Re: [PATCH net-next] rocker: Explicitly mark learned FDB entries as offloaded

[Ido Schimmel <idosch@nvidia.com>]

On Mon, Oct 31, 2022 at 09:08:23AM +0000, Vladimir Oltean wrote:
> On Mon, Oct 31, 2022 at 10:32:04AM +0200, Ido Schimmel wrote:
> > On Mon, Oct 31, 2022 at 09:59:22AM +0200, Ido Schimmel wrote:
> > > diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c b/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > > index 58cf7cc54f40..f5880d0053da 100644
> > > --- a/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > > +++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > > @@ -1828,12 +1828,14 @@ static void ofdpa_port_fdb_learn_work(struct work_struct *work)
> > >  	info.vid = lw->vid;
> > >  
> > >  	rtnl_lock();
> > > -	if (learned && removing)
> > > +	if (learned && removing) {
> > >  		call_switchdev_notifiers(SWITCHDEV_FDB_DEL_TO_BRIDGE,
> > >  					 lw->ofdpa_port->dev, &info.info, NULL);
> > > -	else if (learned && !removing)
> > > +	} else if (learned && !removing) {
> > > +		info.offloaded = true;
> > >  		call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_BRIDGE,
> > >  					 lw->ofdpa_port->dev, &info.info, NULL);
> > > +	}
> > >  	rtnl_unlock();
> > >  
> > >  	kfree(work);
> > 
> > Looking at it again, this is better:
> > 
> > diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c b/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > index 58cf7cc54f40..4d17ae18ea61 100644
> > --- a/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > +++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c
> > @@ -1826,6 +1826,7 @@ static void ofdpa_port_fdb_learn_work(struct work_struct *work)
> >  
> >         info.addr = lw->addr;
> >         info.vid = lw->vid;
> > +       info.offloaded = learned && !removing;
> >  
> >         rtnl_lock();
> >         if (learned && removing)
> > 
> > Will send another version tomorrow assuming no other comments.
> 
> It may also be an opportunity to not take rtnl_lock() if (!learned), and
> this will in turn simplify the condition to just "info.offloaded = !removing"?
> 
> Actually this elimination of useless work should be done at the level of
> ofdpa_port_fdb_learn(), if "flags" does not contain OFDPA_OP_FLAG_LEARNED.

OK, I have this as the first patch:

diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c b/drivers/net/ethernet/rocker/rocker_ofdpa.c
index 58cf7cc54f40..77ad09ad8304 100644
--- a/drivers/net/ethernet/rocker/rocker_ofdpa.c
+++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c
@@ -1821,19 +1821,16 @@ static void ofdpa_port_fdb_learn_work(struct work_struct *work)
        const struct ofdpa_fdb_learn_work *lw =
                container_of(work, struct ofdpa_fdb_learn_work, work);
        bool removing = (lw->flags & OFDPA_OP_FLAG_REMOVE);
-       bool learned = (lw->flags & OFDPA_OP_FLAG_LEARNED);
        struct switchdev_notifier_fdb_info info = {};
+       enum switchdev_notifier_type event;
 
        info.addr = lw->addr;
        info.vid = lw->vid;
+       event = removing ? SWITCHDEV_FDB_DEL_TO_BRIDGE :
+                          SWITCHDEV_FDB_ADD_TO_BRIDGE;
 
        rtnl_lock();
-       if (learned && removing)
-               call_switchdev_notifiers(SWITCHDEV_FDB_DEL_TO_BRIDGE,
-                                        lw->ofdpa_port->dev, &info.info, NULL);
-       else if (learned && !removing)
-               call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_BRIDGE,
-                                        lw->ofdpa_port->dev, &info.info, NULL);
+       call_switchdev_notifiers(event, lw->ofdpa_port->dev, &info.info, NULL);
        rtnl_unlock();
 
        kfree(work);
@@ -1865,6 +1862,9 @@ static int ofdpa_port_fdb_learn(struct ofdpa_port *ofdpa_port,
        if (!ofdpa_port_is_bridged(ofdpa_port))
                return 0;
 
+       if (!(flags & OFDPA_OP_FLAG_LEARNED))
+               return 0;
+
        lw = kzalloc(sizeof(*lw), GFP_ATOMIC);
        if (!lw)
                return -ENOMEM;