On Thu, Oct 14, 2010 at 11:20 AM, Hefty, Sean <sean.he...@intel.com> wrote:
>> > Export the mad snooping capability to user space clients
>> > through the existing umad interface.  This will allow
>> > users to capture MAD data for debugging, plus it allows
>> > for services to act on MAD traffic that occurs.
>>
>> Should it also be noted that snooping of RMPP'd MADs occurs at the
>> reassembled packet level with the last header being indicated ?
>
> I thought that the mad layer ending up reporting snooped MADs before 
> reassembly and after segmentation.  It's been a while since I've used madeye, 
> but that's what I remember.  I guess I'll find out during testing and make 
> whatever adjustments are necessary,

Yes, you're right; I recall this now.

> but I agree that this should be documented.
>
> On a side note, while writing up this patch, it looks like madeye handles the 
> data portion of sent RMPP MADs incorrectly.  It doesn't reference the data 
> portion (beyond the RMPP/MAD headers) correctly.  See the snoop_send_handler 
> for how I think this needs to be handled.
>
>> > diff --git a/include/rdma/ib_user_mad.h b/include/rdma/ib_user_mad.h
>> > index d6fce1c..0c40861 100644
>> > --- a/include/rdma/ib_user_mad.h
>> > +++ b/include/rdma/ib_user_mad.h
>> > @@ -165,10 +165,36 @@ struct ib_user_mad {
>> >  typedef unsigned long __attribute__((aligned(4))) packed_ulong;
>> >  #define IB_USER_MAD_LONGS_PER_METHOD_MASK (128 / (8 * sizeof (long)))
>> >
>> > +enum {
>> > +       IB_UMAD_QP0,
>> > +       IB_UMAD_QP1,
>> > +       IB_UMAD_SNOOP = 0x80,
>> > +       IB_UMAD_SNOOP_QP0 = IB_UMAD_SNOOP & IB_UMAD_QP0,
>> > +       IB_UMAD_SNOOP_QP1 = IB_UMAD_SNOOP & IB_UMAD_QP1
>> > +};
>>
>> typos above: s.b. | r.t. &
>
> yep - thanks
>
>> > + * @qpn - Queue pair number; must be 0 or 1.  If the upper bit of the
>> qpn
>> > + *   is set to 1, then the registration will be set to snoop traffic
>> > + *   over that QP.
>>
>> Should this take half the qpn space or be two specific values ?
>
> Two specific values is probably better.  Note that the umad interface 
> specifies the qpn using 8-bits, so we're definitely limited on the qpns that 
> we could ever support.  I know there's been discussion about possibly adding 
> more reserved QPs, so I'm not sure what the best two values to reserve would 
> be.

Me neither. Maybe the top two values ?

-- Hal

>
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to