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);
35 FTRACE_OPS_FL_ENABLED = 1 << 0,
36 FTRACE_OPS_FL_GLOBAL = 1 << 1,
41 struct ftrace_ops *next;
43 #ifdef CONFIG_DYNAMIC_FTRACE
44 struct ftrace_hash *notrace_hash;
45 struct ftrace_hash *filter_hash;
49 extern int function_trace_stop;
52 * Type of the current tracing.
54 enum ftrace_tracing_type_t {
55 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
56 FTRACE_TYPE_RETURN, /* Hook the return of the function */
59 /* Current tracing type, default is FTRACE_TYPE_ENTER */
60 extern enum ftrace_tracing_type_t ftrace_tracing_type;
63 * ftrace_stop - stop function tracer.
65 * A quick way to stop the function tracer. Note this an on off switch,
66 * it is not something that is recursive like preempt_disable.
67 * This does not disable the calling of mcount, it only stops the
68 * calling of functions from mcount.
70 static inline void ftrace_stop(void)
72 function_trace_stop = 1;
76 * ftrace_start - start the function tracer.
78 * This function is the inverse of ftrace_stop. This does not enable
79 * the function tracing if the function tracer is disabled. This only
80 * sets the function tracer flag to continue calling the functions
83 static inline void ftrace_start(void)
85 function_trace_stop = 0;
89 * The ftrace_ops must be a static and should also
90 * be read_mostly. These functions do modify read_mostly variables
91 * so use them sparely. Never free an ftrace_op or modify the
92 * next pointer after it has been registered. Even after unregistering
93 * it, the next pointer may still be used internally.
95 int register_ftrace_function(struct ftrace_ops *ops);
96 int unregister_ftrace_function(struct ftrace_ops *ops);
97 void clear_ftrace_function(void);
99 extern void ftrace_stub(unsigned long a0, unsigned long a1);
101 #else /* !CONFIG_FUNCTION_TRACER */
103 * (un)register_ftrace_function must be a macro since the ops parameter
104 * must not be evaluated.
106 #define register_ftrace_function(ops) ({ 0; })
107 #define unregister_ftrace_function(ops) ({ 0; })
108 static inline void clear_ftrace_function(void) { }
109 static inline void ftrace_kill(void) { }
110 static inline void ftrace_stop(void) { }
111 static inline void ftrace_start(void) { }
112 #endif /* CONFIG_FUNCTION_TRACER */
114 #ifdef CONFIG_STACK_TRACER
115 extern int stack_tracer_enabled;
117 stack_trace_sysctl(struct ctl_table *table, int write,
118 void __user *buffer, size_t *lenp,
122 struct ftrace_func_command {
123 struct list_head list;
125 int (*func)(char *func, char *cmd,
126 char *params, int enable);
129 #ifdef CONFIG_DYNAMIC_FTRACE
131 int ftrace_arch_code_modify_prepare(void);
132 int ftrace_arch_code_modify_post_process(void);
136 struct ftrace_probe_ops {
137 void (*func)(unsigned long ip,
138 unsigned long parent_ip,
140 int (*callback)(unsigned long ip, void **data);
141 void (*free)(void **data);
142 int (*print)(struct seq_file *m,
144 struct ftrace_probe_ops *ops,
149 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
152 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
155 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
156 extern void unregister_ftrace_function_probe_all(char *glob);
158 extern int ftrace_text_reserved(void *start, void *end);
161 FTRACE_FL_ENABLED = (1 << 30),
162 FTRACE_FL_FREE = (1 << 31),
165 #define FTRACE_FL_MASK (0x3UL << 30)
166 #define FTRACE_REF_MAX ((1 << 30) - 1)
170 unsigned long ip; /* address of mcount call-site */
171 struct dyn_ftrace *freelist;
175 struct dyn_ftrace *newlist;
177 struct dyn_arch_ftrace arch;
180 int ftrace_force_update(void);
181 void ftrace_set_filter(unsigned char *buf, int len, int reset);
183 int register_ftrace_command(struct ftrace_func_command *cmd);
184 int unregister_ftrace_command(struct ftrace_func_command *cmd);
186 /* defined in arch */
187 extern int ftrace_ip_converted(unsigned long ip);
188 extern int ftrace_dyn_arch_init(void *data);
189 extern int ftrace_update_ftrace_func(ftrace_func_t func);
190 extern void ftrace_caller(void);
191 extern void ftrace_call(void);
192 extern void mcount_call(void);
195 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
197 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
198 extern void ftrace_graph_caller(void);
199 extern int ftrace_enable_ftrace_graph_caller(void);
200 extern int ftrace_disable_ftrace_graph_caller(void);
202 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
203 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
207 * ftrace_make_nop - convert code into nop
208 * @mod: module structure if called by module load initialization
209 * @rec: the mcount call site record
210 * @addr: the address that the call site should be calling
212 * This is a very sensitive operation and great care needs
213 * to be taken by the arch. The operation should carefully
214 * read the location, check to see if what is read is indeed
215 * what we expect it to be, and then on success of the compare,
216 * it should write to the location.
