489 | if (ret) | |
7490 | return; | |
7491 | ||
7492 | perf_output_put(&handle, rec); | |
7493 | perf_event__output_id_sample(event, &handle, &sample); | |
7494 | ||
7495 | perf_output_end(&handle); | |
7496 | } | |
7497 | ||
f38b0dbb KL |
7498 | /* |
7499 | * Lost/dropped samples logging | |
7500 | */ | |
7501 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7502 | { | |
7503 | struct perf_output_handle handle; | |
7504 | struct perf_sample_data sample; | |
7505 | int ret; | |
7506 | ||
7507 | struct { | |
7508 | struct perf_event_header header; | |
7509 | u64 lost; | |
7510 | } lost_samples_event = { | |
7511 | .header = { | |
7512 | .type = PERF_RECORD_LOST_SAMPLES, | |
7513 | .misc = 0, | |
7514 | .size = sizeof(lost_samples_event), | |
7515 | }, | |
7516 | .lost = lost, | |
7517 | }; | |
7518 | ||
7519 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7520 | ||
7521 | ret = perf_output_begin(&handle, event, | |
7522 | lost_samples_event.header.size); | |
7523 | if (ret) | |
7524 | return; | |
7525 | ||
7526 | perf_output_put(&handle, lost_samples_event); | |
7527 | perf_event__output_id_sample(event, &handle, &sample); | |
7528 | perf_output_end(&handle); | |
7529 | } | |
7530 | ||
45ac1403 AH |
7531 | /* |
7532 | * context_switch tracking | |
7533 | */ | |
7534 | ||
7535 | struct perf_switch_event { | |
7536 | struct task_struct *task; | |
7537 | struct task_struct *next_prev; | |
7538 | ||
7539 | struct { | |
7540 | struct perf_event_header header; | |
7541 | u32 next_prev_pid; | |
7542 | u32 next_prev_tid; | |
7543 | } event_id; | |
7544 | }; | |
7545 | ||
7546 | static int perf_event_switch_match(struct perf_event *event) | |
7547 | { | |
7548 | return event->attr.context_switch; | |
7549 | } | |
7550 | ||
7551 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7552 | { | |
7553 | struct perf_switch_event *se = data; | |
7554 | struct perf_output_handle handle; | |
7555 | struct perf_sample_data sample; | |
7556 | int ret; | |
7557 | ||
7558 | if (!perf_event_switch_match(event)) | |
7559 | return; | |
7560 | ||
7561 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7562 | if (event->ctx->task) { | |
7563 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7564 | se->event_id.header.size = sizeof(se->event_id.header); | |
7565 | } else { | |
7566 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7567 | se->event_id.header.size = sizeof(se->event_id); | |
7568 | se->event_id.next_prev_pid = | |
7569 | perf_event_pid(event, se->next_prev); | |
7570 | se->event_id.next_prev_tid = | |
7571 | perf_event_tid(event, se->next_prev); | |
7572 | } | |
7573 | ||
7574 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7575 | ||
7576 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7577 | if (ret) | |
7578 | return; | |
7579 | ||
7580 | if (event->ctx->task) | |
7581 | perf_output_put(&handle, se->event_id.header); | |
7582 | else | |
7583 | perf_output_put(&handle, se->event_id); | |
7584 | ||
7585 | perf_event__output_id_sample(event, &handle, &sample); | |
7586 | ||
7587 | perf_output_end(&handle); | |
7588 | } | |
7589 | ||
7590 | static void perf_event_switch(struct task_struct *task, | |
7591 | struct task_struct *next_prev, bool sched_in) | |
7592 | { | |
7593 | struct perf_switch_event switch_event; | |
7594 | ||
7595 | /* N.B. caller checks nr_switch_events != 0 */ | |
7596 | ||
7597 | switch_event = (struct perf_switch_event){ | |
7598 | .task = task, | |
7599 | .next_prev = next_prev, | |
7600 | .event_id = { | |
7601 | .header = { | |
7602 | /* .type */ | |
7603 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7604 | /* .size */ | |
7605 | }, | |
7606 | /* .next_prev_pid */ | |
7607 | /* .next_prev_tid */ | |
7608 | }, | |
7609 | }; | |
7610 | ||
101592b4 AB |
7611 | if (!sched_in && task->state == TASK_RUNNING) |
7612 | switch_event.event_id.header.misc |= | |
7613 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
7614 | ||
aab5b71e | 7615 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7616 | &switch_event, |
7617 | NULL); | |
7618 | } | |
7619 | ||
a78ac325 PZ |
7620 | /* |
7621 | * IRQ throttle logging | |
7622 | */ | |
7623 | ||
cdd6c482 | 7624 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7625 | { |
7626 | struct perf_output_handle handle; | |
c980d109 | 7627 | struct perf_sample_data sample; |
a78ac325 PZ |
7628 | int ret; |
7629 | ||
7630 | struct { | |
7631 | struct perf_event_header header; | |
7632 | u64 time; | |
cca3f454 | 7633 | u64 id; |
7f453c24 | 7634 | u64 stream_id; |
a78ac325 PZ |
7635 | } throttle_event = { |
7636 | .header = { | |
cdd6c482 | 7637 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7638 | .misc = 0, |
7639 | .size = sizeof(throttle_event), | |
7640 | }, | |
34f43927 | 7641 | .time = perf_event_clock(event), |
cdd6c482 IM |
7642 | .id = primary_event_id(event), |
7643 | .stream_id = event->id, | |
a78ac325 PZ |
7644 | }; |
7645 | ||
966ee4d6 | 7646 | if (enable) |
cdd6c482 | 7647 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7648 | |
c980d109 ACM |
7649 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7650 | ||
7651 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7652 | throttle_event.header.size); |
a78ac325 PZ |
7653 | if (ret) |
7654 | return; | |
7655 | ||
7656 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7657 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7658 | perf_output_end(&handle); |
7659 | } | |
7660 | ||
76193a94 SL |
7661 | /* |
7662 | * ksymbol register/unregister tracking | |
7663 | */ | |
7664 | ||
7665 | struct perf_ksymbol_event { | |
7666 | const char *name; | |
7667 | int name_len; | |
7668 | struct { | |
7669 | struct perf_event_header header; | |
7670 | u64 addr; | |
7671 | u32 len; | |
7672 | u16 ksym_type; | |
7673 | u16 flags; | |
7674 | } event_id; | |
7675 | }; | |
7676 | ||
7677 | static int perf_event_ksymbol_match(struct perf_event *event) | |
7678 | { | |
7679 | return event->attr.ksymbol; | |
7680 | } | |
7681 | ||
7682 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
7683 | { | |
7684 | struct perf_ksymbol_event *ksymbol_event = data; | |
7685 | struct perf_output_handle handle; | |
7686 | struct perf_sample_data sample; | |
7687 | int ret; | |
7688 | ||
7689 | if (!perf_event_ksymbol_match(event)) | |
7690 | return; | |
7691 | ||
7692 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
7693 | &sample, event); | |
7694 | ret = perf_output_begin(&handle, event, | |
7695 | ksymbol_event->event_id.header.size); | |
7696 | if (ret) | |
7697 | return; | |
7698 | ||
7699 | perf_output_put(&handle, ksymbol_event->event_id); | |
7700 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
7701 | perf_event__output_id_sample(event, &handle, &sample); | |
7702 | ||
7703 | perf_output_end(&handle); | |
7704 | } | |
7705 | ||
7706 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
7707 | const char *sym) | |
7708 | { | |
7709 | struct perf_ksymbol_event ksymbol_event; | |
7710 | char name[KSYM_NAME_LEN]; | |
7711 | u16 flags = 0; | |
7712 | int name_len; | |
7713 | ||
7714 | if (!atomic_read(&nr_ksymbol_events)) | |
7715 | return; | |
7716 | ||
7717 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
7718 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
7719 | goto err; | |
7720 | ||
7721 | strlcpy(name, sym, KSYM_NAME_LEN); | |
7722 | name_len = strlen(name) + 1; | |
7723 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
7724 | name[name_len++] = '\0'; | |
7725 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
7726 | ||
7727 | if (unregister) | |
7728 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
7729 | ||
7730 | ksymbol_event = (struct perf_ksymbol_event){ | |
7731 | .name = name, | |
7732 | .name_len = name_len, | |
7733 | .event_id = { | |
7734 | .header = { | |
7735 | .type = PERF_RECORD_KSYMBOL, | |
7736 | .size = sizeof(ksymbol_event.event_id) + | |
7737 | name_len, | |
7738 | }, | |
7739 | .addr = addr, | |
7740 | .len = len, | |
7741 | .ksym_type = ksym_type, | |
7742 | .flags = flags, | |
7743 | }, | |
7744 | }; | |
7745 | ||
7746 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
7747 | return; | |
7748 | err: | |
7749 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
7750 | } | |
7751 | ||
6ee52e2a SL |
7752 | /* |
7753 | * bpf program load/unload tracking | |
7754 | */ | |
7755 | ||
7756 | struct perf_bpf_event { | |
7757 | struct bpf_prog *prog; | |
7758 | struct { | |
7759 | struct perf_event_header header; | |
7760 | u16 type; | |
7761 | u16 flags; | |
7762 | u32 id; | |
7763 | u8 tag[BPF_TAG_SIZE]; | |
7764 | } event_id; | |
7765 | }; | |
7766 | ||
7767 | static int perf_event_bpf_match(struct perf_event *event) | |
7768 | { | |
7769 | return event->attr.bpf_event; | |
7770 | } | |
7771 | ||
7772 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
7773 | { | |
7774 | struct perf_bpf_event *bpf_event = data; | |
7775 | struct perf_output_handle handle; | |
7776 | struct perf_sample_data sample; | |
7777 | int ret; | |
7778 | ||
7779 | if (!perf_event_bpf_match(event)) | |
7780 | return; | |
7781 | ||
7782 | perf_event_header__init_id(&bpf_event->event_id.header, | |
7783 | &sample, event); | |
7784 | ret = perf_output_begin(&handle, event, | |
7785 | bpf_event->event_id.header.size); | |
7786 | if (ret) | |
7787 | return; | |
7788 | ||
7789 | perf_output_put(&handle, bpf_event->event_id); | |
7790 | perf_event__output_id_sample(event, &handle, &sample); | |
7791 | ||
7792 | perf_output_end(&handle); | |
7793 | } | |
7794 | ||
7795 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
7796 | enum perf_bpf_event_type type) | |
7797 | { | |
7798 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
7799 | char sym[KSYM_NAME_LEN]; | |
7800 | int i; | |
7801 | ||
7802 | if (prog->aux->func_cnt == 0) { | |
7803 | bpf_get_prog_name(prog, sym); | |
7804 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
7805 | (u64)(unsigned long)prog->bpf_func, | |
7806 | prog->jited_len, unregister, sym); | |
7807 | } else { | |
7808 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
7809 | struct bpf_prog *subprog = prog->aux->func[i]; | |
7810 | ||
7811 | bpf_get_prog_name(subprog, sym); | |
7812 | perf_event_ksymbol( | |
7813 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
7814 | (u64)(unsigned long)subprog->bpf_func, | |
7815 | subprog->jited_len, unregister, sym); | |
7816 | } | |
7817 | } | |
7818 | } | |
7819 | ||
7820 | void perf_event_bpf_event(struct bpf_prog *prog, | |
7821 | enum perf_bpf_event_type type, | |
7822 | u16 flags) | |
7823 | { | |
7824 | struct perf_bpf_event bpf_event; | |
7825 | ||
7826 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
7827 | type >= PERF_BPF_EVENT_MAX) | |
7828 | return; | |
7829 | ||
7830 | switch (type) { | |
7831 | case PERF_BPF_EVENT_PROG_LOAD: | |
7832 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
7833 | if (atomic_read(&nr_ksymbol_events)) | |
7834 | perf_event_bpf_emit_ksymbols(prog, type); | |
7835 | break; | |
7836 | default: | |
7837 | break; | |
7838 | } | |
7839 | ||
7840 | if (!atomic_read(&nr_bpf_events)) | |
7841 | return; | |
7842 | ||
7843 | bpf_event = (struct perf_bpf_event){ | |
7844 | .prog = prog, | |
7845 | .event_id = { | |
7846 | .header = { | |
7847 | .type = PERF_RECORD_BPF_EVENT, | |
7848 | .size = sizeof(bpf_event.event_id), | |
7849 | }, | |
7850 | .type = type, | |
7851 | .flags = flags, | |
7852 | .id = prog->aux->id, | |
7853 | }, | |
7854 | }; | |
7855 | ||
7856 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
7857 | ||
7858 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
7859 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
7860 | } | |
7861 | ||
8d4e6c4c AS |
7862 | void perf_event_itrace_started(struct perf_event *event) |
7863 | { | |
7864 | event->attach_state |= PERF_ATTACH_ITRACE; | |
7865 | } | |
7866 | ||
ec0d7729 AS |
7867 | static void perf_log_itrace_start(struct perf_event *event) |
7868 | { | |
7869 | struct perf_output_handle handle; | |
7870 | struct perf_sample_data sample; | |
7871 | struct perf_aux_event { | |
7872 | struct perf_event_header header; | |
7873 | u32 pid; | |
7874 | u32 tid; | |
7875 | } rec; | |
7876 | int ret; | |
7877 | ||
7878 | if (event->parent) | |
7879 | event = event->parent; | |
7880 | ||
7881 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 7882 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
7883 | return; |
7884 | ||
ec0d7729 AS |
7885 | rec.header.type = PERF_RECORD_ITRACE_START; |
7886 | rec.header.misc = 0; | |
7887 | rec.header.size = sizeof(rec); | |
7888 | rec.pid = perf_event_pid(event, current); | |
7889 | rec.tid = perf_event_tid(event, current); | |
7890 | ||
7891 | perf_event_header__init_id(&rec.header, &sample, event); | |
7892 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7893 | ||
7894 | if (ret) | |
7895 | return; | |
7896 | ||
7897 | perf_output_put(&handle, rec); | |
7898 | perf_event__output_id_sample(event, &handle, &sample); | |
7899 | ||
7900 | perf_output_end(&handle); | |
7901 | } | |
7902 | ||
475113d9 JO |
7903 | static int |
7904 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7905 | { |
cdd6c482 | 7906 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7907 | int ret = 0; |
475113d9 | 7908 | u64 seq; |
96398826 | 7909 | |
e050e3f0 SE |
7910 | seq = __this_cpu_read(perf_throttled_seq); |
7911 | if (seq != hwc->interrupts_seq) { | |
7912 | hwc->interrupts_seq = seq; | |
7913 | hwc->interrupts = 1; | |
7914 | } else { | |
7915 | hwc->interrupts++; | |
7916 | if (unlikely(throttle | |
7917 | && hwc->interrupts >= max_samples_per_tick)) { | |
7918 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7919 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7920 | hwc->interrupts = MAX_INTERRUPTS; |
7921 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7922 | ret = 1; |
7923 | } | |
e050e3f0 | 7924 | } |
60db5e09 | 7925 | |
cdd6c482 | 7926 | if (event->attr.freq) { |
def0a9b2 | 7927 | u64 now = perf_clock(); |
abd50713 | 7928 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7929 | |
abd50713 | 7930 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7931 | |
abd50713 | 7932 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7933 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7934 | } |
7935 | ||
475113d9 JO |
7936 | return ret; |
7937 | } | |
7938 | ||
7939 | int perf_event_account_interrupt(struct perf_event *event) | |
7940 | { | |
7941 | return __perf_event_account_interrupt(event, 1); | |
7942 | } | |
7943 | ||
7944 | /* | |
7945 | * Generic event overflow handling, sampling. | |
7946 | */ | |
7947 | ||
7948 | static int __perf_event_overflow(struct perf_event *event, | |
7949 | int throttle, struct perf_sample_data *data, | |
7950 | struct pt_regs *regs) | |
7951 | { | |
7952 | int events = atomic_read(&event->event_limit); | |
7953 | int ret = 0; | |
7954 | ||
7955 | /* | |
7956 | * Non-sampling counters might still use the PMI to fold short | |
7957 | * hardware counters, ignore those. | |
7958 | */ | |
7959 | if (unlikely(!is_sampling_event(event))) | |
7960 | return 0; | |
7961 | ||
7962 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 7963 | |
2023b359 PZ |
7964 | /* |
7965 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7966 | * events |
2023b359 PZ |
7967 | */ |
7968 | ||
cdd6c482 IM |
7969 | event->pending_kill = POLL_IN; |
7970 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7971 | ret = 1; |
cdd6c482 | 7972 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7973 | |
7974 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7975 | } |
7976 | ||
aa6a5f3c | 7977 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7978 | |
fed66e2c | 7979 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7980 | event->pending_wakeup = 1; |
7981 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7982 | } |
7983 | ||
79f14641 | 7984 | return ret; |
f6c7d5fe PZ |
7985 | } |
7986 | ||
a8b0ca17 | 7987 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7988 | struct perf_sample_data *data, |
7989 | struct pt_regs *regs) | |
850bc73f | 7990 | { |
a8b0ca17 | 7991 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7992 | } |
7993 | ||
15dbf27c | 7994 | /* |
cdd6c482 | 7995 | * Generic software event infrastructure |
15dbf27c PZ |
7996 | */ |
7997 | ||
b28ab83c PZ |
7998 | struct swevent_htable { |
7999 | struct swevent_hlist *swevent_hlist; | |
8000 | struct mutex hlist_mutex; | |
8001 | int hlist_refcount; | |
8002 | ||
8003 | /* Recursion avoidance in each contexts */ | |
8004 | int recursion[PERF_NR_CONTEXTS]; | |
8005 | }; | |
8006 | ||
8007 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8008 | ||
7b4b6658 | 8009 | /* |
cdd6c482 IM |
8010 | * We directly increment event->count and keep a second value in |
8011 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8012 | * is kept in the range [-sample_period, 0] so that we can use the |
8013 | * sign as trigger. | |
8014 | */ | |
8015 | ||
ab573844 | 8016 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8017 | { |
cdd6c482 | 8018 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8019 | u64 period = hwc->last_period; |
8020 | u64 nr, offset; | |
8021 | s64 old, val; | |
8022 | ||
8023 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8024 | |
8025 | again: | |
e7850595 | 8026 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8027 | if (val < 0) |
8028 | return 0; | |
15dbf27c | 8029 | |
7b4b6658 PZ |
8030 | nr = div64_u64(period + val, period); |
8031 | offset = nr * period; | |
8032 | val -= offset; | |
e7850595 | 8033 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8034 | goto again; |
15dbf27c | 8035 | |
7b4b6658 | 8036 | return nr; |
15dbf27c PZ |
8037 | } |
8038 | ||
0cff784a | 8039 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8040 | struct perf_sample_data *data, |
5622f295 | 8041 | struct pt_regs *regs) |
15dbf27c | 8042 | { |
cdd6c482 | 8043 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8044 | int throttle = 0; |
15dbf27c | 8045 | |
0cff784a PZ |
8046 | if (!overflow) |
8047 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8048 | |
7b4b6658 PZ |
8049 | if (hwc->interrupts == MAX_INTERRUPTS) |
8050 | return; | |
15dbf27c | 8051 | |
7b4b6658 | 8052 | for (; overflow; overflow--) { |
a8b0ca17 | 8053 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8054 | data, regs)) { |
7b4b6658 PZ |
8055 | /* |
8056 | * We inhibit the overflow from happening when | |
8057 | * hwc->interrupts == MAX_INTERRUPTS. | |
8058 | */ | |
8059 | break; | |
8060 | } | |
cf450a73 | 8061 | throttle = 1; |
7b4b6658 | 8062 | } |
15dbf27c PZ |
8063 | } |
8064 | ||
a4eaf7f1 | 8065 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8066 | struct perf_sample_data *data, |
5622f295 | 8067 | struct pt_regs *regs) |
7b4b6658 | 8068 | { |
cdd6c482 | 8069 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8070 | |
e7850595 | 8071 | local64_add(nr, &event->count); |
d6d020e9 | 8072 | |
0cff784a PZ |
8073 | if (!regs) |
8074 | return; | |
8075 | ||
6c7e550f | 8076 | if (!is_sampling_event(event)) |
7b4b6658 | 8077 | return; |
d6d020e9 | 8078 | |
5d81e5cf AV |
8079 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8080 | data->period = nr; | |
8081 | return perf_swevent_overflow(event, 1, data, regs); | |
8082 | } else | |
8083 | data->period = event->hw.last_period; | |
8084 | ||
0cff784a | 8085 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8086 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8087 | |
e7850595 | 8088 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8089 | return; |
df1a132b | 8090 | |
a8b0ca17 | 8091 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8092 | } |
8093 | ||
f5ffe02e FW |
8094 | static int perf_exclude_event(struct perf_event *event, |
8095 | struct pt_regs *regs) | |
8096 | { | |
a4eaf7f1 | 8097 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8098 | return 1; |
a4eaf7f1 | 8099 | |
f5ffe02e FW |
8100 | if (regs) { |
8101 | if (event->attr.exclude_user && user_mode(regs)) | |
8102 | return 1; | |
8103 | ||
8104 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8105 | return 1; | |
8106 | } | |
8107 | ||
8108 | return 0; | |
8109 | } | |
