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 #ifdef CONFIG_DYNAMIC_FTRACE
99 /* asm/ftrace.h must be defined for archs supporting dynamic ftrace */
100 #include <asm/ftrace.h>
103 FTRACE_FL_FREE
= (1 << 0),
104 FTRACE_FL_FAILED
= (1 << 1),
105 FTRACE_FL_FILTER
= (1 << 2),
106 FTRACE_FL_ENABLED
= (1 << 3),
107 FTRACE_FL_NOTRACE
= (1 << 4),
108 FTRACE_FL_CONVERTED
= (1 << 5),
109 FTRACE_FL_FROZEN
= (1 << 6),
113 struct list_head list
;
114 unsigned long ip
; /* address of mcount call-site */
116 struct dyn_arch_ftrace arch
;
119 int ftrace_force_update(void);
120 void ftrace_set_filter(unsigned char *buf
, int len
, int reset
);
122 /* defined in arch */
123 extern int ftrace_ip_converted(unsigned long ip
);
124 extern int ftrace_dyn_arch_init(void *data
);
125 extern int ftrace_update_ftrace_func(ftrace_func_t func
);
126 extern void ftrace_caller(void);
127 extern void ftrace_call(void);
128 extern void mcount_call(void);
131 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
133 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
134 extern void ftrace_graph_caller(void);
135 extern int ftrace_enable_ftrace_graph_caller(void);
136 extern int ftrace_disable_ftrace_graph_caller(void);
138 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
139 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
143 * ftrace_make_nop - convert code into nop
144 * @mod: module structure if called by module load initialization
145 * @rec: the mcount call site record
146 * @addr: the address that the call site should be calling
148 * This is a very sensitive operation and great care needs
149 * to be taken by the arch. The operation should carefully
150 * read the location, check to see if what is read is indeed
151 * what we expect it to be, and then on success of the compare,
152 * it should write to the location.
154 * The code segment at @rec->ip should be a caller to @addr
158 * -EFAULT on error reading the location
159 * -EINVAL on a failed compare of the contents
160 * -EPERM on error writing to the location
161 * Any other value will be considered a failure.
163 extern int ftrace_make_nop(struct module
*mod
,
164 struct dyn_ftrace
*rec
, unsigned long addr
);
167 * ftrace_make_call - convert a nop call site into a call to addr
168 * @rec: the mcount call site record
169 * @addr: the address that the call site should call
171 * This is a very sensitive operation and great care needs
172 * to be taken by the arch. The operation should carefully
173 * read the location, check to see if what is read is indeed
174 * what we expect it to be, and then on success of the compare,
175 * it should write to the location.
177 * The code segment at @rec->ip should be a nop
181 * -EFAULT on error reading the location
182 * -EINVAL on a failed compare of the contents
183 * -EPERM on error writing to the location
184 * Any other value will be considered a failure.
