xref: /openbmc/linux/kernel/trace/trace.h (revision 060f03e9)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5 
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24 
25 #include "pid_list.h"
26 
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h>		/* For NR_syscalls	     */
29 #include <asm/syscall.h>	/* some archs define it here */
30 #endif
31 
32 #define TRACE_MODE_WRITE	0640
33 #define TRACE_MODE_READ		0440
34 
35 enum trace_type {
36 	__TRACE_FIRST_TYPE = 0,
37 
38 	TRACE_FN,
39 	TRACE_CTX,
40 	TRACE_WAKE,
41 	TRACE_STACK,
42 	TRACE_PRINT,
43 	TRACE_BPRINT,
44 	TRACE_MMIO_RW,
45 	TRACE_MMIO_MAP,
46 	TRACE_BRANCH,
47 	TRACE_GRAPH_RET,
48 	TRACE_GRAPH_ENT,
49 	TRACE_USER_STACK,
50 	TRACE_BLK,
51 	TRACE_BPUTS,
52 	TRACE_HWLAT,
53 	TRACE_OSNOISE,
54 	TRACE_TIMERLAT,
55 	TRACE_RAW_DATA,
56 	TRACE_FUNC_REPEATS,
57 
58 	__TRACE_LAST_TYPE,
59 };
60 
61 
62 #undef __field
63 #define __field(type, item)		type	item;
64 
65 #undef __field_fn
66 #define __field_fn(type, item)		type	item;
67 
68 #undef __field_struct
69 #define __field_struct(type, item)	__field(type, item)
70 
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73 
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76 
77 #undef __array
78 #define __array(type, item, size)	type	item[size];
79 
80 #undef __array_desc
81 #define __array_desc(type, container, item, size)
82 
83 #undef __dynamic_array
84 #define __dynamic_array(type, item)	type	item[];
85 
86 #undef __rel_dynamic_array
87 #define __rel_dynamic_array(type, item)	type	item[];
88 
89 #undef F_STRUCT
90 #define F_STRUCT(args...)		args
91 
92 #undef FTRACE_ENTRY
93 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
94 	struct struct_name {						\
95 		struct trace_entry	ent;				\
96 		tstruct							\
97 	}
98 
99 #undef FTRACE_ENTRY_DUP
100 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
101 
102 #undef FTRACE_ENTRY_REG
103 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
104 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
105 
106 #undef FTRACE_ENTRY_PACKED
107 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
108 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
109 
110 #include "trace_entries.h"
111 
112 /* Use this for memory failure errors */
113 #define MEM_FAIL(condition, fmt, ...)					\
114 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
115 
116 #define HIST_STACKTRACE_DEPTH	16
117 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
118 #define HIST_STACKTRACE_SKIP	5
119 
120 /*
121  * syscalls are special, and need special handling, this is why
122  * they are not included in trace_entries.h
123  */
124 struct syscall_trace_enter {
125 	struct trace_entry	ent;
126 	int			nr;
127 	unsigned long		args[];
128 };
129 
130 struct syscall_trace_exit {
131 	struct trace_entry	ent;
132 	int			nr;
133 	long			ret;
134 };
135 
136 struct kprobe_trace_entry_head {
137 	struct trace_entry	ent;
138 	unsigned long		ip;
139 };
140 
141 struct eprobe_trace_entry_head {
142 	struct trace_entry	ent;
143 };
144 
145 struct kretprobe_trace_entry_head {
146 	struct trace_entry	ent;
147 	unsigned long		func;
148 	unsigned long		ret_ip;
149 };
150 
151 struct fentry_trace_entry_head {
152 	struct trace_entry	ent;
153 	unsigned long		ip;
154 };
155 
156 struct fexit_trace_entry_head {
157 	struct trace_entry	ent;
158 	unsigned long		func;
159 	unsigned long		ret_ip;
160 };
161 
162 #define TRACE_BUF_SIZE		1024
163 
164 struct trace_array;
165 
166 /*
167  * The CPU trace array - it consists of thousands of trace entries
168  * plus some other descriptor data: (for example which task started
169  * the trace, etc.)
170  */
171 struct trace_array_cpu {
172 	atomic_t		disabled;
173 	void			*buffer_page;	/* ring buffer spare */
174 
175 	unsigned long		entries;
176 	unsigned long		saved_latency;
177 	unsigned long		critical_start;
178 	unsigned long		critical_end;
179 	unsigned long		critical_sequence;
180 	unsigned long		nice;
181 	unsigned long		policy;
182 	unsigned long		rt_priority;
183 	unsigned long		skipped_entries;
184 	u64			preempt_timestamp;
185 	pid_t			pid;
186 	kuid_t			uid;
187 	char			comm[TASK_COMM_LEN];
188 
189 #ifdef CONFIG_FUNCTION_TRACER
190 	int			ftrace_ignore_pid;
191 #endif
192 	bool			ignore_pid;
193 };
194 
195 struct tracer;
196 struct trace_option_dentry;
197 
198 struct array_buffer {
199 	struct trace_array		*tr;
200 	struct trace_buffer		*buffer;
201 	struct trace_array_cpu __percpu	*data;
202 	u64				time_start;
203 	int				cpu;
204 };
205 
206 #define TRACE_FLAGS_MAX_SIZE		32
207 
208 struct trace_options {
209 	struct tracer			*tracer;
210 	struct trace_option_dentry	*topts;
211 };
212 
213 struct trace_pid_list *trace_pid_list_alloc(void);
214 void trace_pid_list_free(struct trace_pid_list *pid_list);
215 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
216 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
217 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
218 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
219 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
220 			unsigned int *next);
221 
222 enum {
223 	TRACE_PIDS		= BIT(0),
224 	TRACE_NO_PIDS		= BIT(1),
225 };
226 
227 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
228 				    struct trace_pid_list *no_pid_list)
229 {
230 	/* Return true if the pid list in type has pids */
231 	return ((type & TRACE_PIDS) && pid_list) ||
232 		((type & TRACE_NO_PIDS) && no_pid_list);
233 }
234 
235 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
236 					 struct trace_pid_list *no_pid_list)
237 {
238 	/*
239 	 * Turning off what is in @type, return true if the "other"
240 	 * pid list, still has pids in it.
241 	 */
242 	return (!(type & TRACE_PIDS) && pid_list) ||
243 		(!(type & TRACE_NO_PIDS) && no_pid_list);
244 }
245 
246 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
247 
248 /**
249  * struct cond_snapshot - conditional snapshot data and callback
250  *
251  * The cond_snapshot structure encapsulates a callback function and
252  * data associated with the snapshot for a given tracing instance.
253  *
254  * When a snapshot is taken conditionally, by invoking
255  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
256  * passed in turn to the cond_snapshot.update() function.  That data
257  * can be compared by the update() implementation with the cond_data
258  * contained within the struct cond_snapshot instance associated with
259  * the trace_array.  Because the tr->max_lock is held throughout the
260  * update() call, the update() function can directly retrieve the
261  * cond_snapshot and cond_data associated with the per-instance
262  * snapshot associated with the trace_array.
263  *
264  * The cond_snapshot.update() implementation can save data to be
265  * associated with the snapshot if it decides to, and returns 'true'
266  * in that case, or it returns 'false' if the conditional snapshot
267  * shouldn't be taken.
268  *
269  * The cond_snapshot instance is created and associated with the
270  * user-defined cond_data by tracing_cond_snapshot_enable().
271  * Likewise, the cond_snapshot instance is destroyed and is no longer
272  * associated with the trace instance by
273  * tracing_cond_snapshot_disable().
274  *
275  * The method below is required.
276  *
277  * @update: When a conditional snapshot is invoked, the update()
278  *	callback function is invoked with the tr->max_lock held.  The
279  *	update() implementation signals whether or not to actually
280  *	take the snapshot, by returning 'true' if so, 'false' if no
281  *	snapshot should be taken.  Because the max_lock is held for
282  *	the duration of update(), the implementation is safe to
283  *	directly retrieved and save any implementation data it needs
284  *	to in association with the snapshot.
285  */
286 struct cond_snapshot {
287 	void				*cond_data;
288 	cond_update_fn_t		update;
289 };
290 
291 /*
292  * struct trace_func_repeats - used to keep track of the consecutive
293  * (on the same CPU) calls of a single function.
294  */
295 struct trace_func_repeats {
296 	unsigned long	ip;
297 	unsigned long	parent_ip;
298 	unsigned long	count;
299 	u64		ts_last_call;
300 };
301 
302 /*
303  * The trace array - an array of per-CPU trace arrays. This is the
304  * highest level data structure that individual tracers deal with.
