Files
file	rkhmempool.h
	Specifies the interface of the fixed-size memory blocks facility.

Data Structures
struct	RKH_MEMPOOL_T
	Defines the data structure used to memory block pool facility. More...

Functions
void	rkh_memPool_init (RKH_MEMPOOL_T mp, void sstart, rui16_t ssize, RKH_MPBS_T bsize)
	Initializes the previously allocated memory pool data strcuture RKH_MEMPOOL_T. More...

void *	rkh_memPool_get (RKH_MEMPOOL_T *mp)
	Get a memory block from one of the previously allocated memory pool. More...

void	rkh_memPool_put (RKH_MEMPOOL_T mp, void blk)
	When the application is done with the memory block, it must be returned to the appropiate memory pool. The block must be allocated from the same memory pool to which it is returned. More...

RKH_MPBS_T	rkh_memPool_get_bsize (RKH_MEMPOOL_T *mp)
	Retrieves the size of memory block in bytes. More...

RKH_MPNB_T	rkh_memPool_get_nfree (RKH_MEMPOOL_T *mp)
	Retrieves the current number of free memory blocks in the pool. More...

RKH_MPNB_T	rkh_memPool_get_low_wmark (RKH_MEMPOOL_T *mp)
	Retrieves the lowest number of free blocks ever present in the pool. This number provides valuable empirical data for proper sizing of the memory pool. More...

void	rkh_memPool_get_info (RKH_MEMPOOL_T mp, RKH_MPI_T mpi)
	Retrieves performance information for a particular memory pool. More...

void	rkh_memPool_clear_info (RKH_MEMPOOL_T *mp)
	Clear performance information for a particular memory pool. More...

Detailed Description

Function Documentation

void rkh_memPool_init	(	RKH_MEMPOOL_T *	mp,
		void *	sstart,
		rui16_t	ssize,
		RKH_MPBS_T	bsize
	)

Initializes the previously allocated memory pool data strcuture RKH_MEMPOOL_T.

A memory block pool is declared with the RKH_MEMPOOL_T data type and is defined with the rkh_memPool_init() service.

A general challenge in writing this function is portability, because storage allocation is intrinsically machine-dependent. Perhaps the trickiest aspect here is the proper and optimal alignment of the blocks within the contiguous memory buffer. In particular, the alignment of blocks must be such that every new block can be treated as a pointer to the next block [MS]. Internally, this function rounds up the block size so that it can fit an integer number of pointers. This is done to achieve proper alignment of the blocks within the pool. Due to the rounding of block size the actual capacity of the pool might be less than (pool_size/blk_size). [MS]

Check the capacity of the pool by calling the rkh_memPool_get_nfree() function.

Parameters

[in]	mp	pointer to previously allocated memory pool structure.
[in]	sstart	storage start. Pointer to memory from which memory blocks are allocated.
[in]	ssize	storage size. Size of the memory pool storage in bytes.
[in]	bsize	block size. This number determines the size of each memory block in the pool.

Note: See RKH_MEMPOOL_T structure for more information.

void* rkh_memPool_get ( RKH_MEMPOOL_T * mp )

Get a memory block from one of the previously allocated memory pool.

Parameters

[in] mp pointer to previously allocated memory pool structure.

Returns: A pointer to a new memory block or NULL if the pool runs out of blocks.

void rkh_memPool_put	(	RKH_MEMPOOL_T *	mp,
		void *	blk
	)

When the application is done with the memory block, it must be returned to the appropiate memory pool. The block must be allocated from the same memory pool to which it is returned.

Parameters

[in]	mp	pointer to previously allocated memory pool structure.
[in]	blk	pointer to the returned memory block.

RKH_MPBS_T rkh_memPool_get_bsize ( RKH_MEMPOOL_T * mp )

Retrieves the size of memory block in bytes.

Parameters

[in] mp pointer to previously allocated memory pool structure.

Returns: The size of memory block in bytes.

Note: This function is optional, thus it could be eliminated in compile-time with RKH_CFG_MP_GET_BSIZE_EN.

RKH_MPNB_T rkh_memPool_get_nfree ( RKH_MEMPOOL_T * mp )

Retrieves the current number of free memory blocks in the pool.

Parameters

[in] mp pointer to previously allocated memory pool structure.

Returns: The number of free memory blocks in the pool.

Note: This function is optional, thus it could be eliminated in compile-time with RKH_CFG_MP_GET_NFREE_EN.

RKH_MPNB_T rkh_memPool_get_low_wmark ( RKH_MEMPOOL_T * mp )

Retrieves the lowest number of free blocks ever present in the pool. This number provides valuable empirical data for proper sizing of the memory pool.

Parameters

[in] mp pointer to previously allocated memory pool structure.

Returns: Lowest number of free blocks ever present in the pool.

Note: This function is optional, thus it could be eliminated in compile-time with RKH_CFG_MP_GET_LWM_EN.

void rkh_memPool_get_info	(	RKH_MEMPOOL_T *	mp,
		RKH_MPI_T *	mpi
	)

Retrieves performance information for a particular memory pool.

Information is available during run-time for each of the RKSYS resources. This information can be useful in determining whether the application is performing properly, as well as helping to optimize the application.

Parameters

[in]	mp	pointer to previously allocated memory pool structure.
[in]	mpi	pointer to the buffer into which the performance information will be copied by reference.

Note: This function is optional, thus it could be eliminated in compile-time with RKH_CFG_MP_GET_INFO_EN.

void rkh_memPool_clear_info ( RKH_MEMPOOL_T * mp )

Clear performance information for a particular memory pool.

Parameters

[in] mp pointer to previously allocated memory pool structure.

Note: This function is optional, thus it could be eliminated in compile-time with RKH_CFG_MP_GET_INFO_EN.

Files

Data Structures

Functions

Detailed Description

Function Documentation