Re: [RFC PATCH v1.9 00/14] livepatch: hybrid consistency model

From: Josh Poimboeuf
Date: Tue Apr 05 2016 - 10:35:05 EST


On Tue, Apr 05, 2016 at 04:24:33PM +0200, Miroslav Benes wrote:
> On Mon, 4 Apr 2016, Josh Poimboeuf wrote:
>
> > > I'd add a fake signal facility for sleeping non-migrated tasks. This
> > > would accelerate a migration to a new universe. We have it in kgraft for
> > > quite some time and it worked out great. See
> > > lkml.kernel.org/r/1430739625-4658-9-git-send-email-jslaby@xxxxxxx which
> > > went with Jiri's kgraft-on-klp patch set. See also Oleg's reply as it is
> > > important (I changed kgraft implementation according to that).
> >
> > Ok, I'll look into sending a fake signal to remaining tasks.
>
> Oh, do not worry about this one. I can prepare a patch once we discuss and
> review the rest. I think you have a lot on your plate even now.
>
> There are several options how to do it. I think it would be nice not send
> a fake signal immediately. So we can...
>
> 1. do it after some time of waiting, or
>
> 2. we can have a knob in sysfs for an admin to send a fake signal if he
> does not want to wait anymore, or
>
> 3. (and this is crazy one) we can trace the progress of a migration and
> when there is none for several iterations we can send a signal

Ok, thanks, I'll skip it for now. We do need to think about the options
and I do have a full plate already.

I might also procrastinate with the patch module removal patch, since
that's another separate piece which might need more discussion.

--
Josh