305  * They have on/off state as well:
306  */
307 struct trace_array {
308 	struct list_head	list;
309 	char			*name;
310 	struct array_buffer	array_buffer;
311 #ifdef CONFIG_TRACER_MAX_TRACE
312 	/*
313 	 * The max_buffer is used to snapshot the trace when a maximum
314 	 * latency is reached, or when the user initiates a snapshot.
315 	 * Some tracers will use this to store a maximum trace while
316 	 * it continues examining live traces.
317 	 *
318 	 * The buffers for the max_buffer are set up the same as the array_buffer
319 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
320 	 * with the buffer of the array_buffer and the buffers are reset for
321 	 * the array_buffer so the tracing can continue.
322 	 */
323 	struct array_buffer	max_buffer;
324 	bool			allocated_snapshot;
325 #endif
326 #ifdef CONFIG_TRACER_MAX_TRACE
327 	unsigned long		max_latency;
328 #ifdef CONFIG_FSNOTIFY
329 	struct dentry		*d_max_latency;
330 	struct work_struct	fsnotify_work;
331 	struct irq_work		fsnotify_irqwork;
332 #endif
333 #endif
334 	struct trace_pid_list	__rcu *filtered_pids;
335 	struct trace_pid_list	__rcu *filtered_no_pids;
336 	/*
337 	 * max_lock is used to protect the swapping of buffers
338 	 * when taking a max snapshot. The buffers themselves are
339 	 * protected by per_cpu spinlocks. But the action of the swap
340 	 * needs its own lock.
341 	 *
342 	 * This is defined as a arch_spinlock_t in order to help
343 	 * with performance when lockdep debugging is enabled.
344 	 *
345 	 * It is also used in other places outside the update_max_tr
346 	 * so it needs to be defined outside of the
347 	 * CONFIG_TRACER_MAX_TRACE.
348 	 */
349 	arch_spinlock_t		max_lock;
350 	int			buffer_disabled;
351 #ifdef CONFIG_FTRACE_SYSCALLS
352 	int			sys_refcount_enter;
353 	int			sys_refcount_exit;
354 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
355 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
356 #endif
357 	int			stop_count;
358 	int			clock_id;
359 	int			nr_topts;
360 	bool			clear_trace;
361 	int			buffer_percent;
362 	unsigned int		n_err_log_entries;
363 	struct tracer		*current_trace;
364 	unsigned int		trace_flags;
365 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
366 	unsigned int		flags;
367 	raw_spinlock_t		start_lock;
368 	struct list_head	err_log;
369 	struct dentry		*dir;
370 	struct dentry		*options;
371 	struct dentry		*percpu_dir;
372 	struct dentry		*event_dir;
373 	struct trace_options	*topts;
374 	struct list_head	systems;
375 	struct list_head	events;
376 	struct trace_event_file *trace_marker_file;
377 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
378 	int			ref;
379 	int			trace_ref;
380 #ifdef CONFIG_FUNCTION_TRACER
381 	struct ftrace_ops	*ops;
382 	struct trace_pid_list	__rcu *function_pids;
383 	struct trace_pid_list	__rcu *function_no_pids;
384 #ifdef CONFIG_DYNAMIC_FTRACE
385 	/* All of these are protected by the ftrace_lock */
386 	struct list_head	func_probes;
387 	struct list_head	mod_trace;
388 	struct list_head	mod_notrace;
389 #endif
390 	/* function tracing enabled */
391 	int			function_enabled;
392 #endif
393 	int			no_filter_buffering_ref;
394 	struct list_head	hist_vars;
395 #ifdef CONFIG_TRACER_SNAPSHOT
396 	struct cond_snapshot	*cond_snapshot;
397 #endif
398 	struct trace_func_repeats	__percpu *last_func_repeats;
399 };
400 
401 enum {
402 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
403 };
404 
405 extern struct list_head ftrace_trace_arrays;
406 
407 extern struct mutex trace_types_lock;
408 
409 extern int trace_array_get(struct trace_array *tr);
410 extern int tracing_check_open_get_tr(struct trace_array *tr);
411 extern struct trace_array *trace_array_find(const char *instance);
412 extern struct trace_array *trace_array_find_get(const char *instance);
413 
414 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
415 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
416 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
417 
418 extern bool trace_clock_in_ns(struct trace_array *tr);
419 
420 /*
421  * The global tracer (top) should be the first trace array added,
422  * but we check the flag anyway.
423  */
424 static inline struct trace_array *top_trace_array(void)
425 {
426 	struct trace_array *tr;
427 
428 	if (list_empty(&ftrace_trace_arrays))
429 		return NULL;
430 
431 	tr = list_entry(ftrace_trace_arrays.prev,
432 			typeof(*tr), list);
433 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
434 	return tr;
435 }
436 
437 #define FTRACE_CMP_TYPE(var, type) \
438 	__builtin_types_compatible_p(typeof(var), type *)
439 
440 #undef IF_ASSIGN
441 #define IF_ASSIGN(var, entry, etype, id)			\
442 	if (FTRACE_CMP_TYPE(var, etype)) {			\
443 		var = (typeof(var))(entry);			\
444 		WARN_ON(id != 0 && (entry)->type != id);	\
445 		break;						\
446 	}
447 
448 /* Will cause compile errors if type is not found. */
449 extern void __ftrace_bad_type(void);
450 
451 /*
452  * The trace_assign_type is a verifier that the entry type is
453  * the same as the type being assigned. To add new types simply
454  * add a line with the following format:
455  *
456  * IF_ASSIGN(var, ent, type, id);
457  *
458  *  Where "type" is the trace type that includes the trace_entry
459  *  as the "ent" item. And "id" is the trace identifier that is
460  *  used in the trace_type enum.
461  *
462  *  If the type can have more than one id, then use zero.
463  */
464 #define trace_assign_type(var, ent)					\
465 	do {								\
466 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
467 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
468 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
469 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
470 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
471 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
472 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
473 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
474 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
475 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
476 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
477 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
478 			  TRACE_MMIO_RW);				\
479 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
480 			  TRACE_MMIO_MAP);				\
481 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
482 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
483 			  TRACE_GRAPH_ENT);		\
484 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
485 			  TRACE_GRAPH_RET);		\
486 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
487 			  TRACE_FUNC_REPEATS);				\
488 		__ftrace_bad_type();					\
489 	} while (0)
490 
491 /*
492  * An option specific to a tracer. This is a boolean value.
493  * The bit is the bit index that sets its value on the
494  * flags value in struct tracer_flags.
495  */
496 struct tracer_opt {
497 	const char	*name; /* Will appear on the trace_options file */
498 	u32		bit; /* Mask assigned in val field in tracer_flags */
499 };
500 
501 /*
502  * The set of specific options for a tracer. Your tracer
503  * have to set the initial value of the flags val.
