Rlc: converting LteRlcPduNewData chunk to tag

As it is not real packet data, just a simulation artifact for
communication between protocol layers (RLC->MAC notification)

No fingerprint change!

Author: avarga

src/simu5g/stack/mac/LteMacEnb.cc

@@ -33,6 +33,7 @@
 #include "simu5g/stack/phy/LtePhyBase.h"
 #include "simu5g/stack/rlc/packet/LteRlcPdu_m.h"
 #include "simu5g/stack/rlc/packet/LteRlcPdu_m.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 #include "simu5g/stack/packetFlowManager/PacketFlowManagerBase.h"
 #include "simu5g/stack/rlc/um/LteRlcUm.h"
 #include "simu5g/stack/pdcp/NrPdcpEnb.h"
@@ -672,10 +673,11 @@ bool LteMacEnb::bufferizePacket(cPacket *cpkt)
     LteMacBuffer *vqueue = connInfo.buffer;
 
     // this packet is used to signal the arrival of new data in the RLC buffers
-    if (checkIfHeaderType<LteRlcPduNewData>(pkt)) {
+    if (pkt->findTag<LteRlcNewDataTag>()) {
         // update the virtual buffer for this connection
         // build the virtual packet corresponding to this incoming packet
-        pkt->popAtFront<LteRlcPduNewData>();
+        // remove the tag since it's just a notification
+        pkt->removeTag<LteRlcNewDataTag>();
         auto rlcSdu = pkt->peekAtFront<LteRlcSdu>();
         PacketInfo vpkt(rlcSdu->getLengthMainPacket(), pkt->getTimestamp());
         vqueue->pushBack(vpkt);
@@ -719,7 +721,7 @@ void LteMacEnb::handleUpperMessage(cPacket *pktAux)
     auto lteInfo = pkt->getTag<FlowControlInfo>();
     MacCid cid = MacCid(lteInfo->getDestId(), lteInfo->getLcid());
 
-    bool isLteRlcPduNewData = checkIfHeaderType<LteRlcPduNewData>(pkt);
+    bool isLteRlcPduNewData = (pkt->findTag<LteRlcNewDataTag>() != nullptr);
 
     bool packetIsBuffered = bufferizePacket(pkt);  // will buffer (or destroy if the queue is full)
 

src/simu5g/stack/mac/LteMacUe.cc

@@ -23,6 +23,7 @@
 #include "simu5g/stack/mac/scheduler/LteSchedulerUeUl.h"
 #include "simu5g/stack/rlc/packet/LteRlcPdu_m.h"
 #include "simu5g/stack/rlc/packet/LteRlcSdu_m.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 
 namespace simu5g {
 
@@ -266,10 +267,11 @@ bool LteMacUe::bufferizePacket(cPacket *cpkt)
     LteMacBuffer *vqueue = connInfo.buffer;
 
     // this packet is used to signal the arrival of new data in the RLC buffers
-    if (checkIfHeaderType<LteRlcPduNewData>(pkt)) {
+    if (pkt->findTag<LteRlcNewDataTag>()) {
+        // remove the tag since it's just a notification
+        pkt->removeTag<LteRlcNewDataTag>();
         // update the virtual buffer for this connection
         // build the virtual packet corresponding to this incoming packet
-        pkt->popAtFront<LteRlcPduNewData>();
         auto rlcSdu = pkt->peekAtFront<LteRlcSdu>();
         PacketInfo vpkt(rlcSdu->getLengthMainPacket(), pkt->getTimestamp());
         vqueue->pushBack(vpkt);
@@ -564,7 +566,7 @@ void LteMacUe::macPduUnmake(cPacket *cpkt)
 void LteMacUe::handleUpperMessage(cPacket *pktAux)
 {
     auto pkt = check_and_cast<Packet *>(pktAux);
-    bool isLteRlcPduNewDataInd = checkIfHeaderType<LteRlcPduNewData>(pkt);
+    bool isLteRlcPduNewDataInd = (pkt->findTag<LteRlcNewDataTag>() != nullptr);
 
     // bufferize packet
     bufferizePacket(pkt);

src/simu5g/stack/rlc/am/LteRlcAm.cc

@@ -16,6 +16,7 @@
 #include "simu5g/stack/rlc/am/AmTxQueue.h"
 #include "simu5g/stack/rlc/am/AmRxQueue.h"
 #include "simu5g/stack/mac/packet/LteMacSduRequest.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 
 namespace simu5g {
 
@@ -232,8 +233,8 @@ void LteRlcAm::indicateNewDataToMac(cPacket *pktAux) {
 
     newData->insertAtFront(rlcSdu);
 
