xref: /linux/kernel/trace/trace.h (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
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 struct uprobe_trace_entry_head {
107 	struct trace_entry	ent;
108 	unsigned long		ip;
109 };
110 
111 /*
112  * trace_flag_type is an enumeration that holds different
113  * states when a trace occurs. These are:
114  *  IRQS_OFF		- interrupts were disabled
115  *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
116  *  NEED_RESCHED	- reschedule is requested
117  *  HARDIRQ		- inside an interrupt handler
118  *  SOFTIRQ		- inside a softirq handler
119  */
120 enum trace_flag_type {
121 	TRACE_FLAG_IRQS_OFF		= 0x01,
122 	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
123 	TRACE_FLAG_NEED_RESCHED		= 0x04,
124 	TRACE_FLAG_HARDIRQ		= 0x08,
125 	TRACE_FLAG_SOFTIRQ		= 0x10,
126 };
127 
128 #define TRACE_BUF_SIZE		1024
129 
130 /*
131  * The CPU trace array - it consists of thousands of trace entries
132  * plus some other descriptor data: (for example which task started
133  * the trace, etc.)
134  */
135 struct trace_array_cpu {
136 	atomic_t		disabled;
137 	void			*buffer_page;	/* ring buffer spare */
138 
139 	unsigned long		entries;
140 	unsigned long		saved_latency;
141 	unsigned long		critical_start;
142 	unsigned long		critical_end;
143 	unsigned long		critical_sequence;
144 	unsigned long		nice;
145 	unsigned long		policy;
146 	unsigned long		rt_priority;
147 	unsigned long		skipped_entries;
148 	cycle_t			preempt_timestamp;
149 	pid_t			pid;
150 	kuid_t			uid;
151 	char			comm[TASK_COMM_LEN];
152 };
153 
154 /*
155  * The trace array - an array of per-CPU trace arrays. This is the
156  * highest level data structure that individual tracers deal with.
157  * They have on/off state as well:
158  */
159 struct trace_array {
160 	struct ring_buffer	*buffer;
161 	int			cpu;
162 	int			buffer_disabled;
163 	cycle_t			time_start;
164 	struct task_struct	*waiter;
165 	struct trace_array_cpu	*data[NR_CPUS];
166 };
167 
168 #define FTRACE_CMP_TYPE(var, type) \
169 	__builtin_types_compatible_p(typeof(var), type *)
170 
171 #undef IF_ASSIGN
172 #define IF_ASSIGN(var, entry, etype, id)		\
173 	if (FTRACE_CMP_TYPE(var, etype)) {		\
174 		var = (typeof(var))(entry);		\
175 		WARN_ON(id && (entry)->type != id);	\
176 		break;					\
177 	}
178 
179 /* Will cause compile errors if type is not found. */
180 extern void __ftrace_bad_type(void);
181 
182 /*
183  * The trace_assign_type is a verifier that the entry type is
184  * the same as the type being assigned. To add new types simply
185  * add a line with the following format:
186  *
187  * IF_ASSIGN(var, ent, type, id);
188  *
189  *  Where "type" is the trace type that includes the trace_entry
190  *  as the "ent" item. And "id" is the trace identifier that is
191  *  used in the trace_type enum.
192  *
193  *  If the type can have more than one id, then use zero.
194  */
195 #define trace_assign_type(var, ent)					\
196 	do {								\
197 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
198 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
199 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
200 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
201 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
202 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
203 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
204 			  TRACE_MMIO_RW);				\
205 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
206 			  TRACE_MMIO_MAP);				\
207 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
208 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
209 			  TRACE_GRAPH_ENT);		\
210 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
211 			  TRACE_GRAPH_RET);		\
212 		__ftrace_bad_type();					\
213 	} while (0)
214 
215 /*
216  * An option specific to a tracer. This is a boolean value.
217  * The bit is the bit index that sets its value on the
218  * flags value in struct tracer_flags.
219  */
220 struct tracer_opt {
221 	const char	*name; /* Will appear on the trace_options file */
222 	u32		bit; /* Mask assigned in val field in tracer_flags */
223 };
224 
225 /*
226  * The set of specific options for a tracer. Your tracer
227  * have to set the initial value of the flags val.
