1 // SPDX-License-Identifier: GPL-2.0
3 * trace_events_trigger - trace event triggers
5 * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com>
8 #include <linux/security.h>
9 #include <linux/module.h>
10 #include <linux/ctype.h>
11 #include <linux/mutex.h>
12 #include <linux/slab.h>
13 #include <linux/rculist.h>
17 static LIST_HEAD(trigger_commands);
18 static DEFINE_MUTEX(trigger_cmd_mutex);
20 void trigger_data_free(struct event_trigger_data *data)
22 if (data->cmd_ops->set_filter)
23 data->cmd_ops->set_filter(NULL, data, NULL);
25 /* make sure current triggers exit before free */
26 tracepoint_synchronize_unregister();
32 * event_triggers_call - Call triggers associated with a trace event
33 * @file: The trace_event_file associated with the event
34 * @rec: The trace entry for the event, NULL for unconditional invocation
36 * For each trigger associated with an event, invoke the trigger
37 * function registered with the associated trigger command. If rec is
38 * non-NULL, it means that the trigger requires further processing and
39 * shouldn't be unconditionally invoked. If rec is non-NULL and the
40 * trigger has a filter associated with it, rec will checked against
41 * the filter and if the record matches the trigger will be invoked.
42 * If the trigger is a 'post_trigger', meaning it shouldn't be invoked
43 * in any case until the current event is written, the trigger
44 * function isn't invoked but the bit associated with the deferred
45 * trigger is set in the return value.
47 * Returns an enum event_trigger_type value containing a set bit for
48 * any trigger that should be deferred, ETT_NONE if nothing to defer.
50 * Called from tracepoint handlers (with rcu_read_lock_sched() held).
52 * Return: an enum event_trigger_type value containing a set bit for
53 * any trigger that should be deferred, ETT_NONE if nothing to defer.
55 enum event_trigger_type
56 event_triggers_call(struct trace_event_file *file,
57 struct trace_buffer *buffer, void *rec,
58 struct ring_buffer_event *event)
60 struct event_trigger_data *data;
61 enum event_trigger_type tt = ETT_NONE;
62 struct event_filter *filter;
64 if (list_empty(&file->triggers))
67 list_for_each_entry_rcu(data, &file->triggers, list) {
71 data->ops->trigger(data, buffer, rec, event);
74 filter = rcu_dereference_sched(data->filter);
75 if (filter && !filter_match_preds(filter, rec))
77 if (event_command_post_trigger(data->cmd_ops)) {
78 tt |= data->cmd_ops->trigger_type;
81 data->ops->trigger(data, buffer, rec, event);
85 EXPORT_SYMBOL_GPL(event_triggers_call);
87 bool __trace_trigger_soft_disabled(struct trace_event_file *file)
89 unsigned long eflags = file->flags;
91 if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
92 event_triggers_call(file, NULL, NULL, NULL);
93 if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
95 if (eflags & EVENT_FILE_FL_PID_FILTER)
96 return trace_event_ignore_this_pid(file);
99 EXPORT_SYMBOL_GPL(__trace_trigger_soft_disabled);
102 * event_triggers_post_call - Call 'post_triggers' for a trace event
103 * @file: The trace_event_file associated with the event
104 * @tt: enum event_trigger_type containing a set bit for each trigger to invoke
106 * For each trigger associated with an event, invoke the trigger
107 * function registered with the associated trigger command, if the
108 * corresponding bit is set in the tt enum passed into this function.
109 * See @event_triggers_call for details on how those bits are set.
111 * Called from tracepoint handlers (with rcu_read_lock_sched() held).
114 event_triggers_post_call(struct trace_event_file *file,
115 enum event_trigger_type tt)
117 struct event_trigger_data *data;
119 list_for_each_entry_rcu(data, &file->triggers, list) {
122 if (data->cmd_ops->trigger_type & tt)
123 data->ops->trigger(data, NULL, NULL, NULL);
126 EXPORT_SYMBOL_GPL(event_triggers_post_call);
128 #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL)
130 static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
132 struct trace_event_file *event_file = event_file_data(m->private);
134 if (t == SHOW_AVAILABLE_TRIGGERS) {
138 return seq_list_next(t, &event_file->triggers, pos);
141 static bool check_user_trigger(struct trace_event_file *file)
143 struct event_trigger_data *data;
145 list_for_each_entry_rcu(data, &file->triggers, list,
146 lockdep_is_held(&event_mutex)) {
147 if (data->flags & EVENT_TRIGGER_FL_PROBE)
154 static void *trigger_start(struct seq_file *m, loff_t *pos)
156 struct trace_event_file *event_file;
158 /* ->stop() is called even if ->start() fails */
159 mutex_lock(&event_mutex);
160 event_file = event_file_data(m->private);
161 if (unlikely(!event_file))
162 return ERR_PTR(-ENODEV);
164 if (list_empty(&event_file->triggers) || !check_user_trigger(event_file))
165 return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL;
167 return seq_list_start(&event_file->triggers, *pos);
170 static void trigger_stop(struct seq_file *m, void *t)
172 mutex_unlock(&event_mutex);
175 static int trigger_show(struct seq_file *m, void *v)
177 struct event_trigger_data *data;
178 struct event_command *p;
180 if (v == SHOW_AVAILABLE_TRIGGERS) {
181 seq_puts(m, "# Available triggers:\n");
183 mutex_lock(&trigger_cmd_mutex);
184 list_for_each_entry_reverse(p, &trigger_commands, list)
185 seq_printf(m, " %s", p->name);
187 mutex_unlock(&trigger_cmd_mutex);
191 data = list_entry(v, struct event_trigger_data, list);
192 data->ops->print(m, data);
197 static const struct seq_operations event_triggers_seq_ops = {
198 .start = trigger_start,
199 .next = trigger_next,
200 .stop = trigger_stop,
