Re: [PATCH] nohz_full: Make sched_should_stop_tick() more conservative

[Chris Metcalf]

On 4/4/2016 3:36 PM, Rik van Riel wrote:
> > > On Fri, 2016-04-01 at 15:42 -0400, Chris Metcalf wrote:
> > > > On arm64, when calling enqueue_task_fair() from
> > > > migration_cpu_stop(),
> > > > we find the nr_running value updated by add_nr_running(), but the
> > > > cfs.nr_running value has not always yet been
> > > > updated.  Accordingly,
> > > > the sched_can_stop_tick() false returns true when we are
> > > > migrating a
> > > > second task onto a core.
> > > > Correct this by using rq->nr_running instead of rq-
> > > > > cfs.nr_running.
> > > > This should always be more conservative, and reverts the test to
> > > > the
> > > > form it had before commit 76d92ac305f2 ("sched: Migrate sched to
> > > > use
> > > > new tick dependency mask model").
> [...]
>
> Patch gets my:
>
> Acked-by: Rik van Riel <riel@xxxxxxxxxx>

Thanks!  Whose tree should this go through: Frederic, PeterZ, Ingo?
Do any of you have any concerns with it?

--
Chris Metcalf, Mellanox Technologies
http://www.mellanox.com