kernel/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 #include <linux/tracepoint.h>
  11
  12 struct trace_array;
  13 struct trace_buffer;
  14 struct tracer;
  15 struct dentry;
  16 struct bpf_prog;
  17
  18 struct trace_print_flags {
  19         unsigned long           mask;
  20         const char              *name;
  21 };
  22
  23 struct trace_print_flags_u64 {
  24         unsigned long long      mask;
  25         const char              *name;
  26 };
  27
  28 const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  29                                    unsigned long flags,
  30                                    const struct trace_print_flags *flag_array);
  31
  32 const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  33                                      const struct trace_print_flags *symbol_array);
  34
  35 #if BITS_PER_LONG == 32
  36 const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
  37                                          unsigned long long val,
  38                                          const struct trace_print_flags_u64
  39                                                                  *symbol_array);
  40 #endif
  41
  42 const char *ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
  43                                      unsigned int bitmask_size);
  44
  45 const char *ftrace_print_hex_seq(struct trace_seq *p,
  46                                  const unsigned char *buf, int len);
  47
  48 const char *ftrace_print_array_seq(struct trace_seq *p,
  49                                    const void *buf, int count,
  50                                    size_t el_size);
  51
  52 struct trace_iterator;
  53 struct trace_event;
  54
  55 int ftrace_raw_output_prep(struct trace_iterator *iter,
  56                            struct trace_event *event);
  57
  58 /*
  59  * The trace entry - the most basic unit of tracing. This is what
  60  * is printed in the end as a single line in the trace output, such as:
  61  *
  62  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  63  */
  64 struct trace_entry {
  65         unsigned short          type;
  66         unsigned char           flags;
  67         unsigned char           preempt_count;
  68         int                     pid;
  69         unsigned short          migrate_disable;
  70         unsigned short          padding;
  71         unsigned char           preempt_lazy_count;
  72 };
  73
  74 #define FTRACE_MAX_EVENT                                                \
  75         ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
  76
  77 /*
  78  * Trace iterator - used by printout routines who present trace
  79  * results to users and which routines might sleep, etc:
  80  */
  81 struct trace_iterator {
  82         struct trace_array      *tr;
  83         struct tracer           *trace;
  84         struct trace_buffer     *trace_buffer;
  85         void                    *private;
  86         int                     cpu_file;
  87         struct mutex            mutex;
  88         struct ring_buffer_iter **buffer_iter;
  89         unsigned long           iter_flags;
  90
  91         /* trace_seq for __print_flags() and __print_symbolic() etc. */
  92         struct trace_seq        tmp_seq;
  93
  94         cpumask_var_t           started;
  95
  96         /* it's true when current open file is snapshot */
  97         bool                    snapshot;
  98
  99         /* The below is zeroed out in pipe_read */
 100         struct trace_seq        seq;
 101         struct trace_entry      *ent;
 102         unsigned long           lost_events;
 103         int                     leftover;
 104         int                     ent_size;
 105         int                     cpu;
 106         u64                     ts;
 107
 108         loff_t                  pos;
 109         long                    idx;
 110
 111         /* All new field here will be zeroed out in pipe_read */
 112 };
 113
 114 enum trace_iter_flags {
 115         TRACE_FILE_LAT_FMT      = 1,
 116         TRACE_FILE_ANNOTATE     = 2,
 117         TRACE_FILE_TIME_IN_NS   = 4,
 118 };
 119
 120
 121 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
 122                                       int flags, struct trace_event *event);
 123
 124 struct trace_event_functions {
 125         trace_print_func        trace;
 126         trace_print_func        raw;
 127         trace_print_func        hex;
 128         trace_print_func        binary;
 129 };
 130
 131 struct trace_event {
 132         struct hlist_node               node;
 133         struct list_head                list;
 134         int                             type;
 135         struct trace_event_functions    *funcs;
 136 };
 137
 138 extern int register_ftrace_event(struct trace_event *event);
 139 extern int unregister_ftrace_event(struct trace_event *event);
 140
 141 /* Return values for print_line callback */
 142 enum print_line_t {
 143         TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
 144         TRACE_TYPE_HANDLED      = 1,
 145         TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
 146         TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
 147 };
 148
 149 /*
 150  * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
 151  * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
 152  * simplifies those functions and keeps them in sync.
