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1 // SPDX-License-Identifier: GPL-2.0
2 
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5 
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24 
25 #include "pid_list.h"
26 
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h>		/* For NR_SYSCALLS	     */
29 #include <asm/syscall.h>	/* some archs define it here */
30 #endif
31 
32 #define TRACE_MODE_WRITE	0640
33 #define TRACE_MODE_READ		0440
34 
35 enum trace_type {
36 	__TRACE_FIRST_TYPE = 0,
37 
38 	TRACE_FN,
39 	TRACE_CTX,
40 	TRACE_WAKE,
41 	TRACE_STACK,
42 	TRACE_PRINT,
43 	TRACE_BPRINT,
44 	TRACE_MMIO_RW,
45 	TRACE_MMIO_MAP,
46 	TRACE_BRANCH,
47 	TRACE_GRAPH_RET,
48 	TRACE_GRAPH_ENT,
49 	TRACE_USER_STACK,
50 	TRACE_BLK,
51 	TRACE_BPUTS,
52 	TRACE_HWLAT,
53 	TRACE_OSNOISE,
54 	TRACE_TIMERLAT,
55 	TRACE_RAW_DATA,
56 	TRACE_FUNC_REPEATS,
57 
58 	__TRACE_LAST_TYPE,
59 };
60 
61 
62 #undef __field
63 #define __field(type, item)		type	item;
64 
65 #undef __field_fn
66 #define __field_fn(type, item)		type	item;
67 
68 #undef __field_struct
69 #define __field_struct(type, item)	__field(type, item)
70 
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73 
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76 
77 #undef __array
78 #define __array(type, item, size)	type	item[size];
79 
80 #undef __array_desc
81 #define __array_desc(type, container, item, size)
82 
83 #undef __dynamic_array
84 #define __dynamic_array(type, item)	type	item[];
85 
86 #undef __rel_dynamic_array
87 #define __rel_dynamic_array(type, item)	type	item[];
88 
89 #undef F_STRUCT
90 #define F_STRUCT(args...)		args
91 
92 #undef FTRACE_ENTRY
93 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
94 	struct struct_name {						\
95 		struct trace_entry	ent;				\
96 		tstruct							\
97 	}
98 
99 #undef FTRACE_ENTRY_DUP
100 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
101 
102 #undef FTRACE_ENTRY_REG
103 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
104 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
105 
106 #undef FTRACE_ENTRY_PACKED
107 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
108 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
109 
110 #include "trace_entries.h"
111 
112 /* Use this for memory failure errors */
113 #define MEM_FAIL(condition, fmt, ...)					\
114 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
115 
116 #define FAULT_STRING "(fault)"
117 
118 #define HIST_STACKTRACE_DEPTH	16
119 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
120 #define HIST_STACKTRACE_SKIP	5
121 
122 /*
123  * syscalls are special, and need special handling, this is why
124  * they are not included in trace_entries.h
125  */
126 struct syscall_trace_enter {
127 	struct trace_entry	ent;
128 	int			nr;
129 	unsigned long		args[];
130 };
131 
132 struct syscall_trace_exit {
133 	struct trace_entry	ent;
134 	int			nr;
135 	long			ret;
136 };
137 
138 struct kprobe_trace_entry_head {
139 	struct trace_entry	ent;
140 	unsigned long		ip;
141 };
142 
143 struct eprobe_trace_entry_head {
144 	struct trace_entry	ent;
145 	unsigned int		type;
146 };
147 
148 struct kretprobe_trace_entry_head {
149 	struct trace_entry	ent;
150 	unsigned long		func;
151 	unsigned long		ret_ip;
152 };
153 
154 #define TRACE_BUF_SIZE		1024
155 
156 struct trace_array;
157 
158 /*
159  * The CPU trace array - it consists of thousands of trace entries
160  * plus some other descriptor data: (for example which task started
161  * the trace, etc.)
162  */
163 struct trace_array_cpu {
164 	atomic_t		disabled;
165 	void			*buffer_page;	/* ring buffer spare */
166 
167 	unsigned long		entries;
168 	unsigned long		saved_latency;
169 	unsigned long		critical_start;
170 	unsigned long		critical_end;
171 	unsigned long		critical_sequence;
172 	unsigned long		nice;
173 	unsigned long		policy;
174 	unsigned long		rt_priority;
175 	unsigned long		skipped_entries;
176 	u64			preempt_timestamp;
177 	pid_t			pid;
178 	kuid_t			uid;
179 	char			comm[TASK_COMM_LEN];
180 
181 #ifdef CONFIG_FUNCTION_TRACER
182 	int			ftrace_ignore_pid;
183 #endif
184 	bool			ignore_pid;
185 };
186 
187 struct tracer;
188 struct trace_option_dentry;
189 
190 struct array_buffer {
191 	struct trace_array		*tr;
192 	struct trace_buffer		*buffer;
193 	struct trace_array_cpu __percpu	*data;
194 	u64				time_start;
195 	int				cpu;
196 };
197 
198 #define TRACE_FLAGS_MAX_SIZE		32
199 
200 struct trace_options {
201 	struct tracer			*tracer;
202 	struct trace_option_dentry	*topts;
203 };
204 
205 struct trace_pid_list *trace_pid_list_alloc(void);
206 void trace_pid_list_free(struct trace_pid_list *pid_list);
207 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
208 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
209 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
210 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
211 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
212 			unsigned int *next);
213 
214 enum {
215 	TRACE_PIDS		= BIT(0),
216 	TRACE_NO_PIDS		= BIT(1),
217 };
218 
pid_type_enabled(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)219 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
220 				    struct trace_pid_list *no_pid_list)
221 {
222 	/* Return true if the pid list in type has pids */
223 	return ((type & TRACE_PIDS) && pid_list) ||
224 		((type & TRACE_NO_PIDS) && no_pid_list);
225 }
226 
still_need_pid_events(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)227 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
228 					 struct trace_pid_list *no_pid_list)
229 {
230 	/*
231 	 * Turning off what is in @type, return true if the "other"
232 	 * pid list, still has pids in it.
233 	 */
234 	return (!(type & TRACE_PIDS) && pid_list) ||
235 		(!(type & TRACE_NO_PIDS) && no_pid_list);
236 }
237 
238 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
239 
240 /**
241  * struct cond_snapshot - conditional snapshot data and callback
242  *
243  * The cond_snapshot structure encapsulates a callback function and
244  * data associated with the snapshot for a given tracing instance.
245  *
246  * When a snapshot is taken conditionally, by invoking
247  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
248  * passed in turn to the cond_snapshot.update() function.  That data
249  * can be compared by the update() implementation with the cond_data
250  * contained within the struct cond_snapshot instance associated with
251  * the trace_array.  Because the tr->max_lock is held throughout the
252  * update() call, the update() function can directly retrieve the
253  * cond_snapshot and cond_data associated with the per-instance
254  * snapshot associated with the trace_array.
255  *
256  * The cond_snapshot.update() implementation can save data to be
257  * associated with the snapshot if it decides to, and returns 'true'
258  * in that case, or it returns 'false' if the conditional snapshot
259  * shouldn't be taken.
260  *
261  * The cond_snapshot instance is created and associated with the
262  * user-defined cond_data by tracing_cond_snapshot_enable().
263  * Likewise, the cond_snapshot instance is destroyed and is no longer
264  * associated with the trace instance by
265  * tracing_cond_snapshot_disable().
266  *
267  * The method below is required.
268  *
269  * @update: When a conditional snapshot is invoked, the update()
270  *	callback function is invoked with the tr->max_lock held.  The
271  *	update() implementation signals whether or not to actually
272  *	take the snapshot, by returning 'true' if so, 'false' if no
273  *	snapshot should be taken.  Because the max_lock is held for
274  *	the duration of update(), the implementation is safe to
275  *	directly retrieved and save any implementation data it needs
276  *	to in association with the snapshot.
277  */
278 struct cond_snapshot {
279 	void				*cond_data;
280 	cond_update_fn_t		update;
281 };
282 
283 /*
284  * struct trace_func_repeats - used to keep track of the consecutive
285  * (on the same CPU) calls of a single function.
286  */
287 struct trace_func_repeats {
288 	unsigned long	ip;
289 	unsigned long	parent_ip;
290 	unsigned long	count;
291 	u64		ts_last_call;
292 };
293 
294 /*
295  * The trace array - an array of per-CPU trace arrays. This is the
296  * highest level data structure that individual tracers deal with.
297  * They have on/off state as well:
298  */
299 struct trace_array {
300 	struct list_head	list;
301 	char			*name;
302 	struct array_buffer	array_buffer;
303 #ifdef CONFIG_TRACER_MAX_TRACE
304 	/*
305 	 * The max_buffer is used to snapshot the trace when a maximum
306 	 * latency is reached, or when the user initiates a snapshot.
