xref: /openbmc/linux/kernel/trace/trace.h (revision cd99b9eb)
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 FAULT_STRING "(fault)"
117 
118 #define HIST_STACKTRACE_DEPTH	16
119 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
120 #define HIST_STACKTRACE_SKIP	5
121 
122 /*
123  * syscalls are special, and need special handling, this is why
124  * they are not included in trace_entries.h
125  */
126 struct syscall_trace_enter {
127 	struct trace_entry	ent;
128 	int			nr;
129 	unsigned long		args[];
130 };
131 
132 struct syscall_trace_exit {
133 	struct trace_entry	ent;
134 	int			nr;
135 	long			ret;
136 };
137 
138 struct kprobe_trace_entry_head {
139 	struct trace_entry	ent;
140 	unsigned long		ip;
141 };
142 
143 struct eprobe_trace_entry_head {
144 	struct trace_entry	ent;
145 };
146 
147 struct kretprobe_trace_entry_head {
148 	struct trace_entry	ent;
149 	unsigned long		func;
150 	unsigned long		ret_ip;
151 };
152 
153 struct fentry_trace_entry_head {
154 	struct trace_entry	ent;
155 	unsigned long		ip;
156 };
157 
158 struct fexit_trace_entry_head {
159 	struct trace_entry	ent;
160 	unsigned long		func;
161 	unsigned long		ret_ip;
162 };
163 
164 #define TRACE_BUF_SIZE		1024
165 
166 struct trace_array;
167 
168 /*
169  * The CPU trace array - it consists of thousands of trace entries
170  * plus some other descriptor data: (for example which task started
171  * the trace, etc.)
172  */
173 struct trace_array_cpu {
174 	atomic_t		disabled;
175 	void			*buffer_page;	/* ring buffer spare */
176 
177 	unsigned long		entries;
178 	unsigned long		saved_latency;
179 	unsigned long		critical_start;
180 	unsigned long		critical_end;
181 	unsigned long		critical_sequence;
182 	unsigned long		nice;
183 	unsigned long		policy;
184 	unsigned long		rt_priority;
185 	unsigned long		skipped_entries;
186 	u64			preempt_timestamp;
187 	pid_t			pid;
188 	kuid_t			uid;
189 	char			comm[TASK_COMM_LEN];
190 
191 #ifdef CONFIG_FUNCTION_TRACER
192 	int			ftrace_ignore_pid;
193 #endif
194 	bool			ignore_pid;
195 };
196 
197 struct tracer;
198 struct trace_option_dentry;
199 
200 struct array_buffer {
201 	struct trace_array		*tr;
202 	struct trace_buffer		*buffer;
203 	struct trace_array_cpu __percpu	*data;
204 	u64				time_start;
205 	int				cpu;
206 };
207 
208 #define TRACE_FLAGS_MAX_SIZE		32
209 
210 struct trace_options {
211 	struct tracer			*tracer;
212 	struct trace_option_dentry	*topts;
213 };
214 
215 struct trace_pid_list *trace_pid_list_alloc(void);
216 void trace_pid_list_free(struct trace_pid_list *pid_list);
217 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
218 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
219 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
220 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
221 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
222 			unsigned int *next);
223 
224 enum {
225 	TRACE_PIDS		= BIT(0),
226 	TRACE_NO_PIDS		= BIT(1),
227 };
228 
229 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
230 				    struct trace_pid_list *no_pid_list)
231 {
232 	/* Return true if the pid list in type has pids */
233 	return ((type & TRACE_PIDS) && pid_list) ||
234 		((type & TRACE_NO_PIDS) && no_pid_list);
235 }
236 
237 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
238 					 struct trace_pid_list *no_pid_list)
239 {
240 	/*
241 	 * Turning off what is in @type, return true if the "other"
242 	 * pid list, still has pids in it.
243 	 */
244 	return (!(type & TRACE_PIDS) && pid_list) ||
245 		(!(type & TRACE_NO_PIDS) && no_pid_list);
246 }
247 
248 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
249 
250 /**
251  * struct cond_snapshot - conditional snapshot data and callback
252  *
253  * The cond_snapshot structure encapsulates a callback function and
254  * data associated with the snapshot for a given tracing instance.
255  *
256  * When a snapshot is taken conditionally, by invoking
257  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
258  * passed in turn to the cond_snapshot.update() function.  That data
259  * can be compared by the update() implementation with the cond_data
260  * contained within the struct cond_snapshot instance associated with
261  * the trace_array.  Because the tr->max_lock is held throughout the
262  * update() call, the update() function can directly retrieve the
263  * cond_snapshot and cond_data associated with the per-instance
264  * snapshot associated with the trace_array.
265  *
266  * The cond_snapshot.update() implementation can save data to be
267  * associated with the snapshot if it decides to, and returns 'true'
268  * in that case, or it returns 'false' if the conditional snapshot
269  * shouldn't be taken.
270  *
271  * The cond_snapshot instance is created and associated with the
272  * user-defined cond_data by tracing_cond_snapshot_enable().
273  * Likewise, the cond_snapshot instance is destroyed and is no longer
274  * associated with the trace instance by
275  * tracing_cond_snapshot_disable().
276  *
277  * The method below is required.
278  *
279  * @update: When a conditional snapshot is invoked, the update()
280  *	callback function is invoked with the tr->max_lock held.  The
281  *	update() implementation signals whether or not to actually
282  *	take the snapshot, by returning 'true' if so, 'false' if no
283  *	snapshot should be taken.  Because the max_lock is held for
284  *	the duration of update(), the implementation is safe to
285  *	directly retrieved and save any implementation data it needs
286  *	to in association with the snapshot.
287  */
288 struct cond_snapshot {
289 	void				*cond_data;
290 	cond_update_fn_t		update;
291 };
292 
293 /*
294  * struct trace_func_repeats - used to keep track of the consecutive
295  * (on the same CPU) calls of a single function.
296  */
297 struct trace_func_repeats {
298 	unsigned long	ip;
299 	unsigned long	parent_ip;
300 	unsigned long	count;
301 	u64		ts_last_call;
302 };
303 
304 /*
305  * The trace array - an array of per-CPU trace arrays. This is the
306  * highest level data structure that individual tracers deal with.
307  * They have on/off state as well:
308  */
309 struct trace_array {
310 	struct list_head	list;
311 	char			*name;
312 	struct array_buffer	array_buffer;
313 #ifdef CONFIG_TRACER_MAX_TRACE
314 	/*
315 	 * The max_buffer is used to snapshot the trace when a maximum
316 	 * latency is reached, or when the user initiates a snapshot.
317 	 * Some tracers will use this to store a maximum trace while
318 	 * it continues examining live traces.
319 	 *
320 	 * The buffers for the max_buffer are set up the same as the array_buffer
321 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
322 	 * with the buffer of the array_buffer and the buffers are reset for
323 	 * the array_buffer so the tracing can continue.
324 	 */
325 	struct array_buffer	max_buffer;
326 	bool			allocated_snapshot;
327 #endif
328 #ifdef CONFIG_TRACER_MAX_TRACE
329 	unsigned long		max_latency;
330 #ifdef CONFIG_FSNOTIFY
331 	struct dentry		*d_max_latency;
332 	struct work_struct	fsnotify_work;
333 	struct irq_work		fsnotify_irqwork;
334 #endif
335 #endif
336 	struct trace_pid_list	__rcu *filtered_pids;
337 	struct trace_pid_list	__rcu *filtered_no_pids;
338 	/*
339 	 * max_lock is used to protect the swapping of buffers
340 	 * when taking a max snapshot. The buffers themselves are
341 	 * protected by per_cpu spinlocks. But the action of the swap
342 	 * needs its own lock.
343 	 *
344 	 * This is defined as a arch_spinlock_t in order to help
345 	 * with performance when lockdep debugging is enabled.
346 	 *
347 	 * It is also used in other places outside the update_max_tr
348 	 * so it needs to be defined outside of the
349 	 * CONFIG_TRACER_MAX_TRACE.