 153  */
 154 static inline enum print_line_t trace_handle_return(struct trace_seq *s)
 155 {
 156         return trace_seq_has_overflowed(s) ?
 157                 TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
 158 }
 159
 160 void tracing_generic_entry_update(struct trace_entry *entry,
 161                                   unsigned long flags,
 162                                   int pc);
 163 struct ftrace_event_file;
 164
 165 struct ring_buffer_event *
 166 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
 167                                 struct ftrace_event_file *ftrace_file,
 168                                 int type, unsigned long len,
 169                                 unsigned long flags, int pc);
 170 struct ring_buffer_event *
 171 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
 172                                   int type, unsigned long len,
 173                                   unsigned long flags, int pc);
 174 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 175                                         struct ring_buffer_event *event,
 176                                         unsigned long flags, int pc);
 177 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 178                                 struct ring_buffer_event *event,
 179                                 unsigned long flags, int pc);
 180 void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
 181                                      struct ring_buffer_event *event,
 182                                      unsigned long flags, int pc,
 183                                      struct pt_regs *regs);
 184 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 185                                          struct ring_buffer_event *event);
 186
 187 void tracing_record_cmdline(struct task_struct *tsk);
 188
 189 int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...);
 190
 191 struct event_filter;
 192
 193 enum trace_reg {
 194         TRACE_REG_REGISTER,
 195         TRACE_REG_UNREGISTER,
 196 #ifdef CONFIG_PERF_EVENTS
 197         TRACE_REG_PERF_REGISTER,
 198         TRACE_REG_PERF_UNREGISTER,
 199         TRACE_REG_PERF_OPEN,
 200         TRACE_REG_PERF_CLOSE,
 201         TRACE_REG_PERF_ADD,
 202         TRACE_REG_PERF_DEL,
 203 #endif
 204 };
 205
 206 struct ftrace_event_call;
 207
 208 struct ftrace_event_class {
 209         const char              *system;
 210         void                    *probe;
 211 #ifdef CONFIG_PERF_EVENTS
 212         void                    *perf_probe;
 213 #endif
 214         int                     (*reg)(struct ftrace_event_call *event,
 215                                        enum trace_reg type, void *data);
 216         int                     (*define_fields)(struct ftrace_event_call *);
 217         struct list_head        *(*get_fields)(struct ftrace_event_call *);
 218         struct list_head        fields;
 219         int                     (*raw_init)(struct ftrace_event_call *);
 220 };
 221
 222 extern int ftrace_event_reg(struct ftrace_event_call *event,
 223                             enum trace_reg type, void *data);
 224
 225 int ftrace_output_event(struct trace_iterator *iter, struct ftrace_event_call *event,
 226                         char *fmt, ...);
 227
 228 int ftrace_event_define_field(struct ftrace_event_call *call,
 229                               char *type, int len, char *item, int offset,
 230                               int field_size, int sign, int filter);
 231
 232 struct ftrace_event_buffer {
 233         struct ring_buffer              *buffer;
 234         struct ring_buffer_event        *event;
 235         struct ftrace_event_file        *ftrace_file;
 236         void                            *entry;
 237         unsigned long                   flags;
 238         int                             pc;
 239 };
 240
 241 void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer,
 242                                   struct ftrace_event_file *ftrace_file,
 243                                   unsigned long len);
 244
 245 void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer);
 246
 247 int ftrace_event_define_field(struct ftrace_event_call *call,
 248                               char *type, int len, char *item, int offset,
 249                               int field_size, int sign, int filter);
 250
 251 enum {
 252         TRACE_EVENT_FL_FILTERED_BIT,
 253         TRACE_EVENT_FL_CAP_ANY_BIT,
 254         TRACE_EVENT_FL_NO_SET_FILTER_BIT,
 255         TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
 256         TRACE_EVENT_FL_WAS_ENABLED_BIT,
 257         TRACE_EVENT_FL_USE_CALL_FILTER_BIT,
 258         TRACE_EVENT_FL_TRACEPOINT_BIT,
 259         TRACE_EVENT_FL_KPROBE_BIT,
 260 };
 261
 262 /*
 263  * Event flags:
 264  *  FILTERED      - The event has a filter attached
 265  *  CAP_ANY       - Any user can enable for perf
 266  *  NO_SET_FILTER - Set when filter has error and is to be ignored
 267  *  IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
 268  *  WAS_ENABLED   - Set and stays set when an event was ever enabled
 269  *                    (used for module unloading, if a module event is enabled,
 270  *                     it is best to clear the buffers that used it).
