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);
226 /* May be defined in arch */
227 extern int ftrace_arch_read_dyn_info(char *buf, int size);
229 extern int skip_trace(unsigned long ip);
231 extern void ftrace_release(void *start, unsigned long size);
233 extern void ftrace_disable_daemon(void);
234 extern void ftrace_enable_daemon(void);
236 # define skip_trace(ip) ({ 0; })
237 # define ftrace_force_update() ({ 0; })
238 # define ftrace_set_filter(buf, len, reset) do { } while (0)
239 # define ftrace_disable_daemon() do { } while (0)
240 # define ftrace_enable_daemon() do { } while (0)
241 static inline void ftrace_release(void *start, unsigned long size) { }
242 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
246 static inline int unregister_ftrace_command(char *cmd_name)
250 #endif /* CONFIG_DYNAMIC_FTRACE */
252 /* totally disable ftrace - can not re-enable after this */
253 void ftrace_kill(void);
255 static inline void tracer_disable(void)
257 #ifdef CONFIG_FUNCTION_TRACER
263 * Ftrace disable/restore without lock. Some synchronization mechanism
264 * must be used to prevent ftrace_enabled to be changed between
267 static inline int __ftrace_enabled_save(void)
269 #ifdef CONFIG_FUNCTION_TRACER
270 int saved_ftrace_enabled = ftrace_enabled;
272 return saved_ftrace_enabled;
278 static inline void __ftrace_enabled_restore(int enabled)
280 #ifdef CONFIG_FUNCTION_TRACER
281 ftrace_enabled = enabled;
285 #ifndef HAVE_ARCH_CALLER_ADDR
286 # ifdef CONFIG_FRAME_POINTER
287 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
288 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
289 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
290 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
291 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
292 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
293 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
295 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
296 # define CALLER_ADDR1 0UL
297 # define CALLER_ADDR2 0UL
298 # define CALLER_ADDR3 0UL
299 # define CALLER_ADDR4 0UL
300 # define CALLER_ADDR5 0UL
301 # define CALLER_ADDR6 0UL
303 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
305 #ifdef CONFIG_IRQSOFF_TRACER
306 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
307 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
309 # define time_hardirqs_on(a0, a1) do { } while (0)
310 # define time_hardirqs_off(a0, a1) do { } while (0)
313 #ifdef CONFIG_PREEMPT_TRACER
314 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
315 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
317 # define trace_preempt_on(a0, a1) do { } while (0)
318 # define trace_preempt_off(a0, a1) do { } while (0)
321 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
322 extern void ftrace_init(void);
323 extern void ftrace_init_module(struct module *mod,
324 unsigned long *start, unsigned long *end);
326 static inline void ftrace_init(void) { }
328 ftrace_init_module(struct module *mod,
329 unsigned long *start, unsigned long *end) { }
333 * Structure that defines an entry function trace.
335 struct ftrace_graph_ent {
336 unsigned long func; /* Current function */
341 * Structure that defines a return function trace.
343 struct ftrace_graph_ret {
344 unsigned long func; /* Current function */
345 unsigned long long calltime;
346 unsigned long long rettime;
347 /* Number of functions that overran the depth limit for current task */
348 unsigned long overrun;
352 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
355 * Stack of return addresses for functions
357 * Used in struct thread_info
359 struct ftrace_ret_stack {
362 unsigned long long calltime;
366 * Primary handler of a function return.
367 * It relays on ftrace_return_to_handler.
368 * Defined in entry_32/64.S
370 extern void return_to_handler(void);
373 ftrace_push_return_trace(unsigned long ret, unsigned long long time,
374 unsigned long func, int *depth);
376 ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret);
379 * Sometimes we don't want to trace a function with the function
380 * graph tracer but we want them to keep traced by the usual function
381 * tracer if the function graph tracer is not configured.
383 #define __notrace_funcgraph notrace
386 * We want to which function is an entrypoint of a hardirq.
