tracing: Add kprobe-based event tracer
[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         TRACE_KPROBE,
42         TRACE_KRETPROBE,
43
44         __TRACE_LAST_TYPE,
45 };
46
47 /*
48  * Function trace entry - function address and parent function addres:
49  */
50 struct ftrace_entry {
51         struct trace_entry      ent;
52         unsigned long           ip;
53         unsigned long           parent_ip;
54 };
55
56 /* Function call entry */
57 struct ftrace_graph_ent_entry {
58         struct trace_entry              ent;
59         struct ftrace_graph_ent         graph_ent;
60 };
61
62 /* Function return entry */
63 struct ftrace_graph_ret_entry {
64         struct trace_entry              ent;
65         struct ftrace_graph_ret         ret;
66 };
67 extern struct tracer boot_tracer;
68
69 /*
70  * Context switch trace entry - which task (and prio) we switched from/to:
71  */
72 struct ctx_switch_entry {
73         struct trace_entry      ent;
74         unsigned int            prev_pid;
75         unsigned char           prev_prio;
76         unsigned char           prev_state;
77         unsigned int            next_pid;
78         unsigned char           next_prio;
79         unsigned char           next_state;
80         unsigned int            next_cpu;
81 };
82
83 /*
84  * Special (free-form) trace entry:
85  */
86 struct special_entry {
87         struct trace_entry      ent;
88         unsigned long           arg1;
89         unsigned long           arg2;
90         unsigned long           arg3;
91 };
92
93 /*
94  * Stack-trace entry:
95  */
96
97 #define FTRACE_STACK_ENTRIES    8
98
99 struct stack_entry {
100         struct trace_entry      ent;
101         unsigned long           caller[FTRACE_STACK_ENTRIES];
102 };
103
104 struct userstack_entry {
105         struct trace_entry      ent;
106         unsigned long           caller[FTRACE_STACK_ENTRIES];
107 };
108
109 /*
110  * trace_printk entry:
111  */
112 struct bprint_entry {
113         struct trace_entry      ent;
114         unsigned long           ip;
115         const char              *fmt;
116         u32                     buf[];
117 };
118
119 struct print_entry {
120         struct trace_entry      ent;
121         unsigned long           ip;
122         char                    buf[];
123 };
124
125 #define TRACE_OLD_SIZE          88
126
127 struct trace_field_cont {
128         unsigned char           type;
129         /* Temporary till we get rid of this completely */
130         char                    buf[TRACE_OLD_SIZE - 1];
131 };
132
133 struct trace_mmiotrace_rw {
134         struct trace_entry      ent;
135         struct mmiotrace_rw     rw;
136 };
137
138 struct trace_mmiotrace_map {
139         struct trace_entry      ent;
140         struct mmiotrace_map    map;
141 };
142
143 struct trace_boot_call {
144         struct trace_entry      ent;
145         struct boot_trace_call boot_call;
146 };
147
148 struct trace_boot_ret {
149         struct trace_entry      ent;
150         struct boot_trace_ret boot_ret;
151 };
152
153 #define TRACE_FUNC_SIZE 30
154 #define TRACE_FILE_SIZE 20
155 struct trace_branch {
156         struct trace_entry      ent;
157         unsigned                line;
158         char                    func[TRACE_FUNC_SIZE+1];
159         char                    file[TRACE_FILE_SIZE+1];
160         char                    correct;
161 };
162
163 struct hw_branch_entry {
164         struct trace_entry      ent;
165         u64                     from;
166         u64                     to;
167 };
168
169 struct trace_power {
170         struct trace_entry      ent;
171         struct power_trace      state_data;
172 };
173
174 enum kmemtrace_type_id {
175         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
176         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
177         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
178 };
179
180 struct kmemtrace_alloc_entry {
181         struct trace_entry      ent;
182         enum kmemtrace_type_id type_id;
183         unsigned long call_site;
184         const void *ptr;
185         size_t bytes_req;
186         size_t bytes_alloc;
187         gfp_t gfp_flags;
188         int node;
189 };
190
191 struct kmemtrace_free_entry {
192         struct trace_entry      ent;
193         enum kmemtrace_type_id type_id;
194         unsigned long call_site;
195         const void *ptr;
