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Date: Fri, 9 May 2008 02:16:14 +0300
From: "Tomas Winkler" <tomasw@gmail.com>
To: "Johannes Berg" <johannes@sipsolutions.net>
Subject: Re: iwlwifi and tx info in skb->cb
Cc: "Ron Rindjunsky" <ron.rindjunsky@intel.com>,
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On Fri, May 9, 2008 at 1:30 AM, Johannes Berg <johannes@sipsolutions.net> wrote:
>
>  > I've just scanned the thread that was explaining why is this necessary
>  > I will read it more carefully... I have just feeling that all this
>  > wlan stuff just fits very awkwardly into current networking stack.
>
>  That's not really related to wireless at all, if you want to do
>  zero-copy IO then you need to checksum when the stuff hits the wire
>  which means out of hardware buffers, which some hardware (including
>  802.11) doesn't support so you need to copy, nothing wireless specific
>  here :)
>

The FCS/CRS checksum of the wireless packet is performed in the HW but
why should I care about IP layer?

>  Anyway, with the changes davem and I are making to actually save the
>  *extra* copy we should be doing well. That's where you want to look for
>  improvements.

This is just for the bridging case, isn't it?

Tomas