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 
19 /*
20  * Kernel-internal data types and definitions:
21  */
22 
23 #ifdef CONFIG_PERF_EVENTS
24 # include <asm/perf_event.h>
25 # include <asm/local64.h>
26 #endif
27 
28 struct perf_guest_info_callbacks {
29 	int				(*is_in_guest)(void);
30 	int				(*is_user_mode)(void);
31 	unsigned long			(*get_guest_ip)(void);
32 };
33 
34 #ifdef CONFIG_HAVE_HW_BREAKPOINT
35 #include <asm/hw_breakpoint.h>
36 #endif
37 
38 #include <linux/list.h>
39 #include <linux/mutex.h>
40 #include <linux/rculist.h>
41 #include <linux/rcupdate.h>
42 #include <linux/spinlock.h>
43 #include <linux/hrtimer.h>
44 #include <linux/fs.h>
45 #include <linux/pid_namespace.h>
46 #include <linux/workqueue.h>
47 #include <linux/ftrace.h>
48 #include <linux/cpu.h>
49 #include <linux/irq_work.h>
50 #include <linux/static_key.h>
51 #include <linux/jump_label_ratelimit.h>
52 #include <linux/atomic.h>
53 #include <linux/sysfs.h>
54 #include <linux/perf_regs.h>
55 #include <asm/local.h>
56 
57 struct perf_callchain_entry {
58 	__u64				nr;
59 	__u64				ip[PERF_MAX_STACK_DEPTH];
60 };
61 
62 struct perf_raw_record {
63 	u32				size;
64 	void				*data;
65 };
66 
67 /*
68  * branch stack layout:
69  *  nr: number of taken branches stored in entries[]
70  *
71  * Note that nr can vary from sample to sample
72  * branches (to, from) are stored from most recent
73  * to least recent, i.e., entries[0] contains the most
74  * recent branch.
75  */
76 struct perf_branch_stack {
77 	__u64				nr;
78 	struct perf_branch_entry	entries[0];
79 };
80 
81 struct perf_regs_user {
82 	__u64		abi;
83 	struct pt_regs	*regs;
84 };
85 
86 struct task_struct;
87 
88 /*
89  * extra PMU register associated with an event
90  */
91 struct hw_perf_event_extra {
92 	u64		config;	/* register value */
93 	unsigned int	reg;	/* register address or index */
94 	int		alloc;	/* extra register already allocated */
95 	int		idx;	/* index in shared_regs->regs[] */
96 };
97 
98 struct event_constraint;
99 
100 /**
101  * struct hw_perf_event - performance event hardware details:
102  */
103 struct hw_perf_event {
104 #ifdef CONFIG_PERF_EVENTS
105 	union {
106 		struct { /* hardware */
107 			u64		config;
108 			u64		last_tag;
109 			unsigned long	config_base;
110 			unsigned long	event_base;
111 			int		event_base_rdpmc;
112 			int		idx;
113 			int		last_cpu;
114 			int		flags;
115 
116 			struct hw_perf_event_extra extra_reg;
117 			struct hw_perf_event_extra branch_reg;
118 
119 			struct event_constraint *constraint;
120 		};
121 		struct { /* software */
122 			struct hrtimer	hrtimer;
123 		};
124 		struct { /* tracepoint */
125 			struct task_struct	*tp_target;
126 			/* for tp_event->class */
127 			struct list_head	tp_list;
128 		};
129 #ifdef CONFIG_HAVE_HW_BREAKPOINT
130 		struct { /* breakpoint */
131 			/*
132 			 * Crufty hack to avoid the chicken and egg
133 			 * problem hw_breakpoint has with context
134 			 * creation and event initalization.
