Subject: Re: MMIO and gcc re-ordering (Was: [PATCH] [POWERPC] Improve (in|out)_beXX() asm code)

From: Benjamin Herrenschmidt <[email-masked]>
Date: Fri, 23 May 2008 18:47:32 -0400

On Fri, 2008-05-23 at 16:14 -0500, Scott Wood wrote:

> As Trent pointed out, if you change to eieio in the accessors, that'd 
> require drivers to also use mmiowb() before spin_unlock(), which fewer 
> drivers currently do.

No, this is a totally different issue. And we keep track of the need
for a sync in spin_unlock already.

Ben.