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 	/* Return 0 if OK with change, else return non-zero */
282 	int			(*flag_changed)(struct tracer *tracer,
283 						u32 mask, int set);
284 	struct tracer		*next;
285 	struct tracer_flags	*flags;
286 	int			print_max;
287 	int			use_max_tr;
288 	bool			enabled;
289 };
290 
291 
292 /* Only current can touch trace_recursion */
293 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
294 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
295 
296 /* Ring buffer has the 10 LSB bits to count */
297 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
298 
299 /* for function tracing recursion */
300 #define TRACE_INTERNAL_BIT		(1<<11)
301 #define TRACE_GLOBAL_BIT		(1<<12)
302 #define TRACE_CONTROL_BIT		(1<<13)
303 
304 /*
305  * Abuse of the trace_recursion.
306  * As we need a way to maintain state if we are tracing the function
307  * graph in irq because we want to trace a particular function that
308  * was called in irq context but we have irq tracing off. Since this
309  * can only be modified by current, we can reuse trace_recursion.
310  */
311 #define TRACE_IRQ_BIT			(1<<13)
312 
313 #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (bit); } while (0)
314 #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(bit); } while (0)
315 #define trace_recursion_test(bit)	((current)->trace_recursion & (bit))
316 
317 #define TRACE_PIPE_ALL_CPU	-1
318 
319 int tracer_init(struct tracer *t, struct trace_array *tr);
320 int tracing_is_enabled(void);
321 void trace_wake_up(void);
322 void tracing_reset(struct trace_array *tr, int cpu);
323 void tracing_reset_online_cpus(struct trace_array *tr);
324 void tracing_reset_current(int cpu);
325 void tracing_reset_current_online_cpus(void);
326 int tracing_open_generic(struct inode *inode, struct file *filp);
327 struct dentry *trace_create_file(const char *name,
328 				 umode_t mode,
329 				 struct dentry *parent,
330 				 void *data,
331 				 const struct file_operations *fops);
332 
333 struct dentry *tracing_init_dentry(void);
334 
335 struct ring_buffer_event;
336 
337 struct ring_buffer_event *
338 trace_buffer_lock_reserve(struct ring_buffer *buffer,
339 			  int type,
340 			  unsigned long len,
341 			  unsigned long flags,
342 			  int pc);
343 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
344 				struct ring_buffer_event *event,
345 				unsigned long flags, int pc);
346 
347 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
348 						struct trace_array_cpu *data);
349 
350 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
351 					  int *ent_cpu, u64 *ent_ts);
352 
353 int trace_empty(struct trace_iterator *iter);
354 
355 void *trace_find_next_entry_inc(struct trace_iterator *iter);
356 
357 void trace_init_global_iter(struct trace_iterator *iter);
358 
359 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
360 
361 void default_wait_pipe(struct trace_iterator *iter);
362 void poll_wait_pipe(struct trace_iterator *iter);
363 
364 void ftrace(struct trace_array *tr,
365 			    struct trace_array_cpu *data,
366 			    unsigned long ip,
367 			    unsigned long parent_ip,
368 			    unsigned long flags, int pc);
369 void tracing_sched_switch_trace(struct trace_array *tr,
370 				struct task_struct *prev,
371 				struct task_struct *next,
372 				unsigned long flags, int pc);
373 
374 void tracing_sched_wakeup_trace(struct trace_array *tr,
375 				struct task_struct *wakee,
376 				struct task_struct *cur,
377 				unsigned long flags, int pc);
378 void trace_function(struct trace_array *tr,
379 		    unsigned long ip,
380 		    unsigned long parent_ip,
381 		    unsigned long flags, int pc);
382 void trace_graph_function(struct trace_array *tr,
383 		    unsigned long ip,
384 		    unsigned long parent_ip,
385 		    unsigned long flags, int pc);
386 void trace_latency_header(struct seq_file *m);
387 void trace_default_header(struct seq_file *m);
388 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
389 int trace_empty(struct trace_iterator *iter);
390 
391 void trace_graph_return(struct ftrace_graph_ret *trace);
392 int trace_graph_entry(struct ftrace_graph_ent *trace);
393 void set_graph_array(struct trace_array *tr);
394 
395 void tracing_start_cmdline_record(void);
396 void tracing_stop_cmdline_record(void);
397 void tracing_sched_switch_assign_trace(struct trace_array *tr);