201 .show = trigger_show,
204 static int event_trigger_regex_open(struct inode *inode, struct file *file)
208 ret = security_locked_down(LOCKDOWN_TRACEFS);
212 mutex_lock(&event_mutex);
214 if (unlikely(!event_file_data(file))) {
215 mutex_unlock(&event_mutex);
219 if ((file->f_mode & FMODE_WRITE) &&
220 (file->f_flags & O_TRUNC)) {
221 struct trace_event_file *event_file;
222 struct event_command *p;
224 event_file = event_file_data(file);
226 list_for_each_entry(p, &trigger_commands, list) {
228 p->unreg_all(event_file);
232 if (file->f_mode & FMODE_READ) {
233 ret = seq_open(file, &event_triggers_seq_ops);
235 struct seq_file *m = file->private_data;
240 mutex_unlock(&event_mutex);
245 int trigger_process_regex(struct trace_event_file *file, char *buff)
247 char *command, *next;
248 struct event_command *p;
251 next = buff = skip_spaces(buff);
252 command = strsep(&next, ": \t");
254 next = skip_spaces(next);
258 command = (command[0] != '!') ? command : command + 1;
260 mutex_lock(&trigger_cmd_mutex);
261 list_for_each_entry(p, &trigger_commands, list) {
262 if (strcmp(p->name, command) == 0) {
263 ret = p->parse(p, file, buff, command, next);
268 mutex_unlock(&trigger_cmd_mutex);
273 static ssize_t event_trigger_regex_write(struct file *file,
274 const char __user *ubuf,
275 size_t cnt, loff_t *ppos)
277 struct trace_event_file *event_file;
284 if (cnt >= PAGE_SIZE)
287 buf = memdup_user_nul(ubuf, cnt);
293 mutex_lock(&event_mutex);
294 event_file = event_file_data(file);
295 if (unlikely(!event_file)) {
296 mutex_unlock(&event_mutex);
300 ret = trigger_process_regex(event_file, buf);
301 mutex_unlock(&event_mutex);
313 static int event_trigger_regex_release(struct inode *inode, struct file *file)
315 mutex_lock(&event_mutex);
317 if (file->f_mode & FMODE_READ)
318 seq_release(inode, file);
320 mutex_unlock(&event_mutex);
326 event_trigger_write(struct file *filp, const char __user *ubuf,
327 size_t cnt, loff_t *ppos)
329 return event_trigger_regex_write(filp, ubuf, cnt, ppos);
333 event_trigger_open(struct inode *inode, struct file *filp)
335 /* Checks for tracefs lockdown */
336 return event_trigger_regex_open(inode, filp);
340 event_trigger_release(struct inode *inode, struct file *file)
342 return event_trigger_regex_release(inode, file);
345 const struct file_operations event_trigger_fops = {
346 .open = event_trigger_open,
348 .write = event_trigger_write,
349 .llseek = tracing_lseek,
350 .release = event_trigger_release,
354 * Currently we only register event commands from __init, so mark this
357 __init int register_event_command(struct event_command *cmd)
359 struct event_command *p;
362 mutex_lock(&trigger_cmd_mutex);
363 list_for_each_entry(p, &trigger_commands, list) {
364 if (strcmp(cmd->name, p->name) == 0) {
369 list_add(&cmd->list, &trigger_commands);
371 mutex_unlock(&trigger_cmd_mutex);
377 * Currently we only unregister event commands from __init, so mark
380 __init int unregister_event_command(struct event_command *cmd)
382 struct event_command *p, *n;
385 mutex_lock(&trigger_cmd_mutex);
386 list_for_each_entry_safe(p, n, &trigger_commands, list) {
387 if (strcmp(cmd->name, p->name) == 0) {
389 list_del_init(&p->list);
394 mutex_unlock(&trigger_cmd_mutex);
400 * event_trigger_print - Generic event_trigger_ops @print implementation
401 * @name: The name of the event trigger
402 * @m: The seq_file being printed to
403 * @data: Trigger-specific data
404 * @filter_str: filter_str to print, if present
406 * Common implementation for event triggers to print themselves.
408 * Usually wrapped by a function that simply sets the @name of the
409 * trigger command and then invokes this.
411 * Return: 0 on success, errno otherwise
414 event_trigger_print(const char *name, struct seq_file *m,
415 void *data, char *filter_str)
417 long count = (long)data;
422 seq_puts(m, ":unlimited");
424 seq_printf(m, ":count=%ld", count);
427 seq_printf(m, " if %s\n", filter_str);
435 * event_trigger_init - Generic event_trigger_ops @init implementation
436 * @data: Trigger-specific data
438 * Common implementation of event trigger initialization.
440 * Usually used directly as the @init method in event trigger
443 * Return: 0 on success, errno otherwise
445 int event_trigger_init(struct event_trigger_data *data)
452 * event_trigger_free - Generic event_trigger_ops @free implementation
453 * @data: Trigger-specific data
455 * Common implementation of event trigger de-initialization.
457 * Usually used directly as the @free method in event trigger
461 event_trigger_free(struct event_trigger_data *data)
463 if (WARN_ON_ONCE(data->ref <= 0))
468 trigger_data_free(data);
471 int trace_event_trigger_enable_disable(struct trace_event_file *file,
476 if (trigger_enable) {
477 if (atomic_inc_return(&file->tm_ref) > 1)
479 set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags);
480 ret = trace_event_enable_disable(file, 1, 1);
482 if (atomic_dec_return(&file->tm_ref) > 0)
484 clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags);
485 ret = trace_event_enable_disable(file, 0, 1);
492 * clear_event_triggers - Clear all triggers associated with a trace array
493 * @tr: The trace array to clear
495 * For each trigger, the triggering event has its tm_ref decremented
496 * via trace_event_trigger_enable_disable(), and any associated event
497 * (in the case of enable/disable_event triggers) will have its sm_ref
498 * decremented via free()->trace_event_enable_disable(). That
499 * combination effectively reverses the soft-mode/trigger state added
500 * by trigger registration.
502 * Must be called with event_mutex held.
