node labels and taints do not change, node events are ignored in daemonset controller

Signed-off-by: xigang <wangxigang2014@gmail.com>

pkg/controller/daemon/daemon_controller.go

@@ -24,8 +24,6 @@ import (
 	"sync"
 	"time"
 
-	"k8s.io/klog/v2"
-
 	apps "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
@@ -49,6 +47,7 @@ import (
 	"k8s.io/client-go/util/workqueue"
 	v1helper "k8s.io/component-helpers/scheduling/corev1"
 	"k8s.io/component-helpers/scheduling/corev1/nodeaffinity"
+	"k8s.io/klog/v2"
 	podutil "k8s.io/kubernetes/pkg/api/v1/pod"
 	"k8s.io/kubernetes/pkg/controller"
 	"k8s.io/kubernetes/pkg/controller/daemon/util"
@@ -654,42 +653,11 @@ func (dsc *DaemonSetsController) addNode(logger klog.Logger, obj interface{}) {
 	}
 }
 
-// nodeInSameCondition returns true if all effective types ("Status" is true) equals;
-// otherwise, returns false.
-func nodeInSameCondition(old []v1.NodeCondition, cur []v1.NodeCondition) bool {
-	if len(old) == 0 && len(cur) == 0 {
-		return true
-	}
-
-	c1map := map[v1.NodeConditionType]v1.ConditionStatus{}
-	for _, c := range old {
-		if c.Status == v1.ConditionTrue {
-			c1map[c.Type] = c.Status
-		}
-	}
-
-	for _, c := range cur {
-		if c.Status != v1.ConditionTrue {
-			continue
-		}
-
-		if _, found := c1map[c.Type]; !found {
-			return false
-		}
-
-		delete(c1map, c.Type)
-	}
-
-	return len(c1map) == 0
-}
-
+// shouldIgnoreNodeUpdate returns true if Node labels and taints have not changed, otherwise returns false.
+// If other calling functions need to use other properties of Node, shouldIgnoreNodeUpdate needs to be updated.
 func shouldIgnoreNodeUpdate(oldNode, curNode v1.Node) bool {
-	if !nodeInSameCondition(oldNode.Status.Conditions, curNode.Status.Conditions) {
-		return false
-	}
-	oldNode.ResourceVersion = curNode.ResourceVersion
-	oldNode.Status.Conditions = curNode.Status.Conditions
-	return apiequality.Semantic.DeepEqual(oldNode, curNode)
+	return apiequality.Semantic.DeepEqual(oldNode.Labels, curNode.Labels) &&
+		apiequality.Semantic.DeepEqual(oldNode.Spec.Taints, curNode.Spec.Taints)
 }
 
 func (dsc *DaemonSetsController) updateNode(logger klog.Logger, old, cur interface{}) {
@@ -706,6 +674,7 @@ func (dsc *DaemonSetsController) updateNode(logger klog.Logger, old, cur interfa
 	}
 	// TODO: it'd be nice to pass a hint with these enqueues, so that each ds would only examine the added node (unless it has other work to do, too).
 	for _, ds := range dsList {
+		// If NodeShouldRunDaemonPod needs to uses other than Labels and Taints (mutable) properties of node, it needs to update shouldIgnoreNodeUpdate.
 		oldShouldRun, oldShouldContinueRunning := NodeShouldRunDaemonPod(oldNode, ds)
 		currentShouldRun, currentShouldContinueRunning := NodeShouldRunDaemonPod(curNode, ds)
 		if (oldShouldRun != currentShouldRun) || (oldShouldContinueRunning != currentShouldContinueRunning) {

pkg/controller/daemon/daemon_controller_test.go

@@ -3580,3 +3580,43 @@ func TestStoreDaemonSetStatus(t *testing.T) {
 		})
 	}
 }
+
+func TestShouldIgnoreNodeUpdate(t *testing.T) {
+	cases := []struct {
+		name           string
+		newNode        *v1.Node
+		oldNode        *v1.Node
+		expectedResult bool
+	}{
+		{
+			name:           "Nothing changed",
+			oldNode:        newNode("node1", nil),
+			newNode:        newNode("node1", nil),
+			expectedResult: true,
+		},
+		{
+			name:           "Node labels changed",
+			oldNode:        newNode("node1", nil),
+			newNode:        newNode("node1", simpleNodeLabel),
+			expectedResult: false,
+		},
+		{
+			name: "Node taints changed",
+			oldNode: func() *v1.Node {
+				node := newNode("node1", nil)
+				setNodeTaint(node, noScheduleTaints)
+				return node
+			}(),
+			newNode:        newNode("node1", nil),
+			expectedResult: false,
+		},
+	}
+
+	for _, c := range cases {
+		result := shouldIgnoreNodeUpdate(*c.oldNode, *c.newNode)
+
+		if result != c.expectedResult {
+			t.Errorf("[%s] unexpected results: %v", c.name, result)
+		}
+	}
+}