blob: 5046f90c11710178127a20a7bcb8677b4e80d943 [file] [log] [blame]
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 *
Christoph Lametercde53532008-07-04 09:59:22 -07007 * (C) 2007 SGI, Christoph Lameter
Christoph Lameter81819f02007-05-06 14:49:36 -07008 */
9#include <linux/types.h>
10#include <linux/gfp.h>
11#include <linux/workqueue.h>
12#include <linux/kobject.h>
Frederic Weisbecker36994e52008-12-29 13:42:23 -080013#include <trace/kmemtrace.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070014
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080015enum stat_item {
16 ALLOC_FASTPATH, /* Allocation from cpu slab */
17 ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */
18 FREE_FASTPATH, /* Free to cpu slub */
19 FREE_SLOWPATH, /* Freeing not to cpu slab */
20 FREE_FROZEN, /* Freeing to frozen slab */
21 FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */
22 FREE_REMOVE_PARTIAL, /* Freeing removes last object */
23 ALLOC_FROM_PARTIAL, /* Cpu slab acquired from partial list */
24 ALLOC_SLAB, /* Cpu slab acquired from page allocator */
25 ALLOC_REFILL, /* Refill cpu slab from slab freelist */
26 FREE_SLAB, /* Slab freed to the page allocator */
27 CPUSLAB_FLUSH, /* Abandoning of the cpu slab */
28 DEACTIVATE_FULL, /* Cpu slab was full when deactivated */
29 DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */
30 DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */
31 DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */
32 DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
Christoph Lameter65c33762008-04-14 19:11:40 +030033 ORDER_FALLBACK, /* Number of times fallback was necessary */
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080034 NR_SLUB_STAT_ITEMS };
35
Christoph Lameterdfb4f092007-10-16 01:26:05 -070036struct kmem_cache_cpu {
Christoph Lameterda89b792008-01-07 23:20:31 -080037 void **freelist; /* Pointer to first free per cpu object */
38 struct page *page; /* The slab from which we are allocating */
39 int node; /* The node of the page (or -1 for debug) */
40 unsigned int offset; /* Freepointer offset (in word units) */
41 unsigned int objsize; /* Size of an object (from kmem_cache) */
Christoph Lameter8ff12cf2008-02-07 17:47:41 -080042#ifdef CONFIG_SLUB_STATS
43 unsigned stat[NR_SLUB_STAT_ITEMS];
44#endif
Christoph Lameter4c93c3552007-10-16 01:26:08 -070045};
Christoph Lameterdfb4f092007-10-16 01:26:05 -070046
Christoph Lameter81819f02007-05-06 14:49:36 -070047struct kmem_cache_node {
48 spinlock_t list_lock; /* Protect partial list and nr_partial */
49 unsigned long nr_partial;
Christoph Lameter81819f02007-05-06 14:49:36 -070050 struct list_head partial;
Christoph Lameter0c710012007-07-17 04:03:24 -070051#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter0f389ec2008-04-14 18:53:02 +030052 atomic_long_t nr_slabs;
Christoph Lameter205ab992008-04-14 19:11:40 +030053 atomic_long_t total_objects;
Christoph Lameter643b1132007-05-06 14:49:42 -070054 struct list_head full;
Christoph Lameter0c710012007-07-17 04:03:24 -070055#endif
Christoph Lameter81819f02007-05-06 14:49:36 -070056};
57
58/*
Christoph Lameter834f3d12008-04-14 19:11:31 +030059 * Word size structure that can be atomically updated or read and that
60 * contains both the order and the number of objects that a slab of the
61 * given order would contain.
62 */
63struct kmem_cache_order_objects {
64 unsigned long x;
65};
66
67/*
Christoph Lameter81819f02007-05-06 14:49:36 -070068 * Slab cache management.
69 */
70struct kmem_cache {
71 /* Used for retriving partial slabs etc */
72 unsigned long flags;
73 int size; /* The size of an object including meta data */
74 int objsize; /* The size of an object without meta data */
75 int offset; /* Free pointer offset. */
Christoph Lameter834f3d12008-04-14 19:11:31 +030076 struct kmem_cache_order_objects oo;
Christoph Lameter81819f02007-05-06 14:49:36 -070077
78 /*
79 * Avoid an extra cache line for UP, SMP and for the node local to
80 * struct kmem_cache.
81 */
82 struct kmem_cache_node local_node;
83
84 /* Allocation and freeing of slabs */
Christoph Lameter205ab992008-04-14 19:11:40 +030085 struct kmem_cache_order_objects max;
Christoph Lameter65c33762008-04-14 19:11:40 +030086 struct kmem_cache_order_objects min;
Christoph Lameterb7a49f02008-02-14 14:21:32 -080087 gfp_t allocflags; /* gfp flags to use on each alloc */
Christoph Lameter81819f02007-05-06 14:49:36 -070088 int refcount; /* Refcount for slab cache destroy */
Alexey Dobriyan51cc5062008-07-25 19:45:34 -070089 void (*ctor)(void *);
Christoph Lameter81819f02007-05-06 14:49:36 -070090 int inuse; /* Offset to metadata */
91 int align; /* Alignment */
David Rientjes3b89d7d2009-02-22 17:40:07 -080092 unsigned long min_partial;
Christoph Lameter81819f02007-05-06 14:49:36 -070093 const char *name; /* Name (only for display!) */
94 struct list_head list; /* List of slab caches */
Christoph Lameter0c710012007-07-17 04:03:24 -070095#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -070096 struct kobject kobj; /* For sysfs */
Christoph Lameter0c710012007-07-17 04:03:24 -070097#endif
Christoph Lameter81819f02007-05-06 14:49:36 -070098
99#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -0800100 /*
101 * Defragmentation by allocating from a remote node.
