xref: /linux/kernel/trace/trace.h (revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd)
1 #ifndef _LINUX_KERNEL_TRACE_H
2 #define _LINUX_KERNEL_TRACE_H
3 
4 #include <linux/fs.h>
5 #include <linux/atomic.h>
6 #include <linux/sched.h>
7 #include <linux/clocksource.h>
8 #include <linux/ring_buffer.h>
9 #include <linux/mmiotrace.h>
10 #include <linux/tracepoint.h>
11 #include <linux/ftrace.h>
12 #include <linux/hw_breakpoint.h>
13 #include <linux/trace_seq.h>
14 #include <linux/ftrace_event.h>
15 
16 enum trace_type {
17 	__TRACE_FIRST_TYPE = 0,
18 
19 	TRACE_FN,
20 	TRACE_CTX,
21 	TRACE_WAKE,
22 	TRACE_STACK,
23 	TRACE_PRINT,
24 	TRACE_BPRINT,
25 	TRACE_MMIO_RW,
26 	TRACE_MMIO_MAP,
27 	TRACE_BRANCH,
28 	TRACE_GRAPH_RET,
29 	TRACE_GRAPH_ENT,
30 	TRACE_USER_STACK,
31 	TRACE_BLK,
32 
33 	__TRACE_LAST_TYPE,
34 };
35 
36 
37 #undef __field
38 #define __field(type, item)		type	item;
39 
40 #undef __field_struct
41 #define __field_struct(type, item)	__field(type, item)
42 
43 #undef __field_desc
44 #define __field_desc(type, container, item)
45 
46 #undef __array
47 #define __array(type, item, size)	type	item[size];
48 
49 #undef __array_desc
50 #define __array_desc(type, container, item, size)
51 
52 #undef __dynamic_array
53 #define __dynamic_array(type, item)	type	item[];
54 
55 #undef F_STRUCT
56 #define F_STRUCT(args...)		args
57 
58 #undef FTRACE_ENTRY
59 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
60 	struct struct_name {						\
61 		struct trace_entry	ent;				\
62 		tstruct							\
63 	}
64 
65 #undef TP_ARGS
66 #define TP_ARGS(args...)	args
67 
68 #undef FTRACE_ENTRY_DUP
69 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
70 
71 #undef FTRACE_ENTRY_REG
72 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	\
73 			 filter, regfn) \
74 	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
75 		     filter)
76 
77 #include "trace_entries.h"
78 
79 /*
80  * syscalls are special, and need special handling, this is why
81  * they are not included in trace_entries.h
82  */
83 struct syscall_trace_enter {
84 	struct trace_entry	ent;
85 	int			nr;
86 	unsigned long		args[];
87 };
88 
89 struct syscall_trace_exit {
90 	struct trace_entry	ent;
91 	int			nr;
92 	long			ret;
93 };
94 
95 struct kprobe_trace_entry_head {
96 	struct trace_entry	ent;
97 	unsigned long		ip;
98 };
99 
100 struct kretprobe_trace_entry_head {
101 	struct trace_entry	ent;
102 	unsigned long		func;
103 	unsigned long		ret_ip;
104 };
105 
106 /*
107  * trace_flag_type is an enumeration that holds different
108  * states when a trace occurs. These are:
109  *  IRQS_OFF		- interrupts were disabled
110  *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
111  *  NEED_RESCHED	- reschedule is requested
112  *  HARDIRQ		- inside an interrupt handler
113  *  SOFTIRQ		- inside a softirq handler
114  */
115 enum trace_flag_type {
116 	TRACE_FLAG_IRQS_OFF		= 0x01,
117 	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
118 	TRACE_FLAG_NEED_RESCHED		= 0x04,
119 	TRACE_FLAG_HARDIRQ		= 0x08,
120 	TRACE_FLAG_SOFTIRQ		= 0x10,
121 };
122 
123 #define TRACE_BUF_SIZE		1024
124 
125 /*
126  * The CPU trace array - it consists of thousands of trace entries
127  * plus some other descriptor data: (for example which task started
128  * the trace, etc.)
