Re: [PATCH 5/5] net: add skb.old_queue_mapping

[Eric Dumazet <eric.dumazet@gmail.com>]

Le lundi 13 décembre 2010 à 22:43 +0800, Changli Gao a écrit :
> For the skbs returned from ifb, we should use the queue_mapping
> saved before ifb.
> 
> We save old queue_mapping in old_queue_mapping just before calling 
> dev_queue_xmit, and restore the old_queue_mapping to queue_mapping
> just before reinjecting the skb.
> 
> dev_pick_tx() use the current queue_mapping for the skbs reinjected
> by ifb.
> 
> Signed-off-by: Changli Gao <xiaosuo@gmail.com>
> ---
>  drivers/net/ifb.c      |    1 +
>  include/linux/skbuff.h |    3 +++
>  net/core/dev.c         |    5 +++++
>  net/sched/act_mirred.c |    1 +
>  4 files changed, 10 insertions(+)
> diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
> index 16c767b..481e4b1 100644
> --- a/drivers/net/ifb.c
> +++ b/drivers/net/ifb.c
> @@ -95,6 +95,7 @@ static void ri_tasklet(unsigned long _dev)
>  		u64_stats_update_end(&qp->syncp);
>  		skb->skb_iif = dev->ifindex;
>  
> +		skb->queue_mapping = skb->old_queue_mapping;
>  		if (from & AT_EGRESS) {
>  			dev_queue_xmit(skb);
>  		} else if (from & AT_INGRESS) {
> diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
> index 19f37a6..2ce2a96 100644
> --- a/include/linux/skbuff.h
> +++ b/include/linux/skbuff.h
> @@ -403,6 +403,9 @@ struct sk_buff {
>  	};
>  
>  	__u16			vlan_tci;
> +#ifdef CONFIG_NET_CLS_ACT
> +	__u16			old_queue_mapping;
> +#endif
>  

Are you sure we need this field here ? Why not using cb[] for example ?


>  	sk_buff_data_t		transport_header;
>  	sk_buff_data_t		network_header;
> diff --git a/net/core/dev.c b/net/core/dev.c
> index d28b3a0..8e97cfd 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -2190,6 +2190,11 @@ static struct netdev_queue *dev_pick_tx(struct net_device *dev,
>  	int queue_index;
>  	const struct net_device_ops *ops = dev->netdev_ops;
>  
> +#ifdef CONFIG_NET_CLS_ACT
> +	if (skb->tc_verd & TC_NCLS)
> +		queue_index = skb_get_queue_mapping(skb);
> +	else
> +#endif
>  	if (dev->real_num_tx_queues == 1)
>  		queue_index = 0;
>  	else if (ops->ndo_select_queue) {
> diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
> index 0c311be..853eb30 100644
> --- a/net/sched/act_mirred.c
> +++ b/net/sched/act_mirred.c
> @@ -197,6 +197,7 @@ static int tcf_mirred(struct sk_buff *skb, struct tc_action *a,
>  
>  	skb2->skb_iif = skb->dev->ifindex;
>  	skb2->dev = dev;
> +	skb2->old_queue_mapping = skb->queue_mapping;
>  	dev_queue_xmit(skb2);
>  	err = 0;
>