Re: waitqueue lockdep annotation V3

From: Christoph Hellwig
Date: Tue Jul 17 2018 - 11:06:39 EST


On Tue, Jul 17, 2018 at 05:04:39PM +0200, Peter Zijlstra wrote:
> On Tue, Jul 17, 2018 at 04:24:37PM +0200, Christoph Hellwig wrote:
> > On Thu, Jul 12, 2018 at 12:17:53PM -0700, Davidlohr Bueso wrote:
> > > On Thu, 14 Dec 2017, Christoph Hellwig wrote:
> > >
> > >> Hi all,
> > >>
> > >> this series adds a strategic lockdep_assert_held to __wake_up_common
> > >> to ensure callers really do hold the wait_queue_head lock when calling
> > >> the unlocked wake_up variants. It turns out epoll did not do this
> > >> for a fairly common path (hit all the time by systemd during bootup),
> > >> so the second patch fixed this instance as well.
> > >
> > > I ran into these changes because of patch 1 getting rid of ep->lock. Is
> > > there any reason why this series was never picked up?
> >
> > I'd love to see this merged, but I never heard back about it.
>
> Seeing how it touched fs bits, I was expecting this to go through the
> vfs tree; was that not the intended target?

I don't really care which way it goes, although tip is more reliably
at picking up changes than the vfs tree..