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,
36 * The trace entry - the most basic unit of tracing. This is what
37 * is printed in the end as a single line in the trace output, such as:
39 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
45 unsigned char preempt_count;
51 * Function trace entry - function address and parent function addres:
54 struct trace_entry ent;
56 unsigned long parent_ip;
59 /* Function return entry */
60 struct ftrace_graph_entry {
61 struct trace_entry ent;
63 unsigned long parent_ip;
64 unsigned long long calltime;
65 unsigned long long rettime;
66 unsigned long overrun;
68 extern struct tracer boot_tracer;
71 * Context switch trace entry - which task (and prio) we switched from/to:
73 struct ctx_switch_entry {
74 struct trace_entry ent;
75 unsigned int prev_pid;
76 unsigned char prev_prio;
77 unsigned char prev_state;
78 unsigned int next_pid;
79 unsigned char next_prio;
80 unsigned char next_state;
81 unsigned int next_cpu;
85 * Special (free-form) trace entry:
87 struct special_entry {
88 struct trace_entry ent;
98 #define FTRACE_STACK_ENTRIES 8
101 struct trace_entry ent;
102 unsigned long caller[FTRACE_STACK_ENTRIES];
105 struct userstack_entry {
106 struct trace_entry ent;
107 unsigned long caller[FTRACE_STACK_ENTRIES];
111 * ftrace_printk entry:
114 struct trace_entry ent;
119 #define TRACE_OLD_SIZE 88
121 struct trace_field_cont {
123 /* Temporary till we get rid of this completely */
124 char buf[TRACE_OLD_SIZE - 1];
127 struct trace_mmiotrace_rw {
128 struct trace_entry ent;
129 struct mmiotrace_rw rw;
132 struct trace_mmiotrace_map {
133 struct trace_entry ent;
134 struct mmiotrace_map map;
137 struct trace_boot_call {
138 struct trace_entry ent;
139 struct boot_trace_call boot_call;
142 struct trace_boot_ret {
143 struct trace_entry ent;
144 struct boot_trace_ret boot_ret;
147 #define TRACE_FUNC_SIZE 30
148 #define TRACE_FILE_SIZE 20
149 struct trace_branch {
150 struct trace_entry ent;
152 char func[TRACE_FUNC_SIZE+1];
153 char file[TRACE_FILE_SIZE+1];
158 struct trace_entry ent;
164 * trace_flag_type is an enumeration that holds different
165 * states when a trace occurs. These are:
166 * IRQS_OFF - interrupts were disabled
167 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
168 * NEED_RESCED - reschedule is requested
169 * HARDIRQ - inside an interrupt handler
170 * SOFTIRQ - inside a softirq handler
171 * CONT - multiple entries hold the trace item
173 enum trace_flag_type {
174 TRACE_FLAG_IRQS_OFF = 0x01,
175 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
176 TRACE_FLAG_NEED_RESCHED = 0x04,
177 TRACE_FLAG_HARDIRQ = 0x08,
178 TRACE_FLAG_SOFTIRQ = 0x10,
179 TRACE_FLAG_CONT = 0x20,
182 #define TRACE_BUF_SIZE 1024
185 * The CPU trace array - it consists of thousands of trace entries
186 * plus some other descriptor data: (for example which task started
189 struct trace_array_cpu {
192 /* these fields get copied into max-trace: */
193 unsigned long trace_idx;
194 unsigned long overrun;
195 unsigned long saved_latency;
196 unsigned long critical_start;
197 unsigned long critical_end;
198 unsigned long critical_sequence;
200 unsigned long policy;
201 unsigned long rt_priority;
202 cycle_t preempt_timestamp;
205 char comm[TASK_COMM_LEN];
208 struct trace_iterator;
211 * The trace array - an array of per-CPU trace arrays. This is the
212 * highest level data structure that individual tracers deal with.
