trace.h 40 KB

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  1. #ifndef _LINUX_KERNEL_TRACE_H
  2. #define _LINUX_KERNEL_TRACE_H
  3. #include <linux/fs.h>
  4. #include <linux/atomic.h>
  5. #include <linux/sched.h>
  6. #include <linux/clocksource.h>
  7. #include <linux/ring_buffer.h>
  8. #include <linux/mmiotrace.h>
  9. #include <linux/tracepoint.h>
  10. #include <linux/ftrace.h>
  11. #include <linux/hw_breakpoint.h>
  12. #include <linux/trace_seq.h>
  13. #include <linux/trace_events.h>
  14. #include <linux/compiler.h>
  15. #include <linux/trace_seq.h>
  16. #ifdef CONFIG_FTRACE_SYSCALLS
  17. #include <asm/unistd.h> /* For NR_SYSCALLS */
  18. #include <asm/syscall.h> /* some archs define it here */
  19. #endif
  20. enum trace_type {
  21. __TRACE_FIRST_TYPE = 0,
  22. TRACE_FN,
  23. TRACE_CTX,
  24. TRACE_WAKE,
  25. TRACE_STACK,
  26. TRACE_PRINT,
  27. TRACE_BPRINT,
  28. TRACE_MMIO_RW,
  29. TRACE_MMIO_MAP,
  30. TRACE_BRANCH,
  31. TRACE_GRAPH_RET,
  32. TRACE_GRAPH_ENT,
  33. TRACE_USER_STACK,
  34. TRACE_BLK,
  35. TRACE_BPUTS,
  36. __TRACE_LAST_TYPE,
  37. };
  38. #undef __field
  39. #define __field(type, item) type item;
  40. #undef __field_struct
  41. #define __field_struct(type, item) __field(type, item)
  42. #undef __field_desc
  43. #define __field_desc(type, container, item)
  44. #undef __array
  45. #define __array(type, item, size) type item[size];
  46. #undef __array_desc
  47. #define __array_desc(type, container, item, size)
  48. #undef __dynamic_array
  49. #define __dynamic_array(type, item) type item[];
  50. #undef F_STRUCT
  51. #define F_STRUCT(args...) args
  52. #undef FTRACE_ENTRY
  53. #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
  54. struct struct_name { \
  55. struct trace_entry ent; \
  56. tstruct \
  57. }
  58. #undef TP_ARGS
  59. #define TP_ARGS(args...) args
  60. #undef FTRACE_ENTRY_DUP
  61. #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
  62. #undef FTRACE_ENTRY_REG
  63. #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
  64. filter, regfn) \
  65. FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
  66. filter)
  67. #include "trace_entries.h"
  68. /*
  69. * syscalls are special, and need special handling, this is why
  70. * they are not included in trace_entries.h
  71. */
  72. struct syscall_trace_enter {
  73. struct trace_entry ent;
  74. int nr;
  75. unsigned long args[];
  76. };
  77. struct syscall_trace_exit {
  78. struct trace_entry ent;
  79. int nr;
  80. long ret;
  81. };
  82. struct kprobe_trace_entry_head {
  83. struct trace_entry ent;
  84. unsigned long ip;
  85. };
  86. struct kretprobe_trace_entry_head {
  87. struct trace_entry ent;
  88. unsigned long func;
  89. unsigned long ret_ip;
  90. };
  91. /*
  92. * trace_flag_type is an enumeration that holds different
  93. * states when a trace occurs. These are:
  94. * IRQS_OFF - interrupts were disabled
  95. * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
  96. * NEED_RESCHED - reschedule is requested
  97. * HARDIRQ - inside an interrupt handler
  98. * SOFTIRQ - inside a softirq handler
  99. */
  100. enum trace_flag_type {
  101. TRACE_FLAG_IRQS_OFF = 0x01,
  102. TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
  103. TRACE_FLAG_NEED_RESCHED = 0x04,
  104. TRACE_FLAG_HARDIRQ = 0x08,
  105. TRACE_FLAG_SOFTIRQ = 0x10,
  106. TRACE_FLAG_PREEMPT_RESCHED = 0x20,
  107. };
  108. #define TRACE_BUF_SIZE 1024
  109. struct trace_array;
  110. /*
  111. * The CPU trace array - it consists of thousands of trace entries
  112. * plus some other descriptor data: (for example which task started
  113. * the trace, etc.)
  114. */
  115. struct trace_array_cpu {
  116. atomic_t disabled;
  117. void *buffer_page; /* ring buffer spare */
  118. unsigned long entries;
  119. unsigned long saved_latency;
  120. unsigned long critical_start;
  121. unsigned long critical_end;
  122. unsigned long critical_sequence;
  123. unsigned long nice;
  124. unsigned long policy;
  125. unsigned long rt_priority;
  126. unsigned long skipped_entries;
  127. cycle_t preempt_timestamp;
  128. pid_t pid;
  129. kuid_t uid;
  130. char comm[TASK_COMM_LEN];
  131. };
  132. struct tracer;
  133. struct trace_buffer {
  134. struct trace_array *tr;
  135. struct ring_buffer *buffer;
  136. struct trace_array_cpu __percpu *data;
  137. cycle_t time_start;
  138. int cpu;
  139. };
  140. /*
  141. * The trace array - an array of per-CPU trace arrays. This is the
  142. * highest level data structure that individual tracers deal with.
  143. * They have on/off state as well:
  144. */
  145. struct trace_array {
  146. struct list_head list;
  147. char *name;
  148. struct trace_buffer trace_buffer;
  149. #ifdef CONFIG_TRACER_MAX_TRACE
  150. /*
  151. * The max_buffer is used to snapshot the trace when a maximum
  152. * latency is reached, or when the user initiates a snapshot.
  153. * Some tracers will use this to store a maximum trace while
  154. * it continues examining live traces.
