perf_events: Undo copy/paste damage

We had two almost identical functions, avoid the duplication.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091123103819.537537928@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/perf_event.c

@@ -1704,16 +1704,10 @@ static void free_event(struct perf_event *event)
 	call_rcu(&event->rcu_head, free_event_rcu);
 }
 
-/*
- * Called when the last reference to the file is gone.
- */
-static int perf_release(struct inode *inode, struct file *file)
+int perf_event_release_kernel(struct perf_event *event)
 {
-	struct perf_event *event = file->private_data;
 	struct perf_event_context *ctx = event->ctx;
 
-	file->private_data = NULL;
-
 	WARN_ON_ONCE(ctx->parent_ctx);
 	mutex_lock(&ctx->mutex);
 	perf_event_remove_from_context(event);
@@ -1728,26 +1722,19 @@ static int perf_release(struct inode *inode, struct file *file)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(perf_event_release_kernel);
 
-int perf_event_release_kernel(struct perf_event *event)
+/*
+ * Called when the last reference to the file is gone.
+ */
+static int perf_release(struct inode *inode, struct file *file)
 {
-	struct perf_event_context *ctx = event->ctx;
-
-	WARN_ON_ONCE(ctx->parent_ctx);
-	mutex_lock(&ctx->mutex);
-	perf_event_remove_from_context(event);
-	mutex_unlock(&ctx->mutex);
-
-	mutex_lock(&event->owner->perf_event_mutex);
-	list_del_init(&event->owner_entry);
-	mutex_unlock(&event->owner->perf_event_mutex);
-	put_task_struct(event->owner);
+	struct perf_event *event = file->private_data;
 
-	free_event(event);
+	file->private_data = NULL;
 
-	return 0;
+	return perf_event_release_kernel(event);
 }
-EXPORT_SYMBOL_GPL(perf_event_release_kernel);
 
 static int perf_event_read_size(struct perf_event *event)
 {