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,
44 * The trace entry - the most basic unit of tracing. This is what
45 * is printed in the end as a single line in the trace output, such as:
47 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
52 unsigned char preempt_count
;
58 * Function trace entry - function address and parent function addres:
61 struct trace_entry ent
;
63 unsigned long parent_ip
;
66 /* Function call entry */
67 struct ftrace_graph_ent_entry
{
68 struct trace_entry ent
;
69 struct ftrace_graph_ent graph_ent
;
72 /* Function return entry */
73 struct ftrace_graph_ret_entry
{
74 struct trace_entry ent
;
75 struct ftrace_graph_ret ret
;
77 extern struct tracer boot_tracer
;
80 * Context switch trace entry - which task (and prio) we switched from/to:
82 struct ctx_switch_entry
{
83 struct trace_entry ent
;
84 unsigned int prev_pid
;
85 unsigned char prev_prio
;
86 unsigned char prev_state
;
87 unsigned int next_pid
;
88 unsigned char next_prio
;
89 unsigned char next_state
;
90 unsigned int next_cpu
;
94 * Special (free-form) trace entry:
96 struct special_entry
{
97 struct trace_entry ent
;
107 #define FTRACE_STACK_ENTRIES 8
110 struct trace_entry ent
;
111 unsigned long caller
[FTRACE_STACK_ENTRIES
];
114 struct userstack_entry
{
115 struct trace_entry ent
;
116 unsigned long caller
[FTRACE_STACK_ENTRIES
];
120 * trace_printk entry:
123 struct trace_entry ent
;
130 #define TRACE_OLD_SIZE 88
132 struct trace_field_cont
{
134 /* Temporary till we get rid of this completely */
135 char buf
[TRACE_OLD_SIZE
- 1];
138 struct trace_mmiotrace_rw
{
139 struct trace_entry ent
;
140 struct mmiotrace_rw rw
;
143 struct trace_mmiotrace_map
{
144 struct trace_entry ent
;
145 struct mmiotrace_map map
;
148 struct trace_boot_call
{
149 struct trace_entry ent
;
150 struct boot_trace_call boot_call
;
153 struct trace_boot_ret
{
154 struct trace_entry ent
;
155 struct boot_trace_ret boot_ret
;
158 #define TRACE_FUNC_SIZE 30
159 #define TRACE_FILE_SIZE 20
160 struct trace_branch
{
161 struct trace_entry ent
;
163 char func
[TRACE_FUNC_SIZE
+1];
164 char file
[TRACE_FILE_SIZE
+1];
168 struct hw_branch_entry
{
169 struct trace_entry ent
;
175 struct trace_entry ent
;
176 struct power_trace state_data
;
179 struct kmemtrace_alloc_entry
{
180 struct trace_entry ent
;
181 enum kmemtrace_type_id type_id
;
182 unsigned long call_site
;
190 struct kmemtrace_free_entry
{
191 struct trace_entry ent
;
192 enum kmemtrace_type_id type_id
;
193 unsigned long call_site
;
197 struct syscall_trace_enter
{
198 struct trace_entry ent
;
200 unsigned long args
[];
203 struct syscall_trace_exit
{
204 struct trace_entry ent
;
211 * trace_flag_type is an enumeration that holds different
212 * states when a trace occurs. These are:
213 * IRQS_OFF - interrupts were disabled
214 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
215 * NEED_RESCED - reschedule is requested
216 * HARDIRQ - inside an interrupt handler
217 * SOFTIRQ - inside a softirq handler
219 enum trace_flag_type
{
220 TRACE_FLAG_IRQS_OFF
= 0x01,
221 TRACE_FLAG_IRQS_NOSUPPORT
= 0x02,
222 TRACE_FLAG_NEED_RESCHED
= 0x04,
223 TRACE_FLAG_HARDIRQ
= 0x08,
224 TRACE_FLAG_SOFTIRQ
= 0x10,
227 #define TRACE_BUF_SIZE 1024
230 * The CPU trace array - it consists of thousands of trace entries
231 * plus some other descriptor data: (for example which task started
234 struct trace_array_cpu
{
236 void *buffer_page
; /* ring buffer spare */
238 /* these fields get copied into max-trace: */
239 unsigned long trace_idx
;
240 unsigned long overrun
;
241 unsigned long saved_latency
;
242 unsigned long critical_start
;
243 unsigned long critical_end
;
244 unsigned long critical_sequence
;
246 unsigned long policy
;
247 unsigned long rt_priority
;
248 cycle_t preempt_timestamp
;
251 char comm
[TASK_COMM_LEN
];
254 struct trace_iterator
;
257 * The trace array - an array of per-CPU trace arrays. This is the
258 * highest level data structure that individual tracers deal with.