8110 | ||
cdd6c482 | 8111 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8112 | enum perf_type_id type, |
6fb2915d LZ |
8113 | u32 event_id, |
8114 | struct perf_sample_data *data, | |
8115 | struct pt_regs *regs) | |
15dbf27c | 8116 | { |
cdd6c482 | 8117 | if (event->attr.type != type) |
a21ca2ca | 8118 | return 0; |
f5ffe02e | 8119 | |
cdd6c482 | 8120 | if (event->attr.config != event_id) |
15dbf27c PZ |
8121 | return 0; |
8122 | ||
f5ffe02e FW |
8123 | if (perf_exclude_event(event, regs)) |
8124 | return 0; | |
15dbf27c PZ |
8125 | |
8126 | return 1; | |
8127 | } | |
8128 | ||
76e1d904 FW |
8129 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8130 | { | |
8131 | u64 val = event_id | (type << 32); | |
8132 | ||
8133 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8134 | } | |
8135 | ||
49f135ed FW |
8136 | static inline struct hlist_head * |
8137 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8138 | { |
49f135ed FW |
8139 | u64 hash = swevent_hash(type, event_id); |
8140 | ||
8141 | return &hlist->heads[hash]; | |
8142 | } | |
76e1d904 | 8143 | |
49f135ed FW |
8144 | /* For the read side: events when they trigger */ |
8145 | static inline struct hlist_head * | |
b28ab83c | 8146 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8147 | { |
8148 | struct swevent_hlist *hlist; | |
76e1d904 | 8149 | |
b28ab83c | 8150 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8151 | if (!hlist) |
8152 | return NULL; | |
8153 | ||
49f135ed FW |
8154 | return __find_swevent_head(hlist, type, event_id); |
8155 | } | |
8156 | ||
8157 | /* For the event head insertion and removal in the hlist */ | |
8158 | static inline struct hlist_head * | |
b28ab83c | 8159 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8160 | { |
8161 | struct swevent_hlist *hlist; | |
8162 | u32 event_id = event->attr.config; | |
8163 | u64 type = event->attr.type; | |
8164 | ||
8165 | /* | |
8166 | * Event scheduling is always serialized against hlist allocation | |
8167 | * and release. Which makes the protected version suitable here. | |
8168 | * The context lock guarantees that. | |
8169 | */ | |
b28ab83c | 8170 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8171 | lockdep_is_held(&event->ctx->lock)); |
8172 | if (!hlist) | |
8173 | return NULL; | |
8174 | ||
8175 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8176 | } |
8177 | ||
8178 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8179 | u64 nr, |
76e1d904 FW |
8180 | struct perf_sample_data *data, |
8181 | struct pt_regs *regs) | |
15dbf27c | 8182 | { |
4a32fea9 | 8183 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8184 | struct perf_event *event; |
76e1d904 | 8185 | struct hlist_head *head; |
15dbf27c | 8186 | |
76e1d904 | 8187 | rcu_read_lock(); |
b28ab83c | 8188 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8189 | if (!head) |
8190 | goto end; | |
8191 | ||
b67bfe0d | 8192 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8193 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8194 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8195 | } |
76e1d904 FW |
8196 | end: |
8197 | rcu_read_unlock(); | |
15dbf27c PZ |
8198 | } |
8199 | ||
86038c5e PZI |
8200 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8201 | ||
4ed7c92d | 8202 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8203 | { |
4a32fea9 | 8204 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8205 | |
b28ab83c | 8206 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8207 | } |
645e8cc0 | 8208 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8209 | |
98b5c2c6 | 8210 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8211 | { |
4a32fea9 | 8212 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8213 | |
b28ab83c | 8214 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8215 | } |
15dbf27c | 8216 | |
86038c5e | 8217 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8218 | { |
a4234bfc | 8219 | struct perf_sample_data data; |
4ed7c92d | 8220 | |
86038c5e | 8221 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8222 | return; |
a4234bfc | 8223 | |
fd0d000b | 8224 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8225 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8226 | } |
8227 | ||
8228 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8229 | { | |
8230 | int rctx; | |
8231 | ||
8232 | preempt_disable_notrace(); | |
8233 | rctx = perf_swevent_get_recursion_context(); | |
8234 | if (unlikely(rctx < 0)) | |
8235 | goto fail; | |
8236 | ||
8237 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8238 | |
8239 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8240 | fail: |
1c024eca | 8241 | preempt_enable_notrace(); |
b8e83514 PZ |
8242 | } |
8243 | ||
cdd6c482 | 8244 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8245 | { |
15dbf27c PZ |
8246 | } |
8247 | ||
a4eaf7f1 | 8248 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8249 | { |
4a32fea9 | 8250 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8251 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8252 | struct hlist_head *head; |
8253 | ||
6c7e550f | 8254 | if (is_sampling_event(event)) { |
7b4b6658 | 8255 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8256 | perf_swevent_set_period(event); |
7b4b6658 | 8257 | } |
76e1d904 | 8258 | |
a4eaf7f1 PZ |
8259 | hwc->state = !(flags & PERF_EF_START); |
8260 | ||
b28ab83c | 8261 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8262 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8263 | return -EINVAL; |
8264 | ||
8265 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8266 | perf_event_update_userpage(event); |
76e1d904 | 8267 | |
15dbf27c PZ |
8268 | return 0; |
8269 | } | |
8270 | ||
a4eaf7f1 | 8271 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8272 | { |
76e1d904 | 8273 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8274 | } |
8275 | ||
a4eaf7f1 | 8276 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8277 | { |
a4eaf7f1 | 8278 | event->hw.state = 0; |
d6d020e9 | 8279 | } |
aa9c4c0f | 8280 | |
a4eaf7f1 | 8281 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8282 | { |
a4eaf7f1 | 8283 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8284 | } |
8285 | ||
49f135ed FW |
8286 | /* Deref the hlist from the update side */ |
8287 | static inline struct swevent_hlist * | |
b28ab83c | 8288 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8289 | { |
b28ab83c PZ |
8290 | return rcu_dereference_protected(swhash->swevent_hlist, |
8291 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8292 | } |
8293 | ||
b28ab83c | 8294 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8295 | { |
b28ab83c | 8296 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8297 | |
49f135ed | 8298 | if (!hlist) |
76e1d904 FW |
8299 | return; |
8300 | ||
70691d4a | 8301 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8302 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8303 | } |
8304 | ||
3b364d7b | 8305 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8306 | { |
b28ab83c | 8307 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8308 | |
b28ab83c | 8309 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8310 | |
b28ab83c PZ |
8311 | if (!--swhash->hlist_refcount) |
8312 | swevent_hlist_release(swhash); | |
76e1d904 | 8313 | |
b28ab83c | 8314 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8315 | } |
8316 | ||
3b364d7b | 8317 | static void swevent_hlist_put(void) |
76e1d904 FW |
8318 | { |
8319 | int cpu; | |
8320 | ||
76e1d904 | 8321 | for_each_possible_cpu(cpu) |
3b364d7b | 8322 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8323 | } |
8324 | ||
3b364d7b | 8325 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8326 | { |
b28ab83c | 8327 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8328 | int err = 0; |
8329 | ||
b28ab83c | 8330 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8331 | if (!swevent_hlist_deref(swhash) && |
8332 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8333 | struct swevent_hlist *hlist; |
8334 | ||
8335 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8336 | if (!hlist) { | |
8337 | err = -ENOMEM; | |
8338 | goto exit; | |
8339 | } | |
b28ab83c | 8340 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8341 | } |
b28ab83c | 8342 | swhash->hlist_refcount++; |
9ed6060d | 8343 | exit: |
b28ab83c | 8344 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8345 | |
8346 | return err; | |
8347 | } | |
8348 | ||
3b364d7b | 8349 | static int swevent_hlist_get(void) |
76e1d904 | 8350 | { |
3b364d7b | 8351 | int err, cpu, failed_cpu; |
76e1d904 | 8352 | |
a63fbed7 | 8353 | mutex_lock(&pmus_lock); |
76e1d904 | 8354 | for_each_possible_cpu(cpu) { |
3b364d7b | 8355 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8356 | if (err) { |
8357 | failed_cpu = cpu; | |
8358 | goto fail; | |
8359 | } | |
8360 | } | |
a63fbed7 | 8361 | mutex_unlock(&pmus_lock); |
76e1d904 | 8362 | return 0; |
9ed6060d | 8363 | fail: |
76e1d904 FW |
8364 | for_each_possible_cpu(cpu) { |
8365 | if (cpu == failed_cpu) | |
8366 | break; | |
3b364d7b | 8367 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8368 | } |
a63fbed7 | 8369 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8370 | return err; |
8371 | } | |
8372 | ||
c5905afb | 8373 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8374 | |
b0a873eb PZ |
8375 | static void sw_perf_event_destroy(struct perf_event *event) |
8376 | { | |
8377 | u64 event_id = event->attr.config; | |
95476b64 | 8378 | |
b0a873eb PZ |
8379 | WARN_ON(event->parent); |
8380 | ||
c5905afb | 8381 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8382 | swevent_hlist_put(); |
b0a873eb PZ |
8383 | } |
8384 | ||
8385 | static int perf_swevent_init(struct perf_event *event) | |
8386 | { | |
8176cced | 8387 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8388 | |
8389 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8390 | return -ENOENT; | |
8391 | ||
2481c5fa SE |
8392 | /* |
8393 | * no branch sampling for software events | |
8394 | */ | |
8395 | if (has_branch_stack(event)) | |
8396 | return -EOPNOTSUPP; | |
8397 | ||
b0a873eb PZ |
8398 | switch (event_id) { |
8399 | case PERF_COUNT_SW_CPU_CLOCK: | |
8400 | case PERF_COUNT_SW_TASK_CLOCK: | |
8401 | return -ENOENT; | |
8402 | ||
8403 | default: | |
8404 | break; | |
8405 | } | |
8406 | ||
ce677831 | 8407 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8408 | return -ENOENT; |
8409 | ||
8410 | if (!event->parent) { | |
8411 | int err; | |
8412 | ||
3b364d7b | 8413 | err = swevent_hlist_get(); |
b0a873eb PZ |
8414 | if (err) |
8415 | return err; | |
8416 | ||
c5905afb | 8417 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8418 | event->destroy = sw_perf_event_destroy; |
8419 | } | |
8420 | ||
8421 | return 0; | |
8422 | } | |
8423 | ||
8424 | static struct pmu perf_swevent = { | |
89a1e187 | 8425 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8426 | |
34f43927 PZ |
8427 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8428 | ||
b0a873eb | 8429 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8430 | .add = perf_swevent_add, |
8431 | .del = perf_swevent_del, | |
8432 | .start = perf_swevent_start, | |
8433 | .stop = perf_swevent_stop, | |
1c024eca | 8434 | .read = perf_swevent_read, |
1c024eca PZ |
8435 | }; |
8436 | ||
b0a873eb PZ |
8437 | #ifdef CONFIG_EVENT_TRACING |
8438 | ||
1c024eca PZ |
8439 | static int perf_tp_filter_match(struct perf_event *event, |
8440 | struct perf_sample_data *data) | |
8441 | { | |
7e3f977e | 8442 | void *record = data->raw->frag.data; |
1c024eca | 8443 | |
b71b437e PZ |
8444 | /* only top level events have filters set */ |
8445 | if (event->parent) | |
8446 | event = event->parent; | |
8447 | ||
1c024eca PZ |
8448 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8449 | return 1; | |
8450 | return 0; | |
8451 | } | |
8452 | ||
8453 | static int perf_tp_event_match(struct perf_event *event, | |
8454 | struct perf_sample_data *data, | |
8455 | struct pt_regs *regs) | |
8456 | { | |
a0f7d0f7 FW |
8457 | if (event->hw.state & PERF_HES_STOPPED) |
8458 | return 0; | |
580d607c PZ |
8459 | /* |
8460 | * All tracepoints are from kernel-space. | |
8461 | */ | |
8462 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
8463 | return 0; |
8464 | ||
8465 | if (!perf_tp_filter_match(event, data)) | |
8466 | return 0; | |
8467 | ||
8468 | return 1; | |
8469 | } | |
8470 | ||
85b67bcb AS |
8471 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8472 | struct trace_event_call *call, u64 count, | |
8473 | struct pt_regs *regs, struct hlist_head *head, | |
8474 | struct task_struct *task) | |
8475 | { | |
e87c6bc3 | 8476 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8477 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8478 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8479 | perf_swevent_put_recursion_context(rctx); |
8480 | return; | |
8481 | } | |
8482 | } | |
8483 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8484 | rctx, task); |
85b67bcb AS |
8485 | } |
8486 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8487 | ||
1e1dcd93 | 8488 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8489 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8490 | struct task_struct *task) |
95476b64 FW |
8491 | { |
8492 | struct perf_sample_data data; | |
8fd0fbbe | 8493 | struct perf_event *event; |
1c024eca | 8494 | |
95476b64 | 8495 | struct perf_raw_record raw = { |
7e3f977e DB |
8496 | .frag = { |
8497 | .size = entry_size, | |
8498 | .data = record, | |
8499 | }, | |
95476b64 FW |
8500 | }; |
8501 | ||
1e1dcd93 | 8502 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8503 | data.raw = &raw; |
8504 | ||
1e1dcd93 AS |
8505 | perf_trace_buf_update(record, event_type); |
8506 | ||
8fd0fbbe | 8507 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8508 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8509 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8510 | } |
ecc55f84 | 8511 | |
e6dab5ff AV |
8512 | /* |
8513 | * If we got specified a target task, also iterate its context and | |
8514 | * deliver this event there too. | |
8515 | */ | |
8516 | if (task && task != current) { | |
8517 | struct perf_event_context *ctx; | |
8518 | struct trace_entry *entry = record; | |
8519 | ||
8520 | rcu_read_lock(); | |
8521 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8522 | if (!ctx) | |
8523 | goto unlock; | |
8524 | ||
8525 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
8526 | if (event->cpu != smp_processor_id()) |
8527 | continue; | |
e6dab5ff AV |
8528 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8529 | continue; | |
8530 | if (event->attr.config != entry->type) | |
8531 | continue; | |
8532 | if (perf_tp_event_match(event, &data, regs)) | |
8533 | perf_swevent_event(event, count, &data, regs); | |
8534 | } | |
8535 | unlock: | |
8536 | rcu_read_unlock(); | |
8537 | } | |
8538 | ||
ecc55f84 | 8539 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8540 | } |
8541 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8542 | ||
cdd6c482 | 8543 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8544 | { |
1c024eca | 8545 | perf_trace_destroy(event); |
e077df4f PZ |
8546 | } |
8547 | ||
b0a873eb | 8548 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8549 | { |
76e1d904 FW |
8550 | int err; |
8551 | ||
b0a873eb PZ |
8552 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8553 | return -ENOENT; | |
8554 | ||
2481c5fa SE |
8555 | /* |
8556 | * no branch sampling for tracepoint events | |
8557 | */ | |
8558 | if (has_branch_stack(event)) | |
8559 | return -EOPNOTSUPP; | |
8560 | ||
1c024eca PZ |
8561 | err = perf_trace_init(event); |
8562 | if (err) | |
b0a873eb | 8563 | return err; |
e077df4f | 8564 | |
cdd6c482 | 8565 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8566 | |
b0a873eb PZ |
8567 | return 0; |
8568 | } | |
8569 | ||
8570 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8571 | .task_ctx_nr = perf_sw_context, |
8572 | ||
b0a873eb | 8573 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8574 | .add = perf_trace_add, |
8575 | .del = perf_trace_del, | |
8576 | .start = perf_swevent_start, | |
8577 | .stop = perf_swevent_stop, | |
b0a873eb | 8578 | .read = perf_swevent_read, |
b0a873eb PZ |
8579 | }; |
8580 | ||
33ea4b24 | 8581 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
8582 | /* |
8583 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
8584 | * The flags should match following PMU_FORMAT_ATTR(). | |
8585 | * | |
8586 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
8587 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
8588 | * |
8589 | * The following values specify a reference counter (or semaphore in the | |
8590 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
8591 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
8592 | * | |
8593 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
8594 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
8595 | */ |
8596 | enum perf_probe_config { | |
8597 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
8598 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
8599 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
8600 | }; |
8601 | ||
8602 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 8603 | #endif |
e12f03d7 | 8604 | |
a6ca88b2 SL |
8605 | #ifdef CONFIG_KPROBE_EVENTS |
8606 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
8607 | &format_attr_retprobe.attr, |
8608 | NULL, | |
8609 | }; | |
8610 | ||
a6ca88b2 | 8611 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 8612 | .name = "format", |
a6ca88b2 | 8613 | .attrs = kprobe_attrs, |
e12f03d7 SL |
8614 | }; |
8615 | ||
a6ca88b2 SL |
8616 | static const struct attribute_group *kprobe_attr_groups[] = { |
8617 | &kprobe_format_group, | |
e12f03d7 SL |
8618 | NULL, |
8619 | }; | |
8620 | ||
8621 | static int perf_kprobe_event_init(struct perf_event *event); | |
8622 | static struct pmu perf_kprobe = { | |
8623 | .task_ctx_nr = perf_sw_context, | |
8624 | .event_init = perf_kprobe_event_init, | |
8625 | .add = perf_trace_add, | |
8626 | .del = perf_trace_del, | |
8627 | .start = perf_swevent_start, | |
8628 | .stop = perf_swevent_stop, | |
8629 | .read = perf_swevent_read, | |
a6ca88b2 | 8630 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
8631 | }; |
8632 | ||
8633 | static int perf_kprobe_event_init(struct perf_event *event) | |
8634 | { | |
8635 | int err; | |
8636 | bool is_retprobe; | |
8637 | ||
8638 | if (event->attr.type != perf_kprobe.type) | |
8639 | return -ENOENT; | |
32e6e967 SL |
8640 | |
8641 | if (!capable(CAP_SYS_ADMIN)) | |
8642 | return -EACCES; | |
8643 | ||
e12f03d7 SL |
8644 | /* |
8645 | * no branch sampling for probe events | |
8646 | */ | |
8647 | if (has_branch_stack(event)) | |
8648 | return -EOPNOTSUPP; | |
8649 | ||
8650 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8651 | err = perf_kprobe_init(event, is_retprobe); | |
8652 | if (err) | |
8653 | return err; | |
8654 | ||
8655 | event->destroy = perf_kprobe_destroy; | |
8656 | ||
8657 | return 0; | |
8658 | } | |
8659 | #endif /* CONFIG_KPROBE_EVENTS */ | |
8660 | ||
33ea4b24 | 8661 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
8662 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
8663 | ||
8664 | static struct attribute *uprobe_attrs[] = { | |
8665 | &format_attr_retprobe.attr, | |
8666 | &format_attr_ref_ctr_offset.attr, | |
8667 | NULL, | |
8668 | }; | |
8669 | ||
8670 | static struct attribute_group uprobe_format_group = { | |
8671 | .name = "format", | |
8672 | .attrs = uprobe_attrs, | |
8673 | }; | |
8674 | ||
8675 | static const struct attribute_group *uprobe_attr_groups[] = { | |
8676 | &uprobe_format_group, | |
8677 | NULL, | |
8678 | }; | |
8679 | ||
33ea4b24 SL |
8680 | static int perf_uprobe_event_init(struct perf_event *event); |
8681 | static struct pmu perf_uprobe = { | |
8682 | .task_ctx_nr = perf_sw_context, | |
8683 | .event_init = perf_uprobe_event_init, | |
8684 | .add = perf_trace_add, | |
8685 | .del = perf_trace_del, | |
8686 | .start = perf_swevent_start, | |
8687 | .stop = perf_swevent_stop, | |
8688 | .read = perf_swevent_read, | |