 271  *  USE_CALL_FILTER - For ftrace internal events, don't use file filter
 272  *  TRACEPOINT    - Event is a tracepoint
 273  *  KPROBE        - Event is a kprobe
 274  */
 275 enum {
 276         TRACE_EVENT_FL_FILTERED         = (1 << TRACE_EVENT_FL_FILTERED_BIT),
 277         TRACE_EVENT_FL_CAP_ANY          = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
 278         TRACE_EVENT_FL_NO_SET_FILTER    = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
 279         TRACE_EVENT_FL_IGNORE_ENABLE    = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
 280         TRACE_EVENT_FL_WAS_ENABLED      = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
 281         TRACE_EVENT_FL_USE_CALL_FILTER  = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT),
 282         TRACE_EVENT_FL_TRACEPOINT       = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
 283         TRACE_EVENT_FL_KPROBE           = (1 << TRACE_EVENT_FL_KPROBE_BIT),
 284 };
 285
 286 struct ftrace_event_call {
 287         struct list_head        list;
 288         struct ftrace_event_class *class;
 289         union {
 290                 char                    *name;
 291                 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
 292                 struct tracepoint       *tp;
 293         };
 294         struct trace_event      event;
 295         char                    *print_fmt;
 296         struct event_filter     *filter;
 297         void                    *mod;
 298         void                    *data;
 299         /*
 300          *   bit 0:             filter_active
 301          *   bit 1:             allow trace by non root (cap any)
 302          *   bit 2:             failed to apply filter
 303          *   bit 3:             ftrace internal event (do not enable)
 304          *   bit 4:             Event was enabled by module
 305          *   bit 5:             use call filter rather than file filter
 306          *   bit 6:             Event is a tracepoint
 307          */
 308         int                     flags; /* static flags of different events */
 309
 310 #ifdef CONFIG_PERF_EVENTS
 311         int                             perf_refcount;
 312         struct hlist_head __percpu      *perf_events;
 313         struct bpf_prog                 *prog;
 314
 315         int     (*perf_perm)(struct ftrace_event_call *,
 316                              struct perf_event *);
 317 #endif
 318 };
 319
 320 static inline const char *
 321 ftrace_event_name(struct ftrace_event_call *call)
 322 {
 323         if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
 324                 return call->tp ? call->tp->name : NULL;
 325         else
 326                 return call->name;
 327 }
 328
 329 struct trace_array;
 330 struct ftrace_subsystem_dir;
 331
 332 enum {
 333         FTRACE_EVENT_FL_ENABLED_BIT,
 334         FTRACE_EVENT_FL_RECORDED_CMD_BIT,
 335         FTRACE_EVENT_FL_FILTERED_BIT,
 336         FTRACE_EVENT_FL_NO_SET_FILTER_BIT,
 337         FTRACE_EVENT_FL_SOFT_MODE_BIT,
 338         FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
 339         FTRACE_EVENT_FL_TRIGGER_MODE_BIT,
 340         FTRACE_EVENT_FL_TRIGGER_COND_BIT,
 341 };
 342
 343 /*
 344  * Ftrace event file flags:
 345  *  ENABLED       - The event is enabled
 346  *  RECORDED_CMD  - The comms should be recorded at sched_switch
 347  *  FILTERED      - The event has a filter attached
 348  *  NO_SET_FILTER - Set when filter has error and is to be ignored
 349  *  SOFT_MODE     - The event is enabled/disabled by SOFT_DISABLED
 350  *  SOFT_DISABLED - When set, do not trace the event (even though its
 351  *                   tracepoint may be enabled)
 352  *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
 353  *  TRIGGER_COND  - When set, one or more triggers has an associated filter
 354  */
 355 enum {
 356         FTRACE_EVENT_FL_ENABLED         = (1 << FTRACE_EVENT_FL_ENABLED_BIT),
 357         FTRACE_EVENT_FL_RECORDED_CMD    = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT),
 358         FTRACE_EVENT_FL_FILTERED        = (1 << FTRACE_EVENT_FL_FILTERED_BIT),
 359         FTRACE_EVENT_FL_NO_SET_FILTER   = (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT),
 360         FTRACE_EVENT_FL_SOFT_MODE       = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT),
 361         FTRACE_EVENT_FL_SOFT_DISABLED   = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT),
 362         FTRACE_EVENT_FL_TRIGGER_MODE    = (1 << FTRACE_EVENT_FL_TRIGGER_MODE_BIT),
 363         FTRACE_EVENT_FL_TRIGGER_COND    = (1 << FTRACE_EVENT_FL_TRIGGER_COND_BIT),
