1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 6 Jul 2020 18:36:41 -0400
Subject: [PATCH] Fix Concurrency issue in ShufflingList
if multiple threads from worldgen sort at same time, it will crash.
So make a copy of the list for sorting purposes.
diff --git a/src/main/java/net/minecraft/world/entity/ai/behavior/GateBehavior.java b/src/main/java/net/minecraft/world/entity/ai/behavior/GateBehavior.java
index 419eadbe31b86b7192fd7a63268d547705e7c7ce..b45c4f50705f80163d44d9e588f86a5770f5be38 100644
--- a/src/main/java/net/minecraft/world/entity/ai/behavior/GateBehavior.java
+++ b/src/main/java/net/minecraft/world/entity/ai/behavior/GateBehavior.java
@@ -17,7 +17,7 @@ public class GateBehavior<E extends LivingEntity> implements BehaviorControl<E>
private final Set<MemoryModuleType<?>> exitErasedMemories;
private final GateBehavior.OrderPolicy orderPolicy;
private final GateBehavior.RunningPolicy runningPolicy;
- private final ShufflingList<BehaviorControl<? super E>> behaviors = new ShufflingList<>();
+ private final ShufflingList<BehaviorControl<? super E>> behaviors = new ShufflingList<>(false); // Paper - don't use a clone
private Behavior.Status status = Behavior.Status.STOPPED;
public GateBehavior(Map<MemoryModuleType<?>, MemoryStatus> requiredMemoryState, Set<MemoryModuleType<?>> memoriesToForgetWhenStopped, GateBehavior.OrderPolicy order, GateBehavior.RunningPolicy runMode, List<Pair<? extends BehaviorControl<? super E>, Integer>> tasks) {
diff --git a/src/main/java/net/minecraft/world/entity/ai/behavior/ShufflingList.java b/src/main/java/net/minecraft/world/entity/ai/behavior/ShufflingList.java
index 9fb20cd00568aeea25284ea0e80fe52cb1c3eede..731ef21dbbd25d6924717de42f4569a9b5935643 100644
--- a/src/main/java/net/minecraft/world/entity/ai/behavior/ShufflingList.java
+++ b/src/main/java/net/minecraft/world/entity/ai/behavior/ShufflingList.java
@@ -16,12 +16,25 @@ import net.minecraft.util.RandomSource;
public class ShufflingList<U> implements Iterable<U> {
protected final List<ShufflingList.WeightedEntry<U>> entries;
private final RandomSource random = RandomSource.create();
+ private final boolean isUnsafe; // Paper
public ShufflingList() {
+ // Paper start
+ this(true);
+ }
+ public ShufflingList(boolean isUnsafe) {
+ this.isUnsafe = isUnsafe;
+ // Paper end
this.entries = Lists.newArrayList();
}
private ShufflingList(List<ShufflingList.WeightedEntry<U>> list) {
+ // Paper start
+ this(list, true);
+ }
+ private ShufflingList(List<ShufflingList.WeightedEntry<U>> list, boolean isUnsafe) {
+ this.isUnsafe = isUnsafe;
+ // Paper end
this.entries = Lists.newArrayList(list);
}
@@ -37,11 +50,12 @@ public class ShufflingList<U> implements Iterable<U> {
}
public ShufflingList<U> shuffle() {
- this.entries.forEach((entry) -> {
- entry.setRandom(this.random.nextFloat());
- });
- this.entries.sort(Comparator.comparingDouble(ShufflingList.WeightedEntry::getRandWeight));
- return this;
+ // Paper start - make concurrent safe, work off a clone of the list
+ List<ShufflingList.WeightedEntry<U>> list = this.isUnsafe ? Lists.newArrayList(this.entries) : this.entries;
+ list.forEach(entry -> entry.setRandom(this.random.nextFloat()));
+ list.sort(Comparator.comparingDouble(ShufflingList.WeightedEntry::getRandWeight));
+ return this.isUnsafe ? new ShufflingList<>(list, this.isUnsafe) : this;
+ // Paper end
}
public Stream<U> stream() {
|
