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>
111 struct ftrace_hook_ops {
112 void (*func)(unsigned long ip,
113 unsigned long parent_ip,
115 int (*callback)(unsigned long ip, void **data);
116 void (*free)(void **data);
117 int (*print)(struct seq_file *m,
119 struct ftrace_hook_ops *ops,
124 register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
127 unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
130 unregister_ftrace_function_hook_func(char *glob, struct ftrace_hook_ops *ops);
131 extern void unregister_ftrace_function_hook_all(char *glob);
134 FTRACE_FL_FREE = (1 << 0),
135 FTRACE_FL_FAILED = (1 << 1),
136 FTRACE_FL_FILTER = (1 << 2),
137 FTRACE_FL_ENABLED = (1 << 3),
138 FTRACE_FL_NOTRACE = (1 << 4),
139 FTRACE_FL_CONVERTED = (1 << 5),
140 FTRACE_FL_FROZEN = (1 << 6),
144 struct list_head list;
145 unsigned long ip; /* address of mcount call-site */
147 struct dyn_arch_ftrace arch;
150 int ftrace_force_update(void);
151 void ftrace_set_filter(unsigned char *buf, int len, int reset);
153 int register_ftrace_command(struct ftrace_func_command *cmd);
154 int unregister_ftrace_command(struct ftrace_func_command *cmd);
156 /* defined in arch */
157 extern int ftrace_ip_converted(unsigned long ip);
158 extern int ftrace_dyn_arch_init(void *data);
159 extern int ftrace_update_ftrace_func(ftrace_func_t func);
160 extern void ftrace_caller(void);
161 extern void ftrace_call(void);
162 extern void mcount_call(void);
165 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
167 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
168 extern void ftrace_graph_caller(void);
169 extern int ftrace_enable_ftrace_graph_caller(void);
170 extern int ftrace_disable_ftrace_graph_caller(void);
172 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
173 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
177 * ftrace_make_nop - convert code into nop
178 * @mod: module structure if called by module load initialization
179 * @rec: the mcount call site record
180 * @addr: the address that the call site should be calling
182 * This is a very sensitive operation and great care needs
183 * to be taken by the arch. The operation should carefully
184 * read the location, check to see if what is read is indeed
185 * what we expect it to be, and then on success of the compare,
186 * it should write to the location.
188 * The code segment at @rec->ip should be a caller to @addr
192 * -EFAULT on error reading the location
193 * -EINVAL on a failed compare of the contents
194 * -EPERM on error writing to the location
195 * Any other value will be considered a failure.
197 extern int ftrace_make_nop(struct module *mod,
198 struct dyn_ftrace *rec, unsigned long addr);
201 * ftrace_make_call - convert a nop call site into a call to addr
202 * @rec: the mcount call site record
203 * @addr: the address that the call site should call
205 * This is a very sensitive operation and great care needs
206 * to be taken by the arch. The operation should carefully
207 * read the location, check to see if what is read is indeed
208 * what we expect it to be, and then on success of the compare,
209 * it should write to the location.
211 * The code segment at @rec->ip should be a nop
215 * -EFAULT on error reading the location
216 * -EINVAL on a failed compare of the contents
217 * -EPERM on error writing to the location
218 * Any other value will be considered a failure.
220 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
223 /* May be defined in arch */
224 extern int ftrace_arch_read_dyn_info(char *buf, int size);
226 extern int skip_trace(unsigned long ip);
228 extern void ftrace_release(void *start, unsigned long size);
230 extern void ftrace_disable_daemon(void);
231 extern void ftrace_enable_daemon(void);
233 # define skip_trace(ip) ({ 0; })
234 # define ftrace_force_update() ({ 0; })
235 # define ftrace_set_filter(buf, len, reset) do { } while (0)
236 # define ftrace_disable_daemon() do { } while (0)
237 # define ftrace_enable_daemon() do { } while (0)
238 static inline void ftrace_release(void *start, unsigned long size) { }
239 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
242 static inline int unregister_ftrace_command(char *cmd_name)
245 #endif /* CONFIG_DYNAMIC_FTRACE */
247 /* totally disable ftrace - can not re-enable after this */
248 void ftrace_kill(void);
250 static inline void tracer_disable(void)
252 #ifdef CONFIG_FUNCTION_TRACER
258 * Ftrace disable/restore without lock. Some synchronization mechanism
259 * must be used to prevent ftrace_enabled to be changed between
262 static inline int __ftrace_enabled_save(void)
264 #ifdef CONFIG_FUNCTION_TRACER
265 int saved_ftrace_enabled = ftrace_enabled;
267 return saved_ftrace_enabled;
273 static inline void __ftrace_enabled_restore(int enabled)
275 #ifdef CONFIG_FUNCTION_TRACER
276 ftrace_enabled = enabled;
280 #ifdef CONFIG_FRAME_POINTER
281 /* TODO: need to fix this for ARM */
282 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
283 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
284 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
285 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
286 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
287 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
288 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
290 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
291 # define CALLER_ADDR1 0UL
292 # define CALLER_ADDR2 0UL
293 # define CALLER_ADDR3 0UL
294 # define CALLER_ADDR4 0UL
295 # define CALLER_ADDR5 0UL
296 # define CALLER_ADDR6 0UL
299 #ifdef CONFIG_IRQSOFF_TRACER
300 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
301 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
303 # define time_hardirqs_on(a0, a1) do { } while (0)
304 # define time_hardirqs_off(a0, a1) do { } while (0)
307 #ifdef CONFIG_PREEMPT_TRACER
308 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
309 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
311 # define trace_preempt_on(a0, a1) do { } while (0)
312 # define trace_preempt_off(a0, a1) do { } while (0)
315 #ifdef CONFIG_TRACING
316 extern int ftrace_dump_on_oops;
318 extern void tracing_start(void);
319 extern void tracing_stop(void);
320 extern void ftrace_off_permanent(void);
323 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
326 * ftrace_printk - printf formatting in the ftrace buffer
327 * @fmt: the printf format for printing
329 * Note: __ftrace_printk is an internal function for ftrace_printk and
330 * the @ip is passed in via the ftrace_printk macro.
332 * This function allows a kernel developer to debug fast path sections
333 * that printk is not appropriate for. By scattering in various
334 * printk like tracing in the code, a developer can quickly see
335 * where problems are occurring.
337 * This is intended as a debugging tool for the developer only.
338 * Please refrain from leaving ftrace_printks scattered around in
341 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
343 __ftrace_printk(unsigned long ip, const char *fmt, ...)
344 __attribute__ ((format (printf, 2, 3)));
345 # define ftrace_vprintk(fmt, ap) __ftrace_printk(_THIS_IP_, fmt, ap)
347 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
348 extern void ftrace_dump(void);
351 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
353 ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
355 static inline void tracing_start(void) { }
356 static inline void tracing_stop(void) { }
357 static inline void ftrace_off_permanent(void) { }
359 ftrace_printk(const char *fmt, ...)
364 ftrace_vprintk(const char *fmt, va_list ap)
368 static inline void ftrace_dump(void) { }
371 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
372 extern void ftrace_init(void);
373 extern void ftrace_init_module(struct module *mod,
374 unsigned long *start, unsigned long *end);
376 static inline void ftrace_init(void) { }
378 ftrace_init_module(struct module *mod,
379 unsigned long *start, unsigned long *end) { }
383 * Structure that defines an entry function trace.
385 struct ftrace_graph_ent {
386 unsigned long func; /* Current function */
391 * Structure that defines a return function trace.
393 struct ftrace_graph_ret {
394 unsigned long func; /* Current function */
395 unsigned long long calltime;
396 unsigned long long rettime;
397 /* Number of functions that overran the depth limit for current task */
398 unsigned long overrun;
402 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
405 * Sometimes we don't want to trace a function with the function
406 * graph tracer but we want them to keep traced by the usual function
407 * tracer if the function graph tracer is not configured.
409 #define __notrace_funcgraph notrace
412 * We want to which function is an entrypoint of a hardirq.
413 * That will help us to put a signal on output.
415 #define __irq_entry __attribute__((__section__(".irqentry.text")))
417 /* Limits of hardirq entrypoints */
418 extern char __irqentry_text_start[];
419 extern char __irqentry_text_end[];
421 #define FTRACE_RETFUNC_DEPTH 50
422 #define FTRACE_RETSTACK_ALLOC_SIZE 32
423 /* Type of the callback handlers for tracing function graph*/
424 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
425 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
427 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
428 trace_func_graph_ent_t entryfunc);
430 extern void ftrace_graph_stop(void);
432 /* The current handlers in use */
433 extern trace_func_graph_ret_t ftrace_graph_return;
434 extern trace_func_graph_ent_t ftrace_graph_entry;
436 extern void unregister_ftrace_graph(void);
438 extern void ftrace_graph_init_task(struct task_struct *t);
439 extern void ftrace_graph_exit_task(struct task_struct *t);
441 static inline int task_curr_ret_stack(struct task_struct *t)
443 return t->curr_ret_stack;
446 static inline void pause_graph_tracing(void)
448 atomic_inc(¤t->tracing_graph_pause);
451 static inline void unpause_graph_tracing(void)
453 atomic_dec(¤t->tracing_graph_pause);
457 #define __notrace_funcgraph
460 static inline void ftrace_graph_init_task(struct task_struct *t) { }
461 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
463 static inline int task_curr_ret_stack(struct task_struct *tsk)
468 static inline void pause_graph_tracing(void) { }
469 static inline void unpause_graph_tracing(void) { }
472 #ifdef CONFIG_TRACING
473 #include <linux/sched.h>
475 /* flags for current->trace */
477 TSK_TRACE_FL_TRACE_BIT = 0,
478 TSK_TRACE_FL_GRAPH_BIT = 1,
481 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
482 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
485 static inline void set_tsk_trace_trace(struct task_struct *tsk)
487 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
490 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
492 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
495 static inline int test_tsk_trace_trace(struct task_struct *tsk)
497 return tsk->trace & TSK_TRACE_FL_TRACE;
500 static inline void set_tsk_trace_graph(struct task_struct *tsk)
502 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
505 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
507 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
510 static inline int test_tsk_trace_graph(struct task_struct *tsk)
512 return tsk->trace & TSK_TRACE_FL_GRAPH;
515 #endif /* CONFIG_TRACING */
518 #ifdef CONFIG_HW_BRANCH_TRACER
520 void trace_hw_branch(u64 from, u64 to);
521 void trace_hw_branch_oops(void);
523 #else /* CONFIG_HW_BRANCH_TRACER */
525 static inline void trace_hw_branch(u64 from, u64 to) {}
526 static inline void trace_hw_branch_oops(void) {}
528 #endif /* CONFIG_HW_BRANCH_TRACER */
530 #endif /* _LINUX_FTRACE_H */