Add priority to defaultOn plugins list

pkg/kubeapiserver/options/plugins.go

@@ -57,6 +57,8 @@ import (
 	"k8s.io/apiserver/pkg/admission/plugin/namespace/lifecycle"
 	mutatingwebhook "k8s.io/apiserver/pkg/admission/plugin/webhook/mutating"
 	validatingwebhook "k8s.io/apiserver/pkg/admission/plugin/webhook/validating"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 // AllOrderedPlugins is the list of all the plugins in order.
@@ -139,5 +141,9 @@ func DefaultOffAdmissionPlugins() sets.String {
 		resourcequota.PluginName,            //ResourceQuota
 	)
 
+	if utilfeature.DefaultFeatureGate.Enabled(features.PodPriority) {
+		defaultOnPlugins.Insert(podpriority.PluginName) //PodPriority
+	}
+
 	return sets.NewString(AllOrderedPlugins...).Difference(defaultOnPlugins)
 }