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Date: Tue, 30 Sep 2008 12:36:08 -0500
From: Christoph Lameter <cl@linux-foundation.org>
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To: Richard Kennedy <richard@rsk.demon.co.uk>
CC: penberg <penberg@cs.helsinki.fi>, mpm <mpm@selenic.com>,
       linux-mm <linux-mm@kvack.org>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] slub: reduce total stack usage of slab_err & object_err
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Richard Kennedy wrote:

> Yes, using vprintk is better but you still have this path :
> ( with your patch applied)
> 
> 	object_err -> slab_bug(208) -> printk(216)
> instead of 
> 	object_err -> slab_bug_message(8) -> printk(216)
> 
> unfortunately the overhead for having var_args is pretty big, at least
> on x86_64. I haven't measured it on 32 bit yet.

Really 208 bytes for a va arg parameter declaration? I expected it to be
simply a null terminated pointer list.