213 * They have on/off state as well:
216 struct ring_buffer *buffer;
217 unsigned long entries;
220 struct task_struct *waiter;
221 struct trace_array_cpu *data[NR_CPUS];
224 #define FTRACE_CMP_TYPE(var, type) \
225 __builtin_types_compatible_p(typeof(var), type *)
228 #define IF_ASSIGN(var, entry, etype, id) \
229 if (FTRACE_CMP_TYPE(var, etype)) { \
230 var = (typeof(var))(entry); \
231 WARN_ON(id && (entry)->type != id); \
235 /* Will cause compile errors if type is not found. */
236 extern void __ftrace_bad_type(void);
239 * The trace_assign_type is a verifier that the entry type is
240 * the same as the type being assigned. To add new types simply
241 * add a line with the following format:
243 * IF_ASSIGN(var, ent, type, id);
245 * Where "type" is the trace type that includes the trace_entry
246 * as the "ent" item. And "id" is the trace identifier that is
247 * used in the trace_type enum.
249 * If the type can have more than one id, then use zero.
251 #define trace_assign_type(var, ent) \
253 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
254 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
255 IF_ASSIGN(var, ent, struct trace_field_cont, TRACE_CONT); \
256 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
257 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
258 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
259 IF_ASSIGN(var, ent, struct special_entry, 0); \
260 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
262 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
264 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
265 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
266 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
267 IF_ASSIGN(var, ent, struct ftrace_graph_entry, TRACE_FN_RET);\
268 IF_ASSIGN(var, ent, struct bts_entry, TRACE_BTS);\
269 __ftrace_bad_type(); \
272 /* Return values for print_line callback */
274 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
275 TRACE_TYPE_HANDLED = 1,
276 TRACE_TYPE_UNHANDLED = 2 /* Relay to other output functions */
281 * An option specific to a tracer. This is a boolean value.
282 * The bit is the bit index that sets its value on the
283 * flags value in struct tracer_flags.
286 const char *name; /* Will appear on the trace_options file */
287 u32 bit; /* Mask assigned in val field in tracer_flags */
291 * The set of specific options for a tracer. Your tracer
292 * have to set the initial value of the flags val.
294 struct tracer_flags {
296 struct tracer_opt *opts;
299 /* Makes more easy to define a tracer opt */
300 #define TRACER_OPT(s, b) .name = #s, .bit = b
303 * A specific tracer, represented by methods that operate on a trace array:
307 /* Your tracer should raise a warning if init fails */
308 int (*init)(struct trace_array *tr);
309 void (*reset)(struct trace_array *tr);
310 void (*start)(struct trace_array *tr);
311 void (*stop)(struct trace_array *tr);
312 void (*open)(struct trace_iterator *iter);
313 void (*pipe_open)(struct trace_iterator *iter);
314 void (*close)(struct trace_iterator *iter);
315 ssize_t (*read)(struct trace_iterator *iter,
316 struct file *filp, char __user *ubuf,
317 size_t cnt, loff_t *ppos);
318 #ifdef CONFIG_FTRACE_STARTUP_TEST
319 int (*selftest)(struct tracer *trace,
320 struct trace_array *tr);
322 void (*print_header)(struct seq_file *m);
323 enum print_line_t (*print_line)(struct trace_iterator *iter);
324 /* If you handled the flag setting, return 0 */
325 int (*set_flag)(u32 old_flags, u32 bit, int set);
328 struct tracer_flags *flags;
332 unsigned char buffer[PAGE_SIZE];
334 unsigned int readpos;
338 * Trace iterator - used by printout routines who present trace
339 * results to users and which routines might sleep, etc:
341 struct trace_iterator {
342 struct trace_array *tr;
343 struct tracer *trace;
345 struct ring_buffer_iter *buffer_iter[NR_CPUS];
347 /* The below is zeroed out in pipe_read */
348 struct trace_seq seq;
349 struct trace_entry *ent;
353 unsigned long iter_flags;
360 int tracing_is_enabled(void);
361 void trace_wake_up(void);
362 void tracing_reset(struct trace_array *tr, int cpu);
363 int tracing_open_generic(struct inode *inode, struct file *filp);
364 struct dentry *tracing_init_dentry(void);
365 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
367 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
