Re: [PATCH v6 2/2] net/af_xdp: Refactor af_xdp_tx_zc

[Stephen Hemminger <stephen@networkplumber.org>]

On Sat,  1 Feb 2025 00:10:21 +0100
Ariel Otilibili <ariel.otilibili@6wind.com> wrote:

> @ -559,21 +582,12 @@ af_xdp_tx_zc(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
>  		mbuf = bufs[i];
>  
>  		if (mbuf->pool == umem->mb_pool) {
> -			if (!xsk_ring_prod__reserve(&txq->tx, 1, &idx_tx)) {
> +			if (!(desc = reserve_and_fill(txq, mbuf, umem))) {
>  				kick_tx(txq, cq);
> -				if (!xsk_ring_prod__reserve(&txq->tx, 1,
> -							    &idx_tx))
> +				if (!(desc = reserve_and_fill(txq, mbuf, umem)))
>  					goto out;
>  			}

Please avoid doing assignment in a conditional statement, can be error prone.
Surprised checkpatch doesn't complain about it.

Better as:
			desc = reserve_and_fill(txq, mbuf, umem);
			if (!desc) {
				kick_tx(txq, cq);
				desc = reserve_and_fill(txq, mbuf, umem);
				if (!desc)
					goto out;