db6b83edd49bf62851953de5dafd9663cdc8f389
[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 <trace/power.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_HW_BRANCHES,
38         TRACE_KMEM_ALLOC,
39         TRACE_KMEM_FREE,
40         TRACE_POWER,
41         TRACE_BLK,
42
43         __TRACE_LAST_TYPE,
44 };
45
46 enum kmemtrace_type_id {
47         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
48         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
49         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
50 };
51
52 extern struct tracer boot_tracer;
53
54 #undef __field
55 #define __field(type, item)             type    item;
56
57 #undef __field_struct
58 #define __field_struct(type, item)      __field(type, item)
59
60 #undef __field_desc
61 #define __field_desc(type, container, item)
62
63 #undef __array
64 #define __array(type, item, size)       type    item[size];
65
66 #undef __array_desc
67 #define __array_desc(type, container, item, size)
68
69 #undef __dynamic_array
70 #define __dynamic_array(type, item)     type    item[];
71
72 #undef F_STRUCT
73 #define F_STRUCT(args...)               args
74
75 #undef FTRACE_ENTRY
76 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
77         struct struct_name {                                    \
78                 struct trace_entry      ent;                    \
79                 tstruct                                         \
80         }
81
82 #undef TP_ARGS
83 #define TP_ARGS(args...)        args
84
85 #undef FTRACE_ENTRY_DUP
86 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
87
88 #include "trace_entries.h"
89
90 /*
91  * syscalls are special, and need special handling, this is why
92  * they are not included in trace_entries.h
93  */
94 struct syscall_trace_enter {
95         struct trace_entry      ent;
96         int                     nr;
97         unsigned long           args[];
98 };
99
100 struct syscall_trace_exit {
101         struct trace_entry      ent;
102         int                     nr;
103         unsigned long           ret;
104 };
105
106 /*
107  * trace_flag_type is an enumeration that holds different
108  * states when a trace occurs. These are:
109  *  IRQS_OFF            - interrupts were disabled
110  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
111  *  NEED_RESCHED        - reschedule is requested
112  *  HARDIRQ             - inside an interrupt handler
113  *  SOFTIRQ             - inside a softirq handler
114  */
115 enum trace_flag_type {
116         TRACE_FLAG_IRQS_OFF             = 0x01,
117         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
118         TRACE_FLAG_NEED_RESCHED         = 0x04,
119         TRACE_FLAG_HARDIRQ              = 0x08,
120         TRACE_FLAG_SOFTIRQ              = 0x10,
121 };
122
123 #define TRACE_BUF_SIZE          1024
124
125 /*
126  * The CPU trace array - it consists of thousands of trace entries
127  * plus some other descriptor data: (for example which task started
128  * the trace, etc.)
129  */
130 struct trace_array_cpu {
131         atomic_t                disabled;
132         void                    *buffer_page;   /* ring buffer spare */
133
134         unsigned long           saved_latency;
135         unsigned long           critical_start;
136         unsigned long           critical_end;
137         unsigned long           critical_sequence;
138         unsigned long           nice;
139         unsigned long           policy;
140         unsigned long           rt_priority;
141         unsigned long           skipped_entries;
142         cycle_t                 preempt_timestamp;
143         pid_t                   pid;
144         uid_t                   uid;
145         char                    comm[TASK_COMM_LEN];
146 };
147
148 /*
149  * The trace array - an array of per-CPU trace arrays. This is the
150  * highest level data structure that individual tracers deal with.
151  * They have on/off state as well:
152  */
153 struct trace_array {
154         struct ring_buffer      *buffer;
155         unsigned long           entries;
156         int                     cpu;
157         cycle_t                 time_start;
158         struct task_struct      *waiter;
159         struct trace_array_cpu  *data[NR_CPUS];
160 };
161
162 #define FTRACE_CMP_TYPE(var, type) \
163         __builtin_types_compatible_p(typeof(var), type *)
164
165 #undef IF_ASSIGN
166 #define IF_ASSIGN(var, entry, etype, id)                \
167         if (FTRACE_CMP_TYPE(var, etype)) {              \
168                 var = (typeof(var))(entry);             \
169                 WARN_ON(id && (entry)->type != id);     \
170                 break;                                  \
171         }
172
173 /* Will cause compile errors if type is not found. */
174 extern void __ftrace_bad_type(void);
175
176 /*
177  * The trace_assign_type is a verifier that the entry type is
178  * the same as the type being assigned. To add new types simply
179  * add a line with the following format:
180  *
181  * IF_ASSIGN(var, ent, type, id);
182  *
183  *  Where "type" is the trace type that includes the trace_entry
184  *  as the "ent" item. And "id" is the trace identifier that is
185  *  used in the trace_type enum.
