xref: /linux-6.15/kernel/trace/trace.h (revision bcba8d4d)
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_GRAPH_RETADDR_ENT,
50 	TRACE_USER_STACK,
51 	TRACE_BLK,
52 	TRACE_BPUTS,
53 	TRACE_HWLAT,
54 	TRACE_OSNOISE,
55 	TRACE_TIMERLAT,
56 	TRACE_RAW_DATA,
57 	TRACE_FUNC_REPEATS,
58 
59 	__TRACE_LAST_TYPE,
60 };
61 
62 
63 #undef __field
64 #define __field(type, item)		type	item;
65 
66 #undef __field_fn
67 #define __field_fn(type, item)		type	item;
68 
69 #undef __field_struct
70 #define __field_struct(type, item)	__field(type, item)
71 
72 #undef __field_desc
73 #define __field_desc(type, container, item)
74 
75 #undef __field_packed
76 #define __field_packed(type, container, item)
77 
78 #undef __array
79 #define __array(type, item, size)	type	item[size];
80 
81 /*
82  * For backward compatibility, older user space expects to see the
83  * kernel_stack event with a fixed size caller field. But today the fix
84  * size is ignored by the kernel, and the real structure is dynamic.
85  * Expose to user space: "unsigned long caller[8];" but the real structure
86  * will be "unsigned long caller[] __counted_by(size)"
87  */
88 #undef __stack_array
89 #define __stack_array(type, item, size, field)		type item[] __counted_by(field);
90 
91 #undef __array_desc
92 #define __array_desc(type, container, item, size)
93 
94 #undef __dynamic_array
95 #define __dynamic_array(type, item)	type	item[];
96 
97 #undef __rel_dynamic_array
98 #define __rel_dynamic_array(type, item)	type	item[];
99 
100 #undef F_STRUCT
101 #define F_STRUCT(args...)		args
102 
103 #undef FTRACE_ENTRY
104 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
105 	struct struct_name {						\
106 		struct trace_entry	ent;				\
107 		tstruct							\
108 	}
109 
110 #undef FTRACE_ENTRY_DUP
111 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
112 
113 #undef FTRACE_ENTRY_REG
114 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
115 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
116 
117 #undef FTRACE_ENTRY_PACKED
118 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
119 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
120 
121 #include "trace_entries.h"
122 
123 /* Use this for memory failure errors */
124 #define MEM_FAIL(condition, fmt, ...)					\
125 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
126 
127 #define FAULT_STRING "(fault)"
128 
129 #define HIST_STACKTRACE_DEPTH	16
130 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
131 #define HIST_STACKTRACE_SKIP	5
132 
133 /*
134  * syscalls are special, and need special handling, this is why
135  * they are not included in trace_entries.h
136  */
137 struct syscall_trace_enter {
138 	struct trace_entry	ent;
139 	int			nr;
140 	unsigned long		args[];
141 };
142 
143 struct syscall_trace_exit {
144 	struct trace_entry	ent;
145 	int			nr;
146 	long			ret;
147 };
148 
149 struct kprobe_trace_entry_head {
150 	struct trace_entry	ent;
151 	unsigned long		ip;
152 };
153 
154 struct eprobe_trace_entry_head {
155 	struct trace_entry	ent;
156 };
157 
158 struct kretprobe_trace_entry_head {
159 	struct trace_entry	ent;
160 	unsigned long		func;
161 	unsigned long		ret_ip;
162 };
163 
164 struct fentry_trace_entry_head {
165 	struct trace_entry	ent;
166 	unsigned long		ip;
167 };
168 
169 struct fexit_trace_entry_head {
170 	struct trace_entry	ent;
171 	unsigned long		func;
172 	unsigned long		ret_ip;
173 };
174 
175 #define TRACE_BUF_SIZE		1024
176 
177 struct trace_array;
178 
179 /*
180  * The CPU trace array - it consists of thousands of trace entries
181  * plus some other descriptor data: (for example which task started
182  * the trace, etc.)
183  */
184 struct trace_array_cpu {
185 	atomic_t		disabled;
186 	void			*buffer_page;	/* ring buffer spare */
187 
188 	unsigned long		entries;
189 	unsigned long		saved_latency;
190 	unsigned long		critical_start;
191 	unsigned long		critical_end;
192 	unsigned long		critical_sequence;
193 	unsigned long		nice;
194 	unsigned long		policy;
195 	unsigned long		rt_priority;
196 	unsigned long		skipped_entries;
197 	u64			preempt_timestamp;
198 	pid_t			pid;
199 	kuid_t			uid;
200 	char			comm[TASK_COMM_LEN];
201 
202 #ifdef CONFIG_FUNCTION_TRACER
203 	int			ftrace_ignore_pid;
204 #endif
205 	bool			ignore_pid;
206 };
207 
208 struct tracer;
209 struct trace_option_dentry;
210 
211 struct array_buffer {
212 	struct trace_array		*tr;
213 	struct trace_buffer		*buffer;
214 	struct trace_array_cpu __percpu	*data;
215 	u64				time_start;
216 	int				cpu;
217 };
218 
219 #define TRACE_FLAGS_MAX_SIZE		32
220 
221 struct trace_options {
222 	struct tracer			*tracer;
223 	struct trace_option_dentry	*topts;
224 };
225 
226 struct trace_pid_list *trace_pid_list_alloc(void);
227 void trace_pid_list_free(struct trace_pid_list *pid_list);
228 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
229 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
231 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
232 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
233 			unsigned int *next);
234 
235 enum {
236 	TRACE_PIDS		= BIT(0),
237 	TRACE_NO_PIDS		= BIT(1),
238 };
239 
240 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
241 				    struct trace_pid_list *no_pid_list)
242 {
243 	/* Return true if the pid list in type has pids */
244 	return ((type & TRACE_PIDS) && pid_list) ||
245 		((type & TRACE_NO_PIDS) && no_pid_list);
246 }
247 
248 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
249 					 struct trace_pid_list *no_pid_list)
250 {
251 	/*
252 	 * Turning off what is in @type, return true if the "other"
253 	 * pid list, still has pids in it.
254 	 */
255 	return (!(type & TRACE_PIDS) && pid_list) ||
256 		(!(type & TRACE_NO_PIDS) && no_pid_list);
257 }
258 
259 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
260 
261 /**
262  * struct cond_snapshot - conditional snapshot data and callback
263  *
264  * The cond_snapshot structure encapsulates a callback function and
265  * data associated with the snapshot for a given tracing instance.
266  *
267  * When a snapshot is taken conditionally, by invoking
268  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
269  * passed in turn to the cond_snapshot.update() function.  That data
270  * can be compared by the update() implementation with the cond_data
271  * contained within the struct cond_snapshot instance associated with
272  * the trace_array.  Because the tr->max_lock is held throughout the
273  * update() call, the update() function can directly retrieve the
274  * cond_snapshot and cond_data associated with the per-instance
275  * snapshot associated with the trace_array.
276  *
277  * The cond_snapshot.update() implementation can save data to be
278  * associated with the snapshot if it decides to, and returns 'true'
279  * in that case, or it returns 'false' if the conditional snapshot
280  * shouldn't be taken.
281  *
282  * The cond_snapshot instance is created and associated with the
283  * user-defined cond_data by tracing_cond_snapshot_enable().
284  * Likewise, the cond_snapshot instance is destroyed and is no longer
285  * associated with the trace instance by
286  * tracing_cond_snapshot_disable().
287  *
288  * The method below is required.
289  *
290  * @update: When a conditional snapshot is invoked, the update()
291  *	callback function is invoked with the tr->max_lock held.  The
292  *	update() implementation signals whether or not to actually
293  *	take the snapshot, by returning 'true' if so, 'false' if no
294  *	snapshot should be taken.  Because the max_lock is held for
295  *	the duration of update(), the implementation is safe to
296  *	directly retrieved and save any implementation data it needs
297  *	to in association with the snapshot.
298  */
299 struct cond_snapshot {
300 	void				*cond_data;
301 	cond_update_fn_t		update;
302 };
303 
304 /*
305  * struct trace_func_repeats - used to keep track of the consecutive
306  * (on the same CPU) calls of a single function.
307  */
308 struct trace_func_repeats {
309 	unsigned long	ip;
310 	unsigned long	parent_ip;
311 	unsigned long	count;
312 	u64		ts_last_call;
313 };
314 
315 /*
316  * The trace array - an array of per-CPU trace arrays. This is the
317  * highest level data structure that individual tracers deal with.
318  * They have on/off state as well:
319  */
320 struct trace_array {
321 	struct list_head	list;
322 	char			*name;
323 	struct array_buffer	array_buffer;
324 #ifdef CONFIG_TRACER_MAX_TRACE
325 	/*
326 	 * The max_buffer is used to snapshot the trace when a maximum
327 	 * latency is reached, or when the user initiates a snapshot.
328 	 * Some tracers will use this to store a maximum trace while
329 	 * it continues examining live traces.
330 	 *
331 	 * The buffers for the max_buffer are set up the same as the array_buffer
332 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
333 	 * with the buffer of the array_buffer and the buffers are reset for
334 	 * the array_buffer so the tracing can continue.
