1 /*
2 * Performance events:
3 *
4 * Copyright (C) 2008-2009, Thomas Gleixner <tglx@linutronix.de>
5 * Copyright (C) 2008-2011, Red Hat, Inc., Ingo Molnar
6 * Copyright (C) 2008-2011, Red Hat, Inc., Peter Zijlstra
7 *
8 * Data type definitions, declarations, prototypes.
9 *
10 * Started by: Thomas Gleixner and Ingo Molnar
11 *
12 * For licencing details see kernel-base/COPYING
13 */
14 #ifndef _LINUX_PERF_EVENT_H
15 #define _LINUX_PERF_EVENT_H
16
17 #include <uapi/linux/perf_event.h>
18 #include <uapi/linux/bpf_perf_event.h>
19
20 /*
21 * Kernel-internal data types and definitions:
22 */
23
24 #ifdef CONFIG_PERF_EVENTS
25 # include <asm/perf_event.h>
26 # include <asm/local64.h>
27 #endif
28
29 #define PERF_GUEST_ACTIVE 0x01
30 #define PERF_GUEST_USER 0x02
31
32 struct perf_guest_info_callbacks {
33 unsigned int (*state)(void);
34 unsigned long (*get_ip)(void);
35 unsigned int (*handle_intel_pt_intr)(void);
36 };
37
38 #ifdef CONFIG_HAVE_HW_BREAKPOINT
39 #include <linux/rhashtable-types.h>
40 #include <asm/hw_breakpoint.h>
41 #endif
42
43 #include <linux/list.h>
44 #include <linux/mutex.h>
45 #include <linux/rculist.h>
46 #include <linux/rcupdate.h>
47 #include <linux/spinlock.h>
48 #include <linux/hrtimer.h>
49 #include <linux/fs.h>
50 #include <linux/pid_namespace.h>
51 #include <linux/workqueue.h>
52 #include <linux/ftrace.h>
53 #include <linux/cpu.h>
54 #include <linux/irq_work.h>
55 #include <linux/static_key.h>
56 #include <linux/jump_label_ratelimit.h>
57 #include <linux/atomic.h>
58 #include <linux/sysfs.h>
59 #include <linux/perf_regs.h>
60 #include <linux/cgroup.h>
61 #include <linux/refcount.h>
62 #include <linux/security.h>
63 #include <linux/static_call.h>
64 #include <linux/lockdep.h>
65 #include <asm/local.h>
66
67 struct perf_callchain_entry {
68 __u64 nr;
69 __u64 ip[]; /* /proc/sys/kernel/perf_event_max_stack */
70 };
71
72 struct perf_callchain_entry_ctx {
73 struct perf_callchain_entry *entry;
74 u32 max_stack;
75 u32 nr;
76 short contexts;
77 bool contexts_maxed;
78 };
79
80 typedef unsigned long (*perf_copy_f)(void *dst, const void *src,
81 unsigned long off, unsigned long len);
82
83 struct perf_raw_frag {
84 union {
85 struct perf_raw_frag *next;
86 unsigned long pad;
87 };
88 perf_copy_f copy;
89 void *data;
90 u32 size;
91 } __packed;
92
93 struct perf_raw_record {
94 struct perf_raw_frag frag;
95 u32 size;
96 };
97
perf_raw_frag_last(const struct perf_raw_frag * frag)98 static __always_inline bool perf_raw_frag_last(const struct perf_raw_frag *frag)
99 {
100 return frag->pad < sizeof(u64);
101 }
102
103 /*
104 * branch stack layout:
105 * nr: number of taken branches stored in entries[]
106 * hw_idx: The low level index of raw branch records
107 * for the most recent branch.
108 * -1ULL means invalid/unknown.
109 *
110 * Note that nr can vary from sample to sample
111 * branches (to, from) are stored from most recent
112 * to least recent, i.e., entries[0] contains the most
113 * recent branch.
114 * The entries[] is an abstraction of raw branch records,
115 * which may not be stored in age order in HW, e.g. Intel LBR.
116 * The hw_idx is to expose the low level index of raw
117 * branch record for the most recent branch aka entries[0].
118 * The hw_idx index is between -1 (unknown) and max depth,
119 * which can be retrieved in /sys/devices/cpu/caps/branches.
120 * For the architectures whose raw branch records are
121 * already stored in age order, the hw_idx should be 0.
122 */
123 struct perf_branch_stack {
124 __u64 nr;
125 __u64 hw_idx;
126 struct perf_branch_entry entries[];
127 };
128
129 struct task_struct;
130
131 /*
132 * extra PMU register associated with an event
133 */
134 struct hw_perf_event_extra {
135 u64 config; /* register value */
136 unsigned int reg; /* register address or index */
137 int alloc; /* extra register already allocated */
138 int idx; /* index in shared_regs->regs[] */
139 };
140
141 /**
142 * hw_perf_event::flag values
143 *
144 * PERF_EVENT_FLAG_ARCH bits are reserved for architecture-specific
145 * usage.
146 */
147 #define PERF_EVENT_FLAG_ARCH 0x000fffff
148 #define PERF_EVENT_FLAG_USER_READ_CNT 0x80000000
149
150 static_assert((PERF_EVENT_FLAG_USER_READ_CNT & PERF_EVENT_FLAG_ARCH) == 0);
151
152 /**
153 * struct hw_perf_event - performance event hardware details:
154 */
155 struct hw_perf_event {
156 #ifdef CONFIG_PERF_EVENTS
157 union {
158 struct { /* hardware */
159 u64 config;
160 u64 last_tag;
161 unsigned long config_base;
162 unsigned long event_base;
163 int event_base_rdpmc;
164 int idx;
165 int last_cpu;
166 int flags;
167
168 struct hw_perf_event_extra extra_reg;
169 struct hw_perf_event_extra branch_reg;
170 };
171 struct { /* software */
172 struct hrtimer hrtimer;
173 };
174 struct { /* tracepoint */
175 /* for tp_event->class */
176 struct list_head tp_list;
177 };
178 struct { /* amd_power */
179 u64 pwr_acc;
180 u64 ptsc;
181 };
182 #ifdef CONFIG_HAVE_HW_BREAKPOINT
183 struct { /* breakpoint */
184 /*
185 * Crufty hack to avoid the chicken and egg
186 * problem hw_breakpoint has with context
187 * creation and event initalization.
188 */
189 struct arch_hw_breakpoint info;
190 struct rhlist_head bp_list;
191 };
192 #endif
193 struct { /* amd_iommu */
194 u8 iommu_bank;
195 u8 iommu_cntr;
196 u16 padding;
197 u64 conf;
198 u64 conf1;
199 };
200 };
201 /*
202 * If the event is a per task event, this will point to the task in
203 * question. See the comment in perf_event_alloc().
204 */
205 struct task_struct *target;
206
207 /*
208 * PMU would store hardware filter configuration
209 * here.
210 */
211 void *addr_filters;
212
213 /* Last sync'ed generation of filters */
214 unsigned long addr_filters_gen;
215
216 /*
217 * hw_perf_event::state flags; used to track the PERF_EF_* state.
218 */
219 #define PERF_HES_STOPPED 0x01 /* the counter is stopped */
220 #define PERF_HES_UPTODATE 0x02 /* event->count up-to-date */
221 #define PERF_HES_ARCH 0x04
222
223 int state;
224
225 /*
226 * The last observed hardware counter value, updated with a
227 * local64_cmpxchg() such that pmu::read() can be called nested.
228 */
229 local64_t prev_count;
230
231 /*
232 * The period to start the next sample with.
233 */
234 u64 sample_period;
235
236 union {
237 struct { /* Sampling */
238 /*
239 * The period we started this sample with.
240 */
241 u64 last_period;
242
243 /*
244 * However much is left of the current period;
245 * note that this is a full 64bit value and
246 * allows for generation of periods longer
247 * than hardware might allow.
248 */
249 local64_t period_left;
250 };
251 struct { /* Topdown events counting for context switch */
252 u64 saved_metric;
253 u64 saved_slots;
254 };
255 };
256
257 /*
258 * State for throttling the event, see __perf_event_overflow() and
259 * perf_adjust_freq_unthr_context().
260 */
261 u64 interrupts_seq;
262 u64 interrupts;
263
264 /*
265 * State for freq target events, see __perf_event_overflow() and
266 * perf_adjust_freq_unthr_context().
