xref: /linux/include/linux/trace_events.h (revision 09670b8c38b37bc2d6fc5d01fa7e02c38f7adf36)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef _LINUX_TRACE_EVENT_H
4 #define _LINUX_TRACE_EVENT_H
5 
6 #include <linux/ring_buffer.h>
7 #include <linux/trace_seq.h>
8 #include <linux/percpu.h>
9 #include <linux/hardirq.h>
10 #include <linux/perf_event.h>
11 #include <linux/tracepoint.h>
12 
13 struct trace_array;
14 struct array_buffer;
15 struct tracer;
16 struct dentry;
17 struct bpf_prog;
18 union bpf_attr;
19 
20 /* Used for event string fields when they are NULL */
21 #define EVENT_NULL_STR		"(null)"
22 
23 const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
24 				  unsigned long flags,
25 				  const struct trace_print_flags *flag_array);
26 
27 const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
28 				    const struct trace_print_flags *symbol_array);
29 
30 #if BITS_PER_LONG == 32
31 const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
32 		      unsigned long long flags,
33 		      const struct trace_print_flags_u64 *flag_array);
34 
35 const char *trace_print_symbols_seq_u64(struct trace_seq *p,
36 					unsigned long long val,
37 					const struct trace_print_flags_u64
38 								 *symbol_array);
39 #endif
40 
41 const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
42 				    unsigned int bitmask_size);
43 
44 const char *trace_print_hex_seq(struct trace_seq *p,
45 				const unsigned char *buf, int len,
46 				bool concatenate);
47 
48 const char *trace_print_array_seq(struct trace_seq *p,
49 				   const void *buf, int count,
50 				   size_t el_size);
51 
52 const char *
53 trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
54 			 int prefix_type, int rowsize, int groupsize,
55 			 const void *buf, size_t len, bool ascii);
56 
57 struct trace_iterator;
58 struct trace_event;
59 
60 int trace_raw_output_prep(struct trace_iterator *iter,
61 			  struct trace_event *event);
62 extern __printf(2, 3)
63 void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...);
64 
65 /* Used to find the offset and length of dynamic fields in trace events */
66 struct trace_dynamic_info {
67 #ifdef CONFIG_CPU_BIG_ENDIAN
68 	u16	len;
69 	u16	offset;
70 #else
71 	u16	offset;
72 	u16	len;
73 #endif
74 } __packed;
75 
76 /*
77  * The trace entry - the most basic unit of tracing. This is what
78  * is printed in the end as a single line in the trace output, such as:
79  *
80  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
81  */
82 struct trace_entry {
83 	unsigned short		type;
84 	unsigned char		flags;
85 	unsigned char		preempt_count;
86 	int			pid;
87 };
88 
89 #define TRACE_EVENT_TYPE_MAX						\
90 	((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
91 
92 /*
93  * Trace iterator - used by printout routines who present trace
94  * results to users and which routines might sleep, etc:
95  */
96 struct trace_iterator {
97 	struct trace_array	*tr;
98 	struct tracer		*trace;
99 	struct array_buffer	*array_buffer;
100 	void			*private;
101 	int			cpu_file;
102 	struct mutex		mutex;
103 	struct ring_buffer_iter	**buffer_iter;
104 	unsigned long		iter_flags;
105 	void			*temp;	/* temp holder */
106 	unsigned int		temp_size;
107 	char			*fmt;	/* modified format holder */
108 	unsigned int		fmt_size;
109 	atomic_t		wait_index;
110 
111 	/* trace_seq for __print_flags() and __print_symbolic() etc. */
112 	struct trace_seq	tmp_seq;
113 
114 	cpumask_var_t		started;
115 
116 	/* Set when the file is closed to prevent new waiters */
117 	bool			closed;
118 
119 	/* it's true when current open file is snapshot */
120 	bool			snapshot;
121 
122 	/* The below is zeroed out in pipe_read */
123 	struct trace_seq	seq;
124 	struct trace_entry	*ent;
125 	unsigned long		lost_events;
126 	int			leftover;
127 	int			ent_size;
128 	int			cpu;
129 	u64			ts;
130 
131 	loff_t			pos;
132 	long			idx;
133 
134 	/* All new field here will be zeroed out in pipe_read */
