xref: /openbmc/linux/kernel/trace/trace.h (revision 95c96174)
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 	int			buffer_disabled;
158 	cycle_t			time_start;
159 	struct task_struct	*waiter;
160 	struct trace_array_cpu	*data[NR_CPUS];
161 };
162 
163 #define FTRACE_CMP_TYPE(var, type) \
164 	__builtin_types_compatible_p(typeof(var), type *)
165 
166 #undef IF_ASSIGN
167 #define IF_ASSIGN(var, entry, etype, id)		\
168 	if (FTRACE_CMP_TYPE(var, etype)) {		\
169 		var = (typeof(var))(entry);		\
170 		WARN_ON(id && (entry)->type != id);	\
171 		break;					\
172 	}
173 
174 /* Will cause compile errors if type is not found. */
175 extern void __ftrace_bad_type(void);
176 
177 /*
178  * The trace_assign_type is a verifier that the entry type is
179  * the same as the type being assigned. To add new types simply
180  * add a line with the following format:
181  *
182  * IF_ASSIGN(var, ent, type, id);
183  *
184  *  Where "type" is the trace type that includes the trace_entry
185  *  as the "ent" item. And "id" is the trace identifier that is
186  *  used in the trace_type enum.
187  *
188  *  If the type can have more than one id, then use zero.
189  */
190 #define trace_assign_type(var, ent)					\
191 	do {								\
192 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
193 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
194 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
195 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
196 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
197 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
198 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
199 			  TRACE_MMIO_RW);				\
200 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
201 			  TRACE_MMIO_MAP);				\
202 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
203 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
204 			  TRACE_GRAPH_ENT);		\
205 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
206 			  TRACE_GRAPH_RET);		\
207 		__ftrace_bad_type();					\
208 	} while (0)
209 
210 /*
211  * An option specific to a tracer. This is a boolean value.
212  * The bit is the bit index that sets its value on the
213  * flags value in struct tracer_flags.
214  */
215 struct tracer_opt {
216 	const char	*name; /* Will appear on the trace_options file */
217 	u32		bit; /* Mask assigned in val field in tracer_flags */
218 };
219 
220 /*
221  * The set of specific options for a tracer. Your tracer
222  * have to set the initial value of the flags val.
223  */
224 struct tracer_flags {
225 	u32			val;
226 	struct tracer_opt	*opts;
227 };
228 
229 /* Makes more easy to define a tracer opt */
230 #define TRACER_OPT(s, b)	.name = #s, .bit = b
231 
232 
233 /**
234  * struct tracer - a specific tracer and its callbacks to interact with debugfs
235  * @name: the name chosen to select it on the available_tracers file
236  * @init: called when one switches to this tracer (echo name > current_tracer)
237  * @reset: called when one switches to another tracer
238  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
239  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
240  * @open: called when the trace file is opened
241  * @pipe_open: called when the trace_pipe file is opened
242  * @wait_pipe: override how the user waits for traces on trace_pipe
243  * @close: called when the trace file is released
244  * @pipe_close: called when the trace_pipe file is released
245  * @read: override the default read callback on trace_pipe
246  * @splice_read: override the default splice_read callback on trace_pipe
247  * @selftest: selftest to run on boot (see trace_selftest.c)
248  * @print_headers: override the first lines that describe your columns
249  * @print_line: callback that prints a trace
250  * @set_flag: signals one of your private flags changed (trace_options file)
251  * @flags: your private flags
252  */
253 struct tracer {
254 	const char		*name;
255 	int			(*init)(struct trace_array *tr);
256 	void			(*reset)(struct trace_array *tr);
257 	void			(*start)(struct trace_array *tr);
258 	void			(*stop)(struct trace_array *tr);
259 	void			(*open)(struct trace_iterator *iter);
260 	void			(*pipe_open)(struct trace_iterator *iter);
261 	void			(*wait_pipe)(struct trace_iterator *iter);
262 	void			(*close)(struct trace_iterator *iter);
263 	void			(*pipe_close)(struct trace_iterator *iter);
264 	ssize_t			(*read)(struct trace_iterator *iter,
265 					struct file *filp, char __user *ubuf,
266 					size_t cnt, loff_t *ppos);
267 	ssize_t			(*splice_read)(struct trace_iterator *iter,
268 					       struct file *filp,
269 					       loff_t *ppos,
270 					       struct pipe_inode_info *pipe,
271 					       size_t len,
272 					       unsigned int flags);
273 #ifdef CONFIG_FTRACE_STARTUP_TEST
274 	int			(*selftest)(struct tracer *trace,
275 					    struct trace_array *tr);
276 #endif
277 	void			(*print_header)(struct seq_file *m);
278 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
279 	/* If you handled the flag setting, return 0 */
280 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
281 	struct tracer		*next;
282 	struct tracer_flags	*flags;
283 	int			print_max;
284 	int			use_max_tr;
285 };
286 
287 
288 /* Only current can touch trace_recursion */
289 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
290 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
291 
292 /* Ring buffer has the 10 LSB bits to count */
293 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
294 
295 /* for function tracing recursion */
296 #define TRACE_INTERNAL_BIT		(1<<11)
297 #define TRACE_GLOBAL_BIT		(1<<12)
298 #define TRACE_CONTROL_BIT		(1<<13)
299 
300 /*
301  * Abuse of the trace_recursion.
302  * As we need a way to maintain state if we are tracing the function
303  * graph in irq because we want to trace a particular function that
304  * was called in irq context but we have irq tracing off. Since this
305  * can only be modified by current, we can reuse trace_recursion.
306  */
307 #define TRACE_IRQ_BIT			(1<<13)
308 
309 #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (bit); } while (0)
310 #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(bit); } while (0)
311 #define trace_recursion_test(bit)	((current)->trace_recursion & (bit))
312 
313 #define TRACE_PIPE_ALL_CPU	-1
314 
315 int tracer_init(struct tracer *t, struct trace_array *tr);
316 int tracing_is_enabled(void);
317 void trace_wake_up(void);
318 void tracing_reset(struct trace_array *tr, int cpu);
319 void tracing_reset_online_cpus(struct trace_array *tr);
320 void tracing_reset_current(int cpu);
321 void tracing_reset_current_online_cpus(void);
322 int tracing_open_generic(struct inode *inode, struct file *filp);
323 struct dentry *trace_create_file(const char *name,
324 				 umode_t mode,
325 				 struct dentry *parent,
326 				 void *data,
327 				 const struct file_operations *fops);
328 
329 struct dentry *tracing_init_dentry(void);
330 
331 struct ring_buffer_event;
332 
333 struct ring_buffer_event *
334 trace_buffer_lock_reserve(struct ring_buffer *buffer,
335 			  int type,
336 			  unsigned long len,
337 			  unsigned long flags,
338 			  int pc);
339 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
340 				struct ring_buffer_event *event,
341 				unsigned long flags, int pc);
342 
343 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
344 						struct trace_array_cpu *data);
345 
346 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
347 					  int *ent_cpu, u64 *ent_ts);
348 
349 int trace_empty(struct trace_iterator *iter);
350 
351 void *trace_find_next_entry_inc(struct trace_iterator *iter);
352 
353 void trace_init_global_iter(struct trace_iterator *iter);
354 
355 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
356 
357 void default_wait_pipe(struct trace_iterator *iter);
358 void poll_wait_pipe(struct trace_iterator *iter);
359 
360 void ftrace(struct trace_array *tr,
361 			    struct trace_array_cpu *data,
362 			    unsigned long ip,
363 			    unsigned long parent_ip,
364 			    unsigned long flags, int pc);
365 void tracing_sched_switch_trace(struct trace_array *tr,
366 				struct task_struct *prev,
367 				struct task_struct *next,
368 				unsigned long flags, int pc);
369 
370 void tracing_sched_wakeup_trace(struct trace_array *tr,
371 				struct task_struct *wakee,
372 				struct task_struct *cur,
373 				unsigned long flags, int pc);
374 void trace_function(struct trace_array *tr,
375 		    unsigned long ip,
376 		    unsigned long parent_ip,
377 		    unsigned long flags, int pc);
378 void trace_graph_function(struct trace_array *tr,
379 		    unsigned long ip,
380 		    unsigned long parent_ip,
