trace.h 20.9 KB
Newer Older
1 2 3 4 5 6 7
#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H

#include <linux/fs.h>
#include <asm/atomic.h>
#include <linux/sched.h>
#include <linux/clocksource.h>
8
#include <linux/ring_buffer.h>
P
Pekka Paalanen 已提交
9
#include <linux/mmiotrace.h>
10
#include <linux/ftrace.h>
11
#include <trace/boot.h>
12
#include <trace/kmemtrace.h>
13
#include <trace/power.h>
14

15 16 17 18 19 20 21
enum trace_type {
	__TRACE_FIRST_TYPE = 0,

	TRACE_FN,
	TRACE_CTX,
	TRACE_WAKE,
	TRACE_STACK,
22
	TRACE_PRINT,
23
	TRACE_BPRINT,
24
	TRACE_SPECIAL,
P
Pekka Paalanen 已提交
25 26
	TRACE_MMIO_RW,
	TRACE_MMIO_MAP,
27
	TRACE_BRANCH,
28 29
	TRACE_BOOT_CALL,
	TRACE_BOOT_RET,
30 31
	TRACE_GRAPH_RET,
	TRACE_GRAPH_ENT,
32
	TRACE_USER_STACK,
33
	TRACE_HW_BRANCHES,
34 35
	TRACE_KMEM_ALLOC,
	TRACE_KMEM_FREE,
36
	TRACE_POWER,
37
	TRACE_BLK,
38

39
	__TRACE_LAST_TYPE,
40 41
};

42 43 44 45 46 47 48 49 50 51 52
/*
 * The trace entry - the most basic unit of tracing. This is what
 * is printed in the end as a single line in the trace output, such as:
 *
 *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
 */
struct trace_entry {
	unsigned char		type;
	unsigned char		flags;
	unsigned char		preempt_count;
	int			pid;
53
	int			tgid;
54 55
};

56 57 58 59
/*
 * Function trace entry - function address and parent function addres:
 */
struct ftrace_entry {
60
	struct trace_entry	ent;
61 62 63
	unsigned long		ip;
	unsigned long		parent_ip;
};
64

65 66
/* Function call entry */
struct ftrace_graph_ent_entry {
67
	struct trace_entry		ent;
68 69 70
	struct ftrace_graph_ent		graph_ent;
};

71
/* Function return entry */
72
struct ftrace_graph_ret_entry {
73
	struct trace_entry		ent;
74
	struct ftrace_graph_ret		ret;
75
};
76
extern struct tracer boot_tracer;
77 78 79 80 81

/*
 * Context switch trace entry - which task (and prio) we switched from/to:
 */
struct ctx_switch_entry {
82
	struct trace_entry	ent;
83 84 85 86 87
	unsigned int		prev_pid;
	unsigned char		prev_prio;
	unsigned char		prev_state;
	unsigned int		next_pid;
	unsigned char		next_prio;
P
Peter Zijlstra 已提交
88
	unsigned char		next_state;
89
	unsigned int		next_cpu;
90 91
};

I
Ingo Molnar 已提交
92 93 94 95
/*
 * Special (free-form) trace entry:
 */
struct special_entry {
96
	struct trace_entry	ent;
I
Ingo Molnar 已提交
97 98 99 100 101
	unsigned long		arg1;
	unsigned long		arg2;
	unsigned long		arg3;
};

I
Ingo Molnar 已提交
102 103 104 105
/*
 * Stack-trace entry:
 */

I
Ingo Molnar 已提交
106
#define FTRACE_STACK_ENTRIES	8
I
Ingo Molnar 已提交
107 108

struct stack_entry {
109
	struct trace_entry	ent;
I
Ingo Molnar 已提交
110 111 112
	unsigned long		caller[FTRACE_STACK_ENTRIES];
};

113 114 115 116 117
struct userstack_entry {
	struct trace_entry	ent;
	unsigned long		caller[FTRACE_STACK_ENTRIES];
};

