ftrace.h 14 KB

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  1. #ifndef _LINUX_FTRACE_H
  2. #define _LINUX_FTRACE_H
  3. #include <linux/trace_clock.h>
  4. #include <linux/kallsyms.h>
  5. #include <linux/linkage.h>
  6. #include <linux/bitops.h>
  7. #include <linux/module.h>
  8. #include <linux/ktime.h>
  9. #include <linux/sched.h>
  10. #include <linux/types.h>
  11. #include <linux/init.h>
  12. #include <linux/fs.h>
  13. #include <asm/ftrace.h>
  14. #ifdef CONFIG_FUNCTION_TRACER
  15. extern int ftrace_enabled;
  16. extern int
  17. ftrace_enable_sysctl(struct ctl_table *table, int write,
  18. struct file *filp, void __user *buffer, size_t *lenp,
  19. loff_t *ppos);
  20. typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
  21. struct ftrace_ops {
  22. ftrace_func_t func;
  23. struct ftrace_ops *next;
  24. };
  25. extern int function_trace_stop;
  26. /*
  27. * Type of the current tracing.
  28. */
  29. enum ftrace_tracing_type_t {
  30. FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
  31. FTRACE_TYPE_RETURN, /* Hook the return of the function */
  32. };
  33. /* Current tracing type, default is FTRACE_TYPE_ENTER */
  34. extern enum ftrace_tracing_type_t ftrace_tracing_type;
  35. /**
  36. * ftrace_stop - stop function tracer.
  37. *
  38. * A quick way to stop the function tracer. Note this an on off switch,
  39. * it is not something that is recursive like preempt_disable.
  40. * This does not disable the calling of mcount, it only stops the
  41. * calling of functions from mcount.
  42. */
  43. static inline void ftrace_stop(void)
  44. {
  45. function_trace_stop = 1;
  46. }
  47. /**
  48. * ftrace_start - start the function tracer.
  49. *
  50. * This function is the inverse of ftrace_stop. This does not enable
  51. * the function tracing if the function tracer is disabled. This only
  52. * sets the function tracer flag to continue calling the functions
  53. * from mcount.
  54. */
  55. static inline void ftrace_start(void)
  56. {
  57. function_trace_stop = 0;
  58. }
  59. /*
  60. * The ftrace_ops must be a static and should also
  61. * be read_mostly. These functions do modify read_mostly variables
  62. * so use them sparely. Never free an ftrace_op or modify the
  63. * next pointer after it has been registered. Even after unregistering
  64. * it, the next pointer may still be used internally.
  65. */
  66. int register_ftrace_function(struct ftrace_ops *ops);
  67. int unregister_ftrace_function(struct ftrace_ops *ops);
  68. void clear_ftrace_function(void);
  69. extern void ftrace_stub(unsigned long a0, unsigned long a1);
  70. #else /* !CONFIG_FUNCTION_TRACER */
  71. # define register_ftrace_function(ops) do { } while (0)
  72. # define unregister_ftrace_function(ops) do { } while (0)
  73. # define clear_ftrace_function(ops) do { } while (0)
  74. static inline void ftrace_kill(void) { }
  75. static inline void ftrace_stop(void) { }
  76. static inline void ftrace_start(void) { }
  77. #endif /* CONFIG_FUNCTION_TRACER */
  78. #ifdef CONFIG_STACK_TRACER
  79. extern int stack_tracer_enabled;
  80. int
  81. stack_trace_sysctl(struct ctl_table *table, int write,
  82. struct file *file, void __user *buffer, size_t *lenp,
  83. loff_t *ppos);
  84. #endif
  85. struct ftrace_func_command {
  86. struct list_head list;
  87. char *name;
  88. int (*func)(char *func, char *cmd,
  89. char *params, int enable);
  90. };
  91. #ifdef CONFIG_DYNAMIC_FTRACE
  92. int ftrace_arch_code_modify_prepare(void);
  93. int ftrace_arch_code_modify_post_process(void);
  94. struct seq_file;
  95. struct ftrace_probe_ops {
  96. void (*func)(unsigned long ip,
  97. unsigned long parent_ip,
  98. void **data);
  99. int (*callback)(unsigned long ip, void **data);
  100. void (*free)(void **data);
