Add support for svclb pod PriorityClassName

Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
(cherry picked from commit 37f97b33c9)
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>

pkg/cloudprovider/cloudprovider.go

@@ -28,6 +28,7 @@ import (
 // Config describes externally-configurable cloud provider configuration.
 // This is normally unmarshalled from a JSON config file.
 type Config struct {
+	LBDefaultPriorityClassName string `json:"lbDefaultPriorityClassName"`
 	LBEnabled                  bool   `json:"lbEnabled"`
 	LBImage                    string `json:"lbImage"`
 	LBNamespace                string `json:"lbNamespace"`
@@ -56,6 +57,7 @@ func init() {
 		var err error
 		k := k3s{
 			Config: Config{
+				LBDefaultPriorityClassName: DefaultLBPriorityClassName,
 				LBEnabled:                  true,
 				LBImage:                    DefaultLBImage,
 				LBNamespace:                DefaultLBNS,

pkg/cloudprovider/servicelb.go

@@ -39,12 +39,14 @@ var (
 	daemonsetNodeLabel     = "svccontroller." + version.Program + ".cattle.io/enablelb"
 	daemonsetNodePoolLabel = "svccontroller." + version.Program + ".cattle.io/lbpool"
 	nodeSelectorLabel      = "svccontroller." + version.Program + ".cattle.io/nodeselector"
+	priorityAnnotation     = "svccontroller." + version.Program + ".cattle.io/priorityclassname"
 	controllerName         = ccmapp.DefaultInitFuncConstructors["service"].InitContext.ClientName
 )
 
 const (
 	Ready                      = condition.Cond("Ready")
 	DefaultLBNS                = meta.NamespaceSystem
+	DefaultLBPriorityClassName = "system-node-critical"
 )
 
 var (
@@ -426,6 +428,7 @@ func (k *k3s) deleteDaemonSet(ctx context.Context, svc *core.Service) error {
 func (k *k3s) newDaemonSet(svc *core.Service) (*apps.DaemonSet, error) {
 	name := generateName(svc)
 	oneInt := intstr.FromInt(1)
+	priorityClassName := k.getPriorityClassName(svc)
 	localTraffic := servicehelper.RequestsOnlyLocalTraffic(svc)
 	sourceRangesSet, err := servicehelper.GetLoadBalancerSourceRanges(svc)
 	if err != nil {
@@ -470,6 +473,7 @@ func (k *k3s) newDaemonSet(svc *core.Service) (*apps.DaemonSet, error) {
 					},
 				},
 				Spec: core.PodSpec{
+					PriorityClassName:            priorityClassName,
 					ServiceAccountName:           "svclb",
 					AutomountServiceAccountToken: utilsptr.To(false),
 					SecurityContext: &core.PodSecurityContext{
@@ -680,6 +684,17 @@ func (k *k3s) removeFinalizer(ctx context.Context, svc *core.Service) (*core.Ser
 	return svc, nil
 }
 
+// getPriorityClassName returns the value of the priority class name annotation on the service,
+// or the system default priority class name.
+func (k *k3s) getPriorityClassName(svc *core.Service) string {
+	if svc != nil {
+		if v, ok := svc.Annotations[priorityAnnotation]; ok {
+			return v
+		}
+	}
+	return k.LBDefaultPriorityClassName
+}
+
 // generateName generates a distinct name for the DaemonSet based on the service name and UID
 func generateName(svc *core.Service) string {
 	return fmt.Sprintf("svclb-%s-%s", svc.Name, svc.UID[:8])

pkg/daemons/control/deps/deps.go

@@ -829,6 +829,7 @@ func genEgressSelectorConfig(controlConfig *config.Control) error {
 
 func genCloudConfig(controlConfig *config.Control) error {
 	cloudConfig := cloudprovider.Config{
+		LBDefaultPriorityClassName: cloudprovider.DefaultLBPriorityClassName,
 		LBEnabled:                  !controlConfig.DisableServiceLB,
 		LBNamespace:                controlConfig.ServiceLBNamespace,
 		LBImage:                    cloudprovider.DefaultLBImage,