xref: /openbmc/linux/kernel/trace/trace.h (revision e65e175b)
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 };
140 
141 struct kretprobe_trace_entry_head {
142 	struct trace_entry	ent;
143 	unsigned long		func;
144 	unsigned long		ret_ip;
145 };
146 
147 #define TRACE_BUF_SIZE		1024
148 
149 struct trace_array;
150 
151 /*
152  * The CPU trace array - it consists of thousands of trace entries
153  * plus some other descriptor data: (for example which task started
154  * the trace, etc.)
155  */
156 struct trace_array_cpu {
157 	atomic_t		disabled;
158 	void			*buffer_page;	/* ring buffer spare */
159 
160 	unsigned long		entries;
161 	unsigned long		saved_latency;
162 	unsigned long		critical_start;
163 	unsigned long		critical_end;
164 	unsigned long		critical_sequence;
165 	unsigned long		nice;
166 	unsigned long		policy;
167 	unsigned long		rt_priority;
168 	unsigned long		skipped_entries;
169 	u64			preempt_timestamp;
170 	pid_t			pid;
171 	kuid_t			uid;
172 	char			comm[TASK_COMM_LEN];
173 
174 #ifdef CONFIG_FUNCTION_TRACER
175 	int			ftrace_ignore_pid;
176 #endif
177 	bool			ignore_pid;
178 };
179 
180 struct tracer;
181 struct trace_option_dentry;
182 
183 struct array_buffer {
184 	struct trace_array		*tr;
185 	struct trace_buffer		*buffer;
186 	struct trace_array_cpu __percpu	*data;
187 	u64				time_start;
188 	int				cpu;
189 };
190 
191 #define TRACE_FLAGS_MAX_SIZE		32
192 
193 struct trace_options {
194 	struct tracer			*tracer;
195 	struct trace_option_dentry	*topts;
196 };
197 
198 struct trace_pid_list *trace_pid_list_alloc(void);
199 void trace_pid_list_free(struct trace_pid_list *pid_list);
200 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
201 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
202 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
203 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
204 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
205 			unsigned int *next);
206 
207 enum {
208 	TRACE_PIDS		= BIT(0),
209 	TRACE_NO_PIDS		= BIT(1),
210 };
211 
212 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
213 				    struct trace_pid_list *no_pid_list)
214 {
215 	/* Return true if the pid list in type has pids */
216 	return ((type & TRACE_PIDS) && pid_list) ||
217 		((type & TRACE_NO_PIDS) && no_pid_list);
218 }
219 
220 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
221 					 struct trace_pid_list *no_pid_list)
222 {
223 	/*
224 	 * Turning off what is in @type, return true if the "other"
225 	 * pid list, still has pids in it.
226 	 */
227 	return (!(type & TRACE_PIDS) && pid_list) ||
228 		(!(type & TRACE_NO_PIDS) && no_pid_list);
229 }
230 
231 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
232 
233 /**
234  * struct cond_snapshot - conditional snapshot data and callback
235  *
236  * The cond_snapshot structure encapsulates a callback function and
237  * data associated with the snapshot for a given tracing instance.
238  *
239  * When a snapshot is taken conditionally, by invoking
240  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
241  * passed in turn to the cond_snapshot.update() function.  That data
242  * can be compared by the update() implementation with the cond_data
243  * contained within the struct cond_snapshot instance associated with
244  * the trace_array.  Because the tr->max_lock is held throughout the
245  * update() call, the update() function can directly retrieve the
246  * cond_snapshot and cond_data associated with the per-instance
247  * snapshot associated with the trace_array.
248  *
249  * The cond_snapshot.update() implementation can save data to be
250  * associated with the snapshot if it decides to, and returns 'true'
251  * in that case, or it returns 'false' if the conditional snapshot
252  * shouldn't be taken.
253  *
254  * The cond_snapshot instance is created and associated with the
255  * user-defined cond_data by tracing_cond_snapshot_enable().
256  * Likewise, the cond_snapshot instance is destroyed and is no longer
257  * associated with the trace instance by
258  * tracing_cond_snapshot_disable().
259  *
260  * The method below is required.
261  *
262  * @update: When a conditional snapshot is invoked, the update()
263  *	callback function is invoked with the tr->max_lock held.  The
264  *	update() implementation signals whether or not to actually
265  *	take the snapshot, by returning 'true' if so, 'false' if no
266  *	snapshot should be taken.  Because the max_lock is held for
267  *	the duration of update(), the implementation is safe to
268  *	directly retrieved and save any implementation data it needs
269  *	to in association with the snapshot.
270  */
271 struct cond_snapshot {
272 	void				*cond_data;
273 	cond_update_fn_t		update;
274 };
275 
276 /*
277  * struct trace_func_repeats - used to keep track of the consecutive
278  * (on the same CPU) calls of a single function.
279  */
280 struct trace_func_repeats {
281 	unsigned long	ip;
282 	unsigned long	parent_ip;
283 	unsigned long	count;
284 	u64		ts_last_call;
285 };
286 
287 /*
288  * The trace array - an array of per-CPU trace arrays. This is the
289  * highest level data structure that individual tracers deal with.
290  * They have on/off state as well:
291  */
292 struct trace_array {
293 	struct list_head	list;
294 	char			*name;
295 	struct array_buffer	array_buffer;
296 #ifdef CONFIG_TRACER_MAX_TRACE
297 	/*
298 	 * The max_buffer is used to snapshot the trace when a maximum
299 	 * latency is reached, or when the user initiates a snapshot.
300 	 * Some tracers will use this to store a maximum trace while
301 	 * it continues examining live traces.
302 	 *
303 	 * The buffers for the max_buffer are set up the same as the array_buffer
304 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
305 	 * with the buffer of the array_buffer and the buffers are reset for
306 	 * the array_buffer so the tracing can continue.
307 	 */
308 	struct array_buffer	max_buffer;
309 	bool			allocated_snapshot;
310 #endif
311 #ifdef CONFIG_TRACER_MAX_TRACE
312 	unsigned long		max_latency;
313 #ifdef CONFIG_FSNOTIFY
314 	struct dentry		*d_max_latency;
315 	struct work_struct	fsnotify_work;
316 	struct irq_work		fsnotify_irqwork;
317 #endif
318 #endif
319 	struct trace_pid_list	__rcu *filtered_pids;
320 	struct trace_pid_list	__rcu *filtered_no_pids;
321 	/*
322 	 * max_lock is used to protect the swapping of buffers
323 	 * when taking a max snapshot. The buffers themselves are
324 	 * protected by per_cpu spinlocks. But the action of the swap
325 	 * needs its own lock.
326 	 *
327 	 * This is defined as a arch_spinlock_t in order to help
328 	 * with performance when lockdep debugging is enabled.
329 	 *
330 	 * It is also used in other places outside the update_max_tr
331 	 * so it needs to be defined outside of the
332 	 * CONFIG_TRACER_MAX_TRACE.