a6ca88b2 | 8689 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
8690 | }; |
8691 | ||
8692 | static int perf_uprobe_event_init(struct perf_event *event) | |
8693 | { | |
8694 | int err; | |
a6ca88b2 | 8695 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
8696 | bool is_retprobe; |
8697 | ||
8698 | if (event->attr.type != perf_uprobe.type) | |
8699 | return -ENOENT; | |
32e6e967 SL |
8700 | |
8701 | if (!capable(CAP_SYS_ADMIN)) | |
8702 | return -EACCES; | |
8703 | ||
33ea4b24 SL |
8704 | /* |
8705 | * no branch sampling for probe events | |
8706 | */ | |
8707 | if (has_branch_stack(event)) | |
8708 | return -EOPNOTSUPP; | |
8709 | ||
8710 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
8711 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
8712 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
8713 | if (err) |
8714 | return err; | |
8715 | ||
8716 | event->destroy = perf_uprobe_destroy; | |
8717 | ||
8718 | return 0; | |
8719 | } | |
8720 | #endif /* CONFIG_UPROBE_EVENTS */ | |
8721 | ||
b0a873eb PZ |
8722 | static inline void perf_tp_register(void) |
8723 | { | |
2e80a82a | 8724 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
8725 | #ifdef CONFIG_KPROBE_EVENTS |
8726 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
8727 | #endif | |
33ea4b24 SL |
8728 | #ifdef CONFIG_UPROBE_EVENTS |
8729 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
8730 | #endif | |
e077df4f | 8731 | } |
6fb2915d | 8732 | |
6fb2915d LZ |
8733 | static void perf_event_free_filter(struct perf_event *event) |
8734 | { | |
8735 | ftrace_profile_free_filter(event); | |
8736 | } | |
8737 | ||
aa6a5f3c AS |
8738 | #ifdef CONFIG_BPF_SYSCALL |
8739 | static void bpf_overflow_handler(struct perf_event *event, | |
8740 | struct perf_sample_data *data, | |
8741 | struct pt_regs *regs) | |
8742 | { | |
8743 | struct bpf_perf_event_data_kern ctx = { | |
8744 | .data = data, | |
7d9285e8 | 8745 | .event = event, |
aa6a5f3c AS |
8746 | }; |
8747 | int ret = 0; | |
8748 | ||
c895f6f7 | 8749 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
8750 | preempt_disable(); |
8751 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
8752 | goto out; | |
8753 | rcu_read_lock(); | |
88575199 | 8754 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
8755 | rcu_read_unlock(); |
8756 | out: | |
8757 | __this_cpu_dec(bpf_prog_active); | |
8758 | preempt_enable(); | |
8759 | if (!ret) | |
8760 | return; | |
8761 | ||
8762 | event->orig_overflow_handler(event, data, regs); | |
8763 | } | |
8764 | ||
8765 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8766 | { | |
8767 | struct bpf_prog *prog; | |
8768 | ||
8769 | if (event->overflow_handler_context) | |
8770 | /* hw breakpoint or kernel counter */ | |
8771 | return -EINVAL; | |
8772 | ||
8773 | if (event->prog) | |
8774 | return -EEXIST; | |
8775 | ||
8776 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8777 | if (IS_ERR(prog)) | |
8778 | return PTR_ERR(prog); | |
8779 | ||
8780 | event->prog = prog; | |
8781 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8782 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8783 | return 0; | |
8784 | } | |
8785 | ||
8786 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8787 | { | |
8788 | struct bpf_prog *prog = event->prog; | |
8789 | ||
8790 | if (!prog) | |
8791 | return; | |
8792 | ||
8793 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
8794 | event->prog = NULL; | |
8795 | bpf_prog_put(prog); | |
8796 | } | |
8797 | #else | |
8798 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8799 | { | |
8800 | return -EOPNOTSUPP; | |
8801 | } | |
8802 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8803 | { | |
8804 | } | |
8805 | #endif | |
8806 | ||
e12f03d7 SL |
8807 | /* |
8808 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
8809 | * with perf_event_open() | |
8810 | */ | |
8811 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
8812 | { | |
8813 | if (event->pmu == &perf_tracepoint) | |
8814 | return true; | |
8815 | #ifdef CONFIG_KPROBE_EVENTS | |
8816 | if (event->pmu == &perf_kprobe) | |
8817 | return true; | |
33ea4b24 SL |
8818 | #endif |
8819 | #ifdef CONFIG_UPROBE_EVENTS | |
8820 | if (event->pmu == &perf_uprobe) | |
8821 | return true; | |
e12f03d7 SL |
8822 | #endif |
8823 | return false; | |
8824 | } | |
8825 | ||
2541517c AS |
8826 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8827 | { | |
cf5f5cea | 8828 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 8829 | struct bpf_prog *prog; |
e87c6bc3 | 8830 | int ret; |
2541517c | 8831 | |
e12f03d7 | 8832 | if (!perf_event_is_tracing(event)) |
f91840a3 | 8833 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 8834 | |
98b5c2c6 AS |
8835 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
8836 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
8837 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
8838 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 8839 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
8840 | return -EINVAL; |
8841 | ||
8842 | prog = bpf_prog_get(prog_fd); | |
8843 | if (IS_ERR(prog)) | |
8844 | return PTR_ERR(prog); | |
8845 | ||
98b5c2c6 | 8846 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
8847 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
8848 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
8849 | /* valid fd, but invalid bpf program type */ |
8850 | bpf_prog_put(prog); | |
8851 | return -EINVAL; | |
8852 | } | |
8853 | ||
9802d865 JB |
8854 | /* Kprobe override only works for kprobes, not uprobes. */ |
8855 | if (prog->kprobe_override && | |
8856 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
8857 | bpf_prog_put(prog); | |
8858 | return -EINVAL; | |
8859 | } | |
8860 | ||
cf5f5cea | 8861 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
8862 | int off = trace_event_get_offsets(event->tp_event); |
8863 | ||
8864 | if (prog->aux->max_ctx_offset > off) { | |
8865 | bpf_prog_put(prog); | |
8866 | return -EACCES; | |
8867 | } | |
8868 | } | |
2541517c | 8869 | |
e87c6bc3 YS |
8870 | ret = perf_event_attach_bpf_prog(event, prog); |
8871 | if (ret) | |
8872 | bpf_prog_put(prog); | |
8873 | return ret; | |
2541517c AS |
8874 | } |
8875 | ||
8876 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8877 | { | |
e12f03d7 | 8878 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 8879 | perf_event_free_bpf_handler(event); |
2541517c | 8880 | return; |
2541517c | 8881 | } |
e87c6bc3 | 8882 | perf_event_detach_bpf_prog(event); |
2541517c AS |
8883 | } |
8884 | ||
e077df4f | 8885 | #else |
6fb2915d | 8886 | |
b0a873eb | 8887 | static inline void perf_tp_register(void) |
e077df4f | 8888 | { |
e077df4f | 8889 | } |
6fb2915d | 8890 | |
6fb2915d LZ |
8891 | static void perf_event_free_filter(struct perf_event *event) |
8892 | { | |
8893 | } | |
8894 | ||
2541517c AS |
8895 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8896 | { | |
8897 | return -ENOENT; | |
8898 | } | |
8899 | ||
8900 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8901 | { | |
8902 | } | |
07b139c8 | 8903 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 8904 | |
24f1e32c | 8905 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 8906 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 8907 | { |
f5ffe02e FW |
8908 | struct perf_sample_data sample; |
8909 | struct pt_regs *regs = data; | |
8910 | ||
fd0d000b | 8911 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 8912 | |
a4eaf7f1 | 8913 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 8914 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
8915 | } |
8916 | #endif | |
8917 | ||
375637bc AS |
8918 | /* |
8919 | * Allocate a new address filter | |
8920 | */ | |
8921 | static struct perf_addr_filter * | |
8922 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
8923 | { | |
8924 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
8925 | struct perf_addr_filter *filter; | |
8926 | ||
8927 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
8928 | if (!filter) | |
8929 | return NULL; | |
8930 | ||
8931 | INIT_LIST_HEAD(&filter->entry); | |
8932 | list_add_tail(&filter->entry, filters); | |
8933 | ||
8934 | return filter; | |
8935 | } | |
8936 | ||
8937 | static void free_filters_list(struct list_head *filters) | |
8938 | { | |
8939 | struct perf_addr_filter *filter, *iter; | |
8940 | ||
8941 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 8942 | path_put(&filter->path); |
375637bc AS |
8943 | list_del(&filter->entry); |
8944 | kfree(filter); | |
8945 | } | |
8946 | } | |
8947 | ||
8948 | /* | |
8949 | * Free existing address filters and optionally install new ones | |
8950 | */ | |
8951 | static void perf_addr_filters_splice(struct perf_event *event, | |
8952 | struct list_head *head) | |
8953 | { | |
8954 | unsigned long flags; | |
8955 | LIST_HEAD(list); | |
8956 | ||
8957 | if (!has_addr_filter(event)) | |
8958 | return; | |
8959 | ||
8960 | /* don't bother with children, they don't have their own filters */ | |
8961 | if (event->parent) | |
8962 | return; | |
8963 | ||
8964 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
8965 | ||
8966 | list_splice_init(&event->addr_filters.list, &list); | |
8967 | if (head) | |
8968 | list_splice(head, &event->addr_filters.list); | |
8969 | ||
8970 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
8971 | ||
8972 | free_filters_list(&list); | |
8973 | } | |
8974 | ||
8975 | /* | |
8976 | * Scan through mm's vmas and see if one of them matches the | |
8977 | * @filter; if so, adjust filter's address range. | |
8978 | * Called with mm::mmap_sem down for reading. | |
8979 | */ | |
8980 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8981 | struct mm_struct *mm) | |
8982 | { | |
8983 | struct vm_area_struct *vma; | |
8984 | ||
8985 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8986 | struct file *file = vma->vm_file; | |
8987 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8988 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8989 | ||
8990 | if (!file) | |
8991 | continue; | |
8992 | ||
8993 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8994 | continue; | |
8995 | ||
8996 | return vma->vm_start; | |
8997 | } | |
8998 | ||
8999 | return 0; | |
9000 | } | |
9001 | ||
9002 | /* | |
9003 | * Update event's address range filters based on the | |
9004 | * task's existing mappings, if any. | |
9005 | */ | |
9006 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9007 | { | |
9008 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9009 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9010 | struct perf_addr_filter *filter; | |
9011 | struct mm_struct *mm = NULL; | |
9012 | unsigned int count = 0; | |
9013 | unsigned long flags; | |
9014 | ||
9015 | /* | |
9016 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9017 | * will stop on the parent's child_mutex that our caller is also holding | |
9018 | */ | |
9019 | if (task == TASK_TOMBSTONE) | |
9020 | return; | |
9021 | ||
6ce77bfd AS |
9022 | if (!ifh->nr_file_filters) |
9023 | return; | |
9024 | ||
375637bc AS |
9025 | mm = get_task_mm(event->ctx->task); |
9026 | if (!mm) | |
9027 | goto restart; | |
9028 | ||
9029 | down_read(&mm->mmap_sem); | |
9030 | ||
9031 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9032 | list_for_each_entry(filter, &ifh->list, entry) { | |
9033 | event->addr_filters_offs[count] = 0; | |
9034 | ||
99f5bc9b MP |
9035 | /* |
9036 | * Adjust base offset if the filter is associated to a binary | |
9037 | * that needs to be mapped: | |
9038 | */ | |
9511bce9 | 9039 | if (filter->path.dentry) |
375637bc AS |
9040 | event->addr_filters_offs[count] = |
9041 | perf_addr_filter_apply(filter, mm); | |
9042 | ||
9043 | count++; | |
9044 | } | |
9045 | ||
9046 | event->addr_filters_gen++; | |
9047 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9048 | ||
9049 | up_read(&mm->mmap_sem); | |
9050 | ||
9051 | mmput(mm); | |
9052 | ||
9053 | restart: | |
767ae086 | 9054 | perf_event_stop(event, 1); |
375637bc AS |
9055 | } |
9056 | ||
9057 | /* | |
9058 | * Address range filtering: limiting the data to certain | |
9059 | * instruction address ranges. Filters are ioctl()ed to us from | |
9060 | * userspace as ascii strings. | |
9061 | * | |
9062 | * Filter string format: | |
9063 | * | |
9064 | * ACTION RANGE_SPEC | |
9065 | * where ACTION is one of the | |
9066 | * * "filter": limit the trace to this region | |
9067 | * * "start": start tracing from this address | |
9068 | * * "stop": stop tracing at this address/region; | |
9069 | * RANGE_SPEC is | |
9070 | * * for kernel addresses: <start address>[/<size>] | |
9071 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9072 | * | |
6ed70cf3 AS |
9073 | * if <size> is not specified or is zero, the range is treated as a single |
9074 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9075 | */ |
9076 | enum { | |
e96271f3 | 9077 | IF_ACT_NONE = -1, |
375637bc AS |
9078 | IF_ACT_FILTER, |
9079 | IF_ACT_START, | |
9080 | IF_ACT_STOP, | |
9081 | IF_SRC_FILE, | |
9082 | IF_SRC_KERNEL, | |
9083 | IF_SRC_FILEADDR, | |
9084 | IF_SRC_KERNELADDR, | |
9085 | }; | |
9086 | ||
9087 | enum { | |
9088 | IF_STATE_ACTION = 0, | |
9089 | IF_STATE_SOURCE, | |
9090 | IF_STATE_END, | |
9091 | }; | |
9092 | ||
9093 | static const match_table_t if_tokens = { | |
9094 | { IF_ACT_FILTER, "filter" }, | |
9095 | { IF_ACT_START, "start" }, | |
9096 | { IF_ACT_STOP, "stop" }, | |
9097 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9098 | { IF_SRC_KERNEL, "%u/%u" }, | |
9099 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9100 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9101 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9102 | }; |
9103 | ||
9104 | /* | |
9105 | * Address filter string parser | |
9106 | */ | |
9107 | static int | |
9108 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9109 | struct list_head *filters) | |
9110 | { | |
9111 | struct perf_addr_filter *filter = NULL; | |
9112 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9113 | substring_t args[MAX_OPT_ARGS]; |
9114 | int state = IF_STATE_ACTION, token; | |
9115 | unsigned int kernel = 0; | |
9116 | int ret = -EINVAL; | |
9117 | ||
9118 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9119 | if (!fstr) | |
9120 | return -ENOMEM; | |
9121 | ||
9122 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9123 | static const enum perf_addr_filter_action_t actions[] = { |
9124 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9125 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9126 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9127 | }; | |
375637bc AS |
9128 | ret = -EINVAL; |
9129 | ||
9130 | if (!*start) | |
9131 | continue; | |
9132 | ||
9133 | /* filter definition begins */ | |
9134 | if (state == IF_STATE_ACTION) { | |
9135 | filter = perf_addr_filter_new(event, filters); | |
9136 | if (!filter) | |
9137 | goto fail; | |
9138 | } | |
9139 | ||
9140 | token = match_token(start, if_tokens, args); | |
9141 | switch (token) { | |
9142 | case IF_ACT_FILTER: | |
9143 | case IF_ACT_START: | |
375637bc AS |
9144 | case IF_ACT_STOP: |
9145 | if (state != IF_STATE_ACTION) | |
9146 | goto fail; | |
9147 | ||
6ed70cf3 | 9148 | filter->action = actions[token]; |
375637bc AS |
9149 | state = IF_STATE_SOURCE; |
9150 | break; | |
9151 | ||
9152 | case IF_SRC_KERNELADDR: | |
9153 | case IF_SRC_KERNEL: | |
9154 | kernel = 1; | |
9155 | ||
9156 | case IF_SRC_FILEADDR: | |
9157 | case IF_SRC_FILE: | |
9158 | if (state != IF_STATE_SOURCE) | |
9159 | goto fail; | |
9160 | ||
375637bc AS |
9161 | *args[0].to = 0; |
9162 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9163 | if (ret) | |
9164 | goto fail; | |
9165 | ||
6ed70cf3 | 9166 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9167 | *args[1].to = 0; |
9168 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9169 | if (ret) | |
9170 | goto fail; | |
9171 | } | |
9172 | ||
4059ffd0 | 9173 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9174 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9175 | |
9176 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9177 | if (!filename) { |
9178 | ret = -ENOMEM; | |
9179 | goto fail; | |
9180 | } | |
9181 | } | |
9182 | ||
9183 | state = IF_STATE_END; | |
9184 | break; | |
9185 | ||
9186 | default: | |
9187 | goto fail; | |
9188 | } | |
9189 | ||
9190 | /* | |
9191 | * Filter definition is fully parsed, validate and install it. | |
9192 | * Make sure that it doesn't contradict itself or the event's | |
9193 | * attribute. | |
9194 | */ | |
9195 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9196 | ret = -EINVAL; |
375637bc AS |
9197 | if (kernel && event->attr.exclude_kernel) |
9198 | goto fail; | |
9199 | ||
6ed70cf3 AS |
9200 | /* |
9201 | * ACTION "filter" must have a non-zero length region | |
9202 | * specified. | |
9203 | */ | |
9204 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9205 | !filter->size) | |
9206 | goto fail; | |
9207 | ||
375637bc AS |
9208 | if (!kernel) { |
9209 | if (!filename) | |
9210 | goto fail; | |
9211 | ||
6ce77bfd AS |
9212 | /* |
9213 | * For now, we only support file-based filters | |
9214 | * in per-task events; doing so for CPU-wide | |
9215 | * events requires additional context switching | |
9216 | * trickery, since same object code will be | |
9217 | * mapped at different virtual addresses in | |
9218 | * different processes. | |
9219 | */ | |
9220 | ret = -EOPNOTSUPP; | |
9221 | if (!event->ctx->task) | |
9222 | goto fail_free_name; | |
9223 | ||
375637bc | 9224 | /* look up the path and grab its inode */ |
9511bce9 SL |
9225 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9226 | &filter->path); | |
375637bc AS |
9227 | if (ret) |
9228 | goto fail_free_name; | |
9229 | ||
375637bc AS |
9230 | kfree(filename); |
9231 | filename = NULL; | |
9232 | ||
9233 | ret = -EINVAL; | |
9511bce9 SL |
9234 | if (!filter->path.dentry || |
9235 | !S_ISREG(d_inode(filter->path.dentry) | |
9236 | ->i_mode)) | |
375637bc | 9237 | goto fail; |
6ce77bfd AS |
9238 | |
9239 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9240 | } |
9241 | ||
9242 | /* ready to consume more filters */ | |
9243 | state = IF_STATE_ACTION; | |
9244 | filter = NULL; | |
9245 | } | |
9246 | } | |
9247 | ||
9248 | if (state != IF_STATE_ACTION) | |
9249 | goto fail; | |
9250 | ||
9251 | kfree(orig); | |
9252 | ||
9253 | return 0; | |
9254 | ||
9255 | fail_free_name: | |
9256 | kfree(filename); | |
9257 | fail: | |
9258 | free_filters_list(filters); | |
9259 | kfree(orig); | |
9260 | ||
9261 | return ret; | |
9262 | } | |
9263 | ||
9264 | static int | |
9265 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9266 | { | |
9267 | LIST_HEAD(filters); | |
9268 | int ret; | |
9269 | ||
9270 | /* | |
9271 | * Since this is called in perf_ioctl() path, we're already holding | |
9272 | * ctx::mutex. | |
9273 | */ | |
9274 | lockdep_assert_held(&event->ctx->mutex); | |
9275 | ||
9276 | if (WARN_ON_ONCE(event->parent)) | |
9277 | return -EINVAL; | |
9278 | ||
375637bc AS |
9279 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9280 | if (ret) | |
6ce77bfd | 9281 | goto fail_clear_files; |
375637bc AS |
9282 | |
9283 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9284 | if (ret) |
9285 | goto fail_free_filters; | |
375637bc AS |
9286 | |
9287 | /* remove existing filters, if any */ | |
9288 | perf_addr_filters_splice(event, &filters); | |
9289 | ||
9290 | /* install new filters */ | |
9291 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9292 | ||
6ce77bfd AS |
9293 | return ret; |
9294 | ||
9295 | fail_free_filters: | |
9296 | free_filters_list(&filters); | |
9297 | ||
9298 | fail_clear_files: | |
9299 | event->addr_filters.nr_file_filters = 0; | |
9300 | ||
375637bc AS |
9301 | return ret; |
9302 | } | |
9303 | ||
c796bbbe AS |
9304 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9305 | { | |
c796bbbe | 9306 | int ret = -EINVAL; |
e12f03d7 | 9307 | char *filter_str; |
c796bbbe AS |
9308 | |
9309 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9310 | if (IS_ERR(filter_str)) | |
9311 | return PTR_ERR(filter_str); | |
9312 | ||
e12f03d7 SL |