381 		    unsigned long flags, int pc);
382 void trace_latency_header(struct seq_file *m);
383 void trace_default_header(struct seq_file *m);
384 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
385 int trace_empty(struct trace_iterator *iter);
386 
387 void trace_graph_return(struct ftrace_graph_ret *trace);
388 int trace_graph_entry(struct ftrace_graph_ent *trace);
389 void set_graph_array(struct trace_array *tr);
390 
391 void tracing_start_cmdline_record(void);
392 void tracing_stop_cmdline_record(void);
393 void tracing_sched_switch_assign_trace(struct trace_array *tr);
394 void tracing_stop_sched_switch_record(void);
395 void tracing_start_sched_switch_record(void);
396 int register_tracer(struct tracer *type);
397 void unregister_tracer(struct tracer *type);
398 int is_tracing_stopped(void);
399 enum trace_file_type {
400 	TRACE_FILE_LAT_FMT	= 1,
401 	TRACE_FILE_ANNOTATE	= 2,
402 };
403 
404 extern cpumask_var_t __read_mostly tracing_buffer_mask;
405 
406 #define for_each_tracing_cpu(cpu)	\
407 	for_each_cpu(cpu, tracing_buffer_mask)
408 
409 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
410 
411 extern unsigned long tracing_thresh;
412 
413 #ifdef CONFIG_TRACER_MAX_TRACE
414 extern unsigned long tracing_max_latency;
415 
416 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
417 void update_max_tr_single(struct trace_array *tr,
418 			  struct task_struct *tsk, int cpu);
419 #endif /* CONFIG_TRACER_MAX_TRACE */
420 
421 #ifdef CONFIG_STACKTRACE
422 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
423 			int skip, int pc);
424 
425 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
426 			     int skip, int pc, struct pt_regs *regs);
427 
428 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
429 			    int pc);
430 
431 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
432 		   int pc);
433 #else
434 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
435 				      unsigned long flags, int skip, int pc)
436 {
437 }
438 
439 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
440 					   unsigned long flags, int skip,
441 					   int pc, struct pt_regs *regs)
442 {
443 }
444 
445 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
446 					  unsigned long flags, int pc)
447 {
448 }
449 
450 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
451 				 int skip, int pc)
452 {
453 }
454 #endif /* CONFIG_STACKTRACE */
455 
456 extern cycle_t ftrace_now(int cpu);
457 
458 extern void trace_find_cmdline(int pid, char comm[]);
459 
460 #ifdef CONFIG_DYNAMIC_FTRACE
461 extern unsigned long ftrace_update_tot_cnt;
462 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
463 extern int DYN_FTRACE_TEST_NAME(void);
464 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
465 extern int DYN_FTRACE_TEST_NAME2(void);
466 #endif
467 
468 extern int ring_buffer_expanded;
469 extern bool tracing_selftest_disabled;
470 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
471 
472 #ifdef CONFIG_FTRACE_STARTUP_TEST
473 extern int trace_selftest_startup_function(struct tracer *trace,
474 					   struct trace_array *tr);
475 extern int trace_selftest_startup_function_graph(struct tracer *trace,
476 						 struct trace_array *tr);
477 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
478 					  struct trace_array *tr);
479 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
480 					     struct trace_array *tr);
481 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
482 						 struct trace_array *tr);
483 extern int trace_selftest_startup_wakeup(struct tracer *trace,
484 					 struct trace_array *tr);
485 extern int trace_selftest_startup_nop(struct tracer *trace,
486 					 struct trace_array *tr);
487 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
488 					       struct trace_array *tr);
489 extern int trace_selftest_startup_branch(struct tracer *trace,
490 					 struct trace_array *tr);
491 #endif /* CONFIG_FTRACE_STARTUP_TEST */
492 
493 extern void *head_page(struct trace_array_cpu *data);
494 extern unsigned long long ns2usecs(cycle_t nsec);
495 extern int
496 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
497 extern int
498 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
499 extern int
500 trace_array_vprintk(struct trace_array *tr,
501 		    unsigned long ip, const char *fmt, va_list args);
