Re: [PATCH net-next v4 2/6] net: ti: icssg-prueth: Add XSK pool helpers

[Paolo Abeni <pabeni@redhat.com>]

On 10/23/25 11:39 AM, Meghana Malladi wrote:
> @@ -1200,6 +1218,109 @@ static int emac_xdp_setup(struct prueth_emac *emac, struct netdev_bpf *bpf)
>  	return 0;
>  }
>  
> +static int prueth_xsk_pool_enable(struct prueth_emac *emac,
> +				  struct xsk_buff_pool *pool, u16 queue_id)
> +{
> +	struct prueth_rx_chn *rx_chn = &emac->rx_chns;
> +	u32 frame_size;
> +	int ret;
> +
> +	if (queue_id >= PRUETH_MAX_RX_FLOWS ||
> +	    queue_id >= emac->tx_ch_num) {
> +		netdev_err(emac->ndev, "Invalid XSK queue ID %d\n", queue_id);
> +		return -EINVAL;
> +	}
> +
> +	frame_size = xsk_pool_get_rx_frame_size(pool);
> +	if (frame_size < PRUETH_MAX_PKT_SIZE)
> +		return -EOPNOTSUPP;
> +
> +	ret = xsk_pool_dma_map(pool, rx_chn->dma_dev, PRUETH_RX_DMA_ATTR);
> +	if (ret) {
> +		netdev_err(emac->ndev, "Failed to map XSK pool: %d\n", ret);
> +		return ret;
> +	}
> +
> +	if (netif_running(emac->ndev)) {
> +		/* stop packets from wire for graceful teardown */
> +		ret = icssg_set_port_state(emac, ICSSG_EMAC_PORT_DISABLE);
> +		if (ret)
> +			return ret;
> +		prueth_destroy_rxq(emac);
> +	}
> +
> +	emac->xsk_qid = queue_id;
> +	prueth_set_xsk_pool(emac, queue_id);
> +
> +	if (netif_running(emac->ndev)) {
> +		ret = prueth_create_rxq(emac);

It looks like this falls short of Jakub's request on v2:

https://lore.kernel.org/netdev/20250903174847.5d8d1c9f@kernel.org/

about not freeing the rx queue for reconfig.

I think you should:
- stop the H/W from processing incoming packets,
- spool all the pending packets
- attach/detach the xsk_pool
- refill the ring
- re-enable the H/W

/P