xref: /openbmc/linux/kernel/trace/trace.h (revision aa74c44b)
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 /*
117  * syscalls are special, and need special handling, this is why
118  * they are not included in trace_entries.h
119  */
120 struct syscall_trace_enter {
121 	struct trace_entry	ent;
122 	int			nr;
123 	unsigned long		args[];
124 };
125 
126 struct syscall_trace_exit {
127 	struct trace_entry	ent;
128 	int			nr;
129 	long			ret;
130 };
131 
132 struct kprobe_trace_entry_head {
133 	struct trace_entry	ent;
134 	unsigned long		ip;
135 };
136 
137 struct eprobe_trace_entry_head {
138 	struct trace_entry	ent;
139 	unsigned int		type;
140 };
141 
142 struct kretprobe_trace_entry_head {
143 	struct trace_entry	ent;
144 	unsigned long		func;
145 	unsigned long		ret_ip;
146 };
147 
148 #define TRACE_BUF_SIZE		1024
149 
150 struct trace_array;
151 
152 /*
153  * The CPU trace array - it consists of thousands of trace entries
154  * plus some other descriptor data: (for example which task started
155  * the trace, etc.)
156  */
157 struct trace_array_cpu {
158 	atomic_t		disabled;
159 	void			*buffer_page;	/* ring buffer spare */
160 
161 	unsigned long		entries;
162 	unsigned long		saved_latency;
163 	unsigned long		critical_start;
164 	unsigned long		critical_end;
165 	unsigned long		critical_sequence;
166 	unsigned long		nice;
167 	unsigned long		policy;
168 	unsigned long		rt_priority;
169 	unsigned long		skipped_entries;
170 	u64			preempt_timestamp;
171 	pid_t			pid;
172 	kuid_t			uid;
173 	char			comm[TASK_COMM_LEN];
174 
175 #ifdef CONFIG_FUNCTION_TRACER
176 	int			ftrace_ignore_pid;
177 #endif
178 	bool			ignore_pid;
179 };
180 
181 struct tracer;
182 struct trace_option_dentry;
183 
184 struct array_buffer {
185 	struct trace_array		*tr;
186 	struct trace_buffer		*buffer;
187 	struct trace_array_cpu __percpu	*data;
188 	u64				time_start;
189 	int				cpu;
190 };
191 
192 #define TRACE_FLAGS_MAX_SIZE		32
193 
194 struct trace_options {
195 	struct tracer			*tracer;
196 	struct trace_option_dentry	*topts;
197 };
198 
199 struct trace_pid_list *trace_pid_list_alloc(void);
200 void trace_pid_list_free(struct trace_pid_list *pid_list);
201 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
202 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
203 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
204 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
205 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
206 			unsigned int *next);
207 
208 enum {
209 	TRACE_PIDS		= BIT(0),
210 	TRACE_NO_PIDS		= BIT(1),
211 };
212 
213 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
214 				    struct trace_pid_list *no_pid_list)
215 {
216 	/* Return true if the pid list in type has pids */
217 	return ((type & TRACE_PIDS) && pid_list) ||
218 		((type & TRACE_NO_PIDS) && no_pid_list);
219 }
220 
221 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
222 					 struct trace_pid_list *no_pid_list)
223 {
224 	/*
225 	 * Turning off what is in @type, return true if the "other"
226 	 * pid list, still has pids in it.
227 	 */
228 	return (!(type & TRACE_PIDS) && pid_list) ||
229 		(!(type & TRACE_NO_PIDS) && no_pid_list);
230 }
231 
232 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
233 
234 /**
235  * struct cond_snapshot - conditional snapshot data and callback
236  *
237  * The cond_snapshot structure encapsulates a callback function and
238  * data associated with the snapshot for a given tracing instance.
239  *
240  * When a snapshot is taken conditionally, by invoking
241  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
242  * passed in turn to the cond_snapshot.update() function.  That data
243  * can be compared by the update() implementation with the cond_data
244  * contained within the struct cond_snapshot instance associated with
245  * the trace_array.  Because the tr->max_lock is held throughout the
246  * update() call, the update() function can directly retrieve the
247  * cond_snapshot and cond_data associated with the per-instance
248  * snapshot associated with the trace_array.
249  *
250  * The cond_snapshot.update() implementation can save data to be
251  * associated with the snapshot if it decides to, and returns 'true'
252  * in that case, or it returns 'false' if the conditional snapshot
253  * shouldn't be taken.
254  *
255  * The cond_snapshot instance is created and associated with the
256  * user-defined cond_data by tracing_cond_snapshot_enable().
257  * Likewise, the cond_snapshot instance is destroyed and is no longer
258  * associated with the trace instance by
259  * tracing_cond_snapshot_disable().
260  *
261  * The method below is required.
262  *
263  * @update: When a conditional snapshot is invoked, the update()
264  *	callback function is invoked with the tr->max_lock held.  The
265  *	update() implementation signals whether or not to actually
266  *	take the snapshot, by returning 'true' if so, 'false' if no
267  *	snapshot should be taken.  Because the max_lock is held for
268  *	the duration of update(), the implementation is safe to
269  *	directly retrieved and save any implementation data it needs
270  *	to in association with the snapshot.
271  */
272 struct cond_snapshot {
273 	void				*cond_data;
274 	cond_update_fn_t		update;
275 };
276 
277 /*
278  * struct trace_func_repeats - used to keep track of the consecutive
279  * (on the same CPU) calls of a single function.
280  */
281 struct trace_func_repeats {
282 	unsigned long	ip;
283 	unsigned long	parent_ip;
284 	unsigned long	count;
285 	u64		ts_last_call;
286 };
287 
288 /*
289  * The trace array - an array of per-CPU trace arrays. This is the
290  * highest level data structure that individual tracers deal with.
291  * They have on/off state as well:
292  */
293 struct trace_array {
294 	struct list_head	list;
295 	char			*name;
296 	struct array_buffer	array_buffer;
297 #ifdef CONFIG_TRACER_MAX_TRACE
298 	/*
299 	 * The max_buffer is used to snapshot the trace when a maximum
300 	 * latency is reached, or when the user initiates a snapshot.
301 	 * Some tracers will use this to store a maximum trace while
302 	 * it continues examining live traces.
303 	 *
304 	 * The buffers for the max_buffer are set up the same as the array_buffer
305 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
306 	 * with the buffer of the array_buffer and the buffers are reset for
307 	 * the array_buffer so the tracing can continue.
308 	 */
309 	struct array_buffer	max_buffer;
310 	bool			allocated_snapshot;
311 #endif
312 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
313 	|| defined(CONFIG_OSNOISE_TRACER)
314 	unsigned long		max_latency;
315 #ifdef CONFIG_FSNOTIFY
316 	struct dentry		*d_max_latency;
317 	struct work_struct	fsnotify_work;
318 	struct irq_work		fsnotify_irqwork;
319 #endif
320 #endif
321 	struct trace_pid_list	__rcu *filtered_pids;
322 	struct trace_pid_list	__rcu *filtered_no_pids;
323 	/*
324 	 * max_lock is used to protect the swapping of buffers
325 	 * when taking a max snapshot. The buffers themselves are
326 	 * protected by per_cpu spinlocks. But the action of the swap
327 	 * needs its own lock.
328 	 *
329 	 * This is defined as a arch_spinlock_t in order to help
330 	 * with performance when lockdep debugging is enabled.
331 	 *
332 	 * It is also used in other places outside the update_max_tr
333 	 * so it needs to be defined outside of the
334 	 * CONFIG_TRACER_MAX_TRACE.
