d1ce0bec1b3fb625dc8bc9b50ba22bec891ec01f
[linux-2.6.git] / kernel / trace / trace.h
1 #ifndef _LINUX_KERNEL_TRACE_H
2 #define _LINUX_KERNEL_TRACE_H
3
4 #include <linux/fs.h>
5 #include <asm/atomic.h>
6 #include <linux/sched.h>
7 #include <linux/clocksource.h>
8 #include <linux/ring_buffer.h>
9 #include <linux/mmiotrace.h>
10 #include <linux/tracepoint.h>
11 #include <linux/ftrace.h>
12 #include <trace/boot.h>
13 #include <linux/kmemtrace.h>
14 #include <linux/hw_breakpoint.h>
15
16 #include <linux/trace_seq.h>
17 #include <linux/ftrace_event.h>
18
19 enum trace_type {
20         __TRACE_FIRST_TYPE = 0,
21
22         TRACE_FN,
23         TRACE_CTX,
24         TRACE_WAKE,
25         TRACE_STACK,
26         TRACE_PRINT,
27         TRACE_BPRINT,
28         TRACE_SPECIAL,
29         TRACE_MMIO_RW,
30         TRACE_MMIO_MAP,
31         TRACE_BRANCH,
32         TRACE_BOOT_CALL,
33         TRACE_BOOT_RET,
34         TRACE_GRAPH_RET,
35         TRACE_GRAPH_ENT,
36         TRACE_USER_STACK,
37         TRACE_KMEM_ALLOC,
38         TRACE_KMEM_FREE,
39         TRACE_BLK,
40         TRACE_KSYM,
41
42         __TRACE_LAST_TYPE,
43 };
44
45 enum kmemtrace_type_id {
46         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
47         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
48         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
49 };
50
51 extern struct tracer boot_tracer;
52
53 #undef __field
54 #define __field(type, item)             type    item;
55
56 #undef __field_struct
57 #define __field_struct(type, item)      __field(type, item)
58
59 #undef __field_desc
60 #define __field_desc(type, container, item)
61
62 #undef __array
63 #define __array(type, item, size)       type    item[size];
64
65 #undef __array_desc
66 #define __array_desc(type, container, item, size)
67
68 #undef __dynamic_array
69 #define __dynamic_array(type, item)     type    item[];
70
71 #undef F_STRUCT
72 #define F_STRUCT(args...)               args
73
74 #undef FTRACE_ENTRY
75 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
76         struct struct_name {                                    \
77                 struct trace_entry      ent;                    \
78                 tstruct                                         \
79         }
80
81 #undef TP_ARGS
82 #define TP_ARGS(args...)        args
83
84 #undef FTRACE_ENTRY_DUP
85 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
86
87 #include "trace_entries.h"
88
89 /*
90  * syscalls are special, and need special handling, this is why
91  * they are not included in trace_entries.h
92  */
93 struct syscall_trace_enter {
94         struct trace_entry      ent;
95         int                     nr;
96         unsigned long           args[];
97 };
98
99 struct syscall_trace_exit {
100         struct trace_entry      ent;
101         int                     nr;
102         long                    ret;
103 };
104
105 struct kprobe_trace_entry_head {
106         struct trace_entry      ent;
107         unsigned long           ip;
108 };
109
110 struct kretprobe_trace_entry_head {
111         struct trace_entry      ent;
112         unsigned long           func;
113         unsigned long           ret_ip;
114 };
115
116 /*
117  * trace_flag_type is an enumeration that holds different
118  * states when a trace occurs. These are:
119  *  IRQS_OFF            - interrupts were disabled
120  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
121  *  NEED_RESCHED        - reschedule is requested
122  *  HARDIRQ             - inside an interrupt handler
123  *  SOFTIRQ             - inside a softirq handler
124  */
125 enum trace_flag_type {
126         TRACE_FLAG_IRQS_OFF             = 0x01,
127         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
128         TRACE_FLAG_NEED_RESCHED         = 0x04,
129         TRACE_FLAG_HARDIRQ              = 0x08,
130         TRACE_FLAG_SOFTIRQ              = 0x10,
131 };
132
133 #define TRACE_BUF_SIZE          1024
134
135 /*
136  * The CPU trace array - it consists of thousands of trace entries
137  * plus some other descriptor data: (for example which task started
138  * the trace, etc.)