398 void tracing_stop_sched_switch_record(void);
399 void tracing_start_sched_switch_record(void);
400 int register_tracer(struct tracer *type);
401 void unregister_tracer(struct tracer *type);
402 int is_tracing_stopped(void);
403 enum trace_file_type {
404 	TRACE_FILE_LAT_FMT	= 1,
405 	TRACE_FILE_ANNOTATE	= 2,
406 };
407 
408 extern cpumask_var_t __read_mostly tracing_buffer_mask;
409 
410 #define for_each_tracing_cpu(cpu)	\
411 	for_each_cpu(cpu, tracing_buffer_mask)
412 
413 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
414 
415 extern unsigned long tracing_thresh;
416 
417 #ifdef CONFIG_TRACER_MAX_TRACE
418 extern unsigned long tracing_max_latency;
419 
420 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
421 void update_max_tr_single(struct trace_array *tr,
422 			  struct task_struct *tsk, int cpu);
423 #endif /* CONFIG_TRACER_MAX_TRACE */
424 
425 #ifdef CONFIG_STACKTRACE
426 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
427 			int skip, int pc);
428 
429 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
430 			     int skip, int pc, struct pt_regs *regs);
431 
432 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
433 			    int pc);
434 
435 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
436 		   int pc);
437 #else
ftrace_trace_stack(struct ring_buffer * buffer,unsigned long flags,int skip,int pc)438 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
439 				      unsigned long flags, int skip, int pc)
440 {
441 }
442 
ftrace_trace_stack_regs(struct ring_buffer * buffer,unsigned long flags,int skip,int pc,struct pt_regs * regs)443 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
444 					   unsigned long flags, int skip,
445 					   int pc, struct pt_regs *regs)
446 {
447 }
448 
ftrace_trace_userstack(struct ring_buffer * buffer,unsigned long flags,int pc)449 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
450 					  unsigned long flags, int pc)
451 {
452 }
453 
__trace_stack(struct trace_array * tr,unsigned long flags,int skip,int pc)454 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
455 				 int skip, int pc)
456 {
457 }
458 #endif /* CONFIG_STACKTRACE */
459 
460 extern cycle_t ftrace_now(int cpu);
461 
462 extern void trace_find_cmdline(int pid, char comm[]);
463 
464 #ifdef CONFIG_DYNAMIC_FTRACE
465 extern unsigned long ftrace_update_tot_cnt;
466 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
467 extern int DYN_FTRACE_TEST_NAME(void);
468 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
469 extern int DYN_FTRACE_TEST_NAME2(void);
470 #endif
471 
472 extern int ring_buffer_expanded;
473 extern bool tracing_selftest_disabled;
474 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
475 
476 #ifdef CONFIG_FTRACE_STARTUP_TEST
477 extern int trace_selftest_startup_function(struct tracer *trace,
478 					   struct trace_array *tr);
479 extern int trace_selftest_startup_function_graph(struct tracer *trace,
480 						 struct trace_array *tr);
481 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
482 					  struct trace_array *tr);
483 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
484 					     struct trace_array *tr);
485 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
486 						 struct trace_array *tr);
487 extern int trace_selftest_startup_wakeup(struct tracer *trace,
488 					 struct trace_array *tr);
489 extern int trace_selftest_startup_nop(struct tracer *trace,
490 					 struct trace_array *tr);
491 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
492 					       struct trace_array *tr);
493 extern int trace_selftest_startup_branch(struct tracer *trace,
494 					 struct trace_array *tr);
495 #endif /* CONFIG_FTRACE_STARTUP_TEST */
496 
497 extern void *head_page(struct trace_array_cpu *data);
498 extern unsigned long long ns2usecs(cycle_t nsec);
499 extern int
500 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
501 extern int
502 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
503 extern int
504 trace_array_vprintk(struct trace_array *tr,
505 		    unsigned long ip, const char *fmt, va_list args);
506 int trace_array_printk(struct trace_array *tr,
507 		       unsigned long ip, const char *fmt, ...);
508 void trace_printk_seq(struct trace_seq *s);
509 enum print_line_t print_trace_line(struct trace_iterator *iter);
510 
511 extern unsigned long trace_flags;
512 
513 extern int trace_clock_id;
514 
515 /* Standard output formatting function used for function return traces */
516 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
517 
518 /* Flag options */
519 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
520 #define TRACE_GRAPH_PRINT_CPU           0x2
521 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
522 #define TRACE_GRAPH_PRINT_PROC          0x8
523 #define TRACE_GRAPH_PRINT_DURATION      0x10
524 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
525 
526 extern enum print_line_t
527 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
528 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
529 extern enum print_line_t
530 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
531 extern void graph_trace_open(struct trace_iterator *iter);
532 extern void graph_trace_close(struct trace_iterator *iter);
533 extern int __trace_graph_entry(struct trace_array *tr,
534 			       struct ftrace_graph_ent *trace,
535 			       unsigned long flags, int pc);
536 extern void __trace_graph_return(struct trace_array *tr,
537 				 struct ftrace_graph_ret *trace,
538 				 unsigned long flags, int pc);
539 
540 
541 #ifdef CONFIG_DYNAMIC_FTRACE
542 /* TODO: make this variable */
543 #define FTRACE_GRAPH_MAX_FUNCS		32
544 extern int ftrace_graph_filter_enabled;
545 extern int ftrace_graph_count;
546 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
547 
ftrace_graph_addr(unsigned long addr)548 static inline int ftrace_graph_addr(unsigned long addr)
549 {
550 	int i;
551 
552 	if (!ftrace_graph_filter_enabled)
553 		return 1;
554 
555 	for (i = 0; i < ftrace_graph_count; i++) {
556 		if (addr == ftrace_graph_funcs[i]) {
557 			/*
558 			 * If no irqs are to be traced, but a set_graph_function
559 			 * is set, and called by an interrupt handler, we still
560 			 * want to trace it.
561 			 */
562 			if (in_irq())
563 				trace_recursion_set(TRACE_IRQ_BIT);
564 			else
565 				trace_recursion_clear(TRACE_IRQ_BIT);
566 			return 1;
567 		}
568 	}
569 
570 	return 0;
571 }
572 #else
ftrace_graph_addr(unsigned long addr)573 static inline int ftrace_graph_addr(unsigned long addr)
574 {
575 	return 1;
576 }
577 #endif /* CONFIG_DYNAMIC_FTRACE */
578 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
579 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)580 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
581 {
582 	return TRACE_TYPE_UNHANDLED;
583 }
584 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
585 
586 extern struct list_head ftrace_pids;
587 
588 #ifdef CONFIG_FUNCTION_TRACER
ftrace_trace_task(struct task_struct * task)589 static inline int ftrace_trace_task(struct task_struct *task)
590 {
591 	if (list_empty(&ftrace_pids))
592 		return 1;
593 
594 	return test_tsk_trace_trace(task);
595 }
596 extern int ftrace_is_dead(void);
597 #else
ftrace_trace_task(struct task_struct * task)598 static inline int ftrace_trace_task(struct task_struct *task)
599 {
600 	return 1;
601 }
ftrace_is_dead(void)602 static inline int ftrace_is_dead(void) { return 0; }
603 #endif
604 
605 int ftrace_event_is_function(struct ftrace_event_call *call);
606 
607 /*
608  * struct trace_parser - servers for reading the user input separated by spaces
609  * @cont: set if the input is not complete - no final space char was found
610  * @buffer: holds the parsed user input
611  * @idx: user input length
612  * @size: buffer size
613  */
614 struct trace_parser {
615 	bool		cont;
616 	char		*buffer;
617 	unsigned	idx;
618 	unsigned	size;
619 };
620 
trace_parser_loaded(struct trace_parser * parser)621 static inline bool trace_parser_loaded(struct trace_parser *parser)
622 {
623 	return (parser->idx != 0);
624 }
625 
trace_parser_cont(struct trace_parser * parser)626 static inline bool trace_parser_cont(struct trace_parser *parser)
627 {
628 	return parser->cont;
629 }
630 
trace_parser_clear(struct trace_parser * parser)631 static inline void trace_parser_clear(struct trace_parser *parser)
632 {
633 	parser->cont = false;
634 	parser->idx = 0;
635 }
636 
637 extern int trace_parser_get_init(struct trace_parser *parser, int size);
638 extern void trace_parser_put(struct trace_parser *parser);
639 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
640 	size_t cnt, loff_t *ppos);
641 
642 /*
643  * trace_iterator_flags is an enumeration that defines bit
644  * positions into trace_flags that controls the output.
