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,
42 * The trace entry - the most basic unit of tracing. This is what
43 * is printed in the end as a single line in the trace output, such as:
45 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
50 unsigned char preempt_count
;
56 * Function trace entry - function address and parent function addres:
59 struct trace_entry ent
;
61 unsigned long parent_ip
;
64 /* Function call entry */
65 struct ftrace_graph_ent_entry
{
66 struct trace_entry ent
;
67 struct ftrace_graph_ent graph_ent
;
70 /* Function return entry */
71 struct ftrace_graph_ret_entry
{
72 struct trace_entry ent
;
73 struct ftrace_graph_ret ret
;
75 extern struct tracer boot_tracer
;
78 * Context switch trace entry - which task (and prio) we switched from/to:
80 struct ctx_switch_entry
{
81 struct trace_entry ent
;
82 unsigned int prev_pid
;
83 unsigned char prev_prio
;
84 unsigned char prev_state
;
85 unsigned int next_pid
;
86 unsigned char next_prio
;
87 unsigned char next_state
;
88 unsigned int next_cpu
;
92 * Special (free-form) trace entry:
94 struct special_entry
{
95 struct trace_entry ent
;
105 #define FTRACE_STACK_ENTRIES 8
108 struct trace_entry ent
;
109 unsigned long caller
[FTRACE_STACK_ENTRIES
];
112 struct userstack_entry
{
113 struct trace_entry ent
;
114 unsigned long caller
[FTRACE_STACK_ENTRIES
];
118 * trace_printk entry:
121 struct trace_entry ent
;
128 #define TRACE_OLD_SIZE 88
130 struct trace_field_cont
{
132 /* Temporary till we get rid of this completely */
133 char buf
[TRACE_OLD_SIZE
- 1];
136 struct trace_mmiotrace_rw
{
137 struct trace_entry ent
;
138 struct mmiotrace_rw rw
;
141 struct trace_mmiotrace_map
{
142 struct trace_entry ent
;
143 struct mmiotrace_map map
;
146 struct trace_boot_call
{
147 struct trace_entry ent
;
148 struct boot_trace_call boot_call
;
151 struct trace_boot_ret
{
152 struct trace_entry ent
;
153 struct boot_trace_ret boot_ret
;
156 #define TRACE_FUNC_SIZE 30
157 #define TRACE_FILE_SIZE 20
158 struct trace_branch
{
159 struct trace_entry ent
;
161 char func
[TRACE_FUNC_SIZE
+1];
162 char file
[TRACE_FILE_SIZE
+1];
166 struct hw_branch_entry
{
167 struct trace_entry ent
;
173 struct trace_entry ent
;
174 struct power_trace state_data
;
177 struct kmemtrace_alloc_entry
{
178 struct trace_entry ent
;
179 enum kmemtrace_type_id type_id
;
180 unsigned long call_site
;
188 struct kmemtrace_free_entry
{
189 struct trace_entry ent
;
190 enum kmemtrace_type_id type_id
;
191 unsigned long call_site
;
196 * trace_flag_type is an enumeration that holds different
197 * states when a trace occurs. These are:
198 * IRQS_OFF - interrupts were disabled
199 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
200 * NEED_RESCED - reschedule is requested
201 * HARDIRQ - inside an interrupt handler
202 * SOFTIRQ - inside a softirq handler
204 enum trace_flag_type
{
205 TRACE_FLAG_IRQS_OFF
= 0x01,
206 TRACE_FLAG_IRQS_NOSUPPORT
= 0x02,
207 TRACE_FLAG_NEED_RESCHED
= 0x04,
208 TRACE_FLAG_HARDIRQ
= 0x08,
209 TRACE_FLAG_SOFTIRQ
= 0x10,
212 #define TRACE_BUF_SIZE 1024
215 * The CPU trace array - it consists of thousands of trace entries
216 * plus some other descriptor data: (for example which task started
219 struct trace_array_cpu
{
221 void *buffer_page
; /* ring buffer spare */
223 /* these fields get copied into max-trace: */
224 unsigned long trace_idx
;
225 unsigned long overrun
;
226 unsigned long saved_latency
;
227 unsigned long critical_start
;
228 unsigned long critical_end
;
229 unsigned long critical_sequence
;
231 unsigned long policy
;
232 unsigned long rt_priority
;
233 cycle_t preempt_timestamp
;
236 char comm
[TASK_COMM_LEN
];
239 struct trace_iterator
;
242 * The trace array - an array of per-CPU trace arrays. This is the
243 * highest level data structure that individual tracers deal with.
