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 !defined(CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST) || \
37 !ARCH_SUPPORTS_FTRACE_OPS
38 # define FTRACE_FORCE_LIST_FUNC 1
40 # define FTRACE_FORCE_LIST_FUNC 0
47 #ifdef CONFIG_FUNCTION_TRACER
49 extern int ftrace_enabled;
51 ftrace_enable_sysctl(struct ctl_table *table, int write,
52 void __user *buffer, size_t *lenp,
57 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
58 struct ftrace_ops *op, struct pt_regs *regs);
61 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
62 * set in the flags member.
64 * ENABLED - set/unset when ftrace_ops is registered/unregistered
65 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
66 * allocated ftrace_ops which need special care
67 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
68 * could be controled by following calls:
69 * ftrace_function_local_enable
70 * ftrace_function_local_disable
71 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
72 * and passed to the callback. If this flag is set, but the
73 * architecture does not support passing regs
74 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
75 * ftrace_ops will fail to register, unless the next flag
77 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
78 * handler can handle an arch that does not save regs
79 * (the handler tests if regs == NULL), then it can set
80 * this flag instead. It will not fail registering the ftrace_ops
81 * but, the regs field will be NULL if the arch does not support
82 * passing regs to the handler.
83 * Note, if this flag is set, the SAVE_REGS flag will automatically
84 * get set upon registering the ftrace_ops, if the arch supports it.
85 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
86 * that the call back has its own recursion protection. If it does
87 * not set this, then the ftrace infrastructure will add recursion
88 * protection for the caller.
89 * STUB - The ftrace_ops is just a place holder.
90 * INITIALIZED - The ftrace_ops has already been initialized (first use time
91 * register_ftrace_function() is called, it will initialized the ops)
92 * DELETED - The ops are being deleted, do not let them be registered again.
95 FTRACE_OPS_FL_ENABLED = 1 << 0,
96 FTRACE_OPS_FL_DYNAMIC = 1 << 1,
97 FTRACE_OPS_FL_CONTROL = 1 << 2,
98 FTRACE_OPS_FL_SAVE_REGS = 1 << 3,
99 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4,
100 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5,
101 FTRACE_OPS_FL_STUB = 1 << 6,
102 FTRACE_OPS_FL_INITIALIZED = 1 << 7,
103 FTRACE_OPS_FL_DELETED = 1 << 8,
107 * Note, ftrace_ops can be referenced outside of RCU protection.
108 * (Although, for perf, the control ops prevent that). If ftrace_ops is
109 * allocated and not part of kernel core data, the unregistering of it will
110 * perform a scheduling on all CPUs to make sure that there are no more users.
111 * Depending on the load of the system that may take a bit of time.
113 * Any private data added must also take care not to be freed and if private
114 * data is added to a ftrace_ops that is in core code, the user of the
115 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
119 struct ftrace_ops *next;
121 int __percpu *disabled;
123 #ifdef CONFIG_DYNAMIC_FTRACE
124 struct ftrace_hash *notrace_hash;
125 struct ftrace_hash *filter_hash;
126 struct mutex regex_lock;
130 extern int function_trace_stop;
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 * ftrace_stop - stop function tracer.
146 * A quick way to stop the function tracer. Note this an on off switch,
147 * it is not something that is recursive like preempt_disable.
148 * This does not disable the calling of mcount, it only stops the
149 * calling of functions from mcount.
151 static inline void ftrace_stop(void)
153 function_trace_stop = 1;
157 * ftrace_start - start the function tracer.
159 * This function is the inverse of ftrace_stop. This does not enable
160 * the function tracing if the function tracer is disabled. This only
161 * sets the function tracer flag to continue calling the functions
164 static inline void ftrace_start(void)
166 function_trace_stop = 0;
170 * The ftrace_ops must be a static and should also
171 * be read_mostly. These functions do modify read_mostly variables
172 * so use them sparely. Never free an ftrace_op or modify the
173 * next pointer after it has been registered. Even after unregistering
174 * it, the next pointer may still be used internally.
176 int register_ftrace_function(struct ftrace_ops *ops);
177 int unregister_ftrace_function(struct ftrace_ops *ops);
178 void clear_ftrace_function(void);
181 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
183 * This function enables tracing on current cpu by decreasing
184 * the per cpu control variable.
