1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Ftrace header. For implementation details beyond the random comments
4 * scattered below, see: Documentation/trace/ftrace-design.rst
5 */
6
7#ifndef _LINUX_FTRACE_H
8#define _LINUX_FTRACE_H
9
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>
19#include <linux/fs.h>
20
21#include <asm/ftrace.h>
22
23/*
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.
27 */
28#ifndef ARCH_SUPPORTS_FTRACE_OPS
29#define ARCH_SUPPORTS_FTRACE_OPS 0
30#endif
31
32/*
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.
36 */
37#if !ARCH_SUPPORTS_FTRACE_OPS
38# define FTRACE_FORCE_LIST_FUNC 1
39#else
40# define FTRACE_FORCE_LIST_FUNC 0
41#endif
42
43/* Main tracing buffer and events set up */
44#ifdef CONFIG_TRACING
45void trace_init(void);
46void early_trace_init(void);
47#else
48static inline void trace_init(void) { }
49static inline void early_trace_init(void) { }
50#endif
51
52struct module;
53struct ftrace_hash;
54
55#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_MODULES) && \
56 defined(CONFIG_DYNAMIC_FTRACE)
57const char *
58ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
59 unsigned long *off, char **modname, char *sym);
60int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value,
61 char *type, char *name,
62 char *module_name, int *exported);
63#else
64static inline const char *
65ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
66 unsigned long *off, char **modname, char *sym)
67{
68 return NULL;
69}
70static inline int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value,
71 char *type, char *name,
72 char *module_name, int *exported)
73{
74 return -1;
75}
76#endif
77
78
79#ifdef CONFIG_FUNCTION_TRACER
80
81extern int ftrace_enabled;
82extern int
83ftrace_enable_sysctl(struct ctl_table *table, int write,
84 void __user *buffer, size_t *lenp,
85 loff_t *ppos);
86
87struct ftrace_ops;
88
89typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
90 struct ftrace_ops *op, struct pt_regs *regs);
91
92ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops);
93
94/*
95 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
96 * set in the flags member.
97 * CONTROL, SAVE_REGS, SAVE_REGS_IF_SUPPORTED, RECURSION_SAFE, STUB and
98 * IPMODIFY are a kind of attribute flags which can be set only before
99 * registering the ftrace_ops, and can not be modified while registered.
100 * Changing those attribute flags after registering ftrace_ops will
101 * cause unexpected results.
102 *
103 * ENABLED - set/unset when ftrace_ops is registered/unregistered
104 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
105 * allocated ftrace_ops which need special care
106 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
107 * and passed to the callback. If this flag is set, but the
108 * architecture does not support passing regs
109 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
110 * ftrace_ops will fail to register, unless the next flag
111 * is set.
112 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
113 * handler can handle an arch that does not save regs
114 * (the handler tests if regs == NULL), then it can set
115 * this flag instead. It will not fail registering the ftrace_ops
116 * but, the regs field will be NULL if the arch does not support
117 * passing regs to the handler.
118 * Note, if this flag is set, the SAVE_REGS flag will automatically
119 * get set upon registering the ftrace_ops, if the arch supports it.
120 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
121 * that the call back has its own recursion protection. If it does
122 * not set this, then the ftrace infrastructure will add recursion
123 * protection for the caller.
124 * STUB - The ftrace_ops is just a place holder.
125 * INITIALIZED - The ftrace_ops has already been initialized (first use time
126 * register_ftrace_function() is called, it will initialized the ops)
127 * DELETED - The ops are being deleted, do not let them be registered again.
128 * ADDING - The ops is in the process of being added.
129 * REMOVING - The ops is in the process of being removed.
130 * MODIFYING - The ops is in the process of changing its filter functions.
131 * ALLOC_TRAMP - A dynamic trampoline was allocated by the core code.
132 * The arch specific code sets this flag when it allocated a
133 * trampoline. This lets the arch know that it can update the
134 * trampoline in case the callback function changes.
135 * The ftrace_ops trampoline can be set by the ftrace users, and
136 * in such cases the arch must not modify it. Only the arch ftrace
137 * core code should set this flag.
138 * IPMODIFY - The ops can modify the IP register. This can only be set with
139 * SAVE_REGS. If another ops with this flag set is already registered
140 * for any of the functions that this ops will be registered for, then
141 * this ops will fail to register or set_filter_ip.