335 	 */
336 	struct array_buffer	max_buffer;
337 	bool			allocated_snapshot;
338 	spinlock_t		snapshot_trigger_lock;
339 	unsigned int		snapshot;
340 	unsigned long		max_latency;
341 #ifdef CONFIG_FSNOTIFY
342 	struct dentry		*d_max_latency;
343 	struct work_struct	fsnotify_work;
344 	struct irq_work		fsnotify_irqwork;
345 #endif
346 #endif
347 	/* The below is for memory mapped ring buffer */
348 	unsigned int		mapped;
349 	unsigned long		range_addr_start;
350 	unsigned long		range_addr_size;
351 	unsigned long		kaslr_addr;
352 	long			text_delta;
353 
354 	struct trace_pid_list	__rcu *filtered_pids;
355 	struct trace_pid_list	__rcu *filtered_no_pids;
356 	/*
357 	 * max_lock is used to protect the swapping of buffers
358 	 * when taking a max snapshot. The buffers themselves are
359 	 * protected by per_cpu spinlocks. But the action of the swap
360 	 * needs its own lock.
361 	 *
362 	 * This is defined as a arch_spinlock_t in order to help
363 	 * with performance when lockdep debugging is enabled.
364 	 *
365 	 * It is also used in other places outside the update_max_tr
366 	 * so it needs to be defined outside of the
367 	 * CONFIG_TRACER_MAX_TRACE.
368 	 */
369 	arch_spinlock_t		max_lock;
370 	int			buffer_disabled;
371 #ifdef CONFIG_FTRACE_SYSCALLS
372 	int			sys_refcount_enter;
373 	int			sys_refcount_exit;
374 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
375 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
376 #endif
377 	int			stop_count;
378 	int			clock_id;
379 	int			nr_topts;
380 	bool			clear_trace;
381 	int			buffer_percent;
382 	unsigned int		n_err_log_entries;
383 	struct tracer		*current_trace;
384 	unsigned int		trace_flags;
385 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
386 	unsigned int		flags;
387 	raw_spinlock_t		start_lock;
388 	const char		*system_names;
389 	struct list_head	err_log;
390 	struct dentry		*dir;
391 	struct dentry		*options;
392 	struct dentry		*percpu_dir;
393 	struct eventfs_inode	*event_dir;
394 	struct trace_options	*topts;
395 	struct list_head	systems;
396 	struct list_head	events;
397 	struct trace_event_file *trace_marker_file;
398 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
399 	/* one per_cpu trace_pipe can be opened by only one user */
400 	cpumask_var_t		pipe_cpumask;
401 	int			ref;
402 	int			trace_ref;
403 #ifdef CONFIG_MODULES
404 	struct list_head	mod_events;
405 #endif
406 #ifdef CONFIG_FUNCTION_TRACER
407 	struct ftrace_ops	*ops;
408 	struct trace_pid_list	__rcu *function_pids;
409 	struct trace_pid_list	__rcu *function_no_pids;
410 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
411 	struct fgraph_ops	*gops;
412 #endif
413 #ifdef CONFIG_DYNAMIC_FTRACE
414 	/* All of these are protected by the ftrace_lock */
415 	struct list_head	func_probes;
416 	struct list_head	mod_trace;
417 	struct list_head	mod_notrace;
418 #endif
419 	/* function tracing enabled */
420 	int			function_enabled;
421 #endif
422 	int			no_filter_buffering_ref;
423 	struct list_head	hist_vars;
424 #ifdef CONFIG_TRACER_SNAPSHOT
425 	struct cond_snapshot	*cond_snapshot;
426 #endif
427 	struct trace_func_repeats	__percpu *last_func_repeats;
428 	/*
429 	 * On boot up, the ring buffer is set to the minimum size, so that
430 	 * we do not waste memory on systems that are not using tracing.
431 	 */
432 	bool ring_buffer_expanded;
433 };
434 
435 enum {
436 	TRACE_ARRAY_FL_GLOBAL		= BIT(0),
437 	TRACE_ARRAY_FL_BOOT		= BIT(1),
438 	TRACE_ARRAY_FL_LAST_BOOT	= BIT(2),
439 	TRACE_ARRAY_FL_MOD_INIT		= BIT(3),
440 };
441 
442 #ifdef CONFIG_MODULES
443 bool module_exists(const char *module);
444 #else
445 static inline bool module_exists(const char *module)
446 {
447 	return false;
448 }
449 #endif
450 
451 extern struct list_head ftrace_trace_arrays;
452 
453 extern struct mutex trace_types_lock;
454 
455 extern int trace_array_get(struct trace_array *tr);
456 extern int tracing_check_open_get_tr(struct trace_array *tr);
457 extern struct trace_array *trace_array_find(const char *instance);
458 extern struct trace_array *trace_array_find_get(const char *instance);
459 
460 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
461 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
462 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
463 
464 extern bool trace_clock_in_ns(struct trace_array *tr);
465 
466 /*
467  * The global tracer (top) should be the first trace array added,
468  * but we check the flag anyway.
469  */
470 static inline struct trace_array *top_trace_array(void)
471 {
472 	struct trace_array *tr;
473 
474 	if (list_empty(&ftrace_trace_arrays))
475 		return NULL;
476 
477 	tr = list_entry(ftrace_trace_arrays.prev,
478 			typeof(*tr), list);
479 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
480 	return tr;
481 }
482 
483 #define FTRACE_CMP_TYPE(var, type) \
484 	__builtin_types_compatible_p(typeof(var), type *)
485 
486 #undef IF_ASSIGN
487 #define IF_ASSIGN(var, entry, etype, id)			\
488 	if (FTRACE_CMP_TYPE(var, etype)) {			\
489 		var = (typeof(var))(entry);			\
490 		WARN_ON(id != 0 && (entry)->type != id);	\
491 		break;						\
492 	}
493 
494 /* Will cause compile errors if type is not found. */
495 extern void __ftrace_bad_type(void);
496 
497 /*
498  * The trace_assign_type is a verifier that the entry type is
499  * the same as the type being assigned. To add new types simply
500  * add a line with the following format:
501  *
502  * IF_ASSIGN(var, ent, type, id);
503  *
504  *  Where "type" is the trace type that includes the trace_entry
505  *  as the "ent" item. And "id" is the trace identifier that is
506  *  used in the trace_type enum.
507  *
508  *  If the type can have more than one id, then use zero.
509  */
510 #define trace_assign_type(var, ent)					\
511 	do {								\
512 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
513 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
514 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
515 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
516 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
517 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
518 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
519 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
520 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
521 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
522 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
523 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
524 			  TRACE_MMIO_RW);				\
525 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
526 			  TRACE_MMIO_MAP);				\
527 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
528 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
529 			  TRACE_GRAPH_ENT);		\
530 		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
531 			  TRACE_GRAPH_RETADDR_ENT);		\
532 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
533 			  TRACE_GRAPH_RET);		\
534 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
535 			  TRACE_FUNC_REPEATS);				\
536 		__ftrace_bad_type();					\
537 	} while (0)
538 
539 /*
540  * An option specific to a tracer. This is a boolean value.
541  * The bit is the bit index that sets its value on the
542  * flags value in struct tracer_flags.
543  */
544 struct tracer_opt {
545 	const char	*name; /* Will appear on the trace_options file */
546 	u32		bit; /* Mask assigned in val field in tracer_flags */
547 };
548 
549 /*
550  * The set of specific options for a tracer. Your tracer
551  * have to set the initial value of the flags val.
