xref: /openbmc/linux/kernel/trace/trace.h (revision 1d7a0395)
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 #ifdef CONFIG_FTRACE_SYSCALLS
26 #include <asm/unistd.h>		/* For NR_SYSCALLS	     */
27 #include <asm/syscall.h>	/* some archs define it here */
28 #endif
29 
30 enum trace_type {
31 	__TRACE_FIRST_TYPE = 0,
32 
33 	TRACE_FN,
34 	TRACE_CTX,
35 	TRACE_WAKE,
36 	TRACE_STACK,
37 	TRACE_PRINT,
38 	TRACE_BPRINT,
39 	TRACE_MMIO_RW,
40 	TRACE_MMIO_MAP,
41 	TRACE_BRANCH,
42 	TRACE_GRAPH_RET,
43 	TRACE_GRAPH_ENT,
44 	TRACE_USER_STACK,
45 	TRACE_BLK,
46 	TRACE_BPUTS,
47 	TRACE_HWLAT,
48 	TRACE_RAW_DATA,
49 	TRACE_FUNC_REPEATS,
50 
51 	__TRACE_LAST_TYPE,
52 };
53 
54 
55 #undef __field
56 #define __field(type, item)		type	item;
57 
58 #undef __field_fn
59 #define __field_fn(type, item)		type	item;
60 
61 #undef __field_struct
62 #define __field_struct(type, item)	__field(type, item)
63 
64 #undef __field_desc
65 #define __field_desc(type, container, item)
66 
67 #undef __field_packed
68 #define __field_packed(type, container, item)
69 
70 #undef __array
71 #define __array(type, item, size)	type	item[size];
72 
73 #undef __array_desc
74 #define __array_desc(type, container, item, size)
75 
76 #undef __dynamic_array
77 #define __dynamic_array(type, item)	type	item[];
78 
79 #undef F_STRUCT
80 #define F_STRUCT(args...)		args
81 
82 #undef FTRACE_ENTRY
83 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
84 	struct struct_name {						\
85 		struct trace_entry	ent;				\
86 		tstruct							\
87 	}
88 
89 #undef FTRACE_ENTRY_DUP
90 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
91 
92 #undef FTRACE_ENTRY_REG
93 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
94 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
95 
96 #undef FTRACE_ENTRY_PACKED
97 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
98 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
99 
100 #include "trace_entries.h"
101 
102 /* Use this for memory failure errors */
103 #define MEM_FAIL(condition, fmt, ...)					\
104 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
105 
106 /*
107  * syscalls are special, and need special handling, this is why
108  * they are not included in trace_entries.h
109  */
110 struct syscall_trace_enter {
111 	struct trace_entry	ent;
112 	int			nr;
113 	unsigned long		args[];
114 };
115 
116 struct syscall_trace_exit {
117 	struct trace_entry	ent;
118 	int			nr;
119 	long			ret;
120 };
121 
122 struct kprobe_trace_entry_head {
123 	struct trace_entry	ent;
124 	unsigned long		ip;
125 };
126 
127 struct kretprobe_trace_entry_head {
128 	struct trace_entry	ent;
129 	unsigned long		func;
130 	unsigned long		ret_ip;
131 };
132 
133 #define TRACE_BUF_SIZE		1024
134 
135 struct trace_array;
136 
137 /*
138  * The CPU trace array - it consists of thousands of trace entries
139  * plus some other descriptor data: (for example which task started
140  * the trace, etc.)
141  */
142 struct trace_array_cpu {
143 	atomic_t		disabled;
144 	void			*buffer_page;	/* ring buffer spare */
145 
146 	unsigned long		entries;
147 	unsigned long		saved_latency;
148 	unsigned long		critical_start;
149 	unsigned long		critical_end;
150 	unsigned long		critical_sequence;
151 	unsigned long		nice;
152 	unsigned long		policy;
153 	unsigned long		rt_priority;
154 	unsigned long		skipped_entries;
155 	u64			preempt_timestamp;
156 	pid_t			pid;
157 	kuid_t			uid;
158 	char			comm[TASK_COMM_LEN];
159 
160 #ifdef CONFIG_FUNCTION_TRACER
161 	int			ftrace_ignore_pid;
162 #endif
163 	bool			ignore_pid;
164 };
165 
166 struct tracer;
167 struct trace_option_dentry;
168 
169 struct array_buffer {
170 	struct trace_array		*tr;
171 	struct trace_buffer		*buffer;
172 	struct trace_array_cpu __percpu	*data;
173 	u64				time_start;
174 	int				cpu;
175 };
176 
177 #define TRACE_FLAGS_MAX_SIZE		32
178 
179 struct trace_options {
180 	struct tracer			*tracer;
181 	struct trace_option_dentry	*topts;
182 };
183 
184 struct trace_pid_list {
185 	int				pid_max;
186 	unsigned long			*pids;
187 };
188 
189 enum {
190 	TRACE_PIDS		= BIT(0),
191 	TRACE_NO_PIDS		= BIT(1),
192 };
193 
194 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
195 				    struct trace_pid_list *no_pid_list)
196 {
197 	/* Return true if the pid list in type has pids */
198 	return ((type & TRACE_PIDS) && pid_list) ||
199 		((type & TRACE_NO_PIDS) && no_pid_list);
200 }
201 
202 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
203 					 struct trace_pid_list *no_pid_list)
204 {
205 	/*
206 	 * Turning off what is in @type, return true if the "other"
207 	 * pid list, still has pids in it.
208 	 */
209 	return (!(type & TRACE_PIDS) && pid_list) ||
210 		(!(type & TRACE_NO_PIDS) && no_pid_list);
211 }
212 
213 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
214 
215 /**
216  * struct cond_snapshot - conditional snapshot data and callback
217  *
218  * The cond_snapshot structure encapsulates a callback function and
219  * data associated with the snapshot for a given tracing instance.
220  *
221  * When a snapshot is taken conditionally, by invoking
222  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
223  * passed in turn to the cond_snapshot.update() function.  That data
224  * can be compared by the update() implementation with the cond_data
225  * contained within the struct cond_snapshot instance associated with
226  * the trace_array.  Because the tr->max_lock is held throughout the
227  * update() call, the update() function can directly retrieve the
228  * cond_snapshot and cond_data associated with the per-instance
229  * snapshot associated with the trace_array.
230  *
231  * The cond_snapshot.update() implementation can save data to be
232  * associated with the snapshot if it decides to, and returns 'true'
233  * in that case, or it returns 'false' if the conditional snapshot
234  * shouldn't be taken.
235  *
236  * The cond_snapshot instance is created and associated with the
237  * user-defined cond_data by tracing_cond_snapshot_enable().
238  * Likewise, the cond_snapshot instance is destroyed and is no longer
239  * associated with the trace instance by
240  * tracing_cond_snapshot_disable().
241  *
242  * The method below is required.
243  *
244  * @update: When a conditional snapshot is invoked, the update()
245  *	callback function is invoked with the tr->max_lock held.  The
246  *	update() implementation signals whether or not to actually
247  *	take the snapshot, by returning 'true' if so, 'false' if no
248  *	snapshot should be taken.  Because the max_lock is held for
249  *	the duration of update(), the implementation is safe to
250  *	directly retrieved and save any implementation data it needs
251  *	to in association with the snapshot.
252  */
253 struct cond_snapshot {
254 	void				*cond_data;
255 	cond_update_fn_t		update;
256 };
257 
258 /*
259  * struct trace_func_repeats - used to keep track of the consecutive
260  * (on the same CPU) calls of a single function.
261  */
262 struct trace_func_repeats {
263 	unsigned long	ip;
264 	unsigned long	parent_ip;
265 	unsigned long	count;
266 	u64		ts_last_call;
267 };
268 
269 /*
270  * The trace array - an array of per-CPU trace arrays. This is the
271  * highest level data structure that individual tracers deal with.
272  * They have on/off state as well:
273  */
274 struct trace_array {
275 	struct list_head	list;
276 	char			*name;
277 	struct array_buffer	array_buffer;
278 #ifdef CONFIG_TRACER_MAX_TRACE
279 	/*
280 	 * The max_buffer is used to snapshot the trace when a maximum
281 	 * latency is reached, or when the user initiates a snapshot.
