This group discusses the functions that provide memory pool management. More...

Typedefs
typedef struct _Eina_Mempool	Eina_Mempool
	The opaque type for the mempool structure.

typedef struct _Eina_Mempool_Backend	Eina_Mempool_Backend
	The opaque type for the mempool backend type.

typedef void(*	Eina_Mempool_Repack_Cb) (void dst, void src, void *data)
	The callback type which is called when the mempool "repacks" its data.

Functions
EINA_API Eina_Mempool *	eina_mempool_add (const char name, const char context, const char *options,...)
	Creates a new mempool of the given type.

EINA_API void	eina_mempool_del (Eina_Mempool *mp)
	Deletes the given mempool.

static void *	eina_mempool_realloc (Eina_Mempool mp, void element, unsigned int size)
	Re-allocates an amount memory by the given mempool.

static void *	eina_mempool_malloc (Eina_Mempool *mp, unsigned int size)
	Allocates memory using the given mempool.

static void *	eina_mempool_malloc_near (Eina_Mempool mp, void after, void *before, unsigned int size)
	Allocates memory in the given mempool using locality hint to improve future memory access use.

static void *	eina_mempool_calloc (Eina_Mempool *mp, unsigned int size)
	Allocates and zeros memory using the given mempool.

static void	eina_mempool_free (Eina_Mempool mp, void element)
	Frees resources previously allocated by the given mempool.

EINA_API void	eina_mempool_repack (Eina_Mempool mp, Eina_Mempool_Repack_Cb cb, void data)
	Repacks the objects in the mempool.

EINA_API void	eina_mempool_gc (Eina_Mempool *mp)
	Runs a garbage collection cycle.

static Eina_Bool	eina_mempool_from (Eina_Mempool mp, void element)
	Check if a pointer is a valid element from the mempool.

EINA_API void	eina_mempool_statistics (Eina_Mempool *mp)
	Has the backend update its internal statistics.

static Eina_Iterator *	eina_mempool_iterator_new (Eina_Mempool *mp)
	Provide an iterator to walk all allocated elements from a specified mempool.

EINA_API Eina_Bool	eina_mempool_register (Eina_Mempool_Backend *be)
	Registers the given memory pool backend.

EINA_API void	eina_mempool_unregister (Eina_Mempool_Backend *be)
	Unregisters the given memory pool backend.

static unsigned int	eina_mempool_alignof (unsigned int size)
	Computes the alignment that would be used when allocating a object of size `size`.

Variables
EINA_API Eina_Error	EINA_ERROR_NOT_MEMPOOL_MODULE

Detailed Description

This group discusses the functions that provide memory pool management.

Several mempools are available:

chained_pool: It is the default one. It allocates a big chunk of memory with malloc() and splits the result into chunks of the requested size that are pushed inside a stack. When requested, it takes this pointer from the stack to give them to whoever wants them.
pass_through: it just call malloc() and free(). It may be faster on some computers than using our own allocators (like having a huge L2 cache, over 4MB).
one_big: It calls malloc() just one time for the requested number of items. This is useful when you know in advance how many objects of some type live during the life of the mempool.

Typedef Documentation

◆ Eina_Mempool_Repack_Cb

Eina_Mempool_Repack_Cb

The callback type which is called when the mempool "repacks" its data.

I.e. moves it around to optimize the way it is stored in memory. This is useful to improve data locality and to free internal pools back to the OS.

Note: The callback needs to update users of the data to stop accessing the object from the old location and access it using the new location instead. The copy of memory is taken care of by the mempool.

Function Documentation

◆ eina_mempool_add()

EINA_API Eina_Mempool * eina_mempool_add	(	const char *	name,
		const char *	context,
		const char *	options,
			...
	)

Creates a new mempool of the given type.

Parameters

[in]	name	Name of the mempool kind to use.
[in]	context	Identifier of the mempool created (for debug purposes).
[in]	options	Unused. Use the variable arguments list instead to pass options to the mempool.
[in]	...	Additional options to pass to the allocator; depends entirely on the type of mempool ("int pool size" for chained and "int item_size" for one_big.

Returns: Newly allocated mempool instance, NULL otherwise.

References EINA_SAFETY_ON_NULL_RETURN_VAL.

Referenced by edje_init(), and eina_cow_add().

◆ eina_mempool_del()

EINA_API void eina_mempool_del ( Eina_Mempool * mp )

Deletes the given mempool.

Parameters

[in] mp The mempool to delete

References EINA_SAFETY_ON_NULL_RETURN.

Referenced by edje_init(), and eina_cow_del().

◆ eina_mempool_realloc()

static void * eina_mempool_realloc	(	Eina_Mempool *	mp,
		void *	element,
		unsigned int	size
	)

inlinestatic

Re-allocates an amount memory by the given mempool.

Parameters

[in]	mp	The mempool
[in]	element	The element to re-allocate
[in]	size	The size in bytes to re-allocate

Returns: The newly re-allocated data

Note: This function re-allocates and returns element with size bytes using the mempool mp. If not used anymore, the data must be freed with eina_mempool_free().

Warning: No checks are done for mp.

See also: eina_mempool_free()

◆ eina_mempool_malloc()

static void * eina_mempool_malloc	(	Eina_Mempool *	mp,
		unsigned int	size
	)

inlinestatic

Allocates memory using the given mempool.

Parameters

[in]	mp	The mempool
[in]	size	The size in bytes to allocate

Returns: The newly allocated data

Note: This function allocates and returns size bytes using the mempool mp. If not used anymore, the data must be freed with eina_mempool_free().

Warning: No checks are done for mp.