505 clear_event_triggers(struct trace_array *tr)
507 struct trace_event_file *file;
509 list_for_each_entry(file, &tr->events, list) {
510 struct event_trigger_data *data, *n;
511 list_for_each_entry_safe(data, n, &file->triggers, list) {
512 trace_event_trigger_enable_disable(file, 0);
513 list_del_rcu(&data->list);
515 data->ops->free(data);
521 * update_cond_flag - Set or reset the TRIGGER_COND bit
522 * @file: The trace_event_file associated with the event
524 * If an event has triggers and any of those triggers has a filter or
525 * a post_trigger, trigger invocation needs to be deferred until after
526 * the current event has logged its data, and the event should have
527 * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be
530 void update_cond_flag(struct trace_event_file *file)
532 struct event_trigger_data *data;
533 bool set_cond = false;
535 lockdep_assert_held(&event_mutex);
537 list_for_each_entry(data, &file->triggers, list) {
538 if (data->filter || event_command_post_trigger(data->cmd_ops) ||
539 event_command_needs_rec(data->cmd_ops)) {
546 set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags);
548 clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags);
552 * register_trigger - Generic event_command @reg implementation
553 * @glob: The raw string used to register the trigger
554 * @data: Trigger-specific data to associate with the trigger
555 * @file: The trace_event_file associated with the event
557 * Common implementation for event trigger registration.
559 * Usually used directly as the @reg method in event command
562 * Return: 0 on success, errno otherwise
564 static int register_trigger(char *glob,
565 struct event_trigger_data *data,
566 struct trace_event_file *file)
568 struct event_trigger_data *test;
571 lockdep_assert_held(&event_mutex);
573 list_for_each_entry(test, &file->triggers, list) {
574 if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) {
580 if (data->ops->init) {
581 ret = data->ops->init(data);
586 list_add_rcu(&data->list, &file->triggers);
588 update_cond_flag(file);
589 ret = trace_event_trigger_enable_disable(file, 1);
591 list_del_rcu(&data->list);
592 update_cond_flag(file);
599 * unregister_trigger - Generic event_command @unreg implementation
600 * @glob: The raw string used to register the trigger
601 * @test: Trigger-specific data used to find the trigger to remove
602 * @file: The trace_event_file associated with the event
604 * Common implementation for event trigger unregistration.
606 * Usually used directly as the @unreg method in event command
609 static void unregister_trigger(char *glob,
610 struct event_trigger_data *test,
611 struct trace_event_file *file)
613 struct event_trigger_data *data = NULL, *iter;
615 lockdep_assert_held(&event_mutex);
617 list_for_each_entry(iter, &file->triggers, list) {
618 if (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) {
620 list_del_rcu(&data->list);
621 trace_event_trigger_enable_disable(file, 0);
622 update_cond_flag(file);
627 if (data && data->ops->free)
628 data->ops->free(data);
632 * Event trigger parsing helper functions.
634 * These functions help make it easier to write an event trigger
635 * parsing function i.e. the struct event_command.parse() callback
636 * function responsible for parsing and registering a trigger command
637 * written to the 'trigger' file.
639 * A trigger command (or just 'trigger' for short) takes the form:
640 * [trigger] [if filter]
642 * The struct event_command.parse() callback (and other struct
643 * event_command functions) refer to several components of a trigger
644 * command. Those same components are referenced by the event trigger
645 * parsing helper functions defined below. These components are:
647 * cmd - the trigger command name
648 * glob - the trigger command name optionally prefaced with '!'
649 * param_and_filter - text following cmd and ':'
650 * param - text following cmd and ':' and stripped of filter
651 * filter - the optional filter text following (and including) 'if'
653 * To illustrate the use of these componenents, here are some concrete
654 * examples. For the following triggers:
656 * echo 'traceon:5 if pid == 0' > trigger
657 * - 'traceon' is both cmd and glob
658 * - '5 if pid == 0' is the param_and_filter
660 * - 'if pid == 0' is the filter
662 * echo 'enable_event:sys:event:n' > trigger
663 * - 'enable_event' is both cmd and glob
664 * - 'sys:event:n' is the param_and_filter
665 * - 'sys:event:n' is the param
666 * - there is no filter
668 * echo 'hist:keys=pid if prio > 50' > trigger
669 * - 'hist' is both cmd and glob
670 * - 'keys=pid if prio > 50' is the param_and_filter
671 * - 'keys=pid' is the param
672 * - 'if prio > 50' is the filter
674 * echo '!enable_event:sys:event:n' > trigger
675 * - 'enable_event' the cmd
676 * - '!enable_event' is the glob
677 * - 'sys:event:n' is the param_and_filter
678 * - 'sys:event:n' is the param
679 * - there is no filter
681 * echo 'traceoff' > trigger
682 * - 'traceoff' is both cmd and glob
683 * - there is no param_and_filter
684 * - there is no param
685 * - there is no filter
687 * There are a few different categories of event trigger covered by
690 * - triggers that don't require a parameter e.g. traceon
691 * - triggers that do require a parameter e.g. enable_event and hist
692 * - triggers that though they may not require a param may support an
693 * optional 'n' param (n = number of times the trigger should fire)
694 * e.g.: traceon:5 or enable_event:sys:event:n
695 * - triggers that do not support an 'n' param e.g. hist
697 * These functions can be used or ignored as necessary - it all
698 * depends on the complexity of the trigger, and the granularity of
699 * the functions supported reflects the fact that some implementations
700 * may need to customize certain aspects of their implementations and
701 * won't need certain functions. For instance, the hist trigger
702 * implementation doesn't use event_trigger_separate_filter() because
703 * it has special requirements for handling the filter.
707 * event_trigger_check_remove - check whether an event trigger specifies remove
708 * @glob: The trigger command string, with optional remove(!) operator
710 * The event trigger callback implementations pass in 'glob' as a
711 * parameter. This is the command name either with or without a
712 * remove(!) operator. This function simply parses the glob and
713 * determines whether the command corresponds to a trigger removal or
714 * a trigger addition.
716 * Return: true if this is a remove command, false otherwise
718 bool event_trigger_check_remove(const char *glob)
720 return (glob && glob[0] == '!') ? true : false;
724 * event_trigger_empty_param - check whether the param is empty
725 * @param: The trigger param string
727 * The event trigger callback implementations pass in 'param' as a
728 * parameter. This corresponds to the string following the command
729 * name minus the command name. This function can be called by a
730 * callback implementation for any command that requires a param; a
731 * callback that doesn't require a param can ignore it.
