ftrace.h 24.7 KB
Newer Older
1
2
3
4
5
/*
 * Ftrace header.  For implementation details beyond the random comments
 * scattered below, see: Documentation/trace/ftrace-design.txt
 */

6
7
8
#ifndef _LINUX_FTRACE_H
#define _LINUX_FTRACE_H

9
#include <linux/trace_clock.h>
10
#include <linux/kallsyms.h>
11
#include <linux/linkage.h>
12
#include <linux/bitops.h>
13
#include <linux/ptrace.h>
14
#include <linux/ktime.h>
15
#include <linux/sched.h>
16
17
18
#include <linux/types.h>
#include <linux/init.h>
#include <linux/fs.h>
19

20
21
#include <asm/ftrace.h>

22
23
24
25
26
27
28
29
30
/*
 * If the arch supports passing the variable contents of
 * function_trace_op as the third parameter back from the
 * mcount call, then the arch should define this as 1.
 */
#ifndef ARCH_SUPPORTS_FTRACE_OPS
#define ARCH_SUPPORTS_FTRACE_OPS 0
#endif

31
32
33
34
35
36
37
38
39
40
41
42
43
/*
 * If the arch's mcount caller does not support all of ftrace's
 * features, then it must call an indirect function that
 * does. Or at least does enough to prevent any unwelcomed side effects.
 */
#if !defined(CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST) || \
	!ARCH_SUPPORTS_FTRACE_OPS
# define FTRACE_FORCE_LIST_FUNC 1
#else
# define FTRACE_FORCE_LIST_FUNC 0
#endif


44
struct module;
45
46
struct ftrace_hash;

47
#ifdef CONFIG_FUNCTION_TRACER
Ingo Molnar's avatar
Ingo Molnar committed
48

49
50
51
extern int ftrace_enabled;
extern int
ftrace_enable_sysctl(struct ctl_table *table, int write,
52
		     void __user *buffer, size_t *lenp,
53
54
		     loff_t *ppos);

55
56
57
struct ftrace_ops;

typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
58
			      struct ftrace_ops *op, struct pt_regs *regs);
59

60
61
62
63
64
65
66
67
68
69
70
71
72
73
/*
 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
 * set in the flags member.
 *
 * ENABLED - set/unset when ftrace_ops is registered/unregistered
 * GLOBAL  - set manualy by ftrace_ops user to denote the ftrace_ops
 *           is part of the global tracers sharing the same filter
 *           via set_ftrace_* debugfs files.
 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
 *           allocated ftrace_ops which need special care
 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
 *           could be controled by following calls:
 *             ftrace_function_local_enable
 *             ftrace_function_local_disable
74
75
76
77
78
79
80
81
82
83
84
85
86
87
 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
 *            and passed to the callback. If this flag is set, but the
 *            architecture does not support passing regs
 *            (ARCH_SUPPORTS_FTRACE_SAVE_REGS is not defined), then the
 *            ftrace_ops will fail to register, unless the next flag
 *            is set.
 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
 *            handler can handle an arch that does not save regs
 *            (the handler tests if regs == NULL), then it can set
 *            this flag instead. It will not fail registering the ftrace_ops
 *            but, the regs field will be NULL if the arch does not support
 *            passing regs to the handler.
 *            Note, if this flag is set, the SAVE_REGS flag will automatically
 *            get set upon registering the ftrace_ops, if the arch supports it.
88
 */
89
enum {
90
91
92
93
94
95
	FTRACE_OPS_FL_ENABLED			= 1 << 0,
	FTRACE_OPS_FL_GLOBAL			= 1 << 1,
	FTRACE_OPS_FL_DYNAMIC			= 1 << 2,
	FTRACE_OPS_FL_CONTROL			= 1 << 3,
	FTRACE_OPS_FL_SAVE_REGS			= 1 << 4,
	FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED	= 1 << 5,
96
97
};

