xref: /openbmc/linux/kernel/trace/trace.h (revision ee7da21a)
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_OSNOISE,
49 	TRACE_TIMERLAT,
50 	TRACE_RAW_DATA,
51 	TRACE_FUNC_REPEATS,
52 
53 	__TRACE_LAST_TYPE,
54 };
55 
56 
57 #undef __field
58 #define __field(type, item)		type	item;
59 
60 #undef __field_fn
61 #define __field_fn(type, item)		type	item;
62 
63 #undef __field_struct
64 #define __field_struct(type, item)	__field(type, item)
65 
66 #undef __field_desc
67 #define __field_desc(type, container, item)
68 
69 #undef __field_packed
70 #define __field_packed(type, container, item)
71 
72 #undef __array
73 #define __array(type, item, size)	type	item[size];
74 
75 #undef __array_desc
76 #define __array_desc(type, container, item, size)
77 
78 #undef __dynamic_array
79 #define __dynamic_array(type, item)	type	item[];
80 
81 #undef F_STRUCT
82 #define F_STRUCT(args...)		args
83 
84 #undef FTRACE_ENTRY
85 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
86 	struct struct_name {						\
87 		struct trace_entry	ent;				\
88 		tstruct							\
89 	}
90 
91 #undef FTRACE_ENTRY_DUP
92 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
93 
94 #undef FTRACE_ENTRY_REG
95 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
96 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
97 
98 #undef FTRACE_ENTRY_PACKED
99 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
100 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
101 
102 #include "trace_entries.h"
103 
104 /* Use this for memory failure errors */
105 #define MEM_FAIL(condition, fmt, ...)					\
106 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
107 
108 /*
109  * syscalls are special, and need special handling, this is why
110  * they are not included in trace_entries.h
111  */
112 struct syscall_trace_enter {
113 	struct trace_entry	ent;
114 	int			nr;
115 	unsigned long		args[];
116 };
117 
118 struct syscall_trace_exit {
119 	struct trace_entry	ent;
120 	int			nr;
121 	long			ret;
122 };
123 
124 struct kprobe_trace_entry_head {
125 	struct trace_entry	ent;
126 	unsigned long		ip;
127 };
128 
129 struct kretprobe_trace_entry_head {
130 	struct trace_entry	ent;
131 	unsigned long		func;
132 	unsigned long		ret_ip;
133 };
134 
135 #define TRACE_BUF_SIZE		1024
136 
137 struct trace_array;
138 
139 /*
140  * The CPU trace array - it consists of thousands of trace entries
141  * plus some other descriptor data: (for example which task started
142  * the trace, etc.)
143  */
144 struct trace_array_cpu {
145 	atomic_t		disabled;
146 	void			*buffer_page;	/* ring buffer spare */
147 
148 	unsigned long		entries;
149 	unsigned long		saved_latency;
150 	unsigned long		critical_start;
151 	unsigned long		critical_end;
152 	unsigned long		critical_sequence;
153 	unsigned long		nice;
154 	unsigned long		policy;
155 	unsigned long		rt_priority;
156 	unsigned long		skipped_entries;
157 	u64			preempt_timestamp;
158 	pid_t			pid;
159 	kuid_t			uid;
160 	char			comm[TASK_COMM_LEN];
161 
162 #ifdef CONFIG_FUNCTION_TRACER
163 	int			ftrace_ignore_pid;
164 #endif
165 	bool			ignore_pid;
166 };
167 
168 struct tracer;
169 struct trace_option_dentry;
170 
171 struct array_buffer {
172 	struct trace_array		*tr;
173 	struct trace_buffer		*buffer;
174 	struct trace_array_cpu __percpu	*data;
175 	u64				time_start;
176 	int				cpu;
177 };
178 
179 #define TRACE_FLAGS_MAX_SIZE		32
180 
181 struct trace_options {
182 	struct tracer			*tracer;
183 	struct trace_option_dentry	*topts;
184 };
185 
186 struct trace_pid_list {
187 	int				pid_max;
188 	unsigned long			*pids;
189 };
190 
191 enum {
192 	TRACE_PIDS		= BIT(0),
193 	TRACE_NO_PIDS		= BIT(1),
194 };
195 
196 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
197 				    struct trace_pid_list *no_pid_list)
198 {
199 	/* Return true if the pid list in type has pids */
200 	return ((type & TRACE_PIDS) && pid_list) ||
201 		((type & TRACE_NO_PIDS) && no_pid_list);
202 }
203 
204 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
205 					 struct trace_pid_list *no_pid_list)
206 {
207 	/*
208 	 * Turning off what is in @type, return true if the "other"
209 	 * pid list, still has pids in it.
210 	 */
211 	return (!(type & TRACE_PIDS) && pid_list) ||
212 		(!(type & TRACE_NO_PIDS) && no_pid_list);
213 }
214 
215 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
216 
217 /**
218  * struct cond_snapshot - conditional snapshot data and callback
219  *
220  * The cond_snapshot structure encapsulates a callback function and
221  * data associated with the snapshot for a given tracing instance.
222  *
223  * When a snapshot is taken conditionally, by invoking
224  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
225  * passed in turn to the cond_snapshot.update() function.  That data
226  * can be compared by the update() implementation with the cond_data
227  * contained within the struct cond_snapshot instance associated with
228  * the trace_array.  Because the tr->max_lock is held throughout the
229  * update() call, the update() function can directly retrieve the
230  * cond_snapshot and cond_data associated with the per-instance
231  * snapshot associated with the trace_array.
232  *
233  * The cond_snapshot.update() implementation can save data to be
234  * associated with the snapshot if it decides to, and returns 'true'
235  * in that case, or it returns 'false' if the conditional snapshot
236  * shouldn't be taken.
237  *
238  * The cond_snapshot instance is created and associated with the
239  * user-defined cond_data by tracing_cond_snapshot_enable().
240  * Likewise, the cond_snapshot instance is destroyed and is no longer
241  * associated with the trace instance by
242  * tracing_cond_snapshot_disable().
243  *
244  * The method below is required.
245  *
246  * @update: When a conditional snapshot is invoked, the update()
247  *	callback function is invoked with the tr->max_lock held.  The
248  *	update() implementation signals whether or not to actually
249  *	take the snapshot, by returning 'true' if so, 'false' if no
250  *	snapshot should be taken.  Because the max_lock is held for
251  *	the duration of update(), the implementation is safe to
252  *	directly retrieved and save any implementation data it needs
253  *	to in association with the snapshot.
254  */
255 struct cond_snapshot {
256 	void				*cond_data;
257 	cond_update_fn_t		update;
258 };
259 
260 /*
261  * struct trace_func_repeats - used to keep track of the consecutive
262  * (on the same CPU) calls of a single function.
263  */
264 struct trace_func_repeats {
265 	unsigned long	ip;
266 	unsigned long	parent_ip;
267 	unsigned long	count;
268 	u64		ts_last_call;
269 };
270 
271 /*
272  * The trace array - an array of per-CPU trace arrays. This is the
273  * highest level data structure that individual tracers deal with.
274  * They have on/off state as well:
275  */
276 struct trace_array {
277 	struct list_head	list;
278 	char			*name;
279 	struct array_buffer	array_buffer;
280 #ifdef CONFIG_TRACER_MAX_TRACE
281 	/*
282 	 * The max_buffer is used to snapshot the trace when a maximum
283 	 * latency is reached, or when the user initiates a snapshot.
284 	 * Some tracers will use this to store a maximum trace while
285 	 * it continues examining live traces.
286 	 *
287 	 * The buffers for the max_buffer are set up the same as the array_buffer
288 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
289 	 * with the buffer of the array_buffer and the buffers are reset for
290 	 * the array_buffer so the tracing can continue.
