zephyr/include/misc/mempool.h

103 lines
3.0 KiB
C

/*
* Copyright (c) 2018 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef SYS_MEMPOOL_H
#define SYS_MEMPOOL_H
#include <kernel.h>
#include <misc/mempool_base.h>
struct sys_mem_pool {
struct sys_mem_pool_base base;
struct k_mutex *mutex;
};
struct sys_mem_pool_block {
struct sys_mem_pool *pool;
u32_t level : 4;
u32_t block : 28;
};
/**
* @brief Statically define system memory pool
*
* The memory pool's buffer contains @a n_max blocks that are @a max_size bytes
* long. The memory pool allows blocks to be repeatedly partitioned into
* quarters, down to blocks of @a min_size bytes long. The buffer is aligned
* to a @a align -byte boundary.
*
* If the pool is to be accessed outside the module where it is defined, it
* can be declared via
*
* @code extern struct sys_mem_pool <name>; @endcode
*
* This pool will not be in an initialized state. You will still need to
* run sys_mem_pool_init() on it before using any other APIs.
*
* @param name Name of the memory pool.
* @param kmutex Pointer to an initialized k_mutex object, used for
* synchronization, declared with K_MUTEX_DEFINE().
* @param minsz Size of the smallest blocks in the pool (in bytes).
* @param maxsz Size of the largest blocks in the pool (in bytes).
* @param nmax Number of maximum sized blocks in the pool.
* @param align Alignment of the pool's buffer (power of 2).
* @param section Destination binary section for pool data
*/
#define SYS_MEM_POOL_DEFINE(name, kmutex, minsz, maxsz, nmax, align, section) \
char __aligned(align) _GENERIC_SECTION(section) \
_mpool_buf_##name[_ALIGN4(maxsz * nmax) \
+ _MPOOL_BITS_SIZE(maxsz, minsz, nmax)]; \
struct sys_mem_pool_lvl _GENERIC_SECTION(section) \
_mpool_lvls_##name[_MPOOL_LVLS(maxsz, minsz)]; \
_GENERIC_SECTION(section) struct sys_mem_pool name = { \
.base = { \
.buf = _mpool_buf_##name, \
.max_sz = maxsz, \
.n_max = nmax, \
.n_levels = _MPOOL_LVLS(maxsz, minsz), \
.levels = _mpool_lvls_##name, \
.flags = SYS_MEM_POOL_KERNEL \
}, \
.mutex = kmutex, \
}
/**
* @brief Initialize a memory pool
*
* This is intended to complete initialization of memory pools that have been
* declared with SYS_MEM_POOL_DEFINE().
*
* @param p Memory pool to initialize
*/
static inline void sys_mem_pool_init(struct sys_mem_pool *p)
{
_sys_mem_pool_base_init(&p->base);
}
/**
* @brief Allocate a block of memory
*
* Allocate a chunk of memory from a memory pool. This cannot be called from
* interrupt context.
*
* @param p Address of the memory pool
* @param size Requested size of the memory block
* @return A pointer to the requested memory, or NULL if none is available
*/
void *sys_mem_pool_alloc(struct sys_mem_pool *p, size_t size);
/**
* @brief Free memory allocated from a memory pool
*
* Free memory previously allocated by sys_mem_pool_alloc().
* It is safe to pass NULL to this function, in which case it is a no-op.
*
* @param ptr Pointer to previously allocated memory
*/
void sys_mem_pool_free(void *ptr);
#endif