9313 | #ifdef CONFIG_EVENT_TRACING |
9314 | if (perf_event_is_tracing(event)) { | |
9315 | struct perf_event_context *ctx = event->ctx; | |
9316 | ||
9317 | /* | |
9318 | * Beware, here be dragons!! | |
9319 | * | |
9320 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9321 | * the tracepoint stuff does not actually need it. So | |
9322 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9323 | * already have a reference on ctx. | |
9324 | * | |
9325 | * This can result in event getting moved to a different ctx, | |
9326 | * but that does not affect the tracepoint state. | |
9327 | */ | |
9328 | mutex_unlock(&ctx->mutex); | |
9329 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9330 | mutex_lock(&ctx->mutex); | |
9331 | } else | |
9332 | #endif | |
9333 | if (has_addr_filter(event)) | |
375637bc | 9334 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9335 | |
9336 | kfree(filter_str); | |
9337 | return ret; | |
9338 | } | |
9339 | ||
b0a873eb PZ |
9340 | /* |
9341 | * hrtimer based swevent callback | |
9342 | */ | |
f29ac756 | 9343 | |
b0a873eb | 9344 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9345 | { |
b0a873eb PZ |
9346 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9347 | struct perf_sample_data data; | |
9348 | struct pt_regs *regs; | |
9349 | struct perf_event *event; | |
9350 | u64 period; | |
f29ac756 | 9351 | |
b0a873eb | 9352 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9353 | |
9354 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9355 | return HRTIMER_NORESTART; | |
9356 | ||
b0a873eb | 9357 | event->pmu->read(event); |
f344011c | 9358 | |
fd0d000b | 9359 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9360 | regs = get_irq_regs(); |
9361 | ||
9362 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9363 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9364 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9365 | ret = HRTIMER_NORESTART; |
9366 | } | |
24f1e32c | 9367 | |
b0a873eb PZ |
9368 | period = max_t(u64, 10000, event->hw.sample_period); |
9369 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9370 | |
b0a873eb | 9371 | return ret; |
f29ac756 PZ |
9372 | } |
9373 | ||
b0a873eb | 9374 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9375 | { |
b0a873eb | 9376 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9377 | s64 period; |
9378 | ||
9379 | if (!is_sampling_event(event)) | |
9380 | return; | |
f5ffe02e | 9381 | |
5d508e82 FBH |
9382 | period = local64_read(&hwc->period_left); |
9383 | if (period) { | |
9384 | if (period < 0) | |
9385 | period = 10000; | |
fa407f35 | 9386 | |
5d508e82 FBH |
9387 | local64_set(&hwc->period_left, 0); |
9388 | } else { | |
9389 | period = max_t(u64, 10000, hwc->sample_period); | |
9390 | } | |
3497d206 TG |
9391 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
9392 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 9393 | } |
b0a873eb PZ |
9394 | |
9395 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9396 | { |
b0a873eb PZ |
9397 | struct hw_perf_event *hwc = &event->hw; |
9398 | ||
6c7e550f | 9399 | if (is_sampling_event(event)) { |
b0a873eb | 9400 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9401 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9402 | |
9403 | hrtimer_cancel(&hwc->hrtimer); | |
9404 | } | |
24f1e32c FW |
9405 | } |
9406 | ||
ba3dd36c PZ |
9407 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9408 | { | |
9409 | struct hw_perf_event *hwc = &event->hw; | |
9410 | ||
9411 | if (!is_sampling_event(event)) | |
9412 | return; | |
9413 | ||
9414 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
9415 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
9416 | ||
9417 | /* | |
9418 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9419 | * mapping and avoid the whole period adjust feedback stuff. | |
9420 | */ | |
9421 | if (event->attr.freq) { | |
9422 | long freq = event->attr.sample_freq; | |
9423 | ||
9424 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9425 | hwc->sample_period = event->attr.sample_period; | |
9426 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9427 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9428 | event->attr.freq = 0; |
9429 | } | |
9430 | } | |
9431 | ||
b0a873eb PZ |
9432 | /* |
9433 | * Software event: cpu wall time clock | |
9434 | */ | |
9435 | ||
9436 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9437 | { |
b0a873eb PZ |
9438 | s64 prev; |
9439 | u64 now; | |
9440 | ||
a4eaf7f1 | 9441 | now = local_clock(); |
b0a873eb PZ |
9442 | prev = local64_xchg(&event->hw.prev_count, now); |
9443 | local64_add(now - prev, &event->count); | |
24f1e32c | 9444 | } |
24f1e32c | 9445 | |
a4eaf7f1 | 9446 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9447 | { |
a4eaf7f1 | 9448 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9449 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9450 | } |
9451 | ||
a4eaf7f1 | 9452 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9453 | { |
b0a873eb PZ |
9454 | perf_swevent_cancel_hrtimer(event); |
9455 | cpu_clock_event_update(event); | |
9456 | } | |
f29ac756 | 9457 | |
a4eaf7f1 PZ |
9458 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9459 | { | |
9460 | if (flags & PERF_EF_START) | |
9461 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9462 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9463 | |
9464 | return 0; | |
9465 | } | |
9466 | ||
9467 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9468 | { | |
9469 | cpu_clock_event_stop(event, flags); | |
9470 | } | |
9471 | ||
b0a873eb PZ |
9472 | static void cpu_clock_event_read(struct perf_event *event) |
9473 | { | |
9474 | cpu_clock_event_update(event); | |
9475 | } | |
f344011c | 9476 | |
b0a873eb PZ |
9477 | static int cpu_clock_event_init(struct perf_event *event) |
9478 | { | |
9479 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9480 | return -ENOENT; | |
9481 | ||
9482 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9483 | return -ENOENT; | |
9484 | ||
2481c5fa SE |
9485 | /* |
9486 | * no branch sampling for software events | |
9487 | */ | |
9488 | if (has_branch_stack(event)) | |
9489 | return -EOPNOTSUPP; | |
9490 | ||
ba3dd36c PZ |
9491 | perf_swevent_init_hrtimer(event); |
9492 | ||
b0a873eb | 9493 | return 0; |
f29ac756 PZ |
9494 | } |
9495 | ||
b0a873eb | 9496 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9497 | .task_ctx_nr = perf_sw_context, |
9498 | ||
34f43927 PZ |
9499 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9500 | ||
b0a873eb | 9501 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9502 | .add = cpu_clock_event_add, |
9503 | .del = cpu_clock_event_del, | |
9504 | .start = cpu_clock_event_start, | |
9505 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9506 | .read = cpu_clock_event_read, |
9507 | }; | |
9508 | ||
9509 | /* | |
9510 | * Software event: task time clock | |
9511 | */ | |
9512 | ||
9513 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9514 | { |
b0a873eb PZ |
9515 | u64 prev; |
9516 | s64 delta; | |
5c92d124 | 9517 | |
b0a873eb PZ |
9518 | prev = local64_xchg(&event->hw.prev_count, now); |
9519 | delta = now - prev; | |
9520 | local64_add(delta, &event->count); | |
9521 | } | |
5c92d124 | 9522 | |
a4eaf7f1 | 9523 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9524 | { |
a4eaf7f1 | 9525 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9526 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9527 | } |
9528 | ||
a4eaf7f1 | 9529 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9530 | { |
9531 | perf_swevent_cancel_hrtimer(event); | |
9532 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9533 | } |
9534 | ||
9535 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9536 | { | |
9537 | if (flags & PERF_EF_START) | |
9538 | task_clock_event_start(event, flags); | |
6a694a60 | 9539 | perf_event_update_userpage(event); |
b0a873eb | 9540 | |
a4eaf7f1 PZ |
9541 | return 0; |
9542 | } | |
9543 | ||
9544 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9545 | { | |
9546 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9547 | } |
9548 | ||
9549 | static void task_clock_event_read(struct perf_event *event) | |
9550 | { | |
768a06e2 PZ |
9551 | u64 now = perf_clock(); |
9552 | u64 delta = now - event->ctx->timestamp; | |
9553 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
9554 | |
9555 | task_clock_event_update(event, time); | |
9556 | } | |
9557 | ||
9558 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 9559 | { |
b0a873eb PZ |
9560 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
9561 | return -ENOENT; | |
9562 | ||
9563 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
9564 | return -ENOENT; | |
9565 | ||
2481c5fa SE |
9566 | /* |
9567 | * no branch sampling for software events | |
9568 | */ | |
9569 | if (has_branch_stack(event)) | |
9570 | return -EOPNOTSUPP; | |
9571 | ||
ba3dd36c PZ |
9572 | perf_swevent_init_hrtimer(event); |
9573 | ||
b0a873eb | 9574 | return 0; |
6fb2915d LZ |
9575 | } |
9576 | ||
b0a873eb | 9577 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
9578 | .task_ctx_nr = perf_sw_context, |
9579 | ||
34f43927 PZ |
9580 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9581 | ||
b0a873eb | 9582 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
9583 | .add = task_clock_event_add, |
9584 | .del = task_clock_event_del, | |
9585 | .start = task_clock_event_start, | |
9586 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
9587 | .read = task_clock_event_read, |
9588 | }; | |
6fb2915d | 9589 | |
ad5133b7 | 9590 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 9591 | { |
e077df4f | 9592 | } |
6fb2915d | 9593 | |
fbbe0701 SB |
9594 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
9595 | { | |
9596 | } | |
9597 | ||
ad5133b7 | 9598 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 9599 | { |
ad5133b7 | 9600 | return 0; |
6fb2915d LZ |
9601 | } |
9602 | ||
18ab2cd3 | 9603 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
9604 | |
9605 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 9606 | { |
fbbe0701 SB |
9607 | __this_cpu_write(nop_txn_flags, flags); |
9608 | ||
9609 | if (flags & ~PERF_PMU_TXN_ADD) | |
9610 | return; | |
9611 | ||
ad5133b7 | 9612 | perf_pmu_disable(pmu); |
6fb2915d LZ |
9613 | } |
9614 | ||
ad5133b7 PZ |
9615 | static int perf_pmu_commit_txn(struct pmu *pmu) |
9616 | { | |
fbbe0701 SB |
9617 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9618 | ||
9619 | __this_cpu_write(nop_txn_flags, 0); | |
9620 | ||
9621 | if (flags & ~PERF_PMU_TXN_ADD) | |
9622 | return 0; | |
9623 | ||
ad5133b7 PZ |
9624 | perf_pmu_enable(pmu); |
9625 | return 0; | |
9626 | } | |
e077df4f | 9627 | |
ad5133b7 | 9628 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 9629 | { |
fbbe0701 SB |
9630 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9631 | ||
9632 | __this_cpu_write(nop_txn_flags, 0); | |
9633 | ||
9634 | if (flags & ~PERF_PMU_TXN_ADD) | |
9635 | return; | |
9636 | ||
ad5133b7 | 9637 | perf_pmu_enable(pmu); |
24f1e32c FW |
9638 | } |
9639 | ||
35edc2a5 PZ |
9640 | static int perf_event_idx_default(struct perf_event *event) |
9641 | { | |
c719f560 | 9642 | return 0; |
35edc2a5 PZ |
9643 | } |
9644 | ||
8dc85d54 PZ |
9645 | /* |
9646 | * Ensures all contexts with the same task_ctx_nr have the same | |
9647 | * pmu_cpu_context too. | |
9648 | */ | |
9e317041 | 9649 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 9650 | { |
8dc85d54 | 9651 | struct pmu *pmu; |
b326e956 | 9652 | |
8dc85d54 PZ |
9653 | if (ctxn < 0) |
9654 | return NULL; | |
24f1e32c | 9655 | |
8dc85d54 PZ |
9656 | list_for_each_entry(pmu, &pmus, entry) { |
9657 | if (pmu->task_ctx_nr == ctxn) | |
9658 | return pmu->pmu_cpu_context; | |
9659 | } | |
24f1e32c | 9660 | |
8dc85d54 | 9661 | return NULL; |
24f1e32c FW |
9662 | } |
9663 | ||
51676957 PZ |
9664 | static void free_pmu_context(struct pmu *pmu) |
9665 | { | |
df0062b2 WD |
9666 | /* |
9667 | * Static contexts such as perf_sw_context have a global lifetime | |
9668 | * and may be shared between different PMUs. Avoid freeing them | |
9669 | * when a single PMU is going away. | |
9670 | */ | |
9671 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9672 | return; | |
9673 | ||
51676957 | 9674 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 9675 | } |
6e855cd4 AS |
9676 | |
9677 | /* | |
9678 | * Let userspace know that this PMU supports address range filtering: | |
9679 | */ | |
9680 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9681 | struct device_attribute *attr, | |
9682 | char *page) | |
9683 | { | |
9684 | struct pmu *pmu = dev_get_drvdata(dev); | |
9685 | ||
9686 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9687 | } | |
9688 | DEVICE_ATTR_RO(nr_addr_filters); | |
9689 | ||
2e80a82a | 9690 | static struct idr pmu_idr; |
d6d020e9 | 9691 | |
abe43400 PZ |
9692 | static ssize_t |
9693 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9694 | { | |
9695 | struct pmu *pmu = dev_get_drvdata(dev); | |
9696 | ||
9697 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9698 | } | |
90826ca7 | 9699 | static DEVICE_ATTR_RO(type); |
abe43400 | 9700 | |
62b85639 SE |
9701 | static ssize_t |
9702 | perf_event_mux_interval_ms_show(struct device *dev, | |
9703 | struct device_attribute *attr, | |
9704 | char *page) | |
9705 | { | |
9706 | struct pmu *pmu = dev_get_drvdata(dev); | |
9707 | ||
9708 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9709 | } | |
9710 | ||
272325c4 PZ |
9711 | static DEFINE_MUTEX(mux_interval_mutex); |
9712 | ||
62b85639 SE |
9713 | static ssize_t |
9714 | perf_event_mux_interval_ms_store(struct device *dev, | |
9715 | struct device_attribute *attr, | |
9716 | const char *buf, size_t count) | |
9717 | { | |
9718 | struct pmu *pmu = dev_get_drvdata(dev); | |
9719 | int timer, cpu, ret; | |
9720 | ||
9721 | ret = kstrtoint(buf, 0, &timer); | |
9722 | if (ret) | |
9723 | return ret; | |
9724 | ||
9725 | if (timer < 1) | |
9726 | return -EINVAL; | |
9727 | ||
9728 | /* same value, noting to do */ | |
9729 | if (timer == pmu->hrtimer_interval_ms) | |
9730 | return count; | |
9731 | ||
272325c4 | 9732 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9733 | pmu->hrtimer_interval_ms = timer; |
9734 | ||
9735 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9736 | cpus_read_lock(); |
272325c4 | 9737 | for_each_online_cpu(cpu) { |
62b85639 SE |
9738 | struct perf_cpu_context *cpuctx; |
9739 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
9740 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9741 | ||
272325c4 PZ |
9742 | cpu_function_call(cpu, |
9743 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 9744 | } |
a63fbed7 | 9745 | cpus_read_unlock(); |
272325c4 | 9746 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
9747 | |
9748 | return count; | |
9749 | } | |
90826ca7 | 9750 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 9751 | |
90826ca7 GKH |
9752 | static struct attribute *pmu_dev_attrs[] = { |
9753 | &dev_attr_type.attr, | |
9754 | &dev_attr_perf_event_mux_interval_ms.attr, | |
9755 | NULL, | |
abe43400 | 9756 | }; |
90826ca7 | 9757 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
9758 | |
9759 | static int pmu_bus_running; | |
9760 | static struct bus_type pmu_bus = { | |
9761 | .name = "event_source", | |
90826ca7 | 9762 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
9763 | }; |
9764 | ||
9765 | static void pmu_dev_release(struct device *dev) | |
9766 | { | |
9767 | kfree(dev); | |
9768 | } | |
9769 | ||
9770 | static int pmu_dev_alloc(struct pmu *pmu) | |
9771 | { | |
9772 | int ret = -ENOMEM; | |
9773 | ||
9774 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
9775 | if (!pmu->dev) | |
9776 | goto out; | |
9777 | ||
0c9d42ed | 9778 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
9779 | device_initialize(pmu->dev); |
9780 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
9781 | if (ret) | |
9782 | goto free_dev; | |
9783 | ||
9784 | dev_set_drvdata(pmu->dev, pmu); | |
9785 | pmu->dev->bus = &pmu_bus; | |
9786 | pmu->dev->release = pmu_dev_release; | |
9787 | ret = device_add(pmu->dev); | |
9788 | if (ret) | |
9789 | goto free_dev; | |
9790 | ||
6e855cd4 AS |
9791 | /* For PMUs with address filters, throw in an extra attribute: */ |
9792 | if (pmu->nr_addr_filters) | |
9793 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9794 | ||
9795 | if (ret) | |
9796 | goto del_dev; | |
9797 | ||
abe43400 PZ |
9798 | out: |
9799 | return ret; | |
9800 | ||
6e855cd4 AS |
9801 | del_dev: |
9802 | device_del(pmu->dev); | |
9803 | ||
abe43400 PZ |
9804 | free_dev: |
9805 | put_device(pmu->dev); | |
9806 | goto out; | |
9807 | } | |
9808 | ||
547e9fd7 | 9809 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 9810 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 9811 | |
03d8e80b | 9812 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 9813 | { |
108b02cf | 9814 | int cpu, ret; |
24f1e32c | 9815 | |
b0a873eb | 9816 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
9817 | ret = -ENOMEM; |
9818 | pmu->pmu_disable_count = alloc_percpu(int); | |
9819 | if (!pmu->pmu_disable_count) | |
9820 | goto unlock; | |
f29ac756 | 9821 | |
2e80a82a PZ |
9822 | pmu->type = -1; |
9823 | if (!name) | |
9824 | goto skip_type; | |
9825 | pmu->name = name; | |
9826 | ||
9827 | if (type < 0) { | |
0e9c3be2 TH |
9828 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
9829 | if (type < 0) { | |
9830 | ret = type; | |
2e80a82a PZ |
9831 | goto free_pdc; |
9832 | } | |
9833 | } | |
9834 | pmu->type = type; | |
9835 | ||
abe43400 PZ |
9836 | if (pmu_bus_running) { |
9837 | ret = pmu_dev_alloc(pmu); | |
9838 | if (ret) | |
9839 | goto free_idr; | |
9840 | } | |
9841 | ||
2e80a82a | 9842 | skip_type: |
26657848 PZ |
9843 | if (pmu->task_ctx_nr == perf_hw_context) { |
9844 | static int hw_context_taken = 0; | |
9845 | ||
5101ef20 MR |
9846 | /* |
9847 | * Other than systems with heterogeneous CPUs, it never makes | |
9848 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
9849 | * uncore must use perf_invalid_context. | |
9850 | */ | |
9851 | if (WARN_ON_ONCE(hw_context_taken && | |
9852 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
9853 | pmu->task_ctx_nr = perf_invalid_context; |
9854 | ||
9855 | hw_context_taken = 1; | |
9856 | } | |
9857 | ||
8dc85d54 PZ |
9858 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
9859 | if (pmu->pmu_cpu_context) | |
9860 | goto got_cpu_context; | |
f29ac756 | 9861 | |
c4814202 | 9862 | ret = -ENOMEM; |
108b02cf PZ |
9863 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
9864 | if (!pmu->pmu_cpu_context) | |
abe43400 | 9865 | goto free_dev; |
f344011c | 9866 | |
108b02cf PZ |
9867 | for_each_possible_cpu(cpu) { |
9868 | struct perf_cpu_context *cpuctx; | |
9869 | ||
9870 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 9871 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 9872 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 9873 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 9874 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 9875 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 9876 | |
272325c4 | 9877 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 9878 | } |
76e1d904 | 9879 | |
8dc85d54 | 9880 | got_cpu_context: |
ad5133b7 PZ |
9881 | if (!pmu->start_txn) { |
9882 | if (pmu->pmu_enable) { | |
9883 | /* | |
9884 | * If we have pmu_enable/pmu_disable calls, install | |
9885 | * transaction stubs that use that to try and batch | |
9886 | * hardware accesses. | |
9887 | */ | |
9888 | pmu->start_txn = perf_pmu_start_txn; | |
9889 | pmu->commit_txn = perf_pmu_commit_txn; | |
9890 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
9891 | } else { | |
fbbe0701 | 9892 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
9893 | pmu->commit_txn = perf_pmu_nop_int; |
9894 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 9895 | } |
5c92d124 | 9896 | } |
15dbf27c | 9897 | |
ad5133b7 PZ |
9898 | if (!pmu->pmu_enable) { |
9899 | pmu->pmu_enable = perf_pmu_nop_void; | |
9900 | pmu->pmu_disable = perf_pmu_nop_void; | |
9901 | } | |
9902 | ||
35edc2a5 PZ |
9903 | if (!pmu->event_idx) |
