path: root/net/ipv4/inet_diag.c
diff options
authorEric Dumazet <edumazet@google.com>2016-04-01 08:52:17 -0700
committerDavid S. Miller <davem@davemloft.net>2016-04-04 22:11:20 -0400
commit3b24d854cb35383c30642116e5992fd619bdc9bc (patch)
treea2a0c8c8ad3f7f974d6a9b11b17865edfb62d6d1 /net/ipv4/inet_diag.c
parentinet: reqsk_alloc() needs to take care of dead listeners (diff)
tcp/dccp: do not touch listener sk_refcnt under synflood
When a SYNFLOOD targets a non SO_REUSEPORT listener, multiple cpus contend on sk->sk_refcnt and sk->sk_wmem_alloc changes. By letting listeners use SOCK_RCU_FREE infrastructure, we can relax TCP_LISTEN lookup rules and avoid touching sk_refcnt Note that we still use SLAB_DESTROY_BY_RCU rules for other sockets, only listeners are impacted by this change. Peak performance under SYNFLOOD is increased by ~33% : On my test machine, I could process 3.2 Mpps instead of 2.4 Mpps Most consuming functions are now skb_set_owner_w() and sock_wfree() contending on sk->sk_wmem_alloc when cooking SYNACK and freeing them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/inet_diag.c')
1 files changed, 1 insertions, 2 deletions
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index ea8df527b279..bd591eb81ec9 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -775,13 +775,12 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
struct inet_listen_hashbucket *ilb;
- struct hlist_nulls_node *node;
struct sock *sk;
num = 0;
ilb = &hashinfo->listening_hash[i];
- sk_nulls_for_each(sk, node, &ilb->head) {
+ sk_for_each(sk, &ilb->head) {
struct inet_sock *inet = inet_sk(sk);
if (!net_eq(sock_net(sk), net))