From owner-svn-src-all@freebsd.org Thu May 9 07:11:10 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 14CC6159F6EC; Thu, 9 May 2019 07:11:10 +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 A922081930; Thu, 9 May 2019 07:11:09 +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 845D919B6C; Thu, 9 May 2019 07:11:09 +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 x497B9Cc005307; Thu, 9 May 2019 07:11:09 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x497B8DY004889; Thu, 9 May 2019 07:11:08 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201905090711.x497B8DY004889@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Thu, 9 May 2019 07:11:08 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r347381 - head/sys/netinet/cc X-SVN-Group: head X-SVN-Commit-Author: tuexen X-SVN-Commit-Paths: head/sys/netinet/cc X-SVN-Commit-Revision: 347381 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: A922081930 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.95 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; NEURAL_HAM_SHORT(-0.95)[-0.948,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] 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: Thu, 09 May 2019 07:11:10 -0000 Author: tuexen Date: Thu May 9 07:11:08 2019 New Revision: 347381 URL: https://svnweb.freebsd.org/changeset/base/347381 Log: Prevent cwnd to collapse down to 1 MSS after exiting recovery. This is descrined in RFC 6582, which updates RFC 3782. Submitted by: Richard Scheffenegger Reviewed by: lstewart@ MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D17614 Modified: head/sys/netinet/cc/cc_cubic.c head/sys/netinet/cc/cc_htcp.c head/sys/netinet/cc/cc_newreno.c Modified: head/sys/netinet/cc/cc_cubic.c ============================================================================== --- head/sys/netinet/cc/cc_cubic.c Thu May 9 04:16:31 2019 (r347380) +++ head/sys/netinet/cc/cc_cubic.c Thu May 9 07:11:08 2019 (r347381) @@ -324,7 +324,12 @@ cubic_post_recovery(struct cc_var *ccv) pipe = CCV(ccv, snd_max) - ccv->curack; if (pipe < CCV(ccv, snd_ssthresh)) - CCV(ccv, snd_cwnd) = pipe + CCV(ccv, t_maxseg); + /* + * Ensure that cwnd does not collapse to 1 MSS under + * adverse conditions. Implements RFC6582 + */ + CCV(ccv, snd_cwnd) = max(pipe, CCV(ccv, t_maxseg)) + + CCV(ccv, t_maxseg); else /* Update cwnd based on beta and adjusted max_cwnd. */ CCV(ccv, snd_cwnd) = max(1, ((CUBIC_BETA * Modified: head/sys/netinet/cc/cc_htcp.c ============================================================================== --- head/sys/netinet/cc/cc_htcp.c Thu May 9 04:16:31 2019 (r347380) +++ head/sys/netinet/cc/cc_htcp.c Thu May 9 07:11:08 2019 (r347381) @@ -366,7 +366,12 @@ htcp_post_recovery(struct cc_var *ccv) pipe = CCV(ccv, snd_max) - ccv->curack; if (pipe < CCV(ccv, snd_ssthresh)) - CCV(ccv, snd_cwnd) = pipe + CCV(ccv, t_maxseg); + /* + * Ensure that cwnd down not collape to 1 MSS under + * adverse conditions. Implements RFC6582 + */ + CCV(ccv, snd_cwnd) = max(pipe, CCV(ccv, t_maxseg)) + + CCV(ccv, t_maxseg); else CCV(ccv, snd_cwnd) = max(1, ((htcp_data->beta * htcp_data->prev_cwnd / CCV(ccv, t_maxseg)) Modified: head/sys/netinet/cc/cc_newreno.c ============================================================================== --- head/sys/netinet/cc/cc_newreno.c Thu May 9 04:16:31 2019 (r347380) +++ head/sys/netinet/cc/cc_newreno.c Thu May 9 07:11:08 2019 (r347381) @@ -295,7 +295,12 @@ newreno_post_recovery(struct cc_var *ccv) pipe = CCV(ccv, snd_max) - ccv->curack; if (pipe < CCV(ccv, snd_ssthresh)) - CCV(ccv, snd_cwnd) = pipe + CCV(ccv, t_maxseg); + /* + * Ensure that cwnd does not collapse to 1 MSS under + * adverse conditons. Implements RFC6582 + */ + CCV(ccv, snd_cwnd) = max(pipe, CCV(ccv, t_maxseg)) + + CCV(ccv, t_maxseg); else CCV(ccv, snd_cwnd) = CCV(ccv, snd_ssthresh); }