if_tap unaligned access problem
Mike Silbersack
silby at silby.com
Mon May 2 16:12:56 PDT 2005
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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