186  *
187  *  If the type can have more than one id, then use zero.
188  */
189 #define trace_assign_type(var, ent)                                     \
190         do {                                                            \
191                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
192                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
193                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
194                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
195                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
196                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
197                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
198                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
199                           TRACE_MMIO_RW);                               \
200                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
201                           TRACE_MMIO_MAP);                              \
202                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
203                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
204                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
205                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
206                           TRACE_GRAPH_ENT);             \
207                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
208                           TRACE_GRAPH_RET);             \
209                 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
210                 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
211                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
212                           TRACE_KMEM_ALLOC);    \
213                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
214                           TRACE_KMEM_FREE);     \
215                 __ftrace_bad_type();                                    \
216         } while (0)
217
218 /*
219  * An option specific to a tracer. This is a boolean value.
220  * The bit is the bit index that sets its value on the
221  * flags value in struct tracer_flags.
222  */
223 struct tracer_opt {
224         const char      *name; /* Will appear on the trace_options file */
225         u32             bit; /* Mask assigned in val field in tracer_flags */
226 };
227
228 /*
229  * The set of specific options for a tracer. Your tracer
230  * have to set the initial value of the flags val.
231  */
232 struct tracer_flags {
233         u32                     val;
234         struct tracer_opt       *opts;
235 };
236
237 /* Makes more easy to define a tracer opt */
238 #define TRACER_OPT(s, b)        .name = #s, .bit = b
239
240
241 /**
242  * struct tracer - a specific tracer and its callbacks to interact with debugfs
243  * @name: the name chosen to select it on the available_tracers file
244  * @init: called when one switches to this tracer (echo name > current_tracer)
245  * @reset: called when one switches to another tracer
246  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
247  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
248  * @open: called when the trace file is opened
249  * @pipe_open: called when the trace_pipe file is opened
250  * @wait_pipe: override how the user waits for traces on trace_pipe
251  * @close: called when the trace file is released
252  * @read: override the default read callback on trace_pipe
253  * @splice_read: override the default splice_read callback on trace_pipe
254  * @selftest: selftest to run on boot (see trace_selftest.c)
255  * @print_headers: override the first lines that describe your columns
256  * @print_line: callback that prints a trace
257  * @set_flag: signals one of your private flags changed (trace_options file)
258  * @flags: your private flags
259  */
260 struct tracer {
261         const char              *name;
262         int                     (*init)(struct trace_array *tr);
263         void                    (*reset)(struct trace_array *tr);
264         void                    (*start)(struct trace_array *tr);
265         void                    (*stop)(struct trace_array *tr);
266         void                    (*open)(struct trace_iterator *iter);
267         void                    (*pipe_open)(struct trace_iterator *iter);
268         void                    (*wait_pipe)(struct trace_iterator *iter);
269         void                    (*close)(struct trace_iterator *iter);
270         ssize_t                 (*read)(struct trace_iterator *iter,
271                                         struct file *filp, char __user *ubuf,
272                                         size_t cnt, loff_t *ppos);
273         ssize_t                 (*splice_read)(struct trace_iterator *iter,
274                                                struct file *filp,
275                                                loff_t *ppos,
276                                                struct pipe_inode_info *pipe,
277                                                size_t len,
278                                                unsigned int flags);
279 #ifdef CONFIG_FTRACE_STARTUP_TEST
280         int                     (*selftest)(struct tracer *trace,
281                                             struct trace_array *tr);
282 #endif
