xref: /linux/kernel/trace/trace.h (revision e20706d5385b10a6f6a2fe5ad6b1333dad2d1416)
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 #include <linux/ftrace_regs.h>
25 
26 #include "pid_list.h"
27 
28 #ifdef CONFIG_FTRACE_SYSCALLS
29 #include <asm/unistd.h>		/* For NR_syscalls	     */
30 #include <asm/syscall.h>	/* some archs define it here */
31 #endif
32 
33 #define TRACE_MODE_WRITE	0640
34 #define TRACE_MODE_READ		0440
35 
36 enum trace_type {
37 	__TRACE_FIRST_TYPE = 0,
38 
39 	TRACE_FN,
40 	TRACE_CTX,
41 	TRACE_WAKE,
42 	TRACE_STACK,
43 	TRACE_PRINT,
44 	TRACE_BPRINT,
45 	TRACE_MMIO_RW,
46 	TRACE_MMIO_MAP,
47 	TRACE_BRANCH,
48 	TRACE_GRAPH_RET,
49 	TRACE_GRAPH_ENT,
50 	TRACE_GRAPH_RETADDR_ENT,
51 	TRACE_USER_STACK,
52 	TRACE_BLK,
53 	TRACE_BPUTS,
54 	TRACE_HWLAT,
55 	TRACE_OSNOISE,
56 	TRACE_TIMERLAT,
57 	TRACE_RAW_DATA,
58 	TRACE_FUNC_REPEATS,
59 
60 	__TRACE_LAST_TYPE,
61 };
62 
63 
64 #undef __field
65 #define __field(type, item)		type	item;
66 
67 #undef __field_fn
68 #define __field_fn(type, item)		type	item;
69 
70 #undef __field_struct
71 #define __field_struct(type, item)	__field(type, item)
72 
73 #undef __field_desc
74 #define __field_desc(type, container, item)
75 
76 #undef __field_packed
77 #define __field_packed(type, container, item)
78 
79 #undef __array
80 #define __array(type, item, size)	type	item[size];
81 
82 /*
83  * For backward compatibility, older user space expects to see the
84  * kernel_stack event with a fixed size caller field. But today the fix
85  * size is ignored by the kernel, and the real structure is dynamic.
86  * Expose to user space: "unsigned long caller[8];" but the real structure
87  * will be "unsigned long caller[] __counted_by(size)"
88  */
89 #undef __stack_array
90 #define __stack_array(type, item, size, field)		type item[] __counted_by(field);
91 
92 #undef __array_desc
93 #define __array_desc(type, container, item, size)
94 
95 #undef __dynamic_array
96 #define __dynamic_array(type, item)	type	item[];
97 
98 #undef __rel_dynamic_array
99 #define __rel_dynamic_array(type, item)	type	item[];
100 
101 #undef F_STRUCT
102 #define F_STRUCT(args...)		args
103 
104 #undef FTRACE_ENTRY
105 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
106 	struct struct_name {						\
107 		struct trace_entry	ent;				\
108 		tstruct							\
109 	}
110 
111 #undef FTRACE_ENTRY_DUP
112 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
113 
114 #undef FTRACE_ENTRY_REG
115 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
116 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
117 
118 #undef FTRACE_ENTRY_PACKED
119 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
120 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
121 
122 #include "trace_entries.h"
123 
124 /* Use this for memory failure errors */
125 #define MEM_FAIL(condition, fmt, ...)					\
126 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
127 
128 #define FAULT_STRING "(fault)"
129 
130 #define HIST_STACKTRACE_DEPTH	16
131 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
132 #define HIST_STACKTRACE_SKIP	5
133 
134 /*
135  * syscalls are special, and need special handling, this is why
136  * they are not included in trace_entries.h
137  */
138 struct syscall_trace_enter {
139 	struct trace_entry	ent;
140 	int			nr;
141 	unsigned long		args[];
142 };
143 
144 struct syscall_trace_exit {
145 	struct trace_entry	ent;
146 	int			nr;
147 	long			ret;
148 };
149 
150 struct kprobe_trace_entry_head {
151 	struct trace_entry	ent;
152 	unsigned long		ip;
153 };
154 
155 struct eprobe_trace_entry_head {
156 	struct trace_entry	ent;
157 };
158 
159 struct kretprobe_trace_entry_head {
160 	struct trace_entry	ent;
161 	unsigned long		func;
162 	unsigned long		ret_ip;
163 };
164 
165 struct fentry_trace_entry_head {
166 	struct trace_entry	ent;
167 	unsigned long		ip;
168 };
169 
170 struct fexit_trace_entry_head {
171 	struct trace_entry	ent;
172 	unsigned long		func;
173 	unsigned long		ret_ip;
174 };
175 
176 #define TRACE_BUF_SIZE		1024
177 
178 struct trace_array;
179 
180 /*
181  * The CPU trace array - it consists of thousands of trace entries
182  * plus some other descriptor data: (for example which task started
183  * the trace, etc.)
184  */
185 struct trace_array_cpu {
186 	atomic_t		disabled;
187 	void			*buffer_page;	/* ring buffer spare */
188 
189 	unsigned long		entries;
190 	unsigned long		saved_latency;
191 	unsigned long		critical_start;
192 	unsigned long		critical_end;
193 	unsigned long		critical_sequence;
194 	unsigned long		nice;
195 	unsigned long		policy;
196 	unsigned long		rt_priority;
197 	unsigned long		skipped_entries;
198 	u64			preempt_timestamp;
199 	pid_t			pid;
200 	kuid_t			uid;
201 	char			comm[TASK_COMM_LEN];
202 
203 #ifdef CONFIG_FUNCTION_TRACER
204 	int			ftrace_ignore_pid;
205 #endif
206 	bool			ignore_pid;
207 };
208 
209 struct tracer;
210 struct trace_option_dentry;
211 
212 struct array_buffer {
213 	struct trace_array		*tr;
214 	struct trace_buffer		*buffer;
215 	struct trace_array_cpu __percpu	*data;
216 	u64				time_start;
217 	int				cpu;
218 };
219 
220 #define TRACE_FLAGS_MAX_SIZE		32
221 
222 struct trace_options {
223 	struct tracer			*tracer;
224 	struct trace_option_dentry	*topts;
225 };
226 
227 struct trace_pid_list *trace_pid_list_alloc(void);
228 void trace_pid_list_free(struct trace_pid_list *pid_list);
229 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
231 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
232 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
233 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
234 			unsigned int *next);
235 
236 enum {
237 	TRACE_PIDS		= BIT(0),
238 	TRACE_NO_PIDS		= BIT(1),
239 };
240 
241 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
242 				    struct trace_pid_list *no_pid_list)
243 {
244 	/* Return true if the pid list in type has pids */
245 	return ((type & TRACE_PIDS) && pid_list) ||
246 		((type & TRACE_NO_PIDS) && no_pid_list);
247 }
248 
249 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
250 					 struct trace_pid_list *no_pid_list)
251 {
252 	/*
253 	 * Turning off what is in @type, return true if the "other"
254 	 * pid list, still has pids in it.
255 	 */
256 	return (!(type & TRACE_PIDS) && pid_list) ||
257 		(!(type & TRACE_NO_PIDS) && no_pid_list);
258 }
259 
260 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
261 
262 /**
263  * struct cond_snapshot - conditional snapshot data and callback
264  *
265  * The cond_snapshot structure encapsulates a callback function and
266  * data associated with the snapshot for a given tracing instance.
267  *
268  * When a snapshot is taken conditionally, by invoking
269  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
270  * passed in turn to the cond_snapshot.update() function.  That data
271  * can be compared by the update() implementation with the cond_data
272  * contained within the struct cond_snapshot instance associated with
273  * the trace_array.  Because the tr->max_lock is held throughout the
274  * update() call, the update() function can directly retrieve the
275  * cond_snapshot and cond_data associated with the per-instance
276  * snapshot associated with the trace_array.
277  *
278  * The cond_snapshot.update() implementation can save data to be
279  * associated with the snapshot if it decides to, and returns 'true'
280  * in that case, or it returns 'false' if the conditional snapshot
281  * shouldn't be taken.
282  *
283  * The cond_snapshot instance is created and associated with the
284  * user-defined cond_data by tracing_cond_snapshot_enable().
285  * Likewise, the cond_snapshot instance is destroyed and is no longer
286  * associated with the trace instance by
287  * tracing_cond_snapshot_disable().
288  *
289  * The method below is required.
290  *
291  * @update: When a conditional snapshot is invoked, the update()
292  *	callback function is invoked with the tr->max_lock held.  The
293  *	update() implementation signals whether or not to actually
294  *	take the snapshot, by returning 'true' if so, 'false' if no
295  *	snapshot should be taken.  Because the max_lock is held for
296  *	the duration of update(), the implementation is safe to
297  *	directly retrieved and save any implementation data it needs
298  *	to in association with the snapshot.
299  */
300 struct cond_snapshot {
301 	void				*cond_data;
302 	cond_update_fn_t		update;
303 };
304 
305 /*
306  * struct trace_func_repeats - used to keep track of the consecutive
307  * (on the same CPU) calls of a single function.
308  */
309 struct trace_func_repeats {
310 	unsigned long	ip;
311 	unsigned long	parent_ip;
312 	unsigned long	count;
313 	u64		ts_last_call;
314 };
315 
316 struct trace_module_delta {
317 	struct rcu_head	rcu;
318 	long		delta[];
319 };
320 
321 /*
322  * The trace array - an array of per-CPU trace arrays. This is the
323  * highest level data structure that individual tracers deal with.