502 int trace_array_printk(struct trace_array *tr,
503 		       unsigned long ip, const char *fmt, ...);
504 void trace_printk_seq(struct trace_seq *s);
505 enum print_line_t print_trace_line(struct trace_iterator *iter);
506 
507 extern unsigned long trace_flags;
508 
509 extern int trace_clock_id;
510 
511 /* Standard output formatting function used for function return traces */
512 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
513 
514 /* Flag options */
515 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
516 #define TRACE_GRAPH_PRINT_CPU           0x2
517 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
518 #define TRACE_GRAPH_PRINT_PROC          0x8
519 #define TRACE_GRAPH_PRINT_DURATION      0x10
520 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
521 
522 extern enum print_line_t
523 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
524 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
525 extern enum print_line_t
526 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
527 extern void graph_trace_open(struct trace_iterator *iter);
528 extern void graph_trace_close(struct trace_iterator *iter);
529 extern int __trace_graph_entry(struct trace_array *tr,
530 			       struct ftrace_graph_ent *trace,
531 			       unsigned long flags, int pc);
532 extern void __trace_graph_return(struct trace_array *tr,
533 				 struct ftrace_graph_ret *trace,
534 				 unsigned long flags, int pc);
535 
536 
537 #ifdef CONFIG_DYNAMIC_FTRACE
538 /* TODO: make this variable */
539 #define FTRACE_GRAPH_MAX_FUNCS		32
540 extern int ftrace_graph_filter_enabled;
541 extern int ftrace_graph_count;
542 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
543 
544 static inline int ftrace_graph_addr(unsigned long addr)
545 {
546 	int i;
547 
548 	if (!ftrace_graph_filter_enabled)
549 		return 1;
550 
551 	for (i = 0; i < ftrace_graph_count; i++) {
552 		if (addr == ftrace_graph_funcs[i]) {
553 			/*
554 			 * If no irqs are to be traced, but a set_graph_function
555 			 * is set, and called by an interrupt handler, we still
556 			 * want to trace it.
557 			 */
558 			if (in_irq())
559 				trace_recursion_set(TRACE_IRQ_BIT);
560 			else
561 				trace_recursion_clear(TRACE_IRQ_BIT);
562 			return 1;
563 		}
564 	}
565 
566 	return 0;
567 }
568 #else
569 static inline int ftrace_graph_addr(unsigned long addr)
570 {
571 	return 1;
572 }
573 #endif /* CONFIG_DYNAMIC_FTRACE */
574 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
575 static inline enum print_line_t
576 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
577 {
578 	return TRACE_TYPE_UNHANDLED;
579 }
580 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
581 
582 extern struct list_head ftrace_pids;
583 
584 #ifdef CONFIG_FUNCTION_TRACER
585 static inline int ftrace_trace_task(struct task_struct *task)
586 {
587 	if (list_empty(&ftrace_pids))
588 		return 1;
589 
590 	return test_tsk_trace_trace(task);
591 }
592 extern int ftrace_is_dead(void);
593 #else
594 static inline int ftrace_trace_task(struct task_struct *task)
595 {
596 	return 1;
597 }
598 static inline int ftrace_is_dead(void) { return 0; }
599 #endif
600 
601 int ftrace_event_is_function(struct ftrace_event_call *call);
602 
603 /*
604  * struct trace_parser - servers for reading the user input separated by spaces
605  * @cont: set if the input is not complete - no final space char was found
606  * @buffer: holds the parsed user input
607  * @idx: user input length
608  * @size: buffer size
609  */
610 struct trace_parser {
611 	bool		cont;
612 	char		*buffer;
613 	unsigned	idx;
614 	unsigned	size;
615 };
616 
617 static inline bool trace_parser_loaded(struct trace_parser *parser)
618 {
619 	return (parser->idx != 0);
620 }
621 
622 static inline bool trace_parser_cont(struct trace_parser *parser)
623 {
624 	return parser->cont;
625 }
626 
627 static inline void trace_parser_clear(struct trace_parser *parser)
628 {
629 	parser->cont = false;
630 	parser->idx = 0;
631 }
632 
633 extern int trace_parser_get_init(struct trace_parser *parser, int size);
634 extern void trace_parser_put(struct trace_parser *parser);
635 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
636 	size_t cnt, loff_t *ppos);
637 
638 /*
639  * trace_iterator_flags is an enumeration that defines bit
640  * positions into trace_flags that controls the output.