552  */
553 struct tracer_flags {
554 	u32			val;
555 	struct tracer_opt	*opts;
556 	struct tracer		*trace;
557 };
558 
559 /* Makes more easy to define a tracer opt */
560 #define TRACER_OPT(s, b)	.name = #s, .bit = b
561 
562 
563 struct trace_option_dentry {
564 	struct tracer_opt		*opt;
565 	struct tracer_flags		*flags;
566 	struct trace_array		*tr;
567 	struct dentry			*entry;
568 };
569 
570 /**
571  * struct tracer - a specific tracer and its callbacks to interact with tracefs
572  * @name: the name chosen to select it on the available_tracers file
573  * @init: called when one switches to this tracer (echo name > current_tracer)
574  * @reset: called when one switches to another tracer
575  * @start: called when tracing is unpaused (echo 1 > tracing_on)
576  * @stop: called when tracing is paused (echo 0 > tracing_on)
577  * @update_thresh: called when tracing_thresh is updated
578  * @open: called when the trace file is opened
579  * @pipe_open: called when the trace_pipe file is opened
580  * @close: called when the trace file is released
581  * @pipe_close: called when the trace_pipe file is released
582  * @read: override the default read callback on trace_pipe
583  * @splice_read: override the default splice_read callback on trace_pipe
584  * @selftest: selftest to run on boot (see trace_selftest.c)
585  * @print_headers: override the first lines that describe your columns
586  * @print_line: callback that prints a trace
587  * @set_flag: signals one of your private flags changed (trace_options file)
588  * @flags: your private flags
589  */
590 struct tracer {
591 	const char		*name;
592 	int			(*init)(struct trace_array *tr);
593 	void			(*reset)(struct trace_array *tr);
594 	void			(*start)(struct trace_array *tr);
595 	void			(*stop)(struct trace_array *tr);
596 	int			(*update_thresh)(struct trace_array *tr);
597 	void			(*open)(struct trace_iterator *iter);
598 	void			(*pipe_open)(struct trace_iterator *iter);
599 	void			(*close)(struct trace_iterator *iter);
600 	void			(*pipe_close)(struct trace_iterator *iter);
601 	ssize_t			(*read)(struct trace_iterator *iter,
602 					struct file *filp, char __user *ubuf,
603 					size_t cnt, loff_t *ppos);
604 	ssize_t			(*splice_read)(struct trace_iterator *iter,
605 					       struct file *filp,
606 					       loff_t *ppos,
607 					       struct pipe_inode_info *pipe,
608 					       size_t len,
609 					       unsigned int flags);
610 #ifdef CONFIG_FTRACE_STARTUP_TEST
611 	int			(*selftest)(struct tracer *trace,
612 					    struct trace_array *tr);
613 #endif
614 	void			(*print_header)(struct seq_file *m);
615 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
616 	/* If you handled the flag setting, return 0 */
617 	int			(*set_flag)(struct trace_array *tr,
618 					    u32 old_flags, u32 bit, int set);
619 	/* Return 0 if OK with change, else return non-zero */
620 	int			(*flag_changed)(struct trace_array *tr,
621 						u32 mask, int set);
622 	struct tracer		*next;
623 	struct tracer_flags	*flags;
624 	int			enabled;
625 	bool			print_max;
626 	bool			allow_instances;
627 #ifdef CONFIG_TRACER_MAX_TRACE
628 	bool			use_max_tr;
629 #endif
630 	/* True if tracer cannot be enabled in kernel param */
631 	bool			noboot;
632 };
633 
634 static inline struct ring_buffer_iter *
635 trace_buffer_iter(struct trace_iterator *iter, int cpu)
636 {
637 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
638 }
639 
640 int tracer_init(struct tracer *t, struct trace_array *tr);
641 int tracing_is_enabled(void);
642 void tracing_reset_online_cpus(struct array_buffer *buf);
643 void tracing_reset_all_online_cpus(void);
644 void tracing_reset_all_online_cpus_unlocked(void);
645 int tracing_open_generic(struct inode *inode, struct file *filp);
646 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
647 int tracing_release_generic_tr(struct inode *inode, struct file *file);
648 int tracing_open_file_tr(struct inode *inode, struct file *filp);
649 int tracing_release_file_tr(struct inode *inode, struct file *filp);
650 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
651 bool tracing_is_disabled(void);
652 bool tracer_tracing_is_on(struct trace_array *tr);
653 void tracer_tracing_on(struct trace_array *tr);
654 void tracer_tracing_off(struct trace_array *tr);
655 struct dentry *trace_create_file(const char *name,
656 				 umode_t mode,
657 				 struct dentry *parent,
658 				 void *data,
659 				 const struct file_operations *fops);
660 
661 int tracing_init_dentry(void);
662 
663 struct ring_buffer_event;
664 
665 struct ring_buffer_event *
666 trace_buffer_lock_reserve(struct trace_buffer *buffer,
667 			  int type,
668 			  unsigned long len,
669 			  unsigned int trace_ctx);
670 
671 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
672 
673 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
674 						struct trace_array_cpu *data);
675 
676 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
677 					  int *ent_cpu, u64 *ent_ts);
678 
679 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
680 					struct ring_buffer_event *event);
681 
682 bool trace_is_tracepoint_string(const char *str);
683 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
684 char *trace_iter_expand_format(struct trace_iterator *iter);
685 bool ignore_event(struct trace_iterator *iter);
686 
687 int trace_empty(struct trace_iterator *iter);
688 
689 void *trace_find_next_entry_inc(struct trace_iterator *iter);
690 
691 void trace_init_global_iter(struct trace_iterator *iter);
692 
693 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
694 
695 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
696 unsigned long trace_total_entries(struct trace_array *tr);
697 
698 void trace_function(struct trace_array *tr,
699 		    unsigned long ip,
700 		    unsigned long parent_ip,
701 		    unsigned int trace_ctx);
702 void trace_graph_function(struct trace_array *tr,
703 		    unsigned long ip,
704 		    unsigned long parent_ip,
705 		    unsigned int trace_ctx);
706 void trace_latency_header(struct seq_file *m);
707 void trace_default_header(struct seq_file *m);
708 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
709 
710 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
711 			struct ftrace_regs *fregs);
712 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
713 		      struct ftrace_regs *fregs);
714 
715 void tracing_start_cmdline_record(void);
716 void tracing_stop_cmdline_record(void);
717 void tracing_start_tgid_record(void);
718 void tracing_stop_tgid_record(void);
719 
720 int register_tracer(struct tracer *type);
721 int is_tracing_stopped(void);
722 
723 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
724 
725 extern cpumask_var_t __read_mostly tracing_buffer_mask;
726 
727 #define for_each_tracing_cpu(cpu)	\
728 	for_each_cpu(cpu, tracing_buffer_mask)
729 
730 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
731 
732 extern unsigned long tracing_thresh;
733 
734 /* PID filtering */
735 
736 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
737 			     pid_t search_pid);
738 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
739 			    struct trace_pid_list *filtered_no_pids,
740 			    struct task_struct *task);
741 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
742 				  struct task_struct *self,
743 				  struct task_struct *task);
744 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
745 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
746 int trace_pid_show(struct seq_file *m, void *v);
747 int trace_pid_write(struct trace_pid_list *filtered_pids,
748 		    struct trace_pid_list **new_pid_list,
749 		    const char __user *ubuf, size_t cnt);
750 
751 #ifdef CONFIG_TRACER_MAX_TRACE
752 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
753 		   void *cond_data);
754 void update_max_tr_single(struct trace_array *tr,
755 			  struct task_struct *tsk, int cpu);
756 
757 #ifdef CONFIG_FSNOTIFY
758 #define LATENCY_FS_NOTIFY
759 #endif
760 #endif /* CONFIG_TRACER_MAX_TRACE */
761 
762 #ifdef LATENCY_FS_NOTIFY
763 void latency_fsnotify(struct trace_array *tr);
764 #else
765 static inline void latency_fsnotify(struct trace_array *tr) { }
766 #endif
767 
768 #ifdef CONFIG_STACKTRACE
769 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
770 #else
771 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
772 				 int skip)
773 {
774 }
775 #endif /* CONFIG_STACKTRACE */
776 
777 void trace_last_func_repeats(struct trace_array *tr,
778 			     struct trace_func_repeats *last_info,
779 			     unsigned int trace_ctx);
780 
781 extern u64 ftrace_now(int cpu);
782 
783 extern void trace_find_cmdline(int pid, char comm[]);
784 extern int trace_find_tgid(int pid);
785 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
786 
787 #ifdef CONFIG_DYNAMIC_FTRACE
788 extern unsigned long ftrace_update_tot_cnt;
789 extern unsigned long ftrace_number_of_pages;
790 extern unsigned long ftrace_number_of_groups;
791 extern u64 ftrace_update_time;
792 extern u64 ftrace_total_mod_time;
793 void ftrace_init_trace_array(struct trace_array *tr);
794 #else
795 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
796 #endif
797 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
798 extern int DYN_FTRACE_TEST_NAME(void);
799 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
800 extern int DYN_FTRACE_TEST_NAME2(void);
801 
802 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
803 extern bool tracing_selftest_disabled;
804 
805 #ifdef CONFIG_FTRACE_STARTUP_TEST
806 extern void __init disable_tracing_selftest(const char *reason);
807 
808 extern int trace_selftest_startup_function(struct tracer *trace,
809 					   struct trace_array *tr);
810 extern int trace_selftest_startup_function_graph(struct tracer *trace,
811 						 struct trace_array *tr);
812 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
813 					  struct trace_array *tr);
814 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
815 					     struct trace_array *tr);
816 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
817 						 struct trace_array *tr);
818 extern int trace_selftest_startup_wakeup(struct tracer *trace,
819 					 struct trace_array *tr);
820 extern int trace_selftest_startup_nop(struct tracer *trace,
821 					 struct trace_array *tr);
822 extern int trace_selftest_startup_branch(struct tracer *trace,
823 					 struct trace_array *tr);
824 /*
825  * Tracer data references selftest functions that only occur
826  * on boot up. These can be __init functions. Thus, when selftests
827  * are enabled, then the tracers need to reference __init functions.