282 	 * Some tracers will use this to store a maximum trace while
283 	 * it continues examining live traces.
284 	 *
285 	 * The buffers for the max_buffer are set up the same as the array_buffer
286 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
287 	 * with the buffer of the array_buffer and the buffers are reset for
288 	 * the array_buffer so the tracing can continue.
289 	 */
290 	struct array_buffer	max_buffer;
291 	bool			allocated_snapshot;
292 #endif
293 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
294 	unsigned long		max_latency;
295 #ifdef CONFIG_FSNOTIFY
296 	struct dentry		*d_max_latency;
297 	struct work_struct	fsnotify_work;
298 	struct irq_work		fsnotify_irqwork;
299 #endif
300 #endif
301 	struct trace_pid_list	__rcu *filtered_pids;
302 	struct trace_pid_list	__rcu *filtered_no_pids;
303 	/*
304 	 * max_lock is used to protect the swapping of buffers
305 	 * when taking a max snapshot. The buffers themselves are
306 	 * protected by per_cpu spinlocks. But the action of the swap
307 	 * needs its own lock.
308 	 *
309 	 * This is defined as a arch_spinlock_t in order to help
310 	 * with performance when lockdep debugging is enabled.
311 	 *
312 	 * It is also used in other places outside the update_max_tr
313 	 * so it needs to be defined outside of the
314 	 * CONFIG_TRACER_MAX_TRACE.
315 	 */
316 	arch_spinlock_t		max_lock;
317 	int			buffer_disabled;
318 #ifdef CONFIG_FTRACE_SYSCALLS
319 	int			sys_refcount_enter;
320 	int			sys_refcount_exit;
321 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
322 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
323 #endif
324 	int			stop_count;
325 	int			clock_id;
326 	int			nr_topts;
327 	bool			clear_trace;
328 	int			buffer_percent;
329 	unsigned int		n_err_log_entries;
330 	struct tracer		*current_trace;
331 	unsigned int		trace_flags;
332 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
333 	unsigned int		flags;
334 	raw_spinlock_t		start_lock;
335 	struct list_head	err_log;
336 	struct dentry		*dir;
337 	struct dentry		*options;
338 	struct dentry		*percpu_dir;
339 	struct dentry		*event_dir;
340 	struct trace_options	*topts;
341 	struct list_head	systems;
342 	struct list_head	events;
343 	struct trace_event_file *trace_marker_file;
344 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
345 	int			ref;
346 	int			trace_ref;
347 #ifdef CONFIG_FUNCTION_TRACER
348 	struct ftrace_ops	*ops;
349 	struct trace_pid_list	__rcu *function_pids;
350 	struct trace_pid_list	__rcu *function_no_pids;
351 #ifdef CONFIG_DYNAMIC_FTRACE
352 	/* All of these are protected by the ftrace_lock */
353 	struct list_head	func_probes;
354 	struct list_head	mod_trace;
355 	struct list_head	mod_notrace;
356 #endif
357 	/* function tracing enabled */
358 	int			function_enabled;
359 #endif
360 	int			no_filter_buffering_ref;
361 	struct list_head	hist_vars;
362 #ifdef CONFIG_TRACER_SNAPSHOT
363 	struct cond_snapshot	*cond_snapshot;
364 #endif
365 	struct trace_func_repeats	__percpu *last_func_repeats;
366 };
367 
368 enum {
369 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
370 };
371 
372 extern struct list_head ftrace_trace_arrays;
373 
374 extern struct mutex trace_types_lock;
375 
376 extern int trace_array_get(struct trace_array *tr);
377 extern int tracing_check_open_get_tr(struct trace_array *tr);
378 extern struct trace_array *trace_array_find(const char *instance);
379 extern struct trace_array *trace_array_find_get(const char *instance);
380 
381 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
382 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
383 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
384 
385 extern bool trace_clock_in_ns(struct trace_array *tr);
386 
387 /*
388  * The global tracer (top) should be the first trace array added,
389  * but we check the flag anyway.
390  */
391 static inline struct trace_array *top_trace_array(void)
392 {
393 	struct trace_array *tr;
394 
395 	if (list_empty(&ftrace_trace_arrays))
396 		return NULL;
397 
398 	tr = list_entry(ftrace_trace_arrays.prev,
399 			typeof(*tr), list);
400 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
401 	return tr;
402 }
403 
404 #define FTRACE_CMP_TYPE(var, type) \
405 	__builtin_types_compatible_p(typeof(var), type *)
406 
407 #undef IF_ASSIGN
408 #define IF_ASSIGN(var, entry, etype, id)			\
409 	if (FTRACE_CMP_TYPE(var, etype)) {			\
410 		var = (typeof(var))(entry);			\
411 		WARN_ON(id != 0 && (entry)->type != id);	\
412 		break;						\
413 	}
414 
415 /* Will cause compile errors if type is not found. */
416 extern void __ftrace_bad_type(void);
417 
418 /*
419  * The trace_assign_type is a verifier that the entry type is
420  * the same as the type being assigned. To add new types simply
421  * add a line with the following format:
422  *
423  * IF_ASSIGN(var, ent, type, id);
424  *
425  *  Where "type" is the trace type that includes the trace_entry
426  *  as the "ent" item. And "id" is the trace identifier that is
427  *  used in the trace_type enum.
428  *
429  *  If the type can have more than one id, then use zero.
430  */
431 #define trace_assign_type(var, ent)					\
432 	do {								\
433 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
434 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
435 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
436 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
437 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
438 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
439 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
440 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
441 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
442 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
443 			  TRACE_MMIO_RW);				\
444 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
445 			  TRACE_MMIO_MAP);				\
446 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
447 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
448 			  TRACE_GRAPH_ENT);		\
449 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
450 			  TRACE_GRAPH_RET);		\
451 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
452 			  TRACE_FUNC_REPEATS);				\
453 		__ftrace_bad_type();					\
454 	} while (0)
455 
456 /*
457  * An option specific to a tracer. This is a boolean value.
458  * The bit is the bit index that sets its value on the
459  * flags value in struct tracer_flags.
460  */
461 struct tracer_opt {
462 	const char	*name; /* Will appear on the trace_options file */
463 	u32		bit; /* Mask assigned in val field in tracer_flags */
464 };
465 
466 /*
467  * The set of specific options for a tracer. Your tracer
468  * have to set the initial value of the flags val.
