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/trace_seq.h>
19 #include <linux/glob.h>
21 #ifdef CONFIG_FTRACE_SYSCALLS
22 #include <asm/unistd.h> /* For NR_SYSCALLS */
23 #include <asm/syscall.h> /* some archs define it here */
27 __TRACE_FIRST_TYPE = 0,
51 #define __field(type, item) type item;
54 #define __field_struct(type, item) __field(type, item)
57 #define __field_desc(type, container, item)
60 #define __array(type, item, size) type item[size];
63 #define __array_desc(type, container, item, size)
65 #undef __dynamic_array
66 #define __dynamic_array(type, item) type item[];
69 #define F_STRUCT(args...) args
72 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
73 struct struct_name { \
74 struct trace_entry ent; \
78 #undef FTRACE_ENTRY_DUP
79 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
81 #undef FTRACE_ENTRY_REG
82 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
84 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
87 #undef FTRACE_ENTRY_PACKED
88 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \
90 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
93 #include "trace_entries.h"
96 * syscalls are special, and need special handling, this is why
97 * they are not included in trace_entries.h
99 struct syscall_trace_enter {
100 struct trace_entry ent;
102 unsigned long args[];
105 struct syscall_trace_exit {
106 struct trace_entry ent;
111 struct kprobe_trace_entry_head {
112 struct trace_entry ent;
116 struct kretprobe_trace_entry_head {
117 struct trace_entry ent;
119 unsigned long ret_ip;
123 * trace_flag_type is an enumeration that holds different
124 * states when a trace occurs. These are:
125 * IRQS_OFF - interrupts were disabled
126 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
127 * NEED_RESCHED - reschedule is requested
128 * HARDIRQ - inside an interrupt handler
129 * SOFTIRQ - inside a softirq handler
131 enum trace_flag_type {
132 TRACE_FLAG_IRQS_OFF = 0x01,
133 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
134 TRACE_FLAG_NEED_RESCHED = 0x04,
135 TRACE_FLAG_HARDIRQ = 0x08,
136 TRACE_FLAG_SOFTIRQ = 0x10,
137 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
138 TRACE_FLAG_NMI = 0x40,
141 #define TRACE_BUF_SIZE 1024
146 * The CPU trace array - it consists of thousands of trace entries
147 * plus some other descriptor data: (for example which task started
150 struct trace_array_cpu {
152 void *buffer_page; /* ring buffer spare */
154 unsigned long entries;
155 unsigned long saved_latency;
156 unsigned long critical_start;
157 unsigned long critical_end;
158 unsigned long critical_sequence;
160 unsigned long policy;
161 unsigned long rt_priority;
162 unsigned long skipped_entries;
163 u64 preempt_timestamp;
166 char comm[TASK_COMM_LEN];
169 #ifdef CONFIG_FUNCTION_TRACER
170 bool ftrace_ignore_pid;
175 struct trace_option_dentry;
177 struct trace_buffer {
178 struct trace_array *tr;
179 struct ring_buffer *buffer;
180 struct trace_array_cpu __percpu *data;
185 #define TRACE_FLAGS_MAX_SIZE 32
187 struct trace_options {
188 struct tracer *tracer;
189 struct trace_option_dentry *topts;
192 struct trace_pid_list {
198 * The trace array - an array of per-CPU trace arrays. This is the
199 * highest level data structure that individual tracers deal with.
200 * They have on/off state as well:
203 struct list_head list;
205 struct trace_buffer trace_buffer;
206 #ifdef CONFIG_TRACER_MAX_TRACE
208 * The max_buffer is used to snapshot the trace when a maximum
209 * latency is reached, or when the user initiates a snapshot.
210 * Some tracers will use this to store a maximum trace while
211 * it continues examining live traces.
213 * The buffers for the max_buffer are set up the same as the trace_buffer
214 * When a snapshot is taken, the buffer of the max_buffer is swapped
215 * with the buffer of the trace_buffer and the buffers are reset for
216 * the trace_buffer so the tracing can continue.
218 struct trace_buffer max_buffer;
219 bool allocated_snapshot;
221 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
222 unsigned long max_latency;
224 struct trace_pid_list __rcu *filtered_pids;
226 * max_lock is used to protect the swapping of buffers
227 * when taking a max snapshot. The buffers themselves are
228 * protected by per_cpu spinlocks. But the action of the swap
229 * needs its own lock.
231 * This is defined as a arch_spinlock_t in order to help
232 * with performance when lockdep debugging is enabled.
234 * It is also used in other places outside the update_max_tr
235 * so it needs to be defined outside of the
236 * CONFIG_TRACER_MAX_TRACE.
238 arch_spinlock_t max_lock;
240 #ifdef CONFIG_FTRACE_SYSCALLS
241 int sys_refcount_enter;
242 int sys_refcount_exit;
243 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
244 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
251 struct tracer *current_trace;
252 unsigned int trace_flags;
253 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
255 raw_spinlock_t start_lock;
257 struct dentry *options;
258 struct dentry *percpu_dir;
259 struct dentry *event_dir;
260 struct trace_options *topts;
261 struct list_head systems;
262 struct list_head events;
263 struct trace_event_file *trace_marker_file;
264 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
266 #ifdef CONFIG_FUNCTION_TRACER
267 struct ftrace_ops *ops;
268 struct trace_pid_list __rcu *function_pids;
269 #ifdef CONFIG_DYNAMIC_FTRACE
270 /* All of these are protected by the ftrace_lock */
271 struct list_head func_probes;
272 struct list_head mod_trace;
273 struct list_head mod_notrace;
275 /* function tracing enabled */
276 int function_enabled;
278 int time_stamp_abs_ref;
279 struct list_head hist_vars;
283 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
286 extern struct list_head ftrace_trace_arrays;
288 extern struct mutex trace_types_lock;
290 extern int trace_array_get(struct trace_array *tr);
291 extern void trace_array_put(struct trace_array *tr);
293 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
294 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
296 extern bool trace_clock_in_ns(struct trace_array *tr);
299 * The global tracer (top) should be the first trace array added,
300 * but we check the flag anyway.
