xref: /linux/include/linux/trace_events.h (revision c061cf420ded391e32f99cd483e1e0107f213b12)
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 };
142 
143 
144 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
145 				      int flags, struct trace_event *event);
146 
147 struct trace_event_functions {
148 	trace_print_func	trace;
149 	trace_print_func	raw;
150 	trace_print_func	hex;
151 	trace_print_func	binary;
152 };
153 
154 struct trace_event {
155 	struct hlist_node		node;
156 	int				type;
157 	struct trace_event_functions	*funcs;
158 };
159 
160 extern int register_trace_event(struct trace_event *event);
161 extern int unregister_trace_event(struct trace_event *event);
162 
163 /* Return values for print_line callback */
164 enum print_line_t {
165 	TRACE_TYPE_PARTIAL_LINE	= 0,	/* Retry after flushing the seq */
166 	TRACE_TYPE_HANDLED	= 1,
167 	TRACE_TYPE_UNHANDLED	= 2,	/* Relay to other output functions */
168 	TRACE_TYPE_NO_CONSUME	= 3	/* Handled but ask to not consume */
169 };
170 
171 enum print_line_t trace_handle_return(struct trace_seq *s);
172 
tracing_generic_entry_update(struct trace_entry * entry,unsigned short type,unsigned int trace_ctx)173 static inline void tracing_generic_entry_update(struct trace_entry *entry,
174 						unsigned short type,
175 						unsigned int trace_ctx)
176 {
177 	entry->preempt_count		= trace_ctx & 0xff;
178 	entry->pid			= current->pid;
179 	entry->type			= type;
180 	entry->flags =			trace_ctx >> 16;
181 }
182 
183 unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
184 
185 enum trace_flag_type {
186 	TRACE_FLAG_IRQS_OFF		= 0x01,
187 	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x02,
188 	TRACE_FLAG_NEED_RESCHED		= 0x04,
189 	TRACE_FLAG_HARDIRQ		= 0x08,
190 	TRACE_FLAG_SOFTIRQ		= 0x10,
191 	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
192 	TRACE_FLAG_NMI			= 0x40,
193 	TRACE_FLAG_BH_OFF		= 0x80,
194 };
195 
tracing_gen_ctx_flags(unsigned long irqflags)196 static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
197 {
198 	unsigned int irq_status = irqs_disabled_flags(irqflags) ?
199 		TRACE_FLAG_IRQS_OFF : 0;
200 	return tracing_gen_ctx_irq_test(irq_status);
201 }
tracing_gen_ctx(void)202 static inline unsigned int tracing_gen_ctx(void)
203 {
204 	unsigned long irqflags;
205 
206 	local_save_flags(irqflags);
207 	return tracing_gen_ctx_flags(irqflags);
208 }
209 
tracing_gen_ctx_dec(void)210 static inline unsigned int tracing_gen_ctx_dec(void)
211 {
212 	unsigned int trace_ctx;
213 
214 	trace_ctx = tracing_gen_ctx();
215 	/*
216 	 * Subtract one from the preemption counter if preemption is enabled,
217 	 * see trace_event_buffer_reserve()for details.
218 	 */
219 	if (IS_ENABLED(CONFIG_PREEMPTION))
220 		trace_ctx--;
221 	return trace_ctx;
222 }
223 
224 struct trace_event_file;
225 
226 struct ring_buffer_event *
227 trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
228 				struct trace_event_file *trace_file,
229 				int type, unsigned long len,
230 				unsigned int trace_ctx);
231 
232 #define TRACE_RECORD_CMDLINE	BIT(0)
233 #define TRACE_RECORD_TGID	BIT(1)
234 
235 void tracing_record_taskinfo(struct task_struct *task, int flags);
236 void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
237 					  struct task_struct *next, int flags);
238 
239 void tracing_record_cmdline(struct task_struct *task);
240 void tracing_record_tgid(struct task_struct *task);
241 
242 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
243 	 __printf(3, 4);
244 
245 struct event_filter;
246 
247 enum trace_reg {
248 	TRACE_REG_REGISTER,
249 	TRACE_REG_UNREGISTER,
250 #ifdef CONFIG_PERF_EVENTS
251 	TRACE_REG_PERF_REGISTER,
252 	TRACE_REG_PERF_UNREGISTER,
253 	TRACE_REG_PERF_OPEN,
254 	TRACE_REG_PERF_CLOSE,
255 	/*
256 	 * These (ADD/DEL) use a 'boolean' return value, where 1 (true) means a
257 	 * custom action was taken and the default action is not to be
258 	 * performed.
