Subject: Re: [PATCH] powerpc: During context switch, check before setting mm_cpumask

From: Benjamin Herrenschmidt <[email-masked]>
Date: Tue, 04 Oct 2016 10:58:14 +1100

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.