350 	 */
351 	arch_spinlock_t		max_lock;
352 	int			buffer_disabled;
353 #ifdef CONFIG_FTRACE_SYSCALLS
354 	int			sys_refcount_enter;
355 	int			sys_refcount_exit;
356 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
357 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
358 #endif
359 	int			stop_count;
360 	int			clock_id;
361 	int			nr_topts;
362 	bool			clear_trace;
363 	int			buffer_percent;
364 	unsigned int		n_err_log_entries;
365 	struct tracer		*current_trace;
366 	unsigned int		trace_flags;
367 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
368 	unsigned int		flags;
369 	raw_spinlock_t		start_lock;
370 	struct list_head	err_log;
371 	struct dentry		*dir;
372 	struct dentry		*options;
373 	struct dentry		*percpu_dir;
374 	struct dentry		*event_dir;
375 	struct trace_options	*topts;
376 	struct list_head	systems;
377 	struct list_head	events;
378 	struct trace_event_file *trace_marker_file;
379 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
380 	/* one per_cpu trace_pipe can be opened by only one user */
381 	cpumask_var_t		pipe_cpumask;
382 	int			ref;
383 	int			trace_ref;
384 #ifdef CONFIG_FUNCTION_TRACER
385 	struct ftrace_ops	*ops;
386 	struct trace_pid_list	__rcu *function_pids;
387 	struct trace_pid_list	__rcu *function_no_pids;
388 #ifdef CONFIG_DYNAMIC_FTRACE
389 	/* All of these are protected by the ftrace_lock */
390 	struct list_head	func_probes;
391 	struct list_head	mod_trace;
392 	struct list_head	mod_notrace;
393 #endif
394 	/* function tracing enabled */
395 	int			function_enabled;
396 #endif
397 	int			no_filter_buffering_ref;
398 	struct list_head	hist_vars;
399 #ifdef CONFIG_TRACER_SNAPSHOT
400 	struct cond_snapshot	*cond_snapshot;
401 #endif
402 	struct trace_func_repeats	__percpu *last_func_repeats;
403 };
404 
405 enum {
406 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
407 };
408 
409 extern struct list_head ftrace_trace_arrays;
410 
411 extern struct mutex trace_types_lock;
412 
413 extern int trace_array_get(struct trace_array *tr);
414 extern int tracing_check_open_get_tr(struct trace_array *tr);
415 extern struct trace_array *trace_array_find(const char *instance);
416 extern struct trace_array *trace_array_find_get(const char *instance);
417 
418 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
419 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
420 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
421 
422 extern bool trace_clock_in_ns(struct trace_array *tr);
423 
424 /*
425  * The global tracer (top) should be the first trace array added,
426  * but we check the flag anyway.
427  */
428 static inline struct trace_array *top_trace_array(void)
429 {
430 	struct trace_array *tr;
431 
432 	if (list_empty(&ftrace_trace_arrays))
433 		return NULL;
434 
435 	tr = list_entry(ftrace_trace_arrays.prev,
436 			typeof(*tr), list);
437 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
438 	return tr;
439 }
440 
441 #define FTRACE_CMP_TYPE(var, type) \
442 	__builtin_types_compatible_p(typeof(var), type *)
443 
444 #undef IF_ASSIGN
445 #define IF_ASSIGN(var, entry, etype, id)			\
446 	if (FTRACE_CMP_TYPE(var, etype)) {			\
447 		var = (typeof(var))(entry);			\
448 		WARN_ON(id != 0 && (entry)->type != id);	\
449 		break;						\
450 	}
451 
452 /* Will cause compile errors if type is not found. */
453 extern void __ftrace_bad_type(void);
454 
455 /*
456  * The trace_assign_type is a verifier that the entry type is
457  * the same as the type being assigned. To add new types simply
458  * add a line with the following format:
459  *
460  * IF_ASSIGN(var, ent, type, id);
461  *
462  *  Where "type" is the trace type that includes the trace_entry
463  *  as the "ent" item. And "id" is the trace identifier that is
464  *  used in the trace_type enum.
465  *
466  *  If the type can have more than one id, then use zero.
467  */
468 #define trace_assign_type(var, ent)					\
469 	do {								\
470 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
471 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
472 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
473 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
474 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
475 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
476 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
477 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
478 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
479 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
480 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
481 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
482 			  TRACE_MMIO_RW);				\
483 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
484 			  TRACE_MMIO_MAP);				\
485 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
486 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
487 			  TRACE_GRAPH_ENT);		\
488 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
489 			  TRACE_GRAPH_RET);		\
490 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
491 			  TRACE_FUNC_REPEATS);				\
492 		__ftrace_bad_type();					\
493 	} while (0)
494 
495 /*
496  * An option specific to a tracer. This is a boolean value.
497  * The bit is the bit index that sets its value on the
498  * flags value in struct tracer_flags.
499  */
500 struct tracer_opt {
501 	const char	*name; /* Will appear on the trace_options file */
502 	u32		bit; /* Mask assigned in val field in tracer_flags */
503 };
504 
505 /*
506  * The set of specific options for a tracer. Your tracer
507  * have to set the initial value of the flags val.
508  */
509 struct tracer_flags {
510 	u32			val;
511 	struct tracer_opt	*opts;
512 	struct tracer		*trace;
513 };
514 
515 /* Makes more easy to define a tracer opt */
516 #define TRACER_OPT(s, b)	.name = #s, .bit = b
517 
518 
519 struct trace_option_dentry {
520 	struct tracer_opt		*opt;
521 	struct tracer_flags		*flags;
522 	struct trace_array		*tr;
523 	struct dentry			*entry;
524 };
525 
526 /**
527  * struct tracer - a specific tracer and its callbacks to interact with tracefs
528  * @name: the name chosen to select it on the available_tracers file
529  * @init: called when one switches to this tracer (echo name > current_tracer)
530  * @reset: called when one switches to another tracer
531  * @start: called when tracing is unpaused (echo 1 > tracing_on)
532  * @stop: called when tracing is paused (echo 0 > tracing_on)
533  * @update_thresh: called when tracing_thresh is updated
534  * @open: called when the trace file is opened
535  * @pipe_open: called when the trace_pipe file is opened
536  * @close: called when the trace file is released
537  * @pipe_close: called when the trace_pipe file is released
538  * @read: override the default read callback on trace_pipe
539  * @splice_read: override the default splice_read callback on trace_pipe
540  * @selftest: selftest to run on boot (see trace_selftest.c)
541  * @print_headers: override the first lines that describe your columns
542  * @print_line: callback that prints a trace
543  * @set_flag: signals one of your private flags changed (trace_options file)
544  * @flags: your private flags
545  */
546 struct tracer {
547 	const char		*name;
548 	int			(*init)(struct trace_array *tr);
549 	void			(*reset)(struct trace_array *tr);
550 	void			(*start)(struct trace_array *tr);
551 	void			(*stop)(struct trace_array *tr);
552 	int			(*update_thresh)(struct trace_array *tr);
553 	void			(*open)(struct trace_iterator *iter);
554 	void			(*pipe_open)(struct trace_iterator *iter);
555 	void			(*close)(struct trace_iterator *iter);
556 	void			(*pipe_close)(struct trace_iterator *iter);
557 	ssize_t			(*read)(struct trace_iterator *iter,
558 					struct file *filp, char __user *ubuf,
559 					size_t cnt, loff_t *ppos);
560 	ssize_t			(*splice_read)(struct trace_iterator *iter,
561 					       struct file *filp,
562 					       loff_t *ppos,
563 					       struct pipe_inode_info *pipe,
564 					       size_t len,
565 					       unsigned int flags);
566 #ifdef CONFIG_FTRACE_STARTUP_TEST
567 	int			(*selftest)(struct tracer *trace,
568 					    struct trace_array *tr);
569 #endif
570 	void			(*print_header)(struct seq_file *m);
571 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
572 	/* If you handled the flag setting, return 0 */
573 	int			(*set_flag)(struct trace_array *tr,
574 					    u32 old_flags, u32 bit, int set);
575 	/* Return 0 if OK with change, else return non-zero */
576 	int			(*flag_changed)(struct trace_array *tr,
577 						u32 mask, int set);
578 	struct tracer		*next;
579 	struct tracer_flags	*flags;
580 	int			enabled;
581 	bool			print_max;
582 	bool			allow_instances;
583 #ifdef CONFIG_TRACER_MAX_TRACE
584 	bool			use_max_tr;
585 #endif
586 	/* True if tracer cannot be enabled in kernel param */
587 	bool			noboot;
588 };
589 
590 static inline struct ring_buffer_iter *
591 trace_buffer_iter(struct trace_iterator *iter, int cpu)
592 {
593 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
594 }
595 
596 int tracer_init(struct tracer *t, struct trace_array *tr);
597 int tracing_is_enabled(void);
598 void tracing_reset_online_cpus(struct array_buffer *buf);
599 void tracing_reset_current(int cpu);
600 void tracing_reset_all_online_cpus(void);
601 void tracing_reset_all_online_cpus_unlocked(void);
602 int tracing_open_generic(struct inode *inode, struct file *filp);
603 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
604 bool tracing_is_disabled(void);
605 bool tracer_tracing_is_on(struct trace_array *tr);
606 void tracer_tracing_on(struct trace_array *tr);
607 void tracer_tracing_off(struct trace_array *tr);
608 struct dentry *trace_create_file(const char *name,
609 				 umode_t mode,
610 				 struct dentry *parent,
611 				 void *data,
612 				 const struct file_operations *fops);
613 
614 int tracing_init_dentry(void);
615 
616 struct ring_buffer_event;
617 
618 struct ring_buffer_event *
