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Date: Sat, 29 Jul 2017 12:51:54 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Nicholas Piggin <npiggin@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
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Subject: Re: [RFC PATCH v2] membarrier: expedited private command
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On Sat, Jul 29, 2017 at 07:48:56PM +1000, Nicholas Piggin wrote:
> On Sat, 29 Jul 2017 19:45:43 +1000
> Nicholas Piggin <npiggin@gmail.com> wrote:
> 
> > hmm, we might be able to restrict iteration
> > to mm_cpumask(current->mm), no? 
> 
> Oh that's been discussed too. I'll read back over it too.

Right, the main problem is that some architectures (arm64 for instance,
although Will is looking at it) don't use mm_cpumask() at all.

Other architectures (PPC for instance) only ever set bits.