1 #ifndef _LINUX_KERNEL_TRACE_H
2 #define _LINUX_KERNEL_TRACE_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 <trace/kmemtrace.h>
13 #include <trace/power.h>
16 __TRACE_FIRST_TYPE
= 0,
43 * The trace entry - the most basic unit of tracing. This is what
44 * is printed in the end as a single line in the trace output, such as:
46 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
51 unsigned char preempt_count
;
57 * Function trace entry - function address and parent function addres:
60 struct trace_entry ent
;
62 unsigned long parent_ip
;
65 /* Function call entry */
66 struct ftrace_graph_ent_entry
{
67 struct trace_entry ent
;
68 struct ftrace_graph_ent graph_ent
;
71 /* Function return entry */
72 struct ftrace_graph_ret_entry
{
73 struct trace_entry ent
;
74 struct ftrace_graph_ret ret
;
76 extern struct tracer boot_tracer
;
79 * Context switch trace entry - which task (and prio) we switched from/to:
81 struct ctx_switch_entry
{
82 struct trace_entry ent
;
83 unsigned int prev_pid
;
84 unsigned char prev_prio
;
85 unsigned char prev_state
;
86 unsigned int next_pid
;
87 unsigned char next_prio
;
88 unsigned char next_state
;
89 unsigned int next_cpu
;
93 * Special (free-form) trace entry:
95 struct special_entry
{
96 struct trace_entry ent
;
106 #define FTRACE_STACK_ENTRIES 8
109 struct trace_entry ent
;
110 unsigned long caller
[FTRACE_STACK_ENTRIES
];
113 struct userstack_entry
{
114 struct trace_entry ent
;
115 unsigned long caller
[FTRACE_STACK_ENTRIES
];
119 * trace_printk entry:
121 struct bprint_entry
{
122 struct trace_entry ent
;
130 struct trace_entry ent
;
136 #define TRACE_OLD_SIZE 88
138 struct trace_field_cont
{
140 /* Temporary till we get rid of this completely */
141 char buf
[TRACE_OLD_SIZE
- 1];
144 struct trace_mmiotrace_rw
{
145 struct trace_entry ent
;
146 struct mmiotrace_rw rw
;
149 struct trace_mmiotrace_map
{
150 struct trace_entry ent
;
151 struct mmiotrace_map map
;
154 struct trace_boot_call
{
155 struct trace_entry ent
;
156 struct boot_trace_call boot_call
;
159 struct trace_boot_ret
{
160 struct trace_entry ent
;
161 struct boot_trace_ret boot_ret
;
164 #define TRACE_FUNC_SIZE 30
165 #define TRACE_FILE_SIZE 20
166 struct trace_branch
{
167 struct trace_entry ent
;
169 char func
[TRACE_FUNC_SIZE
+1];
170 char file
[TRACE_FILE_SIZE
+1];
174 struct hw_branch_entry
{
175 struct trace_entry ent
;
181 struct trace_entry ent
;
182 struct power_trace state_data
;
185 struct kmemtrace_alloc_entry
{
186 struct trace_entry ent
;
187 enum kmemtrace_type_id type_id
;
188 unsigned long call_site
;
196 struct kmemtrace_free_entry
{
197 struct trace_entry ent
;
198 enum kmemtrace_type_id type_id
;
199 unsigned long call_site
;
204 * trace_flag_type is an enumeration that holds different
205 * states when a trace occurs. These are:
206 * IRQS_OFF - interrupts were disabled
207 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
208 * NEED_RESCED - reschedule is requested
209 * HARDIRQ - inside an interrupt handler
210 * SOFTIRQ - inside a softirq handler
212 enum trace_flag_type
{
213 TRACE_FLAG_IRQS_OFF
= 0x01,
214 TRACE_FLAG_IRQS_NOSUPPORT
= 0x02,
215 TRACE_FLAG_NEED_RESCHED
= 0x04,
216 TRACE_FLAG_HARDIRQ
= 0x08,
217 TRACE_FLAG_SOFTIRQ
= 0x10,
220 #define TRACE_BUF_SIZE 1024
223 * The CPU trace array - it consists of thousands of trace entries
224 * plus some other descriptor data: (for example which task started
227 struct trace_array_cpu
{
229 void *buffer_page
; /* ring buffer spare */
231 /* these fields get copied into max-trace: */
232 unsigned long trace_idx
;
233 unsigned long overrun
;
234 unsigned long saved_latency
;
235 unsigned long critical_start
;
236 unsigned long critical_end
;
237 unsigned long critical_sequence
;
239 unsigned long policy
;
240 unsigned long rt_priority
;
241 cycle_t preempt_timestamp
;
244 char comm
[TASK_COMM_LEN
];
247 struct trace_iterator
;
250 * The trace array - an array of per-CPU trace arrays. This is the
251 * highest level data structure that individual tracers deal with.