733 * Return: true if this is an empty param, false otherwise
735 bool event_trigger_empty_param(const char *param)
741 * event_trigger_separate_filter - separate an event trigger from a filter
742 * @param_and_filter: String containing trigger and possibly filter
743 * @param: outparam, will be filled with a pointer to the trigger
744 * @filter: outparam, will be filled with a pointer to the filter
745 * @param_required: Specifies whether or not the param string is required
747 * Given a param string of the form '[trigger] [if filter]', this
748 * function separates the filter from the trigger and returns the
749 * trigger in @param and the filter in @filter. Either the @param
750 * or the @filter may be set to NULL by this function - if not set to
751 * NULL, they will contain strings corresponding to the trigger and
754 * There are two cases that need to be handled with respect to the
755 * passed-in param: either the param is required, or it is not
756 * required. If @param_required is set, and there's no param, it will
757 * return -EINVAL. If @param_required is not set and there's a param
758 * that starts with a number, that corresponds to the case of a
759 * trigger with :n (n = number of times the trigger should fire) and
760 * the parsing continues normally; otherwise the function just returns
761 * and assumes param just contains a filter and there's nothing else
764 * Return: 0 on success, errno otherwise
766 int event_trigger_separate_filter(char *param_and_filter, char **param,
767 char **filter, bool param_required)
771 *param = *filter = NULL;
773 if (!param_and_filter) {
780 * Here we check for an optional param. The only legal
781 * optional param is :n, and if that's the case, continue
782 * below. Otherwise we assume what's left is a filter and
783 * return it as the filter string for the caller to deal with.
785 if (!param_required && param_and_filter && !isdigit(param_and_filter[0])) {
786 *filter = param_and_filter;
791 * Separate the param from the filter (param [if filter]).
792 * Here we have either an optional :n param or a required
793 * param and an optional filter.
795 *param = strsep(¶m_and_filter, " \t");
798 * Here we have a filter, though it may be empty.
800 if (param_and_filter) {
801 *filter = skip_spaces(param_and_filter);
810 * event_trigger_alloc - allocate and init event_trigger_data for a trigger
811 * @cmd_ops: The event_command operations for the trigger
812 * @cmd: The cmd string
813 * @param: The param string
814 * @private_data: User data to associate with the event trigger
816 * Allocate an event_trigger_data instance and initialize it. The
817 * @cmd_ops are used along with the @cmd and @param to get the
818 * trigger_ops to assign to the event_trigger_data. @private_data can
819 * also be passed in and associated with the event_trigger_data.
821 * Use event_trigger_free() to free an event_trigger_data object.
823 * Return: The trigger_data object success, NULL otherwise
825 struct event_trigger_data *event_trigger_alloc(struct event_command *cmd_ops,
830 struct event_trigger_data *trigger_data;
831 struct event_trigger_ops *trigger_ops;
833 trigger_ops = cmd_ops->get_trigger_ops(cmd, param);
835 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
839 trigger_data->count = -1;
840 trigger_data->ops = trigger_ops;
841 trigger_data->cmd_ops = cmd_ops;
842 trigger_data->private_data = private_data;
844 INIT_LIST_HEAD(&trigger_data->list);
845 INIT_LIST_HEAD(&trigger_data->named_list);
846 RCU_INIT_POINTER(trigger_data->filter, NULL);
852 * event_trigger_parse_num - parse and return the number param for a trigger
853 * @param: The param string
854 * @trigger_data: The trigger_data for the trigger
856 * Parse the :n (n = number of times the trigger should fire) param
857 * and set the count variable in the trigger_data to the parsed count.
859 * Return: 0 on success, errno otherwise
861 int event_trigger_parse_num(char *param,
862 struct event_trigger_data *trigger_data)
868 number = strsep(¶m, ":");
874 * We use the callback data field (which is a pointer)
877 ret = kstrtoul(number, 0, &trigger_data->count);
884 * event_trigger_set_filter - set an event trigger's filter
885 * @cmd_ops: The event_command operations for the trigger
886 * @file: The event file for the trigger's event
887 * @param: The string containing the filter
888 * @trigger_data: The trigger_data for the trigger
890 * Set the filter for the trigger. If the filter is NULL, just return
893 * Return: 0 on success, errno otherwise
895 int event_trigger_set_filter(struct event_command *cmd_ops,
896 struct trace_event_file *file,
898 struct event_trigger_data *trigger_data)
900 if (param && cmd_ops->set_filter)
901 return cmd_ops->set_filter(param, trigger_data, file);
907 * event_trigger_reset_filter - reset an event trigger's filter
908 * @cmd_ops: The event_command operations for the trigger
909 * @trigger_data: The trigger_data for the trigger
911 * Reset the filter for the trigger to no filter.
913 void event_trigger_reset_filter(struct event_command *cmd_ops,
914 struct event_trigger_data *trigger_data)
916 if (cmd_ops->set_filter)
917 cmd_ops->set_filter(NULL, trigger_data, NULL);
921 * event_trigger_register - register an event trigger
922 * @cmd_ops: The event_command operations for the trigger
923 * @file: The event file for the trigger's event
924 * @glob: The trigger command string, with optional remove(!) operator
925 * @trigger_data: The trigger_data for the trigger
927 * Register an event trigger. The @cmd_ops are used to call the
928 * cmd_ops->reg() function which actually does the registration.
930 * Return: 0 on success, errno otherwise
932 int event_trigger_register(struct event_command *cmd_ops,
933 struct trace_event_file *file,
935 struct event_trigger_data *trigger_data)
937 return cmd_ops->reg(glob, trigger_data, file);
941 * event_trigger_unregister - unregister an event trigger
942 * @cmd_ops: The event_command operations for the trigger
943 * @file: The event file for the trigger's event
944 * @glob: The trigger command string, with optional remove(!) operator
945 * @trigger_data: The trigger_data for the trigger
947 * Unregister an event trigger. The @cmd_ops are used to call the
948 * cmd_ops->unreg() function which actually does the unregistration.
950 void event_trigger_unregister(struct event_command *cmd_ops,
951 struct trace_event_file *file,
953 struct event_trigger_data *trigger_data)
955 cmd_ops->unreg(glob, trigger_data, file);
959 * End event trigger parsing helper functions.
