1 #ifndef _LINUX_FTRACE_H
2 #define _LINUX_FTRACE_H
4 #include <linux/linkage.h>
6 #include <linux/ktime.h>
7 #include <linux/init.h>
8 #include <linux/types.h>
9 #include <linux/module.h>
10 #include <linux/kallsyms.h>
11 #include <linux/bitops.h>
12 #include <linux/sched.h>
14 #ifdef CONFIG_FUNCTION_TRACER
16 extern int ftrace_enabled;
18 ftrace_enable_sysctl(struct ctl_table *table, int write,
19 struct file *filp, void __user *buffer, size_t *lenp,
22 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
26 struct ftrace_ops *next;
29 extern int function_trace_stop;
32 * Type of the current tracing.
34 enum ftrace_tracing_type_t {
35 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
36 FTRACE_TYPE_RETURN, /* Hook the return of the function */
39 /* Current tracing type, default is FTRACE_TYPE_ENTER */
40 extern enum ftrace_tracing_type_t ftrace_tracing_type;
43 * ftrace_stop - stop function tracer.
45 * A quick way to stop the function tracer. Note this an on off switch,
46 * it is not something that is recursive like preempt_disable.
47 * This does not disable the calling of mcount, it only stops the
48 * calling of functions from mcount.
50 static inline void ftrace_stop(void)
52 function_trace_stop = 1;
56 * ftrace_start - start the function tracer.
58 * This function is the inverse of ftrace_stop. This does not enable
59 * the function tracing if the function tracer is disabled. This only
60 * sets the function tracer flag to continue calling the functions
63 static inline void ftrace_start(void)
65 function_trace_stop = 0;
69 * The ftrace_ops must be a static and should also
70 * be read_mostly. These functions do modify read_mostly variables
71 * so use them sparely. Never free an ftrace_op or modify the
72 * next pointer after it has been registered. Even after unregistering
73 * it, the next pointer may still be used internally.
75 int register_ftrace_function(struct ftrace_ops *ops);
76 int unregister_ftrace_function(struct ftrace_ops *ops);
77 void clear_ftrace_function(void);
79 extern void ftrace_stub(unsigned long a0, unsigned long a1);
81 #else /* !CONFIG_FUNCTION_TRACER */
82 # define register_ftrace_function(ops) do { } while (0)
83 # define unregister_ftrace_function(ops) do { } while (0)
84 # define clear_ftrace_function(ops) do { } while (0)
85 static inline void ftrace_kill(void) { }
86 static inline void ftrace_stop(void) { }
87 static inline void ftrace_start(void) { }
88 #endif /* CONFIG_FUNCTION_TRACER */
90 #ifdef CONFIG_STACK_TRACER
91 extern int stack_tracer_enabled;
93 stack_trace_sysctl(struct ctl_table *table, int write,
94 struct file *file, void __user *buffer, size_t *lenp,
98 #ifdef CONFIG_DYNAMIC_FTRACE
99 /* asm/ftrace.h must be defined for archs supporting dynamic ftrace */
100 #include <asm/ftrace.h>
102 int ftrace_arch_code_modify_prepare(void);
103 int ftrace_arch_code_modify_post_process(void);
106 FTRACE_FL_FREE = (1 << 0),
107 FTRACE_FL_FAILED = (1 << 1),
108 FTRACE_FL_FILTER = (1 << 2),
109 FTRACE_FL_ENABLED = (1 << 3),
110 FTRACE_FL_NOTRACE = (1 << 4),
111 FTRACE_FL_CONVERTED = (1 << 5),
112 FTRACE_FL_FROZEN = (1 << 6),
116 struct list_head list;
117 unsigned long ip; /* address of mcount call-site */
119 struct dyn_arch_ftrace arch;
122 int ftrace_force_update(void);
123 void ftrace_set_filter(unsigned char *buf, int len, int reset);
125 /* defined in arch */
126 extern int ftrace_ip_converted(unsigned long ip);
127 extern int ftrace_dyn_arch_init(void *data);
128 extern int ftrace_update_ftrace_func(ftrace_func_t func);
129 extern void ftrace_caller(void);
130 extern void ftrace_call(void);
131 extern void mcount_call(void);
132 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
133 extern void ftrace_graph_caller(void);
134 extern int ftrace_enable_ftrace_graph_caller(void);
135 extern int ftrace_disable_ftrace_graph_caller(void);
137 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
138 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
142 * ftrace_make_nop - convert code into top
143 * @mod: module structure if called by module load initialization
144 * @rec: the mcount call site record
145 * @addr: the address that the call site should be calling
147 * This is a very sensitive operation and great care needs
148 * to be taken by the arch. The operation should carefully
149 * read the location, check to see if what is read is indeed
150 * what we expect it to be, and then on success of the compare,
151 * it should write to the location.
