From e4e962c31530e055ca9e34a17337b76f67ef2e9e Mon Sep 17 00:00:00 2001
From: Stefano Avallone <stavallo@unina.it>
Date: Mon, 13 Feb 2023 15:25:46 +0100
Subject: [PATCH] wifi: Always update queue priority when enqueuing an MPDU

---
 src/wifi/model/fcfs-wifi-queue-scheduler.cc | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/src/wifi/model/fcfs-wifi-queue-scheduler.cc b/src/wifi/model/fcfs-wifi-queue-scheduler.cc
index 825c5b3e9..ef255f430 100644
--- a/src/wifi/model/fcfs-wifi-queue-scheduler.cc
+++ b/src/wifi/model/fcfs-wifi-queue-scheduler.cc
@@ -132,15 +132,11 @@ FcfsWifiQueueScheduler::DoNotifyEnqueue(AcIndex ac, Ptr<WifiMpdu> mpdu)
 
     const auto queueId = WifiMacQueueContainer::GetQueueId(mpdu);
 
-    if (GetWifiMacQueue(ac)->GetNPackets(queueId) > 1)
-    {
-        // Enqueue takes place at the tail, while the priority is determined by the
-        // head of the queue. Therefore, if the queue was not empty before inserting
-        // this MPDU, priority does not change
-        return;
-    }
+    // priority is determined by the head of the queue
+    auto item = GetWifiMacQueue(ac)->PeekByQueueId(queueId);
+    NS_ASSERT(item);
 
-    SetPriority(ac, queueId, {mpdu->GetTimestamp(), std::get<WifiContainerQueueType>(queueId)});
+    SetPriority(ac, queueId, {item->GetTimestamp(), std::get<WifiContainerQueueType>(queueId)});
 }
 
 void