nuttx/mm/mm_heap/mm.h
2022-04-11 12:46:17 +08:00

277 lines
8.7 KiB
C

/****************************************************************************
* mm/mm_heap/mm.h
*
* 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.
*
****************************************************************************/
#ifndef __MM_MM_HEAP_MM_H
#define __MM_MM_HEAP_MM_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/fs/procfs.h>
#include <assert.h>
#include <execinfo.h>
#include <sys/types.h>
#include <stdbool.h>
#include <string.h>
#include <semaphore.h>
#include <unistd.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Chunk Header Definitions *************************************************/
/* These definitions define the characteristics of the allocator:
*
* MM_MIN_SHIFT is used to define MM_MIN_CHUNK.
* MM_MIN_CHUNK - is the smallest physical chunk that can be allocated.
* It must be at least as large as sizeof(struct mm_freenode_s). Larger
* values may improve performance slightly, but will waste memory due to
* quantization losses.
*
* MM_MAX_SHIFT is used to define MM_MAX_CHUNK
* MM_MAX_CHUNK is the largest, contiguous chunk of memory that can be
* allocated. It can range from 16-bytes to 4Gb. Larger values of
* MM_MAX_SHIFT can cause larger data structure sizes and, perhaps,
* minor performance losses.
*/
#if defined(CONFIG_MM_SMALL) && UINTPTR_MAX <= UINT32_MAX
/* Two byte offsets; Pointers may be 2 or 4 bytes;
* sizeof(struct mm_freenode_s) is 8 or 12 bytes.
* REVISIT: We could do better on machines with 16-bit addressing.
*/
# define MM_MIN_SHIFT_ ( 4) /* 16 bytes */
# define MM_MAX_SHIFT (15) /* 32 Kb */
#elif defined(CONFIG_HAVE_LONG_LONG)
/* Four byte offsets; Pointers may be 4 or 8 bytes
* sizeof(struct mm_freenode_s) is 16 or 24 bytes.
*/
# if UINTPTR_MAX <= UINT32_MAX
# define MM_MIN_SHIFT_ ( 4) /* 16 bytes */
# elif UINTPTR_MAX <= UINT64_MAX
# define MM_MIN_SHIFT_ ( 5) /* 32 bytes */
# endif
# define MM_MAX_SHIFT (22) /* 4 Mb */
#else
/* Four byte offsets; Pointers must be 4 bytes.
* sizeof(struct mm_freenode_s) is 16 bytes.
*/
# define MM_MIN_SHIFT_ ( 4) /* 16 bytes */
# define MM_MAX_SHIFT (22) /* 4 Mb */
#endif
#ifdef CONFIG_DEBUG_MM
# define MM_MIN_SHIFT (MM_MIN_SHIFT_ + 2)
# define MM_BACKTRACE_DEPTH 8
# define MM_ADD_BACKTRACE(heap, ptr) \
do \
{ \
FAR struct mm_allocnode_s *tmp = (FAR struct mm_allocnode_s *)(ptr); \
tmp->pid = getpid(); \
if ((heap)->mm_procfs.backtrace) \
{ \
memset(tmp->backtrace, 0, sizeof(tmp->backtrace)); \
backtrace(tmp->backtrace, MM_BACKTRACE_DEPTH); \
} \
else \
{ \
tmp->backtrace[0] = 0; \
} \
} \
while (0)
#else
# define MM_ADD_BACKTRACE(heap, ptr)
# define MM_MIN_SHIFT MM_MIN_SHIFT_
#endif
/* All other definitions derive from these two */
#define MM_MIN_CHUNK (1 << MM_MIN_SHIFT)
#define MM_MAX_CHUNK (1 << MM_MAX_SHIFT)
#define MM_NNODES (MM_MAX_SHIFT - MM_MIN_SHIFT + 1)
#define MM_GRAN_MASK (MM_MIN_CHUNK - 1)
#define MM_ALIGN_UP(a) (((a) + MM_GRAN_MASK) & ~MM_GRAN_MASK)
#define MM_ALIGN_DOWN(a) ((a) & ~MM_GRAN_MASK)
/* An allocated chunk is distinguished from a free chunk by bit 0
* of the 'preceding' chunk size. If set, then this is an allocated chunk.
