SAFE public projects git trees. - safe/jmp/linux-2.6/blob - include/linux/perf_counter.h

   1 /*
   2  *  Performance counters:
   3  *
   4  *   Copyright(C) 2008, Thomas Gleixner <tglx@linutronix.de>
   5  *   Copyright(C) 2008, Red Hat, Inc., Ingo Molnar
   6  *
   7  *  Data type definitions, declarations, prototypes.
   8  *
   9  *  Started by: Thomas Gleixner and Ingo Molnar
  10  *
  11  *  For licencing details see kernel-base/COPYING
  12  */
  13 #ifndef _LINUX_PERF_COUNTER_H
  14 #define _LINUX_PERF_COUNTER_H
  15
  16 #include <linux/types.h>
  17 #include <linux/ioctl.h>
  18 #include <asm/byteorder.h>
  19
  20 /*
  21  * User-space ABI bits:
  22  */
  23
  24 /*
  25  * attr.type
  26  */
  27 enum perf_type_id {
  28         PERF_TYPE_HARDWARE              = 0,
  29         PERF_TYPE_SOFTWARE              = 1,
  30         PERF_TYPE_TRACEPOINT            = 2,
  31         PERF_TYPE_HW_CACHE              = 3,
  32         PERF_TYPE_RAW                   = 4,
  33
  34         PERF_TYPE_MAX,                  /* non ABI */
  35 };
  36
  37 /*
  38  * Generalized performance counter event types, used by the attr.event_id
  39  * parameter of the sys_perf_counter_open() syscall:
  40  */
  41 enum perf_hw_id {
  42         /*
  43          * Common hardware events, generalized by the kernel:
  44          */
  45         PERF_COUNT_HW_CPU_CYCLES                = 0,
  46         PERF_COUNT_HW_INSTRUCTIONS              = 1,
  47         PERF_COUNT_HW_CACHE_REFERENCES          = 2,
  48         PERF_COUNT_HW_CACHE_MISSES              = 3,
  49         PERF_COUNT_HW_BRANCH_INSTRUCTIONS       = 4,
  50         PERF_COUNT_HW_BRANCH_MISSES             = 5,
  51         PERF_COUNT_HW_BUS_CYCLES                = 6,
  52
  53         PERF_COUNT_HW_MAX,              /* non ABI */
  54 };
  55
  56 /*
  57  * Generalized hardware cache counters:
  58  *
  59  *       { L1-D, L1-I, LLC, ITLB, DTLB, BPU } x
  60  *       { read, write, prefetch } x
  61  *       { accesses, misses }
  62  */
  63 enum perf_hw_cache_id {
  64         PERF_COUNT_HW_CACHE_L1D         = 0,
  65         PERF_COUNT_HW_CACHE_L1I         = 1,
  66         PERF_COUNT_HW_CACHE_LL          = 2,
  67         PERF_COUNT_HW_CACHE_DTLB        = 3,
  68         PERF_COUNT_HW_CACHE_ITLB        = 4,
  69         PERF_COUNT_HW_CACHE_BPU         = 5,
  70
  71         PERF_COUNT_HW_CACHE_MAX,        /* non ABI */
  72 };
  73
  74 enum perf_hw_cache_op_id {
  75         PERF_COUNT_HW_CACHE_OP_READ     = 0,
  76         PERF_COUNT_HW_CACHE_OP_WRITE    = 1,
  77         PERF_COUNT_HW_CACHE_OP_PREFETCH = 2,
  78
  79         PERF_COUNT_HW_CACHE_OP_MAX,     /* non ABI */
  80 };
  81
  82 enum perf_hw_cache_op_result_id {
  83         PERF_COUNT_HW_CACHE_RESULT_ACCESS       = 0,
  84         PERF_COUNT_HW_CACHE_RESULT_MISS         = 1,
  85
  86         PERF_COUNT_HW_CACHE_RESULT_MAX,         /* non ABI */
  87 };
  88
  89 /*
  90  * Special "software" counters provided by the kernel, even if the hardware
  91  * does not support performance counters. These counters measure various
  92  * physical and sw events of the kernel (and allow the profiling of them as
  93  * well):
  94  */
  95 enum perf_sw_ids {
  96         PERF_COUNT_SW_CPU_CLOCK         = 0,
  97         PERF_COUNT_SW_TASK_CLOCK        = 1,
  98         PERF_COUNT_SW_PAGE_FAULTS       = 2,
  99         PERF_COUNT_SW_CONTEXT_SWITCHES  = 3,
 100         PERF_COUNT_SW_CPU_MIGRATIONS    = 4,
 101         PERF_COUNT_SW_PAGE_FAULTS_MIN   = 5,
 102         PERF_COUNT_SW_PAGE_FAULTS_MAJ   = 6,
 103
 104         PERF_COUNT_SW_MAX,              /* non ABI */
 105 };
 106
 107 /*
 108  * Bits that can be set in attr.sample_type to request information
 109  * in the overflow packets.
