stream-servers/SyncThread.cpp - device/generic/vulkan-cereal - Git at Google

 /*
 * Copyright (C) 2016 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 "SyncThread.h"

 #include "base/System.h"
 #include "base/Thread.h"
 #include "OpenGLESDispatch/OpenGLDispatchLoader.h"
 #include "host-common/crash_reporter.h"
 #include "host-common/sync_device.h"

 #ifndef _MSC_VER
 #include <sys/time.h>
 #endif
 #include <memory>

 #define DEBUG 0

 #if DEBUG

 static uint64_t curr_ms() {
     struct timeval tv;
     gettimeofday(&tv, NULL);
     return tv.tv_usec / 1000 + tv.tv_sec * 1000;
 }

 #define DPRINT(fmt, ...) do { \
     if (!VERBOSE_CHECK(syncthreads)) VERBOSE_ENABLE(syncthreads); \
     VERBOSE_TID_FUNCTION_DPRINT(syncthreads, "@ time=%llu: " fmt, curr_ms(), ##__VA_ARGS__); \
 } while(0)

 #else

 #define DPRINT(...)

 #endif

 // The single global sync thread instance.
 class GlobalSyncThread {
 public:
     GlobalSyncThread() = default;

     SyncThread* syncThreadPtr() { return &mSyncThread; }

 private:
     SyncThread mSyncThread;
 };

 static GlobalSyncThread* sGlobalSyncThread() {
     static GlobalSyncThread* t = new GlobalSyncThread;
     return t;
 }

 static const uint32_t kTimelineInterval = 1;
 static const uint64_t kDefaultTimeoutNsecs = 5ULL * 1000ULL * 1000ULL * 1000ULL;
 static const uint64_t kNumWorkerThreads = 1u;

 SyncThread::SyncThread()
     : android::base::Thread(android::base::ThreadFlags::MaskSignals, 512 * 1024),
       mWorkerThreadPool(kNumWorkerThreads, [this](SyncThreadCmd&& cmd) {
           doSyncThreadCmd(&cmd);
       }) {
     this->start();
     mWorkerThreadPool.start();
     initSyncContext();
 }

 SyncThread::~SyncThread() {
     cleanup();
 }

 void SyncThread::triggerWait(FenceSync* fenceSync,
                              uint64_t timeline) {
     DPRINT("fenceSyncInfo=0x%llx timeline=0x%lx ...",
             fenceSync, timeline);
     SyncThreadCmd to_send;
     to_send.opCode = SYNC_THREAD_WAIT;
     to_send.fenceSync = fenceSync;
     to_send.timeline = timeline;
     DPRINT("opcode=%u", to_send.opCode);
     sendAsync(to_send);
     DPRINT("exit");
 }

 void SyncThread::triggerWaitVk(VkFence vkFence, uint64_t timeline) {
     DPRINT("fenceSyncInfo=0x%llx timeline=0x%lx ...", fenceSync, timeline);
     SyncThreadCmd to_send;
     to_send.opCode = SYNC_THREAD_WAIT_VK;
     to_send.vkFence = vkFence;
     to_send.timeline = timeline;
     DPRINT("opcode=%u", to_send.opCode);
     sendAsync(to_send);
     DPRINT("exit");
 }

 void SyncThread::triggerBlockedWaitNoTimeline(FenceSync* fenceSync) {
     DPRINT("fenceSyncInfo=0x%llx ...", fenceSync);
     SyncThreadCmd to_send;
     to_send.opCode = SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE;
     to_send.fenceSync = fenceSync;
     DPRINT("opcode=%u", to_send.opCode);
     sendAndWaitForResult(to_send);
     DPRINT("exit");
 }

 void SyncThread::cleanup() {
     DPRINT("enter");
     SyncThreadCmd to_send;
     to_send.opCode = SYNC_THREAD_EXIT;
     sendAndWaitForResult(to_send);
     DPRINT("signal");
     mLock.lock();
     mExiting = true;
     mCv.signalAndUnlock(&mLock);
     DPRINT("exit");
 }

