Re: [net-next 10/13] net/mlx5e: Add support for XDP_REDIRECT in device-out side

[Tariq Toukan]

On 30/07/2018 3:10 PM, Jesper Dangaard Brouer wrote:

On Thu, 26 Jul 2018 15:56:44 -0700 Saeed Mahameed <sae...@mellanox.com> wrote:

+int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
+                  u32 flags)
+{
+       struct mlx5e_priv *priv = netdev_priv(dev);
+       struct mlx5e_xdpsq *sq;
+       int drops = 0;
+       int sq_num;
+       int i;
+
+       if (unlikely(!test_bit(MLX5E_STATE_OPENED, &priv->state)))
+               return -ENETDOWN;
+
+       if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
+               return -EINVAL;
+
+       sq_num = smp_processor_id();
+
+       if (unlikely(sq_num >= priv->channels.num))
+               return -ENXIO;
+
+       sq = &priv->channels.c[sq_num]->xdpsq;
+
+       if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
+               return -ENETDOWN;
+
+       for (i = 0; i < n; i++) {
+               struct xdp_frame *xdpf = frames[i];
+               struct mlx5e_xdp_info xdpi;
+
+               xdpi.dma_addr = dma_map_single(sq->pdev, xdpf->data, xdpf->len,
+                                              DMA_TO_DEVICE);
+               if (unlikely(dma_mapping_error(sq->pdev, xdpi.dma_addr))) {
+                       drops++;

I think you are missing a xdp_return_frame_rx_napi(xdpf) here.

Thanks for spotting this!
I'll fix.

+                       continue;
+               }
+
+               xdpi.xdpf = xdpf;
+
+               if (unlikely(!mlx5e_xmit_xdp_frame(sq, &xdpi))) {
+                       xdp_return_frame_rx_napi(xdpf);
+                       drops++;
+               }
+       }
+
+       if (flags & XDP_XMIT_FLUSH)
+               mlx5e_xmit_xdp_doorbell(sq);
+
+       return n - drops;
+}