diff --git a/vendor/go.etcd.io/etcd/clientv3/concurrency/doc.go b/vendor/go.etcd.io/etcd/clientv3/concurrency/doc.go
new file mode 100644
index 0000000..dcdbf51
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/clientv3/concurrency/doc.go
@@ -0,0 +1,17 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package concurrency implements concurrency operations on top of
+// etcd such as distributed locks, barriers, and elections.
+package concurrency