1 /*
2 * Ftrace header. For implementation details beyond the random comments
3 * scattered below, see: Documentation/trace/ftrace-design.txt
4 */
5
6 #ifndef _LINUX_FTRACE_H
7 #define _LINUX_FTRACE_H
8
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>
18 #include <linux/fs.h>
19
20 #include <asm/ftrace.h>
21
22 /*
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.
26 */
27 #ifndef ARCH_SUPPORTS_FTRACE_OPS
28 #define ARCH_SUPPORTS_FTRACE_OPS 0
29 #endif
30
31 /*
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.
35 */
36 #if !ARCH_SUPPORTS_FTRACE_OPS
37 # define FTRACE_FORCE_LIST_FUNC 1
38 #else
39 # define FTRACE_FORCE_LIST_FUNC 0
40 #endif
41
42 /* Main tracing buffer and events set up */
43 #ifdef CONFIG_TRACING
44 void trace_init(void);
45 #else
trace_init(void)46 static inline void trace_init(void) { }
47 #endif
48
49 struct module;
50 struct ftrace_hash;
51
52 #ifdef CONFIG_FUNCTION_TRACER
53
54 extern int ftrace_enabled;
55 extern int
56 ftrace_enable_sysctl(struct ctl_table *table, int write,
57 void __user *buffer, size_t *lenp,
58 loff_t *ppos);
59
60 struct ftrace_ops;
61
62 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
63 struct ftrace_ops *op, struct pt_regs *regs);
64
65 ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops);
66
67 /*
68 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
69 * set in the flags member.
70 * CONTROL, SAVE_REGS, SAVE_REGS_IF_SUPPORTED, RECURSION_SAFE, STUB and
71 * IPMODIFY are a kind of attribute flags which can be set only before
72 * registering the ftrace_ops, and can not be modified while registered.
73 * Changing those attribute flags after regsitering ftrace_ops will
74 * cause unexpected results.
75 *
76 * ENABLED - set/unset when ftrace_ops is registered/unregistered
77 * DYNAMIC - set when ftrace_ops is registered to denote dynamically
78 * allocated ftrace_ops which need special care
79 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
80 * could be controled by following calls:
81 * ftrace_function_local_enable
82 * ftrace_function_local_disable
83 * SAVE_REGS - The ftrace_ops wants regs saved at each function called
84 * and passed to the callback. If this flag is set, but the
85 * architecture does not support passing regs
86 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
87 * ftrace_ops will fail to register, unless the next flag
88 * is set.
89 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
90 * handler can handle an arch that does not save regs
91 * (the handler tests if regs == NULL), then it can set
92 * this flag instead. It will not fail registering the ftrace_ops
93 * but, the regs field will be NULL if the arch does not support
94 * passing regs to the handler.
95 * Note, if this flag is set, the SAVE_REGS flag will automatically
96 * get set upon registering the ftrace_ops, if the arch supports it.
97 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
98 * that the call back has its own recursion protection. If it does
99 * not set this, then the ftrace infrastructure will add recursion
100 * protection for the caller.
101 * STUB - The ftrace_ops is just a place holder.
102 * INITIALIZED - The ftrace_ops has already been initialized (first use time
103 * register_ftrace_function() is called, it will initialized the ops)
104 * DELETED - The ops are being deleted, do not let them be registered again.
105 * ADDING - The ops is in the process of being added.
106 * REMOVING - The ops is in the process of being removed.
107 * MODIFYING - The ops is in the process of changing its filter functions.
108 * ALLOC_TRAMP - A dynamic trampoline was allocated by the core code.
109 * The arch specific code sets this flag when it allocated a
110 * trampoline. This lets the arch know that it can update the
111 * trampoline in case the callback function changes.
112 * The ftrace_ops trampoline can be set by the ftrace users, and
113 * in such cases the arch must not modify it. Only the arch ftrace
114 * core code should set this flag.
