Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livep...
[cascardo/linux.git] / include / linux / perf_event.h
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 <linux/workqueue.h>
56 #include <asm/local.h>
57
58 struct perf_callchain_entry {
59         __u64                           nr;
60         __u64                           ip[PERF_MAX_STACK_DEPTH];
61 };
62
63 struct perf_raw_record {
64         u32                             size;
65         void                            *data;
66 };
67
68 /*
69  * branch stack layout:
70  *  nr: number of taken branches stored in entries[]
71  *
72  * Note that nr can vary from sample to sample
73  * branches (to, from) are stored from most recent
74  * to least recent, i.e., entries[0] contains the most
75  * recent branch.
76  */
77 struct perf_branch_stack {
78         __u64                           nr;
79         struct perf_branch_entry        entries[0];
80 };
81
82 struct task_struct;
83
84 /*
85  * extra PMU register associated with an event
86  */
87 struct hw_perf_event_extra {
88         u64             config; /* register value */
89         unsigned int    reg;    /* register address or index */
90         int             alloc;  /* extra register already allocated */
91         int             idx;    /* index in shared_regs->regs[] */
92 };
93
94 struct event_constraint;
95
96 /**
97  * struct hw_perf_event - performance event hardware details:
98  */
99 struct hw_perf_event {
100 #ifdef CONFIG_PERF_EVENTS
101         union {
102                 struct { /* hardware */
103                         u64             config;
104                         u64             last_tag;
105                         unsigned long   config_base;
106                         unsigned long   event_base;
107                         int             event_base_rdpmc;
108                         int             idx;
109                         int             last_cpu;
110                         int             flags;
111
112                         struct hw_perf_event_extra extra_reg;
113                         struct hw_perf_event_extra branch_reg;
114
115                         struct event_constraint *constraint;
116                 };
117                 struct { /* software */
118                         struct hrtimer  hrtimer;
119                 };
120                 struct { /* tracepoint */
121                         struct task_struct      *tp_target;
122                         /* for tp_event->class */
123                         struct list_head        tp_list;
124                 };
125 #ifdef CONFIG_HAVE_HW_BREAKPOINT
126                 struct { /* breakpoint */
127                         /*
128                          * Crufty hack to avoid the chicken and egg
129                          * problem hw_breakpoint has with context
130                          * creation and event initalization.
131                          */
132                         struct task_struct              *bp_target;
133                         struct arch_hw_breakpoint       info;
134                         struct list_head                bp_list;
135                 };
136 #endif
137         };
138         int                             state;
139         local64_t                       prev_count;
140         u64                             sample_period;
141         u64                             last_period;
142         local64_t                       period_left;
143         u64                             interrupts_seq;
144         u64                             interrupts;
145
146         u64                             freq_time_stamp;
147         u64                             freq_count_stamp;
148 #endif
149 };
150
151 /*
152  * hw_perf_event::state flags
153  */
154 #define PERF_HES_STOPPED        0x01 /* the counter is stopped */
155 #define PERF_HES_UPTODATE       0x02 /* event->count up-to-date */
156 #define PERF_HES_ARCH           0x04
157
158 struct perf_event;
159
160 /*
161  * Common implementation detail of pmu::{start,commit,cancel}_txn
162  */
163 #define PERF_EVENT_TXN 0x1
164
165 /**
166  * pmu::capabilities flags
167  */
168 #define PERF_PMU_CAP_NO_INTERRUPT               0x01
169
170 /**
171  * struct pmu - generic performance monitoring unit
172  */
173 struct pmu {
174         struct list_head                entry;
175
176         struct module                   *module;
177         struct device                   *dev;
178         const struct attribute_group    **attr_groups;
179         const char                      *name;
180         int                             type;
181
182         /*
183          * various common per-pmu feature flags
184          */
185         int                             capabilities;
186
187         int * __percpu                  pmu_disable_count;
188         struct perf_cpu_context * __percpu pmu_cpu_context;
189         int                             task_ctx_nr;
190         int                             hrtimer_interval_ms;
191
192         /*
193          * Fully disable/enable this PMU, can be used to protect from the PMI
194          * as well as for lazy/batch writing of the MSRs.
195          */
196         void (*pmu_enable)              (struct pmu *pmu); /* optional */
197         void (*pmu_disable)             (struct pmu *pmu); /* optional */
198
199         /*
200          * Try and initialize the event for this PMU.