259 	 */
260 	TRACE_REG_PERF_ADD,
261 	TRACE_REG_PERF_DEL,
262 #endif
263 };
264 
265 struct trace_event_call;
266 
267 #define TRACE_FUNCTION_TYPE ((const char *)~0UL)
268 
269 struct trace_event_fields {
270 	const char *type;
271 	union {
272 		struct {
273 			const char *name;
274 			const int  size;
275 			const int  align;
276 			const unsigned int is_signed:1;
277 			unsigned int needs_test:1;
278 			const int  filter_type;
279 			const int  len;
280 		};
281 		int (*define_fields)(struct trace_event_call *);
282 	};
283 };
284 
285 struct trace_event_class {
286 	const char		*system;
287 	void			*probe;
288 #ifdef CONFIG_PERF_EVENTS
289 	void			*perf_probe;
290 #endif
291 	int			(*reg)(struct trace_event_call *event,
292 				       enum trace_reg type, void *data);
293 	struct trace_event_fields *fields_array;
294 	struct list_head	*(*get_fields)(struct trace_event_call *);
295 	struct list_head	fields;
296 	int			(*raw_init)(struct trace_event_call *);
297 };
298 
299 extern int trace_event_reg(struct trace_event_call *event,
300 			    enum trace_reg type, void *data);
301 
302 struct trace_event_buffer {
303 	struct trace_buffer		*buffer;
304 	struct ring_buffer_event	*event;
305 	struct trace_event_file		*trace_file;
306 	void				*entry;
307 	unsigned int			trace_ctx;
308 	struct pt_regs			*regs;
309 };
310 
311 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
312 				  struct trace_event_file *trace_file,
313 				  unsigned long len);
314 
315 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
316 
317 enum {
318 	TRACE_EVENT_FL_CAP_ANY_BIT,
319 	TRACE_EVENT_FL_NO_SET_FILTER_BIT,
320 	TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
321 	TRACE_EVENT_FL_TRACEPOINT_BIT,
322 	TRACE_EVENT_FL_DYNAMIC_BIT,
323 	TRACE_EVENT_FL_KPROBE_BIT,
324 	TRACE_EVENT_FL_UPROBE_BIT,
325 	TRACE_EVENT_FL_EPROBE_BIT,
326 	TRACE_EVENT_FL_FPROBE_BIT,
327 	TRACE_EVENT_FL_CUSTOM_BIT,
328 	TRACE_EVENT_FL_TEST_STR_BIT,
329 };
330 
331 /*
332  * Event flags:
333  *  CAP_ANY	  - Any user can enable for perf
334  *  NO_SET_FILTER - Set when filter has error and is to be ignored
335  *  IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
336  *  TRACEPOINT    - Event is a tracepoint
337  *  DYNAMIC       - Event is a dynamic event (created at run time)
338  *  KPROBE        - Event is a kprobe
339  *  UPROBE        - Event is a uprobe
340  *  EPROBE        - Event is an event probe
341  *  FPROBE        - Event is an function probe
342  *  CUSTOM        - Event is a custom event (to be attached to an exsiting tracepoint)
343  *                   This is set when the custom event has not been attached
344  *                   to a tracepoint yet, then it is cleared when it is.
