Commit ba55ef81 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: add (struct uncached_list)->quarantine list 



This is an optimization to keep the per-cpu lists as short as possible:

Whenever rt6_uncached_list_flush_dev() changes one rt6_info
matching the disappearing device, it can can transfer the object
to a quarantine list, waiting for a final rt6_uncached_list_del().

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e5f80fcf

net/ipv6/route.c

+14 −3
Original line number Diff line number Diff line
@@ -130,6 +130,7 @@ static struct fib6_info *rt6_get_route_info(struct net *net, 
struct uncached_list {

	spinlock_t		lock;

	struct list_head	head;

	struct list_head	quarantine;

};



static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
@@ -151,7 +152,7 @@ void rt6_uncached_list_del(struct rt6_info *rt) 
		struct uncached_list *ul = rt->rt6i_uncached_list;



		spin_lock_bh(&ul->lock);

		list_del(&rt->rt6i_uncached);

		list_del_init(&rt->rt6i_uncached);

		spin_unlock_bh(&ul->lock);

	}

}
@@ -162,16 +163,21 @@ static void rt6_uncached_list_flush_dev(struct net_device *dev) 


	for_each_possible_cpu(cpu) {

		struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);

		struct rt6_info *rt;

		struct rt6_info *rt, *safe;



		if (list_empty(&ul->head))

			continue;



		spin_lock_bh(&ul->lock);

		list_for_each_entry(rt, &ul->head, rt6i_uncached) {

		list_for_each_entry_safe(rt, safe, &ul->head, rt6i_uncached) {

			struct inet6_dev *rt_idev = rt->rt6i_idev;

			struct net_device *rt_dev = rt->dst.dev;

			bool handled = false;



			if (rt_idev->dev == dev) {

				rt->rt6i_idev = in6_dev_get(blackhole_netdev);

				in6_dev_put(rt_idev);

				handled = true;

			}



			if (rt_dev == dev) {
@@ -179,7 +185,11 @@ static void rt6_uncached_list_flush_dev(struct net_device *dev) 
				dev_replace_track(rt_dev, blackhole_netdev,

						  &rt->dst.dev_tracker,

						  GFP_ATOMIC);

				handled = true;

			}

			if (handled)

				list_move(&rt->rt6i_uncached,

					  &ul->quarantine);

		}

		spin_unlock_bh(&ul->lock);

	}
@@ -6727,6 +6737,7 @@ int __init ip6_route_init(void) 
		struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);



		INIT_LIST_HEAD(&ul->head);

		INIT_LIST_HEAD(&ul->quarantine);

		spin_lock_init(&ul->lock);

	}