2 * Ftrace header. For implementation details beyond the random comments
3 * scattered below, see: Documentation/trace/ftrace-design.txt
6 #ifndef _LINUX_FTRACE_H
7 #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/ktime.h>
14 #include <linux/sched.h>
15 #include <linux/types.h>
16 #include <linux/init.h>
19 #include <asm/ftrace.h>
24 #ifdef CONFIG_FUNCTION_TRACER
26 extern int ftrace_enabled
;
28 ftrace_enable_sysctl(struct ctl_table
*table
, int write
,
29 void __user
*buffer
, size_t *lenp
,
32 typedef void (*ftrace_func_t
)(unsigned long ip
, unsigned long parent_ip
);
35 FTRACE_OPS_FL_ENABLED
= 1 << 0,
36 FTRACE_OPS_FL_GLOBAL
= 1 << 1,
37 FTRACE_OPS_FL_DYNAMIC
= 1 << 2,
42 struct ftrace_ops
*next
;
44 #ifdef CONFIG_DYNAMIC_FTRACE
45 struct ftrace_hash
*notrace_hash
;
46 struct ftrace_hash
*filter_hash
;
50 extern int function_trace_stop
;
53 * Type of the current tracing.
55 enum ftrace_tracing_type_t
{
56 FTRACE_TYPE_ENTER
= 0, /* Hook the call of the function */
57 FTRACE_TYPE_RETURN
, /* Hook the return of the function */
60 /* Current tracing type, default is FTRACE_TYPE_ENTER */
61 extern enum ftrace_tracing_type_t ftrace_tracing_type
;
64 * ftrace_stop - stop function tracer.
66 * A quick way to stop the function tracer. Note this an on off switch,
67 * it is not something that is recursive like preempt_disable.
68 * This does not disable the calling of mcount, it only stops the
69 * calling of functions from mcount.
71 static inline void ftrace_stop(void)
73 function_trace_stop
= 1;
77 * ftrace_start - start the function tracer.
79 * This function is the inverse of ftrace_stop. This does not enable
80 * the function tracing if the function tracer is disabled. This only
81 * sets the function tracer flag to continue calling the functions
84 static inline void ftrace_start(void)
86 function_trace_stop
= 0;
90 * The ftrace_ops must be a static and should also
91 * be read_mostly. These functions do modify read_mostly variables
92 * so use them sparely. Never free an ftrace_op or modify the
93 * next pointer after it has been registered. Even after unregistering
94 * it, the next pointer may still be used internally.
96 int register_ftrace_function(struct ftrace_ops
*ops
);
97 int unregister_ftrace_function(struct ftrace_ops
*ops
);
98 void clear_ftrace_function(void);
100 extern void ftrace_stub(unsigned long a0
, unsigned long a1
);
102 #else /* !CONFIG_FUNCTION_TRACER */
104 * (un)register_ftrace_function must be a macro since the ops parameter
105 * must not be evaluated.
107 #define register_ftrace_function(ops) ({ 0; })
108 #define unregister_ftrace_function(ops) ({ 0; })
109 static inline void clear_ftrace_function(void) { }
110 static inline void ftrace_kill(void) { }
111 static inline void ftrace_stop(void) { }
112 static inline void ftrace_start(void) { }
113 #endif /* CONFIG_FUNCTION_TRACER */
115 #ifdef CONFIG_STACK_TRACER
116 extern int stack_tracer_enabled
;
118 stack_trace_sysctl(struct ctl_table
*table
, int write
,
119 void __user
*buffer
, size_t *lenp
,
123 struct ftrace_func_command
{
124 struct list_head list
;
126 int (*func
)(struct ftrace_hash
*hash
,
127 char *func
, char *cmd
,
128 char *params
, int enable
);
131 #ifdef CONFIG_DYNAMIC_FTRACE
133 int ftrace_arch_code_modify_prepare(void);
134 int ftrace_arch_code_modify_post_process(void);
136 void ftrace_bug(int err
, unsigned long ip
);
140 struct ftrace_probe_ops
{
141 void (*func
)(unsigned long ip
,
142 unsigned long parent_ip
,
144 int (*callback
)(unsigned long ip
, void **data
);
145 void (*free
)(void **data
);
146 int (*print
)(struct seq_file
*m
,
148 struct ftrace_probe_ops
*ops
,
153 register_ftrace_function_probe(char *glob
, struct ftrace_probe_ops
*ops
,
156 unregister_ftrace_function_probe(char *glob
, struct ftrace_probe_ops
*ops
,
159 unregister_ftrace_function_probe_func(char *glob
, struct ftrace_probe_ops
*ops
);
160 extern void unregister_ftrace_function_probe_all(char *glob
);
162 extern int ftrace_text_reserved(void *start
, void *end
);
165 FTRACE_FL_ENABLED
= (1 << 30),
168 #define FTRACE_FL_MASK (0x3UL << 30)
169 #define FTRACE_REF_MAX ((1 << 30) - 1)
