xref: /linux/kernel/trace/trace.h (revision c061cf420ded391e32f99cd483e1e0107f213b12)
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_GRAPH_RETADDR_ENT,
50 	TRACE_USER_STACK,
51 	TRACE_BLK,
52 	TRACE_BPUTS,
53 	TRACE_HWLAT,
54 	TRACE_OSNOISE,
55 	TRACE_TIMERLAT,
56 	TRACE_RAW_DATA,
57 	TRACE_FUNC_REPEATS,
58 
59 	__TRACE_LAST_TYPE,
60 };
61 
62 
63 #undef __field
64 #define __field(type, item)		type	item;
65 
66 #undef __field_fn
67 #define __field_fn(type, item)		type	item;
68 
69 #undef __field_struct
70 #define __field_struct(type, item)	__field(type, item)
71 
72 #undef __field_desc
73 #define __field_desc(type, container, item)
74 
75 #undef __field_packed
76 #define __field_packed(type, container, item)
77 
78 #undef __array
79 #define __array(type, item, size)	type	item[size];
80 
81 /*
82  * For backward compatibility, older user space expects to see the
83  * kernel_stack event with a fixed size caller field. But today the fix
84  * size is ignored by the kernel, and the real structure is dynamic.
85  * Expose to user space: "unsigned long caller[8];" but the real structure
86  * will be "unsigned long caller[] __counted_by(size)"
87  */
88 #undef __stack_array
89 #define __stack_array(type, item, size, field)		type item[] __counted_by(field);
90 
91 #undef __array_desc
92 #define __array_desc(type, container, item, size)
93 
94 #undef __dynamic_array
95 #define __dynamic_array(type, item)	type	item[];
96 
97 #undef __rel_dynamic_array
98 #define __rel_dynamic_array(type, item)	type	item[];
99 
100 #undef F_STRUCT
101 #define F_STRUCT(args...)		args
102 
103 #undef FTRACE_ENTRY
104 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
105 	struct struct_name {						\
106 		struct trace_entry	ent;				\
107 		tstruct							\
108 	}
109 
110 #undef FTRACE_ENTRY_DUP
111 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
112 
113 #undef FTRACE_ENTRY_REG
114 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
115 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
116 
117 #undef FTRACE_ENTRY_PACKED
118 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
119 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
120 
121 #include "trace_entries.h"
122 
123 /* Use this for memory failure errors */
124 #define MEM_FAIL(condition, fmt, ...)					\
125 	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
126 
127 #define FAULT_STRING "(fault)"
128 
129 #define HIST_STACKTRACE_DEPTH	16
130 #define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
131 #define HIST_STACKTRACE_SKIP	5
132 
133 /*
134  * syscalls are special, and need special handling, this is why
135  * they are not included in trace_entries.h
136  */
137 struct syscall_trace_enter {
138 	struct trace_entry	ent;
139 	int			nr;
140 	unsigned long		args[];
141 };
142 
143 struct syscall_trace_exit {
144 	struct trace_entry	ent;
145 	int			nr;
146 	long			ret;
147 };
148 
149 struct kprobe_trace_entry_head {
150 	struct trace_entry	ent;
151 	unsigned long		ip;
152 };
153 
154 struct eprobe_trace_entry_head {
155 	struct trace_entry	ent;
156 };
157 
158 struct kretprobe_trace_entry_head {
159 	struct trace_entry	ent;
160 	unsigned long		func;
161 	unsigned long		ret_ip;
162 };
163 
164 struct fentry_trace_entry_head {
165 	struct trace_entry	ent;
166 	unsigned long		ip;
167 };
168 
169 struct fexit_trace_entry_head {
170 	struct trace_entry	ent;
171 	unsigned long		func;
172 	unsigned long		ret_ip;
173 };
174 
175 #define TRACE_BUF_SIZE		1024
176 
177 struct trace_array;
178 
179 /*
180  * The CPU trace array - it consists of thousands of trace entries
181  * plus some other descriptor data: (for example which task started
182  * the trace, etc.)
183  */
184 struct trace_array_cpu {
185 	atomic_t		disabled;
186 	void			*buffer_page;	/* ring buffer spare */
187 
188 	unsigned long		entries;
189 	unsigned long		saved_latency;
190 	unsigned long		critical_start;
191 	unsigned long		critical_end;
192 	unsigned long		critical_sequence;
193 	unsigned long		nice;
194 	unsigned long		policy;
195 	unsigned long		rt_priority;
196 	unsigned long		skipped_entries;
197 	u64			preempt_timestamp;
198 	pid_t			pid;
199 	kuid_t			uid;
200 	char			comm[TASK_COMM_LEN];
201 
202 #ifdef CONFIG_FUNCTION_TRACER
203 	int			ftrace_ignore_pid;
204 #endif
205 	bool			ignore_pid;
206 };
207 
208 struct tracer;
209 struct trace_option_dentry;
210 
211 struct array_buffer {
212 	struct trace_array		*tr;
213 	struct trace_buffer		*buffer;
214 	struct trace_array_cpu __percpu	*data;
215 	u64				time_start;
216 	int				cpu;
217 };
218 
219 #define TRACE_FLAGS_MAX_SIZE		32
220 
221 struct trace_options {
222 	struct tracer			*tracer;
223 	struct trace_option_dentry	*topts;
224 };
225 
226 struct trace_pid_list *trace_pid_list_alloc(void);
227 void trace_pid_list_free(struct trace_pid_list *pid_list);
228 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
229 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
231 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
232 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
233 			unsigned int *next);
234 
235 enum {
236 	TRACE_PIDS		= BIT(0),
237 	TRACE_NO_PIDS		= BIT(1),
238 };
239 
pid_type_enabled(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)240 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
241 				    struct trace_pid_list *no_pid_list)
242 {
243 	/* Return true if the pid list in type has pids */
244 	return ((type & TRACE_PIDS) && pid_list) ||
245 		((type & TRACE_NO_PIDS) && no_pid_list);
246 }
247 
still_need_pid_events(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)248 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
249 					 struct trace_pid_list *no_pid_list)
250 {
251 	/*
252 	 * Turning off what is in @type, return true if the "other"
253 	 * pid list, still has pids in it.
254 	 */
255 	return (!(type & TRACE_PIDS) && pid_list) ||
256 		(!(type & TRACE_NO_PIDS) && no_pid_list);
257 }
258 
259 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
260 
261 /**
262  * struct cond_snapshot - conditional snapshot data and callback
263  *
264  * The cond_snapshot structure encapsulates a callback function and
265  * data associated with the snapshot for a given tracing instance.
266  *
267  * When a snapshot is taken conditionally, by invoking
268  * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
269  * passed in turn to the cond_snapshot.update() function.  That data
270  * can be compared by the update() implementation with the cond_data
271  * contained within the struct cond_snapshot instance associated with
272  * the trace_array.  Because the tr->max_lock is held throughout the
273  * update() call, the update() function can directly retrieve the
274  * cond_snapshot and cond_data associated with the per-instance
275  * snapshot associated with the trace_array.
276  *
277  * The cond_snapshot.update() implementation can save data to be
278  * associated with the snapshot if it decides to, and returns 'true'
279  * in that case, or it returns 'false' if the conditional snapshot
280  * shouldn't be taken.
281  *
282  * The cond_snapshot instance is created and associated with the
283  * user-defined cond_data by tracing_cond_snapshot_enable().
284  * Likewise, the cond_snapshot instance is destroyed and is no longer
285  * associated with the trace instance by
286  * tracing_cond_snapshot_disable().
287  *
288  * The method below is required.
289  *
290  * @update: When a conditional snapshot is invoked, the update()
291  *	callback function is invoked with the tr->max_lock held.  The
292  *	update() implementation signals whether or not to actually
293  *	take the snapshot, by returning 'true' if so, 'false' if no
294  *	snapshot should be taken.  Because the max_lock is held for
295  *	the duration of update(), the implementation is safe to
296  *	directly retrieved and save any implementation data it needs
297  *	to in association with the snapshot.
298  */
299 struct cond_snapshot {
300 	void				*cond_data;
301 	cond_update_fn_t		update;
302 };
303 
304 /*
305  * struct trace_func_repeats - used to keep track of the consecutive
306  * (on the same CPU) calls of a single function.
307  */
308 struct trace_func_repeats {
309 	unsigned long	ip;
310 	unsigned long	parent_ip;
311 	unsigned long	count;
312 	u64		ts_last_call;
313 };
314 
315 /*
316  * The trace array - an array of per-CPU trace arrays. This is the
317  * highest level data structure that individual tracers deal with.
318  * They have on/off state as well:
319  */
320 struct trace_array {
321 	struct list_head	list;
322 	char			*name;
323 	struct array_buffer	array_buffer;
324 #ifdef CONFIG_TRACER_MAX_TRACE
325 	/*
326 	 * The max_buffer is used to snapshot the trace when a maximum
327 	 * latency is reached, or when the user initiates a snapshot.
328 	 * Some tracers will use this to store a maximum trace while
329 	 * it continues examining live traces.
330 	 *
331 	 * The buffers for the max_buffer are set up the same as the array_buffer
332 	 * When a snapshot is taken, the buffer of the max_buffer is swapped
333 	 * with the buffer of the array_buffer and the buffers are reset for
334 	 * the array_buffer so the tracing can continue.
