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Date: Tue, 17 Jan 2017 12:53:21 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [RFC PATCH] membarrier: handle nohz_full with expedited thread
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On Tue, Jan 17, 2017 at 04:55:22AM +0100, Frederic Weisbecker wrote:

[ . . . ]

> In fact due to the complexity involved, I have to ask first if we
> really need this feature.  Typically nohz_full workloads don't want to
> be disturbed at all, so do we have real and significant usecases of CPU
> isolation workloads that want to be concerned by this membarrier so much
> that they can tolerate some random IRQ?

I believe that we need to explore the options for implementing it and
to -at- -least- have a patch ready, even if that patch doesn't go
upstream immediately.

							Thanx, Paul