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Message-ID: <Y8hW8IqJTa0zE2aS@google.com>
Date:   Wed, 18 Jan 2023 12:30:40 -0800
From:   sdf@...gle.com
To:     Lorenzo Bianconi <lorenzo@...nel.org>
Cc:     bpf@...r.kernel.org, netdev@...r.kernel.org, ast@...nel.org,
        daniel@...earbox.net, andrii@...nel.org, davem@...emloft.net,
        kuba@...nel.org, hawk@...nel.org, pabeni@...hat.com,
        edumazet@...gle.com, toke@...hat.com, memxor@...il.com,
        alardam@...il.com, saeedm@...dia.com, anthony.l.nguyen@...el.com,
        gospo@...adcom.com, vladimir.oltean@....com, nbd@....name,
        john@...ozen.org, leon@...nel.org, simon.horman@...igine.com,
        aelior@...vell.com, christophe.jaillet@...adoo.fr,
        ecree.xilinx@...il.com, mst@...hat.com, bjorn@...nel.org,
        magnus.karlsson@...el.com, maciej.fijalkowski@...el.com,
        intel-wired-lan@...ts.osuosl.org, lorenzo.bianconi@...hat.com
Subject: Re: [RFC v2 bpf-next 2/7] drivers: net: turn on XDP features

On 01/14, Lorenzo Bianconi wrote:
> From: Marek Majtyka <alardam@...il.com>

> A summary of the flags being set for various drivers is given below.
> Note that XDP_F_REDIRECT_TARGET and XDP_F_FRAG_TARGET are features
> that can be turned off and on at runtime. This means that these flags
> may be set and unset under RTNL lock protection by the driver. Hence,
> READ_ONCE must be used by code loading the flag value.

> Also, these flags are not used for synchronization against the  
> availability
> of XDP resources on a device. It is merely a hint, and hence the read
> may race with the actual teardown of XDP resources on the device. This
> may change in the future, e.g. operations taking a reference on the XDP
> resources of the driver, and in turn inhibiting turning off this flag.
> However, for now, it can only be used as a hint to check whether device
> supports becoming a redirection target.

> Turn 'hw-offload' feature flag on for:
>   - netronome (nfp)
>   - netdevsim.

> Turn 'native' and 'zerocopy' features flags on for:
>   - intel (i40e, ice, ixgbe, igc)
>   - mellanox (mlx5).
>   - stmmac

> Turn 'native' features flags on for:
>   - amazon (ena)
>   - broadcom (bnxt)
>   - freescale (dpaa, dpaa2, enetc)
>   - funeth
>   - intel (igb)
>   - marvell (mvneta, mvpp2, octeontx2)
>   - mellanox (mlx4)
>   - qlogic (qede)
>   - sfc
>   - socionext (netsec)
>   - ti (cpsw)
>   - tap
>   - veth
>   - xen
>   - virtio_net.

> Turn 'basic' (tx, pass, aborted and drop) features flags on for:
>   - netronome (nfp)
>   - cavium (thunder)
>   - hyperv.

> Turn 'tx_lock' feature flag on for:
>   - aquantia
>   - freescale (dpaa2)
>   - intel (igb)
>   - marvell (mvneta, mvpp2)
>   - microsoft (mana)
>   - mediatek
>   - qlogic (qede)
>   - socionext (netsec)
>   - ti (cpsw)
>   - tap
>   - veth
>   - xen

> Turn 'redirect_target' feature flag on for:
>   - amanzon (ena)
>   - broadcom (bnxt)
>   - freescale (dpaa, dpaa2)
>   - intel (i40e, ice, igb, ixgbe)
>   - ti (cpsw)
>   - marvell (mvneta, mvpp2)
>   - sfc
>   - socionext (netsec)
>   - qlogic (qede)
>   - mellanox (mlx5)
>   - tap
>   - veth
>   - virtio_net
>   - xen

