incubator-nuttx/mm/mm_heap/mm_malloc.c

276 lines
7.4 KiB
C

/****************************************************************************
* mm/mm_heap/mm_malloc.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <debug.h>
#include <string.h>
#include <malloc.h>
#include <nuttx/arch.h>
#include <nuttx/mm/mm.h>
#include <nuttx/sched.h>
#include "mm_heap/mm.h"
#include "kasan/kasan.h"
/****************************************************************************
* Private Functions
****************************************************************************/
static void mm_free_delaylist(FAR struct mm_heap_s *heap)
{
#if defined(CONFIG_BUILD_FLAT) || defined(__KERNEL__)
FAR struct mm_delaynode_s *tmp;
irqstate_t flags;
/* Move the delay list to local */
flags = enter_critical_section();
tmp = heap->mm_delaylist[up_cpu_index()];
heap->mm_delaylist[up_cpu_index()] = NULL;
leave_critical_section(flags);
/* Test if the delayed is empty */
while (tmp)
{
FAR void *address;
/* Get the first delayed deallocation */
address = tmp;
tmp = tmp->flink;
/* The address should always be non-NULL since that was checked in the
* 'while' condition above.
*/
mm_free(heap, address);
}
#endif
}
#if CONFIG_MM_BACKTRACE >= 0
void mm_dump_handler(FAR struct tcb_s *tcb, FAR void *arg)
{
struct mallinfo_task info;
info.pid = tcb->pid;
mm_mallinfo_task(arg, &info);
mwarn("pid:%5d, used:%10d, nused:%10d\n",
tcb->pid, info.uordblks, info.aordblks);
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mm_malloc
*
* Description:
* Find the smallest chunk that satisfies the request. Take the memory from
* that chunk, save the remaining, smaller chunk (if any).
*
* 8-byte alignment of the allocated data is assured.
*
****************************************************************************/
FAR void *mm_malloc(FAR struct mm_heap_s *heap, size_t size)
{
FAR struct mm_freenode_s *node;
size_t alignsize;
FAR void *ret = NULL;
int ndx;
bool val;
/* Free the delay list first */
mm_free_delaylist(heap);
/* Ignore zero-length allocations */
if (size < 1)
{
return NULL;
}
/* Adjust the size to account for (1) the size of the allocated node and
* (2) to make sure that it is an even multiple of our granule size.
*/
alignsize = MM_ALIGN_UP(size + SIZEOF_MM_ALLOCNODE);
if (alignsize < size)
{
/* There must have been an integer overflow */
return NULL;
}
DEBUGASSERT(alignsize >= MM_MIN_CHUNK);
DEBUGASSERT(alignsize >= SIZEOF_MM_FREENODE);
/* We need to hold the MM mutex while we muck with the nodelist. */
val = mm_lock(heap);
DEBUGASSERT(val);
/* Get the location in the node list to start the search. Special case
* really big allocations
*/
if (alignsize >= MM_MAX_CHUNK)
{
ndx = MM_NNODES - 1;
}
else
{
/* Convert the request size into a nodelist index */
ndx = mm_size2ndx(alignsize);
}
/* Search for a large enough chunk in the list of nodes. This list is
* ordered by size, but will have occasional zero sized nodes as we visit
* other mm_nodelist[] entries.
*/
for (node = heap->mm_nodelist[ndx].flink;
node && node->size < alignsize;
node = node->flink)
{
DEBUGASSERT(node->blink->flink == node);
}
/* If we found a node with non-zero size, then this is one to use. Since
* the list is ordered, we know that it must be the best fitting chunk
* available.
*/
if (node)
{
FAR struct mm_freenode_s *remainder;
FAR struct mm_freenode_s *next;
size_t remaining;
/* Remove the node. There must be a predecessor, but there may not be
* a successor node.
*/
DEBUGASSERT(node->blink);
node->blink->flink = node->flink;
if (node->flink)
{
node->flink->blink = node->blink;
}
/* Check if we have to split the free node into one of the allocated
* size and another smaller freenode. In some cases, the remaining
* bytes can be smaller (they may be SIZEOF_MM_ALLOCNODE). In that
* case, we will just carry the few wasted bytes at the end of the
* allocation.
*/
remaining = node->size - alignsize;
if (remaining >= SIZEOF_MM_FREENODE)
{
/* Get a pointer to the next node in physical memory */
next = (FAR struct mm_freenode_s *)
(((FAR char *)node) + node->size);
/* Create the remainder node */
remainder = (FAR struct mm_freenode_s *)
(((FAR char *)node) + alignsize);
remainder->size = remaining;
remainder->preceding = alignsize;
/* Adjust the size of the node under consideration */
node->size = alignsize;
/* Adjust the 'preceding' size of the (old) next node, preserving
* the allocated flag.
*/
next->preceding = remaining | (next->preceding & MM_ALLOC_BIT);
/* Add the remainder back into the nodelist */
mm_addfreechunk(heap, remainder);
}
/* Handle the case of an exact size match */
node->preceding |= MM_ALLOC_BIT;
ret = (FAR void *)((FAR char *)node + SIZEOF_MM_ALLOCNODE);
}
DEBUGASSERT(ret == NULL || mm_heapmember(heap, ret));
mm_unlock(heap);
if (ret)
{
MM_ADD_BACKTRACE(heap, node);
kasan_unpoison(ret, mm_malloc_size(ret));
#ifdef CONFIG_MM_FILL_ALLOCATIONS
memset(ret, 0xaa, alignsize - SIZEOF_MM_ALLOCNODE);
#endif
#ifdef CONFIG_DEBUG_MM
minfo("Allocated %p, size %zu\n", ret, alignsize);
#endif
}
#ifdef CONFIG_DEBUG_MM
else
{
#ifdef CONFIG_MM_DUMP_ON_FAILURE
struct mallinfo minfo;
#endif
mwarn("WARNING: Allocation failed, size %zu\n", alignsize);
#ifdef CONFIG_MM_DUMP_ON_FAILURE
mm_mallinfo(heap, &minfo);
mwarn("Total:%d, used:%d, free:%d, largest:%d, nused:%d, nfree:%d\n",
minfo.arena, minfo.uordblks, minfo.fordblks,
minfo.mxordblk, minfo.aordblks, minfo.ordblks);
# if CONFIG_MM_BACKTRACE >= 0
nxsched_foreach(mm_dump_handler, heap);
# endif
#endif
#ifdef CONFIG_MM_PANIC_ON_FAILURE
PANIC();
#endif
}
#endif
return ret;
}