345  *  TEST_STR      - The event has a "%s" that points to a string outside the event
346  */
347 enum {
348 	TRACE_EVENT_FL_CAP_ANY		= (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
349 	TRACE_EVENT_FL_NO_SET_FILTER	= (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
350 	TRACE_EVENT_FL_IGNORE_ENABLE	= (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
351 	TRACE_EVENT_FL_TRACEPOINT	= (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
352 	TRACE_EVENT_FL_DYNAMIC		= (1 << TRACE_EVENT_FL_DYNAMIC_BIT),
353 	TRACE_EVENT_FL_KPROBE		= (1 << TRACE_EVENT_FL_KPROBE_BIT),
354 	TRACE_EVENT_FL_UPROBE		= (1 << TRACE_EVENT_FL_UPROBE_BIT),
355 	TRACE_EVENT_FL_EPROBE		= (1 << TRACE_EVENT_FL_EPROBE_BIT),
356 	TRACE_EVENT_FL_FPROBE		= (1 << TRACE_EVENT_FL_FPROBE_BIT),
357 	TRACE_EVENT_FL_CUSTOM		= (1 << TRACE_EVENT_FL_CUSTOM_BIT),
358 	TRACE_EVENT_FL_TEST_STR		= (1 << TRACE_EVENT_FL_TEST_STR_BIT),
359 };
360 
361 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
362 
363 struct trace_event_call {
364 	struct list_head	list;
365 	struct trace_event_class *class;
366 	union {
367 		char			*name;
368 		/* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
369 		struct tracepoint	*tp;
370 	};
371 	struct trace_event	event;
372 	char			*print_fmt;
373 	/*
374 	 * Static events can disappear with modules,
375 	 * where as dynamic ones need their own ref count.
376 	 */
377 	union {
378 		void				*module;
379 		atomic_t			refcnt;
380 	};
381 	void			*data;
382 
383 	/* See the TRACE_EVENT_FL_* flags above */
384 	int			flags; /* static flags of different events */
385 
386 #ifdef CONFIG_PERF_EVENTS
387 	int				perf_refcount;
388 	struct hlist_head __percpu	*perf_events;
389 	struct bpf_prog_array __rcu	*prog_array;
390 
391 	int	(*perf_perm)(struct trace_event_call *,
392 			     struct perf_event *);
393 #endif
394 };
395 
396 #ifdef CONFIG_DYNAMIC_EVENTS
397 bool trace_event_dyn_try_get_ref(struct trace_event_call *call);
398 void trace_event_dyn_put_ref(struct trace_event_call *call);
399 bool trace_event_dyn_busy(struct trace_event_call *call);
400 #else
trace_event_dyn_try_get_ref(struct trace_event_call * call)401 static inline bool trace_event_dyn_try_get_ref(struct trace_event_call *call)
402 {
403 	/* Without DYNAMIC_EVENTS configured, nothing should be calling this */
404 	return false;
405 }
trace_event_dyn_put_ref(struct trace_event_call * call)406 static inline void trace_event_dyn_put_ref(struct trace_event_call *call)
407 {
408 }
trace_event_dyn_busy(struct trace_event_call * call)409 static inline bool trace_event_dyn_busy(struct trace_event_call *call)
410 {
411 	/* Nothing should call this without DYNAIMIC_EVENTS configured. */
412 	return true;
413 }
414 #endif
415 
trace_event_try_get_ref(struct trace_event_call * call)416 static inline bool trace_event_try_get_ref(struct trace_event_call *call)
417 {
418 	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
419 		return trace_event_dyn_try_get_ref(call);
420 	else
421 		return try_module_get(call->module);
422 }
423 
trace_event_put_ref(struct trace_event_call * call)424 static inline void trace_event_put_ref(struct trace_event_call *call)
425 {
426 	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
427 		trace_event_dyn_put_ref(call);
428 	else
429 		module_put(call->module);
430 }
431 
432 #ifdef CONFIG_PERF_EVENTS
bpf_prog_array_valid(struct trace_event_call * call)433 static inline bool bpf_prog_array_valid(struct trace_event_call *call)
434 {
435 	/*
436 	 * This inline function checks whether call->prog_array
437 	 * is valid or not. The function is called in various places,
438 	 * outside rcu_read_lock/unlock, as a heuristic to speed up execution.
439 	 *
440 	 * If this function returns true, and later call->prog_array
441 	 * becomes false inside rcu_read_lock/unlock region,
442 	 * we bail out then. If this function return false,
443 	 * there is a risk that we might miss a few events if the checking
444 	 * were delayed until inside rcu_read_lock/unlock region and
445 	 * call->prog_array happened to become non-NULL then.