469  */
470 struct tracer_flags {
471 	u32			val;
472 	struct tracer_opt	*opts;
473 	struct tracer		*trace;
474 };
475 
476 /* Makes more easy to define a tracer opt */
477 #define TRACER_OPT(s, b)	.name = #s, .bit = b
478 
479 
480 struct trace_option_dentry {
481 	struct tracer_opt		*opt;
482 	struct tracer_flags		*flags;
483 	struct trace_array		*tr;
484 	struct dentry			*entry;
485 };
486 
487 /**
488  * struct tracer - a specific tracer and its callbacks to interact with tracefs
489  * @name: the name chosen to select it on the available_tracers file
490  * @init: called when one switches to this tracer (echo name > current_tracer)
491  * @reset: called when one switches to another tracer
492  * @start: called when tracing is unpaused (echo 1 > tracing_on)
493  * @stop: called when tracing is paused (echo 0 > tracing_on)
494  * @update_thresh: called when tracing_thresh is updated
495  * @open: called when the trace file is opened
496  * @pipe_open: called when the trace_pipe file is opened
497  * @close: called when the trace file is released
498  * @pipe_close: called when the trace_pipe file is released
499  * @read: override the default read callback on trace_pipe
500  * @splice_read: override the default splice_read callback on trace_pipe
501  * @selftest: selftest to run on boot (see trace_selftest.c)
502  * @print_headers: override the first lines that describe your columns
503  * @print_line: callback that prints a trace
504  * @set_flag: signals one of your private flags changed (trace_options file)
505  * @flags: your private flags
506  */
507 struct tracer {
508 	const char		*name;
509 	int			(*init)(struct trace_array *tr);
510 	void			(*reset)(struct trace_array *tr);
511 	void			(*start)(struct trace_array *tr);
512 	void			(*stop)(struct trace_array *tr);
513 	int			(*update_thresh)(struct trace_array *tr);
514 	void			(*open)(struct trace_iterator *iter);
515 	void			(*pipe_open)(struct trace_iterator *iter);
516 	void			(*close)(struct trace_iterator *iter);
517 	void			(*pipe_close)(struct trace_iterator *iter);
518 	ssize_t			(*read)(struct trace_iterator *iter,
519 					struct file *filp, char __user *ubuf,
520 					size_t cnt, loff_t *ppos);
521 	ssize_t			(*splice_read)(struct trace_iterator *iter,
522 					       struct file *filp,
523 					       loff_t *ppos,
524 					       struct pipe_inode_info *pipe,
525 					       size_t len,
526 					       unsigned int flags);
527 #ifdef CONFIG_FTRACE_STARTUP_TEST
528 	int			(*selftest)(struct tracer *trace,
529 					    struct trace_array *tr);
530 #endif
531 	void			(*print_header)(struct seq_file *m);
532 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
533 	/* If you handled the flag setting, return 0 */
534 	int			(*set_flag)(struct trace_array *tr,
535 					    u32 old_flags, u32 bit, int set);
536 	/* Return 0 if OK with change, else return non-zero */
537 	int			(*flag_changed)(struct trace_array *tr,
538 						u32 mask, int set);
539 	struct tracer		*next;
540 	struct tracer_flags	*flags;
541 	int			enabled;
542 	bool			print_max;
543 	bool			allow_instances;
544 #ifdef CONFIG_TRACER_MAX_TRACE
545 	bool			use_max_tr;
546 #endif
547 	/* True if tracer cannot be enabled in kernel param */
548 	bool			noboot;
549 };
550 
551 static inline struct ring_buffer_iter *
552 trace_buffer_iter(struct trace_iterator *iter, int cpu)
553 {
554 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
555 }
556 
557 int tracer_init(struct tracer *t, struct trace_array *tr);
558 int tracing_is_enabled(void);
559 void tracing_reset_online_cpus(struct array_buffer *buf);
560 void tracing_reset_current(int cpu);
561 void tracing_reset_all_online_cpus(void);
562 int tracing_open_generic(struct inode *inode, struct file *filp);
563 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
564 bool tracing_is_disabled(void);
565 bool tracer_tracing_is_on(struct trace_array *tr);
566 void tracer_tracing_on(struct trace_array *tr);
567 void tracer_tracing_off(struct trace_array *tr);
568 struct dentry *trace_create_file(const char *name,
569 				 umode_t mode,
570 				 struct dentry *parent,
571 				 void *data,
572 				 const struct file_operations *fops);
573 
574 int tracing_init_dentry(void);
575 
576 struct ring_buffer_event;
577 
578 struct ring_buffer_event *
579 trace_buffer_lock_reserve(struct trace_buffer *buffer,
580 			  int type,
581 			  unsigned long len,
582 			  unsigned int trace_ctx);
583 
584 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
585 						struct trace_array_cpu *data);
586 
587 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
588 					  int *ent_cpu, u64 *ent_ts);
589 
590 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
591 					struct ring_buffer_event *event);
592 
593 bool trace_is_tracepoint_string(const char *str);
594 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
595 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
596 			 va_list ap);
597 
598 int trace_empty(struct trace_iterator *iter);
599 
600 void *trace_find_next_entry_inc(struct trace_iterator *iter);
601 
602 void trace_init_global_iter(struct trace_iterator *iter);
603 
604 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
605 
606 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
607 unsigned long trace_total_entries(struct trace_array *tr);
608 
609 void trace_function(struct trace_array *tr,
610 		    unsigned long ip,
611 		    unsigned long parent_ip,
612 		    unsigned int trace_ctx);
613 void trace_graph_function(struct trace_array *tr,
614 		    unsigned long ip,
615 		    unsigned long parent_ip,
616 		    unsigned int trace_ctx);
617 void trace_latency_header(struct seq_file *m);
618 void trace_default_header(struct seq_file *m);
619 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
620 
621 void trace_graph_return(struct ftrace_graph_ret *trace);
622 int trace_graph_entry(struct ftrace_graph_ent *trace);
623 void set_graph_array(struct trace_array *tr);
624 
625 void tracing_start_cmdline_record(void);
626 void tracing_stop_cmdline_record(void);
627 void tracing_start_tgid_record(void);
628 void tracing_stop_tgid_record(void);
629 
630 int register_tracer(struct tracer *type);
631 int is_tracing_stopped(void);
632 
633 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
634 
635 extern cpumask_var_t __read_mostly tracing_buffer_mask;
636 
637 #define for_each_tracing_cpu(cpu)	\
638 	for_each_cpu(cpu, tracing_buffer_mask)
639 
640 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
641 
642 extern unsigned long tracing_thresh;
643 
644 /* PID filtering */
645 
646 extern int pid_max;
647 
648 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
649 			     pid_t search_pid);
650 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
651 			    struct trace_pid_list *filtered_no_pids,
652 			    struct task_struct *task);
653 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
654 				  struct task_struct *self,
655 				  struct task_struct *task);
656 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
657 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
658 int trace_pid_show(struct seq_file *m, void *v);
659 void trace_free_pid_list(struct trace_pid_list *pid_list);
660 int trace_pid_write(struct trace_pid_list *filtered_pids,
661 		    struct trace_pid_list **new_pid_list,
662 		    const char __user *ubuf, size_t cnt);
663 
664 #ifdef CONFIG_TRACER_MAX_TRACE
665 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
666 		   void *cond_data);
667 void update_max_tr_single(struct trace_array *tr,
668 			  struct task_struct *tsk, int cpu);
669 #endif /* CONFIG_TRACER_MAX_TRACE */
670 
671 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
672 	defined(CONFIG_FSNOTIFY)
673 
674 void latency_fsnotify(struct trace_array *tr);
675 
676 #else
677 
678 static inline void latency_fsnotify(struct trace_array *tr) { }
679 
680 #endif
681 
682 #ifdef CONFIG_STACKTRACE
683 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
684 #else
685 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
686 				 int skip)
687 {
688 }
689 #endif /* CONFIG_STACKTRACE */
690 
691 void trace_last_func_repeats(struct trace_array *tr,
692 			     struct trace_func_repeats *last_info,
693 			     unsigned int trace_ctx);
694 
695 extern u64 ftrace_now(int cpu);
696 
697 extern void trace_find_cmdline(int pid, char comm[]);
698 extern int trace_find_tgid(int pid);
699 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
700 
701 #ifdef CONFIG_DYNAMIC_FTRACE
702 extern unsigned long ftrace_update_tot_cnt;
703 extern unsigned long ftrace_number_of_pages;
704 extern unsigned long ftrace_number_of_groups;
705 void ftrace_init_trace_array(struct trace_array *tr);
706 #else
707 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
708 #endif
709 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
710 extern int DYN_FTRACE_TEST_NAME(void);
711 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
712 extern int DYN_FTRACE_TEST_NAME2(void);
713 
714 extern bool ring_buffer_expanded;
715 extern bool tracing_selftest_disabled;
716 
717 #ifdef CONFIG_FTRACE_STARTUP_TEST
718 extern void __init disable_tracing_selftest(const char *reason);
719 
720 extern int trace_selftest_startup_function(struct tracer *trace,
721 					   struct trace_array *tr);
722 extern int trace_selftest_startup_function_graph(struct tracer *trace,
723 						 struct trace_array *tr);
724 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
725 					  struct trace_array *tr);
726 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
727 					     struct trace_array *tr);
728 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
729 						 struct trace_array *tr);
730 extern int trace_selftest_startup_wakeup(struct tracer *trace,
731 					 struct trace_array *tr);
732 extern int trace_selftest_startup_nop(struct tracer *trace,
733 					 struct trace_array *tr);
734 extern int trace_selftest_startup_branch(struct tracer *trace,
735 					 struct trace_array *tr);
736 /*
737  * Tracer data references selftest functions that only occur
738  * on boot up. These can be __init functions. Thus, when selftests
739  * are enabled, then the tracers need to reference __init functions.
