[ofa-general] [RFC] XRC -- make receiving XRC QP independent of any one user process

[Jack Morgenstein]

On Thursday 03 January 2008 17:49, Tang, Changqing wrote:
> Another issue I have after thinking about the interface more.
> 
> Rank A is the sender, rank B and C are two ranks on a remote node. At first, B creates the
> receiving QP and make connection to A and register the QP number for receiving. And A gets
> the receiving QP nubmer from B.  After some communication between A and B, B decides to close
> the connection, and unregister the QP number. Then A and C want to talk, so A tell C the
> receiving QP number, C tries to register the QP number.
> 
> I wonder at the time when C tries to register the QP number, the receiving QP has been
> destroyed by the kernel, since when B unregister the QP number, the reference count becomes
> zero, and kernel will cleanup it.
> 
> Am I right ?

Yes.  However, C will get an error when it tries to register with that QP, and can return the
error to A.

- Jack