-//$$CDS-header$$
+/*
+ This file is a part of libcds - Concurrent Data Structures library
-#ifndef __CDS_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
-#define __CDS_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
+ (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2016
+
+ Source code repo: http://github.com/khizmax/libcds/
+ Download: http://sourceforge.net/projects/libcds/files/
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef CDSLIB_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
+#define CDSLIB_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
#include <cds/container/details/ellen_bintree_base.h>
#include <cds/intrusive/ellen_bintree_rcu.h>
the priority value plus some uniformly distributed random value.
@warning Recall the tree is <b>unbalanced</b>. The complexity of operations is <tt>O(log N)</tt>
- for uniformly distributed random keys, but in worst case the complexity is <tt>O(N)</tt>.
+ for uniformly distributed random keys, but in the worst case the complexity is <tt>O(N)</tt>.
@note In the current implementation we do not use helping technique described in original paper.
So, the current implementation is near to fine-grained lock-based tree.
- \p RCU - one of \ref cds_urcu_gc "RCU type"
- \p Key - key type
- \p T - value type to be stored in tree's leaf nodes.
- - \p Traits - type traits. See ellen_bintree::type_traits for explanation.
-
- It is possible to declare option-based tree with ellen_bintree::make_map_traits metafunction
- instead of \p Traits template argument.
- Template argument list \p Options of ellen_bintree::make_map_traits metafunction are:
- - opt::compare - key compare functor. No default functor is provided.
- If the option is not specified, \p %opt::less is used.
- - opt::less - specifies binary predicate used for key compare. At least \p %opt::compare or \p %opt::less should be defined.
- - opt::item_counter - the type of item counting feature. Default is \ref atomicity::empty_item_counter that is no item counting.
- - opt::memory_model - C++ memory ordering model. Can be opt::v::relaxed_ordering (relaxed memory model, the default)
- or opt::v::sequential_consistent (sequentially consisnent memory model).
- - opt::allocator - the allocator used for \ref ellen_bintree::map_node "leaf nodes" which contains data.
- Default is \ref CDS_DEFAULT_ALLOCATOR.
- - opt::node_allocator - the allocator used for \ref ellen_bintree::internal_node "internal nodes".
- Default is \ref CDS_DEFAULT_ALLOCATOR.
- - ellen_bintree::update_desc_allocator - an allocator of \ref ellen_bintree::update_desc "update descriptors",
- default is \ref CDS_DEFAULT_ALLOCATOR.
- Note that update descriptor is helping data structure with short lifetime and it is good candidate for pooling.
- The number of simultaneously existing descriptors is a relatively small number limited the number of threads
- working with the tree and RCU buffer size.
- Therefore, a bounded lock-free container like \p cds::container::VyukovMPMCCycleQueue is good choice for the free-list
- of update descriptors, see cds::memory::vyukov_queue_pool free-list implementation.
- Also notice that size of update descriptor is not dependent on the type of data
- stored in the tree so single free-list object can be used for several EllenBinTree-based object.
- - opt::stat - internal statistics. Available types: ellen_bintree::stat, ellen_bintree::empty_stat (the default)
- - opt::rcu_check_deadlock - a deadlock checking policy. Default is opt::v::rcu_throw_deadlock
- - opt::copy_policy - key copy policy defines a functor to copy leaf node's key to internal node.
- By default, assignment operator is used.
- The copy functor interface is:
- \code
- struct copy_functor {
- void operator()( Key& dest, Key const& src );
- };
- \endcode
+ - \p Traits - map traits, default is \p ellen_bintree::traits.
+ It is possible to declare option-based tree with \p ellen_bintree::make_map_traits metafunction
+ instead of \p Traits template argument.
