Re: [PATCH v14 24/25] sched: early boot clock

From: Pavel Tatashin
Date: Thu Jul 19 2018 - 10:17:16 EST


On Thu, Jul 19, 2018 at 6:40 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Tue, Jul 17, 2018 at 10:22:10PM -0400, Pavel Tatashin wrote:
>
> > diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
> > index 0e9dbb2d9aea..7a8a63b940ee 100644
> > --- a/kernel/sched/clock.c
> > +++ b/kernel/sched/clock.c
> > @@ -202,7 +202,15 @@ static void __sched_clock_gtod_offset(void)
> >
> > void __init sched_clock_init(void)
> > {
> > + unsigned long flags;
> > +
> > sched_clock_running = 1;
> > +
> > + /* Adjust __gtod_offset for contigious transition from early clock */
> > + local_irq_save(flags);
> > + sched_clock_tick();
> > + local_irq_restore(flags);
> > + __sched_clock_gtod_offset();
>
> I think we want to keep __sched_clock_gtod_offset() inside the IRQ
> disabled region.

Fixed.

>
> And I just looked at my patch:
>
> https://lkml.kernel.org/r/20180626090003.GA2458@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>
> and that had a comment about how we wanted to set the gtod offset
> _before_ setting sched_clock_running, yet here you do it the other way
> around. Hmm?

Fixed, and added your comment.

Thank you,
Pavel