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 {
197 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
200 * struct cond_snapshot - conditional snapshot data and callback
202 * The cond_snapshot structure encapsulates a callback function and
203 * data associated with the snapshot for a given tracing instance.
205 * When a snapshot is taken conditionally, by invoking
206 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
207 * passed in turn to the cond_snapshot.update() function. That data
208 * can be compared by the update() implementation with the cond_data
209 * contained wihin the struct cond_snapshot instance associated with
210 * the trace_array. Because the tr->max_lock is held throughout the
211 * update() call, the update() function can directly retrieve the
212 * cond_snapshot and cond_data associated with the per-instance
213 * snapshot associated with the trace_array.
215 * The cond_snapshot.update() implementation can save data to be
216 * associated with the snapshot if it decides to, and returns 'true'
217 * in that case, or it returns 'false' if the conditional snapshot
218 * shouldn't be taken.
220 * The cond_snapshot instance is created and associated with the
221 * user-defined cond_data by tracing_cond_snapshot_enable().
222 * Likewise, the cond_snapshot instance is destroyed and is no longer
223 * associated with the trace instance by
224 * tracing_cond_snapshot_disable().
226 * The method below is required.
228 * @update: When a conditional snapshot is invoked, the update()
229 * callback function is invoked with the tr->max_lock held. The
230 * update() implementation signals whether or not to actually
231 * take the snapshot, by returning 'true' if so, 'false' if no
232 * snapshot should be taken. Because the max_lock is held for
233 * the duration of update(), the implementation is safe to
234 * directly retrieven and save any implementation data it needs
235 * to in association with the snapshot.
237 struct cond_snapshot {
239 cond_update_fn_t update;
243 * The trace array - an array of per-CPU trace arrays. This is the
244 * highest level data structure that individual tracers deal with.
245 * They have on/off state as well:
248 struct list_head list;
250 struct trace_buffer trace_buffer;
251 #ifdef CONFIG_TRACER_MAX_TRACE
253 * The max_buffer is used to snapshot the trace when a maximum
254 * latency is reached, or when the user initiates a snapshot.
255 * Some tracers will use this to store a maximum trace while
256 * it continues examining live traces.
258 * The buffers for the max_buffer are set up the same as the trace_buffer
259 * When a snapshot is taken, the buffer of the max_buffer is swapped
260 * with the buffer of the trace_buffer and the buffers are reset for
261 * the trace_buffer so the tracing can continue.
263 struct trace_buffer max_buffer;
264 bool allocated_snapshot;
266 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
267 unsigned long max_latency;
269 struct trace_pid_list __rcu *filtered_pids;
271 * max_lock is used to protect the swapping of buffers
272 * when taking a max snapshot. The buffers themselves are
273 * protected by per_cpu spinlocks. But the action of the swap
274 * needs its own lock.
276 * This is defined as a arch_spinlock_t in order to help
277 * with performance when lockdep debugging is enabled.
279 * It is also used in other places outside the update_max_tr
280 * so it needs to be defined outside of the
281 * CONFIG_TRACER_MAX_TRACE.
283 arch_spinlock_t max_lock;
285 #ifdef CONFIG_FTRACE_SYSCALLS
286 int sys_refcount_enter;
287 int sys_refcount_exit;
288 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
289 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
296 struct tracer *current_trace;
297 unsigned int trace_flags;
298 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
300 raw_spinlock_t start_lock;
302 struct dentry *options;
303 struct dentry *percpu_dir;
304 struct dentry *event_dir;
305 struct trace_options *topts;
306 struct list_head systems;
307 struct list_head events;
308 struct trace_event_file *trace_marker_file;
309 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
311 #ifdef CONFIG_FUNCTION_TRACER
312 struct ftrace_ops *ops;
313 struct trace_pid_list __rcu *function_pids;
314 #ifdef CONFIG_DYNAMIC_FTRACE
315 /* All of these are protected by the ftrace_lock */
316 struct list_head func_probes;
317 struct list_head mod_trace;
318 struct list_head mod_notrace;
320 /* function tracing enabled */
321 int function_enabled;
323 int time_stamp_abs_ref;
324 struct list_head hist_vars;
325 #ifdef CONFIG_TRACER_SNAPSHOT
326 struct cond_snapshot *cond_snapshot;
331 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
334 extern struct list_head ftrace_trace_arrays;
336 extern struct mutex trace_types_lock;
338 extern int trace_array_get(struct trace_array *tr);
339 extern void trace_array_put(struct trace_array *tr);
341 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
342 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
344 extern bool trace_clock_in_ns(struct trace_array *tr);
347 * The global tracer (top) should be the first trace array added,
348 * but we check the flag anyway.
350 static inline struct trace_array *top_trace_array(void)
352 struct trace_array *tr;
354 if (list_empty(&ftrace_trace_arrays))
357 tr = list_entry(ftrace_trace_arrays.prev,
359 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
363 #define FTRACE_CMP_TYPE(var, type) \
364 __builtin_types_compatible_p(typeof(var), type *)
367 #define IF_ASSIGN(var, entry, etype, id) \
368 if (FTRACE_CMP_TYPE(var, etype)) { \
369 var = (typeof(var))(entry); \
370 WARN_ON(id && (entry)->type != id); \
374 /* Will cause compile errors if type is not found. */
375 extern void __ftrace_bad_type(void);
378 * The trace_assign_type is a verifier that the entry type is
379 * the same as the type being assigned. To add new types simply
380 * add a line with the following format:
382 * IF_ASSIGN(var, ent, type, id);
384 * Where "type" is the trace type that includes the trace_entry
385 * as the "ent" item. And "id" is the trace identifier that is
386 * used in the trace_type enum.
388 * If the type can have more than one id, then use zero.
390 #define trace_assign_type(var, ent) \
392 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
393 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
394 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
395 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
396 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
397 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
398 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
399 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
400 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
401 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
403 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
405 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
406 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
408 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
410 __ftrace_bad_type(); \
414 * An option specific to a tracer. This is a boolean value.
415 * The bit is the bit index that sets its value on the
416 * flags value in struct tracer_flags.
419 const char *name; /* Will appear on the trace_options file */
420 u32 bit; /* Mask assigned in val field in tracer_flags */
424 * The set of specific options for a tracer. Your tracer
425 * have to set the initial value of the flags val.
