tracing: Add individual syscalls tracepoint id support
[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 /*
46  * Function trace entry - function address and parent function addres:
47  */
48 struct ftrace_entry {
49         struct trace_entry      ent;
50         unsigned long           ip;
51         unsigned long           parent_ip;
52 };
53
54 /* Function call entry */
55 struct ftrace_graph_ent_entry {
56         struct trace_entry              ent;
57         struct ftrace_graph_ent         graph_ent;
58 };
59
60 /* Function return entry */
61 struct ftrace_graph_ret_entry {
62         struct trace_entry              ent;
63         struct ftrace_graph_ret         ret;
64 };
65 extern struct tracer boot_tracer;
66
67 /*
68  * Context switch trace entry - which task (and prio) we switched from/to:
69  */
70 struct ctx_switch_entry {
71         struct trace_entry      ent;
72         unsigned int            prev_pid;
73         unsigned char           prev_prio;
74         unsigned char           prev_state;
75         unsigned int            next_pid;
76         unsigned char           next_prio;
77         unsigned char           next_state;
78         unsigned int            next_cpu;
79 };
80
81 /*
82  * Special (free-form) trace entry:
83  */
84 struct special_entry {
85         struct trace_entry      ent;
86         unsigned long           arg1;
87         unsigned long           arg2;
88         unsigned long           arg3;
89 };
90
91 /*
92  * Stack-trace entry:
93  */
94
95 #define FTRACE_STACK_ENTRIES    8
96
97 struct stack_entry {
98         struct trace_entry      ent;
99         unsigned long           caller[FTRACE_STACK_ENTRIES];
100 };
101
102 struct userstack_entry {
103         struct trace_entry      ent;
104         unsigned long           caller[FTRACE_STACK_ENTRIES];
105 };
106
107 /*
108  * trace_printk entry:
109  */
110 struct bprint_entry {
111         struct trace_entry      ent;
112         unsigned long           ip;
113         const char              *fmt;
114         u32                     buf[];
115 };
116
117 struct print_entry {
118         struct trace_entry      ent;
119         unsigned long           ip;
120         char                    buf[];
121 };
122
123 #define TRACE_OLD_SIZE          88
124
125 struct trace_field_cont {
126         unsigned char           type;
127         /* Temporary till we get rid of this completely */
128         char                    buf[TRACE_OLD_SIZE - 1];
129 };
130
131 struct trace_mmiotrace_rw {
132         struct trace_entry      ent;
133         struct mmiotrace_rw     rw;
134 };
135
136 struct trace_mmiotrace_map {
137         struct trace_entry      ent;
138         struct mmiotrace_map    map;
139 };
140
141 struct trace_boot_call {
142         struct trace_entry      ent;
143         struct boot_trace_call boot_call;
144 };
145
146 struct trace_boot_ret {
147         struct trace_entry      ent;
148         struct boot_trace_ret boot_ret;
149 };
150
151 #define TRACE_FUNC_SIZE 30
152 #define TRACE_FILE_SIZE 20
153 struct trace_branch {
154         struct trace_entry      ent;
155         unsigned                line;
156         char                    func[TRACE_FUNC_SIZE+1];
157         char                    file[TRACE_FILE_SIZE+1];
158         char                    correct;
159 };
160
161 struct hw_branch_entry {
162         struct trace_entry      ent;
163         u64                     from;
164         u64                     to;
165 };
166
167 struct trace_power {
168         struct trace_entry      ent;
169         struct power_trace      state_data;
170 };
171
172 enum kmemtrace_type_id {
173         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
174         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
175         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
176 };
177
178 struct kmemtrace_alloc_entry {
179         struct trace_entry      ent;
180         enum kmemtrace_type_id type_id;
181         unsigned long call_site;
