From bd7c4315328c7eb54e7b52e294aba9543c5ad1c4 Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Thu, 24 Mar 2016 23:30:01 -0700
Subject: [PATCH] Vulkan: Increase new size for new slabs.

---
 Common/Vulkan/VulkanMemory.cpp | 20 +++++++++++++++-----
 Common/Vulkan/VulkanMemory.h   |  5 +++--
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/Common/Vulkan/VulkanMemory.cpp b/Common/Vulkan/VulkanMemory.cpp
index 9eea7cd13f..cf7bbb2868 100644
--- a/Common/Vulkan/VulkanMemory.cpp
+++ b/Common/Vulkan/VulkanMemory.cpp
@@ -101,8 +101,8 @@ void VulkanPushBuffer::Defragment(VulkanContext *vulkan) {
 	assert(res);
 }
 
-VulkanDeviceAllocator::VulkanDeviceAllocator(VulkanContext *vulkan, size_t minSlabSize)
-	: vulkan_(vulkan), minSlabSize_(minSlabSize), memoryTypeIndex_(UNDEFINED_MEMORY_TYPE) {
+VulkanDeviceAllocator::VulkanDeviceAllocator(VulkanContext *vulkan, size_t minSlabSize, size_t maxSlabSize)
+	: vulkan_(vulkan), minSlabSize_(minSlabSize), maxSlabSize_(maxSlabSize), memoryTypeIndex_(UNDEFINED_MEMORY_TYPE) {
 	assert((minSlabSize_ & (SLAB_GRAIN_SIZE - 1)) == 0);
 }
 
@@ -268,6 +268,11 @@ void VulkanDeviceAllocator::ExecuteFree(FreeInfo *userdata) {
 }
 
 bool VulkanDeviceAllocator::AllocateSlab(size_t minBytes) {
+	if (!slabs_.empty() && minSlabSize_ < maxSlabSize_) {
+		// We're allocating an additional slab, so rachet up its size.
+		minSlabSize_ <<= 1;
+	}
+
 	VkMemoryAllocateInfo alloc = { VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO };
 	alloc.allocationSize = minSlabSize_;
 	alloc.memoryTypeIndex = memoryTypeIndex_;
@@ -297,7 +302,11 @@ void VulkanDeviceAllocator::Decimate() {
 	bool foundFree = false;
 
 	for (size_t i = 0; i < slabs_.size(); ++i) {
-		if (!slabs_[i].allocSizes.empty()) {
+		// Go backwards.  This way, we keep the largest free slab.
+		// We do this here (instead of the for) since size_t is unsigned.
+		size_t index = slabs_.size() - i - 1;
+
+		if (!slabs_[index].allocSizes.empty()) {
 			continue;
 		}
 
@@ -308,8 +317,9 @@ void VulkanDeviceAllocator::Decimate() {
 		}
 
 		// Okay, let's free this one up.
-		vulkan_->Delete().QueueDeleteDeviceMemory(slabs_[i].deviceMemory);
-		slabs_.erase(slabs_.begin() + i);
+		vulkan_->Delete().QueueDeleteDeviceMemory(slabs_[index].deviceMemory);
+		slabs_.erase(slabs_.begin() + index);
+
 		// Let's check the next one, which is now in this same slot.
 		--i;
 	}
diff --git a/Common/Vulkan/VulkanMemory.h b/Common/Vulkan/VulkanMemory.h
index 9956414fa9..ea0d504c61 100644
--- a/Common/Vulkan/VulkanMemory.h
+++ b/Common/Vulkan/VulkanMemory.h
@@ -130,7 +130,7 @@ private:
 
 class VulkanDeviceAllocator {
 public:
-	VulkanDeviceAllocator(VulkanContext *vulkan, size_t minSlabSize);
+	VulkanDeviceAllocator(VulkanContext *vulkan, size_t minSlabSize, size_t maxSlabSize);
 	~VulkanDeviceAllocator();
 
 	void Destroy();
@@ -183,8 +183,9 @@ private:
 	void Decimate();
 	void ExecuteFree(FreeInfo *userdata);
 
-	VulkanContext *vulkan_;
+	VulkanContext *const vulkan_;
 	std::vector<Slab> slabs_;
 	size_t minSlabSize_;
+	const size_t maxSlabSize_;
 	uint32_t memoryTypeIndex_;
 };