> Co-developed-by: Kumar Kartikeya Dwivedi <memxor@...il.com>
> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@...il.com>
> Co-developed-by: Lorenzo Bianconi <lorenzo@...nel.org>
> Signed-off-by: Lorenzo Bianconi <lorenzo@...nel.org>
> Signed-off-by: Marek Majtyka <alardam@...il.com>
> ---
>   drivers/net/ethernet/amazon/ena/ena_netdev.c  |  5 +++
>   .../net/ethernet/aquantia/atlantic/aq_nic.c   |  4 ++
>   drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  2 +
>   drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |  2 +
>   .../net/ethernet/cavium/thunder/nicvf_main.c  |  2 +
>   .../net/ethernet/freescale/dpaa/dpaa_eth.c    |  2 +
>   .../net/ethernet/freescale/dpaa2/dpaa2-eth.c  |  2 +
>   .../net/ethernet/freescale/enetc/enetc_pf.c   |  2 +
>   .../ethernet/fungible/funeth/funeth_main.c    |  6 +++
>   drivers/net/ethernet/intel/i40e/i40e_main.c   |  9 ++++-
>   drivers/net/ethernet/intel/ice/ice_main.c     |  5 +++
>   drivers/net/ethernet/intel/igb/igb_main.c     |  9 ++++-
>   drivers/net/ethernet/intel/igc/igc_main.c     |  2 +
>   drivers/net/ethernet/intel/igc/igc_xdp.c      |  5 +++
>   drivers/net/ethernet/intel/ixgbe/ixgbe_main.c |  5 +++
>   .../net/ethernet/intel/ixgbevf/ixgbevf_main.c |  1 +
>   drivers/net/ethernet/marvell/mvneta.c         |  2 +
>   .../net/ethernet/marvell/mvpp2/mvpp2_main.c   |  3 ++
>   .../ethernet/marvell/octeontx2/nic/otx2_pf.c  |  9 ++++-
>   drivers/net/ethernet/mediatek/mtk_eth_soc.c   |  5 +++
>   .../net/ethernet/mellanox/mlx4/en_netdev.c    |  2 +
>   .../net/ethernet/mellanox/mlx5/core/en_main.c |  9 +++++
>   drivers/net/ethernet/microsoft/mana/mana_en.c |  1 +
>   .../ethernet/netronome/nfp/nfp_net_common.c   |  4 ++
>   drivers/net/ethernet/qlogic/qede/qede_main.c  |  2 +
>   drivers/net/ethernet/sfc/efx.c                |  3 ++
>   drivers/net/ethernet/sfc/siena/efx.c          |  3 ++
>   drivers/net/ethernet/socionext/netsec.c       |  2 +
>   .../net/ethernet/stmicro/stmmac/stmmac_main.c |  1 +
>   drivers/net/ethernet/ti/cpsw.c                |  2 +
>   drivers/net/ethernet/ti/cpsw_new.c            |  3 ++
>   drivers/net/hyperv/netvsc_drv.c               |  2 +
>   drivers/net/netdevsim/netdev.c                |  1 +
>   drivers/net/tun.c                             |  4 ++
>   drivers/net/veth.c                            |  3 ++
>   drivers/net/virtio_net.c                      |  5 +++
>   drivers/net/xen-netfront.c                    |  1 +
>   include/net/xdp.h                             | 39 +++++++++++++++++++
>   38 files changed, 164 insertions(+), 5 deletions(-)

> diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c  
> b/drivers/net/ethernet/amazon/ena/ena_netdev.c
> index e8ad5ea31aff..e8aeae70675a 100644
> --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
> +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
> @@ -597,7 +597,10 @@ static int ena_xdp_set(struct net_device *netdev,  
> struct netdev_bpf *bpf)
>   				if (rc)
>   					return rc;
>   			}
> +			__xdp_features_set_redirect_target(&netdev->xdp_features,
> +							   NETDEV_XDP_ACT_NDO_XMIT);
>   		} else if (old_bpf_prog) {
> +			xdp_features_clear_redirect_target(&netdev->xdp_features);
>   			rc = ena_destroy_and_free_all_xdp_queues(adapter);
>   			if (rc)
>   				return rc;
> @@ -4103,6 +4106,8 @@ static void ena_set_conf_feat_params(struct  
> ena_adapter *adapter,
>   	/* Set offload features */
>   	ena_set_dev_offloads(feat, netdev);

> +	netdev->xdp_features = NETDEV_XDP_ACT_FULL;
> +
>   	adapter->max_mtu = feat->dev_attr.max_mtu;
>   	netdev->max_mtu = adapter->max_mtu;
>   	netdev->min_mtu = ENA_MIN_MTU;
> diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c  
> b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> index 06508eebb585..3fc9a702083c 100644
> --- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> +++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> @@ -384,6 +384,10 @@ void aq_nic_ndev_init(struct aq_nic_s *self)
>   	self->ndev->mtu = aq_nic_cfg->mtu - ETH_HLEN;
>   	self->ndev->max_mtu = aq_hw_caps->mtu - ETH_FCS_LEN - ETH_HLEN;

> +	self->ndev->xdp_features = NETDEV_XDP_ACT_FULL |
> +				   NETDEV_XDP_ACT_NDO_XMIT |
> +				   NETDEV_XDP_ACT_RX_SG |
> +				   NETDEV_XDP_ACT_NDO_XMIT_SG;
>   }

>   void aq_nic_set_tx_ring(struct aq_nic_s *self, unsigned int idx,
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c  
> b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index 16ce7a90610c..333636d83620 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -13686,6 +13686,8 @@ static int bnxt_init_one(struct pci_dev *pdev,  
> const struct pci_device_id *ent)

>   	netif_set_tso_max_size(dev, GSO_MAX_SIZE);

> +	dev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_RX_SG;
> +
>   #ifdef CONFIG_BNXT_SRIOV
>   	init_waitqueue_head(&bp->sriov_cfg_wait);
>   #endif
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c  
> b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> index 36d5202c0aee..b701d6b5a405 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
> @@ -422,9 +422,11 @@ static int bnxt_xdp_set(struct bnxt *bp, struct  
> bpf_prog *prog)

>   	if (prog) {
>   		bnxt_set_rx_skb_mode(bp, true);
> +		xdp_features_set_redirect_target(&dev->xdp_features);
>   	} else {
>   		int rx, tx;

