[ofa-general] Re: [PATCH] opensm: notify master SM with trap 144 (not finished)

[Sasha Khapyorsky]

Hi Hal,

On 16:27 Tue 28 Oct     , Hal Rosenstock wrote:
> On Sat, Oct 25, 2008 at 4:01 PM, Sasha Khapyorsky <sashak at voltaire.com> wrote:
> >
> > When entering standby state (after discovery) notify master SM about us.
> > In case when SMA doesn't support trap sending (specifically trap 144 on
> > PortInfo:CapabilityMask change - isSM bit, example is current ConnectX
> > firmware - 2.5.0) this is only way to notify the current master SM that
> > another SM is running.
> 
> So is the trap sent unconditionally (since there's no way of knowing
> whether the SMA supports this or not) ? Is the only downside the extra
> Trap/TrapRepress when the SMA does support this ?

It is not unconditional. There is such code at beginning of
osm_send_trap144():

	/* don't bother with sending trap when SMA supports this */
	if (!local &&
	    pi->capability_mask&(IB_PORT_CAP_HAS_TRAP|IB_PORT_CAP_HAS_CAP_NTC))
		return 0;

> Seems to me that the right fix is to the Connect-X SMA.

Agree. But it is not there yet.

> Also, what happens once the Connect-X SMA is fixed ? Does this code persist ?

Then osm_send_trap144(..., 0) will do nothing following
PortInfo:CapabilityMask. And actually if the problem will become
obsolete we can remove this call safely.

Sasha