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 * ftrace_printk entry:
121 struct trace_entry ent;
127 #define TRACE_OLD_SIZE 88
129 struct trace_field_cont {
131 /* Temporary till we get rid of this completely */
132 char buf[TRACE_OLD_SIZE - 1];
135 struct trace_mmiotrace_rw {
136 struct trace_entry ent;
137 struct mmiotrace_rw rw;
140 struct trace_mmiotrace_map {
141 struct trace_entry ent;
142 struct mmiotrace_map map;
145 struct trace_boot_call {
146 struct trace_entry ent;
147 struct boot_trace_call boot_call;
150 struct trace_boot_ret {
151 struct trace_entry ent;
152 struct boot_trace_ret boot_ret;
155 #define TRACE_FUNC_SIZE 30
156 #define TRACE_FILE_SIZE 20
157 struct trace_branch {
158 struct trace_entry ent;
160 char func[TRACE_FUNC_SIZE+1];
161 char file[TRACE_FILE_SIZE+1];
165 struct hw_branch_entry {
166 struct trace_entry ent;
172 struct trace_entry ent;
173 struct power_trace state_data;
176 struct kmemtrace_alloc_entry {
177 struct trace_entry ent;
178 enum kmemtrace_type_id type_id;
179 unsigned long call_site;
187 struct kmemtrace_free_entry {
188 struct trace_entry ent;
189 enum kmemtrace_type_id type_id;
190 unsigned long call_site;
195 * trace_flag_type is an enumeration that holds different
196 * states when a trace occurs. These are:
197 * IRQS_OFF - interrupts were disabled
198 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
199 * NEED_RESCED - reschedule is requested
200 * HARDIRQ - inside an interrupt handler
201 * SOFTIRQ - inside a softirq handler
203 enum trace_flag_type {
204 TRACE_FLAG_IRQS_OFF = 0x01,
205 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
206 TRACE_FLAG_NEED_RESCHED = 0x04,
207 TRACE_FLAG_HARDIRQ = 0x08,
208 TRACE_FLAG_SOFTIRQ = 0x10,
211 #define TRACE_BUF_SIZE 1024
214 * The CPU trace array - it consists of thousands of trace entries
215 * plus some other descriptor data: (for example which task started
218 struct trace_array_cpu {
221 /* these fields get copied into max-trace: */
222 unsigned long trace_idx;
223 unsigned long overrun;
224 unsigned long saved_latency;
225 unsigned long critical_start;
226 unsigned long critical_end;
227 unsigned long critical_sequence;
229 unsigned long policy;
230 unsigned long rt_priority;
231 cycle_t preempt_timestamp;
234 char comm[TASK_COMM_LEN];
237 struct trace_iterator;
240 * The trace array - an array of per-CPU trace arrays. This is the
241 * highest level data structure that individual tracers deal with.
242 * They have on/off state as well:
245 struct ring_buffer *buffer;
246 unsigned long entries;
249 struct task_struct *waiter;
250 struct trace_array_cpu *data[NR_CPUS];
253 #define FTRACE_CMP_TYPE(var, type) \
254 __builtin_types_compatible_p(typeof(var), type *)
257 #define IF_ASSIGN(var, entry, etype, id) \
258 if (FTRACE_CMP_TYPE(var, etype)) { \
259 var = (typeof(var))(entry); \
260 WARN_ON(id && (entry)->type != id); \
264 /* Will cause compile errors if type is not found. */
265 extern void __ftrace_bad_type(void);
268 * The trace_assign_type is a verifier that the entry type is
269 * the same as the type being assigned. To add new types simply
270 * add a line with the following format:
272 * IF_ASSIGN(var, ent, type, id);
274 * Where "type" is the trace type that includes the trace_entry
275 * as the "ent" item. And "id" is the trace identifier that is
276 * used in the trace_type enum.
278 * If the type can have more than one id, then use zero.
280 #define trace_assign_type(var, ent) \
282 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
283 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
284 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
285 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
286 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
287 IF_ASSIGN(var, ent, struct special_entry, 0); \
288 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
290 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
292 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
293 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
294 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
295 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
297 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
299 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
300 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
301 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
303 IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
305 __ftrace_bad_type(); \
308 /* Return values for print_line callback */
310 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
311 TRACE_TYPE_HANDLED = 1,
312 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
313 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
318 * An option specific to a tracer. This is a boolean value.