> +		xdp_features_clear_redirect_target(&dev->xdp_features);
>   		bnxt_set_rx_skb_mode(bp, false);
>   		bnxt_get_max_rings(bp, &rx, &tx, true);
>   		if (rx > 1) {
> diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c  
> b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> index f2f95493ec89..8b25313c7f6b 100644
> --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> @@ -2218,6 +2218,8 @@ static int nicvf_probe(struct pci_dev *pdev, const  
> struct pci_device_id *ent)
>   	netdev->netdev_ops = &nicvf_netdev_ops;
>   	netdev->watchdog_timeo = NICVF_TX_TIMEOUT;

> +	netdev->xdp_features = NETDEV_XDP_ACT_BASIC;
> +
>   	/* MTU range: 64 - 9200 */
>   	netdev->min_mtu = NIC_HW_MIN_FRS;
>   	netdev->max_mtu = NIC_HW_MAX_FRS;
> diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c  
> b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
> index 3f8032947d86..f6e1b270b6d0 100644
> --- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
> +++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
> @@ -244,6 +244,8 @@ static int dpaa_netdev_init(struct net_device  
> *net_dev,
>   	net_dev->features |= net_dev->hw_features;
>   	net_dev->vlan_features = net_dev->features;

> +	net_dev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	if (is_valid_ether_addr(mac_addr)) {
>   		memcpy(net_dev->perm_addr, mac_addr, net_dev->addr_len);
>   		eth_hw_addr_set(net_dev, mac_addr);
> diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c  
> b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> index 0c35abb7d065..8c51c59d3c86 100644
> --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> @@ -4593,6 +4593,8 @@ static int dpaa2_eth_netdev_init(struct net_device  
> *net_dev)
>   			    NETIF_F_LLTX | NETIF_F_HW_TC | NETIF_F_TSO;
>   	net_dev->gso_max_segs = DPAA2_ETH_ENQUEUE_MAX_FDS;
>   	net_dev->hw_features = net_dev->features;
> +	net_dev->xdp_features = NETDEV_XDP_ACT_FULL_ZC |
> +				NETDEV_XDP_ACT_NDO_XMIT;

>   	if (priv->dpni_attrs.vlan_filter_entries)
>   		net_dev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c  
> b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> index 9f6c4f5c0a6c..5f481985d3c1 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> @@ -825,6 +825,8 @@ static void enetc_pf_netdev_setup(struct enetc_si  
> *si, struct net_device *ndev,
>   		ndev->hw_features |= NETIF_F_RXHASH;

>   	ndev->priv_flags |= IFF_UNICAST_FLT;
> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT |
> +			     NETDEV_XDP_ACT_RX_SG | NETDEV_XDP_ACT_NDO_XMIT_SG;

>   	if (si->hw_features & ENETC_SI_F_PSFP && !enetc_psfp_enable(priv)) {
>   		priv->active_offloads |= ENETC_F_QCI;
> diff --git a/drivers/net/ethernet/fungible/funeth/funeth_main.c  
> b/drivers/net/ethernet/fungible/funeth/funeth_main.c
> index b4cce30e526a..003411b33a92 100644
> --- a/drivers/net/ethernet/fungible/funeth/funeth_main.c
> +++ b/drivers/net/ethernet/fungible/funeth/funeth_main.c
> @@ -1160,6 +1160,11 @@ static int fun_xdp_setup(struct net_device *dev,  
> struct netdev_bpf *xdp)
>   			WRITE_ONCE(rxqs[i]->xdp_prog, prog);
>   	}

> +	if (prog)
> +		xdp_features_set_redirect_target(&dev->xdp_features);
> +	else
> +		xdp_features_clear_redirect_target(&dev->xdp_features);
> +
>   	dev->max_mtu = prog ? XDP_MAX_MTU : FUN_MAX_MTU;
>   	old_prog = xchg(&fp->xdp_prog, prog);
>   	if (old_prog)
> @@ -1765,6 +1770,7 @@ static int fun_create_netdev(struct fun_ethdev *ed,  
> unsigned int portid)
>   	netdev->vlan_features = netdev->features & VLAN_FEAT;
>   	netdev->mpls_features = netdev->vlan_features;
>   	netdev->hw_enc_features = netdev->hw_features;
> +	netdev->xdp_features = NETDEV_XDP_ACT_FULL;

>   	netdev->min_mtu = ETH_MIN_MTU;
>   	netdev->max_mtu = FUN_MAX_MTU;
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c  
> b/drivers/net/ethernet/intel/i40e/i40e_main.c
> index 53d0083e35da..39f8ab2a22e6 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_main.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
> @@ -13339,9 +13339,11 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi,  
> struct bpf_prog *prog,
>   	old_prog = xchg(&vsi->xdp_prog, prog);

>   	if (need_reset) {
> -		if (!prog)
> +		if (!prog) {
> +			xdp_features_clear_redirect_target(&vsi->netdev->xdp_features);
>   			/* Wait until ndo_xsk_wakeup completes. */
>   			synchronize_rcu();
> +		}
>   		i40e_reset_and_rebuild(pf, true, true);
>   	}

> @@ -13362,11 +13364,13 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi,  
> struct bpf_prog *prog,
>   	/* Kick start the NAPI context if there is an AF_XDP socket open
>   	 * on that queue id. This so that receiving will start.
>   	 */
> -	if (need_reset && prog)
> +	if (need_reset && prog) {
>   		for (i = 0; i < vsi->num_queue_pairs; i++)
>   			if (vsi->xdp_rings[i]->xsk_pool)
>   				(void)i40e_xsk_wakeup(vsi->netdev, i,
>   						      XDP_WAKEUP_RX);
> +		xdp_features_set_redirect_target(&vsi->netdev->xdp_features);
> +	}

