To: Manfred Spraul <manfred@colorfullife.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: NS83820 2.6.0-test5 driver seems unstable on IA64
From: Andi Kleen <ak@muc.de>
Date: Fri, 26 Sep 2003 17:14:57 +0200
In-Reply-To: <zU7D.2Ji.27@gated-at.bofh.it> (Manfred Spraul's message of
 "Fri, 26 Sep 2003 08:20:17 +0200")
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Manfred Spraul <manfred@colorfullife.com> writes:

> David wrote:
>
>>Fine, then we should have something like an rx_copybreak scheme in
>>the ns83820 driver too.
>>
> Is that really the right solution? Add a full-packet copy to every driver?
> IMHO the fastest solution would be to copy only the ip & tcp headers,
> and keep the rest as it is. And preferable in the network core, to
> avoid having to copy&paste that into every driver.

One problem is that you still have an unaligned->aligned copy to user space
in recvmsg (the user buffer is usually aligned and the network payload 
will be unaligned). And that will be very slow.

-Andi
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