xref: /openbmc/linux/kernel/trace/trace.h (revision 81d67439)
1 #ifndef _LINUX_KERNEL_TRACE_H
2 #define _LINUX_KERNEL_TRACE_H
3 
4 #include <linux/fs.h>
5 #include <asm/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)	\
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)
70 
71 #include "trace_entries.h"
72 
73 /*
74  * syscalls are special, and need special handling, this is why
75  * they are not included in trace_entries.h
76  */
77 struct syscall_trace_enter {
78 	struct trace_entry	ent;
79 	int			nr;
80 	unsigned long		args[];
81 };
82 
83 struct syscall_trace_exit {
84 	struct trace_entry	ent;
85 	int			nr;
86 	long			ret;
87 };
88 
89 struct kprobe_trace_entry_head {
90 	struct trace_entry	ent;
91 	unsigned long		ip;
92 };
93 
94 struct kretprobe_trace_entry_head {
95 	struct trace_entry	ent;
96 	unsigned long		func;
97 	unsigned long		ret_ip;
98 };
99 
100 /*
101  * trace_flag_type is an enumeration that holds different
102  * states when a trace occurs. These are:
103  *  IRQS_OFF		- interrupts were disabled
104  *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
105  *  NEED_RESCHED	- reschedule is requested
106  *  HARDIRQ		- inside an interrupt handler
107  *  SOFTIRQ		- inside a softirq handler
108  */
109 enum trace_flag_type {
110 	TRACE_FLAG_IRQS_OFF		= 0x01,
111 	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
112 	TRACE_FLAG_NEED_RESCHED		= 0x04,
113 	TRACE_FLAG_HARDIRQ		= 0x08,
114 	TRACE_FLAG_SOFTIRQ		= 0x10,
115 };
116 
117 #define TRACE_BUF_SIZE		1024
118 
119 /*
120  * The CPU trace array - it consists of thousands of trace entries
121  * plus some other descriptor data: (for example which task started
122  * the trace, etc.)
123  */
124 struct trace_array_cpu {
125 	atomic_t		disabled;
126 	void			*buffer_page;	/* ring buffer spare */
127 
128 	unsigned long		saved_latency;
129 	unsigned long		critical_start;
130 	unsigned long		critical_end;
131 	unsigned long		critical_sequence;
132 	unsigned long		nice;
133 	unsigned long		policy;
134 	unsigned long		rt_priority;
135 	unsigned long		skipped_entries;
136 	cycle_t			preempt_timestamp;
137 	pid_t			pid;
138 	uid_t			uid;
139 	char			comm[TASK_COMM_LEN];
140 };
141 
142 /*
143  * The trace array - an array of per-CPU trace arrays. This is the
144  * highest level data structure that individual tracers deal with.
145  * They have on/off state as well:
146  */
147 struct trace_array {
148 	struct ring_buffer	*buffer;
149 	unsigned long		entries;
150 	int			cpu;
151 	cycle_t			time_start;
152 	struct task_struct	*waiter;
153 	struct trace_array_cpu	*data[NR_CPUS];
154 };
155 
156 #define FTRACE_CMP_TYPE(var, type) \
157 	__builtin_types_compatible_p(typeof(var), type *)
158 
159 #undef IF_ASSIGN
160 #define IF_ASSIGN(var, entry, etype, id)		\
161 	if (FTRACE_CMP_TYPE(var, etype)) {		\
162 		var = (typeof(var))(entry);		\
163 		WARN_ON(id && (entry)->type != id);	\
164 		break;					\
165 	}
166 
167 /* Will cause compile errors if type is not found. */
168 extern void __ftrace_bad_type(void);
169 
170 /*
171  * The trace_assign_type is a verifier that the entry type is
172  * the same as the type being assigned. To add new types simply
173  * add a line with the following format:
174  *
175  * IF_ASSIGN(var, ent, type, id);
176  *
177  *  Where "type" is the trace type that includes the trace_entry
178  *  as the "ent" item. And "id" is the trace identifier that is
179  *  used in the trace_type enum.
180  *
181  *  If the type can have more than one id, then use zero.
182  */
183 #define trace_assign_type(var, ent)					\
184 	do {								\
185 		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
186 		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
187 		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
188 		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
189 		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
190 		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
191 		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
192 			  TRACE_MMIO_RW);				\
193 		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
194 			  TRACE_MMIO_MAP);				\
195 		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
196 		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
197 			  TRACE_GRAPH_ENT);		\
198 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
199 			  TRACE_GRAPH_RET);		\
200 		__ftrace_bad_type();					\
201 	} while (0)
202 
203 /*
204  * An option specific to a tracer. This is a boolean value.