740  */
741 #define __tracer_data		__refdata
742 #else
743 static inline void __init disable_tracing_selftest(const char *reason)
744 {
745 }
746 /* Tracers are seldom changed. Optimize when selftests are disabled. */
747 #define __tracer_data		__read_mostly
748 #endif /* CONFIG_FTRACE_STARTUP_TEST */
749 
750 extern void *head_page(struct trace_array_cpu *data);
751 extern unsigned long long ns2usecs(u64 nsec);
752 extern int
753 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
754 extern int
755 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
756 extern int
757 trace_array_vprintk(struct trace_array *tr,
758 		    unsigned long ip, const char *fmt, va_list args);
759 int trace_array_printk_buf(struct trace_buffer *buffer,
760 			   unsigned long ip, const char *fmt, ...);
761 void trace_printk_seq(struct trace_seq *s);
762 enum print_line_t print_trace_line(struct trace_iterator *iter);
763 
764 extern char trace_find_mark(unsigned long long duration);
765 
766 struct ftrace_hash;
767 
768 struct ftrace_mod_load {
769 	struct list_head	list;
770 	char			*func;
771 	char			*module;
772 	int			 enable;
773 };
774 
775 enum {
776 	FTRACE_HASH_FL_MOD	= (1 << 0),
777 };
778 
779 struct ftrace_hash {
780 	unsigned long		size_bits;
781 	struct hlist_head	*buckets;
782 	unsigned long		count;
783 	unsigned long		flags;
784 	struct rcu_head		rcu;
785 };
786 
787 struct ftrace_func_entry *
788 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
789 
790 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
791 {
792 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
793 }
794 
795 /* Standard output formatting function used for function return traces */
796 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
797 
798 /* Flag options */
799 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
800 #define TRACE_GRAPH_PRINT_CPU           0x2
801 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
802 #define TRACE_GRAPH_PRINT_PROC          0x8
803 #define TRACE_GRAPH_PRINT_DURATION      0x10
804 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
805 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
806 #define TRACE_GRAPH_PRINT_IRQS          0x80
807 #define TRACE_GRAPH_PRINT_TAIL          0x100
808 #define TRACE_GRAPH_SLEEP_TIME          0x200
809 #define TRACE_GRAPH_GRAPH_TIME          0x400
810 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
811 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
812 
813 extern void ftrace_graph_sleep_time_control(bool enable);
814 
815 #ifdef CONFIG_FUNCTION_PROFILER
816 extern void ftrace_graph_graph_time_control(bool enable);
817 #else
818 static inline void ftrace_graph_graph_time_control(bool enable) { }
819 #endif
820 
821 extern enum print_line_t
822 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
823 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
824 extern void
825 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
826 extern void graph_trace_open(struct trace_iterator *iter);
827 extern void graph_trace_close(struct trace_iterator *iter);
828 extern int __trace_graph_entry(struct trace_array *tr,
829 			       struct ftrace_graph_ent *trace,
830 			       unsigned int trace_ctx);
831 extern void __trace_graph_return(struct trace_array *tr,
832 				 struct ftrace_graph_ret *trace,
833 				 unsigned int trace_ctx);
834 
835 #ifdef CONFIG_DYNAMIC_FTRACE
836 extern struct ftrace_hash __rcu *ftrace_graph_hash;
837 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
838 
839 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
840 {
841 	unsigned long addr = trace->func;
842 	int ret = 0;
843 	struct ftrace_hash *hash;
844 
845 	preempt_disable_notrace();
846 
847 	/*
848 	 * Have to open code "rcu_dereference_sched()" because the
849 	 * function graph tracer can be called when RCU is not
850 	 * "watching".
851 	 * Protected with schedule_on_each_cpu(ftrace_sync)
852 	 */
853 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
854 
855 	if (ftrace_hash_empty(hash)) {
856 		ret = 1;
857 		goto out;
858 	}
859 
860 	if (ftrace_lookup_ip(hash, addr)) {
861 
862 		/*
863 		 * This needs to be cleared on the return functions
864 		 * when the depth is zero.
865 		 */
866 		trace_recursion_set(TRACE_GRAPH_BIT);
867 		trace_recursion_set_depth(trace->depth);
868 
869 		/*
870 		 * If no irqs are to be traced, but a set_graph_function
871 		 * is set, and called by an interrupt handler, we still
872 		 * want to trace it.
873 		 */
874 		if (in_irq())
875 			trace_recursion_set(TRACE_IRQ_BIT);
876 		else
877 			trace_recursion_clear(TRACE_IRQ_BIT);
878 		ret = 1;
879 	}
880 
881 out:
882 	preempt_enable_notrace();
883 	return ret;
884 }
885 
886 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
887 {
888 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
889 	    trace->depth == trace_recursion_depth())
890 		trace_recursion_clear(TRACE_GRAPH_BIT);
891 }
892 
893 static inline int ftrace_graph_notrace_addr(unsigned long addr)
894 {
895 	int ret = 0;
896 	struct ftrace_hash *notrace_hash;
897 
898 	preempt_disable_notrace();
899 
900 	/*
901 	 * Have to open code "rcu_dereference_sched()" because the
902 	 * function graph tracer can be called when RCU is not
903 	 * "watching".
904 	 * Protected with schedule_on_each_cpu(ftrace_sync)
905 	 */
906 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
907 						 !preemptible());
908 
909 	if (ftrace_lookup_ip(notrace_hash, addr))
910 		ret = 1;
911 
912 	preempt_enable_notrace();
913 	return ret;
914 }
915 #else
916 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
917 {
918 	return 1;
919 }
920 
921 static inline int ftrace_graph_notrace_addr(unsigned long addr)
922 {
923 	return 0;
924 }
925 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
926 { }
927 #endif /* CONFIG_DYNAMIC_FTRACE */
928 
929 extern unsigned int fgraph_max_depth;
930 
931 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
932 {
933 	/* trace it when it is-nested-in or is a function enabled. */
934 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
935 		 ftrace_graph_addr(trace)) ||
936 		(trace->depth < 0) ||
937 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
938 }
939 
940 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
941 static inline enum print_line_t
942 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
943 {
944 	return TRACE_TYPE_UNHANDLED;
945 }
946 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
947 
948 extern struct list_head ftrace_pids;
949 
950 #ifdef CONFIG_FUNCTION_TRACER
951 
952 #define FTRACE_PID_IGNORE	-1
953 #define FTRACE_PID_TRACE	-2
954 
955 struct ftrace_func_command {
956 	struct list_head	list;
957 	char			*name;
958 	int			(*func)(struct trace_array *tr,
959 					struct ftrace_hash *hash,
960 					char *func, char *cmd,
961 					char *params, int enable);
962 };
963 extern bool ftrace_filter_param __initdata;
964 static inline int ftrace_trace_task(struct trace_array *tr)
965 {
966 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
967 		FTRACE_PID_IGNORE;
968 }
969 extern int ftrace_is_dead(void);
970 int ftrace_create_function_files(struct trace_array *tr,
971 				 struct dentry *parent);
972 void ftrace_destroy_function_files(struct trace_array *tr);
973 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
974 void ftrace_free_ftrace_ops(struct trace_array *tr);
975 void ftrace_init_global_array_ops(struct trace_array *tr);
976 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
977 void ftrace_reset_array_ops(struct trace_array *tr);
978 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
979 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
980 				  struct dentry *d_tracer);
981 void ftrace_clear_pids(struct trace_array *tr);
982 int init_function_trace(void);
983 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
984 #else
985 static inline int ftrace_trace_task(struct trace_array *tr)
986 {
987 	return 1;
988 }
989 static inline int ftrace_is_dead(void) { return 0; }
990 static inline int
991 ftrace_create_function_files(struct trace_array *tr,
992 			     struct dentry *parent)
993 {
994 	return 0;
995 }
996 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
997 {
998 	return 0;
999 }
1000 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1001 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1002 static inline __init void
1003 ftrace_init_global_array_ops(struct trace_array *tr) { }
1004 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1005 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1006 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1007 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1008 static inline int init_function_trace(void) { return 0; }
1009 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1010 /* ftace_func_t type is not defined, use macro instead of static inline */
1011 #define ftrace_init_array_ops(tr, func) do { } while (0)
1012 #endif /* CONFIG_FUNCTION_TRACER */
1013 
1014 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1015 
1016 struct ftrace_probe_ops {
1017 	void			(*func)(unsigned long ip,
1018 					unsigned long parent_ip,
1019 					struct trace_array *tr,
1020 					struct ftrace_probe_ops *ops,
1021 					void *data);
1022 	int			(*init)(struct ftrace_probe_ops *ops,
1023 					struct trace_array *tr,
1024 					unsigned long ip, void *init_data,
1025 					void **data);
1026 	void			(*free)(struct ftrace_probe_ops *ops,
1027 					struct trace_array *tr,
1028 					unsigned long ip, void *data);
1029 	int			(*print)(struct seq_file *m,
1030 					 unsigned long ip,
1031 					 struct ftrace_probe_ops *ops,
1032 					 void *data);
1033 };
1034 
1035 struct ftrace_func_mapper;
1036 typedef int (*ftrace_mapper_func)(void *data);
1037 
1038 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1039 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1040 					   unsigned long ip);
1041 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1042 			       unsigned long ip, void *data);
1043 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1044 				   unsigned long ip);
1045 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1046 			     ftrace_mapper_func free_func);
1047 
1048 extern int
1049 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1050 			       struct ftrace_probe_ops *ops, void *data);
1051 extern int
1052 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1053 				      struct ftrace_probe_ops *ops);
1054 extern void clear_ftrace_function_probes(struct trace_array *tr);
1055 
1056 int register_ftrace_command(struct ftrace_func_command *cmd);
1057 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1058 
1059 void ftrace_create_filter_files(struct ftrace_ops *ops,
1060 				struct dentry *parent);
1061 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1062 
1063 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1064 			     int len, int reset);
1065 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1066 			      int len, int reset);
1067 #else
1068 struct ftrace_func_command;
1069 
1070 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1071 {
1072 	return -EINVAL;
1073 }
1074 static inline __init int unregister_ftrace_command(char *cmd_name)
1075 {
1076 	return -EINVAL;
1077 }
1078 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1079 {
1080 }
1081 
1082 /*
1083  * The ops parameter passed in is usually undefined.
