Vulkan: functionally complete worker thread

include/platform/FeaturesVk.h

@@ -343,6 +343,13 @@ struct FeaturesVk : FeatureSetBase
         "Enable parallel processing and submission of Vulkan commands in worker thread", &members,
         "http://anglebug.com/4324"};
 
+    // Enable parallel thread execution when enableCommandProcessingThread is enabled.
+    // Currently off by default.
+    Feature asynchronousCommandProcessing = {"asynchronous_command_processing",
+                                             FeatureCategory::VulkanFeatures,
+                                             "Enable/Disable parallel processing of worker thread",
+                                             &members, "http://anglebug.com/4324"};
+
     // Whether the VkDevice supports the VK_KHR_shader_float16_int8 extension and has the
     // shaderFloat16 feature.
     Feature supportsShaderFloat16 = {"supports_shader_float16", FeatureCategory::VulkanFeatures,

src/libANGLE/renderer/vulkan/CommandProcessor.cpp

@@ -8,12 +8,145 @@
 //
 
 #include "libANGLE/renderer/vulkan/CommandProcessor.h"
+#include "libANGLE/renderer/vulkan/RendererVk.h"
 #include "libANGLE/trace.h"
 
 namespace rx
 {
+namespace
+{
+constexpr size_t kInFlightCommandsLimit = 100u;
+constexpr bool kOutputVmaStatsString    = false;
+
+void InitializeSubmitInfo(VkSubmitInfo *submitInfo,
+                          const vk::PrimaryCommandBuffer &commandBuffer,
+                          const std::vector<VkSemaphore> &waitSemaphores,
+                          std::vector<VkPipelineStageFlags> *waitSemaphoreStageMasks,
+                          const vk::Semaphore *signalSemaphore)
+{
+    // Verify that the submitInfo has been zero'd out.
+    ASSERT(submitInfo->signalSemaphoreCount == 0);
+
+    submitInfo->sType              = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+    submitInfo->commandBufferCount = commandBuffer.valid() ? 1 : 0;
+    submitInfo->pCommandBuffers    = commandBuffer.ptr();
+
+    if (waitSemaphoreStageMasks->size() < waitSemaphores.size())
+    {
+        waitSemaphoreStageMasks->resize(waitSemaphores.size(), VK_PIPELINE_STAGE_ALL_COMMANDS_BIT);
+    }
+
+    submitInfo->waitSemaphoreCount = static_cast<uint32_t>(waitSemaphores.size());
+    submitInfo->pWaitSemaphores    = waitSemaphores.data();
+    submitInfo->pWaitDstStageMask  = waitSemaphoreStageMasks->data();
+
+    if (signalSemaphore)
+    {
+        submitInfo->signalSemaphoreCount = 1;
+        submitInfo->pSignalSemaphores    = signalSemaphore->ptr();
+    }
+    else
+    {
+        submitInfo->signalSemaphoreCount = 0;
+        submitInfo->pSignalSemaphores    = nullptr;
+    }
+}
+}  // namespace
+
 namespace vk
 {
+void CommandProcessorTask::initTask()
+{
+    mTask                  = CustomTask::Invalid;
+    mContextVk             = nullptr;
+    mRenderPass            = nullptr;
+    mCommandBuffer         = nullptr;
+    mSemaphore             = nullptr;
+    mOneOffFence           = nullptr;
+    mOneOffCommandBufferVk = VK_NULL_HANDLE;
+}
+
+// CommandProcessorTask implementation
+void CommandProcessorTask::initProcessCommands(ContextVk *contextVk,
+                                               CommandBufferHelper *commandBuffer,
+                                               vk::RenderPass *renderPass)
+{
+    mTask          = vk::CustomTask::ProcessCommands;
+    mContextVk     = contextVk;
+    mCommandBuffer = commandBuffer;
+    mRenderPass    = renderPass;
+}
+
+void CommandProcessorTask::initPresent(egl::ContextPriority priority, VkPresentInfoKHR presentInfo)
+{
+    mTask        = vk::CustomTask::Present;
+    mPresentInfo = presentInfo;
+    mPriority    = priority;
+}
+
+void CommandProcessorTask::initFinishToSerial(Serial serial)
+{
+    // Note: sometimes the serial is not valid and that's okay, the finish will early exit in the
+    // TaskProcessor::finishToSerial
+    mTask   = vk::CustomTask::FinishToSerial;
+    mSerial = serial;
+}
+
+void CommandProcessorTask::initFlushAndQueueSubmit(
+    std::vector<VkSemaphore> &&waitSemaphores,
+    std::vector<VkPipelineStageFlags> &&waitSemaphoreStageMasks,
+    const vk::Semaphore *semaphore,
+    egl::ContextPriority priority,
+    vk::GarbageList &&currentGarbage,
+    vk::ResourceUseList &&currentResources)
+{
+    mTask                    = vk::CustomTask::FlushAndQueueSubmit;
+    mWaitSemaphores          = std::move(waitSemaphores);
+    mWaitSemaphoreStageMasks = std::move(waitSemaphoreStageMasks);
+    mSemaphore               = semaphore;
+    mGarbage                 = std::move(currentGarbage);
+    mResourceUseList         = std::move(currentResources);
+    mPriority                = priority;
+}
+
+void CommandProcessorTask::initOneOffQueueSubmit(VkCommandBuffer oneOffCommandBufferVk,
+                                                 egl::ContextPriority priority,
+                                                 const vk::Fence *fence)
+{
+    mTask                  = vk::CustomTask::OneOffQueueSubmit;
+    mOneOffCommandBufferVk = oneOffCommandBufferVk;
+    mOneOffFence           = fence;
+    mPriority              = priority;
+}
+
+CommandProcessorTask &CommandProcessorTask::operator=(CommandProcessorTask &&rhs)
+{
+    if (this == &rhs)
+    {
+        return *this;
+    }
+
+    mContextVk     = rhs.mContextVk;
+    mRenderPass    = rhs.mRenderPass;
+    mCommandBuffer = rhs.mCommandBuffer;
+    std::swap(mTask, rhs.mTask);
+    std::swap(mWaitSemaphores, rhs.mWaitSemaphores);
+    std::swap(mWaitSemaphoreStageMasks, rhs.mWaitSemaphoreStageMasks);
+    mSemaphore   = rhs.mSemaphore;
+    mOneOffFence = rhs.mOneOffFence;
+    std::swap(mGarbage, rhs.mGarbage);
+    std::swap(mSerial, rhs.mSerial);
+    std::swap(mPresentInfo, rhs.mPresentInfo);
+    std::swap(mPriority, rhs.mPriority);
+    std::swap(mResourceUseList, rhs.mResourceUseList);
+    mOneOffCommandBufferVk = rhs.mOneOffCommandBufferVk;
+
+    // clear rhs now that everything has moved.
+    rhs.initTask();
+
+    return *this;
+}
+
 // CommandBatch implementation.
 CommandBatch::CommandBatch() = default;
 
@@ -39,67 +172,612 @@ void CommandBatch::destroy(VkDevice device)
     commandPool.destroy(device);
     fence.reset(device);
 }
-}  // namespace vk
 
-CommandProcessor::CommandProcessor() : mWorkerThreadIdle(true) {}
+// TaskProcessor implementation.
+TaskProcessor::TaskProcessor() = default;
+
+TaskProcessor::~TaskProcessor() = default;
+
+void TaskProcessor::destroy(VkDevice device)
+{
+    mPrimaryCommandPool.destroy(device);
+    ASSERT(mInFlightCommands.empty() && mGarbageQueue.empty());
+}
+
+angle::Result TaskProcessor::init(vk::Context *context, std::thread::id threadId)
+{
+    mThreadId = threadId;
+
+    // Initialize the command pool now that we know the queue family index.
+    ANGLE_TRY(mPrimaryCommandPool.init(context, context->getRenderer()->getQueueFamilyIndex()));
+
+    return angle::Result::Continue;
+}
+
+angle::Result TaskProcessor::checkCompletedCommands(vk::Context *context)
+{
+    ANGLE_TRACE_EVENT0("gpu.angle", "TaskProcessor::checkCompletedCommands");
+    VkDevice device        = context->getDevice();
+    RendererVk *rendererVk = context->getRenderer();
+
+    int finishedCount = 0;
+
+    for (vk::CommandBatch &batch : mInFlightCommands)
+    {
+        VkResult result = batch.fence.get().getStatus(device);
+        if (result == VK_NOT_READY)
+        {
+            break;
+        }
+        ANGLE_VK_TRY(context, result);
+
+        rendererVk->onCompletedSerial(batch.serial);
+
+        rendererVk->resetSharedFence(&batch.fence);
+
+        ANGLE_TRACE_EVENT0("gpu.angle", "command buffer recycling");
+        batch.commandPool.destroy(device);
+        ANGLE_TRY(releasePrimaryCommandBuffer(context, std::move(batch.primaryCommands)));
+        ++finishedCount;
+    }
+
+    if (finishedCount > 0)
+    {
+        auto beginIter = mInFlightCommands.begin();
+        mInFlightCommands.erase(beginIter, beginIter + finishedCount);
+    }
+
+    Serial lastCompleted = rendererVk->getLastCompletedQueueSerial();
+
+    size_t freeIndex = 0;
+    for (; freeIndex < mGarbageQueue.size(); ++freeIndex)
+    {
+        vk::GarbageAndSerial &garbageList = mGarbageQueue[freeIndex];
+        if (garbageList.getSerial() <= lastCompleted)
+        {
+            for (vk::GarbageObject &garbage : garbageList.get())
+            {
+                garbage.destroy(rendererVk);
+            }
+        }
+        else
+        {
+            break;
+        }
+    }
+
+    // Remove the entries from the garbage list - they should be ready to go.
+    if (freeIndex > 0)
+    {
+        mGarbageQueue.erase(mGarbageQueue.begin(), mGarbageQueue.begin() + freeIndex);
+    }
+
+    return angle::Result::Continue;
+}
+
+angle::Result TaskProcessor::releaseToCommandBatch(vk::Context *context,
+                                                   vk::PrimaryCommandBuffer &&commandBuffer,
+                                                   vk::CommandPool *commandPool,
+                                                   vk::CommandBatch *batch)
+{
+    batch->primaryCommands = std::move(commandBuffer);
+
+    if (commandPool->valid())
+    {
+        batch->commandPool = std::move(*commandPool);
+        // Recreate CommandPool
+        VkCommandPoolCreateInfo poolInfo = {};
+        poolInfo.sType                   = VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO;
+        poolInfo.flags                   = VK_COMMAND_POOL_CREATE_TRANSIENT_BIT;
+        poolInfo.queueFamilyIndex        = context->getRenderer()->getQueueFamilyIndex();
+
+        ANGLE_VK_TRY(context, commandPool->init(context->getDevice(), poolInfo));
+    }
+
+    return angle::Result::Continue;
+}
+
+angle::Result TaskProcessor::allocatePrimaryCommandBuffer(
+    vk::Context *context,
+    vk::PrimaryCommandBuffer *commandBufferOut)
+{
+    return mPrimaryCommandPool.allocate(context, commandBufferOut);
+}
+
+angle::Result TaskProcessor::releasePrimaryCommandBuffer(vk::Context *context,
+                                                         vk::PrimaryCommandBuffer &&commandBuffer)
+{
+    ASSERT(mPrimaryCommandPool.valid());
+    return mPrimaryCommandPool.collect(context, std::move(commandBuffer));
+}
+
+void TaskProcessor::handleDeviceLost(vk::Context *context)
+{
+    VkDevice device = context->getDevice();
+
+    for (vk::CommandBatch &batch : mInFlightCommands)
+    {
+        // On device loss we need to wait for fence to be signaled before destroying it
+        VkResult status =
+            batch.fence.get().wait(device, context->getRenderer()->getMaxFenceWaitTimeNs());
+        // If the wait times out, it is probably not possible to recover from lost device
+        ASSERT(status == VK_SUCCESS || status == VK_ERROR_DEVICE_LOST);
+
+        // On device lost, here simply destroy the CommandBuffer, it will be fully cleared later by
+        // CommandPool::destroy
+        batch.primaryCommands.destroy(device);
 
