Re: rcu: enable rcu_normal_after_boot by default for RT

From: Sebastian Andrzej Siewior
Date: Thu Nov 08 2018 - 10:52:36 EST


On 2018-11-01 16:02:35 [-0700], Paul E. McKenney wrote:
> > The forcing of an expedited grace period is an expensive and very
> > RT-application unfriendly operation, as it forcibly preempts all running
> > tasks on CPUs which are preventing the gp from expiring.
> >
> > By default, as a policy decision, disable the expediting of grace
> > periods (after boot) on configurations which enable PREEMPT_RT_FULL.
> >
> > Suggested-by: Luiz Capitulino <lcapitulino@xxxxxxxxxx>
> > Signed-off-by: Julia Cartwright <julia@xxxxxx>
> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
>
> In case it matters:
>
> Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
>
> Alternatively, any reason that I should not pull this into -rcu?
because we don't have CONFIG_PREEMPT_RT_FULL yet.
> Thanx, Paul

Sebastian