1 // SPDX-License-Identifier: GPL-2.0
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/hw_breakpoint.h>
15 #include <linux/trace_seq.h>
16 #include <linux/trace_events.h>
17 #include <linux/compiler.h>
18 #include <linux/glob.h>
20 #ifdef CONFIG_FTRACE_SYSCALLS
21 #include <asm/unistd.h> /* For NR_SYSCALLS */
22 #include <asm/syscall.h> /* some archs define it here */
26 __TRACE_FIRST_TYPE = 0,
50 #define __field(type, item) type item;
53 #define __field_struct(type, item) __field(type, item)
56 #define __field_desc(type, container, item)
59 #define __array(type, item, size) type item[size];
62 #define __array_desc(type, container, item, size)
64 #undef __dynamic_array
65 #define __dynamic_array(type, item) type item[];
68 #define F_STRUCT(args...) args
71 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
72 struct struct_name { \
73 struct trace_entry ent; \
77 #undef FTRACE_ENTRY_DUP
78 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
80 #undef FTRACE_ENTRY_REG
81 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
83 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
86 #undef FTRACE_ENTRY_PACKED
87 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \
89 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
92 #include "trace_entries.h"
95 * syscalls are special, and need special handling, this is why
96 * they are not included in trace_entries.h
98 struct syscall_trace_enter {
99 struct trace_entry ent;
101 unsigned long args[];
104 struct syscall_trace_exit {
105 struct trace_entry ent;
110 struct kprobe_trace_entry_head {
111 struct trace_entry ent;
115 struct kretprobe_trace_entry_head {
116 struct trace_entry ent;
118 unsigned long ret_ip;
122 * trace_flag_type is an enumeration that holds different
123 * states when a trace occurs. These are:
124 * IRQS_OFF - interrupts were disabled
125 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
126 * NEED_RESCHED - reschedule is requested
127 * HARDIRQ - inside an interrupt handler
128 * SOFTIRQ - inside a softirq handler
130 enum trace_flag_type {
131 TRACE_FLAG_IRQS_OFF = 0x01,
132 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
133 TRACE_FLAG_NEED_RESCHED = 0x04,
134 TRACE_FLAG_HARDIRQ = 0x08,
135 TRACE_FLAG_SOFTIRQ = 0x10,
136 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
137 TRACE_FLAG_NMI = 0x40,
140 #define TRACE_BUF_SIZE 1024
145 * The CPU trace array - it consists of thousands of trace entries
146 * plus some other descriptor data: (for example which task started
149 struct trace_array_cpu {
151 void *buffer_page; /* ring buffer spare */
153 unsigned long entries;
154 unsigned long saved_latency;
155 unsigned long critical_start;
156 unsigned long critical_end;
157 unsigned long critical_sequence;
159 unsigned long policy;
160 unsigned long rt_priority;
161 unsigned long skipped_entries;
162 u64 preempt_timestamp;
165 char comm[TASK_COMM_LEN];
168 #ifdef CONFIG_FUNCTION_TRACER
169 bool ftrace_ignore_pid;
174 struct trace_option_dentry;
176 struct trace_buffer {
177 struct trace_array *tr;
178 struct ring_buffer *buffer;
179 struct trace_array_cpu __percpu *data;
184 #define TRACE_FLAGS_MAX_SIZE 32
186 struct trace_options {
187 struct tracer *tracer;
188 struct trace_option_dentry *topts;
191 struct trace_pid_list {
196 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
199 * struct cond_snapshot - conditional snapshot data and callback
201 * The cond_snapshot structure encapsulates a callback function and
202 * data associated with the snapshot for a given tracing instance.
204 * When a snapshot is taken conditionally, by invoking
205 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
206 * passed in turn to the cond_snapshot.update() function. That data
207 * can be compared by the update() implementation with the cond_data
208 * contained wihin the struct cond_snapshot instance associated with
209 * the trace_array. Because the tr->max_lock is held throughout the
210 * update() call, the update() function can directly retrieve the
211 * cond_snapshot and cond_data associated with the per-instance
212 * snapshot associated with the trace_array.
214 * The cond_snapshot.update() implementation can save data to be
215 * associated with the snapshot if it decides to, and returns 'true'
216 * in that case, or it returns 'false' if the conditional snapshot
217 * shouldn't be taken.
219 * The cond_snapshot instance is created and associated with the
220 * user-defined cond_data by tracing_cond_snapshot_enable().
221 * Likewise, the cond_snapshot instance is destroyed and is no longer
222 * associated with the trace instance by
223 * tracing_cond_snapshot_disable().
225 * The method below is required.
227 * @update: When a conditional snapshot is invoked, the update()
228 * callback function is invoked with the tr->max_lock held. The
229 * update() implementation signals whether or not to actually
230 * take the snapshot, by returning 'true' if so, 'false' if no
231 * snapshot should be taken. Because the max_lock is held for
232 * the duration of update(), the implementation is safe to
233 * directly retrieven and save any implementation data it needs
234 * to in association with the snapshot.
236 struct cond_snapshot {
238 cond_update_fn_t update;
242 * The trace array - an array of per-CPU trace arrays. This is the
243 * highest level data structure that individual tracers deal with.
244 * They have on/off state as well:
247 struct list_head list;
249 struct trace_buffer trace_buffer;
250 #ifdef CONFIG_TRACER_MAX_TRACE
252 * The max_buffer is used to snapshot the trace when a maximum
253 * latency is reached, or when the user initiates a snapshot.
254 * Some tracers will use this to store a maximum trace while
255 * it continues examining live traces.
257 * The buffers for the max_buffer are set up the same as the trace_buffer
258 * When a snapshot is taken, the buffer of the max_buffer is swapped
259 * with the buffer of the trace_buffer and the buffers are reset for
260 * the trace_buffer so the tracing can continue.
262 struct trace_buffer max_buffer;
263 bool allocated_snapshot;
265 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
266 unsigned long max_latency;
268 struct trace_pid_list __rcu *filtered_pids;
270 * max_lock is used to protect the swapping of buffers
271 * when taking a max snapshot. The buffers themselves are
272 * protected by per_cpu spinlocks. But the action of the swap
273 * needs its own lock.
275 * This is defined as a arch_spinlock_t in order to help
276 * with performance when lockdep debugging is enabled.
278 * It is also used in other places outside the update_max_tr
279 * so it needs to be defined outside of the
280 * CONFIG_TRACER_MAX_TRACE.
