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Date: Sat, 25 Jun 2016 10:55:38 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Richard Cochran <richardcochran@gmail.com>
cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [patch V3 19/22] timer: Forward wheel clock whenever possible
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On Fri, 24 Jun 2016, Richard Cochran wrote:

> On Fri, Jun 24, 2016 at 02:32:19PM -0000, Thomas Gleixner wrote:
> > @@ -809,6 +815,12 @@ static void tick_nohz_restart_sched_tick
> >  	tick_do_update_jiffies64(now);
> >  	cpu_load_update_nohz_stop();
> >  
> > +	/*
> > +	 * Clear the timer idle flag, so we avoid IPIs on remote queueing and
> > +	 * the clock forward checks in the enqueue path.
> > +	 */
> > +	timer_clear_idle();
> 
> Since function calls timer_clear_idle() already ...
>
> >  	calc_load_exit_idle();
> >  	touch_softlockup_watchdog_sched();
> >  	/*
> > @@ -1025,6 +1037,7 @@ void tick_nohz_idle_exit(void)
> >  		tick_nohz_stop_idle(ts, now);
> >  
> >  	if (ts->tick_stopped) {
> > +		timer_clear_idle();
> >  		tick_nohz_restart_sched_tick(ts, now);
> >  		tick_nohz_account_idle_ticks(ts);
> >  	}
> 
> ... there is no need to call timer_clear_idle() here.

Indeed.