307 	 * Some tracers will use this to store a maximum trace while
308 	 * it continues examining live traces.
309 	 *
310 	 * The buffers for the max_buffer are set up the same as the array_buffer
311 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
312 	 * with the buffer of the array_buffer and the buffers are reset for
313 	 * the array_buffer so the tracing can continue.
314 	 */
315 	struct array_buffer	max_buffer;
316 	bool			allocated_snapshot;
317 #endif
318 #ifdef CONFIG_TRACER_MAX_TRACE
319 	unsigned long		max_latency;
320 #ifdef CONFIG_FSNOTIFY
321 	struct dentry		*d_max_latency;
322 	struct work_struct	fsnotify_work;
323 	struct irq_work		fsnotify_irqwork;
324 #endif
325 #endif
326 	struct trace_pid_list	__rcu *filtered_pids;
327 	struct trace_pid_list	__rcu *filtered_no_pids;
328 	/*
329 	 * max_lock is used to protect the swapping of buffers
330 	 * when taking a max snapshot. The buffers themselves are
331 	 * protected by per_cpu spinlocks. But the action of the swap
332 	 * needs its own lock.
333 	 *
334 	 * This is defined as a arch_spinlock_t in order to help
335 	 * with performance when lockdep debugging is enabled.
336 	 *
337 	 * It is also used in other places outside the update_max_tr
338 	 * so it needs to be defined outside of the
339 	 * CONFIG_TRACER_MAX_TRACE.
340 	 */
341 	arch_spinlock_t		max_lock;
342 	int			buffer_disabled;
343 #ifdef CONFIG_FTRACE_SYSCALLS
344 	int			sys_refcount_enter;
345 	int			sys_refcount_exit;
346 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
347 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
348 #endif
349 	int			stop_count;
350 	int			clock_id;
351 	int			nr_topts;
352 	bool			clear_trace;
353 	int			buffer_percent;
354 	unsigned int		n_err_log_entries;
355 	struct tracer		*current_trace;
356 	unsigned int		trace_flags;
357 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
358 	unsigned int		flags;
359 	raw_spinlock_t		start_lock;
360 	struct list_head	err_log;
361 	struct dentry		*dir;
362 	struct dentry		*options;
363 	struct dentry		*percpu_dir;
364 	struct dentry		*event_dir;
365 	struct trace_options	*topts;
366 	struct list_head	systems;
367 	struct list_head	events;
368 	struct trace_event_file *trace_marker_file;
369 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
370 	int			ref;
371 	int			trace_ref;
372 #ifdef CONFIG_FUNCTION_TRACER
373 	struct ftrace_ops	*ops;
374 	struct trace_pid_list	__rcu *function_pids;
375 	struct trace_pid_list	__rcu *function_no_pids;
376 #ifdef CONFIG_DYNAMIC_FTRACE
377 	/* All of these are protected by the ftrace_lock */
378 	struct list_head	func_probes;
379 	struct list_head	mod_trace;
380 	struct list_head	mod_notrace;
381 #endif
382 	/* function tracing enabled */
383 	int			function_enabled;
384 #endif
385 	int			no_filter_buffering_ref;
386 	struct list_head	hist_vars;
387 #ifdef CONFIG_TRACER_SNAPSHOT
388 	struct cond_snapshot	*cond_snapshot;
389 #endif
390 	struct trace_func_repeats	__percpu *last_func_repeats;
391 };
392 
393 enum {
394 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
395 };
396 
397 extern struct list_head ftrace_trace_arrays;
398 
399 extern struct mutex trace_types_lock;
400 
401 extern int trace_array_get(struct trace_array *tr);
402 extern int tracing_check_open_get_tr(struct trace_array *tr);
403 extern struct trace_array *trace_array_find(const char *instance);
404 extern struct trace_array *trace_array_find_get(const char *instance);
405 
406 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
407 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
408 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
409 
410 extern bool trace_clock_in_ns(struct trace_array *tr);
411 
412 /*
413  * The global tracer (top) should be the first trace array added,
414  * but we check the flag anyway.
415  */
top_trace_array(void)416 static inline struct trace_array *top_trace_array(void)
417 {
418 	struct trace_array *tr;
419 
420 	if (list_empty(&ftrace_trace_arrays))
421 		return NULL;
422 
423 	tr = list_entry(ftrace_trace_arrays.prev,
424 			typeof(*tr), list);
425 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
426 	return tr;
427 }
428 
429 #define FTRACE_CMP_TYPE(var, type) \
430 	__builtin_types_compatible_p(typeof(var), type *)
431 
432 #undef IF_ASSIGN
433 #define IF_ASSIGN(var, entry, etype, id)			\
434 	if (FTRACE_CMP_TYPE(var, etype)) {			\
435 		var = (typeof(var))(entry);			\
436 		WARN_ON(id != 0 && (entry)->type != id);	\
437 		break;						\
438 	}
439 
440 /* Will cause compile errors if type is not found. */
441 extern void __ftrace_bad_type(void);
442 
443 /*
444  * The trace_assign_type is a verifier that the entry type is
445  * the same as the type being assigned. To add new types simply
446  * add a line with the following format:
447  *
448  * IF_ASSIGN(var, ent, type, id);
449  *
450  *  Where "type" is the trace type that includes the trace_entry
451  *  as the "ent" item. And "id" is the trace identifier that is
452  *  used in the trace_type enum.
453  *
454  *  If the type can have more than one id, then use zero.
455  */
456 #define trace_assign_type(var, ent)					\
457 	do {								\
458 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
459 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
460 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
461 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
462 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
463 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
464 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
465 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
466 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
467 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
468 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
469 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
470 			  TRACE_MMIO_RW);				\
471 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
472 			  TRACE_MMIO_MAP);				\
473 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
474 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
475 			  TRACE_GRAPH_ENT);		\
476 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
477 			  TRACE_GRAPH_RET);		\
478 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
479 			  TRACE_FUNC_REPEATS);				\
480 		__ftrace_bad_type();					\
481 	} while (0)
482 
483 /*
484  * An option specific to a tracer. This is a boolean value.
485  * The bit is the bit index that sets its value on the
486  * flags value in struct tracer_flags.
487  */
488 struct tracer_opt {
489 	const char	*name; /* Will appear on the trace_options file */
490 	u32		bit; /* Mask assigned in val field in tracer_flags */
491 };
492 
493 /*
494  * The set of specific options for a tracer. Your tracer
495  * have to set the initial value of the flags val.