185 * It must be called with preemption disabled and only on ftrace_ops
186 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
187 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
189 static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
191 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
194 (*this_cpu_ptr(ops->disabled))--;
198 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
200 * This function enables tracing on current cpu by decreasing
201 * the per cpu control variable.
202 * It must be called with preemption disabled and only on ftrace_ops
203 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
204 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
206 static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
208 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
211 (*this_cpu_ptr(ops->disabled))++;
215 * ftrace_function_local_disabled - returns ftrace_ops disabled value
218 * This function returns value of ftrace_ops::disabled on current cpu.
219 * It must be called with preemption disabled and only on ftrace_ops
220 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
221 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
223 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
225 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
226 return *this_cpu_ptr(ops->disabled);
229 extern void ftrace_stub(unsigned long a0, unsigned long a1,
230 struct ftrace_ops *op, struct pt_regs *regs);
232 #else /* !CONFIG_FUNCTION_TRACER */
234 * (un)register_ftrace_function must be a macro since the ops parameter
235 * must not be evaluated.
237 #define register_ftrace_function(ops) ({ 0; })
238 #define unregister_ftrace_function(ops) ({ 0; })
239 static inline int ftrace_nr_registered_ops(void)
243 static inline void clear_ftrace_function(void) { }
244 static inline void ftrace_kill(void) { }
245 static inline void ftrace_stop(void) { }
246 static inline void ftrace_start(void) { }
247 #endif /* CONFIG_FUNCTION_TRACER */
249 #ifdef CONFIG_STACK_TRACER
250 extern int stack_tracer_enabled;
252 stack_trace_sysctl(struct ctl_table *table, int write,
253 void __user *buffer, size_t *lenp,
257 struct ftrace_func_command {
258 struct list_head list;
260 int (*func)(struct ftrace_hash *hash,
261 char *func, char *cmd,
262 char *params, int enable);
265 #ifdef CONFIG_DYNAMIC_FTRACE
267 int ftrace_arch_code_modify_prepare(void);
268 int ftrace_arch_code_modify_post_process(void);
270 void ftrace_bug(int err, unsigned long ip);
274 struct ftrace_probe_ops {
275 void (*func)(unsigned long ip,
276 unsigned long parent_ip,
278 int (*init)(struct ftrace_probe_ops *ops,
279 unsigned long ip, void **data);
280 void (*free)(struct ftrace_probe_ops *ops,
281 unsigned long ip, void **data);
282 int (*print)(struct seq_file *m,
284 struct ftrace_probe_ops *ops,
289 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
292 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
295 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
296 extern void unregister_ftrace_function_probe_all(char *glob);
298 extern int ftrace_text_reserved(const void *start, const void *end);
300 extern int ftrace_nr_registered_ops(void);
303 * The dyn_ftrace record's flags field is split into two parts.
304 * the first part which is '0-FTRACE_REF_MAX' is a counter of
305 * the number of callbacks that have registered the function that
306 * the dyn_ftrace descriptor represents.
308 * The second part is a mask:
309 * ENABLED - the function is being traced
310 * REGS - the record wants the function to save regs
311 * REGS_EN - the function is set up to save regs.
313 * When a new ftrace_ops is registered and wants a function to save
314 * pt_regs, the rec->flag REGS is set. When the function has been
315 * set up to save regs, the REG_EN flag is set. Once a function
316 * starts saving regs it will do so until all ftrace_ops are removed
317 * from tracing that function.
320 FTRACE_FL_ENABLED = (1UL << 29),
321 FTRACE_FL_REGS = (1UL << 30),
322 FTRACE_FL_REGS_EN = (1UL << 31)
325 #define FTRACE_REF_MAX_SHIFT 29
326 #define FTRACE_FL_BITS 3
327 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
328 #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
329 #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
332 unsigned long ip; /* address of mcount call-site */
334 struct dyn_arch_ftrace arch;
337 int ftrace_force_update(void);
338 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
339 int remove, int reset);
340 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
342 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
344 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
345 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
346 void ftrace_free_filter(struct ftrace_ops *ops);
348 int register_ftrace_command(struct ftrace_func_command *cmd);
349 int unregister_ftrace_command(struct ftrace_func_command *cmd);
352 FTRACE_UPDATE_CALLS = (1 << 0),
353 FTRACE_DISABLE_CALLS = (1 << 1),
354 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
355 FTRACE_START_FUNC_RET = (1 << 3),
356 FTRACE_STOP_FUNC_RET = (1 << 4),
360 * The FTRACE_UPDATE_* enum is used to pass information back
361 * from the ftrace_update_record() and ftrace_test_record()
362 * functions. These are called by the code update routines
363 * to find out what is to be done for a given function.