98
struct ftrace_ops {
99
100
	ftrace_func_t			func;
	struct ftrace_ops		*next;
101
	unsigned long			flags;
102
	int __percpu			*disabled;
103
104
105
106
#ifdef CONFIG_DYNAMIC_FTRACE
	struct ftrace_hash		*notrace_hash;
	struct ftrace_hash		*filter_hash;
#endif
107
108
};

109
110
extern int function_trace_stop;

111
112
113
114
115
116
117
118
119
120
121
/*
 * Type of the current tracing.
 */
enum ftrace_tracing_type_t {
	FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
	FTRACE_TYPE_RETURN,	/* Hook the return of the function */
};

/* Current tracing type, default is FTRACE_TYPE_ENTER */
extern enum ftrace_tracing_type_t ftrace_tracing_type;

122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
/**
 * ftrace_stop - stop function tracer.
 *
 * A quick way to stop the function tracer. Note this an on off switch,
 * it is not something that is recursive like preempt_disable.
 * This does not disable the calling of mcount, it only stops the
 * calling of functions from mcount.
 */
static inline void ftrace_stop(void)
{
	function_trace_stop = 1;
}

/**
 * ftrace_start - start the function tracer.
 *
 * This function is the inverse of ftrace_stop. This does not enable
 * the function tracing if the function tracer is disabled. This only
 * sets the function tracer flag to continue calling the functions
 * from mcount.
 */
static inline void ftrace_start(void)
{
	function_trace_stop = 0;
}

148
149
150
151
152
153
154
155
156
157
158
/*
 * The ftrace_ops must be a static and should also
 * be read_mostly.  These functions do modify read_mostly variables
 * so use them sparely. Never free an ftrace_op or modify the
 * next pointer after it has been registered. Even after unregistering
 * it, the next pointer may still be used internally.
 */
int register_ftrace_function(struct ftrace_ops *ops);
int unregister_ftrace_function(struct ftrace_ops *ops);
void clear_ftrace_function(void);

159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/**
 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
 *
 * This function enables tracing on current cpu by decreasing
 * the per cpu control variable.
 * It must be called with preemption disabled and only on ftrace_ops
 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 */
static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
{
	if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
		return;

	(*this_cpu_ptr(ops->disabled))--;
}

/**
 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
 *
 * This function enables tracing on current cpu by decreasing
 * the per cpu control variable.
 * It must be called with preemption disabled and only on ftrace_ops
 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 */
static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
{
	if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
		return;

	(*this_cpu_ptr(ops->disabled))++;
}

/**
 * ftrace_function_local_disabled - returns ftrace_ops disabled value
 *                                  on current cpu
 *
 * This function returns value of ftrace_ops::disabled on current cpu.
 * It must be called with preemption disabled and only on ftrace_ops
 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 */
static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
{
	WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
	return *this_cpu_ptr(ops->disabled);
}

208
209
extern void ftrace_stub(unsigned long a0, unsigned long a1,
			struct ftrace_ops *op, struct pt_regs *regs);
210

211
#else /* !CONFIG_FUNCTION_TRACER */
212
213
214
215
216
217
218
/*
 * (un)register_ftrace_function must be a macro since the ops parameter
 * must not be evaluated.
 */
#define register_ftrace_function(ops) ({ 0; })
#define unregister_ftrace_function(ops) ({ 0; })
static inline void clear_ftrace_function(void) { }
219
static inline void ftrace_kill(void) { }
220
221
static inline void ftrace_stop(void) { }
static inline void ftrace_start(void) { }
222
#endif /* CONFIG_FUNCTION_TRACER */
223

224
225
226
227
#ifdef CONFIG_STACK_TRACER
extern int stack_tracer_enabled;
int
stack_trace_sysctl(struct ctl_table *table, int write,
228
		   void __user *buffer, size_t *lenp,
229
230
231
		   loff_t *ppos);
#endif

232
233
234
struct ftrace_func_command {
	struct list_head	list;
	char			*name;
235
236
	int			(*func)(struct ftrace_hash *hash,
					char *func, char *cmd,
237
238
239
					char *params, int enable);
};

240
#ifdef CONFIG_DYNAMIC_FTRACE
241

242
243
244
int ftrace_arch_code_modify_prepare(void);
int ftrace_arch_code_modify_post_process(void);

245
246
void ftrace_bug(int err, unsigned long ip);

247
248
struct seq_file;

249
struct ftrace_probe_ops {
250
251
252
253
254
	void			(*func)(unsigned long ip,
					unsigned long parent_ip,
					void **data);
	int			(*callback)(unsigned long ip, void **data);
	void			(*free)(void **data);
255
256
	int			(*print)(struct seq_file *m,
					 unsigned long ip,
257
					 struct ftrace_probe_ops *ops,
258
					 void *data);
259
260
261
};

extern int
262
register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
263
264
			      void *data);
extern void
265
unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
266
267
				void *data);
extern void
268
269
unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
extern void unregister_ftrace_function_probe_all(char *glob);
270

271
272
extern int ftrace_text_reserved(void *start, void *end);

273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
/*
 * The dyn_ftrace record's flags field is split into two parts.
 * the first part which is '0-FTRACE_REF_MAX' is a counter of
 * the number of callbacks that have registered the function that
 * the dyn_ftrace descriptor represents.
 *
 * The second part is a mask:
 *  ENABLED - the function is being traced
 *  REGS    - the record wants the function to save regs
 *  REGS_EN - the function is set up to save regs.
 *
 * When a new ftrace_ops is registered and wants a function to save
 * pt_regs, the rec->flag REGS is set. When the function has been
 * set up to save regs, the REG_EN flag is set. Once a function
 * starts saving regs it will do so until all ftrace_ops are removed
 * from tracing that function.
 */
290
enum {
291
292
293
	FTRACE_FL_ENABLED	= (1UL << 29),
	FTRACE_FL_REGS		= (1UL << 30),
	FTRACE_FL_REGS_EN	= (1UL << 31)
294
295
};

296
297
#define FTRACE_FL_MASK		(0x7UL << 29)
#define FTRACE_REF_MAX		((1UL << 29) - 1)
298

299
struct dyn_ftrace {
300
301
302
303
	union {
		unsigned long		ip; /* address of mcount call-site */
		struct dyn_ftrace	*freelist;
	};
304
	unsigned long		flags;
305
	struct dyn_arch_ftrace		arch;
306
307
};

Steven Rostedt's avatar
Steven Rostedt committed
308
int ftrace_force_update(void);
309
int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
310
		       int len, int reset);
311
int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
312
313
314
			int len, int reset);
void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
315
void ftrace_free_filter(struct ftrace_ops *ops);
Steven Rostedt's avatar
Steven Rostedt committed
316

317
318
319
int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);

320
321
322
323
324
325
326
327
enum {
	FTRACE_UPDATE_CALLS		= (1 << 0),
	FTRACE_DISABLE_CALLS		= (1 << 1),
	FTRACE_UPDATE_TRACE_FUNC	= (1 << 2),
	FTRACE_START_FUNC_RET		= (1 << 3),
	FTRACE_STOP_FUNC_RET		= (1 << 4),
};

328
329
330
331
332
333
334
335
336
337
338
339
/*
 * The FTRACE_UPDATE_* enum is used to pass information back
 * from the ftrace_update_record() and ftrace_test_record()
 * functions. These are called by the code update routines
 * to find out what is to be done for a given function.
 *
 *  IGNORE           - The function is already what we want it to be
 *  MAKE_CALL        - Start tracing the function
 *  MODIFY_CALL      - Stop saving regs for the function
 *  MODIFY_CALL_REGS - Start saving regs for the function
 *  MAKE_NOP         - Stop tracing the function
 */
340
341
342
enum {
	FTRACE_UPDATE_IGNORE,
	FTRACE_UPDATE_MAKE_CALL,
343
344
	FTRACE_UPDATE_MODIFY_CALL,
	FTRACE_UPDATE_MODIFY_CALL_REGS,
345
346
347
	FTRACE_UPDATE_MAKE_NOP,
};