@note Before including <tt><cds/container/ellen_bintree_map_rcu.h></tt> you should include appropriate RCU header file,
see \ref cds_urcu_gc "RCU type" for list of existing RCU class and corresponding header files.
typename Key,
typename T,
#ifdef CDS_DOXYGEN_INVOKED
- class Traits = ellen_bintree::type_traits
+ class Traits = ellen_bintree::traits
#else
class Traits
#endif
typedef typename maker::type base_class;
//@endcond
public:
- typedef cds::urcu::gc<RCU> gc ; ///< RCU Garbage collector
- typedef Key key_type ; ///< type of a key stored in the map
- typedef T mapped_type ; ///< type of value stored in the map
- typedef std::pair< key_type const, mapped_type > value_type ; ///< Key-value pair stored in leaf node of the mp
- typedef Traits options ; ///< Traits template parameter
+ typedef cds::urcu::gc<RCU> gc; ///< RCU Garbage collector
+ typedef Key key_type; ///< type of a key stored in the map
+ typedef T mapped_type; ///< type of value stored in the map
+ typedef std::pair< key_type const, mapped_type > value_type; ///< Key-value pair stored in leaf node of the mp
+ typedef Traits traits; ///< Traits template parameter
+
+ static_assert( std::is_default_constructible<key_type>::value, "Key should be default constructible type" );
# ifdef CDS_DOXYGEN_INVOKED
- typedef implementation_defined key_comparator ; ///< key compare functor based on opt::compare and opt::less option setter.
+ typedef implementation_defined key_comparator ; ///< key compare functor based on \p Traits::compare and \p Traits::less
# else
- typedef typename maker::intrusive_type_traits::compare key_comparator;
+ typedef typename maker::intrusive_traits::compare key_comparator;
# endif
- typedef typename base_class::item_counter item_counter ; ///< Item counting policy used
- typedef typename base_class::memory_model memory_model ; ///< Memory ordering. See cds::opt::memory_model option
- typedef typename base_class::node_allocator node_allocator_type ; ///< allocator for maintaining internal node
- typedef typename base_class::stat stat ; ///< internal statistics type
- typedef typename base_class::rcu_check_deadlock rcu_check_deadlock ; ///< Deadlock checking policy
- typedef typename options::copy_policy copy_policy ; ///< key copy policy
-
- typedef typename options::allocator allocator_type ; ///< Allocator for leaf nodes
- typedef typename base_class::node_allocator node_allocator ; ///< Internal node allocator
- typedef typename base_class::update_desc_allocator update_desc_allocator ; ///< Update descriptor allocator
+ typedef typename base_class::item_counter item_counter; ///< Item counting policy
+ typedef typename base_class::memory_model memory_model; ///< Memory ordering, see \p cds::opt::memory_model option
+ typedef typename base_class::node_allocator node_allocator_type; ///< allocator for maintaining internal node
+ typedef typename base_class::stat stat; ///< internal statistics
+ typedef typename base_class::rcu_check_deadlock rcu_check_deadlock; ///< Deadlock checking policy
+ typedef typename traits::copy_policy copy_policy; ///< key copy policy
+ typedef typename traits::back_off back_off; ///< Back-off strategy
+
+ typedef typename traits::allocator allocator_type; ///< Allocator for leaf nodes
+ typedef typename base_class::node_allocator node_allocator; ///< Internal node allocator
+ typedef typename base_class::update_desc_allocator update_desc_allocator; ///< Update descriptor allocator
static CDS_CONSTEXPR const bool c_bExtractLockExternal = base_class::c_bExtractLockExternal; ///< Group of \p extract_xxx functions do not require external locking
typedef typename gc::scoped_lock rcu_lock ; ///< RCU scoped lock
/// pointer to extracted node
- typedef cds::urcu::exempt_ptr< gc, leaf_node, value_type, typename maker::intrusive_type_traits::disposer,
- cds::urcu::details::conventional_exempt_member_cast<leaf_node, value_type>
- > exempt_ptr;
+ using exempt_ptr = cds::urcu::exempt_ptr < gc, leaf_node, value_type, typename maker::intrusive_traits::disposer,
+ cds::urcu::details::conventional_exempt_member_cast < leaf_node, value_type >
+ >;
public:
/// Default constructor
The function creates a node with \p key and default value, and then inserts the node created into the map.
Preconditions:
- - The \ref key_type should be constructible from a value of type \p K.
- In trivial case, \p K is equal to \ref key_type.
- - The \ref mapped_type should be default-constructible.
+ - The \p key_type should be constructible from a value of type \p K.
+ - The \p mapped_type should be default-constructible.
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() can be called. RCU should not be locked.
Returns \p true if inserting successful, \p false otherwise.
*/
template <typename K>
bool insert( K const& key )
{
- return insert_key( key, [](value_type&){} );
+ return insert_with( key, [](value_type&){} );
}
/// Inserts new node
and then inserts the node created into the map.
