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/ptrace.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>
23 * If the arch supports passing the variable contents of
24 * function_trace_op as the third parameter back from the
25 * mcount call, then the arch should define this as 1.
27 #ifndef ARCH_SUPPORTS_FTRACE_OPS
28 #define ARCH_SUPPORTS_FTRACE_OPS 0
32 * If the arch's mcount caller does not support all of ftrace's
33 * features, then it must call an indirect function that
34 * does. Or at least does enough to prevent any unwelcomed side effects.
36 #if !ARCH_SUPPORTS_FTRACE_OPS
37 # define FTRACE_FORCE_LIST_FUNC 1
39 # define FTRACE_FORCE_LIST_FUNC 0
46 #ifdef CONFIG_FUNCTION_TRACER
48 extern int ftrace_enabled;
50 ftrace_enable_sysctl(struct ctl_table *table, int write,
51 void __user *buffer, size_t *lenp,
56 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
57 struct ftrace_ops *op, struct pt_regs *regs);
60 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
61 * set in the flags member.
63 * ENABLED - set/unset when ftrace_ops is registered/unregistered
64 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
65 * allocated ftrace_ops which need special care
66 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
67 * could be controled by following calls:
68 * ftrace_function_local_enable
69 * ftrace_function_local_disable
70 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
71 * and passed to the callback. If this flag is set, but the
72 * architecture does not support passing regs
73 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
74 * ftrace_ops will fail to register, unless the next flag
76 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
77 * handler can handle an arch that does not save regs
78 * (the handler tests if regs == NULL), then it can set
79 * this flag instead. It will not fail registering the ftrace_ops
80 * but, the regs field will be NULL if the arch does not support
81 * passing regs to the handler.
82 * Note, if this flag is set, the SAVE_REGS flag will automatically
83 * get set upon registering the ftrace_ops, if the arch supports it.
84 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
85 * that the call back has its own recursion protection. If it does
86 * not set this, then the ftrace infrastructure will add recursion
87 * protection for the caller.
88 * STUB - The ftrace_ops is just a place holder.
89 * INITIALIZED - The ftrace_ops has already been initialized (first use time
90 * register_ftrace_function() is called, it will initialized the ops)
91 * DELETED - The ops are being deleted, do not let them be registered again.
94 FTRACE_OPS_FL_ENABLED = 1 << 0,
95 FTRACE_OPS_FL_DYNAMIC = 1 << 1,
96 FTRACE_OPS_FL_CONTROL = 1 << 2,
97 FTRACE_OPS_FL_SAVE_REGS = 1 << 3,
98 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4,
99 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5,
100 FTRACE_OPS_FL_STUB = 1 << 6,
101 FTRACE_OPS_FL_INITIALIZED = 1 << 7,
102 FTRACE_OPS_FL_DELETED = 1 << 8,
106 * Note, ftrace_ops can be referenced outside of RCU protection.
107 * (Although, for perf, the control ops prevent that). If ftrace_ops is
108 * allocated and not part of kernel core data, the unregistering of it will
109 * perform a scheduling on all CPUs to make sure that there are no more users.
110 * Depending on the load of the system that may take a bit of time.
112 * Any private data added must also take care not to be freed and if private
113 * data is added to a ftrace_ops that is in core code, the user of the
114 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
118 struct ftrace_ops *next;
121 int __percpu *disabled;
122 #ifdef CONFIG_DYNAMIC_FTRACE
124 struct ftrace_hash *notrace_hash;
125 struct ftrace_hash *filter_hash;
126 struct ftrace_hash *tramp_hash;
127 struct mutex regex_lock;
128 unsigned long trampoline;
133 * Type of the current tracing.
135 enum ftrace_tracing_type_t {
136 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
137 FTRACE_TYPE_RETURN, /* Hook the return of the function */
140 /* Current tracing type, default is FTRACE_TYPE_ENTER */
141 extern enum ftrace_tracing_type_t ftrace_tracing_type;
144 * The ftrace_ops must be a static and should also
145 * be read_mostly. These functions do modify read_mostly variables
146 * so use them sparely. Never free an ftrace_op or modify the
147 * next pointer after it has been registered. Even after unregistering
148 * it, the next pointer may still be used internally.
150 int register_ftrace_function(struct ftrace_ops *ops);
151 int unregister_ftrace_function(struct ftrace_ops *ops);
152 void clear_ftrace_function(void);
155 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
157 * This function enables tracing on current cpu by decreasing
158 * the per cpu control variable.