324  * They have on/off state as well:
325  */
326 struct trace_array {
327 	struct list_head	list;
328 	char			*name;
329 	struct array_buffer	array_buffer;
330 #ifdef CONFIG_TRACER_MAX_TRACE
331 	/*
332 	 * The max_buffer is used to snapshot the trace when a maximum
333 	 * latency is reached, or when the user initiates a snapshot.
334 	 * Some tracers will use this to store a maximum trace while
335 	 * it continues examining live traces.
336 	 *
337 	 * The buffers for the max_buffer are set up the same as the array_buffer
338 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
339 	 * with the buffer of the array_buffer and the buffers are reset for
340 	 * the array_buffer so the tracing can continue.
341 	 */
342 	struct array_buffer	max_buffer;
343 	bool			allocated_snapshot;
344 	spinlock_t		snapshot_trigger_lock;
345 	unsigned int		snapshot;
346 	unsigned long		max_latency;
347 #ifdef CONFIG_FSNOTIFY
348 	struct dentry		*d_max_latency;
349 	struct work_struct	fsnotify_work;
350 	struct irq_work		fsnotify_irqwork;
351 #endif
352 #endif
353 	/* The below is for memory mapped ring buffer */
354 	unsigned int		mapped;
355 	unsigned long		range_addr_start;
356 	unsigned long		range_addr_size;
357 	char			*range_name;
358 	long			text_delta;
359 	struct trace_module_delta *module_delta;
360 	void			*scratch; /* pointer in persistent memory */
361 	int			scratch_size;
362 
363 	int			buffer_disabled;
364 
365 	struct trace_pid_list	__rcu *filtered_pids;
366 	struct trace_pid_list	__rcu *filtered_no_pids;
367 	/*
368 	 * max_lock is used to protect the swapping of buffers
369 	 * when taking a max snapshot. The buffers themselves are
370 	 * protected by per_cpu spinlocks. But the action of the swap
371 	 * needs its own lock.
372 	 *
373 	 * This is defined as a arch_spinlock_t in order to help
374 	 * with performance when lockdep debugging is enabled.
375 	 *
376 	 * It is also used in other places outside the update_max_tr
377 	 * so it needs to be defined outside of the
378 	 * CONFIG_TRACER_MAX_TRACE.
379 	 */
380 	arch_spinlock_t		max_lock;
381 #ifdef CONFIG_FTRACE_SYSCALLS
382 	int			sys_refcount_enter;
383 	int			sys_refcount_exit;
384 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
385 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
386 #endif
387 	int			stop_count;
388 	int			clock_id;
389 	int			nr_topts;
390 	bool			clear_trace;
391 	int			buffer_percent;
392 	unsigned int		n_err_log_entries;
393 	struct tracer		*current_trace;
394 	unsigned int		trace_flags;
395 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
396 	unsigned int		flags;
397 	raw_spinlock_t		start_lock;
398 	const char		*system_names;
399 	struct list_head	err_log;
400 	struct dentry		*dir;
401 	struct dentry		*options;
402 	struct dentry		*percpu_dir;
403 	struct eventfs_inode	*event_dir;
404 	struct trace_options	*topts;
405 	struct list_head	systems;
406 	struct list_head	events;
407 	struct trace_event_file *trace_marker_file;
408 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
409 	/* one per_cpu trace_pipe can be opened by only one user */
410 	cpumask_var_t		pipe_cpumask;
411 	int			ref;
412 	int			trace_ref;
413 #ifdef CONFIG_MODULES
414 	struct list_head	mod_events;
415 #endif
416 #ifdef CONFIG_FUNCTION_TRACER
417 	struct ftrace_ops	*ops;
418 	struct trace_pid_list	__rcu *function_pids;
419 	struct trace_pid_list	__rcu *function_no_pids;
420 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
421 	struct fgraph_ops	*gops;
422 #endif
423 #ifdef CONFIG_DYNAMIC_FTRACE
424 	/* All of these are protected by the ftrace_lock */
425 	struct list_head	func_probes;
426 	struct list_head	mod_trace;
427 	struct list_head	mod_notrace;
428 #endif
429 	/* function tracing enabled */
430 	int			function_enabled;
431 #endif
432 	int			no_filter_buffering_ref;
433 	struct list_head	hist_vars;
434 #ifdef CONFIG_TRACER_SNAPSHOT
435 	struct cond_snapshot	*cond_snapshot;
436 #endif
437 	struct trace_func_repeats	__percpu *last_func_repeats;
438 	/*
439 	 * On boot up, the ring buffer is set to the minimum size, so that
440 	 * we do not waste memory on systems that are not using tracing.
441 	 */
442 	bool ring_buffer_expanded;
443 };
444 
445 enum {
446 	TRACE_ARRAY_FL_GLOBAL		= BIT(0),
447 	TRACE_ARRAY_FL_BOOT		= BIT(1),
448 	TRACE_ARRAY_FL_LAST_BOOT	= BIT(2),
449 	TRACE_ARRAY_FL_MOD_INIT		= BIT(3),
450 };
451 
452 #ifdef CONFIG_MODULES
453 bool module_exists(const char *module);
454 #else
455 static inline bool module_exists(const char *module)
456 {
457 	return false;
458 }
459 #endif
460 
461 extern struct list_head ftrace_trace_arrays;
462 
463 extern struct mutex trace_types_lock;
464 
465 extern int trace_array_get(struct trace_array *tr);
466 extern int tracing_check_open_get_tr(struct trace_array *tr);
467 extern struct trace_array *trace_array_find(const char *instance);
468 extern struct trace_array *trace_array_find_get(const char *instance);
469 
470 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
471 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
472 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
473 
474 extern bool trace_clock_in_ns(struct trace_array *tr);
475 
476 extern unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr);
477 
478 /*
479  * The global tracer (top) should be the first trace array added,
480  * but we check the flag anyway.
481  */
482 static inline struct trace_array *top_trace_array(void)
483 {
484 	struct trace_array *tr;
485 
486 	if (list_empty(&ftrace_trace_arrays))
487 		return NULL;
488 
489 	tr = list_entry(ftrace_trace_arrays.prev,
490 			typeof(*tr), list);
491 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
492 	return tr;
493 }
494 
495 #define FTRACE_CMP_TYPE(var, type) \
496 	__builtin_types_compatible_p(typeof(var), type *)
497 
498 #undef IF_ASSIGN
499 #define IF_ASSIGN(var, entry, etype, id)			\
500 	if (FTRACE_CMP_TYPE(var, etype)) {			\
501 		var = (typeof(var))(entry);			\
502 		WARN_ON(id != 0 && (entry)->type != id);	\
503 		break;						\
504 	}
505 
506 /* Will cause compile errors if type is not found. */
507 extern void __ftrace_bad_type(void);
508 
509 /*
510  * The trace_assign_type is a verifier that the entry type is
511  * the same as the type being assigned. To add new types simply
512  * add a line with the following format:
513  *
514  * IF_ASSIGN(var, ent, type, id);
515  *
516  *  Where "type" is the trace type that includes the trace_entry
517  *  as the "ent" item. And "id" is the trace identifier that is
518  *  used in the trace_type enum.
519  *
520  *  If the type can have more than one id, then use zero.
521  */
522 #define trace_assign_type(var, ent)					\
523 	do {								\
524 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
525 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
526 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
527 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
528 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
529 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
530 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
531 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
532 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
533 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
534 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
535 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
536 			  TRACE_MMIO_RW);				\
537 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
538 			  TRACE_MMIO_MAP);				\
539 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
540 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
541 			  TRACE_GRAPH_ENT);		\
542 		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
543 			  TRACE_GRAPH_RETADDR_ENT);		\
544 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
545 			  TRACE_GRAPH_RET);		\
546 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
547 			  TRACE_FUNC_REPEATS);				\
548 		__ftrace_bad_type();					\
549 	} while (0)
550 
551 /*
552  * An option specific to a tracer. This is a boolean value.
553  * The bit is the bit index that sets its value on the
554  * flags value in struct tracer_flags.
555  */
556 struct tracer_opt {
557 	const char	*name; /* Will appear on the trace_options file */
558 	u32		bit; /* Mask assigned in val field in tracer_flags */
559 };
560 
561 /*
562  * The set of specific options for a tracer. Your tracer
563  * have to set the initial value of the flags val.
