1 #ifndef _LINUX_FTRACE_H
2 #define _LINUX_FTRACE_H
4 #include <linux/linkage.h>
6 #include <linux/ktime.h>
7 #include <linux/init.h>
8 #include <linux/types.h>
9 #include <linux/module.h>
10 #include <linux/kallsyms.h>
11 #include <linux/bitops.h>
12 #include <linux/sched.h>
14 #ifdef CONFIG_FUNCTION_TRACER
16 extern int ftrace_enabled
;
18 ftrace_enable_sysctl(struct ctl_table
*table
, int write
,
19 struct file
*filp
, void __user
*buffer
, size_t *lenp
,
22 typedef void (*ftrace_func_t
)(unsigned long ip
, unsigned long parent_ip
);
26 struct ftrace_ops
*next
;
29 extern int function_trace_stop
;
32 * Type of the current tracing.
34 enum ftrace_tracing_type_t
{
35 FTRACE_TYPE_ENTER
= 0, /* Hook the call of the function */
36 FTRACE_TYPE_RETURN
, /* Hook the return of the function */
39 /* Current tracing type, default is FTRACE_TYPE_ENTER */
40 extern enum ftrace_tracing_type_t ftrace_tracing_type
;
43 * ftrace_stop - stop function tracer.
45 * A quick way to stop the function tracer. Note this an on off switch,
46 * it is not something that is recursive like preempt_disable.
47 * This does not disable the calling of mcount, it only stops the
48 * calling of functions from mcount.
50 static inline void ftrace_stop(void)
52 function_trace_stop
= 1;
56 * ftrace_start - start the function tracer.
58 * This function is the inverse of ftrace_stop. This does not enable
59 * the function tracing if the function tracer is disabled. This only
60 * sets the function tracer flag to continue calling the functions
63 static inline void ftrace_start(void)
65 function_trace_stop
= 0;
69 * The ftrace_ops must be a static and should also
70 * be read_mostly. These functions do modify read_mostly variables
71 * so use them sparely. Never free an ftrace_op or modify the
72 * next pointer after it has been registered. Even after unregistering
73 * it, the next pointer may still be used internally.
75 int register_ftrace_function(struct ftrace_ops
*ops
);
76 int unregister_ftrace_function(struct ftrace_ops
*ops
);
77 void clear_ftrace_function(void);
79 extern void ftrace_stub(unsigned long a0
, unsigned long a1
);
81 #else /* !CONFIG_FUNCTION_TRACER */
82 # define register_ftrace_function(ops) do { } while (0)
83 # define unregister_ftrace_function(ops) do { } while (0)
84 # define clear_ftrace_function(ops) do { } while (0)
85 static inline void ftrace_kill(void) { }
86 static inline void ftrace_stop(void) { }
87 static inline void ftrace_start(void) { }
88 #endif /* CONFIG_FUNCTION_TRACER */
90 #ifdef CONFIG_STACK_TRACER
91 extern int stack_tracer_enabled
;
93 stack_trace_sysctl(struct ctl_table
*table
, int write
,
94 struct file
*file
, void __user
*buffer
, size_t *lenp
,
98 struct ftrace_func_command
{
99 struct list_head list
;
101 int (*func
)(char *func
, char *cmd
,
102 char *params
, int enable
);
105 #ifdef CONFIG_DYNAMIC_FTRACE
106 /* asm/ftrace.h must be defined for archs supporting dynamic ftrace */
107 #include <asm/ftrace.h>
109 int ftrace_arch_code_modify_prepare(void);
110 int ftrace_arch_code_modify_post_process(void);
114 struct ftrace_probe_ops
{
115 void (*func
)(unsigned long ip
,
116 unsigned long parent_ip
,
118 int (*callback
)(unsigned long ip
, void **data
);
119 void (*free
)(void **data
);
120 int (*print
)(struct seq_file
*m
,
122 struct ftrace_probe_ops
*ops
,
127 register_ftrace_function_probe(char *glob
, struct ftrace_probe_ops
*ops
,
130 unregister_ftrace_function_probe(char *glob
, struct ftrace_probe_ops
*ops
,
133 unregister_ftrace_function_probe_func(char *glob
, struct ftrace_probe_ops
*ops
);
134 extern void unregister_ftrace_function_probe_all(char *glob
);
137 FTRACE_FL_FREE
= (1 << 0),
138 FTRACE_FL_FAILED
= (1 << 1),
139 FTRACE_FL_FILTER
= (1 << 2),
140 FTRACE_FL_ENABLED
= (1 << 3),
141 FTRACE_FL_NOTRACE
= (1 << 4),
142 FTRACE_FL_CONVERTED
= (1 << 5),
143 FTRACE_FL_FROZEN
= (1 << 6),
147 struct list_head list
;
148 unsigned long ip
; /* address of mcount call-site */
150 struct dyn_arch_ftrace arch