244 * They have on/off state as well:
247 struct ring_buffer
*buffer
;
248 unsigned long entries
;
251 struct task_struct
*waiter
;
252 struct trace_array_cpu
*data
[NR_CPUS
];
255 #define FTRACE_CMP_TYPE(var, type) \
256 __builtin_types_compatible_p(typeof(var), type *)
259 #define IF_ASSIGN(var, entry, etype, id) \
260 if (FTRACE_CMP_TYPE(var, etype)) { \
261 var = (typeof(var))(entry); \
262 WARN_ON(id && (entry)->type != id); \
266 /* Will cause compile errors if type is not found. */
267 extern void __ftrace_bad_type(void);
270 * The trace_assign_type is a verifier that the entry type is
271 * the same as the type being assigned. To add new types simply
272 * add a line with the following format:
274 * IF_ASSIGN(var, ent, type, id);
276 * Where "type" is the trace type that includes the trace_entry
277 * as the "ent" item. And "id" is the trace identifier that is
278 * used in the trace_type enum.
280 * If the type can have more than one id, then use zero.
282 #define trace_assign_type(var, ent) \
284 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
285 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
286 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
287 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
288 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
289 IF_ASSIGN(var, ent, struct special_entry, 0); \
290 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
292 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
294 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
295 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
296 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
297 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
299 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
301 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
302 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
303 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
305 IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
307 __ftrace_bad_type(); \
310 /* Return values for print_line callback */
312 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
313 TRACE_TYPE_HANDLED
= 1,
314 TRACE_TYPE_UNHANDLED
= 2, /* Relay to other output functions */
315 TRACE_TYPE_NO_CONSUME
= 3 /* Handled but ask to not consume */
320 * An option specific to a tracer. This is a boolean value.
321 * The bit is the bit index that sets its value on the
322 * flags value in struct tracer_flags.
325 const char *name
; /* Will appear on the trace_options file */
326 u32 bit
; /* Mask assigned in val field in tracer_flags */
330 * The set of specific options for a tracer. Your tracer
331 * have to set the initial value of the flags val.
333 struct tracer_flags
{
335 struct tracer_opt
*opts
;
338 /* Makes more easy to define a tracer opt */
339 #define TRACER_OPT(s, b) .name = #s, .bit = b
343 * struct tracer - a specific tracer and its callbacks to interact with debugfs
344 * @name: the name chosen to select it on the available_tracers file
345 * @init: called when one switches to this tracer (echo name > current_tracer)
346 * @reset: called when one switches to another tracer
347 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
348 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
349 * @open: called when the trace file is opened
350 * @pipe_open: called when the trace_pipe file is opened
351 * @wait_pipe: override how the user waits for traces on trace_pipe
352 * @close: called when the trace file is released
353 * @read: override the default read callback on trace_pipe
354 * @splice_read: override the default splice_read callback on trace_pipe
355 * @selftest: selftest to run on boot (see trace_selftest.c)
356 * @print_headers: override the first lines that describe your columns
357 * @print_line: callback that prints a trace
358 * @set_flag: signals one of your private flags changed (trace_options file)