259 * They have on/off state as well:
262 struct ring_buffer
*buffer
;
263 unsigned long entries
;
266 struct task_struct
*waiter
;
267 struct trace_array_cpu
*data
[NR_CPUS
];
270 #define FTRACE_CMP_TYPE(var, type) \
271 __builtin_types_compatible_p(typeof(var), type *)
274 #define IF_ASSIGN(var, entry, etype, id) \
275 if (FTRACE_CMP_TYPE(var, etype)) { \
276 var = (typeof(var))(entry); \
277 WARN_ON(id && (entry)->type != id); \
281 /* Will cause compile errors if type is not found. */
282 extern void __ftrace_bad_type(void);
285 * The trace_assign_type is a verifier that the entry type is
286 * the same as the type being assigned. To add new types simply
287 * add a line with the following format:
289 * IF_ASSIGN(var, ent, type, id);
291 * Where "type" is the trace type that includes the trace_entry
292 * as the "ent" item. And "id" is the trace identifier that is
293 * used in the trace_type enum.
295 * If the type can have more than one id, then use zero.
297 #define trace_assign_type(var, ent) \
299 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
300 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
301 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
302 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
303 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
304 IF_ASSIGN(var, ent, struct special_entry, 0); \
305 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
307 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
309 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
310 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
311 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
312 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
314 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
316 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
317 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
318 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
320 IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
322 IF_ASSIGN(var, ent, struct syscall_trace_enter, \
323 TRACE_SYSCALL_ENTER); \
324 IF_ASSIGN(var, ent, struct syscall_trace_exit, \
325 TRACE_SYSCALL_EXIT); \
326 __ftrace_bad_type(); \
329 /* Return values for print_line callback */
331 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
332 TRACE_TYPE_HANDLED
= 1,
333 TRACE_TYPE_UNHANDLED
= 2, /* Relay to other output functions */
334 TRACE_TYPE_NO_CONSUME
= 3 /* Handled but ask to not consume */
339 * An option specific to a tracer. This is a boolean value.
340 * The bit is the bit index that sets its value on the
341 * flags value in struct tracer_flags.
344 const char *name
; /* Will appear on the trace_options file */
345 u32 bit
; /* Mask assigned in val field in tracer_flags */
349 * The set of specific options for a tracer. Your tracer
350 * have to set the initial value of the flags val.
352 struct tracer_flags
{
354 struct tracer_opt
*opts
;
357 /* Makes more easy to define a tracer opt */
358 #define TRACER_OPT(s, b) .name = #s, .bit = b
362 * struct tracer - a specific tracer and its callbacks to interact with debugfs
363 * @name: the name chosen to select it on the available_tracers file
364 * @init: called when one switches to this tracer (echo name > current_tracer)
365 * @reset: called when one switches to another tracer
366 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
367 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
368 * @open: called when the trace file is opened
369 * @pipe_open: called when the trace_pipe file is opened
370 * @wait_pipe: override how the user waits for traces on trace_pipe
371 * @close: called when the trace file is released
372 * @read: override the default read callback on trace_pipe
373 * @splice_read: override the default splice_read callback on trace_pipe
374 * @selftest: selftest to run on boot (see trace_selftest.c)
375 * @print_headers: override the first lines that describe your columns