201          * Should return -ENOENT when the @event doesn't match this PMU.
202          */
203         int (*event_init)               (struct perf_event *event);
204
205         /*
206          * Notification that the event was mapped or unmapped.  Called
207          * in the context of the mapping task.
208          */
209         void (*event_mapped)            (struct perf_event *event); /*optional*/
210         void (*event_unmapped)          (struct perf_event *event); /*optional*/
211
212 #define PERF_EF_START   0x01            /* start the counter when adding    */
213 #define PERF_EF_RELOAD  0x02            /* reload the counter when starting */
214 #define PERF_EF_UPDATE  0x04            /* update the counter when stopping */
215
216         /*
217          * Adds/Removes a counter to/from the PMU, can be done inside
218          * a transaction, see the ->*_txn() methods.
219          */
220         int  (*add)                     (struct perf_event *event, int flags);
221         void (*del)                     (struct perf_event *event, int flags);
222
223         /*
224          * Starts/Stops a counter present on the PMU. The PMI handler
225          * should stop the counter when perf_event_overflow() returns
226          * !0. ->start() will be used to continue.
227          */
228         void (*start)                   (struct perf_event *event, int flags);
229         void (*stop)                    (struct perf_event *event, int flags);
230
231         /*
232          * Updates the counter value of the event.
233          */
234         void (*read)                    (struct perf_event *event);
235
236         /*
237          * Group events scheduling is treated as a transaction, add
238          * group events as a whole and perform one schedulability test.
239          * If the test fails, roll back the whole group
240          *
241          * Start the transaction, after this ->add() doesn't need to
242          * do schedulability tests.
243          */
244         void (*start_txn)               (struct pmu *pmu); /* optional */
245         /*
246          * If ->start_txn() disabled the ->add() schedulability test
247          * then ->commit_txn() is required to perform one. On success
248          * the transaction is closed. On error the transaction is kept
249          * open until ->cancel_txn() is called.
250          */
251         int  (*commit_txn)              (struct pmu *pmu); /* optional */
252         /*
253          * Will cancel the transaction, assumes ->del() is called
254          * for each successful ->add() during the transaction.
255          */
256         void (*cancel_txn)              (struct pmu *pmu); /* optional */
257
258         /*
259          * Will return the value for perf_event_mmap_page::index for this event,
260          * if no implementation is provided it will default to: event->hw.idx + 1.
261          */
262         int (*event_idx)                (struct perf_event *event); /*optional */
263
264         /*
265          * flush branch stack on context-switches (needed in cpu-wide mode)
266          */
267         void (*flush_branch_stack)      (void);
268 };
269
270 /**
271  * enum perf_event_active_state - the states of a event
272  */
273 enum perf_event_active_state {
274         PERF_EVENT_STATE_EXIT           = -3,
275         PERF_EVENT_STATE_ERROR          = -2,
276         PERF_EVENT_STATE_OFF            = -1,
277         PERF_EVENT_STATE_INACTIVE       =  0,
278         PERF_EVENT_STATE_ACTIVE         =  1,
279 };
280
281 struct file;
282 struct perf_sample_data;
283
284 typedef void (*perf_overflow_handler_t)(struct perf_event *,
285                                         struct perf_sample_data *,
286                                         struct pt_regs *regs);
287
288 enum perf_group_flag {
289         PERF_GROUP_SOFTWARE             = 0x1,
290 };
291
292 #define SWEVENT_HLIST_BITS              8
293 #define SWEVENT_HLIST_SIZE              (1 << SWEVENT_HLIST_BITS)
294
295 struct swevent_hlist {
296         struct hlist_head               heads[SWEVENT_HLIST_SIZE];
297         struct rcu_head                 rcu_head;
298 };
299
300 #define PERF_ATTACH_CONTEXT     0x01
301 #define PERF_ATTACH_GROUP       0x02
302 #define PERF_ATTACH_TASK        0x04
303
304 struct perf_cgroup;
305 struct ring_buffer;
306
307 /**
308  * struct perf_event - performance event kernel representation:
309  */
310 struct perf_event {
311 #ifdef CONFIG_PERF_EVENTS
312         /*
313          * entry onto perf_event_context::event_list;
314          *   modifications require ctx->lock
315          *   RCU safe iterations.
316          */
317         struct list_head                event_entry;
318
319         /*
320          * XXX: group_entry and sibling_list should be mutually exclusive;
321          * either you're a sibling on a group, or you're the group leader.
