rebase: update K8s packages to v0.32.1

Update K8s packages in go.mod to v0.32.1

Signed-off-by: Praveen M <m.praveen@ibm.com>

vendor/k8s.io/kubernetes/pkg/scheduler/backend/queue/active_queue.go

@@ -0,0 +1,415 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package queue
+
+import (
+	"container/list"
+	"fmt"
+	"sync"
+
+	v1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/klog/v2"
+	"k8s.io/kubernetes/pkg/scheduler/backend/heap"
+	"k8s.io/kubernetes/pkg/scheduler/framework"
+	"k8s.io/kubernetes/pkg/scheduler/metrics"
+)
+
+// activeQueuer is a wrapper for activeQ related operations.
+// Its methods, except "unlocked" ones, take the lock inside.
+// Note: be careful when using unlocked() methods.
+// getLock() methods should be used only for unlocked() methods
+// and it is forbidden to call any other activeQueuer's method under this lock.
+type activeQueuer interface {
+	underLock(func(unlockedActiveQ unlockedActiveQueuer))
+	underRLock(func(unlockedActiveQ unlockedActiveQueueReader))
+
+	update(newPod *v1.Pod, oldPodInfo *framework.QueuedPodInfo) *framework.QueuedPodInfo
+	delete(pInfo *framework.QueuedPodInfo) error
+	pop(logger klog.Logger) (*framework.QueuedPodInfo, error)
+	list() []*v1.Pod
+	len() int
+	has(pInfo *framework.QueuedPodInfo) bool
+
+	listInFlightEvents() []interface{}
+	listInFlightPods() []*v1.Pod
+	clusterEventsForPod(logger klog.Logger, pInfo *framework.QueuedPodInfo) ([]*clusterEvent, error)
+	addEventsIfPodInFlight(oldPod, newPod *v1.Pod, events []framework.ClusterEvent) bool
+	addEventIfAnyInFlight(oldObj, newObj interface{}, event framework.ClusterEvent) bool
+
+	schedulingCycle() int64
+	done(pod types.UID)
+	close()
+	broadcast()
+}
+
+// unlockedActiveQueuer defines activeQ methods that are not protected by the lock itself.
+// underLock() method should be used to protect these methods.
+type unlockedActiveQueuer interface {
+	unlockedActiveQueueReader
+	AddOrUpdate(pInfo *framework.QueuedPodInfo)
+}
+
+// unlockedActiveQueueReader defines activeQ read-only methods that are not protected by the lock itself.
+// underLock() or underRLock() method should be used to protect these methods.
+type unlockedActiveQueueReader interface {
+	Get(pInfo *framework.QueuedPodInfo) (*framework.QueuedPodInfo, bool)
+	Has(pInfo *framework.QueuedPodInfo) bool
+}
+
+// activeQueue implements activeQueuer. All of the fields have to be protected using the lock.
+type activeQueue struct {
+	// lock synchronizes all operations related to activeQ.
+	// It protects activeQ, inFlightPods, inFlightEvents, schedulingCycle and closed fields.
+	// Caution: DO NOT take "SchedulingQueue.lock" after taking "lock".
+	// You should always take "SchedulingQueue.lock" first, otherwise the queue could end up in deadlock.
+	// "lock" should not be taken after taking "nLock".
+	// Correct locking order is: SchedulingQueue.lock > lock > nominator.nLock.
+	lock sync.RWMutex
+
+	// activeQ is heap structure that scheduler actively looks at to find pods to
+	// schedule. Head of heap is the highest priority pod.
+	queue *heap.Heap[*framework.QueuedPodInfo]
+
+	// cond is a condition that is notified when the pod is added to activeQ.
+	// It is used with lock.
+	cond sync.Cond
+
+	// inFlightPods holds the UID of all pods which have been popped out for which Done
+	// hasn't been called yet - in other words, all pods that are currently being
+	// processed (being scheduled, in permit, or in the binding cycle).
+	//
+	// The values in the map are the entry of each pod in the inFlightEvents list.
+	// The value of that entry is the *v1.Pod at the time that scheduling of that
+	// pod started, which can be useful for logging or debugging.
+	inFlightPods map[types.UID]*list.Element
+
+	// inFlightEvents holds the events received by the scheduling queue
+	// (entry value is clusterEvent) together with in-flight pods (entry
+	// value is *v1.Pod). Entries get added at the end while the mutex is
+	// locked, so they get serialized.
