Re: [PATCH] prinkt/nbcon: Add a scheduling point to nbcon_kthread_func().

[Derek Barbosa]

On Thu, Jun 20, 2024 at 12:18:37PM -0500, Andrew Halaney wrote:
> Acked-by: Andrew Halaney <ahalaney@xxxxxxxxxx>
> Tested-by: Andrew Halaney <ahalaney@xxxxxxxxxx>
> 
> This survived a bunch of tests that normally would cause some lockups
> etc in PREEMPT_VOLUNTARY systems. I can see that the nbcon thread successfully
> migrated NUMA nodes etc during periods of overwhelming the console backlog
> successfully, which without this would not work prior.
> 
> Thanks!

I'm going to second Andrew's observed results here. With the original
reproducer of calling LTP pty03 && pty06 in a while loop, plus invoking
stress-ng with --timeout 60000s && --numa 64, there were no problems with the
nbcon thread migrating NUMA nodes and no panic(s) with 
kernel.softlockup_panic = 1

This was observed on an nproc == 128 machine.

Thanks! :-) 

Acked-by: Derek Barbosa <debarbos@xxxxxxxxxx>
Tested-by: Derek Barbosa <debarbos@xxxxxxxxxx>