302 static inline struct trace_array *top_trace_array(void)
304 struct trace_array *tr;
306 if (list_empty(&ftrace_trace_arrays))
309 tr = list_entry(ftrace_trace_arrays.prev,
311 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
315 #define FTRACE_CMP_TYPE(var, type) \
316 __builtin_types_compatible_p(typeof(var), type *)
319 #define IF_ASSIGN(var, entry, etype, id) \
320 if (FTRACE_CMP_TYPE(var, etype)) { \
321 var = (typeof(var))(entry); \
322 WARN_ON(id && (entry)->type != id); \
326 /* Will cause compile errors if type is not found. */
327 extern void __ftrace_bad_type(void);
330 * The trace_assign_type is a verifier that the entry type is
331 * the same as the type being assigned. To add new types simply
332 * add a line with the following format:
334 * IF_ASSIGN(var, ent, type, id);
336 * Where "type" is the trace type that includes the trace_entry
337 * as the "ent" item. And "id" is the trace identifier that is
338 * used in the trace_type enum.
340 * If the type can have more than one id, then use zero.
342 #define trace_assign_type(var, ent) \
344 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
345 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
346 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
347 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
348 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
349 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
350 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
351 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
352 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
353 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
355 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
357 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
358 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
360 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
362 __ftrace_bad_type(); \
366 * An option specific to a tracer. This is a boolean value.
367 * The bit is the bit index that sets its value on the
368 * flags value in struct tracer_flags.
371 const char *name; /* Will appear on the trace_options file */
372 u32 bit; /* Mask assigned in val field in tracer_flags */
376 * The set of specific options for a tracer. Your tracer
377 * have to set the initial value of the flags val.
379 struct tracer_flags {
381 struct tracer_opt *opts;
382 struct tracer *trace;
385 /* Makes more easy to define a tracer opt */
386 #define TRACER_OPT(s, b) .name = #s, .bit = b
389 struct trace_option_dentry {
390 struct tracer_opt *opt;
391 struct tracer_flags *flags;
392 struct trace_array *tr;
393 struct dentry *entry;
397 * struct tracer - a specific tracer and its callbacks to interact with tracefs
398 * @name: the name chosen to select it on the available_tracers file
399 * @init: called when one switches to this tracer (echo name > current_tracer)
400 * @reset: called when one switches to another tracer
401 * @start: called when tracing is unpaused (echo 1 > tracing_on)
402 * @stop: called when tracing is paused (echo 0 > tracing_on)
403 * @update_thresh: called when tracing_thresh is updated
404 * @open: called when the trace file is opened
405 * @pipe_open: called when the trace_pipe file is opened
406 * @close: called when the trace file is released
407 * @pipe_close: called when the trace_pipe file is released
408 * @read: override the default read callback on trace_pipe
409 * @splice_read: override the default splice_read callback on trace_pipe
410 * @selftest: selftest to run on boot (see trace_selftest.c)
411 * @print_headers: override the first lines that describe your columns
412 * @print_line: callback that prints a trace
413 * @set_flag: signals one of your private flags changed (trace_options file)
414 * @flags: your private flags
418 int (*init)(struct trace_array *tr);
419 void (*reset)(struct trace_array *tr);
420 void (*start)(struct trace_array *tr);
421 void (*stop)(struct trace_array *tr);
422 int (*update_thresh)(struct trace_array *tr);
423 void (*open)(struct trace_iterator *iter);
424 void (*pipe_open)(struct trace_iterator *iter);
425 void (*close)(struct trace_iterator *iter);
426 void (*pipe_close)(struct trace_iterator *iter);
427 ssize_t (*read)(struct trace_iterator *iter,
428 struct file *filp, char __user *ubuf,
429 size_t cnt, loff_t *ppos);
430 ssize_t (*splice_read)(struct trace_iterator *iter,
433 struct pipe_inode_info *pipe,
436 #ifdef CONFIG_FTRACE_STARTUP_TEST
437 int (*selftest)(struct tracer *trace,
438 struct trace_array *tr);
440 void (*print_header)(struct seq_file *m);
441 enum print_line_t (*print_line)(struct trace_iterator *iter);
442 /* If you handled the flag setting, return 0 */
443 int (*set_flag)(struct trace_array *tr,
444 u32 old_flags, u32 bit, int set);
445 /* Return 0 if OK with change, else return non-zero */
446 int (*flag_changed)(struct trace_array *tr,
449 struct tracer_flags *flags;
453 bool allow_instances;
454 #ifdef CONFIG_TRACER_MAX_TRACE
457 /* True if tracer cannot be enabled in kernel param */
462 /* Only current can touch trace_recursion */
465 * For function tracing recursion:
466 * The order of these bits are important.
468 * When function tracing occurs, the following steps are made:
469 * If arch does not support a ftrace feature:
470 * call internal function (uses INTERNAL bits) which calls...
471 * If callback is registered to the "global" list, the list
472 * function is called and recursion checks the GLOBAL bits.
473 * then this function calls...
474 * The function callback, which can use the FTRACE bits to
475 * check for recursion.
477 * Now if the arch does not suppport a feature, and it calls
478 * the global list function which calls the ftrace callback
479 * all three of these steps will do a recursion protection.
480 * There's no reason to do one if the previous caller already
481 * did. The recursion that we are protecting against will
482 * go through the same steps again.
484 * To prevent the multiple recursion checks, if a recursion
485 * bit is set that is higher than the MAX bit of the current
486 * check, then we know that the check was made by the previous
487 * caller, and we can skip the current check.
491 TRACE_BUFFER_NMI_BIT,
492 TRACE_BUFFER_IRQ_BIT,
493 TRACE_BUFFER_SIRQ_BIT,
495 /* Start of function recursion bits */
497 TRACE_FTRACE_NMI_BIT,
498 TRACE_FTRACE_IRQ_BIT,
499 TRACE_FTRACE_SIRQ_BIT,
501 /* INTERNAL_BITs must be greater than FTRACE_BITs */
503 TRACE_INTERNAL_NMI_BIT,
504 TRACE_INTERNAL_IRQ_BIT,
505 TRACE_INTERNAL_SIRQ_BIT,
509 * Abuse of the trace_recursion.
510 * As we need a way to maintain state if we are tracing the function
511 * graph in irq because we want to trace a particular function that
512 * was called in irq context but we have irq tracing off. Since this
513 * can only be modified by current, we can reuse trace_recursion.
