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 const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
20 const struct trace_print_flags *flag_array);
22 const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
23 const struct trace_print_flags *symbol_array);
25 #if BITS_PER_LONG == 32
26 const char *trace_print_symbols_seq_u64(struct trace_seq *p,
27 unsigned long long val,
28 const struct trace_print_flags_u64
32 const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
33 unsigned int bitmask_size);
35 const char *trace_print_hex_seq(struct trace_seq *p,
36 const unsigned char *buf, int len);
38 const char *trace_print_array_seq(struct trace_seq *p,
39 const void *buf, int count,
42 struct trace_iterator;
45 int trace_raw_output_prep(struct trace_iterator *iter,
46 struct trace_event *event);
49 * The trace entry - the most basic unit of tracing. This is what
50 * is printed in the end as a single line in the trace output, such as:
52 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
57 unsigned char preempt_count;
61 #define TRACE_EVENT_TYPE_MAX \
62 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
65 * Trace iterator - used by printout routines who present trace
66 * results to users and which routines might sleep, etc:
68 struct trace_iterator {
69 struct trace_array *tr;
71 struct trace_buffer *trace_buffer;
75 struct ring_buffer_iter **buffer_iter;
76 unsigned long iter_flags;
78 /* trace_seq for __print_flags() and __print_symbolic() etc. */
79 struct trace_seq tmp_seq;
81 cpumask_var_t started;
83 /* it's true when current open file is snapshot */
86 /* The below is zeroed out in pipe_read */
88 struct trace_entry *ent;
89 unsigned long lost_events;
98 /* All new field here will be zeroed out in pipe_read */
101 enum trace_iter_flags {
102 TRACE_FILE_LAT_FMT = 1,
103 TRACE_FILE_ANNOTATE = 2,
104 TRACE_FILE_TIME_IN_NS = 4,
108 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
109 int flags, struct trace_event *event);
111 struct trace_event_functions {
112 trace_print_func trace;
113 trace_print_func raw;
114 trace_print_func hex;
115 trace_print_func binary;
119 struct hlist_node node;
120 struct list_head list;
122 struct trace_event_functions *funcs;
125 extern int register_trace_event(struct trace_event *event);
126 extern int unregister_trace_event(struct trace_event *event);
128 /* Return values for print_line callback */
130 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
131 TRACE_TYPE_HANDLED = 1,
132 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
133 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
137 * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
138 * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
139 * simplifies those functions and keeps them in sync.
141 static inline enum print_line_t trace_handle_return(struct trace_seq *s)
143 return trace_seq_has_overflowed(s) ?
144 TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
147 void tracing_generic_entry_update(struct trace_entry *entry,
150 struct trace_event_file;
152 struct ring_buffer_event *
153 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
154 struct trace_event_file *trace_file,
155 int type, unsigned long len,
156 unsigned long flags, int pc);
157 struct ring_buffer_event *
158 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
159 int type, unsigned long len,
160 unsigned long flags, int pc);
161 void trace_buffer_unlock_commit(struct trace_array *tr,
162 struct ring_buffer *buffer,
163 struct ring_buffer_event *event,
164 unsigned long flags, int pc);
165 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
166 struct ring_buffer *buffer,
167 struct ring_buffer_event *event,
168 unsigned long flags, int pc,
169 struct pt_regs *regs);
170 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
171 struct ring_buffer_event *event);
173 void tracing_record_cmdline(struct task_struct *tsk);
175 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...);
181 TRACE_REG_UNREGISTER,
182 #ifdef CONFIG_PERF_EVENTS
183 TRACE_REG_PERF_REGISTER,
184 TRACE_REG_PERF_UNREGISTER,
186 TRACE_REG_PERF_CLOSE,
192 struct trace_event_call;
