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 #include <uapi/linux/bpf_perf_event.h>
  19
  20 /*
  21  * Kernel-internal data types and definitions:
  22  */
  23
  24 #ifdef CONFIG_PERF_EVENTS
  25 # include <asm/perf_event.h>
  26 # include <asm/local64.h>
  27 #endif
  28
  29 #define PERF_GUEST_ACTIVE       0x01
  30 #define PERF_GUEST_USER 0x02
  31
  32 struct perf_guest_info_callbacks {
  33         unsigned int                    (*state)(void);
  34         unsigned long                   (*get_ip)(void);
  35         unsigned int                    (*handle_intel_pt_intr)(void);
  36 };
  37
  38 #ifdef CONFIG_HAVE_HW_BREAKPOINT
  39 #include <linux/rhashtable-types.h>
  40 #include <asm/hw_breakpoint.h>
  41 #endif
  42
  43 #include <linux/list.h>
  44 #include <linux/mutex.h>
  45 #include <linux/rculist.h>
  46 #include <linux/rcupdate.h>
  47 #include <linux/spinlock.h>
  48 #include <linux/hrtimer.h>
  49 #include <linux/fs.h>
  50 #include <linux/pid_namespace.h>
  51 #include <linux/workqueue.h>
  52 #include <linux/ftrace.h>
  53 #include <linux/cpu.h>
  54 #include <linux/irq_work.h>
  55 #include <linux/static_key.h>
  56 #include <linux/jump_label_ratelimit.h>
  57 #include <linux/atomic.h>
  58 #include <linux/sysfs.h>
  59 #include <linux/perf_regs.h>
  60 #include <linux/cgroup.h>
  61 #include <linux/refcount.h>
  62 #include <linux/security.h>
  63 #include <linux/static_call.h>
  64 #include <linux/lockdep.h>
  65 #include <asm/local.h>
  66
  67 struct perf_callchain_entry {
  68         __u64                           nr;
  69         __u64                           ip[]; /* /proc/sys/kernel/perf_event_max_stack */
  70 };
  71
  72 struct perf_callchain_entry_ctx {
  73         struct perf_callchain_entry *entry;
  74         u32                         max_stack;
  75         u32                         nr;
  76         short                       contexts;
  77         bool                        contexts_maxed;
  78 };
  79
  80 typedef unsigned long (*perf_copy_f)(void *dst, const void *src,
  81                                      unsigned long off, unsigned long len);
  82
  83 struct perf_raw_frag {
  84         union {
  85                 struct perf_raw_frag    *next;
  86                 unsigned long           pad;
  87         };
  88         perf_copy_f                     copy;
  89         void                            *data;
  90         u32                             size;
  91 } __packed;
  92
  93 struct perf_raw_record {
  94         struct perf_raw_frag            frag;
  95         u32                             size;
  96 };
  97
  98 static __always_inline bool perf_raw_frag_last(const struct perf_raw_frag *frag)
  99 {
 100         return frag->pad < sizeof(u64);
 101 }
 102
 103 /*
 104  * branch stack layout:
 105  *  nr: number of taken branches stored in entries[]
 106  *  hw_idx: The low level index of raw branch records
 107  *          for the most recent branch.
 108  *          -1ULL means invalid/unknown.
 109  *
 110  * Note that nr can vary from sample to sample
 111  * branches (to, from) are stored from most recent
 112  * to least recent, i.e., entries[0] contains the most
 113  * recent branch.
 114  * The entries[] is an abstraction of raw branch records,
 115  * which may not be stored in age order in HW, e.g. Intel LBR.
 116  * The hw_idx is to expose the low level index of raw
 117  * branch record for the most recent branch aka entries[0].
 118  * The hw_idx index is between -1 (unknown) and max depth,
 119  * which can be retrieved in /sys/devices/cpu/caps/branches.
 120  * For the architectures whose raw branch records are
 121  * already stored in age order, the hw_idx should be 0.
 122  */
 123 struct perf_branch_stack {
 124         __u64                           nr;
 125         __u64                           hw_idx;
 126         struct perf_branch_entry        entries[];
 127 };
 128
 129 struct task_struct;
 130
 131 /*
 132  * extra PMU register associated with an event
 133  */
 134 struct hw_perf_event_extra {
 135         u64             config; /* register value */
 136         unsigned int    reg;    /* register address or index */
 137         int             alloc;  /* extra register already allocated */
 138         int             idx;    /* index in shared_regs->regs[] */
 139 };
 140
 141 /**
 142  * hw_perf_event::flag values
 143  *
 144  * PERF_EVENT_FLAG_ARCH bits are reserved for architecture-specific
 145  * usage.
 146  */
 147 #define PERF_EVENT_FLAG_ARCH                    0x000fffff
 148 #define PERF_EVENT_FLAG_USER_READ_CNT           0x80000000
 149
 150 static_assert((PERF_EVENT_FLAG_USER_READ_CNT & PERF_EVENT_FLAG_ARCH) == 0);
 151
 152 /**
 153  * struct hw_perf_event - performance event hardware details:
 154  */
 155 struct hw_perf_event {
 156 #ifdef CONFIG_PERF_EVENTS
 157         union {
 158                 struct { /* hardware */
 159                         u64             config;
 160                         u64             last_tag;
 161                         unsigned long   config_base;
 162                         unsigned long   event_base;
 163                         int             event_base_rdpmc;
 164                         int             idx;
 165                         int             last_cpu;
 166                         int             flags;
 167
 168                         struct hw_perf_event_extra extra_reg;
 169                         struct hw_perf_event_extra branch_reg;
 170                 };
 171                 struct { /* software */
 172                         struct hrtimer  hrtimer;
 173                 };
 174                 struct { /* tracepoint */
 175                         /* for tp_event->class */
 176                         struct list_head        tp_list;
 177                 };
 178                 struct { /* amd_power */
 179                         u64     pwr_acc;
 180                         u64     ptsc;
 181                 };
 182 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 183                 struct { /* breakpoint */
 184                         /*
 185                          * Crufty hack to avoid the chicken and egg
 186                          * problem hw_breakpoint has with context
 187                          * creation and event initalization.
 188                          */
 189                         struct arch_hw_breakpoint       info;
 190                         struct rhlist_head              bp_list;
 191                 };
 192 #endif
 193                 struct { /* amd_iommu */
 194                         u8      iommu_bank;
 195                         u8      iommu_cntr;
 196                         u16     padding;
 197                         u64     conf;
 198                         u64     conf1;
 199                 };
 200         };
 201         /*
 202          * If the event is a per task event, this will point to the task in
 203          * question. See the comment in perf_event_alloc().
 204          */
 205         struct task_struct              *target;
 206
 207         /*
 208          * PMU would store hardware filter configuration
 209          * here.
 210          */
 211         void                            *addr_filters;
 212
 213         /* Last sync'ed generation of filters */
 214         unsigned long                   addr_filters_gen;
 215
 216 /*
 217  * hw_perf_event::state flags; used to track the PERF_EF_* state.
 218  */
 219 #define PERF_HES_STOPPED        0x01 /* the counter is stopped */
 220 #define PERF_HES_UPTODATE       0x02 /* event->count up-to-date */
 221 #define PERF_HES_ARCH           0x04
 222
 223         int                             state;
 224
 225         /*
 226          * The last observed hardware counter value, updated with a
 227          * local64_cmpxchg() such that pmu::read() can be called nested.
 228          */
 229         local64_t                       prev_count;
 230
 231         /*
 232          * The period to start the next sample with.
 233          */
 234         u64                             sample_period;
 235
 236         union {
 237                 struct { /* Sampling */
 238                         /*
 239                          * The period we started this sample with.
 240                          */
 241                         u64                             last_period;
 242
 243                         /*
 244                          * However much is left of the current period;
 245                          * note that this is a full 64bit value and
 246                          * allows for generation of periods longer
 247                          * than hardware might allow.
 248                          */
 249                         local64_t                       period_left;
 250                 };
 251                 struct { /* Topdown events counting for context switch */
 252                         u64                             saved_metric;
 253                         u64                             saved_slots;
 254                 };
 255         };
 256
 257         /*
 258          * State for throttling the event, see __perf_event_overflow() and
 259          * perf_adjust_freq_unthr_context().
 260          */
 261         u64                             interrupts_seq;
 262         u64                             interrupts;
 263
 264         /*
 265          * State for freq target events, see __perf_event_overflow() and
 266          * perf_adjust_freq_unthr_context().
