From df560056d960a3e164c179d89770d5a51b798537 Mon Sep 17 00:00:00 2001 From: Eric Garver Date: Thu, 5 Jan 2017 20:22:36 -0500 Subject: [PATCH] udp: inuse checks can quit early for reuseport UDP lib inuse checks will walk the entire hash bucket to check if the portaddr is in use. In the case of reuseport we can stop searching when we find a matching reuseport. On a 16-core VM a test program that spawns 16 threads that each bind to 1024 sockets (one per 10ms) takes 1m45s. With this change it takes 11s. Also add a cond_resched() when the port is not specified. Signed-off-by: Eric Garver Signed-off-by: David S. Miller --- net/ipv4/udp.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 1307a7c..4318d72 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -153,13 +153,18 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num, (!sk2->sk_reuse || !sk->sk_reuse) && (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && - (!sk2->sk_reuseport || !sk->sk_reuseport || - rcu_access_pointer(sk->sk_reuseport_cb) || - !uid_eq(uid, sock_i_uid(sk2))) && saddr_comp(sk, sk2, true)) { - if (!bitmap) - return 1; - __set_bit(udp_sk(sk2)->udp_port_hash >> log, bitmap); + if (sk2->sk_reuseport && sk->sk_reuseport && + !rcu_access_pointer(sk->sk_reuseport_cb) && + uid_eq(uid, sock_i_uid(sk2))) { + if (!bitmap) + return 0; + } else { + if (!bitmap) + return 1; + __set_bit(udp_sk(sk2)->udp_port_hash >> log, + bitmap); + } } } return 0; @@ -188,11 +193,14 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num, (!sk2->sk_reuse || !sk->sk_reuse) && (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && - (!sk2->sk_reuseport || !sk->sk_reuseport || - rcu_access_pointer(sk->sk_reuseport_cb) || - !uid_eq(uid, sock_i_uid(sk2))) && saddr_comp(sk, sk2, true)) { - res = 1; + if (sk2->sk_reuseport && sk->sk_reuseport && + !rcu_access_pointer(sk->sk_reuseport_cb) && + uid_eq(uid, sock_i_uid(sk2))) { + res = 0; + } else { + res = 1; + } break; } } @@ -285,6 +293,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum, snum += rand; } while (snum != first); spin_unlock_bh(&hslot->lock); + cond_resched(); } while (++first != last); goto fail; } else { -- 2.7.4