1084  * This must be a macro.
1085  */
1086 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1087 #define ftrace_destroy_filter_files(ops) do { } while (0)
1088 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1089 
1090 bool ftrace_event_is_function(struct trace_event_call *call);
1091 
1092 /*
1093  * struct trace_parser - servers for reading the user input separated by spaces
1094  * @cont: set if the input is not complete - no final space char was found
1095  * @buffer: holds the parsed user input
1096  * @idx: user input length
1097  * @size: buffer size
1098  */
1099 struct trace_parser {
1100 	bool		cont;
1101 	char		*buffer;
1102 	unsigned	idx;
1103 	unsigned	size;
1104 };
1105 
1106 static inline bool trace_parser_loaded(struct trace_parser *parser)
1107 {
1108 	return (parser->idx != 0);
1109 }
1110 
1111 static inline bool trace_parser_cont(struct trace_parser *parser)
1112 {
1113 	return parser->cont;
1114 }
1115 
1116 static inline void trace_parser_clear(struct trace_parser *parser)
1117 {
1118 	parser->cont = false;
1119 	parser->idx = 0;
1120 }
1121 
1122 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1123 extern void trace_parser_put(struct trace_parser *parser);
1124 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1125 	size_t cnt, loff_t *ppos);
1126 
1127 /*
1128  * Only create function graph options if function graph is configured.
1129  */
1130 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1131 # define FGRAPH_FLAGS						\
1132 		C(DISPLAY_GRAPH,	"display-graph"),
1133 #else
1134 # define FGRAPH_FLAGS
1135 #endif
1136 
1137 #ifdef CONFIG_BRANCH_TRACER
1138 # define BRANCH_FLAGS					\
1139 		C(BRANCH,		"branch"),
1140 #else
1141 # define BRANCH_FLAGS
1142 #endif
1143 
1144 #ifdef CONFIG_FUNCTION_TRACER
1145 # define FUNCTION_FLAGS						\
1146 		C(FUNCTION,		"function-trace"),	\
1147 		C(FUNC_FORK,		"function-fork"),
1148 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1149 #else
1150 # define FUNCTION_FLAGS
1151 # define FUNCTION_DEFAULT_FLAGS		0UL
1152 # define TRACE_ITER_FUNC_FORK		0UL
1153 #endif
1154 
1155 #ifdef CONFIG_STACKTRACE
1156 # define STACK_FLAGS				\
1157 		C(STACKTRACE,		"stacktrace"),
1158 #else
1159 # define STACK_FLAGS
1160 #endif
1161 
1162 /*
1163  * trace_iterator_flags is an enumeration that defines bit
1164  * positions into trace_flags that controls the output.
1165  *
1166  * NOTE: These bits must match the trace_options array in
1167  *       trace.c (this macro guarantees it).
1168  */
1169 #define TRACE_FLAGS						\
1170 		C(PRINT_PARENT,		"print-parent"),	\
1171 		C(SYM_OFFSET,		"sym-offset"),		\
1172 		C(SYM_ADDR,		"sym-addr"),		\
1173 		C(VERBOSE,		"verbose"),		\
1174 		C(RAW,			"raw"),			\
1175 		C(HEX,			"hex"),			\
1176 		C(BIN,			"bin"),			\
1177 		C(BLOCK,		"block"),		\
1178 		C(PRINTK,		"trace_printk"),	\
1179 		C(ANNOTATE,		"annotate"),		\
1180 		C(USERSTACKTRACE,	"userstacktrace"),	\
1181 		C(SYM_USEROBJ,		"sym-userobj"),		\
1182 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1183 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1184 		C(LATENCY_FMT,		"latency-format"),	\
1185 		C(RECORD_CMD,		"record-cmd"),		\
1186 		C(RECORD_TGID,		"record-tgid"),		\
1187 		C(OVERWRITE,		"overwrite"),		\
1188 		C(STOP_ON_FREE,		"disable_on_free"),	\
1189 		C(IRQ_INFO,		"irq-info"),		\
1190 		C(MARKERS,		"markers"),		\
1191 		C(EVENT_FORK,		"event-fork"),		\
1192 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1193 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1194 		FUNCTION_FLAGS					\
1195 		FGRAPH_FLAGS					\
1196 		STACK_FLAGS					\
1197 		BRANCH_FLAGS
1198 
1199 /*
1200  * By defining C, we can make TRACE_FLAGS a list of bit names
1201  * that will define the bits for the flag masks.
1202  */
1203 #undef C
1204 #define C(a, b) TRACE_ITER_##a##_BIT
1205 
1206 enum trace_iterator_bits {
1207 	TRACE_FLAGS
1208 	/* Make sure we don't go more than we have bits for */
1209 	TRACE_ITER_LAST_BIT
1210 };
1211 
1212 /*
1213  * By redefining C, we can make TRACE_FLAGS a list of masks that
1214  * use the bits as defined above.
1215  */
1216 #undef C
1217 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1218 
1219 enum trace_iterator_flags { TRACE_FLAGS };
1220 
1221 /*
1222  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1223  * control the output of kernel symbols.
