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797 lines
26 KiB
C++
797 lines
26 KiB
C++
// Copyright (C) 2008-2013 Tim Blechmann
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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#ifndef BOOST_LOCKFREE_STACK_HPP_INCLUDED
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#define BOOST_LOCKFREE_STACK_HPP_INCLUDED
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#include <boost/assert.hpp>
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#include <boost/checked_delete.hpp>
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#include <boost/core/no_exceptions_support.hpp>
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#include <boost/integer_traits.hpp>
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#include <boost/static_assert.hpp>
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#include <boost/tuple/tuple.hpp>
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#include <boost/type_traits/is_copy_constructible.hpp>
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#include <boost/lockfree/detail/atomic.hpp>
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#include <boost/lockfree/detail/copy_payload.hpp>
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#include <boost/lockfree/detail/freelist.hpp>
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#include <boost/lockfree/detail/parameter.hpp>
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#include <boost/lockfree/detail/tagged_ptr.hpp>
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#include <boost/lockfree/lockfree_forward.hpp>
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#ifdef BOOST_HAS_PRAGMA_ONCE
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#pragma once
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#endif
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namespace boost {
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namespace lockfree {
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namespace detail {
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typedef parameter::parameters<boost::parameter::optional<tag::allocator>,
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boost::parameter::optional<tag::capacity>
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> stack_signature;
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}
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/** The stack class provides a multi-writer/multi-reader stack, pushing and popping is lock-free,
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* construction/destruction has to be synchronized. It uses a freelist for memory management,
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* freed nodes are pushed to the freelist and not returned to the OS before the stack is destroyed.
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*
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* \b Policies:
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*
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* - \c boost::lockfree::fixed_sized<>, defaults to \c boost::lockfree::fixed_sized<false> <br>
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* Can be used to completely disable dynamic memory allocations during push in order to ensure lockfree behavior.<br>
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* If the data structure is configured as fixed-sized, the internal nodes are stored inside an array and they are addressed
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* by array indexing. This limits the possible size of the stack to the number of elements that can be addressed by the index
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* type (usually 2**16-2), but on platforms that lack double-width compare-and-exchange instructions, this is the best way
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* to achieve lock-freedom.
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*
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* - \c boost::lockfree::capacity<>, optional <br>
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* If this template argument is passed to the options, the size of the stack is set at compile-time. <br>
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* It this option implies \c fixed_sized<true>
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*
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* - \c boost::lockfree::allocator<>, defaults to \c boost::lockfree::allocator<std::allocator<void>> <br>
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* Specifies the allocator that is used for the internal freelist
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*
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* \b Requirements:
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* - T must have a copy constructor
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* */
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#ifdef BOOST_NO_CXX11_VARIADIC_TEMPLATES
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template <typename T, class A0, class A1, class A2>
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#else
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template <typename T, typename ...Options>
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#endif
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class stack
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{
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private:
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#ifndef BOOST_DOXYGEN_INVOKED
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BOOST_STATIC_ASSERT(boost::is_copy_constructible<T>::value);
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#ifdef BOOST_NO_CXX11_VARIADIC_TEMPLATES
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typedef typename detail::stack_signature::bind<A0, A1, A2>::type bound_args;
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#else
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typedef typename detail::stack_signature::bind<Options...>::type bound_args;
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#endif
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static const bool has_capacity = detail::extract_capacity<bound_args>::has_capacity;
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static const size_t capacity = detail::extract_capacity<bound_args>::capacity;
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static const bool fixed_sized = detail::extract_fixed_sized<bound_args>::value;
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static const bool node_based = !(has_capacity || fixed_sized);
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static const bool compile_time_sized = has_capacity;
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struct node
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{
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node(T const & val):
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v(val)
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{}
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typedef typename detail::select_tagged_handle<node, node_based>::handle_type handle_t;
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handle_t next;
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const T v;
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};
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typedef typename detail::extract_allocator<bound_args, node>::type node_allocator;
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typedef typename detail::select_freelist<node, node_allocator, compile_time_sized, fixed_sized, capacity>::type pool_t;
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typedef typename pool_t::tagged_node_handle tagged_node_handle;
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// check compile-time capacity
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BOOST_STATIC_ASSERT((mpl::if_c<has_capacity,
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mpl::bool_<capacity - 1 < boost::integer_traits<boost::uint16_t>::const_max>,
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mpl::true_
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>::type::value));
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struct implementation_defined
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{
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typedef node_allocator allocator;
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typedef std::size_t size_type;
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};
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#endif
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BOOST_DELETED_FUNCTION(stack(stack const&))
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BOOST_DELETED_FUNCTION(stack& operator= (stack const&))
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public:
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typedef T value_type;
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typedef typename implementation_defined::allocator allocator;
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typedef typename implementation_defined::size_type size_type;
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/**
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* \return true, if implementation is lock-free.