252 * They have on/off state as well:
255 struct ring_buffer
*buffer
;
256 unsigned long entries
;
259 struct task_struct
*waiter
;
260 struct trace_array_cpu
*data
[NR_CPUS
];
263 #define FTRACE_CMP_TYPE(var, type) \
264 __builtin_types_compatible_p(typeof(var), type *)
267 #define IF_ASSIGN(var, entry, etype, id) \
268 if (FTRACE_CMP_TYPE(var, etype)) { \
269 var = (typeof(var))(entry); \
270 WARN_ON(id && (entry)->type != id); \
274 /* Will cause compile errors if type is not found. */
275 extern void __ftrace_bad_type(void);
278 * The trace_assign_type is a verifier that the entry type is
279 * the same as the type being assigned. To add new types simply
280 * add a line with the following format:
282 * IF_ASSIGN(var, ent, type, id);
284 * Where "type" is the trace type that includes the trace_entry
285 * as the "ent" item. And "id" is the trace identifier that is
286 * used in the trace_type enum.
288 * If the type can have more than one id, then use zero.
290 #define trace_assign_type(var, ent) \
292 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
293 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
294 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
295 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
296 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
297 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
298 IF_ASSIGN(var, ent, struct special_entry, 0); \
299 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
301 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
303 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
304 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
305 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
306 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
308 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
310 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
311 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
312 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
314 IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
316 __ftrace_bad_type(); \
319 /* Return values for print_line callback */
321 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
322 TRACE_TYPE_HANDLED
= 1,
323 TRACE_TYPE_UNHANDLED
= 2, /* Relay to other output functions */
324 TRACE_TYPE_NO_CONSUME
= 3 /* Handled but ask to not consume */
329 * An option specific to a tracer. This is a boolean value.
330 * The bit is the bit index that sets its value on the
331 * flags value in struct tracer_flags.
334 const char *name
; /* Will appear on the trace_options file */
335 u32 bit
; /* Mask assigned in val field in tracer_flags */
339 * The set of specific options for a tracer. Your tracer
340 * have to set the initial value of the flags val.
342 struct tracer_flags
{
344 struct tracer_opt
*opts
;
347 /* Makes more easy to define a tracer opt */
348 #define TRACER_OPT(s, b) .name = #s, .bit = b
352 * struct tracer - a specific tracer and its callbacks to interact with debugfs
353 * @name: the name chosen to select it on the available_tracers file
354 * @init: called when one switches to this tracer (echo name > current_tracer)
355 * @reset: called when one switches to another tracer
356 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
357 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
358 * @open: called when the trace file is opened
359 * @pipe_open: called when the trace_pipe file is opened
360 * @wait_pipe: override how the user waits for traces on trace_pipe
361 * @close: called when the trace file is released
362 * @read: override the default read callback on trace_pipe
363 * @splice_read: override the default splice_read callback on trace_pipe
364 * @selftest: selftest to run on boot (see trace_selftest.c)
365 * @print_headers: override the first lines that describe your columns
366 * @print_line: callback that prints a trace
367 * @set_flag: signals one of your private flags changed (trace_options file)