619 trace_buffer_lock_reserve(struct trace_buffer *buffer,
620 			  int type,
621 			  unsigned long len,
622 			  unsigned int trace_ctx);
623 
624 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
625 						struct trace_array_cpu *data);
626 
627 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
628 					  int *ent_cpu, u64 *ent_ts);
629 
630 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
631 					struct ring_buffer_event *event);
632 
633 bool trace_is_tracepoint_string(const char *str);
634 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
635 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
636 			 va_list ap) __printf(2, 0);
637 char *trace_iter_expand_format(struct trace_iterator *iter);
638 
639 int trace_empty(struct trace_iterator *iter);
640 
641 void *trace_find_next_entry_inc(struct trace_iterator *iter);
642 
643 void trace_init_global_iter(struct trace_iterator *iter);
644 
645 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
646 
647 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
648 unsigned long trace_total_entries(struct trace_array *tr);
649 
650 void trace_function(struct trace_array *tr,
651 		    unsigned long ip,
652 		    unsigned long parent_ip,
653 		    unsigned int trace_ctx);
654 void trace_graph_function(struct trace_array *tr,
655 		    unsigned long ip,
656 		    unsigned long parent_ip,
657 		    unsigned int trace_ctx);
658 void trace_latency_header(struct seq_file *m);
659 void trace_default_header(struct seq_file *m);
660 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
661 
662 void trace_graph_return(struct ftrace_graph_ret *trace);
663 int trace_graph_entry(struct ftrace_graph_ent *trace);
664 void set_graph_array(struct trace_array *tr);
665 
666 void tracing_start_cmdline_record(void);
667 void tracing_stop_cmdline_record(void);
668 void tracing_start_tgid_record(void);
669 void tracing_stop_tgid_record(void);
670 
671 int register_tracer(struct tracer *type);
672 int is_tracing_stopped(void);
673 
674 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
675 
676 extern cpumask_var_t __read_mostly tracing_buffer_mask;
677 
678 #define for_each_tracing_cpu(cpu)	\
679 	for_each_cpu(cpu, tracing_buffer_mask)
680 
681 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
682 
683 extern unsigned long tracing_thresh;
684 
685 /* PID filtering */
686 
687 extern int pid_max;
688 
689 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
690 			     pid_t search_pid);
691 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
692 			    struct trace_pid_list *filtered_no_pids,
693 			    struct task_struct *task);
694 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
695 				  struct task_struct *self,
696 				  struct task_struct *task);
697 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
698 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
699 int trace_pid_show(struct seq_file *m, void *v);
700 void trace_free_pid_list(struct trace_pid_list *pid_list);
701 int trace_pid_write(struct trace_pid_list *filtered_pids,
702 		    struct trace_pid_list **new_pid_list,
703 		    const char __user *ubuf, size_t cnt);
704 
705 #ifdef CONFIG_TRACER_MAX_TRACE
706 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
707 		   void *cond_data);
708 void update_max_tr_single(struct trace_array *tr,
709 			  struct task_struct *tsk, int cpu);
710 
711 #ifdef CONFIG_FSNOTIFY
712 #define LATENCY_FS_NOTIFY
713 #endif
714 #endif /* CONFIG_TRACER_MAX_TRACE */
715 
716 #ifdef LATENCY_FS_NOTIFY
717 void latency_fsnotify(struct trace_array *tr);
718 #else
719 static inline void latency_fsnotify(struct trace_array *tr) { }
720 #endif
721 
722 #ifdef CONFIG_STACKTRACE
723 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
724 #else
725 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
726 				 int skip)
727 {
728 }
729 #endif /* CONFIG_STACKTRACE */
730 
731 void trace_last_func_repeats(struct trace_array *tr,
732 			     struct trace_func_repeats *last_info,
733 			     unsigned int trace_ctx);
734 
735 extern u64 ftrace_now(int cpu);
736 
737 extern void trace_find_cmdline(int pid, char comm[]);
738 extern int trace_find_tgid(int pid);
739 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
740 
741 #ifdef CONFIG_DYNAMIC_FTRACE
742 extern unsigned long ftrace_update_tot_cnt;
743 extern unsigned long ftrace_number_of_pages;
744 extern unsigned long ftrace_number_of_groups;
745 void ftrace_init_trace_array(struct trace_array *tr);
746 #else
747 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
748 #endif
749 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
750 extern int DYN_FTRACE_TEST_NAME(void);
751 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
752 extern int DYN_FTRACE_TEST_NAME2(void);
753 
754 extern bool ring_buffer_expanded;
755 extern bool tracing_selftest_disabled;
756 
757 #ifdef CONFIG_FTRACE_STARTUP_TEST
758 extern void __init disable_tracing_selftest(const char *reason);
759 
760 extern int trace_selftest_startup_function(struct tracer *trace,
761 					   struct trace_array *tr);
762 extern int trace_selftest_startup_function_graph(struct tracer *trace,
763 						 struct trace_array *tr);
764 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
765 					  struct trace_array *tr);
766 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
767 					     struct trace_array *tr);
768 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
769 						 struct trace_array *tr);
770 extern int trace_selftest_startup_wakeup(struct tracer *trace,
771 					 struct trace_array *tr);
772 extern int trace_selftest_startup_nop(struct tracer *trace,
773 					 struct trace_array *tr);
774 extern int trace_selftest_startup_branch(struct tracer *trace,
775 					 struct trace_array *tr);
776 /*
777  * Tracer data references selftest functions that only occur
778  * on boot up. These can be __init functions. Thus, when selftests
779  * are enabled, then the tracers need to reference __init functions.
780  */
781 #define __tracer_data		__refdata
782 #else
783 static inline void __init disable_tracing_selftest(const char *reason)
784 {
785 }
786 /* Tracers are seldom changed. Optimize when selftests are disabled. */
787 #define __tracer_data		__read_mostly
788 #endif /* CONFIG_FTRACE_STARTUP_TEST */
789 
790 extern void *head_page(struct trace_array_cpu *data);
791 extern unsigned long long ns2usecs(u64 nsec);
792 extern int
793 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
794 extern int
795 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
796 extern int
797 trace_array_vprintk(struct trace_array *tr,
798 		    unsigned long ip, const char *fmt, va_list args);
799 int trace_array_printk_buf(struct trace_buffer *buffer,
800 			   unsigned long ip, const char *fmt, ...);
801 void trace_printk_seq(struct trace_seq *s);
802 enum print_line_t print_trace_line(struct trace_iterator *iter);
803 
804 extern char trace_find_mark(unsigned long long duration);
805 
806 struct ftrace_hash;
807 
808 struct ftrace_mod_load {
809 	struct list_head	list;
810 	char			*func;
811 	char			*module;
812 	int			 enable;
813 };
814 
815 enum {
816 	FTRACE_HASH_FL_MOD	= (1 << 0),
817 };
818 
819 struct ftrace_hash {
820 	unsigned long		size_bits;
821 	struct hlist_head	*buckets;
822 	unsigned long		count;
823 	unsigned long		flags;
824 	struct rcu_head		rcu;
825 };
826 
827 struct ftrace_func_entry *
828 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
829 
830 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
831 {
832 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
833 }
834 
835 /* Standard output formatting function used for function return traces */
836 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
837 
838 /* Flag options */
839 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
840 #define TRACE_GRAPH_PRINT_CPU           0x2
841 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
842 #define TRACE_GRAPH_PRINT_PROC          0x8
843 #define TRACE_GRAPH_PRINT_DURATION      0x10
844 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
845 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
846 #define TRACE_GRAPH_PRINT_IRQS          0x80
847 #define TRACE_GRAPH_PRINT_TAIL          0x100
848 #define TRACE_GRAPH_SLEEP_TIME          0x200
849 #define TRACE_GRAPH_GRAPH_TIME          0x400
850 #define TRACE_GRAPH_PRINT_RETVAL        0x800
851 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
852 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
853 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
854 
855 extern void ftrace_graph_sleep_time_control(bool enable);
856 
857 #ifdef CONFIG_FUNCTION_PROFILER
858 extern void ftrace_graph_graph_time_control(bool enable);
859 #else
860 static inline void ftrace_graph_graph_time_control(bool enable) { }
861 #endif
862 
863 extern enum print_line_t
864 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
865 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
866 extern void
867 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
868 extern void graph_trace_open(struct trace_iterator *iter);
869 extern void graph_trace_close(struct trace_iterator *iter);
870 extern int __trace_graph_entry(struct trace_array *tr,
871 			       struct ftrace_graph_ent *trace,
872 			       unsigned int trace_ctx);
873 extern void __trace_graph_return(struct trace_array *tr,
874 				 struct ftrace_graph_ret *trace,
875 				 unsigned int trace_ctx);
876 
877 #ifdef CONFIG_DYNAMIC_FTRACE
878 extern struct ftrace_hash __rcu *ftrace_graph_hash;
879 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
880 
881 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
882 {
883 	unsigned long addr = trace->func;
884 	int ret = 0;
885 	struct ftrace_hash *hash;
886 
887 	preempt_disable_notrace();
888 
889 	/*
890 	 * Have to open code "rcu_dereference_sched()" because the
891 	 * function graph tracer can be called when RCU is not
892 	 * "watching".