  101. int (*print)(struct seq_file *m,
  102. unsigned long ip,
  103. struct ftrace_probe_ops *ops,
  104. void *data);
  105. };
  106. extern int
  107. register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
  108. void *data);
  109. extern void
  110. unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
  111. void *data);
  112. extern void
  113. unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
  114. extern void unregister_ftrace_function_probe_all(char *glob);
  115. enum {
  116. FTRACE_FL_FREE = (1 << 0),
  117. FTRACE_FL_FAILED = (1 << 1),
  118. FTRACE_FL_FILTER = (1 << 2),
  119. FTRACE_FL_ENABLED = (1 << 3),
  120. FTRACE_FL_NOTRACE = (1 << 4),
  121. FTRACE_FL_CONVERTED = (1 << 5),
  122. FTRACE_FL_FROZEN = (1 << 6),
  123. };
  124. struct dyn_ftrace {
  125. struct list_head list;
  126. unsigned long ip; /* address of mcount call-site */
  127. unsigned long flags;
  128. struct dyn_arch_ftrace arch;
  129. };
  130. int ftrace_force_update(void);
  131. void ftrace_set_filter(unsigned char *buf, int len, int reset);
  132. int register_ftrace_command(struct ftrace_func_command *cmd);
  133. int unregister_ftrace_command(struct ftrace_func_command *cmd);
  134. /* defined in arch */
  135. extern int ftrace_ip_converted(unsigned long ip);
  136. extern int ftrace_dyn_arch_init(void *data);
  137. extern int ftrace_update_ftrace_func(ftrace_func_t func);
  138. extern void ftrace_caller(void);
  139. extern void ftrace_call(void);
  140. extern void mcount_call(void);
  141. #ifndef FTRACE_ADDR
  142. #define FTRACE_ADDR ((unsigned long)ftrace_caller)
  143. #endif
  144. #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  145. extern void ftrace_graph_caller(void);
  146. extern int ftrace_enable_ftrace_graph_caller(void);
  147. extern int ftrace_disable_ftrace_graph_caller(void);
  148. #else
  149. static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
  150. static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
  151. #endif
  152. /**
  153. * ftrace_make_nop - convert code into nop
  154. * @mod: module structure if called by module load initialization
  155. * @rec: the mcount call site record
  156. * @addr: the address that the call site should be calling
  157. *
  158. * This is a very sensitive operation and great care needs
  159. * to be taken by the arch. The operation should carefully
  160. * read the location, check to see if what is read is indeed
  161. * what we expect it to be, and then on success of the compare,
  162. * it should write to the location.
  163. *
  164. * The code segment at @rec->ip should be a caller to @addr
  165. *
  166. * Return must be:
  167. * 0 on success
  168. * -EFAULT on error reading the location
  169. * -EINVAL on a failed compare of the contents
  170. * -EPERM on error writing to the location
  171. * Any other value will be considered a failure.
  172. */
  173. extern int ftrace_make_nop(struct module *mod,
  174. struct dyn_ftrace *rec, unsigned long addr);
  175. /**
  176. * ftrace_make_call - convert a nop call site into a call to addr
  177. * @rec: the mcount call site record
  178. * @addr: the address that the call site should call
  179. *
  180. * This is a very sensitive operation and great care needs
  181. * to be taken by the arch. The operation should carefully
  182. * read the location, check to see if what is read is indeed
  183. * what we expect it to be, and then on success of the compare,
  184. * it should write to the location.
  185. *
  186. * The code segment at @rec->ip should be a nop
  187. *
  188. * Return must be:
  189. * 0 on success
  190. * -EFAULT on error reading the location
  191. * -EINVAL on a failed compare of the contents
  192. * -EPERM on error writing to the location
  193. * Any other value will be considered a failure.