348
349
350
351
enum {
	FTRACE_ITER_FILTER	= (1 << 0),
	FTRACE_ITER_NOTRACE	= (1 << 1),
	FTRACE_ITER_PRINTALL	= (1 << 2),
352
353
354
	FTRACE_ITER_DO_HASH	= (1 << 3),
	FTRACE_ITER_HASH	= (1 << 4),
	FTRACE_ITER_ENABLED	= (1 << 5),
355
356
};

357
358
359
360
361
362
363
364
void arch_ftrace_update_code(int command);

struct ftrace_rec_iter;

struct ftrace_rec_iter *ftrace_rec_iter_start(void);
struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);

365
366
367
368
369
370
#define for_ftrace_rec_iter(iter)		\
	for (iter = ftrace_rec_iter_start();	\
	     iter;				\
	     iter = ftrace_rec_iter_next(iter))


371
372
373
int ftrace_update_record(struct dyn_ftrace *rec, int enable);
int ftrace_test_record(struct dyn_ftrace *rec, int enable);
void ftrace_run_stop_machine(int command);
374
unsigned long ftrace_location(unsigned long ip);
375
376
377

extern ftrace_func_t ftrace_trace_function;

378
379
380
381
382
383
384
385
386
int ftrace_regex_open(struct ftrace_ops *ops, int flag,
		  struct inode *inode, struct file *file);
ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
			    size_t cnt, loff_t *ppos);
ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
			     size_t cnt, loff_t *ppos);
loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin);
int ftrace_regex_release(struct inode *inode, struct file *file);

387
388
389
void __init
ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);

390
/* defined in arch */
391
extern int ftrace_ip_converted(unsigned long ip);
392
extern int ftrace_dyn_arch_init(void *data);
393
extern void ftrace_replace_code(int enable);
394
395
extern int ftrace_update_ftrace_func(ftrace_func_t func);
extern void ftrace_caller(void);
396
extern void ftrace_regs_caller(void);
397
extern void ftrace_call(void);
398
extern void ftrace_regs_call(void);
399
extern void mcount_call(void);
400

401
402
void ftrace_modify_all_code(int command);

403
404
405
#ifndef FTRACE_ADDR
#define FTRACE_ADDR ((unsigned long)ftrace_caller)
#endif
406
407
408
409
410
411
412
413
414

#ifndef FTRACE_REGS_ADDR
#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
#else
# define FTRACE_REGS_ADDR FTRACE_ADDR
#endif
#endif

415
416
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
extern void ftrace_graph_caller(void);
417
418
419
420
421
extern int ftrace_enable_ftrace_graph_caller(void);
extern int ftrace_disable_ftrace_graph_caller(void);
#else
static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
422
#endif
423

424
/**
425
 * ftrace_make_nop - convert code into nop
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
 * @mod: module structure if called by module load initialization
 * @rec: the mcount call site record
 * @addr: the address that the call site should be calling
 *
 * This is a very sensitive operation and great care needs
 * to be taken by the arch.  The operation should carefully
 * read the location, check to see if what is read is indeed
 * what we expect it to be, and then on success of the compare,
 * it should write to the location.
 *
 * The code segment at @rec->ip should be a caller to @addr
 *
 * Return must be:
 *  0 on success
 *  -EFAULT on error reading the location
 *  -EINVAL on a failed compare of the contents
 *  -EPERM  on error writing to the location
 * Any other value will be considered a failure.
 */
extern int ftrace_make_nop(struct module *mod,
			   struct dyn_ftrace *rec, unsigned long addr);
447