365 * IGNORE - The function is already what we want it to be
366 * MAKE_CALL - Start tracing the function
367 * MODIFY_CALL - Stop saving regs for the function
368 * MAKE_NOP - Stop tracing the function
371 FTRACE_UPDATE_IGNORE,
372 FTRACE_UPDATE_MAKE_CALL,
373 FTRACE_UPDATE_MODIFY_CALL,
374 FTRACE_UPDATE_MAKE_NOP,
378 FTRACE_ITER_FILTER = (1 << 0),
379 FTRACE_ITER_NOTRACE = (1 << 1),
380 FTRACE_ITER_PRINTALL = (1 << 2),
381 FTRACE_ITER_DO_HASH = (1 << 3),
382 FTRACE_ITER_HASH = (1 << 4),
383 FTRACE_ITER_ENABLED = (1 << 5),
386 void arch_ftrace_update_code(int command);
388 struct ftrace_rec_iter;
390 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
391 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
392 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
394 #define for_ftrace_rec_iter(iter) \
395 for (iter = ftrace_rec_iter_start(); \
397 iter = ftrace_rec_iter_next(iter))
400 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
401 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
402 void ftrace_run_stop_machine(int command);
403 unsigned long ftrace_location(unsigned long ip);
404 unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
405 unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
407 extern ftrace_func_t ftrace_trace_function;
409 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
410 struct inode *inode, struct file *file);
411 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
412 size_t cnt, loff_t *ppos);
413 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
414 size_t cnt, loff_t *ppos);
415 int ftrace_regex_release(struct inode *inode, struct file *file);
418 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
420 /* defined in arch */
421 extern int ftrace_ip_converted(unsigned long ip);
422 extern int ftrace_dyn_arch_init(void);
423 extern void ftrace_replace_code(int enable);
424 extern int ftrace_update_ftrace_func(ftrace_func_t func);
425 extern void ftrace_caller(void);
426 extern void ftrace_regs_caller(void);
427 extern void ftrace_call(void);
428 extern void ftrace_regs_call(void);
429 extern void mcount_call(void);
431 void ftrace_modify_all_code(int command);
434 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
437 #ifndef FTRACE_REGS_ADDR
438 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
439 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
441 # define FTRACE_REGS_ADDR FTRACE_ADDR
445 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
446 extern void ftrace_graph_caller(void);
447 extern int ftrace_enable_ftrace_graph_caller(void);
448 extern int ftrace_disable_ftrace_graph_caller(void);
450 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
451 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
455 * ftrace_make_nop - convert code into nop
456 * @mod: module structure if called by module load initialization
457 * @rec: the mcount call site record
458 * @addr: the address that the call site should be calling
460 * This is a very sensitive operation and great care needs
461 * to be taken by the arch. The operation should carefully
462 * read the location, check to see if what is read is indeed
463 * what we expect it to be, and then on success of the compare,
464 * it should write to the location.
466 * The code segment at @rec->ip should be a caller to @addr
470 * -EFAULT on error reading the location
471 * -EINVAL on a failed compare of the contents
472 * -EPERM on error writing to the location
473 * Any other value will be considered a failure.
475 extern int ftrace_make_nop(struct module *mod,
476 struct dyn_ftrace *rec, unsigned long addr);
479 * ftrace_make_call - convert a nop call site into a call to addr
480 * @rec: the mcount call site record
481 * @addr: the address that the call site should call
483 * This is a very sensitive operation and great care needs
484 * to be taken by the arch. The operation should carefully
485 * read the location, check to see if what is read is indeed
486 * what we expect it to be, and then on success of the compare,
487 * it should write to the location.
489 * The code segment at @rec->ip should be a nop
493 * -EFAULT on error reading the location
494 * -EINVAL on a failed compare of the contents
495 * -EPERM on error writing to the location
496 * Any other value will be considered a failure.