196 };
197
198 struct syscall_trace_enter {
199         struct trace_entry      ent;
200         int                     nr;
201         unsigned long           args[];
202 };
203
204 struct syscall_trace_exit {
205         struct trace_entry      ent;
206         int                     nr;
207         unsigned long           ret;
208 };
209
210 struct kprobe_trace_entry {
211         struct trace_entry      ent;
212         unsigned long           ip;
213         int                     nargs;
214         unsigned long           args[];
215 };
216
217 #define SIZEOF_KPROBE_TRACE_ENTRY(n)                    \
218         (offsetof(struct kprobe_trace_entry, args) +    \
219         (sizeof(unsigned long) * (n)))
220
221 struct kretprobe_trace_entry {
222         struct trace_entry      ent;
223         unsigned long           func;
224         unsigned long           ret_ip;
225         int                     nargs;
226         unsigned long           args[];
227 };
228
229 #define SIZEOF_KRETPROBE_TRACE_ENTRY(n)                 \
230         (offsetof(struct kretprobe_trace_entry, args) + \
231         (sizeof(unsigned long) * (n)))
232
233
234
235 /*
236  * trace_flag_type is an enumeration that holds different
237  * states when a trace occurs. These are:
238  *  IRQS_OFF            - interrupts were disabled
239  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
240  *  NEED_RESCED         - reschedule is requested
241  *  HARDIRQ             - inside an interrupt handler
242  *  SOFTIRQ             - inside a softirq handler
243  */
244 enum trace_flag_type {
245         TRACE_FLAG_IRQS_OFF             = 0x01,
246         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
247         TRACE_FLAG_NEED_RESCHED         = 0x04,
248         TRACE_FLAG_HARDIRQ              = 0x08,
249         TRACE_FLAG_SOFTIRQ              = 0x10,
250 };
251
252 #define TRACE_BUF_SIZE          1024
253
254 /*
255  * The CPU trace array - it consists of thousands of trace entries
256  * plus some other descriptor data: (for example which task started
257  * the trace, etc.)
258  */
259 struct trace_array_cpu {
260         atomic_t                disabled;
261         void                    *buffer_page;   /* ring buffer spare */
262
263         /* these fields get copied into max-trace: */
264         unsigned long           trace_idx;
265         unsigned long           overrun;
266         unsigned long           saved_latency;
267         unsigned long           critical_start;
268         unsigned long           critical_end;
269         unsigned long           critical_sequence;
270         unsigned long           nice;
271         unsigned long           policy;
272         unsigned long           rt_priority;
273         cycle_t                 preempt_timestamp;
274         pid_t                   pid;
275         uid_t                   uid;
276         char                    comm[TASK_COMM_LEN];
277 };
278
279 /*
280  * The trace array - an array of per-CPU trace arrays. This is the
281  * highest level data structure that individual tracers deal with.
282  * They have on/off state as well:
283  */
284 struct trace_array {
285         struct ring_buffer      *buffer;
286         unsigned long           entries;
287         int                     cpu;
288         cycle_t                 time_start;
289         struct task_struct      *waiter;
290         struct trace_array_cpu  *data[NR_CPUS];
291 };
292
293 #define FTRACE_CMP_TYPE(var, type) \
294         __builtin_types_compatible_p(typeof(var), type *)
295
296 #undef IF_ASSIGN
297 #define IF_ASSIGN(var, entry, etype, id)                \
298         if (FTRACE_CMP_TYPE(var, etype)) {              \
299                 var = (typeof(var))(entry);             \
300                 WARN_ON(id && (entry)->type != id);     \
301                 break;                                  \
302         }
303
304 /* Will cause compile errors if type is not found. */
305 extern void __ftrace_bad_type(void);
306
307 /*
308  * The trace_assign_type is a verifier that the entry type is
309  * the same as the type being assigned. To add new types simply
310  * add a line with the following format:
311  *
312  * IF_ASSIGN(var, ent, type, id);
313  *
314  *  Where "type" is the trace type that includes the trace_entry
315  *  as the "ent" item. And "id" is the trace identifier that is
316  *  used in the trace_type enum.