267 */
268 u64 freq_time_stamp;
269 u64 freq_count_stamp;
270 #endif
271 };
272
273 struct perf_event;
274 struct perf_event_pmu_context;
275
276 /*
277 * Common implementation detail of pmu::{start,commit,cancel}_txn
278 */
279 #define PERF_PMU_TXN_ADD 0x1 /* txn to add/schedule event on PMU */
280 #define PERF_PMU_TXN_READ 0x2 /* txn to read event group from PMU */
281
282 /**
283 * pmu::capabilities flags
284 */
285 #define PERF_PMU_CAP_NO_INTERRUPT 0x0001
286 #define PERF_PMU_CAP_NO_NMI 0x0002
287 #define PERF_PMU_CAP_AUX_NO_SG 0x0004
288 #define PERF_PMU_CAP_EXTENDED_REGS 0x0008
289 #define PERF_PMU_CAP_EXCLUSIVE 0x0010
290 #define PERF_PMU_CAP_ITRACE 0x0020
291 #define PERF_PMU_CAP_NO_EXCLUDE 0x0040
292 #define PERF_PMU_CAP_AUX_OUTPUT 0x0080
293 #define PERF_PMU_CAP_EXTENDED_HW_TYPE 0x0100
294
295 struct perf_output_handle;
296
297 #define PMU_NULL_DEV ((void *)(~0UL))
298
299 /**
300 * struct pmu - generic performance monitoring unit
301 */
302 struct pmu {
303 struct list_head entry;
304
305 struct module *module;
306 struct device *dev;
307 struct device *parent;
308 const struct attribute_group **attr_groups;
309 const struct attribute_group **attr_update;
310 const char *name;
311 int type;
312
313 /*
314 * various common per-pmu feature flags
315 */
316 int capabilities;
317
318 int __percpu *pmu_disable_count;
319 struct perf_cpu_pmu_context __percpu *cpu_pmu_context;
320 atomic_t exclusive_cnt; /* < 0: cpu; > 0: tsk */
321 int task_ctx_nr;
322 int hrtimer_interval_ms;
323
324 /* number of address filters this PMU can do */
325 unsigned int nr_addr_filters;
326
327 /*
328 * Fully disable/enable this PMU, can be used to protect from the PMI
329 * as well as for lazy/batch writing of the MSRs.
330 */
331 void (*pmu_enable) (struct pmu *pmu); /* optional */
332 void (*pmu_disable) (struct pmu *pmu); /* optional */
333
334 /*
335 * Try and initialize the event for this PMU.
336 *
337 * Returns:
338 * -ENOENT -- @event is not for this PMU
339 *
340 * -ENODEV -- @event is for this PMU but PMU not present
341 * -EBUSY -- @event is for this PMU but PMU temporarily unavailable
342 * -EINVAL -- @event is for this PMU but @event is not valid
343 * -EOPNOTSUPP -- @event is for this PMU, @event is valid, but not supported
344 * -EACCES -- @event is for this PMU, @event is valid, but no privileges
345 *
346 * 0 -- @event is for this PMU and valid
347 *
348 * Other error return values are allowed.
349 */
350 int (*event_init) (struct perf_event *event);
351
352 /*
353 * Notification that the event was mapped or unmapped. Called
354 * in the context of the mapping task.
355 */
356 void (*event_mapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
357 void (*event_unmapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
358
359 /*
360 * Flags for ->add()/->del()/ ->start()/->stop(). There are
361 * matching hw_perf_event::state flags.
362 */
363 #define PERF_EF_START 0x01 /* start the counter when adding */
364 #define PERF_EF_RELOAD 0x02 /* reload the counter when starting */
365 #define PERF_EF_UPDATE 0x04 /* update the counter when stopping */
366
367 /*
368 * Adds/Removes a counter to/from the PMU, can be done inside a
369 * transaction, see the ->*_txn() methods.
370 *
371 * The add/del callbacks will reserve all hardware resources required
372 * to service the event, this includes any counter constraint
373 * scheduling etc.
374 *
375 * Called with IRQs disabled and the PMU disabled on the CPU the event
376 * is on.
377 *
378 * ->add() called without PERF_EF_START should result in the same state
379 * as ->add() followed by ->stop().
380 *
381 * ->del() must always PERF_EF_UPDATE stop an event. If it calls
382 * ->stop() that must deal with already being stopped without
383 * PERF_EF_UPDATE.
384 */
385 int (*add) (struct perf_event *event, int flags);
386 void (*del) (struct perf_event *event, int flags);
387
388 /*
389 * Starts/Stops a counter present on the PMU.
390 *
391 * The PMI handler should stop the counter when perf_event_overflow()
392 * returns !0. ->start() will be used to continue.
393 *
394 * Also used to change the sample period.
395 *
396 * Called with IRQs disabled and the PMU disabled on the CPU the event
397 * is on -- will be called from NMI context with the PMU generates
398 * NMIs.
399 *
400 * ->stop() with PERF_EF_UPDATE will read the counter and update
401 * period/count values like ->read() would.
402 *
403 * ->start() with PERF_EF_RELOAD will reprogram the counter
404 * value, must be preceded by a ->stop() with PERF_EF_UPDATE.
405 */
406 void (*start) (struct perf_event *event, int flags);
407 void (*stop) (struct perf_event *event, int flags);
408
409 /*
410 * Updates the counter value of the event.
411 *
412 * For sampling capable PMUs this will also update the software period
413 * hw_perf_event::period_left field.
414 */
415 void (*read) (struct perf_event *event);
416
417 /*
418 * Group events scheduling is treated as a transaction, add
419 * group events as a whole and perform one schedulability test.
420 * If the test fails, roll back the whole group
421 *
422 * Start the transaction, after this ->add() doesn't need to
423 * do schedulability tests.
424 *
425 * Optional.
426 */
427 void (*start_txn) (struct pmu *pmu, unsigned int txn_flags);
428 /*
429 * If ->start_txn() disabled the ->add() schedulability test
430 * then ->commit_txn() is required to perform one. On success
431 * the transaction is closed. On error the transaction is kept
432 * open until ->cancel_txn() is called.
433 *
434 * Optional.
435 */
436 int (*commit_txn) (struct pmu *pmu);
437 /*
438 * Will cancel the transaction, assumes ->del() is called
439 * for each successful ->add() during the transaction.
440 *
441 * Optional.
442 */
443 void (*cancel_txn) (struct pmu *pmu);
444
445 /*
446 * Will return the value for perf_event_mmap_page::index for this event,
447 * if no implementation is provided it will default to 0 (see
448 * perf_event_idx_default).
449 */
450 int (*event_idx) (struct perf_event *event); /*optional */
451
452 /*
453 * context-switches callback
454 */
455 void (*sched_task) (struct perf_event_pmu_context *pmu_ctx,
456 bool sched_in);
457
458 /*
459 * Kmem cache of PMU specific data
460 */
461 struct kmem_cache *task_ctx_cache;
462
463 /*
464 * PMU specific parts of task perf event context (i.e. ctx->task_ctx_data)
465 * can be synchronized using this function. See Intel LBR callstack support
466 * implementation and Perf core context switch handling callbacks for usage
467 * examples.
468 */
469 void (*swap_task_ctx) (struct perf_event_pmu_context *prev_epc,
470 struct perf_event_pmu_context *next_epc);
471 /* optional */
472
473 /*
474 * Set up pmu-private data structures for an AUX area
475 */
476 void *(*setup_aux) (struct perf_event *event, void **pages,
477 int nr_pages, bool overwrite);
478 /* optional */
479
480 /*
481 * Free pmu-private AUX data structures
482 */
483 void (*free_aux) (void *aux); /* optional */
484
485 /*
486 * Take a snapshot of the AUX buffer without touching the event
487 * state, so that preempting ->start()/->stop() callbacks does
488 * not interfere with their logic. Called in PMI context.
489 *
490 * Returns the size of AUX data copied to the output handle.
491 *
492 * Optional.
493 */
494 long (*snapshot_aux) (struct perf_event *event,
495 struct perf_output_handle *handle,
496 unsigned long size);
497
498 /*
499 * Validate address range filters: make sure the HW supports the
500 * requested configuration and number of filters; return 0 if the
501 * supplied filters are valid, -errno otherwise.
502 *
503 * Runs in the context of the ioctl()ing process and is not serialized
504 * with the rest of the PMU callbacks.
505 */
506 int (*addr_filters_validate) (struct list_head *filters);
507 /* optional */
508
509 /*
510 * Synchronize address range filter configuration:
511 * translate hw-agnostic filters into hardware configuration in
512 * event::hw::addr_filters.
513 *
514 * Runs as a part of filter sync sequence that is done in ->start()
515 * callback by calling perf_event_addr_filters_sync().
516 *
517 * May (and should) traverse event::addr_filters::list, for which its
518 * caller provides necessary serialization.
519 */
520 void (*addr_filters_sync) (struct perf_event *event);
521 /* optional */
522
523 /*
524 * Check if event can be used for aux_output purposes for
525 * events of this PMU.
526 *
527 * Runs from perf_event_open(). Should return 0 for "no match"
528 * or non-zero for "match".
529 */
530 int (*aux_output_match) (struct perf_event *event);
531 /* optional */
532
533 /*
534 * Skip programming this PMU on the given CPU. Typically needed for
535 * big.LITTLE things.
536 */
537 bool (*filter) (struct pmu *pmu, int cpu); /* optional */
538
539 /*
540 * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
541 */
542 int (*check_period) (struct perf_event *event, u64 value); /* optional */
543 };
544
545 enum perf_addr_filter_action_t {
546 PERF_ADDR_FILTER_ACTION_STOP = 0,
547 PERF_ADDR_FILTER_ACTION_START,
548 PERF_ADDR_FILTER_ACTION_FILTER,
549 };
550
551 /**
552 * struct perf_addr_filter - address range filter definition
553 * @entry: event's filter list linkage
554 * @path: object file's path for file-based filters
555 * @offset: filter range offset
556 * @size: filter range size (size==0 means single address trigger)
557 * @action: filter/start/stop
558 *
559 * This is a hardware-agnostic filter configuration as specified by the user.
