Re: [Intel-wired-lan] [PATCH iwl-next 03/10] ixgbevf: use libeth in Rx processing

Simon Horman
2026-02-24T17:46:01Z

On Mon, Feb 23, 2026 at 10:52:10AM +0100, Larysa Zaremba wrote:
> Use page_pool buffers by the means of libeth in the Rx queues, this
> significantly reduces code complexity of the driver itself.
>
> Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com>
> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>

...

> @@ -3257,12 +3133,26 @@ static int ixgbevf_setup_all_tx_resources(struct ixgbevf_adapter *adapter)
> int ixgbevf_setup_rx_resources(struct ixgbevf_adapter *adapter,
> struct ixgbevf_ring *rx_ring)
> {
> - int size;
> + struct libeth_fq fq = {
> + .count = rx_ring->count,
> + .nid = NUMA_NO_NODE,
> + .type = LIBETH_FQE_MTU,
> + .xdp = !!rx_ring->xdp_prog,
> + .idx = rx_ring->queue_index,
> + .buf_len = IXGBEVF_RX_PAGE_LEN(rx_ring->xdp_prog ?
> + LIBETH_XDP_HEADROOM :
> + LIBETH_SKB_HEADROOM),
> + };
> + int ret;
>
> - size = sizeof(struct ixgbevf_rx_buffer) * rx_ring->count;
> - rx_ring->rx_buffer_info = vmalloc(size);
> - if (!rx_ring->rx_buffer_info)
> - goto err;
> + ret = libeth_rx_fq_create(&fq, &rx_ring->q_vector->napi);
> + if (ret)
> + return ret;
> +
> + rx_ring->pp = fq.pp;
> + rx_ring->rx_fqes = fq.fqes;
> + rx_ring->truesize = fq.truesize;
> + rx_ring->rx_buf_len = fq.buf_len;
>
> u64_stats_init(&rx_ring->syncp);
>
> @@ -3270,25 +3160,29 @@ int ixgbevf_setup_rx_resources(struct ixgbevf_adapter *adapter,
> rx_ring->size = rx_ring->count * sizeof(union ixgbe_adv_rx_desc);
> rx_ring->size = ALIGN(rx_ring->size, 4096);
>
> - rx_ring->desc = dma_alloc_coherent(rx_ring->dev, rx_ring->size,
> + rx_ring->desc = dma_alloc_coherent(fq.pp->p.dev, rx_ring->size,
> &rx_ring->dma, GFP_KERNEL);
>
> if (!rx_ring->desc)

Hi Larysa,

Prior to this patch, if this error condition was met,
then function would return -ENOMEM. But now it will return 0.
This does not seem intentional.

Flagged by Smatch.

> goto err;
>
> /* XDP RX-queue info */
> - if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, adapter->netdev,
> - rx_ring->queue_index, 0) < 0)
> + ret = __xdp_rxq_info_reg(&rx_ring->xdp_rxq, adapter->netdev,
> + rx_ring->queue_index, 0, rx_ring->truesize);
> + if (ret)
> goto err;
>
> + xdp_rxq_info_attach_page_pool(&rx_ring->xdp_rxq, fq.pp);
> +
> rx_ring->xdp_prog = adapter->xdp_prog;
>
> return 0;
> err:
> - vfree(rx_ring->rx_buffer_info);
> - rx_ring->rx_buffer_info = NULL;
> + libeth_rx_fq_destroy(&fq);
> + rx_ring->rx_fqes = NULL;
> + rx_ring->pp = NULL;
> dev_err(rx_ring->dev, "Unable to allocate memory for the Rx descriptor ring\n");
> - return -ENOMEM;
> + return ret;
> }
>
> /**

...