cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags
[pandora-kernel.git] / include / linux / ftrace_event.h
1
2 #ifndef _LINUX_FTRACE_EVENT_H
3 #define _LINUX_FTRACE_EVENT_H
4
5 #include <linux/ring_buffer.h>
6 #include <linux/trace_seq.h>
7 #include <linux/percpu.h>
8 #include <linux/hardirq.h>
9 #include <linux/perf_event.h>
10 #include <linux/tracepoint.h>
11
12 struct trace_array;
13 struct trace_buffer;
14 struct tracer;
15 struct dentry;
16
17 struct trace_print_flags {
18         unsigned long           mask;
19         const char              *name;
20 };
21
22 struct trace_print_flags_u64 {
23         unsigned long long      mask;
24         const char              *name;
25 };
26
27 const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
28                                    unsigned long flags,
29                                    const struct trace_print_flags *flag_array);
30
31 const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
32                                      const struct trace_print_flags *symbol_array);
33
34 #if BITS_PER_LONG == 32
35 const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
36                                          unsigned long long val,
37                                          const struct trace_print_flags_u64
38                                                                  *symbol_array);
39 #endif
40
41 const char *ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
42                                      unsigned int bitmask_size);
43
44 const char *ftrace_print_hex_seq(struct trace_seq *p,
45                                  const unsigned char *buf, int len);
46
47 struct trace_iterator;
48 struct trace_event;
49
50 int ftrace_raw_output_prep(struct trace_iterator *iter,
51                            struct trace_event *event);
52
53 /*
54  * The trace entry - the most basic unit of tracing. This is what
55  * is printed in the end as a single line in the trace output, such as:
56  *
57  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
58  */
59 struct trace_entry {
60         unsigned short          type;
61         unsigned char           flags;
62         unsigned char           preempt_count;
63         int                     pid;
64 };
65
66 #define FTRACE_MAX_EVENT                                                \
67         ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
68
69 /*
70  * Trace iterator - used by printout routines who present trace
71  * results to users and which routines might sleep, etc:
72  */
73 struct trace_iterator {
74         struct trace_array      *tr;
75         struct tracer           *trace;
76         struct trace_buffer     *trace_buffer;
77         void                    *private;
78         int                     cpu_file;
79         struct mutex            mutex;
80         struct ring_buffer_iter **buffer_iter;
81         unsigned long           iter_flags;
82
83         /* trace_seq for __print_flags() and __print_symbolic() etc. */
84         struct trace_seq        tmp_seq;
85
86         cpumask_var_t           started;
87
88         /* it's true when current open file is snapshot */
89         bool                    snapshot;
90
91         /* The below is zeroed out in pipe_read */
92         struct trace_seq        seq;
93         struct trace_entry      *ent;
94         unsigned long           lost_events;
95         int                     leftover;
96         int                     ent_size;
97         int                     cpu;
98         u64                     ts;
99
100         loff_t                  pos;
101         long                    idx;
102
103         /* All new field here will be zeroed out in pipe_read */
104 };
105
106 enum trace_iter_flags {
107         TRACE_FILE_LAT_FMT      = 1,
108         TRACE_FILE_ANNOTATE     = 2,
109         TRACE_FILE_TIME_IN_NS   = 4,
110 };
111
112
113 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
114                                       int flags, struct trace_event *event);
115
116 struct trace_event_functions {
117         trace_print_func        trace;
118         trace_print_func        raw;
119         trace_print_func        hex;
120         trace_print_func        binary;
121 };
122
123 struct trace_event {
124         struct hlist_node               node;
125         struct list_head                list;
126         int                             type;
127         struct trace_event_functions    *funcs;
128 };
129
130 extern int register_ftrace_event(struct trace_event *event);
131 extern int unregister_ftrace_event(struct trace_event *event);
132
133 /* Return values for print_line callback */
134 enum print_line_t {
135         TRACE_TYPE_PARTIAL_LINE = 0,    /* Retry after flushing the seq */
136         TRACE_TYPE_HANDLED      = 1,
137         TRACE_TYPE_UNHANDLED    = 2,    /* Relay to other output functions */
138         TRACE_TYPE_NO_CONSUME   = 3     /* Handled but ask to not consume */