115 * IPMODIFY - The ops can modify the IP register. This can only be set with
116 * SAVE_REGS. If another ops with this flag set is already registered
117 * for any of the functions that this ops will be registered for, then
118 * this ops will fail to register or set_filter_ip.
119 * PID - Is affected by set_ftrace_pid (allows filtering on those pids)
120 */
121 enum {
122 FTRACE_OPS_FL_ENABLED = 1 << 0,
123 FTRACE_OPS_FL_DYNAMIC = 1 << 1,
124 FTRACE_OPS_FL_CONTROL = 1 << 2,
125 FTRACE_OPS_FL_SAVE_REGS = 1 << 3,
126 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4,
127 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5,
128 FTRACE_OPS_FL_STUB = 1 << 6,
129 FTRACE_OPS_FL_INITIALIZED = 1 << 7,
130 FTRACE_OPS_FL_DELETED = 1 << 8,
131 FTRACE_OPS_FL_ADDING = 1 << 9,
132 FTRACE_OPS_FL_REMOVING = 1 << 10,
133 FTRACE_OPS_FL_MODIFYING = 1 << 11,
134 FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 12,
135 FTRACE_OPS_FL_IPMODIFY = 1 << 13,
136 FTRACE_OPS_FL_PID = 1 << 14,
137 };
138
139 #ifdef CONFIG_DYNAMIC_FTRACE
140 /* The hash used to know what functions callbacks trace */
141 struct ftrace_ops_hash {
142 struct ftrace_hash *notrace_hash;
143 struct ftrace_hash *filter_hash;
144 struct mutex regex_lock;
145 };
146 #endif
147
148 /*
149 * Note, ftrace_ops can be referenced outside of RCU protection.
150 * (Although, for perf, the control ops prevent that). If ftrace_ops is
151 * allocated and not part of kernel core data, the unregistering of it will
152 * perform a scheduling on all CPUs to make sure that there are no more users.
153 * Depending on the load of the system that may take a bit of time.
154 *
155 * Any private data added must also take care not to be freed and if private
156 * data is added to a ftrace_ops that is in core code, the user of the
157 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
158 */
159 struct ftrace_ops {
160 ftrace_func_t func;
161 struct ftrace_ops *next;
162 unsigned long flags;
163 void *private;
164 ftrace_func_t saved_func;
165 int __percpu *disabled;
166 #ifdef CONFIG_DYNAMIC_FTRACE
167 int nr_trampolines;
168 struct ftrace_ops_hash local_hash;
169 struct ftrace_ops_hash *func_hash;
170 struct ftrace_ops_hash old_hash;
171 unsigned long trampoline;
172 unsigned long trampoline_size;
173 #endif
174 };
175
176 /*
177 * Type of the current tracing.
178 */
179 enum ftrace_tracing_type_t {
180 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
181 FTRACE_TYPE_RETURN, /* Hook the return of the function */
182 };
183
184 /* Current tracing type, default is FTRACE_TYPE_ENTER */
185 extern enum ftrace_tracing_type_t ftrace_tracing_type;
186
187 /*
188 * The ftrace_ops must be a static and should also
189 * be read_mostly. These functions do modify read_mostly variables
190 * so use them sparely. Never free an ftrace_op or modify the
191 * next pointer after it has been registered. Even after unregistering
192 * it, the next pointer may still be used internally.
193 */
194 int register_ftrace_function(struct ftrace_ops *ops);
195 int unregister_ftrace_function(struct ftrace_ops *ops);
196 void clear_ftrace_function(void);
197
198 /**
199 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
200 *
201 * This function enables tracing on current cpu by decreasing
202 * the per cpu control variable.
203 * It must be called with preemption disabled and only on ftrace_ops
204 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
205 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
206 */
ftrace_function_local_enable(struct ftrace_ops * ops)207 static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
208 {
209 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
210 return;
211
212 (*this_cpu_ptr(ops->disabled))--;
213 }
214
215 /**
216 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
217 *
218 * This function enables tracing on current cpu by decreasing
219 * the per cpu control variable.