;
153 int ftrace_force_update(void);
154 void ftrace_set_filter(unsigned char *buf
, int len
, int reset
);
156 int register_ftrace_command(struct ftrace_func_command
*cmd
);
157 int unregister_ftrace_command(struct ftrace_func_command
*cmd
);
159 /* defined in arch */
160 extern int ftrace_ip_converted(unsigned long ip
);
161 extern int ftrace_dyn_arch_init(void *data
);
162 extern int ftrace_update_ftrace_func(ftrace_func_t func
);
163 extern void ftrace_caller(void);
164 extern void ftrace_call(void);
165 extern void mcount_call(void);
168 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
170 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
171 extern void ftrace_graph_caller(void);
172 extern int ftrace_enable_ftrace_graph_caller(void);
173 extern int ftrace_disable_ftrace_graph_caller(void);
175 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
176 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
180 * ftrace_make_nop - convert code into nop
181 * @mod: module structure if called by module load initialization
182 * @rec: the mcount call site record
183 * @addr: the address that the call site should be calling
185 * This is a very sensitive operation and great care needs
186 * to be taken by the arch. The operation should carefully
187 * read the location, check to see if what is read is indeed
188 * what we expect it to be, and then on success of the compare,
189 * it should write to the location.
191 * The code segment at @rec->ip should be a caller to @addr
195 * -EFAULT on error reading the location
196 * -EINVAL on a failed compare of the contents
197 * -EPERM on error writing to the location
198 * Any other value will be considered a failure.
200 extern int ftrace_make_nop(struct module
*mod
,
201 struct dyn_ftrace
*rec
, unsigned long addr
);
204 * ftrace_make_call - convert a nop call site into a call to addr
205 * @rec: the mcount call site record
206 * @addr: the address that the call site should call
208 * This is a very sensitive operation and great care needs
209 * to be taken by the arch. The operation should carefully
210 * read the location, check to see if what is read is indeed
211 * what we expect it to be, and then on success of the compare,
212 * it should write to the location.
214 * The code segment at @rec->ip should be a nop
218 * -EFAULT on error reading the location
219 * -EINVAL on a failed compare of the contents
220 * -EPERM on error writing to the location
221 * Any other value will be considered a failure.
223 extern int ftrace_make_call(struct dyn_ftrace
*rec
, unsigned long addr
);
226 /* May be defined in arch */
227 extern int ftrace_arch_read_dyn_info(char *buf
, int size
);
229 extern int skip_trace(unsigned long ip
);
231 extern void ftrace_release(void *start
, unsigned long size
);
233 extern void ftrace_disable_daemon(void);
234 extern void ftrace_enable_daemon(void);
236 # define skip_trace(ip) ({ 0; })
237 # define ftrace_force_update() ({ 0; })
238 # define ftrace_set_filter(buf, len, reset) do { } while (0)
239 # define ftrace_disable_daemon() do { } while (0)
240 # define ftrace_enable_daemon() do { } while (0)
241 static inline void ftrace_release(void *start
, unsigned long size
) { }
242 static inline int register_ftrace_command(struct ftrace_func_command
*cmd
)
246 static inline int unregister_ftrace_command(char *cmd_name
)
250 #endif /* CONFIG_DYNAMIC_FTRACE */
252 /* totally disable ftrace - can not re-enable after this */
253 void ftrace_kill(void);
255 static inline void tracer_disable(void)
257 #ifdef CONFIG_FUNCTION_TRACER
263 * Ftrace disable/restore without lock. Some synchronization mechanism
264 * must be used to prevent ftrace_enabled to be changed between
267 static inline int __ftrace_enabled_save(void)
269 #ifdef CONFIG_FUNCTION_TRACER
270 int saved_ftrace_enabled
= ftrace_enabled
;
272 return saved_ftrace_enabled
;
278 static inline void __ftrace_enabled_restore(int enabled
)
280 #ifdef CONFIG_FUNCTION_TRACER
281 ftrace_enabled
