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];
250 struct tracer *current_trace;
251 unsigned int trace_flags;
252 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
254 raw_spinlock_t start_lock;
256 struct dentry *options;
257 struct dentry *percpu_dir;
258 struct dentry *event_dir;
259 struct trace_options *topts;
260 struct list_head systems;
261 struct list_head events;
262 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
264 #ifdef CONFIG_FUNCTION_TRACER
265 struct ftrace_ops *ops;
266 struct trace_pid_list __rcu *function_pids;
267 #ifdef CONFIG_DYNAMIC_FTRACE
268 /* All of these are protected by the ftrace_lock */
269 struct list_head func_probes;
270 struct list_head mod_trace;
271 struct list_head mod_notrace;
273 /* function tracing enabled */
274 int function_enabled;
279 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
282 extern struct list_head ftrace_trace_arrays;
284 extern struct mutex trace_types_lock;
286 extern int trace_array_get(struct trace_array *tr);
287 extern void trace_array_put(struct trace_array *tr);
290 * The global tracer (top) should be the first trace array added,
291 * but we check the flag anyway.
293 static inline struct trace_array *top_trace_array(void)
295 struct trace_array *tr;
297 if (list_empty(&ftrace_trace_arrays))
300 tr = list_entry(ftrace_trace_arrays.prev,
302 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
306 #define FTRACE_CMP_TYPE(var, type) \
307 __builtin_types_compatible_p(typeof(var), type *)
310 #define IF_ASSIGN(var, entry, etype, id) \
311 if (FTRACE_CMP_TYPE(var, etype)) { \
312 var = (typeof(var))(entry); \
313 WARN_ON(id && (entry)->type != id); \
317 /* Will cause compile errors if type is not found. */
318 extern void __ftrace_bad_type(void);
321 * The trace_assign_type is a verifier that the entry type is
322 * the same as the type being assigned. To add new types simply
323 * add a line with the following format:
325 * IF_ASSIGN(var, ent, type, id);
327 * Where "type" is the trace type that includes the trace_entry
328 * as the "ent" item. And "id" is the trace identifier that is
329 * used in the trace_type enum.
331 * If the type can have more than one id, then use zero.
333 #define trace_assign_type(var, ent) \
335 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
336 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
337 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
338 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
339 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
340 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
341 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
342 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
343 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
344 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
346 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
348 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
349 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
351 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
353 __ftrace_bad_type(); \
357 * An option specific to a tracer. This is a boolean value.
358 * The bit is the bit index that sets its value on the
359 * flags value in struct tracer_flags.
362 const char *name; /* Will appear on the trace_options file */
363 u32 bit; /* Mask assigned in val field in tracer_flags */
367 * The set of specific options for a tracer. Your tracer
368 * have to set the initial value of the flags val.
370 struct tracer_flags {
372 struct tracer_opt *opts;
373 struct tracer *trace;
376 /* Makes more easy to define a tracer opt */
377 #define TRACER_OPT(s, b) .name = #s, .bit = b
380 struct trace_option_dentry {
381 struct tracer_opt *opt;
382 struct tracer_flags *flags;
383 struct trace_array *tr;
384 struct dentry *entry;
388 * struct tracer - a specific tracer and its callbacks to interact with tracefs
389 * @name: the name chosen to select it on the available_tracers file
390 * @init: called when one switches to this tracer (echo name > current_tracer)
391 * @reset: called when one switches to another tracer
392 * @start: called when tracing is unpaused (echo 1 > tracing_on)
393 * @stop: called when tracing is paused (echo 0 > tracing_on)
394 * @update_thresh: called when tracing_thresh is updated
395 * @open: called when the trace file is opened
396 * @pipe_open: called when the trace_pipe file is opened
397 * @close: called when the trace file is released
398 * @pipe_close: called when the trace_pipe file is released
399 * @read: override the default read callback on trace_pipe
400 * @splice_read: override the default splice_read callback on trace_pipe
401 * @selftest: selftest to run on boot (see trace_selftest.c)
402 * @print_headers: override the first lines that describe your columns
403 * @print_line: callback that prints a trace
404 * @set_flag: signals one of your private flags changed (trace_options file)
405 * @flags: your private flags
409 int (*init)(struct trace_array *tr);
410 void (*reset)(struct trace_array *tr);
411 void (*start)(struct trace_array *tr);
412 void (*stop)(struct trace_array *tr);
413 int (*update_thresh)(struct trace_array *tr);
414 void (*open)(struct trace_iterator *iter);
415 void (*pipe_open)(struct trace_iterator *iter);
416 void (*close)(struct trace_iterator *iter);
417 void (*pipe_close)(struct trace_iterator *iter);
418 ssize_t (*read)(struct trace_iterator *iter,
419 struct file *filp, char __user *ubuf,
420 size_t cnt, loff_t *ppos);
421 ssize_t (*splice_read)(struct trace_iterator *iter,
424 struct pipe_inode_info *pipe,
427 #ifdef CONFIG_FTRACE_STARTUP_TEST
428 int (*selftest)(struct tracer *trace,
429 struct trace_array *tr);
431 void (*print_header)(struct seq_file *m);
432 enum print_line_t (*print_line)(struct trace_iterator *iter);
433 /* If you handled the flag setting, return 0 */
434 int (*set_flag)(struct trace_array *tr,
435 u32 old_flags, u32 bit, int set);
436 /* Return 0 if OK with change, else return non-zero */
437 int (*flag_changed)(struct trace_array *tr,
440 struct tracer_flags *flags;
444 bool allow_instances;
445 #ifdef CONFIG_TRACER_MAX_TRACE
448 /* True if tracer cannot be enabled in kernel param */
453 /* Only current can touch trace_recursion */
456 * For function tracing recursion:
457 * The order of these bits are important.
459 * When function tracing occurs, the following steps are made:
460 * If arch does not support a ftrace feature:
461 * call internal function (uses INTERNAL bits) which calls...
