1 files changed, 47 insertions, 6 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 214eebb7bbd8..ccd9b9514001 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -44,6 +44,8 @@ MODULE_PARM_DESC(debug, "netif level (0=none,...,16=all)");
 #endif /* !CONFIG_DYNAMIC_DEBUG */
 
 static DEFINE_IDA(ice_aux_ida);
+DEFINE_STATIC_KEY_FALSE(ice_xdp_locking_key);
+EXPORT_SYMBOL(ice_xdp_locking_key);
 
 static struct workqueue_struct *ice_wq;
 static const struct net_device_ops ice_netdev_safe_mode_ops;
@@ -2397,14 +2399,19 @@ static int ice_xdp_alloc_setup_rings(struct ice_vsi *vsi)
 			goto free_xdp_rings;
 		ice_set_ring_xdp(xdp_ring);
 		xdp_ring->xsk_pool = ice_tx_xsk_pool(xdp_ring);
+		spin_lock_init(&xdp_ring->tx_lock);
 		for (j = 0; j < xdp_ring->count; j++) {
 			tx_desc = ICE_TX_DESC(xdp_ring, j);
 			tx_desc->cmd_type_offset_bsz = cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE);
 		}
 	}
 
-	ice_for_each_rxq(vsi, i)
-		vsi->rx_rings[i]->xdp_ring = vsi->xdp_rings[i];
+	ice_for_each_rxq(vsi, i) {
+		if (static_key_enabled(&ice_xdp_locking_key))
+			vsi->rx_rings[i]->xdp_ring = vsi->xdp_rings[i % vsi->num_xdp_txq];
+		else
+			vsi->rx_rings[i]->xdp_ring = vsi->xdp_rings[i];
+	}
 
 	return 0;
 
@@ -2469,6 +2476,10 @@ int ice_prepare_xdp_rings(struct ice_vsi *vsi, struct bpf_prog *prog)
 	if (__ice_vsi_get_qs(&xdp_qs_cfg))
 		goto err_map_xdp;
 
+	if (static_key_enabled(&ice_xdp_locking_key))
+		netdev_warn(vsi->netdev,
+			    "Could not allocate one XDP Tx ring per CPU, XDP_TX/XDP_REDIRECT actions will be slower\n");
+
 	if (ice_xdp_alloc_setup_rings(vsi))
 		goto clear_xdp_rings;
 
@@ -2585,6 +2596,9 @@ free_qmap:
 	devm_kfree(ice_pf_to_dev(pf), vsi->xdp_rings);
 	vsi->xdp_rings = NULL;
 
+	if (static_key_enabled(&ice_xdp_locking_key))
+		static_branch_dec(&ice_xdp_locking_key);
+
 	if (ice_is_reset_in_progress(pf->state) || !vsi->q_vectors[0])
 		return 0;
 
@@ -2620,6 +2634,29 @@ static void ice_vsi_rx_napi_schedule(struct ice_vsi *vsi)
 }
 
 /**
+ * ice_vsi_determine_xdp_res - figure out how many Tx qs can XDP have
+ * @vsi: VSI to determine the count of XDP Tx qs
+ *
+ * returns 0 if Tx qs count is higher than at least half of CPU count,
+ * -ENOMEM otherwise
+ */
+int ice_vsi_determine_xdp_res(struct ice_vsi *vsi)
+{
+	u16 avail = ice_get_avail_txq_count(vsi->back);
+	u16 cpus = num_possible_cpus();
+
+	if (avail < cpus / 2)
+		return -ENOMEM;
+
+	vsi->num_xdp_txq = min_t(u16, avail, cpus);
+
+	if (vsi->num_xdp_txq < cpus)
+		static_branch_inc(&ice_xdp_locking_key);
+
+	return 0;
+}
+
+/**
  * ice_xdp_setup_prog - Add or remove XDP eBPF program
  * @vsi: VSI to setup XDP for
  * @prog: XDP program
@@ -2648,10 +2685,14 @@ ice_xdp_setup_prog(struct ice_vsi *vsi, struct bpf_prog *prog,
 	}
 
 	if (!ice_is_xdp_ena_vsi(vsi) && prog) {
-		vsi->num_xdp_txq = num_possible_cpus();
-		xdp_ring_err = ice_prepare_xdp_rings(vsi, prog);
-		if (xdp_ring_err)
-			NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Tx resources failed");
+		xdp_ring_err = ice_vsi_determine_xdp_res(vsi);
+		if (xdp_ring_err) {
+			NL_SET_ERR_MSG_MOD(extack, "Not enough Tx resources for XDP");
+		} else {
+			xdp_ring_err = ice_prepare_xdp_rings(vsi, prog);
+			if (xdp_ring_err)
+				NL_SET_ERR_MSG_MOD(extack, "Setting up XDP Tx resources failed");
+		}
 	} else if (ice_is_xdp_ena_vsi(vsi) && !prog) {
 		xdp_ring_err = ice_destroy_xdp_rings(vsi);
 		if (xdp_ring_err)