427 struct tracer_flags {
429 struct tracer_opt *opts;
430 struct tracer *trace;
433 /* Makes more easy to define a tracer opt */
434 #define TRACER_OPT(s, b) .name = #s, .bit = b
437 struct trace_option_dentry {
438 struct tracer_opt *opt;
439 struct tracer_flags *flags;
440 struct trace_array *tr;
441 struct dentry *entry;
445 * struct tracer - a specific tracer and its callbacks to interact with tracefs
446 * @name: the name chosen to select it on the available_tracers file
447 * @init: called when one switches to this tracer (echo name > current_tracer)
448 * @reset: called when one switches to another tracer
449 * @start: called when tracing is unpaused (echo 1 > tracing_on)
450 * @stop: called when tracing is paused (echo 0 > tracing_on)
451 * @update_thresh: called when tracing_thresh is updated
452 * @open: called when the trace file is opened
453 * @pipe_open: called when the trace_pipe file is opened
454 * @close: called when the trace file is released
455 * @pipe_close: called when the trace_pipe file is released
456 * @read: override the default read callback on trace_pipe
457 * @splice_read: override the default splice_read callback on trace_pipe
458 * @selftest: selftest to run on boot (see trace_selftest.c)
459 * @print_headers: override the first lines that describe your columns
460 * @print_line: callback that prints a trace
461 * @set_flag: signals one of your private flags changed (trace_options file)
462 * @flags: your private flags
466 int (*init)(struct trace_array *tr);
467 void (*reset)(struct trace_array *tr);
468 void (*start)(struct trace_array *tr);
469 void (*stop)(struct trace_array *tr);
470 int (*update_thresh)(struct trace_array *tr);
471 void (*open)(struct trace_iterator *iter);
472 void (*pipe_open)(struct trace_iterator *iter);
473 void (*close)(struct trace_iterator *iter);
474 void (*pipe_close)(struct trace_iterator *iter);
475 ssize_t (*read)(struct trace_iterator *iter,
476 struct file *filp, char __user *ubuf,
477 size_t cnt, loff_t *ppos);
478 ssize_t (*splice_read)(struct trace_iterator *iter,
481 struct pipe_inode_info *pipe,
484 #ifdef CONFIG_FTRACE_STARTUP_TEST
485 int (*selftest)(struct tracer *trace,
486 struct trace_array *tr);
488 void (*print_header)(struct seq_file *m);
489 enum print_line_t (*print_line)(struct trace_iterator *iter);
490 /* If you handled the flag setting, return 0 */
491 int (*set_flag)(struct trace_array *tr,
492 u32 old_flags, u32 bit, int set);
493 /* Return 0 if OK with change, else return non-zero */
494 int (*flag_changed)(struct trace_array *tr,
497 struct tracer_flags *flags;
501 bool allow_instances;
502 #ifdef CONFIG_TRACER_MAX_TRACE
505 /* True if tracer cannot be enabled in kernel param */
510 /* Only current can touch trace_recursion */
513 * For function tracing recursion:
514 * The order of these bits are important.
516 * When function tracing occurs, the following steps are made:
517 * If arch does not support a ftrace feature:
518 * call internal function (uses INTERNAL bits) which calls...
519 * If callback is registered to the "global" list, the list
520 * function is called and recursion checks the GLOBAL bits.
521 * then this function calls...
522 * The function callback, which can use the FTRACE bits to
523 * check for recursion.
525 * Now if the arch does not suppport a feature, and it calls
526 * the global list function which calls the ftrace callback
527 * all three of these steps will do a recursion protection.
528 * There's no reason to do one if the previous caller already
529 * did. The recursion that we are protecting against will
530 * go through the same steps again.
532 * To prevent the multiple recursion checks, if a recursion
533 * bit is set that is higher than the MAX bit of the current
534 * check, then we know that the check was made by the previous
535 * caller, and we can skip the current check.
539 TRACE_BUFFER_NMI_BIT,
540 TRACE_BUFFER_IRQ_BIT,
541 TRACE_BUFFER_SIRQ_BIT,
543 /* Start of function recursion bits */
545 TRACE_FTRACE_NMI_BIT,
546 TRACE_FTRACE_IRQ_BIT,
547 TRACE_FTRACE_SIRQ_BIT,
549 /* INTERNAL_BITs must be greater than FTRACE_BITs */
551 TRACE_INTERNAL_NMI_BIT,
552 TRACE_INTERNAL_IRQ_BIT,
553 TRACE_INTERNAL_SIRQ_BIT,
557 * Abuse of the trace_recursion.
558 * As we need a way to maintain state if we are tracing the function
559 * graph in irq because we want to trace a particular function that
560 * was called in irq context but we have irq tracing off. Since this
561 * can only be modified by current, we can reuse trace_recursion.
565 /* Set if the function is in the set_graph_function file */
569 * In the very unlikely case that an interrupt came in
570 * at a start of graph tracing, and we want to trace
571 * the function in that interrupt, the depth can be greater
572 * than zero, because of the preempted start of a previous
573 * trace. In an even more unlikely case, depth could be 2
574 * if a softirq interrupted the start of graph tracing,
575 * followed by an interrupt preempting a start of graph
576 * tracing in the softirq, and depth can even be 3
577 * if an NMI came in at the start of an interrupt function
578 * that preempted a softirq start of a function that
579 * preempted normal context!!!! Luckily, it can't be
580 * greater than 3, so the next two bits are a mask
581 * of what the depth is when we set TRACE_GRAPH_BIT
584 TRACE_GRAPH_DEPTH_START_BIT,
585 TRACE_GRAPH_DEPTH_END_BIT,
588 * To implement set_graph_notrace, if this bit is set, we ignore
589 * function graph tracing of called functions, until the return
590 * function is called to clear it.
