xref: /openbmc/linux/kernel/trace/trace.h (revision 405db98b)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5 
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24 
25 #include "pid_list.h"
26 
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h>		/* For NR_SYSCALLS	     */
29 #include <asm/syscall.h>	/* some archs define it here */
30 #endif
31 
32 #define TRACE_MODE_WRITE	0640
33 #define TRACE_MODE_READ		0440
34 
35 enum trace_type {
36 	__TRACE_FIRST_TYPE = 0,
37 
38 	TRACE_FN,
39 	TRACE_CTX,
40 	TRACE_WAKE,
41 	TRACE_STACK,
42 	TRACE_PRINT,
43 	TRACE_BPRINT,
44 	TRACE_MMIO_RW,
45 	TRACE_MMIO_MAP,
46 	TRACE_BRANCH,
47 	TRACE_GRAPH_RET,
48 	TRACE_GRAPH_ENT,
49 	TRACE_USER_STACK,
50 	TRACE_BLK,
51 	TRACE_BPUTS,
52 	TRACE_HWLAT,
53 	TRACE_OSNOISE,
54 	TRACE_TIMERLAT,
55 	TRACE_RAW_DATA,
56 	TRACE_FUNC_REPEATS,
57 
58 	__TRACE_LAST_TYPE,
59 };
60 
61 
62 #undef __field
63 #define __field(type, item)		type	item;
64 
65 #undef __field_fn
66 #define __field_fn(type, item)		type	item;
67 
68 #undef __field_struct
69 #define __field_struct(type, item)	__field(type, item)
70 
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73 
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76 
77 #undef __array
78 #define __array(type, item, size)	type	item[size];
79 
80 #undef __array_desc
81 #define __array_desc(type, container, item, size)
82 
83 #undef __dynamic_array
84 #define __dynamic_array(type, item)	type	item[];
85 
86 #undef F_STRUCT
87 #define F_STRUCT(args...)		args
88 
89 #undef FTRACE_ENTRY
90 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
91 	struct struct_name {						\
92 		struct trace_entry	ent;				\
93 		tstruct							\
94 	}
95 
96 #undef FTRACE_ENTRY_DUP
97 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
98 
99 #undef FTRACE_ENTRY_REG
100 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
101 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
102 
103 #undef FTRACE_ENTRY_PACKED
104 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
105 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
106 
107 #include "trace_entries.h"
108 
109 /* Use this for memory failure errors */
110 #define MEM_FAIL(condition, fmt, ...)					\
111 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
112 
113 /*
114  * syscalls are special, and need special handling, this is why
115  * they are not included in trace_entries.h
116  */
117 struct syscall_trace_enter {
118 	struct trace_entry	ent;
119 	int			nr;
120 	unsigned long		args[];
121 };
122 
123 struct syscall_trace_exit {
124 	struct trace_entry	ent;
125 	int			nr;
126 	long			ret;
127 };
128 
129 struct kprobe_trace_entry_head {
130 	struct trace_entry	ent;
131 	unsigned long		ip;
132 };
133 
134 struct eprobe_trace_entry_head {
135 	struct trace_entry	ent;
136 	unsigned int		type;
137 };
138 
139 struct kretprobe_trace_entry_head {
140 	struct trace_entry	ent;
141 	unsigned long		func;
142 	unsigned long		ret_ip;
143 };
144 
145 #define TRACE_BUF_SIZE		1024
146 
147 struct trace_array;
148 
149 /*
150  * The CPU trace array - it consists of thousands of trace entries
151  * plus some other descriptor data: (for example which task started
152  * the trace, etc.)
153  */
154 struct trace_array_cpu {
155 	atomic_t		disabled;
156 	void			*buffer_page;	/* ring buffer spare */
157 
158 	unsigned long		entries;
159 	unsigned long		saved_latency;
160 	unsigned long		critical_start;
161 	unsigned long		critical_end;
162 	unsigned long		critical_sequence;
163 	unsigned long		nice;
164 	unsigned long		policy;
165 	unsigned long		rt_priority;
166 	unsigned long		skipped_entries;
167 	u64			preempt_timestamp;
168 	pid_t			pid;
169 	kuid_t			uid;
170 	char			comm[TASK_COMM_LEN];
171 
172 #ifdef CONFIG_FUNCTION_TRACER
173 	int			ftrace_ignore_pid;
174 #endif
175 	bool			ignore_pid;
176 };
177 
178 struct tracer;
179 struct trace_option_dentry;
180 
181 struct array_buffer {
182 	struct trace_array		*tr;
183 	struct trace_buffer		*buffer;
184 	struct trace_array_cpu __percpu	*data;
185 	u64				time_start;
186 	int				cpu;
187 };
188 
189 #define TRACE_FLAGS_MAX_SIZE		32
190 
191 struct trace_options {
192 	struct tracer			*tracer;
193 	struct trace_option_dentry	*topts;
194 };
195 
196 struct trace_pid_list *trace_pid_list_alloc(void);
197 void trace_pid_list_free(struct trace_pid_list *pid_list);
198 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
199 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
200 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
201 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
202 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
203 			unsigned int *next);
204 
205 enum {
206 	TRACE_PIDS		= BIT(0),
207 	TRACE_NO_PIDS		= BIT(1),
208 };
209 
210 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
211 				    struct trace_pid_list *no_pid_list)
212 {
213 	/* Return true if the pid list in type has pids */
214 	return ((type & TRACE_PIDS) && pid_list) ||
215 		((type & TRACE_NO_PIDS) && no_pid_list);
216 }
217 
218 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
219 					 struct trace_pid_list *no_pid_list)
220 {
221 	/*
222 	 * Turning off what is in @type, return true if the "other"
223 	 * pid list, still has pids in it.
224 	 */
225 	return (!(type & TRACE_PIDS) && pid_list) ||
226 		(!(type & TRACE_NO_PIDS) && no_pid_list);
227 }
228 
229 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
230 
231 /**
232  * struct cond_snapshot - conditional snapshot data and callback
233  *
234  * The cond_snapshot structure encapsulates a callback function and
235  * data associated with the snapshot for a given tracing instance.
236  *
237  * When a snapshot is taken conditionally, by invoking
238  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
239  * passed in turn to the cond_snapshot.update() function.  That data
240  * can be compared by the update() implementation with the cond_data
241  * contained within the struct cond_snapshot instance associated with
242  * the trace_array.  Because the tr->max_lock is held throughout the
243  * update() call, the update() function can directly retrieve the
244  * cond_snapshot and cond_data associated with the per-instance
245  * snapshot associated with the trace_array.
246  *
247  * The cond_snapshot.update() implementation can save data to be
248  * associated with the snapshot if it decides to, and returns 'true'
249  * in that case, or it returns 'false' if the conditional snapshot
250  * shouldn't be taken.
251  *
252  * The cond_snapshot instance is created and associated with the
253  * user-defined cond_data by tracing_cond_snapshot_enable().
254  * Likewise, the cond_snapshot instance is destroyed and is no longer
255  * associated with the trace instance by
256  * tracing_cond_snapshot_disable().
257  *
258  * The method below is required.
259  *
260  * @update: When a conditional snapshot is invoked, the update()
261  *	callback function is invoked with the tr->max_lock held.  The
262  *	update() implementation signals whether or not to actually
263  *	take the snapshot, by returning 'true' if so, 'false' if no
264  *	snapshot should be taken.  Because the max_lock is held for
265  *	the duration of update(), the implementation is safe to
266  *	directly retrieved and save any implementation data it needs
267  *	to in association with the snapshot.
268  */
269 struct cond_snapshot {
270 	void				*cond_data;
271 	cond_update_fn_t		update;
272 };
273 
274 /*
275  * struct trace_func_repeats - used to keep track of the consecutive
276  * (on the same CPU) calls of a single function.
277  */
278 struct trace_func_repeats {
279 	unsigned long	ip;
280 	unsigned long	parent_ip;
281 	unsigned long	count;
282 	u64		ts_last_call;
283 };
284 
285 /*
286  * The trace array - an array of per-CPU trace arrays. This is the
287  * highest level data structure that individual tracers deal with.
288  * They have on/off state as well:
289  */
290 struct trace_array {
291 	struct list_head	list;
292 	char			*name;
293 	struct array_buffer	array_buffer;
294 #ifdef CONFIG_TRACER_MAX_TRACE
295 	/*
296 	 * The max_buffer is used to snapshot the trace when a maximum
297 	 * latency is reached, or when the user initiates a snapshot.
