libs/hwui/renderthread/RenderThread.cpp - platform/frameworks/base - Gitiles

 /*
  * 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 "RenderThread.h"

 #include "CanvasContext.h"
 #include "DeviceInfo.h"
 #include "EglManager.h"
 #include "Readback.h"
 #include "RenderProxy.h"
 #include "VulkanManager.h"
 #include "hwui/Bitmap.h"
 #include "pipeline/skia/SkiaOpenGLPipeline.h"
 #include "pipeline/skia/SkiaVulkanPipeline.h"
 #include "renderstate/RenderState.h"
 #include "utils/FatVector.h"
 #include "utils/TimeUtils.h"

 #ifdef HWUI_GLES_WRAP_ENABLED
 #include "debug/GlesDriver.h"
 #endif

 #include <GrContextOptions.h>
 #include <gl/GrGLInterface.h>

 #include <gui/DisplayEventReceiver.h>
 #include <sys/resource.h>
 #include <utils/Condition.h>
 #include <utils/Log.h>
 #include <utils/Mutex.h>
 #include <thread>

 namespace android {
 namespace uirenderer {
 namespace renderthread {

 // Number of events to read at a time from the DisplayEventReceiver pipe.
 // The value should be large enough that we can quickly drain the pipe
 // using just a few large reads.
 static const size_t EVENT_BUFFER_SIZE = 100;

 static bool gHasRenderThreadInstance = false;

 static JVMAttachHook gOnStartHook = nullptr;

 class DisplayEventReceiverWrapper : public VsyncSource {
 public:
     DisplayEventReceiverWrapper(std::unique_ptr<DisplayEventReceiver>&& receiver)
             : mDisplayEventReceiver(std::move(receiver)) {}

     virtual void requestNextVsync() override {
         status_t status = mDisplayEventReceiver->requestNextVsync();
         LOG_ALWAYS_FATAL_IF(status != NO_ERROR, "requestNextVsync failed with status: %d", status);
     }

     virtual nsecs_t latestVsyncEvent() override {
         DisplayEventReceiver::Event buf[EVENT_BUFFER_SIZE];
         nsecs_t latest = 0;
         ssize_t n;
         while ((n = mDisplayEventReceiver->getEvents(buf, EVENT_BUFFER_SIZE)) > 0) {
             for (ssize_t i = 0; i < n; i++) {
                 const DisplayEventReceiver::Event& ev = buf[i];
                 switch (ev.header.type) {
                     case DisplayEventReceiver::DISPLAY_EVENT_VSYNC:
                         latest = ev.header.timestamp;
                         break;
                 }
             }
         }
         if (n < 0) {
             ALOGW("Failed to get events from display event receiver, status=%d", status_t(n));
         }
         return latest;
     }

 private:
     std::unique_ptr<DisplayEventReceiver> mDisplayEventReceiver;
 };

 class DummyVsyncSource : public VsyncSource {
 public:
     DummyVsyncSource(RenderThread* renderThread) : mRenderThread(renderThread) {}

     virtual void requestNextVsync() override {
         mRenderThread->queue().postDelayed(16_ms,
                                            [this]() { mRenderThread->drainDisplayEventQueue(); });
     }

     virtual nsecs_t latestVsyncEvent() override { return systemTime(CLOCK_MONOTONIC); }

 private:
     RenderThread* mRenderThread;
 };

 bool RenderThread::hasInstance() {
     return gHasRenderThreadInstance;
 }

 void RenderThread::setOnStartHook(JVMAttachHook onStartHook) {
     LOG_ALWAYS_FATAL_IF(hasInstance(), "can't set an onStartHook after we've started...");
     gOnStartHook = onStartHook;
 }

 JVMAttachHook RenderThread::getOnStartHook() {
     return gOnStartHook;
 }

 RenderThread& RenderThread::getInstance() {
     // This is a pointer because otherwise __cxa_finalize
     // will try to delete it like a Good Citizen but that causes us to crash
     // because we don't want to delete the RenderThread normally.
     static RenderThread* sInstance = new RenderThread();
     gHasRenderThreadInstance = true;
     return *sInstance;
 }

