Re: [PATCH 0/4] per anon_vma lock and turn anon_vma rwsem lock to rwlock_t

Davidlohr Bueso
2013-11-02T03:19:04Z

On Fri, 2013-11-01 at 11:55 -0700, Linus Torvalds wrote:
> On Fri, Nov 1, 2013 at 11:47 AM, Michel Lespinasse <walken@google.com> wrote:
> >
> > Should copy Andrea on this. I talked with him during KS, and there are
> > no current in-tree users who are doing such sleeping; however there
> > are prospective users for networking (RDMA) or GPU stuff who want to
> > use this to let hardware directly copy data into user mappings.
>
> Tough.
>
> I spoke up the first time this came up and I'll say the same thing
> again: we're not screwing over the VM subsystem because some crazy
> user might want to do crazy and stupid things that nobody sane cares
> about.
>
> The whole "somebody might want to .." argument is just irrelevant.

Ok, I was under the impression that this was something already in the
kernel and hence "too late to go back". Based on the results I'm
definitely in favor of the whole rwlock conversion.

Thanks,
Davidlohr