Use read lock for PendingPods

pkg/scheduler/internal/queue/scheduling_queue.go

@@ -702,8 +702,8 @@ func (p *PriorityQueue) NominatedPodsForNode(nodeName string) []*v1.Pod {
 // PendingPods returns all the pending pods in the queue. This function is
 // used for debugging purposes in the scheduler cache dumper and comparer.
 func (p *PriorityQueue) PendingPods() []*v1.Pod {
-	p.lock.Lock()
-	defer p.lock.Unlock()
+	p.lock.RLock()
+	defer p.lock.RUnlock()
 	result := []*v1.Pod{}
 	for _, pInfo := range p.activeQ.List() {
 		result = append(result, pInfo.(*podInfo).pod)