From a49760bfcec5cd1a59327ab1c412ecfe52f50ed0 Mon Sep 17 00:00:00 2001
From: Karan Goel <karangoel@google.com>
Date: Thu, 10 Sep 2020 09:34:16 -0700
Subject: [PATCH] Non-zero cfs quota period duration requires feature flag

---
 pkg/kubelet/apis/config/validation/BUILD        |  1 +
 .../apis/config/validation/validation.go        |  8 ++++++++
 .../apis/config/validation/validation_test.go   | 17 +++++++++++++----
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/pkg/kubelet/apis/config/validation/BUILD b/pkg/kubelet/apis/config/validation/BUILD
index 447b9d3b1a5..25ad727a0a0 100644
--- a/pkg/kubelet/apis/config/validation/BUILD
+++ b/pkg/kubelet/apis/config/validation/BUILD
@@ -19,6 +19,7 @@ go_library(
         "//pkg/kubelet/apis/config:go_default_library",
         "//pkg/kubelet/cm/cpuset:go_default_library",
         "//pkg/kubelet/types:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/errors:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/validation:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
diff --git a/pkg/kubelet/apis/config/validation/validation.go b/pkg/kubelet/apis/config/validation/validation.go
index 9afa64205e0..c42885d970b 100644
--- a/pkg/kubelet/apis/config/validation/validation.go
+++ b/pkg/kubelet/apis/config/validation/validation.go
@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"time"
 
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	utilvalidation "k8s.io/apimachinery/pkg/util/validation"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
@@ -31,6 +32,10 @@ import (
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
 )
 
+var (
+	defaultCFSQuota = metav1.Duration{Duration: 100 * time.Millisecond}
+)
+
 // ValidateKubeletConfiguration validates `kc` and returns an error if it is invalid
 func ValidateKubeletConfiguration(kc *kubeletconfig.KubeletConfiguration) error {
 	allErrors := []error{}
@@ -60,6 +65,9 @@ func ValidateKubeletConfiguration(kc *kubeletconfig.KubeletConfiguration) error
 	if kc.HealthzPort != 0 && utilvalidation.IsValidPortNum(int(kc.HealthzPort)) != nil {
 		allErrors = append(allErrors, fmt.Errorf("invalid configuration: HealthzPort (--healthz-port) %v must be between 1 and 65535, inclusive", kc.HealthzPort))
 	}
+	if !localFeatureGate.Enabled(features.CPUCFSQuotaPeriod) && kc.CPUCFSQuotaPeriod != defaultCFSQuota {
+		allErrors = append(allErrors, fmt.Errorf("invalid configuration: CPUCFSQuotaPeriod %v requires feature gate CustomCPUCFSQuotaPeriod", kc.CPUCFSQuotaPeriod))
+	}
 	if localFeatureGate.Enabled(features.CPUCFSQuotaPeriod) && utilvalidation.IsInRange(int(kc.CPUCFSQuotaPeriod.Duration), int(1*time.Microsecond), int(time.Second)) != nil {
 		allErrors = append(allErrors, fmt.Errorf("invalid configuration: CPUCFSQuotaPeriod (--cpu-cfs-quota-period) %v must be between 1usec and 1sec, inclusive", kc.CPUCFSQuotaPeriod))
 	}
diff --git a/pkg/kubelet/apis/config/validation/validation_test.go b/pkg/kubelet/apis/config/validation/validation_test.go
index 00ed0aaf268..31ab03b7015 100644
--- a/pkg/kubelet/apis/config/validation/validation_test.go
+++ b/pkg/kubelet/apis/config/validation/validation_test.go
@@ -52,7 +52,10 @@ func TestValidateKubeletConfiguration(t *testing.T) {
 		RegistryPullQPS:             5,
 		HairpinMode:                 kubeletconfig.PromiscuousBridge,
 		NodeLeaseDurationSeconds:    1,
-		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 100 * time.Millisecond},
+		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 25 * time.Millisecond},
+		FeatureGates: map[string]bool{
+			"CustomCPUCFSQuotaPeriod": true,
+		},
 	}
 	if allErrors := ValidateKubeletConfiguration(successCase1); allErrors != nil {
 		t.Errorf("expect no errors, got %v", allErrors)
@@ -84,8 +87,11 @@ func TestValidateKubeletConfiguration(t *testing.T) {
 		RegistryPullQPS:             5,
 		HairpinMode:                 kubeletconfig.PromiscuousBridge,
 		NodeLeaseDurationSeconds:    1,
-		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 100 * time.Millisecond},
+		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 50 * time.Millisecond},
 		ReservedSystemCPUs:          "0-3",
+		FeatureGates: map[string]bool{
+			"CustomCPUCFSQuotaPeriod": true,
+		},
 	}
 	if allErrors := ValidateKubeletConfiguration(successCase2); allErrors != nil {
 		t.Errorf("expect no errors, got %v", allErrors)
@@ -115,7 +121,7 @@ func TestValidateKubeletConfiguration(t *testing.T) {
 		RegistryPullQPS:             -10,
 		HairpinMode:                 "foo",
 		NodeLeaseDurationSeconds:    -1,
-		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 0},
+		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 100 * time.Millisecond},
 	}
 	const numErrsErrorCase1 = 25
 	if allErrors := ValidateKubeletConfiguration(errorCase1); len(allErrors.(utilerrors.Aggregate).Errors()) != numErrsErrorCase1 {
@@ -148,8 +154,11 @@ func TestValidateKubeletConfiguration(t *testing.T) {
 		RegistryPullQPS:             5,
 		HairpinMode:                 kubeletconfig.PromiscuousBridge,
 		NodeLeaseDurationSeconds:    1,
-		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 100 * time.Millisecond},
+		CPUCFSQuotaPeriod:           metav1.Duration{Duration: 50 * time.Millisecond},
 		ReservedSystemCPUs:          "0-3",
+		FeatureGates: map[string]bool{
+			"CustomCPUCFSQuotaPeriod": true,
+		},
 	}
 	const numErrsErrorCase2 = 1
 	if allErrors := ValidateKubeletConfiguration(errorCase2); len(allErrors.(utilerrors.Aggregate).Errors()) != numErrsErrorCase2 {