d308195d40aadd6d4fdf2cae1091c9c8d30ebcbf
[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/ftrace.h>
11 #include <trace/boot.h>
12 #include <linux/kmemtrace.h>
13 #include <trace/power.h>
14
15 #include <linux/trace_seq.h>
16 #include <linux/ftrace_event.h>
17
18 enum trace_type {
19         __TRACE_FIRST_TYPE = 0,
20
21         TRACE_FN,
22         TRACE_CTX,
23         TRACE_WAKE,
24         TRACE_STACK,
25         TRACE_PRINT,
26         TRACE_BPRINT,
27         TRACE_SPECIAL,
28         TRACE_MMIO_RW,
29         TRACE_MMIO_MAP,
30         TRACE_BRANCH,
31         TRACE_BOOT_CALL,
32         TRACE_BOOT_RET,
33         TRACE_GRAPH_RET,
34         TRACE_GRAPH_ENT,
35         TRACE_USER_STACK,
36         TRACE_HW_BRANCHES,
37         TRACE_KMEM_ALLOC,
38         TRACE_KMEM_FREE,
39         TRACE_POWER,
40         TRACE_BLK,
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 __array
57 #define __array(type, item, size)       type    item[size];
58
59 #undef __dynamic_array
60 #define __dynamic_array(type, item)     type    item[];
61
62 #undef F_STRUCT
63 #define F_STRUCT(args...)               args
64
65 #undef FTRACE_ENTRY
66 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
67         struct struct_name {                                    \
68                 struct trace_entry      ent;                    \
69                 tstruct                                         \
70         }
71
72 #undef TP_ARGS
73 #define TP_ARGS(args...)        args
74
75 #undef FTRACE_ENTRY_DUP
76 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
77
78 #include "trace_entries.h"
79
80 /*
81  * syscalls are special, and need special handling, this is why
82  * they are not included in trace_entries.h
83  */
84 struct syscall_trace_enter {
85         struct trace_entry      ent;
86         int                     nr;
87         unsigned long           args[];
88 };
89
90 struct syscall_trace_exit {
91         struct trace_entry      ent;
92         int                     nr;
93         unsigned long           ret;
94 };
95
96 /*
97  * trace_flag_type is an enumeration that holds different
98  * states when a trace occurs. These are:
99  *  IRQS_OFF            - interrupts were disabled
100  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
101  *  NEED_RESCHED        - reschedule is requested
102  *  HARDIRQ             - inside an interrupt handler
103  *  SOFTIRQ             - inside a softirq handler
104  */
105 enum trace_flag_type {
106         TRACE_FLAG_IRQS_OFF             = 0x01,
107         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
108         TRACE_FLAG_NEED_RESCHED         = 0x04,
109         TRACE_FLAG_HARDIRQ              = 0x08,
110         TRACE_FLAG_SOFTIRQ              = 0x10,
111 };
112
113 #define TRACE_BUF_SIZE          1024
114
115 /*
116  * The CPU trace array - it consists of thousands of trace entries
117  * plus some other descriptor data: (for example which task started
118  * the trace, etc.)
119  */
120 struct trace_array_cpu {
121         atomic_t                disabled;
122         void                    *buffer_page;   /* ring buffer spare */
123
124         unsigned long           saved_latency;
125         unsigned long           critical_start;
126         unsigned long           critical_end;
127         unsigned long           critical_sequence;
128         unsigned long           nice;
129         unsigned long           policy;
130         unsigned long           rt_priority;
131         unsigned long           skipped_entries;
132         cycle_t                 preempt_timestamp;
133         pid_t                   pid;
134         uid_t                   uid;
135         char                    comm[TASK_COMM_LEN];
136 };
137
138 /*
139  * The trace array - an array of per-CPU trace arrays. This is the
140  * highest level data structure that individual tracers deal with.