182         const void *ptr;
183         size_t bytes_req;
184         size_t bytes_alloc;
185         gfp_t gfp_flags;
186         int node;
187 };
188
189 struct kmemtrace_free_entry {
190         struct trace_entry      ent;
191         enum kmemtrace_type_id type_id;
192         unsigned long call_site;
193         const void *ptr;
194 };
195
196 struct syscall_trace_enter {
197         struct trace_entry      ent;
198         int                     nr;
199         unsigned long           args[];
200 };
201
202 struct syscall_trace_exit {
203         struct trace_entry      ent;
204         int                     nr;
205         unsigned long           ret;
206 };
207
208
209 /*
210  * trace_flag_type is an enumeration that holds different
211  * states when a trace occurs. These are:
212  *  IRQS_OFF            - interrupts were disabled
213  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
214  *  NEED_RESCED         - reschedule is requested
215  *  HARDIRQ             - inside an interrupt handler
216  *  SOFTIRQ             - inside a softirq handler
217  */
218 enum trace_flag_type {
219         TRACE_FLAG_IRQS_OFF             = 0x01,
220         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
221         TRACE_FLAG_NEED_RESCHED         = 0x04,
222         TRACE_FLAG_HARDIRQ              = 0x08,
223         TRACE_FLAG_SOFTIRQ              = 0x10,
224 };
225
226 #define TRACE_BUF_SIZE          1024
227
228 /*
229  * The CPU trace array - it consists of thousands of trace entries
230  * plus some other descriptor data: (for example which task started
231  * the trace, etc.)
232  */
233 struct trace_array_cpu {
234         atomic_t                disabled;
235         void                    *buffer_page;   /* ring buffer spare */
236
237         /* these fields get copied into max-trace: */
238         unsigned long           trace_idx;
239         unsigned long           overrun;
240         unsigned long           saved_latency;
241         unsigned long           critical_start;
242         unsigned long           critical_end;
243         unsigned long           critical_sequence;
244         unsigned long           nice;
245         unsigned long           policy;
246         unsigned long           rt_priority;
247         cycle_t                 preempt_timestamp;
248         pid_t                   pid;
249         uid_t                   uid;
250         char                    comm[TASK_COMM_LEN];
251 };
252
253 /*
254  * The trace array - an array of per-CPU trace arrays. This is the
255  * highest level data structure that individual tracers deal with.
256  * They have on/off state as well:
257  */
258 struct trace_array {
259         struct ring_buffer      *buffer;
260         unsigned long           entries;
261         int                     cpu;
262         cycle_t                 time_start;
263         struct task_struct      *waiter;
264         struct trace_array_cpu  *data[NR_CPUS];
265 };
266
267 #define FTRACE_CMP_TYPE(var, type) \
268         __builtin_types_compatible_p(typeof(var), type *)
269
270 #undef IF_ASSIGN
271 #define IF_ASSIGN(var, entry, etype, id)                \
272         if (FTRACE_CMP_TYPE(var, etype)) {              \
273                 var = (typeof(var))(entry);             \
274                 WARN_ON(id && (entry)->type != id);     \
275                 break;                                  \
276         }
277
278 /* Will cause compile errors if type is not found. */
279 extern void __ftrace_bad_type(void);
280
281 /*
282  * The trace_assign_type is a verifier that the entry type is
283  * the same as the type being assigned. To add new types simply
284  * add a line with the following format:
285  *
286  * IF_ASSIGN(var, ent, type, id);
287  *
288  *  Where "type" is the trace type that includes the trace_entry
289  *  as the "ent" item. And "id" is the trace identifier that is
290  *  used in the trace_type enum.
291  *
292  *  If the type can have more than one id, then use zero.