205  * The bit is the bit index that sets its value on the
206  * flags value in struct tracer_flags.
207  */
208 struct tracer_opt {
209 	const char	*name; /* Will appear on the trace_options file */
210 	u32		bit; /* Mask assigned in val field in tracer_flags */
211 };
212 
213 /*
214  * The set of specific options for a tracer. Your tracer
215  * have to set the initial value of the flags val.
216  */
217 struct tracer_flags {
218 	u32			val;
219 	struct tracer_opt	*opts;
220 };
221 
222 /* Makes more easy to define a tracer opt */
223 #define TRACER_OPT(s, b)	.name = #s, .bit = b
224 
225 
226 /**
227  * struct tracer - a specific tracer and its callbacks to interact with debugfs
228  * @name: the name chosen to select it on the available_tracers file
229  * @init: called when one switches to this tracer (echo name > current_tracer)
230  * @reset: called when one switches to another tracer
231  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
232  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
233  * @open: called when the trace file is opened
234  * @pipe_open: called when the trace_pipe file is opened
235  * @wait_pipe: override how the user waits for traces on trace_pipe
236  * @close: called when the trace file is released
237  * @pipe_close: called when the trace_pipe file is released
238  * @read: override the default read callback on trace_pipe
239  * @splice_read: override the default splice_read callback on trace_pipe
240  * @selftest: selftest to run on boot (see trace_selftest.c)
241  * @print_headers: override the first lines that describe your columns
242  * @print_line: callback that prints a trace
243  * @set_flag: signals one of your private flags changed (trace_options file)
244  * @flags: your private flags
245  */
246 struct tracer {
247 	const char		*name;
248 	int			(*init)(struct trace_array *tr);
249 	void			(*reset)(struct trace_array *tr);
250 	void			(*start)(struct trace_array *tr);
251 	void			(*stop)(struct trace_array *tr);
252 	void			(*open)(struct trace_iterator *iter);
253 	void			(*pipe_open)(struct trace_iterator *iter);
254 	void			(*wait_pipe)(struct trace_iterator *iter);
255 	void			(*close)(struct trace_iterator *iter);
256 	void			(*pipe_close)(struct trace_iterator *iter);
257 	ssize_t			(*read)(struct trace_iterator *iter,
258 					struct file *filp, char __user *ubuf,
259 					size_t cnt, loff_t *ppos);
260 	ssize_t			(*splice_read)(struct trace_iterator *iter,
261 					       struct file *filp,
262 					       loff_t *ppos,
263 					       struct pipe_inode_info *pipe,
264 					       size_t len,
265 					       unsigned int flags);
266 #ifdef CONFIG_FTRACE_STARTUP_TEST
267 	int			(*selftest)(struct tracer *trace,
268 					    struct trace_array *tr);
269 #endif
270 	void			(*print_header)(struct seq_file *m);
271 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
272 	/* If you handled the flag setting, return 0 */
273 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
274 	struct tracer		*next;
275 	struct tracer_flags	*flags;
276 	int			print_max;
277 	int			use_max_tr;
278 };
279 
280 
281 /* Only current can touch trace_recursion */
282 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
283 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
284 
285 /* Ring buffer has the 10 LSB bits to count */
286 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
287 
288 /* for function tracing recursion */
289 #define TRACE_INTERNAL_BIT		(1<<11)
290 #define TRACE_GLOBAL_BIT		(1<<12)
291 /*
292  * Abuse of the trace_recursion.
293  * As we need a way to maintain state if we are tracing the function
294  * graph in irq because we want to trace a particular function that
295  * was called in irq context but we have irq tracing off. Since this
296  * can only be modified by current, we can reuse trace_recursion.
297  */
298 #define TRACE_IRQ_BIT			(1<<13)
299 
300 #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (bit); } while (0)
301 #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(bit); } while (0)
302 #define trace_recursion_test(bit)	((current)->trace_recursion & (bit))
303 
304 #define TRACE_PIPE_ALL_CPU	-1
305 
306 int tracer_init(struct tracer *t, struct trace_array *tr);
307 int tracing_is_enabled(void);
308 void trace_wake_up(void);
309 void tracing_reset(struct trace_array *tr, int cpu);
310 void tracing_reset_online_cpus(struct trace_array *tr);
311 void tracing_reset_current(int cpu);
312 void tracing_reset_current_online_cpus(void);
313 int tracing_open_generic(struct inode *inode, struct file *filp);
314 struct dentry *trace_create_file(const char *name,
315 				 mode_t mode,
316 				 struct dentry *parent,
317 				 void *data,
318 				 const struct file_operations *fops);
319 
320 struct dentry *tracing_init_dentry(void);
321 
322 struct ring_buffer_event;
323 
324 struct ring_buffer_event *
325 trace_buffer_lock_reserve(struct ring_buffer *buffer,
326 			  int type,
327 			  unsigned long len,
328 			  unsigned long flags,
329 			  int pc);
330 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
331 				struct ring_buffer_event *event,
332 				unsigned long flags, int pc);
333 
334 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
335 						struct trace_array_cpu *data);
336 
337 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
338 					  int *ent_cpu, u64 *ent_ts);
339 
340 int trace_empty(struct trace_iterator *iter);
341 
342 void *trace_find_next_entry_inc(struct trace_iterator *iter);
343 
344 void trace_init_global_iter(struct trace_iterator *iter);
345 
346 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
347 
348 void default_wait_pipe(struct trace_iterator *iter);
349 void poll_wait_pipe(struct trace_iterator *iter);
350 
351 void ftrace(struct trace_array *tr,
352 			    struct trace_array_cpu *data,
353 			    unsigned long ip,
354 			    unsigned long parent_ip,
355 			    unsigned long flags, int pc);
356 void tracing_sched_switch_trace(struct trace_array *tr,
357 				struct task_struct *prev,
358 				struct task_struct *next,
359 				unsigned long flags, int pc);
360 
361 void tracing_sched_wakeup_trace(struct trace_array *tr,
362 				struct task_struct *wakee,
363 				struct task_struct *cur,
364 				unsigned long flags, int pc);
365 void trace_function(struct trace_array *tr,
366 		    unsigned long ip,
367 		    unsigned long parent_ip,
368 		    unsigned long flags, int pc);
369 void trace_graph_function(struct trace_array *tr,
370 		    unsigned long ip,
371 		    unsigned long parent_ip,
372 		    unsigned long flags, int pc);
373 void trace_default_header(struct seq_file *m);
374 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
375 int trace_empty(struct trace_iterator *iter);
376 
377 void trace_graph_return(struct ftrace_graph_ret *trace);
378 int trace_graph_entry(struct ftrace_graph_ent *trace);
379 void set_graph_array(struct trace_array *tr);
380 
381 void tracing_start_cmdline_record(void);
382 void tracing_stop_cmdline_record(void);
383 void tracing_sched_switch_assign_trace(struct trace_array *tr);
384 void tracing_stop_sched_switch_record(void);
385 void tracing_start_sched_switch_record(void);
386 int register_tracer(struct tracer *type);
387 void unregister_tracer(struct tracer *type);
388 int is_tracing_stopped(void);
389 enum trace_file_type {
390 	TRACE_FILE_LAT_FMT	= 1,
391 	TRACE_FILE_ANNOTATE	= 2,
392 };
393 
394 extern cpumask_var_t __read_mostly tracing_buffer_mask;
395 
396 #define for_each_tracing_cpu(cpu)	\
397 	for_each_cpu(cpu, tracing_buffer_mask)
398 
399 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
400 
401 extern unsigned long tracing_thresh;
402 
403 #ifdef CONFIG_TRACER_MAX_TRACE
404 extern unsigned long tracing_max_latency;
405 
406 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
407 void update_max_tr_single(struct trace_array *tr,
408 			  struct task_struct *tsk, int cpu);
409 #endif /* CONFIG_TRACER_MAX_TRACE */
410 
411 #ifdef CONFIG_STACKTRACE
412 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
413 			int skip, int pc);
414 
415 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
416 			     int skip, int pc, struct pt_regs *regs);
417 
418 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
419 			    int pc);
420 
421 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
422 		   int pc);
423 #else
