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Message-ID: <521C3EE4.80801@bitfrost.no>
Date: Tue, 27 Aug 2013 07:53:40 +0200
From: Hans Petter Selasky <hps@bitfrost.no>
Organization: Bitfrost A/S
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To: Michael Tuexen <tuexen@freebsd.org>
Subject: Re: ARM network trouble after recent mbuf changes
References: <1377550636.1111.156.camel@revolution.hippie.lan>
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Cc: freebsd-arm <freebsd-arm@FreeBSD.org>, Andre Oppermann <andre@freebsd.org>
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On 08/27/13 00:38, Michael Tuexen wrote:
> I did some tests with a small program. Having in struct pkthdr 64 bit entities
> results in a 64 bit alignment when used in struct mbuf. Using __packed
> for struct mbuf, removes the padding.


Hi,

Maybe you could use __aligned(8) instead, and account for the extra 
padding on all platforms? Packed has other disadvantages on ARM 
platforms when accessing the structures, like that non-aligned access is 
possible, and that it is sometimes slower than aligned access.

--HPS