496  */
497 struct tracer_flags {
498 	u32			val;
499 	struct tracer_opt	*opts;
500 	struct tracer		*trace;
501 };
502 
503 /* Makes more easy to define a tracer opt */
504 #define TRACER_OPT(s, b)	.name = #s, .bit = b
505 
506 
507 struct trace_option_dentry {
508 	struct tracer_opt		*opt;
509 	struct tracer_flags		*flags;
510 	struct trace_array		*tr;
511 	struct dentry			*entry;
512 };
513 
514 /**
515  * struct tracer - a specific tracer and its callbacks to interact with tracefs
516  * @name: the name chosen to select it on the available_tracers file
517  * @init: called when one switches to this tracer (echo name > current_tracer)
518  * @reset: called when one switches to another tracer
519  * @start: called when tracing is unpaused (echo 1 > tracing_on)
520  * @stop: called when tracing is paused (echo 0 > tracing_on)
521  * @update_thresh: called when tracing_thresh is updated
522  * @open: called when the trace file is opened
523  * @pipe_open: called when the trace_pipe file is opened
524  * @close: called when the trace file is released
525  * @pipe_close: called when the trace_pipe file is released
526  * @read: override the default read callback on trace_pipe
527  * @splice_read: override the default splice_read callback on trace_pipe
528  * @selftest: selftest to run on boot (see trace_selftest.c)
529  * @print_headers: override the first lines that describe your columns
530  * @print_line: callback that prints a trace
531  * @set_flag: signals one of your private flags changed (trace_options file)
532  * @flags: your private flags
533  */
534 struct tracer {
535 	const char		*name;
536 	int			(*init)(struct trace_array *tr);
537 	void			(*reset)(struct trace_array *tr);
538 	void			(*start)(struct trace_array *tr);
539 	void			(*stop)(struct trace_array *tr);
540 	int			(*update_thresh)(struct trace_array *tr);
541 	void			(*open)(struct trace_iterator *iter);
542 	void			(*pipe_open)(struct trace_iterator *iter);
543 	void			(*close)(struct trace_iterator *iter);
544 	void			(*pipe_close)(struct trace_iterator *iter);
545 	ssize_t			(*read)(struct trace_iterator *iter,
546 					struct file *filp, char __user *ubuf,
547 					size_t cnt, loff_t *ppos);
548 	ssize_t			(*splice_read)(struct trace_iterator *iter,
549 					       struct file *filp,
550 					       loff_t *ppos,
551 					       struct pipe_inode_info *pipe,
552 					       size_t len,
553 					       unsigned int flags);
554 #ifdef CONFIG_FTRACE_STARTUP_TEST
555 	int			(*selftest)(struct tracer *trace,
556 					    struct trace_array *tr);
557 #endif
558 	void			(*print_header)(struct seq_file *m);
559 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
560 	/* If you handled the flag setting, return 0 */
561 	int			(*set_flag)(struct trace_array *tr,
562 					    u32 old_flags, u32 bit, int set);
563 	/* Return 0 if OK with change, else return non-zero */
564 	int			(*flag_changed)(struct trace_array *tr,
565 						u32 mask, int set);
566 	struct tracer		*next;
567 	struct tracer_flags	*flags;
568 	int			enabled;
569 	bool			print_max;
570 	bool			allow_instances;
571 #ifdef CONFIG_TRACER_MAX_TRACE
572 	bool			use_max_tr;
573 #endif
574 	/* True if tracer cannot be enabled in kernel param */
575 	bool			noboot;
576 };
577 
578 static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)579 trace_buffer_iter(struct trace_iterator *iter, int cpu)
580 {
581 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
582 }
583 
584 int tracer_init(struct tracer *t, struct trace_array *tr);
585 int tracing_is_enabled(void);
586 void tracing_reset_online_cpus(struct array_buffer *buf);
587 void tracing_reset_current(int cpu);
588 void tracing_reset_all_online_cpus(void);
589 void tracing_reset_all_online_cpus_unlocked(void);
590 int tracing_open_generic(struct inode *inode, struct file *filp);
591 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
592 int tracing_open_file_tr(struct inode *inode, struct file *filp);
593 int tracing_release_file_tr(struct inode *inode, struct file *filp);
594 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
595 bool tracing_is_disabled(void);
596 bool tracer_tracing_is_on(struct trace_array *tr);
597 void tracer_tracing_on(struct trace_array *tr);
598 void tracer_tracing_off(struct trace_array *tr);
599 struct dentry *trace_create_file(const char *name,
600 				 umode_t mode,
601 				 struct dentry *parent,
602 				 void *data,
603 				 const struct file_operations *fops);
604 
605 int tracing_init_dentry(void);
606 
607 struct ring_buffer_event;
608 
609 struct ring_buffer_event *
610 trace_buffer_lock_reserve(struct trace_buffer *buffer,
611 			  int type,
612 			  unsigned long len,
613 			  unsigned int trace_ctx);
614 
615 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
616 						struct trace_array_cpu *data);
617 
618 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
619 					  int *ent_cpu, u64 *ent_ts);
620 
621 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
622 					struct ring_buffer_event *event);
623 
624 bool trace_is_tracepoint_string(const char *str);
625 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
626 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
627 			 va_list ap);
628 
629 int trace_empty(struct trace_iterator *iter);
630 
631 void *trace_find_next_entry_inc(struct trace_iterator *iter);
632 
633 void trace_init_global_iter(struct trace_iterator *iter);
634 
635 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
636 
637 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
638 unsigned long trace_total_entries(struct trace_array *tr);
639 
640 void trace_function(struct trace_array *tr,
641 		    unsigned long ip,
642 		    unsigned long parent_ip,
643 		    unsigned int trace_ctx);
644 void trace_graph_function(struct trace_array *tr,
645 		    unsigned long ip,
646 		    unsigned long parent_ip,
647 		    unsigned int trace_ctx);
648 void trace_latency_header(struct seq_file *m);
649 void trace_default_header(struct seq_file *m);
650 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
651 
652 void trace_graph_return(struct ftrace_graph_ret *trace);
653 int trace_graph_entry(struct ftrace_graph_ent *trace);
654 void set_graph_array(struct trace_array *tr);
655 
656 void tracing_start_cmdline_record(void);
657 void tracing_stop_cmdline_record(void);
658 void tracing_start_tgid_record(void);
659 void tracing_stop_tgid_record(void);
660 
661 int register_tracer(struct tracer *type);
662 int is_tracing_stopped(void);
663 
664 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
665 
666 extern cpumask_var_t __read_mostly tracing_buffer_mask;
667 
668 #define for_each_tracing_cpu(cpu)	\
669 	for_each_cpu(cpu, tracing_buffer_mask)
670 
671 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
672 
673 extern unsigned long tracing_thresh;
674 
675 /* PID filtering */
676 
677 extern int pid_max;
678 
679 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
680 			     pid_t search_pid);
681 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
682 			    struct trace_pid_list *filtered_no_pids,
683 			    struct task_struct *task);
684 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
685 				  struct task_struct *self,
686 				  struct task_struct *task);
687 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
688 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
689 int trace_pid_show(struct seq_file *m, void *v);
690 void trace_free_pid_list(struct trace_pid_list *pid_list);
691 int trace_pid_write(struct trace_pid_list *filtered_pids,
692 		    struct trace_pid_list **new_pid_list,
693 		    const char __user *ubuf, size_t cnt);
694 
695 #ifdef CONFIG_TRACER_MAX_TRACE
696 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
697 		   void *cond_data);
698 void update_max_tr_single(struct trace_array *tr,
699 			  struct task_struct *tsk, int cpu);
700 
701 #ifdef CONFIG_FSNOTIFY
702 #define LATENCY_FS_NOTIFY
703 #endif
704 #endif /* CONFIG_TRACER_MAX_TRACE */
705 
706 #ifdef LATENCY_FS_NOTIFY
707 void latency_fsnotify(struct trace_array *tr);
708 #else
latency_fsnotify(struct trace_array * tr)709 static inline void latency_fsnotify(struct trace_array *tr) { }
710 #endif
711 
712 #ifdef CONFIG_STACKTRACE
713 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
714 #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)715 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
716 				 int skip)
717 {
718 }
719 #endif /* CONFIG_STACKTRACE */
720 
721 void trace_last_func_repeats(struct trace_array *tr,
722 			     struct trace_func_repeats *last_info,
723 			     unsigned int trace_ctx);
724 
725 extern u64 ftrace_now(int cpu);
726 
727 extern void trace_find_cmdline(int pid, char comm[]);
728 extern int trace_find_tgid(int pid);
729 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
730 
731 #ifdef CONFIG_DYNAMIC_FTRACE
732 extern unsigned long ftrace_update_tot_cnt;
733 extern unsigned long ftrace_number_of_pages;
734 extern unsigned long ftrace_number_of_groups;
735 void ftrace_init_trace_array(struct trace_array *tr);
736 #else
ftrace_init_trace_array(struct trace_array * tr)737 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
738 #endif
739 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
740 extern int DYN_FTRACE_TEST_NAME(void);
741 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
742 extern int DYN_FTRACE_TEST_NAME2(void);
743 
744 extern bool ring_buffer_expanded;
745 extern bool tracing_selftest_disabled;
746 
747 #ifdef CONFIG_FTRACE_STARTUP_TEST
748 extern void __init disable_tracing_selftest(const char *reason);
749 
750 extern int trace_selftest_startup_function(struct tracer *trace,
751 					   struct trace_array *tr);
752 extern int trace_selftest_startup_function_graph(struct tracer *trace,
753 						 struct trace_array *tr);
754 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
755 					  struct trace_array *tr);
756 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
757 					     struct trace_array *tr);
758 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
759 						 struct trace_array *tr);
760 extern int trace_selftest_startup_wakeup(struct tracer *trace,
761 					 struct trace_array *tr);
762 extern int trace_selftest_startup_nop(struct tracer *trace,
763 					 struct trace_array *tr);
764 extern int trace_selftest_startup_branch(struct tracer *trace,
765 					 struct trace_array *tr);
766 /*
767  * Tracer data references selftest functions that only occur
768  * on boot up. These can be __init functions. Thus, when selftests
769  * are enabled, then the tracers need to reference __init functions.