 RenderThread::RenderThread()
         : ThreadBase()
         , mVsyncSource(nullptr)
         , mVsyncRequested(false)
         , mFrameCallbackTaskPending(false)
         , mRenderState(nullptr)
         , mEglManager(nullptr)
         , mFunctorManager(WebViewFunctorManager::instance())
         , mVkManager(nullptr) {
     Properties::load();
     start("RenderThread");
 }

 RenderThread::~RenderThread() {
     LOG_ALWAYS_FATAL("Can't destroy the render thread");
 }

 void RenderThread::initializeDisplayEventReceiver() {
     LOG_ALWAYS_FATAL_IF(mVsyncSource, "Initializing a second DisplayEventReceiver?");

     if (!Properties::isolatedProcess) {
         auto receiver = std::make_unique<DisplayEventReceiver>();
         status_t status = receiver->initCheck();
         LOG_ALWAYS_FATAL_IF(status != NO_ERROR,
                             "Initialization of DisplayEventReceiver "
                             "failed with status: %d",
                             status);

         // Register the FD
         mLooper->addFd(receiver->getFd(), 0, Looper::EVENT_INPUT,
                        RenderThread::displayEventReceiverCallback, this);
         mVsyncSource = new DisplayEventReceiverWrapper(std::move(receiver));
     } else {
         mVsyncSource = new DummyVsyncSource(this);
     }
 }

 void RenderThread::initThreadLocals() {
     mDisplayInfo = DeviceInfo::get()->displayInfo();
     nsecs_t frameIntervalNanos = static_cast<nsecs_t>(1000000000 / mDisplayInfo.fps);
     mTimeLord.setFrameInterval(frameIntervalNanos);
     mDispatchFrameDelay = static_cast<nsecs_t>(frameIntervalNanos * .25f);
     initializeDisplayEventReceiver();
     mEglManager = new EglManager();
     mRenderState = new RenderState(*this);
     mVkManager = new VulkanManager();
     mCacheManager = new CacheManager(mDisplayInfo);
 }

 void RenderThread::requireGlContext() {
     if (mEglManager->hasEglContext()) {
         return;
     }
     mEglManager->initialize();

 #ifdef HWUI_GLES_WRAP_ENABLED
     debug::GlesDriver* driver = debug::GlesDriver::get();
     sk_sp<const GrGLInterface> glInterface(driver->getSkiaInterface());
 #else
     sk_sp<const GrGLInterface> glInterface(GrGLCreateNativeInterface());
 #endif
     LOG_ALWAYS_FATAL_IF(!glInterface.get());

     GrContextOptions options;
     initGrContextOptions(options);
     auto glesVersion = reinterpret_cast<const char*>(glGetString(GL_VERSION));
     auto size = glesVersion ? strlen(glesVersion) : -1;
     cacheManager().configureContext(&options, glesVersion, size);
     sk_sp<GrContext> grContext(GrContext::MakeGL(std::move(glInterface), options));
     LOG_ALWAYS_FATAL_IF(!grContext.get());
     setGrContext(grContext);
 }

 void RenderThread::requireVkContext() {
     if (mVkManager->hasVkContext()) {
         return;
     }
     mVkManager->initialize();
     GrContextOptions options;
     initGrContextOptions(options);
     // TODO: get a string describing the SPIR-V compiler version and use it here
     cacheManager().configureContext(&options, nullptr, 0);
     sk_sp<GrContext> grContext = mVkManager->createContext(options);
     LOG_ALWAYS_FATAL_IF(!grContext.get());
     setGrContext(grContext);
 }

 void RenderThread::initGrContextOptions(GrContextOptions& options) {
     options.fPreferExternalImagesOverES3 = true;
     options.fDisableDistanceFieldPaths = true;
 }

 void RenderThread::destroyRenderingContext() {
     mFunctorManager.onContextDestroyed();
     if (Properties::getRenderPipelineType() == RenderPipelineType::SkiaGL) {
         if (mEglManager->hasEglContext()) {
             setGrContext(nullptr);
             mEglManager->destroy();
         }
     } else {
         if (vulkanManager().hasVkContext()) {
             setGrContext(nullptr);
             vulkanManager().destroy();
         }
     }
 }

 void RenderThread::dumpGraphicsMemory(int fd) {
     globalProfileData()->dump(fd);

