1 #ifndef _LINUX_FTRACE_H
2 #define _LINUX_FTRACE_H
4 #include <linux/trace_clock.h>
5 #include <linux/kallsyms.h>
6 #include <linux/linkage.h>
7 #include <linux/bitops.h>
8 #include <linux/module.h>
9 #include <linux/ktime.h>
10 #include <linux/sched.h>
11 #include <linux/types.h>
12 #include <linux/init.h>
15 #include <asm/ftrace.h>
17 #ifdef CONFIG_FUNCTION_TRACER
19 extern int ftrace_enabled;
21 ftrace_enable_sysctl(struct ctl_table *table, int write,
22 struct file *filp, void __user *buffer, size_t *lenp,
25 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
29 struct ftrace_ops *next;
32 extern int function_trace_stop;
35 * Type of the current tracing.
37 enum ftrace_tracing_type_t {
38 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
39 FTRACE_TYPE_RETURN, /* Hook the return of the function */
42 /* Current tracing type, default is FTRACE_TYPE_ENTER */
43 extern enum ftrace_tracing_type_t ftrace_tracing_type;
46 * ftrace_stop - stop function tracer.
48 * A quick way to stop the function tracer. Note this an on off switch,
49 * it is not something that is recursive like preempt_disable.
50 * This does not disable the calling of mcount, it only stops the
51 * calling of functions from mcount.
53 static inline void ftrace_stop(void)
55 function_trace_stop = 1;
59 * ftrace_start - start the function tracer.
61 * This function is the inverse of ftrace_stop. This does not enable
62 * the function tracing if the function tracer is disabled. This only
63 * sets the function tracer flag to continue calling the functions
66 static inline void ftrace_start(void)
68 function_trace_stop = 0;
72 * The ftrace_ops must be a static and should also
73 * be read_mostly. These functions do modify read_mostly variables
74 * so use them sparely. Never free an ftrace_op or modify the
75 * next pointer after it has been registered. Even after unregistering
76 * it, the next pointer may still be used internally.
78 int register_ftrace_function(struct ftrace_ops *ops);
79 int unregister_ftrace_function(struct ftrace_ops *ops);
80 void clear_ftrace_function(void);
82 extern void ftrace_stub(unsigned long a0, unsigned long a1);
84 #else /* !CONFIG_FUNCTION_TRACER */
85 # define register_ftrace_function(ops) do { } while (0)
86 # define unregister_ftrace_function(ops) do { } while (0)
87 # define clear_ftrace_function(ops) do { } while (0)
88 static inline void ftrace_kill(void) { }
89 static inline void ftrace_stop(void) { }
90 static inline void ftrace_start(void) { }
91 #endif /* CONFIG_FUNCTION_TRACER */
93 #ifdef CONFIG_STACK_TRACER
94 extern int stack_tracer_enabled;
96 stack_trace_sysctl(struct ctl_table *table, int write,
97 struct file *file, void __user *buffer, size_t *lenp,
101 struct ftrace_func_command {
102 struct list_head list;
104 int (*func)(char *func, char *cmd,
105 char *params, int enable);
108 #ifdef CONFIG_DYNAMIC_FTRACE
110 int ftrace_arch_code_modify_prepare(void);
111 int ftrace_arch_code_modify_post_process(void);
115 struct ftrace_probe_ops {
116 void (*func)(unsigned long ip,
117 unsigned long parent_ip,
119 int (*callback)(unsigned long ip, void **data);
120 void (*free)(void **data);
121 int (*print)(struct seq_file *m,
123 struct ftrace_probe_ops *ops,
128 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
131 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
134 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
135 extern void unregister_ftrace_function_probe_all(char *glob);
138 FTRACE_FL_FREE = (1 << 0),
139 FTRACE_FL_FAILED = (1 << 1),
140 FTRACE_FL_FILTER = (1 << 2),
141 FTRACE_FL_ENABLED = (1 << 3),
142 FTRACE_FL_NOTRACE = (1 << 4),
143 FTRACE_FL_CONVERTED = (1 << 5),
144 FTRACE_FL_FROZEN = (1 << 6),
148 struct list_head list;
149 unsigned long ip; /* address of mcount call-site */
151 struct dyn_arch_ftrace arch;
154 int ftrace_force_update(void);
155 void ftrace_set_filter(unsigned char *buf, int len, int reset);
157 int register_ftrace_command(struct ftrace_func_command *cmd);
158 int unregister_ftrace_command(struct ftrace_func_command *cmd);
160 /* defined in arch */
161 extern int ftrace_ip_converted(unsigned long ip);
162 extern int ftrace_dyn_arch_init(void *data);
163 extern int ftrace_update_ftrace_func(ftrace_func_t func);
164 extern void ftrace_caller(void);
165 extern void ftrace_call(void);
166 extern void mcount_call(void);
169 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
171 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
172 extern void ftrace_graph_caller(void);
173 extern int ftrace_enable_ftrace_graph_caller(void);
174 extern int ftrace_disable_ftrace_graph_caller(void);
176 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
177 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
181 * ftrace_make_nop - convert code into nop
182 * @mod: module structure if called by module load initialization
183 * @rec: the mcount call site record
184 * @addr: the address that the call site should be calling
186 * This is a very sensitive operation and great care needs
187 * to be taken by the arch. The operation should carefully
188 * read the location, check to see if what is read is indeed
189 * what we expect it to be, and then on success of the compare,
190 * it should write to the location.
