d3d11: Enable native multi-thread protection layer and make use of it

... instead of our own GRecMutex locking. In this way, any other
Direct3D11 client (MediaFoundation for example) can safely call
any Direct3D11 API even when we are sharing our Direct3D11 device
with others.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2092>

3 files changed, 24 insertions, 17 deletions

diff --git a/gst-libs/gst/d3d11/gstd3d11device.c b/gst-libs/gst/d3d11/gstd3d11device.c
index fd40ead5e..337bc19ce 100644
--- a/gst-libs/gst/d3d11/gstd3d11device.c
+++ b/gst-libs/gst/d3d11/gstd3d11device.c
@@ -30,6 +30,7 @@
 
 #include <windows.h>
 #include <versionhelpers.h>
+#include <d3d10.h>
 
 /**
  * SECTION:gstd3d11device
@@ -105,11 +106,11 @@ struct _GstD3D11DevicePrivate
 
   ID3D11VideoDevice *video_device;
   ID3D11VideoContext *video_context;
+  ID3D10Multithread *multi_thread;
 
   IDXGIFactory1 *factory;
   GstD3D11Format format_table[GST_D3D11_N_FORMATS];
 
-  GRecMutex extern_lock;
   GMutex resource_lock;
 
 #if HAVE_D3D11SDKLAYERS_H
@@ -412,7 +413,6 @@ gst_d3d11_device_init (GstD3D11Device * self)
   priv = gst_d3d11_device_get_instance_private (self);
   priv->adapter = DEFAULT_ADAPTER;
 
-  g_rec_mutex_init (&priv->extern_lock);
   g_mutex_init (&priv->resource_lock);
 
   self->priv = priv;
@@ -784,6 +784,20 @@ gst_d3d11_device_constructed (GObject * object)
     goto error;
   }
 
+  hr = ID3D11Device_QueryInterface (priv->device, &IID_ID3D10Multithread,
+      (void **) &priv->multi_thread);
+  if (!gst_d3d11_result (hr, NULL)) {
+    GST_ERROR_OBJECT (self, "ID3D10Multithread interface is not available");
+    ID3D11Device_Release (priv->device);
+    priv->device = NULL;
+
+    ID3D11DeviceContext_Release (priv->device_context);
+    priv->device_context = NULL;
+    goto error;
+  }
+
+  ID3D10Multithread_SetMultithreadProtected (priv->multi_thread, TRUE);
+
   priv->factory = factory;
 
 #if HAVE_D3D11SDKLAYERS_H
@@ -899,6 +913,11 @@ gst_d3d11_device_dispose (GObject * object)
 
   GST_LOG_OBJECT (self, "dispose");
 
+  if (priv->multi_thread) {
+    ID3D10Multithread_Release (priv->multi_thread);
+    priv->multi_thread = NULL;
+  }
+
   if (priv->video_device) {
     ID3D11VideoDevice_Release (priv->video_device);
     priv->video_device = NULL;
@@ -966,7 +985,6 @@ gst_d3d11_device_finalize (GObject * object)
 
   GST_LOG_OBJECT (self, "finalize");
 
-  g_rec_mutex_clear (&priv->extern_lock);
   g_mutex_clear (&priv->resource_lock);
   g_free (priv->description);
 
@@ -1148,7 +1166,7 @@ gst_d3d11_device_lock (GstD3D11Device * device)
   priv = device->priv;
 
   GST_TRACE_OBJECT (device, "device locking");
-  g_rec_mutex_lock (&priv->extern_lock);
+  ID3D10Multithread_Enter (priv->multi_thread);
   GST_TRACE_OBJECT (device, "device locked");
 }
 
@@ -1169,8 +1187,8 @@ gst_d3d11_device_unlock (GstD3D11Device * device)
   g_return_if_fail (GST_IS_D3D11_DEVICE (device));
 
   priv = device->priv;
+  ID3D10Multithread_Leave (priv->multi_thread);
 
-  g_rec_mutex_unlock (&priv->extern_lock);
   GST_TRACE_OBJECT (device, "device unlocked");
 }
 
diff --git a/gst-libs/gst/d3d11/gstd3d11memory.c b/gst-libs/gst/d3d11/gstd3d11memory.c
index 0c96d7f31..da32c9e07 100644
--- a/gst-libs/gst/d3d11/gstd3d11memory.c
+++ b/gst-libs/gst/d3d11/gstd3d11memory.c
@@ -347,7 +347,6 @@ map_cpu_access_data (GstD3D11Memory * dmem, D3D11_MAP map_type)
   ID3D11DeviceContext *device_context =
       gst_d3d11_device_get_device_context_handle (dmem->device);
 
