diff --git a/HISTORY b/HISTORY
index b699faa..643a404 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,6 +1,7 @@
 
 Version 1.52  2021-06-01
   * process_stop more gracefully (kill -9 on timeout)
+  * add function fc_queue_pop_to_queue_ex
 
 Version 1.51  2021-05-27
   * fast_mblock.[hc]: support batch alloc and batch free
diff --git a/src/fc_queue.c b/src/fc_queue.c
index 8c4c892..784f6ab 100644
--- a/src/fc_queue.c
+++ b/src/fc_queue.c
@@ -155,10 +155,16 @@ void fc_queue_push_queue_to_tail_ex(struct fc_queue *queue,
     PTHREAD_MUTEX_UNLOCK(&queue->lc_pair.lock);
 }
 
-void fc_queue_pop_to_queue(struct fc_queue *queue,
-        struct fc_queue_info *qinfo)
+void fc_queue_pop_to_queue_ex(struct fc_queue *queue,
+        struct fc_queue_info *qinfo, const bool blocked)
 {
     PTHREAD_MUTEX_LOCK(&queue->lc_pair.lock);
+    if (queue->head == NULL) {
+        if (blocked) {
+            pthread_cond_wait(&queue->lc_pair.cond, &queue->lc_pair.lock);
+        }
+    }
+
     if (queue->head != NULL) {
         qinfo->head = queue->head;
         qinfo->tail = queue->tail;
diff --git a/src/fc_queue.h b/src/fc_queue.h
index 3be5e7e..0df3675 100644
--- a/src/fc_queue.h
+++ b/src/fc_queue.h
@@ -129,8 +129,14 @@ void *fc_queue_pop_all_ex(struct fc_queue *queue, const bool blocked);
 #define fc_queue_pop_all(queue) fc_queue_pop_all_ex(queue, true)
 #define fc_queue_try_pop_all(queue) fc_queue_pop_all_ex(queue, false)
 
-void fc_queue_pop_to_queue(struct fc_queue *queue,
-        struct fc_queue_info *qinfo);
+void fc_queue_pop_to_queue_ex(struct fc_queue *queue,
+        struct fc_queue_info *qinfo, const bool blocked);
+
+#define fc_queue_pop_to_queue(queue, qinfo) \
+    fc_queue_pop_to_queue_ex(queue, qinfo, true)
+
+#define fc_queue_try_pop_to_queue(queue, qinfo) \
+    fc_queue_pop_to_queue_ex(queue, qinfo, false)
 
 static inline bool fc_queue_empty(struct fc_queue *queue)
 {
diff --git a/src/sched_thread.c b/src/sched_thread.c
index cfd291e..60f2e30 100644
--- a/src/sched_thread.c
+++ b/src/sched_thread.c
@@ -840,7 +840,7 @@ static void sched_deal_task_queue(ScheduleContext *pContext)
     FastDelayTask *task;
     struct fc_queue_info qinfo;
 
-    fc_queue_pop_to_queue(&pContext->delay_queue, &qinfo);
+    fc_queue_try_pop_to_queue(&pContext->delay_queue, &qinfo);
     task = qinfo.head;
     while (task != NULL)
     {