Re: [PATCH] clocksource: disable irq when holding watchdog_lock.

[Paul E. McKenney]

On Tue, Oct 17, 2023 at 08:49:46AM +0200, Thomas Gleixner wrote:
> On Mon, Oct 16 2023 at 16:03, Paul E. McKenney wrote:
> > On Mon, Oct 16, 2023 at 11:47:55PM +0200, Thomas Gleixner wrote:
> >> That said, this whole clocksource watchdog mess wants a proper
> >> overhaul. It has become a pile of warts and duct tape by now and after
> >> staring at it long enough there is no real reason to run it in a timer
> >> callback anymore. It just can move into delayed work and the whole
> >> locking problem can be reduced to the clocksource_mutex and some well
> >> thought out atomic operations to handle the mark unstable case. But
> >> that's a different story and not relevant for curing the problem at
> >> hand.
> >
> > Moving the code to delayed work seems quite reasonable.
> >
> > But Thomas, you do understand that the way things have been going for
> > the clocksource watchdog, pushing it out to delayed work will no doubt
> > add yet more hair on large busy systems, right?  Yeah, yeah, I know,
> > delayed work shouldn't be any worse than ksoftirqd.  The key word of
> > course being "shouldn't".  ;-)
> 
> Yes, I'm aware of that. I still think it's worth at least to try it.

OK, good.  And again, agreed.

							Thanx, Paul