220 * It must be called with preemption disabled and only on ftrace_ops
221 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
222 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
223 */
ftrace_function_local_disable(struct ftrace_ops * ops)224 static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
225 {
226 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
227 return;
228
229 (*this_cpu_ptr(ops->disabled))++;
230 }
231
232 /**
233 * ftrace_function_local_disabled - returns ftrace_ops disabled value
234 * on current cpu
235 *
236 * This function returns value of ftrace_ops::disabled on current cpu.
237 * It must be called with preemption disabled and only on ftrace_ops
238 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
239 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
240 */
ftrace_function_local_disabled(struct ftrace_ops * ops)241 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
242 {
243 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
244 return *this_cpu_ptr(ops->disabled);
245 }
246
247 extern void ftrace_stub(unsigned long a0, unsigned long a1,
248 struct ftrace_ops *op, struct pt_regs *regs);
249
250 #else /* !CONFIG_FUNCTION_TRACER */
251 /*
252 * (un)register_ftrace_function must be a macro since the ops parameter
253 * must not be evaluated.
254 */
255 #define register_ftrace_function(ops) ({ 0; })
256 #define unregister_ftrace_function(ops) ({ 0; })
ftrace_nr_registered_ops(void)257 static inline int ftrace_nr_registered_ops(void)
258 {
259 return 0;
260 }
clear_ftrace_function(void)261 static inline void clear_ftrace_function(void) { }
ftrace_kill(void)262 static inline void ftrace_kill(void) { }
263 #endif /* CONFIG_FUNCTION_TRACER */
264
265 #ifdef CONFIG_STACK_TRACER
266
267 #define STACK_TRACE_ENTRIES 500
268
269 struct stack_trace;
270
271 extern unsigned stack_trace_index[];
272 extern struct stack_trace stack_trace_max;
273 extern unsigned long stack_trace_max_size;
274 extern arch_spinlock_t stack_trace_max_lock;
275
276 extern int stack_tracer_enabled;
277 void stack_trace_print(void);
278 int
279 stack_trace_sysctl(struct ctl_table *table, int write,
280 void __user *buffer, size_t *lenp,
281 loff_t *ppos);
282 #endif
283
284 struct ftrace_func_command {
285 struct list_head list;
286 char *name;
287 int (*func)(struct ftrace_hash *hash,
288 char *func, char *cmd,
289 char *params, int enable);
290 };
291
292 #ifdef CONFIG_DYNAMIC_FTRACE
293
294 int ftrace_arch_code_modify_prepare(void);
295 int ftrace_arch_code_modify_post_process(void);
296
297 struct dyn_ftrace;
298
299 void ftrace_bug(int err, struct dyn_ftrace *rec);
300
301 struct seq_file;
302
303 struct ftrace_probe_ops {
304 void (*func)(unsigned long ip,
305 unsigned long parent_ip,
306 void **data);
307 int (*init)(struct ftrace_probe_ops *ops,
308 unsigned long ip, void **data);
309 void (*free)(struct ftrace_probe_ops *ops,
310 unsigned long ip, void **data);
311 int (*print)(struct seq_file *m,
312 unsigned long ip,
313 struct ftrace_probe_ops *ops,
314 void *data);
315 };
316
317 extern int
318 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
319 void *data);
320 extern void
321 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
322 void *data);
323 extern void
324 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
325 extern void unregister_ftrace_function_probe_all(char *glob);
326
327 extern int ftrace_text_reserved(const void *start, const void *end);
328
329 extern int ftrace_nr_registered_ops(void);
330
331 bool is_ftrace_trampoline(unsigned long addr);
332
333 /*
334 * The dyn_ftrace record's flags field is split into two parts.
335 * the first part which is '0-FTRACE_REF_MAX' is a counter of
336 * the number of callbacks that have registered the function that
337 * the dyn_ftrace descriptor represents.
