[openib-general] Re: Re: static rate encoding change support

[Michael S. Tsirkin]

Quoting r. Roland Dreier <rdreier at cisco.com>:
> Subject: Re: Re: static rate encoding change support
> 
>  > @@ -435,10 +443,16 @@ int mthca_query_qp(struct ib_qp *ibqp, s
>  >  		goto out;
>  >  	}
>  >  
>  > +	if (qp->transport == RC || qp->transport == UC)
>  > +		for (i = 1; i < dev->limits.num_ports; ++i)
>  > +			if ((err = mthca_update_rate(dev,i)))
>  > +				goto out;
> 
> I haven't read through all of this very carefully yet, but I'm
> wondering about this.  Why is it necessary to update the rates of all
> the ports on every query QP call?

I'm not sure. I assume we can just kill it.

> Any all of this seems like a whole lot of complexity for not much
> value.  If we really care about returning static rate from query QP,
> why not just store away the original state rate passed in through
> modify QP?

Hmm, seems like a waste of memory ... recoding back from hardware
seems cheaper - its global, not per QP. No?

-- 
Michael S. Tsirkin
Staff Engineer, Mellanox Technologies