135 			 */
136 			struct task_struct		*bp_target;
137 			struct arch_hw_breakpoint	info;
138 			struct list_head		bp_list;
139 		};
140 #endif
141 	};
142 	int				state;
143 	local64_t			prev_count;
144 	u64				sample_period;
145 	u64				last_period;
146 	local64_t			period_left;
147 	u64                             interrupts_seq;
148 	u64				interrupts;
149 
150 	u64				freq_time_stamp;
151 	u64				freq_count_stamp;
152 #endif
153 };
154 
155 /*
156  * hw_perf_event::state flags
157  */
158 #define PERF_HES_STOPPED	0x01 /* the counter is stopped */
159 #define PERF_HES_UPTODATE	0x02 /* event->count up-to-date */
160 #define PERF_HES_ARCH		0x04
161 
162 struct perf_event;
163 
164 /*
165  * Common implementation detail of pmu::{start,commit,cancel}_txn
166  */
167 #define PERF_EVENT_TXN 0x1
168 
169 /**
170  * struct pmu - generic performance monitoring unit
171  */
172 struct pmu {
173 	struct list_head		entry;
174 
175 	struct device			*dev;
176 	const struct attribute_group	**attr_groups;
177 	const char			*name;
178 	int				type;
179 
180 	int * __percpu			pmu_disable_count;
181 	struct perf_cpu_context * __percpu pmu_cpu_context;
182 	int				task_ctx_nr;
183 	int				hrtimer_interval_ms;
184 
185 	/*
186 	 * Fully disable/enable this PMU, can be used to protect from the PMI
187 	 * as well as for lazy/batch writing of the MSRs.
188 	 */
189 	void (*pmu_enable)		(struct pmu *pmu); /* optional */
190 	void (*pmu_disable)		(struct pmu *pmu); /* optional */
191 
192 	/*
193 	 * Try and initialize the event for this PMU.
194 	 * Should return -ENOENT when the @event doesn't match this PMU.
195 	 */
196 	int (*event_init)		(struct perf_event *event);
197 
198 #define PERF_EF_START	0x01		/* start the counter when adding    */
199 #define PERF_EF_RELOAD	0x02		/* reload the counter when starting */
200 #define PERF_EF_UPDATE	0x04		/* update the counter when stopping */
201 
202 	/*
203 	 * Adds/Removes a counter to/from the PMU, can be done inside
204 	 * a transaction, see the ->*_txn() methods.
205 	 */
206 	int  (*add)			(struct perf_event *event, int flags);
207 	void (*del)			(struct perf_event *event, int flags);
208 
209 	/*
210 	 * Starts/Stops a counter present on the PMU. The PMI handler
211 	 * should stop the counter when perf_event_overflow() returns
212 	 * !0. ->start() will be used to continue.
213 	 */
214 	void (*start)			(struct perf_event *event, int flags);
215 	void (*stop)			(struct perf_event *event, int flags);
216 
217 	/*
218 	 * Updates the counter value of the event.
219 	 */
220 	void (*read)			(struct perf_event *event);
221 
222 	/*
223 	 * Group events scheduling is treated as a transaction, add
224 	 * group events as a whole and perform one schedulability test.
225 	 * If the test fails, roll back the whole group
226 	 *
227 	 * Start the transaction, after this ->add() doesn't need to
228 	 * do schedulability tests.
229 	 */
230 	void (*start_txn)		(struct pmu *pmu); /* optional */
231 	/*
232 	 * If ->start_txn() disabled the ->add() schedulability test
233 	 * then ->commit_txn() is required to perform one. On success
234 	 * the transaction is closed. On error the transaction is kept
235 	 * open until ->cancel_txn() is called.
236 	 */
237 	int  (*commit_txn)		(struct pmu *pmu); /* optional */
238 	/*
239 	 * Will cancel the transaction, assumes ->del() is called
240 	 * for each successful ->add() during the transaction.
241 	 */
242 	void (*cancel_txn)		(struct pmu *pmu); /* optional */
243 
244 	/*
245 	 * Will return the value for perf_event_mmap_page::index for this event,
246 	 * if no implementation is provided it will default to: event->hw.idx + 1.
