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,
38 * The trace entry - the most basic unit of tracing. This is what
39 * is printed in the end as a single line in the trace output, such as:
41 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
47 unsigned char preempt_count
;
53 * Function trace entry - function address and parent function addres:
56 struct trace_entry ent
;
58 unsigned long parent_ip
;
61 /* Function call entry */
62 struct ftrace_graph_ent_entry
{
63 struct trace_entry ent
;
64 struct ftrace_graph_ent graph_ent
;
67 /* Function return entry */
68 struct ftrace_graph_ret_entry
{
69 struct trace_entry ent
;
70 struct ftrace_graph_ret ret
;
72 extern struct tracer boot_tracer
;
75 * Context switch trace entry - which task (and prio) we switched from/to:
77 struct ctx_switch_entry
{
78 struct trace_entry ent
;
79 unsigned int prev_pid
;
80 unsigned char prev_prio
;
81 unsigned char prev_state
;
82 unsigned int next_pid
;
83 unsigned char next_prio
;
84 unsigned char next_state
;
85 unsigned int next_cpu
;
89 * Special (free-form) trace entry:
91 struct special_entry
{
92 struct trace_entry ent
;
102 #define FTRACE_STACK_ENTRIES 8
105 struct trace_entry ent
;
106 unsigned long caller
[FTRACE_STACK_ENTRIES
];
109 struct userstack_entry
{
110 struct trace_entry ent
;
111 unsigned long caller
[FTRACE_STACK_ENTRIES
];
115 * ftrace_printk entry:
118 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];
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
180 * CONT - multiple entries hold the trace item
182 enum trace_flag_type
{
183 TRACE_FLAG_IRQS_OFF
= 0x01,
184 TRACE_FLAG_IRQS_NOSUPPORT
= 0x02,
185 TRACE_FLAG_NEED_RESCHED
= 0x04,
186 TRACE_FLAG_HARDIRQ
= 0x08,
187 TRACE_FLAG_SOFTIRQ
= 0x10,
188 TRACE_FLAG_CONT
= 0x20,
191 #define TRACE_BUF_SIZE 1024
194 * The CPU trace array - it consists of thousands of trace entries
195 * plus some other descriptor data: (for example which task started
198 struct trace_array_cpu
{
201 /* these fields get copied into max-trace: */
202 unsigned long trace_idx
;
203 unsigned long overrun
;
204 unsigned long saved_latency
;
205 unsigned long critical_start
;
206 unsigned long critical_end
;
207 unsigned long critical_sequence
;
209 unsigned long policy
;
210 unsigned long rt_priority
;
211 cycle_t preempt_timestamp
;
214 char comm
[TASK_COMM_LEN
];
217 struct trace_iterator
;
220 * The trace array - an array of per-CPU trace arrays. This is the
221 * highest level data structure that individual tracers deal with.
222 * They have on/off state as well:
225 struct ring_buffer
*buffer
;
226 unsigned long entries
;
229 struct task_struct
*waiter
;
230 struct trace_array_cpu
*data
[NR_CPUS
];
233 #define FTRACE_CMP_TYPE(var, type) \
234 __builtin_types_compatible_p(typeof(var), type *)
237 #define IF_ASSIGN(var, entry, etype, id) \
238 if (FTRACE_CMP_TYPE(var, etype)) { \
239 var = (typeof(var))(entry); \
240 WARN_ON(id && (entry)->type != id); \
244 /* Will cause compile errors if type is not found. */
245 extern void __ftrace_bad_type(void);
248 * The trace_assign_type is a verifier that the entry type is
249 * the same as the type being assigned. To add new types simply
250 * add a line with the following format:
252 * IF_ASSIGN(var, ent, type, id);
254 * Where "type" is the trace type that includes the trace_entry
255 * as the "ent" item. And "id" is the trace identifier that is
256 * used in the trace_type enum.
258 * If the type can have more than one id, then use zero.
