On Wed, Jul 08, 2015 at 04:16:43PM -0700, sfel...@gmail.com wrote: > From: Scott Feldman <sfel...@gmail.com> > > Signed-off-by: Scott Feldman <sfel...@gmail.com> > --- > Documentation/networking/switchdev.txt | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/Documentation/networking/switchdev.txt > b/Documentation/networking/switchdev.txt > index c5d7ade..b864e47 100644 > --- a/Documentation/networking/switchdev.txt > +++ b/Documentation/networking/switchdev.txt > @@ -279,8 +279,18 @@ and unknown unicast packets to all ports in domain, if > allowed by port's > current STP state. The switch driver, knowing which ports are within which > vlan L2 domain, can program the switch device for flooding. The packet > should > also be sent to the port netdev for processing by the bridge driver. The > -bridge should not reflood the packet to the same ports the device flooded. > -XXX: the mechanism to avoid duplicate flood packets is being discuseed. > +bridge should not reflood the packet to the same ports the device flooded, > +otherwise there will be duplicate packets on the wire. > + > +To avoid duplicate packets, the device/driver can mark a packet as already
I wonder if 'should' or 'may' would be clearer than 'can'. > +forwarded using skb->offload_fwd_mark. The same mark is set on the device > +ports in the domain using dev->offload_fwd_mark. If the > skb->offload_fwd_mark > +is non-zero and matches the forwarding egress port's dev->skb_mark, the > kernel > +will drop the skb right before transmit on the egress port, with the > +understanding that the device already forwarded the packet on same egress > port. > +The driver can use switchdev_port_fwd_mark_set() to set a globally unique > mark > +for port's dev->offload_fwd_mark, based on the port's parent ID (switch ID) > and > +a group ifindex. > > It is possible for the switch device to not handle flooding and push the > packets up to the bridge driver for flooding. This is not ideal as the > number > -- > 1.7.10.4 > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
