Re: Possible issue with commit 4961b6e11825?

From: Frederic Weisbecker
Date: Mon Dec 07 2015 - 14:01:35 EST


On Fri, Dec 04, 2015 at 03:20:22PM -0800, Paul E. McKenney wrote:
> Hello!
>
> Are there any known issues with commit 4961b6e11825 (sched: core: Use
> hrtimer_start[_expires]())?
>
> The reason that I ask is that I am about 90% sure that an rcutorture
> failure bisects to that commit. I will be running more tests on
> 3497d206c4d9 (perf: core: Use hrtimer_start()), which is the predecessor
> of 4961b6e11825, and which, unlike 4961b6e11825, passes a 12-hour
> rcutorture test with scenario TREE03. In contrast, 4961b6e11825 gets
> 131 RCU CPU stall warnings, 132 reports of one of RCU's grace-period
> kthreads being starved, and 525 reports of one of rcutorture's kthreads
> being starved. Most of the test runs hang on shutdown, which is no
> surprise if an RCU CPU stall is happening at about that time.

I have no idea what the issue is but maybe you have the RCU stall backtrace
somewhere?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/