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Diffstat (limited to 'include/linux/slub_def.h')
| -rw-r--r-- | include/linux/slub_def.h | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h new file mode 100644 index 000000000000..ea27065e80e6 --- /dev/null +++ b/include/linux/slub_def.h @@ -0,0 +1,206 @@ +#ifndef _LINUX_SLUB_DEF_H +#define _LINUX_SLUB_DEF_H + +/* + * SLUB : A Slab allocator without object queues. + * + * (C) 2007 SGI, Christoph Lameter <clameter@sgi.com> + */ +#include <linux/types.h> +#include <linux/gfp.h> +#include <linux/workqueue.h> +#include <linux/kobject.h> + +struct kmem_cache_node { + spinlock_t list_lock; /* Protect partial list and nr_partial */ + unsigned long nr_partial; + atomic_long_t nr_slabs; + struct list_head partial; + struct list_head full; +}; + +/* + * Slab cache management. + */ +struct kmem_cache { + /* Used for retriving partial slabs etc */ + unsigned long flags; + int size; /* The size of an object including meta data */ + int objsize; /* The size of an object without meta data */ + int offset; /* Free pointer offset. */ + unsigned int order; + + /* + * Avoid an extra cache line for UP, SMP and for the node local to + * struct kmem_cache. + */ + struct kmem_cache_node local_node; + + /* Allocation and freeing of slabs */ + int objects; /* Number of objects in slab */ + int refcount; /* Refcount for slab cache destroy */ + void (*ctor)(void *, struct kmem_cache *, unsigned long); + void (*dtor)(void *, struct kmem_cache *, unsigned long); + int inuse; /* Offset to metadata */ + int align; /* Alignment */ + const char *name; /* Name (only for display!) */ + struct list_head list; /* List of slab caches */ + struct kobject kobj; /* For sysfs */ + +#ifdef CONFIG_NUMA + int defrag_ratio; + struct kmem_cache_node *node[MAX_NUMNODES]; +#endif + struct page *cpu_slab[NR_CPUS]; +}; + +/* + * Kmalloc subsystem. + */ +#define KMALLOC_SHIFT_LOW 3 + +#ifdef CONFIG_LARGE_ALLOCS +#define KMALLOC_SHIFT_HIGH 25 +#else +#if !defined(CONFIG_MMU) || NR_CPUS > 512 || MAX_NUMNODES > 256 +#define KMALLOC_SHIFT_HIGH 20 +#else +#define KMALLOC_SHIFT_HIGH 18 +#endif +#endif + +/* + * We keep the general caches in an array of slab caches that are used for + * 2^x bytes of allocations. + */ +extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1]; + +/* + * Sorry that the following has to be that ugly but some versions of GCC + * have trouble with constant propagation and loops. + */ +static inline int kmalloc_index(int size) +{ + /* + * We should return 0 if size == 0 but we use the smallest object + * here for SLAB legacy reasons. + */ + WARN_ON_ONCE(size == 0); + + if (size > 64 && size <= 96) + return 1; + if (size > 128 && size <= 192) + return 2; + if (size <= 8) return 3; + if (size <= 16) return 4; + if (size <= 32) return 5; + if (size <= 64) return 6; + if (size <= 128) return 7; + if (size <= 256) return 8; + if (size <= 512) return 9; + if (size <= 1024) return 10; + if (size <= 2 * 1024) return 11; + if (size <= 4 * 1024) return 12; + if (size <= 8 * 1024) return 13; + if (size <= 16 * 1024) return 14; + if (size <= 32 * 1024) return 15; + if (size <= 64 * 1024) return 16; + if (size <= 128 * 1024) return 17; + if (size <= 256 * 1024) return 18; +#if KMALLOC_SHIFT_HIGH > 18 + if (size <= 512 * 1024) return 19; + if (size <= 1024 * 1024) return 20; +#endif +#if KMALLOC_SHIFT_HIGH > 20 + if (size <= 2 * 1024 * 1024) return 21; + if (size <= 4 * 1024 * 1024) return 22; + if (size <= 8 * 1024 * 1024) return 23; + if (size <= 16 * 1024 * 1024) return 24; + if (size <= 32 * 1024 * 1024) return 25; +#endif + return -1; + +/* + * What we really wanted to do and cannot do because of compiler issues is: + * int i; + * for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) + * if (size <= (1 << i)) + * return i; + */ +} + +/* + * Find the slab cache for a given combination of allocation flags and size. + * + * This ought to end up with a global pointer to the right cache + * in kmalloc_caches. + */ +static inline struct kmem_cache *kmalloc_slab(size_t size) +{ + int index = kmalloc_index(size); + + if (index == 0) + return NULL; + + if (index < 0) { + /* + * Generate a link failure. Would be great if we could + * do something to stop the compile here. + */ + extern void __kmalloc_size_too_large(void); + __kmalloc_size_too_large(); + } + return &kmalloc_caches[index]; +} + +#ifdef CONFIG_ZONE_DMA +#define SLUB_DMA __GFP_DMA +#else +/* Disable DMA functionality */ +#define SLUB_DMA 0 +#endif + +static inline void *kmalloc(size_t size, gfp_t flags) +{ + if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) { + struct kmem_cache *s = kmalloc_slab(size); + + if (!s) + return NULL; + + return kmem_cache_alloc(s, flags); + } else + return __kmalloc(size, flags); +} + +static inline void *kzalloc(size_t size, gfp_t flags) +{ + if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) { + struct kmem_cache *s = kmalloc_slab(size); + + if (!s) + return NULL; + + return kmem_cache_zalloc(s, flags); + } else + return __kzalloc(size, flags); +} + +#ifdef CONFIG_NUMA +extern void *__kmalloc_node(size_t size, gfp_t flags, int node); + +static inline void *kmalloc_node(size_t size, gfp_t flags, int node) +{ + if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) { + struct kmem_cache *s = kmalloc_slab(size); + + if (!s) + return NULL; + + return kmem_cache_alloc_node(s, flags, node); + } else + return __kmalloc_node(size, flags, node); +} +#endif + +#endif /* _LINUX_SLUB_DEF_H */ |