/*
* trace_events_trigger - trace event triggers
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com>
*/
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include "trace.h"
static LIST_HEAD(trigger_commands);
static DEFINE_MUTEX(trigger_cmd_mutex);
static void
trigger_data_free(struct event_trigger_data *data)
{
synchronize_sched(); /* make sure current triggers exit before free */
kfree(data);
}
/**
* event_triggers_call - Call triggers associated with a trace event
* @file: The ftrace_event_file associated with the event
*
* For each trigger associated with an event, invoke the trigger
* function registered with the associated trigger command.
*
* 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.
*/
void event_triggers_call(struct ftrace_event_file *file)
{
struct event_trigger_data *data;
if (list_empty(&file->triggers))
return;
list_for_each_entry_rcu(data, &file->triggers, list)
data->ops->func(data);
}
EXPORT_SYMBOL_GPL(event_triggers_call);
static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
{
struct ftrace_event_file *event_file = event_file_data(m->private);
return seq_list_next(t, &event_file->triggers, pos);
}
static void *trigger_start(struct seq_file *m, loff_t *pos)
{
struct ftrace_event_file *event_file;
/* ->stop() is called even if ->start() fails */
mutex_lock(&event_mutex);
event_file = event_file_data(m->private);
if (unlikely(!event_file))
return ERR_PTR(-ENODEV);
return seq_list_start(&event_file->triggers, *pos);
}
static void trigger_stop(struct seq_file *m, void *t)
{
mutex_unlock(&event_mutex);
}
static int trigger_show(struct seq_file *m, void *v)
{
struct event_trigger_data *data;
data = list_entry(v, struct event_trigger_data, list);
data->ops->print(m, data->ops, data);
return 0;
}
static const struct seq_operations event_triggers_seq_ops = {
.start = trigger_start,
.next = trigger_next,
.stop = trigger_stop,
.show = trigger_show,
};
static int event_trigger_regex_open(struct inode *inode, struct file *file)
{
int ret = 0;
mutex_lock(&