[net-next 01/10] mlx5: count all link events
From: Saeed Mahameed <saeed@kernel.org>
Date: 2021-06-03 20:12:02
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
From: Jakub Kicinski <kuba@kernel.org> 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> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com> --- .../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 ad0f69480b9c..e36d0c6a08db 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 fc8b56bcabf3..e9c0afc8becc 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c@@ -540,6 +540,24 @@ 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