462 * If callback is registered to the "global" list, the list
463 * function is called and recursion checks the GLOBAL bits.
464 * then this function calls...
465 * The function callback, which can use the FTRACE bits to
466 * check for recursion.
468 * Now if the arch does not suppport a feature, and it calls
469 * the global list function which calls the ftrace callback
470 * all three of these steps will do a recursion protection.
471 * There's no reason to do one if the previous caller already
472 * did. The recursion that we are protecting against will
473 * go through the same steps again.
475 * To prevent the multiple recursion checks, if a recursion
476 * bit is set that is higher than the MAX bit of the current
477 * check, then we know that the check was made by the previous
478 * caller, and we can skip the current check.
482 TRACE_BUFFER_NMI_BIT,
483 TRACE_BUFFER_IRQ_BIT,
484 TRACE_BUFFER_SIRQ_BIT,
486 /* Start of function recursion bits */
488 TRACE_FTRACE_NMI_BIT,
489 TRACE_FTRACE_IRQ_BIT,
490 TRACE_FTRACE_SIRQ_BIT,
492 /* INTERNAL_BITs must be greater than FTRACE_BITs */
494 TRACE_INTERNAL_NMI_BIT,
495 TRACE_INTERNAL_IRQ_BIT,
496 TRACE_INTERNAL_SIRQ_BIT,
500 * Abuse of the trace_recursion.
501 * As we need a way to maintain state if we are tracing the function
502 * graph in irq because we want to trace a particular function that
503 * was called in irq context but we have irq tracing off. Since this
504 * can only be modified by current, we can reuse trace_recursion.
508 /* Set if the function is in the set_graph_function file */
512 * In the very unlikely case that an interrupt came in
513 * at a start of graph tracing, and we want to trace
514 * the function in that interrupt, the depth can be greater
515 * than zero, because of the preempted start of a previous
516 * trace. In an even more unlikely case, depth could be 2
517 * if a softirq interrupted the start of graph tracing,
518 * followed by an interrupt preempting a start of graph
519 * tracing in the softirq, and depth can even be 3
520 * if an NMI came in at the start of an interrupt function
521 * that preempted a softirq start of a function that
522 * preempted normal context!!!! Luckily, it can't be
523 * greater than 3, so the next two bits are a mask
524 * of what the depth is when we set TRACE_GRAPH_BIT
527 TRACE_GRAPH_DEPTH_START_BIT,
528 TRACE_GRAPH_DEPTH_END_BIT,
531 * When transitioning between context, the preempt_count() may
532 * not be correct. Allow for a single recursion to cover this case.
534 TRACE_TRANSITION_BIT,
537 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
538 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
539 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
541 #define trace_recursion_depth() \
542 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
543 #define trace_recursion_set_depth(depth) \
545 current->trace_recursion &= \
546 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
547 current->trace_recursion |= \
548 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
551 #define TRACE_CONTEXT_BITS 4
553 #define TRACE_FTRACE_START TRACE_FTRACE_BIT
554 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
556 #define TRACE_LIST_START TRACE_INTERNAL_BIT
557 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
559 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX
561 static __always_inline int trace_get_context_bit(void)
565 if (in_interrupt()) {
579 static __always_inline int trace_test_and_set_recursion(int start, int max)
581 unsigned int val = current->trace_recursion;
584 /* A previous recursion check was made */
585 if ((val & TRACE_CONTEXT_MASK) > max)
588 bit = trace_get_context_bit() + start;
589 if (unlikely(val & (1 << bit))) {
591 * It could be that preempt_count has not been updated during
592 * a switch between contexts. Allow for a single recursion.
594 bit = TRACE_TRANSITION_BIT;
595 if (trace_recursion_test(bit))
597 trace_recursion_set(bit);
602 /* Normal check passed, clear the transition to allow it again */
603 trace_recursion_clear(TRACE_TRANSITION_BIT);
606 current->trace_recursion = val;
612 static __always_inline void trace_clear_recursion(int bit)
614 unsigned int val = current->trace_recursion;
624 current->trace_recursion = val;
627 static inline struct ring_buffer_iter *
628 trace_buffer_iter(struct trace_iterator *iter, int cpu)
630 if (iter->buffer_iter && iter->buffer_iter[cpu])
631 return iter->buffer_iter[cpu];
635 int tracer_init(struct tracer *t, struct trace_array *tr);
636 int tracing_is_enabled(void);
637 void tracing_reset(struct trace_buffer *buf, int cpu);
638 void tracing_reset_online_cpus(struct trace_buffer *buf);
639 void tracing_reset_current(int cpu);
640 void tracing_reset_all_online_cpus(void);
641 int tracing_open_generic(struct inode *inode, struct file *filp);
642 bool tracing_is_disabled(void);
643 int tracer_tracing_is_on(struct trace_array *tr);
644 void tracer_tracing_on(struct trace_array *tr);
645 void tracer_tracing_off(struct trace_array *tr);
646 struct dentry *trace_create_file(const char *name,
648 struct dentry *parent,
650 const struct file_operations *fops);
652 struct dentry *tracing_init_dentry(void);
654 struct ring_buffer_event;
656 struct ring_buffer_event *
657 trace_buffer_lock_reserve(struct ring_buffer *buffer,
663 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
664 struct trace_array_cpu *data);
666 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
667 int *ent_cpu, u64 *ent_ts);
669 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
670 struct ring_buffer_event *event);
672 int trace_empty(struct trace_iterator *iter);
674 void *trace_find_next_entry_inc(struct trace_iterator *iter);
676 void trace_init_global_iter(struct trace_iterator *iter);
678 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
680 void trace_function(struct trace_array *tr,
682 unsigned long parent_ip,
683 unsigned long flags, int pc);
684 void trace_graph_function(struct trace_array *tr,
686 unsigned long parent_ip,
687 unsigned long flags, int pc);
688 void trace_latency_header(struct seq_file *m);
689 void trace_default_header(struct seq_file *m);
690 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
691 int trace_empty(struct trace_iterator *iter);
693 void trace_graph_return(struct ftrace_graph_ret *trace);
694 int trace_graph_entry(struct ftrace_graph_ent *trace);
695 void set_graph_array(struct trace_array *tr);
697 void tracing_start_cmdline_record(void);
698 void tracing_stop_cmdline_record(void);
699 void tracing_start_tgid_record(void);
700 void tracing_stop_tgid_record(void);
702 int register_tracer(struct tracer *type);
703 int is_tracing_stopped(void);