645  *
646  * NOTE: These bits must match the trace_options array in
647  *       trace.c.
648  */
649 enum trace_iterator_flags {
650 	TRACE_ITER_PRINT_PARENT		= 0x01,
651 	TRACE_ITER_SYM_OFFSET		= 0x02,
652 	TRACE_ITER_SYM_ADDR		= 0x04,
653 	TRACE_ITER_VERBOSE		= 0x08,
654 	TRACE_ITER_RAW			= 0x10,
655 	TRACE_ITER_HEX			= 0x20,
656 	TRACE_ITER_BIN			= 0x40,
657 	TRACE_ITER_BLOCK		= 0x80,
658 	TRACE_ITER_STACKTRACE		= 0x100,
659 	TRACE_ITER_PRINTK		= 0x200,
660 	TRACE_ITER_PREEMPTONLY		= 0x400,
661 	TRACE_ITER_BRANCH		= 0x800,
662 	TRACE_ITER_ANNOTATE		= 0x1000,
663 	TRACE_ITER_USERSTACKTRACE       = 0x2000,
664 	TRACE_ITER_SYM_USEROBJ          = 0x4000,
665 	TRACE_ITER_PRINTK_MSGONLY	= 0x8000,
666 	TRACE_ITER_CONTEXT_INFO		= 0x10000, /* Print pid/cpu/time */
667 	TRACE_ITER_LATENCY_FMT		= 0x20000,
668 	TRACE_ITER_SLEEP_TIME		= 0x40000,
669 	TRACE_ITER_GRAPH_TIME		= 0x80000,
670 	TRACE_ITER_RECORD_CMD		= 0x100000,
671 	TRACE_ITER_OVERWRITE		= 0x200000,
672 	TRACE_ITER_STOP_ON_FREE		= 0x400000,
673 	TRACE_ITER_IRQ_INFO		= 0x800000,
674 };
675 
676 /*
677  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
678  * control the output of kernel symbols.
679  */
680 #define TRACE_ITER_SYM_MASK \
681 	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
682 
683 extern struct tracer nop_trace;
684 
685 #ifdef CONFIG_BRANCH_TRACER
686 extern int enable_branch_tracing(struct trace_array *tr);
687 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)688 static inline int trace_branch_enable(struct trace_array *tr)
689 {
690 	if (trace_flags & TRACE_ITER_BRANCH)
691 		return enable_branch_tracing(tr);
692 	return 0;
693 }
trace_branch_disable(void)694 static inline void trace_branch_disable(void)
695 {
696 	/* due to races, always disable */
697 	disable_branch_tracing();
698 }
699 #else
trace_branch_enable(struct trace_array * tr)700 static inline int trace_branch_enable(struct trace_array *tr)
701 {
702 	return 0;
703 }
trace_branch_disable(void)704 static inline void trace_branch_disable(void)
705 {
706 }
707 #endif /* CONFIG_BRANCH_TRACER */
708 
709 /* set ring buffers to default size if not already done so */
710 int tracing_update_buffers(void);
711 
712 /* trace event type bit fields, not numeric */
713 enum {
714 	TRACE_EVENT_TYPE_PRINTF		= 1,
715 	TRACE_EVENT_TYPE_RAW		= 2,
716 };
717 
718 struct ftrace_event_field {
719 	struct list_head	link;
720 	char			*name;
721 	char			*type;
722 	int			filter_type;
723 	int			offset;
724 	int			size;
725 	int			is_signed;
726 };
727 
728 struct event_filter {
729 	int			n_preds;	/* Number assigned */
730 	int			a_preds;	/* allocated */
731 	struct filter_pred	*preds;
732 	struct filter_pred	*root;
733 	char			*filter_string;
734 };
735 
736 struct event_subsystem {
737 	struct list_head	list;
738 	const char		*name;
739 	struct dentry		*entry;
740 	struct event_filter	*filter;
741 	int			nr_events;
742 	int			ref_count;
743 };
744 
745 #define FILTER_PRED_INVALID	((unsigned short)-1)
746 #define FILTER_PRED_IS_RIGHT	(1 << 15)
747 #define FILTER_PRED_FOLD	(1 << 15)
748 
749 /*
750  * The max preds is the size of unsigned short with
751  * two flags at the MSBs. One bit is used for both the IS_RIGHT
752  * and FOLD flags. The other is reserved.
