Re: [PATCH v3 03/16] slab: Ignore the cflgs bit in cache creation

From: Tejun Heo
Date: Fri Sep 21 2012 - 13:33:51 EST


On Tue, Sep 18, 2012 at 06:11:57PM +0400, Glauber Costa wrote:
> No cache should ever pass that as a creation flag, since this bit is
> used to mark an internal decision of the slab about object placement. We
> can just ignore this bit if it happens to be passed (such as when
> duplicating a cache in the kmem memcg patches)
>
> Signed-off-by: Glauber Costa <glommer@xxxxxxxxxxxxx>
> CC: Christoph Lameter <cl@xxxxxxxxx>
> CC: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
> CC: David Rientjes <rientjes@xxxxxxxxxx>
> ---
> mm/slab.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/mm/slab.c b/mm/slab.c
> index a7ed60f..ccf496c 100644
> --- a/mm/slab.c
> +++ b/mm/slab.c
> @@ -2373,6 +2373,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
> int err;
> size_t size = cachep->size;
>
> + flags &= ~CFLGS_OFF_SLAB;

A comment explaining why this is necessary wouldn't hurt.

Thanks.

--
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/