297 lines
9.7 KiB
C
297 lines
9.7 KiB
C
|
/*
|
||
|
|
* File : memheap.c
|
||
|
|
* This file is part of RT-Thread RTOS
|
||
|
|
* COPYRIGHT (C) 2012, RT-Thread Development Team
|
||
|
|
*
|
||
|
|
* The license and distribution terms for this file may be
|
||
|
|
* found in the file LICENSE in this distribution or at
|
||
|
|
* http://www.rt-thread.org/license/LICENSE
|
||
|
|
*
|
||
|
|
* Change Logs:
|
||
|
|
* Date Author Notes
|
||
|
|
* 2012-04-10 Bernard first implementation
|
||
|
|
*/
|
||
|
|
#include <rtthread.h>
|
||
|
|
|
||
|
|
#ifdef RT_USING_MEMHEAP
|
||
|
|
|
||
|
|
/* dynamic pool magic and mask */
|
||
|
|
#define RT_MEMHEAP_MAGIC 0x1ea01ea0
|
||
|
|
#define RT_MEMHEAP_MASK 0xfffffffe
|
||
|
|
#define RT_MEMHEAP_USED 0x01
|
||
|
|
#define RT_MEMHEAP_FREED 0x00
|
||
|
|
|
||
|
|
#define RT_MEMHEAP_IS_USED(i) ((i)->magic & RT_MEMHEAP_USED)
|
||
|
|
#define RT_MEMHEAP_MINIALLOC 12
|
||
|
|
|
||
|
|
#define RT_MEMHEAP_SIZE RT_ALIGN(sizeof(struct rt_memheap_item), RT_ALIGN_SIZE)
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The initialized memory pool will be:
|
||
|
|
* +-----------------------------------+--------------------------+
|
||
|
|
* | whole freed memory block | Used Memory Block Tailer |
|
||
|
|
* +-----------------------------------+--------------------------+
|
||
|
|
*
|
||
|
|
* block_list --> whole freed memory block
|
||
|
|
*
|
||
|
|
* The length of Used Memory Block Tailer is 0, which is prevents block merging across list
|
||
|
|
*/
|
||
|
|
rt_err_t rt_memheap_init(struct rt_memheap* memheap, const char* name,
|
||
|
|
void *start_addr,
|
||
|
|
rt_uint32_t size)
|
||
|
|
{
|
||
|
|
struct rt_memheap_item *item;
|
||
|
|
|
||
|
|
RT_ASSERT(memheap != RT_NULL);
|
||
|
|
|
||
|
|
/* initialize pool object */
|
||
|
|
rt_object_init(&(memheap->parent), RT_Object_Class_MemHeap, name);
|
||
|
|
|
||
|
|
memheap->start_addr = start_addr;
|
||
|
|
memheap->pool_size = RT_ALIGN_DOWN(size, RT_ALIGN_SIZE);
|
||
|
|
memheap->available_size = memheap->pool_size - (2 * RT_MEMHEAP_SIZE);
|
||
|
|
|
||
|
|
/* initialize the free list header */
|
||
|
|
item = &(memheap->free_header);
|
||
|
|
item->magic = RT_MEMHEAP_MAGIC;
|
||
|
|
item->pool_ptr = memheap;
|
||
|
|
item->next = RT_NULL;
|
||
|
|
item->prev = RT_NULL;
|
||
|
|
item->next_free = item;
|
||
|
|
item->prev_free = item;
|
||
|
|
|
||
|
|
/* set the free list to free list header */
|
||
|
|
memheap->free_list = item;
|
||
|
|
|
||
|
|
/* initialize the first big memory block */
|
||
|
|
item = (struct rt_memheap_item*) start_addr;
|
||
|
|
item->magic = RT_MEMHEAP_MAGIC;
|
||
|
|
item->pool_ptr = memheap;
|
||
|
|
item->next = RT_NULL;
|
||
|
|
item->prev = RT_NULL;
|
||
|
|
item->next_free = item;
|
||
|
|
item->prev_free = item;
|
||
|
|
|
||
|
|
item->next = (struct rt_memheap_item *)
|
||
|
|
((rt_uint8_t*) item + memheap->available_size + RT_MEMHEAP_SIZE);
|
||
|
|