Preconditions:
- - The \ref key_type should be constructible from \p key of type \p K.
- - The \ref value_type should be constructible from \p val of type \p V.
+ - The \p key_type should be constructible from \p key of type \p K.
+ - The \p value_type should be constructible from \p val of type \p V.
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() method can be called. RCU should not be locked.
Returns \p true if \p val is inserted into the map, \p false otherwise.
*/
This can be useful if complete initialization of object of \p value_type is heavyweight and
it is preferable that the initialization should be completed only if inserting is successful.
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() method can be called. RCU should not be locked.
*/
template <typename K, typename Func>
- bool insert_key( const K& key, Func func )
+ bool insert_with( K const& key, Func func )
{
scoped_node_ptr pNode( cxx_leaf_node_allocator().New( key ));
if ( base_class::insert( *pNode, [&func]( leaf_node& item ) { func( item.m_Value ); } )) {
return false;
}
- /// For key \p key inserts data of type \ref value_type constructed with <tt>std::forward<Args>(args)...</tt>
+ /// For key \p key inserts data of type \p value_type created in-place from \p args
/**
Returns \p true if inserting successful, \p false otherwise.
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() method can be called. RCU should not be locked.
*/
template <typename K, typename... Args>
bool emplace( K&& key, Args&&... args )
{
- scoped_node_ptr pNode( cxx_leaf_node_allocator().New( std::forward<K>(key), std::forward<Args>(args)... ));
+ scoped_node_ptr pNode( cxx_leaf_node_allocator().MoveNew( key_type( std::forward<K>(key)), mapped_type( std::forward<Args>(args)... )));
if ( base_class::insert( *pNode )) {
pNode.release();
return true;
return false;
}
- /// Ensures that the \p key exists in the map
+ /// Updates the node
/**
The operation performs inserting or changing data with lock-free manner.
- If the \p key not found in the map, then the new item created from \p key
- is inserted into the map (note that in this case the \ref key_type should be
- constructible from type \p K).
+ If the item \p val is not found in the map, then \p val is inserted iff \p bAllowInsert is \p true.
Otherwise, the functor \p func is called with item found.
- The functor \p Func may be a function with signature:
- \code
- void func( bool bNew, value_type& item );
- \endcode
- or a functor:
+ The functor \p func signature is:
\code
struct my_functor {
void operator()( bool bNew, value_type& item );
with arguments:
- \p bNew - \p true if the item has been inserted, \p false otherwise
- - \p item - item of the list
+ - \p item - item of the map
- The functor may change any fields of the \p item.second that is \ref value_type.
+ The functor may change any fields of the \p item.second that is \p mapped_type;
+ however, \p func must guarantee that during changing no any other modifications
+ could be made on this item by concurrent threads.
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() method can be called. RCU should not be locked.
- Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
- \p second is true if new item has been added or \p false if the item with \p key
- already is in the list.
+ Returns std::pair<bool, bool> where \p first is \p true if operation is successful,
+ i.e. the node has been inserted or updated,
+ \p second is \p true if new item has been added or \p false if the item with \p key
+ already exists.
+
+ @warning See \ref cds_intrusive_item_creating "insert item troubleshooting"
*/
template <typename K, typename Func>
- std::pair<bool, bool> ensure( K const& key, Func func )
+ std::pair<bool, bool> update( K const& key, Func func, bool bAllowInsert = true )
{
scoped_node_ptr pNode( cxx_leaf_node_allocator().New( key ));
- std::pair<bool, bool> res = base_class::ensure( *pNode,
- [&func](bool bNew, leaf_node& item, leaf_node const& ){ func( bNew, item.m_Value ); }
+ std::pair<bool, bool> res = base_class::update( *pNode,
+ [&func](bool bNew, leaf_node& item, leaf_node const& ){ func( bNew, item.m_Value ); },
+ bAllowInsert
);
if ( res.first && res.second )
pNode.release();
return res;
}
+ //@cond
+ template <typename K, typename Func>
+ CDS_DEPRECATED("ensure() is deprecated, use update()")
+ std::pair<bool, bool> ensure( K const& key, Func func )
+ {
+ return update( key, func, true );
+ }
+ //@endcond
/// Delete \p key from the map
/**\anchor cds_nonintrusive_EllenBinTreeMap_rcu_erase_val
- RCU \p synchronize method can be called. RCU should not be locked.
