Subject: Re: [RFC net-next v3 09/10] net: bridge: mrp: Integrate MRP into the bridge

From: Andrew Lunn <[email-masked]>
Date: Sat, 25 Jan 2020 17:16:15 +0100

>  br_netif_receive_skb(struct net *net, struct sock *sk, struct sk_buff *skb)
> @@ -338,6 +341,17 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
>  			return RX_HANDLER_CONSUMED;
>  		}
>  	}
> +#ifdef CONFIG_BRIDGE_MRP
> +	/* If there is no MRP instance do normal forwarding */
> +	if (!p->mrp_aware)
> +		goto forward;
> +
> +	if (skb->protocol == htons(ETH_P_MRP))
> +		return RX_HANDLER_PASS;

What MAC address is used for these MRP frames? It would make sense to
use a L2 link local destination address, since i assume they are not
supposed to be forwarded by the bridge. If so, you could extend the
if (unlikely(is_link_local_ether_addr(dest))) condition.

> +
> +	if (p->state == BR_STATE_BLOCKING)
> +		goto drop;
> +#endif

Is this needed? The next block of code is a switch statement on
p->state. The default case, which BR_STATE_BLOCKING should hit, is
drop.

This function is on the hot path. So we should try to optimize it as
much as possible.

     Andrew