9904 | pmu->event_idx = perf_event_idx_default; | |
9905 | ||
b0a873eb | 9906 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 9907 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
9908 | ret = 0; |
9909 | unlock: | |
b0a873eb PZ |
9910 | mutex_unlock(&pmus_lock); |
9911 | ||
33696fc0 | 9912 | return ret; |
108b02cf | 9913 | |
abe43400 PZ |
9914 | free_dev: |
9915 | device_del(pmu->dev); | |
9916 | put_device(pmu->dev); | |
9917 | ||
2e80a82a PZ |
9918 | free_idr: |
9919 | if (pmu->type >= PERF_TYPE_MAX) | |
9920 | idr_remove(&pmu_idr, pmu->type); | |
9921 | ||
108b02cf PZ |
9922 | free_pdc: |
9923 | free_percpu(pmu->pmu_disable_count); | |
9924 | goto unlock; | |
f29ac756 | 9925 | } |
c464c76e | 9926 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 9927 | |
b0a873eb | 9928 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 9929 | { |
b0a873eb PZ |
9930 | mutex_lock(&pmus_lock); |
9931 | list_del_rcu(&pmu->entry); | |
5c92d124 | 9932 | |
0475f9ea | 9933 | /* |
cde8e884 PZ |
9934 | * We dereference the pmu list under both SRCU and regular RCU, so |
9935 | * synchronize against both of those. | |
0475f9ea | 9936 | */ |
b0a873eb | 9937 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 9938 | synchronize_rcu(); |
d6d020e9 | 9939 | |
33696fc0 | 9940 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
9941 | if (pmu->type >= PERF_TYPE_MAX) |
9942 | idr_remove(&pmu_idr, pmu->type); | |
a9f97721 | 9943 | if (pmu_bus_running) { |
0933840a JO |
9944 | if (pmu->nr_addr_filters) |
9945 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9946 | device_del(pmu->dev); | |
9947 | put_device(pmu->dev); | |
9948 | } | |
51676957 | 9949 | free_pmu_context(pmu); |
a9f97721 | 9950 | mutex_unlock(&pmus_lock); |
b0a873eb | 9951 | } |
c464c76e | 9952 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 9953 | |
cc34b98b MR |
9954 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
9955 | { | |
ccd41c86 | 9956 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
9957 | int ret; |
9958 | ||
9959 | if (!try_module_get(pmu->module)) | |
9960 | return -ENODEV; | |
ccd41c86 | 9961 | |
0c7296ca PZ |
9962 | /* |
9963 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
9964 | * for example, validate if the group fits on the PMU. Therefore, | |
9965 | * if this is a sibling event, acquire the ctx->mutex to protect | |
9966 | * the sibling_list. | |
9967 | */ | |
9968 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
9969 | /* |
9970 | * This ctx->mutex can nest when we're called through | |
9971 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
9972 | */ | |
9973 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
9974 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
9975 | BUG_ON(!ctx); |
9976 | } | |
9977 | ||
cc34b98b MR |
9978 | event->pmu = pmu; |
9979 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
9980 | |
9981 | if (ctx) | |
9982 | perf_event_ctx_unlock(event->group_leader, ctx); | |
9983 | ||
cc6795ae AM |
9984 | if (!ret) { |
9985 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && | |
9986 | event_has_any_exclude_flag(event)) { | |
9987 | if (event->destroy) | |
9988 | event->destroy(event); | |
9989 | ret = -EINVAL; | |
9990 | } | |
9991 | } | |
9992 | ||
cc34b98b MR |
9993 | if (ret) |
9994 | module_put(pmu->module); | |
9995 | ||
9996 | return ret; | |
9997 | } | |
9998 | ||
18ab2cd3 | 9999 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10000 | { |
85c617ab | 10001 | struct pmu *pmu; |
b0a873eb | 10002 | int idx; |
940c5b29 | 10003 | int ret; |
b0a873eb PZ |
10004 | |
10005 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10006 | |
40999312 KL |
10007 | /* Try parent's PMU first: */ |
10008 | if (event->parent && event->parent->pmu) { | |
10009 | pmu = event->parent->pmu; | |
10010 | ret = perf_try_init_event(pmu, event); | |
10011 | if (!ret) | |
10012 | goto unlock; | |
10013 | } | |
10014 | ||
2e80a82a PZ |
10015 | rcu_read_lock(); |
10016 | pmu = idr_find(&pmu_idr, event->attr.type); | |
10017 | rcu_read_unlock(); | |
940c5b29 | 10018 | if (pmu) { |
cc34b98b | 10019 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
10020 | if (ret) |
10021 | pmu = ERR_PTR(ret); | |
2e80a82a | 10022 | goto unlock; |
940c5b29 | 10023 | } |
2e80a82a | 10024 | |
b0a873eb | 10025 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 10026 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10027 | if (!ret) |
e5f4d339 | 10028 | goto unlock; |
76e1d904 | 10029 | |
b0a873eb PZ |
10030 | if (ret != -ENOENT) { |
10031 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10032 | goto unlock; |
f344011c | 10033 | } |
5c92d124 | 10034 | } |
e5f4d339 PZ |
10035 | pmu = ERR_PTR(-ENOENT); |
10036 | unlock: | |
b0a873eb | 10037 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10038 | |
4aeb0b42 | 10039 | return pmu; |
5c92d124 IM |
10040 | } |
10041 | ||
f2fb6bef KL |
10042 | static void attach_sb_event(struct perf_event *event) |
10043 | { | |
10044 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10045 | ||
10046 | raw_spin_lock(&pel->lock); | |
10047 | list_add_rcu(&event->sb_list, &pel->list); | |
10048 | raw_spin_unlock(&pel->lock); | |
10049 | } | |
10050 | ||
aab5b71e PZ |
10051 | /* |
10052 | * We keep a list of all !task (and therefore per-cpu) events | |
10053 | * that need to receive side-band records. | |
10054 | * | |
10055 | * This avoids having to scan all the various PMU per-cpu contexts | |
10056 | * looking for them. | |
10057 | */ | |
f2fb6bef KL |
10058 | static void account_pmu_sb_event(struct perf_event *event) |
10059 | { | |
a4f144eb | 10060 | if (is_sb_event(event)) |
f2fb6bef KL |
10061 | attach_sb_event(event); |
10062 | } | |
10063 | ||
4beb31f3 FW |
10064 | static void account_event_cpu(struct perf_event *event, int cpu) |
10065 | { | |
10066 | if (event->parent) | |
10067 | return; | |
10068 | ||
4beb31f3 FW |
10069 | if (is_cgroup_event(event)) |
10070 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10071 | } | |
10072 | ||
555e0c1e FW |
10073 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10074 | static void account_freq_event_nohz(void) | |
10075 | { | |
10076 | #ifdef CONFIG_NO_HZ_FULL | |
10077 | /* Lock so we don't race with concurrent unaccount */ | |
10078 | spin_lock(&nr_freq_lock); | |
10079 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10080 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10081 | spin_unlock(&nr_freq_lock); | |
10082 | #endif | |
10083 | } | |
10084 | ||
10085 | static void account_freq_event(void) | |
10086 | { | |
10087 | if (tick_nohz_full_enabled()) | |
10088 | account_freq_event_nohz(); | |
10089 | else | |
10090 | atomic_inc(&nr_freq_events); | |
10091 | } | |
10092 | ||
10093 | ||
766d6c07 FW |
10094 | static void account_event(struct perf_event *event) |
10095 | { | |
25432ae9 PZ |
10096 | bool inc = false; |
10097 | ||
4beb31f3 FW |
10098 | if (event->parent) |
10099 | return; | |
10100 | ||
766d6c07 | 10101 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10102 | inc = true; |
766d6c07 FW |
10103 | if (event->attr.mmap || event->attr.mmap_data) |
10104 | atomic_inc(&nr_mmap_events); | |
10105 | if (event->attr.comm) | |
10106 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10107 | if (event->attr.namespaces) |
10108 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10109 | if (event->attr.task) |
10110 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10111 | if (event->attr.freq) |
10112 | account_freq_event(); | |
45ac1403 AH |
10113 | if (event->attr.context_switch) { |
10114 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10115 | inc = true; |
45ac1403 | 10116 | } |
4beb31f3 | 10117 | if (has_branch_stack(event)) |
25432ae9 | 10118 | inc = true; |
4beb31f3 | 10119 | if (is_cgroup_event(event)) |
25432ae9 | 10120 | inc = true; |
76193a94 SL |
10121 | if (event->attr.ksymbol) |
10122 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10123 | if (event->attr.bpf_event) |
10124 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10125 | |
9107c89e | 10126 | if (inc) { |
5bce9db1 AS |
10127 | /* |
10128 | * We need the mutex here because static_branch_enable() | |
10129 | * must complete *before* the perf_sched_count increment | |
10130 | * becomes visible. | |
10131 | */ | |
9107c89e PZ |
10132 | if (atomic_inc_not_zero(&perf_sched_count)) |
10133 | goto enabled; | |
10134 | ||
10135 | mutex_lock(&perf_sched_mutex); | |
10136 | if (!atomic_read(&perf_sched_count)) { | |
10137 | static_branch_enable(&perf_sched_events); | |
10138 | /* | |
10139 | * Guarantee that all CPUs observe they key change and | |
10140 | * call the perf scheduling hooks before proceeding to | |
10141 | * install events that need them. | |
10142 | */ | |
0809d954 | 10143 | synchronize_rcu(); |
9107c89e PZ |
10144 | } |
10145 | /* | |
10146 | * Now that we have waited for the sync_sched(), allow further | |
10147 | * increments to by-pass the mutex. | |
10148 | */ | |
10149 | atomic_inc(&perf_sched_count); | |
10150 | mutex_unlock(&perf_sched_mutex); | |
10151 | } | |
10152 | enabled: | |
4beb31f3 FW |
10153 | |
10154 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10155 | |
10156 | account_pmu_sb_event(event); | |
766d6c07 FW |
10157 | } |
10158 | ||
0793a61d | 10159 | /* |
788faab7 | 10160 | * Allocate and initialize an event structure |
0793a61d | 10161 | */ |
cdd6c482 | 10162 | static struct perf_event * |
c3f00c70 | 10163 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10164 | struct task_struct *task, |
10165 | struct perf_event *group_leader, | |
10166 | struct perf_event *parent_event, | |
4dc0da86 | 10167 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10168 | void *context, int cgroup_fd) |
0793a61d | 10169 | { |
51b0fe39 | 10170 | struct pmu *pmu; |
cdd6c482 IM |
10171 | struct perf_event *event; |
10172 | struct hw_perf_event *hwc; | |
90983b16 | 10173 | long err = -EINVAL; |
0793a61d | 10174 | |
66832eb4 ON |
10175 | if ((unsigned)cpu >= nr_cpu_ids) { |
10176 | if (!task || cpu != -1) | |
10177 | return ERR_PTR(-EINVAL); | |
10178 | } | |
10179 | ||
c3f00c70 | 10180 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10181 | if (!event) |
d5d2bc0d | 10182 | return ERR_PTR(-ENOMEM); |
0793a61d | 10183 | |
04289bb9 | 10184 | /* |
cdd6c482 | 10185 | * Single events are their own group leaders, with an |
04289bb9 IM |
10186 | * empty sibling list: |
10187 | */ | |
10188 | if (!group_leader) | |
cdd6c482 | 10189 | group_leader = event; |
04289bb9 | 10190 | |
cdd6c482 IM |
10191 | mutex_init(&event->child_mutex); |
10192 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10193 | |
cdd6c482 IM |
10194 | INIT_LIST_HEAD(&event->event_entry); |
10195 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10196 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10197 | init_event_group(event); |
10c6db11 | 10198 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10199 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10200 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10201 | INIT_HLIST_NODE(&event->hlist_entry); |
10202 | ||
10c6db11 | 10203 | |
cdd6c482 | 10204 | init_waitqueue_head(&event->waitq); |
e360adbe | 10205 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10206 | |
cdd6c482 | 10207 | mutex_init(&event->mmap_mutex); |
375637bc | 10208 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10209 | |
a6fa941d | 10210 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10211 | event->cpu = cpu; |
10212 | event->attr = *attr; | |
10213 | event->group_leader = group_leader; | |
10214 | event->pmu = NULL; | |
cdd6c482 | 10215 | event->oncpu = -1; |
a96bbc16 | 10216 | |
cdd6c482 | 10217 | event->parent = parent_event; |
b84fbc9f | 10218 | |
17cf22c3 | 10219 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10220 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10221 | |
cdd6c482 | 10222 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10223 | |
d580ff86 PZ |
10224 | if (task) { |
10225 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10226 | /* |
50f16a8b PZ |
10227 | * XXX pmu::event_init needs to know what task to account to |
10228 | * and we cannot use the ctx information because we need the | |
10229 | * pmu before we get a ctx. | |
d580ff86 | 10230 | */ |
621b6d2e | 10231 | get_task_struct(task); |
50f16a8b | 10232 | event->hw.target = task; |
d580ff86 PZ |
10233 | } |
10234 | ||
34f43927 PZ |
10235 | event->clock = &local_clock; |
10236 | if (parent_event) | |
10237 | event->clock = parent_event->clock; | |
10238 | ||
4dc0da86 | 10239 | if (!overflow_handler && parent_event) { |
b326e956 | 10240 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10241 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10242 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
10243 | if (overflow_handler == bpf_overflow_handler) { |
10244 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
10245 | ||
10246 | if (IS_ERR(prog)) { | |
10247 | err = PTR_ERR(prog); | |
10248 | goto err_ns; | |
10249 | } | |
10250 | event->prog = prog; | |
10251 | event->orig_overflow_handler = | |
10252 | parent_event->orig_overflow_handler; | |
10253 | } | |
10254 | #endif | |
4dc0da86 | 10255 | } |
66832eb4 | 10256 | |
1879445d WN |
10257 | if (overflow_handler) { |
10258 | event->overflow_handler = overflow_handler; | |
10259 | event->overflow_handler_context = context; | |
9ecda41a WN |
10260 | } else if (is_write_backward(event)){ |
10261 | event->overflow_handler = perf_event_output_backward; | |
10262 | event->overflow_handler_context = NULL; | |
1879445d | 10263 | } else { |
9ecda41a | 10264 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10265 | event->overflow_handler_context = NULL; |
10266 | } | |
97eaf530 | 10267 | |
0231bb53 | 10268 | perf_event__state_init(event); |
a86ed508 | 10269 | |
4aeb0b42 | 10270 | pmu = NULL; |
b8e83514 | 10271 | |
cdd6c482 | 10272 | hwc = &event->hw; |
bd2b5b12 | 10273 | hwc->sample_period = attr->sample_period; |
0d48696f | 10274 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10275 | hwc->sample_period = 1; |
eced1dfc | 10276 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10277 | |
e7850595 | 10278 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10279 | |
2023b359 | 10280 | /* |
ba5213ae PZ |
10281 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10282 | * See perf_output_read(). | |
2023b359 | 10283 | */ |
ba5213ae | 10284 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10285 | goto err_ns; |
a46a2300 YZ |
10286 | |
10287 | if (!has_branch_stack(event)) | |
10288 | event->attr.branch_sample_type = 0; | |
2023b359 | 10289 | |
79dff51e MF |
10290 | if (cgroup_fd != -1) { |
10291 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10292 | if (err) | |
10293 | goto err_ns; | |
10294 | } | |
10295 | ||
b0a873eb | 10296 | pmu = perf_init_event(event); |
85c617ab | 10297 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10298 | err = PTR_ERR(pmu); |
90983b16 | 10299 | goto err_ns; |
621a01ea | 10300 | } |
d5d2bc0d | 10301 | |
bed5b25a AS |
10302 | err = exclusive_event_init(event); |
10303 | if (err) | |
10304 | goto err_pmu; | |
10305 | ||
375637bc AS |
10306 | if (has_addr_filter(event)) { |
10307 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
10308 | sizeof(unsigned long), | |
10309 | GFP_KERNEL); | |
36cc2b92 DC |
10310 | if (!event->addr_filters_offs) { |
10311 | err = -ENOMEM; | |
375637bc | 10312 | goto err_per_task; |
36cc2b92 | 10313 | } |
375637bc AS |
10314 | |
10315 | /* force hw sync on the address filters */ | |
10316 | event->addr_filters_gen = 1; | |
10317 | } | |
10318 | ||
cdd6c482 | 10319 | if (!event->parent) { |
927c7a9e | 10320 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 10321 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 10322 | if (err) |
375637bc | 10323 | goto err_addr_filters; |
d010b332 | 10324 | } |
f344011c | 10325 | } |
9ee318a7 | 10326 | |
927a5570 AS |
10327 | /* symmetric to unaccount_event() in _free_event() */ |
10328 | account_event(event); | |
10329 | ||
cdd6c482 | 10330 | return event; |
90983b16 | 10331 | |
375637bc AS |
10332 | err_addr_filters: |
10333 | kfree(event->addr_filters_offs); | |
10334 | ||
bed5b25a AS |
10335 | err_per_task: |
10336 | exclusive_event_destroy(event); | |
10337 | ||
90983b16 FW |
10338 | err_pmu: |
10339 | if (event->destroy) | |
10340 | event->destroy(event); | |
c464c76e | 10341 | module_put(pmu->module); |
90983b16 | 10342 | err_ns: |
79dff51e MF |
10343 | if (is_cgroup_event(event)) |
10344 | perf_detach_cgroup(event); | |
90983b16 FW |
10345 | if (event->ns) |
10346 | put_pid_ns(event->ns); | |
621b6d2e PB |
10347 | if (event->hw.target) |
10348 | put_task_struct(event->hw.target); | |
90983b16 FW |
10349 | kfree(event); |
10350 | ||
10351 | return ERR_PTR(err); | |
0793a61d TG |
10352 | } |
10353 | ||
cdd6c482 IM |
10354 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
10355 | struct perf_event_attr *attr) | |
974802ea | 10356 | { |
974802ea | 10357 | u32 size; |
cdf8073d | 10358 | int ret; |
974802ea | 10359 | |
96d4f267 | 10360 | if (!access_ok(uattr, PERF_ATTR_SIZE_VER0)) |
974802ea PZ |
10361 | return -EFAULT; |
10362 | ||
10363 | /* | |
10364 | * zero the full structure, so that a short copy will be nice. | |
10365 | */ | |
10366 | memset(attr, 0, sizeof(*attr)); | |
10367 | ||
10368 | ret = get_user(size, &uattr->size); | |
10369 | if (ret) | |
10370 | return ret; | |
10371 | ||
10372 | if (size > PAGE_SIZE) /* silly large */ | |
10373 | goto err_size; | |
10374 | ||
10375 | if (!size) /* abi compat */ | |
10376 | size = PERF_ATTR_SIZE_VER0; | |
10377 | ||
10378 | if (size < PERF_ATTR_SIZE_VER0) | |
10379 | goto err_size; | |
10380 | ||
10381 | /* | |
10382 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
10383 | * ensure all the unknown bits are 0 - i.e. new |
10384 | * user-space does not rely on any kernel feature | |
10385 | * extensions we dont know about yet. | |
974802ea PZ |
10386 | */ |
10387 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
10388 | unsigned char __user *addr; |
10389 | unsigned char __user *end; | |
10390 | unsigned char val; | |
974802ea | 10391 | |
cdf8073d IS |
10392 | addr = (void __user *)uattr + sizeof(*attr); |
10393 | end = (void __user *)uattr + size; | |
974802ea | 10394 | |
cdf8073d | 10395 | for (; addr < end; addr++) { |
974802ea PZ |
10396 | ret = get_user(val, addr); |
10397 | if (ret) | |
10398 | return ret; | |
10399 | if (val) | |
10400 | goto err_size; | |
10401 | } | |
b3e62e35 | 10402 | size = sizeof(*attr); |
974802ea PZ |
10403 | } |
10404 | ||
10405 | ret = copy_from_user(attr, uattr, size); | |
10406 | if (ret) | |
10407 | return -EFAULT; | |
10408 | ||
f12f42ac MX |
10409 | attr->size = size; |
10410 | ||
cd757645 | 10411 | if (attr->__reserved_1) |
974802ea PZ |
10412 | return -EINVAL; |
10413 | ||
10414 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10415 | return -EINVAL; | |
10416 | ||
10417 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10418 | return -EINVAL; | |
10419 | ||
bce38cd5 SE |
10420 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10421 | u64 mask = attr->branch_sample_type; | |
10422 | ||
10423 | /* only using defined bits */ | |
10424 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10425 | return -EINVAL; | |
10426 | ||
10427 | /* at least one branch bit must be set */ | |
10428 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10429 | return -EINVAL; | |
10430 | ||
bce38cd5 SE |
10431 | /* propagate priv level, when not set for branch */ |
10432 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10433 | ||
10434 | /* exclude_kernel checked on syscall entry */ | |
10435 | if (!attr->exclude_kernel) | |
10436 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10437 | ||
10438 | if (!attr->exclude_user) | |
10439 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10440 | ||
10441 | if (!attr->exclude_hv) | |
10442 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10443 | /* | |
10444 | * adjust user setting (for HW filter setup) | |
10445 | */ | |
10446 | attr->branch_sample_type = mask; | |
10447 | } | |
e712209a SE |