260 #define trace_assign_type(var, ent) \
262 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
263 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
264 IF_ASSIGN(var, ent, struct trace_field_cont, TRACE_CONT); \
265 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
266 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
267 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
268 IF_ASSIGN(var, ent, struct special_entry, 0); \
269 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
271 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
273 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
274 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
275 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
276 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
278 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
280 IF_ASSIGN(var, ent, struct bts_entry, TRACE_BTS);\
281 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
282 __ftrace_bad_type(); \
285 /* Return values for print_line callback */
287 TRACE_TYPE_PARTIAL_LINE
= 0, /* Retry after flushing the seq */
288 TRACE_TYPE_HANDLED
= 1,
289 TRACE_TYPE_UNHANDLED
= 2 /* Relay to other output functions */
294 * An option specific to a tracer. This is a boolean value.
295 * The bit is the bit index that sets its value on the
296 * flags value in struct tracer_flags.
299 const char *name
; /* Will appear on the trace_options file */
300 u32 bit
; /* Mask assigned in val field in tracer_flags */
304 * The set of specific options for a tracer. Your tracer
305 * have to set the initial value of the flags val.
307 struct tracer_flags
{
309 struct tracer_opt
*opts
;
312 /* Makes more easy to define a tracer opt */
313 #define TRACER_OPT(s, b) .name = #s, .bit = b
316 * A specific tracer, represented by methods that operate on a trace array:
320 /* Your tracer should raise a warning if init fails */
321 int (*init
)(struct trace_array
*tr
);
322 void (*reset
)(struct trace_array
*tr
);
323 void (*start
)(struct trace_array
*tr
);
324 void (*stop
)(struct trace_array
*tr
);
325 void (*open
)(struct trace_iterator
*iter
);
326 void (*pipe_open
)(struct trace_iterator
*iter
);
327 void (*close
)(struct trace_iterator
*iter
);
328 ssize_t (*read
)(struct trace_iterator
*iter
,
329 struct file
*filp
, char __user
*ubuf
,
330 size_t cnt
, loff_t
*ppos
);
331 #ifdef CONFIG_FTRACE_STARTUP_TEST
332 int (*selftest
)(struct tracer
*trace
,
333 struct trace_array
*tr
);
335 void (*print_header
)(struct seq_file
*m
);
336 enum print_line_t (*print_line
)(struct trace_iterator
*iter
);
337 /* If you handled the flag setting, return 0 */
338 int (*set_flag
)(u32 old_flags
, u32 bit
, int set
);
341 struct tracer_flags
*flags
;
345 unsigned char buffer
[PAGE_SIZE
];
347 unsigned int readpos
;
351 * Trace iterator - used by printout routines who present trace
352 * results to users and which routines might sleep, etc:
354 struct trace_iterator
{
355 struct trace_array
*tr
;
356 struct tracer
*trace
;
358 struct ring_buffer_iter
*buffer_iter
[NR_CPUS
];
360 /* The below is zeroed out in pipe_read */
361 struct trace_seq seq
;
362 struct trace_entry
*ent
;
366 unsigned long iter_flags
;
373 int tracing_is_enabled(void);
374 void trace_wake_up(void);
375 void tracing_reset(struct trace_array
*tr
, int cpu
);
376 int tracing_open_generic(struct inode
*inode
, struct file
*filp
);
377 struct dentry
*tracing_init_dentry(void);
378 void init_tracer_sysprof_debugfs(struct dentry
*d_tracer
);
380 struct trace_entry
*tracing_get_trace_entry(struct trace_array
*tr
,
381 struct trace_array_cpu
*data
);
382 void tracing_generic_entry_update(struct trace_entry
*entry
,
386 void ftrace(struct trace_array
*tr
,
387 struct trace_array_cpu
*data
,
389 unsigned long parent_ip
,
390 unsigned long flags
, int pc
);
391 void tracing_sched_switch_trace(struct trace_array
*tr
,
392 struct trace_array_cpu
*data
,
393 struct task_struct
*prev
,
394 struct task_struct
*next
,
395 unsigned long flags
, int pc
);
396 void tracing_record_cmdline(struct task_struct
*tsk
);
398 void tracing_sched_wakeup_trace(struct trace_array