228  */
229 struct tracer_flags {
230 	u32			val;
231 	struct tracer_opt	*opts;
232 };
233 
234 /* Makes more easy to define a tracer opt */
235 #define TRACER_OPT(s, b)	.name = #s, .bit = b
236 
237 
238 /**
239  * struct tracer - a specific tracer and its callbacks to interact with debugfs
240  * @name: the name chosen to select it on the available_tracers file
241  * @init: called when one switches to this tracer (echo name > current_tracer)
242  * @reset: called when one switches to another tracer
243  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
244  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
245  * @open: called when the trace file is opened
246  * @pipe_open: called when the trace_pipe file is opened
247  * @wait_pipe: override how the user waits for traces on trace_pipe
248  * @close: called when the trace file is released
249  * @pipe_close: called when the trace_pipe file is released
250  * @read: override the default read callback on trace_pipe
251  * @splice_read: override the default splice_read callback on trace_pipe
252  * @selftest: selftest to run on boot (see trace_selftest.c)
253  * @print_headers: override the first lines that describe your columns
254  * @print_line: callback that prints a trace
255  * @set_flag: signals one of your private flags changed (trace_options file)
256  * @flags: your private flags
257  */
258 struct tracer {
259 	const char		*name;
260 	int			(*init)(struct trace_array *tr);
261 	void			(*reset)(struct trace_array *tr);
262 	void			(*start)(struct trace_array *tr);
263 	void			(*stop)(struct trace_array *tr);
264 	void			(*open)(struct trace_iterator *iter);
265 	void			(*pipe_open)(struct trace_iterator *iter);
266 	void			(*wait_pipe)(struct trace_iterator *iter);
267 	void			(*close)(struct trace_iterator *iter);
268 	void			(*pipe_close)(struct trace_iterator *iter);
269 	ssize_t			(*read)(struct trace_iterator *iter,
270 					struct file *filp, char __user *ubuf,
271 					size_t cnt, loff_t *ppos);
272 	ssize_t			(*splice_read)(struct trace_iterator *iter,
273 					       struct file *filp,
274 					       loff_t *ppos,
275 					       struct pipe_inode_info *pipe,
276 					       size_t len,
277 					       unsigned int flags);
278 #ifdef CONFIG_FTRACE_STARTUP_TEST
279 	int			(*selftest)(struct tracer *trace,
280 					    struct trace_array *tr);
281 #endif
282 	void			(*print_header)(struct seq_file *m);
283 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
284 	/* If you handled the flag setting, return 0 */
285 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
286 	struct tracer		*next;
287 	struct tracer_flags	*flags;
288 	bool			print_max;
289 	bool			use_max_tr;
290 };
291 
292 
293 /* Only current can touch trace_recursion */
294 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
295 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
296 
297 /* Ring buffer has the 10 LSB bits to count */
298 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
299 
300 /* for function tracing recursion */
301 #define TRACE_INTERNAL_BIT		(1<<11)
302 #define TRACE_GLOBAL_BIT		(1<<12)
303 #define TRACE_CONTROL_BIT		(1<<13)
304 
305 /*
306  * Abuse of the trace_recursion.
307  * As we need a way to maintain state if we are tracing the function
308  * graph in irq because we want to trace a particular function that
309  * was called in irq context but we have irq tracing off. Since this
310  * can only be modified by current, we can reuse trace_recursion.
311  */
312 #define TRACE_IRQ_BIT			(1<<13)
313 
314 #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (bit); } while (0)
315 #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(bit); } while (0)
316 #define trace_recursion_test(bit)	((current)->trace_recursion & (bit))
317 
318 #define TRACE_PIPE_ALL_CPU	-1
319 
320 static inline struct ring_buffer_iter *
321 trace_buffer_iter(struct trace_iterator *iter, int cpu)
322 {
323 	if (iter->buffer_iter && iter->buffer_iter[cpu])
324 		return iter->buffer_iter[cpu];
325 	return NULL;
326 }
327 
328 int tracer_init(struct tracer *t, struct trace_array *tr);
329 int tracing_is_enabled(void);
330 void tracing_reset(struct trace_array *tr, int cpu);
331 void tracing_reset_online_cpus(struct trace_array *tr);
332 void tracing_reset_current(int cpu);
333 void tracing_reset_current_online_cpus(void);
334 int tracing_open_generic(struct inode *inode, struct file *filp);
335 struct dentry *trace_create_file(const char *name,
336 				 umode_t mode,
337 				 struct dentry *parent,
338 				 void *data,
339 				 const struct file_operations *fops);
340 
341 struct dentry *tracing_init_dentry(void);
342 
343 struct ring_buffer_event;
344 
345 struct ring_buffer_event *
346 trace_buffer_lock_reserve(struct ring_buffer *buffer,
347 			  int type,
348 			  unsigned long len,
349 			  unsigned long flags,
350 			  int pc);
351 
352 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
353 						struct trace_array_cpu *data);
354 
355 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
356 					  int *ent_cpu, u64 *ent_ts);
357 
358 void __buffer_unlock_commit(struct ring_buffer *buffer,
359 			    struct ring_buffer_event *event);
360 
361 int trace_empty(struct trace_iterator *iter);
362 
363 void *trace_find_next_entry_inc(struct trace_iterator *iter);
364 
365 void trace_init_global_iter(struct trace_iterator *iter);
366 
367 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
368 
369 void poll_wait_pipe(struct trace_iterator *iter);
370 
371 void ftrace(struct trace_array *tr,
372 			    struct trace_array_cpu *data,
373 			    unsigned long ip,
374 			    unsigned long parent_ip,
375 			    unsigned long flags, int pc);
376 void tracing_sched_switch_trace(struct trace_array *tr,
377 				struct task_struct *prev,
378 				struct task_struct *next,
379 				unsigned long flags, int pc);
380 
381 void tracing_sched_wakeup_trace(struct trace_array *tr,
382 				struct task_struct *wakee,
383 				struct task_struct *cur,
384 				unsigned long flags, int pc);
385 void trace_function(struct trace_array *tr,
386 		    unsigned long ip,
387 		    unsigned long parent_ip,
388 		    unsigned long flags, int pc);
389 void trace_graph_function(struct trace_array *tr,
390 		    unsigned long ip,
391 		    unsigned long parent_ip,
392 		    unsigned long flags, int pc);
393 void trace_latency_header(struct seq_file *m);
394 void trace_default_header(struct seq_file *m);
395 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
396 int trace_empty(struct trace_iterator *iter);
397 
398 void trace_graph_return(struct ftrace_graph_ret *trace);
399 int trace_graph_entry(struct ftrace_graph_ent *trace);
400 void set_graph_array(struct trace_array *tr);
401 
402 void tracing_start_cmdline_record(void);
403 void tracing_stop_cmdline_record(void);
404 void tracing_sched_switch_assign_trace(struct trace_array *tr);
405 void tracing_stop_sched_switch_record(void);
406 void tracing_start_sched_switch_record(void);
407 int register_tracer(struct tracer *type);
408 int is_tracing_stopped(void);
409 
410 extern cpumask_var_t __read_mostly tracing_buffer_mask;
411 
412 #define for_each_tracing_cpu(cpu)	\
413 	for_each_cpu(cpu, tracing_buffer_mask)
414 
415 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
416 
417 extern unsigned long tracing_thresh;
418 
419 #ifdef CONFIG_TRACER_MAX_TRACE
420 extern unsigned long tracing_max_latency;
421 
422 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
423 void update_max_tr_single(struct trace_array *tr,
424 			  struct task_struct *tsk, int cpu);
425 #endif /* CONFIG_TRACER_MAX_TRACE */
426 
427 #ifdef CONFIG_STACKTRACE
428 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
429 			int skip, int pc);
430 
431 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
432 			     int skip, int pc, struct pt_regs *regs);
433 
434 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
435 			    int pc);
436 
437 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
438 		   int pc);
439 #else
