From 7947f33b2b6d5f3e06e0fb2c01fbc14e05cc054a Mon Sep 17 00:00:00 2001
From: Stefano Avallone <stavallo@gmail.com>
Date: Sat, 22 Jun 2024 16:24:41 +0200
Subject: [PATCH] wifi: Add a StaWifiMac trace source to notify of EMLSR link
 switch events

---
 src/wifi/model/sta-wifi-mac.cc | 13 ++++++++++++-
 src/wifi/model/sta-wifi-mac.h  | 16 ++++++++++------
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/wifi/model/sta-wifi-mac.cc b/src/wifi/model/sta-wifi-mac.cc
index 0d73ef101..72bad2e83 100644
--- a/src/wifi/model/sta-wifi-mac.cc
+++ b/src/wifi/model/sta-wifi-mac.cc
@@ -137,7 +137,15 @@ StaWifiMac::GetTypeId()
             .AddTraceSource("ReceivedBeaconInfo",
                             "Information about every received Beacon frame",
                             MakeTraceSourceAccessor(&StaWifiMac::m_beaconInfo),
-                            "ns3::ApInfo::TracedCallback");
+                            "ns3::ApInfo::TracedCallback")
+            .AddTraceSource("EmlsrLinkSwitch",
+                            "Trace start/end of EMLSR link switch events: when a PHY operating on "
+                            "a link starts switching, provides the ID of the link and a null "
+                            "pointer (indicating no PHY is operating on that link); when a PHY "
+                            "completes switching to a link, provides the ID of the link and a "
+                            "pointer to the PHY (that is now operating on that link)",
+                            MakeTraceSourceAccessor(&StaWifiMac::m_emlsrLinkSwitchLogger),
+                            "ns3::StaWifiMac::EmlsrLinkSwitchCallback");
     return tid;
 }
 
@@ -2024,6 +2032,7 @@ StaWifiMac::NotifySwitchingEmlsrLink(Ptr<WifiPhy> phy, uint8_t linkId, Time dela
         if (link->phy == phy && id != linkId)
         {
             link->phy = nullptr;
+            m_emlsrLinkSwitchLogger(id, nullptr);
         }
     }
 
@@ -2045,6 +2054,8 @@ StaWifiMac::NotifySwitchingEmlsrLink(Ptr<WifiPhy> phy, uint8_t linkId, Time dela
         newLink.feManager->SetWifiPhy(phy);
         // Connect the station manager on the new link to the given PHY
         newLink.stationManager->SetupPhy(phy);
+        // log link switch
+        m_emlsrLinkSwitchLogger(linkId, phy);
     };
 
     // cancel any pending event for the given PHY to switch link
diff --git a/src/wifi/model/sta-wifi-mac.h b/src/wifi/model/sta-wifi-mac.h
index 24b674887..e7d617a43 100644
--- a/src/wifi/model/sta-wifi-mac.h
+++ b/src/wifi/model/sta-wifi-mac.h
@@ -608,15 +608,19 @@ class StaWifiMac : public WifiMac
     /// store the UL TID-to-Link Mapping included in the Association Request frame
     WifiTidLinkMapping m_ulTidLinkMappingInAssocReq;
 
-    TracedCallback<Mac48Address> m_assocLogger;             ///< association logger
-    TracedCallback<uint8_t, Mac48Address> m_setupCompleted; ///< link setup completed logger
-    TracedCallback<Mac48Address> m_deAssocLogger;           ///< disassociation logger
-    TracedCallback<uint8_t, Mac48Address> m_setupCanceled;  ///< link setup canceled logger
-    TracedCallback<Time> m_beaconArrival;                   ///< beacon arrival logger
-    TracedCallback<ApInfo> m_beaconInfo;                    ///< beacon info logger
+    TracedCallback<Mac48Address> m_assocLogger;                    ///< association logger
+    TracedCallback<uint8_t, Mac48Address> m_setupCompleted;        ///< link setup completed logger
+    TracedCallback<Mac48Address> m_deAssocLogger;                  ///< disassociation logger
+    TracedCallback<uint8_t, Mac48Address> m_setupCanceled;         ///< link setup canceled logger
+    TracedCallback<Time> m_beaconArrival;                          ///< beacon arrival logger
+    TracedCallback<ApInfo> m_beaconInfo;                           ///< beacon info logger
+    TracedCallback<uint8_t, Ptr<WifiPhy>> m_emlsrLinkSwitchLogger; ///< EMLSR link switch logger
 
     /// TracedCallback signature for link setup completed/canceled events
     using LinkSetupCallback = void (*)(uint8_t /* link ID */, Mac48Address /* AP address */);
+
+    /// TracedCallback signature for EMLSR link switch events
+    using EmlsrLinkSwitchCallback = void (*)(uint8_t /* link ID */, Ptr<WifiPhy> /* PHY */);
 };
 
 /**