1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Ftrace header. For implementation details beyond the random comments
4 * scattered below, see: Documentation/trace/ftrace-design.txt
7 #ifndef _LINUX_FTRACE_H
8 #define _LINUX_FTRACE_H
10 #include <linux/trace_clock.h>
11 #include <linux/kallsyms.h>
12 #include <linux/linkage.h>
13 #include <linux/bitops.h>
14 #include <linux/ptrace.h>
15 #include <linux/ktime.h>
16 #include <linux/sched.h>
17 #include <linux/types.h>
18 #include <linux/init.h>
21 #include <asm/ftrace.h>
24 * If the arch supports passing the variable contents of
25 * function_trace_op as the third parameter back from the
26 * mcount call, then the arch should define this as 1.
28 #ifndef ARCH_SUPPORTS_FTRACE_OPS
29 #define ARCH_SUPPORTS_FTRACE_OPS 0
33 * If the arch's mcount caller does not support all of ftrace's
34 * features, then it must call an indirect function that
35 * does. Or at least does enough to prevent any unwelcomed side effects.
37 #if !ARCH_SUPPORTS_FTRACE_OPS
38 # define FTRACE_FORCE_LIST_FUNC 1
40 # define FTRACE_FORCE_LIST_FUNC 0
43 /* Main tracing buffer and events set up */
45 void trace_init(void);
46 void early_trace_init(void);
48 static inline void trace_init(void) { }
49 static inline void early_trace_init(void) { }
55 #ifdef CONFIG_FUNCTION_TRACER
57 extern int ftrace_enabled
;
59 ftrace_enable_sysctl(struct ctl_table
*table
, int write
,
60 void __user
*buffer
, size_t *lenp
,
65 typedef void (*ftrace_func_t
)(unsigned long ip
, unsigned long parent_ip
,
66 struct ftrace_ops
*op
, struct pt_regs
*regs
);
68 ftrace_func_t
ftrace_ops_get_func(struct ftrace_ops
*ops
);
71 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
72 * set in the flags member.
73 * CONTROL, SAVE_REGS, SAVE_REGS_IF_SUPPORTED, RECURSION_SAFE, STUB and
74 * IPMODIFY are a kind of attribute flags which can be set only before
75 * registering the ftrace_ops, and can not be modified while registered.
76 * Changing those attribute flags after registering ftrace_ops will
77 * cause unexpected results.
79 * ENABLED - set/unset when ftrace_ops is registered/unregistered
80 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
81 * allocated ftrace_ops which need special care
82 * PER_CPU - set manualy by ftrace_ops user to denote the ftrace_ops
83 * could be controlled by following calls:
84 * ftrace_function_local_enable
85 * ftrace_function_local_disable
86 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
87 * and passed to the callback. If this flag is set, but the
88 * architecture does not support passing regs
89 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
90 * ftrace_ops will fail to register, unless the next flag
92 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
93 * handler can handle an arch that does not save regs
94 * (the handler tests if regs == NULL), then it can set
95 * this flag instead. It will not fail registering the ftrace_ops
96 * but, the regs field will be NULL if the arch does not support
97 * passing regs to the handler.
98 * Note, if this flag is set, the SAVE_REGS flag will automatically
99 * get set upon registering the ftrace_ops, if the arch supports it.
100 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
101 * that the call back has its own recursion protection. If it does
102 * not set this, then the ftrace infrastructure will add recursion
103 * protection for the caller.
104 * STUB - The ftrace_ops is just a place holder.
105 * INITIALIZED - The ftrace_ops has already been initialized (first use time
106 * register_ftrace_function() is called, it will initialized the ops)
107 * DELETED - The ops are being deleted, do not let them be registered again.
108 * ADDING - The ops is in the process of being added.
109 * REMOVING - The ops is in the process of being removed.
110 * MODIFYING - The ops is in the process of changing its filter functions.
111 * ALLOC_TRAMP - A dynamic trampoline was allocated by the core code.
112 * The arch specific code sets this flag when it allocated a
113 * trampoline. This lets the arch know that it can update the
114 * trampoline in case the callback function changes.