448
/**
449
450
451
 * ftrace_make_call - convert a nop call site into a call to addr
 * @rec: the mcount call site record
 * @addr: the address that the call site should call
452
453
454
455
456
457
458
 *
 * This is a very sensitive operation and great care needs
 * to be taken by the arch.  The operation should carefully
 * read the location, check to see if what is read is indeed
 * what we expect it to be, and then on success of the compare,
 * it should write to the location.
 *
459
460
 * The code segment at @rec->ip should be a nop
 *
461
462
463
464
465
466
467
 * Return must be:
 *  0 on success
 *  -EFAULT on error reading the location
 *  -EINVAL on a failed compare of the contents
 *  -EPERM  on error writing to the location
 * Any other value will be considered a failure.
 */
468
469
extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);

470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
/**
 * ftrace_modify_call - convert from one addr to another (no nop)
 * @rec: the mcount call site record
 * @old_addr: the address expected to be currently called to
 * @addr: the address to change to
 *
 * This is a very sensitive operation and great care needs
 * to be taken by the arch.  The operation should carefully
 * read the location, check to see if what is read is indeed
 * what we expect it to be, and then on success of the compare,
 * it should write to the location.
 *
 * The code segment at @rec->ip should be a caller to @old_addr
 *
 * Return must be:
 *  0 on success
 *  -EFAULT on error reading the location
 *  -EINVAL on a failed compare of the contents
 *  -EPERM  on error writing to the location
 * Any other value will be considered a failure.
 */
extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
			      unsigned long addr);
#else
/* Should never be called */
static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
				     unsigned long addr)
{
	return -EINVAL;
}
#endif

503
504
/* May be defined in arch */
extern int ftrace_arch_read_dyn_info(char *buf, int size);
505

506
507
extern int skip_trace(unsigned long ip);

508
509
extern void ftrace_disable_daemon(void);
extern void ftrace_enable_daemon(void);
Steven Rostedt's avatar
Steven Rostedt committed
510
#else
511
512
513
514
static inline int skip_trace(unsigned long ip) { return 0; }
static inline int ftrace_force_update(void) { return 0; }
static inline void ftrace_disable_daemon(void) { }
static inline void ftrace_enable_daemon(void) { }
515
static inline void ftrace_release_mod(struct module *mod) {}
516
517
static inline int register_ftrace_command(struct ftrace_func_command *cmd)
{
518
	return -EINVAL;
519
520
521
}
static inline int unregister_ftrace_command(char *cmd_name)
{
522
	return -EINVAL;
523
}
524
525
526
527
static inline int ftrace_text_reserved(void *start, void *end)
{
	return 0;
}
528
529
530
531
532
533
534

/*
 * Again users of functions that have ftrace_ops may not
 * have them defined when ftrace is not enabled, but these
 * functions may still be called. Use a macro instead of inline.
 */
#define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
535
#define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
536
537
538
#define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
#define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
#define ftrace_free_filter(ops) do { } while (0)
539
540
541
542
543
544
545
546
547
548
549

static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
			    size_t cnt, loff_t *ppos) { return -ENODEV; }
static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
			     size_t cnt, loff_t *ppos) { return -ENODEV; }
static inline loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
{
	return -ENODEV;
}
static inline int
ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
550
#endif /* CONFIG_DYNAMIC_FTRACE */
551

Ingo Molnar's avatar
Ingo Molnar committed
552
553
554
/* totally disable ftrace - can not re-enable after this */
void ftrace_kill(void);

Ingo Molnar's avatar
Ingo Molnar committed
555
556
static inline void tracer_disable(void)
{
557
#ifdef CONFIG_FUNCTION_TRACER
Ingo Molnar's avatar
Ingo Molnar committed
558
559
560
561
	ftrace_enabled = 0;
#endif
}

