Re: [PATCH] tools/memory-model: remove rb-dep, smp_read_barrier_depends, and lockless_dereference

From: Alan Stern
Date: Wed Feb 21 2018 - 10:00:28 EST


On Fri, 16 Feb 2018, Paul E. McKenney wrote:

> On Fri, Feb 16, 2018 at 05:22:55PM -0500, Alan Stern wrote:
> > Since commit 76ebbe78f739 ("locking/barriers: Add implicit
> > smp_read_barrier_depends() to READ_ONCE()") was merged for the 4.15
> > kernel, it has not been necessary to use smp_read_barrier_depends().
> > Similarly, commit 59ecbbe7b31c ("locking/barriers: Kill
> > lockless_dereference()") removed lockless_dereference() from the
> > kernel.
> >
> > Since these primitives are no longer part of the kernel, they do not
> > belong in the Linux Kernel Memory Consistency Model. This patch
> > removes them, along with the internal rb-dep relation, and updates the
> > revelant documentation.
> >
> > Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
>
> I queued this, but would welcome an update that addressed Akira's
> feedback as appropriate.

Is it too late to send a v2 of this patch? I didn't want to do it
before now because the issue raised by Andrea wasn't settled. (Some
could claim that it still isn't fully settled...)

Alan