115 * The ftrace_ops trampoline can be set by the ftrace users, and
116 * in such cases the arch must not modify it. Only the arch ftrace
117 * core code should set this flag.
118 * IPMODIFY - The ops can modify the IP register. This can only be set with
119 * SAVE_REGS. If another ops with this flag set is already registered
120 * for any of the functions that this ops will be registered for, then
121 * this ops will fail to register or set_filter_ip.
122 * PID - Is affected by set_ftrace_pid (allows filtering on those pids)
123 * RCU - Set when the ops can only be called when RCU is watching.
124 * TRACE_ARRAY - The ops->private points to a trace_array descriptor.
127 FTRACE_OPS_FL_ENABLED
= 1 << 0,
128 FTRACE_OPS_FL_DYNAMIC
= 1 << 1,
129 FTRACE_OPS_FL_PER_CPU
= 1 << 2,
130 FTRACE_OPS_FL_SAVE_REGS
= 1 << 3,
131 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED
= 1 << 4,
132 FTRACE_OPS_FL_RECURSION_SAFE
= 1 << 5,
133 FTRACE_OPS_FL_STUB
= 1 << 6,
134 FTRACE_OPS_FL_INITIALIZED
= 1 << 7,
135 FTRACE_OPS_FL_DELETED
= 1 << 8,
136 FTRACE_OPS_FL_ADDING
= 1 << 9,
137 FTRACE_OPS_FL_REMOVING
= 1 << 10,
138 FTRACE_OPS_FL_MODIFYING
= 1 << 11,
139 FTRACE_OPS_FL_ALLOC_TRAMP
= 1 << 12,
140 FTRACE_OPS_FL_IPMODIFY
= 1 << 13,
141 FTRACE_OPS_FL_PID
= 1 << 14,
142 FTRACE_OPS_FL_RCU
= 1 << 15,
143 FTRACE_OPS_FL_TRACE_ARRAY
= 1 << 16,
146 #ifdef CONFIG_DYNAMIC_FTRACE
147 /* The hash used to know what functions callbacks trace */
148 struct ftrace_ops_hash
{
149 struct ftrace_hash __rcu
*notrace_hash
;
150 struct ftrace_hash __rcu
*filter_hash
;
151 struct mutex regex_lock
;
154 void ftrace_free_init_mem(void);
156 static inline void ftrace_free_init_mem(void) { }
160 * Note, ftrace_ops can be referenced outside of RCU protection, unless
161 * the RCU flag is set. If ftrace_ops is allocated and not part of kernel
162 * core data, the unregistering of it will perform a scheduling on all CPUs
163 * to make sure that there are no more users. Depending on the load of the
164 * system that may take a bit of time.
166 * Any private data added must also take care not to be freed and if private
167 * data is added to a ftrace_ops that is in core code, the user of the
168 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
172 struct ftrace_ops __rcu
*next
;
175 ftrace_func_t saved_func
;
176 int __percpu
*disabled
;
177 #ifdef CONFIG_DYNAMIC_FTRACE
178 struct ftrace_ops_hash local_hash
;
179 struct ftrace_ops_hash
*func_hash
;
180 struct ftrace_ops_hash old_hash
;
181 unsigned long trampoline
;
182 unsigned long trampoline_size
;
187 * Type of the current tracing.
189 enum ftrace_tracing_type_t
{
190 FTRACE_TYPE_ENTER
= 0, /* Hook the call of the function */
191 FTRACE_TYPE_RETURN
, /* Hook the return of the function */
194 /* Current tracing type, default is FTRACE_TYPE_ENTER */
195 extern enum ftrace_tracing_type_t ftrace_tracing_type
;
198 * The ftrace_ops must be a static and should also
199 * be read_mostly. These functions do modify read_mostly variables
200 * so use them sparely. Never free an ftrace_op or modify the
201 * next pointer after it has been registered. Even after unregistering
202 * it, the next pointer may still be used internally.
204 int register_ftrace_function(struct ftrace_ops
*ops
);
205 int unregister_ftrace_function(struct ftrace_ops
*ops
);
206 void clear_ftrace_function(void);
209 * ftrace_function_local_enable - enable ftrace_ops on current cpu
211 * This function enables tracing on current cpu by decreasing
212 * the per cpu control variable.
