2 #ifndef _LINUX_TRACE_EVENT_H
3 #define _LINUX_TRACE_EVENT_H
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>
18 struct trace_print_flags
{
23 struct trace_print_flags_u64
{
24 unsigned long long mask
;
28 const char *trace_print_flags_seq(struct trace_seq
*p
, const char *delim
,
30 const struct trace_print_flags
*flag_array
);
32 const char *trace_print_symbols_seq(struct trace_seq
*p
, unsigned long val
,
33 const struct trace_print_flags
*symbol_array
);
35 #if BITS_PER_LONG == 32
36 const char *trace_print_symbols_seq_u64(struct trace_seq
*p
,
37 unsigned long long val
,
38 const struct trace_print_flags_u64
42 const char *trace_print_bitmask_seq(struct trace_seq
*p
, void *bitmask_ptr
,
43 unsigned int bitmask_size
);
45 const char *trace_print_hex_seq(struct trace_seq
*p
,
46 const unsigned char *buf
, int len
);
48 const char *trace_print_array_seq(struct trace_seq
*p
,
49 const void *buf
, int count
,
52 struct trace_iterator
;
55 int trace_raw_output_prep(struct trace_iterator
*iter
,
56 struct trace_event
*event
);
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:
62 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
67 unsigned char preempt_count
;
71 #define TRACE_EVENT_TYPE_MAX \
72 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
75 * Trace iterator - used by printout routines who present trace
76 * results to users and which routines might sleep, etc:
78 struct trace_iterator
{
79 struct trace_array
*tr
;
81 struct trace_buffer
*trace_buffer
;
85 struct ring_buffer_iter
**buffer_iter
;
86 unsigned long iter_flags
;
88 /* trace_seq for __print_flags() and __print_symbolic() etc. */
89 struct trace_seq tmp_seq
;
91 cpumask_var_t started
;
93 /* it's true when current open file is snapshot */
96 /* The below is zeroed out in pipe_read */
98 struct trace_entry
*ent
;
99 unsigned long lost_events
;
108 /* All new field here will be zeroed out in pipe_read */
111 enum trace_iter_flags
{
112 TRACE_FILE_LAT_FMT
= 1,
113 TRACE_FILE_ANNOTATE
= 2,
114 TRACE_FILE_TIME_IN_NS
= 4,
118 typedef enum print_line_t (*trace_print_func
)(struct trace_iterator
*iter
,
119 int flags
, struct trace_event
*event
);
121 struct trace_event_functions
{
122 trace_print_func trace
;
123 trace_print_func raw
;
124 trace_print_func hex
;
125 trace_print_func binary
;
129 struct hlist_node node
;
130 struct list_head list
;
132 struct trace_event_functions
*funcs
;
135 extern int register_trace_event(struct trace_event
*event
);
136 extern int unregister_trace_event(struct trace_event
*event
);
138 /* Return values for print_line callback */
140 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
141 TRACE_TYPE_HANDLED
= 1,
142 TRACE_TYPE_UNHANDLED
= 2, /* Relay to other output functions */
143 TRACE_TYPE_NO_CONSUME
= 3 /* Handled but ask to not consume */
147 * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
148 * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
149 * simplifies those functions and keeps them in sync.
151 static inline enum print_line_t
trace_handle_return(struct trace_seq
*s
)
153 return trace_seq_has_overflowed(s
) ?
