Re: [Xen-devel] [PATCH 5/8] xen/sched: use keyhandler locks when dumping data to console

[Jürgen Groß <jgross@xxxxxxxx>]

On 19.02.20 15:31, Dario Faggioli wrote:
> On Thu, 2020-02-13 at 13:54 +0100, Juergen Gross wrote:
> > Instead of using the normal locks use the keyhandler provided
> > trylocks
> > with timeouts. This requires a special primitive for the scheduler
> > lock.
> So, FWIW, I tend to agree with Andrew on the general aspects of this.
> I.e., I personally don't think that the added complexity, however small
> one may judge it to be, is worth it... I'm not even sure not using
> regular locks is really an improvement.
>
> When you mentioned, in your other mail, that having something like this
> would have saved a lot of reboots during the development of core-
> scheduling, would _just_ disabling the watchdog have achieved the same?
No.

I was hit by the keyhandler just waiting for a lock which would never
be freed. This blocked printing information for cpus I would have
liked to see (chances were about 50% in my case that the "interesting"
cpu had a higher cpu number than the locked one).

> Anyway, I've had a look at this patch. _If_ we go with this new lock
> thing, the modifications to the scheduler code done here seems fine to
> me.
Thanks.


Juergen

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel