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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
29struct perf_guest_info_callbacks {
30 int (*is_in_guest)(void);
31 int (*is_user_mode)(void);
32 unsigned long (*get_guest_ip)(void);
33 void (*handle_intel_pt_intr)(void);
34};
35
36#ifdef CONFIG_HAVE_HW_BREAKPOINT
37#include <asm/hw_breakpoint.h>
38#endif
39
40#include <linux/list.h>
41#include <linux/mutex.h>
42#include <linux/rculist.h>
43#include <linux/rcupdate.h>
44#include <linux/spinlock.h>
45#include <linux/hrtimer.h>
46#include <linux/fs.h>
47#include <linux/pid_namespace.h>
48#include <linux/workqueue.h>
49#include <linux/ftrace.h>
50#include <linux/cpu.h>
51#include <linux/irq_work.h>
52#include <linux/static_key.h>
53#include <linux/jump_label_ratelimit.h>
54#include <linux/atomic.h>
55#include <linux/sysfs.h>
56#include <linux/perf_regs.h>
57#include <linux/cgroup.h>
58#include <linux/refcount.h>
59#include <asm/local.h>
60
61struct perf_callchain_entry {
62 __u64 nr;
63 __u64 ip[0]; /* /proc/sys/kernel/perf_event_max_stack */
64};
65
66struct perf_callchain_entry_ctx {
67 struct perf_callchain_entry *entry;
68 u32 max_stack;
69 u32 nr;
70 short contexts;
71 bool contexts_maxed;
72};
73
74typedef unsigned long (*perf_copy_f)(void *dst, const void *src,
75 unsigned long off, unsigned long len);
76
77struct perf_raw_frag {
78 union {
79 struct perf_raw_frag *next;
80 unsigned long pad;
81 };
82 perf_copy_f copy;
83 void *data;
84 u32 size;
85} __packed;
86
87struct perf_raw_record {
88 struct perf_raw_frag frag;
89 u32 size;
90};
91
92/*
93 * branch stack layout:
94 * nr: number of taken branches stored in entries[]
95 *
96 * Note that nr can vary from sample to sample
97 * branches (to, from) are stored from most recent
98 * to least recent, i.e., entries[0] contains the most
99 * recent branch.
100 */
101struct perf_branch_stack {
102 __u64 nr;
103 struct perf_branch_entry entries[0];
104};
105
106struct task_struct;
107
108/*
109 * extra PMU register associated with an event
110 */
111struct hw_perf_event_extra {
112 u64 config; /* register value */
113 unsigned int reg; /* register address or index */
114 int alloc; /* extra register already allocated */
115 int idx; /* index in shared_regs->regs[] */
116};
117
118/**
119 * struct hw_perf_event - performance event hardware details:
120 */
121struct hw_perf_event {
122#ifdef CONFIG_PERF_EVENTS
123 union {
124 struct { /* hardware */
125 u64 config;
126 u64 last_tag;
127 unsigned long config_base;
128 unsigned long event_base;
129 int event_base_rdpmc;
130 int idx;
131 int last_cpu;
132 int flags;
133
134 struct hw_perf_event_extra extra_reg;
135 struct hw_perf_event_extra branch_reg;
136 };
137 struct { /* software */
138 struct hrtimer hrtimer;
139 };
140 struct { /* tracepoint */
141 /* for tp_event->class */
142 struct list_head tp_list;
143 };
144 struct { /* amd_power */
145 u64 pwr_acc;
146 u64 ptsc;
147 };
148#ifdef CONFIG_HAVE_HW_BREAKPOINT
149 struct { /* breakpoint */
150 /*
151 * Crufty hack to avoid the chicken and egg
152 * problem hw_breakpoint has with context
153 * creation and event initalization.
154 */
155 struct arch_hw_breakpoint info;
156 struct list_head bp_list;
157 };
158#endif
159 struct { /* amd_iommu */
160 u8 iommu_bank;
161 u8 iommu_cntr;
162 u16 padding;
163 u64 conf;
164 u64 conf1;
165 };
166 };
167 /*
168 * If the event is a per task event, this will point to the task in
169 * question. See the comment in perf_event_alloc().
170 */
171 struct task_struct *target;
172
173 /*
174 * PMU would store hardware filter configuration
175 * here.
176 */
177 void *addr_filters;
178
179 /* Last sync'ed generation of filters */
180 unsigned long addr_filters_gen;
181
182/*
183 * hw_perf_event::state flags; used to track the PERF_EF_* state.
184 */
185#define PERF_HES_STOPPED 0x01 /* the counter is stopped */
186#define PERF_HES_UPTODATE 0x02 /* event->count up-to-date */
187#define PERF_HES_ARCH 0x04
188
189 int state;
190
191 /*
192 * The last observed hardware counter value, updated with a
193 * local64_cmpxchg() such that pmu::read() can be called nested.
194 */
195 local64_t prev_count;
196
197 /*
198 * The period to start the next sample with.
199 */
200 u64 sample_period;
201
202 /*
203 * The period we started this sample with.
204 */
205 u64 last_period;
206
207 /*
208 * However much is left of the current period; note that this is
209 * a full 64bit value and allows for generation of periods longer
210 * than hardware might allow.
211 */
212 local64_t period_left;
213
214 /*
215 * State for throttling the event, see __perf_event_overflow() and
216 * perf_adjust_freq_unthr_context().
217 */
218 u64 interrupts_seq;
219 u64 interrupts;
220
221 /*
222 * State for freq target events, see __perf_event_overflow() and
223 * perf_adjust_freq_unthr_context().
