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To: Anton Blanchard <anton@ozlabs.org>, benh@kernel.crashing.org,
 paulus@samba.org, mahesh@linux.vnet.ibm.com, srikar@linux.vnet.ibm.com,
 hbathini@linux.vnet.ibm.com
From: Michael Ellerman <patch-notifications@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Subject: Re: powerpc/pseries: Use H_CLEAR_HPT to clear MMU hash table during
 kexec
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Date: Mon, 14 Nov 2016 23:17:27 +1100 (AEDT)
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On Sat, 2016-01-10 at 10:41:56 UTC, Anton Blanchard wrote:
> From: Anton Blanchard <anton@samba.org>
> 
> An hcall was recently added that does exactly what we need
> during kexec - it clears the entire MMU hash table, ignoring any
> VRMA mappings.
> 
> Try it and fall back to the old method if we get a failure.
> 
> On a POWER8 box with 5TB of memory, this reduces the time it takes to
> kexec a new kernel from from 4 minutes to 1 minute.
> 
> Signed-off-by: Anton Blanchard <anton@samba.org>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/5246adec59458b5d325b8e1462ea9e

cheers