From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [patch sungem] improved locking
Date: Wed, 29 Nov 2006 11:19:34 +1100
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To: David Miller <davem@davemloft.net>
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On Tue, 2006-11-28 at 15:43 -0800, David Miller wrote:

> At least in theory the atomic + any necessary memory barriers
> would be cheaper than the extra PIO read we need otherwise.

Yes, IO reads are generally the worst case scenarios even on machines
with fairly slow locks.

Ben.