283         void                    (*print_header)(struct seq_file *m);
284         enum print_line_t       (*print_line)(struct trace_iterator *iter);
285         /* If you handled the flag setting, return 0 */
286         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
287         struct tracer           *next;
288         int                     print_max;
289         struct tracer_flags     *flags;
290 };
291
292
293 #define TRACE_PIPE_ALL_CPU      -1
294
295 int tracer_init(struct tracer *t, struct trace_array *tr);
296 int tracing_is_enabled(void);
297 void trace_wake_up(void);
298 void tracing_reset(struct trace_array *tr, int cpu);
299 void tracing_reset_online_cpus(struct trace_array *tr);
300 void tracing_reset_current(int cpu);
301 void tracing_reset_current_online_cpus(void);
302 int tracing_open_generic(struct inode *inode, struct file *filp);
303 struct dentry *trace_create_file(const char *name,
304                                  mode_t mode,
305                                  struct dentry *parent,
306                                  void *data,
307                                  const struct file_operations *fops);
308
309 struct dentry *tracing_init_dentry(void);
310 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
311
312 struct ring_buffer_event;
313
314 struct ring_buffer_event *
315 trace_buffer_lock_reserve(struct ring_buffer *buffer,
316                           int type,
317                           unsigned long len,
318                           unsigned long flags,
319                           int pc);
320 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
321                                 struct ring_buffer_event *event,
322                                 unsigned long flags, int pc);
323
324 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
325                                                 struct trace_array_cpu *data);
326
327 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
328                                           int *ent_cpu, u64 *ent_ts);
329
330 void default_wait_pipe(struct trace_iterator *iter);
331 void poll_wait_pipe(struct trace_iterator *iter);
332
333 void ftrace(struct trace_array *tr,
334                             struct trace_array_cpu *data,
335                             unsigned long ip,
336                             unsigned long parent_ip,
337                             unsigned long flags, int pc);
338 void tracing_sched_switch_trace(struct trace_array *tr,
339                                 struct task_struct *prev,
340                                 struct task_struct *next,
341                                 unsigned long flags, int pc);
342
343 void tracing_sched_wakeup_trace(struct trace_array *tr,
344                                 struct task_struct *wakee,
345                                 struct task_struct *cur,
346                                 unsigned long flags, int pc);
347 void trace_special(struct trace_array *tr,
348                    struct trace_array_cpu *data,
349                    unsigned long arg1,
350                    unsigned long arg2,
351                    unsigned long arg3, int pc);
352 void trace_function(struct trace_array *tr,
353                     unsigned long ip,
354                     unsigned long parent_ip,
355                     unsigned long flags, int pc);
356
357 void trace_graph_return(struct ftrace_graph_ret *trace);
358 int trace_graph_entry(struct ftrace_graph_ent *trace);
359 void set_graph_array(struct trace_array *tr);
360
361 void tracing_start_cmdline_record(void);
362 void tracing_stop_cmdline_record(void);
363 void tracing_sched_switch_assign_trace(struct trace_array *tr);
364 void tracing_stop_sched_switch_record(void);
365 void tracing_start_sched_switch_record(void);
366 int register_tracer(struct tracer *type);
367 void unregister_tracer(struct tracer *type);
368 int is_tracing_stopped(void);
369
370 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
371
372 #ifdef CONFIG_TRACER_MAX_TRACE
373 extern unsigned long tracing_max_latency;
374 extern unsigned long tracing_thresh;
375
376 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
377 void update_max_tr_single(struct trace_array *tr,
378                           struct task_struct *tsk, int cpu);
379 #endif /* CONFIG_TRACER_MAX_TRACE */
380
381 #ifdef CONFIG_STACKTRACE
382 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
383                         int skip, int pc);
384
385 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
386                             int pc);
387
388 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
389                    int pc);
390 #else
391 static inline void ftrace_trace_stack(struct trace_array *tr,
392                                       unsigned long flags, int skip, int pc)
393 {
394 }
395
396 static inline void ftrace_trace_userstack(struct trace_array *tr,
397                                           unsigned long flags, int pc)
398 {
399 }
400
401 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
402                                  int skip, int pc)
403 {
404 }
405 #endif /* CONFIG_STACKTRACE */
406
407 extern cycle_t ftrace_now(int cpu);
408
409 extern void trace_find_cmdline(int pid, char comm[]);
410
411 #ifdef CONFIG_DYNAMIC_FTRACE
412 extern unsigned long ftrace_update_tot_cnt;
413 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
