PaperMC/Spigot-Server-Patches/0456-Allow-multiple-callbacks-to-schedule-for-Callback-Ex.patch
Josh Roy b31089a929
Updated Upstream (Bukkit/CraftBukkit/Spigot) (#5325)
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

Bukkit Changes:
d264e972 #591: Add option for a consumer before spawning an item
1c537fce #590: Add spawn and transform reasons for piglin zombification.

CraftBukkit Changes:
ee5006d1 #810: Add option for a consumer before spawning an item
f6a39d3c #809: Add spawn and transform reasons for piglin zombification.
0c24068a Organise imports

Spigot Changes:
bff52619 Organise imports
2021-03-08 15:12:31 -08:00

58 lines
2.4 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 21 Apr 2020 03:51:53 -0400
Subject: [PATCH] Allow multiple callbacks to schedule for Callback Executor
ChunkMapDistance polls multiple entries for pendingChunkUpdates
Each of these have the potential to move a chunk in and out of
"Loaded" state, which will result in multiple callbacks being
needed within a single tick of ChunkMapDistance
Use an ArrayDeque to store this Queue
We make sure to also implement a pattern that is recursion safe too.
diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
index 429355e5790148e2e061f67e44f0c8f96855f7c5..06124c8799846fd236f7ac1cad04e79bd30fc44c 100644
--- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
+++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
@@ -114,24 +114,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
public final CallbackExecutor callbackExecutor = new CallbackExecutor();
public static final class CallbackExecutor implements java.util.concurrent.Executor, Runnable {
- private Runnable queued;
+ // Paper start - replace impl with recursive safe multi entry queue
+ // it's possible to schedule multiple tasks currently, so it's vital we change this impl
+ // If we recurse into the executor again, we will append to another queue, ensuring task order consistency
+ private java.util.ArrayDeque<Runnable> queued = new java.util.ArrayDeque<>();
@Override
public void execute(Runnable runnable) {
- if (queued != null) {
- throw new IllegalStateException("Already queued");
+ if (queued == null) {
+ queued = new java.util.ArrayDeque<>();
}
- queued = runnable;
+ queued.add(runnable);
}
@Override
public void run() {
- Runnable task = queued;
+ if (queued == null) {
+ return;
+ }
+ java.util.ArrayDeque<Runnable> queue = queued;
queued = null;
- if (task != null) {
+ Runnable task;
+ while ((task = queue.pollFirst()) != null) {
task.run();
}
}
+ // Paper end
};
// CraftBukkit end