504  */
505 struct tracer_flags {
506 	u32			val;
507 	struct tracer_opt	*opts;
508 	struct tracer		*trace;
509 };
510 
511 /* Makes more easy to define a tracer opt */
512 #define TRACER_OPT(s, b)	.name = #s, .bit = b
513 
514 
515 struct trace_option_dentry {
516 	struct tracer_opt		*opt;
517 	struct tracer_flags		*flags;
518 	struct trace_array		*tr;
519 	struct dentry			*entry;
520 };
521 
522 /**
523  * struct tracer - a specific tracer and its callbacks to interact with tracefs
524  * @name: the name chosen to select it on the available_tracers file
525  * @init: called when one switches to this tracer (echo name > current_tracer)
526  * @reset: called when one switches to another tracer
527  * @start: called when tracing is unpaused (echo 1 > tracing_on)
528  * @stop: called when tracing is paused (echo 0 > tracing_on)
529  * @update_thresh: called when tracing_thresh is updated
530  * @open: called when the trace file is opened
531  * @pipe_open: called when the trace_pipe file is opened
532  * @close: called when the trace file is released
533  * @pipe_close: called when the trace_pipe file is released
534  * @read: override the default read callback on trace_pipe
535  * @splice_read: override the default splice_read callback on trace_pipe
536  * @selftest: selftest to run on boot (see trace_selftest.c)
537  * @print_headers: override the first lines that describe your columns
538  * @print_line: callback that prints a trace
539  * @set_flag: signals one of your private flags changed (trace_options file)
540  * @flags: your private flags
541  */
542 struct tracer {
543 	const char		*name;
544 	int			(*init)(struct trace_array *tr);
545 	void			(*reset)(struct trace_array *tr);
546 	void			(*start)(struct trace_array *tr);
547 	void			(*stop)(struct trace_array *tr);
548 	int			(*update_thresh)(struct trace_array *tr);
549 	void			(*open)(struct trace_iterator *iter);
550 	void			(*pipe_open)(struct trace_iterator *iter);
551 	void			(*close)(struct trace_iterator *iter);
552 	void			(*pipe_close)(struct trace_iterator *iter);
553 	ssize_t			(*read)(struct trace_iterator *iter,
554 					struct file *filp, char __user *ubuf,
555 					size_t cnt, loff_t *ppos);
556 	ssize_t			(*splice_read)(struct trace_iterator *iter,
557 					       struct file *filp,
558 					       loff_t *ppos,
559 					       struct pipe_inode_info *pipe,
560 					       size_t len,
561 					       unsigned int flags);
562 #ifdef CONFIG_FTRACE_STARTUP_TEST
563 	int			(*selftest)(struct tracer *trace,
564 					    struct trace_array *tr);
565 #endif
566 	void			(*print_header)(struct seq_file *m);
567 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
568 	/* If you handled the flag setting, return 0 */
569 	int			(*set_flag)(struct trace_array *tr,
570 					    u32 old_flags, u32 bit, int set);
571 	/* Return 0 if OK with change, else return non-zero */
572 	int			(*flag_changed)(struct trace_array *tr,
573 						u32 mask, int set);
574 	struct tracer		*next;
575 	struct tracer_flags	*flags;
576 	int			enabled;
577 	bool			print_max;
578 	bool			allow_instances;
579 #ifdef CONFIG_TRACER_MAX_TRACE
580 	bool			use_max_tr;
581 #endif
582 	/* True if tracer cannot be enabled in kernel param */
583 	bool			noboot;
584 };
585 
586 static inline struct ring_buffer_iter *
587 trace_buffer_iter(struct trace_iterator *iter, int cpu)
588 {
589 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
590 }
591 
592 int tracer_init(struct tracer *t, struct trace_array *tr);
593 int tracing_is_enabled(void);
594 void tracing_reset_online_cpus(struct array_buffer *buf);
595 void tracing_reset_current(int cpu);
596 void tracing_reset_all_online_cpus(void);
597 void tracing_reset_all_online_cpus_unlocked(void);
598 int tracing_open_generic(struct inode *inode, struct file *filp);
599 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
600 bool tracing_is_disabled(void);
601 bool tracer_tracing_is_on(struct trace_array *tr);
602 void tracer_tracing_on(struct trace_array *tr);
603 void tracer_tracing_off(struct trace_array *tr);
604 struct dentry *trace_create_file(const char *name,
605 				 umode_t mode,
606 				 struct dentry *parent,
607 				 void *data,
608 				 const struct file_operations *fops);
609 
610 int tracing_init_dentry(void);
611 
612 struct ring_buffer_event;
613 
614 struct ring_buffer_event *
615 trace_buffer_lock_reserve(struct trace_buffer *buffer,
616 			  int type,
617 			  unsigned long len,
618 			  unsigned int trace_ctx);
619 
620 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
621 						struct trace_array_cpu *data);
622 
623 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
624 					  int *ent_cpu, u64 *ent_ts);
625 
626 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
627 					struct ring_buffer_event *event);
628 
629 bool trace_is_tracepoint_string(const char *str);
630 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
631 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
632 			 va_list ap) __printf(2, 0);
633 char *trace_iter_expand_format(struct trace_iterator *iter);
634 
635 int trace_empty(struct trace_iterator *iter);
636 
637 void *trace_find_next_entry_inc(struct trace_iterator *iter);
638 
639 void trace_init_global_iter(struct trace_iterator *iter);
640 
641 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
642 
643 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
644 unsigned long trace_total_entries(struct trace_array *tr);
645 
646 void trace_function(struct trace_array *tr,
647 		    unsigned long ip,
648 		    unsigned long parent_ip,
649 		    unsigned int trace_ctx);
650 void trace_graph_function(struct trace_array *tr,
651 		    unsigned long ip,
652 		    unsigned long parent_ip,
653 		    unsigned int trace_ctx);
654 void trace_latency_header(struct seq_file *m);
655 void trace_default_header(struct seq_file *m);
656 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
657 
658 void trace_graph_return(struct ftrace_graph_ret *trace);
659 int trace_graph_entry(struct ftrace_graph_ent *trace);
660 void set_graph_array(struct trace_array *tr);
661 
662 void tracing_start_cmdline_record(void);
663 void tracing_stop_cmdline_record(void);
664 void tracing_start_tgid_record(void);
665 void tracing_stop_tgid_record(void);
666 
667 int register_tracer(struct tracer *type);
668 int is_tracing_stopped(void);
669 
670 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
671 
672 extern cpumask_var_t __read_mostly tracing_buffer_mask;
673 
674 #define for_each_tracing_cpu(cpu)	\
675 	for_each_cpu(cpu, tracing_buffer_mask)
676 
677 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
678 
679 extern unsigned long tracing_thresh;
680 
681 /* PID filtering */
682 
683 extern int pid_max;
684 
685 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
686 			     pid_t search_pid);
687 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
688 			    struct trace_pid_list *filtered_no_pids,
689 			    struct task_struct *task);
690 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
691 				  struct task_struct *self,
692 				  struct task_struct *task);
693 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
694 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
695 int trace_pid_show(struct seq_file *m, void *v);
696 void trace_free_pid_list(struct trace_pid_list *pid_list);
697 int trace_pid_write(struct trace_pid_list *filtered_pids,
698 		    struct trace_pid_list **new_pid_list,
699 		    const char __user *ubuf, size_t cnt);
700 
701 #ifdef CONFIG_TRACER_MAX_TRACE
702 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
703 		   void *cond_data);
704 void update_max_tr_single(struct trace_array *tr,
705 			  struct task_struct *tsk, int cpu);
706 
707 #ifdef CONFIG_FSNOTIFY
708 #define LATENCY_FS_NOTIFY
709 #endif
710 #endif /* CONFIG_TRACER_MAX_TRACE */
711 
712 #ifdef LATENCY_FS_NOTIFY
713 void latency_fsnotify(struct trace_array *tr);
714 #else
715 static inline void latency_fsnotify(struct trace_array *tr) { }
716 #endif
717 
718 #ifdef CONFIG_STACKTRACE
719 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
720 #else
721 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
722 				 int skip)
723 {
724 }
725 #endif /* CONFIG_STACKTRACE */
726 
727 void trace_last_func_repeats(struct trace_array *tr,
728 			     struct trace_func_repeats *last_info,
729 			     unsigned int trace_ctx);
730 
731 extern u64 ftrace_now(int cpu);
732 
733 extern void trace_find_cmdline(int pid, char comm[]);
734 extern int trace_find_tgid(int pid);
735 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
736 
737 #ifdef CONFIG_DYNAMIC_FTRACE
738 extern unsigned long ftrace_update_tot_cnt;
739 extern unsigned long ftrace_number_of_pages;
740 extern unsigned long ftrace_number_of_groups;
741 void ftrace_init_trace_array(struct trace_array *tr);
742 #else
743 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
744 #endif
745 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
746 extern int DYN_FTRACE_TEST_NAME(void);
747 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
748 extern int DYN_FTRACE_TEST_NAME2(void);
749 
750 extern bool ring_buffer_expanded;
751 extern bool tracing_selftest_disabled;
752 
753 #ifdef CONFIG_FTRACE_STARTUP_TEST
754 extern void __init disable_tracing_selftest(const char *reason);
755 
756 extern int trace_selftest_startup_function(struct tracer *trace,
757 					   struct trace_array *tr);
758 extern int trace_selftest_startup_function_graph(struct tracer *trace,
759 						 struct trace_array *tr);
760 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
761 					  struct trace_array *tr);
762 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
763 					     struct trace_array *tr);
764 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
765 						 struct trace_array *tr);
766 extern int trace_selftest_startup_wakeup(struct tracer *trace,
767 					 struct trace_array *tr);
768 extern int trace_selftest_startup_nop(struct tracer *trace,
769 					 struct trace_array *tr);
770 extern int trace_selftest_startup_branch(struct tracer *trace,
771 					 struct trace_array *tr);
772 /*
773  * Tracer data references selftest functions that only occur
774  * on boot up. These can be __init functions. Thus, when selftests
775  * are enabled, then the tracers need to reference __init functions.
776  */
777 #define __tracer_data		__refdata
778 #else
779 static inline void __init disable_tracing_selftest(const char *reason)
780 {
781 }
782 /* Tracers are seldom changed. Optimize when selftests are disabled. */
783 #define __tracer_data		__read_mostly
784 #endif /* CONFIG_FTRACE_STARTUP_TEST */
785 
786 extern void *head_page(struct trace_array_cpu *data);
787 extern unsigned long long ns2usecs(u64 nsec);
788 extern int
789 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
790 extern int
791 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
792 extern int
793 trace_array_vprintk(struct trace_array *tr,
794 		    unsigned long ip, const char *fmt, va_list args);
795 int trace_array_printk_buf(struct trace_buffer *buffer,
796 			   unsigned long ip, const char *fmt, ...);
797 void trace_printk_seq(struct trace_seq *s);
798 enum print_line_t print_trace_line(struct trace_iterator *iter);
799 
800 extern char trace_find_mark(unsigned long long duration);
801 
802 struct ftrace_hash;
803 
804 struct ftrace_mod_load {
805 	struct list_head	list;
806 	char			*func;
807 	char			*module;
808 	int			 enable;
809 };
810 
811 enum {
812 	FTRACE_HASH_FL_MOD	= (1 << 0),
813 };
814 
815 struct ftrace_hash {
816 	unsigned long		size_bits;
817 	struct hlist_head	*buckets;
818 	unsigned long		count;
819 	unsigned long		flags;
820 	struct rcu_head		rcu;
821 };
822 
823 struct ftrace_func_entry *
824 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
825 
826 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
827 {
828 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
829 }
830 
831 /* Standard output formatting function used for function return traces */
832 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
833 
834 /* Flag options */
835 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
836 #define TRACE_GRAPH_PRINT_CPU           0x2
837 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
838 #define TRACE_GRAPH_PRINT_PROC          0x8
839 #define TRACE_GRAPH_PRINT_DURATION      0x10
840 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
841 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
842 #define TRACE_GRAPH_PRINT_IRQS          0x80
843 #define TRACE_GRAPH_PRINT_TAIL          0x100
844 #define TRACE_GRAPH_SLEEP_TIME          0x200
845 #define TRACE_GRAPH_GRAPH_TIME          0x400
846 #define TRACE_GRAPH_PRINT_RETVAL        0x800
847 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
848 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
849 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
850 
851 extern void ftrace_graph_sleep_time_control(bool enable);
852 
853 #ifdef CONFIG_FUNCTION_PROFILER
854 extern void ftrace_graph_graph_time_control(bool enable);
855 #else
856 static inline void ftrace_graph_graph_time_control(bool enable) { }
857 #endif
858 
859 extern enum print_line_t
860 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
861 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
862 extern void
863 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
864 extern void graph_trace_open(struct trace_iterator *iter);
865 extern void graph_trace_close(struct trace_iterator *iter);
866 extern int __trace_graph_entry(struct trace_array *tr,
867 			       struct ftrace_graph_ent *trace,
868 			       unsigned int trace_ctx);
869 extern void __trace_graph_return(struct trace_array *tr,
870 				 struct ftrace_graph_ret *trace,
871 				 unsigned int trace_ctx);
872 
873 #ifdef CONFIG_DYNAMIC_FTRACE
874 extern struct ftrace_hash __rcu *ftrace_graph_hash;
875 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
876 
877 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
878 {
879 	unsigned long addr = trace->func;
880 	int ret = 0;
881 	struct ftrace_hash *hash;
882 
883 	preempt_disable_notrace();
884 
885 	/*
886 	 * Have to open code "rcu_dereference_sched()" because the
887 	 * function graph tracer can be called when RCU is not
888 	 * "watching".
889 	 * Protected with schedule_on_each_cpu(ftrace_sync)
890 	 */
891 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
892 
893 	if (ftrace_hash_empty(hash)) {
894 		ret = 1;
895 		goto out;
896 	}
897 
898 	if (ftrace_lookup_ip(hash, addr)) {
899 
900 		/*
901 		 * This needs to be cleared on the return functions
902 		 * when the depth is zero.
903 		 */
904 		trace_recursion_set(TRACE_GRAPH_BIT);
905 		trace_recursion_set_depth(trace->depth);
906 
907 		/*
908 		 * If no irqs are to be traced, but a set_graph_function
909 		 * is set, and called by an interrupt handler, we still
910 		 * want to trace it.
911 		 */
912 		if (in_hardirq())
913 			trace_recursion_set(TRACE_IRQ_BIT);
914 		else
915 			trace_recursion_clear(TRACE_IRQ_BIT);
916 		ret = 1;
917 	}
918 
919 out:
920 	preempt_enable_notrace();
921 	return ret;
922 }
923 
924 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
925 {
926 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
927 	    trace->depth == trace_recursion_depth())
928 		trace_recursion_clear(TRACE_GRAPH_BIT);
929 }
930 
931 static inline int ftrace_graph_notrace_addr(unsigned long addr)
932 {
933 	int ret = 0;
934 	struct ftrace_hash *notrace_hash;
935 
936 	preempt_disable_notrace();
937 
938 	/*
939 	 * Have to open code "rcu_dereference_sched()" because the
940 	 * function graph tracer can be called when RCU is not
941 	 * "watching".
942 	 * Protected with schedule_on_each_cpu(ftrace_sync)
943 	 */
944 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
945 						 !preemptible());
946 
947 	if (ftrace_lookup_ip(notrace_hash, addr))
948 		ret = 1;
949 
950 	preempt_enable_notrace();
951 	return ret;
952 }
953 #else
954 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
955 {
956 	return 1;
957 }
958 
959 static inline int ftrace_graph_notrace_addr(unsigned long addr)
960 {
961 	return 0;
962 }
963 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
964 { }
965 #endif /* CONFIG_DYNAMIC_FTRACE */
966 
967 extern unsigned int fgraph_max_depth;
968 
969 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
970 {
971 	/* trace it when it is-nested-in or is a function enabled. */
972 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
973 		 ftrace_graph_addr(trace)) ||
974 		(trace->depth < 0) ||
975 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
976 }
977 
978 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
979 static inline enum print_line_t
980 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
981 {
982 	return TRACE_TYPE_UNHANDLED;
983 }
984 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
985 
986 extern struct list_head ftrace_pids;
987 
988 #ifdef CONFIG_FUNCTION_TRACER
989 
990 #define FTRACE_PID_IGNORE	-1
991 #define FTRACE_PID_TRACE	-2
992 
993 struct ftrace_func_command {
994 	struct list_head	list;
995 	char			*name;
996 	int			(*func)(struct trace_array *tr,
997 					struct ftrace_hash *hash,
998 					char *func, char *cmd,
999 					char *params, int enable);
1000 };
1001 extern bool ftrace_filter_param __initdata;
1002 static inline int ftrace_trace_task(struct trace_array *tr)
1003 {
1004 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1005 		FTRACE_PID_IGNORE;
1006 }
1007 extern int ftrace_is_dead(void);
1008 int ftrace_create_function_files(struct trace_array *tr,
1009 				 struct dentry *parent);
1010 void ftrace_destroy_function_files(struct trace_array *tr);
1011 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1012 void ftrace_free_ftrace_ops(struct trace_array *tr);
1013 void ftrace_init_global_array_ops(struct trace_array *tr);
1014 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1015 void ftrace_reset_array_ops(struct trace_array *tr);
1016 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1017 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1018 				  struct dentry *d_tracer);
1019 void ftrace_clear_pids(struct trace_array *tr);
1020 int init_function_trace(void);
1021 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1022 #else
1023 static inline int ftrace_trace_task(struct trace_array *tr)
1024 {
1025 	return 1;
1026 }
1027 static inline int ftrace_is_dead(void) { return 0; }
1028 static inline int
1029 ftrace_create_function_files(struct trace_array *tr,
1030 			     struct dentry *parent)
1031 {
1032 	return 0;
1033 }
1034 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1035 {
1036 	return 0;
1037 }
1038 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1039 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1040 static inline __init void
1041 ftrace_init_global_array_ops(struct trace_array *tr) { }
1042 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1043 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1044 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1045 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1046 static inline int init_function_trace(void) { return 0; }
1047 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1048 /* ftace_func_t type is not defined, use macro instead of static inline */
1049 #define ftrace_init_array_ops(tr, func) do { } while (0)
1050 #endif /* CONFIG_FUNCTION_TRACER */
1051 
1052 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1053 
1054 struct ftrace_probe_ops {
1055 	void			(*func)(unsigned long ip,
1056 					unsigned long parent_ip,
1057 					struct trace_array *tr,
1058 					struct ftrace_probe_ops *ops,
1059 					void *data);
1060 	int			(*init)(struct ftrace_probe_ops *ops,
1061 					struct trace_array *tr,
1062 					unsigned long ip, void *init_data,
1063 					void **data);
1064 	void			(*free)(struct ftrace_probe_ops *ops,
1065 					struct trace_array *tr,
1066 					unsigned long ip, void *data);
1067 	int			(*print)(struct seq_file *m,
1068 					 unsigned long ip,
1069 					 struct ftrace_probe_ops *ops,
1070 					 void *data);
1071 };
1072 
1073 struct ftrace_func_mapper;
1074 typedef int (*ftrace_mapper_func)(void *data);
1075 
1076 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1077 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1078 					   unsigned long ip);
1079 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1080 			       unsigned long ip, void *data);
1081 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1082 				   unsigned long ip);
1083 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1084 			     ftrace_mapper_func free_func);
1085 
1086 extern int
1087 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1088 			       struct ftrace_probe_ops *ops, void *data);
1089 extern int
1090 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1091 				      struct ftrace_probe_ops *ops);
1092 extern void clear_ftrace_function_probes(struct trace_array *tr);
1093 
1094 int register_ftrace_command(struct ftrace_func_command *cmd);
1095 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1096 
1097 void ftrace_create_filter_files(struct ftrace_ops *ops,
1098 				struct dentry *parent);
1099 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1100 
1101 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1102 			     int len, int reset);
1103 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1104 			      int len, int reset);
1105 #else
1106 struct ftrace_func_command;
1107 
1108 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1109 {
1110 	return -EINVAL;
1111 }
1112 static inline __init int unregister_ftrace_command(char *cmd_name)
1113 {
1114 	return -EINVAL;
1115 }
1116 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1117 {
1118 }
1119 
1120 /*
1121  * The ops parameter passed in is usually undefined.