564  */
565 struct tracer_flags {
566 	u32			val;
567 	struct tracer_opt	*opts;
568 	struct tracer		*trace;
569 };
570 
571 /* Makes more easy to define a tracer opt */
572 #define TRACER_OPT(s, b)	.name = #s, .bit = b
573 
574 
575 struct trace_option_dentry {
576 	struct tracer_opt		*opt;
577 	struct tracer_flags		*flags;
578 	struct trace_array		*tr;
579 	struct dentry			*entry;
580 };
581 
582 /**
583  * struct tracer - a specific tracer and its callbacks to interact with tracefs
584  * @name: the name chosen to select it on the available_tracers file
585  * @init: called when one switches to this tracer (echo name > current_tracer)
586  * @reset: called when one switches to another tracer
587  * @start: called when tracing is unpaused (echo 1 > tracing_on)
588  * @stop: called when tracing is paused (echo 0 > tracing_on)
589  * @update_thresh: called when tracing_thresh is updated
590  * @open: called when the trace file is opened
591  * @pipe_open: called when the trace_pipe file is opened
592  * @close: called when the trace file is released
593  * @pipe_close: called when the trace_pipe file is released
594  * @read: override the default read callback on trace_pipe
595  * @splice_read: override the default splice_read callback on trace_pipe
596  * @selftest: selftest to run on boot (see trace_selftest.c)
597  * @print_headers: override the first lines that describe your columns
598  * @print_line: callback that prints a trace
599  * @set_flag: signals one of your private flags changed (trace_options file)
600  * @flags: your private flags
601  */
602 struct tracer {
603 	const char		*name;
604 	int			(*init)(struct trace_array *tr);
605 	void			(*reset)(struct trace_array *tr);
606 	void			(*start)(struct trace_array *tr);
607 	void			(*stop)(struct trace_array *tr);
608 	int			(*update_thresh)(struct trace_array *tr);
609 	void			(*open)(struct trace_iterator *iter);
610 	void			(*pipe_open)(struct trace_iterator *iter);
611 	void			(*close)(struct trace_iterator *iter);
612 	void			(*pipe_close)(struct trace_iterator *iter);
613 	ssize_t			(*read)(struct trace_iterator *iter,
614 					struct file *filp, char __user *ubuf,
615 					size_t cnt, loff_t *ppos);
616 	ssize_t			(*splice_read)(struct trace_iterator *iter,
617 					       struct file *filp,
618 					       loff_t *ppos,
619 					       struct pipe_inode_info *pipe,
620 					       size_t len,
621 					       unsigned int flags);
622 #ifdef CONFIG_FTRACE_STARTUP_TEST
623 	int			(*selftest)(struct tracer *trace,
624 					    struct trace_array *tr);
625 #endif
626 	void			(*print_header)(struct seq_file *m);
627 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
628 	/* If you handled the flag setting, return 0 */
629 	int			(*set_flag)(struct trace_array *tr,
630 					    u32 old_flags, u32 bit, int set);
631 	/* Return 0 if OK with change, else return non-zero */
632 	int			(*flag_changed)(struct trace_array *tr,
633 						u32 mask, int set);
634 	struct tracer		*next;
635 	struct tracer_flags	*flags;
636 	int			enabled;
637 	bool			print_max;
638 	bool			allow_instances;
639 #ifdef CONFIG_TRACER_MAX_TRACE
640 	bool			use_max_tr;
641 #endif
642 	/* True if tracer cannot be enabled in kernel param */
643 	bool			noboot;
644 };
645 
646 static inline struct ring_buffer_iter *
647 trace_buffer_iter(struct trace_iterator *iter, int cpu)
648 {
649 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
650 }
651 
652 int tracer_init(struct tracer *t, struct trace_array *tr);
653 int tracing_is_enabled(void);
654 void tracing_reset_online_cpus(struct array_buffer *buf);
655 void tracing_reset_all_online_cpus(void);
656 void tracing_reset_all_online_cpus_unlocked(void);
657 int tracing_open_generic(struct inode *inode, struct file *filp);
658 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
659 int tracing_release_generic_tr(struct inode *inode, struct file *file);
660 int tracing_open_file_tr(struct inode *inode, struct file *filp);
661 int tracing_release_file_tr(struct inode *inode, struct file *filp);
662 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
663 bool tracing_is_disabled(void);
664 bool tracer_tracing_is_on(struct trace_array *tr);
665 void tracer_tracing_on(struct trace_array *tr);
666 void tracer_tracing_off(struct trace_array *tr);
667 struct dentry *trace_create_file(const char *name,
668 				 umode_t mode,
669 				 struct dentry *parent,
670 				 void *data,
671 				 const struct file_operations *fops);
672 
673 int tracing_init_dentry(void);
674 
675 struct ring_buffer_event;
676 
677 struct ring_buffer_event *
678 trace_buffer_lock_reserve(struct trace_buffer *buffer,
679 			  int type,
680 			  unsigned long len,
681 			  unsigned int trace_ctx);
682 
683 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
684 
685 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
686 						struct trace_array_cpu *data);
687 
688 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
689 					  int *ent_cpu, u64 *ent_ts);
690 
691 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
692 					struct ring_buffer_event *event);
693 
694 bool trace_is_tracepoint_string(const char *str);
695 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
696 char *trace_iter_expand_format(struct trace_iterator *iter);
697 bool ignore_event(struct trace_iterator *iter);
698 
699 int trace_empty(struct trace_iterator *iter);
700 
701 void *trace_find_next_entry_inc(struct trace_iterator *iter);
702 
703 void trace_init_global_iter(struct trace_iterator *iter);
704 
705 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
706 
707 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
708 unsigned long trace_total_entries(struct trace_array *tr);
709 
710 void trace_function(struct trace_array *tr,
711 		    unsigned long ip,
712 		    unsigned long parent_ip,
713 		    unsigned int trace_ctx,
714 		    struct ftrace_regs *regs);
715 void trace_graph_function(struct trace_array *tr,
716 		    unsigned long ip,
717 		    unsigned long parent_ip,
718 		    unsigned int trace_ctx);
719 void trace_latency_header(struct seq_file *m);
720 void trace_default_header(struct seq_file *m);
721 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
722 
723 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
724 			struct ftrace_regs *fregs);
725 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
726 		      struct ftrace_regs *fregs);
727 
728 void tracing_start_cmdline_record(void);
729 void tracing_stop_cmdline_record(void);
730 void tracing_start_tgid_record(void);
731 void tracing_stop_tgid_record(void);
732 
733 int register_tracer(struct tracer *type);
734 int is_tracing_stopped(void);
735 
736 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
737 
738 extern cpumask_var_t __read_mostly tracing_buffer_mask;
739 
740 #define for_each_tracing_cpu(cpu)	\
741 	for_each_cpu(cpu, tracing_buffer_mask)
742 
743 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
744 
745 extern unsigned long tracing_thresh;
746 
747 /* PID filtering */
748 
749 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
750 			     pid_t search_pid);
751 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
752 			    struct trace_pid_list *filtered_no_pids,
753 			    struct task_struct *task);
754 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
755 				  struct task_struct *self,
756 				  struct task_struct *task);
757 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
758 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
759 int trace_pid_show(struct seq_file *m, void *v);
760 int trace_pid_write(struct trace_pid_list *filtered_pids,
761 		    struct trace_pid_list **new_pid_list,
762 		    const char __user *ubuf, size_t cnt);
763 
764 #ifdef CONFIG_TRACER_MAX_TRACE
765 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
766 		   void *cond_data);
767 void update_max_tr_single(struct trace_array *tr,
768 			  struct task_struct *tsk, int cpu);
769 
770 #ifdef CONFIG_FSNOTIFY
771 #define LATENCY_FS_NOTIFY
772 #endif
773 #endif /* CONFIG_TRACER_MAX_TRACE */
774 
775 #ifdef LATENCY_FS_NOTIFY
776 void latency_fsnotify(struct trace_array *tr);
777 #else
778 static inline void latency_fsnotify(struct trace_array *tr) { }
779 #endif
780 
781 #ifdef CONFIG_STACKTRACE
782 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
783 #else
784 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
785 				 int skip)
786 {
787 }
788 #endif /* CONFIG_STACKTRACE */
789 
790 void trace_last_func_repeats(struct trace_array *tr,
791 			     struct trace_func_repeats *last_info,
792 			     unsigned int trace_ctx);
793 
794 extern u64 ftrace_now(int cpu);
795 
796 extern void trace_find_cmdline(int pid, char comm[]);
797 extern int trace_find_tgid(int pid);
798 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
799 
800 extern int trace_events_enabled(struct trace_array *tr, const char *system);
801 
802 #ifdef CONFIG_DYNAMIC_FTRACE
803 extern unsigned long ftrace_update_tot_cnt;
804 extern unsigned long ftrace_number_of_pages;
805 extern unsigned long ftrace_number_of_groups;
806 extern u64 ftrace_update_time;
807 extern u64 ftrace_total_mod_time;
808 void ftrace_init_trace_array(struct trace_array *tr);
809 #else
810 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
811 #endif
812 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
813 extern int DYN_FTRACE_TEST_NAME(void);
814 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
815 extern int DYN_FTRACE_TEST_NAME2(void);
816 
817 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
818 extern bool tracing_selftest_disabled;
819 
820 #ifdef CONFIG_FTRACE_STARTUP_TEST
821 extern void __init disable_tracing_selftest(const char *reason);
822 
823 extern int trace_selftest_startup_function(struct tracer *trace,
824 					   struct trace_array *tr);
825 extern int trace_selftest_startup_function_graph(struct tracer *trace,
826 						 struct trace_array *tr);
827 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
828 					  struct trace_array *tr);
829 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
830 					     struct trace_array *tr);
831 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
832 						 struct trace_array *tr);
833 extern int trace_selftest_startup_wakeup(struct tracer *trace,
834 					 struct trace_array *tr);
835 extern int trace_selftest_startup_nop(struct tracer *trace,
836 					 struct trace_array *tr);
837 extern int trace_selftest_startup_branch(struct tracer *trace,
838 					 struct trace_array *tr);
839 /*
840  * Tracer data references selftest functions that only occur
841  * on boot up. These can be __init functions. Thus, when selftests
842  * are enabled, then the tracers need to reference __init functions.