-void CommandProcessor::queueCommands(const vk::CommandProcessorTask &commands)
+        batch.commandPool.destroy(device);
+        batch.fence.reset(device);
+    }
+    mInFlightCommands.clear();
+}
+
+// If there are any inflight commands worker will look for fence that corresponds to the request
+// serial or the last available fence and wait on that fence. Will then do necessary cleanup work.
+// This can cause the worker thread to block.
+// TODO: https://issuetracker.google.com/issues/170312581 - A more optimal solution might be to do
+// the wait in CommandProcessor rather than the worker thread. That would require protecting access
+// to mInFlightCommands
+angle::Result TaskProcessor::finishToSerial(vk::Context *context, Serial serial)
 {
-    ANGLE_TRACE_EVENT0("gpu.angle", "CommandProcessor::queueCommands");
-    std::lock_guard<std::mutex> queueLock(mWorkerMutex);
-    ASSERT(commands.commandBuffer == nullptr || !commands.commandBuffer->empty());
-    mCommandsQueue.push(commands);
-    mWorkAvailableCondition.notify_one();
+    RendererVk *rendererVk = context->getRenderer();
+    uint64_t timeout       = rendererVk->getMaxFenceWaitTimeNs();
+
+    if (mInFlightCommands.empty())
+    {
+        // No outstanding work, nothing to wait for.
+        return angle::Result::Continue;
+    }
+
+    // Find the first batch with serial equal to or bigger than given serial (note that
+    // the batch serials are unique, otherwise upper-bound would have been necessary).
+    size_t batchIndex = mInFlightCommands.size() - 1;
+    for (size_t i = 0; i < mInFlightCommands.size(); ++i)
+    {
+        if (mInFlightCommands[i].serial >= serial)
+        {
+            batchIndex = i;
+            break;
+        }
+    }
+    const vk::CommandBatch &batch = mInFlightCommands[batchIndex];
+
+    // Wait for it finish
+    VkDevice device = context->getDevice();
+    ANGLE_VK_TRY(context, batch.fence.get().wait(device, timeout));
+
+    // Clean up finished batches.
+    return checkCompletedCommands(context);
 }
 
-void CommandProcessor::processCommandProcessorTasks()
+VkResult TaskProcessor::present(VkQueue queue, const VkPresentInfoKHR &presentInfo)
 {
+    ANGLE_TRACE_EVENT0("gpu.angle", "vkQueuePresentKHR");
+    return vkQueuePresentKHR(queue, &presentInfo);
+}
+
+angle::Result TaskProcessor::submitFrame(vk::Context *context,
+                                         VkQueue queue,
+                                         const VkSubmitInfo &submitInfo,
+                                         const vk::Shared<vk::Fence> &sharedFence,
+                                         vk::GarbageList *currentGarbage,
+                                         vk::CommandPool *commandPool,
+                                         vk::PrimaryCommandBuffer &&commandBuffer,
+                                         const Serial &queueSerial)
+{
+    ASSERT(std::this_thread::get_id() == mThreadId);
+    ANGLE_TRACE_EVENT0("gpu.angle", "TaskProcessor::submitFrame");
+
+    VkDevice device = context->getDevice();
+
+    vk::DeviceScoped<vk::CommandBatch> scopedBatch(device);
+    vk::CommandBatch &batch = scopedBatch.get();
+    batch.fence.copy(device, sharedFence);
+    batch.serial = queueSerial;
+
+    ANGLE_TRY(queueSubmit(context, queue, submitInfo, &batch.fence.get()));
+
+    if (!currentGarbage->empty())
+    {
+        mGarbageQueue.emplace_back(std::move(*currentGarbage), queueSerial);
+    }
+
+    // Store the primary CommandBuffer and command pool used for secondary CommandBuffers
+    // in the in-flight list.
+    ANGLE_TRY(releaseToCommandBatch(context, std::move(commandBuffer), commandPool, &batch));
+
+    mInFlightCommands.emplace_back(scopedBatch.release());
+
+    ANGLE_TRY(checkCompletedCommands(context));
+
+    // CPU should be throttled to avoid mInFlightCommands from growing too fast. Important for
+    // off-screen scenarios.
+    while (mInFlightCommands.size() > kInFlightCommandsLimit)
+    {
+        ANGLE_TRY(finishToSerial(context, mInFlightCommands[0].serial));
+    }
+
+    return angle::Result::Continue;
+}
+
+vk::Shared<vk::Fence> TaskProcessor::getLastSubmittedFenceWithLock(VkDevice device) const
+{
+    vk::Shared<vk::Fence> fence;
+    // Note: this must be called when the work queue is empty and while holding mWorkerMutex to
+    // ensure that worker isn't touching mInFlightCommands
+    if (!mInFlightCommands.empty())
+    {
+        fence.copy(device, mInFlightCommands.back().fence);
+    }
+
+    return fence;
+}
+
+angle::Result TaskProcessor::queueSubmit(vk::Context *context,
+                                         VkQueue queue,
+                                         const VkSubmitInfo &submitInfo,
+                                         const vk::Fence *fence)
+{
+    ASSERT(std::this_thread::get_id() == mThreadId);
+    if (kOutputVmaStatsString)
+    {
+        context->getRenderer()->outputVmaStatString();
+    }
+
+    // Don't need a QueueMutex since all queue accesses are serialized through the worker.
+    VkFence handle = fence ? fence->getHandle() : VK_NULL_HANDLE;
+    ANGLE_VK_TRY(context, vkQueueSubmit(queue, 1, &submitInfo, handle));
+
+    return angle::Result::Continue;
+}
+
+void CommandProcessor::handleError(VkResult errorCode,
+                                   const char *file,
+                                   const char *function,
+                                   unsigned int line)
+{
+    ASSERT(errorCode != VK_SUCCESS);
+
+    std::stringstream errorStream;
+    errorStream << "Internal Vulkan error (" << errorCode << "): " << VulkanResultString(errorCode)
+                << ".";
+
+    if (errorCode == VK_ERROR_DEVICE_LOST)
+    {
+        WARN() << errorStream.str();
+        handleDeviceLost();
+    }
+
+    std::lock_guard<std::mutex> queueLock(mErrorMutex);
+    vk::Error error = {errorCode, file, function, line};
+    mErrors.emplace(error);
+}
+
+CommandProcessor::CommandProcessor(RendererVk *renderer)
+    : vk::Context(renderer),
+      mWorkerThreadIdle(false),
+      mCommandProcessorLastSubmittedSerial(mQueueSerialFactory.generate()),
+      mCommandProcessorCurrentQueueSerial(mQueueSerialFactory.generate())
+{
+    std::lock_guard<std::mutex> queueLock(mErrorMutex);
+    while (!mErrors.empty())
+    {
+        mErrors.pop();
+    }
+}
+
+CommandProcessor::~CommandProcessor() = default;
+
+bool CommandProcessor::isRobustResourceInitEnabled() const
+{
+    // Unused for worker thread, just return false.
+    return false;
+}
+
+vk::Error CommandProcessor::getAndClearPendingError()
+{
+    std::lock_guard<std::mutex> queueLock(mErrorMutex);
+    vk::Error tmpError({VK_SUCCESS, nullptr, nullptr, 0});
+    if (!mErrors.empty())
+    {
+        tmpError = mErrors.front();
+        mErrors.pop();
+    }
+    return tmpError;
+}
+
+void CommandProcessor::queueCommand(vk::Context *context, vk::CommandProcessorTask *task)
+{
+    ANGLE_TRACE_EVENT0("gpu.angle", "CommandProcessor::queueCommand");
+    {
+        // Grab the worker mutex so that we put things on the queue in the same order as we give out
+        // serials.
+        std::lock_guard<std::mutex> queueLock(mWorkerMutex);
+
+        if (task->getTaskCommand() == vk::CustomTask::FlushAndQueueSubmit ||
+            task->getTaskCommand() == vk::CustomTask::OneOffQueueSubmit)
+        {
+            std::lock_guard<std::mutex> lock(mCommandProcessorQueueSerialMutex);
+            // Flush submits work, so give it the current serial and generate a new one.
+            Serial queueSerial = mCommandProcessorCurrentQueueSerial;
+            task->setQueueSerial(queueSerial);
+            mCommandProcessorLastSubmittedSerial = mCommandProcessorCurrentQueueSerial;
+            mCommandProcessorCurrentQueueSerial  = mQueueSerialFactory.generate();
+
+            task->getResourceUseList().releaseResourceUsesAndUpdateSerials(queueSerial);
+        }
+
+        mTasks.emplace(std::move(*task));
+        mWorkAvailableCondition.notify_one();
+    }
+
+    if (getRenderer()->getFeatures().asynchronousCommandProcessing.enabled)
+    {
+        return;
+    }
+
+    // parallel task processing disabled so wait for work to complete.
+    waitForWorkComplete(context);
+}
+
+void CommandProcessor::processTasks()
+{
+
+    while (true)
+    {
+        bool exitThread      = false;
+        angle::Result result = processTasksImpl(&exitThread);
+        if (exitThread)
+        {
+            // We are doing a controlled exit of the thread, break out of the while loop.
+            break;
+        }
+        if (result != angle::Result::Continue)
+        {
+            // TODO: https://issuetracker.google.com/issues/170311829 - follow-up on error handling
+            // ContextVk::commandProcessorSyncErrorsAndQueueCommand and WindowSurfaceVk::destroy
+            // do error processing, is anything required here? Don't think so, mostly need to
+            // continue the worker thread until it's been told to exit.
+            UNREACHABLE();
+        }
+    }
+}
+
+angle::Result CommandProcessor::processTasksImpl(bool *exitThread)
+{
+    // Initialization prior to work thread loop
+    ANGLE_TRY(mTaskProcessor.init(this, std::this_thread::get_id()));
+    // Allocate and begin primary command buffer
+    ANGLE_TRY(mTaskProcessor.allocatePrimaryCommandBuffer(this, &mPrimaryCommandBuffer));
+    VkCommandBufferBeginInfo beginInfo = {};
+    beginInfo.sType                    = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
+    beginInfo.flags                    = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+    beginInfo.pInheritanceInfo         = nullptr;
+
+    ANGLE_VK_TRY(this, mPrimaryCommandBuffer.begin(beginInfo));
+
     while (true)
     {
         std::unique_lock<std::mutex> lock(mWorkerMutex);
-        mWorkerIdleCondition.notify_one();
-        mWorkerThreadIdle = true;
-        // Only wake if notified and command queue is not empty
-        mWorkAvailableCondition.wait(lock, [this] { return !mCommandsQueue.empty(); });
-        mWorkerThreadIdle             = false;
-        vk::CommandProcessorTask task = mCommandsQueue.front();
-        mCommandsQueue.pop();
+        if (mTasks.empty())
+        {
+            mWorkerThreadIdle = true;
+            mWorkerIdleCondition.notify_all();
+            // Only wake if notified and command queue is not empty
+            mWorkAvailableCondition.wait(lock, [this] { return !mTasks.empty(); });
+        }
+        mWorkerThreadIdle = false;
+        vk::CommandProcessorTask task(std::move(mTasks.front()));
+        mTasks.pop();
         lock.unlock();
-        // Either both ptrs should be null or non-null
-        ASSERT((task.commandBuffer != nullptr && task.contextVk != nullptr) ||
-               (task.commandBuffer == nullptr && task.contextVk == nullptr));
-        // A work block with null ptrs signals worker thread to exit
-        if (task.commandBuffer == nullptr && task.contextVk == nullptr)
+
+        switch (task.getTaskCommand())
+        {
+            case vk::CustomTask::Exit:
+            {
+                ANGLE_TRY(mTaskProcessor.finishToSerial(this, Serial::Infinite()));
+                *exitThread = true;
+                // Shutting down so cleanup
+                mTaskProcessor.destroy(mRenderer->getDevice());
+                mCommandPool.destroy(mRenderer->getDevice());
+                mPrimaryCommandBuffer.destroy(mRenderer->getDevice());
+                mWorkerThreadIdle = true;
+                mWorkerIdleCondition.notify_one();
+                return angle::Result::Continue;
+            }
+            default:
+                ANGLE_TRY(processTask(&task));
+                break;
+        }
+    }
+
+    UNREACHABLE();
+    return angle::Result::Stop;
+}
+
+angle::Result CommandProcessor::processTask(vk::CommandProcessorTask *task)
+{
+    switch (task->getTaskCommand())
+    {
+        case vk::CustomTask::FlushAndQueueSubmit:
         {
+            // End command buffer
+            ANGLE_VK_TRY(this, mPrimaryCommandBuffer.end());
+            // 1. Create submitInfo
+            VkSubmitInfo submitInfo = {};
+            InitializeSubmitInfo(&submitInfo, mPrimaryCommandBuffer, task->getWaitSemaphores(),
+                                 &task->getWaitSemaphoreStageMasks(), task->getSemaphore());
+
+            // 2. Get shared submit fence. It's possible there are other users of this fence that
+            // must wait for the work to be submitted before waiting on the fence. Reset the fence
+            // immediately so we are sure to get a fresh one next time.
+            vk::Shared<vk::Fence> fence;
+            ANGLE_TRY(mRenderer->getNextSubmitFence(&fence, true));
+
+            // 3. Call submitFrame()
+            ANGLE_TRY(mTaskProcessor.submitFrame(
+                this, getRenderer()->getVkQueue(task->getPriority()), submitInfo, fence,
+                &task->getGarbage(), &mCommandPool, std::move(mPrimaryCommandBuffer),
+                task->getQueueSerial()));
+            // 4. Allocate & begin new primary command buffer
+            ANGLE_TRY(mTaskProcessor.allocatePrimaryCommandBuffer(this, &mPrimaryCommandBuffer));
+
+            VkCommandBufferBeginInfo beginInfo = {};
+            beginInfo.sType                    = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
+            beginInfo.flags                    = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+            beginInfo.pInheritanceInfo         = nullptr;
+            ANGLE_VK_TRY(this, mPrimaryCommandBuffer.begin(beginInfo));
+
+            // Free this local reference
+            getRenderer()->resetSharedFence(&fence);
+
+            ASSERT(task->getGarbage().empty());
             break;
         }
+        case vk::CustomTask::OneOffQueueSubmit:
+        {
+            VkSubmitInfo submitInfo = {};
+            submitInfo.sType        = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+            if (task->getOneOffCommandBufferVk() != VK_NULL_HANDLE)
+            {
+                submitInfo.commandBufferCount = 1;
+                submitInfo.pCommandBuffers    = &task->getOneOffCommandBufferVk();
+            }
 