333 	 */
334 	arch_spinlock_t		max_lock;
335 	int			buffer_disabled;
336 #ifdef CONFIG_FTRACE_SYSCALLS
337 	int			sys_refcount_enter;
338 	int			sys_refcount_exit;
339 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
340 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
341 #endif
342 	int			stop_count;
343 	int			clock_id;
344 	int			nr_topts;
345 	bool			clear_trace;
346 	int			buffer_percent;
347 	unsigned int		n_err_log_entries;
348 	struct tracer		*current_trace;
349 	unsigned int		trace_flags;
350 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
351 	unsigned int		flags;
352 	raw_spinlock_t		start_lock;
353 	struct list_head	err_log;
354 	struct dentry		*dir;
355 	struct dentry		*options;
356 	struct dentry		*percpu_dir;
357 	struct dentry		*event_dir;
358 	struct trace_options	*topts;
359 	struct list_head	systems;
360 	struct list_head	events;
361 	struct trace_event_file *trace_marker_file;
362 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
363 	int			ref;
364 	int			trace_ref;
365 #ifdef CONFIG_FUNCTION_TRACER
366 	struct ftrace_ops	*ops;
367 	struct trace_pid_list	__rcu *function_pids;
368 	struct trace_pid_list	__rcu *function_no_pids;
369 #ifdef CONFIG_DYNAMIC_FTRACE
370 	/* All of these are protected by the ftrace_lock */
371 	struct list_head	func_probes;
372 	struct list_head	mod_trace;
373 	struct list_head	mod_notrace;
374 #endif
375 	/* function tracing enabled */
376 	int			function_enabled;
377 #endif
378 	int			no_filter_buffering_ref;
379 	struct list_head	hist_vars;
380 #ifdef CONFIG_TRACER_SNAPSHOT
381 	struct cond_snapshot	*cond_snapshot;
382 #endif
383 	struct trace_func_repeats	__percpu *last_func_repeats;
384 };
385 
386 enum {
387 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
388 };
389 
390 extern struct list_head ftrace_trace_arrays;
391 
392 extern struct mutex trace_types_lock;
393 
394 extern int trace_array_get(struct trace_array *tr);
395 extern int tracing_check_open_get_tr(struct trace_array *tr);
396 extern struct trace_array *trace_array_find(const char *instance);
397 extern struct trace_array *trace_array_find_get(const char *instance);
398 
399 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
400 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
401 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
402 
403 extern bool trace_clock_in_ns(struct trace_array *tr);
404 
405 /*
406  * The global tracer (top) should be the first trace array added,
407  * but we check the flag anyway.
408  */
409 static inline struct trace_array *top_trace_array(void)
410 {
411 	struct trace_array *tr;
412 
413 	if (list_empty(&ftrace_trace_arrays))
414 		return NULL;
415 
416 	tr = list_entry(ftrace_trace_arrays.prev,
417 			typeof(*tr), list);
418 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
419 	return tr;
420 }
421 
422 #define FTRACE_CMP_TYPE(var, type) \
423 	__builtin_types_compatible_p(typeof(var), type *)
424 
425 #undef IF_ASSIGN
426 #define IF_ASSIGN(var, entry, etype, id)			\
427 	if (FTRACE_CMP_TYPE(var, etype)) {			\
428 		var = (typeof(var))(entry);			\
429 		WARN_ON(id != 0 && (entry)->type != id);	\
430 		break;						\
431 	}
432 
433 /* Will cause compile errors if type is not found. */
434 extern void __ftrace_bad_type(void);
435 
436 /*
437  * The trace_assign_type is a verifier that the entry type is
438  * the same as the type being assigned. To add new types simply
439  * add a line with the following format:
440  *
441  * IF_ASSIGN(var, ent, type, id);
442  *
443  *  Where "type" is the trace type that includes the trace_entry
444  *  as the "ent" item. And "id" is the trace identifier that is
445  *  used in the trace_type enum.
446  *
447  *  If the type can have more than one id, then use zero.
448  */
449 #define trace_assign_type(var, ent)					\
450 	do {								\
451 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
452 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
453 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
454 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
455 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
456 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
457 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
458 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
459 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
460 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
461 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
462 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
463 			  TRACE_MMIO_RW);				\
464 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
465 			  TRACE_MMIO_MAP);				\
466 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
467 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
468 			  TRACE_GRAPH_ENT);		\
469 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
470 			  TRACE_GRAPH_RET);		\
471 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
472 			  TRACE_FUNC_REPEATS);				\
473 		__ftrace_bad_type();					\
474 	} while (0)
475 
476 /*
477  * An option specific to a tracer. This is a boolean value.
478  * The bit is the bit index that sets its value on the
479  * flags value in struct tracer_flags.
480  */
481 struct tracer_opt {
482 	const char	*name; /* Will appear on the trace_options file */
483 	u32		bit; /* Mask assigned in val field in tracer_flags */
484 };
485 
486 /*
487  * The set of specific options for a tracer. Your tracer
488  * have to set the initial value of the flags val.
489  */
490 struct tracer_flags {
491 	u32			val;
492 	struct tracer_opt	*opts;
493 	struct tracer		*trace;
494 };
495 
496 /* Makes more easy to define a tracer opt */
497 #define TRACER_OPT(s, b)	.name = #s, .bit = b
498 
499 
500 struct trace_option_dentry {
501 	struct tracer_opt		*opt;
502 	struct tracer_flags		*flags;
503 	struct trace_array		*tr;
504 	struct dentry			*entry;
505 };
506 
507 /**
508  * struct tracer - a specific tracer and its callbacks to interact with tracefs
509  * @name: the name chosen to select it on the available_tracers file
510  * @init: called when one switches to this tracer (echo name > current_tracer)
511  * @reset: called when one switches to another tracer
512  * @start: called when tracing is unpaused (echo 1 > tracing_on)
513  * @stop: called when tracing is paused (echo 0 > tracing_on)
514  * @update_thresh: called when tracing_thresh is updated
515  * @open: called when the trace file is opened
516  * @pipe_open: called when the trace_pipe file is opened
517  * @close: called when the trace file is released
518  * @pipe_close: called when the trace_pipe file is released
519  * @read: override the default read callback on trace_pipe
520  * @splice_read: override the default splice_read callback on trace_pipe
521  * @selftest: selftest to run on boot (see trace_selftest.c)
522  * @print_headers: override the first lines that describe your columns
523  * @print_line: callback that prints a trace
524  * @set_flag: signals one of your private flags changed (trace_options file)
525  * @flags: your private flags
526  */
527 struct tracer {
528 	const char		*name;
529 	int			(*init)(struct trace_array *tr);
530 	void			(*reset)(struct trace_array *tr);
531 	void			(*start)(struct trace_array *tr);
532 	void			(*stop)(struct trace_array *tr);
533 	int			(*update_thresh)(struct trace_array *tr);
534 	void			(*open)(struct trace_iterator *iter);
535 	void			(*pipe_open)(struct trace_iterator *iter);
536 	void			(*close)(struct trace_iterator *iter);
537 	void			(*pipe_close)(struct trace_iterator *iter);
538 	ssize_t			(*read)(struct trace_iterator *iter,
539 					struct file *filp, char __user *ubuf,
540 					size_t cnt, loff_t *ppos);
541 	ssize_t			(*splice_read)(struct trace_iterator *iter,
542 					       struct file *filp,
543 					       loff_t *ppos,
544 					       struct pipe_inode_info *pipe,
545 					       size_t len,
546 					       unsigned int flags);
547 #ifdef CONFIG_FTRACE_STARTUP_TEST
548 	int			(*selftest)(struct tracer *trace,
549 					    struct trace_array *tr);
550 #endif
551 	void			(*print_header)(struct seq_file *m);
552 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
553 	/* If you handled the flag setting, return 0 */
554 	int			(*set_flag)(struct trace_array *tr,
555 					    u32 old_flags, u32 bit, int set);
556 	/* Return 0 if OK with change, else return non-zero */
557 	int			(*flag_changed)(struct trace_array *tr,
558 						u32 mask, int set);
559 	struct tracer		*next;
560 	struct tracer_flags	*flags;
561 	int			enabled;
562 	bool			print_max;
563 	bool			allow_instances;
564 #ifdef CONFIG_TRACER_MAX_TRACE
565 	bool			use_max_tr;
566 #endif
567 	/* True if tracer cannot be enabled in kernel param */
568 	bool			noboot;
569 };
570 
571 static inline struct ring_buffer_iter *
572 trace_buffer_iter(struct trace_iterator *iter, int cpu)
573 {
574 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
575 }
576 
577 int tracer_init(struct tracer *t, struct trace_array *tr);
578 int tracing_is_enabled(void);
579 void tracing_reset_online_cpus(struct array_buffer *buf);
580 void tracing_reset_current(int cpu);
581 void tracing_reset_all_online_cpus(void);
582 void tracing_reset_all_online_cpus_unlocked(void);
583 int tracing_open_generic(struct inode *inode, struct file *filp);
584 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
585 bool tracing_is_disabled(void);
586 bool tracer_tracing_is_on(struct trace_array *tr);
587 void tracer_tracing_on(struct trace_array *tr);
588 void tracer_tracing_off(struct trace_array *tr);
589 struct dentry *trace_create_file(const char *name,
590 				 umode_t mode,
591 				 struct dentry *parent,
592 				 void *data,
593 				 const struct file_operations *fops);
594 
595 int tracing_init_dentry(void);
596 
597 struct ring_buffer_event;
598 