159 * It must be called with preemption disabled and only on ftrace_ops
160 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
161 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
163 static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
165 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
168 (*this_cpu_ptr(ops->disabled))--;
172 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
174 * This function enables tracing on current cpu by decreasing
175 * the per cpu control variable.
176 * It must be called with preemption disabled and only on ftrace_ops
177 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
178 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
180 static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
182 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
185 (*this_cpu_ptr(ops->disabled))++;
189 * ftrace_function_local_disabled - returns ftrace_ops disabled value
192 * This function returns value of ftrace_ops::disabled on current cpu.
193 * It must be called with preemption disabled and only on ftrace_ops
194 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
195 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
197 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
199 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
200 return *this_cpu_ptr(ops->disabled);
203 extern void ftrace_stub(unsigned long a0, unsigned long a1,
204 struct ftrace_ops *op, struct pt_regs *regs);
206 #else /* !CONFIG_FUNCTION_TRACER */
208 * (un)register_ftrace_function must be a macro since the ops parameter
209 * must not be evaluated.
211 #define register_ftrace_function(ops) ({ 0; })
212 #define unregister_ftrace_function(ops) ({ 0; })
213 static inline int ftrace_nr_registered_ops(void)
217 static inline void clear_ftrace_function(void) { }
218 static inline void ftrace_kill(void) { }
219 #endif /* CONFIG_FUNCTION_TRACER */
221 #ifdef CONFIG_STACK_TRACER
222 extern int stack_tracer_enabled;
224 stack_trace_sysctl(struct ctl_table *table, int write,
225 void __user *buffer, size_t *lenp,
229 struct ftrace_func_command {
230 struct list_head list;
232 int (*func)(struct ftrace_hash *hash,
233 char *func, char *cmd,
234 char *params, int enable);
237 #ifdef CONFIG_DYNAMIC_FTRACE
239 int ftrace_arch_code_modify_prepare(void);
240 int ftrace_arch_code_modify_post_process(void);
242 void ftrace_bug(int err, unsigned long ip);
246 struct ftrace_probe_ops {
247 void (*func)(unsigned long ip,
248 unsigned long parent_ip,
250 int (*init)(struct ftrace_probe_ops *ops,
251 unsigned long ip, void **data);
252 void (*free)(struct ftrace_probe_ops *ops,
253 unsigned long ip, void **data);
254 int (*print)(struct seq_file *m,
256 struct ftrace_probe_ops *ops,
261 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
264 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
267 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
268 extern void unregister_ftrace_function_probe_all(char *glob);
270 extern int ftrace_text_reserved(const void *start, const void *end);
272 extern int ftrace_nr_registered_ops(void);
275 * The dyn_ftrace record's flags field is split into two parts.
276 * the first part which is '0-FTRACE_REF_MAX' is a counter of
277 * the number of callbacks that have registered the function that
278 * the dyn_ftrace descriptor represents.
280 * The second part is a mask:
281 * ENABLED - the function is being traced
282 * REGS - the record wants the function to save regs
283 * REGS_EN - the function is set up to save regs.
285 * When a new ftrace_ops is registered and wants a function to save
286 * pt_regs, the rec->flag REGS is set. When the function has been
287 * set up to save regs, the REG_EN flag is set. Once a function
288 * starts saving regs it will do so until all ftrace_ops are removed
289 * from tracing that function.
292 FTRACE_FL_ENABLED = (1UL << 31),
293 FTRACE_FL_REGS = (1UL << 30),
294 FTRACE_FL_REGS_EN = (1UL << 29),
295 FTRACE_FL_TRAMP = (1UL << 28),
296 FTRACE_FL_TRAMP_EN = (1UL << 27),
299 #define FTRACE_REF_MAX_SHIFT 27
300 #define FTRACE_FL_BITS 5
301 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
302 #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
303 #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
305 #define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK)
308 unsigned long ip; /* address of mcount call-site */
310 struct dyn_arch_ftrace arch;
313 int ftrace_force_update(void);
314 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
315 int remove, int reset);
316 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
318 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
320 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
321 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
322 void ftrace_free_filter(struct ftrace_ops *ops);
324 int register_ftrace_command(struct ftrace_func_command *cmd);
325 int unregister_ftrace_command(struct ftrace_func_command *cmd);
328 FTRACE_UPDATE_CALLS = (1 << 0),
329 FTRACE_DISABLE_CALLS = (1 << 1),
330 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
331 FTRACE_START_FUNC_RET = (1 << 3),
332 FTRACE_STOP_FUNC_RET = (1 << 4),
336 * The FTRACE_UPDATE_* enum is used to pass information back
337 * from the ftrace_update_record() and ftrace_test_record()
338 * functions. These are called by the code update routines
339 * to find out what is to be done for a given function.
