Re: [PATCH 04/19] sched: Prepare for Core-wide rq->lock

[Don Hiatt]

On Thu, Apr 29, 2021 at 1:48 PM Josh Don <joshdon@xxxxxxxxxx> wrote:
>
> On Wed, Apr 28, 2021 at 9:41 AM Don Hiatt <dhiatt@xxxxxxxxxxxxxxxx> wrote:
> >
> > I'm still seeing hard lockups while repeatedly setting cookies on qemu
> > processes even with
> > the updated patch. If there is any debug you'd like me to turn on,
> > just let me know.
> >
> > Thanks!
> >
> > don
>
> Thanks for the added context on your repro configuration. In addition
> to the updated patch from earlier, could you try the modification to
> double_rq_lock() from
> https://lkml.kernel.org/r/CABk29NuS-B3n4sbmavo0NDA1OCCsz6Zf2VDjjFQvAxBMQoJ_Lg@xxxxxxxxxxxxxx
> ? I have a feeling this is what's causing your lockup.
>
> Best,
> Josh

Hi Josh,

I've been running Aubrey+Peter's patch (attached) for almost 5 hours
and haven't had a single issue. :)

I'm running a set-cookie script every 5 seconds on the two VMs (each
vm is running
'sysbench --threads=1 --time=0 cpu run' to generate some load in the vm) and
I'm running two of the same sysbench runs on the HV while setting cookies
every 5 seconds.

Unless I jinxed us it looks like a great fix. :)

Let me know if there is anything else you'd like me to try. I'm going
to leave the tests running
and see what happens. I update with what I find.

Thanks!

don

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