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);
59 ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops);
62 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
63 * set in the flags member.
65 * ENABLED - set/unset when ftrace_ops is registered/unregistered
66 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
67 * allocated ftrace_ops which need special care
68 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
69 * could be controled by following calls:
70 * ftrace_function_local_enable
71 * ftrace_function_local_disable
72 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
73 * and passed to the callback. If this flag is set, but the
74 * architecture does not support passing regs
75 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
76 * ftrace_ops will fail to register, unless the next flag
78 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
79 * handler can handle an arch that does not save regs
80 * (the handler tests if regs == NULL), then it can set
81 * this flag instead. It will not fail registering the ftrace_ops
82 * but, the regs field will be NULL if the arch does not support
83 * passing regs to the handler.
84 * Note, if this flag is set, the SAVE_REGS flag will automatically
85 * get set upon registering the ftrace_ops, if the arch supports it.
86 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
87 * that the call back has its own recursion protection. If it does
88 * not set this, then the ftrace infrastructure will add recursion
89 * protection for the caller.
90 * STUB - The ftrace_ops is just a place holder.
91 * INITIALIZED - The ftrace_ops has already been initialized (first use time
92 * register_ftrace_function() is called, it will initialized the ops)
93 * DELETED - The ops are being deleted, do not let them be registered again.
94 * ADDING - The ops is in the process of being added.
95 * REMOVING - The ops is in the process of being removed.
96 * MODIFYING - The ops is in the process of changing its filter functions.
99 FTRACE_OPS_FL_ENABLED = 1 << 0,
100 FTRACE_OPS_FL_DYNAMIC = 1 << 1,
101 FTRACE_OPS_FL_CONTROL = 1 << 2,
102 FTRACE_OPS_FL_SAVE_REGS = 1 << 3,
103 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4,
104 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5,
105 FTRACE_OPS_FL_STUB = 1 << 6,
106 FTRACE_OPS_FL_INITIALIZED = 1 << 7,
107 FTRACE_OPS_FL_DELETED = 1 << 8,
108 FTRACE_OPS_FL_ADDING = 1 << 9,
109 FTRACE_OPS_FL_REMOVING = 1 << 10,
110 FTRACE_OPS_FL_MODIFYING = 1 << 11,
113 #ifdef CONFIG_DYNAMIC_FTRACE
114 /* The hash used to know what functions callbacks trace */
115 struct ftrace_ops_hash {
116 struct ftrace_hash *notrace_hash;
117 struct ftrace_hash *filter_hash;
118 struct mutex regex_lock;
123 * Note, ftrace_ops can be referenced outside of RCU protection.
124 * (Although, for perf, the control ops prevent that). If ftrace_ops is
125 * allocated and not part of kernel core data, the unregistering of it will
126 * perform a scheduling on all CPUs to make sure that there are no more users.
127 * Depending on the load of the system that may take a bit of time.
129 * Any private data added must also take care not to be freed and if private
130 * data is added to a ftrace_ops that is in core code, the user of the
131 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
135 struct ftrace_ops *next;
138 int __percpu *disabled;
139 #ifdef CONFIG_DYNAMIC_FTRACE
141 struct ftrace_ops_hash local_hash;
142 struct ftrace_ops_hash *func_hash;
143 struct ftrace_ops_hash old_hash;
144 unsigned long trampoline;
149 * Type of the current tracing.
151 enum ftrace_tracing_type_t {
152 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
153 FTRACE_TYPE_RETURN, /* Hook the return of the function */
156 /* Current tracing type, default is FTRACE_TYPE_ENTER */
157 extern enum ftrace_tracing_type_t ftrace_tracing_type;
160 * The ftrace_ops must be a static and should also
161 * be read_mostly. These functions do modify read_mostly variables
162 * so use them sparely. Never free an ftrace_op or modify the
163 * next pointer after it has been registered. Even after unregistering
164 * it, the next pointer may still be used internally.
166 int register_ftrace_function(struct ftrace_ops *ops);
167 int unregister_ftrace_function(struct ftrace_ops *ops);
168 void clear_ftrace_function(void);
171 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
173 * This function enables tracing on current cpu by decreasing
174 * the per cpu control variable.
175 * It must be called with preemption disabled and only on ftrace_ops
176 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
177 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
179 static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
181 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
184 (*this_cpu_ptr(ops->disabled))--;
188 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
190 * This function enables tracing on current cpu by decreasing
191 * the per cpu control variable.