+	//
+	// The pod entries are added in Pop and used to track which events
+	// occurred after the pod scheduling attempt for that pod started.
+	// They get removed when the scheduling attempt is done, at which
+	// point all events that occurred in the meantime are processed.
+	//
+	// After removal of a pod, events at the start of the list are no
+	// longer needed because all of the other in-flight pods started
+	// later. Those events can be removed.
+	inFlightEvents *list.List
+
+	// schedCycle represents sequence number of scheduling cycle and is incremented
+	// when a pod is popped.
+	schedCycle int64
+
+	// closed indicates that the queue is closed.
+	// It is mainly used to let Pop() exit its control loop while waiting for an item.
+	closed bool
+
+	// isSchedulingQueueHintEnabled indicates whether the feature gate for the scheduling queue is enabled.
+	isSchedulingQueueHintEnabled bool
+
+	metricsRecorder metrics.MetricAsyncRecorder
+}
+
+func newActiveQueue(queue *heap.Heap[*framework.QueuedPodInfo], isSchedulingQueueHintEnabled bool, metricRecorder metrics.MetricAsyncRecorder) *activeQueue {
+	aq := &activeQueue{
+		queue:                        queue,
+		inFlightPods:                 make(map[types.UID]*list.Element),
+		inFlightEvents:               list.New(),
+		isSchedulingQueueHintEnabled: isSchedulingQueueHintEnabled,
+		metricsRecorder:              metricRecorder,
+	}
+	aq.cond.L = &aq.lock
+
+	return aq
+}
+
+// underLock runs the fn function under the lock.Lock.
+// fn can run unlockedActiveQueuer methods but should NOT run any other activeQueue method,
+// as it would end up in deadlock.
+func (aq *activeQueue) underLock(fn func(unlockedActiveQ unlockedActiveQueuer)) {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+	fn(aq.queue)
+}
+
+// underLock runs the fn function under the lock.RLock.
+// fn can run unlockedActiveQueueReader methods but should NOT run any other activeQueue method,
+// as it would end up in deadlock.
+func (aq *activeQueue) underRLock(fn func(unlockedActiveQ unlockedActiveQueueReader)) {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	fn(aq.queue)
+}
+
+// update updates the pod in activeQ if oldPodInfo is already in the queue.
+// It returns new pod info if updated, nil otherwise.
+func (aq *activeQueue) update(newPod *v1.Pod, oldPodInfo *framework.QueuedPodInfo) *framework.QueuedPodInfo {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	if pInfo, exists := aq.queue.Get(oldPodInfo); exists {
+		_ = pInfo.Update(newPod)
+		aq.queue.AddOrUpdate(pInfo)
+		return pInfo
+	}
+	return nil
+}
+
+// delete deletes the pod info from activeQ.
+func (aq *activeQueue) delete(pInfo *framework.QueuedPodInfo) error {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	return aq.queue.Delete(pInfo)
+}
+
+// pop removes the head of the queue and returns it.
+// It blocks if the queue is empty and waits until a new item is added to the queue.
+// It increments scheduling cycle when a pod is popped.
+func (aq *activeQueue) pop(logger klog.Logger) (*framework.QueuedPodInfo, error) {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	return aq.unlockedPop(logger)
+}
+
+func (aq *activeQueue) unlockedPop(logger klog.Logger) (*framework.QueuedPodInfo, error) {
+	for aq.queue.Len() == 0 {
+		// When the queue is empty, invocation of Pop() is blocked until new item is enqueued.
+		// When Close() is called, the p.closed is set and the condition is broadcast,
+		// which causes this loop to continue and return from the Pop().
+		if aq.closed {
+			logger.V(2).Info("Scheduling queue is closed")
+			return nil, nil
+		}
+		aq.cond.Wait()
+	}
+	pInfo, err := aq.queue.Pop()
+	if err != nil {
+		return nil, err
+	}
+	pInfo.Attempts++
+	// In flight, no concurrent events yet.
+	if aq.isSchedulingQueueHintEnabled {
+		// If the pod is already in the map, we shouldn't overwrite the inFlightPods otherwise it'd lead to a memory leak.
+		// https://github.com/kubernetes/kubernetes/pull/127016
+		if _, ok := aq.inFlightPods[pInfo.Pod.UID]; ok {
+			// Just report it as an error, but no need to stop the scheduler
+			// because it likely doesn't cause any visible issues from the scheduling perspective.