-        ASSERT(!task.commandBuffer->empty());
-        // TODO: Will need some way to synchronize error reporting between threads
-        (void)(task.commandBuffer->flushToPrimary(task.contextVk, task.primaryCB));
-        ASSERT(task.commandBuffer->empty());
-        task.commandBuffer->releaseToContextQueue(task.contextVk);
+            // TODO: https://issuetracker.google.com/issues/170328907 - vkQueueSubmit should be
+            // owned by TaskProcessor to ensure proper synchronization
+            ANGLE_TRY(mTaskProcessor.queueSubmit(this,
+                                                 getRenderer()->getVkQueue(task->getPriority()),
+                                                 submitInfo, task->getOneOffFence()));
+            ANGLE_TRY(mTaskProcessor.checkCompletedCommands(this));
+            break;
+        }
+        case vk::CustomTask::FinishToSerial:
+        {
+            ANGLE_TRY(mTaskProcessor.finishToSerial(this, task->getQueueSerial()));
+            break;
+        }
+        case vk::CustomTask::Present:
+        {
+            VkResult result = mTaskProcessor.present(getRenderer()->getVkQueue(task->getPriority()),
+                                                     task->getPresentInfo());
+            if (ANGLE_UNLIKELY(result != VK_SUCCESS))
+            {
+                // Save the error so that we can handle it (e.g. VK_OUT_OF_DATE)
+                // Don't leave processing loop, don't consider errors from present to be fatal.
+                // TODO: https://issuetracker.google.com/issues/170329600 - This needs to improve to
+                // properly parallelize present
+                handleError(result, __FILE__, __FUNCTION__, __LINE__);
+            }
+            break;
+        }
+        case vk::CustomTask::ProcessCommands:
+        {
+            ASSERT(!task->getCommandBuffer()->empty());
+            ANGLE_TRY(task->getCommandBuffer()->flushToPrimary(
+                getRenderer()->getFeatures(), &mPrimaryCommandBuffer, task->getRenderPass()));
+            ASSERT(task->getCommandBuffer()->empty());
+            task->getCommandBuffer()->releaseToContextQueue(task->getContextVk());
+            break;
+        }
+        default:
+            UNREACHABLE();
+            break;
     }
+
+    return angle::Result::Continue;
 }
 
-void CommandProcessor::waitForWorkComplete()
+void CommandProcessor::waitForWorkComplete(vk::Context *context)
 {
     ANGLE_TRACE_EVENT0("gpu.angle", "CommandProcessor::waitForWorkerThreadIdle");
     std::unique_lock<std::mutex> lock(mWorkerMutex);
-    mWorkerIdleCondition.wait(lock,
-                              [this] { return (mCommandsQueue.empty() && mWorkerThreadIdle); });
+    mWorkerIdleCondition.wait(lock, [this] { return (mTasks.empty() && mWorkerThreadIdle); });
     // Worker thread is idle and command queue is empty so good to continue
-    lock.unlock();
+
+    if (!context)
+    {
+        return;
+    }
+
+    // Sync any errors to the context
+    while (hasPendingError())
+    {
+        vk::Error workerError = getAndClearPendingError();
+        if (workerError.mErrorCode != VK_SUCCESS)
+        {
+            context->handleError(workerError.mErrorCode, workerError.mFile, workerError.mFunction,
+                                 workerError.mLine);
+        }
+    }
 }
 
 void CommandProcessor::shutdown(std::thread *commandProcessorThread)
 {
-    waitForWorkComplete();
-    const vk::CommandProcessorTask endTask = vk::kEndCommandProcessorThread;
-    queueCommands(endTask);
+    vk::CommandProcessorTask endTask;
+    endTask.initTask(vk::CustomTask::Exit);
+    queueCommand(nullptr, &endTask);
+    waitForWorkComplete(nullptr);
     if (commandProcessorThread->joinable())
     {
         commandProcessorThread->join();
     }
 }
+
+// Return the fence for the last submit. This may mean waiting on the worker to process tasks to
+// actually get to the last submit
+vk::Shared<vk::Fence> CommandProcessor::getLastSubmittedFence() const
+{
+    ANGLE_TRACE_EVENT0("gpu.angle", "CommandProcessor::getLastSubmittedFence");
+    std::unique_lock<std::mutex> lock(mWorkerMutex);
+    mWorkerIdleCondition.wait(lock, [this] { return (mTasks.empty() && mWorkerThreadIdle); });
+
+    // Worker thread is idle and command queue is empty so good to continue
+
+    return mTaskProcessor.getLastSubmittedFenceWithLock(getDevice());
+}
+
+Serial CommandProcessor::getLastSubmittedSerial()
+{
+    std::lock_guard<std::mutex> lock(mCommandProcessorQueueSerialMutex);
+    return mCommandProcessorLastSubmittedSerial;
+}
+
+Serial CommandProcessor::getCurrentQueueSerial()
+{
+    std::lock_guard<std::mutex> lock(mCommandProcessorQueueSerialMutex);
+    return mCommandProcessorCurrentQueueSerial;
+}
+
+// Wait until all commands up to and including serial have been processed
+void CommandProcessor::finishToSerial(vk::Context *context, Serial serial)
+{
+    vk::CommandProcessorTask finishToSerial;
+    finishToSerial.initFinishToSerial(serial);
+    queueCommand(context, &finishToSerial);
+
+    // Wait until the worker is idle. At that point we know that the finishToSerial command has
+    // completed executing, including any associated state cleanup.
+    waitForWorkComplete(context);
+}
+
+void CommandProcessor::handleDeviceLost()
+{
+    ANGLE_TRACE_EVENT0("gpu.angle", "CommandProcessor::handleDeviceLost");
+    std::unique_lock<std::mutex> lock(mWorkerMutex);
+    mWorkerIdleCondition.wait(lock, [this] { return (mTasks.empty() && mWorkerThreadIdle); });
+
+    // Worker thread is idle and command queue is empty so good to continue
+    mTaskProcessor.handleDeviceLost(this);
+}
+
+void CommandProcessor::finishAllWork(vk::Context *context)
+{
+    // Wait for GPU work to finish
+    finishToSerial(context, Serial::Infinite());
+}
+
+}  // namespace vk
+
 }  // namespace rx

src/libANGLE/renderer/vulkan/CommandProcessor.h

@@ -17,27 +17,120 @@
 #include <thread>
 
 #include "common/vulkan/vk_headers.h"
+#include "libANGLE/renderer/vulkan/PersistentCommandPool.h"
 #include "libANGLE/renderer/vulkan/vk_helpers.h"
 
 namespace rx
 {
+class RendererVk;
+class CommandProcessor;
+
 namespace vk
 {
 // CommandProcessorTask is used to queue a task to the worker thread when
-//  enableCommandProcessingThread feature is true.
-// The typical task includes pointers in all values and the worker thread will
-//  process the SecondaryCommandBuffer commands in cbh into the primaryCB.
-// There is a special task in which all of the pointers are null that will trigger
-//  the worker thread to exit, and is sent when the renderer instance shuts down.
-struct CommandProcessorTask
+// enableCommandProcessingThread feature is true.
+// Issuing the CustomTask::Exit command will cause the worker thread to clean up it's resources and
+// shut down. This command is sent when the renderer instance shuts down. Custom tasks are:
+
+enum CustomTask
 {
-    ContextVk *contextVk;
-    // TODO: b/153666475 Removed primaryCB in threading phase2.
-    vk::PrimaryCommandBuffer *primaryCB;
-    CommandBufferHelper *commandBuffer;
+    Invalid = 0,
+    // Process SecondaryCommandBuffer commands into the primary CommandBuffer.
+    ProcessCommands,
+    // End the current command buffer and submit commands to the queue
+    FlushAndQueueSubmit,
+    // Submit custom command buffer, excludes some state management
+    OneOffQueueSubmit,
+    // Finish queue commands up to given serial value, process garbage
+    FinishToSerial,
+    // Execute QueuePresent
+    Present,
+    // Exit the command processor thread
+    Exit,
 };
 