139 };
140
141 void tracing_generic_entry_update(struct trace_entry *entry,
142                                   unsigned long flags,
143                                   int pc);
144 struct ftrace_event_file;
145
146 struct ring_buffer_event *
147 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
148                                 struct ftrace_event_file *ftrace_file,
149                                 int type, unsigned long len,
150                                 unsigned long flags, int pc);
151 struct ring_buffer_event *
152 trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
153                                   int type, unsigned long len,
154                                   unsigned long flags, int pc);
155 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
156                                         struct ring_buffer_event *event,
157                                         unsigned long flags, int pc);
158 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
159                                 struct ring_buffer_event *event,
160                                 unsigned long flags, int pc);
161 void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
162                                      struct ring_buffer_event *event,
163                                      unsigned long flags, int pc,
164                                      struct pt_regs *regs);
165 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
166                                          struct ring_buffer_event *event);
167
168 void tracing_record_cmdline(struct task_struct *tsk);
169
170 int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...);
171
172 struct event_filter;
173
174 enum trace_reg {
175         TRACE_REG_REGISTER,
176         TRACE_REG_UNREGISTER,
177 #ifdef CONFIG_PERF_EVENTS
178         TRACE_REG_PERF_REGISTER,
179         TRACE_REG_PERF_UNREGISTER,
180         TRACE_REG_PERF_OPEN,
181         TRACE_REG_PERF_CLOSE,
182         TRACE_REG_PERF_ADD,
183         TRACE_REG_PERF_DEL,
184 #endif
185 };
186
187 struct ftrace_event_call;
188
189 struct ftrace_event_class {
190         char                    *system;
191         void                    *probe;
192 #ifdef CONFIG_PERF_EVENTS
193         void                    *perf_probe;
194 #endif
195         int                     (*reg)(struct ftrace_event_call *event,
196                                        enum trace_reg type, void *data);
197         int                     (*define_fields)(struct ftrace_event_call *);
198         struct list_head        *(*get_fields)(struct ftrace_event_call *);
199         struct list_head        fields;
200         int                     (*raw_init)(struct ftrace_event_call *);
201 };
202
203 extern int ftrace_event_reg(struct ftrace_event_call *event,
204                             enum trace_reg type, void *data);
205
206 int ftrace_output_event(struct trace_iterator *iter, struct ftrace_event_call *event,
207                         char *fmt, ...);
208
209 int ftrace_event_define_field(struct ftrace_event_call *call,
210                               char *type, int len, char *item, int offset,
211                               int field_size, int sign, int filter);
212
213 struct ftrace_event_buffer {
214         struct ring_buffer              *buffer;
215         struct ring_buffer_event        *event;
216         struct ftrace_event_file        *ftrace_file;
217         void                            *entry;
218         unsigned long                   flags;
219         int                             pc;
220 };
221
222 void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer,
223                                   struct ftrace_event_file *ftrace_file,
224                                   unsigned long len);
225
226 void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer);
227
228 int ftrace_event_define_field(struct ftrace_event_call *call,
229                               char *type, int len, char *item, int offset,
230                               int field_size, int sign, int filter);
231
232 enum {
233         TRACE_EVENT_FL_FILTERED_BIT,
234         TRACE_EVENT_FL_CAP_ANY_BIT,
235         TRACE_EVENT_FL_NO_SET_FILTER_BIT,
236         TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
237         TRACE_EVENT_FL_WAS_ENABLED_BIT,
238         TRACE_EVENT_FL_USE_CALL_FILTER_BIT,
239         TRACE_EVENT_FL_TRACEPOINT_BIT,
240 };
241
242 /*
243  * Event flags:
244  *  FILTERED      - The event has a filter attached
245  *  CAP_ANY       - Any user can enable for perf
246  *  NO_SET_FILTER - Set when filter has error and is to be ignored
247  *  IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
248  *  WAS_ENABLED   - Set and stays set when an event was ever enabled
249  *                    (used for module unloading, if a module event is enabled,
250  *                     it is best to clear the buffers that used it).