118
/*
119
 * trace_printk entry:
120
 */
121
struct bprint_entry {
122
	struct trace_entry	ent;
I
Ingo Molnar 已提交
123
	unsigned long		ip;
124
	int			depth;
125
	const char		*fmt;
I
Ingo Molnar 已提交
126
	u32			buf[];
127 128
};

129 130 131 132 133 134 135
struct print_entry {
	struct trace_entry	ent;
	unsigned long		ip;
	int			depth;
	char			buf[];
};

136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153
#define TRACE_OLD_SIZE		88

struct trace_field_cont {
	unsigned char		type;
	/* Temporary till we get rid of this completely */
	char			buf[TRACE_OLD_SIZE - 1];
};

struct trace_mmiotrace_rw {
	struct trace_entry	ent;
	struct mmiotrace_rw	rw;
};

struct trace_mmiotrace_map {
	struct trace_entry	ent;
	struct mmiotrace_map	map;
};

154
struct trace_boot_call {
155
	struct trace_entry	ent;
156 157 158 159 160 161
	struct boot_trace_call boot_call;
};

struct trace_boot_ret {
	struct trace_entry	ent;
	struct boot_trace_ret boot_ret;
162 163
};

164 165
#define TRACE_FUNC_SIZE 30
#define TRACE_FILE_SIZE 20
166
struct trace_branch {
167 168 169 170 171 172 173
	struct trace_entry	ent;
	unsigned	        line;
	char			func[TRACE_FUNC_SIZE+1];
	char			file[TRACE_FILE_SIZE+1];
	char			correct;
};

174
struct hw_branch_entry {
175
	struct trace_entry	ent;
176 177
	u64			from;
	u64			to;
178 179
};

180 181 182 183 184
struct trace_power {
	struct trace_entry	ent;
	struct power_trace	state_data;
};

185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202
struct kmemtrace_alloc_entry {
	struct trace_entry	ent;
	enum kmemtrace_type_id type_id;
	unsigned long call_site;
	const void *ptr;
	size_t bytes_req;
	size_t bytes_alloc;
	gfp_t gfp_flags;
	int node;
};

struct kmemtrace_free_entry {
	struct trace_entry	ent;
	enum kmemtrace_type_id type_id;
	unsigned long call_site;
	const void *ptr;
};

203 204 205
/*
 * trace_flag_type is an enumeration that holds different
 * states when a trace occurs. These are:
206
 *  IRQS_OFF		- interrupts were disabled
I
Ingo Molnar 已提交
207
 *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
208 209 210
 *  NEED_RESCED		- reschedule is requested
 *  HARDIRQ		- inside an interrupt handler
 *  SOFTIRQ		- inside a softirq handler
211 212 213
 */
enum trace_flag_type {
	TRACE_FLAG_IRQS_OFF		= 0x01,
214 215 216 217
	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
	TRACE_FLAG_NEED_RESCHED		= 0x04,
	TRACE_FLAG_HARDIRQ		= 0x08,
	TRACE_FLAG_SOFTIRQ		= 0x10,
218 219
};

220
#define TRACE_BUF_SIZE		1024
221 222 223 224 225 226 227 228

/*
 * The CPU trace array - it consists of thousands of trace entries
 * plus some other descriptor data: (for example which task started
 * the trace, etc.)
 */
struct trace_array_cpu {
	atomic_t		disabled;
229
	void			*buffer_page;	/* ring buffer spare */
I
Ingo Molnar 已提交
230

I
Ingo Molnar 已提交
231 232
	/* these fields get copied into max-trace: */
	unsigned long		trace_idx;
233
	unsigned long		overrun;
234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254
	unsigned long		saved_latency;
	unsigned long		critical_start;
	unsigned long		critical_end;
	unsigned long		critical_sequence;
	unsigned long		nice;
	unsigned long		policy;
	unsigned long		rt_priority;
	cycle_t			preempt_timestamp;
	pid_t			pid;
	uid_t			uid;
	char			comm[TASK_COMM_LEN];
};

struct trace_iterator;

