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geforkt von Mirrors/Paper
Paper/Spigot-Server-Patches/0448-Fix-Chunk-Post-Processing-deadlock-risk.patch
Jake Potrebic 69c09cdb00
Updated Upstream (CraftBukkit) (#5607)
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

CraftBukkit Changes:
e1a6197e SPIGOT-5565: Animals still spawn from chunk gen when spawn-animals=false
2021-05-11 00:22:11 +01:00

61 Zeilen
3.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 18 Apr 2020 04:36:11 -0400
Subject: [PATCH] Fix Chunk Post Processing deadlock risk
See: https://gist.github.com/aikar/dd22bbd2a3d78a2fd3d92e95e9f28dc6
as part of post processing a chunk, we can call ChunkConverter.
ChunkConverter then kicks off major physics updates, and when blocks
that have connections across chunk boundries occur, a recursive risk
can occur where A updates a block that triggers a physics request.
That physics request may trigger a chunk request, that then enqueues
a task into the Mailbox ChunkTaskQueueSorter.
If anything requests that same chunk that is in the middle of conversion,
it's mailbox queue is going to be held up, so the subsequent chunk request
will be unable to proceed.
We delay post processing of Chunk.A() 1 "pass" by re stuffing it back into
the executor so that the mailbox ChunkQueue is now considered empty.
This successfully fixed a reoccurring and highly reproduceable crash
for heightmaps.
diff --git a/src/main/java/net/minecraft/server/level/ChunkProviderServer.java b/src/main/java/net/minecraft/server/level/ChunkProviderServer.java
index 2d7d2e712a7117e6985e3104097a31a5577c1b82..6e5d21af43261dc2f12ceec7b7e3269be635cf7a 100644
--- a/src/main/java/net/minecraft/server/level/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/level/ChunkProviderServer.java
@@ -1019,6 +1019,7 @@ public class ChunkProviderServer extends IChunkProvider {
return super.executeNext() || execChunkTask; // Paper
}
} finally {
+ playerChunkMap.chunkLoadConversionCallbackExecutor.run(); // Paper - Add chunk load conversion callback executor to prevent deadlock due to recursion in the chunk task queue sorter
playerChunkMap.callbackExecutor.run();
}
// CraftBukkit end
diff --git a/src/main/java/net/minecraft/server/level/PlayerChunkMap.java b/src/main/java/net/minecraft/server/level/PlayerChunkMap.java
index 21bd5524af246cd19996dc8ec2e969d981cf8ee9..a7efc5c7e4da8f18ecfd6a335a01709db4259367 100644
--- a/src/main/java/net/minecraft/server/level/PlayerChunkMap.java
+++ b/src/main/java/net/minecraft/server/level/PlayerChunkMap.java
@@ -183,6 +183,8 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
};
// CraftBukkit end
+ final CallbackExecutor chunkLoadConversionCallbackExecutor = new CallbackExecutor(); // Paper
+
// Paper start - distance maps
private final com.destroystokyo.paper.util.misc.PooledLinkedHashSets<EntityPlayer> pooledLinkedPlayerHashSets = new com.destroystokyo.paper.util.misc.PooledLinkedHashSets<>();
@@ -1056,7 +1058,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
return Either.left(chunk);
});
}, (runnable) -> {
- this.mailboxMain.a(ChunkTaskQueueSorter.a(playerchunk, runnable));
+ this.mailboxMain.a(ChunkTaskQueueSorter.a(playerchunk, () -> PlayerChunkMap.this.chunkLoadConversionCallbackExecutor.execute(runnable))); // Paper - delay running Chunk post processing until outside of the sorter to prevent a deadlock scenario when post processing causes another chunk request.
});
completablefuture1.thenAcceptAsync((either) -> {