>   	return 0;
>   }
> @@ -13783,6 +13787,7 @@ static int i40e_config_netdev(struct i40e_vsi  
> *vsi)
>   	netdev->hw_enc_features |= NETIF_F_TSO_MANGLEID;

>   	netdev->features &= ~NETIF_F_HW_TC;
> +	netdev->xdp_features = NETDEV_XDP_ACT_ZC;

>   	if (vsi->type == I40E_VSI_MAIN) {
>   		SET_NETDEV_DEV(netdev, &pf->pdev->dev);
> diff --git a/drivers/net/ethernet/intel/ice/ice_main.c  
> b/drivers/net/ethernet/intel/ice/ice_main.c
> index a9a7f8b52140..0c9c75fa2349 100644
> --- a/drivers/net/ethernet/intel/ice/ice_main.c
> +++ b/drivers/net/ethernet/intel/ice/ice_main.c
> @@ -22,6 +22,7 @@
>   #include "ice_eswitch.h"
>   #include "ice_tc_lib.h"
>   #include "ice_vsi_vlan_ops.h"
> +#include <net/xdp_sock_drv.h>

>   #define DRV_SUMMARY	"Intel(R) Ethernet Connection E800 Series Linux  
> Driver"
>   static const char ice_driver_string[] = DRV_SUMMARY;
> @@ -2899,11 +2900,14 @@ ice_xdp_setup_prog(struct ice_vsi *vsi, struct  
> bpf_prog *prog,
>   			if (xdp_ring_err)
>   				NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Tx resources failed");
>   		}
> +		__xdp_features_set_redirect_target(&vsi->netdev->xdp_features,
> +						   NETDEV_XDP_ACT_NDO_XMIT);
>   		/* reallocate Rx queues that are used for zero-copy */
>   		xdp_ring_err = ice_realloc_zc_buf(vsi, true);
>   		if (xdp_ring_err)
>   			NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Rx resources failed");
>   	} else if (ice_is_xdp_ena_vsi(vsi) && !prog) {
> +		xdp_features_clear_redirect_target(&vsi->netdev->xdp_features);
>   		xdp_ring_err = ice_destroy_xdp_rings(vsi);
>   		if (xdp_ring_err)
>   			NL_SET_ERR_MSG_MOD(extack, "Freeing XDP Tx resources failed");
> @@ -3446,6 +3450,7 @@ static int ice_cfg_netdev(struct ice_vsi *vsi)
>   	np->vsi = vsi;

>   	ice_set_netdev_features(netdev);
> +	netdev->xdp_features = NETDEV_XDP_ACT_ZC;

>   	ice_set_ops(netdev);

> diff --git a/drivers/net/ethernet/intel/igb/igb_main.c  
> b/drivers/net/ethernet/intel/igb/igb_main.c
> index 3c0c35ecea10..a20cc52a52d6 100644
> --- a/drivers/net/ethernet/intel/igb/igb_main.c
> +++ b/drivers/net/ethernet/intel/igb/igb_main.c
> @@ -2871,8 +2871,14 @@ static int igb_xdp_setup(struct net_device *dev,  
> struct netdev_bpf *bpf)
>   		bpf_prog_put(old_prog);

>   	/* bpf is just replaced, RXQ and MTU are already setup */
> -	if (!need_reset)
> +	if (!need_reset) {
>   		return 0;
> +	} else {
> +		if (prog)
> +			xdp_features_set_redirect_target(&dev->xdp_features);
> +		else
> +			xdp_features_clear_redirect_target(&dev->xdp_features);
> +	}

>   	if (running)
>   		igb_open(dev);
> @@ -3317,6 +3323,7 @@ static int igb_probe(struct pci_dev *pdev, const  
> struct pci_device_id *ent)
>   	netdev->priv_flags |= IFF_SUPP_NOFCS;

>   	netdev->priv_flags |= IFF_UNICAST_FLT;
> +	netdev->xdp_features = NETDEV_XDP_ACT_FULL;

>   	/* MTU range: 68 - 9216 */
>   	netdev->min_mtu = ETH_MIN_MTU;
> diff --git a/drivers/net/ethernet/intel/igc/igc_main.c  
> b/drivers/net/ethernet/intel/igc/igc_main.c
> index e86b15efaeb8..3702c3cea383 100644
> --- a/drivers/net/ethernet/intel/igc/igc_main.c
> +++ b/drivers/net/ethernet/intel/igc/igc_main.c
> @@ -6533,6 +6533,8 @@ static int igc_probe(struct pci_dev *pdev,
>   	netdev->mpls_features |= NETIF_F_HW_CSUM;
>   	netdev->hw_enc_features |= netdev->vlan_features;