424 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
425 				      unsigned long flags, int skip, int pc)
426 {
427 }
428 
429 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
430 					   unsigned long flags, int skip,
431 					   int pc, struct pt_regs *regs)
432 {
433 }
434 
435 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
436 					  unsigned long flags, int pc)
437 {
438 }
439 
440 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
441 				 int skip, int pc)
442 {
443 }
444 #endif /* CONFIG_STACKTRACE */
445 
446 extern cycle_t ftrace_now(int cpu);
447 
448 extern void trace_find_cmdline(int pid, char comm[]);
449 
450 #ifdef CONFIG_DYNAMIC_FTRACE
451 extern unsigned long ftrace_update_tot_cnt;
452 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
453 extern int DYN_FTRACE_TEST_NAME(void);
454 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
455 extern int DYN_FTRACE_TEST_NAME2(void);
456 #endif
457 
458 extern int ring_buffer_expanded;
459 extern bool tracing_selftest_disabled;
460 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
461 
462 #ifdef CONFIG_FTRACE_STARTUP_TEST
463 extern int trace_selftest_startup_function(struct tracer *trace,
464 					   struct trace_array *tr);
465 extern int trace_selftest_startup_function_graph(struct tracer *trace,
466 						 struct trace_array *tr);
467 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
468 					  struct trace_array *tr);
469 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
470 					     struct trace_array *tr);
471 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
472 						 struct trace_array *tr);
473 extern int trace_selftest_startup_wakeup(struct tracer *trace,
474 					 struct trace_array *tr);
475 extern int trace_selftest_startup_nop(struct tracer *trace,
476 					 struct trace_array *tr);
477 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
478 					       struct trace_array *tr);
479 extern int trace_selftest_startup_branch(struct tracer *trace,
480 					 struct trace_array *tr);
481 #endif /* CONFIG_FTRACE_STARTUP_TEST */
482 
483 extern void *head_page(struct trace_array_cpu *data);
484 extern unsigned long long ns2usecs(cycle_t nsec);
485 extern int
486 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
487 extern int
488 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
489 extern int
490 trace_array_vprintk(struct trace_array *tr,
491 		    unsigned long ip, const char *fmt, va_list args);
492 int trace_array_printk(struct trace_array *tr,
493 		       unsigned long ip, const char *fmt, ...);
494 void trace_printk_seq(struct trace_seq *s);
495 enum print_line_t print_trace_line(struct trace_iterator *iter);
496 
497 extern unsigned long trace_flags;
498 
499 extern int trace_clock_id;
500 
501 /* Standard output formatting function used for function return traces */
502 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
503 
504 /* Flag options */
505 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
506 #define TRACE_GRAPH_PRINT_CPU           0x2
507 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
508 #define TRACE_GRAPH_PRINT_PROC          0x8
509 #define TRACE_GRAPH_PRINT_DURATION      0x10
510 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
511 
512 extern enum print_line_t
513 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
514 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
515 extern enum print_line_t
516 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
517 extern void graph_trace_open(struct trace_iterator *iter);
518 extern void graph_trace_close(struct trace_iterator *iter);
519 extern int __trace_graph_entry(struct trace_array *tr,
520 			       struct ftrace_graph_ent *trace,
521 			       unsigned long flags, int pc);
522 extern void __trace_graph_return(struct trace_array *tr,
523 				 struct ftrace_graph_ret *trace,
524 				 unsigned long flags, int pc);
525 
526 
527 #ifdef CONFIG_DYNAMIC_FTRACE
528 /* TODO: make this variable */
529 #define FTRACE_GRAPH_MAX_FUNCS		32
530 extern int ftrace_graph_filter_enabled;
531 extern int ftrace_graph_count;
532 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
533 
534 static inline int ftrace_graph_addr(unsigned long addr)
535 {
536 	int i;
537 
538 	if (!ftrace_graph_filter_enabled)
539 		return 1;
540 
541 	for (i = 0; i < ftrace_graph_count; i++) {
542 		if (addr == ftrace_graph_funcs[i]) {
543 			/*
544 			 * If no irqs are to be traced, but a set_graph_function
545 			 * is set, and called by an interrupt handler, we still
546 			 * want to trace it.
