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/module.h>
14 #include <linux/ktime.h>
15 #include <linux/sched.h>
16 #include <linux/types.h>
17 #include <linux/init.h>
20 #include <asm/ftrace.h>
22 #ifdef CONFIG_FUNCTION_TRACER
24 extern int ftrace_enabled;
26 ftrace_enable_sysctl(struct ctl_table *table, int write,
27 void __user *buffer, size_t *lenp,
30 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
34 struct ftrace_ops *next;
37 extern int function_trace_stop;
40 * Type of the current tracing.
42 enum ftrace_tracing_type_t {
43 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
44 FTRACE_TYPE_RETURN, /* Hook the return of the function */
47 /* Current tracing type, default is FTRACE_TYPE_ENTER */
48 extern enum ftrace_tracing_type_t ftrace_tracing_type;
51 * ftrace_stop - stop function tracer.
53 * A quick way to stop the function tracer. Note this an on off switch,
54 * it is not something that is recursive like preempt_disable.
55 * This does not disable the calling of mcount, it only stops the
56 * calling of functions from mcount.
58 static inline void ftrace_stop(void)
60 function_trace_stop = 1;
64 * ftrace_start - start the function tracer.
66 * This function is the inverse of ftrace_stop. This does not enable
67 * the function tracing if the function tracer is disabled. This only
68 * sets the function tracer flag to continue calling the functions
71 static inline void ftrace_start(void)
73 function_trace_stop = 0;
77 * The ftrace_ops must be a static and should also
78 * be read_mostly. These functions do modify read_mostly variables
79 * so use them sparely. Never free an ftrace_op or modify the
80 * next pointer after it has been registered. Even after unregistering
81 * it, the next pointer may still be used internally.
83 int register_ftrace_function(struct ftrace_ops *ops);
84 int unregister_ftrace_function(struct ftrace_ops *ops);
85 void clear_ftrace_function(void);
87 extern void ftrace_stub(unsigned long a0, unsigned long a1);
89 #else /* !CONFIG_FUNCTION_TRACER */
91 * (un)register_ftrace_function must be a macro since the ops parameter
92 * must not be evaluated.
94 #define register_ftrace_function(ops) ({ 0; })
95 #define unregister_ftrace_function(ops) ({ 0; })
96 static inline void clear_ftrace_function(void) { }
97 static inline void ftrace_kill(void) { }
98 static inline void ftrace_stop(void) { }
99 static inline void ftrace_start(void) { }
100 #endif /* CONFIG_FUNCTION_TRACER */
102 #ifdef CONFIG_STACK_TRACER
103 extern int stack_tracer_enabled;
105 stack_trace_sysctl(struct ctl_table *table, int write,
106 void __user *buffer, size_t *lenp,
110 struct ftrace_func_command {
111 struct list_head list;
113 int (*func)(char *func, char *cmd,
114 char *params, int enable);
117 #ifdef CONFIG_DYNAMIC_FTRACE
119 int ftrace_arch_code_modify_prepare(void);
120 int ftrace_arch_code_modify_post_process(void);
124 struct ftrace_probe_ops {
125 void (*func)(unsigned long ip,
126 unsigned long parent_ip,
128 int (*callback)(unsigned long ip, void **data);
129 void (*free)(void **data);
130 int (*print)(struct seq_file *m,
132 struct ftrace_probe_ops *ops,
137 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
140 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
143 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
144 extern void unregister_ftrace_function_probe_all(char *glob);
146 extern int ftrace_text_reserved(void *start, void *end);
149 FTRACE_FL_FREE = (1 << 0),
150 FTRACE_FL_ENABLED = (1 << 1),
155 unsigned long ip; /* address of mcount call-site */
156 struct dyn_ftrace *freelist;
160 struct dyn_ftrace *newlist;
162 struct dyn_arch_ftrace arch;
165 int ftrace_force_update(void);
166 void ftrace_set_filter(unsigned char *buf, int len, int reset);
168 int register_ftrace_command(struct ftrace_func_command *cmd);
169 int unregister_ftrace_command(struct ftrace_func_command *cmd);
171 /* defined in arch */
172 extern int ftrace_ip_converted(unsigned long ip);
173 extern int ftrace_dyn_arch_init(void *data);
174 extern int ftrace_update_ftrace_func(ftrace_func_t func);
175 extern void ftrace_caller(void);
176 extern void ftrace_call(void);
177 extern void mcount_call(void);
180 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
182 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
183 extern void ftrace_graph_caller(void);
184 extern int ftrace_enable_ftrace_graph_caller(void);
185 extern int ftrace_disable_ftrace_graph_caller(void);
187 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
188 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
192 * ftrace_make_nop - convert code into nop
193 * @mod: module structure if called by module load initialization
194 * @rec: the mcount call site record
195 * @addr: the address that the call site should be calling
197 * This is a very sensitive operation and great care needs
198 * to be taken by the arch. The operation should carefully
199 * read the location, check to see if what is read is indeed
200 * what we expect it to be, and then on success of the compare,
201 * it should write to the location.