293  */
294 #define trace_assign_type(var, ent)                                     \
295         do {                                                            \
296                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
297                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
298                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
299                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
300                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
301                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
302                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
303                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
304                           TRACE_MMIO_RW);                               \
305                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
306                           TRACE_MMIO_MAP);                              \
307                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
308                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
309                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
310                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
311                           TRACE_GRAPH_ENT);             \
312                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
313                           TRACE_GRAPH_RET);             \
314                 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
315                 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
316                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
317                           TRACE_KMEM_ALLOC);    \
318                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
319                           TRACE_KMEM_FREE);     \
320                 __ftrace_bad_type();                                    \
321         } while (0)
322
323 /*
324  * An option specific to a tracer. This is a boolean value.
325  * The bit is the bit index that sets its value on the
326  * flags value in struct tracer_flags.
327  */
328 struct tracer_opt {
329         const char      *name; /* Will appear on the trace_options file */
330         u32             bit; /* Mask assigned in val field in tracer_flags */
331 };
332
333 /*
334  * The set of specific options for a tracer. Your tracer
335  * have to set the initial value of the flags val.
336  */
337 struct tracer_flags {
338         u32                     val;
339         struct tracer_opt       *opts;
340 };
341
342 /* Makes more easy to define a tracer opt */
343 #define TRACER_OPT(s, b)        .name = #s, .bit = b
344
345
346 /**
347  * struct tracer - a specific tracer and its callbacks to interact with debugfs
348  * @name: the name chosen to select it on the available_tracers file
349  * @init: called when one switches to this tracer (echo name > current_tracer)
350  * @reset: called when one switches to another tracer
351  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
352  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
353  * @open: called when the trace file is opened
354  * @pipe_open: called when the trace_pipe file is opened
355  * @wait_pipe: override how the user waits for traces on trace_pipe
356  * @close: called when the trace file is released
357  * @read: override the default read callback on trace_pipe
358  * @splice_read: override the default splice_read callback on trace_pipe
359  * @selftest: selftest to run on boot (see trace_selftest.c)
360  * @print_headers: override the first lines that describe your columns
361  * @print_line: callback that prints a trace
362  * @set_flag: signals one of your private flags changed (trace_options file)
363  * @flags: your private flags
364  */
365 struct tracer {
366         const char              *name;
367         int                     (*init)(struct trace_array *tr);
368         void                    (*reset)(struct trace_array *tr);
369         void                    (*start)(struct trace_array *tr);
370         void                    (*stop)(struct trace_array *tr);
371         void                    (*open)(struct trace_iterator *iter);
372         void                    (*pipe_open)(struct trace_iterator *iter);
373         void                    (*wait_pipe)(struct trace_iterator *iter);
374         void                    (*close)(struct trace_iterator *iter);
375         ssize_t                 (*read)(struct trace_iterator *iter,
376                                         struct file *filp, char __user *ubuf,
377                                         size_t cnt, loff_t *ppos);
378         ssize_t                 (*splice_read)(struct trace_iterator *iter,
379                                                struct file *filp,
380                                                loff_t *ppos,
381                                                struct pipe_inode_info *pipe,
382                                                size_t len,
383                                                unsigned int flags);
