include/linux/ftrace_event.h

   1
   2 #ifndef _LINUX_FTRACE_EVENT_H
   3 #define _LINUX_FTRACE_EVENT_H
   4
   5 #include <linux/ring_buffer.h>
   6 #include <linux/trace_seq.h>
   7 #include <linux/percpu.h>
   8 #include <linux/hardirq.h>
   9 #include <linux/perf_event.h>
  10
  11 struct trace_array;
  12 struct trace_buffer;
  13 struct tracer;
  14 struct dentry;
  15
  16 struct trace_print_flags {
  17         unsigned long           mask;
  18         const char              *name;
  19 };
  20
  21 struct trace_print_flags_u64 {
  22         unsigned long long      mask;
  23         const char              *name;
  24 };
  25
  26 const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  27                                    unsigned long flags,
  28                                    const struct trace_print_flags *flag_array);
  29
  30 const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  31                                      const struct trace_print_flags *symbol_array);
  32
  33 #if BITS_PER_LONG == 32
  34 const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
  35                                          unsigned long long val,
  36                                          const struct trace_print_flags_u64
  37                                                                  *symbol_array);
  38 #endif
  39
  40 const char *ftrace_print_hex_seq(struct trace_seq *p,
  41                                  const unsigned char *buf, int len);
  42
  43 struct trace_iterator;
  44 struct trace_event;
  45
  46 int ftrace_raw_output_prep(struct trace_iterator *iter,
  47                            struct trace_event *event);
  48
  49 /*
  50  * The trace entry - the most basic unit of tracing. This is what
  51  * is printed in the end as a single line in the trace output, such as:
  52  *
  53  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  54  */
  55 struct trace_entry {
  56         unsigned short          type;
  57         unsigned char           flags;
  58         unsigned char           preempt_count;
  59         int                     pid;
  60 };
  61
  62 #define FTRACE_MAX_EVENT                                                \
  63         ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
  64
  65 /*
  66  * Trace iterator - used by printout routines who present trace
  67  * results to users and which routines might sleep, etc:
  68  */
  69 struct trace_iterator {
  70         struct trace_array      *tr;
  71         struct tracer           *trace;
  72         struct trace_buffer     *trace_buffer;
  73         void                    *private;
  74         int                     cpu_file;
  75         struct mutex            mutex;
  76         struct ring_buffer_iter **buffer_iter;
  77         unsigned long           iter_flags;
  78
  79         /* trace_seq for __print_flags() and __print_symbolic() etc. */
  80         struct trace_seq        tmp_seq;
  81
  82         cpumask_var_t           started;
  83
  84         /* it's true when current open file is snapshot */
  85         bool                    snapshot;
  86
  87         /* The below is zeroed out in pipe_read */
  88         struct trace_seq        seq;
  89         struct trace_entry      *ent;
  90         unsigned long           lost_events;
  91         int                     leftover;
  92         int                     ent_size;
  93         int                     cpu;
  94         u64                     ts;
  95
  96         loff_t                  pos;
  97         long                    idx;
  98
  99         /* All new field here will be zeroed out in pipe_read */
 100 };
 101
 102 enum trace_iter_flags {
 103         TRACE_FILE_LAT_FMT      = 1,
 104         TRACE_FILE_ANNOTATE     = 2,
 105         TRACE_FILE_TIME_IN_NS   = 4,
 106 };
 107
 108
 109 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
 110                                       int flags, struct trace_event *event);
 111
 112 struct trace_event_functions {
 113         trace_print_func        trace;
 114         trace_print_func        raw;
 115         trace_print_func        hex;
 116         trace_print_func        binary;
 117 };
 118
 119 struct trace_event {
 120         struct hlist_node               node;
 121         struct list_head                list;
 122         int                             type;
 123         struct trace_event_functions    *funcs;
 124 };
 125
 126 extern int register_ftrace_event(struct trace_event *event);
 127 extern int unregister_ftrace_event(struct trace_event *event);
 128
 129 /* Return values for print_line callback */
 130 enum print_line_t {
 131         TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
 132         TRACE_TYPE_HANDLED      = 1,
 133         TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
 134         TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
 135 };
 136
 137 void tracing_generic_entry_update(struct trace_entry *entry,
 138                                   unsigned long flags,
 139                                   int pc);
 140 struct ftrace_event_file;
 141
 142 struct ring_buffer_event *
 143 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
 144                                 struct ftrace_event_file *ftrace_file,
 145                                 int type, unsigned long len,
 146                                 unsigned long flags, int pc);
 147 struct ring_buffer_event *
 148 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 149                                   int type, unsigned long len,
 150                                   unsigned long flags, int pc);