= enabled
;
285 #ifdef CONFIG_FRAME_POINTER
286 /* TODO: need to fix this for ARM */
287 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
288 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
289 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
290 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
291 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
292 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
293 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
295 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
296 # define CALLER_ADDR1 0UL
297 # define CALLER_ADDR2 0UL
298 # define CALLER_ADDR3 0UL
299 # define CALLER_ADDR4 0UL
300 # define CALLER_ADDR5 0UL
301 # define CALLER_ADDR6 0UL
304 #ifdef CONFIG_IRQSOFF_TRACER
305 extern void time_hardirqs_on(unsigned long a0
, unsigned long a1
);
306 extern void time_hardirqs_off(unsigned long a0
, unsigned long a1
);
308 # define time_hardirqs_on(a0, a1) do { } while (0)
309 # define time_hardirqs_off(a0, a1) do { } while (0)
312 #ifdef CONFIG_PREEMPT_TRACER
313 extern void trace_preempt_on(unsigned long a0
, unsigned long a1
);
314 extern void trace_preempt_off(unsigned long a0
, unsigned long a1
);
316 # define trace_preempt_on(a0, a1) do { } while (0)
317 # define trace_preempt_off(a0, a1) do { } while (0)
320 #ifdef CONFIG_TRACING
321 extern int ftrace_dump_on_oops
;
323 extern void tracing_start(void);
324 extern void tracing_stop(void);
325 extern void ftrace_off_permanent(void);
328 ftrace_special(unsigned long arg1
, unsigned long arg2
, unsigned long arg3
);
331 * ftrace_printk - printf formatting in the ftrace buffer
332 * @fmt: the printf format for printing
334 * Note: __ftrace_printk is an internal function for ftrace_printk and
335 * the @ip is passed in via the ftrace_printk macro.
337 * This function allows a kernel developer to debug fast path sections
338 * that printk is not appropriate for. By scattering in various
339 * printk like tracing in the code, a developer can quickly see
340 * where problems are occurring.
342 * This is intended as a debugging tool for the developer only.
343 * Please refrain from leaving ftrace_printks scattered around in
346 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
348 __ftrace_printk(unsigned long ip
, const char *fmt
, ...)
349 __attribute__ ((format (printf
, 2, 3)));
350 # define ftrace_vprintk(fmt, ap) __ftrace_printk(_THIS_IP_, fmt, ap)
352 __ftrace_vprintk(unsigned long ip
, const char *fmt
, va_list ap
);
353 extern void ftrace_dump(void);
356 ftrace_special(unsigned long arg1
, unsigned long arg2
, unsigned long arg3
) { }
358 ftrace_printk(const char *fmt
, ...) __attribute__ ((format (printf
, 1, 2)));
360 static inline void tracing_start(void) { }
361 static inline void tracing_stop(void) { }
362 static inline void ftrace_off_permanent(void) { }
364 ftrace_printk(const char *fmt
, ...)
369 ftrace_vprintk(const char *fmt
, va_list ap
)
373 static inline void ftrace_dump(void) { }
376 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
377 extern void ftrace_init(void);
378 extern void ftrace_init_module(struct module
*mod
,
379 unsigned long *start
, unsigned long *end
);
381 static inline void ftrace_init(void) { }
383 ftrace_init_module(struct module
*mod
,
384 unsigned long *start
, unsigned long *end
) { }
388 * Structure that defines an entry function trace.
390 struct ftrace_graph_ent
{
391 unsigned long func
; /* Current function */
396 * Structure that defines a return function trace.
398 struct ftrace_graph_ret
{
399 unsigned long func
; /* Current function */
400 unsigned long long calltime
;
401 unsigned long long rettime
;
402 /* Number of functions that overran the depth limit for current task */
403 unsigned long overrun
;
407 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
410 * Stack of return addresses for functions
412 * Used in struct thread_info
414 struct ftrace_ret_stack
{
417 unsigned long long calltime
;
421 * Primary handler of a function return.