335 	 */
336 	arch_spinlock_t		max_lock;
337 	int			buffer_disabled;
338 #ifdef CONFIG_FTRACE_SYSCALLS
339 	int			sys_refcount_enter;
340 	int			sys_refcount_exit;
341 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
342 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
343 #endif
344 	int			stop_count;
345 	int			clock_id;
346 	int			nr_topts;
347 	bool			clear_trace;
348 	int			buffer_percent;
349 	unsigned int		n_err_log_entries;
350 	struct tracer		*current_trace;
351 	unsigned int		trace_flags;
352 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
353 	unsigned int		flags;
354 	raw_spinlock_t		start_lock;
355 	struct list_head	err_log;
356 	struct dentry		*dir;
357 	struct dentry		*options;
358 	struct dentry		*percpu_dir;
359 	struct dentry		*event_dir;
360 	struct trace_options	*topts;
361 	struct list_head	systems;
362 	struct list_head	events;
363 	struct trace_event_file *trace_marker_file;
364 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
365 	int			ref;
366 	int			trace_ref;
367 #ifdef CONFIG_FUNCTION_TRACER
368 	struct ftrace_ops	*ops;
369 	struct trace_pid_list	__rcu *function_pids;
370 	struct trace_pid_list	__rcu *function_no_pids;
371 #ifdef CONFIG_DYNAMIC_FTRACE
372 	/* All of these are protected by the ftrace_lock */
373 	struct list_head	func_probes;
374 	struct list_head	mod_trace;
375 	struct list_head	mod_notrace;
376 #endif
377 	/* function tracing enabled */
378 	int			function_enabled;
379 #endif
380 	int			no_filter_buffering_ref;
381 	struct list_head	hist_vars;
382 #ifdef CONFIG_TRACER_SNAPSHOT
383 	struct cond_snapshot	*cond_snapshot;
384 #endif
385 	struct trace_func_repeats	__percpu *last_func_repeats;
386 };
387 
388 enum {
389 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
390 };
391 
392 extern struct list_head ftrace_trace_arrays;
393 
394 extern struct mutex trace_types_lock;
395 
396 extern int trace_array_get(struct trace_array *tr);
397 extern int tracing_check_open_get_tr(struct trace_array *tr);
398 extern struct trace_array *trace_array_find(const char *instance);
399 extern struct trace_array *trace_array_find_get(const char *instance);
400 
401 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
402 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
403 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
404 
405 extern bool trace_clock_in_ns(struct trace_array *tr);
406 
407 /*
408  * The global tracer (top) should be the first trace array added,
409  * but we check the flag anyway.
410  */
411 static inline struct trace_array *top_trace_array(void)
412 {
413 	struct trace_array *tr;
414 
415 	if (list_empty(&ftrace_trace_arrays))
416 		return NULL;
417 
418 	tr = list_entry(ftrace_trace_arrays.prev,
419 			typeof(*tr), list);
420 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
421 	return tr;
422 }
423 
424 #define FTRACE_CMP_TYPE(var, type) \
425 	__builtin_types_compatible_p(typeof(var), type *)
426 
427 #undef IF_ASSIGN
428 #define IF_ASSIGN(var, entry, etype, id)			\
429 	if (FTRACE_CMP_TYPE(var, etype)) {			\
430 		var = (typeof(var))(entry);			\
431 		WARN_ON(id != 0 && (entry)->type != id);	\
432 		break;						\
433 	}
434 
435 /* Will cause compile errors if type is not found. */
436 extern void __ftrace_bad_type(void);
437 
438 /*
439  * The trace_assign_type is a verifier that the entry type is
440  * the same as the type being assigned. To add new types simply
441  * add a line with the following format:
442  *
443  * IF_ASSIGN(var, ent, type, id);
444  *
445  *  Where "type" is the trace type that includes the trace_entry
446  *  as the "ent" item. And "id" is the trace identifier that is
447  *  used in the trace_type enum.
448  *
449  *  If the type can have more than one id, then use zero.
450  */
451 #define trace_assign_type(var, ent)					\
452 	do {								\
453 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
454 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
455 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
456 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
457 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
458 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
459 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
460 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
461 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
462 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
463 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
464 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
465 			  TRACE_MMIO_RW);				\
466 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
467 			  TRACE_MMIO_MAP);				\
468 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
469 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
470 			  TRACE_GRAPH_ENT);		\
471 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
472 			  TRACE_GRAPH_RET);		\
473 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
474 			  TRACE_FUNC_REPEATS);				\
475 		__ftrace_bad_type();					\
476 	} while (0)
477 
478 /*
479  * An option specific to a tracer. This is a boolean value.
480  * The bit is the bit index that sets its value on the
481  * flags value in struct tracer_flags.
482  */
483 struct tracer_opt {
484 	const char	*name; /* Will appear on the trace_options file */
485 	u32		bit; /* Mask assigned in val field in tracer_flags */
486 };
487 
488 /*
489  * The set of specific options for a tracer. Your tracer
490  * have to set the initial value of the flags val.
491  */
492 struct tracer_flags {
493 	u32			val;
494 	struct tracer_opt	*opts;
495 	struct tracer		*trace;
496 };
497 
498 /* Makes more easy to define a tracer opt */
499 #define TRACER_OPT(s, b)	.name = #s, .bit = b
500 
501 
502 struct trace_option_dentry {
503 	struct tracer_opt		*opt;
504 	struct tracer_flags		*flags;
505 	struct trace_array		*tr;
506 	struct dentry			*entry;
507 };
508 
509 /**
510  * struct tracer - a specific tracer and its callbacks to interact with tracefs
511  * @name: the name chosen to select it on the available_tracers file
512  * @init: called when one switches to this tracer (echo name > current_tracer)
513  * @reset: called when one switches to another tracer
514  * @start: called when tracing is unpaused (echo 1 > tracing_on)
515  * @stop: called when tracing is paused (echo 0 > tracing_on)
516  * @update_thresh: called when tracing_thresh is updated
517  * @open: called when the trace file is opened
518  * @pipe_open: called when the trace_pipe file is opened
519  * @close: called when the trace file is released
520  * @pipe_close: called when the trace_pipe file is released
521  * @read: override the default read callback on trace_pipe
522  * @splice_read: override the default splice_read callback on trace_pipe
523  * @selftest: selftest to run on boot (see trace_selftest.c)
524  * @print_headers: override the first lines that describe your columns
525  * @print_line: callback that prints a trace
526  * @set_flag: signals one of your private flags changed (trace_options file)
527  * @flags: your private flags
528  */
529 struct tracer {
530 	const char		*name;
531 	int			(*init)(struct trace_array *tr);
532 	void			(*reset)(struct trace_array *tr);
533 	void			(*start)(struct trace_array *tr);
534 	void			(*stop)(struct trace_array *tr);
535 	int			(*update_thresh)(struct trace_array *tr);
536 	void			(*open)(struct trace_iterator *iter);
537 	void			(*pipe_open)(struct trace_iterator *iter);
538 	void			(*close)(struct trace_iterator *iter);
539 	void			(*pipe_close)(struct trace_iterator *iter);
540 	ssize_t			(*read)(struct trace_iterator *iter,
541 					struct file *filp, char __user *ubuf,
542 					size_t cnt, loff_t *ppos);
543 	ssize_t			(*splice_read)(struct trace_iterator *iter,
544 					       struct file *filp,
545 					       loff_t *ppos,
546 					       struct pipe_inode_info *pipe,
547 					       size_t len,
548 					       unsigned int flags);
549 #ifdef CONFIG_FTRACE_STARTUP_TEST
550 	int			(*selftest)(struct tracer *trace,
551 					    struct trace_array *tr);
552 #endif
553 	void			(*print_header)(struct seq_file *m);
554 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
555 	/* If you handled the flag setting, return 0 */
556 	int			(*set_flag)(struct trace_array *tr,
557 					    u32 old_flags, u32 bit, int set);
558 	/* Return 0 if OK with change, else return non-zero */
559 	int			(*flag_changed)(struct trace_array *tr,
560 						u32 mask, int set);
561 	struct tracer		*next;
562 	struct tracer_flags	*flags;
563 	int			enabled;
564 	bool			print_max;
565 	bool			allow_instances;
566 #ifdef CONFIG_TRACER_MAX_TRACE
567 	bool			use_max_tr;
568 #endif
569 	/* True if tracer cannot be enabled in kernel param */
570 	bool			noboot;
571 };
572 
573 static inline struct ring_buffer_iter *
574 trace_buffer_iter(struct trace_iterator *iter, int cpu)
575 {
576 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
577 }
578 
579 int tracer_init(struct tracer *t, struct trace_array *tr);
580 int tracing_is_enabled(void);
581 void tracing_reset_online_cpus(struct array_buffer *buf);
582 void tracing_reset_current(int cpu);
583 void tracing_reset_all_online_cpus(void);
584 int tracing_open_generic(struct inode *inode, struct file *filp);
585 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
586 bool tracing_is_disabled(void);
587 bool tracer_tracing_is_on(struct trace_array *tr);
588 void tracer_tracing_on(struct trace_array *tr);
589 void tracer_tracing_off(struct trace_array *tr);
590 struct dentry *trace_create_file(const char *name,
591 				 umode_t mode,
592 				 struct dentry *parent,
593 				 void *data,
594 				 const struct file_operations *fops);
595 
596 int tracing_init_dentry(void);
597 
598 struct ring_buffer_event;
599 
600 struct ring_buffer_event *
601 trace_buffer_lock_reserve(struct trace_buffer *buffer,