153 * The code segment at @rec->ip should be a caller to @addr
157 * -EFAULT on error reading the location
158 * -EINVAL on a failed compare of the contents
159 * -EPERM on error writing to the location
160 * Any other value will be considered a failure.
162 extern int ftrace_make_nop(struct module *mod,
163 struct dyn_ftrace *rec, unsigned long addr);
166 * ftrace_make_call - convert a nop call site into a call to addr
167 * @rec: the mcount call site record
168 * @addr: the address that the call site should call
170 * This is a very sensitive operation and great care needs
171 * to be taken by the arch. The operation should carefully
172 * read the location, check to see if what is read is indeed
173 * what we expect it to be, and then on success of the compare,
174 * it should write to the location.
176 * The code segment at @rec->ip should be a nop
180 * -EFAULT on error reading the location
181 * -EINVAL on a failed compare of the contents
182 * -EPERM on error writing to the location
183 * Any other value will be considered a failure.
185 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
188 /* May be defined in arch */
189 extern int ftrace_arch_read_dyn_info(char *buf, int size);
191 extern int skip_trace(unsigned long ip);
193 extern void ftrace_release(void *start, unsigned long size);
195 extern void ftrace_disable_daemon(void);
196 extern void ftrace_enable_daemon(void);
198 # define skip_trace(ip) ({ 0; })
199 # define ftrace_force_update() ({ 0; })
200 # define ftrace_set_filter(buf, len, reset) do { } while (0)
201 # define ftrace_disable_daemon() do { } while (0)
202 # define ftrace_enable_daemon() do { } while (0)
203 static inline void ftrace_release(void *start, unsigned long size) { }
204 #endif /* CONFIG_DYNAMIC_FTRACE */
206 /* totally disable ftrace - can not re-enable after this */
207 void ftrace_kill(void);
209 static inline void tracer_disable(void)
211 #ifdef CONFIG_FUNCTION_TRACER
217 * Ftrace disable/restore without lock. Some synchronization mechanism
218 * must be used to prevent ftrace_enabled to be changed between
221 static inline int __ftrace_enabled_save(void)
223 #ifdef CONFIG_FUNCTION_TRACER
224 int saved_ftrace_enabled = ftrace_enabled;
226 return saved_ftrace_enabled;
232 static inline void __ftrace_enabled_restore(int enabled)
234 #ifdef CONFIG_FUNCTION_TRACER
235 ftrace_enabled = enabled;
239 #ifdef CONFIG_FRAME_POINTER
240 /* TODO: need to fix this for ARM */
241 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
242 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
243 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
244 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
245 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
246 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
247 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
249 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
250 # define CALLER_ADDR1 0UL
251 # define CALLER_ADDR2 0UL
252 # define CALLER_ADDR3 0UL
253 # define CALLER_ADDR4 0UL
254 # define CALLER_ADDR5 0UL
255 # define CALLER_ADDR6 0UL
258 #ifdef CONFIG_IRQSOFF_TRACER
259 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
260 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
262 # define time_hardirqs_on(a0, a1) do { } while (0)
263 # define time_hardirqs_off(a0, a1) do { } while (0)
266 #ifdef CONFIG_PREEMPT_TRACER
267 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
268 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
270 # define trace_preempt_on(a0, a1) do { } while (0)
271 # define trace_preempt_off(a0, a1) do { } while (0)
274 #ifdef CONFIG_TRACING
275 extern int ftrace_dump_on_oops;
277 extern void tracing_start(void);
278 extern void tracing_stop(void);
279 extern void ftrace_off_permanent(void);
282 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
285 * ftrace_printk - printf formatting in the ftrace buffer
286 * @fmt: the printf format for printing
288 * Note: __ftrace_printk is an internal function for ftrace_printk and
289 * the @ip is passed in via the ftrace_printk macro.
291 * This function allows a kernel developer to debug fast path sections
292 * that printk is not appropriate for. By scattering in various
293 * printk like tracing in the code, a developer can quickly see
294 * where problems are occurring.
296 * This is intended as a debugging tool for the developer only.