282 arch_spinlock_t max_lock;
284 #ifdef CONFIG_FTRACE_SYSCALLS
285 int sys_refcount_enter;
286 int sys_refcount_exit;
287 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
288 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
295 unsigned int n_err_log_entries;
296 struct tracer *current_trace;
297 unsigned int trace_flags;
298 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
300 raw_spinlock_t start_lock;
301 struct list_head err_log;
303 struct dentry *options;
304 struct dentry *percpu_dir;
305 struct dentry *event_dir;
306 struct trace_options *topts;
307 struct list_head systems;
308 struct list_head events;
309 struct trace_event_file *trace_marker_file;
310 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
312 #ifdef CONFIG_FUNCTION_TRACER
313 struct ftrace_ops *ops;
314 struct trace_pid_list __rcu *function_pids;
315 #ifdef CONFIG_DYNAMIC_FTRACE
316 /* All of these are protected by the ftrace_lock */
317 struct list_head func_probes;
318 struct list_head mod_trace;
319 struct list_head mod_notrace;
321 /* function tracing enabled */
322 int function_enabled;
324 int time_stamp_abs_ref;
325 struct list_head hist_vars;
326 #ifdef CONFIG_TRACER_SNAPSHOT
327 struct cond_snapshot *cond_snapshot;
332 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
335 extern struct list_head ftrace_trace_arrays;
337 extern struct mutex trace_types_lock;
339 extern int trace_array_get(struct trace_array *tr);
340 extern void trace_array_put(struct trace_array *tr);
342 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
343 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
345 extern bool trace_clock_in_ns(struct trace_array *tr);
348 * The global tracer (top) should be the first trace array added,
349 * but we check the flag anyway.
351 static inline struct trace_array *top_trace_array(void)
353 struct trace_array *tr;
355 if (list_empty(&ftrace_trace_arrays))
358 tr = list_entry(ftrace_trace_arrays.prev,
360 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
364 #define FTRACE_CMP_TYPE(var, type) \
365 __builtin_types_compatible_p(typeof(var), type *)
368 #define IF_ASSIGN(var, entry, etype, id) \
369 if (FTRACE_CMP_TYPE(var, etype)) { \
370 var = (typeof(var))(entry); \
371 WARN_ON(id && (entry)->type != id); \
375 /* Will cause compile errors if type is not found. */
376 extern void __ftrace_bad_type(void);
379 * The trace_assign_type is a verifier that the entry type is
380 * the same as the type being assigned. To add new types simply
381 * add a line with the following format:
383 * IF_ASSIGN(var, ent, type, id);
385 * Where "type" is the trace type that includes the trace_entry
386 * as the "ent" item. And "id" is the trace identifier that is
387 * used in the trace_type enum.
389 * If the type can have more than one id, then use zero.
391 #define trace_assign_type(var, ent) \
393 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
394 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
395 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
396 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
397 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
398 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
399 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
400 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
401 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
402 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
404 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
406 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
407 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
409 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
411 __ftrace_bad_type(); \
415 * An option specific to a tracer. This is a boolean value.
416 * The bit is the bit index that sets its value on the
417 * flags value in struct tracer_flags.
420 const char *name; /* Will appear on the trace_options file */
421 u32 bit; /* Mask assigned in val field in tracer_flags */
425 * The set of specific options for a tracer. Your tracer
426 * have to set the initial value of the flags val.
428 struct tracer_flags {
430 struct tracer_opt *opts;
431 struct tracer *trace;
434 /* Makes more easy to define a tracer opt */
435 #define TRACER_OPT(s, b) .name = #s, .bit = b
438 struct trace_option_dentry {
439 struct tracer_opt *opt;
440 struct tracer_flags *flags;
441 struct trace_array *tr;
442 struct dentry *entry;
446 * struct tracer - a specific tracer and its callbacks to interact with tracefs
447 * @name: the name chosen to select it on the available_tracers file
448 * @init: called when one switches to this tracer (echo name > current_tracer)
449 * @reset: called when one switches to another tracer
450 * @start: called when tracing is unpaused (echo 1 > tracing_on)
451 * @stop: called when tracing is paused (echo 0 > tracing_on)
452 * @update_thresh: called when tracing_thresh is updated
453 * @open: called when the trace file is opened
454 * @pipe_open: called when the trace_pipe file is opened
455 * @close: called when the trace file is released
456 * @pipe_close: called when the trace_pipe file is released
457 * @read: override the default read callback on trace_pipe
458 * @splice_read: override the default splice_read callback on trace_pipe
459 * @selftest: selftest to run on boot (see trace_selftest.c)
460 * @print_headers: override the first lines that describe your columns
461 * @print_line: callback that prints a trace
462 * @set_flag: signals one of your private flags changed (trace_options file)
463 * @flags: your private flags
467 int (*init)(struct trace_array *tr);
468 void (*reset)(struct trace_array *tr);
469 void (*start)(struct trace_array *tr);
470 void (*stop)(struct trace_array *tr);
471 int (*update_thresh)(struct trace_array *tr);
472 void (*open)(struct trace_iterator *iter);
473 void (*pipe_open)(struct trace_iterator *iter);
474 void (*close)(struct trace_iterator *iter);
475 void (*pipe_close)(struct trace_iterator *iter);
476 ssize_t (*read)(struct trace_iterator *iter,
477 struct file *filp, char __user *ubuf,
478 size_t cnt, loff_t *ppos);
479 ssize_t (*splice_read)(struct trace_iterator *iter,
482 struct pipe_inode_info *pipe,
485 #ifdef CONFIG_FTRACE_STARTUP_TEST
486 int (*selftest)(struct tracer *trace,
487 struct trace_array *tr);
489 void (*print_header)(struct seq_file *m);
490 enum print_line_t (*print_line)(struct trace_iterator *iter);
491 /* If you handled the flag setting, return 0 */
492 int (*set_flag)(struct trace_array *tr,
493 u32 old_flags, u32 bit, int set);
494 /* Return 0 if OK with change, else return non-zero */
495 int (*flag_changed)(struct trace_array *tr,
498 struct tracer_flags *flags;
502 bool allow_instances;
503 #ifdef CONFIG_TRACER_MAX_TRACE
506 /* True if tracer cannot be enabled in kernel param */
511 /* Only current can touch trace_recursion */
514 * For function tracing recursion:
515 * The order of these bits are important.
517 * When function tracing occurs, the following steps are made:
518 * If arch does not support a ftrace feature:
519 * call internal function (uses INTERNAL bits) which calls...
520 * If callback is registered to the "global" list, the list
521 * function is called and recursion checks the GLOBAL bits.
522 * then this function calls...
523 * The function callback, which can use the FTRACE bits to
524 * check for recursion.
526 * Now if the arch does not suppport a feature, and it calls
527 * the global list function which calls the ftrace callback
528 * all three of these steps will do a recursion protection.
529 * There's no reason to do one if the previous caller already
530 * did. The recursion that we are protecting against will
531 * go through the same steps again.