602 			  int type,
603 			  unsigned long len,
604 			  unsigned int trace_ctx);
605 
606 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
607 						struct trace_array_cpu *data);
608 
609 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
610 					  int *ent_cpu, u64 *ent_ts);
611 
612 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
613 					struct ring_buffer_event *event);
614 
615 bool trace_is_tracepoint_string(const char *str);
616 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
617 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
618 			 va_list ap);
619 
620 int trace_empty(struct trace_iterator *iter);
621 
622 void *trace_find_next_entry_inc(struct trace_iterator *iter);
623 
624 void trace_init_global_iter(struct trace_iterator *iter);
625 
626 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
627 
628 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
629 unsigned long trace_total_entries(struct trace_array *tr);
630 
631 void trace_function(struct trace_array *tr,
632 		    unsigned long ip,
633 		    unsigned long parent_ip,
634 		    unsigned int trace_ctx);
635 void trace_graph_function(struct trace_array *tr,
636 		    unsigned long ip,
637 		    unsigned long parent_ip,
638 		    unsigned int trace_ctx);
639 void trace_latency_header(struct seq_file *m);
640 void trace_default_header(struct seq_file *m);
641 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
642 
643 void trace_graph_return(struct ftrace_graph_ret *trace);
644 int trace_graph_entry(struct ftrace_graph_ent *trace);
645 void set_graph_array(struct trace_array *tr);
646 
647 void tracing_start_cmdline_record(void);
648 void tracing_stop_cmdline_record(void);
649 void tracing_start_tgid_record(void);
650 void tracing_stop_tgid_record(void);
651 
652 int register_tracer(struct tracer *type);
653 int is_tracing_stopped(void);
654 
655 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
656 
657 extern cpumask_var_t __read_mostly tracing_buffer_mask;
658 
659 #define for_each_tracing_cpu(cpu)	\
660 	for_each_cpu(cpu, tracing_buffer_mask)
661 
662 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
663 
664 extern unsigned long tracing_thresh;
665 
666 /* PID filtering */
667 
668 extern int pid_max;
669 
670 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
671 			     pid_t search_pid);
672 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
673 			    struct trace_pid_list *filtered_no_pids,
674 			    struct task_struct *task);
675 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
676 				  struct task_struct *self,
677 				  struct task_struct *task);
678 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
679 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
680 int trace_pid_show(struct seq_file *m, void *v);
681 void trace_free_pid_list(struct trace_pid_list *pid_list);
682 int trace_pid_write(struct trace_pid_list *filtered_pids,
683 		    struct trace_pid_list **new_pid_list,
684 		    const char __user *ubuf, size_t cnt);
685 
686 #ifdef CONFIG_TRACER_MAX_TRACE
687 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
688 		   void *cond_data);
689 void update_max_tr_single(struct trace_array *tr,
690 			  struct task_struct *tsk, int cpu);
691 #endif /* CONFIG_TRACER_MAX_TRACE */
692 
693 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
694 	|| defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY)
695 #define LATENCY_FS_NOTIFY
696 #endif
697 
698 #ifdef LATENCY_FS_NOTIFY
699 void latency_fsnotify(struct trace_array *tr);
700 #else
701 static inline void latency_fsnotify(struct trace_array *tr) { }
702 #endif
703 
704 #ifdef CONFIG_STACKTRACE
705 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
706 #else
707 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
708 				 int skip)
709 {
710 }
711 #endif /* CONFIG_STACKTRACE */
712 
713 void trace_last_func_repeats(struct trace_array *tr,
714 			     struct trace_func_repeats *last_info,
715 			     unsigned int trace_ctx);
716 
717 extern u64 ftrace_now(int cpu);
718 
719 extern void trace_find_cmdline(int pid, char comm[]);
720 extern int trace_find_tgid(int pid);
721 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
722 
723 #ifdef CONFIG_DYNAMIC_FTRACE
724 extern unsigned long ftrace_update_tot_cnt;
725 extern unsigned long ftrace_number_of_pages;
726 extern unsigned long ftrace_number_of_groups;
727 void ftrace_init_trace_array(struct trace_array *tr);
728 #else
729 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
730 #endif
731 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
732 extern int DYN_FTRACE_TEST_NAME(void);
733 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
734 extern int DYN_FTRACE_TEST_NAME2(void);
735 
736 extern bool ring_buffer_expanded;
737 extern bool tracing_selftest_disabled;
738 
739 #ifdef CONFIG_FTRACE_STARTUP_TEST
740 extern void __init disable_tracing_selftest(const char *reason);
741 
742 extern int trace_selftest_startup_function(struct tracer *trace,
743 					   struct trace_array *tr);
744 extern int trace_selftest_startup_function_graph(struct tracer *trace,
745 						 struct trace_array *tr);
746 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
747 					  struct trace_array *tr);
748 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
749 					     struct trace_array *tr);
750 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
751 						 struct trace_array *tr);
752 extern int trace_selftest_startup_wakeup(struct tracer *trace,
753 					 struct trace_array *tr);
754 extern int trace_selftest_startup_nop(struct tracer *trace,
755 					 struct trace_array *tr);
756 extern int trace_selftest_startup_branch(struct tracer *trace,
757 					 struct trace_array *tr);
758 /*
759  * Tracer data references selftest functions that only occur
760  * on boot up. These can be __init functions. Thus, when selftests
761  * are enabled, then the tracers need to reference __init functions.
762  */
763 #define __tracer_data		__refdata
764 #else
765 static inline void __init disable_tracing_selftest(const char *reason)
766 {
767 }
768 /* Tracers are seldom changed. Optimize when selftests are disabled. */
769 #define __tracer_data		__read_mostly
770 #endif /* CONFIG_FTRACE_STARTUP_TEST */
771 
772 extern void *head_page(struct trace_array_cpu *data);
773 extern unsigned long long ns2usecs(u64 nsec);
774 extern int
775 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
776 extern int
777 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
778 extern int
779 trace_array_vprintk(struct trace_array *tr,
780 		    unsigned long ip, const char *fmt, va_list args);
781 int trace_array_printk_buf(struct trace_buffer *buffer,
782 			   unsigned long ip, const char *fmt, ...);
783 void trace_printk_seq(struct trace_seq *s);
784 enum print_line_t print_trace_line(struct trace_iterator *iter);
785 
786 extern char trace_find_mark(unsigned long long duration);
787 
788 struct ftrace_hash;
789 
790 struct ftrace_mod_load {
791 	struct list_head	list;
792 	char			*func;
793 	char			*module;
794 	int			 enable;
795 };
796 
797 enum {
798 	FTRACE_HASH_FL_MOD	= (1 << 0),
799 };
800 
801 struct ftrace_hash {
802 	unsigned long		size_bits;
803 	struct hlist_head	*buckets;
804 	unsigned long		count;
805 	unsigned long		flags;
806 	struct rcu_head		rcu;
807 };
808 
809 struct ftrace_func_entry *
810 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
811 
812 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
813 {
814 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
815 }
816 
817 /* Standard output formatting function used for function return traces */
818 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
819 
820 /* Flag options */
821 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
822 #define TRACE_GRAPH_PRINT_CPU           0x2
823 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
824 #define TRACE_GRAPH_PRINT_PROC          0x8
825 #define TRACE_GRAPH_PRINT_DURATION      0x10
826 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
827 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
828 #define TRACE_GRAPH_PRINT_IRQS          0x80
829 #define TRACE_GRAPH_PRINT_TAIL          0x100
830 #define TRACE_GRAPH_SLEEP_TIME          0x200
831 #define TRACE_GRAPH_GRAPH_TIME          0x400
832 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
833 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
834 
835 extern void ftrace_graph_sleep_time_control(bool enable);
836 
837 #ifdef CONFIG_FUNCTION_PROFILER
838 extern void ftrace_graph_graph_time_control(bool enable);
839 #else
840 static inline void ftrace_graph_graph_time_control(bool enable) { }
841 #endif
842 
843 extern enum print_line_t
844 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
845 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
846 extern void
847 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
848 extern void graph_trace_open(struct trace_iterator *iter);
849 extern void graph_trace_close(struct trace_iterator *iter);
850 extern int __trace_graph_entry(struct trace_array *tr,
851 			       struct ftrace_graph_ent *trace,
852 			       unsigned int trace_ctx);
853 extern void __trace_graph_return(struct trace_array *tr,
854 				 struct ftrace_graph_ret *trace,
855 				 unsigned int trace_ctx);
856 
857 #ifdef CONFIG_DYNAMIC_FTRACE
858 extern struct ftrace_hash __rcu *ftrace_graph_hash;
859 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
860 
861 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
862 {
863 	unsigned long addr = trace->func;
864 	int ret = 0;
865 	struct ftrace_hash *hash;
866 
867 	preempt_disable_notrace();
868 
869 	/*
870 	 * Have to open code "rcu_dereference_sched()" because the
871 	 * function graph tracer can be called when RCU is not
872 	 * "watching".