317  *
318  *  If the type can have more than one id, then use zero.
319  */
320 #define trace_assign_type(var, ent)                                     \
321         do {                                                            \
322                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
323                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
324                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
325                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
326                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
327                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
328                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
329                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
330                           TRACE_MMIO_RW);                               \
331                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
332                           TRACE_MMIO_MAP);                              \
333                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
334                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
335                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
336                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
337                           TRACE_GRAPH_ENT);             \
338                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
339                           TRACE_GRAPH_RET);             \
340                 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
341                 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
342                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
343                           TRACE_KMEM_ALLOC);    \
344                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
345                           TRACE_KMEM_FREE);     \
346                 IF_ASSIGN(var, ent, struct kprobe_trace_entry,          \
347                           TRACE_KPROBE);                                \
348                 IF_ASSIGN(var, ent, struct kretprobe_trace_entry,       \
349                           TRACE_KRETPROBE);                             \
350                 __ftrace_bad_type();                                    \
351         } while (0)
352
353 /*
354  * An option specific to a tracer. This is a boolean value.
355  * The bit is the bit index that sets its value on the
356  * flags value in struct tracer_flags.
357  */
358 struct tracer_opt {
359         const char      *name; /* Will appear on the trace_options file */
360         u32             bit; /* Mask assigned in val field in tracer_flags */
361 };
362
363 /*
364  * The set of specific options for a tracer. Your tracer
365  * have to set the initial value of the flags val.
366  */
367 struct tracer_flags {
368         u32                     val;
369         struct tracer_opt       *opts;
370 };
371
372 /* Makes more easy to define a tracer opt */
373 #define TRACER_OPT(s, b)        .name = #s, .bit = b
374
375
376 /**
377  * struct tracer - a specific tracer and its callbacks to interact with debugfs
378  * @name: the name chosen to select it on the available_tracers file
379  * @init: called when one switches to this tracer (echo name > current_tracer)
380  * @reset: called when one switches to another tracer
381  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
382  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
383  * @open: called when the trace file is opened
384  * @pipe_open: called when the trace_pipe file is opened
385  * @wait_pipe: override how the user waits for traces on trace_pipe
386  * @close: called when the trace file is released
387  * @read: override the default read callback on trace_pipe
388  * @splice_read: override the default splice_read callback on trace_pipe
389  * @selftest: selftest to run on boot (see trace_selftest.c)
390  * @print_headers: override the first lines that describe your columns
391  * @print_line: callback that prints a trace
392  * @set_flag: signals one of your private flags changed (trace_options file)
393  * @flags: your private flags
394  */
395 struct tracer {
396         const char              *name;
397         int                     (*init)(struct trace_array *tr);
398         void                    (*reset)(struct trace_array *tr);
399         void                    (*start)(struct trace_array *tr);
400         void                    (*stop)(struct trace_array *tr);
401         void                    (*open)(struct trace_iterator *iter);
402         void                    (*pipe_open)(struct trace_iterator *iter);
403         void                    (*wait_pipe)(struct trace_iterator *iter);
404         void                    (*close)(struct trace_iterator *iter);
405         ssize_t                 (*read)(struct trace_iterator *iter,
406                                         struct file *filp, char __user *ubuf,
407                                         size_t cnt, loff_t *ppos);
408         ssize_t                 (*splice_read)(struct trace_iterator *iter,
409                                                struct file *filp,
410                                                loff_t *ppos,