414 extern int DYN_FTRACE_TEST_NAME(void);
415 #endif
416
417 extern int ring_buffer_expanded;
418 extern bool tracing_selftest_disabled;
419 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
420
421 #ifdef CONFIG_FTRACE_STARTUP_TEST
422 extern int trace_selftest_startup_function(struct tracer *trace,
423                                            struct trace_array *tr);
424 extern int trace_selftest_startup_function_graph(struct tracer *trace,
425                                                  struct trace_array *tr);
426 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
427                                           struct trace_array *tr);
428 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
429                                              struct trace_array *tr);
430 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
431                                                  struct trace_array *tr);
432 extern int trace_selftest_startup_wakeup(struct tracer *trace,
433                                          struct trace_array *tr);
434 extern int trace_selftest_startup_nop(struct tracer *trace,
435                                          struct trace_array *tr);
436 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
437                                                struct trace_array *tr);
438 extern int trace_selftest_startup_sysprof(struct tracer *trace,
439                                                struct trace_array *tr);
440 extern int trace_selftest_startup_branch(struct tracer *trace,
441                                          struct trace_array *tr);
442 extern int trace_selftest_startup_hw_branches(struct tracer *trace,
443                                               struct trace_array *tr);
444 #endif /* CONFIG_FTRACE_STARTUP_TEST */
445
446 extern void *head_page(struct trace_array_cpu *data);
447 extern unsigned long long ns2usecs(cycle_t nsec);
448 extern int
449 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
450 extern int
451 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
452 extern int
453 trace_array_vprintk(struct trace_array *tr,
454                     unsigned long ip, const char *fmt, va_list args);
455 int trace_array_printk(struct trace_array *tr,
456                        unsigned long ip, const char *fmt, ...);
457
458 extern unsigned long trace_flags;
459
460 extern int trace_clock_id;
461
462 /* Standard output formatting function used for function return traces */
463 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
464 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
465 extern enum print_line_t
466 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
467
468 #ifdef CONFIG_DYNAMIC_FTRACE
469 /* TODO: make this variable */
470 #define FTRACE_GRAPH_MAX_FUNCS          32
471 extern int ftrace_graph_count;
472 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
473
474 static inline int ftrace_graph_addr(unsigned long addr)
475 {
476         int i;
477
478         if (!ftrace_graph_count || test_tsk_trace_graph(current))
479                 return 1;
480
481         for (i = 0; i < ftrace_graph_count; i++) {
482                 if (addr == ftrace_graph_funcs[i])
483                         return 1;
484         }
485
486         return 0;
487 }
488 #else
489 static inline int ftrace_trace_addr(unsigned long addr)
490 {
491         return 1;
492 }
493 static inline int ftrace_graph_addr(unsigned long addr)
494 {
495         return 1;
496 }
497 #endif /* CONFIG_DYNAMIC_FTRACE */
498 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
499 static inline enum print_line_t
500 print_graph_function(struct trace_iterator *iter)
501 {
502         return TRACE_TYPE_UNHANDLED;
503 }
504 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
505
506 extern struct pid *ftrace_pid_trace;
507
508 #ifdef CONFIG_FUNCTION_TRACER
509 static inline int ftrace_trace_task(struct task_struct *task)
510 {
511         if (!ftrace_pid_trace)
512                 return 1;
513
514         return test_tsk_trace_trace(task);
515 }
516 #else
517 static inline int ftrace_trace_task(struct task_struct *task)
518 {
519         return 1;
520 }
521 #endif
522
523 /*
524  * struct trace_parser - servers for reading the user input separated by spaces
525  * @cont: set if the input is not complete - no final space char was found
526  * @buffer: holds the parsed user input
527  * @idx: user input lenght
528  * @size: buffer size
529  */
530 struct trace_parser {
531         bool            cont;
532         char            *buffer;
533         unsigned        idx;
534         unsigned        size;
535 };
536
537 static inline bool trace_parser_loaded(struct trace_parser *parser)
538 {
539         return (parser->idx != 0);
540 }
541
542 static inline bool trace_parser_cont(struct trace_parser *parser)
543 {
544         return parser->cont;
545 }
546
547 static inline void trace_parser_clear(struct trace_parser *parser)
548 {
549         parser->cont = false;
550         parser->idx = 0;
551 }
552
553 extern int trace_parser_get_init(struct trace_parser *parser, int size);
554 extern void trace_parser_put(struct trace_parser *parser);
555 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
556         size_t cnt, loff_t *ppos);
557
558 /*
559  * trace_iterator_flags is an enumeration that defines bit
560  * positions into trace_flags that controls the output.
