net/mlx5e: Disable Striding RQ when PCI is slower than link
authorTariq Toukan <tariqt@mellanox.com>
Sun, 11 Feb 2018 09:58:30 +0000 (11:58 +0200)
committerSaeed Mahameed <saeedm@mellanox.com>
Wed, 28 Mar 2018 00:17:27 +0000 (17:17 -0700)
We turn the feature off for servers with PCI BW bounded
by a threshold (16G) and lower than MAX LINK BW.
This improves the effectiveness of CQE compression feature,
that is defaulted to ON for the same case.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
drivers/net/ethernet/mellanox/mlx5/core/en_main.c

index 46707826f27e1ff860fbee8e1a7e337986cf01fb..d4dd00089eb11f755bd0c03ab37c0da1add2a903 100644 (file)
@@ -113,13 +113,16 @@ void mlx5e_init_rq_type_params(struct mlx5_core_dev *mdev,
                       MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_CQE_COMPRESS));
 }
 
+static bool slow_pci_heuristic(struct mlx5_core_dev *mdev);
+
 static void mlx5e_set_rq_params(struct mlx5_core_dev *mdev,
                                struct mlx5e_params *params)
 {
        u8 rq_type = mlx5e_check_fragmented_striding_rq_cap(mdev) &&
-                   !params->xdp_prog && !MLX5_IPSEC_DEV(mdev) ?
-                   MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ :
-                   MLX5_WQ_TYPE_LINKED_LIST;
+               !slow_pci_heuristic(mdev) &&
+               !params->xdp_prog && !MLX5_IPSEC_DEV(mdev) ?
+               MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ :
+               MLX5_WQ_TYPE_LINKED_LIST;
        mlx5e_init_rq_type_params(mdev, params, rq_type);
 }