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Subject: Re: [PATCH] powerpc: During context switch, check before setting
 mm_cpumask
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
 Anton Blanchard <anton@ozlabs.org>, paulus@samba.org, mpe@ellerman.id.au,
 npiggin@gmail.com, cyrilbur@gmail.com
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Cc: linuxppc-dev@lists.ozlabs.org,
 "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
From: Balbir Singh <bsingharora@gmail.com>
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Date: Tue, 4 Oct 2016 11:20:16 +1100
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On 04/10/16 10:58, Benjamin Herrenschmidt wrote:
> On Tue, 2016-10-04 at 10:25 +1100, Balbir Singh wrote:
>> I think this makes sense, in fact I think in the longer term we can
>> even use __set_bit() reorder-able version since we have a sync
>> coming out of schedule(). The read side for TLB flush can use a RMB
> 
> No, that wouldn't be atomic vs. other threads accessing the same
> bitmap.

Somethings distorted my thought process. Thanks!

Balbir Singh.