1224  */
1225 #define TRACE_ITER_SYM_MASK \
1226 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1227 
1228 extern struct tracer nop_trace;
1229 
1230 #ifdef CONFIG_BRANCH_TRACER
1231 extern int enable_branch_tracing(struct trace_array *tr);
1232 extern void disable_branch_tracing(void);
1233 static inline int trace_branch_enable(struct trace_array *tr)
1234 {
1235 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1236 		return enable_branch_tracing(tr);
1237 	return 0;
1238 }
1239 static inline void trace_branch_disable(void)
1240 {
1241 	/* due to races, always disable */
1242 	disable_branch_tracing();
1243 }
1244 #else
1245 static inline int trace_branch_enable(struct trace_array *tr)
1246 {
1247 	return 0;
1248 }
1249 static inline void trace_branch_disable(void)
1250 {
1251 }
1252 #endif /* CONFIG_BRANCH_TRACER */
1253 
1254 /* set ring buffers to default size if not already done so */
1255 int tracing_update_buffers(void);
1256 
1257 struct ftrace_event_field {
1258 	struct list_head	link;
1259 	const char		*name;
1260 	const char		*type;
1261 	int			filter_type;
1262 	int			offset;
1263 	int			size;
1264 	int			is_signed;
1265 };
1266 
1267 struct prog_entry;
1268 
1269 struct event_filter {
1270 	struct prog_entry __rcu	*prog;
1271 	char			*filter_string;
1272 };
1273 
1274 struct event_subsystem {
1275 	struct list_head	list;
1276 	const char		*name;
1277 	struct event_filter	*filter;
1278 	int			ref_count;
1279 };
1280 
1281 struct trace_subsystem_dir {
1282 	struct list_head		list;
1283 	struct event_subsystem		*subsystem;
1284 	struct trace_array		*tr;
1285 	struct dentry			*entry;
1286 	int				ref_count;
1287 	int				nr_events;
1288 };
1289 
1290 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1291 				     struct trace_buffer *buffer,
1292 				     struct ring_buffer_event *event);
1293 
1294 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1295 				     struct trace_buffer *buffer,
1296 				     struct ring_buffer_event *event,
1297 				     unsigned int trcace_ctx,
1298 				     struct pt_regs *regs);
1299 
1300 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1301 					      struct trace_buffer *buffer,
1302 					      struct ring_buffer_event *event,
1303 					      unsigned int trace_ctx)
1304 {
1305 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1306 }
1307 
1308 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1309 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1310 void trace_buffered_event_disable(void);
1311 void trace_buffered_event_enable(void);
1312 
1313 static inline void
1314 __trace_event_discard_commit(struct trace_buffer *buffer,
1315 			     struct ring_buffer_event *event)
1316 {
1317 	if (this_cpu_read(trace_buffered_event) == event) {
1318 		/* Simply release the temp buffer */
1319 		this_cpu_dec(trace_buffered_event_cnt);
1320 		return;
1321 	}
1322 	ring_buffer_discard_commit(buffer, event);
1323 }
1324 
1325 /*
1326  * Helper function for event_trigger_unlock_commit{_regs}().
1327  * If there are event triggers attached to this event that requires
1328  * filtering against its fields, then they will be called as the
1329  * entry already holds the field information of the current event.
1330  *
1331  * It also checks if the event should be discarded or not.
1332  * It is to be discarded if the event is soft disabled and the
1333  * event was only recorded to process triggers, or if the event
1334  * filter is active and this event did not match the filters.
1335  *
1336  * Returns true if the event is discarded, false otherwise.
1337  */
1338 static inline bool
1339 __event_trigger_test_discard(struct trace_event_file *file,
1340 			     struct trace_buffer *buffer,
1341 			     struct ring_buffer_event *event,
1342 			     void *entry,
1343 			     enum event_trigger_type *tt)
1344 {
1345 	unsigned long eflags = file->flags;
1346 
1347 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1348 		*tt = event_triggers_call(file, buffer, entry, event);
1349 
1350 	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1351 	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1352 	     !filter_match_preds(file->filter, entry))) {
1353 		__trace_event_discard_commit(buffer, event);
1354 		return true;
1355 	}
1356 
1357 	return false;
1358 }
1359 
1360 /**
1361  * event_trigger_unlock_commit - handle triggers and finish event commit
1362  * @file: The file pointer associated with the event
1363  * @buffer: The ring buffer that the event is being written to
1364  * @event: The event meta data in the ring buffer
1365  * @entry: The event itself
1366  * @trace_ctx: The tracing context flags.
1367  *
1368  * This is a helper function to handle triggers that require data
1369  * from the event itself. It also tests the event against filters and
1370  * if the event is soft disabled and should be discarded.
1371  */
1372 static inline void
1373 event_trigger_unlock_commit(struct trace_event_file *file,
1374 			    struct trace_buffer *buffer,
1375 			    struct ring_buffer_event *event,
1376 			    void *entry, unsigned int trace_ctx)
1377 {
1378 	enum event_trigger_type tt = ETT_NONE;
1379 
1380 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1381 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1382 
1383 	if (tt)
1384 		event_triggers_post_call(file, tt);
1385 }
1386 
1387 /**
1388  * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1389  * @file: The file pointer associated with the event
1390  * @buffer: The ring buffer that the event is being written to
1391  * @event: The event meta data in the ring buffer
1392  * @entry: The event itself
1393  * @trace_ctx: The tracing context flags.
1394  *
1395  * This is a helper function to handle triggers that require data
1396  * from the event itself. It also tests the event against filters and
1397  * if the event is soft disabled and should be discarded.
1398  *
1399  * Same as event_trigger_unlock_commit() but calls
1400  * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1401  */
1402 static inline void
1403 event_trigger_unlock_commit_regs(struct trace_event_file *file,
1404 				 struct trace_buffer *buffer,
1405 				 struct ring_buffer_event *event,
1406 				 void *entry, unsigned int trace_ctx,
1407 				 struct pt_regs *regs)
1408 {
1409 	enum event_trigger_type tt = ETT_NONE;
1410 
1411 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1412 		trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1413 						trace_ctx, regs);
1414 
1415 	if (tt)
1416 		event_triggers_post_call(file, tt);
1417 }
1418 
1419 #define FILTER_PRED_INVALID	((unsigned short)-1)
1420 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1421 #define FILTER_PRED_FOLD	(1 << 15)
1422 
1423 /*
1424  * The max preds is the size of unsigned short with
1425  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1426  * and FOLD flags. The other is reserved.
1427  *
1428  * 2^14 preds is way more than enough.
1429  */
1430 #define MAX_FILTER_PRED		16384
1431 
1432 struct filter_pred;
1433 struct regex;
1434 
1435 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1436 
1437 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1438 
1439 enum regex_type {
1440 	MATCH_FULL = 0,
1441 	MATCH_FRONT_ONLY,
1442 	MATCH_MIDDLE_ONLY,
1443 	MATCH_END_ONLY,
1444 	MATCH_GLOB,
1445 	MATCH_INDEX,
1446 };
1447 
1448 struct regex {
1449 	char			pattern[MAX_FILTER_STR_VAL];
1450 	int			len;
1451 	int			field_len;
1452 	regex_match_func	match;
1453 };
1454 
1455 struct filter_pred {
1456 	filter_pred_fn_t 	fn;
1457 	u64 			val;
1458 	struct regex		regex;
1459 	unsigned short		*ops;
1460 	struct ftrace_event_field *field;
1461 	int 			offset;
1462 	int			not;
1463 	int 			op;
1464 };
1465 
1466 static inline bool is_string_field(struct ftrace_event_field *field)
1467 {
1468 	return field->filter_type == FILTER_DYN_STRING ||
1469 	       field->filter_type == FILTER_STATIC_STRING ||
1470 	       field->filter_type == FILTER_PTR_STRING ||
1471 	       field->filter_type == FILTER_COMM;
1472 }
1473 
1474 static inline bool is_function_field(struct ftrace_event_field *field)
1475 {
1476 	return field->filter_type == FILTER_TRACE_FN;
1477 }
1478 
1479 extern enum regex_type
1480 filter_parse_regex(char *buff, int len, char **search, int *not);
1481 extern void print_event_filter(struct trace_event_file *file,
1482 			       struct trace_seq *s);
1483 extern int apply_event_filter(struct trace_event_file *file,
1484 			      char *filter_string);
1485 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1486 					char *filter_string);
1487 extern void print_subsystem_event_filter(struct event_subsystem *system,
1488 					 struct trace_seq *s);
1489 extern int filter_assign_type(const char *type);
1490 extern int create_event_filter(struct trace_array *tr,
1491 			       struct trace_event_call *call,
1492 			       char *filter_str, bool set_str,
1493 			       struct event_filter **filterp);
1494 extern void free_event_filter(struct event_filter *filter);
1495 
1496 struct ftrace_event_field *
1497 trace_find_event_field(struct trace_event_call *call, char *name);
1498 
1499 extern void trace_event_enable_cmd_record(bool enable);
1500 extern void trace_event_enable_tgid_record(bool enable);
1501 
1502 extern int event_trace_init(void);
1503 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1504 extern int event_trace_del_tracer(struct trace_array *tr);
