replicant-frameworks_native/services/surfaceflinger/EventThread.cpp
Mathias Agopian cb9732a951 refactor / simplify EventThread
Change-Id: I3981c6fba93b7b985174b2a7045e24db2c0b4428
2012-04-03 18:28:25 -07:00

261 lines
8.5 KiB
C++

/*
* Copyright (C) 2011 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.
*/
#define ATRACE_TAG ATRACE_TAG_GRAPHICS
#include <stdint.h>
#include <sys/types.h>
#include <gui/BitTube.h>
#include <gui/IDisplayEventConnection.h>
#include <gui/DisplayEventReceiver.h>
#include <utils/Errors.h>
#include <utils/Trace.h>
#include "DisplayHardware/DisplayHardware.h"
#include "EventThread.h"
#include "SurfaceFlinger.h"
// ---------------------------------------------------------------------------
namespace android {
// ---------------------------------------------------------------------------
EventThread::EventThread(const sp<SurfaceFlinger>& flinger)
: mFlinger(flinger),
mHw(flinger->graphicPlane(0).displayHardware()),
mLastVSyncTimestamp(0),
mDeliveredEvents(0)
{
}
void EventThread::onFirstRef() {
run("EventThread", PRIORITY_URGENT_DISPLAY + PRIORITY_MORE_FAVORABLE);
}
sp<EventThread::Connection> EventThread::createEventConnection() const {
return new Connection(const_cast<EventThread*>(this));
}
nsecs_t EventThread::getLastVSyncTimestamp() const {
Mutex::Autolock _l(mLock);
return mLastVSyncTimestamp;
}
nsecs_t EventThread::getVSyncPeriod() const {
return mHw.getRefreshPeriod();
}
status_t EventThread::registerDisplayEventConnection(
const sp<EventThread::Connection>& connection) {
Mutex::Autolock _l(mLock);
mDisplayEventConnections.add(connection);
mCondition.signal();
return NO_ERROR;
}
status_t EventThread::unregisterDisplayEventConnection(
const wp<EventThread::Connection>& connection) {
Mutex::Autolock _l(mLock);
mDisplayEventConnections.remove(connection);
mCondition.signal();
return NO_ERROR;
}
void EventThread::removeDisplayEventConnection(
const wp<EventThread::Connection>& connection) {
Mutex::Autolock _l(mLock);
mDisplayEventConnections.remove(connection);
}
void EventThread::setVsyncRate(uint32_t count,
const sp<EventThread::Connection>& connection) {
if (int32_t(count) >= 0) { // server must protect against bad params
Mutex::Autolock _l(mLock);
const int32_t new_count = (count == 0) ? -1 : count;
if (connection->count != new_count) {
connection->count = new_count;
mCondition.signal();
}
}
}
void EventThread::requestNextVsync(
const sp<EventThread::Connection>& connection) {
Mutex::Autolock _l(mLock);
if (connection->count < 0) {
connection->count = 0;
mCondition.signal();
}
}
bool EventThread::threadLoop() {
nsecs_t timestamp;
DisplayEventReceiver::Event vsync;
Vector< wp<EventThread::Connection> > displayEventConnections;
{ // scope for the lock
Mutex::Autolock _l(mLock);
do {
// see if we need to wait for the VSYNC at all
do {
bool waitForNextVsync = false;
size_t count = mDisplayEventConnections.size();
for (size_t i=0 ; i<count ; i++) {
sp<Connection> connection =
mDisplayEventConnections.itemAt(i).promote();
if (connection!=0 && connection->count >= 0) {
// at least one continuous mode or active one-shot event
waitForNextVsync = true;
break;
}
}
if (waitForNextVsync)
break;
mCondition.wait(mLock);
} while(true);
// at least one listener requested VSYNC
mLock.unlock();
timestamp = mHw.waitForRefresh();
ATRACE_INT("VSYNC", mDeliveredEvents&1);
mLock.lock();
mDeliveredEvents++;
mLastVSyncTimestamp = timestamp;
// now see if we still need to report this VSYNC event
const size_t count = mDisplayEventConnections.size();
for (size_t i=0 ; i<count ; i++) {
bool reportVsync = false;
sp<Connection> connection =
mDisplayEventConnections.itemAt(i).promote();
if (connection == 0)
continue;
const int32_t count = connection->count;
if (count >= 1) {
if (count==1 || (mDeliveredEvents % count) == 0) {
// continuous event, and time to report it
reportVsync = true;
}
} else if (count >= -1) {
if (count == 0) {
// fired this time around
reportVsync = true;
}
connection->count--;
}
if (reportVsync) {
displayEventConnections.add(connection);
}
}
} while (!displayEventConnections.size());
// dispatch vsync events to listeners...
vsync.header.type = DisplayEventReceiver::DISPLAY_EVENT_VSYNC;
vsync.header.timestamp = timestamp;
vsync.vsync.count = mDeliveredEvents;
}
const size_t count = displayEventConnections.size();
for (size_t i=0 ; i<count ; i++) {
sp<Connection> conn(displayEventConnections[i].promote());
// make sure the connection didn't die
if (conn != NULL) {
status_t err = conn->postEvent(vsync);
if (err == -EAGAIN || err == -EWOULDBLOCK) {
// The destination doesn't accept events anymore, it's probably
// full. For now, we just drop the events on the floor.
// Note that some events cannot be dropped and would have to be
// re-sent later. Right-now we don't have the ability to do
// this, but it doesn't matter for VSYNC.
} else if (err < 0) {
// handle any other error on the pipe as fatal. the only
// reasonable thing to do is to clean-up this connection.
// The most common error we'll get here is -EPIPE.
removeDisplayEventConnection(displayEventConnections[i]);
}
} else {
// somehow the connection is dead, but we still have it in our list
// just clean the list.
removeDisplayEventConnection(displayEventConnections[i]);
}
}
// clear all our references without holding mLock
displayEventConnections.clear();
return true;
}
status_t EventThread::readyToRun() {
ALOGI("EventThread ready to run.");
return NO_ERROR;
}
void EventThread::dump(String8& result, char* buffer, size_t SIZE) const {
Mutex::Autolock _l(mLock);
result.append("VSYNC state:\n");
snprintf(buffer, SIZE, " numListeners=%u, events-delivered: %u\n",
mDisplayEventConnections.size(), mDeliveredEvents);
result.append(buffer);
}
// ---------------------------------------------------------------------------
EventThread::Connection::Connection(
const sp<EventThread>& eventThread)
: count(-1), mEventThread(eventThread), mChannel(new BitTube())
{
}
EventThread::Connection::~Connection() {
mEventThread->unregisterDisplayEventConnection(this);
}
void EventThread::Connection::onFirstRef() {
// NOTE: mEventThread doesn't hold a strong reference on us
mEventThread->registerDisplayEventConnection(this);
}
sp<BitTube> EventThread::Connection::getDataChannel() const {
return mChannel;
}
void EventThread::Connection::setVsyncRate(uint32_t count) {
mEventThread->setVsyncRate(count, this);
}
void EventThread::Connection::requestNextVsync() {
mEventThread->requestNextVsync(this);
}
status_t EventThread::Connection::postEvent(
const DisplayEventReceiver::Event& event) {
ssize_t size = DisplayEventReceiver::sendEvents(mChannel, &event, 1);
return size < 0 ? status_t(size) : status_t(NO_ERROR);
}
// ---------------------------------------------------------------------------
}; // namespace android