xref: /linux/kernel/trace/trace.h (revision 34ea8fa084dd96a2e130ec871ade9ed3003f7eea)
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 struct trace_module_delta {
316 	struct rcu_head	rcu;
317 	long		delta[];
318 };
319 
320 /*
321  * The trace array - an array of per-CPU trace arrays. This is the
322  * highest level data structure that individual tracers deal with.
323  * They have on/off state as well:
324  */
325 struct trace_array {
326 	struct list_head	list;
327 	char			*name;
328 	struct array_buffer	array_buffer;
329 #ifdef CONFIG_TRACER_MAX_TRACE
330 	/*
331 	 * The max_buffer is used to snapshot the trace when a maximum
332 	 * latency is reached, or when the user initiates a snapshot.
333 	 * Some tracers will use this to store a maximum trace while
334 	 * it continues examining live traces.
335 	 *
336 	 * The buffers for the max_buffer are set up the same as the array_buffer
337 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
338 	 * with the buffer of the array_buffer and the buffers are reset for
339 	 * the array_buffer so the tracing can continue.
340 	 */
341 	struct array_buffer	max_buffer;
342 	bool			allocated_snapshot;
343 	spinlock_t		snapshot_trigger_lock;
344 	unsigned int		snapshot;
345 	unsigned long		max_latency;
346 #ifdef CONFIG_FSNOTIFY
347 	struct dentry		*d_max_latency;
348 	struct work_struct	fsnotify_work;
349 	struct irq_work		fsnotify_irqwork;
350 #endif
351 #endif
352 	/* The below is for memory mapped ring buffer */
353 	unsigned int		mapped;
354 	unsigned long		range_addr_start;
355 	unsigned long		range_addr_size;
356 	char			*range_name;
357 	long			text_delta;
358 	struct trace_module_delta *module_delta;
359 	void			*scratch; /* pointer in persistent memory */
360 	int			scratch_size;
361 
362 	int			buffer_disabled;
363 
364 	struct trace_pid_list	__rcu *filtered_pids;
365 	struct trace_pid_list	__rcu *filtered_no_pids;
366 	/*
367 	 * max_lock is used to protect the swapping of buffers
368 	 * when taking a max snapshot. The buffers themselves are
369 	 * protected by per_cpu spinlocks. But the action of the swap
370 	 * needs its own lock.
371 	 *
372 	 * This is defined as a arch_spinlock_t in order to help
373 	 * with performance when lockdep debugging is enabled.
374 	 *
375 	 * It is also used in other places outside the update_max_tr
376 	 * so it needs to be defined outside of the
377 	 * CONFIG_TRACER_MAX_TRACE.
378 	 */
379 	arch_spinlock_t		max_lock;
380 #ifdef CONFIG_FTRACE_SYSCALLS
381 	int			sys_refcount_enter;
382 	int			sys_refcount_exit;
383 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
384 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
385 #endif
386 	int			stop_count;
387 	int			clock_id;
388 	int			nr_topts;
389 	bool			clear_trace;
390 	int			buffer_percent;
391 	unsigned int		n_err_log_entries;
392 	struct tracer		*current_trace;
393 	unsigned int		trace_flags;
394 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
395 	unsigned int		flags;
396 	raw_spinlock_t		start_lock;
397 	const char		*system_names;
398 	struct list_head	err_log;
399 	struct dentry		*dir;
400 	struct dentry		*options;
401 	struct dentry		*percpu_dir;
402 	struct eventfs_inode	*event_dir;
403 	struct trace_options	*topts;
404 	struct list_head	systems;
405 	struct list_head	events;
406 	struct trace_event_file *trace_marker_file;
407 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
408 	/* one per_cpu trace_pipe can be opened by only one user */
409 	cpumask_var_t		pipe_cpumask;
410 	int			ref;
411 	int			trace_ref;
412 #ifdef CONFIG_MODULES
413 	struct list_head	mod_events;
414 #endif
415 #ifdef CONFIG_FUNCTION_TRACER
416 	struct ftrace_ops	*ops;
417 	struct trace_pid_list	__rcu *function_pids;
418 	struct trace_pid_list	__rcu *function_no_pids;
419 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
420 	struct fgraph_ops	*gops;
421 #endif
422 #ifdef CONFIG_DYNAMIC_FTRACE
423 	/* All of these are protected by the ftrace_lock */
424 	struct list_head	func_probes;
425 	struct list_head	mod_trace;
426 	struct list_head	mod_notrace;
427 #endif
428 	/* function tracing enabled */
429 	int			function_enabled;
430 #endif
431 	int			no_filter_buffering_ref;
432 	struct list_head	hist_vars;
433 #ifdef CONFIG_TRACER_SNAPSHOT
434 	struct cond_snapshot	*cond_snapshot;
435 #endif
436 	struct trace_func_repeats	__percpu *last_func_repeats;
437 	/*
438 	 * On boot up, the ring buffer is set to the minimum size, so that
439 	 * we do not waste memory on systems that are not using tracing.
440 	 */
441 	bool ring_buffer_expanded;
442 };
443 
444 enum {
445 	TRACE_ARRAY_FL_GLOBAL		= BIT(0),
446 	TRACE_ARRAY_FL_BOOT		= BIT(1),
447 	TRACE_ARRAY_FL_LAST_BOOT	= BIT(2),
448 	TRACE_ARRAY_FL_MOD_INIT		= BIT(3),
449 	TRACE_ARRAY_FL_MEMMAP		= BIT(4),
450 };
451 
452 #ifdef CONFIG_MODULES
453 bool module_exists(const char *module);
454 #else
455 static inline bool module_exists(const char *module)
456 {
457 	return false;
458 }
459 #endif
460 
461 extern struct list_head ftrace_trace_arrays;
462 
463 extern struct mutex trace_types_lock;
464 
465 extern int trace_array_get(struct trace_array *tr);
466 extern int tracing_check_open_get_tr(struct trace_array *tr);
467 extern struct trace_array *trace_array_find(const char *instance);
468 extern struct trace_array *trace_array_find_get(const char *instance);
469 
470 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
471 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
472 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
473 
474 extern bool trace_clock_in_ns(struct trace_array *tr);
475 
476 extern unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr);
477 
478 /*
479  * The global tracer (top) should be the first trace array added,
480  * but we check the flag anyway.
481  */
482 static inline struct trace_array *top_trace_array(void)
483 {
484 	struct trace_array *tr;
485 
486 	if (list_empty(&ftrace_trace_arrays))
487 		return NULL;
488 
489 	tr = list_entry(ftrace_trace_arrays.prev,
490 			typeof(*tr), list);
491 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
492 	return tr;
493 }
494 
495 #define FTRACE_CMP_TYPE(var, type) \
496 	__builtin_types_compatible_p(typeof(var), type *)
497 
498 #undef IF_ASSIGN
499 #define IF_ASSIGN(var, entry, etype, id)			\
500 	if (FTRACE_CMP_TYPE(var, etype)) {			\
501 		var = (typeof(var))(entry);			\
502 		WARN_ON(id != 0 && (entry)->type != id);	\
503 		break;						\
504 	}
505 
506 /* Will cause compile errors if type is not found. */
507 extern void __ftrace_bad_type(void);
508 
509 /*
510  * The trace_assign_type is a verifier that the entry type is
511  * the same as the type being assigned. To add new types simply
512  * add a line with the following format:
513  *
514  * IF_ASSIGN(var, ent, type, id);
515  *
516  *  Where "type" is the trace type that includes the trace_entry
517  *  as the "ent" item. And "id" is the trace identifier that is
518  *  used in the trace_type enum.
519  *
520  *  If the type can have more than one id, then use zero.
521  */
522 #define trace_assign_type(var, ent)					\
523 	do {								\
524 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
525 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
526 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
527 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
528 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
529 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
530 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
531 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
532 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
533 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
534 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
535 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
536 			  TRACE_MMIO_RW);				\
537 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
538 			  TRACE_MMIO_MAP);				\
539 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
540 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
541 			  TRACE_GRAPH_ENT);		\
542 		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
543 			  TRACE_GRAPH_RETADDR_ENT);		\
544 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
545 			  TRACE_GRAPH_RET);		\
546 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
547 			  TRACE_FUNC_REPEATS);				\
548 		__ftrace_bad_type();					\
549 	} while (0)
550 
551 /*
552  * An option specific to a tracer. This is a boolean value.
