Re: [PATCH net-next v3 4/7] net: lan966x: Update rxq memory model

Alexander Lobakin
2022-11-22T11:42:21Z

From: Horatiu Vultur <horatiu.vultur@microchip.com>
Date: Mon, 21 Nov 2022 22:28:47 +0100

> By default the rxq memory model is MEM_TYPE_PAGE_SHARED but to be able
> to reuse pages on the TX side, when the XDP action XDP_TX it is required
> to update the memory model to PAGE_POOL.
>
> Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> ---
> .../net/ethernet/microchip/lan966x/lan966x_fdma.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> index 384ed34197d58..483d1470c8362 100644
> --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
> @@ -78,8 +78,22 @@ static int lan966x_fdma_rx_alloc_page_pool(struct lan966x_rx *rx)
> .max_len = rx->max_mtu -
> SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
> };
> + struct lan966x_port *port;
> + int i;
>
> rx->page_pool = page_pool_create(&pp_params);
> +
> + for (i = 0; i < lan966x->num_phys_ports; ++i) {
> + if (!lan966x->ports[i])
> + continue;
> +
> + port = lan966x->ports[i];
> +
> + xdp_rxq_info_unreg_mem_model(&port->xdp_rxq);

xdp_rxq_info_unreg_mem_model() can emit a splat if currently the
corresponding xdp_rxq_info is not registered[0]. Can't we face it
here if called from lan966x_fdma_init()?

> + xdp_rxq_info_reg_mem_model(&port->xdp_rxq, MEM_TYPE_PAGE_POOL,
> + rx->page_pool);
> + }
> +
> return PTR_ERR_OR_ZERO(rx->page_pool);
> }
>
> --
> 2.38.0

Thanks,
Olek