440 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
441 				      unsigned long flags, int skip, int pc)
442 {
443 }
444 
445 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
446 					   unsigned long flags, int skip,
447 					   int pc, struct pt_regs *regs)
448 {
449 }
450 
451 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
452 					  unsigned long flags, int pc)
453 {
454 }
455 
456 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
457 				 int skip, int pc)
458 {
459 }
460 #endif /* CONFIG_STACKTRACE */
461 
462 extern cycle_t ftrace_now(int cpu);
463 
464 extern void trace_find_cmdline(int pid, char comm[]);
465 
466 #ifdef CONFIG_DYNAMIC_FTRACE
467 extern unsigned long ftrace_update_tot_cnt;
468 #endif
469 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
470 extern int DYN_FTRACE_TEST_NAME(void);
471 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
472 extern int DYN_FTRACE_TEST_NAME2(void);
473 
474 extern int ring_buffer_expanded;
475 extern bool tracing_selftest_disabled;
476 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
477 
478 #ifdef CONFIG_FTRACE_STARTUP_TEST
479 extern int trace_selftest_startup_function(struct tracer *trace,
480 					   struct trace_array *tr);
481 extern int trace_selftest_startup_function_graph(struct tracer *trace,
482 						 struct trace_array *tr);
483 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
484 					  struct trace_array *tr);
485 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
486 					     struct trace_array *tr);
487 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
488 						 struct trace_array *tr);
489 extern int trace_selftest_startup_wakeup(struct tracer *trace,
490 					 struct trace_array *tr);
491 extern int trace_selftest_startup_nop(struct tracer *trace,
492 					 struct trace_array *tr);
493 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
494 					       struct trace_array *tr);
495 extern int trace_selftest_startup_branch(struct tracer *trace,
496 					 struct trace_array *tr);
497 #endif /* CONFIG_FTRACE_STARTUP_TEST */
498 
499 extern void *head_page(struct trace_array_cpu *data);
500 extern unsigned long long ns2usecs(cycle_t nsec);
501 extern int
502 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
503 extern int
504 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
505 extern int
506 trace_array_vprintk(struct trace_array *tr,
507 		    unsigned long ip, const char *fmt, va_list args);
508 int trace_array_printk(struct trace_array *tr,
509 		       unsigned long ip, const char *fmt, ...);
510 void trace_printk_seq(struct trace_seq *s);
511 enum print_line_t print_trace_line(struct trace_iterator *iter);
512 
513 extern unsigned long trace_flags;
514 
515 extern int trace_clock_id;
516 
517 /* Standard output formatting function used for function return traces */
518 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
519 
520 /* Flag options */
521 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
522 #define TRACE_GRAPH_PRINT_CPU           0x2
523 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
524 #define TRACE_GRAPH_PRINT_PROC          0x8
525 #define TRACE_GRAPH_PRINT_DURATION      0x10
526 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
527 
528 extern enum print_line_t
529 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
530 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
531 extern enum print_line_t
532 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
533 extern void graph_trace_open(struct trace_iterator *iter);
534 extern void graph_trace_close(struct trace_iterator *iter);
535 extern int __trace_graph_entry(struct trace_array *tr,
536 			       struct ftrace_graph_ent *trace,
537 			       unsigned long flags, int pc);
538 extern void __trace_graph_return(struct trace_array *tr,
539 				 struct ftrace_graph_ret *trace,
540 				 unsigned long flags, int pc);
541 
542 
543 #ifdef CONFIG_DYNAMIC_FTRACE
544 /* TODO: make this variable */
545 #define FTRACE_GRAPH_MAX_FUNCS		32
546 extern int ftrace_graph_filter_enabled;
547 extern int ftrace_graph_count;
548 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
549 
550 static inline int ftrace_graph_addr(unsigned long addr)
551 {
552 	int i;
553 
554 	if (!ftrace_graph_filter_enabled)
555 		return 1;
556 
557 	for (i = 0; i < ftrace_graph_count; i++) {
558 		if (addr == ftrace_graph_funcs[i]) {
559 			/*
560 			 * If no irqs are to be traced, but a set_graph_function
561 			 * is set, and called by an interrupt handler, we still
562 			 * want to trace it.
