replicant-frameworks_native/services/surfaceflinger/EventControlThread.cpp
Jamie Gennis d1700756ec SurfaceFlinger: Add EventControlThread
This change adds a new thread for calling HWComposer's eventControl
asynchronously.  The DispSync-based vsync approach ends up enabling and
disabling HWComposer's vsync callbacks at arbitrary times, and some HWComposer
implementations do not have these calls optimized.

Bug: 11175503
Change-Id: I719be82bd200b391c61d40863b991c7b59acdfd6
2013-10-15 14:31:41 -07:00

60 lines
1.7 KiB
C++

/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "EventControlThread.h"
#include "SurfaceFlinger.h"
namespace android {
EventControlThread::EventControlThread(const sp<SurfaceFlinger>& flinger):
mFlinger(flinger),
mVsyncEnabled(false) {
}
void EventControlThread::setVsyncEnabled(bool enabled) {
Mutex::Autolock lock(mMutex);
mVsyncEnabled = enabled;
mCond.signal();
}
bool EventControlThread::threadLoop() {
Mutex::Autolock lock(mMutex);
bool vsyncEnabled = mVsyncEnabled;
mFlinger->eventControl(HWC_DISPLAY_PRIMARY, SurfaceFlinger::EVENT_VSYNC,
mVsyncEnabled);
while (true) {
status_t err = mCond.wait(mMutex);
if (err != NO_ERROR) {
ALOGE("error waiting for new events: %s (%d)",
strerror(-err), err);
return false;
}
if (vsyncEnabled != mVsyncEnabled) {
mFlinger->eventControl(HWC_DISPLAY_PRIMARY,
SurfaceFlinger::EVENT_VSYNC, mVsyncEnabled);
vsyncEnabled = mVsyncEnabled;
}
}
return false;
}
} // namespace android