178 lines
3.2 KiB
Plaintext
178 lines
3.2 KiB
Plaintext
|
#ifndef BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
|
||
|
|
#define BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
|
||
|
|
|
||
|
|
// MS compatible compilers support #pragma once
|
||
|
|
|
||
|
|
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
|
||
|
|
# pragma once
|
||
|
|
#endif
|
||
|
|
|
||
|
|
//
|
||
|
|
// yield_k.hpp
|
||
|
|
//
|
||
|
|
// Copyright (c) 2008 Peter Dimov
|
||
|
|
// Copyright (c) Microsoft Corporation 2014
|
||
|
|
//
|
||
|
|
// void yield( unsigned k );
|
||
|
|
//
|
||
|
|
// Typical use:
|
||
|
|
//
|
||
|
|
// for( unsigned k = 0; !try_lock(); ++k ) yield( k );
|
||
|
|
//
|
||
|
|
// 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
|
||
|
|
//
|
||
|
|
|
||
|
|
#include <boost/config.hpp>
|
||
|
|
#include <boost/predef.h>
|
||
|
|
|
||
|
|
#if BOOST_PLAT_WINDOWS_RUNTIME
|
||
|
|
#include <thread>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
// BOOST_SMT_PAUSE
|
||
|
|
|
||
|
|
#if defined(_MSC_VER) && _MSC_VER >= 1310 && ( defined(_M_IX86) || defined(_M_X64) )
|
||
|
|
|
||
|
|
extern "C" void _mm_pause();
|
||
|
|
|
||
|
|
#define BOOST_SMT_PAUSE _mm_pause();
|
||
|
|
|
||
|
|
#elif defined(__GNUC__) && ( defined(__i386__) || defined(__x86_64__) )
|
||
|
|
|
||
|
|
#define BOOST_SMT_PAUSE __asm__ __volatile__( "rep; nop" : : : "memory" );
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|
||
|
|
//
|
||
|
|
|
||
|
|
#if defined( WIN32 ) || defined( _WIN32 ) || defined( __WIN32__ ) || defined( __CYGWIN__ )
|
||
|
|
|
||
|
|
#if defined( BOOST_USE_WINDOWS_H )
|
||
|
|
# include <windows.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
namespace boost
|
||
|
|
{
|
||
|
|
|
||
|
|
namespace detail
|
||
|
|
{
|
||
|
|
|
||
|
|
#if !defined( BOOST_USE_WINDOWS_H ) && !BOOST_PLAT_WINDOWS_RUNTIME
|
||
|
|
#if !BOOST_COMP_CLANG || !defined __MINGW32__
|
||
|
|
extern "C" void __stdcall Sleep( unsigned long ms );
|
||
|
|
#else
|
||
|
|
#include <_mingw.h>
|
||
|
|
#if !defined __MINGW64_VERSION_MAJOR
|
||
|
|
extern "C" void __stdcall Sleep( unsigned long ms );
|
||
|
|
#else
|
||
|
|
extern "C" __declspec(dllimport) void __stdcall Sleep( unsigned long ms );
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
|
||
|
|
inline void yield( unsigned k )
|
||
|
|
{
|
||
|
|
if( k < 4 )
|
||
|
|
{
|
||
|
|
}
|
||
|
|
#if defined( BOOST_SMT_PAUSE )
|
||
|
|
else if( k < 16 )
|
||
|
|
{
|
||
|
|
BOOST_SMT_PAUSE
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
#if !BOOST_PLAT_WINDOWS_RUNTIME
|
||
|
|
else if( k < 32 )
|
||
|
|
{
|
||
|
|
Sleep( 0 );
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
Sleep( 1 );
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Sleep isn't supported on the Windows Runtime.
|
||
|
|
std::this_thread::yield();
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#elif defined( BOOST_HAS_PTHREADS )
|
||
|
|
|
||
|
|
#ifndef _AIX
|
||
|
|
#include <sched.h>
|
||
|
|
#else
|
||
|
|
// AIX's sched.h defines ::var which sometimes conflicts with Lambda's var
|
||
|
|
extern "C" int sched_yield(void);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include <time.h>
|
||
|
|
|
||
|
|
namespace boost
|
||
|
|
{
|
||
|
|
|
||
|
|
namespace detail
|
||
|
|
{
|
||
|
|
|
||
|
|
inline void yield( unsigned k )
|
||
|
|
{
|
||
|
|
if( k < 4 )
|
||
|
|
{
|
||
|
|
}
|
||
|
|
#if defined( BOOST_SMT_PAUSE )
|
||
|
|
else if( k < 16 )
|
||
|
|
{
|
||
|
|
BOOST_SMT_PAUSE
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
else if( k < 32 || k & 1 )
|
||
|
|
{
|
||
|
|
sched_yield();
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// g++ -Wextra warns on {} or {0}
|
||
|
|
struct timespec rqtp = { 0, 0 };
|
||
|
|
|
||
|
|
// POSIX says that timespec has tv_sec and tv_nsec
|
||
|
|
// But it doesn't guarantee order or placement
|
||
|
|
|
||
|
|
rqtp.tv_sec = 0;
|
||
|
|
rqtp.tv_nsec = 1000;
|
||
|
|
|
||
|
|
nanosleep( &rqtp, 0 );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#else
|
||
|
|
|
||
|
|
namespace boost
|
||
|
|
{
|
||
|
|
|
||
|
|
namespace detail
|
||
|
|
{
|
||
|
|
|
||
|
|
inline void yield( unsigned )
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif // #ifndef BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
|