 151 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 152                                         struct ring_buffer_event *event,
 153                                         unsigned long flags, int pc);
 154 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 155                                 struct ring_buffer_event *event,
 156                                 unsigned long flags, int pc);
 157 void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
 158                                      struct ring_buffer_event *event,
 159                                      unsigned long flags, int pc,
 160                                      struct pt_regs *regs);
 161 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 162                                          struct ring_buffer_event *event);
 163
 164 void tracing_record_cmdline(struct task_struct *tsk);
 165
 166 struct event_filter;
 167
 168 enum trace_reg {
 169         TRACE_REG_REGISTER,
 170         TRACE_REG_UNREGISTER,
 171 #ifdef CONFIG_PERF_EVENTS
 172         TRACE_REG_PERF_REGISTER,
 173         TRACE_REG_PERF_UNREGISTER,
 174         TRACE_REG_PERF_OPEN,
 175         TRACE_REG_PERF_CLOSE,
 176         TRACE_REG_PERF_ADD,
 177         TRACE_REG_PERF_DEL,
 178 #endif
 179 };
 180
 181 struct ftrace_event_call;
 182
 183 struct ftrace_event_class {
 184         char                    *system;
 185         void                    *probe;
 186 #ifdef CONFIG_PERF_EVENTS
 187         void                    *perf_probe;
 188 #endif
 189         int                     (*reg)(struct ftrace_event_call *event,
 190                                        enum trace_reg type, void *data);
 191         int                     (*define_fields)(struct ftrace_event_call *);
 192         struct list_head        *(*get_fields)(struct ftrace_event_call *);
 193         struct list_head        fields;
 194         int                     (*raw_init)(struct ftrace_event_call *);
 195 };
 196
 197 extern int ftrace_event_reg(struct ftrace_event_call *event,
 198                             enum trace_reg type, void *data);
 199
 200 enum {
 201         TRACE_EVENT_FL_FILTERED_BIT,
 202         TRACE_EVENT_FL_CAP_ANY_BIT,
 203         TRACE_EVENT_FL_NO_SET_FILTER_BIT,
 204         TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
 205         TRACE_EVENT_FL_WAS_ENABLED_BIT,
 206         TRACE_EVENT_FL_USE_CALL_FILTER_BIT,
 207 };
 208
 209 /*
 210  * Event flags:
 211  *  FILTERED      - The event has a filter attached
 212  *  CAP_ANY       - Any user can enable for perf
 213  *  NO_SET_FILTER - Set when filter has error and is to be ignored
 214  *  IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
 215  *  WAS_ENABLED   - Set and stays set when an event was ever enabled
 216  *                    (used for module unloading, if a module event is enabled,
 217  *                     it is best to clear the buffers that used it).
 218  *  USE_CALL_FILTER - For ftrace internal events, don't use file filter
 219  */
 220 enum {
 221         TRACE_EVENT_FL_FILTERED         = (1 << TRACE_EVENT_FL_FILTERED_BIT),
 222         TRACE_EVENT_FL_CAP_ANY          = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
 223         TRACE_EVENT_FL_NO_SET_FILTER    = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
 224         TRACE_EVENT_FL_IGNORE_ENABLE    = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
 225         TRACE_EVENT_FL_WAS_ENABLED      = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
 226         TRACE_EVENT_FL_USE_CALL_FILTER  = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT),
 227 };
 228
 229 struct ftrace_event_call {
 230         struct list_head        list;
 231         struct ftrace_event_class *class;
 232         char                    *name;
 233         struct trace_event      event;
 234         const char              *print_fmt;
 235         struct event_filter     *filter;
 236         struct list_head        *files;
 237         void                    *mod;
 238         void                    *data;
 239         /*
 240          *   bit 0:             filter_active
 241          *   bit 1:             allow trace by non root (cap any)
 242          *   bit 2:             failed to apply filter
 243          *   bit 3:             ftrace internal event (do not enable)
 244          *   bit 4:             Event was enabled by module
 245          *   bit 5:             use call filter rather than file filter
 246          */
 247         int                     flags; /* static flags of different events */
 248
 249 #ifdef CONFIG_PERF_EVENTS
 250         int                             perf_refcount;
 251         struct hlist_head __percpu      *perf_events;
 252
 253         int     (*perf_perm)(struct ftrace_event_call *,
 254                              struct perf_event *);
 255 #endif
 256 };
 257
 258 struct trace_array;
 259 struct ftrace_subsystem_dir;
 260
 261 enum {
 262         FTRACE_EVENT_FL_ENABLED_BIT,
 263         FTRACE_EVENT_FL_RECORDED_CMD_BIT,
 264         FTRACE_EVENT_FL_FILTERED_BIT,
 265         FTRACE_EVENT_FL_NO_SET_FILTER_BIT,
 266         FTRACE_EVENT_FL_SOFT_MODE_BIT,
 267         FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
 268         FTRACE_EVENT_FL_TRIGGER_MODE_BIT,
 269         FTRACE_EVENT_FL_TRIGGER_COND_BIT,
 270 };
 271
 272 /*
 273  * Ftrace event file flags:
 274  *  ENABLED       - The event is enabled
 275  *  RECORDED_CMD  - The comms should be recorded at sched_switch
 276  *  FILTERED      - The event has a filter attached
 277  *  NO_SET_FILTER - Set when filter has error and is to be ignored
 278  *  SOFT_MODE     - The event is enabled/disabled by SOFT_DISABLED