359 * @flags: your private flags
363 int (*init
)(struct trace_array
*tr
);
364 void (*reset
)(struct trace_array
*tr
);
365 void (*start
)(struct trace_array
*tr
);
366 void (*stop
)(struct trace_array
*tr
);
367 void (*open
)(struct trace_iterator
*iter
);
368 void (*pipe_open
)(struct trace_iterator
*iter
);
369 void (*wait_pipe
)(struct trace_iterator
*iter
);
370 void (*close
)(struct trace_iterator
*iter
);
371 ssize_t (*read
)(struct trace_iterator
*iter
,
372 struct file
*filp
, char __user
*ubuf
,
373 size_t cnt
, loff_t
*ppos
);
374 ssize_t (*splice_read
)(struct trace_iterator
*iter
,
377 struct pipe_inode_info
*pipe
,
380 #ifdef CONFIG_FTRACE_STARTUP_TEST
381 int (*selftest
)(struct tracer
*trace
,
382 struct trace_array
*tr
);
384 void (*print_header
)(struct seq_file
*m
);
385 enum print_line_t (*print_line
)(struct trace_iterator
*iter
);
386 /* If you handled the flag setting, return 0 */
387 int (*set_flag
)(u32 old_flags
, u32 bit
, int set
);
390 struct tracer_flags
*flags
;
391 struct tracer_stat
*stats
;
395 unsigned char buffer
[PAGE_SIZE
];
397 unsigned int readpos
;
401 trace_seq_init(struct trace_seq
*s
)
408 #define TRACE_PIPE_ALL_CPU -1
411 * Trace iterator - used by printout routines who present trace
412 * results to users and which routines might sleep, etc:
414 struct trace_iterator
{
415 struct trace_array
*tr
;
416 struct tracer
*trace
;
420 struct ring_buffer_iter
*buffer_iter
[NR_CPUS
];
422 /* The below is zeroed out in pipe_read */
423 struct trace_seq seq
;
424 struct trace_entry
*ent
;
428 unsigned long iter_flags
;
432 cpumask_var_t started
;
435 int tracer_init(struct tracer
*t
, struct trace_array
*tr
);
436 int tracing_is_enabled(void);
437 void trace_wake_up(void);
438 void tracing_reset(struct trace_array
*tr
, int cpu
);
439 void tracing_reset_online_cpus(struct trace_array
*tr
);
440 int tracing_open_generic(struct inode
*inode
, struct file
*filp
);
441 struct dentry
*tracing_init_dentry(void);
442 void init_tracer_sysprof_debugfs(struct dentry
*d_tracer
);
444 struct ring_buffer_event
;
446 struct ring_buffer_event
*trace_buffer_lock_reserve(struct trace_array
*tr
,
451 void trace_buffer_unlock_commit(struct trace_array
*tr
,
452 struct ring_buffer_event
*event
,
453 unsigned long flags
, int pc
);
455 struct ring_buffer_event
*
456 trace_current_buffer_lock_reserve(unsigned char type
, unsigned long len
,
457 unsigned long flags
, int pc
);
458 void trace_current_buffer_unlock_commit(struct ring_buffer_event
*event
,
459 unsigned long flags
, int pc
);
461 struct trace_entry
*tracing_get_trace_entry(struct trace_array
*tr
,
462 struct trace_array_cpu
*data
);
464 struct trace_entry
*trace_find_next_entry(struct trace_iterator
*iter
,
465 int *ent_cpu
, u64
*ent_ts
);
467 void tracing_generic_entry_update(struct trace_entry
*entry
,
471 void default_wait_pipe(struct trace_iterator
*iter
);
472 void poll_wait_pipe(struct trace_iterator
*iter
);
474 void ftrace(struct trace_array
*tr
,
475 struct trace_array_cpu
*data
,
477 unsigned long parent_ip
,
478 unsigned long flags
, int pc
);
479 void tracing_sched_switch_trace(struct trace_array
*tr
,
480 struct task_struct
*prev
,
481 struct task_struct
*next
,
482 unsigned long flags
, int pc
);
483 void tracing_record_cmdline(struct task_struct
*tsk
);
485 void tracing_sched_wakeup_trace(struct trace_array
*tr
,
486 struct task_struct
*wakee
,
487 struct task_struct
*cur
,
488 unsigned long flags
, int pc
);
489 void trace_special(struct trace_array
*tr
,
490 struct trace_array_cpu
*data
,
493 unsigned long arg3
, int pc
);
494 void trace_function(struct trace_array
*tr
,
496 unsigned long parent_ip
,
497 unsigned long flags
, int pc
);
499 void trace_graph_return(struct ftrace_graph_ret
*trace
);
500 int trace_graph_entry(struct ftrace_graph_ent
*trace
);
502 void tracing_start_cmdline_record(void);
503 void tracing_stop_cmdline_record(void);