247 	 */
248 	int (*event_idx)		(struct perf_event *event); /*optional */
249 
250 	/*
251 	 * flush branch stack on context-switches (needed in cpu-wide mode)
252 	 */
253 	void (*flush_branch_stack)	(void);
254 };
255 
256 /**
257  * enum perf_event_active_state - the states of a event
258  */
259 enum perf_event_active_state {
260 	PERF_EVENT_STATE_ERROR		= -2,
261 	PERF_EVENT_STATE_OFF		= -1,
262 	PERF_EVENT_STATE_INACTIVE	=  0,
263 	PERF_EVENT_STATE_ACTIVE		=  1,
264 };
265 
266 struct file;
267 struct perf_sample_data;
268 
269 typedef void (*perf_overflow_handler_t)(struct perf_event *,
270 					struct perf_sample_data *,
271 					struct pt_regs *regs);
272 
273 enum perf_group_flag {
274 	PERF_GROUP_SOFTWARE		= 0x1,
275 };
276 
277 #define SWEVENT_HLIST_BITS		8
278 #define SWEVENT_HLIST_SIZE		(1 << SWEVENT_HLIST_BITS)
279 
280 struct swevent_hlist {
281 	struct hlist_head		heads[SWEVENT_HLIST_SIZE];
282 	struct rcu_head			rcu_head;
283 };
284 
285 #define PERF_ATTACH_CONTEXT	0x01
286 #define PERF_ATTACH_GROUP	0x02
287 #define PERF_ATTACH_TASK	0x04
288 
289 struct perf_cgroup;
290 struct ring_buffer;
291 
292 /**
293  * struct perf_event - performance event kernel representation:
294  */
295 struct perf_event {
296 #ifdef CONFIG_PERF_EVENTS
297 	/*
298 	 * entry onto perf_event_context::event_list;
299 	 *   modifications require ctx->lock
300 	 *   RCU safe iterations.
301 	 */
302 	struct list_head		event_entry;
303 
304 	/*
305 	 * XXX: group_entry and sibling_list should be mutually exclusive;
306 	 * either you're a sibling on a group, or you're the group leader.
307 	 * Rework the code to always use the same list element.
308 	 *
309 	 * Locked for modification by both ctx->mutex and ctx->lock; holding
310 	 * either sufficies for read.
311 	 */
312 	struct list_head		group_entry;
313 	struct list_head		sibling_list;
314 
315 	/*
316 	 * We need storage to track the entries in perf_pmu_migrate_context; we
317 	 * cannot use the event_entry because of RCU and we want to keep the
318 	 * group in tact which avoids us using the other two entries.
319 	 */
320 	struct list_head		migrate_entry;
321 
322 	struct hlist_node		hlist_entry;
323 	int				nr_siblings;
324 	int				group_flags;
325 	struct perf_event		*group_leader;
326 	struct pmu			*pmu;
327 
328 	enum perf_event_active_state	state;
329 	unsigned int			attach_state;
330 	local64_t			count;
331 	atomic64_t			child_count;
332 
333 	/*
334 	 * These are the total time in nanoseconds that the event
335 	 * has been enabled (i.e. eligible to run, and the task has
336 	 * been scheduled in, if this is a per-task event)
337 	 * and running (scheduled onto the CPU), respectively.
338 	 *
339 	 * They are computed from tstamp_enabled, tstamp_running and
340 	 * tstamp_stopped when the event is in INACTIVE or ACTIVE state.
341 	 */
342 	u64				total_time_enabled;
343 	u64				total_time_running;
344 
345 	/*
346 	 * These are timestamps used for computing total_time_enabled
347 	 * and total_time_running when the event is in INACTIVE or
348 	 * ACTIVE state, measured in nanoseconds from an arbitrary point
349 	 * in time.
350 	 * tstamp_enabled: the notional time when the event was enabled
351 	 * tstamp_running: the notional time when the event was scheduled on
352 	 * tstamp_stopped: in INACTIVE state, the notional time when the
353 	 *	event was scheduled off.
354 	 */
355 	u64				tstamp_enabled;
356 	u64				tstamp_running;
357 	u64				tstamp_stopped;
358 
359 	/*
360 	 * timestamp shadows the actual context timing but it can
361 	 * be safely used in NMI interrupt context. It reflects the
362 	 * context time as it was when the event was last scheduled in.
