From: pdimov_at_[hidden]
Date: 2008-03-27 18:20:12
Author: pdimov
Date: 2008-03-27 18:20:11 EDT (Thu, 27 Mar 2008)
New Revision: 43888
URL: http://svn.boost.org/trac/boost/changeset/43888
Log:
detail::yield(k) added.
Added:
trunk/boost/detail/yield_k.hpp (contents, props changed)
trunk/libs/smart_ptr/test/yield_k_test.cpp (contents, props changed)
Text files modified:
trunk/libs/smart_ptr/test/Jamfile.v2 | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
Added: trunk/boost/detail/yield_k.hpp
==============================================================================
--- (empty file)
+++ trunk/boost/detail/yield_k.hpp 2008-03-27 18:20:11 EDT (Thu, 27 Mar 2008)
@@ -0,0 +1,132 @@
+#ifndef BOOST_DETAIL_YIELD_K_HPP_INCLUDED
+#define BOOST_DETAIL_YIELD_K_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//
+// boost/detail/yield_k.hpp
+//
+// Copyright (c) 2008 Peter Dimov
+//
+// 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>
+
+#if defined( WIN32 ) || defined( _WIN32 ) || defined( __WIN32__ )
+
+#if defined( BOOST_USE_WINDOWS_H )
+# include <windows.h>
+#endif
+
+#if defined(_MSC_VER) && _MSC_VER >= 1310
+ extern "C" void _mm_pause();
+#endif
+
+namespace boost
+{
+
+namespace detail
+{
+
+#if !defined( BOOST_USE_WINDOWS_H )
+ extern "C" void __stdcall Sleep( unsigned ms );
+#endif
+
+void yield( unsigned k )
+{
+ if( k < 4 )
+ {
+ }
+#if defined(_MSC_VER) && _MSC_VER >= 1310
+ else if( k < 16 )
+ {
+ _mm_pause();
+ }
+#endif
+ else if( k < 32 )
+ {
+ Sleep( 0 );
+ }
+ else
+ {
+ Sleep( 1 );
+ }
+}
+
+} // namespace detail
+
+} // namespace boost
+
+#elif defined( BOOST_HAS_PTHREADS )
+
+#include <sched.h>
+#include <time.h>
+
+namespace boost
+{
+
+namespace detail
+{
+
+void yield( unsigned k )
+{
+ if( k < 4 )
+ {
+ }
+#if defined( __GNUC__ ) && ( defined( __i386__ ) || defined( __x86_64__ ) )
+ else if( k < 16 )
+ {
+ __asm__ __volatile__( "rep; nop" ::: "memory" );
+ }
+#endif
+ else if( k < 32 || k & 1 )
+ {
+ sched_yield();
+ }
+ else
+ {
+ struct timespec rqtp = { 0 };
+
+ 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_DETAIL_YIELD_K_HPP_INCLUDED
Modified: trunk/libs/smart_ptr/test/Jamfile.v2
==============================================================================
--- trunk/libs/smart_ptr/test/Jamfile.v2 (original)
+++ trunk/libs/smart_ptr/test/Jamfile.v2 2008-03-27 18:20:11 EDT (Thu, 27 Mar 2008)
@@ -37,5 +37,6 @@
[ compile-fail scoped_array_eq_fail.cpp ]
[ run esft_regtest.cpp ]
[ run esft_constructor_test.cpp ]
+ [ run yield_k_test.cpp ]
;
}
Added: trunk/libs/smart_ptr/test/yield_k_test.cpp
==============================================================================
--- (empty file)
+++ trunk/libs/smart_ptr/test/yield_k_test.cpp 2008-03-27 18:20:11 EDT (Thu, 27 Mar 2008)
@@ -0,0 +1,23 @@
+//
+// yield_k_test.cpp
+//
+// Copyright 2008 Peter Dimov
+//
+// 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/detail/yield_k.hpp>
+
+// Sanity check only
+
+int main()
+{
+ for( unsigned k = 0; k < 256; ++k )
+ {
+ boost::detail::yield( k );
+ }
+
+ return 0;
+}