 // Private methods below////////////////////////////////////////////////////////

 void SyncThread::initSyncContext() {
     DPRINT("enter");
     SyncThreadCmd to_send;
     to_send.opCode = SYNC_THREAD_INIT;
     sendAndWaitForResult(to_send);
     DPRINT("exit");
 }

 intptr_t SyncThread::main() {
     DPRINT("in sync thread");
     mLock.lock();
     mCv.wait(&mLock, [this] { return mExiting; });

     mWorkerThreadPool.done();
     mWorkerThreadPool.join();
     DPRINT("exited sync thread");
     return 0;
 }

 int SyncThread::sendAndWaitForResult(SyncThreadCmd& cmd) {
     DPRINT("send with opcode=%d", cmd.opCode);
     android::base::Lock lock;
     android::base::ConditionVariable cond;
     android::base::Optional<int> result = android::base::kNullopt;
     cmd.lock = &lock;
     cmd.cond = &cond;
     cmd.result = &result;

     lock.lock();
     mWorkerThreadPool.enqueue(std::move(cmd));
     cond.wait(&lock, [&result] { return result.hasValue(); });

     DPRINT("result=%d", *result);
     return *result;
 }

 void SyncThread::sendAsync(SyncThreadCmd& cmd) {
     DPRINT("send with opcode=%u fenceSyncInfo=0x%llx",
            cmd.opCode, cmd.fenceSync);
     mWorkerThreadPool.enqueue(std::move(cmd));
 }

 void SyncThread::doSyncContextInit() {
     const EGLDispatch* egl = emugl::LazyLoadedEGLDispatch::get();

     mDisplay = egl->eglGetDisplay(EGL_DEFAULT_DISPLAY);
     int eglMaj, eglMin;
     egl->eglInitialize(mDisplay, &eglMaj , &eglMin);

     const EGLint configAttribs[] = {
         EGL_SURFACE_TYPE, EGL_PBUFFER_BIT,
         EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
         EGL_RED_SIZE, 8,
         EGL_GREEN_SIZE, 8,
         EGL_BLUE_SIZE, 8,
         EGL_NONE,
     };

     EGLint nConfigs;
     EGLConfig config;

     egl->eglChooseConfig(mDisplay, configAttribs, &config, 1, &nConfigs);

     const EGLint pbufferAttribs[] = {
         EGL_WIDTH, 1,
         EGL_HEIGHT, 1,
         EGL_NONE,
     };

     mSurface =
         egl->eglCreatePbufferSurface(mDisplay, config, pbufferAttribs);

     const EGLint contextAttribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
     mContext = egl->eglCreateContext(mDisplay, config, EGL_NO_CONTEXT, contextAttribs);

     egl->eglMakeCurrent(mDisplay, mSurface, mSurface, mContext);
 }

 void SyncThread::doSyncWait(SyncThreadCmd* cmd) {
     DPRINT("enter");

     FenceSync* fenceSync =
         FenceSync::getFromHandle((uint64_t)(uintptr_t)cmd->fenceSync);

     if (!fenceSync) {
         emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);
         return;
     }

     EGLint wait_result = 0x0;

     DPRINT("wait on sync obj: %p", cmd->fenceSync);
     wait_result = cmd->fenceSync->wait(kDefaultTimeoutNsecs);

     DPRINT("done waiting, with wait result=0x%x. "
            "increment timeline (and signal fence)",
            wait_result);

     if (wait_result != EGL_CONDITION_SATISFIED_KHR) {
         DPRINT("error: eglClientWaitSync abnormal exit 0x%x. sync handle 0x%llx\n",
                wait_result, (unsigned long long)cmd->fenceSync);
     }

     DPRINT("issue timeline increment");

     // We always unconditionally increment timeline at this point, even
     // if the call to eglClientWaitSync returned abnormally.
     // There are three cases to consider:
     // - EGL_CONDITION_SATISFIED_KHR: either the sync object is already
     //   signaled and we need to increment this timeline immediately, or
     //   we have waited until the object is signaled, and then
     //   we increment the timeline.
     // - EGL_TIMEOUT_EXPIRED_KHR: the fence command we put in earlier
     //   in the OpenGL stream is not actually ever signaled, and we
     //   end up blocking in the above eglClientWaitSyncKHR call until
     //   our timeout runs out. In this case, provided we have waited
     //   for |kDefaultTimeoutNsecs|, the guest will have received all
     //   relevant error messages about fence fd's not being signaled
     //   in time, so we are properly emulating bad behavior even if
     //   we now increment the timeline.
     // - EGL_FALSE (error): chances are, the underlying EGL implementation
     //   on the host doesn't actually support fence objects. In this case,
     //   we should fail safe: 1) It must be only very old or faulty
     //   graphics drivers / GPU's that don't support fence objects.
     //   2) The consequences of signaling too early are generally, out of
     //   order frames and scrambled textures in some apps. But, not
     //   incrementing the timeline means that the app's rendering freezes.
     //   So, despite the faulty GPU driver, not incrementing is too heavyweight a response.

     emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);
     FenceSync::incrementTimelineAndDeleteOldFences();

     DPRINT("done timeline increment");

     DPRINT("exit");
 }

 int SyncThread::doSyncWaitVk(SyncThreadCmd* cmd) {
     DPRINT("enter");

     auto decoder = goldfish_vk::VkDecoderGlobalState::get();
     auto result = decoder->waitForFence(cmd->vkFence, kDefaultTimeoutNsecs);
     if (result == VK_TIMEOUT) {
         fprintf(stderr, "SyncThread::%s: SYNC_WAIT_VK timeout: vkFence=%p\n",
                 __func__, cmd->vkFence);
     } else if (result != VK_SUCCESS) {
         fprintf(stderr, "SyncThread::%s: SYNC_WAIT_VK error: %d vkFence=%p\n",
                 __func__, result, cmd->vkFence);
     }

     DPRINT("issue timeline increment");

     // We always unconditionally increment timeline at this point, even
     // if the call to vkWaitForFences returned abnormally.
     // See comments in |doSyncWait| about the rationale.
     emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);

     DPRINT("done timeline increment");

     DPRINT("exit");
     return result;
 }

 void SyncThread::doSyncBlockedWaitNoTimeline(SyncThreadCmd* cmd) {
     DPRINT("enter");

     FenceSync* fenceSync =
         FenceSync::getFromHandle((uint64_t)(uintptr_t)cmd->fenceSync);

     if (!fenceSync) {
         return;
     }

     EGLint wait_result = 0x0;

     DPRINT("wait on sync obj: %p", cmd->fenceSync);
     wait_result = cmd->fenceSync->wait(kDefaultTimeoutNsecs);

     DPRINT("done waiting, with wait result=0x%x. "
            "increment timeline (and signal fence)",
            wait_result);

     if (wait_result != EGL_CONDITION_SATISFIED_KHR) {
         fprintf(stderr, "error: eglClientWaitSync abnormal exit 0x%x %p\n",
                 wait_result, cmd->fenceSync);
     }
 }

 void SyncThread::doExit() {

     if (mContext == EGL_NO_CONTEXT) return;

     const EGLDispatch* egl = emugl::LazyLoadedEGLDispatch::get();

     egl->eglMakeCurrent(mDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
     egl->eglDestroyContext(mDisplay, mContext);
     egl->eglDestroySurface(mDisplay, mContext);
     mContext = EGL_NO_CONTEXT;
     mSurface = EGL_NO_SURFACE;
 }

 int SyncThread::doSyncThreadCmd(SyncThreadCmd* cmd) {
 #if DEBUG
     thread_local static auto threadId = android::base::getCurrentThreadId();
     thread_local static size_t numCommands = 0U;
     DPRINT("threadId = %lu numCommands = %lu cmd = %p", threadId, ++numCommands,
            cmd);
 #endif  // DEBUG

     int result = 0;
     switch (cmd->opCode) {
     case SYNC_THREAD_INIT:
         DPRINT("exec SYNC_THREAD_INIT");
         doSyncContextInit();
         break;
     case SYNC_THREAD_WAIT:
         DPRINT("exec SYNC_THREAD_WAIT");
         doSyncWait(cmd);
         break;
     case SYNC_THREAD_WAIT_VK:
         DPRINT("exec SYNC_THREAD_WAIT_VK");
         result = doSyncWaitVk(cmd);
         break;
     case SYNC_THREAD_EXIT:
         DPRINT("exec SYNC_THREAD_EXIT");
         doExit();
         break;
     case SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE:
         DPRINT("exec SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE");
         doSyncBlockedWaitNoTimeline(cmd);
         break;
     }

     bool need_reply = cmd->lock != nullptr && cmd->cond != nullptr;
     if (need_reply) {
         cmd->lock->lock();
         *cmd->result = android::base::makeOptional(result);
         cmd->cond->signalAndUnlock(cmd->lock);
     }
     return result;
 }

 /* static */
 SyncThread* SyncThread::get() {
     return sGlobalSyncThread()->syncThreadPtr();
 }
	/*
	* Copyright (C) 2016 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 "SyncThread.h"

	#include "base/System.h"
	#include "base/Thread.h"
	#include "OpenGLESDispatch/OpenGLDispatchLoader.h"
	#include "host-common/crash_reporter.h"
	#include "host-common/sync_device.h"

	#ifndef _MSC_VER
	#include <sys/time.h>
	#endif
	#include <memory>

	#define DEBUG 0

	#if DEBUG

	static uint64_t curr_ms() {
	struct timeval tv;
	gettimeofday(&tv, NULL);
	return tv.tv_usec / 1000 + tv.tv_sec * 1000;
	}

	#define DPRINT(fmt, ...) do { \
	if (!VERBOSE_CHECK(syncthreads)) VERBOSE_ENABLE(syncthreads); \
	VERBOSE_TID_FUNCTION_DPRINT(syncthreads, "@ time=%llu: " fmt, curr_ms(), ##__VA_ARGS__); \
	} while(0)

	#else

	#define DPRINT(...)

	#endif

	// The single global sync thread instance.
	class GlobalSyncThread {
	public:
	GlobalSyncThread() = default;

	SyncThread* syncThreadPtr() { return &mSyncThread; }

	private:
	SyncThread mSyncThread;
	};

	static GlobalSyncThread* sGlobalSyncThread() {
	static GlobalSyncThread* t = new GlobalSyncThread;
	return t;
	}

	static const uint32_t kTimelineInterval = 1;
	static const uint64_t kDefaultTimeoutNsecs = 5ULL * 1000ULL * 1000ULL * 1000ULL;
	static const uint64_t kNumWorkerThreads = 1u;

	SyncThread::SyncThread()
	: android::base::Thread(android::base::ThreadFlags::MaskSignals, 512 * 1024),
	mWorkerThreadPool(kNumWorkerThreads, [this](SyncThreadCmd&& cmd) {
	doSyncThreadCmd(&cmd);
	}) {
	this->start();
	mWorkerThreadPool.start();
	initSyncContext();
	}

	SyncThread::~SyncThread() {
	cleanup();
	}

	void SyncThread::triggerWait(FenceSync* fenceSync,
	uint64_t timeline) {
	DPRINT("fenceSyncInfo=0x%llx timeline=0x%lx ...",
	fenceSync, timeline);
	SyncThreadCmd to_send;
	to_send.opCode = SYNC_THREAD_WAIT;
	to_send.fenceSync = fenceSync;
	to_send.timeline = timeline;
	DPRINT("opcode=%u", to_send.opCode);
	sendAsync(to_send);
	DPRINT("exit");
	}

	void SyncThread::triggerWaitVk(VkFence vkFence, uint64_t timeline) {
	DPRINT("fenceSyncInfo=0x%llx timeline=0x%lx ...", fenceSync, timeline);
	SyncThreadCmd to_send;
	to_send.opCode = SYNC_THREAD_WAIT_VK;
	to_send.vkFence = vkFence;
	to_send.timeline = timeline;
	DPRINT("opcode=%u", to_send.opCode);
	sendAsync(to_send);
	DPRINT("exit");
	}

	void SyncThread::triggerBlockedWaitNoTimeline(FenceSync* fenceSync) {
	DPRINT("fenceSyncInfo=0x%llx ...", fenceSync);
	SyncThreadCmd to_send;
	to_send.opCode = SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE;
	to_send.fenceSync = fenceSync;
	DPRINT("opcode=%u", to_send.opCode);
	sendAndWaitForResult(to_send);
	DPRINT("exit");
	}

	void SyncThread::cleanup() {
	DPRINT("enter");
	SyncThreadCmd to_send;
	to_send.opCode = SYNC_THREAD_EXIT;
	sendAndWaitForResult(to_send);
	DPRINT("signal");
	mLock.lock();
	mExiting = true;
	mCv.signalAndUnlock(&mLock);
	DPRINT("exit");
	}

