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