Paper/patches/unapplied/server/0632-Synchronize-PalettedContainer-instead-of-ThreadingDe.patch
2023-06-07 19:06:55 +02:00

92 lines
4.4 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Fri, 29 May 2020 20:29:02 -0400
Subject: [PATCH] Synchronize PalettedContainer instead of
ThreadingDetector/Semaphore
Mojang has flaws in their logic about chunks being concurrently
wrote to. So we constantly see crashes around multiple threads writing.
Additionally, java has optimized synchronization so well that its
in many times faster than trying to manage read write locks for low
contention situations.
And this is extremely a low contention situation.
diff --git a/src/main/java/net/minecraft/world/level/chunk/PalettedContainer.java b/src/main/java/net/minecraft/world/level/chunk/PalettedContainer.java
index 34804dc42c7a18108126c14c1b5f3d5a9a46f83d..4cbceb1c18dbee75ac5154ff0c15a4e79bd31575 100644
--- a/src/main/java/net/minecraft/world/level/chunk/PalettedContainer.java
+++ b/src/main/java/net/minecraft/world/level/chunk/PalettedContainer.java
@@ -32,14 +32,14 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
private final T @org.jetbrains.annotations.Nullable [] presetValues; // Paper - Anti-Xray - Add preset values
private volatile PalettedContainer.Data<T> data;
private final PalettedContainer.Strategy strategy;
- private final ThreadingDetector threadingDetector = new ThreadingDetector("PalettedContainer");
+ // private final ThreadingDetector threadingDetector = new ThreadingDetector("PalettedContainer"); // Paper - unused
public void acquire() {
- this.threadingDetector.checkAndLock();
+ // this.threadingDetector.checkAndLock(); // Paper - disable this - use proper synchronization
}
public void release() {
- this.threadingDetector.checkAndUnlock();
+ // this.threadingDetector.checkAndUnlock(); // Paper - disable this
}
// Paper start - Anti-Xray - Add preset values
@@ -129,7 +129,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
}
@Override
- public int onResize(int newBits, T object) {
+ public synchronized int onResize(int newBits, T object) { // Paper - synchronize
PalettedContainer.Data<T> data = this.data;
// Paper start - Anti-Xray - Add preset values
@@ -176,7 +176,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
return this.getAndSet(this.strategy.getIndex(x, y, z), value);
}
- private T getAndSet(int index, T value) {
+ private synchronized T getAndSet(int index, T value) { // Paper - synchronize
int i = this.data.palette.idFor(value);
int j = this.data.storage.getAndSet(index, i);
return this.data.palette.valueFor(j);
@@ -193,7 +193,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
}
- private void set(int index, T value) {
+ private synchronized void set(int index, T value) { // Paper - synchronize
int i = this.data.palette.idFor(value);
this.data.storage.set(index, i);
}
@@ -218,7 +218,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
});
}
- public void read(FriendlyByteBuf buf) {
+ public synchronized void read(FriendlyByteBuf buf) { // Paper - synchronize
this.acquire();
try {
@@ -238,7 +238,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
@Override
@Deprecated @io.papermc.paper.annotation.DoNotUse public void write(FriendlyByteBuf buf) { this.write(buf, null, 0); }
@Override
- public void write(FriendlyByteBuf buf, @Nullable com.destroystokyo.paper.antixray.ChunkPacketInfo<T> chunkPacketInfo, int bottomBlockY) {
+ public synchronized void write(FriendlyByteBuf buf, @Nullable com.destroystokyo.paper.antixray.ChunkPacketInfo<T> chunkPacketInfo, int bottomBlockY) { // Paper - synchronize
this.acquire();
try {
@@ -300,7 +300,7 @@ public class PalettedContainer<T> implements PaletteResize<T>, PalettedContainer
}
@Override
- public PalettedContainerRO.PackedData<T> pack(IdMap<T> idList, PalettedContainer.Strategy paletteProvider) {
+ public synchronized PalettedContainerRO.PackedData<T> pack(IdMap<T> idList, PalettedContainer.Strategy paletteProvider) { // Paper - synchronize
this.acquire();
PalettedContainerRO.PackedData var12;