cds  2.2.0
cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits > Class Template Reference

Split-ordered list set (template specialization for RCU) More...

#include <cds/container/split_list_set_rcu.h>

Inheritance diagram for cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >:
cds::intrusive::SplitListSet< cds::urcu::gc< RCU >, T, Traits::ordered_list, Traits >

Public Types

typedef cds::urcu::gc< RCU > gc
 RCU-based garbage collector.
 
typedef T value_type
 Type of value to be storedin the set.
 
typedef Traits traits
 Traits template argument
 
typedef maker::ordered_list ordered_list
 Underlying ordered list class.
 
typedef base_class::key_comparator key_comparator
 key compare functor
 
typedef base_class::hash hash
 Hash functor for value_type and all its derivatives that you use.
 
typedef base_class::item_counter item_counter
 Item counter type.
 
typedef base_class::stat stat
 Internal statistics.
 
typedef base_class::rcu_lock rcu_lock
 
using exempt_ptr = cds::urcu::exempt_ptr< gc, node_type, value_type, typename maker::ordered_list_traits::disposer >
 pointer to extracted node
 
typedef implementation_defined raw_ptr
 pointer to the node for get() function More...
 

Public Member Functions

 SplitListSet ()
 Initializes split-ordered list of default capacity. More...
 
 SplitListSet (size_t nItemCount, size_t nLoadFactor=1)
 Initializes split-ordered list. More...
 
template<typename Q >
bool insert (Q const &val)
 Inserts new node. More...
 
template<typename Q , typename Func >
bool insert (Q const &key, Func f)
 Inserts new node. More...
 
template<typename... Args>
bool emplace (Args &&... args)
 Inserts data of type value_type created from args. More...
 
template<typename Q , typename Func >
std::pair< bool, bool > update (Q const &val, Func func, bool bAllowInsert=true)
 Updates an element with given val. More...
 
template<typename Q >
bool erase (Q const &key)
 Deletes key from the set. More...
 
template<typename Q , typename Less >
bool erase_with (Q const &key, Less pred)
 Deletes the item from the set using pred predicate for searching. More...
 
template<typename Q , typename Func >
bool erase (Q const &key, Func f)
 Deletes key from the set. More...
 
template<typename Q , typename Less , typename Func >
bool erase_with (Q const &key, Less pred, Func f)
 Deletes the item from the set using pred predicate for searching. More...
 
template<typename Q >
exempt_ptr extract (Q const &key)
 Extracts an item from the set. More...
 
template<typename Q , typename Less >
exempt_ptr extract_with (Q const &key, Less pred)
 Extracts an item from the set using pred predicate for searching. More...
 
template<typename Q , typename Func >
bool find (Q &key, Func f)
 Finds the key key. More...
 
template<typename Q , typename Less , typename Func >
bool find_with (Q &key, Less pred, Func f)
 Finds the key key using pred predicate for searching. More...
 
template<typename Q >
bool contains (Q const &key)
 Checks whether the set contains key. More...
 
template<typename Q , typename Less >
bool contains (Q const &key, Less pred)
 Checks whether the map contains key using pred predicate for searching. More...
 
template<typename Q >
raw_ptr get (Q const &key)
 Finds the key key and return the item found. More...
 
template<typename Q , typename Less >
raw_ptr get_with (Q const &key, Less pred)
 Finds the key key and return the item found. More...
 
void clear ()
 Clears the set (not atomic)
 
bool empty () const
 Checks if the set is empty. More...
 
size_t size () const
 Returns item count in the set.
 
stat const & statistics () const
 Returns internal statistics.
 
ordered_list::stat const & list_statistics () const
 Returns internal statistics for ordered_list.
 

Static Public Attributes

static constexpr const bool c_bExtractLockExternal = base_class::c_bExtractLockExternal
 Group of extract_xxx functions require external locking if underlying ordered list requires that.
 