517 /* Set if the function is in the set_graph_function file */
521 * In the very unlikely case that an interrupt came in
522 * at a start of graph tracing, and we want to trace
523 * the function in that interrupt, the depth can be greater
524 * than zero, because of the preempted start of a previous
525 * trace. In an even more unlikely case, depth could be 2
526 * if a softirq interrupted the start of graph tracing,
527 * followed by an interrupt preempting a start of graph
528 * tracing in the softirq, and depth can even be 3
529 * if an NMI came in at the start of an interrupt function
530 * that preempted a softirq start of a function that
531 * preempted normal context!!!! Luckily, it can't be
532 * greater than 3, so the next two bits are a mask
533 * of what the depth is when we set TRACE_GRAPH_BIT
536 TRACE_GRAPH_DEPTH_START_BIT,
537 TRACE_GRAPH_DEPTH_END_BIT,
540 * To implement set_graph_notrace, if this bit is set, we ignore
541 * function graph tracing of called functions, until the return
542 * function is called to clear it.
544 TRACE_GRAPH_NOTRACE_BIT,
547 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
548 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
549 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
551 #define trace_recursion_depth() \
552 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
553 #define trace_recursion_set_depth(depth) \
555 current->trace_recursion &= \
556 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
557 current->trace_recursion |= \
558 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
561 #define TRACE_CONTEXT_BITS 4
563 #define TRACE_FTRACE_START TRACE_FTRACE_BIT
564 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
566 #define TRACE_LIST_START TRACE_INTERNAL_BIT
567 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
569 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX
571 static __always_inline int trace_get_context_bit(void)
575 if (in_interrupt()) {
589 static __always_inline int trace_test_and_set_recursion(int start, int max)
591 unsigned int val = current->trace_recursion;
594 /* A previous recursion check was made */
595 if ((val & TRACE_CONTEXT_MASK) > max)
598 bit = trace_get_context_bit() + start;
599 if (unlikely(val & (1 << bit)))
603 current->trace_recursion = val;
609 static __always_inline void trace_clear_recursion(int bit)
611 unsigned int val = current->trace_recursion;
620 current->trace_recursion = val;
623 static inline struct ring_buffer_iter *
624 trace_buffer_iter(struct trace_iterator *iter, int cpu)
626 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
629 int tracer_init(struct tracer *t, struct trace_array *tr);
630 int tracing_is_enabled(void);
631 void tracing_reset(struct trace_buffer *buf, int cpu);
632 void tracing_reset_online_cpus(struct trace_buffer *buf);
633 void tracing_reset_current(int cpu);
634 void tracing_reset_all_online_cpus(void);
635 int tracing_open_generic(struct inode *inode, struct file *filp);
636 bool tracing_is_disabled(void);
637 bool tracer_tracing_is_on(struct trace_array *tr);
638 void tracer_tracing_on(struct trace_array *tr);
639 void tracer_tracing_off(struct trace_array *tr);
640 struct dentry *trace_create_file(const char *name,
642 struct dentry *parent,
644 const struct file_operations *fops);
646 struct dentry *tracing_init_dentry(void);
648 struct ring_buffer_event;
650 struct ring_buffer_event *
651 trace_buffer_lock_reserve(struct ring_buffer *buffer,
657 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
658 struct trace_array_cpu *data);
660 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
661 int *ent_cpu, u64 *ent_ts);
663 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
664 struct ring_buffer_event *event);
666 int trace_empty(struct trace_iterator *iter);
668 void *trace_find_next_entry_inc(struct trace_iterator *iter);
670 void trace_init_global_iter(struct trace_iterator *iter);
672 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
674 void trace_function(struct trace_array *tr,
676 unsigned long parent_ip,
677 unsigned long flags, int pc);
678 void trace_graph_function(struct trace_array *tr,
680 unsigned long parent_ip,
681 unsigned long flags, int pc);
682 void trace_latency_header(struct seq_file *m);
683 void trace_default_header(struct seq_file *m);
684 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
685 int trace_empty(struct trace_iterator *iter);
687 void trace_graph_return(struct ftrace_graph_ret *trace);
688 int trace_graph_entry(struct ftrace_graph_ent *trace);
689 void set_graph_array(struct trace_array *tr);
691 void tracing_start_cmdline_record(void);
692 void tracing_stop_cmdline_record(void);
693 void tracing_start_tgid_record(void);
694 void tracing_stop_tgid_record(void);
696 int register_tracer(struct tracer *type);
697 int is_tracing_stopped(void);
699 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
701 extern cpumask_var_t __read_mostly tracing_buffer_mask;
703 #define for_each_tracing_cpu(cpu) \
704 for_each_cpu(cpu, tracing_buffer_mask)
706 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
708 extern unsigned long tracing_thresh;
714 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
716 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
717 struct task_struct *task);
718 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
719 struct task_struct *self,
720 struct task_struct *task);
721 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
722 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
723 int trace_pid_show(struct seq_file *m, void *v);
724 void trace_free_pid_list(struct trace_pid_list *pid_list);
725 int trace_pid_write(struct trace_pid_list *filtered_pids,
726 struct trace_pid_list **new_pid_list,
727 const char __user *ubuf, size_t cnt);
729 #ifdef CONFIG_TRACER_MAX_TRACE
730 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
731 void update_max_tr_single(struct trace_array *tr,
732 struct task_struct *tsk, int cpu);
733 #endif /* CONFIG_TRACER_MAX_TRACE */
735 #ifdef CONFIG_STACKTRACE
736 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
739 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
742 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
743 unsigned long flags, int pc)
747 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
751 #endif /* CONFIG_STACKTRACE */
753 extern u64 ftrace_now(int cpu);
755 extern void trace_find_cmdline(int pid, char comm[]);
756 extern int trace_find_tgid(int pid);
757 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
759 #ifdef CONFIG_DYNAMIC_FTRACE
760 extern unsigned long ftrace_update_tot_cnt;
761 void ftrace_init_trace_array(struct trace_array *tr);
763 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
765 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
766 extern int DYN_FTRACE_TEST_NAME(void);
767 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
768 extern int DYN_FTRACE_TEST_NAME2(void);
770 extern bool ring_buffer_expanded;
771 extern bool tracing_selftest_disabled;
773 #ifdef CONFIG_FTRACE_STARTUP_TEST
774 extern int trace_selftest_startup_function(struct tracer *trace,
775 struct trace_array *tr);
776 extern int trace_selftest_startup_function_graph(struct tracer *trace,
777 struct trace_array *tr);
778 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
779 struct trace_array *tr);
780 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
781 struct trace_array *tr);
782 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
783 struct trace_array *tr);
784 extern int trace_selftest_startup_wakeup(struct tracer *trace,
785 struct trace_array *tr);
786 extern int trace_selftest_startup_nop(struct tracer *trace,
787 struct trace_array *tr);
788 extern int trace_selftest_startup_branch(struct tracer *trace,
789 struct trace_array *tr);
791 * Tracer data references selftest functions that only occur
792 * on boot up. These can be __init functions. Thus, when selftests
793 * are enabled, then the tracers need to reference __init functions.