298 	 * Some tracers will use this to store a maximum trace while
299 	 * it continues examining live traces.
300 	 *
301 	 * The buffers for the max_buffer are set up the same as the array_buffer
302 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
303 	 * with the buffer of the array_buffer and the buffers are reset for
304 	 * the array_buffer so the tracing can continue.
305 	 */
306 	struct array_buffer	max_buffer;
307 	bool			allocated_snapshot;
308 #endif
309 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
310 	|| defined(CONFIG_OSNOISE_TRACER)
311 	unsigned long		max_latency;
312 #ifdef CONFIG_FSNOTIFY
313 	struct dentry		*d_max_latency;
314 	struct work_struct	fsnotify_work;
315 	struct irq_work		fsnotify_irqwork;
316 #endif
317 #endif
318 	struct trace_pid_list	__rcu *filtered_pids;
319 	struct trace_pid_list	__rcu *filtered_no_pids;
320 	/*
321 	 * max_lock is used to protect the swapping of buffers
322 	 * when taking a max snapshot. The buffers themselves are
323 	 * protected by per_cpu spinlocks. But the action of the swap
324 	 * needs its own lock.
325 	 *
326 	 * This is defined as a arch_spinlock_t in order to help
327 	 * with performance when lockdep debugging is enabled.
328 	 *
329 	 * It is also used in other places outside the update_max_tr
330 	 * so it needs to be defined outside of the
331 	 * CONFIG_TRACER_MAX_TRACE.
332 	 */
333 	arch_spinlock_t		max_lock;
334 	int			buffer_disabled;
335 #ifdef CONFIG_FTRACE_SYSCALLS
336 	int			sys_refcount_enter;
337 	int			sys_refcount_exit;
338 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
339 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
340 #endif
341 	int			stop_count;
342 	int			clock_id;
343 	int			nr_topts;
344 	bool			clear_trace;
345 	int			buffer_percent;
346 	unsigned int		n_err_log_entries;
347 	struct tracer		*current_trace;
348 	unsigned int		trace_flags;
349 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
350 	unsigned int		flags;
351 	raw_spinlock_t		start_lock;
352 	struct list_head	err_log;
353 	struct dentry		*dir;
354 	struct dentry		*options;
355 	struct dentry		*percpu_dir;
356 	struct dentry		*event_dir;
357 	struct trace_options	*topts;
358 	struct list_head	systems;
359 	struct list_head	events;
360 	struct trace_event_file *trace_marker_file;
361 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
362 	int			ref;
363 	int			trace_ref;
364 #ifdef CONFIG_FUNCTION_TRACER
365 	struct ftrace_ops	*ops;
366 	struct trace_pid_list	__rcu *function_pids;
367 	struct trace_pid_list	__rcu *function_no_pids;
368 #ifdef CONFIG_DYNAMIC_FTRACE
369 	/* All of these are protected by the ftrace_lock */
370 	struct list_head	func_probes;
371 	struct list_head	mod_trace;
372 	struct list_head	mod_notrace;
373 #endif
374 	/* function tracing enabled */
375 	int			function_enabled;
376 #endif
377 	int			no_filter_buffering_ref;
378 	struct list_head	hist_vars;
379 #ifdef CONFIG_TRACER_SNAPSHOT
380 	struct cond_snapshot	*cond_snapshot;
381 #endif
382 	struct trace_func_repeats	__percpu *last_func_repeats;
383 };
384 
385 enum {
386 	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
387 };
388 
389 extern struct list_head ftrace_trace_arrays;
390 
391 extern struct mutex trace_types_lock;
392 
393 extern int trace_array_get(struct trace_array *tr);
394 extern int tracing_check_open_get_tr(struct trace_array *tr);
395 extern struct trace_array *trace_array_find(const char *instance);
396 extern struct trace_array *trace_array_find_get(const char *instance);
397 
398 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
399 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
400 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
401 
402 extern bool trace_clock_in_ns(struct trace_array *tr);
403 
404 /*
405  * The global tracer (top) should be the first trace array added,
406  * but we check the flag anyway.
407  */
408 static inline struct trace_array *top_trace_array(void)
409 {
410 	struct trace_array *tr;
411 
412 	if (list_empty(&ftrace_trace_arrays))
413 		return NULL;
414 
415 	tr = list_entry(ftrace_trace_arrays.prev,
416 			typeof(*tr), list);
417 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
418 	return tr;
419 }
420 
421 #define FTRACE_CMP_TYPE(var, type) \
422 	__builtin_types_compatible_p(typeof(var), type *)
423 
424 #undef IF_ASSIGN
425 #define IF_ASSIGN(var, entry, etype, id)			\
426 	if (FTRACE_CMP_TYPE(var, etype)) {			\
427 		var = (typeof(var))(entry);			\
428 		WARN_ON(id != 0 && (entry)->type != id);	\
429 		break;						\
430 	}
431 
432 /* Will cause compile errors if type is not found. */
433 extern void __ftrace_bad_type(void);
434 
435 /*
436  * The trace_assign_type is a verifier that the entry type is
437  * the same as the type being assigned. To add new types simply
438  * add a line with the following format:
439  *
440  * IF_ASSIGN(var, ent, type, id);
441  *
442  *  Where "type" is the trace type that includes the trace_entry
443  *  as the "ent" item. And "id" is the trace identifier that is
444  *  used in the trace_type enum.
445  *
446  *  If the type can have more than one id, then use zero.
447  */
448 #define trace_assign_type(var, ent)					\
449 	do {								\
450 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
451 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
452 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
453 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
454 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
455 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
456 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
457 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
458 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
459 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
460 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
461 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
462 			  TRACE_MMIO_RW);				\
463 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
464 			  TRACE_MMIO_MAP);				\
465 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
466 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
467 			  TRACE_GRAPH_ENT);		\
468 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
469 			  TRACE_GRAPH_RET);		\
470 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
471 			  TRACE_FUNC_REPEATS);				\
472 		__ftrace_bad_type();					\
473 	} while (0)
474 
475 /*
476  * An option specific to a tracer. This is a boolean value.
477  * The bit is the bit index that sets its value on the
478  * flags value in struct tracer_flags.
479  */
480 struct tracer_opt {
481 	const char	*name; /* Will appear on the trace_options file */
482 	u32		bit; /* Mask assigned in val field in tracer_flags */
483 };
484 
485 /*
486  * The set of specific options for a tracer. Your tracer
487  * have to set the initial value of the flags val.
