From: Eric Garver <e@erig.me>
To: davem@davemloft.net
Cc: netdev@vger.kernel.org
Subject: [PATCH net] udp: inuse checks can quit early for reuseport
Date: Thu, 5 Jan 2017 20:22:36 -0500 [thread overview]
Message-ID: <20170106012236.20078-1-e@erig.me> (raw)
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 <e@erig.me>
---
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 1307a7c2e544..4318d72e0248 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 {
--
2.10.0
next reply other threads:[~2017-01-06 1:32 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-06 1:22 Eric Garver [this message]
2017-01-07 1:57 ` [PATCH net] udp: inuse checks can quit early for reuseport David Miller
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