Commit 7da517a3 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller
Browse files

net: core: Another step of skb receive list processing 



netif_receive_skb_list_internal() now processes a list and hands it
 on to the next function.

Signed-off-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 920572b7

net/core/dev.c

+56 −5
Original line number Diff line number Diff line
@@ -4843,6 +4843,14 @@ static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 
	return ret;

}



static void __netif_receive_skb_list(struct list_head *head)

{

	struct sk_buff *skb, *next;



	list_for_each_entry_safe(skb, next, head, list)

		__netif_receive_skb(skb);

}



static int netif_receive_skb_internal(struct sk_buff *skb)

{

	int ret;
@@ -4883,6 +4891,50 @@ static int netif_receive_skb_internal(struct sk_buff *skb) 
	return ret;

}



static void netif_receive_skb_list_internal(struct list_head *head)

{

	struct bpf_prog *xdp_prog = NULL;

	struct sk_buff *skb, *next;



	list_for_each_entry_safe(skb, next, head, list) {

		net_timestamp_check(netdev_tstamp_prequeue, skb);

		if (skb_defer_rx_timestamp(skb))

			/* Handled, remove from list */

			list_del(&skb->list);

	}



	if (static_branch_unlikely(&generic_xdp_needed_key)) {

		preempt_disable();

		rcu_read_lock();

		list_for_each_entry_safe(skb, next, head, list) {

			xdp_prog = rcu_dereference(skb->dev->xdp_prog);

			if (do_xdp_generic(xdp_prog, skb) != XDP_PASS)

				/* Dropped, remove from list */

				list_del(&skb->list);

		}

		rcu_read_unlock();

		preempt_enable();

	}



	rcu_read_lock();

#ifdef CONFIG_RPS

	if (static_key_false(&rps_needed)) {

		list_for_each_entry_safe(skb, next, head, list) {

			struct rps_dev_flow voidflow, *rflow = &voidflow;

			int cpu = get_rps_cpu(skb->dev, skb, &rflow);



			if (cpu >= 0) {

				enqueue_to_backlog(skb, cpu, &rflow->last_qtail);

				/* Handled, remove from list */

				list_del(&skb->list);

			}

		}

	}

#endif

	__netif_receive_skb_list(head);

	rcu_read_unlock();

}



/**

 *	netif_receive_skb - process receive buffer from network

 *	@skb: buffer to process
@@ -4910,20 +4962,19 @@ EXPORT_SYMBOL(netif_receive_skb); 
 *	netif_receive_skb_list - process many receive buffers from network

 *	@head: list of skbs to process.

 *

 *	For now, just calls netif_receive_skb() in a loop, ignoring the

 *	return value.

 *	Since return value of netif_receive_skb() is normally ignored, and

 *	wouldn't be meaningful for a list, this function returns void.

 *

 *	This function may only be called from softirq context and interrupts

 *	should be enabled.

 */

void netif_receive_skb_list(struct list_head *head)

{

	struct sk_buff *skb, *next;

	struct sk_buff *skb;



	list_for_each_entry(skb, head, list)

		trace_netif_receive_skb_list_entry(skb);

	list_for_each_entry_safe(skb, next, head, list)

		netif_receive_skb_internal(skb);

	netif_receive_skb_list_internal(head);

}

EXPORT_SYMBOL(netif_receive_skb_list);