592 TRACE_GRAPH_NOTRACE_BIT,
595 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
596 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
597 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
599 #define trace_recursion_depth() \
600 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
601 #define trace_recursion_set_depth(depth) \
603 current->trace_recursion &= \
604 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
605 current->trace_recursion |= \
606 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
609 #define TRACE_CONTEXT_BITS 4
611 #define TRACE_FTRACE_START TRACE_FTRACE_BIT
612 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
614 #define TRACE_LIST_START TRACE_INTERNAL_BIT
615 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
617 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX
619 static __always_inline int trace_get_context_bit(void)
623 if (in_interrupt()) {
637 static __always_inline int trace_test_and_set_recursion(int start, int max)
639 unsigned int val = current->trace_recursion;
642 /* A previous recursion check was made */
643 if ((val & TRACE_CONTEXT_MASK) > max)
646 bit = trace_get_context_bit() + start;
647 if (unlikely(val & (1 << bit)))
651 current->trace_recursion = val;
657 static __always_inline void trace_clear_recursion(int bit)
659 unsigned int val = current->trace_recursion;
668 current->trace_recursion = val;
671 static inline struct ring_buffer_iter *
672 trace_buffer_iter(struct trace_iterator *iter, int cpu)
674 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
677 int tracer_init(struct tracer *t, struct trace_array *tr);
678 int tracing_is_enabled(void);
679 void tracing_reset(struct trace_buffer *buf, int cpu);
680 void tracing_reset_online_cpus(struct trace_buffer *buf);
681 void tracing_reset_current(int cpu);
682 void tracing_reset_all_online_cpus(void);
683 int tracing_open_generic(struct inode *inode, struct file *filp);
684 bool tracing_is_disabled(void);
685 bool tracer_tracing_is_on(struct trace_array *tr);
686 void tracer_tracing_on(struct trace_array *tr);
687 void tracer_tracing_off(struct trace_array *tr);
688 struct dentry *trace_create_file(const char *name,
690 struct dentry *parent,
692 const struct file_operations *fops);
694 struct dentry *tracing_init_dentry(void);
696 struct ring_buffer_event;
698 struct ring_buffer_event *
699 trace_buffer_lock_reserve(struct ring_buffer *buffer,
705 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
706 struct trace_array_cpu *data);
708 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
709 int *ent_cpu, u64 *ent_ts);
711 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
712 struct ring_buffer_event *event);
714 int trace_empty(struct trace_iterator *iter);
716 void *trace_find_next_entry_inc(struct trace_iterator *iter);
718 void trace_init_global_iter(struct trace_iterator *iter);
720 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
722 void trace_function(struct trace_array *tr,
724 unsigned long parent_ip,
725 unsigned long flags, int pc);
726 void trace_graph_function(struct trace_array *tr,
728 unsigned long parent_ip,
729 unsigned long flags, int pc);
730 void trace_latency_header(struct seq_file *m);
731 void trace_default_header(struct seq_file *m);
732 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
733 int trace_empty(struct trace_iterator *iter);
735 void trace_graph_return(struct ftrace_graph_ret *trace);
736 int trace_graph_entry(struct ftrace_graph_ent *trace);
737 void set_graph_array(struct trace_array *tr);
739 void tracing_start_cmdline_record(void);
740 void tracing_stop_cmdline_record(void);
741 void tracing_start_tgid_record(void);
742 void tracing_stop_tgid_record(void);
744 int register_tracer(struct tracer *type);
745 int is_tracing_stopped(void);
747 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
749 extern cpumask_var_t __read_mostly tracing_buffer_mask;
751 #define for_each_tracing_cpu(cpu) \
752 for_each_cpu(cpu, tracing_buffer_mask)
754 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
756 extern unsigned long tracing_thresh;
762 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
764 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
765 struct task_struct *task);
766 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
767 struct task_struct *self,
768 struct task_struct *task);
769 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
770 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
771 int trace_pid_show(struct seq_file *m, void *v);
772 void trace_free_pid_list(struct trace_pid_list *pid_list);
773 int trace_pid_write(struct trace_pid_list *filtered_pids,
774 struct trace_pid_list **new_pid_list,
775 const char __user *ubuf, size_t cnt);
777 #ifdef CONFIG_TRACER_MAX_TRACE
778 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
780 void update_max_tr_single(struct trace_array *tr,
781 struct task_struct *tsk, int cpu);
782 #endif /* CONFIG_TRACER_MAX_TRACE */
784 #ifdef CONFIG_STACKTRACE
785 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
788 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
792 #endif /* CONFIG_STACKTRACE */
794 extern u64 ftrace_now(int cpu);
796 extern void trace_find_cmdline(int pid, char comm[]);
797 extern int trace_find_tgid(int pid);
798 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
800 #ifdef CONFIG_DYNAMIC_FTRACE
801 extern unsigned long ftrace_update_tot_cnt;
802 void ftrace_init_trace_array(struct trace_array *tr);
804 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
806 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
807 extern int DYN_FTRACE_TEST_NAME(void);
808 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
809 extern int DYN_FTRACE_TEST_NAME2(void);
811 extern bool ring_buffer_expanded;
812 extern bool tracing_selftest_disabled;
814 #ifdef CONFIG_FTRACE_STARTUP_TEST
815 extern int trace_selftest_startup_function(struct tracer *trace,
816 struct trace_array *tr);
817 extern int trace_selftest_startup_function_graph(struct tracer *trace,
818 struct trace_array *tr);
819 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
820 struct trace_array *tr);
821 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
822 struct trace_array *tr);
823 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
824 struct trace_array *tr);
825 extern int trace_selftest_startup_wakeup(struct tracer *trace,
826 struct trace_array *tr);
827 extern int trace_selftest_startup_nop(struct tracer *trace,
828 struct trace_array *tr);
829 extern int trace_selftest_startup_branch(struct tracer *trace,
830 struct trace_array *tr);
832 * Tracer data references selftest functions that only occur
833 * on boot up. These can be __init functions. Thus, when selftests
834 * are enabled, then the tracers need to reference __init functions.