 110  */
 111 enum perf_counter_sample_format {
 112         PERF_SAMPLE_IP                  = 1U << 0,
 113         PERF_SAMPLE_TID                 = 1U << 1,
 114         PERF_SAMPLE_TIME                = 1U << 2,
 115         PERF_SAMPLE_ADDR                = 1U << 3,
 116         PERF_SAMPLE_GROUP               = 1U << 4,
 117         PERF_SAMPLE_CALLCHAIN           = 1U << 5,
 118         PERF_SAMPLE_ID                  = 1U << 6,
 119         PERF_SAMPLE_CPU                 = 1U << 7,
 120         PERF_SAMPLE_PERIOD              = 1U << 8,
 121 };
 122
 123 /*
 124  * Bits that can be set in attr.read_format to request that
 125  * reads on the counter should return the indicated quantities,
 126  * in increasing order of bit value, after the counter value.
 127  */
 128 enum perf_counter_read_format {
 129         PERF_FORMAT_TOTAL_TIME_ENABLED  =  1U << 0,
 130         PERF_FORMAT_TOTAL_TIME_RUNNING  =  1U << 1,
 131         PERF_FORMAT_ID                  =  1U << 2,
 132 };
 133
 134 /*
 135  * Hardware event to monitor via a performance monitoring counter:
 136  */
 137 struct perf_counter_attr {
 138         /*
 139          * Major type: hardware/software/tracepoint/etc.
 140          */
 141         __u32                   type;
 142         __u32                   __reserved_1;
 143
 144         /*
 145          * Type specific configuration information.
 146          */
 147         __u64                   config;
 148
 149         union {
 150                 __u64           sample_period;
 151                 __u64           sample_freq;
 152         };
 153
 154         __u64                   sample_type;
 155         __u64                   read_format;
 156
 157         __u64                   disabled       :  1, /* off by default        */
 158                                 inherit        :  1, /* children inherit it   */
 159                                 pinned         :  1, /* must always be on PMU */
 160                                 exclusive      :  1, /* only group on PMU     */
 161                                 exclude_user   :  1, /* don't count user      */
 162                                 exclude_kernel :  1, /* ditto kernel          */
 163                                 exclude_hv     :  1, /* ditto hypervisor      */
 164                                 exclude_idle   :  1, /* don't count when idle */
 165                                 mmap           :  1, /* include mmap data     */
 166                                 comm           :  1, /* include comm data     */
 167                                 freq           :  1, /* use freq, not period  */
 168
 169                                 __reserved_2   : 53;
 170
 171         __u32                   wakeup_events;  /* wakeup every n events */
 172         __u32                   __reserved_3;
 173
 174         __u64                   __reserved_4;
 175 };
 176
 177 /*
 178  * Ioctls that can be done on a perf counter fd:
 179  */
 180 #define PERF_COUNTER_IOC_ENABLE         _IO ('$', 0)
 181 #define PERF_COUNTER_IOC_DISABLE        _IO ('$', 1)
 182 #define PERF_COUNTER_IOC_REFRESH        _IO ('$', 2)
 183 #define PERF_COUNTER_IOC_RESET          _IO ('$', 3)
 184 #define PERF_COUNTER_IOC_PERIOD         _IOW('$', 4, u64)
 185
 186 enum perf_counter_ioc_flags {
 187         PERF_IOC_FLAG_GROUP             = 1U << 0,
 188 };
 189
 190 /*
 191  * Structure of the page that can be mapped via mmap
 192  */
 193 struct perf_counter_mmap_page {
 194         __u32   version;                /* version number of this structure */
 195         __u32   compat_version;         /* lowest version this is compat with */
 196
 197         /*
 198          * Bits needed to read the hw counters in user-space.
