From 7c9fa270062a2ea0f9aacdf17835231e8878bc41 Mon Sep 17 00:00:00 2001 From: Patrick Williams Date: Fri, 30 Aug 2024 12:38:43 +0000 Subject: Read from BufferReleaseChannel in background thread Bug: 294133380 Flag: com.android.graphics.libgui.flags.buffer_release_channel Test: BLASTBufferQueueTest Change-Id: I99c5da3bd99d6893ae24f5d55e7553b02bfc07ab --- libs/gui/BLASTBufferQueue.cpp | 161 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 151 insertions(+), 10 deletions(-) (limited to 'libs/gui/BLASTBufferQueue.cpp') diff --git a/libs/gui/BLASTBufferQueue.cpp b/libs/gui/BLASTBufferQueue.cpp index b8d2b5ffbf..3c1971fd81 100644 --- a/libs/gui/BLASTBufferQueue.cpp +++ b/libs/gui/BLASTBufferQueue.cpp @@ -22,11 +22,14 @@ #include #include +#include #include #include #include #include #include +#include +#include #include #include @@ -74,6 +77,12 @@ namespace android { std::unique_lock _lock{mutex}; \ base::ScopedLockAssertion assumeLocked(mutex); +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) +static ReleaseBufferCallback EMPTY_RELEASE_CALLBACK = + [](const ReleaseCallbackId&, const sp& /*releaseFence*/, + std::optional /*currentMaxAcquiredBufferCount*/) {}; +#endif + void BLASTBufferItemConsumer::onDisconnect() { Mutex::Autolock lock(mMutex); mPreviouslyConnected = mCurrentlyConnected; @@ -215,6 +224,12 @@ BLASTBufferQueue::BLASTBufferQueue(const std::string& name, bool updateDestinati }, this); +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) + std::unique_ptr bufferReleaseConsumer; + gui::BufferReleaseChannel::open(mName, bufferReleaseConsumer, mBufferReleaseProducer); + mBufferReleaseReader = std::make_shared(std::move(bufferReleaseConsumer)); +#endif + BQA_LOGV("BLASTBufferQueue created"); } @@ -244,6 +259,9 @@ BLASTBufferQueue::~BLASTBufferQueue() { void BLASTBufferQueue::onFirstRef() { // safe default, most producers are expected to override this mProducer->setMaxDequeuedBufferCount(2); +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) + mBufferReleaseThread.start(sp::fromExisting(this)); +#endif } void BLASTBufferQueue::update(const sp& surface, uint32_t width, uint32_t height, @@ -269,6 +287,9 @@ void BLASTBufferQueue::update(const sp& surface, uint32_t width, if (surfaceControlChanged) { t.setFlags(mSurfaceControl, layer_state_t::eEnableBackpressure, layer_state_t::eEnableBackpressure); +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) + t.setBufferReleaseChannel(mSurfaceControl, mBufferReleaseProducer); +#endif applyTransaction = true; } mTransformHint = mSurfaceControl->getTransformHint(); @@ -386,6 +407,7 @@ void BLASTBufferQueue::transactionCallback(nsecs_t /*latchTime*/, const sp staleReleases; for (const auto& [key, value]: mSubmitted) { @@ -401,6 +423,7 @@ void BLASTBufferQueue::transactionCallback(nsecs_t /*latchTime*/, const sp 0) { + acquireNextBufferLocked(std::nullopt); + numFramesToFlush--; + } +} + // Unlike transactionCallbackThunk the release buffer callback does not extend the life of the // BBQ. This is because if the BBQ is destroyed, then the buffers will be released by the client. // So we pass in a weak pointer to the BBQ and if it still alive, then we release the buffer. @@ -428,15 +460,6 @@ ReleaseBufferCallback BLASTBufferQueue::makeReleaseBufferCallbackThunk() { }; } -void BLASTBufferQueue::flushShadowQueue() { - BQA_LOGV("flushShadowQueue"); - int numFramesToFlush = mNumFrameAvailable; - while (numFramesToFlush > 0) { - acquireNextBufferLocked(std::nullopt); - numFramesToFlush--; - } -} - void BLASTBufferQueue::releaseBufferCallback( const ReleaseCallbackId& id, const sp& releaseFence, std::optional currentMaxAcquiredBufferCount) { @@ -611,7 +634,12 @@ status_t BLASTBufferQueue::acquireNextBufferLocked( bufferItem.mGraphicBuffer->getHeight(), bufferItem.mTransform, bufferItem.mScalingMode, crop); +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) + ReleaseBufferCallback releaseBufferCallback = + applyTransaction ? EMPTY_RELEASE_CALLBACK : makeReleaseBufferCallbackThunk(); +#else auto releaseBufferCallback = makeReleaseBufferCallbackThunk(); +#endif sp fence = bufferItem.mFence ? new Fence(bufferItem.mFence->dup()) : Fence::NO_FENCE; nsecs_t dequeueTime = -1; @@ -1224,7 +1252,120 @@ bool BLASTBufferQueue::isSameSurfaceControl(const sp& surfaceCon void BLASTBufferQueue::setTransactionHangCallback( std::function callback) { std::lock_guard _lock{mMutex}; - mTransactionHangCallback = callback; + mTransactionHangCallback = std::move(callback); } +#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(BUFFER_RELEASE_CHANNEL) + +BLASTBufferQueue::BufferReleaseReader::BufferReleaseReader( + std::unique_ptr endpoint) + : mEndpoint{std::move(endpoint)} { + mEpollFd = android::base::unique_fd{epoll_create1(0)}; + LOG_ALWAYS_FATAL_IF(!mEpollFd.ok(), + "Failed to create buffer release epoll file descriptor. errno=%d " + "message='%s'", + errno, strerror(errno)); + + epoll_event registerEndpointFd{}; + registerEndpointFd.events = EPOLLIN; + registerEndpointFd.data.fd = mEndpoint->getFd(); + status_t status = + epoll_ctl(mEpollFd.get(), EPOLL_CTL_ADD, mEndpoint->getFd(), ®isterEndpointFd); + LOG_ALWAYS_FATAL_IF(status == -1, + "Failed to register buffer release consumer file descriptor with epoll. " + "errno=%d message='%s'", + errno, strerror(errno)); + + mEventFd = android::base::unique_fd(eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK)); + LOG_ALWAYS_FATAL_IF(!mEventFd.ok(), + "Failed to create buffer release event file descriptor. errno=%d " + "message='%s'", + errno, strerror(errno)); + + epoll_event registerEventFd{}; + registerEventFd.events = EPOLLIN; + registerEventFd.data.fd = mEventFd.get(); + status = epoll_ctl(mEpollFd.get(), EPOLL_CTL_ADD, mEventFd.get(), ®isterEventFd); + LOG_ALWAYS_FATAL_IF(status == -1, + "Failed to register buffer release event file descriptor with epoll. " + "errno=%d message='%s'", + errno, strerror(errno)); +} + +BLASTBufferQueue::BufferReleaseReader& BLASTBufferQueue::BufferReleaseReader::operator=( + BufferReleaseReader&& other) { + if (this != &other) { + ftl::FakeGuard guard{mMutex}; + ftl::FakeGuard otherGuard{other.mMutex}; + mEndpoint = std::move(other.mEndpoint); + mEpollFd = std::move(other.mEpollFd); + mEventFd = std::move(other.mEventFd); + } + return *this; +} + +status_t BLASTBufferQueue::BufferReleaseReader::readBlocking(ReleaseCallbackId& outId, + sp& outFence, + uint32_t& outMaxAcquiredBufferCount) { + epoll_event event{}; + while (true) { + int eventCount = epoll_wait(mEpollFd.get(), &event, 1 /* maxevents */, -1 /* timeout */); + if (eventCount == 1) { + break; + } + if (eventCount == -1 && errno != EINTR) { + ALOGE("epoll_wait error while waiting for buffer release. errno=%d message='%s'", errno, + strerror(errno)); + } + } + + if (event.data.fd == mEventFd.get()) { + uint64_t value; + if (read(mEventFd.get(), &value, sizeof(uint64_t)) == -1 && errno != EWOULDBLOCK) { + ALOGE("error while reading from eventfd. errno=%d message='%s'", errno, + strerror(errno)); + } + return WOULD_BLOCK; + } + + std::lock_guard lock{mMutex}; + return mEndpoint->readReleaseFence(outId, outFence, outMaxAcquiredBufferCount); +} + +void BLASTBufferQueue::BufferReleaseReader::interruptBlockingRead() { + uint64_t value = 1; + if (write(mEventFd.get(), &value, sizeof(uint64_t)) == -1) { + ALOGE("failed to notify dequeue event. errno=%d message='%s'", errno, strerror(errno)); + } +} + +void BLASTBufferQueue::BufferReleaseThread::start(const sp& bbq) { + mRunning = std::make_shared(true); + mReader = bbq->mBufferReleaseReader; + std::thread([running = mRunning, reader = mReader, weakBbq = wp(bbq)]() { + pthread_setname_np(pthread_self(), "BufferReleaseThread"); + while (*running) { + ReleaseCallbackId id; + sp fence; + uint32_t maxAcquiredBufferCount; + if (status_t status = reader->readBlocking(id, fence, maxAcquiredBufferCount); + status != OK) { + continue; + } + sp bbq = weakBbq.promote(); + if (!bbq) { + return; + } + bbq->releaseBufferCallback(id, fence, maxAcquiredBufferCount); + } + }).detach(); +} + +BLASTBufferQueue::BufferReleaseThread::~BufferReleaseThread() { + *mRunning = false; + mReader->interruptBlockingRead(); +} + +#endif + } // namespace android -- cgit v1.2.3-59-g8ed1b