893 	 * Protected with schedule_on_each_cpu(ftrace_sync)
894 	 */
895 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
896 
897 	if (ftrace_hash_empty(hash)) {
898 		ret = 1;
899 		goto out;
900 	}
901 
902 	if (ftrace_lookup_ip(hash, addr)) {
903 
904 		/*
905 		 * This needs to be cleared on the return functions
906 		 * when the depth is zero.
907 		 */
908 		trace_recursion_set(TRACE_GRAPH_BIT);
909 		trace_recursion_set_depth(trace->depth);
910 
911 		/*
912 		 * If no irqs are to be traced, but a set_graph_function
913 		 * is set, and called by an interrupt handler, we still
914 		 * want to trace it.
915 		 */
916 		if (in_hardirq())
917 			trace_recursion_set(TRACE_IRQ_BIT);
918 		else
919 			trace_recursion_clear(TRACE_IRQ_BIT);
920 		ret = 1;
921 	}
922 
923 out:
924 	preempt_enable_notrace();
925 	return ret;
926 }
927 
928 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
929 {
930 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
931 	    trace->depth == trace_recursion_depth())
932 		trace_recursion_clear(TRACE_GRAPH_BIT);
933 }
934 
935 static inline int ftrace_graph_notrace_addr(unsigned long addr)
936 {
937 	int ret = 0;
938 	struct ftrace_hash *notrace_hash;
939 
940 	preempt_disable_notrace();
941 
942 	/*
943 	 * Have to open code "rcu_dereference_sched()" because the
944 	 * function graph tracer can be called when RCU is not
945 	 * "watching".
946 	 * Protected with schedule_on_each_cpu(ftrace_sync)
947 	 */
948 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
949 						 !preemptible());
950 
951 	if (ftrace_lookup_ip(notrace_hash, addr))
952 		ret = 1;
953 
954 	preempt_enable_notrace();
955 	return ret;
956 }
957 #else
958 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
959 {
960 	return 1;
961 }
962 
963 static inline int ftrace_graph_notrace_addr(unsigned long addr)
964 {
965 	return 0;
966 }
967 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
968 { }
969 #endif /* CONFIG_DYNAMIC_FTRACE */
970 
971 extern unsigned int fgraph_max_depth;
972 
973 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
974 {
975 	/* trace it when it is-nested-in or is a function enabled. */
976 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
977 		 ftrace_graph_addr(trace)) ||
978 		(trace->depth < 0) ||
979 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
980 }
981 
982 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
983 static inline enum print_line_t
984 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
985 {
986 	return TRACE_TYPE_UNHANDLED;
987 }
988 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
989 
990 extern struct list_head ftrace_pids;
991 
992 #ifdef CONFIG_FUNCTION_TRACER
993 
994 #define FTRACE_PID_IGNORE	-1
995 #define FTRACE_PID_TRACE	-2
996 
997 struct ftrace_func_command {
998 	struct list_head	list;
999 	char			*name;
1000 	int			(*func)(struct trace_array *tr,
1001 					struct ftrace_hash *hash,
1002 					char *func, char *cmd,
1003 					char *params, int enable);
1004 };
1005 extern bool ftrace_filter_param __initdata;
1006 static inline int ftrace_trace_task(struct trace_array *tr)
1007 {
1008 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1009 		FTRACE_PID_IGNORE;
1010 }
1011 extern int ftrace_is_dead(void);
1012 int ftrace_create_function_files(struct trace_array *tr,
1013 				 struct dentry *parent);
1014 void ftrace_destroy_function_files(struct trace_array *tr);
1015 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1016 void ftrace_free_ftrace_ops(struct trace_array *tr);
1017 void ftrace_init_global_array_ops(struct trace_array *tr);
1018 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1019 void ftrace_reset_array_ops(struct trace_array *tr);
1020 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1021 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1022 				  struct dentry *d_tracer);
1023 void ftrace_clear_pids(struct trace_array *tr);
1024 int init_function_trace(void);
1025 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1026 #else
1027 static inline int ftrace_trace_task(struct trace_array *tr)
1028 {
1029 	return 1;
1030 }
1031 static inline int ftrace_is_dead(void) { return 0; }
1032 static inline int
1033 ftrace_create_function_files(struct trace_array *tr,
1034 			     struct dentry *parent)
1035 {
1036 	return 0;
1037 }
1038 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1039 {
1040 	return 0;
1041 }
1042 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1043 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1044 static inline __init void
1045 ftrace_init_global_array_ops(struct trace_array *tr) { }
1046 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1047 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1048 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1049 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1050 static inline int init_function_trace(void) { return 0; }
1051 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1052 /* ftace_func_t type is not defined, use macro instead of static inline */
1053 #define ftrace_init_array_ops(tr, func) do { } while (0)
1054 #endif /* CONFIG_FUNCTION_TRACER */
1055 
1056 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1057 
1058 struct ftrace_probe_ops {
1059 	void			(*func)(unsigned long ip,
1060 					unsigned long parent_ip,
1061 					struct trace_array *tr,
1062 					struct ftrace_probe_ops *ops,
1063 					void *data);
1064 	int			(*init)(struct ftrace_probe_ops *ops,
1065 					struct trace_array *tr,
1066 					unsigned long ip, void *init_data,
1067 					void **data);
1068 	void			(*free)(struct ftrace_probe_ops *ops,
1069 					struct trace_array *tr,
1070 					unsigned long ip, void *data);
1071 	int			(*print)(struct seq_file *m,
1072 					 unsigned long ip,
1073 					 struct ftrace_probe_ops *ops,
1074 					 void *data);
1075 };
1076 
1077 struct ftrace_func_mapper;
1078 typedef int (*ftrace_mapper_func)(void *data);
1079 
1080 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1081 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1082 					   unsigned long ip);
1083 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1084 			       unsigned long ip, void *data);
1085 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1086 				   unsigned long ip);
1087 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1088 			     ftrace_mapper_func free_func);
1089 
1090 extern int
1091 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1092 			       struct ftrace_probe_ops *ops, void *data);
1093 extern int
1094 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1095 				      struct ftrace_probe_ops *ops);
1096 extern void clear_ftrace_function_probes(struct trace_array *tr);
1097 
1098 int register_ftrace_command(struct ftrace_func_command *cmd);
1099 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1100 
1101 void ftrace_create_filter_files(struct ftrace_ops *ops,
1102 				struct dentry *parent);
1103 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1104 
1105 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1106 			     int len, int reset);
1107 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1108 			      int len, int reset);
1109 #else
1110 struct ftrace_func_command;
1111 
1112 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1113 {
1114 	return -EINVAL;
1115 }
1116 static inline __init int unregister_ftrace_command(char *cmd_name)
1117 {
1118 	return -EINVAL;
1119 }
1120 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1121 {
1122 }
1123 
1124 /*
1125  * The ops parameter passed in is usually undefined.