319 * The bit is the bit index that sets its value on the
320 * flags value in struct tracer_flags.
323 const char *name; /* Will appear on the trace_options file */
324 u32 bit; /* Mask assigned in val field in tracer_flags */
328 * The set of specific options for a tracer. Your tracer
329 * have to set the initial value of the flags val.
331 struct tracer_flags {
333 struct tracer_opt *opts;
336 /* Makes more easy to define a tracer opt */
337 #define TRACER_OPT(s, b) .name = #s, .bit = b
341 * struct tracer - a specific tracer and its callbacks to interact with debugfs
342 * @name: the name chosen to select it on the available_tracers file
343 * @init: called when one switches to this tracer (echo name > current_tracer)
344 * @reset: called when one switches to another tracer
345 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
346 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
347 * @open: called when the trace file is opened
348 * @pipe_open: called when the trace_pipe file is opened
349 * @wait_pipe: override how the user waits for traces on trace_pipe
350 * @close: called when the trace file is released
351 * @read: override the default read callback on trace_pipe
352 * @splice_read: override the default splice_read callback on trace_pipe
353 * @selftest: selftest to run on boot (see trace_selftest.c)
354 * @print_headers: override the first lines that describe your columns
355 * @print_line: callback that prints a trace
356 * @set_flag: signals one of your private flags changed (trace_options file)
357 * @flags: your private flags
361 int (*init)(struct trace_array *tr);
362 void (*reset)(struct trace_array *tr);
363 void (*start)(struct trace_array *tr);
364 void (*stop)(struct trace_array *tr);
365 void (*open)(struct trace_iterator *iter);
366 void (*pipe_open)(struct trace_iterator *iter);
367 void (*wait_pipe)(struct trace_iterator *iter);
368 void (*close)(struct trace_iterator *iter);
369 ssize_t (*read)(struct trace_iterator *iter,
370 struct file *filp, char __user *ubuf,
371 size_t cnt, loff_t *ppos);
372 ssize_t (*splice_read)(struct trace_iterator *iter,
375 struct pipe_inode_info *pipe,
378 #ifdef CONFIG_FTRACE_STARTUP_TEST
379 int (*selftest)(struct tracer *trace,
380 struct trace_array *tr);
382 void (*print_header)(struct seq_file *m);
383 enum print_line_t (*print_line)(struct trace_iterator *iter);
384 /* If you handled the flag setting, return 0 */
385 int (*set_flag)(u32 old_flags, u32 bit, int set);
388 struct tracer_flags *flags;
389 struct tracer_stat *stats;
393 unsigned char buffer[PAGE_SIZE];
395 unsigned int readpos;
399 * Trace iterator - used by printout routines who present trace
400 * results to users and which routines might sleep, etc:
402 struct trace_iterator {
403 struct trace_array *tr;
404 struct tracer *trace;
406 struct ring_buffer_iter *buffer_iter[NR_CPUS];
408 /* The below is zeroed out in pipe_read */
409 struct trace_seq seq;
410 struct trace_entry *ent;
414 unsigned long iter_flags;
418 cpumask_var_t started;
421 int tracer_init(struct tracer *t, struct trace_array *tr);
422 int tracing_is_enabled(void);
423 void trace_wake_up(void);
424 void tracing_reset(struct trace_array *tr, int cpu);
425 void tracing_reset_online_cpus(struct trace_array *tr);
426 int tracing_open_generic(struct inode *inode, struct file *filp);
427 struct dentry *tracing_init_dentry(void);
428 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
430 struct ring_buffer_event;
432 struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
437 void trace_buffer_unlock_commit(struct trace_array *tr,
438 struct ring_buffer_event *event,
439 unsigned long flags, int pc);
441 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
442 struct trace_array_cpu *data);
444 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
445 int *ent_cpu, u64 *ent_ts);
447 void tracing_generic_entry_update(struct trace_entry *entry,
451 void default_wait_pipe(struct trace_iterator *iter);
452 void poll_wait_pipe(struct trace_iterator *iter);
454 void ftrace(struct trace_array *tr,
455 struct trace_array_cpu *data,
457 unsigned long parent_ip,
458 unsigned long flags, int pc);
459 void tracing_sched_switch_trace(struct trace_array *tr,
460 struct task_struct *prev,
461 struct task_struct *next,
462 unsigned long flags, int pc);