224 */
225 u64 freq_time_stamp;
226 u64 freq_count_stamp;
227#endif
228};
229
230struct perf_event;
231
232/*
233 * Common implementation detail of pmu::{start,commit,cancel}_txn
234 */
235#define PERF_PMU_TXN_ADD 0x1 /* txn to add/schedule event on PMU */
236#define PERF_PMU_TXN_READ 0x2 /* txn to read event group from PMU */
237
238/**
239 * pmu::capabilities flags
240 */
241#define PERF_PMU_CAP_NO_INTERRUPT 0x01
242#define PERF_PMU_CAP_NO_NMI 0x02
243#define PERF_PMU_CAP_AUX_NO_SG 0x04
244#define PERF_PMU_CAP_EXTENDED_REGS 0x08
245#define PERF_PMU_CAP_EXCLUSIVE 0x10
246#define PERF_PMU_CAP_ITRACE 0x20
247#define PERF_PMU_CAP_HETEROGENEOUS_CPUS 0x40
248#define PERF_PMU_CAP_NO_EXCLUDE 0x80
249
250/**
251 * struct pmu - generic performance monitoring unit
252 */
253struct pmu {
254 struct list_head entry;
255
256 struct module *module;
257 struct device *dev;
258 const struct attribute_group **attr_groups;
259 const char *name;
260 int type;
261
262 /*
263 * various common per-pmu feature flags
264 */
265 int capabilities;
266
267 int __percpu *pmu_disable_count;
268 struct perf_cpu_context __percpu *pmu_cpu_context;
269 atomic_t exclusive_cnt; /* < 0: cpu; > 0: tsk */
270 int task_ctx_nr;
271 int hrtimer_interval_ms;
272
273 /* number of address filters this PMU can do */
274 unsigned int nr_addr_filters;
275
276 /*
277 * Fully disable/enable this PMU, can be used to protect from the PMI
278 * as well as for lazy/batch writing of the MSRs.
279 */
280 void (*pmu_enable) (struct pmu *pmu); /* optional */
281 void (*pmu_disable) (struct pmu *pmu); /* optional */
282
283 /*
284 * Try and initialize the event for this PMU.
285 *
286 * Returns:
287 * -ENOENT -- @event is not for this PMU
288 *
289 * -ENODEV -- @event is for this PMU but PMU not present
290 * -EBUSY -- @event is for this PMU but PMU temporarily unavailable
291 * -EINVAL -- @event is for this PMU but @event is not valid
292 * -EOPNOTSUPP -- @event is for this PMU, @event is valid, but not supported
293 * -EACCESS -- @event is for this PMU, @event is valid, but no privilidges
294 *
295 * 0 -- @event is for this PMU and valid
296 *
297 * Other error return values are allowed.
298 */
299 int (*event_init) (struct perf_event *event);
300
301 /*
302 * Notification that the event was mapped or unmapped. Called
303 * in the context of the mapping task.
304 */
305 void (*event_mapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
306 void (*event_unmapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
307
308 /*
309 * Flags for ->add()/->del()/ ->start()/->stop(). There are
310 * matching hw_perf_event::state flags.
311 */
312#define PERF_EF_START 0x01 /* start the counter when adding */
313#define PERF_EF_RELOAD 0x02 /* reload the counter when starting */
314#define PERF_EF_UPDATE 0x04 /* update the counter when stopping */
315
316 /*
317 * Adds/Removes a counter to/from the PMU, can be done inside a
318 * transaction, see the ->*_txn() methods.
319 *
320 * The add/del callbacks will reserve all hardware resources required
321 * to service the event, this includes any counter constraint
322 * scheduling etc.
323 *
324 * Called with IRQs disabled and the PMU disabled on the CPU the event
325 * is on.
326 *
327 * ->add() called without PERF_EF_START should result in the same state
328 * as ->add() followed by ->stop().
329 *
330 * ->del() must always PERF_EF_UPDATE stop an event. If it calls
331 * ->stop() that must deal with already being stopped without
332 * PERF_EF_UPDATE.
333 */
334 int (*add) (struct perf_event *event, int flags);
335 void (*del) (struct perf_event *event, int flags);
336
337 /*
338 * Starts/Stops a counter present on the PMU.
339 *
340 * The PMI handler should stop the counter when perf_event_overflow()
341 * returns !0. ->start() will be used to continue.
342 *
343 * Also used to change the sample period.
344 *
345 * Called with IRQs disabled and the PMU disabled on the CPU the event
346 * is on -- will be called from NMI context with the PMU generates
347 * NMIs.
348 *
349 * ->stop() with PERF_EF_UPDATE will read the counter and update
350 * period/count values like ->read() would.
351 *
352 * ->start() with PERF_EF_RELOAD will reprogram the the counter
353 * value, must be preceded by a ->stop() with PERF_EF_UPDATE.
354 */
355 void (*start) (struct perf_event *event, int flags);
356 void (*stop) (struct perf_event *event, int flags);
357
358 /*
359 * Updates the counter value of the event.
360 *
361 * For sampling capable PMUs this will also update the software period
362 * hw_perf_event::period_left field.
363 */
364 void (*read) (struct perf_event *event);
365
366 /*
367 * Group events scheduling is treated as a transaction, add
368 * group events as a whole and perform one schedulability test.
369 * If the test fails, roll back the whole group
370 *
371 * Start the transaction, after this ->add() doesn't need to
372 * do schedulability tests.
373 *
374 * Optional.
375 */
376 void (*start_txn) (struct pmu *pmu, unsigned int txn_flags);
377 /*
378 * If ->start_txn() disabled the ->add() schedulability test
379 * then ->commit_txn() is required to perform one. On success
380 * the transaction is closed. On error the transaction is kept
381 * open until ->cancel_txn() is called.
382 *
383 * Optional.
384 */
385 int (*commit_txn) (struct pmu *pmu);
386 /*
387 * Will cancel the transaction, assumes ->del() is called
388 * for each successful ->add() during the transaction.
389 *
390 * Optional.
391 */
392 void (*cancel_txn) (struct pmu *pmu);
393
394 /*
395 * Will return the value for perf_event_mmap_page::index for this event,
396 * if no implementation is provided it will default to: event->hw.idx + 1.