 267          */
 268         u64                             freq_time_stamp;
 269         u64                             freq_count_stamp;
 270 #endif
 271 };
 272
 273 struct perf_event;
 274 struct perf_event_pmu_context;
 275
 276 /*
 277  * Common implementation detail of pmu::{start,commit,cancel}_txn
 278  */
 279 #define PERF_PMU_TXN_ADD  0x1           /* txn to add/schedule event on PMU */
 280 #define PERF_PMU_TXN_READ 0x2           /* txn to read event group from PMU */
 281
 282 /**
 283  * pmu::capabilities flags
 284  */
 285 #define PERF_PMU_CAP_NO_INTERRUPT               0x0001
 286 #define PERF_PMU_CAP_NO_NMI                     0x0002
 287 #define PERF_PMU_CAP_AUX_NO_SG                  0x0004
 288 #define PERF_PMU_CAP_EXTENDED_REGS              0x0008
 289 #define PERF_PMU_CAP_EXCLUSIVE                  0x0010
 290 #define PERF_PMU_CAP_ITRACE                     0x0020
 291 #define PERF_PMU_CAP_NO_EXCLUDE                 0x0040
 292 #define PERF_PMU_CAP_AUX_OUTPUT                 0x0080
 293 #define PERF_PMU_CAP_EXTENDED_HW_TYPE           0x0100
 294
 295 struct perf_output_handle;
 296
 297 #define PMU_NULL_DEV    ((void *)(~0UL))
 298
 299 /**
 300  * struct pmu - generic performance monitoring unit
 301  */
 302 struct pmu {
 303         struct list_head                entry;
 304
 305         struct module                   *module;
 306         struct device                   *dev;
 307         struct device                   *parent;
 308         const struct attribute_group    **attr_groups;
 309         const struct attribute_group    **attr_update;
 310         const char                      *name;
 311         int                             type;
 312
 313         /*
 314          * various common per-pmu feature flags
 315          */
 316         int                             capabilities;
 317
 318         int __percpu                    *pmu_disable_count;
 319         struct perf_cpu_pmu_context __percpu *cpu_pmu_context;
 320         atomic_t                        exclusive_cnt; /* < 0: cpu; > 0: tsk */
 321         int                             task_ctx_nr;
 322         int                             hrtimer_interval_ms;
 323
 324         /* number of address filters this PMU can do */
 325         unsigned int                    nr_addr_filters;
 326
 327         /*
 328          * Fully disable/enable this PMU, can be used to protect from the PMI
 329          * as well as for lazy/batch writing of the MSRs.
 330          */
 331         void (*pmu_enable)              (struct pmu *pmu); /* optional */
 332         void (*pmu_disable)             (struct pmu *pmu); /* optional */
 333
 334         /*
 335          * Try and initialize the event for this PMU.
 336          *
 337          * Returns:
 338          *  -ENOENT     -- @event is not for this PMU
 339          *
 340          *  -ENODEV     -- @event is for this PMU but PMU not present
 341          *  -EBUSY      -- @event is for this PMU but PMU temporarily unavailable
 342          *  -EINVAL     -- @event is for this PMU but @event is not valid
 343          *  -EOPNOTSUPP -- @event is for this PMU, @event is valid, but not supported
 344          *  -EACCES     -- @event is for this PMU, @event is valid, but no privileges
 345          *
 346          *  0           -- @event is for this PMU and valid
 347          *
 348          * Other error return values are allowed.
 349          */
 350         int (*event_init)               (struct perf_event *event);
 351
 352         /*
 353          * Notification that the event was mapped or unmapped.  Called
 354          * in the context of the mapping task.
 355          */
 356         void (*event_mapped)            (struct perf_event *event, struct mm_struct *mm); /* optional */
 357         void (*event_unmapped)          (struct perf_event *event, struct mm_struct *mm); /* optional */
 358
 359         /*
 360          * Flags for ->add()/->del()/ ->start()/->stop(). There are
 361          * matching hw_perf_event::state flags.
 362          */
 363 #define PERF_EF_START   0x01            /* start the counter when adding    */
 364 #define PERF_EF_RELOAD  0x02            /* reload the counter when starting */
 365 #define PERF_EF_UPDATE  0x04            /* update the counter when stopping */
 366
 367         /*
 368          * Adds/Removes a counter to/from the PMU, can be done inside a
 369          * transaction, see the ->*_txn() methods.
 370          *
 371          * The add/del callbacks will reserve all hardware resources required
 372          * to service the event, this includes any counter constraint
 373          * scheduling etc.
 374          *
 375          * Called with IRQs disabled and the PMU disabled on the CPU the event
 376          * is on.
 377          *
 378          * ->add() called without PERF_EF_START should result in the same state
 379          *  as ->add() followed by ->stop().
 380          *
 381          * ->del() must always PERF_EF_UPDATE stop an event. If it calls
 382          *  ->stop() that must deal with already being stopped without
 383          *  PERF_EF_UPDATE.
 384          */
 385         int  (*add)                     (struct perf_event *event, int flags);
 386         void (*del)                     (struct perf_event *event, int flags);
 387
 388         /*
 389          * Starts/Stops a counter present on the PMU.
 390          *
 391          * The PMI handler should stop the counter when perf_event_overflow()
 392          * returns !0. ->start() will be used to continue.
 393          *
 394          * Also used to change the sample period.
 395          *
 396          * Called with IRQs disabled and the PMU disabled on the CPU the event
 397          * is on -- will be called from NMI context with the PMU generates
 398          * NMIs.
 399          *
 400          * ->stop() with PERF_EF_UPDATE will read the counter and update
 401          *  period/count values like ->read() would.
 402          *
 403          * ->start() with PERF_EF_RELOAD will reprogram the counter
 404          *  value, must be preceded by a ->stop() with PERF_EF_UPDATE.
 405          */
 406         void (*start)                   (struct perf_event *event, int flags);
 407         void (*stop)                    (struct perf_event *event, int flags);
 408
 409         /*
 410          * Updates the counter value of the event.
 411          *
 412          * For sampling capable PMUs this will also update the software period
 413          * hw_perf_event::period_left field.
 414          */
 415         void (*read)                    (struct perf_event *event);
 416
 417         /*
 418          * Group events scheduling is treated as a transaction, add
 419          * group events as a whole and perform one schedulability test.
 420          * If the test fails, roll back the whole group
 421          *
 422          * Start the transaction, after this ->add() doesn't need to
 423          * do schedulability tests.
 424          *
 425          * Optional.
 426          */
 427         void (*start_txn)               (struct pmu *pmu, unsigned int txn_flags);
 428         /*
 429          * If ->start_txn() disabled the ->add() schedulability test
 430          * then ->commit_txn() is required to perform one. On success
 431          * the transaction is closed. On error the transaction is kept
 432          * open until ->cancel_txn() is called.
 433          *
 434          * Optional.
 435          */
 436         int  (*commit_txn)              (struct pmu *pmu);
 437         /*
 438          * Will cancel the transaction, assumes ->del() is called
 439          * for each successful ->add() during the transaction.
 440          *
 441          * Optional.
 442          */
 443         void (*cancel_txn)              (struct pmu *pmu);
 444
 445         /*
 446          * Will return the value for perf_event_mmap_page::index for this event,
 447          * if no implementation is provided it will default to 0 (see
 448          * perf_event_idx_default).
 449          */
 450         int (*event_idx)                (struct perf_event *event); /*optional */
 451
 452         /*
 453          * context-switches callback
 454          */
 455         void (*sched_task)              (struct perf_event_pmu_context *pmu_ctx,
 456                                         bool sched_in);
 457
 458         /*
 459          * Kmem cache of PMU specific data
 460          */
 461         struct kmem_cache               *task_ctx_cache;
 462
 463         /*
 464          * PMU specific parts of task perf event context (i.e. ctx->task_ctx_data)
 465          * can be synchronized using this function. See Intel LBR callstack support
 466          * implementation and Perf core context switch handling callbacks for usage
 467          * examples.
 468          */
 469         void (*swap_task_ctx)           (struct perf_event_pmu_context *prev_epc,
 470                                          struct perf_event_pmu_context *next_epc);
 471                                         /* optional */
 472
 473         /*
 474          * Set up pmu-private data structures for an AUX area
 475          */
 476         void *(*setup_aux)              (struct perf_event *event, void **pages,
 477                                          int nr_pages, bool overwrite);
 478                                         /* optional */
 479
 480         /*
 481          * Free pmu-private AUX data structures
 482          */
 483         void (*free_aux)                (void *aux); /* optional */
 484
 485         /*
 486          * Take a snapshot of the AUX buffer without touching the event
 487          * state, so that preempting ->start()/->stop() callbacks does
 488          * not interfere with their logic. Called in PMI context.
 489          *
 490          * Returns the size of AUX data copied to the output handle.
 491          *
 492          * Optional.
 493          */
 494         long (*snapshot_aux)            (struct perf_event *event,
 495                                          struct perf_output_handle *handle,
 496                                          unsigned long size);
 497
 498         /*
 499          * Validate address range filters: make sure the HW supports the
 500          * requested configuration and number of filters; return 0 if the
 501          * supplied filters are valid, -errno otherwise.
 502          *
 503          * Runs in the context of the ioctl()ing process and is not serialized
 504          * with the rest of the PMU callbacks.
 505          */
 506         int (*addr_filters_validate)    (struct list_head *filters);
 507                                         /* optional */
 508
 509         /*
 510          * Synchronize address range filter configuration:
 511          * translate hw-agnostic filters into hardware configuration in
 512          * event::hw::addr_filters.
