volumebinding: scheduler queueing hints - PersistentVolumeClaim

pkg/scheduler/framework/plugins/volumebinding/volume_binding.go

@@ -99,9 +99,11 @@ func (pl *VolumeBinding) EventsToRegister() []framework.ClusterEventWithHint {
 		// (e.g., allowedTopologies, volumeBindingMode), and hence may become
 		// schedulable upon StorageClass Add or Update events.
 		{Event: framework.ClusterEvent{Resource: framework.StorageClass, ActionType: framework.Add | framework.Update}},
+
 		// We bind PVCs with PVs, so any changes may make the pods schedulable.
-		{Event: framework.ClusterEvent{Resource: framework.PersistentVolumeClaim, ActionType: framework.Add | framework.Update}},
+		{Event: framework.ClusterEvent{Resource: framework.PersistentVolumeClaim, ActionType: framework.Add | framework.Update}, QueueingHintFn: pl.isSchedulableAfterPersistentVolumeClaimChange},
 		{Event: framework.ClusterEvent{Resource: framework.PersistentVolume, ActionType: framework.Add | framework.Update}},
+
 		// Pods may fail to find available PVs because the node labels do not
 		// match the storage class's allowed topologies or PV's node affinity.
 		// A new or updated node may make pods schedulable.
@@ -115,9 +117,11 @@ func (pl *VolumeBinding) EventsToRegister() []framework.ClusterEventWithHint {
 		// We can remove UpdateNodeTaint when we remove the preCheck feature.
 		// See: https://github.com/kubernetes/kubernetes/issues/110175
 		{Event: framework.ClusterEvent{Resource: framework.Node, ActionType: framework.Add | framework.UpdateNodeLabel | framework.UpdateNodeTaint}},
+
 		// We rely on CSI node to translate in-tree PV to CSI.
 		// TODO: kube-schduler will unregister the CSINode events once all the volume plugins has completed their CSI migration.
 		{Event: framework.ClusterEvent{Resource: framework.CSINode, ActionType: framework.Add | framework.Update}, QueueingHintFn: pl.isSchedulableAfterCSINodeChange},
+
 		// When CSIStorageCapacity is enabled, pods may become schedulable
 		// on CSI driver & storage capacity changes.
 		{Event: framework.ClusterEvent{Resource: framework.CSIDriver, ActionType: framework.Add | framework.Update}},
@@ -151,6 +155,46 @@ func (pl *VolumeBinding) isSchedulableAfterCSINodeChange(logger klog.Logger, pod
 	return framework.QueueSkip, nil
 }
 
+func (pl *VolumeBinding) isSchedulableAfterPersistentVolumeClaimChange(logger klog.Logger, pod *v1.Pod, oldObj, newObj interface{}) (framework.QueueingHint, error) {
+	_, newPVC, err := util.As[*v1.PersistentVolumeClaim](oldObj, newObj)
+	if err != nil {
+		return framework.Queue, err
+	}
+
+	logger = klog.LoggerWithValues(
+		logger,
+		"Pod", klog.KObj(pod),
+		"PersistentVolumeClaim", klog.KObj(newPVC),
+	)
+
+	if pod.Namespace != newPVC.Namespace {
+		logger.V(5).Info("PersistentVolumeClaim was created or updated, but it doesn't make this pod schedulable because the PVC belongs to a different namespace")
+		return framework.QueueSkip, nil
+	}
+
+	for _, vol := range pod.Spec.Volumes {
+		var pvcName string
+		switch {
+		case vol.PersistentVolumeClaim != nil:
+			pvcName = vol.PersistentVolumeClaim.ClaimName
+		case vol.Ephemeral != nil:
+			pvcName = ephemeral.VolumeClaimName(pod, &vol)
+		default:
+			continue
+		}
+
+		if pvcName == newPVC.Name {
+			// Return Queue because, in this case,
+			// all PVC creations and almost all PVC updates could make the Pod schedulable.
+			logger.V(5).Info("PersistentVolumeClaim the pod requires was created or updated, potentially making the target Pod schedulable")
+			return framework.Queue, nil
+		}
+	}
+
+	logger.V(5).Info("PersistentVolumeClaim was created or updated, but it doesn't make this pod schedulable")
+	return framework.QueueSkip, nil
+}
+
 // podHasPVCs returns 2 values:
 // - the first one to denote if the given "pod" has any PVC defined.
 // - the second one to return any error if the requested PVC is illegal.