 199          *
 200          *   u32 seq;
 201          *   s64 count;
 202          *
 203          *   do {
 204          *     seq = pc->lock;
 205          *
 206          *     barrier()
 207          *     if (pc->index) {
 208          *       count = pmc_read(pc->index - 1);
 209          *       count += pc->offset;
 210          *     } else
 211          *       goto regular_read;
 212          *
 213          *     barrier();
 214          *   } while (pc->lock != seq);
 215          *
 216          * NOTE: for obvious reason this only works on self-monitoring
 217          *       processes.
 218          */
 219         __u32   lock;                   /* seqlock for synchronization */
 220         __u32   index;                  /* hardware counter identifier */
 221         __s64   offset;                 /* add to hardware counter value */
 222
 223         /*
 224          * Control data for the mmap() data buffer.
 225          *
 226          * User-space reading this value should issue an rmb(), on SMP capable
 227          * platforms, after reading this value -- see perf_counter_wakeup().
 228          */
 229         __u64   data_head;              /* head in the data section */
 230 };
 231
 232 #define PERF_EVENT_MISC_CPUMODE_MASK    (3 << 0)
 233 #define PERF_EVENT_MISC_CPUMODE_UNKNOWN (0 << 0)
 234 #define PERF_EVENT_MISC_KERNEL          (1 << 0)
 235 #define PERF_EVENT_MISC_USER            (2 << 0)
 236 #define PERF_EVENT_MISC_HYPERVISOR      (3 << 0)
 237 #define PERF_EVENT_MISC_OVERFLOW        (1 << 2)
 238
 239 struct perf_event_header {
 240         __u32   type;
 241         __u16   misc;
 242         __u16   size;
 243 };
 244
 245 enum perf_event_type {
 246
 247         /*
 248          * The MMAP events record the PROT_EXEC mappings so that we can
 249          * correlate userspace IPs to code. They have the following structure:
 250          *
 251          * struct {
 252          *      struct perf_event_header        header;
 253          *
 254          *      u32                             pid, tid;
 255          *      u64                             addr;
 256          *      u64                             len;
 257          *      u64                             pgoff;
 258          *      char                            filename[];
 259          * };
 260          */
 261         PERF_EVENT_MMAP                 = 1,
 262
 263         /*
 264          * struct {
 265          *      struct perf_event_header        header;
 266          *
 267          *      u32                             pid, tid;
 268          *      char                            comm[];
 269          * };
 270          */
 271         PERF_EVENT_COMM                 = 3,
 272
 273         /*
 274          * struct {
 275          *      struct perf_event_header        header;
 276          *      u64                             time;
 277          *      u64                             id;
 278          *      u64                             sample_period;
 279          * };
 280          */
 281         PERF_EVENT_PERIOD               = 4,
 282
 283         /*
 284          * struct {
 285          *      struct perf_event_header        header;
 286          *      u64                             time;
 287          * };
 288          */
 289         PERF_EVENT_THROTTLE             = 5,
 290         PERF_EVENT_UNTHROTTLE           = 6,
 291
 292         /*
 293          * struct {
 294          *      struct perf_event_header        header;
 295          *      u32                             pid, ppid;
 296          * };
 297          */
 298         PERF_EVENT_FORK                 = 7,
 299
 300         /*
 301          * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field
 302          * will be PERF_RECORD_*
 303          *
 304          * struct {
 305          *      struct perf_event_header        header;
 306          *
 307          *      { u64                   ip;       } && PERF_RECORD_IP
 308          *      { u32                   pid, tid; } && PERF_RECORD_TID
 309          *      { u64                   time;     } && PERF_RECORD_TIME
 310          *      { u64                   addr;     } && PERF_RECORD_ADDR
 311          *      { u64                   config;   } && PERF_RECORD_CONFIG
 312          *      { u32                   cpu, res; } && PERF_RECORD_CPU
 313          *
 314          *      { u64                   nr;
 315          *        { u64 id, val; }      cnt[nr];  } && PERF_RECORD_GROUP
 316          *
 317          *      { u16                   nr,
 318          *                              hv,
 319          *                              kernel,
 320          *                              user;
 321          *        u64                   ips[nr];  } && PERF_RECORD_CALLCHAIN
 322          * };
 323          */
 324 };
 325
 326 #ifdef __KERNEL__
 327 /*
 328  * Kernel-internal data types and definitions:
 329  */
 330
 331 #ifdef CONFIG_PERF_COUNTERS
