2 * KERN_SLABALLOC.H - Kernel SLAB memory allocator
4 * Copyright (c) 2003 Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * $DragonFly: src/sys/sys/slaballoc.h,v 1.3 2003/08/28 17:24:36 dillon Exp $
31 #ifndef _SYS_SLABALLOC_H_
32 #define _SYS_SLABALLOC_H_
34 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
36 #ifndef _SYS_MALLOC_H_
37 #include <sys/malloc.h>
41 * Note that any allocations which are exact multiples of PAGE_SIZE, or
42 * which are >= ZALLOC_ZONE_LIMIT, will fall through to the kmem subsystem.
44 #define ZALLOC_ZONE_LIMIT (16 * 1024) /* max slab-managed alloc */
45 #define ZALLOC_MIN_ZONE_SIZE (32 * 1024) /* minimum zone size */
46 #define ZALLOC_MAX_ZONE_SIZE (128 * 1024) /* maximum zone size */
47 #define ZALLOC_SLAB_MAGIC 0x736c6162 /* magic sanity */
48 #define ZALLOC_SLAB_SLIDE 20
51 #if ZALLOC_ZONE_LIMIT == 16384
53 #elif ZALLOC_ZONE_LIMIT == 32768
56 #error "I couldn't figure out NZONES"
60 * Chunk structure for free elements
62 typedef struct SLChunk {
63 struct SLChunk *c_Next;
67 * The IN-BAND zone header is placed at the beginning of each zone.
69 typedef struct SLZone {
70 int32_t z_Magic; /* magic number for sanity check */
71 int z_Cpu; /* which cpu owns this zone? */
72 int z_NFree; /* total free chunks / ualloc space in zone */
73 struct SLZone *z_Next; /* ZoneAry[] link if z_NFree non-zero */
74 int z_NMax; /* maximum free chunks */
75 char *z_BasePtr; /* pointer to start of chunk array */
76 int z_UIndex; /* current initial allocation index */
77 int z_UEndIndex; /* last (first) allocation index */
78 int z_ChunkSize; /* chunk size for validation */
79 int z_FirstFreePg; /* chunk list on a page-by-page basis */
82 SLChunk *z_PageAry[ZALLOC_MAX_ZONE_SIZE / PAGE_SIZE];
85 #define SLZF_UNOTZEROD 0x0001
87 typedef struct SLGlobalData {
88 SLZone *ZoneAry[NZONES]; /* linked list of zones NFree > 0 */
89 SLZone *FreeZones; /* whole zones that have become free */
90 int NFreeZones; /* free zone count */
92 struct malloc_type ZoneInfo; /* stats on meta-zones allocated */
100 void *slab_alloc(struct malloc_type *info, uintptr_t bytes, int flags);
101 void slab_free(void *ptr, struct malloc_type *info);