599 struct ring_buffer_event *
600 trace_buffer_lock_reserve(struct trace_buffer *buffer,
601 			  int type,
602 			  unsigned long len,
603 			  unsigned int trace_ctx);
604 
605 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
606 						struct trace_array_cpu *data);
607 
608 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
609 					  int *ent_cpu, u64 *ent_ts);
610 
611 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
612 					struct ring_buffer_event *event);
613 
614 bool trace_is_tracepoint_string(const char *str);
615 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
616 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
617 			 va_list ap) __printf(2, 0);
618 
619 int trace_empty(struct trace_iterator *iter);
620 
621 void *trace_find_next_entry_inc(struct trace_iterator *iter);
622 
623 void trace_init_global_iter(struct trace_iterator *iter);
624 
625 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
626 
627 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
628 unsigned long trace_total_entries(struct trace_array *tr);
629 
630 void trace_function(struct trace_array *tr,
631 		    unsigned long ip,
632 		    unsigned long parent_ip,
633 		    unsigned int trace_ctx);
634 void trace_graph_function(struct trace_array *tr,
635 		    unsigned long ip,
636 		    unsigned long parent_ip,
637 		    unsigned int trace_ctx);
638 void trace_latency_header(struct seq_file *m);
639 void trace_default_header(struct seq_file *m);
640 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
641 
642 void trace_graph_return(struct ftrace_graph_ret *trace);
643 int trace_graph_entry(struct ftrace_graph_ent *trace);
644 void set_graph_array(struct trace_array *tr);
645 
646 void tracing_start_cmdline_record(void);
647 void tracing_stop_cmdline_record(void);
648 void tracing_start_tgid_record(void);
649 void tracing_stop_tgid_record(void);
650 
651 int register_tracer(struct tracer *type);
652 int is_tracing_stopped(void);
653 
654 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
655 
656 extern cpumask_var_t __read_mostly tracing_buffer_mask;
657 
658 #define for_each_tracing_cpu(cpu)	\
659 	for_each_cpu(cpu, tracing_buffer_mask)
660 
661 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
662 
663 extern unsigned long tracing_thresh;
664 
665 /* PID filtering */
666 
667 extern int pid_max;
668 
669 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
670 			     pid_t search_pid);
671 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
672 			    struct trace_pid_list *filtered_no_pids,
673 			    struct task_struct *task);
674 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
675 				  struct task_struct *self,
676 				  struct task_struct *task);
677 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
678 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
679 int trace_pid_show(struct seq_file *m, void *v);
680 void trace_free_pid_list(struct trace_pid_list *pid_list);
681 int trace_pid_write(struct trace_pid_list *filtered_pids,
682 		    struct trace_pid_list **new_pid_list,
683 		    const char __user *ubuf, size_t cnt);
684 
685 #ifdef CONFIG_TRACER_MAX_TRACE
686 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
687 		   void *cond_data);
688 void update_max_tr_single(struct trace_array *tr,
689 			  struct task_struct *tsk, int cpu);
690 
691 #ifdef CONFIG_FSNOTIFY
692 #define LATENCY_FS_NOTIFY
693 #endif
694 #endif /* CONFIG_TRACER_MAX_TRACE */
695 
696 #ifdef LATENCY_FS_NOTIFY
697 void latency_fsnotify(struct trace_array *tr);
698 #else
699 static inline void latency_fsnotify(struct trace_array *tr) { }
700 #endif
701 
702 #ifdef CONFIG_STACKTRACE
703 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
704 #else
705 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
706 				 int skip)
707 {
708 }
709 #endif /* CONFIG_STACKTRACE */
710 
711 void trace_last_func_repeats(struct trace_array *tr,
712 			     struct trace_func_repeats *last_info,
713 			     unsigned int trace_ctx);
714 
715 extern u64 ftrace_now(int cpu);
716 
717 extern void trace_find_cmdline(int pid, char comm[]);
718 extern int trace_find_tgid(int pid);
719 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
720 
721 #ifdef CONFIG_DYNAMIC_FTRACE
722 extern unsigned long ftrace_update_tot_cnt;
723 extern unsigned long ftrace_number_of_pages;
724 extern unsigned long ftrace_number_of_groups;
725 void ftrace_init_trace_array(struct trace_array *tr);
726 #else
727 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
728 #endif
729 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
730 extern int DYN_FTRACE_TEST_NAME(void);
731 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
732 extern int DYN_FTRACE_TEST_NAME2(void);
733 
734 extern bool ring_buffer_expanded;
735 extern bool tracing_selftest_disabled;
736 
737 #ifdef CONFIG_FTRACE_STARTUP_TEST
738 extern void __init disable_tracing_selftest(const char *reason);
739 
740 extern int trace_selftest_startup_function(struct tracer *trace,
741 					   struct trace_array *tr);
742 extern int trace_selftest_startup_function_graph(struct tracer *trace,
743 						 struct trace_array *tr);
744 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
745 					  struct trace_array *tr);
746 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
747 					     struct trace_array *tr);
748 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
749 						 struct trace_array *tr);
750 extern int trace_selftest_startup_wakeup(struct tracer *trace,
751 					 struct trace_array *tr);
752 extern int trace_selftest_startup_nop(struct tracer *trace,
753 					 struct trace_array *tr);
754 extern int trace_selftest_startup_branch(struct tracer *trace,
755 					 struct trace_array *tr);
756 /*
757  * Tracer data references selftest functions that only occur
758  * on boot up. These can be __init functions. Thus, when selftests
759  * are enabled, then the tracers need to reference __init functions.
760  */
761 #define __tracer_data		__refdata
762 #else
763 static inline void __init disable_tracing_selftest(const char *reason)
764 {
765 }
766 /* Tracers are seldom changed. Optimize when selftests are disabled. */
767 #define __tracer_data		__read_mostly
768 #endif /* CONFIG_FTRACE_STARTUP_TEST */
769 
770 extern void *head_page(struct trace_array_cpu *data);
771 extern unsigned long long ns2usecs(u64 nsec);
772 extern int
773 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
774 extern int
775 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
776 extern int
777 trace_array_vprintk(struct trace_array *tr,
778 		    unsigned long ip, const char *fmt, va_list args);
779 int trace_array_printk_buf(struct trace_buffer *buffer,
780 			   unsigned long ip, const char *fmt, ...);
781 void trace_printk_seq(struct trace_seq *s);
782 enum print_line_t print_trace_line(struct trace_iterator *iter);
783 
784 extern char trace_find_mark(unsigned long long duration);
785 
786 struct ftrace_hash;
787 
788 struct ftrace_mod_load {
789 	struct list_head	list;
790 	char			*func;
791 	char			*module;
792 	int			 enable;
793 };
794 
795 enum {
796 	FTRACE_HASH_FL_MOD	= (1 << 0),
797 };
798 
799 struct ftrace_hash {
800 	unsigned long		size_bits;
801 	struct hlist_head	*buckets;
802 	unsigned long		count;
803 	unsigned long		flags;
804 	struct rcu_head		rcu;
805 };
806 
807 struct ftrace_func_entry *
808 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
809 
810 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
811 {
812 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
813 }
814 
815 /* Standard output formatting function used for function return traces */
816 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
817 
818 /* Flag options */
819 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
820 #define TRACE_GRAPH_PRINT_CPU           0x2
821 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
822 #define TRACE_GRAPH_PRINT_PROC          0x8
823 #define TRACE_GRAPH_PRINT_DURATION      0x10
824 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
825 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
826 #define TRACE_GRAPH_PRINT_IRQS          0x80
827 #define TRACE_GRAPH_PRINT_TAIL          0x100
828 #define TRACE_GRAPH_SLEEP_TIME          0x200
829 #define TRACE_GRAPH_GRAPH_TIME          0x400
830 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
831 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
832 
833 extern void ftrace_graph_sleep_time_control(bool enable);
834 
835 #ifdef CONFIG_FUNCTION_PROFILER
836 extern void ftrace_graph_graph_time_control(bool enable);
837 #else
838 static inline void ftrace_graph_graph_time_control(bool enable) { }
839 #endif
840 
841 extern enum print_line_t
842 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
843 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
844 extern void
845 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
846 extern void graph_trace_open(struct trace_iterator *iter);
847 extern void graph_trace_close(struct trace_iterator *iter);
848 extern int __trace_graph_entry(struct trace_array *tr,
849 			       struct ftrace_graph_ent *trace,
850 			       unsigned int trace_ctx);
851 extern void __trace_graph_return(struct trace_array *tr,
852 				 struct ftrace_graph_ret *trace,
853 				 unsigned int trace_ctx);
854 
855 #ifdef CONFIG_DYNAMIC_FTRACE
856 extern struct ftrace_hash __rcu *ftrace_graph_hash;
857 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
858 
859 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
860 {
861 	unsigned long addr = trace->func;
862 	int ret = 0;
863 	struct ftrace_hash *hash;
864 
865 	preempt_disable_notrace();
866 
867 	/*
868 	 * Have to open code "rcu_dereference_sched()" because the
869 	 * function graph tracer can be called when RCU is not
870 	 * "watching".
