[ofa-general] [RFC] [PATCH 0/5 v2] rdma/cm: add ability to specify type of service

[Sean Hefty]

>It's not a requirement to wait for the QoS determination of the SA
>before issuing the SA PR requests.

It sounds like you're suggesting that the end nodes just automatically gather
and print the capabilities of the SA.  (Why limit it to QoS only then?)  An
administrator could run a separate tool to gather this information, rather than
it being done on all nodes automatically.  If the QoS determination is tied into
the behavior of the PR queries, then I think you end up either queuing the
requests or responses somewhere.

>Failover is pretty straightforward. The same query is made when SM LID changes.

Yes - but existing paths that are in use may now suddenly provide or no longer
provide QoS.

>Will the QoS code handle the new error status code which suggests a
>different QoSClass or is it currently being handled like other errors
>? Guess that could be a separate patch.

This would be a separate patch, and is left up to each ULP at the moment.  For
ipoib, I used the TClass, so the new QoS fields are not an issue.  For the
rdma_cm, the QoS info is set by the user when using IPv4 addressing, so they
would need to take appropriate action.

- Sean