795 #define __tracer_data __refdata
797 /* Tracers are seldom changed. Optimize when selftests are disabled. */
798 #define __tracer_data __read_mostly
799 #endif /* CONFIG_FTRACE_STARTUP_TEST */
801 extern void *head_page(struct trace_array_cpu *data);
802 extern unsigned long long ns2usecs(u64 nsec);
804 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
806 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
808 trace_array_vprintk(struct trace_array *tr,
809 unsigned long ip, const char *fmt, va_list args);
810 int trace_array_printk(struct trace_array *tr,
811 unsigned long ip, const char *fmt, ...);
812 int trace_array_printk_buf(struct ring_buffer *buffer,
813 unsigned long ip, const char *fmt, ...);
814 void trace_printk_seq(struct trace_seq *s);
815 enum print_line_t print_trace_line(struct trace_iterator *iter);
817 extern char trace_find_mark(unsigned long long duration);
821 struct ftrace_mod_load {
822 struct list_head list;
829 FTRACE_HASH_FL_MOD = (1 << 0),
833 unsigned long size_bits;
834 struct hlist_head *buckets;
840 struct ftrace_func_entry *
841 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
843 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
845 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
848 /* Standard output formatting function used for function return traces */
849 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
852 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
853 #define TRACE_GRAPH_PRINT_CPU 0x2
854 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
855 #define TRACE_GRAPH_PRINT_PROC 0x8
856 #define TRACE_GRAPH_PRINT_DURATION 0x10
857 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
858 #define TRACE_GRAPH_PRINT_IRQS 0x40
859 #define TRACE_GRAPH_PRINT_TAIL 0x80
860 #define TRACE_GRAPH_SLEEP_TIME 0x100
861 #define TRACE_GRAPH_GRAPH_TIME 0x200
862 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
863 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
865 extern void ftrace_graph_sleep_time_control(bool enable);
867 #ifdef CONFIG_FUNCTION_PROFILER
868 extern void ftrace_graph_graph_time_control(bool enable);
870 static inline void ftrace_graph_graph_time_control(bool enable) { }
873 extern enum print_line_t
874 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
875 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
877 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
878 extern void graph_trace_open(struct trace_iterator *iter);
879 extern void graph_trace_close(struct trace_iterator *iter);
880 extern int __trace_graph_entry(struct trace_array *tr,
881 struct ftrace_graph_ent *trace,
882 unsigned long flags, int pc);
883 extern void __trace_graph_return(struct trace_array *tr,
884 struct ftrace_graph_ret *trace,
885 unsigned long flags, int pc);
887 #ifdef CONFIG_DYNAMIC_FTRACE
888 extern struct ftrace_hash *ftrace_graph_hash;
889 extern struct ftrace_hash *ftrace_graph_notrace_hash;
891 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
893 unsigned long addr = trace->func;
896 preempt_disable_notrace();
898 if (ftrace_hash_empty(ftrace_graph_hash)) {
903 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
906 * This needs to be cleared on the return functions
907 * when the depth is zero.
909 trace_recursion_set(TRACE_GRAPH_BIT);
910 trace_recursion_set_depth(trace->depth);
913 * If no irqs are to be traced, but a set_graph_function
914 * is set, and called by an interrupt handler, we still
918 trace_recursion_set(TRACE_IRQ_BIT);
920 trace_recursion_clear(TRACE_IRQ_BIT);
925 preempt_enable_notrace();
929 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
931 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
932 trace->depth == trace_recursion_depth())
933 trace_recursion_clear(TRACE_GRAPH_BIT);
936 static inline int ftrace_graph_notrace_addr(unsigned long addr)
940 preempt_disable_notrace();
942 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
945 preempt_enable_notrace();
949 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
954 static inline int ftrace_graph_notrace_addr(unsigned long addr)
958 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
960 #endif /* CONFIG_DYNAMIC_FTRACE */
962 extern unsigned int fgraph_max_depth;
964 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
966 /* trace it when it is-nested-in or is a function enabled. */
967 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
968 ftrace_graph_addr(trace)) ||
969 (trace->depth < 0) ||
970 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
973 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
974 static inline enum print_line_t
975 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
977 return TRACE_TYPE_UNHANDLED;
979 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
981 extern struct list_head ftrace_pids;
983 #ifdef CONFIG_FUNCTION_TRACER
984 struct ftrace_func_command {
985 struct list_head list;
987 int (*func)(struct trace_array *tr,
988 struct ftrace_hash *hash,
989 char *func, char *cmd,
990 char *params, int enable);
992 extern bool ftrace_filter_param __initdata;
993 static inline int ftrace_trace_task(struct trace_array *tr)
995 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
997 extern int ftrace_is_dead(void);
998 int ftrace_create_function_files(struct trace_array *tr,
999 struct dentry *parent);
1000 void ftrace_destroy_function_files(struct trace_array *tr);
1001 void ftrace_init_global_array_ops(struct trace_array *tr);
1002 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1003 void ftrace_reset_array_ops(struct trace_array *tr);
1004 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1005 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1006 struct dentry *d_tracer);
1007 void ftrace_clear_pids(struct trace_array *tr);
1008 int init_function_trace(void);
1009 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1011 static inline int ftrace_trace_task(struct trace_array *tr)
1015 static inline int ftrace_is_dead(void) { return 0; }
1017 ftrace_create_function_files(struct trace_array *tr,
1018 struct dentry *parent)
1022 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1023 static inline __init void
1024 ftrace_init_global_array_ops(struct trace_array *tr) { }
1025 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1026 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1027 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1028 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1029 static inline int init_function_trace(void) { return 0; }
1030 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1031 /* ftace_func_t type is not defined, use macro instead of static inline */
1032 #define ftrace_init_array_ops(tr, func) do { } while (0)
1033 #endif /* CONFIG_FUNCTION_TRACER */
1035 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1037 struct ftrace_probe_ops {
1038 void (*func)(unsigned long ip,
1039 unsigned long parent_ip,
1040 struct trace_array *tr,
1041 struct ftrace_probe_ops *ops,
1043 int (*init)(struct ftrace_probe_ops *ops,
1044 struct trace_array *tr,
1045 unsigned long ip, void *init_data,
1047 void (*free)(struct ftrace_probe_ops *ops,
1048 struct trace_array *tr,
1049 unsigned long ip, void *data);
1050 int (*print)(struct seq_file *m,
1052 struct ftrace_probe_ops *ops,
1056 struct ftrace_func_mapper;
1057 typedef int (*ftrace_mapper_func)(void *data);
1059 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1060 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1062 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1063 unsigned long ip, void *data);
1064 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1066 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1067 ftrace_mapper_func free_func);
1070 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1071 struct ftrace_probe_ops *ops, void *data);
1073 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1074 struct ftrace_probe_ops *ops);
1075 extern void clear_ftrace_function_probes(struct trace_array *tr);
1077 int register_ftrace_command(struct ftrace_func_command *cmd);
1078 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1080 void ftrace_create_filter_files(struct ftrace_ops *ops,
1081 struct dentry *parent);
1082 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1084 struct ftrace_func_command;
1086 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1090 static inline __init int unregister_ftrace_command(char *cmd_name)
1094 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1099 * The ops parameter passed in is usually undefined.