251  *  USE_CALL_FILTER - For ftrace internal events, don't use file filter
252  *  TRACEPOINT    - Event is a tracepoint
253  */
254 enum {
255         TRACE_EVENT_FL_FILTERED         = (1 << TRACE_EVENT_FL_FILTERED_BIT),
256         TRACE_EVENT_FL_CAP_ANY          = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
257         TRACE_EVENT_FL_NO_SET_FILTER    = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
258         TRACE_EVENT_FL_IGNORE_ENABLE    = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
259         TRACE_EVENT_FL_WAS_ENABLED      = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
260         TRACE_EVENT_FL_USE_CALL_FILTER  = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT),
261         TRACE_EVENT_FL_TRACEPOINT       = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
262 };
263
264 struct ftrace_event_call {
265         struct list_head        list;
266         struct ftrace_event_class *class;
267         union {
268                 char                    *name;
269                 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
270                 struct tracepoint       *tp;
271         };
272         struct trace_event      event;
273         const char              *print_fmt;
274         struct event_filter     *filter;
275         void                    *mod;
276         void                    *data;
277         /*
278          *   bit 0:             filter_active
279          *   bit 1:             allow trace by non root (cap any)
280          *   bit 2:             failed to apply filter
281          *   bit 3:             ftrace internal event (do not enable)
282          *   bit 4:             Event was enabled by module
283          *   bit 5:             use call filter rather than file filter
284          *   bit 6:             Event is a tracepoint
285          */
286         int                     flags; /* static flags of different events */
287
288 #ifdef CONFIG_PERF_EVENTS
289         int                             perf_refcount;
290         struct hlist_head __percpu      *perf_events;
291
292         int     (*perf_perm)(struct ftrace_event_call *,
293                              struct perf_event *);
294 #endif
295 };
296
297 static inline const char *
298 ftrace_event_name(struct ftrace_event_call *call)
299 {
300         if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
301                 return call->tp ? call->tp->name : NULL;
302         else
303                 return call->name;
304 }
305
306 struct trace_array;
307 struct ftrace_subsystem_dir;
308
309 enum {
310         FTRACE_EVENT_FL_ENABLED_BIT,
311         FTRACE_EVENT_FL_RECORDED_CMD_BIT,
312         FTRACE_EVENT_FL_FILTERED_BIT,
313         FTRACE_EVENT_FL_NO_SET_FILTER_BIT,
314         FTRACE_EVENT_FL_SOFT_MODE_BIT,
315         FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
316         FTRACE_EVENT_FL_TRIGGER_MODE_BIT,
317         FTRACE_EVENT_FL_TRIGGER_COND_BIT,
318 };
319
320 /*
321  * Ftrace event file flags:
322  *  ENABLED       - The event is enabled
323  *  RECORDED_CMD  - The comms should be recorded at sched_switch
324  *  FILTERED      - The event has a filter attached
325  *  NO_SET_FILTER - Set when filter has error and is to be ignored
326  *  SOFT_MODE     - The event is enabled/disabled by SOFT_DISABLED
327  *  SOFT_DISABLED - When set, do not trace the event (even though its
328  *                   tracepoint may be enabled)
329  *  TRIGGER_MODE  - When set, invoke the triggers associated with the event
330  *  TRIGGER_COND  - When set, one or more triggers has an associated filter
331  */
332 enum {
333         FTRACE_EVENT_FL_ENABLED         = (1 << FTRACE_EVENT_FL_ENABLED_BIT),
334         FTRACE_EVENT_FL_RECORDED_CMD    = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT),
335         FTRACE_EVENT_FL_FILTERED        = (1 << FTRACE_EVENT_FL_FILTERED_BIT),
336         FTRACE_EVENT_FL_NO_SET_FILTER   = (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT),
337         FTRACE_EVENT_FL_SOFT_MODE       = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT),
338         FTRACE_EVENT_FL_SOFT_DISABLED   = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT),
339         FTRACE_EVENT_FL_TRIGGER_MODE    = (1 << FTRACE_EVENT_FL_TRIGGER_MODE_BIT),
340         FTRACE_EVENT_FL_TRIGGER_COND    = (1 << FTRACE_EVENT_FL_TRIGGER_COND_BIT),
341 };
342
343 struct ftrace_event_file {
344         struct list_head                list;
345         struct ftrace_event_call        *event_call;
346         struct event_filter             *filter;
347         struct dentry                   *dir;
348         struct trace_array              *tr;
349         struct ftrace_subsystem_dir     *system;
350         struct list_head                triggers;
351
352         /*
353          * 32 bit flags:
354          *   bit 0:             enabled
355          *   bit 1:             enabled cmd record
356          *   bit 2:             enable/disable with the soft disable bit
357          *   bit 3:             soft disabled
358          *   bit 4:             trigger enabled
359          *
360          * Note: The bits must be set atomically to prevent races
361          * from other writers. Reads of flags do not need to be in
362          * sync as they occur in critical sections. But the way flags
363          * is currently used, these changes do not affect the code
364          * except that when a change is made, it may have a slight
365          * delay in propagating the changes to other CPUs due to
366          * caching and such. Which is mostly OK ;-)