213 * It must be called with preemption disabled and only on ftrace_ops
214 * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption
215 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
217 static inline void ftrace_function_local_enable(struct ftrace_ops
*ops
)
219 if (WARN_ON_ONCE(!(ops
->flags
& FTRACE_OPS_FL_PER_CPU
)))
222 (*this_cpu_ptr(ops
->disabled
))--;
226 * ftrace_function_local_disable - disable ftrace_ops on current cpu
228 * This function disables tracing on current cpu by increasing
229 * the per cpu control variable.
230 * It must be called with preemption disabled and only on ftrace_ops
231 * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption
232 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
234 static inline void ftrace_function_local_disable(struct ftrace_ops
*ops
)
236 if (WARN_ON_ONCE(!(ops
->flags
& FTRACE_OPS_FL_PER_CPU
)))
239 (*this_cpu_ptr(ops
->disabled
))++;
243 * ftrace_function_local_disabled - returns ftrace_ops disabled value
246 * This function returns value of ftrace_ops::disabled on current cpu.
247 * It must be called with preemption disabled and only on ftrace_ops
248 * registered with FTRACE_OPS_FL_PER_CPU. If called without preemption
249 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
251 static inline int ftrace_function_local_disabled(struct ftrace_ops
*ops
)
253 WARN_ON_ONCE(!(ops
->flags
& FTRACE_OPS_FL_PER_CPU
));
254 return *this_cpu_ptr(ops
->disabled
);
257 extern void ftrace_stub(unsigned long a0
, unsigned long a1
,
258 struct ftrace_ops
*op
, struct pt_regs
*regs
);
260 #else /* !CONFIG_FUNCTION_TRACER */
262 * (un)register_ftrace_function must be a macro since the ops parameter
263 * must not be evaluated.
265 #define register_ftrace_function(ops) ({ 0; })
266 #define unregister_ftrace_function(ops) ({ 0; })
267 static inline int ftrace_nr_registered_ops(void)
271 static inline void clear_ftrace_function(void) { }
272 static inline void ftrace_kill(void) { }
273 static inline void ftrace_free_init_mem(void) { }
274 #endif /* CONFIG_FUNCTION_TRACER */
276 #ifdef CONFIG_STACK_TRACER
278 #define STACK_TRACE_ENTRIES 500
282 extern unsigned stack_trace_index
[];
283 extern struct stack_trace stack_trace_max
;
284 extern unsigned long stack_trace_max_size
;
285 extern arch_spinlock_t stack_trace_max_lock
;
287 extern int stack_tracer_enabled
;
288 void stack_trace_print(void);
290 stack_trace_sysctl(struct ctl_table
*table
, int write
,
291 void __user
*buffer
, size_t *lenp
,
294 /* DO NOT MODIFY THIS VARIABLE DIRECTLY! */
295 DECLARE_PER_CPU(int, disable_stack_tracer
);
298 * stack_tracer_disable - temporarily disable the stack tracer
300 * There's a few locations (namely in RCU) where stack tracing
301 * cannot be executed. This function is used to disable stack
302 * tracing during those critical sections.
304 * This function must be called with preemption or interrupts
305 * disabled and stack_tracer_enable() must be called shortly after
306 * while preemption or interrupts are still disabled.
308 static inline void stack_tracer_disable(void)
310 /* Preemption or interupts must be disabled */
311 if (IS_ENABLED(CONFIG_DEBUG_PREEMPT
))
312 WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
313 this_cpu_inc(disable_stack_tracer
);
317 * stack_tracer_enable - re-enable the stack tracer
319 * After stack_tracer_disable() is called, stack_tracer_enable()
320 * must be called shortly afterward.
322 static inline void stack_tracer_enable(void)
324 if (IS_ENABLED(CONFIG_DEBUG_PREEMPT
))
325 WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
326 this_cpu_dec(disable_stack_tracer
);
329 static inline void stack_tracer_disable(void) { }
330 static inline void stack_tracer_enable(void) { }
333 #ifdef CONFIG_DYNAMIC_FTRACE
335 int ftrace_arch_code_modify_prepare(void);
336 int ftrace_arch_code_modify_post_process(void);
340 enum ftrace_bug_type
{
347 extern enum ftrace_bug_type ftrace_bug_type
;
350 * Archs can set this to point to a variable that holds the value that was
351 * expected at the call site before calling ftrace_bug().
