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 int 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 #ifdef CONFIG_DYNAMIC_FTRACE
510 /* TODO: make this variable */
511 #define FTRACE_GRAPH_MAX_FUNCS 32
512 extern int ftrace_graph_count;
513 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
515 static inline int ftrace_graph_addr(unsigned long addr)
519 if (!ftrace_graph_count || test_tsk_trace_graph(current))
522 for (i = 0; i < ftrace_graph_count; i++) {
523 if (addr == ftrace_graph_funcs[i])
530 static inline int ftrace_trace_addr(unsigned long addr)
534 #endif /* CONFIG_DYNAMIC_FTRACE */
536 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
537 static inline enum print_line_t
538 print_graph_function(struct trace_iterator *iter)
540 return TRACE_TYPE_UNHANDLED;
542 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
544 extern int ftrace_pid_trace;
546 static inline int ftrace_trace_task(struct task_struct *task)
548 if (ftrace_pid_trace < 0)
551 return test_tsk_trace_trace(task);
555 * trace_iterator_flags is an enumeration that defines bit
556 * positions into trace_flags that controls the output.
558 * NOTE: These bits must match the trace_options array in
561 enum trace_iterator_flags {
562 TRACE_ITER_PRINT_PARENT = 0x01,
563 TRACE_ITER_SYM_OFFSET = 0x02,
564 TRACE_ITER_SYM_ADDR = 0x04,
565 TRACE_ITER_VERBOSE = 0x08,
566 TRACE_ITER_RAW = 0x10,
567 TRACE_ITER_HEX = 0x20,
568 TRACE_ITER_BIN = 0x40,
569 TRACE_ITER_BLOCK = 0x80,
570 TRACE_ITER_STACKTRACE = 0x100,
571 TRACE_ITER_SCHED_TREE = 0x200,
572 TRACE_ITER_PRINTK = 0x400,
573 TRACE_ITER_PREEMPTONLY = 0x800,
574 TRACE_ITER_BRANCH = 0x1000,
575 TRACE_ITER_ANNOTATE = 0x2000,
576 TRACE_ITER_USERSTACKTRACE = 0x4000,
577 TRACE_ITER_SYM_USEROBJ = 0x8000
581 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
582 * control the output of kernel symbols.
584 #define TRACE_ITER_SYM_MASK \
585 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
587 extern struct tracer nop_trace;
590 * ftrace_preempt_disable - disable preemption scheduler safe
592 * When tracing can happen inside the scheduler, there exists
593 * cases that the tracing might happen before the need_resched
594 * flag is checked. If this happens and the tracer calls
595 * preempt_enable (after a disable), a schedule might take place
596 * causing an infinite recursion.
598 * To prevent this, we read the need_recshed flag before
599 * disabling preemption. When we want to enable preemption we
600 * check the flag, if it is set, then we call preempt_enable_no_resched.
601 * Otherwise, we call preempt_enable.
603 * The rational for doing the above is that if need resched is set
604 * and we have yet to reschedule, we are either in an atomic location
605 * (where we do not need to check for scheduling) or we are inside
606 * the scheduler and do not want to resched.
608 static inline int ftrace_preempt_disable(void)
612 resched = need_resched();
613 preempt_disable_notrace();
619 * ftrace_preempt_enable - enable preemption scheduler safe
620 * @resched: the return value from ftrace_preempt_disable
622 * This is a scheduler safe way to enable preemption and not miss
623 * any preemption checks. The disabled saved the state of preemption.
624 * If resched is set, then we were either inside an atomic or
625 * are inside the scheduler (we would have already scheduled
626 * otherwise). In this case, we do not want to call normal
627 * preempt_enable, but preempt_enable_no_resched instead.
629 static inline void ftrace_preempt_enable(int resched)
632 preempt_enable_no_resched_notrace();
634 preempt_enable_notrace();
637 #ifdef CONFIG_BRANCH_TRACER
638 extern int enable_branch_tracing(struct trace_array *tr);
639 extern void disable_branch_tracing(void);
640 static inline int trace_branch_enable(struct trace_array *tr)
642 if (trace_flags & TRACE_ITER_BRANCH)
643 return enable_branch_tracing(tr);
646 static inline void trace_branch_disable(void)
648 /* due to races, always disable */
649 disable_branch_tracing();
652 static inline int trace_branch_enable(struct trace_array *tr)
656 static inline void trace_branch_disable(void)
659 #endif /* CONFIG_BRANCH_TRACER */
661 #endif /* _LINUX_KERNEL_TRACE_H */