+ RCU \p synchronize() method can be called. RCU should not be locked.
Return \p true if \p key is found and deleted, \p false otherwise
*/
template <typename K, typename Less>
bool erase_with( K const& key, Less pred )
{
+ CDS_UNUSED( pred );
return base_class::erase_with( key, cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >());
}
template <typename K, typename Less, typename Func>
bool erase_with( K const& key, Less pred, Func f )
{
+ CDS_UNUSED( pred );
return base_class::erase_with( key, cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >(),
[&f]( leaf_node& node) { f( node.m_Value ); } );
}
/// Extracts an item with minimal key from the map
/**
- If the map is not empty, the function returns \p true, \p result contains a pointer to value.
- If the map is empty, the function returns \p false, \p result is left unchanged.
+ Returns \ref cds::urcu::exempt_ptr "exempt_ptr" pointer to the leftmost item.
+ If the set is empty, returns empty \p exempt_ptr.
@note Due the concurrent nature of the map, the function extracts <i>nearly</i> minimum key.
It means that the function gets leftmost leaf of the tree and tries to unlink it.
RCU \p synchronize method can be called. RCU should NOT be locked.
The function does not free the item.
- The deallocator will be implicitly invoked when \p result object is destroyed or when
- <tt>result.release()</tt> is called, see cds::urcu::exempt_ptr for explanation.
- @note Before reusing \p result object you should call its \p release() method.
+ The deallocator will be implicitly invoked when the returned object is destroyed or when
+ its \p release() member function is called.
*/
- bool extract_min( exempt_ptr& result )
+ exempt_ptr extract_min()
{
- return base_class::extract_min_( result );
+ return exempt_ptr( base_class::extract_min_());
}
/// Extracts an item with maximal key from the map
/**
- If the map is not empty, the function returns \p true, \p result contains a pointer to extracted item.
- If the map is empty, the function returns \p false, \p result is left unchanged.
+ Returns \ref cds::urcu::exempt_ptr "exempt_ptr" pointer to the rightmost item.
+ If the set is empty, returns empty \p exempt_ptr.
@note Due the concurrent nature of the map, the function extracts <i>nearly</i> maximal key.
It means that the function gets rightmost leaf of the tree and tries to unlink it.
RCU \p synchronize method can be called. RCU should NOT be locked.
The function does not free the item.
- The deallocator will be implicitly invoked when \p result object is destroyed or when
- <tt>result.release()</tt> is called, see cds::urcu::exempt_ptr for explanation.
+ The deallocator will be implicitly invoked when the returned object is destroyed or when
+ its \p release() is called.
@note Before reusing \p result object you should call its \p release() method.
*/
- bool extract_max( exempt_ptr& result )
+ exempt_ptr extract_max()
{
- return base_class::extract_max_( result );
+ return exempt_ptr( base_class::extract_max_());
}
/// Extracts an item from the map
/** \anchor cds_nonintrusive_EllenBinTreeMap_rcu_extract
The function searches an item with key equal to \p key in the tree,
- unlinks it, and returns pointer to an item found in \p result parameter.
- If \p key is not found the function returns \p false.
+ unlinks it, and returns \ref cds::urcu::exempt_ptr "exempt_ptr" pointer to an item found.
+ If \p key is not found the function returns an empty \p exempt_ptr.
RCU \p synchronize method can be called. RCU should NOT be locked.
The function does not destroy the item found.
- The dealloctor will be implicitly invoked when \p result object is destroyed or when
- <tt>result.release()</tt> is called, see cds::urcu::exempt_ptr for explanation.
- @note Before reusing \p result object you should call its \p release() method.
+ The dealloctor will be implicitly invoked when the returned object is destroyed or when
+ its \p release() member function is called.
*/
template <typename Q>
- bool extract( exempt_ptr& result, Q const& key )
+ exempt_ptr extract( Q const& key )
{
- return base_class::extract_( result, key, typename base_class::node_compare());
+ return exempt_ptr( base_class::extract_( key, typename base_class::node_compare()));
}
/// Extracts an item from the map using \p pred for searching
/**
- The function is an analog of \ref cds_nonintrusive_EllenBinTreeMap_rcu_extract "extract(exempt_ptr&, Q const&)"
+ The function is an analog of \p extract(Q const&)
but \p pred is used for key compare.
