From owner-svn-src-all@freebsd.org Wed Feb 20 17:56:40 2019 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 15DC114FADC5; Wed, 20 Feb 2019 17:56:40 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AA35C8B555; Wed, 20 Feb 2019 17:56:39 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 9EDD18EDC; Wed, 20 Feb 2019 17:56:39 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x1KHud6l072524; Wed, 20 Feb 2019 17:56:39 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x1KHucYj072518; Wed, 20 Feb 2019 17:56:38 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201902201756.x1KHucYj072518@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Wed, 20 Feb 2019 17:56:38 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r344367 - in head/sys/netinet: . tcp_stacks X-SVN-Group: head X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: in head/sys/netinet: . tcp_stacks X-SVN-Commit-Revision: 344367 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: AA35C8B555 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.98 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; NEURAL_HAM_SHORT(-0.98)[-0.977,0]; NEURAL_HAM_LONG(-1.00)[-0.999,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Feb 2019 17:56:40 -0000 Author: tuexen Date: Wed Feb 20 17:56:38 2019 New Revision: 344367 URL: https://svnweb.freebsd.org/changeset/base/344367 Log: Use exponential backoff for retransmitting SYN segments as specified in the TCP RFCs. Reviewed by: rrs@, Richard Scheffenegger Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D18974 Modified: head/sys/netinet/tcp_stacks/rack.c head/sys/netinet/tcp_syncache.c head/sys/netinet/tcp_timer.c head/sys/netinet/tcp_timer.h Modified: head/sys/netinet/tcp_stacks/rack.c ============================================================================== --- head/sys/netinet/tcp_stacks/rack.c Wed Feb 20 17:10:30 2019 (r344366) +++ head/sys/netinet/tcp_stacks/rack.c Wed Feb 20 17:56:38 2019 (r344367) @@ -2869,7 +2869,7 @@ rack_timeout_rxt(struct tcpcb *tp, struct tcp_rack *ra TCPSTAT_INC(tcps_rexmttimeo); if ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) - rexmt = MSEC_2_TICKS(RACK_INITIAL_RTO * tcp_syn_backoff[tp->t_rxtshift]); + rexmt = MSEC_2_TICKS(RACK_INITIAL_RTO * tcp_backoff[tp->t_rxtshift]); else rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; TCPT_RANGESET(tp->t_rxtcur, rexmt, Modified: head/sys/netinet/tcp_syncache.c ============================================================================== --- head/sys/netinet/tcp_syncache.c Wed Feb 20 17:10:30 2019 (r344366) +++ head/sys/netinet/tcp_syncache.c Wed Feb 20 17:56:38 2019 (r344367) @@ -155,11 +155,11 @@ static int syncookie_cmp(struct in_conninfo *inc, str /* * Transmit the SYN,ACK fewer times than TCP_MAXRXTSHIFT specifies. * 3 retransmits corresponds to a timeout with default values of - * TCPTV_RTOBASE * ( 1 + - * tcp_syn_backoff[1] + - * tcp_syn_backoff[2] + - * tcp_syn_backoff[3]) + 3 * tcp_rexmit_slop, - * 3000 ms * (1 + 1 + 1 + 1) + 3 * 200 ms = 12600 ms, + * TCPTV_RTOBASE * ( 1 + + * tcp_backoff[1] + + * tcp_backoff[2] + + * tcp_backoff[3]) + 3 * tcp_rexmit_slop, + * 3000 ms * (1 + 2 + 4 + 8) + 3 * 200 ms = 45600 ms, * the odds are that the user has given up attempting to connect by then. */ #define SYNCACHE_MAXREXMTS 3 @@ -426,7 +426,7 @@ syncache_timeout(struct syncache *sc, struct syncache_ if (sc->sc_rxmits == 0) rexmt = TCPTV_RTOBASE; else - TCPT_RANGESET(rexmt, TCPTV_RTOBASE * tcp_syn_backoff[sc->sc_rxmits], + TCPT_RANGESET(rexmt, TCPTV_RTOBASE * tcp_backoff[sc->sc_rxmits], tcp_rexmit_min, TCPTV_REXMTMAX); sc->sc_rxttime = ticks + rexmt; sc->sc_rxmits++; Modified: head/sys/netinet/tcp_timer.c ============================================================================== --- head/sys/netinet/tcp_timer.c Wed Feb 20 17:10:30 2019 (r344366) +++ head/sys/netinet/tcp_timer.c Wed Feb 20 17:56:38 2019 (r344367) @@ -233,9 +233,6 @@ tcp_slowtimo(void) VNET_LIST_RUNLOCK_NOSLEEP(); } -int tcp_syn_backoff[TCP_MAXRXTSHIFT + 1] = - { 1, 1, 1, 1, 1, 2, 4, 8, 16, 32, 64, 64, 64 }; - int tcp_backoff[TCP_MAXRXTSHIFT + 1] = { 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 512, 512, 512 }; @@ -671,7 +668,7 @@ tcp_timer_rexmt(void * xtp) TCPSTAT_INC(tcps_rexmttimeo); if ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) - rexmt = TCPTV_RTOBASE * tcp_syn_backoff[tp->t_rxtshift]; + rexmt = TCPTV_RTOBASE * tcp_backoff[tp->t_rxtshift]; else rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; TCPT_RANGESET(tp->t_rxtcur, rexmt, Modified: head/sys/netinet/tcp_timer.h ============================================================================== --- head/sys/netinet/tcp_timer.h Wed Feb 20 17:10:30 2019 (r344366) +++ head/sys/netinet/tcp_timer.h Wed Feb 20 17:56:38 2019 (r344367) @@ -199,7 +199,6 @@ extern int tcp_rexmit_slop; extern int tcp_msl; extern int tcp_ttl; /* time to live for TCP segs */ extern int tcp_backoff[]; -extern int tcp_syn_backoff[]; extern int tcp_totbackoff; extern int tcp_rexmit_drop_options;