338 *
339 * The second part is a mask:
340 * ENABLED - the function is being traced
341 * REGS - the record wants the function to save regs
342 * REGS_EN - the function is set up to save regs.
343 * IPMODIFY - the record allows for the IP address to be changed.
344 *
345 * When a new ftrace_ops is registered and wants a function to save
346 * pt_regs, the rec->flag REGS is set. When the function has been
347 * set up to save regs, the REG_EN flag is set. Once a function
348 * starts saving regs it will do so until all ftrace_ops are removed
349 * from tracing that function.
350 */
351 enum {
352 FTRACE_FL_ENABLED = (1UL << 31),
353 FTRACE_FL_REGS = (1UL << 30),
354 FTRACE_FL_REGS_EN = (1UL << 29),
355 FTRACE_FL_TRAMP = (1UL << 28),
356 FTRACE_FL_TRAMP_EN = (1UL << 27),
357 FTRACE_FL_IPMODIFY = (1UL << 26),
358 };
359
360 #define FTRACE_REF_MAX_SHIFT 26
361 #define FTRACE_FL_BITS 6
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
368 struct dyn_ftrace {
369 unsigned long ip; /* address of mcount call-site */
370 unsigned long flags;
371 struct dyn_arch_ftrace arch;
372 };
373
374 int ftrace_force_update(void);
375 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
376 int remove, int reset);
377 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
378 int len, int reset);
379 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
380 int len, int reset);
381 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
382 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
383 void ftrace_free_filter(struct ftrace_ops *ops);
384
385 int register_ftrace_command(struct ftrace_func_command *cmd);
386 int unregister_ftrace_command(struct ftrace_func_command *cmd);
387
388 enum {
389 FTRACE_UPDATE_CALLS = (1 << 0),
390 FTRACE_DISABLE_CALLS = (1 << 1),
391 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
392 FTRACE_START_FUNC_RET = (1 << 3),
393 FTRACE_STOP_FUNC_RET = (1 << 4),
394 };
395
396 /*
397 * The FTRACE_UPDATE_* enum is used to pass information back
398 * from the ftrace_update_record() and ftrace_test_record()
399 * functions. These are called by the code update routines
400 * to find out what is to be done for a given function.
401 *
402 * IGNORE - The function is already what we want it to be
403 * MAKE_CALL - Start tracing the function
404 * MODIFY_CALL - Stop saving regs for the function
405 * MAKE_NOP - Stop tracing the function
406 */
407 enum {
408 FTRACE_UPDATE_IGNORE,
409 FTRACE_UPDATE_MAKE_CALL,
410 FTRACE_UPDATE_MODIFY_CALL,
411 FTRACE_UPDATE_MAKE_NOP,
412 };
413
414 enum {
415 FTRACE_ITER_FILTER = (1 << 0),
416 FTRACE_ITER_NOTRACE = (1 << 1),
417 FTRACE_ITER_PRINTALL = (1 << 2),
418 FTRACE_ITER_DO_HASH = (1 << 3),
419 FTRACE_ITER_HASH = (1 << 4),
420 FTRACE_ITER_ENABLED = (1 << 5),
421 };
422
423 void arch_ftrace_update_code(int command);
424
425 struct ftrace_rec_iter;
426
427 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
428 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
429 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
430
431 #define for_ftrace_rec_iter(iter) \
432 for (iter = ftrace_rec_iter_start(); \
433 iter; \
434 iter = ftrace_rec_iter_next(iter))
435
436
437 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
438 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
439 void ftrace_run_stop_machine(int command);
440 unsigned long ftrace_location(unsigned long ip);
441 unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);
442 unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);
443
444 extern ftrace_func_t ftrace_trace_function;
445
446 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
447 struct inode *inode, struct file *file);
448 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
449 size_t cnt, loff_t *ppos);
450 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
451 size_t cnt, loff_t *ppos);
452 int ftrace_regex_release(struct inode *inode, struct file *file);
453
454 void __init
455 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
456
457 /* defined in arch */
458 extern int ftrace_ip_converted(unsigned long ip);
459 extern int ftrace_dyn_arch_init(void);
460 extern void ftrace_replace_code(int enable);
461 extern int ftrace_update_ftrace_func(ftrace_func_t func);
462 extern void ftrace_caller(void);
463 extern void ftrace_regs_caller(void);
464 extern void ftrace_call(void);
465 extern void ftrace_regs_call(void);
466 extern void mcount_call(void);
467
468 void ftrace_modify_all_code(int command);
469
470 #ifndef FTRACE_ADDR
471 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
472 #endif
473
474 #ifndef FTRACE_GRAPH_ADDR
475 #define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
476 #endif
477
478 #ifndef FTRACE_REGS_ADDR
479 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
480 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
481 #else
482 # define FTRACE_REGS_ADDR FTRACE_ADDR
483 #endif
484 #endif
485
486 /*
487 * If an arch would like functions that are only traced
488 * by the function graph tracer to jump directly to its own
489 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
490 * to be that address to jump to.
