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>
14 __TRACE_FIRST_TYPE
= 0,
37 * The trace entry - the most basic unit of tracing. This is what
38 * is printed in the end as a single line in the trace output, such as:
40 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
46 unsigned char preempt_count
;
52 * Function trace entry - function address and parent function addres:
55 struct trace_entry ent
;
57 unsigned long parent_ip
;
60 /* Function call entry */
61 struct ftrace_graph_ent_entry
{
62 struct trace_entry ent
;
63 struct ftrace_graph_ent graph_ent
;
66 /* Function return entry */
67 struct ftrace_graph_ret_entry
{
68 struct trace_entry ent
;
69 struct ftrace_graph_ret ret
;
71 extern struct tracer boot_tracer
;
74 * Context switch trace entry - which task (and prio) we switched from/to:
76 struct ctx_switch_entry
{
77 struct trace_entry ent
;
78 unsigned int prev_pid
;
79 unsigned char prev_prio
;
80 unsigned char prev_state
;
81 unsigned int next_pid
;
82 unsigned char next_prio
;
83 unsigned char next_state
;
84 unsigned int next_cpu
;
88 * Special (free-form) trace entry:
90 struct special_entry
{
91 struct trace_entry ent
;
101 #define FTRACE_STACK_ENTRIES 8
104 struct trace_entry ent
;
105 unsigned long caller
[FTRACE_STACK_ENTRIES
];
108 struct userstack_entry
{
109 struct trace_entry ent
;
110 unsigned long caller
[FTRACE_STACK_ENTRIES
];
114 * ftrace_printk entry:
117 struct trace_entry ent
;
123 #define TRACE_OLD_SIZE 88
125 struct trace_field_cont
{
127 /* Temporary till we get rid of this completely */
128 char buf
[TRACE_OLD_SIZE
- 1];
131 struct trace_mmiotrace_rw
{
132 struct trace_entry ent
;
133 struct mmiotrace_rw rw
;
136 struct trace_mmiotrace_map
{
137 struct trace_entry ent
;
138 struct mmiotrace_map map
;
141 struct trace_boot_call
{
142 struct trace_entry ent
;
143 struct boot_trace_call boot_call
;
146 struct trace_boot_ret
{
147 struct trace_entry ent
;
148 struct boot_trace_ret boot_ret
;
151 #define TRACE_FUNC_SIZE 30
152 #define TRACE_FILE_SIZE 20
153 struct trace_branch
{
154 struct trace_entry ent
;
156 char func
[TRACE_FUNC_SIZE
+1];
157 char file
[TRACE_FILE_SIZE
+1];
161 struct hw_branch_entry
{
162 struct trace_entry ent
;
168 struct trace_entry ent
;
169 struct power_trace state_data
;
173 * trace_flag_type is an enumeration that holds different
174 * states when a trace occurs. These are:
175 * IRQS_OFF - interrupts were disabled
176 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
177 * NEED_RESCED - reschedule is requested
178 * HARDIRQ - inside an interrupt handler
179 * SOFTIRQ - inside a softirq handler
181 enum trace_flag_type
{
182 TRACE_FLAG_IRQS_OFF
= 0x01,
183 TRACE_FLAG_IRQS_NOSUPPORT
= 0x02,
184 TRACE_FLAG_NEED_RESCHED
= 0x04,
185 TRACE_FLAG_HARDIRQ
= 0x08,
186 TRACE_FLAG_SOFTIRQ
= 0x10,
189 #define TRACE_BUF_SIZE 1024
192 * The CPU trace array - it consists of thousands of trace entries
193 * plus some other descriptor data: (for example which task started
196 struct trace_array_cpu
{
199 /* these fields get copied into max-trace: */
200 unsigned long trace_idx
;
201 unsigned long overrun
;
202 unsigned long saved_latency
;
203 unsigned long critical_start
;
204 unsigned long critical_end
;
205 unsigned long critical_sequence
;
207 unsigned long policy
;
208 unsigned long rt_priority
;
209 cycle_t preempt_timestamp
;
212 char comm
[TASK_COMM_LEN
];
215 struct trace_iterator
;
218 * The trace array - an array of per-CPU trace arrays. This is the
219 * highest level data structure that individual tracers deal with.