397 */
398 int (*event_idx) (struct perf_event *event); /*optional */
399
400 /*
401 * context-switches callback
402 */
403 void (*sched_task) (struct perf_event_context *ctx,
404 bool sched_in);
405 /*
406 * PMU specific data size
407 */
408 size_t task_ctx_size;
409
410
411 /*
412 * Set up pmu-private data structures for an AUX area
413 */
414 void *(*setup_aux) (struct perf_event *event, void **pages,
415 int nr_pages, bool overwrite);
416 /* optional */
417
418 /*
419 * Free pmu-private AUX data structures
420 */
421 void (*free_aux) (void *aux); /* optional */
422
423 /*
424 * Validate address range filters: make sure the HW supports the
425 * requested configuration and number of filters; return 0 if the
426 * supplied filters are valid, -errno otherwise.
427 *
428 * Runs in the context of the ioctl()ing process and is not serialized
429 * with the rest of the PMU callbacks.
430 */
431 int (*addr_filters_validate) (struct list_head *filters);
432 /* optional */
433
434 /*
435 * Synchronize address range filter configuration:
436 * translate hw-agnostic filters into hardware configuration in
437 * event::hw::addr_filters.
438 *
439 * Runs as a part of filter sync sequence that is done in ->start()
440 * callback by calling perf_event_addr_filters_sync().
441 *
442 * May (and should) traverse event::addr_filters::list, for which its
443 * caller provides necessary serialization.
444 */
445 void (*addr_filters_sync) (struct perf_event *event);
446 /* optional */
447
448 /*
449 * Filter events for PMU-specific reasons.
450 */
451 int (*filter_match) (struct perf_event *event); /* optional */
452
453 /*
454 * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
455 */
456 int (*check_period) (struct perf_event *event, u64 value); /* optional */
457};
458
459enum perf_addr_filter_action_t {
460 PERF_ADDR_FILTER_ACTION_STOP = 0,
461 PERF_ADDR_FILTER_ACTION_START,
462 PERF_ADDR_FILTER_ACTION_FILTER,
463};
464
465/**
466 * struct perf_addr_filter - address range filter definition
467 * @entry: event's filter list linkage
468 * @path: object file's path for file-based filters
469 * @offset: filter range offset
470 * @size: filter range size (size==0 means single address trigger)
471 * @action: filter/start/stop
472 *
473 * This is a hardware-agnostic filter configuration as specified by the user.
474 */
475struct perf_addr_filter {
476 struct list_head entry;
477 struct path path;
478 unsigned long offset;
479 unsigned long size;
480 enum perf_addr_filter_action_t action;
481};
482
483/**
484 * struct perf_addr_filters_head - container for address range filters
485 * @list: list of filters for this event
486 * @lock: spinlock that serializes accesses to the @list and event's
487 * (and its children's) filter generations.
488 * @nr_file_filters: number of file-based filters
489 *
490 * A child event will use parent's @list (and therefore @lock), so they are
491 * bundled together; see perf_event_addr_filters().
492 */
493struct perf_addr_filters_head {
494 struct list_head list;
495 raw_spinlock_t lock;
496 unsigned int nr_file_filters;
497};
498
499struct perf_addr_filter_range {
500 unsigned long start;
501 unsigned long size;
502};
503
504/**
505 * enum perf_event_state - the states of an event:
506 */
507enum perf_event_state {
508 PERF_EVENT_STATE_DEAD = -4,
509 PERF_EVENT_STATE_EXIT = -3,
510 PERF_EVENT_STATE_ERROR = -2,
511 PERF_EVENT_STATE_OFF = -1,
512 PERF_EVENT_STATE_INACTIVE = 0,
513 PERF_EVENT_STATE_ACTIVE = 1,
514};
515
516struct file;
517struct perf_sample_data;
518
519typedef void (*perf_overflow_handler_t)(struct perf_event *,
520 struct perf_sample_data *,
521 struct pt_regs *regs);
522
523/*
524 * Event capabilities. For event_caps and groups caps.
525 *
526 * PERF_EV_CAP_SOFTWARE: Is a software event.
527 * PERF_EV_CAP_READ_ACTIVE_PKG: A CPU event (or cgroup event) that can be read
528 * from any CPU in the package where it is active.
529 */
530#define PERF_EV_CAP_SOFTWARE BIT(0)
531#define PERF_EV_CAP_READ_ACTIVE_PKG BIT(1)
532
533#define SWEVENT_HLIST_BITS 8
534#define SWEVENT_HLIST_SIZE (1 << SWEVENT_HLIST_BITS)
535
536struct swevent_hlist {
537 struct hlist_head heads[SWEVENT_HLIST_SIZE];
538 struct rcu_head rcu_head;
539};
540
541#define PERF_ATTACH_CONTEXT 0x01
542#define PERF_ATTACH_GROUP 0x02
543#define PERF_ATTACH_TASK 0x04
544#define PERF_ATTACH_TASK_DATA 0x08
545#define PERF_ATTACH_ITRACE 0x10
546
547struct perf_cgroup;
548struct ring_buffer;
549
550struct pmu_event_list {
551 raw_spinlock_t lock;
552 struct list_head list;
553};
554
555#define for_each_sibling_event(sibling, event) \
556 if ((event)->group_leader == (event)) \
557 list_for_each_entry((sibling), &(event)->sibling_list, sibling_list)
558
559/**
560 * struct perf_event - performance event kernel representation:
561 */
562struct perf_event {
563#ifdef CONFIG_PERF_EVENTS
564 /*
565 * entry onto perf_event_context::event_list;
566 * modifications require ctx->lock
567 * RCU safe iterations.
568 */
569 struct list_head event_entry;
570
571 /*
572 * Locked for modification by both ctx->mutex and ctx->lock; holding
573 * either sufficies for read.