 513          *
 514          * Runs as a part of filter sync sequence that is done in ->start()
 515          * callback by calling perf_event_addr_filters_sync().
 516          *
 517          * May (and should) traverse event::addr_filters::list, for which its
 518          * caller provides necessary serialization.
 519          */
 520         void (*addr_filters_sync)       (struct perf_event *event);
 521                                         /* optional */
 522
 523         /*
 524          * Check if event can be used for aux_output purposes for
 525          * events of this PMU.
 526          *
 527          * Runs from perf_event_open(). Should return 0 for "no match"
 528          * or non-zero for "match".
 529          */
 530         int (*aux_output_match)         (struct perf_event *event);
 531                                         /* optional */
 532
 533         /*
 534          * Skip programming this PMU on the given CPU. Typically needed for
 535          * big.LITTLE things.
 536          */
 537         bool (*filter)                  (struct pmu *pmu, int cpu); /* optional */
 538
 539         /*
 540          * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
 541          */
 542         int (*check_period)             (struct perf_event *event, u64 value); /* optional */
 543 };
 544
 545 enum perf_addr_filter_action_t {
 546         PERF_ADDR_FILTER_ACTION_STOP = 0,
 547         PERF_ADDR_FILTER_ACTION_START,
 548         PERF_ADDR_FILTER_ACTION_FILTER,
 549 };
 550
 551 /**
 552  * struct perf_addr_filter - address range filter definition
 553  * @entry:      event's filter list linkage
 554  * @path:       object file's path for file-based filters
 555  * @offset:     filter range offset
 556  * @size:       filter range size (size==0 means single address trigger)
 557  * @action:     filter/start/stop
 558  *
 559  * This is a hardware-agnostic filter configuration as specified by the user.
 560  */
 561 struct perf_addr_filter {
 562         struct list_head        entry;
 563         struct path             path;
 564         unsigned long           offset;
 565         unsigned long           size;
 566         enum perf_addr_filter_action_t  action;
 567 };
 568
 569 /**
 570  * struct perf_addr_filters_head - container for address range filters
 571  * @list:       list of filters for this event
 572  * @lock:       spinlock that serializes accesses to the @list and event's
 573  *              (and its children's) filter generations.
 574  * @nr_file_filters:    number of file-based filters
 575  *
 576  * A child event will use parent's @list (and therefore @lock), so they are
 577  * bundled together; see perf_event_addr_filters().
 578  */
 579 struct perf_addr_filters_head {
 580         struct list_head        list;
 581         raw_spinlock_t          lock;
 582         unsigned int            nr_file_filters;
 583 };
 584
 585 struct perf_addr_filter_range {
 586         unsigned long           start;
 587         unsigned long           size;
 588 };
 589
 590 /**
 591  * enum perf_event_state - the states of an event:
 592  */
 593 enum perf_event_state {
 594         PERF_EVENT_STATE_DEAD           = -4,
 595         PERF_EVENT_STATE_EXIT           = -3,
 596         PERF_EVENT_STATE_ERROR          = -2,
 597         PERF_EVENT_STATE_OFF            = -1,
 598         PERF_EVENT_STATE_INACTIVE       =  0,
 599         PERF_EVENT_STATE_ACTIVE         =  1,
 600 };
 601
 602 struct file;
 603 struct perf_sample_data;
 604
 605 typedef void (*perf_overflow_handler_t)(struct perf_event *,
 606                                         struct perf_sample_data *,
 607                                         struct pt_regs *regs);
 608
 609 /*
 610  * Event capabilities. For event_caps and groups caps.
 611  *
 612  * PERF_EV_CAP_SOFTWARE: Is a software event.
 613  * PERF_EV_CAP_READ_ACTIVE_PKG: A CPU event (or cgroup event) that can be read
 614  * from any CPU in the package where it is active.
 615  * PERF_EV_CAP_SIBLING: An event with this flag must be a group sibling and
 616  * cannot be a group leader. If an event with this flag is detached from the
 617  * group it is scheduled out and moved into an unrecoverable ERROR state.
 618  */
 619 #define PERF_EV_CAP_SOFTWARE            BIT(0)
 620 #define PERF_EV_CAP_READ_ACTIVE_PKG     BIT(1)
 621 #define PERF_EV_CAP_SIBLING             BIT(2)
 622
 623 #define SWEVENT_HLIST_BITS              8
 624 #define SWEVENT_HLIST_SIZE              (1 << SWEVENT_HLIST_BITS)
 625
 626 struct swevent_hlist {
 627         struct hlist_head               heads[SWEVENT_HLIST_SIZE];
 628         struct rcu_head                 rcu_head;
 629 };
 630
 631 #define PERF_ATTACH_CONTEXT     0x01
 632 #define PERF_ATTACH_GROUP       0x02
 633 #define PERF_ATTACH_TASK        0x04
 634 #define PERF_ATTACH_TASK_DATA   0x08
 635 #define PERF_ATTACH_ITRACE      0x10
 636 #define PERF_ATTACH_SCHED_CB    0x20
 637 #define PERF_ATTACH_CHILD       0x40
 638
 639 struct bpf_prog;
 640 struct perf_cgroup;
 641 struct perf_buffer;
 642
 643 struct pmu_event_list {
 644         raw_spinlock_t          lock;
 645         struct list_head        list;
 646 };
 647
 648 /*
 649  * event->sibling_list is modified whole holding both ctx->lock and ctx->mutex
 650  * as such iteration must hold either lock. However, since ctx->lock is an IRQ
 651  * safe lock, and is only held by the CPU doing the modification, having IRQs
 652  * disabled is sufficient since it will hold-off the IPIs.
 653  */
 654 #ifdef CONFIG_PROVE_LOCKING
 655 #define lockdep_assert_event_ctx(event)                         \
 656         WARN_ON_ONCE(__lockdep_enabled &&                       \
 657                      (this_cpu_read(hardirqs_enabled) &&        \
 658                       lockdep_is_held(&(event)->ctx->mutex) != LOCK_STATE_HELD))
 659 #else
 660 #define lockdep_assert_event_ctx(event)
 661 #endif
 662
 663 #define for_each_sibling_event(sibling, event)                  \
 664         lockdep_assert_event_ctx(event);                        \
 665         if ((event)->group_leader == (event))                   \
 666                 list_for_each_entry((sibling), &(event)->sibling_list, sibling_list)
 667
 668 /**
 669  * struct perf_event - performance event kernel representation:
 670  */
 671 struct perf_event {
 672 #ifdef CONFIG_PERF_EVENTS
 673         /*
 674          * entry onto perf_event_context::event_list;
 675          *   modifications require ctx->lock
 676          *   RCU safe iterations.
 677          */
 678         struct list_head                event_entry;
 679
 680         /*
 681          * Locked for modification by both ctx->mutex and ctx->lock; holding
 682          * either sufficies for read.
 683          */
 684         struct list_head                sibling_list;
 685         struct list_head                active_list;
 686         /*
 687          * Node on the pinned or flexible tree located at the event context;
 688          */
 689         struct rb_node                  group_node;
 690         u64                             group_index;
 691         /*
 692          * We need storage to track the entries in perf_pmu_migrate_context; we
 693          * cannot use the event_entry because of RCU and we want to keep the
 694          * group in tact which avoids us using the other two entries.
 695          */
 696         struct list_head                migrate_entry;
 697
 698         struct hlist_node               hlist_entry;
 699         struct list_head                active_entry;
 700         int                             nr_siblings;
 701
 702         /* Not serialized. Only written during event initialization. */
 703         int                             event_caps;
 704         /* The cumulative AND of all event_caps for events in this group. */
 705         int                             group_caps;
 706
 707         unsigned int                    group_generation;
 708         struct perf_event               *group_leader;
 709         /*
 710          * event->pmu will always point to pmu in which this event belongs.
 711          * Whereas event->pmu_ctx->pmu may point to other pmu when group of
 712          * different pmu events is created.
 713          */
 714         struct pmu                      *pmu;
 715         void                            *pmu_private;
 716
 717         enum perf_event_state           state;
 718         unsigned int                    attach_state;
 719         local64_t                       count;
 720         atomic64_t                      child_count;
 721
 722         /*
 723          * These are the total time in nanoseconds that the event
 724          * has been enabled (i.e. eligible to run, and the task has
 725          * been scheduled in, if this is a per-task event)
 726          * and running (scheduled onto the CPU), respectively.
 727          */
 728         u64                             total_time_enabled;
 729         u64                             total_time_running;
 730         u64                             tstamp;
 731
 732         struct perf_event_attr          attr;
 733         u16                             header_size;
 734         u16                             id_header_size;
 735         u16                             read_size;
 736         struct hw_perf_event            hw;
 737
 738         struct perf_event_context       *ctx;
 739         /*
 740          * event->pmu_ctx points to perf_event_pmu_context in which the event
 741          * is added. This pmu_ctx can be of other pmu for sw event when that
 742          * sw event is part of a group which also contains non-sw events.
