From 079096f103faca2dd87342cca6f23d4b34da8871 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 2 Oct 2015 11:43:32 -0700 Subject: tcp/dccp: install syn_recv requests into ehash table In this patch, we insert request sockets into TCP/DCCP regular ehash table (where ESTABLISHED and TIMEWAIT sockets are) instead of using the per listener hash table. ACK packets find SYN_RECV pseudo sockets without having to find and lock the listener. In nominal conditions, this halves pressure on listener lock. Note that this will allow for SO_REUSEPORT refinements, so that we can select a listener using cpu/numa affinities instead of the prior 'consistent hash', since only SYN packets will apply this selection logic. We will shrink listen_sock in the following patch to ease code review. Signed-off-by: Eric Dumazet Cc: Ying Cai Cc: Willem de Bruijn Signed-off-by: David S. Miller --- net/ipv6/inet6_connection_sock.c | 67 -------------------------------- net/ipv6/tcp_ipv6.c | 82 ++++++++++++++++++---------------------- 2 files changed, 36 insertions(+), 113 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c index ea915aa5e4e2..5d1c7cee2cb2 100644 --- a/net/ipv6/inet6_connection_sock.c +++ b/net/ipv6/inet6_connection_sock.c @@ -94,73 +94,6 @@ struct dst_entry *inet6_csk_route_req(const struct sock *sk, } EXPORT_SYMBOL(inet6_csk_route_req); -/* - * request_sock (formerly open request) hash tables. - */ -static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport, - const u32 rnd, const u32 synq_hsize) -{ - u32 c; - - c = jhash_3words((__force u32)raddr->s6_addr32[0], - (__force u32)raddr->s6_addr32[1], - (__force u32)raddr->s6_addr32[2], - rnd); - - c = jhash_2words((__force u32)raddr->s6_addr32[3], - (__force u32)rport, - c); - - return c & (synq_hsize - 1); -} - -struct request_sock *inet6_csk_search_req(struct sock *sk, - const __be16 rport, - const struct in6_addr *raddr, - const struct in6_addr *laddr, - const int iif) -{ - struct inet_connection_sock *icsk = inet_csk(sk); - struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; - struct request_sock *req; - u32 hash = inet6_synq_hash(raddr, rport, lopt->hash_rnd, - lopt->nr_table_entries); - - spin_lock(&icsk->icsk_accept_queue.syn_wait_lock); - for (req = lopt->syn_table[hash]; req != NULL; req = req->dl_next) { - const struct inet_request_sock *ireq = inet_rsk(req); - - if (ireq->ir_rmt_port == rport && - req->rsk_ops->family == AF_INET6 && - ipv6_addr_equal(&ireq->ir_v6_rmt_addr, raddr) && - ipv6_addr_equal(&ireq->ir_v6_loc_addr, laddr) && - (!ireq->ir_iif || ireq->ir_iif == iif)) { - atomic_inc(&req->rsk_refcnt); - WARN_ON(req->sk != NULL); - break; - } - } - spin_unlock(&icsk->icsk_accept_queue.syn_wait_lock); - - return req; -} -EXPORT_SYMBOL_GPL(inet6_csk_search_req); - -void inet6_csk_reqsk_queue_hash_add(struct sock *sk, - struct request_sock *req, - const unsigned long timeout) -{ - struct inet_connection_sock *icsk = inet_csk(sk); - struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; - const u32 h = inet6_synq_hash(&inet_rsk(req)->ir_v6_rmt_addr, - inet_rsk(req)->ir_rmt_port, - lopt->hash_rnd, lopt->nr_table_entries); - - reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); - inet_csk_reqsk_queue_added(sk); -} -EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add); - void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index cadb44a2d34e..a215614cfb2b 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -727,7 +727,6 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { .route_req = tcp_v6_route_req, .init_seq = tcp_v6_init_sequence, .send_synack = tcp_v6_send_synack, - .queue_hash_add = inet6_csk_reqsk_queue_hash_add, }; static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, @@ -938,37 +937,11 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, } -static struct sock *tcp_v6_hnd_req(struct sock *sk, struct sk_buff *skb) +static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) { +#ifdef CONFIG_SYN_COOKIES const struct tcphdr *th = tcp_hdr(skb); - struct request_sock *req; - struct sock *nsk; - - /* Find possible connection requests. */ - req = inet6_csk_search_req(sk, th->source, - &ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, tcp_v6_iif(skb)); - if (req) { - nsk = tcp_check_req(sk, skb, req, false); - if (!nsk || nsk == sk) - reqsk_put(req); - return nsk; - } - nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo, - &ipv6_hdr(skb)->saddr, th->source, - &ipv6_hdr(skb)->daddr, ntohs(th->dest), - tcp_v6_iif(skb)); - - if (nsk) { - if (nsk->sk_state != TCP_TIME_WAIT) { - bh_lock_sock(nsk); - return nsk; - } - inet_twsk_put(inet_twsk(nsk)); - return NULL; - } -#ifdef CONFIG_SYN_COOKIES if (!th->syn) sk = cookie_v6_check(sk, skb); #endif @@ -1258,15 +1231,11 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) goto csum_err; if (sk->sk_state == TCP_LISTEN) { - struct sock *nsk = tcp_v6_hnd_req(sk, skb); + struct sock *nsk = tcp_v6_cookie_check(sk, skb); + if (!nsk) goto discard; - /* - * Queue it on the new socket if the new socket is active, - * otherwise we just shortcircuit this and continue with - * the new socket.. - */ if (nsk != sk) { sock_rps_save_rxhash(nsk, skb); sk_mark_napi_id(nsk, skb); @@ -1402,6 +1371,33 @@ process: if (sk->sk_state == TCP_TIME_WAIT) goto do_time_wait; + if (sk->sk_state == TCP_NEW_SYN_RECV) { + struct request_sock *req = inet_reqsk(sk); + struct sock *nsk = NULL; + + sk = req->rsk_listener; + tcp_v6_fill_cb(skb, hdr, th); + if (tcp_v6_inbound_md5_hash(sk, skb)) { + reqsk_put(req); + goto discard_it; + } + if (sk->sk_state == TCP_LISTEN) + nsk = tcp_check_req(sk, skb, req, false); + if (!nsk) { + reqsk_put(req); + goto discard_it; + } + if (nsk == sk) { + sock_hold(sk); + reqsk_put(req); + tcp_v6_restore_cb(skb); + } else if (tcp_child_process(sk, nsk, skb)) { + tcp_v6_send_reset(nsk, skb); + goto discard_it; + } else { + return 0; + } + } if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); goto discard_and_relse; @@ -1765,18 +1761,12 @@ static int tcp6_seq_show(struct seq_file *seq, void *v) } st = seq->private; - switch (st->state) { - case TCP_SEQ_STATE_LISTENING: - case TCP_SEQ_STATE_ESTABLISHED: - if (sk->sk_state == TCP_TIME_WAIT) - get_timewait6_sock(seq, v, st->num); - else - get_tcp6_sock(seq, v, st->num); - break; - case TCP_SEQ_STATE_OPENREQ: + if (sk->sk_state == TCP_TIME_WAIT) + get_timewait6_sock(seq, v, st->num); + else if (sk->sk_state == TCP_NEW_SYN_RECV) get_openreq6(seq, v, st->num); - break; - } + else + get_tcp6_sock(seq, v, st->num); out: return 0; } -- cgit v1.2.3