Re: [patch-rt] hotplug, hrtimer: Migrate expired/deferred timers during cpu offline

[Mike Galbraith <efault@gmx.de>]

On Thu, 2017-08-17 at 19:17 +0200, Sebastian Andrzej Siewior wrote:
> On 2017-08-17 18:50:42 [+0200], To Mike Galbraith wrote:
> > __remove_hrtimer() shouldn't be required because it has been done
> > already. It should be enough to just list_splice() one list to the
> > other and raise the softirq afterwards.
> 
> Mike, can you check this please:

Done, works.

> diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
> index 55839ff2bba6..4b9264e0d363 100644
> --- a/kernel/time/hrtimer.c
> +++ b/kernel/time/hrtimer.c
> @@ -1802,6 +1802,11 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
>  		 */
>  		enqueue_hrtimer(timer, new_base);
>  	}
> +#ifdef CONFIG_PREEMPT_RT_BASE
> +	list_splice_tail(&old_base->expired, &new_base->expired);
> +	if (!list_empty(&new_base->expired))
> +		raise_softirq_irqoff(HRTIMER_SOFTIRQ);
> +#endif
>  }
>  
>  int hrtimers_dead_cpu(unsigned int scpu)