  155. *
  156. * The buffers for the max_buffer are set up the same as the trace_buffer
  157. * When a snapshot is taken, the buffer of the max_buffer is swapped
  158. * with the buffer of the trace_buffer and the buffers are reset for
  159. * the trace_buffer so the tracing can continue.
  160. */
  161. struct trace_buffer max_buffer;
  162. bool allocated_snapshot;
  163. unsigned long max_latency;
  164. #endif
  165. /*
  166. * max_lock is used to protect the swapping of buffers
  167. * when taking a max snapshot. The buffers themselves are
  168. * protected by per_cpu spinlocks. But the action of the swap
  169. * needs its own lock.
  170. *
  171. * This is defined as a arch_spinlock_t in order to help
  172. * with performance when lockdep debugging is enabled.
  173. *
  174. * It is also used in other places outside the update_max_tr
  175. * so it needs to be defined outside of the
  176. * CONFIG_TRACER_MAX_TRACE.
  177. */
  178. arch_spinlock_t max_lock;
  179. int buffer_disabled;
  180. #ifdef CONFIG_FTRACE_SYSCALLS
  181. int sys_refcount_enter;
  182. int sys_refcount_exit;
  183. struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
  184. struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
  185. #endif
  186. int stop_count;
  187. int clock_id;
  188. struct tracer *current_trace;
  189. unsigned int flags;
  190. raw_spinlock_t start_lock;
  191. struct dentry *dir;
  192. struct dentry *options;
  193. struct dentry *percpu_dir;
  194. struct dentry *event_dir;
  195. struct list_head systems;
  196. struct list_head events;
  197. cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
  198. int ref;
  199. #ifdef CONFIG_FUNCTION_TRACER
  200. struct ftrace_ops *ops;
  201. /* function tracing enabled */
  202. int function_enabled;
  203. #endif
  204. };
  205. enum {
  206. TRACE_ARRAY_FL_GLOBAL = (1 << 0)
  207. };
  208. extern struct list_head ftrace_trace_arrays;
  209. extern struct mutex trace_types_lock;
  210. extern int trace_array_get(struct trace_array *tr);
  211. extern void trace_array_put(struct trace_array *tr);
  212. /*
  213. * The global tracer (top) should be the first trace array added,
  214. * but we check the flag anyway.
  215. */
  216. static inline struct trace_array *top_trace_array(void)
  217. {
  218. struct trace_array *tr;
  219. if (list_empty(&ftrace_trace_arrays))
  220. return NULL;
  221. tr = list_entry(ftrace_trace_arrays.prev,
  222. typeof(*tr), list);
  223. WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
  224. return tr;
  225. }
  226. #define FTRACE_CMP_TYPE(var, type) \
  227. __builtin_types_compatible_p(typeof(var), type *)
  228. #undef IF_ASSIGN
  229. #define IF_ASSIGN(var, entry, etype, id) \
  230. if (FTRACE_CMP_TYPE(var, etype)) { \
  231. var = (typeof(var))(entry); \
  232. WARN_ON(id && (entry)->type != id); \
  233. break; \
  234. }
  235. /* Will cause compile errors if type is not found. */
  236. extern void __ftrace_bad_type(void);
  237. /*
  238. * The trace_assign_type is a verifier that the entry type is
  239. * the same as the type being assigned. To add new types simply
  240. * add a line with the following format:
  241. *
  242. * IF_ASSIGN(var, ent, type, id);
  243. *
  244. * Where "type" is the trace type that includes the trace_entry
  245. * as the "ent" item. And "id" is the trace identifier that is
  246. * used in the trace_type enum.
  247. *
  248. * If the type can have more than one id, then use zero.
  249. */
  250. #define trace_assign_type(var, ent) \
  251. do { \
  252. IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
  253. IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
  254. IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
  255. IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
  256. IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
  257. IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
  258. IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
  259. IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
  260. TRACE_MMIO_RW); \
  261. IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
  262. TRACE_MMIO_MAP); \
  263. IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
  264. IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
  265. TRACE_GRAPH_ENT); \
  266. IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
  267. TRACE_GRAPH_RET); \
  268. __ftrace_bad_type(); \
  269. } while (0)
  270. /*
  271. * An option specific to a tracer. This is a boolean value.
  272. * The bit is the bit index that sets its value on the
  273. * flags value in struct tracer_flags.
  274. */
  275. struct tracer_opt {
  276. const char *name; /* Will appear on the trace_options file */
  277. u32 bit; /* Mask assigned in val field in tracer_flags */
  278. };
  279. /*
  280. * The set of specific options for a tracer. Your tracer
  281. * have to set the initial value of the flags val.
