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 */