135 };
136 
137 enum trace_iter_flags {
138 	TRACE_FILE_LAT_FMT	= 1,
139 	TRACE_FILE_ANNOTATE	= 2,
140 	TRACE_FILE_TIME_IN_NS	= 4,
141 	TRACE_FILE_PAUSE	= 8,
142 };
143 
144 
145 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
146 				      int flags, struct trace_event *event);
147 
148 struct trace_event_functions {
149 	trace_print_func	trace;
150 	trace_print_func	raw;
151 	trace_print_func	hex;
152 	trace_print_func	binary;
153 };
154 
155 struct trace_event {
156 	struct hlist_node		node;
157 	int				type;
158 	struct trace_event_functions	*funcs;
159 };
160 
161 extern int register_trace_event(struct trace_event *event);
162 extern int unregister_trace_event(struct trace_event *event);
163 
164 /* Return values for print_line callback */
165 enum print_line_t {
166 	TRACE_TYPE_PARTIAL_LINE	= 0,	/* Retry after flushing the seq */
167 	TRACE_TYPE_HANDLED	= 1,
168 	TRACE_TYPE_UNHANDLED	= 2,	/* Relay to other output functions */
169 	TRACE_TYPE_NO_CONSUME	= 3	/* Handled but ask to not consume */
170 };
171 
172 enum print_line_t trace_handle_return(struct trace_seq *s);
173 
tracing_generic_entry_update(struct trace_entry * entry,unsigned short type,unsigned int trace_ctx)174 static inline void tracing_generic_entry_update(struct trace_entry *entry,
175 						unsigned short type,
176 						unsigned int trace_ctx)
177 {
178 	entry->preempt_count		= trace_ctx & 0xff;
179 	entry->pid			= current->pid;
180 	entry->type			= type;
181 	entry->flags =			trace_ctx >> 16;
182 }
183 
184 unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
185 
186 enum trace_flag_type {
187 	TRACE_FLAG_IRQS_OFF		= 0x01,
188 	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x02,
189 	TRACE_FLAG_NEED_RESCHED		= 0x04,
190 	TRACE_FLAG_HARDIRQ		= 0x08,
191 	TRACE_FLAG_SOFTIRQ		= 0x10,
192 	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
193 	TRACE_FLAG_NMI			= 0x40,
194 	TRACE_FLAG_BH_OFF		= 0x80,
195 };
196 
tracing_gen_ctx_flags(unsigned long irqflags)197 static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
198 {
199 	unsigned int irq_status = irqs_disabled_flags(irqflags) ?
200 		TRACE_FLAG_IRQS_OFF : 0;
201 	return tracing_gen_ctx_irq_test(irq_status);
202 }
tracing_gen_ctx(void)203 static inline unsigned int tracing_gen_ctx(void)
204 {
205 	unsigned long irqflags;
206 
207 	local_save_flags(irqflags);
208 	return tracing_gen_ctx_flags(irqflags);
209 }
210 
tracing_gen_ctx_dec(void)211 static inline unsigned int tracing_gen_ctx_dec(void)
212 {
213 	unsigned int trace_ctx;
214 
215 	trace_ctx = tracing_gen_ctx();
216 	/*
217 	 * Subtract one from the preemption counter if preemption is enabled,
218 	 * see trace_event_buffer_reserve()for details.
219 	 */
220 	if (IS_ENABLED(CONFIG_PREEMPTION))
221 		trace_ctx--;
222 	return trace_ctx;
223 }
224 
225 struct trace_event_file;
226 
227 struct ring_buffer_event *
228 trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
229 				struct trace_event_file *trace_file,
230 				int type, unsigned long len,
231 				unsigned int trace_ctx);
232 
233 #define TRACE_RECORD_CMDLINE	BIT(0)
234 #define TRACE_RECORD_TGID	BIT(1)
235 
236 void tracing_record_taskinfo(struct task_struct *task, int flags);
237 void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
238 					  struct task_struct *next, int flags);
239 
240 void tracing_record_cmdline(struct task_struct *task);
241 void tracing_record_tgid(struct task_struct *task);
242 
243 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
244 	 __printf(3, 4);
245 
246 struct event_filter;
247 
248 enum trace_reg {
249 	TRACE_REG_REGISTER,
250 	TRACE_REG_UNREGISTER,
251 #ifdef CONFIG_PERF_EVENTS
252 	TRACE_REG_PERF_REGISTER,
253 	TRACE_REG_PERF_UNREGISTER,
254 	TRACE_REG_PERF_OPEN,
255 	TRACE_REG_PERF_CLOSE,
256 	/*
257 	 * These (ADD/DEL) use a 'boolean' return value, where 1 (true) means a
258 	 * custom action was taken and the default action is not to be
259 	 * performed.
