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Subject: Re: [PATCH] powerpc: inline ppc64_runlatch_off
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Anton Blanchard <anton@samba.org>
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Date: Fri, 06 Aug 2010 16:25:49 +1000
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On Fri, 2010-08-06 at 15:56 +1000, Anton Blanchard wrote:
> Unfortunately we still need to prevent continual writes to it with a per thread
> flag because on some CPUs a write to the SPR in low priority mode will stall
> another SMT thread. So we could get rid of the cpu feature comparison but
> we would still need the thread bit check (or perhaps replace it with a per cpu
> variable). 

remind me why we need to do that runlatch thing on these CPUs at all ?

Cheers,
Ben.