873 	 * Protected with schedule_on_each_cpu(ftrace_sync)
874 	 */
875 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
876 
877 	if (ftrace_hash_empty(hash)) {
878 		ret = 1;
879 		goto out;
880 	}
881 
882 	if (ftrace_lookup_ip(hash, addr)) {
883 
884 		/*
885 		 * This needs to be cleared on the return functions
886 		 * when the depth is zero.
887 		 */
888 		trace_recursion_set(TRACE_GRAPH_BIT);
889 		trace_recursion_set_depth(trace->depth);
890 
891 		/*
892 		 * If no irqs are to be traced, but a set_graph_function
893 		 * is set, and called by an interrupt handler, we still
894 		 * want to trace it.
895 		 */
896 		if (in_hardirq())
897 			trace_recursion_set(TRACE_IRQ_BIT);
898 		else
899 			trace_recursion_clear(TRACE_IRQ_BIT);
900 		ret = 1;
901 	}
902 
903 out:
904 	preempt_enable_notrace();
905 	return ret;
906 }
907 
908 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
909 {
910 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
911 	    trace->depth == trace_recursion_depth())
912 		trace_recursion_clear(TRACE_GRAPH_BIT);
913 }
914 
915 static inline int ftrace_graph_notrace_addr(unsigned long addr)
916 {
917 	int ret = 0;
918 	struct ftrace_hash *notrace_hash;
919 
920 	preempt_disable_notrace();
921 
922 	/*
923 	 * Have to open code "rcu_dereference_sched()" because the
924 	 * function graph tracer can be called when RCU is not
925 	 * "watching".
926 	 * Protected with schedule_on_each_cpu(ftrace_sync)
927 	 */
928 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
929 						 !preemptible());
930 
931 	if (ftrace_lookup_ip(notrace_hash, addr))
932 		ret = 1;
933 
934 	preempt_enable_notrace();
935 	return ret;
936 }
937 #else
938 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
939 {
940 	return 1;
941 }
942 
943 static inline int ftrace_graph_notrace_addr(unsigned long addr)
944 {
945 	return 0;
946 }
947 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
948 { }
949 #endif /* CONFIG_DYNAMIC_FTRACE */
950 
951 extern unsigned int fgraph_max_depth;
952 
953 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
954 {
955 	/* trace it when it is-nested-in or is a function enabled. */
956 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
957 		 ftrace_graph_addr(trace)) ||
958 		(trace->depth < 0) ||
959 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
960 }
961 
962 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
963 static inline enum print_line_t
964 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
965 {
966 	return TRACE_TYPE_UNHANDLED;
967 }
968 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
969 
970 extern struct list_head ftrace_pids;
971 
972 #ifdef CONFIG_FUNCTION_TRACER
973 
974 #define FTRACE_PID_IGNORE	-1
975 #define FTRACE_PID_TRACE	-2
976 
977 struct ftrace_func_command {
978 	struct list_head	list;
979 	char			*name;
980 	int			(*func)(struct trace_array *tr,
981 					struct ftrace_hash *hash,
982 					char *func, char *cmd,
983 					char *params, int enable);
984 };
985 extern bool ftrace_filter_param __initdata;
986 static inline int ftrace_trace_task(struct trace_array *tr)
987 {
988 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
989 		FTRACE_PID_IGNORE;
990 }
991 extern int ftrace_is_dead(void);
992 int ftrace_create_function_files(struct trace_array *tr,
993 				 struct dentry *parent);
994 void ftrace_destroy_function_files(struct trace_array *tr);
995 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
996 void ftrace_free_ftrace_ops(struct trace_array *tr);
997 void ftrace_init_global_array_ops(struct trace_array *tr);
998 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
999 void ftrace_reset_array_ops(struct trace_array *tr);
1000 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1001 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1002 				  struct dentry *d_tracer);
1003 void ftrace_clear_pids(struct trace_array *tr);
1004 int init_function_trace(void);
1005 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1006 #else
1007 static inline int ftrace_trace_task(struct trace_array *tr)
1008 {
1009 	return 1;
1010 }
1011 static inline int ftrace_is_dead(void) { return 0; }
1012 static inline int
1013 ftrace_create_function_files(struct trace_array *tr,
1014 			     struct dentry *parent)
1015 {
1016 	return 0;
1017 }
1018 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1019 {
1020 	return 0;
1021 }
1022 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1023 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1024 static inline __init void
1025 ftrace_init_global_array_ops(struct trace_array *tr) { }
1026 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1027 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1028 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1029 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1030 static inline int init_function_trace(void) { return 0; }
1031 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1032 /* ftace_func_t type is not defined, use macro instead of static inline */
1033 #define ftrace_init_array_ops(tr, func) do { } while (0)
1034 #endif /* CONFIG_FUNCTION_TRACER */
1035 
1036 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1037 
1038 struct ftrace_probe_ops {
1039 	void			(*func)(unsigned long ip,
1040 					unsigned long parent_ip,
1041 					struct trace_array *tr,
1042 					struct ftrace_probe_ops *ops,
1043 					void *data);
1044 	int			(*init)(struct ftrace_probe_ops *ops,
1045 					struct trace_array *tr,
1046 					unsigned long ip, void *init_data,
1047 					void **data);
1048 	void			(*free)(struct ftrace_probe_ops *ops,
1049 					struct trace_array *tr,
1050 					unsigned long ip, void *data);
1051 	int			(*print)(struct seq_file *m,
1052 					 unsigned long ip,
1053 					 struct ftrace_probe_ops *ops,
1054 					 void *data);
1055 };
1056 
1057 struct ftrace_func_mapper;
1058 typedef int (*ftrace_mapper_func)(void *data);
1059 
1060 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1061 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1062 					   unsigned long ip);
1063 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1064 			       unsigned long ip, void *data);
1065 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1066 				   unsigned long ip);
1067 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1068 			     ftrace_mapper_func free_func);
1069 
1070 extern int
1071 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1072 			       struct ftrace_probe_ops *ops, void *data);
1073 extern int
1074 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1075 				      struct ftrace_probe_ops *ops);
1076 extern void clear_ftrace_function_probes(struct trace_array *tr);
1077 
1078 int register_ftrace_command(struct ftrace_func_command *cmd);
1079 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1080 
1081 void ftrace_create_filter_files(struct ftrace_ops *ops,
1082 				struct dentry *parent);
1083 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1084 
1085 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1086 			     int len, int reset);
1087 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1088 			      int len, int reset);
1089 #else
1090 struct ftrace_func_command;
1091 
1092 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1093 {
1094 	return -EINVAL;
1095 }
1096 static inline __init int unregister_ftrace_command(char *cmd_name)
1097 {
1098 	return -EINVAL;
1099 }
1100 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1101 {
1102 }
1103 
1104 /*
1105  * The ops parameter passed in is usually undefined.