574 */
575 struct list_head sibling_list;
576 struct list_head active_list;
577 /*
578 * Node on the pinned or flexible tree located at the event context;
579 */
580 struct rb_node group_node;
581 u64 group_index;
582 /*
583 * We need storage to track the entries in perf_pmu_migrate_context; we
584 * cannot use the event_entry because of RCU and we want to keep the
585 * group in tact which avoids us using the other two entries.
586 */
587 struct list_head migrate_entry;
588
589 struct hlist_node hlist_entry;
590 struct list_head active_entry;
591 int nr_siblings;
592
593 /* Not serialized. Only written during event initialization. */
594 int event_caps;
595 /* The cumulative AND of all event_caps for events in this group. */
596 int group_caps;
597
598 struct perf_event *group_leader;
599 struct pmu *pmu;
600 void *pmu_private;
601
602 enum perf_event_state state;
603 unsigned int attach_state;
604 local64_t count;
605 atomic64_t child_count;
606
607 /*
608 * These are the total time in nanoseconds that the event
609 * has been enabled (i.e. eligible to run, and the task has
610 * been scheduled in, if this is a per-task event)
611 * and running (scheduled onto the CPU), respectively.
612 */
613 u64 total_time_enabled;
614 u64 total_time_running;
615 u64 tstamp;
616
617 /*
618 * timestamp shadows the actual context timing but it can
619 * be safely used in NMI interrupt context. It reflects the
620 * context time as it was when the event was last scheduled in.
621 *
622 * ctx_time already accounts for ctx->timestamp. Therefore to
623 * compute ctx_time for a sample, simply add perf_clock().
624 */
625 u64 shadow_ctx_time;
626
627 struct perf_event_attr attr;
628 u16 header_size;
629 u16 id_header_size;
630 u16 read_size;
631 struct hw_perf_event hw;
632
633 struct perf_event_context *ctx;
634 atomic_long_t refcount;
635
636 /*
637 * These accumulate total time (in nanoseconds) that children
638 * events have been enabled and running, respectively.
639 */
640 atomic64_t child_total_time_enabled;
641 atomic64_t child_total_time_running;
642
643 /*
644 * Protect attach/detach and child_list:
645 */
646 struct mutex child_mutex;
647 struct list_head child_list;
648 struct perf_event *parent;
649
650 int oncpu;
651 int cpu;
652
653 struct list_head owner_entry;
654 struct task_struct *owner;
655
656 /* mmap bits */
657 struct mutex mmap_mutex;
658 atomic_t mmap_count;
659
660 struct ring_buffer *rb;
661 struct list_head rb_entry;
662 unsigned long rcu_batches;
663 int rcu_pending;
664
665 /* poll related */
666 wait_queue_head_t waitq;
667 struct fasync_struct *fasync;
668
669 /* delayed work for NMIs and such */
670 int pending_wakeup;
671 int pending_kill;
672 int pending_disable;
673 struct irq_work pending;
674
675 atomic_t event_limit;
676
677 /* address range filters */
678 struct perf_addr_filters_head addr_filters;
679 /* vma address array for file-based filders */
680 struct perf_addr_filter_range *addr_filter_ranges;
681 unsigned long addr_filters_gen;
682
683 void (*destroy)(struct perf_event *);
684 struct rcu_head rcu_head;
685
686 struct pid_namespace *ns;
687 u64 id;
688
689 u64 (*clock)(void);
690 perf_overflow_handler_t overflow_handler;
691 void *overflow_handler_context;
692#ifdef CONFIG_BPF_SYSCALL
693 perf_overflow_handler_t orig_overflow_handler;
694 struct bpf_prog *prog;
695#endif
696
697#ifdef CONFIG_EVENT_TRACING
698 struct trace_event_call *tp_event;
699 struct event_filter *filter;
700#ifdef CONFIG_FUNCTION_TRACER
701 struct ftrace_ops ftrace_ops;
702#endif
703#endif
704
705#ifdef CONFIG_CGROUP_PERF
706 struct perf_cgroup *cgrp; /* cgroup event is attach to */
707#endif
708
709 struct list_head sb_list;
710#endif /* CONFIG_PERF_EVENTS */
711};
712
713
714struct perf_event_groups {
715 struct rb_root tree;
716 u64 index;
717};
718
719/**
720 * struct perf_event_context - event context structure
721 *
722 * Used as a container for task events and CPU events as well:
723 */
724struct perf_event_context {
725 struct pmu *pmu;
726 /*
727 * Protect the states of the events in the list,
728 * nr_active, and the list:
729 */
730 raw_spinlock_t lock;
731 /*
732 * Protect the list of events. Locking either mutex or lock
733 * is sufficient to ensure the list doesn't change; to change
734 * the list you need to lock both the mutex and the spinlock.
735 */
736 struct mutex mutex;
737
738 struct list_head active_ctx_list;
739 struct perf_event_groups pinned_groups;
740 struct perf_event_groups flexible_groups;
741 struct list_head event_list;
742
743 struct list_head pinned_active;
744 struct list_head flexible_active;
745
746 int nr_events;
747 int nr_active;
748 int is_active;
749 int nr_stat;
750 int nr_freq;
751 int rotate_disable;
752 refcount_t refcount;
753 struct task_struct *task;
754
755 /*
756 * Context clock, runs when context enabled.
757 */
758 u64 time;
759 u64 timestamp;
760
761 /*
762 * These fields let us detect when two contexts have both
763 * been cloned (inherited) from a common ancestor.
764 */
765 struct perf_event_context *parent_ctx;
766 u64 parent_gen;
767 u64 generation;
768 int pin_count;
769#ifdef CONFIG_CGROUP_PERF
770 int nr_cgroups; /* cgroup evts */
771#endif
772 void *task_ctx_data; /* pmu specific data */
773 struct rcu_head rcu_head;
774};
775
776/*
777 * Number of contexts where an event can trigger:
778 * task, softirq, hardirq, nmi.