446 	 *
447 	 * Here, READ_ONCE() is used instead of rcu_access_pointer().
448 	 * rcu_access_pointer() requires the actual definition of
449 	 * "struct bpf_prog_array" while READ_ONCE() only needs
450 	 * a declaration of the same type.
451 	 */
452 	return !!READ_ONCE(call->prog_array);
453 }
454 #endif
455 
456 static inline const char *
trace_event_name(struct trace_event_call * call)457 trace_event_name(struct trace_event_call *call)
458 {
459 	if (call->flags & TRACE_EVENT_FL_CUSTOM)
460 		return call->name;
461 	else if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
462 		return call->tp ? call->tp->name : NULL;
463 	else
464 		return call->name;
465 }
466 
467 static inline struct list_head *
trace_get_fields(struct trace_event_call * event_call)468 trace_get_fields(struct trace_event_call *event_call)
469 {
470 	if (!event_call->class->get_fields)
471 		return &event_call->class->fields;
472 	return event_call->class->get_fields(event_call);
473 }
474 
475 struct trace_subsystem_dir;
476 
477 enum {
478 	EVENT_FILE_FL_ENABLED_BIT,
479 	EVENT_FILE_FL_RECORDED_CMD_BIT,
480 	EVENT_FILE_FL_RECORDED_TGID_BIT,
481 	EVENT_FILE_FL_FILTERED_BIT,
482 	EVENT_FILE_FL_NO_SET_FILTER_BIT,
483 	EVENT_FILE_FL_SOFT_MODE_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_MODE     - The event is enabled/disabled by SOFT_DISABLED
622  *  SOFT_DISABLED - When set, do not trace the event (even though its
623  *                   tracepoint may be enabled)
624  *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
625  *  TRIGGER_COND  - When set, one or more triggers has an associated filter
626  *  PID_FILTER    - When set, the event is filtered based on pid
627  *  WAS_ENABLED   - Set when enabled to know to clear trace on module removal
628  *  FREED         - File descriptor is freed, all fields should be considered invalid
629  */
630 enum {
631 	EVENT_FILE_FL_ENABLED		= (1 << EVENT_FILE_FL_ENABLED_BIT),
632 	EVENT_FILE_FL_RECORDED_CMD	= (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
633 	EVENT_FILE_FL_RECORDED_TGID	= (1 << EVENT_FILE_FL_RECORDED_TGID_BIT),
634 	EVENT_FILE_FL_FILTERED		= (1 << EVENT_FILE_FL_FILTERED_BIT),
635 	EVENT_FILE_FL_NO_SET_FILTER	= (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
636 	EVENT_FILE_FL_SOFT_MODE		= (1 << EVENT_FILE_FL_SOFT_MODE_BIT),
637 	EVENT_FILE_FL_SOFT_DISABLED	= (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
638 	EVENT_FILE_FL_TRIGGER_MODE	= (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
639 	EVENT_FILE_FL_TRIGGER_COND	= (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
640 	EVENT_FILE_FL_PID_FILTER	= (1 << EVENT_FILE_FL_PID_FILTER_BIT),
641 	EVENT_FILE_FL_WAS_ENABLED	= (1 << EVENT_FILE_FL_WAS_ENABLED_BIT),
642 	EVENT_FILE_FL_FREED		= (1 << EVENT_FILE_FL_FREED_BIT),
643 };
644 
645 struct trace_event_file {
646 	struct list_head		list;
647 	struct trace_event_call		*event_call;
648 	struct event_filter __rcu	*filter;
649 	struct eventfs_inode		*ei;