 364 };
 365
 366 struct ftrace_event_file {
 367         struct list_head                list;
 368         struct ftrace_event_call        *event_call;
 369         struct event_filter             *filter;
 370         struct dentry                   *dir;
 371         struct trace_array              *tr;
 372         struct ftrace_subsystem_dir     *system;
 373         struct list_head                triggers;
 374
 375         /*
 376          * 32 bit flags:
 377          *   bit 0:             enabled
 378          *   bit 1:             enabled cmd record
 379          *   bit 2:             enable/disable with the soft disable bit
 380          *   bit 3:             soft disabled
 381          *   bit 4:             trigger enabled
 382          *
 383          * Note: The bits must be set atomically to prevent races
 384          * from other writers. Reads of flags do not need to be in
 385          * sync as they occur in critical sections. But the way flags
 386          * is currently used, these changes do not affect the code
 387          * except that when a change is made, it may have a slight
 388          * delay in propagating the changes to other CPUs due to
 389          * caching and such. Which is mostly OK ;-)
 390          */
 391         unsigned long           flags;
 392         atomic_t                sm_ref; /* soft-mode reference counter */
 393         atomic_t                tm_ref; /* trigger-mode reference counter */
 394 };
 395
 396 #define __TRACE_EVENT_FLAGS(name, value)                                \
 397         static int __init trace_init_flags_##name(void)                 \
 398         {                                                               \
 399                 event_##name.flags |= value;                            \
 400                 return 0;                                               \
 401         }                                                               \
 402         early_initcall(trace_init_flags_##name);
 403
 404 #define __TRACE_EVENT_PERF_PERM(name, expr...)                          \
 405         static int perf_perm_##name(struct ftrace_event_call *tp_event, \
 406                                     struct perf_event *p_event)         \
 407         {                                                               \
 408                 return ({ expr; });                                     \
 409         }                                                               \
 410         static int __init trace_init_perf_perm_##name(void)             \
 411         {                                                               \
 412                 event_##name.perf_perm = &perf_perm_##name;             \
 413                 return 0;                                               \
 414         }                                                               \
 415         early_initcall(trace_init_perf_perm_##name);
 416
 417 #define PERF_MAX_TRACE_SIZE     2048
 418
 419 #define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
 420
 421 enum event_trigger_type {
 422         ETT_NONE                = (0),
 423         ETT_TRACE_ONOFF         = (1 << 0),
 424         ETT_SNAPSHOT            = (1 << 1),
 425         ETT_STACKTRACE          = (1 << 2),
 426         ETT_EVENT_ENABLE        = (1 << 3),
 427 };
 428
 429 extern int filter_match_preds(struct event_filter *filter, void *rec);
 430
 431 extern int filter_check_discard(struct ftrace_event_file *file, void *rec,
 432                                 struct ring_buffer *buffer,
 433                                 struct ring_buffer_event *event);
 434 extern int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
 435                                      struct ring_buffer *buffer,
 436                                      struct ring_buffer_event *event);
 437 extern enum event_trigger_type event_triggers_call(struct ftrace_event_file *file,
 438                                                    void *rec);
 439 extern void event_triggers_post_call(struct ftrace_event_file *file,
 440                                      enum event_trigger_type tt);
 441
 442 /**
 443  * ftrace_trigger_soft_disabled - do triggers and test if soft disabled
 444  * @file: The file pointer of the event to test
 445  *
 446  * If any triggers without filters are attached to this event, they
 447  * will be called here. If the event is soft disabled and has no
 448  * triggers that require testing the fields, it will return true,
 449  * otherwise false.