-static const CommandProcessorTask kEndCommandProcessorThread = {nullptr, nullptr, nullptr};
+class CommandProcessorTask
+{
+  public:
+    CommandProcessorTask() { initTask(); }
+
+    void initTask();
+
+    void initTask(CustomTask command) { mTask = command; }
+
+    void initProcessCommands(ContextVk *contextVk,
+                             CommandBufferHelper *commandBuffer,
+                             vk::RenderPass *renderPass);
+
+    void initPresent(egl::ContextPriority priority, VkPresentInfoKHR presentInfo);
+
+    void initFinishToSerial(Serial serial);
+
+    void initFlushAndQueueSubmit(std::vector<VkSemaphore> &&waitSemaphores,
+                                 std::vector<VkPipelineStageFlags> &&waitSemaphoreStageMasks,
+                                 const vk::Semaphore *semaphore,
+                                 egl::ContextPriority priority,
+                                 vk::GarbageList &&currentGarbage,
+                                 vk::ResourceUseList &&currentResources);
+
+    void initOneOffQueueSubmit(VkCommandBuffer oneOffCommandBufferVk,
+                               egl::ContextPriority priority,
+                               const vk::Fence *fence);
+
+    CommandProcessorTask &operator=(CommandProcessorTask &&rhs);
+
+    CommandProcessorTask(CommandProcessorTask &&other) : CommandProcessorTask()
+    {
+        *this = std::move(other);
+    }
+
+    void setQueueSerial(Serial serial) { mSerial = serial; }
+    Serial getQueueSerial() const { return mSerial; }
+    vk::ResourceUseList &getResourceUseList() { return mResourceUseList; }
+    vk::CustomTask getTaskCommand() { return mTask; }
+    std::vector<VkSemaphore> &getWaitSemaphores() { return mWaitSemaphores; }
+    std::vector<VkPipelineStageFlags> &getWaitSemaphoreStageMasks()
+    {
+        return mWaitSemaphoreStageMasks;
+    }
+    const vk::Semaphore *getSemaphore() { return mSemaphore; }
+    vk::GarbageList &getGarbage() { return mGarbage; }
+    egl::ContextPriority getPriority() const { return mPriority; }
+    const VkCommandBuffer &getOneOffCommandBufferVk() const { return mOneOffCommandBufferVk; }
+    const vk::Fence *getOneOffFence() { return mOneOffFence; }
+    const VkPresentInfoKHR &getPresentInfo() const { return mPresentInfo; }
+    vk::RenderPass *getRenderPass() const { return mRenderPass; }
+    CommandBufferHelper *getCommandBuffer() const { return mCommandBuffer; }
+    ContextVk *getContextVk() const { return mContextVk; }
+
+  private:
+    CustomTask mTask;
+
+    // ProcessCommands
+    ContextVk *mContextVk;
+    vk::RenderPass *mRenderPass;
+    CommandBufferHelper *mCommandBuffer;
+
+    // Flush data
+    std::vector<VkSemaphore> mWaitSemaphores;
+    std::vector<VkPipelineStageFlags> mWaitSemaphoreStageMasks;
+    const vk::Semaphore *mSemaphore;
+    vk::GarbageList mGarbage;
+    vk::ResourceUseList mResourceUseList;
+
+    // FinishToSerial & Flush command data
+    Serial mSerial;
+
+    // Present command data
+    VkPresentInfoKHR mPresentInfo;
+
+    // Used by OneOffQueueSubmit
+    VkCommandBuffer mOneOffCommandBufferVk;
+    const vk::Fence *mOneOffFence;
+
+    // Flush, Present & QueueWaitIdle data
+    egl::ContextPriority mPriority;
+};
 
 struct CommandBatch final : angle::NonCopyable
 {
@@ -54,37 +147,139 @@ struct CommandBatch final : angle::NonCopyable
     vk::Shared<vk::Fence> fence;
     Serial serial;
 };
-}  // namespace vk
 
-class CommandProcessor : angle::NonCopyable
+class TaskProcessor : angle::NonCopyable
+{
+  public:
+    TaskProcessor();
+    ~TaskProcessor();
+
+    angle::Result init(vk::Context *context, std::thread::id threadId);
+    void destroy(VkDevice device);
+
+    angle::Result allocatePrimaryCommandBuffer(vk::Context *context,
+                                               vk::PrimaryCommandBuffer *commandBufferOut);
+    angle::Result releasePrimaryCommandBuffer(vk::Context *context,
+                                              vk::PrimaryCommandBuffer &&commandBuffer);
+
+    void clearAllGarbage(vk::Context *context);
+
+    angle::Result finishToSerial(vk::Context *context, Serial serial);
+
+    VkResult present(VkQueue queue, const VkPresentInfoKHR &presentInfo);
+
+    angle::Result submitFrame(vk::Context *context,
+                              VkQueue queue,
+                              const VkSubmitInfo &submitInfo,
+                              const vk::Shared<vk::Fence> &sharedFence,
+                              vk::GarbageList *currentGarbage,
+                              vk::CommandPool *commandPool,
+                              vk::PrimaryCommandBuffer &&commandBuffer,
+                              const Serial &queueSerial);
+    angle::Result queueSubmit(vk::Context *context,
+                              VkQueue queue,
+                              const VkSubmitInfo &submitInfo,
+                              const vk::Fence *fence);
+
+    vk::Shared<vk::Fence> getLastSubmittedFenceWithLock(VkDevice device) const;
+
+    // Check to see which batches have finished completion (forward progress for
+    // mLastCompletedQueueSerial, for example for when the application busy waits on a query
+    // result). It would be nice if we didn't have to expose this for QueryVk::getResult.
+    angle::Result checkCompletedCommands(vk::Context *context);
+
+    void handleDeviceLost(vk::Context *context);
+
+  private:
+    angle::Result releaseToCommandBatch(vk::Context *context,
+                                        vk::PrimaryCommandBuffer &&commandBuffer,
+                                        vk::CommandPool *commandPool,
+                                        vk::CommandBatch *batch);
+
+    vk::GarbageQueue mGarbageQueue;
+    std::vector<vk::CommandBatch> mInFlightCommands;
+
+    // Keeps a free list of reusable primary command buffers.
+    vk::PersistentCommandPool mPrimaryCommandPool;
+    std::thread::id mThreadId;
+};
+
+class CommandProcessor : public vk::Context
 {
   public:
-    CommandProcessor();
-    ~CommandProcessor() = default;
-
-    // Main worker loop that should be launched in its own thread. The
-    //  loop waits for work to be submitted from a separate thread.
-    void processCommandProcessorTasks();
-    // Called asynchronously from workLoop() thread to queue work that is
-    //  then processed by the workLoop() thread
-    void queueCommands(const vk::CommandProcessorTask &commands);
-    // Used by separate thread to wait for worker thread to complete all
-    //  outstanding work.
-    void waitForWorkComplete();
-    // Stop the command processor loop
+    CommandProcessor(RendererVk *renderer);
+    ~CommandProcessor() override;
+
+    void handleError(VkResult result,
+                     const char *file,
+                     const char *function,
+                     unsigned int line) override;
+
+    bool isRobustResourceInitEnabled() const override;
+
+    // Entry point for command processor thread, calls processTasksImpl to do the
+    // work. called by RendererVk::initialization on main thread
+    void processTasks();
+
+    // Called asynchronously from main thread to queue work that is then processed by the worker
+    // thread
+    void queueCommand(vk::Context *context, vk::CommandProcessorTask *task);
+
+    // Used by main thread to wait for worker thread to complete all outstanding work.
+    void waitForWorkComplete(vk::Context *context);
+    Serial getCurrentQueueSerial();
+    Serial getLastSubmittedSerial();
+
+    // Wait until desired serial has been processed.
+    void finishToSerial(vk::Context *context, Serial serial);
+
+    vk::Shared<vk::Fence> getLastSubmittedFence() const;
+    void handleDeviceLost();
+
+    bool hasPendingError() const
+    {
+        std::lock_guard<std::mutex> queueLock(mErrorMutex);
+        return !mErrors.empty();
+    }
+    vk::Error getAndClearPendingError();
+
+    // Stop the command processor thread
     void shutdown(std::thread *commandProcessorThread);
 
+    void finishAllWork(vk::Context *context);
+
   private:
-    std::queue<vk::CommandProcessorTask> mCommandsQueue;
-    std::mutex mWorkerMutex;
+    // Command processor thread, called by processTasks. The loop waits for work to
+    // be submitted from a separate thread.
+    angle::Result processTasksImpl(bool *exitThread);
+
+    // Command processor thread, process a task
+    angle::Result processTask(vk::CommandProcessorTask *task);
+
+    std::queue<vk::CommandProcessorTask> mTasks;
+    mutable std::mutex mWorkerMutex;
     // Signal worker thread when work is available
     std::condition_variable mWorkAvailableCondition;
     // Signal main thread when all work completed
-    std::condition_variable mWorkerIdleCondition;
+    mutable std::condition_variable mWorkerIdleCondition;
     // Track worker thread Idle state for assertion purposes
     bool mWorkerThreadIdle;
+    // Command pool to allocate processor thread primary command buffers from
+    vk::CommandPool mCommandPool;
+    vk::PrimaryCommandBuffer mPrimaryCommandBuffer;
+    TaskProcessor mTaskProcessor;
+
+    AtomicSerialFactory mQueueSerialFactory;
+    std::mutex mCommandProcessorQueueSerialMutex;
+    Serial mCommandProcessorLastSubmittedSerial;
+    Serial mCommandProcessorCurrentQueueSerial;
+
+    mutable std::mutex mErrorMutex;
+    std::queue<vk::Error> mErrors;
 };
 
+}  // namespace vk
+
 }  // namespace rx
 
 #endif  // LIBANGLE_RENDERER_VULKAN_COMMAND_PROCESSOR_H_

src/libANGLE/renderer/vulkan/ContextVk.cpp

@@ -480,7 +480,6 @@ void CommandQueue::clearAllGarbage(RendererVk *renderer)
 }
 
 angle::Result CommandQueue::allocatePrimaryCommandBuffer(vk::Context *context,
-                                                         const vk::CommandPool &commandPool,
                                                          vk::PrimaryCommandBuffer *commandBufferOut)
 {
     return mPrimaryCommandPool.allocate(context, commandBufferOut);
@@ -523,6 +522,8 @@ bool CommandQueue::hasInFlightCommands() const
 
 angle::Result CommandQueue::finishToSerial(vk::Context *context, Serial serial, uint64_t timeout)
 {
+    ASSERT(!context->getRenderer()->getFeatures().asynchronousCommandProcessing.enabled);
+
     if (mInFlightCommands.empty())
     {
         return angle::Result::Continue;
@@ -607,6 +608,8 @@ angle::Result CommandQueue::submitFrame(vk::Context *context,
 
 vk::Shared<vk::Fence> CommandQueue::getLastSubmittedFence(const vk::Context *context) const
 {
+    ASSERT(!context->getRenderer()->getFeatures().enableCommandProcessingThread.enabled);
+
     vk::Shared<vk::Fence> fence;
     if (!mInFlightCommands.empty())
     {
@@ -958,7 +961,7 @@ angle::Result ContextVk::initialize()
 
 angle::Result ContextVk::startPrimaryCommandBuffer()
 {
-    ANGLE_TRY(mCommandQueue.allocatePrimaryCommandBuffer(this, mCommandPool, &mPrimaryCommands));
+    ANGLE_TRY(mCommandQueue.allocatePrimaryCommandBuffer(this, &mPrimaryCommands));
 
     VkCommandBufferBeginInfo beginInfo = {};
     beginInfo.sType                    = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
@@ -1407,6 +1410,8 @@ angle::Result ContextVk::handleDirtyGraphicsPipeline(const gl::Context *context,
     commandBuffer->bindGraphicsPipeline(mCurrentGraphicsPipeline->getPipeline());
     // Update the queue serial for the pipeline object.
     ASSERT(mCurrentGraphicsPipeline && mCurrentGraphicsPipeline->valid());
+    // TODO: https://issuetracker.google.com/issues/169788986: Need to change this so that we get
+    // the actual serial used when this work is submitted.
     mCurrentGraphicsPipeline->updateSerial(getCurrentQueueSerial());
     return angle::Result::Continue;
 }
@@ -1421,6 +1426,8 @@ angle::Result ContextVk::handleDirtyComputePipeline(const gl::Context *context,
     }
 
     commandBuffer->bindComputePipeline(mCurrentComputePipeline->get());
+    // TODO: https://issuetracker.google.com/issues/169788986: Need to change this so that we get
+    // the actual serial used when this work is submitted.
     mCurrentComputePipeline->updateSerial(getCurrentQueueSerial());
 
     return angle::Result::Continue;
@@ -1750,10 +1757,30 @@ void ContextVk::addOverlayUsedBuffersCount(vk::CommandBufferHelper *commandBuffe
     }
 }
 