753  *
754  * 2^14 preds is way more than enough.
755  */
756 #define MAX_FILTER_PRED		16384
757 
758 struct filter_pred;
759 struct regex;
760 
761 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
762 
763 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
764 
765 enum regex_type {
766 	MATCH_FULL = 0,
767 	MATCH_FRONT_ONLY,
768 	MATCH_MIDDLE_ONLY,
769 	MATCH_END_ONLY,
770 };
771 
772 struct regex {
773 	char			pattern[MAX_FILTER_STR_VAL];
774 	int			len;
775 	int			field_len;
776 	regex_match_func	match;
777 };
778 
779 struct filter_pred {
780 	filter_pred_fn_t 	fn;
781 	u64 			val;
782 	struct regex		regex;
783 	unsigned short		*ops;
784 	struct ftrace_event_field *field;
785 	int 			offset;
786 	int 			not;
787 	int 			op;
788 	unsigned short		index;
789 	unsigned short		parent;
790 	unsigned short		left;
791 	unsigned short		right;
792 };
793 
794 extern struct list_head ftrace_common_fields;
795 
796 extern enum regex_type
797 filter_parse_regex(char *buff, int len, char **search, int *not);
798 extern void print_event_filter(struct ftrace_event_call *call,
799 			       struct trace_seq *s);
800 extern int apply_event_filter(struct ftrace_event_call *call,
801 			      char *filter_string);
802 extern int apply_subsystem_event_filter(struct event_subsystem *system,
803 					char *filter_string);
804 extern void print_subsystem_event_filter(struct event_subsystem *system,
805 					 struct trace_seq *s);
806 extern int filter_assign_type(const char *type);
807 
808 struct list_head *
809 trace_get_fields(struct ftrace_event_call *event_call);
810 
811 static inline int
filter_check_discard(struct ftrace_event_call * call,void * rec,struct ring_buffer * buffer,struct ring_buffer_event * event)812 filter_check_discard(struct ftrace_event_call *call, void *rec,
813 		     struct ring_buffer *buffer,
814 		     struct ring_buffer_event *event)
815 {
816 	if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
817 	    !filter_match_preds(call->filter, rec)) {
818 		ring_buffer_discard_commit(buffer, event);
819 		return 1;
820 	}
821 
822 	return 0;
823 }
824 
825 extern void trace_event_enable_cmd_record(bool enable);
826 
827 extern struct mutex event_mutex;
828 extern struct list_head ftrace_events;
829 
830 extern const char *__start___trace_bprintk_fmt[];
831 extern const char *__stop___trace_bprintk_fmt[];
832 
833 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
834 int set_tracer_flag(unsigned int mask, int enabled);
835 
836 #undef FTRACE_ENTRY
837 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
838 	extern struct ftrace_event_call					\
839 	__attribute__((__aligned__(4))) event_##call;
840 #undef FTRACE_ENTRY_DUP
841 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
842 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
843 		     filter)
844 #include "trace_entries.h"
845 
846 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
847 int perf_ftrace_event_register(struct ftrace_event_call *call,
848 			       enum trace_reg type, void *data);
849 #else
850 #define perf_ftrace_event_register NULL
851 #endif
852 
853 #endif /* _LINUX_KERNEL_TRACE_H */
854