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Christoph Lameter81819f02007-05-06 14:49:36 -07001#ifndef _LINUX_SLUB_DEF_H
2#define _LINUX_SLUB_DEF_H
3
4/*
5 * SLUB : A Slab allocator without object queues.
6 *
7 * (C) 2007 SGI, Christoph Lameter <clameter@sgi.com>
8 */
9#include <linux/types.h>
10#include <linux/gfp.h>
11#include <linux/workqueue.h>
12#include <linux/kobject.h>
13
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080014enum stat_item {
15 ALLOC_FASTPATH, /* Allocation from cpu slab */
16 ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */
17 FREE_FASTPATH, /* Free to cpu slub */
18 FREE_SLOWPATH, /* Freeing not to cpu slab */
19 FREE_FROZEN, /* Freeing to frozen slab */
20 FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */
21 FREE_REMOVE_PARTIAL, /* Freeing removes last object */
22 ALLOC_FROM_PARTIAL, /* Cpu slab acquired from partial list */
23 ALLOC_SLAB, /* Cpu slab acquired from page allocator */
24 ALLOC_REFILL, /* Refill cpu slab from slab freelist */
25 FREE_SLAB, /* Slab freed to the page allocator */
26 CPUSLAB_FLUSH, /* Abandoning of the cpu slab */
27 DEACTIVATE_FULL, /* Cpu slab was full when deactivated */
28 DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */
29 DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */
30 DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */
31 DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
Christoph Lameter65c33762008-04-14 19:11:40 +030032 ORDER_FALLBACK, /* Number of times fallback was necessary */
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080033 NR_SLUB_STAT_ITEMS };
34
Christoph Lameterdfb4f092007-10-16 01:26:05 -070035struct kmem_cache_cpu {
Christoph Lameterda89b792008-01-07 23:20:31 -080036 void **freelist; /* Pointer to first free per cpu object */
37 struct page *page; /* The slab from which we are allocating */
38 int node; /* The node of the page (or -1 for debug) */
39 unsigned int offset; /* Freepointer offset (in word units) */
40 unsigned int objsize; /* Size of an object (from kmem_cache) */
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080041#ifdef CONFIG_SLUB_STATS
42 unsigned stat[NR_SLUB_STAT_ITEMS];
43#endif
Christoph Lameter4c93c3552007-10-16 01:26:08 -070044};
Christoph Lameterdfb4f092007-10-16 01:26:05 -070045
Christoph Lameter81819f02007-05-06 14:49:36 -070046struct kmem_cache_node {
47 spinlock_t list_lock; /* Protect partial list and nr_partial */
48 unsigned long nr_partial;
Christoph Lameter81819f02007-05-06 14:49:36 -070049 struct list_head partial;
Christoph Lameter0c710012007-07-17 04:03:24 -070050#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter0f389ec2008-04-14 18:53:02 +030051 atomic_long_t nr_slabs;
Christoph Lameter205ab992008-04-14 19:11:40 +030052 atomic_long_t total_objects;
Christoph Lameter643b1132007-05-06 14:49:42 -070053 struct list_head full;
Christoph Lameter0c710012007-07-17 04:03:24 -070054#endif
Christoph Lameter81819f02007-05-06 14:49:36 -070055};
56
57/*
Christoph Lameter834f3d12008-04-14 19:11:31 +030058 * Word size structure that can be atomically updated or read and that
59 * contains both the order and the number of objects that a slab of the
60 * given order would contain.
61 */
62struct kmem_cache_order_objects {
63 unsigned long x;
64};
65
66/*
Christoph Lameter81819f02007-05-06 14:49:36 -070067 * Slab cache management.
68 */
69struct kmem_cache {
70 /* Used for retriving partial slabs etc */
71 unsigned long flags;
72 int size; /* The size of an object including meta data */
73 int objsize; /* The size of an object without meta data */
74 int offset; /* Free pointer offset. */
Christoph Lameter834f3d12008-04-14 19:11:31 +030075 struct kmem_cache_order_objects oo;
Christoph Lameter81819f02007-05-06 14:49:36 -070076
77 /*
78 * Avoid an extra cache line for UP, SMP and for the node local to
79 * struct kmem_cache.