560 */
561 struct perf_addr_filter {
562 struct list_head entry;
563 struct path path;
564 unsigned long offset;
565 unsigned long size;
566 enum perf_addr_filter_action_t action;
567 };
568
569 /**
570 * struct perf_addr_filters_head - container for address range filters
571 * @list: list of filters for this event
572 * @lock: spinlock that serializes accesses to the @list and event's
573 * (and its children's) filter generations.
574 * @nr_file_filters: number of file-based filters
575 *
576 * A child event will use parent's @list (and therefore @lock), so they are
577 * bundled together; see perf_event_addr_filters().
578 */
579 struct perf_addr_filters_head {
580 struct list_head list;
581 raw_spinlock_t lock;
582 unsigned int nr_file_filters;
583 };
584
585 struct perf_addr_filter_range {
586 unsigned long start;
587 unsigned long size;
588 };
589
590 /**
591 * enum perf_event_state - the states of an event:
592 */
593 enum perf_event_state {
594 PERF_EVENT_STATE_DEAD = -4,
595 PERF_EVENT_STATE_EXIT = -3,
596 PERF_EVENT_STATE_ERROR = -2,
597 PERF_EVENT_STATE_OFF = -1,
598 PERF_EVENT_STATE_INACTIVE = 0,
599 PERF_EVENT_STATE_ACTIVE = 1,
600 };
601
602 struct file;
603 struct perf_sample_data;
604
605 typedef void (*perf_overflow_handler_t)(struct perf_event *,
606 struct perf_sample_data *,
607 struct pt_regs *regs);
608
609 /*
610 * Event capabilities. For event_caps and groups caps.
611 *
612 * PERF_EV_CAP_SOFTWARE: Is a software event.
613 * PERF_EV_CAP_READ_ACTIVE_PKG: A CPU event (or cgroup event) that can be read
614 * from any CPU in the package where it is active.
615 * PERF_EV_CAP_SIBLING: An event with this flag must be a group sibling and
616 * cannot be a group leader. If an event with this flag is detached from the
617 * group it is scheduled out and moved into an unrecoverable ERROR state.
618 */
619 #define PERF_EV_CAP_SOFTWARE BIT(0)
620 #define PERF_EV_CAP_READ_ACTIVE_PKG BIT(1)
621 #define PERF_EV_CAP_SIBLING BIT(2)
622
623 #define SWEVENT_HLIST_BITS 8
624 #define SWEVENT_HLIST_SIZE (1 << SWEVENT_HLIST_BITS)
625
626 struct swevent_hlist {
627 struct hlist_head heads[SWEVENT_HLIST_SIZE];
628 struct rcu_head rcu_head;
629 };
630
631 #define PERF_ATTACH_CONTEXT 0x01
632 #define PERF_ATTACH_GROUP 0x02
633 #define PERF_ATTACH_TASK 0x04
634 #define PERF_ATTACH_TASK_DATA 0x08
635 #define PERF_ATTACH_ITRACE 0x10
636 #define PERF_ATTACH_SCHED_CB 0x20
637 #define PERF_ATTACH_CHILD 0x40
638
639 struct bpf_prog;
640 struct perf_cgroup;
641 struct perf_buffer;
642
643 struct pmu_event_list {
644 raw_spinlock_t lock;
645 struct list_head list;
646 };
647
648 /*
649 * event->sibling_list is modified whole holding both ctx->lock and ctx->mutex
650 * as such iteration must hold either lock. However, since ctx->lock is an IRQ
651 * safe lock, and is only held by the CPU doing the modification, having IRQs
652 * disabled is sufficient since it will hold-off the IPIs.
653 */
654 #ifdef CONFIG_PROVE_LOCKING
655 #define lockdep_assert_event_ctx(event) \
656 WARN_ON_ONCE(__lockdep_enabled && \
657 (this_cpu_read(hardirqs_enabled) && \
658 lockdep_is_held(&(event)->ctx->mutex) != LOCK_STATE_HELD))
659 #else
660 #define lockdep_assert_event_ctx(event)
661 #endif
662
663 #define for_each_sibling_event(sibling, event) \
664 lockdep_assert_event_ctx(event); \
665 if ((event)->group_leader == (event)) \
666 list_for_each_entry((sibling), &(event)->sibling_list, sibling_list)
667
668 /**
669 * struct perf_event - performance event kernel representation:
670 */
671 struct perf_event {
672 #ifdef CONFIG_PERF_EVENTS
673 /*
674 * entry onto perf_event_context::event_list;
675 * modifications require ctx->lock
676 * RCU safe iterations.
677 */
678 struct list_head event_entry;
679
680 /*
681 * Locked for modification by both ctx->mutex and ctx->lock; holding
682 * either sufficies for read.
683 */
684 struct list_head sibling_list;
685 struct list_head active_list;
686 /*
687 * Node on the pinned or flexible tree located at the event context;
688 */
689 struct rb_node group_node;
690 u64 group_index;
691 /*
692 * We need storage to track the entries in perf_pmu_migrate_context; we
693 * cannot use the event_entry because of RCU and we want to keep the
694 * group in tact which avoids us using the other two entries.
695 */
696 struct list_head migrate_entry;
697
698 struct hlist_node hlist_entry;
699 struct list_head active_entry;
700 int nr_siblings;
701
702 /* Not serialized. Only written during event initialization. */
703 int event_caps;
704 /* The cumulative AND of all event_caps for events in this group. */
705 int group_caps;
706
707 unsigned int group_generation;
708 struct perf_event *group_leader;
709 /*
710 * event->pmu will always point to pmu in which this event belongs.
711 * Whereas event->pmu_ctx->pmu may point to other pmu when group of
712 * different pmu events is created.
713 */
714 struct pmu *pmu;
715 void *pmu_private;
716
717 enum perf_event_state state;
718 unsigned int attach_state;
719 local64_t count;
720 atomic64_t child_count;
721
722 /*
723 * These are the total time in nanoseconds that the event
724 * has been enabled (i.e. eligible to run, and the task has
725 * been scheduled in, if this is a per-task event)
726 * and running (scheduled onto the CPU), respectively.
727 */
728 u64 total_time_enabled;
729 u64 total_time_running;
730 u64 tstamp;
731
732 struct perf_event_attr attr;
733 u16 header_size;
734 u16 id_header_size;
735 u16 read_size;
736 struct hw_perf_event hw;
737
738 struct perf_event_context *ctx;
739 /*
740 * event->pmu_ctx points to perf_event_pmu_context in which the event
741 * is added. This pmu_ctx can be of other pmu for sw event when that
742 * sw event is part of a group which also contains non-sw events.
743 */
744 struct perf_event_pmu_context *pmu_ctx;
745 atomic_long_t refcount;
746
747 /*
748 * These accumulate total time (in nanoseconds) that children
749 * events have been enabled and running, respectively.
750 */
751 atomic64_t child_total_time_enabled;
752 atomic64_t child_total_time_running;
753
754 /*
755 * Protect attach/detach and child_list:
756 */
757 struct mutex child_mutex;
758 struct list_head child_list;
759 struct perf_event *parent;
760
761 int oncpu;
762 int cpu;
763
764 struct list_head owner_entry;
765 struct task_struct *owner;
766
767 /* mmap bits */
768 struct mutex mmap_mutex;
769 atomic_t mmap_count;
770
771 struct perf_buffer *rb;
772 struct list_head rb_entry;
773 unsigned long rcu_batches;
774 int rcu_pending;
775
776 /* poll related */
777 wait_queue_head_t waitq;
778 struct fasync_struct *fasync;
779
780 /* delayed work for NMIs and such */
781 unsigned int pending_wakeup;
782 unsigned int pending_kill;
783 unsigned int pending_disable;
784 unsigned int pending_sigtrap;
785 unsigned long pending_addr; /* SIGTRAP */
786 struct irq_work pending_irq;
787 struct callback_head pending_task;
788 unsigned int pending_work;
789
790 atomic_t event_limit;
791
792 /* address range filters */
793 struct perf_addr_filters_head addr_filters;
794 /* vma address array for file-based filders */
795 struct perf_addr_filter_range *addr_filter_ranges;
796 unsigned long addr_filters_gen;
797
798 /* for aux_output events */
799 struct perf_event *aux_event;
800
801 void (*destroy)(struct perf_event *);
802 struct rcu_head rcu_head;
803
804 struct pid_namespace *ns;
805 u64 id;
806
807 atomic64_t lost_samples;
808
809 u64 (*clock)(void);
810 perf_overflow_handler_t overflow_handler;
811 void *overflow_handler_context;
812 struct bpf_prog *prog;
813 u64 bpf_cookie;
814
815 #ifdef CONFIG_EVENT_TRACING
816 struct trace_event_call *tp_event;
817 struct event_filter *filter;
818 #ifdef CONFIG_FUNCTION_TRACER
819 struct ftrace_ops ftrace_ops;
820 #endif
821 #endif
822
823 #ifdef CONFIG_CGROUP_PERF
824 struct perf_cgroup *cgrp; /* cgroup event is attach to */
825 #endif
826
827 #ifdef CONFIG_SECURITY
828 void *security;
829 #endif
830 struct list_head sb_list;
831
832 /*
833 * Certain events gets forwarded to another pmu internally by over-
834 * writing kernel copy of event->attr.type without user being aware
835 * of it. event->orig_type contains original 'type' requested by
836 * user.
