Re: [PATCH net-next v4] net: mana: Use page pool fragments for RX buffers instead of full pages to improve memory efficiency.

[Jakub Kicinski]

On Mon, 11 Aug 2025 15:29:19 -0700 Dipayaan Roy wrote:
> -	if (apc->port_is_up)
> +	if (apc->port_is_up) {
> +		/* Re-create rxq's after xdp prog was loaded or unloaded.
> +		 * Ex: re create rxq's to switch from full pages to smaller
> +		 * size page fragments when xdp prog is unloaded and
> +		 * vice-versa.
> +		 */
> +
> +		/* Pre-allocate buffers to prevent failure in mana_attach */
> +		err = mana_pre_alloc_rxbufs(apc, ndev->mtu, apc->num_queues);
> +		if (err) {
> +			NL_SET_ERR_MSG_MOD
> +			    (extack,
> +			    "XDP: Insufficient memory for tx/rx re-config");

This weird line breaking is not necessary, checkpatch understands that
string can go over line limit:

			NL_SET_ERR_MSG_MOD(extack,
					   "XDP: Insufficient memory for tx/rx re-config");

> +			return err;

I think you already replaced the bpf program at this point? 
So the allocation should happen earlier. On failure changes
to the driver state should be undone.
-- 
pw-bot: cr