From owner-svn-src-head@freebsd.org Fri Feb 17 05:22:59 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id EFE85CDFB24; Fri, 17 Feb 2017 05:22:59 +0000 (UTC) (envelope-from mav@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 mx1.freebsd.org (Postfix) with ESMTPS id 9D63912C2; Fri, 17 Feb 2017 05:22:59 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v1H5MwC0027648; Fri, 17 Feb 2017 05:22:58 GMT (envelope-from mav@FreeBSD.org) Received: (from mav@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v1H5MwGK027647; Fri, 17 Feb 2017 05:22:58 GMT (envelope-from mav@FreeBSD.org) Message-Id: <201702170522.v1H5MwGK027647@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mav set sender to mav@FreeBSD.org using -f From: Alexander Motin Date: Fri, 17 Feb 2017 05:22:58 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r313854 - head/sys/cam/ctl X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Feb 2017 05:23:00 -0000 Author: mav Date: Fri Feb 17 05:22:58 2017 New Revision: 313854 URL: https://svnweb.freebsd.org/changeset/base/313854 Log: Change the way MaxCmdSN is used. Before this change MaxCmdSN was reported as CmdSN + delta, that made it limit number of requests in transmission from the initiator to target, that was pretty useless. After this change MaxCmdSN limits number of requests queued to CTL, i.e. maximal queue depth for the initiator. The default limit is 256 outstanding requests per initiator at a time. This code uses existing cs_outstanding_ctl_pdus counter to track queue depth. It's semantics doen't perfectly match, but close enough to not add another counter. Just don't set the maxtags below 2. MFC after: 2 weeks Modified: head/sys/cam/ctl/ctl_frontend_iscsi.c Modified: head/sys/cam/ctl/ctl_frontend_iscsi.c ============================================================================== --- head/sys/cam/ctl/ctl_frontend_iscsi.c Fri Feb 17 05:09:51 2017 (r313853) +++ head/sys/cam/ctl/ctl_frontend_iscsi.c Fri Feb 17 05:22:58 2017 (r313854) @@ -95,10 +95,9 @@ SYSCTL_INT(_kern_cam_ctl_iscsi, OID_AUTO static int login_timeout = 60; SYSCTL_INT(_kern_cam_ctl_iscsi, OID_AUTO, login_timeout, CTLFLAG_RWTUN, &login_timeout, 60, "Time to wait for ctld(8) to finish Login Phase, in seconds"); -static int maxcmdsn_delta = 256; -SYSCTL_INT(_kern_cam_ctl_iscsi, OID_AUTO, maxcmdsn_delta, CTLFLAG_RWTUN, - &maxcmdsn_delta, 256, "Number of commands the initiator can send " - "without confirmation"); +static int maxtags = 256; +SYSCTL_INT(_kern_cam_ctl_iscsi, OID_AUTO, maxtags, CTLFLAG_RWTUN, + &maxtags, 0, "Max number of requests queued by initiator"); #define CFISCSI_DEBUG(X, ...) \ do { \ @@ -244,7 +243,7 @@ cfiscsi_pdu_update_cmdsn(const struct ic * outside of this range. */ if (ISCSI_SNLT(cmdsn, cs->cs_cmdsn) || - ISCSI_SNGT(cmdsn, cs->cs_cmdsn + maxcmdsn_delta)) { + ISCSI_SNGT(cmdsn, cs->cs_cmdsn - 1 + maxtags)) { CFISCSI_SESSION_UNLOCK(cs); CFISCSI_SESSION_WARN(cs, "received PDU with CmdSN %u, " "while expected %u", cmdsn, cs->cs_cmdsn); @@ -399,7 +398,8 @@ cfiscsi_pdu_prepare(struct icl_pdu *resp (bhssr->bhssr_flags & BHSDI_FLAGS_S)) bhssr->bhssr_statsn = htonl(cs->cs_statsn); bhssr->bhssr_expcmdsn = htonl(cs->cs_cmdsn); - bhssr->bhssr_maxcmdsn = htonl(cs->cs_cmdsn + maxcmdsn_delta); + bhssr->bhssr_maxcmdsn = htonl(cs->cs_cmdsn - 1 + + imax(0, maxtags - cs->cs_outstanding_ctl_pdus)); if (advance_statsn) cs->cs_statsn++;