491 */
492 #ifndef FTRACE_GRAPH_TRAMP_ADDR
493 #define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
494 #endif
495
496 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
497 extern void ftrace_graph_caller(void);
498 extern int ftrace_enable_ftrace_graph_caller(void);
499 extern int ftrace_disable_ftrace_graph_caller(void);
500 #else
ftrace_enable_ftrace_graph_caller(void)501 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
ftrace_disable_ftrace_graph_caller(void)502 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
503 #endif
504
505 /**
506 * ftrace_make_nop - convert code into nop
507 * @mod: module structure if called by module load initialization
508 * @rec: the mcount call site record
509 * @addr: the address that the call site should be calling
510 *
511 * This is a very sensitive operation and great care needs
512 * to be taken by the arch. The operation should carefully
513 * read the location, check to see if what is read is indeed
514 * what we expect it to be, and then on success of the compare,
515 * it should write to the location.
516 *
517 * The code segment at @rec->ip should be a caller to @addr
518 *
519 * Return must be:
520 * 0 on success
521 * -EFAULT on error reading the location
522 * -EINVAL on a failed compare of the contents
523 * -EPERM on error writing to the location
524 * Any other value will be considered a failure.
525 */
526 extern int ftrace_make_nop(struct module *mod,
527 struct dyn_ftrace *rec, unsigned long addr);
528
529 /**
530 * ftrace_make_call - convert a nop call site into a call to addr
531 * @rec: the mcount call site record
532 * @addr: the address that the call site should call
533 *
534 * This is a very sensitive operation and great care needs
535 * to be taken by the arch. The operation should carefully
536 * read the location, check to see if what is read is indeed
537 * what we expect it to be, and then on success of the compare,
538 * it should write to the location.
539 *
540 * The code segment at @rec->ip should be a nop
541 *
542 * Return must be:
543 * 0 on success
544 * -EFAULT on error reading the location
545 * -EINVAL on a failed compare of the contents
546 * -EPERM on error writing to the location
547 * Any other value will be considered a failure.
548 */
549 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
550
551 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
552 /**
553 * ftrace_modify_call - convert from one addr to another (no nop)
554 * @rec: the mcount call site record
555 * @old_addr: the address expected to be currently called to
556 * @addr: the address to change to
557 *
558 * This is a very sensitive operation and great care needs
559 * to be taken by the arch. The operation should carefully
560 * read the location, check to see if what is read is indeed
561 * what we expect it to be, and then on success of the compare,
562 * it should write to the location.
563 *
564 * The code segment at @rec->ip should be a caller to @old_addr
565 *
566 * Return must be:
567 * 0 on success
568 * -EFAULT on error reading the location
569 * -EINVAL on a failed compare of the contents
570 * -EPERM on error writing to the location
571 * Any other value will be considered a failure.