141  * They have on/off state as well:
142  */
143 struct trace_array {
144         struct ring_buffer      *buffer;
145         unsigned long           entries;
146         int                     cpu;
147         cycle_t                 time_start;
148         struct task_struct      *waiter;
149         struct trace_array_cpu  *data[NR_CPUS];
150 };
151
152 #define FTRACE_CMP_TYPE(var, type) \
153         __builtin_types_compatible_p(typeof(var), type *)
154
155 #undef IF_ASSIGN
156 #define IF_ASSIGN(var, entry, etype, id)                \
157         if (FTRACE_CMP_TYPE(var, etype)) {              \
158                 var = (typeof(var))(entry);             \
159                 WARN_ON(id && (entry)->type != id);     \
160                 break;                                  \
161         }
162
163 /* Will cause compile errors if type is not found. */
164 extern void __ftrace_bad_type(void);
165
166 /*
167  * The trace_assign_type is a verifier that the entry type is
168  * the same as the type being assigned. To add new types simply
169  * add a line with the following format:
170  *
171  * IF_ASSIGN(var, ent, type, id);
172  *
173  *  Where "type" is the trace type that includes the trace_entry
174  *  as the "ent" item. And "id" is the trace identifier that is
175  *  used in the trace_type enum.
176  *
177  *  If the type can have more than one id, then use zero.
178  */
179 #define trace_assign_type(var, ent)                                     \
180         do {                                                            \
181                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
182                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
183                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
184                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
185                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
186                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
187                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
188                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
189                           TRACE_MMIO_RW);                               \
190                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
191                           TRACE_MMIO_MAP);                              \
192                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
193                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
194                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
195                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
196                           TRACE_GRAPH_ENT);             \
197                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
198                           TRACE_GRAPH_RET);             \
199                 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
200                 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
201                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
202                           TRACE_KMEM_ALLOC);    \
203                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
204                           TRACE_KMEM_FREE);     \
205                 __ftrace_bad_type();                                    \
206         } while (0)
207
208 /*
209  * An option specific to a tracer. This is a boolean value.
210  * The bit is the bit index that sets its value on the
211  * flags value in struct tracer_flags.
212  */
213 struct tracer_opt {
214         const char      *name; /* Will appear on the trace_options file */
215         u32             bit; /* Mask assigned in val field in tracer_flags */
216 };
217
218 /*
219  * The set of specific options for a tracer. Your tracer
220  * have to set the initial value of the flags val.
221  */
222 struct tracer_flags {
223         u32                     val;
224         struct tracer_opt       *opts;
225 };
226
227 /* Makes more easy to define a tracer opt */
228 #define TRACER_OPT(s, b)        .name = #s, .bit = b
229
230
231 /**
232  * struct tracer - a specific tracer and its callbacks to interact with debugfs
233  * @name: the name chosen to select it on the available_tracers file
234  * @init: called when one switches to this tracer (echo name > current_tracer)
235  * @reset: called when one switches to another tracer
236  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
237  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
238  * @open: called when the trace file is opened
239  * @pipe_open: called when the trace_pipe file is opened
240  * @wait_pipe: override how the user waits for traces on trace_pipe
241  * @close: called when the trace file is released
242  * @read: override the default read callback on trace_pipe
243  * @splice_read: override the default splice_read callback on trace_pipe
244  * @selftest: selftest to run on boot (see trace_selftest.c)
