summaryrefslogtreecommitdiffstats
path: root/net/core
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/core
parentcfc1fbb079b265bf69d4ceba590a2e2c1a1cde33 (diff)
downloadop-kernel-dev-4b0b72f7dd617b13abd1b04c947e15873e011a24.zip
op-kernel-dev-4b0b72f7dd617b13abd1b04c947e15873e011a24.tar.gz
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/core')
-rw-r--r--net/core/datagram.c10
1 files changed, 7 insertions, 3 deletions
diff --git a/net/core/datagram.c b/net/core/datagram.c
index 5574a5dd..95b851f 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -229,9 +229,13 @@ EXPORT_SYMBOL(skb_free_datagram);
void skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb)
{
- lock_sock(sk);
- skb_free_datagram(sk, skb);
- release_sock(sk);
+ lock_sock_bh(sk);
+ skb_orphan(skb);
+ sk_mem_reclaim_partial(sk);
+ unlock_sock_bh(sk);
+
+ /* skb is now orphaned, might be freed outside of locked section */
+ consume_skb(skb);
}
EXPORT_SYMBOL(skb_free_datagram_locked);
OpenPOWER on IntegriCloud