341 * IGNORE - The function is already what we want it to be
342 * MAKE_CALL - Start tracing the function
343 * MODIFY_CALL - Stop saving regs for the function
344 * MAKE_NOP - Stop tracing the function
347 FTRACE_UPDATE_IGNORE,
348 FTRACE_UPDATE_MAKE_CALL,
349 FTRACE_UPDATE_MODIFY_CALL,
350 FTRACE_UPDATE_MAKE_NOP,
354 FTRACE_ITER_FILTER = (1 << 0),
355 FTRACE_ITER_NOTRACE = (1 << 1),
356 FTRACE_ITER_PRINTALL = (1 << 2),
357 FTRACE_ITER_DO_HASH = (1 << 3),
358 FTRACE_ITER_HASH = (1 << 4),
359 FTRACE_ITER_ENABLED = (1 << 5),
362 void arch_ftrace_update_code(int command);
364 struct ftrace_rec_iter;
366 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
367 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
368 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
370 #define for_ftrace_rec_iter(iter) \
371 for (iter = ftrace_rec_iter_start(); \
373 iter = ftrace_rec_iter_next(iter))
376 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
377 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
378 void ftrace_run_stop_machine(int command);
379 unsigned long ftrace_location(unsigned long ip);
380 unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
381 unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
383 extern ftrace_func_t ftrace_trace_function;
385 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
386 struct inode *inode, struct file *file);
387 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
388 size_t cnt, loff_t *ppos);
389 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
390 size_t cnt, loff_t *ppos);
391 int ftrace_regex_release(struct inode *inode, struct file *file);
394 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
396 /* defined in arch */
397 extern int ftrace_ip_converted(unsigned long ip);
398 extern int ftrace_dyn_arch_init(void);
399 extern void ftrace_replace_code(int enable);
400 extern int ftrace_update_ftrace_func(ftrace_func_t func);
401 extern void ftrace_caller(void);
402 extern void ftrace_regs_caller(void);
403 extern void ftrace_call(void);
404 extern void ftrace_regs_call(void);
405 extern void mcount_call(void);
407 void ftrace_modify_all_code(int command);
410 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
413 #ifndef FTRACE_GRAPH_ADDR
414 #define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
417 #ifndef FTRACE_REGS_ADDR
418 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
419 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
421 # define FTRACE_REGS_ADDR FTRACE_ADDR
426 * If an arch would like functions that are only traced
427 * by the function graph tracer to jump directly to its own
428 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
429 * to be that address to jump to.
431 #ifndef FTRACE_GRAPH_TRAMP_ADDR
432 #define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
435 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
436 extern void ftrace_graph_caller(void);
437 extern int ftrace_enable_ftrace_graph_caller(void);
438 extern int ftrace_disable_ftrace_graph_caller(void);
440 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
441 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
445 * ftrace_make_nop - convert code into nop
446 * @mod: module structure if called by module load initialization
447 * @rec: the mcount call site record
448 * @addr: the address that the call site should be calling
450 * This is a very sensitive operation and great care needs
451 * to be taken by the arch. The operation should carefully
452 * read the location, check to see if what is read is indeed
453 * what we expect it to be, and then on success of the compare,
454 * it should write to the location.
456 * The code segment at @rec->ip should be a caller to @addr
460 * -EFAULT on error reading the location
461 * -EINVAL on a failed compare of the contents
462 * -EPERM on error writing to the location
463 * Any other value will be considered a failure.
465 extern int ftrace_make_nop(struct module *mod,
466 struct dyn_ftrace *rec, unsigned long addr);
469 * ftrace_make_call - convert a nop call site into a call to addr
470 * @rec: the mcount call site record
471 * @addr: the address that the call site should call
473 * This is a very sensitive operation and great care needs
474 * to be taken by the arch. The operation should carefully
475 * read the location, check to see if what is read is indeed
476 * what we expect it to be, and then on success of the compare,
477 * it should write to the location.