837 */
838 __u32 orig_type;
839 #endif /* CONFIG_PERF_EVENTS */
840 };
841
842 /*
843 * ,-----------------------[1:n]------------------------.
844 * V V
845 * perf_event_context <-[1:n]-> perf_event_pmu_context <-[1:n]- perf_event
846 * | |
847 * `--[n:1]-> pmu <-[1:n]--'
848 *
849 *
850 * struct perf_event_pmu_context lifetime is refcount based and RCU freed
851 * (similar to perf_event_context). Locking is as if it were a member of
852 * perf_event_context; specifically:
853 *
854 * modification, both: ctx->mutex && ctx->lock
855 * reading, either: ctx->mutex || ctx->lock
856 *
857 * There is one exception to this; namely put_pmu_ctx() isn't always called
858 * with ctx->mutex held; this means that as long as we can guarantee the epc
859 * has events the above rules hold.
860 *
861 * Specificially, sys_perf_event_open()'s group_leader case depends on
862 * ctx->mutex pinning the configuration. Since we hold a reference on
863 * group_leader (through the filedesc) it can't go away, therefore it's
864 * associated pmu_ctx must exist and cannot change due to ctx->mutex.
865 *
866 * perf_event holds a refcount on perf_event_context
867 * perf_event holds a refcount on perf_event_pmu_context
868 */
869 struct perf_event_pmu_context {
870 struct pmu *pmu;
871 struct perf_event_context *ctx;
872
873 struct list_head pmu_ctx_entry;
874
875 struct list_head pinned_active;
876 struct list_head flexible_active;
877
878 /* Used to avoid freeing per-cpu perf_event_pmu_context */
879 unsigned int embedded : 1;
880
881 unsigned int nr_events;
882 unsigned int nr_cgroups;
883 unsigned int nr_freq;
884
885 atomic_t refcount; /* event <-> epc */
886 struct rcu_head rcu_head;
887
888 void *task_ctx_data; /* pmu specific data */
889 /*
890 * Set when one or more (plausibly active) event can't be scheduled
891 * due to pmu overcommit or pmu constraints, except tolerant to
892 * events not necessary to be active due to scheduling constraints,
893 * such as cgroups.
894 */
895 int rotate_necessary;
896 };
897
perf_pmu_ctx_is_active(struct perf_event_pmu_context * epc)898 static inline bool perf_pmu_ctx_is_active(struct perf_event_pmu_context *epc)
899 {
900 return !list_empty(&epc->flexible_active) || !list_empty(&epc->pinned_active);
901 }
902
903 struct perf_event_groups {
904 struct rb_root tree;
905 u64 index;
906 };
907
908
909 /**
910 * struct perf_event_context - event context structure
911 *
912 * Used as a container for task events and CPU events as well:
913 */
914 struct perf_event_context {
915 /*
916 * Protect the states of the events in the list,
917 * nr_active, and the list:
918 */
919 raw_spinlock_t lock;
920 /*
921 * Protect the list of events. Locking either mutex or lock
922 * is sufficient to ensure the list doesn't change; to change
923 * the list you need to lock both the mutex and the spinlock.
924 */
925 struct mutex mutex;
926
927 struct list_head pmu_ctx_list;
928 struct perf_event_groups pinned_groups;
929 struct perf_event_groups flexible_groups;
930 struct list_head event_list;
931
932 int nr_events;
933 int nr_user;
934 int is_active;
935
936 int nr_task_data;
937 int nr_stat;
938 int nr_freq;
939 int rotate_disable;
940
941 refcount_t refcount; /* event <-> ctx */
942 struct task_struct *task;
943
944 /*
945 * Context clock, runs when context enabled.
946 */
947 u64 time;
948 u64 timestamp;
949 u64 timeoffset;
950
951 /*
952 * These fields let us detect when two contexts have both
953 * been cloned (inherited) from a common ancestor.
954 */
955 struct perf_event_context *parent_ctx;
956 u64 parent_gen;
957 u64 generation;
958 int pin_count;
959 #ifdef CONFIG_CGROUP_PERF
960 int nr_cgroups; /* cgroup evts */
961 #endif
962 struct rcu_head rcu_head;
963
964 /*
965 * Sum (event->pending_sigtrap + event->pending_work)
966 *
967 * The SIGTRAP is targeted at ctx->task, as such it won't do changing
968 * that until the signal is delivered.
969 */
970 local_t nr_pending;
971 };
972
973 /*
974 * Number of contexts where an event can trigger:
975 * task, softirq, hardirq, nmi.
976 */
977 #define PERF_NR_CONTEXTS 4
978
979 struct perf_cpu_pmu_context {
980 struct perf_event_pmu_context epc;
981 struct perf_event_pmu_context *task_epc;
982
983 struct list_head sched_cb_entry;
984 int sched_cb_usage;
985
986 int active_oncpu;
987 int exclusive;
988
989 raw_spinlock_t hrtimer_lock;
990 struct hrtimer hrtimer;
991 ktime_t hrtimer_interval;
992 unsigned int hrtimer_active;
993 };
994
995 /**
996 * struct perf_event_cpu_context - per cpu event context structure
997 */
998 struct perf_cpu_context {
999 struct perf_event_context ctx;
1000 struct perf_event_context *task_ctx;
1001 int online;
1002
1003 #ifdef CONFIG_CGROUP_PERF
1004 struct perf_cgroup *cgrp;
1005 #endif
1006
1007 /*
1008 * Per-CPU storage for iterators used in visit_groups_merge. The default
1009 * storage is of size 2 to hold the CPU and any CPU event iterators.
1010 */
1011 int heap_size;
1012 struct perf_event **heap;
1013 struct perf_event *heap_default[2];
1014 };
1015
1016 struct perf_output_handle {
1017 struct perf_event *event;
1018 struct perf_buffer *rb;
1019 unsigned long wakeup;
1020 unsigned long size;
1021 u64 aux_flags;
1022 union {
1023 void *addr;
1024 unsigned long head;
1025 };
1026 int page;
1027 };
1028
1029 struct bpf_perf_event_data_kern {
1030 bpf_user_pt_regs_t *regs;
1031 struct perf_sample_data *data;
1032 struct perf_event *event;
1033 };
1034
1035 #ifdef CONFIG_CGROUP_PERF
1036
1037 /*
1038 * perf_cgroup_info keeps track of time_enabled for a cgroup.
1039 * This is a per-cpu dynamically allocated data structure.
1040 */
1041 struct perf_cgroup_info {
1042 u64 time;
1043 u64 timestamp;
1044 u64 timeoffset;
1045 int active;
1046 };
1047
1048 struct perf_cgroup {
1049 struct cgroup_subsys_state css;
1050 struct perf_cgroup_info __percpu *info;
1051 };
1052
1053 /*
1054 * Must ensure cgroup is pinned (css_get) before calling
1055 * this function. In other words, we cannot call this function
1056 * if there is no cgroup event for the current CPU context.