641  *
642  * NOTE: These bits must match the trace_options array in
643  *       trace.c.
644  */
645 enum trace_iterator_flags {
646 	TRACE_ITER_PRINT_PARENT		= 0x01,
647 	TRACE_ITER_SYM_OFFSET		= 0x02,
648 	TRACE_ITER_SYM_ADDR		= 0x04,
649 	TRACE_ITER_VERBOSE		= 0x08,
650 	TRACE_ITER_RAW			= 0x10,
651 	TRACE_ITER_HEX			= 0x20,
652 	TRACE_ITER_BIN			= 0x40,
653 	TRACE_ITER_BLOCK		= 0x80,
654 	TRACE_ITER_STACKTRACE		= 0x100,
655 	TRACE_ITER_PRINTK		= 0x200,
656 	TRACE_ITER_PREEMPTONLY		= 0x400,
657 	TRACE_ITER_BRANCH		= 0x800,
658 	TRACE_ITER_ANNOTATE		= 0x1000,
659 	TRACE_ITER_USERSTACKTRACE       = 0x2000,
660 	TRACE_ITER_SYM_USEROBJ          = 0x4000,
661 	TRACE_ITER_PRINTK_MSGONLY	= 0x8000,
662 	TRACE_ITER_CONTEXT_INFO		= 0x10000, /* Print pid/cpu/time */
663 	TRACE_ITER_LATENCY_FMT		= 0x20000,
664 	TRACE_ITER_SLEEP_TIME		= 0x40000,
665 	TRACE_ITER_GRAPH_TIME		= 0x80000,
666 	TRACE_ITER_RECORD_CMD		= 0x100000,
667 	TRACE_ITER_OVERWRITE		= 0x200000,
668 	TRACE_ITER_STOP_ON_FREE		= 0x400000,
669 	TRACE_ITER_IRQ_INFO		= 0x800000,
670 };
671 
672 /*
673  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
674  * control the output of kernel symbols.
675  */
676 #define TRACE_ITER_SYM_MASK \
677 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
678 
679 extern struct tracer nop_trace;
680 
681 #ifdef CONFIG_BRANCH_TRACER
682 extern int enable_branch_tracing(struct trace_array *tr);
683 extern void disable_branch_tracing(void);
684 static inline int trace_branch_enable(struct trace_array *tr)
685 {
686 	if (trace_flags & TRACE_ITER_BRANCH)
687 		return enable_branch_tracing(tr);
688 	return 0;
689 }
690 static inline void trace_branch_disable(void)
691 {
692 	/* due to races, always disable */
693 	disable_branch_tracing();
694 }
695 #else
696 static inline int trace_branch_enable(struct trace_array *tr)
697 {
698 	return 0;
699 }
700 static inline void trace_branch_disable(void)
701 {
702 }
703 #endif /* CONFIG_BRANCH_TRACER */
704 
705 /* set ring buffers to default size if not already done so */
706 int tracing_update_buffers(void);
707 
708 /* trace event type bit fields, not numeric */
709 enum {
710 	TRACE_EVENT_TYPE_PRINTF		= 1,
711 	TRACE_EVENT_TYPE_RAW		= 2,
712 };
713 
714 struct ftrace_event_field {
715 	struct list_head	link;
716 	char			*name;
717 	char			*type;
718 	int			filter_type;
719 	int			offset;
720 	int			size;
721 	int			is_signed;
722 };
723 
724 struct event_filter {
725 	int			n_preds;	/* Number assigned */
726 	int			a_preds;	/* allocated */
727 	struct filter_pred	*preds;
728 	struct filter_pred	*root;
729 	char			*filter_string;
730 };
731 
732 struct event_subsystem {
733 	struct list_head	list;
734 	const char		*name;
735 	struct dentry		*entry;
736 	struct event_filter	*filter;
737 	int			nr_events;
738 	int			ref_count;
739 };
740 
741 #define FILTER_PRED_INVALID	((unsigned short)-1)
742 #define FILTER_PRED_IS_RIGHT	(1 << 15)
743 #define FILTER_PRED_FOLD	(1 << 15)
744 
745 /*
746  * The max preds is the size of unsigned short with
747  * two flags at the MSBs. One bit is used for both the IS_RIGHT
748  * and FOLD flags. The other is reserved.