+void ContextVk::commandProcessorSyncErrors()
+{
+    while (mRenderer->hasPendingError())
+    {
+        vk::Error error = mRenderer->getAndClearPendingError();
+        if (error.mErrorCode != VK_SUCCESS)
+        {
+            handleError(error.mErrorCode, error.mFile, error.mFunction, error.mLine);
+        }
+    }
+}
+
+void ContextVk::commandProcessorSyncErrorsAndQueueCommand(vk::CommandProcessorTask *command)
+{
+    commandProcessorSyncErrors();
+    mRenderer->queueCommand(this, command);
+}
+
 angle::Result ContextVk::submitFrame(const VkSubmitInfo &submitInfo,
                                      vk::ResourceUseList *resourceList,
                                      vk::PrimaryCommandBuffer &&commandBuffer)
 {
+    ASSERT(!getRenderer()->getFeatures().enableCommandProcessingThread.enabled);
+
     if (vk::CommandBufferHelper::kEnableCommandStreamDiagnostics)
     {
         dumpCommandStreamDiagnostics();
@@ -1932,6 +1959,8 @@ angle::Result ContextVk::synchronizeCpuGpuTime()
         double TeS = platform->monotonicallyIncreasingTime(platform);
 
         // Get the query results
+        // Note: This LastSubmittedQueueSerial may include more work then was submitted above if
+        // another thread had submitted work.
         ANGLE_TRY(finishToSerial(getLastSubmittedQueueSerial()));
 
         uint64_t gpuTimestampCycles = 0;
@@ -2086,13 +2115,22 @@ void ContextVk::flushGpuEvents(double nextSyncGpuTimestampS, double nextSyncCpuT
 
 void ContextVk::clearAllGarbage()
 {
-    ANGLE_TRACE_EVENT0("gpu.angle", "ContextVk::clearAllGarbage");
+    ANGLE_TRACE_EVENT0("gpu.angle", "ContextVk::finishAllWork");
     for (vk::GarbageObject &garbage : mCurrentGarbage)
     {
         garbage.destroy(mRenderer);
     }
     mCurrentGarbage.clear();
-    mCommandQueue.clearAllGarbage(mRenderer);
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        // Issue command to CommandProcessor to ensure all work is complete, which will return any
+        // garbage items as well.
+        mRenderer->finishAllWork(this);
+    }
+    else
+    {
+        mCommandQueue.clearAllGarbage(mRenderer);
+    }
 }
 
 void ContextVk::handleDeviceLost()
@@ -2100,7 +2138,14 @@ void ContextVk::handleDeviceLost()
     mOutsideRenderPassCommands->reset();
     mRenderPassCommands->reset();
 
-    mCommandQueue.handleDeviceLost(mRenderer);
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        mRenderer->handleDeviceLost();
+    }
+    else
+    {
+        mCommandQueue.handleDeviceLost(mRenderer);
+    }
     clearAllGarbage();
 
     mRenderer->notifyDeviceLost();
@@ -3283,6 +3328,10 @@ angle::Result ContextVk::onMakeCurrent(const gl::Context *context)
 angle::Result ContextVk::onUnMakeCurrent(const gl::Context *context)
 {
     ANGLE_TRY(flushImpl(nullptr));
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        mRenderer->waitForCommandProcessorIdle(this);
+    }
     mCurrentWindowSurface = nullptr;
     return angle::Result::Continue;
 }
@@ -4286,32 +4335,66 @@ angle::Result ContextVk::flushImpl(const vk::Semaphore *signalSemaphore)
     mDefaultUniformStorage.releaseInFlightBuffersToResourceUseList(this);
     mStagingBuffer.releaseInFlightBuffersToResourceUseList(this);
 
+    // TODO: https://issuetracker.google.com/issues/170329600 - Verify that
+    // waitForSwapchainImageIfNecessary makes sense both w/ & w/o threading. I believe they do, but
+    // want confirmation.
+    waitForSwapchainImageIfNecessary();
+
     if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
     {
-        // Worker thread must complete adding any commands that were just flushed above to the
-        //  primary command buffer before we can End the primary command buffer below.
-        mRenderer->waitForWorkerThreadIdle();
-    }
+        // Some tasks from ContextVk::submitFrame() that run before CommandQueue::submitFrame()
+        gl::RunningGraphWidget *renderPassCount =
+            mState.getOverlay()->getRunningGraphWidget(gl::WidgetId::VulkanRenderPassCount);
+        renderPassCount->add(mRenderPassCommands->getAndResetCounter());
+        renderPassCount->next();
 
-    ANGLE_VK_TRY(this, mPrimaryCommands.end());
+        if (vk::CommandBufferHelper::kEnableCommandStreamDiagnostics)
+        {
+            dumpCommandStreamDiagnostics();
+        }
 
-    waitForSwapchainImageIfNecessary();
+        // Send a flush command to worker thread that will:
+        // 1. Create submitInfo
+        // 2. Call submitFrame()
+        // 3. Allocate new primary command buffer
+        vk::CommandProcessorTask flushAndQueueSubmit;
+        flushAndQueueSubmit.initFlushAndQueueSubmit(
+            std::move(mWaitSemaphores), std::move(mWaitSemaphoreStageMasks), signalSemaphore,
+            mContextPriority, std::move(mCurrentGarbage), std::move(mResourceUseList));
 
-    VkSubmitInfo submitInfo = {};
-    InitializeSubmitInfo(&submitInfo, mPrimaryCommands, mWaitSemaphores, mWaitSemaphoreStageMasks,
-                         signalSemaphore);
+        commandProcessorSyncErrorsAndQueueCommand(&flushAndQueueSubmit);
 
-    ANGLE_TRY(submitFrame(submitInfo, &mResourceUseList, std::move(mPrimaryCommands)));
+        // Some tasks from ContextVk::submitFrame() that run after CommandQueue::submitFrame()
+        onRenderPassFinished();
+        mComputeDirtyBits |= mNewComputeCommandBufferDirtyBits;
 
-    ANGLE_TRY(startPrimaryCommandBuffer());
+        if (mGpuEventsEnabled)
+        {
+            ANGLE_TRY(checkCompletedGpuEvents());
+        }
+    }
+    else
+    {
+        ANGLE_VK_TRY(this, mPrimaryCommands.end());
+
+        VkSubmitInfo submitInfo = {};
+        InitializeSubmitInfo(&submitInfo, mPrimaryCommands, mWaitSemaphores,
+                             mWaitSemaphoreStageMasks, signalSemaphore);
+
+        ANGLE_TRY(submitFrame(submitInfo, &mResourceUseList, std::move(mPrimaryCommands)));
+
+        ANGLE_TRY(startPrimaryCommandBuffer());
+        mWaitSemaphores.clear();
+        mWaitSemaphoreStageMasks.clear();
+    }
 
     mPerfCounters.renderPasses                           = 0;
     mPerfCounters.writeDescriptorSets                    = 0;
     mPerfCounters.flushedOutsideRenderPassCommandBuffers = 0;
     mPerfCounters.resolveImageCommands                   = 0;
 
-    mWaitSemaphores.clear();
-    mWaitSemaphoreStageMasks.clear();
+    ASSERT(mWaitSemaphores.empty());
+    ASSERT(mWaitSemaphoreStageMasks.empty());
 
     mPerfCounters.primaryBuffers++;
 
@@ -4331,8 +4414,15 @@ angle::Result ContextVk::finishImpl()
 
     ANGLE_TRY(flushImpl(nullptr));
 
-    ANGLE_TRY(finishToSerial(getLastSubmittedQueueSerial()));
-    ASSERT(!mCommandQueue.hasInFlightCommands());
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        ANGLE_TRY(finishToSerial(getLastSubmittedQueueSerial()));
+    }
+    else
+    {
+        ANGLE_TRY(finishToSerial(getLastSubmittedQueueSerial()));
+        ASSERT(!mCommandQueue.hasInFlightCommands());
+    }
 
     clearAllGarbage();
 
@@ -4373,17 +4463,25 @@ bool ContextVk::isSerialInUse(Serial serial) const
 
 angle::Result ContextVk::checkCompletedCommands()
 {
+    ASSERT(!mRenderer->getFeatures().enableCommandProcessingThread.enabled);
+
     return mCommandQueue.checkCompletedCommands(this);
 }
 
 angle::Result ContextVk::finishToSerial(Serial serial)
 {
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        mRenderer->finishToSerial(this, serial);
+        return angle::Result::Continue;
+    }
     return mCommandQueue.finishToSerial(this, serial, mRenderer->getMaxFenceWaitTimeNs());
 }
 
 angle::Result ContextVk::getCompatibleRenderPass(const vk::RenderPassDesc &desc,
                                                  vk::RenderPass **renderPassOut)
 {
+    // Note: Each context has it's own RenderPassCache so no locking needed.
     return mRenderPassCache.getCompatibleRenderPass(this, desc, renderPassOut);
 }
 
@@ -4391,6 +4489,7 @@ angle::Result ContextVk::getRenderPassWithOps(const vk::RenderPassDesc &desc,
                                               const vk::AttachmentOpsArray &ops,
                                               vk::RenderPass **renderPassOut)
 {
+    // Note: Each context has it's own RenderPassCache so no locking needed.
     return mRenderPassCache.getRenderPassWithOps(this, desc, ops, renderPassOut);
 }
 
@@ -4400,12 +4499,13 @@ angle::Result ContextVk::ensureSubmitFenceInitialized()
     {
         return angle::Result::Continue;
     }
-
     return mRenderer->newSharedFence(this, &mSubmitFence);
 }
 
 angle::Result ContextVk::getNextSubmitFence(vk::Shared<vk::Fence> *sharedFenceOut)
 {
+    ASSERT(!getRenderer()->getFeatures().enableCommandProcessingThread.enabled);
+
     ANGLE_TRY(ensureSubmitFenceInitialized());
 
     ASSERT(!sharedFenceOut->isReferenced());
@@ -4415,6 +4515,10 @@ angle::Result ContextVk::getNextSubmitFence(vk::Shared<vk::Fence> *sharedFenceOu
 
 vk::Shared<vk::Fence> ContextVk::getLastSubmittedFence() const
 {
+    if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        return mRenderer->getLastSubmittedFence();
+    }
     return mCommandQueue.getLastSubmittedFence(this);
 }
 
@@ -4817,17 +4921,26 @@ angle::Result ContextVk::flushCommandsAndEndRenderPass()
 
     mRenderPassCommands->endRenderPass(this);
 
+    if (vk::CommandBufferHelper::kEnableCommandStreamDiagnostics)
+    {
+        mRenderPassCommands->addCommandDiagnostics(this);
+    }
+
+    vk::RenderPass *renderPass = nullptr;
+    ANGLE_TRY(mRenderPassCommands->getRenderPassWithOps(this, &renderPass));
     if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
     {
         mRenderPassCommands->markClosed();
-        vk::CommandProcessorTask task = {this, &mPrimaryCommands, mRenderPassCommands};
+        vk::CommandProcessorTask flushToPrimary;
+        flushToPrimary.initProcessCommands(this, mRenderPassCommands, renderPass);
         ANGLE_TRACE_EVENT0("gpu.angle", "ContextVk::flushInsideRenderPassCommands");
-        queueCommandsToWorker(task);
+        commandProcessorSyncErrorsAndQueueCommand(&flushToPrimary);
         getNextAvailableCommandBuffer(&mRenderPassCommands, true);
     }
     else
     {
-        ANGLE_TRY(mRenderPassCommands->flushToPrimary(this, &mPrimaryCommands));
+        ANGLE_TRY(mRenderPassCommands->flushToPrimary(this->getFeatures(), &mPrimaryCommands,
+                                                      renderPass));
     }
 
     mHasPrimaryCommands = true;
@@ -4958,17 +5071,26 @@ angle::Result ContextVk::flushOutsideRenderPassCommands()
 
     addOverlayUsedBuffersCount(mOutsideRenderPassCommands);
 