488  */
489 struct tracer_flags {
490 	u32			val;
491 	struct tracer_opt	*opts;
492 	struct tracer		*trace;
493 };
494 
495 /* Makes more easy to define a tracer opt */
496 #define TRACER_OPT(s, b)	.name = #s, .bit = b
497 
498 
499 struct trace_option_dentry {
500 	struct tracer_opt		*opt;
501 	struct tracer_flags		*flags;
502 	struct trace_array		*tr;
503 	struct dentry			*entry;
504 };
505 
506 /**
507  * struct tracer - a specific tracer and its callbacks to interact with tracefs
508  * @name: the name chosen to select it on the available_tracers file
509  * @init: called when one switches to this tracer (echo name > current_tracer)
510  * @reset: called when one switches to another tracer
511  * @start: called when tracing is unpaused (echo 1 > tracing_on)
512  * @stop: called when tracing is paused (echo 0 > tracing_on)
513  * @update_thresh: called when tracing_thresh is updated
514  * @open: called when the trace file is opened
515  * @pipe_open: called when the trace_pipe file is opened
516  * @close: called when the trace file is released
517  * @pipe_close: called when the trace_pipe file is released
518  * @read: override the default read callback on trace_pipe
519  * @splice_read: override the default splice_read callback on trace_pipe
520  * @selftest: selftest to run on boot (see trace_selftest.c)
521  * @print_headers: override the first lines that describe your columns
522  * @print_line: callback that prints a trace
523  * @set_flag: signals one of your private flags changed (trace_options file)
524  * @flags: your private flags
525  */
526 struct tracer {
527 	const char		*name;
528 	int			(*init)(struct trace_array *tr);
529 	void			(*reset)(struct trace_array *tr);
530 	void			(*start)(struct trace_array *tr);
531 	void			(*stop)(struct trace_array *tr);
532 	int			(*update_thresh)(struct trace_array *tr);
533 	void			(*open)(struct trace_iterator *iter);
534 	void			(*pipe_open)(struct trace_iterator *iter);
535 	void			(*close)(struct trace_iterator *iter);
536 	void			(*pipe_close)(struct trace_iterator *iter);
537 	ssize_t			(*read)(struct trace_iterator *iter,
538 					struct file *filp, char __user *ubuf,
539 					size_t cnt, loff_t *ppos);
540 	ssize_t			(*splice_read)(struct trace_iterator *iter,
541 					       struct file *filp,
542 					       loff_t *ppos,
543 					       struct pipe_inode_info *pipe,
544 					       size_t len,
545 					       unsigned int flags);
546 #ifdef CONFIG_FTRACE_STARTUP_TEST
547 	int			(*selftest)(struct tracer *trace,
548 					    struct trace_array *tr);
549 #endif
550 	void			(*print_header)(struct seq_file *m);
551 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
552 	/* If you handled the flag setting, return 0 */
553 	int			(*set_flag)(struct trace_array *tr,
554 					    u32 old_flags, u32 bit, int set);
555 	/* Return 0 if OK with change, else return non-zero */
556 	int			(*flag_changed)(struct trace_array *tr,
557 						u32 mask, int set);
558 	struct tracer		*next;
559 	struct tracer_flags	*flags;
560 	int			enabled;
561 	bool			print_max;
562 	bool			allow_instances;
563 #ifdef CONFIG_TRACER_MAX_TRACE
564 	bool			use_max_tr;
565 #endif
566 	/* True if tracer cannot be enabled in kernel param */
567 	bool			noboot;
568 };
569 
570 static inline struct ring_buffer_iter *
571 trace_buffer_iter(struct trace_iterator *iter, int cpu)
572 {
573 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
574 }
575 
576 int tracer_init(struct tracer *t, struct trace_array *tr);
577 int tracing_is_enabled(void);
578 void tracing_reset_online_cpus(struct array_buffer *buf);
579 void tracing_reset_current(int cpu);
580 void tracing_reset_all_online_cpus(void);
581 int tracing_open_generic(struct inode *inode, struct file *filp);
582 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
583 bool tracing_is_disabled(void);
584 bool tracer_tracing_is_on(struct trace_array *tr);
585 void tracer_tracing_on(struct trace_array *tr);
586 void tracer_tracing_off(struct trace_array *tr);
587 struct dentry *trace_create_file(const char *name,
588 				 umode_t mode,
589 				 struct dentry *parent,
590 				 void *data,
591 				 const struct file_operations *fops);
592 
593 int tracing_init_dentry(void);
594 
595 struct ring_buffer_event;
596 
597 struct ring_buffer_event *
598 trace_buffer_lock_reserve(struct trace_buffer *buffer,
599 			  int type,
600 			  unsigned long len,
601 			  unsigned int trace_ctx);
602 
603 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
604 						struct trace_array_cpu *data);
605 
606 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
607 					  int *ent_cpu, u64 *ent_ts);
608 
609 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
610 					struct ring_buffer_event *event);
611 
612 bool trace_is_tracepoint_string(const char *str);
613 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
614 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
615 			 va_list ap);
616 
617 int trace_empty(struct trace_iterator *iter);
618 
619 void *trace_find_next_entry_inc(struct trace_iterator *iter);
620 
621 void trace_init_global_iter(struct trace_iterator *iter);
622 
623 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
624 
625 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
626 unsigned long trace_total_entries(struct trace_array *tr);
627 
628 void trace_function(struct trace_array *tr,
629 		    unsigned long ip,
630 		    unsigned long parent_ip,
631 		    unsigned int trace_ctx);
632 void trace_graph_function(struct trace_array *tr,
633 		    unsigned long ip,
634 		    unsigned long parent_ip,
635 		    unsigned int trace_ctx);
636 void trace_latency_header(struct seq_file *m);
637 void trace_default_header(struct seq_file *m);
638 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
639 
640 void trace_graph_return(struct ftrace_graph_ret *trace);
641 int trace_graph_entry(struct ftrace_graph_ent *trace);
642 void set_graph_array(struct trace_array *tr);
643 
644 void tracing_start_cmdline_record(void);
645 void tracing_stop_cmdline_record(void);
646 void tracing_start_tgid_record(void);
647 void tracing_stop_tgid_record(void);
648 
649 int register_tracer(struct tracer *type);
650 int is_tracing_stopped(void);
651 
652 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
653 
654 extern cpumask_var_t __read_mostly tracing_buffer_mask;
655 
656 #define for_each_tracing_cpu(cpu)	\
657 	for_each_cpu(cpu, tracing_buffer_mask)
658 
659 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
660 
661 extern unsigned long tracing_thresh;
662 
663 /* PID filtering */
664 
665 extern int pid_max;
666 
667 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
668 			     pid_t search_pid);
669 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
670 			    struct trace_pid_list *filtered_no_pids,
671 			    struct task_struct *task);
672 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
673 				  struct task_struct *self,
674 				  struct task_struct *task);
675 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
676 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
677 int trace_pid_show(struct seq_file *m, void *v);
678 void trace_free_pid_list(struct trace_pid_list *pid_list);
679 int trace_pid_write(struct trace_pid_list *filtered_pids,
680 		    struct trace_pid_list **new_pid_list,
681 		    const char __user *ubuf, size_t cnt);
682 
683 #ifdef CONFIG_TRACER_MAX_TRACE
684 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
685 		   void *cond_data);
686 void update_max_tr_single(struct trace_array *tr,
687 			  struct task_struct *tsk, int cpu);
688 #endif /* CONFIG_TRACER_MAX_TRACE */
689 
690 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
691 	|| defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY)
692 #define LATENCY_FS_NOTIFY
693 #endif
694 
695 #ifdef LATENCY_FS_NOTIFY
696 void latency_fsnotify(struct trace_array *tr);
697 #else
698 static inline void latency_fsnotify(struct trace_array *tr) { }
699 #endif
700 
701 #ifdef CONFIG_STACKTRACE
702 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
703 #else
704 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
705 				 int skip)
706 {
707 }
708 #endif /* CONFIG_STACKTRACE */
709 
710 void trace_last_func_repeats(struct trace_array *tr,
711 			     struct trace_func_repeats *last_info,
712 			     unsigned int trace_ctx);
713 
714 extern u64 ftrace_now(int cpu);
715 
716 extern void trace_find_cmdline(int pid, char comm[]);
717 extern int trace_find_tgid(int pid);
718 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
719 
720 #ifdef CONFIG_DYNAMIC_FTRACE
721 extern unsigned long ftrace_update_tot_cnt;
722 extern unsigned long ftrace_number_of_pages;
723 extern unsigned long ftrace_number_of_groups;
724 void ftrace_init_trace_array(struct trace_array *tr);
725 #else
726 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
727 #endif
728 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
729 extern int DYN_FTRACE_TEST_NAME(void);
730 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
731 extern int DYN_FTRACE_TEST_NAME2(void);
732 
733 extern bool ring_buffer_expanded;
734 extern bool tracing_selftest_disabled;
735 
736 #ifdef CONFIG_FTRACE_STARTUP_TEST
737 extern void __init disable_tracing_selftest(const char *reason);
738 
739 extern int trace_selftest_startup_function(struct tracer *trace,
740 					   struct trace_array *tr);
741 extern int trace_selftest_startup_function_graph(struct tracer *trace,
742 						 struct trace_array *tr);
743 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
744 					  struct trace_array *tr);
745 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
746 					     struct trace_array *tr);
747 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
748 						 struct trace_array *tr);
749 extern int trace_selftest_startup_wakeup(struct tracer *trace,
750 					 struct trace_array *tr);
751 extern int trace_selftest_startup_nop(struct tracer *trace,
752 					 struct trace_array *tr);
753 extern int trace_selftest_startup_branch(struct tracer *trace,
754 					 struct trace_array *tr);
755 /*
756  * Tracer data references selftest functions that only occur
757  * on boot up. These can be __init functions. Thus, when selftests
758  * are enabled, then the tracers need to reference __init functions.