 450  */
 451 static inline bool
 452 ftrace_trigger_soft_disabled(struct ftrace_event_file *file)
 453 {
 454         unsigned long eflags = file->flags;
 455
 456         if (!(eflags & FTRACE_EVENT_FL_TRIGGER_COND)) {
 457                 if (eflags & FTRACE_EVENT_FL_TRIGGER_MODE)
 458                         event_triggers_call(file, NULL);
 459                 if (eflags & FTRACE_EVENT_FL_SOFT_DISABLED)
 460                         return true;
 461         }
 462         return false;
 463 }
 464
 465 /*
 466  * Helper function for event_trigger_unlock_commit{_regs}().
 467  * If there are event triggers attached to this event that requires
 468  * filtering against its fields, then they wil be called as the
 469  * entry already holds the field information of the current event.
 470  *
 471  * It also checks if the event should be discarded or not.
 472  * It is to be discarded if the event is soft disabled and the
 473  * event was only recorded to process triggers, or if the event
 474  * filter is active and this event did not match the filters.
 475  *
 476  * Returns true if the event is discarded, false otherwise.
 477  */
 478 static inline bool
 479 __event_trigger_test_discard(struct ftrace_event_file *file,
 480                              struct ring_buffer *buffer,
 481                              struct ring_buffer_event *event,
 482                              void *entry,
 483                              enum event_trigger_type *tt)
 484 {
 485         unsigned long eflags = file->flags;
 486
 487         if (eflags & FTRACE_EVENT_FL_TRIGGER_COND)
 488                 *tt = event_triggers_call(file, entry);
 489
 490         if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags))
 491                 ring_buffer_discard_commit(buffer, event);
 492         else if (!filter_check_discard(file, entry, buffer, event))
 493                 return false;
 494
 495         return true;
 496 }
 497
 498 /**
 499  * event_trigger_unlock_commit - handle triggers and finish event commit
 500  * @file: The file pointer assoctiated to the event
 501  * @buffer: The ring buffer that the event is being written to
 502  * @event: The event meta data in the ring buffer
 503  * @entry: The event itself
 504  * @irq_flags: The state of the interrupts at the start of the event
 505  * @pc: The state of the preempt count at the start of the event.
 506  *
 507  * This is a helper function to handle triggers that require data
 508  * from the event itself. It also tests the event against filters and
 509  * if the event is soft disabled and should be discarded.
 510  */
 511 static inline void
 512 event_trigger_unlock_commit(struct ftrace_event_file *file,
 513                             struct ring_buffer *buffer,
 514                             struct ring_buffer_event *event,
 515                             void *entry, unsigned long irq_flags, int pc)
 516 {
 517         enum event_trigger_type tt = ETT_NONE;
 518
 519         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
 520                 trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
 521
 522         if (tt)
 523                 event_triggers_post_call(file, tt);
 524 }
 525
 526 /**
 527  * event_trigger_unlock_commit_regs - handle triggers and finish event commit
 528  * @file: The file pointer assoctiated to the event
 529  * @buffer: The ring buffer that the event is being written to
 530  * @event: The event meta data in the ring buffer
 531  * @entry: The event itself
 532  * @irq_flags: The state of the interrupts at the start of the event
 533  * @pc: The state of the preempt count at the start of the event.