Forward iterators (thread-safe under RCU lock)

typedef iterator_type< false > iterator
 Forward iterator. More...
 
typedef iterator_type< true > const_iterator
 Forward const iterator.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a set. More...
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a set. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a set.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a set.
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 

Additional Inherited Members

- Protected Types inherited from cds::intrusive::SplitListSet< cds::urcu::gc< RCU >, T, Traits::ordered_list, Traits >
typedef cds::urcu::gc< RCU > gc
 Garbage collector.
 
typedef Traits traits
 Set traits.
 
typedef T ordered_list
 type of ordered list used as a base for split-list
 
typedef ordered_list::value_type value_type
 type of value stored in the split-list
 
typedef ordered_list::key_comparator key_comparator
 key comparison functor
 
typedef ordered_list::disposer disposer
 Node disposer functor.
 
typedef cds::opt::v::hash_selector< typename traits::hash >::type hash
 Hash functor for value_type and all its derivatives you use.
 
typedef traits::item_counter item_counter
 Item counter type.
 
typedef traits::back_off back_off
 back-off strategy for spinning
 
typedef traits::memory_model memory_model
 Memory ordering. See cds::opt::memory_model option.
 
typedef traits::stat stat
 Internal statistics, see spit_list::stat.
 
typedef ordered_list::guarded_ptr guarded_ptr
 Guarded pointer.
 
typedef iterator_type< false > iterator
 Forward iterator. More...
 
typedef iterator_type< true > const_iterator
 Const forward iterator. More...
 
- Protected Member Functions inherited from cds::intrusive::SplitListSet< cds::urcu::gc< RCU >, T, Traits::ordered_list, Traits >
 SplitListSet ()
 Initialize split-ordered list of default capacity. More...
 
 SplitListSet (size_t nItemCount, size_t nLoadFactor=1)
 Initialize split-ordered list. More...
 
 ~SplitListSet ()
 Destroys split-list set.
 
bool insert (value_type &val)
 Inserts new node. More...
 
bool insert (value_type &val, Func f)
 Inserts new node. More...
 
std::pair< bool, bool > update (value_type &val, Func func, bool bAllowInsert=true)
 Updates the node. More...
 
std::pair< bool, bool > upsert (value_type &val, bool bAllowInsert=true)
 Inserts or updates the node (only for IterableList) More...
 
bool unlink (value_type &val)
 Unlinks the item val from the set. More...
 
bool erase (Q const &key)
 Deletes the item from the set. More...
 
bool erase (Q const &key, Func f)
 Deletes the item from the set. More...
 
bool erase_with (const Q &key, Less pred)
 Deletes the item from the set with comparing functor pred. More...
 
bool erase_with (Q const &key, Less pred, Func f)
 Deletes the item from the set with comparing functor pred. More...
 
guarded_ptr extract (Q const &key)
 Extracts the item with specified key. More...
 
guarded_ptr extract_with (Q const &key, Less pred)
 Extracts the item using compare functor pred. More...
 
bool find (Q &key, Func f)
 Finds the key key. More...
 
iterator find (Q &key)
 Finds key and returns iterator pointed to the item found (only for IterableList) More...
 
bool find_with (Q &key, Less pred, Func f)
 Finds the key key with pred predicate for comparing. More...
 
iterator find_with (Q &key, Less pred)
 Finds key using pred predicate and returns iterator pointed to the item found (only for IterableList) More...
 
bool contains (Q const &key)
 Checks whether the set contains key. More...
 
bool contains (Q const &key, Less pred)
 Checks whether the set contains key using pred predicate for searching. More...
 
guarded_ptr get (Q const &key)
 Finds the key key and return the item found. More...
 
guarded_ptr get_with (Q const &key, Less pred)
 Finds the key key and return the item found. More...
 
size_t size () const
 Returns item count in the set.
 
bool empty () const
 Checks if the set is empty. More...
 
void clear ()
 Clears the set (non-atomic) More...
 
stat const & statistics () const
 Returns internal statistics.
 