item->prev = item->next;
|
||
|
|
|
||
|
|
/* block list header */
|
||
|
|
memheap->block_list = item;
|
||
|
|
|
||
|
|
/* place the big memory block to free list */
|
||
|
|
item->next_free = memheap->free_list->next_free;
|
||
|
|
item->prev_free = memheap->free_list;
|
||
|
|
memheap->free_list->next_free->prev_free = item;
|
||
|
|
memheap->free_list->next_free = item;
|
||
|
|
|
||
|
|
/* move to the end of memory pool to build a small tailer block, which prevents block merging */
|
||
|
|
item = item->next;
|
||
|
|
/* it's a used memory block */
|
||
|
|
item->magic = RT_MEMHEAP_MAGIC | RT_MEMHEAP_USED;
|
||
|
|
item->pool_ptr = memheap;
|
||
|
|
item->next = (struct rt_memheap_item *) start_addr;
|
||
|
|
item->prev = (struct rt_memheap_item *) start_addr;
|
||
|
|
/* not in free list */
|
||
|
|
item->next_free = item->prev_free = RT_NULL;
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("memory heap: start addr 0x%08x, size %d, free list header 0x%08x",
|
||
|
|
start_addr, size, &(memheap->free_header)));
|
||
|
|
|
||
|
|
return RT_EOK;
|
||
|
|
}
|
||
|
|
|
||
|
|
rt_err_t rt_memheap_detach(struct rt_memheap* heap)
|
||
|
|
{
|
||
|
|
rt_object_detach(&(heap->parent));
|
||
|
|
|
||
|
|
/* Return a successful completion. */
|
||
|
|
return RT_EOK;
|
||
|
|
}
|
||
|
|
|
||
|
|
void* rt_memheap_alloc(struct rt_memheap *pool_ptr, rt_uint32_t size)
|
||
|
|
{
|
||
|
|
rt_uint32_t free_size;
|
||
|
|
struct rt_memheap_item *header_ptr;
|
||
|
|
|
||
|
|
RT_ASSERT(pool_ptr != RT_NULL);
|
||
|
|
|
||
|
|
/* align allocated size */
|
||
|
|
size = RT_ALIGN(size, RT_ALIGN_SIZE);
|
||
|
|
if (size < RT_MEMHEAP_MINIALLOC) size = RT_MEMHEAP_MINIALLOC;
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("allocate %d", size));
|
||
|
|
|
||
|
|
if (size < pool_ptr->available_size)
|
||
|
|
{
|
||
|
|
/* search on free list */
|
||
|
|
free_size = 0;
|
||
|
|
/* get the first free memory block */
|
||
|
|
header_ptr = pool_ptr->free_list->next_free;
|
||
|
|
while (header_ptr != pool_ptr->free_list && free_size < size)
|
||
|
|
{
|
||
|
|
/* get current freed memory block size */
|
||
|
|
free_size = (rt_uint32_t)(header_ptr->next) - (rt_uint32_t)header_ptr - RT_MEMHEAP_SIZE;
|
||
|
|
|
||
|
|
if (free_size < size)
|
||
|
|
{
|
||
|
|
/* move to next free memory block */
|
||
|
|
header_ptr = header_ptr->next_free;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* determine if the memory is available. */
|
||
|
|
if (free_size >= size)
|
||
|
|
{
|
||
|
|
/* a block that satisfies the request has been found. */
|
||
|
|
|
||
|
|
/* determine if the block needs to be split. */
|
||
|
|
if (free_size >= (size + RT_MEMHEAP_SIZE + RT_MEMHEAP_MINIALLOC))
|
||
|
|
{
|
||
|
|
struct rt_memheap_item* new_ptr;
|
||
|
|
|
||
|
|
/* split the block. */
|
||
|
|
new_ptr = (struct rt_memheap_item*) (((rt_uint8_t*) header_ptr) + size + RT_MEMHEAP_SIZE);