479 * The code segment at @rec->ip should be a nop
483 * -EFAULT on error reading the location
484 * -EINVAL on a failed compare of the contents
485 * -EPERM on error writing to the location
486 * Any other value will be considered a failure.
488 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
490 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
492 * ftrace_modify_call - convert from one addr to another (no nop)
493 * @rec: the mcount call site record
494 * @old_addr: the address expected to be currently called to
495 * @addr: the address to change to
497 * This is a very sensitive operation and great care needs
498 * to be taken by the arch. The operation should carefully
499 * read the location, check to see if what is read is indeed
500 * what we expect it to be, and then on success of the compare,
501 * it should write to the location.
503 * The code segment at @rec->ip should be a caller to @old_addr
507 * -EFAULT on error reading the location
508 * -EINVAL on a failed compare of the contents
509 * -EPERM on error writing to the location
510 * Any other value will be considered a failure.
512 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
515 /* Should never be called */
516 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
523 /* May be defined in arch */
524 extern int ftrace_arch_read_dyn_info(char *buf, int size);
526 extern int skip_trace(unsigned long ip);
527 extern void ftrace_module_init(struct module *mod);
529 extern void ftrace_disable_daemon(void);
530 extern void ftrace_enable_daemon(void);
531 #else /* CONFIG_DYNAMIC_FTRACE */
532 static inline int skip_trace(unsigned long ip) { return 0; }
533 static inline int ftrace_force_update(void) { return 0; }
534 static inline void ftrace_disable_daemon(void) { }
535 static inline void ftrace_enable_daemon(void) { }
536 static inline void ftrace_release_mod(struct module *mod) {}
537 static inline void ftrace_module_init(struct module *mod) {}
538 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
542 static inline __init int unregister_ftrace_command(char *cmd_name)
546 static inline int ftrace_text_reserved(const void *start, const void *end)
550 static inline unsigned long ftrace_location(unsigned long ip)
556 * Again users of functions that have ftrace_ops may not
557 * have them defined when ftrace is not enabled, but these
558 * functions may still be called. Use a macro instead of inline.
560 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
561 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
562 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
563 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
564 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
565 #define ftrace_free_filter(ops) do { } while (0)
567 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
568 size_t cnt, loff_t *ppos) { return -ENODEV; }
569 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
570 size_t cnt, loff_t *ppos) { return -ENODEV; }
572 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
573 #endif /* CONFIG_DYNAMIC_FTRACE */
575 /* totally disable ftrace - can not re-enable after this */
576 void ftrace_kill(void);
578 static inline void tracer_disable(void)
580 #ifdef CONFIG_FUNCTION_TRACER
586 * Ftrace disable/restore without lock. Some synchronization mechanism
587 * must be used to prevent ftrace_enabled to be changed between
590 static inline int __ftrace_enabled_save(void)
592 #ifdef CONFIG_FUNCTION_TRACER
593 int saved_ftrace_enabled = ftrace_enabled;
595 return saved_ftrace_enabled;
601 static inline void __ftrace_enabled_restore(int enabled)
603 #ifdef CONFIG_FUNCTION_TRACER
604 ftrace_enabled = enabled;
608 /* All archs should have this, but we define it for consistency */
609 #ifndef ftrace_return_address0
610 # define ftrace_return_address0 __builtin_return_address(0)
613 /* Archs may use other ways for ADDR1 and beyond */
614 #ifndef ftrace_return_address
615 # ifdef CONFIG_FRAME_POINTER
616 # define ftrace_return_address(n) __builtin_return_address(n)
618 # define ftrace_return_address(n) 0UL
622 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
623 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
624 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
625 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
626 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
627 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
628 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
630 #ifdef CONFIG_IRQSOFF_TRACER
631 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
632 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
634 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
635 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
638 #ifdef CONFIG_PREEMPT_TRACER
639 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
640 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
643 * Use defines instead of static inlines because some arches will make code out
644 * of the CALLER_ADDR, when we really want these to be a real nop.
646 # define trace_preempt_on(a0, a1) do { } while (0)
647 # define trace_preempt_off(a0, a1) do { } while (0)
650 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
651 extern void ftrace_init(void);
653 static inline void ftrace_init(void) { }
657 * Structure that defines an entry function trace.
659 struct ftrace_graph_ent {
660 unsigned long func; /* Current function */
665 * Structure that defines a return function trace.
