rmm::mr::detail::arena::superblock Class Reference

Represents a large chunk of memory that is exchanged between the global arena and per-thread arenas. More...

#include <arena.hpp>

Inheritance diagram for rmm::mr::detail::arena::superblock:

Collaboration diagram for rmm::mr::detail::arena::superblock:

Public Member Functions
	superblock ()=default
	Construct a default superblock.
	superblock (void *pointer, std::size_t size)
	Construct a superblock given a pointer and size. More...
	superblock (superblock const &)=delete
superblock &	operator= (superblock const &)=delete
	superblock (superblock &&) noexcept=default
superblock &	operator= (superblock &&) noexcept=default
bool	empty () const
	Is this superblock empty? More...
std::size_t	free_blocks () const
	Return the number of free blocks. More...
bool	contains (block const &blk) const
	Whether this superblock contains the given block. More...
bool	fits (std::size_t bytes) const
	Can this superblock fit bytes bytes? More...
bool	is_contiguous_before (superblock const &sblk) const
	Verifies whether this superblock can be merged to the beginning of superblock s. More...
std::pair< superblock, superblock >	split (std::size_t bytes) const
	Split this superblock into two by the given size. More...
superblock	merge (superblock const &sblk) const
	Coalesce two contiguous superblocks into one. More...
block	first_fit (std::size_t size)
	Get the first free block of at least size bytes. More...
void	coalesce (block const &blk)
	Coalesce the given block with other free blocks. More...
std::size_t	total_free_size () const
	Find the total free block size. More...
std::size_t	max_free_size () const
	Find the max free block size. More...
Public Member Functions inherited from rmm::mr::detail::arena::byte_span
	byte_span ()=default
	Construct a default span.
	byte_span (void *pointer, std::size_t size)
	Construct a span given a pointer and size. More...
char *	pointer () const
	Returns the underlying pointer.
std::size_t	size () const
	Returns the size of the span.
char *	end () const
	Returns the end of the span.
bool	is_valid () const
	Returns true if this span is valid (non-null), false otherwise.
bool	operator< (byte_span const &span) const
	Used by std::set to compare spans.

Static Public Attributes
static constexpr std::size_t	minimum_size {1UL << 20}
	Minimum size of a superblock (1 MiB).
static constexpr std::size_t	maximum_size {1UL << 40}
	Maximum size of a superblock (1 TiB), as a sanity check.

Detailed Description

Represents a large chunk of memory that is exchanged between the global arena and per-thread arenas.

Constructor & Destructor Documentation

superblock()

rmm::mr::detail::arena::superblock::superblock ( void *  pointer, std::size_t  size  )

inline

Construct a superblock given a pointer and size.

Parameters

pointer	The address for the beginning of the superblock.
size	The size of the superblock.

Member Function Documentation

coalesce()

void rmm::mr::detail::arena::superblock::coalesce ( block const &  blk )

inline

Coalesce the given block with other free blocks.

Parameters

blk	The block to coalesce.

contains()

bool rmm::mr::detail::arena::superblock::contains ( block const &  blk ) const

inline

Whether this superblock contains the given block.

Parameters

blk	The block to search for.

Returns

true if the given block belongs to this superblock.

empty()

bool rmm::mr::detail::arena::superblock::empty ( ) const

inline

Is this superblock empty?

Returns

true if this superblock is empty.

first_fit()

block rmm::mr::detail::arena::superblock::first_fit ( std::size_t  size )

inline

Get the first free block of at least size bytes.

Parameters

size	The number of bytes to allocate.

Returns

block A block of memory of at least size bytes, or an empty block if not found.

fits()

bool rmm::mr::detail::arena::superblock::fits ( std::size_t  bytes ) const

inline

Can this superblock fit bytes bytes?

Parameters

bytes

The size in bytes to check for fit.

Returns

true if this superblock can fit bytes bytes.

free_blocks()

std::size_t rmm::mr::detail::arena::superblock::free_blocks ( ) const

inline

Return the number of free blocks.

Returns

the number of free blocks.

is_contiguous_before()

bool rmm::mr::detail::arena::superblock::is_contiguous_before ( superblock const &  sblk ) const

inline

Verifies whether this superblock can be merged to the beginning of superblock s.

Parameters

s	The superblock to check for contiguity.

Returns

true Returns true if both superblocks are empty and this superblock's pointer + size == s.ptr.

max_free_size()

std::size_t rmm::mr::detail::arena::superblock::max_free_size ( ) const

inline

Find the max free block size.

Returns

the max free block size.

merge()

superblock rmm::mr::detail::arena::superblock::merge ( superblock const &  sblk ) const

inline

Coalesce two contiguous superblocks into one.

this->is_contiguous_before(s) must be true.

Parameters

sblk	superblock to merge.

Returns

block The merged block.

split()

std::pair<superblock, superblock> rmm::mr::detail::arena::superblock::split ( std::size_t  bytes ) const

inline

Split this superblock into two by the given size.

Parameters

bytes

The size in bytes of the first block.

Returns

superblock_pair A pair of superblocks split by bytes.

total_free_size()

std::size_t rmm::mr::detail::arena::superblock::total_free_size ( ) const

inline

Find the total free block size.

Returns

the total free block size.

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

• arena.hpp