> From: Linus Torvalds <[email protected]> > Sent: Tuesday, May 15, 2018 10:22 > To: Dexuan Cui <[email protected]> > > On Mon, May 14, 2018 at 8:02 PM Dexuan Cui <[email protected]> wrote: > > > If you're OK with the below fix (not tested yet), I'll submit a patch for > > it: > > > --- a/kernel/time/tick-broadcast.c > > +++ b/kernel/time/tick-broadcast.c > > @@ -616,6 +616,10 @@ static void tick_handle_oneshot_broadcast(struct > clock_event_device *dev) > > now = ktime_get(); > > /* Find all expired events */ > > for_each_cpu(cpu, tick_broadcast_oneshot_mask) { > > +#ifndef CONFIG_SMP > > + if (cpumask_empty(tick_broadcast_oneshot_mask)) > > + break; > > +#endif > > I'm certainly ok with this. It's hacky, but maybe being explicitly hacky is > good to "document" this gotcha. > > And I really do agree that this special UP case is nasty nasty and much too > subtle, and I hope that some day we won't care about UP at all, and maybe > kill it, or maybe just make for_each_cpu() generate the extra code to have > the actual same semantics as the SMP case. > > Linus
Thanks! I submitted the patch just now: https://lkml.org/lkml/2018/5/15/866 Thanks, -- Dexuan
