On Fri, Nov 20, 2015 at 03:36:40PM +1000, David Gwynne wrote: > IFF_OACTIVE means the hardware ring is full, not if it is busy. > > perhaps a better check is to see whether there are pending packets > on the send queue? > > i could also argue we dont need the check at all, but this is less > of a semantic change. > > ok? >
OK I added this check in the initial commit of trunk(4) more than 10 years ago. I don't remember a particular reason - there wasn't even a production use yet. I initially wrote trunk to use it for failover on some firewalls, but it was not going into production before it was committed to OpenBSD. So the reason for the flag might just be a historical one: back in the days, I heard that 10 years is a long time in IT, there was not much reference about implementing such a "cloner" correctly. I must have looked at vlan(4) or bridge(4) and decided that it was the way to do. I mean, before mpi@, working in the network stack was tough and very different: you didn't ask, never refered to any documentation, just relied on the traditions and repeated what was done by the BSD heroes in the past. Reyk > Index: if_trunk.c > =================================================================== > RCS file: /cvs/src/sys/net/if_trunk.c,v > retrieving revision 1.124 > diff -u -p -r1.124 if_trunk.c > --- if_trunk.c 20 Nov 2015 05:33:54 -0000 1.124 > +++ if_trunk.c 20 Nov 2015 05:35:07 -0000 > @@ -296,7 +296,7 @@ trunk_port_create(struct trunk_softc *tr > return (ENOSPC); > > /* New trunk port has to be in an idle state */ > - if (ifp->if_flags & IFF_OACTIVE) > + if (!ifq_empty(&ifp->if_snd)) > return (EBUSY); > > /* Check if port has already been associated to a trunk */ --