836 #define __tracer_data __refdata
838 /* Tracers are seldom changed. Optimize when selftests are disabled. */
839 #define __tracer_data __read_mostly
840 #endif /* CONFIG_FTRACE_STARTUP_TEST */
842 extern void *head_page(struct trace_array_cpu *data);
843 extern unsigned long long ns2usecs(u64 nsec);
845 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
847 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
849 trace_array_vprintk(struct trace_array *tr,
850 unsigned long ip, const char *fmt, va_list args);
851 int trace_array_printk(struct trace_array *tr,
852 unsigned long ip, const char *fmt, ...);
853 int trace_array_printk_buf(struct ring_buffer *buffer,
854 unsigned long ip, const char *fmt, ...);
855 void trace_printk_seq(struct trace_seq *s);
856 enum print_line_t print_trace_line(struct trace_iterator *iter);
858 extern char trace_find_mark(unsigned long long duration);
862 struct ftrace_mod_load {
863 struct list_head list;
870 FTRACE_HASH_FL_MOD = (1 << 0),
874 unsigned long size_bits;
875 struct hlist_head *buckets;
881 struct ftrace_func_entry *
882 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
884 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
886 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
889 /* Standard output formatting function used for function return traces */
890 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
893 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
894 #define TRACE_GRAPH_PRINT_CPU 0x2
895 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
896 #define TRACE_GRAPH_PRINT_PROC 0x8
897 #define TRACE_GRAPH_PRINT_DURATION 0x10
898 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
899 #define TRACE_GRAPH_PRINT_REL_TIME 0x40
900 #define TRACE_GRAPH_PRINT_IRQS 0x80
901 #define TRACE_GRAPH_PRINT_TAIL 0x100
902 #define TRACE_GRAPH_SLEEP_TIME 0x200
903 #define TRACE_GRAPH_GRAPH_TIME 0x400
904 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
905 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
907 extern void ftrace_graph_sleep_time_control(bool enable);
909 #ifdef CONFIG_FUNCTION_PROFILER
910 extern void ftrace_graph_graph_time_control(bool enable);
912 static inline void ftrace_graph_graph_time_control(bool enable) { }
915 extern enum print_line_t
916 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
917 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
919 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
920 extern void graph_trace_open(struct trace_iterator *iter);
921 extern void graph_trace_close(struct trace_iterator *iter);
922 extern int __trace_graph_entry(struct trace_array *tr,
923 struct ftrace_graph_ent *trace,
924 unsigned long flags, int pc);
925 extern void __trace_graph_return(struct trace_array *tr,
926 struct ftrace_graph_ret *trace,
927 unsigned long flags, int pc);
929 #ifdef CONFIG_DYNAMIC_FTRACE
930 extern struct ftrace_hash *ftrace_graph_hash;
931 extern struct ftrace_hash *ftrace_graph_notrace_hash;
933 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
935 unsigned long addr = trace->func;
938 preempt_disable_notrace();
940 if (ftrace_hash_empty(ftrace_graph_hash)) {
945 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
948 * This needs to be cleared on the return functions
949 * when the depth is zero.
951 trace_recursion_set(TRACE_GRAPH_BIT);
952 trace_recursion_set_depth(trace->depth);
955 * If no irqs are to be traced, but a set_graph_function
956 * is set, and called by an interrupt handler, we still
960 trace_recursion_set(TRACE_IRQ_BIT);
962 trace_recursion_clear(TRACE_IRQ_BIT);
967 preempt_enable_notrace();
971 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
973 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
974 trace->depth == trace_recursion_depth())
975 trace_recursion_clear(TRACE_GRAPH_BIT);
978 static inline int ftrace_graph_notrace_addr(unsigned long addr)
982 preempt_disable_notrace();
984 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
987 preempt_enable_notrace();
991 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
996 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1000 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1002 #endif /* CONFIG_DYNAMIC_FTRACE */
1004 extern unsigned int fgraph_max_depth;
1006 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
1008 /* trace it when it is-nested-in or is a function enabled. */
1009 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
1010 ftrace_graph_addr(trace)) ||
1011 (trace->depth < 0) ||
1012 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1015 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1016 static inline enum print_line_t
1017 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1019 return TRACE_TYPE_UNHANDLED;
1021 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1023 extern struct list_head ftrace_pids;
1025 #ifdef CONFIG_FUNCTION_TRACER
1026 struct ftrace_func_command {
1027 struct list_head list;
1029 int (*func)(struct trace_array *tr,
1030 struct ftrace_hash *hash,
1031 char *func, char *cmd,
1032 char *params, int enable);
1034 extern bool ftrace_filter_param __initdata;
1035 static inline int ftrace_trace_task(struct trace_array *tr)
1037 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
1039 extern int ftrace_is_dead(void);
1040 int ftrace_create_function_files(struct trace_array *tr,
1041 struct dentry *parent);
1042 void ftrace_destroy_function_files(struct trace_array *tr);
1043 void ftrace_init_global_array_ops(struct trace_array *tr);
1044 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1045 void ftrace_reset_array_ops(struct trace_array *tr);
1046 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1047 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1048 struct dentry *d_tracer);
1049 void ftrace_clear_pids(struct trace_array *tr);
1050 int init_function_trace(void);
1051 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1053 static inline int ftrace_trace_task(struct trace_array *tr)
1057 static inline int ftrace_is_dead(void) { return 0; }
1059 ftrace_create_function_files(struct trace_array *tr,
1060 struct dentry *parent)
1064 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1065 static inline __init void
1066 ftrace_init_global_array_ops(struct trace_array *tr) { }
1067 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1068 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1069 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1070 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1071 static inline int init_function_trace(void) { return 0; }
1072 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1073 /* ftace_func_t type is not defined, use macro instead of static inline */
1074 #define ftrace_init_array_ops(tr, func) do { } while (0)
1075 #endif /* CONFIG_FUNCTION_TRACER */
1077 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1079 struct ftrace_probe_ops {
1080 void (*func)(unsigned long ip,
1081 unsigned long parent_ip,
1082 struct trace_array *tr,
1083 struct ftrace_probe_ops *ops,
1085 int (*init)(struct ftrace_probe_ops *ops,
1086 struct trace_array *tr,
1087 unsigned long ip, void *init_data,
1089 void (*free)(struct ftrace_probe_ops *ops,
1090 struct trace_array *tr,
1091 unsigned long ip, void *data);
1092 int (*print)(struct seq_file *m,
1094 struct ftrace_probe_ops *ops,
1098 struct ftrace_func_mapper;
1099 typedef int (*ftrace_mapper_func)(void *data);
1101 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1102 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1104 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1105 unsigned long ip, void *data);
1106 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1108 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1109 ftrace_mapper_func free_func);
1112 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1113 struct ftrace_probe_ops *ops, void *data);
1115 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1116 struct ftrace_probe_ops *ops);
1117 extern void clear_ftrace_function_probes(struct trace_array *tr);
1119 int register_ftrace_command(struct ftrace_func_command *cmd);
1120 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1122 void ftrace_create_filter_files(struct ftrace_ops *ops,
1123 struct dentry *parent);
1124 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1126 struct ftrace_func_command;
1128 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1132 static inline __init int unregister_ftrace_command(char *cmd_name)
1136 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1141 * The ops parameter passed in is usually undefined.