  282. */
  283. struct tracer_flags {
  284. u32 val;
  285. struct tracer_opt *opts;
  286. };
  287. /* Makes more easy to define a tracer opt */
  288. #define TRACER_OPT(s, b) .name = #s, .bit = b
  289. /**
  290. * struct tracer - a specific tracer and its callbacks to interact with tracefs
  291. * @name: the name chosen to select it on the available_tracers file
  292. * @init: called when one switches to this tracer (echo name > current_tracer)
  293. * @reset: called when one switches to another tracer
  294. * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
  295. * @stop: called when tracing is paused (echo 0 > tracing_enabled)
  296. * @update_thresh: called when tracing_thresh is updated
  297. * @open: called when the trace file is opened
  298. * @pipe_open: called when the trace_pipe file is opened
  299. * @close: called when the trace file is released
  300. * @pipe_close: called when the trace_pipe file is released
  301. * @read: override the default read callback on trace_pipe
  302. * @splice_read: override the default splice_read callback on trace_pipe
  303. * @selftest: selftest to run on boot (see trace_selftest.c)
  304. * @print_headers: override the first lines that describe your columns
  305. * @print_line: callback that prints a trace
  306. * @set_flag: signals one of your private flags changed (trace_options file)
  307. * @flags: your private flags
  308. */
  309. struct tracer {
  310. const char *name;
  311. int (*init)(struct trace_array *tr);
  312. void (*reset)(struct trace_array *tr);
  313. void (*start)(struct trace_array *tr);
  314. void (*stop)(struct trace_array *tr);
  315. int (*update_thresh)(struct trace_array *tr);
  316. void (*open)(struct trace_iterator *iter);
  317. void (*pipe_open)(struct trace_iterator *iter);
  318. void (*close)(struct trace_iterator *iter);
  319. void (*pipe_close)(struct trace_iterator *iter);
  320. ssize_t (*read)(struct trace_iterator *iter,
  321. struct file *filp, char __user *ubuf,
  322. size_t cnt, loff_t *ppos);
  323. ssize_t (*splice_read)(struct trace_iterator *iter,
  324. struct file *filp,
  325. loff_t *ppos,
  326. struct pipe_inode_info *pipe,
  327. size_t len,
  328. unsigned int flags);
  329. #ifdef CONFIG_FTRACE_STARTUP_TEST
  330. int (*selftest)(struct tracer *trace,
  331. struct trace_array *tr);
  332. #endif
  333. void (*print_header)(struct seq_file *m);
  334. enum print_line_t (*print_line)(struct trace_iterator *iter);
  335. /* If you handled the flag setting, return 0 */
  336. int (*set_flag)(struct trace_array *tr,
  337. u32 old_flags, u32 bit, int set);
  338. /* Return 0 if OK with change, else return non-zero */
  339. int (*flag_changed)(struct trace_array *tr,
  340. u32 mask, int set);
  341. struct tracer *next;
  342. struct tracer_flags *flags;
  343. int enabled;
  344. int ref;
  345. bool print_max;
  346. bool allow_instances;
  347. #ifdef CONFIG_TRACER_MAX_TRACE
  348. bool use_max_tr;
  349. #endif
  350. };
  351. /* Only current can touch trace_recursion */
  352. /*
  353. * For function tracing recursion:
  354. * The order of these bits are important.
  355. *
  356. * When function tracing occurs, the following steps are made:
  357. * If arch does not support a ftrace feature:
  358. * call internal function (uses INTERNAL bits) which calls...
  359. * If callback is registered to the "global" list, the list
  360. * function is called and recursion checks the GLOBAL bits.
  361. * then this function calls...
  362. * The function callback, which can use the FTRACE bits to
  363. * check for recursion.
  364. *
  365. * Now if the arch does not suppport a feature, and it calls
  366. * the global list function which calls the ftrace callback
  367. * all three of these steps will do a recursion protection.
  368. * There's no reason to do one if the previous caller already
  369. * did. The recursion that we are protecting against will
  370. * go through the same steps again.
  371. *
  372. * To prevent the multiple recursion checks, if a recursion
  373. * bit is set that is higher than the MAX bit of the current
  374. * check, then we know that the check was made by the previous
  375. * caller, and we can skip the current check.
  376. */
  377. enum {
  378. TRACE_BUFFER_BIT,
  379. TRACE_BUFFER_NMI_BIT,
  380. TRACE_BUFFER_IRQ_BIT,
  381. TRACE_BUFFER_SIRQ_BIT,
  382. /* Start of function recursion bits */
  383. TRACE_FTRACE_BIT,
  384. TRACE_FTRACE_NMI_BIT,
  385. TRACE_FTRACE_IRQ_BIT,
  386. TRACE_FTRACE_SIRQ_BIT,
  387. /* INTERNAL_BITs must be greater than FTRACE_BITs */
  388. TRACE_INTERNAL_BIT,
  389. TRACE_INTERNAL_NMI_BIT,
  390. TRACE_INTERNAL_IRQ_BIT,
  391. TRACE_INTERNAL_SIRQ_BIT,
  392. TRACE_CONTROL_BIT,
  393. /*
  394. * Abuse of the trace_recursion.
  395. * As we need a way to maintain state if we are tracing the function
  396. * graph in irq because we want to trace a particular function that
  397. * was called in irq context but we have irq tracing off. Since this
  398. * can only be modified by current, we can reuse trace_recursion.
  399. */
  400. TRACE_IRQ_BIT,
  401. };
  402. #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
  403. #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
  404. #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
  405. #define TRACE_CONTEXT_BITS 4
  406. #define TRACE_FTRACE_START TRACE_FTRACE_BIT
  407. #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
  408. #define TRACE_LIST_START TRACE_INTERNAL_BIT
  409. #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
  410. #define TRACE_CONTEXT_MASK TRACE_LIST_MAX
  411. static __always_inline int trace_get_context_bit(void)
  412. {
  413. int bit;
  414. if (in_interrupt()) {
  415. if (in_nmi())
  416. bit = 0;
  417. else if (in_irq())
  418. bit = 1;
  419. else
  420. bit = 2;
  421. } else
  422. bit = 3;
  423. return bit;
  424. }
  425. static __always_inline int trace_test_and_set_recursion(int start, int max)
  426. {
  427. unsigned int val = current->trace_recursion;
  428. int bit;
  429. /* A previous recursion check was made */
  430. if ((val & TRACE_CONTEXT_MASK) > max)
  431. return 0;
  432. bit = trace_get_context_bit() + start;
  433. if (unlikely(val & (1 << bit)))