 332 # include <asm/perf_counter.h>
 333 #endif
 334
 335 #include <linux/list.h>
 336 #include <linux/mutex.h>
 337 #include <linux/rculist.h>
 338 #include <linux/rcupdate.h>
 339 #include <linux/spinlock.h>
 340 #include <linux/hrtimer.h>
 341 #include <linux/fs.h>
 342 #include <linux/pid_namespace.h>
 343 #include <asm/atomic.h>
 344
 345 struct task_struct;
 346
 347 /**
 348  * struct hw_perf_counter - performance counter hardware details:
 349  */
 350 struct hw_perf_counter {
 351 #ifdef CONFIG_PERF_COUNTERS
 352         union {
 353                 struct { /* hardware */
 354                         u64                             config;
 355                         unsigned long                   config_base;
 356                         unsigned long                   counter_base;
 357                         int                             idx;
 358                 };
 359                 union { /* software */
 360                         atomic64_t                      count;
 361                         struct hrtimer                  hrtimer;
 362                 };
 363         };
 364         atomic64_t                      prev_count;
 365         u64                             sample_period;
 366         u64                             last_period;
 367         atomic64_t                      period_left;
 368         u64                             interrupts;
 369
 370         u64                             freq_count;
 371         u64                             freq_interrupts;
 372         u64                             freq_stamp;
 373 #endif
 374 };
 375
 376 struct perf_counter;
 377
 378 /**
 379  * struct pmu - generic performance monitoring unit
 380  */
 381 struct pmu {
 382         int (*enable)                   (struct perf_counter *counter);
 383         void (*disable)                 (struct perf_counter *counter);
 384         void (*read)                    (struct perf_counter *counter);
 385         void (*unthrottle)              (struct perf_counter *counter);
 386 };
 387
 388 /**
 389  * enum perf_counter_active_state - the states of a counter
 390  */
 391 enum perf_counter_active_state {
 392         PERF_COUNTER_STATE_ERROR        = -2,
 393         PERF_COUNTER_STATE_OFF          = -1,
 394         PERF_COUNTER_STATE_INACTIVE     =  0,
 395         PERF_COUNTER_STATE_ACTIVE       =  1,
 396 };
 397
 398 struct file;
 399
 400 struct perf_mmap_data {
 401         struct rcu_head                 rcu_head;
 402         int                             nr_pages;       /* nr of data pages  */
 403         int                             nr_locked;      /* nr pages mlocked  */
 404
 405         atomic_t                        poll;           /* POLL_ for wakeups */
 406         atomic_t                        events;         /* event limit       */
 407
 408         atomic_long_t                   head;           /* write position    */
 409         atomic_long_t                   done_head;      /* completed head    */
 410
 411         atomic_t                        lock;           /* concurrent writes */
 412
 413         atomic_t                        wakeup;         /* needs a wakeup    */
 414
 415         struct perf_counter_mmap_page   *user_page;
 416         void                            *data_pages[0];
 417 };
 418
 419 struct perf_pending_entry {
 420         struct perf_pending_entry *next;
 421         void (*func)(struct perf_pending_entry *);
 422 };
 423
 424 /**
 425  * struct perf_counter - performance counter kernel representation:
 426  */
 427 struct perf_counter {
 428 #ifdef CONFIG_PERF_COUNTERS
 429         struct list_head                list_entry;
 430         struct list_head                event_entry;
 431         struct list_head                sibling_list;
 432         int                             nr_siblings;
 433         struct perf_counter             *group_leader;
 434         const struct pmu                *pmu;
 435
 436         enum perf_counter_active_state  state;
 437         atomic64_t                      count;
 438
 439         /*
 440          * These are the total time in nanoseconds that the counter
 441          * has been enabled (i.e. eligible to run, and the task has
 442          * been scheduled in, if this is a per-task counter)
 443          * and running (scheduled onto the CPU), respectively.
 444          *
 445          * They are computed from tstamp_enabled, tstamp_running and
 446          * tstamp_stopped when the counter is in INACTIVE or ACTIVE state.
 447          */
 448         u64                             total_time_enabled;
 449         u64                             total_time_running;
 450
 451         /*
 452          * These are timestamps used for computing total_time_enabled
 453          * and total_time_running when the counter is in INACTIVE or
 454          * ACTIVE state, measured in nanoseconds from an arbitrary point
 455          * in time.