+			logger.Error(nil, "the same pod is tracked in multiple places in the scheduler, and just discard it", "pod", klog.KObj(pInfo.Pod))
+			// Just ignore/discard this duplicated pod and try to pop the next one.
+			return aq.unlockedPop(logger)
+		}
+
+		aq.metricsRecorder.ObserveInFlightEventsAsync(metrics.PodPoppedInFlightEvent, 1, false)
+		aq.inFlightPods[pInfo.Pod.UID] = aq.inFlightEvents.PushBack(pInfo.Pod)
+	}
+	aq.schedCycle++
+
+	// Update metrics and reset the set of unschedulable plugins for the next attempt.
+	for plugin := range pInfo.UnschedulablePlugins.Union(pInfo.PendingPlugins) {
+		metrics.UnschedulableReason(plugin, pInfo.Pod.Spec.SchedulerName).Dec()
+	}
+	pInfo.UnschedulablePlugins.Clear()
+	pInfo.PendingPlugins.Clear()
+
+	return pInfo, nil
+}
+
+// list returns all pods that are in the queue.
+func (aq *activeQueue) list() []*v1.Pod {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	var result []*v1.Pod
+	for _, pInfo := range aq.queue.List() {
+		result = append(result, pInfo.Pod)
+	}
+	return result
+}
+
+// len returns length of the queue.
+func (aq *activeQueue) len() int {
+	return aq.queue.Len()
+}
+
+// has inform if pInfo exists in the queue.
+func (aq *activeQueue) has(pInfo *framework.QueuedPodInfo) bool {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	return aq.queue.Has(pInfo)
+}
+
+// listInFlightEvents returns all inFlightEvents.
+func (aq *activeQueue) listInFlightEvents() []interface{} {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	var values []interface{}
+	for event := aq.inFlightEvents.Front(); event != nil; event = event.Next() {
+		values = append(values, event.Value)
+	}
+	return values
+}
+
+// listInFlightPods returns all inFlightPods.
+func (aq *activeQueue) listInFlightPods() []*v1.Pod {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	var pods []*v1.Pod
+	for _, obj := range aq.inFlightPods {
+		pods = append(pods, obj.Value.(*v1.Pod))
+	}
+	return pods
+}
+
+// clusterEventsForPod gets all cluster events that have happened during pod for pInfo is being scheduled.
+func (aq *activeQueue) clusterEventsForPod(logger klog.Logger, pInfo *framework.QueuedPodInfo) ([]*clusterEvent, error) {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	logger.V(5).Info("Checking events for in-flight pod", "pod", klog.KObj(pInfo.Pod), "unschedulablePlugins", pInfo.UnschedulablePlugins, "inFlightEventsSize", aq.inFlightEvents.Len(), "inFlightPodsSize", len(aq.inFlightPods))
+
+	// AddUnschedulableIfNotPresent is called with the Pod at the end of scheduling or binding.
+	// So, given pInfo should have been Pop()ed before,
+	// we can assume pInfo must be recorded in inFlightPods and thus inFlightEvents.
+	inFlightPod, ok := aq.inFlightPods[pInfo.Pod.UID]
+	if !ok {
+		return nil, fmt.Errorf("in flight Pod isn't found in the scheduling queue. If you see this error log, it's likely a bug in the scheduler")
+	}
+
+	var events []*clusterEvent
+	for event := inFlightPod.Next(); event != nil; event = event.Next() {
+		e, ok := event.Value.(*clusterEvent)
+		if !ok {
+			// Must be another in-flight Pod (*v1.Pod). Can be ignored.
+			continue
+		}
+		events = append(events, e)
+	}
+	return events, nil
+}
+
+// addEventsIfPodInFlight adds clusterEvent to inFlightEvents if the newPod is in inFlightPods.
+// It returns true if pushed the event to the inFlightEvents.
+func (aq *activeQueue) addEventsIfPodInFlight(oldPod, newPod *v1.Pod, events []framework.ClusterEvent) bool {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	_, ok := aq.inFlightPods[newPod.UID]
+	if ok {
+		for _, event := range events {
+			aq.metricsRecorder.ObserveInFlightEventsAsync(event.Label(), 1, false)
+			aq.inFlightEvents.PushBack(&clusterEvent{
+				event:  event,
+				oldObj: oldPod,
+				newObj: newPod,
+			})
+		}
+	}
+	return ok
+}
+
+// addEventIfAnyInFlight adds clusterEvent to inFlightEvents if any pod is in inFlightPods.