  434. return -1;
  435. val |= 1 << bit;
  436. current->trace_recursion = val;
  437. barrier();
  438. return bit;
  439. }
  440. static __always_inline void trace_clear_recursion(int bit)
  441. {
  442. unsigned int val = current->trace_recursion;
  443. if (!bit)
  444. return;
  445. bit = 1 << bit;
  446. val &= ~bit;
  447. barrier();
  448. current->trace_recursion = val;
  449. }
  450. static inline struct ring_buffer_iter *
  451. trace_buffer_iter(struct trace_iterator *iter, int cpu)
  452. {
  453. if (iter->buffer_iter && iter->buffer_iter[cpu])
  454. return iter->buffer_iter[cpu];
  455. return NULL;
  456. }
  457. int tracer_init(struct tracer *t, struct trace_array *tr);
  458. int tracing_is_enabled(void);
  459. void tracing_reset(struct trace_buffer *buf, int cpu);
  460. void tracing_reset_online_cpus(struct trace_buffer *buf);
  461. void tracing_reset_current(int cpu);
  462. void tracing_reset_all_online_cpus(void);
  463. int tracing_open_generic(struct inode *inode, struct file *filp);
  464. bool tracing_is_disabled(void);
  465. struct dentry *trace_create_file(const char *name,
  466. umode_t mode,
  467. struct dentry *parent,
  468. void *data,
  469. const struct file_operations *fops);
  470. struct dentry *tracing_init_dentry(void);
  471. struct ring_buffer_event;
  472. struct ring_buffer_event *
  473. trace_buffer_lock_reserve(struct ring_buffer *buffer,
  474. int type,
  475. unsigned long len,
  476. unsigned long flags,
  477. int pc);
  478. struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
  479. struct trace_array_cpu *data);
  480. struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
  481. int *ent_cpu, u64 *ent_ts);
  482. void __buffer_unlock_commit(struct ring_buffer *buffer,
  483. struct ring_buffer_event *event);
  484. int trace_empty(struct trace_iterator *iter);
  485. void *trace_find_next_entry_inc(struct trace_iterator *iter);
  486. void trace_init_global_iter(struct trace_iterator *iter);
  487. void tracing_iter_reset(struct trace_iterator *iter, int cpu);
  488. void trace_function(struct trace_array *tr,
  489. unsigned long ip,
  490. unsigned long parent_ip,
  491. unsigned long flags, int pc);
  492. void trace_graph_function(struct trace_array *tr,
  493. unsigned long ip,
  494. unsigned long parent_ip,
  495. unsigned long flags, int pc);
  496. void trace_latency_header(struct seq_file *m);
  497. void trace_default_header(struct seq_file *m);
  498. void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
  499. int trace_empty(struct trace_iterator *iter);
  500. void trace_graph_return(struct ftrace_graph_ret *trace);
  501. int trace_graph_entry(struct ftrace_graph_ent *trace);
  502. void set_graph_array(struct trace_array *tr);
  503. void tracing_start_cmdline_record(void);
  504. void tracing_stop_cmdline_record(void);
  505. int register_tracer(struct tracer *type);
  506. int is_tracing_stopped(void);
  507. loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
  508. extern cpumask_var_t __read_mostly tracing_buffer_mask;
  509. #define for_each_tracing_cpu(cpu) \
  510. for_each_cpu(cpu, tracing_buffer_mask)
  511. extern unsigned long nsecs_to_usecs(unsigned long nsecs);
  512. extern unsigned long tracing_thresh;
  513. #ifdef CONFIG_TRACER_MAX_TRACE
  514. void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
  515. void update_max_tr_single(struct trace_array *tr,
  516. struct task_struct *tsk, int cpu);
  517. #endif /* CONFIG_TRACER_MAX_TRACE */
  518. #ifdef CONFIG_STACKTRACE
  519. void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
  520. int skip, int pc);
  521. void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
  522. int skip, int pc, struct pt_regs *regs);
  523. void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
  524. int pc);
  525. void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
  526. int pc);
  527. #else
  528. static inline void ftrace_trace_stack(struct ring_buffer *buffer,
  529. unsigned long flags, int skip, int pc)
  530. {
  531. }
  532. static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
  533. unsigned long flags, int skip,
  534. int pc, struct pt_regs *regs)
  535. {
  536. }
  537. static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
  538. unsigned long flags, int pc)
  539. {
  540. }
  541. static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
  542. int skip, int pc)
  543. {
  544. }
  545. #endif /* CONFIG_STACKTRACE */
  546. extern cycle_t ftrace_now(int cpu);
  547. extern void trace_find_cmdline(int pid, char comm[]);
  548. #ifdef CONFIG_DYNAMIC_FTRACE
  549. extern unsigned long ftrace_update_tot_cnt;
  550. #endif
  551. #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
  552. extern int DYN_FTRACE_TEST_NAME(void);
  553. #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
  554. extern int DYN_FTRACE_TEST_NAME2(void);
  555. extern bool ring_buffer_expanded;
  556. extern bool tracing_selftest_disabled;
  557. DECLARE_PER_CPU(int, ftrace_cpu_disabled);
  558. #ifdef CONFIG_FTRACE_STARTUP_TEST
  559. extern int trace_selftest_startup_function(struct tracer *trace,
  560. struct trace_array *tr);
  561. extern int trace_selftest_startup_function_graph(struct tracer *trace,
  562. struct trace_array *tr);
  563. extern int trace_selftest_startup_irqsoff(struct tracer *trace,
  564. struct trace_array *tr);
  565. extern int trace_selftest_startup_preemptoff(struct tracer *trace,
  566. struct trace_array *tr);
  567. extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
  568. struct trace_array *tr);
  569. extern int trace_selftest_startup_wakeup(struct tracer *trace,
  570. struct trace_array *tr);
  571. extern int trace_selftest_startup_nop(struct tracer *trace,
  572. struct trace_array *tr);
  573. extern int trace_selftest_startup_sched_switch(struct tracer *trace,
  574. struct trace_array *tr);
  575. extern int trace_selftest_startup_branch(struct tracer *trace,
  576. struct trace_array *tr);
  577. /*
  578. * Tracer data references selftest functions that only occur
  579. * on boot up. These can be __init functions. Thus, when selftests
  580. * are enabled, then the tracers need to reference __init functions.