770  */
771 #define __tracer_data		__refdata
772 #else
disable_tracing_selftest(const char * reason)773 static inline void __init disable_tracing_selftest(const char *reason)
774 {
775 }
776 /* Tracers are seldom changed. Optimize when selftests are disabled. */
777 #define __tracer_data		__read_mostly
778 #endif /* CONFIG_FTRACE_STARTUP_TEST */
779 
780 extern void *head_page(struct trace_array_cpu *data);
781 extern unsigned long long ns2usecs(u64 nsec);
782 extern int
783 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
784 extern int
785 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
786 extern int
787 trace_array_vprintk(struct trace_array *tr,
788 		    unsigned long ip, const char *fmt, va_list args);
789 int trace_array_printk_buf(struct trace_buffer *buffer,
790 			   unsigned long ip, const char *fmt, ...);
791 void trace_printk_seq(struct trace_seq *s);
792 enum print_line_t print_trace_line(struct trace_iterator *iter);
793 
794 extern char trace_find_mark(unsigned long long duration);
795 
796 struct ftrace_hash;
797 
798 struct ftrace_mod_load {
799 	struct list_head	list;
800 	char			*func;
801 	char			*module;
802 	int			 enable;
803 };
804 
805 enum {
806 	FTRACE_HASH_FL_MOD	= (1 << 0),
807 };
808 
809 struct ftrace_hash {
810 	unsigned long		size_bits;
811 	struct hlist_head	*buckets;
812 	unsigned long		count;
813 	unsigned long		flags;
814 	struct rcu_head		rcu;
815 };
816 
817 struct ftrace_func_entry *
818 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
819 
ftrace_hash_empty(struct ftrace_hash * hash)820 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
821 {
822 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
823 }
824 
825 /* Standard output formatting function used for function return traces */
826 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
827 
828 /* Flag options */
829 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
830 #define TRACE_GRAPH_PRINT_CPU           0x2
831 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
832 #define TRACE_GRAPH_PRINT_PROC          0x8
833 #define TRACE_GRAPH_PRINT_DURATION      0x10
834 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
835 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
836 #define TRACE_GRAPH_PRINT_IRQS          0x80
837 #define TRACE_GRAPH_PRINT_TAIL          0x100
838 #define TRACE_GRAPH_SLEEP_TIME          0x200
839 #define TRACE_GRAPH_GRAPH_TIME          0x400
840 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
841 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
842 
843 extern void ftrace_graph_sleep_time_control(bool enable);
844 
845 #ifdef CONFIG_FUNCTION_PROFILER
846 extern void ftrace_graph_graph_time_control(bool enable);
847 #else
ftrace_graph_graph_time_control(bool enable)848 static inline void ftrace_graph_graph_time_control(bool enable) { }
849 #endif
850 
851 extern enum print_line_t
852 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
853 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
854 extern void
855 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
856 extern void graph_trace_open(struct trace_iterator *iter);
857 extern void graph_trace_close(struct trace_iterator *iter);
858 extern int __trace_graph_entry(struct trace_array *tr,
859 			       struct ftrace_graph_ent *trace,
860 			       unsigned int trace_ctx);
861 extern void __trace_graph_return(struct trace_array *tr,
862 				 struct ftrace_graph_ret *trace,
863 				 unsigned int trace_ctx);
864 
865 #ifdef CONFIG_DYNAMIC_FTRACE
866 extern struct ftrace_hash __rcu *ftrace_graph_hash;
867 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
868 
ftrace_graph_addr(struct ftrace_graph_ent * trace)869 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
870 {
871 	unsigned long addr = trace->func;
872 	int ret = 0;
873 	struct ftrace_hash *hash;
874 
875 	preempt_disable_notrace();
876 
877 	/*
878 	 * Have to open code "rcu_dereference_sched()" because the
879 	 * function graph tracer can be called when RCU is not
880 	 * "watching".
881 	 * Protected with schedule_on_each_cpu(ftrace_sync)
882 	 */
883 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
884 
885 	if (ftrace_hash_empty(hash)) {
886 		ret = 1;
887 		goto out;
888 	}
889 
890 	if (ftrace_lookup_ip(hash, addr)) {
891 
892 		/*
893 		 * This needs to be cleared on the return functions
894 		 * when the depth is zero.
895 		 */
896 		trace_recursion_set(TRACE_GRAPH_BIT);
897 		trace_recursion_set_depth(trace->depth);
898 
899 		/*
900 		 * If no irqs are to be traced, but a set_graph_function
901 		 * is set, and called by an interrupt handler, we still
902 		 * want to trace it.
903 		 */
904 		if (in_irq())
905 			trace_recursion_set(TRACE_IRQ_BIT);
906 		else
907 			trace_recursion_clear(TRACE_IRQ_BIT);
908 		ret = 1;
909 	}
910 
911 out:
912 	preempt_enable_notrace();
913 	return ret;
914 }
915 
ftrace_graph_addr_finish(struct ftrace_graph_ret * trace)916 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
917 {
918 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
919 	    trace->depth == trace_recursion_depth())
920 		trace_recursion_clear(TRACE_GRAPH_BIT);
921 }
922 
ftrace_graph_notrace_addr(unsigned long addr)923 static inline int ftrace_graph_notrace_addr(unsigned long addr)
924 {
925 	int ret = 0;
926 	struct ftrace_hash *notrace_hash;
927 
928 	preempt_disable_notrace();
929 
930 	/*
931 	 * Have to open code "rcu_dereference_sched()" because the
932 	 * function graph tracer can be called when RCU is not
933 	 * "watching".
934 	 * Protected with schedule_on_each_cpu(ftrace_sync)
935 	 */
936 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
937 						 !preemptible());
938 
939 	if (ftrace_lookup_ip(notrace_hash, addr))
940 		ret = 1;
941 
942 	preempt_enable_notrace();
943 	return ret;
944 }
945 #else
ftrace_graph_addr(struct ftrace_graph_ent * trace)946 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
947 {
948 	return 1;
949 }
950 
ftrace_graph_notrace_addr(unsigned long addr)951 static inline int ftrace_graph_notrace_addr(unsigned long addr)
952 {
953 	return 0;
954 }
ftrace_graph_addr_finish(struct ftrace_graph_ret * trace)955 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
956 { }
957 #endif /* CONFIG_DYNAMIC_FTRACE */
958 
959 extern unsigned int fgraph_max_depth;
960 
ftrace_graph_ignore_func(struct ftrace_graph_ent * trace)961 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
962 {
963 	/* trace it when it is-nested-in or is a function enabled. */
964 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
965 		 ftrace_graph_addr(trace)) ||
966 		(trace->depth < 0) ||
967 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
968 }
969 
970 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
971 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)972 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
973 {
974 	return TRACE_TYPE_UNHANDLED;
975 }
976 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
977 
978 extern struct list_head ftrace_pids;
979 
980 #ifdef CONFIG_FUNCTION_TRACER
981 
982 #define FTRACE_PID_IGNORE	-1
983 #define FTRACE_PID_TRACE	-2
984 
985 struct ftrace_func_command {
986 	struct list_head	list;
987 	char			*name;
988 	int			(*func)(struct trace_array *tr,
989 					struct ftrace_hash *hash,
990 					char *func, char *cmd,
991 					char *params, int enable);
992 };
993 extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)994 static inline int ftrace_trace_task(struct trace_array *tr)
995 {
996 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
997 		FTRACE_PID_IGNORE;
998 }
999 extern int ftrace_is_dead(void);
1000 int ftrace_create_function_files(struct trace_array *tr,
1001 				 struct dentry *parent);
1002 void ftrace_destroy_function_files(struct trace_array *tr);
1003 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1004 void ftrace_free_ftrace_ops(struct trace_array *tr);
1005 void ftrace_init_global_array_ops(struct trace_array *tr);
1006 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1007 void ftrace_reset_array_ops(struct trace_array *tr);
1008 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1009 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1010 				  struct dentry *d_tracer);
1011 void ftrace_clear_pids(struct trace_array *tr);
1012 int init_function_trace(void);
1013 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1014 #else
ftrace_trace_task(struct trace_array * tr)1015 static inline int ftrace_trace_task(struct trace_array *tr)
1016 {
1017 	return 1;
1018 }
ftrace_is_dead(void)1019 static inline int ftrace_is_dead(void) { return 0; }
1020 static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1021 ftrace_create_function_files(struct trace_array *tr,
1022 			     struct dentry *parent)
1023 {
1024 	return 0;
1025 }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1026 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1027 {
1028 	return 0;
1029 }
ftrace_free_ftrace_ops(struct trace_array * tr)1030 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1031 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1032 static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1033 ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1034 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1035 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1036 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1037 static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1038 static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1039 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1040 /* ftace_func_t type is not defined, use macro instead of static inline */
1041 #define ftrace_init_array_ops(tr, func) do { } while (0)
1042 #endif /* CONFIG_FUNCTION_TRACER */
1043 
1044 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1045 
1046 struct ftrace_probe_ops {
1047 	void			(*func)(unsigned long ip,
1048 					unsigned long parent_ip,
1049 					struct trace_array *tr,
1050 					struct ftrace_probe_ops *ops,
1051 					void *data);
1052 	int			(*init)(struct ftrace_probe_ops *ops,
1053 					struct trace_array *tr,
1054 					unsigned long ip, void *init_data,
1055 					void **data);
1056 	void			(*free)(struct ftrace_probe_ops *ops,
1057 					struct trace_array *tr,
1058 					unsigned long ip, void *data);
1059 	int			(*print)(struct seq_file *m,
1060 					 unsigned long ip,
1061 					 struct ftrace_probe_ops *ops,
1062 					 void *data);
1063 };
1064 
1065 struct ftrace_func_mapper;
1066 typedef int (*ftrace_mapper_func)(void *data);
1067 
1068 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1069 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1070 					   unsigned long ip);
1071 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1072 			       unsigned long ip, void *data);
1073 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1074 				   unsigned long ip);
1075 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1076 			     ftrace_mapper_func free_func);
1077 
1078 extern int
1079 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1080 			       struct ftrace_probe_ops *ops, void *data);
1081 extern int
1082 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1083 				      struct ftrace_probe_ops *ops);
1084 extern void clear_ftrace_function_probes(struct trace_array *tr);
1085 
1086 int register_ftrace_command(struct ftrace_func_command *cmd);
1087 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1088 
1089 void ftrace_create_filter_files(struct ftrace_ops *ops,
1090 				struct dentry *parent);
1091 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1092 
1093 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1094 			     int len, int reset);
1095 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1096 			      int len, int reset);
1097 #else
1098 struct ftrace_func_command;
1099 
register_ftrace_command(struct ftrace_func_command * cmd)1100 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1101 {
1102 	return -EINVAL;
1103 }
unregister_ftrace_command(char * cmd_name)1104 static inline __init int unregister_ftrace_command(char *cmd_name)
1105 {
1106 	return -EINVAL;
1107 }
clear_ftrace_function_probes(struct trace_array * tr)1108 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1109 {
1110 }
1111 
1112 /*
1113  * The ops parameter passed in is usually undefined.