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("split: h[0x%08x] nm[0x%08x] pm[0x%08x] to n[0x%08x]", header_ptr,
|
||
|
|
header_ptr->next, header_ptr->prev,
|
||
|
|
new_ptr));
|
||
|
|
|
||
|
|
/* mark the new block as a memory block and freed. */
|
||
|
|
new_ptr->magic = RT_MEMHEAP_MAGIC;
|
||
|
|
|
||
|
|
/* put the pool pointer into the new block. */
|
||
|
|
new_ptr->pool_ptr = pool_ptr;
|
||
|
|
|
||
|
|
/* break down the block list */
|
||
|
|
new_ptr->prev = header_ptr;
|
||
|
|
new_ptr->next = header_ptr->next;
|
||
|
|
header_ptr->next->prev = new_ptr;
|
||
|
|
header_ptr->next = new_ptr;
|
||
|
|
|
||
|
|
/* remove header ptr from free list */
|
||
|
|
header_ptr->next_free->prev_free = header_ptr->prev_free;
|
||
|
|
header_ptr->prev_free->next_free = header_ptr->next_free;
|
||
|
|
header_ptr->next_free = RT_NULL;
|
||
|
|
header_ptr->prev_free = RT_NULL;
|
||
|
|
|
||
|
|
/* insert new_ptr to free list */
|
||
|
|
new_ptr->next_free = pool_ptr->free_list->next_free;
|
||
|
|
new_ptr->prev_free = pool_ptr->free_list;
|
||
|
|
pool_ptr->free_list->next_free->prev_free = new_ptr;
|
||
|
|
pool_ptr->free_list->next_free = new_ptr;
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("new ptr: nf 0x%08x, pf 0x%08x",
|
||
|
|
new_ptr->next_free, new_ptr->prev_free));
|
||
|
|
|
||
|
|
/* decrement the available byte count. */
|
||
|
|
pool_ptr->available_size = pool_ptr->available_size - size - RT_MEMHEAP_SIZE;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* decrement the entire free size from the available bytes count. */
|
||
|
|
pool_ptr->available_size = pool_ptr->available_size - free_size;
|
||
|
|
|
||
|
|
/* remove header_ptr from free list */
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("one block: h[0x%08x], nf 0x%08x, pf 0x%08x", header_ptr,
|
||
|
|
header_ptr->next_free, header_ptr->prev_free));
|
||
|
|
|
||
|
|
header_ptr->next_free->prev_free = header_ptr->prev_free;
|
||
|
|
header_ptr->prev_free->next_free = header_ptr->next_free;
|
||
|
|
header_ptr->next_free = RT_NULL;
|
||
|
|
header_ptr->prev_free = RT_NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Mark the allocated block as not available. */
|
||
|
|
header_ptr->magic |= RT_MEMHEAP_USED;
|
||
|
|
|
||
|
|
/* Return a memory address to the caller. */
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("am: m[0x%08x], h[0x%08x], size: %d",
|
||
|
|
(void*) ((rt_uint8_t*)header_ptr + RT_MEMHEAP_SIZE), header_ptr, size);
|
||
|
|
return (void*) ((rt_uint8_t*)header_ptr + RT_MEMHEAP_SIZE));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("allocate memory: failed\n"));
|
||
|
|
|
||
|
|
/* Return the completion status. */
|
||
|
|
return RT_NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
void rt_memheap_free(void* ptr)
|
||
|
|
{
|
||
|
|
struct rt_memheap *pool_ptr;
|
||
|
|
struct rt_memheap_item *header_ptr, *new_ptr;
|
||
|
|
rt_uint32_t insert_header;
|
||
|
|
|
