[openib-general] APM support in openib stack

[Sean Hefty]

>3. in req_handler() we follow the same steps as we have done without APM..
>   i.e. create qpairs, change qp state to RTR and then  send REP.
>
>however, when trying to change state to RTR usinb ib_modify_qp() I get
>an error (-22).
>
>two info: same code will work if I pass alt_path as NULL or change the
>alt_path as primary path.
>
>I must be missing something here, I assume this basic APM feature works
>in RHEL4 update 4 distribtion
>of openib stack.

I added code to the ib_cm to handle APM, but haven't ever tested it myself.  I
believe others have used it successfully though.

What differences are there between the primary and alternate paths?  I.e. are
just the LIDs different, or are other values also different?

- Sean