650 	struct trace_array		*tr;
651 	struct trace_subsystem_dir	*system;
652 	struct list_head		triggers;
653 
654 	/*
655 	 * 32 bit flags:
656 	 *   bit 0:		enabled
657 	 *   bit 1:		enabled cmd record
658 	 *   bit 2:		enable/disable with the soft disable bit
659 	 *   bit 3:		soft disabled
660 	 *   bit 4:		trigger enabled
661 	 *
662 	 * Note: The bits must be set atomically to prevent races
663 	 * from other writers. Reads of flags do not need to be in
664 	 * sync as they occur in critical sections. But the way flags
665 	 * is currently used, these changes do not affect the code
666 	 * except that when a change is made, it may have a slight
667 	 * delay in propagating the changes to other CPUs due to
668 	 * caching and such. Which is mostly OK ;-)
669 	 */
670 	unsigned long		flags;
671 	refcount_t		ref;	/* ref count for opened files */
672 	atomic_t		sm_ref;	/* soft-mode reference counter */
673 	atomic_t		tm_ref;	/* trigger-mode reference counter */
674 };
675 
676 #define __TRACE_EVENT_FLAGS(name, value)				\
677 	static int __init trace_init_flags_##name(void)			\
678 	{								\
679 		event_##name.flags |= value;				\
680 		return 0;						\
681 	}								\
682 	early_initcall(trace_init_flags_##name);
683 
684 #define __TRACE_EVENT_PERF_PERM(name, expr...)				\
685 	static int perf_perm_##name(struct trace_event_call *tp_event, \
686 				    struct perf_event *p_event)		\
687 	{								\
688 		return ({ expr; });					\
689 	}								\
690 	static int __init trace_init_perf_perm_##name(void)		\
691 	{								\
692 		event_##name.perf_perm = &perf_perm_##name;		\
693 		return 0;						\
694 	}								\
695 	early_initcall(trace_init_perf_perm_##name);
696 
697 #define PERF_MAX_TRACE_SIZE	8192
698 
699 #define MAX_FILTER_STR_VAL	256U	/* Should handle KSYM_SYMBOL_LEN */
700 
701 enum event_trigger_type {
702 	ETT_NONE		= (0),
703 	ETT_TRACE_ONOFF		= (1 << 0),
704 	ETT_SNAPSHOT		= (1 << 1),
705 	ETT_STACKTRACE		= (1 << 2),
706 	ETT_EVENT_ENABLE	= (1 << 3),
707 	ETT_EVENT_HIST		= (1 << 4),
708 	ETT_HIST_ENABLE		= (1 << 5),
709 	ETT_EVENT_EPROBE	= (1 << 6),
710 };
711 
712 extern int filter_match_preds(struct event_filter *filter, void *rec);
713 
714 extern enum event_trigger_type
715 event_triggers_call(struct trace_event_file *file,
716 		    struct trace_buffer *buffer, void *rec,
717 		    struct ring_buffer_event *event);
718 extern void
719 event_triggers_post_call(struct trace_event_file *file,
720 			 enum event_trigger_type tt);
721 
722 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
723 
724 bool __trace_trigger_soft_disabled(struct trace_event_file *file);
725 
726 /**
727  * trace_trigger_soft_disabled - do triggers and test if soft disabled
728  * @file: The file pointer of the event to test
729  *
730  * If any triggers without filters are attached to this event, they
731  * will be called here. If the event is soft disabled and has no
732  * triggers that require testing the fields, it will return true,
733  * otherwise false.
