gecko/layout/ipc/VsyncParent.cpp

113 lines
2.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "VsyncParent.h"
#include "BackgroundParent.h"
#include "BackgroundParentImpl.h"
#include "gfxPlatform.h"
#include "mozilla/unused.h"
#include "nsIThread.h"
#include "nsThreadUtils.h"
#include "VsyncSource.h"
namespace mozilla {
using namespace ipc;
namespace layout {
/*static*/ already_AddRefed<VsyncParent>
VsyncParent::Create()
{
AssertIsOnBackgroundThread();
nsRefPtr<gfx::VsyncSource> vsyncSource = gfxPlatform::GetPlatform()->GetHardwareVsync();
nsRefPtr<VsyncParent> vsyncParent = new VsyncParent();
vsyncParent->mVsyncDispatcher = vsyncSource->GetRefreshTimerVsyncDispatcher();
return vsyncParent.forget();
}
VsyncParent::VsyncParent()
: mObservingVsync(false)
, mDestroyed(false)
, mBackgroundThread(NS_GetCurrentThread())
{
MOZ_ASSERT(mBackgroundThread);
AssertIsOnBackgroundThread();
}
VsyncParent::~VsyncParent()
{
// Since we use NS_INLINE_DECL_THREADSAFE_REFCOUNTING, we can't make sure
// VsyncParent is always released on the background thread.
}
bool
VsyncParent::NotifyVsync(TimeStamp aTimeStamp)
{
// Called on hardware vsync thread. We should post to current ipc thread.
MOZ_ASSERT(!IsOnBackgroundThread());
nsRefPtr<nsIRunnable> vsyncEvent =
NS_NewRunnableMethodWithArg<TimeStamp>(this,
&VsyncParent::DispatchVsyncEvent,
aTimeStamp);
MOZ_ALWAYS_TRUE(NS_SUCCEEDED(mBackgroundThread->Dispatch(vsyncEvent, NS_DISPATCH_NORMAL)));
return true;
}
void
VsyncParent::DispatchVsyncEvent(TimeStamp aTimeStamp)
{
AssertIsOnBackgroundThread();
// If we call NotifyVsync() when we handle ActorDestroy() message, we might
// still call DispatchVsyncEvent().
// Similarly, we might also receive RecvUnobserveVsync() when call
// NotifyVsync(). We use mObservingVsync and mDestroyed flags to skip this
// notification.
if (mObservingVsync && !mDestroyed) {
unused << SendNotify(aTimeStamp);
}
}
bool
VsyncParent::RecvObserve()
{
AssertIsOnBackgroundThread();
if (!mObservingVsync) {
mVsyncDispatcher->AddChildRefreshTimer(this);
mObservingVsync = true;
return true;
}
return false;
}
bool
VsyncParent::RecvUnobserve()
{
AssertIsOnBackgroundThread();
if (mObservingVsync) {
mVsyncDispatcher->RemoveChildRefreshTimer(this);
mObservingVsync = false;
return true;
}
return false;
}
void
VsyncParent::ActorDestroy(ActorDestroyReason aReason)
{
MOZ_ASSERT(!mDestroyed);
AssertIsOnBackgroundThread();
if (mObservingVsync) {
mVsyncDispatcher->RemoveChildRefreshTimer(this);
}
mVsyncDispatcher = nullptr;
mDestroyed = true;
}
} // namespace layout
} // namespace mozilla