871 	 * Protected with schedule_on_each_cpu(ftrace_sync)
872 	 */
873 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
874 
875 	if (ftrace_hash_empty(hash)) {
876 		ret = 1;
877 		goto out;
878 	}
879 
880 	if (ftrace_lookup_ip(hash, addr)) {
881 
882 		/*
883 		 * This needs to be cleared on the return functions
884 		 * when the depth is zero.
885 		 */
886 		trace_recursion_set(TRACE_GRAPH_BIT);
887 		trace_recursion_set_depth(trace->depth);
888 
889 		/*
890 		 * If no irqs are to be traced, but a set_graph_function
891 		 * is set, and called by an interrupt handler, we still
892 		 * want to trace it.
893 		 */
894 		if (in_hardirq())
895 			trace_recursion_set(TRACE_IRQ_BIT);
896 		else
897 			trace_recursion_clear(TRACE_IRQ_BIT);
898 		ret = 1;
899 	}
900 
901 out:
902 	preempt_enable_notrace();
903 	return ret;
904 }
905 
906 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
907 {
908 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
909 	    trace->depth == trace_recursion_depth())
910 		trace_recursion_clear(TRACE_GRAPH_BIT);
911 }
912 
913 static inline int ftrace_graph_notrace_addr(unsigned long addr)
914 {
915 	int ret = 0;
916 	struct ftrace_hash *notrace_hash;
917 
918 	preempt_disable_notrace();
919 
920 	/*
921 	 * Have to open code "rcu_dereference_sched()" because the
922 	 * function graph tracer can be called when RCU is not
923 	 * "watching".
924 	 * Protected with schedule_on_each_cpu(ftrace_sync)
925 	 */
926 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
927 						 !preemptible());
928 
929 	if (ftrace_lookup_ip(notrace_hash, addr))
930 		ret = 1;
931 
932 	preempt_enable_notrace();
933 	return ret;
934 }
935 #else
936 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
937 {
938 	return 1;
939 }
940 
941 static inline int ftrace_graph_notrace_addr(unsigned long addr)
942 {
943 	return 0;
944 }
945 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
946 { }
947 #endif /* CONFIG_DYNAMIC_FTRACE */
948 
949 extern unsigned int fgraph_max_depth;
950 
951 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
952 {
953 	/* trace it when it is-nested-in or is a function enabled. */
954 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
955 		 ftrace_graph_addr(trace)) ||
956 		(trace->depth < 0) ||
957 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
958 }
959 
960 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
961 static inline enum print_line_t
962 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
963 {
964 	return TRACE_TYPE_UNHANDLED;
965 }
966 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
967 
968 extern struct list_head ftrace_pids;
969 
970 #ifdef CONFIG_FUNCTION_TRACER
971 
972 #define FTRACE_PID_IGNORE	-1
973 #define FTRACE_PID_TRACE	-2
974 
975 struct ftrace_func_command {
976 	struct list_head	list;
977 	char			*name;
978 	int			(*func)(struct trace_array *tr,
979 					struct ftrace_hash *hash,
980 					char *func, char *cmd,
981 					char *params, int enable);
982 };
983 extern bool ftrace_filter_param __initdata;
984 static inline int ftrace_trace_task(struct trace_array *tr)
985 {
986 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
987 		FTRACE_PID_IGNORE;
988 }
989 extern int ftrace_is_dead(void);
990 int ftrace_create_function_files(struct trace_array *tr,
991 				 struct dentry *parent);
992 void ftrace_destroy_function_files(struct trace_array *tr);
993 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
994 void ftrace_free_ftrace_ops(struct trace_array *tr);
995 void ftrace_init_global_array_ops(struct trace_array *tr);
996 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
997 void ftrace_reset_array_ops(struct trace_array *tr);
998 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
999 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1000 				  struct dentry *d_tracer);
1001 void ftrace_clear_pids(struct trace_array *tr);
1002 int init_function_trace(void);
1003 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1004 #else
1005 static inline int ftrace_trace_task(struct trace_array *tr)
1006 {
1007 	return 1;
1008 }
1009 static inline int ftrace_is_dead(void) { return 0; }
1010 static inline int
1011 ftrace_create_function_files(struct trace_array *tr,
1012 			     struct dentry *parent)
1013 {
1014 	return 0;
1015 }
1016 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1017 {
1018 	return 0;
1019 }
1020 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1021 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1022 static inline __init void
1023 ftrace_init_global_array_ops(struct trace_array *tr) { }
1024 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1025 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1026 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1027 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1028 static inline int init_function_trace(void) { return 0; }
1029 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1030 /* ftace_func_t type is not defined, use macro instead of static inline */
1031 #define ftrace_init_array_ops(tr, func) do { } while (0)
1032 #endif /* CONFIG_FUNCTION_TRACER */
1033 
1034 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1035 
1036 struct ftrace_probe_ops {
1037 	void			(*func)(unsigned long ip,
1038 					unsigned long parent_ip,
1039 					struct trace_array *tr,
1040 					struct ftrace_probe_ops *ops,
1041 					void *data);
1042 	int			(*init)(struct ftrace_probe_ops *ops,
1043 					struct trace_array *tr,
1044 					unsigned long ip, void *init_data,
1045 					void **data);
1046 	void			(*free)(struct ftrace_probe_ops *ops,
1047 					struct trace_array *tr,
1048 					unsigned long ip, void *data);
1049 	int			(*print)(struct seq_file *m,
1050 					 unsigned long ip,
1051 					 struct ftrace_probe_ops *ops,
1052 					 void *data);
1053 };
1054 
1055 struct ftrace_func_mapper;
1056 typedef int (*ftrace_mapper_func)(void *data);
1057 
1058 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1059 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1060 					   unsigned long ip);
1061 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1062 			       unsigned long ip, void *data);
1063 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1064 				   unsigned long ip);
1065 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1066 			     ftrace_mapper_func free_func);
1067 
1068 extern int
1069 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1070 			       struct ftrace_probe_ops *ops, void *data);
1071 extern int
1072 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1073 				      struct ftrace_probe_ops *ops);
1074 extern void clear_ftrace_function_probes(struct trace_array *tr);
1075 
1076 int register_ftrace_command(struct ftrace_func_command *cmd);
1077 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1078 
1079 void ftrace_create_filter_files(struct ftrace_ops *ops,
1080 				struct dentry *parent);
1081 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1082 
1083 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1084 			     int len, int reset);
1085 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1086 			      int len, int reset);
1087 #else
1088 struct ftrace_func_command;
1089 
1090 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1091 {
1092 	return -EINVAL;
1093 }
1094 static inline __init int unregister_ftrace_command(char *cmd_name)
1095 {
1096 	return -EINVAL;
1097 }
1098 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1099 {
1100 }
1101 
1102 /*
1103  * The ops parameter passed in is usually undefined.
1104  * This must be a macro.