963 * event_trigger_parse - Generic event_command @parse implementation
964 * @cmd_ops: The command ops, used for trigger registration
965 * @file: The trace_event_file associated with the event
966 * @glob: The raw string used to register the trigger
967 * @cmd: The cmd portion of the string used to register the trigger
968 * @param_and_filter: The param and filter portion of the string used to register the trigger
970 * Common implementation for event command parsing and trigger
973 * Usually used directly as the @parse method in event command
976 * Return: 0 on success, errno otherwise
979 event_trigger_parse(struct event_command *cmd_ops,
980 struct trace_event_file *file,
981 char *glob, char *cmd, char *param_and_filter)
983 struct event_trigger_data *trigger_data;
984 char *param, *filter;
988 remove = event_trigger_check_remove(glob);
990 ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, false);
995 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, file);
1000 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
1001 kfree(trigger_data);
1006 ret = event_trigger_parse_num(param, trigger_data);
1010 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
1014 /* Up the trigger_data count to make sure reg doesn't free it on failure */
1015 event_trigger_init(trigger_data);
1017 ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
1021 /* Down the counter of trigger_data or free it if not used anymore */
1022 event_trigger_free(trigger_data);
1027 event_trigger_reset_filter(cmd_ops, trigger_data);
1028 kfree(trigger_data);
1033 * set_trigger_filter - Generic event_command @set_filter implementation
1034 * @filter_str: The filter string for the trigger, NULL to remove filter
1035 * @trigger_data: Trigger-specific data
1036 * @file: The trace_event_file associated with the event
1038 * Common implementation for event command filter parsing and filter
1041 * Usually used directly as the @set_filter method in event command
1044 * Also used to remove a filter (if filter_str = NULL).
1046 * Return: 0 on success, errno otherwise
1048 int set_trigger_filter(char *filter_str,
1049 struct event_trigger_data *trigger_data,
1050 struct trace_event_file *file)
1052 struct event_trigger_data *data = trigger_data;
1053 struct event_filter *filter = NULL, *tmp;
1057 if (!filter_str) /* clear the current filter */
1060 s = strsep(&filter_str, " \t");
1062 if (!strlen(s) || strcmp(s, "if") != 0)
1068 /* The filter is for the 'trigger' event, not the triggered event */
1069 ret = create_event_filter(file->tr, file->event_call,
1070 filter_str, false, &filter);
1072 * If create_event_filter() fails, filter still needs to be freed.
1073 * Which the calling code will do with data->filter.
1076 tmp = rcu_access_pointer(data->filter);
1078 rcu_assign_pointer(data->filter, filter);
1081 /* Make sure the call is done with the filter */
1082 tracepoint_synchronize_unregister();
1083 free_event_filter(tmp);
1086 kfree(data->filter_str);
1087 data->filter_str = NULL;
1090 data->filter_str = kstrdup(filter_str, GFP_KERNEL);
1091 if (!data->filter_str) {
1092 free_event_filter(rcu_access_pointer(data->filter));
1093 data->filter = NULL;
1101 static LIST_HEAD(named_triggers);
1104 * find_named_trigger - Find the common named trigger associated with @name
1105 * @name: The name of the set of named triggers to find the common data for
1107 * Named triggers are sets of triggers that share a common set of
1108 * trigger data. The first named trigger registered with a given name
1109 * owns the common trigger data that the others subsequently
1110 * registered with the same name will reference. This function
1111 * returns the common trigger data associated with that first
1112 * registered instance.
1114 * Return: the common trigger data for the given named trigger on
1115 * success, NULL otherwise.
1117 struct event_trigger_data *find_named_trigger(const char *name)
1119 struct event_trigger_data *data;
1124 list_for_each_entry(data, &named_triggers, named_list) {
1125 if (data->named_data)
1127 if (strcmp(data->name, name) == 0)
1135 * is_named_trigger - determine if a given trigger is a named trigger
1136 * @test: The trigger data to test
1138 * Return: true if 'test' is a named trigger, false otherwise.
1140 bool is_named_trigger(struct event_trigger_data *test)
1142 struct event_trigger_data *data;
1144 list_for_each_entry(data, &named_triggers, named_list) {
1153 * save_named_trigger - save the trigger in the named trigger list
1154 * @name: The name of the named trigger set
1155 * @data: The trigger data to save
1157 * Return: 0 if successful, negative error otherwise.
1159 int save_named_trigger(const char *name, struct event_trigger_data *data)
1161 data->name = kstrdup(name, GFP_KERNEL);
1165 list_add(&data->named_list, &named_triggers);
1171 * del_named_trigger - delete a trigger from the named trigger list
1172 * @data: The trigger data to delete
1174 void del_named_trigger(struct event_trigger_data *data)
1179 list_del(&data->named_list);
1182 static void __pause_named_trigger(struct event_trigger_data *data, bool pause)
1184 struct event_trigger_data *test;
1186 list_for_each_entry(test, &named_triggers, named_list) {
1187 if (strcmp(test->name, data->name) == 0) {
1189 test->paused_tmp = test->paused;
1190 test->paused = true;
1192 test->paused = test->paused_tmp;
1199 * pause_named_trigger - Pause all named triggers with the same name
1200 * @data: The trigger data of a named trigger to pause
1202 * Pauses a named trigger along with all other triggers having the
1203 * same name. Because named triggers share a common set of data,
1204 * pausing only one is meaningless, so pausing one named trigger needs
1205 * to pause all triggers with the same name.
1207 void pause_named_trigger(struct event_trigger_data *data)
1209 __pause_named_trigger(data, true);
1213 * unpause_named_trigger - Un-pause all named triggers with the same name
1214 * @data: The trigger data of a named trigger to unpause
1216 * Un-pauses a named trigger along with all other triggers having the
1217 * same name. Because named triggers share a common set of data,
1218 * unpausing only one is meaningless, so unpausing one named trigger
1219 * needs to unpause all triggers with the same name.