/*
 * The trace array - an array of per-CPU trace arrays. This is the
 * highest level data structure that individual tracers deal with.
 * They have on/off state as well:
 */
struct trace_array {
255
	struct ring_buffer	*buffer;
256 257 258
	unsigned long		entries;
	int			cpu;
	cycle_t			time_start;
259
	struct task_struct	*waiter;
260 261 262
	struct trace_array_cpu	*data[NR_CPUS];
};

S
Steven Rostedt 已提交
263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294
#define FTRACE_CMP_TYPE(var, type) \
	__builtin_types_compatible_p(typeof(var), type *)

#undef IF_ASSIGN
#define IF_ASSIGN(var, entry, etype, id)		\
	if (FTRACE_CMP_TYPE(var, etype)) {		\
		var = (typeof(var))(entry);		\
		WARN_ON(id && (entry)->type != id);	\
		break;					\
	}

/* Will cause compile errors if type is not found. */
extern void __ftrace_bad_type(void);

/*
 * The trace_assign_type is a verifier that the entry type is
 * the same as the type being assigned. To add new types simply
 * add a line with the following format:
 *
 * IF_ASSIGN(var, ent, type, id);
 *
 *  Where "type" is the trace type that includes the trace_entry
 *  as the "ent" item. And "id" is the trace identifier that is
 *  used in the trace_type enum.
 *
 *  If the type can have more than one id, then use zero.
 */
#define trace_assign_type(var, ent)					\
	do {								\
		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
295
		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
S
Steven Rostedt 已提交
296
		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
297
		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
S
Steven Rostedt 已提交
298 299 300 301 302
		IF_ASSIGN(var, ent, struct special_entry, 0);		\
		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
			  TRACE_MMIO_RW);				\
		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
			  TRACE_MMIO_MAP);				\
303 304
		IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
		IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
305
		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
306 307 308 309
		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
			  TRACE_GRAPH_ENT);		\
		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
			  TRACE_GRAPH_RET);		\
310
		IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
I
Ingo Molnar 已提交
311
		IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
312 313 314 315
		IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,	\
			  TRACE_KMEM_ALLOC);	\
		IF_ASSIGN(var, ent, struct kmemtrace_free_entry,	\
			  TRACE_KMEM_FREE);	\
S
Steven Rostedt 已提交
316 317
		__ftrace_bad_type();					\
	} while (0)
318 319 320 321 322

/* Return values for print_line callback */
enum print_line_t {
	TRACE_TYPE_PARTIAL_LINE	= 0,	/* Retry after flushing the seq */
	TRACE_TYPE_HANDLED	= 1,
323 324
	TRACE_TYPE_UNHANDLED	= 2,	/* Relay to other output functions */
	TRACE_TYPE_NO_CONSUME	= 3	/* Handled but ask to not consume */
325 326
};

327 328 329 330 331 332 333

/*
 * An option specific to a tracer. This is a boolean value.
 * The bit is the bit index that sets its value on the
 * flags value in struct tracer_flags.
 */
struct tracer_opt {
I
Ingo Molnar 已提交
334 335
	const char	*name; /* Will appear on the trace_options file */
	u32		bit; /* Mask assigned in val field in tracer_flags */
336 337 338 339 340 341 342 343
};

/*
 * The set of specific options for a tracer. Your tracer
 * have to set the initial value of the flags val.
 */
struct tracer_flags {
	u32			val;
I
Ingo Molnar 已提交
344
	struct tracer_opt	*opts;
345 346 347 348 349
};

/* Makes more easy to define a tracer opt */
#define TRACER_OPT(s, b)	.name = #s, .bit = b