353 extern const void *ftrace_expected
;
355 void ftrace_bug(int err
, struct dyn_ftrace
*rec
);
359 extern int ftrace_text_reserved(const void *start
, const void *end
);
361 extern int ftrace_nr_registered_ops(void);
363 bool is_ftrace_trampoline(unsigned long addr
);
366 * The dyn_ftrace record's flags field is split into two parts.
367 * the first part which is '0-FTRACE_REF_MAX' is a counter of
368 * the number of callbacks that have registered the function that
369 * the dyn_ftrace descriptor represents.
371 * The second part is a mask:
372 * ENABLED - the function is being traced
373 * REGS - the record wants the function to save regs
374 * REGS_EN - the function is set up to save regs.
375 * IPMODIFY - the record allows for the IP address to be changed.
376 * DISABLED - the record is not ready to be touched yet
378 * When a new ftrace_ops is registered and wants a function to save
379 * pt_regs, the rec->flag REGS is set. When the function has been
380 * set up to save regs, the REG_EN flag is set. Once a function
381 * starts saving regs it will do so until all ftrace_ops are removed
382 * from tracing that function.
385 FTRACE_FL_ENABLED
= (1UL << 31),
386 FTRACE_FL_REGS
= (1UL << 30),
387 FTRACE_FL_REGS_EN
= (1UL << 29),
388 FTRACE_FL_TRAMP
= (1UL << 28),
389 FTRACE_FL_TRAMP_EN
= (1UL << 27),
390 FTRACE_FL_IPMODIFY
= (1UL << 26),
391 FTRACE_FL_DISABLED
= (1UL << 25),
394 #define FTRACE_REF_MAX_SHIFT 25
395 #define FTRACE_FL_BITS 7
396 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
397 #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
398 #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
400 #define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK)
403 unsigned long ip
; /* address of mcount call-site */
405 struct dyn_arch_ftrace arch
;
408 int ftrace_force_update(void);
409 int ftrace_set_filter_ip(struct ftrace_ops
*ops
, unsigned long ip
,
410 int remove
, int reset
);
411 int ftrace_set_filter(struct ftrace_ops
*ops
, unsigned char *buf
,
413 int ftrace_set_notrace(struct ftrace_ops
*ops
, unsigned char *buf
,
415 void ftrace_set_global_filter(unsigned char *buf
, int len
, int reset
);
416 void ftrace_set_global_notrace(unsigned char *buf
, int len
, int reset
);
417 void ftrace_free_filter(struct ftrace_ops
*ops
);
418 void ftrace_ops_set_global_filter(struct ftrace_ops
*ops
);
421 FTRACE_UPDATE_CALLS
= (1 << 0),
422 FTRACE_DISABLE_CALLS
= (1 << 1),
423 FTRACE_UPDATE_TRACE_FUNC
= (1 << 2),
424 FTRACE_START_FUNC_RET
= (1 << 3),
425 FTRACE_STOP_FUNC_RET
= (1 << 4),
429 * The FTRACE_UPDATE_* enum is used to pass information back
430 * from the ftrace_update_record() and ftrace_test_record()
431 * functions. These are called by the code update routines
432 * to find out what is to be done for a given function.
