Bug 1122722 - Clean up asserts for compositor threads. r=nical

gfx/layers/Compositor.cpp

@@ -22,30 +22,32 @@ namespace layers {
 /* static */ LayersBackend
 Compositor::GetBackend()
 {
-  AssertOnCompositorThread();
+  if (sBackend != LayersBackend::LAYERS_NONE) {
+    AssertOnCompositorThread();
+  }
   return sBackend;
 }
 
 /* static */ void
 Compositor::SetBackend(LayersBackend backend)
 {
-  if (!gIsGtest && sBackend != LayersBackend::LAYERS_NONE && sBackend != backend) {
+  if (!gIsGtest && sBackend != backend &&
+      sBackend != LayersBackend::LAYERS_NONE &&
+      backend != LayersBackend::LAYERS_NONE) {
     // Assert this once we figure out bug 972891.
-    //MOZ_CRASH("Trying to use more than one OMTC compositor.");
-
 #ifdef XP_MACOSX
-    printf("ERROR: Changing compositor from %u to %u.\n",
-           unsigned(sBackend), unsigned(backend));
+    gfxWarning() << "Changing compositor from " << unsigned(sBackend) << " to " << unsigned(backend);
 #endif
   }
+
   sBackend = backend;
 }
 
 /* static */ void
 Compositor::AssertOnCompositorThread()
 {
-  MOZ_ASSERT(CompositorParent::CompositorLoop() ==
-             MessageLoop::current(),
+  MOZ_ASSERT(!CompositorParent::CompositorLoop() ||
+             CompositorParent::CompositorLoop() == MessageLoop::current(),
              "Can only call this from the compositor thread!");
 }
 

gfx/layers/ipc/CompositorParent.cpp

@@ -270,6 +270,7 @@ CompositorVsyncObserver::SetNeedsComposite(bool aNeedsComposite)
     mSetNeedsCompositeTask = NewRunnableMethod(this,
                                               &CompositorVsyncObserver::SetNeedsComposite,
                                               aNeedsComposite);
+    MOZ_ASSERT(CompositorParent::CompositorLoop());
     CompositorParent::CompositorLoop()->PostTask(FROM_HERE, mSetNeedsCompositeTask);
     return;
   } else {
@@ -295,6 +296,7 @@ CompositorVsyncObserver::NotifyVsync(TimeStamp aVsyncTimestamp)
     mCurrentCompositeTask = NewRunnableMethod(this,
                                               &CompositorVsyncObserver::Composite,
                                               aVsyncTimestamp);
+    MOZ_ASSERT(CompositorParent::CompositorLoop());
     CompositorParent::CompositorLoop()->PostTask(FROM_HERE, mCurrentCompositeTask);
   }
   return true;
@@ -415,6 +417,7 @@ CompositorParent::CompositorParent(nsIWidget* aWidget,
   // FIXME: This holds on the the fact that right now the only thing that
   // can destroy this instance is initialized on the compositor thread after
   // this task has been processed.
+  MOZ_ASSERT(CompositorLoop());
   CompositorLoop()->PostTask(FROM_HERE, NewRunnableFunction(&AddCompositor,
                                                           this, &mCompositorID));
 
@@ -646,6 +649,7 @@ void
 CompositorParent::ScheduleRenderOnCompositorThread()
 {
   CancelableTask *renderTask = NewRunnableMethod(this, &CompositorParent::ScheduleComposition);
+  MOZ_ASSERT(CompositorLoop());
   CompositorLoop()->PostTask(FROM_HERE, renderTask);
 }
 
@@ -742,6 +746,7 @@ CompositorParent::SchedulePauseOnCompositorThread()
 
   CancelableTask *pauseTask = NewRunnableMethod(this,
                                                 &CompositorParent::PauseComposition);
+  MOZ_ASSERT(CompositorLoop());
   CompositorLoop()->PostTask(FROM_HERE, pauseTask);
 
   // Wait until the pause has actually been processed by the compositor thread
@@ -755,6 +760,7 @@ CompositorParent::ScheduleResumeOnCompositorThread(int width, int height)
 
   CancelableTask *resumeTask =
     NewRunnableMethod(this, &CompositorParent::ResumeCompositionAndResize, width, height);
+  MOZ_ASSERT(CompositorLoop());
   CompositorLoop()->PostTask(FROM_HERE, resumeTask);
 
   // Wait until the resume has actually been processed by the compositor thread
@@ -1329,6 +1335,7 @@ CompositorParent::DeallocateLayerTreeId(uint64_t aId)
   // Here main thread notifies compositor to remove an element from
   // sIndirectLayerTrees. This removed element might be queried soon.
   // Checking the elements of sIndirectLayerTrees exist or not before using.
+  MOZ_ASSERT(CompositorLoop());
   CompositorLoop()->PostTask(FROM_HERE,
                              NewRunnableFunction(&EraseLayerState, aId));
 }