245  * @print_headers: override the first lines that describe your columns
246  * @print_line: callback that prints a trace
247  * @set_flag: signals one of your private flags changed (trace_options file)
248  * @flags: your private flags
249  */
250 struct tracer {
251         const char              *name;
252         int                     (*init)(struct trace_array *tr);
253         void                    (*reset)(struct trace_array *tr);
254         void                    (*start)(struct trace_array *tr);
255         void                    (*stop)(struct trace_array *tr);
256         void                    (*open)(struct trace_iterator *iter);
257         void                    (*pipe_open)(struct trace_iterator *iter);
258         void                    (*wait_pipe)(struct trace_iterator *iter);
259         void                    (*close)(struct trace_iterator *iter);
260         ssize_t                 (*read)(struct trace_iterator *iter,
261                                         struct file *filp, char __user *ubuf,
262                                         size_t cnt, loff_t *ppos);
263         ssize_t                 (*splice_read)(struct trace_iterator *iter,
264                                                struct file *filp,
265                                                loff_t *ppos,
266                                                struct pipe_inode_info *pipe,
267                                                size_t len,
268                                                unsigned int flags);
269 #ifdef CONFIG_FTRACE_STARTUP_TEST
270         int                     (*selftest)(struct tracer *trace,
271                                             struct trace_array *tr);
272 #endif
273         void                    (*print_header)(struct seq_file *m);
274         enum print_line_t       (*print_line)(struct trace_iterator *iter);
275         /* If you handled the flag setting, return 0 */
276         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
277         struct tracer           *next;
278         int                     print_max;
279         struct tracer_flags     *flags;
280 };
281
282
283 #define TRACE_PIPE_ALL_CPU      -1
284
285 int tracer_init(struct tracer *t, struct trace_array *tr);
286 int tracing_is_enabled(void);
287 void trace_wake_up(void);
288 void tracing_reset(struct trace_array *tr, int cpu);
289 void tracing_reset_online_cpus(struct trace_array *tr);
290 void tracing_reset_current(int cpu);
291 void tracing_reset_current_online_cpus(void);
292 int tracing_open_generic(struct inode *inode, struct file *filp);
293 struct dentry *trace_create_file(const char *name,
294                                  mode_t mode,
295                                  struct dentry *parent,
296                                  void *data,
297                                  const struct file_operations *fops);
298
299 struct dentry *tracing_init_dentry(void);
300 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
301
302 struct ring_buffer_event;
303
304 struct ring_buffer_event *
305 trace_buffer_lock_reserve(struct ring_buffer *buffer,
306                           int type,
307                           unsigned long len,
308                           unsigned long flags,
309                           int pc);
310 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
311                                 struct ring_buffer_event *event,
312                                 unsigned long flags, int pc);
313
314 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
315                                                 struct trace_array_cpu *data);
316
317 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
318                                           int *ent_cpu, u64 *ent_ts);
319
320 void default_wait_pipe(struct trace_iterator *iter);
321 void poll_wait_pipe(struct trace_iterator *iter);
322
323 void ftrace(struct trace_array *tr,
324                             struct trace_array_cpu *data,
325                             unsigned long ip,
326                             unsigned long parent_ip,
327                             unsigned long flags, int pc);
328 void tracing_sched_switch_trace(struct trace_array *tr,
329                                 struct task_struct *prev,
330                                 struct task_struct *next,
331                                 unsigned long flags, int pc);
332
333 void tracing_sched_wakeup_trace(struct trace_array *tr,
334                                 struct task_struct *wakee,
335                                 struct task_struct *cur,
336                                 unsigned long flags, int pc);
337 void trace_special(struct trace_array *tr,
338                    struct trace_array_cpu *data,
339                    unsigned long arg1,
340                    unsigned long arg2,
341                    unsigned long arg3, int pc);
342 void trace_function(struct trace_array *tr,
343                     unsigned long ip,