139  */
140 struct trace_array_cpu {
141         atomic_t                disabled;
142         void                    *buffer_page;   /* ring buffer spare */
143
144         unsigned long           saved_latency;
145         unsigned long           critical_start;
146         unsigned long           critical_end;
147         unsigned long           critical_sequence;
148         unsigned long           nice;
149         unsigned long           policy;
150         unsigned long           rt_priority;
151         unsigned long           skipped_entries;
152         cycle_t                 preempt_timestamp;
153         pid_t                   pid;
154         uid_t                   uid;
155         char                    comm[TASK_COMM_LEN];
156 };
157
158 /*
159  * The trace array - an array of per-CPU trace arrays. This is the
160  * highest level data structure that individual tracers deal with.
161  * They have on/off state as well:
162  */
163 struct trace_array {
164         struct ring_buffer      *buffer;
165         unsigned long           entries;
166         int                     cpu;
167         cycle_t                 time_start;
168         struct task_struct      *waiter;
169         struct trace_array_cpu  *data[NR_CPUS];
170 };
171
172 #define FTRACE_CMP_TYPE(var, type) \
173         __builtin_types_compatible_p(typeof(var), type *)
174
175 #undef IF_ASSIGN
176 #define IF_ASSIGN(var, entry, etype, id)                \
177         if (FTRACE_CMP_TYPE(var, etype)) {              \
178                 var = (typeof(var))(entry);             \
179                 WARN_ON(id && (entry)->type != id);     \
180                 break;                                  \
181         }
182
183 /* Will cause compile errors if type is not found. */
184 extern void __ftrace_bad_type(void);
185
186 /*
187  * The trace_assign_type is a verifier that the entry type is
188  * the same as the type being assigned. To add new types simply
189  * add a line with the following format:
190  *
191  * IF_ASSIGN(var, ent, type, id);
192  *
193  *  Where "type" is the trace type that includes the trace_entry
194  *  as the "ent" item. And "id" is the trace identifier that is
195  *  used in the trace_type enum.
196  *
197  *  If the type can have more than one id, then use zero.
198  */
199 #define trace_assign_type(var, ent)                                     \
200         do {                                                            \
201                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
202                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
203                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
204                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
205                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
206                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
207                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
208                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
209                           TRACE_MMIO_RW);                               \
210                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
211                           TRACE_MMIO_MAP);                              \
212                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
213                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
214                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
215                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
216                           TRACE_GRAPH_ENT);             \
217                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
218                           TRACE_GRAPH_RET);             \
219                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
220                           TRACE_KMEM_ALLOC);    \
221                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
222                           TRACE_KMEM_FREE);     \
223                 IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\
224                 __ftrace_bad_type();                                    \
225         } while (0)
226
227 /*
228  * An option specific to a tracer. This is a boolean value.
229  * The bit is the bit index that sets its value on the
230  * flags value in struct tracer_flags.
231  */
232 struct tracer_opt {
233         const char      *name; /* Will appear on the trace_options file */
234         u32             bit; /* Mask assigned in val field in tracer_flags */
235 };
236
237 /*
238  * The set of specific options for a tracer. Your tracer
239  * have to set the initial value of the flags val.
240  */
241 struct tracer_flags {
242         u32                     val;
243         struct tracer_opt       *opts;
244 };
245
246 /* Makes more easy to define a tracer opt */
247 #define TRACER_OPT(s, b)        .name = #s, .bit = b
248
249
250 /**
251  * struct tracer - a specific tracer and its callbacks to interact with debugfs
252  * @name: the name chosen to select it on the available_tracers file
253  * @init: called when one switches to this tracer (echo name > current_tracer)
254  * @reset: called when one switches to another tracer
255  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
256  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
257  * @open: called when the trace file is opened
258  * @pipe_open: called when the trace_pipe file is opened
259  * @wait_pipe: override how the user waits for traces on trace_pipe
260  * @close: called when the trace file is released
