Re: Threaded irqs + 100% CPU RT task = RCU stall

[Thomas Gleixner]

On Wed, 6 Mar 2013, Paul Gortmaker wrote:
> So, I guess the question is, whether we want to try and make the system
> fail in a more meaningful way -- kind of like the rt throttling message
> does - as it lets users know they've hit the wall?  Something watching

That Joe Doe should have noticed the throttler message, which came
before the stall, shouldn't he?

> for kstat_incr_softirqs traffic perhaps?  Or other options?

The rcu stall detector could use the softirq counter and if it did not
change in the stall period print: "Caused by softirq starvation" or
something like that.

Thanks,

	tglx


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