553  * The bit is the bit index that sets its value on the
554  * flags value in struct tracer_flags.
555  */
556 struct tracer_opt {
557 	const char	*name; /* Will appear on the trace_options file */
558 	u32		bit; /* Mask assigned in val field in tracer_flags */
559 };
560 
561 /*
562  * The set of specific options for a tracer. Your tracer
563  * have to set the initial value of the flags val.
564  */
565 struct tracer_flags {
566 	u32			val;
567 	struct tracer_opt	*opts;
568 	struct tracer		*trace;
569 };
570 
571 /* Makes more easy to define a tracer opt */
572 #define TRACER_OPT(s, b)	.name = #s, .bit = b
573 
574 
575 struct trace_option_dentry {
576 	struct tracer_opt		*opt;
577 	struct tracer_flags		*flags;
578 	struct trace_array		*tr;
579 	struct dentry			*entry;
580 };
581 
582 /**
583  * struct tracer - a specific tracer and its callbacks to interact with tracefs
584  * @name: the name chosen to select it on the available_tracers file
585  * @init: called when one switches to this tracer (echo name > current_tracer)
586  * @reset: called when one switches to another tracer
587  * @start: called when tracing is unpaused (echo 1 > tracing_on)
588  * @stop: called when tracing is paused (echo 0 > tracing_on)
589  * @update_thresh: called when tracing_thresh is updated
590  * @open: called when the trace file is opened
591  * @pipe_open: called when the trace_pipe file is opened
592  * @close: called when the trace file is released
593  * @pipe_close: called when the trace_pipe file is released
594  * @read: override the default read callback on trace_pipe
595  * @splice_read: override the default splice_read callback on trace_pipe
596  * @selftest: selftest to run on boot (see trace_selftest.c)
597  * @print_headers: override the first lines that describe your columns
598  * @print_line: callback that prints a trace
599  * @set_flag: signals one of your private flags changed (trace_options file)
600  * @flags: your private flags
601  */
602 struct tracer {
603 	const char		*name;
604 	int			(*init)(struct trace_array *tr);
605 	void			(*reset)(struct trace_array *tr);
606 	void			(*start)(struct trace_array *tr);
607 	void			(*stop)(struct trace_array *tr);
608 	int			(*update_thresh)(struct trace_array *tr);
609 	void			(*open)(struct trace_iterator *iter);
610 	void			(*pipe_open)(struct trace_iterator *iter);
611 	void			(*close)(struct trace_iterator *iter);
612 	void			(*pipe_close)(struct trace_iterator *iter);
613 	ssize_t			(*read)(struct trace_iterator *iter,
614 					struct file *filp, char __user *ubuf,
615 					size_t cnt, loff_t *ppos);
616 	ssize_t			(*splice_read)(struct trace_iterator *iter,
617 					       struct file *filp,
618 					       loff_t *ppos,
619 					       struct pipe_inode_info *pipe,
620 					       size_t len,
621 					       unsigned int flags);
622 #ifdef CONFIG_FTRACE_STARTUP_TEST
623 	int			(*selftest)(struct tracer *trace,
624 					    struct trace_array *tr);
625 #endif
626 	void			(*print_header)(struct seq_file *m);
627 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
628 	/* If you handled the flag setting, return 0 */
629 	int			(*set_flag)(struct trace_array *tr,
630 					    u32 old_flags, u32 bit, int set);
631 	/* Return 0 if OK with change, else return non-zero */
632 	int			(*flag_changed)(struct trace_array *tr,
633 						u32 mask, int set);
634 	struct tracer		*next;
635 	struct tracer_flags	*flags;
636 	int			enabled;
637 	bool			print_max;
638 	bool			allow_instances;
639 #ifdef CONFIG_TRACER_MAX_TRACE
640 	bool			use_max_tr;
641 #endif
642 	/* True if tracer cannot be enabled in kernel param */
643 	bool			noboot;
644 };
645 
646 static inline struct ring_buffer_iter *
647 trace_buffer_iter(struct trace_iterator *iter, int cpu)
648 {
649 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
650 }
651 
652 int tracer_init(struct tracer *t, struct trace_array *tr);
653 int tracing_is_enabled(void);
654 void tracing_reset_online_cpus(struct array_buffer *buf);
655 void tracing_reset_all_online_cpus(void);
656 void tracing_reset_all_online_cpus_unlocked(void);
657 int tracing_open_generic(struct inode *inode, struct file *filp);
658 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
659 int tracing_release_generic_tr(struct inode *inode, struct file *file);
660 int tracing_open_file_tr(struct inode *inode, struct file *filp);
661 int tracing_release_file_tr(struct inode *inode, struct file *filp);
662 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
663 bool tracing_is_disabled(void);
664 bool tracer_tracing_is_on(struct trace_array *tr);
665 void tracer_tracing_on(struct trace_array *tr);
666 void tracer_tracing_off(struct trace_array *tr);
667 struct dentry *trace_create_file(const char *name,
668 				 umode_t mode,
669 				 struct dentry *parent,
670 				 void *data,
671 				 const struct file_operations *fops);
672 
673 int tracing_init_dentry(void);
674 
675 struct ring_buffer_event;
676 
677 struct ring_buffer_event *
678 trace_buffer_lock_reserve(struct trace_buffer *buffer,
679 			  int type,
680 			  unsigned long len,
681 			  unsigned int trace_ctx);
682 
683 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
684 
685 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
686 						struct trace_array_cpu *data);
687 
688 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
689 					  int *ent_cpu, u64 *ent_ts);
690 
691 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
692 					struct ring_buffer_event *event);
693 
694 bool trace_is_tracepoint_string(const char *str);
695 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
696 char *trace_iter_expand_format(struct trace_iterator *iter);
697 bool ignore_event(struct trace_iterator *iter);
698 
699 int trace_empty(struct trace_iterator *iter);
700 
701 void *trace_find_next_entry_inc(struct trace_iterator *iter);
702 
703 void trace_init_global_iter(struct trace_iterator *iter);
704 
705 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
706 
707 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
708 unsigned long trace_total_entries(struct trace_array *tr);
709 
710 void trace_function(struct trace_array *tr,
711 		    unsigned long ip,
712 		    unsigned long parent_ip,
713 		    unsigned int trace_ctx);
714 void trace_graph_function(struct trace_array *tr,
715 		    unsigned long ip,
716 		    unsigned long parent_ip,
717 		    unsigned int trace_ctx);
718 void trace_latency_header(struct seq_file *m);
719 void trace_default_header(struct seq_file *m);
720 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
721 
722 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
723 			struct ftrace_regs *fregs);
724 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
725 		      struct ftrace_regs *fregs);
726 
727 void tracing_start_cmdline_record(void);
728 void tracing_stop_cmdline_record(void);
729 void tracing_start_tgid_record(void);
730 void tracing_stop_tgid_record(void);
731 
732 int register_tracer(struct tracer *type);
733 int is_tracing_stopped(void);
734 
735 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
736 
737 extern cpumask_var_t __read_mostly tracing_buffer_mask;
738 
739 #define for_each_tracing_cpu(cpu)	\
740 	for_each_cpu(cpu, tracing_buffer_mask)
741 
742 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
743 
744 extern unsigned long tracing_thresh;
745 
746 /* PID filtering */
747 
748 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
749 			     pid_t search_pid);
750 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
751 			    struct trace_pid_list *filtered_no_pids,
752 			    struct task_struct *task);
753 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
754 				  struct task_struct *self,
755 				  struct task_struct *task);
756 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
757 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
758 int trace_pid_show(struct seq_file *m, void *v);
759 int trace_pid_write(struct trace_pid_list *filtered_pids,
760 		    struct trace_pid_list **new_pid_list,
761 		    const char __user *ubuf, size_t cnt);
762 
763 #ifdef CONFIG_TRACER_MAX_TRACE
764 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
765 		   void *cond_data);
766 void update_max_tr_single(struct trace_array *tr,
767 			  struct task_struct *tsk, int cpu);
768 
769 #ifdef CONFIG_FSNOTIFY
770 #define LATENCY_FS_NOTIFY
771 #endif
772 #endif /* CONFIG_TRACER_MAX_TRACE */
773 
774 #ifdef LATENCY_FS_NOTIFY
775 void latency_fsnotify(struct trace_array *tr);
776 #else
777 static inline void latency_fsnotify(struct trace_array *tr) { }
778 #endif
779 
780 #ifdef CONFIG_STACKTRACE
781 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
782 #else
783 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
784 				 int skip)
785 {
786 }
787 #endif /* CONFIG_STACKTRACE */
788 
789 void trace_last_func_repeats(struct trace_array *tr,
790 			     struct trace_func_repeats *last_info,
791 			     unsigned int trace_ctx);
792 
793 extern u64 ftrace_now(int cpu);
794 
795 extern void trace_find_cmdline(int pid, char comm[]);
796 extern int trace_find_tgid(int pid);
797 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
798 
799 extern int trace_events_enabled(struct trace_array *tr, const char *system);
800 
801 #ifdef CONFIG_DYNAMIC_FTRACE
802 extern unsigned long ftrace_update_tot_cnt;
803 extern unsigned long ftrace_number_of_pages;
804 extern unsigned long ftrace_number_of_groups;
805 extern u64 ftrace_update_time;
806 extern u64 ftrace_total_mod_time;
807 void ftrace_init_trace_array(struct trace_array *tr);
808 #else
809 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
810 #endif
811 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
812 extern int DYN_FTRACE_TEST_NAME(void);
813 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
814 extern int DYN_FTRACE_TEST_NAME2(void);
815 
816 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
817 extern bool tracing_selftest_disabled;
818 
819 #ifdef CONFIG_FTRACE_STARTUP_TEST
820 extern void __init disable_tracing_selftest(const char *reason);
821 
822 extern int trace_selftest_startup_function(struct tracer *trace,
823 					   struct trace_array *tr);
824 extern int trace_selftest_startup_function_graph(struct tracer *trace,
825 						 struct trace_array *tr);
826 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
827 					  struct trace_array *tr);
828 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
829 					     struct trace_array *tr);
830 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
831 						 struct trace_array *tr);
832 extern int trace_selftest_startup_wakeup(struct tracer *trace,
833 					 struct trace_array *tr);
834 extern int trace_selftest_startup_nop(struct tracer *trace,
835 					 struct trace_array *tr);
836 extern int trace_selftest_startup_branch(struct tracer *trace,
837 					 struct trace_array *tr);
838 /*
839  * Tracer data references selftest functions that only occur
840  * on boot up. These can be __init functions. Thus, when selftests
841  * are enabled, then the tracers need to reference __init functions.