261  * @pipe_close: called when the trace_pipe file is released
262  * @read: override the default read callback on trace_pipe
263  * @splice_read: override the default splice_read callback on trace_pipe
264  * @selftest: selftest to run on boot (see trace_selftest.c)
265  * @print_headers: override the first lines that describe your columns
266  * @print_line: callback that prints a trace
267  * @set_flag: signals one of your private flags changed (trace_options file)
268  * @flags: your private flags
269  */
270 struct tracer {
271         const char              *name;
272         int                     (*init)(struct trace_array *tr);
273         void                    (*reset)(struct trace_array *tr);
274         void                    (*start)(struct trace_array *tr);
275         void                    (*stop)(struct trace_array *tr);
276         void                    (*open)(struct trace_iterator *iter);
277         void                    (*pipe_open)(struct trace_iterator *iter);
278         void                    (*wait_pipe)(struct trace_iterator *iter);
279         void                    (*close)(struct trace_iterator *iter);
280         void                    (*pipe_close)(struct trace_iterator *iter);
281         ssize_t                 (*read)(struct trace_iterator *iter,
282                                         struct file *filp, char __user *ubuf,
283                                         size_t cnt, loff_t *ppos);
284         ssize_t                 (*splice_read)(struct trace_iterator *iter,
285                                                struct file *filp,
286                                                loff_t *ppos,
287                                                struct pipe_inode_info *pipe,
288                                                size_t len,
289                                                unsigned int flags);
290 #ifdef CONFIG_FTRACE_STARTUP_TEST
291         int                     (*selftest)(struct tracer *trace,
292                                             struct trace_array *tr);
293 #endif
294         void                    (*print_header)(struct seq_file *m);
295         enum print_line_t       (*print_line)(struct trace_iterator *iter);
296         /* If you handled the flag setting, return 0 */
297         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
298         struct tracer           *next;
299         int                     print_max;
300         struct tracer_flags     *flags;
301 };
302
303
304 #define TRACE_PIPE_ALL_CPU      -1
305
306 int tracer_init(struct tracer *t, struct trace_array *tr);
307 int tracing_is_enabled(void);
308 void trace_wake_up(void);
309 void tracing_reset(struct trace_array *tr, int cpu);
310 void tracing_reset_online_cpus(struct trace_array *tr);
311 void tracing_reset_current(int cpu);
312 void tracing_reset_current_online_cpus(void);
313 int tracing_open_generic(struct inode *inode, struct file *filp);
314 struct dentry *trace_create_file(const char *name,
315                                  mode_t mode,
316                                  struct dentry *parent,
317                                  void *data,
318                                  const struct file_operations *fops);
319
320 struct dentry *tracing_init_dentry(void);
321 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
322
323 struct ring_buffer_event;
324
325 struct ring_buffer_event *
326 trace_buffer_lock_reserve(struct ring_buffer *buffer,
327                           int type,
328                           unsigned long len,
329                           unsigned long flags,
330                           int pc);
331 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
332                                 struct ring_buffer_event *event,
333                                 unsigned long flags, int pc);
334
335 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
336                                                 struct trace_array_cpu *data);
337
338 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
339                                           int *ent_cpu, u64 *ent_ts);
340
341 void default_wait_pipe(struct trace_iterator *iter);
342 void poll_wait_pipe(struct trace_iterator *iter);
343
344 void ftrace(struct trace_array *tr,
345                             struct trace_array_cpu *data,
346                             unsigned long ip,
347                             unsigned long parent_ip,
348                             unsigned long flags, int pc);
349 void tracing_sched_switch_trace(struct trace_array *tr,
350                                 struct task_struct *prev,
351                                 struct task_struct *next,
352                                 unsigned long flags, int pc);
353
354 void tracing_sched_wakeup_trace(struct trace_array *tr,
355                                 struct task_struct *wakee,
356                                 struct task_struct *cur,
357                                 unsigned long flags, int pc);
358 void trace_special(struct trace_array *tr,
359                    struct trace_array_cpu *data,
360                    unsigned long arg1,
361                    unsigned long arg2,
362                    unsigned long arg3, int pc);
363 void trace_function(struct trace_array *tr,
364                     unsigned long ip,
365                     unsigned long parent_ip,
366                     unsigned long flags, int pc);
367 void trace_default_header(struct seq_file *m);
368 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
369 int trace_empty(struct trace_iterator *iter);
370