T ::stat const & list_statistics () const
 Returns internal statistics for OrderedList.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a split-list. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a split-list.
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a split-list. More...
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a split-list.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a split-list.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a split-list.
 
- Static Protected Attributes inherited from cds::intrusive::SplitListSet< cds::urcu::gc< RCU >, T, Traits::ordered_list, Traits >
static constexpr const size_t c_nHazardPtrCount
 Count of hazard pointer required.
 

Detailed Description

template<class RCU, class T, class Traits = split_list::traits>
class cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >

Split-ordered list set (template specialization for RCU)

Hash table implementation based on split-ordered list algorithm discovered by Ori Shalev and Nir Shavit, see

  • [2003] Ori Shalev, Nir Shavit "Split-Ordered Lists - Lock-free Resizable Hash Tables"
  • [2008] Nir Shavit "The Art of Multiprocessor Programming"

See intrusive::SplitListSet for a brief description of the split-list algorithm.

Template parameters:

Iterators

The class supports a forward iterator (iterator and const_iterator). The iteration is unordered.

You may iterate over split-list set items only under RCU lock. Only in this case the iterator is thread-safe since while RCU is locked any set's item cannot be reclaimed.

Warning
The iterator object cannot be passed between threads
Due to concurrent nature of skip-list set it is not guarantee that you can iterate all elements in the set: any concurrent deletion can exclude the element pointed by the iterator from the set, and your iteration can be terminated before end of the set. Therefore, such iteration is more suitable for debugging purposes

The iterator class supports the following minimalistic interface:

struct iterator {
// Default ctor
// Copy ctor
iterator( iterator const& s);
value_type * operator ->() const;
value_type& operator *() const;
// Pre-increment
iterator& operator ++();
// Copy assignment
iterator& operator = (const iterator& src);
bool operator ==(iterator const& i ) const;
bool operator !=(iterator const& i ) const;
};

Note, the iterator object returned by end(), cend() member functions points to nullptr and should not be dereferenced.

Usage

You should decide what garbage collector you want, and what ordered list you want to use. Split-ordered list is an original data structure based on an ordered list. Suppose, you want construct split-list set based on cds::urcu::general_buffered<> GC and LazyList as ordered list implementation. So, you beginning your program with following include:

#include <cds/urcu/general_buffered.h>
#include <cds/container/lazy_list_rcu.h>
#include <cds/container/split_list_set_rcu.h>
namespace cc = cds::container;
// The data belonged to split-ordered list
sturuct foo {
int nKey; // key field
std::string strValue ; // value field
};

The inclusion order is important:

  • first, include one of RCU implementation (cds/urcu/general_buffered.h in our case)
  • second, include file for ordered-list implementation (for this example, cds/container/lazy_list_rcu.h),
  • then, the header for RCU-based split-list set cds/container/split_list_set_rcu.h.

Now, you should declare traits for split-list set. The main parts of traits are a hash functor for the set and a comparing functor for ordered list. Note that we define several function in foo_hash and foo_less functors for different argument types since we want call our SplitListSet object by the key of type int and by the value of type foo.

The second attention: instead of using LazyList in SplitListSet traits we use cds::contaner::lazy_list_tag tag for the lazy list. The split-list requires significant support from underlying ordered list class and it is not good idea to dive you into deep implementation details of split-list and ordered list interrelations. The tag paradigm simplifies split-list interface.