> +	netdev->xdp_features = NETDEV_XDP_ACT_ZC;
> +
>   	/* MTU range: 68 - 9216 */
>   	netdev->min_mtu = ETH_MIN_MTU;
>   	netdev->max_mtu = MAX_STD_JUMBO_FRAME_SIZE;
> diff --git a/drivers/net/ethernet/intel/igc/igc_xdp.c  
> b/drivers/net/ethernet/intel/igc/igc_xdp.c
> index aeeb34e64610..570170a29e3a 100644
> --- a/drivers/net/ethernet/intel/igc/igc_xdp.c
> +++ b/drivers/net/ethernet/intel/igc/igc_xdp.c
> @@ -29,6 +29,11 @@ int igc_xdp_set_prog(struct igc_adapter *adapter,  
> struct bpf_prog *prog,
>   	if (old_prog)
>   		bpf_prog_put(old_prog);

> +	if (prog)
> +		xdp_features_set_redirect_target(&dev->xdp_features);
> +	else
> +		xdp_features_clear_redirect_target(&dev->xdp_features);
> +
>   	if (if_running)
>   		igc_open(dev);

> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c  
> b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index ab8370c413f3..ae018a80d140 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -10301,6 +10301,8 @@ static int ixgbe_xdp_setup(struct net_device  
> *dev, struct bpf_prog *prog)
>   			rcu_assign_pointer(adapter->xdp_prog, old_prog);
>   			return -EINVAL;
>   		}
> +		if (!prog)
> +			xdp_features_clear_redirect_target(&dev->xdp_features);
>   	} else {
>   		for (i = 0; i < adapter->num_rx_queues; i++)
>   			(void)xchg(&adapter->rx_ring[i]->xdp_prog,
> @@ -10320,6 +10322,7 @@ static int ixgbe_xdp_setup(struct net_device  
> *dev, struct bpf_prog *prog)
>   			if (adapter->xdp_ring[i]->xsk_pool)
>   				(void)ixgbe_xsk_wakeup(adapter->netdev, i,
>   						       XDP_WAKEUP_RX);
> +		xdp_features_set_redirect_target(&dev->xdp_features);
>   	}

>   	return 0;
> @@ -11017,6 +11020,8 @@ static int ixgbe_probe(struct pci_dev *pdev,  
> const struct pci_device_id *ent)
>   	netdev->priv_flags |= IFF_UNICAST_FLT;
>   	netdev->priv_flags |= IFF_SUPP_NOFCS;

> +	netdev->xdp_features = NETDEV_XDP_ACT_ZC;
> +
>   	/* MTU range: 68 - 9710 */
>   	netdev->min_mtu = ETH_MIN_MTU;
>   	netdev->max_mtu = IXGBE_MAX_JUMBO_FRAME_SIZE - (ETH_HLEN + ETH_FCS_LEN);
> diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c  
> b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> index ea0a230c1153..a44e4bd56142 100644
> --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> @@ -4634,6 +4634,7 @@ static int ixgbevf_probe(struct pci_dev *pdev,  
> const struct pci_device_id *ent)
>   			    NETIF_F_HW_VLAN_CTAG_TX;

>   	netdev->priv_flags |= IFF_UNICAST_FLT;
> +	netdev->xdp_features = NETDEV_XDP_ACT_BASIC;

>   	/* MTU range: 68 - 1504 or 9710 */
>   	netdev->min_mtu = ETH_MIN_MTU;
> diff --git a/drivers/net/ethernet/marvell/mvneta.c  
> b/drivers/net/ethernet/marvell/mvneta.c
> index f8925cac61e4..7ca49753d618 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -5612,6 +5612,8 @@ static int mvneta_probe(struct platform_device  
> *pdev)
>   			NETIF_F_TSO | NETIF_F_RXCSUM;
>   	dev->hw_features |= dev->features;
>   	dev->vlan_features |= dev->features;
> +	dev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT |
> +			    NETDEV_XDP_ACT_RX_SG | NETDEV_XDP_ACT_NDO_XMIT_SG;
>   	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
>   	netif_set_tso_max_segs(dev, MVNETA_MAX_TSO_SEGS);

> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c  
> b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index 4da45c5abba5..826423541d7a 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -6866,6 +6866,9 @@ static int mvpp2_port_probe(struct platform_device  
> *pdev,

>   	dev->vlan_features |= features;
>   	netif_set_tso_max_segs(dev, MVPP2_MAX_TSO_SEGS);
> +
> +	dev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	dev->priv_flags |= IFF_UNICAST_FLT;

>   	/* MTU range: 68 - 9704 */
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c  
> b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> index c1ea60bc2630..dd53bb315100 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> @@ -2512,10 +2512,14 @@ static int otx2_xdp_setup(struct otx2_nic *pf,  
> struct bpf_prog *prog)
>   	/* Network stack and XDP shared same rx queues.
>   	 * Use separate tx queues for XDP and network stack.
>   	 */
> -	if (pf->xdp_prog)
> +	if (pf->xdp_prog) {
>   		pf->hw.xdp_queues = pf->hw.rx_queues;
> -	else
> +		__xdp_features_set_redirect_target(&dev->xdp_features,
> +						   NETDEV_XDP_ACT_NDO_XMIT);
> +	} else {
>   		pf->hw.xdp_queues = 0;
> +		xdp_features_clear_redirect_target(&dev->xdp_features);
> +	}

>   	pf->hw.tot_tx_queues += pf->hw.xdp_queues;

> @@ -2878,6 +2882,7 @@ static int otx2_probe(struct pci_dev *pdev, const  
> struct pci_device_id *id)
>   	netdev->watchdog_timeo = OTX2_TX_TIMEOUT;

