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From: Michael Neuling <mikey@neuling.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH] fixes for the SLB shadow buffer 
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Date: Thu, 02 Aug 2007 19:28:15 +1000
Message-ID: <30559.1186046895@neuling.org>
Cc: linuxppc-dev@ozlabs.org, will_schmidt@vnet.ibm.com,
	Paul Mackerras <paulus@samba.org>
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> On Thu, 2007-08-02 at 19:03 +1000, Michael Neuling wrote:
> > > 
> > > Ok, that was missing from your description :-)
> > 
> > Sorry... so ditch the barriers? 
> 
> As you like. The reason why you can ditch them is purely because you
> know for sure that the only case the firmware will access those shadows
> from another CPU is that one and it happens to be just right. What are
> the chances that in the future, FW will do something different and
> nobody will "fix" the code ?

Yep, I might chat to some PHYP guys and see what they think.

> Considering that eieios are fairly cheap and it's not a very hot code
> path as far as I can tell, I'd rather keep them.

OK.  I'll keep them in for now and submit an optimisation patch later if
need be.

Mikey