From c3a721f562b590b8d301d9d7a2a4e989928f1eeb Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Mon, 22 Aug 2022 14:05:29 +0200
Subject: [PATCH] [dxvk] Introduce DxvkCommandPool

---
 src/dxvk/dxvk_cmdlist.cpp | 65 +++++++++++++++++++++++++++++++++++++++
 src/dxvk/dxvk_cmdlist.h   | 46 ++++++++++++++++++++++++++-
 2 files changed, 110 insertions(+), 1 deletion(-)

diff --git a/src/dxvk/dxvk_cmdlist.cpp b/src/dxvk/dxvk_cmdlist.cpp
index cc5af6ca3..cd3a1be62 100644
--- a/src/dxvk/dxvk_cmdlist.cpp
+++ b/src/dxvk/dxvk_cmdlist.cpp
@@ -87,6 +87,71 @@ namespace dxvk {
   }
 
 
+  DxvkCommandPool::DxvkCommandPool(
+          DxvkDevice*           device,
+          uint32_t              queueFamily)
+  : m_device(device) {
+    auto vk = m_device->vkd();
+
+    VkCommandPoolCreateInfo poolInfo = { VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO };
+    poolInfo.queueFamilyIndex = queueFamily;
+
+    if (vk->vkCreateCommandPool(vk->device(), &poolInfo, nullptr, &m_commandPool))
+      throw DxvkError("DxvkCommandPool: Failed to create command pool");
+  }
+
+
+  DxvkCommandPool::~DxvkCommandPool() {
+    auto vk = m_device->vkd();
+
+    vk->vkDestroyCommandPool(vk->device(), m_commandPool, nullptr);
+  }
+
+
+  VkCommandBuffer DxvkCommandPool::getCommandBuffer() {
+    auto vk = m_device->vkd();
+
+    if (m_next == m_commandBuffers.size()) {
+      // Allocate a new command buffer and add it to the list
+      VkCommandBufferAllocateInfo allocInfo = { VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO };
+      allocInfo.commandPool = m_commandPool;
+      allocInfo.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY;
+      allocInfo.commandBufferCount = 1;
+
+      VkCommandBuffer commandBuffer = VK_NULL_HANDLE;
+
+      if (vk->vkAllocateCommandBuffers(vk->device(), &allocInfo, &commandBuffer))
+        throw DxvkError("DxvkCommandPool: Failed to allocate command buffer");
+
+      m_commandBuffers.push_back(commandBuffer);
+    }
+
+    // Take existing command buffer. All command buffers
+    // will be in reset state, so we can begin it safely.
+    VkCommandBuffer commandBuffer = m_commandBuffers[m_next++];
+
+    VkCommandBufferBeginInfo info = { VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO };
+    info.flags = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+
+    if (vk->vkBeginCommandBuffer(commandBuffer, &info))
+      throw DxvkError("DxvkCommandPool: Failed to begin command buffer");
+
+    return commandBuffer;
+  }
+
+
+  void DxvkCommandPool::reset() {
+    auto vk = m_device->vkd();
+
+    if (m_next) {
+      if (vk->vkResetCommandPool(vk->device(), m_commandPool, 0))
+        throw DxvkError("DxvkCommandPool: Failed to reset command pool");
+
+      m_next = 0;
+    }
+  }
+
+
   DxvkCommandList::DxvkCommandList(DxvkDevice* device)
   : m_device        (device),
     m_vkd           (device->vkd()),
diff --git a/src/dxvk/dxvk_cmdlist.h b/src/dxvk/dxvk_cmdlist.h
index 25bd59127..9d1487474 100644
--- a/src/dxvk/dxvk_cmdlist.h
+++ b/src/dxvk/dxvk_cmdlist.h
@@ -118,7 +118,51 @@ namespace dxvk {
 
 
   /**
-   * \brief DXVK command list
+   * \brief Command pool
+   *
+   * Simple command pool abstraction that allows
+   * us to easily obtain command buffers.
+   */
+  class DxvkCommandPool : public RcObject {
+
+  public:
+
+    /**
+     * \brief Creates command pool
+     *
+     * \param [in] device DXVK device
+     * \param [in] queueFamily Target queue family
+     */
+    DxvkCommandPool(
+            DxvkDevice*           device,
+            uint32_t              queueFamily);
+
+    ~DxvkCommandPool();
+
+    /**
+     * \brief Retrieves or allocates a command buffer
+     * \returns New command buffer in begun state
+     */
+    VkCommandBuffer getCommandBuffer();
+
+    /**
+     * \brief Resets command pool and all command buffers
+     */
+    void reset();
+
+  private:
+
+    DxvkDevice*                   m_device;
+
+    VkCommandPool                 m_commandPool = VK_NULL_HANDLE;
+    std::vector<VkCommandBuffer>  m_commandBuffers;
+    size_t                        m_next        = 0;
+
+  };
+
+
+  /**
+   * \brief Command list
    * 
    * Stores a command buffer that a context can use to record Vulkan
    * commands. The command list shall also reference the resources