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