cgroups: make unlock sequence in cgroup_get_sb consistent

Make the last unlock sequence consistent with previous unlock sequeue.

Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index cd83d99..f5281aa 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1155,8 +1155,8 @@
 		BUG_ON(root->number_of_cgroups != 1);
 
 		cgroup_populate_dir(root_cgrp);
-		mutex_unlock(&inode->i_mutex);
 		mutex_unlock(&cgroup_mutex);
+		mutex_unlock(&inode->i_mutex);
 	}
 
 	simple_set_mnt(mnt, sb);