1505 extern void __trace_early_add_events(struct trace_array *tr);
1506 
1507 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1508 						  const char *system,
1509 						  const char *event);
1510 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1511 						const char *system,
1512 						const char *event);
1513 
1514 static inline void *event_file_data(struct file *filp)
1515 {
1516 	return READ_ONCE(file_inode(filp)->i_private);
1517 }
1518 
1519 extern struct mutex event_mutex;
1520 extern struct list_head ftrace_events;
1521 
1522 extern const struct file_operations event_trigger_fops;
1523 extern const struct file_operations event_hist_fops;
1524 extern const struct file_operations event_hist_debug_fops;
1525 extern const struct file_operations event_inject_fops;
1526 
1527 #ifdef CONFIG_HIST_TRIGGERS
1528 extern int register_trigger_hist_cmd(void);
1529 extern int register_trigger_hist_enable_disable_cmds(void);
1530 #else
1531 static inline int register_trigger_hist_cmd(void) { return 0; }
1532 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1533 #endif
1534 
1535 extern int register_trigger_cmds(void);
1536 extern void clear_event_triggers(struct trace_array *tr);
1537 
1538 struct event_trigger_data {
1539 	unsigned long			count;
1540 	int				ref;
1541 	struct event_trigger_ops	*ops;
1542 	struct event_command		*cmd_ops;
1543 	struct event_filter __rcu	*filter;
1544 	char				*filter_str;
1545 	void				*private_data;
1546 	bool				paused;
1547 	bool				paused_tmp;
1548 	struct list_head		list;
1549 	char				*name;
1550 	struct list_head		named_list;
1551 	struct event_trigger_data	*named_data;
1552 };
1553 
1554 /* Avoid typos */
1555 #define ENABLE_EVENT_STR	"enable_event"
1556 #define DISABLE_EVENT_STR	"disable_event"
1557 #define ENABLE_HIST_STR		"enable_hist"
1558 #define DISABLE_HIST_STR	"disable_hist"
1559 
1560 struct enable_trigger_data {
1561 	struct trace_event_file		*file;
1562 	bool				enable;
1563 	bool				hist;
1564 };
1565 
1566 extern int event_enable_trigger_print(struct seq_file *m,
1567 				      struct event_trigger_ops *ops,
1568 				      struct event_trigger_data *data);
1569 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1570 				      struct event_trigger_data *data);
1571 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1572 				     struct trace_event_file *file,
1573 				     char *glob, char *cmd, char *param);
1574 extern int event_enable_register_trigger(char *glob,
1575 					 struct event_trigger_ops *ops,
1576 					 struct event_trigger_data *data,
1577 					 struct trace_event_file *file);
1578 extern void event_enable_unregister_trigger(char *glob,
1579 					    struct event_trigger_ops *ops,
1580 					    struct event_trigger_data *test,
1581 					    struct trace_event_file *file);
1582 extern void trigger_data_free(struct event_trigger_data *data);
1583 extern int event_trigger_init(struct event_trigger_ops *ops,
1584 			      struct event_trigger_data *data);
1585 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1586 					      int trigger_enable);
1587 extern void update_cond_flag(struct trace_event_file *file);
1588 extern int set_trigger_filter(char *filter_str,
1589 			      struct event_trigger_data *trigger_data,
1590 			      struct trace_event_file *file);
1591 extern struct event_trigger_data *find_named_trigger(const char *name);
1592 extern bool is_named_trigger(struct event_trigger_data *test);
1593 extern int save_named_trigger(const char *name,
1594 			      struct event_trigger_data *data);
1595 extern void del_named_trigger(struct event_trigger_data *data);
1596 extern void pause_named_trigger(struct event_trigger_data *data);
1597 extern void unpause_named_trigger(struct event_trigger_data *data);
1598 extern void set_named_trigger_data(struct event_trigger_data *data,
1599 				   struct event_trigger_data *named_data);
1600 extern struct event_trigger_data *
1601 get_named_trigger_data(struct event_trigger_data *data);
1602 extern int register_event_command(struct event_command *cmd);
1603 extern int unregister_event_command(struct event_command *cmd);
1604 extern int register_trigger_hist_enable_disable_cmds(void);
1605 
1606 /**
1607  * struct event_trigger_ops - callbacks for trace event triggers
1608  *
1609  * The methods in this structure provide per-event trigger hooks for
1610  * various trigger operations.
1611  *
1612  * All the methods below, except for @init() and @free(), must be
1613  * implemented.
1614  *
1615  * @func: The trigger 'probe' function called when the triggering
1616  *	event occurs.  The data passed into this callback is the data
1617  *	that was supplied to the event_command @reg() function that
1618  *	registered the trigger (see struct event_command) along with
1619  *	the trace record, rec.
1620  *
1621  * @init: An optional initialization function called for the trigger
1622  *	when the trigger is registered (via the event_command reg()
1623  *	function).  This can be used to perform per-trigger
1624  *	initialization such as incrementing a per-trigger reference
1625  *	count, for instance.  This is usually implemented by the
1626  *	generic utility function @event_trigger_init() (see
1627  *	trace_event_triggers.c).
1628  *
1629  * @free: An optional de-initialization function called for the
1630  *	trigger when the trigger is unregistered (via the
1631  *	event_command @reg() function).  This can be used to perform
1632  *	per-trigger de-initialization such as decrementing a
1633  *	per-trigger reference count and freeing corresponding trigger
1634  *	data, for instance.  This is usually implemented by the
1635  *	generic utility function @event_trigger_free() (see
1636  *	trace_event_triggers.c).
1637  *
1638  * @print: The callback function invoked to have the trigger print
1639  *	itself.  This is usually implemented by a wrapper function
1640  *	that calls the generic utility function @event_trigger_print()
1641  *	(see trace_event_triggers.c).
1642  */
1643 struct event_trigger_ops {
1644 	void			(*func)(struct event_trigger_data *data,
1645 					struct trace_buffer *buffer, void *rec,
1646 					struct ring_buffer_event *rbe);
1647 	int			(*init)(struct event_trigger_ops *ops,
1648 					struct event_trigger_data *data);
1649 	void			(*free)(struct event_trigger_ops *ops,
1650 					struct event_trigger_data *data);
1651 	int			(*print)(struct seq_file *m,
1652 					 struct event_trigger_ops *ops,
1653 					 struct event_trigger_data *data);
1654 };
1655 
1656 /**
1657  * struct event_command - callbacks and data members for event commands
1658  *
1659  * Event commands are invoked by users by writing the command name
1660  * into the 'trigger' file associated with a trace event.  The
1661  * parameters associated with a specific invocation of an event
1662  * command are used to create an event trigger instance, which is
1663  * added to the list of trigger instances associated with that trace
1664  * event.  When the event is hit, the set of triggers associated with
1665  * that event is invoked.
1666  *
1667  * The data members in this structure provide per-event command data
1668  * for various event commands.
1669  *
1670  * All the data members below, except for @post_trigger, must be set
1671  * for each event command.
1672  *
1673  * @name: The unique name that identifies the event command.  This is
1674  *	the name used when setting triggers via trigger files.
1675  *
1676  * @trigger_type: A unique id that identifies the event command
1677  *	'type'.  This value has two purposes, the first to ensure that
1678  *	only one trigger of the same type can be set at a given time
1679  *	for a particular event e.g. it doesn't make sense to have both
1680  *	a traceon and traceoff trigger attached to a single event at
1681  *	the same time, so traceon and traceoff have the same type
1682  *	though they have different names.  The @trigger_type value is
1683  *	also used as a bit value for deferring the actual trigger
1684  *	action until after the current event is finished.  Some
1685  *	commands need to do this if they themselves log to the trace
1686  *	buffer (see the @post_trigger() member below).  @trigger_type
1687  *	values are defined by adding new values to the trigger_type
1688  *	enum in include/linux/trace_events.h.
1689  *
1690  * @flags: See the enum event_command_flags below.
1691  *
1692  * All the methods below, except for @set_filter() and @unreg_all(),
1693  * must be implemented.
1694  *
1695  * @func: The callback function responsible for parsing and
1696  *	registering the trigger written to the 'trigger' file by the
1697  *	user.  It allocates the trigger instance and registers it with
1698  *	the appropriate trace event.  It makes use of the other
1699  *	event_command callback functions to orchestrate this, and is
1700  *	usually implemented by the generic utility function
1701  *	@event_trigger_callback() (see trace_event_triggers.c).
1702  *
1703  * @reg: Adds the trigger to the list of triggers associated with the
1704  *	event, and enables the event trigger itself, after
1705  *	initializing it (via the event_trigger_ops @init() function).
1706  *	This is also where commands can use the @trigger_type value to
1707  *	make the decision as to whether or not multiple instances of
1708  *	the trigger should be allowed.  This is usually implemented by
1709  *	the generic utility function @register_trigger() (see
1710  *	trace_event_triggers.c).