  581. */
  582. #define __tracer_data __refdata
  583. #else
  584. /* Tracers are seldom changed. Optimize when selftests are disabled. */
  585. #define __tracer_data __read_mostly
  586. #endif /* CONFIG_FTRACE_STARTUP_TEST */
  587. extern void *head_page(struct trace_array_cpu *data);
  588. extern unsigned long long ns2usecs(cycle_t nsec);
  589. extern int
  590. trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
  591. extern int
  592. trace_vprintk(unsigned long ip, const char *fmt, va_list args);
  593. extern int
  594. trace_array_vprintk(struct trace_array *tr,
  595. unsigned long ip, const char *fmt, va_list args);
  596. int trace_array_printk(struct trace_array *tr,
  597. unsigned long ip, const char *fmt, ...);
  598. int trace_array_printk_buf(struct ring_buffer *buffer,
  599. unsigned long ip, const char *fmt, ...);
  600. void trace_printk_seq(struct trace_seq *s);
  601. enum print_line_t print_trace_line(struct trace_iterator *iter);
  602. extern unsigned long trace_flags;
  603. extern char trace_find_mark(unsigned long long duration);
  604. /* Standard output formatting function used for function return traces */
  605. #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  606. /* Flag options */
  607. #define TRACE_GRAPH_PRINT_OVERRUN 0x1
  608. #define TRACE_GRAPH_PRINT_CPU 0x2
  609. #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
  610. #define TRACE_GRAPH_PRINT_PROC 0x8
  611. #define TRACE_GRAPH_PRINT_DURATION 0x10
  612. #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
  613. #define TRACE_GRAPH_PRINT_IRQS 0x40
  614. #define TRACE_GRAPH_PRINT_TAIL 0x80
  615. #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
  616. #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
  617. extern enum print_line_t
  618. print_graph_function_flags(struct trace_iterator *iter, u32 flags);
  619. extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
  620. extern void
  621. trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
  622. extern void graph_trace_open(struct trace_iterator *iter);
  623. extern void graph_trace_close(struct trace_iterator *iter);
  624. extern int __trace_graph_entry(struct trace_array *tr,
  625. struct ftrace_graph_ent *trace,
  626. unsigned long flags, int pc);
  627. extern void __trace_graph_return(struct trace_array *tr,
  628. struct ftrace_graph_ret *trace,
  629. unsigned long flags, int pc);
  630. #ifdef CONFIG_DYNAMIC_FTRACE
  631. /* TODO: make this variable */
  632. #define FTRACE_GRAPH_MAX_FUNCS 32
  633. extern int ftrace_graph_count;
  634. extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
  635. extern int ftrace_graph_notrace_count;
  636. extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS];
  637. static inline int ftrace_graph_addr(unsigned long addr)
  638. {
  639. int i;
  640. if (!ftrace_graph_count)
  641. return 1;
  642. for (i = 0; i < ftrace_graph_count; i++) {
  643. if (addr == ftrace_graph_funcs[i]) {
  644. /*
  645. * If no irqs are to be traced, but a set_graph_function
  646. * is set, and called by an interrupt handler, we still
  647. * want to trace it.
  648. */
  649. if (in_irq())
  650. trace_recursion_set(TRACE_IRQ_BIT);
  651. else
  652. trace_recursion_clear(TRACE_IRQ_BIT);
  653. return 1;
  654. }
  655. }
  656. return 0;
  657. }
  658. static inline int ftrace_graph_notrace_addr(unsigned long addr)
  659. {
  660. int i;
  661. if (!ftrace_graph_notrace_count)
  662. return 0;
  663. for (i = 0; i < ftrace_graph_notrace_count; i++) {
  664. if (addr == ftrace_graph_notrace_funcs[i])
  665. return 1;
  666. }
  667. return 0;
  668. }
  669. #else
  670. static inline int ftrace_graph_addr(unsigned long addr)
  671. {
  672. return 1;
  673. }
  674. static inline int ftrace_graph_notrace_addr(unsigned long addr)
  675. {
  676. return 0;
  677. }
  678. #endif /* CONFIG_DYNAMIC_FTRACE */
  679. #else /* CONFIG_FUNCTION_GRAPH_TRACER */
  680. static inline enum print_line_t
  681. print_graph_function_flags(struct trace_iterator *iter, u32 flags)
  682. {
  683. return TRACE_TYPE_UNHANDLED;
  684. }
  685. #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
  686. extern struct list_head ftrace_pids;
  687. #ifdef CONFIG_FUNCTION_TRACER
  688. extern bool ftrace_filter_param __initdata;
  689. static inline int ftrace_trace_task(struct task_struct *task)
  690. {
  691. if (list_empty(&ftrace_pids))
  692. return 1;
  693. return test_tsk_trace_trace(task);
  694. }
  695. extern int ftrace_is_dead(void);
  696. int ftrace_create_function_files(struct trace_array *tr,
  697. struct dentry *parent);
  698. void ftrace_destroy_function_files(struct trace_array *tr);
  699. void ftrace_init_global_array_ops(struct trace_array *tr);
  700. void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
  701. void ftrace_reset_array_ops(struct trace_array *tr);
  702. int using_ftrace_ops_list_func(void);
  703. #else
  704. static inline int ftrace_trace_task(struct task_struct *task)
  705. {
  706. return 1;
  707. }
  708. static inline int ftrace_is_dead(void) { return 0; }
  709. static inline int
  710. ftrace_create_function_files(struct trace_array *tr,
  711. struct dentry *parent)
  712. {
  713. return 0;
  714. }
  715. static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
  716. static inline __init void
  717. ftrace_init_global_array_ops(struct trace_array *tr) { }
  718. static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
  719. /* ftace_func_t type is not defined, use macro instead of static inline */
  720. #define ftrace_init_array_ops(tr, func) do { } while (0)
  721. #endif /* CONFIG_FUNCTION_TRACER */
  722. #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
  723. void ftrace_create_filter_files(struct ftrace_ops *ops,
  724. struct dentry *parent);
  725. void ftrace_destroy_filter_files(struct ftrace_ops *ops);
  726. #else
  727. /*
  728. * The ops parameter passed in is usually undefined.
  729. * This must be a macro.