260 	 */
261 	TRACE_REG_PERF_ADD,
262 	TRACE_REG_PERF_DEL,
263 #endif
264 };
265 
266 struct trace_event_call;
267 
268 #define TRACE_FUNCTION_TYPE ((const char *)~0UL)
269 
270 struct trace_event_fields {
271 	const char *type;
272 	union {
273 		struct {
274 			const char *name;
275 			const int  size;
276 			const int  align;
277 			const unsigned int is_signed:1;
278 			unsigned int needs_test:1;
279 			const int  filter_type;
280 			const int  len;
281 		};
282 		int (*define_fields)(struct trace_event_call *);
283 	};
284 };
285 
286 struct trace_event_class {
287 	const char		*system;
288 	void			*probe;
289 #ifdef CONFIG_PERF_EVENTS
290 	void			*perf_probe;
291 #endif
292 	int			(*reg)(struct trace_event_call *event,
293 				       enum trace_reg type, void *data);
294 	struct trace_event_fields *fields_array;
295 	struct list_head	*(*get_fields)(struct trace_event_call *);
296 	struct list_head	fields;
297 	int			(*raw_init)(struct trace_event_call *);
298 };
299 
300 extern int trace_event_reg(struct trace_event_call *event,
301 			    enum trace_reg type, void *data);
302 
303 struct trace_event_buffer {
304 	struct trace_buffer		*buffer;
305 	struct ring_buffer_event	*event;
306 	struct trace_event_file		*trace_file;
307 	void				*entry;
308 	unsigned int			trace_ctx;
309 	struct pt_regs			*regs;
310 };
311 
312 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
313 				  struct trace_event_file *trace_file,
314 				  unsigned long len);
315 
316 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
317 
318 enum {
319 	TRACE_EVENT_FL_CAP_ANY_BIT,
320 	TRACE_EVENT_FL_NO_SET_FILTER_BIT,
321 	TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
322 	TRACE_EVENT_FL_TRACEPOINT_BIT,
323 	TRACE_EVENT_FL_DYNAMIC_BIT,
324 	TRACE_EVENT_FL_KPROBE_BIT,
325 	TRACE_EVENT_FL_UPROBE_BIT,
326 	TRACE_EVENT_FL_EPROBE_BIT,
327 	TRACE_EVENT_FL_FPROBE_BIT,
328 	TRACE_EVENT_FL_CUSTOM_BIT,
329 	TRACE_EVENT_FL_TEST_STR_BIT,
330 };
331 
332 /*
333  * Event flags:
334  *  CAP_ANY	  - Any user can enable for perf
335  *  NO_SET_FILTER - Set when filter has error and is to be ignored
336  *  IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
337  *  TRACEPOINT    - Event is a tracepoint
338  *  DYNAMIC       - Event is a dynamic event (created at run time)
339  *  KPROBE        - Event is a kprobe
340  *  UPROBE        - Event is a uprobe
341  *  EPROBE        - Event is an event probe
342  *  FPROBE        - Event is an function probe
343  *  CUSTOM        - Event is a custom event (to be attached to an exsiting tracepoint)
344  *                   This is set when the custom event has not been attached
345  *                   to a tracepoint yet, then it is cleared when it is.
346  *  TEST_STR      - The event has a "%s" that points to a string outside the event
347  */
348 enum {
349 	TRACE_EVENT_FL_CAP_ANY		= (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
350 	TRACE_EVENT_FL_NO_SET_FILTER	= (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
351 	TRACE_EVENT_FL_IGNORE_ENABLE	= (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
352 	TRACE_EVENT_FL_TRACEPOINT	= (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
353 	TRACE_EVENT_FL_DYNAMIC		= (1 << TRACE_EVENT_FL_DYNAMIC_BIT),
354 	TRACE_EVENT_FL_KPROBE		= (1 << TRACE_EVENT_FL_KPROBE_BIT),
355 	TRACE_EVENT_FL_UPROBE		= (1 << TRACE_EVENT_FL_UPROBE_BIT),
356 	TRACE_EVENT_FL_EPROBE		= (1 << TRACE_EVENT_FL_EPROBE_BIT),
357 	TRACE_EVENT_FL_FPROBE		= (1 << TRACE_EVENT_FL_FPROBE_BIT),
358 	TRACE_EVENT_FL_CUSTOM		= (1 << TRACE_EVENT_FL_CUSTOM_BIT),
359 	TRACE_EVENT_FL_TEST_STR		= (1 << TRACE_EVENT_FL_TEST_STR_BIT),
360 };
361 
362 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
363 
364 struct trace_event_call {
365 	struct list_head	list;
366 	struct trace_event_class *class;
367 	union {
368 		const char		*name;
369 		/* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
370 		struct tracepoint	*tp;
371 	};
372 	struct trace_event	event;
373 	char			*print_fmt;
374 	/*
375 	 * Static events can disappear with modules,
376 	 * where as dynamic ones need their own ref count.
