TheRock/rocm-libraries/projects/hipfft/shared/work_queue.h

// Copyright (C) 2022 Advanced Micro Devices, Inc. All rights reserved.
//
// 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
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// THE SOFTWARE.

#pragma once

#include <condition_variable>
#include <mutex>
#include <queue>
template <typename _WorkItem>
struct WorkQueue
{
    void push(_WorkItem&& i)
    {
        std::unique_lock<std::mutex> lock(queueMutex);
        items.emplace(std::move(i));
        emptyWait.notify_all();
    }
    _WorkItem pop()
    {
        std::unique_lock<std::mutex> lock(queueMutex);
        while(items.empty())
            emptyWait.wait(lock);
        _WorkItem item(items.front());
        items.pop();
        return item;
    }

private:
    std::queue<_WorkItem>   items;
    std::mutex              queueMutex;
    std::condition_variable emptyWait;
};