Bug 1929180 - Add external semaphore handling to DMABufSurface r=stransky

This is a preparation for Bug 1920763.

Add capability of importing Vulkan external semaphore to DMABufSurface(OpenGL).

Differential Revision: https://phabricator.services.mozilla.com/D227916

gfx/layers/ipc/LayersSurfaces.ipdlh

@@ -85,6 +85,7 @@ namespace layers {
   FileHandleWrapper[] fence;
   uint32_t uid;
   FileDescriptor[] refCount;
+  nullable FileHandleWrapper semaphoreFd;
 };
 
 [Comparable] struct SurfaceTextureDescriptor {

gfx/webrender_bindings/RenderDMABUFTextureHost.cpp

@@ -46,6 +46,10 @@ wr::WrExternalImage RenderDMABUFTextureHost::Lock(uint8_t aChannelIndex,
                                  mSurface->GetTexture(aChannelIndex));
   }
 
+  if (auto texture = mSurface->GetTexture(aChannelIndex)) {
+    mSurface->MaybeSemaphoreWait(texture);
+  }
+
   const gfx::IntSize size(mSurface->GetWidth(aChannelIndex),
                           mSurface->GetHeight(aChannelIndex));
   return NativeTextureToWrExternalImage(

widget/gtk/DMABufSurface.cpp

@@ -345,6 +345,50 @@ void DMABufSurface::FenceWait() {
   egl->fDestroySync(sync);
 }
 
+void DMABufSurface::MaybeSemaphoreWait(GLuint aGlTexture) {
+  MOZ_ASSERT(aGlTexture);
+
+  if (!mSemaphoreFd) {
+    return;
+  }
+
+  if (!mGL) {
+    MOZ_DIAGNOSTIC_ASSERT(mGL,
+                          "DMABufSurface::SemaphoreWait() missing GL context!");
+    return;
+  }
+
+  if (!mGL->IsExtensionSupported(gl::GLContext::EXT_semaphore) ||
+      !mGL->IsExtensionSupported(gl::GLContext::EXT_semaphore_fd)) {
+    MOZ_ASSERT_UNREACHABLE("unexpected to be called");
+    gfxCriticalNoteOnce << "EXT_semaphore_fd is not suppored";
+    return;
+  }
+
+  auto fd = mSemaphoreFd->ClonePlatformHandle();
+  // No need to try mSemaphoreFd twice.
+  mSemaphoreFd = nullptr;
+
+  GLuint semaphoreHandle = 0;
+  mGL->fGenSemaphoresEXT(1, &semaphoreHandle);
+  mGL->fImportSemaphoreFdEXT(semaphoreHandle,
+                             LOCAL_GL_HANDLE_TYPE_OPAQUE_FD_EXT, fd.release());
+  auto error = mGL->fGetError();
+  if (error != LOCAL_GL_NO_ERROR) {
+    gfxCriticalNoteOnce << "glImportSemaphoreFdEXT failed: " << error;
+    return;
+  }
+
+  GLenum srcLayout = LOCAL_GL_LAYOUT_COLOR_ATTACHMENT_EXT;
+  mGL->fWaitSemaphoreEXT(semaphoreHandle, 0, nullptr, 1, &aGlTexture,
+                         &srcLayout);
+  error = mGL->fGetError();
+  if (error != LOCAL_GL_NO_ERROR) {
+    gfxCriticalNoteOnce << "glWaitSemaphoreEXT failed: " << error;
+    return;
+  }
+}
+
 bool DMABufSurface::OpenFileDescriptors(const MutexAutoLock& aProofOfLock) {
   for (int i = 0; i < mBufferPlaneCount; i++) {
     if (!OpenFileDescriptorForPlane(aProofOfLock, i)) {
@@ -609,6 +653,10 @@ bool DMABufSurfaceRGBA::ImportSurfaceDescriptor(
     mSyncFd = new gfx::FileHandleWrapper(std::move(fd));
   }
 
+  if (desc.semaphoreFd()) {
+    mSemaphoreFd = desc.semaphoreFd();
+  }
+
   if (desc.refCount().Length() > 0) {
     GlobalRefCountImport(desc.refCount()[0].ClonePlatformHandle().release());
   }
@@ -665,7 +713,7 @@ bool DMABufSurfaceRGBA::Serialize(
   aOutDescriptor = SurfaceDescriptorDMABuf(
       mSurfaceType, modifiers, mGbmBufferFlags, fds, width, height, width,
       height, format, strides, offsets, GetYUVColorSpace(), mColorRange,
-      fenceFDs, mUID, refCountFDs);
+      fenceFDs, mUID, refCountFDs, /* semaphoreFd */ nullptr);
   return true;
 }
 
@@ -1460,7 +1508,7 @@ bool DMABufSurfaceYUV::Serialize(
   aOutDescriptor = SurfaceDescriptorDMABuf(
       mSurfaceType, modifiers, 0, fds, width, height, widthBytes, heightBytes,
       format, strides, offsets, GetYUVColorSpace(), mColorRange, fenceFDs, mUID,
-      refCountFDs);
+      refCountFDs, /* semaphoreFd */ nullptr);
   return true;
 }
 

widget/gtk/DMABufSurface.h

@@ -135,6 +135,8 @@ class DMABufSurface {
   void FenceWait();
   void FenceDelete();
 
+  void MaybeSemaphoreWait(GLuint aGlTexture);
+
   // Set and get a global surface UID. The UID is shared across process
   // and it's used to track surface lifetime in various parts of rendering
   // engine.
@@ -217,6 +219,7 @@ class DMABufSurface {
 
   RefPtr<mozilla::gfx::FileHandleWrapper> mSyncFd;
   EGLSyncKHR mSync;
+  RefPtr<mozilla::gfx::FileHandleWrapper> mSemaphoreFd;
   RefPtr<mozilla::gl::GLContext> mGL;
 
   int mGlobalRefCountFd;