1142 * This must be a macro.
1144 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1145 #define ftrace_destroy_filter_files(ops) do { } while (0)
1146 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1148 bool ftrace_event_is_function(struct trace_event_call *call);
1151 * struct trace_parser - servers for reading the user input separated by spaces
1152 * @cont: set if the input is not complete - no final space char was found
1153 * @buffer: holds the parsed user input
1154 * @idx: user input length
1155 * @size: buffer size
1157 struct trace_parser {
1164 static inline bool trace_parser_loaded(struct trace_parser *parser)
1166 return (parser->idx != 0);
1169 static inline bool trace_parser_cont(struct trace_parser *parser)
1171 return parser->cont;
1174 static inline void trace_parser_clear(struct trace_parser *parser)
1176 parser->cont = false;
1180 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1181 extern void trace_parser_put(struct trace_parser *parser);
1182 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1183 size_t cnt, loff_t *ppos);
1186 * Only create function graph options if function graph is configured.
1188 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1189 # define FGRAPH_FLAGS \
1190 C(DISPLAY_GRAPH, "display-graph"),
1192 # define FGRAPH_FLAGS
1195 #ifdef CONFIG_BRANCH_TRACER
1196 # define BRANCH_FLAGS \
1197 C(BRANCH, "branch"),
1199 # define BRANCH_FLAGS
1202 #ifdef CONFIG_FUNCTION_TRACER
1203 # define FUNCTION_FLAGS \
1204 C(FUNCTION, "function-trace"), \
1205 C(FUNC_FORK, "function-fork"),
1206 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1208 # define FUNCTION_FLAGS
1209 # define FUNCTION_DEFAULT_FLAGS 0UL
1210 # define TRACE_ITER_FUNC_FORK 0UL
1213 #ifdef CONFIG_STACKTRACE
1214 # define STACK_FLAGS \
1215 C(STACKTRACE, "stacktrace"),
1217 # define STACK_FLAGS
1221 * trace_iterator_flags is an enumeration that defines bit
1222 * positions into trace_flags that controls the output.
1224 * NOTE: These bits must match the trace_options array in
1225 * trace.c (this macro guarantees it).
1227 #define TRACE_FLAGS \
1228 C(PRINT_PARENT, "print-parent"), \
1229 C(SYM_OFFSET, "sym-offset"), \
1230 C(SYM_ADDR, "sym-addr"), \
1231 C(VERBOSE, "verbose"), \
1235 C(BLOCK, "block"), \
1236 C(PRINTK, "trace_printk"), \
1237 C(ANNOTATE, "annotate"), \
1238 C(USERSTACKTRACE, "userstacktrace"), \
1239 C(SYM_USEROBJ, "sym-userobj"), \
1240 C(PRINTK_MSGONLY, "printk-msg-only"), \
1241 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1242 C(LATENCY_FMT, "latency-format"), \
1243 C(RECORD_CMD, "record-cmd"), \
1244 C(RECORD_TGID, "record-tgid"), \
1245 C(OVERWRITE, "overwrite"), \
1246 C(STOP_ON_FREE, "disable_on_free"), \
1247 C(IRQ_INFO, "irq-info"), \
1248 C(MARKERS, "markers"), \
1249 C(EVENT_FORK, "event-fork"), \
1256 * By defining C, we can make TRACE_FLAGS a list of bit names
1257 * that will define the bits for the flag masks.
1260 #define C(a, b) TRACE_ITER_##a##_BIT
1262 enum trace_iterator_bits {
1264 /* Make sure we don't go more than we have bits for */
1269 * By redefining C, we can make TRACE_FLAGS a list of masks that
1270 * use the bits as defined above.
1273 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1275 enum trace_iterator_flags { TRACE_FLAGS };
1278 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1279 * control the output of kernel symbols.
1281 #define TRACE_ITER_SYM_MASK \
1282 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1284 extern struct tracer nop_trace;
1286 #ifdef CONFIG_BRANCH_TRACER
1287 extern int enable_branch_tracing(struct trace_array *tr);
1288 extern void disable_branch_tracing(void);
1289 static inline int trace_branch_enable(struct trace_array *tr)
1291 if (tr->trace_flags & TRACE_ITER_BRANCH)
1292 return enable_branch_tracing(tr);
1295 static inline void trace_branch_disable(void)
1297 /* due to races, always disable */
1298 disable_branch_tracing();
1301 static inline int trace_branch_enable(struct trace_array *tr)
1305 static inline void trace_branch_disable(void)
1308 #endif /* CONFIG_BRANCH_TRACER */
1310 /* set ring buffers to default size if not already done so */
1311 int tracing_update_buffers(void);
1313 struct ftrace_event_field {
1314 struct list_head link;
1325 struct event_filter {
1326 struct prog_entry __rcu *prog;
1327 char *filter_string;
1330 struct event_subsystem {
1331 struct list_head list;
1333 struct event_filter *filter;
1337 struct trace_subsystem_dir {
1338 struct list_head list;
1339 struct event_subsystem *subsystem;
1340 struct trace_array *tr;
1341 struct dentry *entry;
1346 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1347 struct ring_buffer *buffer,
1348 struct ring_buffer_event *event);
1350 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1351 struct ring_buffer *buffer,
1352 struct ring_buffer_event *event,
1353 unsigned long flags, int pc,
1354 struct pt_regs *regs);
1356 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1357 struct ring_buffer *buffer,
1358 struct ring_buffer_event *event,
1359 unsigned long flags, int pc)
1361 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1364 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1365 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1366 void trace_buffered_event_disable(void);
1367 void trace_buffered_event_enable(void);
1370 __trace_event_discard_commit(struct ring_buffer *buffer,
1371 struct ring_buffer_event *event)
1373 if (this_cpu_read(trace_buffered_event) == event) {
1374 /* Simply release the temp buffer */
1375 this_cpu_dec(trace_buffered_event_cnt);
1378 ring_buffer_discard_commit(buffer, event);
1382 * Helper function for event_trigger_unlock_commit{_regs}().