 456          * tstamp_enabled: the notional time when the counter was enabled
 457          * tstamp_running: the notional time when the counter was scheduled on
 458          * tstamp_stopped: in INACTIVE state, the notional time when the
 459          *      counter was scheduled off.
 460          */
 461         u64                             tstamp_enabled;
 462         u64                             tstamp_running;
 463         u64                             tstamp_stopped;
 464
 465         struct perf_counter_attr        attr;
 466         struct hw_perf_counter          hw;
 467
 468         struct perf_counter_context     *ctx;
 469         struct file                     *filp;
 470
 471         /*
 472          * These accumulate total time (in nanoseconds) that children
 473          * counters have been enabled and running, respectively.
 474          */
 475         atomic64_t                      child_total_time_enabled;
 476         atomic64_t                      child_total_time_running;
 477
 478         /*
 479          * Protect attach/detach and child_list:
 480          */
 481         struct mutex                    child_mutex;
 482         struct list_head                child_list;
 483         struct perf_counter             *parent;
 484
 485         int                             oncpu;
 486         int                             cpu;
 487
 488         struct list_head                owner_entry;
 489         struct task_struct              *owner;
 490
 491         /* mmap bits */
 492         struct mutex                    mmap_mutex;
 493         atomic_t                        mmap_count;
 494         struct perf_mmap_data           *data;
 495
 496         /* poll related */
 497         wait_queue_head_t               waitq;
 498         struct fasync_struct            *fasync;
 499
 500         /* delayed work for NMIs and such */
 501         int                             pending_wakeup;
 502         int                             pending_kill;
 503         int                             pending_disable;
 504         struct perf_pending_entry       pending;
 505
 506         atomic_t                        event_limit;
 507
 508         void (*destroy)(struct perf_counter *);
 509         struct rcu_head                 rcu_head;
 510
 511         struct pid_namespace            *ns;
 512         u64                             id;
 513 #endif
 514 };
 515
 516 /**
 517  * struct perf_counter_context - counter context structure
 518  *
 519  * Used as a container for task counters and CPU counters as well:
 520  */
 521 struct perf_counter_context {
 522         /*
 523          * Protect the states of the counters in the list,
 524          * nr_active, and the list:
 525          */
 526         spinlock_t              lock;
 527         /*
 528          * Protect the list of counters.  Locking either mutex or lock
 529          * is sufficient to ensure the list doesn't change; to change
 530          * the list you need to lock both the mutex and the spinlock.
 531          */
 532         struct mutex            mutex;
 533
 534         struct list_head        counter_list;
 535         struct list_head        event_list;
 536         int                     nr_counters;
 537         int                     nr_active;
 538         int                     is_active;
 539         atomic_t                refcount;
 540         struct task_struct      *task;
 541
 542         /*
 543          * Context clock, runs when context enabled.
 544          */
 545         u64                     time;
 546         u64                     timestamp;
 547
 548         /*
 549          * These fields let us detect when two contexts have both
 550          * been cloned (inherited) from a common ancestor.
 551          */
 552         struct perf_counter_context *parent_ctx;
 553         u64                     parent_gen;
 554         u64                     generation;
 555         int                     pin_count;
 556         struct rcu_head         rcu_head;
 557 };
 558
 559 /**
 560  * struct perf_counter_cpu_context - per cpu counter context structure
 561  */
 562 struct perf_cpu_context {
 563         struct perf_counter_context     ctx;
 564         struct perf_counter_context     *task_ctx;
 565         int                             active_oncpu;
 566         int                             max_pertask;
 567         int                             exclusive;
 568
 569         /*
 570          * Recursion avoidance:
 571          *
 572          * task, softirq, irq, nmi context
 573          */
 574         int                             recursion[4];
 575 };
 576
 577 #ifdef CONFIG_PERF_COUNTERS
 578
 579 /*
 580  * Set by architecture code:
 581  */
 582 extern int perf_max_counters;
 583