350

351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368
/**
 * struct tracer - a specific tracer and its callbacks to interact with debugfs
 * @name: the name chosen to select it on the available_tracers file
 * @init: called when one switches to this tracer (echo name > current_tracer)
 * @reset: called when one switches to another tracer
 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 * @open: called when the trace file is opened
 * @pipe_open: called when the trace_pipe file is opened
 * @wait_pipe: override how the user waits for traces on trace_pipe
 * @close: called when the trace file is released
 * @read: override the default read callback on trace_pipe
 * @splice_read: override the default splice_read callback on trace_pipe
 * @selftest: selftest to run on boot (see trace_selftest.c)
 * @print_headers: override the first lines that describe your columns
 * @print_line: callback that prints a trace
 * @set_flag: signals one of your private flags changed (trace_options file)
 * @flags: your private flags
369 370 371
 */
struct tracer {
	const char		*name;
372
	int			(*init)(struct trace_array *tr);
373
	void			(*reset)(struct trace_array *tr);
374 375
	void			(*start)(struct trace_array *tr);
	void			(*stop)(struct trace_array *tr);
376
	void			(*open)(struct trace_iterator *iter);
377
	void			(*pipe_open)(struct trace_iterator *iter);
378
	void			(*wait_pipe)(struct trace_iterator *iter);
379
	void			(*close)(struct trace_iterator *iter);
380 381 382
	ssize_t			(*read)(struct trace_iterator *iter,
					struct file *filp, char __user *ubuf,
					size_t cnt, loff_t *ppos);
383 384 385 386 387 388
	ssize_t			(*splice_read)(struct trace_iterator *iter,
					       struct file *filp,
					       loff_t *ppos,
					       struct pipe_inode_info *pipe,
					       size_t len,
					       unsigned int flags);
S
Steven Rostedt 已提交
389 390 391 392
#ifdef CONFIG_FTRACE_STARTUP_TEST
	int			(*selftest)(struct tracer *trace,
					    struct trace_array *tr);
#endif
393
	void			(*print_header)(struct seq_file *m);
394
	enum print_line_t	(*print_line)(struct trace_iterator *iter);
395 396
	/* If you handled the flag setting, return 0 */
	int			(*set_flag)(u32 old_flags, u32 bit, int set);
397 398
	struct tracer		*next;
	int			print_max;
I
Ingo Molnar 已提交
399
	struct tracer_flags	*flags;
400
	struct tracer_stat	*stats;
401 402
};

S
Steven Rostedt 已提交
403 404 405
struct trace_seq {
	unsigned char		buffer[PAGE_SIZE];
	unsigned int		len;
406
	unsigned int		readpos;
S
Steven Rostedt 已提交
407 408
};

409 410 411 412 413 414 415 416
static inline void
trace_seq_init(struct trace_seq *s)
{
	s->len = 0;
	s->readpos = 0;
}


417 418
#define TRACE_PIPE_ALL_CPU	-1

419 420 421 422 423 424 425
/*
 * Trace iterator - used by printout routines who present trace
 * results to users and which routines might sleep, etc:
 */
struct trace_iterator {
	struct trace_array	*tr;
	struct tracer		*trace;
426
	void			*private;
427
	int			cpu_file;
428 429
	struct mutex		mutex;
	struct ring_buffer_iter	*buffer_iter[NR_CPUS];
I
Ingo Molnar 已提交
430

431 432
	/* The below is zeroed out in pipe_read */
	struct trace_seq	seq;
433
	struct trace_entry	*ent;
I
Ingo Molnar 已提交
434
	int			cpu;
435
	u64			ts;
I
Ingo Molnar 已提交
436

437 438
	unsigned long		iter_flags;
	loff_t			pos;
439
	long			idx;
440

441
	cpumask_var_t		started;
442 443
};

444
int tracer_init(struct tracer *t, struct trace_array *tr);
445
int tracing_is_enabled(void);
446
void trace_wake_up(void);
447
void tracing_reset(struct trace_array *tr, int cpu);
448
void tracing_reset_online_cpus(struct trace_array *tr);
449 450
int tracing_open_generic(struct inode *inode, struct file *filp);
struct dentry *tracing_init_dentry(void);
I
Ingo Molnar 已提交
451 452
void init_tracer_sysprof_debugfs(struct dentry *d_tracer);