See also: eina_mempool_free()

◆ eina_mempool_malloc_near()

static void * eina_mempool_malloc_near	(	Eina_Mempool *	mp,
		void *	after,
		void *	before,
		unsigned int	size
	)

inlinestatic

Allocates memory in the given mempool using locality hint to improve future memory access use.

Parameters

[in]	mp	The mempool
[in]	after	Hint to the nearest pointer after which to try find an empty spot.
[in]	before	Hint to the nearest pointer before which to try find an empty spot.
[in]	size	The size in bytes to allocate

Returns: The newly allocated data that might be near after and before.

This function is to be used to improve cache locality of structure that are likely to be used one after another. An example of this use would be Eina_List.

Note: This function allocates and returns size bytes using the mempool mp. If not used anymore, the data must be freed with eina_mempool_free().; after and before must be either NULL or allocated by the same mempool mp. They are hint and if no space near them is found, memory will be allocated without locality improvement.

Warning: No checks are done for mp.

See also: eina_mempool_free()

◆ eina_mempool_calloc()

static void * eina_mempool_calloc	(	Eina_Mempool *	mp,
		unsigned int	size
	)

inlinestatic

Allocates and zeros memory using the given mempool.

Parameters

[in]	mp	The mempool
[in]	size	The size in bytes to allocate

Returns: The newly allocated data

This function allocates, zeroes, and returns size bytes using the mempool mp. If not used anymore, the data must be freed with eina_mempool_free().

Warning: No checks are done for mp.

Since: 1.2

See also: eina_mempool_free()

◆ eina_mempool_free()

static void eina_mempool_free	(	Eina_Mempool *	mp,
		void *	element
	)

inlinestatic

Frees resources previously allocated by the given mempool.

Parameters

[in]	mp	The mempool
[in]	element	The data to free

This function frees element allocated by mp. element must have been obtained from eina_mempool_malloc(), eina_mempool_calloc(), or eina_mempool_realloc().

Warning: No checks are done for mp.

See also: eina_mempool_malloc(); eina_mempool_calloc(); eina_mempool_realloc()

◆ eina_mempool_repack()

EINA_API void eina_mempool_repack	(	Eina_Mempool *	mp,
		Eina_Mempool_Repack_Cb	cb,
		void *	data
	)

Repacks the objects in the mempool.

Parameters

[in]	mp	The mempool
[in]	cb	A callback to update the pointers the objects with their new location
[in]	data	Data to pass as third argument to `cb`

See also: Eina_Mempool_Repack_Cb; _Eina_Mempool_Backend

References EINA_SAFETY_ON_NULL_RETURN.

◆ eina_mempool_gc()

EINA_API void eina_mempool_gc ( Eina_Mempool * mp )

Runs a garbage collection cycle.

Parameters

[in] mp The mempool

References EINA_SAFETY_ON_NULL_RETURN.

◆ eina_mempool_from()

static Eina_Bool eina_mempool_from	(	Eina_Mempool *	mp,
		void *	element
	)

inlinestatic

Check if a pointer is a valid element from the mempool.

Parameters

[in]	mp	The mempool
[in]	element	The data to free

Returns: EINA_TRUE if the element is a valid element of the mempool, EINA_FALSE otherwise

Since: 1.20

◆ eina_mempool_statistics()

EINA_API void eina_mempool_statistics ( Eina_Mempool * mp )

Has the backend update its internal statistics.

Parameters

[in] mp The mempool

References EINA_SAFETY_ON_NULL_RETURN.

◆ eina_mempool_iterator_new()

static Eina_Iterator * eina_mempool_iterator_new ( Eina_Mempool * mp )

inlinestatic

Provide an iterator to walk all allocated elements from a specified mempool.

Parameters

[in] mp The mempool

Returns: NULL if it is not possible to iterate over the mempool, a valid iterator otherwise.

Note: This call is expected to be slow and should not be used in any performance critical area.

Since: 1.23

◆ eina_mempool_register()

EINA_API Eina_Bool eina_mempool_register ( Eina_Mempool_Backend * be )

Registers the given memory pool backend.

Parameters

[in] be The backend

Returns: EINA_TRUE if backend has been correctly registered, EINA_FALSE otherwise.

References eina_hash_add(), EINA_SAFETY_ON_NULL_RETURN_VAL, and _Eina_Mempool_Backend::name.

◆ eina_mempool_unregister()

EINA_API void eina_mempool_unregister ( Eina_Mempool_Backend * be )

Unregisters the given memory pool backend.

Parameters

[in] be The backend

References eina_hash_del(), EINA_SAFETY_ON_NULL_RETURN, and _Eina_Mempool_Backend::name.

◆ eina_mempool_alignof()

static unsigned int eina_mempool_alignof ( unsigned int size )

inlinestatic

Computes the alignment that would be used when allocating a object of size size.

Parameters

[in] size

Returns: The alignment for an allocation of size size.

References EINA_UNLIKELY.

Referenced by eina_cow_add().

Typedefs

Functions

Variables

Detailed Description

Typedef Documentation

◆ Eina_Mempool_Repack_Cb

Function Documentation

◆ eina_mempool_add()

◆ eina_mempool_del()

◆ eina_mempool_realloc()

◆ eina_mempool_malloc()

◆ eina_mempool_malloc_near()

◆ eina_mempool_calloc()

◆ eina_mempool_free()

◆ eina_mempool_repack()

◆ eina_mempool_gc()

◆ eina_mempool_from()

◆ eina_mempool_statistics()

◆ eina_mempool_iterator_new()

◆ eina_mempool_register()

◆ eina_mempool_unregister()

◆ eina_mempool_alignof()