173 unsigned long ip
; /* address of mcount call-site */
174 struct dyn_ftrace
*freelist
;
177 struct dyn_arch_ftrace arch
;
180 int ftrace_force_update(void);
181 void ftrace_set_filter(struct ftrace_ops
*ops
, unsigned char *buf
,
183 void ftrace_set_notrace(struct ftrace_ops
*ops
, unsigned char *buf
,
185 void ftrace_set_global_filter(unsigned char *buf
, int len
, int reset
);
186 void ftrace_set_global_notrace(unsigned char *buf
, int len
, int reset
);
188 int register_ftrace_command(struct ftrace_func_command
*cmd
);
189 int unregister_ftrace_command(struct ftrace_func_command
*cmd
);
192 FTRACE_UPDATE_CALLS
= (1 << 0),
193 FTRACE_DISABLE_CALLS
= (1 << 1),
194 FTRACE_UPDATE_TRACE_FUNC
= (1 << 2),
195 FTRACE_START_FUNC_RET
= (1 << 3),
196 FTRACE_STOP_FUNC_RET
= (1 << 4),
200 FTRACE_UPDATE_IGNORE
,
201 FTRACE_UPDATE_MAKE_CALL
,
202 FTRACE_UPDATE_MAKE_NOP
,
206 FTRACE_ITER_FILTER
= (1 << 0),
207 FTRACE_ITER_NOTRACE
= (1 << 1),
208 FTRACE_ITER_PRINTALL
= (1 << 2),
209 FTRACE_ITER_DO_HASH
= (1 << 3),
210 FTRACE_ITER_HASH
= (1 << 4),
211 FTRACE_ITER_ENABLED
= (1 << 5),
214 void arch_ftrace_update_code(int command
);
216 struct ftrace_rec_iter
;
218 struct ftrace_rec_iter
*ftrace_rec_iter_start(void);
219 struct ftrace_rec_iter
*ftrace_rec_iter_next(struct ftrace_rec_iter
*iter
);
220 struct dyn_ftrace
*ftrace_rec_iter_record(struct ftrace_rec_iter
*iter
);
222 int ftrace_update_record(struct dyn_ftrace
*rec
, int enable
);
223 int ftrace_test_record(struct dyn_ftrace
*rec
, int enable
);
224 void ftrace_run_stop_machine(int command
);
225 int ftrace_location(unsigned long ip
);
227 extern ftrace_func_t ftrace_trace_function
;
229 int ftrace_regex_open(struct ftrace_ops
*ops
, int flag
,
230 struct inode
*inode
, struct file
*file
);
231 ssize_t
ftrace_filter_write(struct file
*file
, const char __user
*ubuf
,
232 size_t cnt
, loff_t
*ppos
);
233 ssize_t
ftrace_notrace_write(struct file
*file
, const char __user
*ubuf
,
234 size_t cnt
, loff_t
*ppos
);
235 loff_t
ftrace_regex_lseek(struct file
*file
, loff_t offset
, int origin
);
236 int ftrace_regex_release(struct inode
*inode
, struct file
*file
);
238 /* defined in arch */
239 extern int ftrace_ip_converted(unsigned long ip
);
240 extern int ftrace_dyn_arch_init(void *data
);
241 extern int ftrace_update_ftrace_func(ftrace_func_t func
);
242 extern void ftrace_caller(void);
243 extern void ftrace_call(void);
244 extern void mcount_call(void);
247 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
249 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
250 extern void ftrace_graph_caller(void);
251 extern int ftrace_enable_ftrace_graph_caller(void);
252 extern int ftrace_disable_ftrace_graph_caller(void);
254 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
255 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
259 * ftrace_make_nop - convert code into nop
260 * @mod: module structure if called by module load initialization
261 * @rec: the mcount call site record
262 * @addr: the address that the call site should be calling
264 * This is a very sensitive operation and great care needs
265 * to be taken by the arch. The operation should carefully
266 * read the location, check to see if what is read is indeed
267 * what we expect it to be, and then on success of the compare,
268 * it should write to the location.
270 * The code segment at @rec->ip should be a caller to @addr
274 * -EFAULT on error reading the location
275 * -EINVAL on a failed compare of the contents
276 * -EPERM on error writing to the location
277 * Any other value will be considered a failure.
279 extern int ftrace_make_nop(struct module
*mod
,
280 struct dyn_ftrace
*rec
, unsigned long addr
);
283 * ftrace_make_call - convert a nop call site into a call to addr
284 * @rec: the mcount call site record
285 * @addr: the address that the call site should call
287 * This is a very sensitive operation and great care needs
288 * to be taken by the arch. The operation should carefully
289 * read the location, check to see if what is read is indeed
290 * what we expect it to be, and then on success of the compare,
291 * it should write to the location.