297 * Please refrain from leaving ftrace_printks scattered around in
300 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
302 __ftrace_printk(unsigned long ip, const char *fmt, ...)
303 __attribute__ ((format (printf, 2, 3)));
304 extern void ftrace_dump(void);
307 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
309 ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
311 static inline void tracing_start(void) { }
312 static inline void tracing_stop(void) { }
313 static inline void ftrace_off_permanent(void) { }
315 ftrace_printk(const char *fmt, ...)
319 static inline void ftrace_dump(void) { }
322 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
323 extern void ftrace_init(void);
324 extern void ftrace_init_module(struct module *mod,
325 unsigned long *start, unsigned long *end);
327 static inline void ftrace_init(void) { }
329 ftrace_init_module(struct module *mod,
330 unsigned long *start, unsigned long *end) { }
340 #ifdef CONFIG_POWER_TRACER
348 #ifdef CONFIG_POWER_TRACER
349 extern void trace_power_start(struct power_trace *it, unsigned int type,
351 extern void trace_power_mark(struct power_trace *it, unsigned int type,
353 extern void trace_power_end(struct power_trace *it);
355 static inline void trace_power_start(struct power_trace *it, unsigned int type,
356 unsigned int state) { }
357 static inline void trace_power_mark(struct power_trace *it, unsigned int type,
358 unsigned int state) { }
359 static inline void trace_power_end(struct power_trace *it) { }
364 * Structure that defines an entry function trace.
366 struct ftrace_graph_ent {
367 unsigned long func; /* Current function */
372 * Structure that defines a return function trace.
374 struct ftrace_graph_ret {
375 unsigned long func; /* Current function */
376 unsigned long long calltime;
377 unsigned long long rettime;
378 /* Number of functions that overran the depth limit for current task */
379 unsigned long overrun;
383 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
386 * Sometimes we don't want to trace a function with the function
387 * graph tracer but we want them to keep traced by the usual function
388 * tracer if the function graph tracer is not configured.
390 #define __notrace_funcgraph notrace
393 * We want to which function is an entrypoint of a hardirq.
394 * That will help us to put a signal on output.
396 #define __irq_entry __attribute__((__section__(".irqentry.text")))
398 /* Limits of hardirq entrypoints */
399 extern char __irqentry_text_start[];
400 extern char __irqentry_text_end[];
402 #define FTRACE_RETFUNC_DEPTH 50
403 #define FTRACE_RETSTACK_ALLOC_SIZE 32
404 /* Type of the callback handlers for tracing function graph*/
405 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
406 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
408 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
409 trace_func_graph_ent_t entryfunc);
411 extern void ftrace_graph_stop(void);
413 /* The current handlers in use */
414 extern trace_func_graph_ret_t ftrace_graph_return;
415 extern trace_func_graph_ent_t ftrace_graph_entry;
417 extern void unregister_ftrace_graph(void);
419 extern void ftrace_graph_init_task(struct task_struct *t);
420 extern void ftrace_graph_exit_task(struct task_struct *t);
422 static inline int task_curr_ret_stack(struct task_struct *t)
424 return t->curr_ret_stack;
427 static inline void pause_graph_tracing(void)
429 atomic_inc(¤t->tracing_graph_pause);
432 static inline void unpause_graph_tracing(void)
434 atomic_dec(¤t->tracing_graph_pause);
438 #define __notrace_funcgraph
441 static inline void ftrace_graph_init_task(struct task_struct *t) { }
442 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
444 static inline int task_curr_ret_stack(struct task_struct *tsk)
449 static inline void pause_graph_tracing(void) { }
450 static inline void unpause_graph_tracing(void) { }
453 #ifdef CONFIG_TRACING
454 #include <linux/sched.h>
456 /* flags for current->trace */
458 TSK_TRACE_FL_TRACE_BIT = 0,
459 TSK_TRACE_FL_GRAPH_BIT = 1,
462 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
463 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
466 static inline void set_tsk_trace_trace(struct task_struct *tsk)
468 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
471 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
473 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
476 static inline int test_tsk_trace_trace(struct task_struct *tsk)
478 return tsk->trace & TSK_TRACE_FL_TRACE;
481 static inline void set_tsk_trace_graph(struct task_struct *tsk)
483 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
486 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
488 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
491 static inline int test_tsk_trace_graph(struct task_struct *tsk)
493 return tsk->trace & TSK_TRACE_FL_GRAPH;
496 #endif /* CONFIG_TRACING */
498 #endif /* _LINUX_FTRACE_H */