Re: [PATCH v2 0/9] Remove spin_unlock_wait()

From: Ingo Molnar
Date: Sat Jul 08 2017 - 04:43:34 EST

* Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote:

> On Fri, Jul 07, 2017 at 10:31:28AM +0200, Ingo Molnar wrote:
> [ . . . ]
> > In fact I'd argue that any future high performance spin_unlock_wait() user is
> > probably better off open coding the unlock-wait poll loop (and possibly thinking
> > hard about eliminating it altogether). If such patterns pop up in the kernel we
> > can think about consolidating them into a single read-only primitive again.
> I would like any reintroduction to include a header comment saying exactly
> what the consolidated primitive actually does and does not do. ;-)
> > I.e. I think the proposed changes are doing no harm, and the unavailability of a
> > generic primitive does not hinder future optimizations either in any significant
> > fashion.
> I will have a v3 with updated comments from Manfred. Thoughts on when/where
> to push this?

Once everyone agrees I can apply it to the locking tree. I think PeterZ's was the
only objection?

> The reason I ask is if this does not go in during this merge window, I need
> to fix the header comment on spin_unlock_wait().

Can try it next week after some testing - let's see how busy things get for Linus
in the merge window?