kernel-ark/include/linux/slab.h
Christoph Lameter debee0768e slab allocators: MAX_ORDER one off fix
MAX_ORDER is the first order that is not possible.

Use MAX_ORDER - 1 to calculate the larges possible object size in slab.h

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:12 -07:00

251 lines
8.0 KiB
C

/*
* Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
*
* (C) SGI 2006, Christoph Lameter <clameter@sgi.com>
* Cleaned up and restructured to ease the addition of alternative
* implementations of SLAB allocators.
*/
#ifndef _LINUX_SLAB_H
#define _LINUX_SLAB_H
#ifdef __KERNEL__
#include <linux/gfp.h>
#include <linux/types.h>
typedef struct kmem_cache kmem_cache_t __deprecated;
/*
* 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_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
#define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
#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 */
/*
* 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 *, struct kmem_cache *, unsigned long),
void (*)(void *, struct kmem_cache *, unsigned long));
void kmem_cache_destroy(struct kmem_cache *);
int kmem_cache_shrink(struct kmem_cache *);
void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
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);
/*
* 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, NULL)
#ifdef CONFIG_NUMA
extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
#else
static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
gfp_t flags, int node)
{
return kmem_cache_alloc(cachep, flags);
}
#endif
/*
* 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)
/*
* Common kmalloc functions provided by all allocators
*/
void *__kmalloc(size_t, gfp_t);
void *__kzalloc(size_t, gfp_t);
void * __must_check krealloc(const void *, size_t, gfp_t);
void kfree(const void *);
size_t ksize(const void *);
/**
* 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)
{
if (n != 0 && size > ULONG_MAX / n)
return NULL;
return __kzalloc(n * 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.
*/
#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB)
#ifdef CONFIG_SLUB
#include <linux/slub_def.h>
#else
#include <linux/slab_def.h>
#endif /* !CONFIG_SLUB */
#else
/*
* Fallback definitions for an allocator not wanting to provide
* its own optimized kmalloc definitions (like SLOB).
*/
/**
* kmalloc - allocate memory
* @size: how many bytes of memory are required.
* @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.
* For example, use this inside interrupt handlers.
*
* %GFP_HIGHUSER - Allocate pages from high memory.
*
* %GFP_NOIO - Do not do any I/O at all while trying to get memory.
*
* %GFP_NOFS - Do not make any fs calls while trying to get memory.
*
* 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).
*
* %__GFP_NORETRY - If memory is not immediately available,
* then give up at once.
*
* %__GFP_NOWARN - If allocation fails, don't issue any warnings.
*
* %__GFP_REPEAT - If allocation fails initially, try once more before failing.
*/
static inline void *kmalloc(size_t size, gfp_t flags)
{
return __kmalloc(size, flags);
}
/**
* 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 __kzalloc(size, flags);
}
#endif
#ifndef CONFIG_NUMA
static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
return kmalloc(size, flags);
}
static inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
{
return __kmalloc(size, flags);
}
#endif /* !CONFIG_NUMA */
/*
* 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, void*);
#define kmalloc_track_caller(size, flags) \
__kmalloc_track_caller(size, flags, __builtin_return_address(0))
#else
#define kmalloc_track_caller(size, flags) \
__kmalloc(size, flags)
#endif /* DEBUG_SLAB */
#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, void *);
#define kmalloc_node_track_caller(size, flags, node) \
__kmalloc_node_track_caller(size, flags, node, \
__builtin_return_address(0))
#else
#define kmalloc_node_track_caller(size, flags, node) \
__kmalloc_node(size, flags, node)
#endif
#else /* CONFIG_NUMA */
#define kmalloc_node_track_caller(size, flags, node) \
kmalloc_track_caller(size, flags)
#endif /* DEBUG_SLAB */
#endif /* __KERNEL__ */
#endif /* _LINUX_SLAB_H */