FutexImpl.h#

// Copyright (c) 2020-2024, NVIDIA CORPORATION. All rights reserved.
//
// NVIDIA CORPORATION and its licensors retain all intellectual property
// and proprietary rights in and to this software, related documentation
// and any modifications thereto. Any use, reproduction, disclosure or
// distribution of this software and related documentation without an express
// license agreement from NVIDIA CORPORATION is strictly prohibited.
//

#pragma once

#include "NativeFutex.h"
#include "LowLevelLock.h"
#include "../../cpp/Bit.h"
#include "../../detail/TSan.h"

#include <atomic>

#ifndef DOXYGEN_BUILD
#    if CARB_PLATFORM_WINDOWS
// Windows WaitOnAddress() supports 1, 2, 4 or 8 bytes, so it doesn't need to use ParkingLot. For testing ParkingLot
// or for specific modules this can be enabled though.
#        ifndef CARB_USE_PARKINGLOT
#            define CARB_USE_PARKINGLOT 0
#        endif
#    elif CARB_PLATFORM_LINUX
#        define CARB_USE_PARKINGLOT 1 // Linux and macOS only support 4 byte futex so they must use the ParkingLot
#    else
CARB_UNSUPPORTED_PLATFORM()
#    endif
#endif

#if CARB_USE_PARKINGLOT
#    include "ParkingLot.h"
#endif

namespace carb
{
namespace thread
{
namespace detail
{

// Futex types that must use the ParkingLot
#if CARB_USE_PARKINGLOT
template <class T, size_t S = sizeof(T)>
using Futex = ParkingLotFutex<T, S>;
#elif CARB_PLATFORM_WINDOWS
// If Windows is not using the ParkingLot it can use the Windows-specific futex
template <class T, size_t S = sizeof(T)>
using Futex = WindowsFutex<T, S>;
#else
CARB_UNSUPPORTED_PLATFORM()
#endif

} // namespace detail
} // namespace thread
} // namespace carb