203 * The code segment at @rec->ip should be a caller to @addr
207 * -EFAULT on error reading the location
208 * -EINVAL on a failed compare of the contents
209 * -EPERM on error writing to the location
210 * Any other value will be considered a failure.
212 extern int ftrace_make_nop(struct module *mod,
213 struct dyn_ftrace *rec, unsigned long addr);
216 * ftrace_make_call - convert a nop call site into a call to addr
217 * @rec: the mcount call site record
218 * @addr: the address that the call site should call
220 * This is a very sensitive operation and great care needs
221 * to be taken by the arch. The operation should carefully
222 * read the location, check to see if what is read is indeed
223 * what we expect it to be, and then on success of the compare,
224 * it should write to the location.
226 * The code segment at @rec->ip should be a nop
230 * -EFAULT on error reading the location
231 * -EINVAL on a failed compare of the contents
232 * -EPERM on error writing to the location
233 * Any other value will be considered a failure.
235 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
237 /* May be defined in arch */
238 extern int ftrace_arch_read_dyn_info(char *buf, int size);
240 extern int skip_trace(unsigned long ip);
242 extern void ftrace_disable_daemon(void);
243 extern void ftrace_enable_daemon(void);
245 static inline int skip_trace(unsigned long ip) { return 0; }
246 static inline int ftrace_force_update(void) { return 0; }
247 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset)
250 static inline void ftrace_disable_daemon(void) { }
251 static inline void ftrace_enable_daemon(void) { }
252 static inline void ftrace_release_mod(struct module *mod) {}
253 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
257 static inline int unregister_ftrace_command(char *cmd_name)
261 static inline int ftrace_text_reserved(void *start, void *end)
265 #endif /* CONFIG_DYNAMIC_FTRACE */
267 /* totally disable ftrace - can not re-enable after this */
268 void ftrace_kill(void);
270 static inline void tracer_disable(void)
272 #ifdef CONFIG_FUNCTION_TRACER
278 * Ftrace disable/restore without lock. Some synchronization mechanism
279 * must be used to prevent ftrace_enabled to be changed between
282 static inline int __ftrace_enabled_save(void)
284 #ifdef CONFIG_FUNCTION_TRACER
285 int saved_ftrace_enabled = ftrace_enabled;
287 return saved_ftrace_enabled;
293 static inline void __ftrace_enabled_restore(int enabled)
295 #ifdef CONFIG_FUNCTION_TRACER
296 ftrace_enabled = enabled;
300 #ifndef HAVE_ARCH_CALLER_ADDR
301 # ifdef CONFIG_FRAME_POINTER
302 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
303 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
304 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
305 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
306 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
307 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
308 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
310 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
311 # define CALLER_ADDR1 0UL
312 # define CALLER_ADDR2 0UL
313 # define CALLER_ADDR3 0UL
314 # define CALLER_ADDR4 0UL
315 # define CALLER_ADDR5 0UL
316 # define CALLER_ADDR6 0UL
318 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
320 #ifdef CONFIG_IRQSOFF_TRACER
321 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
322 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
324 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
325 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
328 #ifdef CONFIG_PREEMPT_TRACER
329 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
330 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
332 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { }
333 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { }
336 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
337 extern void ftrace_init(void);
339 static inline void ftrace_init(void) { }
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 /* Type of the callback handlers for tracing function graph*/
363 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
364 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
366 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
369 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
372 * Stack of return addresses for functions
374 * Used in struct thread_info
376 struct ftrace_ret_stack {
379 unsigned long long calltime;
380 unsigned long long subtime;
385 * Primary handler of a function return.
