linux-kernel - Re: [PATCH 08/40] mm: kmem_cache

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

Message-ID: <Pine.LNX.4.64.0705040919560.21436@schroedinger.engr.sgi.com>
Date:	Fri, 4 May 2007 09:23:04 -0700 (PDT)
From:	Christoph Lameter <clameter@....com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
cc:	Pekka Enberg <penberg@...helsinki.fi>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	netdev@...r.kernel.org,
	Trond Myklebust <trond.myklebust@....uio.no>,
	Thomas Graf <tgraf@...g.ch>,
	David Miller <davem@...emloft.net>,
	James Bottomley <James.Bottomley@...eleye.com>,
	Mike Christie <michaelc@...wisc.edu>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Daniel Phillips <phillips@...gle.com>
Subject: Re: [PATCH 08/40] mm: kmem_cache_objsize

On Fri, 4 May 2007, Peter Zijlstra wrote:

> On Fri, 2007-05-04 at 09:09 -0700, Christoph Lameter wrote:
> > On Fri, 4 May 2007, Pekka Enberg wrote:
> > 
> > > On 5/4/07, Peter Zijlstra <a.p.zijlstra@...llo.nl> wrote:
> > > > Expost buffer_size in order to allow fair estimates on the actual space
> > > > used/needed.
> > 
> > We already have ksize?
> 
> ksize gives the internal size, whereas these give the external size.
> 
> I need to know how much space I need to reserve, hence I need the
> external size; whereas normally you want to know how much space you have
> available, which is what ksize gives.
> 
> Didn't we have this discussion last time?

I was cced on that as far as I can tell.

The name objsize suggests the size of the object not the slab size.
If you want this then maybe call it kmem_cache_slab_size. SLUB 
distinguishes between obj_size which is the size of the struct that is 
used and slab_size which is the size of the object after alignment, adding 
debug information etc etc. See also slabinfo.c for a way to calculate 
theses sizes from user space.

If we really drop SLAB then we wont need this. SLUBs data structures are 
not opaque.
-
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/