344                     unsigned long parent_ip,
345                     unsigned long flags, int pc);
346
347 void trace_graph_return(struct ftrace_graph_ret *trace);
348 int trace_graph_entry(struct ftrace_graph_ent *trace);
349 void set_graph_array(struct trace_array *tr);
350
351 void tracing_start_cmdline_record(void);
352 void tracing_stop_cmdline_record(void);
353 void tracing_sched_switch_assign_trace(struct trace_array *tr);
354 void tracing_stop_sched_switch_record(void);
355 void tracing_start_sched_switch_record(void);
356 int register_tracer(struct tracer *type);
357 void unregister_tracer(struct tracer *type);
358 int is_tracing_stopped(void);
359
360 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
361
362 #ifdef CONFIG_TRACER_MAX_TRACE
363 extern unsigned long tracing_max_latency;
364 extern unsigned long tracing_thresh;
365
366 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
367 void update_max_tr_single(struct trace_array *tr,
368                           struct task_struct *tsk, int cpu);
369 #endif /* CONFIG_TRACER_MAX_TRACE */
370
371 #ifdef CONFIG_STACKTRACE
372 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
373                         int skip, int pc);
374
375 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
376                             int pc);
377
378 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
379                    int pc);
380 #else
381 static inline void ftrace_trace_stack(struct trace_array *tr,
382                                       unsigned long flags, int skip, int pc)
383 {
384 }
385
386 static inline void ftrace_trace_userstack(struct trace_array *tr,
387                                           unsigned long flags, int pc)
388 {
389 }
390
391 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
392                                  int skip, int pc)
393 {
394 }
395 #endif /* CONFIG_STACKTRACE */
396
397 extern cycle_t ftrace_now(int cpu);
398
399 extern void trace_find_cmdline(int pid, char comm[]);
400
401 #ifdef CONFIG_DYNAMIC_FTRACE
402 extern unsigned long ftrace_update_tot_cnt;
403 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
404 extern int DYN_FTRACE_TEST_NAME(void);
405 #endif
406
407 extern int ring_buffer_expanded;
408 extern bool tracing_selftest_disabled;
409 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
410
411 #ifdef CONFIG_FTRACE_STARTUP_TEST
412 extern int trace_selftest_startup_function(struct tracer *trace,
413                                            struct trace_array *tr);
414 extern int trace_selftest_startup_function_graph(struct tracer *trace,
415                                                  struct trace_array *tr);
416 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
417                                           struct trace_array *tr);
418 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
419                                              struct trace_array *tr);
420 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
421                                                  struct trace_array *tr);
422 extern int trace_selftest_startup_wakeup(struct tracer *trace,
423                                          struct trace_array *tr);
424 extern int trace_selftest_startup_nop(struct tracer *trace,
425                                          struct trace_array *tr);
426 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
427                                                struct trace_array *tr);
428 extern int trace_selftest_startup_sysprof(struct tracer *trace,
429                                                struct trace_array *tr);
430 extern int trace_selftest_startup_branch(struct tracer *trace,
431                                          struct trace_array *tr);
432 extern int trace_selftest_startup_hw_branches(struct tracer *trace,
433                                               struct trace_array *tr);
434 #endif /* CONFIG_FTRACE_STARTUP_TEST */
435
436 extern void *head_page(struct trace_array_cpu *data);
437 extern unsigned long long ns2usecs(cycle_t nsec);
438 extern int
439 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
440 extern int
441 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
442 extern int
443 trace_array_vprintk(struct trace_array *tr,
444                     unsigned long ip, const char *fmt, va_list args);
445 int trace_array_printk(struct trace_array *tr,
446                        unsigned long ip, const char *fmt, ...);
447
448 extern unsigned long trace_flags;
449
450 extern int trace_clock_id;
451
452 /* Standard output formatting function used for function return traces */
453 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
454 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
455 extern enum print_line_t
456 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
457
458 #ifdef CONFIG_DYNAMIC_FTRACE
459 /* TODO: make this variable */
460 #define FTRACE_GRAPH_MAX_FUNCS          32
461 extern int ftrace_graph_count;
