[ofa-general] Re: opensm: a bug in heavy sweep? - no LFT re-configuration

[Sasha Khapyorsky]

On 20:04 Tue 24 Jul     , Sasha Khapyorsky wrote:
> On 07:56 Tue 24 Jul     , Eitan Zahavi wrote:
> > > On 20:59 Mon 23 Jul     , Eitan Zahavi wrote:
> > > > Hi Sasha, Hal,
> > > >  
> > > > I think I have an idea:
> > > >  
> > > > Since this is a specific switch that reported ChangeBit or Trap why 
> > > > can't we just qualify that there was no change in the switch setup?
> > > 
> > > The ChangeBit seems to be good start point - then OpenSM will 
> > > query all switch ports PortInfo anyway and if for all ports 
> > > PortState is <= INIT (and at least for one port it is = 
> > > INIT), it means that this switch was rebooted/reinitialized.
> > > 
> > > And for single port PortState drop to = INIT should indicate 
> > > reinitialization.
> > > 
> > > Seems correct?
> > Yes.
> > > 
> > > > We could send PortInfo, SwitchInfo,
> > > 
> > > SwitchInfo is queried at each light sweep, PortInfo's if 
> > > ChangeBit is set. Guess we are ok with it even now.
> > I will double check that...
> > Well - even setting one port state to INIT did not cause the switch to
> > be reconfigured.
> > Seems the code does not enforce this condition yet.
> > > 
> > > > LFT, MFT, SL2VL, VLArb, PKey queries
> > > > and make sure no change from previous state. Or we could simply 
> > > > enforce last state by sending it over again ...
> > > 
> > > I think we could want to re-read PKey tables in order to 
> > > preserve existing PKey indices and just to flush (overwrite 
> > > with new settings) LFT, MFT, SL2VL, VLArb tables. Reasonable?
> > Correct.
> 
> Ok, I will prepare patches. I think about separate patches for switches
> and ports. Also likely MFT should be handled separately, since we don't
> do incremental update there yet.

There is another case where data could be modified externally - when
master SM loses mastership, and after some time gets it back. Then data
should be flushed too. The patch shortly.

Sasha