76 lines
2.3 KiB
C++
76 lines
2.3 KiB
C++
/*
|
|
* Distributed under the Boost Software License, Version 1.0.
|
|
* (See accompanying file LICENSE_1_0.txt or copy at
|
|
* http://www.boost.org/LICENSE_1_0.txt)
|
|
*
|
|
* Copyright (c) 2020 Andrey Semashev
|
|
*/
|
|
/*!
|
|
* \file atomic/detail/wait_ops_dragonfly_umtx.hpp
|
|
*
|
|
* This header contains implementation of the waiting/notifying atomic operations based on DragonFly BSD umtx.
|
|
* https://man.dragonflybsd.org/?command=umtx§ion=2
|
|
*/
|
|
|
|
#ifndef BOOST_ATOMIC_DETAIL_WAIT_OPS_DRAGONFLY_UMTX_HPP_INCLUDED_
|
|
#define BOOST_ATOMIC_DETAIL_WAIT_OPS_DRAGONFLY_UMTX_HPP_INCLUDED_
|
|
|
|
#include <unistd.h>
|
|
#include <boost/memory_order.hpp>
|
|
#include <boost/atomic/detail/config.hpp>
|
|
#include <boost/atomic/detail/wait_operations_fwd.hpp>
|
|
#include <boost/atomic/detail/header.hpp>
|
|
|
|
#ifdef BOOST_HAS_PRAGMA_ONCE
|
|
#pragma once
|
|
#endif
|
|
|
|
namespace boost {
|
|
namespace atomics {
|
|
namespace detail {
|
|
|
|
template< typename Base, bool Interprocess >
|
|
struct wait_operations< Base, sizeof(int), true, Interprocess > :
|
|
public Base
|
|
{
|
|
typedef Base base_type;
|
|
typedef typename base_type::storage_type storage_type;
|
|
|
|
static BOOST_CONSTEXPR_OR_CONST bool always_has_native_wait_notify = true;
|
|
|
|
static BOOST_FORCEINLINE bool has_native_wait_notify(storage_type const volatile&) BOOST_NOEXCEPT
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static BOOST_FORCEINLINE storage_type wait(storage_type const volatile& storage, storage_type old_val, memory_order order) BOOST_NOEXCEPT
|
|
{
|
|
storage_type new_val = base_type::load(storage, order);
|
|
while (new_val == old_val)
|
|
{
|
|
::umtx_sleep(reinterpret_cast< int* >(const_cast< storage_type* >(&storage)), static_cast< int >(old_val), 0);
|
|
new_val = base_type::load(storage, order);
|
|
}
|
|
|
|
return new_val;
|
|
}
|
|
|
|
static BOOST_FORCEINLINE void notify_one(storage_type volatile& storage) BOOST_NOEXCEPT
|
|
{
|
|
::umtx_wakeup(reinterpret_cast< int* >(const_cast< storage_type* >(&storage)), 1);
|
|
}
|
|
|
|
static BOOST_FORCEINLINE void notify_all(storage_type volatile& storage) BOOST_NOEXCEPT
|
|
{
|
|
::umtx_wakeup(reinterpret_cast< int* >(const_cast< storage_type* >(&storage)), 0);
|
|
}
|
|
};
|
|
|
|
} // namespace detail
|
|
} // namespace atomics
|
|
} // namespace boost
|
|
|
|
#include <boost/atomic/detail/footer.hpp>
|
|
|
|
#endif // BOOST_ATOMIC_DETAIL_WAIT_OPS_DRAGONFLY_UMTX_HPP_INCLUDED_
|