Re: [regression] __tick_program_event of hpet is stuck

[Thomas Gleixner <tglx@linutronix.de>]

On Tue, 9 Sep 2008, Frans Pop wrote:

> On Tuesday 09 September 2008, Thomas Gleixner wrote:
> > It's nothing to worry about. I out the WARN_ON() there to get some
> > information about the validation of min_delta_ns and to see in which
> > range this happens.
> 
> Ah, OK. A WARN_ON is perhaps a bit heavy for that, unless you actually
> want to be flooded with reports :-)

Yes, I wanted that. Some new debug outputs are usually
ignored. WARN_ONs are not.

> In my case it prevented me from running the kernel on other boxes than the
> laptop because I feared some possibly important issue.

That was not my intention.
 
> Also, a single line can easily be filtered out from logcheck reports while
> doing the same for WARN_ONs is much harder and even not advisable.
> 
> > I'm going to remove the WARN_ON() and just keep the information that
> > we need to increase the min_delta_ns value for safe operation.
> 
> Sounds like a plan; have already done so locally.
> 
> Here are some results I've got so far. You can see reboots and supend
> to RAMs. Maximum observed value on the HP 2510p is now 80000 with the
> system mostly idle or in light use.

Ok. That's still a reasonable range.

> I also tried getting these on my desktop by switching the clocksource from
> tsc to hpet, but that did not result in any output (identical x86_64 kernel).

I have not a single machine where this shows up, but I really wanted
to get some data. It worked :)

Thanks,

	tglx