Re: [PATCH 3/4] infiniband-diags: properly resolve node guids

Ira Weiny
2011-07-08T22:29:53Z

On Fri, 8 Jul 2011 14:59:01 -0700
Hal Rosenstock <hal-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org> wrote:

> On 7/8/2011 5:50 PM, Jason Gunthorpe wrote:
> > On Fri, Jul 08, 2011 at 05:42:38PM -0400, Hal Rosenstock wrote:
> >
> >> Should the request just be a GET rather than GET_TABLE and avoid this
> >> check ? I don't think multiple nodes can register with same Node GUID,
> >> can they ? Also, I think it makes eliminates this check and the missing
> >> 0 check.
> >
> > Multiport HCAs should (and do..) show up with multiple node
> > records. There is one node record per end port, not per node. This is
> > why using node GUID as an end port identifier is a bad choice.

It is _not_ a bad choice if you are looking for a "node".

>
> Before this patch, it did used to use the port GUID for this.

The point of this patch is to do the right thing when the user is requesting a node they want information about. The next step is to accept NodeDescription and use that from the NodeRecord as a key.

>
> > However, you could use GET and look at the return code to disambiguate
> > no records/one record/many records.
>
> Yes, that was getting at (and that there was no check for no records
> returned with the get table code).

Ok, that is a bug. We should check for no records.

As for multiple records, I left that for a future patch which would query all of those ports.

Ira

>
> -- Hal
>
> > Jason
> >
>

--
Ira Weiny
Math Programmer/Computer Scientist
Lawrence Livermore National Lab
925-423-8008
weiny2-i2BcT+NCU+M@public.gmane.org