Slab allocators: consolidate code for krealloc in mm/util.c

The size of a kmalloc object is readily available via ksize().  ksize is
provided by all allocators and thus we can implement krealloc in a generic
way.

Implement krealloc in mm/util.c and drop slab specific implementations of
krealloc.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Christoph Lameter 2007-07-17 04:03:21 -07:00 committed by Linus Torvalds
parent d45f39cb06
commit ef2ad80c7d
4 changed files with 34 additions and 116 deletions

View File

@ -3725,52 +3725,6 @@ void *__kmalloc(size_t size, gfp_t flags)
EXPORT_SYMBOL(__kmalloc);
#endif
/**
* krealloc - reallocate memory. The contents will remain unchanged.
* @p: object to reallocate memory for.
* @new_size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*
* The contents of the object pointed to are preserved up to the
* lesser of the new and old sizes. If @p is %NULL, krealloc()
* behaves exactly like kmalloc(). If @size is 0 and @p is not a
* %NULL pointer, the object pointed to is freed.
*/
void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
struct kmem_cache *cache, *new_cache;
void *ret;
if (unlikely(!p))
return kmalloc_track_caller(new_size, flags);
if (unlikely(!new_size)) {
kfree(p);
return NULL;
}
cache = virt_to_cache(p);
new_cache = __find_general_cachep(new_size, flags);
/*
* If new size fits in the current cache, bail out.
*/
if (likely(cache == new_cache))
return (void *)p;
/*
* We are on the slow-path here so do not use __cache_alloc
* because it bloats kernel text.
*/
ret = kmalloc_track_caller(new_size, flags);
if (ret) {
memcpy(ret, p, min(new_size, ksize(p)));
kfree(p);
}
return ret;
}
EXPORT_SYMBOL(krealloc);
/**
* kmem_cache_free - Deallocate an object
* @cachep: The cache the allocation was from.

View File

@ -446,39 +446,6 @@ void *__kmalloc_node(size_t size, gfp_t gfp, int node)
}
EXPORT_SYMBOL(__kmalloc_node);
/**
* krealloc - reallocate memory. The contents will remain unchanged.
*
* @p: object to reallocate memory for.
* @new_size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*
* The contents of the object pointed to are preserved up to the
* lesser of the new and old sizes. If @p is %NULL, krealloc()
* behaves exactly like kmalloc(). If @size is 0 and @p is not a
* %NULL pointer, the object pointed to is freed.
*/
void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
void *ret;
if (unlikely(!p))
return kmalloc_track_caller(new_size, flags);
if (unlikely(!new_size)) {
kfree(p);
return NULL;
}
ret = kmalloc_track_caller(new_size, flags);
if (ret) {
memcpy(ret, p, min(new_size, ksize(p)));
kfree(p);
}
return ret;
}
EXPORT_SYMBOL(krealloc);
void kfree(const void *block)
{
struct slob_page *sp;

View File

@ -2467,43 +2467,6 @@ int kmem_cache_shrink(struct kmem_cache *s)
}
EXPORT_SYMBOL(kmem_cache_shrink);
/**
* krealloc - reallocate memory. The contents will remain unchanged.
* @p: object to reallocate memory for.
* @new_size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*
* The contents of the object pointed to are preserved up to the
* lesser of the new and old sizes. If @p is %NULL, krealloc()
* behaves exactly like kmalloc(). If @size is 0 and @p is not a
* %NULL pointer, the object pointed to is freed.
*/
void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
void *ret;
size_t ks;
if (unlikely(!p || p == ZERO_SIZE_PTR))
return kmalloc(new_size, flags);
if (unlikely(!new_size)) {
kfree(p);
return ZERO_SIZE_PTR;
}
ks = ksize(p);
if (ks >= new_size)
return (void *)p;
ret = kmalloc(new_size, flags);
if (ret) {
memcpy(ret, p, min(new_size, ks));
kfree(p);
}
return ret;
}
EXPORT_SYMBOL(krealloc);
/********************************************************************
* Basic setup of slabs
*******************************************************************/

View File

@ -58,6 +58,40 @@ void *kmemdup(const void *src, size_t len, gfp_t gfp)
}
EXPORT_SYMBOL(kmemdup);
/**
* krealloc - reallocate memory. The contents will remain unchanged.
* @p: object to reallocate memory for.
* @new_size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*
* The contents of the object pointed to are preserved up to the
* lesser of the new and old sizes. If @p is %NULL, krealloc()
* behaves exactly like kmalloc(). If @size is 0 and @p is not a
* %NULL pointer, the object pointed to is freed.
*/
void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
void *ret;
size_t ks;
if (unlikely(!new_size)) {
kfree(p);
return NULL;
}
ks = ksize(p);
if (ks >= new_size)
return (void *)p;
ret = kmalloc_track_caller(new_size, flags);
if (ret) {
memcpy(ret, p, min(new_size, ks));
kfree(p);
}
return ret;
}
EXPORT_SYMBOL(krealloc);
/*
* strndup_user - duplicate an existing string from user space
*