705 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
707 extern cpumask_var_t __read_mostly tracing_buffer_mask;
709 #define for_each_tracing_cpu(cpu) \
710 for_each_cpu(cpu, tracing_buffer_mask)
712 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
714 extern unsigned long tracing_thresh;
720 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
722 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
723 struct task_struct *task);
724 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
725 struct task_struct *self,
726 struct task_struct *task);
727 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
728 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
729 int trace_pid_show(struct seq_file *m, void *v);
730 void trace_free_pid_list(struct trace_pid_list *pid_list);
731 int trace_pid_write(struct trace_pid_list *filtered_pids,
732 struct trace_pid_list **new_pid_list,
733 const char __user *ubuf, size_t cnt);
735 #ifdef CONFIG_TRACER_MAX_TRACE
736 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
737 void update_max_tr_single(struct trace_array *tr,
738 struct task_struct *tsk, int cpu);
739 #endif /* CONFIG_TRACER_MAX_TRACE */
741 #ifdef CONFIG_STACKTRACE
742 void ftrace_trace_userstack(struct trace_array *tr,
743 struct ring_buffer *buffer, unsigned long flags,
746 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
749 static inline void ftrace_trace_userstack(struct trace_array *tr,
750 struct ring_buffer *buffer,
751 unsigned long flags, int pc)
755 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
759 #endif /* CONFIG_STACKTRACE */
761 extern u64 ftrace_now(int cpu);
763 extern void trace_find_cmdline(int pid, char comm[]);
764 extern int trace_find_tgid(int pid);
765 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
767 #ifdef CONFIG_DYNAMIC_FTRACE
768 extern unsigned long ftrace_update_tot_cnt;
769 void ftrace_init_trace_array(struct trace_array *tr);
771 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
773 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
774 extern int DYN_FTRACE_TEST_NAME(void);
775 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
776 extern int DYN_FTRACE_TEST_NAME2(void);
778 extern bool ring_buffer_expanded;
779 extern bool tracing_selftest_disabled;
781 #ifdef CONFIG_FTRACE_STARTUP_TEST
782 extern int trace_selftest_startup_function(struct tracer *trace,
783 struct trace_array *tr);
784 extern int trace_selftest_startup_function_graph(struct tracer *trace,
785 struct trace_array *tr);
786 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
787 struct trace_array *tr);
788 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
789 struct trace_array *tr);
790 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
791 struct trace_array *tr);
792 extern int trace_selftest_startup_wakeup(struct tracer *trace,
793 struct trace_array *tr);
794 extern int trace_selftest_startup_nop(struct tracer *trace,
795 struct trace_array *tr);
796 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
797 struct trace_array *tr);
798 extern int trace_selftest_startup_branch(struct tracer *trace,
799 struct trace_array *tr);
801 * Tracer data references selftest functions that only occur
802 * on boot up. These can be __init functions. Thus, when selftests
803 * are enabled, then the tracers need to reference __init functions.
805 #define __tracer_data __refdata
807 /* Tracers are seldom changed. Optimize when selftests are disabled. */
808 #define __tracer_data __read_mostly
809 #endif /* CONFIG_FTRACE_STARTUP_TEST */
811 extern void *head_page(struct trace_array_cpu *data);
812 extern unsigned long long ns2usecs(u64 nsec);
814 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
816 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
818 trace_array_vprintk(struct trace_array *tr,
819 unsigned long ip, const char *fmt, va_list args);
820 int trace_array_printk(struct trace_array *tr,
821 unsigned long ip, const char *fmt, ...);
822 int trace_array_printk_buf(struct ring_buffer *buffer,
823 unsigned long ip, const char *fmt, ...);
824 void trace_printk_seq(struct trace_seq *s);
825 enum print_line_t print_trace_line(struct trace_iterator *iter);
827 extern char trace_find_mark(unsigned long long duration);
831 struct ftrace_mod_load {
832 struct list_head list;
839 FTRACE_HASH_FL_MOD = (1 << 0),
843 unsigned long size_bits;
844 struct hlist_head *buckets;
850 struct ftrace_func_entry *
851 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
853 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
855 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
858 /* Standard output formatting function used for function return traces */
859 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
862 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
863 #define TRACE_GRAPH_PRINT_CPU 0x2
864 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
865 #define TRACE_GRAPH_PRINT_PROC 0x8
866 #define TRACE_GRAPH_PRINT_DURATION 0x10
867 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
868 #define TRACE_GRAPH_PRINT_IRQS 0x40
869 #define TRACE_GRAPH_PRINT_TAIL 0x80
870 #define TRACE_GRAPH_SLEEP_TIME 0x100
871 #define TRACE_GRAPH_GRAPH_TIME 0x200
872 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
873 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
875 extern void ftrace_graph_sleep_time_control(bool enable);
876 extern void ftrace_graph_graph_time_control(bool enable);
878 extern enum print_line_t
879 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
880 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
882 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
883 extern void graph_trace_open(struct trace_iterator *iter);
884 extern void graph_trace_close(struct trace_iterator *iter);
885 extern int __trace_graph_entry(struct trace_array *tr,
886 struct ftrace_graph_ent *trace,
887 unsigned long flags, int pc);
888 extern void __trace_graph_return(struct trace_array *tr,
889 struct ftrace_graph_ret *trace,
890 unsigned long flags, int pc);
892 #ifdef CONFIG_DYNAMIC_FTRACE
893 extern struct ftrace_hash __rcu *ftrace_graph_hash;
894 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
896 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
898 unsigned long addr = trace->func;
900 struct ftrace_hash *hash;
902 preempt_disable_notrace();
905 * Have to open code "rcu_dereference_sched()" because the
906 * function graph tracer can be called when RCU is not
908 * Protected with schedule_on_each_cpu(ftrace_sync)
910 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
912 if (ftrace_hash_empty(hash)) {
917 if (ftrace_lookup_ip(hash, addr)) {
920 * This needs to be cleared on the return functions
921 * when the depth is zero.