  730. */
  731. #define ftrace_create_filter_files(ops, parent) do { } while (0)
  732. #define ftrace_destroy_filter_files(ops) do { } while (0)
  733. #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
  734. int ftrace_event_is_function(struct trace_event_call *call);
  735. /*
  736. * struct trace_parser - servers for reading the user input separated by spaces
  737. * @cont: set if the input is not complete - no final space char was found
  738. * @buffer: holds the parsed user input
  739. * @idx: user input length
  740. * @size: buffer size
  741. */
  742. struct trace_parser {
  743. bool cont;
  744. char *buffer;
  745. unsigned idx;
  746. unsigned size;
  747. };
  748. static inline bool trace_parser_loaded(struct trace_parser *parser)
  749. {
  750. return (parser->idx != 0);
  751. }
  752. static inline bool trace_parser_cont(struct trace_parser *parser)
  753. {
  754. return parser->cont;
  755. }
  756. static inline void trace_parser_clear(struct trace_parser *parser)
  757. {
  758. parser->cont = false;
  759. parser->idx = 0;
  760. }
  761. extern int trace_parser_get_init(struct trace_parser *parser, int size);
  762. extern void trace_parser_put(struct trace_parser *parser);
  763. extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
  764. size_t cnt, loff_t *ppos);
  765. /*
  766. * trace_iterator_flags is an enumeration that defines bit
  767. * positions into trace_flags that controls the output.
  768. *
  769. * NOTE: These bits must match the trace_options array in
  770. * trace.c.
  771. */
  772. enum trace_iterator_flags {
  773. TRACE_ITER_PRINT_PARENT = 0x01,
  774. TRACE_ITER_SYM_OFFSET = 0x02,
  775. TRACE_ITER_SYM_ADDR = 0x04,
  776. TRACE_ITER_VERBOSE = 0x08,
  777. TRACE_ITER_RAW = 0x10,
  778. TRACE_ITER_HEX = 0x20,
  779. TRACE_ITER_BIN = 0x40,
  780. TRACE_ITER_BLOCK = 0x80,
  781. TRACE_ITER_STACKTRACE = 0x100,
  782. TRACE_ITER_PRINTK = 0x200,
  783. TRACE_ITER_PREEMPTONLY = 0x400,
  784. TRACE_ITER_BRANCH = 0x800,
  785. TRACE_ITER_ANNOTATE = 0x1000,
  786. TRACE_ITER_USERSTACKTRACE = 0x2000,
  787. TRACE_ITER_SYM_USEROBJ = 0x4000,
  788. TRACE_ITER_PRINTK_MSGONLY = 0x8000,
  789. TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */
  790. TRACE_ITER_LATENCY_FMT = 0x20000,
  791. TRACE_ITER_SLEEP_TIME = 0x40000,
  792. TRACE_ITER_GRAPH_TIME = 0x80000,
  793. TRACE_ITER_RECORD_CMD = 0x100000,
  794. TRACE_ITER_OVERWRITE = 0x200000,
  795. TRACE_ITER_STOP_ON_FREE = 0x400000,
  796. TRACE_ITER_IRQ_INFO = 0x800000,
  797. TRACE_ITER_MARKERS = 0x1000000,
  798. TRACE_ITER_FUNCTION = 0x2000000,
  799. };
  800. /*
  801. * TRACE_ITER_SYM_MASK masks the options in trace_flags that
  802. * control the output of kernel symbols.
  803. */
  804. #define TRACE_ITER_SYM_MASK \
  805. (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
  806. extern struct tracer nop_trace;
  807. #ifdef CONFIG_BRANCH_TRACER
  808. extern int enable_branch_tracing(struct trace_array *tr);
  809. extern void disable_branch_tracing(void);
  810. static inline int trace_branch_enable(struct trace_array *tr)
  811. {
  812. if (trace_flags & TRACE_ITER_BRANCH)
  813. return enable_branch_tracing(tr);
  814. return 0;
  815. }
  816. static inline void trace_branch_disable(void)
  817. {
  818. /* due to races, always disable */
  819. disable_branch_tracing();
  820. }
  821. #else
  822. static inline int trace_branch_enable(struct trace_array *tr)
  823. {
  824. return 0;
  825. }
  826. static inline void trace_branch_disable(void)
  827. {
  828. }
  829. #endif /* CONFIG_BRANCH_TRACER */
  830. /* set ring buffers to default size if not already done so */
  831. int tracing_update_buffers(void);
  832. struct ftrace_event_field {
  833. struct list_head link;
  834. const char *name;
  835. const char *type;
  836. int filter_type;
  837. int offset;
  838. int size;
  839. int is_signed;
  840. };
  841. struct event_filter {
  842. int n_preds; /* Number assigned */
  843. int a_preds; /* allocated */
  844. struct filter_pred *preds;
  845. struct filter_pred *root;
  846. char *filter_string;
  847. };
  848. struct event_subsystem {
  849. struct list_head list;
  850. const char *name;
  851. struct event_filter *filter;
  852. int ref_count;
  853. };
  854. struct trace_subsystem_dir {
  855. struct list_head list;
  856. struct event_subsystem *subsystem;
  857. struct trace_array *tr;
  858. struct dentry *entry;
  859. int ref_count;
  860. int nr_events;
  861. };
  862. #define FILTER_PRED_INVALID ((unsigned short)-1)
  863. #define FILTER_PRED_IS_RIGHT (1 << 15)
  864. #define FILTER_PRED_FOLD (1 << 15)
  865. /*
  866. * The max preds is the size of unsigned short with
  867. * two flags at the MSBs. One bit is used for both the IS_RIGHT
  868. * and FOLD flags. The other is reserved.
  869. *
  870. * 2^14 preds is way more than enough.