734  */
735 static __always_inline bool
trace_trigger_soft_disabled(struct trace_event_file * file)736 trace_trigger_soft_disabled(struct trace_event_file *file)
737 {
738 	unsigned long eflags = file->flags;
739 
740 	if (likely(!(eflags & (EVENT_FILE_FL_TRIGGER_MODE |
741 			       EVENT_FILE_FL_SOFT_DISABLED |
742 			       EVENT_FILE_FL_PID_FILTER))))
743 		return false;
744 
745 	if (likely(eflags & EVENT_FILE_FL_TRIGGER_COND))
746 		return false;
747 
748 	return __trace_trigger_soft_disabled(file);
749 }
750 
751 #ifdef CONFIG_BPF_EVENTS
752 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx);
753 int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
754 void perf_event_detach_bpf_prog(struct perf_event *event);
755 int perf_event_query_prog_array(struct perf_event *event, void __user *info);
756 
757 struct bpf_raw_tp_link;
758 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
759 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link);
760 
761 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name);
762 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp);
763 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
764 			    u32 *fd_type, const char **buf,
765 			    u64 *probe_offset, u64 *probe_addr,
766 			    unsigned long *missed);
767 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
768 int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
769 #else
trace_call_bpf(struct trace_event_call * call,void * ctx)770 static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
771 {
772 	return 1;
773 }
774 
775 static inline int
perf_event_attach_bpf_prog(struct perf_event * event,struct bpf_prog * prog,u64 bpf_cookie)776 perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie)
777 {
778 	return -EOPNOTSUPP;
779 }
780 
perf_event_detach_bpf_prog(struct perf_event * event)781 static inline void perf_event_detach_bpf_prog(struct perf_event *event) { }
782 
783 static inline int
perf_event_query_prog_array(struct perf_event * event,void __user * info)784 perf_event_query_prog_array(struct perf_event *event, void __user *info)
785 {
786 	return -EOPNOTSUPP;
787 }
788 struct bpf_raw_tp_link;
bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)789 static inline int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
790 {
791 	return -EOPNOTSUPP;
792 }
bpf_probe_unregister(struct bpf_raw_event_map * btp,struct bpf_raw_tp_link * link)793 static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link)
794 {
795 	return -EOPNOTSUPP;
796 }
bpf_get_raw_tracepoint(const char * name)797 static inline struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
798 {
799 	return NULL;
800 }
bpf_put_raw_tracepoint(struct bpf_raw_event_map * btp)801 static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
802 {
803 }
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)804 static inline int bpf_get_perf_event_info(const struct perf_event *event,
805 					  u32 *prog_id, u32 *fd_type,
806 					  const char **buf, u64 *probe_offset,
807 					  u64 *probe_addr, unsigned long *missed)
808 {
809 	return -EOPNOTSUPP;
810 }
811 static inline int
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)812 bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
813 {
814 	return -EOPNOTSUPP;
815 }
816 static inline int
bpf_uprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)817 bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
818 {
819 	return -EOPNOTSUPP;
820 }
821 #endif
822 
823 enum {
824 	FILTER_OTHER = 0,
825 	FILTER_STATIC_STRING,
826 	FILTER_DYN_STRING,
827 	FILTER_RDYN_STRING,
828 	FILTER_PTR_STRING,
829 	FILTER_TRACE_FN,
830 	FILTER_CPUMASK,
831 	FILTER_COMM,
832 	FILTER_CPU,
833 	FILTER_STACKTRACE,
834 };
835 
836 extern int trace_event_raw_init(struct trace_event_call *call);
837 extern int trace_define_field(struct trace_event_call *call, const char *type,
838 			      const char *name, int offset, int size,
839 			      int is_signed, int filter_type);
840 extern int trace_add_event_call(struct trace_event_call *call);
841 extern int trace_remove_event_call(struct trace_event_call *call);
842 extern int trace_event_get_offsets(struct trace_event_call *call);
843 
844 int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
845 int trace_set_clr_event(const char *system, const char *event, int set);
846 int trace_array_set_clr_event(struct trace_array *tr, const char *system,
847 		const char *event, bool enable);
848 /*
849  * The double __builtin_constant_p is because gcc will give us an error
850  * if we try to allocate the static variable to fmt if it is not a
851  * constant. Even with the outer if statement optimizing out.