// foo hash functor
struct foo_hash {
size_t operator()( int key ) const { return std::hash( key ) ; }
size_t operator()( foo const& item ) const { return std::hash( item.nKey ) ; }
};
// foo comparator
struct foo_less {
bool operator()(int i, foo const& f ) const { return i < f.nKey ; }
bool operator()(foo const& f, int i ) const { return f.nKey < i ; }
bool operator()(foo const& f1, foo const& f2) const { return f1.nKey < f2.nKey; }
};
// SplitListSet traits
struct foo_set_traits: public cc::split_list::traits
{
typedef cc::lazy_list_tag ordered_list ; // what type of ordered list we want to use
typedef foo_hash hash ; // hash functor for our data stored in split-list set
// Type traits for our LazyList class
struct ordered_list_traits: public cc::lazy_list::traits
{
typedef foo_less less ; // use our foo_less as comparator to order list nodes
};
};

Now you are ready to declare our set class based on SplitListSet:

typedef cc::SplitListSet< cds::urcu::gc<cds::urcu::general_buffered<> >, foo, foo_set_traits > foo_set;

You may use the modern option-based declaration instead of classic type-traits-based one:

cds::urcu::gc<cds::urcu::general_buffered<> > // RCU type used
,foo // type of data stored
,cc::split_list::make_traits< // metafunction to build split-list traits
cc::split_list::ordered_list<cc::lazy_list_tag> // tag for underlying ordered list implementation
,cc::opt::hash< foo_hash > // hash functor
,cc::split_list::ordered_list_traits< // ordered list traits
cc::lazy_list::make_traits< // metafunction to build lazy list traits
cc::opt::less< foo_less > // less-based compare functor
>::type
>
>::type
> foo_set;

In case of option-based declaration using split_list::make_traits metafunction the struct foo_set_traits is not required.

Now, the set of type foo_set is ready to use in your program.

Note that in this example we show only mandatory traits parts, optional ones is the default and they are inherited from container::split_list::traits. There are many other options for deep tuning of the split-list and ordered-list containers.

Member Typedef Documentation

§ iterator

template<class RCU , class T , class Traits = split_list::traits>
typedef iterator_type<false> cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::iterator

Forward iterator.

The forward iterator for Michael's set is based on 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:

class iterator {
public:
// Default constructor
// 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;
};

§ raw_ptr

template<class RCU , class T , class Traits = split_list::traits>
typedef implementation_defined cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::raw_ptr

pointer to the node for get() function

For LazyList, raw_ptr is just pointer to value_type.

For MichaelList, raw_ptr is cds::urcu::raw_ptr object giving access to value_type.

§ rcu_lock

template<class RCU , class T , class Traits = split_list::traits>
typedef base_class::rcu_lock cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::rcu_lock

RCU scoped lock

Constructor & Destructor Documentation

§ SplitListSet() [1/2]

template<class RCU , class T , class Traits = split_list::traits>
cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::SplitListSet ( )
inline

Initializes split-ordered list of default capacity.

The default capacity is defined in bucket table constructor. See intrusive::split_list::expandable_bucket_table, intrusive::split_list::static_bucket_table which selects by container::split_list::dynamic_bucket_table option.

§ SplitListSet() [2/2]

template<class RCU , class T , class Traits = split_list::traits>
cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::SplitListSet ( size_t  nItemCount,
size_t  nLoadFactor = 1 
)
inline

Initializes split-ordered list.

Parameters
nItemCountestimated average of item count
nLoadFactorload factor - average item count per bucket. Small integer up to 8, default is 1.

Member Function Documentation

§ begin()

template<class RCU , class T , class Traits = split_list::traits>
iterator cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::begin ( )
inline

Returns a forward iterator addressing the first element in a set.

For empty set

begin() == end()

§ contains() [1/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::contains ( Q const &  key)
inline

Checks whether the set contains key.

The function searches the item with key equal to key and returns true if it is found, and false otherwise.

Note the hash functor specified for class Traits template parameter should accept a parameter of type Q that can be not the same as value_type. Otherwise, you may use contains( Q const&, Less pred ) functions with explicit predicate for key comparing.

The function applies RCU lock internally.

§ contains() [2/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::contains ( Q const &  key,
Less  pred 
)
inline

Checks whether the map contains key using pred predicate for searching.

The function is similar to contains( key ) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the map.

§ emplace()

template<class RCU , class T , class Traits = split_list::traits>
template<typename... Args>
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::emplace ( Args &&...  args)
inline

Inserts data of type value_type created from args.