1105  */
1106 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1107 #define ftrace_destroy_filter_files(ops) do { } while (0)
1108 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1109 
1110 bool ftrace_event_is_function(struct trace_event_call *call);
1111 
1112 /*
1113  * struct trace_parser - servers for reading the user input separated by spaces
1114  * @cont: set if the input is not complete - no final space char was found
1115  * @buffer: holds the parsed user input
1116  * @idx: user input length
1117  * @size: buffer size
1118  */
1119 struct trace_parser {
1120 	bool		cont;
1121 	char		*buffer;
1122 	unsigned	idx;
1123 	unsigned	size;
1124 };
1125 
1126 static inline bool trace_parser_loaded(struct trace_parser *parser)
1127 {
1128 	return (parser->idx != 0);
1129 }
1130 
1131 static inline bool trace_parser_cont(struct trace_parser *parser)
1132 {
1133 	return parser->cont;
1134 }
1135 
1136 static inline void trace_parser_clear(struct trace_parser *parser)
1137 {
1138 	parser->cont = false;
1139 	parser->idx = 0;
1140 }
1141 
1142 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1143 extern void trace_parser_put(struct trace_parser *parser);
1144 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1145 	size_t cnt, loff_t *ppos);
1146 
1147 /*
1148  * Only create function graph options if function graph is configured.
1149  */
1150 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1151 # define FGRAPH_FLAGS						\
1152 		C(DISPLAY_GRAPH,	"display-graph"),
1153 #else
1154 # define FGRAPH_FLAGS
1155 #endif
1156 
1157 #ifdef CONFIG_BRANCH_TRACER
1158 # define BRANCH_FLAGS					\
1159 		C(BRANCH,		"branch"),
1160 #else
1161 # define BRANCH_FLAGS
1162 #endif
1163 
1164 #ifdef CONFIG_FUNCTION_TRACER
1165 # define FUNCTION_FLAGS						\
1166 		C(FUNCTION,		"function-trace"),	\
1167 		C(FUNC_FORK,		"function-fork"),
1168 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1169 #else
1170 # define FUNCTION_FLAGS
1171 # define FUNCTION_DEFAULT_FLAGS		0UL
1172 # define TRACE_ITER_FUNC_FORK		0UL
1173 #endif
1174 
1175 #ifdef CONFIG_STACKTRACE
1176 # define STACK_FLAGS				\
1177 		C(STACKTRACE,		"stacktrace"),
1178 #else
1179 # define STACK_FLAGS
1180 #endif
1181 
1182 /*
1183  * trace_iterator_flags is an enumeration that defines bit
1184  * positions into trace_flags that controls the output.
1185  *
1186  * NOTE: These bits must match the trace_options array in
1187  *       trace.c (this macro guarantees it).
1188  */
1189 #define TRACE_FLAGS						\
1190 		C(PRINT_PARENT,		"print-parent"),	\
1191 		C(SYM_OFFSET,		"sym-offset"),		\
1192 		C(SYM_ADDR,		"sym-addr"),		\
1193 		C(VERBOSE,		"verbose"),		\
1194 		C(RAW,			"raw"),			\
1195 		C(HEX,			"hex"),			\
1196 		C(BIN,			"bin"),			\
1197 		C(BLOCK,		"block"),		\
1198 		C(PRINTK,		"trace_printk"),	\
1199 		C(ANNOTATE,		"annotate"),		\
1200 		C(USERSTACKTRACE,	"userstacktrace"),	\
1201 		C(SYM_USEROBJ,		"sym-userobj"),		\
1202 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1203 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1204 		C(LATENCY_FMT,		"latency-format"),	\
1205 		C(RECORD_CMD,		"record-cmd"),		\
1206 		C(RECORD_TGID,		"record-tgid"),		\
1207 		C(OVERWRITE,		"overwrite"),		\
1208 		C(STOP_ON_FREE,		"disable_on_free"),	\
1209 		C(IRQ_INFO,		"irq-info"),		\
1210 		C(MARKERS,		"markers"),		\
1211 		C(EVENT_FORK,		"event-fork"),		\
1212 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1213 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1214 		FUNCTION_FLAGS					\
1215 		FGRAPH_FLAGS					\
1216 		STACK_FLAGS					\
1217 		BRANCH_FLAGS
1218 
1219 /*
1220  * By defining C, we can make TRACE_FLAGS a list of bit names
1221  * that will define the bits for the flag masks.
1222  */
1223 #undef C
1224 #define C(a, b) TRACE_ITER_##a##_BIT
1225 
1226 enum trace_iterator_bits {
1227 	TRACE_FLAGS
1228 	/* Make sure we don't go more than we have bits for */
1229 	TRACE_ITER_LAST_BIT
1230 };
1231 
1232 /*
1233  * By redefining C, we can make TRACE_FLAGS a list of masks that
1234  * use the bits as defined above.
1235  */
1236 #undef C
1237 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1238 
1239 enum trace_iterator_flags { TRACE_FLAGS };
1240 
1241 /*
1242  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1243  * control the output of kernel symbols.
1244  */
1245 #define TRACE_ITER_SYM_MASK \
1246 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1247 
1248 extern struct tracer nop_trace;
1249 
1250 #ifdef CONFIG_BRANCH_TRACER
1251 extern int enable_branch_tracing(struct trace_array *tr);
1252 extern void disable_branch_tracing(void);
1253 static inline int trace_branch_enable(struct trace_array *tr)
1254 {
1255 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1256 		return enable_branch_tracing(tr);
1257 	return 0;
1258 }
1259 static inline void trace_branch_disable(void)
1260 {
1261 	/* due to races, always disable */
1262 	disable_branch_tracing();
1263 }
1264 #else
1265 static inline int trace_branch_enable(struct trace_array *tr)
1266 {
1267 	return 0;
1268 }
1269 static inline void trace_branch_disable(void)
1270 {
1271 }
1272 #endif /* CONFIG_BRANCH_TRACER */
1273 
1274 /* set ring buffers to default size if not already done so */
1275 int tracing_update_buffers(void);
1276 
1277 struct ftrace_event_field {
1278 	struct list_head	link;
1279 	const char		*name;
1280 	const char		*type;
1281 	int			filter_type;
1282 	int			offset;
1283 	int			size;
1284 	int			is_signed;
1285 };
1286 
1287 struct prog_entry;
1288 
1289 struct event_filter {
1290 	struct prog_entry __rcu	*prog;
1291 	char			*filter_string;
1292 };
1293 
1294 struct event_subsystem {
1295 	struct list_head	list;
1296 	const char		*name;
1297 	struct event_filter	*filter;
1298 	int			ref_count;
1299 };
1300 
1301 struct trace_subsystem_dir {
1302 	struct list_head		list;
1303 	struct event_subsystem		*subsystem;
1304 	struct trace_array		*tr;
1305 	struct dentry			*entry;
1306 	int				ref_count;
1307 	int				nr_events;
1308 };
1309 
1310 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1311 				     struct trace_buffer *buffer,
1312 				     struct ring_buffer_event *event);
1313 
1314 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1315 				     struct trace_buffer *buffer,
1316 				     struct ring_buffer_event *event,
1317 				     unsigned int trcace_ctx,
1318 				     struct pt_regs *regs);
1319 
1320 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1321 					      struct trace_buffer *buffer,
1322 					      struct ring_buffer_event *event,
1323 					      unsigned int trace_ctx)
1324 {
1325 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1326 }
1327 
1328 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1329 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1330 void trace_buffered_event_disable(void);
1331 void trace_buffered_event_enable(void);
1332 
1333 static inline void
1334 __trace_event_discard_commit(struct trace_buffer *buffer,
1335 			     struct ring_buffer_event *event)
1336 {
1337 	if (this_cpu_read(trace_buffered_event) == event) {
1338 		/* Simply release the temp buffer and enable preemption */
1339 		this_cpu_dec(trace_buffered_event_cnt);
1340 		preempt_enable_notrace();
1341 		return;
1342 	}
1343 	/* ring_buffer_discard_commit() enables preemption */
1344 	ring_buffer_discard_commit(buffer, event);
1345 }
1346 
1347 /*
1348  * Helper function for event_trigger_unlock_commit{_regs}().
1349  * If there are event triggers attached to this event that requires
1350  * filtering against its fields, then they will be called as the
1351  * entry already holds the field information of the current event.
1352  *
1353  * It also checks if the event should be discarded or not.