322          * Rework the code to always use the same list element.
323          *
324          * Locked for modification by both ctx->mutex and ctx->lock; holding
325          * either sufficies for read.
326          */
327         struct list_head                group_entry;
328         struct list_head                sibling_list;
329
330         /*
331          * We need storage to track the entries in perf_pmu_migrate_context; we
332          * cannot use the event_entry because of RCU and we want to keep the
333          * group in tact which avoids us using the other two entries.
334          */
335         struct list_head                migrate_entry;
336
337         struct hlist_node               hlist_entry;
338         struct list_head                active_entry;
339         int                             nr_siblings;
340         int                             group_flags;
341         struct perf_event               *group_leader;
342         struct pmu                      *pmu;
343
344         enum perf_event_active_state    state;
345         unsigned int                    attach_state;
346         local64_t                       count;
347         atomic64_t                      child_count;
348
349         /*
350          * These are the total time in nanoseconds that the event
351          * has been enabled (i.e. eligible to run, and the task has
352          * been scheduled in, if this is a per-task event)
353          * and running (scheduled onto the CPU), respectively.
354          *
355          * They are computed from tstamp_enabled, tstamp_running and
356          * tstamp_stopped when the event is in INACTIVE or ACTIVE state.
357          */
358         u64                             total_time_enabled;
359         u64                             total_time_running;
360
361         /*
362          * These are timestamps used for computing total_time_enabled
363          * and total_time_running when the event is in INACTIVE or
364          * ACTIVE state, measured in nanoseconds from an arbitrary point
365          * in time.
366          * tstamp_enabled: the notional time when the event was enabled
367          * tstamp_running: the notional time when the event was scheduled on
368          * tstamp_stopped: in INACTIVE state, the notional time when the
369          *      event was scheduled off.
370          */
371         u64                             tstamp_enabled;
372         u64                             tstamp_running;
373         u64                             tstamp_stopped;
374
375         /*
376          * timestamp shadows the actual context timing but it can
377          * be safely used in NMI interrupt context. It reflects the
378          * context time as it was when the event was last scheduled in.
379          *
380          * ctx_time already accounts for ctx->timestamp. Therefore to
381          * compute ctx_time for a sample, simply add perf_clock().
382          */
383         u64                             shadow_ctx_time;
384
385         struct perf_event_attr          attr;
386         u16                             header_size;
387         u16                             id_header_size;
388         u16                             read_size;
389         struct hw_perf_event            hw;
390
391         struct perf_event_context       *ctx;
392         atomic_long_t                   refcount;
393
394         /*
395          * These accumulate total time (in nanoseconds) that children
396          * events have been enabled and running, respectively.
397          */
398         atomic64_t                      child_total_time_enabled;
399         atomic64_t                      child_total_time_running;
400
401         /*
402          * Protect attach/detach and child_list:
403          */
404         struct mutex                    child_mutex;
405         struct list_head                child_list;
406         struct perf_event               *parent;
407
408         int                             oncpu;
409         int                             cpu;
410
411         struct list_head                owner_entry;
412         struct task_struct              *owner;
413
414         /* mmap bits */
415         struct mutex                    mmap_mutex;
416         atomic_t                        mmap_count;
417
418         struct ring_buffer              *rb;
419         struct list_head                rb_entry;
420         unsigned long                   rcu_batches;
421         int                             rcu_pending;
422
423         /* poll related */
424         wait_queue_head_t               waitq;
425         struct fasync_struct            *fasync;
426
427         /* delayed work for NMIs and such */
428         int                             pending_wakeup;
429         int                             pending_kill;
430         int                             pending_disable;
431         struct irq_work                 pending;
432
433         atomic_t                        event_limit;
434
435         void (*destroy)(struct perf_event *);
436         struct rcu_head                 rcu_head;
437
438         struct pid_namespace            *ns;
439         u64                             id;
440
441         perf_overflow_handler_t         overflow_handler;
442         void                            *overflow_handler_context;
443
444 #ifdef CONFIG_EVENT_TRACING
445         struct ftrace_event_call        *tp_event;
446         struct event_filter             *filter;
447 #ifdef CONFIG_FUNCTION_TRACER
448         struct ftrace_ops               ftrace_ops;
449 #endif
450 #endif
451
452 #ifdef CONFIG_CGROUP_PERF
453         struct perf_cgroup              *cgrp; /* cgroup event is attach to */
454         int                             cgrp_defer_enabled;
455 #endif
456
457 #endif /* CONFIG_PERF_EVENTS */
458 };
459
460 /**
461  * struct perf_event_context - event context structure
462  *
463  * Used as a container for task events and CPU events as well:
464  */
465 struct perf_event_context {
466         struct pmu                      *pmu;
467         /*
468          * Protect the states of the events in the list,
469          * nr_active, and the list:
470          */
471         raw_spinlock_t                  lock;
472         /*
473          * Protect the list of events.  Locking either mutex or lock
474          * is sufficient to ensure the list doesn't change; to change
475          * the list you need to lock both the mutex and the spinlock.
476          */
477         struct mutex                    mutex;
478
479         struct list_head                active_ctx_list;
480         struct list_head                pinned_groups;
481         struct list_head                flexible_groups;
482         struct list_head                event_list;
483         int                             nr_events;
484         int                             nr_active;
485         int                             is_active;
486         int                             nr_stat;
487         int                             nr_freq;
488         int                             rotate_disable;
489         atomic_t                        refcount;
490         struct task_struct              *task;
491
492         /*
493          * Context clock, runs when context enabled.
494          */
495         u64                             time;
496         u64                             timestamp;
497
498         /*
499          * These fields let us detect when two contexts have both
500          * been cloned (inherited) from a common ancestor.
501          */
502         struct perf_event_context       *parent_ctx;
503         u64                             parent_gen;
504         u64                             generation;
505         int                             pin_count;
506         int                             nr_cgroups;      /* cgroup evts */
507         int                             nr_branch_stack; /* branch_stack evt */
508         struct rcu_head                 rcu_head;
509
510         struct delayed_work             orphans_remove;
511         bool                            orphans_remove_sched;
512 };
513
514 /*
515  * Number of contexts where an event can trigger:
516  *      task, softirq, hardirq, nmi.
517  */
518 #define PERF_NR_CONTEXTS        4
519
520 /**
521  * struct perf_event_cpu_context - per cpu event context structure
522  */
523 struct perf_cpu_context {
524         struct perf_event_context       ctx;
525         struct perf_event_context       *task_ctx;
526         int                             active_oncpu;
527         int                             exclusive;
528         struct hrtimer                  hrtimer;
529         ktime_t                         hrtimer_interval;
530         struct pmu                      *unique_pmu;
531         struct perf_cgroup              *cgrp;
532 };
533
534 struct perf_output_handle {
535         struct perf_event               *event;
536         struct ring_buffer              *rb;
537         unsigned long                   wakeup;
538         unsigned long                   size;
539         void                            *addr;
540         int                             page;
541 };
542
543 #ifdef CONFIG_PERF_EVENTS
544
545 extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
546 extern void perf_pmu_unregister(struct pmu *pmu);
547
548 extern int perf_num_counters(void);
549 extern const char *perf_pmu_name(void);
550 extern void __perf_event_task_sched_in(struct task_struct *prev,
551                                        struct task_struct *task);
552 extern void __perf_event_task_sched_out(struct task_struct *prev,
553                                         struct task_struct *next);
554 extern int perf_event_init_task(struct task_struct *child);
555 extern void perf_event_exit_task(struct task_struct *child);
556 extern void perf_event_free_task(struct task_struct *task);
557 extern void perf_event_delayed_put(struct task_struct *task);
558 extern void perf_event_print_debug(void);
559 extern void perf_pmu_disable(struct pmu *pmu);
560 extern void perf_pmu_enable(struct pmu *pmu);
561 extern int perf_event_task_disable(void);
562 extern int perf_event_task_enable(void);
563 extern int perf_event_refresh(struct perf_event *event, int refresh);
564 extern void perf_event_update_userpage(struct perf_event *event);
565 extern int perf_event_release_kernel(struct perf_event *event);
566 extern struct perf_event *
567 perf_event_create_kernel_counter(struct perf_event_attr *attr,
568                                 int cpu,
569                                 struct task_struct *task,
570                                 perf_overflow_handler_t callback,
571                                 void *context);
572 extern void perf_pmu_migrate_context(struct pmu *pmu,
573                                 int src_cpu, int dst_cpu);
574 extern u64 perf_event_read_value(struct perf_event *event,
575                                  u64 *enabled, u64 *running);
576
577
578 struct perf_sample_data {
579         /*
580          * Fields set by perf_sample_data_init(), group so as to
581          * minimize the cachelines touched.