194 struct trace_event_class {
197 #ifdef CONFIG_PERF_EVENTS
200 int (*reg)(struct trace_event_call *event,
201 enum trace_reg type, void *data);
202 int (*define_fields)(struct trace_event_call *);
203 struct list_head *(*get_fields)(struct trace_event_call *);
204 struct list_head fields;
205 int (*raw_init)(struct trace_event_call *);
208 extern int trace_event_reg(struct trace_event_call *event,
209 enum trace_reg type, void *data);
211 struct trace_event_buffer {
212 struct ring_buffer *buffer;
213 struct ring_buffer_event *event;
214 struct trace_event_file *trace_file;
220 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
221 struct trace_event_file *trace_file,
224 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
227 TRACE_EVENT_FL_FILTERED_BIT,
228 TRACE_EVENT_FL_CAP_ANY_BIT,
229 TRACE_EVENT_FL_NO_SET_FILTER_BIT,
230 TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
231 TRACE_EVENT_FL_WAS_ENABLED_BIT,
232 TRACE_EVENT_FL_USE_CALL_FILTER_BIT,
233 TRACE_EVENT_FL_TRACEPOINT_BIT,
234 TRACE_EVENT_FL_KPROBE_BIT,
235 TRACE_EVENT_FL_UPROBE_BIT,
240 * FILTERED - The event has a filter attached
241 * CAP_ANY - Any user can enable for perf
242 * NO_SET_FILTER - Set when filter has error and is to be ignored
243 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
244 * WAS_ENABLED - Set and stays set when an event was ever enabled
245 * (used for module unloading, if a module event is enabled,
246 * it is best to clear the buffers that used it).
247 * USE_CALL_FILTER - For trace internal events, don't use file filter
248 * TRACEPOINT - Event is a tracepoint
249 * KPROBE - Event is a kprobe
250 * UPROBE - Event is a uprobe
253 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
254 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
255 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
256 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
257 TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
258 TRACE_EVENT_FL_USE_CALL_FILTER = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT),
259 TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
260 TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
261 TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
264 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
266 struct trace_event_call {
267 struct list_head list;
268 struct trace_event_class *class;
271 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
272 struct tracepoint *tp;
274 struct trace_event event;
276 struct event_filter *filter;
280 * bit 0: filter_active
281 * bit 1: allow trace by non root (cap any)
282 * bit 2: failed to apply filter
283 * bit 3: trace internal event (do not enable)
284 * bit 4: Event was enabled by module
285 * bit 5: use call filter rather than file filter
286 * bit 6: Event is a tracepoint
288 int flags; /* static flags of different events */
290 #ifdef CONFIG_PERF_EVENTS
292 struct hlist_head __percpu *perf_events;
293 struct bpf_prog *prog;
295 int (*perf_perm)(struct trace_event_call *,
296 struct perf_event *);
300 static inline const char *
301 trace_event_name(struct trace_event_call *call)
303 if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
304 return call->tp ? call->tp->name : NULL;
310 struct trace_subsystem_dir;
313 EVENT_FILE_FL_ENABLED_BIT,
314 EVENT_FILE_FL_RECORDED_CMD_BIT,
315 EVENT_FILE_FL_FILTERED_BIT,
316 EVENT_FILE_FL_NO_SET_FILTER_BIT,
317 EVENT_FILE_FL_SOFT_MODE_BIT,
318 EVENT_FILE_FL_SOFT_DISABLED_BIT,
319 EVENT_FILE_FL_TRIGGER_MODE_BIT,
320 EVENT_FILE_FL_TRIGGER_COND_BIT,
321 EVENT_FILE_FL_PID_FILTER_BIT,
326 * ENABLED - The event is enabled
327 * RECORDED_CMD - The comms should be recorded at sched_switch
328 * FILTERED - The event has a filter attached
329 * NO_SET_FILTER - Set when filter has error and is to be ignored
330 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
331 * SOFT_DISABLED - When set, do not trace the event (even though its
332 * tracepoint may be enabled)
333 * TRIGGER_MODE - When set, invoke the triggers associated with the event
334 * TRIGGER_COND - When set, one or more triggers has an associated filter
335 * PID_FILTER - When set, the event is filtered based on pid