335 	 */
336 	struct array_buffer	max_buffer;
337 	bool			allocated_snapshot;
338 	spinlock_t		snapshot_trigger_lock;
339 	unsigned int		snapshot;
340 	unsigned long		max_latency;
341 #ifdef CONFIG_FSNOTIFY
342 	struct dentry		*d_max_latency;
343 	struct work_struct	fsnotify_work;
344 	struct irq_work		fsnotify_irqwork;
345 #endif
346 #endif
347 	/* The below is for memory mapped ring buffer */
348 	unsigned int		mapped;
349 	unsigned long		range_addr_start;
350 	unsigned long		range_addr_size;
351 	long			text_delta;
352 	long			data_delta;
353 
354 	struct trace_pid_list	__rcu *filtered_pids;
355 	struct trace_pid_list	__rcu *filtered_no_pids;
356 	/*
357 	 * max_lock is used to protect the swapping of buffers
358 	 * when taking a max snapshot. The buffers themselves are
359 	 * protected by per_cpu spinlocks. But the action of the swap
360 	 * needs its own lock.
361 	 *
362 	 * This is defined as a arch_spinlock_t in order to help
363 	 * with performance when lockdep debugging is enabled.
364 	 *
365 	 * It is also used in other places outside the update_max_tr
366 	 * so it needs to be defined outside of the
367 	 * CONFIG_TRACER_MAX_TRACE.
368 	 */
369 	arch_spinlock_t		max_lock;
370 	int			buffer_disabled;
371 #ifdef CONFIG_FTRACE_SYSCALLS
372 	int			sys_refcount_enter;
373 	int			sys_refcount_exit;
374 	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
375 	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
376 #endif
377 	int			stop_count;
378 	int			clock_id;
379 	int			nr_topts;
380 	bool			clear_trace;
381 	int			buffer_percent;
382 	unsigned int		n_err_log_entries;
383 	struct tracer		*current_trace;
384 	unsigned int		trace_flags;
385 	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
386 	unsigned int		flags;
387 	raw_spinlock_t		start_lock;
388 	const char		*system_names;
389 	struct list_head	err_log;
390 	struct dentry		*dir;
391 	struct dentry		*options;
392 	struct dentry		*percpu_dir;
393 	struct eventfs_inode	*event_dir;
394 	struct trace_options	*topts;
395 	struct list_head	systems;
396 	struct list_head	events;
397 	struct trace_event_file *trace_marker_file;
398 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
399 	/* one per_cpu trace_pipe can be opened by only one user */
400 	cpumask_var_t		pipe_cpumask;
401 	int			ref;
402 	int			trace_ref;
403 #ifdef CONFIG_FUNCTION_TRACER
404 	struct ftrace_ops	*ops;
405 	struct trace_pid_list	__rcu *function_pids;
406 	struct trace_pid_list	__rcu *function_no_pids;
407 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
408 	struct fgraph_ops	*gops;
409 #endif
410 #ifdef CONFIG_DYNAMIC_FTRACE
411 	/* All of these are protected by the ftrace_lock */
412 	struct list_head	func_probes;
413 	struct list_head	mod_trace;
414 	struct list_head	mod_notrace;
415 #endif
416 	/* function tracing enabled */
417 	int			function_enabled;
418 #endif
419 	int			no_filter_buffering_ref;
420 	struct list_head	hist_vars;
421 #ifdef CONFIG_TRACER_SNAPSHOT
422 	struct cond_snapshot	*cond_snapshot;
423 #endif
424 	struct trace_func_repeats	__percpu *last_func_repeats;
425 	/*
426 	 * On boot up, the ring buffer is set to the minimum size, so that
427 	 * we do not waste memory on systems that are not using tracing.
428 	 */
429 	bool ring_buffer_expanded;
430 };
431 
432 enum {
433 	TRACE_ARRAY_FL_GLOBAL	= BIT(0),
434 	TRACE_ARRAY_FL_BOOT	= BIT(1),
435 };
436 
437 extern struct list_head ftrace_trace_arrays;
438 
439 extern struct mutex trace_types_lock;
440 
441 extern int trace_array_get(struct trace_array *tr);
442 extern int tracing_check_open_get_tr(struct trace_array *tr);
443 extern struct trace_array *trace_array_find(const char *instance);
444 extern struct trace_array *trace_array_find_get(const char *instance);
445 
446 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
447 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
448 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
449 
450 extern bool trace_clock_in_ns(struct trace_array *tr);
451 
452 /*
453  * The global tracer (top) should be the first trace array added,
454  * but we check the flag anyway.
455  */
top_trace_array(void)456 static inline struct trace_array *top_trace_array(void)
457 {
458 	struct trace_array *tr;
459 
460 	if (list_empty(&ftrace_trace_arrays))
461 		return NULL;
462 
463 	tr = list_entry(ftrace_trace_arrays.prev,
464 			typeof(*tr), list);
465 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
466 	return tr;
467 }
468 
469 #define FTRACE_CMP_TYPE(var, type) \
470 	__builtin_types_compatible_p(typeof(var), type *)
471 
472 #undef IF_ASSIGN
473 #define IF_ASSIGN(var, entry, etype, id)			\
474 	if (FTRACE_CMP_TYPE(var, etype)) {			\
475 		var = (typeof(var))(entry);			\
476 		WARN_ON(id != 0 && (entry)->type != id);	\
477 		break;						\
478 	}
479 
480 /* Will cause compile errors if type is not found. */
481 extern void __ftrace_bad_type(void);
482 
483 /*
484  * The trace_assign_type is a verifier that the entry type is
485  * the same as the type being assigned. To add new types simply
486  * add a line with the following format:
487  *
488  * IF_ASSIGN(var, ent, type, id);
489  *
490  *  Where "type" is the trace type that includes the trace_entry
491  *  as the "ent" item. And "id" is the trace identifier that is
492  *  used in the trace_type enum.
493  *
494  *  If the type can have more than one id, then use zero.
495  */
496 #define trace_assign_type(var, ent)					\
497 	do {								\
498 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
499 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
500 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
501 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
502 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
503 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
504 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
505 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
506 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
507 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
508 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
509 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
510 			  TRACE_MMIO_RW);				\
511 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
512 			  TRACE_MMIO_MAP);				\
513 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
514 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
515 			  TRACE_GRAPH_ENT);		\
516 		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
517 			  TRACE_GRAPH_RETADDR_ENT);		\
518 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
519 			  TRACE_GRAPH_RET);		\
520 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
521 			  TRACE_FUNC_REPEATS);				\
522 		__ftrace_bad_type();					\
523 	} while (0)
524 
525 /*
526  * An option specific to a tracer. This is a boolean value.
527  * The bit is the bit index that sets its value on the
528  * flags value in struct tracer_flags.
529  */
530 struct tracer_opt {
531 	const char	*name; /* Will appear on the trace_options file */
532 	u32		bit; /* Mask assigned in val field in tracer_flags */
533 };
534 
535 /*
536  * The set of specific options for a tracer. Your tracer
537  * have to set the initial value of the flags val.