462 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
463
464 static inline int ftrace_graph_addr(unsigned long addr)
465 {
466         int i;
467
468         if (!ftrace_graph_count || test_tsk_trace_graph(current))
469                 return 1;
470
471         for (i = 0; i < ftrace_graph_count; i++) {
472                 if (addr == ftrace_graph_funcs[i])
473                         return 1;
474         }
475
476         return 0;
477 }
478 #else
479 static inline int ftrace_trace_addr(unsigned long addr)
480 {
481         return 1;
482 }
483 static inline int ftrace_graph_addr(unsigned long addr)
484 {
485         return 1;
486 }
487 #endif /* CONFIG_DYNAMIC_FTRACE */
488 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
489 static inline enum print_line_t
490 print_graph_function(struct trace_iterator *iter)
491 {
492         return TRACE_TYPE_UNHANDLED;
493 }
494 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
495
496 extern struct pid *ftrace_pid_trace;
497
498 #ifdef CONFIG_FUNCTION_TRACER
499 static inline int ftrace_trace_task(struct task_struct *task)
500 {
501         if (!ftrace_pid_trace)
502                 return 1;
503
504         return test_tsk_trace_trace(task);
505 }
506 #else
507 static inline int ftrace_trace_task(struct task_struct *task)
508 {
509         return 1;
510 }
511 #endif
512
513 /*
514  * struct trace_parser - servers for reading the user input separated by spaces
515  * @cont: set if the input is not complete - no final space char was found
516  * @buffer: holds the parsed user input
517  * @idx: user input lenght
518  * @size: buffer size
519  */
520 struct trace_parser {
521         bool            cont;
522         char            *buffer;
523         unsigned        idx;
524         unsigned        size;
525 };
526
527 static inline bool trace_parser_loaded(struct trace_parser *parser)
528 {
529         return (parser->idx != 0);
530 }
531
532 static inline bool trace_parser_cont(struct trace_parser *parser)
533 {
534         return parser->cont;
535 }
536
537 static inline void trace_parser_clear(struct trace_parser *parser)
538 {
539         parser->cont = false;
540         parser->idx = 0;
541 }
542
543 extern int trace_parser_get_init(struct trace_parser *parser, int size);
544 extern void trace_parser_put(struct trace_parser *parser);
545 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
546         size_t cnt, loff_t *ppos);
547
548 /*
549  * trace_iterator_flags is an enumeration that defines bit
550  * positions into trace_flags that controls the output.
551  *
552  * NOTE: These bits must match the trace_options array in
553  *       trace.c.
554  */
555 enum trace_iterator_flags {
556         TRACE_ITER_PRINT_PARENT         = 0x01,
557         TRACE_ITER_SYM_OFFSET           = 0x02,
558         TRACE_ITER_SYM_ADDR             = 0x04,
559         TRACE_ITER_VERBOSE              = 0x08,
560         TRACE_ITER_RAW                  = 0x10,
561         TRACE_ITER_HEX                  = 0x20,
562         TRACE_ITER_BIN                  = 0x40,
563         TRACE_ITER_BLOCK                = 0x80,
564         TRACE_ITER_STACKTRACE           = 0x100,
565         TRACE_ITER_SCHED_TREE           = 0x200,
566         TRACE_ITER_PRINTK               = 0x400,
567         TRACE_ITER_PREEMPTONLY          = 0x800,
568         TRACE_ITER_BRANCH               = 0x1000,
569         TRACE_ITER_ANNOTATE             = 0x2000,
570         TRACE_ITER_USERSTACKTRACE       = 0x4000,
571         TRACE_ITER_SYM_USEROBJ          = 0x8000,
572         TRACE_ITER_PRINTK_MSGONLY       = 0x10000,
573         TRACE_ITER_CONTEXT_INFO         = 0x20000, /* Print pid/cpu/time */
574         TRACE_ITER_LATENCY_FMT          = 0x40000,
575         TRACE_ITER_SLEEP_TIME           = 0x80000,
576         TRACE_ITER_GRAPH_TIME           = 0x100000,
577 };
578
579 /*
580  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
581  * control the output of kernel symbols.
582  */
583 #define TRACE_ITER_SYM_MASK \
584         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
585
586 extern struct tracer nop_trace;
587
588 /**
589  * ftrace_preempt_disable - disable preemption scheduler safe
590  *
591  * When tracing can happen inside the scheduler, there exists
592  * cases that the tracing might happen before the need_resched
593  * flag is checked. If this happens and the tracer calls
594  * preempt_enable (after a disable), a schedule might take place
595  * causing an infinite recursion.
596  *
597  * To prevent this, we read the need_resched flag before
598  * disabling preemption. When we want to enable preemption we
599  * check the flag, if it is set, then we call preempt_enable_no_resched.
600  * Otherwise, we call preempt_enable.
601  *
602  * The rational for doing the above is that if need_resched is set
603  * and we have yet to reschedule, we are either in an atomic location
604  * (where we do not need to check for scheduling) or we are inside
605  * the scheduler and do not want to resched.