154 TRACE_TYPE_PARTIAL_LINE
: TRACE_TYPE_HANDLED
;
157 void tracing_generic_entry_update(struct trace_entry
*entry
,
160 struct trace_event_file
;
162 struct ring_buffer_event
*
163 trace_event_buffer_lock_reserve(struct ring_buffer
**current_buffer
,
164 struct trace_event_file
*trace_file
,
165 int type
, unsigned long len
,
166 unsigned long flags
, int pc
);
167 struct ring_buffer_event
*
168 trace_current_buffer_lock_reserve(struct ring_buffer
**current_buffer
,
169 int type
, unsigned long len
,
170 unsigned long flags
, int pc
);
171 void trace_buffer_unlock_commit(struct trace_array
*tr
,
172 struct ring_buffer
*buffer
,
173 struct ring_buffer_event
*event
,
174 unsigned long flags
, int pc
);
175 void trace_buffer_unlock_commit_regs(struct trace_array
*tr
,
176 struct ring_buffer
*buffer
,
177 struct ring_buffer_event
*event
,
178 unsigned long flags
, int pc
,
179 struct pt_regs
*regs
);
180 void trace_current_buffer_discard_commit(struct ring_buffer
*buffer
,
181 struct ring_buffer_event
*event
);
183 void tracing_record_cmdline(struct task_struct
*tsk
);
185 int trace_output_call(struct trace_iterator
*iter
, char *name
, char *fmt
, ...);
191 TRACE_REG_UNREGISTER
,
192 #ifdef CONFIG_PERF_EVENTS
193 TRACE_REG_PERF_REGISTER
,
194 TRACE_REG_PERF_UNREGISTER
,
196 TRACE_REG_PERF_CLOSE
,
202 struct trace_event_call
;
204 struct trace_event_class
{
207 #ifdef CONFIG_PERF_EVENTS
210 int (*reg
)(struct trace_event_call
*event
,
211 enum trace_reg type
, void *data
);
212 int (*define_fields
)(struct trace_event_call
*);
213 struct list_head
*(*get_fields
)(struct trace_event_call
*);
214 struct list_head fields
;
215 int (*raw_init
)(struct trace_event_call
*);
218 extern int trace_event_reg(struct trace_event_call
*event
,
219 enum trace_reg type
, void *data
);
221 struct trace_event_buffer
{
222 struct ring_buffer
*buffer
;
223 struct ring_buffer_event
*event
;
224 struct trace_event_file
*trace_file
;
230 void *trace_event_buffer_reserve(struct trace_event_buffer
*fbuffer
,
231 struct trace_event_file
*trace_file
,
234 void trace_event_buffer_commit(struct trace_event_buffer
*fbuffer
);
237 TRACE_EVENT_FL_FILTERED_BIT
,
238 TRACE_EVENT_FL_CAP_ANY_BIT
,
239 TRACE_EVENT_FL_NO_SET_FILTER_BIT
,
240 TRACE_EVENT_FL_IGNORE_ENABLE_BIT
,
241 TRACE_EVENT_FL_WAS_ENABLED_BIT
,
242 TRACE_EVENT_FL_USE_CALL_FILTER_BIT
,
243 TRACE_EVENT_FL_TRACEPOINT_BIT
,
244 TRACE_EVENT_FL_KPROBE_BIT
,
245 TRACE_EVENT_FL_UPROBE_BIT
,
250 * FILTERED - The event has a filter attached
251 * CAP_ANY - Any user can enable for perf
252 * NO_SET_FILTER - Set when filter has error and is to be ignored
253 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
254 * WAS_ENABLED - Set and stays set when an event was ever enabled
255 * (used for module unloading, if a module event is enabled,
256 * it is best to clear the buffers that used it).
257 * USE_CALL_FILTER - For trace internal events, don't use file filter
258 * TRACEPOINT - Event is a tracepoint
259 * KPROBE - Event is a kprobe
260 * UPROBE - Event is a uprobe
263 TRACE_EVENT_FL_FILTERED
= (1 << TRACE_EVENT_FL_FILTERED_BIT
),
264 TRACE_EVENT_FL_CAP_ANY
= (1 << TRACE_EVENT_FL_CAP_ANY_BIT
),
265 TRACE_EVENT_FL_NO_SET_FILTER
= (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT
),
266 TRACE_EVENT_FL_IGNORE_ENABLE
= (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT
),
267 TRACE_EVENT_FL_WAS_ENABLED
= (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT
),
268 TRACE_EVENT_FL_USE_CALL_FILTER
= (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT
),
269 TRACE_EVENT_FL_TRACEPOINT
= (1 << TRACE_EVENT_FL_TRACEPOINT_BIT
),
270 TRACE_EVENT_FL_KPROBE
= (1 << TRACE_EVENT_FL_KPROBE_BIT
),
271 TRACE_EVENT_FL_UPROBE
