fetch busycpusImage using environment variables

This patch adds 2 env variables QE_IMAGE_REGISTRY and
BUSY_CPUS_IMAGE for QE image registry and busycpus image

This is required to execute tests in disconnected environment
where quay.io is not accessible and have to use internal private
registry

Signed-off-by: Niranjan M.R <mrniranjan@redhat.com>

test/e2e/performanceprofile/functests/1_performance/cpu_management.go

@@ -3,6 +3,7 @@ package __performance
 import (
 	"context"
 	"fmt"
+	"os"
 	"regexp"
 	"strconv"
 	"strings"
@@ -537,14 +538,15 @@ var _ = Describe("[rfe_id:27363][performance] CPU Management", Ordered, func() {
 	Context("Crio Annotations", func() {
 		var testpod *corev1.Pod
 		var allTestpods map[types.UID]*corev1.Pod
+		var busyCpusImage string
 		annotations := map[string]string{
 			"cpu-load-balancing.crio.io": "disable",
 			"cpu-quota.crio.io":          "disable",
 		}
 		BeforeAll(func() {
 			var err error
 			allTestpods = make(map[types.UID]*corev1.Pod)
-
+			busyCpusImage = busyCpuImageEnv()
 			testpod = getTestPodWithAnnotations(annotations, smtLevel)
 			// workaround for https://github.com/kubernetes/kubernetes/issues/107074
 			// until https://github.com/kubernetes/kubernetes/pull/120661 lands
@@ -576,7 +578,7 @@ var _ = Describe("[rfe_id:27363][performance] CPU Management", Ordered, func() {
 
 			By("Starting the pod")
 			testpod.Spec.NodeSelector = testutils.NodeSelectorLabels
-			testpod.Spec.Containers[0].Image = "quay.io/ocp-edge-qe/busycpus"
+			testpod.Spec.Containers[0].Image = busyCpusImage
 			testpod.Spec.Containers[0].Resources.Limits[corev1.ResourceCPU] = resource.MustParse("2")
 			err = testclient.Client.Create(context.TODO(), testpod)
 			Expect(err).ToNot(HaveOccurred())
@@ -951,3 +953,20 @@ func checkSchedulingDomains(workerRTNode *corev1.Node, podCpus cpuset.CPUSet, te
 	}).WithTimeout(2*time.Minute).WithPolling(5*time.Second).ShouldNot(HaveOccurred(), errMsg)
 
 }
+
+// busyCpuImageEnv return busycpus image used for crio quota annotations test
+// This is required for running tests on disconnected environment where images are mirrored
+// in private registries.
+func busyCpuImageEnv() string {
+	qeImageRegistry := os.Getenv("QE_IMAGE_REGISTRY")
+	busyCpusImage := os.Getenv("BUSY_CPUS_IMAGE")
+
+	if busyCpusImage == "" {
+		busyCpusImage = "busycpus"
+	}
+
+	if qeImageRegistry == "" {
+		qeImageRegistry = "quay.io/ocp-edge-qe/"
+	}
+	return fmt.Sprintf("%s%s", qeImageRegistry, busyCpusImage)
+}