218 * The code segment at @rec->ip should be a caller to @addr
222 * -EFAULT on error reading the location
223 * -EINVAL on a failed compare of the contents
224 * -EPERM on error writing to the location
225 * Any other value will be considered a failure.
227 extern int ftrace_make_nop(struct module *mod,
228 struct dyn_ftrace *rec, unsigned long addr);
231 * ftrace_make_call - convert a nop call site into a call to addr
232 * @rec: the mcount call site record
233 * @addr: the address that the call site should call
235 * This is a very sensitive operation and great care needs
236 * to be taken by the arch. The operation should carefully
237 * read the location, check to see if what is read is indeed
238 * what we expect it to be, and then on success of the compare,
239 * it should write to the location.
241 * The code segment at @rec->ip should be a nop
245 * -EFAULT on error reading the location
246 * -EINVAL on a failed compare of the contents
247 * -EPERM on error writing to the location
248 * Any other value will be considered a failure.
250 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
252 /* May be defined in arch */
253 extern int ftrace_arch_read_dyn_info(char *buf, int size);
255 extern int skip_trace(unsigned long ip);
257 extern void ftrace_disable_daemon(void);
258 extern void ftrace_enable_daemon(void);
260 static inline int skip_trace(unsigned long ip) { return 0; }
261 static inline int ftrace_force_update(void) { return 0; }
262 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset)
265 static inline void ftrace_disable_daemon(void) { }
266 static inline void ftrace_enable_daemon(void) { }
267 static inline void ftrace_release_mod(struct module *mod) {}
268 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
272 static inline int unregister_ftrace_command(char *cmd_name)
276 static inline int ftrace_text_reserved(void *start, void *end)
280 #endif /* CONFIG_DYNAMIC_FTRACE */
282 /* totally disable ftrace - can not re-enable after this */
283 void ftrace_kill(void);
285 static inline void tracer_disable(void)
287 #ifdef CONFIG_FUNCTION_TRACER
293 * Ftrace disable/restore without lock. Some synchronization mechanism
294 * must be used to prevent ftrace_enabled to be changed between
297 static inline int __ftrace_enabled_save(void)
299 #ifdef CONFIG_FUNCTION_TRACER
300 int saved_ftrace_enabled = ftrace_enabled;
302 return saved_ftrace_enabled;
308 static inline void __ftrace_enabled_restore(int enabled)
310 #ifdef CONFIG_FUNCTION_TRACER
311 ftrace_enabled = enabled;
315 #ifndef HAVE_ARCH_CALLER_ADDR
316 # ifdef CONFIG_FRAME_POINTER
317 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
318 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
319 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
320 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
321 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
322 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
323 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
325 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
326 # define CALLER_ADDR1 0UL
327 # define CALLER_ADDR2 0UL
328 # define CALLER_ADDR3 0UL
329 # define CALLER_ADDR4 0UL
330 # define CALLER_ADDR5 0UL
331 # define CALLER_ADDR6 0UL
333 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
335 #ifdef CONFIG_IRQSOFF_TRACER
336 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
337 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
339 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
340 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
343 #ifdef CONFIG_PREEMPT_TRACER
344 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
345 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
347 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { }
348 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { }
351 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
352 extern void ftrace_init(void);
354 static inline void ftrace_init(void) { }
358 * Structure that defines an entry function trace.