 279  *  SOFT_DISABLED - When set, do not trace the event (even though its
 280  *                   tracepoint may be enabled)
 281  *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
 282  *  TRIGGER_COND  - When set, one or more triggers has an associated filter
 283  */
 284 enum {
 285         FTRACE_EVENT_FL_ENABLED         = (1 << FTRACE_EVENT_FL_ENABLED_BIT),
 286         FTRACE_EVENT_FL_RECORDED_CMD    = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT),
 287         FTRACE_EVENT_FL_FILTERED        = (1 << FTRACE_EVENT_FL_FILTERED_BIT),
 288         FTRACE_EVENT_FL_NO_SET_FILTER   = (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT),
 289         FTRACE_EVENT_FL_SOFT_MODE       = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT),
 290         FTRACE_EVENT_FL_SOFT_DISABLED   = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT),
 291         FTRACE_EVENT_FL_TRIGGER_MODE    = (1 << FTRACE_EVENT_FL_TRIGGER_MODE_BIT),
 292         FTRACE_EVENT_FL_TRIGGER_COND    = (1 << FTRACE_EVENT_FL_TRIGGER_COND_BIT),
 293 };
 294
 295 struct ftrace_event_file {
 296         struct list_head                list;
 297         struct ftrace_event_call        *event_call;
 298         struct event_filter             *filter;
 299         struct dentry                   *dir;
 300         struct trace_array              *tr;
 301         struct ftrace_subsystem_dir     *system;
 302         struct list_head                triggers;
 303
 304         /*
 305          * 32 bit flags:
 306          *   bit 0:             enabled
 307          *   bit 1:             enabled cmd record
 308          *   bit 2:             enable/disable with the soft disable bit
 309          *   bit 3:             soft disabled
 310          *   bit 4:             trigger enabled
 311          *
 312          * Note: The bits must be set atomically to prevent races
 313          * from other writers. Reads of flags do not need to be in
 314          * sync as they occur in critical sections. But the way flags
 315          * is currently used, these changes do not affect the code
 316          * except that when a change is made, it may have a slight
 317          * delay in propagating the changes to other CPUs due to
 318          * caching and such. Which is mostly OK ;-)
 319          */
 320         unsigned long           flags;
 321         atomic_t                sm_ref; /* soft-mode reference counter */
 322         atomic_t                tm_ref; /* trigger-mode reference counter */
 323 };
 324
 325 #define __TRACE_EVENT_FLAGS(name, value)                                \
 326         static int __init trace_init_flags_##name(void)                 \
 327         {                                                               \
 328                 event_##name.flags = value;                             \
 329                 return 0;                                               \
 330         }                                                               \
 331         early_initcall(trace_init_flags_##name);
 332
 333 #define __TRACE_EVENT_PERF_PERM(name, expr...)                          \
 334         static int perf_perm_##name(struct ftrace_event_call *tp_event, \
 335                                     struct perf_event *p_event)         \
 336         {                                                               \
 337                 return ({ expr; });                                     \
 338         }                                                               \
 339         static int __init trace_init_perf_perm_##name(void)             \
 340         {                                                               \
 341                 event_##name.perf_perm = &perf_perm_##name;             \
 342                 return 0;                                               \
 343         }                                                               \
 344         early_initcall(trace_init_perf_perm_##name);
 345
 346 #define PERF_MAX_TRACE_SIZE     2048
 347
 348 #define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 349
 350 enum event_trigger_type {
 351         ETT_NONE                = (0),
 352         ETT_TRACE_ONOFF         = (1 << 0),
 353         ETT_SNAPSHOT            = (1 << 1),
 354         ETT_STACKTRACE          = (1 << 2),
 355         ETT_EVENT_ENABLE        = (1 << 3),
 356 };
 357
 358 extern void destroy_preds(struct ftrace_event_file *file);
 359 extern void destroy_call_preds(struct ftrace_event_call *call);
 360 extern int filter_match_preds(struct event_filter *filter, void *rec);
 361
 362 extern int filter_check_discard(struct ftrace_event_file *file, void *rec,
 363                                 struct ring_buffer *buffer,
 364                                 struct ring_buffer_event *event);
 365 extern int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
 366                                      struct ring_buffer *buffer,
 367                                      struct ring_buffer_event *event);
 368 extern enum event_trigger_type event_triggers_call(struct ftrace_event_file *file,
 369                                                    void *rec);
 370 extern void event_triggers_post_call(struct ftrace_event_file *file,
 371                                      enum event_trigger_type tt);
 372
 373 /**
 374  * ftrace_trigger_soft_disabled - do triggers and test if soft disabled
 375  * @file: The file pointer of the event to test
 376  *
 377  * If any triggers without filters are attached to this event, they
 378  * will be called here. If the event is soft disabled and has no
 379  * triggers that require testing the fields, it will return true,
 380  * otherwise false.
