X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=include%2Flinux%2Fslab.h;h=2da8372519f5e96a32027a9be8b0efc66f35b907;hb=9a1607071c293e48b08bd703733480b1d55c7b93;hp=2f6bef6a98c9e01b03896d9326a9828b5dbd5fcb;hpb=dbe5e69d2d6e591996ea2b817b887d03b60bb143;p=safe%2Fjmp%2Flinux-2.6 diff --git a/include/linux/slab.h b/include/linux/slab.h index 2f6bef6..2da8372 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -1,105 +1,184 @@ /* - * linux/mm/slab.h - * Written by Mark Hemment, 1996. - * (markhe@nextd.demon.co.uk) + * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk). + * + * (C) SGI 2006, Christoph Lameter + * Cleaned up and restructured to ease the addition of alternative + * implementations of SLAB allocators. */ #ifndef _LINUX_SLAB_H #define _LINUX_SLAB_H -#if defined(__KERNEL__) - -typedef struct kmem_cache kmem_cache_t; +#include +#include -#include -#include -#include -#include /* kmalloc_sizes.h needs PAGE_SIZE */ -#include /* kmalloc_sizes.h needs L1_CACHE_BYTES */ +/* + * Flags to pass to kmem_cache_create(). + * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set. + */ +#define SLAB_DEBUG_FREE 0x00000100UL /* DEBUG: Perform (expensive) checks on free */ +#define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */ +#define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */ +#define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */ +#define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */ +#define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */ +#define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */ +/* + * SLAB_DESTROY_BY_RCU - **WARNING** READ THIS! + * + * This delays freeing the SLAB page by a grace period, it does _NOT_ + * delay object freeing. This means that if you do kmem_cache_free() + * that memory location is free to be reused at any time. Thus it may + * be possible to see another object there in the same RCU grace period. + * + * This feature only ensures the memory location backing the object + * stays valid, the trick to using this is relying on an independent + * object validation pass. Something like: + * + * rcu_read_lock() + * again: + * obj = lockless_lookup(key); + * if (obj) { + * if (!try_get_ref(obj)) // might fail for free objects + * goto again; + * + * if (obj->key != key) { // not the object we expected + * put_ref(obj); + * goto again; + * } + * } + * rcu_read_unlock(); + * + * See also the comment on struct slab_rcu in mm/slab.c. + */ +#define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */ +#define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */ +#define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */ -/* flags for kmem_cache_alloc() */ -#define SLAB_NOFS GFP_NOFS -#define SLAB_NOIO GFP_NOIO -#define SLAB_ATOMIC GFP_ATOMIC -#define SLAB_USER GFP_USER -#define SLAB_KERNEL GFP_KERNEL -#define SLAB_DMA GFP_DMA +/* Flag to prevent checks on free */ +#ifdef CONFIG_DEBUG_OBJECTS +# define SLAB_DEBUG_OBJECTS 0x00400000UL +#else +# define SLAB_DEBUG_OBJECTS 0x00000000UL +#endif -#define SLAB_LEVEL_MASK GFP_LEVEL_MASK +#define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */ -#define SLAB_NO_GROW __GFP_NO_GROW /* don't grow a cache */ +/* Don't track use of uninitialized memory */ +#ifdef CONFIG_KMEMCHECK +# define SLAB_NOTRACK 0x01000000UL +#else +# define SLAB_NOTRACK 0x00000000UL +#endif -/* flags to pass to kmem_cache_create(). - * The first 3 are only valid when the allocator as been build - * SLAB_DEBUG_SUPPORT. +/* The following flags affect the page allocator grouping pages by mobility */ +#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ +#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ +/* + * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. + * + * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault. + * + * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can. + * Both make kfree a no-op. */ -#define SLAB_DEBUG_FREE 0x00000100UL /* Peform (expensive) checks on free */ -#define SLAB_DEBUG_INITIAL 0x00000200UL /* Call constructor (as verifier) */ -#define SLAB_RED_ZONE 0x00000400UL /* Red zone objs in a cache */ -#define SLAB_POISON 0x00000800UL /* Poison objects */ -#define SLAB_HWCACHE_ALIGN 0x00002000UL /* align objs on a h/w cache lines */ -#define SLAB_CACHE_DMA 0x00004000UL /* use GFP_DMA memory */ -#define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL /* force alignment */ -#define SLAB_STORE_USER 0x00010000UL /* store the last owner for bug hunting */ -#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* track pages allocated to indicate - what is reclaimable later*/ -#define SLAB_PANIC 0x00040000UL /* panic if kmem_cache_create() fails */ -#define SLAB_DESTROY_BY_RCU 0x00080000UL /* defer freeing pages to RCU */ -#define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */ +#define ZERO_SIZE_PTR ((void *)16) -/* flags passed to a constructor func */ -#define SLAB_CTOR_CONSTRUCTOR 0x001UL /* if not set, then deconstructor */ -#define SLAB_CTOR_ATOMIC 0x002UL /* tell constructor it can't sleep */ -#define SLAB_CTOR_VERIFY 0x004UL /* tell constructor it's a verify call */ +#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \ + (unsigned long)ZERO_SIZE_PTR) -#ifndef CONFIG_SLOB +/* + * struct kmem_cache related prototypes + */ +void __init kmem_cache_init(void); +int slab_is_available(void); + +struct kmem_cache *kmem_cache_create(const char *, size_t, size_t, + unsigned long, + void (*)(void *)); +void kmem_cache_destroy(struct kmem_cache *); +int kmem_cache_shrink(struct kmem_cache *); +void kmem_cache_free(struct kmem_cache *, void *); +unsigned int kmem_cache_size(struct kmem_cache *); +const char *kmem_cache_name(struct kmem_cache *); +int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr); -/* prototypes */ -extern void __init kmem_cache_init(void); +/* + * Please use this macro to create slab caches. Simply specify the + * name of the structure and maybe some flags that are listed above. + * + * The alignment of the struct determines object alignment. If you + * f.e. add ____cacheline_aligned_in_smp to the struct declaration + * then the objects will be properly aligned in SMP configurations. + */ +#define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\ + sizeof(struct __struct), __alignof__(struct __struct),\ + (__flags), NULL) -extern kmem_cache_t *kmem_cache_create(const char *, size_t, size_t, unsigned long, - void (*)(void *, kmem_cache_t *, unsigned long), - void (*)(void *, kmem_cache_t *, unsigned long)); -extern int kmem_cache_destroy(kmem_cache_t *); -extern int kmem_cache_shrink(kmem_cache_t *); -extern void *kmem_cache_alloc(kmem_cache_t *, gfp_t); -extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t); -extern void kmem_cache_free(kmem_cache_t *, void *); -extern unsigned int kmem_cache_size(kmem_cache_t *); -extern const char *kmem_cache_name(kmem_cache_t *); +/* + * 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. + * + * WARNING: Its not easy to increase this value since the allocators have + * to do various tricks to work around compiler limitations in order to + * ensure proper constant folding. + */ +#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ + (MAX_ORDER + PAGE_SHIFT - 1) : 25) + +#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH) +#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT) -/* Size description struct for general caches. */ -struct cache_sizes { - size_t cs_size; - kmem_cache_t *cs_cachep; - kmem_cache_t *cs_dmacachep; -}; -extern struct cache_sizes malloc_sizes[]; +/* + * 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 *); -extern void *__kmalloc(size_t, gfp_t); -#ifndef CONFIG_DEBUG_SLAB -#define ____kmalloc(size, flags) __kmalloc(size, flags) +/* + * 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 +#elif defined(CONFIG_SLOB) +#include #else -extern void *__kmalloc_track_caller(size_t, gfp_t, void*); -#define ____kmalloc(size, flags) \ - __kmalloc_track_caller(size, flags, __builtin_return_address(0)) +#include #endif /** - * kmalloc - allocate memory - * @size: how many bytes of memory are required. + * kcalloc - allocate memory for an array. The memory is set to zero. + * @n: number of elements. + * @size: element size. * @flags: the type of memory to allocate. * - * kmalloc is the normal method of allocating memory - * in the kernel. - * * The @flags argument may be one of: * * %GFP_USER - Allocate memory on behalf of user. May sleep. * * %GFP_KERNEL - Allocate normal kernel ram. May sleep. * - * %GFP_ATOMIC - Allocation will not sleep. + * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools. * For example, use this inside interrupt handlers. * * %GFP_HIGHUSER - Allocate pages from high memory. @@ -108,18 +187,22 @@ extern void *__kmalloc_track_caller(size_t, gfp_t, void*); * * %GFP_NOFS - Do not make any fs calls while trying to get memory. * + * %GFP_NOWAIT - Allocation will not sleep. + * + * %GFP_THISNODE - Allocate node-local memory only. + * + * %GFP_DMA - Allocation suitable for DMA. + * Should only be used for kmalloc() caches. Otherwise, use a + * slab created with SLAB_DMA. + * * Also it is possible to set different flags by OR'ing * in one or more of the following additional @flags: * * %__GFP_COLD - Request cache-cold pages instead of * trying to return cache-warm pages. * - * %__GFP_DMA - Request memory from the DMA-capable zone. - * * %__GFP_HIGH - This allocation has high priority and may use emergency pools. * - * %__GFP_HIGHMEM - Allocated memory may be from highmem. - * * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail * (think twice before using). * @@ -129,163 +212,120 @@ extern void *__kmalloc_track_caller(size_t, gfp_t, void*); * %__GFP_NOWARN - If allocation fails, don't issue any warnings. * * %__GFP_REPEAT - If allocation fails initially, try once more before failing. + * + * There are other flags available as well, but these are not intended + * for general use, and so are not documented here. For a full list of + * potential flags, always refer to linux/gfp.h. */ -static inline void *kmalloc(size_t size, gfp_t flags) +static inline void *kcalloc(size_t n, size_t size, gfp_t flags) { - if (__builtin_constant_p(size)) { - int i = 0; -#define CACHE(x) \ - if (size <= x) \ - goto found; \ - else \ - i++; -#include "kmalloc_sizes.h" -#undef CACHE - { - extern void __you_cannot_kmalloc_that_much(void); - __you_cannot_kmalloc_that_much(); - } -found: - return kmem_cache_alloc((flags & GFP_DMA) ? - malloc_sizes[i].cs_dmacachep : - malloc_sizes[i].cs_cachep, flags); - } - return __kmalloc(size, flags); + if (size != 0 && n > ULONG_MAX / size) + return NULL; + return __kmalloc(n * size, flags | __GFP_ZERO); } -extern void *__kzalloc(size_t, gfp_t); - +#if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB) /** - * kzalloc - allocate memory. The memory is set to zero. + * kmalloc_node - allocate memory from a specific node * @size: how many bytes of memory are required. - * @flags: the type of memory to allocate (see kmalloc). + * @flags: the type of memory to allocate (see kcalloc). + * @node: node to allocate from. + * + * kmalloc() for non-local nodes, used to allocate from a specific node + * if available. Equivalent to kmalloc() in the non-NUMA single-node + * case. */ -static inline void *kzalloc(size_t size, gfp_t flags) +static inline void *kmalloc_node(size_t size, gfp_t flags, int node) { - if (__builtin_constant_p(size)) { - int i = 0; -#define CACHE(x) \ - if (size <= x) \ - goto found; \ - else \ - i++; -#include "kmalloc_sizes.h" -#undef CACHE - { - extern void __you_cannot_kzalloc_that_much(void); - __you_cannot_kzalloc_that_much(); - } -found: - return kmem_cache_zalloc((flags & GFP_DMA) ? - malloc_sizes[i].cs_dmacachep : - malloc_sizes[i].cs_cachep, flags); - } - return __kzalloc(size, flags); + return kmalloc(size, flags); } -/** - * kcalloc - allocate memory for an array. The memory is set to zero. - * @n: number of elements. - * @size: element size. - * @flags: the type of memory to allocate. - */ -static inline void *kcalloc(size_t n, size_t size, gfp_t flags) +static inline void *__kmalloc_node(size_t size, gfp_t flags, int node) { - if (n != 0 && size > ULONG_MAX / n) - return NULL; - return kzalloc(n * size, flags); + return __kmalloc(size, flags); } -extern void kfree(const void *); -extern unsigned int ksize(const void *); -extern int slab_is_available(void); +void *kmem_cache_alloc(struct kmem_cache *, gfp_t); -#ifdef CONFIG_NUMA -extern void *kmem_cache_alloc_node(kmem_cache_t *, gfp_t flags, int node); -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)) { - int i = 0; -#define CACHE(x) \ - if (size <= x) \ - goto found; \ - else \ - i++; -#include "kmalloc_sizes.h" -#undef CACHE - { - extern void __you_cannot_kmalloc_that_much(void); - __you_cannot_kmalloc_that_much(); - } -found: - return kmem_cache_alloc_node((flags & GFP_DMA) ? - malloc_sizes[i].cs_dmacachep : - malloc_sizes[i].cs_cachep, flags, node); - } - return __kmalloc_node(size, flags, node); -} -#else -static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int