	// Private methods below////////////////////////////////////////////////////////

	void SyncThread::initSyncContext() {
	DPRINT("enter");
	SyncThreadCmd to_send;
	to_send.opCode = SYNC_THREAD_INIT;
	sendAndWaitForResult(to_send);
	DPRINT("exit");
	}

	intptr_t SyncThread::main() {
	DPRINT("in sync thread");
	mLock.lock();
	mCv.wait(&mLock, [this] { return mExiting; });

	mWorkerThreadPool.done();
	mWorkerThreadPool.join();
	DPRINT("exited sync thread");
	return 0;
	}

	int SyncThread::sendAndWaitForResult(SyncThreadCmd& cmd) {
	DPRINT("send with opcode=%d", cmd.opCode);
	android::base::Lock lock;
	android::base::ConditionVariable cond;
	android::base::Optional<int> result = android::base::kNullopt;
	cmd.lock = &lock;
	cmd.cond = &cond;
	cmd.result = &result;

	lock.lock();
	mWorkerThreadPool.enqueue(std::move(cmd));
	cond.wait(&lock, [&result] { return result.hasValue(); });

	DPRINT("result=%d", *result);
	return *result;
	}

	void SyncThread::sendAsync(SyncThreadCmd& cmd) {
	DPRINT("send with opcode=%u fenceSyncInfo=0x%llx",
	cmd.opCode, cmd.fenceSync);
	mWorkerThreadPool.enqueue(std::move(cmd));
	}

	void SyncThread::doSyncContextInit() {
	const EGLDispatch* egl = emugl::LazyLoadedEGLDispatch::get();

	mDisplay = egl->eglGetDisplay(EGL_DEFAULT_DISPLAY);
	int eglMaj, eglMin;
	egl->eglInitialize(mDisplay, &eglMaj , &eglMin);

	const EGLint configAttribs[] = {
	EGL_SURFACE_TYPE, EGL_PBUFFER_BIT,
	EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
	EGL_RED_SIZE, 8,
	EGL_GREEN_SIZE, 8,
	EGL_BLUE_SIZE, 8,
	EGL_NONE,
	};

	EGLint nConfigs;
	EGLConfig config;

	egl->eglChooseConfig(mDisplay, configAttribs, &config, 1, &nConfigs);

	const EGLint pbufferAttribs[] = {
	EGL_WIDTH, 1,
	EGL_HEIGHT, 1,
	EGL_NONE,
	};

	mSurface =
	egl->eglCreatePbufferSurface(mDisplay, config, pbufferAttribs);

	const EGLint contextAttribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
	mContext = egl->eglCreateContext(mDisplay, config, EGL_NO_CONTEXT, contextAttribs);

	egl->eglMakeCurrent(mDisplay, mSurface, mSurface, mContext);
	}

	void SyncThread::doSyncWait(SyncThreadCmd* cmd) {
	DPRINT("enter");

	FenceSync* fenceSync =
	FenceSync::getFromHandle((uint64_t)(uintptr_t)cmd->fenceSync);

	if (!fenceSync) {
	emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);
	return;
	}

	EGLint wait_result = 0x0;

	DPRINT("wait on sync obj: %p", cmd->fenceSync);
	wait_result = cmd->fenceSync->wait(kDefaultTimeoutNsecs);

	DPRINT("done waiting, with wait result=0x%x. "
	"increment timeline (and signal fence)",
	wait_result);

	if (wait_result != EGL_CONDITION_SATISFIED_KHR) {
	DPRINT("error: eglClientWaitSync abnormal exit 0x%x. sync handle 0x%llx\n",
	wait_result, (unsigned long long)cmd->fenceSync);
	}

	DPRINT("issue timeline increment");

	// We always unconditionally increment timeline at this point, even
	// if the call to eglClientWaitSync returned abnormally.
	// There are three cases to consider:
	// - EGL_CONDITION_SATISFIED_KHR: either the sync object is already
	// signaled and we need to increment this timeline immediately, or
	// we have waited until the object is signaled, and then
	// we increment the timeline.
	// - EGL_TIMEOUT_EXPIRED_KHR: the fence command we put in earlier
	// in the OpenGL stream is not actually ever signaled, and we
	// end up blocking in the above eglClientWaitSyncKHR call until
	// our timeout runs out. In this case, provided we have waited
	// for \|kDefaultTimeoutNsecs\|, the guest will have received all
	// relevant error messages about fence fd's not being signaled
	// in time, so we are properly emulating bad behavior even if
	// we now increment the timeline.
	// - EGL_FALSE (error): chances are, the underlying EGL implementation
	// on the host doesn't actually support fence objects. In this case,
	// we should fail safe: 1) It must be only very old or faulty
	// graphics drivers / GPU's that don't support fence objects.
	// 2) The consequences of signaling too early are generally, out of
	// order frames and scrambled textures in some apps. But, not
	// incrementing the timeline means that the app's rendering freezes.
	// So, despite the faulty GPU driver, not incrementing is too heavyweight a response.

	emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);
	FenceSync::incrementTimelineAndDeleteOldFences();

	DPRINT("done timeline increment");

	DPRINT("exit");
	}

	int SyncThread::doSyncWaitVk(SyncThreadCmd* cmd) {
	DPRINT("enter");

	auto decoder = goldfish_vk::VkDecoderGlobalState::get();
	auto result = decoder->waitForFence(cmd->vkFence, kDefaultTimeoutNsecs);
	if (result == VK_TIMEOUT) {
	fprintf(stderr, "SyncThread::%s: SYNC_WAIT_VK timeout: vkFence=%p\n",
	__func__, cmd->vkFence);
	} else if (result != VK_SUCCESS) {
	fprintf(stderr, "SyncThread::%s: SYNC_WAIT_VK error: %d vkFence=%p\n",
	__func__, result, cmd->vkFence);
	}

	DPRINT("issue timeline increment");

	// We always unconditionally increment timeline at this point, even
	// if the call to vkWaitForFences returned abnormally.
	// See comments in \|doSyncWait\| about the rationale.
	emugl::emugl_sync_timeline_inc(cmd->timeline, kTimelineInterval);

	DPRINT("done timeline increment");

	DPRINT("exit");
	return result;
	}

	void SyncThread::doSyncBlockedWaitNoTimeline(SyncThreadCmd* cmd) {
	DPRINT("enter");

	FenceSync* fenceSync =
	FenceSync::getFromHandle((uint64_t)(uintptr_t)cmd->fenceSync);

	if (!fenceSync) {
	return;
	}

	EGLint wait_result = 0x0;

	DPRINT("wait on sync obj: %p", cmd->fenceSync);
	wait_result = cmd->fenceSync->wait(kDefaultTimeoutNsecs);

	DPRINT("done waiting, with wait result=0x%x. "
	"increment timeline (and signal fence)",
	wait_result);

	if (wait_result != EGL_CONDITION_SATISFIED_KHR) {
	fprintf(stderr, "error: eglClientWaitSync abnormal exit 0x%x %p\n",
	wait_result, cmd->fenceSync);
	}
	}

	void SyncThread::doExit() {

	if (mContext == EGL_NO_CONTEXT) return;

	const EGLDispatch* egl = emugl::LazyLoadedEGLDispatch::get();

	egl->eglMakeCurrent(mDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
	egl->eglDestroyContext(mDisplay, mContext);
	egl->eglDestroySurface(mDisplay, mContext);
	mContext = EGL_NO_CONTEXT;
	mSurface = EGL_NO_SURFACE;
	}

	int SyncThread::doSyncThreadCmd(SyncThreadCmd* cmd) {
	#if DEBUG
	thread_local static auto threadId = android::base::getCurrentThreadId();
	thread_local static size_t numCommands = 0U;
	DPRINT("threadId = %lu numCommands = %lu cmd = %p", threadId, ++numCommands,
	cmd);
	#endif // DEBUG

	int result = 0;
	switch (cmd->opCode) {
	case SYNC_THREAD_INIT:
	DPRINT("exec SYNC_THREAD_INIT");
	doSyncContextInit();
	break;
	case SYNC_THREAD_WAIT:
	DPRINT("exec SYNC_THREAD_WAIT");
	doSyncWait(cmd);
	break;
	case SYNC_THREAD_WAIT_VK:
	DPRINT("exec SYNC_THREAD_WAIT_VK");
	result = doSyncWaitVk(cmd);
	break;
	case SYNC_THREAD_EXIT:
	DPRINT("exec SYNC_THREAD_EXIT");
	doExit();
	break;
	case SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE:
	DPRINT("exec SYNC_THREAD_BLOCKED_WAIT_NO_TIMELINE");
	doSyncBlockedWaitNoTimeline(cmd);
	break;
	}

	bool need_reply = cmd->lock != nullptr && cmd->cond != nullptr;
	if (need_reply) {
	cmd->lock->lock();
	*cmd->result = android::base::makeOptional(result);
	cmd->cond->signalAndUnlock(cmd->lock);
	}
	return result;
	}

	/* static */
	SyncThread* SyncThread::get() {
	return sGlobalSyncThread()->syncThreadPtr();
	}