1383 * If there are event triggers attached to this event that requires
1384 * filtering against its fields, then they wil be called as the
1385 * entry already holds the field information of the current event.
1387 * It also checks if the event should be discarded or not.
1388 * It is to be discarded if the event is soft disabled and the
1389 * event was only recorded to process triggers, or if the event
1390 * filter is active and this event did not match the filters.
1392 * Returns true if the event is discarded, false otherwise.
1395 __event_trigger_test_discard(struct trace_event_file *file,
1396 struct ring_buffer *buffer,
1397 struct ring_buffer_event *event,
1399 enum event_trigger_type *tt)
1401 unsigned long eflags = file->flags;
1403 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1404 *tt = event_triggers_call(file, entry, event);
1406 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1407 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1408 !filter_match_preds(file->filter, entry))) {
1409 __trace_event_discard_commit(buffer, event);
1417 * event_trigger_unlock_commit - handle triggers and finish event commit
1418 * @file: The file pointer assoctiated to the event
1419 * @buffer: The ring buffer that the event is being written to
1420 * @event: The event meta data in the ring buffer
1421 * @entry: The event itself
1422 * @irq_flags: The state of the interrupts at the start of the event
1423 * @pc: The state of the preempt count at the start of the event.
1425 * This is a helper function to handle triggers that require data
1426 * from the event itself. It also tests the event against filters and
1427 * if the event is soft disabled and should be discarded.
1430 event_trigger_unlock_commit(struct trace_event_file *file,
1431 struct ring_buffer *buffer,
1432 struct ring_buffer_event *event,
1433 void *entry, unsigned long irq_flags, int pc)
1435 enum event_trigger_type tt = ETT_NONE;
1437 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1438 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1441 event_triggers_post_call(file, tt);
1445 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1446 * @file: The file pointer assoctiated to the event
1447 * @buffer: The ring buffer that the event is being written to
1448 * @event: The event meta data in the ring buffer
1449 * @entry: The event itself
1450 * @irq_flags: The state of the interrupts at the start of the event
1451 * @pc: The state of the preempt count at the start of the event.
1453 * This is a helper function to handle triggers that require data
1454 * from the event itself. It also tests the event against filters and
1455 * if the event is soft disabled and should be discarded.
1457 * Same as event_trigger_unlock_commit() but calls
1458 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1461 event_trigger_unlock_commit_regs(struct trace_event_file *file,
1462 struct ring_buffer *buffer,
1463 struct ring_buffer_event *event,
1464 void *entry, unsigned long irq_flags, int pc,
1465 struct pt_regs *regs)
1467 enum event_trigger_type tt = ETT_NONE;
1469 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1470 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1471 irq_flags, pc, regs);
1474 event_triggers_post_call(file, tt);
1477 #define FILTER_PRED_INVALID ((unsigned short)-1)
1478 #define FILTER_PRED_IS_RIGHT (1 << 15)
1479 #define FILTER_PRED_FOLD (1 << 15)
1482 * The max preds is the size of unsigned short with
1483 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1484 * and FOLD flags. The other is reserved.
1486 * 2^14 preds is way more than enough.
1488 #define MAX_FILTER_PRED 16384
1493 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1495 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1507 char pattern[MAX_FILTER_STR_VAL];
1510 regex_match_func match;
1513 struct filter_pred {
1514 filter_pred_fn_t fn;
1517 unsigned short *ops;
1518 struct ftrace_event_field *field;
1524 static inline bool is_string_field(struct ftrace_event_field *field)
1526 return field->filter_type == FILTER_DYN_STRING ||
1527 field->filter_type == FILTER_STATIC_STRING ||
1528 field->filter_type == FILTER_PTR_STRING ||
1529 field->filter_type == FILTER_COMM;
1532 static inline bool is_function_field(struct ftrace_event_field *field)
1534 return field->filter_type == FILTER_TRACE_FN;
1537 extern enum regex_type
1538 filter_parse_regex(char *buff, int len, char **search, int *not);
1539 extern void print_event_filter(struct trace_event_file *file,
1540 struct trace_seq *s);
1541 extern int apply_event_filter(struct trace_event_file *file,
1542 char *filter_string);
1543 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1544 char *filter_string);
1545 extern void print_subsystem_event_filter(struct event_subsystem *system,
1546 struct trace_seq *s);
1547 extern int filter_assign_type(const char *type);
1548 extern int create_event_filter(struct trace_event_call *call,
1549 char *filter_str, bool set_str,
1550 struct event_filter **filterp);
1551 extern void free_event_filter(struct event_filter *filter);
1553 struct ftrace_event_field *
1554 trace_find_event_field(struct trace_event_call *call, char *name);
1556 extern void trace_event_enable_cmd_record(bool enable);
1557 extern void trace_event_enable_tgid_record(bool enable);
1559 extern int event_trace_init(void);
1560 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1561 extern int event_trace_del_tracer(struct trace_array *tr);
1563 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1566 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1570 static inline void *event_file_data(struct file *filp)
1572 return READ_ONCE(file_inode(filp)->i_private);
1575 extern struct mutex event_mutex;
1576 extern struct list_head ftrace_events;
1578 extern const struct file_operations event_trigger_fops;
1579 extern const struct file_operations event_hist_fops;
1581 #ifdef CONFIG_HIST_TRIGGERS
1582 extern int register_trigger_hist_cmd(void);
1583 extern int register_trigger_hist_enable_disable_cmds(void);
1585 static inline int register_trigger_hist_cmd(void) { return 0; }
1586 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1589 extern int register_trigger_cmds(void);
1590 extern void clear_event_triggers(struct trace_array *tr);
1592 struct event_trigger_data {
1593 unsigned long count;
1595 struct event_trigger_ops *ops;
1596 struct event_command *cmd_ops;
1597 struct event_filter __rcu *filter;
1602 struct list_head list;
1604 struct list_head named_list;
1605 struct event_trigger_data *named_data;
1609 #define ENABLE_EVENT_STR "enable_event"
1610 #define DISABLE_EVENT_STR "disable_event"
1611 #define ENABLE_HIST_STR "enable_hist"
1612 #define DISABLE_HIST_STR "disable_hist"
