thread_pool.hpp

/* Copyright (c) 2016-2017, ARM Limited and Contributors
 *
 * SPDX-License-Identifier: MIT
 *
 * 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,
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 */

#ifndef FRAMEWORK_THREAD_POOL_HPP
#define FRAMEWORK_THREAD_POOL_HPP

#include <condition_variable>
#include <functional>
#include <memory>
#include <mutex>
#include <queue>
#include <thread>

namespace MaliSDK
{

class ThreadPool
{
public:
        void setWorkerThreadCount(unsigned workerThreadCount);

        unsigned getWorkerThreadCount() const
        {
                return workerThreads.size();
        }

        void pushWorkToThread(unsigned threadIndex, std::function<void()> func);

        void waitIdle();

private:
        class Worker
        {
        public:
                Worker();
                ~Worker();

                void pushWork(std::function<void()> func);
                void waitIdle();

        private:
                std::thread workerThread;
                std::mutex lock;
                std::condition_variable cond;

                std::queue<std::function<void()>> workQueue;
                bool threadIsAlive = true;

                void threadEntry();
        };

        std::vector<std::unique_ptr<Worker>> workerThreads;
};
}

#endif