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Date: Thu, 16 Nov 2017 09:58:05 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
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Subject: Re: [PATCH RFC v3 3/6] sched/idle: Add a generic poll before enter
 real idle path
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On Thu, 16 Nov 2017, Peter Zijlstra wrote:

> On Wed, Nov 15, 2017 at 11:03:08PM +0100, Thomas Gleixner wrote:
> > If I understand the problem correctly then he wants to avoid the heavy
> > lifting in tick_nohz_idle_enter() in the first place, but there is already
> > an interesting quirk there which makes it exit early. 
> 
> Sure. And there are people who want to do the same for native.
> 
> Adding more ugly and special cases just isn't the way to go about doing
> that.
> 
> I'm fairly sure I've told the various groups that want to tinker with
> this to work together on this. I've also in fairly significant detail
> sketched how to rework the idle code and idle predictors.
> 
> At this point I'm too tired to dig any of that up, so I'll just keep
> saying no to patches that don't even attempt to go in the right
> direction.

That's why I said: But lets not proliferate that. I'd rather see that go
away.

And yes, the VM folks should talk to those who are trying to solve similar
problems for native (embedded/mobile).

Thanks,

	tglx