Bug 1288618 - Part 3: Avoid accessing MediaPrefs from the GPU process within WMF code. r=cpearce

--HG--
extra : rebase_source : 8c8d88ed1b858d59555e2c698f7faf653c8a75e6

dom/media/platforms/wmf/DXVA2Manager.cpp

@@ -494,7 +494,12 @@ DXVA2Manager::CreateD3D9DXVA(nsACString& aFailureReason)
 
   // DXVA processing takes up a lot of GPU resources, so limit the number of
   // videos we use DXVA with at any one time.
-  const uint32_t dxvaLimit = MediaPrefs::PDMWMFMaxDXVAVideos();
+  uint32_t dxvaLimit = 4;
+  // TODO: Sync this value across to the GPU process.
+  if (XRE_GetProcessType() != GeckoProcessType_GPU) {
+    dxvaLimit = MediaPrefs::PDMWMFMaxDXVAVideos();
+  }
+
   if (sDXVAVideosCount == dxvaLimit) {
     aFailureReason.AssignLiteral("Too many DXVA videos playing");
     return nullptr;
@@ -902,7 +907,12 @@ DXVA2Manager::CreateD3D11DXVA(nsACString& aFailureReason)
 {
   // DXVA processing takes up a lot of GPU resources, so limit the number of
   // videos we use DXVA with at any one time.
-  const uint32_t dxvaLimit = MediaPrefs::PDMWMFMaxDXVAVideos();
+  uint32_t dxvaLimit = 4;
+  // TODO: Sync this value across to the GPU process.
+  if (XRE_GetProcessType() != GeckoProcessType_GPU) {
+    dxvaLimit = MediaPrefs::PDMWMFMaxDXVAVideos();
+  }
+
   if (sDXVAVideosCount == dxvaLimit) {
     aFailureReason.AssignLiteral("Too many DXVA videos playing");
     return nullptr;

dom/media/platforms/wmf/WMFDecoderModule.cpp

@@ -61,7 +61,10 @@ WMFDecoderModule::GetNumDecoderThreads()
   // If we have more than 4 cores, let the decoder decide how many threads.
   // On an 8 core machine, WMF chooses 4 decoder threads
   const int WMF_DECODER_DEFAULT = -1;
-  int32_t prefThreadCount = MediaPrefs::PDMWMFThreadCount();
+  int32_t prefThreadCount = WMF_DECODER_DEFAULT;
+  if (XRE_GetProcessType() != GeckoProcessType_GPU) {
+    prefThreadCount = MediaPrefs::PDMWMFThreadCount();
+  }
   if (prefThreadCount != WMF_DECODER_DEFAULT) {
     return std::max(prefThreadCount, 1);
   } else if (numCores > 4) {

dom/media/platforms/wmf/WMFVideoMFTManager.cpp

@@ -180,6 +180,14 @@ FindDXVABlacklistedDLL(StaticAutoPtr<D3DDLLBlacklistingCache>& aDLLBlacklistingC
     ClearOnShutdown(&aDLLBlacklistingCache);
   }
 
+  if (XRE_GetProcessType() == GeckoProcessType_GPU) {
+    // The blacklist code doesn't support running in
+    // the GPU process yet.
+    aDLLBlacklistingCache->mBlacklistPref.SetLength(0);
+    aDLLBlacklistingCache->mBlacklistedDLL.SetLength(0);
+    return aDLLBlacklistingCache->mBlacklistedDLL;
+  }
+
   nsAdoptingCString blacklist = Preferences::GetCString(aDLLBlacklistPrefName);
   if (blacklist.IsEmpty()) {
     // Empty blacklist -> No blacklisting.
@@ -304,8 +312,10 @@ public:
     NS_ASSERTION(NS_IsMainThread(), "Must be on main thread.");
     nsACString* failureReason = &mFailureReason;
     nsCString secondFailureReason;
+    bool allowD3D11 = (XRE_GetProcessType() == GeckoProcessType_GPU) ||
+                      MediaPrefs::PDMWMFAllowD3D11();
     if (mBackend == LayersBackend::LAYERS_D3D11 &&
-        MediaPrefs::PDMWMFAllowD3D11() && IsWin8OrLater()) {
+        allowD3D11 && IsWin8OrLater()) {
       const nsCString& blacklistedDLL = FindD3D11BlacklistedDLL();
       if (!blacklistedDLL.IsEmpty()) {
         failureReason->AppendPrintf("D3D11 blacklisted with DLL %s",
@@ -431,7 +441,8 @@ WMFVideoMFTManager::InitInternal(bool aForceD3D9)
     attr->GetUINT32(MF_SA_D3D_AWARE, &aware);
     attr->SetUINT32(CODECAPI_AVDecNumWorkerThreads,
       WMFDecoderModule::GetNumDecoderThreads());
-    if (MediaPrefs::PDMWMFLowLatencyEnabled()) {
+    if ((XRE_GetProcessType() != GeckoProcessType_GPU) &&
+        MediaPrefs::PDMWMFLowLatencyEnabled()) {
       hr = attr->SetUINT32(CODECAPI_AVLowLatencyMode, TRUE);
       if (SUCCEEDED(hr)) {
         LOG("Enabling Low Latency Mode");