 743          */
 744         struct perf_event_pmu_context   *pmu_ctx;
 745         atomic_long_t                   refcount;
 746
 747         /*
 748          * These accumulate total time (in nanoseconds) that children
 749          * events have been enabled and running, respectively.
 750          */
 751         atomic64_t                      child_total_time_enabled;
 752         atomic64_t                      child_total_time_running;
 753
 754         /*
 755          * Protect attach/detach and child_list:
 756          */
 757         struct mutex                    child_mutex;
 758         struct list_head                child_list;
 759         struct perf_event               *parent;
 760
 761         int                             oncpu;
 762         int                             cpu;
 763
 764         struct list_head                owner_entry;
 765         struct task_struct              *owner;
 766
 767         /* mmap bits */
 768         struct mutex                    mmap_mutex;
 769         atomic_t                        mmap_count;
 770
 771         struct perf_buffer              *rb;
 772         struct list_head                rb_entry;
 773         unsigned long                   rcu_batches;
 774         int                             rcu_pending;
 775
 776         /* poll related */
 777         wait_queue_head_t               waitq;
 778         struct fasync_struct            *fasync;
 779
 780         /* delayed work for NMIs and such */
 781         unsigned int                    pending_wakeup;
 782         unsigned int                    pending_kill;
 783         unsigned int                    pending_disable;
 784         unsigned int                    pending_sigtrap;
 785         unsigned long                   pending_addr;   /* SIGTRAP */
 786         struct irq_work                 pending_irq;
 787         struct callback_head            pending_task;
 788         unsigned int                    pending_work;
 789
 790         atomic_t                        event_limit;
 791
 792         /* address range filters */
 793         struct perf_addr_filters_head   addr_filters;
 794         /* vma address array for file-based filders */
 795         struct perf_addr_filter_range   *addr_filter_ranges;
 796         unsigned long                   addr_filters_gen;
 797
 798         /* for aux_output events */
 799         struct perf_event               *aux_event;
 800
 801         void (*destroy)(struct perf_event *);
 802         struct rcu_head                 rcu_head;
 803
 804         struct pid_namespace            *ns;
 805         u64                             id;
 806
 807         atomic64_t                      lost_samples;
 808
 809         u64                             (*clock)(void);
 810         perf_overflow_handler_t         overflow_handler;
 811         void                            *overflow_handler_context;
 812         struct bpf_prog                 *prog;
 813         u64                             bpf_cookie;
 814
 815 #ifdef CONFIG_EVENT_TRACING
 816         struct trace_event_call         *tp_event;
 817         struct event_filter             *filter;
 818 #ifdef CONFIG_FUNCTION_TRACER
 819         struct ftrace_ops               ftrace_ops;
 820 #endif
 821 #endif
 822
 823 #ifdef CONFIG_CGROUP_PERF
 824         struct perf_cgroup              *cgrp; /* cgroup event is attach to */
 825 #endif
 826
 827 #ifdef CONFIG_SECURITY
 828         void *security;
 829 #endif
 830         struct list_head                sb_list;
 831
 832         /*
 833          * Certain events gets forwarded to another pmu internally by over-
 834          * writing kernel copy of event->attr.type without user being aware
 835          * of it. event->orig_type contains original 'type' requested by
 836          * user.
 837          */
 838         __u32                           orig_type;
 839 #endif /* CONFIG_PERF_EVENTS */
 840 };
 841
 842 /*
 843  *           ,-----------------------[1:n]------------------------.
 844  *           V                                                    V
 845  * perf_event_context <-[1:n]-> perf_event_pmu_context <-[1:n]- perf_event
 846  *                                        |                       |
 847  *                                        `--[n:1]-> pmu <-[1:n]--'
 848  *
 849  *
 850  * struct perf_event_pmu_context  lifetime is refcount based and RCU freed
 851  * (similar to perf_event_context). Locking is as if it were a member of
 852  * perf_event_context; specifically:
 853  *
 854  *   modification, both: ctx->mutex && ctx->lock
 855  *   reading, either:    ctx->mutex || ctx->lock
 856  *
 857  * There is one exception to this; namely put_pmu_ctx() isn't always called
 858  * with ctx->mutex held; this means that as long as we can guarantee the epc
 859  * has events the above rules hold.
 860  *
 861  * Specificially, sys_perf_event_open()'s group_leader case depends on
 862  * ctx->mutex pinning the configuration. Since we hold a reference on
 863  * group_leader (through the filedesc) it can't go away, therefore it's
 864  * associated pmu_ctx must exist and cannot change due to ctx->mutex.
 865  *
 866  * perf_event holds a refcount on perf_event_context
 867  * perf_event holds a refcount on perf_event_pmu_context
 868  */
 869 struct perf_event_pmu_context {
 870         struct pmu                      *pmu;
 871         struct perf_event_context       *ctx;
 872
 873         struct list_head                pmu_ctx_entry;
 874
 875         struct list_head                pinned_active;
 876         struct list_head                flexible_active;
 877
 878         /* Used to avoid freeing per-cpu perf_event_pmu_context */
 879         unsigned int                    embedded : 1;
 880
 881         unsigned int                    nr_events;
 882         unsigned int                    nr_cgroups;
 883         unsigned int                    nr_freq;
 884
 885         atomic_t                        refcount; /* event <-> epc */
 886         struct rcu_head                 rcu_head;
 887
 888         void                            *task_ctx_data; /* pmu specific data */
 889         /*
 890          * Set when one or more (plausibly active) event can't be scheduled
 891          * due to pmu overcommit or pmu constraints, except tolerant to
 892          * events not necessary to be active due to scheduling constraints,
 893          * such as cgroups.
 894          */
 895         int                             rotate_necessary;
 896 };
 897
 898 static inline bool perf_pmu_ctx_is_active(struct perf_event_pmu_context *epc)
 899 {
 900         return !list_empty(&epc->flexible_active) || !list_empty(&epc->pinned_active);
 901 }
 902
 903 struct perf_event_groups {
 904         struct rb_root  tree;
 905         u64             index;
 906 };
 907
 908
 909 /**
 910  * struct perf_event_context - event context structure
 911  *
 912  * Used as a container for task events and CPU events as well:
 913  */
 914 struct perf_event_context {
 915         /*
 916          * Protect the states of the events in the list,
 917          * nr_active, and the list:
 918          */
 919         raw_spinlock_t                  lock;
 920         /*
 921          * Protect the list of events.  Locking either mutex or lock
 922          * is sufficient to ensure the list doesn't change; to change
 923          * the list you need to lock both the mutex and the spinlock.
 924          */
 925         struct mutex                    mutex;
 926
 927         struct list_head                pmu_ctx_list;
 928         struct perf_event_groups        pinned_groups;
 929         struct perf_event_groups        flexible_groups;
 930         struct list_head                event_list;
 931
 932         int                             nr_events;
 933         int                             nr_user;
 934         int                             is_active;
 935
 936         int                             nr_task_data;
 937         int                             nr_stat;
 938         int                             nr_freq;
 939         int                             rotate_disable;
 940
 941         refcount_t                      refcount; /* event <-> ctx */
 942         struct task_struct              *task;
 943
 944         /*
 945          * Context clock, runs when context enabled.
 946          */
 947         u64                             time;
 948         u64                             timestamp;
 949         u64                             timeoffset;
 950
 951         /*
 952          * These fields let us detect when two contexts have both
 953          * been cloned (inherited) from a common ancestor.
 954          */
 955         struct perf_event_context       *parent_ctx;
 956         u64                             parent_gen;
 957         u64                             generation;
 958         int                             pin_count;
 959 #ifdef CONFIG_CGROUP_PERF
 960         int                             nr_cgroups;      /* cgroup evts */
 961 #endif
 962         struct rcu_head                 rcu_head;
 963
 964         /*
 965          * Sum (event->pending_sigtrap + event->pending_work)
 966          *
 967          * The SIGTRAP is targeted at ctx->task, as such it won't do changing
 968          * that until the signal is delivered.
 969          */
 970         local_t                         nr_pending;
 971 };
 972
 973 /*
 974  * Number of contexts where an event can trigger:
 975  *      task, softirq, hardirq, nmi.
 976  */
 977 #define PERF_NR_CONTEXTS        4
 978
 979 struct perf_cpu_pmu_context {
 980         struct perf_event_pmu_context   epc;
 981         struct perf_event_pmu_context   *task_epc;
 982
 983         struct list_head                sched_cb_entry;
 984         int                             sched_cb_usage;
 985
 986         int                             active_oncpu;
 987         int                             exclusive;
 988
 989         raw_spinlock_t                  hrtimer_lock;
 990         struct hrtimer                  hrtimer;
 991         ktime_t                         hrtimer_interval;
 992         unsigned int                    hrtimer_active;
 993 };
 994
 995 /**
 996  * struct perf_event_cpu_context - per cpu event context structure
 997  */
 998 struct perf_cpu_context {
 999         struct perf_event_context       ctx;
1000         struct perf_event_context       *task_ctx;
1001         int                             online;
1002
1003 #ifdef CONFIG_CGROUP_PERF
1004         struct perf_cgroup              *cgrp;
1005 #endif
1006
1007         /*
1008          * Per-CPU storage for iterators used in visit_groups_merge. The default
1009          * storage is of size 2 to hold the CPU and any CPU event iterators.