1106  * This must be a macro.
1107  */
1108 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1109 #define ftrace_destroy_filter_files(ops) do { } while (0)
1110 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1111 
1112 bool ftrace_event_is_function(struct trace_event_call *call);
1113 
1114 /*
1115  * struct trace_parser - servers for reading the user input separated by spaces
1116  * @cont: set if the input is not complete - no final space char was found
1117  * @buffer: holds the parsed user input
1118  * @idx: user input length
1119  * @size: buffer size
1120  */
1121 struct trace_parser {
1122 	bool		cont;
1123 	char		*buffer;
1124 	unsigned	idx;
1125 	unsigned	size;
1126 };
1127 
1128 static inline bool trace_parser_loaded(struct trace_parser *parser)
1129 {
1130 	return (parser->idx != 0);
1131 }
1132 
1133 static inline bool trace_parser_cont(struct trace_parser *parser)
1134 {
1135 	return parser->cont;
1136 }
1137 
1138 static inline void trace_parser_clear(struct trace_parser *parser)
1139 {
1140 	parser->cont = false;
1141 	parser->idx = 0;
1142 }
1143 
1144 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1145 extern void trace_parser_put(struct trace_parser *parser);
1146 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1147 	size_t cnt, loff_t *ppos);
1148 
1149 /*
1150  * Only create function graph options if function graph is configured.
1151  */
1152 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1153 # define FGRAPH_FLAGS						\
1154 		C(DISPLAY_GRAPH,	"display-graph"),
1155 #else
1156 # define FGRAPH_FLAGS
1157 #endif
1158 
1159 #ifdef CONFIG_BRANCH_TRACER
1160 # define BRANCH_FLAGS					\
1161 		C(BRANCH,		"branch"),
1162 #else
1163 # define BRANCH_FLAGS
1164 #endif
1165 
1166 #ifdef CONFIG_FUNCTION_TRACER
1167 # define FUNCTION_FLAGS						\
1168 		C(FUNCTION,		"function-trace"),	\
1169 		C(FUNC_FORK,		"function-fork"),
1170 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1171 #else
1172 # define FUNCTION_FLAGS
1173 # define FUNCTION_DEFAULT_FLAGS		0UL
1174 # define TRACE_ITER_FUNC_FORK		0UL
1175 #endif
1176 
1177 #ifdef CONFIG_STACKTRACE
1178 # define STACK_FLAGS				\
1179 		C(STACKTRACE,		"stacktrace"),
1180 #else
1181 # define STACK_FLAGS
1182 #endif
1183 
1184 /*
1185  * trace_iterator_flags is an enumeration that defines bit
1186  * positions into trace_flags that controls the output.
1187  *
1188  * NOTE: These bits must match the trace_options array in
1189  *       trace.c (this macro guarantees it).
1190  */
1191 #define TRACE_FLAGS						\
1192 		C(PRINT_PARENT,		"print-parent"),	\
1193 		C(SYM_OFFSET,		"sym-offset"),		\
1194 		C(SYM_ADDR,		"sym-addr"),		\
1195 		C(VERBOSE,		"verbose"),		\
1196 		C(RAW,			"raw"),			\
1197 		C(HEX,			"hex"),			\
1198 		C(BIN,			"bin"),			\
1199 		C(BLOCK,		"block"),		\
1200 		C(PRINTK,		"trace_printk"),	\
1201 		C(ANNOTATE,		"annotate"),		\
1202 		C(USERSTACKTRACE,	"userstacktrace"),	\
1203 		C(SYM_USEROBJ,		"sym-userobj"),		\
1204 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1205 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1206 		C(LATENCY_FMT,		"latency-format"),	\
1207 		C(RECORD_CMD,		"record-cmd"),		\
1208 		C(RECORD_TGID,		"record-tgid"),		\
1209 		C(OVERWRITE,		"overwrite"),		\
1210 		C(STOP_ON_FREE,		"disable_on_free"),	\
1211 		C(IRQ_INFO,		"irq-info"),		\
1212 		C(MARKERS,		"markers"),		\
1213 		C(EVENT_FORK,		"event-fork"),		\
1214 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1215 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1216 		FUNCTION_FLAGS					\
1217 		FGRAPH_FLAGS					\
1218 		STACK_FLAGS					\
1219 		BRANCH_FLAGS
1220 
1221 /*
1222  * By defining C, we can make TRACE_FLAGS a list of bit names
1223  * that will define the bits for the flag masks.
1224  */
1225 #undef C
1226 #define C(a, b) TRACE_ITER_##a##_BIT
1227 
1228 enum trace_iterator_bits {
1229 	TRACE_FLAGS
1230 	/* Make sure we don't go more than we have bits for */
1231 	TRACE_ITER_LAST_BIT
1232 };
1233 
1234 /*
1235  * By redefining C, we can make TRACE_FLAGS a list of masks that
1236  * use the bits as defined above.
1237  */
1238 #undef C
1239 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1240 
1241 enum trace_iterator_flags { TRACE_FLAGS };
1242 
1243 /*
1244  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1245  * control the output of kernel symbols.
1246  */
1247 #define TRACE_ITER_SYM_MASK \
1248 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1249 
1250 extern struct tracer nop_trace;
1251 
1252 #ifdef CONFIG_BRANCH_TRACER
1253 extern int enable_branch_tracing(struct trace_array *tr);
1254 extern void disable_branch_tracing(void);
1255 static inline int trace_branch_enable(struct trace_array *tr)
1256 {
1257 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1258 		return enable_branch_tracing(tr);
1259 	return 0;
1260 }
1261 static inline void trace_branch_disable(void)
1262 {
1263 	/* due to races, always disable */
1264 	disable_branch_tracing();
1265 }
1266 #else
1267 static inline int trace_branch_enable(struct trace_array *tr)
1268 {
1269 	return 0;
1270 }
1271 static inline void trace_branch_disable(void)
1272 {
1273 }
1274 #endif /* CONFIG_BRANCH_TRACER */
1275 
1276 /* set ring buffers to default size if not already done so */
1277 int tracing_update_buffers(void);
1278 
1279 struct ftrace_event_field {
1280 	struct list_head	link;
1281 	const char		*name;
1282 	const char		*type;
1283 	int			filter_type;
1284 	int			offset;
1285 	int			size;
1286 	int			is_signed;
1287 };
1288 
1289 struct prog_entry;
1290 
1291 struct event_filter {
1292 	struct prog_entry __rcu	*prog;
1293 	char			*filter_string;
1294 };
1295 
1296 struct event_subsystem {
1297 	struct list_head	list;
1298 	const char		*name;
1299 	struct event_filter	*filter;
1300 	int			ref_count;
1301 };
1302 
1303 struct trace_subsystem_dir {
1304 	struct list_head		list;
1305 	struct event_subsystem		*subsystem;
1306 	struct trace_array		*tr;
1307 	struct dentry			*entry;
1308 	int				ref_count;
1309 	int				nr_events;
1310 };
1311 
1312 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1313 				     struct trace_buffer *buffer,
1314 				     struct ring_buffer_event *event);
1315 
1316 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1317 				     struct trace_buffer *buffer,
1318 				     struct ring_buffer_event *event,
1319 				     unsigned int trcace_ctx,
1320 				     struct pt_regs *regs);
1321 
1322 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1323 					      struct trace_buffer *buffer,
1324 					      struct ring_buffer_event *event,
1325 					      unsigned int trace_ctx)
1326 {
1327 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1328 }
1329 
1330 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1331 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1332 void trace_buffered_event_disable(void);
1333 void trace_buffered_event_enable(void);
1334 
1335 static inline void
1336 __trace_event_discard_commit(struct trace_buffer *buffer,
1337 			     struct ring_buffer_event *event)
1338 {
1339 	if (this_cpu_read(trace_buffered_event) == event) {
1340 		/* Simply release the temp buffer and enable preemption */
1341 		this_cpu_dec(trace_buffered_event_cnt);
1342 		preempt_enable_notrace();
1343 		return;
1344 	}
1345 	/* ring_buffer_discard_commit() enables preemption */
1346 	ring_buffer_discard_commit(buffer, event);
1347 }
1348 
1349 /*
1350  * Helper function for event_trigger_unlock_commit{_regs}().