582          */
583         u64                             addr;
584         struct perf_raw_record          *raw;
585         struct perf_branch_stack        *br_stack;
586         u64                             period;
587         u64                             weight;
588         u64                             txn;
589         union  perf_mem_data_src        data_src;
590
591         /*
592          * The other fields, optionally {set,used} by
593          * perf_{prepare,output}_sample().
594          */
595         u64                             type;
596         u64                             ip;
597         struct {
598                 u32     pid;
599                 u32     tid;
600         }                               tid_entry;
601         u64                             time;
602         u64                             id;
603         u64                             stream_id;
604         struct {
605                 u32     cpu;
606                 u32     reserved;
607         }                               cpu_entry;
608         struct perf_callchain_entry     *callchain;
609
610         /*
611          * regs_user may point to task_pt_regs or to regs_user_copy, depending
612          * on arch details.
613          */
614         struct perf_regs                regs_user;
615         struct pt_regs                  regs_user_copy;
616
617         struct perf_regs                regs_intr;
618         u64                             stack_user_size;
619 } ____cacheline_aligned;
620
621 /* default value for data source */
622 #define PERF_MEM_NA (PERF_MEM_S(OP, NA)   |\
623                     PERF_MEM_S(LVL, NA)   |\
624                     PERF_MEM_S(SNOOP, NA) |\
625                     PERF_MEM_S(LOCK, NA)  |\
626                     PERF_MEM_S(TLB, NA))
627
628 static inline void perf_sample_data_init(struct perf_sample_data *data,
629                                          u64 addr, u64 period)
630 {
631         /* remaining struct members initialized in perf_prepare_sample() */
632         data->addr = addr;
633         data->raw  = NULL;
634         data->br_stack = NULL;
635         data->period = period;
636         data->weight = 0;
637         data->data_src.val = PERF_MEM_NA;
638         data->txn = 0;
639 }
640
641 extern void perf_output_sample(struct perf_output_handle *handle,
642                                struct perf_event_header *header,
643                                struct perf_sample_data *data,
644                                struct perf_event *event);
645 extern void perf_prepare_sample(struct perf_event_header *header,
646                                 struct perf_sample_data *data,
647                                 struct perf_event *event,
648                                 struct pt_regs *regs);
649
650 extern int perf_event_overflow(struct perf_event *event,
651                                  struct perf_sample_data *data,
652                                  struct pt_regs *regs);
653
654 static inline bool is_sampling_event(struct perf_event *event)
655 {
656         return event->attr.sample_period != 0;
657 }
658
659 /*
660  * Return 1 for a software event, 0 for a hardware event
661  */
662 static inline int is_software_event(struct perf_event *event)
663 {
664         return event->pmu->task_ctx_nr == perf_sw_context;
665 }
666
667 extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
668
669 extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
670 extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
671
672 #ifndef perf_arch_fetch_caller_regs
673 static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
674 #endif
675
676 /*
677  * Take a snapshot of the regs. Skip ip and frame pointer to
678  * the nth caller. We only need a few of the regs:
679  * - ip for PERF_SAMPLE_IP
680  * - cs for user_mode() tests
681  * - bp for callchains
682  * - eflags, for future purposes, just in case
683  */
684 static inline void perf_fetch_caller_regs(struct pt_regs *regs)
685 {
686         memset(regs, 0, sizeof(*regs));
687
688         perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
689 }
690
691 static __always_inline void
692 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
693 {
694         if (static_key_false(&perf_swevent_enabled[event_id]))
695                 __perf_sw_event(event_id, nr, regs, addr);
696 }
697
698 DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);
699
700 /*
701  * 'Special' version for the scheduler, it hard assumes no recursion,
702  * which is guaranteed by us not actually scheduling inside other swevents
703  * because those disable preemption.