852  */
853 #define event_trace_printk(ip, fmt, args...)				\
854 do {									\
855 	__trace_printk_check_format(fmt, ##args);			\
856 	tracing_record_cmdline(current);				\
857 	if (__builtin_constant_p(fmt)) {				\
858 		static const char *trace_printk_fmt			\
859 		  __section("__trace_printk_fmt") =			\
860 			__builtin_constant_p(fmt) ? fmt : NULL;		\
861 									\
862 		__trace_bprintk(ip, trace_printk_fmt, ##args);		\
863 	} else								\
864 		__trace_printk(ip, fmt, ##args);			\
865 } while (0)
866 
867 #ifdef CONFIG_PERF_EVENTS
868 struct perf_event;
869 
870 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
871 
872 extern int  perf_trace_init(struct perf_event *event);
873 extern void perf_trace_destroy(struct perf_event *event);
874 extern int  perf_trace_add(struct perf_event *event, int flags);
875 extern void perf_trace_del(struct perf_event *event, int flags);
876 #ifdef CONFIG_KPROBE_EVENTS
877 extern int  perf_kprobe_init(struct perf_event *event, bool is_retprobe);
878 extern void perf_kprobe_destroy(struct perf_event *event);
879 extern int bpf_get_kprobe_info(const struct perf_event *event,
880 			       u32 *fd_type, const char **symbol,
881 			       u64 *probe_offset, u64 *probe_addr,
882 			       unsigned long *missed,
883 			       bool perf_type_tracepoint);
884 #endif
885 #ifdef CONFIG_UPROBE_EVENTS
886 extern int  perf_uprobe_init(struct perf_event *event,
887 			     unsigned long ref_ctr_offset, bool is_retprobe);
888 extern void perf_uprobe_destroy(struct perf_event *event);
889 extern int bpf_get_uprobe_info(const struct perf_event *event,
890 			       u32 *fd_type, const char **filename,
891 			       u64 *probe_offset, u64 *probe_addr,
892 			       bool perf_type_tracepoint);
893 #endif
894 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
895 				     char *filter_str);
896 extern void ftrace_profile_free_filter(struct perf_event *event);
897 void perf_trace_buf_update(void *record, u16 type);
898 void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp);
899 
900 int perf_event_set_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie);
901 void perf_event_free_bpf_prog(struct perf_event *event);
902 
903 void bpf_trace_run1(struct bpf_raw_tp_link *link, u64 arg1);
904 void bpf_trace_run2(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2);
905 void bpf_trace_run3(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
906 		    u64 arg3);
907 void bpf_trace_run4(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
908 		    u64 arg3, u64 arg4);
909 void bpf_trace_run5(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
910 		    u64 arg3, u64 arg4, u64 arg5);
911 void bpf_trace_run6(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
912 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6);
913 void bpf_trace_run7(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
914 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7);
915 void bpf_trace_run8(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
916 		    u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
917 		    u64 arg8);
918 void bpf_trace_run9(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);
921 void bpf_trace_run10(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);
924 void bpf_trace_run11(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
925 		     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
926 		     u64 arg8, u64 arg9, u64 arg10, u64 arg11);
927 void bpf_trace_run12(struct bpf_raw_tp_link *link, u64 arg1, u64 arg2,
928 		     u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
929 		     u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12);
930 void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
931 			       struct trace_event_call *call, u64 count,
932 			       struct pt_regs *regs, struct hlist_head *head,
933 			       struct task_struct *task);
934 
935 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)936 perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type,
937 		       u64 count, struct pt_regs *regs, void *head,
938 		       struct task_struct *task)
939 {
940 	perf_tp_event(type, count, raw_data, size, regs, head, rctx, task);
941 }
942 
943 #endif
944 
945 #define TRACE_EVENT_STR_MAX	512
946 
947 /*
948  * gcc warns that you can not use a va_list in an inlined
949  * function. But lets me make it into a macro :-/
950  */
951 #define __trace_event_vstr_len(fmt, va)			\
952 ({							\
953 	va_list __ap;					\
954 	int __ret;					\
955 							\
956 	va_copy(__ap, *(va));				\
957 	__ret = vsnprintf(NULL, 0, fmt, __ap) + 1;	\
958 	va_end(__ap);					\
959 							\
960 	min(__ret, TRACE_EVENT_STR_MAX);		\
961 })
962 
963 #endif /* _LINUX_TRACE_EVENT_H */
964 
965 /*
966  * Note: we keep the TRACE_CUSTOM_EVENT outside the include file ifdef protection.
967  *  This is due to the way trace custom events work. If a file includes two
968  *  trace event headers under one "CREATE_CUSTOM_TRACE_EVENTS" the first include
969  *  will override the TRACE_CUSTOM_EVENT and break the second include.
970  */
971 
972 #ifndef TRACE_CUSTOM_EVENT
973 
974 #define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print)
975 #define DEFINE_CUSTOM_EVENT(template, name, proto, args)
976 #define TRACE_CUSTOM_EVENT(name, proto, args, struct, assign, print)
977 
978 #endif /* ifdef TRACE_CUSTOM_EVENT (see note above) */
979