192 * The code segment at @rec->ip should be a caller to @addr
196 * -EFAULT on error reading the location
197 * -EINVAL on a failed compare of the contents
198 * -EPERM on error writing to the location
199 * Any other value will be considered a failure.
201 extern int ftrace_make_nop(struct module *mod,
202 struct dyn_ftrace *rec, unsigned long addr);
205 * ftrace_make_call - convert a nop call site into a call to addr
206 * @rec: the mcount call site record
207 * @addr: the address that the call site should call
209 * This is a very sensitive operation and great care needs
210 * to be taken by the arch. The operation should carefully
211 * read the location, check to see if what is read is indeed
212 * what we expect it to be, and then on success of the compare,
213 * it should write to the location.
215 * The code segment at @rec->ip should be a nop
219 * -EFAULT on error reading the location
220 * -EINVAL on a failed compare of the contents
221 * -EPERM on error writing to the location
222 * Any other value will be considered a failure.
224 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
227 /* May be defined in arch */
228 extern int ftrace_arch_read_dyn_info(char *buf, int size);
230 extern int skip_trace(unsigned long ip);
232 extern void ftrace_release(void *start, unsigned long size);
234 extern void ftrace_disable_daemon(void);
235 extern void ftrace_enable_daemon(void);
237 # define skip_trace(ip) ({ 0; })
238 # define ftrace_force_update() ({ 0; })
239 # define ftrace_set_filter(buf, len, reset) do { } while (0)
240 # define ftrace_disable_daemon() do { } while (0)
241 # define ftrace_enable_daemon() do { } while (0)
242 static inline void ftrace_release(void *start, unsigned long size) { }
243 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
247 static inline int unregister_ftrace_command(char *cmd_name)
251 #endif /* CONFIG_DYNAMIC_FTRACE */
253 /* totally disable ftrace - can not re-enable after this */
254 void ftrace_kill(void);
256 static inline void tracer_disable(void)
258 #ifdef CONFIG_FUNCTION_TRACER
264 * Ftrace disable/restore without lock. Some synchronization mechanism
265 * must be used to prevent ftrace_enabled to be changed between
268 static inline int __ftrace_enabled_save(void)
270 #ifdef CONFIG_FUNCTION_TRACER
271 int saved_ftrace_enabled = ftrace_enabled;
273 return saved_ftrace_enabled;
279 static inline void __ftrace_enabled_restore(int enabled)
281 #ifdef CONFIG_FUNCTION_TRACER
282 ftrace_enabled = enabled;
286 #ifndef HAVE_ARCH_CALLER_ADDR
287 # ifdef CONFIG_FRAME_POINTER
288 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
289 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
290 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
291 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
292 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
293 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
294 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
296 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
297 # define CALLER_ADDR1 0UL
298 # define CALLER_ADDR2 0UL
299 # define CALLER_ADDR3 0UL
300 # define CALLER_ADDR4 0UL
301 # define CALLER_ADDR5 0UL
302 # define CALLER_ADDR6 0UL
304 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
306 #ifdef CONFIG_IRQSOFF_TRACER
307 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
308 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
310 # define time_hardirqs_on(a0, a1) do { } while (0)
311 # define time_hardirqs_off(a0, a1) do { } while (0)
314 #ifdef CONFIG_PREEMPT_TRACER
315 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
316 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
318 # define trace_preempt_on(a0, a1) do { } while (0)
319 # define trace_preempt_off(a0, a1) do { } while (0)
322 #ifdef CONFIG_TRACING
323 extern int ftrace_dump_on_oops;
325 extern void tracing_start(void);
326 extern void tracing_stop(void);
327 extern void ftrace_off_permanent(void);
330 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
333 * ftrace_printk - printf formatting in the ftrace buffer
334 * @fmt: the printf format for printing
336 * Note: __ftrace_printk is an internal function for ftrace_printk and
337 * the @ip is passed in via the ftrace_printk macro.
339 * This function allows a kernel developer to debug fast path sections
340 * that printk is not appropriate for. By scattering in various
341 * printk like tracing in the code, a developer can quickly see
342 * where problems are occurring.
344 * This is intended as a debugging tool for the developer only.
345 * Please refrain from leaving ftrace_printks scattered around in
348 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
350 __ftrace_printk(unsigned long ip, const char *fmt, ...)
