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/ktime.h>
14 #include <linux/sched.h>
15 #include <linux/types.h>
16 #include <linux/init.h>
17 #include <linux/fs.h>
18
19 #include <asm/ftrace.h>
20
21 struct module;
22 struct ftrace_hash;
23
24 #ifdef CONFIG_FUNCTION_TRACER
25
26 extern int ftrace_enabled;
27 extern int
28 ftrace_enable_sysctl(struct ctl_table *table, int write,
29 void __user *buffer, size_t *lenp,
30 loff_t *ppos);
31
32 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
33
34 enum {
35 FTRACE_OPS_FL_ENABLED = 1 << 0,
36 FTRACE_OPS_FL_GLOBAL = 1 << 1,
37 FTRACE_OPS_FL_DYNAMIC = 1 << 2,
38 };
39
40 struct ftrace_ops {
41 ftrace_func_t func;
42 struct ftrace_ops *next;
43 unsigned long flags;
44 #ifdef CONFIG_DYNAMIC_FTRACE
45 struct ftrace_hash *notrace_hash;
46 struct ftrace_hash *filter_hash;
47 #endif
48 };
49
50 extern int function_trace_stop;
51
52 /*
53 * Type of the current tracing.
54 */
55 enum ftrace_tracing_type_t {
56 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
57 FTRACE_TYPE_RETURN, /* Hook the return of the function */
58 };
59
60 /* Current tracing type, default is FTRACE_TYPE_ENTER */
61 extern enum ftrace_tracing_type_t ftrace_tracing_type;
62
63 /**
64 * ftrace_stop - stop function tracer.
65 *
66 * A quick way to stop the function tracer. Note this an on off switch,
67 * it is not something that is recursive like preempt_disable.
68 * This does not disable the calling of mcount, it only stops the
69 * calling of functions from mcount.
70 */
ftrace_stop(void)71 static inline void ftrace_stop(void)
72 {
73 function_trace_stop = 1;
74 }
75
76 /**
77 * ftrace_start - start the function tracer.
78 *
79 * This function is the inverse of ftrace_stop. This does not enable
80 * the function tracing if the function tracer is disabled. This only
81 * sets the function tracer flag to continue calling the functions
82 * from mcount.
83 */
ftrace_start(void)84 static inline void ftrace_start(void)
85 {
86 function_trace_stop = 0;
87 }
88
89 /*
90 * The ftrace_ops must be a static and should also
91 * be read_mostly. These functions do modify read_mostly variables
92 * so use them sparely. Never free an ftrace_op or modify the
93 * next pointer after it has been registered. Even after unregistering
94 * it, the next pointer may still be used internally.
95 */
96 int register_ftrace_function(struct ftrace_ops *ops);
97 int unregister_ftrace_function(struct ftrace_ops *ops);
98 void clear_ftrace_function(void);
99
100 extern void ftrace_stub(unsigned long a0, unsigned long a1);
101
102 #else /* !CONFIG_FUNCTION_TRACER */
103 /*
104 * (un)register_ftrace_function must be a macro since the ops parameter
105 * must not be evaluated.
