ceph/src/boost/boost/atomic/detail/fence_ops_gcc_sync.hpp

   1 /*
   2  * Distributed under the Boost Software License, Version 1.0.
   3  * (See accompanying file LICENSE_1_0.txt or copy at
   4  * http://www.boost.org/LICENSE_1_0.txt)
   5  *
   6  * Copyright (c) 2020 Andrey Semashev
   7  */
   8 /*!
   9  * \file   atomic/detail/fence_ops_gcc_sync.hpp
  10  *
  11  * This header contains implementation of the \c fence_operations struct.
  12  */
  13
  14 #ifndef BOOST_ATOMIC_DETAIL_FENCE_OPS_GCC_SYNC_HPP_INCLUDED_
  15 #define BOOST_ATOMIC_DETAIL_FENCE_OPS_GCC_SYNC_HPP_INCLUDED_
  16
  17 #include <boost/memory_order.hpp>
  18 #include <boost/atomic/detail/config.hpp>
  19 #include <boost/atomic/detail/header.hpp>
  20
  21 #ifdef BOOST_HAS_PRAGMA_ONCE
  22 #pragma once
  23 #endif
  24
  25 namespace boost {
  26 namespace atomics {
  27 namespace detail {
  28
  29 //! Fence operations based on gcc __sync* intrinsics
  30 struct fence_operations_gcc_sync
  31 {
  32     static BOOST_FORCEINLINE void thread_fence(memory_order order) BOOST_NOEXCEPT
  33     {
  34         if (order != memory_order_relaxed)
  35             __sync_synchronize();
  36     }
  37
  38     static BOOST_FORCEINLINE void signal_fence(memory_order order) BOOST_NOEXCEPT
  39     {
  40         if (order != memory_order_relaxed)
  41             __asm__ __volatile__ ("" ::: "memory");
  42     }
  43 };
  44
  45 typedef fence_operations_gcc_sync fence_operations;
  46
  47 } // namespace detail
  48 } // namespace atomics
  49 } // namespace boost
  50
  51 #include <boost/atomic/detail/footer.hpp>
  52
  53 #endif // BOOST_ATOMIC_DETAIL_FENCE_OPS_GCC_SYNC_HPP_INCLUDED_