367          */
368         unsigned long           flags;
369         atomic_t                sm_ref; /* soft-mode reference counter */
370         atomic_t                tm_ref; /* trigger-mode reference counter */
371 };
372
373 #define __TRACE_EVENT_FLAGS(name, value)                                \
374         static int __init trace_init_flags_##name(void)                 \
375         {                                                               \
376                 event_##name.flags |= value;                            \
377                 return 0;                                               \
378         }                                                               \
379         early_initcall(trace_init_flags_##name);
380
381 #define __TRACE_EVENT_PERF_PERM(name, expr...)                          \
382         static int perf_perm_##name(struct ftrace_event_call *tp_event, \
383                                     struct perf_event *p_event)         \
384         {                                                               \
385                 return ({ expr; });                                     \
386         }                                                               \
387         static int __init trace_init_perf_perm_##name(void)             \
388         {                                                               \
389                 event_##name.perf_perm = &perf_perm_##name;             \
390                 return 0;                                               \
391         }                                                               \
392         early_initcall(trace_init_perf_perm_##name);
393
394 #define PERF_MAX_TRACE_SIZE     2048
395
396 #define MAX_FILTER_STR_VAL      256     /* Should handle KSYM_SYMBOL_LEN */
397
398 enum event_trigger_type {
399         ETT_NONE                = (0),
400         ETT_TRACE_ONOFF         = (1 << 0),
401         ETT_SNAPSHOT            = (1 << 1),
402         ETT_STACKTRACE          = (1 << 2),
403         ETT_EVENT_ENABLE        = (1 << 3),
404 };
405
406 extern int filter_match_preds(struct event_filter *filter, void *rec);
407
408 extern int filter_check_discard(struct ftrace_event_file *file, void *rec,
409                                 struct ring_buffer *buffer,
410                                 struct ring_buffer_event *event);
411 extern int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
412                                      struct ring_buffer *buffer,
413                                      struct ring_buffer_event *event);
414 extern enum event_trigger_type event_triggers_call(struct ftrace_event_file *file,
415                                                    void *rec);
416 extern void event_triggers_post_call(struct ftrace_event_file *file,
417                                      enum event_trigger_type tt);
418
419 /**
420  * ftrace_trigger_soft_disabled - do triggers and test if soft disabled
421  * @file: The file pointer of the event to test
422  *
423  * If any triggers without filters are attached to this event, they
424  * will be called here. If the event is soft disabled and has no
425  * triggers that require testing the fields, it will return true,
426  * otherwise false.
427  */
428 static inline bool
429 ftrace_trigger_soft_disabled(struct ftrace_event_file *file)
430 {
431         unsigned long eflags = file->flags;
432
433         if (!(eflags & FTRACE_EVENT_FL_TRIGGER_COND)) {
434                 if (eflags & FTRACE_EVENT_FL_TRIGGER_MODE)
435                         event_triggers_call(file, NULL);
436                 if (eflags & FTRACE_EVENT_FL_SOFT_DISABLED)
437                         return true;
438         }
439         return false;
440 }
441
442 /*
443  * Helper function for event_trigger_unlock_commit{_regs}().
444  * If there are event triggers attached to this event that requires
445  * filtering against its fields, then they wil be called as the
446  * entry already holds the field information of the current event.
447  *
448  * It also checks if the event should be discarded or not.
449  * It is to be discarded if the event is soft disabled and the
450  * event was only recorded to process triggers, or if the event
451  * filter is active and this event did not match the filters.
452  *
453  * Returns true if the event is discarded, false otherwise.
454  */
455 static inline bool
456 __event_trigger_test_discard(struct ftrace_event_file *file,
457                              struct ring_buffer *buffer,
458                              struct ring_buffer_event *event,
459                              void *entry,
460                              enum event_trigger_type *tt)
461 {
462         unsigned long eflags = file->flags;
463
464         if (eflags & FTRACE_EVENT_FL_TRIGGER_COND)
465                 *tt = event_triggers_call(file, entry);
466
467         if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags))
468                 ring_buffer_discard_commit(buffer, event);
469         else if (!filter_check_discard(file, entry, buffer, event))
470                 return false;
471
472         return true;
473 }
474
475 /**
476  * event_trigger_unlock_commit - handle triggers and finish event commit
477  * @file: The file pointer assoctiated to the event
478  * @buffer: The ring buffer that the event is being written to
479  * @event: The event meta data in the ring buffer
480  * @entry: The event itself
481  * @irq_flags: The state of the interrupts at the start of the event
482  * @pc: The state of the preempt count at the start of the event.
