From bcd5a9235c2aa21bcd091d3088d90a9e2f94b8dc Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Tue, 20 Nov 2018 15:50:41 +0100
Subject: [PATCH] [dxvk] Make use of VK_AMD_memory_overallocation_behavior

Currently only supported on AMDVLK. Enforces memory limits on a driver
level unless the corresponding dxvk.allowMemoryOvercommit option is enabled.
---
 src/dxvk/dxvk_adapter.cpp  | 15 ++++++++++++++-
 src/dxvk/dxvk_extensions.h |  1 +
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/dxvk/dxvk_adapter.cpp b/src/dxvk/dxvk_adapter.cpp
index 9c166825..adea2900 100644
--- a/src/dxvk/dxvk_adapter.cpp
+++ b/src/dxvk/dxvk_adapter.cpp
@@ -212,7 +212,8 @@ namespace dxvk {
   Rc<DxvkDevice> DxvkAdapter::createDevice(DxvkDeviceFeatures enabledFeatures) {
     DxvkDeviceExtensions devExtensions;
 
-    std::array<DxvkExt*, 12> devExtensionList = {{
+    std::array<DxvkExt*, 13> devExtensionList = {{
+      &devExtensions.amdMemoryOverallocationBehaviour,
       &devExtensions.extShaderViewportIndexLayer,
       &devExtensions.extTransformFeedback,
       &devExtensions.extVertexAttributeDivisor,
@@ -254,6 +255,15 @@ namespace dxvk {
       enabledFeatures.extVertexAttributeDivisor.pNext = enabledFeatures.core.pNext;
       enabledFeatures.core.pNext = &enabledFeatures.extVertexAttributeDivisor;
     }
+
+    // Report the desired overallocation behaviour to the driver
+    VkDeviceMemoryOverallocationCreateInfoAMD overallocInfo;
+    overallocInfo.sType = VK_STRUCTURE_TYPE_DEVICE_MEMORY_OVERALLOCATION_CREATE_INFO_AMD;
+    overallocInfo.pNext = nullptr;
+    overallocInfo.overallocationBehavior = VK_MEMORY_OVERALLOCATION_BEHAVIOR_DISALLOWED_AMD;
+
+    if (m_instance->options().allowMemoryOvercommit)
+      overallocInfo.overallocationBehavior = VK_MEMORY_OVERALLOCATION_BEHAVIOR_ALLOWED_AMD;
     
     // Create one single queue for graphics and present
     float queuePriority = 1.0f;
@@ -288,6 +298,9 @@ namespace dxvk {
     info.enabledExtensionCount      = extensionNameList.count();
     info.ppEnabledExtensionNames    = extensionNameList.names();
     info.pEnabledFeatures           = &enabledFeatures.core.features;
+
+    if (devExtensions.amdMemoryOverallocationBehaviour)
+      overallocInfo.pNext = std::exchange(info.pNext, &overallocInfo);
     
     VkDevice device = VK_NULL_HANDLE;
     
diff --git a/src/dxvk/dxvk_extensions.h b/src/dxvk/dxvk_extensions.h
index 12160b5c..401d42b1 100644
--- a/src/dxvk/dxvk_extensions.h
+++ b/src/dxvk/dxvk_extensions.h
@@ -257,6 +257,7 @@ namespace dxvk {
    * used by DXVK if supported by the implementation.
    */
   struct DxvkDeviceExtensions {
+    DxvkExt amdMemoryOverallocationBehaviour= { VK_AMD_MEMORY_OVERALLOCATION_BEHAVIOR_EXTENSION_NAME,   DxvkExtMode::Optional };
     DxvkExt extShaderViewportIndexLayer     = { VK_EXT_SHADER_VIEWPORT_INDEX_LAYER_EXTENSION_NAME,      DxvkExtMode::Optional };
     DxvkExt extTransformFeedback            = { VK_EXT_TRANSFORM_FEEDBACK_EXTENSION_NAME,               DxvkExtMode::Optional };
     DxvkExt extVertexAttributeDivisor       = { VK_EXT_VERTEX_ATTRIBUTE_DIVISOR_EXTENSION_NAME,         DxvkExtMode::Optional };