142 * PID - Is affected by set_ftrace_pid (allows filtering on those pids)
143 * RCU - Set when the ops can only be called when RCU is watching.
144 * TRACE_ARRAY - The ops->private points to a trace_array descriptor.
145 */
146enum {
147 FTRACE_OPS_FL_ENABLED = 1 << 0,
148 FTRACE_OPS_FL_DYNAMIC = 1 << 1,
149 FTRACE_OPS_FL_SAVE_REGS = 1 << 2,
150 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 3,
151 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 4,
152 FTRACE_OPS_FL_STUB = 1 << 5,
153 FTRACE_OPS_FL_INITIALIZED = 1 << 6,
154 FTRACE_OPS_FL_DELETED = 1 << 7,
155 FTRACE_OPS_FL_ADDING = 1 << 8,
156 FTRACE_OPS_FL_REMOVING = 1 << 9,
157 FTRACE_OPS_FL_MODIFYING = 1 << 10,
158 FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 11,
159 FTRACE_OPS_FL_IPMODIFY = 1 << 12,
160 FTRACE_OPS_FL_PID = 1 << 13,
161 FTRACE_OPS_FL_RCU = 1 << 14,
162 FTRACE_OPS_FL_TRACE_ARRAY = 1 << 15,
163};
164
165#ifdef CONFIG_DYNAMIC_FTRACE
166/* The hash used to know what functions callbacks trace */
167struct ftrace_ops_hash {
168 struct ftrace_hash __rcu *notrace_hash;
169 struct ftrace_hash __rcu *filter_hash;
170 struct mutex regex_lock;
171};
172
173void ftrace_free_init_mem(void);
174void ftrace_free_mem(struct module *mod, void *start, void *end);
175#else
176static inline void ftrace_free_init_mem(void) { }
177static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { }
178#endif
179
180/*
181 * Note, ftrace_ops can be referenced outside of RCU protection, unless
182 * the RCU flag is set. If ftrace_ops is allocated and not part of kernel
183 * core data, the unregistering of it will perform a scheduling on all CPUs
184 * to make sure that there are no more users. Depending on the load of the
185 * system that may take a bit of time.
186 *
187 * Any private data added must also take care not to be freed and if private
188 * data is added to a ftrace_ops that is in core code, the user of the
189 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
190 */
191struct ftrace_ops {
192 ftrace_func_t func;
193 struct ftrace_ops __rcu *next;
194 unsigned long flags;
195 void *private;
196 ftrace_func_t saved_func;
197#ifdef CONFIG_DYNAMIC_FTRACE
198 struct ftrace_ops_hash local_hash;
199 struct ftrace_ops_hash *func_hash;
200 struct ftrace_ops_hash old_hash;
201 unsigned long trampoline;
202 unsigned long trampoline_size;
203#endif
204};
205
206/*
207 * Type of the current tracing.
208 */
209enum ftrace_tracing_type_t {
210 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
211 FTRACE_TYPE_RETURN, /* Hook the return of the function */
212};
213
214/* Current tracing type, default is FTRACE_TYPE_ENTER */
215extern enum ftrace_tracing_type_t ftrace_tracing_type;
216
217/*
218 * The ftrace_ops must be a static and should also
219 * be read_mostly. These functions do modify read_mostly variables
220 * so use them sparely. Never free an ftrace_op or modify the
221 * next pointer after it has been registered. Even after unregistering
222 * it, the next pointer may still be used internally.
223 */
224int register_ftrace_function(struct ftrace_ops *ops);
225int unregister_ftrace_function(struct ftrace_ops *ops);
226
227extern void ftrace_stub(unsigned long a0, unsigned long a1,
228 struct ftrace_ops *op, struct pt_regs *regs);
229
230#else /* !CONFIG_FUNCTION_TRACER */
231/*
232 * (un)register_ftrace_function must be a macro since the ops parameter
233 * must not be evaluated.