1010          */
1011         int                             heap_size;
1012         struct perf_event               **heap;
1013         struct perf_event               *heap_default[2];
1014 };
1015
1016 struct perf_output_handle {
1017         struct perf_event               *event;
1018         struct perf_buffer              *rb;
1019         unsigned long                   wakeup;
1020         unsigned long                   size;
1021         u64                             aux_flags;
1022         union {
1023                 void                    *addr;
1024                 unsigned long           head;
1025         };
1026         int                             page;
1027 };
1028
1029 struct bpf_perf_event_data_kern {
1030         bpf_user_pt_regs_t *regs;
1031         struct perf_sample_data *data;
1032         struct perf_event *event;
1033 };
1034
1035 #ifdef CONFIG_CGROUP_PERF
1036
1037 /*
1038  * perf_cgroup_info keeps track of time_enabled for a cgroup.
1039  * This is a per-cpu dynamically allocated data structure.
1040  */
1041 struct perf_cgroup_info {
1042         u64                             time;
1043         u64                             timestamp;
1044         u64                             timeoffset;
1045         int                             active;
1046 };
1047
1048 struct perf_cgroup {
1049         struct cgroup_subsys_state      css;
1050         struct perf_cgroup_info __percpu *info;
1051 };
1052
1053 /*
1054  * Must ensure cgroup is pinned (css_get) before calling
1055  * this function. In other words, we cannot call this function
1056  * if there is no cgroup event for the current CPU context.
1057  */
1058 static inline struct perf_cgroup *
1059 perf_cgroup_from_task(struct task_struct *task, struct perf_event_context *ctx)
1060 {
1061         return container_of(task_css_check(task, perf_event_cgrp_id,
1062                                            ctx ? lockdep_is_held(&ctx->lock)
1063                                                : true),
1064                             struct perf_cgroup, css);
1065 }
1066 #endif /* CONFIG_CGROUP_PERF */
1067
1068 #ifdef CONFIG_PERF_EVENTS
1069
1070 extern struct perf_event_context *perf_cpu_task_ctx(void);
1071
1072 extern void *perf_aux_output_begin(struct perf_output_handle *handle,
1073                                    struct perf_event *event);
1074 extern void perf_aux_output_end(struct perf_output_handle *handle,
1075                                 unsigned long size);
1076 extern int perf_aux_output_skip(struct perf_output_handle *handle,
1077                                 unsigned long size);
1078 extern void *perf_get_aux(struct perf_output_handle *handle);
1079 extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
1080 extern void perf_event_itrace_started(struct perf_event *event);
1081
1082 extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
1083 extern void perf_pmu_unregister(struct pmu *pmu);
1084
1085 extern void __perf_event_task_sched_in(struct task_struct *prev,
1086                                        struct task_struct *task);
1087 extern void __perf_event_task_sched_out(struct task_struct *prev,
1088                                         struct task_struct *next);
1089 extern int perf_event_init_task(struct task_struct *child, u64 clone_flags);
1090 extern void perf_event_exit_task(struct task_struct *child);
1091 extern void perf_event_free_task(struct task_struct *task);
1092 extern void perf_event_delayed_put(struct task_struct *task);
1093 extern struct file *perf_event_get(unsigned int fd);
1094 extern const struct perf_event *perf_get_event(struct file *file);
1095 extern const struct perf_event_attr *perf_event_attrs(struct perf_event *event);
1096 extern void perf_event_print_debug(void);
1097 extern void perf_pmu_disable(struct pmu *pmu);
1098 extern void perf_pmu_enable(struct pmu *pmu);
1099 extern void perf_sched_cb_dec(struct pmu *pmu);
1100 extern void perf_sched_cb_inc(struct pmu *pmu);
1101 extern int perf_event_task_disable(void);
1102 extern int perf_event_task_enable(void);
1103
1104 extern void perf_pmu_resched(struct pmu *pmu);
1105
1106 extern int perf_event_refresh(struct perf_event *event, int refresh);
1107 extern void perf_event_update_userpage(struct perf_event *event);
1108 extern int perf_event_release_kernel(struct perf_event *event);
1109 extern struct perf_event *
1110 perf_event_create_kernel_counter(struct perf_event_attr *attr,
1111                                 int cpu,
1112                                 struct task_struct *task,
1113                                 perf_overflow_handler_t callback,
1114                                 void *context);
1115 extern void perf_pmu_migrate_context(struct pmu *pmu,
1116                                 int src_cpu, int dst_cpu);
1117 int perf_event_read_local(struct perf_event *event, u64 *value,
1118                           u64 *enabled, u64 *running);
1119 extern u64 perf_event_read_value(struct perf_event *event,
1120                                  u64 *enabled, u64 *running);
1121
1122 extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, struct pt_regs *regs);
1123
1124 static inline bool branch_sample_no_flags(const struct perf_event *event)
1125 {
1126         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_NO_FLAGS;
1127 }
1128
1129 static inline bool branch_sample_no_cycles(const struct perf_event *event)
1130 {
1131         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_NO_CYCLES;
1132 }
1133
1134 static inline bool branch_sample_type(const struct perf_event *event)
1135 {
1136         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_TYPE_SAVE;
1137 }
1138
1139 static inline bool branch_sample_hw_index(const struct perf_event *event)
1140 {
1141         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX;
1142 }
1143
1144 static inline bool branch_sample_priv(const struct perf_event *event)
1145 {
1146         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_PRIV_SAVE;
1147 }
1148
1149 static inline bool branch_sample_counters(const struct perf_event *event)
1150 {
1151         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS;
1152 }
1153
1154 static inline bool branch_sample_call_stack(const struct perf_event *event)
1155 {
1156         return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK;
1157 }
1158
1159 struct perf_sample_data {
1160         /*
1161          * Fields set by perf_sample_data_init() unconditionally,
1162          * group so as to minimize the cachelines touched.
1163          */
1164         u64                             sample_flags;
1165         u64                             period;
1166         u64                             dyn_size;
1167
1168         /*
1169          * Fields commonly set by __perf_event_header__init_id(),
1170          * group so as to minimize the cachelines touched.
1171          */
1172         u64                             type;
1173         struct {
1174                 u32     pid;
1175                 u32     tid;
1176         }                               tid_entry;
1177         u64                             time;
1178         u64                             id;
1179         struct {
1180                 u32     cpu;
1181                 u32     reserved;
1182         }                               cpu_entry;
1183
1184         /*
1185          * The other fields, optionally {set,used} by
1186          * perf_{prepare,output}_sample().
1187          */
1188         u64                             ip;
1189         struct perf_callchain_entry     *callchain;
1190         struct perf_raw_record          *raw;
1191         struct perf_branch_stack        *br_stack;
1192         u64                             *br_stack_cntr;
1193         union perf_sample_weight        weight;
1194         union  perf_mem_data_src        data_src;
1195         u64                             txn;
1196
1197         struct perf_regs                regs_user;
1198         struct perf_regs                regs_intr;
1199         u64                             stack_user_size;
1200
1201         u64                             stream_id;
1202         u64                             cgroup;
1203         u64                             addr;
1204         u64                             phys_addr;
1205         u64                             data_page_size;
1206         u64                             code_page_size;
1207         u64                             aux_size;
1208 } ____cacheline_aligned;
1209
1210 /* default value for data source */
1211 #define PERF_MEM_NA (PERF_MEM_S(OP, NA)   |\
1212                     PERF_MEM_S(LVL, NA)   |\
1213                     PERF_MEM_S(SNOOP, NA) |\
1214                     PERF_MEM_S(LOCK, NA)  |\
1215                     PERF_MEM_S(TLB, NA)   |\
1216                     PERF_MEM_S(LVLNUM, NA))
1217
1218 static inline void perf_sample_data_init(struct perf_sample_data *data,
1219                                          u64 addr, u64 period)
1220 {
1221         /* remaining struct members initialized in perf_prepare_sample() */
1222         data->sample_flags = PERF_SAMPLE_PERIOD;
1223         data->period = period;
1224         data->dyn_size = 0;
1225
1226         if (addr) {
1227                 data->addr = addr;
1228                 data->sample_flags |= PERF_SAMPLE_ADDR;
1229         }
1230 }
1231
1232 static inline void perf_sample_save_callchain(struct perf_sample_data *data,
1233                                               struct perf_event *event,
1234                                               struct pt_regs *regs)
1235 {
1236         int size = 1;
1237
1238         data->callchain = perf_callchain(event, regs);
1239         size += data->callchain->nr;
1240
1241         data->dyn_size += size * sizeof(u64);
1242         data->sample_flags |= PERF_SAMPLE_CALLCHAIN;
1243 }
1244
1245 static inline void perf_sample_save_raw_data(struct perf_sample_data *data,
1246                                              struct perf_raw_record *raw)
1247 {
1248         struct perf_raw_frag *frag = &raw->frag;
1249         u32 sum = 0;
1250         int size;
1251
1252         do {
1253                 sum += frag->size;
1254                 if (perf_raw_frag_last(frag))
1255                         break;
1256                 frag = frag->next;
1257         } while (1);
1258
1259         size = round_up(sum + sizeof(u32), sizeof(u64));
1260         raw->size = size - sizeof(u32);
1261         frag->pad = raw->size - sum;
1262
1263         data->raw = raw;
1264         data->dyn_size += size;
1265         data->sample_flags |= PERF_SAMPLE_RAW;
1266 }
1267
1268 static inline void perf_sample_save_brstack(struct perf_sample_data *data,
1269                                             struct perf_event *event,
1270                                             struct perf_branch_stack *brs,
1271                                             u64 *brs_cntr)
1272 {
1273         int size = sizeof(u64); /* nr */
1274
1275         if (branch_sample_hw_index(event))
1276                 size += sizeof(u64);
1277         size += brs->nr * sizeof(struct perf_branch_entry);
1278
1279         /*
1280          * The extension space for counters is appended after the
1281          * struct perf_branch_stack. It is used to store the occurrences
1282          * of events of each branch.