1126  * This must be a macro.
1127  */
1128 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1129 #define ftrace_destroy_filter_files(ops) do { } while (0)
1130 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1131 
1132 bool ftrace_event_is_function(struct trace_event_call *call);
1133 
1134 /*
1135  * struct trace_parser - servers for reading the user input separated by spaces
1136  * @cont: set if the input is not complete - no final space char was found
1137  * @buffer: holds the parsed user input
1138  * @idx: user input length
1139  * @size: buffer size
1140  */
1141 struct trace_parser {
1142 	bool		cont;
1143 	char		*buffer;
1144 	unsigned	idx;
1145 	unsigned	size;
1146 };
1147 
1148 static inline bool trace_parser_loaded(struct trace_parser *parser)
1149 {
1150 	return (parser->idx != 0);
1151 }
1152 
1153 static inline bool trace_parser_cont(struct trace_parser *parser)
1154 {
1155 	return parser->cont;
1156 }
1157 
1158 static inline void trace_parser_clear(struct trace_parser *parser)
1159 {
1160 	parser->cont = false;
1161 	parser->idx = 0;
1162 }
1163 
1164 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1165 extern void trace_parser_put(struct trace_parser *parser);
1166 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1167 	size_t cnt, loff_t *ppos);
1168 
1169 /*
1170  * Only create function graph options if function graph is configured.
1171  */
1172 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1173 # define FGRAPH_FLAGS						\
1174 		C(DISPLAY_GRAPH,	"display-graph"),
1175 #else
1176 # define FGRAPH_FLAGS
1177 #endif
1178 
1179 #ifdef CONFIG_BRANCH_TRACER
1180 # define BRANCH_FLAGS					\
1181 		C(BRANCH,		"branch"),
1182 #else
1183 # define BRANCH_FLAGS
1184 #endif
1185 
1186 #ifdef CONFIG_FUNCTION_TRACER
1187 # define FUNCTION_FLAGS						\
1188 		C(FUNCTION,		"function-trace"),	\
1189 		C(FUNC_FORK,		"function-fork"),
1190 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1191 #else
1192 # define FUNCTION_FLAGS
1193 # define FUNCTION_DEFAULT_FLAGS		0UL
1194 # define TRACE_ITER_FUNC_FORK		0UL
1195 #endif
1196 
1197 #ifdef CONFIG_STACKTRACE
1198 # define STACK_FLAGS				\
1199 		C(STACKTRACE,		"stacktrace"),
1200 #else
1201 # define STACK_FLAGS
1202 #endif
1203 
1204 /*
1205  * trace_iterator_flags is an enumeration that defines bit
1206  * positions into trace_flags that controls the output.
1207  *
1208  * NOTE: These bits must match the trace_options array in
1209  *       trace.c (this macro guarantees it).
1210  */
1211 #define TRACE_FLAGS						\
1212 		C(PRINT_PARENT,		"print-parent"),	\
1213 		C(SYM_OFFSET,		"sym-offset"),		\
1214 		C(SYM_ADDR,		"sym-addr"),		\
1215 		C(VERBOSE,		"verbose"),		\
1216 		C(RAW,			"raw"),			\
1217 		C(HEX,			"hex"),			\
1218 		C(BIN,			"bin"),			\
1219 		C(BLOCK,		"block"),		\
1220 		C(FIELDS,		"fields"),		\
1221 		C(PRINTK,		"trace_printk"),	\
1222 		C(ANNOTATE,		"annotate"),		\
1223 		C(USERSTACKTRACE,	"userstacktrace"),	\
1224 		C(SYM_USEROBJ,		"sym-userobj"),		\
1225 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1226 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1227 		C(LATENCY_FMT,		"latency-format"),	\
1228 		C(RECORD_CMD,		"record-cmd"),		\
1229 		C(RECORD_TGID,		"record-tgid"),		\
1230 		C(OVERWRITE,		"overwrite"),		\
1231 		C(STOP_ON_FREE,		"disable_on_free"),	\
1232 		C(IRQ_INFO,		"irq-info"),		\
1233 		C(MARKERS,		"markers"),		\
1234 		C(EVENT_FORK,		"event-fork"),		\
1235 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1236 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1237 		FUNCTION_FLAGS					\
1238 		FGRAPH_FLAGS					\
1239 		STACK_FLAGS					\
1240 		BRANCH_FLAGS
1241 
1242 /*
1243  * By defining C, we can make TRACE_FLAGS a list of bit names
1244  * that will define the bits for the flag masks.
1245  */
1246 #undef C
1247 #define C(a, b) TRACE_ITER_##a##_BIT
1248 
1249 enum trace_iterator_bits {
1250 	TRACE_FLAGS
1251 	/* Make sure we don't go more than we have bits for */
1252 	TRACE_ITER_LAST_BIT
1253 };
1254 
1255 /*
1256  * By redefining C, we can make TRACE_FLAGS a list of masks that
1257  * use the bits as defined above.
1258  */
1259 #undef C
1260 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1261 
1262 enum trace_iterator_flags { TRACE_FLAGS };
1263 
1264 /*
1265  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1266  * control the output of kernel symbols.
1267  */
1268 #define TRACE_ITER_SYM_MASK \
1269 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1270 
1271 extern struct tracer nop_trace;
1272 
1273 #ifdef CONFIG_BRANCH_TRACER
1274 extern int enable_branch_tracing(struct trace_array *tr);
1275 extern void disable_branch_tracing(void);
1276 static inline int trace_branch_enable(struct trace_array *tr)
1277 {
1278 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1279 		return enable_branch_tracing(tr);
1280 	return 0;
1281 }
1282 static inline void trace_branch_disable(void)
1283 {
1284 	/* due to races, always disable */
1285 	disable_branch_tracing();
1286 }
1287 #else
1288 static inline int trace_branch_enable(struct trace_array *tr)
1289 {
1290 	return 0;
1291 }
1292 static inline void trace_branch_disable(void)
1293 {
1294 }
1295 #endif /* CONFIG_BRANCH_TRACER */
1296 
1297 /* set ring buffers to default size if not already done so */
1298 int tracing_update_buffers(void);
1299 
1300 union trace_synth_field {
1301 	u8				as_u8;
1302 	u16				as_u16;
1303 	u32				as_u32;
1304 	u64				as_u64;
1305 	struct trace_dynamic_info	as_dynamic;
1306 };
1307 
1308 struct ftrace_event_field {
1309 	struct list_head	link;
1310 	const char		*name;
1311 	const char		*type;
1312 	int			filter_type;
1313 	int			offset;
1314 	int			size;
1315 	int			is_signed;
1316 	int			len;
1317 };
1318 
1319 struct prog_entry;
1320 
1321 struct event_filter {
1322 	struct prog_entry __rcu	*prog;
1323 	char			*filter_string;
1324 };
1325 
1326 struct event_subsystem {
1327 	struct list_head	list;
1328 	const char		*name;
1329 	struct event_filter	*filter;
1330 	int			ref_count;
1331 };
1332 
1333 struct trace_subsystem_dir {
1334 	struct list_head		list;
1335 	struct event_subsystem		*subsystem;
1336 	struct trace_array		*tr;
1337 	struct dentry			*entry;
1338 	int				ref_count;
1339 	int				nr_events;
1340 };
1341 
1342 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1343 				     struct trace_buffer *buffer,
1344 				     struct ring_buffer_event *event);
1345 
1346 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1347 				     struct trace_buffer *buffer,
1348 				     struct ring_buffer_event *event,
1349 				     unsigned int trcace_ctx,
1350 				     struct pt_regs *regs);
1351 
1352 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1353 					      struct trace_buffer *buffer,
1354 					      struct ring_buffer_event *event,
1355 					      unsigned int trace_ctx)
1356 {
1357 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1358 }
1359 
1360 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1361 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1362 void trace_buffered_event_disable(void);
1363 void trace_buffered_event_enable(void);
1364 
1365 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1366 
1367 static inline void
1368 __trace_event_discard_commit(struct trace_buffer *buffer,
1369 			     struct ring_buffer_event *event)
1370 {
1371 	if (this_cpu_read(trace_buffered_event) == event) {
1372 		/* Simply release the temp buffer and enable preemption */
1373 		this_cpu_dec(trace_buffered_event_cnt);
1374 		preempt_enable_notrace();
1375 		return;
1376 	}
1377 	/* ring_buffer_discard_commit() enables preemption */
1378 	ring_buffer_discard_commit(buffer, event);
1379 }
1380 
1381 /*
1382  * Helper function for event_trigger_unlock_commit{_regs}().