*tr
,
399 struct trace_array_cpu
*data
,
400 struct task_struct
*wakee
,
401 struct task_struct
*cur
,
402 unsigned long flags
, int pc
);
403 void trace_special(struct trace_array
*tr
,
404 struct trace_array_cpu
*data
,
407 unsigned long arg3
, int pc
);
408 void trace_function(struct trace_array
*tr
,
409 struct trace_array_cpu
*data
,
411 unsigned long parent_ip
,
412 unsigned long flags
, int pc
);
414 void trace_graph_return(struct ftrace_graph_ret
*trace
);
415 void trace_graph_entry(struct ftrace_graph_ent
*trace
);
416 void trace_bts(struct trace_array
*tr
,
420 void tracing_start_cmdline_record(void);
421 void tracing_stop_cmdline_record(void);
422 void tracing_sched_switch_assign_trace(struct trace_array
*tr
);
423 void tracing_stop_sched_switch_record(void);
424 void tracing_start_sched_switch_record(void);
425 int register_tracer(struct tracer
*type
);
426 void unregister_tracer(struct tracer
*type
);
428 extern unsigned long nsecs_to_usecs(unsigned long nsecs
);
430 extern unsigned long tracing_max_latency
;
431 extern unsigned long tracing_thresh
;
433 void update_max_tr(struct trace_array
*tr
, struct task_struct
*tsk
, int cpu
);
434 void update_max_tr_single(struct trace_array
*tr
,
435 struct task_struct
*tsk
, int cpu
);
437 extern cycle_t
ftrace_now(int cpu
);
439 #ifdef CONFIG_FUNCTION_TRACER
440 void tracing_start_function_trace(void);
441 void tracing_stop_function_trace(void);
443 # define tracing_start_function_trace() do { } while (0)
444 # define tracing_stop_function_trace() do { } while (0)
447 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
449 (*tracer_switch_func_t
)(void *private,
451 struct task_struct
*prev
,
452 struct task_struct
*next
);
454 struct tracer_switch_ops
{
455 tracer_switch_func_t func
;
457 struct tracer_switch_ops
*next
;
460 char *trace_find_cmdline(int pid
);
461 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
463 #ifdef CONFIG_DYNAMIC_FTRACE
464 extern unsigned long ftrace_update_tot_cnt
;
465 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
466 extern int DYN_FTRACE_TEST_NAME(void);
469 #ifdef CONFIG_FTRACE_STARTUP_TEST
470 extern int trace_selftest_startup_function(struct tracer
*trace
,
471 struct trace_array
*tr
);
472 extern int trace_selftest_startup_irqsoff(struct tracer
*trace
,
473 struct trace_array
*tr
);
474 extern int trace_selftest_startup_preemptoff(struct tracer
*trace
,
475 struct trace_array
*tr
);
476 extern int trace_selftest_startup_preemptirqsoff(struct tracer
*trace
,
477 struct trace_array
*tr
);
478 extern int trace_selftest_startup_wakeup(struct tracer
*trace
,
479 struct trace_array
*tr
);
480 extern int trace_selftest_startup_nop(struct tracer
*trace
,
481 struct trace_array
*tr
);
482 extern int trace_selftest_startup_sched_switch(struct tracer
*trace
,
483 struct trace_array
*tr
);
484 extern int trace_selftest_startup_sysprof(struct tracer
*trace
,
485 struct trace_array
*tr
);
486 extern int trace_selftest_startup_branch(struct tracer
*trace
,
487 struct trace_array
*tr
);
488 #endif /* CONFIG_FTRACE_STARTUP_TEST */
490 extern void *head_page(struct trace_array_cpu
*data
);
491 extern int trace_seq_printf(struct trace_seq
*s
, const char *fmt
, ...);
492 extern void trace_seq_print_cont(struct trace_seq
*s
,
493 struct trace_iterator
*iter
);
496 seq_print_ip_sym(struct trace_seq
*s
, unsigned long ip
,
497 unsigned long sym_flags
);
498 extern ssize_t
trace_seq_to_user(struct trace_seq
*s
, char __user
*ubuf
,
500 extern long ns2usecs(cycle_t nsec
);
501 extern int trace_vprintk(unsigned long ip
, const char *fmt
, va_list args
);
503 extern unsigned long trace_flags
;
505 /* Standard output formatting function used for function return traces */
506 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
507 extern enum print_line_t
print_graph_function(struct trace_iterator
*iter
);
509 static inline enum print_line_t
510 print_graph_function(struct trace_iterator
*iter
)
512 return TRACE_TYPE_UNHANDLED
;
517 * trace_iterator_flags is an enumeration that defines bit
518 * positions into trace_flags that controls the output.
