mariadb/storage/innodb_plugin/include/mem0pool.h

129 lines
3.9 KiB
C

/*****************************************************************************
Copyright (c) 1994, 2009, Innobase Oy. All Rights Reserved.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
*****************************************************************************/
/**************************************************//**
@file include/mem0pool.h
The lowest-level memory management
Created 6/9/1994 Heikki Tuuri
*******************************************************/
#ifndef mem0pool_h
#define mem0pool_h
#include "univ.i"
#include "os0file.h"
#include "ut0lst.h"
/** Memory area header */
typedef struct mem_area_struct mem_area_t;
/** Memory pool */
typedef struct mem_pool_struct mem_pool_t;
/** The common memory pool */
extern mem_pool_t* mem_comm_pool;
/** Memory area header */
struct mem_area_struct{
ulint size_and_free; /*!< memory area size is obtained by
anding with ~MEM_AREA_FREE; area in
a free list if ANDing with
MEM_AREA_FREE results in nonzero */
UT_LIST_NODE_T(mem_area_t)
free_list; /*!< free list node */
};
/** Each memory area takes this many extra bytes for control information */
#define MEM_AREA_EXTRA_SIZE (ut_calc_align(sizeof(struct mem_area_struct),\
UNIV_MEM_ALIGNMENT))
/********************************************************************//**
Creates a memory pool.
@return memory pool */
UNIV_INTERN
mem_pool_t*
mem_pool_create(
/*============*/
ulint size); /*!< in: pool size in bytes */
/********************************************************************//**
Allocates memory from a pool. NOTE: This low-level function should only be
used in mem0mem.*!
@return own: allocated memory buffer */
UNIV_INTERN
void*
mem_area_alloc(
/*===========*/
ulint* psize, /*!< in: requested size in bytes; for optimum
space usage, the size should be a power of 2
minus MEM_AREA_EXTRA_SIZE;
out: allocated size in bytes (greater than
or equal to the requested size) */
mem_pool_t* pool); /*!< in: memory pool */
/********************************************************************//**
Frees memory to a pool. */
UNIV_INTERN
void
mem_area_free(
/*==========*/
void* ptr, /*!< in, own: pointer to allocated memory
buffer */
mem_pool_t* pool); /*!< in: memory pool */
/********************************************************************//**
Returns the amount of reserved memory.
@return reserved mmeory in bytes */
UNIV_INTERN
ulint
mem_pool_get_reserved(
/*==================*/
mem_pool_t* pool); /*!< in: memory pool */
/********************************************************************//**
Reserves the mem pool mutex. */
UNIV_INTERN
void
mem_pool_mutex_enter(void);
/*======================*/
/********************************************************************//**
Releases the mem pool mutex. */
UNIV_INTERN
void
mem_pool_mutex_exit(void);
/*=====================*/
/********************************************************************//**
Validates a memory pool.
@return TRUE if ok */
UNIV_INTERN
ibool
mem_pool_validate(
/*==============*/
mem_pool_t* pool); /*!< in: memory pool */
/********************************************************************//**
Prints info of a memory pool. */
UNIV_INTERN
void
mem_pool_print_info(
/*================*/
FILE* outfile,/*!< in: output file to write to */
mem_pool_t* pool); /*!< in: memory pool */
#ifndef UNIV_NONINL
#include "mem0pool.ic"
#endif
#endif