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| author |   Eric Dumazet <eric.dumazet@gmail.com> | 2010-05-11 23:19:48 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2010-05-17 17:18:50 -0700 |
| commit | 7fee226ad2397b635e2fd565a59ca3ae08a164cd (patch) | |
| tree | 0bcd26150ad74ec1a237109de87a3d214a07fc22 /net/ipv4/netfilter.c | |
| parent | rps: avoid one atomic in enqueue_to_backlog (diff) | |
| download | linux-dev-7fee226ad2397b635e2fd565a59ca3ae08a164cd.tar.xz linux-dev-7fee226ad2397b635e2fd565a59ca3ae08a164cd.zip | |
net: add a noref bit on skb dst
Use low order bit of skb->_skb_dst to tell dst is not refcounted.
Change _skb_dst to _skb_refdst to make sure all uses are catched.
skb_dst() returns the dst, regardless of noref bit set or not, but
with a lockdep check to make sure a noref dst is not given if current
user is not rcu protected.
New skb_dst_set_noref() helper to set an notrefcounted dst on a skb.
(with lockdep check)
skb_dst_drop() drops a reference only if skb dst was refcounted.
skb_dst_force() helper is used to force a refcount on dst, when skb
is queued and not anymore RCU protected.
Use skb_dst_force() in __sk_add_backlog(), __dev_xmit_skb() if
!IFF_XMIT_DST_RELEASE or skb enqueued on qdisc queue, in
sock_queue_rcv_skb(), in __nf_queue().
Use skb_dst_force() in dev_requeue_skb().
Note: dst_use_noref() still dirties dst, we might transform it
later to do one dirtying per jiffies.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/netfilter.c')
| -rw-r--r-- | net/ipv4/netfilter.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c index 82fb43c5c59e..07de855e2175 100644 --- a/net/ipv4/netfilter.c +++ b/net/ipv4/netfilter.c @@ -17,7 +17,7 @@ int ip_route_me_harder(struct sk_buff *skb, unsigned addr_type) const struct iphdr *iph = ip_hdr(skb); struct rtable *rt; struct flowi fl = {}; - struct dst_entry *odst; + unsigned long orefdst; unsigned int hh_len; unsigned int type; @@ -51,14 +51,14 @@ int ip_route_me_harder(struct sk_buff *skb, unsigned addr_type) if (ip_route_output_key(net, &rt, &fl) != 0) return -1; - odst = skb_dst(skb); + orefdst = skb->_skb_refdst; if (ip_route_input(skb, iph->daddr, iph->saddr, RT_TOS(iph->tos), rt->u.dst.dev) != 0) { dst_release(&rt->u.dst); return -1; } dst_release(&rt->u.dst); - dst_release(odst); + refdst_drop(orefdst); } if (skb_dst(skb)->error) |