boost::detail::spinlock added.

[SVN r43950]

include/boost/detail/spinlock.hpp

@@ -0,0 +1,43 @@
+#ifndef BOOST_DETAIL_SPINLOCK_HPP_INCLUDED
+#define BOOST_DETAIL_SPINLOCK_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//
+//  boost/detail/spinlock.hpp
+//
+//  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)
+//
+//  struct spinlock
+//  {
+//      void lock();
+//      bool try_lock();
+//      void unlock();
+//
+//      class scoped_lock;
+//  };
+//
+//  #define BOOST_DETAIL_SPINLOCK_INIT <unspecified>
+//
+
+#include <boost/config.hpp>
+
+#if defined(__GNUC__) && ( __GNUC__ * 100 + __GNUC_MINOR__ >= 401 )
+#  include <boost/detail/spinlock_sync.hpp>
+#elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
+#  include <boost/detail/spinlock_w32.hpp>
+#elif defined(BOOST_HAS_PTHREADS)
+#  include <boost/detail/spinlock_pt.hpp>
+#else
+#  error Unrecognized threading platform
+#endif
+
+#endif // #ifndef BOOST_DETAIL_SPINLOCK_HPP_INCLUDED

include/boost/detail/spinlock_pt.hpp

@@ -0,0 +1,79 @@
+#ifndef BOOST_DETAIL_SPINLOCK_PT_HPP_INCLUDED
+#define BOOST_DETAIL_SPINLOCK_PT_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 <pthread.h>
+
+namespace boost
+{
+
+namespace detail
+{
+
+class spinlock
+{
+public:
+
+    pthread_mutex_t v_;
+
+public:
+
+    bool try_lock()
+    {
+        return pthread_mutex_trylock( &v_ ) == 0;
+    }
+
+    void lock()
+    {
+        pthread_mutex_lock( &v_ );
+    }
+
+    void unlock()
+    {
+        pthread_mutex_unlock( &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 { PTHREAD_MUTEX_INITIALIZER }
+
+#endif // #ifndef BOOST_DETAIL_SPINLOCK_PT_HPP_INCLUDED

include/boost/detail/spinlock_sync.hpp

@@ -0,0 +1,83 @@
+#ifndef BOOST_DETAIL_SPINLOCK_SYNC_HPP_INCLUDED
+#define BOOST_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/detail/yield_k.hpp>
+
+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_DETAIL_SPINLOCK_SYNC_HPP_INCLUDED

include/boost/detail/spinlock_w32.hpp

@@ -0,0 +1,98 @@
+#ifndef BOOST_DETAIL_SPINLOCK_W32_HPP_INCLUDED
+#define BOOST_DETAIL_SPINLOCK_W32_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/detail/interlocked.hpp>
+#include <boost/detail/yield_k.hpp>
+
+#if defined( _MSC_VER ) && _MSC_VER >= 1310
+  extern "C" void _ReadWriteBarrier();
+# pragma intrinsic( _ReadWriteBarrier )
+#endif
+
+namespace boost
+{
+
+namespace detail
+{
+
+class spinlock
+{
+public:
+
+    long v_;
+
+public:
+
+    bool try_lock()
+    {
+        long r = BOOST_INTERLOCKED_EXCHANGE( &v_, 1 );
+
+#if defined( _MSC_VER ) && _MSC_VER >= 1310
+        _ReadWriteBarrier();
+#endif
+
+        return r == 0;
+    }
+
+    void lock()
+    {
+        for( unsigned k = 0; !try_lock(); ++k )
+        {
+            boost::detail::yield( k );
+        }
+    }
+
+    void unlock()
+    {
+#if defined( _MSC_VER ) && _MSC_VER >= 1310
+        _ReadWriteBarrier();
+#endif
+
+        *const_cast< long volatile* >( &v_ ) = 0;
+    }
+
+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_DETAIL_SPINLOCK_W32_HPP_INCLUDED

test/Jamfile.v2

@@ -38,5 +38,6 @@ import testing ;
           [ run esft_regtest.cpp ]
           [ run esft_constructor_test.cpp ]
           [ run yield_k_test.cpp ]
+          [ run spinlock_test.cpp ]
         ;
 }

test/spinlock_test.cpp

@@ -0,0 +1,46 @@
+//
+// spinlock_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/spinlock.hpp>
+#include <boost/detail/lightweight_test.hpp>
+
+// Sanity check only
+
+static boost::detail::spinlock sp = BOOST_DETAIL_SPINLOCK_INIT;
+static boost::detail::spinlock sp2 = BOOST_DETAIL_SPINLOCK_INIT;
+
+int main()
+{
+    BOOST_TEST( sp.try_lock() );
+    BOOST_TEST( !sp.try_lock() );
+    BOOST_TEST( sp2.try_lock() );
+    BOOST_TEST( !sp.try_lock() );
+    BOOST_TEST( !sp2.try_lock() );
+    sp.unlock();
+    sp2.unlock();
+
+    sp.lock();
+    BOOST_TEST( !sp.try_lock() );
+    sp2.lock();
+    BOOST_TEST( !sp.try_lock() );
+    BOOST_TEST( !sp2.try_lock() );
+    sp.unlock();
+    sp2.unlock();
+
+    {
+        boost::detail::spinlock::scoped_lock lock( sp );
+        BOOST_TEST( !sp.try_lock() );
+        boost::detail::spinlock::scoped_lock lock2( sp2 );
+        BOOST_TEST( !sp.try_lock() );
+        BOOST_TEST( !sp2.try_lock() );
+    }
+
+    return boost::report_errors();
+}