1057 */
1058 static inline struct perf_cgroup *
perf_cgroup_from_task(struct task_struct * task,struct perf_event_context * ctx)1059 perf_cgroup_from_task(struct task_struct *task, struct perf_event_context *ctx)
1060 {
1061 return container_of(task_css_check(task, perf_event_cgrp_id,
1062 ctx ? lockdep_is_held(&ctx->lock)
1063 : true),
1064 struct perf_cgroup, css);
1065 }
1066 #endif /* CONFIG_CGROUP_PERF */
1067
1068 #ifdef CONFIG_PERF_EVENTS
1069
1070 extern struct perf_event_context *perf_cpu_task_ctx(void);
1071
1072 extern void *perf_aux_output_begin(struct perf_output_handle *handle,
1073 struct perf_event *event);
1074 extern void perf_aux_output_end(struct perf_output_handle *handle,
1075 unsigned long size);
1076 extern int perf_aux_output_skip(struct perf_output_handle *handle,
1077 unsigned long size);
1078 extern void *perf_get_aux(struct perf_output_handle *handle);
1079 extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
1080 extern void perf_event_itrace_started(struct perf_event *event);
1081
1082 extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
1083 extern void perf_pmu_unregister(struct pmu *pmu);
1084
1085 extern void __perf_event_task_sched_in(struct task_struct *prev,
1086 struct task_struct *task);
1087 extern void __perf_event_task_sched_out(struct task_struct *prev,
1088 struct task_struct *next);
1089 extern int perf_event_init_task(struct task_struct *child, u64 clone_flags);
1090 extern void perf_event_exit_task(struct task_struct *child);
1091 extern void perf_event_free_task(struct task_struct *task);
1092 extern void perf_event_delayed_put(struct task_struct *task);
1093 extern struct file *perf_event_get(unsigned int fd);
1094 extern const struct perf_event *perf_get_event(struct file *file);
1095 extern const struct perf_event_attr *perf_event_attrs(struct perf_event *event);
1096 extern void perf_event_print_debug(void);
1097 extern void perf_pmu_disable(struct pmu *pmu);
1098 extern void perf_pmu_enable(struct pmu *pmu);
1099 extern void perf_sched_cb_dec(struct pmu *pmu);
1100 extern void perf_sched_cb_inc(struct pmu *pmu);
1101 extern int perf_event_task_disable(void);
1102 extern int perf_event_task_enable(void);
1103
1104 extern void perf_pmu_resched(struct pmu *pmu);
1105
1106 extern int perf_event_refresh(struct perf_event *event, int refresh);
1107 extern void perf_event_update_userpage(struct perf_event *event);
1108 extern int perf_event_release_kernel(struct perf_event *event);
1109 extern struct perf_event *
1110 perf_event_create_kernel_counter(struct perf_event_attr *attr,
1111 int cpu,
1112 struct task_struct *task,
1113 perf_overflow_handler_t callback,
1114 void *context);
1115 extern void perf_pmu_migrate_context(struct pmu *pmu,
1116 int src_cpu, int dst_cpu);
1117 int perf_event_read_local(struct perf_event *event, u64 *value,
1118 u64 *enabled, u64 *running);
1119 extern u64 perf_event_read_value(struct perf_event *event,
1120 u64 *enabled, u64 *running);
1121
1122 extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, struct pt_regs *regs);
1123
branch_sample_no_flags(const struct perf_event * event)1124 static inline bool branch_sample_no_flags(const struct perf_event *event)
1125 {
1126 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_NO_FLAGS;
1127 }
1128
branch_sample_no_cycles(const struct perf_event * event)1129 static inline bool branch_sample_no_cycles(const struct perf_event *event)
1130 {
1131 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_NO_CYCLES;
1132 }
1133
branch_sample_type(const struct perf_event * event)1134 static inline bool branch_sample_type(const struct perf_event *event)
1135 {
1136 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_TYPE_SAVE;
1137 }
1138
branch_sample_hw_index(const struct perf_event * event)1139 static inline bool branch_sample_hw_index(const struct perf_event *event)
1140 {
1141 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX;
1142 }
1143
branch_sample_priv(const struct perf_event * event)1144 static inline bool branch_sample_priv(const struct perf_event *event)
1145 {
1146 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_PRIV_SAVE;
1147 }
1148
branch_sample_counters(const struct perf_event * event)1149 static inline bool branch_sample_counters(const struct perf_event *event)
1150 {
1151 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS;
1152 }
1153
branch_sample_call_stack(const struct perf_event * event)1154 static inline bool branch_sample_call_stack(const struct perf_event *event)
1155 {
1156 return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK;
1157 }
1158
1159 struct perf_sample_data {
1160 /*
1161 * Fields set by perf_sample_data_init() unconditionally,
1162 * group so as to minimize the cachelines touched.
1163 */
1164 u64 sample_flags;
1165 u64 period;
1166 u64 dyn_size;
1167
1168 /*
1169 * Fields commonly set by __perf_event_header__init_id(),
1170 * group so as to minimize the cachelines touched.
1171 */
1172 u64 type;
1173 struct {
1174 u32 pid;
1175 u32 tid;
1176 } tid_entry;
1177 u64 time;
1178 u64 id;
1179 struct {
1180 u32 cpu;
1181 u32 reserved;
1182 } cpu_entry;
1183
1184 /*
1185 * The other fields, optionally {set,used} by
1186 * perf_{prepare,output}_sample().
1187 */
1188 u64 ip;
1189 struct perf_callchain_entry *callchain;
1190 struct perf_raw_record *raw;
1191 struct perf_branch_stack *br_stack;
1192 u64 *br_stack_cntr;
1193 union perf_sample_weight weight;
1194 union perf_mem_data_src data_src;
1195 u64 txn;
1196
1197 struct perf_regs regs_user;
1198 struct perf_regs regs_intr;
1199 u64 stack_user_size;
1200
1201 u64 stream_id;
1202 u64 cgroup;
1203 u64 addr;
1204 u64 phys_addr;
1205 u64 data_page_size;
1206 u64 code_page_size;
1207 u64 aux_size;
1208 } ____cacheline_aligned;
1209
1210 /* default value for data source */
1211 #define PERF_MEM_NA (PERF_MEM_S(OP, NA) |\
1212 PERF_MEM_S(LVL, NA) |\
1213 PERF_MEM_S(SNOOP, NA) |\
1214 PERF_MEM_S(LOCK, NA) |\
1215 PERF_MEM_S(TLB, NA) |\
1216 PERF_MEM_S(LVLNUM, NA))
1217
perf_sample_data_init(struct perf_sample_data * data,u64 addr,u64 period)1218 static inline void perf_sample_data_init(struct perf_sample_data *data,
1219 u64 addr, u64 period)
1220 {
1221 /* remaining struct members initialized in perf_prepare_sample() */
1222 data->sample_flags = PERF_SAMPLE_PERIOD;
1223 data->period = period;
1224 data->dyn_size = 0;
1225
1226 if (addr) {
1227 data->addr = addr;
1228 data->sample_flags |= PERF_SAMPLE_ADDR;
1229 }
1230 }
1231
perf_sample_save_callchain(struct perf_sample_data * data,struct perf_event * event,struct pt_regs * regs)1232 static inline void perf_sample_save_callchain(struct perf_sample_data *data,
1233 struct perf_event *event,
1234 struct pt_regs *regs)
1235 {
1236 int size = 1;
1237
1238 data->callchain = perf_callchain(event, regs);
1239 size += data->callchain->nr;
1240
1241 data->dyn_size += size * sizeof(u64);
1242 data->sample_flags |= PERF_SAMPLE_CALLCHAIN;
1243 }
1244
perf_sample_save_raw_data(struct perf_sample_data * data,struct perf_raw_record * raw)1245 static inline void perf_sample_save_raw_data(struct perf_sample_data *data,
1246 struct perf_raw_record *raw)
1247 {
1248 struct perf_raw_frag *frag = &raw->frag;
1249 u32 sum = 0;
1250 int size;
1251
1252 do {
1253 sum += frag->size;
1254 if (perf_raw_frag_last(frag))
1255 break;
1256 frag = frag->next;
1257 } while (1);
1258
1259 size = round_up(sum + sizeof(u32), sizeof(u64));
1260 raw->size = size - sizeof(u32);
1261 frag->pad = raw->size - sum;
1262
1263 data->raw = raw;
1264 data->dyn_size += size;
1265 data->sample_flags |= PERF_SAMPLE_RAW;
1266 }
1267
perf_sample_save_brstack(struct perf_sample_data * data,struct perf_event * event,struct perf_branch_stack * brs,u64 * brs_cntr)1268 static inline void perf_sample_save_brstack(struct perf_sample_data *data,
1269 struct perf_event *event,
1270 struct perf_branch_stack *brs,
1271 u64 *brs_cntr)
1272 {
1273 int size = sizeof(u64); /* nr */
1274
1275 if (branch_sample_hw_index(event))
1276 size += sizeof(u64);
1277 size += brs->nr * sizeof(struct perf_branch_entry);
1278
1279 /*
1280 * The extension space for counters is appended after the
1281 * struct perf_branch_stack. It is used to store the occurrences
1282 * of events of each branch.
1283 */
1284 if (brs_cntr)
1285 size += brs->nr * sizeof(u64);
1286
1287 data->br_stack = brs;
1288 data->br_stack_cntr = brs_cntr;
1289 data->dyn_size += size;
1290 data->sample_flags |= PERF_SAMPLE_BRANCH_STACK;
1291 }
1292
perf_sample_data_size(struct perf_sample_data * data,struct perf_event * event)1293 static inline u32 perf_sample_data_size(struct perf_sample_data *data,
1294 struct perf_event *event)
1295 {
1296 u32 size = sizeof(struct perf_event_header);
1297
1298 size += event->header_size + event->id_header_size;
1299 size += data->dyn_size;
1300
1301 return size;
1302 }
1303
1304 /*
1305 * Clear all bitfields in the perf_branch_entry.
1306 * The to and from fields are not cleared because they are
1307 * systematically modified by caller.
