Added internal statistics to MichaelSet/Map

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

diff --git a/cds/container/michael_map.h b/cds/container/michael_map.h
index 1adc0be8f3dfc5f67166ae2e3925aae3abc6e93b..f0cd85975d051b3d4200844c1fa5e79c5f716dae 100644 (file)
--- a/cds/container/michael_map.h
+++ b/cds/container/michael_map.h
@@ -25,13 +25,14 @@
     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
     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.     
+    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */
 
 #ifndef CDSLIB_CONTAINER_MICHAEL_MAP_H
 #define CDSLIB_CONTAINER_MICHAEL_MAP_H
 
 #include <cds/container/details/michael_map_base.h>
 */
 
 #ifndef CDSLIB_CONTAINER_MICHAEL_MAP_H
 #define CDSLIB_CONTAINER_MICHAEL_MAP_H
 
 #include <cds/container/details/michael_map_base.h>

+#include <cds/container/details/iterable_list_base.h>

 #include <cds/details/allocator.h>
 
 namespace cds { namespace container {
 #include <cds/details/allocator.h>
 
 namespace cds { namespace container {


@@ -52,10 +53,10 @@ namespace cds { namespace container {
         - \p GC - Garbage collector used. You may use any \ref cds_garbage_collector "Garbage collector"
             from the \p libcds library.
             Note the \p GC must be the same as the GC used for \p OrderedList
         - \p GC - Garbage collector used. You may use any \ref cds_garbage_collector "Garbage collector"
             from the \p libcds library.
             Note the \p GC must be the same as the GC used for \p OrderedList

-        - \p OrderedList - ordered key-value list implementation used as bucket for hash map, for example, \p MichaelKVList
-            or \p LazyKVList. The ordered list implementation specifies the \p Key and \p Value types stored in the hash-map,
-            the reclamation schema \p GC used by hash-map, the comparison functor for the type \p Key and other features
-            specific for the ordered list.
+        - \p OrderedList - ordered key-value list implementation used as bucket for hash map, for example, \p MichaelKVList,
+            \p LazyKVList, \p IterableKVList. The ordered list implementation specifies the \p Key and \p Value types
+            stored in the hash-map, the reclamation schema \p GC used by hash-map, the comparison functor for the type \p Key
+            and other features specific for the ordered list.

         - \p Traits - map traits, default is \p michael_map::traits.
             Instead of defining \p Traits struct you may use option-based syntax with \p michael_map::make_traits metafunction.
 
         - \p Traits - map traits, default is \p michael_map::traits.
             Instead of defining \p Traits struct you may use option-based syntax with \p michael_map::make_traits metafunction.
 


@@ -147,60 +148,64 @@ namespace cds { namespace container {
     class MichaelHashMap
     {
     public:
     class MichaelHashMap
     {
     public:

-        typedef GC          gc;          ///< Garbage collector
-        typedef OrderedList bucket_type; ///< type of ordered list to be used as a bucket
-        typedef Traits      traits;      ///< Map traits
+        typedef GC          gc;             ///< Garbage collector
+        typedef OrderedList ordered_list;   ///< type of ordered list to be used as a bucket
+        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 map
+        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 map
+        typedef typename traits::allocator         allocator;   ///< Bucket table allocator

 
 

-        typedef typename bucket_type::key_comparator key_comparator;  ///< key compare functor
+        typedef typename ordered_list::key_comparator key_comparator;  ///< key compare functor
+#ifdef CDS_DOXYGEN_INVOKED
+        typedef typename ordered_list::stat           stat;           ///< Internal statistics
+        /// Guarded pointer - a result of \p get() and \p extract() functions
+        typedef typename ordered_list::guarded_ptr    guarded_ptr;
+#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
 

-        /// Bucket table allocator
-        typedef cds::details::Allocator< bucket_type, typename traits::allocator >  bucket_table_allocator;
-        typedef typename bucket_type::guarded_ptr  guarded_ptr; ///< Guarded pointer
+        // 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");

 
 

-        static CDS_CONSTEXPR const size_t c_nHazardPtrCount = bucket_type::c_nHazardPtrCount; ///< Count of hazard pointer required
+        // atomicity::empty_item_counter is not allowed as a item counter
+        static_assert( !std::is_same<item_counter, atomicity::empty_item_counter>::value,
+                        "atomicity::empty_item_counter is not allowed as a item counter");

 
 