434 * IGNORE - The function is already what we want it to be
435 * MAKE_CALL - Start tracing the function
436 * MODIFY_CALL - Stop saving regs for the function
437 * MAKE_NOP - Stop tracing the function
440 FTRACE_UPDATE_IGNORE
,
441 FTRACE_UPDATE_MAKE_CALL
,
442 FTRACE_UPDATE_MODIFY_CALL
,
443 FTRACE_UPDATE_MAKE_NOP
,
447 FTRACE_ITER_FILTER
= (1 << 0),
448 FTRACE_ITER_NOTRACE
= (1 << 1),
449 FTRACE_ITER_PRINTALL
= (1 << 2),
450 FTRACE_ITER_DO_PROBES
= (1 << 3),
451 FTRACE_ITER_PROBE
= (1 << 4),
452 FTRACE_ITER_MOD
= (1 << 5),
453 FTRACE_ITER_ENABLED
= (1 << 6),
456 void arch_ftrace_update_code(int command
);
458 struct ftrace_rec_iter
;
460 struct ftrace_rec_iter
*ftrace_rec_iter_start(void);
461 struct ftrace_rec_iter
*ftrace_rec_iter_next(struct ftrace_rec_iter
*iter
);
462 struct dyn_ftrace
*ftrace_rec_iter_record(struct ftrace_rec_iter
*iter
);
464 #define for_ftrace_rec_iter(iter) \
465 for (iter = ftrace_rec_iter_start(); \
467 iter = ftrace_rec_iter_next(iter))
470 int ftrace_update_record(struct dyn_ftrace
*rec
, int enable
);
471 int ftrace_test_record(struct dyn_ftrace
*rec
, int enable
);
472 void ftrace_run_stop_machine(int command
);
473 unsigned long ftrace_location(unsigned long ip
);
474 unsigned long ftrace_location_range(unsigned long start
, unsigned long end
);
475 unsigned long ftrace_get_addr_new(struct dyn_ftrace
*rec
);
476 unsigned long ftrace_get_addr_curr(struct dyn_ftrace
*rec
);
478 extern ftrace_func_t ftrace_trace_function
;
480 int ftrace_regex_open(struct ftrace_ops
*ops
, int flag
,
481 struct inode
*inode
, struct file
*file
);
482 ssize_t
ftrace_filter_write(struct file
*file
, const char __user
*ubuf
,
483 size_t cnt
, loff_t
*ppos
);
484 ssize_t
ftrace_notrace_write(struct file
*file
, const char __user
*ubuf
,
485 size_t cnt
, loff_t
*ppos
);
486 int ftrace_regex_release(struct inode
*inode
, struct file
*file
);
489 ftrace_set_early_filter(struct ftrace_ops
*ops
, char *buf
, int enable
);
491 /* defined in arch */
492 extern int ftrace_ip_converted(unsigned long ip
);
493 extern int ftrace_dyn_arch_init(void);
494 extern void ftrace_replace_code(int enable
);
495 extern int ftrace_update_ftrace_func(ftrace_func_t func
);
496 extern void ftrace_caller(void);
497 extern void ftrace_regs_caller(void);
498 extern void ftrace_call(void);
499 extern void ftrace_regs_call(void);
500 extern void mcount_call(void);
502 void ftrace_modify_all_code(int command
);
505 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
508 #ifndef FTRACE_GRAPH_ADDR
509 #define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
512 #ifndef FTRACE_REGS_ADDR
513 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
514 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
516 # define FTRACE_REGS_ADDR FTRACE_ADDR
521 * If an arch would like functions that are only traced
522 * by the function graph tracer to jump directly to its own
523 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
524 * to be that address to jump to.
526 #ifndef FTRACE_GRAPH_TRAMP_ADDR
527 #define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
530 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
531 extern void ftrace_graph_caller(void);
532 extern int ftrace_enable_ftrace_graph_caller(void);
533 extern int ftrace_disable_ftrace_graph_caller(void);
535 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
536 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
540 * ftrace_make_nop - convert code into nop
541 * @mod: module structure if called by module load initialization
542 * @rec: the mcount call site record
543 * @addr: the address that the call site should be calling
545 * This is a very sensitive operation and great care needs
546 * to be taken by the arch. The operation should carefully
547 * read the location, check to see if what is read is indeed
548 * what we expect it to be, and then on success of the compare,
549 * it should write to the location.
551 * The code segment at @rec->ip should be a caller to @addr
555 * -EFAULT on error reading the location
556 * -EINVAL on a failed compare of the contents
557 * -EPERM on error writing to the location
558 * Any other value will be considered a failure.