106 */
107 #define register_ftrace_function(ops) ({ 0; })
108 #define unregister_ftrace_function(ops) ({ 0; })
clear_ftrace_function(void)109 static inline void clear_ftrace_function(void) { }
ftrace_kill(void)110 static inline void ftrace_kill(void) { }
ftrace_stop(void)111 static inline void ftrace_stop(void) { }
ftrace_start(void)112 static inline void ftrace_start(void) { }
113 #endif /* CONFIG_FUNCTION_TRACER */
114
115 #ifdef CONFIG_STACK_TRACER
116 extern int stack_tracer_enabled;
117 int
118 stack_trace_sysctl(struct ctl_table *table, int write,
119 void __user *buffer, size_t *lenp,
120 loff_t *ppos);
121 #endif
122
123 struct ftrace_func_command {
124 struct list_head list;
125 char *name;
126 int (*func)(struct ftrace_hash *hash,
127 char *func, char *cmd,
128 char *params, int enable);
129 };
130
131 #ifdef CONFIG_DYNAMIC_FTRACE
132
133 int ftrace_arch_code_modify_prepare(void);
134 int ftrace_arch_code_modify_post_process(void);
135
136 void ftrace_bug(int err, unsigned long ip);
137
138 struct seq_file;
139
140 struct ftrace_probe_ops {
141 void (*func)(unsigned long ip,
142 unsigned long parent_ip,
143 void **data);
144 int (*callback)(unsigned long ip, void **data);
145 void (*free)(void **data);
146 int (*print)(struct seq_file *m,
147 unsigned long ip,
148 struct ftrace_probe_ops *ops,
149 void *data);
150 };
151
152 extern int
153 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
154 void *data);
155 extern void
156 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
157 void *data);
158 extern void
159 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
160 extern void unregister_ftrace_function_probe_all(char *glob);
161
162 extern int ftrace_text_reserved(void *start, void *end);
163
164 enum {
165 FTRACE_FL_ENABLED = (1 << 30),
166 };
167
168 #define FTRACE_FL_MASK (0x3UL << 30)
169 #define FTRACE_REF_MAX ((1 << 30) - 1)
170
171 struct dyn_ftrace {
172 union {
173 unsigned long ip; /* address of mcount call-site */
174 struct dyn_ftrace *freelist;
175 };
176 unsigned long flags;
177 struct dyn_arch_ftrace arch;
178 };
179
180 int ftrace_force_update(void);
181 void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
182 int len, int reset);
183 void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
184 int len, int reset);
185 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
186 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
187
188 int register_ftrace_command(struct ftrace_func_command *cmd);
189 int unregister_ftrace_command(struct ftrace_func_command *cmd);
190
191 enum {
192 FTRACE_UPDATE_CALLS = (1 << 0),
193 FTRACE_DISABLE_CALLS = (1 << 1),
194 FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
195 FTRACE_START_FUNC_RET = (1 << 3),
196 FTRACE_STOP_FUNC_RET = (1 << 4),
197 };
198
199 enum {
200 FTRACE_UPDATE_IGNORE,
201 FTRACE_UPDATE_MAKE_CALL,
202 FTRACE_UPDATE_MAKE_NOP,
203 };
204
205 enum {
206 FTRACE_ITER_FILTER = (1 << 0),
207 FTRACE_ITER_NOTRACE = (1 << 1),
208 FTRACE_ITER_PRINTALL = (1 << 2),
209 FTRACE_ITER_DO_HASH = (1 << 3),
210 FTRACE_ITER_HASH = (1 << 4),
211 FTRACE_ITER_ENABLED = (1 << 5),
212 };
213
214 void arch_ftrace_update_code(int command);
215
216 struct ftrace_rec_iter;
217
218 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
219 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
220 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
221
222 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
223 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
224 void ftrace_run_stop_machine(int command);
225 int ftrace_location(unsigned long ip);
226
227 extern ftrace_func_t ftrace_trace_function;
228
229 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
230 struct inode *inode, struct file *file);
231 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
232 size_t cnt, loff_t *ppos);
233 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
234 size_t cnt, loff_t *ppos);
235 loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin);
236 int ftrace_regex_release(struct inode *inode, struct file *file);
237
238 void __init
239 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
240
241 /* defined in arch */
242 extern int ftrace_ip_converted(unsigned long ip);
243 extern int ftrace_dyn_arch_init(void *data);
244 extern int ftrace_update_ftrace_func(ftrace_func_t func);
245 extern void ftrace_caller(void);
246 extern void ftrace_call(void);
247 extern void mcount_call(void);
248
249 #ifndef FTRACE_ADDR
250 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
251 #endif
252 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
253 extern void ftrace_graph_caller(void);
254 extern int ftrace_enable_ftrace_graph_caller(void);
255 extern int ftrace_disable_ftrace_graph_caller(void);
256 #else
ftrace_enable_ftrace_graph_caller(void)257 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
ftrace_disable_ftrace_graph_caller(void)258 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
259 #endif
260
261 /**
262 * ftrace_make_nop - convert code into nop
263 * @mod: module structure if called by module load initialization
264 * @rec: the mcount call site record
265 * @addr: the address that the call site should be calling
266 *
267 * This is a very sensitive operation and great care needs
268 * to be taken by the arch. The operation should carefully
269 * read the location, check to see if what is read is indeed
270 * what we expect it to be, and then on success of the compare,
271 * it should write to the location.
