From: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
Date: Wed, 15 Feb 2023 15:33:09 +0100
> Xsk Tx can be triggered via either sendmsg() or poll() syscalls. These
> two paths share a call to common function xsk_xmit() which has two
> sanity checks within. A pseudo code example to show the two paths:
[...]
> @@ -627,17 +618,31 @@ static bool xsk_no_wakeup(struct sock *sk)
> #endif
> }
>
> +static int xsk_check_common(struct xdp_sock *xs)
> +{
> + if (unlikely(!xsk_is_bound(xs)))
> + return -ENXIO;
> + if (unlikely(!(xs->dev->flags & IFF_UP)))
> + return -ENETDOWN;
> +
> + return 0;
> +}
It's called several times in the code. Have you tried marking it inline
and compare the object code? I'm worrying a bit some beyond-smart
compiler can uninline these 4 lines and slow down things for no reason.
(it's okay to have inlines in C files if proven that not marking them
hurts a lot)
> +
> static int __xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len)
The rest is:
Reviewed-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
Thanks,
Olek
