Re: [PATCH 0/3] Add NETIF_F_HW_BRIDGE feature
From: Jiri Pirko
Date: Sat Aug 24 2019 - 03:42:44 EST
Sat, Aug 24, 2019 at 01:25:02AM CEST, f.fainelli@xxxxxxxxx wrote:
>On 8/22/19 12:07 PM, Horatiu Vultur wrote:
>> Current implementation of the SW bridge is setting the interfaces in
>> promisc mode when they are added to bridge if learning of the frames is
>> In case of Ocelot which has HW capabilities to switch frames, it is not
>> needed to set the ports in promisc mode because the HW already capable of
>> doing that. Therefore add NETIF_F_HW_BRIDGE feature to indicate that the
>> HW has bridge capabilities. Therefore the SW bridge doesn't need to set
>> the ports in promisc mode to do the switching.
>Then do not do anything when the ndo_set_rx_mode() for the ocelot
>network device is called and indicates that IFF_PROMISC is set and that
>your network port is a bridge port member. That is what mlxsw does AFAICT.
>As other pointed out, the Linux bridge implements a software bridge by
>default, and because it needs to operate on a wide variety of network
>devices, all with different capabilities, the easiest way to make sure
>that all management (IGMP, BPDU, etc. ) as well as non-management
>traffic can make it to the bridge ports, is to put the network devices
>in promiscuous mode. If this is suboptimal for you, you can take
>shortcuts in your driver that do not hinder the overall functionality.
>> This optimization takes places only if all the interfaces that are part
>> of the bridge have this flag and have the same network driver.
>> If the bridge interfaces is added in promisc mode then also the ports part
>> of the bridge are set in promisc mode.
>> Horatiu Vultur (3):
>> net: Add HW_BRIDGE offload feature
>> net: mscc: Use NETIF_F_HW_BRIDGE
>> net: mscc: Implement promisc mode.
>> drivers/net/ethernet/mscc/ocelot.c | 26 ++++++++++++++++++++++++--
>> include/linux/netdev_features.h | 3 +++
>> net/bridge/br_if.c | 29 ++++++++++++++++++++++++++++-
>> net/core/ethtool.c | 1 +
>> 4 files changed, 56 insertions(+), 3 deletions(-)