 381  */
 382 static inline bool
 383 ftrace_trigger_soft_disabled(struct ftrace_event_file *file)
 384 {
 385         unsigned long eflags = file->flags;
 386
 387         if (!(eflags & FTRACE_EVENT_FL_TRIGGER_COND)) {
 388                 if (eflags & FTRACE_EVENT_FL_TRIGGER_MODE)
 389                         event_triggers_call(file, NULL);
 390                 if (eflags & FTRACE_EVENT_FL_SOFT_DISABLED)
 391                         return true;
 392         }
 393         return false;
 394 }
 395
 396 /*
 397  * Helper function for event_trigger_unlock_commit{_regs}().
 398  * If there are event triggers attached to this event that requires
 399  * filtering against its fields, then they wil be called as the
 400  * entry already holds the field information of the current event.
 401  *
 402  * It also checks if the event should be discarded or not.
 403  * It is to be discarded if the event is soft disabled and the
 404  * event was only recorded to process triggers, or if the event
 405  * filter is active and this event did not match the filters.
 406  *
 407  * Returns true if the event is discarded, false otherwise.
 408  */
 409 static inline bool
 410 __event_trigger_test_discard(struct ftrace_event_file *file,
 411                              struct ring_buffer *buffer,
 412                              struct ring_buffer_event *event,
 413                              void *entry,
 414                              enum event_trigger_type *tt)
 415 {
 416         unsigned long eflags = file->flags;
 417
 418         if (eflags & FTRACE_EVENT_FL_TRIGGER_COND)
 419                 *tt = event_triggers_call(file, entry);
 420
 421         if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags))
 422                 ring_buffer_discard_commit(buffer, event);
 423         else if (!filter_check_discard(file, entry, buffer, event))
 424                 return false;
 425
 426         return true;
 427 }
 428
 429 /**
 430  * event_trigger_unlock_commit - handle triggers and finish event commit
 431  * @file: The file pointer assoctiated to the event
 432  * @buffer: The ring buffer that the event is being written to
 433  * @event: The event meta data in the ring buffer
 434  * @entry: The event itself
 435  * @irq_flags: The state of the interrupts at the start of the event
 436  * @pc: The state of the preempt count at the start of the event.
 437  *
 438  * This is a helper function to handle triggers that require data
 439  * from the event itself. It also tests the event against filters and
 440  * if the event is soft disabled and should be discarded.
 441  */
 442 static inline void
 443 event_trigger_unlock_commit(struct ftrace_event_file *file,
 444                             struct ring_buffer *buffer,
 445                             struct ring_buffer_event *event,
 446                             void *entry, unsigned long irq_flags, int pc)
 447 {
 448         enum event_trigger_type tt = ETT_NONE;
 449
 450         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
 451                 trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
 452
 453         if (tt)
 454                 event_triggers_post_call(file, tt);
 455 }
 456
 457 /**
 458  * event_trigger_unlock_commit_regs - handle triggers and finish event commit
 459  * @file: The file pointer assoctiated to the event
 460  * @buffer: The ring buffer that the event is being written to
 461  * @event: The event meta data in the ring buffer
 462  * @entry: The event itself
 463  * @irq_flags: The state of the interrupts at the start of the event
 464  * @pc: The state of the preempt count at the start of the event.
 465  *
 466  * This is a helper function to handle triggers that require data
 467  * from the event itself. It also tests the event against filters and
 468  * if the event is soft disabled and should be discarded.