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*
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* \warning It only checks, if the top stack node and the freelist can be modified in a lock-free manner.
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* On most platforms, the whole implementation is lock-free, if this is true. Using c++0x-style atomics,
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* there is no possibility to provide a completely accurate implementation, because one would need to test
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* every internal node, which is impossible if further nodes will be allocated from the operating system.
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*
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* */
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bool is_lock_free (void) const
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{
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return tos.is_lock_free() && pool.is_lock_free();
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}
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//! Construct stack
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// @{
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stack(void):
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pool(node_allocator(), capacity)
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{
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BOOST_ASSERT(has_capacity);
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initialize();
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}
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template <typename U>
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explicit stack(typename node_allocator::template rebind<U>::other const & alloc):
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pool(alloc, capacity)
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{
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BOOST_STATIC_ASSERT(has_capacity);
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initialize();
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}
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explicit stack(allocator const & alloc):
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pool(alloc, capacity)
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{
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BOOST_ASSERT(has_capacity);
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initialize();
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}
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// @}
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//! Construct stack, allocate n nodes for the freelist.
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// @{
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explicit stack(size_type n):
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pool(node_allocator(), n)
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{
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BOOST_ASSERT(!has_capacity);
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initialize();
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}
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template <typename U>
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stack(size_type n, typename node_allocator::template rebind<U>::other const & alloc):
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pool(alloc, n)
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{
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BOOST_STATIC_ASSERT(!has_capacity);
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initialize();
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}
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// @}
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/** Allocate n nodes for freelist
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*
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* \pre only valid if no capacity<> argument given
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* \note thread-safe, may block if memory allocator blocks
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*
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* */
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void reserve(size_type n)
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{
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BOOST_STATIC_ASSERT(!has_capacity);
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pool.template reserve<true>(n);
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}
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/** Allocate n nodes for freelist
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*
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* \pre only valid if no capacity<> argument given
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* \note not thread-safe, may block if memory allocator blocks
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*
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* */
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void reserve_unsafe(size_type n)
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{
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BOOST_STATIC_ASSERT(!has_capacity);
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pool.template reserve<false>(n);
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}
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/** Destroys stack, free all nodes from freelist.
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*
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* \note not thread-safe
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*
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* */
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~stack(void)
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{
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T dummy;
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while(unsynchronized_pop(dummy))
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{}
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}
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private:
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#ifndef BOOST_DOXYGEN_INVOKED
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void initialize(void)
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{
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tos.store(tagged_node_handle(pool.null_handle(), 0));
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}
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void link_nodes_atomic(node * new_top_node, node * end_node)
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{
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tagged_node_handle old_tos = tos.load(detail::memory_order_relaxed);
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for (;;) {
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tagged_node_handle new_tos (pool.get_handle(new_top_node), old_tos.get_tag());
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end_node->next = pool.get_handle(old_tos);
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if (tos.compare_exchange_weak(old_tos, new_tos))
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break;
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}
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}
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void link_nodes_unsafe(node * new_top_node, node * end_node)
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{
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tagged_node_handle old_tos = tos.load(detail::memory_order_relaxed);
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tagged_node_handle new_tos (pool.get_handle(new_top_node), old_tos.get_tag());
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end_node->next = pool.get_pointer(old_tos);
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tos.store(new_tos, memory_order_relaxed);
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}
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template <bool Threadsafe, bool Bounded, typename ConstIterator>
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tuple<node*, node*> prepare_node_list(ConstIterator begin, ConstIterator end, ConstIterator & ret)
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{
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ConstIterator it = begin;
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node * end_node = pool.template construct<Threadsafe, Bounded>(*it++);
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if (end_node == NULL) {
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ret = begin;
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return make_tuple<node*, node*>(NULL, NULL);
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}
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node * new_top_node = end_node;
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end_node->next = NULL;
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BOOST_TRY {
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/* link nodes */
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for (; it != end; ++it) {
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node * newnode = pool.template construct<Threadsafe, Bounded>(*it);
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if (newnode == NULL)
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break;
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newnode->next = new_top_node;
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new_top_node = newnode;
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}
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} BOOST_CATCH (...) {
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for (node * current_node = new_top_node; current_node != NULL;) {
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node * next = current_node->next;
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pool.template destruct<Threadsafe>(current_node);
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current_node = next;
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}
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BOOST_RETHROW;
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}
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BOOST_CATCH_END
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ret = it;
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return make_tuple(new_top_node, end_node);
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}
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#endif
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public:
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/** Pushes object t to the stack.