1351  * If there are event triggers attached to this event that requires
1352  * filtering against its fields, then they will be called as the
1353  * entry already holds the field information of the current event.
1354  *
1355  * It also checks if the event should be discarded or not.
1356  * It is to be discarded if the event is soft disabled and the
1357  * event was only recorded to process triggers, or if the event
1358  * filter is active and this event did not match the filters.
1359  *
1360  * Returns true if the event is discarded, false otherwise.
1361  */
1362 static inline bool
1363 __event_trigger_test_discard(struct trace_event_file *file,
1364 			     struct trace_buffer *buffer,
1365 			     struct ring_buffer_event *event,
1366 			     void *entry,
1367 			     enum event_trigger_type *tt)
1368 {
1369 	unsigned long eflags = file->flags;
1370 
1371 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1372 		*tt = event_triggers_call(file, buffer, entry, event);
1373 
1374 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1375 				    EVENT_FILE_FL_FILTERED |
1376 				    EVENT_FILE_FL_PID_FILTER))))
1377 		return false;
1378 
1379 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1380 		goto discard;
1381 
1382 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1383 	    !filter_match_preds(file->filter, entry))
1384 		goto discard;
1385 
1386 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1387 	    trace_event_ignore_this_pid(file))
1388 		goto discard;
1389 
1390 	return false;
1391  discard:
1392 	__trace_event_discard_commit(buffer, event);
1393 	return true;
1394 }
1395 
1396 /**
1397  * event_trigger_unlock_commit - handle triggers and finish event commit
1398  * @file: The file pointer associated with the event
1399  * @buffer: The ring buffer that the event is being written to
1400  * @event: The event meta data in the ring buffer
1401  * @entry: The event itself
1402  * @trace_ctx: The tracing context flags.
1403  *
1404  * This is a helper function to handle triggers that require data
1405  * from the event itself. It also tests the event against filters and
1406  * if the event is soft disabled and should be discarded.
1407  */
1408 static inline void
1409 event_trigger_unlock_commit(struct trace_event_file *file,
1410 			    struct trace_buffer *buffer,
1411 			    struct ring_buffer_event *event,
1412 			    void *entry, unsigned int trace_ctx)
1413 {
1414 	enum event_trigger_type tt = ETT_NONE;
1415 
1416 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1417 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1418 
1419 	if (tt)
1420 		event_triggers_post_call(file, tt);
1421 }
1422 
1423 #define FILTER_PRED_INVALID	((unsigned short)-1)
1424 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1425 #define FILTER_PRED_FOLD	(1 << 15)
1426 
1427 /*
1428  * The max preds is the size of unsigned short with
1429  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1430  * and FOLD flags. The other is reserved.
1431  *
1432  * 2^14 preds is way more than enough.
1433  */
1434 #define MAX_FILTER_PRED		16384
1435 
1436 struct filter_pred;
1437 struct regex;
1438 
1439 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1440 
1441 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1442 
1443 enum regex_type {
1444 	MATCH_FULL = 0,
1445 	MATCH_FRONT_ONLY,
1446 	MATCH_MIDDLE_ONLY,
1447 	MATCH_END_ONLY,
1448 	MATCH_GLOB,
1449 	MATCH_INDEX,
1450 };
1451 
1452 struct regex {
1453 	char			pattern[MAX_FILTER_STR_VAL];
1454 	int			len;
1455 	int			field_len;
1456 	regex_match_func	match;
1457 };
1458 
1459 struct filter_pred {
1460 	filter_pred_fn_t 	fn;
1461 	u64 			val;
1462 	struct regex		regex;
1463 	unsigned short		*ops;
1464 	struct ftrace_event_field *field;
1465 	int 			offset;
1466 	int			not;
1467 	int 			op;
1468 };
1469 
1470 static inline bool is_string_field(struct ftrace_event_field *field)
1471 {
1472 	return field->filter_type == FILTER_DYN_STRING ||
1473 	       field->filter_type == FILTER_RDYN_STRING ||
1474 	       field->filter_type == FILTER_STATIC_STRING ||
1475 	       field->filter_type == FILTER_PTR_STRING ||
1476 	       field->filter_type == FILTER_COMM;
1477 }
1478 
1479 static inline bool is_function_field(struct ftrace_event_field *field)
1480 {
1481 	return field->filter_type == FILTER_TRACE_FN;
1482 }
1483 
1484 extern enum regex_type
1485 filter_parse_regex(char *buff, int len, char **search, int *not);
1486 extern void print_event_filter(struct trace_event_file *file,
1487 			       struct trace_seq *s);
1488 extern int apply_event_filter(struct trace_event_file *file,
1489 			      char *filter_string);
1490 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1491 					char *filter_string);
1492 extern void print_subsystem_event_filter(struct event_subsystem *system,
1493 					 struct trace_seq *s);
1494 extern int filter_assign_type(const char *type);
1495 extern int create_event_filter(struct trace_array *tr,
1496 			       struct trace_event_call *call,
1497 			       char *filter_str, bool set_str,
1498 			       struct event_filter **filterp);
1499 extern void free_event_filter(struct event_filter *filter);
1500 
1501 struct ftrace_event_field *
1502 trace_find_event_field(struct trace_event_call *call, char *name);
1503 
1504 extern void trace_event_enable_cmd_record(bool enable);
1505 extern void trace_event_enable_tgid_record(bool enable);
1506 
1507 extern int event_trace_init(void);
1508 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1509 extern int event_trace_del_tracer(struct trace_array *tr);
1510 extern void __trace_early_add_events(struct trace_array *tr);
1511 
1512 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1513 						  const char *system,
1514 						  const char *event);
1515 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1516 						const char *system,
1517 						const char *event);
1518 
1519 static inline void *event_file_data(struct file *filp)
1520 {
1521 	return READ_ONCE(file_inode(filp)->i_private);
1522 }
1523 
1524 extern struct mutex event_mutex;
1525 extern struct list_head ftrace_events;
1526 
1527 extern const struct file_operations event_trigger_fops;
1528 extern const struct file_operations event_hist_fops;
1529 extern const struct file_operations event_hist_debug_fops;
1530 extern const struct file_operations event_inject_fops;
1531 
1532 #ifdef CONFIG_HIST_TRIGGERS
1533 extern int register_trigger_hist_cmd(void);
1534 extern int register_trigger_hist_enable_disable_cmds(void);
1535 #else
1536 static inline int register_trigger_hist_cmd(void) { return 0; }
1537 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1538 #endif
1539 
1540 extern int register_trigger_cmds(void);
1541 extern void clear_event_triggers(struct trace_array *tr);
1542 
1543 enum {
1544 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1545 };
1546 
1547 struct event_trigger_data {
1548 	unsigned long			count;
1549 	int				ref;
1550 	int				flags;
1551 	struct event_trigger_ops	*ops;
1552 	struct event_command		*cmd_ops;
1553 	struct event_filter __rcu	*filter;
1554 	char				*filter_str;
1555 	void				*private_data;
1556 	bool				paused;
1557 	bool				paused_tmp;
1558 	struct list_head		list;
1559 	char				*name;
1560 	struct list_head		named_list;
1561 	struct event_trigger_data	*named_data;
1562 };
1563 
1564 /* Avoid typos */
1565 #define ENABLE_EVENT_STR	"enable_event"
1566 #define DISABLE_EVENT_STR	"disable_event"
1567 #define ENABLE_HIST_STR		"enable_hist"
1568 #define DISABLE_HIST_STR	"disable_hist"
1569 
1570 struct enable_trigger_data {
1571 	struct trace_event_file		*file;
1572 	bool				enable;
1573 	bool				hist;
1574 };
1575 
1576 extern int event_enable_trigger_print(struct seq_file *m,
1577 				      struct event_trigger_ops *ops,
1578 				      struct event_trigger_data *data);
1579 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1580 				      struct event_trigger_data *data);
1581 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1582 				      struct trace_event_file *file,
1583 				      char *glob, char *cmd, char *param);
1584 extern int event_enable_register_trigger(char *glob,
1585 					 struct event_trigger_data *data,
1586 					 struct trace_event_file *file);
1587 extern void event_enable_unregister_trigger(char *glob,
1588 					    struct event_trigger_data *test,
1589 					    struct trace_event_file *file);
1590 extern void trigger_data_free(struct event_trigger_data *data);
1591 extern int event_trigger_init(struct event_trigger_ops *ops,
1592 			      struct event_trigger_data *data);
1593 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1594 					      int trigger_enable);
1595 extern void update_cond_flag(struct trace_event_file *file);
