[openib-general] *****SPAM***** [PATCH][RFC/v1][6/12] Add IPoIB (IP-over-InfiniBand) driver

[Hal Rosenstock]

On Thu, 2004-11-18 at 14:55, Roland Dreier wrote:
>     Hal> Is it also worth pointing out about multicast vis a vis IB ?
> 
> I didn't think so, because having to join a multicast group with the
> SA is conceptually similar to having to program a multicast hash table
> for an ethernet NIC or something like that.  So I don't think we have
> the sort of layering violation that we have for ARP -- the kernel
> already expects the driver to have to do something driver-specific to
> handle multicast.

Yes and no. While it is the appears the same in terms of the host (and
Linux already handles part of the problem, the semantics are not as rich
as they need to be for IB. I am referring to knowing whether to join as
a send only member, non member, or full member. (I think at least the
non member/full member distinction is important; I can live without send
only members as this is a minor optimization IMO although it does match
the idea of an IP multicast transmitter).

> On the other hand, if you have some suggested verbiage, I'm happy to
> include it.

If you think the idea above is correct, I will craft some verbiage.

-- Hal