338 EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT),
339 EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
340 EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT),
341 EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
342 EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT),
343 EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
344 EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
345 EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
346 EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
349 struct trace_event_file {
350 struct list_head list;
351 struct trace_event_call *event_call;
352 struct event_filter *filter;
354 struct trace_array *tr;
355 struct trace_subsystem_dir *system;
356 struct list_head triggers;
361 * bit 1: enabled cmd record
362 * bit 2: enable/disable with the soft disable bit
363 * bit 3: soft disabled
364 * bit 4: trigger enabled
366 * Note: The bits must be set atomically to prevent races
367 * from other writers. Reads of flags do not need to be in
368 * sync as they occur in critical sections. But the way flags
369 * is currently used, these changes do not affect the code
370 * except that when a change is made, it may have a slight
371 * delay in propagating the changes to other CPUs due to
372 * caching and such. Which is mostly OK ;-)
375 atomic_t sm_ref; /* soft-mode reference counter */
376 atomic_t tm_ref; /* trigger-mode reference counter */
379 #define __TRACE_EVENT_FLAGS(name, value) \
380 static int __init trace_init_flags_##name(void) \
382 event_##name.flags |= value; \
385 early_initcall(trace_init_flags_##name);
387 #define __TRACE_EVENT_PERF_PERM(name, expr...) \
388 static int perf_perm_##name(struct trace_event_call *tp_event, \
389 struct perf_event *p_event) \
391 return ({ expr; }); \
393 static int __init trace_init_perf_perm_##name(void) \
395 event_##name.perf_perm = &perf_perm_##name; \
398 early_initcall(trace_init_perf_perm_##name);
400 #define PERF_MAX_TRACE_SIZE 2048
402 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
404 enum event_trigger_type {
406 ETT_TRACE_ONOFF = (1 << 0),
407 ETT_SNAPSHOT = (1 << 1),
408 ETT_STACKTRACE = (1 << 2),
409 ETT_EVENT_ENABLE = (1 << 3),
412 extern int filter_match_preds(struct event_filter *filter, void *rec);
414 extern int filter_check_discard(struct trace_event_file *file, void *rec,
415 struct ring_buffer *buffer,
416 struct ring_buffer_event *event);
417 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
418 struct ring_buffer *buffer,
419 struct ring_buffer_event *event);
420 extern enum event_trigger_type event_triggers_call(struct trace_event_file *file,
422 extern void event_triggers_post_call(struct trace_event_file *file,
423 enum event_trigger_type tt,
426 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
429 * trace_trigger_soft_disabled - do triggers and test if soft disabled
430 * @file: The file pointer of the event to test
432 * If any triggers without filters are attached to this event, they
433 * will be called here. If the event is soft disabled and has no
434 * triggers that require testing the fields, it will return true,
438 trace_trigger_soft_disabled(struct trace_event_file *file)
440 unsigned long eflags = file->flags;
442 if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
443 if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
444 event_triggers_call(file, NULL);
445 if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
447 if (eflags & EVENT_FILE_FL_PID_FILTER)
448 return trace_event_ignore_this_pid(file);
454 * Helper function for event_trigger_unlock_commit{_regs}().
455 * If there are event triggers attached to this event that requires
456 * filtering against its fields, then they wil be called as the
457 * entry already holds the field information of the current event.
459 * It also checks if the event should be discarded or not.
460 * It is to be discarded if the event is soft disabled and the
461 * event was only recorded to process triggers, or if the event
462 * filter is active and this event did not match the filters.
464 * Returns true if the event is discarded, false otherwise.