1383  * If there are event triggers attached to this event that requires
1384  * filtering against its fields, then they will be called as the
1385  * entry already holds the field information of the current event.
1386  *
1387  * It also checks if the event should be discarded or not.
1388  * It is to be discarded if the event is soft disabled and the
1389  * event was only recorded to process triggers, or if the event
1390  * filter is active and this event did not match the filters.
1391  *
1392  * Returns true if the event is discarded, false otherwise.
1393  */
1394 static inline bool
1395 __event_trigger_test_discard(struct trace_event_file *file,
1396 			     struct trace_buffer *buffer,
1397 			     struct ring_buffer_event *event,
1398 			     void *entry,
1399 			     enum event_trigger_type *tt)
1400 {
1401 	unsigned long eflags = file->flags;
1402 
1403 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1404 		*tt = event_triggers_call(file, buffer, entry, event);
1405 
1406 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1407 				    EVENT_FILE_FL_FILTERED |
1408 				    EVENT_FILE_FL_PID_FILTER))))
1409 		return false;
1410 
1411 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1412 		goto discard;
1413 
1414 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1415 	    !filter_match_preds(file->filter, entry))
1416 		goto discard;
1417 
1418 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1419 	    trace_event_ignore_this_pid(file))
1420 		goto discard;
1421 
1422 	return false;
1423  discard:
1424 	__trace_event_discard_commit(buffer, event);
1425 	return true;
1426 }
1427 
1428 /**
1429  * event_trigger_unlock_commit - handle triggers and finish event commit
1430  * @file: The file pointer associated with the event
1431  * @buffer: The ring buffer that the event is being written to
1432  * @event: The event meta data in the ring buffer
1433  * @entry: The event itself
1434  * @trace_ctx: The tracing context flags.
1435  *
1436  * This is a helper function to handle triggers that require data
1437  * from the event itself. It also tests the event against filters and
1438  * if the event is soft disabled and should be discarded.
1439  */
1440 static inline void
1441 event_trigger_unlock_commit(struct trace_event_file *file,
1442 			    struct trace_buffer *buffer,
1443 			    struct ring_buffer_event *event,
1444 			    void *entry, unsigned int trace_ctx)
1445 {
1446 	enum event_trigger_type tt = ETT_NONE;
1447 
1448 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1449 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1450 
1451 	if (tt)
1452 		event_triggers_post_call(file, tt);
1453 }
1454 
1455 #define FILTER_PRED_INVALID	((unsigned short)-1)
1456 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1457 #define FILTER_PRED_FOLD	(1 << 15)
1458 
1459 /*
1460  * The max preds is the size of unsigned short with
1461  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1462  * and FOLD flags. The other is reserved.
1463  *
1464  * 2^14 preds is way more than enough.
1465  */
1466 #define MAX_FILTER_PRED		16384
1467 
1468 struct filter_pred;
1469 struct regex;
1470 
1471 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1472 
1473 enum regex_type {
1474 	MATCH_FULL = 0,
1475 	MATCH_FRONT_ONLY,
1476 	MATCH_MIDDLE_ONLY,
1477 	MATCH_END_ONLY,
1478 	MATCH_GLOB,
1479 	MATCH_INDEX,
1480 };
1481 
1482 struct regex {
1483 	char			pattern[MAX_FILTER_STR_VAL];
1484 	int			len;
1485 	int			field_len;
1486 	regex_match_func	match;
1487 };
1488 
1489 static inline bool is_string_field(struct ftrace_event_field *field)
1490 {
1491 	return field->filter_type == FILTER_DYN_STRING ||
1492 	       field->filter_type == FILTER_RDYN_STRING ||
1493 	       field->filter_type == FILTER_STATIC_STRING ||
1494 	       field->filter_type == FILTER_PTR_STRING ||
1495 	       field->filter_type == FILTER_COMM;
1496 }
1497 
1498 static inline bool is_function_field(struct ftrace_event_field *field)
1499 {
1500 	return field->filter_type == FILTER_TRACE_FN;
1501 }
1502 
1503 extern enum regex_type
1504 filter_parse_regex(char *buff, int len, char **search, int *not);
1505 extern void print_event_filter(struct trace_event_file *file,
1506 			       struct trace_seq *s);
1507 extern int apply_event_filter(struct trace_event_file *file,
1508 			      char *filter_string);
1509 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1510 					char *filter_string);
1511 extern void print_subsystem_event_filter(struct event_subsystem *system,
1512 					 struct trace_seq *s);
1513 extern int filter_assign_type(const char *type);
1514 extern int create_event_filter(struct trace_array *tr,
1515 			       struct trace_event_call *call,
1516 			       char *filter_str, bool set_str,
1517 			       struct event_filter **filterp);
1518 extern void free_event_filter(struct event_filter *filter);
1519 
1520 struct ftrace_event_field *
1521 trace_find_event_field(struct trace_event_call *call, char *name);
1522 
1523 extern void trace_event_enable_cmd_record(bool enable);
1524 extern void trace_event_enable_tgid_record(bool enable);
1525 
1526 extern int event_trace_init(void);
1527 extern int init_events(void);
1528 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1529 extern int event_trace_del_tracer(struct trace_array *tr);
1530 extern void __trace_early_add_events(struct trace_array *tr);
1531 
1532 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1533 						  const char *system,
1534 						  const char *event);
1535 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1536 						const char *system,
1537 						const char *event);
1538 
1539 static inline void *event_file_data(struct file *filp)
1540 {
1541 	return READ_ONCE(file_inode(filp)->i_private);
1542 }
1543 
1544 extern struct mutex event_mutex;
1545 extern struct list_head ftrace_events;
1546 
1547 extern const struct file_operations event_trigger_fops;
1548 extern const struct file_operations event_hist_fops;
1549 extern const struct file_operations event_hist_debug_fops;
1550 extern const struct file_operations event_inject_fops;
1551 
1552 #ifdef CONFIG_HIST_TRIGGERS
1553 extern int register_trigger_hist_cmd(void);
1554 extern int register_trigger_hist_enable_disable_cmds(void);
1555 #else
1556 static inline int register_trigger_hist_cmd(void) { return 0; }
1557 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1558 #endif
1559 
1560 extern int register_trigger_cmds(void);
1561 extern void clear_event_triggers(struct trace_array *tr);
1562 
1563 enum {
1564 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1565 };
1566 
1567 struct event_trigger_data {
1568 	unsigned long			count;
1569 	int				ref;
1570 	int				flags;
1571 	struct event_trigger_ops	*ops;
1572 	struct event_command		*cmd_ops;
1573 	struct event_filter __rcu	*filter;
1574 	char				*filter_str;
1575 	void				*private_data;
1576 	bool				paused;
1577 	bool				paused_tmp;
1578 	struct list_head		list;
1579 	char				*name;
1580 	struct list_head		named_list;
1581 	struct event_trigger_data	*named_data;
1582 };
1583 
1584 /* Avoid typos */
1585 #define ENABLE_EVENT_STR	"enable_event"
1586 #define DISABLE_EVENT_STR	"disable_event"
1587 #define ENABLE_HIST_STR		"enable_hist"
1588 #define DISABLE_HIST_STR	"disable_hist"
1589 
1590 struct enable_trigger_data {
1591 	struct trace_event_file		*file;
1592 	bool				enable;
1593 	bool				hist;
1594 };
1595 
1596 extern int event_enable_trigger_print(struct seq_file *m,
1597 				      struct event_trigger_data *data);
1598 extern void event_enable_trigger_free(struct event_trigger_data *data);
1599 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1600 				      struct trace_event_file *file,
1601 				      char *glob, char *cmd,
1602 				      char *param_and_filter);
1603 extern int event_enable_register_trigger(char *glob,
1604 					 struct event_trigger_data *data,
1605 					 struct trace_event_file *file);
1606 extern void event_enable_unregister_trigger(char *glob,
1607 					    struct event_trigger_data *test,
1608 					    struct trace_event_file *file);
1609 extern void trigger_data_free(struct event_trigger_data *data);
1610 extern int event_trigger_init(struct event_trigger_data *data);
1611 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1612 					      int trigger_enable);
1613 extern void update_cond_flag(struct trace_event_file *file);
1614 extern int set_trigger_filter(char *filter_str,
1615 			      struct event_trigger_data *trigger_data,
1616 			      struct trace_event_file *file);
1617 extern struct event_trigger_data *find_named_trigger(const char *name);
1618 extern bool is_named_trigger(struct event_trigger_data *test);
1619 extern int save_named_trigger(const char *name,
1620 			      struct event_trigger_data *data);
1621 extern void del_named_trigger(struct event_trigger_data *data);
1622 extern void pause_named_trigger(struct event_trigger_data *data);
1623 extern void unpause_named_trigger(struct event_trigger_data *data);
1624 extern void set_named_trigger_data(struct event_trigger_data *data,
1625 				   struct event_trigger_data *named_data);
1626 extern struct event_trigger_data *
1627 get_named_trigger_data(struct event_trigger_data *data);
1628 extern int register_event_command(struct event_command *cmd);
1629 extern int unregister_event_command(struct event_command *cmd);
1630 extern int register_trigger_hist_enable_disable_cmds(void);
1631 extern bool event_trigger_check_remove(const char *glob);
1632 extern bool event_trigger_empty_param(const char *param);
1633 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1634 					 char **filter, bool param_required);
1635 extern struct event_trigger_data *
1636 event_trigger_alloc(struct event_command *cmd_ops,
1637 		    char *cmd,
1638 		    char *param,
1639 		    void *private_data);
1640 extern int event_trigger_parse_num(char *trigger,
1641 				   struct event_trigger_data *trigger_data);
1642 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1643 				    struct trace_event_file *file,
1644 				    char *param,
1645 				    struct event_trigger_data *trigger_data);
1646 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1647 				       struct event_trigger_data *trigger_data);
1648 extern int event_trigger_register(struct event_command *cmd_ops,
1649 				  struct trace_event_file *file,
1650 				  char *glob,
1651 				  struct event_trigger_data *trigger_data);
1652 extern void event_trigger_unregister(struct event_command *cmd_ops,
1653 				     struct trace_event_file *file,
1654 				     char *glob,
1655 				     struct event_trigger_data *trigger_data);
1656 
1657 /**
1658  * struct event_trigger_ops - callbacks for trace event triggers
1659  *
1660  * The methods in this structure provide per-event trigger hooks for
1661  * various trigger operations.