422 * It relays on ftrace_return_to_handler.
423 * Defined in entry_32/64.S
425 extern void return_to_handler(void);
428 ftrace_push_return_trace(unsigned long ret
, unsigned long long time
,
429 unsigned long func
, int *depth
);
431 ftrace_pop_return_trace(struct ftrace_graph_ret
*trace
, unsigned long *ret
);
434 * Sometimes we don't want to trace a function with the function
435 * graph tracer but we want them to keep traced by the usual function
436 * tracer if the function graph tracer is not configured.
438 #define __notrace_funcgraph notrace
441 * We want to which function is an entrypoint of a hardirq.
442 * That will help us to put a signal on output.
444 #define __irq_entry __attribute__((__section__(".irqentry.text")))
446 /* Limits of hardirq entrypoints */
447 extern char __irqentry_text_start
[];
448 extern char __irqentry_text_end
[];
450 #define FTRACE_RETFUNC_DEPTH 50
451 #define FTRACE_RETSTACK_ALLOC_SIZE 32
452 /* Type of the callback handlers for tracing function graph*/
453 typedef void (*trace_func_graph_ret_t
)(struct ftrace_graph_ret
*); /* return */
454 typedef int (*trace_func_graph_ent_t
)(struct ftrace_graph_ent
*); /* entry */
456 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
457 trace_func_graph_ent_t entryfunc
);
459 extern void ftrace_graph_stop(void);
461 /* The current handlers in use */
462 extern trace_func_graph_ret_t ftrace_graph_return
;
463 extern trace_func_graph_ent_t ftrace_graph_entry
;
465 extern void unregister_ftrace_graph(void);
467 extern void ftrace_graph_init_task(struct task_struct
*t
);
468 extern void ftrace_graph_exit_task(struct task_struct
*t
);
470 static inline int task_curr_ret_stack(struct task_struct
*t
)
472 return t
->curr_ret_stack
;
475 static inline void pause_graph_tracing(void)
477 atomic_inc(¤t
->tracing_graph_pause
);
480 static inline void unpause_graph_tracing(void)
482 atomic_dec(¤t
->tracing_graph_pause
);
486 #define __notrace_funcgraph
489 static inline void ftrace_graph_init_task(struct task_struct
*t
) { }
490 static inline void ftrace_graph_exit_task(struct task_struct
*t
) { }
492 static inline int task_curr_ret_stack(struct task_struct
*tsk
)
497 static inline void pause_graph_tracing(void) { }
498 static inline void unpause_graph_tracing(void) { }
501 #ifdef CONFIG_TRACING
502 #include <linux/sched.h>
504 /* flags for current->trace */
506 TSK_TRACE_FL_TRACE_BIT
= 0,
507 TSK_TRACE_FL_GRAPH_BIT
= 1,
510 TSK_TRACE_FL_TRACE
= 1 << TSK_TRACE_FL_TRACE_BIT
,
511 TSK_TRACE_FL_GRAPH
= 1 << TSK_TRACE_FL_GRAPH_BIT
,
514 static inline void set_tsk_trace_trace(struct task_struct
*tsk
)
516 set_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
519 static inline void clear_tsk_trace_trace(struct task_struct
*tsk
)
521 clear_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
524 static inline int test_tsk_trace_trace(struct task_struct
*tsk
)
526 return tsk
->trace
& TSK_TRACE_FL_TRACE
;
529 static inline void set_tsk_trace_graph(struct task_struct
*tsk
)
531 set_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
534 static inline void clear_tsk_trace_graph(struct task_struct
*tsk
)
536 clear_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
539 static inline int test_tsk_trace_graph(struct task_struct
*tsk
)
541 return tsk
->trace
& TSK_TRACE_FL_GRAPH
;
544 #endif /* CONFIG_TRACING */
547 #ifdef CONFIG_HW_BRANCH_TRACER
549 void trace_hw_branch(u64 from
, u64 to
);
550 void trace_hw_branch_oops(void);
552 #else /* CONFIG_HW_BRANCH_TRACER */
554 static inline void trace_hw_branch(u64 from
, u64 to
) {}
555 static inline void trace_hw_branch_oops(void) {}
557 #endif /* CONFIG_HW_BRANCH_TRACER */
559 #endif /* _LINUX_FTRACE_H */