192 * It must be called with preemption disabled and only on ftrace_ops
193 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
194 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
196 static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
198 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
201 (*this_cpu_ptr(ops->disabled))++;
205 * ftrace_function_local_disabled - returns ftrace_ops disabled value
208 * This function returns value of ftrace_ops::disabled on current cpu.
209 * It must be called with preemption disabled and only on ftrace_ops
210 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
211 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
213 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
215 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
216 return *this_cpu_ptr(ops->disabled);
219 extern void ftrace_stub(unsigned long a0, unsigned long a1,
220 struct ftrace_ops *op, struct pt_regs *regs);
222 #else /* !CONFIG_FUNCTION_TRACER */
224 * (un)register_ftrace_function must be a macro since the ops parameter
225 * must not be evaluated.
227 #define register_ftrace_function(ops) ({ 0; })
228 #define unregister_ftrace_function(ops) ({ 0; })
229 static inline int ftrace_nr_registered_ops(void)
233 static inline void clear_ftrace_function(void) { }
234 static inline void ftrace_kill(void) { }
235 #endif /* CONFIG_FUNCTION_TRACER */
237 #ifdef CONFIG_STACK_TRACER
238 extern int stack_tracer_enabled;
240 stack_trace_sysctl(struct ctl_table *table, int write,
241 void __user *buffer, size_t *lenp,
245 struct ftrace_func_command {
246 struct list_head list;
248 int (*func)(struct ftrace_hash *hash,
249 char *func, char *cmd,
250 char *params, int enable);
253 #ifdef CONFIG_DYNAMIC_FTRACE
255 int ftrace_arch_code_modify_prepare(void);
256 int ftrace_arch_code_modify_post_process(void);
258 void ftrace_bug(int err, unsigned long ip);
262 struct ftrace_probe_ops {
263 void (*func)(unsigned long ip,
264 unsigned long parent_ip,
266 int (*init)(struct ftrace_probe_ops *ops,
267 unsigned long ip, void **data);
268 void (*free)(struct ftrace_probe_ops *ops,
269 unsigned long ip, void **data);
270 int (*print)(struct seq_file *m,
272 struct ftrace_probe_ops *ops,
277 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
280 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
283 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
284 extern void unregister_ftrace_function_probe_all(char *glob);
286 extern int ftrace_text_reserved(const void *start, const void *end);
288 extern int ftrace_nr_registered_ops(void);
291 * The dyn_ftrace record's flags field is split into two parts.
292 * the first part which is '0-FTRACE_REF_MAX' is a counter of
293 * the number of callbacks that have registered the function that
294 * the dyn_ftrace descriptor represents.
296 * The second part is a mask:
297 * ENABLED - the function is being traced
298 * REGS - the record wants the function to save regs
299 * REGS_EN - the function is set up to save regs.
301 * When a new ftrace_ops is registered and wants a function to save
302 * pt_regs, the rec->flag REGS is set. When the function has been
303 * set up to save regs, the REG_EN flag is set. Once a function
304 * starts saving regs it will do so until all ftrace_ops are removed
305 * from tracing that function.
308 FTRACE_FL_ENABLED = (1UL << 31),
309 FTRACE_FL_REGS = (1UL << 30),
310 FTRACE_FL_REGS_EN = (1UL << 29),
311 FTRACE_FL_TRAMP = (1UL << 28),
312 FTRACE_FL_TRAMP_EN = (1UL << 27),
315 #define FTRACE_REF_MAX_SHIFT 27
316 #define FTRACE_FL_BITS 5
317 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
318 #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
319 #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
321 #define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK)
324 unsigned long ip; /* address of mcount call-site */
326 struct dyn_arch_ftrace arch;
329 int ftrace_force_update(void);
330 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
331 int remove, int reset);
332 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
334 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
336 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
337 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
338 void ftrace_free_filter(struct ftrace_ops *ops);
340 int register_ftrace_command(struct ftrace_func_command *cmd);
341 int unregister_ftrace_command(struct ftrace_func_command *cmd);
344 FTRACE_UPDATE_CALLS = (1 << 0),
345 FTRACE_DISABLE_CALLS = (1 << 1),
346 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
347 FTRACE_START_FUNC_RET = (1 << 3),
348 FTRACE_STOP_FUNC_RET = (1 << 4),
352 * The FTRACE_UPDATE_* enum is used to pass information back
353 * from the ftrace_update_record() and ftrace_test_record()
354 * functions. These are called by the code update routines
355 * to find out what is to be done for a given function.