291 	 */
292 	struct array_buffer	max_buffer;
293 	bool			allocated_snapshot;
294 #endif
295 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
296 	|| defined(CONFIG_OSNOISE_TRACER)
297 	unsigned long		max_latency;
298 #ifdef CONFIG_FSNOTIFY
299 	struct dentry		*d_max_latency;
300 	struct work_struct	fsnotify_work;
301 	struct irq_work		fsnotify_irqwork;
302 #endif
303 #endif
304 	struct trace_pid_list	__rcu *filtered_pids;
305 	struct trace_pid_list	__rcu *filtered_no_pids;
306 	/*
307 	 * max_lock is used to protect the swapping of buffers
308 	 * when taking a max snapshot. The buffers themselves are
309 	 * protected by per_cpu spinlocks. But the action of the swap
310 	 * needs its own lock.
311 	 *
312 	 * This is defined as a arch_spinlock_t in order to help
313 	 * with performance when lockdep debugging is enabled.
314 	 *
315 	 * It is also used in other places outside the update_max_tr
316 	 * so it needs to be defined outside of the
317 	 * CONFIG_TRACER_MAX_TRACE.
318 	 */
319 	arch_spinlock_t		max_lock;
320 	int			buffer_disabled;
321 #ifdef CONFIG_FTRACE_SYSCALLS
322 	int			sys_refcount_enter;
323 	int			sys_refcount_exit;
324 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
325 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
326 #endif
327 	int			stop_count;
328 	int			clock_id;
329 	int			nr_topts;
330 	bool			clear_trace;
331 	int			buffer_percent;
332 	unsigned int		n_err_log_entries;
333 	struct tracer		*current_trace;
334 	unsigned int		trace_flags;
335 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
336 	unsigned int		flags;
337 	raw_spinlock_t		start_lock;
338 	struct list_head	err_log;
339 	struct dentry		*dir;
340 	struct dentry		*options;
341 	struct dentry		*percpu_dir;
342 	struct dentry		*event_dir;
343 	struct trace_options	*topts;
344 	struct list_head	systems;
345 	struct list_head	events;
346 	struct trace_event_file *trace_marker_file;
347 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
348 	int			ref;
349 	int			trace_ref;
350 #ifdef CONFIG_FUNCTION_TRACER
351 	struct ftrace_ops	*ops;
352 	struct trace_pid_list	__rcu *function_pids;
353 	struct trace_pid_list	__rcu *function_no_pids;
354 #ifdef CONFIG_DYNAMIC_FTRACE
355 	/* All of these are protected by the ftrace_lock */
356 	struct list_head	func_probes;
357 	struct list_head	mod_trace;
358 	struct list_head	mod_notrace;
359 #endif
360 	/* function tracing enabled */
361 	int			function_enabled;
362 #endif
363 	int			no_filter_buffering_ref;
364 	struct list_head	hist_vars;
365 #ifdef CONFIG_TRACER_SNAPSHOT
366 	struct cond_snapshot	*cond_snapshot;
367 #endif
368 	struct trace_func_repeats	__percpu *last_func_repeats;
369 };
370 
371 enum {
372 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
373 };
374 
375 extern struct list_head ftrace_trace_arrays;
376 
377 extern struct mutex trace_types_lock;
378 
379 extern int trace_array_get(struct trace_array *tr);
380 extern int tracing_check_open_get_tr(struct trace_array *tr);
381 extern struct trace_array *trace_array_find(const char *instance);
382 extern struct trace_array *trace_array_find_get(const char *instance);
383 
384 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
385 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
386 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
387 
388 extern bool trace_clock_in_ns(struct trace_array *tr);
389 
390 /*
391  * The global tracer (top) should be the first trace array added,
392  * but we check the flag anyway.
393  */
394 static inline struct trace_array *top_trace_array(void)
395 {
396 	struct trace_array *tr;
397 
398 	if (list_empty(&ftrace_trace_arrays))
399 		return NULL;
400 
401 	tr = list_entry(ftrace_trace_arrays.prev,
402 			typeof(*tr), list);
403 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
404 	return tr;
405 }
406 
407 #define FTRACE_CMP_TYPE(var, type) \
408 	__builtin_types_compatible_p(typeof(var), type *)
409 
410 #undef IF_ASSIGN
411 #define IF_ASSIGN(var, entry, etype, id)			\
412 	if (FTRACE_CMP_TYPE(var, etype)) {			\
413 		var = (typeof(var))(entry);			\
414 		WARN_ON(id != 0 && (entry)->type != id);	\
415 		break;						\
416 	}
417 
418 /* Will cause compile errors if type is not found. */
419 extern void __ftrace_bad_type(void);
420 
421 /*
422  * The trace_assign_type is a verifier that the entry type is
423  * the same as the type being assigned. To add new types simply
424  * add a line with the following format:
425  *
426  * IF_ASSIGN(var, ent, type, id);
427  *
428  *  Where "type" is the trace type that includes the trace_entry
429  *  as the "ent" item. And "id" is the trace identifier that is
430  *  used in the trace_type enum.
431  *
432  *  If the type can have more than one id, then use zero.
433  */
434 #define trace_assign_type(var, ent)					\
435 	do {								\
436 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
437 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
438 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
439 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
440 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
441 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
442 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
443 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
444 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
445 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
446 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
447 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
448 			  TRACE_MMIO_RW);				\
449 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
450 			  TRACE_MMIO_MAP);				\
451 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
452 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
453 			  TRACE_GRAPH_ENT);		\
454 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
455 			  TRACE_GRAPH_RET);		\
456 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
457 			  TRACE_FUNC_REPEATS);				\
458 		__ftrace_bad_type();					\
459 	} while (0)
460 
461 /*
462  * An option specific to a tracer. This is a boolean value.
463  * The bit is the bit index that sets its value on the
464  * flags value in struct tracer_flags.
465  */
466 struct tracer_opt {
467 	const char	*name; /* Will appear on the trace_options file */
468 	u32		bit; /* Mask assigned in val field in tracer_flags */
469 };
470 
471 /*
472  * The set of specific options for a tracer. Your tracer
473  * have to set the initial value of the flags val.