498 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
500 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
502 * ftrace_modify_call - convert from one addr to another (no nop)
503 * @rec: the mcount call site record
504 * @old_addr: the address expected to be currently called to
505 * @addr: the address to change to
507 * This is a very sensitive operation and great care needs
508 * to be taken by the arch. The operation should carefully
509 * read the location, check to see if what is read is indeed
510 * what we expect it to be, and then on success of the compare,
511 * it should write to the location.
513 * The code segment at @rec->ip should be a caller to @old_addr
517 * -EFAULT on error reading the location
518 * -EINVAL on a failed compare of the contents
519 * -EPERM on error writing to the location
520 * Any other value will be considered a failure.
522 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
525 /* Should never be called */
526 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
533 /* May be defined in arch */
534 extern int ftrace_arch_read_dyn_info(char *buf, int size);
536 extern int skip_trace(unsigned long ip);
537 extern void ftrace_module_init(struct module *mod);
539 extern void ftrace_disable_daemon(void);
540 extern void ftrace_enable_daemon(void);
541 #else /* CONFIG_DYNAMIC_FTRACE */
542 static inline int skip_trace(unsigned long ip) { return 0; }
543 static inline int ftrace_force_update(void) { return 0; }
544 static inline void ftrace_disable_daemon(void) { }
545 static inline void ftrace_enable_daemon(void) { }
546 static inline void ftrace_release_mod(struct module *mod) {}
547 static inline void ftrace_module_init(struct module *mod) {}
548 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
552 static inline __init int unregister_ftrace_command(char *cmd_name)
556 static inline int ftrace_text_reserved(const void *start, const void *end)
560 static inline unsigned long ftrace_location(unsigned long ip)
566 * Again users of functions that have ftrace_ops may not
567 * have them defined when ftrace is not enabled, but these
568 * functions may still be called. Use a macro instead of inline.
570 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
571 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
572 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
573 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
574 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
575 #define ftrace_free_filter(ops) do { } while (0)
577 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
578 size_t cnt, loff_t *ppos) { return -ENODEV; }
579 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
580 size_t cnt, loff_t *ppos) { return -ENODEV; }
582 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
583 #endif /* CONFIG_DYNAMIC_FTRACE */
585 /* totally disable ftrace - can not re-enable after this */
586 void ftrace_kill(void);
588 static inline void tracer_disable(void)
590 #ifdef CONFIG_FUNCTION_TRACER
596 * Ftrace disable/restore without lock. Some synchronization mechanism
597 * must be used to prevent ftrace_enabled to be changed between
600 static inline int __ftrace_enabled_save(void)
602 #ifdef CONFIG_FUNCTION_TRACER
603 int saved_ftrace_enabled = ftrace_enabled;
605 return saved_ftrace_enabled;
611 static inline void __ftrace_enabled_restore(int enabled)
613 #ifdef CONFIG_FUNCTION_TRACER
614 ftrace_enabled = enabled;
618 /* All archs should have this, but we define it for consistency */
619 #ifndef ftrace_return_address0
620 # define ftrace_return_address0 __builtin_return_address(0)
623 /* Archs may use other ways for ADDR1 and beyond */
624 #ifndef ftrace_return_address
625 # ifdef CONFIG_FRAME_POINTER
626 # define ftrace_return_address(n) __builtin_return_address(n)
628 # define ftrace_return_address(n) 0UL
632 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
633 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
634 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
635 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
636 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
637 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
638 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
640 #ifdef CONFIG_IRQSOFF_TRACER
641 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
642 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
644 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
645 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
648 #ifdef CONFIG_PREEMPT_TRACER
649 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
650 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
653 * Use defines instead of static inlines because some arches will make code out
654 * of the CALLER_ADDR, when we really want these to be a real nop.
656 # define trace_preempt_on(a0, a1) do { } while (0)
657 # define trace_preempt_off(a0, a1) do { } while (0)
660 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
661 extern void ftrace_init(void);
663 static inline void ftrace_init(void) { }
667 * Structure that defines an entry function trace.
669 struct ftrace_graph_ent {
670 unsigned long func; /* Current function */
675 * Structure that defines a return function trace.