pkg/scheduler/framework/plugins/volumebinding/volume_binding_test.go

@@ -996,3 +996,100 @@ func TestIsSchedulableAfterCSINodeChange(t *testing.T) {
 		})
 	}
 }
+
+func TestIsSchedulableAfterPersistentVolumeClaimChange(t *testing.T) {
+	table := []struct {
+		name    string
+		pod     *v1.Pod
+		oldPVC  interface{}
+		newPVC  interface{}
+		wantErr bool
+		expect  framework.QueueingHint
+	}{
+		{
+			name:    "pod has no pvc or ephemeral volumes",
+			pod:     makePod("pod-a").withEmptyDirVolume().Pod,
+			oldPVC:  makePVC("pvc-b", "sc-a").PersistentVolumeClaim,
+			newPVC:  makePVC("pvc-b", "sc-a").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.QueueSkip,
+		},
+		{
+			name: "pvc with the same name as the one used by the pod in a different namespace is modified",
+			pod: makePod("pod-a").
+				withNamespace("ns-a").
+				withPVCVolume("pvc-a", "").
+				withPVCVolume("pvc-b", "").
+				Pod,
+			oldPVC:  nil,
+			newPVC:  makePVC("pvc-b", "").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.QueueSkip,
+		},
+		{
+			name: "pod has no pvc that is being modified",
+			pod: makePod("pod-a").
+				withPVCVolume("pvc-a", "").
+				withPVCVolume("pvc-c", "").
+				Pod,
+			oldPVC:  makePVC("pvc-b", "").PersistentVolumeClaim,
+			newPVC:  makePVC("pvc-b", "").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.QueueSkip,
+		},
+		{
+			name: "pod has no generic ephemeral volume that is being modified",
+			pod: makePod("pod-a").
+				withGenericEphemeralVolume("ephemeral-a").
+				withGenericEphemeralVolume("ephemeral-c").
+				Pod,
+			oldPVC:  makePVC("pod-a-ephemeral-b", "").PersistentVolumeClaim,
+			newPVC:  makePVC("pod-a-ephemeral-b", "").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.QueueSkip,
+		},
+		{
+			name: "pod has the pvc that is being modified",
+			pod: makePod("pod-a").
+				withPVCVolume("pvc-a", "").
+				withPVCVolume("pvc-b", "").
+				Pod,
+			oldPVC:  makePVC("pvc-b", "").PersistentVolumeClaim,
+			newPVC:  makePVC("pvc-b", "").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.Queue,
+		},
+		{
+			name: "pod has the generic ephemeral volume that is being modified",
+			pod: makePod("pod-a").
+				withGenericEphemeralVolume("ephemeral-a").
+				withGenericEphemeralVolume("ephemeral-b").
+				Pod,
+			oldPVC:  makePVC("pod-a-ephemeral-b", "").PersistentVolumeClaim,
+			newPVC:  makePVC("pod-a-ephemeral-b", "").PersistentVolumeClaim,
+			wantErr: false,
+			expect:  framework.Queue,
+		},
+		{
+			name:    "type conversion error",
+			oldPVC:  new(struct{}),
+			newPVC:  new(struct{}),
+			wantErr: true,
+			expect:  framework.Queue,
+		},
+	}
+
+	for _, item := range table {
+		t.Run(item.name, func(t *testing.T) {
+			pl := &VolumeBinding{}
+			logger, _ := ktesting.NewTestContext(t)
+			qhint, err := pl.isSchedulableAfterPersistentVolumeClaimChange(logger, item.pod, item.oldPVC, item.newPVC)
+			if (err != nil) != item.wantErr {
+				t.Errorf("isSchedulableAfterPersistentVolumeClaimChange failed - got: %q", err)
+			}
+			if qhint != item.expect {
+				t.Errorf("QHint does not match: %v, want: %v", qhint, item.expect)
+			}
+		})
+	}
+}