533 * To prevent the multiple recursion checks, if a recursion
534 * bit is set that is higher than the MAX bit of the current
535 * check, then we know that the check was made by the previous
536 * caller, and we can skip the current check.
540 TRACE_BUFFER_NMI_BIT,
541 TRACE_BUFFER_IRQ_BIT,
542 TRACE_BUFFER_SIRQ_BIT,
544 /* Start of function recursion bits */
546 TRACE_FTRACE_NMI_BIT,
547 TRACE_FTRACE_IRQ_BIT,
548 TRACE_FTRACE_SIRQ_BIT,
550 /* INTERNAL_BITs must be greater than FTRACE_BITs */
552 TRACE_INTERNAL_NMI_BIT,
553 TRACE_INTERNAL_IRQ_BIT,
554 TRACE_INTERNAL_SIRQ_BIT,
558 * Abuse of the trace_recursion.
559 * As we need a way to maintain state if we are tracing the function
560 * graph in irq because we want to trace a particular function that
561 * was called in irq context but we have irq tracing off. Since this
562 * can only be modified by current, we can reuse trace_recursion.
566 /* Set if the function is in the set_graph_function file */
570 * In the very unlikely case that an interrupt came in
571 * at a start of graph tracing, and we want to trace
572 * the function in that interrupt, the depth can be greater
573 * than zero, because of the preempted start of a previous
574 * trace. In an even more unlikely case, depth could be 2
575 * if a softirq interrupted the start of graph tracing,
576 * followed by an interrupt preempting a start of graph
577 * tracing in the softirq, and depth can even be 3
578 * if an NMI came in at the start of an interrupt function
579 * that preempted a softirq start of a function that
580 * preempted normal context!!!! Luckily, it can't be
581 * greater than 3, so the next two bits are a mask
582 * of what the depth is when we set TRACE_GRAPH_BIT
585 TRACE_GRAPH_DEPTH_START_BIT,
586 TRACE_GRAPH_DEPTH_END_BIT,
589 * To implement set_graph_notrace, if this bit is set, we ignore
590 * function graph tracing of called functions, until the return
591 * function is called to clear it.
593 TRACE_GRAPH_NOTRACE_BIT,
596 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
597 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
598 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
600 #define trace_recursion_depth() \
601 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
602 #define trace_recursion_set_depth(depth) \
604 current->trace_recursion &= \
605 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
606 current->trace_recursion |= \
607 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
610 #define TRACE_CONTEXT_BITS 4
612 #define TRACE_FTRACE_START TRACE_FTRACE_BIT
613 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
615 #define TRACE_LIST_START TRACE_INTERNAL_BIT
616 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
618 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX
620 static __always_inline int trace_get_context_bit(void)
624 if (in_interrupt()) {
638 static __always_inline int trace_test_and_set_recursion(int start, int max)
640 unsigned int val = current->trace_recursion;
643 /* A previous recursion check was made */
644 if ((val & TRACE_CONTEXT_MASK) > max)
647 bit = trace_get_context_bit() + start;
648 if (unlikely(val & (1 << bit)))
652 current->trace_recursion = val;
658 static __always_inline void trace_clear_recursion(int bit)
660 unsigned int val = current->trace_recursion;
669 current->trace_recursion = val;
672 static inline struct ring_buffer_iter *
673 trace_buffer_iter(struct trace_iterator *iter, int cpu)
675 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
678 int tracer_init(struct tracer *t, struct trace_array *tr);
679 int tracing_is_enabled(void);
680 void tracing_reset_online_cpus(struct trace_buffer *buf);
681 void tracing_reset_current(int cpu);
682 void tracing_reset_all_online_cpus(void);
683 int tracing_open_generic(struct inode *inode, struct file *filp);
684 bool tracing_is_disabled(void);
685 bool tracer_tracing_is_on(struct trace_array *tr);
686 void tracer_tracing_on(struct trace_array *tr);
687 void tracer_tracing_off(struct trace_array *tr);
688 struct dentry *trace_create_file(const char *name,
690 struct dentry *parent,
692 const struct file_operations *fops);
694 struct dentry *tracing_init_dentry(void);
696 struct ring_buffer_event;
698 struct ring_buffer_event *
699 trace_buffer_lock_reserve(struct ring_buffer *buffer,
705 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
706 struct trace_array_cpu *data);
708 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
709 int *ent_cpu, u64 *ent_ts);
711 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
712 struct ring_buffer_event *event);
714 int trace_empty(struct trace_iterator *iter);
716 void *trace_find_next_entry_inc(struct trace_iterator *iter);
718 void trace_init_global_iter(struct trace_iterator *iter);
720 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
722 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
723 unsigned long trace_total_entries(struct trace_array *tr);
725 void trace_function(struct trace_array *tr,
727 unsigned long parent_ip,
728 unsigned long flags, int pc);
729 void trace_graph_function(struct trace_array *tr,
731 unsigned long parent_ip,
732 unsigned long flags, int pc);
733 void trace_latency_header(struct seq_file *m);
734 void trace_default_header(struct seq_file *m);
735 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
736 int trace_empty(struct trace_iterator *iter);
738 void trace_graph_return(struct ftrace_graph_ret *trace);
739 int trace_graph_entry(struct ftrace_graph_ent *trace);
740 void set_graph_array(struct trace_array *tr);
742 void tracing_start_cmdline_record(void);
743 void tracing_stop_cmdline_record(void);
744 void tracing_start_tgid_record(void);
745 void tracing_stop_tgid_record(void);
747 int register_tracer(struct tracer *type);
748 int is_tracing_stopped(void);
750 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
752 extern cpumask_var_t __read_mostly tracing_buffer_mask;
754 #define for_each_tracing_cpu(cpu) \
755 for_each_cpu(cpu, tracing_buffer_mask)
757 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
759 extern unsigned long tracing_thresh;
765 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
767 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
768 struct task_struct *task);
769 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
770 struct task_struct *self,
771 struct task_struct *task);
772 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
773 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
774 int trace_pid_show(struct seq_file *m, void *v);
775 void trace_free_pid_list(struct trace_pid_list *pid_list);
776 int trace_pid_write(struct trace_pid_list *filtered_pids,
777 struct trace_pid_list **new_pid_list,
778 const char __user *ubuf, size_t cnt);
780 #ifdef CONFIG_TRACER_MAX_TRACE
781 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
783 void update_max_tr_single(struct trace_array *tr,
784 struct task_struct *tsk, int cpu);
785 #endif /* CONFIG_TRACER_MAX_TRACE */
787 #ifdef CONFIG_STACKTRACE
788 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
791 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
795 #endif /* CONFIG_STACKTRACE */
797 extern u64 ftrace_now(int cpu);
799 extern void trace_find_cmdline(int pid, char comm[]);
800 extern int trace_find_tgid(int pid);
801 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
803 #ifdef CONFIG_DYNAMIC_FTRACE
804 extern unsigned long ftrace_update_tot_cnt;
805 void ftrace_init_trace_array(struct trace_array *tr);
807 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
809 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
810 extern int DYN_FTRACE_TEST_NAME(void);
811 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
812 extern int DYN_FTRACE_TEST_NAME2(void);
814 extern bool ring_buffer_expanded;
815 extern bool tracing_selftest_disabled;
817 #ifdef CONFIG_FTRACE_STARTUP_TEST
818 extern int trace_selftest_startup_function(struct tracer *trace,
819 struct trace_array *tr);
820 extern int trace_selftest_startup_function_graph(struct tracer *trace,
821 struct trace_array *tr);
822 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
823 struct trace_array *tr);
824 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
825 struct trace_array *tr);
826 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
827 struct trace_array *tr);
828 extern int trace_selftest_startup_wakeup(struct tracer *trace,
829 struct trace_array *tr);
830 extern int trace_selftest_startup_nop(struct tracer *trace,
831 struct trace_array *tr);
832 extern int trace_selftest_startup_branch(struct tracer *trace,
833 struct trace_array *tr);
835 * Tracer data references selftest functions that only occur
836 * on boot up. These can be __init functions. Thus, when selftests
837 * are enabled, then the tracers need to reference __init functions.