562
563
/*
 * Ftrace disable/restore without lock. Some synchronization mechanism
564
 * must be used to prevent ftrace_enabled to be changed between
565
566
 * disable/restore.
 */
567
568
static inline int __ftrace_enabled_save(void)
{
569
#ifdef CONFIG_FUNCTION_TRACER
570
571
572
573
574
575
576
577
578
579
	int saved_ftrace_enabled = ftrace_enabled;
	ftrace_enabled = 0;
	return saved_ftrace_enabled;
#else
	return 0;
#endif
}

static inline void __ftrace_enabled_restore(int enabled)
{
580
#ifdef CONFIG_FUNCTION_TRACER
581
582
583
584
	ftrace_enabled = enabled;
#endif
}

585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
#ifndef HAVE_ARCH_CALLER_ADDR
# ifdef CONFIG_FRAME_POINTER
#  define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
#  define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
#  define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
#  define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
#  define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
#  define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
#  define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
# else
#  define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
#  define CALLER_ADDR1 0UL
#  define CALLER_ADDR2 0UL
#  define CALLER_ADDR3 0UL
#  define CALLER_ADDR4 0UL
#  define CALLER_ADDR5 0UL
#  define CALLER_ADDR6 0UL
# endif
#endif /* ifndef HAVE_ARCH_CALLER_ADDR */
604

605
#ifdef CONFIG_IRQSOFF_TRACER
Ingo Molnar's avatar
Ingo Molnar committed
606
607
  extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
  extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
608
#else
609
610
  static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
  static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
611
612
#endif

613
#ifdef CONFIG_PREEMPT_TRACER
Ingo Molnar's avatar
Ingo Molnar committed
614
615
  extern void trace_preempt_on(unsigned long a0, unsigned long a1);
  extern void trace_preempt_off(unsigned long a0, unsigned long a1);
616
#else
617
618
619
620
621
622
/*
 * Use defines instead of static inlines because some arches will make code out
 * of the CALLER_ADDR, when we really want these to be a real nop.
 */
# define trace_preempt_on(a0, a1) do { } while (0)
# define trace_preempt_off(a0, a1) do { } while (0)
623
624
#endif

625
626
627
628
629
630
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
extern void ftrace_init(void);
#else
static inline void ftrace_init(void) { }
#endif

631
632
633
634
635
636
637
/*
 * Structure that defines an entry function trace.
 */
struct ftrace_graph_ent {
	unsigned long func; /* Current function */
	int depth;
};
638

639
640
641
/*
 * Structure that defines a return function trace.
 */
642
struct ftrace_graph_ret {
643
644
645
	unsigned long func; /* Current function */
	unsigned long long calltime;
	unsigned long long rettime;
646
647
	/* Number of functions that overran the depth limit for current task */
	unsigned long overrun;
648
	int depth;
649
650
};

651
652
653
654
/* Type of the callback handlers for tracing function graph*/
typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */

655
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
656

657
/* for init task */
658
#define INIT_FTRACE_GRAPH		.ret_stack = NULL,
659

660
661
662
663
664
665
666
667
668
/*
 * Stack of return addresses for functions
 * of a thread.
 * Used in struct thread_info
 */
struct ftrace_ret_stack {
	unsigned long ret;
	unsigned long func;
	unsigned long long calltime;
669
	unsigned long long subtime;
670
	unsigned long fp;
671
672
673
674
675
676
677
678
679
680
};

/*
 * Primary handler of a function return.
 * It relays on ftrace_return_to_handler.
 * Defined in entry_32/64.S
 */
extern void return_to_handler(void);

extern int
681
682
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
			 unsigned long frame_pointer);
683

684
685
686
687
688
689
690
/*
 * Sometimes we don't want to trace a function with the function
 * graph tracer but we want them to keep traced by the usual function
 * tracer if the function graph tracer is not configured.
 */
#define __notrace_funcgraph		notrace

691
692
693
694
695
696
697
698
699
700
/*
 * We want to which function is an entrypoint of a hardirq.
 * That will help us to put a signal on output.
 */
#define __irq_entry		 __attribute__((__section__(".irqentry.text")))

