xref: /linux/kernel/trace/trace.h (revision 7c1badb2a9902ab4c5e9fe4093e532eeb11fd9fc)
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_MODULES
404 	struct list_head	mod_events;
405 #endif
406 #ifdef CONFIG_FUNCTION_TRACER
407 	struct ftrace_ops	*ops;
408 	struct trace_pid_list	__rcu *function_pids;
409 	struct trace_pid_list	__rcu *function_no_pids;
410 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
411 	struct fgraph_ops	*gops;
412 #endif
413 #ifdef CONFIG_DYNAMIC_FTRACE
414 	/* All of these are protected by the ftrace_lock */
415 	struct list_head	func_probes;
416 	struct list_head	mod_trace;
417 	struct list_head	mod_notrace;
418 #endif
419 	/* function tracing enabled */
420 	int			function_enabled;
421 #endif
422 	int			no_filter_buffering_ref;
423 	struct list_head	hist_vars;
424 #ifdef CONFIG_TRACER_SNAPSHOT
425 	struct cond_snapshot	*cond_snapshot;
426 #endif
427 	struct trace_func_repeats	__percpu *last_func_repeats;
428 	/*
429 	 * On boot up, the ring buffer is set to the minimum size, so that
430 	 * we do not waste memory on systems that are not using tracing.
431 	 */
432 	bool ring_buffer_expanded;
433 };
434 
435 enum {
436 	TRACE_ARRAY_FL_GLOBAL	= BIT(0),
437 	TRACE_ARRAY_FL_BOOT	= BIT(1),
438 	TRACE_ARRAY_FL_MOD_INIT	= BIT(2),
439 };
440 
441 #ifdef CONFIG_MODULES
442 bool module_exists(const char *module);
443 #else
module_exists(const char * module)444 static inline bool module_exists(const char *module)
445 {
446 	return false;
447 }
448 #endif
449 
450 extern struct list_head ftrace_trace_arrays;
451 
452 extern struct mutex trace_types_lock;
453 
454 extern int trace_array_get(struct trace_array *tr);
455 extern int tracing_check_open_get_tr(struct trace_array *tr);
456 extern struct trace_array *trace_array_find(const char *instance);
457 extern struct trace_array *trace_array_find_get(const char *instance);
458 
459 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
460 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
461 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
462 
463 extern bool trace_clock_in_ns(struct trace_array *tr);
464 
465 /*
466  * The global tracer (top) should be the first trace array added,
467  * but we check the flag anyway.
468  */
top_trace_array(void)469 static inline struct trace_array *top_trace_array(void)
470 {
471 	struct trace_array *tr;
472 
473 	if (list_empty(&ftrace_trace_arrays))
474 		return NULL;
475 
476 	tr = list_entry(ftrace_trace_arrays.prev,
477 			typeof(*tr), list);
478 	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
479 	return tr;
480 }
481 
482 #define FTRACE_CMP_TYPE(var, type) \
483 	__builtin_types_compatible_p(typeof(var), type *)
484 
485 #undef IF_ASSIGN
486 #define IF_ASSIGN(var, entry, etype, id)			\
487 	if (FTRACE_CMP_TYPE(var, etype)) {			\
488 		var = (typeof(var))(entry);			\
489 		WARN_ON(id != 0 && (entry)->type != id);	\
490 		break;						\
491 	}
492 
493 /* Will cause compile errors if type is not found. */
494 extern void __ftrace_bad_type(void);
495 
496 /*
497  * The trace_assign_type is a verifier that the entry type is
498  * the same as the type being assigned. To add new types simply
499  * add a line with the following format:
500  *
501  * IF_ASSIGN(var, ent, type, id);
502  *
503  *  Where "type" is the trace type that includes the trace_entry
504  *  as the "ent" item. And "id" is the trace identifier that is
505  *  used in the trace_type enum.
506  *
507  *  If the type can have more than one id, then use zero.
508  */
509 #define trace_assign_type(var, ent)					\
510 	do {								\
511 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
512 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
513 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
514 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
515 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
516 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
517 		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
518 		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
519 		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
520 		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
521 		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
522 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
523 			  TRACE_MMIO_RW);				\
524 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
525 			  TRACE_MMIO_MAP);				\
526 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
527 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
528 			  TRACE_GRAPH_ENT);		\
529 		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
530 			  TRACE_GRAPH_RETADDR_ENT);		\
531 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
532 			  TRACE_GRAPH_RET);		\
533 		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
534 			  TRACE_FUNC_REPEATS);				\
535 		__ftrace_bad_type();					\
536 	} while (0)
537 
538 /*
539  * An option specific to a tracer. This is a boolean value.
540  * The bit is the bit index that sets its value on the
541  * flags value in struct tracer_flags.
542  */
543 struct tracer_opt {
544 	const char	*name; /* Will appear on the trace_options file */
545 	u32		bit; /* Mask assigned in val field in tracer_flags */
546 };
547 
548 /*
549  * The set of specific options for a tracer. Your tracer
550  * have to set the initial value of the flags val.
551  */
552 struct tracer_flags {
553 	u32			val;
554 	struct tracer_opt	*opts;
555 	struct tracer		*trace;
556 };
557 
558 /* Makes more easy to define a tracer opt */
559 #define TRACER_OPT(s, b)	.name = #s, .bit = b
560 
561 
562 struct trace_option_dentry {
563 	struct tracer_opt		*opt;
564 	struct tracer_flags		*flags;
565 	struct trace_array		*tr;
566 	struct dentry			*entry;
567 };
568 
569 /**
570  * struct tracer - a specific tracer and its callbacks to interact with tracefs
571  * @name: the name chosen to select it on the available_tracers file
572  * @init: called when one switches to this tracer (echo name > current_tracer)
573  * @reset: called when one switches to another tracer
574  * @start: called when tracing is unpaused (echo 1 > tracing_on)
575  * @stop: called when tracing is paused (echo 0 > tracing_on)
576  * @update_thresh: called when tracing_thresh is updated
577  * @open: called when the trace file is opened
578  * @pipe_open: called when the trace_pipe file is opened
579  * @close: called when the trace file is released
580  * @pipe_close: called when the trace_pipe file is released
581  * @read: override the default read callback on trace_pipe
582  * @splice_read: override the default splice_read callback on trace_pipe
583  * @selftest: selftest to run on boot (see trace_selftest.c)
584  * @print_headers: override the first lines that describe your columns
585  * @print_line: callback that prints a trace
586  * @set_flag: signals one of your private flags changed (trace_options file)
587  * @flags: your private flags
588  */
589 struct tracer {
590 	const char		*name;
591 	int			(*init)(struct trace_array *tr);
592 	void			(*reset)(struct trace_array *tr);
593 	void			(*start)(struct trace_array *tr);
594 	void			(*stop)(struct trace_array *tr);
595 	int			(*update_thresh)(struct trace_array *tr);
596 	void			(*open)(struct trace_iterator *iter);
597 	void			(*pipe_open)(struct trace_iterator *iter);
598 	void			(*close)(struct trace_iterator *iter);
599 	void			(*pipe_close)(struct trace_iterator *iter);
600 	ssize_t			(*read)(struct trace_iterator *iter,
601 					struct file *filp, char __user *ubuf,
602 					size_t cnt, loff_t *ppos);
603 	ssize_t			(*splice_read)(struct trace_iterator *iter,
604 					       struct file *filp,
605 					       loff_t *ppos,
606 					       struct pipe_inode_info *pipe,
607 					       size_t len,
608 					       unsigned int flags);
609 #ifdef CONFIG_FTRACE_STARTUP_TEST
610 	int			(*selftest)(struct tracer *trace,
611 					    struct trace_array *tr);
612 #endif
613 	void			(*print_header)(struct seq_file *m);
614 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
615 	/* If you handled the flag setting, return 0 */