Returns true if inserting successful, false otherwise.

The function applies RCU lock internally.

§ empty()

template<class RCU , class T , class Traits = split_list::traits>
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::empty ( ) const
inline

Checks if the set is empty.

Emptiness is checked by item counting: if item count is zero then assume that the set is empty. Thus, the correct item counting feature is an important part of split-list set implementation.

§ end()

template<class RCU , class T , class Traits = split_list::traits>
iterator cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::end ( )
inline

Returns an iterator that addresses the location succeeding the last element in a set.

Do not use the value returned by end function to access any item. The returned value can be used only to control reaching the end of the set. For empty set

begin() == end()

§ erase() [1/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::erase ( Q const &  key)
inline

Deletes key from the set.

Template parameter of type Q defines the key type searching in the list. The set item comparator should be able to compare the values of type value_type and the type Q.

RCU synchronize method can be called. RCU should not be locked.

Return true if key is found and deleted, false otherwise

§ erase() [2/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::erase ( Q const &  key,
Func  f 
)
inline

Deletes key from the set.

The function searches an item with key key, calls f functor and deletes the item. If key is not found, the functor is not called.

The functor Func interface:

struct extractor {
void operator()(value_type const& val);
};

Template parameter of type Q defines the key type searching in the list. The list item comparator should be able to compare the values of the type value_type and the type Q.

RCU synchronize method can be called. RCU should not be locked.

Return true if key is found and deleted, false otherwise

§ erase_with() [1/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::erase_with ( Q const &  key,
Less  pred 
)
inline

Deletes the item from the set using pred predicate for searching.

The function is an analog of erase(Q const&) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ erase_with() [2/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less , typename Func >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::erase_with ( Q const &  key,
Less  pred,
Func  f 
)
inline

Deletes the item from the set using pred predicate for searching.

The function is an analog of erase(Q const&, Func) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ extract()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q >
exempt_ptr cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::extract ( Q const &  key)
inline

Extracts an item from the set.

The function searches an item with key equal to key in the set, unlinks it from the set, and returns exempt_ptr pointer to the item found. If the item with the key equal to key is not found the function returns an empty exempt_ptr.

Depends on bucket_type you should or should not lock RCU before calling of this function:

  • for the set based on MichaelList RCU should not be locked
  • for the set based on LazyList RCU should be locked See ordered list implementation for details.
typedef cds::urcu::gc< general_buffered<> > rcu;
// Split-list set based on MichaelList by default
splitlist_set theSet;
// ...
splitlist_set::exempt_ptr p;
// For MichaelList we should not lock RCU
// Now, you can apply extract function
p = theSet.extract( 10 );
if ( p ) {
// do something with p
...
}
// We may safely release p here
// release() passes the pointer to RCU reclamation cycle
p.release();

§ extract_with()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less >
exempt_ptr cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::extract_with ( Q const &  key,
Less  pred 
)
inline

Extracts an item from the set using pred predicate for searching.

The function is an analog of extract(Q const&) but pred is used for key comparing. Less functor has the interface like std::less. pred must imply the same element order as the comparator used for building the set.

§ find()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::find ( Q &  key,
Func  f 
)
inline

Finds the key key.

The function searches the item with key equal to key and calls the functor f for item found. The interface of Func functor is:

struct functor {
void operator()( value_type& item, Q& key );
};

where item is the item found, key is the find function argument.

The functor may change non-key fields of item. Note that the functor is only guarantee that item cannot be disposed during functor is executing. The functor does not serialize simultaneous access to the set's item. If such access is possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.

Note the hash functor specified for class Traits template parameter should accept a parameter of type Q that can be not the same as value_type.

The function makes RCU lock internally.

The function returns true if key is found, false otherwise.

§ find_with()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less , typename Func >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::find_with ( Q &  key,
Less  pred,
Func  f 
)
inline

Finds the key key using pred predicate for searching.

The function is an analog of find(Q&, Func) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ get()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q >
raw_ptr cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::get ( Q const &  key)
inline

Finds the key key and return the item found.

The function searches the item with key equal to key and returns the pointer to item found. If key is not found it returns nullptr.

Note the compare functor should accept a parameter of type Q that can be not the same as value_type.

RCU should be locked before call of this function. Returned item is valid only while RCU is locked:

typedef cds::urcu::gc< general_buffered<> > rcu;
splitlist_set theSet;
// ...
{
// Lock RCU
splitlist_set::rcu_lock lock;
foo * pVal = theSet.get( 5 );
if ( pVal ) {
// Deal with pVal
//...
}
// Unlock RCU by rcu_lock destructor
// pVal can be retired by disposer at any time after RCU has been unlocked
}

§ get_with()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Less >
raw_ptr cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::get_with ( Q const &  key,
Less  pred 
)
inline

Finds the key key and return the item found.

The function is an analog of get(Q const&) but pred is used for comparing the keys.

Less functor has the semantics like std::less but should take arguments of type value_type and Q in any order. pred must imply the same element order as the comparator used for building the set.

§ insert() [1/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::insert ( Q const &  val)
inline

Inserts new node.

The function creates a node with copy of val value and then inserts the node created into the set.

The type Q should contain as minimum the complete key for the node. The object of value_type should be constructible from a value of type Q. In trivial case, Q is equal to value_type.

The function applies RCU lock internally.

Returns true if val is inserted into the set, false otherwise.

§ insert() [2/2]

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::insert ( Q const &  key,
Func  f 
)
inline

Inserts new node.

The function allows to split creating of new item into two part:

  • create item with key only
  • insert new item into the set
  • if inserting is success, calls f functor to initialize value-field of val.

The functor signature is:

void func( value_type& val );

where val is the item inserted. User-defined functor f should guarantee that during changing val no any other changes could be made on this set's item by concurrent threads. The user-defined functor is called only if the inserting is success.

The function applies RCU lock internally.

§ update()

template<class RCU , class T , class Traits = split_list::traits>
template<typename Q , typename Func >
std::pair<bool, bool> cds::container::SplitListSet< cds::urcu::gc< RCU >, T, Traits >::update ( Q const &  val,
Func  func,
bool  bAllowInsert = true 
)
inline

Updates an element with given val.

The operation performs inserting or changing data with lock-free manner.

If the val key not found in the set, then the new item created from val is inserted into the set. Otherwise, the functor func is called with the item found. The functor Func signature is:

struct my_functor {
void operator()( bool bNew, value_type& item, const Q& val );
};

with arguments:

  • bNew - true if the item has been inserted, false otherwise
  • item - item of the set
  • val - argument val passed into the ensure() function

The functor may change non-key fields of the item; however, func must guarantee that during changing no any other modifications could be made on this item by concurrent threads.

The function applies RCU lock internally.

Returns std::pair<bool, bool> where first is true if operation is successful, second is true if new item has been added or false if the item with key already is in the set.Updates the node The operation performs inserting or changing data with lock-free manner.

If key is not found in the set, then key is inserted iff bAllowInsert is true. Otherwise, the functor func is called with item found.

The functor signature is:

struct my_functor {
void operator()( bool bNew, value_type& item, const Q& val );
};

with arguments:

  • bNew - true if the item has been inserted, false otherwise
  • item - item of the set
  • val - argument val passed into the update() function

The functor may change non-key fields of the item.

The function applies RCU lock internally.

Returns std::pair<bool, bool> where first is true if operation is successful, second is true if new item has been added or false if the item with key already is in the map.

Warning
For MichaelList as the bucket see insert item troubleshooting. LazyList provides exclusive access to inserted item and does not require any node-level synchronization.

The documentation for this class was generated from the following file:

cds 2.2.0 Developed by Maxim Khizhinsky aka khizmax 2007 - 2017
Autogenerated Wed Jan 4 2017 08:49:43 by Doxygen 1.8.12