368 * @flags: your private flags
372 int (*init
)(struct trace_array
*tr
);
373 void (*reset
)(struct trace_array
*tr
);
374 void (*start
)(struct trace_array
*tr
);
375 void (*stop
)(struct trace_array
*tr
);
376 void (*open
)(struct trace_iterator
*iter
);
377 void (*pipe_open
)(struct trace_iterator
*iter
);
378 void (*wait_pipe
)(struct trace_iterator
*iter
);
379 void (*close
)(struct trace_iterator
*iter
);
380 ssize_t (*read
)(struct trace_iterator
*iter
,
381 struct file
*filp
, char __user
*ubuf
,
382 size_t cnt
, loff_t
*ppos
);
383 ssize_t (*splice_read
)(struct trace_iterator
*iter
,
386 struct pipe_inode_info
*pipe
,
389 #ifdef CONFIG_FTRACE_STARTUP_TEST
390 int (*selftest
)(struct tracer
*trace
,
391 struct trace_array
*tr
);
393 void (*print_header
)(struct seq_file
*m
);
394 enum print_line_t (*print_line
)(struct trace_iterator
*iter
);
395 /* If you handled the flag setting, return 0 */
396 int (*set_flag
)(u32 old_flags
, u32 bit
, int set
);
399 struct tracer_flags
*flags
;
400 struct tracer_stat
*stats
;
404 unsigned char buffer
[PAGE_SIZE
];
406 unsigned int readpos
;
410 trace_seq_init(struct trace_seq
*s
)
417 #define TRACE_PIPE_ALL_CPU -1
420 * Trace iterator - used by printout routines who present trace
421 * results to users and which routines might sleep, etc:
423 struct trace_iterator
{
424 struct trace_array
*tr
;
425 struct tracer
*trace
;
429 struct ring_buffer_iter
*buffer_iter
[NR_CPUS
];
431 /* The below is zeroed out in pipe_read */
432 struct trace_seq seq
;
433 struct trace_entry
*ent
;
437 unsigned long iter_flags
;
441 cpumask_var_t started
;
444 int tracer_init(struct tracer
*t
, struct trace_array
*tr
);
445 int tracing_is_enabled(void);
446 void trace_wake_up(void);
447 void tracing_reset(struct trace_array
*tr
, int cpu
);
448 void tracing_reset_online_cpus(struct trace_array
*tr
);
449 int tracing_open_generic(struct inode
*inode
, struct file
*filp
);
450 struct dentry
*tracing_init_dentry(void);
451 void init_tracer_sysprof_debugfs(struct dentry
*d_tracer
);
453 struct ring_buffer_event
;
455 struct ring_buffer_event
*trace_buffer_lock_reserve(struct trace_array
*tr
,
460 void trace_buffer_unlock_commit(struct trace_array
*tr
,
461 struct ring_buffer_event
*event
,
462 unsigned long flags
, int pc
);
464 struct ring_buffer_event
*
465 trace_current_buffer_lock_reserve(unsigned char type
, unsigned long len
,
466 unsigned long flags
, int pc
);
467 void trace_current_buffer_unlock_commit(struct ring_buffer_event
*event
,
468 unsigned long flags
, int pc
);
470 struct trace_entry
*tracing_get_trace_entry(struct trace_array
*tr
,
471 struct trace_array_cpu
*data
);
473 struct trace_entry
*trace_find_next_entry(struct trace_iterator
*iter
,
474 int *ent_cpu
, u64
*ent_ts
);
476 void tracing_generic_entry_update(struct trace_entry
*entry
,
480 void default_wait_pipe(struct trace_iterator
*iter
);
481 void poll_wait_pipe(struct trace_iterator
*iter
);
483 void ftrace(struct trace_array
*tr
,
484 struct trace_array_cpu
*data
,
486 unsigned long parent_ip
,
487 unsigned long flags
, int pc
);
488 void tracing_sched_switch_trace(struct trace_array
*tr
,
489 struct task_struct
*prev
,
490 struct task_struct
*next
,
491 unsigned long flags
, int pc
);
492 void tracing_record_cmdline(struct task_struct
*tsk
);
494 void tracing_sched_wakeup_trace(struct trace_array
*tr
,
495 struct task_struct
*wakee
,
496 struct task_struct
*cur
,
497 unsigned long flags
, int pc
);
498 void trace_special(struct trace_array
*tr
,
499 struct trace_array_cpu
*data
,
502 unsigned long arg3
, int pc
);
503 void trace_function(struct trace_array
*tr
,
505 unsigned long parent_ip
,
506 unsigned long flags
, int pc
);
508 void trace_graph_return(struct ftrace_graph_ret
*trace
);
509 int trace_graph_entry(struct ftrace_graph_ent
*trace
);
511 void tracing_start_cmdline_record(void);
512 void tracing_stop_cmdline_record(void);