616 	int			(*set_flag)(struct trace_array *tr,
617 					    u32 old_flags, u32 bit, int set);
618 	/* Return 0 if OK with change, else return non-zero */
619 	int			(*flag_changed)(struct trace_array *tr,
620 						u32 mask, int set);
621 	struct tracer		*next;
622 	struct tracer_flags	*flags;
623 	int			enabled;
624 	bool			print_max;
625 	bool			allow_instances;
626 #ifdef CONFIG_TRACER_MAX_TRACE
627 	bool			use_max_tr;
628 #endif
629 	/* True if tracer cannot be enabled in kernel param */
630 	bool			noboot;
631 };
632 
633 static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)634 trace_buffer_iter(struct trace_iterator *iter, int cpu)
635 {
636 	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
637 }
638 
639 int tracer_init(struct tracer *t, struct trace_array *tr);
640 int tracing_is_enabled(void);
641 void tracing_reset_online_cpus(struct array_buffer *buf);
642 void tracing_reset_all_online_cpus(void);
643 void tracing_reset_all_online_cpus_unlocked(void);
644 int tracing_open_generic(struct inode *inode, struct file *filp);
645 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
646 int tracing_release_generic_tr(struct inode *inode, struct file *file);
647 int tracing_open_file_tr(struct inode *inode, struct file *filp);
648 int tracing_release_file_tr(struct inode *inode, struct file *filp);
649 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
650 bool tracing_is_disabled(void);
651 bool tracer_tracing_is_on(struct trace_array *tr);
652 void tracer_tracing_on(struct trace_array *tr);
653 void tracer_tracing_off(struct trace_array *tr);
654 struct dentry *trace_create_file(const char *name,
655 				 umode_t mode,
656 				 struct dentry *parent,
657 				 void *data,
658 				 const struct file_operations *fops);
659 
660 int tracing_init_dentry(void);
661 
662 struct ring_buffer_event;
663 
664 struct ring_buffer_event *
665 trace_buffer_lock_reserve(struct trace_buffer *buffer,
666 			  int type,
667 			  unsigned long len,
668 			  unsigned int trace_ctx);
669 
670 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
671 
672 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
673 						struct trace_array_cpu *data);
674 
675 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
676 					  int *ent_cpu, u64 *ent_ts);
677 
678 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
679 					struct ring_buffer_event *event);
680 
681 bool trace_is_tracepoint_string(const char *str);
682 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
683 char *trace_iter_expand_format(struct trace_iterator *iter);
684 bool ignore_event(struct trace_iterator *iter);
685 
686 int trace_empty(struct trace_iterator *iter);
687 
688 void *trace_find_next_entry_inc(struct trace_iterator *iter);
689 
690 void trace_init_global_iter(struct trace_iterator *iter);
691 
692 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
693 
694 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
695 unsigned long trace_total_entries(struct trace_array *tr);
696 
697 void trace_function(struct trace_array *tr,
698 		    unsigned long ip,
699 		    unsigned long parent_ip,
700 		    unsigned int trace_ctx);
701 void trace_graph_function(struct trace_array *tr,
702 		    unsigned long ip,
703 		    unsigned long parent_ip,
704 		    unsigned int trace_ctx);
705 void trace_latency_header(struct seq_file *m);
706 void trace_default_header(struct seq_file *m);
707 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
708 
709 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
710 			struct ftrace_regs *fregs);
711 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
712 		      struct ftrace_regs *fregs);
713 
714 void tracing_start_cmdline_record(void);
715 void tracing_stop_cmdline_record(void);
716 void tracing_start_tgid_record(void);
717 void tracing_stop_tgid_record(void);
718 
719 int register_tracer(struct tracer *type);
720 int is_tracing_stopped(void);
721 
722 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
723 
724 extern cpumask_var_t __read_mostly tracing_buffer_mask;
725 
726 #define for_each_tracing_cpu(cpu)	\
727 	for_each_cpu(cpu, tracing_buffer_mask)
728 
729 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
730 
731 extern unsigned long tracing_thresh;
732 
733 /* PID filtering */
734 
735 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
736 			     pid_t search_pid);
737 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
738 			    struct trace_pid_list *filtered_no_pids,
739 			    struct task_struct *task);
740 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
741 				  struct task_struct *self,
742 				  struct task_struct *task);
743 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
744 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
745 int trace_pid_show(struct seq_file *m, void *v);
746 int trace_pid_write(struct trace_pid_list *filtered_pids,
747 		    struct trace_pid_list **new_pid_list,
748 		    const char __user *ubuf, size_t cnt);
749 
750 #ifdef CONFIG_TRACER_MAX_TRACE
751 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
752 		   void *cond_data);
753 void update_max_tr_single(struct trace_array *tr,
754 			  struct task_struct *tsk, int cpu);
755 
756 #ifdef CONFIG_FSNOTIFY
757 #define LATENCY_FS_NOTIFY
758 #endif
759 #endif /* CONFIG_TRACER_MAX_TRACE */
760 
761 #ifdef LATENCY_FS_NOTIFY
762 void latency_fsnotify(struct trace_array *tr);
763 #else
latency_fsnotify(struct trace_array * tr)764 static inline void latency_fsnotify(struct trace_array *tr) { }
765 #endif
766 
767 #ifdef CONFIG_STACKTRACE
768 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
769 #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)770 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
771 				 int skip)
772 {
773 }
774 #endif /* CONFIG_STACKTRACE */
775 
776 void trace_last_func_repeats(struct trace_array *tr,
777 			     struct trace_func_repeats *last_info,
778 			     unsigned int trace_ctx);
779 
780 extern u64 ftrace_now(int cpu);
781 
782 extern void trace_find_cmdline(int pid, char comm[]);
783 extern int trace_find_tgid(int pid);
784 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
785 
786 #ifdef CONFIG_DYNAMIC_FTRACE
787 extern unsigned long ftrace_update_tot_cnt;
788 extern unsigned long ftrace_number_of_pages;
789 extern unsigned long ftrace_number_of_groups;
790 extern u64 ftrace_update_time;
791 extern u64 ftrace_total_mod_time;
792 void ftrace_init_trace_array(struct trace_array *tr);
793 #else
ftrace_init_trace_array(struct trace_array * tr)794 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
795 #endif
796 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
797 extern int DYN_FTRACE_TEST_NAME(void);
798 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
799 extern int DYN_FTRACE_TEST_NAME2(void);
800 
801 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
802 extern bool tracing_selftest_disabled;
803 
804 #ifdef CONFIG_FTRACE_STARTUP_TEST
805 extern void __init disable_tracing_selftest(const char *reason);
806 
807 extern int trace_selftest_startup_function(struct tracer *trace,
808 					   struct trace_array *tr);
809 extern int trace_selftest_startup_function_graph(struct tracer *trace,
810 						 struct trace_array *tr);
811 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
812 					  struct trace_array *tr);
813 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
814 					     struct trace_array *tr);
815 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
816 						 struct trace_array *tr);
817 extern int trace_selftest_startup_wakeup(struct tracer *trace,
818 					 struct trace_array *tr);
819 extern int trace_selftest_startup_nop(struct tracer *trace,
820 					 struct trace_array *tr);
821 extern int trace_selftest_startup_branch(struct tracer *trace,
822 					 struct trace_array *tr);
823 /*
824  * Tracer data references selftest functions that only occur
825  * on boot up. These can be __init functions. Thus, when selftests
826  * are enabled, then the tracers need to reference __init functions.
