Docfix, minor changes

[libcds.git] / cds / container / michael_map_rcu.h

diff --git a/cds/container/michael_map_rcu.h b/cds/container/michael_map_rcu.h
index 03ba520d3742f0291b5eb321a3bf814a2ecbca5f..d2e0f420a5cb0f40b54eb29175502e3b5b4f7b20 100644 (file)
--- a/cds/container/michael_map_rcu.h
+++ b/cds/container/michael_map_rcu.h
@@ -1,4 +1,32 @@
-//$$CDS-header$$
+/*
+    This file is a part of libcds - Concurrent Data Structures library
+
+    (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_MICHAEL_MAP_RCU_H
 #define CDSLIB_CONTAINER_MICHAEL_MAP_RCU_H
 
 #ifndef CDSLIB_CONTAINER_MICHAEL_MAP_RCU_H
 #define CDSLIB_CONTAINER_MICHAEL_MAP_RCU_H


@@ -55,95 +83,78 @@ namespace cds { namespace container {
     {
     public:
         typedef cds::urcu::gc< RCU > gc;   ///< RCU used as garbage collector
     {
     public:
         typedef cds::urcu::gc< RCU > gc;   ///< RCU used as garbage collector

-        typedef OrderedList bucket_type;   ///< type of ordered list used as a bucket implementation
+        typedef OrderedList ordered_list;   ///< type of ordered list used as a bucket implementation

         typedef Traits      traits;        ///< Map traits
 
         typedef Traits      traits;        ///< Map traits
 

-        typedef typename bucket_type::key_type          key_type        ;   ///< key type
-        typedef typename bucket_type::mapped_type       mapped_type     ;   ///< value type
-        typedef typename bucket_type::value_type        value_type      ;   ///< key/value pair stored in the list
-        typedef typename bucket_type::key_comparator    key_comparator  ;   ///< key comparison functor
+        typedef typename ordered_list::key_type          key_type;      ///< key type
+        typedef typename ordered_list::mapped_type       mapped_type;   ///< value type
+        typedef typename ordered_list::value_type        value_type;    ///< key/value pair stored in the list
+        typedef typename ordered_list::key_comparator    key_comparator;///< key comparison functor
+#ifdef CDS_DOXYGEN_INVOKED
+        typedef typename ordered_list::stat         stat;       ///< Internal statistics
+        typedef typename ordered_list::exempt_ptr   exempt_ptr; ///< pointer to extracted node
+        /// Type of \p get() member function return value
+        typedef typename ordered_list::raw_ptr      raw_ptr;
+        typedef typename ordered_list::rcu_lock     rcu_lock;   ///< RCU scoped lock
+#endif

 
         /// Hash functor for \ref key_type and all its derivatives that you use
         typedef typename cds::opt::v::hash_selector< typename traits::hash >::type   hash;
         typedef typename traits::item_counter  item_counter;   ///< Item counter type
 
         /// Hash functor for \ref key_type and all its derivatives that you use
         typedef typename cds::opt::v::hash_selector< typename traits::hash >::type   hash;
         typedef typename traits::item_counter  item_counter;   ///< Item counter type

+        typedef typename traits::allocator     allocator;    ///< Bucket table allocator

 
 

-        /// Bucket table allocator
-        typedef cds::details::Allocator< bucket_type, typename traits::allocator >  bucket_table_allocator;
-
-        typedef typename bucket_type::rcu_lock      rcu_lock;   ///< RCU scoped lock
-        typedef typename bucket_type::exempt_ptr    exempt_ptr; ///< pointer to extracted node

         /// Group of \p extract_xxx functions require external locking if underlying ordered list requires that
         /// Group of \p extract_xxx functions require external locking if underlying ordered list requires that

-        static CDS_CONSTEXPR const bool c_bExtractLockExternal = bucket_type::c_bExtractLockExternal;
-        /// Type of \p get() member function return value
-        typedef typename bucket_type::raw_ptr raw_ptr;
+        static CDS_CONSTEXPR const bool c_bExtractLockExternal = ordered_list::c_bExtractLockExternal;

 
 