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*
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* \post object will be pushed to the stack, if internal node can be allocated
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* \returns true, if the push operation is successful.
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*
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* \note Thread-safe. If internal memory pool is exhausted and the memory pool is not fixed-sized, a new node will be allocated
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* from the OS. This may not be lock-free.
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* \throws if memory allocator throws
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* */
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bool push(T const & v)
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{
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return do_push<false>(v);
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}
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/** Pushes object t to the stack.
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*
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* \post object will be pushed to the stack, if internal node can be allocated
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* \returns true, if the push operation is successful.
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*
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* \note Thread-safe and non-blocking. If internal memory pool is exhausted, the push operation will fail
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* */
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bool bounded_push(T const & v)
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{
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return do_push<true>(v);
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}
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#ifndef BOOST_DOXYGEN_INVOKED
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private:
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template <bool Bounded>
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bool do_push(T const & v)
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{
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node * newnode = pool.template construct<true, Bounded>(v);
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if (newnode == 0)
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return false;
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link_nodes_atomic(newnode, newnode);
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return true;
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}
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template <bool Bounded, typename ConstIterator>
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ConstIterator do_push(ConstIterator begin, ConstIterator end)
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{
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node * new_top_node;
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node * end_node;
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ConstIterator ret;
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tie(new_top_node, end_node) = prepare_node_list<true, Bounded>(begin, end, ret);
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if (new_top_node)
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link_nodes_atomic(new_top_node, end_node);
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return ret;
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}
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public:
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#endif
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/** Pushes as many objects from the range [begin, end) as freelist node can be allocated.
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*
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* \return iterator to the first element, which has not been pushed
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*
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* \note Operation is applied atomically
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* \note Thread-safe. If internal memory pool is exhausted and the memory pool is not fixed-sized, a new node will be allocated
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* from the OS. This may not be lock-free.
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* \throws if memory allocator throws
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*/
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template <typename ConstIterator>
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ConstIterator push(ConstIterator begin, ConstIterator end)
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{
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return do_push<false, ConstIterator>(begin, end);
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}
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/** Pushes as many objects from the range [begin, end) as freelist node can be allocated.
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*
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* \return iterator to the first element, which has not been pushed
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*
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* \note Operation is applied atomically
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* \note Thread-safe and non-blocking. If internal memory pool is exhausted, the push operation will fail
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* \throws if memory allocator throws
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*/
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template <typename ConstIterator>
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ConstIterator bounded_push(ConstIterator begin, ConstIterator end)
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{
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return do_push<true, ConstIterator>(begin, end);
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}
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/** Pushes object t to the stack.
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*
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* \post object will be pushed to the stack, if internal node can be allocated
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* \returns true, if the push operation is successful.
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*
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* \note Not thread-safe. If internal memory pool is exhausted and the memory pool is not fixed-sized, a new node will be allocated
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* from the OS. This may not be lock-free.
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* \throws if memory allocator throws
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* */
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bool unsynchronized_push(T const & v)
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{
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node * newnode = pool.template construct<false, false>(v);
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if (newnode == 0)
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return false;
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link_nodes_unsafe(newnode, newnode);
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return true;
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}
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/** Pushes as many objects from the range [begin, end) as freelist node can be allocated.
