refactor podCIDR handling in kubelet to runtime state

pkg/kubelet/kubelet.go

@@ -32,7 +32,6 @@ import (
 	"path/filepath"
 	"sort"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/golang/glog"
@@ -278,7 +277,7 @@ func NewMainKubelet(
 		clusterDNS:                     clusterDNS,
 		serviceLister:                  serviceLister,
 		nodeLister:                     nodeLister,
-		runtimeState:                   newRuntimeState(maxWaitForContainerRuntime),
+		runtimeState:                   newRuntimeState(maxWaitForContainerRuntime, configureCBR0, podCIDR),
 		masterServiceNamespace:         masterServiceNamespace,
 		streamingConnectionIdleTimeout: streamingConnectionIdleTimeout,
 		recorder:                       recorder,
@@ -297,7 +296,6 @@ func NewMainKubelet(
 		chownRunner:                    chownRunner,
 		writer:                         writer,
 		configureCBR0:                  configureCBR0,
-		podCIDR:                        podCIDR,
 		reconcileCIDR:                  reconcileCIDR,
 		pods:                           pods,
 		syncLoopMonitor:                util.AtomicValue{},
@@ -499,8 +497,7 @@ type Kubelet struct {
 
 	// Last timestamp when runtime responded on ping.
 	// Mutex is used to protect this value.
-	runtimeState       *runtimeState
+	runtimeState *runtimeState
-	networkConfigMutex sync.Mutex
 
 	// Volume plugins.
 	volumePluginMgr volume.VolumePluginMgr
@@ -588,7 +585,6 @@ type Kubelet struct {
 	// Whether or not kubelet should take responsibility for keeping cbr0 in
 	// the correct state.
 	configureCBR0 bool
-	podCIDR       string
 	reconcileCIDR bool
 
 	// Number of Pods which can be run by this Kubelet
@@ -2425,9 +2421,7 @@ func (kl *Kubelet) syncNetworkStatus() {
 			err = fmt.Errorf("Error on adding ip table rules: %v", err)
 			glog.Error(err)
 		}
-		kl.networkConfigMutex.Lock()
+		podCIDR := kl.runtimeState.podCIDR()
-		podCIDR := kl.podCIDR
-		kl.networkConfigMutex.Unlock()
 		if len(podCIDR) == 0 {
 			err = fmt.Errorf("ConfigureCBR0 requested, but PodCIDR not set. Will not configure CBR0 right now")
 			glog.Warning(err)
@@ -2694,11 +2688,9 @@ func (kl *Kubelet) tryUpdateNodeStatus() error {
 	if node == nil {
 		return fmt.Errorf("no node instance returned for %q", kl.nodeName)
 	}
-	kl.networkConfigMutex.Lock()
 	if kl.reconcileCIDR {
-		kl.podCIDR = node.Spec.PodCIDR
+		kl.runtimeState.setPodCIDR(node.Spec.PodCIDR)
 	}
-	kl.networkConfigMutex.Unlock()
 
 	if err := kl.setNodeStatus(node); err != nil {
 		return err

pkg/kubelet/kubelet_test.go

@@ -96,7 +96,7 @@ func newTestKubelet(t *testing.T) *TestKubelet {
 
 	kubelet.hostname = testKubeletHostname
 	kubelet.nodeName = testKubeletHostname
-	kubelet.runtimeState = newRuntimeState(maxWaitForContainerRuntime)
+	kubelet.runtimeState = newRuntimeState(maxWaitForContainerRuntime, false, "" /* Pod CIDR */)
 	kubelet.networkPlugin, _ = network.InitNetworkPlugin([]network.NetworkPlugin{}, "", network.NewFakeHost(nil))
 	if tempDir, err := ioutil.TempDir("/tmp", "kubelet_test."); err != nil {
 		t.Fatalf("can't make a temp rootdir: %v", err)
@@ -139,8 +139,7 @@ func newTestKubelet(t *testing.T) *TestKubelet {
 	kubelet.livenessManager = proberesults.NewManager()
 
 	kubelet.volumeManager = newVolumeManager()
-	kubelet.containerManager, _ = newContainerManager(fakeContainerMgrMountInt(), mockCadvisor, "", "", "")
+	kubelet.containerManager = cm.NewStubContainerManager()
-	kubelet.runtimeState.setNetworkState(nil)
 	fakeClock := &util.FakeClock{Time: time.Now()}
 	kubelet.backOff = util.NewBackOff(time.Second, time.Minute)
 	kubelet.backOff.Clock = fakeClock
@@ -2996,8 +2995,7 @@ func TestUpdateNodeStatusWithoutContainerRuntime(t *testing.T) {
 			},
 		},
 	}
-	kubelet.runtimeState = newRuntimeState(time.Duration(0))
+	kubelet.runtimeState = newRuntimeState(time.Duration(0), false, "" /* Pod CIDR */)
-	kubelet.runtimeState.setNetworkState(nil)
 	kubelet.updateRuntimeUp()
 	if err := kubelet.updateNodeStatus(); err != nil {
 		t.Errorf("unexpected error: %v", err)

pkg/kubelet/runtime.go

@@ -27,6 +27,7 @@ type runtimeState struct {
 	lastBaseRuntimeSync      time.Time
 	baseRuntimeSyncThreshold time.Duration
 	networkError             error
+	cidr                     string
 	initError                error
 }
 
@@ -42,6 +43,18 @@ func (s *runtimeState) setNetworkState(err error) {
 	s.networkError = err
 }
 
+func (s *runtimeState) setPodCIDR(cidr string) {
+	s.Lock()
+	defer s.Unlock()
+	s.cidr = cidr
+}
+
+func (s *runtimeState) podCIDR() string {
+	s.Lock()
+	defer s.Unlock()
+	return s.cidr
+}
+
 func (s *runtimeState) setInitError(err error) {
 	s.Lock()
 	defer s.Unlock()
@@ -64,10 +77,15 @@ func (s *runtimeState) errors() []string {
 	return ret
 }
 
-func newRuntimeState(runtimeSyncThreshold time.Duration) *runtimeState {
+func newRuntimeState(runtimeSyncThreshold time.Duration, configureNetwork bool, cidr string) *runtimeState {
+	var networkError error = nil
+	if configureNetwork {
+		networkError = fmt.Errorf("network state unknown")
+	}
 	return &runtimeState{
 		lastBaseRuntimeSync:      time.Time{},
 		baseRuntimeSyncThreshold: runtimeSyncThreshold,
-		networkError:             fmt.Errorf("network state unknown"),
+		networkError:             networkError,
+		cidr:                     cidr,
 	}
 }