-    protected:
-        item_counter    m_ItemCounter; ///< Item counter
-        hash            m_HashFunctor; ///< Hash functor
-        bucket_type *   m_Buckets;     ///< bucket table
+        static CDS_CONSTEXPR const size_t c_nHazardPtrCount = ordered_list::c_nHazardPtrCount; ///< Count of hazard pointer required

 
 

-    private:

         //@cond
         //@cond

-        const size_t    m_nHashBitmask;
+        typedef typename ordered_list::template select_stat_wrapper< typename ordered_list::stat > bucket_stat;
+
+        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;
+
+        typedef typename internal_bucket_type::guarded_ptr guarded_ptr;
+        typedef typename allocator::template rebind< internal_bucket_type >::other bucket_table_allocator;
+        typedef typename bucket_stat::stat stat;

         //@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 ) ];
-        }
+        const size_t            m_nHashBitmask;
+        internal_bucket_type*   m_Buckets;     ///< bucket table
+        item_counter            m_ItemCounter; ///< Item counter
+        hash                    m_HashFunctor; ///< Hash functor
+        stat                    m_Stat;        ///< Internal statistics

         //@endcond
 
     protected:
         //@cond
         /// Forward iterator
         template <bool IsConst>
         //@endcond
 
     protected:
         //@cond
         /// Forward iterator
         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 >

         {
         {

-            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;
 
         protected:
             friend class MichaelHashMap;
 
         protected:


@@ -288,44 +293,50 @@ namespace cds { namespace container {
     //@{
         /// Forward iterator
         /**
     //@{
         /// Forward iterator
         /**

-            The iteration is unordered.
-            The iterator object is thread-safe: the element pointed by the iterator object is guarded,
-            so, the element cannot be reclaimed while the iterator object is alive.
-            However, passing an iterator object between threads is dangerous.
-
-            @warning Due to concurrent nature of Michael's map it is not guarantee that you can iterate
-            all elements in the map: any concurrent deletion can exclude the element
-            pointed by the iterator from the map, and your iteration can be terminated
-            before end of the map. Therefore, such iteration is more suitable for debugging purpose only.
-
-            Remember, each iterator object requires an additional hazard pointer, that may be
-            a limited resource for \p GC like \p gc::HP (for \p gc::DHP the count of
-            guards is unlimited).
-
-            The iterator class supports the following minimalistic interface:
+            The forward iterator for Michael's map has some features:
+            - it has no post-increment operator
+            - to protect the value, the iterator contains a GC-specific guard + another guard is required locally for increment operator.
+              For some GC (like as \p gc::HP), a guard is a limited resource per thread, so an exception (or assertion) "no free guard"
+              may be thrown if the limit of guard count per thread is exceeded.
+            - The iterator cannot be moved across thread boundary because it contains thread-private GC's guard.
+
+            Iterator thread safety depends on type of \p OrderedList:
+            - for \p MichaelKVList and \p LazyKVList: iterator guarantees safety even if you delete the item that iterator points to
+              because that item is guarded by hazard pointer.
+              However, in case of concurrent deleting operations it is no guarantee that you iterate all item in the map.
+              Moreover, a crash is possible when you try to iterate the next element that has been deleted by concurrent thread.
+              Use this iterator on the concurrent container for debugging purpose only.
+            - for \p IterableList: iterator is thread-safe. You may use it freely in concurrent environment.
+
+            The iterator interface:

             \code
             \code

-            struct iterator {
-                // Default ctor
+            class iterator {
+            public:
+                // Default constructor

                 iterator();
 
                 iterator();
 

-                // Copy ctor
-                iterator( iterator const& s);
+                // Copy construtor
+                iterator( iterator const& src );

 
 

+                // Dereference operator

                 value_type * operator ->() const;
                 value_type * operator ->() const;

+
+                // Dereference operator

                 value_type& operator *() const;
 
                 value_type& operator *() const;
 

-                // Pre-increment
+                // Preincrement operator

                 iterator& operator ++();
 
                 iterator& operator ++();
 

-                // Copy assignment
+                // Assignment operator

                 iterator& operator = (iterator const& src);
 
                 iterator& operator = (iterator const& src);
 

+                // Equality operators

                 bool operator ==(iterator const& i ) const;
                 bool operator !=(iterator const& i ) const;
             };
             \endcode
 
                 bool operator ==(iterator const& i ) const;
                 bool operator !=(iterator const& i ) const;
             };
             \endcode
 

-            Note, the iterator object returned by \p end(), \p cend() member functions points to \p nullptr and should not be dereferenced.
+            @note The iterator object returned by \p end(), \p cend() member functions points to \p nullptr and should not be dereferenced.