704  */
705 static __always_inline void
706 perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
707 {
708         if (static_key_false(&perf_swevent_enabled[event_id])) {
709                 struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
710
711                 perf_fetch_caller_regs(regs);
712                 ___perf_sw_event(event_id, nr, regs, addr);
713         }
714 }
715
716 extern struct static_key_deferred perf_sched_events;
717
718 static inline void perf_event_task_sched_in(struct task_struct *prev,
719                                             struct task_struct *task)
720 {
721         if (static_key_false(&perf_sched_events.key))
722                 __perf_event_task_sched_in(prev, task);
723 }
724
725 static inline void perf_event_task_sched_out(struct task_struct *prev,
726                                              struct task_struct *next)
727 {
728         perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);
729
730         if (static_key_false(&perf_sched_events.key))
731                 __perf_event_task_sched_out(prev, next);
732 }
733
734 extern void perf_event_mmap(struct vm_area_struct *vma);
735 extern struct perf_guest_info_callbacks *perf_guest_cbs;
736 extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
737 extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
738
739 extern void perf_event_exec(void);
740 extern void perf_event_comm(struct task_struct *tsk, bool exec);
741 extern void perf_event_fork(struct task_struct *tsk);
742
743 /* Callchains */
744 DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
745
746 extern void perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs);
747 extern void perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs);
748
749 static inline void perf_callchain_store(struct perf_callchain_entry *entry, u64 ip)
750 {
751         if (entry->nr < PERF_MAX_STACK_DEPTH)
752                 entry->ip[entry->nr++] = ip;
753 }
754
755 extern int sysctl_perf_event_paranoid;
756 extern int sysctl_perf_event_mlock;
757 extern int sysctl_perf_event_sample_rate;
758 extern int sysctl_perf_cpu_time_max_percent;
759
760 extern void perf_sample_event_took(u64 sample_len_ns);
761
762 extern int perf_proc_update_handler(struct ctl_table *table, int write,
763                 void __user *buffer, size_t *lenp,
764                 loff_t *ppos);
765 extern int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
766                 void __user *buffer, size_t *lenp,
767                 loff_t *ppos);
768
769
770 static inline bool perf_paranoid_tracepoint_raw(void)
771 {
772         return sysctl_perf_event_paranoid > -1;
773 }
774
775 static inline bool perf_paranoid_cpu(void)
776 {
777         return sysctl_perf_event_paranoid > 0;
778 }
779
780 static inline bool perf_paranoid_kernel(void)
781 {
782         return sysctl_perf_event_paranoid > 1;
783 }
784
785 extern void perf_event_init(void);
786 extern void perf_tp_event(u64 addr, u64 count, void *record,
787                           int entry_size, struct pt_regs *regs,
788                           struct hlist_head *head, int rctx,
789                           struct task_struct *task);
790 extern void perf_bp_event(struct perf_event *event, void *data);
791
792 #ifndef perf_misc_flags
793 # define perf_misc_flags(regs) \
794                 (user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
795 # define perf_instruction_pointer(regs) instruction_pointer(regs)
796 #endif
797
798 static inline bool has_branch_stack(struct perf_event *event)
799 {
800         return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
801 }
802
803 extern int perf_output_begin(struct perf_output_handle *handle,
804                              struct perf_event *event, unsigned int size);
805 extern void perf_output_end(struct perf_output_handle *handle);
806 extern unsigned int perf_output_copy(struct perf_output_handle *handle,
807                              const void *buf, unsigned int len);
808 extern unsigned int perf_output_skip(struct perf_output_handle *handle,
809                                      unsigned int len);
810 extern int perf_swevent_get_recursion_context(void);
811 extern void perf_swevent_put_recursion_context(int rctx);
812 extern u64 perf_swevent_set_period(struct perf_event *event);
813 extern void perf_event_enable(struct perf_event *event);
814 extern void perf_event_disable(struct perf_event *event);
815 extern int __perf_event_disable(void *info);
816 extern void perf_event_task_tick(void);
817 #else /* !CONFIG_PERF_EVENTS: */
818 static inline void
819 perf_event_task_sched_in(struct task_struct *prev,
820                          struct task_struct *task)                      { }
821 static inline void
822 perf_event_task_sched_out(struct task_struct *prev,
823                           struct task_struct *next)                     { }
824 static inline int perf_event_init_task(struct task_struct *child)       { return 0; }
825 static inline void perf_event_exit_task(struct task_struct *child)      { }
826 static inline void perf_event_free_task(struct task_struct *task)       { }
827 static inline void perf_event_delayed_put(struct task_struct *task)     { }
828 static inline void perf_event_print_debug(void)                         { }
829 static inline int perf_event_task_disable(void)                         { return -EINVAL; }
830 static inline int perf_event_task_enable(void)                          { return -EINVAL; }
831 static inline int perf_event_refresh(struct perf_event *event, int refresh)
832 {
833         return -EINVAL;
834 }
835
836 static inline void
837 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)     { }
838 static inline void
839 perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)                     { }
840 static inline void
841 perf_bp_event(struct perf_event *event, void *data)                     { }
