Setup system in Vulkan to reuse VkDescriptorSet allocations.

src/gpu/vk/GrVkDescriptorSetManager.cpp

Index: src/gpu/vk/GrVkDescriptorSetManager.cpp
diff --git a/src/gpu/vk/GrVkDescriptorSetManager.cpp b/src/gpu/vk/GrVkDescriptorSetManager.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..29ef2fb0dd2f86fc95917ab15a9bfcfe12c21f82
--- /dev/null
+++ b/src/gpu/vk/GrVkDescriptorSetManager.cpp
@@ -0,0 +1,121 @@
+/*
+* Copyright 2016 Google Inc.
+*
+* Use of this source code is governed by a BSD-style license that can be
+* found in the LICENSE file.
+*/
+
+#include "GrVkDescriptorSetManager.h"
+
+#include "GrVkDescriptorPool.h"
+#include "GrVkDescriptorSet.h"
+#include "GrVkGpu.h"
+
+GrVkDescriptorSetManager::GrVkDescriptorSetManager(GrVkGpu* gpu,
+                                                   VkDescriptorSetLayout layout,
+                                                   VkDescriptorType type,
+                                                   uint32_t samplerCount)
+    : fPoolManager(layout, type, samplerCount, gpu)
+    , fNumSamplerBindings(samplerCount) {
+}
+
+const GrVkDescriptorSet* GrVkDescriptorSetManager::refDescriptorSet(GrVkGpu* gpu,

[jvanverth1, 2016/07/21 15:30:06]

It's not clear why this is called refDescriptorSet. Maybe getDescriptorSet?

[egdaniel, 2016/07/21 17:27:11]

Ah when I originally wrote this I was storing all the allocations so I was
actually just doing a ref here. Never changed name when I updated.

+                                                                    const Handle& handle) {
+    const GrVkDescriptorSet* ds = nullptr;
+    int count = fFreeSets.count();
+    if (count > 0) {
+        ds = fFreeSets[count - 1];
+        fFreeSets.removeShuffle(count - 1);

[jvanverth1, 2016/07/21 15:30:06]

I don't think it has to happen in this change, but we're using this pattern a
lot. I think SkTArray needs a pop_back() method.

[egdaniel, 2016/07/21 17:27:11]

Yeah I think it does actaully have a pop_back() method, but the method does not
return the variable that it pops off. Also I think remove_shuffle is better than
pop_back since pop_back does a realloc check.

+    } else {
+        VkDescriptorSet vkDS;
+        fPoolManager.getNewDescriptorSet(gpu, &vkDS);
+
+        ds = new GrVkDescriptorSet(vkDS, fPoolManager.fPool, handle);
+    }
+    SkASSERT(ds);
+    return ds;
+}
+
+void GrVkDescriptorSetManager::recycleDescriptorSet(const GrVkDescriptorSet* descSet) {
+    SkASSERT(descSet);
+    descSet->ref();

[jvanverth1, 2016/07/21 15:30:06]

I wonder if it makes sense to remove this, and the unref in
GrVkRecyclableResource::recycle.

[egdaniel, 2016/07/21 17:27:11]

Done.

+    fFreeSets.push_back(descSet);
+}
+
+void GrVkDescriptorSetManager::release(const GrVkGpu* gpu) {
+    fPoolManager.freeGPUResources(gpu);
+
+    for (int i = 0; i < fFreeSets.count(); ++i) {
+        fFreeSets[i]->unref(gpu);
+    }
+    fFreeSets.reset();
+}
+
+void GrVkDescriptorSetManager::abandon() {
+    fPoolManager.abandonGPUResources();
+
+    for (int i = 0; i < fFreeSets.count(); ++i) {
+        fFreeSets[i]->unrefAndAbandon();
+    }
+    fFreeSets.reset();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+void GrVkDescriptorSetManager::DescriptorPoolManager::getNewPool(GrVkGpu* gpu) {
+    if (fPool) {
+        fPool->unref(gpu);
+        uint32_t newPoolSize = fMaxDescriptors + ((fMaxDescriptors + 1) >> 1);
+        if (newPoolSize < kMaxDescriptors) {
+            fMaxDescriptors = newPoolSize;
+        } else {
+            fMaxDescriptors = kMaxDescriptors;
+        }
+
+    }
+    fPool = gpu->resourceProvider().findOrCreateCompatibleDescriptorPool(fDescType,
+                                                                         fMaxDescriptors);
+    SkASSERT(fPool);
+}
+
+void GrVkDescriptorSetManager::DescriptorPoolManager::getNewDescriptorSet(GrVkGpu* gpu,
+                                                                          VkDescriptorSet* ds) {
+    if (!fMaxDescriptors) {
+        return;
+    }
+    fCurrentDescriptorCount += fDescCountPerSet;
+    if (fCurrentDescriptorCount > fMaxDescriptors) {
+        this->getNewPool(gpu);
+        fCurrentDescriptorCount = fDescCountPerSet;
+    }
+
+    VkDescriptorSetAllocateInfo dsAllocateInfo;
+    memset(&dsAllocateInfo, 0, sizeof(VkDescriptorSetAllocateInfo));
+    dsAllocateInfo.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO;
+    dsAllocateInfo.pNext = nullptr;
+    dsAllocateInfo.descriptorPool = fPool->descPool();
+    dsAllocateInfo.descriptorSetCount = 1;
+    dsAllocateInfo.pSetLayouts = &fDescLayout;
+    GR_VK_CALL_ERRCHECK(gpu->vkInterface(), AllocateDescriptorSets(gpu->device(),
+                                                                   &dsAllocateInfo,
+                                                                   ds));
+}
+
+void GrVkDescriptorSetManager::DescriptorPoolManager::freeGPUResources(const GrVkGpu* gpu) {
+    // The layout should be owned by the class which owns the DescriptorSetManager so it will
+    // take care of destroying it.
+    fDescLayout = VK_NULL_HANDLE;
+
+    if (fPool) {
+        fPool->unref(gpu);
+        fPool = nullptr;
+    }
+}
+
+void GrVkDescriptorSetManager::DescriptorPoolManager::abandonGPUResources() {
+    fDescLayout = VK_NULL_HANDLE;
+    if (fPool) {
+        fPool->unrefAndAbandon();
+        fPool = nullptr;
+    }
+}