827  */
828 #define __tracer_data		__refdata
829 #else
disable_tracing_selftest(const char * reason)830 static inline void __init disable_tracing_selftest(const char *reason)
831 {
832 }
833 /* Tracers are seldom changed. Optimize when selftests are disabled. */
834 #define __tracer_data		__read_mostly
835 #endif /* CONFIG_FTRACE_STARTUP_TEST */
836 
837 extern void *head_page(struct trace_array_cpu *data);
838 extern unsigned long long ns2usecs(u64 nsec);
839 extern int
840 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
841 extern int
842 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
843 extern int
844 trace_array_vprintk(struct trace_array *tr,
845 		    unsigned long ip, const char *fmt, va_list args);
846 int trace_array_printk_buf(struct trace_buffer *buffer,
847 			   unsigned long ip, const char *fmt, ...);
848 void trace_printk_seq(struct trace_seq *s);
849 enum print_line_t print_trace_line(struct trace_iterator *iter);
850 
851 extern char trace_find_mark(unsigned long long duration);
852 
853 struct ftrace_hash;
854 
855 struct ftrace_mod_load {
856 	struct list_head	list;
857 	char			*func;
858 	char			*module;
859 	int			 enable;
860 };
861 
862 enum {
863 	FTRACE_HASH_FL_MOD	= (1 << 0),
864 };
865 
866 struct ftrace_hash {
867 	unsigned long		size_bits;
868 	struct hlist_head	*buckets;
869 	unsigned long		count;
870 	unsigned long		flags;
871 	struct rcu_head		rcu;
872 };
873 
874 struct ftrace_func_entry *
875 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
876 
ftrace_hash_empty(struct ftrace_hash * hash)877 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
878 {
879 	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
880 }
881 
882 /* Standard output formatting function used for function return traces */
883 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
884 
885 /* Flag options */
886 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
887 #define TRACE_GRAPH_PRINT_CPU           0x2
888 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
889 #define TRACE_GRAPH_PRINT_PROC          0x8
890 #define TRACE_GRAPH_PRINT_DURATION      0x10
891 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
892 #define TRACE_GRAPH_PRINT_REL_TIME      0x40
893 #define TRACE_GRAPH_PRINT_IRQS          0x80
894 #define TRACE_GRAPH_PRINT_TAIL          0x100
895 #define TRACE_GRAPH_SLEEP_TIME          0x200
896 #define TRACE_GRAPH_GRAPH_TIME          0x400
897 #define TRACE_GRAPH_PRINT_RETVAL        0x800
898 #define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
899 #define TRACE_GRAPH_PRINT_RETADDR       0x2000
900 #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
901 #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
902 
903 extern void ftrace_graph_sleep_time_control(bool enable);
904 
905 #ifdef CONFIG_FUNCTION_PROFILER
906 extern void ftrace_graph_graph_time_control(bool enable);
907 #else
ftrace_graph_graph_time_control(bool enable)908 static inline void ftrace_graph_graph_time_control(bool enable) { }
909 #endif
910 
911 extern enum print_line_t
912 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
913 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
914 extern void
915 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
916 extern void graph_trace_open(struct trace_iterator *iter);
917 extern void graph_trace_close(struct trace_iterator *iter);
918 extern int __trace_graph_entry(struct trace_array *tr,
919 			       struct ftrace_graph_ent *trace,
920 			       unsigned int trace_ctx);
921 extern int __trace_graph_retaddr_entry(struct trace_array *tr,
922 				struct ftrace_graph_ent *trace,
923 				unsigned int trace_ctx,
924 				unsigned long retaddr);
925 extern void __trace_graph_return(struct trace_array *tr,
926 				 struct ftrace_graph_ret *trace,
927 				 unsigned int trace_ctx,
928 				 u64 calltime, u64 rettime);
929 
930 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
931 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
932 extern void free_fgraph_ops(struct trace_array *tr);
933 
934 enum {
935 	TRACE_GRAPH_FL		= 1,
936 
937 	/*
938 	 * In the very unlikely case that an interrupt came in
939 	 * at a start of graph tracing, and we want to trace
940 	 * the function in that interrupt, the depth can be greater
941 	 * than zero, because of the preempted start of a previous
942 	 * trace. In an even more unlikely case, depth could be 2
943 	 * if a softirq interrupted the start of graph tracing,
944 	 * followed by an interrupt preempting a start of graph
945 	 * tracing in the softirq, and depth can even be 3
946 	 * if an NMI came in at the start of an interrupt function
947 	 * that preempted a softirq start of a function that
948 	 * preempted normal context!!!! Luckily, it can't be
949 	 * greater than 3, so the next two bits are a mask
950 	 * of what the depth is when we set TRACE_GRAPH_FL
951 	 */
952 
953 	TRACE_GRAPH_DEPTH_START_BIT,
954 	TRACE_GRAPH_DEPTH_END_BIT,
955 
956 	/*
957 	 * To implement set_graph_notrace, if this bit is set, we ignore
958 	 * function graph tracing of called functions, until the return
959 	 * function is called to clear it.
960 	 */
961 	TRACE_GRAPH_NOTRACE_BIT,
962 };
963 
964 #define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
965 
ftrace_graph_depth(unsigned long * task_var)966 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
967 {
968 	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
969 }
970 
ftrace_graph_set_depth(unsigned long * task_var,int depth)971 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
972 {
973 	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
974 	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
975 }
976 
977 #ifdef CONFIG_DYNAMIC_FTRACE
978 extern struct ftrace_hash __rcu *ftrace_graph_hash;
979 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
980 
981 static inline int
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)982 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
983 {
984 	unsigned long addr = trace->func;
985 	int ret = 0;
986 	struct ftrace_hash *hash;
987 
988 	preempt_disable_notrace();
989 
990 	/*
991 	 * Have to open code "rcu_dereference_sched()" because the
992 	 * function graph tracer can be called when RCU is not
993 	 * "watching".
994 	 * Protected with schedule_on_each_cpu(ftrace_sync)
995 	 */
996 	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
997 
998 	if (ftrace_hash_empty(hash)) {
999 		ret = 1;
1000 		goto out;
1001 	}
1002 
1003 	if (ftrace_lookup_ip(hash, addr)) {
1004 		/*
1005 		 * This needs to be cleared on the return functions
1006 		 * when the depth is zero.
1007 		 */
1008 		*task_var |= TRACE_GRAPH_FL;
1009 		ftrace_graph_set_depth(task_var, trace->depth);
1010 
1011 		/*
1012 		 * If no irqs are to be traced, but a set_graph_function
1013 		 * is set, and called by an interrupt handler, we still
1014 		 * want to trace it.
1015 		 */
1016 		if (in_hardirq())
1017 			trace_recursion_set(TRACE_IRQ_BIT);
1018 		else
1019 			trace_recursion_clear(TRACE_IRQ_BIT);
1020 		ret = 1;
1021 	}
1022 
1023 out:
1024 	preempt_enable_notrace();
1025 	return ret;
1026 }
1027 
1028 static inline void
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1029 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1030 {
1031 	unsigned long *task_var = fgraph_get_task_var(gops);
1032 
1033 	if ((*task_var & TRACE_GRAPH_FL) &&
1034 	    trace->depth == ftrace_graph_depth(task_var))
1035 		*task_var &= ~TRACE_GRAPH_FL;
1036 }
1037 
ftrace_graph_notrace_addr(unsigned long addr)1038 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1039 {
1040 	int ret = 0;
1041 	struct ftrace_hash *notrace_hash;
1042 
1043 	preempt_disable_notrace();
1044 
1045 	/*
1046 	 * Have to open code "rcu_dereference_sched()" because the
1047 	 * function graph tracer can be called when RCU is not
1048 	 * "watching".
1049 	 * Protected with schedule_on_each_cpu(ftrace_sync)
1050 	 */
1051 	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1052 						 !preemptible());
1053 
1054 	if (ftrace_lookup_ip(notrace_hash, addr))
1055 		ret = 1;
1056 
1057 	preempt_enable_notrace();
1058 	return ret;
1059 }
1060 #else
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)1061 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1062 {
1063 	return 1;
1064 }
1065 
ftrace_graph_notrace_addr(unsigned long addr)1066 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1067 {
1068 	return 0;
1069 }
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1070 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1071 { }
1072 #endif /* CONFIG_DYNAMIC_FTRACE */
1073 
1074 extern unsigned int fgraph_max_depth;
1075 extern bool fgraph_sleep_time;
1076 
1077 static inline bool
ftrace_graph_ignore_func(struct fgraph_ops * gops,struct ftrace_graph_ent * trace)1078 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1079 {
1080 	unsigned long *task_var = fgraph_get_task_var(gops);
1081 
1082 	/* trace it when it is-nested-in or is a function enabled. */
1083 	return !((*task_var & TRACE_GRAPH_FL) ||
1084 		 ftrace_graph_addr(task_var, trace)) ||
1085 		(trace->depth < 0) ||
1086 		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1087 }
1088 
1089 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1090 		     struct ftrace_ops *src_ops);
1091 
1092 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1093 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)1094 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1095 {
1096 	return TRACE_TYPE_UNHANDLED;
1097 }
free_fgraph_ops(struct trace_array * tr)1098 static inline void free_fgraph_ops(struct trace_array *tr) { }
1099 /* ftrace_ops may not be defined */
1100 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1101 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1102 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1103 
1104 extern struct list_head ftrace_pids;
1105 
1106 #ifdef CONFIG_FUNCTION_TRACER
1107 
1108 #define FTRACE_PID_IGNORE	-1
1109 #define FTRACE_PID_TRACE	-2
1110 
1111 struct ftrace_func_command {
1112 	struct list_head	list;
1113 	char			*name;
1114 	int			(*func)(struct trace_array *tr,
1115 					struct ftrace_hash *hash,
1116 					char *func, char *cmd,
1117 					char *params, int enable);
1118 };
1119 extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)1120 static inline int ftrace_trace_task(struct trace_array *tr)
1121 {
1122 	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1123 		FTRACE_PID_IGNORE;
1124 }
1125 extern int ftrace_is_dead(void);
1126 int ftrace_create_function_files(struct trace_array *tr,
1127 				 struct dentry *parent);
1128 void ftrace_destroy_function_files(struct trace_array *tr);
1129 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1130 void ftrace_free_ftrace_ops(struct trace_array *tr);
1131 void ftrace_init_global_array_ops(struct trace_array *tr);
1132 struct trace_array *trace_get_global_array(void);
1133 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1134 void ftrace_reset_array_ops(struct trace_array *tr);
1135 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1136 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1137 				  struct dentry *d_tracer);
1138 void ftrace_clear_pids(struct trace_array *tr);
1139 int init_function_trace(void);
1140 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1141 #else
ftrace_trace_task(struct trace_array * tr)1142 static inline int ftrace_trace_task(struct trace_array *tr)
1143 {
1144 	return 1;
1145 }
ftrace_is_dead(void)1146 static inline int ftrace_is_dead(void) { return 0; }
1147 static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1148 ftrace_create_function_files(struct trace_array *tr,
1149 			     struct dentry *parent)
1150 {
1151 	return 0;
1152 }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1153 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1154 {
1155 	return 0;
1156 }
ftrace_free_ftrace_ops(struct trace_array * tr)1157 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1158 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1159 static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1160 ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1161 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1162 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1163 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1164 static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1165 static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1166 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1167 /* ftace_func_t type is not defined, use macro instead of static inline */
1168 #define ftrace_init_array_ops(tr, func) do { } while (0)
1169 #endif /* CONFIG_FUNCTION_TRACER */
1170 
1171 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1172 
1173 struct ftrace_probe_ops {
1174 	void			(*func)(unsigned long ip,
1175 					unsigned long parent_ip,
1176 					struct trace_array *tr,
1177 					struct ftrace_probe_ops *ops,
1178 					void *data);
1179 	int			(*init)(struct ftrace_probe_ops *ops,
1180 					struct trace_array *tr,
1181 					unsigned long ip, void *init_data,
1182 					void **data);
1183 	void			(*free)(struct ftrace_probe_ops *ops,
1184 					struct trace_array *tr,
1185 					unsigned long ip, void *data);
1186 	int			(*print)(struct seq_file *m,
1187 					 unsigned long ip,
1188 					 struct ftrace_probe_ops *ops,
1189 					 void *data);
1190 };
1191 
1192 struct ftrace_func_mapper;
1193 typedef int (*ftrace_mapper_func)(void *data);
1194 
1195 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1196 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1197 					   unsigned long ip);
1198 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1199 			       unsigned long ip, void *data);
1200 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1201 				   unsigned long ip);
1202 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1203 			     ftrace_mapper_func free_func);
1204 
1205 extern int
1206 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1207 			       struct ftrace_probe_ops *ops, void *data);
1208 extern int
1209 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1210 				      struct ftrace_probe_ops *ops);
1211 extern void clear_ftrace_function_probes(struct trace_array *tr);
1212 
1213 int register_ftrace_command(struct ftrace_func_command *cmd);
1214 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1215 
1216 void ftrace_create_filter_files(struct ftrace_ops *ops,
1217 				struct dentry *parent);
1218 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1219 
1220 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1221 			     int len, int reset);
1222 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1223 			      int len, int reset);
1224 #else
1225 struct ftrace_func_command;
1226 
register_ftrace_command(struct ftrace_func_command * cmd)1227 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1228 {
1229 	return -EINVAL;
1230 }
unregister_ftrace_command(char * cmd_name)1231 static inline __init int unregister_ftrace_command(char *cmd_name)
1232 {
1233 	return -EINVAL;
1234 }
clear_ftrace_function_probes(struct trace_array * tr)1235 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1236 {
1237 }
1238 
1239 /*
1240  * The ops parameter passed in is usually undefined.
1241  * This must be a macro.
1242  */
1243 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1244 #define ftrace_destroy_filter_files(ops) do { } while (0)
1245 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1246 
1247 bool ftrace_event_is_function(struct trace_event_call *call);
1248 
1249 /*
1250  * struct trace_parser - servers for reading the user input separated by spaces
1251  * @cont: set if the input is not complete - no final space char was found
1252  * @buffer: holds the parsed user input
1253  * @idx: user input length
1254  * @size: buffer size
1255  */
1256 struct trace_parser {
1257 	bool		cont;
1258 	char		*buffer;
1259 	unsigned	idx;
1260 	unsigned	size;
1261 };
1262 
trace_parser_loaded(struct trace_parser * parser)1263 static inline bool trace_parser_loaded(struct trace_parser *parser)
1264 {
1265 	return (parser->idx != 0);
1266 }
1267 
trace_parser_cont(struct trace_parser * parser)1268 static inline bool trace_parser_cont(struct trace_parser *parser)
1269 {
1270 	return parser->cont;
1271 }
1272 
trace_parser_clear(struct trace_parser * parser)1273 static inline void trace_parser_clear(struct trace_parser *parser)
1274 {
1275 	parser->cont = false;
1276 	parser->idx = 0;
1277 }
1278 
1279 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1280 extern void trace_parser_put(struct trace_parser *parser);
1281 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1282 	size_t cnt, loff_t *ppos);
1283 
1284 /*
1285  * Only create function graph options if function graph is configured.
1286  */
1287 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1288 # define FGRAPH_FLAGS						\
1289 		C(DISPLAY_GRAPH,	"display-graph"),
1290 #else
1291 # define FGRAPH_FLAGS
1292 #endif
1293 
1294 #ifdef CONFIG_BRANCH_TRACER
1295 # define BRANCH_FLAGS					\
1296 		C(BRANCH,		"branch"),
1297 #else
1298 # define BRANCH_FLAGS
1299 #endif
1300 
1301 #ifdef CONFIG_FUNCTION_TRACER
1302 # define FUNCTION_FLAGS						\
1303 		C(FUNCTION,		"function-trace"),	\
1304 		C(FUNC_FORK,		"function-fork"),
1305 # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
1306 #else
1307 # define FUNCTION_FLAGS
1308 # define FUNCTION_DEFAULT_FLAGS		0UL
1309 # define TRACE_ITER_FUNC_FORK		0UL
1310 #endif
1311 
1312 #ifdef CONFIG_STACKTRACE
1313 # define STACK_FLAGS				\
1314 		C(STACKTRACE,		"stacktrace"),
1315 #else
1316 # define STACK_FLAGS
1317 #endif
1318 
1319 /*
1320  * trace_iterator_flags is an enumeration that defines bit
1321  * positions into trace_flags that controls the output.
1322  *
1323  * NOTE: These bits must match the trace_options array in
1324  *       trace.c (this macro guarantees it).