+// It returns true if pushed the event to the inFlightEvents.
+func (aq *activeQueue) addEventIfAnyInFlight(oldObj, newObj interface{}, event framework.ClusterEvent) bool {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	if len(aq.inFlightPods) != 0 {
+		aq.metricsRecorder.ObserveInFlightEventsAsync(event.Label(), 1, false)
+		aq.inFlightEvents.PushBack(&clusterEvent{
+			event:  event,
+			oldObj: oldObj,
+			newObj: newObj,
+		})
+		return true
+	}
+	return false
+}
+
+func (aq *activeQueue) schedulingCycle() int64 {
+	aq.lock.RLock()
+	defer aq.lock.RUnlock()
+	return aq.schedCycle
+}
+
+// done must be called for pod returned by Pop. This allows the queue to
+// keep track of which pods are currently being processed.
+func (aq *activeQueue) done(pod types.UID) {
+	aq.lock.Lock()
+	defer aq.lock.Unlock()
+
+	inFlightPod, ok := aq.inFlightPods[pod]
+	if !ok {
+		// This Pod is already done()ed.
+		return
+	}
+	delete(aq.inFlightPods, pod)
+
+	// Remove the pod from the list.
+	aq.inFlightEvents.Remove(inFlightPod)
+
+	aggrMetricsCounter := map[string]int{}
+	// Remove events which are only referred to by this Pod
+	// so that the inFlightEvents list doesn't grow infinitely.
+	// If the pod was at the head of the list, then all
+	// events between it and the next pod are no longer needed
+	// and can be removed.
+	for {
+		e := aq.inFlightEvents.Front()
+		if e == nil {
+			// Empty list.
+			break
+		}
+		ev, ok := e.Value.(*clusterEvent)
+		if !ok {
+			// A pod, must stop pruning.
+			break
+		}
+		aq.inFlightEvents.Remove(e)
+		aggrMetricsCounter[ev.event.Label()]--
+	}
+
+	for evLabel, count := range aggrMetricsCounter {
+		aq.metricsRecorder.ObserveInFlightEventsAsync(evLabel, float64(count), false)
+	}
+
+	aq.metricsRecorder.ObserveInFlightEventsAsync(metrics.PodPoppedInFlightEvent, -1,
+		// If it's the last Pod in inFlightPods, we should force-flush the metrics.
+		// Otherwise, especially in small clusters, which don't get a new Pod frequently,
+		// the metrics might not be flushed for a long time.
+		len(aq.inFlightPods) == 0)
+}
+
+// close closes the activeQueue.
+func (aq *activeQueue) close() {
+	// We should call done() for all in-flight pods to clean up the inFlightEvents metrics.
+	// It's safe even if the binding cycle running asynchronously calls done() afterwards
+	// done() will just be a no-op.
+	for pod := range aq.inFlightPods {
+		aq.done(pod)
+	}
+	aq.lock.Lock()
+	aq.closed = true
+	aq.lock.Unlock()
+}
+
+// broadcast notifies the pop() operation that new pod(s) was added to the activeQueue.
+func (aq *activeQueue) broadcast() {
+	aq.cond.Broadcast()
+}

vendor/k8s.io/kubernetes/pkg/scheduler/backend/queue/nominator.go

@@ -0,0 +1,195 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package queue
+
+import (
+	"slices"
+	"sync"
+
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+	listersv1 "k8s.io/client-go/listers/core/v1"
+	"k8s.io/klog/v2"
+	"k8s.io/kubernetes/pkg/scheduler/framework"
+)
+
+// nominator is a structure that stores pods nominated to run on nodes.
+// It exists because nominatedNodeName of pod objects stored in the structure
+// may be different than what scheduler has here. We should be able to find pods
+// by their UID and update/delete them.
+type nominator struct {
+	// nLock synchronizes all operations related to nominator.
+	// It should not be used anywhere else.
+	// Caution: DO NOT take ("SchedulingQueue.lock" or "activeQueue.lock") after taking "nLock".
+	// You should always take "SchedulingQueue.lock" and "activeQueue.lock" first,
+	// otherwise the nominator could end up in deadlock.