129  */
130 struct trace_array_cpu {
131 	atomic_t		disabled;
132 	void			*buffer_page;	/* ring buffer spare */
133 
134 	unsigned long		saved_latency;
135 	unsigned long		critical_start;
136 	unsigned long		critical_end;
137 	unsigned long		critical_sequence;
138 	unsigned long		nice;
139 	unsigned long		policy;
140 	unsigned long		rt_priority;
141 	unsigned long		skipped_entries;
142 	cycle_t			preempt_timestamp;
143 	pid_t			pid;
144 	uid_t			uid;
145 	char			comm[TASK_COMM_LEN];
146 };
147 
148 /*
149  * The trace array - an array of per-CPU trace arrays. This is the
150  * highest level data structure that individual tracers deal with.
151  * They have on/off state as well:
152  */
153 struct trace_array {
154 	struct ring_buffer	*buffer;
155 	unsigned long		entries;
156 	int			cpu;
157 	cycle_t			time_start;
158 	struct task_struct	*waiter;
159 	struct trace_array_cpu	*data[NR_CPUS];
160 };
161 
162 #define FTRACE_CMP_TYPE(var, type) \
163 	__builtin_types_compatible_p(typeof(var), type *)
164 
165 #undef IF_ASSIGN
166 #define IF_ASSIGN(var, entry, etype, id)		\
167 	if (FTRACE_CMP_TYPE(var, etype)) {		\
168 		var = (typeof(var))(entry);		\
169 		WARN_ON(id && (entry)->type != id);	\
170 		break;					\
171 	}
172 
173 /* Will cause compile errors if type is not found. */
174 extern void __ftrace_bad_type(void);
175 
176 /*
177  * The trace_assign_type is a verifier that the entry type is
178  * the same as the type being assigned. To add new types simply
179  * add a line with the following format:
180  *
181  * IF_ASSIGN(var, ent, type, id);
182  *
183  *  Where "type" is the trace type that includes the trace_entry
184  *  as the "ent" item. And "id" is the trace identifier that is
185  *  used in the trace_type enum.
186  *
187  *  If the type can have more than one id, then use zero.
188  */
189 #define trace_assign_type(var, ent)					\
190 	do {								\
191 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
192 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
193 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
194 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
195 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
196 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
197 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
198 			  TRACE_MMIO_RW);				\
199 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
200 			  TRACE_MMIO_MAP);				\
201 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
202 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
203 			  TRACE_GRAPH_ENT);		\
204 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
205 			  TRACE_GRAPH_RET);		\
206 		__ftrace_bad_type();					\
207 	} while (0)
208 
209 /*
210  * An option specific to a tracer. This is a boolean value.
211  * The bit is the bit index that sets its value on the
212  * flags value in struct tracer_flags.
213  */
214 struct tracer_opt {
215 	const char	*name; /* Will appear on the trace_options file */
216 	u32		bit; /* Mask assigned in val field in tracer_flags */
217 };
218 
219 /*
220  * The set of specific options for a tracer. Your tracer
221  * have to set the initial value of the flags val.