293 * The code segment at @rec->ip should be a nop
297 * -EFAULT on error reading the location
298 * -EINVAL on a failed compare of the contents
299 * -EPERM on error writing to the location
300 * Any other value will be considered a failure.
302 extern int ftrace_make_call(struct dyn_ftrace
*rec
, unsigned long addr
);
304 /* May be defined in arch */
305 extern int ftrace_arch_read_dyn_info(char *buf
, int size
);
307 extern int skip_trace(unsigned long ip
);
309 extern void ftrace_disable_daemon(void);
310 extern void ftrace_enable_daemon(void);
312 static inline int skip_trace(unsigned long ip
) { return 0; }
313 static inline int ftrace_force_update(void) { return 0; }
314 static inline void ftrace_set_filter(unsigned char *buf
, int len
, int reset
)
317 static inline void ftrace_disable_daemon(void) { }
318 static inline void ftrace_enable_daemon(void) { }
319 static inline void ftrace_release_mod(struct module
*mod
) {}
320 static inline int register_ftrace_command(struct ftrace_func_command
*cmd
)
324 static inline int unregister_ftrace_command(char *cmd_name
)
328 static inline int ftrace_text_reserved(void *start
, void *end
)
334 * Again users of functions that have ftrace_ops may not
335 * have them defined when ftrace is not enabled, but these
336 * functions may still be called. Use a macro instead of inline.
338 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
340 static inline ssize_t
ftrace_filter_write(struct file
*file
, const char __user
*ubuf
,
341 size_t cnt
, loff_t
*ppos
) { return -ENODEV
; }
342 static inline ssize_t
ftrace_notrace_write(struct file
*file
, const char __user
*ubuf
,
343 size_t cnt
, loff_t
*ppos
) { return -ENODEV
; }
344 static inline loff_t
ftrace_regex_lseek(struct file
*file
, loff_t offset
, int origin
)
349 ftrace_regex_release(struct inode
*inode
, struct file
*file
) { return -ENODEV
; }
350 #endif /* CONFIG_DYNAMIC_FTRACE */
352 /* totally disable ftrace - can not re-enable after this */
353 void ftrace_kill(void);
355 static inline void tracer_disable(void)
357 #ifdef CONFIG_FUNCTION_TRACER
363 * Ftrace disable/restore without lock. Some synchronization mechanism
364 * must be used to prevent ftrace_enabled to be changed between
367 static inline int __ftrace_enabled_save(void)
369 #ifdef CONFIG_FUNCTION_TRACER
370 int saved_ftrace_enabled
= ftrace_enabled
;
372 return saved_ftrace_enabled
;
378 static inline void __ftrace_enabled_restore(int enabled
)
380 #ifdef CONFIG_FUNCTION_TRACER
381 ftrace_enabled
= enabled
;
385 #ifndef HAVE_ARCH_CALLER_ADDR
386 # ifdef CONFIG_FRAME_POINTER
387 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
388 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
389 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
390 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
391 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
392 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
393 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
395 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
396 # define CALLER_ADDR1 0UL
397 # define CALLER_ADDR2 0UL
398 # define CALLER_ADDR3 0UL
399 # define CALLER_ADDR4 0UL
400 # define CALLER_ADDR5 0UL
401 # define CALLER_ADDR6 0UL
403 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
405 #ifdef CONFIG_IRQSOFF_TRACER
406 extern void time_hardirqs_on(unsigned long a0
, unsigned long a1
);
407 extern void time_hardirqs_off(unsigned long a0
, unsigned long a1
);
409 static inline void time_hardirqs_on(unsigned long a0
, unsigned long a1
) { }
410 static inline void time_hardirqs_off(unsigned long a0
, unsigned long a1
) { }
413 #ifdef CONFIG_PREEMPT_TRACER
414 extern void trace_preempt_on(unsigned long a0
, unsigned long a1
);
415 extern void trace_preempt_off(unsigned long a0
, unsigned long a1
);
417 static inline void trace_preempt_on(unsigned long a0
, unsigned long a1
) { }
418 static inline void trace_preempt_off(unsigned long a0
, unsigned long a1
) { }
421 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
422 extern void ftrace_init(void);
424 static inline void ftrace_init(void) { }
428 * Structure that defines an entry function trace.
430 struct ftrace_graph_ent
{
431 unsigned long func
; /* Current function */
436 * Structure that defines a return function trace.