504 void tracing_sched_switch_assign_trace(struct trace_array
*tr
);
505 void tracing_stop_sched_switch_record(void);
506 void tracing_start_sched_switch_record(void);
507 int register_tracer(struct tracer
*type
);
508 void unregister_tracer(struct tracer
*type
);
510 extern unsigned long nsecs_to_usecs(unsigned long nsecs
);
512 extern unsigned long tracing_max_latency
;
513 extern unsigned long tracing_thresh
;
515 void update_max_tr(struct trace_array
*tr
, struct task_struct
*tsk
, int cpu
);
516 void update_max_tr_single(struct trace_array
*tr
,
517 struct task_struct
*tsk
, int cpu
);
519 void __trace_stack(struct trace_array
*tr
,
523 extern cycle_t
ftrace_now(int cpu
);
525 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
527 (*tracer_switch_func_t
)(void *private,
529 struct task_struct
*prev
,
530 struct task_struct
*next
);
532 struct tracer_switch_ops
{
533 tracer_switch_func_t func
;
535 struct tracer_switch_ops
*next
;
537 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
539 extern char *trace_find_cmdline(int pid
);
541 #ifdef CONFIG_DYNAMIC_FTRACE
542 extern unsigned long ftrace_update_tot_cnt
;
543 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
544 extern int DYN_FTRACE_TEST_NAME(void);
547 #ifdef CONFIG_FTRACE_STARTUP_TEST
548 extern int trace_selftest_startup_function(struct tracer
*trace
,
549 struct trace_array
*tr
);
550 extern int trace_selftest_startup_function_graph(struct tracer
*trace
,
551 struct trace_array
*tr
);
552 extern int trace_selftest_startup_irqsoff(struct tracer
*trace
,
553 struct trace_array
*tr
);
554 extern int trace_selftest_startup_preemptoff(struct tracer
*trace
,
555 struct trace_array
*tr
);
556 extern int trace_selftest_startup_preemptirqsoff(struct tracer
*trace
,
557 struct trace_array
*tr
);
558 extern int trace_selftest_startup_wakeup(struct tracer
*trace
,
559 struct trace_array
*tr
);
560 extern int trace_selftest_startup_nop(struct tracer
*trace
,
561 struct trace_array
*tr
);
562 extern int trace_selftest_startup_sched_switch(struct tracer
*trace
,
563 struct trace_array
*tr
);
564 extern int trace_selftest_startup_sysprof(struct tracer
*trace
,
565 struct trace_array
*tr
);
566 extern int trace_selftest_startup_branch(struct tracer
*trace
,
567 struct trace_array
*tr
);
568 #endif /* CONFIG_FTRACE_STARTUP_TEST */
570 extern void *head_page(struct trace_array_cpu
*data
);
571 extern long ns2usecs(cycle_t nsec
);
573 trace_vprintk(unsigned long ip
, int depth
, const char *fmt
, va_list args
);
575 extern unsigned long trace_flags
;
577 /* Standard output formatting function used for function return traces */
578 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
579 extern enum print_line_t
print_graph_function(struct trace_iterator
*iter
);
581 #ifdef CONFIG_DYNAMIC_FTRACE
582 /* TODO: make this variable */
583 #define FTRACE_GRAPH_MAX_FUNCS 32
584 extern int ftrace_graph_count
;
585 extern unsigned long ftrace_graph_funcs
[FTRACE_GRAPH_MAX_FUNCS
];
587 static inline int ftrace_graph_addr(unsigned long addr
)
591 if (!ftrace_graph_count
|| test_tsk_trace_graph(current
))
594 for (i
= 0; i
< ftrace_graph_count
; i
++) {
595 if (addr
== ftrace_graph_funcs
[i
])
602 static inline int ftrace_trace_addr(unsigned long addr
)
606 static inline int ftrace_graph_addr(unsigned long addr
)
610 #endif /* CONFIG_DYNAMIC_FTRACE */
612 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
613 static inline enum print_line_t
614 print_graph_function(struct trace_iterator
*iter
)
616 return TRACE_TYPE_UNHANDLED
;
618 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
620 extern struct pid
*ftrace_pid_trace
;
622 static inline int ftrace_trace_task(struct task_struct
*task
)
624 if (!ftrace_pid_trace
)
627 return test_tsk_trace_trace(task
);
631 * trace_iterator_flags is an enumeration that defines bit
632 * positions into trace_flags that controls the output.