222  */
223 struct tracer_flags {
224 	u32			val;
225 	struct tracer_opt	*opts;
226 };
227 
228 /* Makes more easy to define a tracer opt */
229 #define TRACER_OPT(s, b)	.name = #s, .bit = b
230 
231 
232 /**
233  * struct tracer - a specific tracer and its callbacks to interact with debugfs
234  * @name: the name chosen to select it on the available_tracers file
235  * @init: called when one switches to this tracer (echo name > current_tracer)
236  * @reset: called when one switches to another tracer
237  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
238  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
239  * @open: called when the trace file is opened
240  * @pipe_open: called when the trace_pipe file is opened
241  * @wait_pipe: override how the user waits for traces on trace_pipe
242  * @close: called when the trace file is released
243  * @pipe_close: called when the trace_pipe file is released
244  * @read: override the default read callback on trace_pipe
245  * @splice_read: override the default splice_read callback on trace_pipe
246  * @selftest: selftest to run on boot (see trace_selftest.c)
247  * @print_headers: override the first lines that describe your columns
248  * @print_line: callback that prints a trace
249  * @set_flag: signals one of your private flags changed (trace_options file)
250  * @flags: your private flags
251  */
252 struct tracer {
253 	const char		*name;
254 	int			(*init)(struct trace_array *tr);
255 	void			(*reset)(struct trace_array *tr);
256 	void			(*start)(struct trace_array *tr);
257 	void			(*stop)(struct trace_array *tr);
258 	void			(*open)(struct trace_iterator *iter);
259 	void			(*pipe_open)(struct trace_iterator *iter);
260 	void			(*wait_pipe)(struct trace_iterator *iter);
261 	void			(*close)(struct trace_iterator *iter);
262 	void			(*pipe_close)(struct trace_iterator *iter);
263 	ssize_t			(*read)(struct trace_iterator *iter,
264 					struct file *filp, char __user *ubuf,
265 					size_t cnt, loff_t *ppos);
266 	ssize_t			(*splice_read)(struct trace_iterator *iter,
267 					       struct file *filp,
268 					       loff_t *ppos,
269 					       struct pipe_inode_info *pipe,
270 					       size_t len,
271 					       unsigned int flags);
272 #ifdef CONFIG_FTRACE_STARTUP_TEST
273 	int			(*selftest)(struct tracer *trace,
274 					    struct trace_array *tr);
275 #endif
276 	void			(*print_header)(struct seq_file *m);
277 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
278 	/* If you handled the flag setting, return 0 */
279 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
280 	struct tracer		*next;
281 	struct tracer_flags	*flags;
282 	int			print_max;
283 	int			use_max_tr;
284 };
285 
286 
287 /* Only current can touch trace_recursion */
288 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
289 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
290 
291 /* Ring buffer has the 10 LSB bits to count */
292 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
293 
294 /* for function tracing recursion */
295 #define TRACE_INTERNAL_BIT		(1<<11)
296 #define TRACE_GLOBAL_BIT		(1<<12)
297 #define TRACE_CONTROL_BIT		(1<<13)
298 
299 /*
300  * Abuse of the trace_recursion.
301  * As we need a way to maintain state if we are tracing the function
302  * graph in irq because we want to trace a particular function that
303  * was called in irq context but we have irq tracing off. Since this
304  * can only be modified by current, we can reuse trace_recursion.
305  */
306 #define TRACE_IRQ_BIT			(1<<13)
307 
308 #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (bit); } while (0)
309 #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(bit); } while (0)
310 #define trace_recursion_test(bit)	((current)->trace_recursion & (bit))
311 
312 #define TRACE_PIPE_ALL_CPU	-1
313 
314 int tracer_init(struct tracer *t, struct trace_array *tr);
315 int tracing_is_enabled(void);
316 void trace_wake_up(void);
317 void tracing_reset(struct trace_array *tr, int cpu);
318 void tracing_reset_online_cpus(struct trace_array *tr);
319 void tracing_reset_current(int cpu);
320 void tracing_reset_current_online_cpus(void);
321 int tracing_open_generic(struct inode *inode, struct file *filp);
322 struct dentry *trace_create_file(const char *name,
323 				 umode_t mode,
324 				 struct dentry *parent,
325 				 void *data,
326 				 const struct file_operations *fops);
327 
328 struct dentry *tracing_init_dentry(void);
329 
330 struct ring_buffer_event;
331 
332 struct ring_buffer_event *
333 trace_buffer_lock_reserve(struct ring_buffer *buffer,
334 			  int type,
335 			  unsigned long len,
336 			  unsigned long flags,
337 			  int pc);
338 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
339 				struct ring_buffer_event *event,
340 				unsigned long flags, int pc);
341 
342 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
343 						struct trace_array_cpu *data);
344 
345 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