474  */
475 struct tracer_flags {
476 	u32			val;
477 	struct tracer_opt	*opts;
478 	struct tracer		*trace;
479 };
480 
481 /* Makes more easy to define a tracer opt */
482 #define TRACER_OPT(s, b)	.name = #s, .bit = b
483 
484 
485 struct trace_option_dentry {
486 	struct tracer_opt		*opt;
487 	struct tracer_flags		*flags;
488 	struct trace_array		*tr;
489 	struct dentry			*entry;
490 };
491 
492 /**
493  * struct tracer - a specific tracer and its callbacks to interact with tracefs
494  * @name: the name chosen to select it on the available_tracers file
495  * @init: called when one switches to this tracer (echo name > current_tracer)
496  * @reset: called when one switches to another tracer
497  * @start: called when tracing is unpaused (echo 1 > tracing_on)
498  * @stop: called when tracing is paused (echo 0 > tracing_on)
499  * @update_thresh: called when tracing_thresh is updated
500  * @open: called when the trace file is opened
501  * @pipe_open: called when the trace_pipe file is opened
502  * @close: called when the trace file is released
503  * @pipe_close: called when the trace_pipe file is released
504  * @read: override the default read callback on trace_pipe
505  * @splice_read: override the default splice_read callback on trace_pipe
506  * @selftest: selftest to run on boot (see trace_selftest.c)
507  * @print_headers: override the first lines that describe your columns
508  * @print_line: callback that prints a trace
509  * @set_flag: signals one of your private flags changed (trace_options file)
510  * @flags: your private flags
511  */
512 struct tracer {
513 	const char		*name;
514 	int			(*init)(struct trace_array *tr);
515 	void			(*reset)(struct trace_array *tr);
516 	void			(*start)(struct trace_array *tr);
517 	void			(*stop)(struct trace_array *tr);
518 	int			(*update_thresh)(struct trace_array *tr);
519 	void			(*open)(struct trace_iterator *iter);
520 	void			(*pipe_open)(struct trace_iterator *iter);
521 	void			(*close)(struct trace_iterator *iter);
522 	void			(*pipe_close)(struct trace_iterator *iter);
523 	ssize_t			(*read)(struct trace_iterator *iter,
524 					struct file *filp, char __user *ubuf,
525 					size_t cnt, loff_t *ppos);
526 	ssize_t			(*splice_read)(struct trace_iterator *iter,
527 					       struct file *filp,
528 					       loff_t *ppos,
529 					       struct pipe_inode_info *pipe,
530 					       size_t len,
531 					       unsigned int flags);
532 #ifdef CONFIG_FTRACE_STARTUP_TEST
533 	int			(*selftest)(struct tracer *trace,
534 					    struct trace_array *tr);
535 #endif
536 	void			(*print_header)(struct seq_file *m);
537 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
538 	/* If you handled the flag setting, return 0 */
539 	int			(*set_flag)(struct trace_array *tr,
540 					    u32 old_flags, u32 bit, int set);
541 	/* Return 0 if OK with change, else return non-zero */
542 	int			(*flag_changed)(struct trace_array *tr,
543 						u32 mask, int set);
544 	struct tracer		*next;
545 	struct tracer_flags	*flags;
546 	int			enabled;
547 	bool			print_max;
548 	bool			allow_instances;
549 #ifdef CONFIG_TRACER_MAX_TRACE
550 	bool			use_max_tr;
551 #endif
552 	/* True if tracer cannot be enabled in kernel param */
553 	bool			noboot;
554 };
555 
556 static inline struct ring_buffer_iter *
557 trace_buffer_iter(struct trace_iterator *iter, int cpu)
558 {
559 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
560 }
561 
562 int tracer_init(struct tracer *t, struct trace_array *tr);
563 int tracing_is_enabled(void);
564 void tracing_reset_online_cpus(struct array_buffer *buf);
565 void tracing_reset_current(int cpu);
566 void tracing_reset_all_online_cpus(void);
567 int tracing_open_generic(struct inode *inode, struct file *filp);
568 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
569 bool tracing_is_disabled(void);
570 bool tracer_tracing_is_on(struct trace_array *tr);
571 void tracer_tracing_on(struct trace_array *tr);
572 void tracer_tracing_off(struct trace_array *tr);
573 struct dentry *trace_create_file(const char *name,
574 				 umode_t mode,
575 				 struct dentry *parent,
576 				 void *data,
577 				 const struct file_operations *fops);
578 
579 int tracing_init_dentry(void);
580 
581 struct ring_buffer_event;
582 
583 struct ring_buffer_event *
584 trace_buffer_lock_reserve(struct trace_buffer *buffer,
585 			  int type,
586 			  unsigned long len,
587 			  unsigned int trace_ctx);
588 
589 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
590 						struct trace_array_cpu *data);
591 
592 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
593 					  int *ent_cpu, u64 *ent_ts);
594 
595 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
596 					struct ring_buffer_event *event);
597 
598 bool trace_is_tracepoint_string(const char *str);
599 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
600 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
601 			 va_list ap);
602 
603 int trace_empty(struct trace_iterator *iter);
604 
605 void *trace_find_next_entry_inc(struct trace_iterator *iter);
606 
607 void trace_init_global_iter(struct trace_iterator *iter);
608 
609 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
610 
611 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
612 unsigned long trace_total_entries(struct trace_array *tr);
613 
614 void trace_function(struct trace_array *tr,
615 		    unsigned long ip,
616 		    unsigned long parent_ip,
617 		    unsigned int trace_ctx);
618 void trace_graph_function(struct trace_array *tr,
619 		    unsigned long ip,
620 		    unsigned long parent_ip,
621 		    unsigned int trace_ctx);
622 void trace_latency_header(struct seq_file *m);
623 void trace_default_header(struct seq_file *m);
624 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
625 
626 void trace_graph_return(struct ftrace_graph_ret *trace);
627 int trace_graph_entry(struct ftrace_graph_ent *trace);
628 void set_graph_array(struct trace_array *tr);
629 
630 void tracing_start_cmdline_record(void);
631 void tracing_stop_cmdline_record(void);
632 void tracing_start_tgid_record(void);
633 void tracing_stop_tgid_record(void);
634 
635 int register_tracer(struct tracer *type);
636 int is_tracing_stopped(void);
637 
638 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
639 
640 extern cpumask_var_t __read_mostly tracing_buffer_mask;
641 
642 #define for_each_tracing_cpu(cpu)	\
643 	for_each_cpu(cpu, tracing_buffer_mask)
644 
645 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
646 
647 extern unsigned long tracing_thresh;
648 
649 /* PID filtering */
650 
651 extern int pid_max;
652 
653 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
654 			     pid_t search_pid);
655 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
656 			    struct trace_pid_list *filtered_no_pids,
657 			    struct task_struct *task);
658 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
659 				  struct task_struct *self,
660 				  struct task_struct *task);
661 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
662 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
663 int trace_pid_show(struct seq_file *m, void *v);
664 void trace_free_pid_list(struct trace_pid_list *pid_list);
665 int trace_pid_write(struct trace_pid_list *filtered_pids,
666 		    struct trace_pid_list **new_pid_list,
667 		    const char __user *ubuf, size_t cnt);
668 
669 #ifdef CONFIG_TRACER_MAX_TRACE
670 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
671 		   void *cond_data);
672 void update_max_tr_single(struct trace_array *tr,
673 			  struct task_struct *tsk, int cpu);
674 #endif /* CONFIG_TRACER_MAX_TRACE */
675 
676 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
677 	|| defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY)
678 #define LATENCY_FS_NOTIFY
679 #endif
680 
681 #ifdef LATENCY_FS_NOTIFY
682 void latency_fsnotify(struct trace_array *tr);
683 #else
684 static inline void latency_fsnotify(struct trace_array *tr) { }
685 #endif
686 
687 #ifdef CONFIG_STACKTRACE
688 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
689 #else
690 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
691 				 int skip)
692 {
693 }
694 #endif /* CONFIG_STACKTRACE */
695 
696 void trace_last_func_repeats(struct trace_array *tr,
697 			     struct trace_func_repeats *last_info,
698 			     unsigned int trace_ctx);
699 
700 extern u64 ftrace_now(int cpu);
701 
702 extern void trace_find_cmdline(int pid, char comm[]);
703 extern int trace_find_tgid(int pid);
704 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
705 
706 #ifdef CONFIG_DYNAMIC_FTRACE
707 extern unsigned long ftrace_update_tot_cnt;
708 extern unsigned long ftrace_number_of_pages;
709 extern unsigned long ftrace_number_of_groups;
710 void ftrace_init_trace_array(struct trace_array *tr);
711 #else
712 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
713 #endif
714 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
715 extern int DYN_FTRACE_TEST_NAME(void);
716 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
717 extern int DYN_FTRACE_TEST_NAME2(void);
718 
719 extern bool ring_buffer_expanded;
720 extern bool tracing_selftest_disabled;
721 
722 #ifdef CONFIG_FTRACE_STARTUP_TEST
723 extern void __init disable_tracing_selftest(const char *reason);
724 
725 extern int trace_selftest_startup_function(struct tracer *trace,
726 					   struct trace_array *tr);
727 extern int trace_selftest_startup_function_graph(struct tracer *trace,
728 						 struct trace_array *tr);
729 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
730 					  struct trace_array *tr);
731 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
732 					     struct trace_array *tr);
733 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
734 						 struct trace_array *tr);
735 extern int trace_selftest_startup_wakeup(struct tracer *trace,
736 					 struct trace_array *tr);
737 extern int trace_selftest_startup_nop(struct tracer *trace,
738 					 struct trace_array *tr);
739 extern int trace_selftest_startup_branch(struct tracer *trace,
740 					 struct trace_array *tr);
741 /*
742  * Tracer data references selftest functions that only occur
743  * on boot up. These can be __init functions. Thus, when selftests
744  * are enabled, then the tracers need to reference __init functions.
