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Date: Sun, 29 Oct 2017 17:51:06 -0700
From: Ram Pai <linuxram@us.ibm.com>
To: Paul Mackerras <paulus@ozlabs.org>
Cc: linuxppc-dev@lists.ozlabs.org,
 "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: Re: [PATCH 00/16] Remove hash page table slot tracking from linux PTE
Reply-To: Ram Pai <linuxram@us.ibm.com>
References: <20171027040833.3644-1-aneesh.kumar@linux.vnet.ibm.com>
 <20171027043430.GA27483@fergus.ozlabs.ibm.com>
 <adf2d270-29df-701f-206e-0d8a35084e47@linux.vnet.ibm.com>
 <20171028223532.GA5587@ram.oc3035372033.ibm.com>
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On Mon, Oct 30, 2017 at 09:04:17AM +1100, Paul Mackerras wrote:
> On Sat, Oct 28, 2017 at 03:35:32PM -0700, Ram Pai wrote:
> > 
> > I like the idea of not tracking the slots at all. It is something the
> > guest should not be knowing or tracking.
> 
> Why do you say that?

'slot' is a internal mechanism used by the hash table to accelerate
mapping an address to a hash-page.  If the hash-table implementation
choose to use a different mechanism to accelerate the mapping, it can't
because that mechanism is baked into the logic of all the consumers.

RP