346 					  int *ent_cpu, u64 *ent_ts);
347 
348 int trace_empty(struct trace_iterator *iter);
349 
350 void *trace_find_next_entry_inc(struct trace_iterator *iter);
351 
352 void trace_init_global_iter(struct trace_iterator *iter);
353 
354 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
355 
356 void default_wait_pipe(struct trace_iterator *iter);
357 void poll_wait_pipe(struct trace_iterator *iter);
358 
359 void ftrace(struct trace_array *tr,
360 			    struct trace_array_cpu *data,
361 			    unsigned long ip,
362 			    unsigned long parent_ip,
363 			    unsigned long flags, int pc);
364 void tracing_sched_switch_trace(struct trace_array *tr,
365 				struct task_struct *prev,
366 				struct task_struct *next,
367 				unsigned long flags, int pc);
368 
369 void tracing_sched_wakeup_trace(struct trace_array *tr,
370 				struct task_struct *wakee,
371 				struct task_struct *cur,
372 				unsigned long flags, int pc);
373 void trace_function(struct trace_array *tr,
374 		    unsigned long ip,
375 		    unsigned long parent_ip,
376 		    unsigned long flags, int pc);
377 void trace_graph_function(struct trace_array *tr,
378 		    unsigned long ip,
379 		    unsigned long parent_ip,
380 		    unsigned long flags, int pc);
381 void trace_latency_header(struct seq_file *m);
382 void trace_default_header(struct seq_file *m);
383 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
384 int trace_empty(struct trace_iterator *iter);
385 
386 void trace_graph_return(struct ftrace_graph_ret *trace);
387 int trace_graph_entry(struct ftrace_graph_ent *trace);
388 void set_graph_array(struct trace_array *tr);
389 
390 void tracing_start_cmdline_record(void);
391 void tracing_stop_cmdline_record(void);
392 void tracing_sched_switch_assign_trace(struct trace_array *tr);
393 void tracing_stop_sched_switch_record(void);
394 void tracing_start_sched_switch_record(void);
395 int register_tracer(struct tracer *type);
396 void unregister_tracer(struct tracer *type);
397 int is_tracing_stopped(void);
398 enum trace_file_type {
399 	TRACE_FILE_LAT_FMT	= 1,
400 	TRACE_FILE_ANNOTATE	= 2,
401 };
402 
403 extern cpumask_var_t __read_mostly tracing_buffer_mask;
404 
405 #define for_each_tracing_cpu(cpu)	\
406 	for_each_cpu(cpu, tracing_buffer_mask)
407 
408 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
409 
410 extern unsigned long tracing_thresh;
411 
412 #ifdef CONFIG_TRACER_MAX_TRACE
413 extern unsigned long tracing_max_latency;
414 
415 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
416 void update_max_tr_single(struct trace_array *tr,
417 			  struct task_struct *tsk, int cpu);
418 #endif /* CONFIG_TRACER_MAX_TRACE */
419 
420 #ifdef CONFIG_STACKTRACE
421 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
422 			int skip, int pc);
423 
424 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
425 			     int skip, int pc, struct pt_regs *regs);
426 
427 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
428 			    int pc);
429 
430 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
431 		   int pc);
432 #else
433 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
434 				      unsigned long flags, int skip, int pc)
435 {
436 }
437 
438 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
439 					   unsigned long flags, int skip,
440 					   int pc, struct pt_regs *regs)
441 {
442 }
443 
444 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
445 					  unsigned long flags, int pc)
446 {
447 }
448 
449 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
450 				 int skip, int pc)
451 {
452 }
453 #endif /* CONFIG_STACKTRACE */
454 
455 extern cycle_t ftrace_now(int cpu);
456 
457 extern void trace_find_cmdline(int pid, char comm[]);
458 
459 #ifdef CONFIG_DYNAMIC_FTRACE
460 extern unsigned long ftrace_update_tot_cnt;
461 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
462 extern int DYN_FTRACE_TEST_NAME(void);
463 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
464 extern int DYN_FTRACE_TEST_NAME2(void);
465 #endif
466 
467 extern int ring_buffer_expanded;
468 extern bool tracing_selftest_disabled;
469 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
470 
471 #ifdef CONFIG_FTRACE_STARTUP_TEST
472 extern int trace_selftest_startup_function(struct tracer *trace,
473 					   struct trace_array *tr);
474 extern int trace_selftest_startup_function_graph(struct tracer *trace,
475 						 struct trace_array *tr);
476 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
477 					  struct trace_array *tr);
478 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
479 					     struct trace_array *tr);
480 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
481 						 struct trace_array *tr);
482 extern int trace_selftest_startup_wakeup(struct tracer *trace,
483 					 struct trace_array *tr);
484 extern int trace_selftest_startup_nop(struct tracer *trace,
485 					 struct trace_array *tr);
486 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