371 void trace_graph_return(struct ftrace_graph_ret *trace);
372 int trace_graph_entry(struct ftrace_graph_ent *trace);
373 void set_graph_array(struct trace_array *tr);
374
375 void tracing_start_cmdline_record(void);
376 void tracing_stop_cmdline_record(void);
377 void tracing_sched_switch_assign_trace(struct trace_array *tr);
378 void tracing_stop_sched_switch_record(void);
379 void tracing_start_sched_switch_record(void);
380 int register_tracer(struct tracer *type);
381 void unregister_tracer(struct tracer *type);
382 int is_tracing_stopped(void);
383
384 extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
385
386 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
387
388 extern unsigned long tracing_thresh;
389
390 #ifdef CONFIG_TRACER_MAX_TRACE
391 extern unsigned long tracing_max_latency;
392
393 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
394 void update_max_tr_single(struct trace_array *tr,
395                           struct task_struct *tsk, int cpu);
396 #endif /* CONFIG_TRACER_MAX_TRACE */
397
398 #ifdef CONFIG_STACKTRACE
399 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
400                         int skip, int pc);
401
402 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
403                             int pc);
404
405 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
406                    int pc);
407 #else
408 static inline void ftrace_trace_stack(struct trace_array *tr,
409                                       unsigned long flags, int skip, int pc)
410 {
411 }
412
413 static inline void ftrace_trace_userstack(struct trace_array *tr,
414                                           unsigned long flags, int pc)
415 {
416 }
417
418 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
419                                  int skip, int pc)
420 {
421 }
422 #endif /* CONFIG_STACKTRACE */
423
424 extern cycle_t ftrace_now(int cpu);
425
426 extern void trace_find_cmdline(int pid, char comm[]);
427
428 #ifdef CONFIG_DYNAMIC_FTRACE
429 extern unsigned long ftrace_update_tot_cnt;
430 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
431 extern int DYN_FTRACE_TEST_NAME(void);
432 #endif
433
434 extern int ring_buffer_expanded;
435 extern bool tracing_selftest_disabled;
436 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
437
438 #ifdef CONFIG_FTRACE_STARTUP_TEST
439 extern int trace_selftest_startup_function(struct tracer *trace,
440                                            struct trace_array *tr);
441 extern int trace_selftest_startup_function_graph(struct tracer *trace,
442                                                  struct trace_array *tr);
443 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
444                                           struct trace_array *tr);
445 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
446                                              struct trace_array *tr);
447 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
448                                                  struct trace_array *tr);
449 extern int trace_selftest_startup_wakeup(struct tracer *trace,
450                                          struct trace_array *tr);
451 extern int trace_selftest_startup_nop(struct tracer *trace,
452                                          struct trace_array *tr);
453 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
454                                                struct trace_array *tr);
455 extern int trace_selftest_startup_sysprof(struct tracer *trace,
456                                                struct trace_array *tr);
457 extern int trace_selftest_startup_branch(struct tracer *trace,
458                                          struct trace_array *tr);
459 extern int trace_selftest_startup_ksym(struct tracer *trace,
460                                          struct trace_array *tr);
461 #endif /* CONFIG_FTRACE_STARTUP_TEST */
462
463 extern void *head_page(struct trace_array_cpu *data);
464 extern unsigned long long ns2usecs(cycle_t nsec);
465 extern int
466 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
467 extern int
468 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
469 extern int
470 trace_array_vprintk(struct trace_array *tr,
471                     unsigned long ip, const char *fmt, va_list args);
472 int trace_array_printk(struct trace_array *tr,
473                        unsigned long ip, const char *fmt, ...);
474
475 extern unsigned long trace_flags;
476
477 extern int trace_clock_id;
478
479 /* Standard output formatting function used for function return traces */
480 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
481
482 /* Flag options */
483 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
484 #define TRACE_GRAPH_PRINT_CPU           0x2
485 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
486 #define TRACE_GRAPH_PRINT_PROC          0x8
487 #define TRACE_GRAPH_PRINT_DURATION      0x10
488 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
489
490 extern enum print_line_t
491 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
492 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
493 extern enum print_line_t
494 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
495 extern void graph_trace_open(struct trace_iterator *iter);
496 extern void graph_trace_close(struct trace_iterator *iter);
497 extern int __trace_graph_entry(struct trace_array *tr,
498                                struct ftrace_graph_ent *trace,
499                                unsigned long flags, int pc);
500 extern void __trace_graph_return(struct trace_array *tr,
501                                  struct ftrace_graph_ret *trace,
