[openib-general] Re: Re: libibverbs and max inline data

[Michael S. Tsirkin]

Quoting r. James Lentini <jlentini at netapp.com>:
> Subject: Re: Re: libibverbs and max inline data
> 
> 
> On Sun, 22 May 2005, Roland Dreier wrote:
> 
> >   Michael> Hi!  I tried to figure out how much inline data a qp can
> >   Michael> support, to know what max_inline_data value to put in the
> >   Michael> qp.  However, there doesnt seem to exist a way to do
> >   Michael> that, currently.
> >
> >I think you're right.
> >
> >   Michael> Maybe the driver should be changed to trim
> >   Michael> max_inline_data to the maximum possible value?
> >
> >Yes, that would probably make sense.  In a sense that's what the
> >kernel driver already does -- it always clips the max_inline_data
> >request from the consumer down to 0.
> 
> ib[v]_create_qp should return an error when an unsupported inline data 
> size is requested.

Why is it important? The user could always check the max_inline_data
returned and close the qp if thats too small, but I dont see
many users doing this - inline data is mainly a tuning opportunity.

> >Independent of that we could add a field to the device properties
> >struct (and implement ibv_query_device() for userspace).
> >
> >- R.

-- 
MST - Michael S. Tsirkin