From 3895db62d5e9f829e55c9298baf4e870be3b2fe0 Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Tue, 24 Apr 2018 23:07:45 +0800 Subject: [PATCH] Revert "net: init sk_cookie for inet socket" This reverts commit ("net: init sk_cookie for inet socket") Per discussion with Eric, when update sock_net(sk)->cookie_gen, the whole cache cache line will be invalidated, as this cache line is shared with all cpus, that may cause great performace hit. Bellow is the data form Eric. "Performance is reduced from ~5 Mpps to ~3.8 Mpps with 16 RX queues on my host" when running synflood test. Have to revert it to prevent from cache line false sharing. Signed-off-by: Yafang Shao Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/sock_diag.h | 9 --------- net/ipv4/tcp_input.c | 8 +------- 2 files changed, 1 insertion(+), 16 deletions(-) diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h index 5c916e6dff362..15fe980a27ead 100644 --- a/include/linux/sock_diag.h +++ b/include/linux/sock_diag.h @@ -25,15 +25,6 @@ void sock_diag_unregister(const struct sock_diag_handler *h); void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); -static inline -void sock_init_cookie(struct sock *sk) -{ - u64 res; - - res = atomic64_inc_return(&sock_net(sk)->cookie_gen); - atomic64_set(&sk->sk_cookie, res); -} - u64 sock_gen_cookie(struct sock *sk); int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie); void sock_diag_save_cookie(struct sock *sk, __u32 *cookie); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 17b78582ba631..5a17cfc753260 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -78,7 +78,6 @@ #include #include #include -#include int sysctl_tcp_max_orphans __read_mostly = NR_FILE; @@ -6191,15 +6190,10 @@ struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, #if IS_ENABLED(CONFIG_IPV6) ireq->pktopts = NULL; #endif + atomic64_set(&ireq->ir_cookie, 0); ireq->ireq_state = TCP_NEW_SYN_RECV; write_pnet(&ireq->ireq_net, sock_net(sk_listener)); ireq->ireq_family = sk_listener->sk_family; - - BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) != - offsetof(struct sock, sk_cookie)); - BUILD_BUG_ON(offsetof(struct inet_request_sock, ireq_net) != - offsetof(struct sock, sk_net)); - sock_init_cookie((struct sock *)ireq); } return req; -- 2.39.5