438 struct ftrace_graph_ret
{
439 unsigned long func
; /* Current function */
440 unsigned long long calltime
;
441 unsigned long long rettime
;
442 /* Number of functions that overran the depth limit for current task */
443 unsigned long overrun
;
447 /* Type of the callback handlers for tracing function graph*/
448 typedef void (*trace_func_graph_ret_t
)(struct ftrace_graph_ret
*); /* return */
449 typedef int (*trace_func_graph_ent_t
)(struct ftrace_graph_ent
*); /* entry */
451 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
454 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
457 * Stack of return addresses for functions
459 * Used in struct thread_info
461 struct ftrace_ret_stack
{
464 unsigned long long calltime
;
465 unsigned long long subtime
;
470 * Primary handler of a function return.
471 * It relays on ftrace_return_to_handler.
472 * Defined in entry_32/64.S
474 extern void return_to_handler(void);
477 ftrace_push_return_trace(unsigned long ret
, unsigned long func
, int *depth
,
478 unsigned long frame_pointer
);
481 * Sometimes we don't want to trace a function with the function
482 * graph tracer but we want them to keep traced by the usual function
483 * tracer if the function graph tracer is not configured.
485 #define __notrace_funcgraph notrace
488 * We want to which function is an entrypoint of a hardirq.
489 * That will help us to put a signal on output.
491 #define __irq_entry __attribute__((__section__(".irqentry.text")))
493 /* Limits of hardirq entrypoints */
494 extern char __irqentry_text_start
[];
495 extern char __irqentry_text_end
[];
497 #define FTRACE_RETFUNC_DEPTH 50
498 #define FTRACE_RETSTACK_ALLOC_SIZE 32
499 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
500 trace_func_graph_ent_t entryfunc
);
502 extern void ftrace_graph_stop(void);
504 /* The current handlers in use */
505 extern trace_func_graph_ret_t ftrace_graph_return
;
506 extern trace_func_graph_ent_t ftrace_graph_entry
;
508 extern void unregister_ftrace_graph(void);
510 extern void ftrace_graph_init_task(struct task_struct
*t
);
511 extern void ftrace_graph_exit_task(struct task_struct
*t
);
512 extern void ftrace_graph_init_idle_task(struct task_struct
*t
, int cpu
);
514 static inline int task_curr_ret_stack(struct task_struct
*t
)
516 return t
->curr_ret_stack
;
519 static inline void pause_graph_tracing(void)
521 atomic_inc(¤t
->tracing_graph_pause
);
524 static inline void unpause_graph_tracing(void)
526 atomic_dec(¤t
->tracing_graph_pause
);
528 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
530 #define __notrace_funcgraph
532 #define INIT_FTRACE_GRAPH
534 static inline void ftrace_graph_init_task(struct task_struct
*t
) { }
535 static inline void ftrace_graph_exit_task(struct task_struct
*t
) { }
536 static inline void ftrace_graph_init_idle_task(struct task_struct
*t
, int cpu
) { }
538 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
539 trace_func_graph_ent_t entryfunc
)
543 static inline void unregister_ftrace_graph(void) { }
545 static inline int task_curr_ret_stack(struct task_struct
*tsk
)
550 static inline void pause_graph_tracing(void) { }
551 static inline void unpause_graph_tracing(void) { }
552 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
554 #ifdef CONFIG_TRACING
556 /* flags for current->trace */
558 TSK_TRACE_FL_TRACE_BIT
= 0,
559 TSK_TRACE_FL_GRAPH_BIT
= 1,
562 TSK_TRACE_FL_TRACE
= 1 << TSK_TRACE_FL_TRACE_BIT
,
563 TSK_TRACE_FL_GRAPH
= 1 << TSK_TRACE_FL_GRAPH_BIT
,
566 static inline void set_tsk_trace_trace(struct task_struct
*tsk
)
568 set_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
571 static inline void clear_tsk_trace_trace(struct task_struct
*tsk
)
573 clear_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
576 static inline int test_tsk_trace_trace(struct task_struct
*tsk
)
578 return tsk
->trace
& TSK_TRACE_FL_TRACE
;
581 static inline void set_tsk_trace_graph(struct task_struct
*tsk
)
583 set_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
586 static inline void clear_tsk_trace_graph(struct task_struct
*tsk
)
588 clear_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
591 static inline int test_tsk_trace_graph(struct task_struct
*tsk
)
593 return tsk
->trace
& TSK_TRACE_FL_GRAPH
;
596 enum ftrace_dump_mode
;
598 extern enum ftrace_dump_mode ftrace_dump_on_oops
;
600 #ifdef CONFIG_PREEMPT
601 #define INIT_TRACE_RECURSION .trace_recursion = 0,
604 #endif /* CONFIG_TRACING */
606 #ifndef INIT_TRACE_RECURSION
607 #define INIT_TRACE_RECURSION
610 #ifdef CONFIG_FTRACE_SYSCALLS
612 unsigned long arch_syscall_addr(int nr
);
614 #endif /* CONFIG_FTRACE_SYSCALLS */
616 #endif /* _LINUX_FTRACE_H */