1283          */
1284         if (brs_cntr)
1285                 size += brs->nr * sizeof(u64);
1286
1287         data->br_stack = brs;
1288         data->br_stack_cntr = brs_cntr;
1289         data->dyn_size += size;
1290         data->sample_flags |= PERF_SAMPLE_BRANCH_STACK;
1291 }
1292
1293 static inline u32 perf_sample_data_size(struct perf_sample_data *data,
1294                                         struct perf_event *event)
1295 {
1296         u32 size = sizeof(struct perf_event_header);
1297
1298         size += event->header_size + event->id_header_size;
1299         size += data->dyn_size;
1300
1301         return size;
1302 }
1303
1304 /*
1305  * Clear all bitfields in the perf_branch_entry.
1306  * The to and from fields are not cleared because they are
1307  * systematically modified by caller.
1308  */
1309 static inline void perf_clear_branch_entry_bitfields(struct perf_branch_entry *br)
1310 {
1311         br->mispred = 0;
1312         br->predicted = 0;
1313         br->in_tx = 0;
1314         br->abort = 0;
1315         br->cycles = 0;
1316         br->type = 0;
1317         br->spec = PERF_BR_SPEC_NA;
1318         br->reserved = 0;
1319 }
1320
1321 extern void perf_output_sample(struct perf_output_handle *handle,
1322                                struct perf_event_header *header,
1323                                struct perf_sample_data *data,
1324                                struct perf_event *event);
1325 extern void perf_prepare_sample(struct perf_sample_data *data,
1326                                 struct perf_event *event,
1327                                 struct pt_regs *regs);
1328 extern void perf_prepare_header(struct perf_event_header *header,
1329                                 struct perf_sample_data *data,
1330                                 struct perf_event *event,
1331                                 struct pt_regs *regs);
1332
1333 extern int perf_event_overflow(struct perf_event *event,
1334                                  struct perf_sample_data *data,
1335                                  struct pt_regs *regs);
1336
1337 extern void perf_event_output_forward(struct perf_event *event,
1338                                      struct perf_sample_data *data,
1339                                      struct pt_regs *regs);
1340 extern void perf_event_output_backward(struct perf_event *event,
1341                                        struct perf_sample_data *data,
1342                                        struct pt_regs *regs);
1343 extern int perf_event_output(struct perf_event *event,
1344                              struct perf_sample_data *data,
1345                              struct pt_regs *regs);
1346
1347 static inline bool
1348 is_default_overflow_handler(struct perf_event *event)
1349 {
1350         perf_overflow_handler_t overflow_handler = event->overflow_handler;
1351
1352         if (likely(overflow_handler == perf_event_output_forward))
1353                 return true;
1354         if (unlikely(overflow_handler == perf_event_output_backward))
1355                 return true;
1356         return false;
1357 }
1358
1359 extern void
1360 perf_event_header__init_id(struct perf_event_header *header,
1361                            struct perf_sample_data *data,
1362                            struct perf_event *event);
1363 extern void
1364 perf_event__output_id_sample(struct perf_event *event,
1365                              struct perf_output_handle *handle,
1366                              struct perf_sample_data *sample);
1367
1368 extern void
1369 perf_log_lost_samples(struct perf_event *event, u64 lost);
1370
1371 static inline bool event_has_any_exclude_flag(struct perf_event *event)
1372 {
1373         struct perf_event_attr *attr = &event->attr;
1374
1375         return attr->exclude_idle || attr->exclude_user ||
1376                attr->exclude_kernel || attr->exclude_hv ||
1377                attr->exclude_guest || attr->exclude_host;
1378 }
1379
1380 static inline bool is_sampling_event(struct perf_event *event)
1381 {
1382         return event->attr.sample_period != 0;
1383 }
1384
1385 /*
1386  * Return 1 for a software event, 0 for a hardware event
1387  */
1388 static inline int is_software_event(struct perf_event *event)
1389 {
1390         return event->event_caps & PERF_EV_CAP_SOFTWARE;
1391 }
1392
1393 /*
1394  * Return 1 for event in sw context, 0 for event in hw context
1395  */
1396 static inline int in_software_context(struct perf_event *event)
1397 {
1398         return event->pmu_ctx->pmu->task_ctx_nr == perf_sw_context;
1399 }
1400
1401 static inline int is_exclusive_pmu(struct pmu *pmu)
1402 {
1403         return pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE;
1404 }
1405
1406 extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
1407
1408 extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
1409 extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
1410
1411 #ifndef perf_arch_fetch_caller_regs
1412 static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
1413 #endif
1414
1415 /*
1416  * When generating a perf sample in-line, instead of from an interrupt /
1417  * exception, we lack a pt_regs. This is typically used from software events
1418  * like: SW_CONTEXT_SWITCHES, SW_MIGRATIONS and the tie-in with tracepoints.
1419  *
1420  * We typically don't need a full set, but (for x86) do require:
1421  * - ip for PERF_SAMPLE_IP
1422  * - cs for user_mode() tests
1423  * - sp for PERF_SAMPLE_CALLCHAIN
1424  * - eflags for MISC bits and CALLCHAIN (see: perf_hw_regs())
1425  *
1426  * NOTE: assumes @regs is otherwise already 0 filled; this is important for
1427  * things like PERF_SAMPLE_REGS_INTR.
1428  */
1429 static inline void perf_fetch_caller_regs(struct pt_regs *regs)
1430 {
1431         perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
1432 }
1433
1434 static __always_inline void
1435 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
1436 {
1437         if (static_key_false(&perf_swevent_enabled[event_id]))
1438                 __perf_sw_event(event_id, nr, regs, addr);
1439 }
1440
1441 DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);
1442
1443 /*
1444  * 'Special' version for the scheduler, it hard assumes no recursion,
1445  * which is guaranteed by us not actually scheduling inside other swevents
1446  * because those disable preemption.