923 trace_recursion_set(TRACE_GRAPH_BIT);
924 trace_recursion_set_depth(trace->depth);
927 * If no irqs are to be traced, but a set_graph_function
928 * is set, and called by an interrupt handler, we still
932 trace_recursion_set(TRACE_IRQ_BIT);
934 trace_recursion_clear(TRACE_IRQ_BIT);
939 preempt_enable_notrace();
943 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
945 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
946 trace->depth == trace_recursion_depth())
947 trace_recursion_clear(TRACE_GRAPH_BIT);
950 static inline int ftrace_graph_notrace_addr(unsigned long addr)
953 struct ftrace_hash *notrace_hash;
955 preempt_disable_notrace();
958 * Have to open code "rcu_dereference_sched()" because the
959 * function graph tracer can be called when RCU is not
961 * Protected with schedule_on_each_cpu(ftrace_sync)
963 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
966 if (ftrace_lookup_ip(notrace_hash, addr))
969 preempt_enable_notrace();
973 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
978 static inline int ftrace_graph_notrace_addr(unsigned long addr)
982 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
984 #endif /* CONFIG_DYNAMIC_FTRACE */
986 extern unsigned int fgraph_max_depth;
988 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
990 /* trace it when it is-nested-in or is a function enabled. */
991 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
992 ftrace_graph_addr(trace)) ||
993 (trace->depth < 0) ||
994 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
997 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
998 static inline enum print_line_t
999 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1001 return TRACE_TYPE_UNHANDLED;
1003 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1005 extern struct list_head ftrace_pids;
1007 #ifdef CONFIG_FUNCTION_TRACER
1008 struct ftrace_func_command {
1009 struct list_head list;
1011 int (*func)(struct trace_array *tr,
1012 struct ftrace_hash *hash,
1013 char *func, char *cmd,
1014 char *params, int enable);
1016 extern bool ftrace_filter_param __initdata;
1017 static inline int ftrace_trace_task(struct trace_array *tr)
1019 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
1021 extern int ftrace_is_dead(void);
1022 int ftrace_create_function_files(struct trace_array *tr,
1023 struct dentry *parent);
1024 void ftrace_destroy_function_files(struct trace_array *tr);
1025 void ftrace_init_global_array_ops(struct trace_array *tr);
1026 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1027 void ftrace_reset_array_ops(struct trace_array *tr);
1028 int using_ftrace_ops_list_func(void);
1029 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1030 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1031 struct dentry *d_tracer);
1032 void ftrace_clear_pids(struct trace_array *tr);
1033 int init_function_trace(void);
1034 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1036 static inline int ftrace_trace_task(struct trace_array *tr)
1040 static inline int ftrace_is_dead(void) { return 0; }
1042 ftrace_create_function_files(struct trace_array *tr,
1043 struct dentry *parent)
1047 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1048 static inline __init void
1049 ftrace_init_global_array_ops(struct trace_array *tr) { }
1050 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1051 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1052 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1053 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1054 static inline int init_function_trace(void) { return 0; }
1055 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1056 /* ftace_func_t type is not defined, use macro instead of static inline */
1057 #define ftrace_init_array_ops(tr, func) do { } while (0)
1058 #endif /* CONFIG_FUNCTION_TRACER */
1060 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1062 struct ftrace_probe_ops {
1063 void (*func)(unsigned long ip,
1064 unsigned long parent_ip,
1065 struct trace_array *tr,
1066 struct ftrace_probe_ops *ops,
1068 int (*init)(struct ftrace_probe_ops *ops,
1069 struct trace_array *tr,
1070 unsigned long ip, void *init_data,
1072 void (*free)(struct ftrace_probe_ops *ops,
1073 struct trace_array *tr,
1074 unsigned long ip, void *data);
1075 int (*print)(struct seq_file *m,
1077 struct ftrace_probe_ops *ops,
1081 struct ftrace_func_mapper;
1082 typedef int (*ftrace_mapper_func)(void *data);
1084 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1085 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1087 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1088 unsigned long ip, void *data);
1089 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1091 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1092 ftrace_mapper_func free_func);
1095 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1096 struct ftrace_probe_ops *ops, void *data);
1098 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1099 struct ftrace_probe_ops *ops);
1100 extern void clear_ftrace_function_probes(struct trace_array *tr);
1102 int register_ftrace_command(struct ftrace_func_command *cmd);
1103 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1105 void ftrace_create_filter_files(struct ftrace_ops *ops,
1106 struct dentry *parent);
1107 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1109 struct ftrace_func_command;
1111 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1115 static inline __init int unregister_ftrace_command(char *cmd_name)
1119 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1124 * The ops parameter passed in is usually undefined.
1125 * This must be a macro.
1127 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1128 #define ftrace_destroy_filter_files(ops) do { } while (0)
1129 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1131 bool ftrace_event_is_function(struct trace_event_call *call);
1134 * struct trace_parser - servers for reading the user input separated by spaces
1135 * @cont: set if the input is not complete - no final space char was found
1136 * @buffer: holds the parsed user input
1137 * @idx: user input length
1138 * @size: buffer size
1140 struct trace_parser {
1147 static inline bool trace_parser_loaded(struct trace_parser *parser)
1149 return (parser->idx != 0);
1152 static inline bool trace_parser_cont(struct trace_parser *parser)
1154 return parser->cont;
1157 static inline void trace_parser_clear(struct trace_parser *parser)
1159 parser->cont = false;
1163 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1164 extern void trace_parser_put(struct trace_parser *parser);
1165 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1166 size_t cnt, loff_t *ppos);
1169 * Only create function graph options if function graph is configured.
