blob: fd466dedff8d43756392e4eb91ff073cec020983 [file] [log] [blame]
/*
* Copyright 2018 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 LOG_NDEBUG 0
#undef LOG_TAG
#define LOG_TAG "TransactionCompletedThread"
#define ATRACE_TAG ATRACE_TAG_GRAPHICS
#include "TransactionCompletedThread.h"
#include <cinttypes>
#include <binder/IInterface.h>
#include <gui/ITransactionCompletedListener.h>
#include <utils/RefBase.h>
namespace android {
// Returns 0 if they are equal
// <0 if the first id that doesn't match is lower in c2 or all ids match but c2 is shorter
// >0 if the first id that doesn't match is greater in c2 or all ids match but c2 is longer
//
// See CallbackIdsHash for a explaniation of why this works
static int compareCallbackIds(const std::vector<CallbackId>& c1,
const std::vector<CallbackId>& c2) {
if (c1.empty()) {
return !c2.empty();
}
return c1.front() - c2.front();
}
TransactionCompletedThread::~TransactionCompletedThread() {
std::lock_guard lockThread(mThreadMutex);
{
std::lock_guard lock(mMutex);
mKeepRunning = false;
mConditionVariable.notify_all();
}
if (mThread.joinable()) {
mThread.join();
}
{
std::lock_guard lock(mMutex);
for (const auto& [listener, transactionStats] : mCompletedTransactions) {
IInterface::asBinder(listener)->unlinkToDeath(mDeathRecipient);
}
}
}
void TransactionCompletedThread::run() {
std::lock_guard lock(mMutex);
if (mRunning || !mKeepRunning) {
return;
}
mDeathRecipient = new ThreadDeathRecipient();
mRunning = true;
std::lock_guard lockThread(mThreadMutex);
mThread = std::thread(&TransactionCompletedThread::threadMain, this);
}
status_t TransactionCompletedThread::addCallback(const sp<ITransactionCompletedListener>& listener,
const std::vector<CallbackId>& callbackIds) {
std::lock_guard lock(mMutex);
if (!mRunning) {
ALOGE("cannot add callback because the callback thread isn't running");
return BAD_VALUE;
}
if (mCompletedTransactions.count(listener) == 0) {
status_t err = IInterface::asBinder(listener)->linkToDeath(mDeathRecipient);
if (err != NO_ERROR) {
ALOGE("cannot add callback because linkToDeath failed, err: %d", err);
return err;
}
}
auto& transactionStatsDeque = mCompletedTransactions[listener];
transactionStatsDeque.emplace_back(callbackIds);
return NO_ERROR;
}
status_t TransactionCompletedThread::registerPendingCallbackHandle(
const sp<CallbackHandle>& handle) {
std::lock_guard lock(mMutex);
if (!mRunning) {
ALOGE("cannot register callback handle because the callback thread isn't running");
return BAD_VALUE;
}
// If we can't find the transaction stats something has gone wrong. The client should call
// addCallback before trying to register a pending callback handle.
TransactionStats* transactionStats;
status_t err = findTransactionStats(handle->listener, handle->callbackIds, &transactionStats);
if (err != NO_ERROR) {
ALOGE("cannot find transaction stats");
return err;
}
mPendingTransactions[handle->listener][handle->callbackIds]++;
return NO_ERROR;
}
status_t TransactionCompletedThread::addPresentedCallbackHandles(
const std::deque<sp<CallbackHandle>>& handles) {
std::lock_guard lock(mMutex);
if (!mRunning) {
ALOGE("cannot add presented callback handle because the callback thread isn't running");
return BAD_VALUE;
}
for (const auto& handle : handles) {
auto listener = mPendingTransactions.find(handle->listener);
if (listener != mPendingTransactions.end()) {
auto& pendingCallbacks = listener->second;
auto pendingCallback = pendingCallbacks.find(handle->callbackIds);
if (pendingCallback != pendingCallbacks.end()) {
auto& pendingCount = pendingCallback->second;
// Decrease the pending count for this listener
if (--pendingCount == 0) {
pendingCallbacks.erase(pendingCallback);
}
} else {
ALOGW("there are more latched callbacks than there were registered callbacks");
}
if (listener->second.size() == 0) {
mPendingTransactions.erase(listener);
}
} else {
ALOGW("cannot find listener in mPendingTransactions");
}
status_t err = addCallbackHandle(handle);
if (err != NO_ERROR) {
ALOGE("could not add callback handle");
return err;
}
}
return NO_ERROR;
}
status_t TransactionCompletedThread::addUnpresentedCallbackHandle(
const sp<CallbackHandle>& handle) {
std::lock_guard lock(mMutex);
if (!mRunning) {
ALOGE("cannot add unpresented callback handle because the callback thread isn't running");
return BAD_VALUE;
}
return addCallbackHandle(handle);
}
status_t TransactionCompletedThread::findTransactionStats(
const sp<ITransactionCompletedListener>& listener,
const std::vector<CallbackId>& callbackIds, TransactionStats** outTransactionStats) {
auto& transactionStatsDeque = mCompletedTransactions[listener];
// Search back to front because the most recent transactions are at the back of the deque
auto itr = transactionStatsDeque.rbegin();
for (; itr != transactionStatsDeque.rend(); itr++) {
if (compareCallbackIds(itr->callbackIds, callbackIds) == 0) {
*outTransactionStats = &(*itr);
return NO_ERROR;
}
}
ALOGE("could not find transaction stats");
return BAD_VALUE;
}
status_t TransactionCompletedThread::addCallbackHandle(const sp<CallbackHandle>& handle) {
// If we can't find the transaction stats something has gone wrong. The client should call
// addCallback before trying to add a presnted callback handle.