842  */
843 #define __tracer_data		__refdata
844 #else
845 static inline void __init disable_tracing_selftest(const char *reason)
846 {
847 }
848 /* Tracers are seldom changed. Optimize when selftests are disabled. */
849 #define __tracer_data		__read_mostly
850 #endif /* CONFIG_FTRACE_STARTUP_TEST */
851 
852 extern void *head_page(struct trace_array_cpu *data);
853 extern unsigned long long ns2usecs(u64 nsec);
854 extern int
855 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
856 extern int
857 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
858 extern int
859 trace_array_vprintk(struct trace_array *tr,
860 		    unsigned long ip, const char *fmt, va_list args);
861 int trace_array_printk_buf(struct trace_buffer *buffer,
862 			   unsigned long ip, const char *fmt, ...);
863 void trace_printk_seq(struct trace_seq *s);
864 enum print_line_t print_trace_line(struct trace_iterator *iter);
865 
866 extern char trace_find_mark(unsigned long long duration);
867 
868 struct ftrace_hash;
869 
870 struct ftrace_mod_load {
871 	struct list_head	list;
872 	char			*func;
873 	char			*module;
874 	int			 enable;
875 };
876 
877 enum {
878 	FTRACE_HASH_FL_MOD	= (1 << 0),
879 };
880 
881 struct ftrace_hash {
882 	unsigned long		size_bits;
883 	struct hlist_head	*buckets;
884 	unsigned long		count;
885 	unsigned long		flags;
886 	struct rcu_head		rcu;
887 };
888 
889 struct ftrace_func_entry *
890 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
891 
892 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
893 {
894 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
895 }
896 
897 /* Standard output formatting function used for function return traces */
898 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
899 
900 /* Flag options */
901 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
902 #define TRACE_GRAPH_PRINT_CPU           0x2
903 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
904 #define TRACE_GRAPH_PRINT_PROC          0x8
905 #define TRACE_GRAPH_PRINT_DURATION      0x10
906 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
907 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
908 #define TRACE_GRAPH_PRINT_IRQS          0x80
909 #define TRACE_GRAPH_PRINT_TAIL          0x100
910 #define TRACE_GRAPH_SLEEP_TIME          0x200
911 #define TRACE_GRAPH_GRAPH_TIME          0x400
912 #define TRACE_GRAPH_PRINT_RETVAL        0x800
913 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
914 #define TRACE_GRAPH_PRINT_RETADDR       0x2000
915 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
916 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
917 
918 extern void ftrace_graph_sleep_time_control(bool enable);
919 
920 #ifdef CONFIG_FUNCTION_PROFILER
921 extern void ftrace_graph_graph_time_control(bool enable);
922 #else
923 static inline void ftrace_graph_graph_time_control(bool enable) { }
924 #endif
925 
926 extern enum print_line_t
927 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
928 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
929 extern void
930 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
931 extern void graph_trace_open(struct trace_iterator *iter);
932 extern void graph_trace_close(struct trace_iterator *iter);
933 extern int __trace_graph_entry(struct trace_array *tr,
934 			       struct ftrace_graph_ent *trace,
935 			       unsigned int trace_ctx);
936 extern int __trace_graph_retaddr_entry(struct trace_array *tr,
937 				struct ftrace_graph_ent *trace,
938 				unsigned int trace_ctx,
939 				unsigned long retaddr);
940 extern void __trace_graph_return(struct trace_array *tr,
941 				 struct ftrace_graph_ret *trace,
942 				 unsigned int trace_ctx,
943 				 u64 calltime, u64 rettime);
944 
945 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
946 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
947 extern void free_fgraph_ops(struct trace_array *tr);
948 
949 enum {
950 	TRACE_GRAPH_FL		= 1,
951 
952 	/*
953 	 * In the very unlikely case that an interrupt came in
954 	 * at a start of graph tracing, and we want to trace
955 	 * the function in that interrupt, the depth can be greater
956 	 * than zero, because of the preempted start of a previous
957 	 * trace. In an even more unlikely case, depth could be 2
958 	 * if a softirq interrupted the start of graph tracing,
959 	 * followed by an interrupt preempting a start of graph
960 	 * tracing in the softirq, and depth can even be 3
961 	 * if an NMI came in at the start of an interrupt function
962 	 * that preempted a softirq start of a function that
963 	 * preempted normal context!!!! Luckily, it can't be
964 	 * greater than 3, so the next two bits are a mask
965 	 * of what the depth is when we set TRACE_GRAPH_FL
966 	 */
967 
968 	TRACE_GRAPH_DEPTH_START_BIT,
969 	TRACE_GRAPH_DEPTH_END_BIT,
970 
971 	/*
972 	 * To implement set_graph_notrace, if this bit is set, we ignore
973 	 * function graph tracing of called functions, until the return
974 	 * function is called to clear it.
975 	 */
976 	TRACE_GRAPH_NOTRACE_BIT,
977 };
978 
979 #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
980 
981 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
982 {
983 	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
984 }
985 
986 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
987 {
988 	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
989 	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
990 }
991 
992 #ifdef CONFIG_DYNAMIC_FTRACE
993 extern struct ftrace_hash __rcu *ftrace_graph_hash;
994 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
995 
996 static inline int
997 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
998 {
999 	unsigned long addr = trace->func;
1000 	int ret = 0;
1001 	struct ftrace_hash *hash;
1002 
1003 	preempt_disable_notrace();
1004 
1005 	/*
1006 	 * Have to open code "rcu_dereference_sched()" because the
1007 	 * function graph tracer can be called when RCU is not
1008 	 * "watching".
1009 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1010 	 */
1011 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
1012 
1013 	if (ftrace_hash_empty(hash)) {
1014 		ret = 1;
1015 		goto out;
1016 	}
1017 
1018 	if (ftrace_lookup_ip(hash, addr)) {
1019 		/*
1020 		 * This needs to be cleared on the return functions
1021 		 * when the depth is zero.
1022 		 */
1023 		*task_var |= TRACE_GRAPH_FL;
1024 		ftrace_graph_set_depth(task_var, trace->depth);
1025 
1026 		/*
1027 		 * If no irqs are to be traced, but a set_graph_function
1028 		 * is set, and called by an interrupt handler, we still
1029 		 * want to trace it.