1100 * This must be a macro.
1102 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1103 #define ftrace_destroy_filter_files(ops) do { } while (0)
1104 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1106 bool ftrace_event_is_function(struct trace_event_call *call);
1109 * struct trace_parser - servers for reading the user input separated by spaces
1110 * @cont: set if the input is not complete - no final space char was found
1111 * @buffer: holds the parsed user input
1112 * @idx: user input length
1113 * @size: buffer size
1115 struct trace_parser {
1122 static inline bool trace_parser_loaded(struct trace_parser *parser)
1124 return (parser->idx != 0);
1127 static inline bool trace_parser_cont(struct trace_parser *parser)
1129 return parser->cont;
1132 static inline void trace_parser_clear(struct trace_parser *parser)
1134 parser->cont = false;
1138 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1139 extern void trace_parser_put(struct trace_parser *parser);
1140 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1141 size_t cnt, loff_t *ppos);
1144 * Only create function graph options if function graph is configured.
1146 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1147 # define FGRAPH_FLAGS \
1148 C(DISPLAY_GRAPH, "display-graph"),
1150 # define FGRAPH_FLAGS
1153 #ifdef CONFIG_BRANCH_TRACER
1154 # define BRANCH_FLAGS \
1155 C(BRANCH, "branch"),
1157 # define BRANCH_FLAGS
1160 #ifdef CONFIG_FUNCTION_TRACER
1161 # define FUNCTION_FLAGS \
1162 C(FUNCTION, "function-trace"), \
1163 C(FUNC_FORK, "function-fork"),
1164 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1166 # define FUNCTION_FLAGS
1167 # define FUNCTION_DEFAULT_FLAGS 0UL
1168 # define TRACE_ITER_FUNC_FORK 0UL
1171 #ifdef CONFIG_STACKTRACE
1172 # define STACK_FLAGS \
1173 C(STACKTRACE, "stacktrace"),
1175 # define STACK_FLAGS
1179 * trace_iterator_flags is an enumeration that defines bit
1180 * positions into trace_flags that controls the output.
1182 * NOTE: These bits must match the trace_options array in
1183 * trace.c (this macro guarantees it).
1185 #define TRACE_FLAGS \
1186 C(PRINT_PARENT, "print-parent"), \
1187 C(SYM_OFFSET, "sym-offset"), \
1188 C(SYM_ADDR, "sym-addr"), \
1189 C(VERBOSE, "verbose"), \
1193 C(BLOCK, "block"), \
1194 C(PRINTK, "trace_printk"), \
1195 C(ANNOTATE, "annotate"), \
1196 C(USERSTACKTRACE, "userstacktrace"), \
1197 C(SYM_USEROBJ, "sym-userobj"), \
1198 C(PRINTK_MSGONLY, "printk-msg-only"), \
1199 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1200 C(LATENCY_FMT, "latency-format"), \
1201 C(RECORD_CMD, "record-cmd"), \
1202 C(RECORD_TGID, "record-tgid"), \
1203 C(OVERWRITE, "overwrite"), \
1204 C(STOP_ON_FREE, "disable_on_free"), \
1205 C(IRQ_INFO, "irq-info"), \
1206 C(MARKERS, "markers"), \
1207 C(EVENT_FORK, "event-fork"), \
1214 * By defining C, we can make TRACE_FLAGS a list of bit names
1215 * that will define the bits for the flag masks.
1218 #define C(a, b) TRACE_ITER_##a##_BIT
1220 enum trace_iterator_bits {
1222 /* Make sure we don't go more than we have bits for */
1227 * By redefining C, we can make TRACE_FLAGS a list of masks that
1228 * use the bits as defined above.
1231 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1233 enum trace_iterator_flags { TRACE_FLAGS };
1236 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1237 * control the output of kernel symbols.
1239 #define TRACE_ITER_SYM_MASK \
1240 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1242 extern struct tracer nop_trace;
1244 #ifdef CONFIG_BRANCH_TRACER
1245 extern int enable_branch_tracing(struct trace_array *tr);
1246 extern void disable_branch_tracing(void);
1247 static inline int trace_branch_enable(struct trace_array *tr)
1249 if (tr->trace_flags & TRACE_ITER_BRANCH)
1250 return enable_branch_tracing(tr);
1253 static inline void trace_branch_disable(void)
1255 /* due to races, always disable */
1256 disable_branch_tracing();
1259 static inline int trace_branch_enable(struct trace_array *tr)
1263 static inline void trace_branch_disable(void)
1266 #endif /* CONFIG_BRANCH_TRACER */
1268 /* set ring buffers to default size if not already done so */
1269 int tracing_update_buffers(void);
1271 struct ftrace_event_field {
1272 struct list_head link;
1283 struct event_filter {
1284 struct prog_entry __rcu *prog;
1285 char *filter_string;
1288 struct event_subsystem {
1289 struct list_head list;
1291 struct event_filter *filter;
1295 struct trace_subsystem_dir {
1296 struct list_head list;
1297 struct event_subsystem *subsystem;
1298 struct trace_array *tr;
1299 struct dentry *entry;
1304 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1305 struct ring_buffer *buffer,
1306 struct ring_buffer_event *event);
1308 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1309 struct ring_buffer *buffer,
1310 struct ring_buffer_event *event,
1311 unsigned long flags, int pc,
1312 struct pt_regs *regs);
1314 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1315 struct ring_buffer *buffer,
1316 struct ring_buffer_event *event,
1317 unsigned long flags, int pc)
1319 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1322 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1323 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1324 void trace_buffered_event_disable(void);
1325 void trace_buffered_event_enable(void);
1328 __trace_event_discard_commit(struct ring_buffer *buffer,
1329 struct ring_buffer_event *event)
1331 if (this_cpu_read(trace_buffered_event) == event) {
1332 /* Simply release the temp buffer */
1333 this_cpu_dec(trace_buffered_event_cnt);
1336 ring_buffer_discard_commit(buffer, event);
1340 * Helper function for event_trigger_unlock_commit{_regs}().