 584 extern const struct pmu *hw_perf_counter_init(struct perf_counter *counter);
 585
 586 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
 587 extern void perf_counter_task_sched_out(struct task_struct *task,
 588                                         struct task_struct *next, int cpu);
 589 extern void perf_counter_task_tick(struct task_struct *task, int cpu);
 590 extern int perf_counter_init_task(struct task_struct *child);
 591 extern void perf_counter_exit_task(struct task_struct *child);
 592 extern void perf_counter_free_task(struct task_struct *task);
 593 extern void perf_counter_do_pending(void);
 594 extern void perf_counter_print_debug(void);
 595 extern void __perf_disable(void);
 596 extern bool __perf_enable(void);
 597 extern void perf_disable(void);
 598 extern void perf_enable(void);
 599 extern int perf_counter_task_disable(void);
 600 extern int perf_counter_task_enable(void);
 601 extern int hw_perf_group_sched_in(struct perf_counter *group_leader,
 602                struct perf_cpu_context *cpuctx,
 603                struct perf_counter_context *ctx, int cpu);
 604 extern void perf_counter_update_userpage(struct perf_counter *counter);
 605
 606 struct perf_sample_data {
 607         struct pt_regs          *regs;
 608         u64                     addr;
 609         u64                     period;
 610 };
 611
 612 extern int perf_counter_overflow(struct perf_counter *counter, int nmi,
 613                                  struct perf_sample_data *data);
 614
 615 /*
 616  * Return 1 for a software counter, 0 for a hardware counter
 617  */
 618 static inline int is_software_counter(struct perf_counter *counter)
 619 {
 620         return (counter->attr.type != PERF_TYPE_RAW) &&
 621                 (counter->attr.type != PERF_TYPE_HARDWARE);
 622 }
 623
 624 extern void perf_swcounter_event(u32, u64, int, struct pt_regs *, u64);
 625
 626 extern void __perf_counter_mmap(struct vm_area_struct *vma);
 627
 628 static inline void perf_counter_mmap(struct vm_area_struct *vma)
 629 {
 630         if (vma->vm_flags & VM_EXEC)
 631                 __perf_counter_mmap(vma);
 632 }
 633
 634 extern void perf_counter_comm(struct task_struct *tsk);
 635 extern void perf_counter_fork(struct task_struct *tsk);
 636
 637 extern void perf_counter_task_migration(struct task_struct *task, int cpu);
 638
 639 #define MAX_STACK_DEPTH         255
 640
 641 struct perf_callchain_entry {
 642         u16     nr, hv, kernel, user;
 643         u64     ip[MAX_STACK_DEPTH];
 644 };
 645
 646 extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);
 647
 648 extern int sysctl_perf_counter_paranoid;
 649 extern int sysctl_perf_counter_mlock;
 650 extern int sysctl_perf_counter_sample_rate;
 651
 652 extern void perf_counter_init(void);
 653
 654 #ifndef perf_misc_flags
 655 #define perf_misc_flags(regs)   (user_mode(regs) ? PERF_EVENT_MISC_USER : \
 656                                  PERF_EVENT_MISC_KERNEL)
 657 #define perf_instruction_pointer(regs)  instruction_pointer(regs)
 658 #endif
 659
 660 #else
 661 static inline void
 662 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
 663 static inline void
 664 perf_counter_task_sched_out(struct task_struct *task,
 665                             struct task_struct *next, int cpu)          { }
 666 static inline void
 667 perf_counter_task_tick(struct task_struct *task, int cpu)               { }
 668 static inline int perf_counter_init_task(struct task_struct *child)     { return 0; }
 669 static inline void perf_counter_exit_task(struct task_struct *child)    { }
 670 static inline void perf_counter_free_task(struct task_struct *task)     { }
 671 static inline void perf_counter_do_pending(void)                        { }
 672 static inline void perf_counter_print_debug(void)                       { }
 673 static inline void perf_disable(void)                                   { }
 674 static inline void perf_enable(void)                                    { }
 675 static inline int perf_counter_task_disable(void)       { return -EINVAL; }
 676 static inline int perf_counter_task_enable(void)        { return -EINVAL; }
 677
 678 static inline void
 679 perf_swcounter_event(u32 event, u64 nr, int nmi,
 680                      struct pt_regs *regs, u64 addr)                    { }
 681
 682 static inline void perf_counter_mmap(struct vm_area_struct *vma)        { }
 683 static inline void perf_counter_comm(struct task_struct *tsk)           { }
 684 static inline void perf_counter_fork(struct task_struct *tsk)           { }
 685 static inline void perf_counter_init(void)                              { }
 686 static inline void perf_counter_task_migration(struct task_struct *task,
 687                                                int cpu)                 { }
 688 #endif
 689
 690 #endif /* __KERNEL__ */
 691 #endif /* _LINUX_PERF_COUNTER_H */