  194. */
  195. extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
  196. /* May be defined in arch */
  197. extern int ftrace_arch_read_dyn_info(char *buf, int size);
  198. extern int skip_trace(unsigned long ip);
  199. extern void ftrace_release(void *start, unsigned long size);
  200. extern void ftrace_disable_daemon(void);
  201. extern void ftrace_enable_daemon(void);
  202. #else
  203. # define skip_trace(ip) ({ 0; })
  204. # define ftrace_force_update() ({ 0; })
  205. # define ftrace_set_filter(buf, len, reset) do { } while (0)
  206. # define ftrace_disable_daemon() do { } while (0)
  207. # define ftrace_enable_daemon() do { } while (0)
  208. static inline void ftrace_release(void *start, unsigned long size) { }
  209. static inline int register_ftrace_command(struct ftrace_func_command *cmd)
  210. {
  211. return -EINVAL;
  212. }
  213. static inline int unregister_ftrace_command(char *cmd_name)
  214. {
  215. return -EINVAL;
  216. }
  217. #endif /* CONFIG_DYNAMIC_FTRACE */
  218. /* totally disable ftrace - can not re-enable after this */
  219. void ftrace_kill(void);
  220. static inline void tracer_disable(void)
  221. {
  222. #ifdef CONFIG_FUNCTION_TRACER
  223. ftrace_enabled = 0;
  224. #endif
  225. }
  226. /*
  227. * Ftrace disable/restore without lock. Some synchronization mechanism
  228. * must be used to prevent ftrace_enabled to be changed between
  229. * disable/restore.
  230. */
  231. static inline int __ftrace_enabled_save(void)
  232. {
  233. #ifdef CONFIG_FUNCTION_TRACER
  234. int saved_ftrace_enabled = ftrace_enabled;
  235. ftrace_enabled = 0;
  236. return saved_ftrace_enabled;
  237. #else
  238. return 0;
  239. #endif
  240. }
  241. static inline void __ftrace_enabled_restore(int enabled)
  242. {
  243. #ifdef CONFIG_FUNCTION_TRACER
  244. ftrace_enabled = enabled;
  245. #endif
  246. }
  247. #ifndef HAVE_ARCH_CALLER_ADDR
  248. # ifdef CONFIG_FRAME_POINTER
  249. # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
  250. # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
  251. # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
  252. # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
  253. # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
  254. # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
  255. # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
  256. # else
  257. # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
  258. # define CALLER_ADDR1 0UL
  259. # define CALLER_ADDR2 0UL
  260. # define CALLER_ADDR3 0UL
  261. # define CALLER_ADDR4 0UL
  262. # define CALLER_ADDR5 0UL
  263. # define CALLER_ADDR6 0UL
  264. # endif
  265. #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
  266. #ifdef CONFIG_IRQSOFF_TRACER
  267. extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
  268. extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
  269. #else
  270. # define time_hardirqs_on(a0, a1) do { } while (0)
  271. # define time_hardirqs_off(a0, a1) do { } while (0)
  272. #endif
  273. #ifdef CONFIG_PREEMPT_TRACER
  274. extern void trace_preempt_on(unsigned long a0, unsigned long a1);
  275. extern void trace_preempt_off(unsigned long a0, unsigned long a1);
  276. #else
  277. # define trace_preempt_on(a0, a1) do { } while (0)
  278. # define trace_preempt_off(a0, a1) do { } while (0)
  279. #endif
  280. #ifdef CONFIG_FTRACE_MCOUNT_RECORD
  281. extern void ftrace_init(void);
  282. extern void ftrace_init_module(struct module *mod,
  283. unsigned long *start, unsigned long *end);
  284. #else
  285. static inline void ftrace_init(void) { }
  286. static inline void
  287. ftrace_init_module(struct module *mod,
  288. unsigned long *start, unsigned long *end) { }
  289. #endif
  290. /*
  291. * Structure that defines an entry function trace.
  292. */
  293. struct ftrace_graph_ent {
  294. unsigned long func; /* Current function */
  295. int depth;
  296. };
  297. /*
  298. * Structure that defines a return function trace.
  299. */
  300. struct ftrace_graph_ret {
  301. unsigned long func; /* Current function */
  302. unsigned long long calltime;
  303. unsigned long long rettime;
  304. /* Number of functions that overran the depth limit for current task */
  305. unsigned long overrun;
  306. int depth;
  307. };
  308. #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  309. /*
  310. * Stack of return addresses for functions
  311. * of a thread.
  312. * Used in struct thread_info
  313. */
  314. struct ftrace_ret_stack {
  315. unsigned long ret;
  316. unsigned long func;
  317. unsigned long long calltime;
  318. };
  319. /*
  320. * Primary handler of a function return.
  321. * It relays on ftrace_return_to_handler.
