[openib-general] [RFC] [PATCH 2/7] ib_multicast 2.6.20: add ib_multicast module to track join requests from the same port

[Or Gerlitz]

Michael S. Tsirkin wrote:
> Quoting r. Or Gerlitz <ogerlitz at voltaire.com>:
>> The ipoib change is a must to allow for user space consumers to 
>> join/leave groups whose MGID is "of IP multicast origin".

>> So one process can have its IP mulitcast traffic carried out by ipoib 
>> and another process can use librdmacm to join the same multicast group 
>> and attach a QP to the same MGID.

> And why the rush? Is the new module used at all yet?

Its not a rush its a move for enabling user space code that can offload 
IP Multicast. We have a library doing that which is coded over the gen1 
stack and is now in porting for the gen2 stack.

> Let's see it get some use before switching a basic component over.

This porting relies on Sean's work to allow for joining/leaving "IP 
Multicast" mcast groups from user space. And anyway, when you expose 
something to user space, you might not "see" the usage as it can be not 
an open source one.

Or.