 469  *
 470  * Same as event_trigger_unlock_commit() but calls
 471  * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
 472  */
 473 static inline void
 474 event_trigger_unlock_commit_regs(struct ftrace_event_file *file,
 475                                  struct ring_buffer *buffer,
 476                                  struct ring_buffer_event *event,
 477                                  void *entry, unsigned long irq_flags, int pc,
 478                                  struct pt_regs *regs)
 479 {
 480         enum event_trigger_type tt = ETT_NONE;
 481
 482         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
 483                 trace_buffer_unlock_commit_regs(buffer, event,
 484                                                 irq_flags, pc, regs);
 485
 486         if (tt)
 487                 event_triggers_post_call(file, tt);
 488 }
 489
 490 enum {
 491         FILTER_OTHER = 0,
 492         FILTER_STATIC_STRING,
 493         FILTER_DYN_STRING,
 494         FILTER_PTR_STRING,
 495         FILTER_TRACE_FN,
 496 };
 497
 498 extern int trace_event_raw_init(struct ftrace_event_call *call);
 499 extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 500                               const char *name, int offset, int size,
 501                               int is_signed, int filter_type);
 502 extern int trace_add_event_call(struct ftrace_event_call *call);
 503 extern int trace_remove_event_call(struct ftrace_event_call *call);
 504
 505 #define is_signed_type(type)    (((type)(-1)) < (type)1)
 506
 507 int trace_set_clr_event(const char *system, const char *event, int set);
 508
 509 /*
 510  * The double __builtin_constant_p is because gcc will give us an error
 511  * if we try to allocate the static variable to fmt if it is not a
 512  * constant. Even with the outer if statement optimizing out.
 513  */
 514 #define event_trace_printk(ip, fmt, args...)                            \
 515 do {                                                                    \
 516         __trace_printk_check_format(fmt, ##args);                       \
 517         tracing_record_cmdline(current);                                \
 518         if (__builtin_constant_p(fmt)) {                                \
 519                 static const char *trace_printk_fmt                     \
 520                   __attribute__((section("__trace_printk_fmt"))) =      \
 521                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 522                                                                         \
 523                 __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 524         } else                                                          \
 525                 __trace_printk(ip, fmt, ##args);                        \
 526 } while (0)
 527
 528 /**
 529  * tracepoint_string - register constant persistent string to trace system
 530  * @str - a constant persistent string that will be referenced in tracepoints
 531  *
 532  * If constant strings are being used in tracepoints, it is faster and
 533  * more efficient to just save the pointer to the string and reference
 534  * that with a printf "%s" instead of saving the string in the ring buffer
 535  * and wasting space and time.
 536  *
 537  * The problem with the above approach is that userspace tools that read
 538  * the binary output of the trace buffers do not have access to the string.
 539  * Instead they just show the address of the string which is not very
 540  * useful to users.
 541  *
 542  * With tracepoint_string(), the string will be registered to the tracing
 543  * system and exported to userspace via the debugfs/tracing/printk_formats
 544  * file that maps the string address to the string text. This way userspace
 545  * tools that read the binary buffers have a way to map the pointers to
 546  * the ASCII strings they represent.
 547  *
 548  * The @str used must be a constant string and persistent as it would not
 549  * make sense to show a string that no longer exists. But it is still fine
 550  * to be used with modules, because when modules are unloaded, if they
 551  * had tracepoints, the ring buffers are cleared too. As long as the string
 552  * does not change during the life of the module, it is fine to use
 553  * tracepoint_string() within a module.
 554  */
 555 #define tracepoint_string(str)                                          \
 556         ({                                                              \
 557                 static const char *___tp_str __tracepoint_string = str; \
 558                 ___tp_str;                                              \
 559         })
 560 #define __tracepoint_string     __attribute__((section("__tracepoint_str")))
 561
 562 #ifdef CONFIG_PERF_EVENTS
 563 struct perf_event;
 564
 565 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 566
 567 extern int  perf_trace_init(struct perf_event *event);
 568 extern void perf_trace_destroy(struct perf_event *event);
 569 extern int  perf_trace_add(struct perf_event *event, int flags);
 570 extern void perf_trace_del(struct perf_event *event, int flags);
 571 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
 572                                      char *filter_str);
 573 extern void ftrace_profile_free_filter(struct perf_event *event);
 574 extern void *perf_trace_buf_prepare(int size, unsigned short type,
 575                                     struct pt_regs *regs, int *rctxp);
 576
 577 static inline void
 578 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 579                        u64 count, struct pt_regs *regs, void *head,
 580                        struct task_struct *task)
 581 {
 582         perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
 583 }
 584 #endif
 585
 586 #endif /* _LINUX_FTRACE_EVENT_H */