| Message ID | 20211024171757.3753288-1-vladimir.oltean@nxp.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Drop rtnl_lock from DSA .port_fdb_{add,del} | expand |
Hello: This series was applied to netdev/net-next.git (master) by David S. Miller <davem@davemloft.net>: On Sun, 24 Oct 2021 20:17:47 +0300 you wrote: > As mentioned in the RFC posted 2 months ago: > https://patchwork.kernel.org/project/netdevbpf/cover/20210824114049.3814660-1-vladimir.oltean@nxp.com/ > > DSA is transitioning to a driver API where the rtnl_lock is not held > when calling ds->ops->port_fdb_add() and ds->ops->port_fdb_del(). > Drivers cannot take that lock privately from those callbacks either. > > [...] Here is the summary with links: - [v5,net-next,01/10] net: dsa: avoid refcount warnings when ->port_{fdb,mdb}_del returns error https://git.kernel.org/netdev/net-next/c/232deb3f9567 - [v5,net-next,02/10] net: dsa: sja1105: wait for dynamic config command completion on writes too https://git.kernel.org/netdev/net-next/c/df405910ab9f - [v5,net-next,03/10] net: dsa: sja1105: serialize access to the dynamic config interface https://git.kernel.org/netdev/net-next/c/eb016afd83a9 - [v5,net-next,04/10] net: mscc: ocelot: serialize access to the MAC table https://git.kernel.org/netdev/net-next/c/2468346c5677 - [v5,net-next,05/10] net: dsa: b53: serialize access to the ARL table https://git.kernel.org/netdev/net-next/c/f7eb4a1c0864 - [v5,net-next,06/10] net: dsa: lantiq_gswip: serialize access to the PCE registers https://git.kernel.org/netdev/net-next/c/cf231b436f7c - [v5,net-next,07/10] net: dsa: introduce locking for the address lists on CPU and DSA ports https://git.kernel.org/netdev/net-next/c/338a3a4745aa - [v5,net-next,08/10] net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work https://git.kernel.org/netdev/net-next/c/5cdfde49a07f - [v5,net-next,09/10] selftests: lib: forwarding: allow tests to not require mz and jq https://git.kernel.org/netdev/net-next/c/d70b51f2845d - [v5,net-next,10/10] selftests: net: dsa: add a stress test for unlocked FDB operations https://git.kernel.org/netdev/net-next/c/edc90d15850c You are awesome, thank you!
As mentioned in the RFC posted 2 months ago: https://patchwork.kernel.org/project/netdevbpf/cover/20210824114049.3814660-1-vladimir.oltean@nxp.com/ DSA is transitioning to a driver API where the rtnl_lock is not held when calling ds->ops->port_fdb_add() and ds->ops->port_fdb_del(). Drivers cannot take that lock privately from those callbacks either. This change is required so that DSA can wait for switchdev FDB work items to finish before leaving the bridge. That change will be made in a future patch series. A small selftest is provided with the patch set in the hope that concurrency issues uncovered by this series, but not spotted by me by code inspection, will be caught. A status of the existing drivers: - mv88e6xxx_port_fdb_add() and mv88e6xxx_port_fdb_del() take mv88e6xxx_reg_lock() so they should be safe. - qca8k_fdb_add() and qca8k_fdb_del() take mutex_lock(&priv->reg_mutex) so they should be safe. - hellcreek_fdb_add() and hellcreek_fdb_add() take mutex_lock(&hellcreek->reg_lock) so they should be safe. - ksz9477_port_fdb_add() and ksz9477_port_fdb_del() take mutex_lock(&dev->alu_mutex) so they should be safe. - b53_fdb_add() and b53_fdb_del() did not have locking, so I've added a scheme based on my own judgement there (not tested). - felix_fdb_add() and felix_fdb_del() did not have locking, I've added and tested a locking scheme there. - mt7530_port_fdb_add() and mt7530_port_fdb_del() take mutex_lock(&priv->reg_mutex), so they should be safe. - gswip_port_fdb() did not have locking, so I've added a non-expert locking scheme based on my own judgement (not tested). - lan9303_alr_add_port() and lan9303_alr_del_port() take mutex_lock(&chip->alr_mutex) so they should be safe. - sja1105_fdb_add() and sja1105_fdb_del() did not have locking, I've added and tested a locking scheme. Changes in v3: Unlock arl_mutex only once in b53_fdb_dump(). Changes in v4: - Use __must_hold in ocelot and b53 - Add missing mutex_init in lantiq_gswip - Clean up the selftest a bit. Changes in v5: - Replace __must_hold with a comment. - Add a new patch (01/10). Vladimir Oltean (10): net: dsa: avoid refcount warnings when ->port_{fdb,mdb}_del returns error net: dsa: sja1105: wait for dynamic config command completion on writes too net: dsa: sja1105: serialize access to the dynamic config interface net: mscc: ocelot: serialize access to the MAC table net: dsa: b53: serialize access to the ARL table net: dsa: lantiq_gswip: serialize access to the PCE registers net: dsa: introduce locking for the address lists on CPU and DSA ports net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work selftests: lib: forwarding: allow tests to not require mz and jq selftests: net: dsa: add a stress test for unlocked FDB operations MAINTAINERS | 1 + drivers/net/dsa/b53/b53_common.c | 36 ++++++-- drivers/net/dsa/b53/b53_priv.h | 1 + drivers/net/dsa/lantiq_gswip.c | 28 +++++- drivers/net/dsa/sja1105/sja1105.h | 2 + .../net/dsa/sja1105/sja1105_dynamic_config.c | 91 ++++++++++++++----- drivers/net/dsa/sja1105/sja1105_main.c | 1 + drivers/net/ethernet/mscc/ocelot.c | 53 ++++++++--- include/net/dsa.h | 1 + include/soc/mscc/ocelot.h | 3 + net/dsa/dsa2.c | 1 + net/dsa/slave.c | 2 - net/dsa/switch.c | 80 ++++++++++------ .../drivers/net/dsa/test_bridge_fdb_stress.sh | 47 ++++++++++ tools/testing/selftests/net/forwarding/lib.sh | 10 +- 15 files changed, 280 insertions(+), 77 deletions(-) create mode 100755 tools/testing/selftests/drivers/net/dsa/test_bridge_fdb_stress.sh