384 #ifdef CONFIG_FTRACE_STARTUP_TEST
385         int                     (*selftest)(struct tracer *trace,
386                                             struct trace_array *tr);
387 #endif
388         void                    (*print_header)(struct seq_file *m);
389         enum print_line_t       (*print_line)(struct trace_iterator *iter);
390         /* If you handled the flag setting, return 0 */
391         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
392         struct tracer           *next;
393         int                     print_max;
394         struct tracer_flags     *flags;
395         struct tracer_stat      *stats;
396 };
397
398
399 #define TRACE_PIPE_ALL_CPU      -1
400
401 int tracer_init(struct tracer *t, struct trace_array *tr);
402 int tracing_is_enabled(void);
403 void trace_wake_up(void);
404 void tracing_reset(struct trace_array *tr, int cpu);
405 void tracing_reset_online_cpus(struct trace_array *tr);
406 void tracing_reset_current(int cpu);
407 void tracing_reset_current_online_cpus(void);
408 int tracing_open_generic(struct inode *inode, struct file *filp);
409 struct dentry *trace_create_file(const char *name,
410                                  mode_t mode,
411                                  struct dentry *parent,
412                                  void *data,
413                                  const struct file_operations *fops);
414
415 struct dentry *tracing_init_dentry(void);
416 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
417
418 struct ring_buffer_event;
419
420 struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
421                                                     int type,
422                                                     unsigned long len,
423                                                     unsigned long flags,
424                                                     int pc);
425 void trace_buffer_unlock_commit(struct trace_array *tr,
426                                 struct ring_buffer_event *event,
427                                 unsigned long flags, int pc);
428
429 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
430                                                 struct trace_array_cpu *data);
431
432 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
433                                           int *ent_cpu, u64 *ent_ts);
434
435 void default_wait_pipe(struct trace_iterator *iter);
436 void poll_wait_pipe(struct trace_iterator *iter);
437
438 void ftrace(struct trace_array *tr,
439                             struct trace_array_cpu *data,
440                             unsigned long ip,
441                             unsigned long parent_ip,
442                             unsigned long flags, int pc);
443 void tracing_sched_switch_trace(struct trace_array *tr,
444                                 struct task_struct *prev,
445                                 struct task_struct *next,
446                                 unsigned long flags, int pc);
447
448 void tracing_sched_wakeup_trace(struct trace_array *tr,
449                                 struct task_struct *wakee,
450                                 struct task_struct *cur,
451                                 unsigned long flags, int pc);
452 void trace_special(struct trace_array *tr,
453                    struct trace_array_cpu *data,
454                    unsigned long arg1,
455                    unsigned long arg2,
456                    unsigned long arg3, int pc);
457 void trace_function(struct trace_array *tr,
458                     unsigned long ip,
459                     unsigned long parent_ip,
460                     unsigned long flags, int pc);
461
462 void trace_graph_return(struct ftrace_graph_ret *trace);
463 int trace_graph_entry(struct ftrace_graph_ent *trace);
464 void set_graph_array(struct trace_array *tr);
465
466 void tracing_start_cmdline_record(void);
467 void tracing_stop_cmdline_record(void);
468 void tracing_sched_switch_assign_trace(struct trace_array *tr);
469 void tracing_stop_sched_switch_record(void);
470 void tracing_start_sched_switch_record(void);
471 int register_tracer(struct tracer *type);
472 void unregister_tracer(struct tracer *type);
473
474 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
475
476 extern unsigned long tracing_max_latency;
477 extern unsigned long tracing_thresh;
478
479 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
480 void update_max_tr_single(struct trace_array *tr,
481                           struct task_struct *tsk, int cpu);
482
483 #ifdef CONFIG_STACKTRACE
484 void ftrace_trace_stack(struct trace_array *tr, unsigned long flags,
485                         int skip, int pc);
486
487 void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags,
488                             int pc);
489
490 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
491                    int pc);
492 #else
493 static inline void ftrace_trace_stack(struct trace_array *tr,
494                                       unsigned long flags, int skip, int pc)
495 {
496 }
497
498 static inline void ftrace_trace_userstack(struct trace_array *tr,