363 	 *
364 	 * ctx_time already accounts for ctx->timestamp. Therefore to
365 	 * compute ctx_time for a sample, simply add perf_clock().
366 	 */
367 	u64				shadow_ctx_time;
368 
369 	struct perf_event_attr		attr;
370 	u16				header_size;
371 	u16				id_header_size;
372 	u16				read_size;
373 	struct hw_perf_event		hw;
374 
375 	struct perf_event_context	*ctx;
376 	atomic_long_t			refcount;
377 
378 	/*
379 	 * These accumulate total time (in nanoseconds) that children
380 	 * events have been enabled and running, respectively.
381 	 */
382 	atomic64_t			child_total_time_enabled;
383 	atomic64_t			child_total_time_running;
384 
385 	/*
386 	 * Protect attach/detach and child_list:
387 	 */
388 	struct mutex			child_mutex;
389 	struct list_head		child_list;
390 	struct perf_event		*parent;
391 
392 	int				oncpu;
393 	int				cpu;
394 
395 	struct list_head		owner_entry;
396 	struct task_struct		*owner;
397 
398 	/* mmap bits */
399 	struct mutex			mmap_mutex;
400 	atomic_t			mmap_count;
401 
402 	struct ring_buffer		*rb;
403 	struct list_head		rb_entry;
404 
405 	/* poll related */
406 	wait_queue_head_t		waitq;
407 	struct fasync_struct		*fasync;
408 
409 	/* delayed work for NMIs and such */
410 	int				pending_wakeup;
411 	int				pending_kill;
412 	int				pending_disable;
413 	struct irq_work			pending;
414 
415 	atomic_t			event_limit;
416 
417 	void (*destroy)(struct perf_event *);
418 	struct rcu_head			rcu_head;
419 
420 	struct pid_namespace		*ns;
421 	u64				id;
422 
423 	perf_overflow_handler_t		overflow_handler;
424 	void				*overflow_handler_context;
425 
426 #ifdef CONFIG_EVENT_TRACING
427 	struct ftrace_event_call	*tp_event;
428 	struct event_filter		*filter;
429 #ifdef CONFIG_FUNCTION_TRACER
430 	struct ftrace_ops               ftrace_ops;
431 #endif
432 #endif
433 
434 #ifdef CONFIG_CGROUP_PERF
435 	struct perf_cgroup		*cgrp; /* cgroup event is attach to */
436 	int				cgrp_defer_enabled;
437 #endif
438 
439 #endif /* CONFIG_PERF_EVENTS */
440 };
441 
442 enum perf_event_context_type {
443 	task_context,
444 	cpu_context,
445 };
446 
447 /**
448  * struct perf_event_context - event context structure
449  *
450  * Used as a container for task events and CPU events as well:
451  */
452 struct perf_event_context {
453 	struct pmu			*pmu;
454 	enum perf_event_context_type	type;
455 	/*
456 	 * Protect the states of the events in the list,
457 	 * nr_active, and the list:
458 	 */
459 	raw_spinlock_t			lock;
460 	/*
461 	 * Protect the list of events.  Locking either mutex or lock
462 	 * is sufficient to ensure the list doesn't change; to change
463 	 * the list you need to lock both the mutex and the spinlock.
464 	 */
465 	struct mutex			mutex;
466 
467 	struct list_head		pinned_groups;
468 	struct list_head		flexible_groups;
469 	struct list_head		event_list;
470 	int				nr_events;
471 	int				nr_active;
472 	int				is_active;
473 	int				nr_stat;
474 	int				nr_freq;
475 	int				rotate_disable;
476 	atomic_t			refcount;
477 	struct task_struct		*task;
478 
479 	/*
480 	 * Context clock, runs when context enabled.
481 	 */
482 	u64				time;
483 	u64				timestamp;
484 
485 	/*
486 	 * These fields let us detect when two contexts have both
487 	 * been cloned (inherited) from a common ancestor.