1596 extern int set_trigger_filter(char *filter_str,
1597 			      struct event_trigger_data *trigger_data,
1598 			      struct trace_event_file *file);
1599 extern struct event_trigger_data *find_named_trigger(const char *name);
1600 extern bool is_named_trigger(struct event_trigger_data *test);
1601 extern int save_named_trigger(const char *name,
1602 			      struct event_trigger_data *data);
1603 extern void del_named_trigger(struct event_trigger_data *data);
1604 extern void pause_named_trigger(struct event_trigger_data *data);
1605 extern void unpause_named_trigger(struct event_trigger_data *data);
1606 extern void set_named_trigger_data(struct event_trigger_data *data,
1607 				   struct event_trigger_data *named_data);
1608 extern struct event_trigger_data *
1609 get_named_trigger_data(struct event_trigger_data *data);
1610 extern int register_event_command(struct event_command *cmd);
1611 extern int unregister_event_command(struct event_command *cmd);
1612 extern int register_trigger_hist_enable_disable_cmds(void);
1613 extern bool event_trigger_check_remove(const char *glob);
1614 extern bool event_trigger_empty_param(const char *param);
1615 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1616 					 char **filter, bool param_required);
1617 extern struct event_trigger_data *
1618 event_trigger_alloc(struct event_command *cmd_ops,
1619 		    char *cmd,
1620 		    char *param,
1621 		    void *private_data);
1622 extern int event_trigger_parse_num(char *trigger,
1623 				   struct event_trigger_data *trigger_data);
1624 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1625 				    struct trace_event_file *file,
1626 				    char *param,
1627 				    struct event_trigger_data *trigger_data);
1628 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1629 				       struct event_trigger_data *trigger_data);
1630 extern int event_trigger_register(struct event_command *cmd_ops,
1631 				  struct trace_event_file *file,
1632 				  char *glob,
1633 				  char *cmd,
1634 				  char *trigger,
1635 				  struct event_trigger_data *trigger_data,
1636 				  int *n_registered);
1637 
1638 /**
1639  * struct event_trigger_ops - callbacks for trace event triggers
1640  *
1641  * The methods in this structure provide per-event trigger hooks for
1642  * various trigger operations.
1643  *
1644  * The @init and @free methods are used during trigger setup and
1645  * teardown, typically called from an event_command's @parse()
1646  * function implementation.
1647  *
1648  * The @print method is used to print the trigger spec.
1649  *
1650  * The @trigger method is the function that actually implements the
1651  * trigger and is called in the context of the triggering event
1652  * whenever that event occurs.
1653  *
1654  * All the methods below, except for @init() and @free(), must be
1655  * implemented.
1656  *
1657  * @trigger: The trigger 'probe' function called when the triggering
1658  *	event occurs.  The data passed into this callback is the data
1659  *	that was supplied to the event_command @reg() function that
1660  *	registered the trigger (see struct event_command) along with
1661  *	the trace record, rec.
1662  *
1663  * @init: An optional initialization function called for the trigger
1664  *	when the trigger is registered (via the event_command reg()
1665  *	function).  This can be used to perform per-trigger
1666  *	initialization such as incrementing a per-trigger reference
1667  *	count, for instance.  This is usually implemented by the
1668  *	generic utility function @event_trigger_init() (see
1669  *	trace_event_triggers.c).
1670  *
1671  * @free: An optional de-initialization function called for the
1672  *	trigger when the trigger is unregistered (via the
1673  *	event_command @reg() function).  This can be used to perform
1674  *	per-trigger de-initialization such as decrementing a
1675  *	per-trigger reference count and freeing corresponding trigger
1676  *	data, for instance.  This is usually implemented by the
1677  *	generic utility function @event_trigger_free() (see
1678  *	trace_event_triggers.c).
1679  *
1680  * @print: The callback function invoked to have the trigger print
1681  *	itself.  This is usually implemented by a wrapper function
1682  *	that calls the generic utility function @event_trigger_print()
1683  *	(see trace_event_triggers.c).
1684  */
1685 struct event_trigger_ops {
1686 	void			(*trigger)(struct event_trigger_data *data,
1687 					   struct trace_buffer *buffer,
1688 					   void *rec,
1689 					   struct ring_buffer_event *rbe);
1690 	int			(*init)(struct event_trigger_ops *ops,
1691 					struct event_trigger_data *data);
1692 	void			(*free)(struct event_trigger_ops *ops,
1693 					struct event_trigger_data *data);
1694 	int			(*print)(struct seq_file *m,
1695 					 struct event_trigger_ops *ops,
1696 					 struct event_trigger_data *data);
1697 };
1698 
1699 /**
1700  * struct event_command - callbacks and data members for event commands
1701  *
1702  * Event commands are invoked by users by writing the command name
1703  * into the 'trigger' file associated with a trace event.  The
1704  * parameters associated with a specific invocation of an event
1705  * command are used to create an event trigger instance, which is
1706  * added to the list of trigger instances associated with that trace
1707  * event.  When the event is hit, the set of triggers associated with
1708  * that event is invoked.
1709  *
1710  * The data members in this structure provide per-event command data
1711  * for various event commands.
1712  *
1713  * All the data members below, except for @post_trigger, must be set
1714  * for each event command.
1715  *
1716  * @name: The unique name that identifies the event command.  This is
1717  *	the name used when setting triggers via trigger files.
1718  *
1719  * @trigger_type: A unique id that identifies the event command
1720  *	'type'.  This value has two purposes, the first to ensure that
1721  *	only one trigger of the same type can be set at a given time
1722  *	for a particular event e.g. it doesn't make sense to have both
1723  *	a traceon and traceoff trigger attached to a single event at
1724  *	the same time, so traceon and traceoff have the same type
1725  *	though they have different names.  The @trigger_type value is
1726  *	also used as a bit value for deferring the actual trigger
1727  *	action until after the current event is finished.  Some
1728  *	commands need to do this if they themselves log to the trace
1729  *	buffer (see the @post_trigger() member below).  @trigger_type
1730  *	values are defined by adding new values to the trigger_type
1731  *	enum in include/linux/trace_events.h.
1732  *
1733  * @flags: See the enum event_command_flags below.
1734  *
1735  * All the methods below, except for @set_filter() and @unreg_all(),
1736  * must be implemented.
1737  *
1738  * @parse: The callback function responsible for parsing and
1739  *	registering the trigger written to the 'trigger' file by the
1740  *	user.  It allocates the trigger instance and registers it with
1741  *	the appropriate trace event.  It makes use of the other
1742  *	event_command callback functions to orchestrate this, and is
1743  *	usually implemented by the generic utility function
1744  *	@event_trigger_callback() (see trace_event_triggers.c).
1745  *
1746  * @reg: Adds the trigger to the list of triggers associated with the
1747  *	event, and enables the event trigger itself, after
1748  *	initializing it (via the event_trigger_ops @init() function).
1749  *	This is also where commands can use the @trigger_type value to
1750  *	make the decision as to whether or not multiple instances of
1751  *	the trigger should be allowed.  This is usually implemented by
1752  *	the generic utility function @register_trigger() (see
1753  *	trace_event_triggers.c).
1754  *
1755  * @unreg: Removes the trigger from the list of triggers associated
1756  *	with the event, and disables the event trigger itself, after
1757  *	initializing it (via the event_trigger_ops @free() function).
1758  *	This is usually implemented by the generic utility function
1759  *	@unregister_trigger() (see trace_event_triggers.c).
1760  *
1761  * @unreg_all: An optional function called to remove all the triggers
1762  *	from the list of triggers associated with the event.  Called
1763  *	when a trigger file is opened in truncate mode.
1764  *
1765  * @set_filter: An optional function called to parse and set a filter
1766  *	for the trigger.  If no @set_filter() method is set for the
1767  *	event command, filters set by the user for the command will be
1768  *	ignored.  This is usually implemented by the generic utility
1769  *	function @set_trigger_filter() (see trace_event_triggers.c).
