From owner-freebsd-hackers@FreeBSD.ORG  Thu Aug 23 20:45:37 2012
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Date: Thu, 23 Aug 2012 13:45:37 -0700
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From: Adrian Chadd <adrian@freebsd.org>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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Cc: freebsd-hackers@freebsd.org,
	Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>,
	Mitya <mitya@cabletv.dp.ua>, freebsd-net@freebsd.org
Subject: Re: Replace bcopy() to update ether_addr
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You can't assume the ethernet addresses will be aligned.

For wifi headers you're definitely going to have at least one address
be non-dword aligned, even if the header itself is dword aligned.

The whole point of using a macro is so it becomes really easy to
change the copy type at compile time. Otherwise I'll have to go
through the code, find all the (CPU intensive/stalling) places where
those 6 byte copies are occuring and replace them.



Adrian