538  */
539 struct tracer_flags {
540 	u32			val;
541 	struct tracer_opt	*opts;
542 	struct tracer		*trace;
543 };
544 
545 /* Makes more easy to define a tracer opt */
546 #define TRACER_OPT(s, b)	.name = #s, .bit = b
547 
548 
549 struct trace_option_dentry {
550 	struct tracer_opt		*opt;
551 	struct tracer_flags		*flags;
552 	struct trace_array		*tr;
553 	struct dentry			*entry;
554 };
555 
556 /**
557  * struct tracer - a specific tracer and its callbacks to interact with tracefs
558  * @name: the name chosen to select it on the available_tracers file
559  * @init: called when one switches to this tracer (echo name > current_tracer)
560  * @reset: called when one switches to another tracer
561  * @start: called when tracing is unpaused (echo 1 > tracing_on)
562  * @stop: called when tracing is paused (echo 0 > tracing_on)
563  * @update_thresh: called when tracing_thresh is updated
564  * @open: called when the trace file is opened
565  * @pipe_open: called when the trace_pipe file is opened
566  * @close: called when the trace file is released
567  * @pipe_close: called when the trace_pipe file is released
568  * @read: override the default read callback on trace_pipe
569  * @splice_read: override the default splice_read callback on trace_pipe
570  * @selftest: selftest to run on boot (see trace_selftest.c)
571  * @print_headers: override the first lines that describe your columns
572  * @print_line: callback that prints a trace
573  * @set_flag: signals one of your private flags changed (trace_options file)
574  * @flags: your private flags
575  */
576 struct tracer {
577 	const char		*name;
578 	int			(*init)(struct trace_array *tr);
579 	void			(*reset)(struct trace_array *tr);
580 	void			(*start)(struct trace_array *tr);
581 	void			(*stop)(struct trace_array *tr);
582 	int			(*update_thresh)(struct trace_array *tr);
583 	void			(*open)(struct trace_iterator *iter);
584 	void			(*pipe_open)(struct trace_iterator *iter);
585 	void			(*close)(struct trace_iterator *iter);
586 	void			(*pipe_close)(struct trace_iterator *iter);
587 	ssize_t			(*read)(struct trace_iterator *iter,
588 					struct file *filp, char __user *ubuf,
589 					size_t cnt, loff_t *ppos);
590 	ssize_t			(*splice_read)(struct trace_iterator *iter,
591 					       struct file *filp,
592 					       loff_t *ppos,
593 					       struct pipe_inode_info *pipe,
594 					       size_t len,
595 					       unsigned int flags);
596 #ifdef CONFIG_FTRACE_STARTUP_TEST
597 	int			(*selftest)(struct tracer *trace,
598 					    struct trace_array *tr);
599 #endif
600 	void			(*print_header)(struct seq_file *m);
601 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
602 	/* If you handled the flag setting, return 0 */
603 	int			(*set_flag)(struct trace_array *tr,
604 					    u32 old_flags, u32 bit, int set);
605 	/* Return 0 if OK with change, else return non-zero */
606 	int			(*flag_changed)(struct trace_array *tr,
607 						u32 mask, int set);
608 	struct tracer		*next;
609 	struct tracer_flags	*flags;
610 	int			enabled;
611 	bool			print_max;
612 	bool			allow_instances;
613 #ifdef CONFIG_TRACER_MAX_TRACE
614 	bool			use_max_tr;
615 #endif
616 	/* True if tracer cannot be enabled in kernel param */
617 	bool			noboot;
618 };
619 
620 static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)621 trace_buffer_iter(struct trace_iterator *iter, int cpu)
622 {
623 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
624 }
625 
626 int tracer_init(struct tracer *t, struct trace_array *tr);
627 int tracing_is_enabled(void);
628 void tracing_reset_online_cpus(struct array_buffer *buf);
629 void tracing_reset_all_online_cpus(void);
630 void tracing_reset_all_online_cpus_unlocked(void);
631 int tracing_open_generic(struct inode *inode, struct file *filp);
632 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
633 int tracing_release_generic_tr(struct inode *inode, struct file *file);
634 int tracing_open_file_tr(struct inode *inode, struct file *filp);
635 int tracing_release_file_tr(struct inode *inode, struct file *filp);
636 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
637 bool tracing_is_disabled(void);
638 bool tracer_tracing_is_on(struct trace_array *tr);
639 void tracer_tracing_on(struct trace_array *tr);
640 void tracer_tracing_off(struct trace_array *tr);
641 struct dentry *trace_create_file(const char *name,
642 				 umode_t mode,
643 				 struct dentry *parent,
644 				 void *data,
645 				 const struct file_operations *fops);
646 
647 int tracing_init_dentry(void);
648 
649 struct ring_buffer_event;
650 
651 struct ring_buffer_event *
652 trace_buffer_lock_reserve(struct trace_buffer *buffer,
653 			  int type,
654 			  unsigned long len,
655 			  unsigned int trace_ctx);
656 
657 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
658 
659 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
660 						struct trace_array_cpu *data);
661 
662 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
663 					  int *ent_cpu, u64 *ent_ts);
664 
665 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
666 					struct ring_buffer_event *event);
667 
668 bool trace_is_tracepoint_string(const char *str);
669 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
670 char *trace_iter_expand_format(struct trace_iterator *iter);
671 bool ignore_event(struct trace_iterator *iter);
672 
673 int trace_empty(struct trace_iterator *iter);
674 
675 void *trace_find_next_entry_inc(struct trace_iterator *iter);
676 
677 void trace_init_global_iter(struct trace_iterator *iter);
678 
679 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
680 
681 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
682 unsigned long trace_total_entries(struct trace_array *tr);
683 
684 void trace_function(struct trace_array *tr,
685 		    unsigned long ip,
686 		    unsigned long parent_ip,
687 		    unsigned int trace_ctx);
688 void trace_graph_function(struct trace_array *tr,
689 		    unsigned long ip,
690 		    unsigned long parent_ip,
691 		    unsigned int trace_ctx);
692 void trace_latency_header(struct seq_file *m);
693 void trace_default_header(struct seq_file *m);
694 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
695 
696 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
697 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
698 
699 void tracing_start_cmdline_record(void);
700 void tracing_stop_cmdline_record(void);
701 void tracing_start_tgid_record(void);
702 void tracing_stop_tgid_record(void);
703 
704 int register_tracer(struct tracer *type);
705 int is_tracing_stopped(void);
706 
707 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
708 
709 extern cpumask_var_t __read_mostly tracing_buffer_mask;
710 
711 #define for_each_tracing_cpu(cpu)	\
712 	for_each_cpu(cpu, tracing_buffer_mask)
713 
714 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
715 
716 extern unsigned long tracing_thresh;
717 
718 /* PID filtering */
719 
720 extern int pid_max;
721 
722 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
723 			     pid_t search_pid);
724 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
725 			    struct trace_pid_list *filtered_no_pids,
726 			    struct task_struct *task);
727 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
728 				  struct task_struct *self,
729 				  struct task_struct *task);
730 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
731 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
732 int trace_pid_show(struct seq_file *m, void *v);
733 int trace_pid_write(struct trace_pid_list *filtered_pids,
734 		    struct trace_pid_list **new_pid_list,
735 		    const char __user *ubuf, size_t cnt);
736 
737 #ifdef CONFIG_TRACER_MAX_TRACE
738 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
739 		   void *cond_data);
740 void update_max_tr_single(struct trace_array *tr,
741 			  struct task_struct *tsk, int cpu);
742 
743 #ifdef CONFIG_FSNOTIFY
744 #define LATENCY_FS_NOTIFY
745 #endif
746 #endif /* CONFIG_TRACER_MAX_TRACE */
747 
748 #ifdef LATENCY_FS_NOTIFY
749 void latency_fsnotify(struct trace_array *tr);
750 #else
latency_fsnotify(struct trace_array * tr)751 static inline void latency_fsnotify(struct trace_array *tr) { }
752 #endif
753 
754 #ifdef CONFIG_STACKTRACE
755 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
756 #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)757 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
758 				 int skip)
759 {
760 }
761 #endif /* CONFIG_STACKTRACE */
762 
763 void trace_last_func_repeats(struct trace_array *tr,
764 			     struct trace_func_repeats *last_info,
765 			     unsigned int trace_ctx);
766 
767 extern u64 ftrace_now(int cpu);
768 
769 extern void trace_find_cmdline(int pid, char comm[]);
770 extern int trace_find_tgid(int pid);
771 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
772 
773 #ifdef CONFIG_DYNAMIC_FTRACE
774 extern unsigned long ftrace_update_tot_cnt;
775 extern unsigned long ftrace_number_of_pages;
776 extern unsigned long ftrace_number_of_groups;
777 extern u64 ftrace_update_time;
778 extern u64 ftrace_total_mod_time;
779 void ftrace_init_trace_array(struct trace_array *tr);
780 #else
ftrace_init_trace_array(struct trace_array * tr)781 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
782 #endif
783 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
784 extern int DYN_FTRACE_TEST_NAME(void);
785 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
786 extern int DYN_FTRACE_TEST_NAME2(void);
787 
788 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
789 extern bool tracing_selftest_disabled;
790 
791 #ifdef CONFIG_FTRACE_STARTUP_TEST
792 extern void __init disable_tracing_selftest(const char *reason);
793 
794 extern int trace_selftest_startup_function(struct tracer *trace,
795 					   struct trace_array *tr);
796 extern int trace_selftest_startup_function_graph(struct tracer *trace,
797 						 struct trace_array *tr);
798 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
799 					  struct trace_array *tr);
800 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
801 					     struct trace_array *tr);
802 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
803 						 struct trace_array *tr);
804 extern int trace_selftest_startup_wakeup(struct tracer *trace,
805 					 struct trace_array *tr);
806 extern int trace_selftest_startup_nop(struct tracer *trace,
807 					 struct trace_array *tr);
808 extern int trace_selftest_startup_branch(struct tracer *trace,
809 					 struct trace_array *tr);
810 /*
811  * Tracer data references selftest functions that only occur
812  * on boot up. These can be __init functions. Thus, when selftests
813  * are enabled, then the tracers need to reference __init functions.