1614 struct enable_trigger_data {
1615 struct trace_event_file *file;
1620 extern int event_enable_trigger_print(struct seq_file *m,
1621 struct event_trigger_ops *ops,
1622 struct event_trigger_data *data);
1623 extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1624 struct event_trigger_data *data);
1625 extern int event_enable_trigger_func(struct event_command *cmd_ops,
1626 struct trace_event_file *file,
1627 char *glob, char *cmd, char *param);
1628 extern int event_enable_register_trigger(char *glob,
1629 struct event_trigger_ops *ops,
1630 struct event_trigger_data *data,
1631 struct trace_event_file *file);
1632 extern void event_enable_unregister_trigger(char *glob,
1633 struct event_trigger_ops *ops,
1634 struct event_trigger_data *test,
1635 struct trace_event_file *file);
1636 extern void trigger_data_free(struct event_trigger_data *data);
1637 extern int event_trigger_init(struct event_trigger_ops *ops,
1638 struct event_trigger_data *data);
1639 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1640 int trigger_enable);
1641 extern void update_cond_flag(struct trace_event_file *file);
1642 extern int set_trigger_filter(char *filter_str,
1643 struct event_trigger_data *trigger_data,
1644 struct trace_event_file *file);
1645 extern struct event_trigger_data *find_named_trigger(const char *name);
1646 extern bool is_named_trigger(struct event_trigger_data *test);
1647 extern int save_named_trigger(const char *name,
1648 struct event_trigger_data *data);
1649 extern void del_named_trigger(struct event_trigger_data *data);
1650 extern void pause_named_trigger(struct event_trigger_data *data);
1651 extern void unpause_named_trigger(struct event_trigger_data *data);
1652 extern void set_named_trigger_data(struct event_trigger_data *data,
1653 struct event_trigger_data *named_data);
1654 extern struct event_trigger_data *
1655 get_named_trigger_data(struct event_trigger_data *data);
1656 extern int register_event_command(struct event_command *cmd);
1657 extern int unregister_event_command(struct event_command *cmd);
1658 extern int register_trigger_hist_enable_disable_cmds(void);
1661 * struct event_trigger_ops - callbacks for trace event triggers
1663 * The methods in this structure provide per-event trigger hooks for
1664 * various trigger operations.
1666 * All the methods below, except for @init() and @free(), must be
1669 * @func: The trigger 'probe' function called when the triggering
1670 * event occurs. The data passed into this callback is the data
1671 * that was supplied to the event_command @reg() function that
1672 * registered the trigger (see struct event_command) along with
1673 * the trace record, rec.
1675 * @init: An optional initialization function called for the trigger
1676 * when the trigger is registered (via the event_command reg()
1677 * function). This can be used to perform per-trigger
1678 * initialization such as incrementing a per-trigger reference
1679 * count, for instance. This is usually implemented by the
1680 * generic utility function @event_trigger_init() (see
1681 * trace_event_triggers.c).
1683 * @free: An optional de-initialization function called for the
1684 * trigger when the trigger is unregistered (via the
1685 * event_command @reg() function). This can be used to perform
1686 * per-trigger de-initialization such as decrementing a
1687 * per-trigger reference count and freeing corresponding trigger
1688 * data, for instance. This is usually implemented by the
1689 * generic utility function @event_trigger_free() (see
1690 * trace_event_triggers.c).
1692 * @print: The callback function invoked to have the trigger print
1693 * itself. This is usually implemented by a wrapper function
1694 * that calls the generic utility function @event_trigger_print()
1695 * (see trace_event_triggers.c).
1697 struct event_trigger_ops {
1698 void (*func)(struct event_trigger_data *data,
1700 struct ring_buffer_event *rbe);
1701 int (*init)(struct event_trigger_ops *ops,
1702 struct event_trigger_data *data);
1703 void (*free)(struct event_trigger_ops *ops,
1704 struct event_trigger_data *data);
1705 int (*print)(struct seq_file *m,
1706 struct event_trigger_ops *ops,
1707 struct event_trigger_data *data);
1711 * struct event_command - callbacks and data members for event commands
1713 * Event commands are invoked by users by writing the command name
1714 * into the 'trigger' file associated with a trace event. The
1715 * parameters associated with a specific invocation of an event
1716 * command are used to create an event trigger instance, which is
1717 * added to the list of trigger instances associated with that trace
1718 * event. When the event is hit, the set of triggers associated with
1719 * that event is invoked.
1721 * The data members in this structure provide per-event command data
1722 * for various event commands.
1724 * All the data members below, except for @post_trigger, must be set
1725 * for each event command.
1727 * @name: The unique name that identifies the event command. This is
1728 * the name used when setting triggers via trigger files.
1730 * @trigger_type: A unique id that identifies the event command
1731 * 'type'. This value has two purposes, the first to ensure that
1732 * only one trigger of the same type can be set at a given time
1733 * for a particular event e.g. it doesn't make sense to have both
1734 * a traceon and traceoff trigger attached to a single event at
1735 * the same time, so traceon and traceoff have the same type
1736 * though they have different names. The @trigger_type value is
1737 * also used as a bit value for deferring the actual trigger
1738 * action until after the current event is finished. Some
1739 * commands need to do this if they themselves log to the trace
1740 * buffer (see the @post_trigger() member below). @trigger_type
1741 * values are defined by adding new values to the trigger_type
1742 * enum in include/linux/trace_events.h.
1744 * @flags: See the enum event_command_flags below.
1746 * All the methods below, except for @set_filter() and @unreg_all(),
1747 * must be implemented.
1749 * @func: The callback function responsible for parsing and
1750 * registering the trigger written to the 'trigger' file by the
1751 * user. It allocates the trigger instance and registers it with
1752 * the appropriate trace event. It makes use of the other
1753 * event_command callback functions to orchestrate this, and is
1754 * usually implemented by the generic utility function
1755 * @event_trigger_callback() (see trace_event_triggers.c).
1757 * @reg: Adds the trigger to the list of triggers associated with the
1758 * event, and enables the event trigger itself, after
1759 * initializing it (via the event_trigger_ops @init() function).