1221 void unpause_named_trigger(struct event_trigger_data *data)
1223 __pause_named_trigger(data, false);
1227 * set_named_trigger_data - Associate common named trigger data
1228 * @data: The trigger data to associate
1229 * @named_data: The common named trigger to be associated
1231 * Named triggers are sets of triggers that share a common set of
1232 * trigger data. The first named trigger registered with a given name
1233 * owns the common trigger data that the others subsequently
1234 * registered with the same name will reference. This function
1235 * associates the common trigger data from the first trigger with the
1238 void set_named_trigger_data(struct event_trigger_data *data,
1239 struct event_trigger_data *named_data)
1241 data->named_data = named_data;
1244 struct event_trigger_data *
1245 get_named_trigger_data(struct event_trigger_data *data)
1247 return data->named_data;
1251 traceon_trigger(struct event_trigger_data *data,
1252 struct trace_buffer *buffer, void *rec,
1253 struct ring_buffer_event *event)
1255 struct trace_event_file *file = data->private_data;
1258 if (tracer_tracing_is_on(file->tr))
1261 tracer_tracing_on(file->tr);
1265 if (tracing_is_on())
1272 traceon_count_trigger(struct event_trigger_data *data,
1273 struct trace_buffer *buffer, void *rec,
1274 struct ring_buffer_event *event)
1276 struct trace_event_file *file = data->private_data;
1279 if (tracer_tracing_is_on(file->tr))
1282 if (tracing_is_on())
1289 if (data->count != -1)
1293 tracer_tracing_on(file->tr);
1299 traceoff_trigger(struct event_trigger_data *data,
1300 struct trace_buffer *buffer, void *rec,
1301 struct ring_buffer_event *event)
1303 struct trace_event_file *file = data->private_data;
1306 if (!tracer_tracing_is_on(file->tr))
1309 tracer_tracing_off(file->tr);
1313 if (!tracing_is_on())
1320 traceoff_count_trigger(struct event_trigger_data *data,
1321 struct trace_buffer *buffer, void *rec,
1322 struct ring_buffer_event *event)
1324 struct trace_event_file *file = data->private_data;
1327 if (!tracer_tracing_is_on(file->tr))
1330 if (!tracing_is_on())
1337 if (data->count != -1)
1341 tracer_tracing_off(file->tr);
1347 traceon_trigger_print(struct seq_file *m, struct event_trigger_data *data)
1349 return event_trigger_print("traceon", m, (void *)data->count,
1354 traceoff_trigger_print(struct seq_file *m, struct event_trigger_data *data)
1356 return event_trigger_print("traceoff", m, (void *)data->count,
1360 static struct event_trigger_ops traceon_trigger_ops = {
1361 .trigger = traceon_trigger,
1362 .print = traceon_trigger_print,
1363 .init = event_trigger_init,
1364 .free = event_trigger_free,
1367 static struct event_trigger_ops traceon_count_trigger_ops = {
1368 .trigger = traceon_count_trigger,
1369 .print = traceon_trigger_print,
1370 .init = event_trigger_init,
1371 .free = event_trigger_free,
1374 static struct event_trigger_ops traceoff_trigger_ops = {
1375 .trigger = traceoff_trigger,
1376 .print = traceoff_trigger_print,
1377 .init = event_trigger_init,
1378 .free = event_trigger_free,
1381 static struct event_trigger_ops traceoff_count_trigger_ops = {
1382 .trigger = traceoff_count_trigger,
1383 .print = traceoff_trigger_print,
1384 .init = event_trigger_init,
1385 .free = event_trigger_free,
1388 static struct event_trigger_ops *
1389 onoff_get_trigger_ops(char *cmd, char *param)
1391 struct event_trigger_ops *ops;
1393 /* we register both traceon and traceoff to this callback */
1394 if (strcmp(cmd, "traceon") == 0)
1395 ops = param ? &traceon_count_trigger_ops :
1396 &traceon_trigger_ops;
1398 ops = param ? &traceoff_count_trigger_ops :
1399 &traceoff_trigger_ops;
1404 static struct event_command trigger_traceon_cmd = {
1406 .trigger_type = ETT_TRACE_ONOFF,
1407 .parse = event_trigger_parse,
1408 .reg = register_trigger,
1409 .unreg = unregister_trigger,
1410 .get_trigger_ops = onoff_get_trigger_ops,
1411 .set_filter = set_trigger_filter,
1414 static struct event_command trigger_traceoff_cmd = {
1416 .trigger_type = ETT_TRACE_ONOFF,
1417 .flags = EVENT_CMD_FL_POST_TRIGGER,
1418 .parse = event_trigger_parse,
1419 .reg = register_trigger,
1420 .unreg = unregister_trigger,
1421 .get_trigger_ops = onoff_get_trigger_ops,
1422 .set_filter = set_trigger_filter,
1425 #ifdef CONFIG_TRACER_SNAPSHOT
1427 snapshot_trigger(struct event_trigger_data *data,
1428 struct trace_buffer *buffer, void *rec,
1429 struct ring_buffer_event *event)
1431 struct trace_event_file *file = data->private_data;
1434 tracing_snapshot_instance(file->tr);
1440 snapshot_count_trigger(struct event_trigger_data *data,
1441 struct trace_buffer *buffer, void *rec,
1442 struct ring_buffer_event *event)
1447 if (data->count != -1)
1450 snapshot_trigger(data, buffer, rec, event);
1454 register_snapshot_trigger(char *glob,
1455 struct event_trigger_data *data,
1456 struct trace_event_file *file)
1458 if (tracing_alloc_snapshot_instance(file->tr) != 0)
1461 return register_trigger(glob, data, file);
1465 snapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data)
1467 return event_trigger_print("snapshot", m, (void *)data->count,
1471 static struct event_trigger_ops snapshot_trigger_ops = {
1472 .trigger = snapshot_trigger,
1473 .print = snapshot_trigger_print,
1474 .init = event_trigger_init,
1475 .free = event_trigger_free,
1478 static struct event_trigger_ops snapshot_count_trigger_ops = {
1479 .trigger = snapshot_count_trigger,
1480 .print = snapshot_trigger_print,
1481 .init = event_trigger_init,
1482 .free = event_trigger_free,
1485 static struct event_trigger_ops *
1486 snapshot_get_trigger_ops(char *cmd, char *param)
1488 return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops;
1491 static struct event_command trigger_snapshot_cmd = {