560 extern int ftrace_make_nop(struct module
*mod
,
561 struct dyn_ftrace
*rec
, unsigned long addr
);
564 * ftrace_make_call - convert a nop call site into a call to addr
565 * @rec: the mcount call site record
566 * @addr: the address that the call site should call
568 * This is a very sensitive operation and great care needs
569 * to be taken by the arch. The operation should carefully
570 * read the location, check to see if what is read is indeed
571 * what we expect it to be, and then on success of the compare,
572 * it should write to the location.
574 * The code segment at @rec->ip should be a nop
578 * -EFAULT on error reading the location
579 * -EINVAL on a failed compare of the contents
580 * -EPERM on error writing to the location
581 * Any other value will be considered a failure.
583 extern int ftrace_make_call(struct dyn_ftrace
*rec
, unsigned long addr
);
585 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
587 * ftrace_modify_call - convert from one addr to another (no nop)
588 * @rec: the mcount call site record
589 * @old_addr: the address expected to be currently called to
590 * @addr: the address to change to
592 * This is a very sensitive operation and great care needs
593 * to be taken by the arch. The operation should carefully
594 * read the location, check to see if what is read is indeed
595 * what we expect it to be, and then on success of the compare,
596 * it should write to the location.
598 * The code segment at @rec->ip should be a caller to @old_addr
602 * -EFAULT on error reading the location
603 * -EINVAL on a failed compare of the contents
604 * -EPERM on error writing to the location
605 * Any other value will be considered a failure.
607 extern int ftrace_modify_call(struct dyn_ftrace
*rec
, unsigned long old_addr
,
610 /* Should never be called */
611 static inline int ftrace_modify_call(struct dyn_ftrace
*rec
, unsigned long old_addr
,
618 /* May be defined in arch */
619 extern int ftrace_arch_read_dyn_info(char *buf
, int size
);
621 extern int skip_trace(unsigned long ip
);
622 extern void ftrace_module_init(struct module
*mod
);
623 extern void ftrace_module_enable(struct module
*mod
);
624 extern void ftrace_release_mod(struct module
*mod
);
626 extern void ftrace_disable_daemon(void);
627 extern void ftrace_enable_daemon(void);
628 #else /* CONFIG_DYNAMIC_FTRACE */
629 static inline int skip_trace(unsigned long ip
) { return 0; }
630 static inline int ftrace_force_update(void) { return 0; }
631 static inline void ftrace_disable_daemon(void) { }
632 static inline void ftrace_enable_daemon(void) { }
633 static inline void ftrace_module_init(struct module
*mod
) { }
634 static inline void ftrace_module_enable(struct module
*mod
) { }
635 static inline void ftrace_release_mod(struct module
*mod
) { }
636 static inline int ftrace_text_reserved(const void *start
, const void *end
)
640 static inline unsigned long ftrace_location(unsigned long ip
)
646 * Again users of functions that have ftrace_ops may not
647 * have them defined when ftrace is not enabled, but these
648 * functions may still be called. Use a macro instead of inline.
650 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
651 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
652 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
653 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
654 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
655 #define ftrace_free_filter(ops) do { } while (0)
656 #define ftrace_ops_set_global_filter(ops) do { } while (0)
658 static inline ssize_t
ftrace_filter_write(struct file
*file
, const char __user
*ubuf
,
659 size_t cnt
, loff_t
*ppos
) { return -ENODEV
; }
660 static inline ssize_t
ftrace_notrace_write(struct file
*file
, const char __user
*ubuf
,
661 size_t cnt
, loff_t
*ppos
) { return -ENODEV
; }
663 ftrace_regex_release(struct inode
*inode
, struct file
*file
) { return -ENODEV
; }
665 static inline bool is_ftrace_trampoline(unsigned long addr
)
669 #endif /* CONFIG_DYNAMIC_FTRACE */
671 /* totally disable ftrace - can not re-enable after this */
672 void ftrace_kill(void);
674 static inline void tracer_disable(void)
676 #ifdef CONFIG_FUNCTION_TRACER
682 * Ftrace disable/restore without lock. Some synchronization mechanism