node) +static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep, + gfp_t flags, int node) { return kmem_cache_alloc(cachep, flags); } -static inline void *kmalloc_node(size_t size, gfp_t flags, int node) -{ - return kmalloc(size, flags); -} -#endif +#endif /* !CONFIG_NUMA && !CONFIG_SLOB */ + +/* + * kmalloc_track_caller is a special version of kmalloc that records the + * calling function of the routine calling it for slab leak tracking instead + * of just the calling function (confusing, eh?). + * It's useful when the call to kmalloc comes from a widely-used standard + * allocator where we care about the real place the memory allocation + * request comes from. + */ +#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) +extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long); +#define kmalloc_track_caller(size, flags) \ + __kmalloc_track_caller(size, flags, _RET_IP_) +#else +#define kmalloc_track_caller(size, flags) \ + __kmalloc(size, flags) +#endif /* DEBUG_SLAB */ -extern int FASTCALL(kmem_cache_reap(int)); -extern int FASTCALL(kmem_ptr_validate(kmem_cache_t *cachep, void *ptr)); +#ifdef CONFIG_NUMA +/* + * kmalloc_node_track_caller is a special version of kmalloc_node that + * records the calling function of the routine calling it for slab leak + * tracking instead of just the calling function (confusing, eh?). + * It's useful when the call to kmalloc_node comes from a widely-used + * standard allocator where we care about the real place the memory + * allocation request comes from. + */ +#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) +extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long); +#define kmalloc_node_track_caller(size, flags, node) \ + __kmalloc_node_track_caller(size, flags, node, \ + _RET_IP_) +#else +#define kmalloc_node_track_caller(size, flags, node) \ + __kmalloc_node(size, flags, node) +#endif -#else /* CONFIG_SLOB */ +#else /* CONFIG_NUMA */ -/* SLOB allocator routines */ +#define kmalloc_node_track_caller(size, flags, node) \ + kmalloc_track_caller(size, flags) -void kmem_cache_init(void); -struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t, - unsigned long, - void (*)(void *, struct kmem_cache *, unsigned long), - void (*)(void *, struct kmem_cache *, unsigned long)); -int kmem_cache_destroy(struct kmem_cache *c); -void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags); -void *kmem_cache_zalloc(struct kmem_cache *, gfp_t); -void kmem_cache_free(struct kmem_cache *c, void *b); -const char *kmem_cache_name(struct kmem_cache *); -void *kmalloc(size_t size, gfp_t flags); -void *__kzalloc(size_t size, gfp_t flags); -void kfree(const void *m); -unsigned int ksize(const void *m); -unsigned int kmem_cache_size(struct kmem_cache *c); +#endif /* CONFIG_NUMA */ -static inline void *kcalloc(size_t n, size_t size, gfp_t flags) +/* + * Shortcuts + */ +static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags) { - return __kzalloc(n * size, flags); + return kmem_cache_alloc(k, flags | __GFP_ZERO); } -#define kmem_cache_shrink(d) (0) -#define kmem_cache_reap(a) -#define kmem_ptr_validate(a, b) (0) -#define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f) -#define kmalloc_node(s, f, n) kmalloc(s, f) -#define kzalloc(s, f) __kzalloc(s, f) -#define ____kmalloc kmalloc - -#endif /* CONFIG_SLOB */ - -/* System wide caches */ -extern kmem_cache_t *vm_area_cachep; -extern kmem_cache_t *names_cachep; -extern kmem_cache_t *files_cachep; -extern kmem_cache_t *filp_cachep; -extern kmem_cache_t *fs_cachep; -extern kmem_cache_t *sighand_cachep; -extern kmem_cache_t *bio_cachep; +/** + * kzalloc - allocate memory. The memory is set to zero. + * @size: how many bytes of memory are required. + * @flags: the type of memory to allocate (see kmalloc). + */ +static inline void *kzalloc(size_t size, gfp_t flags) +{ + return kmalloc(size, flags | __GFP_ZERO); +} -extern atomic_t slab_reclaim_pages; +/** + * kzalloc_node - allocate zeroed memory from a particular memory node. + * @size: how many bytes of memory are required. + * @flags: the type of memory to allocate (see kmalloc). + * @node: memory node from which to allocate + */ +static inline void *kzalloc_node(size_t size, gfp_t flags, int node) +{ + return kmalloc_node(size, flags | __GFP_ZERO, node); +} -#endif /* __KERNEL__ */ +void __init kmem_cache_init_late(void); #endif /* _LINUX_SLAB_H */