563 			 */
564 			if (in_irq())
565 				trace_recursion_set(TRACE_IRQ_BIT);
566 			else
567 				trace_recursion_clear(TRACE_IRQ_BIT);
568 			return 1;
569 		}
570 	}
571 
572 	return 0;
573 }
574 #else
575 static inline int ftrace_graph_addr(unsigned long addr)
576 {
577 	return 1;
578 }
579 #endif /* CONFIG_DYNAMIC_FTRACE */
580 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
581 static inline enum print_line_t
582 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
583 {
584 	return TRACE_TYPE_UNHANDLED;
585 }
586 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
587 
588 extern struct list_head ftrace_pids;
589 
590 #ifdef CONFIG_FUNCTION_TRACER
591 static inline int ftrace_trace_task(struct task_struct *task)
592 {
593 	if (list_empty(&ftrace_pids))
594 		return 1;
595 
596 	return test_tsk_trace_trace(task);
597 }
598 extern int ftrace_is_dead(void);
599 #else
600 static inline int ftrace_trace_task(struct task_struct *task)
601 {
602 	return 1;
603 }
604 static inline int ftrace_is_dead(void) { return 0; }
605 #endif
606 
607 int ftrace_event_is_function(struct ftrace_event_call *call);
608 
609 /*
610  * struct trace_parser - servers for reading the user input separated by spaces
611  * @cont: set if the input is not complete - no final space char was found
612  * @buffer: holds the parsed user input
613  * @idx: user input length
614  * @size: buffer size
615  */
616 struct trace_parser {
617 	bool		cont;
618 	char		*buffer;
619 	unsigned	idx;
620 	unsigned	size;
621 };
622 
623 static inline bool trace_parser_loaded(struct trace_parser *parser)
624 {
625 	return (parser->idx != 0);
626 }
627 
628 static inline bool trace_parser_cont(struct trace_parser *parser)
629 {
630 	return parser->cont;
631 }
632 
633 static inline void trace_parser_clear(struct trace_parser *parser)
634 {
635 	parser->cont = false;
636 	parser->idx = 0;
637 }
638 
639 extern int trace_parser_get_init(struct trace_parser *parser, int size);
640 extern void trace_parser_put(struct trace_parser *parser);
641 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
642 	size_t cnt, loff_t *ppos);
643 
644 /*
645  * trace_iterator_flags is an enumeration that defines bit
646  * positions into trace_flags that controls the output.
647  *
648  * NOTE: These bits must match the trace_options array in
649  *       trace.c.
650  */
651 enum trace_iterator_flags {
652 	TRACE_ITER_PRINT_PARENT		= 0x01,
653 	TRACE_ITER_SYM_OFFSET		= 0x02,
654 	TRACE_ITER_SYM_ADDR		= 0x04,
655 	TRACE_ITER_VERBOSE		= 0x08,
656 	TRACE_ITER_RAW			= 0x10,
657 	TRACE_ITER_HEX			= 0x20,
658 	TRACE_ITER_BIN			= 0x40,
659 	TRACE_ITER_BLOCK		= 0x80,
660 	TRACE_ITER_STACKTRACE		= 0x100,
661 	TRACE_ITER_PRINTK		= 0x200,
662 	TRACE_ITER_PREEMPTONLY		= 0x400,
663 	TRACE_ITER_BRANCH		= 0x800,
664 	TRACE_ITER_ANNOTATE		= 0x1000,
665 	TRACE_ITER_USERSTACKTRACE       = 0x2000,
666 	TRACE_ITER_SYM_USEROBJ          = 0x4000,
667 	TRACE_ITER_PRINTK_MSGONLY	= 0x8000,
668 	TRACE_ITER_CONTEXT_INFO		= 0x10000, /* Print pid/cpu/time */
669 	TRACE_ITER_LATENCY_FMT		= 0x20000,
670 	TRACE_ITER_SLEEP_TIME		= 0x40000,
671 	TRACE_ITER_GRAPH_TIME		= 0x80000,
672 	TRACE_ITER_RECORD_CMD		= 0x100000,
673 	TRACE_ITER_OVERWRITE		= 0x200000,
674 	TRACE_ITER_STOP_ON_FREE		= 0x400000,
675 	TRACE_ITER_IRQ_INFO		= 0x800000,
676 	TRACE_ITER_MARKERS		= 0x1000000,
677 };
678 
679 /*
680  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
681  * control the output of kernel symbols.