1030 		 */
1031 		if (in_hardirq())
1032 			trace_recursion_set(TRACE_IRQ_BIT);
1033 		else
1034 			trace_recursion_clear(TRACE_IRQ_BIT);
1035 		ret = 1;
1036 	}
1037 
1038 out:
1039 	preempt_enable_notrace();
1040 	return ret;
1041 }
1042 
1043 static inline void
1044 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1045 {
1046 	unsigned long *task_var = fgraph_get_task_var(gops);
1047 
1048 	if ((*task_var & TRACE_GRAPH_FL) &&
1049 	    trace->depth == ftrace_graph_depth(task_var))
1050 		*task_var &= ~TRACE_GRAPH_FL;
1051 }
1052 
1053 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1054 {
1055 	int ret = 0;
1056 	struct ftrace_hash *notrace_hash;
1057 
1058 	preempt_disable_notrace();
1059 
1060 	/*
1061 	 * Have to open code "rcu_dereference_sched()" because the
1062 	 * function graph tracer can be called when RCU is not
1063 	 * "watching".
1064 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1065 	 */
1066 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1067 						 !preemptible());
1068 
1069 	if (ftrace_lookup_ip(notrace_hash, addr))
1070 		ret = 1;
1071 
1072 	preempt_enable_notrace();
1073 	return ret;
1074 }
1075 #else
1076 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1077 {
1078 	return 1;
1079 }
1080 
1081 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1082 {
1083 	return 0;
1084 }
1085 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1086 { }
1087 #endif /* CONFIG_DYNAMIC_FTRACE */
1088 
1089 extern unsigned int fgraph_max_depth;
1090 extern bool fgraph_sleep_time;
1091 
1092 static inline bool
1093 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1094 {
1095 	unsigned long *task_var = fgraph_get_task_var(gops);
1096 
1097 	/* trace it when it is-nested-in or is a function enabled. */
1098 	return !((*task_var & TRACE_GRAPH_FL) ||
1099 		 ftrace_graph_addr(task_var, trace)) ||
1100 		(trace->depth < 0) ||
1101 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1102 }
1103 
1104 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1105 		     struct ftrace_ops *src_ops);
1106 
1107 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1108 static inline enum print_line_t
1109 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1110 {
1111 	return TRACE_TYPE_UNHANDLED;
1112 }
1113 static inline void free_fgraph_ops(struct trace_array *tr) { }
1114 /* ftrace_ops may not be defined */
1115 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1116 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1117 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1118 
1119 extern struct list_head ftrace_pids;
1120 
1121 #ifdef CONFIG_FUNCTION_TRACER
1122 
1123 #define FTRACE_PID_IGNORE	-1
1124 #define FTRACE_PID_TRACE	-2
1125 
1126 struct ftrace_func_command {
1127 	struct list_head	list;
1128 	char			*name;
1129 	int			(*func)(struct trace_array *tr,
1130 					struct ftrace_hash *hash,
1131 					char *func, char *cmd,
1132 					char *params, int enable);
1133 };
1134 extern bool ftrace_filter_param __initdata;
1135 static inline int ftrace_trace_task(struct trace_array *tr)
1136 {
1137 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1138 		FTRACE_PID_IGNORE;
1139 }
1140 extern int ftrace_is_dead(void);
1141 int ftrace_create_function_files(struct trace_array *tr,
1142 				 struct dentry *parent);
1143 void ftrace_destroy_function_files(struct trace_array *tr);
1144 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1145 void ftrace_free_ftrace_ops(struct trace_array *tr);
1146 void ftrace_init_global_array_ops(struct trace_array *tr);
1147 struct trace_array *trace_get_global_array(void);
1148 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1149 void ftrace_reset_array_ops(struct trace_array *tr);
1150 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1151 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1152 				  struct dentry *d_tracer);
1153 void ftrace_clear_pids(struct trace_array *tr);
1154 int init_function_trace(void);
1155 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1156 #else
1157 static inline int ftrace_trace_task(struct trace_array *tr)
1158 {
1159 	return 1;
1160 }
1161 static inline int ftrace_is_dead(void) { return 0; }
1162 static inline int
1163 ftrace_create_function_files(struct trace_array *tr,
1164 			     struct dentry *parent)
1165 {
1166 	return 0;
1167 }
1168 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1169 {
1170 	return 0;
1171 }
1172 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1173 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1174 static inline __init void
1175 ftrace_init_global_array_ops(struct trace_array *tr) { }
1176 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1177 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1178 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1179 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1180 static inline int init_function_trace(void) { return 0; }
1181 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1182 /* ftace_func_t type is not defined, use macro instead of static inline */
1183 #define ftrace_init_array_ops(tr, func) do { } while (0)
1184 #endif /* CONFIG_FUNCTION_TRACER */
1185 
1186 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1187 
1188 struct ftrace_probe_ops {
1189 	void			(*func)(unsigned long ip,
1190 					unsigned long parent_ip,
1191 					struct trace_array *tr,
1192 					struct ftrace_probe_ops *ops,
1193 					void *data);
1194 	int			(*init)(struct ftrace_probe_ops *ops,
1195 					struct trace_array *tr,
1196 					unsigned long ip, void *init_data,
1197 					void **data);
1198 	void			(*free)(struct ftrace_probe_ops *ops,
1199 					struct trace_array *tr,
1200 					unsigned long ip, void *data);
1201 	int			(*print)(struct seq_file *m,
1202 					 unsigned long ip,
1203 					 struct ftrace_probe_ops *ops,
1204 					 void *data);
1205 };
1206 
1207 struct ftrace_func_mapper;
1208 typedef int (*ftrace_mapper_func)(void *data);
1209 
1210 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1211 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1212 					   unsigned long ip);
1213 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1214 			       unsigned long ip, void *data);
1215 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1216 				   unsigned long ip);
1217 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1218 			     ftrace_mapper_func free_func);
1219 
1220 extern int
1221 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1222 			       struct ftrace_probe_ops *ops, void *data);
1223 extern int
1224 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1225 				      struct ftrace_probe_ops *ops);
1226 extern void clear_ftrace_function_probes(struct trace_array *tr);
1227 
1228 int register_ftrace_command(struct ftrace_func_command *cmd);
1229 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1230 
1231 void ftrace_create_filter_files(struct ftrace_ops *ops,
1232 				struct dentry *parent);
1233 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1234 
1235 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1236 			     int len, int reset);
1237 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1238 			      int len, int reset);
1239 #else
1240 struct ftrace_func_command;
1241 
1242 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1243 {
1244 	return -EINVAL;
1245 }
1246 static inline __init int unregister_ftrace_command(char *cmd_name)
1247 {
1248 	return -EINVAL;
1249 }
1250 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1251 {
1252 }
1253 
1254 /*
1255  * The ops parameter passed in is usually undefined.
1256  * This must be a macro.
1257  */
1258 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1259 #define ftrace_destroy_filter_files(ops) do { } while (0)
1260 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1261 
1262 bool ftrace_event_is_function(struct trace_event_call *call);
1263 
1264 /*
1265  * struct trace_parser - servers for reading the user input separated by spaces
1266  * @cont: set if the input is not complete - no final space char was found
1267  * @buffer: holds the parsed user input
1268  * @idx: user input length
1269  * @size: buffer size
1270  */
1271 struct trace_parser {
1272 	bool		cont;
1273 	char		*buffer;
1274 	unsigned	idx;
1275 	unsigned	size;
1276 };
1277 
1278 static inline bool trace_parser_loaded(struct trace_parser *parser)
1279 {
1280 	return (parser->idx != 0);
1281 }
1282 
1283 static inline bool trace_parser_cont(struct trace_parser *parser)
1284 {
1285 	return parser->cont;
1286 }
1287 
1288 static inline void trace_parser_clear(struct trace_parser *parser)
1289 {
1290 	parser->cont = false;
1291 	parser->idx = 0;
1292 }
1293 
1294 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1295 extern void trace_parser_put(struct trace_parser *parser);
1296 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1297 	size_t cnt, loff_t *ppos);
1298 
1299 /*
1300  * Only create function graph options if function graph is configured.