745  */
746 #define __tracer_data		__refdata
747 #else
748 static inline void __init disable_tracing_selftest(const char *reason)
749 {
750 }
751 /* Tracers are seldom changed. Optimize when selftests are disabled. */
752 #define __tracer_data		__read_mostly
753 #endif /* CONFIG_FTRACE_STARTUP_TEST */
754 
755 extern void *head_page(struct trace_array_cpu *data);
756 extern unsigned long long ns2usecs(u64 nsec);
757 extern int
758 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
759 extern int
760 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
761 extern int
762 trace_array_vprintk(struct trace_array *tr,
763 		    unsigned long ip, const char *fmt, va_list args);
764 int trace_array_printk_buf(struct trace_buffer *buffer,
765 			   unsigned long ip, const char *fmt, ...);
766 void trace_printk_seq(struct trace_seq *s);
767 enum print_line_t print_trace_line(struct trace_iterator *iter);
768 
769 extern char trace_find_mark(unsigned long long duration);
770 
771 struct ftrace_hash;
772 
773 struct ftrace_mod_load {
774 	struct list_head	list;
775 	char			*func;
776 	char			*module;
777 	int			 enable;
778 };
779 
780 enum {
781 	FTRACE_HASH_FL_MOD	= (1 << 0),
782 };
783 
784 struct ftrace_hash {
785 	unsigned long		size_bits;
786 	struct hlist_head	*buckets;
787 	unsigned long		count;
788 	unsigned long		flags;
789 	struct rcu_head		rcu;
790 };
791 
792 struct ftrace_func_entry *
793 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
794 
795 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
796 {
797 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
798 }
799 
800 /* Standard output formatting function used for function return traces */
801 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
802 
803 /* Flag options */
804 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
805 #define TRACE_GRAPH_PRINT_CPU           0x2
806 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
807 #define TRACE_GRAPH_PRINT_PROC          0x8
808 #define TRACE_GRAPH_PRINT_DURATION      0x10
809 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
810 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
811 #define TRACE_GRAPH_PRINT_IRQS          0x80
812 #define TRACE_GRAPH_PRINT_TAIL          0x100
813 #define TRACE_GRAPH_SLEEP_TIME          0x200
814 #define TRACE_GRAPH_GRAPH_TIME          0x400
815 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
816 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
817 
818 extern void ftrace_graph_sleep_time_control(bool enable);
819 
820 #ifdef CONFIG_FUNCTION_PROFILER
821 extern void ftrace_graph_graph_time_control(bool enable);
822 #else
823 static inline void ftrace_graph_graph_time_control(bool enable) { }
824 #endif
825 
826 extern enum print_line_t
827 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
828 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
829 extern void
830 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
831 extern void graph_trace_open(struct trace_iterator *iter);
832 extern void graph_trace_close(struct trace_iterator *iter);
833 extern int __trace_graph_entry(struct trace_array *tr,
834 			       struct ftrace_graph_ent *trace,
835 			       unsigned int trace_ctx);
836 extern void __trace_graph_return(struct trace_array *tr,
837 				 struct ftrace_graph_ret *trace,
838 				 unsigned int trace_ctx);
839 
840 #ifdef CONFIG_DYNAMIC_FTRACE
841 extern struct ftrace_hash __rcu *ftrace_graph_hash;
842 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
843 
844 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
845 {
846 	unsigned long addr = trace->func;
847 	int ret = 0;
848 	struct ftrace_hash *hash;
849 
850 	preempt_disable_notrace();
851 
852 	/*
853 	 * Have to open code "rcu_dereference_sched()" because the
854 	 * function graph tracer can be called when RCU is not
855 	 * "watching".
856 	 * Protected with schedule_on_each_cpu(ftrace_sync)
857 	 */
858 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
859 
860 	if (ftrace_hash_empty(hash)) {
861 		ret = 1;
862 		goto out;
863 	}
864 
865 	if (ftrace_lookup_ip(hash, addr)) {
866 
867 		/*
868 		 * This needs to be cleared on the return functions
869 		 * when the depth is zero.
870 		 */
871 		trace_recursion_set(TRACE_GRAPH_BIT);
872 		trace_recursion_set_depth(trace->depth);
873 
874 		/*
875 		 * If no irqs are to be traced, but a set_graph_function
876 		 * is set, and called by an interrupt handler, we still
877 		 * want to trace it.
878 		 */
879 		if (in_irq())
880 			trace_recursion_set(TRACE_IRQ_BIT);
881 		else
882 			trace_recursion_clear(TRACE_IRQ_BIT);
883 		ret = 1;
884 	}
885 
886 out:
887 	preempt_enable_notrace();
888 	return ret;
889 }
890 
891 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
892 {
893 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
894 	    trace->depth == trace_recursion_depth())
895 		trace_recursion_clear(TRACE_GRAPH_BIT);
896 }
897 
898 static inline int ftrace_graph_notrace_addr(unsigned long addr)
899 {
900 	int ret = 0;
901 	struct ftrace_hash *notrace_hash;
902 
903 	preempt_disable_notrace();
904 
905 	/*
906 	 * Have to open code "rcu_dereference_sched()" because the
907 	 * function graph tracer can be called when RCU is not
908 	 * "watching".
909 	 * Protected with schedule_on_each_cpu(ftrace_sync)
910 	 */
911 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
912 						 !preemptible());
913 
914 	if (ftrace_lookup_ip(notrace_hash, addr))
915 		ret = 1;
916 
917 	preempt_enable_notrace();
918 	return ret;
919 }
920 #else
921 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
922 {
923 	return 1;
924 }
925 
926 static inline int ftrace_graph_notrace_addr(unsigned long addr)
927 {
928 	return 0;
929 }
930 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
931 { }
932 #endif /* CONFIG_DYNAMIC_FTRACE */
933 
934 extern unsigned int fgraph_max_depth;
935 
936 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
937 {
938 	/* trace it when it is-nested-in or is a function enabled. */
939 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
940 		 ftrace_graph_addr(trace)) ||
941 		(trace->depth < 0) ||
942 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
943 }
944 
945 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
946 static inline enum print_line_t
947 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
948 {
949 	return TRACE_TYPE_UNHANDLED;
950 }
951 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
952 
953 extern struct list_head ftrace_pids;
954 
955 #ifdef CONFIG_FUNCTION_TRACER
956 
957 #define FTRACE_PID_IGNORE	-1
958 #define FTRACE_PID_TRACE	-2
959 
960 struct ftrace_func_command {
961 	struct list_head	list;
962 	char			*name;
963 	int			(*func)(struct trace_array *tr,
964 					struct ftrace_hash *hash,
965 					char *func, char *cmd,
966 					char *params, int enable);
967 };
968 extern bool ftrace_filter_param __initdata;
969 static inline int ftrace_trace_task(struct trace_array *tr)
970 {
971 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
972 		FTRACE_PID_IGNORE;
973 }
974 extern int ftrace_is_dead(void);
975 int ftrace_create_function_files(struct trace_array *tr,
976 				 struct dentry *parent);
977 void ftrace_destroy_function_files(struct trace_array *tr);
978 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
979 void ftrace_free_ftrace_ops(struct trace_array *tr);
980 void ftrace_init_global_array_ops(struct trace_array *tr);
981 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
982 void ftrace_reset_array_ops(struct trace_array *tr);
983 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
984 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
985 				  struct dentry *d_tracer);
986 void ftrace_clear_pids(struct trace_array *tr);
987 int init_function_trace(void);
988 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
989 #else
990 static inline int ftrace_trace_task(struct trace_array *tr)
991 {
992 	return 1;
993 }
994 static inline int ftrace_is_dead(void) { return 0; }
995 static inline int
996 ftrace_create_function_files(struct trace_array *tr,
997 			     struct dentry *parent)
998 {
999 	return 0;
1000 }
1001 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1002 {
1003 	return 0;
1004 }
1005 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1006 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1007 static inline __init void
1008 ftrace_init_global_array_ops(struct trace_array *tr) { }
1009 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1010 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1011 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1012 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1013 static inline int init_function_trace(void) { return 0; }
1014 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1015 /* ftace_func_t type is not defined, use macro instead of static inline */
1016 #define ftrace_init_array_ops(tr, func) do { } while (0)
1017 #endif /* CONFIG_FUNCTION_TRACER */
1018 
1019 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1020 
1021 struct ftrace_probe_ops {
1022 	void			(*func)(unsigned long ip,
1023 					unsigned long parent_ip,
1024 					struct trace_array *tr,
1025 					struct ftrace_probe_ops *ops,
1026 					void *data);
1027 	int			(*init)(struct ftrace_probe_ops *ops,
1028 					struct trace_array *tr,
1029 					unsigned long ip, void *init_data,
1030 					void **data);
1031 	void			(*free)(struct ftrace_probe_ops *ops,
1032 					struct trace_array *tr,
1033 					unsigned long ip, void *data);
1034 	int			(*print)(struct seq_file *m,
1035 					 unsigned long ip,
1036 					 struct ftrace_probe_ops *ops,
1037 					 void *data);
1038 };
1039 
1040 struct ftrace_func_mapper;
1041 typedef int (*ftrace_mapper_func)(void *data);
1042 
1043 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1044 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1045 					   unsigned long ip);
1046 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1047 			       unsigned long ip, void *data);
1048 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1049 				   unsigned long ip);
1050 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1051 			     ftrace_mapper_func free_func);
1052 
1053 extern int
1054 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1055 			       struct ftrace_probe_ops *ops, void *data);
1056 extern int
1057 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1058 				      struct ftrace_probe_ops *ops);
1059 extern void clear_ftrace_function_probes(struct trace_array *tr);
1060 
1061 int register_ftrace_command(struct ftrace_func_command *cmd);
1062 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1063 
1064 void ftrace_create_filter_files(struct ftrace_ops *ops,
1065 				struct dentry *parent);
1066 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1067 
1068 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1069 			     int len, int reset);
1070 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1071 			      int len, int reset);
1072 #else
1073 struct ftrace_func_command;
1074 
1075 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1076 {
1077 	return -EINVAL;
1078 }
1079 static inline __init int unregister_ftrace_command(char *cmd_name)
1080 {
1081 	return -EINVAL;
1082 }
1083 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1084 {
1085 }
1086 
1087 /*
1088  * The ops parameter passed in is usually undefined.