1325  */
1326 #define TRACE_FLAGS						\
1327 		C(PRINT_PARENT,		"print-parent"),	\
1328 		C(SYM_OFFSET,		"sym-offset"),		\
1329 		C(SYM_ADDR,		"sym-addr"),		\
1330 		C(VERBOSE,		"verbose"),		\
1331 		C(RAW,			"raw"),			\
1332 		C(HEX,			"hex"),			\
1333 		C(BIN,			"bin"),			\
1334 		C(BLOCK,		"block"),		\
1335 		C(FIELDS,		"fields"),		\
1336 		C(PRINTK,		"trace_printk"),	\
1337 		C(ANNOTATE,		"annotate"),		\
1338 		C(USERSTACKTRACE,	"userstacktrace"),	\
1339 		C(SYM_USEROBJ,		"sym-userobj"),		\
1340 		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1341 		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1342 		C(LATENCY_FMT,		"latency-format"),	\
1343 		C(RECORD_CMD,		"record-cmd"),		\
1344 		C(RECORD_TGID,		"record-tgid"),		\
1345 		C(OVERWRITE,		"overwrite"),		\
1346 		C(STOP_ON_FREE,		"disable_on_free"),	\
1347 		C(IRQ_INFO,		"irq-info"),		\
1348 		C(MARKERS,		"markers"),		\
1349 		C(EVENT_FORK,		"event-fork"),		\
1350 		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1351 		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1352 		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1353 		FUNCTION_FLAGS					\
1354 		FGRAPH_FLAGS					\
1355 		STACK_FLAGS					\
1356 		BRANCH_FLAGS
1357 
1358 /*
1359  * By defining C, we can make TRACE_FLAGS a list of bit names
1360  * that will define the bits for the flag masks.
1361  */
1362 #undef C
1363 #define C(a, b) TRACE_ITER_##a##_BIT
1364 
1365 enum trace_iterator_bits {
1366 	TRACE_FLAGS
1367 	/* Make sure we don't go more than we have bits for */
1368 	TRACE_ITER_LAST_BIT
1369 };
1370 
1371 /*
1372  * By redefining C, we can make TRACE_FLAGS a list of masks that
1373  * use the bits as defined above.
1374  */
1375 #undef C
1376 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1377 
1378 enum trace_iterator_flags { TRACE_FLAGS };
1379 
1380 /*
1381  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1382  * control the output of kernel symbols.
1383  */
1384 #define TRACE_ITER_SYM_MASK \
1385 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1386 
1387 extern struct tracer nop_trace;
1388 
1389 #ifdef CONFIG_BRANCH_TRACER
1390 extern int enable_branch_tracing(struct trace_array *tr);
1391 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1392 static inline int trace_branch_enable(struct trace_array *tr)
1393 {
1394 	if (tr->trace_flags & TRACE_ITER_BRANCH)
1395 		return enable_branch_tracing(tr);
1396 	return 0;
1397 }
trace_branch_disable(void)1398 static inline void trace_branch_disable(void)
1399 {
1400 	/* due to races, always disable */
1401 	disable_branch_tracing();
1402 }
1403 #else
trace_branch_enable(struct trace_array * tr)1404 static inline int trace_branch_enable(struct trace_array *tr)
1405 {
1406 	return 0;
1407 }
trace_branch_disable(void)1408 static inline void trace_branch_disable(void)
1409 {
1410 }
1411 #endif /* CONFIG_BRANCH_TRACER */
1412 
1413 /* set ring buffers to default size if not already done so */
1414 int tracing_update_buffers(struct trace_array *tr);
1415 
1416 union trace_synth_field {
1417 	u8				as_u8;
1418 	u16				as_u16;
1419 	u32				as_u32;
1420 	u64				as_u64;
1421 	struct trace_dynamic_info	as_dynamic;
1422 };
1423 
1424 struct ftrace_event_field {
1425 	struct list_head	link;
1426 	const char		*name;
1427 	const char		*type;
1428 	int			filter_type;
1429 	int			offset;
1430 	int			size;
1431 	unsigned int		is_signed:1;
1432 	unsigned int		needs_test:1;
1433 	int			len;
1434 };
1435 
1436 struct prog_entry;
1437 
1438 struct event_filter {
1439 	struct prog_entry __rcu	*prog;
1440 	char			*filter_string;
1441 };
1442 
1443 struct event_subsystem {
1444 	struct list_head	list;
1445 	const char		*name;
1446 	struct event_filter	*filter;
1447 	int			ref_count;
1448 };
1449 
1450 struct trace_subsystem_dir {
1451 	struct list_head		list;
1452 	struct event_subsystem		*subsystem;
1453 	struct trace_array		*tr;
1454 	struct eventfs_inode		*ei;
1455 	int				ref_count;
1456 	int				nr_events;
1457 };
1458 
1459 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1460 				     struct trace_buffer *buffer,
1461 				     struct ring_buffer_event *event,
1462 				     unsigned int trcace_ctx,
1463 				     struct pt_regs *regs);
1464 
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1465 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1466 					      struct trace_buffer *buffer,
1467 					      struct ring_buffer_event *event,
1468 					      unsigned int trace_ctx)
1469 {
1470 	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1471 }
1472 
1473 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1474 int trace_save_cmdline(struct task_struct *tsk);
1475 int trace_create_savedcmd(void);
1476 int trace_alloc_tgid_map(void);
1477 void trace_free_saved_cmdlines_buffer(void);
1478 
1479 extern const struct file_operations tracing_saved_cmdlines_fops;
1480 extern const struct file_operations tracing_saved_tgids_fops;
1481 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1482 
1483 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1484 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1485 void trace_buffered_event_disable(void);
1486 void trace_buffered_event_enable(void);
1487 
1488 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1489 
1490 static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1491 __trace_event_discard_commit(struct trace_buffer *buffer,
1492 			     struct ring_buffer_event *event)
1493 {
1494 	if (this_cpu_read(trace_buffered_event) == event) {
1495 		/* Simply release the temp buffer and enable preemption */
1496 		this_cpu_dec(trace_buffered_event_cnt);
1497 		preempt_enable_notrace();
1498 		return;
1499 	}
1500 	/* ring_buffer_discard_commit() enables preemption */
1501 	ring_buffer_discard_commit(buffer, event);
1502 }
1503 
1504 /*
1505  * Helper function for event_trigger_unlock_commit{_regs}().
1506  * If there are event triggers attached to this event that requires
1507  * filtering against its fields, then they will be called as the
1508  * entry already holds the field information of the current event.
1509  *
1510  * It also checks if the event should be discarded or not.
1511  * It is to be discarded if the event is soft disabled and the
1512  * event was only recorded to process triggers, or if the event
1513  * filter is active and this event did not match the filters.
1514  *
1515  * Returns true if the event is discarded, false otherwise.
1516  */
1517 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)1518 __event_trigger_test_discard(struct trace_event_file *file,
1519 			     struct trace_buffer *buffer,
1520 			     struct ring_buffer_event *event,
1521 			     void *entry,
1522 			     enum event_trigger_type *tt)
1523 {
1524 	unsigned long eflags = file->flags;
1525 
1526 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1527 		*tt = event_triggers_call(file, buffer, entry, event);
1528 
1529 	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1530 				    EVENT_FILE_FL_FILTERED |
1531 				    EVENT_FILE_FL_PID_FILTER))))
1532 		return false;
1533 
1534 	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1535 		goto discard;
1536 
1537 	if (file->flags & EVENT_FILE_FL_FILTERED &&
1538 	    !filter_match_preds(file->filter, entry))
1539 		goto discard;
1540 
1541 	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1542 	    trace_event_ignore_this_pid(file))
1543 		goto discard;
1544 
1545 	return false;
1546  discard:
1547 	__trace_event_discard_commit(buffer, event);
1548 	return true;
1549 }
1550 
1551 /**
1552  * event_trigger_unlock_commit - handle triggers and finish event commit
1553  * @file: The file pointer associated with the event
1554  * @buffer: The ring buffer that the event is being written to
1555  * @event: The event meta data in the ring buffer
1556  * @entry: The event itself
1557  * @trace_ctx: The tracing context flags.
1558  *
1559  * This is a helper function to handle triggers that require data
1560  * from the event itself. It also tests the event against filters and
1561  * if the event is soft disabled and should be discarded.
1562  */
1563 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)1564 event_trigger_unlock_commit(struct trace_event_file *file,
1565 			    struct trace_buffer *buffer,
1566 			    struct ring_buffer_event *event,
1567 			    void *entry, unsigned int trace_ctx)
1568 {
1569 	enum event_trigger_type tt = ETT_NONE;
1570 
1571 	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1572 		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1573 
1574 	if (tt)
1575 		event_triggers_post_call(file, tt);
1576 }
1577 
1578 #define FILTER_PRED_INVALID	((unsigned short)-1)
1579 #define FILTER_PRED_IS_RIGHT	(1 << 15)
1580 #define FILTER_PRED_FOLD	(1 << 15)
1581 
1582 /*
1583  * The max preds is the size of unsigned short with
1584  * two flags at the MSBs. One bit is used for both the IS_RIGHT
1585  * and FOLD flags. The other is reserved.