1301  */
1302 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1303 # define FGRAPH_FLAGS						\
1304 		C(DISPLAY_GRAPH,	"display-graph"),
1305 #else
1306 # define FGRAPH_FLAGS
1307 #endif
1308 
1309 #ifdef CONFIG_BRANCH_TRACER
1310 # define BRANCH_FLAGS					\
1311 		C(BRANCH,		"branch"),
1312 #else
1313 # define BRANCH_FLAGS
1314 #endif
1315 
1316 #ifdef CONFIG_FUNCTION_TRACER
1317 # define FUNCTION_FLAGS						\
1318 		C(FUNCTION,		"function-trace"),	\
1319 		C(FUNC_FORK,		"function-fork"),
1320 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1321 #else
1322 # define FUNCTION_FLAGS
1323 # define FUNCTION_DEFAULT_FLAGS		0UL
1324 # define TRACE_ITER_FUNC_FORK		0UL
1325 #endif
1326 
1327 #ifdef CONFIG_STACKTRACE
1328 # define STACK_FLAGS				\
1329 		C(STACKTRACE,		"stacktrace"),
1330 #else
1331 # define STACK_FLAGS
1332 #endif
1333 
1334 /*
1335  * trace_iterator_flags is an enumeration that defines bit
1336  * positions into trace_flags that controls the output.
1337  *
1338  * NOTE: These bits must match the trace_options array in
1339  *       trace.c (this macro guarantees it).
1340  */
1341 #define TRACE_FLAGS						\
1342 		C(PRINT_PARENT,		"print-parent"),	\
1343 		C(SYM_OFFSET,		"sym-offset"),		\
1344 		C(SYM_ADDR,		"sym-addr"),		\
1345 		C(VERBOSE,		"verbose"),		\
1346 		C(RAW,			"raw"),			\
1347 		C(HEX,			"hex"),			\
1348 		C(BIN,			"bin"),			\
1349 		C(BLOCK,		"block"),		\
1350 		C(FIELDS,		"fields"),		\
1351 		C(PRINTK,		"trace_printk"),	\
1352 		C(ANNOTATE,		"annotate"),		\
1353 		C(USERSTACKTRACE,	"userstacktrace"),	\
1354 		C(SYM_USEROBJ,		"sym-userobj"),		\
1355 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1356 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1357 		C(LATENCY_FMT,		"latency-format"),	\
1358 		C(RECORD_CMD,		"record-cmd"),		\
1359 		C(RECORD_TGID,		"record-tgid"),		\
1360 		C(OVERWRITE,		"overwrite"),		\
1361 		C(STOP_ON_FREE,		"disable_on_free"),	\
1362 		C(IRQ_INFO,		"irq-info"),		\
1363 		C(MARKERS,		"markers"),		\
1364 		C(EVENT_FORK,		"event-fork"),		\
1365 		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1366 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1367 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1368 		FUNCTION_FLAGS					\
1369 		FGRAPH_FLAGS					\
1370 		STACK_FLAGS					\
1371 		BRANCH_FLAGS
1372 
1373 /*
1374  * By defining C, we can make TRACE_FLAGS a list of bit names
1375  * that will define the bits for the flag masks.
1376  */
1377 #undef C
1378 #define C(a, b) TRACE_ITER_##a##_BIT
1379 
1380 enum trace_iterator_bits {
1381 	TRACE_FLAGS
1382 	/* Make sure we don't go more than we have bits for */
1383 	TRACE_ITER_LAST_BIT
1384 };
1385 
1386 /*
1387  * By redefining C, we can make TRACE_FLAGS a list of masks that
1388  * use the bits as defined above.
1389  */
1390 #undef C
1391 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1392 
1393 enum trace_iterator_flags { TRACE_FLAGS };
1394 
1395 /*
1396  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1397  * control the output of kernel symbols.
1398  */
1399 #define TRACE_ITER_SYM_MASK \
1400 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1401 
1402 extern struct tracer nop_trace;
1403 
1404 #ifdef CONFIG_BRANCH_TRACER
1405 extern int enable_branch_tracing(struct trace_array *tr);
1406 extern void disable_branch_tracing(void);
1407 static inline int trace_branch_enable(struct trace_array *tr)
1408 {
1409 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1410 		return enable_branch_tracing(tr);
1411 	return 0;
1412 }
1413 static inline void trace_branch_disable(void)
1414 {
1415 	/* due to races, always disable */
1416 	disable_branch_tracing();
1417 }
1418 #else
1419 static inline int trace_branch_enable(struct trace_array *tr)
1420 {
1421 	return 0;
1422 }
1423 static inline void trace_branch_disable(void)
1424 {
1425 }
1426 #endif /* CONFIG_BRANCH_TRACER */
1427 
1428 /* set ring buffers to default size if not already done so */
1429 int tracing_update_buffers(struct trace_array *tr);
1430 
1431 union trace_synth_field {
1432 	u8				as_u8;
1433 	u16				as_u16;
1434 	u32				as_u32;
1435 	u64				as_u64;
1436 	struct trace_dynamic_info	as_dynamic;
1437 };
1438 
1439 struct ftrace_event_field {
1440 	struct list_head	link;
1441 	const char		*name;
1442 	const char		*type;
1443 	int			filter_type;
1444 	int			offset;
1445 	int			size;
1446 	unsigned int		is_signed:1;
1447 	unsigned int		needs_test:1;
1448 	int			len;
1449 };
1450 
1451 struct prog_entry;
1452 
1453 struct event_filter {
1454 	struct prog_entry __rcu	*prog;
1455 	char			*filter_string;
1456 };
1457 
1458 struct event_subsystem {
1459 	struct list_head	list;
1460 	const char		*name;
1461 	struct event_filter	*filter;
1462 	int			ref_count;
1463 };
1464 
1465 struct trace_subsystem_dir {
1466 	struct list_head		list;
1467 	struct event_subsystem		*subsystem;
1468 	struct trace_array		*tr;
1469 	struct eventfs_inode		*ei;
1470 	int				ref_count;
1471 	int				nr_events;
1472 };
1473 
1474 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1475 				     struct trace_buffer *buffer,
1476 				     struct ring_buffer_event *event,
1477 				     unsigned int trcace_ctx,
1478 				     struct pt_regs *regs);
1479 
1480 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1481 					      struct trace_buffer *buffer,
1482 					      struct ring_buffer_event *event,
1483 					      unsigned int trace_ctx)
1484 {
1485 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1486 }
1487 
1488 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1489 int trace_save_cmdline(struct task_struct *tsk);
1490 int trace_create_savedcmd(void);
1491 int trace_alloc_tgid_map(void);
1492 void trace_free_saved_cmdlines_buffer(void);
1493 
1494 extern const struct file_operations tracing_saved_cmdlines_fops;
1495 extern const struct file_operations tracing_saved_tgids_fops;
1496 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1497 
1498 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1499 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1500 void trace_buffered_event_disable(void);
1501 void trace_buffered_event_enable(void);
1502 
1503 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1504 
1505 static inline void
1506 __trace_event_discard_commit(struct trace_buffer *buffer,
1507 			     struct ring_buffer_event *event)
1508 {
1509 	if (this_cpu_read(trace_buffered_event) == event) {
1510 		/* Simply release the temp buffer and enable preemption */
1511 		this_cpu_dec(trace_buffered_event_cnt);
1512 		preempt_enable_notrace();
1513 		return;
1514 	}
1515 	/* ring_buffer_discard_commit() enables preemption */
1516 	ring_buffer_discard_commit(buffer, event);
1517 }
1518 
1519 /*
1520  * Helper function for event_trigger_unlock_commit{_regs}().
1521  * If there are event triggers attached to this event that requires
1522  * filtering against its fields, then they will be called as the
1523  * entry already holds the field information of the current event.
1524  *
1525  * It also checks if the event should be discarded or not.
1526  * It is to be discarded if the event is soft disabled and the
1527  * event was only recorded to process triggers, or if the event
1528  * filter is active and this event did not match the filters.
1529  *
1530  * Returns true if the event is discarded, false otherwise.
