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

[Arlin Davis]

Roland Dreier wrote:

>    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...
>  
>
I guess this is no worse than sockets consuming a FD with every new 
connection.

> - R.
>
>  
>