682  */
683 #define TRACE_ITER_SYM_MASK \
684 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
685 
686 extern struct tracer nop_trace;
687 
688 #ifdef CONFIG_BRANCH_TRACER
689 extern int enable_branch_tracing(struct trace_array *tr);
690 extern void disable_branch_tracing(void);
691 static inline int trace_branch_enable(struct trace_array *tr)
692 {
693 	if (trace_flags & TRACE_ITER_BRANCH)
694 		return enable_branch_tracing(tr);
695 	return 0;
696 }
697 static inline void trace_branch_disable(void)
698 {
699 	/* due to races, always disable */
700 	disable_branch_tracing();
701 }
702 #else
703 static inline int trace_branch_enable(struct trace_array *tr)
704 {
705 	return 0;
706 }
707 static inline void trace_branch_disable(void)
708 {
709 }
710 #endif /* CONFIG_BRANCH_TRACER */
711 
712 /* set ring buffers to default size if not already done so */
713 int tracing_update_buffers(void);
714 
715 /* trace event type bit fields, not numeric */
716 enum {
717 	TRACE_EVENT_TYPE_PRINTF		= 1,
718 	TRACE_EVENT_TYPE_RAW		= 2,
719 };
720 
721 struct ftrace_event_field {
722 	struct list_head	link;
723 	char			*name;
724 	char			*type;
725 	int			filter_type;
726 	int			offset;
727 	int			size;
728 	int			is_signed;
729 };
730 
731 struct event_filter {
732 	int			n_preds;	/* Number assigned */
733 	int			a_preds;	/* allocated */
734 	struct filter_pred	*preds;
735 	struct filter_pred	*root;
736 	char			*filter_string;
737 };
738 
739 struct event_subsystem {
740 	struct list_head	list;
741 	const char		*name;
742 	struct dentry		*entry;
743 	struct event_filter	*filter;
744 	int			nr_events;
745 	int			ref_count;
746 };
747 
748 #define FILTER_PRED_INVALID	((unsigned short)-1)
749 #define FILTER_PRED_IS_RIGHT	(1 << 15)
750 #define FILTER_PRED_FOLD	(1 << 15)
751 
752 /*
753  * The max preds is the size of unsigned short with
754  * two flags at the MSBs. One bit is used for both the IS_RIGHT
755  * and FOLD flags. The other is reserved.
756  *
757  * 2^14 preds is way more than enough.
758  */
759 #define MAX_FILTER_PRED		16384
760 
761 struct filter_pred;
762 struct regex;
763 
764 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
765 
766 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
767 
768 enum regex_type {
769 	MATCH_FULL = 0,
770 	MATCH_FRONT_ONLY,
771 	MATCH_MIDDLE_ONLY,
772 	MATCH_END_ONLY,
773 };
774 
775 struct regex {
776 	char			pattern[MAX_FILTER_STR_VAL];
777 	int			len;
778 	int			field_len;
779 	regex_match_func	match;
780 };
781 
782 struct filter_pred {
783 	filter_pred_fn_t 	fn;
784 	u64 			val;
785 	struct regex		regex;
786 	unsigned short		*ops;
787 	struct ftrace_event_field *field;
788 	int 			offset;
789 	int 			not;
790 	int 			op;
791 	unsigned short		index;
792 	unsigned short		parent;
793 	unsigned short		left;
794 	unsigned short		right;
795 };
796 
797 extern struct list_head ftrace_common_fields;
798 
799 extern enum regex_type
800 filter_parse_regex(char *buff, int len, char **search, int *not);
801 extern void print_event_filter(struct ftrace_event_call *call,
802 			       struct trace_seq *s);
803 extern int apply_event_filter(struct ftrace_event_call *call,
804 			      char *filter_string);
805 extern int apply_subsystem_event_filter(struct event_subsystem *system,
806 					char *filter_string);
807 extern void print_subsystem_event_filter(struct event_subsystem *system,
808 					 struct trace_seq *s);
809 extern int filter_assign_type(const char *type);
810 
811 struct list_head *
812 trace_get_fields(struct ftrace_event_call *event_call);
813 
814 static inline int
815 filter_check_discard(struct ftrace_event_call *call, void *rec,
816 		     struct ring_buffer *buffer,
817 		     struct ring_buffer_event *event)
818 {
819 	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
820 	    !filter_match_preds(call->filter, rec)) {
821 		ring_buffer_discard_commit(buffer, event);
822 		return 1;
823 	}
824 
825 	return 0;
826 }
827 
828 extern void trace_event_enable_cmd_record(bool enable);
829 
830 extern struct mutex event_mutex;
831 extern struct list_head ftrace_events;
832 
833 extern const char *__start___trace_bprintk_fmt[];
834 extern const char *__stop___trace_bprintk_fmt[];
835 
836 void trace_printk_init_buffers(void);
837 void trace_printk_start_comm(void);
838 
839 #undef FTRACE_ENTRY
840 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
841 	extern struct ftrace_event_call					\
842 	__attribute__((__aligned__(4))) event_##call;
843 #undef FTRACE_ENTRY_DUP
844 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
845 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
846 		     filter)
847 #include "trace_entries.h"
848 
849 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
850 int perf_ftrace_event_register(struct ftrace_event_call *call,
851 			       enum trace_reg type, void *data);
852 #else
853 #define perf_ftrace_event_register NULL
854 #endif
855 
856 #endif /* _LINUX_KERNEL_TRACE_H */
857