502                                  unsigned long flags, int pc);
503
504
505 #ifdef CONFIG_DYNAMIC_FTRACE
506 /* TODO: make this variable */
507 #define FTRACE_GRAPH_MAX_FUNCS          32
508 extern int ftrace_graph_filter_enabled;
509 extern int ftrace_graph_count;
510 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
511
512 static inline int ftrace_graph_addr(unsigned long addr)
513 {
514         int i;
515
516         if (!ftrace_graph_filter_enabled)
517                 return 1;
518
519         for (i = 0; i < ftrace_graph_count; i++) {
520                 if (addr == ftrace_graph_funcs[i])
521                         return 1;
522         }
523
524         return 0;
525 }
526 #else
527 static inline int ftrace_graph_addr(unsigned long addr)
528 {
529         return 1;
530 }
531 #endif /* CONFIG_DYNAMIC_FTRACE */
532 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
533 static inline enum print_line_t
534 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
535 {
536         return TRACE_TYPE_UNHANDLED;
537 }
538 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
539
540 extern struct list_head ftrace_pids;
541
542 #ifdef CONFIG_FUNCTION_TRACER
543 static inline int ftrace_trace_task(struct task_struct *task)
544 {
545         if (list_empty(&ftrace_pids))
546                 return 1;
547
548         return test_tsk_trace_trace(task);
549 }
550 #else
551 static inline int ftrace_trace_task(struct task_struct *task)
552 {
553         return 1;
554 }
555 #endif
556
557 /*
558  * struct trace_parser - servers for reading the user input separated by spaces
559  * @cont: set if the input is not complete - no final space char was found
560  * @buffer: holds the parsed user input
561  * @idx: user input length
562  * @size: buffer size
563  */
564 struct trace_parser {
565         bool            cont;
566         char            *buffer;
567         unsigned        idx;
568         unsigned        size;
569 };
570
571 static inline bool trace_parser_loaded(struct trace_parser *parser)
572 {
573         return (parser->idx != 0);
574 }
575
576 static inline bool trace_parser_cont(struct trace_parser *parser)
577 {
578         return parser->cont;
579 }
580
581 static inline void trace_parser_clear(struct trace_parser *parser)
582 {
583         parser->cont = false;
584         parser->idx = 0;
585 }
586
587 extern int trace_parser_get_init(struct trace_parser *parser, int size);
588 extern void trace_parser_put(struct trace_parser *parser);
589 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
590         size_t cnt, loff_t *ppos);
591
592 /*
593  * trace_iterator_flags is an enumeration that defines bit
594  * positions into trace_flags that controls the output.
595  *
596  * NOTE: These bits must match the trace_options array in
597  *       trace.c.
598  */
599 enum trace_iterator_flags {
600         TRACE_ITER_PRINT_PARENT         = 0x01,
601         TRACE_ITER_SYM_OFFSET           = 0x02,
602         TRACE_ITER_SYM_ADDR             = 0x04,
603         TRACE_ITER_VERBOSE              = 0x08,
604         TRACE_ITER_RAW                  = 0x10,
605         TRACE_ITER_HEX                  = 0x20,
606         TRACE_ITER_BIN                  = 0x40,
607         TRACE_ITER_BLOCK                = 0x80,
608         TRACE_ITER_STACKTRACE           = 0x100,
609         TRACE_ITER_PRINTK               = 0x200,
610         TRACE_ITER_PREEMPTONLY          = 0x400,
611         TRACE_ITER_BRANCH               = 0x800,
612         TRACE_ITER_ANNOTATE             = 0x1000,
613         TRACE_ITER_USERSTACKTRACE       = 0x2000,
614         TRACE_ITER_SYM_USEROBJ          = 0x4000,
615         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
616         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
617         TRACE_ITER_LATENCY_FMT          = 0x20000,
618         TRACE_ITER_SLEEP_TIME           = 0x40000,
619         TRACE_ITER_GRAPH_TIME           = 0x80000,
620 };
621
622 /*
623  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
624  * control the output of kernel symbols.
625  */
626 #define TRACE_ITER_SYM_MASK \
627         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
628
629 extern struct tracer nop_trace;
630
631 /**
632  * ftrace_preempt_disable - disable preemption scheduler safe
633  *
634  * When tracing can happen inside the scheduler, there exists
635  * cases that the tracing might happen before the need_resched
636  * flag is checked. If this happens and the tracer calls
637  * preempt_enable (after a disable), a schedule might take place
638  * causing an infinite recursion.
639  *
640  * To prevent this, we read the need_resched flag before
641  * disabling preemption. When we want to enable preemption we
642  * check the flag, if it is set, then we call preempt_enable_no_resched.
643  * Otherwise, we call preempt_enable.
644  *
645  * The rational for doing the above is that if need_resched is set
646  * and we have yet to reschedule, we are either in an atomic location
647  * (where we do not need to check for scheduling) or we are inside
648  * the scheduler and do not want to resched.
649  */
650 static inline int ftrace_preempt_disable(void)
651 {
652         int resched;
653
654         resched = need_resched();
655         preempt_disable_notrace();
656
657         return resched;
658 }
659
660 /**
661  * ftrace_preempt_enable - enable preemption scheduler safe
662  * @resched: the return value from ftrace_preempt_disable
663  *
664  * This is a scheduler safe way to enable preemption and not miss
665  * any preemption checks. The disabled saved the state of preemption.