234 */
235#define register_ftrace_function(ops) ({ 0; })
236#define unregister_ftrace_function(ops) ({ 0; })
237static inline void ftrace_kill(void) { }
238static inline void ftrace_free_init_mem(void) { }
239static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { }
240#endif /* CONFIG_FUNCTION_TRACER */
241
242#ifdef CONFIG_STACK_TRACER
243
244#define STACK_TRACE_ENTRIES 500
245
246struct stack_trace;
247
248extern unsigned stack_trace_index[];
249extern struct stack_trace stack_trace_max;
250extern unsigned long stack_trace_max_size;
251extern arch_spinlock_t stack_trace_max_lock;
252
253extern int stack_tracer_enabled;
254void stack_trace_print(void);
255int
256stack_trace_sysctl(struct ctl_table *table, int write,
257 void __user *buffer, size_t *lenp,
258 loff_t *ppos);
259
260/* DO NOT MODIFY THIS VARIABLE DIRECTLY! */
261DECLARE_PER_CPU(int, disable_stack_tracer);
262
263/**
264 * stack_tracer_disable - temporarily disable the stack tracer
265 *
266 * There's a few locations (namely in RCU) where stack tracing
267 * cannot be executed. This function is used to disable stack
268 * tracing during those critical sections.
269 *
270 * This function must be called with preemption or interrupts
271 * disabled and stack_tracer_enable() must be called shortly after
272 * while preemption or interrupts are still disabled.
273 */
274static inline void stack_tracer_disable(void)
275{
276 /* Preemption or interupts must be disabled */
277 if (IS_ENABLED(CONFIG_DEBUG_PREEMPT))
278 WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
279 this_cpu_inc(disable_stack_tracer);
280}
281
282/**
283 * stack_tracer_enable - re-enable the stack tracer
284 *
285 * After stack_tracer_disable() is called, stack_tracer_enable()
286 * must be called shortly afterward.
287 */
288static inline void stack_tracer_enable(void)
289{
290 if (IS_ENABLED(CONFIG_DEBUG_PREEMPT))
291 WARN_ON_ONCE(!preempt_count() || !irqs_disabled());
292 this_cpu_dec(disable_stack_tracer);
293}
294#else
295static inline void stack_tracer_disable(void) { }
296static inline void stack_tracer_enable(void) { }
297#endif
298
299#ifdef CONFIG_DYNAMIC_FTRACE
300
301int ftrace_arch_code_modify_prepare(void);
302int ftrace_arch_code_modify_post_process(void);
303
304struct dyn_ftrace;
305
306enum ftrace_bug_type {
307 FTRACE_BUG_UNKNOWN,
308 FTRACE_BUG_INIT,
309 FTRACE_BUG_NOP,
310 FTRACE_BUG_CALL,
311 FTRACE_BUG_UPDATE,
312};
313extern enum ftrace_bug_type ftrace_bug_type;
314
315/*
316 * Archs can set this to point to a variable that holds the value that was
317 * expected at the call site before calling ftrace_bug().
318 */
319extern const void *ftrace_expected;
320
321void ftrace_bug(int err, struct dyn_ftrace *rec);
322
323struct seq_file;
324
325extern int ftrace_text_reserved(const void *start, const void *end);
326
327struct ftrace_ops *ftrace_ops_trampoline(unsigned long addr);
328
329bool is_ftrace_trampoline(unsigned long addr);
330
331/*
332 * The dyn_ftrace record's flags field is split into two parts.
333 * the first part which is '0-FTRACE_REF_MAX' is a counter of
334 * the number of callbacks that have registered the function that
335 * the dyn_ftrace descriptor represents.
336 *
337 * The second part is a mask:
338 * ENABLED - the function is being traced
339 * REGS - the record wants the function to save regs
340 * REGS_EN - the function is set up to save regs.
341 * IPMODIFY - the record allows for the IP address to be changed.
342 * DISABLED - the record is not ready to be touched yet
343 *
344 * When a new ftrace_ops is registered and wants a function to save
345 * pt_regs, the rec->flag REGS is set. When the function has been
346 * set up to save regs, the REG_EN flag is set. Once a function
347 * starts saving regs it will do so until all ftrace_ops are removed
348 * from tracing that function.