1171 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1172 # define FGRAPH_FLAGS \
1173 C(DISPLAY_GRAPH, "display-graph"),
1175 # define FGRAPH_FLAGS
1178 #ifdef CONFIG_BRANCH_TRACER
1179 # define BRANCH_FLAGS \
1180 C(BRANCH, "branch"),
1182 # define BRANCH_FLAGS
1185 #ifdef CONFIG_FUNCTION_TRACER
1186 # define FUNCTION_FLAGS \
1187 C(FUNCTION, "function-trace"), \
1188 C(FUNC_FORK, "function-fork"),
1189 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1191 # define FUNCTION_FLAGS
1192 # define FUNCTION_DEFAULT_FLAGS 0UL
1193 # define TRACE_ITER_FUNC_FORK 0UL
1196 #ifdef CONFIG_STACKTRACE
1197 # define STACK_FLAGS \
1198 C(STACKTRACE, "stacktrace"),
1200 # define STACK_FLAGS
1204 * trace_iterator_flags is an enumeration that defines bit
1205 * positions into trace_flags that controls the output.
1207 * NOTE: These bits must match the trace_options array in
1208 * trace.c (this macro guarantees it).
1210 #define TRACE_FLAGS \
1211 C(PRINT_PARENT, "print-parent"), \
1212 C(SYM_OFFSET, "sym-offset"), \
1213 C(SYM_ADDR, "sym-addr"), \
1214 C(VERBOSE, "verbose"), \
1218 C(BLOCK, "block"), \
1219 C(PRINTK, "trace_printk"), \
1220 C(ANNOTATE, "annotate"), \
1221 C(USERSTACKTRACE, "userstacktrace"), \
1222 C(SYM_USEROBJ, "sym-userobj"), \
1223 C(PRINTK_MSGONLY, "printk-msg-only"), \
1224 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1225 C(LATENCY_FMT, "latency-format"), \
1226 C(RECORD_CMD, "record-cmd"), \
1227 C(RECORD_TGID, "record-tgid"), \
1228 C(OVERWRITE, "overwrite"), \
1229 C(STOP_ON_FREE, "disable_on_free"), \
1230 C(IRQ_INFO, "irq-info"), \
1231 C(MARKERS, "markers"), \
1232 C(EVENT_FORK, "event-fork"), \
1239 * By defining C, we can make TRACE_FLAGS a list of bit names
1240 * that will define the bits for the flag masks.
1243 #define C(a, b) TRACE_ITER_##a##_BIT
1245 enum trace_iterator_bits {
1247 /* Make sure we don't go more than we have bits for */
1252 * By redefining C, we can make TRACE_FLAGS a list of masks that
1253 * use the bits as defined above.
1256 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1258 enum trace_iterator_flags { TRACE_FLAGS };
1261 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1262 * control the output of kernel symbols.
1264 #define TRACE_ITER_SYM_MASK \
1265 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1267 extern struct tracer nop_trace;
1269 #ifdef CONFIG_BRANCH_TRACER
1270 extern int enable_branch_tracing(struct trace_array *tr);
1271 extern void disable_branch_tracing(void);
1272 static inline int trace_branch_enable(struct trace_array *tr)
1274 if (tr->trace_flags & TRACE_ITER_BRANCH)
1275 return enable_branch_tracing(tr);
1278 static inline void trace_branch_disable(void)
1280 /* due to races, always disable */
1281 disable_branch_tracing();
1284 static inline int trace_branch_enable(struct trace_array *tr)
1288 static inline void trace_branch_disable(void)
1291 #endif /* CONFIG_BRANCH_TRACER */
1293 /* set ring buffers to default size if not already done so */
1294 int tracing_update_buffers(void);
1296 struct ftrace_event_field {
1297 struct list_head link;
1306 struct event_filter {
1307 int n_preds; /* Number assigned */
1308 int a_preds; /* allocated */
1309 struct filter_pred __rcu *preds;
1310 struct filter_pred __rcu *root;
1311 char *filter_string;
1314 struct event_subsystem {
1315 struct list_head list;
1317 struct event_filter *filter;
1321 struct trace_subsystem_dir {
1322 struct list_head list;
1323 struct event_subsystem *subsystem;
1324 struct trace_array *tr;
1325 struct dentry *entry;
1330 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1331 struct ring_buffer *buffer,
1332 struct ring_buffer_event *event);
1334 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1335 struct ring_buffer *buffer,
1336 struct ring_buffer_event *event,
1337 unsigned long flags, int pc,
1338 struct pt_regs *regs);
1340 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1341 struct ring_buffer *buffer,
1342 struct ring_buffer_event *event,
1343 unsigned long flags, int pc)
1345 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1348 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1349 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1350 void trace_buffered_event_disable(void);
1351 void trace_buffered_event_enable(void);
1354 __trace_event_discard_commit(struct ring_buffer *buffer,
1355 struct ring_buffer_event *event)
1357 if (this_cpu_read(trace_buffered_event) == event) {
1358 /* Simply release the temp buffer */
1359 this_cpu_dec(trace_buffered_event_cnt);
1362 ring_buffer_discard_commit(buffer, event);
1366 * Helper function for event_trigger_unlock_commit{_regs}().
1367 * If there are event triggers attached to this event that requires
1368 * filtering against its fields, then they wil be called as the
1369 * entry already holds the field information of the current event.
1371 * It also checks if the event should be discarded or not.
1372 * It is to be discarded if the event is soft disabled and the
1373 * event was only recorded to process triggers, or if the event
1374 * filter is active and this event did not match the filters.
1376 * Returns true if the event is discarded, false otherwise.