499                                           unsigned long flags, int pc)
500 {
501 }
502
503 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
504                                  int skip, int pc)
505 {
506 }
507 #endif /* CONFIG_STACKTRACE */
508
509 extern cycle_t ftrace_now(int cpu);
510
511 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
512 typedef void
513 (*tracer_switch_func_t)(void *private,
514                         void *__rq,
515                         struct task_struct *prev,
516                         struct task_struct *next);
517
518 struct tracer_switch_ops {
519         tracer_switch_func_t            func;
520         void                            *private;
521         struct tracer_switch_ops        *next;
522 };
523 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
524
525 extern void trace_find_cmdline(int pid, char comm[]);
526
527 #ifdef CONFIG_DYNAMIC_FTRACE
528 extern unsigned long ftrace_update_tot_cnt;
529 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
530 extern int DYN_FTRACE_TEST_NAME(void);
531 #endif
532
533 extern int ring_buffer_expanded;
534 extern bool tracing_selftest_disabled;
535 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
536
537 #ifdef CONFIG_FTRACE_STARTUP_TEST
538 extern int trace_selftest_startup_function(struct tracer *trace,
539                                            struct trace_array *tr);
540 extern int trace_selftest_startup_function_graph(struct tracer *trace,
541                                                  struct trace_array *tr);
542 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
543                                           struct trace_array *tr);
544 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
545                                              struct trace_array *tr);
546 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
547                                                  struct trace_array *tr);
548 extern int trace_selftest_startup_wakeup(struct tracer *trace,
549                                          struct trace_array *tr);
550 extern int trace_selftest_startup_nop(struct tracer *trace,
551                                          struct trace_array *tr);
552 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
553                                                struct trace_array *tr);
554 extern int trace_selftest_startup_sysprof(struct tracer *trace,
555                                                struct trace_array *tr);
556 extern int trace_selftest_startup_branch(struct tracer *trace,
557                                          struct trace_array *tr);
558 extern int trace_selftest_startup_hw_branches(struct tracer *trace,
559                                               struct trace_array *tr);
560 #endif /* CONFIG_FTRACE_STARTUP_TEST */
561
562 extern void *head_page(struct trace_array_cpu *data);
563 extern unsigned long long ns2usecs(cycle_t nsec);
564 extern int
565 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
566 extern int
567 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
568
569 extern unsigned long trace_flags;
570
571 /* Standard output formatting function used for function return traces */
572 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
573 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
574 extern enum print_line_t
575 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
576
577 #ifdef CONFIG_DYNAMIC_FTRACE
578 /* TODO: make this variable */
579 #define FTRACE_GRAPH_MAX_FUNCS          32
580 extern int ftrace_graph_count;
581 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
582
583 static inline int ftrace_graph_addr(unsigned long addr)
584 {
585         int i;
586
587         if (!ftrace_graph_count || test_tsk_trace_graph(current))
588                 return 1;
589
590         for (i = 0; i < ftrace_graph_count; i++) {
591                 if (addr == ftrace_graph_funcs[i])
592                         return 1;
593         }
594
595         return 0;
596 }
597 #else
598 static inline int ftrace_trace_addr(unsigned long addr)
599 {
600         return 1;
601 }
602 static inline int ftrace_graph_addr(unsigned long addr)
603 {
604         return 1;
605 }
606 #endif /* CONFIG_DYNAMIC_FTRACE */
607 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
608 static inline enum print_line_t
609 print_graph_function(struct trace_iterator *iter)
610 {
611         return TRACE_TYPE_UNHANDLED;
612 }
613 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
614
615 extern struct pid *ftrace_pid_trace;
616
617 #ifdef CONFIG_FUNCTION_TRACER
618 static inline int ftrace_trace_task(struct task_struct *task)
619 {
620         if (!ftrace_pid_trace)
621                 return 1;
622
623         return test_tsk_trace_trace(task);
624 }
625 #else
626 static inline int ftrace_trace_task(struct task_struct *task)
627 {
628         return 1;
629 }
630 #endif
631
632 /*
633  * trace_iterator_flags is an enumeration that defines bit
634  * positions into trace_flags that controls the output.
635  *
636  * NOTE: These bits must match the trace_options array in
637  *       trace.c.
