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Subject: Re: [PATCH] Remove barriers from the SLB shadow buffer update
From: Josh Boyer <jwboyer@linux.vnet.ibm.com>
To: Michael Neuling <mikey@neuling.org>
In-Reply-To: <3992.1187938717@neuling.org>
References: <3992.1187938717@neuling.org>
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Date: Thu, 23 Aug 2007 15:36:20 -0500
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On Fri, 2007-08-24 at 16:58 +1000, Michael Neuling wrote:
> After talking to an IBM POWER hypervisor design and development (PHYP)
> guy, there seems to be no need for memory barriers when updating the SLB
> shadow buffer provided we only update it from the current CPU, which we
> do.
> 
> Also, these guys see no need in the future for these barriers.

Does this result in a significant performance gain?  I'm just curious.

josh