-        //@cond
-        typedef cds::container::michael_map::implementation_tag implementation_tag;
-        //@endcond
+        // GC and OrderedList::gc must be the same
+        static_assert(std::is_same<gc, typename ordered_list::gc>::value, "GC and OrderedList::gc must be the same");
+
+        // atomicity::empty_item_counter is not allowed as a item counter
+        static_assert(!std::is_same<item_counter, cds::atomicity::empty_item_counter>::value,
+            "cds::atomicity::empty_item_counter is not allowed as a item counter");

 
     protected:
 
     protected:

-        item_counter    m_ItemCounter; ///< Item counter
-        hash            m_HashFunctor; ///< Hash functor
-        bucket_type *   m_Buckets;     ///< bucket table
+        //@cond
+        typedef typename ordered_list::template select_stat_wrapper< typename ordered_list::stat > bucket_stat;

 
 

-    private:
+        typedef typename ordered_list::template rebind_traits<
+            cds::opt::item_counter< cds::atomicity::empty_item_counter >
+            , cds::opt::stat< typename bucket_stat::wrapped_stat >
+        >::type internal_bucket_type;
+
+        /// Bucket table allocator
+        typedef typename allocator::template rebind< internal_bucket_type >::other bucket_table_allocator;
+        //@endcond
+
+    public:

         //@cond
         //@cond

-        const size_t    m_nHashBitmask;
+        typedef typename bucket_stat::stat stat;
+        typedef typename internal_bucket_type::exempt_ptr   exempt_ptr;
+        typedef typename internal_bucket_type::raw_ptr      raw_ptr;
+        typedef typename internal_bucket_type::rcu_lock     rcu_lock;

         //@endcond
 
     protected:
         //@cond
         //@endcond
 
     protected:
         //@cond

-        /// Calculates hash value of \p key
-        template <typename Q>
-        size_t hash_value( Q const& key ) const
-        {
-            return m_HashFunctor( key ) & m_nHashBitmask;
-        }
-
-        /// Returns the bucket (ordered list) for \p key
-        template <typename Q>
-        bucket_type&    bucket( Q const& key )
-        {
-            return m_Buckets[ hash_value( key ) ];
-        }
-        template <typename Q>
-        bucket_type const&    bucket( Q const& key ) const
-        {
-            return m_Buckets[ hash_value( key ) ];
-        }
+        const size_t    m_nHashBitmask;
+        item_counter    m_ItemCounter; ///< Item counter
+        hash            m_HashFunctor; ///< Hash functor
+        internal_bucket_type *  m_Buckets;  ///< bucket table
+        stat            m_Stat; ///< Internal statistics

         //@endcond
         //@endcond

-    protected:
-        /// Forward iterator
-        /**
-            \p IsConst - constness boolean flag
-
-            The forward iterator for Michael's map is based on \p OrderedList forward iterator and has the following features:
-            - it has no post-increment operator, only pre-increment
-            - it iterates items in unordered fashion
-            - The iterator cannot be moved across thread boundary since it may contain GC's guard that is thread-private GC data.
-            - Iterator ensures thread-safety even if you delete the item that iterator points to. However, in case of concurrent
-              deleting operations it is no guarantee that you iterate all item in the map.

 
 

-            Therefore, the use of iterators in concurrent environment is not good idea. Use the iterator for the concurrent container
-            for debug purpose only.
-        */
+    protected:
+        //@cond

         template <bool IsConst>
         template <bool IsConst>

-        class iterator_type: private cds::intrusive::michael_set::details::iterator< bucket_type, IsConst >
+        class iterator_type: private cds::intrusive::michael_set::details::iterator< internal_bucket_type, IsConst >

         {
         {

-            //@cond
-            typedef cds::intrusive::michael_set::details::iterator< bucket_type, IsConst >  base_class;
+            typedef cds::intrusive::michael_set::details::iterator< internal_bucket_type, IsConst >  base_class;

             friend class MichaelHashMap;
             friend class MichaelHashMap;

-            //@endcond

 
         protected:
 
         protected:

-            //@cond
-            //typedef typename base_class::bucket_type    bucket_type;

             typedef typename base_class::bucket_ptr     bucket_ptr;
             typedef typename base_class::list_iterator  list_iterator;
 
             typedef typename base_class::bucket_ptr     bucket_ptr;
             typedef typename base_class::list_iterator  list_iterator;
 

-            //typedef typename bucket_type::key_type      key_type;
-            //@endcond
-

         public:
             /// Value pointer type (const for const_iterator)
             typedef typename cds::details::make_const_type<typename MichaelHashMap::mapped_type, IsConst>::pointer   value_ptr;
         public:
             /// Value pointer type (const for const_iterator)
             typedef typename cds::details::make_const_type<typename MichaelHashMap::mapped_type, IsConst>::pointer   value_ptr;