386 * It relays on ftrace_return_to_handler.
387 * Defined in entry_32/64.S
389 extern void return_to_handler(void);
392 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
393 unsigned long frame_pointer);
396 * Sometimes we don't want to trace a function with the function
397 * graph tracer but we want them to keep traced by the usual function
398 * tracer if the function graph tracer is not configured.
400 #define __notrace_funcgraph notrace
403 * We want to which function is an entrypoint of a hardirq.
404 * That will help us to put a signal on output.
406 #define __irq_entry __attribute__((__section__(".irqentry.text")))
408 /* Limits of hardirq entrypoints */
409 extern char __irqentry_text_start[];
410 extern char __irqentry_text_end[];
412 #define FTRACE_RETFUNC_DEPTH 50
413 #define FTRACE_RETSTACK_ALLOC_SIZE 32
414 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
415 trace_func_graph_ent_t entryfunc);
417 extern void ftrace_graph_stop(void);
419 /* The current handlers in use */
420 extern trace_func_graph_ret_t ftrace_graph_return;
421 extern trace_func_graph_ent_t ftrace_graph_entry;
423 extern void unregister_ftrace_graph(void);
425 extern void ftrace_graph_init_task(struct task_struct *t);
426 extern void ftrace_graph_exit_task(struct task_struct *t);
427 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
429 static inline int task_curr_ret_stack(struct task_struct *t)
431 return t->curr_ret_stack;
434 static inline void pause_graph_tracing(void)
436 atomic_inc(¤t->tracing_graph_pause);
439 static inline void unpause_graph_tracing(void)
441 atomic_dec(¤t->tracing_graph_pause);
443 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
445 #define __notrace_funcgraph
447 #define INIT_FTRACE_GRAPH
449 static inline void ftrace_graph_init_task(struct task_struct *t) { }
450 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
451 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
453 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
454 trace_func_graph_ent_t entryfunc)
458 static inline void unregister_ftrace_graph(void) { }
460 static inline int task_curr_ret_stack(struct task_struct *tsk)
465 static inline void pause_graph_tracing(void) { }
466 static inline void unpause_graph_tracing(void) { }
467 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
469 #ifdef CONFIG_TRACING
471 /* flags for current->trace */
473 TSK_TRACE_FL_TRACE_BIT = 0,
474 TSK_TRACE_FL_GRAPH_BIT = 1,
477 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
478 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
481 static inline void set_tsk_trace_trace(struct task_struct *tsk)
483 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
486 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
488 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
491 static inline int test_tsk_trace_trace(struct task_struct *tsk)
493 return tsk->trace & TSK_TRACE_FL_TRACE;
496 static inline void set_tsk_trace_graph(struct task_struct *tsk)
498 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
501 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
503 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
506 static inline int test_tsk_trace_graph(struct task_struct *tsk)
508 return tsk->trace & TSK_TRACE_FL_GRAPH;
511 enum ftrace_dump_mode;
513 extern enum ftrace_dump_mode ftrace_dump_on_oops;
515 #ifdef CONFIG_PREEMPT
516 #define INIT_TRACE_RECURSION .trace_recursion = 0,
519 #endif /* CONFIG_TRACING */
521 #ifndef INIT_TRACE_RECURSION
522 #define INIT_TRACE_RECURSION
525 #ifdef CONFIG_FTRACE_SYSCALLS
527 unsigned long arch_syscall_addr(int nr);
529 #endif /* CONFIG_FTRACE_SYSCALLS */
531 #endif /* _LINUX_FTRACE_H */