10448 | /* privileged levels capture (kernel, hv): check permissions */ |
10449 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
10450 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
10451 | return -EACCES; | |
bce38cd5 | 10452 | } |
4018994f | 10453 | |
c5ebcedb | 10454 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10455 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10456 | if (ret) |
10457 | return ret; | |
10458 | } | |
10459 | ||
10460 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10461 | if (!arch_perf_have_user_stack_dump()) | |
10462 | return -ENOSYS; | |
10463 | ||
10464 | /* | |
10465 | * We have __u32 type for the size, but so far | |
10466 | * we can only use __u16 as maximum due to the | |
10467 | * __u16 sample size limit. | |
10468 | */ | |
10469 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 10470 | return -EINVAL; |
c5ebcedb | 10471 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 10472 | return -EINVAL; |
c5ebcedb | 10473 | } |
4018994f | 10474 | |
5f970521 JO |
10475 | if (!attr->sample_max_stack) |
10476 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
10477 | ||
60e2364e SE |
10478 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10479 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10480 | out: |
10481 | return ret; | |
10482 | ||
10483 | err_size: | |
10484 | put_user(sizeof(*attr), &uattr->size); | |
10485 | ret = -E2BIG; | |
10486 | goto out; | |
10487 | } | |
10488 | ||
ac9721f3 PZ |
10489 | static int |
10490 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 10491 | { |
b69cf536 | 10492 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
10493 | int ret = -EINVAL; |
10494 | ||
ac9721f3 | 10495 | if (!output_event) |
a4be7c27 PZ |
10496 | goto set; |
10497 | ||
ac9721f3 PZ |
10498 | /* don't allow circular references */ |
10499 | if (event == output_event) | |
a4be7c27 PZ |
10500 | goto out; |
10501 | ||
0f139300 PZ |
10502 | /* |
10503 | * Don't allow cross-cpu buffers | |
10504 | */ | |
10505 | if (output_event->cpu != event->cpu) | |
10506 | goto out; | |
10507 | ||
10508 | /* | |
76369139 | 10509 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
10510 | */ |
10511 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
10512 | goto out; | |
10513 | ||
34f43927 PZ |
10514 | /* |
10515 | * Mixing clocks in the same buffer is trouble you don't need. | |
10516 | */ | |
10517 | if (output_event->clock != event->clock) | |
10518 | goto out; | |
10519 | ||
9ecda41a WN |
10520 | /* |
10521 | * Either writing ring buffer from beginning or from end. | |
10522 | * Mixing is not allowed. | |
10523 | */ | |
10524 | if (is_write_backward(output_event) != is_write_backward(event)) | |
10525 | goto out; | |
10526 | ||
45bfb2e5 PZ |
10527 | /* |
10528 | * If both events generate aux data, they must be on the same PMU | |
10529 | */ | |
10530 | if (has_aux(event) && has_aux(output_event) && | |
10531 | event->pmu != output_event->pmu) | |
10532 | goto out; | |
10533 | ||
a4be7c27 | 10534 | set: |
cdd6c482 | 10535 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
10536 | /* Can't redirect output if we've got an active mmap() */ |
10537 | if (atomic_read(&event->mmap_count)) | |
10538 | goto unlock; | |
a4be7c27 | 10539 | |
ac9721f3 | 10540 | if (output_event) { |
76369139 FW |
10541 | /* get the rb we want to redirect to */ |
10542 | rb = ring_buffer_get(output_event); | |
10543 | if (!rb) | |
ac9721f3 | 10544 | goto unlock; |
a4be7c27 PZ |
10545 | } |
10546 | ||
b69cf536 | 10547 | ring_buffer_attach(event, rb); |
9bb5d40c | 10548 | |
a4be7c27 | 10549 | ret = 0; |
ac9721f3 PZ |
10550 | unlock: |
10551 | mutex_unlock(&event->mmap_mutex); | |
10552 | ||
a4be7c27 | 10553 | out: |
a4be7c27 PZ |
10554 | return ret; |
10555 | } | |
10556 | ||
f63a8daa PZ |
10557 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
10558 | { | |
10559 | if (b < a) | |
10560 | swap(a, b); | |
10561 | ||
10562 | mutex_lock(a); | |
10563 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
10564 | } | |
10565 | ||
34f43927 PZ |
10566 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
10567 | { | |
10568 | bool nmi_safe = false; | |
10569 | ||
10570 | switch (clk_id) { | |
10571 | case CLOCK_MONOTONIC: | |
10572 | event->clock = &ktime_get_mono_fast_ns; | |
10573 | nmi_safe = true; | |
10574 | break; | |
10575 | ||
10576 | case CLOCK_MONOTONIC_RAW: | |
10577 | event->clock = &ktime_get_raw_fast_ns; | |
10578 | nmi_safe = true; | |
10579 | break; | |
10580 | ||
10581 | case CLOCK_REALTIME: | |
10582 | event->clock = &ktime_get_real_ns; | |
10583 | break; | |
10584 | ||
10585 | case CLOCK_BOOTTIME: | |
10586 | event->clock = &ktime_get_boot_ns; | |
10587 | break; | |
10588 | ||
10589 | case CLOCK_TAI: | |
10590 | event->clock = &ktime_get_tai_ns; | |
10591 | break; | |
10592 | ||
10593 | default: | |
10594 | return -EINVAL; | |
10595 | } | |
10596 | ||
10597 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
10598 | return -EINVAL; | |
10599 | ||
10600 | return 0; | |
10601 | } | |
10602 | ||
321027c1 PZ |
10603 | /* |
10604 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
10605 | * mutexes. | |
10606 | */ | |
10607 | static struct perf_event_context * | |
10608 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
10609 | struct perf_event_context *ctx) | |
10610 | { | |
10611 | struct perf_event_context *gctx; | |
10612 | ||
10613 | again: | |
10614 | rcu_read_lock(); | |
10615 | gctx = READ_ONCE(group_leader->ctx); | |
10616 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
10617 | rcu_read_unlock(); | |
10618 | goto again; | |
10619 | } | |
10620 | rcu_read_unlock(); | |
10621 | ||
10622 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
10623 | ||
10624 | if (group_leader->ctx != gctx) { | |
10625 | mutex_unlock(&ctx->mutex); | |
10626 | mutex_unlock(&gctx->mutex); | |
10627 | put_ctx(gctx); | |
10628 | goto again; | |
10629 | } | |
10630 | ||
10631 | return gctx; | |
10632 | } | |
10633 | ||
0793a61d | 10634 | /** |
cdd6c482 | 10635 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 10636 | * |
cdd6c482 | 10637 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 10638 | * @pid: target pid |
9f66a381 | 10639 | * @cpu: target cpu |
cdd6c482 | 10640 | * @group_fd: group leader event fd |
0793a61d | 10641 | */ |
cdd6c482 IM |
10642 | SYSCALL_DEFINE5(perf_event_open, |
10643 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 10644 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 10645 | { |
b04243ef PZ |
10646 | struct perf_event *group_leader = NULL, *output_event = NULL; |
10647 | struct perf_event *event, *sibling; | |
cdd6c482 | 10648 | struct perf_event_attr attr; |
f63a8daa | 10649 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 10650 | struct file *event_file = NULL; |
2903ff01 | 10651 | struct fd group = {NULL, 0}; |
38a81da2 | 10652 | struct task_struct *task = NULL; |
89a1e187 | 10653 | struct pmu *pmu; |
ea635c64 | 10654 | int event_fd; |
b04243ef | 10655 | int move_group = 0; |
dc86cabe | 10656 | int err; |
a21b0b35 | 10657 | int f_flags = O_RDWR; |
79dff51e | 10658 | int cgroup_fd = -1; |
0793a61d | 10659 | |
2743a5b0 | 10660 | /* for future expandability... */ |
e5d1367f | 10661 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10662 | return -EINVAL; |
10663 | ||
dc86cabe IM |
10664 | err = perf_copy_attr(attr_uptr, &attr); |
10665 | if (err) | |
10666 | return err; | |
eab656ae | 10667 | |
0764771d PZ |
10668 | if (!attr.exclude_kernel) { |
10669 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10670 | return -EACCES; | |
10671 | } | |
10672 | ||
e4222673 HB |
10673 | if (attr.namespaces) { |
10674 | if (!capable(CAP_SYS_ADMIN)) | |
10675 | return -EACCES; | |
10676 | } | |
10677 | ||
df58ab24 | 10678 | if (attr.freq) { |
cdd6c482 | 10679 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 10680 | return -EINVAL; |
0819b2e3 PZ |
10681 | } else { |
10682 | if (attr.sample_period & (1ULL << 63)) | |
10683 | return -EINVAL; | |
df58ab24 PZ |
10684 | } |
10685 | ||
fc7ce9c7 KL |
10686 | /* Only privileged users can get physical addresses */ |
10687 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && | |
10688 | perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10689 | return -EACCES; | |
10690 | ||
e5d1367f SE |
10691 | /* |
10692 | * In cgroup mode, the pid argument is used to pass the fd | |
10693 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
10694 | * designates the cpu on which to monitor threads from that | |
10695 | * cgroup. | |
10696 | */ | |
10697 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
10698 | return -EINVAL; | |
10699 | ||
a21b0b35 YD |
10700 | if (flags & PERF_FLAG_FD_CLOEXEC) |
10701 | f_flags |= O_CLOEXEC; | |
10702 | ||
10703 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
10704 | if (event_fd < 0) |
10705 | return event_fd; | |
10706 | ||
ac9721f3 | 10707 | if (group_fd != -1) { |
2903ff01 AV |
10708 | err = perf_fget_light(group_fd, &group); |
10709 | if (err) | |
d14b12d7 | 10710 | goto err_fd; |
2903ff01 | 10711 | group_leader = group.file->private_data; |
ac9721f3 PZ |
10712 | if (flags & PERF_FLAG_FD_OUTPUT) |
10713 | output_event = group_leader; | |
10714 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
10715 | group_leader = NULL; | |
10716 | } | |
10717 | ||
e5d1367f | 10718 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
10719 | task = find_lively_task_by_vpid(pid); |
10720 | if (IS_ERR(task)) { | |
10721 | err = PTR_ERR(task); | |
10722 | goto err_group_fd; | |
10723 | } | |
10724 | } | |
10725 | ||
1f4ee503 PZ |
10726 | if (task && group_leader && |
10727 | group_leader->attr.inherit != attr.inherit) { | |
10728 | err = -EINVAL; | |
10729 | goto err_task; | |
10730 | } | |
10731 | ||
79c9ce57 PZ |
10732 | if (task) { |
10733 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
10734 | if (err) | |
e5aeee51 | 10735 | goto err_task; |
79c9ce57 PZ |
10736 | |
10737 | /* | |
10738 | * Reuse ptrace permission checks for now. | |
10739 | * | |
10740 | * We must hold cred_guard_mutex across this and any potential | |
10741 | * perf_install_in_context() call for this new event to | |
10742 | * serialize against exec() altering our credentials (and the | |
10743 | * perf_event_exit_task() that could imply). | |
10744 | */ | |
10745 | err = -EACCES; | |
10746 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
10747 | goto err_cred; | |
10748 | } | |
10749 | ||
79dff51e MF |
10750 | if (flags & PERF_FLAG_PID_CGROUP) |
10751 | cgroup_fd = pid; | |
10752 | ||
4dc0da86 | 10753 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 10754 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
10755 | if (IS_ERR(event)) { |
10756 | err = PTR_ERR(event); | |
79c9ce57 | 10757 | goto err_cred; |
d14b12d7 SE |
10758 | } |
10759 | ||
53b25335 VW |
10760 | if (is_sampling_event(event)) { |
10761 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 10762 | err = -EOPNOTSUPP; |
53b25335 VW |
10763 | goto err_alloc; |
10764 | } | |
10765 | } | |
10766 | ||
89a1e187 PZ |
10767 | /* |
10768 | * Special case software events and allow them to be part of | |
10769 | * any hardware group. | |
10770 | */ | |
10771 | pmu = event->pmu; | |
b04243ef | 10772 | |
34f43927 PZ |
10773 | if (attr.use_clockid) { |
10774 | err = perf_event_set_clock(event, attr.clockid); | |
10775 | if (err) | |
10776 | goto err_alloc; | |
10777 | } | |
10778 | ||
4ff6a8de DCC |
10779 | if (pmu->task_ctx_nr == perf_sw_context) |
10780 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
10781 | ||
a1150c20 SL |
10782 | if (group_leader) { |
10783 | if (is_software_event(event) && | |
10784 | !in_software_context(group_leader)) { | |
b04243ef | 10785 | /* |
a1150c20 SL |
10786 | * If the event is a sw event, but the group_leader |
10787 | * is on hw context. | |
b04243ef | 10788 | * |
a1150c20 SL |
10789 | * Allow the addition of software events to hw |
10790 | * groups, this is safe because software events | |
10791 | * never fail to schedule. | |
b04243ef | 10792 | */ |
a1150c20 SL |
10793 | pmu = group_leader->ctx->pmu; |
10794 | } else if (!is_software_event(event) && | |
10795 | is_software_event(group_leader) && | |
4ff6a8de | 10796 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
10797 | /* |
10798 | * In case the group is a pure software group, and we | |
10799 | * try to add a hardware event, move the whole group to | |
10800 | * the hardware context. | |
10801 | */ | |
10802 | move_group = 1; | |
10803 | } | |
10804 | } | |
89a1e187 PZ |
10805 | |
10806 | /* | |
10807 | * Get the target context (task or percpu): | |
10808 | */ | |
4af57ef2 | 10809 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
10810 | if (IS_ERR(ctx)) { |
10811 | err = PTR_ERR(ctx); | |
c6be5a5c | 10812 | goto err_alloc; |
89a1e187 PZ |
10813 | } |
10814 | ||
bed5b25a AS |
10815 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
10816 | err = -EBUSY; | |
10817 | goto err_context; | |
10818 | } | |
10819 | ||
ccff286d | 10820 | /* |
cdd6c482 | 10821 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 10822 | */ |
ac9721f3 | 10823 | if (group_leader) { |
dc86cabe | 10824 | err = -EINVAL; |
04289bb9 | 10825 | |
04289bb9 | 10826 | /* |
ccff286d IM |
10827 | * Do not allow a recursive hierarchy (this new sibling |
10828 | * becoming part of another group-sibling): | |
10829 | */ | |
10830 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 10831 | goto err_context; |
34f43927 PZ |
10832 | |
10833 | /* All events in a group should have the same clock */ | |
10834 | if (group_leader->clock != event->clock) | |
10835 | goto err_context; | |
10836 | ||
ccff286d | 10837 | /* |
64aee2a9 MR |
10838 | * Make sure we're both events for the same CPU; |
10839 | * grouping events for different CPUs is broken; since | |
10840 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 10841 | */ |
64aee2a9 MR |
10842 | if (group_leader->cpu != event->cpu) |
10843 | goto err_context; | |
c3c87e77 | 10844 | |
64aee2a9 MR |
10845 | /* |
10846 | * Make sure we're both on the same task, or both | |
10847 | * per-CPU events. | |
10848 | */ | |
10849 | if (group_leader->ctx->task != ctx->task) | |
10850 | goto err_context; | |
10851 | ||
10852 | /* | |
10853 | * Do not allow to attach to a group in a different task | |
10854 | * or CPU context. If we're moving SW events, we'll fix | |
10855 | * this up later, so allow that. | |
10856 | */ | |
10857 | if (!move_group && group_leader->ctx != ctx) | |
10858 | goto err_context; | |
b04243ef | 10859 | |
3b6f9e5c PM |
10860 | /* |
10861 | * Only a group leader can be exclusive or pinned | |
10862 | */ | |
0d48696f | 10863 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 10864 | goto err_context; |
ac9721f3 PZ |
10865 | } |
10866 | ||
10867 | if (output_event) { | |
10868 | err = perf_event_set_output(event, output_event); | |
10869 | if (err) | |
c3f00c70 | 10870 | goto err_context; |
ac9721f3 | 10871 | } |
0793a61d | 10872 | |
a21b0b35 YD |
10873 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
10874 | f_flags); | |
ea635c64 AV |
10875 | if (IS_ERR(event_file)) { |
10876 | err = PTR_ERR(event_file); | |
201c2f85 | 10877 | event_file = NULL; |
c3f00c70 | 10878 | goto err_context; |
ea635c64 | 10879 | } |
9b51f66d | 10880 | |
b04243ef | 10881 | if (move_group) { |
321027c1 PZ |
10882 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
10883 | ||
84c4e620 PZ |
10884 | if (gctx->task == TASK_TOMBSTONE) { |
10885 | err = -ESRCH; | |
10886 | goto err_locked; | |
10887 | } | |
321027c1 PZ |
10888 | |
10889 | /* | |
10890 | * Check if we raced against another sys_perf_event_open() call | |
10891 | * moving the software group underneath us. | |
10892 | */ | |
10893 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
10894 | /* | |
10895 | * If someone moved the group out from under us, check | |
10896 | * if this new event wound up on the same ctx, if so | |
10897 | * its the regular !move_group case, otherwise fail. | |
10898 | */ | |
10899 | if (gctx != ctx) { | |
10900 | err = -EINVAL; | |
10901 | goto err_locked; | |
10902 | } else { | |
10903 | perf_event_ctx_unlock(group_leader, gctx); | |
10904 | move_group = 0; | |
10905 | } | |
10906 | } | |
f55fc2a5 PZ |
10907 | } else { |
10908 | mutex_lock(&ctx->mutex); | |
10909 | } | |
10910 | ||
84c4e620 PZ |
10911 | if (ctx->task == TASK_TOMBSTONE) { |
10912 | err = -ESRCH; | |
10913 | goto err_locked; | |
10914 | } | |
10915 | ||
a723968c PZ |
10916 | if (!perf_event_validate_size(event)) { |
10917 | err = -E2BIG; | |
10918 | goto err_locked; | |
10919 | } | |
10920 | ||
a63fbed7 TG |
10921 | if (!task) { |
10922 | /* | |
10923 | * Check if the @cpu we're creating an event for is online. | |
10924 | * | |
10925 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
10926 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
10927 | */ | |
10928 | struct perf_cpu_context *cpuctx = | |
10929 | container_of(ctx, struct perf_cpu_context, ctx); | |
10930 | ||
10931 | if (!cpuctx->online) { | |
10932 | err = -ENODEV; | |
10933 | goto err_locked; | |
10934 | } | |
10935 | } | |
10936 | ||
10937 | ||
f55fc2a5 PZ |
10938 | /* |
10939 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
10940 | * because we need to serialize with concurrent event creation. | |
10941 | */ | |
10942 | if (!exclusive_event_installable(event, ctx)) { | |
10943 | /* exclusive and group stuff are assumed mutually exclusive */ | |
10944 | WARN_ON_ONCE(move_group); | |
f63a8daa | 10945 | |
f55fc2a5 PZ |
10946 | err = -EBUSY; |
10947 | goto err_locked; | |
10948 | } | |
f63a8daa | 10949 | |
f55fc2a5 PZ |
10950 | WARN_ON_ONCE(ctx->parent_ctx); |
10951 | ||
79c9ce57 PZ |
10952 | /* |
10953 | * This is the point on no return; we cannot fail hereafter. This is | |
10954 | * where we start modifying current state. | |
10955 | */ | |
10956 | ||
f55fc2a5 | 10957 | if (move_group) { |
f63a8daa PZ |
10958 | /* |
10959 | * See perf_event_ctx_lock() for comments on the details | |
10960 | * of swizzling perf_event::ctx. | |
10961 | */ | |
45a0e07a | 10962 | perf_remove_from_context(group_leader, 0); |
279b5165 | 10963 | put_ctx(gctx); |
0231bb53 | 10964 | |
edb39592 | 10965 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 10966 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
10967 | put_ctx(gctx); |
10968 | } | |
b04243ef | 10969 | |
f63a8daa PZ |
10970 | /* |
10971 | * Wait for everybody to stop referencing the events through | |
10972 | * the old lists, before installing it on new lists. | |
10973 | */ | |
0cda4c02 | 10974 | synchronize_rcu(); |
f63a8daa | 10975 | |
8f95b435 PZI |
10976 | /* |
10977 | * Install the group siblings before the group leader. | |
10978 | * | |
10979 | * Because a group leader will try and install the entire group | |
10980 | * (through the sibling list, which is still in-tact), we can | |
10981 | * end up with siblings installed in the wrong context. | |
10982 | * | |
10983 | * By installing siblings first we NO-OP because they're not | |
10984 | * reachable through the group lists. | |
10985 | */ | |
edb39592 | 10986 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 10987 | perf_event__state_init(sibling); |
9fc81d87 | 10988 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
10989 | get_ctx(ctx); |
10990 | } | |
8f95b435 PZI |
10991 | |
10992 | /* | |
10993 | * Removing from the context ends up with disabled | |
10994 | * event. What we want here is event in the initial | |
10995 | * startup state, ready to be add into new context. | |
10996 | */ | |
10997 | perf_event__state_init(group_leader); | |
10998 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
10999 | get_ctx(ctx); | |
bed5b25a AS |
11000 | } |
11001 | ||
f73e22ab PZ |
11002 | /* |
11003 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11004 | * that we're serialized against further additions and before | |
11005 | * perf_install_in_context() which is the point the event is active and | |
11006 | * can use these values. | |
11007 | */ | |
11008 | perf_event__header_size(event); | |
11009 | perf_event__id_header_size(event); | |
11010 | ||
78cd2c74 PZ |
11011 | event->owner = current; |
11012 | ||