         */
         typedef iterator_type< false >    iterator;
 
         */
         typedef iterator_type< false >    iterator;
 


@@ -338,7 +349,7 @@ namespace cds { namespace container {
         */
         iterator begin()
         {
         */
         iterator begin()
         {

-            return iterator( m_Buckets[0].begin(), m_Buckets, m_Buckets + bucket_count() );
+            return iterator( bucket_begin()->begin(), bucket_begin(), bucket_end() );

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


@@ -349,7 +360,7 @@ namespace cds { namespace container {
         */
         iterator end()
         {
         */
         iterator end()
         {

-            return iterator( m_Buckets[bucket_count() - 1].end(), m_Buckets + bucket_count() - 1, m_Buckets + bucket_count() );
+            return iterator( bucket_end()[-1].end(), bucket_end() - 1, bucket_end() );

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


@@ -375,18 +386,6 @@ namespace cds { namespace container {
         }
     //@}
 
         }
     //@}
 

-    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
         /** @anchor cds_nonintrusive_MichaelHashMap_hp_ctor
     public:
         /// Initializes the map
         /** @anchor cds_nonintrusive_MichaelHashMap_hp_ctor


@@ -401,23 +400,22 @@ namespace cds { namespace container {
         MichaelHashMap(
             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
         MichaelHashMap(
             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_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, atomicity::empty_item_counter>::value,
-                           "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


@@ -432,9 +430,9 @@ namespace cds { namespace container {
             Returns \p true if inserting successful, \p false otherwise.
         */
         template <typename K>
             Returns \p true if inserting successful, \p false otherwise.
         */
         template <typename K>

-        bool insert( const K& key )
+        bool insert( K&& key )

         {
         {

-            const bool bRet = bucket( key ).insert( key );
+            const bool bRet = bucket( key ).insert( std::forward<K>( key ));

             if ( bRet )
                 ++m_ItemCounter;
             return bRet;
             if ( bRet )
                 ++m_ItemCounter;
             return bRet;


@@ -452,9 +450,9 @@ namespace cds { namespace container {
             Returns \p true if \p val is inserted into the map, \p false otherwise.
         */
         template <typename K, typename V>
             Returns \p true if \p val is inserted into the map, \p false otherwise.
         */
         template <typename K, typename V>

-        bool insert( K const& key, V const& val )
+        bool insert( K&& key, V&& val )

         {
         {

-            const bool bRet = bucket( key ).insert( key, val );
+            const bool bRet = bucket( key ).insert( std::forward<K>( key ), std::forward<V>( val ));

             if ( bRet )
                 ++m_ItemCounter;
             return bRet;
             if ( bRet )
                 ++m_ItemCounter;
             return bRet;


@@ -492,9 +490,9 @@ namespace cds { namespace container {
             synchronization.
         */
         template <typename K, typename Func>
             synchronization.
         */
         template <typename K, typename Func>

-        bool insert_with( const K& key, Func func )
+        bool insert_with( K&& key, Func func )

         {
         {

-            const bool bRet = bucket( key ).insert_with( key, func );
+            const bool bRet = bucket( key ).insert_with( std::forward<K>( key ), func );

             if ( bRet )
                 ++m_ItemCounter;
             return bRet;
             if ( bRet )
                 ++m_ItemCounter;
             return bRet;


@@ -509,7 +507,9 @@ namespace cds { namespace container {
             (note that in this case the \ref key_type should be constructible from type \p K).
             Otherwise, if \p key is found, the functor \p func is called with item found.
 
             (note that in this case the \ref key_type should be constructible from type \p K).
             Otherwise, if \p key is found, the functor \p func is called with item found.
 

-            The functor \p Func signature is:
+            The functor \p func signature depends of \p OrderedList:
+
+            <b>for \p MichaelKVList, \p LazyKVList</b>

             \code
                 struct my_functor {
                     void operator()( bool bNew, value_type& item );
             \code
                 struct my_functor {
                     void operator()( bool bNew, value_type& item );


@@ -521,18 +521,30 @@ namespace cds { namespace container {
 
             The functor may change any fields of the \p item.second that is \p mapped_type.
 
