[openib-general] Questions about SMI

[Hal Rosenstock]

On Tue, 2004-10-12 at 13:57, Roland Dreier wrote:
>     Hal> No, it's not broken (of course depending on one's definition)
>     Hal> and yes, this can be bypassed and is on my TODO list. I have
>     Hal> been focusing more on functionality right now.
> 
> Oh, OK, I see.  smi_send_smp() is what actually generates the response
> and sends it back.  Sorry I didn't follow the code far enough.  By the
> way, what do you mean by "bypassing" this?

The choice is to either change the routine names so not just smi or smp
or to pick off the 2 classes (LR SMPs and PerfMgt) and just handle them
a little more "directly". That's all.

>     Roland> Finally, what's the plan for handling device-specific
>     Roland> things like Tavor-generated MADs (to recap: when Tavor
>     Roland> needs to send a trap to the SM, the trap shows up as a
>     Roland> receive on the local QP0 with source LID 0; this MAD needs
>     Roland> to be forwarded to the SM)?
> 
>     Hal> How important is this ? Things seem to run fine without it
>     Hal> right now as far as I can tell.
> 
> Yes, things will usually work fine since SM traps are not used for
> things like subnet discovery, so it's not that important for now.
> However, if something happens to cause the Tavor to start sending out
> a trap, it will continue to send traps forever (since the trap is not
> being forwarded to anyone who will generate a trap repress).  

I'm not sure the traps get out on the wire right now so it may just be a
local issue right now...

> Also, I don't think it's possible to pass compliance testing without this.

Yes, there is at least one cause Trap to be generated at DUT and send
TrapRepress to DUT case in the compliance suite if I recall correctly.

> In any case, my question is really about the architecture to handle
> this, since it can't be done by registering an agent 

I'm missing something here. Do these traps come in as normal receives
(to the SMA) ? If so, can't they be identified from other receives (e.g.
SLID = 0 (perhaps other parameters)) ? 

If they don't come in as normal receives, can they be "made into"
receives ?

> (someone,probably the low-level driver, needs to look at SMPs before agent
> dispatch and check the SLID to decide what to do with it).

Thanks.

-- Hal