/* Limits of hardirq entrypoints */
extern char __irqentry_text_start[];
extern char __irqentry_text_end[];

701
702
#define FTRACE_RETFUNC_DEPTH 50
#define FTRACE_RETSTACK_ALLOC_SIZE 32
703
704
705
extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
				trace_func_graph_ent_t entryfunc);

706
707
extern void ftrace_graph_stop(void);

708
709
710
/* The current handlers in use */
extern trace_func_graph_ret_t ftrace_graph_return;
extern trace_func_graph_ent_t ftrace_graph_entry;
711

712
extern void unregister_ftrace_graph(void);
713

714
715
extern void ftrace_graph_init_task(struct task_struct *t);
extern void ftrace_graph_exit_task(struct task_struct *t);
716
extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
717
718
719
720
721

static inline int task_curr_ret_stack(struct task_struct *t)
{
	return t->curr_ret_stack;
}
722
723
724
725
726
727
728
729
730
731

static inline void pause_graph_tracing(void)
{
	atomic_inc(&current->tracing_graph_pause);
}

static inline void unpause_graph_tracing(void)
{
	atomic_dec(&current->tracing_graph_pause);
}
732
#else /* !CONFIG_FUNCTION_GRAPH_TRACER */
733
734

#define __notrace_funcgraph
735
#define __irq_entry
736
#define INIT_FTRACE_GRAPH
737

738
739
static inline void ftrace_graph_init_task(struct task_struct *t) { }
static inline void ftrace_graph_exit_task(struct task_struct *t) { }
740
static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
741

742
743
744
745
746
747
748
static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
			  trace_func_graph_ent_t entryfunc)
{
	return -1;
}
static inline void unregister_ftrace_graph(void) { }

749
750
751
752
static inline int task_curr_ret_stack(struct task_struct *tsk)
{
	return -1;
}
753
754
755

static inline void pause_graph_tracing(void) { }
static inline void unpause_graph_tracing(void) { }
756
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
757

758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
#ifdef CONFIG_TRACING

/* flags for current->trace */
enum {
	TSK_TRACE_FL_TRACE_BIT	= 0,
	TSK_TRACE_FL_GRAPH_BIT	= 1,
};
enum {
	TSK_TRACE_FL_TRACE	= 1 << TSK_TRACE_FL_TRACE_BIT,
	TSK_TRACE_FL_GRAPH	= 1 << TSK_TRACE_FL_GRAPH_BIT,
};

static inline void set_tsk_trace_trace(struct task_struct *tsk)
{
	set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
}

static inline void clear_tsk_trace_trace(struct task_struct *tsk)
{
	clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
}

static inline int test_tsk_trace_trace(struct task_struct *tsk)
{
	return tsk->trace & TSK_TRACE_FL_TRACE;
}

static inline void set_tsk_trace_graph(struct task_struct *tsk)
{
	set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
}

static inline void clear_tsk_trace_graph(struct task_struct *tsk)
{
	clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
}

static inline int test_tsk_trace_graph(struct task_struct *tsk)
{
	return tsk->trace & TSK_TRACE_FL_GRAPH;
}

800
801
802
enum ftrace_dump_mode;

extern enum ftrace_dump_mode ftrace_dump_on_oops;
803

804
805
806
807
#ifdef CONFIG_PREEMPT
#define INIT_TRACE_RECURSION		.trace_recursion = 0,
#endif

808
809
#endif /* CONFIG_TRACING */

810
811
812
#ifndef INIT_TRACE_RECURSION
#define INIT_TRACE_RECURSION
#endif
813

814
815
816
817
818
819
#ifdef CONFIG_FTRACE_SYSCALLS

unsigned long arch_syscall_addr(int nr);

#endif /* CONFIG_FTRACE_SYSCALLS */

820
#endif /* _LINUX_FTRACE_H */