     String8 cachesOutput;
     String8 pipeline;
     auto renderType = Properties::getRenderPipelineType();
     switch (renderType) {
         case RenderPipelineType::SkiaGL: {
             mCacheManager->dumpMemoryUsage(cachesOutput, mRenderState);
             pipeline.appendFormat("Skia (OpenGL)");
             break;
         }
         case RenderPipelineType::SkiaVulkan: {
             mCacheManager->dumpMemoryUsage(cachesOutput, mRenderState);
             pipeline.appendFormat("Skia (Vulkan)");
             break;
         }
         default:
             LOG_ALWAYS_FATAL("canvas context type %d not supported", (int32_t)renderType);
             break;
     }

     dprintf(fd, "\n%s\n", cachesOutput.string());
     dprintf(fd, "\nPipeline=%s\n", pipeline.string());
 }

 Readback& RenderThread::readback() {
     if (!mReadback) {
         mReadback = new Readback(*this);
     }

     return *mReadback;
 }

 void RenderThread::setGrContext(sk_sp<GrContext> context) {
     mCacheManager->reset(context);
     if (mGrContext) {
         mRenderState->onContextDestroyed();
         mGrContext->releaseResourcesAndAbandonContext();
     }
     mGrContext = std::move(context);
     if (mGrContext) {
         mRenderState->onContextCreated();
         DeviceInfo::setMaxTextureSize(mGrContext->maxRenderTargetSize());
     }
 }

 int RenderThread::displayEventReceiverCallback(int fd, int events, void* data) {
     if (events & (Looper::EVENT_ERROR | Looper::EVENT_HANGUP)) {
         ALOGE("Display event receiver pipe was closed or an error occurred.  "
               "events=0x%x",
               events);
         return 0;  // remove the callback
     }

     if (!(events & Looper::EVENT_INPUT)) {
         ALOGW("Received spurious callback for unhandled poll event.  "
               "events=0x%x",
               events);
         return 1;  // keep the callback
     }

     reinterpret_cast<RenderThread*>(data)->drainDisplayEventQueue();

     return 1;  // keep the callback
 }

 void RenderThread::drainDisplayEventQueue() {
     ATRACE_CALL();
     nsecs_t vsyncEvent = mVsyncSource->latestVsyncEvent();
     if (vsyncEvent > 0) {
         mVsyncRequested = false;
         if (mTimeLord.vsyncReceived(vsyncEvent) && !mFrameCallbackTaskPending) {
             ATRACE_NAME("queue mFrameCallbackTask");
             mFrameCallbackTaskPending = true;
             nsecs_t runAt = (vsyncEvent + mDispatchFrameDelay);
             queue().postAt(runAt, [this]() { dispatchFrameCallbacks(); });
         }
     }
 }

 void RenderThread::dispatchFrameCallbacks() {
     ATRACE_CALL();
     mFrameCallbackTaskPending = false;

     std::set<IFrameCallback*> callbacks;
     mFrameCallbacks.swap(callbacks);

     if (callbacks.size()) {
         // Assume one of them will probably animate again so preemptively
         // request the next vsync in case it occurs mid-frame
         requestVsync();
         for (std::set<IFrameCallback*>::iterator it = callbacks.begin(); it != callbacks.end();
              it++) {
             (*it)->doFrame();
         }
     }
 }

 void RenderThread::requestVsync() {
     if (!mVsyncRequested) {
         mVsyncRequested = true;
         mVsyncSource->requestNextVsync();
     }
 }

 bool RenderThread::threadLoop() {
     setpriority(PRIO_PROCESS, 0, PRIORITY_DISPLAY);
     Looper::setForThread(mLooper);
     if (gOnStartHook) {
         gOnStartHook("RenderThread");
     }
     initThreadLocals();

     while (true) {
         waitForWork();
         processQueue();

         if (mPendingRegistrationFrameCallbacks.size() && !mFrameCallbackTaskPending) {
             drainDisplayEventQueue();
             mFrameCallbacks.insert(mPendingRegistrationFrameCallbacks.begin(),
                                    mPendingRegistrationFrameCallbacks.end());
             mPendingRegistrationFrameCallbacks.clear();
             requestVsync();
         }