272 *
273 * The code segment at @rec->ip should be a caller to @addr
274 *
275 * Return must be:
276 * 0 on success
277 * -EFAULT on error reading the location
278 * -EINVAL on a failed compare of the contents
279 * -EPERM on error writing to the location
280 * Any other value will be considered a failure.
281 */
282 extern int ftrace_make_nop(struct module *mod,
283 struct dyn_ftrace *rec, unsigned long addr);
284
285 /**
286 * ftrace_make_call - convert a nop call site into a call to addr
287 * @rec: the mcount call site record
288 * @addr: the address that the call site should call
289 *
290 * This is a very sensitive operation and great care needs
291 * to be taken by the arch. The operation should carefully
292 * read the location, check to see if what is read is indeed
293 * what we expect it to be, and then on success of the compare,
294 * it should write to the location.
295 *
296 * The code segment at @rec->ip should be a nop
297 *
298 * Return must be:
299 * 0 on success
300 * -EFAULT on error reading the location
301 * -EINVAL on a failed compare of the contents
302 * -EPERM on error writing to the location
303 * Any other value will be considered a failure.
304 */
305 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
306
307 /* May be defined in arch */
308 extern int ftrace_arch_read_dyn_info(char *buf, int size);
309
310 extern int skip_trace(unsigned long ip);
311
312 extern void ftrace_disable_daemon(void);
313 extern void ftrace_enable_daemon(void);
314 #else
skip_trace(unsigned long ip)315 static inline int skip_trace(unsigned long ip) { return 0; }
ftrace_force_update(void)316 static inline int ftrace_force_update(void) { return 0; }
ftrace_set_filter(unsigned char * buf,int len,int reset)317 static inline void ftrace_set_filter(unsigned char *buf, int len, int reset)
318 {
319 }
ftrace_disable_daemon(void)320 static inline void ftrace_disable_daemon(void) { }
ftrace_enable_daemon(void)321 static inline void ftrace_enable_daemon(void) { }
ftrace_release_mod(struct module * mod)322 static inline void ftrace_release_mod(struct module *mod) {}
register_ftrace_command(struct ftrace_func_command * cmd)323 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
324 {
325 return -EINVAL;
326 }
unregister_ftrace_command(char * cmd_name)327 static inline int unregister_ftrace_command(char *cmd_name)
328 {
329 return -EINVAL;
330 }
ftrace_text_reserved(void * start,void * end)331 static inline int ftrace_text_reserved(void *start, void *end)
332 {
333 return 0;
334 }
335
336 /*
337 * Again users of functions that have ftrace_ops may not
338 * have them defined when ftrace is not enabled, but these
339 * functions may still be called. Use a macro instead of inline.
340 */
341 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
342 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
343
ftrace_filter_write(struct file * file,const char __user * ubuf,size_t cnt,loff_t * ppos)344 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
345 size_t cnt, loff_t *ppos) { return -ENODEV; }
ftrace_notrace_write(struct file * file,const char __user * ubuf,size_t cnt,loff_t * ppos)346 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
347 size_t cnt, loff_t *ppos) { return -ENODEV; }
ftrace_regex_lseek(struct file * file,loff_t offset,int origin)348 static inline loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
349 {
350 return -ENODEV;
351 }
352 static inline int
ftrace_regex_release(struct inode * inode,struct file * file)353 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
354 #endif /* CONFIG_DYNAMIC_FTRACE */
355
356 /* totally disable ftrace - can not re-enable after this */
357 void ftrace_kill(void);
358
tracer_disable(void)359 static inline void tracer_disable(void)
360 {
361 #ifdef CONFIG_FUNCTION_TRACER
362 ftrace_enabled = 0;
363 #endif
364 }
365
366 /*
367 * Ftrace disable/restore without lock. Some synchronization mechanism
368 * must be used to prevent ftrace_enabled to be changed between
369 * disable/restore.