561  *
562  * NOTE: These bits must match the trace_options array in
563  *       trace.c.
564  */
565 enum trace_iterator_flags {
566         TRACE_ITER_PRINT_PARENT         = 0x01,
567         TRACE_ITER_SYM_OFFSET           = 0x02,
568         TRACE_ITER_SYM_ADDR             = 0x04,
569         TRACE_ITER_VERBOSE              = 0x08,
570         TRACE_ITER_RAW                  = 0x10,
571         TRACE_ITER_HEX                  = 0x20,
572         TRACE_ITER_BIN                  = 0x40,
573         TRACE_ITER_BLOCK                = 0x80,
574         TRACE_ITER_STACKTRACE           = 0x100,
575         TRACE_ITER_SCHED_TREE           = 0x200,
576         TRACE_ITER_PRINTK               = 0x400,
577         TRACE_ITER_PREEMPTONLY          = 0x800,
578         TRACE_ITER_BRANCH               = 0x1000,
579         TRACE_ITER_ANNOTATE             = 0x2000,
580         TRACE_ITER_USERSTACKTRACE       = 0x4000,
581         TRACE_ITER_SYM_USEROBJ          = 0x8000,
582         TRACE_ITER_PRINTK_MSGONLY       = 0x10000,
583         TRACE_ITER_CONTEXT_INFO         = 0x20000, /* Print pid/cpu/time */
584         TRACE_ITER_LATENCY_FMT          = 0x40000,
585         TRACE_ITER_SLEEP_TIME           = 0x80000,
586         TRACE_ITER_GRAPH_TIME           = 0x100000,
587 };
588
589 /*
590  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
591  * control the output of kernel symbols.
592  */
593 #define TRACE_ITER_SYM_MASK \
594         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
595
596 extern struct tracer nop_trace;
597
598 /**
599  * ftrace_preempt_disable - disable preemption scheduler safe
600  *
601  * When tracing can happen inside the scheduler, there exists
602  * cases that the tracing might happen before the need_resched
603  * flag is checked. If this happens and the tracer calls
604  * preempt_enable (after a disable), a schedule might take place
605  * causing an infinite recursion.
606  *
607  * To prevent this, we read the need_resched flag before
608  * disabling preemption. When we want to enable preemption we
609  * check the flag, if it is set, then we call preempt_enable_no_resched.
610  * Otherwise, we call preempt_enable.
611  *
612  * The rational for doing the above is that if need_resched is set
613  * and we have yet to reschedule, we are either in an atomic location
614  * (where we do not need to check for scheduling) or we are inside
615  * the scheduler and do not want to resched.
616  */
617 static inline int ftrace_preempt_disable(void)
618 {
619         int resched;
620
621         resched = need_resched();
622         preempt_disable_notrace();
623
624         return resched;
625 }
626
627 /**
628  * ftrace_preempt_enable - enable preemption scheduler safe
629  * @resched: the return value from ftrace_preempt_disable
630  *
631  * This is a scheduler safe way to enable preemption and not miss
632  * any preemption checks. The disabled saved the state of preemption.
633  * If resched is set, then we are either inside an atomic or
634  * are inside the scheduler (we would have already scheduled
635  * otherwise). In this case, we do not want to call normal
636  * preempt_enable, but preempt_enable_no_resched instead.