513 void tracing_sched_switch_assign_trace(struct trace_array
*tr
);
514 void tracing_stop_sched_switch_record(void);
515 void tracing_start_sched_switch_record(void);
516 int register_tracer(struct tracer
*type
);
517 void unregister_tracer(struct tracer
*type
);
519 extern unsigned long nsecs_to_usecs(unsigned long nsecs
);
521 extern unsigned long tracing_max_latency
;
522 extern unsigned long tracing_thresh
;
524 void update_max_tr(struct trace_array
*tr
, struct task_struct
*tsk
, int cpu
);
525 void update_max_tr_single(struct trace_array
*tr
,
526 struct task_struct
*tsk
, int cpu
);
528 void __trace_stack(struct trace_array
*tr
,
532 extern cycle_t
ftrace_now(int cpu
);
534 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
536 (*tracer_switch_func_t
)(void *private,
538 struct task_struct
*prev
,
539 struct task_struct
*next
);
541 struct tracer_switch_ops
{
542 tracer_switch_func_t func
;
544 struct tracer_switch_ops
*next
;
546 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
548 extern char *trace_find_cmdline(int pid
);
550 #ifdef CONFIG_DYNAMIC_FTRACE
551 extern unsigned long ftrace_update_tot_cnt
;
552 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
553 extern int DYN_FTRACE_TEST_NAME(void);
556 #ifdef CONFIG_FTRACE_STARTUP_TEST
557 extern int trace_selftest_startup_function(struct tracer
*trace
,
558 struct trace_array
*tr
);
559 extern int trace_selftest_startup_function_graph(struct tracer
*trace
,
560 struct trace_array
*tr
);
561 extern int trace_selftest_startup_irqsoff(struct tracer
*trace
,
562 struct trace_array
*tr
);
563 extern int trace_selftest_startup_preemptoff(struct tracer
*trace
,
564 struct trace_array
*tr
);
565 extern int trace_selftest_startup_preemptirqsoff(struct tracer
*trace
,
566 struct trace_array
*tr
);
567 extern int trace_selftest_startup_wakeup(struct tracer
*trace
,
568 struct trace_array
*tr
);
569 extern int trace_selftest_startup_nop(struct tracer
*trace
,
570 struct trace_array
*tr
);
571 extern int trace_selftest_startup_sched_switch(struct tracer
*trace
,
572 struct trace_array
*tr
);
573 extern int trace_selftest_startup_sysprof(struct tracer
*trace
,
574 struct trace_array
*tr
);
575 extern int trace_selftest_startup_branch(struct tracer
*trace
,
576 struct trace_array
*tr
);
577 #endif /* CONFIG_FTRACE_STARTUP_TEST */
579 extern void *head_page(struct trace_array_cpu
*data
);
580 extern long ns2usecs(cycle_t nsec
);
582 trace_vbprintk(unsigned long ip
, int depth
, const char *fmt
, va_list args
);
584 trace_vprintk(unsigned long ip
, int depth
, const char *fmt
, va_list args
);
586 extern unsigned long trace_flags
;
588 /* Standard output formatting function used for function return traces */
589 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
590 extern enum print_line_t
print_graph_function(struct trace_iterator
*iter
);
592 #ifdef CONFIG_DYNAMIC_FTRACE
593 /* TODO: make this variable */
594 #define FTRACE_GRAPH_MAX_FUNCS 32
595 extern int ftrace_graph_count
;
596 extern unsigned long ftrace_graph_funcs
[FTRACE_GRAPH_MAX_FUNCS
];
598 static inline int ftrace_graph_addr(unsigned long addr
)
602 if (!ftrace_graph_count
|| test_tsk_trace_graph(current
))
605 for (i
= 0; i
< ftrace_graph_count
; i
++) {
606 if (addr
== ftrace_graph_funcs
[i
])
613 static inline int ftrace_trace_addr(unsigned long addr
)
617 static inline int ftrace_graph_addr(unsigned long addr
)
621 #endif /* CONFIG_DYNAMIC_FTRACE */
623 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
624 static inline enum print_line_t
625 print_graph_function(struct trace_iterator
*iter
)
627 return TRACE_TYPE_UNHANDLED
;
629 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
631 extern struct pid
*ftrace_pid_trace
;
633 static inline int ftrace_trace_task(struct task_struct
*task
)
635 if (!ftrace_pid_trace
)
638 return test_tsk_trace_trace(task
);
642 * trace_iterator_flags is an enumeration that defines bit
643 * positions into trace_flags that controls the output.