186 extern int ftrace_make_call(struct dyn_ftrace
*rec
, unsigned long addr
);
189 /* May be defined in arch */
190 extern int ftrace_arch_read_dyn_info(char *buf
, int size
);
192 extern int skip_trace(unsigned long ip
);
194 extern void ftrace_release(void *start
, unsigned long size
);
196 extern void ftrace_disable_daemon(void);
197 extern void ftrace_enable_daemon(void);
199 # define skip_trace(ip) ({ 0; })
200 # define ftrace_force_update() ({ 0; })
201 # define ftrace_set_filter(buf, len, reset) do { } while (0)
202 # define ftrace_disable_daemon() do { } while (0)
203 # define ftrace_enable_daemon() do { } while (0)
204 static inline void ftrace_release(void *start
, unsigned long size
) { }
205 #endif /* CONFIG_DYNAMIC_FTRACE */
207 /* totally disable ftrace - can not re-enable after this */
208 void ftrace_kill(void);
210 static inline void tracer_disable(void)
212 #ifdef CONFIG_FUNCTION_TRACER
218 * Ftrace disable/restore without lock. Some synchronization mechanism
219 * must be used to prevent ftrace_enabled to be changed between
222 static inline int __ftrace_enabled_save(void)
224 #ifdef CONFIG_FUNCTION_TRACER
225 int saved_ftrace_enabled
= ftrace_enabled
;
227 return saved_ftrace_enabled
;
233 static inline void __ftrace_enabled_restore(int enabled
)
235 #ifdef CONFIG_FUNCTION_TRACER
236 ftrace_enabled
= enabled
;
240 #ifdef CONFIG_FRAME_POINTER
241 /* TODO: need to fix this for ARM */
242 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
243 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
244 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
245 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
246 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
247 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
248 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
250 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
251 # define CALLER_ADDR1 0UL
252 # define CALLER_ADDR2 0UL
253 # define CALLER_ADDR3 0UL
254 # define CALLER_ADDR4 0UL
255 # define CALLER_ADDR5 0UL
256 # define CALLER_ADDR6 0UL
259 #ifdef CONFIG_IRQSOFF_TRACER
260 extern void time_hardirqs_on(unsigned long a0
, unsigned long a1
);
261 extern void time_hardirqs_off(unsigned long a0
, unsigned long a1
);
263 # define time_hardirqs_on(a0, a1) do { } while (0)
264 # define time_hardirqs_off(a0, a1) do { } while (0)
267 #ifdef CONFIG_PREEMPT_TRACER
268 extern void trace_preempt_on(unsigned long a0
, unsigned long a1
);
269 extern void trace_preempt_off(unsigned long a0
, unsigned long a1
);
271 # define trace_preempt_on(a0, a1) do { } while (0)
272 # define trace_preempt_off(a0, a1) do { } while (0)
275 #ifdef CONFIG_TRACING
276 extern int ftrace_dump_on_oops
;
278 extern void tracing_start(void);
279 extern void tracing_stop(void);
280 extern void ftrace_off_permanent(void);
283 ftrace_special(unsigned long arg1
, unsigned long arg2
, unsigned long arg3
);
286 * ftrace_printk - printf formatting in the ftrace buffer
287 * @fmt: the printf format for printing
289 * Note: __ftrace_printk is an internal function for ftrace_printk and
290 * the @ip is passed in via the ftrace_printk macro.
292 * This function allows a kernel developer to debug fast path sections
293 * that printk is not appropriate for. By scattering in various
294 * printk like tracing in the code, a developer can quickly see
295 * where problems are occurring.
297 * This is intended as a debugging tool for the developer only.
298 * Please refrain from leaving ftrace_printks scattered around in
301 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
303 __ftrace_printk(unsigned long ip
, const char *fmt
, ...)
304 __attribute__ ((format (printf
, 2, 3)));
305 # define ftrace_vprintk(fmt, ap) __ftrace_printk(_THIS_IP_, fmt, ap)
307 __ftrace_vprintk(unsigned long ip
, const char *fmt
, va_list ap
);
308 extern void ftrace_dump(void);
311 ftrace_special(unsigned long arg1
, unsigned long arg2
, unsigned long arg3
) { }
313 ftrace_printk(const char *fmt
, ...) __attribute__ ((format (printf
, 1, 2)));
315 static inline void tracing_start(void) { }
316 static inline void tracing_stop(void) { }
317 static inline void ftrace_off_permanent(void) { }
319 ftrace_printk(const char *fmt
, ...)
324 ftrace_vprintk(const char *fmt
, va_list ap
)
328 static inline void ftrace_dump(void) { }
331 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
332 extern void ftrace_init(void);
333 extern void ftrace_init_module(struct module
*mod
,
334 unsigned long *start
, unsigned long *end
);
336 static inline void ftrace_init(void) { }
338 ftrace_init_module(struct module
*mod
,
339 unsigned long *start
, unsigned long *end
) { }
343 * Structure that defines an entry function trace.
345 struct ftrace_graph_ent
{
346 unsigned long func
; /* Current function */
351 * Structure that defines a return function trace.