638  */
639 enum trace_iterator_flags {
640         TRACE_ITER_PRINT_PARENT         = 0x01,
641         TRACE_ITER_SYM_OFFSET           = 0x02,
642         TRACE_ITER_SYM_ADDR             = 0x04,
643         TRACE_ITER_VERBOSE              = 0x08,
644         TRACE_ITER_RAW                  = 0x10,
645         TRACE_ITER_HEX                  = 0x20,
646         TRACE_ITER_BIN                  = 0x40,
647         TRACE_ITER_BLOCK                = 0x80,
648         TRACE_ITER_STACKTRACE           = 0x100,
649         TRACE_ITER_SCHED_TREE           = 0x200,
650         TRACE_ITER_PRINTK               = 0x400,
651         TRACE_ITER_PREEMPTONLY          = 0x800,
652         TRACE_ITER_BRANCH               = 0x1000,
653         TRACE_ITER_ANNOTATE             = 0x2000,
654         TRACE_ITER_USERSTACKTRACE       = 0x4000,
655         TRACE_ITER_SYM_USEROBJ          = 0x8000,
656         TRACE_ITER_PRINTK_MSGONLY       = 0x10000,
657         TRACE_ITER_CONTEXT_INFO         = 0x20000, /* Print pid/cpu/time */
658         TRACE_ITER_LATENCY_FMT          = 0x40000,
659         TRACE_ITER_GLOBAL_CLK           = 0x80000,
660         TRACE_ITER_SLEEP_TIME           = 0x100000,
661         TRACE_ITER_GRAPH_TIME           = 0x200000,
662 };
663
664 /*
665  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
666  * control the output of kernel symbols.
667  */
668 #define TRACE_ITER_SYM_MASK \
669         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
670
671 extern struct tracer nop_trace;
672
673 /**
674  * ftrace_preempt_disable - disable preemption scheduler safe
675  *
676  * When tracing can happen inside the scheduler, there exists
677  * cases that the tracing might happen before the need_resched
678  * flag is checked. If this happens and the tracer calls
679  * preempt_enable (after a disable), a schedule might take place
680  * causing an infinite recursion.
681  *
682  * To prevent this, we read the need_resched flag before
683  * disabling preemption. When we want to enable preemption we
684  * check the flag, if it is set, then we call preempt_enable_no_resched.
685  * Otherwise, we call preempt_enable.
686  *
687  * The rational for doing the above is that if need_resched is set
688  * and we have yet to reschedule, we are either in an atomic location
689  * (where we do not need to check for scheduling) or we are inside
690  * the scheduler and do not want to resched.
691  */
692 static inline int ftrace_preempt_disable(void)
693 {
694         int resched;
695
696         resched = need_resched();
697         preempt_disable_notrace();
698
699         return resched;
700 }
701
702 /**
703  * ftrace_preempt_enable - enable preemption scheduler safe
704  * @resched: the return value from ftrace_preempt_disable
705  *
706  * This is a scheduler safe way to enable preemption and not miss
707  * any preemption checks. The disabled saved the state of preemption.
708  * If resched is set, then we are either inside an atomic or
709  * are inside the scheduler (we would have already scheduled
710  * otherwise). In this case, we do not want to call normal
711  * preempt_enable, but preempt_enable_no_resched instead.
