net/mlx4_en: Optimized single ring steering

Avoid touching RX QP RSS context when loading with only
one RX ring, to allow optimized A0 RX steering.

Enable by:
- loading mlx4_core with module param: log_num_mgm_entry_size = -6.
- then: ethtool -L <interface> rx 1

Performance tests:
Tested on ConnectX3Pro, Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz

XDP_DROP packet rate:
-------------------------------------
     | Before    | After     | Gain |
IPv4 | 20.5 Mpps | 28.1 Mpps |  37% |
IPv6 | 18.4 Mpps | 28.1 Mpps |  53% |
-------------------------------------

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Cc: kernel-team@fb.com
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_main.c b/drivers/net/ethernet/mellanox/mlx4/en_main.c
index d94f981eafc4075f44e92fe7e91122976030ae40..56cdf38d150e714d4b260a15e6921c5940216da8 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_main.c
@@ -125,9 +125,9 @@ void mlx4_en_update_loopback_state(struct net_device *dev,
                priv->flags |= MLX4_EN_FLAG_ENABLE_HW_LOOPBACK;
 
        mutex_lock(&priv->mdev->state_lock);
-       if (priv->mdev->dev->caps.flags2 &
-           MLX4_DEV_CAP_FLAG2_UPDATE_QP_SRC_CHECK_LB &&
-           priv->rss_map.indir_qp.qpn) {
+       if ((priv->mdev->dev->caps.flags2 &
+            MLX4_DEV_CAP_FLAG2_UPDATE_QP_SRC_CHECK_LB) &&
+           priv->rss_map.indir_qp && priv->rss_map.indir_qp->qpn) {
                int i;
                int err = 0;
                int loopback = !!(features & NETIF_F_LOOPBACK);

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index c1de75fc399a31fc30d34b4a8ffe84a05baa7a85..51ce111b719e9b8fdaced81948c5fd62c8a93a13 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -596,6 +596,8 @@ static int mlx4_en_get_qp(struct mlx4_en_priv *priv)
                return err;
        }
 
+       en_info(priv, "Steering Mode %d\n", dev->caps.steering_mode);
+
        if (dev->caps.steering_mode == MLX4_STEERING_MODE_A0) {
                int base_qpn = mlx4_get_base_qpn(dev, priv->port);
                *qpn = base_qpn + index;
@@ -1010,7 +1012,7 @@ static void mlx4_en_do_multicast(struct mlx4_en_priv *priv,
                                memcpy(&mc_list[10], mclist->addr, ETH_ALEN);
                                mc_list[5] = priv->port;
                                err = mlx4_multicast_detach(mdev->dev,
-                                                           &priv->rss_map.indir_qp,
+                                                           priv->rss_map.indir_qp,
                                                            mc_list,
                                                            MLX4_PROT_ETH,
                                                            mclist->reg_id);
@@ -1032,7 +1034,7 @@ static void mlx4_en_do_multicast(struct mlx4_en_priv *priv,
                                /* needed for B0 steering support */
                                mc_list[5] = priv->port;
                                err = mlx4_multicast_attach(mdev->dev,
-                                                           &priv->rss_map.indir_qp,
+                                                           priv->rss_map.indir_qp,
                                                            mc_list,
                                                            priv->port, 0,
                                                            MLX4_PROT_ETH,
@@ -1742,7 +1744,7 @@ int mlx4_en_start_port(struct net_device *dev)
        /* Attach rx QP to bradcast address */
        eth_broadcast_addr(&mc_list[10]);
        mc_list[5] = priv->port; /* needed for B0 steering support */
-       if (mlx4_multicast_attach(mdev->dev, &priv->rss_map.indir_qp, mc_list,
+       if (mlx4_multicast_attach(mdev->dev, priv->rss_map.indir_qp, mc_list,
                                  priv->port, 0, MLX4_PROT_ETH,
                                  &priv->broadcast_id))
                mlx4_warn(mdev, "Failed Attaching Broadcast\n");
@@ -1866,12 +1868,12 @@ void mlx4_en_stop_port(struct net_device *dev, int detach)
        /* Detach All multicasts */
        eth_broadcast_addr(&mc_list[10]);
        mc_list[5] = priv->port; /* needed for B0 steering support */
-       mlx4_multicast_detach(mdev->dev, &priv->rss_map.indir_qp, mc_list,
+       mlx4_multicast_detach(mdev->dev, priv->rss_map.indir_qp, mc_list,
                              MLX4_PROT_ETH, priv->broadcast_id);
        list_for_each_entry(mclist, &priv->curr_list, list) {
                memcpy(&mc_list[10], mclist->addr, ETH_ALEN);
                mc_list[5] = priv->port;
-               mlx4_multicast_detach(mdev->dev, &priv->rss_map.indir_qp,
+               mlx4_multicast_detach(mdev->dev, priv->rss_map.indir_qp,
                                      mc_list, MLX4_PROT_ETH, mclist->reg_id);
                if (mclist->tunnel_reg_id)
                        mlx4_flow_detach(mdev->dev, mclist->tunnel_reg_id);