839 #define __tracer_data __refdata
841 /* Tracers are seldom changed. Optimize when selftests are disabled. */
842 #define __tracer_data __read_mostly
843 #endif /* CONFIG_FTRACE_STARTUP_TEST */
845 extern void *head_page(struct trace_array_cpu *data);
846 extern unsigned long long ns2usecs(u64 nsec);
848 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
850 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
852 trace_array_vprintk(struct trace_array *tr,
853 unsigned long ip, const char *fmt, va_list args);
854 int trace_array_printk(struct trace_array *tr,
855 unsigned long ip, const char *fmt, ...);
856 int trace_array_printk_buf(struct ring_buffer *buffer,
857 unsigned long ip, const char *fmt, ...);
858 void trace_printk_seq(struct trace_seq *s);
859 enum print_line_t print_trace_line(struct trace_iterator *iter);
861 extern char trace_find_mark(unsigned long long duration);
865 struct ftrace_mod_load {
866 struct list_head list;
873 FTRACE_HASH_FL_MOD = (1 << 0),
877 unsigned long size_bits;
878 struct hlist_head *buckets;
884 struct ftrace_func_entry *
885 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
887 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
889 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
892 /* Standard output formatting function used for function return traces */
893 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
896 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
897 #define TRACE_GRAPH_PRINT_CPU 0x2
898 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
899 #define TRACE_GRAPH_PRINT_PROC 0x8
900 #define TRACE_GRAPH_PRINT_DURATION 0x10
901 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
902 #define TRACE_GRAPH_PRINT_REL_TIME 0x40
903 #define TRACE_GRAPH_PRINT_IRQS 0x80
904 #define TRACE_GRAPH_PRINT_TAIL 0x100
905 #define TRACE_GRAPH_SLEEP_TIME 0x200
906 #define TRACE_GRAPH_GRAPH_TIME 0x400
907 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
908 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
910 extern void ftrace_graph_sleep_time_control(bool enable);
912 #ifdef CONFIG_FUNCTION_PROFILER
913 extern void ftrace_graph_graph_time_control(bool enable);
915 static inline void ftrace_graph_graph_time_control(bool enable) { }
918 extern enum print_line_t
919 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
920 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
922 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
923 extern void graph_trace_open(struct trace_iterator *iter);
924 extern void graph_trace_close(struct trace_iterator *iter);
925 extern int __trace_graph_entry(struct trace_array *tr,
926 struct ftrace_graph_ent *trace,
927 unsigned long flags, int pc);
928 extern void __trace_graph_return(struct trace_array *tr,
929 struct ftrace_graph_ret *trace,
930 unsigned long flags, int pc);
932 #ifdef CONFIG_DYNAMIC_FTRACE
933 extern struct ftrace_hash *ftrace_graph_hash;
934 extern struct ftrace_hash *ftrace_graph_notrace_hash;
936 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
938 unsigned long addr = trace->func;
941 preempt_disable_notrace();
943 if (ftrace_hash_empty(ftrace_graph_hash)) {
948 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
951 * This needs to be cleared on the return functions
952 * when the depth is zero.
954 trace_recursion_set(TRACE_GRAPH_BIT);
955 trace_recursion_set_depth(trace->depth);
958 * If no irqs are to be traced, but a set_graph_function
959 * is set, and called by an interrupt handler, we still
963 trace_recursion_set(TRACE_IRQ_BIT);
965 trace_recursion_clear(TRACE_IRQ_BIT);
970 preempt_enable_notrace();
974 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
976 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
977 trace->depth == trace_recursion_depth())
978 trace_recursion_clear(TRACE_GRAPH_BIT);
981 static inline int ftrace_graph_notrace_addr(unsigned long addr)
985 preempt_disable_notrace();
987 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
990 preempt_enable_notrace();
994 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
999 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1003 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1005 #endif /* CONFIG_DYNAMIC_FTRACE */
1007 extern unsigned int fgraph_max_depth;
1009 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
1011 /* trace it when it is-nested-in or is a function enabled. */
1012 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
1013 ftrace_graph_addr(trace)) ||
1014 (trace->depth < 0) ||
1015 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1018 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1019 static inline enum print_line_t
1020 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1022 return TRACE_TYPE_UNHANDLED;
1024 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1026 extern struct list_head ftrace_pids;
1028 #ifdef CONFIG_FUNCTION_TRACER
1029 struct ftrace_func_command {
1030 struct list_head list;
1032 int (*func)(struct trace_array *tr,
1033 struct ftrace_hash *hash,
1034 char *func, char *cmd,
1035 char *params, int enable);
1037 extern bool ftrace_filter_param __initdata;
1038 static inline int ftrace_trace_task(struct trace_array *tr)
1040 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
1042 extern int ftrace_is_dead(void);
1043 int ftrace_create_function_files(struct trace_array *tr,
1044 struct dentry *parent);
1045 void ftrace_destroy_function_files(struct trace_array *tr);
1046 void ftrace_init_global_array_ops(struct trace_array *tr);
1047 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1048 void ftrace_reset_array_ops(struct trace_array *tr);
1049 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1050 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1051 struct dentry *d_tracer);
1052 void ftrace_clear_pids(struct trace_array *tr);
1053 int init_function_trace(void);
1054 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1056 static inline int ftrace_trace_task(struct trace_array *tr)
1060 static inline int ftrace_is_dead(void) { return 0; }
1062 ftrace_create_function_files(struct trace_array *tr,
1063 struct dentry *parent)
1067 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1068 static inline __init void
1069 ftrace_init_global_array_ops(struct trace_array *tr) { }
1070 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1071 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1072 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1073 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1074 static inline int init_function_trace(void) { return 0; }
1075 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1076 /* ftace_func_t type is not defined, use macro instead of static inline */
1077 #define ftrace_init_array_ops(tr, func) do { } while (0)
1078 #endif /* CONFIG_FUNCTION_TRACER */
1080 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1082 struct ftrace_probe_ops {
1083 void (*func)(unsigned long ip,
1084 unsigned long parent_ip,
1085 struct trace_array *tr,
1086 struct ftrace_probe_ops *ops,
1088 int (*init)(struct ftrace_probe_ops *ops,
1089 struct trace_array *tr,
1090 unsigned long ip, void *init_data,
1092 void (*free)(struct ftrace_probe_ops *ops,
1093 struct trace_array *tr,
1094 unsigned long ip, void *data);
1095 int (*print)(struct seq_file *m,
1097 struct ftrace_probe_ops *ops,
1101 struct ftrace_func_mapper;
1102 typedef int (*ftrace_mapper_func)(void *data);
1104 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1105 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1107 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1108 unsigned long ip, void *data);
1109 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1111 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1112 ftrace_mapper_func free_func);
1115 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1116 struct ftrace_probe_ops *ops, void *data);
1118 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1119 struct ftrace_probe_ops *ops);
1120 extern void clear_ftrace_function_probes(struct trace_array *tr);
1122 int register_ftrace_command(struct ftrace_func_command *cmd);
1123 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1125 void ftrace_create_filter_files(struct ftrace_ops *ops,
1126 struct dentry *parent);
1127 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1129 struct ftrace_func_command;
1131 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1135 static inline __init int unregister_ftrace_command(char *cmd_name)
1139 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1144 * The ops parameter passed in is usually undefined.