634 * NOTE: These bits must match the trace_options array in
637 enum trace_iterator_flags
{
638 TRACE_ITER_PRINT_PARENT
= 0x01,
639 TRACE_ITER_SYM_OFFSET
= 0x02,
640 TRACE_ITER_SYM_ADDR
= 0x04,
641 TRACE_ITER_VERBOSE
= 0x08,
642 TRACE_ITER_RAW
= 0x10,
643 TRACE_ITER_HEX
= 0x20,
644 TRACE_ITER_BIN
= 0x40,
645 TRACE_ITER_BLOCK
= 0x80,
646 TRACE_ITER_STACKTRACE
= 0x100,
647 TRACE_ITER_SCHED_TREE
= 0x200,
648 TRACE_ITER_PRINTK
= 0x400,
649 TRACE_ITER_PREEMPTONLY
= 0x800,
650 TRACE_ITER_BRANCH
= 0x1000,
651 TRACE_ITER_ANNOTATE
= 0x2000,
652 TRACE_ITER_USERSTACKTRACE
= 0x4000,
653 TRACE_ITER_SYM_USEROBJ
= 0x8000,
654 TRACE_ITER_PRINTK_MSGONLY
= 0x10000,
655 TRACE_ITER_CONTEXT_INFO
= 0x20000, /* Print pid/cpu/time */
656 TRACE_ITER_LATENCY_FMT
= 0x40000,
660 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
661 * control the output of kernel symbols.
663 #define TRACE_ITER_SYM_MASK \
664 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
666 extern struct tracer nop_trace
;
669 * ftrace_preempt_disable - disable preemption scheduler safe
671 * When tracing can happen inside the scheduler, there exists
672 * cases that the tracing might happen before the need_resched
673 * flag is checked. If this happens and the tracer calls
674 * preempt_enable (after a disable), a schedule might take place
675 * causing an infinite recursion.
677 * To prevent this, we read the need_resched flag before
678 * disabling preemption. When we want to enable preemption we
679 * check the flag, if it is set, then we call preempt_enable_no_resched.
680 * Otherwise, we call preempt_enable.
682 * The rational for doing the above is that if need_resched is set
683 * and we have yet to reschedule, we are either in an atomic location
684 * (where we do not need to check for scheduling) or we are inside
685 * the scheduler and do not want to resched.
687 static inline int ftrace_preempt_disable(void)
691 resched
= need_resched();
692 preempt_disable_notrace();
698 * ftrace_preempt_enable - enable preemption scheduler safe
699 * @resched: the return value from ftrace_preempt_disable
701 * This is a scheduler safe way to enable preemption and not miss
702 * any preemption checks. The disabled saved the state of preemption.
703 * If resched is set, then we are either inside an atomic or
704 * are inside the scheduler (we would have already scheduled
705 * otherwise). In this case, we do not want to call normal
706 * preempt_enable, but preempt_enable_no_resched instead.
708 static inline void ftrace_preempt_enable(int resched
)
711 preempt_enable_no_resched_notrace();
713 preempt_enable_notrace();
716 #ifdef CONFIG_BRANCH_TRACER
717 extern int enable_branch_tracing(struct trace_array
*tr
);
718 extern void disable_branch_tracing(void);
719 static inline int trace_branch_enable(struct trace_array
*tr
)
721 if (trace_flags
& TRACE_ITER_BRANCH
)
722 return enable_branch_tracing(tr
);
725 static inline void trace_branch_disable(void)
727 /* due to races, always disable */
728 disable_branch_tracing();
731 static inline int trace_branch_enable(struct trace_array
*tr
)
735 static inline void trace_branch_disable(void)
738 #endif /* CONFIG_BRANCH_TRACER */
740 /* trace event type bit fields, not numeric */
742 TRACE_EVENT_TYPE_PRINTF
= 1,
743 TRACE_EVENT_TYPE_RAW
= 2,
746 struct ftrace_event_call
{
751 int (*regfunc
)(void);
752 void (*unregfunc
)(void);
754 int (*raw_init
)(void);
755 int (*show_format
)(struct trace_seq
*s
);
758 void event_trace_printk(unsigned long ip
, const char *fmt
, ...);
759 extern struct ftrace_event_call __start_ftrace_events
[];
760 extern struct ftrace_event_call __stop_ftrace_events
[];
762 #endif /* _LINUX_KERNEL_TRACE_H */