[openib-general] RE: Re: RFC: e2e credits

[Sean Hefty]

>What does the flow_control parameter in ib_cm and rdma_cma conn_param do?
>If that's what it is, I think its easier to just add API to ib verbs
>making it possible to implement it than invent a device-specific way
>to do it per driver.

As far as I can tell, it doesn't do anything.  Flow control is a parameter of
the IB CM REQ/REP messages, so are exposed to the user.

I don't see how a user can make use of it in any practical way, however.  It
isn't used to configure anything on the QP from what I can tell.  This is why I
mentioned that the only use I can think of is for an app to change its
algorithms based on whether this value is set or not, but I have a hard time
imagining an app doing so.

- Sean