-    auto newDataHdr = inet::makeShared<LteRlcPduNewData>();
-    newData->insertAtFront(newDataHdr);
+    // add tag to indicate new data availability to MAC
+    newData->addTag<LteRlcNewDataTag>();
 
     newData->copyTags(*pkt);
 

src/simu5g/stack/rlc/packet/LteRlcNewDataTag.msg

@@ -0,0 +1,29 @@
+//
+//                  Simu5G
+//
+// Authors: Giovanni Nardini, Giovanni Stea, Antonio Virdis (University of Pisa)
+//
+// This file is part of a software released under the license included in file
+// "license.pdf". Please read LICENSE and README files before using it.
+// The above files and the present reference are part of the software itself,
+// and cannot be removed from it.
+//
+
+import inet.common.INETDefs;
+import inet.common.TagBase;
+
+namespace simu5g;
+
+//
+// @class LteRlcNewDataTag
+// @brief Tag to indicate new data availability to MAC layer
+//
+// This tag replaces LteRlcPduNewData chunk and serves as a notification
+// mechanism to inform the MAC layer that new data is available in the
+// RLC transmission buffers. It carries no data fields - its mere presence
+// on a packet indicates new data availability.
+//
+class LteRlcNewDataTag extends inet::TagBase
+{
+    // No fields needed - this is purely a notification tag
+}

src/simu5g/stack/rlc/packet/LteRlcPdu.msg

@@ -27,12 +27,6 @@ class size_t {
 
 namespace simu5g;
 
-// new data indication for MAC
-class LteRlcPduNewData extends inet::FieldsChunk
-{
-    chunkLength = inet::B(0);
-}
-
 class LteRlcDataPdu extends inet::FieldsChunk
 {
     chunkLength = inet::b(1);

src/simu5g/stack/rlc/tm/LteRlcTm.cc

@@ -15,6 +15,7 @@
 #include "simu5g/stack/rlc/packet/LteRlcPdu_m.h"
 #include "simu5g/stack/rlc/packet/LteRlcSdu_m.h"
 #include "simu5g/stack/mac/packet/LteMacSduRequest.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 
 namespace simu5g {
 
@@ -65,13 +66,13 @@ void LteRlcTm::handleUpperMessage(cPacket *pktAux)
     emit(signal, 0.0);
 
     // create a message to notify the MAC layer that the queue contains new data
-    auto newDataPkt = inet::makeShared<LteRlcPduNewData>();
     // make a copy of the RLC SDU
     // the MAC will only be interested in the size of this packet
     auto pktDup = pkt->dup();
-    pktDup->insertAtFront(newDataPkt);
+    // add tag to indicate new data availability to MAC
+    pktDup->addTag<LteRlcNewDataTag>();
 
-    EV << "LteRlcTm::handleUpperMessage - Sending message " << newDataPkt->getName() << " to port TM_Sap_down$o\n";
+    EV << "LteRlcTm::handleUpperMessage - Sending new data indication to port TM_Sap_down$o\n";
     emit(sentPacketToLowerLayerSignal_, pktDup);
     send(pktDup, downOutGate_);
 }
@@ -139,4 +140,3 @@ void LteRlcTm::handleMessage(cMessage *msg)
 }
 
 } //namespace
-

src/simu5g/stack/rlc/um/LteRlcUm.cc

@@ -14,6 +14,7 @@
 
 #include "simu5g/stack/rlc/um/LteRlcUm.h"
 #include "simu5g/stack/mac/packet/LteMacSduRequest.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 
 namespace simu5g {
 
@@ -131,13 +132,13 @@ void LteRlcUm::handleUpperMessage(cPacket *pktAux)
             EV << "LteRlcUm::handleUpperMessage - Enqueue packet " << rlcPkt->getClassName() << " into the Tx Buffer\n";
 
             // create a message to notify the MAC layer that the queue contains new data
-            auto newDataPkt = inet::makeShared<LteRlcPduNewData>();
             // make a copy of the RLC SDU
             auto pktDup = pkt->dup();
-            pktDup->insertAtFront(newDataPkt);
+            // add tag to indicate new data availability to MAC
+            pktDup->addTag<LteRlcNewDataTag>();
             // the MAC will only be interested in the size of this packet
 
-            EV << "LteRlcUm::handleUpperMessage - Sending message " << newDataPkt->getClassName() << " to port UM_Sap_down$o\n";
+            EV << "LteRlcUm::handleUpperMessage - Sending new data indication to port UM_Sap_down$o\n";
             send(pktDup, downOutGate_);
         }
         else {

src/simu5g/stack/rlc/um/UmTxEntity.cc

@@ -11,6 +11,7 @@
 
 #include "simu5g/stack/rlc/um/UmTxEntity.h"
 #include "simu5g/stack/rlc/packet/LteRlcPdu_m.h"
+#include "simu5g/stack/rlc/packet/LteRlcNewDataTag_m.h"
 
 #include "simu5g/stack/packetFlowManager/PacketFlowManagerUe.h"
 #include "simu5g/stack/packetFlowManager/PacketFlowManagerEnb.h"
@@ -321,10 +322,10 @@ void UmTxEntity::resumeDownstreamInPackets()
         // store the SDU in the TX buffer
         if (enque(pktRlc)) {
             // create a message to notify the MAC layer that the queue contains new data
-            auto newDataPkt = inet::makeShared<LteRlcPduNewData>();
             // make a copy of the RLC SDU
             auto pktRlcdup = pktRlc->dup();
-            pktRlcdup->insertAtFront(newDataPkt);
+            // add tag to indicate new data availability to MAC
+            pktRlcdup->addTag<LteRlcNewDataTag>();
             // send the new data indication to the MAC
             lteRlc_->sendToLowerLayer(pktRlcdup);
         }
@@ -373,4 +374,3 @@ void UmTxEntity::rlcHandleD2DModeSwitch(bool oldConnection, bool clearBuffer)
 }
 
 } //namespace
-