1089  * This must be a macro.
1090  */
1091 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1092 #define ftrace_destroy_filter_files(ops) do { } while (0)
1093 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1094 
1095 bool ftrace_event_is_function(struct trace_event_call *call);
1096 
1097 /*
1098  * struct trace_parser - servers for reading the user input separated by spaces
1099  * @cont: set if the input is not complete - no final space char was found
1100  * @buffer: holds the parsed user input
1101  * @idx: user input length
1102  * @size: buffer size
1103  */
1104 struct trace_parser {
1105 	bool		cont;
1106 	char		*buffer;
1107 	unsigned	idx;
1108 	unsigned	size;
1109 };
1110 
1111 static inline bool trace_parser_loaded(struct trace_parser *parser)
1112 {
1113 	return (parser->idx != 0);
1114 }
1115 
1116 static inline bool trace_parser_cont(struct trace_parser *parser)
1117 {
1118 	return parser->cont;
1119 }
1120 
1121 static inline void trace_parser_clear(struct trace_parser *parser)
1122 {
1123 	parser->cont = false;
1124 	parser->idx = 0;
1125 }
1126 
1127 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1128 extern void trace_parser_put(struct trace_parser *parser);
1129 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1130 	size_t cnt, loff_t *ppos);
1131 
1132 /*
1133  * Only create function graph options if function graph is configured.
1134  */
1135 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1136 # define FGRAPH_FLAGS						\
1137 		C(DISPLAY_GRAPH,	"display-graph"),
1138 #else
1139 # define FGRAPH_FLAGS
1140 #endif
1141 
1142 #ifdef CONFIG_BRANCH_TRACER
1143 # define BRANCH_FLAGS					\
1144 		C(BRANCH,		"branch"),
1145 #else
1146 # define BRANCH_FLAGS
1147 #endif
1148 
1149 #ifdef CONFIG_FUNCTION_TRACER
1150 # define FUNCTION_FLAGS						\
1151 		C(FUNCTION,		"function-trace"),	\
1152 		C(FUNC_FORK,		"function-fork"),
1153 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1154 #else
1155 # define FUNCTION_FLAGS
1156 # define FUNCTION_DEFAULT_FLAGS		0UL
1157 # define TRACE_ITER_FUNC_FORK		0UL
1158 #endif
1159 
1160 #ifdef CONFIG_STACKTRACE
1161 # define STACK_FLAGS				\
1162 		C(STACKTRACE,		"stacktrace"),
1163 #else
1164 # define STACK_FLAGS
1165 #endif
1166 
1167 /*
1168  * trace_iterator_flags is an enumeration that defines bit
1169  * positions into trace_flags that controls the output.
1170  *
1171  * NOTE: These bits must match the trace_options array in
1172  *       trace.c (this macro guarantees it).
1173  */
1174 #define TRACE_FLAGS						\
1175 		C(PRINT_PARENT,		"print-parent"),	\
1176 		C(SYM_OFFSET,		"sym-offset"),		\
1177 		C(SYM_ADDR,		"sym-addr"),		\
1178 		C(VERBOSE,		"verbose"),		\
1179 		C(RAW,			"raw"),			\
1180 		C(HEX,			"hex"),			\
1181 		C(BIN,			"bin"),			\
1182 		C(BLOCK,		"block"),		\
1183 		C(PRINTK,		"trace_printk"),	\
1184 		C(ANNOTATE,		"annotate"),		\
1185 		C(USERSTACKTRACE,	"userstacktrace"),	\
1186 		C(SYM_USEROBJ,		"sym-userobj"),		\
1187 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1188 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1189 		C(LATENCY_FMT,		"latency-format"),	\
1190 		C(RECORD_CMD,		"record-cmd"),		\
1191 		C(RECORD_TGID,		"record-tgid"),		\
1192 		C(OVERWRITE,		"overwrite"),		\
1193 		C(STOP_ON_FREE,		"disable_on_free"),	\
1194 		C(IRQ_INFO,		"irq-info"),		\
1195 		C(MARKERS,		"markers"),		\
1196 		C(EVENT_FORK,		"event-fork"),		\
1197 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1198 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1199 		FUNCTION_FLAGS					\
1200 		FGRAPH_FLAGS					\
1201 		STACK_FLAGS					\
1202 		BRANCH_FLAGS
1203 
1204 /*
1205  * By defining C, we can make TRACE_FLAGS a list of bit names
1206  * that will define the bits for the flag masks.
1207  */
1208 #undef C
1209 #define C(a, b) TRACE_ITER_##a##_BIT
1210 
1211 enum trace_iterator_bits {
1212 	TRACE_FLAGS
1213 	/* Make sure we don't go more than we have bits for */
1214 	TRACE_ITER_LAST_BIT
1215 };
1216 
1217 /*
1218  * By redefining C, we can make TRACE_FLAGS a list of masks that
1219  * use the bits as defined above.
1220  */
1221 #undef C
1222 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1223 
1224 enum trace_iterator_flags { TRACE_FLAGS };
1225 
1226 /*
1227  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1228  * control the output of kernel symbols.