1122  * This must be a macro.
1123  */
1124 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1125 #define ftrace_destroy_filter_files(ops) do { } while (0)
1126 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1127 
1128 bool ftrace_event_is_function(struct trace_event_call *call);
1129 
1130 /*
1131  * struct trace_parser - servers for reading the user input separated by spaces
1132  * @cont: set if the input is not complete - no final space char was found
1133  * @buffer: holds the parsed user input
1134  * @idx: user input length
1135  * @size: buffer size
1136  */
1137 struct trace_parser {
1138 	bool		cont;
1139 	char		*buffer;
1140 	unsigned	idx;
1141 	unsigned	size;
1142 };
1143 
1144 static inline bool trace_parser_loaded(struct trace_parser *parser)
1145 {
1146 	return (parser->idx != 0);
1147 }
1148 
1149 static inline bool trace_parser_cont(struct trace_parser *parser)
1150 {
1151 	return parser->cont;
1152 }
1153 
1154 static inline void trace_parser_clear(struct trace_parser *parser)
1155 {
1156 	parser->cont = false;
1157 	parser->idx = 0;
1158 }
1159 
1160 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1161 extern void trace_parser_put(struct trace_parser *parser);
1162 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1163 	size_t cnt, loff_t *ppos);
1164 
1165 /*
1166  * Only create function graph options if function graph is configured.
1167  */
1168 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1169 # define FGRAPH_FLAGS						\
1170 		C(DISPLAY_GRAPH,	"display-graph"),
1171 #else
1172 # define FGRAPH_FLAGS
1173 #endif
1174 
1175 #ifdef CONFIG_BRANCH_TRACER
1176 # define BRANCH_FLAGS					\
1177 		C(BRANCH,		"branch"),
1178 #else
1179 # define BRANCH_FLAGS
1180 #endif
1181 
1182 #ifdef CONFIG_FUNCTION_TRACER
1183 # define FUNCTION_FLAGS						\
1184 		C(FUNCTION,		"function-trace"),	\
1185 		C(FUNC_FORK,		"function-fork"),
1186 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1187 #else
1188 # define FUNCTION_FLAGS
1189 # define FUNCTION_DEFAULT_FLAGS		0UL
1190 # define TRACE_ITER_FUNC_FORK		0UL
1191 #endif
1192 
1193 #ifdef CONFIG_STACKTRACE
1194 # define STACK_FLAGS				\
1195 		C(STACKTRACE,		"stacktrace"),
1196 #else
1197 # define STACK_FLAGS
1198 #endif
1199 
1200 /*
1201  * trace_iterator_flags is an enumeration that defines bit
1202  * positions into trace_flags that controls the output.
1203  *
1204  * NOTE: These bits must match the trace_options array in
1205  *       trace.c (this macro guarantees it).
1206  */
1207 #define TRACE_FLAGS						\
1208 		C(PRINT_PARENT,		"print-parent"),	\
1209 		C(SYM_OFFSET,		"sym-offset"),		\
1210 		C(SYM_ADDR,		"sym-addr"),		\
1211 		C(VERBOSE,		"verbose"),		\
1212 		C(RAW,			"raw"),			\
1213 		C(HEX,			"hex"),			\
1214 		C(BIN,			"bin"),			\
1215 		C(BLOCK,		"block"),		\
1216 		C(FIELDS,		"fields"),		\
1217 		C(PRINTK,		"trace_printk"),	\
1218 		C(ANNOTATE,		"annotate"),		\
1219 		C(USERSTACKTRACE,	"userstacktrace"),	\
1220 		C(SYM_USEROBJ,		"sym-userobj"),		\
1221 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1222 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1223 		C(LATENCY_FMT,		"latency-format"),	\
1224 		C(RECORD_CMD,		"record-cmd"),		\
1225 		C(RECORD_TGID,		"record-tgid"),		\
1226 		C(OVERWRITE,		"overwrite"),		\
1227 		C(STOP_ON_FREE,		"disable_on_free"),	\
1228 		C(IRQ_INFO,		"irq-info"),		\
1229 		C(MARKERS,		"markers"),		\
1230 		C(EVENT_FORK,		"event-fork"),		\
1231 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1232 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1233 		FUNCTION_FLAGS					\
1234 		FGRAPH_FLAGS					\
1235 		STACK_FLAGS					\
1236 		BRANCH_FLAGS
1237 
1238 /*
1239  * By defining C, we can make TRACE_FLAGS a list of bit names
1240  * that will define the bits for the flag masks.
1241  */
1242 #undef C
1243 #define C(a, b) TRACE_ITER_##a##_BIT
1244 
1245 enum trace_iterator_bits {
1246 	TRACE_FLAGS
1247 	/* Make sure we don't go more than we have bits for */
1248 	TRACE_ITER_LAST_BIT
1249 };
1250 
1251 /*
1252  * By redefining C, we can make TRACE_FLAGS a list of masks that
1253  * use the bits as defined above.
1254  */
1255 #undef C
1256 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1257 
1258 enum trace_iterator_flags { TRACE_FLAGS };
1259 
1260 /*
1261  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1262  * control the output of kernel symbols.
1263  */
1264 #define TRACE_ITER_SYM_MASK \
1265 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1266 
1267 extern struct tracer nop_trace;
1268 
1269 #ifdef CONFIG_BRANCH_TRACER
1270 extern int enable_branch_tracing(struct trace_array *tr);
1271 extern void disable_branch_tracing(void);
1272 static inline int trace_branch_enable(struct trace_array *tr)
1273 {
1274 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1275 		return enable_branch_tracing(tr);
1276 	return 0;
1277 }
1278 static inline void trace_branch_disable(void)
1279 {
1280 	/* due to races, always disable */
1281 	disable_branch_tracing();
1282 }
1283 #else
1284 static inline int trace_branch_enable(struct trace_array *tr)
1285 {
1286 	return 0;
1287 }
1288 static inline void trace_branch_disable(void)
1289 {
1290 }
1291 #endif /* CONFIG_BRANCH_TRACER */
1292 
1293 /* set ring buffers to default size if not already done so */
1294 int tracing_update_buffers(void);
1295 
1296 struct ftrace_event_field {
1297 	struct list_head	link;
1298 	const char		*name;
1299 	const char		*type;
1300 	int			filter_type;
1301 	int			offset;
1302 	int			size;
1303 	int			is_signed;
1304 	int			len;
1305 };
1306 
1307 struct prog_entry;
1308 
1309 struct event_filter {
1310 	struct prog_entry __rcu	*prog;
1311 	char			*filter_string;
1312 };
1313 
1314 struct event_subsystem {
1315 	struct list_head	list;
1316 	const char		*name;
1317 	struct event_filter	*filter;
1318 	int			ref_count;
1319 };
1320 
1321 struct trace_subsystem_dir {
1322 	struct list_head		list;
1323 	struct event_subsystem		*subsystem;
1324 	struct trace_array		*tr;
1325 	struct dentry			*entry;
1326 	int				ref_count;
1327 	int				nr_events;
1328 };
1329 
1330 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1331 				     struct trace_buffer *buffer,
1332 				     struct ring_buffer_event *event);
1333 
1334 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1335 				     struct trace_buffer *buffer,
1336 				     struct ring_buffer_event *event,
1337 				     unsigned int trcace_ctx,
1338 				     struct pt_regs *regs);
1339 
1340 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1341 					      struct trace_buffer *buffer,
1342 					      struct ring_buffer_event *event,
1343 					      unsigned int trace_ctx)
1344 {
1345 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1346 }
1347 
1348 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1349 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1350 void trace_buffered_event_disable(void);
1351 void trace_buffered_event_enable(void);
1352 
1353 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1354 
1355 static inline void
1356 __trace_event_discard_commit(struct trace_buffer *buffer,
1357 			     struct ring_buffer_event *event)
1358 {
1359 	if (this_cpu_read(trace_buffered_event) == event) {
1360 		/* Simply release the temp buffer and enable preemption */
1361 		this_cpu_dec(trace_buffered_event_cnt);
1362 		preempt_enable_notrace();
1363 		return;
1364 	}
1365 	/* ring_buffer_discard_commit() enables preemption */
1366 	ring_buffer_discard_commit(buffer, event);
1367 }
1368 
1369 /*
1370  * Helper function for event_trigger_unlock_commit{_regs}().