102 */
103 int remote_node_defrag_ratio;
Christoph Lameter81819f02007-05-06 14:49:36 -0700104 struct kmem_cache_node *node[MAX_NUMNODES];
105#endif
Christoph Lameter4c93c3552007-10-16 01:26:08 -0700106#ifdef CONFIG_SMP
107 struct kmem_cache_cpu *cpu_slab[NR_CPUS];
108#else
109 struct kmem_cache_cpu cpu_slab;
110#endif
Christoph Lameter81819f02007-05-06 14:49:36 -0700111};
112
113/*
114 * Kmalloc subsystem.
115 */
Christoph Lameter4b356be2007-06-16 10:16:13 -0700116#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
117#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
118#else
119#define KMALLOC_MIN_SIZE 8
120#endif
121
122#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700123
Christoph Lameter81819f02007-05-06 14:49:36 -0700124/*
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500125 * Maximum kmalloc object size handled by SLUB. Larger object allocations
126 * are passed through to the page allocator. The page allocator "fastpath"
127 * is relatively slow so we need this value sufficiently high so that
128 * performance critical objects are allocated through the SLUB fastpath.
129 *
130 * This should be dropped to PAGE_SIZE / 2 once the page allocator
131 * "fastpath" becomes competitive with the slab allocator fastpaths.
132 */
Pekka Enberg51735a72009-02-20 12:21:33 +0200133#define SLUB_MAX_SIZE (2 * PAGE_SIZE)
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500134
Pekka Enberg51735a72009-02-20 12:21:33 +0200135#define SLUB_PAGE_SHIFT (PAGE_SHIFT + 2)
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500136
137/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700138 * We keep the general caches in an array of slab caches that are used for
139 * 2^x bytes of allocations.
140 */
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500141extern struct kmem_cache kmalloc_caches[SLUB_PAGE_SHIFT];
Christoph Lameter81819f02007-05-06 14:49:36 -0700142
143/*
144 * Sorry that the following has to be that ugly but some versions of GCC
145 * have trouble with constant propagation and loops.
146 */
Christoph Lameteraa137f92007-08-31 00:48:45 -0700147static __always_inline int kmalloc_index(size_t size)
Christoph Lameter81819f02007-05-06 14:49:36 -0700148{
Christoph Lameter272c1d22007-06-08 13:46:49 -0700149 if (!size)
150 return 0;
Christoph Lameter614410d2007-05-06 14:49:38 -0700151
Christoph Lameter4b356be2007-06-16 10:16:13 -0700152 if (size <= KMALLOC_MIN_SIZE)
153 return KMALLOC_SHIFT_LOW;
154
Christoph Lameter41d54d32008-07-03 09:14:26 -0500155#if KMALLOC_MIN_SIZE <= 64
Christoph Lameter81819f02007-05-06 14:49:36 -0700156 if (size > 64 && size <= 96)
157 return 1;
158 if (size > 128 && size <= 192)
159 return 2;
Christoph Lameter41d54d32008-07-03 09:14:26 -0500160#endif
Christoph Lameter81819f02007-05-06 14:49:36 -0700161 if (size <= 8) return 3;
162 if (size <= 16) return 4;
163 if (size <= 32) return 5;
164 if (size <= 64) return 6;
165 if (size <= 128) return 7;
166 if (size <= 256) return 8;
167 if (size <= 512) return 9;
168 if (size <= 1024) return 10;
169 if (size <= 2 * 1024) return 11;
Christoph Lameter6446faa2008-02-15 23:45:26 -0800170 if (size <= 4 * 1024) return 12;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700171/*
172 * The following is only needed to support architectures with a larger page
173 * size than 4k.
174 */
Christoph Lameter81819f02007-05-06 14:49:36 -0700175 if (size <= 8 * 1024) return 13;
176 if (size <= 16 * 1024) return 14;
177 if (size <= 32 * 1024) return 15;
178 if (size <= 64 * 1024) return 16;
179 if (size <= 128 * 1024) return 17;
180 if (size <= 256 * 1024) return 18;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700181 if (size <= 512 * 1024) return 19;
Christoph Lameter81819f02007-05-06 14:49:36 -0700182 if (size <= 1024 * 1024) return 20;
Christoph Lameter81819f02007-05-06 14:49:36 -0700183 if (size <= 2 * 1024 * 1024) return 21;
Christoph Lameter81819f02007-05-06 14:49:36 -0700184 return -1;
185
186/*
187 * What we really wanted to do and cannot do because of compiler issues is:
188 * int i;
189 * for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
190 * if (size <= (1 << i))
191 * return i;
192 */
193}
194
195/*
196 * Find the slab cache for a given combination of allocation flags and size.