843  */
844 #define __tracer_data		__refdata
845 #else
846 static inline void __init disable_tracing_selftest(const char *reason)
847 {
848 }
849 /* Tracers are seldom changed. Optimize when selftests are disabled. */
850 #define __tracer_data		__read_mostly
851 #endif /* CONFIG_FTRACE_STARTUP_TEST */
852 
853 extern void *head_page(struct trace_array_cpu *data);
854 extern unsigned long long ns2usecs(u64 nsec);
855 extern int
856 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
857 extern int
858 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
859 extern int
860 trace_array_vprintk(struct trace_array *tr,
861 		    unsigned long ip, const char *fmt, va_list args);
862 int trace_array_printk_buf(struct trace_buffer *buffer,
863 			   unsigned long ip, const char *fmt, ...);
864 void trace_printk_seq(struct trace_seq *s);
865 enum print_line_t print_trace_line(struct trace_iterator *iter);
866 
867 extern char trace_find_mark(unsigned long long duration);
868 
869 struct ftrace_hash;
870 
871 struct ftrace_mod_load {
872 	struct list_head	list;
873 	char			*func;
874 	char			*module;
875 	int			 enable;
876 };
877 
878 enum {
879 	FTRACE_HASH_FL_MOD	= (1 << 0),
880 };
881 
882 struct ftrace_hash {
883 	unsigned long		size_bits;
884 	struct hlist_head	*buckets;
885 	unsigned long		count;
886 	unsigned long		flags;
887 	struct rcu_head		rcu;
888 };
889 
890 struct ftrace_func_entry *
891 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
892 
893 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
894 {
895 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
896 }
897 
898 /* Standard output formatting function used for function return traces */
899 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
900 
901 /* Flag options */
902 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
903 #define TRACE_GRAPH_PRINT_CPU           0x2
904 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
905 #define TRACE_GRAPH_PRINT_PROC          0x8
906 #define TRACE_GRAPH_PRINT_DURATION      0x10
907 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
908 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
909 #define TRACE_GRAPH_PRINT_IRQS          0x80
910 #define TRACE_GRAPH_PRINT_TAIL          0x100
911 #define TRACE_GRAPH_SLEEP_TIME          0x200
912 #define TRACE_GRAPH_GRAPH_TIME          0x400
913 #define TRACE_GRAPH_PRINT_RETVAL        0x800
914 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
915 #define TRACE_GRAPH_PRINT_RETADDR       0x2000
916 #define TRACE_GRAPH_ARGS		0x4000
917 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
918 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
919 
920 extern void ftrace_graph_sleep_time_control(bool enable);
921 
922 #ifdef CONFIG_FUNCTION_PROFILER
923 extern void ftrace_graph_graph_time_control(bool enable);
924 #else
925 static inline void ftrace_graph_graph_time_control(bool enable) { }
926 #endif
927 
928 extern enum print_line_t
929 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
930 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
931 extern void
932 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
933 extern void graph_trace_open(struct trace_iterator *iter);
934 extern void graph_trace_close(struct trace_iterator *iter);
935 extern int __trace_graph_entry(struct trace_array *tr,
936 			       struct ftrace_graph_ent *trace,
937 			       unsigned int trace_ctx);
938 extern int __trace_graph_retaddr_entry(struct trace_array *tr,
939 				struct ftrace_graph_ent *trace,
940 				unsigned int trace_ctx,
941 				unsigned long retaddr);
942 extern void __trace_graph_return(struct trace_array *tr,
943 				 struct ftrace_graph_ret *trace,
944 				 unsigned int trace_ctx,
945 				 u64 calltime, u64 rettime);
946 
947 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
948 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
949 extern void free_fgraph_ops(struct trace_array *tr);
950 
951 enum {
952 	TRACE_GRAPH_FL		= 1,
953 
954 	/*
955 	 * In the very unlikely case that an interrupt came in
956 	 * at a start of graph tracing, and we want to trace
957 	 * the function in that interrupt, the depth can be greater
958 	 * than zero, because of the preempted start of a previous
959 	 * trace. In an even more unlikely case, depth could be 2
960 	 * if a softirq interrupted the start of graph tracing,
961 	 * followed by an interrupt preempting a start of graph
962 	 * tracing in the softirq, and depth can even be 3
963 	 * if an NMI came in at the start of an interrupt function
964 	 * that preempted a softirq start of a function that
965 	 * preempted normal context!!!! Luckily, it can't be
966 	 * greater than 3, so the next two bits are a mask
967 	 * of what the depth is when we set TRACE_GRAPH_FL
968 	 */
969 
970 	TRACE_GRAPH_DEPTH_START_BIT,
971 	TRACE_GRAPH_DEPTH_END_BIT,
972 
973 	/*
974 	 * To implement set_graph_notrace, if this bit is set, we ignore
975 	 * function graph tracing of called functions, until the return
976 	 * function is called to clear it.
977 	 */
978 	TRACE_GRAPH_NOTRACE_BIT,
979 };
980 
981 #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
982 
983 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
984 {
985 	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
986 }
987 
988 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
989 {
990 	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
991 	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
992 }
993 
994 #ifdef CONFIG_DYNAMIC_FTRACE
995 extern struct ftrace_hash __rcu *ftrace_graph_hash;
996 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
997 
998 static inline int
999 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1000 {
1001 	unsigned long addr = trace->func;
1002 	int ret = 0;
1003 	struct ftrace_hash *hash;
1004 
1005 	preempt_disable_notrace();
1006 
1007 	/*
1008 	 * Have to open code "rcu_dereference_sched()" because the
1009 	 * function graph tracer can be called when RCU is not
1010 	 * "watching".
1011 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1012 	 */
1013 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
1014 
1015 	if (ftrace_hash_empty(hash)) {
1016 		ret = 1;
1017 		goto out;
1018 	}
1019 
1020 	if (ftrace_lookup_ip(hash, addr)) {
1021 		/*
1022 		 * This needs to be cleared on the return functions
1023 		 * when the depth is zero.
1024 		 */
1025 		*task_var |= TRACE_GRAPH_FL;
1026 		ftrace_graph_set_depth(task_var, trace->depth);
1027 
1028 		/*
1029 		 * If no irqs are to be traced, but a set_graph_function
1030 		 * is set, and called by an interrupt handler, we still
1031 		 * want to trace it.
1032 		 */
1033 		if (in_hardirq())
1034 			trace_recursion_set(TRACE_IRQ_BIT);
1035 		else
1036 			trace_recursion_clear(TRACE_IRQ_BIT);
1037 		ret = 1;
1038 	}
1039 
1040 out:
1041 	preempt_enable_notrace();
1042 	return ret;
1043 }
1044 
1045 static inline void
1046 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1047 {
1048 	unsigned long *task_var = fgraph_get_task_var(gops);
1049 
1050 	if ((*task_var & TRACE_GRAPH_FL) &&
1051 	    trace->depth == ftrace_graph_depth(task_var))
1052 		*task_var &= ~TRACE_GRAPH_FL;
1053 }
1054 
1055 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1056 {
1057 	int ret = 0;
1058 	struct ftrace_hash *notrace_hash;
1059 
1060 	preempt_disable_notrace();
1061 
1062 	/*
1063 	 * Have to open code "rcu_dereference_sched()" because the
1064 	 * function graph tracer can be called when RCU is not
1065 	 * "watching".
1066 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1067 	 */
1068 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1069 						 !preemptible());
1070 
1071 	if (ftrace_lookup_ip(notrace_hash, addr))
1072 		ret = 1;
1073 
1074 	preempt_enable_notrace();
1075 	return ret;
1076 }
1077 #else
1078 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1079 {
1080 	return 1;
1081 }
1082 
1083 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1084 {
1085 	return 0;
1086 }
1087 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1088 { }
1089 #endif /* CONFIG_DYNAMIC_FTRACE */
1090 
1091 extern unsigned int fgraph_max_depth;
1092 extern bool fgraph_sleep_time;
1093 
1094 static inline bool
1095 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1096 {
1097 	unsigned long *task_var = fgraph_get_task_var(gops);
1098 
1099 	/* trace it when it is-nested-in or is a function enabled. */
1100 	return !((*task_var & TRACE_GRAPH_FL) ||
1101 		 ftrace_graph_addr(task_var, trace)) ||
1102 		(trace->depth < 0) ||
1103 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1104 }
1105 
1106 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1107 		     struct ftrace_ops *src_ops);
1108 
1109 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1110 static inline enum print_line_t
1111 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1112 {
1113 	return TRACE_TYPE_UNHANDLED;
1114 }
1115 static inline void free_fgraph_ops(struct trace_array *tr) { }
1116 /* ftrace_ops may not be defined */
1117 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1118 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1119 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1120 
1121 extern struct list_head ftrace_pids;
1122 
1123 #ifdef CONFIG_FUNCTION_TRACER
1124 
1125 #define FTRACE_PID_IGNORE	-1
1126 #define FTRACE_PID_TRACE	-2
1127 
1128 struct ftrace_func_command {
1129 	struct list_head	list;
1130 	char			*name;
1131 	int			(*func)(struct trace_array *tr,
1132 					struct ftrace_hash *hash,
1133 					char *func, char *cmd,
1134 					char *params, int enable);
1135 };
1136 extern bool ftrace_filter_param __initdata;
1137 static inline int ftrace_trace_task(struct trace_array *tr)
1138 {
1139 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1140 		FTRACE_PID_IGNORE;
1141 }
1142 extern int ftrace_is_dead(void);
1143 int ftrace_create_function_files(struct trace_array *tr,
1144 				 struct dentry *parent);
1145 void ftrace_destroy_function_files(struct trace_array *tr);
1146 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1147 void ftrace_free_ftrace_ops(struct trace_array *tr);
1148 void ftrace_init_global_array_ops(struct trace_array *tr);
1149 struct trace_array *trace_get_global_array(void);
1150 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1151 void ftrace_reset_array_ops(struct trace_array *tr);
1152 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1153 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1154 				  struct dentry *d_tracer);
1155 void ftrace_clear_pids(struct trace_array *tr);
1156 int init_function_trace(void);
1157 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1158 #else
1159 static inline int ftrace_trace_task(struct trace_array *tr)
1160 {
1161 	return 1;
1162 }
1163 static inline int ftrace_is_dead(void) { return 0; }
1164 static inline int
1165 ftrace_create_function_files(struct trace_array *tr,
1166 			     struct dentry *parent)
1167 {
1168 	return 0;
1169 }
1170 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1171 {
1172 	return 0;
1173 }
1174 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1175 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1176 static inline __init void
1177 ftrace_init_global_array_ops(struct trace_array *tr) { }
1178 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1179 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1180 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1181 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1182 static inline int init_function_trace(void) { return 0; }
1183 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1184 /* ftace_func_t type is not defined, use macro instead of static inline */
1185 #define ftrace_init_array_ops(tr, func) do { } while (0)
1186 #endif /* CONFIG_FUNCTION_TRACER */
1187 
1188 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1189 
1190 struct ftrace_probe_ops {
1191 	void			(*func)(unsigned long ip,
1192 					unsigned long parent_ip,
1193 					struct trace_array *tr,
1194 					struct ftrace_probe_ops *ops,
1195 					void *data);
1196 	int			(*init)(struct ftrace_probe_ops *ops,
1197 					struct trace_array *tr,
1198 					unsigned long ip, void *init_data,
1199 					void **data);
1200 	void			(*free)(struct ftrace_probe_ops *ops,
1201 					struct trace_array *tr,
1202 					unsigned long ip, void *data);
1203 	int			(*print)(struct seq_file *m,
1204 					 unsigned long ip,
1205 					 struct ftrace_probe_ops *ops,
1206 					 void *data);
1207 };
1208 
1209 struct ftrace_func_mapper;
1210 typedef int (*ftrace_mapper_func)(void *data);
1211 
1212 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1213 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1214 					   unsigned long ip);
1215 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1216 			       unsigned long ip, void *data);
1217 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1218 				   unsigned long ip);
1219 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1220 			     ftrace_mapper_func free_func);
1221 
1222 extern int
1223 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1224 			       struct ftrace_probe_ops *ops, void *data);
1225 extern int
1226 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1227 				      struct ftrace_probe_ops *ops);
1228 extern void clear_ftrace_function_probes(struct trace_array *tr);
1229 
1230 int register_ftrace_command(struct ftrace_func_command *cmd);
1231 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1232 
1233 void ftrace_create_filter_files(struct ftrace_ops *ops,
1234 				struct dentry *parent);
1235 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1236 
1237 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1238 			     int len, int reset);
1239 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1240 			      int len, int reset);
1241 #else
1242 struct ftrace_func_command;
1243 
1244 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1245 {
1246 	return -EINVAL;
1247 }
1248 static inline __init int unregister_ftrace_command(char *cmd_name)
1249 {
1250 	return -EINVAL;
1251 }
1252 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1253 {
1254 }
1255 
1256 /*
1257  * The ops parameter passed in is usually undefined.
1258  * This must be a macro.
1259  */
1260 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1261 #define ftrace_destroy_filter_files(ops) do { } while (0)
1262 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1263 
1264 bool ftrace_event_is_function(struct trace_event_call *call);
1265 
1266 /*
1267  * struct trace_parser - servers for reading the user input separated by spaces
1268  * @cont: set if the input is not complete - no final space char was found
1269  * @buffer: holds the parsed user input
1270  * @idx: user input length
1271  * @size: buffer size
1272  */
1273 struct trace_parser {
1274 	bool		cont;
1275 	char		*buffer;
1276 	unsigned	idx;
1277 	unsigned	size;
1278 };
1279 
1280 static inline bool trace_parser_loaded(struct trace_parser *parser)
1281 {
1282 	return (parser->idx != 0);
1283 }
1284 
1285 static inline bool trace_parser_cont(struct trace_parser *parser)
1286 {
1287 	return parser->cont;
1288 }
1289 
1290 static inline void trace_parser_clear(struct trace_parser *parser)
1291 {
1292 	parser->cont = false;
1293 	parser->idx = 0;
1294 }
1295 
1296 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1297 extern void trace_parser_put(struct trace_parser *parser);
1298 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1299 	size_t cnt, loff_t *ppos);
1300 
1301 /*
1302  * Only create function graph options if function graph is configured.
1303  */
1304 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1305 # define FGRAPH_FLAGS						\
1306 		C(DISPLAY_GRAPH,	"display-graph"),
1307 #else
1308 # define FGRAPH_FLAGS
1309 #endif
1310 
1311 #ifdef CONFIG_BRANCH_TRACER
1312 # define BRANCH_FLAGS					\
1313 		C(BRANCH,		"branch"),
1314 #else
1315 # define BRANCH_FLAGS
1316 #endif
1317 
1318 #ifdef CONFIG_FUNCTION_TRACER
1319 # define FUNCTION_FLAGS						\
1320 		C(FUNCTION,		"function-trace"),	\
1321 		C(FUNC_FORK,		"function-fork"),
1322 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1323 #else
1324 # define FUNCTION_FLAGS
1325 # define FUNCTION_DEFAULT_FLAGS		0UL
1326 # define TRACE_ITER_FUNC_FORK		0UL
1327 #endif
1328 
1329 #ifdef CONFIG_STACKTRACE
1330 # define STACK_FLAGS				\
1331 		C(STACKTRACE,		"stacktrace"),
1332 #else
1333 # define STACK_FLAGS
1334 #endif
1335 
1336 /*
1337  * trace_iterator_flags is an enumeration that defines bit
1338  * positions into trace_flags that controls the output.
1339  *
1340  * NOTE: These bits must match the trace_options array in
1341  *       trace.c (this macro guarantees it).
1342  */
1343 #define TRACE_FLAGS						\
1344 		C(PRINT_PARENT,		"print-parent"),	\
1345 		C(SYM_OFFSET,		"sym-offset"),		\
1346 		C(SYM_ADDR,		"sym-addr"),		\
1347 		C(VERBOSE,		"verbose"),		\
1348 		C(RAW,			"raw"),			\
1349 		C(HEX,			"hex"),			\
1350 		C(BIN,			"bin"),			\
1351 		C(BLOCK,		"block"),		\
1352 		C(FIELDS,		"fields"),		\
1353 		C(PRINTK,		"trace_printk"),	\
1354 		C(ANNOTATE,		"annotate"),		\
1355 		C(USERSTACKTRACE,	"userstacktrace"),	\
1356 		C(SYM_USEROBJ,		"sym-userobj"),		\
1357 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1358 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1359 		C(LATENCY_FMT,		"latency-format"),	\
1360 		C(RECORD_CMD,		"record-cmd"),		\
1361 		C(RECORD_TGID,		"record-tgid"),		\
1362 		C(OVERWRITE,		"overwrite"),		\
1363 		C(STOP_ON_FREE,		"disable_on_free"),	\
1364 		C(IRQ_INFO,		"irq-info"),		\
1365 		C(MARKERS,		"markers"),		\
1366 		C(EVENT_FORK,		"event-fork"),		\
1367 		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1368 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1369 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1370 		FUNCTION_FLAGS					\
1371 		FGRAPH_FLAGS					\
1372 		STACK_FLAGS					\
1373 		BRANCH_FLAGS
1374 
1375 /*
1376  * By defining C, we can make TRACE_FLAGS a list of bit names
1377  * that will define the bits for the flag masks.
1378  */
1379 #undef C
1380 #define C(a, b) TRACE_ITER_##a##_BIT
1381 
1382 enum trace_iterator_bits {
1383 	TRACE_FLAGS
1384 	/* Make sure we don't go more than we have bits for */
1385 	TRACE_ITER_LAST_BIT
1386 };
1387 
1388 /*
1389  * By redefining C, we can make TRACE_FLAGS a list of masks that
1390  * use the bits as defined above.
1391  */
1392 #undef C
1393 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1394 
1395 enum trace_iterator_flags { TRACE_FLAGS };
1396 
1397 /*
1398  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1399  * control the output of kernel symbols.
