[openib-general] Re: uVerbs and multiple cq_event support?

[Roland Dreier]

    Arlin> Hi Roland, I have a question about uverbs
    Arlin> cq_events. Currently, uverbs has one event (fd) handle that
    Arlin> processes all CQ events. You mentioned earlier that you
    Arlin> would possibly add support for more CQ events. Are you
    Arlin> thinking one per CQ, or limiting to a small number like one
    Arlin> per processor? If the thinking is NOT one per CQ then it
    Arlin> may be somewhat restricitive to user applications that have
    Arlin> multple connections with many CQs to process.

My thinking was a small number, to match the 1.2 IBA spec's idea of
having a fixed number of CQ event handlers available and also to match
the capabilities of MSI-X interrupts.  However, the idea of being able
to dynamically create an arbitrary number of CQ event FDs is
interesting.  I need to think about how feasible this is.

    Arlin> If the thinking is one per CQ then is fd's the way to go
    Arlin> since we can have 1000's of CQs?

I don't know of a different way to implement this...

 - R.