463 void tracing_record_cmdline(struct task_struct *tsk);
465 void tracing_sched_wakeup_trace(struct trace_array *tr,
466 struct task_struct *wakee,
467 struct task_struct *cur,
468 unsigned long flags, int pc);
469 void trace_special(struct trace_array *tr,
470 struct trace_array_cpu *data,
473 unsigned long arg3, int pc);
474 void trace_function(struct trace_array *tr,
476 unsigned long parent_ip,
477 unsigned long flags, int pc);
479 void trace_graph_return(struct ftrace_graph_ret *trace);
480 int trace_graph_entry(struct ftrace_graph_ent *trace);
482 void tracing_start_cmdline_record(void);
483 void tracing_stop_cmdline_record(void);
484 void tracing_sched_switch_assign_trace(struct trace_array *tr);
485 void tracing_stop_sched_switch_record(void);
486 void tracing_start_sched_switch_record(void);
487 int register_tracer(struct tracer *type);
488 void unregister_tracer(struct tracer *type);
490 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
492 extern unsigned long tracing_max_latency;
493 extern unsigned long tracing_thresh;
495 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
496 void update_max_tr_single(struct trace_array *tr,
497 struct task_struct *tsk, int cpu);
499 void __trace_stack(struct trace_array *tr,
503 extern cycle_t ftrace_now(int cpu);
505 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
507 (*tracer_switch_func_t)(void *private,
509 struct task_struct *prev,
510 struct task_struct *next);
512 struct tracer_switch_ops {
513 tracer_switch_func_t func;
515 struct tracer_switch_ops *next;
517 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
519 extern char *trace_find_cmdline(int pid);
521 #ifdef CONFIG_DYNAMIC_FTRACE
522 extern unsigned long ftrace_update_tot_cnt;
523 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
524 extern int DYN_FTRACE_TEST_NAME(void);
527 #ifdef CONFIG_FTRACE_STARTUP_TEST
528 extern int trace_selftest_startup_function(struct tracer *trace,
529 struct trace_array *tr);
530 extern int trace_selftest_startup_function_graph(struct tracer *trace,
531 struct trace_array *tr);
532 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
533 struct trace_array *tr);
534 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
535 struct trace_array *tr);
536 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
537 struct trace_array *tr);
538 extern int trace_selftest_startup_wakeup(struct tracer *trace,
539 struct trace_array *tr);
540 extern int trace_selftest_startup_nop(struct tracer *trace,
541 struct trace_array *tr);
542 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
543 struct trace_array *tr);
544 extern int trace_selftest_startup_sysprof(struct tracer *trace,
545 struct trace_array *tr);
546 extern int trace_selftest_startup_branch(struct tracer *trace,
547 struct trace_array *tr);
548 #endif /* CONFIG_FTRACE_STARTUP_TEST */
550 extern void *head_page(struct trace_array_cpu *data);
551 extern long ns2usecs(cycle_t nsec);
553 trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args);
555 extern unsigned long trace_flags;
557 /* Standard output formatting function used for function return traces */
558 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
559 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
561 #ifdef CONFIG_DYNAMIC_FTRACE
562 /* TODO: make this variable */
563 #define FTRACE_GRAPH_MAX_FUNCS 32
564 extern int ftrace_graph_count;
565 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
567 static inline int ftrace_graph_addr(unsigned long addr)
571 if (!ftrace_graph_count || test_tsk_trace_graph(current))
574 for (i = 0; i < ftrace_graph_count; i++) {
575 if (addr == ftrace_graph_funcs[i])
582 static inline int ftrace_trace_addr(unsigned long addr)
586 static inline int ftrace_graph_addr(unsigned long addr)
590 #endif /* CONFIG_DYNAMIC_FTRACE */
592 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
593 static inline enum print_line_t
594 print_graph_function(struct trace_iterator *iter)
596 return TRACE_TYPE_UNHANDLED;
598 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
600 extern struct pid *ftrace_pid_trace;
602 static inline int ftrace_trace_task(struct task_struct *task)
604 if (!ftrace_pid_trace)
607 return test_tsk_trace_trace(task);
611 * trace_iterator_flags is an enumeration that defines bit
612 * positions into trace_flags that controls the output.
