Message ID | 20210322235152.268695-1-olteanv@gmail.com (mailing list archive) |
---|---|
Headers | show |
Series | Better support for sandwiched LAGs with bridge and DSA | expand |
Hello: This series was applied to netdev/net-next.git (refs/heads/master): On Tue, 23 Mar 2021 01:51:41 +0200 you wrote: > From: Vladimir Oltean <vladimir.oltean@nxp.com> > > Changes in v4: > - Added missing EXPORT_SYMBOL_GPL > - Using READ_ONCE(fdb->dst) > - Split patches into (a) adding the bridge helpers (b) making DSA use them > - br_mdb_replay went back to the v1 approach where it allocated memory > in atomic context > - Created a br_switchdev_mdb_populate which reduces some of the code > duplication > - Fixed the error message in dsa_port_clear_brport_flags > - Replaced "dsa_port_vlan_filtering(dp, br, extack)" with > "dsa_port_vlan_filtering(dp, br_vlan_enabled(br), extack)" (duh) > - Added review tags (sorry if I missed any) > > [...] Here is the summary with links: - [v4,net-next,01/11] net: bridge: add helper for retrieving the current bridge port STP state https://git.kernel.org/netdev/net-next/c/c0e715bbd50e - [v4,net-next,02/11] net: bridge: add helper to retrieve the current ageing time https://git.kernel.org/netdev/net-next/c/f1d42ea10056 - [v4,net-next,03/11] net: bridge: add helper to replay port and host-joined mdb entries https://git.kernel.org/netdev/net-next/c/4f2673b3a2b6 - [v4,net-next,04/11] net: bridge: add helper to replay port and local fdb entries https://git.kernel.org/netdev/net-next/c/04846f903b53 - [v4,net-next,05/11] net: bridge: add helper to replay VLANs installed on port https://git.kernel.org/netdev/net-next/c/22f67cdfae6a - [v4,net-next,06/11] net: dsa: call dsa_port_bridge_join when joining a LAG that is already in a bridge https://git.kernel.org/netdev/net-next/c/185c9a760a61 - [v4,net-next,07/11] net: dsa: pass extack to dsa_port_{bridge,lag}_join https://git.kernel.org/netdev/net-next/c/2afc526ab342 - [v4,net-next,08/11] net: dsa: inherit the actual bridge port flags at join time https://git.kernel.org/netdev/net-next/c/5961d6a12c13 - [v4,net-next,09/11] net: dsa: sync up switchdev objects and port attributes when joining the bridge https://git.kernel.org/netdev/net-next/c/010e269f91be - [v4,net-next,10/11] net: ocelot: call ocelot_netdevice_bridge_join when joining a bridged LAG https://git.kernel.org/netdev/net-next/c/81ef35e7619a - [v4,net-next,11/11] net: ocelot: replay switchdev events when joining bridge https://git.kernel.org/netdev/net-next/c/e4bd44e89dcf You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
From: Vladimir Oltean <vladimir.oltean@nxp.com> Changes in v4: - Added missing EXPORT_SYMBOL_GPL - Using READ_ONCE(fdb->dst) - Split patches into (a) adding the bridge helpers (b) making DSA use them - br_mdb_replay went back to the v1 approach where it allocated memory in atomic context - Created a br_switchdev_mdb_populate which reduces some of the code duplication - Fixed the error message in dsa_port_clear_brport_flags - Replaced "dsa_port_vlan_filtering(dp, br, extack)" with "dsa_port_vlan_filtering(dp, br_vlan_enabled(br), extack)" (duh) - Added review tags (sorry if I missed any) The objective of this series is to make LAG uppers on top of switchdev ports work regardless of which order we link interfaces to their masters (first make the port join the LAG, then the LAG join the bridge, or the other way around). There was a design decision to be made in patches 2-4 on whether we should adopt the "push" model (which attempts to solve the problem centrally, in the bridge layer) where the driver just calls: switchdev_bridge_port_offloaded(brport_dev, &atomic_notifier_block, &blocking_notifier_block, extack); and the bridge just replays the entire collection of switchdev port attributes and objects that it has, in some predefined order and with some predefined error handling logic; or the "pull" model (which