1371  * If there are event triggers attached to this event that requires
1372  * filtering against its fields, then they will be called as the
1373  * entry already holds the field information of the current event.
1374  *
1375  * It also checks if the event should be discarded or not.
1376  * It is to be discarded if the event is soft disabled and the
1377  * event was only recorded to process triggers, or if the event
1378  * filter is active and this event did not match the filters.
1379  *
1380  * Returns true if the event is discarded, false otherwise.
1381  */
1382 static inline bool
1383 __event_trigger_test_discard(struct trace_event_file *file,
1384 			     struct trace_buffer *buffer,
1385 			     struct ring_buffer_event *event,
1386 			     void *entry,
1387 			     enum event_trigger_type *tt)
1388 {
1389 	unsigned long eflags = file->flags;
1390 
1391 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1392 		*tt = event_triggers_call(file, buffer, entry, event);
1393 
1394 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1395 				    EVENT_FILE_FL_FILTERED |
1396 				    EVENT_FILE_FL_PID_FILTER))))
1397 		return false;
1398 
1399 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1400 		goto discard;
1401 
1402 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1403 	    !filter_match_preds(file->filter, entry))
1404 		goto discard;
1405 
1406 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1407 	    trace_event_ignore_this_pid(file))
1408 		goto discard;
1409 
1410 	return false;
1411  discard:
1412 	__trace_event_discard_commit(buffer, event);
1413 	return true;
1414 }
1415 
1416 /**
1417  * event_trigger_unlock_commit - handle triggers and finish event commit
1418  * @file: The file pointer associated with the event
1419  * @buffer: The ring buffer that the event is being written to
1420  * @event: The event meta data in the ring buffer
1421  * @entry: The event itself
1422  * @trace_ctx: The tracing context flags.
1423  *
1424  * This is a helper function to handle triggers that require data
1425  * from the event itself. It also tests the event against filters and
1426  * if the event is soft disabled and should be discarded.
1427  */
1428 static inline void
1429 event_trigger_unlock_commit(struct trace_event_file *file,
1430 			    struct trace_buffer *buffer,
1431 			    struct ring_buffer_event *event,
1432 			    void *entry, unsigned int trace_ctx)
1433 {
1434 	enum event_trigger_type tt = ETT_NONE;
1435 
1436 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1437 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1438 
1439 	if (tt)
1440 		event_triggers_post_call(file, tt);
1441 }
1442 
1443 #define FILTER_PRED_INVALID	((unsigned short)-1)
1444 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1445 #define FILTER_PRED_FOLD	(1 << 15)
1446 
1447 /*
1448  * The max preds is the size of unsigned short with
1449  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1450  * and FOLD flags. The other is reserved.
1451  *
1452  * 2^14 preds is way more than enough.
1453  */
1454 #define MAX_FILTER_PRED		16384
1455 
1456 struct filter_pred;
1457 struct regex;
1458 
1459 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1460 
1461 enum regex_type {
1462 	MATCH_FULL = 0,
1463 	MATCH_FRONT_ONLY,
1464 	MATCH_MIDDLE_ONLY,
1465 	MATCH_END_ONLY,
1466 	MATCH_GLOB,
1467 	MATCH_INDEX,
1468 };
1469 
1470 struct regex {
1471 	char			pattern[MAX_FILTER_STR_VAL];
1472 	int			len;
1473 	int			field_len;
1474 	regex_match_func	match;
1475 };
1476 
1477 static inline bool is_string_field(struct ftrace_event_field *field)
1478 {
1479 	return field->filter_type == FILTER_DYN_STRING ||
1480 	       field->filter_type == FILTER_RDYN_STRING ||
1481 	       field->filter_type == FILTER_STATIC_STRING ||
1482 	       field->filter_type == FILTER_PTR_STRING ||
1483 	       field->filter_type == FILTER_COMM;
1484 }
1485 
1486 static inline bool is_function_field(struct ftrace_event_field *field)
1487 {
1488 	return field->filter_type == FILTER_TRACE_FN;
1489 }
1490 
1491 extern enum regex_type
1492 filter_parse_regex(char *buff, int len, char **search, int *not);
1493 extern void print_event_filter(struct trace_event_file *file,
1494 			       struct trace_seq *s);
1495 extern int apply_event_filter(struct trace_event_file *file,
1496 			      char *filter_string);
1497 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1498 					char *filter_string);
1499 extern void print_subsystem_event_filter(struct event_subsystem *system,
1500 					 struct trace_seq *s);
1501 extern int filter_assign_type(const char *type);
1502 extern int create_event_filter(struct trace_array *tr,
1503 			       struct trace_event_call *call,
1504 			       char *filter_str, bool set_str,
1505 			       struct event_filter **filterp);
1506 extern void free_event_filter(struct event_filter *filter);
1507 
1508 struct ftrace_event_field *
1509 trace_find_event_field(struct trace_event_call *call, char *name);
1510 
1511 extern void trace_event_enable_cmd_record(bool enable);
1512 extern void trace_event_enable_tgid_record(bool enable);
1513 
1514 extern int event_trace_init(void);
1515 extern int init_events(void);
1516 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1517 extern int event_trace_del_tracer(struct trace_array *tr);
1518 extern void __trace_early_add_events(struct trace_array *tr);
1519 
1520 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1521 						  const char *system,
1522 						  const char *event);
1523 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1524 						const char *system,
1525 						const char *event);
1526 
1527 static inline void *event_file_data(struct file *filp)
1528 {
1529 	return READ_ONCE(file_inode(filp)->i_private);
1530 }
1531 
1532 extern struct mutex event_mutex;
1533 extern struct list_head ftrace_events;
1534 
1535 extern const struct file_operations event_trigger_fops;
1536 extern const struct file_operations event_hist_fops;
1537 extern const struct file_operations event_hist_debug_fops;
1538 extern const struct file_operations event_inject_fops;
1539 
1540 #ifdef CONFIG_HIST_TRIGGERS
1541 extern int register_trigger_hist_cmd(void);
1542 extern int register_trigger_hist_enable_disable_cmds(void);
1543 #else
1544 static inline int register_trigger_hist_cmd(void) { return 0; }
1545 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1546 #endif
1547 
1548 extern int register_trigger_cmds(void);
1549 extern void clear_event_triggers(struct trace_array *tr);
1550 
1551 enum {
1552 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1553 };
1554 
1555 struct event_trigger_data {
1556 	unsigned long			count;
1557 	int				ref;
1558 	int				flags;
1559 	struct event_trigger_ops	*ops;
1560 	struct event_command		*cmd_ops;
1561 	struct event_filter __rcu	*filter;
1562 	char				*filter_str;
1563 	void				*private_data;
1564 	bool				paused;
1565 	bool				paused_tmp;
1566 	struct list_head		list;
1567 	char				*name;
1568 	struct list_head		named_list;
1569 	struct event_trigger_data	*named_data;
1570 };
1571 
1572 /* Avoid typos */
1573 #define ENABLE_EVENT_STR	"enable_event"
1574 #define DISABLE_EVENT_STR	"disable_event"
1575 #define ENABLE_HIST_STR		"enable_hist"
1576 #define DISABLE_HIST_STR	"disable_hist"
1577 
1578 struct enable_trigger_data {
1579 	struct trace_event_file		*file;
1580 	bool				enable;
1581 	bool				hist;
1582 };
1583 
1584 extern int event_enable_trigger_print(struct seq_file *m,
1585 				      struct event_trigger_data *data);
1586 extern void event_enable_trigger_free(struct event_trigger_data *data);
1587 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1588 				      struct trace_event_file *file,
1589 				      char *glob, char *cmd,
1590 				      char *param_and_filter);
1591 extern int event_enable_register_trigger(char *glob,
1592 					 struct event_trigger_data *data,
1593 					 struct trace_event_file *file);
1594 extern void event_enable_unregister_trigger(char *glob,
1595 					    struct event_trigger_data *test,
1596 					    struct trace_event_file *file);
1597 extern void trigger_data_free(struct event_trigger_data *data);
1598 extern int event_trigger_init(struct event_trigger_data *data);
1599 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1600 					      int trigger_enable);
1601 extern void update_cond_flag(struct trace_event_file *file);
1602 extern int set_trigger_filter(char *filter_str,
1603 			      struct event_trigger_data *trigger_data,
1604 			      struct trace_event_file *file);
1605 extern struct event_trigger_data *find_named_trigger(const char *name);