666  * If resched is set, then we are either inside an atomic or
667  * are inside the scheduler (we would have already scheduled
668  * otherwise). In this case, we do not want to call normal
669  * preempt_enable, but preempt_enable_no_resched instead.
670  */
671 static inline void ftrace_preempt_enable(int resched)
672 {
673         if (resched)
674                 preempt_enable_no_resched_notrace();
675         else
676                 preempt_enable_notrace();
677 }
678
679 #ifdef CONFIG_BRANCH_TRACER
680 extern int enable_branch_tracing(struct trace_array *tr);
681 extern void disable_branch_tracing(void);
682 static inline int trace_branch_enable(struct trace_array *tr)
683 {
684         if (trace_flags & TRACE_ITER_BRANCH)
685                 return enable_branch_tracing(tr);
686         return 0;
687 }
688 static inline void trace_branch_disable(void)
689 {
690         /* due to races, always disable */
691         disable_branch_tracing();
692 }
693 #else
694 static inline int trace_branch_enable(struct trace_array *tr)
695 {
696         return 0;
697 }
698 static inline void trace_branch_disable(void)
699 {
700 }
701 #endif /* CONFIG_BRANCH_TRACER */
702
703 /* set ring buffers to default size if not already done so */
704 int tracing_update_buffers(void);
705
706 /* trace event type bit fields, not numeric */
707 enum {
708         TRACE_EVENT_TYPE_PRINTF         = 1,
709         TRACE_EVENT_TYPE_RAW            = 2,
710 };
711
712 struct ftrace_event_field {
713         struct list_head        link;
714         char                    *name;
715         char                    *type;
716         int                     filter_type;
717         int                     offset;
718         int                     size;
719         int                     is_signed;
720 };
721
722 struct event_filter {
723         int                     n_preds;
724         struct filter_pred      **preds;
725         char                    *filter_string;
726 };
727
728 struct event_subsystem {
729         struct list_head        list;
730         const char              *name;
731         struct dentry           *entry;
732         struct event_filter     *filter;
733         int                     nr_events;
734 };
735
736 struct filter_pred;
737 struct regex;
738
739 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
740                                  int val1, int val2);
741
742 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
743
744 enum regex_type {
745         MATCH_FULL = 0,
746         MATCH_FRONT_ONLY,
747         MATCH_MIDDLE_ONLY,
748         MATCH_END_ONLY,
749 };
750
751 struct regex {
752         char                    pattern[MAX_FILTER_STR_VAL];
753         int                     len;
754         int                     field_len;
755         regex_match_func        match;
756 };
757
758 struct filter_pred {
759         filter_pred_fn_t        fn;
760         u64                     val;
761         struct regex            regex;
762         char                    *field_name;
763         int                     offset;
764         int                     not;
765         int                     op;
766         int                     pop_n;
767 };
768
769 extern enum regex_type
770 filter_parse_regex(char *buff, int len, char **search, int *not);
771 extern void print_event_filter(struct ftrace_event_call *call,
772                                struct trace_seq *s);
773 extern int apply_event_filter(struct ftrace_event_call *call,
774                               char *filter_string);
775 extern int apply_subsystem_event_filter(struct event_subsystem *system,
776                                         char *filter_string);
777 extern void print_subsystem_event_filter(struct event_subsystem *system,
778                                          struct trace_seq *s);
779 extern int filter_assign_type(const char *type);
780
781 static inline int
782 filter_check_discard(struct ftrace_event_call *call, void *rec,
783                      struct ring_buffer *buffer,
784                      struct ring_buffer_event *event)
785 {
786         if (unlikely(call->filter_active) &&
787             !filter_match_preds(call->filter, rec)) {
788                 ring_buffer_discard_commit(buffer, event);
789                 return 1;
790         }
791
792         return 0;
793 }
794
795 extern struct mutex event_mutex;
796 extern struct list_head ftrace_events;
797
798 extern const char *__start___trace_bprintk_fmt[];
799 extern const char *__stop___trace_bprintk_fmt[];
800
801 #undef FTRACE_ENTRY
802 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
803         extern struct ftrace_event_call                                 \
804         __attribute__((__aligned__(4))) event_##call;
805 #undef FTRACE_ENTRY_DUP
806 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
807         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
808 #include "trace_entries.h"
809
810 #endif /* _LINUX_KERNEL_TRACE_H */