814  */
815 #define __tracer_data		__refdata
816 #else
disable_tracing_selftest(const char * reason)817 static inline void __init disable_tracing_selftest(const char *reason)
818 {
819 }
820 /* Tracers are seldom changed. Optimize when selftests are disabled. */
821 #define __tracer_data		__read_mostly
822 #endif /* CONFIG_FTRACE_STARTUP_TEST */
823 
824 extern void *head_page(struct trace_array_cpu *data);
825 extern unsigned long long ns2usecs(u64 nsec);
826 extern int
827 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
828 extern int
829 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
830 extern int
831 trace_array_vprintk(struct trace_array *tr,
832 		    unsigned long ip, const char *fmt, va_list args);
833 int trace_array_printk_buf(struct trace_buffer *buffer,
834 			   unsigned long ip, const char *fmt, ...);
835 void trace_printk_seq(struct trace_seq *s);
836 enum print_line_t print_trace_line(struct trace_iterator *iter);
837 
838 extern char trace_find_mark(unsigned long long duration);
839 
840 struct ftrace_hash;
841 
842 struct ftrace_mod_load {
843 	struct list_head	list;
844 	char			*func;
845 	char			*module;
846 	int			 enable;
847 };
848 
849 enum {
850 	FTRACE_HASH_FL_MOD	= (1 << 0),
851 };
852 
853 struct ftrace_hash {
854 	unsigned long		size_bits;
855 	struct hlist_head	*buckets;
856 	unsigned long		count;
857 	unsigned long		flags;
858 	struct rcu_head		rcu;
859 };
860 
861 struct ftrace_func_entry *
862 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
863 
ftrace_hash_empty(struct ftrace_hash * hash)864 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
865 {
866 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
867 }
868 
869 /* Standard output formatting function used for function return traces */
870 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
871 
872 /* Flag options */
873 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
874 #define TRACE_GRAPH_PRINT_CPU           0x2
875 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
876 #define TRACE_GRAPH_PRINT_PROC          0x8
877 #define TRACE_GRAPH_PRINT_DURATION      0x10
878 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
879 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
880 #define TRACE_GRAPH_PRINT_IRQS          0x80
881 #define TRACE_GRAPH_PRINT_TAIL          0x100
882 #define TRACE_GRAPH_SLEEP_TIME          0x200
883 #define TRACE_GRAPH_GRAPH_TIME          0x400
884 #define TRACE_GRAPH_PRINT_RETVAL        0x800
885 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
886 #define TRACE_GRAPH_PRINT_RETADDR       0x2000
887 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
888 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
889 
890 extern void ftrace_graph_sleep_time_control(bool enable);
891 
892 #ifdef CONFIG_FUNCTION_PROFILER
893 extern void ftrace_graph_graph_time_control(bool enable);
894 #else
ftrace_graph_graph_time_control(bool enable)895 static inline void ftrace_graph_graph_time_control(bool enable) { }
896 #endif
897 
898 extern enum print_line_t
899 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
900 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
901 extern void
902 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
903 extern void graph_trace_open(struct trace_iterator *iter);
904 extern void graph_trace_close(struct trace_iterator *iter);
905 extern int __trace_graph_entry(struct trace_array *tr,
906 			       struct ftrace_graph_ent *trace,
907 			       unsigned int trace_ctx);
908 extern int __trace_graph_retaddr_entry(struct trace_array *tr,
909 				struct ftrace_graph_ent *trace,
910 				unsigned int trace_ctx,
911 				unsigned long retaddr);
912 extern void __trace_graph_return(struct trace_array *tr,
913 				 struct ftrace_graph_ret *trace,
914 				 unsigned int trace_ctx);
915 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
916 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
917 extern void free_fgraph_ops(struct trace_array *tr);
918 
919 enum {
920 	TRACE_GRAPH_FL		= 1,
921 
922 	/*
923 	 * In the very unlikely case that an interrupt came in
924 	 * at a start of graph tracing, and we want to trace
925 	 * the function in that interrupt, the depth can be greater
926 	 * than zero, because of the preempted start of a previous
927 	 * trace. In an even more unlikely case, depth could be 2
928 	 * if a softirq interrupted the start of graph tracing,
929 	 * followed by an interrupt preempting a start of graph
930 	 * tracing in the softirq, and depth can even be 3
931 	 * if an NMI came in at the start of an interrupt function
932 	 * that preempted a softirq start of a function that
933 	 * preempted normal context!!!! Luckily, it can't be
934 	 * greater than 3, so the next two bits are a mask
935 	 * of what the depth is when we set TRACE_GRAPH_FL
936 	 */
937 
938 	TRACE_GRAPH_DEPTH_START_BIT,
939 	TRACE_GRAPH_DEPTH_END_BIT,
940 
941 	/*
942 	 * To implement set_graph_notrace, if this bit is set, we ignore
943 	 * function graph tracing of called functions, until the return
944 	 * function is called to clear it.
945 	 */
946 	TRACE_GRAPH_NOTRACE_BIT,
947 };
948 
949 #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
950 
ftrace_graph_depth(unsigned long * task_var)951 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
952 {
953 	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
954 }
955 
ftrace_graph_set_depth(unsigned long * task_var,int depth)956 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
957 {
958 	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
959 	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
960 }
961 
962 #ifdef CONFIG_DYNAMIC_FTRACE
963 extern struct ftrace_hash __rcu *ftrace_graph_hash;
964 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
965 
966 static inline int
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)967 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
968 {
969 	unsigned long addr = trace->func;
970 	int ret = 0;
971 	struct ftrace_hash *hash;
972 
973 	preempt_disable_notrace();
974 
975 	/*
976 	 * Have to open code "rcu_dereference_sched()" because the
977 	 * function graph tracer can be called when RCU is not
978 	 * "watching".
979 	 * Protected with schedule_on_each_cpu(ftrace_sync)
980 	 */
981 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
982 
983 	if (ftrace_hash_empty(hash)) {
984 		ret = 1;
985 		goto out;
986 	}
987 
988 	if (ftrace_lookup_ip(hash, addr)) {
989 		/*
990 		 * This needs to be cleared on the return functions
991 		 * when the depth is zero.
992 		 */
993 		*task_var |= TRACE_GRAPH_FL;
994 		ftrace_graph_set_depth(task_var, trace->depth);
995 
996 		/*
997 		 * If no irqs are to be traced, but a set_graph_function
998 		 * is set, and called by an interrupt handler, we still
999 		 * want to trace it.
1000 		 */
1001 		if (in_hardirq())
1002 			trace_recursion_set(TRACE_IRQ_BIT);
1003 		else
1004 			trace_recursion_clear(TRACE_IRQ_BIT);
1005 		ret = 1;
1006 	}
1007 
1008 out:
1009 	preempt_enable_notrace();
1010 	return ret;
1011 }
1012 
1013 static inline void
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1014 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1015 {
1016 	unsigned long *task_var = fgraph_get_task_var(gops);
1017 
1018 	if ((*task_var & TRACE_GRAPH_FL) &&
1019 	    trace->depth == ftrace_graph_depth(task_var))
1020 		*task_var &= ~TRACE_GRAPH_FL;
1021 }
1022 
ftrace_graph_notrace_addr(unsigned long addr)1023 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1024 {
1025 	int ret = 0;
1026 	struct ftrace_hash *notrace_hash;
1027 
1028 	preempt_disable_notrace();
1029 
1030 	/*
1031 	 * Have to open code "rcu_dereference_sched()" because the
1032 	 * function graph tracer can be called when RCU is not
1033 	 * "watching".
1034 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1035 	 */
1036 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1037 						 !preemptible());
1038 
1039 	if (ftrace_lookup_ip(notrace_hash, addr))
1040 		ret = 1;
1041 
1042 	preempt_enable_notrace();
1043 	return ret;
1044 }
1045 #else
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)1046 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1047 {
1048 	return 1;
1049 }
1050 
ftrace_graph_notrace_addr(unsigned long addr)1051 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1052 {
1053 	return 0;
1054 }
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1055 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1056 { }
1057 #endif /* CONFIG_DYNAMIC_FTRACE */
1058 
1059 extern unsigned int fgraph_max_depth;
1060 extern bool fgraph_sleep_time;
1061 
1062 static inline bool
ftrace_graph_ignore_func(struct fgraph_ops * gops,struct ftrace_graph_ent * trace)1063 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1064 {
1065 	unsigned long *task_var = fgraph_get_task_var(gops);
1066 
1067 	/* trace it when it is-nested-in or is a function enabled. */
1068 	return !((*task_var & TRACE_GRAPH_FL) ||
1069 		 ftrace_graph_addr(task_var, trace)) ||
1070 		(trace->depth < 0) ||
1071 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1072 }
1073 
1074 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1075 		     struct ftrace_ops *src_ops);
1076 
1077 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1078 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)1079 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1080 {
1081 	return TRACE_TYPE_UNHANDLED;
1082 }
free_fgraph_ops(struct trace_array * tr)1083 static inline void free_fgraph_ops(struct trace_array *tr) { }
1084 /* ftrace_ops may not be defined */
1085 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1086 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1087 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1088 
1089 extern struct list_head ftrace_pids;
1090 
1091 #ifdef CONFIG_FUNCTION_TRACER
1092 
1093 #define FTRACE_PID_IGNORE	-1
1094 #define FTRACE_PID_TRACE	-2
1095 
1096 struct ftrace_func_command {
1097 	struct list_head	list;
1098 	char			*name;
1099 	int			(*func)(struct trace_array *tr,
1100 					struct ftrace_hash *hash,
1101 					char *func, char *cmd,
1102 					char *params, int enable);
1103 };
1104 extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)1105 static inline int ftrace_trace_task(struct trace_array *tr)
1106 {
1107 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1108 		FTRACE_PID_IGNORE;
1109 }
1110 extern int ftrace_is_dead(void);
1111 int ftrace_create_function_files(struct trace_array *tr,
1112 				 struct dentry *parent);
1113 void ftrace_destroy_function_files(struct trace_array *tr);
1114 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1115 void ftrace_free_ftrace_ops(struct trace_array *tr);
1116 void ftrace_init_global_array_ops(struct trace_array *tr);
1117 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1118 void ftrace_reset_array_ops(struct trace_array *tr);
1119 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1120 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1121 				  struct dentry *d_tracer);
1122 void ftrace_clear_pids(struct trace_array *tr);
1123 int init_function_trace(void);
1124 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1125 #else
ftrace_trace_task(struct trace_array * tr)1126 static inline int ftrace_trace_task(struct trace_array *tr)
1127 {
1128 	return 1;
1129 }
ftrace_is_dead(void)1130 static inline int ftrace_is_dead(void) { return 0; }
1131 static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1132 ftrace_create_function_files(struct trace_array *tr,
1133 			     struct dentry *parent)
1134 {
1135 	return 0;
1136 }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1137 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1138 {
1139 	return 0;
1140 }
ftrace_free_ftrace_ops(struct trace_array * tr)1141 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1142 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1143 static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1144 ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1145 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1146 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1147 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1148 static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1149 static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1150 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1151 /* ftace_func_t type is not defined, use macro instead of static inline */
1152 #define ftrace_init_array_ops(tr, func) do { } while (0)
1153 #endif /* CONFIG_FUNCTION_TRACER */
1154 
1155 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1156 
1157 struct ftrace_probe_ops {
1158 	void			(*func)(unsigned long ip,
1159 					unsigned long parent_ip,
1160 					struct trace_array *tr,
1161 					struct ftrace_probe_ops *ops,
1162 					void *data);
1163 	int			(*init)(struct ftrace_probe_ops *ops,
1164 					struct trace_array *tr,
1165 					unsigned long ip, void *init_data,
1166 					void **data);
1167 	void			(*free)(struct ftrace_probe_ops *ops,
1168 					struct trace_array *tr,
1169 					unsigned long ip, void *data);
1170 	int			(*print)(struct seq_file *m,
1171 					 unsigned long ip,
1172 					 struct ftrace_probe_ops *ops,
1173 					 void *data);
1174 };
1175 
1176 struct ftrace_func_mapper;
1177 typedef int (*ftrace_mapper_func)(void *data);
1178 
1179 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1180 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1181 					   unsigned long ip);
1182 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1183 			       unsigned long ip, void *data);
1184 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1185 				   unsigned long ip);
1186 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1187 			     ftrace_mapper_func free_func);
1188 
1189 extern int
1190 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1191 			       struct ftrace_probe_ops *ops, void *data);
1192 extern int
1193 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1194 				      struct ftrace_probe_ops *ops);
1195 extern void clear_ftrace_function_probes(struct trace_array *tr);
1196 
1197 int register_ftrace_command(struct ftrace_func_command *cmd);
1198 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1199 
1200 void ftrace_create_filter_files(struct ftrace_ops *ops,
1201 				struct dentry *parent);
1202 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1203 
1204 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1205 			     int len, int reset);
1206 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1207 			      int len, int reset);
1208 #else
1209 struct ftrace_func_command;
1210 
register_ftrace_command(struct ftrace_func_command * cmd)1211 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1212 {
1213 	return -EINVAL;
1214 }
unregister_ftrace_command(char * cmd_name)1215 static inline __init int unregister_ftrace_command(char *cmd_name)
1216 {
1217 	return -EINVAL;
1218 }
clear_ftrace_function_probes(struct trace_array * tr)1219 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1220 {
1221 }
1222 
1223 /*
1224  * The ops parameter passed in is usually undefined.
