Simplify stale-connection detection in kube-proxy

pkg/proxy/iptables/proxier.go

@@ -48,7 +48,6 @@ import (
 	"k8s.io/kubernetes/pkg/proxy/healthcheck"
 	utilexec "k8s.io/kubernetes/pkg/util/exec"
 	utiliptables "k8s.io/kubernetes/pkg/util/iptables"
-	"k8s.io/kubernetes/pkg/util/slice"
 	utilsysctl "k8s.io/kubernetes/pkg/util/sysctl"
 	utilversion "k8s.io/kubernetes/pkg/util/version"
 )
@@ -556,15 +555,6 @@ func (proxier *Proxier) OnServiceUpdate(allServices []api.Service) {
 	proxier.deleteServiceConnections(staleUDPServices.List())
 }
 
-// Generate a list of ip strings from the list of endpoint infos
-func flattenEndpointsInfo(endPoints []*endpointsInfo) []string {
-	var endpointIPs []string
-	for _, ep := range endPoints {
-		endpointIPs = append(endpointIPs, ep.endpoint)
-	}
-	return endpointIPs
-}
-
 // Reconstruct the list of endpoint infos from the endpointIP list
 // Use the slice of endpointIPs to rebuild a slice of corresponding {endpointIP, localEndpointOnly} infos
 // from the full []hostPortInfo slice.
@@ -614,28 +604,34 @@ func (proxier *Proxier) OnEndpointsUpdate(allEndpoints []api.Endpoints) {
 
 // Convert a slice of api.Endpoints objects into a map of service-port -> endpoints.
 func updateEndpoints(allEndpoints []api.Endpoints, curMap map[proxy.ServicePortName][]*endpointsInfo, hostname string,
-	healthChecker healthChecker) (newMap map[proxy.ServicePortName][]*endpointsInfo, stale map[endpointServicePair]bool) {
+	healthChecker healthChecker) (newMap map[proxy.ServicePortName][]*endpointsInfo, staleSet map[endpointServicePair]bool) {
 
 	// return values
 	newMap = make(map[proxy.ServicePortName][]*endpointsInfo)
-	stale = make(map[endpointServicePair]bool)
+	staleSet = make(map[endpointServicePair]bool)
 
 	// local
 	svcPortToInfoMap := make(map[proxy.ServicePortName][]hostPortInfo)
 
 	// Update endpoints for services.
 	for i := range allEndpoints {
-		accumulateEndpointsMap(&allEndpoints[i], hostname, curMap, &newMap, &svcPortToInfoMap, &stale)
+		accumulateEndpointsMap(&allEndpoints[i], hostname, curMap, &newMap, &svcPortToInfoMap)
 	}
 	// Check stale connections against endpoints missing from the update.
 	// TODO: we should really only mark a connection stale if the proto was UDP
 	// and the (ip, port, proto) was removed from the endpoints.
-	for svcPort := range curMap {
-		if _, found := newMap[svcPort]; !found {
-			glog.V(3).Infof("Removing endpoints for %q", svcPort)
-			// record endpoints of unactive service to stale connections
-			for _, ep := range curMap[svcPort] {
-				stale[endpointServicePair{endpoint: ep.endpoint, servicePortName: svcPort}] = true
+	for svcPort, epList := range curMap {
+		for _, ep := range epList {
+			stale := true
+			for i := range newMap[svcPort] {
+				if *newMap[svcPort][i] == *ep {
+					stale = false
+					break
+				}
+			}
+			if stale {
+				glog.V(4).Infof("Stale endpoint %v -> %v", svcPort, ep.endpoint)
+				staleSet[endpointServicePair{endpoint: ep.endpoint, servicePortName: svcPort}] = true
 			}
 		}
 	}
@@ -652,7 +648,7 @@ func updateEndpoints(allEndpoints []api.Endpoints, curMap map[proxy.ServicePortN
 		updateHealthCheckEntries(svcPort.NamespacedName, svcPortToInfoMap[svcPort], healthChecker)
 	}
 
-	return newMap, stale
+	return newMap, staleSet
 }
 
 // Gather information about all the endpoint state for a given api.Endpoints.
@@ -667,8 +663,7 @@ func updateEndpoints(allEndpoints []api.Endpoints, curMap map[proxy.ServicePortN
 func accumulateEndpointsMap(endpoints *api.Endpoints, hostname string,
 	curEndpoints map[proxy.ServicePortName][]*endpointsInfo,
 	newEndpoints *map[proxy.ServicePortName][]*endpointsInfo,
-	svcPortToInfoMap *map[proxy.ServicePortName][]hostPortInfo,
-	staleConnections *map[endpointServicePair]bool) {
+	svcPortToInfoMap *map[proxy.ServicePortName][]hostPortInfo) {
 
 	// We need to build a map of portname -> all ip:ports for that
 	// portname.  Explode Endpoints.Subsets[*] into this structure.
@@ -694,16 +689,6 @@ func accumulateEndpointsMap(endpoints *api.Endpoints, hostname string,
 	// Decompose the lists of endpoints into details of what was changed for the caller.
 	for svcPort, hostPortInfos := range *svcPortToInfoMap {
 		newEPList := flattenValidEndpoints(hostPortInfos)
-		// Flatten the list of current endpoint infos to just a list of ips as strings
-		curEndpointIPs := flattenEndpointsInfo(curEndpoints[svcPort])
-		if len(curEndpointIPs) != len(newEPList) || !slicesEquiv(slice.CopyStrings(curEndpointIPs), newEPList) {
-			glog.V(3).Infof("Setting endpoints for %q to %+v", svcPort, newEndpoints)
-			// Gather stale connections to removed endpoints
-			removedEndpoints := getRemovedEndpoints(curEndpointIPs, newEPList)
-			for _, ep := range removedEndpoints {
-				(*staleConnections)[endpointServicePair{endpoint: ep, servicePortName: svcPort}] = true
-			}
-		}
 		glog.V(3).Infof("Setting endpoints for %q to %+v", svcPort, newEPList)
 		// Once the set operations using the list of ips are complete, build the list of endpoint infos
 		(*newEndpoints)[svcPort] = buildEndpointInfoList(hostPortInfos, newEPList)
@@ -738,17 +723,6 @@ func isValidEndpoint(hpp *hostPortInfo) bool {
 	return hpp.host != "" && hpp.port > 0
 }
 
-// Tests whether two slices are equivalent.  This sorts both slices in-place.
-func slicesEquiv(lhs, rhs []string) bool {
-	if len(lhs) != len(rhs) {
-		return false
-	}
-	if reflect.DeepEqual(slice.SortStrings(lhs), slice.SortStrings(rhs)) {
-		return true
-	}
-	return false
-}
-
 func flattenValidEndpoints(endpoints []hostPortInfo) []string {
 	// Convert Endpoint objects into strings for easier use later.
 	var result []string
@@ -803,11 +777,6 @@ func servicePortEndpointChainName(s proxy.ServicePortName, protocol string, endp
 	return utiliptables.Chain("KUBE-SEP-" + encoded[:16])
 }
 
-// getRemovedEndpoints returns the endpoint IPs that are missing in the new endpoints
-func getRemovedEndpoints(curEndpoints, newEndpoints []string) []string {
-	return sets.NewString(curEndpoints...).Difference(sets.NewString(newEndpoints...)).List()
-}
-
 type endpointServicePair struct {
 	endpoint        string
 	servicePortName proxy.ServicePortName