645 * NOTE: These bits must match the trace_options array in
648 enum trace_iterator_flags
{
649 TRACE_ITER_PRINT_PARENT
= 0x01,
650 TRACE_ITER_SYM_OFFSET
= 0x02,
651 TRACE_ITER_SYM_ADDR
= 0x04,
652 TRACE_ITER_VERBOSE
= 0x08,
653 TRACE_ITER_RAW
= 0x10,
654 TRACE_ITER_HEX
= 0x20,
655 TRACE_ITER_BIN
= 0x40,
656 TRACE_ITER_BLOCK
= 0x80,
657 TRACE_ITER_STACKTRACE
= 0x100,
658 TRACE_ITER_SCHED_TREE
= 0x200,
659 TRACE_ITER_PRINTK
= 0x400,
660 TRACE_ITER_PREEMPTONLY
= 0x800,
661 TRACE_ITER_BRANCH
= 0x1000,
662 TRACE_ITER_ANNOTATE
= 0x2000,
663 TRACE_ITER_USERSTACKTRACE
= 0x4000,
664 TRACE_ITER_SYM_USEROBJ
= 0x8000,
665 TRACE_ITER_PRINTK_MSGONLY
= 0x10000,
666 TRACE_ITER_CONTEXT_INFO
= 0x20000, /* Print pid/cpu/time */
667 TRACE_ITER_LATENCY_FMT
= 0x40000,
671 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
672 * control the output of kernel symbols.
674 #define TRACE_ITER_SYM_MASK \
675 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
677 extern struct tracer nop_trace
;
680 * ftrace_preempt_disable - disable preemption scheduler safe
682 * When tracing can happen inside the scheduler, there exists
683 * cases that the tracing might happen before the need_resched
684 * flag is checked. If this happens and the tracer calls
685 * preempt_enable (after a disable), a schedule might take place
686 * causing an infinite recursion.
688 * To prevent this, we read the need_resched flag before
689 * disabling preemption. When we want to enable preemption we
690 * check the flag, if it is set, then we call preempt_enable_no_resched.
691 * Otherwise, we call preempt_enable.
693 * The rational for doing the above is that if need_resched is set
694 * and we have yet to reschedule, we are either in an atomic location
695 * (where we do not need to check for scheduling) or we are inside
696 * the scheduler and do not want to resched.
698 static inline int ftrace_preempt_disable(void)
702 resched
= need_resched();
703 preempt_disable_notrace();
709 * ftrace_preempt_enable - enable preemption scheduler safe
710 * @resched: the return value from ftrace_preempt_disable
712 * This is a scheduler safe way to enable preemption and not miss
713 * any preemption checks. The disabled saved the state of preemption.
714 * If resched is set, then we are either inside an atomic or
715 * are inside the scheduler (we would have already scheduled
716 * otherwise). In this case, we do not want to call normal
717 * preempt_enable, but preempt_enable_no_resched instead.
719 static inline void ftrace_preempt_enable(int resched
)
722 preempt_enable_no_resched_notrace();
724 preempt_enable_notrace();
727 #ifdef CONFIG_BRANCH_TRACER
728 extern int enable_branch_tracing(struct trace_array
*tr
);
729 extern void disable_branch_tracing(void);
730 static inline int trace_branch_enable(struct trace_array
*tr
)
732 if (trace_flags
& TRACE_ITER_BRANCH
)
733 return enable_branch_tracing(tr
);
736 static inline void trace_branch_disable(void)
738 /* due to races, always disable */
739 disable_branch_tracing();
742 static inline int trace_branch_enable(struct trace_array
*tr
)
746 static inline void trace_branch_disable(void)
749 #endif /* CONFIG_BRANCH_TRACER */
751 /* set ring buffers to default size if not already done so */
752 int tracing_update_buffers(void);
754 /* trace event type bit fields, not numeric */
756 TRACE_EVENT_TYPE_PRINTF
= 1,
757 TRACE_EVENT_TYPE_RAW
= 2,
760 struct ftrace_event_call
{
765 int (*regfunc
)(void);
766 void (*unregfunc
)(void);
768 int (*raw_init
)(void);
769 int (*show_format
)(struct trace_seq
*s
);
772 void event_trace_printk(unsigned long ip
, const char *fmt
, ...);
773 extern struct ftrace_event_call __start_ftrace_events
[];
774 extern struct ftrace_event_call __stop_ftrace_events
[];
776 #endif /* _LINUX_KERNEL_TRACE_H */