1225  * This must be a macro.
1226  */
1227 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1228 #define ftrace_destroy_filter_files(ops) do { } while (0)
1229 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1230 
1231 bool ftrace_event_is_function(struct trace_event_call *call);
1232 
1233 /*
1234  * struct trace_parser - servers for reading the user input separated by spaces
1235  * @cont: set if the input is not complete - no final space char was found
1236  * @buffer: holds the parsed user input
1237  * @idx: user input length
1238  * @size: buffer size
1239  */
1240 struct trace_parser {
1241 	bool		cont;
1242 	char		*buffer;
1243 	unsigned	idx;
1244 	unsigned	size;
1245 };
1246 
trace_parser_loaded(struct trace_parser * parser)1247 static inline bool trace_parser_loaded(struct trace_parser *parser)
1248 {
1249 	return (parser->idx != 0);
1250 }
1251 
trace_parser_cont(struct trace_parser * parser)1252 static inline bool trace_parser_cont(struct trace_parser *parser)
1253 {
1254 	return parser->cont;
1255 }
1256 
trace_parser_clear(struct trace_parser * parser)1257 static inline void trace_parser_clear(struct trace_parser *parser)
1258 {
1259 	parser->cont = false;
1260 	parser->idx = 0;
1261 }
1262 
1263 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1264 extern void trace_parser_put(struct trace_parser *parser);
1265 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1266 	size_t cnt, loff_t *ppos);
1267 
1268 /*
1269  * Only create function graph options if function graph is configured.
1270  */
1271 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1272 # define FGRAPH_FLAGS						\
1273 		C(DISPLAY_GRAPH,	"display-graph"),
1274 #else
1275 # define FGRAPH_FLAGS
1276 #endif
1277 
1278 #ifdef CONFIG_BRANCH_TRACER
1279 # define BRANCH_FLAGS					\
1280 		C(BRANCH,		"branch"),
1281 #else
1282 # define BRANCH_FLAGS
1283 #endif
1284 
1285 #ifdef CONFIG_FUNCTION_TRACER
1286 # define FUNCTION_FLAGS						\
1287 		C(FUNCTION,		"function-trace"),	\
1288 		C(FUNC_FORK,		"function-fork"),
1289 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1290 #else
1291 # define FUNCTION_FLAGS
1292 # define FUNCTION_DEFAULT_FLAGS		0UL
1293 # define TRACE_ITER_FUNC_FORK		0UL
1294 #endif
1295 
1296 #ifdef CONFIG_STACKTRACE
1297 # define STACK_FLAGS				\
1298 		C(STACKTRACE,		"stacktrace"),
1299 #else
1300 # define STACK_FLAGS
1301 #endif
1302 
1303 /*
1304  * trace_iterator_flags is an enumeration that defines bit
1305  * positions into trace_flags that controls the output.
1306  *
1307  * NOTE: These bits must match the trace_options array in
1308  *       trace.c (this macro guarantees it).
1309  */
1310 #define TRACE_FLAGS						\
1311 		C(PRINT_PARENT,		"print-parent"),	\
1312 		C(SYM_OFFSET,		"sym-offset"),		\
1313 		C(SYM_ADDR,		"sym-addr"),		\
1314 		C(VERBOSE,		"verbose"),		\
1315 		C(RAW,			"raw"),			\
1316 		C(HEX,			"hex"),			\
1317 		C(BIN,			"bin"),			\
1318 		C(BLOCK,		"block"),		\
1319 		C(FIELDS,		"fields"),		\
1320 		C(PRINTK,		"trace_printk"),	\
1321 		C(ANNOTATE,		"annotate"),		\
1322 		C(USERSTACKTRACE,	"userstacktrace"),	\
1323 		C(SYM_USEROBJ,		"sym-userobj"),		\
1324 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1325 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1326 		C(LATENCY_FMT,		"latency-format"),	\
1327 		C(RECORD_CMD,		"record-cmd"),		\
1328 		C(RECORD_TGID,		"record-tgid"),		\
1329 		C(OVERWRITE,		"overwrite"),		\
1330 		C(STOP_ON_FREE,		"disable_on_free"),	\
1331 		C(IRQ_INFO,		"irq-info"),		\
1332 		C(MARKERS,		"markers"),		\
1333 		C(EVENT_FORK,		"event-fork"),		\
1334 		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1335 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1336 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1337 		FUNCTION_FLAGS					\
1338 		FGRAPH_FLAGS					\
1339 		STACK_FLAGS					\
1340 		BRANCH_FLAGS
1341 
1342 /*
1343  * By defining C, we can make TRACE_FLAGS a list of bit names
1344  * that will define the bits for the flag masks.
1345  */
1346 #undef C
1347 #define C(a, b) TRACE_ITER_##a##_BIT
1348 
1349 enum trace_iterator_bits {
1350 	TRACE_FLAGS
1351 	/* Make sure we don't go more than we have bits for */
1352 	TRACE_ITER_LAST_BIT
1353 };
1354 
1355 /*
1356  * By redefining C, we can make TRACE_FLAGS a list of masks that
1357  * use the bits as defined above.
1358  */
1359 #undef C
1360 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1361 
1362 enum trace_iterator_flags { TRACE_FLAGS };
1363 
1364 /*
1365  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1366  * control the output of kernel symbols.
1367  */
1368 #define TRACE_ITER_SYM_MASK \
1369 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1370 
1371 extern struct tracer nop_trace;
1372 
1373 #ifdef CONFIG_BRANCH_TRACER
1374 extern int enable_branch_tracing(struct trace_array *tr);
1375 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1376 static inline int trace_branch_enable(struct trace_array *tr)
1377 {
1378 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1379 		return enable_branch_tracing(tr);
1380 	return 0;
1381 }
trace_branch_disable(void)1382 static inline void trace_branch_disable(void)
1383 {
1384 	/* due to races, always disable */
1385 	disable_branch_tracing();
1386 }
1387 #else
trace_branch_enable(struct trace_array * tr)1388 static inline int trace_branch_enable(struct trace_array *tr)
1389 {
1390 	return 0;
1391 }
trace_branch_disable(void)1392 static inline void trace_branch_disable(void)
1393 {
1394 }
1395 #endif /* CONFIG_BRANCH_TRACER */
1396 
1397 /* set ring buffers to default size if not already done so */
1398 int tracing_update_buffers(struct trace_array *tr);
1399 
1400 union trace_synth_field {
1401 	u8				as_u8;
1402 	u16				as_u16;
1403 	u32				as_u32;
1404 	u64				as_u64;
1405 	struct trace_dynamic_info	as_dynamic;
1406 };
1407 
1408 struct ftrace_event_field {
1409 	struct list_head	link;
1410 	const char		*name;
1411 	const char		*type;
1412 	int			filter_type;
1413 	int			offset;
1414 	int			size;
1415 	unsigned int		is_signed:1;
1416 	unsigned int		needs_test:1;
1417 	int			len;
1418 };
1419 
1420 struct prog_entry;
1421 
1422 struct event_filter {
1423 	struct prog_entry __rcu	*prog;
1424 	char			*filter_string;
1425 };
1426 
1427 struct event_subsystem {
1428 	struct list_head	list;
1429 	const char		*name;
1430 	struct event_filter	*filter;
1431 	int			ref_count;
1432 };
1433 
1434 struct trace_subsystem_dir {
1435 	struct list_head		list;
1436 	struct event_subsystem		*subsystem;
1437 	struct trace_array		*tr;
1438 	struct eventfs_inode		*ei;
1439 	int				ref_count;
1440 	int				nr_events;
1441 };
1442 
1443 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1444 				     struct trace_buffer *buffer,
1445 				     struct ring_buffer_event *event,
1446 				     unsigned int trcace_ctx,
1447 				     struct pt_regs *regs);
1448 
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1449 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1450 					      struct trace_buffer *buffer,
1451 					      struct ring_buffer_event *event,
1452 					      unsigned int trace_ctx)
1453 {
1454 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1455 }
1456 
1457 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1458 int trace_save_cmdline(struct task_struct *tsk);
1459 int trace_create_savedcmd(void);
1460 int trace_alloc_tgid_map(void);
1461 void trace_free_saved_cmdlines_buffer(void);
1462 
1463 extern const struct file_operations tracing_saved_cmdlines_fops;
1464 extern const struct file_operations tracing_saved_tgids_fops;
1465 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1466 
1467 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1468 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1469 void trace_buffered_event_disable(void);
1470 void trace_buffered_event_enable(void);
1471 
1472 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1473 
1474 static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1475 __trace_event_discard_commit(struct trace_buffer *buffer,
1476 			     struct ring_buffer_event *event)
1477 {
1478 	if (this_cpu_read(trace_buffered_event) == event) {
1479 		/* Simply release the temp buffer and enable preemption */
1480 		this_cpu_dec(trace_buffered_event_cnt);
1481 		preempt_enable_notrace();
1482 		return;
1483 	}
1484 	/* ring_buffer_discard_commit() enables preemption */
1485 	ring_buffer_discard_commit(buffer, event);
1486 }
1487 
1488 /*
1489  * Helper function for event_trigger_unlock_commit{_regs}().