411                                                struct pipe_inode_info *pipe,
412                                                size_t len,
413                                                unsigned int flags);
414 #ifdef CONFIG_FTRACE_STARTUP_TEST
415         int                     (*selftest)(struct tracer *trace,
416                                             struct trace_array *tr);
417 #endif
418         void                    (*print_header)(struct seq_file *m);
419         enum print_line_t       (*print_line)(struct trace_iterator *iter);
420         /* If you handled the flag setting, return 0 */
421         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
422         struct tracer           *next;
423         int                     print_max;
424         struct tracer_flags     *flags;
425         struct tracer_stat      *stats;
426 };
427
428
429 #define TRACE_PIPE_ALL_CPU      -1
430
431 int tracer_init(struct tracer *t, struct trace_array *tr);
432 int tracing_is_enabled(void);
433 void trace_wake_up(void);
434 void tracing_reset(struct trace_array *tr, int cpu);
435 void tracing_reset_online_cpus(struct trace_array *tr);
436 void tracing_reset_current(int cpu);
437 void tracing_reset_current_online_cpus(void);
438 int tracing_open_generic(struct inode *inode, struct file *filp);
439 struct dentry *trace_create_file(const char *name,
440                                  mode_t mode,
441                                  struct dentry *parent,
442                                  void *data,
443                                  const struct file_operations *fops);
444
445 struct dentry *tracing_init_dentry(void);
446 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
447
448 struct ring_buffer_event;
449
450 struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
451                                                     int type,
452                                                     unsigned long len,
453                                                     unsigned long flags,
454                                                     int pc);
455 void trace_buffer_unlock_commit(struct trace_array *tr,
456                                 struct ring_buffer_event *event,
457                                 unsigned long flags, int pc);
458
459 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
460                                                 struct trace_array_cpu *data);
461
462 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
463                                           int *ent_cpu, u64 *ent_ts);
464
465 void default_wait_pipe(struct trace_iterator *iter);
466 void poll_wait_pipe(struct trace_iterator *iter);
467
468 void ftrace(struct trace_array *tr,
469                             struct trace_array_cpu *data,
470                             unsigned long ip,
471                             unsigned long parent_ip,
472                             unsigned long flags, int pc);
473 void tracing_sched_switch_trace(struct trace_array *tr,
474                                 struct task_struct *prev,
475                                 struct task_struct *next,
476                                 unsigned long flags, int pc);
477
478 void tracing_sched_wakeup_trace(struct trace_array *tr,
479                                 struct task_struct *wakee,
480                                 struct task_struct *cur,
481                                 unsigned long flags, int pc);
482 void trace_special(struct trace_array *tr,
483                    struct trace_array_cpu *data,
484                    unsigned long arg1,
485                    unsigned long arg2,
486                    unsigned long arg3, int pc);
487 void trace_function(struct trace_array *tr,
488                     unsigned long ip,
489                     unsigned long parent_ip,
490                     unsigned long flags, int pc);
491
492 void trace_graph_return(struct ftrace_graph_ret *trace);
493 int trace_graph_entry(struct ftrace_graph_ent *trace);
494 void set_graph_array(struct trace_array *tr);
495
496 void tracing_start_cmdline_record(void);
497 void tracing_stop_cmdline_record(void);
498 void tracing_sched_switch_assign_trace(struct trace_array *tr);
499 void tracing_stop_sched_switch_record(void);
500 void tracing_start_sched_switch_record(void);
501 int register_tracer(struct tracer *type);
502 void unregister_tracer(struct tracer *type);
503
504 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
505
506 extern unsigned long tracing_max_latency;
507 extern unsigned long tracing_thresh;
508
509 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
510 void update_max_tr_single(struct trace_array *tr,
511                           struct task_struct *tsk, int cpu);
512
513 #ifdef CONFIG_STACKTRACE
514 void ftrace_trace_stack(struct trace_array *tr, unsigned long flags,
515                         int skip, int pc);
516
517 void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags,
518                             int pc);
519
520 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
521                    int pc);
522 #else
523 static inline void ftrace_trace_stack(struct trace_array *tr,
524                                       unsigned long flags, int skip, int pc)