+	// Correct locking order is: SchedulingQueue.lock > activeQueue.lock > nLock.
+	nLock sync.RWMutex
+
+	// podLister is used to verify if the given pod is alive.
+	podLister listersv1.PodLister
+	// nominatedPods is a map keyed by a node name and the value is a list of
+	// pods which are nominated to run on the node. These are pods which can be in
+	// the activeQ or unschedulablePods.
+	nominatedPods map[string][]podRef
+	// nominatedPodToNode is map keyed by a Pod UID to the node name where it is
+	// nominated.
+	nominatedPodToNode map[types.UID]string
+}
+
+func newPodNominator(podLister listersv1.PodLister) *nominator {
+	return &nominator{
+		podLister:          podLister,
+		nominatedPods:      make(map[string][]podRef),
+		nominatedPodToNode: make(map[types.UID]string),
+	}
+}
+
+// AddNominatedPod adds a pod to the nominated pods of the given node.
+// This is called during the preemption process after a node is nominated to run
+// the pod. We update the structure before sending a request to update the pod
+// object to avoid races with the following scheduling cycles.
+func (npm *nominator) AddNominatedPod(logger klog.Logger, pi *framework.PodInfo, nominatingInfo *framework.NominatingInfo) {
+	npm.nLock.Lock()
+	npm.addNominatedPodUnlocked(logger, pi, nominatingInfo)
+	npm.nLock.Unlock()
+}
+
+func (npm *nominator) addNominatedPodUnlocked(logger klog.Logger, pi *framework.PodInfo, nominatingInfo *framework.NominatingInfo) {
+	// Always delete the pod if it already exists, to ensure we never store more than
+	// one instance of the pod.
+	npm.deleteUnlocked(pi.Pod)
+
+	var nodeName string
+	if nominatingInfo.Mode() == framework.ModeOverride {
+		nodeName = nominatingInfo.NominatedNodeName
+	} else if nominatingInfo.Mode() == framework.ModeNoop {
+		if pi.Pod.Status.NominatedNodeName == "" {
+			return
+		}
+		nodeName = pi.Pod.Status.NominatedNodeName
+	}
+
+	if npm.podLister != nil {
+		// If the pod was removed or if it was already scheduled, don't nominate it.
+		updatedPod, err := npm.podLister.Pods(pi.Pod.Namespace).Get(pi.Pod.Name)
+		if err != nil {
+			logger.V(4).Info("Pod doesn't exist in podLister, aborted adding it to the nominator", "pod", klog.KObj(pi.Pod))
+			return
+		}
+		if updatedPod.Spec.NodeName != "" {
+			logger.V(4).Info("Pod is already scheduled to a node, aborted adding it to the nominator", "pod", klog.KObj(pi.Pod), "node", updatedPod.Spec.NodeName)
+			return
+		}
+	}
+
+	npm.nominatedPodToNode[pi.Pod.UID] = nodeName
+	for _, np := range npm.nominatedPods[nodeName] {
+		if np.uid == pi.Pod.UID {
+			logger.V(4).Info("Pod already exists in the nominator", "pod", np.uid)
+			return
+		}
+	}
+	npm.nominatedPods[nodeName] = append(npm.nominatedPods[nodeName], podToRef(pi.Pod))
+}
+
+// UpdateNominatedPod updates the <oldPod> with <newPod>.
+func (npm *nominator) UpdateNominatedPod(logger klog.Logger, oldPod *v1.Pod, newPodInfo *framework.PodInfo) {
+	npm.nLock.Lock()
+	defer npm.nLock.Unlock()
+	// In some cases, an Update event with no "NominatedNode" present is received right
+	// after a node("NominatedNode") is reserved for this pod in memory.
+	// In this case, we need to keep reserving the NominatedNode when updating the pod pointer.
+	var nominatingInfo *framework.NominatingInfo
+	// We won't fall into below `if` block if the Update event represents:
+	// (1) NominatedNode info is added
+	// (2) NominatedNode info is updated
+	// (3) NominatedNode info is removed
+	if nominatedNodeName(oldPod) == "" && nominatedNodeName(newPodInfo.Pod) == "" {
+		if nnn, ok := npm.nominatedPodToNode[oldPod.UID]; ok {
+			// This is the only case we should continue reserving the NominatedNode
+			nominatingInfo = &framework.NominatingInfo{
+				NominatingMode:    framework.ModeOverride,
+				NominatedNodeName: nnn,
+			}
+		}
+	}
+	// We update irrespective of the nominatedNodeName changed or not, to ensure
+	// that pod pointer is updated.