1711  *
1712  * @unreg: Removes the trigger from the list of triggers associated
1713  *	with the event, and disables the event trigger itself, after
1714  *	initializing it (via the event_trigger_ops @free() function).
1715  *	This is usually implemented by the generic utility function
1716  *	@unregister_trigger() (see trace_event_triggers.c).
1717  *
1718  * @unreg_all: An optional function called to remove all the triggers
1719  *	from the list of triggers associated with the event.  Called
1720  *	when a trigger file is opened in truncate mode.
1721  *
1722  * @set_filter: An optional function called to parse and set a filter
1723  *	for the trigger.  If no @set_filter() method is set for the
1724  *	event command, filters set by the user for the command will be
1725  *	ignored.  This is usually implemented by the generic utility
1726  *	function @set_trigger_filter() (see trace_event_triggers.c).
1727  *
1728  * @get_trigger_ops: The callback function invoked to retrieve the
1729  *	event_trigger_ops implementation associated with the command.
1730  */
1731 struct event_command {
1732 	struct list_head	list;
1733 	char			*name;
1734 	enum event_trigger_type	trigger_type;
1735 	int			flags;
1736 	int			(*func)(struct event_command *cmd_ops,
1737 					struct trace_event_file *file,
1738 					char *glob, char *cmd, char *params);
1739 	int			(*reg)(char *glob,
1740 				       struct event_trigger_ops *ops,
1741 				       struct event_trigger_data *data,
1742 				       struct trace_event_file *file);
1743 	void			(*unreg)(char *glob,
1744 					 struct event_trigger_ops *ops,
1745 					 struct event_trigger_data *data,
1746 					 struct trace_event_file *file);
1747 	void			(*unreg_all)(struct trace_event_file *file);
1748 	int			(*set_filter)(char *filter_str,
1749 					      struct event_trigger_data *data,
1750 					      struct trace_event_file *file);
1751 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1752 };
1753 
1754 /**
1755  * enum event_command_flags - flags for struct event_command
1756  *
1757  * @POST_TRIGGER: A flag that says whether or not this command needs
1758  *	to have its action delayed until after the current event has
1759  *	been closed.  Some triggers need to avoid being invoked while
1760  *	an event is currently in the process of being logged, since
1761  *	the trigger may itself log data into the trace buffer.  Thus
1762  *	we make sure the current event is committed before invoking
1763  *	those triggers.  To do that, the trigger invocation is split
1764  *	in two - the first part checks the filter using the current
1765  *	trace record; if a command has the @post_trigger flag set, it
1766  *	sets a bit for itself in the return value, otherwise it
1767  *	directly invokes the trigger.  Once all commands have been
1768  *	either invoked or set their return flag, the current record is
1769  *	either committed or discarded.  At that point, if any commands
1770  *	have deferred their triggers, those commands are finally
1771  *	invoked following the close of the current event.  In other
1772  *	words, if the event_trigger_ops @func() probe implementation
1773  *	itself logs to the trace buffer, this flag should be set,
1774  *	otherwise it can be left unspecified.
1775  *
1776  * @NEEDS_REC: A flag that says whether or not this command needs
1777  *	access to the trace record in order to perform its function,
1778  *	regardless of whether or not it has a filter associated with
1779  *	it (filters make a trigger require access to the trace record
1780  *	but are not always present).
1781  */
1782 enum event_command_flags {
1783 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1784 	EVENT_CMD_FL_NEEDS_REC		= 2,
1785 };
1786 
1787 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1788 {
1789 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1790 }
1791 
1792 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1793 {
1794 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1795 }
1796 
1797 extern int trace_event_enable_disable(struct trace_event_file *file,
1798 				      int enable, int soft_disable);
1799 extern int tracing_alloc_snapshot(void);
1800 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1801 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1802 
1803 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1804 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1805 
1806 extern const char *__start___trace_bprintk_fmt[];
1807 extern const char *__stop___trace_bprintk_fmt[];
1808 
1809 extern const char *__start___tracepoint_str[];
1810 extern const char *__stop___tracepoint_str[];
1811 
1812 void trace_printk_control(bool enabled);
1813 void trace_printk_start_comm(void);
1814 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1815 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1816 
1817 /* Used from boot time tracer */
1818 extern int trace_set_options(struct trace_array *tr, char *option);
1819 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1820 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1821 					  unsigned long size, int cpu_id);
1822 extern int tracing_set_cpumask(struct trace_array *tr,
1823 				cpumask_var_t tracing_cpumask_new);
1824 
1825 
1826 #define MAX_EVENT_NAME_LEN	64
1827 
1828 extern ssize_t trace_parse_run_command(struct file *file,
1829 		const char __user *buffer, size_t count, loff_t *ppos,
1830 		int (*createfn)(const char *));
1831 
1832 extern unsigned int err_pos(char *cmd, const char *str);
1833 extern void tracing_log_err(struct trace_array *tr,
1834 			    const char *loc, const char *cmd,
1835 			    const char **errs, u8 type, u8 pos);
1836 
1837 /*
1838  * Normal trace_printk() and friends allocates special buffers
1839  * to do the manipulation, as well as saves the print formats
1840  * into sections to display. But the trace infrastructure wants
1841  * to use these without the added overhead at the price of being
1842  * a bit slower (used mainly for warnings, where we don't care
1843  * about performance). The internal_trace_puts() is for such
1844  * a purpose.
1845  */
1846 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1847 
1848 #undef FTRACE_ENTRY
1849 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1850 	extern struct trace_event_call					\
1851 	__aligned(4) event_##call;
1852 #undef FTRACE_ENTRY_DUP
1853 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1854 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1855 #undef FTRACE_ENTRY_PACKED
1856 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1857 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1858 
1859 #include "trace_entries.h"
1860 
1861 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1862 int perf_ftrace_event_register(struct trace_event_call *call,
1863 			       enum trace_reg type, void *data);
1864 #else
1865 #define perf_ftrace_event_register NULL
1866 #endif
1867 
1868 #ifdef CONFIG_FTRACE_SYSCALLS
1869 void init_ftrace_syscalls(void);
1870 const char *get_syscall_name(int syscall);
1871 #else
1872 static inline void init_ftrace_syscalls(void) { }
1873 static inline const char *get_syscall_name(int syscall)
1874 {
1875 	return NULL;
1876 }
1877 #endif
1878 
1879 #ifdef CONFIG_EVENT_TRACING
1880 void trace_event_init(void);
1881 void trace_event_eval_update(struct trace_eval_map **map, int len);
1882 /* Used from boot time tracer */
1883 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1884 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1885 #else
1886 static inline void __init trace_event_init(void) { }
1887 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1888 #endif
1889 
1890 #ifdef CONFIG_TRACER_SNAPSHOT
1891 void tracing_snapshot_instance(struct trace_array *tr);
1892 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1893 #else
1894 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1895 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1896 {
1897 	return 0;
1898 }
1899 #endif
1900 
1901 #ifdef CONFIG_PREEMPT_TRACER
1902 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1903 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1904 #else
1905 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1906 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1907 #endif
1908 #ifdef CONFIG_IRQSOFF_TRACER
1909 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1910 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1911 #else
1912 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1913 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1914 #endif
1915 
1916 extern struct trace_iterator *tracepoint_print_iter;
1917 
1918 /*
1919  * Reset the state of the trace_iterator so that it can read consumed data.
1920  * Normally, the trace_iterator is used for reading the data when it is not
1921  * consumed, and must retain state.
1922  */
1923 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1924 {
1925 	const size_t offset = offsetof(struct trace_iterator, seq);
1926 
1927 	/*
1928 	 * Keep gcc from complaining about overwriting more than just one
1929 	 * member in the structure.
1930 	 */
1931 	memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1932 
1933 	iter->pos = -1;
1934 }
1935 
1936 /* Check the name is good for event/group/fields */
1937 static inline bool is_good_name(const char *name)
1938 {
1939 	if (!isalpha(*name) && *name != '_')
1940 		return false;
1941 	while (*++name != '\0') {
1942 		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1943 			return false;
1944 	}
1945 	return true;
1946 }
1947 
1948 #endif /* _LINUX_KERNEL_TRACE_H */
1949