= (1 << TRACE_EVENT_FL_UPROBE_BIT
),
274 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
276 struct trace_event_call
{
277 struct list_head list
;
278 struct trace_event_class
*class;
281 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
282 struct tracepoint
*tp
;
284 struct trace_event event
;
286 struct event_filter
*filter
;
290 * bit 0: filter_active
291 * bit 1: allow trace by non root (cap any)
292 * bit 2: failed to apply filter
293 * bit 3: trace internal event (do not enable)
294 * bit 4: Event was enabled by module
295 * bit 5: use call filter rather than file filter
296 * bit 6: Event is a tracepoint
298 int flags
; /* static flags of different events */
300 #ifdef CONFIG_PERF_EVENTS
302 struct hlist_head __percpu
*perf_events
;
303 struct bpf_prog
*prog
;
305 int (*perf_perm
)(struct trace_event_call
*,
306 struct perf_event
*);
310 static inline const char *
311 trace_event_name(struct trace_event_call
*call
)
313 if (call
->flags
& TRACE_EVENT_FL_TRACEPOINT
)
314 return call
->tp
? call
->tp
->name
: NULL
;
320 struct trace_subsystem_dir
;
323 EVENT_FILE_FL_ENABLED_BIT
,
324 EVENT_FILE_FL_RECORDED_CMD_BIT
,
325 EVENT_FILE_FL_FILTERED_BIT
,
326 EVENT_FILE_FL_NO_SET_FILTER_BIT
,
327 EVENT_FILE_FL_SOFT_MODE_BIT
,
328 EVENT_FILE_FL_SOFT_DISABLED_BIT
,
329 EVENT_FILE_FL_TRIGGER_MODE_BIT
,
330 EVENT_FILE_FL_TRIGGER_COND_BIT
,
331 EVENT_FILE_FL_PID_FILTER_BIT
,
336 * ENABLED - The event is enabled
337 * RECORDED_CMD - The comms should be recorded at sched_switch
338 * FILTERED - The event has a filter attached
339 * NO_SET_FILTER - Set when filter has error and is to be ignored
340 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
341 * SOFT_DISABLED - When set, do not trace the event (even though its
342 * tracepoint may be enabled)
343 * TRIGGER_MODE - When set, invoke the triggers associated with the event
344 * TRIGGER_COND - When set, one or more triggers has an associated filter
345 * PID_FILTER - When set, the event is filtered based on pid
348 EVENT_FILE_FL_ENABLED
= (1 << EVENT_FILE_FL_ENABLED_BIT
),
349 EVENT_FILE_FL_RECORDED_CMD
= (1 << EVENT_FILE_FL_RECORDED_CMD_BIT
),
350 EVENT_FILE_FL_FILTERED
= (1 << EVENT_FILE_FL_FILTERED_BIT
),
351 EVENT_FILE_FL_NO_SET_FILTER
= (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT
),
352 EVENT_FILE_FL_SOFT_MODE
= (1 << EVENT_FILE_FL_SOFT_MODE_BIT
),
353 EVENT_FILE_FL_SOFT_DISABLED
= (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT
),
354 EVENT_FILE_FL_TRIGGER_MODE
= (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT
),
355 EVENT_FILE_FL_TRIGGER_COND
= (1 << EVENT_FILE_FL_TRIGGER_COND_BIT
),
356 EVENT_FILE_FL_PID_FILTER
= (1 << EVENT_FILE_FL_PID_FILTER_BIT
),
359 struct trace_event_file
{
360 struct list_head list
;
361 struct trace_event_call
*event_call
;
362 struct event_filter
*filter
;
364 struct trace_array
*tr
;
365 struct trace_subsystem_dir
*system
;
366 struct list_head triggers
;
371 * bit 1: enabled cmd record
372 * bit 2: enable/disable with the soft disable bit
373 * bit 3: soft disabled
374 * bit 4: trigger enabled
376 * Note: The bits must be set atomically to prevent races
377 * from other writers. Reads of flags do not need to be in
378 * sync as they occur in critical sections. But the way flags
379 * is currently used, these changes do not affect the code
380 * except that when a change is made, it may have a slight
381 * delay in propagating the changes to other CPUs due to
382 * caching and such. Which is mostly OK ;-)
385 atomic_t sm_ref
; /* soft-mode reference counter */
386 atomic_t tm_ref
; /* trigger-mode reference counter */
389 #define __TRACE_EVENT_FLAGS(name, value) \
390 static int __init trace_init_flags_##name(void) \
392 event_##name.flags |= value; \
