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From: Kumar Gala <galak@kernel.crashing.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Subject: Re: [PATCH 11/16] powerpc/mm: Add SMP support to no-hash TLB handling
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Date: Mon, 15 Dec 2008 16:19:47 -0600
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On Dec 15, 2008, at 3:18 PM, Benjamin Herrenschmidt wrote:

> On Mon, 2008-12-15 at 15:10 -0600, Kumar Gala wrote:
>
>> Hmm.. are you mixing the two different locking needs together?  The  
>> is
>> locking of ivax vs tlbwe and there is locking around multiple "msgs"
>> on the bus.  I know for us we can have any # of ivax's on the bus,  
>> but
>> only one tlbsync.
>
> I'm purely talking about the later. Right now I only issue one ivax +
> one tlbsycn anyway but I was thinking about having _tlbivax_bcast  
> take a
> count for small ranges, but I would still lock the whole thing because
> some impl I know of don't like multiple ivax coliding form different
> sources neither.

Ok.  Lets use MMU_FTR_LOCK_BCAST_TLB_OPS and have a comment about  
locking because bus implementations cant handle multiple ivax and/or  
multiple syncs.

- k