diff --git a/Source/Engine/Engine/NativeInterop.Managed.cs b/Source/Engine/Engine/NativeInterop.Managed.cs index c7507c778..148efb007 100644 --- a/Source/Engine/Engine/NativeInterop.Managed.cs +++ b/Source/Engine/Engine/NativeInterop.Managed.cs @@ -176,6 +176,7 @@ namespace FlaxEngine.Interop _managedHandle.Free(); _unmanagedData = IntPtr.Zero; } + _arrayType = _elementType = null; ManagedArrayPool.Put(this); } @@ -442,22 +443,25 @@ namespace FlaxEngine.Interop /// /// Tries to free all references to old weak handles so GC can collect them. /// - internal static void TryCollectWeakHandles() + internal static void TryCollectWeakHandles(bool force = false) { - if (weakHandleAccumulator < nextWeakPoolCollection) - return; + if (!force) + { + if (weakHandleAccumulator < nextWeakPoolCollection) + return; - nextWeakPoolCollection = weakHandleAccumulator + 1000; + nextWeakPoolCollection = weakHandleAccumulator + 1000; - // Try to swap pools after garbage collection or whenever the pool gets too large - var gc0CollectionCount = GC.CollectionCount(0); - if (gc0CollectionCount < nextWeakPoolGCCollection && weakPool.Count < WeakPoolCollectionSizeThreshold) - return; - nextWeakPoolGCCollection = gc0CollectionCount + 1; + // Try to swap pools after garbage collection or whenever the pool gets too large + var gc0CollectionCount = GC.CollectionCount(0); + if (gc0CollectionCount < nextWeakPoolGCCollection && weakPool.Count < WeakPoolCollectionSizeThreshold) + return; + nextWeakPoolGCCollection = gc0CollectionCount + 1; - // Prevent huge allocations from swapping the pools in the middle of the operation - if (System.Diagnostics.Stopwatch.GetElapsedTime(lastWeakPoolCollectionTime).TotalMilliseconds < WeakPoolCollectionTimeThreshold) - return; + // Prevent huge allocations from swapping the pools in the middle of the operation + if (System.Diagnostics.Stopwatch.GetElapsedTime(lastWeakPoolCollectionTime).TotalMilliseconds < WeakPoolCollectionTimeThreshold) + return; + } lastWeakPoolCollectionTime = System.Diagnostics.Stopwatch.GetTimestamp(); // Swap the pools and release the oldest pool for GC diff --git a/Source/Engine/Engine/NativeInterop.Unmanaged.cs b/Source/Engine/Engine/NativeInterop.Unmanaged.cs index 71caee1e9..618dd8564 100644 --- a/Source/Engine/Engine/NativeInterop.Unmanaged.cs +++ b/Source/Engine/Engine/NativeInterop.Unmanaged.cs @@ -1054,7 +1054,49 @@ namespace FlaxEngine.Interop } [UnmanagedCallersOnly] - internal static void ReloadScriptingAssemblyLoadContext() + internal static void CreateScriptingAssemblyLoadContext() + { +#if FLAX_EDITOR + if (scriptingAssemblyLoadContext != null) + { + // Wait for previous ALC to finish unloading, track it without holding strong references to it + GCHandle weakRef = GCHandle.Alloc(scriptingAssemblyLoadContext, GCHandleType.WeakTrackResurrection); + scriptingAssemblyLoadContext = null; +#if true + // In case the ALC doesn't unload properly: https://learn.microsoft.com/en-us/dotnet/standard/assembly/unloadability#debug-unloading-issues + while (true) +#else + for (int attempts = 5; attempts > 0; attempts--) +#endif + { + GC.Collect(); + GC.WaitForPendingFinalizers(); + + if (!IsHandleAlive(weakRef)) + break; + System.Threading.Thread.Sleep(1); + } + if (IsHandleAlive(weakRef)) + Debug.LogWarning("Scripting AssemblyLoadContext was not unloaded."); + weakRef.Free(); + + static bool IsHandleAlive(GCHandle weakRef) + { + // Checking the target in scope