1531  */
1532 static inline bool
1533 __event_trigger_test_discard(struct trace_event_file *file,
1534 			     struct trace_buffer *buffer,
1535 			     struct ring_buffer_event *event,
1536 			     void *entry,
1537 			     enum event_trigger_type *tt)
1538 {
1539 	unsigned long eflags = file->flags;
1540 
1541 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1542 		*tt = event_triggers_call(file, buffer, entry, event);
1543 
1544 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1545 				    EVENT_FILE_FL_FILTERED |
1546 				    EVENT_FILE_FL_PID_FILTER))))
1547 		return false;
1548 
1549 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1550 		goto discard;
1551 
1552 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1553 	    !filter_match_preds(file->filter, entry))
1554 		goto discard;
1555 
1556 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1557 	    trace_event_ignore_this_pid(file))
1558 		goto discard;
1559 
1560 	return false;
1561  discard:
1562 	__trace_event_discard_commit(buffer, event);
1563 	return true;
1564 }
1565 
1566 /**
1567  * event_trigger_unlock_commit - handle triggers and finish event commit
1568  * @file: The file pointer associated with the event
1569  * @buffer: The ring buffer that the event is being written to
1570  * @event: The event meta data in the ring buffer
1571  * @entry: The event itself
1572  * @trace_ctx: The tracing context flags.
1573  *
1574  * This is a helper function to handle triggers that require data
1575  * from the event itself. It also tests the event against filters and
1576  * if the event is soft disabled and should be discarded.
1577  */
1578 static inline void
1579 event_trigger_unlock_commit(struct trace_event_file *file,
1580 			    struct trace_buffer *buffer,
1581 			    struct ring_buffer_event *event,
1582 			    void *entry, unsigned int trace_ctx)
1583 {
1584 	enum event_trigger_type tt = ETT_NONE;
1585 
1586 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1587 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1588 
1589 	if (tt)
1590 		event_triggers_post_call(file, tt);
1591 }
1592 
1593 #define FILTER_PRED_INVALID	((unsigned short)-1)
1594 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1595 #define FILTER_PRED_FOLD	(1 << 15)
1596 
1597 /*
1598  * The max preds is the size of unsigned short with
1599  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1600  * and FOLD flags. The other is reserved.
1601  *
1602  * 2^14 preds is way more than enough.
1603  */
1604 #define MAX_FILTER_PRED		16384
1605 
1606 struct filter_pred;
1607 struct regex;
1608 
1609 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1610 
1611 enum regex_type {
1612 	MATCH_FULL = 0,
1613 	MATCH_FRONT_ONLY,
1614 	MATCH_MIDDLE_ONLY,
1615 	MATCH_END_ONLY,
1616 	MATCH_GLOB,
1617 	MATCH_INDEX,
1618 };
1619 
1620 struct regex {
1621 	char			pattern[MAX_FILTER_STR_VAL];
1622 	int			len;
1623 	int			field_len;
1624 	regex_match_func	match;
1625 };
1626 
1627 static inline bool is_string_field(struct ftrace_event_field *field)
1628 {
1629 	return field->filter_type == FILTER_DYN_STRING ||
1630 	       field->filter_type == FILTER_RDYN_STRING ||
1631 	       field->filter_type == FILTER_STATIC_STRING ||
1632 	       field->filter_type == FILTER_PTR_STRING ||
1633 	       field->filter_type == FILTER_COMM;
1634 }
1635 
1636 static inline bool is_function_field(struct ftrace_event_field *field)
1637 {
1638 	return field->filter_type == FILTER_TRACE_FN;
1639 }
1640 
1641 extern enum regex_type
1642 filter_parse_regex(char *buff, int len, char **search, int *not);
1643 extern void print_event_filter(struct trace_event_file *file,
1644 			       struct trace_seq *s);
1645 extern int apply_event_filter(struct trace_event_file *file,
1646 			      char *filter_string);
1647 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1648 					char *filter_string);
1649 extern void print_subsystem_event_filter(struct event_subsystem *system,
1650 					 struct trace_seq *s);
1651 extern int filter_assign_type(const char *type);
1652 extern int create_event_filter(struct trace_array *tr,
1653 			       struct trace_event_call *call,
1654 			       char *filter_str, bool set_str,
1655 			       struct event_filter **filterp);
1656 extern void free_event_filter(struct event_filter *filter);
1657 
1658 struct ftrace_event_field *
1659 trace_find_event_field(struct trace_event_call *call, char *name);
1660 
1661 extern void trace_event_enable_cmd_record(bool enable);
1662 extern void trace_event_enable_tgid_record(bool enable);
1663 
1664 extern int event_trace_init(void);
1665 extern int init_events(void);
1666 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1667 extern int event_trace_del_tracer(struct trace_array *tr);
1668 extern void __trace_early_add_events(struct trace_array *tr);
1669 
1670 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1671 						  const char *system,
1672 						  const char *event);
1673 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1674 						const char *system,
1675 						const char *event);
1676 
1677 static inline void *event_file_data(struct file *filp)
1678 {
1679 	return READ_ONCE(file_inode(filp)->i_private);
1680 }
1681 
1682 extern struct mutex event_mutex;
1683 extern struct list_head ftrace_events;
1684 
1685 /*
1686  * When the trace_event_file is the filp->i_private pointer,
1687  * it must be taken under the event_mutex lock, and then checked
1688  * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1689  * data pointed to by the trace_event_file can not be trusted.
1690  *
1691  * Use the event_file_file() to access the trace_event_file from
1692  * the filp the first time under the event_mutex and check for
1693  * NULL. If it is needed to be retrieved again and the event_mutex
1694  * is still held, then the event_file_data() can be used and it
1695  * is guaranteed to be valid.
1696  */
1697 static inline struct trace_event_file *event_file_file(struct file *filp)
1698 {
1699 	struct trace_event_file *file;
1700 
1701 	lockdep_assert_held(&event_mutex);
1702 	file = READ_ONCE(file_inode(filp)->i_private);
1703 	if (!file || file->flags & EVENT_FILE_FL_FREED)
1704 		return NULL;
1705 	return file;
1706 }
1707 
1708 extern const struct file_operations event_trigger_fops;
1709 extern const struct file_operations event_hist_fops;
1710 extern const struct file_operations event_hist_debug_fops;
1711 extern const struct file_operations event_inject_fops;
1712 
1713 #ifdef CONFIG_HIST_TRIGGERS
1714 extern int register_trigger_hist_cmd(void);
1715 extern int register_trigger_hist_enable_disable_cmds(void);
1716 #else
1717 static inline int register_trigger_hist_cmd(void) { return 0; }
1718 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1719 #endif
1720 
1721 extern int register_trigger_cmds(void);
1722 extern void clear_event_triggers(struct trace_array *tr);
1723 
1724 enum {
1725 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1726 };
1727 
1728 struct event_trigger_data {
1729 	unsigned long			count;
1730 	int				ref;
1731 	int				flags;
1732 	struct event_trigger_ops	*ops;
1733 	struct event_command		*cmd_ops;
1734 	struct event_filter __rcu	*filter;
1735 	char				*filter_str;
1736 	void				*private_data;
1737 	bool				paused;
1738 	bool				paused_tmp;
1739 	struct list_head		list;
1740 	char				*name;
1741 	struct list_head		named_list;
1742 	struct event_trigger_data	*named_data;
1743 };
1744 
1745 /* Avoid typos */
1746 #define ENABLE_EVENT_STR	"enable_event"
1747 #define DISABLE_EVENT_STR	"disable_event"
1748 #define ENABLE_HIST_STR		"enable_hist"
1749 #define DISABLE_HIST_STR	"disable_hist"
1750 
1751 struct enable_trigger_data {
1752 	struct trace_event_file		*file;
1753 	bool				enable;
1754 	bool				hist;
1755 };
1756 
1757 extern int event_enable_trigger_print(struct seq_file *m,
1758 				      struct event_trigger_data *data);
1759 extern void event_enable_trigger_free(struct event_trigger_data *data);
1760 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1761 				      struct trace_event_file *file,
1762 				      char *glob, char *cmd,
1763 				      char *param_and_filter);
1764 extern int event_enable_register_trigger(char *glob,
1765 					 struct event_trigger_data *data,
1766 					 struct trace_event_file *file);
1767 extern void event_enable_unregister_trigger(char *glob,
1768 					    struct event_trigger_data *test,
1769 					    struct trace_event_file *file);
1770 extern void trigger_data_free(struct event_trigger_data *data);
1771 extern int event_trigger_init(struct event_trigger_data *data);
1772 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1773 					      int trigger_enable);
1774 extern void update_cond_flag(struct trace_event_file *file);
1775 extern int set_trigger_filter(char *filter_str,
1776 			      struct event_trigger_data *trigger_data,
1777 			      struct trace_event_file *file);
1778 extern struct event_trigger_data *find_named_trigger(const char *name);
1779 extern bool is_named_trigger(struct event_trigger_data *test);
1780 extern int save_named_trigger(const char *name,
1781 			      struct event_trigger_data *data);
1782 extern void del_named_trigger(struct event_trigger_data *data);
1783 extern void pause_named_trigger(struct event_trigger_data *data);
1784 extern void unpause_named_trigger(struct event_trigger_data *data);
1785 extern void set_named_trigger_data(struct event_trigger_data *data,
1786 				   struct event_trigger_data *named_data);
1787 extern struct event_trigger_data *
1788 get_named_trigger_data(struct event_trigger_data *data);
1789 extern int register_event_command(struct event_command *cmd);
1790 extern int unregister_event_command(struct event_command *cmd);
1791 extern int register_trigger_hist_enable_disable_cmds(void);
1792 extern bool event_trigger_check_remove(const char *glob);
1793 extern bool event_trigger_empty_param(const char *param);
1794 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1795 					 char **filter, bool param_required);
1796 extern struct event_trigger_data *
1797 event_trigger_alloc(struct event_command *cmd_ops,
1798 		    char *cmd,
1799 		    char *param,
1800 		    void *private_data);
1801 extern int event_trigger_parse_num(char *trigger,
1802 				   struct event_trigger_data *trigger_data);
1803 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1804 				    struct trace_event_file *file,
1805 				    char *param,
1806 				    struct event_trigger_data *trigger_data);
1807 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1808 				       struct event_trigger_data *trigger_data);
1809 extern int event_trigger_register(struct event_command *cmd_ops,
1810 				  struct trace_event_file *file,
1811 				  char *glob,
1812 				  struct event_trigger_data *trigger_data);
1813 extern void event_trigger_unregister(struct event_command *cmd_ops,
1814 				     struct trace_event_file *file,
1815 				     char *glob,
1816 				     struct event_trigger_data *trigger_data);
1817 
1818 extern void event_file_get(struct trace_event_file *file);
1819 extern void event_file_put(struct trace_event_file *file);
1820 
1821 /**
1822  * struct event_trigger_ops - callbacks for trace event triggers
1823  *
1824  * The methods in this structure provide per-event trigger hooks for
1825  * various trigger operations.