1770  *
1771  * @get_trigger_ops: The callback function invoked to retrieve the
1772  *	event_trigger_ops implementation associated with the command.
1773  *	This callback function allows a single event_command to
1774  *	support multiple trigger implementations via different sets of
1775  *	event_trigger_ops, depending on the value of the @param
1776  *	string.
1777  */
1778 struct event_command {
1779 	struct list_head	list;
1780 	char			*name;
1781 	enum event_trigger_type	trigger_type;
1782 	int			flags;
1783 	int			(*parse)(struct event_command *cmd_ops,
1784 					 struct trace_event_file *file,
1785 					 char *glob, char *cmd,
1786 					 char *param_and_filter);
1787 	int			(*reg)(char *glob,
1788 				       struct event_trigger_data *data,
1789 				       struct trace_event_file *file);
1790 	void			(*unreg)(char *glob,
1791 					 struct event_trigger_data *data,
1792 					 struct trace_event_file *file);
1793 	void			(*unreg_all)(struct trace_event_file *file);
1794 	int			(*set_filter)(char *filter_str,
1795 					      struct event_trigger_data *data,
1796 					      struct trace_event_file *file);
1797 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1798 };
1799 
1800 /**
1801  * enum event_command_flags - flags for struct event_command
1802  *
1803  * @POST_TRIGGER: A flag that says whether or not this command needs
1804  *	to have its action delayed until after the current event has
1805  *	been closed.  Some triggers need to avoid being invoked while
1806  *	an event is currently in the process of being logged, since
1807  *	the trigger may itself log data into the trace buffer.  Thus
1808  *	we make sure the current event is committed before invoking
1809  *	those triggers.  To do that, the trigger invocation is split
1810  *	in two - the first part checks the filter using the current
1811  *	trace record; if a command has the @post_trigger flag set, it
1812  *	sets a bit for itself in the return value, otherwise it
1813  *	directly invokes the trigger.  Once all commands have been
1814  *	either invoked or set their return flag, the current record is
1815  *	either committed or discarded.  At that point, if any commands
1816  *	have deferred their triggers, those commands are finally
1817  *	invoked following the close of the current event.  In other
1818  *	words, if the event_trigger_ops @func() probe implementation
1819  *	itself logs to the trace buffer, this flag should be set,
1820  *	otherwise it can be left unspecified.
1821  *
1822  * @NEEDS_REC: A flag that says whether or not this command needs
1823  *	access to the trace record in order to perform its function,
1824  *	regardless of whether or not it has a filter associated with
1825  *	it (filters make a trigger require access to the trace record
1826  *	but are not always present).
1827  */
1828 enum event_command_flags {
1829 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1830 	EVENT_CMD_FL_NEEDS_REC		= 2,
1831 };
1832 
1833 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1834 {
1835 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1836 }
1837 
1838 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1839 {
1840 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1841 }
1842 
1843 extern int trace_event_enable_disable(struct trace_event_file *file,
1844 				      int enable, int soft_disable);
1845 extern int tracing_alloc_snapshot(void);
1846 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1847 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1848 
1849 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1850 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1851 
1852 extern const char *__start___trace_bprintk_fmt[];
1853 extern const char *__stop___trace_bprintk_fmt[];
1854 
1855 extern const char *__start___tracepoint_str[];
1856 extern const char *__stop___tracepoint_str[];
1857 
1858 void trace_printk_control(bool enabled);
1859 void trace_printk_start_comm(void);
1860 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1861 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1862 
1863 /* Used from boot time tracer */
1864 extern int trace_set_options(struct trace_array *tr, char *option);
1865 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1866 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1867 					  unsigned long size, int cpu_id);
1868 extern int tracing_set_cpumask(struct trace_array *tr,
1869 				cpumask_var_t tracing_cpumask_new);
1870 
1871 
1872 #define MAX_EVENT_NAME_LEN	64
1873 
1874 extern ssize_t trace_parse_run_command(struct file *file,
1875 		const char __user *buffer, size_t count, loff_t *ppos,
1876 		int (*createfn)(const char *));
1877 
1878 extern unsigned int err_pos(char *cmd, const char *str);
1879 extern void tracing_log_err(struct trace_array *tr,
1880 			    const char *loc, const char *cmd,
1881 			    const char **errs, u8 type, u8 pos);
1882 
1883 /*
1884  * Normal trace_printk() and friends allocates special buffers
1885  * to do the manipulation, as well as saves the print formats
1886  * into sections to display. But the trace infrastructure wants
1887  * to use these without the added overhead at the price of being
1888  * a bit slower (used mainly for warnings, where we don't care
1889  * about performance). The internal_trace_puts() is for such
1890  * a purpose.
1891  */
1892 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1893 
1894 #undef FTRACE_ENTRY
1895 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1896 	extern struct trace_event_call					\
1897 	__aligned(4) event_##call;
1898 #undef FTRACE_ENTRY_DUP
1899 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1900 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1901 #undef FTRACE_ENTRY_PACKED
1902 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1903 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1904 
1905 #include "trace_entries.h"
1906 
1907 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1908 int perf_ftrace_event_register(struct trace_event_call *call,
1909 			       enum trace_reg type, void *data);
1910 #else
1911 #define perf_ftrace_event_register NULL
1912 #endif
1913 
1914 #ifdef CONFIG_FTRACE_SYSCALLS
1915 void init_ftrace_syscalls(void);
1916 const char *get_syscall_name(int syscall);
1917 #else
1918 static inline void init_ftrace_syscalls(void) { }
1919 static inline const char *get_syscall_name(int syscall)
1920 {
1921 	return NULL;
1922 }
1923 #endif
1924 
1925 #ifdef CONFIG_EVENT_TRACING
1926 void trace_event_init(void);
1927 void trace_event_eval_update(struct trace_eval_map **map, int len);
1928 /* Used from boot time tracer */
1929 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1930 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1931 #else
1932 static inline void __init trace_event_init(void) { }
1933 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1934 #endif
1935 
1936 #ifdef CONFIG_TRACER_SNAPSHOT
1937 void tracing_snapshot_instance(struct trace_array *tr);
1938 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1939 #else
1940 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1941 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1942 {
1943 	return 0;
1944 }
1945 #endif
1946 
1947 #ifdef CONFIG_PREEMPT_TRACER
1948 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1949 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1950 #else
1951 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1952 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1953 #endif
1954 #ifdef CONFIG_IRQSOFF_TRACER
1955 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1956 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1957 #else
1958 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1959 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1960 #endif
1961 
1962 extern struct trace_iterator *tracepoint_print_iter;
1963 
1964 /*
1965  * Reset the state of the trace_iterator so that it can read consumed data.
1966  * Normally, the trace_iterator is used for reading the data when it is not
1967  * consumed, and must retain state.
1968  */
1969 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1970 {
1971 	memset_startat(iter, 0, seq);
1972 	iter->pos = -1;
1973 }
1974 
1975 /* Check the name is good for event/group/fields */
1976 static inline bool is_good_name(const char *name)
1977 {
1978 	if (!isalpha(*name) && *name != '_')
1979 		return false;
1980 	while (*++name != '\0') {
1981 		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1982 			return false;
1983 	}
1984 	return true;
1985 }
1986 
1987 /* Convert certain expected symbols into '_' when generating event names */
1988 static inline void sanitize_event_name(char *name)
1989 {
1990 	while (*name++ != '\0')
1991 		if (*name == ':' || *name == '.')
1992 			*name = '_';
1993 }
1994 
1995 /*
1996  * This is a generic way to read and write a u64 value from a file in tracefs.
1997  *
1998  * The value is stored on the variable pointed by *val. The value needs
1999  * to be at least *min and at most *max. The write is protected by an
2000  * existing *lock.
2001  */
2002 struct trace_min_max_param {
2003 	struct mutex	*lock;
2004 	u64		*val;
2005 	u64		*min;
2006 	u64		*max;
2007 };
2008 
2009 #define U64_STR_SIZE		24	/* 20 digits max */
2010 
2011 extern const struct file_operations trace_min_max_fops;
2012 
2013 #endif /* _LINUX_KERNEL_TRACE_H */
2014