+	npm.deleteUnlocked(oldPod)
+	npm.addNominatedPodUnlocked(logger, newPodInfo, nominatingInfo)
+}
+
+// DeleteNominatedPodIfExists deletes <pod> from nominatedPods.
+func (npm *nominator) DeleteNominatedPodIfExists(pod *v1.Pod) {
+	npm.nLock.Lock()
+	npm.deleteUnlocked(pod)
+	npm.nLock.Unlock()
+}
+
+func (npm *nominator) deleteUnlocked(p *v1.Pod) {
+	nnn, ok := npm.nominatedPodToNode[p.UID]
+	if !ok {
+		return
+	}
+	for i, np := range npm.nominatedPods[nnn] {
+		if np.uid == p.UID {
+			npm.nominatedPods[nnn] = append(npm.nominatedPods[nnn][:i], npm.nominatedPods[nnn][i+1:]...)
+			if len(npm.nominatedPods[nnn]) == 0 {
+				delete(npm.nominatedPods, nnn)
+			}
+			break
+		}
+	}
+	delete(npm.nominatedPodToNode, p.UID)
+}
+
+func (npm *nominator) nominatedPodsForNode(nodeName string) []podRef {
+	npm.nLock.RLock()
+	defer npm.nLock.RUnlock()
+	return slices.Clone(npm.nominatedPods[nodeName])
+}
+
+// nominatedNodeName returns nominated node name of a Pod.
+func nominatedNodeName(pod *v1.Pod) string {
+	return pod.Status.NominatedNodeName
+}
+
+type podRef struct {
+	name      string
+	namespace string
+	uid       types.UID
+}
+
+func podToRef(pod *v1.Pod) podRef {
+	return podRef{
+		name:      pod.Name,
+		namespace: pod.Namespace,
+		uid:       pod.UID,
+	}
+}
+
+func (np podRef) toPod() *v1.Pod {
+	return &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      np.name,
+			Namespace: np.namespace,
+			UID:       np.uid,
+		},
+	}
+}

vendor/k8s.io/kubernetes/pkg/scheduler/backend/queue/testing.go

@@ -0,0 +1,63 @@
+/*
+Copyright 2021 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package queue
+
+import (
+	"context"
+	"time"
+
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/informers"
+	"k8s.io/client-go/kubernetes/fake"
+	"k8s.io/kubernetes/pkg/scheduler/framework"
+	"k8s.io/kubernetes/pkg/scheduler/metrics"
+)
+
+// NewTestQueue creates a priority queue with an empty informer factory.
+func NewTestQueue(ctx context.Context, lessFn framework.LessFunc, opts ...Option) *PriorityQueue {
+	return NewTestQueueWithObjects(ctx, lessFn, nil, opts...)
+}
+
+// NewTestQueueWithObjects creates a priority queue with an informer factory
+// populated with the provided objects.
+func NewTestQueueWithObjects(
+	ctx context.Context,
+	lessFn framework.LessFunc,
+	objs []runtime.Object,
+	opts ...Option,
+) *PriorityQueue {
+	informerFactory := informers.NewSharedInformerFactory(fake.NewClientset(objs...), 0)
+
+	// Because some major functions (e.g., Pop) requires the metric recorder to be set,
+	// we always set a metric recorder here.
+	recorder := metrics.NewMetricsAsyncRecorder(10, 20*time.Microsecond, ctx.Done())
+	// We set it before the options that users provide, so that users can override it.
+	opts = append([]Option{WithMetricsRecorder(*recorder)}, opts...)
+	return NewTestQueueWithInformerFactory(ctx, lessFn, informerFactory, opts...)
+}
+
+func NewTestQueueWithInformerFactory(
+	ctx context.Context,
+	lessFn framework.LessFunc,
+	informerFactory informers.SharedInformerFactory,
+	opts ...Option,
+) *PriorityQueue {
+	pq := NewPriorityQueue(lessFn, informerFactory, opts...)
+	informerFactory.Start(ctx.Done())
+	informerFactory.WaitForCacheSync(ctx.Done())
+	return pq
+}