diff options
author | Eric Dumazet <eric.dumazet@gmail.com> | 2010-04-27 18:13:20 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-04-27 18:13:20 -0400 |
commit | c377411f2494a931ff7facdbb3a6839b1266bcf6 (patch) | |
tree | 6846cdcec913f50839e3916856f78f7e059ff5fb /net/ipv6/udp.c | |
parent | 6e7676c1a76aed6e957611d8d7a9e5592e23aeba (diff) |
net: sk_add_backlog() take rmem_alloc into account
Current socket backlog limit is not enough to really stop DDOS attacks,
because user thread spend many time to process a full backlog each
round, and user might crazy spin on socket lock.
We should add backlog size and receive_queue size (aka rmem_alloc) to
pace writers, and let user run without being slow down too much.
Introduce a sk_rcvqueues_full() helper, to avoid taking socket lock in
stress situations.
Under huge stress from a multiqueue/RPS enabled NIC, a single flow udp
receiver can now process ~200.000 pps (instead of ~100 pps before the
patch) on a 8 core machine.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/udp.c')
-rw-r--r-- | net/ipv6/udp.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 2850e35cee3d..3ead20ad9d07 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c | |||
@@ -584,6 +584,10 @@ static void flush_stack(struct sock **stack, unsigned int count, | |||
584 | 584 | ||
585 | sk = stack[i]; | 585 | sk = stack[i]; |
586 | if (skb1) { | 586 | if (skb1) { |
587 | if (sk_rcvqueues_full(sk, skb)) { | ||
588 | kfree_skb(skb1); | ||
589 | goto drop; | ||
590 | } | ||
587 | bh_lock_sock(sk); | 591 | bh_lock_sock(sk); |
588 | if (!sock_owned_by_user(sk)) | 592 | if (!sock_owned_by_user(sk)) |
589 | udpv6_queue_rcv_skb(sk, skb1); | 593 | udpv6_queue_rcv_skb(sk, skb1); |
@@ -759,6 +763,10 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, | |||
759 | 763 | ||
760 | /* deliver */ | 764 | /* deliver */ |
761 | 765 | ||
766 | if (sk_rcvqueues_full(sk, skb)) { | ||
767 | sock_put(sk); | ||
768 | goto discard; | ||
769 | } | ||
762 | bh_lock_sock(sk); | 770 | bh_lock_sock(sk); |
763 | if (!sock_owned_by_user(sk)) | 771 | if (!sock_owned_by_user(sk)) |
764 | udpv6_queue_rcv_skb(sk, skb); | 772 | udpv6_queue_rcv_skb(sk, skb); |