From 8a5f26b0648609054e72c03a5af053d7637c4ebf Mon Sep 17 00:00:00 2001
From: cnderrauber <zengjiestc@gmail.com>
Date: Wed, 19 Jan 2022 10:24:29 +0800
Subject: [PATCH] refine reuse transceiver (#348)

---
 pkg/rtc/mediatracksubscriptions.go | 78 +++++++++++++++---------------
 pkg/rtc/participant.go             |  8 +--
 2 files changed, 43 insertions(+), 43 deletions(-)

diff --git a/pkg/rtc/mediatracksubscriptions.go b/pkg/rtc/mediatracksubscriptions.go
index 2042ca2f0..535637429 100644
--- a/pkg/rtc/mediatracksubscriptions.go
+++ b/pkg/rtc/mediatracksubscriptions.go
@@ -188,51 +188,49 @@ func (t *MediaTrackSubscriptions) AddSubscriber(sub types.LocalParticipant, code
 	})
 
 	downTrack.OnCloseHandler(func() {
-		go func() {
-			t.subscribedTracksMu.Lock()
-			delete(t.subscribedTracks, subscriberID)
-			t.subscribedTracksMu.Unlock()
+		t.subscribedTracksMu.Lock()
+		delete(t.subscribedTracks, subscriberID)
+		t.subscribedTracksMu.Unlock()
 
-			t.maybeNotifyNoSubscribers()
+		t.maybeNotifyNoSubscribers()
 
-			t.params.Telemetry.TrackUnsubscribed(context.Background(), subscriberID, t.params.MediaTrack.ToProto())
+		t.params.Telemetry.TrackUnsubscribed(context.Background(), subscriberID, t.params.MediaTrack.ToProto())
 
-			// ignore if the subscribing sub is not connected
-			if sub.SubscriberPC().ConnectionState() == webrtc.PeerConnectionStateClosed {
+		// ignore if the subscribing sub is not connected
+		if sub.SubscriberPC().ConnectionState() == webrtc.PeerConnectionStateClosed {
+			return
+		}
+
+		// if the source has been terminated, we'll need to terminate all of the subscribedtracks
+		// however, if the dest sub has disconnected, then we can skip
+		if sender == nil {
+			return
+		}
+		t.params.Logger.Debugw("removing peerconnection track",
+			"track", t.params.MediaTrack.ID(),
+			"subscriber", sub.Identity(),
+			"subscriberID", subscriberID,
+			"kind", t.params.MediaTrack.Kind(),
+		)
+		if err := sub.SubscriberPC().RemoveTrack(sender); err != nil {
+			if err == webrtc.ErrConnectionClosed {
+				// sub closing, can skip removing subscribedtracks
 				return
 			}
-
-			// if the source has been terminated, we'll need to terminate all of the subscribedtracks
-			// however, if the dest sub has disconnected, then we can skip
-			if sender == nil {
-				return
-			}
-			t.params.Logger.Debugw("removing peerconnection track",
-				"track", t.params.MediaTrack.ID(),
-				"subscriber", sub.Identity(),
-				"subscriberID", subscriberID,
-				"kind", t.params.MediaTrack.Kind(),
-			)
-			if err := sub.SubscriberPC().RemoveTrack(sender); err != nil {
-				if err == webrtc.ErrConnectionClosed {
-					// sub closing, can skip removing subscribedtracks
-					return
-				}
-				if _, ok := err.(*rtcerr.InvalidStateError); !ok {
-					// most of these are safe to ignore, since the track state might have already
-					// been set to Inactive
-					t.params.Logger.Debugw("could not remove remoteTrack from forwarder",
-						"error", err,
-						"subscriber", sub.Identity(),
-						"subscriberID", subscriberID,
-					)
-				}
+			if _, ok := err.(*rtcerr.InvalidStateError); !ok {
+				// most of these are safe to ignore, since the track state might have already
+				// been set to Inactive
+				t.params.Logger.Debugw("could not remove remoteTrack from forwarder",
+					"error", err,
+					"subscriber", sub.Identity(),
+					"subscriberID", subscriberID,
+				)
 			}
+		}
 
-			t.NotifySubscriberMaxQuality(subscriberID, livekit.VideoQuality_OFF)
-			sub.RemoveSubscribedTrack(subTrack)
-			sub.Negotiate()
-		}()
+		t.NotifySubscriberMaxQuality(subscriberID, livekit.VideoQuality_OFF)
+		sub.RemoveSubscribedTrack(subTrack)
+		sub.Negotiate()
 	})
 
 	t.subscribedTracks[subscriberID] = subTrack
@@ -259,7 +257,7 @@ func (t *MediaTrackSubscriptions) RemoveSubscriber(participantID livekit.Partici
 	t.subscribedTracksMu.Unlock()
 
 	if subTrack != nil {
-		go subTrack.DownTrack().Close()
+		subTrack.DownTrack().Close()
 	}
 
 	t.maybeNotifyNoSubscribers()
@@ -274,7 +272,7 @@ func (t *MediaTrackSubscriptions) RemoveAllSubscribers() {
 	t.subscribedTracksMu.Unlock()
 
 	for _, subTrack := range subscribedTracks {
-		go subTrack.DownTrack().Close()
+		subTrack.DownTrack().Close()
 	}
 
 	t.maybeNotifyNoSubscribers()
diff --git a/pkg/rtc/participant.go b/pkg/rtc/participant.go
index 605b0e199..58aa0c65d 100644
--- a/pkg/rtc/participant.go
+++ b/pkg/rtc/participant.go
@@ -1489,15 +1489,17 @@ func (p *ParticipantImpl) rtcpSendWorker() {
 
 		fwdPkts := make([]rtcp.Packet, 0, len(pkts))
 		for _, pkt := range pkts {
-			switch pkt.(type) {
+			switch packet := pkt.(type) {
 			case *rtcp.PictureLossIndication:
-				mediaSSRC := pkt.(*rtcp.PictureLossIndication).MediaSSRC
+				mediaSSRC := packet.MediaSSRC
 				if p.pliThrottle.canSend(mediaSSRC) {
+					p.params.Logger.Debugw("send pli", "ssrc", mediaSSRC)
 					fwdPkts = append(fwdPkts, pkt)
 				}
 			case *rtcp.FullIntraRequest:
-				mediaSSRC := pkt.(*rtcp.FullIntraRequest).MediaSSRC
+				mediaSSRC := packet.MediaSSRC
 				if p.pliThrottle.canSend(mediaSSRC) {
+					p.params.Logger.Debugw("send fir", "ssrc", mediaSSRC)
 					fwdPkts = append(fwdPkts, pkt)
 				}
 			default: