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,
205 void arch_ftrace_update_code(int command);
207 struct ftrace_rec_iter;
209 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
210 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
211 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
213 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
214 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
215 void ftrace_run_stop_machine(int command);
216 int ftrace_location(unsigned long ip);
218 extern ftrace_func_t ftrace_trace_function;
220 /* defined in arch */
221 extern int ftrace_ip_converted(unsigned long ip);
222 extern int ftrace_dyn_arch_init(void *data);
223 extern int ftrace_update_ftrace_func(ftrace_func_t func);
224 extern void ftrace_caller(void);
225 extern void ftrace_call(void);
226 extern void mcount_call(void);
229 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
231 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
232 extern void ftrace_graph_caller(void);
233 extern int ftrace_enable_ftrace_graph_caller(void);
234 extern int ftrace_disable_ftrace_graph_caller(void);
236 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
237 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
241 * ftrace_make_nop - convert code into nop
242 * @mod: module structure if called by module load initialization
243 * @rec: the mcount call site record
244 * @addr: the address that the call site should be calling
246 * This is a very sensitive operation and great care needs
247 * to be taken by the arch. The operation should carefully
248 * read the location, check to see if what is read is indeed
249 * what we expect it to be, and then on success of the compare,
250 * it should write to the location.
252 * The code segment at @rec->ip should be a caller to @addr
256 * -EFAULT on error reading the location
257 * -EINVAL on a failed compare of the contents
258 * -EPERM on error writing to the location
259 * Any other value will be considered a failure.
261 extern int ftrace_make_nop(struct module *mod,
262 struct dyn_ftrace *rec, unsigned long addr);
265 * ftrace_make_call - convert a nop call site into a call to addr
266 * @rec: the mcount call site record
267 * @addr: the address that the call site should call
269 * This is a very sensitive operation and great care needs
270 * to be taken by the arch. The operation should carefully
271 * read the location, check to see if what is read is indeed
272 * what we expect it to be, and then on success of the compare,
273 * it should write to the location.
275 * The code segment at @rec->ip should be a nop
279 * -EFAULT on error reading the location
280 * -EINVAL on a failed compare of the contents
281 * -EPERM on error writing to the location
282 * Any other value will be considered a failure.
284 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
286 /* May be defined in arch */
287 extern int ftrace_arch_read_dyn_info(char *buf, int size);
289 extern int skip_trace(unsigned long ip);
291 extern void ftrace_disable_daemon(void);
292 extern void ftrace_enable_daemon(void);
294 static inline int skip_trace(unsigned long ip) { return 0; }
295 static inline int ftrace_force_update(void) { return 0; }
296 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset)
299 static inline void ftrace_disable_daemon(void) { }
300 static inline void ftrace_enable_daemon(void) { }
301 static inline void ftrace_release_mod(struct module *mod) {}
302 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
306 static inline int unregister_ftrace_command(char *cmd_name)
310 static inline int ftrace_text_reserved(void *start, void *end)
314 #endif /* CONFIG_DYNAMIC_FTRACE */
316 /* totally disable ftrace - can not re-enable after this */
317 void ftrace_kill(void);
319 static inline void tracer_disable(void)
321 #ifdef CONFIG_FUNCTION_TRACER
327 * Ftrace disable/restore without lock. Some synchronization mechanism
328 * must be used to prevent ftrace_enabled to be changed between
331 static inline int __ftrace_enabled_save(void)
333 #ifdef CONFIG_FUNCTION_TRACER
334 int saved_ftrace_enabled = ftrace_enabled;
336 return saved_ftrace_enabled;
342 static inline void __ftrace_enabled_restore(int enabled)
344 #ifdef CONFIG_FUNCTION_TRACER
345 ftrace_enabled = enabled;
349 #ifndef HAVE_ARCH_CALLER_ADDR
350 # ifdef CONFIG_FRAME_POINTER
351 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
352 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
353 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
354 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
355 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
356 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
357 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
359 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
360 # define CALLER_ADDR1 0UL
361 # define CALLER_ADDR2 0UL
362 # define CALLER_ADDR3 0UL
363 # define CALLER_ADDR4 0UL
364 # define CALLER_ADDR5 0UL
365 # define CALLER_ADDR6 0UL
367 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
369 #ifdef CONFIG_IRQSOFF_TRACER
370 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
371 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
373 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
374 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
377 #ifdef CONFIG_PREEMPT_TRACER
378 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
379 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
381 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { }
382 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { }
385 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
386 extern void ftrace_init(void);
388 static inline void ftrace_init(void) { }
392 * Structure that defines an entry function trace.
