// SPDX-License-Identifier: GPL-2.0
/*
* trace_events_trigger - trace event triggers
*
* Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com>
*/
#include <linux/security.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/rculist.h>
#include "trace.h"
static LIST_HEAD(trigger_commands);
static DEFINE_MUTEX(trigger_cmd_mutex);
void trigger_data_free(struct event_trigger_data *data)
{
if (data->cmd_ops->set_filter)
data->cmd_ops->set_filter(NULL, data, NULL);
/* make sure current triggers exit before free */
tracepoint_synchronize_unregister();
kfree(data);
}
/**
* event_triggers_call - Call triggers associated with a trace event
* @file: The trace_event_file associated with the event
* @rec: The trace entry for the event, NULL for unconditional invocation
*
* For each trigger associated with an event, invoke the trigger
* function registered with the associated trigger command. If rec is
* non-NULL, it means that the trigger requires further processing and
* shouldn't be unconditionally invoked. If rec is non-NULL and the
* trigger has a filter associated with it, rec will checked against
* the filter and if the record matches the trigger will be invoked.
* If the trigger is a 'post_trigger', meaning it shouldn't be invoked
* in any case until the current event is written, the trigger
* function isn't invoked but the bit associated with the deferred
* trigger is set in the return value.
*
* Returns an enum event_trigger_type value containing a set bit for
* any trigger that should be deferred, ETT_NONE if nothing to defer.
*
* Called from tracepoint handlers (with rcu_read_lock_sched() held).
*
* Return: an enum event_trigger_type value containing a set bit for
* any trigger that should be deferred, ETT_NONE if nothing to defer.
*/
enum event_trigger_type
event_triggers_call(struct trace_event_file *file, void *rec,
struct ring_buffer_event *event)
{
struct event_trigger_data *data;
enum event_trigger_type tt = ETT_NONE;
struct event_filter *filter;
if (list_empty(&file->triggers))
return tt;
list_for_each_entry_rcu(data, &file->triggers, list) {
if (data->paused)
continue;
if (!rec) {
data->ops->func(data, rec, event);
continue;
}
filter = rcu_dereference_sched(data->filter);
if (filter && !filter_match_preds(filter, rec))
continue;
if (event_command_post_trigger(data->cmd_ops)) {
tt |= data->cmd_ops->trigger_type;
continue;
}
data->ops->func(data, rec, event);
}
return tt;
}
EXPORT_SYMBOL_GPL(event_triggers_call);
/**
* event_triggers_post_call - Call 'post_triggers' for a trace event
* @file: The trace_event_file associated with the event
* @tt: enum event_trigger_type containing a set bit for each trigger to invoke
*
* For each trigger associated with an event, invoke the trigger
* function registered with the associated trigger command, if the
* corresponding bit is set in the tt enum passed into this function.
* See @event_triggers_call for details on how those bits are set.
*
* Called from tracepoint handlers (with rcu_read_lock_sched() held).
*/
void
event_triggers_p
| 