forked from boostorg/smart_ptr
88 lines
1.5 KiB
C++
88 lines
1.5 KiB
C++
#ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_SYNC_HPP_INCLUDED
|
|
#define BOOST_SMART_PTR_DETAIL_SPINLOCK_SYNC_HPP_INCLUDED
|
|
|
|
// MS compatible compilers support #pragma once
|
|
|
|
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
|
|
# pragma once
|
|
#endif
|
|
|
|
//
|
|
// Copyright (c) 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/smart_ptr/detail/yield_k.hpp>
|
|
|
|
#if defined( __ia64__ ) && defined( __INTEL_COMPILER )
|
|
# include <ia64intrin.h>
|
|
#endif
|
|
|
|
namespace boost
|
|
{
|
|
|
|
namespace detail
|
|
{
|
|
|
|
class spinlock
|
|
{
|
|
public:
|
|
|
|
int v_;
|
|
|
|
public:
|
|
|
|
bool try_lock()
|
|
{
|
|
int r = __sync_lock_test_and_set( &v_, 1 );
|
|
return r == 0;
|
|
}
|
|
|
|
void lock()
|
|
{
|
|
for( unsigned k = 0; !try_lock(); ++k )
|
|
{
|
|
boost::detail::yield( k );
|
|
}
|
|
}
|
|
|
|
void unlock()
|
|
{
|
|
__sync_lock_release( &v_ );
|
|
}
|
|
|
|
public:
|
|
|
|
class scoped_lock
|
|
{
|
|
private:
|
|
|
|
spinlock & sp_;
|
|
|
|
scoped_lock( scoped_lock const & );
|
|
scoped_lock & operator=( scoped_lock const & );
|
|
|
|
public:
|
|
|
|
explicit scoped_lock( spinlock & sp ): sp_( sp )
|
|
{
|
|
sp.lock();
|
|
}
|
|
|
|
~scoped_lock()
|
|
{
|
|
sp_.unlock();
|
|
}
|
|
};
|
|
};
|
|
|
|
} // namespace detail
|
|
} // namespace boost
|
|
|
|
#define BOOST_DETAIL_SPINLOCK_INIT {0}
|
|
|
|
#endif // #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_SYNC_HPP_INCLUDED
|