>   	netdev->netdev_ops = &otx2_netdev_ops;
> +	netdev->xdp_features = NETDEV_XDP_ACT_FULL;

>   	netdev->min_mtu = OTX2_MIN_MTU;
>   	netdev->max_mtu = otx2_get_max_mtu(pf);
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c  
> b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index e3de9a53b2d9..d960dd3841d7 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -4186,6 +4186,11 @@ static int mtk_add_mac(struct mtk_eth *eth, struct  
> device_node *np)
>   		register_netdevice_notifier(&mac->device_notifier);
>   	}

> +	if (mtk_page_pool_enabled(eth))
> +		eth->netdev[id]->xdp_features = NETDEV_XDP_ACT_FULL |
> +						NETDEV_XDP_ACT_NDO_XMIT |
> +						NETDEV_XDP_ACT_NDO_XMIT_SG;
> +
>   	return 0;

>   free_netdev:
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c  
> b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> index 8800d3f1f55c..77957db600cb 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
> @@ -3410,6 +3410,8 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev,  
> int port,
>   		priv->rss_hash_fn = ETH_RSS_HASH_TOP;
>   	}

> +	dev->xdp_features = NETDEV_XDP_ACT_FULL;
> +
>   	/* MTU range: 68 - hw-specific max */
>   	dev->min_mtu = ETH_MIN_MTU;
>   	dev->max_mtu = priv->max_mtu;
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c  
> b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> index cff5f2e29e1e..f50988c5d636 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -4776,6 +4776,13 @@ static int mlx5e_xdp_set(struct net_device  
> *netdev, struct bpf_prog *prog)
>   	if (old_prog)
>   		bpf_prog_put(old_prog);

> +	if (reset) {
> +		if (prog)
> +			xdp_features_set_redirect_target(&netdev->xdp_features);
> +		else
> +			xdp_features_clear_redirect_target(&netdev->xdp_features);
> +	}
> +
>   	if (!test_bit(MLX5E_STATE_OPENED, &priv->state) || reset)
>   		goto unlock;

> @@ -5170,6 +5177,8 @@ static void mlx5e_build_nic_netdev(struct  
> net_device *netdev)
>   	netdev->features         |= NETIF_F_HIGHDMA;
>   	netdev->features         |= NETIF_F_HW_VLAN_STAG_FILTER;

> +	netdev->xdp_features = NETDEV_XDP_ACT_ZC | NETDEV_XDP_ACT_RX_SG;
> +
>   	netdev->priv_flags       |= IFF_UNICAST_FLT;

>   	netif_set_tso_max_size(netdev, GSO_MAX_SIZE);
> diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c  
> b/drivers/net/ethernet/microsoft/mana/mana_en.c
> index 2f6a048dee90..25f21942aa20 100644
> --- a/drivers/net/ethernet/microsoft/mana/mana_en.c
> +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
> @@ -2160,6 +2160,7 @@ static int mana_probe_port(struct mana_context *ac,  
> int port_idx,
>   	ndev->hw_features |= NETIF_F_RXHASH;
>   	ndev->features = ndev->hw_features;
>   	ndev->vlan_features = 0;
> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;

>   	err = register_netdev(ndev);
>   	if (err) {
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c  
> b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> index 18fc9971f1c8..5a8ddeaff74d 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> @@ -2529,10 +2529,14 @@ static void nfp_net_netdev_init(struct nfp_net  
> *nn)
>   	netdev->features &= ~NETIF_F_HW_VLAN_STAG_RX;
>   	nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_RXQINQ;

> +	nn->dp.netdev->xdp_features = NETDEV_XDP_ACT_BASIC |
> +				      NETDEV_XDP_ACT_HW_OFFLOAD;
> +
>   	/* Finalise the netdev setup */
>   	switch (nn->dp.ops->version) {
>   	case NFP_NFD_VER_NFD3:
>   		netdev->netdev_ops = &nfp_nfd3_netdev_ops;
> +		nn->dp.netdev->xdp_features |= NETDEV_XDP_ACT_XSK_ZEROCOPY;
>   		break;
>   	case NFP_NFD_VER_NFDK:
>   		netdev->netdev_ops = &nfp_nfdk_netdev_ops;
> diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c  
> b/drivers/net/ethernet/qlogic/qede/qede_main.c
> index 953f304b8588..a8ad2b8386d3 100644
> --- a/drivers/net/ethernet/qlogic/qede/qede_main.c
> +++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
> @@ -892,6 +892,8 @@ static void qede_init_ndev(struct qede_dev *edev)

>   	ndev->hw_features = hw_features;

> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	/* MTU range: 46 - 9600 */
>   	ndev->min_mtu = ETH_ZLEN - ETH_HLEN;
>   	ndev->max_mtu = QEDE_MAX_JUMBO_PACKET_SIZE;
> diff --git a/drivers/net/ethernet/sfc/efx.c  
> b/drivers/net/ethernet/sfc/efx.c
> index 0556542d7a6b..60b2183681ce 100644
> --- a/drivers/net/ethernet/sfc/efx.c
> +++ b/drivers/net/ethernet/sfc/efx.c
> @@ -1078,6 +1078,9 @@ static int efx_pci_probe(struct pci_dev *pci_dev,