370 */
__ftrace_enabled_save(void)371 static inline int __ftrace_enabled_save(void)
372 {
373 #ifdef CONFIG_FUNCTION_TRACER
374 int saved_ftrace_enabled = ftrace_enabled;
375 ftrace_enabled = 0;
376 return saved_ftrace_enabled;
377 #else
378 return 0;
379 #endif
380 }
381
__ftrace_enabled_restore(int enabled)382 static inline void __ftrace_enabled_restore(int enabled)
383 {
384 #ifdef CONFIG_FUNCTION_TRACER
385 ftrace_enabled = enabled;
386 #endif
387 }
388
389 #ifndef HAVE_ARCH_CALLER_ADDR
390 # ifdef CONFIG_FRAME_POINTER
391 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
392 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
393 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
394 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
395 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
396 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
397 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
398 # else
399 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
400 # define CALLER_ADDR1 0UL
401 # define CALLER_ADDR2 0UL
402 # define CALLER_ADDR3 0UL
403 # define CALLER_ADDR4 0UL
404 # define CALLER_ADDR5 0UL
405 # define CALLER_ADDR6 0UL
406 # endif
407 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
408
409 #ifdef CONFIG_IRQSOFF_TRACER
410 extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
411 extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
412 #else
time_hardirqs_on(unsigned long a0,unsigned long a1)413 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
time_hardirqs_off(unsigned long a0,unsigned long a1)414 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
415 #endif
416
417 #ifdef CONFIG_PREEMPT_TRACER
418 extern void trace_preempt_on(unsigned long a0, unsigned long a1);
419 extern void trace_preempt_off(unsigned long a0, unsigned long a1);
420 #else
trace_preempt_on(unsigned long a0,unsigned long a1)421 static inline void trace_preempt_on(unsigned long a0, unsigned long a1) { }
trace_preempt_off(unsigned long a0,unsigned long a1)422 static inline void trace_preempt_off(unsigned long a0, unsigned long a1) { }
423 #endif
424
425 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
426 extern void ftrace_init(void);
427 #else
ftrace_init(void)428 static inline void ftrace_init(void) { }
429 #endif
430
431 /*
432 * Structure that defines an entry function trace.
433 */
434 struct ftrace_graph_ent {
435 unsigned long func; /* Current function */
436 int depth;
437 };
438
439 /*
440 * Structure that defines a return function trace.
441 */
442 struct ftrace_graph_ret {
443 unsigned long func; /* Current function */
444 unsigned long long calltime;
445 unsigned long long rettime;
446 /* Number of functions that overran the depth limit for current task */
447 unsigned long overrun;
448 int depth;
449 };
450
451 /* Type of the callback handlers for tracing function graph*/
452 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
453 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
454
455 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
456
457 /* for init task */
458 #define INIT_FTRACE_GRAPH .ret_stack = NULL,
459
460 /*
461 * Stack of return addresses for functions
462 * of a thread.
463 * Used in struct thread_info
464 */
465 struct ftrace_ret_stack {
466 unsigned long ret;
467 unsigned long func;
468 unsigned long long calltime;
469 unsigned long long subtime;
470 unsigned long fp;
471 };
472
473 /*
474 * Primary handler of a function return.
475 * It relays on ftrace_return_to_handler.
476 * Defined in entry_32/64.S
477 */
478 extern void return_to_handler(void);
479
480 extern int
481 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
482 unsigned long frame_pointer);
483
484 /*
485 * Sometimes we don't want to trace a function with the function
486 * graph tracer but we want them to keep traced by the usual function
487 * tracer if the function graph tracer is not configured.
488 */
489 #define __notrace_funcgraph notrace
490
491 /*
492 * We want to which function is an entrypoint of a hardirq.
493 * That will help us to put a signal on output.
