Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink > Class Template Reference

#include "MPSCQueue.h"

Public Member Functions
	MPSCQueueIntrusive ()
	~MPSCQueueIntrusive ()
void	Enqueue (T *input)
bool	Dequeue (T *&result)

Private Member Functions
	MPSCQueueIntrusive (MPSCQueueIntrusive const &)=delete
MPSCQueueIntrusive &	operator= (MPSCQueueIntrusive const &)=delete

Private Attributes
std::aligned_storage_t< sizeof(T), alignof(T)>	_dummy
T *	_dummyPtr
std::atomic< T * >	_head
std::atomic< T * >	_tail

Detailed Description

template<typename T, std::atomic< T * > T::* IntrusiveLink>
class Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >

Constructor & Destructor Documentation

MPSCQueueIntrusive() [1/2]

template<typename T , std::atomic< T * > T::* IntrusiveLink>

Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::MPSCQueueIntrusive ( )

inline

                             : _dummyPtr(reinterpret_cast<T*>(std::addressof(_dummy))), _head(_dummyPtr), _tail(_dummyPtr)
        {
            // _dummy is constructed from aligned_storage and is intentionally left uninitialized (it might not be default constructible)
            // so we init only its IntrusiveLink here
            std::atomic<T*>* dummyNext = new (&(_dummyPtr->*IntrusiveLink)) std::atomic<T*>();
            dummyNext->store(nullptr, std::memory_order_relaxed);
        }

References Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_dummyPtr.

~MPSCQueueIntrusive()

template<typename T , std::atomic< T * > T::* IntrusiveLink>

Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::~MPSCQueueIntrusive ( )

inline

        {
            T* output;
            while (Dequeue(output))
                delete output;
        }

References Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue().

MPSCQueueIntrusive() [2/2]

template<typename T , std::atomic< T * > T::* IntrusiveLink>

Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::MPSCQueueIntrusive ( MPSCQueueIntrusive< T, IntrusiveLink > const &  )

privatedelete

Member Function Documentation

Dequeue()

template<typename T , std::atomic< T * > T::* IntrusiveLink>

bool Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue ( T *&  result )

inline

        {
            T* tail = _tail.load(std::memory_order_relaxed);
            T* next = (tail->*IntrusiveLink).load(std::memory_order_acquire);
            if (tail == _dummyPtr)
            {
                if (!next)
                    return false;
 
                _tail.store(next, std::memory_order_release);
                tail = next;
                next = (next->*IntrusiveLink).load(std::memory_order_acquire);
            }
 
            if (next)
            {
                _tail.store(next, std::memory_order_release);
                result = tail;
                return true;
            }
 
            T* head = _head.load(std::memory_order_acquire);
            if (tail != head)
                return false;
 
            Enqueue(_dummyPtr);
            next = (tail->*IntrusiveLink).load(std::memory_order_acquire);
            if (next)
            {
                _tail.store(next, std::memory_order_release);
                result = tail;
                return true;
            }
            return false;
        }

References Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_dummyPtr, Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_head, Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_tail, and Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Enqueue().

Referenced by Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::~MPSCQueueIntrusive().

Enqueue()

template<typename T , std::atomic< T * > T::* IntrusiveLink>

void Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Enqueue ( T *  input )

inline

        {
            (input->*IntrusiveLink).store(nullptr, std::memory_order_release);
            T* prevHead = _head.exchange(input, std::memory_order_acq_rel);
            (prevHead->*IntrusiveLink).store(input, std::memory_order_release);
        }

References Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_head.

Referenced by Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue().

operator=()

template<typename T , std::atomic< T * > T::* IntrusiveLink>

MPSCQueueIntrusive & Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::operator= ( MPSCQueueIntrusive< T, IntrusiveLink > const &  )

privatedelete

Member Data Documentation

_dummy

template<typename T , std::atomic< T * > T::* IntrusiveLink>

std::aligned_storage_t<sizeof(T), alignof(T)> Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_dummy

private

_dummyPtr

template<typename T , std::atomic< T * > T::* IntrusiveLink>

T* Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_dummyPtr

private

Referenced by Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue(), and Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::MPSCQueueIntrusive().

_head

template<typename T , std::atomic< T * > T::* IntrusiveLink>

std::atomic<T*> Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_head

private

Referenced by Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue(), and Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Enqueue().

_tail

template<typename T , std::atomic< T * > T::* IntrusiveLink>

std::atomic<T*> Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::_tail

private

Referenced by Acore::Impl::MPSCQueueIntrusive< T, IntrusiveLink >::Dequeue().