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Date: Mon, 23 Apr 2018 18:44:25 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Diego Viola <diego.viola@gmail.com>
Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, len.brown@intel.com,
        rui.zhang@intel.com, "Rafael J. Wysocki" <rjw@rjwysocki.net>
Subject: Re: Experiencing freezes with kernel 4.16.3 on a desktop with E5500
 CPU (bisect included)
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On Mon, Apr 23, 2018 at 05:58:01PM +0200, Peter Zijlstra wrote:
> Thomas, we could not find the de-rate stuff, but the above can be
> simplified; what happens is:
> 
> 	cs->flags |= UNSTABLE;
> 	schedule_work(&watchdog_work)
> 	  kthread_run(clocksource_watchdog_kthread)

Also, Thomas, do you remember why we spawn a short running kthread from
a work ? Can't we simply run the whole thing from the worker thread?

> 	    __clocksource_watchdog_kthread()
> 	      if (cs->flags & UNSTABLE)
> 	        __clocksource_change_rating()
> 	   clocksource_select()
>