394 struct ftrace_graph_ent {
395 unsigned long func; /* Current function */
400 * Structure that defines a return function trace.
402 struct ftrace_graph_ret {
403 unsigned long func; /* Current function */
404 unsigned long long calltime;
405 unsigned long long rettime;
406 /* Number of functions that overran the depth limit for current task */
407 unsigned long overrun;
411 /* Type of the callback handlers for tracing function graph*/
412 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
413 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
415 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
418 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
421 * Stack of return addresses for functions
423 * Used in struct thread_info
425 struct ftrace_ret_stack {
428 unsigned long long calltime;
429 unsigned long long subtime;
434 * Primary handler of a function return.
435 * It relays on ftrace_return_to_handler.
436 * Defined in entry_32/64.S
438 extern void return_to_handler(void);
441 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
442 unsigned long frame_pointer);
445 * Sometimes we don't want to trace a function with the function
446 * graph tracer but we want them to keep traced by the usual function
447 * tracer if the function graph tracer is not configured.
449 #define __notrace_funcgraph notrace
452 * We want to which function is an entrypoint of a hardirq.
453 * That will help us to put a signal on output.
455 #define __irq_entry __attribute__((__section__(".irqentry.text")))
457 /* Limits of hardirq entrypoints */
458 extern char __irqentry_text_start[];
459 extern char __irqentry_text_end[];
461 #define FTRACE_RETFUNC_DEPTH 50
462 #define FTRACE_RETSTACK_ALLOC_SIZE 32
463 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
464 trace_func_graph_ent_t entryfunc);
466 extern void ftrace_graph_stop(void);
468 /* The current handlers in use */
469 extern trace_func_graph_ret_t ftrace_graph_return;
470 extern trace_func_graph_ent_t ftrace_graph_entry;
472 extern void unregister_ftrace_graph(void);
474 extern void ftrace_graph_init_task(struct task_struct *t);
475 extern void ftrace_graph_exit_task(struct task_struct *t);
476 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
478 static inline int task_curr_ret_stack(struct task_struct *t)
480 return t->curr_ret_stack;
483 static inline void pause_graph_tracing(void)
485 atomic_inc(¤t->tracing_graph_pause);
488 static inline void unpause_graph_tracing(void)
490 atomic_dec(¤t->tracing_graph_pause);
492 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
494 #define __notrace_funcgraph
496 #define INIT_FTRACE_GRAPH
498 static inline void ftrace_graph_init_task(struct task_struct *t) { }
499 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
500 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
502 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
503 trace_func_graph_ent_t entryfunc)
507 static inline void unregister_ftrace_graph(void) { }
509 static inline int task_curr_ret_stack(struct task_struct *tsk)
514 static inline void pause_graph_tracing(void) { }
515 static inline void unpause_graph_tracing(void) { }
516 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
518 #ifdef CONFIG_TRACING
520 /* flags for current->trace */
522 TSK_TRACE_FL_TRACE_BIT = 0,
523 TSK_TRACE_FL_GRAPH_BIT = 1,
526 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
527 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
530 static inline void set_tsk_trace_trace(struct task_struct *tsk)
532 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
535 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
537 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
540 static inline int test_tsk_trace_trace(struct task_struct *tsk)
542 return tsk->trace & TSK_TRACE_FL_TRACE;
545 static inline void set_tsk_trace_graph(struct task_struct *tsk)
547 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
550 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
552 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
555 static inline int test_tsk_trace_graph(struct task_struct *tsk)
557 return tsk->trace & TSK_TRACE_FL_GRAPH;
560 enum ftrace_dump_mode;
562 extern enum ftrace_dump_mode ftrace_dump_on_oops;
564 #ifdef CONFIG_PREEMPT
565 #define INIT_TRACE_RECURSION .trace_recursion = 0,
568 #endif /* CONFIG_TRACING */
570 #ifndef INIT_TRACE_RECURSION
571 #define INIT_TRACE_RECURSION
574 #ifdef CONFIG_FTRACE_SYSCALLS
576 unsigned long arch_syscall_addr(int nr);
578 #endif /* CONFIG_FTRACE_SYSCALLS */
580 #endif /* _LINUX_FTRACE_H */