572 */
573 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
574 unsigned long addr);
575 #else
576 /* Should never be called */
ftrace_modify_call(struct dyn_ftrace * rec,unsigned long old_addr,unsigned long addr)577 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
578 unsigned long addr)
579 {
580 return -EINVAL;
581 }
582 #endif
583
584 /* May be defined in arch */
585 extern int ftrace_arch_read_dyn_info(char *buf, int size);
586
587 extern int skip_trace(unsigned long ip);
588 extern void ftrace_module_init(struct module *mod);
589 extern void ftrace_release_mod(struct module *mod);
590
591 extern void ftrace_disable_daemon(void);
592 extern void ftrace_enable_daemon(void);
593 #else /* CONFIG_DYNAMIC_FTRACE */
skip_trace(unsigned long ip)594 static inline int skip_trace(unsigned long ip) { return 0; }
ftrace_force_update(void)595 static inline int ftrace_force_update(void) { return 0; }
ftrace_disable_daemon(void)596 static inline void ftrace_disable_daemon(void) { }
ftrace_enable_daemon(void)597 static inline void ftrace_enable_daemon(void) { }
ftrace_release_mod(struct module * mod)598 static inline void ftrace_release_mod(struct module *mod) {}
ftrace_module_init(struct module * mod)599 static inline void ftrace_module_init(struct module *mod) {}
register_ftrace_command(struct ftrace_func_command * cmd)600 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
601 {
602 return -EINVAL;
603 }
unregister_ftrace_command(char * cmd_name)604 static inline __init int unregister_ftrace_command(char *cmd_name)
605 {
606 return -EINVAL;
607 }
ftrace_text_reserved(const void * start,const void * end)608 static inline int ftrace_text_reserved(const void *start, const void *end)
609 {
610 return 0;
611 }
ftrace_location(unsigned long ip)612 static inline unsigned long ftrace_location(unsigned long ip)
613 {
614 return 0;
615 }
616
617 /*
618 * Again users of functions that have ftrace_ops may not
619 * have them defined when ftrace is not enabled, but these
620 * functions may still be called. Use a macro instead of inline.
621 */
622 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
623 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
624 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
625 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
626 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
627 #define ftrace_free_filter(ops) do { } while (0)
628
ftrace_filter_write(struct file * file,const char __user * ubuf,size_t cnt,loff_t * ppos)629 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
630 size_t cnt, loff_t *ppos) { return -ENODEV; }
ftrace_notrace_write(struct file * file,const char __user * ubuf,size_t cnt,loff_t * ppos)631 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
632 size_t cnt, loff_t *ppos) { return -ENODEV; }
633 static inline int
ftrace_regex_release(struct inode * inode,struct file * file)634 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
635
is_ftrace_trampoline(unsigned long addr)636 static inline bool is_ftrace_trampoline(unsigned long addr)
637 {
638 return false;
639 }
640 #endif /* CONFIG_DYNAMIC_FTRACE */
641
642 /* totally disable ftrace - can not re-enable after this */
643 void ftrace_kill(void);
644
tracer_disable(void)645 static inline void tracer_disable(void)
646 {
647 #ifdef CONFIG_FUNCTION_TRACER
648 ftrace_enabled = 0;
649 #endif
650 }
651
652 /*
653 * Ftrace disable/restore without lock. Some synchronization mechanism
654 * must be used to prevent ftrace_enabled to be changed between
655 * disable/restore.