somehow holds a reference to it...? + return weakRef.Target != null; + } + } + + scriptingAssemblyLoadContext = new AssemblyLoadContext("Flax", isCollectible: true); + scriptingAssemblyLoadContext.Resolving += OnScriptingAssemblyLoadContextResolving; +#else + scriptingAssemblyLoadContext = new AssemblyLoadContext("Flax", isCollectible: false); +#endif + DelegateHelpers.InitMethods(); + } + + [UnmanagedCallersOnly] + internal static void UnloadScriptingAssemblyLoadContext() { #if FLAX_EDITOR // Clear all caches which might hold references to assemblies in collectible ALC @@ -1072,24 +1114,73 @@ namespace FlaxEngine.Interop handle.Free(); propertyHandleCacheCollectible.Clear(); + foreach (var key in assemblyHandles.Keys.Where(x => x.IsCollectible)) + assemblyHandles.Remove(key); + foreach (var key in assemblyOwnedNativeLibraries.Keys.Where(x => x.IsCollectible)) + assemblyOwnedNativeLibraries.Remove(key); + _typeSizeCache.Clear(); foreach (var pair in classAttributesCacheCollectible) pair.Value.Free(); classAttributesCacheCollectible.Clear(); + ArrayFactory.marshalledTypes.Clear(); + ArrayFactory.arrayTypes.Clear(); + ArrayFactory.createArrayDelegates.Clear(); + FlaxEngine.Json.JsonSerializer.ResetCache(); + DelegateHelpers.Release(); + + // Ensure both pools are empty + ManagedHandle.ManagedHandlePool.TryCollectWeakHandles(true); + ManagedHandle.ManagedHandlePool.TryCollectWeakHandles(true); + + GC.Collect(); + GC.WaitForPendingFinalizers(); + + { + // HACK: Workaround for TypeDescriptor holding references to collectible types (https://github.com/dotnet/runtime/issues/30656) + + Type TypeDescriptionProviderType = typeof(System.ComponentModel.TypeDescriptionProvider); + MethodInfo clearCacheMethod = TypeDescriptionProviderType?.Assembly.GetType("System.ComponentModel.ReflectionCachesUpdateHandler")?.GetMethod("ClearCache"); + if (clearCacheMethod != null) + clearCacheMethod.Invoke(null, new object[] { null }); + else + { + MethodInfo beforeUpdateMethod = TypeDescriptionProviderType?.Assembly.GetType("System.ComponentModel.ReflectionCachesUpdateHandler")?.GetMethod("BeforeUpdate"); + if (beforeUpdateMethod != null) + beforeUpdateMethod.Invoke(null, new object[] { null }); + } + + Type TypeDescriptorType = typeof(System.ComponentModel.TypeDescriptor); + + object s_internalSyncObject = TypeDescriptorType?.GetField("s_internalSyncObject", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)?.GetValue(null); + System.Collections.Hashtable s_defaultProviders = (System.Collections.Hashtable)TypeDescriptorType?.GetField("s_defaultProviders", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)?.GetValue(null); + if (s_internalSyncObject != null && s_defaultProviders != null) + { + lock (s_internalSyncObject) + s_defaultProviders.Clear(); + } + + object s_providerTable = TypeDescriptorType?.GetField("s_providerTable", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)?.GetValue(null); + System.Collections.Hashtable s_providerTypeTable = (System.Collections.Hashtable)TypeDescriptorType?.GetField("s_providerTypeTable", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic)?.GetValue(null); + if (s_providerTable != null && s_providerTypeTable != null) + { + lock (s_providerTable) + s_providerTypeTable.Clear(); + TypeDescriptorType.GetField("s_providerTable", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic) + ?.FieldType.GetMethods(BindingFlags.Instance | BindingFlags.Public).FirstOrDefault(x => x.Name == "Clear") + ?.Invoke(s_providerTable, new object[] { }); + } + } // Unload the ALC - bool unloading = true; - scriptingAssemblyLoadContext.Unloading += (alc) => { unloading = false; }; scriptingAssemblyLoadContext.Unload(); + scriptingAssemblyLoadContext.Resolving -= OnScriptingAssemblyLoadContextResolving; - while (unloading) - System.Threading.Thread.Sleep(1); - - InitScriptingAssemblyLoadContext(); - DelegateHelpers.InitMethods(); + GC.Collect(); + GC.WaitForPendingFinalizers(); #endif } diff --git a/Source/Engine/Engine/NativeInterop.cs b/Source/Engine/Engine/NativeInterop.cs index 35fe70221..7a9a8e5ff 100644 --- a/Source/Engine/Engine/NativeInterop.cs +++ b/Source/Engine/Engine/NativeInterop.cs @@ -73,19 +73,6 @@ namespace FlaxEngine.Interop return nativeLibrary; } - private static void InitScriptingAssemblyLoadContext() - { -#if FLAX_EDITOR - var isCollectible = true; -#else - var isCollectible = false; -#endif - scriptingAssemblyLoadContext = new AssemblyLoadContext("Flax", isCollectible); -#if FLAX_EDITOR - scriptingAssemblyLoadContext.Resolving += OnScriptingAssemblyLoadContextResolving; -#endif - } - [UnmanagedCallersOnly] internal static unsafe void Init() { @@ -97,8 +84,6 @@ namespace FlaxEngine.Interop System.Threading.Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture; System.Threading.Thread.CurrentThread.CurrentUICulture = CultureInfo.InvariantCulture; - InitScriptingAssemblyLoadContext(); - DelegateHelpers.InitMethods(); } #if FLAX_EDITOR @@ -1475,11 +1460,11 @@ namespace FlaxEngine.Interop internal static class ArrayFactory { - private delegate Array CreateArrayDelegate(long size); + internal delegate Array CreateArrayDelegate(long size); - private static ConcurrentDictionary marshalledTypes = new ConcurrentDictionary(1, 3); - private static ConcurrentDictionary arrayTypes = new ConcurrentDictionary(1, 3); - private static ConcurrentDictionary createArrayDelegates = new ConcurrentDictionary(1, 3); + internal static ConcurrentDictionary marshalledTypes = new ConcurrentDictionary(1, 3); + internal static ConcurrentDictionary arrayTypes = new ConcurrentDictionary(1, 3); + internal static ConcurrentDictionary createArrayDelegates = new ConcurrentDictionary(1, 3); internal static Type GetMarshalledType(Type elementType) { @@ -1645,17 +1630,6 @@ namespace FlaxEngine.Interop return RegisterType(type, true).typeHolder; } - internal static (TypeHolder typeHolder, ManagedHandle handle) GetTypeHolderAndManagedHandle(Type type) - { - if (managedTypes.TryGetValue(type, out (TypeHolder typeHolder, ManagedHandle handle) tuple)) - return tuple; -#if FLAX_EDITOR - if (managedTypesCollectible.TryGetValue(type, out tuple)) - return tuple; -#endif - return RegisterType(type, true); - } - /// /// Returns a static ManagedHandle to TypeHolder for given Type, and caches it if needed. /// @@ -1781,6 +1755,14 @@ namespace FlaxEngine.Interop #endif } + internal static void Release() + { + MakeNewCustomDelegateFunc = null; +#if FLAX_EDITOR + MakeNewCustomDelegateFuncCollectible = null; +#endif + } + internal static Type MakeNewCustomDelegate(Type[] parameters) { #if FLAX_EDITOR diff --git a/Source/Engine/Scripting/ManagedCLR/MCore.h b/Source/Engine/Scripting/ManagedCLR/MCore.h index 35227df56..d975f5af7 100644 --- a/Source/Engine/Scripting/ManagedCLR/MCore.h +++ b/Source/Engine/Scripting/ManagedCLR/MCore.h @@ -45,9 +45,16 @@ public: /// static void UnloadEngine(); + /// + /// Creates