377 	 */
378 	union {
379 		void				*module;
380 		atomic_t			refcnt;
381 	};
382 	void			*data;
383 
384 	/* See the TRACE_EVENT_FL_* flags above */
385 	int			flags; /* static flags of different events */
386 
387 #ifdef CONFIG_PERF_EVENTS
388 	int				perf_refcount;
389 	struct hlist_head __percpu	*perf_events;
390 	struct bpf_prog_array __rcu	*prog_array;
391 
392 	int	(*perf_perm)(struct trace_event_call *,
393 			     struct perf_event *);
394 #endif
395 };
396 
397 #ifdef CONFIG_DYNAMIC_EVENTS
398 bool trace_event_dyn_try_get_ref(struct trace_event_call *call);
399 void trace_event_dyn_put_ref(struct trace_event_call *call);
400 bool trace_event_dyn_busy(struct trace_event_call *call);
401 #else
trace_event_dyn_try_get_ref(struct trace_event_call * call)402 static inline bool trace_event_dyn_try_get_ref(struct trace_event_call *call)
403 {
404 	/* Without DYNAMIC_EVENTS configured, nothing should be calling this */
405 	return false;
406 }
trace_event_dyn_put_ref(struct trace_event_call * call)407 static inline void trace_event_dyn_put_ref(struct trace_event_call *call)
408 {
409 }
trace_event_dyn_busy(struct trace_event_call * call)410 static inline bool trace_event_dyn_busy(struct trace_event_call *call)
411 {
412 	/* Nothing should call this without DYNAIMIC_EVENTS configured. */
413 	return true;
414 }
415 #endif
416 
trace_event_try_get_ref(struct trace_event_call * call)417 static inline bool trace_event_try_get_ref(struct trace_event_call *call)
418 {
419 	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
420 		return trace_event_dyn_try_get_ref(call);
421 	else
422 		return try_module_get(call->module);
423 }
424 
trace_event_put_ref(struct trace_event_call * call)425 static inline void trace_event_put_ref(struct trace_event_call *call)
426 {
427 	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
428 		trace_event_dyn_put_ref(call);
429 	else
430 		module_put(call->module);
431 }
432 
433 #ifdef CONFIG_PERF_EVENTS
bpf_prog_array_valid(struct trace_event_call * call)434 static inline bool bpf_prog_array_valid(struct trace_event_call *call)
435 {
436 	/*
437 	 * This inline function checks whether call->prog_array
438 	 * is valid or not. The function is called in various places,
439 	 * outside rcu_read_lock/unlock, as a heuristic to speed up execution.
440 	 *
441 	 * If this function returns true, and later call->prog_array
442 	 * becomes false inside rcu_read_lock/unlock region,
443 	 * we bail out then. If this function return false,
444 	 * there is a risk that we might miss a few events if the checking
445 	 * were delayed until inside rcu_read_lock/unlock region and
446 	 * call->prog_array happened to become non-NULL then.
447 	 *
448 	 * Here, READ_ONCE() is used instead of rcu_access_pointer().
449 	 * rcu_access_pointer() requires the actual definition of
450 	 * "struct bpf_prog_array" while READ_ONCE() only needs
451 	 * a declaration of the same type.
452 	 */
453 	return !!READ_ONCE(call->prog_array);
454 }
455 #endif
456 
457 static inline const char *
trace_event_name(struct trace_event_call * call)458 trace_event_name(struct trace_event_call *call)
459 {
460 	if (call->flags & TRACE_EVENT_FL_CUSTOM)
461 		return call->name;
462 	else if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
463 		return call->tp ? call->tp->name : NULL;
464 	else
465 		return call->name;
466 }
467 
468 static inline struct list_head *
trace_get_fields(struct trace_event_call * event_call)469 trace_get_fields(struct trace_event_call *event_call)
470 {
471 	if (!event_call->class->get_fields)
472 		return &event_call->class->fields;
473 	return event_call->class->get_fields(event_call);
474 }
475 
476 struct trace_subsystem_dir;
477 
478 enum {
479 	EVENT_FILE_FL_ENABLED_BIT,
480 	EVENT_FILE_FL_RECORDED_CMD_BIT,
481 	EVENT_FILE_FL_RECORDED_TGID_BIT,
482 	EVENT_FILE_FL_FILTERED_BIT,
483 	EVENT_FILE_FL_NO_SET_FILTER_BIT,
484 	EVENT_FILE_FL_SOFT_DISABLED_BIT,
485 	EVENT_FILE_FL_TRIGGER_MODE_BIT,
486 	EVENT_FILE_FL_TRIGGER_COND_BIT,
487 	EVENT_FILE_FL_PID_FILTER_BIT,
488 	EVENT_FILE_FL_WAS_ENABLED_BIT,
489 	EVENT_FILE_FL_FREED_BIT,
490 };
491 
492 extern struct trace_event_file *trace_get_event_file(const char *instance,
493 						     const char *system,
494 						     const char *event);
495 extern void trace_put_event_file(struct trace_event_file *file);
496 
497 #define MAX_DYNEVENT_CMD_LEN	(2048)
498 
499 enum dynevent_type {
500 	DYNEVENT_TYPE_SYNTH = 1,
501 	DYNEVENT_TYPE_KPROBE,
502 	DYNEVENT_TYPE_NONE,
503 };
504 
505 struct dynevent_cmd;
