Re: if_tap unaligned access problem

From: Mike Silbersack (silby_at_silby.com)
Date: 05/03/05

  • Next message: Sten Spans: "Re: if_tap unaligned access problem" 
    Date: Mon, 2 May 2005 18:12:44 -0500 (CDT)
To: Bruce M Simpson <bms@spc.org>

    On Thu, 28 Apr 2005, Bruce M Simpson wrote:

    > jmg's suggestion of bringing in the NetBSD patches to allow the entire
    > network stack to be compiled with unaligned accesses (for those platforms
    > which support it) is interesting because it can simplify or eliminate
    > some of the acrobatics needed in network drivers to deal with the mbuf
    > alignment.

    I'm too lazy to benchmark, but I suspect that having the ethernet code
    shift the packet backwards by two bytes after it strips off the ethernet
    header is going to be faster than requiring ip_input to allocate a new
    mbuf for each received packet.

    Such a change would also ensure that we don't break all the other
    protocols that jmg didn't touch in his patch.

    Mike "Silby" Silbersack
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