[PATCH] slab: page mapping cleanup

Clean up slab allocator page mapping a bit.  The memory allocated for a
slab is physically contiguous so it is okay to assume struct pages are too
so kill the long-standing comment.  Furthermore, rename set_slab_attr to
slab_map_pages and add a comment explaining why its needed.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Pekka Enberg 2006-06-23 02:03:07 -07:00 committed by Linus Torvalds
parent f886ed443f
commit 4776874ff0

View File

@ -2499,23 +2499,28 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
slabp->inuse--;
}
static void set_slab_attr(struct kmem_cache *cachep, struct slab *slabp,
void *objp)
/*
* Map pages beginning at addr to the given cache and slab. This is required
* for the slab allocator to be able to lookup the cache and slab of a
* virtual address for kfree, ksize, kmem_ptr_validate, and slab debugging.
*/
static void slab_map_pages(struct kmem_cache *cache, struct slab *slab,
void *addr)
{
int i;
int nr_pages;
struct page *page;
/* Nasty!!!!!! I hope this is OK. */
page = virt_to_page(objp);
page = virt_to_page(addr);
i = 1;
nr_pages = 1;
if (likely(!PageCompound(page)))
i <<= cachep->gfporder;
nr_pages <<= cache->gfporder;
do {
page_set_cache(page, cachep);
page_set_slab(page, slabp);
page_set_cache(page, cache);
page_set_slab(page, slab);
page++;
} while (--i);
} while (--nr_pages);
}
/*
@ -2587,7 +2592,7 @@ static int cache_grow(struct kmem_cache *cachep, gfp_t flags, int nodeid)
goto opps1;
slabp->nodeid = nodeid;
set_slab_attr(cachep, slabp, objp);
slab_map_pages(cachep, slabp, objp);
cache_init_objs(cachep, slabp, ctor_flags);