376 * @print_line: callback that prints a trace
377 * @set_flag: signals one of your private flags changed (trace_options file)
378 * @flags: your private flags
382 int (*init
)(struct trace_array
*tr
);
383 void (*reset
)(struct trace_array
*tr
);
384 void (*start
)(struct trace_array
*tr
);
385 void (*stop
)(struct trace_array
*tr
);
386 void (*open
)(struct trace_iterator
*iter
);
387 void (*pipe_open
)(struct trace_iterator
*iter
);
388 void (*wait_pipe
)(struct trace_iterator
*iter
);
389 void (*close
)(struct trace_iterator
*iter
);
390 ssize_t (*read
)(struct trace_iterator
*iter
,
391 struct file
*filp
, char __user
*ubuf
,
392 size_t cnt
, loff_t
*ppos
);
393 ssize_t (*splice_read
)(struct trace_iterator
*iter
,
396 struct pipe_inode_info
*pipe
,
399 #ifdef CONFIG_FTRACE_STARTUP_TEST
400 int (*selftest
)(struct tracer
*trace
,
401 struct trace_array
*tr
);
403 void (*print_header
)(struct seq_file
*m
);
404 enum print_line_t (*print_line
)(struct trace_iterator
*iter
);
405 /* If you handled the flag setting, return 0 */
406 int (*set_flag
)(u32 old_flags
, u32 bit
, int set
);
409 struct tracer_flags
*flags
;
410 struct tracer_stat
*stats
;
414 unsigned char buffer
[PAGE_SIZE
];
416 unsigned int readpos
;
420 trace_seq_init(struct trace_seq
*s
)
427 #define TRACE_PIPE_ALL_CPU -1
430 * Trace iterator - used by printout routines who present trace
431 * results to users and which routines might sleep, etc:
433 struct trace_iterator
{
434 struct trace_array
*tr
;
435 struct tracer
*trace
;
439 struct ring_buffer_iter
*buffer_iter
[NR_CPUS
];
441 /* The below is zeroed out in pipe_read */
442 struct trace_seq seq
;
443 struct trace_entry
*ent
;
447 unsigned long iter_flags
;
451 cpumask_var_t started
;
454 int tracer_init(struct tracer
*t
, struct trace_array
*tr
);
455 int tracing_is_enabled(void);
456 void trace_wake_up(void);
457 void tracing_reset(struct trace_array
*tr
, int cpu
);
458 void tracing_reset_online_cpus(struct trace_array
*tr
);
459 int tracing_open_generic(struct inode
*inode
, struct file
*filp
);
460 struct dentry
*tracing_init_dentry(void);
461 void init_tracer_sysprof_debugfs(struct dentry
*d_tracer
);
463 struct ring_buffer_event
;
465 struct ring_buffer_event
*trace_buffer_lock_reserve(struct trace_array
*tr
,
470 void trace_buffer_unlock_commit(struct trace_array
*tr
,
471 struct ring_buffer_event
*event
,
472 unsigned long flags
, int pc
);
474 struct ring_buffer_event
*
475 trace_current_buffer_lock_reserve(unsigned char type
, unsigned long len
,
476 unsigned long flags
, int pc
);
477 void trace_current_buffer_unlock_commit(struct ring_buffer_event
*event
,
478 unsigned long flags
, int pc
);
480 struct trace_entry
*tracing_get_trace_entry(struct trace_array
*tr
,
481 struct trace_array_cpu
*data
);
483 struct trace_entry
*trace_find_next_entry(struct trace_iterator
*iter
,
484 int *ent_cpu
, u64
*ent_ts
);
486 void tracing_generic_entry_update(struct trace_entry
*entry
,
490 void default_wait_pipe(struct trace_iterator
*iter
);
491 void poll_wait_pipe(struct trace_iterator
*iter
);
493 void ftrace(struct trace_array
*tr
,
494 struct trace_array_cpu
*data
,
496 unsigned long parent_ip
,
497 unsigned long flags
, int pc
);
498 void tracing_sched_switch_trace(struct trace_array
*tr
,
499 struct task_struct
*prev
,
500 struct task_struct
*next
,
501 unsigned long flags
, int pc
);
502 void tracing_record_cmdline(struct task_struct
*tsk
);
504 void tracing_sched_wakeup_trace(struct trace_array
*tr
,
505 struct task_struct
*wakee
,
506 struct task_struct
*cur
,
507 unsigned long flags
, int pc
);
508 void trace_special(struct trace_array
*tr
,
509 struct trace_array_cpu
*data
,
512 unsigned long arg3
, int pc
);
513 void trace_function(struct trace_array
*tr
,
515 unsigned long parent_ip
,
516 unsigned long flags
, int pc
);
518 void trace_graph_return(struct ftrace_graph_ret
*trace
);
519 int trace_graph_entry(struct ftrace_graph_ent
*trace
);
521 void tracing_start_cmdline_record(void);
