Re: [PATCH rdma-next v1 1/6] IB/uverbs: Allow CQ moderation with modify CQ

Jason Gunthorpe
2017-10-30T15:52:36Z

On Mon, Oct 30, 2017 at 05:28:15PM +0200, Leon Romanovsky wrote:
> > + * ib_modify_cq - Modifies moderation params of the CQ
> > + * @cq: The CQ to modify.
> > + * @cq_count: number of CQEs that will trigger an event
> > + * @cq_period: max period of time in usec before triggering an event
> > + *
> > + */
> > +int ib_modify_cq(struct ib_cq *cq, u16 cq_count, u16 cq_period);
>
> I see it differently, this is extendable version of modify_cq, which is
> going to benefit all other users who will decide to extend it.

The only reason we have these goofy 'thick' APIs like modify_qp is
because people said they needed a very high rate of qp modifications
and could not tolerate the performance downside of a dis-aggregated
API.

I don't think CQ falls into that reasoning, so it should be
dis-aggregated.

Many things in verbs are terrible examples of how to make APIs, we
should not just blindly copy things..

Jason