506 
507 typedef int (*dynevent_create_fn_t)(struct dynevent_cmd *cmd);
508 
509 struct dynevent_cmd {
510 	struct seq_buf		seq;
511 	const char		*event_name;
512 	unsigned int		n_fields;
513 	enum dynevent_type	type;
514 	dynevent_create_fn_t	run_command;
515 	void			*private_data;
516 };
517 
518 extern int dynevent_create(struct dynevent_cmd *cmd);
519 
520 extern int synth_event_delete(const char *name);
521 
522 extern void synth_event_cmd_init(struct dynevent_cmd *cmd,
523 				 char *buf, int maxlen);
524 
525 extern int __synth_event_gen_cmd_start(struct dynevent_cmd *cmd,
526 				       const char *name,
527 				       struct module *mod, ...);
528 
529 #define synth_event_gen_cmd_start(cmd, name, mod, ...)	\
530 	__synth_event_gen_cmd_start(cmd, name, mod, ## __VA_ARGS__, NULL)
531 
532 struct synth_field_desc {
533 	const char *type;
534 	const char *name;
535 };
536 
537 extern int synth_event_gen_cmd_array_start(struct dynevent_cmd *cmd,
538 					   const char *name,
539 					   struct module *mod,
540 					   struct synth_field_desc *fields,
541 					   unsigned int n_fields);
542 extern int synth_event_create(const char *name,
543 			      struct synth_field_desc *fields,
544 			      unsigned int n_fields, struct module *mod);
545 
546 extern int synth_event_add_field(struct dynevent_cmd *cmd,
547 				 const char *type,
548 				 const char *name);
549 extern int synth_event_add_field_str(struct dynevent_cmd *cmd,
550 				     const char *type_name);
551 extern int synth_event_add_fields(struct dynevent_cmd *cmd,
552 				  struct synth_field_desc *fields,
553 				  unsigned int n_fields);
554 
555 #define synth_event_gen_cmd_end(cmd)	\
556 	dynevent_create(cmd)
557 
558 struct synth_event;
559 
560 struct synth_event_trace_state {
561 	struct trace_event_buffer fbuffer;
562 	struct synth_trace_event *entry;
563 	struct trace_buffer *buffer;
564 	struct synth_event *event;
565 	unsigned int cur_field;
566 	unsigned int n_u64;
567 	bool disabled;
568 	bool add_next;
569 	bool add_name;
570 };
571 
572 extern int synth_event_trace(struct trace_event_file *file,
573 			     unsigned int n_vals, ...);
574 extern int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
575 				   unsigned int n_vals);
576 extern int synth_event_trace_start(struct trace_event_file *file,
577 				   struct synth_event_trace_state *trace_state);
578 extern int synth_event_add_next_val(u64 val,
579 				    struct synth_event_trace_state *trace_state);
580 extern int synth_event_add_val(const char *field_name, u64 val,
581 			       struct synth_event_trace_state *trace_state);
582 extern int synth_event_trace_end(struct synth_event_trace_state *trace_state);
583 
584 extern int kprobe_event_delete(const char *name);
585 
586 extern void kprobe_event_cmd_init(struct dynevent_cmd *cmd,
587 				  char *buf, int maxlen);
588 
589 #define kprobe_event_gen_cmd_start(cmd, name, loc, ...)			\
590 	__kprobe_event_gen_cmd_start(cmd, false, name, loc, ## __VA_ARGS__, NULL)
591 
592 #define kretprobe_event_gen_cmd_start(cmd, name, loc, ...)		\
593 	__kprobe_event_gen_cmd_start(cmd, true, name, loc, ## __VA_ARGS__, NULL)
594 
595 extern int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd,
596 					bool kretprobe,
597 					const char *name,
598 					const char *loc, ...);
599 
600 #define kprobe_event_add_fields(cmd, ...)	\
601 	__kprobe_event_add_fields(cmd, ## __VA_ARGS__, NULL)
602 
603 #define kprobe_event_add_field(cmd, field)	\
604 	__kprobe_event_add_fields(cmd, field, NULL)
605 
606 extern int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...);
607 
608 #define kprobe_event_gen_cmd_end(cmd)		\
609 	dynevent_create(cmd)
610 
611 #define kretprobe_event_gen_cmd_end(cmd)	\
612 	dynevent_create(cmd)
613 
614 /*
615  * Event file flags:
616  *  ENABLED	  - The event is enabled
617  *  RECORDED_CMD  - The comms should be recorded at sched_switch
618  *  RECORDED_TGID - The tgids should be recorded at sched_switch
619  *  FILTERED	  - The event has a filter attached
620  *  NO_SET_FILTER - Set when filter has error and is to be ignored
621  *  SOFT_DISABLED - When set, do not trace the event (even though its
622  *                   tracepoint may be enabled)
623  *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
624  *  TRIGGER_COND  - When set, one or more triggers has an associated filter
625  *  PID_FILTER    - When set, the event is filtered based on pid
626  *  WAS_ENABLED   - Set when enabled to know to clear trace on module removal