614 * NOTE: These bits must match the trace_options array in
617 enum trace_iterator_flags {
618 TRACE_ITER_PRINT_PARENT = 0x01,
619 TRACE_ITER_SYM_OFFSET = 0x02,
620 TRACE_ITER_SYM_ADDR = 0x04,
621 TRACE_ITER_VERBOSE = 0x08,
622 TRACE_ITER_RAW = 0x10,
623 TRACE_ITER_HEX = 0x20,
624 TRACE_ITER_BIN = 0x40,
625 TRACE_ITER_BLOCK = 0x80,
626 TRACE_ITER_STACKTRACE = 0x100,
627 TRACE_ITER_SCHED_TREE = 0x200,
628 TRACE_ITER_PRINTK = 0x400,
629 TRACE_ITER_PREEMPTONLY = 0x800,
630 TRACE_ITER_BRANCH = 0x1000,
631 TRACE_ITER_ANNOTATE = 0x2000,
632 TRACE_ITER_USERSTACKTRACE = 0x4000,
633 TRACE_ITER_SYM_USEROBJ = 0x8000,
634 TRACE_ITER_PRINTK_MSGONLY = 0x10000,
635 TRACE_ITER_CONTEXT_INFO = 0x20000 /* Print pid/cpu/time */
639 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
640 * control the output of kernel symbols.
642 #define TRACE_ITER_SYM_MASK \
643 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
645 extern struct tracer nop_trace;
648 * ftrace_preempt_disable - disable preemption scheduler safe
650 * When tracing can happen inside the scheduler, there exists
651 * cases that the tracing might happen before the need_resched
652 * flag is checked. If this happens and the tracer calls
653 * preempt_enable (after a disable), a schedule might take place
654 * causing an infinite recursion.
656 * To prevent this, we read the need_resched flag before
657 * disabling preemption. When we want to enable preemption we
658 * check the flag, if it is set, then we call preempt_enable_no_resched.
659 * Otherwise, we call preempt_enable.
661 * The rational for doing the above is that if need_resched is set
662 * and we have yet to reschedule, we are either in an atomic location
663 * (where we do not need to check for scheduling) or we are inside
664 * the scheduler and do not want to resched.
666 static inline int ftrace_preempt_disable(void)
670 resched = need_resched();
671 preempt_disable_notrace();
677 * ftrace_preempt_enable - enable preemption scheduler safe
678 * @resched: the return value from ftrace_preempt_disable
680 * This is a scheduler safe way to enable preemption and not miss
681 * any preemption checks. The disabled saved the state of preemption.
682 * If resched is set, then we are either inside an atomic or
683 * are inside the scheduler (we would have already scheduled
684 * otherwise). In this case, we do not want to call normal
685 * preempt_enable, but preempt_enable_no_resched instead.
687 static inline void ftrace_preempt_enable(int resched)
690 preempt_enable_no_resched_notrace();
692 preempt_enable_notrace();
695 #ifdef CONFIG_BRANCH_TRACER
696 extern int enable_branch_tracing(struct trace_array *tr);
697 extern void disable_branch_tracing(void);
698 static inline int trace_branch_enable(struct trace_array *tr)
700 if (trace_flags & TRACE_ITER_BRANCH)
701 return enable_branch_tracing(tr);
704 static inline void trace_branch_disable(void)
706 /* due to races, always disable */
707 disable_branch_tracing();
710 static inline int trace_branch_enable(struct trace_array *tr)
714 static inline void trace_branch_disable(void)
717 #endif /* CONFIG_BRANCH_TRACER */
719 #endif /* _LINUX_KERNEL_TRACE_H */