387 * That will help us to put a signal on output.
389 #define __irq_entry __attribute__((__section__(".irqentry.text")))
391 /* Limits of hardirq entrypoints */
392 extern char __irqentry_text_start[];
393 extern char __irqentry_text_end[];
395 #define FTRACE_RETFUNC_DEPTH 50
396 #define FTRACE_RETSTACK_ALLOC_SIZE 32
397 /* Type of the callback handlers for tracing function graph*/
398 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
399 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
401 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
402 trace_func_graph_ent_t entryfunc);
404 extern void ftrace_graph_stop(void);
406 /* The current handlers in use */
407 extern trace_func_graph_ret_t ftrace_graph_return;
408 extern trace_func_graph_ent_t ftrace_graph_entry;
410 extern void unregister_ftrace_graph(void);
412 extern void ftrace_graph_init_task(struct task_struct *t);
413 extern void ftrace_graph_exit_task(struct task_struct *t);
415 static inline int task_curr_ret_stack(struct task_struct *t)
417 return t->curr_ret_stack;
420 static inline void pause_graph_tracing(void)
422 atomic_inc(¤t->tracing_graph_pause);
425 static inline void unpause_graph_tracing(void)
427 atomic_dec(¤t->tracing_graph_pause);
431 #define __notrace_funcgraph
434 static inline void ftrace_graph_init_task(struct task_struct *t) { }
435 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
437 static inline int task_curr_ret_stack(struct task_struct *tsk)
442 static inline void pause_graph_tracing(void) { }
443 static inline void unpause_graph_tracing(void) { }
446 #ifdef CONFIG_TRACING
447 #include <linux/sched.h>
449 /* flags for current->trace */
451 TSK_TRACE_FL_TRACE_BIT = 0,
452 TSK_TRACE_FL_GRAPH_BIT = 1,
455 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
456 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
459 static inline void set_tsk_trace_trace(struct task_struct *tsk)
461 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
464 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
466 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
469 static inline int test_tsk_trace_trace(struct task_struct *tsk)
471 return tsk->trace & TSK_TRACE_FL_TRACE;
474 static inline void set_tsk_trace_graph(struct task_struct *tsk)
476 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
479 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
481 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
484 static inline int test_tsk_trace_graph(struct task_struct *tsk)
486 return tsk->trace & TSK_TRACE_FL_GRAPH;
489 extern int ftrace_dump_on_oops;
491 #endif /* CONFIG_TRACING */
494 #ifdef CONFIG_HW_BRANCH_TRACER
496 void trace_hw_branch(u64 from, u64 to);
497 void trace_hw_branch_oops(void);
499 #else /* CONFIG_HW_BRANCH_TRACER */
501 static inline void trace_hw_branch(u64 from, u64 to) {}
502 static inline void trace_hw_branch_oops(void) {}
504 #endif /* CONFIG_HW_BRANCH_TRACER */
507 * A syscall entry in the ftrace syscalls array.
509 * @name: name of the syscall
510 * @nb_args: number of parameters it takes
511 * @types: list of types as strings
512 * @args: list of args as strings (args[i] matches types[i])
514 struct syscall_metadata {
521 #ifdef CONFIG_FTRACE_SYSCALLS
522 extern void arch_init_ftrace_syscalls(void);
523 extern struct syscall_metadata *syscall_nr_to_meta(int nr);
524 extern void start_ftrace_syscalls(void);
525 extern void stop_ftrace_syscalls(void);
526 extern void ftrace_syscall_enter(struct pt_regs *regs);
527 extern void ftrace_syscall_exit(struct pt_regs *regs);
529 static inline void start_ftrace_syscalls(void) { }
530 static inline void stop_ftrace_syscalls(void) { }
531 static inline void ftrace_syscall_enter(struct pt_regs *regs) { }
532 static inline void ftrace_syscall_exit(struct pt_regs *regs) { }
535 #endif /* _LINUX_FTRACE_H */