197 *
198 * This ought to end up with a global pointer to the right cache
199 * in kmalloc_caches.
200 */
Christoph Lameteraa137f92007-08-31 00:48:45 -0700201static __always_inline struct kmem_cache *kmalloc_slab(size_t size)
Christoph Lameter81819f02007-05-06 14:49:36 -0700202{
203 int index = kmalloc_index(size);
204
205 if (index == 0)
206 return NULL;
207
Christoph Lameter81819f02007-05-06 14:49:36 -0700208 return &kmalloc_caches[index];
209}
210
211#ifdef CONFIG_ZONE_DMA
212#define SLUB_DMA __GFP_DMA
213#else
214/* Disable DMA functionality */
Al Virod0469432007-07-20 16:18:06 +0100215#define SLUB_DMA (__force gfp_t)0
Christoph Lameter81819f02007-05-06 14:49:36 -0700216#endif
217
Paul Mundt6193a2f2007-07-15 23:38:22 -0700218void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
219void *__kmalloc(size_t size, gfp_t flags);
220
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300221#ifdef CONFIG_KMEMTRACE
222extern void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags);
223#else
224static __always_inline void *
225kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
226{
227 return kmem_cache_alloc(s, gfpflags);
228}
229#endif
230
Pekka Enbergeada35e2008-02-11 22:47:46 +0200231static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
232{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300233 unsigned int order = get_order(size);
234 void *ret = (void *) __get_free_pages(flags | __GFP_COMP, order);
235
Eduard - Gabriel Munteanuca2b84c2009-03-23 15:12:24 +0200236 trace_kmalloc(_THIS_IP_, ret, size, PAGE_SIZE << order, flags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300237
238 return ret;
Pekka Enbergeada35e2008-02-11 22:47:46 +0200239}
240
Christoph Lameteraa137f92007-08-31 00:48:45 -0700241static __always_inline void *kmalloc(size_t size, gfp_t flags)
Christoph Lameter81819f02007-05-06 14:49:36 -0700242{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300243 void *ret;
244
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700245 if (__builtin_constant_p(size)) {
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500246 if (size > SLUB_MAX_SIZE)
Pekka Enbergeada35e2008-02-11 22:47:46 +0200247 return kmalloc_large(size, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -0700248
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700249 if (!(flags & SLUB_DMA)) {
250 struct kmem_cache *s = kmalloc_slab(size);
Christoph Lameter81819f02007-05-06 14:49:36 -0700251
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700252 if (!s)
253 return ZERO_SIZE_PTR;
254
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300255 ret = kmem_cache_alloc_notrace(s, flags);
256
Eduard - Gabriel Munteanuca2b84c2009-03-23 15:12:24 +0200257 trace_kmalloc(_THIS_IP_, ret, size, s->size, flags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300258
259 return ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700260 }
261 }
262 return __kmalloc(size, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -0700263}
264
Christoph Lameter81819f02007-05-06 14:49:36 -0700265#ifdef CONFIG_NUMA
Paul Mundt6193a2f2007-07-15 23:38:22 -0700266void *__kmalloc_node(size_t size, gfp_t flags, int node);
267void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
Christoph Lameter81819f02007-05-06 14:49:36 -0700268
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300269#ifdef CONFIG_KMEMTRACE
270extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
271 gfp_t gfpflags,
272 int node);
273#else
274static __always_inline void *
275kmem_cache_alloc_node_notrace(struct kmem_cache *s,
276 gfp_t gfpflags,
277 int node)
278{
279 return kmem_cache_alloc_node(s, gfpflags, node);
280}
281#endif
282
Christoph Lameteraa137f92007-08-31 00:48:45 -0700283static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
Christoph Lameter81819f02007-05-06 14:49:36 -0700284{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300285 void *ret;
286
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700287 if (__builtin_constant_p(size) &&
Christoph Lameterffadd4d2009-02-17 12:05:07 -0500288 size <= SLUB_MAX_SIZE && !(flags & SLUB_DMA)) {
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700289 struct kmem_cache *s = kmalloc_slab(size);
Christoph Lameter81819f02007-05-06 14:49:36 -0700290
291 if (!s)
Christoph Lameter272c1d22007-06-08 13:46:49 -0700292 return ZERO_SIZE_PTR;
Christoph Lameter81819f02007-05-06 14:49:36 -0700293
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300294 ret = kmem_cache_alloc_node_notrace(s, flags, node);
295
Eduard - Gabriel Munteanuca2b84c2009-03-23 15:12:24 +0200296 trace_kmalloc_node(_THIS_IP_, ret,
297 size, s->size, flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +0300298
299 return ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -0700300 }
301 return __kmalloc_node(size, flags, node);
Christoph Lameter81819f02007-05-06 14:49:36 -0700302}
303#endif
304
Christoph Lameter81819f02007-05-06 14:49:36 -0700305#endif /* _LINUX_SLUB_DEF_H */