842
843 static inline int perf_register_guest_info_callbacks
844 (struct perf_guest_info_callbacks *callbacks)                           { return 0; }
845 static inline int perf_unregister_guest_info_callbacks
846 (struct perf_guest_info_callbacks *callbacks)                           { return 0; }
847
848 static inline void perf_event_mmap(struct vm_area_struct *vma)          { }
849 static inline void perf_event_exec(void)                                { }
850 static inline void perf_event_comm(struct task_struct *tsk, bool exec)  { }
851 static inline void perf_event_fork(struct task_struct *tsk)             { }
852 static inline void perf_event_init(void)                                { }
853 static inline int  perf_swevent_get_recursion_context(void)             { return -1; }
854 static inline void perf_swevent_put_recursion_context(int rctx)         { }
855 static inline u64 perf_swevent_set_period(struct perf_event *event)     { return 0; }
856 static inline void perf_event_enable(struct perf_event *event)          { }
857 static inline void perf_event_disable(struct perf_event *event)         { }
858 static inline int __perf_event_disable(void *info)                      { return -1; }
859 static inline void perf_event_task_tick(void)                           { }
860 #endif
861
862 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_NO_HZ_FULL)
863 extern bool perf_event_can_stop_tick(void);
864 #else
865 static inline bool perf_event_can_stop_tick(void)                       { return true; }
866 #endif
867
868 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
869 extern void perf_restore_debug_store(void);
870 #else
871 static inline void perf_restore_debug_store(void)                       { }
872 #endif
873
874 #define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
875
876 /*
877  * This has to have a higher priority than migration_notifier in sched/core.c.
878  */
879 #define perf_cpu_notifier(fn)                                           \
880 do {                                                                    \
881         static struct notifier_block fn##_nb =                          \
882                 { .notifier_call = fn, .priority = CPU_PRI_PERF };      \
883         unsigned long cpu = smp_processor_id();                         \
884         unsigned long flags;                                            \
885                                                                         \
886         cpu_notifier_register_begin();                                  \
887         fn(&fn##_nb, (unsigned long)CPU_UP_PREPARE,                     \
888                 (void *)(unsigned long)cpu);                            \
889         local_irq_save(flags);                                          \
890         fn(&fn##_nb, (unsigned long)CPU_STARTING,                       \
891                 (void *)(unsigned long)cpu);                            \
892         local_irq_restore(flags);                                       \
893         fn(&fn##_nb, (unsigned long)CPU_ONLINE,                         \
894                 (void *)(unsigned long)cpu);                            \
895         __register_cpu_notifier(&fn##_nb);                              \
896         cpu_notifier_register_done();                                   \
897 } while (0)
898
899 /*
900  * Bare-bones version of perf_cpu_notifier(), which doesn't invoke the
901  * callback for already online CPUs.
902  */
903 #define __perf_cpu_notifier(fn)                                         \
904 do {                                                                    \
905         static struct notifier_block fn##_nb =                          \
906                 { .notifier_call = fn, .priority = CPU_PRI_PERF };      \
907                                                                         \
908         __register_cpu_notifier(&fn##_nb);                              \
909 } while (0)
910
911 struct perf_pmu_events_attr {
912         struct device_attribute attr;
913         u64 id;
914         const char *event_str;
915 };
916
917 ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
918                               char *page);
919
920 #define PMU_EVENT_ATTR(_name, _var, _id, _show)                         \
921 static struct perf_pmu_events_attr _var = {                             \
922         .attr = __ATTR(_name, 0444, _show, NULL),                       \
923         .id   =  _id,                                                   \
924 };
925
926 #define PMU_EVENT_ATTR_STRING(_name, _var, _str)                            \
927 static struct perf_pmu_events_attr _var = {                                 \
928         .attr           = __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
929         .id             = 0,                                                \
930         .event_str      = _str,                                             \
931 };
932
933 #define PMU_FORMAT_ATTR(_name, _format)                                 \
934 static ssize_t                                                          \
935 _name##_show(struct device *dev,                                        \
936                                struct device_attribute *attr,           \
937                                char *page)                              \
938 {                                                                       \
939         BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);                     \
940         return sprintf(page, _format "\n");                             \
941 }                                                                       \
942                                                                         \
943 static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
944
945 #endif /* _LINUX_PERF_EVENT_H */