357 * IGNORE - The function is already what we want it to be
358 * MAKE_CALL - Start tracing the function
359 * MODIFY_CALL - Stop saving regs for the function
360 * MAKE_NOP - Stop tracing the function
363 FTRACE_UPDATE_IGNORE,
364 FTRACE_UPDATE_MAKE_CALL,
365 FTRACE_UPDATE_MODIFY_CALL,
366 FTRACE_UPDATE_MAKE_NOP,
370 FTRACE_ITER_FILTER = (1 << 0),
371 FTRACE_ITER_NOTRACE = (1 << 1),
372 FTRACE_ITER_PRINTALL = (1 << 2),
373 FTRACE_ITER_DO_HASH = (1 << 3),
374 FTRACE_ITER_HASH = (1 << 4),
375 FTRACE_ITER_ENABLED = (1 << 5),
378 void arch_ftrace_update_code(int command);
380 struct ftrace_rec_iter;
382 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
383 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
384 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
386 #define for_ftrace_rec_iter(iter) \
387 for (iter = ftrace_rec_iter_start(); \
389 iter = ftrace_rec_iter_next(iter))
392 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
393 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
394 void ftrace_run_stop_machine(int command);
395 unsigned long ftrace_location(unsigned long ip);
396 unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
397 unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
399 extern ftrace_func_t ftrace_trace_function;
401 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
402 struct inode *inode, struct file *file);
403 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
404 size_t cnt, loff_t *ppos);
405 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
406 size_t cnt, loff_t *ppos);
407 int ftrace_regex_release(struct inode *inode, struct file *file);
410 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
412 /* defined in arch */
413 extern int ftrace_ip_converted(unsigned long ip);
414 extern int ftrace_dyn_arch_init(void);
415 extern void ftrace_replace_code(int enable);
416 extern int ftrace_update_ftrace_func(ftrace_func_t func);
417 extern void ftrace_caller(void);
418 extern void ftrace_regs_caller(void);
419 extern void ftrace_call(void);
420 extern void ftrace_regs_call(void);
421 extern void mcount_call(void);
423 void ftrace_modify_all_code(int command);
426 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
429 #ifndef FTRACE_GRAPH_ADDR
430 #define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
433 #ifndef FTRACE_REGS_ADDR
434 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
435 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
437 # define FTRACE_REGS_ADDR FTRACE_ADDR
442 * If an arch would like functions that are only traced
443 * by the function graph tracer to jump directly to its own
444 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
445 * to be that address to jump to.
447 #ifndef FTRACE_GRAPH_TRAMP_ADDR
448 #define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
451 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
452 extern void ftrace_graph_caller(void);
453 extern int ftrace_enable_ftrace_graph_caller(void);
454 extern int ftrace_disable_ftrace_graph_caller(void);
456 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
457 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
461 * ftrace_make_nop - convert code into nop
462 * @mod: module structure if called by module load initialization
463 * @rec: the mcount call site record
464 * @addr: the address that the call site should be calling
466 * This is a very sensitive operation and great care needs
467 * to be taken by the arch. The operation should carefully
468 * read the location, check to see if what is read is indeed
469 * what we expect it to be, and then on success of the compare,
470 * it should write to the location.
472 * The code segment at @rec->ip should be a caller to @addr
476 * -EFAULT on error reading the location
477 * -EINVAL on a failed compare of the contents
478 * -EPERM on error writing to the location
479 * Any other value will be considered a failure.
481 extern int ftrace_make_nop(struct module *mod,
482 struct dyn_ftrace *rec, unsigned long addr);
485 * ftrace_make_call - convert a nop call site into a call to addr
486 * @rec: the mcount call site record
487 * @addr: the address that the call site should call
489 * This is a very sensitive operation and great care needs
490 * to be taken by the arch. The operation should carefully
491 * read the location, check to see if what is read is indeed
492 * what we expect it to be, and then on success of the compare,
493 * it should write to the location.