779 */
780#define PERF_NR_CONTEXTS 4
781
782/**
783 * struct perf_event_cpu_context - per cpu event context structure
784 */
785struct perf_cpu_context {
786 struct perf_event_context ctx;
787 struct perf_event_context *task_ctx;
788 int active_oncpu;
789 int exclusive;
790
791 raw_spinlock_t hrtimer_lock;
792 struct hrtimer hrtimer;
793 ktime_t hrtimer_interval;
794 unsigned int hrtimer_active;
795
796#ifdef CONFIG_CGROUP_PERF
797 struct perf_cgroup *cgrp;
798 struct list_head cgrp_cpuctx_entry;
799#endif
800
801 struct list_head sched_cb_entry;
802 int sched_cb_usage;
803
804 int online;
805};
806
807struct perf_output_handle {
808 struct perf_event *event;
809 struct ring_buffer *rb;
810 unsigned long wakeup;
811 unsigned long size;
812 u64 aux_flags;
813 union {
814 void *addr;
815 unsigned long head;
816 };
817 int page;
818};
819
820struct bpf_perf_event_data_kern {
821 bpf_user_pt_regs_t *regs;
822 struct perf_sample_data *data;
823 struct perf_event *event;
824};
825
826#ifdef CONFIG_CGROUP_PERF
827
828/*
829 * perf_cgroup_info keeps track of time_enabled for a cgroup.
830 * This is a per-cpu dynamically allocated data structure.
831 */
832struct perf_cgroup_info {
833 u64 time;
834 u64 timestamp;
835};
836
837struct perf_cgroup {
838 struct cgroup_subsys_state css;
839 struct perf_cgroup_info __percpu *info;
840};
841
842/*
843 * Must ensure cgroup is pinned (css_get) before calling
844 * this function. In other words, we cannot call this function
845 * if there is no cgroup event for the current CPU context.
846 */
847static inline struct perf_cgroup *
848perf_cgroup_from_task(struct task_struct *task, struct perf_event_context *ctx)
849{
850 return container_of(task_css_check(task, perf_event_cgrp_id,
851 ctx ? lockdep_is_held(&ctx->lock)
852 : true),
853 struct perf_cgroup, css);
854}
855#endif /* CONFIG_CGROUP_PERF */
856
857#ifdef CONFIG_PERF_EVENTS
858
859extern void *perf_aux_output_begin(struct perf_output_handle *handle,
860 struct perf_event *event);
861extern void perf_aux_output_end(struct perf_output_handle *handle,
862 unsigned long size);
863extern int perf_aux_output_skip(struct perf_output_handle *handle,
864 unsigned long size);
865extern void *perf_get_aux(struct perf_output_handle *handle);
866extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
867extern void perf_event_itrace_started(struct perf_event *event);
868
869extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
870extern void perf_pmu_unregister(struct pmu *pmu);
871
872extern int perf_num_counters(void);
873extern const char *perf_pmu_name(void);
874extern void __perf_event_task_sched_in(struct task_struct *prev,
875 struct task_struct *task);
876extern void __perf_event_task_sched_out(struct task_struct *prev,
877 struct task_struct *next);
878extern int perf_event_init_task(struct task_struct *child);
879extern void perf_event_exit_task(struct task_struct *child);
880extern void perf_event_free_task(struct task_struct *task);
881extern void perf_event_delayed_put(struct task_struct *task);
882extern struct file *perf_event_get(unsigned int fd);
883extern const struct perf_event *perf_get_event(struct file *file);
884extern const struct perf_event_attr *perf_event_attrs(struct perf_event *event);
885extern void perf_event_print_debug(void);
886extern void perf_pmu_disable(struct pmu *pmu);
887extern void perf_pmu_enable(struct pmu *pmu);
888extern void perf_sched_cb_dec(struct pmu *pmu);
889extern void perf_sched_cb_inc(struct pmu *pmu);
890extern int perf_event_task_disable(void);
891extern int perf_event_task_enable(void);
892
893extern void perf_pmu_resched(struct pmu *pmu);
894
895extern int perf_event_refresh(struct perf_event *event, int refresh);
896extern void perf_event_update_userpage(struct perf_event *event);
897extern int perf_event_release_kernel(struct perf_event *event);
898extern struct perf_event *
899perf_event_create_kernel_counter(struct perf_event_attr *attr,
900 int cpu,
901 struct task_struct *task,
902 perf_overflow_handler_t callback,
903 void *context);
904extern void perf_pmu_migrate_context(struct pmu *pmu,
905 int src_cpu, int dst_cpu);
906int perf_event_read_local(struct perf_event *event, u64 *value,
907 u64 *enabled, u64 *running);
908extern u64 perf_event_read_value(struct perf_event *event,
909 u64 *enabled, u64 *running);
910
911
912struct perf_sample_data {
913 /*
914 * Fields set by perf_sample_data_init(), group so as to
915 * minimize the cachelines touched.
916 */
917 u64 addr;
918 struct perf_raw_record *raw;
919 struct perf_branch_stack *br_stack;
920 u64 period;
921 u64 weight;
922 u64 txn;
923 union perf_mem_data_src data_src;
924
925 /*
926 * The other fields, optionally {set,used} by
927 * perf_{prepare,output}_sample().
928 */
929 u64 type;
930 u64 ip;
931 struct {
932 u32 pid;
933 u32 tid;
934 } tid_entry;
935 u64 time;
936 u64 id;
937 u64 stream_id;
938 struct {
939 u32 cpu;
940 u32 reserved;
941 } cpu_entry;
942 struct perf_callchain_entry *callchain;
943
944 /*
945 * regs_user may point to task_pt_regs or to regs_user_copy, depending
946 * on arch details.