1400  */
1401 #define TRACE_ITER_SYM_MASK \
1402 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1403 
1404 extern struct tracer nop_trace;
1405 
1406 #ifdef CONFIG_BRANCH_TRACER
1407 extern int enable_branch_tracing(struct trace_array *tr);
1408 extern void disable_branch_tracing(void);
1409 static inline int trace_branch_enable(struct trace_array *tr)
1410 {
1411 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1412 		return enable_branch_tracing(tr);
1413 	return 0;
1414 }
1415 static inline void trace_branch_disable(void)
1416 {
1417 	/* due to races, always disable */
1418 	disable_branch_tracing();
1419 }
1420 #else
1421 static inline int trace_branch_enable(struct trace_array *tr)
1422 {
1423 	return 0;
1424 }
1425 static inline void trace_branch_disable(void)
1426 {
1427 }
1428 #endif /* CONFIG_BRANCH_TRACER */
1429 
1430 /* set ring buffers to default size if not already done so */
1431 int tracing_update_buffers(struct trace_array *tr);
1432 
1433 union trace_synth_field {
1434 	u8				as_u8;
1435 	u16				as_u16;
1436 	u32				as_u32;
1437 	u64				as_u64;
1438 	struct trace_dynamic_info	as_dynamic;
1439 };
1440 
1441 struct ftrace_event_field {
1442 	struct list_head	link;
1443 	const char		*name;
1444 	const char		*type;
1445 	int			filter_type;
1446 	int			offset;
1447 	int			size;
1448 	unsigned int		is_signed:1;
1449 	unsigned int		needs_test:1;
1450 	int			len;
1451 };
1452 
1453 struct prog_entry;
1454 
1455 struct event_filter {
1456 	struct prog_entry __rcu	*prog;
1457 	char			*filter_string;
1458 };
1459 
1460 struct event_subsystem {
1461 	struct list_head	list;
1462 	const char		*name;
1463 	struct event_filter	*filter;
1464 	int			ref_count;
1465 };
1466 
1467 struct trace_subsystem_dir {
1468 	struct list_head		list;
1469 	struct event_subsystem		*subsystem;
1470 	struct trace_array		*tr;
1471 	struct eventfs_inode		*ei;
1472 	int				ref_count;
1473 	int				nr_events;
1474 };
1475 
1476 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1477 				     struct trace_buffer *buffer,
1478 				     struct ring_buffer_event *event,
1479 				     unsigned int trcace_ctx,
1480 				     struct pt_regs *regs);
1481 
1482 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1483 					      struct trace_buffer *buffer,
1484 					      struct ring_buffer_event *event,
1485 					      unsigned int trace_ctx)
1486 {
1487 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1488 }
1489 
1490 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1491 int trace_save_cmdline(struct task_struct *tsk);
1492 int trace_create_savedcmd(void);
1493 int trace_alloc_tgid_map(void);
1494 void trace_free_saved_cmdlines_buffer(void);
1495 
1496 extern const struct file_operations tracing_saved_cmdlines_fops;
1497 extern const struct file_operations tracing_saved_tgids_fops;
1498 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1499 
1500 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1501 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1502 void trace_buffered_event_disable(void);
1503 void trace_buffered_event_enable(void);
1504 
1505 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1506 
1507 static inline void
1508 __trace_event_discard_commit(struct trace_buffer *buffer,
1509 			     struct ring_buffer_event *event)
1510 {
1511 	if (this_cpu_read(trace_buffered_event) == event) {
1512 		/* Simply release the temp buffer and enable preemption */
1513 		this_cpu_dec(trace_buffered_event_cnt);
1514 		preempt_enable_notrace();
1515 		return;
1516 	}
1517 	/* ring_buffer_discard_commit() enables preemption */
1518 	ring_buffer_discard_commit(buffer, event);
1519 }
1520 
1521 /*
1522  * Helper function for event_trigger_unlock_commit{_regs}().
1523  * If there are event triggers attached to this event that requires
1524  * filtering against its fields, then they will be called as the
1525  * entry already holds the field information of the current event.
1526  *
1527  * It also checks if the event should be discarded or not.
1528  * It is to be discarded if the event is soft disabled and the
1529  * event was only recorded to process triggers, or if the event
1530  * filter is active and this event did not match the filters.
1531  *
1532  * Returns true if the event is discarded, false otherwise.
1533  */
1534 static inline bool
1535 __event_trigger_test_discard(struct trace_event_file *file,
1536 			     struct trace_buffer *buffer,
1537 			     struct ring_buffer_event *event,
1538 			     void *entry,
1539 			     enum event_trigger_type *tt)
1540 {
1541 	unsigned long eflags = file->flags;
1542 
1543 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1544 		*tt = event_triggers_call(file, buffer, entry, event);
1545 
1546 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1547 				    EVENT_FILE_FL_FILTERED |
1548 				    EVENT_FILE_FL_PID_FILTER))))
1549 		return false;
1550 
1551 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1552 		goto discard;
1553 
1554 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1555 	    !filter_match_preds(file->filter, entry))
1556 		goto discard;
1557 
1558 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1559 	    trace_event_ignore_this_pid(file))
1560 		goto discard;
1561 
1562 	return false;
1563  discard:
1564 	__trace_event_discard_commit(buffer, event);
1565 	return true;
1566 }
1567 
1568 /**
1569  * event_trigger_unlock_commit - handle triggers and finish event commit
1570  * @file: The file pointer associated with the event
1571  * @buffer: The ring buffer that the event is being written to
1572  * @event: The event meta data in the ring buffer
1573  * @entry: The event itself
1574  * @trace_ctx: The tracing context flags.
1575  *
1576  * This is a helper function to handle triggers that require data
1577  * from the event itself. It also tests the event against filters and
1578  * if the event is soft disabled and should be discarded.
1579  */
1580 static inline void
1581 event_trigger_unlock_commit(struct trace_event_file *file,
1582 			    struct trace_buffer *buffer,
1583 			    struct ring_buffer_event *event,
1584 			    void *entry, unsigned int trace_ctx)
1585 {
1586 	enum event_trigger_type tt = ETT_NONE;
1587 
1588 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1589 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1590 
1591 	if (tt)
1592 		event_triggers_post_call(file, tt);
1593 }
1594 
1595 #define FILTER_PRED_INVALID	((unsigned short)-1)
1596 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1597 #define FILTER_PRED_FOLD	(1 << 15)
1598 
1599 /*
1600  * The max preds is the size of unsigned short with
1601  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1602  * and FOLD flags. The other is reserved.
1603  *
1604  * 2^14 preds is way more than enough.
1605  */
1606 #define MAX_FILTER_PRED		16384
1607 
1608 struct filter_pred;
1609 struct regex;
1610 
1611 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1612 
1613 enum regex_type {
1614 	MATCH_FULL = 0,
1615 	MATCH_FRONT_ONLY,
1616 	MATCH_MIDDLE_ONLY,
1617 	MATCH_END_ONLY,
1618 	MATCH_GLOB,
1619 	MATCH_INDEX,
1620 };
1621 
1622 struct regex {
1623 	char			pattern[MAX_FILTER_STR_VAL];
1624 	int			len;
1625 	int			field_len;
1626 	regex_match_func	match;
1627 };
1628 
1629 static inline bool is_string_field(struct ftrace_event_field *field)
1630 {
1631 	return field->filter_type == FILTER_DYN_STRING ||
1632 	       field->filter_type == FILTER_RDYN_STRING ||
1633 	       field->filter_type == FILTER_STATIC_STRING ||
1634 	       field->filter_type == FILTER_PTR_STRING ||
1635 	       field->filter_type == FILTER_COMM;
1636 }
1637 
1638 static inline bool is_function_field(struct ftrace_event_field *field)
1639 {
1640 	return field->filter_type == FILTER_TRACE_FN;
1641 }
1642 
1643 extern enum regex_type
1644 filter_parse_regex(char *buff, int len, char **search, int *not);
1645 extern void print_event_filter(struct trace_event_file *file,
1646 			       struct trace_seq *s);
1647 extern int apply_event_filter(struct trace_event_file *file,
1648 			      char *filter_string);
1649 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1650 					char *filter_string);
1651 extern void print_subsystem_event_filter(struct event_subsystem *system,
1652 					 struct trace_seq *s);
1653 extern int filter_assign_type(const char *type);
1654 extern int create_event_filter(struct trace_array *tr,
1655 			       struct trace_event_call *call,
1656 			       char *filter_str, bool set_str,
1657 			       struct event_filter **filterp);
1658 extern void free_event_filter(struct event_filter *filter);
1659 
1660 struct ftrace_event_field *
1661 trace_find_event_field(struct trace_event_call *call, char *name);
1662 
1663 extern void trace_event_enable_cmd_record(bool enable);
1664 extern void trace_event_enable_tgid_record(bool enable);
1665 
1666 extern int event_trace_init(void);
1667 extern int init_events(void);
1668 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1669 extern int event_trace_del_tracer(struct trace_array *tr);
1670 extern void __trace_early_add_events(struct trace_array *tr);
1671 
1672 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1673 						  const char *system,
1674 						  const char *event);
1675 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1676 						const char *system,
1677 						const char *event);
1678 
1679 static inline void *event_file_data(struct file *filp)
1680 {
1681 	return READ_ONCE(file_inode(filp)->i_private);
1682 }
1683 
1684 extern struct mutex event_mutex;
1685 extern struct list_head ftrace_events;
1686 
1687 /*
1688  * When the trace_event_file is the filp->i_private pointer,
1689  * it must be taken under the event_mutex lock, and then checked
1690  * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1691  * data pointed to by the trace_event_file can not be trusted.
1692  *
1693  * Use the event_file_file() to access the trace_event_file from
1694  * the filp the first time under the event_mutex and check for
1695  * NULL. If it is needed to be retrieved again and the event_mutex
1696  * is still held, then the event_file_data() can be used and it
1697  * is guaranteed to be valid.
