From 382a2aa3f63ef07b7a6dfac636a344977ebfc1e6 Mon Sep 17 00:00:00 2001
From: Stefano Avallone <stavallo@unina.it>
Date: Wed, 1 Sep 2021 13:49:17 +0200
Subject: [PATCH] wifi: Trace dropped QoS old packets

---
 src/wifi/model/block-ack-manager.cc | 14 ++++++++++++++
 src/wifi/model/block-ack-manager.h  | 10 ++++++++++
 src/wifi/model/qos-txop.cc          |  5 +++++
 src/wifi/model/wifi-mac.h           |  3 ++-
 4 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/wifi/model/block-ack-manager.cc b/src/wifi/model/block-ack-manager.cc
index aa0673f6c..7f38664ac 100644
--- a/src/wifi/model/block-ack-manager.cc
+++ b/src/wifi/model/block-ack-manager.cc
@@ -401,6 +401,10 @@ BlockAckManager::HandleInFlightMpdu (PacketQueueI mpduIt, MpduStatus status,
   if (it->second.first.GetDistance (hdr.GetSequenceNumber ()) >= SEQNO_SPACE_HALF_SIZE)
     {
       NS_LOG_DEBUG ("Old packet. Remove from the EDCA queue, too");
+      if (!m_droppedOldMpduCallback.IsNull ())
+        {
+          m_droppedOldMpduCallback (*queueIt);
+        }
       queue->Remove (queueIt);
       return it->second.second.erase (mpduIt);
     }
@@ -607,6 +611,10 @@ BlockAckManager::NotifyDiscardedMpdu (Ptr<const WifiMacQueueItem> mpdu)
       if (it->second.first.GetDistance ((*mpduIt)->GetHeader ().GetSequenceNumber ()) >= SEQNO_SPACE_HALF_SIZE)
         {
           m_queue->DequeueIfQueued (*mpduIt);
+          if (!m_droppedOldMpduCallback.IsNull ())
+            {
+              m_droppedOldMpduCallback (*mpduIt);
+            }
           mpduIt = it->second.second.erase (mpduIt);
         }
       else
@@ -843,6 +851,12 @@ BlockAckManager::SetTxFailedCallback (TxFailed callback)
   m_txFailedCallback = callback;
 }
 
+void
+BlockAckManager::SetDroppedOldMpduCallback (DroppedOldMpdu callback)
+{
+  m_droppedOldMpduCallback = callback;
+}
+
 uint16_t
 BlockAckManager::GetRecipientBufferSize (Mac48Address recipient, uint8_t tid) const
 {
diff --git a/src/wifi/model/block-ack-manager.h b/src/wifi/model/block-ack-manager.h
index 2a377c341..421c0ab91 100644
--- a/src/wifi/model/block-ack-manager.h
+++ b/src/wifi/model/block-ack-manager.h
@@ -356,6 +356,11 @@ public:
    * typedef for a callback to invoke when an MPDU is negatively ack'ed.
    */
   typedef Callback <void, Ptr<const WifiMacQueueItem>> TxFailed;
+  /**
+   * typedef for a callback to invoke when an MPDU is dropped.
+   */
+  typedef Callback <void, Ptr<const WifiMacQueueItem>> DroppedOldMpdu;
+
   /**
    * \param callback the callback to invoke when a
    * packet transmission was completed successfully.
@@ -366,6 +371,10 @@ public:
    * packet transmission was completed unsuccessfully.
    */
   void SetTxFailedCallback (TxFailed callback);
+  /**
+   * \param callback the callback to invoke when an old MPDU is dropped
+   */
+  void SetDroppedOldMpduCallback (DroppedOldMpdu callback);
 
   /**
    * TracedCallback signature for state changes.
@@ -483,6 +492,7 @@ private:
   Callback<void, Mac48Address, uint8_t> m_unblockPackets; ///< unblock packets callback
   TxOk m_txOkCallback;                                    ///< transmit OK callback
   TxFailed m_txFailedCallback;                            ///< transmit failed callback
+  DroppedOldMpdu m_droppedOldMpduCallback;                ///< the dropped MPDU callback
 
   /**
    * The trace source fired when a state transition occurred.
diff --git a/src/wifi/model/qos-txop.cc b/src/wifi/model/qos-txop.cc
index 09eb6be23..34bc7598f 100644
--- a/src/wifi/model/qos-txop.cc
+++ b/src/wifi/model/qos-txop.cc
@@ -149,6 +149,7 @@ QosTxop::SetDroppedMpduCallback (DroppedMpdu callback)
 {
   NS_LOG_FUNCTION (this << &callback);
   Txop::SetDroppedMpduCallback (callback);
+  m_baManager->SetDroppedOldMpduCallback (callback.Bind (WIFI_MAC_DROP_QOS_OLD_PACKET));
 }
 
 void
@@ -390,6 +391,10 @@ QosTxop::PeekNextMpdu (WifiMacQueueItem::QueueIteratorPair queueIt, uint8_t tid,
           && IsQosOldPacket (*queueIt.it))
         {
           NS_LOG_DEBUG ("Removing an old packet from EDCA queue: " << **queueIt.it);
+          if (!m_droppedMpduCallback.IsNull ())
+            {
+              m_droppedMpduCallback (WIFI_MAC_DROP_QOS_OLD_PACKET, *queueIt.it);
+            }
           queueIt.it = m_queue->Remove (queueIt.it);
           queueIt.it = peek ();
         }
diff --git a/src/wifi/model/wifi-mac.h b/src/wifi/model/wifi-mac.h
index 9fb6d389c..9f914a50d 100644
--- a/src/wifi/model/wifi-mac.h
+++ b/src/wifi/model/wifi-mac.h
@@ -55,7 +55,8 @@ enum WifiMacDropReason : uint8_t
 {
   WIFI_MAC_DROP_FAILED_ENQUEUE = 0,
   WIFI_MAC_DROP_EXPIRED_LIFETIME,
-  WIFI_MAC_DROP_REACHED_RETRY_LIMIT
+  WIFI_MAC_DROP_REACHED_RETRY_LIMIT,
+  WIFI_MAC_DROP_QOS_OLD_PACKET
 };
 
 /**