Bug 1041695 - Make ShadowLayersForwarder::RemoveTexture run on worker thread, as required by TextureClient::Finalize. r=nical

--HG--
extra : rebase_source : 5498e78ba405c0b2e75063b3d7bda7d1cead4669

gfx/layers/ipc/ShadowLayers.cpp

@@ -33,6 +33,7 @@
 #include "nsSize.h"                     // for nsIntSize
 #include "nsTArray.h"                   // for nsAutoTArray, nsTArray, etc
 #include "nsXULAppAPI.h"                // for XRE_GetProcessType, etc
+#include "mozilla/ReentrantMonitor.h"
 
 struct nsIntPoint;
 
@@ -473,11 +474,42 @@ ShadowLayerForwarder::RemoveTextureFromCompositableAsync(AsyncTransactionTracker
                                         aAsyncTransactionTracker);
 }
 
+bool
+ShadowLayerForwarder::InWorkerThread()
+{
+  return GetMessageLoop()->id() == MessageLoop::current()->id();
+}
+
+static void RemoveTextureWorker(TextureClient* aTexture, ReentrantMonitor* aBarrier, bool* aDone)
+{
+  aTexture->ForceRemove();
+
+  ReentrantMonitorAutoEnter autoMon(*aBarrier);
+  *aDone = true;
+  aBarrier->NotifyAll();
+}
+
 void
 ShadowLayerForwarder::RemoveTexture(TextureClient* aTexture)
 {
   MOZ_ASSERT(aTexture);
-  aTexture->ForceRemove();
+  if (InWorkerThread()) {
+    aTexture->ForceRemove();
+    return;
+  }
+
+  ReentrantMonitor barrier("ShadowLayerForwarder::RemoveTexture Lock");
+  ReentrantMonitorAutoEnter autoMon(barrier);
+  bool done = false;
+
+  GetMessageLoop()->PostTask(
+    FROM_HERE,
+    NewRunnableFunction(&RemoveTextureWorker, aTexture, &barrier, &done));
+
+  // Wait until the TextureClient has been ForceRemoved on the worker thread
+  while (!done) {
+    barrier.Wait();
+  }
 }
 
 bool

gfx/layers/ipc/ShadowLayers.h

@@ -393,6 +393,8 @@ protected:
   void CheckSurfaceDescriptor(const SurfaceDescriptor* aDescriptor) const {}
 #endif
 
+  bool InWorkerThread();
+
   RefPtr<LayerTransactionChild> mShadowManager;
 
 private: