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[net-next,11/14] mlxsw: spectrum_router: Avoid unnecessary neighbour updates

Message ID 20210322155855.3164151-12-idosch@idosch.org (mailing list archive)
State Accepted
Commit c1efd50002c00cbe51014ddf357d55162cd7d6d8
Delegated to: Netdev Maintainers
Headers show
Series mlxsw: Preparations for resilient nexthop groups | expand

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Commit Message

Ido Schimmel March 22, 2021, 3:58 p.m. UTC
From: Ido Schimmel <idosch@nvidia.com>

Avoid updating neighbour and adjacency entries in hardware when the
neighbour is already connected and its MAC address did not change. This
can happen, for example, when neighbour transitions between valid states
such as 'NUD_REACHABLE' and 'NUD_DELAY'.

This is especially important for resilient hashing as these updates will
result in adjacency entries being marked as active.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index fa190e27323e..4114f3b7d3cd 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -2662,6 +2662,10 @@  static void mlxsw_sp_router_neigh_event_work(struct work_struct *work)
 			goto out;
 	}
 
+	if (neigh_entry->connected && entry_connected &&
+	    !memcmp(neigh_entry->ha, ha, ETH_ALEN))
+		goto out;
+
 	memcpy(neigh_entry->ha, ha, ETH_ALEN);
 	mlxsw_sp_neigh_entry_update(mlxsw_sp, neigh_entry, entry_connected);
 	mlxsw_sp_nexthop_neigh_update(mlxsw_sp, neigh_entry, !entry_connected,