828  */
829 #define __tracer_data		__refdata
830 #else
831 static inline void __init disable_tracing_selftest(const char *reason)
832 {
833 }
834 /* Tracers are seldom changed. Optimize when selftests are disabled. */
835 #define __tracer_data		__read_mostly
836 #endif /* CONFIG_FTRACE_STARTUP_TEST */
837 
838 extern void *head_page(struct trace_array_cpu *data);
839 extern unsigned long long ns2usecs(u64 nsec);
840 extern int
841 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
842 extern int
843 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
844 extern int
845 trace_array_vprintk(struct trace_array *tr,
846 		    unsigned long ip, const char *fmt, va_list args);
847 int trace_array_printk_buf(struct trace_buffer *buffer,
848 			   unsigned long ip, const char *fmt, ...);
849 void trace_printk_seq(struct trace_seq *s);
850 enum print_line_t print_trace_line(struct trace_iterator *iter);
851 
852 extern char trace_find_mark(unsigned long long duration);
853 
854 struct ftrace_hash;
855 
856 struct ftrace_mod_load {
857 	struct list_head	list;
858 	char			*func;
859 	char			*module;
860 	int			 enable;
861 };
862 
863 enum {
864 	FTRACE_HASH_FL_MOD	= (1 << 0),
865 };
866 
867 struct ftrace_hash {
868 	unsigned long		size_bits;
869 	struct hlist_head	*buckets;
870 	unsigned long		count;
871 	unsigned long		flags;
872 	struct rcu_head		rcu;
873 };
874 
875 struct ftrace_func_entry *
876 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
877 
878 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
879 {
880 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
881 }
882 
883 /* Standard output formatting function used for function return traces */
884 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
885 
886 /* Flag options */
887 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
888 #define TRACE_GRAPH_PRINT_CPU           0x2
889 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
890 #define TRACE_GRAPH_PRINT_PROC          0x8
891 #define TRACE_GRAPH_PRINT_DURATION      0x10
892 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
893 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
894 #define TRACE_GRAPH_PRINT_IRQS          0x80
895 #define TRACE_GRAPH_PRINT_TAIL          0x100
896 #define TRACE_GRAPH_SLEEP_TIME          0x200
897 #define TRACE_GRAPH_GRAPH_TIME          0x400
898 #define TRACE_GRAPH_PRINT_RETVAL        0x800
899 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
900 #define TRACE_GRAPH_PRINT_RETADDR       0x2000
901 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
902 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
903 
904 extern void ftrace_graph_sleep_time_control(bool enable);
905 
906 #ifdef CONFIG_FUNCTION_PROFILER
907 extern void ftrace_graph_graph_time_control(bool enable);
908 #else
909 static inline void ftrace_graph_graph_time_control(bool enable) { }
910 #endif
911 
912 extern enum print_line_t
913 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
914 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
915 extern void
916 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
917 extern void graph_trace_open(struct trace_iterator *iter);
918 extern void graph_trace_close(struct trace_iterator *iter);
919 extern int __trace_graph_entry(struct trace_array *tr,
920 			       struct ftrace_graph_ent *trace,
921 			       unsigned int trace_ctx);
922 extern int __trace_graph_retaddr_entry(struct trace_array *tr,
923 				struct ftrace_graph_ent *trace,
924 				unsigned int trace_ctx,
925 				unsigned long retaddr);
926 extern void __trace_graph_return(struct trace_array *tr,
927 				 struct ftrace_graph_ret *trace,
928 				 unsigned int trace_ctx,
929 				 u64 calltime, u64 rettime);
930 
931 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
932 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
933 extern void free_fgraph_ops(struct trace_array *tr);
934 
935 enum {
936 	TRACE_GRAPH_FL		= 1,
937 
938 	/*
939 	 * In the very unlikely case that an interrupt came in
940 	 * at a start of graph tracing, and we want to trace
941 	 * the function in that interrupt, the depth can be greater
942 	 * than zero, because of the preempted start of a previous
943 	 * trace. In an even more unlikely case, depth could be 2
944 	 * if a softirq interrupted the start of graph tracing,
945 	 * followed by an interrupt preempting a start of graph
946 	 * tracing in the softirq, and depth can even be 3
947 	 * if an NMI came in at the start of an interrupt function
948 	 * that preempted a softirq start of a function that
949 	 * preempted normal context!!!! Luckily, it can't be
950 	 * greater than 3, so the next two bits are a mask
951 	 * of what the depth is when we set TRACE_GRAPH_FL
952 	 */
953 
954 	TRACE_GRAPH_DEPTH_START_BIT,
955 	TRACE_GRAPH_DEPTH_END_BIT,
956 
957 	/*
958 	 * To implement set_graph_notrace, if this bit is set, we ignore
959 	 * function graph tracing of called functions, until the return
960 	 * function is called to clear it.
961 	 */
962 	TRACE_GRAPH_NOTRACE_BIT,
963 };
964 
965 #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
966 
967 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
968 {
969 	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
970 }
971 
972 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
973 {
974 	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
975 	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
976 }
977 
978 #ifdef CONFIG_DYNAMIC_FTRACE
979 extern struct ftrace_hash __rcu *ftrace_graph_hash;
980 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
981 
982 static inline int
983 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
984 {
985 	unsigned long addr = trace->func;
986 	int ret = 0;
987 	struct ftrace_hash *hash;
988 
989 	preempt_disable_notrace();
990 
991 	/*
992 	 * Have to open code "rcu_dereference_sched()" because the
993 	 * function graph tracer can be called when RCU is not
994 	 * "watching".
995 	 * Protected with schedule_on_each_cpu(ftrace_sync)
996 	 */
997 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
998 
999 	if (ftrace_hash_empty(hash)) {
1000 		ret = 1;
1001 		goto out;
1002 	}
1003 
1004 	if (ftrace_lookup_ip(hash, addr)) {
1005 		/*
1006 		 * This needs to be cleared on the return functions
1007 		 * when the depth is zero.
1008 		 */
1009 		*task_var |= TRACE_GRAPH_FL;
1010 		ftrace_graph_set_depth(task_var, trace->depth);
1011 
1012 		/*
1013 		 * If no irqs are to be traced, but a set_graph_function
1014 		 * is set, and called by an interrupt handler, we still
1015 		 * want to trace it.
1016 		 */
1017 		if (in_hardirq())
1018 			trace_recursion_set(TRACE_IRQ_BIT);
1019 		else
1020 			trace_recursion_clear(TRACE_IRQ_BIT);
1021 		ret = 1;
1022 	}
1023 
1024 out:
1025 	preempt_enable_notrace();
1026 	return ret;
1027 }
1028 
1029 static inline void
1030 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1031 {
1032 	unsigned long *task_var = fgraph_get_task_var(gops);
1033 
1034 	if ((*task_var & TRACE_GRAPH_FL) &&
1035 	    trace->depth == ftrace_graph_depth(task_var))
1036 		*task_var &= ~TRACE_GRAPH_FL;
1037 }
1038 
1039 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1040 {
1041 	int ret = 0;
1042 	struct ftrace_hash *notrace_hash;
1043 
1044 	preempt_disable_notrace();
1045 
1046 	/*
1047 	 * Have to open code "rcu_dereference_sched()" because the
1048 	 * function graph tracer can be called when RCU is not
1049 	 * "watching".
1050 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1051 	 */
1052 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1053 						 !preemptible());
1054 
1055 	if (ftrace_lookup_ip(notrace_hash, addr))
1056 		ret = 1;
1057 
1058 	preempt_enable_notrace();
1059 	return ret;
1060 }
1061 #else
1062 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1063 {
1064 	return 1;
1065 }
1066 
1067 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1068 {
1069 	return 0;
1070 }
1071 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1072 { }
1073 #endif /* CONFIG_DYNAMIC_FTRACE */
1074 
1075 extern unsigned int fgraph_max_depth;
1076 extern bool fgraph_sleep_time;
1077 
1078 static inline bool
1079 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1080 {
1081 	unsigned long *task_var = fgraph_get_task_var(gops);
1082 
1083 	/* trace it when it is-nested-in or is a function enabled. */
1084 	return !((*task_var & TRACE_GRAPH_FL) ||
1085 		 ftrace_graph_addr(task_var, trace)) ||
1086 		(trace->depth < 0) ||
1087 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1088 }
1089 
1090 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1091 		     struct ftrace_ops *src_ops);
1092 
1093 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1094 static inline enum print_line_t
1095 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1096 {
1097 	return TRACE_TYPE_UNHANDLED;
1098 }
1099 static inline void free_fgraph_ops(struct trace_array *tr) { }
1100 /* ftrace_ops may not be defined */
1101 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1102 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1103 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1104 
1105 extern struct list_head ftrace_pids;
1106 
1107 #ifdef CONFIG_FUNCTION_TRACER
1108 
1109 #define FTRACE_PID_IGNORE	-1
1110 #define FTRACE_PID_TRACE	-2
1111 
1112 struct ftrace_func_command {
1113 	struct list_head	list;
1114 	char			*name;
1115 	int			(*func)(struct trace_array *tr,
1116 					struct ftrace_hash *hash,
1117 					char *func, char *cmd,
1118 					char *params, int enable);
1119 };
1120 extern bool ftrace_filter_param __initdata;
1121 static inline int ftrace_trace_task(struct trace_array *tr)
1122 {
1123 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1124 		FTRACE_PID_IGNORE;
1125 }
1126 extern int ftrace_is_dead(void);
1127 int ftrace_create_function_files(struct trace_array *tr,
1128 				 struct dentry *parent);
1129 void ftrace_destroy_function_files(struct trace_array *tr);
1130 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1131 void ftrace_free_ftrace_ops(struct trace_array *tr);
1132 void ftrace_init_global_array_ops(struct trace_array *tr);
1133 struct trace_array *trace_get_global_array(void);
1134 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1135 void ftrace_reset_array_ops(struct trace_array *tr);
1136 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1137 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1138 				  struct dentry *d_tracer);
1139 void ftrace_clear_pids(struct trace_array *tr);
1140 int init_function_trace(void);
1141 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1142 #else
1143 static inline int ftrace_trace_task(struct trace_array *tr)
1144 {
1145 	return 1;
1146 }
1147 static inline int ftrace_is_dead(void) { return 0; }
1148 static inline int
1149 ftrace_create_function_files(struct trace_array *tr,
1150 			     struct dentry *parent)
1151 {
1152 	return 0;
1153 }
1154 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1155 {
1156 	return 0;
1157 }
1158 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1159 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1160 static inline __init void
1161 ftrace_init_global_array_ops(struct trace_array *tr) { }
1162 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1163 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1164 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1165 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1166 static inline int init_function_trace(void) { return 0; }
1167 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1168 /* ftace_func_t type is not defined, use macro instead of static inline */
1169 #define ftrace_init_array_ops(tr, func) do { } while (0)
1170 #endif /* CONFIG_FUNCTION_TRACER */
1171 
1172 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1173 
1174 struct ftrace_probe_ops {
1175 	void			(*func)(unsigned long ip,
1176 					unsigned long parent_ip,
1177 					struct trace_array *tr,
1178 					struct ftrace_probe_ops *ops,
1179 					void *data);
1180 	int			(*init)(struct ftrace_probe_ops *ops,
1181 					struct trace_array *tr,
1182 					unsigned long ip, void *init_data,
1183 					void **data);
1184 	void			(*free)(struct ftrace_probe_ops *ops,
1185 					struct trace_array *tr,
1186 					unsigned long ip, void *data);
1187 	int			(*print)(struct seq_file *m,
1188 					 unsigned long ip,
1189 					 struct ftrace_probe_ops *ops,
1190 					 void *data);
1191 };
1192 
1193 struct ftrace_func_mapper;
1194 typedef int (*ftrace_mapper_func)(void *data);
1195 
1196 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1197 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1198 					   unsigned long ip);
1199 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1200 			       unsigned long ip, void *data);
1201 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1202 				   unsigned long ip);
1203 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1204 			     ftrace_mapper_func free_func);
1205 
1206 extern int
1207 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1208 			       struct ftrace_probe_ops *ops, void *data);
1209 extern int
1210 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1211 				      struct ftrace_probe_ops *ops);
1212 extern void clear_ftrace_function_probes(struct trace_array *tr);
1213 
1214 int register_ftrace_command(struct ftrace_func_command *cmd);
1215 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1216 
1217 void ftrace_create_filter_files(struct ftrace_ops *ops,
1218 				struct dentry *parent);
1219 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1220 
1221 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1222 			     int len, int reset);
1223 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1224 			      int len, int reset);
1225 #else
1226 struct ftrace_func_command;
1227 
1228 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1229 {
1230 	return -EINVAL;
1231 }
1232 static inline __init int unregister_ftrace_command(char *cmd_name)
1233 {
1234 	return -EINVAL;
1235 }
1236 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1237 {
1238 }
1239 
1240 /*
1241  * The ops parameter passed in is usually undefined.
