Subject: [net 4/5] net/mlx5e: Lag, Only handle events from highest priority multipath entry

From: Saeed Mahameed <[email-masked]>
Date: Wed, 9 Mar 2022 12:15:16 -0800

From: Roi Dayan <[email-masked]>

There could be multiple multipath entries but changing the port affinity
for each one doesn't make much sense and there should be a default one.
So only track the entry with lowest priority value.
The commit doesn't affect existing users with a single entry.

Fixes: 544fe7c2e654 ("net/mlx5e: Activate HW multipath and handle port affinity based on FIB events")
Signed-off-by: Roi Dayan <[email-masked]>
Reviewed-by: Maor Dickman <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/lag/mp.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag/mp.c b/drivers/net/ethernet/mellanox/mlx5/core/lag/mp.c
index 1ca01a5b6cdd..626aa60b6099 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag/mp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag/mp.c
@@ -126,6 +126,10 @@ static void mlx5_lag_fib_route_event(struct mlx5_lag *ldev,
 		return;
 	}
 
+	/* Handle multipath entry with lower priority value */
+	if (mp->mfi && mp->mfi != fi && fi->fib_priority >= mp->mfi->fib_priority)
+		return;
+
 	/* Handle add/replace event */
 	nhs = fib_info_num_path(fi);
 	if (nhs == 1) {
@@ -135,12 +139,13 @@ static void mlx5_lag_fib_route_event(struct mlx5_lag *ldev,
 			int i = mlx5_lag_dev_get_netdev_idx(ldev, nh_dev);
 
 			if (i < 0)
-				i = MLX5_LAG_NORMAL_AFFINITY;
-			else
-				++i;
+				return;
 
+			i++;
 			mlx5_lag_set_port_affinity(ldev, i);
 		}
+
+		mp->mfi = fi;
 		return;
 	}
 
-- 
2.35.1