1229  */
1230 #define TRACE_ITER_SYM_MASK \
1231 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1232 
1233 extern struct tracer nop_trace;
1234 
1235 #ifdef CONFIG_BRANCH_TRACER
1236 extern int enable_branch_tracing(struct trace_array *tr);
1237 extern void disable_branch_tracing(void);
1238 static inline int trace_branch_enable(struct trace_array *tr)
1239 {
1240 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1241 		return enable_branch_tracing(tr);
1242 	return 0;
1243 }
1244 static inline void trace_branch_disable(void)
1245 {
1246 	/* due to races, always disable */
1247 	disable_branch_tracing();
1248 }
1249 #else
1250 static inline int trace_branch_enable(struct trace_array *tr)
1251 {
1252 	return 0;
1253 }
1254 static inline void trace_branch_disable(void)
1255 {
1256 }
1257 #endif /* CONFIG_BRANCH_TRACER */
1258 
1259 /* set ring buffers to default size if not already done so */
1260 int tracing_update_buffers(void);
1261 
1262 struct ftrace_event_field {
1263 	struct list_head	link;
1264 	const char		*name;
1265 	const char		*type;
1266 	int			filter_type;
1267 	int			offset;
1268 	int			size;
1269 	int			is_signed;
1270 };
1271 
1272 struct prog_entry;
1273 
1274 struct event_filter {
1275 	struct prog_entry __rcu	*prog;
1276 	char			*filter_string;
1277 };
1278 
1279 struct event_subsystem {
1280 	struct list_head	list;
1281 	const char		*name;
1282 	struct event_filter	*filter;
1283 	int			ref_count;
1284 };
1285 
1286 struct trace_subsystem_dir {
1287 	struct list_head		list;
1288 	struct event_subsystem		*subsystem;
1289 	struct trace_array		*tr;
1290 	struct dentry			*entry;
1291 	int				ref_count;
1292 	int				nr_events;
1293 };
1294 
1295 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1296 				     struct trace_buffer *buffer,
1297 				     struct ring_buffer_event *event);
1298 
1299 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1300 				     struct trace_buffer *buffer,
1301 				     struct ring_buffer_event *event,
1302 				     unsigned int trcace_ctx,
1303 				     struct pt_regs *regs);
1304 
1305 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1306 					      struct trace_buffer *buffer,
1307 					      struct ring_buffer_event *event,
1308 					      unsigned int trace_ctx)
1309 {
1310 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1311 }
1312 
1313 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1314 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1315 void trace_buffered_event_disable(void);
1316 void trace_buffered_event_enable(void);
1317 
1318 static inline void
1319 __trace_event_discard_commit(struct trace_buffer *buffer,
1320 			     struct ring_buffer_event *event)
1321 {
1322 	if (this_cpu_read(trace_buffered_event) == event) {
1323 		/* Simply release the temp buffer */
1324 		this_cpu_dec(trace_buffered_event_cnt);
1325 		return;
1326 	}
1327 	ring_buffer_discard_commit(buffer, event);
1328 }
1329 
1330 /*
1331  * Helper function for event_trigger_unlock_commit{_regs}().
1332  * If there are event triggers attached to this event that requires
1333  * filtering against its fields, then they will be called as the
1334  * entry already holds the field information of the current event.
1335  *
1336  * It also checks if the event should be discarded or not.
1337  * It is to be discarded if the event is soft disabled and the
1338  * event was only recorded to process triggers, or if the event
1339  * filter is active and this event did not match the filters.
1340  *
1341  * Returns true if the event is discarded, false otherwise.
1342  */
1343 static inline bool
1344 __event_trigger_test_discard(struct trace_event_file *file,
1345 			     struct trace_buffer *buffer,
1346 			     struct ring_buffer_event *event,
1347 			     void *entry,
1348 			     enum event_trigger_type *tt)
1349 {
1350 	unsigned long eflags = file->flags;
1351 
1352 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1353 		*tt = event_triggers_call(file, buffer, entry, event);
1354 
1355 	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1356 	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1357 	     !filter_match_preds(file->filter, entry))) {
1358 		__trace_event_discard_commit(buffer, event);
1359 		return true;
1360 	}
1361 
1362 	return false;
1363 }
1364 
1365 /**
1366  * event_trigger_unlock_commit - handle triggers and finish event commit
1367  * @file: The file pointer associated with the event
1368  * @buffer: The ring buffer that the event is being written to
1369  * @event: The event meta data in the ring buffer
1370  * @entry: The event itself
1371  * @trace_ctx: The tracing context flags.
1372  *
1373  * This is a helper function to handle triggers that require data
1374  * from the event itself. It also tests the event against filters and
1375  * if the event is soft disabled and should be discarded.
1376  */
1377 static inline void
1378 event_trigger_unlock_commit(struct trace_event_file *file,
1379 			    struct trace_buffer *buffer,
1380 			    struct ring_buffer_event *event,
1381 			    void *entry, unsigned int trace_ctx)
1382 {
1383 	enum event_trigger_type tt = ETT_NONE;
1384 
1385 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1386 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1387 
1388 	if (tt)
1389 		event_triggers_post_call(file, tt);
1390 }
1391 
1392 #define FILTER_PRED_INVALID	((unsigned short)-1)
1393 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1394 #define FILTER_PRED_FOLD	(1 << 15)
1395 
1396 /*
1397  * The max preds is the size of unsigned short with
1398  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1399  * and FOLD flags. The other is reserved.
1400  *
1401  * 2^14 preds is way more than enough.
1402  */
1403 #define MAX_FILTER_PRED		16384
1404 
1405 struct filter_pred;
1406 struct regex;
1407 
1408 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1409 
1410 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1411 
1412 enum regex_type {
1413 	MATCH_FULL = 0,
1414 	MATCH_FRONT_ONLY,
1415 	MATCH_MIDDLE_ONLY,
1416 	MATCH_END_ONLY,
1417 	MATCH_GLOB,
1418 	MATCH_INDEX,
1419 };
1420 
1421 struct regex {
1422 	char			pattern[MAX_FILTER_STR_VAL];
1423 	int			len;
1424 	int			field_len;
1425 	regex_match_func	match;
1426 };
1427 
1428 struct filter_pred {
1429 	filter_pred_fn_t 	fn;
1430 	u64 			val;
1431 	struct regex		regex;
1432 	unsigned short		*ops;
1433 	struct ftrace_event_field *field;
1434 	int 			offset;
1435 	int			not;
1436 	int 			op;
1437 };
1438 
1439 static inline bool is_string_field(struct ftrace_event_field *field)
1440 {
1441 	return field->filter_type == FILTER_DYN_STRING ||
1442 	       field->filter_type == FILTER_STATIC_STRING ||
1443 	       field->filter_type == FILTER_PTR_STRING ||
1444 	       field->filter_type == FILTER_COMM;
1445 }
1446 
1447 static inline bool is_function_field(struct ftrace_event_field *field)
1448 {
1449 	return field->filter_type == FILTER_TRACE_FN;
1450 }
1451 
1452 extern enum regex_type
1453 filter_parse_regex(char *buff, int len, char **search, int *not);
1454 extern void print_event_filter(struct trace_event_file *file,
1455 			       struct trace_seq *s);
1456 extern int apply_event_filter(struct trace_event_file *file,
1457 			      char *filter_string);
1458 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1459 					char *filter_string);
1460 extern void print_subsystem_event_filter(struct event_subsystem *system,
1461 					 struct trace_seq *s);
1462 extern int filter_assign_type(const char *type);
1463 extern int create_event_filter(struct trace_array *tr,
1464 			       struct trace_event_call *call,
1465 			       char *filter_str, bool set_str,
1466 			       struct event_filter **filterp);
1467 extern void free_event_filter(struct event_filter *filter);
1468 
1469 struct ftrace_event_field *
1470 trace_find_event_field(struct trace_event_call *call, char *name);
1471 
1472 extern void trace_event_enable_cmd_record(bool enable);
1473 extern void trace_event_enable_tgid_record(bool enable);
1474 
1475 extern int event_trace_init(void);
1476 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1477 extern int event_trace_del_tracer(struct trace_array *tr);
1478 extern void __trace_early_add_events(struct trace_array *tr);
1479 
1480 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1481 						  const char *system,
1482 						  const char *event);
1483 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1484 						const char *system,
1485 						const char *event);
1486 
1487 static inline void *event_file_data(struct file *filp)
1488 {
1489 	return READ_ONCE(file_inode(filp)->i_private);
1490 }
1491 
1492 extern struct mutex event_mutex;
1493 extern struct list_head ftrace_events;
1494 
1495 extern const struct file_operations event_trigger_fops;
1496 extern const struct file_operations event_hist_fops;
1497 extern const struct file_operations event_hist_debug_fops;
1498 extern const struct file_operations event_inject_fops;
1499 
1500 #ifdef CONFIG_HIST_TRIGGERS
1501 extern int register_trigger_hist_cmd(void);
1502 extern int register_trigger_hist_enable_disable_cmds(void);