759  */
760 #define __tracer_data		__refdata
761 #else
762 static inline void __init disable_tracing_selftest(const char *reason)
763 {
764 }
765 /* Tracers are seldom changed. Optimize when selftests are disabled. */
766 #define __tracer_data		__read_mostly
767 #endif /* CONFIG_FTRACE_STARTUP_TEST */
768 
769 extern void *head_page(struct trace_array_cpu *data);
770 extern unsigned long long ns2usecs(u64 nsec);
771 extern int
772 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
773 extern int
774 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
775 extern int
776 trace_array_vprintk(struct trace_array *tr,
777 		    unsigned long ip, const char *fmt, va_list args);
778 int trace_array_printk_buf(struct trace_buffer *buffer,
779 			   unsigned long ip, const char *fmt, ...);
780 void trace_printk_seq(struct trace_seq *s);
781 enum print_line_t print_trace_line(struct trace_iterator *iter);
782 
783 extern char trace_find_mark(unsigned long long duration);
784 
785 struct ftrace_hash;
786 
787 struct ftrace_mod_load {
788 	struct list_head	list;
789 	char			*func;
790 	char			*module;
791 	int			 enable;
792 };
793 
794 enum {
795 	FTRACE_HASH_FL_MOD	= (1 << 0),
796 };
797 
798 struct ftrace_hash {
799 	unsigned long		size_bits;
800 	struct hlist_head	*buckets;
801 	unsigned long		count;
802 	unsigned long		flags;
803 	struct rcu_head		rcu;
804 };
805 
806 struct ftrace_func_entry *
807 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
808 
809 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
810 {
811 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
812 }
813 
814 /* Standard output formatting function used for function return traces */
815 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
816 
817 /* Flag options */
818 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
819 #define TRACE_GRAPH_PRINT_CPU           0x2
820 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
821 #define TRACE_GRAPH_PRINT_PROC          0x8
822 #define TRACE_GRAPH_PRINT_DURATION      0x10
823 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
824 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
825 #define TRACE_GRAPH_PRINT_IRQS          0x80
826 #define TRACE_GRAPH_PRINT_TAIL          0x100
827 #define TRACE_GRAPH_SLEEP_TIME          0x200
828 #define TRACE_GRAPH_GRAPH_TIME          0x400
829 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
830 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
831 
832 extern void ftrace_graph_sleep_time_control(bool enable);
833 
834 #ifdef CONFIG_FUNCTION_PROFILER
835 extern void ftrace_graph_graph_time_control(bool enable);
836 #else
837 static inline void ftrace_graph_graph_time_control(bool enable) { }
838 #endif
839 
840 extern enum print_line_t
841 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
842 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
843 extern void
844 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
845 extern void graph_trace_open(struct trace_iterator *iter);
846 extern void graph_trace_close(struct trace_iterator *iter);
847 extern int __trace_graph_entry(struct trace_array *tr,
848 			       struct ftrace_graph_ent *trace,
849 			       unsigned int trace_ctx);
850 extern void __trace_graph_return(struct trace_array *tr,
851 				 struct ftrace_graph_ret *trace,
852 				 unsigned int trace_ctx);
853 
854 #ifdef CONFIG_DYNAMIC_FTRACE
855 extern struct ftrace_hash __rcu *ftrace_graph_hash;
856 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
857 
858 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
859 {
860 	unsigned long addr = trace->func;
861 	int ret = 0;
862 	struct ftrace_hash *hash;
863 
864 	preempt_disable_notrace();
865 
866 	/*
867 	 * Have to open code "rcu_dereference_sched()" because the
868 	 * function graph tracer can be called when RCU is not
869 	 * "watching".
870 	 * Protected with schedule_on_each_cpu(ftrace_sync)
871 	 */
872 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
873 
874 	if (ftrace_hash_empty(hash)) {
875 		ret = 1;
876 		goto out;
877 	}
878 
879 	if (ftrace_lookup_ip(hash, addr)) {
880 
881 		/*
882 		 * This needs to be cleared on the return functions
883 		 * when the depth is zero.
884 		 */
885 		trace_recursion_set(TRACE_GRAPH_BIT);
886 		trace_recursion_set_depth(trace->depth);
887 
888 		/*
889 		 * If no irqs are to be traced, but a set_graph_function
890 		 * is set, and called by an interrupt handler, we still
891 		 * want to trace it.
892 		 */
893 		if (in_hardirq())
894 			trace_recursion_set(TRACE_IRQ_BIT);
895 		else
896 			trace_recursion_clear(TRACE_IRQ_BIT);
897 		ret = 1;
898 	}
899 
900 out:
901 	preempt_enable_notrace();
902 	return ret;
903 }
904 
905 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
906 {
907 	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
908 	    trace->depth == trace_recursion_depth())
909 		trace_recursion_clear(TRACE_GRAPH_BIT);
910 }
911 
912 static inline int ftrace_graph_notrace_addr(unsigned long addr)
913 {
914 	int ret = 0;
915 	struct ftrace_hash *notrace_hash;
916 
917 	preempt_disable_notrace();
918 
919 	/*
920 	 * Have to open code "rcu_dereference_sched()" because the
921 	 * function graph tracer can be called when RCU is not
922 	 * "watching".
923 	 * Protected with schedule_on_each_cpu(ftrace_sync)
924 	 */
925 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
926 						 !preemptible());
927 
928 	if (ftrace_lookup_ip(notrace_hash, addr))
929 		ret = 1;
930 
931 	preempt_enable_notrace();
932 	return ret;
933 }
934 #else
935 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
936 {
937 	return 1;
938 }
939 
940 static inline int ftrace_graph_notrace_addr(unsigned long addr)
941 {
942 	return 0;
943 }
944 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
945 { }
946 #endif /* CONFIG_DYNAMIC_FTRACE */
947 
948 extern unsigned int fgraph_max_depth;
949 
950 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
951 {
952 	/* trace it when it is-nested-in or is a function enabled. */
953 	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
954 		 ftrace_graph_addr(trace)) ||
955 		(trace->depth < 0) ||
956 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
957 }
958 
959 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
960 static inline enum print_line_t
961 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
962 {
963 	return TRACE_TYPE_UNHANDLED;
964 }
965 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
966 
967 extern struct list_head ftrace_pids;
968 
969 #ifdef CONFIG_FUNCTION_TRACER
970 
971 #define FTRACE_PID_IGNORE	-1
972 #define FTRACE_PID_TRACE	-2
973 
974 struct ftrace_func_command {
975 	struct list_head	list;
976 	char			*name;
977 	int			(*func)(struct trace_array *tr,
978 					struct ftrace_hash *hash,
979 					char *func, char *cmd,
980 					char *params, int enable);
981 };
982 extern bool ftrace_filter_param __initdata;
983 static inline int ftrace_trace_task(struct trace_array *tr)
984 {
985 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
986 		FTRACE_PID_IGNORE;
987 }
988 extern int ftrace_is_dead(void);
989 int ftrace_create_function_files(struct trace_array *tr,
990 				 struct dentry *parent);
991 void ftrace_destroy_function_files(struct trace_array *tr);
992 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
993 void ftrace_free_ftrace_ops(struct trace_array *tr);
994 void ftrace_init_global_array_ops(struct trace_array *tr);
995 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
996 void ftrace_reset_array_ops(struct trace_array *tr);
997 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
998 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
999 				  struct dentry *d_tracer);
1000 void ftrace_clear_pids(struct trace_array *tr);
1001 int init_function_trace(void);
1002 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1003 #else
1004 static inline int ftrace_trace_task(struct trace_array *tr)
1005 {
1006 	return 1;
1007 }
1008 static inline int ftrace_is_dead(void) { return 0; }
1009 static inline int
1010 ftrace_create_function_files(struct trace_array *tr,
1011 			     struct dentry *parent)
1012 {
1013 	return 0;
1014 }
1015 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1016 {
1017 	return 0;
1018 }
1019 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1020 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1021 static inline __init void
1022 ftrace_init_global_array_ops(struct trace_array *tr) { }
1023 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1024 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1025 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1026 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1027 static inline int init_function_trace(void) { return 0; }
1028 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1029 /* ftace_func_t type is not defined, use macro instead of static inline */
1030 #define ftrace_init_array_ops(tr, func) do { } while (0)
1031 #endif /* CONFIG_FUNCTION_TRACER */
1032 
1033 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1034 
1035 struct ftrace_probe_ops {
1036 	void			(*func)(unsigned long ip,
1037 					unsigned long parent_ip,
1038 					struct trace_array *tr,
1039 					struct ftrace_probe_ops *ops,
1040 					void *data);
1041 	int			(*init)(struct ftrace_probe_ops *ops,
1042 					struct trace_array *tr,
1043 					unsigned long ip, void *init_data,
1044 					void **data);
1045 	void			(*free)(struct ftrace_probe_ops *ops,
1046 					struct trace_array *tr,
1047 					unsigned long ip, void *data);
1048 	int			(*print)(struct seq_file *m,
1049 					 unsigned long ip,
1050 					 struct ftrace_probe_ops *ops,
1051 					 void *data);
1052 };
1053 
1054 struct ftrace_func_mapper;
1055 typedef int (*ftrace_mapper_func)(void *data);
1056 
1057 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1058 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1059 					   unsigned long ip);
1060 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1061 			       unsigned long ip, void *data);
1062 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1063 				   unsigned long ip);
1064 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1065 			     ftrace_mapper_func free_func);
1066 
1067 extern int
1068 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1069 			       struct ftrace_probe_ops *ops, void *data);
1070 extern int
1071 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1072 				      struct ftrace_probe_ops *ops);
1073 extern void clear_ftrace_function_probes(struct trace_array *tr);
1074 
1075 int register_ftrace_command(struct ftrace_func_command *cmd);
1076 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1077 
1078 void ftrace_create_filter_files(struct ftrace_ops *ops,
1079 				struct dentry *parent);
1080 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1081 
1082 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1083 			     int len, int reset);
1084 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1085 			      int len, int reset);
1086 #else
1087 struct ftrace_func_command;
1088 
1089 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1090 {
1091 	return -EINVAL;
1092 }
1093 static inline __init int unregister_ftrace_command(char *cmd_name)
1094 {
1095 	return -EINVAL;
1096 }
1097 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1098 {
1099 }
1100 
1101 /*
1102  * The ops parameter passed in is usually undefined.
