kubelet: Don't attempt to apply the oom score if the container is not running

pkg/kubelet/dockertools/manager.go

@@ -1494,14 +1494,28 @@ func (dm *DockerManager) runContainerInPod(pod *api.Pod, container *api.Containe
 	if err != nil {
 		return kubecontainer.ContainerID{}, fmt.Errorf("InspectContainer: %v", err)
 	}
+
+	if !containerInfo.State.Running {
+		if container.Name == PodInfraContainerName {
+			// If the infra container exited prematurely, return an error to raise
+			// awareness.
+			return id, fmt.Errorf("Infra container %q exited prematruely", id)
+		}
+		// For a user container, simply returns since we cannot apply oom score
+		// anymore.
+		glog.V(4).Info("Container %q already exited", containerInfo.ID)
+		return id, nil
+	}
+
 	// Ensure the PID actually exists, else we'll move ourselves.
+	// TODO: Should we simply log the error (or send an event) and move on? We
+	// don't check the oom score in the next sync and correct it anyway.
 	if containerInfo.State.Pid == 0 {
 		return kubecontainer.ContainerID{}, fmt.Errorf("can't get init PID for container %q", id)
 	}
-
 	// Check if current docker version is higher than 1.10. Otherwise, we have to apply OOMScoreAdj instead of using docker API.
-	err = dm.applyOOMScoreAdjIfNeeded(container, containerInfo)
-	if err != nil {
+	// TODO: Remove this logic after we stop supporting docker version < 1.10.
+	if err := dm.applyOOMScoreAdjIfNeeded(container, containerInfo); err != nil {
 		return kubecontainer.ContainerID{}, err
 	}