656 */
__ftrace_enabled_save(void)657 static inline int __ftrace_enabled_save(void)
658 {
659 #ifdef CONFIG_FUNCTION_TRACER
660 int saved_ftrace_enabled = ftrace_enabled;
661 ftrace_enabled = 0;
662 return saved_ftrace_enabled;
663 #else
664 return 0;
665 #endif
666 }
667
__ftrace_enabled_restore(int enabled)668 static inline void __ftrace_enabled_restore(int enabled)
669 {
670 #ifdef CONFIG_FUNCTION_TRACER
671 ftrace_enabled = enabled;
672 #endif
673 }
674
675 /* All archs should have this, but we define it for consistency */
676 #ifndef ftrace_return_address0
677 # define ftrace_return_address0 __builtin_return_address(0)
678 #endif
679
680 /* Archs may use other ways for ADDR1 and beyond */
681 #ifndef ftrace_return_address
682 # ifdef CONFIG_FRAME_POINTER
683 # define ftrace_return_address(n) __builtin_return_address(n)
684 # else
685 # define ftrace_return_address(n) 0UL
686 # endif
687 #endif
688
689 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0)
690 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1))
691 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2))
692 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3))
693 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4))
694 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
695 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
696
697 #ifdef CONFIG_IRQSOFF_TRACER
698 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
699 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
700 #else
time_hardirqs_on(unsigned long a0,unsigned long a1)701 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
time_hardirqs_off(unsigned long a0,unsigned long a1)702 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
703 #endif
704
705 #ifdef CONFIG_PREEMPT_TRACER
706 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
707 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
708 #else
709 /*
710 * Use defines instead of static inlines because some arches will make code out
711 * of the CALLER_ADDR, when we really want these to be a real nop.
712 */
713 # define trace_preempt_on(a0, a1) do { } while (0)
714 # define trace_preempt_off(a0, a1) do { } while (0)
715 #endif
716
717 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
718 extern void ftrace_init(void);
719 #else
ftrace_init(void)720 static inline void ftrace_init(void) { }
721 #endif
722
723 /*
724 * Structure that defines an entry function trace.
725 */
726 struct ftrace_graph_ent {
727 unsigned long func; /* Current function */
728 int depth;
729 };
730
731 /*
732 * Structure that defines a return function trace.
733 */
734 struct ftrace_graph_ret {
735 unsigned long func; /* Current function */
736 unsigned long long calltime;
737 unsigned long long rettime;
738 /* Number of functions that overran the depth limit for current task */
739 unsigned long overrun;
740 int depth;
741 };
742
743 /* Type of the callback handlers for tracing function graph*/
744 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
745 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
746
747 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
748
749 /* for init task */
750 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
751
752 /*
753 * Stack of return addresses for functions
754 * of a thread.
755 * Used in struct thread_info
756 */
757 struct ftrace_ret_stack {
758 unsigned long ret;
759 unsigned long func;
760 unsigned long long calltime;
761 unsigned long long subtime;
762 unsigned long fp;
763 };
764
765 /*
766 * Primary handler of a function return.
767 * It relays on ftrace_return_to_handler.
768 * Defined in entry_32/64.S
769 */
770 extern void return_to_handler(void);
771
772 extern int
773 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
774 unsigned long frame_pointer);
775
776 /*
777 * Sometimes we don't want to trace a function with the function
778 * graph tracer but we want them to keep traced by the usual function
779 * tracer if the function graph tracer is not configured.
780 */
781 #define __notrace_funcgraph notrace
782
783 /*
784 * We want to which function is an entrypoint of a hardirq.
785 * That will help us to put a signal on output.
