[PATCH net-next] mlx5: count all link events
From: Jakub Kicinski <kuba@kernel.org>
Date: 2021-05-19 17:18:37
Subsystem:
mellanox ethernet driver (mlx5e), mellanox mlx5 core vpi driver, networking drivers, networking [general], tc subsystem, the rest · Maintainers:
Saeed Mahameed, Tariq Toukan, Mark Bloch, Leon Romanovsky, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
mlx5 devices were observed generating MLX5_PORT_CHANGE_SUBTYPE_ACTIVE events without an intervening MLX5_PORT_CHANGE_SUBTYPE_DOWN. This breaks link flap detection based on Linux carrier state transition count as netif_carrier_on() does nothing if carrier is already on. Make sure we count such events. netif_carrier_event() increments the counters and fires the linkwatch events. The latter is not necessary for the use case but seems like the right thing to do. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- .../net/ethernet/mellanox/mlx5/core/en_main.c | 6 +++++- include/linux/netdevice.h | 2 +- net/sched/sch_generic.c | 18 ++++++++++++++++++ 3 files changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index bca832cdc4cb..5a67ebc0c96c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c@@ -91,12 +91,16 @@ void mlx5e_update_carrier(struct mlx5e_priv *priv) { struct mlx5_core_dev *mdev = priv->mdev; u8 port_state; + bool up; port_state = mlx5_query_vport_state(mdev, MLX5_VPORT_STATE_OP_MOD_VNIC_VPORT, 0); - if (port_state == VPORT_STATE_UP) { + up = port_state == VPORT_STATE_UP; + if (up == netif_carrier_ok(priv->netdev)) + netif_carrier_event(priv->netdev); + if (up) { netdev_info(priv->netdev, "Link up\n"); netif_carrier_on(priv->netdev); } else {
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 5cbc950b34df..be1dcceda5e4 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h@@ -4187,8 +4187,8 @@ unsigned long dev_trans_start(struct net_device *dev); void __netdev_watchdog_up(struct net_device *dev); void netif_carrier_on(struct net_device *dev); - void netif_carrier_off(struct net_device *dev); +void netif_carrier_event(struct net_device *dev); /** * netif_dormant_on - mark device as dormant.
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 44991ea726fc..3090ae32307b 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c@@ -515,6 +515,24 @@ void netif_carrier_off(struct net_device *dev) } EXPORT_SYMBOL(netif_carrier_off); +/** + * netif_carrier_event - report carrier state event + * @dev: network device + * + * Device has detected a carrier event but the carrier state wasn't changed. + * Use in drivers when querying carrier state asynchronously, to avoid missing + * events (link flaps) if link recovers before it's queried. + */ +void netif_carrier_event(struct net_device *dev) +{ + if (dev->reg_state == NETREG_UNINITIALIZED) + return; + atomic_inc(&dev->carrier_up_count); + atomic_inc(&dev->carrier_down_count); + linkwatch_fire_event(dev); +} +EXPORT_SYMBOL_GPL(netif_carrier_event); + /* "NOOP" scheduler: the best scheduler, recommended for all interfaces under all circumstances. It is difficult to invent anything faster or cheaper.
--
2.31.1