1103  * This must be a macro.
1104  */
1105 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1106 #define ftrace_destroy_filter_files(ops) do { } while (0)
1107 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1108 
1109 bool ftrace_event_is_function(struct trace_event_call *call);
1110 
1111 /*
1112  * struct trace_parser - servers for reading the user input separated by spaces
1113  * @cont: set if the input is not complete - no final space char was found
1114  * @buffer: holds the parsed user input
1115  * @idx: user input length
1116  * @size: buffer size
1117  */
1118 struct trace_parser {
1119 	bool		cont;
1120 	char		*buffer;
1121 	unsigned	idx;
1122 	unsigned	size;
1123 };
1124 
1125 static inline bool trace_parser_loaded(struct trace_parser *parser)
1126 {
1127 	return (parser->idx != 0);
1128 }
1129 
1130 static inline bool trace_parser_cont(struct trace_parser *parser)
1131 {
1132 	return parser->cont;
1133 }
1134 
1135 static inline void trace_parser_clear(struct trace_parser *parser)
1136 {
1137 	parser->cont = false;
1138 	parser->idx = 0;
1139 }
1140 
1141 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1142 extern void trace_parser_put(struct trace_parser *parser);
1143 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1144 	size_t cnt, loff_t *ppos);
1145 
1146 /*
1147  * Only create function graph options if function graph is configured.
1148  */
1149 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1150 # define FGRAPH_FLAGS						\
1151 		C(DISPLAY_GRAPH,	"display-graph"),
1152 #else
1153 # define FGRAPH_FLAGS
1154 #endif
1155 
1156 #ifdef CONFIG_BRANCH_TRACER
1157 # define BRANCH_FLAGS					\
1158 		C(BRANCH,		"branch"),
1159 #else
1160 # define BRANCH_FLAGS
1161 #endif
1162 
1163 #ifdef CONFIG_FUNCTION_TRACER
1164 # define FUNCTION_FLAGS						\
1165 		C(FUNCTION,		"function-trace"),	\
1166 		C(FUNC_FORK,		"function-fork"),
1167 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1168 #else
1169 # define FUNCTION_FLAGS
1170 # define FUNCTION_DEFAULT_FLAGS		0UL
1171 # define TRACE_ITER_FUNC_FORK		0UL
1172 #endif
1173 
1174 #ifdef CONFIG_STACKTRACE
1175 # define STACK_FLAGS				\
1176 		C(STACKTRACE,		"stacktrace"),
1177 #else
1178 # define STACK_FLAGS
1179 #endif
1180 
1181 /*
1182  * trace_iterator_flags is an enumeration that defines bit
1183  * positions into trace_flags that controls the output.
1184  *
1185  * NOTE: These bits must match the trace_options array in
1186  *       trace.c (this macro guarantees it).
1187  */
1188 #define TRACE_FLAGS						\
1189 		C(PRINT_PARENT,		"print-parent"),	\
1190 		C(SYM_OFFSET,		"sym-offset"),		\
1191 		C(SYM_ADDR,		"sym-addr"),		\
1192 		C(VERBOSE,		"verbose"),		\
1193 		C(RAW,			"raw"),			\
1194 		C(HEX,			"hex"),			\
1195 		C(BIN,			"bin"),			\
1196 		C(BLOCK,		"block"),		\
1197 		C(PRINTK,		"trace_printk"),	\
1198 		C(ANNOTATE,		"annotate"),		\
1199 		C(USERSTACKTRACE,	"userstacktrace"),	\
1200 		C(SYM_USEROBJ,		"sym-userobj"),		\
1201 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1202 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1203 		C(LATENCY_FMT,		"latency-format"),	\
1204 		C(RECORD_CMD,		"record-cmd"),		\
1205 		C(RECORD_TGID,		"record-tgid"),		\
1206 		C(OVERWRITE,		"overwrite"),		\
1207 		C(STOP_ON_FREE,		"disable_on_free"),	\
1208 		C(IRQ_INFO,		"irq-info"),		\
1209 		C(MARKERS,		"markers"),		\
1210 		C(EVENT_FORK,		"event-fork"),		\
1211 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1212 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1213 		FUNCTION_FLAGS					\
1214 		FGRAPH_FLAGS					\
1215 		STACK_FLAGS					\
1216 		BRANCH_FLAGS
1217 
1218 /*
1219  * By defining C, we can make TRACE_FLAGS a list of bit names
1220  * that will define the bits for the flag masks.
1221  */
1222 #undef C
1223 #define C(a, b) TRACE_ITER_##a##_BIT
1224 
1225 enum trace_iterator_bits {
1226 	TRACE_FLAGS
1227 	/* Make sure we don't go more than we have bits for */
1228 	TRACE_ITER_LAST_BIT
1229 };
1230 
1231 /*
1232  * By redefining C, we can make TRACE_FLAGS a list of masks that
1233  * use the bits as defined above.
1234  */
1235 #undef C
1236 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1237 
1238 enum trace_iterator_flags { TRACE_FLAGS };
1239 
1240 /*
1241  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1242  * control the output of kernel symbols.