1145 * This must be a macro.
1147 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1148 #define ftrace_destroy_filter_files(ops) do { } while (0)
1149 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1151 bool ftrace_event_is_function(struct trace_event_call *call);
1154 * struct trace_parser - servers for reading the user input separated by spaces
1155 * @cont: set if the input is not complete - no final space char was found
1156 * @buffer: holds the parsed user input
1157 * @idx: user input length
1158 * @size: buffer size
1160 struct trace_parser {
1167 static inline bool trace_parser_loaded(struct trace_parser *parser)
1169 return (parser->idx != 0);
1172 static inline bool trace_parser_cont(struct trace_parser *parser)
1174 return parser->cont;
1177 static inline void trace_parser_clear(struct trace_parser *parser)
1179 parser->cont = false;
1183 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1184 extern void trace_parser_put(struct trace_parser *parser);
1185 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1186 size_t cnt, loff_t *ppos);
1189 * Only create function graph options if function graph is configured.
1191 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1192 # define FGRAPH_FLAGS \
1193 C(DISPLAY_GRAPH, "display-graph"),
1195 # define FGRAPH_FLAGS
1198 #ifdef CONFIG_BRANCH_TRACER
1199 # define BRANCH_FLAGS \
1200 C(BRANCH, "branch"),
1202 # define BRANCH_FLAGS
1205 #ifdef CONFIG_FUNCTION_TRACER
1206 # define FUNCTION_FLAGS \
1207 C(FUNCTION, "function-trace"), \
1208 C(FUNC_FORK, "function-fork"),
1209 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1211 # define FUNCTION_FLAGS
1212 # define FUNCTION_DEFAULT_FLAGS 0UL
1213 # define TRACE_ITER_FUNC_FORK 0UL
1216 #ifdef CONFIG_STACKTRACE
1217 # define STACK_FLAGS \
1218 C(STACKTRACE, "stacktrace"),
1220 # define STACK_FLAGS
1224 * trace_iterator_flags is an enumeration that defines bit
1225 * positions into trace_flags that controls the output.
1227 * NOTE: These bits must match the trace_options array in
1228 * trace.c (this macro guarantees it).
1230 #define TRACE_FLAGS \
1231 C(PRINT_PARENT, "print-parent"), \
1232 C(SYM_OFFSET, "sym-offset"), \
1233 C(SYM_ADDR, "sym-addr"), \
1234 C(VERBOSE, "verbose"), \
1238 C(BLOCK, "block"), \
1239 C(PRINTK, "trace_printk"), \
1240 C(ANNOTATE, "annotate"), \
1241 C(USERSTACKTRACE, "userstacktrace"), \
1242 C(SYM_USEROBJ, "sym-userobj"), \
1243 C(PRINTK_MSGONLY, "printk-msg-only"), \
1244 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1245 C(LATENCY_FMT, "latency-format"), \
1246 C(RECORD_CMD, "record-cmd"), \
1247 C(RECORD_TGID, "record-tgid"), \
1248 C(OVERWRITE, "overwrite"), \
1249 C(STOP_ON_FREE, "disable_on_free"), \
1250 C(IRQ_INFO, "irq-info"), \
1251 C(MARKERS, "markers"), \
1252 C(EVENT_FORK, "event-fork"), \
1259 * By defining C, we can make TRACE_FLAGS a list of bit names
1260 * that will define the bits for the flag masks.
1263 #define C(a, b) TRACE_ITER_##a##_BIT
1265 enum trace_iterator_bits {
1267 /* Make sure we don't go more than we have bits for */
1272 * By redefining C, we can make TRACE_FLAGS a list of masks that
1273 * use the bits as defined above.
1276 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1278 enum trace_iterator_flags { TRACE_FLAGS };
1281 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1282 * control the output of kernel symbols.