1447  */
1448 static __always_inline void __perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
1449 {
1450         struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
1451
1452         perf_fetch_caller_regs(regs);
1453         ___perf_sw_event(event_id, nr, regs, addr);
1454 }
1455
1456 extern struct static_key_false perf_sched_events;
1457
1458 static __always_inline bool __perf_sw_enabled(int swevt)
1459 {
1460         return static_key_false(&perf_swevent_enabled[swevt]);
1461 }
1462
1463 static inline void perf_event_task_migrate(struct task_struct *task)
1464 {
1465         if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS))
1466                 task->sched_migrated = 1;
1467 }
1468
1469 static inline void perf_event_task_sched_in(struct task_struct *prev,
1470                                             struct task_struct *task)
1471 {
1472         if (static_branch_unlikely(&perf_sched_events))
1473                 __perf_event_task_sched_in(prev, task);
1474
1475         if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS) &&
1476             task->sched_migrated) {
1477                 __perf_sw_event_sched(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 0);
1478                 task->sched_migrated = 0;
1479         }
1480 }
1481
1482 static inline void perf_event_task_sched_out(struct task_struct *prev,
1483                                              struct task_struct *next)
1484 {
1485         if (__perf_sw_enabled(PERF_COUNT_SW_CONTEXT_SWITCHES))
1486                 __perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);
1487
1488 #ifdef CONFIG_CGROUP_PERF
1489         if (__perf_sw_enabled(PERF_COUNT_SW_CGROUP_SWITCHES) &&
1490             perf_cgroup_from_task(prev, NULL) !=
1491             perf_cgroup_from_task(next, NULL))
1492                 __perf_sw_event_sched(PERF_COUNT_SW_CGROUP_SWITCHES, 1, 0);
1493 #endif
1494
1495         if (static_branch_unlikely(&perf_sched_events))
1496                 __perf_event_task_sched_out(prev, next);
1497 }
1498
1499 extern void perf_event_mmap(struct vm_area_struct *vma);
1500
1501 extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1502                                bool unregister, const char *sym);
1503 extern void perf_event_bpf_event(struct bpf_prog *prog,
1504                                  enum perf_bpf_event_type type,
1505                                  u16 flags);
1506
1507 #ifdef CONFIG_GUEST_PERF_EVENTS
1508 extern struct perf_guest_info_callbacks __rcu *perf_guest_cbs;
1509
1510 DECLARE_STATIC_CALL(__perf_guest_state, *perf_guest_cbs->state);
1511 DECLARE_STATIC_CALL(__perf_guest_get_ip, *perf_guest_cbs->get_ip);
1512 DECLARE_STATIC_CALL(__perf_guest_handle_intel_pt_intr, *perf_guest_cbs->handle_intel_pt_intr);
1513
1514 static inline unsigned int perf_guest_state(void)
1515 {
1516         return static_call(__perf_guest_state)();
1517 }
1518 static inline unsigned long perf_guest_get_ip(void)
1519 {
1520         return static_call(__perf_guest_get_ip)();
1521 }
1522 static inline unsigned int perf_guest_handle_intel_pt_intr(void)
1523 {
1524         return static_call(__perf_guest_handle_intel_pt_intr)();
1525 }
1526 extern void perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs);
1527 extern void perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs);
1528 #else
1529 static inline unsigned int perf_guest_state(void)                { return 0; }
1530 static inline unsigned long perf_guest_get_ip(void)              { return 0; }
1531 static inline unsigned int perf_guest_handle_intel_pt_intr(void) { return 0; }
1532 #endif /* CONFIG_GUEST_PERF_EVENTS */
1533
1534 extern void perf_event_exec(void);
1535 extern void perf_event_comm(struct task_struct *tsk, bool exec);
1536 extern void perf_event_namespaces(struct task_struct *tsk);
1537 extern void perf_event_fork(struct task_struct *tsk);
1538 extern void perf_event_text_poke(const void *addr,
1539                                  const void *old_bytes, size_t old_len,
1540                                  const void *new_bytes, size_t new_len);
1541
1542 /* Callchains */
1543 DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
1544
1545 extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1546 extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
1547 extern struct perf_callchain_entry *
1548 get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
1549                    u32 max_stack, bool crosstask, bool add_mark);
1550 extern int get_callchain_buffers(int max_stack);
1551 extern void put_callchain_buffers(void);
1552 extern struct perf_callchain_entry *get_callchain_entry(int *rctx);
1553 extern void put_callchain_entry(int rctx);
1554
1555 extern int sysctl_perf_event_max_stack;
1556 extern int sysctl_perf_event_max_contexts_per_stack;
1557
1558 static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
1559 {
1560         if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
1561                 struct perf_callchain_entry *entry = ctx->entry;
1562                 entry->ip[entry->nr++] = ip;
1563                 ++ctx->contexts;
1564                 return 0;
1565         } else {
1566                 ctx->contexts_maxed = true;
1567                 return -1; /* no more room, stop walking the stack */
1568         }
1569 }
1570
1571 static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
1572 {
1573         if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
1574                 struct perf_callchain_entry *entry = ctx->entry;
1575                 entry->ip[entry->nr++] = ip;
1576                 ++ctx->nr;
1577                 return 0;
1578         } else {
1579                 return -1; /* no more room, stop walking the stack */
1580         }
1581 }
1582
1583 extern int sysctl_perf_event_paranoid;
1584 extern int sysctl_perf_event_mlock;
1585 extern int sysctl_perf_event_sample_rate;
1586 extern int sysctl_perf_cpu_time_max_percent;
1587
1588 extern void perf_sample_event_took(u64 sample_len_ns);
1589
1590 int perf_event_max_sample_rate_handler(struct ctl_table *table, int write,
1591                 void *buffer, size_t *lenp, loff_t *ppos);
1592 int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
1593                 void *buffer, size_t *lenp, loff_t *ppos);
1594 int perf_event_max_stack_handler(struct ctl_table *table, int write,
1595                 void *buffer, size_t *lenp, loff_t *ppos);
1596
1597 /* Access to perf_event_open(2) syscall. */
1598 #define PERF_SECURITY_OPEN              0
1599
1600 /* Finer grained perf_event_open(2) access control. */
1601 #define PERF_SECURITY_CPU               1
1602 #define PERF_SECURITY_KERNEL            2
1603 #define PERF_SECURITY_TRACEPOINT        3
1604
1605 static inline int perf_is_paranoid(void)
1606 {
1607         return sysctl_perf_event_paranoid > -1;
1608 }
1609
1610 static inline int perf_allow_kernel(struct perf_event_attr *attr)
1611 {
1612         if (sysctl_perf_event_paranoid > 1 && !perfmon_capable())
1613                 return -EACCES;
1614
1615         return security_perf_event_open(attr, PERF_SECURITY_KERNEL);
1616 }
1617
1618 static inline int perf_allow_cpu(struct perf_event_attr *attr)
1619 {
1620         if (sysctl_perf_event_paranoid > 0 && !perfmon_capable())
1621                 return -EACCES;
1622
1623         return security_perf_event_open(attr, PERF_SECURITY_CPU);
1624 }
1625
1626 static inline int perf_allow_tracepoint(struct perf_event_attr *attr)
1627 {
1628         if (sysctl_perf_event_paranoid > -1 && !perfmon_capable())
1629                 return -EPERM;
1630
1631         return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT);
1632 }
1633
1634 extern void perf_event_init(void);
1635 extern void perf_tp_event(u16 event_type, u64 count, void *record,
1636                           int entry_size, struct pt_regs *regs,
1637                           struct hlist_head *head, int rctx,
1638                           struct task_struct *task);
1639 extern void perf_bp_event(struct perf_event *event, void *data);
1640
1641 #ifndef perf_misc_flags
1642 # define perf_misc_flags(regs) \
1643                 (user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
1644 # define perf_instruction_pointer(regs) instruction_pointer(regs)
1645 #endif
1646 #ifndef perf_arch_bpf_user_pt_regs
1647 # define perf_arch_bpf_user_pt_regs(regs) regs
1648 #endif
1649
1650 static inline bool has_branch_stack(struct perf_event *event)
1651 {
1652         return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
1653 }
1654
1655 static inline bool needs_branch_stack(struct perf_event *event)
1656 {
1657         return event->attr.branch_sample_type != 0;
1658 }
1659
1660 static inline bool has_aux(struct perf_event *event)
1661 {
1662         return event->pmu->setup_aux;
1663 }
1664
1665 static inline bool is_write_backward(struct perf_event *event)
1666 {
1667         return !!event->attr.write_backward;
1668 }
1669
1670 static inline bool has_addr_filter(struct perf_event *event)
1671 {
1672         return event->pmu->nr_addr_filters;
1673 }
1674
1675 /*
1676  * An inherited event uses parent's filters
1677  */
1678 static inline struct perf_addr_filters_head *
1679 perf_event_addr_filters(struct perf_event *event)
1680 {
1681         struct perf_addr_filters_head *ifh = &event->addr_filters;
1682
1683         if (event->parent)
1684                 ifh = &event->parent->addr_filters;
1685
1686         return ifh;
1687 }
1688
1689 static inline struct fasync_struct **perf_event_fasync(struct perf_event *event)
1690 {
1691         /* Only the parent has fasync state */
1692         if (event->parent)
1693                 event = event->parent;
1694         return &event->fasync;
1695 }
1696
1697 extern void perf_event_addr_filters_sync(struct perf_event *event);
1698 extern void perf_report_aux_output_id(struct perf_event *event, u64 hw_id);
1699
1700 extern int perf_output_begin(struct perf_output_handle *handle,
1701                              struct perf_sample_data *data,
1702                              struct perf_event *event, unsigned int size);
1703 extern int perf_output_begin_forward(struct perf_output_handle *handle,
1704                                      struct perf_sample_data *data,
1705                                      struct perf_event *event,
1706                                      unsigned int size);
1707 extern int perf_output_begin_backward(struct perf_output_handle *handle,
1708                                       struct perf_sample_data *data,
1709                                       struct perf_event *event,
1710                                       unsigned int size);
1711
1712 extern void perf_output_end(struct perf_output_handle *handle);
1713 extern unsigned int perf_output_copy(struct perf_output_handle *handle,
1714                              const void *buf, unsigned int len);
1715 extern unsigned int perf_output_skip(struct perf_output_handle *handle,