525 {
526 }
527
528 static inline void ftrace_trace_userstack(struct trace_array *tr,
529                                           unsigned long flags, int pc)
530 {
531 }
532
533 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
534                                  int skip, int pc)
535 {
536 }
537 #endif /* CONFIG_STACKTRACE */
538
539 extern cycle_t ftrace_now(int cpu);
540
541 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
542 typedef void
543 (*tracer_switch_func_t)(void *private,
544                         void *__rq,
545                         struct task_struct *prev,
546                         struct task_struct *next);
547
548 struct tracer_switch_ops {
549         tracer_switch_func_t            func;
550         void                            *private;
551         struct tracer_switch_ops        *next;
552 };
553 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
554
555 extern void trace_find_cmdline(int pid, char comm[]);
556
557 #ifdef CONFIG_DYNAMIC_FTRACE
558 extern unsigned long ftrace_update_tot_cnt;
559 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
560 extern int DYN_FTRACE_TEST_NAME(void);
561 #endif
562
563 extern int ring_buffer_expanded;
564 extern bool tracing_selftest_disabled;
565 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
566
567 #ifdef CONFIG_FTRACE_STARTUP_TEST
568 extern int trace_selftest_startup_function(struct tracer *trace,
569                                            struct trace_array *tr);
570 extern int trace_selftest_startup_function_graph(struct tracer *trace,
571                                                  struct trace_array *tr);
572 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
573                                           struct trace_array *tr);
574 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
575                                              struct trace_array *tr);
576 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
577                                                  struct trace_array *tr);
578 extern int trace_selftest_startup_wakeup(struct tracer *trace,
579                                          struct trace_array *tr);
580 extern int trace_selftest_startup_nop(struct tracer *trace,
581                                          struct trace_array *tr);
582 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
583                                                struct trace_array *tr);
584 extern int trace_selftest_startup_sysprof(struct tracer *trace,
585                                                struct trace_array *tr);
586 extern int trace_selftest_startup_branch(struct tracer *trace,
587                                          struct trace_array *tr);
588 extern int trace_selftest_startup_hw_branches(struct tracer *trace,
589                                               struct trace_array *tr);
590 #endif /* CONFIG_FTRACE_STARTUP_TEST */
591
592 extern void *head_page(struct trace_array_cpu *data);
593 extern unsigned long long ns2usecs(cycle_t nsec);
594 extern int
595 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
596 extern int
597 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
598
599 extern unsigned long trace_flags;
600
601 extern int trace_clock_id;
602
603 /* Standard output formatting function used for function return traces */
604 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
605 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
606 extern enum print_line_t
607 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
608
609 #ifdef CONFIG_DYNAMIC_FTRACE
610 /* TODO: make this variable */
611 #define FTRACE_GRAPH_MAX_FUNCS          32
612 extern int ftrace_graph_count;
613 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
614
615 static inline int ftrace_graph_addr(unsigned long addr)
616 {
617         int i;
618
619         if (!ftrace_graph_count || test_tsk_trace_graph(current))
620                 return 1;
621
622         for (i = 0; i < ftrace_graph_count; i++) {
623                 if (addr == ftrace_graph_funcs[i])
624                         return 1;
625         }
626
627         return 0;
628 }
629 #else
630 static inline int ftrace_trace_addr(unsigned long addr)
631 {
632         return 1;
633 }
634 static inline int ftrace_graph_addr(unsigned long addr)
635 {
636         return 1;
637 }
638 #endif /* CONFIG_DYNAMIC_FTRACE */
639 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
640 static inline enum print_line_t
641 print_graph_function(struct trace_iterator *iter)
642 {
643         return TRACE_TYPE_UNHANDLED;
644 }
645 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
646
647 extern struct pid *ftrace_pid_trace;
648
649 #ifdef CONFIG_FUNCTION_TRACER
650 static inline int ftrace_trace_task(struct task_struct *task)
651 {
652         if (!ftrace_pid_trace)
653                 return 1;
654
655         return test_tsk_trace_trace(task);
656 }
657 #else
658 static inline int ftrace_trace_task(struct task_struct *task)
659 {
660         return 1;
661 }
662 #endif
663
664 /*
665  * trace_iterator_flags is an enumeration that defines bit
666  * positions into trace_flags that controls the output.
667  *
668  * NOTE: These bits must match the trace_options array in
669  *       trace.c.