1379 __event_trigger_test_discard(struct trace_event_file *file,
1380 struct ring_buffer *buffer,
1381 struct ring_buffer_event *event,
1383 enum event_trigger_type *tt)
1385 unsigned long eflags = file->flags;
1387 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1388 *tt = event_triggers_call(file, entry);
1390 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1391 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1392 !filter_match_preds(file->filter, entry))) {
1393 __trace_event_discard_commit(buffer, event);
1401 * event_trigger_unlock_commit - handle triggers and finish event commit
1402 * @file: The file pointer assoctiated to the event
1403 * @buffer: The ring buffer that the event is being written to
1404 * @event: The event meta data in the ring buffer
1405 * @entry: The event itself
1406 * @irq_flags: The state of the interrupts at the start of the event
1407 * @pc: The state of the preempt count at the start of the event.
1409 * This is a helper function to handle triggers that require data
1410 * from the event itself. It also tests the event against filters and
1411 * if the event is soft disabled and should be discarded.
1414 event_trigger_unlock_commit(struct trace_event_file *file,
1415 struct ring_buffer *buffer,
1416 struct ring_buffer_event *event,
1417 void *entry, unsigned long irq_flags, int pc)
1419 enum event_trigger_type tt = ETT_NONE;
1421 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1422 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1425 event_triggers_post_call(file, tt, entry);
1429 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1430 * @file: The file pointer assoctiated to the event
1431 * @buffer: The ring buffer that the event is being written to
1432 * @event: The event meta data in the ring buffer
1433 * @entry: The event itself
1434 * @irq_flags: The state of the interrupts at the start of the event
1435 * @pc: The state of the preempt count at the start of the event.
1437 * This is a helper function to handle triggers that require data
1438 * from the event itself. It also tests the event against filters and
1439 * if the event is soft disabled and should be discarded.
1441 * Same as event_trigger_unlock_commit() but calls
1442 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1445 event_trigger_unlock_commit_regs(struct trace_event_file *file,
1446 struct ring_buffer *buffer,
1447 struct ring_buffer_event *event,
1448 void *entry, unsigned long irq_flags, int pc,
1449 struct pt_regs *regs)
1451 enum event_trigger_type tt = ETT_NONE;
1453 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1454 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1455 irq_flags, pc, regs);
1458 event_triggers_post_call(file, tt, entry);
1461 #define FILTER_PRED_INVALID ((unsigned short)-1)
1462 #define FILTER_PRED_IS_RIGHT (1 << 15)
1463 #define FILTER_PRED_FOLD (1 << 15)
1466 * The max preds is the size of unsigned short with
1467 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1468 * and FOLD flags. The other is reserved.
1470 * 2^14 preds is way more than enough.
1472 #define MAX_FILTER_PRED 16384
1477 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1479 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1490 char pattern[MAX_FILTER_STR_VAL];
1493 regex_match_func match;
1496 struct filter_pred {
1497 filter_pred_fn_t fn;
1500 unsigned short *ops;
1501 struct ftrace_event_field *field;
1505 unsigned short index;
1506 unsigned short parent;
1507 unsigned short left;
1508 unsigned short right;
1511 static inline bool is_string_field(struct ftrace_event_field *field)
1513 return field->filter_type == FILTER_DYN_STRING ||
1514 field->filter_type == FILTER_STATIC_STRING ||
1515 field->filter_type == FILTER_PTR_STRING ||
1516 field->filter_type == FILTER_COMM;
1519 static inline bool is_function_field(struct ftrace_event_field *field)
1521 return field->filter_type == FILTER_TRACE_FN;
1524 extern enum regex_type
1525 filter_parse_regex(char *buff, int len, char **search, int *not);
1526 extern void print_event_filter(struct trace_event_file *file,
1527 struct trace_seq *s);
1528 extern int apply_event_filter(struct trace_event_file *file,
1529 char *filter_string);
1530 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1531 char *filter_string);
1532 extern void print_subsystem_event_filter(struct event_subsystem *system,
1533 struct trace_seq *s);
1534 extern int filter_assign_type(const char *type);
1535 extern int create_event_filter(struct trace_event_call *call,
1536 char *filter_str, bool set_str,
1537 struct event_filter **filterp);
1538 extern void free_event_filter(struct event_filter *filter);
1540 struct ftrace_event_field *
1541 trace_find_event_field(struct trace_event_call *call, char *name);
1543 extern void trace_event_enable_cmd_record(bool enable);
1544 extern void trace_event_enable_tgid_record(bool enable);
1546 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1547 extern int event_trace_del_tracer(struct trace_array *tr);
1549 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1553 static inline void *event_file_data(struct file *filp)
1555 return ACCESS_ONCE(file_inode(filp)->i_private);
1558 extern struct mutex event_mutex;
1559 extern struct list_head ftrace_events;
1561 extern const struct file_operations event_trigger_fops;
1562 extern const struct file_operations event_hist_fops;
1564 #ifdef CONFIG_HIST_TRIGGERS
1565 extern int register_trigger_hist_cmd(void);
1566 extern int register_trigger_hist_enable_disable_cmds(void);
1568 static inline int register_trigger_hist_cmd(void) { return 0; }
1569 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1572 extern int register_trigger_cmds(void);
1573 extern void clear_event_triggers(struct trace_array *tr);
1575 struct event_trigger_data {
1576 unsigned long count;
1578 struct event_trigger_ops *ops;
1579 struct event_command *cmd_ops;
1580 struct event_filter __rcu *filter;
1585 struct list_head list;
1587 struct list_head named_list;
1588 struct event_trigger_data *named_data;
1592 #define ENABLE_EVENT_STR "enable_event"
1593 #define DISABLE_EVENT_STR "disable_event"
1594 #define ENABLE_HIST_STR "enable_hist"
1595 #define DISABLE_HIST_STR "disable_hist"
1597 struct enable_trigger_data {
1598 struct trace_event_file *file;
1603 extern int event_enable_trigger_print(struct seq_file *m,
1604 struct event_trigger_ops *ops,
1605 struct event_trigger_data *data);
1606 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1607 struct event_trigger_data *data);
