[PATCH net-next V2 0/2] net/mlx5e: Disable egress xdp-redirect in default

[PATCH net-next V2 0/2] net/mlx5e: Disable egress xdp-redirect in default

[Tariq Toukan]

Hi,

This small series disables the egress xdp-redirect feature in default.
It can still be enabled by loading a dummy XDP program.

Patches were previously submitted as part of [1].

This reduces the default number of SQs in each channel from 4 to 3, and
saves resources in device and host memory.

This also improves the latency of channel configuration operations, like
interface up (create channels), interface down (destroy channels), and
channels reconfiguration (create new set, destroy old one).

Perf numbers:
NIC: Connect-X7.
Setup: 248 channels, default mtu and rx/tx ring sizes.

Interface up + down:
Before: 2.246 secs
After:  1.798 secs (-0.448 sec)

Saves ~1.8 msec per channel.

Regards,
Tariq

[1]
https://lore.kernel.org/all/1762939749-1165658-1-git-send-email-tariqt@nvidia.com/

V2:
- Enhanced commit message.

Tariq Toukan (2):
  net/mlx5e: Update XDP features in switch channels
  net/mlx5e: Support XDP target xmit with dummy program

 drivers/net/ethernet/mellanox/mlx5/core/en.h  |  2 +-
 .../ethernet/mellanox/mlx5/core/en_ethtool.c  | 10 +-----
 .../net/ethernet/mellanox/mlx5/core/en_main.c | 36 +++++++++----------
 .../net/ethernet/mellanox/mlx5/core/en_rep.c  |  2 +-
 4 files changed, 20 insertions(+), 30 deletions(-)


base-commit: 0177f0f07886e54e12c6f18fa58f63e63ddd3c58
-- 
2.31.1

[PATCH net-next V2 1/2] net/mlx5e: Update XDP features in switch channels

[Tariq Toukan]

The XDP features state might depend of the state of other features, like
HW-LRO / HW-GRO.

In general, move the re-evaluation announcement of the XDP features
(xdp_set_features_flag_locked) into the flow where configuration gets
changed. There's no point in updating them elsewhere.

This is a more appropriate place, as this modifies the announced
features while channels are inactive, which avoids the small interval
between channel activation and the proper setting of the XDP features.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: William Tu <witu@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en.h        |  2 +-
 .../net/ethernet/mellanox/mlx5/core/en_ethtool.c    | 10 +---------
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c   | 13 ++++++-------
 drivers/net/ethernet/mellanox/mlx5/core/en_rep.c    |  2 +-
 4 files changed, 9 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 3ada7c16adfb..811178d8976c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -1249,7 +1249,7 @@ void mlx5e_netdev_attach_nic_profile(struct mlx5e_priv *priv);
 void mlx5e_set_netdev_mtu_boundaries(struct mlx5e_priv *priv);
 void mlx5e_build_nic_params(struct mlx5e_priv *priv, struct mlx5e_xsk *xsk, u16 mtu);
 
-void mlx5e_set_xdp_feature(struct net_device *netdev);
+void mlx5e_set_xdp_feature(struct mlx5e_priv *priv);
 netdev_features_t mlx5e_features_check(struct sk_buff *skb,
 				       struct net_device *netdev,
 				       netdev_features_t features);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index fe67c73849f9..d3fef1e7e2f7 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -2294,7 +2294,6 @@ static int set_pflag_rx_striding_rq(struct net_device *netdev, bool enable)
 	struct mlx5e_priv *priv = netdev_priv(netdev);
 	struct mlx5_core_dev *mdev = priv->mdev;
 	struct mlx5e_params new_params;
-	int err;
 
 	if (enable) {
 		/* Checking the regular RQ here; mlx5e_validate_xsk_param called
@@ -2315,14 +2314,7 @@ static int set_pflag_rx_striding_rq(struct net_device *netdev, bool enable)
 	MLX5E_SET_PFLAG(&new_params, MLX5E_PFLAG_RX_STRIDING_RQ, enable);
 	mlx5e_set_rq_type(mdev, &new_params);
 
-	err = mlx5e_safe_switch_params(priv, &new_params, NULL, NULL, true);
-	if (err)
-		return err;
-
-	/* update XDP supported features */
-	mlx5e_set_xdp_feature(netdev);
-
-	return 0;
+	return mlx5e_safe_switch_params(priv, &new_params, NULL, NULL, true);
 }
 
 static int set_pflag_rx_no_csum_complete(struct net_device *netdev, bool enable)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index e537df670758..f0f2bc7f317d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3365,6 +3365,7 @@ static int mlx5e_switch_priv_params(struct mlx5e_priv *priv,
 		}
 	}
 
+	mlx5e_set_xdp_feature(priv);
 	return 0;
 }
 
@@ -3396,6 +3397,7 @@ static int mlx5e_switch_priv_channels(struct mlx5e_priv *priv,
 		}
 	}
 
+	mlx5e_set_xdp_feature(priv);
 	if (!MLX5_CAP_GEN(priv->mdev, tis_tir_td_order))
 		mlx5e_close_channels(old_chs);
 	priv->profile->update_rx(priv);
@@ -4409,10 +4411,10 @@ static int mlx5e_handle_feature(struct net_device *netdev,
 	return 0;
 }
 