1341 * If there are event triggers attached to this event that requires
1342 * filtering against its fields, then they wil be called as the
1343 * entry already holds the field information of the current event.
1345 * It also checks if the event should be discarded or not.
1346 * It is to be discarded if the event is soft disabled and the
1347 * event was only recorded to process triggers, or if the event
1348 * filter is active and this event did not match the filters.
1350 * Returns true if the event is discarded, false otherwise.
1353 __event_trigger_test_discard(struct trace_event_file *file,
1354 struct ring_buffer *buffer,
1355 struct ring_buffer_event *event,
1357 enum event_trigger_type *tt)
1359 unsigned long eflags = file->flags;
1361 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1362 *tt = event_triggers_call(file, entry, event);
1364 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1365 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1366 !filter_match_preds(file->filter, entry))) {
1367 __trace_event_discard_commit(buffer, event);
1375 * event_trigger_unlock_commit - handle triggers and finish event commit
1376 * @file: The file pointer assoctiated to the event
1377 * @buffer: The ring buffer that the event is being written to
1378 * @event: The event meta data in the ring buffer
1379 * @entry: The event itself
1380 * @irq_flags: The state of the interrupts at the start of the event
1381 * @pc: The state of the preempt count at the start of the event.
1383 * This is a helper function to handle triggers that require data
1384 * from the event itself. It also tests the event against filters and
1385 * if the event is soft disabled and should be discarded.
1388 event_trigger_unlock_commit(struct trace_event_file *file,
1389 struct ring_buffer *buffer,
1390 struct ring_buffer_event *event,
1391 void *entry, unsigned long irq_flags, int pc)
1393 enum event_trigger_type tt = ETT_NONE;
1395 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1396 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1399 event_triggers_post_call(file, tt);
1403 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1404 * @file: The file pointer assoctiated to the event
1405 * @buffer: The ring buffer that the event is being written to
1406 * @event: The event meta data in the ring buffer
1407 * @entry: The event itself
1408 * @irq_flags: The state of the interrupts at the start of the event
1409 * @pc: The state of the preempt count at the start of the event.
1411 * This is a helper function to handle triggers that require data
1412 * from the event itself. It also tests the event against filters and
1413 * if the event is soft disabled and should be discarded.
1415 * Same as event_trigger_unlock_commit() but calls
1416 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1419 event_trigger_unlock_commit_regs(struct trace_event_file *file,
1420 struct ring_buffer *buffer,
1421 struct ring_buffer_event *event,
1422 void *entry, unsigned long irq_flags, int pc,
1423 struct pt_regs *regs)
1425 enum event_trigger_type tt = ETT_NONE;
1427 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1428 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1429 irq_flags, pc, regs);
1432 event_triggers_post_call(file, tt);
1435 #define FILTER_PRED_INVALID ((unsigned short)-1)
1436 #define FILTER_PRED_IS_RIGHT (1 << 15)
1437 #define FILTER_PRED_FOLD (1 << 15)
1440 * The max preds is the size of unsigned short with
1441 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1442 * and FOLD flags. The other is reserved.
1444 * 2^14 preds is way more than enough.
1446 #define MAX_FILTER_PRED 16384
1451 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1453 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1464 char pattern[MAX_FILTER_STR_VAL];
1467 regex_match_func match;
1470 struct filter_pred {
1471 filter_pred_fn_t fn;
1474 unsigned short *ops;
1475 struct ftrace_event_field *field;
1481 static inline bool is_string_field(struct ftrace_event_field *field)
1483 return field->filter_type == FILTER_DYN_STRING ||
1484 field->filter_type == FILTER_STATIC_STRING ||
1485 field->filter_type == FILTER_PTR_STRING ||
1486 field->filter_type == FILTER_COMM;
1489 static inline bool is_function_field(struct ftrace_event_field *field)
1491 return field->filter_type == FILTER_TRACE_FN;
1494 extern enum regex_type
1495 filter_parse_regex(char *buff, int len, char **search, int *not);
1496 extern void print_event_filter(struct trace_event_file *file,
1497 struct trace_seq *s);
1498 extern int apply_event_filter(struct trace_event_file *file,
1499 char *filter_string);
1500 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1501 char *filter_string);
1502 extern void print_subsystem_event_filter(struct event_subsystem *system,
1503 struct trace_seq *s);
1504 extern int filter_assign_type(const char *type);
1505 extern int create_event_filter(struct trace_event_call *call,
1506 char *filter_str, bool set_str,
1507 struct event_filter **filterp);
1508 extern void free_event_filter(struct event_filter *filter);
1510 struct ftrace_event_field *
1511 trace_find_event_field(struct trace_event_call *call, char *name);
1513 extern void trace_event_enable_cmd_record(bool enable);
1514 extern void trace_event_enable_tgid_record(bool enable);
1516 extern int event_trace_init(void);
1517 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1518 extern int event_trace_del_tracer(struct trace_array *tr);
1520 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1523 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1527 static inline void *event_file_data(struct file *filp)
1529 return READ_ONCE(file_inode(filp)->i_private);
1532 extern struct mutex event_mutex;
1533 extern struct list_head ftrace_events;
1535 extern const struct file_operations event_trigger_fops;
1536 extern const struct file_operations event_hist_fops;
1538 #ifdef CONFIG_HIST_TRIGGERS
1539 extern int register_trigger_hist_cmd(void);
1540 extern int register_trigger_hist_enable_disable_cmds(void);
1542 static inline int register_trigger_hist_cmd(void) { return 0; }
1543 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1546 extern int register_trigger_cmds(void);
1547 extern void clear_event_triggers(struct trace_array *tr);
1549 struct event_trigger_data {
1550 unsigned long count;
1552 struct event_trigger_ops *ops;
1553 struct event_command *cmd_ops;
1554 struct event_filter __rcu *filter;
1559 struct list_head list;
1561 struct list_head named_list;
1562 struct event_trigger_data *named_data;
1566 #define ENABLE_EVENT_STR "enable_event"
1567 #define DISABLE_EVENT_STR "disable_event"