1243  */
1244 #define TRACE_ITER_SYM_MASK \
1245 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1246 
1247 extern struct tracer nop_trace;
1248 
1249 #ifdef CONFIG_BRANCH_TRACER
1250 extern int enable_branch_tracing(struct trace_array *tr);
1251 extern void disable_branch_tracing(void);
1252 static inline int trace_branch_enable(struct trace_array *tr)
1253 {
1254 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1255 		return enable_branch_tracing(tr);
1256 	return 0;
1257 }
1258 static inline void trace_branch_disable(void)
1259 {
1260 	/* due to races, always disable */
1261 	disable_branch_tracing();
1262 }
1263 #else
1264 static inline int trace_branch_enable(struct trace_array *tr)
1265 {
1266 	return 0;
1267 }
1268 static inline void trace_branch_disable(void)
1269 {
1270 }
1271 #endif /* CONFIG_BRANCH_TRACER */
1272 
1273 /* set ring buffers to default size if not already done so */
1274 int tracing_update_buffers(void);
1275 
1276 struct ftrace_event_field {
1277 	struct list_head	link;
1278 	const char		*name;
1279 	const char		*type;
1280 	int			filter_type;
1281 	int			offset;
1282 	int			size;
1283 	int			is_signed;
1284 };
1285 
1286 struct prog_entry;
1287 
1288 struct event_filter {
1289 	struct prog_entry __rcu	*prog;
1290 	char			*filter_string;
1291 };
1292 
1293 struct event_subsystem {
1294 	struct list_head	list;
1295 	const char		*name;
1296 	struct event_filter	*filter;
1297 	int			ref_count;
1298 };
1299 
1300 struct trace_subsystem_dir {
1301 	struct list_head		list;
1302 	struct event_subsystem		*subsystem;
1303 	struct trace_array		*tr;
1304 	struct dentry			*entry;
1305 	int				ref_count;
1306 	int				nr_events;
1307 };
1308 
1309 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1310 				     struct trace_buffer *buffer,
1311 				     struct ring_buffer_event *event);
1312 
1313 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1314 				     struct trace_buffer *buffer,
1315 				     struct ring_buffer_event *event,
1316 				     unsigned int trcace_ctx,
1317 				     struct pt_regs *regs);
1318 
1319 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1320 					      struct trace_buffer *buffer,
1321 					      struct ring_buffer_event *event,
1322 					      unsigned int trace_ctx)
1323 {
1324 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1325 }
1326 
1327 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1328 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1329 void trace_buffered_event_disable(void);
1330 void trace_buffered_event_enable(void);
1331 
1332 static inline void
1333 __trace_event_discard_commit(struct trace_buffer *buffer,
1334 			     struct ring_buffer_event *event)
1335 {
1336 	if (this_cpu_read(trace_buffered_event) == event) {
1337 		/* Simply release the temp buffer */
1338 		this_cpu_dec(trace_buffered_event_cnt);
1339 		return;
1340 	}
1341 	ring_buffer_discard_commit(buffer, event);
1342 }
1343 
1344 /*
1345  * Helper function for event_trigger_unlock_commit{_regs}().
1346  * If there are event triggers attached to this event that requires
1347  * filtering against its fields, then they will be called as the
1348  * entry already holds the field information of the current event.
1349  *
1350  * It also checks if the event should be discarded or not.
1351  * It is to be discarded if the event is soft disabled and the
1352  * event was only recorded to process triggers, or if the event
1353  * filter is active and this event did not match the filters.
1354  *
1355  * Returns true if the event is discarded, false otherwise.
1356  */
1357 static inline bool
1358 __event_trigger_test_discard(struct trace_event_file *file,
1359 			     struct trace_buffer *buffer,
1360 			     struct ring_buffer_event *event,
1361 			     void *entry,
1362 			     enum event_trigger_type *tt)
1363 {
1364 	unsigned long eflags = file->flags;
1365 
1366 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1367 		*tt = event_triggers_call(file, buffer, entry, event);
1368 
1369 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1370 				    EVENT_FILE_FL_FILTERED |
1371 				    EVENT_FILE_FL_PID_FILTER))))
1372 		return false;
1373 
1374 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1375 		goto discard;
1376 
1377 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1378 	    !filter_match_preds(file->filter, entry))
1379 		goto discard;
1380 
1381 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1382 	    trace_event_ignore_this_pid(file))
1383 		goto discard;
1384 
1385 	return false;
1386  discard:
1387 	__trace_event_discard_commit(buffer, event);
1388 	return true;
1389 }
1390 
1391 /**
1392  * event_trigger_unlock_commit - handle triggers and finish event commit
1393  * @file: The file pointer associated with the event
1394  * @buffer: The ring buffer that the event is being written to
1395  * @event: The event meta data in the ring buffer
1396  * @entry: The event itself
1397  * @trace_ctx: The tracing context flags.
1398  *
1399  * This is a helper function to handle triggers that require data
1400  * from the event itself. It also tests the event against filters and
1401  * if the event is soft disabled and should be discarded.
1402  */
1403 static inline void
1404 event_trigger_unlock_commit(struct trace_event_file *file,
1405 			    struct trace_buffer *buffer,
1406 			    struct ring_buffer_event *event,
1407 			    void *entry, unsigned int trace_ctx)
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(file->tr, buffer, event, trace_ctx);
1413 
1414 	if (tt)
1415 		event_triggers_post_call(file, tt);
1416 }
1417 
1418 #define FILTER_PRED_INVALID	((unsigned short)-1)
1419 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1420 #define FILTER_PRED_FOLD	(1 << 15)
1421 
1422 /*
1423  * The max preds is the size of unsigned short with
1424  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1425  * and FOLD flags. The other is reserved.
1426  *
1427  * 2^14 preds is way more than enough.
1428  */
1429 #define MAX_FILTER_PRED		16384
1430 
1431 struct filter_pred;
1432 struct regex;
1433 
1434 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1435 
1436 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1437 
1438 enum regex_type {
1439 	MATCH_FULL = 0,
1440 	MATCH_FRONT_ONLY,
1441 	MATCH_MIDDLE_ONLY,
1442 	MATCH_END_ONLY,
1443 	MATCH_GLOB,
1444 	MATCH_INDEX,
1445 };
1446 
1447 struct regex {
1448 	char			pattern[MAX_FILTER_STR_VAL];
1449 	int			len;
1450 	int			field_len;
1451 	regex_match_func	match;
1452 };
1453 
1454 struct filter_pred {
1455 	filter_pred_fn_t 	fn;
1456 	u64 			val;
1457 	struct regex		regex;
1458 	unsigned short		*ops;
1459 	struct ftrace_event_field *field;
1460 	int 			offset;
1461 	int			not;
1462 	int 			op;
1463 };
1464 
1465 static inline bool is_string_field(struct ftrace_event_field *field)
1466 {
1467 	return field->filter_type == FILTER_DYN_STRING ||
1468 	       field->filter_type == FILTER_STATIC_STRING ||
1469 	       field->filter_type == FILTER_PTR_STRING ||
1470 	       field->filter_type == FILTER_COMM;
1471 }
1472 
1473 static inline bool is_function_field(struct ftrace_event_field *field)
1474 {
1475 	return field->filter_type == FILTER_TRACE_FN;
1476 }
1477 
1478 extern enum regex_type
1479 filter_parse_regex(char *buff, int len, char **search, int *not);
1480 extern void print_event_filter(struct trace_event_file *file,
1481 			       struct trace_seq *s);
1482 extern int apply_event_filter(struct trace_event_file *file,
1483 			      char *filter_string);
1484 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1485 					char *filter_string);
1486 extern void print_subsystem_event_filter(struct event_subsystem *system,
1487 					 struct trace_seq *s);
1488 extern int filter_assign_type(const char *type);
1489 extern int create_event_filter(struct trace_array *tr,
1490 			       struct trace_event_call *call,
1491 			       char *filter_str, bool set_str,
1492 			       struct event_filter **filterp);
1493 extern void free_event_filter(struct event_filter *filter);
1494 
1495 struct ftrace_event_field *
1496 trace_find_event_field(struct trace_event_call *call, char *name);
1497 
1498 extern void trace_event_enable_cmd_record(bool enable);
1499 extern void trace_event_enable_tgid_record(bool enable);
1500 
1501 extern int event_trace_init(void);
1502 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1503 extern int event_trace_del_tracer(struct trace_array *tr);
1504 extern void __trace_early_add_events(struct trace_array *tr);
1505 
1506 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1507 						  const char *system,
1508 						  const char *event);
1509 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1510 						const char *system,
1511 						const char *event);
1512 
1513 static inline void *event_file_data(struct file *filp)
1514 {
1515 	return READ_ONCE(file_inode(filp)->i_private);
1516 }
1517 
1518 extern struct mutex event_mutex;
1519 extern struct list_head ftrace_events;
1520 
1521 extern const struct file_operations event_trigger_fops;
1522 extern const struct file_operations event_hist_fops;
1523 extern const struct file_operations event_hist_debug_fops;
1524 extern const struct file_operations event_inject_fops;
1525 
1526 #ifdef CONFIG_HIST_TRIGGERS
1527 extern int register_trigger_hist_cmd(void);
1528 extern int register_trigger_hist_enable_disable_cmds(void);
1529 #else
1530 static inline int register_trigger_hist_cmd(void) { return 0; }
