Re: [PATCH v2 4/4] lockdep: Assign a lock_class per gendisk used for wait_for_completion()

From: Byungchul Park
Date: Mon Oct 23 2017 - 03:04:46 EST


On Sun, Oct 22, 2017 at 11:36:30PM -0700, Christoph Hellwig wrote:
> On Mon, Oct 23, 2017 at 08:53:35AM +0900, Byungchul Park wrote:
> > On Fri, Oct 20, 2017 at 07:44:51AM -0700, Christoph Hellwig wrote:
> > > The Subject prefix for this should be "block:".
> > >
> > > > @@ -945,7 +945,7 @@ int submit_bio_wait(struct bio *bio)
> > > > {
> > > > struct submit_bio_ret ret;
> > > >
> > > > - init_completion(&ret.event);
> > > > + init_completion_with_map(&ret.event, &bio->bi_disk->lockdep_map);
> > >
> > > FYI, I have an outstanding patch to simplify this a lot, which
> > > switches this to DECLARE_COMPLETION_ONSTACK. I can delay this or let
> > > you pick it up with your series, but we'll need a variant of
> > > DECLARE_COMPLETION_ONSTACK with the lockdep annotations.
> >
> > Hello,
> >
> > I'm sorry for late.
> >
> > I think your patch makes block code simpler and better. I like it.
> >
> > But, I just wonder if it's related to my series.
>
> Because it shows that we also need a version of DECLARE_COMPLETION_ONSTACK
> the gets passed an explicit lockdep map. And because if it was merged
> through a different tree it would create a conflict.
>
> > Is it proper to add
> > your patch into my series?
>
> Sure.

I will add yours at the next spin.

Thank you.

BTW, to all...

Any additional opinions about these patches?