Messages in this thread | | | Date | Fri, 19 Feb 2016 09:33:43 -0800 | From | "Paul E. McKenney" <> | Subject | Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17 |
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On Thu, Feb 18, 2016 at 08:13:18PM -0800, John Stultz wrote: > On Thu, Feb 18, 2016 at 7:56 PM, Ross Green <rgkernel@gmail.com> wrote: > > Well a bonus extra! > > Kept everything running and there was another stall. > > So i have included the demsg output for perusal. > > > > Just to clear things up there is no hotplug involved in this system. > > It is a standard Pandaboard ES Ti4460 two processor system. > > I use this for testing as a generic armv7 processor, plus can keep it > > just running along for testing for a long time. the system has a total > > of 23-25 process running on average. Mainly standard daemons. There is > > certainly no heavy processing going on. I run a series of benchmarks > > that are cpu intensive for the first 20 miinutes after boot and then > > just leave it idle away. checking every so often to see how it has > > gone. > > As mentioned I have observed these stalls going back to 3.17 kernel. > > It will often take up to a week to record such a stall. I will > > typically test every new release kernel, so the -rc? series will get > > around a weeks testing. > > Sorry. Kind of hopping in a bit late here. Is this always happening > with just the pandaboard? Or are you seeing this on different > machines? > > Have you tried enabling CONFIG_DEBUG_TIMEKEEPING just in case > something is going awry there?
Excellent point -- timekeeping issues have caused this sort of issue in the past.
Ross, on your next test, could you please enable CONFIG_DEBUG_TIMEKEEPING as John suggests?
Thanx, Paul
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