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*
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* \return iterator to the first element, which has not been pushed
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*
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* \note Not thread-safe. If internal memory pool is exhausted and the memory pool is not fixed-sized, a new node will be allocated
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* from the OS. This may not be lock-free.
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* \throws if memory allocator throws
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*/
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template <typename ConstIterator>
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ConstIterator unsynchronized_push(ConstIterator begin, ConstIterator end)
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{
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node * new_top_node;
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node * end_node;
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ConstIterator ret;
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tie(new_top_node, end_node) = prepare_node_list<false, false>(begin, end, ret);
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if (new_top_node)
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link_nodes_unsafe(new_top_node, end_node);
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return ret;
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}
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/** Pops object from stack.
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*
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* \post if pop operation is successful, object will be copied to ret.
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* \returns true, if the pop operation is successful, false if stack was empty.
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*
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* \note Thread-safe and non-blocking
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*
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* */
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bool pop(T & ret)
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{
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return pop<T>(ret);
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}
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/** Pops object from stack.
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*
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* \pre type T must be convertible to U
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* \post if pop operation is successful, object will be copied to ret.
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* \returns true, if the pop operation is successful, false if stack was empty.
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*
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* \note Thread-safe and non-blocking
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*
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* */
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template <typename U>
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bool pop(U & ret)
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{
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BOOST_STATIC_ASSERT((boost::is_convertible<T, U>::value));
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detail::consume_via_copy<U> consumer(ret);
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return consume_one(consumer);
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}
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/** Pops object from stack.
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*
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* \post if pop operation is successful, object will be copied to ret.
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* \returns true, if the pop operation is successful, false if stack was empty.
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*
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* \note Not thread-safe, but non-blocking
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*
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* */
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bool unsynchronized_pop(T & ret)
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{
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return unsynchronized_pop<T>(ret);
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}
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/** Pops object from stack.
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*
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* \pre type T must be convertible to U
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* \post if pop operation is successful, object will be copied to ret.
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* \returns true, if the pop operation is successful, false if stack was empty.
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*
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* \note Not thread-safe, but non-blocking
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*
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* */
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template <typename U>
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bool unsynchronized_pop(U & ret)
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{
