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/core/sock.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/core/sock.c')
-rw-r--r-- | net/core/sock.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index 58ebd146ce5a..51041759517e 100644 --- a/net/core/sock.c +++ b/net/core/sock.c | |||
@@ -327,6 +327,10 @@ int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) | |||
327 | 327 | ||
328 | skb->dev = NULL; | 328 | skb->dev = NULL; |
329 | 329 | ||
330 | if (sk_rcvqueues_full(sk, skb)) { | ||
331 | atomic_inc(&sk->sk_drops); | ||
332 | goto discard_and_relse; | ||
333 | } | ||
330 | if (nested) | 334 | if (nested) |
331 | bh_lock_sock_nested(sk); | 335 | bh_lock_sock_nested(sk); |
332 | else | 336 | else |
@@ -1885,7 +1889,6 @@ void sock_init_data(struct socket *sock, struct sock *sk) | |||
1885 | sk->sk_allocation = GFP_KERNEL; | 1889 | sk->sk_allocation = GFP_KERNEL; |
1886 | sk->sk_rcvbuf = sysctl_rmem_default; | 1890 | sk->sk_rcvbuf = sysctl_rmem_default; |
1887 | sk->sk_sndbuf = sysctl_wmem_default; | 1891 | sk->sk_sndbuf = sysctl_wmem_default; |
1888 | sk->sk_backlog.limit = sk->sk_rcvbuf << 1; | ||
1889 | sk->sk_state = TCP_CLOSE; | 1892 | sk->sk_state = TCP_CLOSE; |
1890 | sk_set_socket(sk, sock); | 1893 | sk_set_socket(sk, sock); |
1891 | 1894 | ||