786 */
787 #define __irq_entry __attribute__((__section__(".irqentry.text")))
788
789 /* Limits of hardirq entrypoints */
790 extern char __irqentry_text_start[];
791 extern char __irqentry_text_end[];
792
793 #define FTRACE_NOTRACE_DEPTH 65536
794 #define FTRACE_RETFUNC_DEPTH 50
795 #define FTRACE_RETSTACK_ALLOC_SIZE 32
796 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
797 trace_func_graph_ent_t entryfunc);
798
799 extern bool ftrace_graph_is_dead(void);
800 extern void ftrace_graph_stop(void);
801
802 /* The current handlers in use */
803 extern trace_func_graph_ret_t ftrace_graph_return;
804 extern trace_func_graph_ent_t ftrace_graph_entry;
805
806 extern void unregister_ftrace_graph(void);
807
808 extern void ftrace_graph_init_task(struct task_struct *t);
809 extern void ftrace_graph_exit_task(struct task_struct *t);
810 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
811
task_curr_ret_stack(struct task_struct * t)812 static inline int task_curr_ret_stack(struct task_struct *t)
813 {
814 return t->curr_ret_stack;
815 }
816
pause_graph_tracing(void)817 static inline void pause_graph_tracing(void)
818 {
819 atomic_inc(¤t->tracing_graph_pause);
820 }
821
unpause_graph_tracing(void)822 static inline void unpause_graph_tracing(void)
823 {
824 atomic_dec(¤t->tracing_graph_pause);
825 }
826 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
827
828 #define __notrace_funcgraph
829 #define __irq_entry
830 #define INIT_FTRACE_GRAPH
831
ftrace_graph_init_task(struct task_struct * t)832 static inline void ftrace_graph_init_task(struct task_struct *t) { }
ftrace_graph_exit_task(struct task_struct * t)833 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
ftrace_graph_init_idle_task(struct task_struct * t,int cpu)834 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
835
register_ftrace_graph(trace_func_graph_ret_t retfunc,trace_func_graph_ent_t entryfunc)836 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
837 trace_func_graph_ent_t entryfunc)
838 {
839 return -1;
840 }
unregister_ftrace_graph(void)841 static inline void unregister_ftrace_graph(void) { }
842
task_curr_ret_stack(struct task_struct * tsk)843 static inline int task_curr_ret_stack(struct task_struct *tsk)
844 {
845 return -1;
846 }
847
pause_graph_tracing(void)848 static inline void pause_graph_tracing(void) { }
unpause_graph_tracing(void)849 static inline void unpause_graph_tracing(void) { }
850 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
851
852 #ifdef CONFIG_TRACING
853
854 /* flags for current->trace */
855 enum {
856 TSK_TRACE_FL_TRACE_BIT = 0,
857 TSK_TRACE_FL_GRAPH_BIT = 1,
858 };
859 enum {
860 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
861 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
862 };
863
set_tsk_trace_trace(struct task_struct * tsk)864 static inline void set_tsk_trace_trace(struct task_struct *tsk)
865 {
866 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
867 }
868
clear_tsk_trace_trace(struct task_struct * tsk)869 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
870 {
871 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
872 }
873
test_tsk_trace_trace(struct task_struct * tsk)874 static inline int test_tsk_trace_trace(struct task_struct *tsk)
875 {
876 return tsk->trace & TSK_TRACE_FL_TRACE;
877 }
878
set_tsk_trace_graph(struct task_struct * tsk)879 static inline void set_tsk_trace_graph(struct task_struct *tsk)
880 {
881 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
882 }
883
clear_tsk_trace_graph(struct task_struct * tsk)884 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
885 {
886 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
887 }
888
test_tsk_trace_graph(struct task_struct * tsk)889 static inline int test_tsk_trace_graph(struct task_struct *tsk)
890 {
891 return tsk->trace & TSK_TRACE_FL_GRAPH;
892 }
893
894 enum ftrace_dump_mode;
895
896 extern enum ftrace_dump_mode ftrace_dump_on_oops;
897 extern int tracepoint_printk;
898
899 extern void disable_trace_on_warning(void);
900 extern int __disable_trace_on_warning;
901
902 #ifdef CONFIG_PREEMPT
903 #define INIT_TRACE_RECURSION .trace_recursion = 0,
904 #endif
905
906 #else /* CONFIG_TRACING */
disable_trace_on_warning(void)907 static inline void disable_trace_on_warning(void) { }
908 #endif /* CONFIG_TRACING */
909
910 #ifndef INIT_TRACE_RECURSION
911 #define INIT_TRACE_RECURSION
912 #endif
913
914 #ifdef CONFIG_FTRACE_SYSCALLS
915
916 unsigned long arch_syscall_addr(int nr);
917
918 #endif /* CONFIG_FTRACE_SYSCALLS */
919
920 #endif /* _LINUX_FTRACE_H */
921