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/kallsyms.h>
10 #include <linux/bitops.h>
12 #ifdef CONFIG_FUNCTION_TRACER
14 extern int ftrace_enabled;
16 ftrace_enable_sysctl(struct ctl_table *table, int write,
17 struct file *filp, void __user *buffer, size_t *lenp,
20 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
24 struct ftrace_ops *next;
27 extern int function_trace_stop;
30 * Type of the current tracing.
32 enum ftrace_tracing_type_t {
33 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
34 FTRACE_TYPE_RETURN, /* Hook the return of the function */
37 /* Current tracing type, default is FTRACE_TYPE_ENTER */
38 extern enum ftrace_tracing_type_t ftrace_tracing_type;
41 * ftrace_stop - stop function tracer.
43 * A quick way to stop the function tracer. Note this an on off switch,
44 * it is not something that is recursive like preempt_disable.
45 * This does not disable the calling of mcount, it only stops the
46 * calling of functions from mcount.
48 static inline void ftrace_stop(void)
50 function_trace_stop = 1;
54 * ftrace_start - start the function tracer.
56 * This function is the inverse of ftrace_stop. This does not enable
57 * the function tracing if the function tracer is disabled. This only
58 * sets the function tracer flag to continue calling the functions
61 static inline void ftrace_start(void)
63 function_trace_stop = 0;
67 * The ftrace_ops must be a static and should also
68 * be read_mostly. These functions do modify read_mostly variables
69 * so use them sparely. Never free an ftrace_op or modify the
70 * next pointer after it has been registered. Even after unregistering
71 * it, the next pointer may still be used internally.
73 int register_ftrace_function(struct ftrace_ops *ops);
74 int unregister_ftrace_function(struct ftrace_ops *ops);
75 void clear_ftrace_function(void);
77 extern void ftrace_stub(unsigned long a0, unsigned long a1);
79 #else /* !CONFIG_FUNCTION_TRACER */
80 # define register_ftrace_function(ops) do { } while (0)
81 # define unregister_ftrace_function(ops) do { } while (0)
82 # define clear_ftrace_function(ops) do { } while (0)
83 static inline void ftrace_kill(void) { }
84 static inline void ftrace_stop(void) { }
85 static inline void ftrace_start(void) { }
86 #endif /* CONFIG_FUNCTION_TRACER */
88 #ifdef CONFIG_DYNAMIC_FTRACE
89 /* asm/ftrace.h must be defined for archs supporting dynamic ftrace */
90 #include <asm/ftrace.h>
93 FTRACE_FL_FREE = (1 << 0),
94 FTRACE_FL_FAILED = (1 << 1),
95 FTRACE_FL_FILTER = (1 << 2),
96 FTRACE_FL_ENABLED = (1 << 3),
97 FTRACE_FL_NOTRACE = (1 << 4),
98 FTRACE_FL_CONVERTED = (1 << 5),
99 FTRACE_FL_FROZEN = (1 << 6),
103 struct list_head list;
104 unsigned long ip; /* address of mcount call-site */
106 struct dyn_arch_ftrace arch;
109 int ftrace_force_update(void);
110 void ftrace_set_filter(unsigned char *buf, int len, int reset);
112 /* defined in arch */
113 extern int ftrace_ip_converted(unsigned long ip);
114 extern int ftrace_dyn_arch_init(void *data);
115 extern int ftrace_update_ftrace_func(ftrace_func_t func);
116 extern void ftrace_caller(void);
117 extern void ftrace_call(void);
118 extern void mcount_call(void);
119 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
120 extern void ftrace_graph_caller(void);
121 extern int ftrace_enable_ftrace_graph_caller(void);
122 extern int ftrace_disable_ftrace_graph_caller(void);
124 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
125 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
129 * ftrace_make_nop - convert code into top
130 * @mod: module structure if called by module load initialization
131 * @rec: the mcount call site record
132 * @addr: the address that the call site should be calling
134 * This is a very sensitive operation and great care needs
135 * to be taken by the arch. The operation should carefully
136 * read the location, check to see if what is read is indeed
137 * what we expect it to be, and then on success of the compare,
138 * it should write to the location.