395 early_initcall(trace_init_flags_##name);
397 #define __TRACE_EVENT_PERF_PERM(name, expr...) \
398 static int perf_perm_##name(struct trace_event_call *tp_event, \
399 struct perf_event *p_event) \
401 return ({ expr; }); \
403 static int __init trace_init_perf_perm_##name(void) \
405 event_##name.perf_perm = &perf_perm_##name; \
408 early_initcall(trace_init_perf_perm_##name);
410 #define PERF_MAX_TRACE_SIZE 2048
412 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
414 enum event_trigger_type
{
416 ETT_TRACE_ONOFF
= (1 << 0),
417 ETT_SNAPSHOT
= (1 << 1),
418 ETT_STACKTRACE
= (1 << 2),
419 ETT_EVENT_ENABLE
= (1 << 3),
422 extern int filter_match_preds(struct event_filter
*filter
, void *rec
);
424 extern int filter_check_discard(struct trace_event_file
*file
, void *rec
,
425 struct ring_buffer
*buffer
,
426 struct ring_buffer_event
*event
);
427 extern int call_filter_check_discard(struct trace_event_call
*call
, void *rec
,
428 struct ring_buffer
*buffer
,
429 struct ring_buffer_event
*event
);
430 extern enum event_trigger_type
event_triggers_call(struct trace_event_file
*file
,
432 extern void event_triggers_post_call(struct trace_event_file
*file
,
433 enum event_trigger_type tt
);
435 bool trace_event_ignore_this_pid(struct trace_event_file
*trace_file
);
438 * trace_trigger_soft_disabled - do triggers and test if soft disabled
439 * @file: The file pointer of the event to test
441 * If any triggers without filters are attached to this event, they
442 * will be called here. If the event is soft disabled and has no
443 * triggers that require testing the fields, it will return true,
447 trace_trigger_soft_disabled(struct trace_event_file
*file
)
449 unsigned long eflags
= file
->flags
;
451 if (!(eflags
& EVENT_FILE_FL_TRIGGER_COND
)) {
452 if (eflags
& EVENT_FILE_FL_TRIGGER_MODE
)
453 event_triggers_call(file
, NULL
);
454 if (eflags
& EVENT_FILE_FL_SOFT_DISABLED
)
456 if (eflags
& EVENT_FILE_FL_PID_FILTER
)
457 return trace_event_ignore_this_pid(file
);
463 * Helper function for event_trigger_unlock_commit{_regs}().
464 * If there are event triggers attached to this event that requires
465 * filtering against its fields, then they wil be called as the
466 * entry already holds the field information of the current event.
468 * It also checks if the event should be discarded or not.
469 * It is to be discarded if the event is soft disabled and the
470 * event was only recorded to process triggers, or if the event
471 * filter is active and this event did not match the filters.
473 * Returns true if the event is discarded, false otherwise.
476 __event_trigger_test_discard(struct trace_event_file
*file
,
477 struct ring_buffer
*buffer
,
478 struct ring_buffer_event
*event
,
480 enum event_trigger_type
*tt
)
482 unsigned long eflags
= file
->flags
;
484 if (eflags
& EVENT_FILE_FL_TRIGGER_COND
)
485 *tt
= event_triggers_call(file
, entry
);
487 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT
, &file
->flags
))
488 ring_buffer_discard_commit(buffer
, event
);
489 else if (!filter_check_discard(file
, entry
, buffer
, event
))
496 * event_trigger_unlock_commit - handle triggers and finish event commit
497 * @file: The file pointer assoctiated to the event
498 * @buffer: The ring buffer that the event is being written to
499 * @event: The event meta data in the ring buffer
500 * @entry: The event itself
501 * @irq_flags: The state of the interrupts at the start of the event
502 * @pc: The state of the preempt count at the start of the event.
504 * This is a helper function to handle triggers that require data
505 * from the event itself. It also tests the event against filters and
506 * if the event is soft disabled and should be discarded.