1698  */
1699 static inline struct trace_event_file *event_file_file(struct file *filp)
1700 {
1701 	struct trace_event_file *file;
1702 
1703 	lockdep_assert_held(&event_mutex);
1704 	file = READ_ONCE(file_inode(filp)->i_private);
1705 	if (!file || file->flags & EVENT_FILE_FL_FREED)
1706 		return NULL;
1707 	return file;
1708 }
1709 
1710 extern const struct file_operations event_trigger_fops;
1711 extern const struct file_operations event_hist_fops;
1712 extern const struct file_operations event_hist_debug_fops;
1713 extern const struct file_operations event_inject_fops;
1714 
1715 #ifdef CONFIG_HIST_TRIGGERS
1716 extern int register_trigger_hist_cmd(void);
1717 extern int register_trigger_hist_enable_disable_cmds(void);
1718 #else
1719 static inline int register_trigger_hist_cmd(void) { return 0; }
1720 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1721 #endif
1722 
1723 extern int register_trigger_cmds(void);
1724 extern void clear_event_triggers(struct trace_array *tr);
1725 
1726 enum {
1727 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1728 };
1729 
1730 struct event_trigger_data {
1731 	unsigned long			count;
1732 	int				ref;
1733 	int				flags;
1734 	const struct event_trigger_ops	*ops;
1735 	struct event_command		*cmd_ops;
1736 	struct event_filter __rcu	*filter;
1737 	char				*filter_str;
1738 	void				*private_data;
1739 	bool				paused;
1740 	bool				paused_tmp;
1741 	struct list_head		list;
1742 	char				*name;
1743 	struct list_head		named_list;
1744 	struct event_trigger_data	*named_data;
1745 };
1746 
1747 /* Avoid typos */
1748 #define ENABLE_EVENT_STR	"enable_event"
1749 #define DISABLE_EVENT_STR	"disable_event"
1750 #define ENABLE_HIST_STR		"enable_hist"
1751 #define DISABLE_HIST_STR	"disable_hist"
1752 
1753 struct enable_trigger_data {
1754 	struct trace_event_file		*file;
1755 	bool				enable;
1756 	bool				hist;
1757 };
1758 
1759 extern int event_enable_trigger_print(struct seq_file *m,
1760 				      struct event_trigger_data *data);
1761 extern void event_enable_trigger_free(struct event_trigger_data *data);
1762 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1763 				      struct trace_event_file *file,
1764 				      char *glob, char *cmd,
1765 				      char *param_and_filter);
1766 extern int event_enable_register_trigger(char *glob,
1767 					 struct event_trigger_data *data,
1768 					 struct trace_event_file *file);
1769 extern void event_enable_unregister_trigger(char *glob,
1770 					    struct event_trigger_data *test,
1771 					    struct trace_event_file *file);
1772 extern void trigger_data_free(struct event_trigger_data *data);
1773 extern int event_trigger_init(struct event_trigger_data *data);
1774 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1775 					      int trigger_enable);
1776 extern void update_cond_flag(struct trace_event_file *file);
1777 extern int set_trigger_filter(char *filter_str,
1778 			      struct event_trigger_data *trigger_data,
1779 			      struct trace_event_file *file);
1780 extern struct event_trigger_data *find_named_trigger(const char *name);
1781 extern bool is_named_trigger(struct event_trigger_data *test);
1782 extern int save_named_trigger(const char *name,
1783 			      struct event_trigger_data *data);
1784 extern void del_named_trigger(struct event_trigger_data *data);
1785 extern void pause_named_trigger(struct event_trigger_data *data);
1786 extern void unpause_named_trigger(struct event_trigger_data *data);
1787 extern void set_named_trigger_data(struct event_trigger_data *data,
1788 				   struct event_trigger_data *named_data);
1789 extern struct event_trigger_data *
1790 get_named_trigger_data(struct event_trigger_data *data);
1791 extern int register_event_command(struct event_command *cmd);
1792 extern int unregister_event_command(struct event_command *cmd);
1793 extern int register_trigger_hist_enable_disable_cmds(void);
1794 extern bool event_trigger_check_remove(const char *glob);
1795 extern bool event_trigger_empty_param(const char *param);
1796 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1797 					 char **filter, bool param_required);
1798 extern struct event_trigger_data *
1799 event_trigger_alloc(struct event_command *cmd_ops,
1800 		    char *cmd,
1801 		    char *param,
1802 		    void *private_data);
1803 extern int event_trigger_parse_num(char *trigger,
1804 				   struct event_trigger_data *trigger_data);
1805 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1806 				    struct trace_event_file *file,
1807 				    char *param,
1808 				    struct event_trigger_data *trigger_data);
1809 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1810 				       struct event_trigger_data *trigger_data);
1811 extern int event_trigger_register(struct event_command *cmd_ops,
1812 				  struct trace_event_file *file,
1813 				  char *glob,
1814 				  struct event_trigger_data *trigger_data);
1815 extern void event_trigger_unregister(struct event_command *cmd_ops,
1816 				     struct trace_event_file *file,
1817 				     char *glob,
1818 				     struct event_trigger_data *trigger_data);
1819 
1820 extern void event_file_get(struct trace_event_file *file);
1821 extern void event_file_put(struct trace_event_file *file);
1822 
1823 /**
1824  * struct event_trigger_ops - callbacks for trace event triggers
1825  *
1826  * The methods in this structure provide per-event trigger hooks for
1827  * various trigger operations.
1828  *
1829  * The @init and @free methods are used during trigger setup and
1830  * teardown, typically called from an event_command's @parse()
1831  * function implementation.
1832  *
1833  * The @print method is used to print the trigger spec.
1834  *
1835  * The @trigger method is the function that actually implements the
1836  * trigger and is called in the context of the triggering event
1837  * whenever that event occurs.
1838  *
1839  * All the methods below, except for @init() and @free(), must be
1840  * implemented.
1841  *
1842  * @trigger: The trigger 'probe' function called when the triggering
1843  *	event occurs.  The data passed into this callback is the data
1844  *	that was supplied to the event_command @reg() function that
1845  *	registered the trigger (see struct event_command) along with
1846  *	the trace record, rec.
1847  *
1848  * @init: An optional initialization function called for the trigger
1849  *	when the trigger is registered (via the event_command reg()
1850  *	function).  This can be used to perform per-trigger
1851  *	initialization such as incrementing a per-trigger reference
1852  *	count, for instance.  This is usually implemented by the
1853  *	generic utility function @event_trigger_init() (see
1854  *	trace_event_triggers.c).
1855  *
1856  * @free: An optional de-initialization function called for the
1857  *	trigger when the trigger is unregistered (via the
1858  *	event_command @reg() function).  This can be used to perform
1859  *	per-trigger de-initialization such as decrementing a
1860  *	per-trigger reference count and freeing corresponding trigger
1861  *	data, for instance.  This is usually implemented by the
1862  *	generic utility function @event_trigger_free() (see
1863  *	trace_event_triggers.c).
1864  *
1865  * @print: The callback function invoked to have the trigger print
1866  *	itself.  This is usually implemented by a wrapper function
1867  *	that calls the generic utility function @event_trigger_print()
1868  *	(see trace_event_triggers.c).
1869  */
1870 struct event_trigger_ops {
1871 	void			(*trigger)(struct event_trigger_data *data,
1872 					   struct trace_buffer *buffer,
1873 					   void *rec,
1874 					   struct ring_buffer_event *rbe);
1875 	int			(*init)(struct event_trigger_data *data);
1876 	void			(*free)(struct event_trigger_data *data);
1877 	int			(*print)(struct seq_file *m,
1878 					 struct event_trigger_data *data);
1879 };
1880 
1881 /**
1882  * struct event_command - callbacks and data members for event commands
1883  *
1884  * Event commands are invoked by users by writing the command name
1885  * into the 'trigger' file associated with a trace event.  The
1886  * parameters associated with a specific invocation of an event
1887  * command are used to create an event trigger instance, which is
1888  * added to the list of trigger instances associated with that trace
1889  * event.  When the event is hit, the set of triggers associated with
1890  * that event is invoked.
1891  *
1892  * The data members in this structure provide per-event command data
1893  * for various event commands.
1894  *
1895  * All the data members below, except for @post_trigger, must be set
1896  * for each event command.
1897  *
1898  * @name: The unique name that identifies the event command.  This is
1899  *	the name used when setting triggers via trigger files.
1900  *
1901  * @trigger_type: A unique id that identifies the event command
1902  *	'type'.  This value has two purposes, the first to ensure that
1903  *	only one trigger of the same type can be set at a given time
1904  *	for a particular event e.g. it doesn't make sense to have both
1905  *	a traceon and traceoff trigger attached to a single event at
1906  *	the same time, so traceon and traceoff have the same type
1907  *	though they have different names.  The @trigger_type value is
1908  *	also used as a bit value for deferring the actual trigger
1909  *	action until after the current event is finished.  Some
1910  *	commands need to do this if they themselves log to the trace
1911  *	buffer (see the @post_trigger() member below).  @trigger_type
1912  *	values are defined by adding new values to the trigger_type
1913  *	enum in include/linux/trace_events.h.
1914  *
1915  * @flags: See the enum event_command_flags below.
1916  *
1917  * All the methods below, except for @set_filter() and @unreg_all(),
1918  * must be implemented.
1919  *
1920  * @parse: The callback function responsible for parsing and
1921  *	registering the trigger written to the 'trigger' file by the
1922  *	user.  It allocates the trigger instance and registers it with
1923  *	the appropriate trace event.  It makes use of the other
1924  *	event_command callback functions to orchestrate this, and is
1925  *	usually implemented by the generic utility function
1926  *	@event_trigger_callback() (see trace_event_triggers.c).
1927  *
1928  * @reg: Adds the trigger to the list of triggers associated with the
1929  *	event, and enables the event trigger itself, after
1930  *	initializing it (via the event_trigger_ops @init() function).
1931  *	This is also where commands can use the @trigger_type value to
1932  *	make the decision as to whether or not multiple instances of
1933  *	the trigger should be allowed.  This is usually implemented by
1934  *	the generic utility function @register_trigger() (see
1935  *	trace_event_triggers.c).
1936  *
1937  * @unreg: Removes the trigger from the list of triggers associated
1938  *	with the event, and disables the event trigger itself, after
1939  *	initializing it (via the event_trigger_ops @free() function).
1940  *	This is usually implemented by the generic utility function
1941  *	@unregister_trigger() (see trace_event_triggers.c).