606  */
607 static inline int ftrace_preempt_disable(void)
608 {
609         int resched;
610
611         resched = need_resched();
612         preempt_disable_notrace();
613
614         return resched;
615 }
616
617 /**
618  * ftrace_preempt_enable - enable preemption scheduler safe
619  * @resched: the return value from ftrace_preempt_disable
620  *
621  * This is a scheduler safe way to enable preemption and not miss
622  * any preemption checks. The disabled saved the state of preemption.
623  * If resched is set, then we are either inside an atomic or
624  * are inside the scheduler (we would have already scheduled
625  * otherwise). In this case, we do not want to call normal
626  * preempt_enable, but preempt_enable_no_resched instead.
627  */
628 static inline void ftrace_preempt_enable(int resched)
629 {
630         if (resched)
631                 preempt_enable_no_resched_notrace();
632         else
633                 preempt_enable_notrace();
634 }
635
636 #ifdef CONFIG_BRANCH_TRACER
637 extern int enable_branch_tracing(struct trace_array *tr);
638 extern void disable_branch_tracing(void);
639 static inline int trace_branch_enable(struct trace_array *tr)
640 {
641         if (trace_flags & TRACE_ITER_BRANCH)
642                 return enable_branch_tracing(tr);
643         return 0;
644 }
645 static inline void trace_branch_disable(void)
646 {
647         /* due to races, always disable */
648         disable_branch_tracing();
649 }
650 #else
651 static inline int trace_branch_enable(struct trace_array *tr)
652 {
653         return 0;
654 }
655 static inline void trace_branch_disable(void)
656 {
657 }
658 #endif /* CONFIG_BRANCH_TRACER */
659
660 /* set ring buffers to default size if not already done so */
661 int tracing_update_buffers(void);
662
663 /* trace event type bit fields, not numeric */
664 enum {
665         TRACE_EVENT_TYPE_PRINTF         = 1,
666         TRACE_EVENT_TYPE_RAW            = 2,
667 };
668
669 struct ftrace_event_field {
670         struct list_head        link;
671         char                    *name;
672         char                    *type;
673         int                     filter_type;
674         int                     offset;
675         int                     size;
676         int                     is_signed;
677 };
678
679 struct event_filter {
680         int                     n_preds;
681         struct filter_pred      **preds;
682         char                    *filter_string;
683         bool                    no_reset;
684 };
685
686 struct event_subsystem {
687         struct list_head        list;
688         const char              *name;
689         struct dentry           *entry;
690         struct event_filter     *filter;
691         int                     nr_events;
692 };
693
694 struct filter_pred;
695
696 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
697                                  int val1, int val2);
698
699 struct filter_pred {
700         filter_pred_fn_t fn;
701         u64 val;
702         char str_val[MAX_FILTER_STR_VAL];
703         int str_len;
704         char *field_name;
705         int offset;
706         int not;
707         int op;
708         int pop_n;
709 };
710
711 extern void print_event_filter(struct ftrace_event_call *call,
712                                struct trace_seq *s);
713 extern int apply_event_filter(struct ftrace_event_call *call,
714                               char *filter_string);
715 extern int apply_subsystem_event_filter(struct event_subsystem *system,
716                                         char *filter_string);
717 extern void print_subsystem_event_filter(struct event_subsystem *system,
718                                          struct trace_seq *s);
719 extern int filter_assign_type(const char *type);
720
721 static inline int
722 filter_check_discard(struct ftrace_event_call *call, void *rec,
723                      struct ring_buffer *buffer,
724                      struct ring_buffer_event *event)
725 {
726         if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) {
727                 ring_buffer_discard_commit(buffer, event);
728                 return 1;
729         }
730
731         return 0;
732 }
733
734 extern struct mutex event_mutex;
735 extern struct list_head ftrace_events;
736
737 extern const char *__start___trace_bprintk_fmt[];
738 extern const char *__stop___trace_bprintk_fmt[];
739
740 #undef TRACE_EVENT_FORMAT
741 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
742         extern struct ftrace_event_call event_##call;
743 #undef TRACE_EVENT_FORMAT_NOFILTER
744 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
745 #include "trace_event_types.h"
746
747 #endif /* _LINUX_KERNEL_TRACE_H */