[PATCH 6/6] tracing/dynevent: Adopt guard() and scoped_guard()

[Masami Hiramatsu (Google)]

From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>

Use guard() or scoped_guard() in dynamic events for critical sections
rather than discrete lock/unlock pairs.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
---
 kernel/trace/trace_dynevent.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index 4376887e0d8a..dbdcaef08f5d 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -63,9 +63,8 @@ int dyn_event_register(struct dyn_event_operations *ops)
 		return -EINVAL;
 
 	INIT_LIST_HEAD(&ops->list);
-	mutex_lock(&dyn_event_ops_mutex);
+	guard(mutex)(&dyn_event_ops_mutex);
 	list_add_tail(&ops->list, &dyn_event_ops_list);
-	mutex_unlock(&dyn_event_ops_mutex);
 	return 0;
 }
 
@@ -106,7 +105,7 @@ int dyn_event_release(const char *raw_command, struct dyn_event_operations *type
 		goto out;
 	}
 
-	mutex_lock(&event_mutex);
+	guard(mutex)(&event_mutex);
 	for_each_dyn_event_safe(pos, n) {
 		if (type && type != pos->ops)
 			continue;
@@ -119,7 +118,6 @@ int dyn_event_release(const char *raw_command, struct dyn_event_operations *type
 			break;
 	}
 	tracing_reset_all_online_cpus();
-	mutex_unlock(&event_mutex);
 out:
 	argv_free(argv);
 	return ret;
@@ -133,13 +131,12 @@ static int create_dyn_event(const char *raw_command)
 	if (raw_command[0] == '-' || raw_command[0] == '!')
 		return dyn_event_release(raw_command, NULL);
 
-	mutex_lock(&dyn_event_ops_mutex);
+	guard(mutex)(&dyn_event_ops_mutex);
 	list_for_each_entry(ops, &dyn_event_ops_list, list) {
 		ret = ops->create(raw_command);
 		if (!ret || ret != -ECANCELED)
 			break;
 	}
-	mutex_unlock(&dyn_event_ops_mutex);
 	if (ret == -ECANCELED)
 		ret = -EINVAL;
 
@@ -198,7 +195,7 @@ int dyn_events_release_all(struct dyn_event_operations *type)
 	struct dyn_event *ev, *tmp;
 	int ret = 0;
 
-	mutex_lock(&event_mutex);
+	guard(mutex)(&event_mutex);
 	for_each_dyn_event(ev) {
 		if (type && ev->ops != type)
 			continue;
@@ -216,7 +213,6 @@ int dyn_events_release_all(struct dyn_event_operations *type)
 	}
 out:
 	tracing_reset_all_online_cpus();
-	mutex_unlock(&event_mutex);
 
 	return ret;
 }