1354  * It is to be discarded if the event is soft disabled and the
1355  * event was only recorded to process triggers, or if the event
1356  * filter is active and this event did not match the filters.
1357  *
1358  * Returns true if the event is discarded, false otherwise.
1359  */
1360 static inline bool
1361 __event_trigger_test_discard(struct trace_event_file *file,
1362 			     struct trace_buffer *buffer,
1363 			     struct ring_buffer_event *event,
1364 			     void *entry,
1365 			     enum event_trigger_type *tt)
1366 {
1367 	unsigned long eflags = file->flags;
1368 
1369 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1370 		*tt = event_triggers_call(file, buffer, entry, event);
1371 
1372 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1373 				    EVENT_FILE_FL_FILTERED |
1374 				    EVENT_FILE_FL_PID_FILTER))))
1375 		return false;
1376 
1377 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1378 		goto discard;
1379 
1380 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1381 	    !filter_match_preds(file->filter, entry))
1382 		goto discard;
1383 
1384 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1385 	    trace_event_ignore_this_pid(file))
1386 		goto discard;
1387 
1388 	return false;
1389  discard:
1390 	__trace_event_discard_commit(buffer, event);
1391 	return true;
1392 }
1393 
1394 /**
1395  * event_trigger_unlock_commit - handle triggers and finish event commit
1396  * @file: The file pointer associated with the event
1397  * @buffer: The ring buffer that the event is being written to
1398  * @event: The event meta data in the ring buffer
1399  * @entry: The event itself
1400  * @trace_ctx: The tracing context flags.
1401  *
1402  * This is a helper function to handle triggers that require data
1403  * from the event itself. It also tests the event against filters and
1404  * if the event is soft disabled and should be discarded.
1405  */
1406 static inline void
1407 event_trigger_unlock_commit(struct trace_event_file *file,
1408 			    struct trace_buffer *buffer,
1409 			    struct ring_buffer_event *event,
1410 			    void *entry, unsigned int trace_ctx)
1411 {
1412 	enum event_trigger_type tt = ETT_NONE;
1413 
1414 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1415 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1416 
1417 	if (tt)
1418 		event_triggers_post_call(file, tt);
1419 }
1420 
1421 #define FILTER_PRED_INVALID	((unsigned short)-1)
1422 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1423 #define FILTER_PRED_FOLD	(1 << 15)
1424 
1425 /*
1426  * The max preds is the size of unsigned short with
1427  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1428  * and FOLD flags. The other is reserved.
1429  *
1430  * 2^14 preds is way more than enough.
1431  */
1432 #define MAX_FILTER_PRED		16384
1433 
1434 struct filter_pred;
1435 struct regex;
1436 
1437 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1438 
1439 enum regex_type {
1440 	MATCH_FULL = 0,
1441 	MATCH_FRONT_ONLY,
1442 	MATCH_MIDDLE_ONLY,
1443 	MATCH_END_ONLY,
1444 	MATCH_GLOB,
1445 	MATCH_INDEX,
1446 };
1447 
1448 struct regex {
1449 	char			pattern[MAX_FILTER_STR_VAL];
1450 	int			len;
1451 	int			field_len;
1452 	regex_match_func	match;
1453 };
1454 
1455 static inline bool is_string_field(struct ftrace_event_field *field)
1456 {
1457 	return field->filter_type == FILTER_DYN_STRING ||
1458 	       field->filter_type == FILTER_RDYN_STRING ||
1459 	       field->filter_type == FILTER_STATIC_STRING ||
1460 	       field->filter_type == FILTER_PTR_STRING ||
1461 	       field->filter_type == FILTER_COMM;
1462 }
1463 
1464 static inline bool is_function_field(struct ftrace_event_field *field)
1465 {
1466 	return field->filter_type == FILTER_TRACE_FN;
1467 }
1468 
1469 extern enum regex_type
1470 filter_parse_regex(char *buff, int len, char **search, int *not);
1471 extern void print_event_filter(struct trace_event_file *file,
1472 			       struct trace_seq *s);
1473 extern int apply_event_filter(struct trace_event_file *file,
1474 			      char *filter_string);
1475 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1476 					char *filter_string);
1477 extern void print_subsystem_event_filter(struct event_subsystem *system,
1478 					 struct trace_seq *s);
1479 extern int filter_assign_type(const char *type);
1480 extern int create_event_filter(struct trace_array *tr,
1481 			       struct trace_event_call *call,
1482 			       char *filter_str, bool set_str,
1483 			       struct event_filter **filterp);
1484 extern void free_event_filter(struct event_filter *filter);
1485 
1486 struct ftrace_event_field *
1487 trace_find_event_field(struct trace_event_call *call, char *name);
1488 
1489 extern void trace_event_enable_cmd_record(bool enable);
1490 extern void trace_event_enable_tgid_record(bool enable);
1491 
1492 extern int event_trace_init(void);
1493 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1494 extern int event_trace_del_tracer(struct trace_array *tr);
1495 extern void __trace_early_add_events(struct trace_array *tr);
1496 
1497 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1498 						  const char *system,
1499 						  const char *event);
1500 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1501 						const char *system,
1502 						const char *event);
1503 
1504 static inline void *event_file_data(struct file *filp)
1505 {
1506 	return READ_ONCE(file_inode(filp)->i_private);
1507 }
1508 
1509 extern struct mutex event_mutex;
1510 extern struct list_head ftrace_events;
1511 
1512 extern const struct file_operations event_trigger_fops;
1513 extern const struct file_operations event_hist_fops;
1514 extern const struct file_operations event_hist_debug_fops;
1515 extern const struct file_operations event_inject_fops;
1516 
1517 #ifdef CONFIG_HIST_TRIGGERS
1518 extern int register_trigger_hist_cmd(void);
1519 extern int register_trigger_hist_enable_disable_cmds(void);
1520 #else
1521 static inline int register_trigger_hist_cmd(void) { return 0; }
1522 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1523 #endif
1524 
1525 extern int register_trigger_cmds(void);
1526 extern void clear_event_triggers(struct trace_array *tr);
1527 
1528 enum {
1529 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1530 };
1531 
1532 struct event_trigger_data {
1533 	unsigned long			count;
1534 	int				ref;
1535 	int				flags;
1536 	struct event_trigger_ops	*ops;
1537 	struct event_command		*cmd_ops;
1538 	struct event_filter __rcu	*filter;
1539 	char				*filter_str;
1540 	void				*private_data;
1541 	bool				paused;
1542 	bool				paused_tmp;
1543 	struct list_head		list;
1544 	char				*name;
1545 	struct list_head		named_list;
1546 	struct event_trigger_data	*named_data;
1547 };
1548 
1549 /* Avoid typos */
1550 #define ENABLE_EVENT_STR	"enable_event"
1551 #define DISABLE_EVENT_STR	"disable_event"
1552 #define ENABLE_HIST_STR		"enable_hist"
1553 #define DISABLE_HIST_STR	"disable_hist"
1554 
1555 struct enable_trigger_data {
1556 	struct trace_event_file		*file;
1557 	bool				enable;
1558 	bool				hist;
1559 };
1560 
1561 extern int event_enable_trigger_print(struct seq_file *m,
1562 				      struct event_trigger_data *data);
1563 extern void event_enable_trigger_free(struct event_trigger_data *data);
1564 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1565 				      struct trace_event_file *file,
1566 				      char *glob, char *cmd,
1567 				      char *param_and_filter);
1568 extern int event_enable_register_trigger(char *glob,
1569 					 struct event_trigger_data *data,
1570 					 struct trace_event_file *file);
1571 extern void event_enable_unregister_trigger(char *glob,
1572 					    struct event_trigger_data *test,
1573 					    struct trace_event_file *file);
1574 extern void trigger_data_free(struct event_trigger_data *data);
1575 extern int event_trigger_init(struct event_trigger_data *data);
1576 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1577 					      int trigger_enable);
1578 extern void update_cond_flag(struct trace_event_file *file);
1579 extern int set_trigger_filter(char *filter_str,
1580 			      struct event_trigger_data *trigger_data,
1581 			      struct trace_event_file *file);
1582 extern struct event_trigger_data *find_named_trigger(const char *name);
1583 extern bool is_named_trigger(struct event_trigger_data *test);
1584 extern int save_named_trigger(const char *name,
1585 			      struct event_trigger_data *data);
1586 extern void del_named_trigger(struct event_trigger_data *data);
1587 extern void pause_named_trigger(struct event_trigger_data *data);
1588 extern void unpause_named_trigger(struct event_trigger_data *data);
1589 extern void set_named_trigger_data(struct event_trigger_data *data,
1590 				   struct event_trigger_data *named_data);
1591 extern struct event_trigger_data *
1592 get_named_trigger_data(struct event_trigger_data *data);
1593 extern int register_event_command(struct event_command *cmd);
1594 extern int unregister_event_command(struct event_command *cmd);
1595 extern int register_trigger_hist_enable_disable_cmds(void);
1596 extern bool event_trigger_check_remove(const char *glob);
1597 extern bool event_trigger_empty_param(const char *param);
1598 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1599 					 char **filter, bool param_required);
1600 extern struct event_trigger_data *
1601 event_trigger_alloc(struct event_command *cmd_ops,
1602 		    char *cmd,
1603 		    char *param,
1604 		    void *private_data);
1605 extern int event_trigger_parse_num(char *trigger,
1606 				   struct event_trigger_data *trigger_data);
1607 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1608 				    struct trace_event_file *file,
1609 				    char *param,
1610 				    struct event_trigger_data *trigger_data);
1611 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1612 				       struct event_trigger_data *trigger_data);
1613 extern int event_trigger_register(struct event_command *cmd_ops,
1614 				  struct trace_event_file *file,
1615 				  char *glob,
1616 				  struct event_trigger_data *trigger_data);
1617 extern void event_trigger_unregister(struct event_command *cmd_ops,
1618 				     struct trace_event_file *file,
1619 				     char *glob,
1620 				     struct event_trigger_data *trigger_data);
1621 
1622 /**
1623  * struct event_trigger_ops - callbacks for trace event triggers
1624  *
1625  * The methods in this structure provide per-event trigger hooks for
1626  * various trigger operations.