488 	 */
489 	struct perf_event_context	*parent_ctx;
490 	u64				parent_gen;
491 	u64				generation;
492 	int				pin_count;
493 	int				nr_cgroups;	 /* cgroup evts */
494 	int				nr_branch_stack; /* branch_stack evt */
495 	struct rcu_head			rcu_head;
496 };
497 
498 /*
499  * Number of contexts where an event can trigger:
500  *	task, softirq, hardirq, nmi.
501  */
502 #define PERF_NR_CONTEXTS	4
503 
504 /**
505  * struct perf_event_cpu_context - per cpu event context structure
506  */
507 struct perf_cpu_context {
508 	struct perf_event_context	ctx;
509 	struct perf_event_context	*task_ctx;
510 	int				active_oncpu;
511 	int				exclusive;
512 	struct hrtimer			hrtimer;
513 	ktime_t				hrtimer_interval;
514 	struct list_head		rotation_list;
515 	struct pmu			*unique_pmu;
516 	struct perf_cgroup		*cgrp;
517 };
518 
519 struct perf_output_handle {
520 	struct perf_event		*event;
521 	struct ring_buffer		*rb;
522 	unsigned long			wakeup;
523 	unsigned long			size;
524 	void				*addr;
525 	int				page;
526 };
527 
528 #ifdef CONFIG_PERF_EVENTS
529 
530 extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
531 extern void perf_pmu_unregister(struct pmu *pmu);
532 
533 extern int perf_num_counters(void);
534 extern const char *perf_pmu_name(void);
535 extern void __perf_event_task_sched_in(struct task_struct *prev,
536 				       struct task_struct *task);
537 extern void __perf_event_task_sched_out(struct task_struct *prev,
538 					struct task_struct *next);
539 extern int perf_event_init_task(struct task_struct *child);
540 extern void perf_event_exit_task(struct task_struct *child);
541 extern void perf_event_free_task(struct task_struct *task);
542 extern void perf_event_delayed_put(struct task_struct *task);
543 extern void perf_event_print_debug(void);
544 extern void perf_pmu_disable(struct pmu *pmu);
545 extern void perf_pmu_enable(struct pmu *pmu);
546 extern int perf_event_task_disable(void);
547 extern int perf_event_task_enable(void);
548 extern int perf_event_refresh(struct perf_event *event, int refresh);
549 extern void perf_event_update_userpage(struct perf_event *event);
550 extern int perf_event_release_kernel(struct perf_event *event);
551 extern struct perf_event *
552 perf_event_create_kernel_counter(struct perf_event_attr *attr,
553 				int cpu,
554 				struct task_struct *task,
555 				perf_overflow_handler_t callback,
556 				void *context);
557 extern void perf_pmu_migrate_context(struct pmu *pmu,
558 				int src_cpu, int dst_cpu);
559 extern u64 perf_event_read_value(struct perf_event *event,
560 				 u64 *enabled, u64 *running);
561 
562 
563 struct perf_sample_data {
564 	u64				type;
565 
566 	u64				ip;
567 	struct {
568 		u32	pid;
569 		u32	tid;
570 	}				tid_entry;
571 	u64				time;
572 	u64				addr;
573 	u64				id;
574 	u64				stream_id;
575 	struct {
576 		u32	cpu;
577 		u32	reserved;
578 	}				cpu_entry;
579 	u64				period;
580 	union  perf_mem_data_src	data_src;
581 	struct perf_callchain_entry	*callchain;
582 	struct perf_raw_record		*raw;
583 	struct perf_branch_stack	*br_stack;
584 	struct perf_regs_user		regs_user;
585 	u64				stack_user_size;
586 	u64				weight;
587 };
588 
perf_sample_data_init(struct perf_sample_data * data,u64 addr,u64 period)589 static inline void perf_sample_data_init(struct perf_sample_data *data,
590 					 u64 addr, u64 period)
591 {
592 	/* remaining struct members initialized in perf_prepare_sample() */
593 	data->addr = addr;
594 	data->raw  = NULL;
595 	data->br_stack = NULL;
596 	data->period = period;
597 	data->regs_user.abi = PERF_SAMPLE_REGS_ABI_NONE;
598 	data->regs_user.regs = NULL;
599 	data->stack_user_size = 0;
600 	data->weight = 0;
601 	data->data_src.val = 0;
602 }
603 
604 extern void perf_output_sample(struct perf_output_handle *handle,
605 			       struct perf_event_header *header,