220 * They have on/off state as well:
223 struct ring_buffer
*buffer
;
224 unsigned long entries
;
227 struct task_struct
*waiter
;
228 struct trace_array_cpu
*data
[NR_CPUS
];
231 #define FTRACE_CMP_TYPE(var, type) \
232 __builtin_types_compatible_p(typeof(var), type *)
235 #define IF_ASSIGN(var, entry, etype, id) \
236 if (FTRACE_CMP_TYPE(var, etype)) { \
237 var = (typeof(var))(entry); \
238 WARN_ON(id && (entry)->type != id); \
242 /* Will cause compile errors if type is not found. */
243 extern void __ftrace_bad_type(void);
246 * The trace_assign_type is a verifier that the entry type is
247 * the same as the type being assigned. To add new types simply
248 * add a line with the following format:
250 * IF_ASSIGN(var, ent, type, id);
252 * Where "type" is the trace type that includes the trace_entry
253 * as the "ent" item. And "id" is the trace identifier that is
254 * used in the trace_type enum.
256 * If the type can have more than one id, then use zero.
258 #define trace_assign_type(var, ent) \
260 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
261 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
262 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
263 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
264 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
265 IF_ASSIGN(var, ent, struct special_entry, 0); \
266 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
268 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
270 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
271 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
272 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
273 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
275 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
277 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
278 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
279 __ftrace_bad_type(); \
282 /* Return values for print_line callback */
284 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
285 TRACE_TYPE_HANDLED
= 1,
286 TRACE_TYPE_UNHANDLED
= 2 /* Relay to other output functions */
291 * An option specific to a tracer. This is a boolean value.
292 * The bit is the bit index that sets its value on the
293 * flags value in struct tracer_flags.
296 const char *name
; /* Will appear on the trace_options file */
297 u32 bit
; /* Mask assigned in val field in tracer_flags */
301 * The set of specific options for a tracer. Your tracer
302 * have to set the initial value of the flags val.
304 struct tracer_flags
{
306 struct tracer_opt
*opts
;
309 /* Makes more easy to define a tracer opt */
310 #define TRACER_OPT(s, b) .name = #s, .bit = b
313 * A specific tracer, represented by methods that operate on a trace array:
317 /* Your tracer should raise a warning if init fails */
318 int (*init
)(struct trace_array
*tr
);
319 void (*reset
)(struct trace_array
*tr
);
320 void (*start
)(struct trace_array
*tr
);
321 void (*stop
)(struct trace_array
*tr
);
322 void (*open
)(struct trace_iterator
*iter
);
323 void (*pipe_open
)(struct trace_iterator
*iter
);
324 void (*close
)(struct trace_iterator
*iter
);
325 ssize_t (*read
)(struct trace_iterator
*iter
,
326 struct file
*filp
, char __user
*ubuf
,
327 size_t cnt
, loff_t
*ppos
);
328 #ifdef CONFIG_FTRACE_STARTUP_TEST
329 int (*selftest
)(struct tracer
*trace
,
330 struct trace_array
*tr
);
332 void (*print_header
)(struct seq_file
*m
);
333 enum print_line_t (*print_line
)(struct trace_iterator
*iter
);
334 /* If you handled the flag setting, return 0 */
335 int (*set_flag
)(u32 old_flags
, u32 bit
, int set
);
338 struct tracer_flags
*flags
;
341 * If you change one of the following on tracing runtime, recall
345 /* Iteration over statistic entries */
346 void *(*stat_start
)(void);
347 void *(*stat_next
)(void *prev
, int idx
);
348 /* Compare two entries for sorting (optional) for stats */
349 int (*stat_cmp
)(void *p1
, void *p2
);
350 /* Print a stat entry */
351 int (*stat_show
)(struct seq_file
*s
, void *p
);
352 /* Print the headers of your stat entries */
353 int (*stat_headers
)(struct seq_file
*s
);
357 unsigned char buffer
[PAGE_SIZE
];
359 unsigned int readpos
;
363 * Trace iterator - used by printout routines who present trace
364 * results to users and which routines might sleep, etc:
366 struct trace_iterator
{
367 struct trace_array
*tr
;
368 struct tracer
*trace
;
370 struct ring_buffer_iter
*buffer_iter
[NR_CPUS
];
372 /* The below is zeroed out in pipe_read */
373 struct trace_seq seq
;
374 struct trace_entry
*ent
;
378 unsigned long iter_flags
;
385 int tracing_is_enabled(void);
386 void trace_wake_up(void);
387 void tracing_reset(struct trace_array
*tr
, int cpu
);
388 void tracing_reset_online_cpus(struct trace_array
*tr
);
389 int tracing_open_generic(struct inode
*inode
, struct file
*filp
);
390 struct dentry
*tracing_init_dentry(void);
391 void init_tracer_sysprof_debugfs(struct dentry
*d_tracer
);
393 struct trace_entry
*tracing_get_trace_entry(struct trace_array
*tr
,
394 struct trace_array_cpu
*data
);
395 void tracing_generic_entry_update(struct trace_entry
*entry
,
399 void ftrace(struct trace_array