520 * NOTE: These bits must match the trace_options array in
523 enum trace_iterator_flags
{
524 TRACE_ITER_PRINT_PARENT
= 0x01,
525 TRACE_ITER_SYM_OFFSET
= 0x02,
526 TRACE_ITER_SYM_ADDR
= 0x04,
527 TRACE_ITER_VERBOSE
= 0x08,
528 TRACE_ITER_RAW
= 0x10,
529 TRACE_ITER_HEX
= 0x20,
530 TRACE_ITER_BIN
= 0x40,
531 TRACE_ITER_BLOCK
= 0x80,
532 TRACE_ITER_STACKTRACE
= 0x100,
533 TRACE_ITER_SCHED_TREE
= 0x200,
534 TRACE_ITER_PRINTK
= 0x400,
535 TRACE_ITER_PREEMPTONLY
= 0x800,
536 TRACE_ITER_BRANCH
= 0x1000,
537 TRACE_ITER_ANNOTATE
= 0x2000,
538 TRACE_ITER_USERSTACKTRACE
= 0x4000,
539 TRACE_ITER_SYM_USEROBJ
= 0x8000
543 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
544 * control the output of kernel symbols.
546 #define TRACE_ITER_SYM_MASK \
547 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
549 extern struct tracer nop_trace
;
552 * ftrace_preempt_disable - disable preemption scheduler safe
554 * When tracing can happen inside the scheduler, there exists
555 * cases that the tracing might happen before the need_resched
556 * flag is checked. If this happens and the tracer calls
557 * preempt_enable (after a disable), a schedule might take place
558 * causing an infinite recursion.
560 * To prevent this, we read the need_recshed flag before
561 * disabling preemption. When we want to enable preemption we
562 * check the flag, if it is set, then we call preempt_enable_no_resched.
563 * Otherwise, we call preempt_enable.
565 * The rational for doing the above is that if need resched is set
566 * and we have yet to reschedule, we are either in an atomic location
567 * (where we do not need to check for scheduling) or we are inside
568 * the scheduler and do not want to resched.
570 static inline int ftrace_preempt_disable(void)
574 resched
= need_resched();
575 preempt_disable_notrace();
581 * ftrace_preempt_enable - enable preemption scheduler safe
582 * @resched: the return value from ftrace_preempt_disable
584 * This is a scheduler safe way to enable preemption and not miss
585 * any preemption checks. The disabled saved the state of preemption.
586 * If resched is set, then we were either inside an atomic or
587 * are inside the scheduler (we would have already scheduled
588 * otherwise). In this case, we do not want to call normal
589 * preempt_enable, but preempt_enable_no_resched instead.
591 static inline void ftrace_preempt_enable(int resched
)
594 preempt_enable_no_resched_notrace();
596 preempt_enable_notrace();
599 #ifdef CONFIG_BRANCH_TRACER
600 extern int enable_branch_tracing(struct trace_array
*tr
);
601 extern void disable_branch_tracing(void);
602 static inline int trace_branch_enable(struct trace_array
*tr
)
604 if (trace_flags
& TRACE_ITER_BRANCH
)
605 return enable_branch_tracing(tr
);
608 static inline void trace_branch_disable(void)
610 /* due to races, always disable */
611 disable_branch_tracing();
614 static inline int trace_branch_enable(struct trace_array
*tr
)
618 static inline void trace_branch_disable(void)
621 #endif /* CONFIG_BRANCH_TRACER */
623 #endif /* _LINUX_KERNEL_TRACE_H */