606 			       struct perf_sample_data *data,
607 			       struct perf_event *event);
608 extern void perf_prepare_sample(struct perf_event_header *header,
609 				struct perf_sample_data *data,
610 				struct perf_event *event,
611 				struct pt_regs *regs);
612 
613 extern int perf_event_overflow(struct perf_event *event,
614 				 struct perf_sample_data *data,
615 				 struct pt_regs *regs);
616 
is_sampling_event(struct perf_event * event)617 static inline bool is_sampling_event(struct perf_event *event)
618 {
619 	return event->attr.sample_period != 0;
620 }
621 
622 /*
623  * Return 1 for a software event, 0 for a hardware event
624  */
is_software_event(struct perf_event * event)625 static inline int is_software_event(struct perf_event *event)
626 {
627 	return event->pmu->task_ctx_nr == perf_sw_context;
628 }
629 
630 extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
631 
632 extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
633 
634 #ifndef perf_arch_fetch_caller_regs
perf_arch_fetch_caller_regs(struct pt_regs * regs,unsigned long ip)635 static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
636 #endif
637 
638 /*
639  * Take a snapshot of the regs. Skip ip and frame pointer to
640  * the nth caller. We only need a few of the regs:
641  * - ip for PERF_SAMPLE_IP
642  * - cs for user_mode() tests
643  * - bp for callchains
644  * - eflags, for future purposes, just in case
645  */
perf_fetch_caller_regs(struct pt_regs * regs)646 static inline void perf_fetch_caller_regs(struct pt_regs *regs)
647 {
648 	memset(regs, 0, sizeof(*regs));
649 
650 	perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
651 }
652 
653 static __always_inline void
perf_sw_event(u32 event_id,u64 nr,struct pt_regs * regs,u64 addr)654 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
655 {
656 	struct pt_regs hot_regs;
657 
658 	if (static_key_false(&perf_swevent_enabled[event_id])) {
659 		if (!regs) {
660 			perf_fetch_caller_regs(&hot_regs);
661 			regs = &hot_regs;
662 		}
663 		__perf_sw_event(event_id, nr, regs, addr);
664 	}
665 }
666 
667 extern struct static_key_deferred perf_sched_events;
668 
perf_event_task_sched_in(struct task_struct * prev,struct task_struct * task)669 static inline void perf_event_task_sched_in(struct task_struct *prev,
670 					    struct task_struct *task)
671 {
672 	if (static_key_false(&perf_sched_events.key))
673 		__perf_event_task_sched_in(prev, task);
674 }
675 
perf_event_task_sched_out(struct task_struct * prev,struct task_struct * next)676 static inline void perf_event_task_sched_out(struct task_struct *prev,
677 					     struct task_struct *next)
678 {
679 	perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, NULL, 0);
680 
681 	if (static_key_false(&perf_sched_events.key))
682 		__perf_event_task_sched_out(prev, next);
683 }
684 
685 extern void perf_event_mmap(struct vm_area_struct *vma);
686 extern struct perf_guest_info_callbacks *perf_guest_cbs;
687 extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
688 extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
689 
690 extern void perf_event_comm(struct task_struct *tsk);
691 extern void perf_event_fork(struct task_struct *tsk);
692 
693 /* Callchains */
694 DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
695 
696 extern void perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs);
697 extern void perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs);
698 
perf_callchain_store(struct perf_callchain_entry * entry,u64 ip)699 static inline void perf_callchain_store(struct perf_callchain_entry *entry, u64 ip)
700 {
701 	if (entry->nr < PERF_MAX_STACK_DEPTH)
702 		entry->ip[entry->nr++] = ip;
703 }
704 
705 extern int sysctl_perf_event_paranoid;
706 extern int sysctl_perf_event_mlock;
707 extern int sysctl_perf_event_sample_rate;
708 extern int sysctl_perf_cpu_time_max_percent;