349 */
350enum {
351 FTRACE_FL_ENABLED = (1UL << 31),
352 FTRACE_FL_REGS = (1UL << 30),
353 FTRACE_FL_REGS_EN = (1UL << 29),
354 FTRACE_FL_TRAMP = (1UL << 28),
355 FTRACE_FL_TRAMP_EN = (1UL << 27),
356 FTRACE_FL_IPMODIFY = (1UL << 26),
357 FTRACE_FL_DISABLED = (1UL << 25),
358};
359
360#define FTRACE_REF_MAX_SHIFT 25
361#define FTRACE_FL_BITS 7
362#define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
363#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
364#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
365
366#define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK)
367
368struct dyn_ftrace {
369 unsigned long ip; /* address of mcount call-site */
370 unsigned long flags;
371 struct dyn_arch_ftrace arch;
372};
373
374int ftrace_force_update(void);
375int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
376 int remove, int reset);
377int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
378 int len, int reset);
379int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
380 int len, int reset);
381void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
382void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
383void ftrace_free_filter(struct ftrace_ops *ops);
384void ftrace_ops_set_global_filter(struct ftrace_ops *ops);
385
386enum {
387 FTRACE_UPDATE_CALLS = (1 << 0),
388 FTRACE_DISABLE_CALLS = (1 << 1),
389 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
390 FTRACE_START_FUNC_RET = (1 << 3),
391 FTRACE_STOP_FUNC_RET = (1 << 4),
392 FTRACE_MAY_SLEEP = (1 << 5),
393};
394
395/*
396 * The FTRACE_UPDATE_* enum is used to pass information back
397 * from the ftrace_update_record() and ftrace_test_record()
398 * functions. These are called by the code update routines
399 * to find out what is to be done for a given function.
400 *
401 * IGNORE - The function is already what we want it to be
402 * MAKE_CALL - Start tracing the function
403 * MODIFY_CALL - Stop saving regs for the function
404 * MAKE_NOP - Stop tracing the function
405 */
406enum {
407 FTRACE_UPDATE_IGNORE,
408 FTRACE_UPDATE_MAKE_CALL,
409 FTRACE_UPDATE_MODIFY_CALL,
410 FTRACE_UPDATE_MAKE_NOP,
411};
412
413enum {
414 FTRACE_ITER_FILTER = (1 << 0),
415 FTRACE_ITER_NOTRACE = (1 << 1),
416 FTRACE_ITER_PRINTALL = (1 << 2),
417 FTRACE_ITER_DO_PROBES = (1 << 3),
418 FTRACE_ITER_PROBE = (1 << 4),
419 FTRACE_ITER_MOD = (1 << 5),
420 FTRACE_ITER_ENABLED = (1 << 6),
421};
422
423void arch_ftrace_update_code(int command);
424void arch_ftrace_update_trampoline(struct ftrace_ops *ops);
425void *arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec);
426void arch_ftrace_trampoline_free(struct ftrace_ops *ops);
427
428struct ftrace_rec_iter;
429
430struct ftrace_rec_iter *ftrace_rec_iter_start(void);
431struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
432struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
433
434#define for_ftrace_rec_iter(iter) \
435 for (iter = ftrace_rec_iter_start(); \
436 iter; \
437 iter = ftrace_rec_iter_next(iter))
438
439
440int ftrace_update_record(struct dyn_ftrace *rec, int enable);
441int ftrace_test_record(struct dyn_ftrace *rec, int enable);
442void ftrace_run_stop_machine(int command);
443unsigned long ftrace_location(unsigned long ip);
444unsigned long ftrace_location_range(unsigned long start, unsigned long end);
445unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
446unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
447
448extern ftrace_func_t ftrace_trace_function;
449
450int ftrace_regex_open(struct ftrace_ops *ops, int flag,
451 struct inode *inode, struct file *file);
452ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
453 size_t cnt, loff_t *ppos);
454ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
455 size_t cnt, loff_t *ppos);
456int ftrace_regex_release(struct inode *inode, struct file *file);
457
458void __init
459ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
460
461/* defined in arch */
462extern int ftrace_ip_converted(unsigned long ip);
463extern int ftrace_dyn_arch_init(void);
464extern void ftrace_replace_code(int enable);
465extern int ftrace_update_ftrace_func(ftrace_func_t func);
466extern void ftrace_caller(void);
467extern void ftrace_regs_caller(void);
468extern void ftrace_call(void);
469extern void ftrace_regs_call(void);
470extern void mcount_call(void);
471
472void ftrace_modify_all_code(int command);
473
474#ifndef FTRACE_ADDR
475#define FTRACE_ADDR ((unsigned long)ftrace_caller)
476#endif
477
478#ifndef FTRACE_GRAPH_ADDR
479#define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
480#endif
481
482#ifndef FTRACE_REGS_ADDR
483#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
484# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
485#else
486# define FTRACE_REGS_ADDR FTRACE_ADDR
487#endif
488#endif
489
490/*
491 * If an arch would like functions that are only traced
492 * by the function graph tracer to jump directly to its own
493 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
494 * to be that address to jump to.
495 */
496#ifndef FTRACE_GRAPH_TRAMP_ADDR
497#define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
498#endif
499
500#ifdef CONFIG_FUNCTION_GRAPH_TRACER
501extern void ftrace_graph_caller(void);
502extern int ftrace_enable_ftrace_graph_caller(void);
503extern int ftrace_disable_ftrace_graph_caller(void);
504#else
505static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
506static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
507#endif
508
509/**
510 * ftrace_make_nop - convert code into nop
511 * @mod: module structure if called by module load initialization
512 * @rec: the mcount call site record
513 * @addr: the address that the call site should be calling
514 *
515 * This is a very sensitive operation and great care needs
516 * to be taken by the arch. The operation should carefully
517 * read the location, check to see if what is read is indeed
518 * what we expect it to be, and then on success of the compare,
519 * it should write to the location.
520 *
521 * The code segment at @rec->ip should be a caller to @addr
522 *
523 * Return must be:
524 * 0 on success
525 * -EFAULT on error reading the location
526 * -EINVAL on a failed compare of the contents
527 * -EPERM on error writing to the location
528 * Any other value will be considered a failure.
529 */
530extern int ftrace_make_nop(struct module *mod,
531 struct dyn_ftrace *rec, unsigned long addr);
532
533/**
534 * ftrace_make_call - convert a nop call site into a call to addr
535 * @rec: the mcount call site record
536 * @addr: the address that the call site should call
537 *
538 * This is a very sensitive operation and great care needs
539 * to be taken by the arch. The operation should carefully
540 * read the location, check to see if what is read is indeed
541 * what we expect it to be, and then on success of the compare,
542 * it should write to the location.
543 *
544 * The code segment at @rec->ip should be a nop
545 *
546 * Return must be:
547 * 0 on success
548 * -EFAULT on error reading the location
549 * -EINVAL on a failed compare of the contents
550 * -EPERM on error writing to the location
551 * Any other value will be considered a failure.
552 */
553extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
554
555#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
556/**
557 * ftrace_modify_call - convert from one addr to another (no nop)
558 * @rec: the mcount call site record
559 * @old_addr: the address expected to be currently called to
560 * @addr: the address to change to
561 *
562 * This is a very sensitive operation and great care needs
563 * to be taken by the arch. The operation should carefully
564 * read the location, check to see if what is read is indeed
565 * what we expect it to be, and then on success of the compare,
566 * it should write to the location.
567 *
568 * The code segment at @rec->ip should be a caller to @old_addr
569 *
570 * Return must be:
571 * 0 on success
572 * -EFAULT on error reading the location
573 * -EINVAL on a failed compare of the contents
574 * -EPERM on error writing to the location
575 * Any other value will be considered a failure.
576 */
577extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
578 unsigned long addr);
579#else
580/* Should never be called */
581static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
582 unsigned long addr)
583{
584 return -EINVAL;
585}
586#endif
587
588/* May be defined in arch */
589extern int ftrace_arch_read_dyn_info(char *buf, int size);
590
591extern int skip_trace(unsigned long ip);
592extern void ftrace_module_init(struct module *mod);
593extern void ftrace_module_enable(struct module *mod);
594extern void ftrace_release_mod(struct module *mod);
595
596extern void ftrace_disable_daemon(void);
597extern void ftrace_enable_daemon(void);
598#else /* CONFIG_DYNAMIC_FTRACE */
599static inline int skip_trace(unsigned long ip) { return 0; }
600static inline int ftrace_force_update(void) { return 0; }
601static inline void ftrace_disable_daemon(void) { }
602static inline void ftrace_enable_daemon(void) { }
603static inline void ftrace_module_init(struct module *mod) { }
604static inline void ftrace_module_enable(struct module *mod) { }
605static inline void ftrace_release_mod(struct module *mod) { }
606static inline int ftrace_text_reserved(const void *start, const void *end)
607{
608 return 0;
609}
610static inline unsigned long ftrace_location(unsigned long ip)
611{
612 return 0;
613}
614
615/*
616 * Again users of functions that have ftrace_ops may not
617 * have them defined when ftrace is not enabled, but these
618 * functions may still be called. Use a macro instead of inline.