e2d37cd2 | 11013 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11014 | perf_unpin_context(ctx); |
f63a8daa | 11015 | |
f55fc2a5 | 11016 | if (move_group) |
321027c1 | 11017 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11018 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11019 | |
79c9ce57 PZ |
11020 | if (task) { |
11021 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11022 | put_task_struct(task); | |
11023 | } | |
11024 | ||
cdd6c482 IM |
11025 | mutex_lock(¤t->perf_event_mutex); |
11026 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11027 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11028 | |
8a49542c PZ |
11029 | /* |
11030 | * Drop the reference on the group_event after placing the | |
11031 | * new event on the sibling_list. This ensures destruction | |
11032 | * of the group leader will find the pointer to itself in | |
11033 | * perf_group_detach(). | |
11034 | */ | |
2903ff01 | 11035 | fdput(group); |
ea635c64 AV |
11036 | fd_install(event_fd, event_file); |
11037 | return event_fd; | |
0793a61d | 11038 | |
f55fc2a5 PZ |
11039 | err_locked: |
11040 | if (move_group) | |
321027c1 | 11041 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11042 | mutex_unlock(&ctx->mutex); |
11043 | /* err_file: */ | |
11044 | fput(event_file); | |
c3f00c70 | 11045 | err_context: |
fe4b04fa | 11046 | perf_unpin_context(ctx); |
ea635c64 | 11047 | put_ctx(ctx); |
c6be5a5c | 11048 | err_alloc: |
13005627 PZ |
11049 | /* |
11050 | * If event_file is set, the fput() above will have called ->release() | |
11051 | * and that will take care of freeing the event. | |
11052 | */ | |
11053 | if (!event_file) | |
11054 | free_event(event); | |
79c9ce57 PZ |
11055 | err_cred: |
11056 | if (task) | |
11057 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11058 | err_task: |
e7d0bc04 PZ |
11059 | if (task) |
11060 | put_task_struct(task); | |
89a1e187 | 11061 | err_group_fd: |
2903ff01 | 11062 | fdput(group); |
ea635c64 AV |
11063 | err_fd: |
11064 | put_unused_fd(event_fd); | |
dc86cabe | 11065 | return err; |
0793a61d TG |
11066 | } |
11067 | ||
fb0459d7 AV |
11068 | /** |
11069 | * perf_event_create_kernel_counter | |
11070 | * | |
11071 | * @attr: attributes of the counter to create | |
11072 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11073 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11074 | */ |
11075 | struct perf_event * | |
11076 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11077 | struct task_struct *task, |
4dc0da86 AK |
11078 | perf_overflow_handler_t overflow_handler, |
11079 | void *context) | |
fb0459d7 | 11080 | { |
fb0459d7 | 11081 | struct perf_event_context *ctx; |
c3f00c70 | 11082 | struct perf_event *event; |
fb0459d7 | 11083 | int err; |
d859e29f | 11084 | |
fb0459d7 AV |
11085 | /* |
11086 | * Get the target context (task or percpu): | |
11087 | */ | |
d859e29f | 11088 | |
4dc0da86 | 11089 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11090 | overflow_handler, context, -1); |
c3f00c70 PZ |
11091 | if (IS_ERR(event)) { |
11092 | err = PTR_ERR(event); | |
11093 | goto err; | |
11094 | } | |
d859e29f | 11095 | |
f8697762 | 11096 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11097 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11098 | |
4af57ef2 | 11099 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11100 | if (IS_ERR(ctx)) { |
11101 | err = PTR_ERR(ctx); | |
c3f00c70 | 11102 | goto err_free; |
d859e29f | 11103 | } |
fb0459d7 | 11104 | |
fb0459d7 AV |
11105 | WARN_ON_ONCE(ctx->parent_ctx); |
11106 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11107 | if (ctx->task == TASK_TOMBSTONE) { |
11108 | err = -ESRCH; | |
11109 | goto err_unlock; | |
11110 | } | |
11111 | ||
a63fbed7 TG |
11112 | if (!task) { |
11113 | /* | |
11114 | * Check if the @cpu we're creating an event for is online. | |
11115 | * | |
11116 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11117 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11118 | */ | |
11119 | struct perf_cpu_context *cpuctx = | |
11120 | container_of(ctx, struct perf_cpu_context, ctx); | |
11121 | if (!cpuctx->online) { | |
11122 | err = -ENODEV; | |
11123 | goto err_unlock; | |
11124 | } | |
11125 | } | |
11126 | ||
bed5b25a | 11127 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11128 | err = -EBUSY; |
84c4e620 | 11129 | goto err_unlock; |
bed5b25a AS |
11130 | } |
11131 | ||
fb0459d7 | 11132 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 11133 | perf_unpin_context(ctx); |
fb0459d7 AV |
11134 | mutex_unlock(&ctx->mutex); |
11135 | ||
fb0459d7 AV |
11136 | return event; |
11137 | ||
84c4e620 PZ |
11138 | err_unlock: |
11139 | mutex_unlock(&ctx->mutex); | |
11140 | perf_unpin_context(ctx); | |
11141 | put_ctx(ctx); | |
c3f00c70 PZ |
11142 | err_free: |
11143 | free_event(event); | |
11144 | err: | |
c6567f64 | 11145 | return ERR_PTR(err); |
9b51f66d | 11146 | } |
fb0459d7 | 11147 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11148 | |
0cda4c02 YZ |
11149 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11150 | { | |
11151 | struct perf_event_context *src_ctx; | |
11152 | struct perf_event_context *dst_ctx; | |
11153 | struct perf_event *event, *tmp; | |
11154 | LIST_HEAD(events); | |
11155 | ||
11156 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11157 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11158 | ||
f63a8daa PZ |
11159 | /* |
11160 | * See perf_event_ctx_lock() for comments on the details | |
11161 | * of swizzling perf_event::ctx. | |
11162 | */ | |
11163 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11164 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11165 | event_entry) { | |
45a0e07a | 11166 | perf_remove_from_context(event, 0); |
9a545de0 | 11167 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11168 | put_ctx(src_ctx); |
9886167d | 11169 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11170 | } |
0cda4c02 | 11171 | |
8f95b435 PZI |
11172 | /* |
11173 | * Wait for the events to quiesce before re-instating them. | |
11174 | */ | |
0cda4c02 YZ |
11175 | synchronize_rcu(); |
11176 | ||
8f95b435 PZI |
11177 | /* |
11178 | * Re-instate events in 2 passes. | |
11179 | * | |
11180 | * Skip over group leaders and only install siblings on this first | |
11181 | * pass, siblings will not get enabled without a leader, however a | |
11182 | * leader will enable its siblings, even if those are still on the old | |
11183 | * context. | |
11184 | */ | |
11185 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11186 | if (event->group_leader == event) | |
11187 | continue; | |
11188 | ||
11189 | list_del(&event->migrate_entry); | |
11190 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11191 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11192 | account_event_cpu(event, dst_cpu); | |
11193 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11194 | get_ctx(dst_ctx); | |
11195 | } | |
11196 | ||
11197 | /* | |
11198 | * Once all the siblings are setup properly, install the group leaders | |
11199 | * to make it go. | |
11200 | */ | |
9886167d PZ |
11201 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11202 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11203 | if (event->state >= PERF_EVENT_STATE_OFF) |
11204 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11205 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11206 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11207 | get_ctx(dst_ctx); | |
11208 | } | |
11209 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11210 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11211 | } |
11212 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11213 | ||
cdd6c482 | 11214 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11215 | struct task_struct *child) |
d859e29f | 11216 | { |
cdd6c482 | 11217 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11218 | u64 child_val; |
d859e29f | 11219 | |
cdd6c482 IM |
11220 | if (child_event->attr.inherit_stat) |
11221 | perf_event_read_event(child_event, child); | |
38b200d6 | 11222 | |
b5e58793 | 11223 | child_val = perf_event_count(child_event); |
d859e29f PM |
11224 | |
11225 | /* | |
11226 | * Add back the child's count to the parent's count: | |
11227 | */ | |
a6e6dea6 | 11228 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11229 | atomic64_add(child_event->total_time_enabled, |
11230 | &parent_event->child_total_time_enabled); | |
11231 | atomic64_add(child_event->total_time_running, | |
11232 | &parent_event->child_total_time_running); | |
d859e29f PM |
11233 | } |
11234 | ||
9b51f66d | 11235 | static void |
8ba289b8 PZ |
11236 | perf_event_exit_event(struct perf_event *child_event, |
11237 | struct perf_event_context *child_ctx, | |
11238 | struct task_struct *child) | |
9b51f66d | 11239 | { |
8ba289b8 PZ |
11240 | struct perf_event *parent_event = child_event->parent; |
11241 | ||
1903d50c PZ |
11242 | /* |
11243 | * Do not destroy the 'original' grouping; because of the context | |
11244 | * switch optimization the original events could've ended up in a | |
11245 | * random child task. | |
11246 | * | |
11247 | * If we were to destroy the original group, all group related | |
11248 | * operations would cease to function properly after this random | |
11249 | * child dies. | |
11250 | * | |
11251 | * Do destroy all inherited groups, we don't care about those | |
11252 | * and being thorough is better. | |
11253 | */ | |
32132a3d PZ |
11254 | raw_spin_lock_irq(&child_ctx->lock); |
11255 | WARN_ON_ONCE(child_ctx->is_active); | |
11256 | ||
8ba289b8 | 11257 | if (parent_event) |
32132a3d PZ |
11258 | perf_group_detach(child_event); |
11259 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11260 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11261 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11262 | |
9b51f66d | 11263 | /* |
8ba289b8 | 11264 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11265 | */ |
8ba289b8 | 11266 | if (!parent_event) { |
179033b3 | 11267 | perf_event_wakeup(child_event); |
8ba289b8 | 11268 | return; |
4bcf349a | 11269 | } |
8ba289b8 PZ |
11270 | /* |
11271 | * Child events can be cleaned up. | |
11272 | */ | |
11273 | ||
11274 | sync_child_event(child_event, child); | |
11275 | ||
11276 | /* | |
11277 | * Remove this event from the parent's list | |
11278 | */ | |
11279 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11280 | mutex_lock(&parent_event->child_mutex); | |
11281 | list_del_init(&child_event->child_list); | |
11282 | mutex_unlock(&parent_event->child_mutex); | |
11283 | ||
11284 | /* | |
11285 | * Kick perf_poll() for is_event_hup(). | |
11286 | */ | |
11287 | perf_event_wakeup(parent_event); | |
11288 | free_event(child_event); | |
11289 | put_event(parent_event); | |
9b51f66d IM |
11290 | } |
11291 | ||
8dc85d54 | 11292 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 11293 | { |
211de6eb | 11294 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 11295 | struct perf_event *child_event, *next; |
63b6da39 PZ |
11296 | |
11297 | WARN_ON_ONCE(child != current); | |
9b51f66d | 11298 | |
6a3351b6 | 11299 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 11300 | if (!child_ctx) |
9b51f66d IM |
11301 | return; |
11302 | ||
ad3a37de | 11303 | /* |
6a3351b6 PZ |
11304 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
11305 | * ctx::mutex over the entire thing. This serializes against almost | |
11306 | * everything that wants to access the ctx. | |
11307 | * | |
11308 | * The exception is sys_perf_event_open() / | |
11309 | * perf_event_create_kernel_count() which does find_get_context() | |
11310 | * without ctx::mutex (it cannot because of the move_group double mutex | |
11311 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 11312 | */ |
6a3351b6 | 11313 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
11314 | |
11315 | /* | |
6a3351b6 PZ |
11316 | * In a single ctx::lock section, de-schedule the events and detach the |
11317 | * context from the task such that we cannot ever get it scheduled back | |
11318 | * in. | |
c93f7669 | 11319 | */ |
6a3351b6 | 11320 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 11321 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 11322 | |
71a851b4 | 11323 | /* |
63b6da39 PZ |
11324 | * Now that the context is inactive, destroy the task <-> ctx relation |
11325 | * and mark the context dead. | |
71a851b4 | 11326 | */ |
63b6da39 PZ |
11327 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
11328 | put_ctx(child_ctx); /* cannot be last */ | |
11329 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
11330 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 11331 | |
211de6eb | 11332 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 11333 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 11334 | |
211de6eb PZ |
11335 | if (clone_ctx) |
11336 | put_ctx(clone_ctx); | |
4a1c0f26 | 11337 | |
9f498cc5 | 11338 | /* |
cdd6c482 IM |
11339 | * Report the task dead after unscheduling the events so that we |
11340 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
11341 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 11342 | */ |
cdd6c482 | 11343 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 11344 | |
ebf905fc | 11345 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 11346 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 11347 | |
a63eaf34 PM |
11348 | mutex_unlock(&child_ctx->mutex); |
11349 | ||
11350 | put_ctx(child_ctx); | |
9b51f66d IM |
11351 | } |
11352 | ||
8dc85d54 PZ |
11353 | /* |
11354 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
11355 | * |
11356 | * Can be called with cred_guard_mutex held when called from | |
11357 | * install_exec_creds(). | |
8dc85d54 PZ |
11358 | */ |
11359 | void perf_event_exit_task(struct task_struct *child) | |
11360 | { | |
8882135b | 11361 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
11362 | int ctxn; |
11363 | ||
8882135b PZ |
11364 | mutex_lock(&child->perf_event_mutex); |
11365 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
11366 | owner_entry) { | |
11367 | list_del_init(&event->owner_entry); | |
11368 | ||
11369 | /* | |
11370 | * Ensure the list deletion is visible before we clear | |
11371 | * the owner, closes a race against perf_release() where | |
11372 | * we need to serialize on the owner->perf_event_mutex. | |
11373 | */ | |
f47c02c0 | 11374 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11375 | } |
11376 | mutex_unlock(&child->perf_event_mutex); | |
11377 | ||
8dc85d54 PZ |
11378 | for_each_task_context_nr(ctxn) |
11379 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11380 | |
11381 | /* | |
11382 | * The perf_event_exit_task_context calls perf_event_task | |
11383 | * with child's task_ctx, which generates EXIT events for | |
11384 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11385 | * At this point we need to send EXIT events to cpu contexts. | |
11386 | */ | |
11387 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11388 | } |
11389 | ||
889ff015 FW |
11390 | static void perf_free_event(struct perf_event *event, |
11391 | struct perf_event_context *ctx) | |
11392 | { | |
11393 | struct perf_event *parent = event->parent; | |
11394 | ||
11395 | if (WARN_ON_ONCE(!parent)) | |
11396 | return; | |
11397 | ||
11398 | mutex_lock(&parent->child_mutex); | |
11399 | list_del_init(&event->child_list); | |
11400 | mutex_unlock(&parent->child_mutex); | |
11401 | ||
a6fa941d | 11402 | put_event(parent); |
889ff015 | 11403 | |
652884fe | 11404 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11405 | perf_group_detach(event); |
889ff015 | 11406 | list_del_event(event, ctx); |
652884fe | 11407 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11408 | free_event(event); |
11409 | } | |
11410 | ||
bbbee908 | 11411 | /* |
652884fe | 11412 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 11413 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
11414 | * |
11415 | * Not all locks are strictly required, but take them anyway to be nice and | |
11416 | * help out with the lockdep assertions. | |
bbbee908 | 11417 | */ |
cdd6c482 | 11418 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11419 | { |
8dc85d54 | 11420 | struct perf_event_context *ctx; |
cdd6c482 | 11421 | struct perf_event *event, *tmp; |
8dc85d54 | 11422 | int ctxn; |
bbbee908 | 11423 | |
8dc85d54 PZ |
11424 | for_each_task_context_nr(ctxn) { |
11425 | ctx = task->perf_event_ctxp[ctxn]; | |
11426 | if (!ctx) | |
11427 | continue; | |
bbbee908 | 11428 | |
8dc85d54 | 11429 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11430 | raw_spin_lock_irq(&ctx->lock); |
11431 | /* | |
11432 | * Destroy the task <-> ctx relation and mark the context dead. | |
11433 | * | |
11434 | * This is important because even though the task hasn't been | |
11435 | * exposed yet the context has been (through child_list). | |
11436 | */ | |
11437 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11438 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11439 | put_task_struct(task); /* cannot be last */ | |
11440 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11441 | |
15121c78 | 11442 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11443 | perf_free_event(event, ctx); |
bbbee908 | 11444 | |
8dc85d54 | 11445 | mutex_unlock(&ctx->mutex); |
8dc85d54 PZ |
11446 | put_ctx(ctx); |
11447 | } | |
889ff015 FW |
11448 | } |
11449 | ||
4e231c79 PZ |
11450 | void perf_event_delayed_put(struct task_struct *task) |
11451 | { | |
11452 | int ctxn; | |
11453 | ||
11454 | for_each_task_context_nr(ctxn) | |
11455 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
11456 | } | |
11457 | ||
e03e7ee3 | 11458 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 11459 | { |
e03e7ee3 | 11460 | struct file *file; |
ffe8690c | 11461 | |
e03e7ee3 AS |
11462 | file = fget_raw(fd); |
11463 | if (!file) | |
11464 | return ERR_PTR(-EBADF); | |
ffe8690c | 11465 | |
e03e7ee3 AS |
11466 | if (file->f_op != &perf_fops) { |
11467 | fput(file); | |
11468 | return ERR_PTR(-EBADF); | |
11469 | } | |
ffe8690c | 11470 | |
e03e7ee3 | 11471 | return file; |
ffe8690c KX |
11472 | } |
11473 | ||
f8d959a5 YS |
11474 | const struct perf_event *perf_get_event(struct file *file) |
11475 | { | |
11476 | if (file->f_op != &perf_fops) | |
11477 | return ERR_PTR(-EINVAL); | |
11478 | ||
11479 | return file->private_data; | |
11480 | } | |
11481 | ||
ffe8690c KX |
11482 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
11483 | { | |
11484 | if (!event) | |
11485 | return ERR_PTR(-EINVAL); | |
11486 | ||
11487 | return &event->attr; | |
11488 | } | |
11489 | ||
97dee4f3 | 11490 | /* |
788faab7 | 11491 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
11492 | * |
11493 | * Returns: | |
11494 | * - valid pointer on success | |
11495 | * - NULL for orphaned events | |
11496 | * - IS_ERR() on error | |
97dee4f3 PZ |
11497 | */ |
11498 | static struct perf_event * | |
11499 | inherit_event(struct perf_event *parent_event, | |
11500 | struct task_struct *parent, | |
11501 | struct perf_event_context *parent_ctx, | |
11502 | struct task_struct *child, | |
11503 | struct perf_event *group_leader, | |
11504 | struct perf_event_context *child_ctx) | |
11505 | { | |
8ca2bd41 | 11506 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 11507 | struct perf_event *child_event; |
cee010ec | 11508 | unsigned long flags; |
97dee4f3 PZ |
11509 | |
11510 | /* | |
11511 | * Instead of creating recursive hierarchies of events, | |
11512 | * we link inherited events back to the original parent, | |
11513 | * which has a filp for sure, which we use as the reference | |
11514 | * count: | |
11515 | */ | |
11516 | if (parent_event->parent) | |
11517 | parent_event = parent_event->parent; | |
11518 | ||
11519 | child_event = perf_event_alloc(&parent_event->attr, | |
11520 | parent_event->cpu, | |
d580ff86 | 11521 | child, |
97dee4f3 | 11522 | group_leader, parent_event, |
79dff51e | 11523 | NULL, NULL, -1); |
97dee4f3 PZ |
11524 | if (IS_ERR(child_event)) |
11525 | return child_event; | |
a6fa941d | 11526 | |
313ccb96 JO |
11527 | |
11528 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
11529 | !child_ctx->task_ctx_data) { | |