487 					       struct trace_array *tr);
488 extern int trace_selftest_startup_branch(struct tracer *trace,
489 					 struct trace_array *tr);
490 #endif /* CONFIG_FTRACE_STARTUP_TEST */
491 
492 extern void *head_page(struct trace_array_cpu *data);
493 extern unsigned long long ns2usecs(cycle_t nsec);
494 extern int
495 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
496 extern int
497 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
498 extern int
499 trace_array_vprintk(struct trace_array *tr,
500 		    unsigned long ip, const char *fmt, va_list args);
501 int trace_array_printk(struct trace_array *tr,
502 		       unsigned long ip, const char *fmt, ...);
503 void trace_printk_seq(struct trace_seq *s);
504 enum print_line_t print_trace_line(struct trace_iterator *iter);
505 
506 extern unsigned long trace_flags;
507 
508 extern int trace_clock_id;
509 
510 /* Standard output formatting function used for function return traces */
511 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
512 
513 /* Flag options */
514 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
515 #define TRACE_GRAPH_PRINT_CPU           0x2
516 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
517 #define TRACE_GRAPH_PRINT_PROC          0x8
518 #define TRACE_GRAPH_PRINT_DURATION      0x10
519 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
520 
521 extern enum print_line_t
522 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
523 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
524 extern enum print_line_t
525 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
526 extern void graph_trace_open(struct trace_iterator *iter);
527 extern void graph_trace_close(struct trace_iterator *iter);
528 extern int __trace_graph_entry(struct trace_array *tr,
529 			       struct ftrace_graph_ent *trace,
530 			       unsigned long flags, int pc);
531 extern void __trace_graph_return(struct trace_array *tr,
532 				 struct ftrace_graph_ret *trace,
533 				 unsigned long flags, int pc);
534 
535 
536 #ifdef CONFIG_DYNAMIC_FTRACE
537 /* TODO: make this variable */
538 #define FTRACE_GRAPH_MAX_FUNCS		32
539 extern int ftrace_graph_filter_enabled;
540 extern int ftrace_graph_count;
541 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
542 
543 static inline int ftrace_graph_addr(unsigned long addr)
544 {
545 	int i;
546 
547 	if (!ftrace_graph_filter_enabled)
548 		return 1;
549 
550 	for (i = 0; i < ftrace_graph_count; i++) {
551 		if (addr == ftrace_graph_funcs[i]) {
552 			/*
553 			 * If no irqs are to be traced, but a set_graph_function
554 			 * is set, and called by an interrupt handler, we still
555 			 * want to trace it.
556 			 */
557 			if (in_irq())
558 				trace_recursion_set(TRACE_IRQ_BIT);
559 			else
560 				trace_recursion_clear(TRACE_IRQ_BIT);
561 			return 1;
562 		}
563 	}
564 
565 	return 0;
566 }
567 #else
568 static inline int ftrace_graph_addr(unsigned long addr)
569 {
570 	return 1;
571 }
572 #endif /* CONFIG_DYNAMIC_FTRACE */
573 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
574 static inline enum print_line_t
575 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
576 {
577 	return TRACE_TYPE_UNHANDLED;
578 }
579 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
580 
581 extern struct list_head ftrace_pids;
582 
583 #ifdef CONFIG_FUNCTION_TRACER
584 static inline int ftrace_trace_task(struct task_struct *task)
585 {
586 	if (list_empty(&ftrace_pids))
587 		return 1;
588 
589 	return test_tsk_trace_trace(task);
590 }
591 extern int ftrace_is_dead(void);
592 #else
593 static inline int ftrace_trace_task(struct task_struct *task)
594 {
595 	return 1;
596 }
597 static inline int ftrace_is_dead(void) { return 0; }
598 #endif
599 
600 int ftrace_event_is_function(struct ftrace_event_call *call);
601 
602 /*
603  * struct trace_parser - servers for reading the user input separated by spaces
604  * @cont: set if the input is not complete - no final space char was found
605  * @buffer: holds the parsed user input
606  * @idx: user input length
607  * @size: buffer size
608  */
609 struct trace_parser {
610 	bool		cont;
611 	char		*buffer;
612 	unsigned	idx;
613 	unsigned	size;
614 };
615 
616 static inline bool trace_parser_loaded(struct trace_parser *parser)
617 {
618 	return (parser->idx != 0);
619 }
620 
621 static inline bool trace_parser_cont(struct trace_parser *parser)
622 {
623 	return parser->cont;
624 }
625 
626 static inline void trace_parser_clear(struct trace_parser *parser)
627 {
628 	parser->cont = false;
629 	parser->idx = 0;
630 }
631 
632 extern int trace_parser_get_init(struct trace_parser *parser, int size);
633 extern void trace_parser_put(struct trace_parser *parser);
634 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
635 	size_t cnt, loff_t *ppos);
636 
637 /*
638  * trace_iterator_flags is an enumeration that defines bit
639  * positions into trace_flags that controls the output.
640  *
641  * NOTE: These bits must match the trace_options array in
642  *       trace.c.
643  */
644 enum trace_iterator_flags {
645 	TRACE_ITER_PRINT_PARENT		= 0x01,
646 	TRACE_ITER_SYM_OFFSET		= 0x02,
647 	TRACE_ITER_SYM_ADDR		= 0x04,
648 	TRACE_ITER_VERBOSE		= 0x08,
649 	TRACE_ITER_RAW			= 0x10,
650 	TRACE_ITER_HEX			= 0x20,
651 	TRACE_ITER_BIN			= 0x40,
652 	TRACE_ITER_BLOCK		= 0x80,
653 	TRACE_ITER_STACKTRACE		= 0x100,
654 	TRACE_ITER_PRINTK		= 0x200,
655 	TRACE_ITER_PREEMPTONLY		= 0x400,
656 	TRACE_ITER_BRANCH		= 0x800,
657 	TRACE_ITER_ANNOTATE		= 0x1000,
658 	TRACE_ITER_USERSTACKTRACE       = 0x2000,
659 	TRACE_ITER_SYM_USEROBJ          = 0x4000,
660 	TRACE_ITER_PRINTK_MSGONLY	= 0x8000,
661 	TRACE_ITER_CONTEXT_INFO		= 0x10000, /* Print pid/cpu/time */
662 	TRACE_ITER_LATENCY_FMT		= 0x20000,
663 	TRACE_ITER_SLEEP_TIME		= 0x40000,
664 	TRACE_ITER_GRAPH_TIME		= 0x80000,
665 	TRACE_ITER_RECORD_CMD		= 0x100000,
666 	TRACE_ITER_OVERWRITE		= 0x200000,
667 	TRACE_ITER_STOP_ON_FREE		= 0x400000,
668 	TRACE_ITER_IRQ_INFO		= 0x800000,
669 };
670 
671 /*
672  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
673  * control the output of kernel symbols.
674  */
675 #define TRACE_ITER_SYM_MASK \
676 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
677 
678 extern struct tracer nop_trace;
679 
680 #ifdef CONFIG_BRANCH_TRACER
681 extern int enable_branch_tracing(struct trace_array *tr);
682 extern void disable_branch_tracing(void);
683 static inline int trace_branch_enable(struct trace_array *tr)
684 {
685 	if (trace_flags & TRACE_ITER_BRANCH)
686 		return enable_branch_tracing(tr);
687 	return 0;
688 }
689 static inline void trace_branch_disable(void)
690 {
691 	/* due to races, always disable */
692 	disable_branch_tracing();
693 }
694 #else
695 static inline int trace_branch_enable(struct trace_array *tr)
696 {
697 	return 0;
698 }
699 static inline void trace_branch_disable(void)
700 {
701 }
702 #endif /* CONFIG_BRANCH_TRACER */
703 
704 /* set ring buffers to default size if not already done so */
705 int tracing_update_buffers(void);
706 
707 /* trace event type bit fields, not numeric */
708 enum {
709 	TRACE_EVENT_TYPE_PRINTF		= 1,
710 	TRACE_EVENT_TYPE_RAW		= 2,
711 };
712 
713 struct ftrace_event_field {
714 	struct list_head	link;
715 	char			*name;
716 	char			*type;
717 	int			filter_type;
718 	int			offset;
719 	int			size;
720 	int			is_signed;
721 };
722 
723 struct event_filter {
724 	int			n_preds;	/* Number assigned */
725 	int			a_preds;	/* allocated */
726 	struct filter_pred	*preds;
727 	struct filter_pred	*root;
728 	char			*filter_string;
729 };
730 
731 struct event_subsystem {
732 	struct list_head	list;
733 	const char		*name;
734 	struct dentry		*entry;
735 	struct event_filter	*filter;
736 	int			nr_events;
737 	int			ref_count;
738 };
739 
740 #define FILTER_PRED_INVALID	((unsigned short)-1)
741 #define FILTER_PRED_IS_RIGHT	(1 << 15)
742 #define FILTER_PRED_FOLD	(1 << 15)
743 
744 /*
745  * The max preds is the size of unsigned short with
746  * two flags at the MSBs. One bit is used for both the IS_RIGHT
747  * and FOLD flags. The other is reserved.