522 void tracing_stop_cmdline_record(void);
523 void tracing_sched_switch_assign_trace(struct trace_array
*tr
);
524 void tracing_stop_sched_switch_record(void);
525 void tracing_start_sched_switch_record(void);
526 int register_tracer(struct tracer
*type
);
527 void unregister_tracer(struct tracer
*type
);
529 extern unsigned long nsecs_to_usecs(unsigned long nsecs
);
531 extern unsigned long tracing_max_latency
;
532 extern unsigned long tracing_thresh
;
534 void update_max_tr(struct trace_array
*tr
, struct task_struct
*tsk
, int cpu
);
535 void update_max_tr_single(struct trace_array
*tr
,
536 struct task_struct
*tsk
, int cpu
);
538 void __trace_stack(struct trace_array
*tr
,
542 extern cycle_t
ftrace_now(int cpu
);
544 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
546 (*tracer_switch_func_t
)(void *private,
548 struct task_struct
*prev
,
549 struct task_struct
*next
);
551 struct tracer_switch_ops
{
552 tracer_switch_func_t func
;
554 struct tracer_switch_ops
*next
;
556 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
558 extern char *trace_find_cmdline(int pid
);
560 #ifdef CONFIG_DYNAMIC_FTRACE
561 extern unsigned long ftrace_update_tot_cnt
;
562 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
563 extern int DYN_FTRACE_TEST_NAME(void);
566 #ifdef CONFIG_FTRACE_STARTUP_TEST
567 extern int trace_selftest_startup_function(struct tracer
*trace
,
568 struct trace_array
*tr
);
569 extern int trace_selftest_startup_function_graph(struct tracer
*trace
,
570 struct trace_array
*tr
);
571 extern int trace_selftest_startup_irqsoff(struct tracer
*trace
,
572 struct trace_array
*tr
);
573 extern int trace_selftest_startup_preemptoff(struct tracer
*trace
,
574 struct trace_array
*tr
);
575 extern int trace_selftest_startup_preemptirqsoff(struct tracer
*trace
,
576 struct trace_array
*tr
);
577 extern int trace_selftest_startup_wakeup(struct tracer
*trace
,
578 struct trace_array
*tr
);
579 extern int trace_selftest_startup_nop(struct tracer
*trace
,
580 struct trace_array
*tr
);
581 extern int trace_selftest_startup_sched_switch(struct tracer
*trace
,
582 struct trace_array
*tr
);
583 extern int trace_selftest_startup_sysprof(struct tracer
*trace
,
584 struct trace_array
*tr
);
585 extern int trace_selftest_startup_branch(struct tracer
*trace
,
586 struct trace_array
*tr
);
587 #endif /* CONFIG_FTRACE_STARTUP_TEST */
589 extern void *head_page(struct trace_array_cpu
*data
);
590 extern long ns2usecs(cycle_t nsec
);
592 trace_vprintk(unsigned long ip
, int depth
, const char *fmt
, va_list args
);
594 extern unsigned long trace_flags
;
596 /* Standard output formatting function used for function return traces */
597 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
598 extern enum print_line_t
print_graph_function(struct trace_iterator
*iter
);
600 #ifdef CONFIG_DYNAMIC_FTRACE
601 /* TODO: make this variable */
602 #define FTRACE_GRAPH_MAX_FUNCS 32
603 extern int ftrace_graph_count
;
604 extern unsigned long ftrace_graph_funcs
[FTRACE_GRAPH_MAX_FUNCS
];
606 static inline int ftrace_graph_addr(unsigned long addr
)
610 if (!ftrace_graph_count
|| test_tsk_trace_graph(current
))
613 for (i
= 0; i
< ftrace_graph_count
; i
++) {
614 if (addr
== ftrace_graph_funcs
[i
])
621 static inline int ftrace_trace_addr(unsigned long addr
)
625 static inline int ftrace_graph_addr(unsigned long addr
)
629 #endif /* CONFIG_DYNAMIC_FTRACE */
631 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
632 static inline enum print_line_t
633 print_graph_function(struct trace_iterator
*iter
)
635 return TRACE_TYPE_UNHANDLED
;
637 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
639 extern struct pid
*ftrace_pid_trace
;
641 static inline int ftrace_trace_task(struct task_struct
*task
)
643 if (!ftrace_pid_trace
)
646 return test_tsk_trace_trace(task
);
650 * trace_iterator_flags is an enumeration that defines bit
651 * positions into trace_flags that controls the output.