1308 */
perf_clear_branch_entry_bitfields(struct perf_branch_entry * br)1309 static inline void perf_clear_branch_entry_bitfields(struct perf_branch_entry *br)
1310 {
1311 br->mispred = 0;
1312 br->predicted = 0;
1313 br->in_tx = 0;
1314 br->abort = 0;
1315 br->cycles = 0;
1316 br->type = 0;
1317 br->spec = PERF_BR_SPEC_NA;
1318 br->reserved = 0;
1319 }
1320
1321 extern void perf_output_sample(struct perf_output_handle *handle,
1322 struct perf_event_header *header,
1323 struct perf_sample_data *data,
1324 struct perf_event *event);
1325 extern void perf_prepare_sample(struct perf_sample_data *data,
1326 struct perf_event *event,
1327 struct pt_regs *regs);
1328 extern void perf_prepare_header(struct perf_event_header *header,
1329 struct perf_sample_data *data,
1330 struct perf_event *event,
1331 struct pt_regs *regs);
1332
1333 extern int perf_event_overflow(struct perf_event *event,
1334 struct perf_sample_data *data,
1335 struct pt_regs *regs);
1336
1337 extern void perf_event_output_forward(struct perf_event *event,
1338 struct perf_sample_data *data,
1339 struct pt_regs *regs);
1340 extern void perf_event_output_backward(struct perf_event *event,
1341 struct perf_sample_data *data,
1342 struct pt_regs *regs);
1343 extern int perf_event_output(struct perf_event *event,
1344 struct perf_sample_data *data,
1345 struct pt_regs *regs);
1346
1347 static inline bool
is_default_overflow_handler(struct perf_event * event)1348 is_default_overflow_handler(struct perf_event *event)
1349 {
1350 perf_overflow_handler_t overflow_handler = event->overflow_handler;
1351
1352 if (likely(overflow_handler == perf_event_output_forward))
1353 return true;
1354 if (unlikely(overflow_handler == perf_event_output_backward))
1355 return true;
1356 return false;
1357 }
1358
1359 extern void
1360 perf_event_header__init_id(struct perf_event_header *header,
1361 struct perf_sample_data *data,
1362 struct perf_event *event);
1363 extern void
1364 perf_event__output_id_sample(struct perf_event *event,
1365 struct perf_output_handle *handle,
1366 struct perf_sample_data *sample);
1367
1368 extern void
1369 perf_log_lost_samples(struct perf_event *event, u64 lost);
1370
event_has_any_exclude_flag(struct perf_event * event)1371 static inline bool event_has_any_exclude_flag(struct perf_event *event)
1372 {
1373 struct perf_event_attr *attr = &event->attr;
1374
1375 return attr->exclude_idle || attr->exclude_user ||
1376 attr->exclude_kernel || attr->exclude_hv ||
1377 attr->exclude_guest || attr->exclude_host;
1378 }
1379
is_sampling_event(struct perf_event * event)1380 static inline bool is_sampling_event(struct perf_event *event)
1381 {
1382 return event->attr.sample_period != 0;
1383 }
1384
1385 /*
1386 * Return 1 for a software event, 0 for a hardware event
1387 */
is_software_event(struct perf_event * event)1388 static inline int is_software_event(struct perf_event *event)
1389 {
1390 return event->event_caps & PERF_EV_CAP_SOFTWARE;
1391 }
1392
1393 /*
1394 * Return 1 for event in sw context, 0 for event in hw context
1395 */
in_software_context(struct perf_event * event)1396 static inline int in_software_context(struct perf_event *event)
1397 {
1398 return event->pmu_ctx->pmu->task_ctx_nr == perf_sw_context;
1399 }
1400
is_exclusive_pmu(struct pmu * pmu)1401 static inline int is_exclusive_pmu(struct pmu *pmu)
1402 {
1403 return pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE;
1404 }
1405
1406 extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
1407
1408 extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
1409 extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
1410
1411 #ifndef perf_arch_fetch_caller_regs
perf_arch_fetch_caller_regs(struct pt_regs * regs,unsigned long ip)1412 static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
1413 #endif
1414
1415 /*
1416 * When generating a perf sample in-line, instead of from an interrupt /
1417 * exception, we lack a pt_regs. This is typically used from software events
1418 * like: SW_CONTEXT_SWITCHES, SW_MIGRATIONS and the tie-in with tracepoints.
1419 *
1420 * We typically don't need a full set, but (for x86) do require:
1421 * - ip for PERF_SAMPLE_IP
1422 * - cs for user_mode() tests
1423 * - sp for PERF_SAMPLE_CALLCHAIN
1424 * - eflags for MISC bits and CALLCHAIN (see: perf_hw_regs())
1425 *
1426 * NOTE: assumes @regs is otherwise already 0 filled; this is important for
1427 * things like PERF_SAMPLE_REGS_INTR.
1428 */
perf_fetch_caller_regs(struct pt_regs * regs)1429 static inline void perf_fetch_caller_regs(struct pt_regs *regs)
1430 {
1431 perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
1432 }
1433
1434 static __always_inline void
perf_sw_event(u32 event_id,u64 nr,struct pt_regs * regs,u64 addr)1435 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
1436 {
1437 if (static_key_false(&perf_swevent_enabled[event_id]))
1438 __perf_sw_event(event_id, nr, regs, addr);
1439 }
1440
1441 DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);
1442
1443 /*
1444 * 'Special' version for the scheduler, it hard assumes no recursion,
1445 * which is guaranteed by us not actually scheduling inside other swevents
1446 * because those disable preemption.
1447 */
__perf_sw_event_sched(u32 event_id,u64 nr,u64 addr)1448 static __always_inline void __perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
1449 {
1450 struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
1451
1452 perf_fetch_caller_regs(regs);
1453 ___perf_sw_event(event_id, nr, regs, addr);
1454 }
1455
1456 extern struct static_key_false perf_sched_events;
1457
__perf_sw_enabled(int swevt)1458 static __always_inline bool __perf_sw_enabled(int swevt)
1459 {
1460 return static_key_false(&perf_swevent_enabled[swevt]);
1461 }
1462
perf_event_task_migrate(struct task_struct * task)1463 static inline void perf_event_task_migrate(struct task_struct *task)
1464 {
1465 if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS))
1466 task->sched_migrated = 1;
1467 }
1468
perf_event_task_sched_in(struct task_struct * prev,struct task_struct * task)1469 static inline void perf_event_task_sched_in(struct task_struct *prev,
1470 struct task_struct *task)
1471 {
1472 if (static_branch_unlikely(&perf_sched_events))
1473 __perf_event_task_sched_in(prev, task);
1474
1475 if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS) &&
1476 task->sched_migrated) {
1477 __perf_sw_event_sched(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 0);
1478 task->sched_migrated = 0;
1479 }
1480 }
1481
perf_event_task_sched_out(struct task_struct * prev,struct task_struct * next)1482 static inline void perf_event_task_sched_out(struct task_struct *prev,
1483 struct task_struct *next)
1484 {
1485 if (__perf_sw_enabled(PERF_COUNT_SW_CONTEXT_SWITCHES))
1486 __perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);
1487
1488 #ifdef CONFIG_CGROUP_PERF
1489 if (__perf_sw_enabled(PERF_COUNT_SW_CGROUP_SWITCHES) &&
1490 perf_cgroup_from_task(prev, NULL) !=
1491 perf_cgroup_from_task(next, NULL))
1492 __perf_sw_event_sched(PERF_COUNT_SW_CGROUP_SWITCHES, 1, 0);
1493 #endif
1494
1495 if (static_branch_unlikely(&perf_sched_events))
1496 __perf_event_task_sched_out(prev, next);
1497 }
1498
1499 extern void perf_event_mmap(struct vm_area_struct *vma);
1500
1501 extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1502 bool unregister, const char *sym);
1503 extern void perf_event_bpf_event(struct bpf_prog *prog,
1504 enum perf_bpf_event_type type,
1505 u16 flags);
1506
1507 #ifdef CONFIG_GUEST_PERF_EVENTS
1508 extern struct perf_guest_info_callbacks __rcu *perf_guest_cbs;
1509
1510 DECLARE_STATIC_CALL(__perf_guest_state, *perf_guest_cbs->state);
1511 DECLARE_STATIC_CALL(__perf_guest_get_ip, *perf_guest_cbs->get_ip);
1512 DECLARE_STATIC_CALL(__perf_guest_handle_intel_pt_intr, *perf_guest_cbs->handle_intel_pt_intr);
1513
perf_guest_state(void)1514 static inline unsigned int perf_guest_state(void)
1515 {
1516 return static_call(__perf_guest_state)();
1517 }
perf_guest_get_ip(void)1518 static inline unsigned long perf_guest_get_ip(void)
1519 {
1520 return static_call(__perf_guest_get_ip)();
1521 }
perf_guest_handle_intel_pt_intr(void)1522 static inline unsigned int perf_guest_handle_intel_pt_intr(void)
1523 {
1524 return static_call(__perf_guest_handle_intel_pt_intr)();
1525 }
1526 extern void perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs);
1527 extern void perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs);
1528 #else
perf_guest_state(void)1529 static inline unsigned int perf_guest_state(void) { return 0; }
perf_guest_get_ip(void)1530 static inline unsigned long perf_guest_get_ip(void) { return 0; }