368 struct trace_array_cpu *data);
369 void tracing_generic_entry_update(struct trace_entry *entry,
373 void ftrace(struct trace_array *tr,
374 struct trace_array_cpu *data,
376 unsigned long parent_ip,
377 unsigned long flags, int pc);
378 void tracing_sched_switch_trace(struct trace_array *tr,
379 struct trace_array_cpu *data,
380 struct task_struct *prev,
381 struct task_struct *next,
382 unsigned long flags, int pc);
383 void tracing_record_cmdline(struct task_struct *tsk);
385 void tracing_sched_wakeup_trace(struct trace_array *tr,
386 struct trace_array_cpu *data,
387 struct task_struct *wakee,
388 struct task_struct *cur,
389 unsigned long flags, int pc);
390 void trace_special(struct trace_array *tr,
391 struct trace_array_cpu *data,
394 unsigned long arg3, int pc);
395 void trace_function(struct trace_array *tr,
396 struct trace_array_cpu *data,
398 unsigned long parent_ip,
399 unsigned long flags, int pc);
401 trace_function_graph(struct ftrace_graph_ret *trace);
403 void trace_bts(struct trace_array *tr,
407 void tracing_start_cmdline_record(void);
408 void tracing_stop_cmdline_record(void);
409 void tracing_sched_switch_assign_trace(struct trace_array *tr);
410 void tracing_stop_sched_switch_record(void);
411 void tracing_start_sched_switch_record(void);
412 int register_tracer(struct tracer *type);
413 void unregister_tracer(struct tracer *type);
415 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
417 extern unsigned long tracing_max_latency;
418 extern unsigned long tracing_thresh;
420 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
421 void update_max_tr_single(struct trace_array *tr,
422 struct task_struct *tsk, int cpu);
424 extern cycle_t ftrace_now(int cpu);
426 #ifdef CONFIG_FUNCTION_TRACER
427 void tracing_start_function_trace(void);
428 void tracing_stop_function_trace(void);
430 # define tracing_start_function_trace() do { } while (0)
431 # define tracing_stop_function_trace() do { } while (0)
434 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
436 (*tracer_switch_func_t)(void *private,
438 struct task_struct *prev,
439 struct task_struct *next);
441 struct tracer_switch_ops {
442 tracer_switch_func_t func;
444 struct tracer_switch_ops *next;
447 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */
449 #ifdef CONFIG_DYNAMIC_FTRACE
450 extern unsigned long ftrace_update_tot_cnt;
451 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
452 extern int DYN_FTRACE_TEST_NAME(void);
455 #ifdef CONFIG_FTRACE_STARTUP_TEST
456 extern int trace_selftest_startup_function(struct tracer *trace,
457 struct trace_array *tr);
458 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
459 struct trace_array *tr);
460 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
461 struct trace_array *tr);
462 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
463 struct trace_array *tr);
464 extern int trace_selftest_startup_wakeup(struct tracer *trace,
465 struct trace_array *tr);
466 extern int trace_selftest_startup_nop(struct tracer *trace,
467 struct trace_array *tr);
468 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
469 struct trace_array *tr);
470 extern int trace_selftest_startup_sysprof(struct tracer *trace,
471 struct trace_array *tr);
472 extern int trace_selftest_startup_branch(struct tracer *trace,
473 struct trace_array *tr);
474 #endif /* CONFIG_FTRACE_STARTUP_TEST */
476 extern void *head_page(struct trace_array_cpu *data);
477 extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
478 extern void trace_seq_print_cont(struct trace_seq *s,
479 struct trace_iterator *iter);
482 seq_print_ip_sym(struct trace_seq *s, unsigned long ip,
483 unsigned long sym_flags);
484 extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
486 extern long ns2usecs(cycle_t nsec);
487 extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args);
489 extern unsigned long trace_flags;
491 /* Standard output formatting function used for function return traces */
492 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
493 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
495 static inline enum print_line_t
496 print_graph_function(struct trace_iterator *iter)
498 return TRACE_TYPE_UNHANDLED;
503 * trace_iterator_flags is an enumeration that defines bit
504 * positions into trace_flags that controls the output.