1493 .trigger_type = ETT_SNAPSHOT,
1494 .parse = event_trigger_parse,
1495 .reg = register_snapshot_trigger,
1496 .unreg = unregister_trigger,
1497 .get_trigger_ops = snapshot_get_trigger_ops,
1498 .set_filter = set_trigger_filter,
1501 static __init int register_trigger_snapshot_cmd(void)
1505 ret = register_event_command(&trigger_snapshot_cmd);
1511 static __init int register_trigger_snapshot_cmd(void) { return 0; }
1512 #endif /* CONFIG_TRACER_SNAPSHOT */
1514 #ifdef CONFIG_STACKTRACE
1515 #ifdef CONFIG_UNWINDER_ORC
1517 * event_triggers_post_call()
1518 * trace_event_raw_event_xxx()
1520 # define STACK_SKIP 2
1524 * stacktrace_trigger()
1525 * event_triggers_post_call()
1526 * trace_event_buffer_commit()
1527 * trace_event_raw_event_xxx()
1529 #define STACK_SKIP 4
1533 stacktrace_trigger(struct event_trigger_data *data,
1534 struct trace_buffer *buffer, void *rec,
1535 struct ring_buffer_event *event)
1537 struct trace_event_file *file = data->private_data;
1540 __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP);
1542 trace_dump_stack(STACK_SKIP);
1546 stacktrace_count_trigger(struct event_trigger_data *data,
1547 struct trace_buffer *buffer, void *rec,
1548 struct ring_buffer_event *event)
1553 if (data->count != -1)
1556 stacktrace_trigger(data, buffer, rec, event);
1560 stacktrace_trigger_print(struct seq_file *m, struct event_trigger_data *data)
1562 return event_trigger_print("stacktrace", m, (void *)data->count,
1566 static struct event_trigger_ops stacktrace_trigger_ops = {
1567 .trigger = stacktrace_trigger,
1568 .print = stacktrace_trigger_print,
1569 .init = event_trigger_init,
1570 .free = event_trigger_free,
1573 static struct event_trigger_ops stacktrace_count_trigger_ops = {
1574 .trigger = stacktrace_count_trigger,
1575 .print = stacktrace_trigger_print,
1576 .init = event_trigger_init,
1577 .free = event_trigger_free,
1580 static struct event_trigger_ops *
1581 stacktrace_get_trigger_ops(char *cmd, char *param)
1583 return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops;
1586 static struct event_command trigger_stacktrace_cmd = {
1587 .name = "stacktrace",
1588 .trigger_type = ETT_STACKTRACE,
1589 .flags = EVENT_CMD_FL_POST_TRIGGER,
1590 .parse = event_trigger_parse,
1591 .reg = register_trigger,
1592 .unreg = unregister_trigger,
1593 .get_trigger_ops = stacktrace_get_trigger_ops,
1594 .set_filter = set_trigger_filter,
1597 static __init int register_trigger_stacktrace_cmd(void)
1601 ret = register_event_command(&trigger_stacktrace_cmd);
1607 static __init int register_trigger_stacktrace_cmd(void) { return 0; }
1608 #endif /* CONFIG_STACKTRACE */
1610 static __init void unregister_trigger_traceon_traceoff_cmds(void)
1612 unregister_event_command(&trigger_traceon_cmd);
1613 unregister_event_command(&trigger_traceoff_cmd);
1617 event_enable_trigger(struct event_trigger_data *data,
1618 struct trace_buffer *buffer, void *rec,
1619 struct ring_buffer_event *event)
1621 struct enable_trigger_data *enable_data = data->private_data;
1623 if (enable_data->enable)
1624 clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags);
1626 set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags);
1630 event_enable_count_trigger(struct event_trigger_data *data,
1631 struct trace_buffer *buffer, void *rec,
1632 struct ring_buffer_event *event)
1634 struct enable_trigger_data *enable_data = data->private_data;
1639 /* Skip if the event is in a state we want to switch to */
1640 if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED))
1643 if (data->count != -1)
1646 event_enable_trigger(data, buffer, rec, event);
1649 int event_enable_trigger_print(struct seq_file *m,
1650 struct event_trigger_data *data)
1652 struct enable_trigger_data *enable_data = data->private_data;
1654 seq_printf(m, "%s:%s:%s",
1656 (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) :
1657 (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR),
1658 enable_data->file->event_call->class->system,
1659 trace_event_name(enable_data->file->event_call));
1661 if (data->count == -1)
1662 seq_puts(m, ":unlimited");
1664 seq_printf(m, ":count=%ld", data->count);
1666 if (data->filter_str)
1667 seq_printf(m, " if %s\n", data->filter_str);
1674 void event_enable_trigger_free(struct event_trigger_data *data)
1676 struct enable_trigger_data *enable_data = data->private_data;
1678 if (WARN_ON_ONCE(data->ref <= 0))
1683 /* Remove the SOFT_MODE flag */
1684 trace_event_enable_disable(enable_data->file, 0, 1);
1685 trace_event_put_ref(enable_data->file->event_call);
1686 trigger_data_free(data);
1691 static struct event_trigger_ops event_enable_trigger_ops = {
1692 .trigger = event_enable_trigger,
1693 .print = event_enable_trigger_print,
1694 .init = event_trigger_init,
1695 .free = event_enable_trigger_free,
1698 static struct event_trigger_ops event_enable_count_trigger_ops = {
1699 .trigger = event_enable_count_trigger,
1700 .print = event_enable_trigger_print,
1701 .init = event_trigger_init,
1702 .free = event_enable_trigger_free,
1705 static struct event_trigger_ops event_disable_trigger_ops = {
1706 .trigger = event_enable_trigger,
1707 .print = event_enable_trigger_print,
1708 .init = event_trigger_init,
1709 .free = event_enable_trigger_free,
1712 static struct event_trigger_ops event_disable_count_trigger_ops = {
1713 .trigger = event_enable_count_trigger,
1714 .print = event_enable_trigger_print,
1715 .init = event_trigger_init,
1716 .free = event_enable_trigger_free,
1719 int event_enable_trigger_parse(struct event_command *cmd_ops,
1720 struct trace_event_file *file,
1721 char *glob, char *cmd, char *param_and_filter)
1723 struct trace_event_file *event_enable_file;