perf_guest_handle_intel_pt_intr(void)1531 static inline unsigned int perf_guest_handle_intel_pt_intr(void) { return 0; }
1532 #endif /* CONFIG_GUEST_PERF_EVENTS */
1533
1534 extern void perf_event_exec(void);
1535 extern void perf_event_comm(struct task_struct *tsk, bool exec);
1536 extern void perf_event_namespaces(struct task_struct *tsk);
1537 extern void perf_event_fork(struct task_struct *tsk);
1538 extern void perf_event_text_poke(const void *addr,
1539 const void *old_bytes, size_t old_len,
1540 const void *new_bytes, size_t new_len);
1541
1542 /* Callchains */
1543 DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
1544
1545 extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1546 extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1547 extern struct perf_callchain_entry *
1548 get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
1549 u32 max_stack, bool crosstask, bool add_mark);
1550 extern int get_callchain_buffers(int max_stack);
1551 extern void put_callchain_buffers(void);
1552 extern struct perf_callchain_entry *get_callchain_entry(int *rctx);
1553 extern void put_callchain_entry(int rctx);
1554
1555 extern int sysctl_perf_event_max_stack;
1556 extern int sysctl_perf_event_max_contexts_per_stack;
1557
perf_callchain_store_context(struct perf_callchain_entry_ctx * ctx,u64 ip)1558 static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
1559 {
1560 if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
1561 struct perf_callchain_entry *entry = ctx->entry;
1562 entry->ip[entry->nr++] = ip;
1563 ++ctx->contexts;
1564 return 0;
1565 } else {
1566 ctx->contexts_maxed = true;
1567 return -1; /* no more room, stop walking the stack */
1568 }
1569 }
1570
perf_callchain_store(struct perf_callchain_entry_ctx * ctx,u64 ip)1571 static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
1572 {
1573 if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
1574 struct perf_callchain_entry *entry = ctx->entry;
1575 entry->ip[entry->nr++] = ip;
1576 ++ctx->nr;
1577 return 0;
1578 } else {
1579 return -1; /* no more room, stop walking the stack */
1580 }
1581 }
1582
1583 extern int sysctl_perf_event_paranoid;
1584 extern int sysctl_perf_event_mlock;
1585 extern int sysctl_perf_event_sample_rate;
1586 extern int sysctl_perf_cpu_time_max_percent;
1587
1588 extern void perf_sample_event_took(u64 sample_len_ns);
1589
1590 int perf_event_max_sample_rate_handler(struct ctl_table *table, int write,
1591 void *buffer, size_t *lenp, loff_t *ppos);
1592 int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
1593 void *buffer, size_t *lenp, loff_t *ppos);
1594 int perf_event_max_stack_handler(struct ctl_table *table, int write,
1595 void *buffer, size_t *lenp, loff_t *ppos);
1596
1597 /* Access to perf_event_open(2) syscall. */
1598 #define PERF_SECURITY_OPEN 0
1599
1600 /* Finer grained perf_event_open(2) access control. */
1601 #define PERF_SECURITY_CPU 1
1602 #define PERF_SECURITY_KERNEL 2
1603 #define PERF_SECURITY_TRACEPOINT 3
1604
perf_is_paranoid(void)1605 static inline int perf_is_paranoid(void)
1606 {
1607 return sysctl_perf_event_paranoid > -1;
1608 }
1609
perf_allow_kernel(struct perf_event_attr * attr)1610 static inline int perf_allow_kernel(struct perf_event_attr *attr)
1611 {
1612 if (sysctl_perf_event_paranoid > 1 && !perfmon_capable())
1613 return -EACCES;
1614
1615 return security_perf_event_open(attr, PERF_SECURITY_KERNEL);
1616 }
1617
perf_allow_cpu(struct perf_event_attr * attr)1618 static inline int perf_allow_cpu(struct perf_event_attr *attr)
1619 {
1620 if (sysctl_perf_event_paranoid > 0 && !perfmon_capable())
1621 return -EACCES;
1622
1623 return security_perf_event_open(attr, PERF_SECURITY_CPU);
1624 }
1625
perf_allow_tracepoint(struct perf_event_attr * attr)1626 static inline int perf_allow_tracepoint(struct perf_event_attr *attr)
1627 {
1628 if (sysctl_perf_event_paranoid > -1 && !perfmon_capable())
1629 return -EPERM;
1630
1631 return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT);
1632 }
1633
1634 extern void perf_event_init(void);
1635 extern void perf_tp_event(u16 event_type, u64 count, void *record,
1636 int entry_size, struct pt_regs *regs,
1637 struct hlist_head *head, int rctx,
1638 struct task_struct *task);
1639 extern void perf_bp_event(struct perf_event *event, void *data);
1640
1641 #ifndef perf_misc_flags
1642 # define perf_misc_flags(regs) \
1643 (user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
1644 # define perf_instruction_pointer(regs) instruction_pointer(regs)
1645 #endif
1646 #ifndef perf_arch_bpf_user_pt_regs
1647 # define perf_arch_bpf_user_pt_regs(regs) regs
1648 #endif
1649
has_branch_stack(struct perf_event * event)1650 static inline bool has_branch_stack(struct perf_event *event)
1651 {
1652 return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
1653 }
1654
needs_branch_stack(struct perf_event * event)1655 static inline bool needs_branch_stack(struct perf_event *event)
1656 {
1657 return event->attr.branch_sample_type != 0;
1658 }
1659
has_aux(struct perf_event * event)1660 static inline bool has_aux(struct perf_event *event)
1661 {
1662 return event->pmu->setup_aux;
1663 }
1664
is_write_backward(struct perf_event * event)1665 static inline bool is_write_backward(struct perf_event *event)
1666 {
1667 return !!event->attr.write_backward;
1668 }
1669
has_addr_filter(struct perf_event * event)1670 static inline bool has_addr_filter(struct perf_event *event)
1671 {
1672 return event->pmu->nr_addr_filters;
1673 }
1674
1675 /*
1676 * An inherited event uses parent's filters
1677 */
1678 static inline struct perf_addr_filters_head *
perf_event_addr_filters(struct perf_event * event)1679 perf_event_addr_filters(struct perf_event *event)
1680 {
1681 struct perf_addr_filters_head *ifh = &event->addr_filters;
1682
1683 if (event->parent)
1684 ifh = &event->parent->addr_filters;
1685
1686 return ifh;
1687 }
1688
perf_event_fasync(struct perf_event * event)1689 static inline struct fasync_struct **perf_event_fasync(struct perf_event *event)
1690 {
1691 /* Only the parent has fasync state */
1692 if (event->parent)
1693 event = event->parent;
1694 return &event->fasync;
1695 }
1696
1697 extern void perf_event_addr_filters_sync(struct perf_event *event);
1698 extern void perf_report_aux_output_id(struct perf_event *event, u64 hw_id);
1699
1700 extern int perf_output_begin(struct perf_output_handle *handle,
1701 struct perf_sample_data *data,
1702 struct perf_event *event, unsigned int size);
1703 extern int perf_output_begin_forward(struct perf_output_handle *handle,
1704 struct perf_sample_data *data,
1705 struct perf_event *event,
1706 unsigned int size);
1707 extern int perf_output_begin_backward(struct perf_output_handle *handle,
1708 struct perf_sample_data *data,
1709 struct perf_event *event,
1710 unsigned int size);
1711
1712 extern void perf_output_end(struct perf_output_handle *handle);
1713 extern unsigned int perf_output_copy(struct perf_output_handle *handle,
1714 const void *buf, unsigned int len);
1715 extern unsigned int perf_output_skip(struct perf_output_handle *handle,
1716 unsigned int len);
1717 extern long perf_output_copy_aux(struct perf_output_handle *aux_handle,
1718 struct perf_output_handle *handle,
1719 unsigned long from, unsigned long to);
1720 extern int perf_swevent_get_recursion_context(void);
1721 extern void perf_swevent_put_recursion_context(int rctx);
1722 extern u64 perf_swevent_set_period(struct perf_event *event);
1723 extern void perf_event_enable(struct perf_event *event);
1724 extern void perf_event_disable(struct perf_event *event);
1725 extern void perf_event_disable_local(struct perf_event *event);
1726 extern void perf_event_disable_inatomic(struct perf_event *event);
1727 extern void perf_event_task_tick(void);
1728 extern int perf_event_account_interrupt(struct perf_event *event);
1729 extern int perf_event_period(struct perf_event *event, u64 value);
1730 extern u64 perf_event_pause(struct perf_event *event, bool reset);
1731 #else /* !CONFIG_PERF_EVENTS: */
1732 static inline void *
perf_aux_output_begin(struct perf_output_handle * handle,struct perf_event * event)1733 perf_aux_output_begin(struct perf_output_handle *handle,
1734 struct perf_event *event) { return NULL; }
1735 static inline void
perf_aux_output_end(struct perf_output_handle * handle,unsigned long size)1736 perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
1737 { }
1738 static inline int
perf_aux_output_skip(struct perf_output_handle * handle,unsigned long size)1739 perf_aux_output_skip(struct perf_output_handle *handle,
1740 unsigned long size) { return -EINVAL; }
1741 static inline void *
perf_get_aux(struct perf_output_handle * handle)1742 perf_get_aux(struct perf_output_handle *handle) { return NULL; }
