Re: [PATCH net-next 08/14] net: enetc: add multiple command BD rings support

Frank Li
2026-03-18T22:42:46Z

From: Frank Li (AI-BOT) <frank.li@nxp.com>

> +static struct netc_cbdr *netc_select_cbdr(struct ntmp_user *user)
> +{
> + int cpu, i;
> +
> + for (i = 0; i < user->cbdr_num; i++) {
> + if (spin_is_locked(&user->ring[i].ring_lock))
> + continue;
> +
> + return &user->ring[i];
> + }
> +
> + /* If all the command BDRs are busy now, we select
> + * one of them, but need to wait for a while to use.
> + */
> + cpu = smp_processor_id();
> +
> + return &user->ring[cpu % user->cbdr_num];
> +}

AI: spin_is_locked() is not reliable for lockless checks on all architectures.
Consider using spin_trylock() instead, or document why this racy check isi
acceptable here.

> + if (user->cbdr_num == 1)
> + cbdr = &user->ring[0];
> + else
> + cbdr = netc_select_cbdr(user);

AI: The special case for cbdr_num == 1 is redundant; netc_select_cbdr() handles
it correctly. Simplify to: cbdr = netc_select_cbdr(user);

Need owner do futher judgement

Frank