  871. */
  872. #define MAX_FILTER_PRED 16384
  873. struct filter_pred;
  874. struct regex;
  875. typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
  876. typedef int (*regex_match_func)(char *str, struct regex *r, int len);
  877. enum regex_type {
  878. MATCH_FULL = 0,
  879. MATCH_FRONT_ONLY,
  880. MATCH_MIDDLE_ONLY,
  881. MATCH_END_ONLY,
  882. };
  883. struct regex {
  884. char pattern[MAX_FILTER_STR_VAL];
  885. int len;
  886. int field_len;
  887. regex_match_func match;
  888. };
  889. struct filter_pred {
  890. filter_pred_fn_t fn;
  891. u64 val;
  892. struct regex regex;
  893. unsigned short *ops;
  894. struct ftrace_event_field *field;
  895. int offset;
  896. int not;
  897. int op;
  898. unsigned short index;
  899. unsigned short parent;
  900. unsigned short left;
  901. unsigned short right;
  902. };
  903. extern enum regex_type
  904. filter_parse_regex(char *buff, int len, char **search, int *not);
  905. extern void print_event_filter(struct trace_event_file *file,
  906. struct trace_seq *s);
  907. extern int apply_event_filter(struct trace_event_file *file,
  908. char *filter_string);
  909. extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
  910. char *filter_string);
  911. extern void print_subsystem_event_filter(struct event_subsystem *system,
  912. struct trace_seq *s);
  913. extern int filter_assign_type(const char *type);
  914. extern int create_event_filter(struct trace_event_call *call,
  915. char *filter_str, bool set_str,
  916. struct event_filter **filterp);
  917. extern void free_event_filter(struct event_filter *filter);
  918. struct ftrace_event_field *
  919. trace_find_event_field(struct trace_event_call *call, char *name);
  920. extern void trace_event_enable_cmd_record(bool enable);
  921. extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
  922. extern int event_trace_del_tracer(struct trace_array *tr);
  923. extern struct trace_event_file *find_event_file(struct trace_array *tr,
  924. const char *system,
  925. const char *event);
  926. static inline void *event_file_data(struct file *filp)
  927. {
  928. return ACCESS_ONCE(file_inode(filp)->i_private);
  929. }
  930. extern struct mutex event_mutex;
  931. extern struct list_head ftrace_events;
  932. extern const struct file_operations event_trigger_fops;
  933. extern int register_trigger_cmds(void);
  934. extern void clear_event_triggers(struct trace_array *tr);
  935. struct event_trigger_data {
  936. unsigned long count;
  937. int ref;
  938. struct event_trigger_ops *ops;
  939. struct event_command *cmd_ops;
  940. struct event_filter __rcu *filter;
  941. char *filter_str;
  942. void *private_data;
  943. struct list_head list;
  944. };
  945. /**
  946. * struct event_trigger_ops - callbacks for trace event triggers
  947. *
  948. * The methods in this structure provide per-event trigger hooks for
  949. * various trigger operations.
  950. *
  951. * All the methods below, except for @init() and @free(), must be
  952. * implemented.
  953. *
  954. * @func: The trigger 'probe' function called when the triggering
  955. * event occurs. The data passed into this callback is the data
  956. * that was supplied to the event_command @reg() function that
  957. * registered the trigger (see struct event_command).
  958. *
  959. * @init: An optional initialization function called for the trigger
  960. * when the trigger is registered (via the event_command reg()
  961. * function). This can be used to perform per-trigger
  962. * initialization such as incrementing a per-trigger reference
  963. * count, for instance. This is usually implemented by the
  964. * generic utility function @event_trigger_init() (see
  965. * trace_event_triggers.c).
  966. *
  967. * @free: An optional de-initialization function called for the
  968. * trigger when the trigger is unregistered (via the
  969. * event_command @reg() function). This can be used to perform
  970. * per-trigger de-initialization such as decrementing a
  971. * per-trigger reference count and freeing corresponding trigger
  972. * data, for instance. This is usually implemented by the
  973. * generic utility function @event_trigger_free() (see
  974. * trace_event_triggers.c).
  975. *
  976. * @print: The callback function invoked to have the trigger print
  977. * itself. This is usually implemented by a wrapper function
  978. * that calls the generic utility function @event_trigger_print()
  979. * (see trace_event_triggers.c).
  980. */
  981. struct event_trigger_ops {
  982. void (*func)(struct event_trigger_data *data);
  983. int (*init)(struct event_trigger_ops *ops,
  984. struct event_trigger_data *data);
  985. void (*free)(struct event_trigger_ops *ops,
  986. struct event_trigger_data *data);
  987. int (*print)(struct seq_file *m,
  988. struct event_trigger_ops *ops,
  989. struct event_trigger_data *data);
  990. };
  991. /**
  992. * struct event_command - callbacks and data members for event commands
  993. *
  994. * Event commands are invoked by users by writing the command name
  995. * into the 'trigger' file associated with a trace event. The
  996. * parameters associated with a specific invocation of an event
  997. * command are used to create an event trigger instance, which is
  998. * added to the list of trigger instances associated with that trace
  999. * event. When the event is hit, the set of triggers associated with
  1000. * that event is invoked.
  1001. *
  1002. * The data members in this structure provide per-event command data
  1003. * for various event commands.
  1004. *
  1005. * All the data members below, except for @post_trigger, must be set
  1006. * for each event command.
  1007. *
  1008. * @name: The unique name that identifies the event command. This is
  1009. * the name used when setting triggers via trigger files.
  1010. *
  1011. * @trigger_type: A unique id that identifies the event command
  1012. * 'type'. This value has two purposes, the first to ensure that
  1013. * only one trigger of the same type can be set at a given time
  1014. * for a particular event e.g. it doesn't make sense to have both
  1015. * a traceon and traceoff trigger attached to a single event at
  1016. * the same time, so traceon and traceoff have the same type
  1017. * though they have different names. The @trigger_type value is
  1018. * also used as a bit value for deferring the actual trigger
  1019. * action until after the current event is finished. Some
  1020. * commands need to do this if they themselves log to the trace
  1021. * buffer (see the @post_trigger() member below). @trigger_type
  1022. * values are defined by adding new values to the trigger_type
  1023. * enum in include/linux/trace_events.h.