483  *
484  * This is a helper function to handle triggers that require data
485  * from the event itself. It also tests the event against filters and
486  * if the event is soft disabled and should be discarded.
487  */
488 static inline void
489 event_trigger_unlock_commit(struct ftrace_event_file *file,
490                             struct ring_buffer *buffer,
491                             struct ring_buffer_event *event,
492                             void *entry, unsigned long irq_flags, int pc)
493 {
494         enum event_trigger_type tt = ETT_NONE;
495
496         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
497                 trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
498
499         if (tt)
500                 event_triggers_post_call(file, tt);
501 }
502
503 /**
504  * event_trigger_unlock_commit_regs - handle triggers and finish event commit
505  * @file: The file pointer assoctiated to the event
506  * @buffer: The ring buffer that the event is being written to
507  * @event: The event meta data in the ring buffer
508  * @entry: The event itself
509  * @irq_flags: The state of the interrupts at the start of the event
510  * @pc: The state of the preempt count at the start of the event.
511  *
512  * This is a helper function to handle triggers that require data
513  * from the event itself. It also tests the event against filters and
514  * if the event is soft disabled and should be discarded.
515  *
516  * Same as event_trigger_unlock_commit() but calls
517  * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
518  */
519 static inline void
520 event_trigger_unlock_commit_regs(struct ftrace_event_file *file,
521                                  struct ring_buffer *buffer,
522                                  struct ring_buffer_event *event,
523                                  void *entry, unsigned long irq_flags, int pc,
524                                  struct pt_regs *regs)
525 {
526         enum event_trigger_type tt = ETT_NONE;
527
528         if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
529                 trace_buffer_unlock_commit_regs(buffer, event,
530                                                 irq_flags, pc, regs);
531
532         if (tt)
533                 event_triggers_post_call(file, tt);
534 }
535
536 enum {
537         FILTER_OTHER = 0,
538         FILTER_STATIC_STRING,
539         FILTER_DYN_STRING,
540         FILTER_PTR_STRING,
541         FILTER_TRACE_FN,
542 };
543
544 extern int trace_event_raw_init(struct ftrace_event_call *call);
545 extern int trace_define_field(struct ftrace_event_call *call, const char *type,
546                               const char *name, int offset, int size,
547                               int is_signed, int filter_type);
548 extern int trace_add_event_call(struct ftrace_event_call *call);
549 extern int trace_remove_event_call(struct ftrace_event_call *call);
550
551 #define is_signed_type(type)    (((type)(-1)) < (type)1)
552
553 int trace_set_clr_event(const char *system, const char *event, int set);
554
555 /*
556  * The double __builtin_constant_p is because gcc will give us an error
557  * if we try to allocate the static variable to fmt if it is not a
558  * constant. Even with the outer if statement optimizing out.
559  */
560 #define event_trace_printk(ip, fmt, args...)                            \
561 do {                                                                    \
562         __trace_printk_check_format(fmt, ##args);                       \
563         tracing_record_cmdline(current);                                \
564         if (__builtin_constant_p(fmt)) {                                \
565                 static const char *trace_printk_fmt                     \
566                   __attribute__((section("__trace_printk_fmt"))) =      \
567                         __builtin_constant_p(fmt) ? fmt : NULL;         \
568                                                                         \
569                 __trace_bprintk(ip, trace_printk_fmt, ##args);          \
570         } else                                                          \
571                 __trace_printk(ip, fmt, ##args);                        \
572 } while (0)
573
574 #ifdef CONFIG_PERF_EVENTS
575 struct perf_event;
576
577 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
578
579 extern int  perf_trace_init(struct perf_event *event);
580 extern void perf_trace_destroy(struct perf_event *event);
581 extern int  perf_trace_add(struct perf_event *event, int flags);
582 extern void perf_trace_del(struct perf_event *event, int flags);
583 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
584                                      char *filter_str);
585 extern void ftrace_profile_free_filter(struct perf_event *event);
586 extern void *perf_trace_buf_prepare(int size, unsigned short type,
587                                     struct pt_regs *regs, int *rctxp);
588
589 static inline void
590 perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
591                        u64 count, struct pt_regs *regs, void *head,
592                        struct task_struct *task)
593 {
594         perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
595 }
596 #endif
597
598 #endif /* _LINUX_FTRACE_EVENT_H */