80 */
81 struct kmem_cache_node local_node;
82
83 /* Allocation and freeing of slabs */
Christoph Lameter205ab992008-04-14 19:11:40 +030084 struct kmem_cache_order_objects max;
Christoph Lameter65c33762008-04-14 19:11:40 +030085 struct kmem_cache_order_objects min;
Christoph Lameterb7a49f02008-02-14 14:21:32 -080086 gfp_t allocflags; /* gfp flags to use on each alloc */
Christoph Lameter81819f02007-05-06 14:49:36 -070087 int refcount; /* Refcount for slab cache destroy */
Christoph Lameter4ba9b9d2007-10-16 23:25:51 -070088 void (*ctor)(struct kmem_cache *, void *);
Christoph Lameter81819f02007-05-06 14:49:36 -070089 int inuse; /* Offset to metadata */
90 int align; /* Alignment */
91 const char *name; /* Name (only for display!) */
92 struct list_head list; /* List of slab caches */
Christoph Lameter0c710012007-07-17 04:03:24 -070093#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -070094 struct kobject kobj; /* For sysfs */
Christoph Lameter0c710012007-07-17 04:03:24 -070095#endif
Christoph Lameter81819f02007-05-06 14:49:36 -070096
97#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -080098 /*
99 * Defragmentation by allocating from a remote node.
100 */
101 int remote_node_defrag_ratio;
Christoph Lameter81819f02007-05-06 14:49:36 -0700102 struct kmem_cache_node *node[MAX_NUMNODES];
103#endif
Christoph Lameter4c93c3552007-10-16 01:26:08 -0700104#ifdef CONFIG_SMP
105 struct kmem_cache_cpu *cpu_slab[NR_CPUS];
106#else
107 struct kmem_cache_cpu cpu_slab;
108#endif
Christoph Lameter81819f02007-05-06 14:49:36 -0700109};
110
111/*
112 * Kmalloc subsystem.
113 */
Christoph Lameter4b356be2007-06-16 10:16:13 -0700114#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
115#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
116#else
117#define KMALLOC_MIN_SIZE 8
118#endif
119
120#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700121
Christoph Lameter81819f02007-05-06 14:49:36 -0700122/*
123 * We keep the general caches in an array of slab caches that are used for
124 * 2^x bytes of allocations.
125 */
Christoph Lameter331dc552008-02-14 14:28:09 -0800126extern struct kmem_cache kmalloc_caches[PAGE_SHIFT + 1];
Christoph Lameter81819f02007-05-06 14:49:36 -0700127
128/*
129 * Sorry that the following has to be that ugly but some versions of GCC
130 * have trouble with constant propagation and loops.
131 */
Christoph Lameteraa137f92007-08-31 00:48:45 -0700132static __always_inline int kmalloc_index(size_t size)
Christoph Lameter81819f02007-05-06 14:49:36 -0700133{
Christoph Lameter272c1d22007-06-08 13:46:49 -0700134 if (!size)
135 return 0;
Christoph Lameter614410d2007-05-06 14:49:38 -0700136
Christoph Lameter4b356be2007-06-16 10:16:13 -0700137 if (size <= KMALLOC_MIN_SIZE)
138 return KMALLOC_SHIFT_LOW;
139
Christoph Lameter81819f02007-05-06 14:49:36 -0700140 if (size > 64 && size <= 96)
141 return 1;
142 if (size > 128 && size <= 192)
143 return 2;
144 if (size <= 8) return 3;
145 if (size <= 16) return 4;
146 if (size <= 32) return 5;
147 if (size <= 64) return 6;
148 if (size <= 128) return 7;
149 if (size <= 256) return 8;
150 if (size <= 512) return 9;
151 if (size <= 1024) return 10;
152 if (size <= 2 * 1024) return 11;
Christoph Lameter6446faa2008-02-15 23:45:26 -0800153 if (size <= 4 * 1024) return 12;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700154/*
155 * The following is only needed to support architectures with a larger page
156 * size than 4k.