1114  * This must be a macro.
1115  */
1116 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1117 #define ftrace_destroy_filter_files(ops) do { } while (0)
1118 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1119 
1120 bool ftrace_event_is_function(struct trace_event_call *call);
1121 
1122 /*
1123  * struct trace_parser - servers for reading the user input separated by spaces
1124  * @cont: set if the input is not complete - no final space char was found
1125  * @buffer: holds the parsed user input
1126  * @idx: user input length
1127  * @size: buffer size
1128  */
1129 struct trace_parser {
1130 	bool		cont;
1131 	char		*buffer;
1132 	unsigned	idx;
1133 	unsigned	size;
1134 };
1135 
trace_parser_loaded(struct trace_parser * parser)1136 static inline bool trace_parser_loaded(struct trace_parser *parser)
1137 {
1138 	return (parser->idx != 0);
1139 }
1140 
trace_parser_cont(struct trace_parser * parser)1141 static inline bool trace_parser_cont(struct trace_parser *parser)
1142 {
1143 	return parser->cont;
1144 }
1145 
trace_parser_clear(struct trace_parser * parser)1146 static inline void trace_parser_clear(struct trace_parser *parser)
1147 {
1148 	parser->cont = false;
1149 	parser->idx = 0;
1150 }
1151 
1152 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1153 extern void trace_parser_put(struct trace_parser *parser);
1154 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1155 	size_t cnt, loff_t *ppos);
1156 
1157 /*
1158  * Only create function graph options if function graph is configured.
1159  */
1160 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1161 # define FGRAPH_FLAGS						\
1162 		C(DISPLAY_GRAPH,	"display-graph"),
1163 #else
1164 # define FGRAPH_FLAGS
1165 #endif
1166 
1167 #ifdef CONFIG_BRANCH_TRACER
1168 # define BRANCH_FLAGS					\
1169 		C(BRANCH,		"branch"),
1170 #else
1171 # define BRANCH_FLAGS
1172 #endif
1173 
1174 #ifdef CONFIG_FUNCTION_TRACER
1175 # define FUNCTION_FLAGS						\
1176 		C(FUNCTION,		"function-trace"),	\
1177 		C(FUNC_FORK,		"function-fork"),
1178 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1179 #else
1180 # define FUNCTION_FLAGS
1181 # define FUNCTION_DEFAULT_FLAGS		0UL
1182 # define TRACE_ITER_FUNC_FORK		0UL
1183 #endif
1184 
1185 #ifdef CONFIG_STACKTRACE
1186 # define STACK_FLAGS				\
1187 		C(STACKTRACE,		"stacktrace"),
1188 #else
1189 # define STACK_FLAGS
1190 #endif
1191 
1192 /*
1193  * trace_iterator_flags is an enumeration that defines bit
1194  * positions into trace_flags that controls the output.
1195  *
1196  * NOTE: These bits must match the trace_options array in
1197  *       trace.c (this macro guarantees it).
1198  */
1199 #define TRACE_FLAGS						\
1200 		C(PRINT_PARENT,		"print-parent"),	\
1201 		C(SYM_OFFSET,		"sym-offset"),		\
1202 		C(SYM_ADDR,		"sym-addr"),		\
1203 		C(VERBOSE,		"verbose"),		\
1204 		C(RAW,			"raw"),			\
1205 		C(HEX,			"hex"),			\
1206 		C(BIN,			"bin"),			\
1207 		C(BLOCK,		"block"),		\
1208 		C(PRINTK,		"trace_printk"),	\
1209 		C(ANNOTATE,		"annotate"),		\
1210 		C(USERSTACKTRACE,	"userstacktrace"),	\
1211 		C(SYM_USEROBJ,		"sym-userobj"),		\
1212 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1213 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1214 		C(LATENCY_FMT,		"latency-format"),	\
1215 		C(RECORD_CMD,		"record-cmd"),		\
1216 		C(RECORD_TGID,		"record-tgid"),		\
1217 		C(OVERWRITE,		"overwrite"),		\
1218 		C(STOP_ON_FREE,		"disable_on_free"),	\
1219 		C(IRQ_INFO,		"irq-info"),		\
1220 		C(MARKERS,		"markers"),		\
1221 		C(EVENT_FORK,		"event-fork"),		\
1222 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1223 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1224 		FUNCTION_FLAGS					\
1225 		FGRAPH_FLAGS					\
1226 		STACK_FLAGS					\
1227 		BRANCH_FLAGS
1228 
1229 /*
1230  * By defining C, we can make TRACE_FLAGS a list of bit names
1231  * that will define the bits for the flag masks.
1232  */
1233 #undef C
1234 #define C(a, b) TRACE_ITER_##a##_BIT
1235 
1236 enum trace_iterator_bits {
1237 	TRACE_FLAGS
1238 	/* Make sure we don't go more than we have bits for */
1239 	TRACE_ITER_LAST_BIT
1240 };
1241 
1242 /*
1243  * By redefining C, we can make TRACE_FLAGS a list of masks that
1244  * use the bits as defined above.
1245  */
1246 #undef C
1247 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1248 
1249 enum trace_iterator_flags { TRACE_FLAGS };
1250 
1251 /*
1252  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1253  * control the output of kernel symbols.