947 */
948 struct perf_regs regs_user;
949 struct pt_regs regs_user_copy;
950
951 struct perf_regs regs_intr;
952 u64 stack_user_size;
953
954 u64 phys_addr;
955} ____cacheline_aligned;
956
957/* default value for data source */
958#define PERF_MEM_NA (PERF_MEM_S(OP, NA) |\
959 PERF_MEM_S(LVL, NA) |\
960 PERF_MEM_S(SNOOP, NA) |\
961 PERF_MEM_S(LOCK, NA) |\
962 PERF_MEM_S(TLB, NA))
963
964static inline void perf_sample_data_init(struct perf_sample_data *data,
965 u64 addr, u64 period)
966{
967 /* remaining struct members initialized in perf_prepare_sample() */
968 data->addr = addr;
969 data->raw = NULL;
970 data->br_stack = NULL;
971 data->period = period;
972 data->weight = 0;
973 data->data_src.val = PERF_MEM_NA;
974 data->txn = 0;
975}
976
977extern void perf_output_sample(struct perf_output_handle *handle,
978 struct perf_event_header *header,
979 struct perf_sample_data *data,
980 struct perf_event *event);
981extern void perf_prepare_sample(struct perf_event_header *header,
982 struct perf_sample_data *data,
983 struct perf_event *event,
984 struct pt_regs *regs);
985
986extern int perf_event_overflow(struct perf_event *event,
987 struct perf_sample_data *data,
988 struct pt_regs *regs);
989
990extern void perf_event_output_forward(struct perf_event *event,
991 struct perf_sample_data *data,
992 struct pt_regs *regs);
993extern void perf_event_output_backward(struct perf_event *event,
994 struct perf_sample_data *data,
995 struct pt_regs *regs);
996extern int perf_event_output(struct perf_event *event,
997 struct perf_sample_data *data,
998 struct pt_regs *regs);
999
1000static inline bool
1001is_default_overflow_handler(struct perf_event *event)
1002{
1003 if (likely(event->overflow_handler == perf_event_output_forward))
1004 return true;
1005 if (unlikely(event->overflow_handler == perf_event_output_backward))
1006 return true;
1007 return false;
1008}
1009
1010extern void
1011perf_event_header__init_id(struct perf_event_header *header,
1012 struct perf_sample_data *data,
1013 struct perf_event *event);
1014extern void
1015perf_event__output_id_sample(struct perf_event *event,
1016 struct perf_output_handle *handle,
1017 struct perf_sample_data *sample);
1018
1019extern void
1020perf_log_lost_samples(struct perf_event *event, u64 lost);
1021
1022static inline bool event_has_any_exclude_flag(struct perf_event *event)
1023{
1024 struct perf_event_attr *attr = &event->attr;
1025
1026 return attr->exclude_idle || attr->exclude_user ||
1027 attr->exclude_kernel || attr->exclude_hv ||
1028 attr->exclude_guest || attr->exclude_host;
1029}
1030
1031static inline bool is_sampling_event(struct perf_event *event)
1032{
1033 return event->attr.sample_period != 0;
1034}
1035
1036/*
1037 * Return 1 for a software event, 0 for a hardware event
1038 */
1039static inline int is_software_event(struct perf_event *event)
1040{
1041 return event->event_caps & PERF_EV_CAP_SOFTWARE;
1042}
1043
1044/*
1045 * Return 1 for event in sw context, 0 for event in hw context
1046 */
1047static inline int in_software_context(struct perf_event *event)
1048{
1049 return event->ctx->pmu->task_ctx_nr == perf_sw_context;
1050}
1051
1052extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
1053
1054extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
1055extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
1056
1057#ifndef perf_arch_fetch_caller_regs
1058static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
1059#endif
1060
1061/*
1062 * When generating a perf sample in-line, instead of from an interrupt /
1063 * exception, we lack a pt_regs. This is typically used from software events
1064 * like: SW_CONTEXT_SWITCHES, SW_MIGRATIONS and the tie-in with tracepoints.
1065 *
1066 * We typically don't need a full set, but (for x86) do require:
1067 * - ip for PERF_SAMPLE_IP
1068 * - cs for user_mode() tests
1069 * - sp for PERF_SAMPLE_CALLCHAIN
1070 * - eflags for MISC bits and CALLCHAIN (see: perf_hw_regs())
1071 *
1072 * NOTE: assumes @regs is otherwise already 0 filled; this is important for
1073 * things like PERF_SAMPLE_REGS_INTR.
1074 */
1075static inline void perf_fetch_caller_regs(struct pt_regs *regs)
1076{
1077 perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
1078}
1079
1080static __always_inline void
1081perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
1082{
1083 if (static_key_false(&perf_swevent_enabled[event_id]))
1084 __perf_sw_event(event_id, nr, regs, addr);
1085}
1086
1087DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);
1088
1089/*
1090 * 'Special' version for the scheduler, it hard assumes no recursion,
1091 * which is guaranteed by us not actually scheduling inside other swevents
1092 * because those disable preemption.