+    if (vk::CommandBufferHelper::kEnableCommandStreamDiagnostics)
+    {
+        mOutsideRenderPassCommands->addCommandDiagnostics(this);
+    }
+
+    vk::RenderPass *renderPass = nullptr;
+    ANGLE_TRY(mOutsideRenderPassCommands->getRenderPassWithOps(this, &renderPass));
     if (mRenderer->getFeatures().enableCommandProcessingThread.enabled)
     {
         mOutsideRenderPassCommands->markClosed();
-        vk::CommandProcessorTask task = {this, &mPrimaryCommands, mOutsideRenderPassCommands};
+        vk::CommandProcessorTask flushToPrimary;
+        flushToPrimary.initProcessCommands(this, mOutsideRenderPassCommands, renderPass);
         ANGLE_TRACE_EVENT0("gpu.angle", "ContextVk::flushOutsideRenderPassCommands");
-        queueCommandsToWorker(task);
+        commandProcessorSyncErrorsAndQueueCommand(&flushToPrimary);
         getNextAvailableCommandBuffer(&mOutsideRenderPassCommands, false);
     }
     else
     {
-        ANGLE_TRY(mOutsideRenderPassCommands->flushToPrimary(this, &mPrimaryCommands));
+        ANGLE_TRY(mOutsideRenderPassCommands->flushToPrimary(getFeatures(), &mPrimaryCommands,
+                                                             renderPass));
     }
     mHasPrimaryCommands = true;
     mPerfCounters.flushedOutsideRenderPassCommandBuffers++;

src/libANGLE/renderer/vulkan/ContextVk.h

@@ -47,7 +47,6 @@ class CommandQueue final : angle::NonCopyable
     bool hasInFlightCommands() const;
 
     angle::Result allocatePrimaryCommandBuffer(vk::Context *context,
-                                               const vk::CommandPool &commandPool,
                                                vk::PrimaryCommandBuffer *commandBufferOut);
     angle::Result releasePrimaryCommandBuffer(vk::Context *context,
                                               vk::PrimaryCommandBuffer &&commandBuffer);
@@ -653,11 +652,10 @@ class ContextVk : public ContextImpl, public vk::Context
     void updateOverlayOnPresent();
     void addOverlayUsedBuffersCount(vk::CommandBufferHelper *commandBuffer);
 
-    // Submit commands to worker thread for processing
-    ANGLE_INLINE void queueCommandsToWorker(const vk::CommandProcessorTask &commands)
-    {
-        mRenderer->queueCommands(commands);
-    }
+    // Sync any errors from the command processor
+    void commandProcessorSyncErrors();
+    // Sync any error from worker thread and queue up next command for processing
+    void commandProcessorSyncErrorsAndQueueCommand(vk::CommandProcessorTask *command);
     // When worker thread completes, it releases command buffers back to context queue
     void recycleCommandBuffer(vk::CommandBufferHelper *commandBuffer);
 
@@ -1085,6 +1083,7 @@ class ContextVk : public ContextImpl, public vk::Context
     // We use a single pool for recording commands. We also keep a free list for pool recycling.
     vk::CommandPool mCommandPool;
 
+    // TODO: This can be killed once threading is enabled https://issuetracker.google.com/153666475
     CommandQueue mCommandQueue;
     vk::GarbageList mCurrentGarbage;
 

src/libANGLE/renderer/vulkan/QueryVk.cpp

@@ -180,18 +180,30 @@ angle::Result QueryVk::getResult(const gl::Context *context, bool wait)
     // finite time.
     // Note regarding time-elapsed: end should have been called after begin, so flushing when end
     // has pending work should flush begin too.
-    if (mQueryHelper.hasPendingWork(contextVk))
+    // TODO: https://issuetracker.google.com/169788986 - can't guarantee hasPendingWork() works when
+    // using threaded worker
+    if (mQueryHelper.hasPendingWork(contextVk) ||
+        contextVk->getRenderer()->getFeatures().enableCommandProcessingThread.enabled)
     {
         ANGLE_TRY(contextVk->flushImpl(nullptr));
+        if (contextVk->getRenderer()->getFeatures().enableCommandProcessingThread.enabled)
+        {
+            // TODO: https://issuetracker.google.com/170312581 - For now just stalling here
+            contextVk->getRenderer()->waitForCommandProcessorIdle(contextVk);
+        }
 
         ASSERT(!mQueryHelperTimeElapsedBegin.hasPendingWork(contextVk));
         ASSERT(!mQueryHelper.hasPendingWork(contextVk));
     }
 
-    // If the command buffer this query is being written to is still in flight, its reset command
-    // may not have been performed by the GPU yet.  To avoid a race condition in this case, wait
-    // for the batch to finish first before querying (or return not-ready if not waiting).
-    ANGLE_TRY(contextVk->checkCompletedCommands());
+    if (!contextVk->getRenderer()->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        // If the command buffer this query is being written to is still in flight, its reset
+        // command may not have been performed by the GPU yet.  To avoid a race condition in this
+        // case, wait for the batch to finish first before querying (or return not-ready if not
+        // waiting).
+        ANGLE_TRY(contextVk->checkCompletedCommands());
+    }
     if (contextVk->isSerialInUse(mQueryHelper.getStoredQueueSerial()))
     {
         if (!wait)

src/libANGLE/renderer/vulkan/RendererVk.cpp

@@ -467,6 +467,7 @@ RendererVk::RendererVk()
       mPipelineCacheVkUpdateTimeout(kPipelineCacheVkUpdatePeriod),
       mPipelineCacheDirty(false),
       mPipelineCacheInitialized(false),
+      mCommandProcessor(this),
       mGlslangInitialized(false)
 {
     VkFormatProperties invalid = {0, 0, kInvalidFormatFeatureFlags};
@@ -536,6 +537,10 @@ void RendererVk::onDestroy()
         std::lock_guard<std::mutex> lock(mFenceRecyclerMutex);
         mFenceRecycler.destroy(mDevice);
     }
+    {
+        std::lock_guard<decltype(mNextSubmitFenceMutex)> lock(mNextSubmitFenceMutex);
+        mNextSubmitFence.reset(mDevice);
+    }
 
     mPipelineCache.destroy(mDevice);
     mSamplerCache.destroy(this);
@@ -580,7 +585,7 @@ void RendererVk::notifyDeviceLost()
 {
     {
         std::lock_guard<std::mutex> lock(mQueueSerialMutex);
-        mLastCompletedQueueSerial = mLastSubmittedQueueSerial;
+        mLastCompletedQueueSerial = getLastSubmittedQueueSerial();
     }
     mDeviceLost = true;
     mDisplay->notifyDeviceLost();
@@ -909,7 +914,8 @@ angle::Result RendererVk::initialize(DisplayVk *displayVk,
     if (getFeatures().enableCommandProcessingThread.enabled)
     {
         mCommandProcessorThread =
-            std::thread(&CommandProcessor::processCommandProcessorTasks, &mCommandProcessor);
+            std::thread(&vk::CommandProcessor::processTasks, &mCommandProcessor);
+        mCommandProcessor.waitForWorkComplete(nullptr);
     }
 
     return angle::Result::Continue;
@@ -1907,6 +1913,9 @@ void RendererVk::initFeatures(DisplayVk *displayVk, const ExtensionNameList &dev
     // Currently disabled by default: http://anglebug.com/4324
     ANGLE_FEATURE_CONDITION(&mFeatures, enableCommandProcessingThread, false);
 
+    // Currently disabled by default: http://anglebug.com/4324
+    ANGLE_FEATURE_CONDITION(&mFeatures, asynchronousCommandProcessing, false);
+
     ANGLE_FEATURE_CONDITION(&mFeatures, supportsYUVSamplerConversion,
                             mSamplerYcbcrConversionFeatures.samplerYcbcrConversion != VK_FALSE);
 
@@ -2183,6 +2192,17 @@ bool RendererVk::hasBufferFormatFeatureBits(VkFormat format,
     return hasFormatFeatureBits<&VkFormatProperties::bufferFeatures>(format, featureBits);
 }
 
+void RendererVk::outputVmaStatString()
+{
+    // Output the VMA stats string
+    // This JSON string can be passed to VmaDumpVis.py to generate a visualization of the
+    // allocations the VMA has performed.
+    char *statsString;
+    mAllocator.buildStatsString(&statsString, true);
+    INFO() << std::endl << statsString << std::endl;
+    mAllocator.freeStatsString(statsString);
+}
+
 angle::Result RendererVk::queueSubmit(vk::Context *context,
                                       egl::ContextPriority priority,
                                       const VkSubmitInfo &submitInfo,
@@ -2192,23 +2212,11 @@ angle::Result RendererVk::queueSubmit(vk::Context *context,
 {
     if (kOutputVmaStatsString)
     {
-        // Output the VMA stats string
-        // This JSON string can be passed to VmaDumpVis.py to generate a visualization of the
-        // allocations the VMA has performed.
-        char *statsString;
-        mAllocator.buildStatsString(&statsString, true);
-        INFO() << std::endl << statsString << std::endl;
-        mAllocator.freeStatsString(statsString);
+        outputVmaStatString();
     }
 
-    if (getFeatures().enableCommandProcessingThread.enabled)
-    {
-        // For initial threading phase 1 code make sure any outstanding command processing
-        //  is complete.
-        // TODO: b/153666475 For phase2 investigate if this is required as most submits will take
-        //  place through worker thread except for one-off submits below.
-        mCommandProcessor.waitForWorkComplete();
-    }
+    ASSERT(!getFeatures().enableCommandProcessingThread.enabled);
+
     {
         std::lock_guard<decltype(mQueueMutex)> lock(mQueueMutex);
         std::lock_guard<std::mutex> serialLock(mQueueSerialMutex);
@@ -2235,12 +2243,26 @@ angle::Result RendererVk::queueSubmitOneOff(vk::Context *context,
                                             const vk::Fence *fence,
                                             Serial *serialOut)
 {
-    VkSubmitInfo submitInfo       = {};
-    submitInfo.sType              = VK_STRUCTURE_TYPE_SUBMIT_INFO;
-    submitInfo.commandBufferCount = 1;
-    submitInfo.pCommandBuffers    = primary.ptr();
+    if (getFeatures().enableCommandProcessingThread.enabled)
+    {
+        vk::CommandProcessorTask oneOffQueueSubmit;
+        oneOffQueueSubmit.initOneOffQueueSubmit(primary.getHandle(), priority, fence);
+        queueCommand(context, &oneOffQueueSubmit);
+        waitForCommandProcessorIdle(context);
+        *serialOut = getLastSubmittedQueueSerial();
+
+        ANGLE_TRY(cleanupGarbage(false));
+    }
+    else
+    {
+
+        VkSubmitInfo submitInfo       = {};
+        submitInfo.sType              = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+        submitInfo.commandBufferCount = 1;
+        submitInfo.pCommandBuffers    = primary.ptr();
 
-    ANGLE_TRY(queueSubmit(context, priority, submitInfo, nullptr, fence, serialOut));
+        ANGLE_TRY(queueSubmit(context, priority, submitInfo, nullptr, fence, serialOut));
+    }
 
     mPendingOneOffCommands.push_back({*serialOut, std::move(primary)});
 