>   	pci_info(pci_dev, "Solarflare NIC detected\n");

> +	efx->net_dev->xdp_features = NETDEV_XDP_ACT_FULL |
> +				     NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	if (!efx->type->is_vf)
>   		efx_probe_vpd_strings(efx);

> diff --git a/drivers/net/ethernet/sfc/siena/efx.c  
> b/drivers/net/ethernet/sfc/siena/efx.c
> index 60e5b7c8ccf9..175c999bebc1 100644
> --- a/drivers/net/ethernet/sfc/siena/efx.c
> +++ b/drivers/net/ethernet/sfc/siena/efx.c
> @@ -1048,6 +1048,9 @@ static int efx_pci_probe(struct pci_dev *pci_dev,

>   	pci_info(pci_dev, "Solarflare NIC detected\n");

> +	efx->net_dev->xdp_features = NETDEV_XDP_ACT_FULL |
> +				     NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	if (!efx->type->is_vf)
>   		efx_probe_vpd_strings(efx);

> diff --git a/drivers/net/ethernet/socionext/netsec.c  
> b/drivers/net/ethernet/socionext/netsec.c
> index 9b46579b5a10..4d6f17efa227 100644
> --- a/drivers/net/ethernet/socionext/netsec.c
> +++ b/drivers/net/ethernet/socionext/netsec.c
> @@ -2104,6 +2104,8 @@ static int netsec_probe(struct platform_device  
> *pdev)
>   				NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
>   	ndev->hw_features = ndev->features;

> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;
> +
>   	priv->rx_cksum_offload_flag = true;

>   	ret = netsec_register_mdio(priv, phy_addr);
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  
> b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index c6951c976f5d..316574ce3aa0 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -7145,6 +7145,7 @@ int stmmac_dvr_probe(struct device *device,

>   	ndev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
>   			    NETIF_F_RXCSUM;
> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;

>   	ret = stmmac_tc_init(priv, priv);
>   	if (!ret) {
> diff --git a/drivers/net/ethernet/ti/cpsw.c  
> b/drivers/net/ethernet/ti/cpsw.c
> index 13c9c2d6b79b..68b89c56d8b6 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -1458,6 +1458,7 @@ static int cpsw_probe_dual_emac(struct cpsw_priv  
> *priv)
>   	priv_sl2->emac_port = 1;
>   	cpsw->slaves[1].ndev = ndev;
>   	ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_CTAG_RX;
> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;

>   	ndev->netdev_ops = &cpsw_netdev_ops;
>   	ndev->ethtool_ops = &cpsw_ethtool_ops;
> @@ -1635,6 +1636,7 @@ static int cpsw_probe(struct platform_device *pdev)
>   	cpsw->slaves[0].ndev = ndev;

>   	ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_CTAG_RX;
> +	ndev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;

>   	ndev->netdev_ops = &cpsw_netdev_ops;
>   	ndev->ethtool_ops = &cpsw_ethtool_ops;
> diff --git a/drivers/net/ethernet/ti/cpsw_new.c  
> b/drivers/net/ethernet/ti/cpsw_new.c
> index 83596ec0c7cb..1cf8c6202e05 100644
> --- a/drivers/net/ethernet/ti/cpsw_new.c
> +++ b/drivers/net/ethernet/ti/cpsw_new.c
> @@ -1405,6 +1405,9 @@ static int cpsw_create_ports(struct cpsw_common  
> *cpsw)
>   		ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER |
>   				  NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_NETNS_LOCAL | NETIF_F_HW_TC;

> +		ndev->xdp_features = NETDEV_XDP_ACT_FULL |
> +				     NETDEV_XDP_ACT_NDO_XMIT;
> +
>   		ndev->netdev_ops = &cpsw_netdev_ops;
>   		ndev->ethtool_ops = &cpsw_ethtool_ops;
>   		SET_NETDEV_DEV(ndev, dev);
> diff --git a/drivers/net/hyperv/netvsc_drv.c  
> b/drivers/net/hyperv/netvsc_drv.c
> index f9b219e6cd58..c7c1ce6ca201 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -2559,6 +2559,8 @@ static int netvsc_probe(struct hv_device *dev,

>   	netdev_lockdep_set_classes(net);

> +	net->xdp_features = NETDEV_XDP_ACT_FULL;
> +
>   	/* MTU range: 68 - 1500 or 65521 */
>   	net->min_mtu = NETVSC_MTU_MIN;
>   	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
> diff --git a/drivers/net/netdevsim/netdev.c  
> b/drivers/net/netdevsim/netdev.c
> index 6db6a75ff9b9..35fa1ca98671 100644
> --- a/drivers/net/netdevsim/netdev.c
> +++ b/drivers/net/netdevsim/netdev.c
> @@ -286,6 +286,7 @@ static void nsim_setup(struct net_device *dev)
>   			 NETIF_F_TSO;
>   	dev->hw_features |= NETIF_F_HW_TC;
>   	dev->max_mtu = ETH_MAX_MTU;
> +	dev->xdp_features = NETDEV_XDP_ACT_HW_OFFLOAD;
>   }

>   static int nsim_init_netdevsim(struct netdevsim *ns)
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index a7d17c680f4a..fc041cff75e4 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -1401,6 +1401,10 @@ static void tun_net_initialize(struct net_device  
> *dev)