@@ -156,11 +167,9 @@ namespace cds { namespace container {
             typedef typename cds::details::make_const_type<typename MichaelHashMap::value_type, IsConst>::reference pair_ref;
 
         protected:
             typedef typename cds::details::make_const_type<typename MichaelHashMap::value_type, IsConst>::reference pair_ref;
 
         protected:

-            //@cond

             iterator_type( list_iterator const& it, bucket_ptr pFirst, bucket_ptr pLast )
                 : base_class( it, pFirst, pLast )
             {}
             iterator_type( list_iterator const& it, bucket_ptr pFirst, bucket_ptr pLast )
                 : base_class( it, pFirst, pLast )
             {}

-            //@endcond

 
         public:
             /// Default ctor
 
         public:
             /// Default ctor


@@ -220,9 +229,49 @@ namespace cds { namespace container {
                 return !( *this == i );
             }
         };
                 return !( *this == i );
             }
         };

+        //@endcond

 
     public:
 
     public:

+    ///@name Forward iterators (thread-safe under RCU lock)
+    //@{
+

         /// Forward iterator
         /// Forward iterator

+        /**
+            The forward iterator for Michael's map is based on \p OrderedList forward iterator and has some features:
+            - it has no post-increment operator
+            - it iterates items in unordered fashion
+
+            You may safely use iterators in multi-threaded environment only under RCU lock.
+            Otherwise, a crash is possible if another thread deletes the element the iterator points to.
+
+            The iterator interface:
+            \code
+            class iterator {
+            public:
+                // Default constructor
+                iterator();
+
+                // Copy construtor
+                iterator( iterator const& src );
+
+                // Dereference operator
+                value_type * operator ->() const;
+
+                // Dereference operator
+                value_type& operator *() const;
+
+                // Preincrement operator
+                iterator& operator ++();
+
+                // Assignment operator
+                iterator& operator = (iterator const& src);
+
+                // Equality operators
+                bool operator ==(iterator const& i ) const;
+                bool operator !=(iterator const& i ) const;
+            };
+            \endcode
+        */

         typedef iterator_type< false >    iterator;
 
         /// Const forward iterator
         typedef iterator_type< false >    iterator;
 
         /// Const forward iterator


@@ -249,40 +298,29 @@ namespace cds { namespace container {
         }
 
         /// Returns a forward const iterator addressing the first element in a map
         }
 
         /// Returns a forward const iterator addressing the first element in a map

-        //@{

         const_iterator begin() const
         {
             return get_const_begin();
         }
         const_iterator begin() const
         {
             return get_const_begin();
         }

+
+        /// Returns a forward const iterator addressing the first element in a map

         const_iterator cbegin() const
         {
             return get_const_begin();
         }
         const_iterator cbegin() const
         {
             return get_const_begin();
         }

-        //@}

 
         /// Returns an const iterator that addresses the location succeeding the last element in a map
 
         /// Returns an const iterator that addresses the location succeeding the last element in a map

-        //@{

         const_iterator end() const
         {
             return get_const_end();
         }
         const_iterator end() const
         {
             return get_const_end();
         }

+
+        /// Returns an const iterator that addresses the location succeeding the last element in a map

         const_iterator cend() const
         {
             return get_const_end();
         }
         const_iterator cend() const
         {
             return get_const_end();
         }

-        //@}
-
-    private:
-        //@cond
-        const_iterator get_const_begin() const
-        {
-            return const_iterator( const_cast<bucket_type const&>(m_Buckets[0]).begin(), m_Buckets, m_Buckets + bucket_count() );
-        }
-        const_iterator get_const_end() const
-        {
-            return const_iterator( const_cast<bucket_type const&>(m_Buckets[bucket_count() - 1]).end(), m_Buckets + bucket_count() - 1, m_Buckets + bucket_count() );
-        }
-        //@endcond
+    //@}

 
     public:
         /// Initializes the map
 
     public:
         /// Initializes the map


@@ -299,22 +337,19 @@ namespace cds { namespace container {
             size_t nMaxItemCount,   ///< estimation of max item count in the hash map
             size_t nLoadFactor      ///< load factor: estimation of max number of items in the bucket
         ) : m_nHashBitmask( michael_map::details::init_hash_bitmask( nMaxItemCount, nLoadFactor ))
             size_t nMaxItemCount,   ///< estimation of max item count in the hash map
             size_t nLoadFactor      ///< load factor: estimation of max number of items in the bucket
         ) : m_nHashBitmask( michael_map::details::init_hash_bitmask( nMaxItemCount, nLoadFactor ))

+          , m_Buckets( bucket_table_allocator().allocate( bucket_count()))

         {
         {

-            // GC and OrderedList::gc must be the same
-            static_assert( std::is_same<gc, typename bucket_type::gc>::value, "GC and OrderedList::gc must be the same");
-
-            // atomicity::empty_item_counter is not allowed as a item counter
-            static_assert( !std::is_same<item_counter, cds::atomicity::empty_item_counter>::value,
-                           "cds::atomicity::empty_item_counter is not allowed as a item counter");
-
-            m_Buckets = bucket_table_allocator().NewArray( bucket_count() );
+            for ( auto it = m_Buckets, itEnd = m_Buckets + bucket_count(); it != itEnd; ++it )
+                construct_bucket<bucket_stat>( it );

         }
 
         /// Clears hash map and destroys it
         ~MichaelHashMap()
         {
             clear();
         }
 
         /// Clears hash map and destroys it
         ~MichaelHashMap()
         {
             clear();

-            bucket_table_allocator().Delete( m_Buckets, bucket_count() );
+            for ( auto it = m_Buckets, itEnd = m_Buckets + bucket_count(); it != itEnd; ++it )
+                it->~internal_bucket_type();
+            bucket_table_allocator().deallocate( m_Buckets, bucket_count() );

         }
 
         /// Inserts new node with key and default value
         }
 
         /// Inserts new node with key and default value


@@ -426,7 +461,7 @@ namespace cds { namespace container {
 
             The function applies RCU lock internally.
 
 
             The function applies RCU lock internally.
 

-            Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
+            Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successful,

             \p second is true if new item has been added or \p false if the item with \p key
             already exists.
 
             \p second is true if new item has been added or \p false if the item with \p key
             already exists.
 


@@ -437,20 +472,17 @@ namespace cds { namespace container {
         template <typename K, typename Func>
         std::pair<bool, bool> update( K const& key, Func func, bool bAllowInsert = true )
         {
         template <typename K, typename Func>
         std::pair<bool, bool> update( K const& key, Func func, bool bAllowInsert = true )
         {

-            std::pair<bool, bool> bRet = bucket( key ).update( key, func );
-            if ( bRet.first && bRet.second )
+            std::pair<bool, bool> bRet = bucket( key ).update( key, func, bAllowInsert );
+            if ( bRet.second )

                 ++m_ItemCounter;
             return bRet;
         }
         //@cond
                 ++m_ItemCounter;
             return bRet;
         }
         //@cond

-        // Deprecated

         template <typename K, typename Func>
         template <typename K, typename Func>

+        CDS_DEPRECATED("ensure() is deprecated, use update()")

         std::pair<bool, bool> ensure( K const& key, Func func )
         {
         std::pair<bool, bool> ensure( K const& key, Func func )
         {

-            std::pair<bool, bool> bRet = bucket( key ).ensure( key, func );
-            if ( bRet.first && bRet.second )
-                ++m_ItemCounter;
-            return bRet;
+            return update( key, func, true );

         }
         //@endcond
 
         }
         //@endcond
 


@@ -550,7 +582,7 @@ namespace cds { namespace container {
             If the item is not found the function return an empty \p exempt_ptr.
 
             The function just excludes the key from the map and returns a pointer to item found.
             If the item is not found the function return an empty \p exempt_ptr.
 
             The function just excludes the key from the map and returns a pointer to item found.

-            Depends on \p bucket_type you should or should not lock RCU before calling of this function:
+            Depends on \p ordered_list you should or should not lock RCU before calling of this function:

             - for the set based on \ref cds_nonintrusive_MichaelList_rcu "MichaelList" RCU should not be locked
             - for the set based on \ref cds_nonintrusive_LazyList_rcu "LazyList" RCU should be locked
             See ordered list implementation for details.
             - for the set based on \ref cds_nonintrusive_MichaelList_rcu "MichaelList" RCU should not be locked
             - for the set based on \ref cds_nonintrusive_LazyList_rcu "LazyList" RCU should be locked
             See ordered list implementation for details.


