Giovanni Mascellani : dxgi: Introduce a worker thread for the D3D12 swapchain.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: f07859d75b39164f92b78ead7828c28924fe5c7e
URL:    https://gitlab.winehq.org/wine/wine/-/commit/f07859d75b39164f92b78ead7828c28...

Author: Giovanni Mascellani 
Date:   Thu Jun 22 11:03:42 2023 +0200

dxgi: Introduce a worker thread for the D3D12 swapchain.

In the following commits the worker thread will be used for actual
presenting and buffer resizing. In this way the worker thread can
wait on the vkd3d queue without blocking or even deadlocking the
application.

---

dlls/dxgi/swapchain.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/dlls/dxgi/swapchain.c b/dlls/dxgi/swapchain.c
index 34678a3a3a7..8a84ea30065 100644
--- a/dlls/dxgi/swapchain.c
+++ b/dlls/dxgi/swapchain.c
@@ -1024,6 +1024,11 @@ struct d3d12_swapchain
     VkDevice vk_device;
     VkPhysicalDevice vk_physical_device;

+    HANDLE worker_thread;
+    CRITICAL_SECTION worker_cs;
+    CONDITION_VARIABLE worker_cv;
+    bool worker_running;
+
     /* D3D12 side of the swapchain (frontend): these objects are
      * visible to the IDXGISwapChain client, so they must never be
      * recreated, except when ResizeBuffers*() is called. */
@@ -1070,6 +1075,26 @@ struct d3d12_swapchain
     uint32_t frame_latency;
 };

+static DWORD WINAPI d3d12_swapchain_worker_proc(void *data)
+{
+    struct d3d12_swapchain *swapchain = data;
+
+    EnterCriticalSection(&swapchain->worker_cs);
+
+    while (swapchain->worker_running)
+    {
+        if (!SleepConditionVariableCS(&swapchain->worker_cv, &swapchain->worker_cs, INFINITE))
+        {
+            ERR("Cannot sleep on condition variable, last error %ld.\n", GetLastError());
+            break;
+        }
+    }
+
+    LeaveCriticalSection(&swapchain->worker_cs);
+
+    return 0;
+}
+
 static DXGI_FORMAT dxgi_format_from_vk_format(VkFormat vk_format)
 {
     switch (vk_format)
@@ -1808,6 +1833,23 @@ static void d3d12_swapchain_destroy(struct d3d12_swapchain *swapchain)
 {
     const struct dxgi_vk_funcs *vk_funcs = &swapchain->vk_funcs;
     void *vulkan_module = vk_funcs->vulkan_module;
+    DWORD ret;
+
+    EnterCriticalSection(&swapchain->worker_cs);
+    swapchain->worker_running = false;
+    WakeAllConditionVariable(&swapchain->worker_cv);
+    LeaveCriticalSection(&swapchain->worker_cs);
+
+    if (swapchain->worker_thread)
+    {
+        if ((ret = WaitForSingleObject(swapchain->worker_thread, INFINITE)) != WAIT_OBJECT_0)
+            ERR("Failed to wait for worker thread, return value %ld.\n", ret);
+
+        if (!CloseHandle(swapchain->worker_thread))
+            ERR("Failed to close worker thread, last error %ld.\n", GetLastError());
+    }
+
+    DeleteCriticalSection(&swapchain->worker_cs);

d3d12_swapchain_destroy_vulkan_resources(swapchain);
     d3d12_swapchain_destroy_d3d12_resources(swapchain);
@@ -2996,6 +3038,10 @@ static HRESULT d3d12_swapchain_init(struct d3d12_swapchain *swapchain, IWineDXGI

wined3d_private_store_init(&swapchain->private_store);

+    InitializeCriticalSection(&swapchain->worker_cs);
+    InitializeConditionVariable(&swapchain->worker_cv);
+    swapchain->worker_running = true;
+
     surface_desc.sType = VK_STRUCTURE_TYPE_WIN32_SURFACE_CREATE_INFO_KHR;
     surface_desc.pNext = NULL;
     surface_desc.flags = 0;
@@ -3069,6 +3115,14 @@ static HRESULT d3d12_swapchain_init(struct d3d12_swapchain *swapchain, IWineDXGI

IWineDXGIFactory_AddRef(swapchain->factory = factory);

+    if (!(swapchain->worker_thread = CreateThread(NULL, 0, d3d12_swapchain_worker_proc, swapchain, 0, NULL)))
+    {
+        hr = HRESULT_FROM_WIN32(GetLastError());
+        WARN("Failed to create worker thread, hr %#lx.\n", hr);
+        d3d12_swapchain_destroy(swapchain);
+        return hr;
+    }
+
     return S_OK;
 }