Date: Thu, 22 Nov 2007 19:24:12 -0600
From: Robert Hancock <hancockr@shaw.ca>
Subject: Re: [RFC] Documentation about unaligned memory access
In-reply-to: <fa.U+CIv4JClOmn6KppLkEOSk7RW0Y@ifi.uio.no>
To: Daniel Drake <dsd@gentoo.org>
Cc: linux-kernel@vger.kernel.org, davem@davemloft.net
Message-id: <47462BBC.2000206@shaw.ca>
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Daniel Drake wrote:
> Being spoilt by the luxuries of i386/x86_64 I've never really had a good
> grasp on unaligned memory access problems on other architectures and decided
> it was time to figure it out. As a result I've written this documentation
> which I plan to submit for inclusion as
> Documentation/unaligned_memory_access.txt
> 
> Before I do so, any comments on the following?

...

> You may be wondering why you have never seen these problems on your own
> architecture. Some architectures (such as i386 and x86_64) do not have this
> limitation, but nevertheless it is important for you to write portable code
> that works everywhere.

Also, x86 doesn't prohibit unaligned accesses, but I believe they have a 
significant performance cost and are best avoided where possible.

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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