         if (!mFrameCallbackTaskPending && !mVsyncRequested && mFrameCallbacks.size()) {
             // TODO: Clean this up. This is working around an issue where a combination
             // of bad timing and slow drawing can result in dropping a stale vsync
             // on the floor (correct!) but fails to schedule to listen for the
             // next vsync (oops), so none of the callbacks are run.
             requestVsync();
         }
     }

     return false;
 }

 void RenderThread::postFrameCallback(IFrameCallback* callback) {
     mPendingRegistrationFrameCallbacks.insert(callback);
 }

 bool RenderThread::removeFrameCallback(IFrameCallback* callback) {
     size_t erased;
     erased = mFrameCallbacks.erase(callback);
     erased |= mPendingRegistrationFrameCallbacks.erase(callback);
     return erased;
 }

 void RenderThread::pushBackFrameCallback(IFrameCallback* callback) {
     if (mFrameCallbacks.erase(callback)) {
         mPendingRegistrationFrameCallbacks.insert(callback);
     }
 }

 sk_sp<Bitmap> RenderThread::allocateHardwareBitmap(SkBitmap& skBitmap) {
     auto renderType = Properties::getRenderPipelineType();
     switch (renderType) {
         case RenderPipelineType::SkiaVulkan:
             return skiapipeline::SkiaVulkanPipeline::allocateHardwareBitmap(*this, skBitmap);
         default:
             LOG_ALWAYS_FATAL("canvas context type %d not supported", (int32_t)renderType);
             break;
     }
     return nullptr;
 }

 bool RenderThread::isCurrent() {
     return gettid() == getInstance().getTid();
 }

 void RenderThread::preload() {
     std::thread eglInitThread([]() {
         //TODO: don't load EGL drivers for Vulkan, when HW bitmap uploader is refactored.
         eglGetDisplay(EGL_DEFAULT_DISPLAY);
     });
     eglInitThread.detach();
     if (Properties::getRenderPipelineType() == RenderPipelineType::SkiaVulkan) {
         requireVkContext();
     }
 }

 } /* namespace renderthread */
 } /* namespace uirenderer */
 } /* namespace android */
	/*
	* 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 "RenderThread.h"

	#include "CanvasContext.h"
	#include "DeviceInfo.h"
	#include "EglManager.h"
	#include "Readback.h"
	#include "RenderProxy.h"
	#include "VulkanManager.h"
	#include "hwui/Bitmap.h"
	#include "pipeline/skia/SkiaOpenGLPipeline.h"
	#include "pipeline/skia/SkiaVulkanPipeline.h"
	#include "renderstate/RenderState.h"
	#include "utils/FatVector.h"
	#include "utils/TimeUtils.h"

	#ifdef HWUI_GLES_WRAP_ENABLED
	#include "debug/GlesDriver.h"
	#endif

	#include <GrContextOptions.h>
	#include <gl/GrGLInterface.h>

	#include <gui/DisplayEventReceiver.h>
	#include <sys/resource.h>
	#include <utils/Condition.h>
	#include <utils/Log.h>
	#include <utils/Mutex.h>
	#include <thread>

	namespace android {
	namespace uirenderer {
	namespace renderthread {

	// Number of events to read at a time from the DisplayEventReceiver pipe.
	// The value should be large enough that we can quickly drain the pipe
	// using just a few large reads.
	static const size_t EVENT_BUFFER_SIZE = 100;

	static bool gHasRenderThreadInstance = false;

	static JVMAttachHook gOnStartHook = nullptr;

	class DisplayEventReceiverWrapper : public VsyncSource {
	public:
	DisplayEventReceiverWrapper(std::unique_ptr<DisplayEventReceiver>&& receiver)
	: mDisplayEventReceiver(std::move(receiver)) {}

	virtual void requestNextVsync() override {
	status_t status = mDisplayEventReceiver->requestNextVsync();
	LOG_ALWAYS_FATAL_IF(status != NO_ERROR, "requestNextVsync failed with status: %d", status);
	}