360 struct ftrace_graph_ent {
361 unsigned long func; /* Current function */
366 * Structure that defines a return function trace.
368 struct ftrace_graph_ret {
369 unsigned long func; /* Current function */
370 unsigned long long calltime;
371 unsigned long long rettime;
372 /* Number of functions that overran the depth limit for current task */
373 unsigned long overrun;
377 /* Type of the callback handlers for tracing function graph*/
378 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
379 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
381 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
384 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
387 * Stack of return addresses for functions
389 * Used in struct thread_info
391 struct ftrace_ret_stack {
394 unsigned long long calltime;
395 unsigned long long subtime;
400 * Primary handler of a function return.
401 * It relays on ftrace_return_to_handler.
402 * Defined in entry_32/64.S
404 extern void return_to_handler(void);
407 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
408 unsigned long frame_pointer);
411 * Sometimes we don't want to trace a function with the function
412 * graph tracer but we want them to keep traced by the usual function
413 * tracer if the function graph tracer is not configured.
415 #define __notrace_funcgraph notrace
418 * We want to which function is an entrypoint of a hardirq.
419 * That will help us to put a signal on output.
421 #define __irq_entry __attribute__((__section__(".irqentry.text")))
423 /* Limits of hardirq entrypoints */
424 extern char __irqentry_text_start[];
425 extern char __irqentry_text_end[];
427 #define FTRACE_RETFUNC_DEPTH 50
428 #define FTRACE_RETSTACK_ALLOC_SIZE 32
429 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
430 trace_func_graph_ent_t entryfunc);
432 extern void ftrace_graph_stop(void);
434 /* The current handlers in use */
435 extern trace_func_graph_ret_t ftrace_graph_return;
436 extern trace_func_graph_ent_t ftrace_graph_entry;
438 extern void unregister_ftrace_graph(void);
440 extern void ftrace_graph_init_task(struct task_struct *t);
441 extern void ftrace_graph_exit_task(struct task_struct *t);
442 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
444 static inline int task_curr_ret_stack(struct task_struct *t)
446 return t->curr_ret_stack;
449 static inline void pause_graph_tracing(void)
451 atomic_inc(¤t->tracing_graph_pause);
454 static inline void unpause_graph_tracing(void)
456 atomic_dec(¤t->tracing_graph_pause);
458 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
460 #define __notrace_funcgraph
462 #define INIT_FTRACE_GRAPH
464 static inline void ftrace_graph_init_task(struct task_struct *t) { }
465 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
466 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
468 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
469 trace_func_graph_ent_t entryfunc)
473 static inline void unregister_ftrace_graph(void) { }
475 static inline int task_curr_ret_stack(struct task_struct *tsk)
480 static inline void pause_graph_tracing(void) { }
481 static inline void unpause_graph_tracing(void) { }
482 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
484 #ifdef CONFIG_TRACING
486 /* flags for current->trace */
488 TSK_TRACE_FL_TRACE_BIT = 0,
489 TSK_TRACE_FL_GRAPH_BIT = 1,
492 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
493 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
496 static inline void set_tsk_trace_trace(struct task_struct *tsk)
498 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
501 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
503 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
506 static inline int test_tsk_trace_trace(struct task_struct *tsk)
508 return tsk->trace & TSK_TRACE_FL_TRACE;
511 static inline void set_tsk_trace_graph(struct task_struct *tsk)
513 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
516 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
518 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
521 static inline int test_tsk_trace_graph(struct task_struct *tsk)
523 return tsk->trace & TSK_TRACE_FL_GRAPH;
526 enum ftrace_dump_mode;
528 extern enum ftrace_dump_mode ftrace_dump_on_oops;
530 #ifdef CONFIG_PREEMPT
531 #define INIT_TRACE_RECURSION .trace_recursion = 0,
534 #endif /* CONFIG_TRACING */
536 #ifndef INIT_TRACE_RECURSION
537 #define INIT_TRACE_RECURSION
540 #ifdef CONFIG_FTRACE_SYSCALLS
542 unsigned long arch_syscall_addr(int nr);
544 #endif /* CONFIG_FTRACE_SYSCALLS */
546 #endif /* _LINUX_FTRACE_H */