351 __attribute__ ((format (printf, 2, 3)));
352 # define ftrace_vprintk(fmt, ap) __ftrace_printk(_THIS_IP_, fmt, ap)
354 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
355 extern void ftrace_dump(void);
358 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
360 ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
362 static inline void tracing_start(void) { }
363 static inline void tracing_stop(void) { }
364 static inline void ftrace_off_permanent(void) { }
366 ftrace_printk(const char *fmt, ...)
371 ftrace_vprintk(const char *fmt, va_list ap)
375 static inline void ftrace_dump(void) { }
378 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
379 extern void ftrace_init(void);
380 extern void ftrace_init_module(struct module *mod,
381 unsigned long *start, unsigned long *end);
383 static inline void ftrace_init(void) { }
385 ftrace_init_module(struct module *mod,
386 unsigned long *start, unsigned long *end) { }
390 * Structure that defines an entry function trace.
392 struct ftrace_graph_ent {
393 unsigned long func; /* Current function */
398 * Structure that defines a return function trace.
400 struct ftrace_graph_ret {
401 unsigned long func; /* Current function */
402 unsigned long long calltime;
403 unsigned long long rettime;
404 /* Number of functions that overran the depth limit for current task */
405 unsigned long overrun;
409 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
412 * Stack of return addresses for functions
414 * Used in struct thread_info
416 struct ftrace_ret_stack {
419 unsigned long long calltime;
423 * Primary handler of a function return.
424 * It relays on ftrace_return_to_handler.
425 * Defined in entry_32/64.S
427 extern void return_to_handler(void);
430 ftrace_push_return_trace(unsigned long ret, unsigned long long time,
431 unsigned long func, int *depth);
433 ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret);
436 * Sometimes we don't want to trace a function with the function
437 * graph tracer but we want them to keep traced by the usual function
438 * tracer if the function graph tracer is not configured.
440 #define __notrace_funcgraph notrace
443 * We want to which function is an entrypoint of a hardirq.
444 * That will help us to put a signal on output.
446 #define __irq_entry __attribute__((__section__(".irqentry.text")))
448 /* Limits of hardirq entrypoints */
449 extern char __irqentry_text_start[];
450 extern char __irqentry_text_end[];
452 #define FTRACE_RETFUNC_DEPTH 50
453 #define FTRACE_RETSTACK_ALLOC_SIZE 32
454 /* Type of the callback handlers for tracing function graph*/
455 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
456 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
458 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
459 trace_func_graph_ent_t entryfunc);
461 extern void ftrace_graph_stop(void);
463 /* The current handlers in use */
464 extern trace_func_graph_ret_t ftrace_graph_return;
465 extern trace_func_graph_ent_t ftrace_graph_entry;
467 extern void unregister_ftrace_graph(void);
469 extern void ftrace_graph_init_task(struct task_struct *t);
470 extern void ftrace_graph_exit_task(struct task_struct *t);
472 static inline int task_curr_ret_stack(struct task_struct *t)
474 return t->curr_ret_stack;
477 static inline void pause_graph_tracing(void)
479 atomic_inc(¤t->tracing_graph_pause);
482 static inline void unpause_graph_tracing(void)
484 atomic_dec(¤t->tracing_graph_pause);
488 #define __notrace_funcgraph
491 static inline void ftrace_graph_init_task(struct task_struct *t) { }
492 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
494 static inline int task_curr_ret_stack(struct task_struct *tsk)
499 static inline void pause_graph_tracing(void) { }
500 static inline void unpause_graph_tracing(void) { }
503 #ifdef CONFIG_TRACING
504 #include <linux/sched.h>
506 /* flags for current->trace */
508 TSK_TRACE_FL_TRACE_BIT = 0,
509 TSK_TRACE_FL_GRAPH_BIT = 1,
512 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
513 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
516 static inline void set_tsk_trace_trace(struct task_struct *tsk)
518 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
521 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
523 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
526 static inline int test_tsk_trace_trace(struct task_struct *tsk)
528 return tsk->trace & TSK_TRACE_FL_TRACE;
531 static inline void set_tsk_trace_graph(struct task_struct *tsk)
533 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
536 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
538 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
541 static inline int test_tsk_trace_graph(struct task_struct *tsk)
543 return tsk->trace & TSK_TRACE_FL_GRAPH;
546 #endif /* CONFIG_TRACING */
549 #ifdef CONFIG_HW_BRANCH_TRACER
551 void trace_hw_branch(u64 from, u64 to);
552 void trace_hw_branch_oops(void);
554 #else /* CONFIG_HW_BRANCH_TRACER */
556 static inline void trace_hw_branch(u64 from, u64 to) {}
557 static inline void trace_hw_branch_oops(void) {}
559 #endif /* CONFIG_HW_BRANCH_TRACER */
561 #endif /* _LINUX_FTRACE_H */