1242  * This must be a macro.
1243  */
1244 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1245 #define ftrace_destroy_filter_files(ops) do { } while (0)
1246 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1247 
1248 bool ftrace_event_is_function(struct trace_event_call *call);
1249 
1250 /*
1251  * struct trace_parser - servers for reading the user input separated by spaces
1252  * @cont: set if the input is not complete - no final space char was found
1253  * @buffer: holds the parsed user input
1254  * @idx: user input length
1255  * @size: buffer size
1256  */
1257 struct trace_parser {
1258 	bool		cont;
1259 	char		*buffer;
1260 	unsigned	idx;
1261 	unsigned	size;
1262 };
1263 
1264 static inline bool trace_parser_loaded(struct trace_parser *parser)
1265 {
1266 	return (parser->idx != 0);
1267 }
1268 
1269 static inline bool trace_parser_cont(struct trace_parser *parser)
1270 {
1271 	return parser->cont;
1272 }
1273 
1274 static inline void trace_parser_clear(struct trace_parser *parser)
1275 {
1276 	parser->cont = false;
1277 	parser->idx = 0;
1278 }
1279 
1280 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1281 extern void trace_parser_put(struct trace_parser *parser);
1282 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1283 	size_t cnt, loff_t *ppos);
1284 
1285 /*
1286  * Only create function graph options if function graph is configured.
1287  */
1288 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1289 # define FGRAPH_FLAGS						\
1290 		C(DISPLAY_GRAPH,	"display-graph"),
1291 #else
1292 # define FGRAPH_FLAGS
1293 #endif
1294 
1295 #ifdef CONFIG_BRANCH_TRACER
1296 # define BRANCH_FLAGS					\
1297 		C(BRANCH,		"branch"),
1298 #else
1299 # define BRANCH_FLAGS
1300 #endif
1301 
1302 #ifdef CONFIG_FUNCTION_TRACER
1303 # define FUNCTION_FLAGS						\
1304 		C(FUNCTION,		"function-trace"),	\
1305 		C(FUNC_FORK,		"function-fork"),
1306 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1307 #else
1308 # define FUNCTION_FLAGS
1309 # define FUNCTION_DEFAULT_FLAGS		0UL
1310 # define TRACE_ITER_FUNC_FORK		0UL
1311 #endif
1312 
1313 #ifdef CONFIG_STACKTRACE
1314 # define STACK_FLAGS				\
1315 		C(STACKTRACE,		"stacktrace"),
1316 #else
1317 # define STACK_FLAGS
1318 #endif
1319 
1320 /*
1321  * trace_iterator_flags is an enumeration that defines bit
1322  * positions into trace_flags that controls the output.
1323  *
1324  * NOTE: These bits must match the trace_options array in
1325  *       trace.c (this macro guarantees it).
1326  */
1327 #define TRACE_FLAGS						\
1328 		C(PRINT_PARENT,		"print-parent"),	\
1329 		C(SYM_OFFSET,		"sym-offset"),		\
1330 		C(SYM_ADDR,		"sym-addr"),		\
1331 		C(VERBOSE,		"verbose"),		\
1332 		C(RAW,			"raw"),			\
1333 		C(HEX,			"hex"),			\
1334 		C(BIN,			"bin"),			\
1335 		C(BLOCK,		"block"),		\
1336 		C(FIELDS,		"fields"),		\
1337 		C(PRINTK,		"trace_printk"),	\
1338 		C(ANNOTATE,		"annotate"),		\
1339 		C(USERSTACKTRACE,	"userstacktrace"),	\
1340 		C(SYM_USEROBJ,		"sym-userobj"),		\
1341 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1342 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1343 		C(LATENCY_FMT,		"latency-format"),	\
1344 		C(RECORD_CMD,		"record-cmd"),		\
1345 		C(RECORD_TGID,		"record-tgid"),		\
1346 		C(OVERWRITE,		"overwrite"),		\
1347 		C(STOP_ON_FREE,		"disable_on_free"),	\
1348 		C(IRQ_INFO,		"irq-info"),		\
1349 		C(MARKERS,		"markers"),		\
1350 		C(EVENT_FORK,		"event-fork"),		\
1351 		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1352 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1353 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1354 		FUNCTION_FLAGS					\
1355 		FGRAPH_FLAGS					\
1356 		STACK_FLAGS					\
1357 		BRANCH_FLAGS
1358 
1359 /*
1360  * By defining C, we can make TRACE_FLAGS a list of bit names
1361  * that will define the bits for the flag masks.
1362  */
1363 #undef C
1364 #define C(a, b) TRACE_ITER_##a##_BIT
1365 
1366 enum trace_iterator_bits {
1367 	TRACE_FLAGS
1368 	/* Make sure we don't go more than we have bits for */
1369 	TRACE_ITER_LAST_BIT
1370 };
1371 
1372 /*
1373  * By redefining C, we can make TRACE_FLAGS a list of masks that
1374  * use the bits as defined above.
1375  */
1376 #undef C
1377 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1378 
1379 enum trace_iterator_flags { TRACE_FLAGS };
1380 
1381 /*
1382  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1383  * control the output of kernel symbols.
1384  */
1385 #define TRACE_ITER_SYM_MASK \
1386 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1387 
1388 extern struct tracer nop_trace;
1389 
1390 #ifdef CONFIG_BRANCH_TRACER
1391 extern int enable_branch_tracing(struct trace_array *tr);
1392 extern void disable_branch_tracing(void);
1393 static inline int trace_branch_enable(struct trace_array *tr)
1394 {
1395 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1396 		return enable_branch_tracing(tr);
1397 	return 0;
1398 }
1399 static inline void trace_branch_disable(void)
1400 {
1401 	/* due to races, always disable */
1402 	disable_branch_tracing();
1403 }
1404 #else
1405 static inline int trace_branch_enable(struct trace_array *tr)
1406 {
1407 	return 0;
1408 }
1409 static inline void trace_branch_disable(void)
1410 {
1411 }
1412 #endif /* CONFIG_BRANCH_TRACER */
1413 
1414 /* set ring buffers to default size if not already done so */
1415 int tracing_update_buffers(struct trace_array *tr);
1416 
1417 union trace_synth_field {
1418 	u8				as_u8;
1419 	u16				as_u16;
1420 	u32				as_u32;
1421 	u64				as_u64;
1422 	struct trace_dynamic_info	as_dynamic;
1423 };
1424 
1425 struct ftrace_event_field {
1426 	struct list_head	link;
1427 	const char		*name;
1428 	const char		*type;
1429 	int			filter_type;
1430 	int			offset;
1431 	int			size;
1432 	unsigned int		is_signed:1;
1433 	unsigned int		needs_test:1;
1434 	int			len;
1435 };
1436 
1437 struct prog_entry;
1438 
1439 struct event_filter {
1440 	struct prog_entry __rcu	*prog;
1441 	char			*filter_string;
1442 };
1443 
1444 struct event_subsystem {
1445 	struct list_head	list;
1446 	const char		*name;
1447 	struct event_filter	*filter;
1448 	int			ref_count;
1449 };
1450 
1451 struct trace_subsystem_dir {
1452 	struct list_head		list;
1453 	struct event_subsystem		*subsystem;
1454 	struct trace_array		*tr;
1455 	struct eventfs_inode		*ei;
1456 	int				ref_count;
1457 	int				nr_events;
1458 };
1459 
1460 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1461 				     struct trace_buffer *buffer,
1462 				     struct ring_buffer_event *event,
1463 				     unsigned int trcace_ctx,
1464 				     struct pt_regs *regs);
1465 
1466 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1467 					      struct trace_buffer *buffer,
1468 					      struct ring_buffer_event *event,
1469 					      unsigned int trace_ctx)
1470 {
1471 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1472 }
1473 
1474 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1475 int trace_save_cmdline(struct task_struct *tsk);
1476 int trace_create_savedcmd(void);
1477 int trace_alloc_tgid_map(void);
1478 void trace_free_saved_cmdlines_buffer(void);
1479 
1480 extern const struct file_operations tracing_saved_cmdlines_fops;
1481 extern const struct file_operations tracing_saved_tgids_fops;
1482 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1483 
1484 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1485 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1486 void trace_buffered_event_disable(void);
1487 void trace_buffered_event_enable(void);
1488 
1489 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1490 
1491 static inline void
1492 __trace_event_discard_commit(struct trace_buffer *buffer,
1493 			     struct ring_buffer_event *event)
1494 {
1495 	if (this_cpu_read(trace_buffered_event) == event) {
1496 		/* Simply release the temp buffer and enable preemption */
1497 		this_cpu_dec(trace_buffered_event_cnt);
1498 		preempt_enable_notrace();
1499 		return;
1500 	}
1501 	/* ring_buffer_discard_commit() enables preemption */
1502 	ring_buffer_discard_commit(buffer, event);
1503 }
1504 
1505 /*
1506  * Helper function for event_trigger_unlock_commit{_regs}().
1507  * If there are event triggers attached to this event that requires
1508  * filtering against its fields, then they will be called as the
1509  * entry already holds the field information of the current event.
1510  *
1511  * It also checks if the event should be discarded or not.
1512  * It is to be discarded if the event is soft disabled and the
1513  * event was only recorded to process triggers, or if the event
1514  * filter is active and this event did not match the filters.
1515  *
1516  * Returns true if the event is discarded, false otherwise.
1517  */
1518 static inline bool
1519 __event_trigger_test_discard(struct trace_event_file *file,
1520 			     struct trace_buffer *buffer,
1521 			     struct ring_buffer_event *event,
1522 			     void *entry,
1523 			     enum event_trigger_type *tt)
1524 {
1525 	unsigned long eflags = file->flags;
1526 
1527 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1528 		*tt = event_triggers_call(file, buffer, entry, event);
1529 
1530 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1531 				    EVENT_FILE_FL_FILTERED |
1532 				    EVENT_FILE_FL_PID_FILTER))))
1533 		return false;
1534 
1535 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1536 		goto discard;
1537 
1538 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1539 	    !filter_match_preds(file->filter, entry))
1540 		goto discard;
1541 
1542 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1543 	    trace_event_ignore_this_pid(file))
1544 		goto discard;
1545 
1546 	return false;
1547  discard:
1548 	__trace_event_discard_commit(buffer, event);
1549 	return true;
1550 }
1551 
1552 /**
1553  * event_trigger_unlock_commit - handle triggers and finish event commit
1554  * @file: The file pointer associated with the event
1555  * @buffer: The ring buffer that the event is being written to
1556  * @event: The event meta data in the ring buffer
1557  * @entry: The event itself
1558  * @trace_ctx: The tracing context flags.
1559  *
1560  * This is a helper function to handle triggers that require data
1561  * from the event itself. It also tests the event against filters and
1562  * if the event is soft disabled and should be discarded.
1563  */
1564 static inline void
1565 event_trigger_unlock_commit(struct trace_event_file *file,
1566 			    struct trace_buffer *buffer,
1567 			    struct ring_buffer_event *event,
1568 			    void *entry, unsigned int trace_ctx)
1569 {
1570 	enum event_trigger_type tt = ETT_NONE;
1571 
1572 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1573 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1574 
1575 	if (tt)
1576 		event_triggers_post_call(file, tt);
1577 }
1578 
1579 #define FILTER_PRED_INVALID	((unsigned short)-1)
1580 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1581 #define FILTER_PRED_FOLD	(1 << 15)
1582 
1583 /*
1584  * The max preds is the size of unsigned short with
1585  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1586  * and FOLD flags. The other is reserved.
1587  *
1588  * 2^14 preds is way more than enough.
1589  */
1590 #define MAX_FILTER_PRED		16384
1591 
1592 struct filter_pred;
1593 struct regex;
1594 
1595 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1596 
1597 enum regex_type {
1598 	MATCH_FULL = 0,
1599 	MATCH_FRONT_ONLY,
1600 	MATCH_MIDDLE_ONLY,
1601 	MATCH_END_ONLY,
1602 	MATCH_GLOB,
1603 	MATCH_INDEX,
1604 };
1605 
1606 struct regex {
1607 	char			pattern[MAX_FILTER_STR_VAL];
1608 	int			len;
1609 	int			field_len;
1610 	regex_match_func	match;
1611 };
1612 
1613 static inline bool is_string_field(struct ftrace_event_field *field)
1614 {
1615 	return field->filter_type == FILTER_DYN_STRING ||
1616 	       field->filter_type == FILTER_RDYN_STRING ||
1617 	       field->filter_type == FILTER_STATIC_STRING ||
1618 	       field->filter_type == FILTER_PTR_STRING ||
1619 	       field->filter_type == FILTER_COMM;
1620 }
1621 
1622 static inline bool is_function_field(struct ftrace_event_field *field)
1623 {
1624 	return field->filter_type == FILTER_TRACE_FN;
1625 }
1626 
1627 extern enum regex_type
1628 filter_parse_regex(char *buff, int len, char **search, int *not);
1629 extern void print_event_filter(struct trace_event_file *file,
1630 			       struct trace_seq *s);
1631 extern int apply_event_filter(struct trace_event_file *file,
1632 			      char *filter_string);
1633 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1634 					char *filter_string);
1635 extern void print_subsystem_event_filter(struct event_subsystem *system,
1636 					 struct trace_seq *s);
1637 extern int filter_assign_type(const char *type);
1638 extern int create_event_filter(struct trace_array *tr,
1639 			       struct trace_event_call *call,
1640 			       char *filter_str, bool set_str,
1641 			       struct event_filter **filterp);
1642 extern void free_event_filter(struct event_filter *filter);
1643 
1644 struct ftrace_event_field *
1645 trace_find_event_field(struct trace_event_call *call, char *name);
1646 
1647 extern void trace_event_enable_cmd_record(bool enable);
1648 extern void trace_event_enable_tgid_record(bool enable);
1649 
1650 extern int event_trace_init(void);
1651 extern int init_events(void);
1652 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1653 extern int event_trace_del_tracer(struct trace_array *tr);
1654 extern void __trace_early_add_events(struct trace_array *tr);
1655 
1656 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1657 						  const char *system,
1658 						  const char *event);
1659 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1660 						const char *system,
1661 						const char *event);
1662 
1663 static inline void *event_file_data(struct file *filp)
1664 {
1665 	return READ_ONCE(file_inode(filp)->i_private);
1666 }
1667 
1668 extern struct mutex event_mutex;
1669 extern struct list_head ftrace_events;
1670 
1671 /*
1672  * When the trace_event_file is the filp->i_private pointer,
1673  * it must be taken under the event_mutex lock, and then checked
1674  * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1675  * data pointed to by the trace_event_file can not be trusted.
1676  *
1677  * Use the event_file_file() to access the trace_event_file from
1678  * the filp the first time under the event_mutex and check for
1679  * NULL. If it is needed to be retrieved again and the event_mutex
1680  * is still held, then the event_file_data() can be used and it
1681  * is guaranteed to be valid.