*tr
,
400 struct trace_array_cpu
*data
,
402 unsigned long parent_ip
,
403 unsigned long flags
, int pc
);
404 void tracing_sched_switch_trace(struct trace_array
*tr
,
405 struct trace_array_cpu
*data
,
406 struct task_struct
*prev
,
407 struct task_struct
*next
,
408 unsigned long flags
, int pc
);
409 void tracing_record_cmdline(struct task_struct
*tsk
);
411 void tracing_sched_wakeup_trace(struct trace_array
*tr
,
412 struct trace_array_cpu
*data
,
413 struct task_struct
*wakee
,
414 struct task_struct
*cur
,
415 unsigned long flags
, int pc
);
416 void trace_special(struct trace_array
*tr
,
417 struct trace_array_cpu
*data
,
420 unsigned long arg3
, int pc
);
421 void trace_function(struct trace_array
*tr
,
422 struct trace_array_cpu
*data
,
424 unsigned long parent_ip
,
425 unsigned long flags
, int pc
);
427 void trace_graph_return(struct ftrace_graph_ret
*trace
);
428 int trace_graph_entry(struct ftrace_graph_ent
*trace
);
429 void trace_hw_branch(struct trace_array
*tr
, u64 from
, u64 to
);
431 void tracing_start_cmdline_record(void);
432 void tracing_stop_cmdline_record(void);
433 void tracing_sched_switch_assign_trace(struct trace_array
*tr
);
434 void tracing_stop_sched_switch_record(void);
435 void tracing_start_sched_switch_record(void);
436 int register_tracer(struct tracer
*type
);
437 void unregister_tracer(struct tracer
*type
);
439 void init_tracer_stat(struct tracer
*trace
);
441 extern unsigned long nsecs_to_usecs(unsigned long nsecs
);
443 extern unsigned long tracing_max_latency
;
444 extern unsigned long tracing_thresh
;
446 void update_max_tr(struct trace_array
*tr
, struct task_struct
*tsk
, int cpu
);
447 void update_max_tr_single(struct trace_array
*tr
,
448 struct task_struct
*tsk
, int cpu
);
450 extern cycle_t
ftrace_now(int cpu
);
452 #ifdef CONFIG_FUNCTION_TRACER
453 void tracing_start_function_trace(void);
454 void tracing_stop_function_trace(void);
456 # define tracing_start_function_trace() do { } while (0)
457 # define tracing_stop_function_trace() do { } while (0)
460 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
462 (*tracer_switch_func_t
)(void *private,
464 struct task_struct
*prev
,
465 struct task_struct
*next
);
467 struct tracer_switch_ops
{
468 tracer_switch_func_t func
;
470 struct tracer_switch_ops
*next
;
472 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
474 extern char *trace_find_cmdline(int pid
);
476 #ifdef CONFIG_DYNAMIC_FTRACE
477 extern unsigned long ftrace_update_tot_cnt
;
478 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
479 extern int DYN_FTRACE_TEST_NAME(void);
482 #ifdef CONFIG_FTRACE_STARTUP_TEST
483 extern int trace_selftest_startup_function(struct tracer
*trace
,
484 struct trace_array
*tr
);
485 extern int trace_selftest_startup_irqsoff(struct tracer
*trace
,
486 struct trace_array
*tr
);
487 extern int trace_selftest_startup_preemptoff(struct tracer
*trace
,
488 struct trace_array
*tr
);
489 extern int trace_selftest_startup_preemptirqsoff(struct tracer
*trace
,
490 struct trace_array
*tr
);
491 extern int trace_selftest_startup_wakeup(struct tracer
*trace
,
492 struct trace_array
*tr
);
493 extern int trace_selftest_startup_nop(struct tracer
*trace
,
494 struct trace_array
*tr
);
495 extern int trace_selftest_startup_sched_switch(struct tracer
*trace
,
496 struct trace_array
*tr
);
497 extern int trace_selftest_startup_sysprof(struct tracer
*trace
,
498 struct trace_array
*tr
);
499 extern int trace_selftest_startup_branch(struct tracer
*trace
,
500 struct trace_array
*tr
);
501 #endif /* CONFIG_FTRACE_STARTUP_TEST */
503 extern void *head_page(struct trace_array_cpu
*data
);
504 extern long ns2usecs(cycle_t nsec
);
506 trace_vprintk(unsigned long ip
, int depth
, const char *fmt
, va_list args
);
508 extern unsigned long trace_flags
;
510 /* Standard output formatting function used for function return traces */
511 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
512 extern enum print_line_t
print_graph_function(struct trace_iterator
*iter
);
514 #ifdef CONFIG_DYNAMIC_FTRACE
515 /* TODO: make this variable */
516 #define FTRACE_GRAPH_MAX_FUNCS 32
517 extern int ftrace_graph_count
;
518 extern unsigned long ftrace_graph_funcs
[FTRACE_GRAPH_MAX_FUNCS
];
520 static inline int ftrace_graph_addr(unsigned long addr
)
524 if (!ftrace_graph_count
|| test_tsk_trace_graph(current
))
527 for (i
= 0; i
< ftrace_graph_count
; i
++) {
528 if (addr
== ftrace_graph_funcs
[i
])
535 static inline int ftrace_trace_addr(unsigned long addr
)
539 static inline int ftrace_graph_addr(unsigned long addr
)
543 #endif /* CONFIG_DYNAMIC_FTRACE */
545 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
546 static inline enum print_line_t
547 print_graph_function(struct trace_iterator
*iter
)
549 return TRACE_TYPE_UNHANDLED
;
551 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
553 extern struct pid
*ftrace_pid_trace
;
555 static inline int ftrace_trace_task(struct task_struct
*task
)
557 if (!ftrace_pid_trace
)
560 return test_tsk_trace_trace(task
);
564 * trace_iterator_flags is an enumeration that defines bit
565 * positions into trace_flags that controls the output.