1568 #define ENABLE_HIST_STR "enable_hist"
1569 #define DISABLE_HIST_STR "disable_hist"
1571 struct enable_trigger_data {
1572 struct trace_event_file *file;
1577 extern int event_enable_trigger_print(struct seq_file *m,
1578 struct event_trigger_ops *ops,
1579 struct event_trigger_data *data);
1580 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1581 struct event_trigger_data *data);
1582 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1583 struct trace_event_file *file,
1584 char *glob, char *cmd, char *param);
1585 extern int event_enable_register_trigger(char *glob,
1586 struct event_trigger_ops *ops,
1587 struct event_trigger_data *data,
1588 struct trace_event_file *file);
1589 extern void event_enable_unregister_trigger(char *glob,
1590 struct event_trigger_ops *ops,
1591 struct event_trigger_data *test,
1592 struct trace_event_file *file);
1593 extern void trigger_data_free(struct event_trigger_data *data);
1594 extern int event_trigger_init(struct event_trigger_ops *ops,
1595 struct event_trigger_data *data);
1596 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1597 int trigger_enable);
1598 extern void update_cond_flag(struct trace_event_file *file);
1599 extern int set_trigger_filter(char *filter_str,
1600 struct event_trigger_data *trigger_data,
1601 struct trace_event_file *file);
1602 extern struct event_trigger_data *find_named_trigger(const char *name);
1603 extern bool is_named_trigger(struct event_trigger_data *test);
1604 extern int save_named_trigger(const char *name,
1605 struct event_trigger_data *data);
1606 extern void del_named_trigger(struct event_trigger_data *data);
1607 extern void pause_named_trigger(struct event_trigger_data *data);
1608 extern void unpause_named_trigger(struct event_trigger_data *data);
1609 extern void set_named_trigger_data(struct event_trigger_data *data,
1610 struct event_trigger_data *named_data);
1611 extern struct event_trigger_data *
1612 get_named_trigger_data(struct event_trigger_data *data);
1613 extern int register_event_command(struct event_command *cmd);
1614 extern int unregister_event_command(struct event_command *cmd);
1615 extern int register_trigger_hist_enable_disable_cmds(void);
1618 * struct event_trigger_ops - callbacks for trace event triggers
1620 * The methods in this structure provide per-event trigger hooks for
1621 * various trigger operations.
1623 * All the methods below, except for @init() and @free(), must be
1626 * @func: The trigger 'probe' function called when the triggering
1627 * event occurs. The data passed into this callback is the data
1628 * that was supplied to the event_command @reg() function that
1629 * registered the trigger (see struct event_command) along with
1630 * the trace record, rec.
1632 * @init: An optional initialization function called for the trigger
1633 * when the trigger is registered (via the event_command reg()
1634 * function). This can be used to perform per-trigger
1635 * initialization such as incrementing a per-trigger reference
1636 * count, for instance. This is usually implemented by the
1637 * generic utility function @event_trigger_init() (see
1638 * trace_event_triggers.c).
1640 * @free: An optional de-initialization function called for the
1641 * trigger when the trigger is unregistered (via the
1642 * event_command @reg() function). This can be used to perform
1643 * per-trigger de-initialization such as decrementing a
1644 * per-trigger reference count and freeing corresponding trigger
1645 * data, for instance. This is usually implemented by the
1646 * generic utility function @event_trigger_free() (see
1647 * trace_event_triggers.c).
1649 * @print: The callback function invoked to have the trigger print
1650 * itself. This is usually implemented by a wrapper function
1651 * that calls the generic utility function @event_trigger_print()
1652 * (see trace_event_triggers.c).
1654 struct event_trigger_ops {
1655 void (*func)(struct event_trigger_data *data,
1657 struct ring_buffer_event *rbe);
1658 int (*init)(struct event_trigger_ops *ops,
1659 struct event_trigger_data *data);
1660 void (*free)(struct event_trigger_ops *ops,
1661 struct event_trigger_data *data);
1662 int (*print)(struct seq_file *m,
1663 struct event_trigger_ops *ops,
1664 struct event_trigger_data *data);
1668 * struct event_command - callbacks and data members for event commands
1670 * Event commands are invoked by users by writing the command name
1671 * into the 'trigger' file associated with a trace event. The
1672 * parameters associated with a specific invocation of an event
1673 * command are used to create an event trigger instance, which is
1674 * added to the list of trigger instances associated with that trace
1675 * event. When the event is hit, the set of triggers associated with
1676 * that event is invoked.
1678 * The data members in this structure provide per-event command data
1679 * for various event commands.
1681 * All the data members below, except for @post_trigger, must be set
1682 * for each event command.
1684 * @name: The unique name that identifies the event command. This is
1685 * the name used when setting triggers via trigger files.
1687 * @trigger_type: A unique id that identifies the event command
1688 * 'type'. This value has two purposes, the first to ensure that
1689 * only one trigger of the same type can be set at a given time
1690 * for a particular event e.g. it doesn't make sense to have both
1691 * a traceon and traceoff trigger attached to a single event at
1692 * the same time, so traceon and traceoff have the same type
1693 * though they have different names. The @trigger_type value is
1694 * also used as a bit value for deferring the actual trigger
1695 * action until after the current event is finished. Some
1696 * commands need to do this if they themselves log to the trace
1697 * buffer (see the @post_trigger() member below). @trigger_type
1698 * values are defined by adding new values to the trigger_type
1699 * enum in include/linux/trace_events.h.
1701 * @flags: See the enum event_command_flags below.
1703 * All the methods below, except for @set_filter() and @unreg_all(),
1704 * must be implemented.
1706 * @func: The callback function responsible for parsing and
1707 * registering the trigger written to the 'trigger' file by the
1708 * user. It allocates the trigger instance and registers it with
1709 * the appropriate trace event. It makes use of the other
1710 * event_command callback functions to orchestrate this, and is
1711 * usually implemented by the generic utility function
1712 * @event_trigger_callback() (see trace_event_triggers.c).