1586  *
1587  * 2^14 preds is way more than enough.
1588  */
1589 #define MAX_FILTER_PRED		16384
1590 
1591 struct filter_pred;
1592 struct regex;
1593 
1594 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1595 
1596 enum regex_type {
1597 	MATCH_FULL = 0,
1598 	MATCH_FRONT_ONLY,
1599 	MATCH_MIDDLE_ONLY,
1600 	MATCH_END_ONLY,
1601 	MATCH_GLOB,
1602 	MATCH_INDEX,
1603 };
1604 
1605 struct regex {
1606 	char			pattern[MAX_FILTER_STR_VAL];
1607 	int			len;
1608 	int			field_len;
1609 	regex_match_func	match;
1610 };
1611 
is_string_field(struct ftrace_event_field * field)1612 static inline bool is_string_field(struct ftrace_event_field *field)
1613 {
1614 	return field->filter_type == FILTER_DYN_STRING ||
1615 	       field->filter_type == FILTER_RDYN_STRING ||
1616 	       field->filter_type == FILTER_STATIC_STRING ||
1617 	       field->filter_type == FILTER_PTR_STRING ||
1618 	       field->filter_type == FILTER_COMM;
1619 }
1620 
is_function_field(struct ftrace_event_field * field)1621 static inline bool is_function_field(struct ftrace_event_field *field)
1622 {
1623 	return field->filter_type == FILTER_TRACE_FN;
1624 }
1625 
1626 extern enum regex_type
1627 filter_parse_regex(char *buff, int len, char **search, int *not);
1628 extern void print_event_filter(struct trace_event_file *file,
1629 			       struct trace_seq *s);
1630 extern int apply_event_filter(struct trace_event_file *file,
1631 			      char *filter_string);
1632 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1633 					char *filter_string);
1634 extern void print_subsystem_event_filter(struct event_subsystem *system,
1635 					 struct trace_seq *s);
1636 extern int filter_assign_type(const char *type);
1637 extern int create_event_filter(struct trace_array *tr,
1638 			       struct trace_event_call *call,
1639 			       char *filter_str, bool set_str,
1640 			       struct event_filter **filterp);
1641 extern void free_event_filter(struct event_filter *filter);
1642 
1643 struct ftrace_event_field *
1644 trace_find_event_field(struct trace_event_call *call, char *name);
1645 
1646 extern void trace_event_enable_cmd_record(bool enable);
1647 extern void trace_event_enable_tgid_record(bool enable);
1648 
1649 extern int event_trace_init(void);
1650 extern int init_events(void);
1651 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1652 extern int event_trace_del_tracer(struct trace_array *tr);
1653 extern void __trace_early_add_events(struct trace_array *tr);
1654 
1655 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1656 						  const char *system,
1657 						  const char *event);
1658 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1659 						const char *system,
1660 						const char *event);
1661 
event_file_data(struct file * filp)1662 static inline void *event_file_data(struct file *filp)
1663 {
1664 	return READ_ONCE(file_inode(filp)->i_private);
1665 }
1666 
1667 extern struct mutex event_mutex;
1668 extern struct list_head ftrace_events;
1669 
1670 /*
1671  * When the trace_event_file is the filp->i_private pointer,
1672  * it must be taken under the event_mutex lock, and then checked
1673  * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1674  * data pointed to by the trace_event_file can not be trusted.
1675  *
1676  * Use the event_file_file() to access the trace_event_file from
1677  * the filp the first time under the event_mutex and check for
1678  * NULL. If it is needed to be retrieved again and the event_mutex
1679  * is still held, then the event_file_data() can be used and it
1680  * is guaranteed to be valid.
1681  */
event_file_file(struct file * filp)1682 static inline struct trace_event_file *event_file_file(struct file *filp)
1683 {
1684 	struct trace_event_file *file;
1685 
1686 	lockdep_assert_held(&event_mutex);
1687 	file = READ_ONCE(file_inode(filp)->i_private);
1688 	if (!file || file->flags & EVENT_FILE_FL_FREED)
1689 		return NULL;
1690 	return file;
1691 }
1692 
1693 extern const struct file_operations event_trigger_fops;
1694 extern const struct file_operations event_hist_fops;
1695 extern const struct file_operations event_hist_debug_fops;
1696 extern const struct file_operations event_inject_fops;
1697 
1698 #ifdef CONFIG_HIST_TRIGGERS
1699 extern int register_trigger_hist_cmd(void);
1700 extern int register_trigger_hist_enable_disable_cmds(void);
1701 #else
register_trigger_hist_cmd(void)1702 static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1703 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1704 #endif
1705 
1706 extern int register_trigger_cmds(void);
1707 extern void clear_event_triggers(struct trace_array *tr);
1708 
1709 enum {
1710 	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1711 };
1712 
1713 struct event_trigger_data {
1714 	unsigned long			count;
1715 	int				ref;
1716 	int				flags;
1717 	struct event_trigger_ops	*ops;
1718 	struct event_command		*cmd_ops;
1719 	struct event_filter __rcu	*filter;
1720 	char				*filter_str;
1721 	void				*private_data;
1722 	bool				paused;
1723 	bool				paused_tmp;
1724 	struct list_head		list;
1725 	char				*name;
1726 	struct list_head		named_list;
1727 	struct event_trigger_data	*named_data;
1728 };
1729 
1730 /* Avoid typos */
1731 #define ENABLE_EVENT_STR	"enable_event"
1732 #define DISABLE_EVENT_STR	"disable_event"
1733 #define ENABLE_HIST_STR		"enable_hist"
1734 #define DISABLE_HIST_STR	"disable_hist"
1735 
1736 struct enable_trigger_data {
1737 	struct trace_event_file		*file;
1738 	bool				enable;
1739 	bool				hist;
1740 };
1741 
1742 extern int event_enable_trigger_print(struct seq_file *m,
1743 				      struct event_trigger_data *data);
1744 extern void event_enable_trigger_free(struct event_trigger_data *data);
1745 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1746 				      struct trace_event_file *file,
1747 				      char *glob, char *cmd,
1748 				      char *param_and_filter);
1749 extern int event_enable_register_trigger(char *glob,
1750 					 struct event_trigger_data *data,
1751 					 struct trace_event_file *file);
1752 extern void event_enable_unregister_trigger(char *glob,
1753 					    struct event_trigger_data *test,
1754 					    struct trace_event_file *file);
1755 extern void trigger_data_free(struct event_trigger_data *data);
1756 extern int event_trigger_init(struct event_trigger_data *data);
1757 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1758 					      int trigger_enable);
1759 extern void update_cond_flag(struct trace_event_file *file);
1760 extern int set_trigger_filter(char *filter_str,
1761 			      struct event_trigger_data *trigger_data,
1762 			      struct trace_event_file *file);
1763 extern struct event_trigger_data *find_named_trigger(const char *name);
1764 extern bool is_named_trigger(struct event_trigger_data *test);
1765 extern int save_named_trigger(const char *name,
1766 			      struct event_trigger_data *data);
1767 extern void del_named_trigger(struct event_trigger_data *data);
1768 extern void pause_named_trigger(struct event_trigger_data *data);
1769 extern void unpause_named_trigger(struct event_trigger_data *data);
1770 extern void set_named_trigger_data(struct event_trigger_data *data,
1771 				   struct event_trigger_data *named_data);
1772 extern struct event_trigger_data *
1773 get_named_trigger_data(struct event_trigger_data *data);
1774 extern int register_event_command(struct event_command *cmd);
1775 extern int unregister_event_command(struct event_command *cmd);
1776 extern int register_trigger_hist_enable_disable_cmds(void);
1777 extern bool event_trigger_check_remove(const char *glob);
1778 extern bool event_trigger_empty_param(const char *param);
1779 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1780 					 char **filter, bool param_required);
1781 extern struct event_trigger_data *
1782 event_trigger_alloc(struct event_command *cmd_ops,
1783 		    char *cmd,
1784 		    char *param,
1785 		    void *private_data);
1786 extern int event_trigger_parse_num(char *trigger,
1787 				   struct event_trigger_data *trigger_data);
1788 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1789 				    struct trace_event_file *file,
1790 				    char *param,
1791 				    struct event_trigger_data *trigger_data);
1792 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1793 				       struct event_trigger_data *trigger_data);
1794 extern int event_trigger_register(struct event_command *cmd_ops,
1795 				  struct trace_event_file *file,
1796 				  char *glob,
1797 				  struct event_trigger_data *trigger_data);
1798 extern void event_trigger_unregister(struct event_command *cmd_ops,
1799 				     struct trace_event_file *file,
1800 				     char *glob,
1801 				     struct event_trigger_data *trigger_data);
1802 
1803 extern void event_file_get(struct trace_event_file *file);
1804 extern void event_file_put(struct trace_event_file *file);
1805 
1806 /**
1807  * struct event_trigger_ops - callbacks for trace event triggers
1808  *
1809  * The methods in this structure provide per-event trigger hooks for
1810  * various trigger operations.