709 
710 extern void perf_sample_event_took(u64 sample_len_ns);
711 
712 extern int perf_proc_update_handler(struct ctl_table *table, int write,
713 		void __user *buffer, size_t *lenp,
714 		loff_t *ppos);
715 extern int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
716 		void __user *buffer, size_t *lenp,
717 		loff_t *ppos);
718 
719 
perf_paranoid_tracepoint_raw(void)720 static inline bool perf_paranoid_tracepoint_raw(void)
721 {
722 	return sysctl_perf_event_paranoid > -1;
723 }
724 
perf_paranoid_cpu(void)725 static inline bool perf_paranoid_cpu(void)
726 {
727 	return sysctl_perf_event_paranoid > 0;
728 }
729 
perf_paranoid_kernel(void)730 static inline bool perf_paranoid_kernel(void)
731 {
732 	return sysctl_perf_event_paranoid > 1;
733 }
734 
735 extern void perf_event_init(void);
736 extern void perf_tp_event(u64 addr, u64 count, void *record,
737 			  int entry_size, struct pt_regs *regs,
738 			  struct hlist_head *head, int rctx,
739 			  struct task_struct *task);
740 extern void perf_bp_event(struct perf_event *event, void *data);
741 
742 #ifndef perf_misc_flags
743 # define perf_misc_flags(regs) \
744 		(user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
745 # define perf_instruction_pointer(regs)	instruction_pointer(regs)
746 #endif
747 
has_branch_stack(struct perf_event * event)748 static inline bool has_branch_stack(struct perf_event *event)
749 {
750 	return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
751 }
752 
753 extern int perf_output_begin(struct perf_output_handle *handle,
754 			     struct perf_event *event, unsigned int size);
755 extern void perf_output_end(struct perf_output_handle *handle);
756 extern unsigned int perf_output_copy(struct perf_output_handle *handle,
757 			     const void *buf, unsigned int len);
758 extern unsigned int perf_output_skip(struct perf_output_handle *handle,
759 				     unsigned int len);
760 extern int perf_swevent_get_recursion_context(void);
761 extern void perf_swevent_put_recursion_context(int rctx);
762 extern u64 perf_swevent_set_period(struct perf_event *event);
763 extern void perf_event_enable(struct perf_event *event);
764 extern void perf_event_disable(struct perf_event *event);
765 extern int __perf_event_disable(void *info);
766 extern void perf_event_task_tick(void);
767 #else
768 static inline void
perf_event_task_sched_in(struct task_struct * prev,struct task_struct * task)769 perf_event_task_sched_in(struct task_struct *prev,
770 			 struct task_struct *task)			{ }
771 static inline void
perf_event_task_sched_out(struct task_struct * prev,struct task_struct * next)772 perf_event_task_sched_out(struct task_struct *prev,
773 			  struct task_struct *next)			{ }
perf_event_init_task(struct task_struct * child)774 static inline int perf_event_init_task(struct task_struct *child)	{ return 0; }
perf_event_exit_task(struct task_struct * child)775 static inline void perf_event_exit_task(struct task_struct *child)	{ }
perf_event_free_task(struct task_struct * task)776 static inline void perf_event_free_task(struct task_struct *task)	{ }
perf_event_delayed_put(struct task_struct * task)777 static inline void perf_event_delayed_put(struct task_struct *task)	{ }
perf_event_print_debug(void)778 static inline void perf_event_print_debug(void)				{ }
perf_event_task_disable(void)779 static inline int perf_event_task_disable(void)				{ return -EINVAL; }
perf_event_task_enable(void)780 static inline int perf_event_task_enable(void)				{ return -EINVAL; }
perf_event_refresh(struct perf_event * event,int refresh)781 static inline int perf_event_refresh(struct perf_event *event, int refresh)
782 {
783 	return -EINVAL;
784 }
785 
786 static inline void
perf_sw_event(u32 event_id,u64 nr,struct pt_regs * regs,u64 addr)787 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)	{ }