1503 #else
1504 static inline int register_trigger_hist_cmd(void) { return 0; }
1505 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1506 #endif
1507 
1508 extern int register_trigger_cmds(void);
1509 extern void clear_event_triggers(struct trace_array *tr);
1510 
1511 struct event_trigger_data {
1512 	unsigned long			count;
1513 	int				ref;
1514 	struct event_trigger_ops	*ops;
1515 	struct event_command		*cmd_ops;
1516 	struct event_filter __rcu	*filter;
1517 	char				*filter_str;
1518 	void				*private_data;
1519 	bool				paused;
1520 	bool				paused_tmp;
1521 	struct list_head		list;
1522 	char				*name;
1523 	struct list_head		named_list;
1524 	struct event_trigger_data	*named_data;
1525 };
1526 
1527 /* Avoid typos */
1528 #define ENABLE_EVENT_STR	"enable_event"
1529 #define DISABLE_EVENT_STR	"disable_event"
1530 #define ENABLE_HIST_STR		"enable_hist"
1531 #define DISABLE_HIST_STR	"disable_hist"
1532 
1533 struct enable_trigger_data {
1534 	struct trace_event_file		*file;
1535 	bool				enable;
1536 	bool				hist;
1537 };
1538 
1539 extern int event_enable_trigger_print(struct seq_file *m,
1540 				      struct event_trigger_ops *ops,
1541 				      struct event_trigger_data *data);
1542 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1543 				      struct event_trigger_data *data);
1544 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1545 				     struct trace_event_file *file,
1546 				     char *glob, char *cmd, char *param);
1547 extern int event_enable_register_trigger(char *glob,
1548 					 struct event_trigger_ops *ops,
1549 					 struct event_trigger_data *data,
1550 					 struct trace_event_file *file);
1551 extern void event_enable_unregister_trigger(char *glob,
1552 					    struct event_trigger_ops *ops,
1553 					    struct event_trigger_data *test,
1554 					    struct trace_event_file *file);
1555 extern void trigger_data_free(struct event_trigger_data *data);
1556 extern int event_trigger_init(struct event_trigger_ops *ops,
1557 			      struct event_trigger_data *data);
1558 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1559 					      int trigger_enable);
1560 extern void update_cond_flag(struct trace_event_file *file);
1561 extern int set_trigger_filter(char *filter_str,
1562 			      struct event_trigger_data *trigger_data,
1563 			      struct trace_event_file *file);
1564 extern struct event_trigger_data *find_named_trigger(const char *name);
1565 extern bool is_named_trigger(struct event_trigger_data *test);
1566 extern int save_named_trigger(const char *name,
1567 			      struct event_trigger_data *data);
1568 extern void del_named_trigger(struct event_trigger_data *data);
1569 extern void pause_named_trigger(struct event_trigger_data *data);
1570 extern void unpause_named_trigger(struct event_trigger_data *data);
1571 extern void set_named_trigger_data(struct event_trigger_data *data,
1572 				   struct event_trigger_data *named_data);
1573 extern struct event_trigger_data *
1574 get_named_trigger_data(struct event_trigger_data *data);
1575 extern int register_event_command(struct event_command *cmd);
1576 extern int unregister_event_command(struct event_command *cmd);
1577 extern int register_trigger_hist_enable_disable_cmds(void);
1578 
1579 /**
1580  * struct event_trigger_ops - callbacks for trace event triggers
1581  *
1582  * The methods in this structure provide per-event trigger hooks for
1583  * various trigger operations.
1584  *
1585  * All the methods below, except for @init() and @free(), must be
1586  * implemented.
1587  *
1588  * @func: The trigger 'probe' function called when the triggering
1589  *	event occurs.  The data passed into this callback is the data
1590  *	that was supplied to the event_command @reg() function that
1591  *	registered the trigger (see struct event_command) along with
1592  *	the trace record, rec.
1593  *
1594  * @init: An optional initialization function called for the trigger
1595  *	when the trigger is registered (via the event_command reg()
1596  *	function).  This can be used to perform per-trigger
1597  *	initialization such as incrementing a per-trigger reference
1598  *	count, for instance.  This is usually implemented by the
1599  *	generic utility function @event_trigger_init() (see
1600  *	trace_event_triggers.c).
1601  *
1602  * @free: An optional de-initialization function called for the
1603  *	trigger when the trigger is unregistered (via the
1604  *	event_command @reg() function).  This can be used to perform
1605  *	per-trigger de-initialization such as decrementing a
1606  *	per-trigger reference count and freeing corresponding trigger
1607  *	data, for instance.  This is usually implemented by the
1608  *	generic utility function @event_trigger_free() (see
1609  *	trace_event_triggers.c).
1610  *
1611  * @print: The callback function invoked to have the trigger print
1612  *	itself.  This is usually implemented by a wrapper function
1613  *	that calls the generic utility function @event_trigger_print()
1614  *	(see trace_event_triggers.c).
1615  */
1616 struct event_trigger_ops {
1617 	void			(*func)(struct event_trigger_data *data,
1618 					struct trace_buffer *buffer, void *rec,
1619 					struct ring_buffer_event *rbe);
1620 	int			(*init)(struct event_trigger_ops *ops,
1621 					struct event_trigger_data *data);
1622 	void			(*free)(struct event_trigger_ops *ops,
1623 					struct event_trigger_data *data);
1624 	int			(*print)(struct seq_file *m,
1625 					 struct event_trigger_ops *ops,
1626 					 struct event_trigger_data *data);
1627 };
1628 
1629 /**
1630  * struct event_command - callbacks and data members for event commands
1631  *
1632  * Event commands are invoked by users by writing the command name
1633  * into the 'trigger' file associated with a trace event.  The
1634  * parameters associated with a specific invocation of an event
1635  * command are used to create an event trigger instance, which is
1636  * added to the list of trigger instances associated with that trace
1637  * event.  When the event is hit, the set of triggers associated with
1638  * that event is invoked.
1639  *
1640  * The data members in this structure provide per-event command data
1641  * for various event commands.
1642  *
1643  * All the data members below, except for @post_trigger, must be set
1644  * for each event command.
1645  *
1646  * @name: The unique name that identifies the event command.  This is
1647  *	the name used when setting triggers via trigger files.
1648  *
1649  * @trigger_type: A unique id that identifies the event command
1650  *	'type'.  This value has two purposes, the first to ensure that
1651  *	only one trigger of the same type can be set at a given time
1652  *	for a particular event e.g. it doesn't make sense to have both
1653  *	a traceon and traceoff trigger attached to a single event at
1654  *	the same time, so traceon and traceoff have the same type
1655  *	though they have different names.  The @trigger_type value is
1656  *	also used as a bit value for deferring the actual trigger
1657  *	action until after the current event is finished.  Some
1658  *	commands need to do this if they themselves log to the trace
1659  *	buffer (see the @post_trigger() member below).  @trigger_type
1660  *	values are defined by adding new values to the trigger_type
1661  *	enum in include/linux/trace_events.h.
1662  *
1663  * @flags: See the enum event_command_flags below.
1664  *
1665  * All the methods below, except for @set_filter() and @unreg_all(),
1666  * must be implemented.
1667  *
1668  * @func: The callback function responsible for parsing and
1669  *	registering the trigger written to the 'trigger' file by the
1670  *	user.  It allocates the trigger instance and registers it with
1671  *	the appropriate trace event.  It makes use of the other
1672  *	event_command callback functions to orchestrate this, and is
1673  *	usually implemented by the generic utility function
1674  *	@event_trigger_callback() (see trace_event_triggers.c).
1675  *
1676  * @reg: Adds the trigger to the list of triggers associated with the
1677  *	event, and enables the event trigger itself, after
1678  *	initializing it (via the event_trigger_ops @init() function).
1679  *	This is also where commands can use the @trigger_type value to
1680  *	make the decision as to whether or not multiple instances of
1681  *	the trigger should be allowed.  This is usually implemented by
1682  *	the generic utility function @register_trigger() (see
1683  *	trace_event_triggers.c).
1684  *
1685  * @unreg: Removes the trigger from the list of triggers associated
1686  *	with the event, and disables the event trigger itself, after
1687  *	initializing it (via the event_trigger_ops @free() function).
1688  *	This is usually implemented by the generic utility function
1689  *	@unregister_trigger() (see trace_event_triggers.c).
1690  *
1691  * @unreg_all: An optional function called to remove all the triggers
1692  *	from the list of triggers associated with the event.  Called
1693  *	when a trigger file is opened in truncate mode.
