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),
166 FTRACE_FL_FREE = (1 << 31),
169 #define FTRACE_FL_MASK (0x3UL << 30)
170 #define FTRACE_REF_MAX ((1 << 30) - 1)
174 unsigned long ip; /* address of mcount call-site */
175 struct dyn_ftrace *freelist;
179 struct dyn_ftrace *newlist;
181 struct dyn_arch_ftrace arch;
184 int ftrace_force_update(void);
185 void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
187 void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
189 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
190 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
192 int register_ftrace_command(struct ftrace_func_command *cmd);
193 int unregister_ftrace_command(struct ftrace_func_command *cmd);
196 FTRACE_UPDATE_CALLS = (1 << 0),
197 FTRACE_DISABLE_CALLS = (1 << 1),
198 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
199 FTRACE_START_FUNC_RET = (1 << 3),
200 FTRACE_STOP_FUNC_RET = (1 << 4),
204 FTRACE_UPDATE_IGNORE,
205 FTRACE_UPDATE_MAKE_CALL,
206 FTRACE_UPDATE_MAKE_NOP,
209 void arch_ftrace_update_code(int command);
211 struct ftrace_rec_iter;
213 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
214 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
215 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
217 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
218 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
219 void ftrace_run_stop_machine(int command);
220 int ftrace_location(unsigned long ip);
222 extern ftrace_func_t ftrace_trace_function;
224 /* defined in arch */
225 extern int ftrace_ip_converted(unsigned long ip);
226 extern int ftrace_dyn_arch_init(void *data);
227 extern int ftrace_update_ftrace_func(ftrace_func_t func);
228 extern void ftrace_caller(void);
229 extern void ftrace_call(void);
230 extern void mcount_call(void);
233 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
235 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
236 extern void ftrace_graph_caller(void);
237 extern int ftrace_enable_ftrace_graph_caller(void);
238 extern int ftrace_disable_ftrace_graph_caller(void);
240 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
241 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
245 * ftrace_make_nop - convert code into nop
246 * @mod: module structure if called by module load initialization
247 * @rec: the mcount call site record
248 * @addr: the address that the call site should be calling
250 * This is a very sensitive operation and great care needs
251 * to be taken by the arch. The operation should carefully
252 * read the location, check to see if what is read is indeed
253 * what we expect it to be, and then on success of the compare,
254 * it should write to the location.
256 * The code segment at @rec->ip should be a caller to @addr
260 * -EFAULT on error reading the location
261 * -EINVAL on a failed compare of the contents
262 * -EPERM on error writing to the location
263 * Any other value will be considered a failure.
265 extern int ftrace_make_nop(struct module *mod,
266 struct dyn_ftrace *rec, unsigned long addr);
269 * ftrace_make_call - convert a nop call site into a call to addr
270 * @rec: the mcount call site record
271 * @addr: the address that the call site should call
273 * This is a very sensitive operation and great care needs
274 * to be taken by the arch. The operation should carefully
275 * read the location, check to see if what is read is indeed
276 * what we expect it to be, and then on success of the compare,
277 * it should write to the location.
279 * The code segment at @rec->ip should be a nop
283 * -EFAULT on error reading the location
284 * -EINVAL on a failed compare of the contents
285 * -EPERM on error writing to the location
286 * Any other value will be considered a failure.
288 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
290 /* May be defined in arch */
291 extern int ftrace_arch_read_dyn_info(char *buf, int size);
293 extern int skip_trace(unsigned long ip);
295 extern void ftrace_disable_daemon(void);
296 extern void ftrace_enable_daemon(void);
298 static inline int skip_trace(unsigned long ip) { return 0; }
299 static inline int ftrace_force_update(void) { return 0; }
300 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset)
303 static inline void ftrace_disable_daemon(void) { }
304 static inline void ftrace_enable_daemon(void) { }
305 static inline void ftrace_release_mod(struct module *mod) {}
306 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
310 static inline int unregister_ftrace_command(char *cmd_name)
314 static inline int ftrace_text_reserved(void *start, void *end)
318 #endif /* CONFIG_DYNAMIC_FTRACE */
320 /* totally disable ftrace - can not re-enable after this */
321 void ftrace_kill(void);
323 static inline void tracer_disable(void)
325 #ifdef CONFIG_FUNCTION_TRACER
331 * Ftrace disable/restore without lock. Some synchronization mechanism
332 * must be used to prevent ftrace_enabled to be changed between
335 static inline int __ftrace_enabled_save(void)
337 #ifdef CONFIG_FUNCTION_TRACER
338 int saved_ftrace_enabled = ftrace_enabled;
340 return saved_ftrace_enabled;
346 static inline void __ftrace_enabled_restore(int enabled)
348 #ifdef CONFIG_FUNCTION_TRACER
349 ftrace_enabled = enabled;
353 #ifndef HAVE_ARCH_CALLER_ADDR
354 # ifdef CONFIG_FRAME_POINTER
355 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
356 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
357 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
358 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
359 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
360 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
361 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
363 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
364 # define CALLER_ADDR1 0UL
365 # define CALLER_ADDR2 0UL
366 # define CALLER_ADDR3 0UL
367 # define CALLER_ADDR4 0UL
368 # define CALLER_ADDR5 0UL
369 # define CALLER_ADDR6 0UL
371 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
373 #ifdef CONFIG_IRQSOFF_TRACER
374 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
375 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
377 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
378 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
381 #ifdef CONFIG_PREEMPT_TRACER
382 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
383 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
385 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { }
386 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { }
389 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
390 extern void ftrace_init(void);
392 static inline void ftrace_init(void) { }
396 * Structure that defines an entry function trace.