1682  */
1683 static inline struct trace_event_file *event_file_file(struct file *filp)
1684 {
1685 	struct trace_event_file *file;
1686 
1687 	lockdep_assert_held(&event_mutex);
1688 	file = READ_ONCE(file_inode(filp)->i_private);
1689 	if (!file || file->flags & EVENT_FILE_FL_FREED)
1690 		return NULL;
1691 	return file;
1692 }
1693 
1694 extern const struct file_operations event_trigger_fops;
1695 extern const struct file_operations event_hist_fops;
1696 extern const struct file_operations event_hist_debug_fops;
1697 extern const struct file_operations event_inject_fops;
1698 
1699 #ifdef CONFIG_HIST_TRIGGERS
1700 extern int register_trigger_hist_cmd(void);
1701 extern int register_trigger_hist_enable_disable_cmds(void);
1702 #else
1703 static inline int register_trigger_hist_cmd(void) { return 0; }
1704 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1705 #endif
1706 
1707 extern int register_trigger_cmds(void);
1708 extern void clear_event_triggers(struct trace_array *tr);
1709 
1710 enum {
1711 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1712 };
1713 
1714 struct event_trigger_data {
1715 	unsigned long			count;
1716 	int				ref;
1717 	int				flags;
1718 	struct event_trigger_ops	*ops;
1719 	struct event_command		*cmd_ops;
1720 	struct event_filter __rcu	*filter;
1721 	char				*filter_str;
1722 	void				*private_data;
1723 	bool				paused;
1724 	bool				paused_tmp;
1725 	struct list_head		list;
1726 	char				*name;
1727 	struct list_head		named_list;
1728 	struct event_trigger_data	*named_data;
1729 };
1730 
1731 /* Avoid typos */
1732 #define ENABLE_EVENT_STR	"enable_event"
1733 #define DISABLE_EVENT_STR	"disable_event"
1734 #define ENABLE_HIST_STR		"enable_hist"
1735 #define DISABLE_HIST_STR	"disable_hist"
1736 
1737 struct enable_trigger_data {
1738 	struct trace_event_file		*file;
1739 	bool				enable;
1740 	bool				hist;
1741 };
1742 
1743 extern int event_enable_trigger_print(struct seq_file *m,
1744 				      struct event_trigger_data *data);
1745 extern void event_enable_trigger_free(struct event_trigger_data *data);
1746 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1747 				      struct trace_event_file *file,
1748 				      char *glob, char *cmd,
1749 				      char *param_and_filter);
1750 extern int event_enable_register_trigger(char *glob,
1751 					 struct event_trigger_data *data,
1752 					 struct trace_event_file *file);
1753 extern void event_enable_unregister_trigger(char *glob,
1754 					    struct event_trigger_data *test,
1755 					    struct trace_event_file *file);
1756 extern void trigger_data_free(struct event_trigger_data *data);
1757 extern int event_trigger_init(struct event_trigger_data *data);
1758 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1759 					      int trigger_enable);
1760 extern void update_cond_flag(struct trace_event_file *file);
1761 extern int set_trigger_filter(char *filter_str,
1762 			      struct event_trigger_data *trigger_data,
1763 			      struct trace_event_file *file);
1764 extern struct event_trigger_data *find_named_trigger(const char *name);
1765 extern bool is_named_trigger(struct event_trigger_data *test);
1766 extern int save_named_trigger(const char *name,
1767 			      struct event_trigger_data *data);
1768 extern void del_named_trigger(struct event_trigger_data *data);
1769 extern void pause_named_trigger(struct event_trigger_data *data);
1770 extern void unpause_named_trigger(struct event_trigger_data *data);
1771 extern void set_named_trigger_data(struct event_trigger_data *data,
1772 				   struct event_trigger_data *named_data);
1773 extern struct event_trigger_data *
1774 get_named_trigger_data(struct event_trigger_data *data);
1775 extern int register_event_command(struct event_command *cmd);
1776 extern int unregister_event_command(struct event_command *cmd);
1777 extern int register_trigger_hist_enable_disable_cmds(void);
1778 extern bool event_trigger_check_remove(const char *glob);
1779 extern bool event_trigger_empty_param(const char *param);
1780 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1781 					 char **filter, bool param_required);
1782 extern struct event_trigger_data *
1783 event_trigger_alloc(struct event_command *cmd_ops,
1784 		    char *cmd,
1785 		    char *param,
1786 		    void *private_data);
1787 extern int event_trigger_parse_num(char *trigger,
1788 				   struct event_trigger_data *trigger_data);
1789 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1790 				    struct trace_event_file *file,
1791 				    char *param,
1792 				    struct event_trigger_data *trigger_data);
1793 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1794 				       struct event_trigger_data *trigger_data);
1795 extern int event_trigger_register(struct event_command *cmd_ops,
1796 				  struct trace_event_file *file,
1797 				  char *glob,
1798 				  struct event_trigger_data *trigger_data);
1799 extern void event_trigger_unregister(struct event_command *cmd_ops,
1800 				     struct trace_event_file *file,
1801 				     char *glob,
1802 				     struct event_trigger_data *trigger_data);
1803 
1804 extern void event_file_get(struct trace_event_file *file);
1805 extern void event_file_put(struct trace_event_file *file);
1806 
1807 /**
1808  * struct event_trigger_ops - callbacks for trace event triggers
1809  *
1810  * The methods in this structure provide per-event trigger hooks for
1811  * various trigger operations.
1812  *
1813  * The @init and @free methods are used during trigger setup and
1814  * teardown, typically called from an event_command's @parse()
1815  * function implementation.
1816  *
1817  * The @print method is used to print the trigger spec.
1818  *
1819  * The @trigger method is the function that actually implements the
1820  * trigger and is called in the context of the triggering event
1821  * whenever that event occurs.
1822  *
1823  * All the methods below, except for @init() and @free(), must be
1824  * implemented.
1825  *
1826  * @trigger: The trigger 'probe' function called when the triggering
1827  *	event occurs.  The data passed into this callback is the data
1828  *	that was supplied to the event_command @reg() function that
1829  *	registered the trigger (see struct event_command) along with
1830  *	the trace record, rec.
1831  *
1832  * @init: An optional initialization function called for the trigger
1833  *	when the trigger is registered (via the event_command reg()
1834  *	function).  This can be used to perform per-trigger
1835  *	initialization such as incrementing a per-trigger reference
1836  *	count, for instance.  This is usually implemented by the
1837  *	generic utility function @event_trigger_init() (see
1838  *	trace_event_triggers.c).
1839  *
1840  * @free: An optional de-initialization function called for the
1841  *	trigger when the trigger is unregistered (via the
1842  *	event_command @reg() function).  This can be used to perform
1843  *	per-trigger de-initialization such as decrementing a
1844  *	per-trigger reference count and freeing corresponding trigger
1845  *	data, for instance.  This is usually implemented by the
1846  *	generic utility function @event_trigger_free() (see
1847  *	trace_event_triggers.c).
1848  *
1849  * @print: The callback function invoked to have the trigger print
1850  *	itself.  This is usually implemented by a wrapper function
1851  *	that calls the generic utility function @event_trigger_print()
1852  *	(see trace_event_triggers.c).
1853  */
1854 struct event_trigger_ops {
1855 	void			(*trigger)(struct event_trigger_data *data,
1856 					   struct trace_buffer *buffer,
1857 					   void *rec,
1858 					   struct ring_buffer_event *rbe);
1859 	int			(*init)(struct event_trigger_data *data);
1860 	void			(*free)(struct event_trigger_data *data);
1861 	int			(*print)(struct seq_file *m,
1862 					 struct event_trigger_data *data);
1863 };
1864 
1865 /**
1866  * struct event_command - callbacks and data members for event commands
1867  *
1868  * Event commands are invoked by users by writing the command name
1869  * into the 'trigger' file associated with a trace event.  The
1870  * parameters associated with a specific invocation of an event
1871  * command are used to create an event trigger instance, which is
1872  * added to the list of trigger instances associated with that trace
1873  * event.  When the event is hit, the set of triggers associated with
1874  * that event is invoked.
1875  *
1876  * The data members in this structure provide per-event command data
1877  * for various event commands.
1878  *
1879  * All the data members below, except for @post_trigger, must be set
1880  * for each event command.
1881  *
1882  * @name: The unique name that identifies the event command.  This is
1883  *	the name used when setting triggers via trigger files.
1884  *
1885  * @trigger_type: A unique id that identifies the event command
1886  *	'type'.  This value has two purposes, the first to ensure that
1887  *	only one trigger of the same type can be set at a given time
1888  *	for a particular event e.g. it doesn't make sense to have both
1889  *	a traceon and traceoff trigger attached to a single event at
1890  *	the same time, so traceon and traceoff have the same type
1891  *	though they have different names.  The @trigger_type value is
1892  *	also used as a bit value for deferring the actual trigger
1893  *	action until after the current event is finished.  Some
1894  *	commands need to do this if they themselves log to the trace
1895  *	buffer (see the @post_trigger() member below).  @trigger_type
1896  *	values are defined by adding new values to the trigger_type
1897  *	enum in include/linux/trace_events.h.
1898  *
1899  * @flags: See the enum event_command_flags below.
1900  *
1901  * All the methods below, except for @set_filter() and @unreg_all(),
1902  * must be implemented.
1903  *
1904  * @parse: The callback function responsible for parsing and
1905  *	registering the trigger written to the 'trigger' file by the
1906  *	user.  It allocates the trigger instance and registers it with
1907  *	the appropriate trace event.  It makes use of the other
1908  *	event_command callback functions to orchestrate this, and is
1909  *	usually implemented by the generic utility function
1910  *	@event_trigger_callback() (see trace_event_triggers.c).
1911  *
1912  * @reg: Adds the trigger to the list of triggers associated with the
1913  *	event, and enables the event trigger itself, after
1914  *	initializing it (via the event_trigger_ops @init() function).
1915  *	This is also where commands can use the @trigger_type value to
1916  *	make the decision as to whether or not multiple instances of
1917  *	the trigger should be allowed.  This is usually implemented by
1918  *	the generic utility function @register_trigger() (see
1919  *	trace_event_triggers.c).
1920  *
1921  * @unreg: Removes the trigger from the list of triggers associated
1922  *	with the event, and disables the event trigger itself, after
1923  *	initializing it (via the event_trigger_ops @free() function).
1924  *	This is usually implemented by the generic utility function
1925  *	@unregister_trigger() (see trace_event_triggers.c).
1926  *
1927  * @unreg_all: An optional function called to remove all the triggers
1928  *	from the list of triggers associated with the event.  Called
1929  *	when a trigger file is opened in truncate mode.