@@ -660,8 +692,8 @@ namespace cds { namespace container {
             return bucket( key ).contains( key );
         }
         //@cond
             return bucket( key ).contains( key );
         }
         //@cond

-        // Deprecated

         template <typename K>
         template <typename K>

+        CDS_DEPRECATED("deprecated, use contains()")

         bool find( K const& key )
         {
             return bucket( key ).contains( key );
         bool find( K const& key )
         {
             return bucket( key ).contains( key );


@@ -680,8 +712,8 @@ namespace cds { namespace container {
             return bucket( key ).contains( key, pred );
         }
         //@cond
             return bucket( key ).contains( key, pred );
         }
         //@cond

-        // Deprecated

         template <typename K, typename Less>
         template <typename K, typename Less>

+        CDS_DEPRECATED("deprecated, use contains()")

         bool find_with( K const& key, Less pred )
         {
             return bucket( key ).contains( key, pred );
         bool find_with( K const& key, Less pred )
         {
             return bucket( key ).contains( key, pred );


@@ -692,7 +724,7 @@ namespace cds { namespace container {
         /** \anchor cds_nonintrusive_MichaelHashMap_rcu_get
             The function searches the item with key equal to \p key and returns the pointer to item found.
             If \p key is not found it returns \p nullptr.
         /** \anchor cds_nonintrusive_MichaelHashMap_rcu_get
             The function searches the item with key equal to \p key and returns the pointer to item found.
             If \p key is not found it returns \p nullptr.

-            Note the type of returned value depends on underlying \p bucket_type.
+            Note the type of returned value depends on underlying \p ordered_list.

             For details, see documentation of ordered list you use.
 
             Note the compare functor should accept a parameter of type \p K that can be not the same as \p key_type.
             For details, see documentation of ordered list you use.
 
             Note the compare functor should accept a parameter of type \p K that can be not the same as \p key_type.


@@ -773,6 +805,12 @@ namespace cds { namespace container {
             return m_ItemCounter;
         }
 
             return m_ItemCounter;
         }
 

+        /// Returns const reference to internal statistics
+        stat const& statistics() const
+        {
+            return m_Stat;
+        }
+

         /// Returns the size of hash table
         /**
             Since \p %MichaelHashMap cannot dynamically extend the hash table size,
         /// Returns the size of hash table
         /**
             Since \p %MichaelHashMap cannot dynamically extend the hash table size,


@@ -783,6 +821,51 @@ namespace cds { namespace container {
         {
             return m_nHashBitmask + 1;
         }
         {
             return m_nHashBitmask + 1;
         }

+
+    protected:
+        //@cond
+        /// Calculates hash value of \p key
+        template <typename Q>
+        size_t hash_value( Q const& key ) const
+        {
+            return m_HashFunctor( key ) & m_nHashBitmask;
+        }
+
+        /// Returns the bucket (ordered list) for \p key
+        template <typename Q>
+        internal_bucket_type&    bucket( Q const& key )
+        {
+            return m_Buckets[hash_value( key )];
+        }
+        template <typename Q>
+        internal_bucket_type const&    bucket( Q const& key ) const
+        {
+            return m_Buckets[hash_value( key )];
+        }
+        //@endcond
+    private:
+        //@cond
+        const_iterator get_const_begin() const
+        {
+            return const_iterator( const_cast<internal_bucket_type const&>(m_Buckets[0]).begin(), m_Buckets, m_Buckets + bucket_count() );
+        }
+        const_iterator get_const_end() const
+        {
+            return const_iterator( const_cast<internal_bucket_type const&>(m_Buckets[bucket_count() - 1]).end(), m_Buckets + bucket_count() - 1, m_Buckets + bucket_count() );
+        }
+
+        template <typename Stat>
+        typename std::enable_if< Stat::empty >::type construct_bucket( internal_bucket_type* bucket )
+        {
+            new (bucket) internal_bucket_type;
+        }
+
+        template <typename Stat>
+        typename std::enable_if< !Stat::empty >::type construct_bucket( internal_bucket_type* bucket )
+        {
+            new (bucket) internal_bucket_type( m_Stat );
+        }
+        //@endcond

     };
 }}  // namespace cds::container
 
     };
 }}  // namespace cds::container