1826  *
1827  * The @init and @free methods are used during trigger setup and
1828  * teardown, typically called from an event_command's @parse()
1829  * function implementation.
1830  *
1831  * The @print method is used to print the trigger spec.
1832  *
1833  * The @trigger method is the function that actually implements the
1834  * trigger and is called in the context of the triggering event
1835  * whenever that event occurs.
1836  *
1837  * All the methods below, except for @init() and @free(), must be
1838  * implemented.
1839  *
1840  * @trigger: The trigger 'probe' function called when the triggering
1841  *	event occurs.  The data passed into this callback is the data
1842  *	that was supplied to the event_command @reg() function that
1843  *	registered the trigger (see struct event_command) along with
1844  *	the trace record, rec.
1845  *
1846  * @init: An optional initialization function called for the trigger
1847  *	when the trigger is registered (via the event_command reg()
1848  *	function).  This can be used to perform per-trigger
1849  *	initialization such as incrementing a per-trigger reference
1850  *	count, for instance.  This is usually implemented by the
1851  *	generic utility function @event_trigger_init() (see
1852  *	trace_event_triggers.c).
1853  *
1854  * @free: An optional de-initialization function called for the
1855  *	trigger when the trigger is unregistered (via the
1856  *	event_command @reg() function).  This can be used to perform
1857  *	per-trigger de-initialization such as decrementing a
1858  *	per-trigger reference count and freeing corresponding trigger
1859  *	data, for instance.  This is usually implemented by the
1860  *	generic utility function @event_trigger_free() (see
1861  *	trace_event_triggers.c).
1862  *
1863  * @print: The callback function invoked to have the trigger print
1864  *	itself.  This is usually implemented by a wrapper function
1865  *	that calls the generic utility function @event_trigger_print()
1866  *	(see trace_event_triggers.c).
1867  */
1868 struct event_trigger_ops {
1869 	void			(*trigger)(struct event_trigger_data *data,
1870 					   struct trace_buffer *buffer,
1871 					   void *rec,
1872 					   struct ring_buffer_event *rbe);
1873 	int			(*init)(struct event_trigger_data *data);
1874 	void			(*free)(struct event_trigger_data *data);
1875 	int			(*print)(struct seq_file *m,
1876 					 struct event_trigger_data *data);
1877 };
1878 
1879 /**
1880  * struct event_command - callbacks and data members for event commands
1881  *
1882  * Event commands are invoked by users by writing the command name
1883  * into the 'trigger' file associated with a trace event.  The
1884  * parameters associated with a specific invocation of an event
1885  * command are used to create an event trigger instance, which is
1886  * added to the list of trigger instances associated with that trace
1887  * event.  When the event is hit, the set of triggers associated with
1888  * that event is invoked.
1889  *
1890  * The data members in this structure provide per-event command data
1891  * for various event commands.
1892  *
1893  * All the data members below, except for @post_trigger, must be set
1894  * for each event command.
1895  *
1896  * @name: The unique name that identifies the event command.  This is
1897  *	the name used when setting triggers via trigger files.
1898  *
1899  * @trigger_type: A unique id that identifies the event command
1900  *	'type'.  This value has two purposes, the first to ensure that
1901  *	only one trigger of the same type can be set at a given time
1902  *	for a particular event e.g. it doesn't make sense to have both
1903  *	a traceon and traceoff trigger attached to a single event at
1904  *	the same time, so traceon and traceoff have the same type
1905  *	though they have different names.  The @trigger_type value is
1906  *	also used as a bit value for deferring the actual trigger
1907  *	action until after the current event is finished.  Some
1908  *	commands need to do this if they themselves log to the trace
1909  *	buffer (see the @post_trigger() member below).  @trigger_type
1910  *	values are defined by adding new values to the trigger_type
1911  *	enum in include/linux/trace_events.h.
1912  *
1913  * @flags: See the enum event_command_flags below.
1914  *
1915  * All the methods below, except for @set_filter() and @unreg_all(),
1916  * must be implemented.
1917  *
1918  * @parse: The callback function responsible for parsing and
1919  *	registering the trigger written to the 'trigger' file by the
1920  *	user.  It allocates the trigger instance and registers it with
1921  *	the appropriate trace event.  It makes use of the other
1922  *	event_command callback functions to orchestrate this, and is
1923  *	usually implemented by the generic utility function
1924  *	@event_trigger_callback() (see trace_event_triggers.c).
1925  *
1926  * @reg: Adds the trigger to the list of triggers associated with the
1927  *	event, and enables the event trigger itself, after
1928  *	initializing it (via the event_trigger_ops @init() function).
1929  *	This is also where commands can use the @trigger_type value to
1930  *	make the decision as to whether or not multiple instances of
1931  *	the trigger should be allowed.  This is usually implemented by
1932  *	the generic utility function @register_trigger() (see
1933  *	trace_event_triggers.c).
1934  *
1935  * @unreg: Removes the trigger from the list of triggers associated
1936  *	with the event, and disables the event trigger itself, after
1937  *	initializing it (via the event_trigger_ops @free() function).
1938  *	This is usually implemented by the generic utility function
1939  *	@unregister_trigger() (see trace_event_triggers.c).
1940  *
1941  * @unreg_all: An optional function called to remove all the triggers
1942  *	from the list of triggers associated with the event.  Called
1943  *	when a trigger file is opened in truncate mode.
1944  *
1945  * @set_filter: An optional function called to parse and set a filter
1946  *	for the trigger.  If no @set_filter() method is set for the
1947  *	event command, filters set by the user for the command will be
1948  *	ignored.  This is usually implemented by the generic utility
1949  *	function @set_trigger_filter() (see trace_event_triggers.c).
1950  *
1951  * @get_trigger_ops: The callback function invoked to retrieve the
1952  *	event_trigger_ops implementation associated with the command.
1953  *	This callback function allows a single event_command to
1954  *	support multiple trigger implementations via different sets of
1955  *	event_trigger_ops, depending on the value of the @param
1956  *	string.