1743 static inline void
perf_event_task_migrate(struct task_struct * task)1744 perf_event_task_migrate(struct task_struct *task) { }
1745 static inline void
perf_event_task_sched_in(struct task_struct * prev,struct task_struct * task)1746 perf_event_task_sched_in(struct task_struct *prev,
1747 struct task_struct *task) { }
1748 static inline void
perf_event_task_sched_out(struct task_struct * prev,struct task_struct * next)1749 perf_event_task_sched_out(struct task_struct *prev,
1750 struct task_struct *next) { }
perf_event_init_task(struct task_struct * child,u64 clone_flags)1751 static inline int perf_event_init_task(struct task_struct *child,
1752 u64 clone_flags) { return 0; }
perf_event_exit_task(struct task_struct * child)1753 static inline void perf_event_exit_task(struct task_struct *child) { }
perf_event_free_task(struct task_struct * task)1754 static inline void perf_event_free_task(struct task_struct *task) { }
perf_event_delayed_put(struct task_struct * task)1755 static inline void perf_event_delayed_put(struct task_struct *task) { }
perf_event_get(unsigned int fd)1756 static inline struct file *perf_event_get(unsigned int fd) { return ERR_PTR(-EINVAL); }
perf_get_event(struct file * file)1757 static inline const struct perf_event *perf_get_event(struct file *file)
1758 {
1759 return ERR_PTR(-EINVAL);
1760 }
perf_event_attrs(struct perf_event * event)1761 static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
1762 {
1763 return ERR_PTR(-EINVAL);
1764 }
perf_event_read_local(struct perf_event * event,u64 * value,u64 * enabled,u64 * running)1765 static inline int perf_event_read_local(struct perf_event *event, u64 *value,
1766 u64 *enabled, u64 *running)
1767 {
1768 return -EINVAL;
1769 }
perf_event_print_debug(void)1770 static inline void perf_event_print_debug(void) { }
perf_event_task_disable(void)1771 static inline int perf_event_task_disable(void) { return -EINVAL; }
perf_event_task_enable(void)1772 static inline int perf_event_task_enable(void) { return -EINVAL; }
perf_event_refresh(struct perf_event * event,int refresh)1773 static inline int perf_event_refresh(struct perf_event *event, int refresh)
1774 {
1775 return -EINVAL;
1776 }
1777
1778 static inline void
perf_sw_event(u32 event_id,u64 nr,struct pt_regs * regs,u64 addr)1779 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) { }
1780 static inline void
perf_bp_event(struct perf_event * event,void * data)1781 perf_bp_event(struct perf_event *event, void *data) { }
1782
perf_event_mmap(struct vm_area_struct * vma)1783 static inline void perf_event_mmap(struct vm_area_struct *vma) { }
1784
1785 typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data);
perf_event_ksymbol(u16 ksym_type,u64 addr,u32 len,bool unregister,const char * sym)1786 static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1787 bool unregister, const char *sym) { }
perf_event_bpf_event(struct bpf_prog * prog,enum perf_bpf_event_type type,u16 flags)1788 static inline void perf_event_bpf_event(struct bpf_prog *prog,
1789 enum perf_bpf_event_type type,
1790 u16 flags) { }
perf_event_exec(void)1791 static inline void perf_event_exec(void) { }
perf_event_comm(struct task_struct * tsk,bool exec)1792 static inline void perf_event_comm(struct task_struct *tsk, bool exec) { }
perf_event_namespaces(struct task_struct * tsk)1793 static inline void perf_event_namespaces(struct task_struct *tsk) { }
perf_event_fork(struct task_struct * tsk)1794 static inline void perf_event_fork(struct task_struct *tsk) { }
perf_event_text_poke(const void * addr,const void * old_bytes,size_t old_len,const void * new_bytes,size_t new_len)1795 static inline void perf_event_text_poke(const void *addr,
1796 const void *old_bytes,
1797 size_t old_len,
1798 const void *new_bytes,
1799 size_t new_len) { }
perf_event_init(void)1800 static inline void perf_event_init(void) { }
perf_swevent_get_recursion_context(void)1801 static inline int perf_swevent_get_recursion_context(void) { return -1; }
perf_swevent_put_recursion_context(int rctx)1802 static inline void perf_swevent_put_recursion_context(int rctx) { }
perf_swevent_set_period(struct perf_event * event)1803 static inline u64 perf_swevent_set_period(struct perf_event *event) { return 0; }
perf_event_enable(struct perf_event * event)1804 static inline void perf_event_enable(struct perf_event *event) { }
perf_event_disable(struct perf_event * event)1805 static inline void perf_event_disable(struct perf_event *event) { }
__perf_event_disable(void * info)1806 static inline int __perf_event_disable(void *info) { return -1; }
perf_event_task_tick(void)1807 static inline void perf_event_task_tick(void) { }
perf_event_release_kernel(struct perf_event * event)1808 static inline int perf_event_release_kernel(struct perf_event *event) { return 0; }
perf_event_period(struct perf_event * event,u64 value)1809 static inline int perf_event_period(struct perf_event *event, u64 value)
1810 {
1811 return -EINVAL;
1812 }
perf_event_pause(struct perf_event * event,bool reset)1813 static inline u64 perf_event_pause(struct perf_event *event, bool reset)
1814 {
1815 return 0;
1816 }
1817 #endif
1818
1819 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
1820 extern void perf_restore_debug_store(void);
1821 #else
perf_restore_debug_store(void)1822 static inline void perf_restore_debug_store(void) { }
1823 #endif
1824
1825 #define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
1826
1827 struct perf_pmu_events_attr {
1828 struct device_attribute attr;
1829 u64 id;
1830 const char *event_str;
1831 };
1832
1833 struct perf_pmu_events_ht_attr {
1834 struct device_attribute attr;
1835 u64 id;
1836 const char *event_str_ht;
1837 const char *event_str_noht;
1838 };
1839
1840 struct perf_pmu_events_hybrid_attr {
1841 struct device_attribute attr;
1842 u64 id;
1843 const char *event_str;
1844 u64 pmu_type;
1845 };
1846
1847 struct perf_pmu_format_hybrid_attr {
1848 struct device_attribute attr;
1849 u64 pmu_type;
1850 };
1851
1852 ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
1853 char *page);
1854
1855 #define PMU_EVENT_ATTR(_name, _var, _id, _show) \
1856 static struct perf_pmu_events_attr _var = { \
1857 .attr = __ATTR(_name, 0444, _show, NULL), \
1858 .id = _id, \
1859 };
1860
1861 #define PMU_EVENT_ATTR_STRING(_name, _var, _str) \
1862 static struct perf_pmu_events_attr _var = { \
1863 .attr = __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
1864 .id = 0, \
1865 .event_str = _str, \
1866 };
1867
1868 #define PMU_EVENT_ATTR_ID(_name, _show, _id) \
1869 (&((struct perf_pmu_events_attr[]) { \
1870 { .attr = __ATTR(_name, 0444, _show, NULL), \
1871 .id = _id, } \
1872 })[0].attr.attr)
1873
1874 #define PMU_FORMAT_ATTR_SHOW(_name, _format) \
1875 static ssize_t \
1876 _name##_show(struct device *dev, \
1877 struct device_attribute *attr, \
1878 char *page) \
1879 { \
1880 BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE); \
1881 return sprintf(page, _format "\n"); \
1882 } \
1883
1884 #define PMU_FORMAT_ATTR(_name, _format) \
1885 PMU_FORMAT_ATTR_SHOW(_name, _format) \
1886 \
1887 static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
1888
1889 /* Performance counter hotplug functions */
1890 #ifdef CONFIG_PERF_EVENTS
1891 int perf_event_init_cpu(unsigned int cpu);
1892 int perf_event_exit_cpu(unsigned int cpu);
1893 #else
1894 #define perf_event_init_cpu NULL
1895 #define perf_event_exit_cpu NULL
1896 #endif
1897
1898 extern void arch_perf_update_userpage(struct perf_event *event,
1899 struct perf_event_mmap_page *userpg,
1900 u64 now);
1901
1902 /*
1903 * Snapshot branch stack on software events.
1904 *
1905 * Branch stack can be very useful in understanding software events. For
1906 * example, when a long function, e.g. sys_perf_event_open, returns an
1907 * errno, it is not obvious why the function failed. Branch stack could
1908 * provide very helpful information in this type of scenarios.
1909 *
1910 * On software event, it is necessary to stop the hardware branch recorder
1911 * fast. Otherwise, the hardware register/buffer will be flushed with
1912 * entries of the triggering event. Therefore, static call is used to
1913 * stop the hardware recorder.
1914 */
1915
1916 /*
1917 * cnt is the number of entries allocated for entries.
1918 * Return number of entries copied to .
1919 */
1920 typedef int (perf_snapshot_branch_stack_t)(struct perf_branch_entry *entries,
1921 unsigned int cnt);
1922 DECLARE_STATIC_CALL(perf_snapshot_branch_stack, perf_snapshot_branch_stack_t);
1923
1924 #ifndef PERF_NEEDS_LOPWR_CB
perf_lopwr_cb(bool mode)1925 static inline void perf_lopwr_cb(bool mode)
1926 {
1927 }
1928 #endif
1929
1930 #endif /* _LINUX_PERF_EVENT_H */
1931