  322. * Defined in entry_32/64.S
  323. */
  324. extern void return_to_handler(void);
  325. extern int
  326. ftrace_push_return_trace(unsigned long ret, unsigned long long time,
  327. unsigned long func, int *depth);
  328. extern void
  329. ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret);
  330. /*
  331. * Sometimes we don't want to trace a function with the function
  332. * graph tracer but we want them to keep traced by the usual function
  333. * tracer if the function graph tracer is not configured.
  334. */
  335. #define __notrace_funcgraph notrace
  336. /*
  337. * We want to which function is an entrypoint of a hardirq.
  338. * That will help us to put a signal on output.
  339. */
  340. #define __irq_entry __attribute__((__section__(".irqentry.text")))
  341. /* Limits of hardirq entrypoints */
  342. extern char __irqentry_text_start[];
  343. extern char __irqentry_text_end[];
  344. #define FTRACE_RETFUNC_DEPTH 50
  345. #define FTRACE_RETSTACK_ALLOC_SIZE 32
  346. /* Type of the callback handlers for tracing function graph*/
  347. typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
  348. typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
  349. extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
  350. trace_func_graph_ent_t entryfunc);
  351. extern void ftrace_graph_stop(void);
  352. /* The current handlers in use */
  353. extern trace_func_graph_ret_t ftrace_graph_return;
  354. extern trace_func_graph_ent_t ftrace_graph_entry;
  355. extern void unregister_ftrace_graph(void);
  356. extern void ftrace_graph_init_task(struct task_struct *t);
  357. extern void ftrace_graph_exit_task(struct task_struct *t);
  358. static inline int task_curr_ret_stack(struct task_struct *t)
  359. {
  360. return t->curr_ret_stack;
  361. }
  362. static inline void pause_graph_tracing(void)
  363. {
  364. atomic_inc(&current->tracing_graph_pause);
  365. }
  366. static inline void unpause_graph_tracing(void)
  367. {
  368. atomic_dec(&current->tracing_graph_pause);
  369. }
  370. #else
  371. #define __notrace_funcgraph
  372. #define __irq_entry
  373. static inline void ftrace_graph_init_task(struct task_struct *t) { }
  374. static inline void ftrace_graph_exit_task(struct task_struct *t) { }
  375. static inline int task_curr_ret_stack(struct task_struct *tsk)
  376. {
  377. return -1;
  378. }
  379. static inline void pause_graph_tracing(void) { }
  380. static inline void unpause_graph_tracing(void) { }
  381. #endif
  382. #ifdef CONFIG_TRACING
  383. #include <linux/sched.h>
  384. /* flags for current->trace */
  385. enum {
  386. TSK_TRACE_FL_TRACE_BIT = 0,
  387. TSK_TRACE_FL_GRAPH_BIT = 1,
  388. };
  389. enum {
  390. TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
  391. TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
  392. };
  393. static inline void set_tsk_trace_trace(struct task_struct *tsk)
  394. {
  395. set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
  396. }
  397. static inline void clear_tsk_trace_trace(struct task_struct *tsk)
  398. {
  399. clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
  400. }
  401. static inline int test_tsk_trace_trace(struct task_struct *tsk)
  402. {
  403. return tsk->trace & TSK_TRACE_FL_TRACE;
  404. }
  405. static inline void set_tsk_trace_graph(struct task_struct *tsk)
  406. {
  407. set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
  408. }
  409. static inline void clear_tsk_trace_graph(struct task_struct *tsk)
  410. {
  411. clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
  412. }
  413. static inline int test_tsk_trace_graph(struct task_struct *tsk)
  414. {
  415. return tsk->trace & TSK_TRACE_FL_GRAPH;
  416. }
  417. extern int ftrace_dump_on_oops;
  418. #endif /* CONFIG_TRACING */
  419. #ifdef CONFIG_HW_BRANCH_TRACER
  420. void trace_hw_branch(u64 from, u64 to);
  421. void trace_hw_branch_oops(void);
  422. #else /* CONFIG_HW_BRANCH_TRACER */
  423. static inline void trace_hw_branch(u64 from, u64 to) {}
  424. static inline void trace_hw_branch_oops(void) {}
  425. #endif /* CONFIG_HW_BRANCH_TRACER */
  426. #endif /* _LINUX_FTRACE_H */