670  */
671 enum trace_iterator_flags {
672         TRACE_ITER_PRINT_PARENT         = 0x01,
673         TRACE_ITER_SYM_OFFSET           = 0x02,
674         TRACE_ITER_SYM_ADDR             = 0x04,
675         TRACE_ITER_VERBOSE              = 0x08,
676         TRACE_ITER_RAW                  = 0x10,
677         TRACE_ITER_HEX                  = 0x20,
678         TRACE_ITER_BIN                  = 0x40,
679         TRACE_ITER_BLOCK                = 0x80,
680         TRACE_ITER_STACKTRACE           = 0x100,
681         TRACE_ITER_SCHED_TREE           = 0x200,
682         TRACE_ITER_PRINTK               = 0x400,
683         TRACE_ITER_PREEMPTONLY          = 0x800,
684         TRACE_ITER_BRANCH               = 0x1000,
685         TRACE_ITER_ANNOTATE             = 0x2000,
686         TRACE_ITER_USERSTACKTRACE       = 0x4000,
687         TRACE_ITER_SYM_USEROBJ          = 0x8000,
688         TRACE_ITER_PRINTK_MSGONLY       = 0x10000,
689         TRACE_ITER_CONTEXT_INFO         = 0x20000, /* Print pid/cpu/time */
690         TRACE_ITER_LATENCY_FMT          = 0x40000,
691         TRACE_ITER_SLEEP_TIME           = 0x80000,
692         TRACE_ITER_GRAPH_TIME           = 0x100000,
693 };
694
695 /*
696  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
697  * control the output of kernel symbols.
698  */
699 #define TRACE_ITER_SYM_MASK \
700         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
701
702 extern struct tracer nop_trace;
703
704 /**
705  * ftrace_preempt_disable - disable preemption scheduler safe
706  *
707  * When tracing can happen inside the scheduler, there exists
708  * cases that the tracing might happen before the need_resched
709  * flag is checked. If this happens and the tracer calls
710  * preempt_enable (after a disable), a schedule might take place
711  * causing an infinite recursion.
712  *
713  * To prevent this, we read the need_resched flag before
714  * disabling preemption. When we want to enable preemption we
715  * check the flag, if it is set, then we call preempt_enable_no_resched.
716  * Otherwise, we call preempt_enable.
717  *
718  * The rational for doing the above is that if need_resched is set
719  * and we have yet to reschedule, we are either in an atomic location
720  * (where we do not need to check for scheduling) or we are inside
721  * the scheduler and do not want to resched.
722  */
723 static inline int ftrace_preempt_disable(void)
724 {
725         int resched;
726
727         resched = need_resched();
728         preempt_disable_notrace();
729
730         return resched;
731 }
732
733 /**
734  * ftrace_preempt_enable - enable preemption scheduler safe
735  * @resched: the return value from ftrace_preempt_disable
736  *
737  * This is a scheduler safe way to enable preemption and not miss
738  * any preemption checks. The disabled saved the state of preemption.
739  * If resched is set, then we are either inside an atomic or
740  * are inside the scheduler (we would have already scheduled
741  * otherwise). In this case, we do not want to call normal
742  * preempt_enable, but preempt_enable_no_resched instead.