619 */
620#define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
621#define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
622#define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
623#define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
624#define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
625#define ftrace_free_filter(ops) do { } while (0)
626#define ftrace_ops_set_global_filter(ops) do { } while (0)
627
628static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
629 size_t cnt, loff_t *ppos) { return -ENODEV; }
630static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
631 size_t cnt, loff_t *ppos) { return -ENODEV; }
632static inline int
633ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
634
635static inline bool is_ftrace_trampoline(unsigned long addr)
636{
637 return false;
638}
639#endif /* CONFIG_DYNAMIC_FTRACE */
640
641/* totally disable ftrace - can not re-enable after this */
642void ftrace_kill(void);
643
644static inline void tracer_disable(void)
645{
646#ifdef CONFIG_FUNCTION_TRACER
647 ftrace_enabled = 0;
648#endif
649}
650
651/*
652 * Ftrace disable/restore without lock. Some synchronization mechanism
653 * must be used to prevent ftrace_enabled to be changed between
654 * disable/restore.
655 */
656static inline int __ftrace_enabled_save(void)
657{
658#ifdef CONFIG_FUNCTION_TRACER
659 int saved_ftrace_enabled = ftrace_enabled;
660 ftrace_enabled = 0;
661 return saved_ftrace_enabled;
662#else
663 return 0;
664#endif
665}
666
667static inline void __ftrace_enabled_restore(int enabled)
668{
669#ifdef CONFIG_FUNCTION_TRACER
670 ftrace_enabled = enabled;
671#endif
672}
673
674/* All archs should have this, but we define it for consistency */
675#ifndef ftrace_return_address0
676# define ftrace_return_address0 __builtin_return_address(0)
677#endif
678
679/* Archs may use other ways for ADDR1 and beyond */
680#ifndef ftrace_return_address
681# ifdef CONFIG_FRAME_POINTER
682# define ftrace_return_address(n) __builtin_return_address(n)
683# else
684# define ftrace_return_address(n) 0UL
685# endif
686#endif
687
688#define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
689#define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
690#define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
691#define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
692#define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
693#define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
694#define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
695
696static inline unsigned long get_lock_parent_ip(void)
697{
698 unsigned long addr = CALLER_ADDR0;
699
700 if (!in_lock_functions(addr))
701 return addr;
702 addr = CALLER_ADDR1;
703 if (!in_lock_functions(addr))
704 return addr;
705 return CALLER_ADDR2;
706}
707
708#ifdef CONFIG_TRACE_PREEMPT_TOGGLE
709 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
710 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
711#else
712/*
713 * Use defines instead of static inlines because some arches will make code out
714 * of the CALLER_ADDR, when we really want these to be a real nop.
715 */
716# define trace_preempt_on(a0, a1) do { } while (0)
717# define trace_preempt_off(a0, a1) do { } while (0)
718#endif
719
720#ifdef CONFIG_FTRACE_MCOUNT_RECORD
721extern void ftrace_init(void);
722#else
723static inline void ftrace_init(void) { }
724#endif
725
726/*
727 * Structure that defines an entry function trace.
728 * It's already packed but the attribute "packed" is needed
729 * to remove extra padding at the end.
730 */
731struct ftrace_graph_ent {
732 unsigned long func; /* Current function */
733 int depth;
734} __packed;
735
736/*
737 * Structure that defines a return function trace.
738 * It's already packed but the attribute "packed" is needed
739 * to remove extra padding at the end.
740 */
741struct ftrace_graph_ret {
742 unsigned long func; /* Current function */
743 /* Number of functions that overran the depth limit for current task */
744 unsigned long overrun;
745 unsigned long long calltime;
746 unsigned long long rettime;
747 int depth;
748} __packed;
749
750/* Type of the callback handlers for tracing function graph*/
751typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
752typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
753
754#ifdef CONFIG_FUNCTION_GRAPH_TRACER
755
756struct fgraph_ops {
757 trace_func_graph_ent_t entryfunc;
758 trace_func_graph_ret_t retfunc;
759};
760
761/*
762 * Stack of return addresses for functions
763 * of a thread.
764 * Used in struct thread_info
765 */
766struct ftrace_ret_stack {
767 unsigned long ret;
768 unsigned long func;
769 unsigned long long calltime;
770#ifdef CONFIG_FUNCTION_PROFILER
771 unsigned long long subtime;
772#endif
773#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
774 unsigned long fp;
775#endif
776#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
777 unsigned long *retp;
778#endif
779};
780
781/*
782 * Primary handler of a function return.