1627  *
1628  * The @init and @free methods are used during trigger setup and
1629  * teardown, typically called from an event_command's @parse()
1630  * function implementation.
1631  *
1632  * The @print method is used to print the trigger spec.
1633  *
1634  * The @trigger method is the function that actually implements the
1635  * trigger and is called in the context of the triggering event
1636  * whenever that event occurs.
1637  *
1638  * All the methods below, except for @init() and @free(), must be
1639  * implemented.
1640  *
1641  * @trigger: The trigger 'probe' function called when the triggering
1642  *	event occurs.  The data passed into this callback is the data
1643  *	that was supplied to the event_command @reg() function that
1644  *	registered the trigger (see struct event_command) along with
1645  *	the trace record, rec.
1646  *
1647  * @init: An optional initialization function called for the trigger
1648  *	when the trigger is registered (via the event_command reg()
1649  *	function).  This can be used to perform per-trigger
1650  *	initialization such as incrementing a per-trigger reference
1651  *	count, for instance.  This is usually implemented by the
1652  *	generic utility function @event_trigger_init() (see
1653  *	trace_event_triggers.c).
1654  *
1655  * @free: An optional de-initialization function called for the
1656  *	trigger when the trigger is unregistered (via the
1657  *	event_command @reg() function).  This can be used to perform
1658  *	per-trigger de-initialization such as decrementing a
1659  *	per-trigger reference count and freeing corresponding trigger
1660  *	data, for instance.  This is usually implemented by the
1661  *	generic utility function @event_trigger_free() (see
1662  *	trace_event_triggers.c).
1663  *
1664  * @print: The callback function invoked to have the trigger print
1665  *	itself.  This is usually implemented by a wrapper function
1666  *	that calls the generic utility function @event_trigger_print()
1667  *	(see trace_event_triggers.c).
1668  */
1669 struct event_trigger_ops {
1670 	void			(*trigger)(struct event_trigger_data *data,
1671 					   struct trace_buffer *buffer,
1672 					   void *rec,
1673 					   struct ring_buffer_event *rbe);
1674 	int			(*init)(struct event_trigger_data *data);
1675 	void			(*free)(struct event_trigger_data *data);
1676 	int			(*print)(struct seq_file *m,
1677 					 struct event_trigger_data *data);
1678 };
1679 
1680 /**
1681  * struct event_command - callbacks and data members for event commands
1682  *
1683  * Event commands are invoked by users by writing the command name
1684  * into the 'trigger' file associated with a trace event.  The
1685  * parameters associated with a specific invocation of an event
1686  * command are used to create an event trigger instance, which is
1687  * added to the list of trigger instances associated with that trace
1688  * event.  When the event is hit, the set of triggers associated with
1689  * that event is invoked.
1690  *
1691  * The data members in this structure provide per-event command data
1692  * for various event commands.
1693  *
1694  * All the data members below, except for @post_trigger, must be set
1695  * for each event command.
1696  *
1697  * @name: The unique name that identifies the event command.  This is
1698  *	the name used when setting triggers via trigger files.
1699  *
1700  * @trigger_type: A unique id that identifies the event command
1701  *	'type'.  This value has two purposes, the first to ensure that
1702  *	only one trigger of the same type can be set at a given time
1703  *	for a particular event e.g. it doesn't make sense to have both
1704  *	a traceon and traceoff trigger attached to a single event at
1705  *	the same time, so traceon and traceoff have the same type
1706  *	though they have different names.  The @trigger_type value is
1707  *	also used as a bit value for deferring the actual trigger
1708  *	action until after the current event is finished.  Some
1709  *	commands need to do this if they themselves log to the trace
1710  *	buffer (see the @post_trigger() member below).  @trigger_type
1711  *	values are defined by adding new values to the trigger_type
1712  *	enum in include/linux/trace_events.h.
1713  *
1714  * @flags: See the enum event_command_flags below.
1715  *
1716  * All the methods below, except for @set_filter() and @unreg_all(),
1717  * must be implemented.
1718  *
1719  * @parse: The callback function responsible for parsing and
1720  *	registering the trigger written to the 'trigger' file by the
1721  *	user.  It allocates the trigger instance and registers it with
1722  *	the appropriate trace event.  It makes use of the other
1723  *	event_command callback functions to orchestrate this, and is
1724  *	usually implemented by the generic utility function
1725  *	@event_trigger_callback() (see trace_event_triggers.c).
1726  *
1727  * @reg: Adds the trigger to the list of triggers associated with the
1728  *	event, and enables the event trigger itself, after
1729  *	initializing it (via the event_trigger_ops @init() function).
1730  *	This is also where commands can use the @trigger_type value to
1731  *	make the decision as to whether or not multiple instances of
1732  *	the trigger should be allowed.  This is usually implemented by
1733  *	the generic utility function @register_trigger() (see
1734  *	trace_event_triggers.c).
1735  *
1736  * @unreg: Removes the trigger from the list of triggers associated
1737  *	with the event, and disables the event trigger itself, after
1738  *	initializing it (via the event_trigger_ops @free() function).
1739  *	This is usually implemented by the generic utility function
1740  *	@unregister_trigger() (see trace_event_triggers.c).
1741  *
1742  * @unreg_all: An optional function called to remove all the triggers
1743  *	from the list of triggers associated with the event.  Called
1744  *	when a trigger file is opened in truncate mode.
1745  *
1746  * @set_filter: An optional function called to parse and set a filter
1747  *	for the trigger.  If no @set_filter() method is set for the
1748  *	event command, filters set by the user for the command will be
1749  *	ignored.  This is usually implemented by the generic utility
1750  *	function @set_trigger_filter() (see trace_event_triggers.c).
1751  *
1752  * @get_trigger_ops: The callback function invoked to retrieve the
1753  *	event_trigger_ops implementation associated with the command.
1754  *	This callback function allows a single event_command to
1755  *	support multiple trigger implementations via different sets of
1756  *	event_trigger_ops, depending on the value of the @param
1757  *	string.
