diff --git a/src/sf_nio.c b/src/sf_nio.c
index 85f3599..b5fc9b6 100644
--- a/src/sf_nio.c
+++ b/src/sf_nio.c
@@ -324,11 +324,18 @@ int sf_nio_notify(struct fast_task_info *task, const int stage)
     if (!__sync_bool_compare_and_swap(&task->nio_stages.notify,
                 SF_NIO_STAGE_NONE, stage))
     {
-        logWarning("file: "__FILE__", line: %d, "
-                "current stage: %d != %d, skip set stage to %d",
-                __LINE__, __sync_fetch_and_sub(&task->nio_stages.notify, 0),
-                SF_NIO_STAGE_NONE, stage);
-        return EAGAIN;
+        if (__sync_fetch_and_add(&task->nio_stages.notify, 0) == stage) {
+            logDebug("file: "__FILE__", line: %d, "
+                    "current stage: %d equals to the target, skip set",
+                    __LINE__, stage);
+            return 0;
+        } else {
+            logWarning("file: "__FILE__", line: %d, "
+                    "current stage: %d != %d, skip set stage to %d",
+                    __LINE__, __sync_fetch_and_add(&task->nio_stages.notify, 0),
+                    SF_NIO_STAGE_NONE, stage);
+            return EAGAIN;
+        }
     }
 
     PTHREAD_MUTEX_LOCK(&task->thread_data->waiting_queue.lock);