547 			 */
548 			if (in_irq())
549 				trace_recursion_set(TRACE_IRQ_BIT);
550 			else
551 				trace_recursion_clear(TRACE_IRQ_BIT);
552 			return 1;
553 		}
554 	}
555 
556 	return 0;
557 }
558 #else
559 static inline int ftrace_graph_addr(unsigned long addr)
560 {
561 	return 1;
562 }
563 #endif /* CONFIG_DYNAMIC_FTRACE */
564 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
565 static inline enum print_line_t
566 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
567 {
568 	return TRACE_TYPE_UNHANDLED;
569 }
570 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
571 
572 extern struct list_head ftrace_pids;
573 
574 #ifdef CONFIG_FUNCTION_TRACER
575 static inline int ftrace_trace_task(struct task_struct *task)
576 {
577 	if (list_empty(&ftrace_pids))
578 		return 1;
579 
580 	return test_tsk_trace_trace(task);
581 }
582 #else
583 static inline int ftrace_trace_task(struct task_struct *task)
584 {
585 	return 1;
586 }
587 #endif
588 
589 /*
590  * struct trace_parser - servers for reading the user input separated by spaces
591  * @cont: set if the input is not complete - no final space char was found
592  * @buffer: holds the parsed user input
593  * @idx: user input length
594  * @size: buffer size
595  */
596 struct trace_parser {
597 	bool		cont;
598 	char		*buffer;
599 	unsigned	idx;
600 	unsigned	size;
601 };
602 
603 static inline bool trace_parser_loaded(struct trace_parser *parser)
604 {
605 	return (parser->idx != 0);
606 }
607 
608 static inline bool trace_parser_cont(struct trace_parser *parser)
609 {
610 	return parser->cont;
611 }
612 
613 static inline void trace_parser_clear(struct trace_parser *parser)
614 {
615 	parser->cont = false;
616 	parser->idx = 0;
617 }
618 
619 extern int trace_parser_get_init(struct trace_parser *parser, int size);
620 extern void trace_parser_put(struct trace_parser *parser);
621 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
622 	size_t cnt, loff_t *ppos);
623 
624 /*
625  * trace_iterator_flags is an enumeration that defines bit
626  * positions into trace_flags that controls the output.
627  *
628  * NOTE: These bits must match the trace_options array in
629  *       trace.c.
630  */
631 enum trace_iterator_flags {
632 	TRACE_ITER_PRINT_PARENT		= 0x01,
633 	TRACE_ITER_SYM_OFFSET		= 0x02,
634 	TRACE_ITER_SYM_ADDR		= 0x04,
635 	TRACE_ITER_VERBOSE		= 0x08,
636 	TRACE_ITER_RAW			= 0x10,
637 	TRACE_ITER_HEX			= 0x20,
638 	TRACE_ITER_BIN			= 0x40,
639 	TRACE_ITER_BLOCK		= 0x80,
640 	TRACE_ITER_STACKTRACE		= 0x100,
641 	TRACE_ITER_PRINTK		= 0x200,
642 	TRACE_ITER_PREEMPTONLY		= 0x400,
643 	TRACE_ITER_BRANCH		= 0x800,
644 	TRACE_ITER_ANNOTATE		= 0x1000,
645 	TRACE_ITER_USERSTACKTRACE       = 0x2000,
646 	TRACE_ITER_SYM_USEROBJ          = 0x4000,
647 	TRACE_ITER_PRINTK_MSGONLY	= 0x8000,
648 	TRACE_ITER_CONTEXT_INFO		= 0x10000, /* Print pid/cpu/time */
649 	TRACE_ITER_LATENCY_FMT		= 0x20000,
650 	TRACE_ITER_SLEEP_TIME		= 0x40000,
651 	TRACE_ITER_GRAPH_TIME		= 0x80000,
652 	TRACE_ITER_RECORD_CMD		= 0x100000,
653 	TRACE_ITER_OVERWRITE		= 0x200000,
654 	TRACE_ITER_STOP_ON_FREE		= 0x400000,
655 };
656 
657 /*
658  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
659  * control the output of kernel symbols.