>   		eth_hw_addr_random(dev);

> +		/* Currently tun does not support XDP, only tap does. */
> +		dev->xdp_features = NETDEV_XDP_ACT_FULL |
> +				    NETDEV_XDP_ACT_NDO_XMIT;
> +
>   		break;
>   	}

> diff --git a/drivers/net/veth.c b/drivers/net/veth.c
> index dfc7d87fad59..01f7b38888a0 100644
> --- a/drivers/net/veth.c
> +++ b/drivers/net/veth.c
> @@ -1649,6 +1649,9 @@ static void veth_setup(struct net_device *dev)
>   	dev->hw_enc_features = VETH_FEATURES;
>   	dev->mpls_features = NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE;
>   	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
> +
> +	dev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT |
> +			    NETDEV_XDP_ACT_RX_SG | NETDEV_XDP_ACT_NDO_XMIT_SG;
>   }

>   /*
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 7723b2a49d8e..0721dff8c82c 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -3155,7 +3155,11 @@ static int virtnet_xdp_set(struct net_device *dev,  
> struct bpf_prog *prog,
>   			if (i == 0 && !old_prog)
>   				virtnet_clear_guest_offloads(vi);
>   		}
> +		if (!old_prog)
> +			__xdp_features_set_redirect_target(&dev->xdp_features,
> +							   NETDEV_XDP_ACT_NDO_XMIT);
>   	} else {
> +		xdp_features_clear_redirect_target(&dev->xdp_features);
>   		vi->xdp_enabled = false;
>   	}

> @@ -3785,6 +3789,7 @@ static int virtnet_probe(struct virtio_device *vdev)
>   		dev->hw_features |= NETIF_F_GRO_HW;

>   	dev->vlan_features = dev->features;
> +	dev->xdp_features = NETDEV_XDP_ACT_FULL;

>   	/* MTU range: 68 - 65535 */
>   	dev->min_mtu = MIN_MTU;
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index 14aec417fa06..58f0cbbadc90 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -1741,6 +1741,7 @@ static struct net_device *xennet_create_dev(struct  
> xenbus_device *dev)
>            * negotiate with the backend regarding supported features.
>            */
>   	netdev->features |= netdev->hw_features;
> +	netdev->xdp_features = NETDEV_XDP_ACT_FULL | NETDEV_XDP_ACT_NDO_XMIT;

>   	netdev->ethtool_ops = &xennet_ethtool_ops;
>   	netdev->min_mtu = ETH_MIN_MTU;
> diff --git a/include/net/xdp.h b/include/net/xdp.h
> index 3d37460f0bdb..c3a8f17c0310 100644
> --- a/include/net/xdp.h
> +++ b/include/net/xdp.h
> @@ -410,6 +410,45 @@ struct netdev_bpf;
>   void xdp_attachment_setup(struct xdp_attachment_info *info,
>   			  struct netdev_bpf *bpf);

> +#if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL)
> +
> +static inline void
> +__xdp_features_set_redirect_target(xdp_features_t *xdp_features, u32  
> flags)
> +{
> +	flags &= (NETDEV_XDP_ACT_NDO_XMIT | NETDEV_XDP_ACT_NDO_XMIT_SG);
> +	WRITE_ONCE(*xdp_features, *xdp_features | flags);

Maybe stupid question: why do we need WRITE_ONCE here?
And if we do need it, do we need READ_ONCE as well?

WRITE_ONCE(*xdp_features, READ_ONCE(*xdp_features) | flags);

?

Also, would it make sense to drop this __xdp_features_set_redirect_target
and just define the following:

static inline void
xdp_features_set_redirect_target(xdp_features_t *xdp_features, bool  
support_sg)
{
	xdp_features_t flags = NETDEV_XDP_ACT_NDO_XMIT;

	if (support_sg)
		flags |= NETDEV_XDP_ACT_NDO_XMIT_SG;
	*xdp_features |= flags; /* or WRITE_ONCE */
}

This should avoid having two different sets of functions. Or does it
look worse because of that 'naked' true/false argument in the call
sites?


> +}
> +
> +static inline void
> +xdp_features_clear_redirect_target(xdp_features_t *xdp_features)
> +{
> +	WRITE_ONCE(*xdp_features,
> +		   *xdp_features & ~(NETDEV_XDP_ACT_NDO_XMIT |
> +				     NETDEV_XDP_ACT_NDO_XMIT_SG));
> +}
> +
> +#else
> +
> +static inline void
> +__xdp_features_set_redirect_target(xdp_features_t *xdp_features, u32  
> flags)
> +{
> +}
> +
> +static inline void
> +xdp_features_clear_redirect_target(xdp_features_t *xdp_features)
> +{
> +}
> +
> +#endif
> +
> +static inline void
> +xdp_features_set_redirect_target(xdp_features_t *xdp_features)
> +{
> +	__xdp_features_set_redirect_target(xdp_features,
> +					   NETDEV_XDP_ACT_NDO_XMIT |
> +					   NETDEV_XDP_ACT_NDO_XMIT_SG);
> +}
> +
>   #define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE

>   #endif /* __LINUX_NET_XDP_H__ */
> --
> 2.39.0

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