	virtual nsecs_t latestVsyncEvent() override {
	DisplayEventReceiver::Event buf[EVENT_BUFFER_SIZE];
	nsecs_t latest = 0;
	ssize_t n;
	while ((n = mDisplayEventReceiver->getEvents(buf, EVENT_BUFFER_SIZE)) > 0) {
	for (ssize_t i = 0; i < n; i++) {
	const DisplayEventReceiver::Event& ev = buf[i];
	switch (ev.header.type) {
	case DisplayEventReceiver::DISPLAY_EVENT_VSYNC:
	latest = ev.header.timestamp;
	break;
	}
	}
	}
	if (n < 0) {
	ALOGW("Failed to get events from display event receiver, status=%d", status_t(n));
	}
	return latest;
	}

	private:
	std::unique_ptr<DisplayEventReceiver> mDisplayEventReceiver;
	};

	class DummyVsyncSource : public VsyncSource {
	public:
	DummyVsyncSource(RenderThread* renderThread) : mRenderThread(renderThread) {}

	virtual void requestNextVsync() override {
	mRenderThread->queue().postDelayed(16_ms,
	[this]() { mRenderThread->drainDisplayEventQueue(); });
	}

	virtual nsecs_t latestVsyncEvent() override { return systemTime(CLOCK_MONOTONIC); }

	private:
	RenderThread* mRenderThread;
	};

	bool RenderThread::hasInstance() {
	return gHasRenderThreadInstance;
	}

	void RenderThread::setOnStartHook(JVMAttachHook onStartHook) {
	LOG_ALWAYS_FATAL_IF(hasInstance(), "can't set an onStartHook after we've started...");
	gOnStartHook = onStartHook;
	}

	JVMAttachHook RenderThread::getOnStartHook() {
	return gOnStartHook;
	}

	RenderThread& RenderThread::getInstance() {
	// This is a pointer because otherwise __cxa_finalize
	// will try to delete it like a Good Citizen but that causes us to crash
	// because we don't want to delete the RenderThread normally.
	static RenderThread* sInstance = new RenderThread();
	gHasRenderThreadInstance = true;
	return *sInstance;
	}

	RenderThread::RenderThread()
	: ThreadBase()
	, mVsyncSource(nullptr)
	, mVsyncRequested(false)
	, mFrameCallbackTaskPending(false)
	, mRenderState(nullptr)
	, mEglManager(nullptr)
	, mFunctorManager(WebViewFunctorManager::instance())
	, mVkManager(nullptr) {
	Properties::load();
	start("RenderThread");
	}

	RenderThread::~RenderThread() {
	LOG_ALWAYS_FATAL("Can't destroy the render thread");
	}

	void RenderThread::initializeDisplayEventReceiver() {
	LOG_ALWAYS_FATAL_IF(mVsyncSource, "Initializing a second DisplayEventReceiver?");

	if (!Properties::isolatedProcess) {
	auto receiver = std::make_unique<DisplayEventReceiver>();
	status_t status = receiver->initCheck();
	LOG_ALWAYS_FATAL_IF(status != NO_ERROR,
	"Initialization of DisplayEventReceiver "
	"failed with status: %d",
	status);

	// Register the FD
	mLooper->addFd(receiver->getFd(), 0, Looper::EVENT_INPUT,
	RenderThread::displayEventReceiverCallback, this);
	mVsyncSource = new DisplayEventReceiverWrapper(std::move(receiver));
	} else {
	mVsyncSource = new DummyVsyncSource(this);
	}
	}

	void RenderThread::initThreadLocals() {
	mDisplayInfo = DeviceInfo::get()->displayInfo();
	nsecs_t frameIntervalNanos = static_cast<nsecs_t>(1000000000 / mDisplayInfo.fps);
	mTimeLord.setFrameInterval(frameIntervalNanos);
	mDispatchFrameDelay = static_cast<nsecs_t>(frameIntervalNanos * .25f);
	initializeDisplayEventReceiver();
	mEglManager = new EglManager();
	mRenderState = new RenderState(*this);
	mVkManager = new VulkanManager();
	mCacheManager = new CacheManager(mDisplayInfo);
	}

	void RenderThread::requireGlContext() {
	if (mEglManager->hasEglContext()) {
	return;
	}
	mEglManager->initialize();