453 454 455 456 457 458 459 460 461 462 463
struct ring_buffer_event;

struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
						    unsigned char type,
						    unsigned long len,
						    unsigned long flags,
						    int pc);
void trace_buffer_unlock_commit(struct trace_array *tr,
				struct ring_buffer_event *event,
				unsigned long flags, int pc);

464 465 466 467 468 469
struct ring_buffer_event *
trace_current_buffer_lock_reserve(unsigned char type, unsigned long len,
				  unsigned long flags, int pc);
void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
					unsigned long flags, int pc);

470 471
struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
						struct trace_array_cpu *data);
472 473 474 475

struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
					  int *ent_cpu, u64 *ent_ts);

476
void tracing_generic_entry_update(struct trace_entry *entry,
477 478
				  unsigned long flags,
				  int pc);
479

480 481 482
void default_wait_pipe(struct trace_iterator *iter);
void poll_wait_pipe(struct trace_iterator *iter);

483 484 485 486
void ftrace(struct trace_array *tr,
			    struct trace_array_cpu *data,
			    unsigned long ip,
			    unsigned long parent_ip,
487
			    unsigned long flags, int pc);
488 489 490
void tracing_sched_switch_trace(struct trace_array *tr,
				struct task_struct *prev,
				struct task_struct *next,
491
				unsigned long flags, int pc);
492
void tracing_record_cmdline(struct task_struct *tsk);
493 494 495 496

void tracing_sched_wakeup_trace(struct trace_array *tr,
				struct task_struct *wakee,
				struct task_struct *cur,
497
				unsigned long flags, int pc);
I
Ingo Molnar 已提交
498 499 500 501
void trace_special(struct trace_array *tr,
		   struct trace_array_cpu *data,
		   unsigned long arg1,
		   unsigned long arg2,
502
		   unsigned long arg3, int pc);
503 504 505
void trace_function(struct trace_array *tr,
		    unsigned long ip,
		    unsigned long parent_ip,
506
		    unsigned long flags, int pc);
507

508
void trace_graph_return(struct ftrace_graph_ret *trace);
509
int trace_graph_entry(struct ftrace_graph_ent *trace);
510

511 512
void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
S
Steven Rostedt 已提交
513 514 515
void tracing_sched_switch_assign_trace(struct trace_array *tr);
void tracing_stop_sched_switch_record(void);
void tracing_start_sched_switch_record(void);
516 517 518 519 520 521 522 523 524 525 526 527
int register_tracer(struct tracer *type);
void unregister_tracer(struct tracer *type);

extern unsigned long nsecs_to_usecs(unsigned long nsecs);

extern unsigned long tracing_max_latency;
extern unsigned long tracing_thresh;

void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
			  struct task_struct *tsk, int cpu);

528 529 530 531
void __trace_stack(struct trace_array *tr,
		   unsigned long flags,
		   int skip, int pc);

I
Ingo Molnar 已提交
532
extern cycle_t ftrace_now(int cpu);
533 534 535 536

#ifdef CONFIG_CONTEXT_SWITCH_TRACER
typedef void
(*tracer_switch_func_t)(void *private,
M
Mathieu Desnoyers 已提交
537
			void *__rq,
538 539 540 541 542 543 544 545 546 547
			struct task_struct *prev,
			struct task_struct *next);

struct tracer_switch_ops {
	tracer_switch_func_t		func;
	void				*private;
	struct tracer_switch_ops	*next;
};
#endif /* CONFIG_CONTEXT_SWITCH_TRACER */

548 549
extern char *trace_find_cmdline(int pid);

550 551
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
552 553
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
554 555
#endif

