Re: [GIT PULL clocksource] Clocksource watchdog commits for v5.15

From: Thomas Gleixner
Date: Thu Aug 12 2021 - 09:46:49 EST


On Wed, Aug 11 2021 at 17:01, Paul E. McKenney wrote:
> This pull request contains a single change that prevents clocksource
> watchdog testing on systems with HZ < 100, thus preventing the integer
> underflow that can occur on leisurely HZed systems. This has been
> posted to LKML:
>
> https://lore.kernel.org/lkml/20210721212755.GA2066078@paulmck-ThinkPad-P17-Gen-1/

So with HZ < 100 .mult overflows, but why not simply adjusting the
mult, shift value to be

.mult = TICK_NSEC,
.shift = 0,

which is effectively the same as

.mult = TICK_NSEC << 8,
.shift = 8,

Hmm?

Thanks,

tglx