	#ifdef HWUI_GLES_WRAP_ENABLED
	debug::GlesDriver* driver = debug::GlesDriver::get();
	sk_sp<const GrGLInterface> glInterface(driver->getSkiaInterface());
	#else
	sk_sp<const GrGLInterface> glInterface(GrGLCreateNativeInterface());
	#endif
	LOG_ALWAYS_FATAL_IF(!glInterface.get());

	GrContextOptions options;
	initGrContextOptions(options);
	auto glesVersion = reinterpret_cast<const char*>(glGetString(GL_VERSION));
	auto size = glesVersion ? strlen(glesVersion) : -1;
	cacheManager().configureContext(&options, glesVersion, size);
	sk_sp<GrContext> grContext(GrContext::MakeGL(std::move(glInterface), options));
	LOG_ALWAYS_FATAL_IF(!grContext.get());
	setGrContext(grContext);
	}

	void RenderThread::requireVkContext() {
	if (mVkManager->hasVkContext()) {
	return;
	}
	mVkManager->initialize();
	GrContextOptions options;
	initGrContextOptions(options);
	// TODO: get a string describing the SPIR-V compiler version and use it here
	cacheManager().configureContext(&options, nullptr, 0);
	sk_sp<GrContext> grContext = mVkManager->createContext(options);
	LOG_ALWAYS_FATAL_IF(!grContext.get());
	setGrContext(grContext);
	}

	void RenderThread::initGrContextOptions(GrContextOptions& options) {
	options.fPreferExternalImagesOverES3 = true;
	options.fDisableDistanceFieldPaths = true;
	}

	void RenderThread::destroyRenderingContext() {
	mFunctorManager.onContextDestroyed();
	if (Properties::getRenderPipelineType() == RenderPipelineType::SkiaGL) {
	if (mEglManager->hasEglContext()) {
	setGrContext(nullptr);
	mEglManager->destroy();
	}
	} else {
	if (vulkanManager().hasVkContext()) {
	setGrContext(nullptr);
	vulkanManager().destroy();
	}
	}
	}

	void RenderThread::dumpGraphicsMemory(int fd) {
	globalProfileData()->dump(fd);

	String8 cachesOutput;
	String8 pipeline;
	auto renderType = Properties::getRenderPipelineType();
	switch (renderType) {
	case RenderPipelineType::SkiaGL: {
	mCacheManager->dumpMemoryUsage(cachesOutput, mRenderState);
	pipeline.appendFormat("Skia (OpenGL)");
	break;
	}
	case RenderPipelineType::SkiaVulkan: {
	mCacheManager->dumpMemoryUsage(cachesOutput, mRenderState);
	pipeline.appendFormat("Skia (Vulkan)");
	break;
	}
	default:
	LOG_ALWAYS_FATAL("canvas context type %d not supported", (int32_t)renderType);
	break;
	}

	dprintf(fd, "\n%s\n", cachesOutput.string());
	dprintf(fd, "\nPipeline=%s\n", pipeline.string());
	}

	Readback& RenderThread::readback() {
	if (!mReadback) {
	mReadback = new Readback(*this);
	}

	return *mReadback;
	}

	void RenderThread::setGrContext(sk_sp<GrContext> context) {
	mCacheManager->reset(context);
	if (mGrContext) {
	mRenderState->onContextDestroyed();
	mGrContext->releaseResourcesAndAbandonContext();
	}
	mGrContext = std::move(context);
	if (mGrContext) {
	mRenderState->onContextCreated();
	DeviceInfo::setMaxTextureSize(mGrContext->maxRenderTargetSize());
	}
	}

	int RenderThread::displayEventReceiverCallback(int fd, int events, void* data) {
	if (events & (Looper::EVENT_ERROR \| Looper::EVENT_HANGUP)) {
	ALOGE("Display event receiver pipe was closed or an error occurred. "
	"events=0x%x",
	events);
	return 0; // remove the callback
	}

	if (!(events & Looper::EVENT_INPUT)) {
	ALOGW("Received spurious callback for unhandled poll event. "
	"events=0x%x",
	events);
	return 1; // keep the callback
	}

	reinterpret_cast<RenderThread*>(data)->drainDisplayEventQueue();

