Merge pull request #2407 from bitoku/o/cpu-weight

UPSTREAM: <drop>: OKD-276: Fix InPlacePodVerticalScaling tests

Author: openshift-merge-bot[bot]

test/e2e/framework/pod/resize.go

@@ -21,6 +21,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"math"
 	"strconv"
 	"strings"
 
@@ -321,16 +322,17 @@ func VerifyPodContainersCgroupValues(ctx context.Context, f *framework.Framework
 		}
 		tc := makeResizableContainer(ci)
 		if tc.Resources.Limits != nil || tc.Resources.Requests != nil {
-			var expectedCPUShares int64
+			var expectedCPUShares, v1expectedCPUShares, newExpectedCPUShares int64
 			var expectedMemLimitString string
 			expectedMemLimitInBytes := tc.Resources.Limits.Memory().Value()
 			cpuRequest := tc.Resources.Requests.Cpu()
 			cpuLimit := tc.Resources.Limits.Cpu()
 			if cpuRequest.IsZero() && !cpuLimit.IsZero() {
-				expectedCPUShares = int64(kubecm.MilliCPUToShares(cpuLimit.MilliValue()))
+				v1expectedCPUShares = int64(kubecm.MilliCPUToShares(cpuLimit.MilliValue()))
 			} else {
-				expectedCPUShares = int64(kubecm.MilliCPUToShares(cpuRequest.MilliValue()))
+				v1expectedCPUShares = int64(kubecm.MilliCPUToShares(cpuRequest.MilliValue()))
 			}
+			expectedCPUShares = v1expectedCPUShares
 
 			expectedCPULimits := GetCPULimitCgroupExpectations(cpuLimit)
 			expectedMemLimitString = strconv.FormatInt(expectedMemLimitInBytes, 10)
@@ -340,21 +342,52 @@ func VerifyPodContainersCgroupValues(ctx context.Context, f *framework.Framework
 				}
 				// convert cgroup v1 cpu.shares value to cgroup v2 cpu.weight value
 				// https://github.com/kubernetes/enhancements/tree/master/keps/sig-node/2254-cgroup-v2#phase-1-convert-from-cgroups-v1-settings-to-v2
-				expectedCPUShares = int64(1 + ((expectedCPUShares-2)*9999)/262142)
+				expectedCPUShares = int64(1 + ((v1expectedCPUShares-2)*9999)/262142)
+				// TODO(atokubi): This is required to fix https://github.com/kubernetes/kubernetes/pull/132791
+				//    This should be dropped in 4.21, because 4.21(=1.34) fix would be a carry pulled from 1.35
+				newExpectedCPUShares = ConvertCPUSharesToCgroupV2Value(v1expectedCPUShares)
 			}
 
 			if expectedMemLimitString != "0" {
 				errs = append(errs, VerifyCgroupValue(f, pod, ci.Name, cgroupMemLimit, expectedMemLimitString))
 			}
 			errs = append(errs, VerifyCgroupValue(f, pod, ci.Name, cgroupCPULimit, expectedCPULimits...))
-			errs = append(errs, VerifyCgroupValue(f, pod, ci.Name, cgroupCPURequest, strconv.FormatInt(expectedCPUShares, 10)))
+			errs = append(errs, VerifyCgroupValue(f, pod, ci.Name, cgroupCPURequest, strconv.FormatInt(expectedCPUShares, 10), strconv.FormatInt(newExpectedCPUShares, 10)))
 			// TODO(vinaykul,InPlacePodVerticalScaling): Verify oom_score_adj when runc adds support for updating it
 			// See https://github.com/opencontainers/runc/pull/4669
 		}
 	}
 	return utilerrors.NewAggregate(errs)
 }
 
+// ConvertCPUSharesToCgroupV2Value converts CPU shares, used by cgroup v1,
+// to CPU weight, used by cgroup v2.
+//
+// Cgroup v1 CPU shares has a range of [2^1...2^18], i.e. [2...262144],
+// and the default value is 1024.
+//
+// Cgroup v2 CPU weight has a range of [10^0...10^4], i.e. [1...10000],
+// and the default value is 100.
+//
+// This function is identical to https://github.com/opencontainers/cgroups/blob/a3e2ecd1f756a19cee15f85b96337a59c3b5337b/utils.go#L417-L441
+func ConvertCPUSharesToCgroupV2Value(cpuShares int64) int64 {
+	// The value of 0 means "unset".
+	if cpuShares == 0 {
+		return 0
+	}
+	if cpuShares <= 2 {
+		return 1
+	}
+	if cpuShares >= 262144 {
+		return 10000
+	}
+	l := math.Log2(float64(cpuShares))
+	// Quadratic function which fits min, max, and default.
+	exponent := (l*l+125*l)/612.0 - 7.0/34.0
+
+	return int64(math.Ceil(math.Pow(10, exponent)))
+}
+
 func verifyPodRestarts(f *framework.Framework, pod *v1.Pod, wantInfo []ResizableContainerInfo) error {
 	ginkgo.GinkgoHelper()