summaryrefslogtreecommitdiff
path: root/net/ipv6/udp.c
diff options
context:
space:
mode:
authorEric Dumazet <eric.dumazet@gmail.com>2010-04-28 14:35:48 -0700
committerDavid S. Miller <davem@davemloft.net>2010-04-28 14:35:48 -0700
commit4b0b72f7dd617b13abd1b04c947e15873e011a24 (patch)
tree16fc7bc990fa47cccb62bdb34cb23bd3c26b7a50 /net/ipv6/udp.c
parentcfc1fbb079b265bf69d4ceba590a2e2c1a1cde33 (diff)
net: speedup udp receive path
Since commit 95766fff ([UDP]: Add memory accounting.), each received packet needs one extra sock_lock()/sock_release() pair. This added latency because of possible backlog handling. Then later, ticket spinlocks added yet another latency source in case of DDOS. This patch introduces lock_sock_bh() and unlock_sock_bh() synchronization primitives, avoiding one atomic operation and backlog processing. skb_free_datagram_locked() uses them instead of full blown lock_sock()/release_sock(). skb is orphaned inside locked section for proper socket memory reclaim, and finally freed outside of it. UDP receive path now take the socket spinlock only once. 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.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 3ead20ad9d07..91c60f0090a4 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -424,7 +424,7 @@ out:
return err;
csum_copy_err:
- lock_sock(sk);
+ lock_sock_bh(sk);
if (!skb_kill_datagram(sk, skb, flags)) {
if (is_udp4)
UDP_INC_STATS_USER(sock_net(sk),
@@ -433,7 +433,7 @@ csum_copy_err:
UDP6_INC_STATS_USER(sock_net(sk),
UDP_MIB_INERRORS, is_udplite);
}
- release_sock(sk);
+ unlock_sock_bh(sk);
if (flags & MSG_DONTWAIT)
return -EAGAIN;