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BOOST_STATIC_ASSERT((boost::is_convertible<T, U>::value));
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tagged_node_handle old_tos = tos.load(detail::memory_order_relaxed);
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node * old_tos_pointer = pool.get_pointer(old_tos);
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if (!pool.get_pointer(old_tos))
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return false;
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node * new_tos_ptr = pool.get_pointer(old_tos_pointer->next);
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tagged_node_handle new_tos(pool.get_handle(new_tos_ptr), old_tos.get_next_tag());
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tos.store(new_tos, memory_order_relaxed);
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detail::copy_payload(old_tos_pointer->v, ret);
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pool.template destruct<false>(old_tos);
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return true;
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}
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/** consumes one element via a functor
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*
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* pops one element from the stack and applies the functor on this object
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*
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* \returns true, if one element was consumed
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*
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* \note Thread-safe and non-blocking, if functor is thread-safe and non-blocking
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* */
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template <typename Functor>
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bool consume_one(Functor & f)
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{
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tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
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for (;;) {
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node * old_tos_pointer = pool.get_pointer(old_tos);
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if (!old_tos_pointer)
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return false;
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tagged_node_handle new_tos(old_tos_pointer->next, old_tos.get_next_tag());
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if (tos.compare_exchange_weak(old_tos, new_tos)) {
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f(old_tos_pointer->v);
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pool.template destruct<true>(old_tos);
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return true;
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}
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}
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}
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/// \copydoc boost::lockfree::stack::consume_one(Functor & rhs)
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template <typename Functor>
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bool consume_one(Functor const & f)
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{
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tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
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for (;;) {
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node * old_tos_pointer = pool.get_pointer(old_tos);
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if (!old_tos_pointer)
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return false;
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tagged_node_handle new_tos(old_tos_pointer->next, old_tos.get_next_tag());
|
|
|
|
if (tos.compare_exchange_weak(old_tos, new_tos)) {
|
|
f(old_tos_pointer->v);
|
|
pool.template destruct<true>(old_tos);
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
/** consumes all elements via a functor
|
|
*
|
|
* sequentially pops all elements from the stack and applies the functor on each object
|
|
*
|
|
* \returns number of elements that are consumed
|
|
*
|
|
* \note Thread-safe and non-blocking, if functor is thread-safe and non-blocking
|
|
* */
|
|
template <typename Functor>
|
|
size_t consume_all(Functor & f)
|
|
{
|
|
size_t element_count = 0;
|
|
while (consume_one(f))
|
|
element_count += 1;
|
|
|
|
return element_count;
|
|
}
|
|
|
|
/// \copydoc boost::lockfree::stack::consume_all(Functor & rhs)
|
|
template <typename Functor>
|
|
size_t consume_all(Functor const & f)
|
|
{
|
|
size_t element_count = 0;
|
|
while (consume_one(f))
|
|
element_count += 1;
|
|
|
|
return element_count;
|
|
}
|
|
|
|
/** consumes all elements via a functor
|
|
*
|
|
* atomically pops all elements from the stack and applies the functor on each object
|
|
*
|
|
* \returns number of elements that are consumed
|
|
*
|
|
* \note Thread-safe and non-blocking, if functor is thread-safe and non-blocking
|
|
* */
|
|
template <typename Functor>
|
|
size_t consume_all_atomic(Functor & f)
|
|
{
|
|
size_t element_count = 0;
|
|
tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
|
|
|
|
for (;;) {
|
|
node * old_tos_pointer = pool.get_pointer(old_tos);
|
|
if (!old_tos_pointer)
|
|
return 0;
|
|
|
|
tagged_node_handle new_tos(pool.null_handle(), old_tos.get_next_tag());
|
|
|
|
if (tos.compare_exchange_weak(old_tos, new_tos))
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle nodes_to_consume = old_tos;
|
|