788 static inline void
perf_bp_event(struct perf_event * event,void * data)789 perf_bp_event(struct perf_event *event, void *data)			{ }
790 
perf_register_guest_info_callbacks(struct perf_guest_info_callbacks * callbacks)791 static inline int perf_register_guest_info_callbacks
792 (struct perf_guest_info_callbacks *callbacks)				{ return 0; }
perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks * callbacks)793 static inline int perf_unregister_guest_info_callbacks
794 (struct perf_guest_info_callbacks *callbacks)				{ return 0; }
795 
perf_event_mmap(struct vm_area_struct * vma)796 static inline void perf_event_mmap(struct vm_area_struct *vma)		{ }
perf_event_comm(struct task_struct * tsk)797 static inline void perf_event_comm(struct task_struct *tsk)		{ }
perf_event_fork(struct task_struct * tsk)798 static inline void perf_event_fork(struct task_struct *tsk)		{ }
perf_event_init(void)799 static inline void perf_event_init(void)				{ }
perf_swevent_get_recursion_context(void)800 static inline int  perf_swevent_get_recursion_context(void)		{ return -1; }
perf_swevent_put_recursion_context(int rctx)801 static inline void perf_swevent_put_recursion_context(int rctx)		{ }
perf_swevent_set_period(struct perf_event * event)802 static inline u64 perf_swevent_set_period(struct perf_event *event)	{ return 0; }
perf_event_enable(struct perf_event * event)803 static inline void perf_event_enable(struct perf_event *event)		{ }
perf_event_disable(struct perf_event * event)804 static inline void perf_event_disable(struct perf_event *event)		{ }
__perf_event_disable(void * info)805 static inline int __perf_event_disable(void *info)			{ return -1; }
perf_event_task_tick(void)806 static inline void perf_event_task_tick(void)				{ }
807 #endif
808 
809 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_NO_HZ_FULL)
810 extern bool perf_event_can_stop_tick(void);
811 #else
perf_event_can_stop_tick(void)812 static inline bool perf_event_can_stop_tick(void)			{ return true; }
813 #endif
814 
815 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
816 extern void perf_restore_debug_store(void);
817 #else
perf_restore_debug_store(void)818 static inline void perf_restore_debug_store(void)			{ }
819 #endif
820 
821 #define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
822 
823 /*
824  * This has to have a higher priority than migration_notifier in sched/core.c.
825  */
826 #define perf_cpu_notifier(fn)						\
827 do {									\
828 	static struct notifier_block fn##_nb =				\
829 		{ .notifier_call = fn, .priority = CPU_PRI_PERF };	\
830 	unsigned long cpu = smp_processor_id();				\
831 	unsigned long flags;						\
832 	fn(&fn##_nb, (unsigned long)CPU_UP_PREPARE,			\
833 		(void *)(unsigned long)cpu);				\
834 	local_irq_save(flags);						\
835 	fn(&fn##_nb, (unsigned long)CPU_STARTING,			\
836 		(void *)(unsigned long)cpu);				\
837 	local_irq_restore(flags);					\
838 	fn(&fn##_nb, (unsigned long)CPU_ONLINE,				\
839 		(void *)(unsigned long)cpu);				\
840 	register_cpu_notifier(&fn##_nb);				\
841 } while (0)
842 
843 
844 struct perf_pmu_events_attr {
845 	struct device_attribute attr;
846 	u64 id;
847 	const char *event_str;
848 };
849 
850 #define PMU_EVENT_ATTR(_name, _var, _id, _show)				\
851 static struct perf_pmu_events_attr _var = {				\
852 	.attr = __ATTR(_name, 0444, _show, NULL),			\
853 	.id   =  _id,							\
854 };
855 
856 #define PMU_FORMAT_ATTR(_name, _format)					\
857 static ssize_t								\
858 _name##_show(struct device *dev,					\
859 			       struct device_attribute *attr,		\
860 			       char *page)				\
861 {									\
862 	BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);			\
863 	return sprintf(page, _format "\n");				\
864 }									\
865 									\
866 static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
867 
868 #endif /* _LINUX_PERF_EVENT_H */
869