A part of Project Butter on B2G. To make CompositorParent being triggered by vsync notification. It may need bug 980321 to make layer update async.

WIP

WIP

WIP~ Register with info. of observer type.

Comment on attachment 8405955 [details] [diff] [review] bug-987523-fix.patch Review of attachment 8405955 [details] [diff] [review]: ----------------------------------------------------------------- ::: gfx/layers/ipc/CompositorParent.cpp @@ +95,5 @@ > +// Guarantee in Main thread > +static void CompositorRegisterVsyncObserver(CompositorParent* aCompositorParent) > +{ > + if (sCompositorParent != aCompositorParent) { > + RegisterVsyncObserver(aCompositorParent, VSYNC_TYPE_COMPOSITE); VsyncDispatcher::RegistCompositer(this) @@ +104,5 @@ > +// Guarantee in Main thread > +static void CompositorUnregisterVsyncObserver(CompositorParent* aCompositorParent) > +{ > + if (aCompositorParent != nullptr) { > + UnregisterVsyncObserver(aCompositorParent, VSYNC_TYPE_COMPOSITE); VsyncDispatcher::UnregistCompositer(this) @@ +124,5 @@ > + if (isVsyncObserver) > + sMainLoop->PostTask(FROM_HERE, NewRunnableFunction(&CompositorRegisterVsyncObserver, aCompositorParent)); > + else > + sMainLoop->PostTask(FROM_HERE, NewRunnableFunction(&CompositorUnregisterVsyncObserver, aCompositorParent)); > + } I will make sure these two functions are thread safe VsyncDispatcher::Un/RegistCompositer You don't need to handle thread issue here @@ +553,5 @@ > + // Don't schedule mCurrentCompositeTask later. Just start observing Vsync. > + if (Preferences::GetBool("hal.hw-vsync", false)) { > + CompositorIsVsyncObserver(this, true); > + return; > + } Read this pref in constructor and keep it in a data member @@ +619,5 @@ > TimeDuration minFrameDelta = TimeDuration::FromMilliseconds( > rate == 0 ? 0.0 : std::max(0.0, 1000.0 / rate)); > > + if (!Preferences::GetBool("hal.hw-vsync", false)) > + mCurrentCompositeTask = NewRunnableMethod(this, &CompositorParent::Composite); https://bugzilla.mozilla.org/show_bug.cgi?id=980241#c33 The same. You don't need to care about we use SW or HW vsync beneath. The only thing that we need to care here is whether SILK enable

Include "gfx.silk-enable" preference.

Include "gfx.silk-enable" preference.

Include "gfx.silk-enable" preference.

I would prefer not using code names in the code. Use Vsync or some such instead please.

https://bugzilla.mozilla.org/show_bug.cgi?id=980241#c37 The same reason, close this one