637  */
638 static inline void ftrace_preempt_enable(int resched)
639 {
640         if (resched)
641                 preempt_enable_no_resched_notrace();
642         else
643                 preempt_enable_notrace();
644 }
645
646 #ifdef CONFIG_BRANCH_TRACER
647 extern int enable_branch_tracing(struct trace_array *tr);
648 extern void disable_branch_tracing(void);
649 static inline int trace_branch_enable(struct trace_array *tr)
650 {
651         if (trace_flags & TRACE_ITER_BRANCH)
652                 return enable_branch_tracing(tr);
653         return 0;
654 }
655 static inline void trace_branch_disable(void)
656 {
657         /* due to races, always disable */
658         disable_branch_tracing();
659 }
660 #else
661 static inline int trace_branch_enable(struct trace_array *tr)
662 {
663         return 0;
664 }
665 static inline void trace_branch_disable(void)
666 {
667 }
668 #endif /* CONFIG_BRANCH_TRACER */
669
670 /* set ring buffers to default size if not already done so */
671 int tracing_update_buffers(void);
672
673 /* trace event type bit fields, not numeric */
674 enum {
675         TRACE_EVENT_TYPE_PRINTF         = 1,
676         TRACE_EVENT_TYPE_RAW            = 2,
677 };
678
679 struct ftrace_event_field {
680         struct list_head        link;
681         char                    *name;
682         char                    *type;
683         int                     filter_type;
684         int                     offset;
685         int                     size;
686         int                     is_signed;
687 };
688
689 struct event_filter {
690         int                     n_preds;
691         struct filter_pred      **preds;
692         char                    *filter_string;
693         bool                    no_reset;
694 };
695
696 struct event_subsystem {
697         struct list_head        list;
698         const char              *name;
699         struct dentry           *entry;
700         struct event_filter     *filter;
701         int                     nr_events;
702 };
703
704 struct filter_pred;
705 struct regex;
706
707 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
708                                  int val1, int val2);
709
710 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
711
712 enum regex_type {
713         MATCH_FULL,
714         MATCH_FRONT_ONLY,
715         MATCH_MIDDLE_ONLY,
716         MATCH_END_ONLY,
717 };
718
719 struct regex {
720         char                    pattern[MAX_FILTER_STR_VAL];
721         int                     len;
722         int                     field_len;
723         regex_match_func        match;
724 };
725
726 struct filter_pred {
727         filter_pred_fn_t        fn;
728         u64                     val;
729         struct regex            regex;
730         char                    *field_name;
731         int                     offset;
732         int                     not;
733         int                     op;
734         int                     pop_n;
735 };
736
737 extern enum regex_type
738 filter_parse_regex(char *buff, int len, char **search, int *not);
739 extern void print_event_filter(struct ftrace_event_call *call,
740                                struct trace_seq *s);
741 extern int apply_event_filter(struct ftrace_event_call *call,
742                               char *filter_string);
743 extern int apply_subsystem_event_filter(struct event_subsystem *system,
744                                         char *filter_string);
745 extern void print_subsystem_event_filter(struct event_subsystem *system,
746                                          struct trace_seq *s);
747 extern int filter_assign_type(const char *type);
748
749 static inline int
750 filter_check_discard(struct ftrace_event_call *call, void *rec,
751                      struct ring_buffer *buffer,
752                      struct ring_buffer_event *event)
753 {
754         if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) {
755                 ring_buffer_discard_commit(buffer, event);
756                 return 1;
757         }
758
759         return 0;
760 }
761
762 extern struct mutex event_mutex;
763 extern struct list_head ftrace_events;
764
765 extern const char *__start___trace_bprintk_fmt[];
766 extern const char *__stop___trace_bprintk_fmt[];
767
768 #undef FTRACE_ENTRY
769 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
770         extern struct ftrace_event_call event_##call;
771 #undef FTRACE_ENTRY_DUP
772 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
773         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
774 #include "trace_entries.h"
775
776 #endif /* _LINUX_KERNEL_TRACE_H */