1942  *
1943  * @unreg_all: An optional function called to remove all the triggers
1944  *	from the list of triggers associated with the event.  Called
1945  *	when a trigger file is opened in truncate mode.
1946  *
1947  * @set_filter: An optional function called to parse and set a filter
1948  *	for the trigger.  If no @set_filter() method is set for the
1949  *	event command, filters set by the user for the command will be
1950  *	ignored.  This is usually implemented by the generic utility
1951  *	function @set_trigger_filter() (see trace_event_triggers.c).
1952  *
1953  * @get_trigger_ops: The callback function invoked to retrieve the
1954  *	event_trigger_ops implementation associated with the command.
1955  *	This callback function allows a single event_command to
1956  *	support multiple trigger implementations via different sets of
1957  *	event_trigger_ops, depending on the value of the @param
1958  *	string.
1959  */
1960 struct event_command {
1961 	struct list_head	list;
1962 	char			*name;
1963 	enum event_trigger_type	trigger_type;
1964 	int			flags;
1965 	int			(*parse)(struct event_command *cmd_ops,
1966 					 struct trace_event_file *file,
1967 					 char *glob, char *cmd,
1968 					 char *param_and_filter);
1969 	int			(*reg)(char *glob,
1970 				       struct event_trigger_data *data,
1971 				       struct trace_event_file *file);
1972 	void			(*unreg)(char *glob,
1973 					 struct event_trigger_data *data,
1974 					 struct trace_event_file *file);
1975 	void			(*unreg_all)(struct trace_event_file *file);
1976 	int			(*set_filter)(char *filter_str,
1977 					      struct event_trigger_data *data,
1978 					      struct trace_event_file *file);
1979 	const struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1980 };
1981 
1982 /**
1983  * enum event_command_flags - flags for struct event_command
1984  *
1985  * @POST_TRIGGER: A flag that says whether or not this command needs
1986  *	to have its action delayed until after the current event has
1987  *	been closed.  Some triggers need to avoid being invoked while
1988  *	an event is currently in the process of being logged, since
1989  *	the trigger may itself log data into the trace buffer.  Thus
1990  *	we make sure the current event is committed before invoking
1991  *	those triggers.  To do that, the trigger invocation is split
1992  *	in two - the first part checks the filter using the current
1993  *	trace record; if a command has the @post_trigger flag set, it
1994  *	sets a bit for itself in the return value, otherwise it
1995  *	directly invokes the trigger.  Once all commands have been
1996  *	either invoked or set their return flag, the current record is
1997  *	either committed or discarded.  At that point, if any commands
1998  *	have deferred their triggers, those commands are finally
1999  *	invoked following the close of the current event.  In other
2000  *	words, if the event_trigger_ops @func() probe implementation
2001  *	itself logs to the trace buffer, this flag should be set,
2002  *	otherwise it can be left unspecified.
2003  *
2004  * @NEEDS_REC: A flag that says whether or not this command needs
2005  *	access to the trace record in order to perform its function,
2006  *	regardless of whether or not it has a filter associated with
2007  *	it (filters make a trigger require access to the trace record
2008  *	but are not always present).
2009  */
2010 enum event_command_flags {
2011 	EVENT_CMD_FL_POST_TRIGGER	= 1,
2012 	EVENT_CMD_FL_NEEDS_REC		= 2,
2013 };
2014 
2015 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
2016 {
2017 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
2018 }
2019 
2020 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
2021 {
2022 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
2023 }
2024 
2025 extern int trace_event_enable_disable(struct trace_event_file *file,
2026 				      int enable, int soft_disable);
2027 extern int tracing_alloc_snapshot(void);
2028 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
2029 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
2030 
2031 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
2032 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2033 
2034 extern const char *__start___trace_bprintk_fmt[];
2035 extern const char *__stop___trace_bprintk_fmt[];
2036 
2037 extern const char *__start___tracepoint_str[];
2038 extern const char *__stop___tracepoint_str[];
2039 
2040 void trace_printk_control(bool enabled);
2041 void trace_printk_start_comm(void);
2042 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2043 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2044 
2045 /* Used from boot time tracer */
2046 extern int trace_set_options(struct trace_array *tr, char *option);
2047 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2048 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2049 					  unsigned long size, int cpu_id);
2050 extern int tracing_set_cpumask(struct trace_array *tr,
2051 				cpumask_var_t tracing_cpumask_new);
2052 
2053 
2054 #define MAX_EVENT_NAME_LEN	64
2055 
2056 extern ssize_t trace_parse_run_command(struct file *file,
2057 		const char __user *buffer, size_t count, loff_t *ppos,
2058 		int (*createfn)(const char *));
2059 
2060 extern unsigned int err_pos(char *cmd, const char *str);
2061 extern void tracing_log_err(struct trace_array *tr,
2062 			    const char *loc, const char *cmd,
2063 			    const char **errs, u8 type, u16 pos);
2064 
2065 /*
2066  * Normal trace_printk() and friends allocates special buffers
2067  * to do the manipulation, as well as saves the print formats
2068  * into sections to display. But the trace infrastructure wants
2069  * to use these without the added overhead at the price of being
2070  * a bit slower (used mainly for warnings, where we don't care
2071  * about performance). The internal_trace_puts() is for such
2072  * a purpose.
2073  */
2074 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2075 
2076 #undef FTRACE_ENTRY
2077 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2078 	extern struct trace_event_call					\
2079 	__aligned(4) event_##call;
2080 #undef FTRACE_ENTRY_DUP
2081 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2082 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2083 #undef FTRACE_ENTRY_PACKED
2084 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2085 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2086 
2087 #include "trace_entries.h"
2088 
2089 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2090 int perf_ftrace_event_register(struct trace_event_call *call,
2091 			       enum trace_reg type, void *data);
2092 #else
2093 #define perf_ftrace_event_register NULL
2094 #endif
2095 
2096 #ifdef CONFIG_FTRACE_SYSCALLS
2097 void init_ftrace_syscalls(void);
2098 const char *get_syscall_name(int syscall);
2099 #else
2100 static inline void init_ftrace_syscalls(void) { }
2101 static inline const char *get_syscall_name(int syscall)
2102 {
2103 	return NULL;
2104 }
2105 #endif
2106 
2107 #ifdef CONFIG_EVENT_TRACING
2108 void trace_event_init(void);
2109 void trace_event_eval_update(struct trace_eval_map **map, int len);
2110 /* Used from boot time tracer */
2111 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2112 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2113 #else
2114 static inline void __init trace_event_init(void) { }
2115 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2116 #endif
2117 
2118 #ifdef CONFIG_TRACER_SNAPSHOT
2119 void tracing_snapshot_instance(struct trace_array *tr);
2120 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2121 int tracing_arm_snapshot(struct trace_array *tr);
2122 void tracing_disarm_snapshot(struct trace_array *tr);
2123 #else
2124 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2125 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2126 {
2127 	return 0;
2128 }
2129 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
2130 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2131 #endif
2132 
2133 #ifdef CONFIG_PREEMPT_TRACER
2134 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2135 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2136 #else
2137 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2138 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2139 #endif
2140 #ifdef CONFIG_IRQSOFF_TRACER
2141 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2142 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2143 #else
2144 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2145 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2146 #endif
2147 
2148 /*
2149  * Reset the state of the trace_iterator so that it can read consumed data.
2150  * Normally, the trace_iterator is used for reading the data when it is not
2151  * consumed, and must retain state.
2152  */
2153 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2154 {
2155 	memset_startat(iter, 0, seq);
2156 	iter->pos = -1;
2157 }
2158 
2159 /* Check the name is good for event/group/fields */
2160 static inline bool __is_good_name(const char *name, bool hash_ok)
2161 {
2162 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2163 		return false;
2164 	while (*++name != '\0') {
2165 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2166 		    (!hash_ok || *name != '-'))
2167 			return false;
2168 	}
2169 	return true;
2170 }
2171 
2172 /* Check the name is good for event/group/fields */
2173 static inline bool is_good_name(const char *name)
2174 {
2175 	return __is_good_name(name, false);
2176 }
2177 
2178 /* Check the name is good for system */
2179 static inline bool is_good_system_name(const char *name)
2180 {
2181 	return __is_good_name(name, true);
2182 }
2183 
2184 /* Convert certain expected symbols into '_' when generating event names */
2185 static inline void sanitize_event_name(char *name)
2186 {
2187 	while (*name++ != '\0')
2188 		if (*name == ':' || *name == '.')
2189 			*name = '_';
2190 }
2191 
2192 /*
2193  * This is a generic way to read and write a u64 value from a file in tracefs.
2194  *
2195  * The value is stored on the variable pointed by *val. The value needs
2196  * to be at least *min and at most *max. The write is protected by an
2197  * existing *lock.
2198  */
2199 struct trace_min_max_param {
2200 	struct mutex	*lock;
2201 	u64		*val;
2202 	u64		*min;
2203 	u64		*max;
2204 };
2205 
2206 #define U64_STR_SIZE		24	/* 20 digits max */
2207 
2208 extern const struct file_operations trace_min_max_fops;
2209 
2210 #ifdef CONFIG_RV
2211 extern int rv_init_interface(void);
2212 #else
2213 static inline int rv_init_interface(void)
2214 {
2215 	return 0;
2216 }
2217 #endif
2218 
2219 /*
2220  * This is used only to distinguish
2221  * function address from trampoline code.
2222  * So this value has no meaning.
2223  */
2224 #define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2225 
2226 #endif /* _LINUX_KERNEL_TRACE_H */
2227