S
Steven Rostedt 已提交
556 557 558
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
					   struct trace_array *tr);
559 560
extern int trace_selftest_startup_function_graph(struct tracer *trace,
						 struct trace_array *tr);
S
Steven Rostedt 已提交
561 562 563 564 565 566 567 568
extern int trace_selftest_startup_irqsoff(struct tracer *trace,
					  struct trace_array *tr);
extern int trace_selftest_startup_preemptoff(struct tracer *trace,
					     struct trace_array *tr);
extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
						 struct trace_array *tr);
extern int trace_selftest_startup_wakeup(struct tracer *trace,
					 struct trace_array *tr);
S
Steven Noonan 已提交
569 570
extern int trace_selftest_startup_nop(struct tracer *trace,
					 struct trace_array *tr);
S
Steven Rostedt 已提交
571 572
extern int trace_selftest_startup_sched_switch(struct tracer *trace,
					       struct trace_array *tr);
573 574
extern int trace_selftest_startup_sysprof(struct tracer *trace,
					       struct trace_array *tr);
S
Steven Rostedt 已提交
575 576
extern int trace_selftest_startup_branch(struct tracer *trace,
					 struct trace_array *tr);
S
Steven Rostedt 已提交
577 578
#endif /* CONFIG_FTRACE_STARTUP_TEST */

I
Ingo Molnar 已提交
579
extern void *head_page(struct trace_array_cpu *data);
580
extern long ns2usecs(cycle_t nsec);
581
extern int
582 583
trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args);
extern int
584
trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args);
I
Ingo Molnar 已提交
585

586 587
extern unsigned long trace_flags;

588
/* Standard output formatting function used for function return traces */
589 590
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
extern enum print_line_t print_graph_function(struct trace_iterator *iter);
591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611

#ifdef CONFIG_DYNAMIC_FTRACE
/* TODO: make this variable */
#define FTRACE_GRAPH_MAX_FUNCS		32
extern int ftrace_graph_count;
extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];

static inline int ftrace_graph_addr(unsigned long addr)
{
	int i;

	if (!ftrace_graph_count || test_tsk_trace_graph(current))
		return 1;

	for (i = 0; i < ftrace_graph_count; i++) {
		if (addr == ftrace_graph_funcs[i])
			return 1;
	}

	return 0;
}
612
#else
613 614
static inline int ftrace_trace_addr(unsigned long addr)
{
615 616 617 618 619
	return 1;
}
static inline int ftrace_graph_addr(unsigned long addr)
{
	return 1;
620 621 622 623
}
#endif /* CONFIG_DYNAMIC_FTRACE */

#else /* CONFIG_FUNCTION_GRAPH_TRACER */
624
static inline enum print_line_t
625
print_graph_function(struct trace_iterator *iter)
626 627 628
{
	return TRACE_TYPE_UNHANDLED;
}
629
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
630

S
Steven Rostedt 已提交
631
extern struct pid *ftrace_pid_trace;
632 633 634

static inline int ftrace_trace_task(struct task_struct *task)
{
635
	if (!ftrace_pid_trace)
636 637 638 639 640
		return 1;

	return test_tsk_trace_trace(task);
}

S
Steven Rostedt 已提交
641 642 643 644 645 646 647
/*
 * trace_iterator_flags is an enumeration that defines bit
 * positions into trace_flags that controls the output.
 *
 * NOTE: These bits must match the trace_options array in
 *       trace.c.
 */
648 649 650 651 652 653 654 655 656 657
enum trace_iterator_flags {
	TRACE_ITER_PRINT_PARENT		= 0x01,
	TRACE_ITER_SYM_OFFSET		= 0x02,
	TRACE_ITER_SYM_ADDR		= 0x04,
	TRACE_ITER_VERBOSE		= 0x08,
	TRACE_ITER_RAW			= 0x10,
	TRACE_ITER_HEX			= 0x20,
	TRACE_ITER_BIN			= 0x40,
	TRACE_ITER_BLOCK		= 0x80,
	TRACE_ITER_STACKTRACE		= 0x100,
I
Ingo Molnar 已提交
658
	TRACE_ITER_SCHED_TREE		= 0x200,
659
	TRACE_ITER_PRINTK		= 0x400,
660
	TRACE_ITER_PREEMPTONLY		= 0x800,
661
	TRACE_ITER_BRANCH		= 0x1000,
662
	TRACE_ITER_ANNOTATE		= 0x2000,
663
	TRACE_ITER_USERSTACKTRACE       = 0x4000,
664
	TRACE_ITER_SYM_USEROBJ          = 0x8000,
665
	TRACE_ITER_PRINTK_MSGONLY	= 0x10000,
666 667
	TRACE_ITER_CONTEXT_INFO		= 0x20000, /* Print pid/cpu/time */
	TRACE_ITER_LATENCY_FMT		= 0x40000,
668 669
};