1608 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1609 struct trace_event_file *file,
1610 char *glob, char *cmd, char *param);
1611 extern int event_enable_register_trigger(char *glob,
1612 struct event_trigger_ops *ops,
1613 struct event_trigger_data *data,
1614 struct trace_event_file *file);
1615 extern void event_enable_unregister_trigger(char *glob,
1616 struct event_trigger_ops *ops,
1617 struct event_trigger_data *test,
1618 struct trace_event_file *file);
1619 extern void trigger_data_free(struct event_trigger_data *data);
1620 extern int event_trigger_init(struct event_trigger_ops *ops,
1621 struct event_trigger_data *data);
1622 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1623 int trigger_enable);
1624 extern void update_cond_flag(struct trace_event_file *file);
1625 extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
1626 struct event_trigger_data *test,
1627 struct trace_event_file *file);
1628 extern int set_trigger_filter(char *filter_str,
1629 struct event_trigger_data *trigger_data,
1630 struct trace_event_file *file);
1631 extern struct event_trigger_data *find_named_trigger(const char *name);
1632 extern bool is_named_trigger(struct event_trigger_data *test);
1633 extern int save_named_trigger(const char *name,
1634 struct event_trigger_data *data);
1635 extern void del_named_trigger(struct event_trigger_data *data);
1636 extern void pause_named_trigger(struct event_trigger_data *data);
1637 extern void unpause_named_trigger(struct event_trigger_data *data);
1638 extern void set_named_trigger_data(struct event_trigger_data *data,
1639 struct event_trigger_data *named_data);
1640 extern int register_event_command(struct event_command *cmd);
1641 extern int unregister_event_command(struct event_command *cmd);
1642 extern int register_trigger_hist_enable_disable_cmds(void);
1645 * struct event_trigger_ops - callbacks for trace event triggers
1647 * The methods in this structure provide per-event trigger hooks for
1648 * various trigger operations.
1650 * All the methods below, except for @init() and @free(), must be
1653 * @func: The trigger 'probe' function called when the triggering
1654 * event occurs. The data passed into this callback is the data
1655 * that was supplied to the event_command @reg() function that
1656 * registered the trigger (see struct event_command) along with
1657 * the trace record, rec.
1659 * @init: An optional initialization function called for the trigger
1660 * when the trigger is registered (via the event_command reg()
1661 * function). This can be used to perform per-trigger
1662 * initialization such as incrementing a per-trigger reference
1663 * count, for instance. This is usually implemented by the
1664 * generic utility function @event_trigger_init() (see
1665 * trace_event_triggers.c).
1667 * @free: An optional de-initialization function called for the
1668 * trigger when the trigger is unregistered (via the
1669 * event_command @reg() function). This can be used to perform
1670 * per-trigger de-initialization such as decrementing a
1671 * per-trigger reference count and freeing corresponding trigger
1672 * data, for instance. This is usually implemented by the
1673 * generic utility function @event_trigger_free() (see
1674 * trace_event_triggers.c).
1676 * @print: The callback function invoked to have the trigger print
1677 * itself. This is usually implemented by a wrapper function
1678 * that calls the generic utility function @event_trigger_print()
1679 * (see trace_event_triggers.c).
1681 struct event_trigger_ops {
1682 void (*func)(struct event_trigger_data *data,
1684 int (*init)(struct event_trigger_ops *ops,
1685 struct event_trigger_data *data);
1686 void (*free)(struct event_trigger_ops *ops,
1687 struct event_trigger_data *data);
1688 int (*print)(struct seq_file *m,
1689 struct event_trigger_ops *ops,
1690 struct event_trigger_data *data);
1694 * struct event_command - callbacks and data members for event commands
1696 * Event commands are invoked by users by writing the command name
1697 * into the 'trigger' file associated with a trace event. The
1698 * parameters associated with a specific invocation of an event
1699 * command are used to create an event trigger instance, which is
1700 * added to the list of trigger instances associated with that trace
1701 * event. When the event is hit, the set of triggers associated with
1702 * that event is invoked.
1704 * The data members in this structure provide per-event command data
1705 * for various event commands.
1707 * All the data members below, except for @post_trigger, must be set
1708 * for each event command.
1710 * @name: The unique name that identifies the event command. This is
1711 * the name used when setting triggers via trigger files.
1713 * @trigger_type: A unique id that identifies the event command
1714 * 'type'. This value has two purposes, the first to ensure that
1715 * only one trigger of the same type can be set at a given time
1716 * for a particular event e.g. it doesn't make sense to have both
1717 * a traceon and traceoff trigger attached to a single event at
1718 * the same time, so traceon and traceoff have the same type
1719 * though they have different names. The @trigger_type value is
1720 * also used as a bit value for deferring the actual trigger
1721 * action until after the current event is finished. Some
1722 * commands need to do this if they themselves log to the trace
1723 * buffer (see the @post_trigger() member below). @trigger_type
1724 * values are defined by adding new values to the trigger_type
1725 * enum in include/linux/trace_events.h.
1727 * @flags: See the enum event_command_flags below.
1729 * All the methods below, except for @set_filter() and @unreg_all(),
1730 * must be implemented.
1732 * @func: The callback function responsible for parsing and
1733 * registering the trigger written to the 'trigger' file by the
1734 * user. It allocates the trigger instance and registers it with
1735 * the appropriate trace event. It makes use of the other
1736 * event_command callback functions to orchestrate this, and is
1737 * usually implemented by the generic utility function
1738 * @event_trigger_callback() (see trace_event_triggers.c).
1740 * @reg: Adds the trigger to the list of triggers associated with the
1741 * event, and enables the event trigger itself, after
1742 * initializing it (via the event_trigger_ops @init() function).