1724 struct enable_trigger_data *enable_data;
1725 struct event_trigger_data *trigger_data;
1726 struct trace_array *tr = file->tr;
1727 char *param, *filter;
1728 bool enable, remove;
1734 remove = event_trigger_check_remove(glob);
1736 if (event_trigger_empty_param(param_and_filter))
1739 ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, true);
1743 system = strsep(¶m, ":");
1747 event = strsep(¶m, ":");
1750 event_enable_file = find_event_file(tr, system, event);
1751 if (!event_enable_file)
1754 #ifdef CONFIG_HIST_TRIGGERS
1755 hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) ||
1756 (strcmp(cmd, DISABLE_HIST_STR) == 0));
1758 enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) ||
1759 (strcmp(cmd, ENABLE_HIST_STR) == 0));
1761 enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
1765 enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL);
1769 enable_data->hist = hist;
1770 enable_data->enable = enable;
1771 enable_data->file = event_enable_file;
1773 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, enable_data);
1774 if (!trigger_data) {
1780 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
1781 kfree(trigger_data);
1787 /* Up the trigger_data count to make sure nothing frees it on failure */
1788 event_trigger_init(trigger_data);
1790 ret = event_trigger_parse_num(param, trigger_data);
1794 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
1798 /* Don't let event modules unload while probe registered */
1799 ret = trace_event_try_get_ref(event_enable_file->event_call);
1805 ret = trace_event_enable_disable(event_enable_file, 1, 1);
1809 ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
1813 event_trigger_free(trigger_data);
1817 trace_event_enable_disable(event_enable_file, 0, 1);
1819 trace_event_put_ref(event_enable_file->event_call);
1821 event_trigger_reset_filter(cmd_ops, trigger_data);
1822 event_trigger_free(trigger_data);
1828 int event_enable_register_trigger(char *glob,
1829 struct event_trigger_data *data,
1830 struct trace_event_file *file)
1832 struct enable_trigger_data *enable_data = data->private_data;
1833 struct enable_trigger_data *test_enable_data;
1834 struct event_trigger_data *test;
1837 lockdep_assert_held(&event_mutex);
1839 list_for_each_entry(test, &file->triggers, list) {
1840 test_enable_data = test->private_data;
1841 if (test_enable_data &&
1842 (test->cmd_ops->trigger_type ==
1843 data->cmd_ops->trigger_type) &&
1844 (test_enable_data->file == enable_data->file)) {
1850 if (data->ops->init) {
1851 ret = data->ops->init(data);
1856 list_add_rcu(&data->list, &file->triggers);
1858 update_cond_flag(file);
1859 ret = trace_event_trigger_enable_disable(file, 1);
1861 list_del_rcu(&data->list);
1862 update_cond_flag(file);
1868 void event_enable_unregister_trigger(char *glob,
1869 struct event_trigger_data *test,
1870 struct trace_event_file *file)
1872 struct enable_trigger_data *test_enable_data = test->private_data;
1873 struct event_trigger_data *data = NULL, *iter;
1874 struct enable_trigger_data *enable_data;
1876 lockdep_assert_held(&event_mutex);
1878 list_for_each_entry(iter, &file->triggers, list) {
1879 enable_data = iter->private_data;
1881 (iter->cmd_ops->trigger_type ==
1882 test->cmd_ops->trigger_type) &&
1883 (enable_data->file == test_enable_data->file)) {
1885 list_del_rcu(&data->list);
1886 trace_event_trigger_enable_disable(file, 0);
1887 update_cond_flag(file);
1892 if (data && data->ops->free)
1893 data->ops->free(data);
1896 static struct event_trigger_ops *
1897 event_enable_get_trigger_ops(char *cmd, char *param)
1899 struct event_trigger_ops *ops;
1902 #ifdef CONFIG_HIST_TRIGGERS
1903 enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) ||
1904 (strcmp(cmd, ENABLE_HIST_STR) == 0));
1906 enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
1909 ops = param ? &event_enable_count_trigger_ops :
1910 &event_enable_trigger_ops;
1912 ops = param ? &event_disable_count_trigger_ops :
1913 &event_disable_trigger_ops;
1918 static struct event_command trigger_enable_cmd = {
1919 .name = ENABLE_EVENT_STR,
1920 .trigger_type = ETT_EVENT_ENABLE,
1921 .parse = event_enable_trigger_parse,
1922 .reg = event_enable_register_trigger,
1923 .unreg = event_enable_unregister_trigger,
1924 .get_trigger_ops = event_enable_get_trigger_ops,
1925 .set_filter = set_trigger_filter,
1928 static struct event_command trigger_disable_cmd = {
1929 .name = DISABLE_EVENT_STR,
1930 .trigger_type = ETT_EVENT_ENABLE,
1931 .parse = event_enable_trigger_parse,
1932 .reg = event_enable_register_trigger,
1933 .unreg = event_enable_unregister_trigger,
1934 .get_trigger_ops = event_enable_get_trigger_ops,
1935 .set_filter = set_trigger_filter,
1938 static __init void unregister_trigger_enable_disable_cmds(void)
1940 unregister_event_command(&trigger_enable_cmd);
1941 unregister_event_command(&trigger_disable_cmd);
1944 static __init int register_trigger_enable_disable_cmds(void)
1948 ret = register_event_command(&trigger_enable_cmd);
1949 if (WARN_ON(ret < 0))
1951 ret = register_event_command(&trigger_disable_cmd);
1952 if (WARN_ON(ret < 0))
1953 unregister_trigger_enable_disable_cmds();
1958 static __init int register_trigger_traceon_traceoff_cmds(void)
1962 ret = register_event_command(&trigger_traceon_cmd);
1963 if (WARN_ON(ret < 0))
1965 ret = register_event_command(&trigger_traceoff_cmd);
1966 if (WARN_ON(ret < 0))
1967 unregister_trigger_traceon_traceoff_cmds();
1972 __init int register_trigger_cmds(void)
1974 register_trigger_traceon_traceoff_cmds();
1975 register_trigger_snapshot_cmd();
1976 register_trigger_stacktrace_cmd();
1977 register_trigger_enable_disable_cmds();
1978 register_trigger_hist_enable_disable_cmds();
1979 register_trigger_hist_cmd();