1490  * If there are event triggers attached to this event that requires
1491  * filtering against its fields, then they will be called as the
1492  * entry already holds the field information of the current event.
1493  *
1494  * It also checks if the event should be discarded or not.
1495  * It is to be discarded if the event is soft disabled and the
1496  * event was only recorded to process triggers, or if the event
1497  * filter is active and this event did not match the filters.
1498  *
1499  * Returns true if the event is discarded, false otherwise.
1500  */
1501 static inline bool
__event_trigger_test_discard(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,enum event_trigger_type * tt)1502 __event_trigger_test_discard(struct trace_event_file *file,
1503 			     struct trace_buffer *buffer,
1504 			     struct ring_buffer_event *event,
1505 			     void *entry,
1506 			     enum event_trigger_type *tt)
1507 {
1508 	unsigned long eflags = file->flags;
1509 
1510 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1511 		*tt = event_triggers_call(file, buffer, entry, event);
1512 
1513 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1514 				    EVENT_FILE_FL_FILTERED |
1515 				    EVENT_FILE_FL_PID_FILTER))))
1516 		return false;
1517 
1518 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1519 		goto discard;
1520 
1521 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1522 	    !filter_match_preds(file->filter, entry))
1523 		goto discard;
1524 
1525 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1526 	    trace_event_ignore_this_pid(file))
1527 		goto discard;
1528 
1529 	return false;
1530  discard:
1531 	__trace_event_discard_commit(buffer, event);
1532 	return true;
1533 }
1534 
1535 /**
1536  * event_trigger_unlock_commit - handle triggers and finish event commit
1537  * @file: The file pointer associated with the event
1538  * @buffer: The ring buffer that the event is being written to
1539  * @event: The event meta data in the ring buffer
1540  * @entry: The event itself
1541  * @trace_ctx: The tracing context flags.
1542  *
1543  * This is a helper function to handle triggers that require data
1544  * from the event itself. It also tests the event against filters and
1545  * if the event is soft disabled and should be discarded.
1546  */
1547 static inline void
event_trigger_unlock_commit(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,unsigned int trace_ctx)1548 event_trigger_unlock_commit(struct trace_event_file *file,
1549 			    struct trace_buffer *buffer,
1550 			    struct ring_buffer_event *event,
1551 			    void *entry, unsigned int trace_ctx)
1552 {
1553 	enum event_trigger_type tt = ETT_NONE;
1554 
1555 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1556 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1557 
1558 	if (tt)
1559 		event_triggers_post_call(file, tt);
1560 }
1561 
1562 #define FILTER_PRED_INVALID	((unsigned short)-1)
1563 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1564 #define FILTER_PRED_FOLD	(1 << 15)
1565 
1566 /*
1567  * The max preds is the size of unsigned short with
1568  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1569  * and FOLD flags. The other is reserved.
1570  *
1571  * 2^14 preds is way more than enough.
1572  */
1573 #define MAX_FILTER_PRED		16384
1574 
1575 struct filter_pred;
1576 struct regex;
1577 
1578 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1579 
1580 enum regex_type {
1581 	MATCH_FULL = 0,
1582 	MATCH_FRONT_ONLY,
1583 	MATCH_MIDDLE_ONLY,
1584 	MATCH_END_ONLY,
1585 	MATCH_GLOB,
1586 	MATCH_INDEX,
1587 };
1588 
1589 struct regex {
1590 	char			pattern[MAX_FILTER_STR_VAL];
1591 	int			len;
1592 	int			field_len;
1593 	regex_match_func	match;
1594 };
1595 
is_string_field(struct ftrace_event_field * field)1596 static inline bool is_string_field(struct ftrace_event_field *field)
1597 {
1598 	return field->filter_type == FILTER_DYN_STRING ||
1599 	       field->filter_type == FILTER_RDYN_STRING ||
1600 	       field->filter_type == FILTER_STATIC_STRING ||
1601 	       field->filter_type == FILTER_PTR_STRING ||
1602 	       field->filter_type == FILTER_COMM;
1603 }
1604 
is_function_field(struct ftrace_event_field * field)1605 static inline bool is_function_field(struct ftrace_event_field *field)
1606 {
1607 	return field->filter_type == FILTER_TRACE_FN;
1608 }
1609 
1610 extern enum regex_type
1611 filter_parse_regex(char *buff, int len, char **search, int *not);
1612 extern void print_event_filter(struct trace_event_file *file,
1613 			       struct trace_seq *s);
1614 extern int apply_event_filter(struct trace_event_file *file,
1615 			      char *filter_string);
1616 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1617 					char *filter_string);
1618 extern void print_subsystem_event_filter(struct event_subsystem *system,
1619 					 struct trace_seq *s);
1620 extern int filter_assign_type(const char *type);
1621 extern int create_event_filter(struct trace_array *tr,
1622 			       struct trace_event_call *call,
1623 			       char *filter_str, bool set_str,
1624 			       struct event_filter **filterp);
1625 extern void free_event_filter(struct event_filter *filter);
1626 
1627 struct ftrace_event_field *
1628 trace_find_event_field(struct trace_event_call *call, char *name);
1629 
1630 extern void trace_event_enable_cmd_record(bool enable);
1631 extern void trace_event_enable_tgid_record(bool enable);
1632 
1633 extern int event_trace_init(void);
1634 extern int init_events(void);
1635 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1636 extern int event_trace_del_tracer(struct trace_array *tr);
1637 extern void __trace_early_add_events(struct trace_array *tr);
1638 
1639 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1640 						  const char *system,
1641 						  const char *event);
1642 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1643 						const char *system,
1644 						const char *event);
1645 
event_file_data(struct file * filp)1646 static inline void *event_file_data(struct file *filp)
1647 {
1648 	return READ_ONCE(file_inode(filp)->i_private);
1649 }
1650 
1651 extern struct mutex event_mutex;
1652 extern struct list_head ftrace_events;
1653 
1654 /*
1655  * When the trace_event_file is the filp->i_private pointer,
1656  * it must be taken under the event_mutex lock, and then checked
1657  * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1658  * data pointed to by the trace_event_file can not be trusted.
1659  *
1660  * Use the event_file_file() to access the trace_event_file from
1661  * the filp the first time under the event_mutex and check for
1662  * NULL. If it is needed to be retrieved again and the event_mutex
1663  * is still held, then the event_file_data() can be used and it
1664  * is guaranteed to be valid.