@@ -2251,8 +2273,8 @@ angle::Result RendererVk::queueWaitIdle(vk::Context *context, egl::ContextPriori
 {
     if (getFeatures().enableCommandProcessingThread.enabled)
     {
-        // First make sure command processor is complete when waiting for queue idle.
-        mCommandProcessor.waitForWorkComplete();
+        // Wait for all pending commands to get sent before issuing vkQueueWaitIdle
+        waitForCommandProcessorIdle(context);
     }
     {
         std::lock_guard<decltype(mQueueMutex)> lock(mQueueMutex);
@@ -2268,8 +2290,8 @@ angle::Result RendererVk::deviceWaitIdle(vk::Context *context)
 {
     if (getFeatures().enableCommandProcessingThread.enabled)
     {
-        // First make sure command processor is complete when waiting for device idle.
-        mCommandProcessor.waitForWorkComplete();
+        // Wait for all pending commands to get sent before issuing vkQueueWaitIdle
+        waitForCommandProcessorIdle(context);
     }
     {
         std::lock_guard<decltype(mQueueMutex)> lock(mQueueMutex);
@@ -2286,12 +2308,7 @@ VkResult RendererVk::queuePresent(egl::ContextPriority priority,
 {
     ANGLE_TRACE_EVENT0("gpu.angle", "RendererVk::queuePresent");
 
-    if (getFeatures().enableCommandProcessingThread.enabled)
-    {
-        // First make sure command processor is complete before queue present as
-        //  present may have dependencies on that thread.
-        mCommandProcessor.waitForWorkComplete();
-    }
+    ASSERT(!getFeatures().enableCommandProcessingThread.enabled);
 
     std::lock_guard<decltype(mQueueMutex)> lock(mQueueMutex);
 
@@ -2329,6 +2346,30 @@ angle::Result RendererVk::newSharedFence(vk::Context *context,
     return angle::Result::Continue;
 }
 
+// Return a shared fence to be used for the next submit
+// Fence may be shared with a Sync object.
+// reset indicates that nextSubmitFence should be reset before returning. This ensures that the next
+// request for a submit fence gets a fresh fence.
+// TODO: https://issuetracker.google.com/issues/170312581 - move to CommandProcessor as part of
+// fence ownership follow-up task.
+angle::Result RendererVk::getNextSubmitFence(vk::Shared<vk::Fence> *sharedFenceOut, bool reset)
+{
+    std::lock_guard<decltype(mNextSubmitFenceMutex)> lock(mNextSubmitFenceMutex);
+    if (!mNextSubmitFence.isReferenced())
+    {
+        ANGLE_TRY(newSharedFence(&mCommandProcessor, &mNextSubmitFence));
+    }
+
+    ASSERT(!sharedFenceOut->isReferenced());
+    sharedFenceOut->copy(getDevice(), mNextSubmitFence);
+
+    if (reset)
+    {
+        resetSharedFence(&mNextSubmitFence);
+    }
+    return angle::Result::Continue;
+}
+
 template <VkFormatFeatureFlags VkFormatProperties::*features>
 VkFormatFeatureFlags RendererVk::getFormatFeatureBits(VkFormat format,
                                                       const VkFormatFeatureFlags featureBits) const

src/libANGLE/renderer/vulkan/RendererVk.h

@@ -168,6 +168,7 @@ class RendererVk : angle::NonCopyable
         return mPriorities[priority];
     }
 
+    // Queue submit that originates from the main thread
     angle::Result queueSubmit(vk::Context *context,
                               egl::ContextPriority priority,
                               const VkSubmitInfo &submitInfo,
@@ -197,6 +198,8 @@ class RendererVk : angle::NonCopyable
         sharedFenceIn->resetAndRecycle(&mFenceRecycler);
     }
 
+    angle::Result getNextSubmitFence(vk::Shared<vk::Fence> *sharedFenceOut, bool reset);
+
     template <typename... ArgsT>
     void collectGarbageAndReinit(vk::SharedResourceUse *use, ArgsT... garbageIn)
     {
@@ -224,6 +227,12 @@ class RendererVk : angle::NonCopyable
         }
     }
 
+    vk::Shared<vk::Fence> getLastSubmittedFence() const
+    {
+        return mCommandProcessor.getLastSubmittedFence();
+    }
+    void handleDeviceLost() { mCommandProcessor.handleDeviceLost(); }
+
     static constexpr size_t kMaxExtensionNames = 200;
     using ExtensionNameList = angle::FixedVector<const char *, kMaxExtensionNames>;
 
@@ -241,11 +250,19 @@ class RendererVk : angle::NonCopyable
 
     ANGLE_INLINE Serial getCurrentQueueSerial()
     {
+        if (getFeatures().enableCommandProcessingThread.enabled)
+        {
+            return mCommandProcessor.getCurrentQueueSerial();
+        }
         std::lock_guard<std::mutex> lock(mQueueSerialMutex);
         return mCurrentQueueSerial;
     }
     ANGLE_INLINE Serial getLastSubmittedQueueSerial()
     {
+        if (getFeatures().enableCommandProcessingThread.enabled)
+        {
+            return mCommandProcessor.getLastSubmittedSerial();
+        }
         std::lock_guard<std::mutex> lock(mQueueSerialMutex);
         return mLastSubmittedQueueSerial;
     }
@@ -264,11 +281,24 @@ class RendererVk : angle::NonCopyable
     vk::ActiveHandleCounter &getActiveHandleCounts() { return mActiveHandleCounts; }
 
     // Queue commands to worker thread for processing
-    void queueCommands(const vk::CommandProcessorTask &commands)
+    void queueCommand(vk::Context *context, vk::CommandProcessorTask *command)
     {
-        mCommandProcessor.queueCommands(commands);
+        mCommandProcessor.queueCommand(context, command);
+    }
+    bool hasPendingError() const { return mCommandProcessor.hasPendingError(); }
+    vk::Error getAndClearPendingError() { return mCommandProcessor.getAndClearPendingError(); }
+    void waitForCommandProcessorIdle(vk::Context *context)
+    {
+        mCommandProcessor.waitForWorkComplete(context);
     }
-    void waitForWorkerThreadIdle() { mCommandProcessor.waitForWorkComplete(); }
+
+    void finishToSerial(vk::Context *context, Serial serial)
+    {
+        mCommandProcessor.finishToSerial(context, serial);
+    }
+
+    void finishAllWork(vk::Context *context) { mCommandProcessor.finishAllWork(context); }
+    VkQueue getVkQueue(egl::ContextPriority priority) const { return mQueues[priority]; }
 
     bool getEnableValidationLayers() const { return mEnableValidationLayers; }
 
@@ -276,6 +306,8 @@ class RendererVk : angle::NonCopyable
 
     void setGlobalDebugAnnotator();
 
+    void outputVmaStatString();
+
   private:
     angle::Result initializeDevice(DisplayVk *displayVk, uint32_t queueFamilyIndex);
     void ensureCapsInitialized() const;
@@ -390,9 +422,13 @@ class RendererVk : angle::NonCopyable
     };
     std::deque<PendingOneOffCommands> mPendingOneOffCommands;
 
-    // Worker Thread
-    CommandProcessor mCommandProcessor;
+    // Command Processor Thread
+    vk::CommandProcessor mCommandProcessor;
     std::thread mCommandProcessorThread;
+    // mNextSubmitFence is the fence that's going to be signaled at the next submission.  This is
+    // used to support SyncVk objects, which may outlive the context (as EGLSync objects).
+    vk::Shared<vk::Fence> mNextSubmitFence;
+    std::mutex mNextSubmitFenceMutex;
 
     // track whether we initialized (or released) glslang
     bool mGlslangInitialized;

src/libANGLE/renderer/vulkan/ResourceVk.cpp

@@ -102,11 +102,22 @@ ResourceUseList::ResourceUseList()
     mResourceUses.reserve(kDefaultResourceUseCount);
 }
 
+ResourceUseList::ResourceUseList(ResourceUseList &&other)
+{
+    *this = std::move(other);
+}
+
 ResourceUseList::~ResourceUseList()
 {
     ASSERT(mResourceUses.empty());
 }
 
+ResourceUseList &ResourceUseList::operator=(ResourceUseList &&rhs)
+{
+    std::swap(mResourceUses, rhs.mResourceUses);
+    return *this;
+}
+
 void ResourceUseList::releaseResourceUses()
 {
     for (SharedResourceUse &use : mResourceUses)

src/libANGLE/renderer/vulkan/ResourceVk.h

@@ -136,7 +136,9 @@ class ResourceUseList final : angle::NonCopyable
 {
   public:
     ResourceUseList();
+    ResourceUseList(ResourceUseList &&other);
     virtual ~ResourceUseList();
+    ResourceUseList &operator=(ResourceUseList &&rhs);
 
     void add(const SharedResourceUse &resourceUse);
 

src/libANGLE/renderer/vulkan/SurfaceVk.cpp

@@ -1186,6 +1186,7 @@ angle::Result WindowSurfaceVk::present(ContextVk *contextVk,
                                        bool *presentOutOfDate)
 {
     ANGLE_TRACE_EVENT0("gpu.angle", "WindowSurfaceVk::present");
+    RendererVk *renderer = contextVk->getRenderer();
 
     // Throttle the submissions to avoid getting too far ahead of the GPU.
     SwapHistory &swap = mSwapHistory[mCurrentSwapHistoryIndex];
@@ -1194,7 +1195,7 @@ angle::Result WindowSurfaceVk::present(ContextVk *contextVk,
         if (swap.sharedFence.isReferenced())
         {
             ANGLE_TRY(swap.waitFence(contextVk));
-            swap.destroy(contextVk->getRenderer());
+            swap.destroy(renderer);
         }
     }
 
@@ -1316,6 +1317,8 @@ angle::Result WindowSurfaceVk::present(ContextVk *contextVk,
     }
 
     // Update the swap history for this presentation
+    // TODO: https://issuetracker.google.com/issues/170312581 - this will force us to flush worker
+    // queue to get the fence.
     swap.sharedFence = contextVk->getLastSubmittedFence();
     ASSERT(!mAcquireImageSemaphore.valid());
 
@@ -1323,13 +1326,47 @@ angle::Result WindowSurfaceVk::present(ContextVk *contextVk,
     mCurrentSwapHistoryIndex =
         mCurrentSwapHistoryIndex == mSwapHistory.size() ? 0 : mCurrentSwapHistoryIndex;
 
-    VkResult result = contextVk->getRenderer()->queuePresent(contextVk->getPriority(), presentInfo);
+    VkResult result;
+    if (renderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        vk::CommandProcessorTask present;
+        present.initPresent(contextVk->getPriority(), presentInfo);
+
+        // Make sure everything has been submitted (and errors handled)
+        renderer->waitForCommandProcessorIdle(contextVk);
+
+        // Submit queuePresent all by itself (ignoring interference from other threads for now)
+        renderer->queueCommand(contextVk, &present);
+        // TODO: https://issuetracker.google.com/issues/170329600 - Just stalling here for now, but
+        // really want to let main thread continue
+        // need to figure out how to handle work below off-thread and sync to main
+        // Also, need to fix lifetime of presentInfo data when main thread continues.
+        // There is a bunch of work happening after present to deal with swapchain recreation.
+        // Will that require moving a large chunk of swapImpl to the CommandProcessor?
+        // That will likely require serializing access to the WindowSurfaceVk object in order
+        // to have current content.
+        result = VK_SUCCESS;
+
+        // wait for the queuePresent to be submitted and intentionally set the context to nullptr so
+        // that we can catch any error. Note this doesn't prevent another context from grabbing the
+        // error. Will be fixed properly in a follow-up as part of present work.
+        renderer->waitForCommandProcessorIdle(nullptr);
+        if (renderer->hasPendingError())
+        {
+            vk::Error error = renderer->getAndClearPendingError();
+            result          = error.mErrorCode;
+        }
+    }
+    else
+    {
+        result = renderer->queuePresent(contextVk->getPriority(), presentInfo);
+    }
 