 534  *
 535  * This is a helper function to handle triggers that require data
 536  * from the event itself. It also tests the event against filters and
 537  * if the event is soft disabled and should be discarded.
 538  *
 539  * Same as event_trigger_unlock_commit() but calls
 540  * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
 541  */
 542 static inline void
 543 event_trigger_unlock_commit_regs(struct ftrace_event_file *file,
 544                                  struct ring_buffer *buffer,
 545                                  struct ring_buffer_event *event,
 546                                  void *entry, unsigned long irq_flags, int pc,
 547                                  struct pt_regs *regs)
 548 {
 549         enum event_trigger_type tt = ETT_NONE;
 550
 551         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
 552                 trace_buffer_unlock_commit_regs(buffer, event,
 553                                                 irq_flags, pc, regs);
 554
 555         if (tt)
 556                 event_triggers_post_call(file, tt);
 557 }
 558
 559 #ifdef CONFIG_BPF_SYSCALL
 560 unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx);
 561 #else
 562 static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx)
 563 {
 564         return 1;
 565 }
 566 #endif
 567
 568 enum {
 569         FILTER_OTHER = 0,
 570         FILTER_STATIC_STRING,
 571         FILTER_DYN_STRING,
 572         FILTER_PTR_STRING,
 573         FILTER_TRACE_FN,
 574 };
 575
 576 extern int trace_event_raw_init(struct ftrace_event_call *call);
 577 extern int trace_define_field(struct ftrace_event_call *call, const char *type,
 578                               const char *name, int offset, int size,
 579                               int is_signed, int filter_type);
 580 extern int trace_add_event_call(struct ftrace_event_call *call);
 581 extern int trace_remove_event_call(struct ftrace_event_call *call);
 582
 583 #define is_signed_type(type)    (((type)(-1)) < (type)1)
 584
 585 int trace_set_clr_event(const char *system, const char *event, int set);
 586
 587 /*
 588  * The double __builtin_constant_p is because gcc will give us an error
 589  * if we try to allocate the static variable to fmt if it is not a
 590  * constant. Even with the outer if statement optimizing out.
 591  */
 592 #define event_trace_printk(ip, fmt, args...)                            \
 593 do {                                                                    \
 594         __trace_printk_check_format(fmt, ##args);                       \
 595         tracing_record_cmdline(current);                                \
 596         if (__builtin_constant_p(fmt)) {                                \
 597                 static const char *trace_printk_fmt                     \
 598                   __attribute__((section("__trace_printk_fmt"))) =      \
 599                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 600                                                                         \
 601                 __trace_bprintk(ip, trace_printk_fmt, ##args);          \
 602         } else                                                          \
 603                 __trace_printk(ip, fmt, ##args);                        \
 604 } while (0)
 605
 606 #ifdef CONFIG_PERF_EVENTS
 607 struct perf_event;
 608
 609 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
 610
 611 extern int  perf_trace_init(struct perf_event *event);
 612 extern void perf_trace_destroy(struct perf_event *event);
 613 extern int  perf_trace_add(struct perf_event *event, int flags);
 614 extern void perf_trace_del(struct perf_event *event, int flags);
 615 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
 616                                      char *filter_str);
 617 extern void ftrace_profile_free_filter(struct perf_event *event);
 618 extern void *perf_trace_buf_prepare(int size, unsigned short type,
 619                                     struct pt_regs **regs, int *rctxp);
 620
 621 static inline void
 622 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
 623                        u64 count, struct pt_regs *regs, void *head,
 624                        struct task_struct *task)
 625 {
 626         perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
 627 }
 628 #endif
 629
 630 #endif /* _LINUX_FTRACE_EVENT_H */