1531 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1532 #endif
1533 
1534 extern int register_trigger_cmds(void);
1535 extern void clear_event_triggers(struct trace_array *tr);
1536 
1537 enum {
1538 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1539 };
1540 
1541 struct event_trigger_data {
1542 	unsigned long			count;
1543 	int				ref;
1544 	int				flags;
1545 	struct event_trigger_ops	*ops;
1546 	struct event_command		*cmd_ops;
1547 	struct event_filter __rcu	*filter;
1548 	char				*filter_str;
1549 	void				*private_data;
1550 	bool				paused;
1551 	bool				paused_tmp;
1552 	struct list_head		list;
1553 	char				*name;
1554 	struct list_head		named_list;
1555 	struct event_trigger_data	*named_data;
1556 };
1557 
1558 /* Avoid typos */
1559 #define ENABLE_EVENT_STR	"enable_event"
1560 #define DISABLE_EVENT_STR	"disable_event"
1561 #define ENABLE_HIST_STR		"enable_hist"
1562 #define DISABLE_HIST_STR	"disable_hist"
1563 
1564 struct enable_trigger_data {
1565 	struct trace_event_file		*file;
1566 	bool				enable;
1567 	bool				hist;
1568 };
1569 
1570 extern int event_enable_trigger_print(struct seq_file *m,
1571 				      struct event_trigger_ops *ops,
1572 				      struct event_trigger_data *data);
1573 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1574 				      struct event_trigger_data *data);
1575 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1576 				     struct trace_event_file *file,
1577 				     char *glob, char *cmd, char *param);
1578 extern int event_enable_register_trigger(char *glob,
1579 					 struct event_trigger_ops *ops,
1580 					 struct event_trigger_data *data,
1581 					 struct trace_event_file *file);
1582 extern void event_enable_unregister_trigger(char *glob,
1583 					    struct event_trigger_ops *ops,
1584 					    struct event_trigger_data *test,
1585 					    struct trace_event_file *file);
1586 extern void trigger_data_free(struct event_trigger_data *data);
1587 extern int event_trigger_init(struct event_trigger_ops *ops,
1588 			      struct event_trigger_data *data);
1589 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1590 					      int trigger_enable);
1591 extern void update_cond_flag(struct trace_event_file *file);
1592 extern int set_trigger_filter(char *filter_str,
1593 			      struct event_trigger_data *trigger_data,
1594 			      struct trace_event_file *file);
1595 extern struct event_trigger_data *find_named_trigger(const char *name);
1596 extern bool is_named_trigger(struct event_trigger_data *test);
1597 extern int save_named_trigger(const char *name,
1598 			      struct event_trigger_data *data);
1599 extern void del_named_trigger(struct event_trigger_data *data);
1600 extern void pause_named_trigger(struct event_trigger_data *data);
1601 extern void unpause_named_trigger(struct event_trigger_data *data);
1602 extern void set_named_trigger_data(struct event_trigger_data *data,
1603 				   struct event_trigger_data *named_data);
1604 extern struct event_trigger_data *
1605 get_named_trigger_data(struct event_trigger_data *data);
1606 extern int register_event_command(struct event_command *cmd);
1607 extern int unregister_event_command(struct event_command *cmd);
1608 extern int register_trigger_hist_enable_disable_cmds(void);
1609 
1610 /**
1611  * struct event_trigger_ops - callbacks for trace event triggers
1612  *
1613  * The methods in this structure provide per-event trigger hooks for
1614  * various trigger operations.
1615  *
1616  * All the methods below, except for @init() and @free(), must be
1617  * implemented.
1618  *
1619  * @func: The trigger 'probe' function called when the triggering
1620  *	event occurs.  The data passed into this callback is the data
1621  *	that was supplied to the event_command @reg() function that
1622  *	registered the trigger (see struct event_command) along with
1623  *	the trace record, rec.
1624  *
1625  * @init: An optional initialization function called for the trigger
1626  *	when the trigger is registered (via the event_command reg()
1627  *	function).  This can be used to perform per-trigger
1628  *	initialization such as incrementing a per-trigger reference
1629  *	count, for instance.  This is usually implemented by the
1630  *	generic utility function @event_trigger_init() (see
1631  *	trace_event_triggers.c).
1632  *
1633  * @free: An optional de-initialization function called for the
1634  *	trigger when the trigger is unregistered (via the
1635  *	event_command @reg() function).  This can be used to perform
1636  *	per-trigger de-initialization such as decrementing a
1637  *	per-trigger reference count and freeing corresponding trigger
1638  *	data, for instance.  This is usually implemented by the
1639  *	generic utility function @event_trigger_free() (see
1640  *	trace_event_triggers.c).
1641  *
1642  * @print: The callback function invoked to have the trigger print
1643  *	itself.  This is usually implemented by a wrapper function
1644  *	that calls the generic utility function @event_trigger_print()
1645  *	(see trace_event_triggers.c).
1646  */
1647 struct event_trigger_ops {
1648 	void			(*func)(struct event_trigger_data *data,
1649 					struct trace_buffer *buffer, void *rec,
1650 					struct ring_buffer_event *rbe);
1651 	int			(*init)(struct event_trigger_ops *ops,
1652 					struct event_trigger_data *data);
1653 	void			(*free)(struct event_trigger_ops *ops,
1654 					struct event_trigger_data *data);
1655 	int			(*print)(struct seq_file *m,
1656 					 struct event_trigger_ops *ops,
1657 					 struct event_trigger_data *data);
1658 };
1659 
1660 /**
1661  * struct event_command - callbacks and data members for event commands
1662  *
1663  * Event commands are invoked by users by writing the command name
1664  * into the 'trigger' file associated with a trace event.  The
1665  * parameters associated with a specific invocation of an event
1666  * command are used to create an event trigger instance, which is
1667  * added to the list of trigger instances associated with that trace
1668  * event.  When the event is hit, the set of triggers associated with
1669  * that event is invoked.
1670  *
1671  * The data members in this structure provide per-event command data
1672  * for various event commands.
1673  *
1674  * All the data members below, except for @post_trigger, must be set
1675  * for each event command.
1676  *
1677  * @name: The unique name that identifies the event command.  This is
1678  *	the name used when setting triggers via trigger files.
1679  *
1680  * @trigger_type: A unique id that identifies the event command
1681  *	'type'.  This value has two purposes, the first to ensure that
1682  *	only one trigger of the same type can be set at a given time
1683  *	for a particular event e.g. it doesn't make sense to have both
1684  *	a traceon and traceoff trigger attached to a single event at
1685  *	the same time, so traceon and traceoff have the same type
1686  *	though they have different names.  The @trigger_type value is
1687  *	also used as a bit value for deferring the actual trigger
1688  *	action until after the current event is finished.  Some
1689  *	commands need to do this if they themselves log to the trace
1690  *	buffer (see the @post_trigger() member below).  @trigger_type
1691  *	values are defined by adding new values to the trigger_type
1692  *	enum in include/linux/trace_events.h.
1693  *
1694  * @flags: See the enum event_command_flags below.
1695  *
1696  * All the methods below, except for @set_filter() and @unreg_all(),
1697  * must be implemented.
1698  *
1699  * @func: The callback function responsible for parsing and
1700  *	registering the trigger written to the 'trigger' file by the
1701  *	user.  It allocates the trigger instance and registers it with
1702  *	the appropriate trace event.  It makes use of the other
1703  *	event_command callback functions to orchestrate this, and is
1704  *	usually implemented by the generic utility function
1705  *	@event_trigger_callback() (see trace_event_triggers.c).
1706  *
1707  * @reg: Adds the trigger to the list of triggers associated with the
1708  *	event, and enables the event trigger itself, after
1709  *	initializing it (via the event_trigger_ops @init() function).
1710  *	This is also where commands can use the @trigger_type value to
1711  *	make the decision as to whether or not multiple instances of
1712  *	the trigger should be allowed.  This is usually implemented by
1713  *	the generic utility function @register_trigger() (see
1714  *	trace_event_triggers.c).
1715  *
1716  * @unreg: Removes the trigger from the list of triggers associated
1717  *	with the event, and disables the event trigger itself, after
1718  *	initializing it (via the event_trigger_ops @free() function).
1719  *	This is usually implemented by the generic utility function
1720  *	@unregister_trigger() (see trace_event_triggers.c).
1721  *
1722  * @unreg_all: An optional function called to remove all the triggers
1723  *	from the list of triggers associated with the event.  Called
1724  *	when a trigger file is opened in truncate mode.
1725  *
1726  * @set_filter: An optional function called to parse and set a filter
1727  *	for the trigger.  If no @set_filter() method is set for the
1728  *	event command, filters set by the user for the command will be
1729  *	ignored.  This is usually implemented by the generic utility
1730  *	function @set_trigger_filter() (see trace_event_triggers.c).