1665  */
event_file_file(struct file * filp)1666 static inline struct trace_event_file *event_file_file(struct file *filp)
1667 {
1668 	struct trace_event_file *file;
1669 
1670 	lockdep_assert_held(&event_mutex);
1671 	file = READ_ONCE(file_inode(filp)->i_private);
1672 	if (!file || file->flags & EVENT_FILE_FL_FREED)
1673 		return NULL;
1674 	return file;
1675 }
1676 
1677 extern const struct file_operations event_trigger_fops;
1678 extern const struct file_operations event_hist_fops;
1679 extern const struct file_operations event_hist_debug_fops;
1680 extern const struct file_operations event_inject_fops;
1681 
1682 #ifdef CONFIG_HIST_TRIGGERS
1683 extern int register_trigger_hist_cmd(void);
1684 extern int register_trigger_hist_enable_disable_cmds(void);
1685 #else
register_trigger_hist_cmd(void)1686 static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1687 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1688 #endif
1689 
1690 extern int register_trigger_cmds(void);
1691 extern void clear_event_triggers(struct trace_array *tr);
1692 
1693 enum {
1694 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1695 };
1696 
1697 struct event_trigger_data {
1698 	unsigned long			count;
1699 	int				ref;
1700 	int				flags;
1701 	struct event_trigger_ops	*ops;
1702 	struct event_command		*cmd_ops;
1703 	struct event_filter __rcu	*filter;
1704 	char				*filter_str;
1705 	void				*private_data;
1706 	bool				paused;
1707 	bool				paused_tmp;
1708 	struct list_head		list;
1709 	char				*name;
1710 	struct list_head		named_list;
1711 	struct event_trigger_data	*named_data;
1712 };
1713 
1714 /* Avoid typos */
1715 #define ENABLE_EVENT_STR	"enable_event"
1716 #define DISABLE_EVENT_STR	"disable_event"
1717 #define ENABLE_HIST_STR		"enable_hist"
1718 #define DISABLE_HIST_STR	"disable_hist"
1719 
1720 struct enable_trigger_data {
1721 	struct trace_event_file		*file;
1722 	bool				enable;
1723 	bool				hist;
1724 };
1725 
1726 extern int event_enable_trigger_print(struct seq_file *m,
1727 				      struct event_trigger_data *data);
1728 extern void event_enable_trigger_free(struct event_trigger_data *data);
1729 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1730 				      struct trace_event_file *file,
1731 				      char *glob, char *cmd,
1732 				      char *param_and_filter);
1733 extern int event_enable_register_trigger(char *glob,
1734 					 struct event_trigger_data *data,
1735 					 struct trace_event_file *file);
1736 extern void event_enable_unregister_trigger(char *glob,
1737 					    struct event_trigger_data *test,
1738 					    struct trace_event_file *file);
1739 extern void trigger_data_free(struct event_trigger_data *data);
1740 extern int event_trigger_init(struct event_trigger_data *data);
1741 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1742 					      int trigger_enable);
1743 extern void update_cond_flag(struct trace_event_file *file);
1744 extern int set_trigger_filter(char *filter_str,
1745 			      struct event_trigger_data *trigger_data,
1746 			      struct trace_event_file *file);
1747 extern struct event_trigger_data *find_named_trigger(const char *name);
1748 extern bool is_named_trigger(struct event_trigger_data *test);
1749 extern int save_named_trigger(const char *name,
1750 			      struct event_trigger_data *data);
1751 extern void del_named_trigger(struct event_trigger_data *data);
1752 extern void pause_named_trigger(struct event_trigger_data *data);
1753 extern void unpause_named_trigger(struct event_trigger_data *data);
1754 extern void set_named_trigger_data(struct event_trigger_data *data,
1755 				   struct event_trigger_data *named_data);
1756 extern struct event_trigger_data *
1757 get_named_trigger_data(struct event_trigger_data *data);
1758 extern int register_event_command(struct event_command *cmd);
1759 extern int unregister_event_command(struct event_command *cmd);
1760 extern int register_trigger_hist_enable_disable_cmds(void);
1761 extern bool event_trigger_check_remove(const char *glob);
1762 extern bool event_trigger_empty_param(const char *param);
1763 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1764 					 char **filter, bool param_required);
1765 extern struct event_trigger_data *
1766 event_trigger_alloc(struct event_command *cmd_ops,
1767 		    char *cmd,
1768 		    char *param,
1769 		    void *private_data);
1770 extern int event_trigger_parse_num(char *trigger,
1771 				   struct event_trigger_data *trigger_data);
1772 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1773 				    struct trace_event_file *file,
1774 				    char *param,
1775 				    struct event_trigger_data *trigger_data);
1776 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1777 				       struct event_trigger_data *trigger_data);
1778 extern int event_trigger_register(struct event_command *cmd_ops,
1779 				  struct trace_event_file *file,
1780 				  char *glob,
1781 				  struct event_trigger_data *trigger_data);
1782 extern void event_trigger_unregister(struct event_command *cmd_ops,
1783 				     struct trace_event_file *file,
1784 				     char *glob,
1785 				     struct event_trigger_data *trigger_data);
1786 
1787 extern void event_file_get(struct trace_event_file *file);
1788 extern void event_file_put(struct trace_event_file *file);
1789 
1790 /**
1791  * struct event_trigger_ops - callbacks for trace event triggers
1792  *
1793  * The methods in this structure provide per-event trigger hooks for
1794  * various trigger operations.
1795  *
1796  * The @init and @free methods are used during trigger setup and
1797  * teardown, typically called from an event_command's @parse()
1798  * function implementation.
1799  *
1800  * The @print method is used to print the trigger spec.
1801  *
1802  * The @trigger method is the function that actually implements the
1803  * trigger and is called in the context of the triggering event
1804  * whenever that event occurs.
1805  *
1806  * All the methods below, except for @init() and @free(), must be
1807  * implemented.
1808  *
1809  * @trigger: The trigger 'probe' function called when the triggering
1810  *	event occurs.  The data passed into this callback is the data
1811  *	that was supplied to the event_command @reg() function that
1812  *	registered the trigger (see struct event_command) along with
1813  *	the trace record, rec.
1814  *
1815  * @init: An optional initialization function called for the trigger
1816  *	when the trigger is registered (via the event_command reg()
1817  *	function).  This can be used to perform per-trigger
1818  *	initialization such as incrementing a per-trigger reference
1819  *	count, for instance.  This is usually implemented by the
1820  *	generic utility function @event_trigger_init() (see
1821  *	trace_event_triggers.c).
1822  *
1823  * @free: An optional de-initialization function called for the
1824  *	trigger when the trigger is unregistered (via the
1825  *	event_command @reg() function).  This can be used to perform
1826  *	per-trigger de-initialization such as decrementing a
1827  *	per-trigger reference count and freeing corresponding trigger
1828  *	data, for instance.  This is usually implemented by the
1829  *	generic utility function @event_trigger_free() (see
1830  *	trace_event_triggers.c).
1831  *
1832  * @print: The callback function invoked to have the trigger print
1833  *	itself.  This is usually implemented by a wrapper function
1834  *	that calls the generic utility function @event_trigger_print()
1835  *	(see trace_event_triggers.c).
1836  */
1837 struct event_trigger_ops {
1838 	void			(*trigger)(struct event_trigger_data *data,
1839 					   struct trace_buffer *buffer,
1840 					   void *rec,
1841 					   struct ring_buffer_event *rbe);
1842 	int			(*init)(struct event_trigger_data *data);
1843 	void			(*free)(struct event_trigger_data *data);
1844 	int			(*print)(struct seq_file *m,
1845 					 struct event_trigger_data *data);
1846 };
1847 
1848 /**
1849  * struct event_command - callbacks and data members for event commands
1850  *
1851  * Event commands are invoked by users by writing the command name
1852  * into the 'trigger' file associated with a trace event.  The
1853  * parameters associated with a specific invocation of an event
1854  * command are used to create an event trigger instance, which is
1855  * added to the list of trigger instances associated with that trace
1856  * event.  When the event is hit, the set of triggers associated with
1857  * that event is invoked.
1858  *
1859  * The data members in this structure provide per-event command data
1860  * for various event commands.
1861  *
1862  * All the data members below, except for @post_trigger, must be set
1863  * for each event command.
1864  *
1865  * @name: The unique name that identifies the event command.  This is
1866  *	the name used when setting triggers via trigger files.
1867  *
1868  * @trigger_type: A unique id that identifies the event command
1869  *	'type'.  This value has two purposes, the first to ensure that
1870  *	only one trigger of the same type can be set at a given time
1871  *	for a particular event e.g. it doesn't make sense to have both
1872  *	a traceon and traceoff trigger attached to a single event at
1873  *	the same time, so traceon and traceoff have the same type
1874  *	though they have different names.  The @trigger_type value is
1875  *	also used as a bit value for deferring the actual trigger
1876  *	action until after the current event is finished.  Some
1877  *	commands need to do this if they themselves log to the trace
1878  *	buffer (see the @post_trigger() member below).  @trigger_type
1879  *	values are defined by adding new values to the trigger_type
1880  *	enum in include/linux/trace_events.h.
1881  *
1882  * @flags: See the enum event_command_flags below.
1883  *
1884  * All the methods below, except for @set_filter() and @unreg_all(),
1885  * must be implemented.
1886  *
1887  * @parse: The callback function responsible for parsing and
1888  *	registering the trigger written to the 'trigger' file by the
1889  *	user.  It allocates the trigger instance and registers it with
1890  *	the appropriate trace event.  It makes use of the other
1891  *	event_command callback functions to orchestrate this, and is
1892  *	usually implemented by the generic utility function
1893  *	@event_trigger_callback() (see trace_event_triggers.c).
1894  *
1895  * @reg: Adds the trigger to the list of triggers associated with the
1896  *	event, and enables the event trigger itself, after
1897  *	initializing it (via the event_trigger_ops @init() function).
1898  *	This is also where commands can use the @trigger_type value to
1899  *	make the decision as to whether or not multiple instances of
1900  *	the trigger should be allowed.  This is usually implemented by
1901  *	the generic utility function @register_trigger() (see
1902  *	trace_event_triggers.c).
1903  *
1904  * @unreg: Removes the trigger from the list of triggers associated
1905  *	with the event, and disables the event trigger itself, after
1906  *	initializing it (via the event_trigger_ops @free() function).
1907  *	This is usually implemented by the generic utility function
1908  *	@unregister_trigger() (see trace_event_triggers.c).
1909  *
1910  * @unreg_all: An optional function called to remove all the triggers
1911  *	from the list of triggers associated with the event.  Called
1912  *	when a trigger file is opened in truncate mode.
