xrpl::SlabAllocator< Type > Class Template Reference

#include <SlabAllocator.h>

Collaboration diagram for xrpl::SlabAllocator< Type >:

Classes
struct	SlabBlock
	A block of memory that is owned by a slab allocator. More...

Public Member Functions
constexpr	SlabAllocator (std::size_t extra, std::size_t alloc=0, std::size_t align=0)
	Constructs a slab allocator able to allocate objects of a fixed size.
	SlabAllocator (SlabAllocator const &other)=delete
SlabAllocator &	operator= (SlabAllocator const &other)=delete
	SlabAllocator (SlabAllocator &&other)=delete
SlabAllocator &	operator= (SlabAllocator &&other)=delete
	~SlabAllocator ()=default
constexpr std::size_t	size () const noexcept
	Returns the size of the memory block this allocator returns.
std::uint8_t *	allocate () noexcept
	Returns a suitably aligned pointer, if one is available.
bool	deallocate (std::uint8_t *ptr) noexcept
	Returns the memory block to the allocator.

Private Attributes
std::atomic< SlabBlock * >	slabs_ = nullptr
std::size_t const	itemAlignment_
std::size_t const	itemSize_
std::size_t const	slabSize_

Detailed Description

template<typename Type>
class xrpl::SlabAllocator< Type >

Definition at line 27 of file SlabAllocator.h.

Constructor & Destructor Documentation

SlabAllocator() [1/3]

template<typename Type>

xrpl::SlabAllocator< Type >::SlabAllocator ( std::size_t extra, std::size_t alloc = 0, std::size_t align = 0 )

explicitconstexpr

Constructs a slab allocator able to allocate objects of a fixed size.

Parameters

count

the number of items the slab allocator can allocate; note that a count of 0 is valid and means that the allocator is, effectively, disabled. This can be very useful in some contexts (e.g. when minimal memory usage is needed) and allows for graceful failure.

Definition at line 155 of file SlabAllocator.h.

SlabAllocator() [2/3]

template<typename Type>

xrpl::SlabAllocator< Type >::SlabAllocator ( SlabAllocator< Type > const & other )

delete

SlabAllocator() [3/3]

template<typename Type>

xrpl::SlabAllocator< Type >::SlabAllocator ( SlabAllocator< Type > && other )

delete

~SlabAllocator()

template<typename Type>

xrpl::SlabAllocator< Type >::~SlabAllocator ( )

default

Member Function Documentation

operator=() [1/2]

template<typename Type>

SlabAllocator & xrpl::SlabAllocator< Type >::operator= ( SlabAllocator< Type > const & other )

delete

operator=() [2/2]

template<typename Type>

SlabAllocator & xrpl::SlabAllocator< Type >::operator= ( SlabAllocator< Type > && other )

delete

size()

template<typename Type>

std::size_t xrpl::SlabAllocator< Type >::size ( ) const

nodiscardconstexprnoexcept

Returns the size of the memory block this allocator returns.

Definition at line 183 of file SlabAllocator.h.

allocate()

template<typename Type>

std::uint8_t * xrpl::SlabAllocator< Type >::allocate ( )

noexcept

Returns a suitably aligned pointer, if one is available.

Returns

a pointer to a block of memory from the allocator, or nullptr if the allocator can't satisfy this request.

Definition at line 194 of file SlabAllocator.h.

deallocate()

template<typename Type>

bool xrpl::SlabAllocator< Type >::deallocate ( std::uint8_t * ptr )

noexcept

Returns the memory block to the allocator.

Parameters

ptr	A pointer to a memory block.
size	If non-zero, a hint as to the size of the block.

Returns

true if this memory block belonged to the allocator and has been released; false otherwise.

Definition at line 260 of file SlabAllocator.h.

Member Data Documentation

slabs_

template<typename Type>

std::atomic<SlabBlock*> xrpl::SlabAllocator< Type >::slabs_ = nullptr

private

Definition at line 134 of file SlabAllocator.h.

itemAlignment_

template<typename Type>

std::size_t const xrpl::SlabAllocator< Type >::itemAlignment_

private

Definition at line 137 of file SlabAllocator.h.

itemSize_

template<typename Type>

std::size_t const xrpl::SlabAllocator< Type >::itemSize_

private

Definition at line 141 of file SlabAllocator.h.

slabSize_

template<typename Type>

std::size_t const xrpl::SlabAllocator< Type >::slabSize_

private

Definition at line 144 of file SlabAllocator.h.