140 * The code segment at @rec->ip should be a caller to @addr
144 * -EFAULT on error reading the location
145 * -EINVAL on a failed compare of the contents
146 * -EPERM on error writing to the location
147 * Any other value will be considered a failure.
149 extern int ftrace_make_nop(struct module *mod,
150 struct dyn_ftrace *rec, unsigned long addr);
153 * ftrace_make_call - convert a nop call site into a call to addr
154 * @rec: the mcount call site record
155 * @addr: the address that the call site should call
157 * This is a very sensitive operation and great care needs
158 * to be taken by the arch. The operation should carefully
159 * read the location, check to see if what is read is indeed
160 * what we expect it to be, and then on success of the compare,
161 * it should write to the location.
163 * The code segment at @rec->ip should be a nop
167 * -EFAULT on error reading the location
168 * -EINVAL on a failed compare of the contents
169 * -EPERM on error writing to the location
170 * Any other value will be considered a failure.
172 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
175 /* May be defined in arch */
176 extern int ftrace_arch_read_dyn_info(char *buf, int size);
178 extern int skip_trace(unsigned long ip);
180 extern void ftrace_release(void *start, unsigned long size);
182 extern void ftrace_disable_daemon(void);
183 extern void ftrace_enable_daemon(void);
185 # define skip_trace(ip) ({ 0; })
186 # define ftrace_force_update() ({ 0; })
187 # define ftrace_set_filter(buf, len, reset) do { } while (0)
188 # define ftrace_disable_daemon() do { } while (0)
189 # define ftrace_enable_daemon() do { } while (0)
190 static inline void ftrace_release(void *start, unsigned long size) { }
191 #endif /* CONFIG_DYNAMIC_FTRACE */
193 /* totally disable ftrace - can not re-enable after this */
194 void ftrace_kill(void);
196 static inline void tracer_disable(void)
198 #ifdef CONFIG_FUNCTION_TRACER
204 * Ftrace disable/restore without lock. Some synchronization mechanism
205 * must be used to prevent ftrace_enabled to be changed between
208 static inline int __ftrace_enabled_save(void)
210 #ifdef CONFIG_FUNCTION_TRACER
211 int saved_ftrace_enabled = ftrace_enabled;
213 return saved_ftrace_enabled;
219 static inline void __ftrace_enabled_restore(int enabled)
221 #ifdef CONFIG_FUNCTION_TRACER
222 ftrace_enabled = enabled;
226 #ifdef CONFIG_FRAME_POINTER
227 /* TODO: need to fix this for ARM */
228 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
229 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
230 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
231 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
232 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
233 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
234 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
236 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
237 # define CALLER_ADDR1 0UL
238 # define CALLER_ADDR2 0UL
239 # define CALLER_ADDR3 0UL
240 # define CALLER_ADDR4 0UL
241 # define CALLER_ADDR5 0UL
242 # define CALLER_ADDR6 0UL
245 #ifdef CONFIG_IRQSOFF_TRACER
246 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
247 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
249 # define time_hardirqs_on(a0, a1) do { } while (0)
250 # define time_hardirqs_off(a0, a1) do { } while (0)
253 #ifdef CONFIG_PREEMPT_TRACER
254 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
255 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
257 # define trace_preempt_on(a0, a1) do { } while (0)
258 # define trace_preempt_off(a0, a1) do { } while (0)
261 #ifdef CONFIG_TRACING
262 extern int ftrace_dump_on_oops;
264 extern void tracing_start(void);
265 extern void tracing_stop(void);
266 extern void ftrace_off_permanent(void);
269 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
272 * ftrace_printk - printf formatting in the ftrace buffer
273 * @fmt: the printf format for printing
275 * Note: __ftrace_printk is an internal function for ftrace_printk and
276 * the @ip is passed in via the ftrace_printk macro.
