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Subject: Re: [PATCH] powerpc: During context switch, check before setting
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Balbir Singh <bsingharora@gmail.com>, Anton Blanchard <anton@ozlabs.org>,
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Date: Tue, 04 Oct 2016 10:58:14 +1100
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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.

Ben.