2 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
4 * (C) SGI 2006, Christoph Lameter <clameter@sgi.com>
5 * Cleaned up and restructured to ease the addition of alternative
6 * implementations of SLAB allocators.
14 #include <linux/gfp.h>
15 #include <linux/types.h>
18 * Flags to pass to kmem_cache_create().
19 * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set.
21 #define SLAB_DEBUG_FREE 0x00000100UL /* DEBUG: Perform (expensive) checks on free */
22 #define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */
23 #define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */
24 #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */
25 #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */
26 #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */
27 #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
28 #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
29 #define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
30 #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
31 #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */
34 * struct kmem_cache related prototypes
36 void __init kmem_cache_init(void);
37 int slab_is_available(void);
39 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
41 void (*)(void *, struct kmem_cache *, unsigned long),
42 void (*)(void *, struct kmem_cache *, unsigned long));
43 void kmem_cache_destroy(struct kmem_cache *);
44 int kmem_cache_shrink(struct kmem_cache *);
45 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
46 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
47 void kmem_cache_free(struct kmem_cache *, void *);
48 unsigned int kmem_cache_size(struct kmem_cache *);
49 const char *kmem_cache_name(struct kmem_cache *);
50 int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr);
53 * Please use this macro to create slab caches. Simply specify the
54 * name of the structure and maybe some flags that are listed above.
56 * The alignment of the struct determines object alignment. If you
57 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
58 * then the objects will be properly aligned in SMP configurations.
60 #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
61 sizeof(struct __struct), __alignof__(struct __struct),\
62 (__flags), NULL, NULL)
65 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
67 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
68 gfp_t flags, int node)
70 return kmem_cache_alloc(cachep, flags);
75 * The largest kmalloc size supported by the slab allocators is
76 * 32 megabyte (2^25) or the maximum allocatable page order if that is
79 * WARNING: Its not easy to increase this value since the allocators have
80 * to do various tricks to work around compiler limitations in order to
81 * ensure proper constant folding.
83 #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
84 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
86 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH)
87 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT)
90 * Common kmalloc functions provided by all allocators
92 void *__kmalloc(size_t, gfp_t);
93 void *__kzalloc(size_t, gfp_t);
94 void * __must_check krealloc(const void *, size_t, gfp_t);
95 void kfree(const void *);
96 size_t ksize(const void *);
99 * kcalloc - allocate memory for an array. The memory is set to zero.
100 * @n: number of elements.
101 * @size: element size.
102 * @flags: the type of memory to allocate.
104 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
106 if (n != 0 && size > ULONG_MAX / n)
108 return __kzalloc(n * size, flags);
112 * Allocator specific definitions. These are mainly used to establish optimized
113 * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by selecting
114 * the appropriate general cache at compile time.
117 #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB)
119 #include <linux/slub_def.h>
121 #include <linux/slab_def.h>
122 #endif /* !CONFIG_SLUB */
126 * Fallback definitions for an allocator not wanting to provide
127 * its own optimized kmalloc definitions (like SLOB).
131 * kmalloc - allocate memory
132 * @size: how many bytes of memory are required.
133 * @flags: the type of memory to allocate.
135 * kmalloc is the normal method of allocating memory
138 * The @flags argument may be one of:
140 * %GFP_USER - Allocate memory on behalf of user. May sleep.
142 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
144 * %GFP_ATOMIC - Allocation will not sleep.
145 * For example, use this inside interrupt handlers.
147 * %GFP_HIGHUSER - Allocate pages from high memory.
149 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
151 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
153 * Also it is possible to set different flags by OR'ing
154 * in one or more of the following additional @flags:
156 * %__GFP_COLD - Request cache-cold pages instead of
157 * trying to return cache-warm pages.
159 * %__GFP_DMA - Request memory from the DMA-capable zone.
161 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
163 * %__GFP_HIGHMEM - Allocated memory may be from highmem.
165 * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
166 * (think twice before using).
168 * %__GFP_NORETRY - If memory is not immediately available,
169 * then give up at once.
171 * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
173 * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
175 static inline void *kmalloc(size_t size, gfp_t flags)
177 return __kmalloc(size, flags);
181 * kzalloc - allocate memory. The memory is set to zero.
182 * @size: how many bytes of memory are required.
183 * @flags: the type of memory to allocate (see kmalloc).
185 static inline void *kzalloc(size_t size, gfp_t flags)
187 return __kzalloc(size, flags);
192 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
194 return kmalloc(size, flags);
197 static inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
199 return __kmalloc(size, flags);
201 #endif /* !CONFIG_NUMA */
204 * kmalloc_track_caller is a special version of kmalloc that records the
205 * calling function of the routine calling it for slab leak tracking instead
206 * of just the calling function (confusing, eh?).
207 * It's useful when the call to kmalloc comes from a widely-used standard
208 * allocator where we care about the real place the memory allocation
209 * request comes from.
211 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
212 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
213 #define kmalloc_track_caller(size, flags) \
214 __kmalloc_track_caller(size, flags, __builtin_return_address(0))
216 #define kmalloc_track_caller(size, flags) \
217 __kmalloc(size, flags)
218 #endif /* DEBUG_SLAB */
222 * kmalloc_node_track_caller is a special version of kmalloc_node that
223 * records the calling function of the routine calling it for slab leak
224 * tracking instead of just the calling function (confusing, eh?).
225 * It's useful when the call to kmalloc_node comes from a widely-used
226 * standard allocator where we care about the real place the memory
227 * allocation request comes from.
229 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
230 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
231 #define kmalloc_node_track_caller(size, flags, node) \
232 __kmalloc_node_track_caller(size, flags, node, \
233 __builtin_return_address(0))
235 #define kmalloc_node_track_caller(size, flags, node) \
236 __kmalloc_node(size, flags, node)
239 #else /* CONFIG_NUMA */
241 #define kmalloc_node_track_caller(size, flags, node) \
242 kmalloc_track_caller(size, flags)
244 #endif /* DEBUG_SLAB */
246 #endif /* __KERNEL__ */
247 #endif /* _LINUX_SLAB_H */