683 * must be used to prevent ftrace_enabled to be changed between
686 static inline int __ftrace_enabled_save(void)
688 #ifdef CONFIG_FUNCTION_TRACER
689 int saved_ftrace_enabled
= ftrace_enabled
;
691 return saved_ftrace_enabled
;
697 static inline void __ftrace_enabled_restore(int enabled
)
699 #ifdef CONFIG_FUNCTION_TRACER
700 ftrace_enabled
= enabled
;
704 /* All archs should have this, but we define it for consistency */
705 #ifndef ftrace_return_address0
706 # define ftrace_return_address0 __builtin_return_address(0)
709 /* Archs may use other ways for ADDR1 and beyond */
710 #ifndef ftrace_return_address
711 # ifdef CONFIG_FRAME_POINTER
712 # define ftrace_return_address(n) __builtin_return_address(n)
714 # define ftrace_return_address(n) 0UL
718 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
719 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
720 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
721 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
722 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
723 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
724 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
726 static inline unsigned long get_lock_parent_ip(void)
728 unsigned long addr
= CALLER_ADDR0
;
730 if (!in_lock_functions(addr
))
733 if (!in_lock_functions(addr
))
738 #ifdef CONFIG_IRQSOFF_TRACER
739 extern void time_hardirqs_on(unsigned long a0
, unsigned long a1
);
740 extern void time_hardirqs_off(unsigned long a0
, unsigned long a1
);
742 static inline void time_hardirqs_on(unsigned long a0
, unsigned long a1
) { }
743 static inline void time_hardirqs_off(unsigned long a0
, unsigned long a1
) { }
746 #ifdef CONFIG_PREEMPT_TRACER
747 extern void trace_preempt_on(unsigned long a0
, unsigned long a1
);
748 extern void trace_preempt_off(unsigned long a0
, unsigned long a1
);
751 * Use defines instead of static inlines because some arches will make code out
752 * of the CALLER_ADDR, when we really want these to be a real nop.
754 # define trace_preempt_on(a0, a1) do { } while (0)
755 # define trace_preempt_off(a0, a1) do { } while (0)
758 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
759 extern void ftrace_init(void);
761 static inline void ftrace_init(void) { }
765 * Structure that defines an entry function trace.
766 * It's already packed but the attribute "packed" is needed
767 * to remove extra padding at the end.
769 struct ftrace_graph_ent
{
770 unsigned long func
; /* Current function */
775 * Structure that defines a return function trace.
776 * It's already packed but the attribute "packed" is needed
777 * to remove extra padding at the end.
779 struct ftrace_graph_ret
{
780 unsigned long func
; /* Current function */
781 /* Number of functions that overran the depth limit for current task */
782 unsigned long overrun
;
783 unsigned long long calltime
;
784 unsigned long long rettime
;
788 /* Type of the callback handlers for tracing function graph*/
789 typedef void (*trace_func_graph_ret_t
)(struct ftrace_graph_ret
*); /* return */
790 typedef int (*trace_func_graph_ent_t
)(struct ftrace_graph_ent
*); /* entry */
792 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
795 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
798 * Stack of return addresses for functions
800 * Used in struct thread_info
802 struct ftrace_ret_stack
{
805 unsigned long long calltime
;
806 #ifdef CONFIG_FUNCTION_PROFILER
807 unsigned long long subtime
;
809 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
812 #ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
818 * Primary handler of a function return.
819 * It relays on ftrace_return_to_handler.
820 * Defined in entry_32/64.S
822 extern void return_to_handler(void);
825 ftrace_push_return_trace(unsigned long ret
, unsigned long func
, int *depth
,
826 unsigned long frame_pointer
, unsigned long *retp
);
828 unsigned long ftrace_graph_ret_addr(struct task_struct
*task
, int *idx
,
829 unsigned long ret
, unsigned long *retp
);
832 * Sometimes we don't want to trace a function with the function
833 * graph tracer but we want them to keep traced by the usual function
834 * tracer if the function graph tracer is not configured.
