1 #ifndef _LINUX_SLUB_DEF_H
2 #define _LINUX_SLUB_DEF_H
5 * SLUB : A Slab allocator without object queues.
7 * (C) 2007 SGI, Christoph Lameter
9 #include <linux/types.h>
10 #include <linux/gfp.h>
11 #include <linux/workqueue.h>
12 #include <linux/kobject.h>
13 #include <trace/kmemtrace.h>
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 */
33 ORDER_FALLBACK, /* Number of times fallback was necessary */
36 struct kmem_cache_cpu {
37 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) */
42 #ifdef CONFIG_SLUB_STATS
43 unsigned stat[NR_SLUB_STAT_ITEMS];
47 struct kmem_cache_node {
48 spinlock_t list_lock; /* Protect partial list and nr_partial */
49 unsigned long nr_partial;
50 unsigned long min_partial;
51 struct list_head partial;
52 #ifdef CONFIG_SLUB_DEBUG
53 atomic_long_t nr_slabs;
54 atomic_long_t total_objects;
55 struct list_head full;
60 * Word size structure that can be atomically updated or read and that
61 * contains both the order and the number of objects that a slab of the
62 * given order would contain.
64 struct kmem_cache_order_objects {
69 * Slab cache management.
72 /* Used for retriving partial slabs etc */
74 int size; /* The size of an object including meta data */
75 int objsize; /* The size of an object without meta data */
76 int offset; /* Free pointer offset. */
77 struct kmem_cache_order_objects oo;
80 * Avoid an extra cache line for UP, SMP and for the node local to
83 struct kmem_cache_node local_node;
85 /* Allocation and freeing of slabs */
86 struct kmem_cache_order_objects max;
87 struct kmem_cache_order_objects min;
88 gfp_t allocflags; /* gfp flags to use on each alloc */
89 int refcount; /* Refcount for slab cache destroy */
91 int inuse; /* Offset to metadata */
92 int align; /* Alignment */
93 const char *name; /* Name (only for display!) */
94 struct list_head list; /* List of slab caches */
95 #ifdef CONFIG_SLUB_DEBUG
96 struct kobject kobj; /* For sysfs */
101 * Defragmentation by allocating from a remote node.
103 int remote_node_defrag_ratio;
104 struct kmem_cache_node *node[MAX_NUMNODES];
107 struct kmem_cache_cpu *cpu_slab[NR_CPUS];
109 struct kmem_cache_cpu cpu_slab;
116 #if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
117 #define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
119 #define KMALLOC_MIN_SIZE 8
122 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
125 * We keep the general caches in an array of slab caches that are used for
126 * 2^x bytes of allocations.
128 extern struct kmem_cache kmalloc_caches[PAGE_SHIFT + 1];
131 * Sorry that the following has to be that ugly but some versions of GCC
132 * have trouble with constant propagation and loops.
134 static __always_inline int kmalloc_index(size_t size)
139 if (size <= KMALLOC_MIN_SIZE)
140 return KMALLOC_SHIFT_LOW;
142 #if KMALLOC_MIN_SIZE <= 64
143 if (size > 64 && size <= 96)
145 if (size > 128 && size <= 192)
148 if (size <= 8) return 3;
149 if (size <= 16) return 4;
150 if (size <= 32) return 5;
151 if (size <= 64) return 6;
152 if (size <= 128) return 7;
153 if (size <= 256) return 8;
154 if (size <= 512) return 9;
155 if (size <= 1024) return 10;
156 if (size <= 2 * 1024) return 11;
157 if (size <= 4 * 1024) return 12;
159 * The following is only needed to support architectures with a larger page
162 if (size <= 8 * 1024) return 13;
163 if (size <= 16 * 1024) return 14;
164 if (size <= 32 * 1024) return 15;
165 if (size <= 64 * 1024) return 16;
166 if (size <= 128 * 1024) return 17;
167 if (size <= 256 * 1024) return 18;
168 if (size <= 512 * 1024) return 19;
169 if (size <= 1024 * 1024) return 20;
170 if (size <= 2 * 1024 * 1024) return 21;
174 * What we really wanted to do and cannot do because of compiler issues is:
176 * for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
177 * if (size <= (1 << i))
183 * Find the slab cache for a given combination of allocation flags and size.
185 * This ought to end up with a global pointer to the right cache
188 static __always_inline struct kmem_cache *kmalloc_slab(size_t size)
190 int index = kmalloc_index(size);
195 return &kmalloc_caches[index];
198 #ifdef CONFIG_ZONE_DMA
199 #define SLUB_DMA __GFP_DMA
201 /* Disable DMA functionality */
202 #define SLUB_DMA (__force gfp_t)0
205 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
206 void *__kmalloc(size_t size, gfp_t flags);
208 #ifdef CONFIG_KMEMTRACE
209 extern void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags);
211 static __always_inline void *
212 kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
214 return kmem_cache_alloc(s, gfpflags);
218 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
220 unsigned int order = get_order(size);
221 void *ret = (void *) __get_free_pages(flags | __GFP_COMP, order);
223 kmemtrace_mark_alloc(KMEMTRACE_TYPE_KMALLOC, _THIS_IP_, ret,
224 size, PAGE_SIZE << order, flags);
229 static __always_inline void *kmalloc(size_t size, gfp_t flags)
233 if (__builtin_constant_p(size)) {
234 if (size > PAGE_SIZE)
235 return kmalloc_large(size, flags);
237 if (!(flags & SLUB_DMA)) {
238 struct kmem_cache *s = kmalloc_slab(size);
241 return ZERO_SIZE_PTR;
243 ret = kmem_cache_alloc_notrace(s, flags);
245 kmemtrace_mark_alloc(KMEMTRACE_TYPE_KMALLOC,
247 size, s->size, flags);
252 return __kmalloc(size, flags);
256 void *__kmalloc_node(size_t size, gfp_t flags, int node);
257 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
259 #ifdef CONFIG_KMEMTRACE
260 extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
264 static __always_inline void *
265 kmem_cache_alloc_node_notrace(struct kmem_cache *s,
269 return kmem_cache_alloc_node(s, gfpflags, node);
273 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
277 if (__builtin_constant_p(size) &&
278 size <= PAGE_SIZE && !(flags & SLUB_DMA)) {
279 struct kmem_cache *s = kmalloc_slab(size);
282 return ZERO_SIZE_PTR;
284 ret = kmem_cache_alloc_node_notrace(s, flags, node);
286 kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_KMALLOC,
288 size, s->size, flags, node);
292 return __kmalloc_node(size, flags, node);
296 #endif /* _LINUX_SLUB_DEF_H */