-void mlx5e_set_xdp_feature(struct net_device *netdev)
+void mlx5e_set_xdp_feature(struct mlx5e_priv *priv)
 {
-	struct mlx5e_priv *priv = netdev_priv(netdev);
 	struct mlx5e_params *params = &priv->channels.params;
+	struct net_device *netdev = priv->netdev;
 	xdp_features_t val;
 
 	if (!netdev->netdev_ops->ndo_bpf ||
@@ -4461,9 +4463,6 @@ int mlx5e_set_features(struct net_device *netdev, netdev_features_t features)
 		return -EINVAL;
 	}
 
-	/* update XDP supported features */
-	mlx5e_set_xdp_feature(netdev);
-
 	return 0;
 }
 
@@ -5859,7 +5858,7 @@ static void mlx5e_build_nic_netdev(struct net_device *netdev)
 	netdev->netmem_tx = true;
 
 	netif_set_tso_max_size(netdev, GSO_MAX_SIZE);
-	mlx5e_set_xdp_feature(netdev);
+	mlx5e_set_xdp_feature(priv);
 	mlx5e_set_netdev_dev_addr(netdev);
 	mlx5e_macsec_build_netdev(priv);
 	mlx5e_ipsec_build_netdev(priv);
@@ -5957,7 +5956,7 @@ static int mlx5e_nic_init(struct mlx5_core_dev *mdev,
 
 	mlx5e_psp_register(priv);
 	/* update XDP supported features */
-	mlx5e_set_xdp_feature(netdev);
+	mlx5e_set_xdp_feature(priv);
 
 	if (take_rtnl)
 		rtnl_unlock();
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
index 0335ca8277ef..ee9595109649 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
@@ -867,7 +867,7 @@ static void mlx5e_build_rep_params(struct net_device *netdev)
 	if (take_rtnl)
 		rtnl_lock();
 	/* update XDP supported features */
-	mlx5e_set_xdp_feature(netdev);
+	mlx5e_set_xdp_feature(priv);
 	if (take_rtnl)
 		rtnl_unlock();
 
-- 
2.31.1

[PATCH net-next V2 2/2] net/mlx5e: Support XDP target xmit with dummy program

[Tariq Toukan]

Save per-channel resources in default, in device and host memory.

As no better API exist, make the XDP-redirect-target SQ available by
loading a dummy XDP program.

This improves the latency of interface up/down operations when feature
is disabled.

Perf numbers:
NIC: Connect-X7.
Setup: 248 channels, default mtu and rx/tx ring sizes.

Interface up + down:
Before: 2.246 secs
After:  1.798 secs (-0.448 sec)

Saves ~1.8 msec per channel.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: William Tu <witu@nvidia.com>
---
 .../net/ethernet/mellanox/mlx5/core/en_main.c | 23 +++++++++----------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index f0f2bc7f317d..6168f0814414 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -2612,7 +2612,7 @@ static int mlx5e_open_queues(struct mlx5e_channel *c,
 	if (err)
 		goto err_close_icosq_cq;
 
-	if (netdev_ops->ndo_xdp_xmit) {
+	if (netdev_ops->ndo_xdp_xmit && c->xdp) {
 		c->xdpsq = mlx5e_open_xdpredirect_sq(c, params, cparam, &ccp);
 		if (IS_ERR(c->xdpsq)) {
 			err = PTR_ERR(c->xdpsq);
@@ -4415,19 +4415,18 @@ void mlx5e_set_xdp_feature(struct mlx5e_priv *priv)
 {
 	struct mlx5e_params *params = &priv->channels.params;
 	struct net_device *netdev = priv->netdev;
-	xdp_features_t val;
+	xdp_features_t val = 0;
 
-	if (!netdev->netdev_ops->ndo_bpf ||
-	    params->packet_merge.type != MLX5E_PACKET_MERGE_NONE) {
-		xdp_set_features_flag_locked(netdev, 0);
-		return;
-	}
+	if (netdev->netdev_ops->ndo_bpf &&
+	    params->packet_merge.type == MLX5E_PACKET_MERGE_NONE)
+		val = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
+		      NETDEV_XDP_ACT_XSK_ZEROCOPY |
+		      NETDEV_XDP_ACT_RX_SG;
+
+	if (netdev->netdev_ops->ndo_xdp_xmit && params->xdp_prog)
+		val |= NETDEV_XDP_ACT_NDO_XMIT |
+			NETDEV_XDP_ACT_NDO_XMIT_SG;
 
-	val = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
-	      NETDEV_XDP_ACT_XSK_ZEROCOPY |
-	      NETDEV_XDP_ACT_RX_SG |
-	      NETDEV_XDP_ACT_NDO_XMIT |
-	      NETDEV_XDP_ACT_NDO_XMIT_SG;
 	xdp_set_features_flag_locked(netdev, val);
 }
 
-- 
2.31.1

Re: [PATCH net-next V2 0/2] net/mlx5e: Disable egress xdp-redirect in default

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Sun, 30 Nov 2025 12:13:35 +0200 you wrote:
> Hi,
> 
> This small series disables the egress xdp-redirect feature in default.
> It can still be enabled by loading a dummy XDP program.
> 
> Patches were previously submitted as part of [1].
> 
> [...]

Here is the summary with links:
  - [net-next,V2,1/2] net/mlx5e: Update XDP features in switch channels
    https://git.kernel.org/netdev/net-next/c/96a839506135
  - [net-next,V2,2/2] net/mlx5e: Support XDP target xmit with dummy program
    https://git.kernel.org/netdev/net-next/c/d4aa0cc9bd31

You are awesome, thank you!
-- 
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