     // If OUT_OF_DATE is returned, it's ok, we just need to recreate the swapchain before
     // continuing.
     // If VK_SUBOPTIMAL_KHR is returned it's because the device orientation changed and we should
     // recreate the swapchain with a new window orientation.
-    if (contextVk->getFeatures().enablePreRotateSurfaces.enabled)
+    if (renderer->getFeatures().enablePreRotateSurfaces.enabled)
     {
         // Also check for VK_SUBOPTIMAL_KHR.
         *presentOutOfDate = ((result == VK_ERROR_OUT_OF_DATE_KHR) || (result == VK_SUBOPTIMAL_KHR));

src/libANGLE/renderer/vulkan/SyncVk.cpp

@@ -32,6 +32,12 @@ SyncHelper::~SyncHelper() {}
 void SyncHelper::releaseToRenderer(RendererVk *renderer)
 {
     renderer->collectGarbageAndReinit(&mUse, &mEvent);
+    // TODO: https://issuetracker.google.com/170312581 - Currently just stalling on worker thread
+    // here to try and avoid race condition. If this works, need some alternate solution
+    if (renderer->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        renderer->waitForCommandProcessorIdle(nullptr);
+    }
     mFence.reset(renderer->getDevice());
 }
 
@@ -48,7 +54,17 @@ angle::Result SyncHelper::initialize(ContextVk *contextVk)
 
     DeviceScoped<Event> event(device);
     ANGLE_VK_TRY(contextVk, event.get().init(device, eventCreateInfo));
-    ANGLE_TRY(contextVk->getNextSubmitFence(&mFence));
+    // TODO: https://issuetracker.google.com/170312581 - For now wait for worker thread to finish
+    // then get next fence from renderer
+    if (contextVk->getRenderer()->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        contextVk->getRenderer()->waitForCommandProcessorIdle(contextVk);
+        ANGLE_TRY(contextVk->getRenderer()->getNextSubmitFence(&mFence, false));
+    }
+    else
+    {
+        ANGLE_TRY(contextVk->getNextSubmitFence(&mFence));
+    }
 
     mEvent = event.release();
 
@@ -90,9 +106,17 @@ angle::Result SyncHelper::clientWait(Context *context,
         ANGLE_TRY(contextVk->flushImpl(nullptr));
     }
 
+    // If we are using worker need to wait for the commands to be issued before waiting on the
+    // fence.
+    if (contextVk->getRenderer()->getFeatures().enableCommandProcessingThread.enabled)
+    {
+        contextVk->getRenderer()->waitForCommandProcessorIdle(contextVk);
+    }
+
     // Wait on the fence that's expected to be signaled on the first vkQueueSubmit after
     // `initialize` was called. The first fence is the fence created to signal this sync.
     ASSERT(mFence.get().valid());
+    // TODO: https://issuetracker.google.com/170312581 - Wait could be command to worker
     VkResult status = mFence.get().wait(renderer->getDevice(), timeout);
 
     // Check for errors, but don't consider timeout as such.
@@ -189,11 +213,24 @@ angle::Result SyncHelperNativeFence::initializeWithFd(ContextVk *contextVk, int
 
         retain(&contextVk->getResourceUseList());
 
-        Serial serialOut;
-        VkSubmitInfo submitInfo = {};
-        submitInfo.sType        = VK_STRUCTURE_TYPE_SUBMIT_INFO;
-        ANGLE_TRY(renderer->queueSubmit(contextVk, contextVk->getPriority(), submitInfo, nullptr,
-                                        &fence.get(), &serialOut));
+        if (renderer->getFeatures().enableCommandProcessingThread.enabled)
+        {
+            CommandProcessorTask oneOffQueueSubmit;
+            oneOffQueueSubmit.initOneOffQueueSubmit(VK_NULL_HANDLE, contextVk->getPriority(),
+                                                    &fence.get());
+            renderer->queueCommand(contextVk, &oneOffQueueSubmit);
+            // TODO: https://issuetracker.google.com/170312581 - wait for now
+            renderer->waitForCommandProcessorIdle(contextVk);
+        }
+        else
+        {
+            Serial serialOut;
+            VkSubmitInfo submitInfo = {};
+            submitInfo.sType        = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+
+            ANGLE_TRY(renderer->queueSubmit(contextVk, contextVk->getPriority(), submitInfo,
+                                            nullptr, &fence.get(), &serialOut));
+        }
 
         VkFenceGetFdInfoKHR fenceGetFdInfo = {};
         fenceGetFdInfo.sType               = VK_STRUCTURE_TYPE_FENCE_GET_FD_INFO_KHR;
@@ -253,6 +290,14 @@ angle::Result SyncHelperNativeFence::clientWait(Context *context,
     {
         ANGLE_TRY(contextVk->flushImpl(nullptr));
     }
+
+    // If we are using worker need to wait for the commands to be issued before waiting on the
+    // fence.
+    if (contextVk->getRenderer()->getFeatures().asynchronousCommandProcessing.enabled)
+    {
+        contextVk->getRenderer()->waitForCommandProcessorIdle(contextVk);
+    }
+
     // Wait for mFenceWithFd to be signaled.
     VkResult status = mFenceWithFd.wait(renderer->getDevice(), timeout);
 

src/libANGLE/renderer/vulkan/UtilsVk.cpp

@@ -969,6 +969,7 @@ angle::Result UtilsVk::setupProgram(ContextVk *contextVk,
         vk::PipelineAndSerial *pipelineAndSerial;
         program->setShader(gl::ShaderType::Compute, fsCsShader);
         ANGLE_TRY(program->getComputePipeline(contextVk, pipelineLayout.get(), &pipelineAndSerial));
+        // TODO: https://issuetracker.google.com/issues/169788986: Update serial handling.
         pipelineAndSerial->updateSerial(serial);
         commandBuffer->bindComputePipeline(pipelineAndSerial->get());
     }

src/libANGLE/renderer/vulkan/vk_helpers.cpp

@@ -916,7 +916,8 @@ void CommandBufferHelper::restoreStencilContent()
     }
 }
 
-void CommandBufferHelper::executeBarriers(ContextVk *contextVk, PrimaryCommandBuffer *primary)
+void CommandBufferHelper::executeBarriers(const angle::FeaturesVk &features,
+                                          PrimaryCommandBuffer *primary)
 {
     // make a local copy for faster access
     PipelineStagesMask mask = mPipelineBarrierMask;
@@ -925,7 +926,7 @@ void CommandBufferHelper::executeBarriers(ContextVk *contextVk, PrimaryCommandBu
         return;
     }
 
-    if (contextVk->getFeatures().preferAggregateBarrierCalls.enabled)
+    if (features.preferAggregateBarrierCalls.enabled)
     {
         PipelineStagesMask::Iterator iter = mask.begin();
         PipelineBarrier &barrier          = mPipelineBarriers[*iter];
@@ -1152,24 +1153,31 @@ void CommandBufferHelper::endTransformFeedback()
     mValidTransformFeedbackBufferCount = 0;
 }
 
-angle::Result CommandBufferHelper::flushToPrimary(ContextVk *contextVk,
-                                                  PrimaryCommandBuffer *primary)
+angle::Result CommandBufferHelper::getRenderPassWithOps(ContextVk *contextVk,
+                                                        RenderPass **renderPass)
 {
-    ANGLE_TRACE_EVENT0("gpu.angle", "CommandBufferHelper::flushToPrimary");
-    ASSERT(!empty());
-    if (kEnableCommandStreamDiagnostics)
+    *renderPass = nullptr;
+    if (mIsRenderPassCommandBuffer)
     {
-        addCommandDiagnostics(contextVk);
+        ANGLE_TRY(contextVk->getRenderPassWithOps(mRenderPassDesc, mAttachmentOps, renderPass));
     }
+    return angle::Result::Continue;
+}
+
+angle::Result CommandBufferHelper::flushToPrimary(const angle::FeaturesVk &features,
+                                                  PrimaryCommandBuffer *primary,
+                                                  RenderPass *renderPass)
+{
+    ANGLE_TRACE_EVENT0("gpu.angle", "CommandBufferHelper::flushToPrimary");
+    ASSERT(!empty());
+
     // Commands that are added to primary before beginRenderPass command
-    executeBarriers(contextVk, primary);
+    executeBarriers(features, primary);
 
     if (mIsRenderPassCommandBuffer)
     {
         mCommandBuffer.executeQueuedResetQueryPoolCommands(primary->getHandle());
-        // Pull a RenderPass from the cache.
-        RenderPass *renderPass = nullptr;
-        ANGLE_TRY(contextVk->getRenderPassWithOps(mRenderPassDesc, mAttachmentOps, &renderPass));
+        ASSERT(renderPass != nullptr);
 
         VkRenderPassBeginInfo beginInfo    = {};
         beginInfo.sType                    = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;

src/libANGLE/renderer/vulkan/vk_helpers.h

@@ -962,9 +962,12 @@ class CommandBufferHelper : angle::NonCopyable
 
     CommandBuffer &getCommandBuffer() { return mCommandBuffer; }
 
-    angle::Result flushToPrimary(ContextVk *contextVk, PrimaryCommandBuffer *primary);
+    angle::Result getRenderPassWithOps(ContextVk *contextVk, RenderPass **renderPass);
+    angle::Result flushToPrimary(const angle::FeaturesVk &features,
+                                 PrimaryCommandBuffer *primary,
+                                 RenderPass *renderPass);
 
-    void executeBarriers(ContextVk *contextVk, PrimaryCommandBuffer *primary);
+    void executeBarriers(const angle::FeaturesVk &features, PrimaryCommandBuffer *primary);
 
     void setHasRenderPass(bool hasRenderPass) { mIsRenderPassCommandBuffer = hasRenderPass; }
 
@@ -1129,9 +1132,9 @@ class CommandBufferHelper : angle::NonCopyable
 
     bool isReadOnlyDepthMode() const { return mReadOnlyDepthStencilMode; }
 
-  private:
     void addCommandDiagnostics(ContextVk *contextVk);
 
+  private:
     bool onDepthStencilAccess(ResourceAccess access,
                               uint32_t *cmdCountInvalidated,
                               uint32_t *cmdCountDisabled);

src/libANGLE/renderer/vulkan/vk_utils.h

@@ -943,15 +943,15 @@ gl::LevelIndex GetLevelIndex(vk::LevelIndex levelVk, gl::LevelIndex baseLevel);
 
 }  // namespace rx
 
-#define ANGLE_VK_TRY(context, command)                                                 \
-    do                                                                                 \
-    {                                                                                  \
-        auto ANGLE_LOCAL_VAR = command;                                                \
-        if (ANGLE_UNLIKELY(ANGLE_LOCAL_VAR != VK_SUCCESS))                             \
-        {                                                                              \
-            context->handleError(ANGLE_LOCAL_VAR, __FILE__, ANGLE_FUNCTION, __LINE__); \
-            return angle::Result::Stop;                                                \
-        }                                                                              \
+#define ANGLE_VK_TRY(context, command)                                                   \
+    do                                                                                   \
+    {                                                                                    \
+        auto ANGLE_LOCAL_VAR = command;                                                  \
+        if (ANGLE_UNLIKELY(ANGLE_LOCAL_VAR != VK_SUCCESS))                               \
+        {                                                                                \
+            (context)->handleError(ANGLE_LOCAL_VAR, __FILE__, ANGLE_FUNCTION, __LINE__); \
+            return angle::Result::Stop;                                                  \
+        }                                                                                \
     } while (0)
 
 #define ANGLE_VK_CHECK(context, test, error) ANGLE_VK_TRY(context, test ? VK_SUCCESS : error)