1662  *
1663  * The @init and @free methods are used during trigger setup and
1664  * teardown, typically called from an event_command's @parse()
1665  * function implementation.
1666  *
1667  * The @print method is used to print the trigger spec.
1668  *
1669  * The @trigger method is the function that actually implements the
1670  * trigger and is called in the context of the triggering event
1671  * whenever that event occurs.
1672  *
1673  * All the methods below, except for @init() and @free(), must be
1674  * implemented.
1675  *
1676  * @trigger: The trigger 'probe' function called when the triggering
1677  *	event occurs.  The data passed into this callback is the data
1678  *	that was supplied to the event_command @reg() function that
1679  *	registered the trigger (see struct event_command) along with
1680  *	the trace record, rec.
1681  *
1682  * @init: An optional initialization function called for the trigger
1683  *	when the trigger is registered (via the event_command reg()
1684  *	function).  This can be used to perform per-trigger
1685  *	initialization such as incrementing a per-trigger reference
1686  *	count, for instance.  This is usually implemented by the
1687  *	generic utility function @event_trigger_init() (see
1688  *	trace_event_triggers.c).
1689  *
1690  * @free: An optional de-initialization function called for the
1691  *	trigger when the trigger is unregistered (via the
1692  *	event_command @reg() function).  This can be used to perform
1693  *	per-trigger de-initialization such as decrementing a
1694  *	per-trigger reference count and freeing corresponding trigger
1695  *	data, for instance.  This is usually implemented by the
1696  *	generic utility function @event_trigger_free() (see
1697  *	trace_event_triggers.c).
1698  *
1699  * @print: The callback function invoked to have the trigger print
1700  *	itself.  This is usually implemented by a wrapper function
1701  *	that calls the generic utility function @event_trigger_print()
1702  *	(see trace_event_triggers.c).
1703  */
1704 struct event_trigger_ops {
1705 	void			(*trigger)(struct event_trigger_data *data,
1706 					   struct trace_buffer *buffer,
1707 					   void *rec,
1708 					   struct ring_buffer_event *rbe);
1709 	int			(*init)(struct event_trigger_data *data);
1710 	void			(*free)(struct event_trigger_data *data);
1711 	int			(*print)(struct seq_file *m,
1712 					 struct event_trigger_data *data);
1713 };
1714 
1715 /**
1716  * struct event_command - callbacks and data members for event commands
1717  *
1718  * Event commands are invoked by users by writing the command name
1719  * into the 'trigger' file associated with a trace event.  The
1720  * parameters associated with a specific invocation of an event
1721  * command are used to create an event trigger instance, which is
1722  * added to the list of trigger instances associated with that trace
1723  * event.  When the event is hit, the set of triggers associated with
1724  * that event is invoked.
1725  *
1726  * The data members in this structure provide per-event command data
1727  * for various event commands.
1728  *
1729  * All the data members below, except for @post_trigger, must be set
1730  * for each event command.
1731  *
1732  * @name: The unique name that identifies the event command.  This is
1733  *	the name used when setting triggers via trigger files.
1734  *
1735  * @trigger_type: A unique id that identifies the event command
1736  *	'type'.  This value has two purposes, the first to ensure that
1737  *	only one trigger of the same type can be set at a given time
1738  *	for a particular event e.g. it doesn't make sense to have both
1739  *	a traceon and traceoff trigger attached to a single event at
1740  *	the same time, so traceon and traceoff have the same type
1741  *	though they have different names.  The @trigger_type value is
1742  *	also used as a bit value for deferring the actual trigger
1743  *	action until after the current event is finished.  Some
1744  *	commands need to do this if they themselves log to the trace
1745  *	buffer (see the @post_trigger() member below).  @trigger_type
1746  *	values are defined by adding new values to the trigger_type
1747  *	enum in include/linux/trace_events.h.
1748  *
1749  * @flags: See the enum event_command_flags below.
1750  *
1751  * All the methods below, except for @set_filter() and @unreg_all(),
1752  * must be implemented.
1753  *
1754  * @parse: The callback function responsible for parsing and
1755  *	registering the trigger written to the 'trigger' file by the
1756  *	user.  It allocates the trigger instance and registers it with
1757  *	the appropriate trace event.  It makes use of the other
1758  *	event_command callback functions to orchestrate this, and is
1759  *	usually implemented by the generic utility function
1760  *	@event_trigger_callback() (see trace_event_triggers.c).
1761  *
1762  * @reg: Adds the trigger to the list of triggers associated with the
1763  *	event, and enables the event trigger itself, after
1764  *	initializing it (via the event_trigger_ops @init() function).
1765  *	This is also where commands can use the @trigger_type value to
1766  *	make the decision as to whether or not multiple instances of
1767  *	the trigger should be allowed.  This is usually implemented by
1768  *	the generic utility function @register_trigger() (see
1769  *	trace_event_triggers.c).
1770  *
1771  * @unreg: Removes the trigger from the list of triggers associated
1772  *	with the event, and disables the event trigger itself, after
1773  *	initializing it (via the event_trigger_ops @free() function).
1774  *	This is usually implemented by the generic utility function
1775  *	@unregister_trigger() (see trace_event_triggers.c).
1776  *
1777  * @unreg_all: An optional function called to remove all the triggers
1778  *	from the list of triggers associated with the event.  Called
1779  *	when a trigger file is opened in truncate mode.
1780  *
1781  * @set_filter: An optional function called to parse and set a filter
1782  *	for the trigger.  If no @set_filter() method is set for the
1783  *	event command, filters set by the user for the command will be
1784  *	ignored.  This is usually implemented by the generic utility
1785  *	function @set_trigger_filter() (see trace_event_triggers.c).
1786  *
1787  * @get_trigger_ops: The callback function invoked to retrieve the
1788  *	event_trigger_ops implementation associated with the command.
1789  *	This callback function allows a single event_command to
1790  *	support multiple trigger implementations via different sets of
1791  *	event_trigger_ops, depending on the value of the @param
1792  *	string.
