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Date:   Tue, 5 Nov 2019 00:43:29 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Scott Wood <swood@redhat.com>
cc:     Peter Zijlstra <peterz@infradead.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] timers/nohz: Update nohz load even if tick already
 stopped
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References: <20191028150716.22890-1-frederic@kernel.org>  <20191029100506.GJ4114@hirez.programming.kicks-ass.net>  <52d963553deda810113accd8d69b6dffdb37144f.camel@redhat.com>  <20191030133130.GY4097@hirez.programming.kicks-ass.net>
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On Mon, 4 Nov 2019, Thomas Gleixner wrote:
> On Fri, 1 Nov 2019, Scott Wood wrote:
> > On Wed, 2019-10-30 at 14:31 +0100, Peter Zijlstra wrote:
> > > Oh argh! that's a bit radical of the remote tick. The normal tick runs
> > > just fine on idle CPUs, so lets mirror that.
> > > 
> > > How's this then?
> 
> ....
>  
> > 
> > Needs to be tick_nohz_tick_stopped_cpu(cpu)
> > 
> > After fixing that, I get:
> > 
> > [    7.439068] WARNING: CPU: 20 PID: 7 at /home/root/linux/kernel/sched/core.c:3681 sched_tick_remote+0x132/0x150
> 
> So I'm going to apply Scotts patch if nobody comes up with a better idea
> until tomorrow.

As Peter pointed out to me privately we should rather go and analyze the
real thing instead of just applying duct tape.

/me drops the patch again.