494 */
495 #define __irq_entry __attribute__((__section__(".irqentry.text")))
496
497 /* Limits of hardirq entrypoints */
498 extern char __irqentry_text_start[];
499 extern char __irqentry_text_end[];
500
501 #define FTRACE_RETFUNC_DEPTH 50
502 #define FTRACE_RETSTACK_ALLOC_SIZE 32
503 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
504 trace_func_graph_ent_t entryfunc);
505
506 extern void ftrace_graph_stop(void);
507
508 /* The current handlers in use */
509 extern trace_func_graph_ret_t ftrace_graph_return;
510 extern trace_func_graph_ent_t ftrace_graph_entry;
511
512 extern void unregister_ftrace_graph(void);
513
514 extern void ftrace_graph_init_task(struct task_struct *t);
515 extern void ftrace_graph_exit_task(struct task_struct *t);
516 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
517
task_curr_ret_stack(struct task_struct * t)518 static inline int task_curr_ret_stack(struct task_struct *t)
519 {
520 return t->curr_ret_stack;
521 }
522
pause_graph_tracing(void)523 static inline void pause_graph_tracing(void)
524 {
525 atomic_inc(¤t->tracing_graph_pause);
526 }
527
unpause_graph_tracing(void)528 static inline void unpause_graph_tracing(void)
529 {
530 atomic_dec(¤t->tracing_graph_pause);
531 }
532 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
533
534 #define __notrace_funcgraph
535 #define __irq_entry
536 #define INIT_FTRACE_GRAPH
537
ftrace_graph_init_task(struct task_struct * t)538 static inline void ftrace_graph_init_task(struct task_struct *t) { }
ftrace_graph_exit_task(struct task_struct * t)539 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
ftrace_graph_init_idle_task(struct task_struct * t,int cpu)540 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
541
register_ftrace_graph(trace_func_graph_ret_t retfunc,trace_func_graph_ent_t entryfunc)542 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
543 trace_func_graph_ent_t entryfunc)
544 {
545 return -1;
546 }
unregister_ftrace_graph(void)547 static inline void unregister_ftrace_graph(void) { }
548
task_curr_ret_stack(struct task_struct * tsk)549 static inline int task_curr_ret_stack(struct task_struct *tsk)
550 {
551 return -1;
552 }
553
pause_graph_tracing(void)554 static inline void pause_graph_tracing(void) { }
unpause_graph_tracing(void)555 static inline void unpause_graph_tracing(void) { }
556 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
557
558 #ifdef CONFIG_TRACING
559
560 /* flags for current->trace */
561 enum {
562 TSK_TRACE_FL_TRACE_BIT = 0,
563 TSK_TRACE_FL_GRAPH_BIT = 1,
564 };
565 enum {
566 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
567 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
568 };
569
set_tsk_trace_trace(struct task_struct * tsk)570 static inline void set_tsk_trace_trace(struct task_struct *tsk)
571 {
572 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
573 }
574
clear_tsk_trace_trace(struct task_struct * tsk)575 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
576 {
577 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
578 }
579
test_tsk_trace_trace(struct task_struct * tsk)580 static inline int test_tsk_trace_trace(struct task_struct *tsk)
581 {
582 return tsk->trace & TSK_TRACE_FL_TRACE;
583 }
584
set_tsk_trace_graph(struct task_struct * tsk)585 static inline void set_tsk_trace_graph(struct task_struct *tsk)
586 {
587 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
588 }
589
clear_tsk_trace_graph(struct task_struct * tsk)590 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
591 {
592 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
593 }
594
test_tsk_trace_graph(struct task_struct * tsk)595 static inline int test_tsk_trace_graph(struct task_struct *tsk)
596 {
597 return tsk->trace & TSK_TRACE_FL_GRAPH;
598 }
599
600 enum ftrace_dump_mode;
601
602 extern enum ftrace_dump_mode ftrace_dump_on_oops;
603
604 #ifdef CONFIG_PREEMPT
605 #define INIT_TRACE_RECURSION .trace_recursion = 0,
606 #endif
607
608 #endif /* CONFIG_TRACING */
609
610 #ifndef INIT_TRACE_RECURSION
611 #define INIT_TRACE_RECURSION
612 #endif
613
614 #ifdef CONFIG_FTRACE_SYSCALLS
615
616 unsigned long arch_syscall_addr(int nr);
617
618 #endif /* CONFIG_FTRACE_SYSCALLS */
619
620 #endif /* _LINUX_FTRACE_H */
621