[openib-general] ib_cancel_mad and the CM

[Sean Hefty]

Libor Michalek wrote:

  >   No, what I'm saying is that having the CM assigns the wr_id, and then
> having the mad code actually executes the cancel, is a problem. There is
> nothing to prevent multiple mad consumers from using the same wr_id, in
> fact I would assume it. If you want to use wr_id as a handle that the
> mad layer can use to lookup a message, then the mad layer needs to be
> where the wr_id is assigned/generated. Either that or you need some other
> identifier which you can use to cancel messages.

The scope of the MAD is limited by the mad_agent, which is defined per 
consumer of the MAD layer, so the re-use of wr_id's between consumers 
isn't an issue.

>   In my opinion using pointers in the wr_id is bad for other reasons,
> this is a problem with the scope of a certain value. The assignment and
> cancel execution have to occur in the same scope.

Whether the MAD context is a pointer or an index into a table, the 
current problem is still the same.

- Sean