743  */
744 static inline void ftrace_preempt_enable(int resched)
745 {
746         if (resched)
747                 preempt_enable_no_resched_notrace();
748         else
749                 preempt_enable_notrace();
750 }
751
752 #ifdef CONFIG_BRANCH_TRACER
753 extern int enable_branch_tracing(struct trace_array *tr);
754 extern void disable_branch_tracing(void);
755 static inline int trace_branch_enable(struct trace_array *tr)
756 {
757         if (trace_flags & TRACE_ITER_BRANCH)
758                 return enable_branch_tracing(tr);
759         return 0;
760 }
761 static inline void trace_branch_disable(void)
762 {
763         /* due to races, always disable */
764         disable_branch_tracing();
765 }
766 #else
767 static inline int trace_branch_enable(struct trace_array *tr)
768 {
769         return 0;
770 }
771 static inline void trace_branch_disable(void)
772 {
773 }
774 #endif /* CONFIG_BRANCH_TRACER */
775
776 /* set ring buffers to default size if not already done so */
777 int tracing_update_buffers(void);
778
779 /* trace event type bit fields, not numeric */
780 enum {
781         TRACE_EVENT_TYPE_PRINTF         = 1,
782         TRACE_EVENT_TYPE_RAW            = 2,
783 };
784
785 struct ftrace_event_field {
786         struct list_head        link;
787         char                    *name;
788         char                    *type;
789         int                     filter_type;
790         int                     offset;
791         int                     size;
792         int                     is_signed;
793 };
794
795 struct event_filter {
796         int                     n_preds;
797         struct filter_pred      **preds;
798         char                    *filter_string;
799         bool                    no_reset;
800 };
801
802 struct event_subsystem {
803         struct list_head        list;
804         const char              *name;
805         struct dentry           *entry;
806         struct event_filter     *filter;
807         int                     nr_events;
808 };
809
810 struct filter_pred;
811
812 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
813                                  int val1, int val2);
814
815 struct filter_pred {
816         filter_pred_fn_t fn;
817         u64 val;
818         char str_val[MAX_FILTER_STR_VAL];
819         int str_len;
820         char *field_name;
821         int offset;
822         int not;
823         int op;
824         int pop_n;
825 };
826
827 extern void print_event_filter(struct ftrace_event_call *call,
828                                struct trace_seq *s);
829 extern int apply_event_filter(struct ftrace_event_call *call,
830                               char *filter_string);
831 extern int apply_subsystem_event_filter(struct event_subsystem *system,
832                                         char *filter_string);
833 extern void print_subsystem_event_filter(struct event_subsystem *system,
834                                          struct trace_seq *s);
835 extern int filter_assign_type(const char *type);
836
837 static inline int
838 filter_check_discard(struct ftrace_event_call *call, void *rec,
839                      struct ring_buffer *buffer,
840                      struct ring_buffer_event *event)
841 {
842         if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) {
843                 ring_buffer_discard_commit(buffer, event);
844                 return 1;
845         }
846
847         return 0;
848 }
849
850 #define DEFINE_COMPARISON_PRED(type)                                    \
851 static int filter_pred_##type(struct filter_pred *pred, void *event,    \
852                               int val1, int val2)                       \
853 {                                                                       \
854         type *addr = (type *)(event + pred->offset);                    \
855         type val = (type)pred->val;                                     \
856         int match = 0;                                                  \
857                                                                         \
858         switch (pred->op) {                                             \
859         case OP_LT:                                                     \
860                 match = (*addr < val);                                  \
861                 break;                                                  \
862         case OP_LE:                                                     \
863                 match = (*addr <= val);                                 \
864                 break;                                                  \
865         case OP_GT:                                                     \
866                 match = (*addr > val);                                  \
867                 break;                                                  \
868         case OP_GE:                                                     \
869                 match = (*addr >= val);                                 \
870                 break;                                                  \
871         default:                                                        \
872                 break;                                                  \
873         }                                                               \
874                                                                         \
875         return match;                                                   \
876 }
877
878 #define DEFINE_EQUALITY_PRED(size)                                      \
879 static int filter_pred_##size(struct filter_pred *pred, void *event,    \
880                               int val1, int val2)                       \
881 {                                                                       \
882         u##size *addr = (u##size *)(event + pred->offset);              \
883         u##size val = (u##size)pred->val;                               \
884         int match;                                                      \
885                                                                         \
886         match = (val == *addr) ^ pred->not;                             \
887                                                                         \
888         return match;                                                   \
889 }
890
891 extern struct mutex event_mutex;
892 extern struct list_head ftrace_events;
893
894 extern const char *__start___trace_bprintk_fmt[];
895 extern const char *__stop___trace_bprintk_fmt[];
896
897 #undef TRACE_EVENT_FORMAT
898 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
899         extern struct ftrace_event_call event_##call;
900 #undef TRACE_EVENT_FORMAT_NOFILTER
901 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
902 #include "trace_event_types.h"
903
904 #endif /* _LINUX_KERNEL_TRACE_H */