-  gst_d3d11_device_lock (dmem->device);
   if (GST_MEMORY_FLAG_IS_SET (dmem, GST_D3D11_MEMORY_TRANSFER_NEED_DOWNLOAD)) {
     ID3D11DeviceContext_CopySubresourceRegion (device_context,
         staging, 0, 0, 0, 0, texture, priv->subresource_index, NULL);
@@ -362,8 +361,6 @@ map_cpu_access_data (GstD3D11Memory * dmem, D3D11_MAP map_type)
     ret = FALSE;
   }
 
-  gst_d3d11_device_unlock (dmem->device);
-
   return ret;
 }
 
@@ -383,7 +380,6 @@ gst_d3d11_memory_map_staging (GstMemory * mem, GstMapFlags flags)
 
     map_type = gst_map_flags_to_d3d11 (flags);
 
-    gst_d3d11_device_lock (dmem->device);
     hr = ID3D11DeviceContext_Map (device_context,
         (ID3D11Resource *) priv->texture, 0, map_type, 0, &priv->map);
     if (!gst_d3d11_result (hr, dmem->device)) {
@@ -391,7 +387,6 @@ gst_d3d11_memory_map_staging (GstMemory * mem, GstMapFlags flags)
           "Failed to map staging texture (0x%x)", (guint) hr);
       ret = FALSE;
     }
-    gst_d3d11_device_unlock (dmem->device);
 
     if (!ret) {
       GST_D3D11_MEMORY_UNLOCK (dmem);
@@ -425,11 +420,9 @@ gst_d3d11_memory_map (GstMemory * mem, gsize maxsize, GstMapFlags flags)
       ID3D11DeviceContext *device_context =
           gst_d3d11_device_get_device_context_handle (dmem->device);
 
-      gst_d3d11_device_lock (dmem->device);
       ID3D11DeviceContext_CopySubresourceRegion (device_context,
           (ID3D11Resource *) priv->texture, priv->subresource_index, 0, 0, 0,
           (ID3D11Resource *) priv->staging, 0, NULL);
-      gst_d3d11_device_unlock (dmem->device);
     }
 
     GST_MEMORY_FLAG_UNSET (dmem, GST_D3D11_MEMORY_TRANSFER_NEED_UPLOAD);
@@ -492,9 +485,7 @@ unmap_cpu_access_data (GstD3D11Memory * dmem)
   if (priv->type == GST_D3D11_MEMORY_TYPE_STAGING)
     staging = (ID3D11Resource *) priv->texture;
 
-  gst_d3d11_device_lock (dmem->device);
   ID3D11DeviceContext_Unmap (device_context, staging, 0);
-  gst_d3d11_device_unlock (dmem->device);
 }
 
 static void
@@ -693,7 +684,6 @@ calculate_mem_size (GstD3D11Device * device, ID3D11Texture2D * texture,
   ID3D11DeviceContext *device_context =
       gst_d3d11_device_get_device_context_handle (device);
 
-  gst_d3d11_device_lock (device);
   hr = ID3D11DeviceContext_Map (device_context,
       (ID3D11Resource *) texture, 0, map_type, 0, &map);
 
@@ -707,7 +697,6 @@ calculate_mem_size (GstD3D11Device * device, ID3D11Texture2D * texture,
       desc->Width, desc->Height, map.RowPitch, offset, stride, size);
 
   ID3D11DeviceContext_Unmap (device_context, (ID3D11Resource *) texture, 0);
-  gst_d3d11_device_unlock (device);
 
   return ret;
 }
diff --git a/gst-libs/gst/d3d11/meson.build b/gst-libs/gst/d3d11/meson.build
index b699082d5..b0b2ae9cf 100644
--- a/gst-libs/gst/d3d11/meson.build
+++ b/gst-libs/gst/d3d11/meson.build
@@ -72,7 +72,7 @@ foreach d3d11_h: d3d11_headers
   endif
 endforeach
 
-have_d3d11 = d3d11_lib.found() and dxgi_lib.found() and have_d3d11_header and have_dxgi_header
+have_d3d11 = d3d11_lib.found() and dxgi_lib.found() and have_d3d11_header and have_dxgi_header and cc.has_header('d3d10.h')
 if not have_d3d11
   if d3d11_option.enabled()
     error('The d3d11 was enabled explicitly, but required dependencies were not found.')