157 */
Christoph Lameter81819f02007-05-06 14:49:36 -0700158 if (size <= 8 * 1024) return 13;
159 if (size <= 16 * 1024) return 14;
160 if (size <= 32 * 1024) return 15;
161 if (size <= 64 * 1024) return 16;
162 if (size <= 128 * 1024) return 17;
163 if (size <= 256 * 1024) return 18;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700164 if (size <= 512 * 1024) return 19;
Christoph Lameter81819f02007-05-06 14:49:36 -0700165 if (size <= 1024 * 1024) return 20;
Christoph Lameter81819f02007-05-06 14:49:36 -0700166 if (size <= 2 * 1024 * 1024) return 21;
Christoph Lameter81819f02007-05-06 14:49:36 -0700167 return -1;
168
169/*
170 * What we really wanted to do and cannot do because of compiler issues is:
171 * int i;
172 * for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
173 * if (size <= (1 << i))
174 * return i;
175 */
176}
177
178/*
179 * Find the slab cache for a given combination of allocation flags and size.
180 *
181 * This ought to end up with a global pointer to the right cache
182 * in kmalloc_caches.
183 */
Christoph Lameteraa137f92007-08-31 00:48:45 -0700184static __always_inline struct kmem_cache *kmalloc_slab(size_t size)
Christoph Lameter81819f02007-05-06 14:49:36 -0700185{
186 int index = kmalloc_index(size);
187
188 if (index == 0)
189 return NULL;
190
Christoph Lameter81819f02007-05-06 14:49:36 -0700191 return &kmalloc_caches[index];
192}
193
194#ifdef CONFIG_ZONE_DMA
195#define SLUB_DMA __GFP_DMA
196#else
197/* Disable DMA functionality */
Al Virod0469432007-07-20 16:18:06 +0100198#define SLUB_DMA (__force gfp_t)0
Christoph Lameter81819f02007-05-06 14:49:36 -0700199#endif
200
Paul Mundt6193a2f2007-07-15 23:38:22 -0700201void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
202void *__kmalloc(size_t size, gfp_t flags);
203
Pekka Enbergeada35e2008-02-11 22:47:46 +0200204static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
205{
206 return (void *)__get_free_pages(flags | __GFP_COMP, get_order(size));
207}
208
Christoph Lameteraa137f92007-08-31 00:48:45 -0700209static __always_inline void *kmalloc(size_t size, gfp_t flags)
Christoph Lameter81819f02007-05-06 14:49:36 -0700210{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700211 if (__builtin_constant_p(size)) {
Christoph Lameter331dc552008-02-14 14:28:09 -0800212 if (size > PAGE_SIZE)
Pekka Enbergeada35e2008-02-11 22:47:46 +0200213 return kmalloc_large(size, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -0700214
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700215 if (!(flags & SLUB_DMA)) {
216 struct kmem_cache *s = kmalloc_slab(size);
Christoph Lameter81819f02007-05-06 14:49:36 -0700217
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700218 if (!s)
219 return ZERO_SIZE_PTR;
220
221 return kmem_cache_alloc(s, flags);
222 }
223 }
224 return __kmalloc(size, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -0700225}
226
Christoph Lameter81819f02007-05-06 14:49:36 -0700227#ifdef CONFIG_NUMA
Paul Mundt6193a2f2007-07-15 23:38:22 -0700228void *__kmalloc_node(size_t size, gfp_t flags, int node);
229void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
Christoph Lameter81819f02007-05-06 14:49:36 -0700230
Christoph Lameteraa137f92007-08-31 00:48:45 -0700231static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
Christoph Lameter81819f02007-05-06 14:49:36 -0700232{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700233 if (__builtin_constant_p(size) &&
Christoph Lameter331dc552008-02-14 14:28:09 -0800234 size <= PAGE_SIZE && !(flags & SLUB_DMA)) {
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700235 struct kmem_cache *s = kmalloc_slab(size);
Christoph Lameter81819f02007-05-06 14:49:36 -0700236
237 if (!s)
Christoph Lameter272c1d22007-06-08 13:46:49 -0700238 return ZERO_SIZE_PTR;
Christoph Lameter81819f02007-05-06 14:49:36 -0700239
240 return kmem_cache_alloc_node(s, flags, node);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700241 }
242 return __kmalloc_node(size, flags, node);
Christoph Lameter81819f02007-05-06 14:49:36 -0700243}
244#endif
245
Christoph Lameter81819f02007-05-06 14:49:36 -0700246#endif /* _LINUX_SLUB_DEF_H */