1913  *
1914  * @set_filter: An optional function called to parse and set a filter
1915  *	for the trigger.  If no @set_filter() method is set for the
1916  *	event command, filters set by the user for the command will be
1917  *	ignored.  This is usually implemented by the generic utility
1918  *	function @set_trigger_filter() (see trace_event_triggers.c).
1919  *
1920  * @get_trigger_ops: The callback function invoked to retrieve the
1921  *	event_trigger_ops implementation associated with the command.
1922  *	This callback function allows a single event_command to
1923  *	support multiple trigger implementations via different sets of
1924  *	event_trigger_ops, depending on the value of the @param
1925  *	string.
1926  */
1927 struct event_command {
1928 	struct list_head	list;
1929 	char			*name;
1930 	enum event_trigger_type	trigger_type;
1931 	int			flags;
1932 	int			(*parse)(struct event_command *cmd_ops,
1933 					 struct trace_event_file *file,
1934 					 char *glob, char *cmd,
1935 					 char *param_and_filter);
1936 	int			(*reg)(char *glob,
1937 				       struct event_trigger_data *data,
1938 				       struct trace_event_file *file);
1939 	void			(*unreg)(char *glob,
1940 					 struct event_trigger_data *data,
1941 					 struct trace_event_file *file);
1942 	void			(*unreg_all)(struct trace_event_file *file);
1943 	int			(*set_filter)(char *filter_str,
1944 					      struct event_trigger_data *data,
1945 					      struct trace_event_file *file);
1946 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1947 };
1948 
1949 /**
1950  * enum event_command_flags - flags for struct event_command
1951  *
1952  * @POST_TRIGGER: A flag that says whether or not this command needs
1953  *	to have its action delayed until after the current event has
1954  *	been closed.  Some triggers need to avoid being invoked while
1955  *	an event is currently in the process of being logged, since
1956  *	the trigger may itself log data into the trace buffer.  Thus
1957  *	we make sure the current event is committed before invoking
1958  *	those triggers.  To do that, the trigger invocation is split
1959  *	in two - the first part checks the filter using the current
1960  *	trace record; if a command has the @post_trigger flag set, it
1961  *	sets a bit for itself in the return value, otherwise it
1962  *	directly invokes the trigger.  Once all commands have been
1963  *	either invoked or set their return flag, the current record is
1964  *	either committed or discarded.  At that point, if any commands
1965  *	have deferred their triggers, those commands are finally
1966  *	invoked following the close of the current event.  In other
1967  *	words, if the event_trigger_ops @func() probe implementation
1968  *	itself logs to the trace buffer, this flag should be set,
1969  *	otherwise it can be left unspecified.
1970  *
1971  * @NEEDS_REC: A flag that says whether or not this command needs
1972  *	access to the trace record in order to perform its function,
1973  *	regardless of whether or not it has a filter associated with
1974  *	it (filters make a trigger require access to the trace record
1975  *	but are not always present).
1976  */
1977 enum event_command_flags {
1978 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1979 	EVENT_CMD_FL_NEEDS_REC		= 2,
1980 };
1981 
event_command_post_trigger(struct event_command * cmd_ops)1982 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1983 {
1984 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1985 }
1986 
event_command_needs_rec(struct event_command * cmd_ops)1987 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1988 {
1989 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1990 }
1991 
1992 extern int trace_event_enable_disable(struct trace_event_file *file,
1993 				      int enable, int soft_disable);
1994 extern int tracing_alloc_snapshot(void);
1995 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1996 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1997 
1998 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1999 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2000 
2001 extern const char *__start___trace_bprintk_fmt[];
2002 extern const char *__stop___trace_bprintk_fmt[];
2003 
2004 extern const char *__start___tracepoint_str[];
2005 extern const char *__stop___tracepoint_str[];
2006 
2007 void trace_printk_control(bool enabled);
2008 void trace_printk_start_comm(void);
2009 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2010 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2011 
2012 /* Used from boot time tracer */
2013 extern int trace_set_options(struct trace_array *tr, char *option);
2014 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2015 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2016 					  unsigned long size, int cpu_id);
2017 extern int tracing_set_cpumask(struct trace_array *tr,
2018 				cpumask_var_t tracing_cpumask_new);
2019 
2020 
2021 #define MAX_EVENT_NAME_LEN	64
2022 
2023 extern ssize_t trace_parse_run_command(struct file *file,
2024 		const char __user *buffer, size_t count, loff_t *ppos,
2025 		int (*createfn)(const char *));
2026 
2027 extern unsigned int err_pos(char *cmd, const char *str);
2028 extern void tracing_log_err(struct trace_array *tr,
2029 			    const char *loc, const char *cmd,
2030 			    const char **errs, u8 type, u16 pos);
2031 
2032 /*
2033  * Normal trace_printk() and friends allocates special buffers
2034  * to do the manipulation, as well as saves the print formats
2035  * into sections to display. But the trace infrastructure wants
2036  * to use these without the added overhead at the price of being
2037  * a bit slower (used mainly for warnings, where we don't care
2038  * about performance). The internal_trace_puts() is for such
2039  * a purpose.
2040  */
2041 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2042 
2043 #undef FTRACE_ENTRY
2044 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2045 	extern struct trace_event_call					\
2046 	__aligned(4) event_##call;
2047 #undef FTRACE_ENTRY_DUP
2048 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2049 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2050 #undef FTRACE_ENTRY_PACKED
2051 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2052 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2053 
2054 #include "trace_entries.h"
2055 
2056 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2057 int perf_ftrace_event_register(struct trace_event_call *call,
2058 			       enum trace_reg type, void *data);
2059 #else
2060 #define perf_ftrace_event_register NULL
2061 #endif
2062 
2063 #ifdef CONFIG_FTRACE_SYSCALLS
2064 void init_ftrace_syscalls(void);
2065 const char *get_syscall_name(int syscall);
2066 #else
init_ftrace_syscalls(void)2067 static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)2068 static inline const char *get_syscall_name(int syscall)
2069 {
2070 	return NULL;
2071 }
2072 #endif
2073 
2074 #ifdef CONFIG_EVENT_TRACING
2075 void trace_event_init(void);
2076 void trace_event_eval_update(struct trace_eval_map **map, int len);
2077 /* Used from boot time tracer */
2078 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2079 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2080 #else
trace_event_init(void)2081 static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)2082 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2083 #endif
2084 
2085 #ifdef CONFIG_TRACER_SNAPSHOT
2086 void tracing_snapshot_instance(struct trace_array *tr);
2087 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2088 int tracing_arm_snapshot(struct trace_array *tr);
2089 void tracing_disarm_snapshot(struct trace_array *tr);
2090 #else
tracing_snapshot_instance(struct trace_array * tr)2091 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)2092 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2093 {
2094 	return 0;
2095 }
tracing_arm_snapshot(struct trace_array * tr)2096 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
tracing_disarm_snapshot(struct trace_array * tr)2097 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2098 #endif
2099 
2100 #ifdef CONFIG_PREEMPT_TRACER
2101 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2102 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2103 #else
tracer_preempt_on(unsigned long a0,unsigned long a1)2104 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)2105 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2106 #endif
2107 #ifdef CONFIG_IRQSOFF_TRACER
2108 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2109 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2110 #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)2111 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)2112 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2113 #endif
2114 
2115 /*
2116  * Reset the state of the trace_iterator so that it can read consumed data.
2117  * Normally, the trace_iterator is used for reading the data when it is not
2118  * consumed, and must retain state.
2119  */
trace_iterator_reset(struct trace_iterator * iter)2120 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2121 {
2122 	memset_startat(iter, 0, seq);
2123 	iter->pos = -1;
2124 }
2125 
2126 /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)2127 static inline bool __is_good_name(const char *name, bool hash_ok)
2128 {
2129 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2130 		return false;
2131 	while (*++name != '\0') {
2132 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2133 		    (!hash_ok || *name != '-'))
2134 			return false;
2135 	}
2136 	return true;
2137 }
2138 
2139 /* Check the name is good for event/group/fields */
is_good_name(const char * name)2140 static inline bool is_good_name(const char *name)
2141 {
2142 	return __is_good_name(name, false);
2143 }
2144 
2145 /* Check the name is good for system */
is_good_system_name(const char * name)2146 static inline bool is_good_system_name(const char *name)
2147 {
2148 	return __is_good_name(name, true);
2149 }
2150 
2151 /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)2152 static inline void sanitize_event_name(char *name)
2153 {
2154 	while (*name++ != '\0')
2155 		if (*name == ':' || *name == '.')
2156 			*name = '_';
2157 }
2158 
2159 /*
2160  * This is a generic way to read and write a u64 value from a file in tracefs.
2161  *
2162  * The value is stored on the variable pointed by *val. The value needs
2163  * to be at least *min and at most *max. The write is protected by an
2164  * existing *lock.
2165  */
2166 struct trace_min_max_param {
2167 	struct mutex	*lock;
2168 	u64		*val;
2169 	u64		*min;
2170 	u64		*max;
2171 };
2172 
2173 #define U64_STR_SIZE		24	/* 20 digits max */
2174 
2175 extern const struct file_operations trace_min_max_fops;
2176 
2177 #ifdef CONFIG_RV
2178 extern int rv_init_interface(void);
2179 #else
rv_init_interface(void)2180 static inline int rv_init_interface(void)
2181 {
2182 	return 0;
2183 }
2184 #endif
2185 
2186 /*
2187  * This is used only to distinguish
2188  * function address from trampoline code.
2189  * So this value has no meaning.
2190  */
2191 #define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2192 
2193 #endif /* _LINUX_KERNEL_TRACE_H */
2194