From 7fef56b479482d17579ad712361a44b8310160d3 Mon Sep 17 00:00:00 2001
From: Yang Liming <liming.yang@139.com>
Date: Tue, 20 Aug 2024 19:37:01 +0800
Subject: [PATCH] fix mpsc queue cur enqueue node to atomic exhange

---
 src/butil/containers/mpsc_queue.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/butil/containers/mpsc_queue.h b/src/butil/containers/mpsc_queue.h
index f9e1d78099..6db50f285c 100644
--- a/src/butil/containers/mpsc_queue.h
+++ b/src/butil/containers/mpsc_queue.h
@@ -129,13 +129,12 @@ bool MPSCQueue<T, Alloc>::DequeueImpl(T* data) {
     if (_cur_dequeue_node) {
         node = _cur_dequeue_node;
     } else {
-        node = _cur_enqueue_node.load(memory_order_relaxed);
+        node = _cur_enqueue_node.exchange(NULL, memory_order_relaxed);
     }
     if (!node) {
         return false;
     }
 
-    _cur_enqueue_node.store(NULL, memory_order_relaxed);
     if (data) {
         auto mem = (T* const)node->data_mem;
         *data = std::move(*mem);