From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next v4 1/4] ieee802154: add generic header
 handling routines
Date: Tue, 04 Mar 2014 17:20:25 -0500 (EST)
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From: "Phoebe Buckheister" <phoebe.buckheister@itwm.fraunhofer.de>
Date: Tue, 4 Mar 2014 23:16:31 +0100

> I see some value in being able to memcpy() to/from those fields directly
> when building/reading headers, but I also think that not having to do
> endianness conversion everywhere for a struct that cannot ever be a valid
> header as is outweighs this.

Why have an intermediate copy when that's not necessary at all?  It
seems like pure overhead to be.

Furthermore, cpu's have byte-shifting load and store instructions
which will be used if you make use of the 'p' versions of the endian
swap functions, such as cpu_to_le16p().

So it's going to cost basically nothing.