Re: [lkp] [fs] df4c0e36f1: NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]

Dave Hansen
2015-11-02T17:39:46Z

On 11/02/2015 01:32 AM, Andrey Ryabinin wrote:
> And the major factor here is number 2.
>
> In your dmesg:
> [ 67.891156] rbtree testing -> 570841 cycles
> [ 88.609636] augmented rbtree testing
> [ 116.546697] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s!
> [swapper/0:1]
>
>
> I've tried to reproduce this, and got this:
> [ 0.693574] rbtree testing -> 15513 cycles
> 570841/15513 = 36x times faster.
>
> [ 1.159450] augmented rbtree testing -> 23675 cycles
> [ 1.864996]
> It took less than a second, meanwhile in your case it didn't finish in
> 22 seconds.
>
> This makes me think that your host is overloaded and the problem is on
> your side.

It's probably just a matter of putting some cond_resched()s in the test
code.