[ovs-dev] [PATCH 04/18] lib: Add igmp generic snooping library bits

[Ben Pfaff]

On Tue, May 20, 2014 at 07:26:31PM -0300, Flavio Leitner wrote:
> On Tue, May 20, 2014 at 02:38:08PM -0700, Ben Pfaff wrote:
> > On Fri, Apr 11, 2014 at 06:34:09PM -0300, Flavio Leitner wrote:
> > > This patch adds generic IPv4 library code to deal with
> > > igmp snooping that is implemented in follow-up patches.
> > > 
> > > Signed-off-by: Cong Wang <amwang at redhat.com>
> > > Signed-off-by: Daniel Borkmann <dborkman at redhat.com>
> > > Acked-by: Thomas Graf <tgraf at redhat.com>
> > > Signed-off-by: Flavio Leitner <fbl at redhat.com>

...

> OK, I can fix those issues and send a v2. I will wait for
> feedbacks on the remaining patches to address all them together.

That makes sense.

> > How much of a common case do you expect multicast lookups to be?  Do
> > you think it will be worth trying to RCUify this, to avoid taking a
> > lock on the read path?
> 
> Enough to worth to do that.  There was no RCU when this work has
> started and rwlock is more simple to implement and review. 

rwlock is definitely easier to review.  It's fine to get this in
before worrying about RCU, by the way; I just wanted you to start
thinking about it.

> Anyway, it's on my ToDo list, along with adding support for IGMPv3 and IPv6.

OK, that answers another question ;-)