Fixed-capacity page of equal-sized blocks. More...

#include <paged_allocator.h>

Inheritance diagram for gaia::mem::MemoryPage< T, RequestedBlockSize >:

Public Types
using	Page = MemoryPage< T, RequestedBlockSize >
	This page type.

using	BlockArray = cnt::sarray< uint8_t, BlockArrayBytes >
	Packed block-index storage.

using	BitView = core::bit_view< NBlocks_Bits >
	View used to read and write packed block indices.

Public Member Functions
	MemoryPage (void *ptr)
	Free bits to use in the future.

void	write_block_idx (uint32_t blockIdx, uint32_t value)
	Writes one link in the packed recycled-block list.

uint8_t	read_block_idx (uint32_t blockIdx) const
	Reads one link from the packed recycled-block list.

GAIA_NODISCARD void *	alloc_block ()
	Allocate a new block for this page.

void	free_block (void *pBlock)
	Release the block allocated by this page.

GAIA_NODISCARD uint32_t	used_blocks_cnt () const
	Returns the number of live blocks.

GAIA_NODISCARD bool	full () const
	Reports whether all page blocks are allocated.

GAIA_NODISCARD bool	empty () const
	Reports whether no page blocks are allocated.

void	verify () const
	Verifies page invariants in assertion-enabled builds.

Public Member Functions inherited from gaia::mem::MemoryPageHeader
	MemoryPageHeader (void *ptr)
	Creates a page header for a backing allocation.

Public Member Functions inherited from gaia::cnt::fwd_llist_base< MemoryPage< T, RequestedBlockSize > >
fwd_llist_link< MemoryPage< T, RequestedBlockSize > > &	get_fwd_llist_link ()
	Returns the mutable intrusive link.

const fwd_llist_link< MemoryPage< T, RequestedBlockSize > > &	get_fwd_llist_link () const
	Returns the immutable intrusive link.

Static Public Member Functions
static constexpr uint32_t	next_multiple_of_alignment (uint32_t num)
	Rounds a size up to MemoryBlockAlignment.

static constexpr uint32_t	calculate_block_size ()
	Selects and aligns the configured block size.

Public Attributes
BlockArray	m_blocks
	Implicit list of blocks.

uint32_t	m_blockCnt: NBlocks_Bits
	Number of blocks in the block array.

uint32_t	m_usedBlocks: NBlocks_Bits
	Number of used blocks out of NBlocks.

uint32_t	m_nextFreeBlock: NBlocks_Bits
	Index of the next block to recycle.

uint32_t	m_freeBlocks: NBlocks_Bits
	Number of blocks to recycle.

Public Attributes inherited from gaia::mem::MemoryPageHeader
void *	m_data
	Pointer to data managed by page.

Public Attributes inherited from gaia::cnt::fwd_llist_base< MemoryPage< T, RequestedBlockSize > >
fwd_llist_link< MemoryPage< T, RequestedBlockSize > >	fwd_link_GAIA
	Intrusive link storage used by fwd_llist.

Static Public Attributes
static constexpr uint32_t	MemoryBlockBytes = calculate_block_size()
	Size of one block in bytes.

static constexpr uint16_t	NBlocks = 48
	Maximum number of blocks in a page.

static constexpr uint16_t	NBlocks_Bits = (uint16_t)core::count_bits(NBlocks)
	Bits required to encode a block index.

static constexpr uint32_t	InvalidBlockId = NBlocks + 1
	Sentinel terminating the recycled-block list.

static constexpr uint32_t	BlockArrayBytes = ((uint32_t)NBlocks_Bits * (uint32_t)NBlocks + 7) / 8
	Bytes occupied by the packed block-index array.

Detailed Description

template<typename T, uint32_t RequestedBlockSize>
struct gaia::mem::MemoryPage< T, RequestedBlockSize >

Fixed-capacity page of equal-sized blocks.

Template Parameters

T	Allocation category used for singleton separation and diagnostics.
RequestedBlockSize	Requested bytes per block, or zero for the default.

Constructor & Destructor Documentation

◆ MemoryPage()

template<typename T , uint32_t RequestedBlockSize>

gaia::mem::MemoryPage< T, RequestedBlockSize >::MemoryPage ( void * ptr )

inline

Free bits to use in the future.

Creates an empty page over a backing allocation.

Parameters

ptr	Backing allocation address.

Member Function Documentation

◆ alloc_block()

template<typename T , uint32_t RequestedBlockSize>

GAIA_NODISCARD void * gaia::mem::MemoryPage< T, RequestedBlockSize >::alloc_block ( )

inline

Allocate a new block for this page.

Returns: Pointer to the usable block storage.

◆ calculate_block_size()

template<typename T , uint32_t RequestedBlockSize>

static constexpr uint32_t gaia::mem::MemoryPage< T, RequestedBlockSize >::calculate_block_size ( )

inlinestaticconstexpr

Selects and aligns the configured block size.

Returns: Block size in bytes.

◆ empty()

template<typename T , uint32_t RequestedBlockSize>

GAIA_NODISCARD bool gaia::mem::MemoryPage< T, RequestedBlockSize >::empty ( ) const

inline

Reports whether no page blocks are allocated.

Returns: True when the page is empty.

◆ free_block()

template<typename T , uint32_t RequestedBlockSize>

void gaia::mem::MemoryPage< T, RequestedBlockSize >::free_block ( void * pBlock )

inline

Release the block allocated by this page.

Parameters

pBlock Pointer previously returned by alloc_block().

◆ full()

template<typename T , uint32_t RequestedBlockSize>

GAIA_NODISCARD bool gaia::mem::MemoryPage< T, RequestedBlockSize >::full ( ) const

inline

Reports whether all page blocks are allocated.

Returns: True when the page is full.

◆ next_multiple_of_alignment()

template<typename T , uint32_t RequestedBlockSize>

static constexpr uint32_t gaia::mem::MemoryPage< T, RequestedBlockSize >::next_multiple_of_alignment ( uint32_t num )

inlinestaticconstexpr

Rounds a size up to MemoryBlockAlignment.

Parameters

num	Size in bytes.

Returns: Aligned size in bytes.

◆ read_block_idx()

template<typename T , uint32_t RequestedBlockSize>

uint8_t gaia::mem::MemoryPage< T, RequestedBlockSize >::read_block_idx ( uint32_t blockIdx ) const

inline

Reads one link from the packed recycled-block list.

Parameters

blockIdx Block whose link is read.

Returns: Linked block index or InvalidBlockId.

◆ used_blocks_cnt()

template<typename T , uint32_t RequestedBlockSize>

GAIA_NODISCARD uint32_t gaia::mem::MemoryPage< T, RequestedBlockSize >::used_blocks_cnt ( ) const

inline

Returns the number of live blocks.

Returns: Number of allocated blocks.

◆ write_block_idx()

template<typename T , uint32_t RequestedBlockSize>

void gaia::mem::MemoryPage< T, RequestedBlockSize >::write_block_idx	(	uint32_t	blockIdx,
		uint32_t	value
	)

inline

Writes one link in the packed recycled-block list.

Parameters

blockIdx	Block whose link is updated.
value	Linked block index or InvalidBlockId.

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

/home/runner/work/gaia-ecs/gaia-ecs/include/gaia/mem/paged_allocator.h

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Static Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ MemoryPage()

Member Function Documentation

◆ alloc_block()

◆ calculate_block_size()

◆ empty()

◆ free_block()

◆ full()

◆ next_multiple_of_alignment()

◆ read_block_idx()

◆ used_blocks_cnt()

◆ write_block_idx()