11530 | struct pmu *pmu = child_event->pmu; | |
11531 | ||
11532 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
11533 | GFP_KERNEL); | |
11534 | if (!child_ctx->task_ctx_data) { | |
11535 | free_event(child_event); | |
11536 | return NULL; | |
11537 | } | |
11538 | } | |
11539 | ||
c6e5b732 PZ |
11540 | /* |
11541 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
11542 | * must be under the same lock in order to serialize against | |
11543 | * perf_event_release_kernel(), such that either we must observe | |
11544 | * is_orphaned_event() or they will observe us on the child_list. | |
11545 | */ | |
11546 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
11547 | if (is_orphaned_event(parent_event) || |
11548 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 11549 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 11550 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
11551 | free_event(child_event); |
11552 | return NULL; | |
11553 | } | |
11554 | ||
97dee4f3 PZ |
11555 | get_ctx(child_ctx); |
11556 | ||
11557 | /* | |
11558 | * Make the child state follow the state of the parent event, | |
11559 | * not its attr.disabled bit. We hold the parent's mutex, | |
11560 | * so we won't race with perf_event_{en, dis}able_family. | |
11561 | */ | |
1929def9 | 11562 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
11563 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
11564 | else | |
11565 | child_event->state = PERF_EVENT_STATE_OFF; | |
11566 | ||
11567 | if (parent_event->attr.freq) { | |
11568 | u64 sample_period = parent_event->hw.sample_period; | |
11569 | struct hw_perf_event *hwc = &child_event->hw; | |
11570 | ||
11571 | hwc->sample_period = sample_period; | |
11572 | hwc->last_period = sample_period; | |
11573 | ||
11574 | local64_set(&hwc->period_left, sample_period); | |
11575 | } | |
11576 | ||
11577 | child_event->ctx = child_ctx; | |
11578 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
11579 | child_event->overflow_handler_context |
11580 | = parent_event->overflow_handler_context; | |
97dee4f3 | 11581 | |
614b6780 TG |
11582 | /* |
11583 | * Precalculate sample_data sizes | |
11584 | */ | |
11585 | perf_event__header_size(child_event); | |
6844c09d | 11586 | perf_event__id_header_size(child_event); |
614b6780 | 11587 | |
97dee4f3 PZ |
11588 | /* |
11589 | * Link it up in the child's context: | |
11590 | */ | |
cee010ec | 11591 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 11592 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 11593 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 11594 | |
97dee4f3 PZ |
11595 | /* |
11596 | * Link this into the parent event's child list | |
11597 | */ | |
97dee4f3 PZ |
11598 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
11599 | mutex_unlock(&parent_event->child_mutex); | |
11600 | ||
11601 | return child_event; | |
11602 | } | |
11603 | ||
d8a8cfc7 PZ |
11604 | /* |
11605 | * Inherits an event group. | |
11606 | * | |
11607 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
11608 | * This matches with perf_event_release_kernel() removing all child events. | |
11609 | * | |
11610 | * Returns: | |
11611 | * - 0 on success | |
11612 | * - <0 on error | |
11613 | */ | |
97dee4f3 PZ |
11614 | static int inherit_group(struct perf_event *parent_event, |
11615 | struct task_struct *parent, | |
11616 | struct perf_event_context *parent_ctx, | |
11617 | struct task_struct *child, | |
11618 | struct perf_event_context *child_ctx) | |
11619 | { | |
11620 | struct perf_event *leader; | |
11621 | struct perf_event *sub; | |
11622 | struct perf_event *child_ctr; | |
11623 | ||
11624 | leader = inherit_event(parent_event, parent, parent_ctx, | |
11625 | child, NULL, child_ctx); | |
11626 | if (IS_ERR(leader)) | |
11627 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
11628 | /* |
11629 | * @leader can be NULL here because of is_orphaned_event(). In this | |
11630 | * case inherit_event() will create individual events, similar to what | |
11631 | * perf_group_detach() would do anyway. | |
11632 | */ | |
edb39592 | 11633 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
11634 | child_ctr = inherit_event(sub, parent, parent_ctx, |
11635 | child, leader, child_ctx); | |
11636 | if (IS_ERR(child_ctr)) | |
11637 | return PTR_ERR(child_ctr); | |
11638 | } | |
11639 | return 0; | |
889ff015 FW |
11640 | } |
11641 | ||
d8a8cfc7 PZ |
11642 | /* |
11643 | * Creates the child task context and tries to inherit the event-group. | |
11644 | * | |
11645 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
11646 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
11647 | * consistent with perf_event_release_kernel() removing all child events. | |
11648 | * | |
11649 | * Returns: | |
11650 | * - 0 on success | |
11651 | * - <0 on error | |
11652 | */ | |
889ff015 FW |
11653 | static int |
11654 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
11655 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 11656 | struct task_struct *child, int ctxn, |
889ff015 FW |
11657 | int *inherited_all) |
11658 | { | |
11659 | int ret; | |
8dc85d54 | 11660 | struct perf_event_context *child_ctx; |
889ff015 FW |
11661 | |
11662 | if (!event->attr.inherit) { | |
11663 | *inherited_all = 0; | |
11664 | return 0; | |
bbbee908 PZ |
11665 | } |
11666 | ||
fe4b04fa | 11667 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
11668 | if (!child_ctx) { |
11669 | /* | |
11670 | * This is executed from the parent task context, so | |
11671 | * inherit events that have been marked for cloning. | |
11672 | * First allocate and initialize a context for the | |
11673 | * child. | |
11674 | */ | |
734df5ab | 11675 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
11676 | if (!child_ctx) |
11677 | return -ENOMEM; | |
bbbee908 | 11678 | |
8dc85d54 | 11679 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
11680 | } |
11681 | ||
11682 | ret = inherit_group(event, parent, parent_ctx, | |
11683 | child, child_ctx); | |
11684 | ||
11685 | if (ret) | |
11686 | *inherited_all = 0; | |
11687 | ||
11688 | return ret; | |
bbbee908 PZ |
11689 | } |
11690 | ||
9b51f66d | 11691 | /* |
cdd6c482 | 11692 | * Initialize the perf_event context in task_struct |
9b51f66d | 11693 | */ |
985c8dcb | 11694 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 11695 | { |
889ff015 | 11696 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
11697 | struct perf_event_context *cloned_ctx; |
11698 | struct perf_event *event; | |
9b51f66d | 11699 | struct task_struct *parent = current; |
564c2b21 | 11700 | int inherited_all = 1; |
dddd3379 | 11701 | unsigned long flags; |
6ab423e0 | 11702 | int ret = 0; |
9b51f66d | 11703 | |
8dc85d54 | 11704 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
11705 | return 0; |
11706 | ||
ad3a37de | 11707 | /* |
25346b93 PM |
11708 | * If the parent's context is a clone, pin it so it won't get |
11709 | * swapped under us. | |
ad3a37de | 11710 | */ |
8dc85d54 | 11711 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
11712 | if (!parent_ctx) |
11713 | return 0; | |
25346b93 | 11714 | |
ad3a37de PM |
11715 | /* |
11716 | * No need to check if parent_ctx != NULL here; since we saw | |
11717 | * it non-NULL earlier, the only reason for it to become NULL | |
11718 | * is if we exit, and since we're currently in the middle of | |
11719 | * a fork we can't be exiting at the same time. | |
11720 | */ | |
ad3a37de | 11721 | |
9b51f66d IM |
11722 | /* |
11723 | * Lock the parent list. No need to lock the child - not PID | |
11724 | * hashed yet and not running, so nobody can access it. | |
11725 | */ | |
d859e29f | 11726 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
11727 | |
11728 | /* | |
11729 | * We dont have to disable NMIs - we are only looking at | |
11730 | * the list, not manipulating it: | |
11731 | */ | |
6e6804d2 | 11732 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
11733 | ret = inherit_task_group(event, parent, parent_ctx, |
11734 | child, ctxn, &inherited_all); | |
889ff015 | 11735 | if (ret) |
e7cc4865 | 11736 | goto out_unlock; |
889ff015 | 11737 | } |
b93f7978 | 11738 | |
dddd3379 TG |
11739 | /* |
11740 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
11741 | * to allocations, but we need to prevent rotation because | |
11742 | * rotate_ctx() will change the list from interrupt context. | |
11743 | */ | |
11744 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
11745 | parent_ctx->rotate_disable = 1; | |
11746 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
11747 | ||
6e6804d2 | 11748 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
11749 | ret = inherit_task_group(event, parent, parent_ctx, |
11750 | child, ctxn, &inherited_all); | |
889ff015 | 11751 | if (ret) |
e7cc4865 | 11752 | goto out_unlock; |
564c2b21 PM |
11753 | } |
11754 | ||
dddd3379 TG |
11755 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
11756 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 11757 | |
8dc85d54 | 11758 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 11759 | |
05cbaa28 | 11760 | if (child_ctx && inherited_all) { |
564c2b21 PM |
11761 | /* |
11762 | * Mark the child context as a clone of the parent | |
11763 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
11764 | * |
11765 | * Note that if the parent is a clone, the holding of | |
11766 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 11767 | */ |
c5ed5145 | 11768 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
11769 | if (cloned_ctx) { |
11770 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 11771 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
11772 | } else { |
11773 | child_ctx->parent_ctx = parent_ctx; | |
11774 | child_ctx->parent_gen = parent_ctx->generation; | |
11775 | } | |
11776 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
11777 | } |
11778 | ||
c5ed5145 | 11779 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 11780 | out_unlock: |
d859e29f | 11781 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 11782 | |
25346b93 | 11783 | perf_unpin_context(parent_ctx); |
fe4b04fa | 11784 | put_ctx(parent_ctx); |
ad3a37de | 11785 | |
6ab423e0 | 11786 | return ret; |
9b51f66d IM |
11787 | } |
11788 | ||
8dc85d54 PZ |
11789 | /* |
11790 | * Initialize the perf_event context in task_struct | |
11791 | */ | |
11792 | int perf_event_init_task(struct task_struct *child) | |
11793 | { | |
11794 | int ctxn, ret; | |
11795 | ||
8550d7cb ON |
11796 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
11797 | mutex_init(&child->perf_event_mutex); | |
11798 | INIT_LIST_HEAD(&child->perf_event_list); | |
11799 | ||
8dc85d54 PZ |
11800 | for_each_task_context_nr(ctxn) { |
11801 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
11802 | if (ret) { |
11803 | perf_event_free_task(child); | |
8dc85d54 | 11804 | return ret; |
6c72e350 | 11805 | } |
8dc85d54 PZ |
11806 | } |
11807 | ||
11808 | return 0; | |
11809 | } | |
11810 | ||
220b140b PM |
11811 | static void __init perf_event_init_all_cpus(void) |
11812 | { | |
b28ab83c | 11813 | struct swevent_htable *swhash; |
220b140b | 11814 | int cpu; |
220b140b | 11815 | |
a63fbed7 TG |
11816 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
11817 | ||
220b140b | 11818 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
11819 | swhash = &per_cpu(swevent_htable, cpu); |
11820 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 11821 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
11822 | |
11823 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
11824 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 11825 | |
058fe1c0 DCC |
11826 | #ifdef CONFIG_CGROUP_PERF |
11827 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
11828 | #endif | |
e48c1788 | 11829 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
11830 | } |
11831 | } | |
11832 | ||
a63fbed7 | 11833 | void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 11834 | { |
108b02cf | 11835 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 11836 | |
b28ab83c | 11837 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 11838 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
11839 | struct swevent_hlist *hlist; |
11840 | ||
b28ab83c PZ |
11841 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
11842 | WARN_ON(!hlist); | |
11843 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 11844 | } |
b28ab83c | 11845 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
11846 | } |
11847 | ||
2965faa5 | 11848 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 11849 | static void __perf_event_exit_context(void *__info) |
0793a61d | 11850 | { |
108b02cf | 11851 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
11852 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
11853 | struct perf_event *event; | |
0793a61d | 11854 | |
fae3fde6 | 11855 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 11856 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 11857 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 11858 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 11859 | raw_spin_unlock(&ctx->lock); |
0793a61d | 11860 | } |
108b02cf PZ |
11861 | |
11862 | static void perf_event_exit_cpu_context(int cpu) | |
11863 | { | |
a63fbed7 | 11864 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
11865 | struct perf_event_context *ctx; |
11866 | struct pmu *pmu; | |
108b02cf | 11867 | |
a63fbed7 TG |
11868 | mutex_lock(&pmus_lock); |
11869 | list_for_each_entry(pmu, &pmus, entry) { | |
11870 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11871 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
11872 | |
11873 | mutex_lock(&ctx->mutex); | |
11874 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 11875 | cpuctx->online = 0; |
108b02cf PZ |
11876 | mutex_unlock(&ctx->mutex); |
11877 | } | |
a63fbed7 TG |
11878 | cpumask_clear_cpu(cpu, perf_online_mask); |
11879 | mutex_unlock(&pmus_lock); | |
108b02cf | 11880 | } |
00e16c3d TG |
11881 | #else |
11882 | ||
11883 | static void perf_event_exit_cpu_context(int cpu) { } | |
11884 | ||
11885 | #endif | |
108b02cf | 11886 | |
a63fbed7 TG |
11887 | int perf_event_init_cpu(unsigned int cpu) |
11888 | { | |
11889 | struct perf_cpu_context *cpuctx; | |
11890 | struct perf_event_context *ctx; | |
11891 | struct pmu *pmu; | |
11892 | ||
11893 | perf_swevent_init_cpu(cpu); | |
11894 | ||
11895 | mutex_lock(&pmus_lock); | |
11896 | cpumask_set_cpu(cpu, perf_online_mask); | |
11897 | list_for_each_entry(pmu, &pmus, entry) { | |
11898 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11899 | ctx = &cpuctx->ctx; | |
11900 | ||
11901 | mutex_lock(&ctx->mutex); | |
11902 | cpuctx->online = 1; | |
11903 | mutex_unlock(&ctx->mutex); | |
11904 | } | |
11905 | mutex_unlock(&pmus_lock); | |
11906 | ||
11907 | return 0; | |
11908 | } | |
11909 | ||
00e16c3d | 11910 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 11911 | { |
e3703f8c | 11912 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 11913 | return 0; |
0793a61d | 11914 | } |
0793a61d | 11915 | |
c277443c PZ |
11916 | static int |
11917 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
11918 | { | |
11919 | int cpu; | |
11920 | ||
11921 | for_each_online_cpu(cpu) | |
11922 | perf_event_exit_cpu(cpu); | |
11923 | ||
11924 | return NOTIFY_OK; | |
11925 | } | |
11926 | ||
11927 | /* | |
11928 | * Run the perf reboot notifier at the very last possible moment so that | |
11929 | * the generic watchdog code runs as long as possible. | |
11930 | */ | |
11931 | static struct notifier_block perf_reboot_notifier = { | |
11932 | .notifier_call = perf_reboot, | |
11933 | .priority = INT_MIN, | |
11934 | }; | |
11935 | ||
cdd6c482 | 11936 | void __init perf_event_init(void) |
0793a61d | 11937 | { |
3c502e7a JW |
11938 | int ret; |
11939 | ||
2e80a82a PZ |
11940 | idr_init(&pmu_idr); |
11941 | ||
220b140b | 11942 | perf_event_init_all_cpus(); |
b0a873eb | 11943 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
11944 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
11945 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
11946 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 11947 | perf_tp_register(); |
00e16c3d | 11948 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 11949 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
11950 | |
11951 | ret = init_hw_breakpoint(); | |
11952 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 11953 | |
b01c3a00 JO |
11954 | /* |
11955 | * Build time assertion that we keep the data_head at the intended | |
11956 | * location. IOW, validation we got the __reserved[] size right. | |
11957 | */ | |
11958 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
11959 | != 1024); | |
0793a61d | 11960 | } |
abe43400 | 11961 | |
fd979c01 CS |
11962 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
11963 | char *page) | |
11964 | { | |
11965 | struct perf_pmu_events_attr *pmu_attr = | |
11966 | container_of(attr, struct perf_pmu_events_attr, attr); | |
11967 | ||
11968 | if (pmu_attr->event_str) | |
11969 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
11970 | ||
11971 | return 0; | |
11972 | } | |
675965b0 | 11973 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 11974 | |
abe43400 PZ |
11975 | static int __init perf_event_sysfs_init(void) |
11976 | { | |
11977 | struct pmu *pmu; | |
11978 | int ret; | |
11979 | ||
11980 | mutex_lock(&pmus_lock); | |
11981 | ||
11982 | ret = bus_register(&pmu_bus); | |
11983 | if (ret) | |
11984 | goto unlock; | |
11985 | ||
11986 | list_for_each_entry(pmu, &pmus, entry) { | |
11987 | if (!pmu->name || pmu->type < 0) | |
11988 | continue; | |
11989 | ||
11990 | ret = pmu_dev_alloc(pmu); | |
11991 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
11992 | } | |
11993 | pmu_bus_running = 1; | |
11994 | ret = 0; | |
11995 | ||
11996 | unlock: | |
11997 | mutex_unlock(&pmus_lock); | |
11998 | ||
11999 | return ret; | |
12000 | } | |
12001 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12002 | |
12003 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12004 | static struct cgroup_subsys_state * |
12005 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12006 | { |
12007 | struct perf_cgroup *jc; | |
e5d1367f | 12008 | |
1b15d055 | 12009 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12010 | if (!jc) |
12011 | return ERR_PTR(-ENOMEM); | |
12012 | ||
e5d1367f SE |
12013 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12014 | if (!jc->info) { | |
12015 | kfree(jc); | |
12016 | return ERR_PTR(-ENOMEM); | |
12017 | } | |
12018 | ||
e5d1367f SE |
12019 | return &jc->css; |
12020 | } | |
12021 | ||
eb95419b | 12022 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12023 | { |
eb95419b TH |
12024 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12025 | ||
e5d1367f SE |
12026 | free_percpu(jc->info); |
12027 | kfree(jc); | |
12028 | } | |
12029 | ||
12030 | static int __perf_cgroup_move(void *info) | |
12031 | { | |
12032 | struct task_struct *task = info; | |
ddaaf4e2 | 12033 | rcu_read_lock(); |
e5d1367f | 12034 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12035 | rcu_read_unlock(); |
e5d1367f SE |
12036 | return 0; |
12037 | } | |
12038 | ||
1f7dd3e5 | 12039 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12040 | { |
bb9d97b6 | 12041 | struct task_struct *task; |
1f7dd3e5 | 12042 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12043 | |
1f7dd3e5 | 12044 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12045 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12046 | } |
12047 | ||
073219e9 | 12048 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12049 | .css_alloc = perf_cgroup_css_alloc, |
12050 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12051 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12052 | /* |
12053 | * Implicitly enable on dfl hierarchy so that perf events can | |
12054 | * always be filtered by cgroup2 path as long as perf_event | |
12055 | * controller is not mounted on a legacy hierarchy. | |
12056 | */ | |
12057 | .implicit_on_dfl = true, | |
8cfd8147 | 12058 | .threaded = true, |
e5d1367f SE |
12059 | }; |
12060 | #endif /* CONFIG_CGROUP_PERF */ |