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 77abd181304750c0e67b67526c129000d63a8e35..c4edae854f1b59855b816235472e277ddb639547 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -1099,11 +1099,14 @@ int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
        int i, qpn;
        int err = 0;
        int good_qps = 0;
+       u8 flags;
 
        en_dbg(DRV, priv, "Configuring rss steering\n");
+
+       flags = priv->rx_ring_num == 1 ? MLX4_RESERVE_A0_QP : 0;
        err = mlx4_qp_reserve_range(mdev->dev, priv->rx_ring_num,
                                    priv->rx_ring_num,
-                                   &rss_map->base_qpn, 0);
+                                   &rss_map->base_qpn, flags);
        if (err) {
                en_err(priv, "Failed reserving %d qps\n", priv->rx_ring_num);
                return err;
@@ -1120,13 +1123,28 @@ int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
                ++good_qps;
        }
 
+       if (priv->rx_ring_num == 1) {
+               rss_map->indir_qp = &rss_map->qps[0];
+               priv->base_qpn = rss_map->indir_qp->qpn;
+               en_info(priv, "Optimized Non-RSS steering\n");
+               return 0;
+       }
+
+       rss_map->indir_qp = kzalloc(sizeof(*rss_map->indir_qp), GFP_KERNEL);
+       if (!rss_map->indir_qp) {
+               err = -ENOMEM;
+               goto rss_err;
+       }
+
        /* Configure RSS indirection qp */
-       err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, &rss_map->indir_qp, GFP_KERNEL);
+       err = mlx4_qp_alloc(mdev->dev, priv->base_qpn, rss_map->indir_qp,
+                           GFP_KERNEL);
        if (err) {
                en_err(priv, "Failed to allocate RSS indirection QP\n");
                goto rss_err;
        }
-       rss_map->indir_qp.event = mlx4_en_sqp_event;
+
+       rss_map->indir_qp->event = mlx4_en_sqp_event;
        mlx4_en_fill_qp_context(priv, 0, 0, 0, 1, priv->base_qpn,
                                priv->rx_ring[0]->cqn, -1, &context);
 
@@ -1164,8 +1182,9 @@ int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
                err = -EINVAL;
                goto indir_err;
        }
+
        err = mlx4_qp_to_ready(mdev->dev, &priv->res.mtt, &context,
-                              &rss_map->indir_qp, &rss_map->indir_state);
+                              rss_map->indir_qp, &rss_map->indir_state);
        if (err)
                goto indir_err;
 
@@ -1173,9 +1192,11 @@ int mlx4_en_config_rss_steer(struct mlx4_en_priv *priv)
 
 indir_err:
        mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
-                      MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
-       mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
-       mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
+                      MLX4_QP_STATE_RST, NULL, 0, 0, rss_map->indir_qp);
+       mlx4_qp_remove(mdev->dev, rss_map->indir_qp);
+       mlx4_qp_free(mdev->dev, rss_map->indir_qp);
+       kfree(rss_map->indir_qp);
+       rss_map->indir_qp = NULL;
 rss_err:
        for (i = 0; i < good_qps; i++) {
                mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],
@@ -1193,10 +1214,15 @@ void mlx4_en_release_rss_steer(struct mlx4_en_priv *priv)
        struct mlx4_en_rss_map *rss_map = &priv->rss_map;
        int i;
 
-       mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
-                      MLX4_QP_STATE_RST, NULL, 0, 0, &rss_map->indir_qp);
-       mlx4_qp_remove(mdev->dev, &rss_map->indir_qp);
-       mlx4_qp_free(mdev->dev, &rss_map->indir_qp);
+       if (priv->rx_ring_num > 1) {
+               mlx4_qp_modify(mdev->dev, NULL, rss_map->indir_state,
+                              MLX4_QP_STATE_RST, NULL, 0, 0,
+                              rss_map->indir_qp);
+               mlx4_qp_remove(mdev->dev, rss_map->indir_qp);
+               mlx4_qp_free(mdev->dev, rss_map->indir_qp);
+               kfree(rss_map->indir_qp);
+               rss_map->indir_qp = NULL;
+       }
 
        for (i = 0; i < priv->rx_ring_num; i++) {
                mlx4_qp_modify(mdev->dev, NULL, rss_map->state[i],

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index ccae3c6593c463f7e79394200be7199481e60c0b..457e070bca46ea41587a3d28f2363e52debaab0c 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -2356,8 +2356,8 @@ static int mlx4_init_hca(struct mlx4_dev *dev)
                                        MLX4_A0_STEERING_TABLE_SIZE;
                        }
 
-                       mlx4_dbg(dev, "DMFS high rate steer mode is: %s\n",
-                                dmfs_high_rate_steering_mode_str(
+                       mlx4_info(dev, "DMFS high rate steer mode is: %s\n",
+                                 dmfs_high_rate_steering_mode_str(
                                        dev->caps.dmfs_high_steer_mode));
                }
        } else {

diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 08b2906a98af88194277d63a21c6fb389f99e88e..41f4f8f9f300e9ea207be5d6010b2d5e9f767ca1 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -431,7 +431,7 @@ struct mlx4_en_rss_map {
        int base_qpn;
        struct mlx4_qp qps[MAX_RX_RINGS];
        enum mlx4_qp_state state[MAX_RX_RINGS];
-       struct mlx4_qp indir_qp;
+       struct mlx4_qp *indir_qp;
        enum mlx4_qp_state indir_state;
 };