*/
#define MM_ALLOC_BIT 0x1
#ifdef CONFIG_MM_SMALL
# define MMSIZE_MAX UINT16_MAX
#else
# define MMSIZE_MAX UINT32_MAX
#endif
#define MM_IS_ALLOCATED(n) \
((int)((FAR struct mm_allocnode_s *)(n)->preceding) < 0)
/* What is the size of the allocnode? */
#define SIZEOF_MM_ALLOCNODE sizeof(struct mm_allocnode_s)
/* What is the size of the freenode? */
#define SIZEOF_MM_FREENODE sizeof(struct mm_freenode_s)
/****************************************************************************
* Public Types
****************************************************************************/
/* Determines the size of the chunk size/offset type */
#ifdef CONFIG_MM_SMALL
typedef uint16_t mmsize_t;
#else
typedef uint32_t mmsize_t;
#endif
/* This describes an allocated chunk. An allocated chunk is
* distinguished from a free chunk by bit 15/31 of the 'preceding' chunk
* size. If set, then this is an allocated chunk.
*/
struct mm_allocnode_s
{
#ifdef CONFIG_DEBUG_MM
pid_t pid; /* The pid for caller */
FAR void *backtrace[MM_BACKTRACE_DEPTH]; /* The backtrace buffer for caller */
#endif
mmsize_t size; /* Size of this chunk */
mmsize_t preceding; /* Size of the preceding chunk */
};
static_assert(SIZEOF_MM_ALLOCNODE <= MM_MIN_CHUNK,
"Error size for struct mm_allocnode_s\n");
/* This describes a free chunk */
struct mm_freenode_s
{
#ifdef CONFIG_DEBUG_MM
pid_t pid; /* The pid for caller */
FAR void *backtrace[MM_BACKTRACE_DEPTH]; /* The backtrace buffer for caller */
#endif
mmsize_t size; /* Size of this chunk */
mmsize_t preceding; /* Size of the preceding chunk */
FAR struct mm_freenode_s *flink; /* Supports a doubly linked list */
FAR struct mm_freenode_s *blink;
};
static_assert(SIZEOF_MM_FREENODE <= MM_MIN_CHUNK,
"Error size for struct mm_freenode_s\n");
struct mm_delaynode_s
{
FAR struct mm_delaynode_s *flink;
};
/* This describes one heap (possibly with multiple regions) */
struct mm_heap_s
{
/* Mutually exclusive access to this data set is enforced with
* the following un-named semaphore.
*/
sem_t mm_semaphore;
/* This is the size of the heap provided to mm */
size_t mm_heapsize;
/* This is the first and last nodes of the heap */
FAR struct mm_allocnode_s *mm_heapstart[CONFIG_MM_REGIONS];
FAR struct mm_allocnode_s *mm_heapend[CONFIG_MM_REGIONS];
#if CONFIG_MM_REGIONS > 1
int mm_nregions;
#endif
/* All free nodes are maintained in a doubly linked list. This
* array provides some hooks into the list at various points to
* speed searches for free nodes.
*/
struct mm_freenode_s mm_nodelist[MM_NNODES];
/* Free delay list, for some situations where we can't do free
* immdiately.
*/
FAR struct mm_delaynode_s *mm_delaylist[CONFIG_SMP_NCPUS];
#if defined(CONFIG_FS_PROCFS) && !defined(CONFIG_FS_PROCFS_EXCLUDE_MEMINFO)
struct procfs_meminfo_entry_s mm_procfs;
#endif
};
/* This describes the callback for mm_foreach */
typedef CODE void (*mmchunk_handler_t)(FAR struct mm_allocnode_s *node,
FAR void *arg);
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/* Functions contained in mm_sem.c ******************************************/
void mm_seminitialize(FAR struct mm_heap_s *heap);
bool mm_takesemaphore(FAR struct mm_heap_s *heap);
void mm_givesemaphore(FAR struct mm_heap_s *heap);
/* Functions contained in mm_shrinkchunk.c **********************************/
void mm_shrinkchunk(FAR struct mm_heap_s *heap,
FAR struct mm_allocnode_s *node, size_t size);
/* Functions contained in mm_addfreechunk.c *********************************/
void mm_addfreechunk(FAR struct mm_heap_s *heap,
FAR struct mm_freenode_s *node);
/* Functions contained in mm_size2ndx.c *************************************/
int mm_size2ndx(size_t size);
/* Functions contained in mm_foreach.c **************************************/
void mm_foreach(FAR struct mm_heap_s *heap, mmchunk_handler_t handler,
FAR void *arg);
#endif /* __MM_MM_HEAP_MM_H */