1811  *
1812  * The @init and @free methods are used during trigger setup and
1813  * teardown, typically called from an event_command's @parse()
1814  * function implementation.
1815  *
1816  * The @print method is used to print the trigger spec.
1817  *
1818  * The @trigger method is the function that actually implements the
1819  * trigger and is called in the context of the triggering event
1820  * whenever that event occurs.
1821  *
1822  * All the methods below, except for @init() and @free(), must be
1823  * implemented.
1824  *
1825  * @trigger: The trigger 'probe' function called when the triggering
1826  *	event occurs.  The data passed into this callback is the data
1827  *	that was supplied to the event_command @reg() function that
1828  *	registered the trigger (see struct event_command) along with
1829  *	the trace record, rec.
1830  *
1831  * @init: An optional initialization function called for the trigger
1832  *	when the trigger is registered (via the event_command reg()
1833  *	function).  This can be used to perform per-trigger
1834  *	initialization such as incrementing a per-trigger reference
1835  *	count, for instance.  This is usually implemented by the
1836  *	generic utility function @event_trigger_init() (see
1837  *	trace_event_triggers.c).
1838  *
1839  * @free: An optional de-initialization function called for the
1840  *	trigger when the trigger is unregistered (via the
1841  *	event_command @reg() function).  This can be used to perform
1842  *	per-trigger de-initialization such as decrementing a
1843  *	per-trigger reference count and freeing corresponding trigger
1844  *	data, for instance.  This is usually implemented by the
1845  *	generic utility function @event_trigger_free() (see
1846  *	trace_event_triggers.c).
1847  *
1848  * @print: The callback function invoked to have the trigger print
1849  *	itself.  This is usually implemented by a wrapper function
1850  *	that calls the generic utility function @event_trigger_print()
1851  *	(see trace_event_triggers.c).
1852  */
1853 struct event_trigger_ops {
1854 	void			(*trigger)(struct event_trigger_data *data,
1855 					   struct trace_buffer *buffer,
1856 					   void *rec,
1857 					   struct ring_buffer_event *rbe);
1858 	int			(*init)(struct event_trigger_data *data);
1859 	void			(*free)(struct event_trigger_data *data);
1860 	int			(*print)(struct seq_file *m,
1861 					 struct event_trigger_data *data);
1862 };
1863 
1864 /**
1865  * struct event_command - callbacks and data members for event commands
1866  *
1867  * Event commands are invoked by users by writing the command name
1868  * into the 'trigger' file associated with a trace event.  The
1869  * parameters associated with a specific invocation of an event
1870  * command are used to create an event trigger instance, which is
1871  * added to the list of trigger instances associated with that trace
1872  * event.  When the event is hit, the set of triggers associated with
1873  * that event is invoked.
1874  *
1875  * The data members in this structure provide per-event command data
1876  * for various event commands.
1877  *
1878  * All the data members below, except for @post_trigger, must be set
1879  * for each event command.
1880  *
1881  * @name: The unique name that identifies the event command.  This is
1882  *	the name used when setting triggers via trigger files.
1883  *
1884  * @trigger_type: A unique id that identifies the event command
1885  *	'type'.  This value has two purposes, the first to ensure that
1886  *	only one trigger of the same type can be set at a given time
1887  *	for a particular event e.g. it doesn't make sense to have both
1888  *	a traceon and traceoff trigger attached to a single event at
1889  *	the same time, so traceon and traceoff have the same type
1890  *	though they have different names.  The @trigger_type value is
1891  *	also used as a bit value for deferring the actual trigger
1892  *	action until after the current event is finished.  Some
1893  *	commands need to do this if they themselves log to the trace
1894  *	buffer (see the @post_trigger() member below).  @trigger_type
1895  *	values are defined by adding new values to the trigger_type
1896  *	enum in include/linux/trace_events.h.
1897  *
1898  * @flags: See the enum event_command_flags below.
1899  *
1900  * All the methods below, except for @set_filter() and @unreg_all(),
1901  * must be implemented.
1902  *
1903  * @parse: The callback function responsible for parsing and
1904  *	registering the trigger written to the 'trigger' file by the
1905  *	user.  It allocates the trigger instance and registers it with
1906  *	the appropriate trace event.  It makes use of the other
1907  *	event_command callback functions to orchestrate this, and is
1908  *	usually implemented by the generic utility function
1909  *	@event_trigger_callback() (see trace_event_triggers.c).
1910  *
1911  * @reg: Adds the trigger to the list of triggers associated with the
1912  *	event, and enables the event trigger itself, after
1913  *	initializing it (via the event_trigger_ops @init() function).
1914  *	This is also where commands can use the @trigger_type value to
1915  *	make the decision as to whether or not multiple instances of
1916  *	the trigger should be allowed.  This is usually implemented by
1917  *	the generic utility function @register_trigger() (see
1918  *	trace_event_triggers.c).
1919  *
1920  * @unreg: Removes the trigger from the list of triggers associated
1921  *	with the event, and disables the event trigger itself, after
1922  *	initializing it (via the event_trigger_ops @free() function).
1923  *	This is usually implemented by the generic utility function
1924  *	@unregister_trigger() (see trace_event_triggers.c).
1925  *
1926  * @unreg_all: An optional function called to remove all the triggers
1927  *	from the list of triggers associated with the event.  Called
1928  *	when a trigger file is opened in truncate mode.
1929  *
1930  * @set_filter: An optional function called to parse and set a filter
1931  *	for the trigger.  If no @set_filter() method is set for the
1932  *	event command, filters set by the user for the command will be
1933  *	ignored.  This is usually implemented by the generic utility
1934  *	function @set_trigger_filter() (see trace_event_triggers.c).
1935  *
1936  * @get_trigger_ops: The callback function invoked to retrieve the
1937  *	event_trigger_ops implementation associated with the command.
1938  *	This callback function allows a single event_command to
1939  *	support multiple trigger implementations via different sets of
1940  *	event_trigger_ops, depending on the value of the @param
1941  *	string.