\p Less has the interface like \p std::less and should meet \ref cds_container_EllenBinTreeSet_rcu_less
"predicate requirements".
\p pred must imply the same element order as the comparator used for building the map.
*/
template <typename Q, typename Less>
- bool extract_with( exempt_ptr& result, Q const& val, Less pred )
+ exempt_ptr extract_with( Q const& key, Less pred )
{
- return base_class::extract_with_( result, val,
- cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >() );
+ CDS_UNUSED( pred );
+ return exempt_ptr( base_class::extract_with_( key,
+ cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >() ));
}
/// Find the key \p key
template <typename K, typename Less, typename Func>
bool find_with( K const& key, Less pred, Func f )
{
+ CDS_UNUSED( pred );
return base_class::find_with( key, cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >(),
[&f](leaf_node& item, K const& ) { f( item.m_Value );});
}
- /// Find the key \p key
- /** \anchor cds_nonintrusive_EllenBinTreeMap_rcu_find_val
-
+ /// Checks whether the map contains \p key
+ /**
The function searches the item with key equal to \p key
and returns \p true if it is found, and \p false otherwise.
The function applies RCU lock internally.
*/
template <typename K>
+ bool contains( K const& key )
+ {
+ return base_class::contains( key );
+ }
+ //@cond
+ template <typename K>
+ CDS_DEPRECATED("deprecated, use contains()")
bool find( K const& key )
{
- return base_class::find( key );
+ return contains( key );
}
+ //@endcond
- /// Finds the key \p val using \p pred predicate for searching
+ /// Checks whether the map contains \p key using \p pred predicate for searching
/**
- The function is an analog of \ref cds_nonintrusive_EllenBinTreeMap_rcu_find_val "find(K const&)"
- but \p pred is used for key comparing.
- \p Less functor has the interface like \p std::less.
- \p Less must imply the same element order as the comparator used for building the map.
+ The function is similar to <tt>contains( key )</tt> but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less and should meet \ref cds_intrusive_EllenBinTree_rcu_less
+ "Predicate requirements".
+ \p Less must imply the same element order as the comparator used for building the set.
*/
template <typename K, typename Less>
+ bool contains( K const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return base_class::contains( key, cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >() );
+ }
+ //@cond
+ template <typename K, typename Less>
+ CDS_DEPRECATED("deprecated, use contains()")
bool find_with( K const& key, Less pred )
{
- return base_class::find_with( key, cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >() );
+ return contains( key, pred );
}
+ //@endcond
/// Finds \p key and return the item found
/** \anchor cds_nonintrusive_EllenBinTreeMap_rcu_get
The function is an analog of \ref cds_nonintrusive_EllenBinTreeMap_rcu_get "get(Q const&)"
but \p pred is used for comparing the keys.
- \p Less functor has the semantics like \p std::less but should take arguments of type \ref value_type
+ \p Less functor has the semantics like \p std::less but should take arguments of type \p key_type
and \p Q in any order.
\p pred must imply the same element order as the comparator used for building the map.
*/
template <typename Q, typename Less>
value_type * get_with( Q const& key, Less pred ) const
{
+ CDS_UNUSED( pred );
leaf_node * pNode = base_class::get_with( key,
cds::details::predicate_wrapper< leaf_node, Less, typename maker::key_accessor >());
return pNode ? &pNode->m_Value : nullptr;
}
/// Checks if the map is empty
- /**
- Emptiness is checked by item counting: if item count is zero then the map is empty.
- */
bool empty() const
{
return base_class::empty();
}
/// Returns item count in the map
+ /**
+ Only leaf nodes containing user data are counted.
+
+ The value returned depends on item counter type provided by \p Traits template parameter.
+ If it is \p atomicity::empty_item_counter this function always returns 0.
+
+ The function is not suitable for checking the tree emptiness, use \p empty()
+ member function for this purpose.
+ */
size_t size() const
{
return base_class::size();
{
return base_class::check_consistency();
}
-
};
}} // namespace cds::container
-#endif //#ifndef __CDS_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
+#endif //#ifndef CDSLIB_CONTAINER_ELLEN_BINTREE_MAP_RCU_H
projects / libcds.git / blobdiff