1254  */
1255 #define TRACE_ITER_SYM_MASK \
1256 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1257 
1258 extern struct tracer nop_trace;
1259 
1260 #ifdef CONFIG_BRANCH_TRACER
1261 extern int enable_branch_tracing(struct trace_array *tr);
1262 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1263 static inline int trace_branch_enable(struct trace_array *tr)
1264 {
1265 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1266 		return enable_branch_tracing(tr);
1267 	return 0;
1268 }
trace_branch_disable(void)1269 static inline void trace_branch_disable(void)
1270 {
1271 	/* due to races, always disable */
1272 	disable_branch_tracing();
1273 }
1274 #else
trace_branch_enable(struct trace_array * tr)1275 static inline int trace_branch_enable(struct trace_array *tr)
1276 {
1277 	return 0;
1278 }
trace_branch_disable(void)1279 static inline void trace_branch_disable(void)
1280 {
1281 }
1282 #endif /* CONFIG_BRANCH_TRACER */
1283 
1284 /* set ring buffers to default size if not already done so */
1285 int tracing_update_buffers(void);
1286 
1287 struct ftrace_event_field {
1288 	struct list_head	link;
1289 	const char		*name;
1290 	const char		*type;
1291 	int			filter_type;
1292 	int			offset;
1293 	int			size;
1294 	int			is_signed;
1295 };
1296 
1297 struct prog_entry;
1298 
1299 struct event_filter {
1300 	struct prog_entry __rcu	*prog;
1301 	char			*filter_string;
1302 };
1303 
1304 struct event_subsystem {
1305 	struct list_head	list;
1306 	const char		*name;
1307 	struct event_filter	*filter;
1308 	int			ref_count;
1309 };
1310 
1311 struct trace_subsystem_dir {
1312 	struct list_head		list;
1313 	struct event_subsystem		*subsystem;
1314 	struct trace_array		*tr;
1315 	struct dentry			*entry;
1316 	int				ref_count;
1317 	int				nr_events;
1318 };
1319 
1320 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1321 				     struct trace_buffer *buffer,
1322 				     struct ring_buffer_event *event);
1323 
1324 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1325 				     struct trace_buffer *buffer,
1326 				     struct ring_buffer_event *event,
1327 				     unsigned int trcace_ctx,
1328 				     struct pt_regs *regs);
1329 
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1330 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1331 					      struct trace_buffer *buffer,
1332 					      struct ring_buffer_event *event,
1333 					      unsigned int trace_ctx)
1334 {
1335 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1336 }
1337 
1338 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1339 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1340 void trace_buffered_event_disable(void);
1341 void trace_buffered_event_enable(void);
1342 
1343 static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1344 __trace_event_discard_commit(struct trace_buffer *buffer,
1345 			     struct ring_buffer_event *event)
1346 {
1347 	if (this_cpu_read(trace_buffered_event) == event) {
1348 		/* Simply release the temp buffer */
1349 		this_cpu_dec(trace_buffered_event_cnt);
1350 		return;
1351 	}
1352 	ring_buffer_discard_commit(buffer, event);
1353 }
1354 
1355 /*
1356  * Helper function for event_trigger_unlock_commit{_regs}().
1357  * If there are event triggers attached to this event that requires
1358  * filtering against its fields, then they will be called as the
1359  * entry already holds the field information of the current event.
1360  *
1361  * It also checks if the event should be discarded or not.
1362  * It is to be discarded if the event is soft disabled and the
1363  * event was only recorded to process triggers, or if the event
1364  * filter is active and this event did not match the filters.
1365  *
1366  * Returns true if the event is discarded, false otherwise.
1367  */
1368 static inline bool
__event_trigger_test_discard(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,enum event_trigger_type * tt)1369 __event_trigger_test_discard(struct trace_event_file *file,
1370 			     struct trace_buffer *buffer,
1371 			     struct ring_buffer_event *event,
1372 			     void *entry,
1373 			     enum event_trigger_type *tt)
1374 {
1375 	unsigned long eflags = file->flags;
1376 
1377 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1378 		*tt = event_triggers_call(file, buffer, entry, event);
1379 
1380 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1381 				    EVENT_FILE_FL_FILTERED |
1382 				    EVENT_FILE_FL_PID_FILTER))))
1383 		return false;
1384 
1385 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1386 		goto discard;
1387 
1388 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1389 	    !filter_match_preds(file->filter, entry))
1390 		goto discard;
1391 
1392 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1393 	    trace_event_ignore_this_pid(file))
1394 		goto discard;
1395 
1396 	return false;
1397  discard:
1398 	__trace_event_discard_commit(buffer, event);
1399 	return true;
1400 }
1401 
1402 /**
1403  * event_trigger_unlock_commit - handle triggers and finish event commit
1404  * @file: The file pointer associated with the event
1405  * @buffer: The ring buffer that the event is being written to
1406  * @event: The event meta data in the ring buffer
1407  * @entry: The event itself
1408  * @trace_ctx: The tracing context flags.
1409  *
1410  * This is a helper function to handle triggers that require data
1411  * from the event itself. It also tests the event against filters and
1412  * if the event is soft disabled and should be discarded.
1413  */
1414 static inline void
event_trigger_unlock_commit(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,unsigned int trace_ctx)1415 event_trigger_unlock_commit(struct trace_event_file *file,
1416 			    struct trace_buffer *buffer,
1417 			    struct ring_buffer_event *event,
1418 			    void *entry, unsigned int trace_ctx)
1419 {
1420 	enum event_trigger_type tt = ETT_NONE;
1421 
1422 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1423 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1424 
1425 	if (tt)
1426 		event_triggers_post_call(file, tt);
1427 }
1428 
1429 #define FILTER_PRED_INVALID	((unsigned short)-1)
1430 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1431 #define FILTER_PRED_FOLD	(1 << 15)
1432 
1433 /*
1434  * The max preds is the size of unsigned short with
1435  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1436  * and FOLD flags. The other is reserved.
1437  *
1438  * 2^14 preds is way more than enough.
1439  */
1440 #define MAX_FILTER_PRED		16384
1441 
1442 struct filter_pred;
1443 struct regex;
1444 
1445 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1446 
1447 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1448 
1449 enum regex_type {
1450 	MATCH_FULL = 0,
1451 	MATCH_FRONT_ONLY,
1452 	MATCH_MIDDLE_ONLY,
1453 	MATCH_END_ONLY,
1454 	MATCH_GLOB,
1455 	MATCH_INDEX,
1456 };
1457 
1458 struct regex {
1459 	char			pattern[MAX_FILTER_STR_VAL];
1460 	int			len;
1461 	int			field_len;
1462 	regex_match_func	match;
1463 };
1464 
1465 struct filter_pred {
1466 	filter_pred_fn_t 	fn;
1467 	u64 			val;
1468 	struct regex		regex;
1469 	unsigned short		*ops;
1470 	struct ftrace_event_field *field;
1471 	int 			offset;
1472 	int			not;
1473 	int 			op;
1474 };
1475 
is_string_field(struct ftrace_event_field * field)1476 static inline bool is_string_field(struct ftrace_event_field *field)
1477 {
1478 	return field->filter_type == FILTER_DYN_STRING ||
1479 	       field->filter_type == FILTER_STATIC_STRING ||
1480 	       field->filter_type == FILTER_PTR_STRING ||
1481 	       field->filter_type == FILTER_COMM;
1482 }
1483 
is_function_field(struct ftrace_event_field * field)1484 static inline bool is_function_field(struct ftrace_event_field *field)
1485 {
1486 	return field->filter_type == FILTER_TRACE_FN;
1487 }
1488 
1489 extern enum regex_type
1490 filter_parse_regex(char *buff, int len, char **search, int *not);
1491 extern void print_event_filter(struct trace_event_file *file,
1492 			       struct trace_seq *s);
1493 extern int apply_event_filter(struct trace_event_file *file,
1494 			      char *filter_string);
1495 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1496 					char *filter_string);
1497 extern void print_subsystem_event_filter(struct event_subsystem *system,
1498 					 struct trace_seq *s);
1499 extern int filter_assign_type(const char *type);
1500 extern int create_event_filter(struct trace_array *tr,
1501 			       struct trace_event_call *call,
1502 			       char *filter_str, bool set_str,
1503 			       struct event_filter **filterp);
1504 extern void free_event_filter(struct event_filter *filter);
1505 
1506 struct ftrace_event_field *
1507 trace_find_event_field(struct trace_event_call *call, char *name);
1508 
1509 extern void trace_event_enable_cmd_record(bool enable);
1510 extern void trace_event_enable_tgid_record(bool enable);
1511 
1512 extern int event_trace_init(void);
1513 extern int init_events(void);
1514 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1515 extern int event_trace_del_tracer(struct trace_array *tr);
1516 extern void __trace_early_add_events(struct trace_array *tr);
1517 
1518 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1519 						  const char *system,
1520 						  const char *event);
1521 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1522 						const char *system,
1523 						const char *event);
1524 
event_file_data(struct file * filp)1525 static inline void *event_file_data(struct file *filp)
1526 {
1527 	return READ_ONCE(file_inode(filp)->i_private);
1528 }
1529 
1530 extern struct mutex event_mutex;
1531 extern struct list_head ftrace_events;
1532 
1533 extern const struct file_operations event_trigger_fops;
1534 extern const struct file_operations event_hist_fops;
1535 extern const struct file_operations event_hist_debug_fops;
1536 extern const struct file_operations event_inject_fops;