1942  */
1943 struct event_command {
1944 	struct list_head	list;
1945 	char			*name;
1946 	enum event_trigger_type	trigger_type;
1947 	int			flags;
1948 	int			(*parse)(struct event_command *cmd_ops,
1949 					 struct trace_event_file *file,
1950 					 char *glob, char *cmd,
1951 					 char *param_and_filter);
1952 	int			(*reg)(char *glob,
1953 				       struct event_trigger_data *data,
1954 				       struct trace_event_file *file);
1955 	void			(*unreg)(char *glob,
1956 					 struct event_trigger_data *data,
1957 					 struct trace_event_file *file);
1958 	void			(*unreg_all)(struct trace_event_file *file);
1959 	int			(*set_filter)(char *filter_str,
1960 					      struct event_trigger_data *data,
1961 					      struct trace_event_file *file);
1962 	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1963 };
1964 
1965 /**
1966  * enum event_command_flags - flags for struct event_command
1967  *
1968  * @POST_TRIGGER: A flag that says whether or not this command needs
1969  *	to have its action delayed until after the current event has
1970  *	been closed.  Some triggers need to avoid being invoked while
1971  *	an event is currently in the process of being logged, since
1972  *	the trigger may itself log data into the trace buffer.  Thus
1973  *	we make sure the current event is committed before invoking
1974  *	those triggers.  To do that, the trigger invocation is split
1975  *	in two - the first part checks the filter using the current
1976  *	trace record; if a command has the @post_trigger flag set, it
1977  *	sets a bit for itself in the return value, otherwise it
1978  *	directly invokes the trigger.  Once all commands have been
1979  *	either invoked or set their return flag, the current record is
1980  *	either committed or discarded.  At that point, if any commands
1981  *	have deferred their triggers, those commands are finally
1982  *	invoked following the close of the current event.  In other
1983  *	words, if the event_trigger_ops @func() probe implementation
1984  *	itself logs to the trace buffer, this flag should be set,
1985  *	otherwise it can be left unspecified.
1986  *
1987  * @NEEDS_REC: A flag that says whether or not this command needs
1988  *	access to the trace record in order to perform its function,
1989  *	regardless of whether or not it has a filter associated with
1990  *	it (filters make a trigger require access to the trace record
1991  *	but are not always present).
1992  */
1993 enum event_command_flags {
1994 	EVENT_CMD_FL_POST_TRIGGER	= 1,
1995 	EVENT_CMD_FL_NEEDS_REC		= 2,
1996 };
1997 
event_command_post_trigger(struct event_command * cmd_ops)1998 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1999 {
2000 	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
2001 }
2002 
event_command_needs_rec(struct event_command * cmd_ops)2003 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
2004 {
2005 	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
2006 }
2007 
2008 extern int trace_event_enable_disable(struct trace_event_file *file,
2009 				      int enable, int soft_disable);
2010 extern int tracing_alloc_snapshot(void);
2011 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
2012 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
2013 
2014 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
2015 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2016 
2017 extern const char *__start___trace_bprintk_fmt[];
2018 extern const char *__stop___trace_bprintk_fmt[];
2019 
2020 extern const char *__start___tracepoint_str[];
2021 extern const char *__stop___tracepoint_str[];
2022 
2023 void trace_printk_control(bool enabled);
2024 void trace_printk_start_comm(void);
2025 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2026 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2027 
2028 /* Used from boot time tracer */
2029 extern int trace_set_options(struct trace_array *tr, char *option);
2030 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2031 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2032 					  unsigned long size, int cpu_id);
2033 extern int tracing_set_cpumask(struct trace_array *tr,
2034 				cpumask_var_t tracing_cpumask_new);
2035 
2036 
2037 #define MAX_EVENT_NAME_LEN	64
2038 
2039 extern ssize_t trace_parse_run_command(struct file *file,
2040 		const char __user *buffer, size_t count, loff_t *ppos,
2041 		int (*createfn)(const char *));
2042 
2043 extern unsigned int err_pos(char *cmd, const char *str);
2044 extern void tracing_log_err(struct trace_array *tr,
2045 			    const char *loc, const char *cmd,
2046 			    const char **errs, u8 type, u16 pos);
2047 
2048 /*
2049  * Normal trace_printk() and friends allocates special buffers
2050  * to do the manipulation, as well as saves the print formats
2051  * into sections to display. But the trace infrastructure wants
2052  * to use these without the added overhead at the price of being
2053  * a bit slower (used mainly for warnings, where we don't care
2054  * about performance). The internal_trace_puts() is for such
2055  * a purpose.
2056  */
2057 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2058 
2059 #undef FTRACE_ENTRY
2060 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2061 	extern struct trace_event_call					\
2062 	__aligned(4) event_##call;
2063 #undef FTRACE_ENTRY_DUP
2064 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2065 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2066 #undef FTRACE_ENTRY_PACKED
2067 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2068 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2069 
2070 #include "trace_entries.h"
2071 
2072 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2073 int perf_ftrace_event_register(struct trace_event_call *call,
2074 			       enum trace_reg type, void *data);
2075 #else
2076 #define perf_ftrace_event_register NULL
2077 #endif
2078 
2079 #ifdef CONFIG_FTRACE_SYSCALLS
2080 void init_ftrace_syscalls(void);
2081 const char *get_syscall_name(int syscall);
2082 #else
init_ftrace_syscalls(void)2083 static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)2084 static inline const char *get_syscall_name(int syscall)
2085 {
2086 	return NULL;
2087 }
2088 #endif
2089 
2090 #ifdef CONFIG_EVENT_TRACING
2091 void trace_event_init(void);
2092 void trace_event_eval_update(struct trace_eval_map **map, int len);
2093 /* Used from boot time tracer */
2094 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2095 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2096 #else
trace_event_init(void)2097 static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)2098 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2099 #endif
2100 
2101 #ifdef CONFIG_TRACER_SNAPSHOT
2102 void tracing_snapshot_instance(struct trace_array *tr);
2103 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2104 int tracing_arm_snapshot(struct trace_array *tr);
2105 void tracing_disarm_snapshot(struct trace_array *tr);
2106 #else
tracing_snapshot_instance(struct trace_array * tr)2107 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)2108 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2109 {
2110 	return 0;
2111 }
tracing_arm_snapshot(struct trace_array * tr)2112 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
tracing_disarm_snapshot(struct trace_array * tr)2113 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2114 #endif
2115 
2116 #ifdef CONFIG_PREEMPT_TRACER
2117 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2118 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2119 #else
tracer_preempt_on(unsigned long a0,unsigned long a1)2120 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)2121 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2122 #endif
2123 #ifdef CONFIG_IRQSOFF_TRACER
2124 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2125 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2126 #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)2127 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)2128 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2129 #endif
2130 
2131 /*
2132  * Reset the state of the trace_iterator so that it can read consumed data.
2133  * Normally, the trace_iterator is used for reading the data when it is not
2134  * consumed, and must retain state.
2135  */
trace_iterator_reset(struct trace_iterator * iter)2136 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2137 {
2138 	memset_startat(iter, 0, seq);
2139 	iter->pos = -1;
2140 }
2141 
2142 /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)2143 static inline bool __is_good_name(const char *name, bool hash_ok)
2144 {
2145 	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2146 		return false;
2147 	while (*++name != '\0') {
2148 		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2149 		    (!hash_ok || *name != '-'))
2150 			return false;
2151 	}
2152 	return true;
2153 }
2154 
2155 /* Check the name is good for event/group/fields */
is_good_name(const char * name)2156 static inline bool is_good_name(const char *name)
2157 {
2158 	return __is_good_name(name, false);
2159 }
2160 
2161 /* Check the name is good for system */
is_good_system_name(const char * name)2162 static inline bool is_good_system_name(const char *name)
2163 {
2164 	return __is_good_name(name, true);
2165 }
2166 
2167 /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)2168 static inline void sanitize_event_name(char *name)
2169 {
2170 	while (*name++ != '\0')
2171 		if (*name == ':' || *name == '.')
2172 			*name = '_';
2173 }
2174 
2175 /*
2176  * This is a generic way to read and write a u64 value from a file in tracefs.
2177  *
2178  * The value is stored on the variable pointed by *val. The value needs
2179  * to be at least *min and at most *max. The write is protected by an
2180  * existing *lock.
2181  */
2182 struct trace_min_max_param {
2183 	struct mutex	*lock;
2184 	u64		*val;
2185 	u64		*min;
2186 	u64		*max;
2187 };
2188 
2189 #define U64_STR_SIZE		24	/* 20 digits max */
2190 
2191 extern const struct file_operations trace_min_max_fops;
2192 
2193 #ifdef CONFIG_RV
2194 extern int rv_init_interface(void);
2195 #else
rv_init_interface(void)2196 static inline int rv_init_interface(void)
2197 {
2198 	return 0;
2199 }
2200 #endif
2201 
2202 /*
2203  * This is used only to distinguish
2204  * function address from trampoline code.
2205  * So this value has no meaning.
2206  */
2207 #define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2208 
2209 #endif /* _LINUX_KERNEL_TRACE_H */
2210