1760 * This is also where commands can use the @trigger_type value to
1761 * make the decision as to whether or not multiple instances of
1762 * the trigger should be allowed. This is usually implemented by
1763 * the generic utility function @register_trigger() (see
1764 * trace_event_triggers.c).
1766 * @unreg: Removes the trigger from the list of triggers associated
1767 * with the event, and disables the event trigger itself, after
1768 * initializing it (via the event_trigger_ops @free() function).
1769 * This is usually implemented by the generic utility function
1770 * @unregister_trigger() (see trace_event_triggers.c).
1772 * @unreg_all: An optional function called to remove all the triggers
1773 * from the list of triggers associated with the event. Called
1774 * when a trigger file is opened in truncate mode.
1776 * @set_filter: An optional function called to parse and set a filter
1777 * for the trigger. If no @set_filter() method is set for the
1778 * event command, filters set by the user for the command will be
1779 * ignored. This is usually implemented by the generic utility
1780 * function @set_trigger_filter() (see trace_event_triggers.c).
1782 * @get_trigger_ops: The callback function invoked to retrieve the
1783 * event_trigger_ops implementation associated with the command.
1785 struct event_command {
1786 struct list_head list;
1788 enum event_trigger_type trigger_type;
1790 int (*func)(struct event_command *cmd_ops,
1791 struct trace_event_file *file,
1792 char *glob, char *cmd, char *params);
1793 int (*reg)(char *glob,
1794 struct event_trigger_ops *ops,
1795 struct event_trigger_data *data,
1796 struct trace_event_file *file);
1797 void (*unreg)(char *glob,
1798 struct event_trigger_ops *ops,
1799 struct event_trigger_data *data,
1800 struct trace_event_file *file);
1801 void (*unreg_all)(struct trace_event_file *file);
1802 int (*set_filter)(char *filter_str,
1803 struct event_trigger_data *data,
1804 struct trace_event_file *file);
1805 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1809 * enum event_command_flags - flags for struct event_command
1811 * @POST_TRIGGER: A flag that says whether or not this command needs
1812 * to have its action delayed until after the current event has
1813 * been closed. Some triggers need to avoid being invoked while
1814 * an event is currently in the process of being logged, since
1815 * the trigger may itself log data into the trace buffer. Thus
1816 * we make sure the current event is committed before invoking
1817 * those triggers. To do that, the trigger invocation is split
1818 * in two - the first part checks the filter using the current
1819 * trace record; if a command has the @post_trigger flag set, it
1820 * sets a bit for itself in the return value, otherwise it
1821 * directly invokes the trigger. Once all commands have been
1822 * either invoked or set their return flag, the current record is
1823 * either committed or discarded. At that point, if any commands
1824 * have deferred their triggers, those commands are finally
1825 * invoked following the close of the current event. In other
1826 * words, if the event_trigger_ops @func() probe implementation
1827 * itself logs to the trace buffer, this flag should be set,
1828 * otherwise it can be left unspecified.
1830 * @NEEDS_REC: A flag that says whether or not this command needs
1831 * access to the trace record in order to perform its function,
1832 * regardless of whether or not it has a filter associated with
1833 * it (filters make a trigger require access to the trace record
1834 * but are not always present).
1836 enum event_command_flags {
1837 EVENT_CMD_FL_POST_TRIGGER = 1,
1838 EVENT_CMD_FL_NEEDS_REC = 2,
1841 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1843 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1846 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1848 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1851 extern int trace_event_enable_disable(struct trace_event_file *file,
1852 int enable, int soft_disable);
1853 extern int tracing_alloc_snapshot(void);
1854 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1855 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1857 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1858 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1860 extern const char *__start___trace_bprintk_fmt[];
1861 extern const char *__stop___trace_bprintk_fmt[];
1863 extern const char *__start___tracepoint_str[];
1864 extern const char *__stop___tracepoint_str[];
1866 void trace_printk_control(bool enabled);
1867 void trace_printk_init_buffers(void);
1868 void trace_printk_start_comm(void);
1869 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1870 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1872 #define MAX_EVENT_NAME_LEN 64
1874 extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1875 extern ssize_t trace_parse_run_command(struct file *file,
1876 const char __user *buffer, size_t count, loff_t *ppos,
1877 int (*createfn)(int, char**));
1880 * Normal trace_printk() and friends allocates special buffers
1881 * to do the manipulation, as well as saves the print formats
1882 * into sections to display. But the trace infrastructure wants
1883 * to use these without the added overhead at the price of being
1884 * a bit slower (used mainly for warnings, where we don't care
1885 * about performance). The internal_trace_puts() is for such
1888 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1891 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1892 extern struct trace_event_call \
1893 __aligned(4) event_##call;
1894 #undef FTRACE_ENTRY_DUP
1895 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1896 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1898 #undef FTRACE_ENTRY_PACKED
1899 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1900 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1903 #include "trace_entries.h"
1905 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1906 int perf_ftrace_event_register(struct trace_event_call *call,
1907 enum trace_reg type, void *data);
1909 #define perf_ftrace_event_register NULL
1912 #ifdef CONFIG_FTRACE_SYSCALLS
1913 void init_ftrace_syscalls(void);
1914 const char *get_syscall_name(int syscall);
1916 static inline void init_ftrace_syscalls(void) { }
1917 static inline const char *get_syscall_name(int syscall)
1923 #ifdef CONFIG_EVENT_TRACING
1924 void trace_event_init(void);
1925 void trace_event_eval_update(struct trace_eval_map **map, int len);
1927 static inline void __init trace_event_init(void) { }
1928 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1931 #ifdef CONFIG_TRACER_SNAPSHOT
1932 void tracing_snapshot_instance(struct trace_array *tr);
1933 int tracing_alloc_snapshot_instance(struct trace_array *tr);
1935 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1936 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1942 #ifdef CONFIG_PREEMPT_TRACER
1943 void tracer_preempt_on(unsigned long a0, unsigned long a1);
1944 void tracer_preempt_off(unsigned long a0, unsigned long a1);
1946 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1947 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1949 #ifdef CONFIG_IRQSOFF_TRACER
1950 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1951 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1953 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1954 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1957 extern struct trace_iterator *tracepoint_print_iter;
1959 #endif /* _LINUX_KERNEL_TRACE_H */