1606 extern bool is_named_trigger(struct event_trigger_data *test);
1607 extern int save_named_trigger(const char *name,
1608 			      struct event_trigger_data *data);
1609 extern void del_named_trigger(struct event_trigger_data *data);
1610 extern void pause_named_trigger(struct event_trigger_data *data);
1611 extern void unpause_named_trigger(struct event_trigger_data *data);
1612 extern void set_named_trigger_data(struct event_trigger_data *data,
1613 				   struct event_trigger_data *named_data);
1614 extern struct event_trigger_data *
1615 get_named_trigger_data(struct event_trigger_data *data);
1616 extern int register_event_command(struct event_command *cmd);
1617 extern int unregister_event_command(struct event_command *cmd);
1618 extern int register_trigger_hist_enable_disable_cmds(void);
1619 extern bool event_trigger_check_remove(const char *glob);
1620 extern bool event_trigger_empty_param(const char *param);
1621 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1622 					 char **filter, bool param_required);
1623 extern struct event_trigger_data *
1624 event_trigger_alloc(struct event_command *cmd_ops,
1625 		    char *cmd,
1626 		    char *param,
1627 		    void *private_data);
1628 extern int event_trigger_parse_num(char *trigger,
1629 				   struct event_trigger_data *trigger_data);
1630 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1631 				    struct trace_event_file *file,
1632 				    char *param,
1633 				    struct event_trigger_data *trigger_data);
1634 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1635 				       struct event_trigger_data *trigger_data);
1636 extern int event_trigger_register(struct event_command *cmd_ops,
1637 				  struct trace_event_file *file,
1638 				  char *glob,
1639 				  struct event_trigger_data *trigger_data);
1640 extern void event_trigger_unregister(struct event_command *cmd_ops,
1641 				     struct trace_event_file *file,
1642 				     char *glob,
1643 				     struct event_trigger_data *trigger_data);
1644 
1645 /**
1646  * struct event_trigger_ops - callbacks for trace event triggers
1647  *
1648  * The methods in this structure provide per-event trigger hooks for
1649  * various trigger operations.
1650  *
1651  * The @init and @free methods are used during trigger setup and
1652  * teardown, typically called from an event_command's @parse()
1653  * function implementation.
1654  *
1655  * The @print method is used to print the trigger spec.
1656  *
1657  * The @trigger method is the function that actually implements the
1658  * trigger and is called in the context of the triggering event
1659  * whenever that event occurs.
1660  *
1661  * All the methods below, except for @init() and @free(), must be
1662  * implemented.
1663  *
1664  * @trigger: The trigger 'probe' function called when the triggering
1665  *	event occurs.  The data passed into this callback is the data
1666  *	that was supplied to the event_command @reg() function that
1667  *	registered the trigger (see struct event_command) along with
1668  *	the trace record, rec.
1669  *
1670  * @init: An optional initialization function called for the trigger
1671  *	when the trigger is registered (via the event_command reg()
1672  *	function).  This can be used to perform per-trigger
1673  *	initialization such as incrementing a per-trigger reference
1674  *	count, for instance.  This is usually implemented by the
1675  *	generic utility function @event_trigger_init() (see
1676  *	trace_event_triggers.c).
1677  *
1678  * @free: An optional de-initialization function called for the
1679  *	trigger when the trigger is unregistered (via the
1680  *	event_command @reg() function).  This can be used to perform
1681  *	per-trigger de-initialization such as decrementing a
1682  *	per-trigger reference count and freeing corresponding trigger
1683  *	data, for instance.  This is usually implemented by the
1684  *	generic utility function @event_trigger_free() (see
1685  *	trace_event_triggers.c).
1686  *
1687  * @print: The callback function invoked to have the trigger print
1688  *	itself.  This is usually implemented by a wrapper function
1689  *	that calls the generic utility function @event_trigger_print()
1690  *	(see trace_event_triggers.c).
1691  */
1692 struct event_trigger_ops {
1693 	void			(*trigger)(struct event_trigger_data *data,
1694 					   struct trace_buffer *buffer,
1695 					   void *rec,
1696 					   struct ring_buffer_event *rbe);
1697 	int			(*init)(struct event_trigger_data *data);
1698 	void			(*free)(struct event_trigger_data *data);
1699 	int			(*print)(struct seq_file *m,
1700 					 struct event_trigger_data *data);
1701 };
1702 
1703 /**
1704  * struct event_command - callbacks and data members for event commands
1705  *
1706  * Event commands are invoked by users by writing the command name
1707  * into the 'trigger' file associated with a trace event.  The
1708  * parameters associated with a specific invocation of an event
1709  * command are used to create an event trigger instance, which is
1710  * added to the list of trigger instances associated with that trace
1711  * event.  When the event is hit, the set of triggers associated with
1712  * that event is invoked.
1713  *
1714  * The data members in this structure provide per-event command data
1715  * for various event commands.
1716  *
1717  * All the data members below, except for @post_trigger, must be set
1718  * for each event command.
1719  *
1720  * @name: The unique name that identifies the event command.  This is
1721  *	the name used when setting triggers via trigger files.
1722  *
1723  * @trigger_type: A unique id that identifies the event command
1724  *	'type'.  This value has two purposes, the first to ensure that
1725  *	only one trigger of the same type can be set at a given time
1726  *	for a particular event e.g. it doesn't make sense to have both
1727  *	a traceon and traceoff trigger attached to a single event at
1728  *	the same time, so traceon and traceoff have the same type
1729  *	though they have different names.  The @trigger_type value is
1730  *	also used as a bit value for deferring the actual trigger
1731  *	action until after the current event is finished.  Some
1732  *	commands need to do this if they themselves log to the trace
1733  *	buffer (see the @post_trigger() member below).  @trigger_type
1734  *	values are defined by adding new values to the trigger_type
1735  *	enum in include/linux/trace_events.h.
1736  *
1737  * @flags: See the enum event_command_flags below.
1738  *
1739  * All the methods below, except for @set_filter() and @unreg_all(),
1740  * must be implemented.
1741  *
1742  * @parse: The callback function responsible for parsing and
1743  *	registering the trigger written to the 'trigger' file by the
1744  *	user.  It allocates the trigger instance and registers it with
1745  *	the appropriate trace event.  It makes use of the other
1746  *	event_command callback functions to orchestrate this, and is
1747  *	usually implemented by the generic utility function
1748  *	@event_trigger_callback() (see trace_event_triggers.c).
1749  *
1750  * @reg: Adds the trigger to the list of triggers associated with the
1751  *	event, and enables the event trigger itself, after
1752  *	initializing it (via the event_trigger_ops @init() function).
1753  *	This is also where commands can use the @trigger_type value to
1754  *	make the decision as to whether or not multiple instances of
1755  *	the trigger should be allowed.  This is usually implemented by
1756  *	the generic utility function @register_trigger() (see
1757  *	trace_event_triggers.c).
1758  *
1759  * @unreg: Removes the trigger from the list of triggers associated
1760  *	with the event, and disables the event trigger itself, after
1761  *	initializing it (via the event_trigger_ops @free() function).
1762  *	This is usually implemented by the generic utility function
1763  *	@unregister_trigger() (see trace_event_triggers.c).
1764  *
1765  * @unreg_all: An optional function called to remove all the triggers
1766  *	from the list of triggers associated with the event.  Called
1767  *	when a trigger file is opened in truncate mode.
1768  *
1769  * @set_filter: An optional function called to parse and set a filter
1770  *	for the trigger.  If no @set_filter() method is set for the
1771  *	event command, filters set by the user for the command will be
1772  *	ignored.  This is usually implemented by the generic utility
1773  *	function @set_trigger_filter() (see trace_event_triggers.c).