836 #define __notrace_funcgraph notrace
838 #define FTRACE_NOTRACE_DEPTH 65536
839 #define FTRACE_RETFUNC_DEPTH 50
840 #define FTRACE_RETSTACK_ALLOC_SIZE 32
841 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
842 trace_func_graph_ent_t entryfunc
);
844 extern bool ftrace_graph_is_dead(void);
845 extern void ftrace_graph_stop(void);
847 /* The current handlers in use */
848 extern trace_func_graph_ret_t ftrace_graph_return
;
849 extern trace_func_graph_ent_t ftrace_graph_entry
;
851 extern void unregister_ftrace_graph(void);
853 extern void ftrace_graph_init_task(struct task_struct
*t
);
854 extern void ftrace_graph_exit_task(struct task_struct
*t
);
855 extern void ftrace_graph_init_idle_task(struct task_struct
*t
, int cpu
);
857 static inline int task_curr_ret_stack(struct task_struct
*t
)
859 return t
->curr_ret_stack
;
862 static inline void pause_graph_tracing(void)
864 atomic_inc(¤t
->tracing_graph_pause
);
867 static inline void unpause_graph_tracing(void)
869 atomic_dec(¤t
->tracing_graph_pause
);
871 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
873 #define __notrace_funcgraph
874 #define INIT_FTRACE_GRAPH
876 static inline void ftrace_graph_init_task(struct task_struct
*t
) { }
877 static inline void ftrace_graph_exit_task(struct task_struct
*t
) { }
878 static inline void ftrace_graph_init_idle_task(struct task_struct
*t
, int cpu
) { }
880 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc
,
881 trace_func_graph_ent_t entryfunc
)
885 static inline void unregister_ftrace_graph(void) { }
887 static inline int task_curr_ret_stack(struct task_struct
*tsk
)
892 static inline unsigned long
893 ftrace_graph_ret_addr(struct task_struct
*task
, int *idx
, unsigned long ret
,
899 static inline void pause_graph_tracing(void) { }
900 static inline void unpause_graph_tracing(void) { }
901 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
903 #ifdef CONFIG_TRACING
905 /* flags for current->trace */
907 TSK_TRACE_FL_TRACE_BIT
= 0,
908 TSK_TRACE_FL_GRAPH_BIT
= 1,
911 TSK_TRACE_FL_TRACE
= 1 << TSK_TRACE_FL_TRACE_BIT
,
912 TSK_TRACE_FL_GRAPH
= 1 << TSK_TRACE_FL_GRAPH_BIT
,
915 static inline void set_tsk_trace_trace(struct task_struct
*tsk
)
917 set_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
920 static inline void clear_tsk_trace_trace(struct task_struct
*tsk
)
922 clear_bit(TSK_TRACE_FL_TRACE_BIT
, &tsk
->trace
);
925 static inline int test_tsk_trace_trace(struct task_struct
*tsk
)
927 return tsk
->trace
& TSK_TRACE_FL_TRACE
;
930 static inline void set_tsk_trace_graph(struct task_struct
*tsk
)
932 set_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
935 static inline void clear_tsk_trace_graph(struct task_struct
*tsk
)
937 clear_bit(TSK_TRACE_FL_GRAPH_BIT
, &tsk
->trace
);
940 static inline int test_tsk_trace_graph(struct task_struct
*tsk
)
942 return tsk
->trace
& TSK_TRACE_FL_GRAPH
;
945 enum ftrace_dump_mode
;
947 extern enum ftrace_dump_mode ftrace_dump_on_oops
;
948 extern int tracepoint_printk
;
950 extern void disable_trace_on_warning(void);
951 extern int __disable_trace_on_warning
;
953 #ifdef CONFIG_PREEMPT
954 #define INIT_TRACE_RECURSION .trace_recursion = 0,
957 int tracepoint_printk_sysctl(struct ctl_table
*table
, int write
,
958 void __user
*buffer
, size_t *lenp
,
961 #else /* CONFIG_TRACING */
962 static inline void disable_trace_on_warning(void) { }
963 #endif /* CONFIG_TRACING */
965 #ifndef INIT_TRACE_RECURSION
966 #define INIT_TRACE_RECURSION
969 #ifdef CONFIG_FTRACE_SYSCALLS
971 unsigned long arch_syscall_addr(int nr
);
973 #endif /* CONFIG_FTRACE_SYSCALLS */
975 #endif /* _LINUX_FTRACE_H */