Add PodRemovedFromVolume

To know when a volume has been fully unmounted (incl. uncertain mounts).

pkg/kubelet/kubelet_volumes.go

@@ -71,7 +71,7 @@ func (kl *Kubelet) ListBlockVolumesForPod(podUID types.UID) (map[string]volume.B
 }
 
 // podVolumesExist checks with the volume manager and returns true any of the
-// pods for the specified volume are mounted.
+// pods for the specified volume are mounted or are uncertain.
 func (kl *Kubelet) podVolumesExist(podUID types.UID) bool {
 	if mountedVolumes :=
 		kl.volumeManager.GetPossiblyMountedVolumesForPod(

pkg/kubelet/volumemanager/cache/actual_state_of_world.go

@@ -110,6 +110,14 @@ type ActualStateOfWorld interface {
 	// volumes that do not need to update contents should not fail.
 	PodExistsInVolume(podName volumetypes.UniquePodName, volumeName v1.UniqueVolumeName) (bool, string, error)
 
+	// PodRemovedFromVolume returns true if the given pod does not exist in the list of
+	// mountedPods for the given volume in the cache, indicating that the pod has
+	// fully unmounted it or it was never mounted the volume.
+	// If the volume is fully mounted or is in uncertain mount state for the pod, it is
+	// considered that the pod still exists in volume manager's actual state of the world
+	// and false is returned.
+	PodRemovedFromVolume(podName volumetypes.UniquePodName, volumeName v1.UniqueVolumeName) bool
+
 	// VolumeExistsWithSpecName returns true if the given volume specified with the
 	// volume spec name (a.k.a., InnerVolumeSpecName) exists in the list of
 	// volumes that should be attached to this node.
@@ -686,6 +694,31 @@ func (asw *actualStateOfWorld) PodExistsInVolume(
 	return podExists, volumeObj.devicePath, nil
 }
 
+func (asw *actualStateOfWorld) PodRemovedFromVolume(
+	podName volumetypes.UniquePodName,
+	volumeName v1.UniqueVolumeName) bool {
+	asw.RLock()
+	defer asw.RUnlock()
+
+	volumeObj, volumeExists := asw.attachedVolumes[volumeName]
+	if !volumeExists {
+		return true
+	}
+
+	podObj, podExists := volumeObj.mountedPods[podName]
+	if podExists {
+		// if volume mount was uncertain we should keep trying to unmount the volume
+		if podObj.volumeMountStateForPod == operationexecutor.VolumeMountUncertain {
+			return false
+		}
+		if podObj.volumeMountStateForPod == operationexecutor.VolumeMounted {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (asw *actualStateOfWorld) VolumeExistsWithSpecName(podName volumetypes.UniquePodName, volumeSpecName string) bool {
 	asw.RLock()
 	defer asw.RUnlock()

pkg/kubelet/volumemanager/cache/actual_state_of_world_test.go

@@ -671,6 +671,10 @@ func TestUncertainVolumeMounts(t *testing.T) {
 	if volExists {
 		t.Fatalf("expected volume %s to not exist in asw", generatedVolumeName1)
 	}
+	removed := asw.PodRemovedFromVolume(podName1, generatedVolumeName1)
+	if removed {
+		t.Fatalf("expected volume %s not to be removed in asw", generatedVolumeName1)
+	}
 }
 
 func verifyVolumeExistsInGloballyMountedVolumes(

pkg/kubelet/volumemanager/populator/desired_state_of_world_populator.go

@@ -278,12 +278,12 @@ func (dswp *desiredStateOfWorldPopulator) findAndRemoveDeletedPods() {
 			klog.V(4).InfoS("Pod still has one or more containers in the non-exited state and will not be removed from desired state", "pod", klog.KObj(volumeToMount.Pod))
 			continue
 		}
-		exists, _, _ := dswp.actualStateOfWorld.PodExistsInVolume(volumeToMount.PodName, volumeToMount.VolumeName)
 		var volumeToMountSpecName string
 		if volumeToMount.VolumeSpec != nil {
 			volumeToMountSpecName = volumeToMount.VolumeSpec.Name()
 		}
-		if !exists && podExists {
+		removed := dswp.actualStateOfWorld.PodRemovedFromVolume(volumeToMount.PodName, volumeToMount.VolumeName)
+		if removed && podExists {
 			klog.V(4).InfoS("Actual state does not yet have volume mount information and pod still exists in pod manager, skip removing volume from desired state", "pod", klog.KObj(volumeToMount.Pod), "podUID", volumeToMount.Pod.UID, "volumeName", volumeToMountSpecName)
 			continue
 		}