attempts to solve the problem by giving the driver the rope to hang itself), where the driver, apart from calling: switchdev_bridge_port_offloaded(brport_dev, extack); has the task of "dumpster diving" (as Tobias puts it) through the bridge attributes and objects by itself, by calling: - br_vlan_replay - br_fdb_replay - br_mdb_replay - br_vlan_enabled - br_port_flag_is_set - br_port_get_stp_state - br_multicast_router - br_get_ageing_time (not necessarily all of them, and not necessarily in this order, and with driver-defined error handling). Even though I'm not in love myself with the "pull" model, I chose it because there is a fundamental trick with replaying switchdev events like this: ip link add br0 type bridge ip link add bond0 type bond ip link set bond0 master br0 ip link set swp0 master bond0 <- this will replay the objects once for the bond0 bridge port, and the swp0 switchdev port will process them ip link set swp1 master bond0 <- this will replay the objects again for the bond0 bridge port, and the swp1 switchdev port will see them, but swp0 will see them for the second time now Basically I believe that it is implementation defined whether the driver wants to error out on switchdev objects seen twice on a port, and the bridge should not enforce a certain model for that. For example, for FDB entries added to a bonding interface, the underling switchdev driver might have an abstraction for just that: an FDB entry pointing towards a logical (as opposed to physical) port. So when the second port joins the bridge, it doesn't realy need to replay FDB entries, since there is already at least one hardware port which has been receiving those events, and the FDB entries don't need to be added a second time to the same logical port. In the other corner, we have the drivers that handle switchdev port attributes on a LAG as individual switchdev port attributes on physical ports (example: VLAN filtering). In fact, the switchdev_handle_port_attr_set helper facilitates this: it is a fan-out from a single orig_dev towards multiple lowers that pass the check_cb(). But that's the point: switchdev_handle_port_attr_set is just a helper which the driver _opts_ to use. The bridge can't enforce the "push" model, because that would assume that all drivers handle port attributes in the same way, which is probably false. For this reason, I preferred to go with the "pull" mode for this patch set. Just to see how bad it is for other switchdev drivers to copy-paste this logic, I added the pull support to ocelot too, and I think it's pretty manageable. Vladimir Oltean (11): net: bridge: add helper for retrieving the current bridge port STP state net: bridge: add helper to retrieve the current ageing time net: bridge: add helper to replay port and host-joined mdb entries net: bridge: add helper to replay port and local fdb entries net: bridge: add helper to replay VLANs installed on port net: dsa: call dsa_port_bridge_join when joining a LAG that is already in a bridge net: dsa: pass extack to dsa_port_{bridge,lag}_join net: dsa: inherit the actual bridge port flags at join time net: dsa: sync up switchdev objects and port attributes when joining the bridge net: ocelot: call ocelot_netdevice_bridge_join when joining a bridged LAG net: ocelot: replay switchdev events when joining bridge drivers/net/dsa/ocelot/felix.c | 4 +- drivers/net/ethernet/mscc/Kconfig | 3 +- drivers/net/ethernet/mscc/ocelot.c | 18 +-- drivers/net/ethernet/mscc/ocelot_net.c | 208 +++++++++++++++++++++---- include/linux/if_bridge.h | 40 +++++ include/net/switchdev.h | 1 + include/soc/mscc/ocelot.h | 6 +- net/bridge/br_fdb.c | 50 ++++++ net/bridge/br_mdb.c | 148 ++++++++++++++++-- net/bridge/br_stp.c | 27 ++++ net/bridge/br_vlan.c | 73 +++++++++ net/dsa/dsa_priv.h | 9 +- net/dsa/port.c | 197 +++++++++++++++++------ net/dsa/slave.c | 11 +- 14 files changed, 675 insertions(+), 120 deletions(-)