tasklist: fix consumer deadlock

task/list.go

@@ -187,7 +187,6 @@ func (list *List) GetTaskReturnValueByID(ID int) (*ProcessReturnValue, error) {
 // become available.
 func (list *List) RunTaskInBackground(name string, resources []string, process Process) (Task, *ResourceConflictError) {
 	list.Lock()
-	defer list.Unlock()
 
 	list.idCounter++
 	wgTask := &sync.WaitGroup{}
@@ -204,7 +203,11 @@ func (list *List) RunTaskInBackground(name string, resources []string, process P
 	tasks := list.usedResources.UsedBy(resources)
 	if len(tasks) == 0 {
 		list.usedResources.MarkInUse(task.resources, task)
+		// queueing task might block if channel not ready, unlock list before queueing
+		list.Unlock()
 		list.queue <- task
+	} else {
+		list.Unlock()
 	}
 
 	return *task, nil