1284 #define TRACE_ITER_SYM_MASK \
1285 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1287 extern struct tracer nop_trace;
1289 #ifdef CONFIG_BRANCH_TRACER
1290 extern int enable_branch_tracing(struct trace_array *tr);
1291 extern void disable_branch_tracing(void);
1292 static inline int trace_branch_enable(struct trace_array *tr)
1294 if (tr->trace_flags & TRACE_ITER_BRANCH)
1295 return enable_branch_tracing(tr);
1298 static inline void trace_branch_disable(void)
1300 /* due to races, always disable */
1301 disable_branch_tracing();
1304 static inline int trace_branch_enable(struct trace_array *tr)
1308 static inline void trace_branch_disable(void)
1311 #endif /* CONFIG_BRANCH_TRACER */
1313 /* set ring buffers to default size if not already done so */
1314 int tracing_update_buffers(void);
1316 struct ftrace_event_field {
1317 struct list_head link;
1328 struct event_filter {
1329 struct prog_entry __rcu *prog;
1330 char *filter_string;
1333 struct event_subsystem {
1334 struct list_head list;
1336 struct event_filter *filter;
1340 struct trace_subsystem_dir {
1341 struct list_head list;
1342 struct event_subsystem *subsystem;
1343 struct trace_array *tr;
1344 struct dentry *entry;
1349 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1350 struct ring_buffer *buffer,
1351 struct ring_buffer_event *event);
1353 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1354 struct ring_buffer *buffer,
1355 struct ring_buffer_event *event,
1356 unsigned long flags, int pc,
1357 struct pt_regs *regs);
1359 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1360 struct ring_buffer *buffer,
1361 struct ring_buffer_event *event,
1362 unsigned long flags, int pc)
1364 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1367 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1368 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1369 void trace_buffered_event_disable(void);
1370 void trace_buffered_event_enable(void);
1373 __trace_event_discard_commit(struct ring_buffer *buffer,
1374 struct ring_buffer_event *event)
1376 if (this_cpu_read(trace_buffered_event) == event) {
1377 /* Simply release the temp buffer */
1378 this_cpu_dec(trace_buffered_event_cnt);
1381 ring_buffer_discard_commit(buffer, event);
1385 * Helper function for event_trigger_unlock_commit{_regs}().
1386 * If there are event triggers attached to this event that requires
1387 * filtering against its fields, then they wil be called as the
1388 * entry already holds the field information of the current event.
1390 * It also checks if the event should be discarded or not.
1391 * It is to be discarded if the event is soft disabled and the
1392 * event was only recorded to process triggers, or if the event
1393 * filter is active and this event did not match the filters.
1395 * Returns true if the event is discarded, false otherwise.
1398 __event_trigger_test_discard(struct trace_event_file *file,
1399 struct ring_buffer *buffer,
1400 struct ring_buffer_event *event,
1402 enum event_trigger_type *tt)
1404 unsigned long eflags = file->flags;
1406 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1407 *tt = event_triggers_call(file, entry, event);
1409 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1410 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1411 !filter_match_preds(file->filter, entry))) {
1412 __trace_event_discard_commit(buffer, event);
1420 * event_trigger_unlock_commit - handle triggers and finish event commit
1421 * @file: The file pointer assoctiated to the event
1422 * @buffer: The ring buffer that the event is being written to
1423 * @event: The event meta data in the ring buffer
1424 * @entry: The event itself
1425 * @irq_flags: The state of the interrupts at the start of the event
1426 * @pc: The state of the preempt count at the start of the event.
1428 * This is a helper function to handle triggers that require data
1429 * from the event itself. It also tests the event against filters and
1430 * if the event is soft disabled and should be discarded.
1433 event_trigger_unlock_commit(struct trace_event_file *file,
1434 struct ring_buffer *buffer,
1435 struct ring_buffer_event *event,
1436 void *entry, unsigned long irq_flags, int pc)
1438 enum event_trigger_type tt = ETT_NONE;
1440 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1441 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1444 event_triggers_post_call(file, tt);
1448 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1449 * @file: The file pointer assoctiated to the event
1450 * @buffer: The ring buffer that the event is being written to
1451 * @event: The event meta data in the ring buffer
1452 * @entry: The event itself
1453 * @irq_flags: The state of the interrupts at the start of the event
1454 * @pc: The state of the preempt count at the start of the event.
1456 * This is a helper function to handle triggers that require data
1457 * from the event itself. It also tests the event against filters and
1458 * if the event is soft disabled and should be discarded.
1460 * Same as event_trigger_unlock_commit() but calls
1461 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1464 event_trigger_unlock_commit_regs(struct trace_event_file *file,
1465 struct ring_buffer *buffer,
1466 struct ring_buffer_event *event,
1467 void *entry, unsigned long irq_flags, int pc,
1468 struct pt_regs *regs)
1470 enum event_trigger_type tt = ETT_NONE;
1472 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1473 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1474 irq_flags, pc, regs);
1477 event_triggers_post_call(file, tt);
1480 #define FILTER_PRED_INVALID ((unsigned short)-1)
1481 #define FILTER_PRED_IS_RIGHT (1 << 15)
1482 #define FILTER_PRED_FOLD (1 << 15)
1485 * The max preds is the size of unsigned short with
1486 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1487 * and FOLD flags. The other is reserved.
1489 * 2^14 preds is way more than enough.
1491 #define MAX_FILTER_PRED 16384
1496 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1498 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1510 char pattern[MAX_FILTER_STR_VAL];
1513 regex_match_func match;
1516 struct filter_pred {
1517 filter_pred_fn_t fn;
1520 unsigned short *ops;
1521 struct ftrace_event_field *field;
1527 static inline bool is_string_field(struct ftrace_event_field *field)
1529 return field->filter_type == FILTER_DYN_STRING ||
1530 field->filter_type == FILTER_STATIC_STRING ||
1531 field->filter_type == FILTER_PTR_STRING ||
1532 field->filter_type == FILTER_COMM;
1535 static inline bool is_function_field(struct ftrace_event_field *field)
1537 return field->filter_type == FILTER_TRACE_FN;
1540 extern enum regex_type
1541 filter_parse_regex(char *buff, int len, char **search, int *not);
1542 extern void print_event_filter(struct trace_event_file *file,
1543 struct trace_seq *s);
1544 extern int apply_event_filter(struct trace_event_file *file,
1545 char *filter_string);
1546 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1547 char *filter_string);
1548 extern void print_subsystem_event_filter(struct event_subsystem *system,
1549 struct trace_seq *s);
1550 extern int filter_assign_type(const char *type);
1551 extern int create_event_filter(struct trace_array *tr,
1552 struct trace_event_call *call,
1553 char *filter_str, bool set_str,
1554 struct event_filter **filterp);
1555 extern void free_event_filter(struct event_filter *filter);
1557 struct ftrace_event_field *
1558 trace_find_event_field(struct trace_event_call *call, char *name);
1560 extern void trace_event_enable_cmd_record(bool enable);
1561 extern void trace_event_enable_tgid_record(bool enable);
1563 extern int event_trace_init(void);
1564 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1565 extern int event_trace_del_tracer(struct trace_array *tr);
1567 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1570 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1574 static inline void *event_file_data(struct file *filp)