748  *
749  * 2^14 preds is way more than enough.
750  */
751 #define MAX_FILTER_PRED		16384
752 
753 struct filter_pred;
754 struct regex;
755 
756 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
757 
758 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
759 
760 enum regex_type {
761 	MATCH_FULL = 0,
762 	MATCH_FRONT_ONLY,
763 	MATCH_MIDDLE_ONLY,
764 	MATCH_END_ONLY,
765 };
766 
767 struct regex {
768 	char			pattern[MAX_FILTER_STR_VAL];
769 	int			len;
770 	int			field_len;
771 	regex_match_func	match;
772 };
773 
774 struct filter_pred {
775 	filter_pred_fn_t 	fn;
776 	u64 			val;
777 	struct regex		regex;
778 	unsigned short		*ops;
779 	struct ftrace_event_field *field;
780 	int 			offset;
781 	int 			not;
782 	int 			op;
783 	unsigned short		index;
784 	unsigned short		parent;
785 	unsigned short		left;
786 	unsigned short		right;
787 };
788 
789 extern struct list_head ftrace_common_fields;
790 
791 extern enum regex_type
792 filter_parse_regex(char *buff, int len, char **search, int *not);
793 extern void print_event_filter(struct ftrace_event_call *call,
794 			       struct trace_seq *s);
795 extern int apply_event_filter(struct ftrace_event_call *call,
796 			      char *filter_string);
797 extern int apply_subsystem_event_filter(struct event_subsystem *system,
798 					char *filter_string);
799 extern void print_subsystem_event_filter(struct event_subsystem *system,
800 					 struct trace_seq *s);
801 extern int filter_assign_type(const char *type);
802 
803 struct list_head *
804 trace_get_fields(struct ftrace_event_call *event_call);
805 
806 static inline int
807 filter_check_discard(struct ftrace_event_call *call, void *rec,
808 		     struct ring_buffer *buffer,
809 		     struct ring_buffer_event *event)
810 {
811 	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
812 	    !filter_match_preds(call->filter, rec)) {
813 		ring_buffer_discard_commit(buffer, event);
814 		return 1;
815 	}
816 
817 	return 0;
818 }
819 
820 extern void trace_event_enable_cmd_record(bool enable);
821 
822 extern struct mutex event_mutex;
823 extern struct list_head ftrace_events;
824 
825 extern const char *__start___trace_bprintk_fmt[];
826 extern const char *__stop___trace_bprintk_fmt[];
827 
828 #undef FTRACE_ENTRY
829 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
830 	extern struct ftrace_event_call					\
831 	__attribute__((__aligned__(4))) event_##call;
832 #undef FTRACE_ENTRY_DUP
833 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
834 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
835 		     filter)
836 #include "trace_entries.h"
837 
838 #ifdef CONFIG_PERF_EVENTS
839 #ifdef CONFIG_FUNCTION_TRACER
840 int perf_ftrace_event_register(struct ftrace_event_call *call,
841 			       enum trace_reg type, void *data);
842 #else
843 #define perf_ftrace_event_register NULL
844 #endif /* CONFIG_FUNCTION_TRACER */
845 #endif /* CONFIG_PERF_EVENTS */
846 
847 #endif /* _LINUX_KERNEL_TRACE_H */
848