/*
 * Copyright (c) 2017 - 2018, Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <atomic>
#include <iostream>
#include <queue>
#include <stdio.h>
#include "runtime/helpers/aligned_memory.h"
#include "drm_buffer_object.h"
#include "drm_command_stream.h"
#include "drm_gem_close_worker.h"
#include "drm_memory_manager.h"

namespace OCLRT {

DrmGemCloseWorker::DrmGemCloseWorker(DrmMemoryManager &memoryManager) : active(true), thread(nullptr), workCount(0), memoryManager(memoryManager),
                                                                        workerDone(false) {
    thread = new std::thread(&DrmGemCloseWorker::worker, this);
}

void DrmGemCloseWorker::closeThread() {
    if (thread) {
        while (!workerDone.load()) {
            condition.notify_all();
        }

        thread->join();
        delete thread;
        thread = nullptr;
    }
}

DrmGemCloseWorker::~DrmGemCloseWorker() {
    active = false;
    closeThread();
}

void DrmGemCloseWorker::push(BufferObject *bo) {
    std::unique_lock<std::mutex> lock(closeWorkerMutex);
    workCount++;
    queue.push(bo);
    lock.unlock();
    condition.notify_one();
}

void DrmGemCloseWorker::close(bool blocking) {
    active = false;
    condition.notify_all();
    if (blocking) {
        closeThread();
    }
}

bool DrmGemCloseWorker::isEmpty() {
    return workCount.load() == 0;
}

inline void DrmGemCloseWorker::close(BufferObject *bo) {
    bo->wait(-1);
    memoryManager.unreference(bo);
    workCount--;
}

void DrmGemCloseWorker::worker() {
    BufferObject *workItem = nullptr;
    std::queue<BufferObject *> localQueue;
    std::unique_lock<std::mutex> lock(closeWorkerMutex);
    lock.unlock();

    while (active) {
        lock.lock();
        workItem = nullptr;

        while (queue.empty() && active) {
            condition.wait(lock);
        }

        if (!queue.empty()) {
            localQueue.swap(queue);
        }

        lock.unlock();
        while (!localQueue.empty()) {
            workItem = localQueue.front();
            localQueue.pop();
            close(workItem);
        }
    }

    lock.lock();
    while (!queue.empty()) {
        workItem = queue.front();
        queue.pop();
        close(workItem);
    }

    lock.unlock();
    workerDone.store(true);
}
}