1576 return READ_ONCE(file_inode(filp)->i_private);
1579 extern struct mutex event_mutex;
1580 extern struct list_head ftrace_events;
1582 extern const struct file_operations event_trigger_fops;
1583 extern const struct file_operations event_hist_fops;
1585 #ifdef CONFIG_HIST_TRIGGERS
1586 extern int register_trigger_hist_cmd(void);
1587 extern int register_trigger_hist_enable_disable_cmds(void);
1589 static inline int register_trigger_hist_cmd(void) { return 0; }
1590 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1593 extern int register_trigger_cmds(void);
1594 extern void clear_event_triggers(struct trace_array *tr);
1596 struct event_trigger_data {
1597 unsigned long count;
1599 struct event_trigger_ops *ops;
1600 struct event_command *cmd_ops;
1601 struct event_filter __rcu *filter;
1606 struct list_head list;
1608 struct list_head named_list;
1609 struct event_trigger_data *named_data;
1613 #define ENABLE_EVENT_STR "enable_event"
1614 #define DISABLE_EVENT_STR "disable_event"
1615 #define ENABLE_HIST_STR "enable_hist"
1616 #define DISABLE_HIST_STR "disable_hist"
1618 struct enable_trigger_data {
1619 struct trace_event_file *file;
1624 extern int event_enable_trigger_print(struct seq_file *m,
1625 struct event_trigger_ops *ops,
1626 struct event_trigger_data *data);
1627 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1628 struct event_trigger_data *data);
1629 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1630 struct trace_event_file *file,
1631 char *glob, char *cmd, char *param);
1632 extern int event_enable_register_trigger(char *glob,
1633 struct event_trigger_ops *ops,
1634 struct event_trigger_data *data,
1635 struct trace_event_file *file);
1636 extern void event_enable_unregister_trigger(char *glob,
1637 struct event_trigger_ops *ops,
1638 struct event_trigger_data *test,
1639 struct trace_event_file *file);
1640 extern void trigger_data_free(struct event_trigger_data *data);
1641 extern int event_trigger_init(struct event_trigger_ops *ops,
1642 struct event_trigger_data *data);
1643 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1644 int trigger_enable);
1645 extern void update_cond_flag(struct trace_event_file *file);
1646 extern int set_trigger_filter(char *filter_str,
1647 struct event_trigger_data *trigger_data,
1648 struct trace_event_file *file);
1649 extern struct event_trigger_data *find_named_trigger(const char *name);
1650 extern bool is_named_trigger(struct event_trigger_data *test);
1651 extern int save_named_trigger(const char *name,
1652 struct event_trigger_data *data);
1653 extern void del_named_trigger(struct event_trigger_data *data);
1654 extern void pause_named_trigger(struct event_trigger_data *data);
1655 extern void unpause_named_trigger(struct event_trigger_data *data);
1656 extern void set_named_trigger_data(struct event_trigger_data *data,
1657 struct event_trigger_data *named_data);
1658 extern struct event_trigger_data *
1659 get_named_trigger_data(struct event_trigger_data *data);
1660 extern int register_event_command(struct event_command *cmd);
1661 extern int unregister_event_command(struct event_command *cmd);
1662 extern int register_trigger_hist_enable_disable_cmds(void);
1665 * struct event_trigger_ops - callbacks for trace event triggers
1667 * The methods in this structure provide per-event trigger hooks for
1668 * various trigger operations.
1670 * All the methods below, except for @init() and @free(), must be
1673 * @func: The trigger 'probe' function called when the triggering
1674 * event occurs. The data passed into this callback is the data
1675 * that was supplied to the event_command @reg() function that
1676 * registered the trigger (see struct event_command) along with
1677 * the trace record, rec.
1679 * @init: An optional initialization function called for the trigger
1680 * when the trigger is registered (via the event_command reg()
1681 * function). This can be used to perform per-trigger
1682 * initialization such as incrementing a per-trigger reference
1683 * count, for instance. This is usually implemented by the
1684 * generic utility function @event_trigger_init() (see
1685 * trace_event_triggers.c).
1687 * @free: An optional de-initialization function called for the
1688 * trigger when the trigger is unregistered (via the
1689 * event_command @reg() function). This can be used to perform
1690 * per-trigger de-initialization such as decrementing a
1691 * per-trigger reference count and freeing corresponding trigger
1692 * data, for instance. This is usually implemented by the
1693 * generic utility function @event_trigger_free() (see
1694 * trace_event_triggers.c).
1696 * @print: The callback function invoked to have the trigger print
1697 * itself. This is usually implemented by a wrapper function
1698 * that calls the generic utility function @event_trigger_print()
1699 * (see trace_event_triggers.c).
1701 struct event_trigger_ops {
1702 void (*func)(struct event_trigger_data *data,
1704 struct ring_buffer_event *rbe);
1705 int (*init)(struct event_trigger_ops *ops,
1706 struct event_trigger_data *data);
1707 void (*free)(struct event_trigger_ops *ops,
1708 struct event_trigger_data *data);
1709 int (*print)(struct seq_file *m,
1710 struct event_trigger_ops *ops,
1711 struct event_trigger_data *data);
1715 * struct event_command - callbacks and data members for event commands
1717 * Event commands are invoked by users by writing the command name
1718 * into the 'trigger' file associated with a trace event. The
1719 * parameters associated with a specific invocation of an event
1720 * command are used to create an event trigger instance, which is
1721 * added to the list of trigger instances associated with that trace
1722 * event. When the event is hit, the set of triggers associated with
1723 * that event is invoked.
1725 * The data members in this structure provide per-event command data
1726 * for various event commands.
1728 * All the data members below, except for @post_trigger, must be set
1729 * for each event command.
1731 * @name: The unique name that identifies the event command. This is
1732 * the name used when setting triggers via trigger files.
1734 * @trigger_type: A unique id that identifies the event command
1735 * 'type'. This value has two purposes, the first to ensure that
1736 * only one trigger of the same type can be set at a given time
1737 * for a particular event e.g. it doesn't make sense to have both
1738 * a traceon and traceoff trigger attached to a single event at
1739 * the same time, so traceon and traceoff have the same type
1740 * though they have different names. The @trigger_type value is
1741 * also used as a bit value for deferring the actual trigger
1742 * action until after the current event is finished. Some
1743 * commands need to do this if they themselves log to the trace
1744 * buffer (see the @post_trigger() member below). @trigger_type
1745 * values are defined by adding new values to the trigger_type
1746 * enum in include/linux/trace_events.h.
1748 * @flags: See the enum event_command_flags below.
1750 * All the methods below, except for @set_filter() and @unreg_all(),
1751 * must be implemented.
1753 * @func: The callback function responsible for parsing and
1754 * registering the trigger written to the 'trigger' file by the
1755 * user. It allocates the trigger instance and registers it with
1756 * the appropriate trace event. It makes use of the other
1757 * event_command callback functions to orchestrate this, and is
1758 * usually implemented by the generic utility function
1759 * @event_trigger_callback() (see trace_event_triggers.c).
1761 * @reg: Adds the trigger to the list of triggers associated with the
1762 * event, and enables the event trigger itself, after
1763 * initializing it (via the event_trigger_ops @init() function).