677 struct ftrace_graph_ret {
678 unsigned long func; /* Current function */
679 unsigned long long calltime;
680 unsigned long long rettime;
681 /* Number of functions that overran the depth limit for current task */
682 unsigned long overrun;
686 /* Type of the callback handlers for tracing function graph*/
687 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
688 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
690 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
693 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
696 * Stack of return addresses for functions
698 * Used in struct thread_info
700 struct ftrace_ret_stack {
703 unsigned long long calltime;
704 unsigned long long subtime;
709 * Primary handler of a function return.
710 * It relays on ftrace_return_to_handler.
711 * Defined in entry_32/64.S
713 extern void return_to_handler(void);
716 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
717 unsigned long frame_pointer);
720 * Sometimes we don't want to trace a function with the function
721 * graph tracer but we want them to keep traced by the usual function
722 * tracer if the function graph tracer is not configured.
724 #define __notrace_funcgraph notrace
727 * We want to which function is an entrypoint of a hardirq.
728 * That will help us to put a signal on output.
730 #define __irq_entry __attribute__((__section__(".irqentry.text")))
732 /* Limits of hardirq entrypoints */
733 extern char __irqentry_text_start[];
734 extern char __irqentry_text_end[];
736 #define FTRACE_NOTRACE_DEPTH 65536
737 #define FTRACE_RETFUNC_DEPTH 50
738 #define FTRACE_RETSTACK_ALLOC_SIZE 32
739 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
740 trace_func_graph_ent_t entryfunc);
742 extern void ftrace_graph_stop(void);
744 /* The current handlers in use */
745 extern trace_func_graph_ret_t ftrace_graph_return;
746 extern trace_func_graph_ent_t ftrace_graph_entry;
748 extern void unregister_ftrace_graph(void);
750 extern void ftrace_graph_init_task(struct task_struct *t);
751 extern void ftrace_graph_exit_task(struct task_struct *t);
752 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
754 static inline int task_curr_ret_stack(struct task_struct *t)
756 return t->curr_ret_stack;
759 static inline void pause_graph_tracing(void)
761 atomic_inc(¤t->tracing_graph_pause);
764 static inline void unpause_graph_tracing(void)
766 atomic_dec(¤t->tracing_graph_pause);
768 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
770 #define __notrace_funcgraph
772 #define INIT_FTRACE_GRAPH
774 static inline void ftrace_graph_init_task(struct task_struct *t) { }
775 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
776 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
778 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
779 trace_func_graph_ent_t entryfunc)
783 static inline void unregister_ftrace_graph(void) { }
785 static inline int task_curr_ret_stack(struct task_struct *tsk)
790 static inline void pause_graph_tracing(void) { }
791 static inline void unpause_graph_tracing(void) { }
792 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
794 #ifdef CONFIG_TRACING
796 /* flags for current->trace */
798 TSK_TRACE_FL_TRACE_BIT = 0,
799 TSK_TRACE_FL_GRAPH_BIT = 1,
802 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
803 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
806 static inline void set_tsk_trace_trace(struct task_struct *tsk)
808 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
811 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
813 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
816 static inline int test_tsk_trace_trace(struct task_struct *tsk)
818 return tsk->trace & TSK_TRACE_FL_TRACE;
821 static inline void set_tsk_trace_graph(struct task_struct *tsk)
823 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
826 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
828 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
831 static inline int test_tsk_trace_graph(struct task_struct *tsk)
833 return tsk->trace & TSK_TRACE_FL_GRAPH;
836 enum ftrace_dump_mode;
838 extern enum ftrace_dump_mode ftrace_dump_on_oops;
840 extern void disable_trace_on_warning(void);
841 extern int __disable_trace_on_warning;
843 #ifdef CONFIG_PREEMPT
844 #define INIT_TRACE_RECURSION .trace_recursion = 0,
847 #else /* CONFIG_TRACING */
848 static inline void disable_trace_on_warning(void) { }
849 #endif /* CONFIG_TRACING */
851 #ifndef INIT_TRACE_RECURSION
852 #define INIT_TRACE_RECURSION
855 #ifdef CONFIG_FTRACE_SYSCALLS
857 unsigned long arch_syscall_addr(int nr);
859 #endif /* CONFIG_FTRACE_SYSCALLS */
861 #endif /* _LINUX_FTRACE_H */