Re: [PATCH 2/2] rps: changes to bnx2x to get device hash

[Stephen Hemminger <shemminger@vyatta.com>]

On Tue, 10 Nov 2009 22:53:36 -0800
Tom Herbert <therbert@google.com> wrote:

> +
> +			if (get_hdrhash && (cqe_fp_status_flags &
> +			    ETH_FAST_PATH_RX_CQE_RSS_HASH_FLG)) {
> +				u8 hash_type = cqe_fp_status_flags &
> +					ETH_FAST_PATH_RX_CQE_RSS_HASH_TYPE;
> +
> +				skb->rxhash = le32_to_cpu(
> +				      cqe->fast_path_cqe.rss_hash_result);
> +				if (!skb->rxhash)
> +					skb->rxhash = 1;
> +
> +				/* unicast IPv4 packet? */
> +				if (((hash_type == IPV4_HASH_TYPE) ||
> +				     (hash_type == TCP_IPV4_HASH_TYPE)) &&
> +				    (cqe_fp_pars_flags &
> +					PARSING_FLAGS_ETHERNET_ADDRESS_TYPE)) {
> +					skb->dev = bp->dev;
> +					skb_reset_mac_header(skb);
> +					skb_pull(skb, ETH_HLEN);
> +					skb->protocol =
> +					    __constant_htons(ETH_P_IP);
> +				} else
> +					skb->protocol =
> +					    eth_type_trans(skb, bp->dev);
> +			} else
> +				skb->protocol = eth_type_trans(skb, bp->dev);

How about putting this all in an inline function:

static inline u16 bn2x_get_type(...) {
}


	skb->protocol = bn2x_get_type(...);

Then you won't have two calls to eth_type_trans,

Also: __constant_htons() should not be used directly (except switch statements),
macro for htons() does it automatically if argument is constant.