509 event_trigger_unlock_commit(struct trace_event_file
*file
,
510 struct ring_buffer
*buffer
,
511 struct ring_buffer_event
*event
,
512 void *entry
, unsigned long irq_flags
, int pc
)
514 enum event_trigger_type tt
= ETT_NONE
;
516 if (!__event_trigger_test_discard(file
, buffer
, event
, entry
, &tt
))
517 trace_buffer_unlock_commit(file
->tr
, buffer
, event
, irq_flags
, pc
);
520 event_triggers_post_call(file
, tt
);
524 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
525 * @file: The file pointer assoctiated to the event
526 * @buffer: The ring buffer that the event is being written to
527 * @event: The event meta data in the ring buffer
528 * @entry: The event itself
529 * @irq_flags: The state of the interrupts at the start of the event
530 * @pc: The state of the preempt count at the start of the event.
532 * This is a helper function to handle triggers that require data
533 * from the event itself. It also tests the event against filters and
534 * if the event is soft disabled and should be discarded.
536 * Same as event_trigger_unlock_commit() but calls
537 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
540 event_trigger_unlock_commit_regs(struct trace_event_file
*file
,
541 struct ring_buffer
*buffer
,
542 struct ring_buffer_event
*event
,
543 void *entry
, unsigned long irq_flags
, int pc
,
544 struct pt_regs
*regs
)
546 enum event_trigger_type tt
= ETT_NONE
;
548 if (!__event_trigger_test_discard(file
, buffer
, event
, entry
, &tt
))
549 trace_buffer_unlock_commit_regs(file
->tr
, buffer
, event
,
550 irq_flags
, pc
, regs
);
553 event_triggers_post_call(file
, tt
);
556 #ifdef CONFIG_BPF_EVENTS
557 unsigned int trace_call_bpf(struct bpf_prog
*prog
, void *ctx
);
559 static inline unsigned int trace_call_bpf(struct bpf_prog
*prog
, void *ctx
)
567 FILTER_STATIC_STRING
,
573 extern int trace_event_raw_init(struct trace_event_call
*call
);
574 extern int trace_define_field(struct trace_event_call
*call
, const char *type
,
575 const char *name
, int offset
, int size
,
576 int is_signed
, int filter_type
);
577 extern int trace_add_event_call(struct trace_event_call
*call
);
578 extern int trace_remove_event_call(struct trace_event_call
*call
);
580 #define is_signed_type(type) (((type)(-1)) < (type)1)
582 int trace_set_clr_event(const char *system
, const char *event
, int set
);
585 * The double __builtin_constant_p is because gcc will give us an error
586 * if we try to allocate the static variable to fmt if it is not a
587 * constant. Even with the outer if statement optimizing out.
589 #define event_trace_printk(ip, fmt, args...) \
591 __trace_printk_check_format(fmt, ##args); \
592 tracing_record_cmdline(current); \
593 if (__builtin_constant_p(fmt)) { \
594 static const char *trace_printk_fmt \
595 __attribute__((section("__trace_printk_fmt"))) = \
596 __builtin_constant_p(fmt) ? fmt : NULL; \
598 __trace_bprintk(ip, trace_printk_fmt, ##args); \
600 __trace_printk(ip, fmt, ##args); \
603 #ifdef CONFIG_PERF_EVENTS
606 DECLARE_PER_CPU(struct pt_regs
, perf_trace_regs
);
608 extern int perf_trace_init(struct perf_event
*event
);
609 extern void perf_trace_destroy(struct perf_event
*event
);
610 extern int perf_trace_add(struct perf_event
*event
, int flags
);
611 extern void perf_trace_del(struct perf_event
*event
, int flags
);
612 extern int ftrace_profile_set_filter(struct perf_event
*event
, int event_id
,
614 extern void ftrace_profile_free_filter(struct perf_event
*event
);
615 extern void *perf_trace_buf_prepare(int size
, unsigned short type
,
616 struct pt_regs
**regs
, int *rctxp
);
619 perf_trace_buf_submit(void *raw_data
, int size
, int rctx
, u64 addr
,
620 u64 count
, struct pt_regs
*regs
, void *head
,
621 struct task_struct
*task
)
623 perf_tp_event(addr
, count
, raw_data
, size
, regs
, head
, rctx
, task
);
627 #endif /* _LINUX_TRACE_EVENT_H */