1714 * @reg: Adds the trigger to the list of triggers associated with the
1715 * event, and enables the event trigger itself, after
1716 * initializing it (via the event_trigger_ops @init() function).
1717 * This is also where commands can use the @trigger_type value to
1718 * make the decision as to whether or not multiple instances of
1719 * the trigger should be allowed. This is usually implemented by
1720 * the generic utility function @register_trigger() (see
1721 * trace_event_triggers.c).
1723 * @unreg: Removes the trigger from the list of triggers associated
1724 * with the event, and disables the event trigger itself, after
1725 * initializing it (via the event_trigger_ops @free() function).
1726 * This is usually implemented by the generic utility function
1727 * @unregister_trigger() (see trace_event_triggers.c).
1729 * @unreg_all: An optional function called to remove all the triggers
1730 * from the list of triggers associated with the event. Called
1731 * when a trigger file is opened in truncate mode.
1733 * @set_filter: An optional function called to parse and set a filter
1734 * for the trigger. If no @set_filter() method is set for the
1735 * event command, filters set by the user for the command will be
1736 * ignored. This is usually implemented by the generic utility
1737 * function @set_trigger_filter() (see trace_event_triggers.c).
1739 * @get_trigger_ops: The callback function invoked to retrieve the
1740 * event_trigger_ops implementation associated with the command.
1742 struct event_command {
1743 struct list_head list;
1745 enum event_trigger_type trigger_type;
1747 int (*func)(struct event_command *cmd_ops,
1748 struct trace_event_file *file,
1749 char *glob, char *cmd, char *params);
1750 int (*reg)(char *glob,
1751 struct event_trigger_ops *ops,
1752 struct event_trigger_data *data,
1753 struct trace_event_file *file);
1754 void (*unreg)(char *glob,
1755 struct event_trigger_ops *ops,
1756 struct event_trigger_data *data,
1757 struct trace_event_file *file);
1758 void (*unreg_all)(struct trace_event_file *file);
1759 int (*set_filter)(char *filter_str,
1760 struct event_trigger_data *data,
1761 struct trace_event_file *file);
1762 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1766 * enum event_command_flags - flags for struct event_command
1768 * @POST_TRIGGER: A flag that says whether or not this command needs
1769 * to have its action delayed until after the current event has
1770 * been closed. Some triggers need to avoid being invoked while
1771 * an event is currently in the process of being logged, since
1772 * the trigger may itself log data into the trace buffer. Thus
1773 * we make sure the current event is committed before invoking
1774 * those triggers. To do that, the trigger invocation is split
1775 * in two - the first part checks the filter using the current
1776 * trace record; if a command has the @post_trigger flag set, it
1777 * sets a bit for itself in the return value, otherwise it
1778 * directly invokes the trigger. Once all commands have been
1779 * either invoked or set their return flag, the current record is
1780 * either committed or discarded. At that point, if any commands
1781 * have deferred their triggers, those commands are finally
1782 * invoked following the close of the current event. In other
1783 * words, if the event_trigger_ops @func() probe implementation
1784 * itself logs to the trace buffer, this flag should be set,
1785 * otherwise it can be left unspecified.
1787 * @NEEDS_REC: A flag that says whether or not this command needs
1788 * access to the trace record in order to perform its function,
1789 * regardless of whether or not it has a filter associated with
1790 * it (filters make a trigger require access to the trace record
1791 * but are not always present).
1793 enum event_command_flags {
1794 EVENT_CMD_FL_POST_TRIGGER = 1,
1795 EVENT_CMD_FL_NEEDS_REC = 2,
1798 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1800 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1803 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1805 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1808 extern int trace_event_enable_disable(struct trace_event_file *file,
1809 int enable, int soft_disable);
1810 extern int tracing_alloc_snapshot(void);
1812 extern const char *__start___trace_bprintk_fmt[];
1813 extern const char *__stop___trace_bprintk_fmt[];
1815 extern const char *__start___tracepoint_str[];
1816 extern const char *__stop___tracepoint_str[];
1818 void trace_printk_control(bool enabled);
1819 void trace_printk_init_buffers(void);
1820 void trace_printk_start_comm(void);
1821 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1822 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1824 #define MAX_EVENT_NAME_LEN 64
1826 extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1827 extern ssize_t trace_parse_run_command(struct file *file,
1828 const char __user *buffer, size_t count, loff_t *ppos,
1829 int (*createfn)(int, char**));
1832 * Normal trace_printk() and friends allocates special buffers
1833 * to do the manipulation, as well as saves the print formats
1834 * into sections to display. But the trace infrastructure wants
1835 * to use these without the added overhead at the price of being
1836 * a bit slower (used mainly for warnings, where we don't care
1837 * about performance). The internal_trace_puts() is for such
1840 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1843 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1844 extern struct trace_event_call \
1845 __aligned(4) event_##call;
1846 #undef FTRACE_ENTRY_DUP
1847 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1848 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1850 #undef FTRACE_ENTRY_PACKED
1851 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1852 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1855 #include "trace_entries.h"
1857 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1858 int perf_ftrace_event_register(struct trace_event_call *call,
1859 enum trace_reg type, void *data);
1861 #define perf_ftrace_event_register NULL
1864 #ifdef CONFIG_FTRACE_SYSCALLS
1865 void init_ftrace_syscalls(void);
1866 const char *get_syscall_name(int syscall);
1868 static inline void init_ftrace_syscalls(void) { }
1869 static inline const char *get_syscall_name(int syscall)
1875 #ifdef CONFIG_EVENT_TRACING
1876 void trace_event_init(void);
1877 void trace_event_eval_update(struct trace_eval_map **map, int len);
1879 static inline void __init trace_event_init(void) { }
1880 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1883 #ifdef CONFIG_TRACER_SNAPSHOT
1884 void tracing_snapshot_instance(struct trace_array *tr);
1885 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1887 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1888 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1894 #ifdef CONFIG_PREEMPT_TRACER
1895 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1896 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1898 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1899 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1901 #ifdef CONFIG_IRQSOFF_TRACER
1902 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1903 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1905 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1906 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1909 extern struct trace_iterator *tracepoint_print_iter;
1911 #endif /* _LINUX_KERNEL_TRACE_H */