495 * The code segment at @rec->ip should be a nop
499 * -EFAULT on error reading the location
500 * -EINVAL on a failed compare of the contents
501 * -EPERM on error writing to the location
502 * Any other value will be considered a failure.
504 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
506 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
508 * ftrace_modify_call - convert from one addr to another (no nop)
509 * @rec: the mcount call site record
510 * @old_addr: the address expected to be currently called to
511 * @addr: the address to change to
513 * This is a very sensitive operation and great care needs
514 * to be taken by the arch. The operation should carefully
515 * read the location, check to see if what is read is indeed
516 * what we expect it to be, and then on success of the compare,
517 * it should write to the location.
519 * The code segment at @rec->ip should be a caller to @old_addr
523 * -EFAULT on error reading the location
524 * -EINVAL on a failed compare of the contents
525 * -EPERM on error writing to the location
526 * Any other value will be considered a failure.
528 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
531 /* Should never be called */
532 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
539 /* May be defined in arch */
540 extern int ftrace_arch_read_dyn_info(char *buf, int size);
542 extern int skip_trace(unsigned long ip);
543 extern void ftrace_module_init(struct module *mod);
545 extern void ftrace_disable_daemon(void);
546 extern void ftrace_enable_daemon(void);
547 #else /* CONFIG_DYNAMIC_FTRACE */
548 static inline int skip_trace(unsigned long ip) { return 0; }
549 static inline int ftrace_force_update(void) { return 0; }
550 static inline void ftrace_disable_daemon(void) { }
551 static inline void ftrace_enable_daemon(void) { }
552 static inline void ftrace_release_mod(struct module *mod) {}
553 static inline void ftrace_module_init(struct module *mod) {}
554 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
558 static inline __init int unregister_ftrace_command(char *cmd_name)
562 static inline int ftrace_text_reserved(const void *start, const void *end)
566 static inline unsigned long ftrace_location(unsigned long ip)
572 * Again users of functions that have ftrace_ops may not
573 * have them defined when ftrace is not enabled, but these
574 * functions may still be called. Use a macro instead of inline.
576 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
577 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
578 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
579 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
580 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
581 #define ftrace_free_filter(ops) do { } while (0)
583 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
584 size_t cnt, loff_t *ppos) { return -ENODEV; }
585 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
586 size_t cnt, loff_t *ppos) { return -ENODEV; }
588 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
589 #endif /* CONFIG_DYNAMIC_FTRACE */
591 /* totally disable ftrace - can not re-enable after this */
592 void ftrace_kill(void);
594 static inline void tracer_disable(void)
596 #ifdef CONFIG_FUNCTION_TRACER
602 * Ftrace disable/restore without lock. Some synchronization mechanism
603 * must be used to prevent ftrace_enabled to be changed between
606 static inline int __ftrace_enabled_save(void)
608 #ifdef CONFIG_FUNCTION_TRACER
609 int saved_ftrace_enabled = ftrace_enabled;
611 return saved_ftrace_enabled;
617 static inline void __ftrace_enabled_restore(int enabled)
619 #ifdef CONFIG_FUNCTION_TRACER
620 ftrace_enabled = enabled;
624 /* All archs should have this, but we define it for consistency */
625 #ifndef ftrace_return_address0
626 # define ftrace_return_address0 __builtin_return_address(0)
629 /* Archs may use other ways for ADDR1 and beyond */
630 #ifndef ftrace_return_address
631 # ifdef CONFIG_FRAME_POINTER
632 # define ftrace_return_address(n) __builtin_return_address(n)
634 # define ftrace_return_address(n) 0UL
638 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
639 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
640 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
641 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
642 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
643 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
644 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
646 #ifdef CONFIG_IRQSOFF_TRACER
647 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
648 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
650 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
651 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
654 #ifdef CONFIG_PREEMPT_TRACER
655 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
656 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
659 * Use defines instead of static inlines because some arches will make code out
660 * of the CALLER_ADDR, when we really want these to be a real nop.
662 # define trace_preempt_on(a0, a1) do { } while (0)
663 # define trace_preempt_off(a0, a1) do { } while (0)
666 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
667 extern void ftrace_init(void);
669 static inline void ftrace_init(void) { }
673 * Structure that defines an entry function trace.
675 struct ftrace_graph_ent {
676 unsigned long func; /* Current function */
681 * Structure that defines a return function trace.
