fix bugs of container cpu shares when cpu request set to zero

pkg/kubelet/kuberuntime/kuberuntime_container_linux.go

@@ -63,7 +63,11 @@ func (m *kubeGenericRuntimeManager) generateLinuxContainerConfig(container *v1.C
 	}
 
 	// set linux container resources
-	lc.Resources = m.calculateLinuxResources(container.Resources.Requests.Cpu(), container.Resources.Limits.Cpu(), container.Resources.Limits.Memory())
+	var cpuRequest *resource.Quantity
+	if _, cpuRequestExists := container.Resources.Requests[v1.ResourceCPU]; cpuRequestExists {
+		cpuRequest = container.Resources.Requests.Cpu()
+	}
+	lc.Resources = m.calculateLinuxResources(cpuRequest, container.Resources.Limits.Cpu(), container.Resources.Limits.Memory())
 
 	lc.Resources.OomScoreAdj = int64(qos.GetContainerOOMScoreAdjust(pod, container,
 		int64(m.machineInfo.MemoryCapacity)))
@@ -138,9 +142,9 @@ func (m *kubeGenericRuntimeManager) calculateLinuxResources(cpuRequest, cpuLimit
 	// If request is not specified, but limit is, we want request to default to limit.
 	// API server does this for new containers, but we repeat this logic in Kubelet
 	// for containers running on existing Kubernetes clusters.
-	if cpuRequest.IsZero() && !cpuLimit.IsZero() {
+	if cpuRequest == nil && !cpuLimit.IsZero() {
 		cpuShares = int64(cm.MilliCPUToShares(cpuLimit.MilliValue()))
-	} else {
+	} else if cpuRequest != nil {
 		// if cpuRequest.Amount is nil, then MilliCPUToShares will return the minimal number
 		// of CPU shares.
 		cpuShares = int64(cm.MilliCPUToShares(cpuRequest.MilliValue()))

pkg/kubelet/kuberuntime/kuberuntime_container_linux_test.go

@@ -260,6 +260,29 @@ func TestCalculateLinuxResources(t *testing.T) {
 				MemoryLimitInBytes: 0,
 			},
 		},
+		{
+			name:   "RequestNilCPU",
+			cpuLim: resource.MustParse("2"),
+			memLim: resource.MustParse("0"),
+			expected: &runtimeapi.LinuxContainerResources{
+				CpuPeriod:          100000,
+				CpuQuota:           200000,
+				CpuShares:          2048,
+				MemoryLimitInBytes: 0,
+			},
+		},
+		{
+			name:   "RequestZeroCPU",
+			cpuReq: resource.MustParse("0"),
+			cpuLim: resource.MustParse("2"),
+			memLim: resource.MustParse("0"),
+			expected: &runtimeapi.LinuxContainerResources{
+				CpuPeriod:          100000,
+				CpuQuota:           200000,
+				CpuShares:          2,
+				MemoryLimitInBytes: 0,
+			},
+		},
 	}
 	for _, test := range tests {
 		linuxContainerResources := m.calculateLinuxResources(&test.cpuReq, &test.cpuLim, &test.memLim)

pkg/kubelet/kuberuntime/kuberuntime_sandbox_linux.go

@@ -21,6 +21,7 @@ package kuberuntime
 
 import (
 	v1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1"
 	resourcehelper "k8s.io/kubernetes/pkg/api/v1/resource"
 )
@@ -41,7 +42,11 @@ func (m *kubeGenericRuntimeManager) convertOverheadToLinuxResources(pod *v1.Pod)
 
 func (m *kubeGenericRuntimeManager) calculateSandboxResources(pod *v1.Pod) *runtimeapi.LinuxContainerResources {
 	req, lim := resourcehelper.PodRequestsAndLimitsWithoutOverhead(pod)
-	return m.calculateLinuxResources(req.Cpu(), lim.Cpu(), lim.Memory())
+	var cpuRequest *resource.Quantity
+	if _, cpuRequestExists := req[v1.ResourceCPU]; cpuRequestExists {
+		cpuRequest = req.Cpu()
+	}
+	return m.calculateLinuxResources(cpuRequest, lim.Cpu(), lim.Memory())
 }
 
 func (m *kubeGenericRuntimeManager) applySandboxResources(pod *v1.Pod, config *runtimeapi.PodSandboxConfig) error {