Re: [PATCH v0.9.1 3/6] sched/umcg: implement UMCG syscalls

From: Peter Zijlstra
Date: Mon Nov 29 2021 - 13:50:29 EST


On Sat, Nov 27, 2021 at 01:45:20AM +0100, Thomas Gleixner wrote:
> On Fri, Nov 26 2021 at 22:59, Peter Zijlstra wrote:
> > On Fri, Nov 26, 2021 at 10:08:14PM +0100, Thomas Gleixner wrote:
> >> > + if (timo)
> >> > + hrtimer_sleeper_start_expires(&timeout, HRTIMER_MODE_ABS);
> >> > +
> >> > + freezable_schedule();
> >>
> >> You can replace the whole hrtimer foo with
> >>
> >> if (!schedule_hrtimeout_range_clock(timo ? &timo : NULL,
> >> tsk->timer_slack_ns,
> >> HRTIMER_MODE_ABS,
> >> tsk->umcg_clock)) {
> >> ret = -ETIMEOUT;
> >> break;
> >> }
> >
> > That seems to loose the freezable crud.. then again, since we're
> > interruptible, that shouldn't matter. Lemme go do that.
>
> We could add a freezable wrapper for that if necessary.

I should just finish rewriting that freezer crap and then we can delete
it all :-) But I don't think that's needed in this case, as long as
we're interruptible we'll pass through the signal path which has a
try_to_freezer() in it.