783 * It relays on ftrace_return_to_handler.
784 * Defined in entry_32/64.S
785 */
786extern void return_to_handler(void);
787
788extern int
789function_graph_enter(unsigned long ret, unsigned long func,
790 unsigned long frame_pointer, unsigned long *retp);
791
792struct ftrace_ret_stack *
793ftrace_graph_get_ret_stack(struct task_struct *task, int idx);
794
795unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
796 unsigned long ret, unsigned long *retp);
797
798/*
799 * Sometimes we don't want to trace a function with the function
800 * graph tracer but we want them to keep traced by the usual function
801 * tracer if the function graph tracer is not configured.
802 */
803#define __notrace_funcgraph notrace
804
805#define FTRACE_RETFUNC_DEPTH 50
806#define FTRACE_RETSTACK_ALLOC_SIZE 32
807
808extern int register_ftrace_graph(struct fgraph_ops *ops);
809extern void unregister_ftrace_graph(struct fgraph_ops *ops);
810
811extern bool ftrace_graph_is_dead(void);
812extern void ftrace_graph_stop(void);
813
814/* The current handlers in use */
815extern trace_func_graph_ret_t ftrace_graph_return;
816extern trace_func_graph_ent_t ftrace_graph_entry;
817
818extern void ftrace_graph_init_task(struct task_struct *t);
819extern void ftrace_graph_exit_task(struct task_struct *t);
820extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
821
822static inline void pause_graph_tracing(void)
823{
824 atomic_inc(&current->tracing_graph_pause);
825}
826
827static inline void unpause_graph_tracing(void)
828{
829 atomic_dec(&current->tracing_graph_pause);
830}
831#else /* !CONFIG_FUNCTION_GRAPH_TRACER */
832
833#define __notrace_funcgraph
834
835static inline void ftrace_graph_init_task(struct task_struct *t) { }
836static inline void ftrace_graph_exit_task(struct task_struct *t) { }
837static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
838
839/* Define as macros as fgraph_ops may not be defined */
840#define register_ftrace_graph(ops) ({ -1; })
841#define unregister_ftrace_graph(ops) do { } while (0)
842
843static inline unsigned long
844ftrace_graph_ret_addr(struct task_struct *task, int *idx, unsigned long ret,
845 unsigned long *retp)
846{
847 return ret;
848}
849
850static inline void pause_graph_tracing(void) { }
851static inline void unpause_graph_tracing(void) { }
852#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
853
854#ifdef CONFIG_TRACING
855
856/* flags for current->trace */
857enum {
858 TSK_TRACE_FL_TRACE_BIT = 0,
859 TSK_TRACE_FL_GRAPH_BIT = 1,
860};
861enum {
862 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
863 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
864};
865
866static inline void set_tsk_trace_trace(struct task_struct *tsk)
867{
868 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
869}
870
871static inline void clear_tsk_trace_trace(struct task_struct *tsk)
872{
873 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
874}
875
876static inline int test_tsk_trace_trace(struct task_struct *tsk)
877{
878 return tsk->trace & TSK_TRACE_FL_TRACE;
879}
880
881static inline void set_tsk_trace_graph(struct task_struct *tsk)
882{
883 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
884}
885
886static inline void clear_tsk_trace_graph(struct task_struct *tsk)
887{
888 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
889}
890
891static inline int test_tsk_trace_graph(struct task_struct *tsk)
892{
893 return tsk->trace & TSK_TRACE_FL_GRAPH;
894}
895
896enum ftrace_dump_mode;
897
898extern enum ftrace_dump_mode ftrace_dump_on_oops;
899extern int tracepoint_printk;
900
901extern void disable_trace_on_warning(void);
902extern int __disable_trace_on_warning;
903
904int tracepoint_printk_sysctl(struct ctl_table *table, int write,
905 void __user *buffer, size_t *lenp,
906 loff_t *ppos);
907
908#else /* CONFIG_TRACING */
909static inline void disable_trace_on_warning(void) { }
910#endif /* CONFIG_TRACING */
911
912#ifdef CONFIG_FTRACE_SYSCALLS
913
914unsigned long arch_syscall_addr(int nr);
915
916#endif /* CONFIG_FTRACE_SYSCALLS */
917
918#endif /* _LINUX_FTRACE_H */
919