683 struct ftrace_graph_ret {
684 unsigned long func; /* Current function */
685 unsigned long long calltime;
686 unsigned long long rettime;
687 /* Number of functions that overran the depth limit for current task */
688 unsigned long overrun;
692 /* Type of the callback handlers for tracing function graph*/
693 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
694 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
696 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
699 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
702 * Stack of return addresses for functions
704 * Used in struct thread_info
706 struct ftrace_ret_stack {
709 unsigned long long calltime;
710 unsigned long long subtime;
715 * Primary handler of a function return.
716 * It relays on ftrace_return_to_handler.
717 * Defined in entry_32/64.S
719 extern void return_to_handler(void);
722 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
723 unsigned long frame_pointer);
726 * Sometimes we don't want to trace a function with the function
727 * graph tracer but we want them to keep traced by the usual function
728 * tracer if the function graph tracer is not configured.
730 #define __notrace_funcgraph notrace
733 * We want to which function is an entrypoint of a hardirq.
734 * That will help us to put a signal on output.
736 #define __irq_entry __attribute__((__section__(".irqentry.text")))
738 /* Limits of hardirq entrypoints */
739 extern char __irqentry_text_start[];
740 extern char __irqentry_text_end[];
742 #define FTRACE_NOTRACE_DEPTH 65536
743 #define FTRACE_RETFUNC_DEPTH 50
744 #define FTRACE_RETSTACK_ALLOC_SIZE 32
745 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
746 trace_func_graph_ent_t entryfunc);
748 extern bool ftrace_graph_is_dead(void);
749 extern void ftrace_graph_stop(void);
751 /* The current handlers in use */
752 extern trace_func_graph_ret_t ftrace_graph_return;
753 extern trace_func_graph_ent_t ftrace_graph_entry;
755 extern void unregister_ftrace_graph(void);
757 extern void ftrace_graph_init_task(struct task_struct *t);
758 extern void ftrace_graph_exit_task(struct task_struct *t);
759 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
761 static inline int task_curr_ret_stack(struct task_struct *t)
763 return t->curr_ret_stack;
766 static inline void pause_graph_tracing(void)
768 atomic_inc(¤t->tracing_graph_pause);
771 static inline void unpause_graph_tracing(void)
773 atomic_dec(¤t->tracing_graph_pause);
775 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
777 #define __notrace_funcgraph
779 #define INIT_FTRACE_GRAPH
781 static inline void ftrace_graph_init_task(struct task_struct *t) { }
782 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
783 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
785 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
786 trace_func_graph_ent_t entryfunc)
790 static inline void unregister_ftrace_graph(void) { }
792 static inline int task_curr_ret_stack(struct task_struct *tsk)
797 static inline void pause_graph_tracing(void) { }
798 static inline void unpause_graph_tracing(void) { }
799 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
801 #ifdef CONFIG_TRACING
803 /* flags for current->trace */
805 TSK_TRACE_FL_TRACE_BIT = 0,
806 TSK_TRACE_FL_GRAPH_BIT = 1,
809 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
810 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
813 static inline void set_tsk_trace_trace(struct task_struct *tsk)
815 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
818 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
820 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
823 static inline int test_tsk_trace_trace(struct task_struct *tsk)
825 return tsk->trace & TSK_TRACE_FL_TRACE;
828 static inline void set_tsk_trace_graph(struct task_struct *tsk)
830 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
833 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
835 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
838 static inline int test_tsk_trace_graph(struct task_struct *tsk)
840 return tsk->trace & TSK_TRACE_FL_GRAPH;
843 enum ftrace_dump_mode;
845 extern enum ftrace_dump_mode ftrace_dump_on_oops;
847 extern void disable_trace_on_warning(void);
848 extern int __disable_trace_on_warning;
850 #ifdef CONFIG_PREEMPT
851 #define INIT_TRACE_RECURSION .trace_recursion = 0,
854 #else /* CONFIG_TRACING */
855 static inline void disable_trace_on_warning(void) { }
856 #endif /* CONFIG_TRACING */
858 #ifndef INIT_TRACE_RECURSION
859 #define INIT_TRACE_RECURSION
862 #ifdef CONFIG_FTRACE_SYSCALLS
864 unsigned long arch_syscall_addr(int nr);
866 #endif /* CONFIG_FTRACE_SYSCALLS */
868 #endif /* _LINUX_FTRACE_H */