1731  *
1732  * @get_trigger_ops: The callback function invoked to retrieve the
1733  *	event_trigger_ops implementation associated with the command.
1734  */
1735 struct event_command {
1736 	struct list_head	list;
1737 	char			*name;
1738 	enum event_trigger_type	trigger_type;
1739 	int			flags;
1740 	int			(*func)(struct event_command *cmd_ops,
1741 					struct trace_event_file *file,
1742 					char *glob, char *cmd, char *params);
1743 	int			(*reg)(char *glob,
1744 				       struct event_trigger_ops *ops,
1745 				       struct event_trigger_data *data,
1746 				       struct trace_event_file *file);
1747 	void			(*unreg)(char *glob,
1748 					 struct event_trigger_ops *ops,
1749 					 struct event_trigger_data *data,
1750 					 struct trace_event_file *file);
1751 	void			(*unreg_all)(struct trace_event_file *file);
1752 	int			(*set_filter)(char *filter_str,
1753 					      struct event_trigger_data *data,
1754 					      struct trace_event_file *file);
1755 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1756 };
1757 
1758 /**
1759  * enum event_command_flags - flags for struct event_command
1760  *
1761  * @POST_TRIGGER: A flag that says whether or not this command needs
1762  *	to have its action delayed until after the current event has
1763  *	been closed.  Some triggers need to avoid being invoked while
1764  *	an event is currently in the process of being logged, since
1765  *	the trigger may itself log data into the trace buffer.  Thus
1766  *	we make sure the current event is committed before invoking
1767  *	those triggers.  To do that, the trigger invocation is split
1768  *	in two - the first part checks the filter using the current
1769  *	trace record; if a command has the @post_trigger flag set, it
1770  *	sets a bit for itself in the return value, otherwise it
1771  *	directly invokes the trigger.  Once all commands have been
1772  *	either invoked or set their return flag, the current record is
1773  *	either committed or discarded.  At that point, if any commands
1774  *	have deferred their triggers, those commands are finally
1775  *	invoked following the close of the current event.  In other
1776  *	words, if the event_trigger_ops @func() probe implementation
1777  *	itself logs to the trace buffer, this flag should be set,
1778  *	otherwise it can be left unspecified.
1779  *
1780  * @NEEDS_REC: A flag that says whether or not this command needs
1781  *	access to the trace record in order to perform its function,
1782  *	regardless of whether or not it has a filter associated with
1783  *	it (filters make a trigger require access to the trace record
1784  *	but are not always present).
1785  */
1786 enum event_command_flags {
1787 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1788 	EVENT_CMD_FL_NEEDS_REC		= 2,
1789 };
1790 
1791 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1792 {
1793 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1794 }
1795 
1796 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1797 {
1798 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1799 }
1800 
1801 extern int trace_event_enable_disable(struct trace_event_file *file,
1802 				      int enable, int soft_disable);
1803 extern int tracing_alloc_snapshot(void);
1804 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1805 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1806 
1807 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1808 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1809 
1810 extern const char *__start___trace_bprintk_fmt[];
1811 extern const char *__stop___trace_bprintk_fmt[];
1812 
1813 extern const char *__start___tracepoint_str[];
1814 extern const char *__stop___tracepoint_str[];
1815 
1816 void trace_printk_control(bool enabled);
1817 void trace_printk_start_comm(void);
1818 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1819 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1820 
1821 /* Used from boot time tracer */
1822 extern int trace_set_options(struct trace_array *tr, char *option);
1823 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1824 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1825 					  unsigned long size, int cpu_id);
1826 extern int tracing_set_cpumask(struct trace_array *tr,
1827 				cpumask_var_t tracing_cpumask_new);
1828 
1829 
1830 #define MAX_EVENT_NAME_LEN	64
1831 
1832 extern ssize_t trace_parse_run_command(struct file *file,
1833 		const char __user *buffer, size_t count, loff_t *ppos,
1834 		int (*createfn)(const char *));
1835 
1836 extern unsigned int err_pos(char *cmd, const char *str);
1837 extern void tracing_log_err(struct trace_array *tr,
1838 			    const char *loc, const char *cmd,
1839 			    const char **errs, u8 type, u8 pos);
1840 
1841 /*
1842  * Normal trace_printk() and friends allocates special buffers
1843  * to do the manipulation, as well as saves the print formats
1844  * into sections to display. But the trace infrastructure wants
1845  * to use these without the added overhead at the price of being
1846  * a bit slower (used mainly for warnings, where we don't care
1847  * about performance). The internal_trace_puts() is for such
1848  * a purpose.
1849  */
1850 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1851 
1852 #undef FTRACE_ENTRY
1853 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
1854 	extern struct trace_event_call					\
1855 	__aligned(4) event_##call;
1856 #undef FTRACE_ENTRY_DUP
1857 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
1858 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1859 #undef FTRACE_ENTRY_PACKED
1860 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1861 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1862 
1863 #include "trace_entries.h"
1864 
1865 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1866 int perf_ftrace_event_register(struct trace_event_call *call,
1867 			       enum trace_reg type, void *data);
1868 #else
1869 #define perf_ftrace_event_register NULL
1870 #endif
1871 
1872 #ifdef CONFIG_FTRACE_SYSCALLS
1873 void init_ftrace_syscalls(void);
1874 const char *get_syscall_name(int syscall);
1875 #else
1876 static inline void init_ftrace_syscalls(void) { }
1877 static inline const char *get_syscall_name(int syscall)
1878 {
1879 	return NULL;
1880 }
1881 #endif
1882 
1883 #ifdef CONFIG_EVENT_TRACING
1884 void trace_event_init(void);
1885 void trace_event_eval_update(struct trace_eval_map **map, int len);
1886 /* Used from boot time tracer */
1887 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1888 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1889 #else
1890 static inline void __init trace_event_init(void) { }
1891 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1892 #endif
1893 
1894 #ifdef CONFIG_TRACER_SNAPSHOT
1895 void tracing_snapshot_instance(struct trace_array *tr);
1896 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1897 #else
1898 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1899 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1900 {
1901 	return 0;
1902 }
1903 #endif
1904 
1905 #ifdef CONFIG_PREEMPT_TRACER
1906 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1907 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1908 #else
1909 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1910 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1911 #endif
1912 #ifdef CONFIG_IRQSOFF_TRACER
1913 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1914 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1915 #else
1916 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1917 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1918 #endif
1919 
1920 extern struct trace_iterator *tracepoint_print_iter;
1921 
1922 /*
1923  * Reset the state of the trace_iterator so that it can read consumed data.
1924  * Normally, the trace_iterator is used for reading the data when it is not
1925  * consumed, and must retain state.
1926  */
1927 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1928 {
1929 	const size_t offset = offsetof(struct trace_iterator, seq);
1930 
1931 	/*
1932 	 * Keep gcc from complaining about overwriting more than just one
1933 	 * member in the structure.
1934 	 */
1935 	memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1936 
1937 	iter->pos = -1;
1938 }
1939 
1940 /* Check the name is good for event/group/fields */
1941 static inline bool is_good_name(const char *name)
1942 {
1943 	if (!isalpha(*name) && *name != '_')
1944 		return false;
1945 	while (*++name != '\0') {
1946 		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1947 			return false;
1948 	}
1949 	return true;
1950 }
1951 
1952 /* Convert certain expected symbols into '_' when generating event names */
1953 static inline void sanitize_event_name(char *name)
1954 {
1955 	while (*name++ != '\0')
1956 		if (*name == ':' || *name == '.')
1957 			*name = '_';
1958 }
1959 
1960 /*
1961  * This is a generic way to read and write a u64 value from a file in tracefs.
1962  *
1963  * The value is stored on the variable pointed by *val. The value needs
1964  * to be at least *min and at most *max. The write is protected by an
1965  * existing *lock.
1966  */
1967 struct trace_min_max_param {
1968 	struct mutex	*lock;
1969 	u64		*val;
1970 	u64		*min;
1971 	u64		*max;
1972 };
1973 
1974 #define U64_STR_SIZE		24	/* 20 digits max */
1975 
1976 extern const struct file_operations trace_min_max_fops;
1977 
1978 #endif /* _LINUX_KERNEL_TRACE_H */
1979