wifi: Add a frame retry count for each MSDU, A-MSDU, MMPDU

src/wifi/model/wifi-mpdu.cc

@@ -29,6 +29,7 @@ WifiMpdu::WifiMpdu(Ptr<const Packet> p, const WifiMacHeader& header, Time stamp)
     auto& original = std::get<OriginalInfo>(m_instanceInfo);
     original.m_packet = p;
     original.m_timestamp = stamp;
+    original.m_retryCount = 0;
 
     if (header.IsQosData() && header.IsQosAmsdu())
     {
@@ -113,6 +114,41 @@ WifiMpdu::GetTimestamp() const
     return std::get<OriginalInfo>(origInstanceInfo).m_timestamp;
 }
 
+uint32_t
+WifiMpdu::GetRetryCount() const
+{
+    if (auto original = std::get_if<ORIGINAL>(&m_instanceInfo))
+    {
+        return original->m_retryCount;
+    }
+    const auto& origInstanceInfo = std::get<Ptr<WifiMpdu>>(m_instanceInfo)->m_instanceInfo;
+    return std::get<OriginalInfo>(origInstanceInfo).m_retryCount;
+}
+
+void
+WifiMpdu::IncrementRetryCount()
+{
+    NS_LOG_FUNCTION(this);
+
+    if (m_header.IsBlockAckReq() || m_header.IsTrigger())
+    {
+        // this function may be called for these frames, but a retry count must not be maintained
+        // for them
+        return;
+    }
+
+    NS_ABORT_MSG_UNLESS(m_header.IsData() || m_header.IsMgt(),
+                        "Frame retry count is not maintained for frames of type "
+                            << m_header.GetTypeString());
+    if (auto original = std::get_if<ORIGINAL>(&m_instanceInfo))
+    {
+        ++original->m_retryCount;
+        return;
+    }
+    auto& origInstanceInfo = std::get<Ptr<WifiMpdu>>(m_instanceInfo)->m_instanceInfo;
+    ++std::get<OriginalInfo>(origInstanceInfo).m_retryCount;
+}
+
 const WifiMacHeader&
 WifiMpdu::GetHeader() const
 {
@@ -181,6 +217,7 @@ WifiMpdu::Aggregate(Ptr<const WifiMpdu> msdu)
         // An MSDU is going to be aggregated to this MPDU, hence this has to be an A-MSDU now
         Ptr<const WifiMpdu> firstMsdu = Create<const WifiMpdu>(*this);
         original.m_packet = Create<Packet>();
+        original.m_retryCount = 0;
         DoAggregate(firstMsdu);
 
         m_header.SetQosAmsdu();
@@ -370,7 +407,8 @@ WifiMpdu::end() const
 void
 WifiMpdu::Print(std::ostream& os) const
 {
-    os << m_header << ", payloadSize=" << GetPacketSize() << ", queued=" << IsQueued();
+    os << m_header << ", payloadSize=" << GetPacketSize() << ", retryCount=" << GetRetryCount()
+       << ", queued=" << IsQueued();
     if (IsQueued())
     {
         os << ", residualLifetime=" << (GetExpiryTime() - Simulator::Now()).As(Time::US)

src/wifi/model/wifi-mpdu.h

@@ -184,6 +184,16 @@ class WifiMpdu : public SimpleRefCount<WifiMpdu>
      */
     Time GetExpiryTime() const;
 
+    /**
+     * @return the frame retry count
+     */
+    uint32_t GetRetryCount() const;
+
+    /**
+     * Increment the frame retry count.
+     */
+    void IncrementRetryCount();
+
     /**
      * @brief Get the MAC protocol data unit (MPDU) corresponding to this item
      *        (i.e. a copy of the packet stored in this item wrapped with MAC
@@ -279,6 +289,7 @@ class WifiMpdu : public SimpleRefCount<WifiMpdu>
         DeaggregatedMsdus m_msduList;      //!< list of aggregated MSDUs included in this MPDU
         std::optional<Iterator> m_queueIt; //!< Queue iterator pointing to this MPDU, if queued
         bool m_seqNoAssigned;              //!< whether a sequence number has been assigned
+        uint32_t m_retryCount; //!< the frame retry count maintained for each MSDU, A-MSDU or MMPDU
     };
 
     /**

src/wifi/model/wifi-psdu.cc

@@ -163,6 +163,16 @@ WifiPsdu::SetDuration(Time duration)
     }
 }
 
+void
+WifiPsdu::IncrementRetryCount()
+{
+    NS_LOG_FUNCTION(this);
+    for (auto& mpdu : m_mpduList)
+    {
+        mpdu->IncrementRetryCount();
+    }
+}
+
 std::set<uint8_t>
 WifiPsdu::GetTids() const
 {

src/wifi/model/wifi-psdu.h

@@ -150,6 +150,11 @@ class WifiPsdu : public SimpleRefCount<WifiPsdu>
      */
     void SetDuration(Time duration);
 
+    /**
+     * Increment the frame retry count for all the MPDUs.
+     */
+    void IncrementRetryCount();
+
     /**
      * Get the set of TIDs of the QoS Data frames included in the PSDU. Note that
      * only single-TID A-MPDUs are currently supported, hence the returned set