1743 * This is also where commands can use the @trigger_type value to
1744 * make the decision as to whether or not multiple instances of
1745 * the trigger should be allowed. This is usually implemented by
1746 * the generic utility function @register_trigger() (see
1747 * trace_event_triggers.c).
1749 * @unreg: Removes the trigger from the list of triggers associated
1750 * with the event, and disables the event trigger itself, after
1751 * initializing it (via the event_trigger_ops @free() function).
1752 * This is usually implemented by the generic utility function
1753 * @unregister_trigger() (see trace_event_triggers.c).
1755 * @unreg_all: An optional function called to remove all the triggers
1756 * from the list of triggers associated with the event. Called
1757 * when a trigger file is opened in truncate mode.
1759 * @set_filter: An optional function called to parse and set a filter
1760 * for the trigger. If no @set_filter() method is set for the
1761 * event command, filters set by the user for the command will be
1762 * ignored. This is usually implemented by the generic utility
1763 * function @set_trigger_filter() (see trace_event_triggers.c).
1765 * @get_trigger_ops: The callback function invoked to retrieve the
1766 * event_trigger_ops implementation associated with the command.
1768 struct event_command {
1769 struct list_head list;
1771 enum event_trigger_type trigger_type;
1773 int (*func)(struct event_command *cmd_ops,
1774 struct trace_event_file *file,
1775 char *glob, char *cmd, char *params);
1776 int (*reg)(char *glob,
1777 struct event_trigger_ops *ops,
1778 struct event_trigger_data *data,
1779 struct trace_event_file *file);
1780 void (*unreg)(char *glob,
1781 struct event_trigger_ops *ops,
1782 struct event_trigger_data *data,
1783 struct trace_event_file *file);
1784 void (*unreg_all)(struct trace_event_file *file);
1785 int (*set_filter)(char *filter_str,
1786 struct event_trigger_data *data,
1787 struct trace_event_file *file);
1788 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1792 * enum event_command_flags - flags for struct event_command
1794 * @POST_TRIGGER: A flag that says whether or not this command needs
1795 * to have its action delayed until after the current event has
1796 * been closed. Some triggers need to avoid being invoked while
1797 * an event is currently in the process of being logged, since
1798 * the trigger may itself log data into the trace buffer. Thus
1799 * we make sure the current event is committed before invoking
1800 * those triggers. To do that, the trigger invocation is split
1801 * in two - the first part checks the filter using the current
1802 * trace record; if a command has the @post_trigger flag set, it
1803 * sets a bit for itself in the return value, otherwise it
1804 * directly invokes the trigger. Once all commands have been
1805 * either invoked or set their return flag, the current record is
1806 * either committed or discarded. At that point, if any commands
1807 * have deferred their triggers, those commands are finally
1808 * invoked following the close of the current event. In other
1809 * words, if the event_trigger_ops @func() probe implementation
1810 * itself logs to the trace buffer, this flag should be set,
1811 * otherwise it can be left unspecified.
1813 * @NEEDS_REC: A flag that says whether or not this command needs
1814 * access to the trace record in order to perform its function,
1815 * regardless of whether or not it has a filter associated with
1816 * it (filters make a trigger require access to the trace record
1817 * but are not always present).
1819 enum event_command_flags {
1820 EVENT_CMD_FL_POST_TRIGGER = 1,
1821 EVENT_CMD_FL_NEEDS_REC = 2,
1824 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1826 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1829 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1831 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1834 extern int trace_event_enable_disable(struct trace_event_file *file,
1835 int enable, int soft_disable);
1836 extern int tracing_alloc_snapshot(void);
1838 extern const char *__start___trace_bprintk_fmt[];
1839 extern const char *__stop___trace_bprintk_fmt[];
1841 extern const char *__start___tracepoint_str[];
1842 extern const char *__stop___tracepoint_str[];
1844 void trace_printk_control(bool enabled);
1845 void trace_printk_init_buffers(void);
1846 void trace_printk_start_comm(void);
1847 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1848 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1851 * Normal trace_printk() and friends allocates special buffers
1852 * to do the manipulation, as well as saves the print formats
1853 * into sections to display. But the trace infrastructure wants
1854 * to use these without the added overhead at the price of being
1855 * a bit slower (used mainly for warnings, where we don't care
1856 * about performance). The internal_trace_puts() is for such
1859 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1862 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1863 extern struct trace_event_call \
1864 __aligned(4) event_##call;
1865 #undef FTRACE_ENTRY_DUP
1866 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1867 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1869 #undef FTRACE_ENTRY_PACKED
1870 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1871 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1874 #include "trace_entries.h"
1876 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1877 int perf_ftrace_event_register(struct trace_event_call *call,
1878 enum trace_reg type, void *data);
1880 #define perf_ftrace_event_register NULL
1883 #ifdef CONFIG_FTRACE_SYSCALLS
1884 void init_ftrace_syscalls(void);
1885 const char *get_syscall_name(int syscall);
1887 static inline void init_ftrace_syscalls(void) { }
1888 static inline const char *get_syscall_name(int syscall)
1894 #ifdef CONFIG_EVENT_TRACING
1895 void trace_event_init(void);
1896 void trace_event_eval_update(struct trace_eval_map **map, int len);
1898 static inline void __init trace_event_init(void) { }
1899 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1902 #ifdef CONFIG_TRACER_SNAPSHOT
1903 void tracing_snapshot_instance(struct trace_array *tr);
1904 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1906 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1907 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1913 extern struct trace_iterator *tracepoint_print_iter;
1916 * Reset the state of the trace_iterator so that it can read consumed data.
1917 * Normally, the trace_iterator is used for reading the data when it is not
1918 * consumed, and must retain state.
1920 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1922 const size_t offset = offsetof(struct trace_iterator, seq);
1925 * Keep gcc from complaining about overwriting more than just one
1926 * member in the structure.
1928 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1933 #endif /* _LINUX_KERNEL_TRACE_H */