1793  */
1794 struct event_command {
1795 	struct list_head	list;
1796 	char			*name;
1797 	enum event_trigger_type	trigger_type;
1798 	int			flags;
1799 	int			(*parse)(struct event_command *cmd_ops,
1800 					 struct trace_event_file *file,
1801 					 char *glob, char *cmd,
1802 					 char *param_and_filter);
1803 	int			(*reg)(char *glob,
1804 				       struct event_trigger_data *data,
1805 				       struct trace_event_file *file);
1806 	void			(*unreg)(char *glob,
1807 					 struct event_trigger_data *data,
1808 					 struct trace_event_file *file);
1809 	void			(*unreg_all)(struct trace_event_file *file);
1810 	int			(*set_filter)(char *filter_str,
1811 					      struct event_trigger_data *data,
1812 					      struct trace_event_file *file);
1813 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1814 };
1815 
1816 /**
1817  * enum event_command_flags - flags for struct event_command
1818  *
1819  * @POST_TRIGGER: A flag that says whether or not this command needs
1820  *	to have its action delayed until after the current event has
1821  *	been closed.  Some triggers need to avoid being invoked while
1822  *	an event is currently in the process of being logged, since
1823  *	the trigger may itself log data into the trace buffer.  Thus
1824  *	we make sure the current event is committed before invoking
1825  *	those triggers.  To do that, the trigger invocation is split
1826  *	in two - the first part checks the filter using the current
1827  *	trace record; if a command has the @post_trigger flag set, it
1828  *	sets a bit for itself in the return value, otherwise it
1829  *	directly invokes the trigger.  Once all commands have been
1830  *	either invoked or set their return flag, the current record is
1831  *	either committed or discarded.  At that point, if any commands
1832  *	have deferred their triggers, those commands are finally
1833  *	invoked following the close of the current event.  In other
1834  *	words, if the event_trigger_ops @func() probe implementation
1835  *	itself logs to the trace buffer, this flag should be set,
1836  *	otherwise it can be left unspecified.
1837  *
1838  * @NEEDS_REC: A flag that says whether or not this command needs
1839  *	access to the trace record in order to perform its function,
1840  *	regardless of whether or not it has a filter associated with
1841  *	it (filters make a trigger require access to the trace record
1842  *	but are not always present).
1843  */
1844 enum event_command_flags {
1845 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1846 	EVENT_CMD_FL_NEEDS_REC		= 2,
1847 };
1848 
1849 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1850 {
1851 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1852 }
1853 
1854 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1855 {
1856 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1857 }
1858 
1859 extern int trace_event_enable_disable(struct trace_event_file *file,
1860 				      int enable, int soft_disable);
1861 extern int tracing_alloc_snapshot(void);
1862 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1863 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1864 
1865 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1866 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1867 
1868 extern const char *__start___trace_bprintk_fmt[];
1869 extern const char *__stop___trace_bprintk_fmt[];
1870 
1871 extern const char *__start___tracepoint_str[];
1872 extern const char *__stop___tracepoint_str[];
1873 
1874 void trace_printk_control(bool enabled);
1875 void trace_printk_start_comm(void);
1876 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1877 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1878 
1879 /* Used from boot time tracer */
1880 extern int trace_set_options(struct trace_array *tr, char *option);
1881 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1882 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1883 					  unsigned long size, int cpu_id);
1884 extern int tracing_set_cpumask(struct trace_array *tr,
1885 				cpumask_var_t tracing_cpumask_new);
1886 
1887 
1888 #define MAX_EVENT_NAME_LEN	64
1889 
1890 extern ssize_t trace_parse_run_command(struct file *file,
1891 		const char __user *buffer, size_t count, loff_t *ppos,
1892 		int (*createfn)(const char *));
1893 
1894 extern unsigned int err_pos(char *cmd, const char *str);
1895 extern void tracing_log_err(struct trace_array *tr,
1896 			    const char *loc, const char *cmd,
1897 			    const char **errs, u8 type, u16 pos);
1898 
1899 /*
1900  * Normal trace_printk() and friends allocates special buffers
1901  * to do the manipulation, as well as saves the print formats
1902  * into sections to display. But the trace infrastructure wants
1903  * to use these without the added overhead at the price of being
1904  * a bit slower (used mainly for warnings, where we don't care
1905  * about performance). The internal_trace_puts() is for such
1906  * a purpose.
1907  */
1908 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1909 
1910 #undef FTRACE_ENTRY
1911 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1912 	extern struct trace_event_call					\
1913 	__aligned(4) event_##call;
1914 #undef FTRACE_ENTRY_DUP
1915 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1916 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1917 #undef FTRACE_ENTRY_PACKED
1918 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1919 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1920 
1921 #include "trace_entries.h"
1922 
1923 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1924 int perf_ftrace_event_register(struct trace_event_call *call,
1925 			       enum trace_reg type, void *data);
1926 #else
1927 #define perf_ftrace_event_register NULL
1928 #endif
1929 
1930 #ifdef CONFIG_FTRACE_SYSCALLS
1931 void init_ftrace_syscalls(void);
1932 const char *get_syscall_name(int syscall);
1933 #else
1934 static inline void init_ftrace_syscalls(void) { }
1935 static inline const char *get_syscall_name(int syscall)
1936 {
1937 	return NULL;
1938 }
1939 #endif
1940 
1941 #ifdef CONFIG_EVENT_TRACING
1942 void trace_event_init(void);
1943 void trace_event_eval_update(struct trace_eval_map **map, int len);
1944 /* Used from boot time tracer */
1945 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1946 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1947 #else
1948 static inline void __init trace_event_init(void) { }
1949 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1950 #endif
1951 
1952 #ifdef CONFIG_TRACER_SNAPSHOT
1953 void tracing_snapshot_instance(struct trace_array *tr);
1954 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1955 #else
1956 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1957 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1958 {
1959 	return 0;
1960 }
1961 #endif
1962 
1963 #ifdef CONFIG_PREEMPT_TRACER
1964 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1965 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1966 #else
1967 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1968 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1969 #endif
1970 #ifdef CONFIG_IRQSOFF_TRACER
1971 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1972 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1973 #else
1974 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1975 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1976 #endif
1977 
1978 /*
1979  * Reset the state of the trace_iterator so that it can read consumed data.
1980  * Normally, the trace_iterator is used for reading the data when it is not
1981  * consumed, and must retain state.
1982  */
1983 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1984 {
1985 	memset_startat(iter, 0, seq);
1986 	iter->pos = -1;
1987 }
1988 
1989 /* Check the name is good for event/group/fields */
1990 static inline bool __is_good_name(const char *name, bool hash_ok)
1991 {
1992 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
1993 		return false;
1994 	while (*++name != '\0') {
1995 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
1996 		    (!hash_ok || *name != '-'))
1997 			return false;
1998 	}
1999 	return true;
2000 }
2001 
2002 /* Check the name is good for event/group/fields */
2003 static inline bool is_good_name(const char *name)
2004 {
2005 	return __is_good_name(name, false);
2006 }
2007 
2008 /* Check the name is good for system */
2009 static inline bool is_good_system_name(const char *name)
2010 {
2011 	return __is_good_name(name, true);
2012 }
2013 
2014 /* Convert certain expected symbols into '_' when generating event names */
2015 static inline void sanitize_event_name(char *name)
2016 {
2017 	while (*name++ != '\0')
2018 		if (*name == ':' || *name == '.')
2019 			*name = '_';
2020 }
2021 
2022 /*
2023  * This is a generic way to read and write a u64 value from a file in tracefs.
2024  *
2025  * The value is stored on the variable pointed by *val. The value needs
2026  * to be at least *min and at most *max. The write is protected by an
2027  * existing *lock.
2028  */
2029 struct trace_min_max_param {
2030 	struct mutex	*lock;
2031 	u64		*val;
2032 	u64		*min;
2033 	u64		*max;
2034 };
2035 
2036 #define U64_STR_SIZE		24	/* 20 digits max */
2037 
2038 extern const struct file_operations trace_min_max_fops;
2039 
2040 #ifdef CONFIG_RV
2041 extern int rv_init_interface(void);
2042 #else
2043 static inline int rv_init_interface(void)
2044 {
2045 	return 0;
2046 }
2047 #endif
2048 
2049 #endif /* _LINUX_KERNEL_TRACE_H */
2050