	return 1; // keep the callback
	}

	void RenderThread::drainDisplayEventQueue() {
	ATRACE_CALL();
	nsecs_t vsyncEvent = mVsyncSource->latestVsyncEvent();
	if (vsyncEvent > 0) {
	mVsyncRequested = false;
	if (mTimeLord.vsyncReceived(vsyncEvent) && !mFrameCallbackTaskPending) {
	ATRACE_NAME("queue mFrameCallbackTask");
	mFrameCallbackTaskPending = true;
	nsecs_t runAt = (vsyncEvent + mDispatchFrameDelay);
	queue().postAt(runAt, [this]() { dispatchFrameCallbacks(); });
	}
	}
	}

	void RenderThread::dispatchFrameCallbacks() {
	ATRACE_CALL();
	mFrameCallbackTaskPending = false;

	std::set<IFrameCallback*> callbacks;
	mFrameCallbacks.swap(callbacks);

	if (callbacks.size()) {
	// Assume one of them will probably animate again so preemptively
	// request the next vsync in case it occurs mid-frame
	requestVsync();
	for (std::set<IFrameCallback*>::iterator it = callbacks.begin(); it != callbacks.end();
	it++) {
	(*it)->doFrame();
	}
	}
	}

	void RenderThread::requestVsync() {
	if (!mVsyncRequested) {
	mVsyncRequested = true;
	mVsyncSource->requestNextVsync();
	}
	}

	bool RenderThread::threadLoop() {
	setpriority(PRIO_PROCESS, 0, PRIORITY_DISPLAY);
	Looper::setForThread(mLooper);
	if (gOnStartHook) {
	gOnStartHook("RenderThread");
	}
	initThreadLocals();

	while (true) {
	waitForWork();
	processQueue();

	if (mPendingRegistrationFrameCallbacks.size() && !mFrameCallbackTaskPending) {
	drainDisplayEventQueue();
	mFrameCallbacks.insert(mPendingRegistrationFrameCallbacks.begin(),
	mPendingRegistrationFrameCallbacks.end());
	mPendingRegistrationFrameCallbacks.clear();
	requestVsync();
	}

	if (!mFrameCallbackTaskPending && !mVsyncRequested && mFrameCallbacks.size()) {
	// TODO: Clean this up. This is working around an issue where a combination
	// of bad timing and slow drawing can result in dropping a stale vsync
	// on the floor (correct!) but fails to schedule to listen for the
	// next vsync (oops), so none of the callbacks are run.
	requestVsync();
	}
	}

	return false;
	}

	void RenderThread::postFrameCallback(IFrameCallback* callback) {
	mPendingRegistrationFrameCallbacks.insert(callback);
	}

	bool RenderThread::removeFrameCallback(IFrameCallback* callback) {
	size_t erased;
	erased = mFrameCallbacks.erase(callback);
	erased \|= mPendingRegistrationFrameCallbacks.erase(callback);
	return erased;
	}

	void RenderThread::pushBackFrameCallback(IFrameCallback* callback) {
	if (mFrameCallbacks.erase(callback)) {
	mPendingRegistrationFrameCallbacks.insert(callback);
	}
	}

	sk_sp<Bitmap> RenderThread::allocateHardwareBitmap(SkBitmap& skBitmap) {
	auto renderType = Properties::getRenderPipelineType();
	switch (renderType) {
	case RenderPipelineType::SkiaVulkan:
	return skiapipeline::SkiaVulkanPipeline::allocateHardwareBitmap(*this, skBitmap);
	default:
	LOG_ALWAYS_FATAL("canvas context type %d not supported", (int32_t)renderType);
	break;
	}
	return nullptr;
	}

	bool RenderThread::isCurrent() {
	return gettid() == getInstance().getTid();
	}

	void RenderThread::preload() {
	std::thread eglInitThread([]() {
	//TODO: don't load EGL drivers for Vulkan, when HW bitmap uploader is refactored.
	eglGetDisplay(EGL_DEFAULT_DISPLAY);
	});
	eglInitThread.detach();
	if (Properties::getRenderPipelineType() == RenderPipelineType::SkiaVulkan) {
	requireVkContext();
	}
	}

	} /* namespace renderthread */
	} /* namespace uirenderer */
	} /* namespace android */