boost/smart_ptr/detail/spinlock_pool.hpp

   1 #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_POOL_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_DETAIL_SPINLOCK_POOL_HPP_INCLUDED
   3
   4 // MS compatible compilers support #pragma once
   5
   6 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
   7 # pragma once
   8 #endif
   9
  10 //
  11 //  boost/detail/spinlock_pool.hpp
  12 //
  13 //  Copyright (c) 2008 Peter Dimov
  14 //
  15 //  Distributed under the Boost Software License, Version 1.0.
  16 //  See accompanying file LICENSE_1_0.txt or copy at
  17 //  http://www.boost.org/LICENSE_1_0.txt)
  18 //
  19 //  spinlock_pool<0> is reserved for atomic<>, when/if it arrives
  20 //  spinlock_pool<1> is reserved for shared_ptr reference counts
  21 //  spinlock_pool<2> is reserved for shared_ptr atomic access
  22 //
  23
  24 #include <boost/config.hpp>
  25 #include <boost/smart_ptr/detail/spinlock.hpp>
  26 #include <cstddef>
  27
  28 namespace boost
  29 {
  30
  31 namespace detail
  32 {
  33
  34 template< int I > class spinlock_pool
  35 {
  36 private:
  37
  38     static spinlock pool_[ 41 ];
  39
  40 public:
  41
  42     static spinlock & spinlock_for( void const * pv )
  43     {
  44 #if defined(__VMS) && __INITIAL_POINTER_SIZE == 64
  45         std::size_t i = reinterpret_cast< unsigned long long >( pv ) % 41;
  46 #else
  47         std::size_t i = reinterpret_cast< std::size_t >( pv ) % 41;
  48 #endif
  49         return pool_[ i ];
  50     }
  51
  52     class scoped_lock
  53     {
  54     private:
  55
  56         spinlock & sp_;
  57
  58         scoped_lock( scoped_lock const & );
  59         scoped_lock & operator=( scoped_lock const & );
  60
  61     public:
  62
  63         explicit scoped_lock( void const * pv ): sp_( spinlock_for( pv ) )
  64         {
  65             sp_.lock();
  66         }
  67
  68         ~scoped_lock()
  69         {
  70             sp_.unlock();
  71         }
  72     };
  73 };
  74
  75 template< int I > spinlock spinlock_pool< I >::pool_[ 41 ] =
  76 {
  77     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  78     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  79     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  80     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  81     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  82     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  83     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  84     BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT, BOOST_DETAIL_SPINLOCK_INIT,
  85     BOOST_DETAIL_SPINLOCK_INIT
  86 };
  87
  88 } // namespace detail
  89 } // namespace boost
  90
  91 #endif // #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_POOL_HPP_INCLUDED