1930  *
1931  * @set_filter: An optional function called to parse and set a filter
1932  *	for the trigger.  If no @set_filter() method is set for the
1933  *	event command, filters set by the user for the command will be
1934  *	ignored.  This is usually implemented by the generic utility
1935  *	function @set_trigger_filter() (see trace_event_triggers.c).
1936  *
1937  * @get_trigger_ops: The callback function invoked to retrieve the
1938  *	event_trigger_ops implementation associated with the command.
1939  *	This callback function allows a single event_command to
1940  *	support multiple trigger implementations via different sets of
1941  *	event_trigger_ops, depending on the value of the @param
1942  *	string.
1943  */
1944 struct event_command {
1945 	struct list_head	list;
1946 	char			*name;
1947 	enum event_trigger_type	trigger_type;
1948 	int			flags;
1949 	int			(*parse)(struct event_command *cmd_ops,
1950 					 struct trace_event_file *file,
1951 					 char *glob, char *cmd,
1952 					 char *param_and_filter);
1953 	int			(*reg)(char *glob,
1954 				       struct event_trigger_data *data,
1955 				       struct trace_event_file *file);
1956 	void			(*unreg)(char *glob,
1957 					 struct event_trigger_data *data,
1958 					 struct trace_event_file *file);
1959 	void			(*unreg_all)(struct trace_event_file *file);
1960 	int			(*set_filter)(char *filter_str,
1961 					      struct event_trigger_data *data,
1962 					      struct trace_event_file *file);
1963 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1964 };
1965 
1966 /**
1967  * enum event_command_flags - flags for struct event_command
1968  *
1969  * @POST_TRIGGER: A flag that says whether or not this command needs
1970  *	to have its action delayed until after the current event has
1971  *	been closed.  Some triggers need to avoid being invoked while
1972  *	an event is currently in the process of being logged, since
1973  *	the trigger may itself log data into the trace buffer.  Thus
1974  *	we make sure the current event is committed before invoking
1975  *	those triggers.  To do that, the trigger invocation is split
1976  *	in two - the first part checks the filter using the current
1977  *	trace record; if a command has the @post_trigger flag set, it
1978  *	sets a bit for itself in the return value, otherwise it
1979  *	directly invokes the trigger.  Once all commands have been
1980  *	either invoked or set their return flag, the current record is
1981  *	either committed or discarded.  At that point, if any commands
1982  *	have deferred their triggers, those commands are finally
1983  *	invoked following the close of the current event.  In other
1984  *	words, if the event_trigger_ops @func() probe implementation
1985  *	itself logs to the trace buffer, this flag should be set,
1986  *	otherwise it can be left unspecified.
1987  *
1988  * @NEEDS_REC: A flag that says whether or not this command needs
1989  *	access to the trace record in order to perform its function,
1990  *	regardless of whether or not it has a filter associated with
1991  *	it (filters make a trigger require access to the trace record
1992  *	but are not always present).
1993  */
1994 enum event_command_flags {
1995 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1996 	EVENT_CMD_FL_NEEDS_REC		= 2,
1997 };
1998 
1999 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
2000 {
2001 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
2002 }
2003 
2004 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
2005 {
2006 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
2007 }
2008 
2009 extern int trace_event_enable_disable(struct trace_event_file *file,
2010 				      int enable, int soft_disable);
2011 extern int tracing_alloc_snapshot(void);
2012 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
2013 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
2014 
2015 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
2016 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2017 
2018 extern const char *__start___trace_bprintk_fmt[];
2019 extern const char *__stop___trace_bprintk_fmt[];
2020 
2021 extern const char *__start___tracepoint_str[];
2022 extern const char *__stop___tracepoint_str[];
2023 
2024 void trace_printk_control(bool enabled);
2025 void trace_printk_start_comm(void);
2026 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2027 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2028 
2029 /* Used from boot time tracer */
2030 extern int trace_set_options(struct trace_array *tr, char *option);
2031 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2032 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2033 					  unsigned long size, int cpu_id);
2034 extern int tracing_set_cpumask(struct trace_array *tr,
2035 				cpumask_var_t tracing_cpumask_new);
2036 
2037 
2038 #define MAX_EVENT_NAME_LEN	64
2039 
2040 extern ssize_t trace_parse_run_command(struct file *file,
2041 		const char __user *buffer, size_t count, loff_t *ppos,
2042 		int (*createfn)(const char *));
2043 
2044 extern unsigned int err_pos(char *cmd, const char *str);
2045 extern void tracing_log_err(struct trace_array *tr,
2046 			    const char *loc, const char *cmd,
2047 			    const char **errs, u8 type, u16 pos);
2048 
2049 /*
2050  * Normal trace_printk() and friends allocates special buffers
2051  * to do the manipulation, as well as saves the print formats
2052  * into sections to display. But the trace infrastructure wants
2053  * to use these without the added overhead at the price of being
2054  * a bit slower (used mainly for warnings, where we don't care
2055  * about performance). The internal_trace_puts() is for such
2056  * a purpose.
2057  */
2058 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2059 
2060 #undef FTRACE_ENTRY
2061 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2062 	extern struct trace_event_call					\
2063 	__aligned(4) event_##call;
2064 #undef FTRACE_ENTRY_DUP
2065 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2066 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2067 #undef FTRACE_ENTRY_PACKED
2068 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2069 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2070 
2071 #include "trace_entries.h"
2072 
2073 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2074 int perf_ftrace_event_register(struct trace_event_call *call,
2075 			       enum trace_reg type, void *data);
2076 #else
2077 #define perf_ftrace_event_register NULL
2078 #endif
2079 
2080 #ifdef CONFIG_FTRACE_SYSCALLS
2081 void init_ftrace_syscalls(void);
2082 const char *get_syscall_name(int syscall);
2083 #else
2084 static inline void init_ftrace_syscalls(void) { }
2085 static inline const char *get_syscall_name(int syscall)
2086 {
2087 	return NULL;
2088 }
2089 #endif
2090 
2091 #ifdef CONFIG_EVENT_TRACING
2092 void trace_event_init(void);
2093 void trace_event_eval_update(struct trace_eval_map **map, int len);
2094 /* Used from boot time tracer */
2095 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2096 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2097 #else
2098 static inline void __init trace_event_init(void) { }
2099 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2100 #endif
2101 
2102 #ifdef CONFIG_TRACER_SNAPSHOT
2103 void tracing_snapshot_instance(struct trace_array *tr);
2104 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2105 int tracing_arm_snapshot(struct trace_array *tr);
2106 void tracing_disarm_snapshot(struct trace_array *tr);
2107 #else
2108 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2109 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2110 {
2111 	return 0;
2112 }
2113 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
2114 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2115 #endif
2116 
2117 #ifdef CONFIG_PREEMPT_TRACER
2118 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2119 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2120 #else
2121 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2122 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2123 #endif
2124 #ifdef CONFIG_IRQSOFF_TRACER
2125 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2126 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2127 #else
2128 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2129 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2130 #endif
2131 
2132 /*
2133  * Reset the state of the trace_iterator so that it can read consumed data.
2134  * Normally, the trace_iterator is used for reading the data when it is not
2135  * consumed, and must retain state.
2136  */
2137 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2138 {
2139 	memset_startat(iter, 0, seq);
2140 	iter->pos = -1;
2141 }
2142 
2143 /* Check the name is good for event/group/fields */
2144 static inline bool __is_good_name(const char *name, bool hash_ok)
2145 {
2146 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2147 		return false;
2148 	while (*++name != '\0') {
2149 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2150 		    (!hash_ok || *name != '-'))
2151 			return false;
2152 	}
2153 	return true;
2154 }
2155 
2156 /* Check the name is good for event/group/fields */
2157 static inline bool is_good_name(const char *name)
2158 {
2159 	return __is_good_name(name, false);
2160 }
2161 
2162 /* Check the name is good for system */
2163 static inline bool is_good_system_name(const char *name)
2164 {
2165 	return __is_good_name(name, true);
2166 }
2167 
2168 /* Convert certain expected symbols into '_' when generating event names */
2169 static inline void sanitize_event_name(char *name)
2170 {
2171 	while (*name++ != '\0')
2172 		if (*name == ':' || *name == '.')
2173 			*name = '_';
2174 }
2175 
2176 /*
2177  * This is a generic way to read and write a u64 value from a file in tracefs.
2178  *
2179  * The value is stored on the variable pointed by *val. The value needs
2180  * to be at least *min and at most *max. The write is protected by an
2181  * existing *lock.
2182  */
2183 struct trace_min_max_param {
2184 	struct mutex	*lock;
2185 	u64		*val;
2186 	u64		*min;
2187 	u64		*max;
2188 };
2189 
2190 #define U64_STR_SIZE		24	/* 20 digits max */
2191 
2192 extern const struct file_operations trace_min_max_fops;
2193 
2194 #ifdef CONFIG_RV
2195 extern int rv_init_interface(void);
2196 #else
2197 static inline int rv_init_interface(void)
2198 {
2199 	return 0;
2200 }
2201 #endif
2202 
2203 /*
2204  * This is used only to distinguish
2205  * function address from trampoline code.
2206  * So this value has no meaning.
2207  */
2208 #define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2209 
2210 #endif /* _LINUX_KERNEL_TRACE_H */
2211