Re: [PATCH v11 3/5] sched/core: uclamp: Propagate system defaults to root group

From: Joel Fernandes
Date: Tue Jul 16 2019 - 11:46:33 EST


On Tue, Jul 16, 2019 at 10:34 AM Patrick Bellasi
<patrick.bellasi@xxxxxxx> wrote:
>
> On 15-Jul 18:42, Michal Koutnà wrote:
> > On Mon, Jul 08, 2019 at 09:43:55AM +0100, Patrick Bellasi <patrick.bellasi@xxxxxxx> wrote:
> > > +static void uclamp_update_root_tg(void)
> > > +{
> > > + struct task_group *tg = &root_task_group;
> > > +
> > > + uclamp_se_set(&tg->uclamp_req[UCLAMP_MIN],
> > > + sysctl_sched_uclamp_util_min, false);
> > > + uclamp_se_set(&tg->uclamp_req[UCLAMP_MAX],
> > > + sysctl_sched_uclamp_util_max, false);
> > > +
> > > + cpu_util_update_eff(&root_task_group.css);
> > > +}
> > cpu_util_update_eff internally calls css_for_each_descendant_pre() so
> > this should be protected with rcu_read_lock().
>
> Right, good catch! Will add in v12.
>

Hopefully these can catch it in the near future!
https://lore.kernel.org/rcu/20190715143705.117908-1-joel@xxxxxxxxxxxxxxxxx/T/#t