1758  */
1759 struct event_command {
1760 	struct list_head	list;
1761 	char			*name;
1762 	enum event_trigger_type	trigger_type;
1763 	int			flags;
1764 	int			(*parse)(struct event_command *cmd_ops,
1765 					 struct trace_event_file *file,
1766 					 char *glob, char *cmd,
1767 					 char *param_and_filter);
1768 	int			(*reg)(char *glob,
1769 				       struct event_trigger_data *data,
1770 				       struct trace_event_file *file);
1771 	void			(*unreg)(char *glob,
1772 					 struct event_trigger_data *data,
1773 					 struct trace_event_file *file);
1774 	void			(*unreg_all)(struct trace_event_file *file);
1775 	int			(*set_filter)(char *filter_str,
1776 					      struct event_trigger_data *data,
1777 					      struct trace_event_file *file);
1778 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1779 };
1780 
1781 /**
1782  * enum event_command_flags - flags for struct event_command
1783  *
1784  * @POST_TRIGGER: A flag that says whether or not this command needs
1785  *	to have its action delayed until after the current event has
1786  *	been closed.  Some triggers need to avoid being invoked while
1787  *	an event is currently in the process of being logged, since
1788  *	the trigger may itself log data into the trace buffer.  Thus
1789  *	we make sure the current event is committed before invoking
1790  *	those triggers.  To do that, the trigger invocation is split
1791  *	in two - the first part checks the filter using the current
1792  *	trace record; if a command has the @post_trigger flag set, it
1793  *	sets a bit for itself in the return value, otherwise it
1794  *	directly invokes the trigger.  Once all commands have been
1795  *	either invoked or set their return flag, the current record is
1796  *	either committed or discarded.  At that point, if any commands
1797  *	have deferred their triggers, those commands are finally
1798  *	invoked following the close of the current event.  In other
1799  *	words, if the event_trigger_ops @func() probe implementation
1800  *	itself logs to the trace buffer, this flag should be set,
1801  *	otherwise it can be left unspecified.
1802  *
1803  * @NEEDS_REC: A flag that says whether or not this command needs
1804  *	access to the trace record in order to perform its function,
1805  *	regardless of whether or not it has a filter associated with
1806  *	it (filters make a trigger require access to the trace record
1807  *	but are not always present).
1808  */
1809 enum event_command_flags {
1810 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1811 	EVENT_CMD_FL_NEEDS_REC		= 2,
1812 };
1813 
1814 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1815 {
1816 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1817 }
1818 
1819 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1820 {
1821 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1822 }
1823 
1824 extern int trace_event_enable_disable(struct trace_event_file *file,
1825 				      int enable, int soft_disable);
1826 extern int tracing_alloc_snapshot(void);
1827 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1828 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1829 
1830 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1831 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1832 
1833 extern const char *__start___trace_bprintk_fmt[];
1834 extern const char *__stop___trace_bprintk_fmt[];
1835 
1836 extern const char *__start___tracepoint_str[];
1837 extern const char *__stop___tracepoint_str[];
1838 
1839 void trace_printk_control(bool enabled);
1840 void trace_printk_start_comm(void);
1841 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1842 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1843 
1844 /* Used from boot time tracer */
1845 extern int trace_set_options(struct trace_array *tr, char *option);
1846 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1847 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1848 					  unsigned long size, int cpu_id);
1849 extern int tracing_set_cpumask(struct trace_array *tr,
1850 				cpumask_var_t tracing_cpumask_new);
1851 
1852 
1853 #define MAX_EVENT_NAME_LEN	64
1854 
1855 extern ssize_t trace_parse_run_command(struct file *file,
1856 		const char __user *buffer, size_t count, loff_t *ppos,
1857 		int (*createfn)(const char *));
1858 
1859 extern unsigned int err_pos(char *cmd, const char *str);
1860 extern void tracing_log_err(struct trace_array *tr,
1861 			    const char *loc, const char *cmd,
1862 			    const char **errs, u8 type, u16 pos);
1863 
1864 /*
1865  * Normal trace_printk() and friends allocates special buffers
1866  * to do the manipulation, as well as saves the print formats
1867  * into sections to display. But the trace infrastructure wants
1868  * to use these without the added overhead at the price of being
1869  * a bit slower (used mainly for warnings, where we don't care
1870  * about performance). The internal_trace_puts() is for such
1871  * a purpose.
1872  */
1873 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1874 
1875 #undef FTRACE_ENTRY
1876 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1877 	extern struct trace_event_call					\
1878 	__aligned(4) event_##call;
1879 #undef FTRACE_ENTRY_DUP
1880 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1881 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1882 #undef FTRACE_ENTRY_PACKED
1883 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1884 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1885 
1886 #include "trace_entries.h"
1887 
1888 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1889 int perf_ftrace_event_register(struct trace_event_call *call,
1890 			       enum trace_reg type, void *data);
1891 #else
1892 #define perf_ftrace_event_register NULL
1893 #endif
1894 
1895 #ifdef CONFIG_FTRACE_SYSCALLS
1896 void init_ftrace_syscalls(void);
1897 const char *get_syscall_name(int syscall);
1898 #else
1899 static inline void init_ftrace_syscalls(void) { }
1900 static inline const char *get_syscall_name(int syscall)
1901 {
1902 	return NULL;
1903 }
1904 #endif
1905 
1906 #ifdef CONFIG_EVENT_TRACING
1907 void trace_event_init(void);
1908 void trace_event_eval_update(struct trace_eval_map **map, int len);
1909 /* Used from boot time tracer */
1910 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1911 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1912 #else
1913 static inline void __init trace_event_init(void) { }
1914 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1915 #endif
1916 
1917 #ifdef CONFIG_TRACER_SNAPSHOT
1918 void tracing_snapshot_instance(struct trace_array *tr);
1919 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1920 #else
1921 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1922 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1923 {
1924 	return 0;
1925 }
1926 #endif
1927 
1928 #ifdef CONFIG_PREEMPT_TRACER
1929 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1930 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1931 #else
1932 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1933 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1934 #endif
1935 #ifdef CONFIG_IRQSOFF_TRACER
1936 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1937 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1938 #else
1939 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1940 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1941 #endif
1942 
1943 /*
1944  * Reset the state of the trace_iterator so that it can read consumed data.
1945  * Normally, the trace_iterator is used for reading the data when it is not
1946  * consumed, and must retain state.
1947  */
1948 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1949 {
1950 	memset_startat(iter, 0, seq);
1951 	iter->pos = -1;
1952 }
1953 
1954 /* Check the name is good for event/group/fields */
1955 static inline bool __is_good_name(const char *name, bool hash_ok)
1956 {
1957 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
1958 		return false;
1959 	while (*++name != '\0') {
1960 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
1961 		    (!hash_ok || *name != '-'))
1962 			return false;
1963 	}
1964 	return true;
1965 }
1966 
1967 /* Check the name is good for event/group/fields */
1968 static inline bool is_good_name(const char *name)
1969 {
1970 	return __is_good_name(name, false);
1971 }
1972 
1973 /* Check the name is good for system */
1974 static inline bool is_good_system_name(const char *name)
1975 {
1976 	return __is_good_name(name, true);
1977 }
1978 
1979 /* Convert certain expected symbols into '_' when generating event names */
1980 static inline void sanitize_event_name(char *name)
1981 {
1982 	while (*name++ != '\0')
1983 		if (*name == ':' || *name == '.')
1984 			*name = '_';
1985 }
1986 
1987 /*
1988  * This is a generic way to read and write a u64 value from a file in tracefs.
1989  *
1990  * The value is stored on the variable pointed by *val. The value needs
1991  * to be at least *min and at most *max. The write is protected by an
1992  * existing *lock.
1993  */
1994 struct trace_min_max_param {
1995 	struct mutex	*lock;
1996 	u64		*val;
1997 	u64		*min;
1998 	u64		*max;
1999 };
2000 
2001 #define U64_STR_SIZE		24	/* 20 digits max */
2002 
2003 extern const struct file_operations trace_min_max_fops;
2004 
2005 #ifdef CONFIG_RV
2006 extern int rv_init_interface(void);
2007 #else
2008 static inline int rv_init_interface(void)
2009 {
2010 	return 0;
2011 }
2012 #endif
2013 
2014 #endif /* _LINUX_KERNEL_TRACE_H */
2015