398 struct ftrace_graph_ent {
399 unsigned long func; /* Current function */
404 * Structure that defines a return function trace.
406 struct ftrace_graph_ret {
407 unsigned long func; /* Current function */
408 unsigned long long calltime;
409 unsigned long long rettime;
410 /* Number of functions that overran the depth limit for current task */
411 unsigned long overrun;
415 /* Type of the callback handlers for tracing function graph*/
416 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
417 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
419 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
422 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
425 * Stack of return addresses for functions
427 * Used in struct thread_info
429 struct ftrace_ret_stack {
432 unsigned long long calltime;
433 unsigned long long subtime;
438 * Primary handler of a function return.
439 * It relays on ftrace_return_to_handler.
440 * Defined in entry_32/64.S
442 extern void return_to_handler(void);
445 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
446 unsigned long frame_pointer);
449 * Sometimes we don't want to trace a function with the function
450 * graph tracer but we want them to keep traced by the usual function
451 * tracer if the function graph tracer is not configured.
453 #define __notrace_funcgraph notrace
456 * We want to which function is an entrypoint of a hardirq.
457 * That will help us to put a signal on output.
459 #define __irq_entry __attribute__((__section__(".irqentry.text")))
461 /* Limits of hardirq entrypoints */
462 extern char __irqentry_text_start[];
463 extern char __irqentry_text_end[];
465 #define FTRACE_RETFUNC_DEPTH 50
466 #define FTRACE_RETSTACK_ALLOC_SIZE 32
467 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
468 trace_func_graph_ent_t entryfunc);
470 extern void ftrace_graph_stop(void);
472 /* The current handlers in use */
473 extern trace_func_graph_ret_t ftrace_graph_return;
474 extern trace_func_graph_ent_t ftrace_graph_entry;
476 extern void unregister_ftrace_graph(void);
478 extern void ftrace_graph_init_task(struct task_struct *t);
479 extern void ftrace_graph_exit_task(struct task_struct *t);
480 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
482 static inline int task_curr_ret_stack(struct task_struct *t)
484 return t->curr_ret_stack;
487 static inline void pause_graph_tracing(void)
489 atomic_inc(¤t->tracing_graph_pause);
492 static inline void unpause_graph_tracing(void)
494 atomic_dec(¤t->tracing_graph_pause);
496 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
498 #define __notrace_funcgraph
500 #define INIT_FTRACE_GRAPH
502 static inline void ftrace_graph_init_task(struct task_struct *t) { }
503 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
504 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
506 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
507 trace_func_graph_ent_t entryfunc)
511 static inline void unregister_ftrace_graph(void) { }
513 static inline int task_curr_ret_stack(struct task_struct *tsk)
518 static inline void pause_graph_tracing(void) { }
519 static inline void unpause_graph_tracing(void) { }
520 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
522 #ifdef CONFIG_TRACING
524 /* flags for current->trace */
526 TSK_TRACE_FL_TRACE_BIT = 0,
527 TSK_TRACE_FL_GRAPH_BIT = 1,
530 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
531 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
534 static inline void set_tsk_trace_trace(struct task_struct *tsk)
536 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
539 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
541 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
544 static inline int test_tsk_trace_trace(struct task_struct *tsk)
546 return tsk->trace & TSK_TRACE_FL_TRACE;
549 static inline void set_tsk_trace_graph(struct task_struct *tsk)
551 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
554 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
556 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
559 static inline int test_tsk_trace_graph(struct task_struct *tsk)
561 return tsk->trace & TSK_TRACE_FL_GRAPH;
564 enum ftrace_dump_mode;
566 extern enum ftrace_dump_mode ftrace_dump_on_oops;
568 #ifdef CONFIG_PREEMPT
569 #define INIT_TRACE_RECURSION .trace_recursion = 0,
572 #endif /* CONFIG_TRACING */
574 #ifndef INIT_TRACE_RECURSION
575 #define INIT_TRACE_RECURSION
578 #ifdef CONFIG_FTRACE_SYSCALLS
580 unsigned long arch_syscall_addr(int nr);
582 #endif /* CONFIG_FTRACE_SYSCALLS */
584 #endif /* _LINUX_FTRACE_H */