712  */
713 static inline void ftrace_preempt_enable(int resched)
714 {
715         if (resched)
716                 preempt_enable_no_resched_notrace();
717         else
718                 preempt_enable_notrace();
719 }
720
721 #ifdef CONFIG_BRANCH_TRACER
722 extern int enable_branch_tracing(struct trace_array *tr);
723 extern void disable_branch_tracing(void);
724 static inline int trace_branch_enable(struct trace_array *tr)
725 {
726         if (trace_flags & TRACE_ITER_BRANCH)
727                 return enable_branch_tracing(tr);
728         return 0;
729 }
730 static inline void trace_branch_disable(void)
731 {
732         /* due to races, always disable */
733         disable_branch_tracing();
734 }
735 #else
736 static inline int trace_branch_enable(struct trace_array *tr)
737 {
738         return 0;
739 }
740 static inline void trace_branch_disable(void)
741 {
742 }
743 #endif /* CONFIG_BRANCH_TRACER */
744
745 /* set ring buffers to default size if not already done so */
746 int tracing_update_buffers(void);
747
748 /* trace event type bit fields, not numeric */
749 enum {
750         TRACE_EVENT_TYPE_PRINTF         = 1,
751         TRACE_EVENT_TYPE_RAW            = 2,
752 };
753
754 struct ftrace_event_field {
755         struct list_head        link;
756         char                    *name;
757         char                    *type;
758         int                     offset;
759         int                     size;
760         int                     is_signed;
761 };
762
763 struct event_filter {
764         int                     n_preds;
765         struct filter_pred      **preds;
766         char                    *filter_string;
767         bool                    no_reset;
768 };
769
770 struct event_subsystem {
771         struct list_head        list;
772         const char              *name;
773         struct dentry           *entry;
774         struct event_filter     *filter;
775         int                     nr_events;
776 };
777
778 struct filter_pred;
779
780 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
781                                  int val1, int val2);
782
783 struct filter_pred {
784         filter_pred_fn_t fn;
785         u64 val;
786         char str_val[MAX_FILTER_STR_VAL];
787         int str_len;
788         char *field_name;
789         int offset;
790         int not;
791         int op;
792         int pop_n;
793 };
794
795 extern void print_event_filter(struct ftrace_event_call *call,
796                                struct trace_seq *s);
797 extern int apply_event_filter(struct ftrace_event_call *call,
798                               char *filter_string);
799 extern int apply_subsystem_event_filter(struct event_subsystem *system,
800                                         char *filter_string);
801 extern void print_subsystem_event_filter(struct event_subsystem *system,
802                                          struct trace_seq *s);
803
804 static inline int
805 filter_check_discard(struct ftrace_event_call *call, void *rec,
806                      struct ring_buffer *buffer,
807                      struct ring_buffer_event *event)
808 {
809         if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) {
810                 ring_buffer_discard_commit(buffer, event);
811                 return 1;
812         }
813
814         return 0;
815 }
816
817 #define DEFINE_COMPARISON_PRED(type)                                    \
818 static int filter_pred_##type(struct filter_pred *pred, void *event,    \
819                               int val1, int val2)                       \
820 {                                                                       \
821         type *addr = (type *)(event + pred->offset);                    \
822         type val = (type)pred->val;                                     \
823         int match = 0;                                                  \
824                                                                         \
825         switch (pred->op) {                                             \
826         case OP_LT:                                                     \
827                 match = (*addr < val);                                  \
828                 break;                                                  \
829         case OP_LE:                                                     \
830                 match = (*addr <= val);                                 \
831                 break;                                                  \
832         case OP_GT:                                                     \
833                 match = (*addr > val);                                  \
834                 break;                                                  \
835         case OP_GE:                                                     \
836                 match = (*addr >= val);                                 \
837                 break;                                                  \
838         default:                                                        \
839                 break;                                                  \
840         }                                                               \
841                                                                         \
842         return match;                                                   \
843 }
844
845 #define DEFINE_EQUALITY_PRED(size)                                      \
846 static int filter_pred_##size(struct filter_pred *pred, void *event,    \
847                               int val1, int val2)                       \
848 {                                                                       \
849         u##size *addr = (u##size *)(event + pred->offset);              \
850         u##size val = (u##size)pred->val;                               \
851         int match;                                                      \
852                                                                         \
853         match = (val == *addr) ^ pred->not;                             \
854                                                                         \
855         return match;                                                   \
856 }
857
858 extern struct mutex event_mutex;
859 extern struct list_head ftrace_events;
860
861 extern const char *__start___trace_bprintk_fmt[];
862 extern const char *__stop___trace_bprintk_fmt[];
863
864 #undef TRACE_EVENT_FORMAT
865 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
866         extern struct ftrace_event_call event_##call;
867 #undef TRACE_EVENT_FORMAT_NOFILTER
868 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
869 #include "trace_event_types.h"
870
871 #endif /* _LINUX_KERNEL_TRACE_H */