1957  */
1958 struct event_command {
1959 	struct list_head	list;
1960 	char			*name;
1961 	enum event_trigger_type	trigger_type;
1962 	int			flags;
1963 	int			(*parse)(struct event_command *cmd_ops,
1964 					 struct trace_event_file *file,
1965 					 char *glob, char *cmd,
1966 					 char *param_and_filter);
1967 	int			(*reg)(char *glob,
1968 				       struct event_trigger_data *data,
1969 				       struct trace_event_file *file);
1970 	void			(*unreg)(char *glob,
1971 					 struct event_trigger_data *data,
1972 					 struct trace_event_file *file);
1973 	void			(*unreg_all)(struct trace_event_file *file);
1974 	int			(*set_filter)(char *filter_str,
1975 					      struct event_trigger_data *data,
1976 					      struct trace_event_file *file);
1977 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1978 };
1979 
1980 /**
1981  * enum event_command_flags - flags for struct event_command
1982  *
1983  * @POST_TRIGGER: A flag that says whether or not this command needs
1984  *	to have its action delayed until after the current event has
1985  *	been closed.  Some triggers need to avoid being invoked while
1986  *	an event is currently in the process of being logged, since
1987  *	the trigger may itself log data into the trace buffer.  Thus
1988  *	we make sure the current event is committed before invoking
1989  *	those triggers.  To do that, the trigger invocation is split
1990  *	in two - the first part checks the filter using the current
1991  *	trace record; if a command has the @post_trigger flag set, it
1992  *	sets a bit for itself in the return value, otherwise it
1993  *	directly invokes the trigger.  Once all commands have been
1994  *	either invoked or set their return flag, the current record is
1995  *	either committed or discarded.  At that point, if any commands
1996  *	have deferred their triggers, those commands are finally
1997  *	invoked following the close of the current event.  In other
1998  *	words, if the event_trigger_ops @func() probe implementation
1999  *	itself logs to the trace buffer, this flag should be set,
2000  *	otherwise it can be left unspecified.
2001  *
2002  * @NEEDS_REC: A flag that says whether or not this command needs
2003  *	access to the trace record in order to perform its function,
2004  *	regardless of whether or not it has a filter associated with
2005  *	it (filters make a trigger require access to the trace record
2006  *	but are not always present).
2007  */
2008 enum event_command_flags {
2009 	EVENT_CMD_FL_POST_TRIGGER	= 1,
2010 	EVENT_CMD_FL_NEEDS_REC		= 2,
2011 };
2012 
2013 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
2014 {
2015 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
2016 }
2017 
2018 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
2019 {
2020 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
2021 }
2022 
2023 extern int trace_event_enable_disable(struct trace_event_file *file,
2024 				      int enable, int soft_disable);
2025 extern int tracing_alloc_snapshot(void);
2026 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
2027 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
2028 
2029 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
2030 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2031 
2032 extern const char *__start___trace_bprintk_fmt[];
2033 extern const char *__stop___trace_bprintk_fmt[];
2034 
2035 extern const char *__start___tracepoint_str[];
2036 extern const char *__stop___tracepoint_str[];
2037 
2038 void trace_printk_control(bool enabled);
2039 void trace_printk_start_comm(void);
2040 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2041 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2042 
2043 /* Used from boot time tracer */
2044 extern int trace_set_options(struct trace_array *tr, char *option);
2045 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2046 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2047 					  unsigned long size, int cpu_id);
2048 extern int tracing_set_cpumask(struct trace_array *tr,
2049 				cpumask_var_t tracing_cpumask_new);
2050 
2051 
2052 #define MAX_EVENT_NAME_LEN	64
2053 
2054 extern ssize_t trace_parse_run_command(struct file *file,
2055 		const char __user *buffer, size_t count, loff_t *ppos,
2056 		int (*createfn)(const char *));
2057 
2058 extern unsigned int err_pos(char *cmd, const char *str);
2059 extern void tracing_log_err(struct trace_array *tr,
2060 			    const char *loc, const char *cmd,
2061 			    const char **errs, u8 type, u16 pos);
2062 
2063 /*
2064  * Normal trace_printk() and friends allocates special buffers
2065  * to do the manipulation, as well as saves the print formats
2066  * into sections to display. But the trace infrastructure wants
2067  * to use these without the added overhead at the price of being
2068  * a bit slower (used mainly for warnings, where we don't care
2069  * about performance). The internal_trace_puts() is for such
2070  * a purpose.
2071  */
2072 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2073 
2074 #undef FTRACE_ENTRY
2075 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2076 	extern struct trace_event_call					\
2077 	__aligned(4) event_##call;
2078 #undef FTRACE_ENTRY_DUP
2079 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2080 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2081 #undef FTRACE_ENTRY_PACKED
2082 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2083 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2084 
2085 #include "trace_entries.h"
2086 
2087 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2088 int perf_ftrace_event_register(struct trace_event_call *call,
2089 			       enum trace_reg type, void *data);
2090 #else
2091 #define perf_ftrace_event_register NULL
2092 #endif
2093 
2094 #ifdef CONFIG_FTRACE_SYSCALLS
2095 void init_ftrace_syscalls(void);
2096 const char *get_syscall_name(int syscall);
2097 #else
2098 static inline void init_ftrace_syscalls(void) { }
2099 static inline const char *get_syscall_name(int syscall)
2100 {
2101 	return NULL;
2102 }
2103 #endif
2104 
2105 #ifdef CONFIG_EVENT_TRACING
2106 void trace_event_init(void);
2107 void trace_event_eval_update(struct trace_eval_map **map, int len);
2108 /* Used from boot time tracer */
2109 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2110 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2111 #else
2112 static inline void __init trace_event_init(void) { }
2113 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2114 #endif
2115 
2116 #ifdef CONFIG_TRACER_SNAPSHOT
2117 void tracing_snapshot_instance(struct trace_array *tr);
2118 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2119 int tracing_arm_snapshot(struct trace_array *tr);
2120 void tracing_disarm_snapshot(struct trace_array *tr);
2121 #else
2122 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2123 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2124 {
2125 	return 0;
2126 }
2127 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
2128 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2129 #endif
2130 
2131 #ifdef CONFIG_PREEMPT_TRACER
2132 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2133 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2134 #else
2135 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2136 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2137 #endif
2138 #ifdef CONFIG_IRQSOFF_TRACER
2139 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2140 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2141 #else
2142 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2143 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2144 #endif
2145 
2146 /*
2147  * Reset the state of the trace_iterator so that it can read consumed data.
2148  * Normally, the trace_iterator is used for reading the data when it is not
2149  * consumed, and must retain state.
2150  */
2151 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2152 {
2153 	memset_startat(iter, 0, seq);
2154 	iter->pos = -1;
2155 }
2156 
2157 /* Check the name is good for event/group/fields */
2158 static inline bool __is_good_name(const char *name, bool hash_ok)
2159 {
2160 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2161 		return false;
2162 	while (*++name != '\0') {
2163 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2164 		    (!hash_ok || *name != '-'))
2165 			return false;
2166 	}
2167 	return true;
2168 }
2169 
2170 /* Check the name is good for event/group/fields */
2171 static inline bool is_good_name(const char *name)
2172 {
2173 	return __is_good_name(name, false);
2174 }
2175 
2176 /* Check the name is good for system */
2177 static inline bool is_good_system_name(const char *name)
2178 {
2179 	return __is_good_name(name, true);
2180 }
2181 
2182 /* Convert certain expected symbols into '_' when generating event names */
2183 static inline void sanitize_event_name(char *name)
2184 {
2185 	while (*name++ != '\0')
2186 		if (*name == ':' || *name == '.')
2187 			*name = '_';
2188 }
2189 
2190 /*
2191  * This is a generic way to read and write a u64 value from a file in tracefs.
2192  *
2193  * The value is stored on the variable pointed by *val. The value needs
2194  * to be at least *min and at most *max. The write is protected by an
2195  * existing *lock.
2196  */
2197 struct trace_min_max_param {
2198 	struct mutex	*lock;
2199 	u64		*val;
2200 	u64		*min;
2201 	u64		*max;
2202 };
2203 
2204 #define U64_STR_SIZE		24	/* 20 digits max */
2205 
2206 extern const struct file_operations trace_min_max_fops;
2207 
2208 #ifdef CONFIG_RV
2209 extern int rv_init_interface(void);
2210 #else
2211 static inline int rv_init_interface(void)
2212 {
2213 	return 0;
2214 }
2215 #endif
2216 
2217 /*
2218  * This is used only to distinguish
2219  * function address from trampoline code.
2220  * So this value has no meaning.
2221  */
2222 #define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2223 
2224 #endif /* _LINUX_KERNEL_TRACE_H */
2225