627  *  FREED         - File descriptor is freed, all fields should be considered invalid
628  */
629 enum {
630 	EVENT_FILE_FL_ENABLED		= (1 << EVENT_FILE_FL_ENABLED_BIT),
631 	EVENT_FILE_FL_RECORDED_CMD	= (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
632 	EVENT_FILE_FL_RECORDED_TGID	= (1 << EVENT_FILE_FL_RECORDED_TGID_BIT),
633 	EVENT_FILE_FL_FILTERED		= (1 << EVENT_FILE_FL_FILTERED_BIT),
634 	EVENT_FILE_FL_NO_SET_FILTER	= (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
635 	EVENT_FILE_FL_SOFT_DISABLED	= (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
636 	EVENT_FILE_FL_TRIGGER_MODE	= (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
637 	EVENT_FILE_FL_TRIGGER_COND	= (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
638 	EVENT_FILE_FL_PID_FILTER	= (1 << EVENT_FILE_FL_PID_FILTER_BIT),
639 	EVENT_FILE_FL_WAS_ENABLED	= (1 << EVENT_FILE_FL_WAS_ENABLED_BIT),
640 	EVENT_FILE_FL_FREED		= (1 << EVENT_FILE_FL_FREED_BIT),
641 };
642 
643 struct trace_event_file {
644 	struct list_head		list;
645 	struct trace_event_call		*event_call;
646 	struct event_filter __rcu	*filter;
647 	struct eventfs_inode		*ei;
648 	struct trace_array		*tr;
649 	struct trace_subsystem_dir	*system;
650 	struct list_head		triggers;
651 
652 	/*
653 	 * 32 bit flags:
654 	 *   bit 0:		enabled
655 	 *   bit 1:		enabled cmd record
656 	 *   bit 2:		enable/disable with the soft disable bit
657 	 *   bit 3:		soft disabled
658 	 *   bit 4:		trigger enabled
659 	 *
660 	 * Note: The bits must be set atomically to prevent races
661 	 * from other writers. Reads of flags do not need to be in
662 	 * sync as they occur in critical sections. But the way flags
663 	 * is currently used, these changes do not affect the code
664 	 * except that when a change is made, it may have a slight
665 	 * delay in propagating the changes to other CPUs due to
666 	 * caching and such. Which is mostly OK ;-)
667 	 */
668 	unsigned long		flags;
669 	refcount_t		ref;	/* ref count for opened files */
670 	atomic_t		sm_ref;	/* soft-mode reference counter */
671 	atomic_t		tm_ref;	/* trigger-mode reference counter */
672 };
673 
674 #ifdef CONFIG_HIST_TRIGGERS
675 extern struct irq_work hist_poll_work;
676 extern wait_queue_head_t hist_poll_wq;
677 
hist_poll_wakeup(void)678 static inline void hist_poll_wakeup(void)
679 {
680 	if (wq_has_sleeper(&hist_poll_wq))
681 		irq_work_queue(&hist_poll_work);
682 }
683 
684 #define hist_poll_wait(file, wait)	\
685 	poll_wait(file, &hist_poll_wq, wait)
686 #endif
687 
688 #define __TRACE_EVENT_FLAGS(name, value)				\
689 	static int __init trace_init_flags_##name(void)			\
690 	{								\
691 		event_##name.flags |= value;				\
692 		return 0;						\
693 	}								\
694 	early_initcall(trace_init_flags_##name);
695 
696 #define __TRACE_EVENT_PERF_PERM(name, expr...)				\
697 	static int perf_perm_##name(struct trace_event_call *tp_event, \
698 				    struct perf_event *p_event)		\
699 	{								\
700 		return ({ expr; });					\
701 	}								\
702 	static int __init trace_init_perf_perm_##name(void)		\
703 	{								\
704 		event_##name.perf_perm = &perf_perm_##name;		\
705 		return 0;						\
706 	}								\
707 	early_initcall(trace_init_perf_perm_##name);
708 
709 #define PERF_MAX_TRACE_SIZE	8192
710 
711 #define MAX_FILTER_STR_VAL	256U	/* Should handle KSYM_SYMBOL_LEN */
712 
713 enum event_trigger_type {
714 	ETT_NONE		= (0),
715 	ETT_TRACE_ONOFF		= (1 << 0),
716 	ETT_SNAPSHOT		= (1 << 1),
717 	ETT_STACKTRACE		= (1 << 2),
718 	ETT_EVENT_ENABLE	= (1 << 3),
719 	ETT_EVENT_HIST		= (1 << 4),
720 	ETT_HIST_ENABLE		= (1 << 5),
721 	ETT_EVENT_EPROBE	= (1 << 6),
722 };
723 
724 extern int filter_match_preds(struct event_filter *filter, void *rec);
725 
726 extern enum event_trigger_type
727 event_triggers_call(struct trace_event_file *file,
728 		    struct trace_buffer *buffer, void *rec,
729 		    struct ring_buffer_event *event);
730 extern void
731 event_triggers_post_call(struct trace_event_file *file,
732 			 enum event_trigger_type tt);
733 
734 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
735 
736 bool __trace_trigger_soft_disabled(struct trace_event_file *file);
737 
738 /**
739  * trace_trigger_soft_disabled - do triggers and test if soft disabled
740  * @file: The file pointer of the event to test
741  *
742  * If any triggers without filters are attached to this event, they
743  * will be called here. If the event is soft disabled and has no
744  * triggers that require testing the fields, it will return true,
745  * otherwise false.