506 * NOTE: These bits must match the trace_options array in
509 enum trace_iterator_flags {
510 TRACE_ITER_PRINT_PARENT = 0x01,
511 TRACE_ITER_SYM_OFFSET = 0x02,
512 TRACE_ITER_SYM_ADDR = 0x04,
513 TRACE_ITER_VERBOSE = 0x08,
514 TRACE_ITER_RAW = 0x10,
515 TRACE_ITER_HEX = 0x20,
516 TRACE_ITER_BIN = 0x40,
517 TRACE_ITER_BLOCK = 0x80,
518 TRACE_ITER_STACKTRACE = 0x100,
519 TRACE_ITER_SCHED_TREE = 0x200,
520 TRACE_ITER_PRINTK = 0x400,
521 TRACE_ITER_PREEMPTONLY = 0x800,
522 TRACE_ITER_BRANCH = 0x1000,
523 TRACE_ITER_ANNOTATE = 0x2000,
524 TRACE_ITER_USERSTACKTRACE = 0x4000,
525 TRACE_ITER_SYM_USEROBJ = 0x8000
529 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
530 * control the output of kernel symbols.
532 #define TRACE_ITER_SYM_MASK \
533 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
535 extern struct tracer nop_trace;
538 * ftrace_preempt_disable - disable preemption scheduler safe
540 * When tracing can happen inside the scheduler, there exists
541 * cases that the tracing might happen before the need_resched
542 * flag is checked. If this happens and the tracer calls
543 * preempt_enable (after a disable), a schedule might take place
544 * causing an infinite recursion.
546 * To prevent this, we read the need_recshed flag before
547 * disabling preemption. When we want to enable preemption we
548 * check the flag, if it is set, then we call preempt_enable_no_resched.
549 * Otherwise, we call preempt_enable.
551 * The rational for doing the above is that if need resched is set
552 * and we have yet to reschedule, we are either in an atomic location
553 * (where we do not need to check for scheduling) or we are inside
554 * the scheduler and do not want to resched.
556 static inline int ftrace_preempt_disable(void)
560 resched = need_resched();
561 preempt_disable_notrace();
567 * ftrace_preempt_enable - enable preemption scheduler safe
568 * @resched: the return value from ftrace_preempt_disable
570 * This is a scheduler safe way to enable preemption and not miss
571 * any preemption checks. The disabled saved the state of preemption.
572 * If resched is set, then we were either inside an atomic or
573 * are inside the scheduler (we would have already scheduled
574 * otherwise). In this case, we do not want to call normal
575 * preempt_enable, but preempt_enable_no_resched instead.
577 static inline void ftrace_preempt_enable(int resched)
580 preempt_enable_no_resched_notrace();
582 preempt_enable_notrace();
585 #ifdef CONFIG_BRANCH_TRACER
586 extern int enable_branch_tracing(struct trace_array *tr);
587 extern void disable_branch_tracing(void);
588 static inline int trace_branch_enable(struct trace_array *tr)
590 if (trace_flags & TRACE_ITER_BRANCH)
591 return enable_branch_tracing(tr);
594 static inline void trace_branch_disable(void)
596 /* due to races, always disable */
597 disable_branch_tracing();
600 static inline int trace_branch_enable(struct trace_array *tr)
604 static inline void trace_branch_disable(void)
607 #endif /* CONFIG_BRANCH_TRACER */
609 #endif /* _LINUX_KERNEL_TRACE_H */