1774  *
1775  * @get_trigger_ops: The callback function invoked to retrieve the
1776  *	event_trigger_ops implementation associated with the command.
1777  *	This callback function allows a single event_command to
1778  *	support multiple trigger implementations via different sets of
1779  *	event_trigger_ops, depending on the value of the @param
1780  *	string.
1781  */
1782 struct event_command {
1783 	struct list_head	list;
1784 	char			*name;
1785 	enum event_trigger_type	trigger_type;
1786 	int			flags;
1787 	int			(*parse)(struct event_command *cmd_ops,
1788 					 struct trace_event_file *file,
1789 					 char *glob, char *cmd,
1790 					 char *param_and_filter);
1791 	int			(*reg)(char *glob,
1792 				       struct event_trigger_data *data,
1793 				       struct trace_event_file *file);
1794 	void			(*unreg)(char *glob,
1795 					 struct event_trigger_data *data,
1796 					 struct trace_event_file *file);
1797 	void			(*unreg_all)(struct trace_event_file *file);
1798 	int			(*set_filter)(char *filter_str,
1799 					      struct event_trigger_data *data,
1800 					      struct trace_event_file *file);
1801 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1802 };
1803 
1804 /**
1805  * enum event_command_flags - flags for struct event_command
1806  *
1807  * @POST_TRIGGER: A flag that says whether or not this command needs
1808  *	to have its action delayed until after the current event has
1809  *	been closed.  Some triggers need to avoid being invoked while
1810  *	an event is currently in the process of being logged, since
1811  *	the trigger may itself log data into the trace buffer.  Thus
1812  *	we make sure the current event is committed before invoking
1813  *	those triggers.  To do that, the trigger invocation is split
1814  *	in two - the first part checks the filter using the current
1815  *	trace record; if a command has the @post_trigger flag set, it
1816  *	sets a bit for itself in the return value, otherwise it
1817  *	directly invokes the trigger.  Once all commands have been
1818  *	either invoked or set their return flag, the current record is
1819  *	either committed or discarded.  At that point, if any commands
1820  *	have deferred their triggers, those commands are finally
1821  *	invoked following the close of the current event.  In other
1822  *	words, if the event_trigger_ops @func() probe implementation
1823  *	itself logs to the trace buffer, this flag should be set,
1824  *	otherwise it can be left unspecified.
1825  *
1826  * @NEEDS_REC: A flag that says whether or not this command needs
1827  *	access to the trace record in order to perform its function,
1828  *	regardless of whether or not it has a filter associated with
1829  *	it (filters make a trigger require access to the trace record
1830  *	but are not always present).
1831  */
1832 enum event_command_flags {
1833 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1834 	EVENT_CMD_FL_NEEDS_REC		= 2,
1835 };
1836 
1837 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1838 {
1839 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1840 }
1841 
1842 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1843 {
1844 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1845 }
1846 
1847 extern int trace_event_enable_disable(struct trace_event_file *file,
1848 				      int enable, int soft_disable);
1849 extern int tracing_alloc_snapshot(void);
1850 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1851 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1852 
1853 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1854 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1855 
1856 extern const char *__start___trace_bprintk_fmt[];
1857 extern const char *__stop___trace_bprintk_fmt[];
1858 
1859 extern const char *__start___tracepoint_str[];
1860 extern const char *__stop___tracepoint_str[];
1861 
1862 void trace_printk_control(bool enabled);
1863 void trace_printk_start_comm(void);
1864 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1865 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1866 
1867 /* Used from boot time tracer */
1868 extern int trace_set_options(struct trace_array *tr, char *option);
1869 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1870 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1871 					  unsigned long size, int cpu_id);
1872 extern int tracing_set_cpumask(struct trace_array *tr,
1873 				cpumask_var_t tracing_cpumask_new);
1874 
1875 
1876 #define MAX_EVENT_NAME_LEN	64
1877 
1878 extern ssize_t trace_parse_run_command(struct file *file,
1879 		const char __user *buffer, size_t count, loff_t *ppos,
1880 		int (*createfn)(const char *));
1881 
1882 extern unsigned int err_pos(char *cmd, const char *str);
1883 extern void tracing_log_err(struct trace_array *tr,
1884 			    const char *loc, const char *cmd,
1885 			    const char **errs, u8 type, u16 pos);
1886 
1887 /*
1888  * Normal trace_printk() and friends allocates special buffers
1889  * to do the manipulation, as well as saves the print formats
1890  * into sections to display. But the trace infrastructure wants
1891  * to use these without the added overhead at the price of being
1892  * a bit slower (used mainly for warnings, where we don't care
1893  * about performance). The internal_trace_puts() is for such
1894  * a purpose.
1895  */
1896 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1897 
1898 #undef FTRACE_ENTRY
1899 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1900 	extern struct trace_event_call					\
1901 	__aligned(4) event_##call;
1902 #undef FTRACE_ENTRY_DUP
1903 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1904 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1905 #undef FTRACE_ENTRY_PACKED
1906 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1907 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1908 
1909 #include "trace_entries.h"
1910 
1911 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1912 int perf_ftrace_event_register(struct trace_event_call *call,
1913 			       enum trace_reg type, void *data);
1914 #else
1915 #define perf_ftrace_event_register NULL
1916 #endif
1917 
1918 #ifdef CONFIG_FTRACE_SYSCALLS
1919 void init_ftrace_syscalls(void);
1920 const char *get_syscall_name(int syscall);
1921 #else
1922 static inline void init_ftrace_syscalls(void) { }
1923 static inline const char *get_syscall_name(int syscall)
1924 {
1925 	return NULL;
1926 }
1927 #endif
1928 
1929 #ifdef CONFIG_EVENT_TRACING
1930 void trace_event_init(void);
1931 void trace_event_eval_update(struct trace_eval_map **map, int len);
1932 /* Used from boot time tracer */
1933 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1934 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1935 #else
1936 static inline void __init trace_event_init(void) { }
1937 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1938 #endif
1939 
1940 #ifdef CONFIG_TRACER_SNAPSHOT
1941 void tracing_snapshot_instance(struct trace_array *tr);
1942 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1943 #else
1944 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1945 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1946 {
1947 	return 0;
1948 }
1949 #endif
1950 
1951 #ifdef CONFIG_PREEMPT_TRACER
1952 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1953 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1954 #else
1955 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1956 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1957 #endif
1958 #ifdef CONFIG_IRQSOFF_TRACER
1959 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1960 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1961 #else
1962 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1963 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1964 #endif
1965 
1966 /*
1967  * Reset the state of the trace_iterator so that it can read consumed data.
1968  * Normally, the trace_iterator is used for reading the data when it is not
1969  * consumed, and must retain state.
1970  */
1971 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1972 {
1973 	memset_startat(iter, 0, seq);
1974 	iter->pos = -1;
1975 }
1976 
1977 /* Check the name is good for event/group/fields */
1978 static inline bool __is_good_name(const char *name, bool hash_ok)
1979 {
1980 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
1981 		return false;
1982 	while (*++name != '\0') {
1983 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
1984 		    (!hash_ok || *name != '-'))
1985 			return false;
1986 	}
1987 	return true;
1988 }
1989 
1990 /* Check the name is good for event/group/fields */
1991 static inline bool is_good_name(const char *name)
1992 {
1993 	return __is_good_name(name, false);
1994 }
1995 
1996 /* Check the name is good for system */
1997 static inline bool is_good_system_name(const char *name)
1998 {
1999 	return __is_good_name(name, true);
2000 }
2001 
2002 /* Convert certain expected symbols into '_' when generating event names */
2003 static inline void sanitize_event_name(char *name)
2004 {
2005 	while (*name++ != '\0')
2006 		if (*name == ':' || *name == '.')
2007 			*name = '_';
2008 }
2009 
2010 /*
2011  * This is a generic way to read and write a u64 value from a file in tracefs.
2012  *
2013  * The value is stored on the variable pointed by *val. The value needs
2014  * to be at least *min and at most *max. The write is protected by an
2015  * existing *lock.
2016  */
2017 struct trace_min_max_param {
2018 	struct mutex	*lock;
2019 	u64		*val;
2020 	u64		*min;
2021 	u64		*max;
2022 };
2023 
2024 #define U64_STR_SIZE		24	/* 20 digits max */
2025 
2026 extern const struct file_operations trace_min_max_fops;
2027 
2028 #ifdef CONFIG_RV
2029 extern int rv_init_interface(void);
2030 #else
2031 static inline int rv_init_interface(void)
2032 {
2033 	return 0;
2034 }
2035 #endif
2036 
2037 #endif /* _LINUX_KERNEL_TRACE_H */
2038