653 * NOTE: These bits must match the trace_options array in
656 enum trace_iterator_flags
{
657 TRACE_ITER_PRINT_PARENT
= 0x01,
658 TRACE_ITER_SYM_OFFSET
= 0x02,
659 TRACE_ITER_SYM_ADDR
= 0x04,
660 TRACE_ITER_VERBOSE
= 0x08,
661 TRACE_ITER_RAW
= 0x10,
662 TRACE_ITER_HEX
= 0x20,
663 TRACE_ITER_BIN
= 0x40,
664 TRACE_ITER_BLOCK
= 0x80,
665 TRACE_ITER_STACKTRACE
= 0x100,
666 TRACE_ITER_SCHED_TREE
= 0x200,
667 TRACE_ITER_PRINTK
= 0x400,
668 TRACE_ITER_PREEMPTONLY
= 0x800,
669 TRACE_ITER_BRANCH
= 0x1000,
670 TRACE_ITER_ANNOTATE
= 0x2000,
671 TRACE_ITER_USERSTACKTRACE
= 0x4000,
672 TRACE_ITER_SYM_USEROBJ
= 0x8000,
673 TRACE_ITER_PRINTK_MSGONLY
= 0x10000,
674 TRACE_ITER_CONTEXT_INFO
= 0x20000, /* Print pid/cpu/time */
675 TRACE_ITER_LATENCY_FMT
= 0x40000,
679 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
680 * control the output of kernel symbols.
682 #define TRACE_ITER_SYM_MASK \
683 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
685 extern struct tracer nop_trace
;
688 * ftrace_preempt_disable - disable preemption scheduler safe
690 * When tracing can happen inside the scheduler, there exists
691 * cases that the tracing might happen before the need_resched
692 * flag is checked. If this happens and the tracer calls
693 * preempt_enable (after a disable), a schedule might take place
694 * causing an infinite recursion.
696 * To prevent this, we read the need_resched flag before
697 * disabling preemption. When we want to enable preemption we
698 * check the flag, if it is set, then we call preempt_enable_no_resched.
699 * Otherwise, we call preempt_enable.
701 * The rational for doing the above is that if need_resched is set
702 * and we have yet to reschedule, we are either in an atomic location
703 * (where we do not need to check for scheduling) or we are inside
704 * the scheduler and do not want to resched.
706 static inline int ftrace_preempt_disable(void)
710 resched
= need_resched();
711 preempt_disable_notrace();
717 * ftrace_preempt_enable - enable preemption scheduler safe
718 * @resched: the return value from ftrace_preempt_disable
720 * This is a scheduler safe way to enable preemption and not miss
721 * any preemption checks. The disabled saved the state of preemption.
722 * If resched is set, then we are either inside an atomic or
723 * are inside the scheduler (we would have already scheduled
724 * otherwise). In this case, we do not want to call normal
725 * preempt_enable, but preempt_enable_no_resched instead.
727 static inline void ftrace_preempt_enable(int resched
)
730 preempt_enable_no_resched_notrace();
732 preempt_enable_notrace();
735 #ifdef CONFIG_BRANCH_TRACER
736 extern int enable_branch_tracing(struct trace_array
*tr
);
737 extern void disable_branch_tracing(void);
738 static inline int trace_branch_enable(struct trace_array
*tr
)
740 if (trace_flags
& TRACE_ITER_BRANCH
)
741 return enable_branch_tracing(tr
);
744 static inline void trace_branch_disable(void)
746 /* due to races, always disable */
747 disable_branch_tracing();
750 static inline int trace_branch_enable(struct trace_array
*tr
)
754 static inline void trace_branch_disable(void)
757 #endif /* CONFIG_BRANCH_TRACER */
759 /* trace event type bit fields, not numeric */
761 TRACE_EVENT_TYPE_PRINTF
= 1,
762 TRACE_EVENT_TYPE_RAW
= 2,
765 struct ftrace_event_call
{
770 int (*regfunc
)(void);
771 void (*unregfunc
)(void);
773 int (*raw_init
)(void);
774 int (*show_format
)(struct trace_seq
*s
);
777 void event_trace_printk(unsigned long ip
, const char *fmt
, ...);
778 extern struct ftrace_event_call __start_ftrace_events
[];
779 extern struct ftrace_event_call __stop_ftrace_events
[];
781 #endif /* _LINUX_KERNEL_TRACE_H */