746  */
747 static __always_inline bool
trace_trigger_soft_disabled(struct trace_event_file * file)748 trace_trigger_soft_disabled(struct trace_event_file *file)
749 {
750 	unsigned long eflags = file->flags;
751 
752 	if (likely(!(eflags & (EVENT_FILE_FL_TRIGGER_MODE |
753 			       EVENT_FILE_FL_SOFT_DISABLED |
754 			       EVENT_FILE_FL_PID_FILTER))))
755 		return false;
756 
757 	if (likely(eflags & EVENT_FILE_FL_TRIGGER_COND))
758 		return false;
759 
760 	return __trace_trigger_soft_disabled(file);
761 }
762 
763 #ifdef CONFIG_BPF_EVENTS
764 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx);
765 int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
766 void perf_event_detach_bpf_prog(struct perf_event *event);
767 int perf_event_query_prog_array(struct perf_event *event, void __user *info);
768 
769 struct bpf_raw_tp_link;
770 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
771 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
772 
773 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name);
774 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp);
775 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
776 			    u32 *fd_type, const char **buf,
777 			    u64 *probe_offset, u64 *probe_addr,
778 			    unsigned long *missed);
779 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
780 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
781 #else
trace_call_bpf(struct trace_event_call * call,void * ctx)782 static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
783 {
784 	return 1;
785 }
786 
787 static inline int
perf_event_attach_bpf_prog(struct perf_event * event,struct bpf_prog * prog,u64 bpf_cookie)788 perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie)
789 {
790 	return -EOPNOTSUPP;
791 }
792 
perf_event_detach_bpf_prog(struct perf_event * event)793 static inline void perf_event_detach_bpf_prog(struct perf_event *event) { }
794 
795 static inline int
perf_event_query_prog_array(struct perf_event * event,void __user * info)796 perf_event_query_prog_array(struct perf_event *event, void __user *info)
797 {
798 	return -EOPNOTSUPP;
799 }
800 struct bpf_raw_tp_link;
bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)801 static inline int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
802 {
803 	return -EOPNOTSUPP;
804 }
bpf_probe_unregister(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)805 static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
806 {
807 	return -EOPNOTSUPP;
808 }
bpf_get_raw_tracepoint(const char * name)809 static inline struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
810 {
811 	return NULL;
812 }
bpf_put_raw_tracepoint(struct bpf_raw_event_map * btp)813 static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
814 {
815 }
bpf_get_perf_event_info(const struct perf_event * event,u32 * prog_id,u32 * fd_type,const char ** buf,u64 * probe_offset,u64 * probe_addr,unsigned long * missed)816 static inline int bpf_get_perf_event_info(const struct perf_event *event,
817 					  u32 *prog_id, u32 *fd_type,
818 					  const char **buf, u64 *probe_offset,
819 					  u64 *probe_addr, unsigned long *missed)
820 {
821 	return -EOPNOTSUPP;
822 }
823 static inline int
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)824 bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
825 {
826 	return -EOPNOTSUPP;
827 }
828 static inline int
bpf_uprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)829 bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
830 {
831 	return -EOPNOTSUPP;
832 }
833 #endif
834 
835 enum {
836 	FILTER_OTHER = 0,
837 	FILTER_STATIC_STRING,
838 	FILTER_DYN_STRING,
839 	FILTER_RDYN_STRING,
840 	FILTER_PTR_STRING,
841 	FILTER_TRACE_FN,
842 	FILTER_CPUMASK,
843 	FILTER_COMM,
844 	FILTER_CPU,
845 	FILTER_STACKTRACE,
846 };
847 
848 extern int trace_event_raw_init(struct trace_event_call *call);
849 extern int trace_define_field(struct trace_event_call *call, const char *type,
850 			      const char *name, int offset, int size,
851 			      int is_signed, int filter_type);
852 extern int trace_add_event_call(struct trace_event_call *call);
853 extern int trace_remove_event_call(struct trace_event_call *call);
854 extern int trace_event_get_offsets(struct trace_event_call *call);
855 
856 int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
857 int trace_set_clr_event(const char *system, const char *event, int set);
858 int trace_array_set_clr_event(struct trace_array *tr, const char *system,
859 		const char *event, bool enable);
860 
861 #ifdef CONFIG_PERF_EVENTS
862 struct perf_event;
863 
864 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
865 
866 extern int  perf_trace_init(struct perf_event *event);
867 extern void perf_trace_destroy(struct perf_event *event);
868 extern int  perf_trace_add(struct perf_event *event, int flags);