1537 
1538 #ifdef CONFIG_HIST_TRIGGERS
1539 extern int register_trigger_hist_cmd(void);
1540 extern int register_trigger_hist_enable_disable_cmds(void);
1541 #else
register_trigger_hist_cmd(void)1542 static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1543 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1544 #endif
1545 
1546 extern int register_trigger_cmds(void);
1547 extern void clear_event_triggers(struct trace_array *tr);
1548 
1549 enum {
1550 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1551 };
1552 
1553 struct event_trigger_data {
1554 	unsigned long			count;
1555 	int				ref;
1556 	int				flags;
1557 	struct event_trigger_ops	*ops;
1558 	struct event_command		*cmd_ops;
1559 	struct event_filter __rcu	*filter;
1560 	char				*filter_str;
1561 	void				*private_data;
1562 	bool				paused;
1563 	bool				paused_tmp;
1564 	struct list_head		list;
1565 	char				*name;
1566 	struct list_head		named_list;
1567 	struct event_trigger_data	*named_data;
1568 };
1569 
1570 /* Avoid typos */
1571 #define ENABLE_EVENT_STR	"enable_event"
1572 #define DISABLE_EVENT_STR	"disable_event"
1573 #define ENABLE_HIST_STR		"enable_hist"
1574 #define DISABLE_HIST_STR	"disable_hist"
1575 
1576 struct enable_trigger_data {
1577 	struct trace_event_file		*file;
1578 	bool				enable;
1579 	bool				hist;
1580 };
1581 
1582 extern int event_enable_trigger_print(struct seq_file *m,
1583 				      struct event_trigger_ops *ops,
1584 				      struct event_trigger_data *data);
1585 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1586 				      struct event_trigger_data *data);
1587 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1588 				     struct trace_event_file *file,
1589 				     char *glob, char *cmd, char *param);
1590 extern int event_enable_register_trigger(char *glob,
1591 					 struct event_trigger_ops *ops,
1592 					 struct event_trigger_data *data,
1593 					 struct trace_event_file *file);
1594 extern void event_enable_unregister_trigger(char *glob,
1595 					    struct event_trigger_ops *ops,
1596 					    struct event_trigger_data *test,
1597 					    struct trace_event_file *file);
1598 extern void trigger_data_free(struct event_trigger_data *data);
1599 extern int event_trigger_init(struct event_trigger_ops *ops,
1600 			      struct event_trigger_data *data);
1601 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1602 					      int trigger_enable);
1603 extern void update_cond_flag(struct trace_event_file *file);
1604 extern int set_trigger_filter(char *filter_str,
1605 			      struct event_trigger_data *trigger_data,
1606 			      struct trace_event_file *file);
1607 extern struct event_trigger_data *find_named_trigger(const char *name);
1608 extern bool is_named_trigger(struct event_trigger_data *test);
1609 extern int save_named_trigger(const char *name,
1610 			      struct event_trigger_data *data);
1611 extern void del_named_trigger(struct event_trigger_data *data);
1612 extern void pause_named_trigger(struct event_trigger_data *data);
1613 extern void unpause_named_trigger(struct event_trigger_data *data);
1614 extern void set_named_trigger_data(struct event_trigger_data *data,
1615 				   struct event_trigger_data *named_data);
1616 extern struct event_trigger_data *
1617 get_named_trigger_data(struct event_trigger_data *data);
1618 extern int register_event_command(struct event_command *cmd);
1619 extern int unregister_event_command(struct event_command *cmd);
1620 extern int register_trigger_hist_enable_disable_cmds(void);
1621 
1622 /**
1623  * struct event_trigger_ops - callbacks for trace event triggers
1624  *
1625  * The methods in this structure provide per-event trigger hooks for
1626  * various trigger operations.
1627  *
1628  * All the methods below, except for @init() and @free(), must be
1629  * implemented.
1630  *
1631  * @func: The trigger 'probe' function called when the triggering
1632  *	event occurs.  The data passed into this callback is the data
1633  *	that was supplied to the event_command @reg() function that
1634  *	registered the trigger (see struct event_command) along with
1635  *	the trace record, rec.
1636  *
1637  * @init: An optional initialization function called for the trigger
1638  *	when the trigger is registered (via the event_command reg()
1639  *	function).  This can be used to perform per-trigger
1640  *	initialization such as incrementing a per-trigger reference
1641  *	count, for instance.  This is usually implemented by the
1642  *	generic utility function @event_trigger_init() (see
1643  *	trace_event_triggers.c).
1644  *
1645  * @free: An optional de-initialization function called for the
1646  *	trigger when the trigger is unregistered (via the
1647  *	event_command @reg() function).  This can be used to perform
1648  *	per-trigger de-initialization such as decrementing a
1649  *	per-trigger reference count and freeing corresponding trigger
1650  *	data, for instance.  This is usually implemented by the
1651  *	generic utility function @event_trigger_free() (see
1652  *	trace_event_triggers.c).
1653  *
1654  * @print: The callback function invoked to have the trigger print
1655  *	itself.  This is usually implemented by a wrapper function
1656  *	that calls the generic utility function @event_trigger_print()
1657  *	(see trace_event_triggers.c).
1658  */
1659 struct event_trigger_ops {
1660 	void			(*func)(struct event_trigger_data *data,
1661 					struct trace_buffer *buffer, void *rec,
1662 					struct ring_buffer_event *rbe);
1663 	int			(*init)(struct event_trigger_ops *ops,
1664 					struct event_trigger_data *data);
1665 	void			(*free)(struct event_trigger_ops *ops,
1666 					struct event_trigger_data *data);
1667 	int			(*print)(struct seq_file *m,
1668 					 struct event_trigger_ops *ops,
1669 					 struct event_trigger_data *data);
1670 };
1671 
1672 /**
1673  * struct event_command - callbacks and data members for event commands
1674  *
1675  * Event commands are invoked by users by writing the command name
1676  * into the 'trigger' file associated with a trace event.  The
1677  * parameters associated with a specific invocation of an event
1678  * command are used to create an event trigger instance, which is
1679  * added to the list of trigger instances associated with that trace
1680  * event.  When the event is hit, the set of triggers associated with
1681  * that event is invoked.
1682  *
1683  * The data members in this structure provide per-event command data
1684  * for various event commands.
1685  *
1686  * All the data members below, except for @post_trigger, must be set
1687  * for each event command.
1688  *
1689  * @name: The unique name that identifies the event command.  This is
1690  *	the name used when setting triggers via trigger files.
1691  *
1692  * @trigger_type: A unique id that identifies the event command
1693  *	'type'.  This value has two purposes, the first to ensure that
1694  *	only one trigger of the same type can be set at a given time
1695  *	for a particular event e.g. it doesn't make sense to have both
1696  *	a traceon and traceoff trigger attached to a single event at
1697  *	the same time, so traceon and traceoff have the same type
1698  *	though they have different names.  The @trigger_type value is
1699  *	also used as a bit value for deferring the actual trigger
1700  *	action until after the current event is finished.  Some
1701  *	commands need to do this if they themselves log to the trace
1702  *	buffer (see the @post_trigger() member below).  @trigger_type
1703  *	values are defined by adding new values to the trigger_type
1704  *	enum in include/linux/trace_events.h.
1705  *
1706  * @flags: See the enum event_command_flags below.
1707  *
1708  * All the methods below, except for @set_filter() and @unreg_all(),
1709  * must be implemented.
1710  *
1711  * @func: The callback function responsible for parsing and
1712  *	registering the trigger written to the 'trigger' file by the
1713  *	user.  It allocates the trigger instance and registers it with
1714  *	the appropriate trace event.  It makes use of the other
1715  *	event_command callback functions to orchestrate this, and is
1716  *	usually implemented by the generic utility function
1717  *	@event_trigger_callback() (see trace_event_triggers.c).
1718  *
1719  * @reg: Adds the trigger to the list of triggers associated with the
1720  *	event, and enables the event trigger itself, after
1721  *	initializing it (via the event_trigger_ops @init() function).
1722  *	This is also where commands can use the @trigger_type value to
1723  *	make the decision as to whether or not multiple instances of
1724  *	the trigger should be allowed.  This is usually implemented by
1725  *	the generic utility function @register_trigger() (see
1726  *	trace_event_triggers.c).
1727  *
1728  * @unreg: Removes the trigger from the list of triggers associated
1729  *	with the event, and disables the event trigger itself, after
1730  *	initializing it (via the event_trigger_ops @free() function).
1731  *	This is usually implemented by the generic utility function
1732  *	@unregister_trigger() (see trace_event_triggers.c).
1733  *
1734  * @unreg_all: An optional function called to remove all the triggers
1735  *	from the list of triggers associated with the event.  Called
1736  *	when a trigger file is opened in truncate mode.
1737  *
1738  * @set_filter: An optional function called to parse and set a filter
1739  *	for the trigger.  If no @set_filter() method is set for the
1740  *	event command, filters set by the user for the command will be
1741  *	ignored.  This is usually implemented by the generic utility
1742  *	function @set_trigger_filter() (see trace_event_triggers.c).
1743  *
1744  * @get_trigger_ops: The callback function invoked to retrieve the
1745  *	event_trigger_ops implementation associated with the command.
