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Date:   Thu, 3 May 2018 19:54:56 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc:     Mike Galbraith <efault@gmx.de>,
        Matt Fleming <matt@codeblueprint.co.uk>,
        Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        Michal Hocko <mhocko@suse.com>
Subject: Re: cpu stopper threads and load balancing leads to deadlock
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On Thu, May 03, 2018 at 10:18:50AM -0700, Paul E. McKenney wrote:
> > +	if (per_cpu(rcu_cpu_started, cpu))
> 
> I would log a non-splat dmesg the first time this happened, just for my
> future sanity, but otherwise looks fine.  I am a bit concerned about
> calls to rcu_cpu_starting() getting sprinkled all through the code.
> Or am I being excessively paranoid?

Don't think so, but lets first see if this at all works. If not we'll
need to figure out something else anyway.