567 * NOTE: These bits must match the trace_options array in
570 enum trace_iterator_flags
{
571 TRACE_ITER_PRINT_PARENT
= 0x01,
572 TRACE_ITER_SYM_OFFSET
= 0x02,
573 TRACE_ITER_SYM_ADDR
= 0x04,
574 TRACE_ITER_VERBOSE
= 0x08,
575 TRACE_ITER_RAW
= 0x10,
576 TRACE_ITER_HEX
= 0x20,
577 TRACE_ITER_BIN
= 0x40,
578 TRACE_ITER_BLOCK
= 0x80,
579 TRACE_ITER_STACKTRACE
= 0x100,
580 TRACE_ITER_SCHED_TREE
= 0x200,
581 TRACE_ITER_PRINTK
= 0x400,
582 TRACE_ITER_PREEMPTONLY
= 0x800,
583 TRACE_ITER_BRANCH
= 0x1000,
584 TRACE_ITER_ANNOTATE
= 0x2000,
585 TRACE_ITER_USERSTACKTRACE
= 0x4000,
586 TRACE_ITER_SYM_USEROBJ
= 0x8000,
587 TRACE_ITER_PRINTK_MSGONLY
= 0x10000
591 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
592 * control the output of kernel symbols.
594 #define TRACE_ITER_SYM_MASK \
595 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
597 extern struct tracer nop_trace
;
600 * ftrace_preempt_disable - disable preemption scheduler safe
602 * When tracing can happen inside the scheduler, there exists
603 * cases that the tracing might happen before the need_resched
604 * flag is checked. If this happens and the tracer calls
605 * preempt_enable (after a disable), a schedule might take place
606 * causing an infinite recursion.
608 * To prevent this, we read the need_recshed flag before
609 * disabling preemption. When we want to enable preemption we
610 * check the flag, if it is set, then we call preempt_enable_no_resched.
611 * Otherwise, we call preempt_enable.
613 * The rational for doing the above is that if need resched is set
614 * and we have yet to reschedule, we are either in an atomic location
615 * (where we do not need to check for scheduling) or we are inside
616 * the scheduler and do not want to resched.
618 static inline int ftrace_preempt_disable(void)
622 resched
= need_resched();
623 preempt_disable_notrace();
629 * ftrace_preempt_enable - enable preemption scheduler safe
630 * @resched: the return value from ftrace_preempt_disable
632 * This is a scheduler safe way to enable preemption and not miss
633 * any preemption checks. The disabled saved the state of preemption.
634 * If resched is set, then we were either inside an atomic or
635 * are inside the scheduler (we would have already scheduled
636 * otherwise). In this case, we do not want to call normal
637 * preempt_enable, but preempt_enable_no_resched instead.
639 static inline void ftrace_preempt_enable(int resched
)
642 preempt_enable_no_resched_notrace();
644 preempt_enable_notrace();
647 #ifdef CONFIG_BRANCH_TRACER
648 extern int enable_branch_tracing(struct trace_array
*tr
);
649 extern void disable_branch_tracing(void);
650 static inline int trace_branch_enable(struct trace_array
*tr
)
652 if (trace_flags
& TRACE_ITER_BRANCH
)
653 return enable_branch_tracing(tr
);
656 static inline void trace_branch_disable(void)
658 /* due to races, always disable */
659 disable_branch_tracing();
662 static inline int trace_branch_enable(struct trace_array
*tr
)
666 static inline void trace_branch_disable(void)
669 #endif /* CONFIG_BRANCH_TRACER */
671 #endif /* _LINUX_KERNEL_TRACE_H */