the assembly load context for assemblies used by Scripting. + /// + static void CreateScriptingAssemblyLoadContext(); + #if USE_EDITOR - // Called by Scripting in a middle of hot-reload (after unloading modules but before loading them again). - static void ReloadScriptingAssemblyLoadContext(); + /// + /// Called by Scripting in a middle of hot-reload (after unloading modules but before loading them again). + /// + static void UnloadScriptingAssemblyLoadContext(); #endif public: diff --git a/Source/Engine/Scripting/Runtime/DotNet.cpp b/Source/Engine/Scripting/Runtime/DotNet.cpp index ddafab614..29ccea8ae 100644 --- a/Source/Engine/Scripting/Runtime/DotNet.cpp +++ b/Source/Engine/Scripting/Runtime/DotNet.cpp @@ -330,9 +330,15 @@ void MCore::UnloadEngine() ShutdownHostfxr(); } +void MCore::CreateScriptingAssemblyLoadContext() +{ + static void* CreateScriptingAssemblyLoadContextPtr = GetStaticMethodPointer(TEXT("CreateScriptingAssemblyLoadContext")); + CallStaticMethod(CreateScriptingAssemblyLoadContextPtr); +} + #if USE_EDITOR -void MCore::ReloadScriptingAssemblyLoadContext() +void MCore::UnloadScriptingAssemblyLoadContext() { // Clear any cached class attributes (see https://github.com/FlaxEngine/FlaxEngine/issues/1108) for (auto e : CachedClassHandles) @@ -377,8 +383,8 @@ void MCore::ReloadScriptingAssemblyLoadContext() } } - static void* ReloadScriptingAssemblyLoadContextPtr = GetStaticMethodPointer(TEXT("ReloadScriptingAssemblyLoadContext")); - CallStaticMethod(ReloadScriptingAssemblyLoadContextPtr); + static void* UnloadScriptingAssemblyLoadContextPtr = GetStaticMethodPointer(TEXT("UnloadScriptingAssemblyLoadContext")); + CallStaticMethod(UnloadScriptingAssemblyLoadContextPtr); } #endif diff --git a/Source/Engine/Scripting/Runtime/Mono.cpp b/Source/Engine/Scripting/Runtime/Mono.cpp index 351e1569b..f4da8135c 100644 --- a/Source/Engine/Scripting/Runtime/Mono.cpp +++ b/Source/Engine/Scripting/Runtime/Mono.cpp @@ -715,9 +715,13 @@ void MCore::UnloadEngine() #endif } +void MCore::CreateScriptingAssemblyLoadContext() +{ +} + #if USE_EDITOR -void MCore::ReloadScriptingAssemblyLoadContext() +void MCore::UnloadScriptingAssemblyLoadContext() { } diff --git a/Source/Engine/Scripting/Runtime/None.cpp b/Source/Engine/Scripting/Runtime/None.cpp index 8731ed00d..98bf1f012 100644 --- a/Source/Engine/Scripting/Runtime/None.cpp +++ b/Source/Engine/Scripting/Runtime/None.cpp @@ -58,9 +58,13 @@ void MCore::UnloadEngine() MRootDomain = nullptr; } +void MCore::CreateScriptingAssemblyLoadContext() +{ +} + #if USE_EDITOR -void MCore::ReloadScriptingAssemblyLoadContext() +void MCore::UnloadScriptingAssemblyLoadContext() { } diff --git a/Source/Engine/Scripting/Scripting.cpp b/Source/Engine/Scripting/Scripting.cpp index 4731a088d..75d68394d 100644 --- a/Source/Engine/Scripting/Scripting.cpp +++ b/Source/Engine/Scripting/Scripting.cpp @@ -182,6 +182,8 @@ bool ScriptingService::Init() return true; } + MCore::CreateScriptingAssemblyLoadContext(); + // Cache root domain _rootDomain = MCore::GetRootDomain(); @@ -710,7 +712,8 @@ void Scripting::Reload(bool canTriggerSceneReload) _hasGameModulesLoaded = false; // Release and create a new assembly load context for user assemblies - MCore::ReloadScriptingAssemblyLoadContext(); + MCore::UnloadScriptingAssemblyLoadContext(); + MCore::CreateScriptingAssemblyLoadContext(); // Give GC a try to cleanup old user objects and the other mess MCore::GC::Collect();