From c93ec896649edc6bc62e8a10d76eefe38d94d628 Mon Sep 17 00:00:00 2001
From: BAILLEUL Quentin <quentin.bailleul@irt-saintexupery.com>
Date: Tue, 2 Dec 2025 11:43:04 +0100
Subject: [PATCH] Fix issue with CBS

---
 contrib/tsn/model/cbs.cc                      | 25 +++++++++++++++----
 contrib/tsn/model/cbs.h                       |  1 +
 contrib/tsn/model/tsn-net-device.cc           |  6 +++++
 .../model/tsn-transmission-selection-algo.cc  |  7 +++++-
 .../model/tsn-transmission-selection-algo.h   |  2 +-
 5 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/contrib/tsn/model/cbs.cc b/contrib/tsn/model/cbs.cc
index e9b59a8..cb0593d 100644
--- a/contrib/tsn/model/cbs.cc
+++ b/contrib/tsn/model/cbs.cc
@@ -64,9 +64,6 @@ Cbs::IsReadyToTransmit()
 {
   NS_LOG_FUNCTION(this);
   if(m_credit>=0){
-    if (m_state==WAITING){
-      UpdateCredit(false);
-    }
     return true;
   }
   else{
@@ -75,6 +72,26 @@ Cbs::IsReadyToTransmit()
   }
 }
 
+void
+Cbs::Update()
+{
+  NS_LOG_FUNCTION(this);
+  if (m_state != TRANSMITTING)
+  {
+    if (m_queue->IsEmpty())
+    {
+      m_state = IDLE;
+    }
+    else
+    {
+      m_state = WAITING;
+    }
+  }
+  UpdateCredit(false);
+}
+
+
+
 void
 Cbs::UpdateCredit(bool trigger_cb)
 {
@@ -82,8 +99,6 @@ Cbs::UpdateCredit(bool trigger_cb)
   NS_ASSERT_MSG(m_idleSlope < m_maxIdleSlope, "Trying to use an idleSlope higher than " << m_maxIdleSlope << ".");
 
   Time sinceLastCreditUpdate = Simulator::Now() - m_lastUpdateCreditTime;
-  NS_LOG_INFO(sinceLastCreditUpdate);
-  NS_LOG_INFO("State = " << m_state);
   if(m_transmissionGateIsOpen){
     if(m_state == WAITING)
     {
diff --git a/contrib/tsn/model/cbs.h b/contrib/tsn/model/cbs.h
index 9fa1567..130e7bc 100644
--- a/contrib/tsn/model/cbs.h
+++ b/contrib/tsn/model/cbs.h
@@ -40,6 +40,7 @@ class Cbs: public TsnTransmissionSelectionAlgo
     void TransmitStart(Ptr<Packet> p, Time txTime) override;
     void TransmitComplete(Ptr<Packet> p) override;
     void UpdateTransmissionGate(bool IsOpen) override;
+    void Update() override;
 
 
     TracedCallback<double> m_creditTrace;
diff --git a/contrib/tsn/model/tsn-net-device.cc b/contrib/tsn/model/tsn-net-device.cc
index edce80b..4369ea2 100644
--- a/contrib/tsn/model/tsn-net-device.cc
+++ b/contrib/tsn/model/tsn-net-device.cc
@@ -111,6 +111,12 @@ int
 TsnNetDevice::TransmitSelection()
 {
   NS_LOG_FUNCTION(this);
+  //Udpate Transmission selection algo states (e.g update cbs credit)
+  for (int i = m_queues.size(); i --> 0; )
+  {
+    m_transmissionSelectionAlgos[i]->Update();
+  }
+
   for (int i = m_queues.size(); i --> 0; )
   {
       if(!m_queues[i]->IsEmpty() && m_tas->IsGateOpen(i))
diff --git a/contrib/tsn/model/tsn-transmission-selection-algo.cc b/contrib/tsn/model/tsn-transmission-selection-algo.cc
index 45d930a..477469c 100644
--- a/contrib/tsn/model/tsn-transmission-selection-algo.cc
+++ b/contrib/tsn/model/tsn-transmission-selection-algo.cc
@@ -90,13 +90,18 @@ TsnTransmissionSelectionAlgo::UpdateTransmissionGate(bool IsOpen)
   m_transmissionGateIsOpen = IsOpen;
 }
 
+void
+TsnTransmissionSelectionAlgo::Update()
+{
+  NS_LOG_FUNCTION(this);
+}
+
 Time
 TsnTransmissionSelectionAlgo::GetHardwareLatency()
 {
   NS_LOG_FUNCTION(this);
   Ptr<UniformRandomVariable> randVar = CreateObject<UniformRandomVariable>();
   return NanoSeconds(randVar->GetValue(m_minLatencyOverhead.GetNanoSeconds(), m_maxLatencyOverhead.GetNanoSeconds()));
-
 }
 
 };
diff --git a/contrib/tsn/model/tsn-transmission-selection-algo.h b/contrib/tsn/model/tsn-transmission-selection-algo.h
index 674d66e..3bcd25f 100644
--- a/contrib/tsn/model/tsn-transmission-selection-algo.h
+++ b/contrib/tsn/model/tsn-transmission-selection-algo.h
@@ -48,6 +48,7 @@ class TsnTransmissionSelectionAlgo: public Object
     virtual void TransmitComplete(Ptr<Packet> p);
 
     virtual void UpdateTransmissionGate(bool IsOpen);
+    virtual void Update();
 
     Time GetHardwareLatency();
 
@@ -59,7 +60,6 @@ class TsnTransmissionSelectionAlgo: public Object
     Callback<void> ReadyToTransmitCallback;
 
   private:
-
     Time m_minLatencyOverhead;
     Time m_maxLatencyOverhead;
 };