278 * This function allows a kernel developer to debug fast path sections
279 * that printk is not appropriate for. By scattering in various
280 * printk like tracing in the code, a developer can quickly see
281 * where problems are occurring.
283 * This is intended as a debugging tool for the developer only.
284 * Please refrain from leaving ftrace_printks scattered around in
287 # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
289 __ftrace_printk(unsigned long ip, const char *fmt, ...)
290 __attribute__ ((format (printf, 2, 3)));
291 extern void ftrace_dump(void);
294 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
296 ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 0)));
298 static inline void tracing_start(void) { }
299 static inline void tracing_stop(void) { }
300 static inline void ftrace_off_permanent(void) { }
302 ftrace_printk(const char *fmt, ...)
306 static inline void ftrace_dump(void) { }
309 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
310 extern void ftrace_init(void);
311 extern void ftrace_init_module(struct module *mod,
312 unsigned long *start, unsigned long *end);
314 static inline void ftrace_init(void) { }
316 ftrace_init_module(struct module *mod,
317 unsigned long *start, unsigned long *end) { }
327 #ifdef CONFIG_POWER_TRACER
335 #ifdef CONFIG_POWER_TRACER
336 extern void trace_power_start(struct power_trace *it, unsigned int type,
338 extern void trace_power_mark(struct power_trace *it, unsigned int type,
340 extern void trace_power_end(struct power_trace *it);
342 static inline void trace_power_start(struct power_trace *it, unsigned int type,
343 unsigned int state) { }
344 static inline void trace_power_mark(struct power_trace *it, unsigned int type,
345 unsigned int state) { }
346 static inline void trace_power_end(struct power_trace *it) { }
351 * Structure that defines an entry function trace.
353 struct ftrace_graph_ent {
354 unsigned long func; /* Current function */
359 * Structure that defines a return function trace.
361 struct ftrace_graph_ret {
362 unsigned long func; /* Current function */
363 unsigned long long calltime;
364 unsigned long long rettime;
365 /* Number of functions that overran the depth limit for current task */
366 unsigned long overrun;
370 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
371 #define FTRACE_RETFUNC_DEPTH 50
372 #define FTRACE_RETSTACK_ALLOC_SIZE 32
373 /* Type of the callback handlers for tracing function graph*/
374 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
375 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
377 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
378 trace_func_graph_ent_t entryfunc);
380 extern void ftrace_graph_stop(void);
382 /* The current handlers in use */
383 extern trace_func_graph_ret_t ftrace_graph_return;
384 extern trace_func_graph_ent_t ftrace_graph_entry;
386 extern void unregister_ftrace_graph(void);
388 extern void ftrace_graph_init_task(struct task_struct *t);
389 extern void ftrace_graph_exit_task(struct task_struct *t);
391 static inline void ftrace_graph_init_task(struct task_struct *t) { }
392 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
395 #ifdef CONFIG_TRACING
396 #include <linux/sched.h>
398 /* flags for current->trace */
400 TSK_TRACE_FL_TRACE_BIT = 0,
401 TSK_TRACE_FL_GRAPH_BIT = 1,
404 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
405 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
408 static inline void set_tsk_trace_trace(struct task_struct *tsk)
410 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
413 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
415 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
418 static inline int test_tsk_trace_trace(struct task_struct *tsk)
420 return tsk->trace & TSK_TRACE_FL_TRACE;
423 static inline void set_tsk_trace_graph(struct task_struct *tsk)
425 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
428 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
430 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
433 static inline int test_tsk_trace_graph(struct task_struct *tsk)
435 return tsk->trace & TSK_TRACE_FL_GRAPH;
438 #endif /* CONFIG_TRACING */
440 #endif /* _LINUX_FTRACE_H */