467 __event_trigger_test_discard(struct trace_event_file *file,
468 struct ring_buffer *buffer,
469 struct ring_buffer_event *event,
471 enum event_trigger_type *tt)
473 unsigned long eflags = file->flags;
475 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
476 *tt = event_triggers_call(file, entry);
478 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags))
479 ring_buffer_discard_commit(buffer, event);
480 else if (!filter_check_discard(file, entry, buffer, event))
487 * event_trigger_unlock_commit - handle triggers and finish event commit
488 * @file: The file pointer assoctiated to the event
489 * @buffer: The ring buffer that the event is being written to
490 * @event: The event meta data in the ring buffer
491 * @entry: The event itself
492 * @irq_flags: The state of the interrupts at the start of the event
493 * @pc: The state of the preempt count at the start of the event.
495 * This is a helper function to handle triggers that require data
496 * from the event itself. It also tests the event against filters and
497 * if the event is soft disabled and should be discarded.
500 event_trigger_unlock_commit(struct trace_event_file *file,
501 struct ring_buffer *buffer,
502 struct ring_buffer_event *event,
503 void *entry, unsigned long irq_flags, int pc)
505 enum event_trigger_type tt = ETT_NONE;
507 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
508 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
511 event_triggers_post_call(file, tt, entry);
515 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
516 * @file: The file pointer assoctiated to the event
517 * @buffer: The ring buffer that the event is being written to
518 * @event: The event meta data in the ring buffer
519 * @entry: The event itself
520 * @irq_flags: The state of the interrupts at the start of the event
521 * @pc: The state of the preempt count at the start of the event.
523 * This is a helper function to handle triggers that require data
524 * from the event itself. It also tests the event against filters and
525 * if the event is soft disabled and should be discarded.
527 * Same as event_trigger_unlock_commit() but calls
528 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
531 event_trigger_unlock_commit_regs(struct trace_event_file *file,
532 struct ring_buffer *buffer,
533 struct ring_buffer_event *event,
534 void *entry, unsigned long irq_flags, int pc,
535 struct pt_regs *regs)
537 enum event_trigger_type tt = ETT_NONE;
539 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
540 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
541 irq_flags, pc, regs);
544 event_triggers_post_call(file, tt, entry);
547 #ifdef CONFIG_BPF_EVENTS
548 unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx);
550 static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx)
558 FILTER_STATIC_STRING,
566 extern int trace_event_raw_init(struct trace_event_call *call);
567 extern int trace_define_field(struct trace_event_call *call, const char *type,
568 const char *name, int offset, int size,
569 int is_signed, int filter_type);
570 extern int trace_add_event_call(struct trace_event_call *call);
571 extern int trace_remove_event_call(struct trace_event_call *call);
573 #define is_signed_type(type) (((type)(-1)) < (type)1)
575 int trace_set_clr_event(const char *system, const char *event, int set);
578 * The double __builtin_constant_p is because gcc will give us an error
579 * if we try to allocate the static variable to fmt if it is not a
580 * constant. Even with the outer if statement optimizing out.
582 #define event_trace_printk(ip, fmt, args...) \
584 __trace_printk_check_format(fmt, ##args); \
585 tracing_record_cmdline(current); \
586 if (__builtin_constant_p(fmt)) { \
587 static const char *trace_printk_fmt \
588 __attribute__((section("__trace_printk_fmt"))) = \
589 __builtin_constant_p(fmt) ? fmt : NULL; \
591 __trace_bprintk(ip, trace_printk_fmt, ##args); \
593 __trace_printk(ip, fmt, ##args); \
596 #ifdef CONFIG_PERF_EVENTS
599 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
601 extern int perf_trace_init(struct perf_event *event);
602 extern void perf_trace_destroy(struct perf_event *event);
603 extern int perf_trace_add(struct perf_event *event, int flags);
604 extern void perf_trace_del(struct perf_event *event, int flags);
605 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
607 extern void ftrace_profile_free_filter(struct perf_event *event);
608 extern void *perf_trace_buf_prepare(int size, unsigned short type,
609 struct pt_regs **regs, int *rctxp);
612 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
613 u64 count, struct pt_regs *regs, void *head,
614 struct task_struct *task)
616 perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
620 #endif /* _LINUX_TRACE_EVENT_H */