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Date: Tue, 3 Jun 2014 08:06:04 +1000
From: Anton Blanchard <anton@samba.org>
To: Michael Neuling <mikey@neuling.org>
Subject: Re: [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs
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 <1401692223-28337-2-git-send-email-mikey@neuling.org>
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Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>,
 Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org
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Hi,

> This patch enables POWER8 doorbell IPIs on powernv.
> 
> Since doorbells can only IPI within a core, we test to see when we
> can use doorbells and if not we fall back to XICS.  This also enables
> hypervisor doorbells to wakeup us up from nap/sleep via the LPCR
> PECEDH bit.
> 
> Based on tests by Anton, the best case IPI latency between two
> threads dropped from 894ns to 512ns.
> 
> Signed-off-by: Michael Neuling <mikey@neuling.org>

Thanks Mikey!

Tested-by: Anton Blanchard <anton@samba.org>

Anton