Re: [PATCH net] tun: add missing rx stats accounting in tun_xdp_act

[Denis Kirjanov]

On 1/16/24 12:36, Yunjian Wang wrote:
> There are few places on the receive path where packet receives and packet
> drops were not accounted for. This patch fixes that issue.
You've missed a "Fixes" tag
> 
> Signed-off-by: Yunjian Wang <wangyunjian@xxxxxxxxxx>
> ---
>  drivers/net/tun.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index afa5497f7c35..232e5319ac77 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -1626,17 +1626,14 @@ static int tun_xdp_act(struct tun_struct *tun, struct bpf_prog *xdp_prog,
>  		       struct xdp_buff *xdp, u32 act)
>  {
>  	int err;
> +	unsigned int datasize = xdp->data_end - xdp->data;
>  
>  	switch (act) {
>  	case XDP_REDIRECT:
>  		err = xdp_do_redirect(tun->dev, xdp, xdp_prog);
> -		if (err)
> -			return err;
>  		break;
>  	case XDP_TX:
>  		err = tun_xdp_tx(tun->dev, xdp);
> -		if (err < 0)
> -			return err;
>  		break;
>  	case XDP_PASS:
>  		break;
> @@ -1651,6 +1648,13 @@ static int tun_xdp_act(struct tun_struct *tun, struct bpf_prog *xdp_prog,
>  		break;
>  	}
>  
> +	if (err < 0) {
> +		act = err;
> +		dev_core_stats_rx_dropped_inc(tun->dev);
> +	} else if (act == XDP_REDIRECT || act == XDP_TX) {
> +		dev_sw_netstats_rx_add(tun->dev, datasize);
> +	}
> +
>  	return act;
>  }
>