TransactionStats* transactionStats;
status_t err = findTransactionStats(handle->listener, handle->callbackIds, &transactionStats);
if (err != NO_ERROR) {
return err;
}
transactionStats->latchTime = handle->latchTime;
// If the layer has already been destroyed, don't add the SurfaceControl to the callback.
// The client side keeps a sp<> to the SurfaceControl so if the SurfaceControl has been
// destroyed the client side is dead and there won't be anyone to send the callback to.
sp<IBinder> surfaceControl = handle->surfaceControl.promote();
if (surfaceControl) {
transactionStats->surfaceStats.emplace_back(surfaceControl, handle->acquireTime,
handle->previousReleaseFence);
}
return NO_ERROR;
}
void TransactionCompletedThread::addPresentFence(const sp<Fence>& presentFence) {
std::lock_guard<std::mutex> lock(mMutex);
mPresentFence = presentFence;
}
void TransactionCompletedThread::sendCallbacks() {
std::lock_guard lock(mMutex);
if (mRunning) {
mConditionVariable.notify_all();
}
}
void TransactionCompletedThread::threadMain() {
std::lock_guard lock(mMutex);
while (mKeepRunning) {
mConditionVariable.wait(mMutex);
std::vector<ListenerStats> completedListenerStats;
// For each listener
auto completedTransactionsItr = mCompletedTransactions.begin();
while (completedTransactionsItr != mCompletedTransactions.end()) {
auto& [listener, transactionStatsDeque] = *completedTransactionsItr;
ListenerStats listenerStats;
listenerStats.listener = listener;
// For each transaction
auto transactionStatsItr = transactionStatsDeque.begin();
while (transactionStatsItr != transactionStatsDeque.end()) {
auto& transactionStats = *transactionStatsItr;
// If we are still waiting on the callback handles for this transaction, stop
// here because all transaction callbacks for the same listener must come in order
auto pendingTransactions = mPendingTransactions.find(listener);
if (pendingTransactions != mPendingTransactions.end() &&
pendingTransactions->second.count(transactionStats.callbackIds) != 0) {
break;
}
// If the transaction has been latched
if (transactionStats.latchTime >= 0) {
if (!mPresentFence) {
break;
}
transactionStats.presentFence = mPresentFence;
}
// Remove the transaction from completed to the callback
listenerStats.transactionStats.push_back(std::move(transactionStats));
transactionStatsItr = transactionStatsDeque.erase(transactionStatsItr);
}
// If the listener has completed transactions
if (!listenerStats.transactionStats.empty()) {
// If the listener is still alive
if (IInterface::asBinder(listener)->isBinderAlive()) {
// Send callback
listenerStats.listener->onTransactionCompleted(listenerStats);
IInterface::asBinder(listener)->unlinkToDeath(mDeathRecipient);
}
completedTransactionsItr = mCompletedTransactions.erase(completedTransactionsItr);
} else {
completedTransactionsItr++;
}
completedListenerStats.push_back(std::move(listenerStats));
}
if (mPresentFence) {
mPresentFence.clear();
}
// If everyone else has dropped their reference to a layer and its listener is dead,
// we are about to cause the layer to be deleted. If this happens at the wrong time and
// we are holding mMutex, we will cause a deadlock.
//
// The deadlock happens because this thread is holding on to mMutex and when we delete
// the layer, it grabs SF's mStateLock. A different SF binder thread grabs mStateLock,
// then call's TransactionCompletedThread::run() which tries to grab mMutex.
//
// To avoid this deadlock, we need to unlock mMutex when dropping our last reference to
// to the layer.
mMutex.unlock();
completedListenerStats.clear();
mMutex.lock();
}
}
// -----------------------------------------------------------------------
CallbackHandle::CallbackHandle(const sp<ITransactionCompletedListener>& transactionListener,
const std::vector<CallbackId>& ids, const sp<IBinder>& sc)
: listener(transactionListener), callbackIds(ids), surfaceControl(sc) {}
} // namespace android