1093 */
1094static __always_inline void
1095perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
1096{
1097 if (static_key_false(&perf_swevent_enabled[event_id])) {
1098 struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
1099
1100 perf_fetch_caller_regs(regs);
1101 ___perf_sw_event(event_id, nr, regs, addr);
1102 }
1103}
1104
1105extern struct static_key_false perf_sched_events;
1106
1107static __always_inline bool
1108perf_sw_migrate_enabled(void)
1109{
1110 if (static_key_false(&perf_swevent_enabled[PERF_COUNT_SW_CPU_MIGRATIONS]))
1111 return true;
1112 return false;
1113}
1114
1115static inline void perf_event_task_migrate(struct task_struct *task)
1116{
1117 if (perf_sw_migrate_enabled())
1118 task->sched_migrated = 1;
1119}
1120
1121static inline void perf_event_task_sched_in(struct task_struct *prev,
1122 struct task_struct *task)
1123{
1124 if (static_branch_unlikely(&perf_sched_events))
1125 __perf_event_task_sched_in(prev, task);
1126
1127 if (perf_sw_migrate_enabled() && task->sched_migrated) {
1128 struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
1129
1130 perf_fetch_caller_regs(regs);
1131 ___perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, regs, 0);
1132 task->sched_migrated = 0;
1133 }
1134}
1135
1136static inline void perf_event_task_sched_out(struct task_struct *prev,
1137 struct task_struct *next)
1138{
1139 perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);
1140
1141 if (static_branch_unlikely(&perf_sched_events))
1142 __perf_event_task_sched_out(prev, next);
1143}
1144
1145extern void perf_event_mmap(struct vm_area_struct *vma);
1146
1147extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1148 bool unregister, const char *sym);
1149extern void perf_event_bpf_event(struct bpf_prog *prog,
1150 enum perf_bpf_event_type type,
1151 u16 flags);
1152
1153extern struct perf_guest_info_callbacks *perf_guest_cbs;
1154extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
1155extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
1156
1157extern void perf_event_exec(void);
1158extern void perf_event_comm(struct task_struct *tsk, bool exec);
1159extern void perf_event_namespaces(struct task_struct *tsk);
1160extern void perf_event_fork(struct task_struct *tsk);
1161
1162/* Callchains */
1163DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
1164
1165extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1166extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1167extern struct perf_callchain_entry *
1168get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
1169 u32 max_stack, bool crosstask, bool add_mark);
1170extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, struct pt_regs *regs);
1171extern int get_callchain_buffers(int max_stack);
1172extern void put_callchain_buffers(void);
1173
1174extern int sysctl_perf_event_max_stack;
1175extern int sysctl_perf_event_max_contexts_per_stack;
1176
1177static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
1178{
1179 if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
1180 struct perf_callchain_entry *entry = ctx->entry;
1181 entry->ip[entry->nr++] = ip;
1182 ++ctx->contexts;
1183 return 0;
1184 } else {
1185 ctx->contexts_maxed = true;
1186 return -1; /* no more room, stop walking the stack */
1187 }
1188}
1189
1190static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
1191{
1192 if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
1193 struct perf_callchain_entry *entry = ctx->entry;
1194 entry->ip[entry->nr++] = ip;
1195 ++ctx->nr;
1196 return 0;
1197 } else {
1198 return -1; /* no more room, stop walking the stack */
1199 }
1200}
1201
1202extern int sysctl_perf_event_paranoid;
1203extern int sysctl_perf_event_mlock;
1204extern int sysctl_perf_event_sample_rate;
1205extern int sysctl_perf_cpu_time_max_percent;
1206
1207extern void perf_sample_event_took(u64 sample_len_ns);
1208
1209extern int perf_proc_update_handler(struct ctl_table *table, int write,
1210 void __user *buffer, size_t *lenp,
1211 loff_t *ppos);
1212extern int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
1213 void __user *buffer, size_t *lenp,
1214 loff_t *ppos);
1215
1216int perf_event_max_stack_handler(struct ctl_table *table, int write,
1217 void __user *buffer, size_t *lenp, loff_t *ppos);
1218
1219static inline bool perf_paranoid_tracepoint_raw(void)
1220{
1221 return sysctl_perf_event_paranoid > -1;
1222}
1223
1224static inline bool perf_paranoid_cpu(void)
1225{
1226 return sysctl_perf_event_paranoid > 0;
1227}
1228
1229static inline bool perf_paranoid_kernel(void)
1230{
1231 return sysctl_perf_event_paranoid > 1;
1232}
1233
1234extern void perf_event_init(void);
1235extern void perf_tp_event(u16 event_type, u64 count, void *record,
1236 int entry_size, struct pt_regs *regs,
1237 struct hlist_head *head, int rctx,
1238 struct task_struct *task);
1239extern void perf_bp_event(struct perf_event *event, void *data);
1240
1241#ifndef perf_misc_flags
1242# define perf_misc_flags(regs) \
1243 (user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
1244# define perf_instruction_pointer(regs) instruction_pointer(regs)
1245#endif
1246#ifndef perf_arch_bpf_user_pt_regs
1247# define perf_arch_bpf_user_pt_regs(regs) regs
1248#endif
1249
1250static inline bool has_branch_stack(struct perf_event *event)
1251{
1252 return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
1253}
1254
1255static inline bool needs_branch_stack(struct perf_event *event)
1256{
1257 return event->attr.branch_sample_type != 0;
1258}
1259
1260static inline bool has_aux(struct perf_event *event)
1261{
1262 return event->pmu->setup_aux;
1263}
1264
1265static inline bool is_write_backward(struct perf_event *event)
1266{
1267 return !!event->attr.write_backward;
1268}
1269
1270static inline bool has_addr_filter(struct perf_event *event)
1271{
1272 return event->pmu->nr_addr_filters;
1273}
1274
1275/*
1276 * An inherited event uses parent's filters
1277 */
1278static inline struct perf_addr_filters_head *
1279perf_event_addr_filters(struct perf_event *event)
1280{
1281 struct perf_addr_filters_head *ifh = &event->addr_filters;
1282
1283 if (event->parent)
1284 ifh = &event->parent->addr_filters;
1285
1286 return ifh;
1287}
1288
1289extern void perf_event_addr_filters_sync(struct perf_event *event);
1290
1291extern int perf_output_begin(struct perf_output_handle *handle,
1292 struct perf_event *event, unsigned int size);
1293extern int perf_output_begin_forward(struct perf_output_handle *handle,
1294 struct perf_event *event,
1295 unsigned int size);
1296extern int perf_output_begin_backward(struct perf_output_handle *handle,
1297 struct perf_event *event,
1298 unsigned int size);
1299
1300extern void perf_output_end(struct perf_output_handle *handle);
1301extern unsigned int perf_output_copy(struct perf_output_handle *handle,
1302 const void *buf, unsigned int len);
1303extern unsigned int perf_output_skip(struct perf_output_handle *handle,
1304 unsigned int len);
1305extern int perf_swevent_get_recursion_context(void);
1306extern void perf_swevent_put_recursion_context(int rctx);
1307extern u64 perf_swevent_set_period(struct perf_event *event);
1308extern void perf_event_enable(struct perf_event *event);
1309extern void perf_event_disable(struct perf_event *event);
1310extern void perf_event_disable_local(struct perf_event *event);
1311extern void perf_event_disable_inatomic(struct perf_event *event);
1312extern void perf_event_task_tick(void);
1313extern int perf_event_account_interrupt(struct perf_event *event);
1314#else /* !CONFIG_PERF_EVENTS: */
1315static inline void *
1316perf_aux_output_begin(struct perf_output_handle *handle,
1317 struct perf_event *event) { return NULL; }
1318static inline void
1319perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
1320 { }
1321static inline int
1322perf_aux_output_skip(struct perf_output_handle *handle,
1323 unsigned long size) { return -EINVAL; }
1324static inline void *
1325perf_get_aux(struct perf_output_handle *handle) { return NULL; }
1326static inline void
1327perf_event_task_migrate(struct task_struct *task) { }
1328static inline void
1329perf_event_task_sched_in(struct task_struct *prev,
1330 struct task_struct *task) { }
1331static inline void
1332perf_event_task_sched_out(struct task_struct *prev,
1333 struct task_struct *next) { }
1334static inline int perf_event_init_task(struct task_struct *child) { return 0; }
1335static inline void perf_event_exit_task(struct task_struct *child) { }
1336static inline void perf_event_free_task(struct task_struct *task) { }
1337static inline void perf_event_delayed_put(struct task_struct *task) { }
1338static inline struct file *perf_event_get(unsigned int fd) { return ERR_PTR(-EINVAL); }
1339static inline const struct perf_event *perf_get_event(struct file *file)
1340{
1341 return ERR_PTR(-EINVAL);
1342}
1343static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
1344{
1345 return ERR_PTR(-EINVAL);
1346}
1347static inline int perf_event_read_local(struct perf_event *event, u64 *value,
1348 u64 *enabled, u64 *running)
1349{
1350 return -EINVAL;
1351}
1352static inline void perf_event_print_debug(void) { }
1353static inline int perf_event_task_disable(void) { return -EINVAL; }
1354static inline int perf_event_task_enable(void) { return -EINVAL; }
1355static inline int perf_event_refresh(struct perf_event *event, int refresh)
1356{
1357 return -EINVAL;
1358}
1359
1360static inline void
1361perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) { }
1362static inline void
1363perf_sw_event_sched(u32 event_id, u64 nr, u64 addr) { }
1364static inline void
1365perf_bp_event(struct perf_event *event, void *data) { }
1366
1367static inline int perf_register_guest_info_callbacks
1368(struct perf_guest_info_callbacks *callbacks) { return 0; }
1369static inline int perf_unregister_guest_info_callbacks
1370(struct perf_guest_info_callbacks *callbacks) { return 0; }
1371
1372static inline void perf_event_mmap(struct vm_area_struct *vma) { }
1373
1374typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data);
1375static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1376 bool unregister, const char *sym) { }
1377static inline void perf_event_bpf_event(struct bpf_prog *prog,
1378 enum perf_bpf_event_type type,
1379 u16 flags) { }
1380static inline void perf_event_exec(void) { }
1381static inline void perf_event_comm(struct task_struct *tsk, bool exec) { }
1382static inline void perf_event_namespaces(struct task_struct *tsk) { }
1383static inline void perf_event_fork(struct task_struct *tsk) { }
1384static inline void perf_event_init(void) { }
1385static inline int perf_swevent_get_recursion_context(void) { return -1; }
1386static inline void perf_swevent_put_recursion_context(int rctx) { }
1387static inline u64 perf_swevent_set_period(struct perf_event *event) { return 0; }
1388static inline void perf_event_enable(struct perf_event *event) { }
1389static inline void perf_event_disable(struct perf_event *event) { }
1390static inline int __perf_event_disable(void *info) { return -1; }
1391static inline void perf_event_task_tick(void) { }
1392static inline int perf_event_release_kernel(struct perf_event *event) { return 0; }
1393#endif
1394
1395#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
1396extern void perf_restore_debug_store(void);
1397#else
1398static inline void perf_restore_debug_store(void) { }
1399#endif
1400
1401static __always_inline bool perf_raw_frag_last(const struct perf_raw_frag *frag)
1402{
1403 return frag->pad < sizeof(u64);
1404}
1405
1406#define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
1407
1408struct perf_pmu_events_attr {
1409 struct device_attribute attr;
1410 u64 id;
1411 const char *event_str;
1412};
1413
1414struct perf_pmu_events_ht_attr {
1415 struct device_attribute attr;
1416 u64 id;
1417 const char *event_str_ht;
1418 const char *event_str_noht;
1419};
1420
1421ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
1422 char *page);
1423
1424#define PMU_EVENT_ATTR(_name, _var, _id, _show) \
1425static struct perf_pmu_events_attr _var = { \
1426 .attr = __ATTR(_name, 0444, _show, NULL), \
1427 .id = _id, \
1428};
1429
1430#define PMU_EVENT_ATTR_STRING(_name, _var, _str) \
1431static struct perf_pmu_events_attr _var = { \
1432 .attr = __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
1433 .id = 0, \
1434 .event_str = _str, \
1435};
1436
1437#define PMU_FORMAT_ATTR(_name, _format) \
1438static ssize_t \
1439_name##_show(struct device *dev, \
1440 struct device_attribute *attr, \
1441 char *page) \
1442{ \
1443 BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE); \
1444 return sprintf(page, _format "\n"); \
1445} \
1446 \
1447static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
1448
1449/* Performance counter hotplug functions */
1450#ifdef CONFIG_PERF_EVENTS
1451int perf_event_init_cpu(unsigned int cpu);
1452int perf_event_exit_cpu(unsigned int cpu);
1453#else
1454#define perf_event_init_cpu NULL
1455#define perf_event_exit_cpu NULL
1456#endif
1457
1458#endif /* _LINUX_PERF_EVENT_H */