1746  */
1747 struct event_command {
1748 	struct list_head	list;
1749 	char			*name;
1750 	enum event_trigger_type	trigger_type;
1751 	int			flags;
1752 	int			(*func)(struct event_command *cmd_ops,
1753 					struct trace_event_file *file,
1754 					char *glob, char *cmd, char *params);
1755 	int			(*reg)(char *glob,
1756 				       struct event_trigger_ops *ops,
1757 				       struct event_trigger_data *data,
1758 				       struct trace_event_file *file);
1759 	void			(*unreg)(char *glob,
1760 					 struct event_trigger_ops *ops,
1761 					 struct event_trigger_data *data,
1762 					 struct trace_event_file *file);
1763 	void			(*unreg_all)(struct trace_event_file *file);
1764 	int			(*set_filter)(char *filter_str,
1765 					      struct event_trigger_data *data,
1766 					      struct trace_event_file *file);
1767 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1768 };
1769 
1770 /**
1771  * enum event_command_flags - flags for struct event_command
1772  *
1773  * @POST_TRIGGER: A flag that says whether or not this command needs
1774  *	to have its action delayed until after the current event has
1775  *	been closed.  Some triggers need to avoid being invoked while
1776  *	an event is currently in the process of being logged, since
1777  *	the trigger may itself log data into the trace buffer.  Thus
1778  *	we make sure the current event is committed before invoking
1779  *	those triggers.  To do that, the trigger invocation is split
1780  *	in two - the first part checks the filter using the current
1781  *	trace record; if a command has the @post_trigger flag set, it
1782  *	sets a bit for itself in the return value, otherwise it
1783  *	directly invokes the trigger.  Once all commands have been
1784  *	either invoked or set their return flag, the current record is
1785  *	either committed or discarded.  At that point, if any commands
1786  *	have deferred their triggers, those commands are finally
1787  *	invoked following the close of the current event.  In other
1788  *	words, if the event_trigger_ops @func() probe implementation
1789  *	itself logs to the trace buffer, this flag should be set,
1790  *	otherwise it can be left unspecified.
1791  *
1792  * @NEEDS_REC: A flag that says whether or not this command needs
1793  *	access to the trace record in order to perform its function,
1794  *	regardless of whether or not it has a filter associated with
1795  *	it (filters make a trigger require access to the trace record
1796  *	but are not always present).
1797  */
1798 enum event_command_flags {
1799 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1800 	EVENT_CMD_FL_NEEDS_REC		= 2,
1801 };
1802 
event_command_post_trigger(struct event_command * cmd_ops)1803 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1804 {
1805 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1806 }
1807 
event_command_needs_rec(struct event_command * cmd_ops)1808 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1809 {
1810 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1811 }
1812 
1813 extern int trace_event_enable_disable(struct trace_event_file *file,
1814 				      int enable, int soft_disable);
1815 extern int tracing_alloc_snapshot(void);
1816 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1817 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1818 
1819 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1820 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1821 
1822 extern const char *__start___trace_bprintk_fmt[];
1823 extern const char *__stop___trace_bprintk_fmt[];
1824 
1825 extern const char *__start___tracepoint_str[];
1826 extern const char *__stop___tracepoint_str[];
1827 
1828 void trace_printk_control(bool enabled);
1829 void trace_printk_start_comm(void);
1830 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1831 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1832 
1833 /* Used from boot time tracer */
1834 extern int trace_set_options(struct trace_array *tr, char *option);
1835 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1836 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1837 					  unsigned long size, int cpu_id);
1838 extern int tracing_set_cpumask(struct trace_array *tr,
1839 				cpumask_var_t tracing_cpumask_new);
1840 
1841 
1842 #define MAX_EVENT_NAME_LEN	64
1843 
1844 extern ssize_t trace_parse_run_command(struct file *file,
1845 		const char __user *buffer, size_t count, loff_t *ppos,
1846 		int (*createfn)(const char *));
1847 
1848 extern unsigned int err_pos(char *cmd, const char *str);
1849 extern void tracing_log_err(struct trace_array *tr,
1850 			    const char *loc, const char *cmd,
1851 			    const char **errs, u8 type, u8 pos);
1852 
1853 /*
1854  * Normal trace_printk() and friends allocates special buffers
1855  * to do the manipulation, as well as saves the print formats
1856  * into sections to display. But the trace infrastructure wants
1857  * to use these without the added overhead at the price of being
1858  * a bit slower (used mainly for warnings, where we don't care
1859  * about performance). The internal_trace_puts() is for such
1860  * a purpose.
1861  */
1862 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1863 
1864 #undef FTRACE_ENTRY
1865 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1866 	extern struct trace_event_call					\
1867 	__aligned(4) event_##call;
1868 #undef FTRACE_ENTRY_DUP
1869 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1870 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1871 #undef FTRACE_ENTRY_PACKED
1872 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1873 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1874 
1875 #include "trace_entries.h"
1876 
1877 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1878 int perf_ftrace_event_register(struct trace_event_call *call,
1879 			       enum trace_reg type, void *data);
1880 #else
1881 #define perf_ftrace_event_register NULL
1882 #endif
1883 
1884 #ifdef CONFIG_FTRACE_SYSCALLS
1885 void init_ftrace_syscalls(void);
1886 const char *get_syscall_name(int syscall);
1887 #else
init_ftrace_syscalls(void)1888 static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)1889 static inline const char *get_syscall_name(int syscall)
1890 {
1891 	return NULL;
1892 }
1893 #endif
1894 
1895 #ifdef CONFIG_EVENT_TRACING
1896 void trace_event_init(void);
1897 void trace_event_eval_update(struct trace_eval_map **map, int len);
1898 /* Used from boot time tracer */
1899 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1900 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1901 #else
trace_event_init(void)1902 static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)1903 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1904 #endif
1905 
1906 #ifdef CONFIG_TRACER_SNAPSHOT
1907 void tracing_snapshot_instance(struct trace_array *tr);
1908 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1909 #else
tracing_snapshot_instance(struct trace_array * tr)1910 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)1911 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1912 {
1913 	return 0;
1914 }
1915 #endif
1916 
1917 #ifdef CONFIG_PREEMPT_TRACER
1918 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1919 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1920 #else
tracer_preempt_on(unsigned long a0,unsigned long a1)1921 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)1922 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1923 #endif
1924 #ifdef CONFIG_IRQSOFF_TRACER
1925 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1926 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1927 #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)1928 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)1929 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1930 #endif
1931 
1932 extern struct trace_iterator *tracepoint_print_iter;
1933 
1934 /*
1935  * Reset the state of the trace_iterator so that it can read consumed data.
1936  * Normally, the trace_iterator is used for reading the data when it is not
1937  * consumed, and must retain state.
1938  */
trace_iterator_reset(struct trace_iterator * iter)1939 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1940 {
1941 	const size_t offset = offsetof(struct trace_iterator, seq);
1942 
1943 	/*
1944 	 * Keep gcc from complaining about overwriting more than just one
1945 	 * member in the structure.
1946 	 */
1947 	memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1948 
1949 	iter->pos = -1;
1950 }
1951 
1952 /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)1953 static inline bool __is_good_name(const char *name, bool hash_ok)
1954 {
1955 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
1956 		return false;
1957 	while (*++name != '\0') {
1958 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
1959 		    (!hash_ok || *name != '-'))
1960 			return false;
1961 	}
1962 	return true;
1963 }
1964 
1965 /* Check the name is good for event/group/fields */
is_good_name(const char * name)1966 static inline bool is_good_name(const char *name)
1967 {
1968 	return __is_good_name(name, false);
1969 }
1970 
1971 /* Check the name is good for system */
is_good_system_name(const char * name)1972 static inline bool is_good_system_name(const char *name)
1973 {
1974 	return __is_good_name(name, true);
1975 }
1976 
1977 /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)1978 static inline void sanitize_event_name(char *name)
1979 {
1980 	while (*name++ != '\0')
1981 		if (*name == ':' || *name == '.')
1982 			*name = '_';
1983 }
1984 
1985 /*
1986  * This is a generic way to read and write a u64 value from a file in tracefs.
1987  *
1988  * The value is stored on the variable pointed by *val. The value needs
1989  * to be at least *min and at most *max. The write is protected by an
1990  * existing *lock.
1991  */
1992 struct trace_min_max_param {
1993 	struct mutex	*lock;
1994 	u64		*val;
1995 	u64		*min;
1996 	u64		*max;
1997 };
1998 
1999 #define U64_STR_SIZE		24	/* 20 digits max */
2000 
2001 extern const struct file_operations trace_min_max_fops;
2002 
2003 #endif /* _LINUX_KERNEL_TRACE_H */
2004