Changes to latency-profile-observer,controller

- use a slice for suppress fns in NewLatencyProfileObserver
- add new suppressor fn: NewSuppressConfigUpdateForExtremeProfilesFunc
- add checkRejectFn in controller to update status when rejection occurs

Signed-off-by: Swarup Ghosh <swghosh@redhat.com>

pkg/operator/configobserver/node/helpers.go

@@ -0,0 +1,89 @@
+package node
+
+import (
+	"reflect"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+
+	configv1 "github.com/openshift/api/config/v1"
+	v1 "github.com/openshift/api/operator/v1"
+)
+
+// GetUsedLatencyConfigPaths is used to get list of config paths that were used for latency profiles
+func GetUsedLatencyConfigPaths(latencyConfigs []LatencyConfigProfileTuple) [][]string {
+	usedConfigPaths := make([][]string, len(latencyConfigs))
+	for i, latencyConfig := range latencyConfigs {
+		usedConfigPaths[i] = latencyConfig.ConfigPath
+	}
+	return usedConfigPaths
+}
+
+// GenerateConfigsForEachLatencyProfile is used to generate config for each latency profile using known arg val pairs provided in latencyConfigs
+func GenerateConfigsForEachLatencyProfile(latencyConfigs []LatencyConfigProfileTuple) (profileConfigs map[configv1.WorkerLatencyProfileType]map[string]interface{}, err error) {
+	profileConfigs = make(map[configv1.WorkerLatencyProfileType]map[string]interface{})
+	// traverse along each latency config to construct a config arg val map for each known profile
+	for _, latencyConfig := range latencyConfigs {
+		for profile := range latencyConfig.ProfileConfigValues {
+			profileValue := latencyConfig.ProfileConfigValues[profile]
+
+			if _, ok := profileConfigs[profile]; !ok {
+				profileConfigs[profile] = make(map[string]interface{})
+			}
+			err = unstructured.SetNestedStringSlice(profileConfigs[profile], []string{profileValue}, latencyConfig.ConfigPath...)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+	return profileConfigs, nil
+}
+
+// ShouldRejectProfileTransition is used to determine the profile passed in fromLatencyConfig
+// (fromLatencyConfig should be config that already has only usedLatencyConfigPaths pruned)
+// and in case the transition fromProfile -> toProfile is one of the rejected scenarios, reject it
+// i.e. isRejected flag will be true
+func ShouldRejectProfileTransition(
+	fromLatencyConfig map[string]interface{}, toProfile configv1.WorkerLatencyProfileType,
+	knownProfileConfigs map[configv1.WorkerLatencyProfileType]map[string]interface{},
+	profileRejectionScenarios []LatencyProfileRejectionScenario,
+) (isRejected bool, fromProfile configv1.WorkerLatencyProfileType) {
+	// determine which profile was in the already pruned config
+	for profile := range knownProfileConfigs {
+		if reflect.DeepEqual(fromLatencyConfig, knownProfileConfigs[profile]) {
+			fromProfile = profile
+			break
+		}
+	} // fromProfile can be "" at this point
+
+	// check from/to profile if it is one of the rejection scenarios,
+	// suppress=true, else suppress=false
+	for _, rejectionScenario := range profileRejectionScenarios {
+		if fromProfile == rejectionScenario.FromProfile && toProfile == rejectionScenario.ToProfile {
+			// reject = True
+			return true, fromProfile
+		}
+	}
+	return false, fromProfile
+}
+
+// IsDayZero returns true when currentRevisions is empty or
+// when all current revision equal to 0
+func IsDayZero(currentRevisions []int32) bool {
+	for _, revision := range currentRevisions {
+		if revision != 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// isDayZeroFromStatus is a wrapper around IsDayZero that collects currentRevisions
+// from operator nodeStatuses to return true when all revisions are 0 or when
+// nodeStatuses are not reported yet
+func isDayZeroFromStatus(operatorStatus *v1.StaticPodOperatorStatus) bool {
+	currentRevisions := make([]int32, len(operatorStatus.NodeStatuses))
+	for i, nodeStatus := range operatorStatus.NodeStatuses {
+		currentRevisions[i] = nodeStatus.CurrentRevision
+	}
+	return IsDayZero(currentRevisions)
+}