From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Spottedleaf Date: Sat, 4 Apr 2020 15:27:44 -0700 Subject: [PATCH] Allow controlled flushing for network manager Only make one flush call when emptying the packet queue too This patch will be used to optimise out flush calls in later patches. diff --git a/src/main/java/net/minecraft/network/Connection.java b/src/main/java/net/minecraft/network/Connection.java index c327609fdb7641e4dc5fb58d97903fa666eac24d..0b47144cb8ad72efebf10e163f5b442995ef213e 100644 --- a/src/main/java/net/minecraft/network/Connection.java +++ b/src/main/java/net/minecraft/network/Connection.java @@ -94,6 +94,39 @@ public class Connection extends SimpleChannelInboundHandler> { public ConnectionProtocol protocol; // Paper end + // Paper start - allow controlled flushing + volatile boolean canFlush = true; + private final java.util.concurrent.atomic.AtomicInteger packetWrites = new java.util.concurrent.atomic.AtomicInteger(); + private int flushPacketsStart; + private final Object flushLock = new Object(); + + public void disableAutomaticFlush() { + synchronized (this.flushLock) { + this.flushPacketsStart = this.packetWrites.get(); // must be volatile and before canFlush = false + this.canFlush = false; + } + } + + public void enableAutomaticFlush() { + synchronized (this.flushLock) { + this.canFlush = true; + if (this.packetWrites.get() != this.flushPacketsStart) { // must be after canFlush = true + this.flush(); // only make the flush call if we need to + } + } + } + + private final void flush() { + if (this.channel.eventLoop().inEventLoop()) { + this.channel.flush(); + } else { + this.channel.eventLoop().execute(() -> { + this.channel.flush(); + }); + } + } + // Paper end - allow controlled flushing + public Connection(PacketFlow side) { this.receiving = side; } @@ -255,7 +288,7 @@ public class Connection extends SimpleChannelInboundHandler> { net.minecraft.server.MCUtil.isMainThread() && packet.isReady() && this.queue.isEmpty() && (packet.getExtraPackets() == null || packet.getExtraPackets().isEmpty()) ))) { - this.sendPacket(packet, callback); + this.writePacket(packet, callback, null); // Paper return; } // write the packets to the queue, then flush - antixray hooks there already @@ -279,6 +312,14 @@ public class Connection extends SimpleChannelInboundHandler> { } private void sendPacket(Packet packet, @Nullable GenericFutureListener> callback) { + // Paper start - add flush parameter + this.writePacket(packet, callback, Boolean.TRUE); + } + private void writePacket(Packet packet, @Nullable GenericFutureListener> callback, Boolean flushConditional) { + this.packetWrites.getAndIncrement(); // must be befeore using canFlush + boolean effectiveFlush = flushConditional == null ? this.canFlush : flushConditional.booleanValue(); + final boolean flush = effectiveFlush || packet instanceof net.minecraft.network.protocol.game.ClientboundKeepAlivePacket || packet instanceof ClientboundDisconnectPacket; // no delay for certain packets + // Paper end - add flush parameter ConnectionProtocol enumprotocol = ConnectionProtocol.getProtocolForPacket(packet); ConnectionProtocol enumprotocol1 = this.getCurrentProtocol(); @@ -289,16 +330,21 @@ public class Connection extends SimpleChannelInboundHandler> { } if (this.channel.eventLoop().inEventLoop()) { - this.doSendPacket(packet, callback, enumprotocol, enumprotocol1); + this.doSendPacket(packet, callback, enumprotocol, enumprotocol1, flush); // Paper - add flush parameter } else { this.channel.eventLoop().execute(() -> { - this.doSendPacket(packet, callback, enumprotocol, enumprotocol1); + this.doSendPacket(packet, callback, enumprotocol, enumprotocol1, flush); // Paper - add flush parameter }); } } private void doSendPacket(Packet packet, @Nullable GenericFutureListener> genericfuturelistener, ConnectionProtocol enumprotocol, ConnectionProtocol enumprotocol1) { + // Paper start - add flush parameter + this.doSendPacket(packet, genericfuturelistener, enumprotocol, enumprotocol1, true); + } + private void doSendPacket(Packet packet, @Nullable GenericFutureListener> genericfuturelistener, ConnectionProtocol enumprotocol, ConnectionProtocol enumprotocol1, boolean flush) { + // Paper end - add flush parameter if (enumprotocol != enumprotocol1) { this.setProtocol(enumprotocol); } @@ -312,7 +358,7 @@ public class Connection extends SimpleChannelInboundHandler> { try { // Paper end - ChannelFuture channelfuture = this.channel.writeAndFlush(packet); + ChannelFuture channelfuture = flush ? this.channel.writeAndFlush(packet) : this.channel.write(packet); // Paper - add flush parameter if (genericfuturelistener != null) { channelfuture.addListener(genericfuturelistener); @@ -354,6 +400,10 @@ public class Connection extends SimpleChannelInboundHandler> { } private boolean processQueue() { if (this.queue.isEmpty()) return true; + // Paper start - make only one flush call per sendPacketQueue() call + final boolean needsFlush = this.canFlush; + boolean hasWrotePacket = false; + // Paper end - make only one flush call per sendPacketQueue() call // If we are on main, we are safe here in that nothing else should be processing queue off main anymore // But if we are not on main due to login/status, the parent is synchronized on packetQueue java.util.Iterator iterator = this.queue.iterator(); @@ -361,16 +411,22 @@ public class Connection extends SimpleChannelInboundHandler> { PacketHolder queued = iterator.next(); // poll -> peek // Fix NPE (Spigot bug caused by handleDisconnection()) - if (queued == null) { + if (false && queued == null) { // Paper - diff on change, this logic is redundant: iterator guarantees ret of an element - on change, hook the flush logic here return true; } Packet packet = queued.packet; if (!packet.isReady()) { + // Paper start - make only one flush call per sendPacketQueue() call + if (hasWrotePacket && (needsFlush || this.canFlush)) { + this.flush(); + } + // Paper end - make only one flush call per sendPacketQueue() call return false; } else { iterator.remove(); - this.sendPacket(packet, queued.listener); + this.writePacket(packet, queued.listener, (!iterator.hasNext() && (needsFlush || this.canFlush)) ? Boolean.TRUE : Boolean.FALSE); // Paper - make only one flush call per sendPacketQueue() call + hasWrotePacket = true; // Paper - make only one flush call per sendPacketQueue() call } } return true;