Clear cache instead of saving nils if no claims to bind or provision

pkg/controller/volume/persistentvolume/scheduler_binder.go

@@ -182,6 +182,11 @@ func (b *volumeBinder) FindPodVolumes(pod *v1.Pod, node *v1.Node) (unboundVolume
 	)
 	defer func() {
 		// We recreate bindings for each new schedule loop.
+		if len(matchedClaims) == 0 && len(provisionedClaims) == 0 {
+			// Clear cache if no claims to bind or provision for this node.
+			b.podBindingCache.ClearBindings(pod, node.Name)
+			return
+		}
 		// Although we do not distinguish nil from empty in this function, for
 		// easier testing, we normalize empty to nil.
 		if len(matchedClaims) == 0 {

pkg/controller/volume/persistentvolume/scheduler_binder_cache.go

@@ -30,6 +30,9 @@ type PodBindingCache interface {
 	// pod and node.
 	UpdateBindings(pod *v1.Pod, node string, bindings []*bindingInfo, provisionings []*v1.PersistentVolumeClaim)
 
+	// ClearBindings will clear the cached bindings for the given pod and node.
+	ClearBindings(pod *v1.Pod, node string)
+
 	// GetBindings will return the cached bindings for the given pod and node.
 	// A nil return value means that the entry was not found. An empty slice
 	// means that no binding operations are needed.
@@ -148,3 +151,15 @@ func (c *podBindingCache) GetProvisionedPVCs(pod *v1.Pod, node string) []*v1.Per
 	}
 	return decision.provisionings
 }
+
+func (c *podBindingCache) ClearBindings(pod *v1.Pod, node string) {
+	c.rwMutex.Lock()
+	defer c.rwMutex.Unlock()
+
+	podName := getPodName(pod)
+	decisions, ok := c.bindingDecisions[podName]
+	if !ok {
+		return
+	}
+	delete(decisions, node)
+}