diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 231 |
1 files changed, 163 insertions, 68 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index 5d168d7e0a28..0c621752caa6 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -94,29 +94,6 @@ #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \ (unsigned long)ZERO_SIZE_PTR) -/* - * Common fields provided in kmem_cache by all slab allocators - * This struct is either used directly by the allocator (SLOB) - * or the allocator must include definitions for all fields - * provided in kmem_cache_common in their definition of kmem_cache. - * - * Once we can do anonymous structs (C11 standard) we could put a - * anonymous struct definition in these allocators so that the - * separate allocations in the kmem_cache structure of SLAB and - * SLUB is no longer needed. - */ -#ifdef CONFIG_SLOB -struct kmem_cache { - unsigned int object_size;/* The original size of the object */ - unsigned int size; /* The aligned/padded/added on size */ - unsigned int align; /* Alignment as calculated */ - unsigned long flags; /* Active flags on the slab */ - const char *name; /* Slab name for sysfs */ - int refcount; /* Use counter */ - void (*ctor)(void *); /* Called on object slot creation */ - struct list_head list; /* List of all slab caches on the system */ -}; -#endif struct mem_cgroup; /* @@ -148,7 +125,63 @@ void kmem_cache_free(struct kmem_cache *, void *); (__flags), NULL) /* - * The largest kmalloc size supported by the slab allocators is + * Common kmalloc functions provided by all allocators + */ +void * __must_check __krealloc(const void *, size_t, gfp_t); +void * __must_check krealloc(const void *, size_t, gfp_t); +void kfree(const void *); +void kzfree(const void *); +size_t ksize(const void *); + +/* + * Some archs want to perform DMA into kmalloc caches and need a guaranteed + * alignment larger than the alignment of a 64-bit integer. + * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that. + */ +#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8 +#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN +#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN +#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN) +#else +#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) +#endif + +#ifdef CONFIG_SLOB +/* + * Common fields provided in kmem_cache by all slab allocators + * This struct is either used directly by the allocator (SLOB) + * or the allocator must include definitions for all fields + * provided in kmem_cache_common in their definition of kmem_cache. + * + * Once we can do anonymous structs (C11 standard) we could put a + * anonymous struct definition in these allocators so that the + * separate allocations in the kmem_cache structure of SLAB and + * SLUB is no longer needed. + */ +struct kmem_cache { + unsigned int object_size;/* The original size of the object */ + unsigned int size; /* The aligned/padded/added on size */ + unsigned int align; /* Alignment as calculated */ + unsigned long flags; /* Active flags on the slab */ + const char *name; /* Slab name for sysfs */ + int refcount; /* Use counter */ + void (*ctor)(void *); /* Called on object slot creation */ + struct list_head list; /* List of all slab caches on the system */ +}; + +#define KMALLOC_MAX_SIZE (1UL << 30) + +#include <linux/slob_def.h> + +#else /* CONFIG_SLOB */ + +/* + * Kmalloc array related definitions + */ + +#ifdef CONFIG_SLAB +/* + * The largest kmalloc size supported by the SLAB allocators is * 32 megabyte (2^25) or the maximum allocatable page order if that is * less than 32 MB. * @@ -158,22 +191,120 @@ void kmem_cache_free(struct kmem_cache *, void *); */ #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ (MAX_ORDER + PAGE_SHIFT - 1) : 25) +#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH +#ifndef KMALLOC_SHIFT_LOW +#define KMALLOC_SHIFT_LOW 5 +#endif +#else +/* + * SLUB allocates up to order 2 pages directly and otherwise + * passes the request to the page allocator. + */ +#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) +#ifndef KMALLOC_SHIFT_LOW +#define KMALLOC_SHIFT_LOW 3 +#endif +#endif -#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH) -#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT) +/* Maximum allocatable size */ +#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) +/* Maximum size for which we actually use a slab cache */ +#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH) +/* Maximum order allocatable via the slab allocagtor */ +#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT) /* - * Some archs want to perform DMA into kmalloc caches and need a guaranteed - * alignment larger than the alignment of a 64-bit integer. - * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that. + * Kmalloc subsystem. */ -#ifdef ARCH_DMA_MINALIGN -#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN +#ifndef KMALLOC_MIN_SIZE +#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) +#endif + +extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1]; +#ifdef CONFIG_ZONE_DMA +extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1]; +#endif + +/* + * Figure out which kmalloc slab an allocation of a certain size + * belongs to. + * 0 = zero alloc + * 1 = 65 .. 96 bytes + * 2 = 120 .. 192 bytes + * n = 2^(n-1) .. 2^n -1 + */ +static __always_inline int kmalloc_index(size_t size) +{ + if (!size) + return 0; + + if (size <= KMALLOC_MIN_SIZE) + return KMALLOC_SHIFT_LOW; + + if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) + return 1; + if (KMALLOC_MIN_SIZE <= 64 && 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 (size <= 512 * 1024) return 19; + if (size <= 1024 * 1024) return 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; + if (size <= 64 * 1024 * 1024) return 26; + BUG(); + + /* Will never be reached. Needed because the compiler may complain */ + return -1; +} + +#ifdef CONFIG_SLAB +#include <linux/slab_def.h> +#elif defined(CONFIG_SLUB) +#include <linux/slub_def.h> #else -#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) +#error "Unknown slab allocator" #endif /* + * Determine size used for the nth kmalloc cache. + * return size or 0 if a kmalloc cache for that + * size does not exist + */ +static __always_inline int kmalloc_size(int n) +{ + if (n > 2) + return 1 << n; + + if (n == 1 && KMALLOC_MIN_SIZE <= 32) + return 96; + + if (n == 2 && KMALLOC_MIN_SIZE <= 64) + return 192; + + return 0; +} +#endif /* !CONFIG_SLOB */ + +/* * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment. * Intended for arches that get misalignment faults even for 64 bit integer * aligned buffers. @@ -224,42 +355,6 @@ struct seq_file; int cache_show(struct kmem_cache *s, struct seq_file *m); void print_slabinfo_header(struct seq_file *m); -/* - * Common kmalloc functions provided by all allocators - */ -void * __must_check __krealloc(const void *, size_t, gfp_t); -void * __must_check krealloc(const void *, size_t, gfp_t); -void kfree(const void *); -void kzfree(const void *); -size_t ksize(const void *); - -/* - * Allocator specific definitions. These are mainly used to establish optimized - * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by - * selecting the appropriate general cache at compile time. - * - * Allocators must define at least: - * - * kmem_cache_alloc() - * __kmalloc() - * kmalloc() - * - * Those wishing to support NUMA must also define: - * - * kmem_cache_alloc_node() - * kmalloc_node() - * - * See each allocator definition file for additional comments and - * implementation notes. - */ -#ifdef CONFIG_SLUB -#include <linux/slub_def.h> -#elif defined(CONFIG_SLOB) -#include <linux/slob_def.h> -#else -#include <linux/slab_def.h> -#endif - /** * kmalloc_array - allocate memory for an array. * @n: number of elements. |