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_to_consume);
|
|
f(node_pointer->v);
|
|
element_count += 1;
|
|
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
if (!next_node) {
|
|
pool.template destruct<true>(nodes_to_consume);
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_to_consume.get_next_tag());
|
|
pool.template destruct<true>(nodes_to_consume);
|
|
nodes_to_consume = next;
|
|
}
|
|
|
|
return element_count;
|
|
}
|
|
|
|
/// \copydoc boost::lockfree::stack::consume_all_atomic(Functor & rhs)
|
|
template <typename Functor>
|
|
size_t consume_all_atomic(Functor const & f)
|
|
{
|
|
size_t element_count = 0;
|
|
tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
|
|
|
|
for (;;) {
|
|
node * old_tos_pointer = pool.get_pointer(old_tos);
|
|
if (!old_tos_pointer)
|
|
return 0;
|
|
|
|
tagged_node_handle new_tos(pool.null_handle(), old_tos.get_next_tag());
|
|
|
|
if (tos.compare_exchange_weak(old_tos, new_tos))
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle nodes_to_consume = old_tos;
|
|
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_to_consume);
|
|
f(node_pointer->v);
|
|
element_count += 1;
|
|
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
if (!next_node) {
|
|
pool.template destruct<true>(nodes_to_consume);
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_to_consume.get_next_tag());
|
|
pool.template destruct<true>(nodes_to_consume);
|
|
nodes_to_consume = next;
|
|
}
|
|
|
|
return element_count;
|
|
}
|
|
|
|
/** consumes all elements via a functor
|
|
*
|
|
* atomically pops all elements from the stack and applies the functor on each object in reversed order
|
|
*
|
|
* \returns number of elements that are consumed
|
|
*
|
|
* \note Thread-safe and non-blocking, if functor is thread-safe and non-blocking
|
|
* */
|
|
template <typename Functor>
|
|
size_t consume_all_atomic_reversed(Functor & f)
|
|
{
|
|
size_t element_count = 0;
|
|
tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
|
|
|
|
for (;;) {
|
|
node * old_tos_pointer = pool.get_pointer(old_tos);
|
|
if (!old_tos_pointer)
|
|
return 0;
|
|
|
|
tagged_node_handle new_tos(pool.null_handle(), old_tos.get_next_tag());
|
|
|
|
if (tos.compare_exchange_weak(old_tos, new_tos))
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle nodes_to_consume = old_tos;
|
|
|
|
node * last_node_pointer = NULL;
|
|
tagged_node_handle nodes_in_reversed_order;
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_to_consume);
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
node_pointer->next = pool.get_handle(last_node_pointer);
|
|
last_node_pointer = node_pointer;
|
|
|
|
if (!next_node) {
|
|
nodes_in_reversed_order = nodes_to_consume;
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_to_consume.get_next_tag());
|
|
nodes_to_consume = next;
|
|
}
|
|
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_in_reversed_order);
|
|
f(node_pointer->v);
|
|
element_count += 1;
|
|
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
if (!next_node) {
|
|
pool.template destruct<true>(nodes_in_reversed_order);
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_in_reversed_order.get_next_tag());
|
|
pool.template destruct<true>(nodes_in_reversed_order);
|
|
nodes_in_reversed_order = next;
|
|
}
|
|
|
|
return element_count;
|
|
}
|
|
|
|
/// \copydoc boost::lockfree::stack::consume_all_atomic_reversed(Functor & rhs)
|
|
template <typename Functor>
|
|
size_t consume_all_atomic_reversed(Functor const & f)
|
|
{
|
|
size_t element_count = 0;
|
|
tagged_node_handle old_tos = tos.load(detail::memory_order_consume);
|
|
|
|
for (;;) {
|
|
node * old_tos_pointer = pool.get_pointer(old_tos);
|
|
if (!old_tos_pointer)
|
|
return 0;
|
|
|
|
tagged_node_handle new_tos(pool.null_handle(), old_tos.get_next_tag());
|
|
|
|
if (tos.compare_exchange_weak(old_tos, new_tos))
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle nodes_to_consume = old_tos;
|
|
|
|
node * last_node_pointer = NULL;
|
|
tagged_node_handle nodes_in_reversed_order;
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_to_consume);
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
node_pointer->next = pool.get_handle(last_node_pointer);
|
|
last_node_pointer = node_pointer;
|
|
|
|
if (!next_node) {
|
|
nodes_in_reversed_order = nodes_to_consume;
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_to_consume.get_next_tag());
|
|
nodes_to_consume = next;
|
|
}
|
|
|
|
for(;;) {
|
|
node * node_pointer = pool.get_pointer(nodes_in_reversed_order);
|
|
f(node_pointer->v);
|
|
element_count += 1;
|
|
|
|
node * next_node = pool.get_pointer(node_pointer->next);
|
|
|
|
if (!next_node) {
|
|
pool.template destruct<true>(nodes_in_reversed_order);
|
|
break;
|
|
}
|
|
|
|
tagged_node_handle next(pool.get_handle(next_node), nodes_in_reversed_order.get_next_tag());
|
|
pool.template destruct<true>(nodes_in_reversed_order);
|
|
nodes_in_reversed_order = next;
|
|
}
|
|
|
|
return element_count;
|
|
}
|
|
/**
|
|
* \return true, if stack is empty.
|
|
*
|
|
* \note It only guarantees that at some point during the execution of the function the stack has been empty.
|
|
* It is rarely practical to use this value in program logic, because the stack can be modified by other threads.
|
|
* */
|
|
bool empty(void) const
|
|
{
|
|
return pool.get_pointer(tos.load()) == NULL;
|
|
}
|
|
|
|
private:
|
|
#ifndef BOOST_DOXYGEN_INVOKED
|
|
detail::atomic<tagged_node_handle> tos;
|
|
|
|
static const int padding_size = BOOST_LOCKFREE_CACHELINE_BYTES - sizeof(tagged_node_handle);
|
|
char padding[padding_size];
|
|
|
|
pool_t pool;
|
|
#endif
|
|
};
|
|
|
|
} /* namespace lockfree */
|
|
} /* namespace boost */
|
|
|
|
#endif /* BOOST_LOCKFREE_STACK_HPP_INCLUDED */
|