869 extern void perf_trace_del(struct perf_event *event, int flags);
870 #ifdef CONFIG_KPROBE_EVENTS
871 extern int  perf_kprobe_init(struct perf_event *event, bool is_retprobe);
872 extern void perf_kprobe_destroy(struct perf_event *event);
873 extern int bpf_get_kprobe_info(const struct perf_event *event,
874 			       u32 *fd_type, const char **symbol,
875 			       u64 *probe_offset, u64 *probe_addr,
876 			       unsigned long *missed,
877 			       bool perf_type_tracepoint);
878 #endif
879 #ifdef CONFIG_UPROBE_EVENTS
880 extern int  perf_uprobe_init(struct perf_event *event,
881 			     unsigned long ref_ctr_offset, bool is_retprobe);
882 extern void perf_uprobe_destroy(struct perf_event *event);
883 extern int bpf_get_uprobe_info(const struct perf_event *event,
884 			       u32 *fd_type, const char **filename,
885 			       u64 *probe_offset, u64 *probe_addr,
886 			       bool perf_type_tracepoint);
887 #endif
888 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
889 				     char *filter_str);
890 extern void ftrace_profile_free_filter(struct perf_event *event);
891 void perf_trace_buf_update(void *record, u16 type);
892 void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp);
893 
894 int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
895 void perf_event_free_bpf_prog(struct perf_event *event);
896 
897 void bpf_trace_run1(struct bpf_raw_tp_link *link, u64 arg1);
898 void bpf_trace_run2(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2);
899 void bpf_trace_run3(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
900 		    u64 arg3);
901 void bpf_trace_run4(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
902 		    u64 arg3, u64 arg4);
903 void bpf_trace_run5(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
904 		    u64 arg3, u64 arg4, u64 arg5);
905 void bpf_trace_run6(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
906 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6);
907 void bpf_trace_run7(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
908 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7);
909 void bpf_trace_run8(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
910 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
911 		    u64 arg8);
912 void bpf_trace_run9(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
913 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
914 		    u64 arg8, u64 arg9);
915 void bpf_trace_run10(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
916 		     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
917 		     u64 arg8, u64 arg9, u64 arg10);
918 void bpf_trace_run11(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
919 		     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
920 		     u64 arg8, u64 arg9, u64 arg10, u64 arg11);
921 void bpf_trace_run12(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
922 		     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
923 		     u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12);
924 void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
925 			       struct trace_event_call *call, u64 count,
926 			       struct pt_regs *regs, struct hlist_head *head,
927 			       struct task_struct *task);
928 
929 static inline void
perf_trace_buf_submit(void * raw_data,int size,int rctx,u16 type,u64 count,struct pt_regs * regs,void * head,struct task_struct * task)930 perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type,
931 		       u64 count, struct pt_regs *regs, void *head,
932 		       struct task_struct *task)
933 {
934 	perf_tp_event(type, count, raw_data, size, regs, head, rctx, task);
935 }
936 
937 #endif
938 
939 #define TRACE_EVENT_STR_MAX	512
940 
941 /*
942  * gcc warns that you can not use a va_list in an inlined
943  * function. But lets me make it into a macro :-/
944  */
945 #define __trace_event_vstr_len(fmt, va)			\
946 ({							\
947 	va_list __ap;					\
948 	int __ret;					\
949 							\
950 	va_copy(__ap, *(va));				\
951 	__ret = vsnprintf(NULL, 0, fmt, __ap) + 1;	\
952 	va_end(__ap);					\
953 							\
954 	min(__ret, TRACE_EVENT_STR_MAX);		\
955 })
956 
957 #endif /* _LINUX_TRACE_EVENT_H */
958 
959 /*
960  * Note: we keep the TRACE_CUSTOM_EVENT outside the include file ifdef protection.
961  *  This is due to the way trace custom events work. If a file includes two
962  *  trace event headers under one "CREATE_CUSTOM_TRACE_EVENTS" the first include
963  *  will override the TRACE_CUSTOM_EVENT and break the second include.
964  */
965 
966 #ifndef TRACE_CUSTOM_EVENT
967 
968 #define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print)
969 #define DEFINE_CUSTOM_EVENT(template, name, proto, args)
970 #define TRACE_CUSTOM_EVENT(name, proto, args, struct, assign, print)
971 
972 #endif /* ifdef TRACE_CUSTOM_EVENT (see note above) */
973