1694  *
1695  * @set_filter: An optional function called to parse and set a filter
1696  *	for the trigger.  If no @set_filter() method is set for the
1697  *	event command, filters set by the user for the command will be
1698  *	ignored.  This is usually implemented by the generic utility
1699  *	function @set_trigger_filter() (see trace_event_triggers.c).
1700  *
1701  * @get_trigger_ops: The callback function invoked to retrieve the
1702  *	event_trigger_ops implementation associated with the command.
1703  */
1704 struct event_command {
1705 	struct list_head	list;
1706 	char			*name;
1707 	enum event_trigger_type	trigger_type;
1708 	int			flags;
1709 	int			(*func)(struct event_command *cmd_ops,
1710 					struct trace_event_file *file,
1711 					char *glob, char *cmd, char *params);
1712 	int			(*reg)(char *glob,
1713 				       struct event_trigger_ops *ops,
1714 				       struct event_trigger_data *data,
1715 				       struct trace_event_file *file);
1716 	void			(*unreg)(char *glob,
1717 					 struct event_trigger_ops *ops,
1718 					 struct event_trigger_data *data,
1719 					 struct trace_event_file *file);
1720 	void			(*unreg_all)(struct trace_event_file *file);
1721 	int			(*set_filter)(char *filter_str,
1722 					      struct event_trigger_data *data,
1723 					      struct trace_event_file *file);
1724 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1725 };
1726 
1727 /**
1728  * enum event_command_flags - flags for struct event_command
1729  *
1730  * @POST_TRIGGER: A flag that says whether or not this command needs
1731  *	to have its action delayed until after the current event has
1732  *	been closed.  Some triggers need to avoid being invoked while
1733  *	an event is currently in the process of being logged, since
1734  *	the trigger may itself log data into the trace buffer.  Thus
1735  *	we make sure the current event is committed before invoking
1736  *	those triggers.  To do that, the trigger invocation is split
1737  *	in two - the first part checks the filter using the current
1738  *	trace record; if a command has the @post_trigger flag set, it
1739  *	sets a bit for itself in the return value, otherwise it
1740  *	directly invokes the trigger.  Once all commands have been
1741  *	either invoked or set their return flag, the current record is
1742  *	either committed or discarded.  At that point, if any commands
1743  *	have deferred their triggers, those commands are finally
1744  *	invoked following the close of the current event.  In other
1745  *	words, if the event_trigger_ops @func() probe implementation
1746  *	itself logs to the trace buffer, this flag should be set,
1747  *	otherwise it can be left unspecified.
1748  *
1749  * @NEEDS_REC: A flag that says whether or not this command needs
1750  *	access to the trace record in order to perform its function,
1751  *	regardless of whether or not it has a filter associated with
1752  *	it (filters make a trigger require access to the trace record
1753  *	but are not always present).
1754  */
1755 enum event_command_flags {
1756 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1757 	EVENT_CMD_FL_NEEDS_REC		= 2,
1758 };
1759 
1760 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1761 {
1762 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1763 }
1764 
1765 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1766 {
1767 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1768 }
1769 
1770 extern int trace_event_enable_disable(struct trace_event_file *file,
1771 				      int enable, int soft_disable);
1772 extern int tracing_alloc_snapshot(void);
1773 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1774 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1775 
1776 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1777 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1778 
1779 extern const char *__start___trace_bprintk_fmt[];
1780 extern const char *__stop___trace_bprintk_fmt[];
1781 
1782 extern const char *__start___tracepoint_str[];
1783 extern const char *__stop___tracepoint_str[];
1784 
1785 void trace_printk_control(bool enabled);
1786 void trace_printk_start_comm(void);
1787 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1788 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1789 
1790 /* Used from boot time tracer */
1791 extern int trace_set_options(struct trace_array *tr, char *option);
1792 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1793 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1794 					  unsigned long size, int cpu_id);
1795 extern int tracing_set_cpumask(struct trace_array *tr,
1796 				cpumask_var_t tracing_cpumask_new);
1797 
1798 
1799 #define MAX_EVENT_NAME_LEN	64
1800 
1801 extern ssize_t trace_parse_run_command(struct file *file,
1802 		const char __user *buffer, size_t count, loff_t *ppos,
1803 		int (*createfn)(const char *));
1804 
1805 extern unsigned int err_pos(char *cmd, const char *str);
1806 extern void tracing_log_err(struct trace_array *tr,
1807 			    const char *loc, const char *cmd,
1808 			    const char **errs, u8 type, u8 pos);
1809 
1810 /*
1811  * Normal trace_printk() and friends allocates special buffers
1812  * to do the manipulation, as well as saves the print formats
1813  * into sections to display. But the trace infrastructure wants
1814  * to use these without the added overhead at the price of being
1815  * a bit slower (used mainly for warnings, where we don't care
1816  * about performance). The internal_trace_puts() is for such
1817  * a purpose.
1818  */
1819 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1820 
1821 #undef FTRACE_ENTRY
1822 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1823 	extern struct trace_event_call					\
1824 	__aligned(4) event_##call;
1825 #undef FTRACE_ENTRY_DUP
1826 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1827 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1828 #undef FTRACE_ENTRY_PACKED
1829 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1830 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1831 
1832 #include "trace_entries.h"
1833 
1834 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1835 int perf_ftrace_event_register(struct trace_event_call *call,
1836 			       enum trace_reg type, void *data);
1837 #else
1838 #define perf_ftrace_event_register NULL
1839 #endif
1840 
1841 #ifdef CONFIG_FTRACE_SYSCALLS
1842 void init_ftrace_syscalls(void);
1843 const char *get_syscall_name(int syscall);
1844 #else
1845 static inline void init_ftrace_syscalls(void) { }
1846 static inline const char *get_syscall_name(int syscall)
1847 {
1848 	return NULL;
1849 }
1850 #endif
1851 
1852 #ifdef CONFIG_EVENT_TRACING
1853 void trace_event_init(void);
1854 void trace_event_eval_update(struct trace_eval_map **map, int len);
1855 /* Used from boot time tracer */
1856 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1857 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1858 #else
1859 static inline void __init trace_event_init(void) { }
1860 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1861 #endif
1862 
1863 #ifdef CONFIG_TRACER_SNAPSHOT
1864 void tracing_snapshot_instance(struct trace_array *tr);
1865 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1866 #else
1867 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1868 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1869 {
1870 	return 0;
1871 }
1872 #endif
1873 
1874 #ifdef CONFIG_PREEMPT_TRACER
1875 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1876 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1877 #else
1878 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1879 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1880 #endif
1881 #ifdef CONFIG_IRQSOFF_TRACER
1882 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1883 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1884 #else
1885 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1886 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1887 #endif
1888 
1889 extern struct trace_iterator *tracepoint_print_iter;
1890 
1891 /*
1892  * Reset the state of the trace_iterator so that it can read consumed data.
1893  * Normally, the trace_iterator is used for reading the data when it is not
1894  * consumed, and must retain state.
1895  */
1896 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1897 {
1898 	const size_t offset = offsetof(struct trace_iterator, seq);
1899 
1900 	/*
1901 	 * Keep gcc from complaining about overwriting more than just one
1902 	 * member in the structure.
1903 	 */
1904 	memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1905 
1906 	iter->pos = -1;
1907 }
1908 
1909 /* Check the name is good for event/group/fields */
1910 static inline bool is_good_name(const char *name)
1911 {
1912 	if (!isalpha(*name) && *name != '_')
1913 		return false;
1914 	while (*++name != '\0') {
1915 		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1916 			return false;
1917 	}
1918 	return true;
1919 }
1920 
1921 /*
1922  * This is a generic way to read and write a u64 value from a file in tracefs.
1923  *
1924  * The value is stored on the variable pointed by *val. The value needs
1925  * to be at least *min and at most *max. The write is protected by an
1926  * existing *lock.
1927  */
1928 struct trace_min_max_param {
1929 	struct mutex	*lock;
1930 	u64		*val;
1931 	u64		*min;
1932 	u64		*max;
1933 };
1934 
1935 #define U64_STR_SIZE		24	/* 20 digits max */
1936 
1937 extern const struct file_operations trace_min_max_fops;
1938 
1939 #endif /* _LINUX_KERNEL_TRACE_H */
1940