670 671 672 673 674 675 676
/*
 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 * control the output of kernel symbols.
 */
#define TRACE_ITER_SYM_MASK \
	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)

677 678
extern struct tracer nop_trace;

679 680 681 682 683 684 685 686 687
/**
 * ftrace_preempt_disable - disable preemption scheduler safe
 *
 * When tracing can happen inside the scheduler, there exists
 * cases that the tracing might happen before the need_resched
 * flag is checked. If this happens and the tracer calls
 * preempt_enable (after a disable), a schedule might take place
 * causing an infinite recursion.
 *
688
 * To prevent this, we read the need_resched flag before
689 690 691 692
 * disabling preemption. When we want to enable preemption we
 * check the flag, if it is set, then we call preempt_enable_no_resched.
 * Otherwise, we call preempt_enable.
 *
693
 * The rational for doing the above is that if need_resched is set
694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713
 * and we have yet to reschedule, we are either in an atomic location
 * (where we do not need to check for scheduling) or we are inside
 * the scheduler and do not want to resched.
 */
static inline int ftrace_preempt_disable(void)
{
	int resched;

	resched = need_resched();
	preempt_disable_notrace();

	return resched;
}

/**
 * ftrace_preempt_enable - enable preemption scheduler safe
 * @resched: the return value from ftrace_preempt_disable
 *
 * This is a scheduler safe way to enable preemption and not miss
 * any preemption checks. The disabled saved the state of preemption.
714
 * If resched is set, then we are either inside an atomic or
715 716 717 718 719 720 721 722 723 724 725 726
 * are inside the scheduler (we would have already scheduled
 * otherwise). In this case, we do not want to call normal
 * preempt_enable, but preempt_enable_no_resched instead.
 */
static inline void ftrace_preempt_enable(int resched)
{
	if (resched)
		preempt_enable_no_resched_notrace();
	else
		preempt_enable_notrace();
}

727
#ifdef CONFIG_BRANCH_TRACER
728 729 730
extern int enable_branch_tracing(struct trace_array *tr);
extern void disable_branch_tracing(void);
static inline int trace_branch_enable(struct trace_array *tr)
731
{
732 733
	if (trace_flags & TRACE_ITER_BRANCH)
		return enable_branch_tracing(tr);
734 735
	return 0;
}
736
static inline void trace_branch_disable(void)
737 738
{
	/* due to races, always disable */
739
	disable_branch_tracing();
740 741
}
#else
742
static inline int trace_branch_enable(struct trace_array *tr)
743 744 745
{
	return 0;
}
746
static inline void trace_branch_disable(void)
747 748
{
}
749
#endif /* CONFIG_BRANCH_TRACER */
750

751 752 753
/* set ring buffers to default size if not already done so */
int tracing_update_buffers(void);

754 755 756 757 758 759
/* trace event type bit fields, not numeric */
enum {
	TRACE_EVENT_TYPE_PRINTF		= 1,
	TRACE_EVENT_TYPE_RAW		= 2,
};

760 761 762 763 764 765 766 767 768
struct ftrace_event_call {
	char		*name;
	char		*system;
	struct dentry	*dir;
	int		enabled;
	int		(*regfunc)(void);
	void		(*unregfunc)(void);
	int		id;
	int		(*raw_init)(void);
769
	int		(*show_format)(struct trace_seq *s);
770 771 772 773 774 775
};

void event_trace_printk(unsigned long ip, const char *fmt, ...);
extern struct ftrace_event_call __start_ftrace_events[];
extern struct ftrace_event_call __stop_ftrace_events[];

776
#endif /* _LINUX_KERNEL_TRACE_H */