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Date: Sat, 3 May 2008 15:35:21 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Roland Dreier <rdreier@cisco.com>, "Moore\, Eric" <Eric.Moore@lsi.com>,
       linux-kernel@vger.kernel.org
Subject: Re: HELP:  Is writeq an atomic operation??
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> > I don't have an authoritative answer, but I can say that I coded
> > drivers/infiniband/hw/mthca and .../mlx4 assuming that writeq() is
> > atomic in the sense that you say, and no one has reported any problems.
> > 
> 
> If you're not under lock you're screwed on a 32-bit platform.

So what cycles does an MMX, SSE or double float store generate on the
bus ?

Alan