667 struct ftrace_graph_ret {
668 unsigned long func; /* Current function */
669 unsigned long long calltime;
670 unsigned long long rettime;
671 /* Number of functions that overran the depth limit for current task */
672 unsigned long overrun;
676 /* Type of the callback handlers for tracing function graph*/
677 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
678 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
680 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
683 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
686 * Stack of return addresses for functions
688 * Used in struct thread_info
690 struct ftrace_ret_stack {
693 unsigned long long calltime;
694 unsigned long long subtime;
699 * Primary handler of a function return.
700 * It relays on ftrace_return_to_handler.
701 * Defined in entry_32/64.S
703 extern void return_to_handler(void);
706 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
707 unsigned long frame_pointer);
710 * Sometimes we don't want to trace a function with the function
711 * graph tracer but we want them to keep traced by the usual function
712 * tracer if the function graph tracer is not configured.
714 #define __notrace_funcgraph notrace
717 * We want to which function is an entrypoint of a hardirq.
718 * That will help us to put a signal on output.
720 #define __irq_entry __attribute__((__section__(".irqentry.text")))
722 /* Limits of hardirq entrypoints */
723 extern char __irqentry_text_start[];
724 extern char __irqentry_text_end[];
726 #define FTRACE_NOTRACE_DEPTH 65536
727 #define FTRACE_RETFUNC_DEPTH 50
728 #define FTRACE_RETSTACK_ALLOC_SIZE 32
729 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
730 trace_func_graph_ent_t entryfunc);
732 extern bool ftrace_graph_is_dead(void);
733 extern void ftrace_graph_stop(void);
735 /* The current handlers in use */
736 extern trace_func_graph_ret_t ftrace_graph_return;
737 extern trace_func_graph_ent_t ftrace_graph_entry;
739 extern void unregister_ftrace_graph(void);
741 extern void ftrace_graph_init_task(struct task_struct *t);
742 extern void ftrace_graph_exit_task(struct task_struct *t);
743 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
745 static inline int task_curr_ret_stack(struct task_struct *t)
747 return t->curr_ret_stack;
750 static inline void pause_graph_tracing(void)
752 atomic_inc(¤t->tracing_graph_pause);
755 static inline void unpause_graph_tracing(void)
757 atomic_dec(¤t->tracing_graph_pause);
759 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
761 #define __notrace_funcgraph
763 #define INIT_FTRACE_GRAPH
765 static inline void ftrace_graph_init_task(struct task_struct *t) { }
766 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
767 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
769 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
770 trace_func_graph_ent_t entryfunc)
774 static inline void unregister_ftrace_graph(void) { }
776 static inline int task_curr_ret_stack(struct task_struct *tsk)
781 static inline void pause_graph_tracing(void) { }
782 static inline void unpause_graph_tracing(void) { }
783 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
785 #ifdef CONFIG_TRACING
787 /* flags for current->trace */
789 TSK_TRACE_FL_TRACE_BIT = 0,
790 TSK_TRACE_FL_GRAPH_BIT = 1,
793 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
794 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
797 static inline void set_tsk_trace_trace(struct task_struct *tsk)
799 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
802 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
804 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
807 static inline int test_tsk_trace_trace(struct task_struct *tsk)
809 return tsk->trace & TSK_TRACE_FL_TRACE;
812 static inline void set_tsk_trace_graph(struct task_struct *tsk)
814 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
817 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
819 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
822 static inline int test_tsk_trace_graph(struct task_struct *tsk)
824 return tsk->trace & TSK_TRACE_FL_GRAPH;
827 enum ftrace_dump_mode;
829 extern enum ftrace_dump_mode ftrace_dump_on_oops;
831 extern void disable_trace_on_warning(void);
832 extern int __disable_trace_on_warning;
834 #ifdef CONFIG_PREEMPT
835 #define INIT_TRACE_RECURSION .trace_recursion = 0,
838 #else /* CONFIG_TRACING */
839 static inline void disable_trace_on_warning(void) { }
840 #endif /* CONFIG_TRACING */
842 #ifndef INIT_TRACE_RECURSION
843 #define INIT_TRACE_RECURSION
846 #ifdef CONFIG_FTRACE_SYSCALLS
848 unsigned long arch_syscall_addr(int nr);
850 #endif /* CONFIG_FTRACE_SYSCALLS */
852 #endif /* _LINUX_FTRACE_H */