1716                                      unsigned int len);
1717 extern long perf_output_copy_aux(struct perf_output_handle *aux_handle,
1718                                  struct perf_output_handle *handle,
1719                                  unsigned long from, unsigned long to);
1720 extern int perf_swevent_get_recursion_context(void);
1721 extern void perf_swevent_put_recursion_context(int rctx);
1722 extern u64 perf_swevent_set_period(struct perf_event *event);
1723 extern void perf_event_enable(struct perf_event *event);
1724 extern void perf_event_disable(struct perf_event *event);
1725 extern void perf_event_disable_local(struct perf_event *event);
1726 extern void perf_event_disable_inatomic(struct perf_event *event);
1727 extern void perf_event_task_tick(void);
1728 extern int perf_event_account_interrupt(struct perf_event *event);
1729 extern int perf_event_period(struct perf_event *event, u64 value);
1730 extern u64 perf_event_pause(struct perf_event *event, bool reset);
1731 #else /* !CONFIG_PERF_EVENTS: */
1732 static inline void *
1733 perf_aux_output_begin(struct perf_output_handle *handle,
1734                       struct perf_event *event)                         { return NULL; }
1735 static inline void
1736 perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
1737                                                                         { }
1738 static inline int
1739 perf_aux_output_skip(struct perf_output_handle *handle,
1740                      unsigned long size)                                { return -EINVAL; }
1741 static inline void *
1742 perf_get_aux(struct perf_output_handle *handle)                         { return NULL; }
1743 static inline void
1744 perf_event_task_migrate(struct task_struct *task)                       { }
1745 static inline void
1746 perf_event_task_sched_in(struct task_struct *prev,
1747                          struct task_struct *task)                      { }
1748 static inline void
1749 perf_event_task_sched_out(struct task_struct *prev,
1750                           struct task_struct *next)                     { }
1751 static inline int perf_event_init_task(struct task_struct *child,
1752                                        u64 clone_flags)                 { return 0; }
1753 static inline void perf_event_exit_task(struct task_struct *child)      { }
1754 static inline void perf_event_free_task(struct task_struct *task)       { }
1755 static inline void perf_event_delayed_put(struct task_struct *task)     { }
1756 static inline struct file *perf_event_get(unsigned int fd)      { return ERR_PTR(-EINVAL); }
1757 static inline const struct perf_event *perf_get_event(struct file *file)
1758 {
1759         return ERR_PTR(-EINVAL);
1760 }
1761 static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
1762 {
1763         return ERR_PTR(-EINVAL);
1764 }
1765 static inline int perf_event_read_local(struct perf_event *event, u64 *value,
1766                                         u64 *enabled, u64 *running)
1767 {
1768         return -EINVAL;
1769 }
1770 static inline void perf_event_print_debug(void)                         { }
1771 static inline int perf_event_task_disable(void)                         { return -EINVAL; }
1772 static inline int perf_event_task_enable(void)                          { return -EINVAL; }
1773 static inline int perf_event_refresh(struct perf_event *event, int refresh)
1774 {
1775         return -EINVAL;
1776 }
1777
1778 static inline void
1779 perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)     { }
1780 static inline void
1781 perf_bp_event(struct perf_event *event, void *data)                     { }
1782
1783 static inline void perf_event_mmap(struct vm_area_struct *vma)          { }
1784
1785 typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data);
1786 static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
1787                                       bool unregister, const char *sym) { }
1788 static inline void perf_event_bpf_event(struct bpf_prog *prog,
1789                                         enum perf_bpf_event_type type,
1790                                         u16 flags)                      { }
1791 static inline void perf_event_exec(void)                                { }
1792 static inline void perf_event_comm(struct task_struct *tsk, bool exec)  { }
1793 static inline void perf_event_namespaces(struct task_struct *tsk)       { }
1794 static inline void perf_event_fork(struct task_struct *tsk)             { }
1795 static inline void perf_event_text_poke(const void *addr,
1796                                         const void *old_bytes,
1797                                         size_t old_len,
1798                                         const void *new_bytes,
1799                                         size_t new_len)                 { }
1800 static inline void perf_event_init(void)                                { }
1801 static inline int  perf_swevent_get_recursion_context(void)             { return -1; }
1802 static inline void perf_swevent_put_recursion_context(int rctx)         { }
1803 static inline u64 perf_swevent_set_period(struct perf_event *event)     { return 0; }
1804 static inline void perf_event_enable(struct perf_event *event)          { }
1805 static inline void perf_event_disable(struct perf_event *event)         { }
1806 static inline int __perf_event_disable(void *info)                      { return -1; }
1807 static inline void perf_event_task_tick(void)                           { }
1808 static inline int perf_event_release_kernel(struct perf_event *event)   { return 0; }
1809 static inline int perf_event_period(struct perf_event *event, u64 value)
1810 {
1811         return -EINVAL;
1812 }
1813 static inline u64 perf_event_pause(struct perf_event *event, bool reset)
1814 {
1815         return 0;
1816 }
1817 #endif
1818
1819 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
1820 extern void perf_restore_debug_store(void);
1821 #else
1822 static inline void perf_restore_debug_store(void)                       { }
1823 #endif
1824
1825 #define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
1826
1827 struct perf_pmu_events_attr {
1828         struct device_attribute attr;
1829         u64 id;
1830         const char *event_str;
1831 };
1832
1833 struct perf_pmu_events_ht_attr {
1834         struct device_attribute                 attr;
1835         u64                                     id;
1836         const char                              *event_str_ht;
1837         const char                              *event_str_noht;
1838 };
1839
1840 struct perf_pmu_events_hybrid_attr {
1841         struct device_attribute                 attr;
1842         u64                                     id;
1843         const char                              *event_str;
1844         u64                                     pmu_type;
1845 };
1846
1847 struct perf_pmu_format_hybrid_attr {
1848         struct device_attribute                 attr;
1849         u64                                     pmu_type;
1850 };
1851
1852 ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
1853                               char *page);
1854
1855 #define PMU_EVENT_ATTR(_name, _var, _id, _show)                         \
1856 static struct perf_pmu_events_attr _var = {                             \
1857         .attr = __ATTR(_name, 0444, _show, NULL),                       \
1858         .id   =  _id,                                                   \
1859 };
1860
1861 #define PMU_EVENT_ATTR_STRING(_name, _var, _str)                            \
1862 static struct perf_pmu_events_attr _var = {                                 \
1863         .attr           = __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
1864         .id             = 0,                                                \
1865         .event_str      = _str,                                             \
1866 };
1867
1868 #define PMU_EVENT_ATTR_ID(_name, _show, _id)                            \
1869         (&((struct perf_pmu_events_attr[]) {                            \
1870                 { .attr = __ATTR(_name, 0444, _show, NULL),             \
1871                   .id = _id, }                                          \
1872         })[0].attr.attr)
1873
1874 #define PMU_FORMAT_ATTR_SHOW(_name, _format)                            \
1875 static ssize_t                                                          \
1876 _name##_show(struct device *dev,                                        \
1877                                struct device_attribute *attr,           \
1878                                char *page)                              \
1879 {                                                                       \
1880         BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);                     \
1881         return sprintf(page, _format "\n");                             \
1882 }                                                                       \
1883
1884 #define PMU_FORMAT_ATTR(_name, _format)                                 \
1885         PMU_FORMAT_ATTR_SHOW(_name, _format)                            \
1886                                                                         \
1887 static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
1888
1889 /* Performance counter hotplug functions */
1890 #ifdef CONFIG_PERF_EVENTS
1891 int perf_event_init_cpu(unsigned int cpu);
1892 int perf_event_exit_cpu(unsigned int cpu);
1893 #else
1894 #define perf_event_init_cpu     NULL
1895 #define perf_event_exit_cpu     NULL
1896 #endif
1897
1898 extern void arch_perf_update_userpage(struct perf_event *event,
1899                                       struct perf_event_mmap_page *userpg,
1900                                       u64 now);
1901
1902 /*
1903  * Snapshot branch stack on software events.
1904  *
1905  * Branch stack can be very useful in understanding software events. For
1906  * example, when a long function, e.g. sys_perf_event_open, returns an
1907  * errno, it is not obvious why the function failed. Branch stack could
1908  * provide very helpful information in this type of scenarios.
1909  *
1910  * On software event, it is necessary to stop the hardware branch recorder
1911  * fast. Otherwise, the hardware register/buffer will be flushed with
1912  * entries of the triggering event. Therefore, static call is used to
1913  * stop the hardware recorder.
1914  */
1915
1916 /*
1917  * cnt is the number of entries allocated for entries.
1918  * Return number of entries copied to .
1919  */
1920 typedef int (perf_snapshot_branch_stack_t)(struct perf_branch_entry *entries,
1921                                            unsigned int cnt);
1922 DECLARE_STATIC_CALL(perf_snapshot_branch_stack, perf_snapshot_branch_stack_t);
1923
1924 #ifndef PERF_NEEDS_LOPWR_CB
1925 static inline void perf_lopwr_cb(bool mode)
1926 {
1927 }
1928 #endif
1929
1930 #endif /* _LINUX_PERF_EVENT_H */