Re: [PATCH net-next] drivers/net/ethernet/micrel/ks8851_mll: Implement basic statistics

[Joe Perches <joe@perches.com>]

On Wed, 2013-01-23 at 18:46 +0000, Choi, David wrote:
> +++ net-next/drivers/net/ethernet/micrel/ks8851_mll.c	2013-01-23 10:31:24.000000000 -0800
> @@ -793,17 +793,35 @@ static void ks_rcv(struct ks_net *ks, st
>  	frame_hdr = ks->frame_head_info;
>  	while (ks->frame_cnt--) {
>  		skb = netdev_alloc_skb(netdev, frame_hdr->len + 16);
> -		if (likely(skb && (frame_hdr->sts & RXFSHR_RXFV) &&
> +		if (unlikely(!skb)) {
> +			/* discard the packet from the device */
> +			ks_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_RRXEF);
> +			netdev->stats.rx_dropped++;
> +		}
> +
> +		else if (likely((frame_hdr->sts & RXFSHR_RXFV) &&

Couple of trivial comments:

it' be nicer if the close brace and else
was on the same line

		} else if (likely(...

>  			(frame_hdr->len < RX_BUF_SIZE) && frame_hdr->len)) {
>  			skb_reserve(skb, 2);
>  			/* read data block including CRC 4 bytes */
>  			ks_read_qmu(ks, (u16 *)skb->data, frame_hdr->len);
> -			skb_put(skb, frame_hdr->len);
> +
> +			/* exclude the size of CRC */
> +			skb_put(skb, frame_hdr->len - 4);
>  			skb->protocol = eth_type_trans(skb, netdev);
>  			netif_rx(skb);
> +			netdev->stats.rx_packets++;
> +
> +			/* crc field */
> +			netdev->stats.rx_bytes += frame_hdr->len - 4;
>  		} else {
> -			pr_err("%s: err:skb alloc\n", __func__);
> -			ks_wrreg16(ks, KS_RXQCR, (ks->rc_rxqcr | RXQCR_RRXEF));
> +			/* discard the packet from the device */
> +			ks_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_RRXEF);
> +			netdev->stats.rx_dropped++;
> +			if (frame_hdr->len >= RX_BUF_SIZE || !frame_hdr->len)
> +				netdev->stats.rx_length_errors++;
> +			if (!(frame_hdr->sts & RXFSHR_RXFV))
> +				netdev->stats.rx_frame_errors++;
> +
>  			if (skb)
>  				dev_kfree_skb_irq(skb);

You don't need to test skb here anymore.