 
             The functor may change any fields of the \p item.second that is \p mapped_type.
 

-            Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
+            <b>for \p IterableKVList</b>
+            \code
+                void func( value_type& val, value_type * old );
+            \endcode
+            where
+            - \p val - a new data constructed from \p key
+            - \p old - old value that will be retired. If new item has been inserted then \p old is \p nullptr.
+
+            The functor may change non-key fields of \p val; however, \p func must guarantee
+            that during changing no any other modifications could be made on this item by concurrent threads.
+
+            @return <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.
 

-            @warning For \ref cds_nonintrusive_MichaelKVList_gc "MichaelKVList" as the bucket see \ref cds_intrusive_item_creating "insert item troubleshooting".
+            @warning For \ref cds_nonintrusive_MichaelKVList_gc "MichaelKVList" and \ref cds_nonintrusive_IterableKVList_gc "IterableKVList" 
+            as the bucket see \ref cds_intrusive_item_creating "insert item troubleshooting".

             \ref cds_nonintrusive_LazyKVList_gc "LazyKVList" provides exclusive access to inserted item and does not require any node-level
             synchronization.
         */
         template <typename K, typename Func >
             \ref cds_nonintrusive_LazyKVList_gc "LazyKVList" provides exclusive access to inserted item and does not require any node-level
             synchronization.
         */
         template <typename K, typename Func >

-        std::pair<bool, bool> update( K const& key, Func func, bool bAllowInsert = true )
+        std::pair<bool, bool> update( K&& key, Func func, bool bAllowInsert = true )

         {
         {

-            std::pair<bool, bool> bRet = bucket( key ).update( key, func, bAllowInsert );
+            std::pair<bool, bool> bRet = bucket( key ).update( std::forward<K>( key ), func, bAllowInsert );

             if ( bRet.first && bRet.second )
                 ++m_ItemCounter;
             return bRet;
             if ( bRet.first && bRet.second )
                 ++m_ItemCounter;
             return bRet;


@@ -549,6 +561,34 @@ namespace cds { namespace container {
         }
         //@endcond
 
         }
         //@endcond
 

+        /// Inserts or updates the node (only for \p IterableKVList)
+        /**
+            The operation performs inserting or changing data with lock-free manner.
+
+            If the item \p val is not found in the map, then \p val is inserted iff \p bAllowInsert is \p true.
+            Otherwise, the current element is changed to \p val, the old element will be retired later.
+
+            Returns std::pair<bool, bool> where \p first is \p true if operation is successful,
+            \p second is \p true if \p val has been added or \p false if the item with that key
+            already in the map.
+        */
+        template <typename Q, typename V>
+#ifdef CDS_DOXYGEN_INVOKED
+        std::pair<bool, bool>
+#else
+        typename std::enable_if< 
+            std::is_same< Q, Q>::value && is_iterable_list< ordered_list >::value,
+            std::pair<bool, bool>
+        >::type
+#endif
+        upsert( Q&& key, V&& val, bool bAllowInsert = true )
+        {
+            std::pair<bool, bool> bRet = bucket( val ).upsert( std::forward<Q>( key ), std::forward<V>( val ), bAllowInsert );
+            if ( bRet.second )
+                ++m_ItemCounter;
+            return bRet;
+        }
+

         /// For key \p key inserts data of type \p mapped_type created from \p args
         /**
             \p key_type should be constructible from type \p K
         /// For key \p key inserts data of type \p mapped_type created from \p args
         /**
             \p key_type should be constructible from type \p K


@@ -845,6 +885,63 @@ namespace cds { namespace container {
         {
             return m_nHashBitmask + 1;
         }
         {
             return m_nHashBitmask + 1;
         }

+
+        /// Returns const reference to internal statistics
+        stat const& statistics() const
+        {
+            return m_Stat;
+        }
+
+    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 )];
+        }
+        //@endcond
+
+    private:
+        //@cond
+        internal_bucket_type* bucket_begin() const
+        {
+            return m_Buckets;
+        }
+
+        internal_bucket_type* bucket_end() const
+        {
+            return m_Buckets + bucket_count();
+        }
+
+        const_iterator get_const_begin() const
+        {
+            return const_iterator( bucket_begin()->cbegin(), bucket_begin(), bucket_end() );
+        }
+        const_iterator get_const_end() const
+        {
+            return const_iterator( (bucket_end() - 1)->cend(), bucket_end() - 1, bucket_end() );
+        }
+
+        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