  1024. *
  1025. * @post_trigger: A flag that says whether or not this command needs
  1026. * to have its action delayed until after the current event has
  1027. * been closed. Some triggers need to avoid being invoked while
  1028. * an event is currently in the process of being logged, since
  1029. * the trigger may itself log data into the trace buffer. Thus
  1030. * we make sure the current event is committed before invoking
  1031. * those triggers. To do that, the trigger invocation is split
  1032. * in two - the first part checks the filter using the current
  1033. * trace record; if a command has the @post_trigger flag set, it
  1034. * sets a bit for itself in the return value, otherwise it
  1035. * directly invokes the trigger. Once all commands have been
  1036. * either invoked or set their return flag, the current record is
  1037. * either committed or discarded. At that point, if any commands
  1038. * have deferred their triggers, those commands are finally
  1039. * invoked following the close of the current event. In other
  1040. * words, if the event_trigger_ops @func() probe implementation
  1041. * itself logs to the trace buffer, this flag should be set,
  1042. * otherwise it can be left unspecified.
  1043. *
  1044. * All the methods below, except for @set_filter(), must be
  1045. * implemented.
  1046. *
  1047. * @func: The callback function responsible for parsing and
  1048. * registering the trigger written to the 'trigger' file by the
  1049. * user. It allocates the trigger instance and registers it with
  1050. * the appropriate trace event. It makes use of the other
  1051. * event_command callback functions to orchestrate this, and is
  1052. * usually implemented by the generic utility function
  1053. * @event_trigger_callback() (see trace_event_triggers.c).
  1054. *
  1055. * @reg: Adds the trigger to the list of triggers associated with the
  1056. * event, and enables the event trigger itself, after
  1057. * initializing it (via the event_trigger_ops @init() function).
  1058. * This is also where commands can use the @trigger_type value to
  1059. * make the decision as to whether or not multiple instances of
  1060. * the trigger should be allowed. This is usually implemented by
  1061. * the generic utility function @register_trigger() (see
  1062. * trace_event_triggers.c).
  1063. *
  1064. * @unreg: Removes the trigger from the list of triggers associated
  1065. * with the event, and disables the event trigger itself, after
  1066. * initializing it (via the event_trigger_ops @free() function).
  1067. * This is usually implemented by the generic utility function
  1068. * @unregister_trigger() (see trace_event_triggers.c).
  1069. *
  1070. * @set_filter: An optional function called to parse and set a filter
  1071. * for the trigger. If no @set_filter() method is set for the
  1072. * event command, filters set by the user for the command will be
  1073. * ignored. This is usually implemented by the generic utility
  1074. * function @set_trigger_filter() (see trace_event_triggers.c).
  1075. *
  1076. * @get_trigger_ops: The callback function invoked to retrieve the
  1077. * event_trigger_ops implementation associated with the command.
  1078. */
  1079. struct event_command {
  1080. struct list_head list;
  1081. char *name;
  1082. enum event_trigger_type trigger_type;
  1083. bool post_trigger;
  1084. int (*func)(struct event_command *cmd_ops,
  1085. struct trace_event_file *file,
  1086. char *glob, char *cmd, char *params);
  1087. int (*reg)(char *glob,
  1088. struct event_trigger_ops *ops,
  1089. struct event_trigger_data *data,
  1090. struct trace_event_file *file);
  1091. void (*unreg)(char *glob,
  1092. struct event_trigger_ops *ops,
  1093. struct event_trigger_data *data,
  1094. struct trace_event_file *file);
  1095. int (*set_filter)(char *filter_str,
  1096. struct event_trigger_data *data,
  1097. struct trace_event_file *file);
  1098. struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
  1099. };
  1100. extern int trace_event_enable_disable(struct trace_event_file *file,
  1101. int enable, int soft_disable);
  1102. extern int tracing_alloc_snapshot(void);
  1103. extern const char *__start___trace_bprintk_fmt[];
  1104. extern const char *__stop___trace_bprintk_fmt[];
  1105. extern const char *__start___tracepoint_str[];
  1106. extern const char *__stop___tracepoint_str[];
  1107. void trace_printk_init_buffers(void);
  1108. void trace_printk_start_comm(void);
  1109. int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
  1110. int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
  1111. /*
  1112. * Normal trace_printk() and friends allocates special buffers
  1113. * to do the manipulation, as well as saves the print formats
  1114. * into sections to display. But the trace infrastructure wants
  1115. * to use these without the added overhead at the price of being
  1116. * a bit slower (used mainly for warnings, where we don't care
  1117. * about performance). The internal_trace_puts() is for such
  1118. * a purpose.
  1119. */
  1120. #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
  1121. #undef FTRACE_ENTRY
  1122. #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
  1123. extern struct trace_event_call \
  1124. __aligned(4) event_##call;
  1125. #undef FTRACE_ENTRY_DUP
  1126. #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
  1127. FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
  1128. filter)
  1129. #include "trace_entries.h"
  1130. #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
  1131. int perf_ftrace_event_register(struct trace_event_call *call,
  1132. enum trace_reg type, void *data);
  1133. #else
  1134. #define perf_ftrace_event_register NULL
  1135. #endif
  1136. #ifdef CONFIG_FTRACE_SYSCALLS
  1137. void init_ftrace_syscalls(void);
  1138. #else
  1139. static inline void init_ftrace_syscalls(void) { }
  1140. #endif
  1141. #ifdef CONFIG_EVENT_TRACING
  1142. void trace_event_init(void);
  1143. void trace_event_enum_update(struct trace_enum_map **map, int len);
  1144. #else
  1145. static inline void __init trace_event_init(void) { }
  1146. static inline void trace_event_enum_update(struct trace_enum_map **map, int len) { }
  1147. #endif
  1148. extern struct trace_iterator *tracepoint_print_iter;
  1149. #endif /* _LINUX_KERNEL_TRACE_H */