1764 * This is also where commands can use the @trigger_type value to
1765 * make the decision as to whether or not multiple instances of
1766 * the trigger should be allowed. This is usually implemented by
1767 * the generic utility function @register_trigger() (see
1768 * trace_event_triggers.c).
1770 * @unreg: Removes the trigger from the list of triggers associated
1771 * with the event, and disables the event trigger itself, after
1772 * initializing it (via the event_trigger_ops @free() function).
1773 * This is usually implemented by the generic utility function
1774 * @unregister_trigger() (see trace_event_triggers.c).
1776 * @unreg_all: An optional function called to remove all the triggers
1777 * from the list of triggers associated with the event. Called
1778 * when a trigger file is opened in truncate mode.
1780 * @set_filter: An optional function called to parse and set a filter
1781 * for the trigger. If no @set_filter() method is set for the
1782 * event command, filters set by the user for the command will be
1783 * ignored. This is usually implemented by the generic utility
1784 * function @set_trigger_filter() (see trace_event_triggers.c).
1786 * @get_trigger_ops: The callback function invoked to retrieve the
1787 * event_trigger_ops implementation associated with the command.
1789 struct event_command {
1790 struct list_head list;
1792 enum event_trigger_type trigger_type;
1794 int (*func)(struct event_command *cmd_ops,
1795 struct trace_event_file *file,
1796 char *glob, char *cmd, char *params);
1797 int (*reg)(char *glob,
1798 struct event_trigger_ops *ops,
1799 struct event_trigger_data *data,
1800 struct trace_event_file *file);
1801 void (*unreg)(char *glob,
1802 struct event_trigger_ops *ops,
1803 struct event_trigger_data *data,
1804 struct trace_event_file *file);
1805 void (*unreg_all)(struct trace_event_file *file);
1806 int (*set_filter)(char *filter_str,
1807 struct event_trigger_data *data,
1808 struct trace_event_file *file);
1809 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1813 * enum event_command_flags - flags for struct event_command
1815 * @POST_TRIGGER: A flag that says whether or not this command needs
1816 * to have its action delayed until after the current event has
1817 * been closed. Some triggers need to avoid being invoked while
1818 * an event is currently in the process of being logged, since
1819 * the trigger may itself log data into the trace buffer. Thus
1820 * we make sure the current event is committed before invoking
1821 * those triggers. To do that, the trigger invocation is split
1822 * in two - the first part checks the filter using the current
1823 * trace record; if a command has the @post_trigger flag set, it
1824 * sets a bit for itself in the return value, otherwise it
1825 * directly invokes the trigger. Once all commands have been
1826 * either invoked or set their return flag, the current record is
1827 * either committed or discarded. At that point, if any commands
1828 * have deferred their triggers, those commands are finally
1829 * invoked following the close of the current event. In other
1830 * words, if the event_trigger_ops @func() probe implementation
1831 * itself logs to the trace buffer, this flag should be set,
1832 * otherwise it can be left unspecified.
1834 * @NEEDS_REC: A flag that says whether or not this command needs
1835 * access to the trace record in order to perform its function,
1836 * regardless of whether or not it has a filter associated with
1837 * it (filters make a trigger require access to the trace record
1838 * but are not always present).
1840 enum event_command_flags {
1841 EVENT_CMD_FL_POST_TRIGGER = 1,
1842 EVENT_CMD_FL_NEEDS_REC = 2,
1845 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1847 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1850 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1852 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1855 extern int trace_event_enable_disable(struct trace_event_file *file,
1856 int enable, int soft_disable);
1857 extern int tracing_alloc_snapshot(void);
1858 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1859 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1861 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1862 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1864 extern const char *__start___trace_bprintk_fmt[];
1865 extern const char *__stop___trace_bprintk_fmt[];
1867 extern const char *__start___tracepoint_str[];
1868 extern const char *__stop___tracepoint_str[];
1870 void trace_printk_control(bool enabled);
1871 void trace_printk_init_buffers(void);
1872 void trace_printk_start_comm(void);
1873 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1874 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1876 #define MAX_EVENT_NAME_LEN 64
1878 extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1879 extern ssize_t trace_parse_run_command(struct file *file,
1880 const char __user *buffer, size_t count, loff_t *ppos,
1881 int (*createfn)(int, char**));
1883 extern unsigned int err_pos(char *cmd, const char *str);
1884 extern void tracing_log_err(struct trace_array *tr,
1885 const char *loc, const char *cmd,
1886 const char **errs, u8 type, u8 pos);
1889 * Normal trace_printk() and friends allocates special buffers
1890 * to do the manipulation, as well as saves the print formats
1891 * into sections to display. But the trace infrastructure wants
1892 * to use these without the added overhead at the price of being
1893 * a bit slower (used mainly for warnings, where we don't care
1894 * about performance). The internal_trace_puts() is for such
1897 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1900 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1901 extern struct trace_event_call \
1902 __aligned(4) event_##call;
1903 #undef FTRACE_ENTRY_DUP
1904 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1905 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1907 #undef FTRACE_ENTRY_PACKED
1908 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1909 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1912 #include "trace_entries.h"
1914 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1915 int perf_ftrace_event_register(struct trace_event_call *call,
1916 enum trace_reg type, void *data);
1918 #define perf_ftrace_event_register NULL
1921 #ifdef CONFIG_FTRACE_SYSCALLS
1922 void init_ftrace_syscalls(void);
1923 const char *get_syscall_name(int syscall);
1925 static inline void init_ftrace_syscalls(void) { }
1926 static inline const char *get_syscall_name(int syscall)
1932 #ifdef CONFIG_EVENT_TRACING
1933 void trace_event_init(void);
1934 void trace_event_eval_update(struct trace_eval_map **map, int len);
1936 static inline void __init trace_event_init(void) { }
1937 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1940 #ifdef CONFIG_TRACER_SNAPSHOT
1941 void tracing_snapshot_instance(struct trace_array *tr);
1942 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1944 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1945 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1951 #ifdef CONFIG_PREEMPT_TRACER
1952 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1953 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1955 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1956 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1958 #ifdef CONFIG_IRQSOFF_TRACER
1959 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1960 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1962 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1963 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1966 extern struct trace_iterator *tracepoint_print_iter;
1969 * Reset the state of the trace_iterator so that it can read consumed data.
1970 * Normally, the trace_iterator is used for reading the data when it is not
1971 * consumed, and must retain state.
1973 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1975 const size_t offset = offsetof(struct trace_iterator, seq);
1978 * Keep gcc from complaining about overwriting more than just one
1979 * member in the structure.
1981 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1986 #endif /* _LINUX_KERNEL_TRACE_H */