660  */
661 #define TRACE_ITER_SYM_MASK \
662 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
663 
664 extern struct tracer nop_trace;
665 
666 #ifdef CONFIG_BRANCH_TRACER
667 extern int enable_branch_tracing(struct trace_array *tr);
668 extern void disable_branch_tracing(void);
669 static inline int trace_branch_enable(struct trace_array *tr)
670 {
671 	if (trace_flags & TRACE_ITER_BRANCH)
672 		return enable_branch_tracing(tr);
673 	return 0;
674 }
675 static inline void trace_branch_disable(void)
676 {
677 	/* due to races, always disable */
678 	disable_branch_tracing();
679 }
680 #else
681 static inline int trace_branch_enable(struct trace_array *tr)
682 {
683 	return 0;
684 }
685 static inline void trace_branch_disable(void)
686 {
687 }
688 #endif /* CONFIG_BRANCH_TRACER */
689 
690 /* set ring buffers to default size if not already done so */
691 int tracing_update_buffers(void);
692 
693 /* trace event type bit fields, not numeric */
694 enum {
695 	TRACE_EVENT_TYPE_PRINTF		= 1,
696 	TRACE_EVENT_TYPE_RAW		= 2,
697 };
698 
699 struct ftrace_event_field {
700 	struct list_head	link;
701 	char			*name;
702 	char			*type;
703 	int			filter_type;
704 	int			offset;
705 	int			size;
706 	int			is_signed;
707 };
708 
709 struct event_filter {
710 	int			n_preds;	/* Number assigned */
711 	int			a_preds;	/* allocated */
712 	struct filter_pred	*preds;
713 	struct filter_pred	*root;
714 	char			*filter_string;
715 };
716 
717 struct event_subsystem {
718 	struct list_head	list;
719 	const char		*name;
720 	struct dentry		*entry;
721 	struct event_filter	*filter;
722 	int			nr_events;
723 	int			ref_count;
724 };
725 
726 #define FILTER_PRED_INVALID	((unsigned short)-1)
727 #define FILTER_PRED_IS_RIGHT	(1 << 15)
728 #define FILTER_PRED_FOLD	(1 << 15)
729 
730 /*
731  * The max preds is the size of unsigned short with
732  * two flags at the MSBs. One bit is used for both the IS_RIGHT
733  * and FOLD flags. The other is reserved.
734  *
735  * 2^14 preds is way more than enough.
736  */
737 #define MAX_FILTER_PRED		16384
738 
739 struct filter_pred;
740 struct regex;
741 
742 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
743 
744 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
745 
746 enum regex_type {
747 	MATCH_FULL = 0,
748 	MATCH_FRONT_ONLY,
749 	MATCH_MIDDLE_ONLY,
750 	MATCH_END_ONLY,
751 };
752 
753 struct regex {
754 	char			pattern[MAX_FILTER_STR_VAL];
755 	int			len;
756 	int			field_len;
757 	regex_match_func	match;
758 };
759 
760 struct filter_pred {
761 	filter_pred_fn_t 	fn;
762 	u64 			val;
763 	struct regex		regex;
764 	/*
765 	 * Leaf nodes use field_name, ops is used by AND and OR
766 	 * nodes. The field_name is always freed when freeing a pred.
767 	 * We can overload field_name for ops and have it freed
768 	 * as well.
769 	 */
770 	union {
771 		char		*field_name;
772 		unsigned short	*ops;
773 	};
774 	int 			offset;
775 	int 			not;
776 	int 			op;
777 	unsigned short		index;
778 	unsigned short		parent;
779 	unsigned short		left;
780 	unsigned short		right;
781 };
782 
783 extern struct list_head ftrace_common_fields;
784 
785 extern enum regex_type
786 filter_parse_regex(char *buff, int len, char **search, int *not);
787 extern void print_event_filter(struct ftrace_event_call *call,
788 			       struct trace_seq *s);
789 extern int apply_event_filter(struct ftrace_event_call *call,
790 			      char *filter_string);
791 extern int apply_subsystem_event_filter(struct event_subsystem *system,
792 					char *filter_string);
793 extern void print_subsystem_event_filter(struct event_subsystem *system,
794 					 struct trace_seq *s);
795 extern int filter_assign_type(const char *type);
796 
797 struct list_head *
798 trace_get_fields(struct ftrace_event_call *event_call);
799 
800 static inline int
801 filter_check_discard(struct ftrace_event_call *call, void *rec,
802 		     struct ring_buffer *buffer,
803 		     struct ring_buffer_event *event)
804 {
805 	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
806 	    !filter_match_preds(call->filter, rec)) {
807 		ring_buffer_discard_commit(buffer, event);
808 		return 1;
809 	}
810 
811 	return 0;
812 }
813 
814 extern void trace_event_enable_cmd_record(bool enable);
815 
816 extern struct mutex event_mutex;
817 extern struct list_head ftrace_events;
818 
819 extern const char *__start___trace_bprintk_fmt[];
820 extern const char *__stop___trace_bprintk_fmt[];
821 
822 #undef FTRACE_ENTRY
823 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)		\
824 	extern struct ftrace_event_call					\
825 	__attribute__((__aligned__(4))) event_##call;
826 #undef FTRACE_ENTRY_DUP
827 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)		\
828 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
829 #include "trace_entries.h"
830 
831 #endif /* _LINUX_KERNEL_TRACE_H */
832