linux-kernel - Re: [PATCH 00/16] slab: overload struct slab over struct page to reduce memory usage

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <20130904082505.GA16355@lge.com>
Date:	Wed, 4 Sep 2013 17:25:05 +0900
From:	Joonsoo Kim <iamjoonsoo.kim@....com>
To:	Wanpeng Li <liwanp@...ux.vnet.ibm.com>
Cc:	Christoph Lameter <cl@...ux.com>,
	Pekka Enberg <penberg@...nel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Rientjes <rientjes@...gle.com>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 00/16] slab: overload struct slab over struct page to
 reduce memory usage

On Wed, Sep 04, 2013 at 11:38:04AM +0800, Wanpeng Li wrote:
> Hi Joonsoo,
> On Fri, Aug 23, 2013 at 03:35:39PM +0900, Joonsoo Kim wrote:
> >On Thu, Aug 22, 2013 at 04:47:25PM +0000, Christoph Lameter wrote:
> >> On Thu, 22 Aug 2013, Joonsoo Kim wrote:
> >
> [...]
> >struct slab's free = END
> >kmem_bufctl_t array: ACTIVE ACTIVE ACTIVE ACTIVE ACTIVE
> ><we get object at index 0>
> >
> 
> Is there a real item for END in kmem_bufctl_t array as you mentioned above?
> I think the kmem_bufctl_t array doesn't include that and the last step is 
> not present. 

Yes, there is. BUFCTL_END is what I told for END. A slab is initialized in
cache_init_objs() and a last step in that function is to set last entry of
a free array of a slab to BUFCTL_END. This value remains in the whole life
cycle of a slab.

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