||
|
|
/* set initial status as OK */
|
||
|
|
insert_header = 1; new_ptr = RT_NULL;
|
||
|
|
header_ptr = (struct rt_memheap_item*)((rt_uint8_t*)ptr - RT_MEMHEAP_SIZE);
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("free memory: m[0x%08x], h[0x%08x]", ptr, header_ptr));
|
||
|
|
|
||
|
|
/* check magic */
|
||
|
|
RT_ASSERT((header_ptr->magic & RT_MEMHEAP_MASK) == RT_MEMHEAP_MAGIC);
|
||
|
|
|
||
|
|
/* get pool ptr */
|
||
|
|
pool_ptr = header_ptr->pool_ptr;
|
||
|
|
|
||
|
|
/* Mark the memory as available. */
|
||
|
|
header_ptr->magic &= ~RT_MEMHEAP_USED;
|
||
|
|
|
||
|
|
/* Adjust the available number of bytes. */
|
||
|
|
pool_ptr->available_size = pool_ptr->available_size +
|
||
|
|
((rt_uint32_t)(header_ptr->next) -
|
||
|
|
(rt_uint32_t)header_ptr) - RT_MEMHEAP_SIZE;
|
||
|
|
|
||
|
|
/* Determine if the block can be merged with the previous neighbor. */
|
||
|
|
if (!RT_MEMHEAP_IS_USED(header_ptr->prev))
|
||
|
|
{
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("merge: left node 0x%08x", header_ptr->prev));
|
||
|
|
|
||
|
|
/* adjust the available number of bytes. */
|
||
|
|
pool_ptr->available_size = pool_ptr->available_size + RT_MEMHEAP_SIZE;
|
||
|
|
|
||
|
|
/* yes, merge block with previous neighbor. */
|
||
|
|
(header_ptr->prev)->next = header_ptr->next;
|
||
|
|
(header_ptr->next)->prev = header_ptr->prev;
|
||
|
|
|
||
|
|
/* move header pointer to previous. */
|
||
|
|
header_ptr = header_ptr->prev;
|
||
|
|
insert_header = 0; /* don't insert header to free list */
|
||
|
|
}
|
||
|
|
|
||
|
|
/* determine if the block can be merged with the next neighbor. */
|
||
|
|
if (!RT_MEMHEAP_IS_USED(header_ptr->next))
|
||
|
|
{
|
||
|
|
/* adjust the available number of bytes. */
|
||
|
|
pool_ptr->available_size = pool_ptr->available_size + RT_MEMHEAP_SIZE;
|
||
|
|
|
||
|
|
/* merge block with next neighbor. */
|
||
|
|
new_ptr = header_ptr->next;
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("merge: right node 0x%08x, nf 0x%08x, pf 0x%08x",
|
||
|
|
new_ptr, new_ptr->next_free, new_ptr->prev_free));
|
||
|
|
|
||
|
|
new_ptr->next->prev = header_ptr;
|
||
|
|
header_ptr->next = new_ptr->next;
|
||
|
|
|
||
|
|
/* remove new ptr from free list */
|
||
|
|
new_ptr->next_free->prev_free = new_ptr->prev_free;
|
||
|
|
new_ptr->prev_free->next_free = new_ptr->next_free;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (insert_header)
|
||
|
|
{
|
||
|
|
/* no left merge, insert to free list */
|
||
|
|
header_ptr->next_free = pool_ptr->free_list->next_free;
|
||
|
|
header_ptr->prev_free = pool_ptr->free_list;
|
||
|
|
pool_ptr->free_list->next_free->prev_free = header_ptr;
|
||
|
|
pool_ptr->free_list->next_free = header_ptr;
|
||
|
|
|
||
|
|
RT_DEBUG_LOG(RT_DEBUG_MEMHEAP, ("insert to free list: nf 0x%08x, pf 0x%08x",
|
||
|
|
header_ptr->next_free, header_ptr->prev_free));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|