353 struct ftrace_graph_ret
{
354 unsigned long func
; /* Current function */
355 unsigned long long calltime
;
356 unsigned long long rettime
;
357 /* Number of functions that overran the depth limit for current task */
358 unsigned long overrun
;
362 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
365 * Sometimes we don't want to trace a function with the function
366 * graph tracer but we want them to keep traced by the usual function
367 * tracer if the function graph tracer is not configured.
369 #define __notrace_funcgraph notrace
372 * We want to which function is an entrypoint of a hardirq.
373 * That will help us to put a signal on output.
375 #define __irq_entry __attribute__((__section__(".irqentry.text")))
377 /* Limits of hardirq entrypoints */
378 extern char __irqentry_text_start
[];
379 extern char __irqentry_text_end
[];
381 #define FTRACE_RETFUNC_DEPTH 50
382 #define FTRACE_RETSTACK_ALLOC_SIZE 32
383 /* Type of the callback handlers for tracing function graph*/
384 typedef void (*trace_func_graph_ret_t
)(struct ftrace_graph_ret
*); /* return */
385 typedef int (*trace_func_graph_ent_t
)(struct ftrace_graph_ent
*); /* entry */
387 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
388 trace_func_graph_ent_t entryfunc
);
390 extern void ftrace_graph_stop(void);
392 /* The current handlers in use */
393 extern trace_func_graph_ret_t ftrace_graph_return
;
394 extern trace_func_graph_ent_t ftrace_graph_entry
;
396 extern void unregister_ftrace_graph(void);
398 extern void ftrace_graph_init_task(struct task_struct
*t
);
399 extern void ftrace_graph_exit_task(struct task_struct
*t
);
401 static inline int task_curr_ret_stack(struct task_struct
*t
)
403 return t
->curr_ret_stack
;
406 static inline void pause_graph_tracing(void)
408 atomic_inc(¤t
->tracing_graph_pause
);
411 static inline void unpause_graph_tracing(void)
413 atomic_dec(¤t
->tracing_graph_pause
);
417 #define __notrace_funcgraph
420 static inline void ftrace_graph_init_task(struct task_struct
*t
) { }
421 static inline void ftrace_graph_exit_task(struct task_struct
*t
) { }
423 static inline int task_curr_ret_stack(struct task_struct
*tsk
)
428 static inline void pause_graph_tracing(void) { }
429 static inline void unpause_graph_tracing(void) { }
432 #ifdef CONFIG_TRACING
433 #include <linux/sched.h>
435 /* flags for current->trace */
437 TSK_TRACE_FL_TRACE_BIT
= 0,
438 TSK_TRACE_FL_GRAPH_BIT
= 1,
441 TSK_TRACE_FL_TRACE
= 1 << TSK_TRACE_FL_TRACE_BIT
,
442 TSK_TRACE_FL_GRAPH
= 1 << TSK_TRACE_FL_GRAPH_BIT
,
445 static inline void set_tsk_trace_trace(struct task_struct
*tsk
)
447 set_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
450 static inline void clear_tsk_trace_trace(struct task_struct
*tsk
)
452 clear_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
455 static inline int test_tsk_trace_trace(struct task_struct
*tsk
)
457 return tsk
->trace
& TSK_TRACE_FL_TRACE
;
460 static inline void set_tsk_trace_graph(struct task_struct
*tsk
)
462 set_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
465 static inline void clear_tsk_trace_graph(struct task_struct
*tsk
)
467 clear_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
470 static inline int test_tsk_trace_graph(struct task_struct
*tsk
)
472 return tsk
->trace
& TSK_TRACE_FL_GRAPH
;
475 #endif /* CONFIG_TRACING */
478 #ifdef CONFIG_HW_BRANCH_TRACER
480 void trace_hw_branch(u64 from
, u64 to
);
481 void trace_hw_branch_oops(void);
483 #else /* CONFIG_HW_BRANCH_TRACER */
485 static inline void trace_hw_branch(u64 from
, u64 to
) {}
486 static inline void trace_hw_branch_oops(void) {}
488 #endif /* CONFIG_HW_BRANCH_TRACER */
490 #endif /* _LINUX_FTRACE_H */