749  *
750  * 2^14 preds is way more than enough.
751  */
752 #define MAX_FILTER_PRED		16384
753 
754 struct filter_pred;
755 struct regex;
756 
757 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
758 
759 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
760 
761 enum regex_type {
762 	MATCH_FULL = 0,
763 	MATCH_FRONT_ONLY,
764 	MATCH_MIDDLE_ONLY,
765 	MATCH_END_ONLY,
766 };
767 
768 struct regex {
769 	char			pattern[MAX_FILTER_STR_VAL];
770 	int			len;
771 	int			field_len;
772 	regex_match_func	match;
773 };
774 
775 struct filter_pred {
776 	filter_pred_fn_t 	fn;
777 	u64 			val;
778 	struct regex		regex;
779 	unsigned short		*ops;
780 	struct ftrace_event_field *field;
781 	int 			offset;
782 	int 			not;
783 	int 			op;
784 	unsigned short		index;
785 	unsigned short		parent;
786 	unsigned short		left;
787 	unsigned short		right;
788 };
789 
790 extern struct list_head ftrace_common_fields;
791 
792 extern enum regex_type
793 filter_parse_regex(char *buff, int len, char **search, int *not);
794 extern void print_event_filter(struct ftrace_event_call *call,
795 			       struct trace_seq *s);
796 extern int apply_event_filter(struct ftrace_event_call *call,
797 			      char *filter_string);
798 extern int apply_subsystem_event_filter(struct event_subsystem *system,
799 					char *filter_string);
800 extern void print_subsystem_event_filter(struct event_subsystem *system,
801 					 struct trace_seq *s);
802 extern int filter_assign_type(const char *type);
803 
804 struct list_head *
805 trace_get_fields(struct ftrace_event_call *event_call);
806 
807 static inline int
808 filter_check_discard(struct ftrace_event_call *call, void *rec,
809 		     struct ring_buffer *buffer,
810 		     struct ring_buffer_event *event)
811 {
812 	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
813 	    !filter_match_preds(call->filter, rec)) {
814 		ring_buffer_discard_commit(buffer, event);
815 		return 1;
816 	}
817 
818 	return 0;
819 }
820 
821 extern void trace_event_enable_cmd_record(bool enable);
822 
823 extern struct mutex event_mutex;
824 extern struct list_head ftrace_events;
825 
826 extern const char *__start___trace_bprintk_fmt[];
827 extern const char *__stop___trace_bprintk_fmt[];
828 
829 #undef FTRACE_ENTRY
830 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
831 	extern struct ftrace_event_call					\
832 	__attribute__((__aligned__(4))) event_##call;
833 #undef FTRACE_ENTRY_DUP
834 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
835 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
836 		     filter)
837 #include "trace_entries.h"
838 
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 
846 #endif /* _LINUX_KERNEL_TRACE_H */
847