From owner-svn-src-all@freebsd.org Fri Aug 2 18:01:48 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 444DEB80F9; Fri, 2 Aug 2019 18:01:48 +0000 (UTC) (envelope-from markj@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 460Zjm187Cz4JpN; Fri, 2 Aug 2019 18:01:48 +0000 (UTC) (envelope-from markj@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 0A89265E7; Fri, 2 Aug 2019 18:01:48 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x72I1lbe023740; Fri, 2 Aug 2019 18:01:47 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x72I1lLA023737; Fri, 2 Aug 2019 18:01:47 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201908021801.x72I1lLA023737@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Fri, 2 Aug 2019 18:01:47 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r350540 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: markj X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 350540 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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: Fri, 02 Aug 2019 18:01:48 -0000 Author: markj Date: Fri Aug 2 18:01:47 2019 New Revision: 350540 URL: https://svnweb.freebsd.org/changeset/base/350540 Log: Only check the blessings table for known LORs. Previously we would check for blessings before marking a given lock pair as reversed, so each "reversed" lock acquisition would require a linear scan of the table. Instead, check the table after marking the pair as reversed but before generating a report. Reviewed by: jhb MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21135 Modified: head/sys/kern/subr_witness.c Modified: head/sys/kern/subr_witness.c ============================================================================== --- head/sys/kern/subr_witness.c Fri Aug 2 16:05:36 2019 (r350539) +++ head/sys/kern/subr_witness.c Fri Aug 2 18:01:47 2019 (r350540) @@ -1344,14 +1344,6 @@ witness_checkorder(struct lock_object *lock, int flags * is allowed or has already been yelled about. */ - /* - * If the lock order is blessed, just bail. We don't - * look for other lock order violations though, which - * may be a bug. - */ - if (blessed(w, w1)) - goto out; - /* Bail if this violation is known */ if (w_rmatrix[w1->w_index][w->w_index] & WITNESS_REVERSAL) goto out; @@ -1361,6 +1353,14 @@ witness_checkorder(struct lock_object *lock, int flags w_rmatrix[w->w_index][w1->w_index] |= WITNESS_REVERSAL; w->w_reversed = w1->w_reversed = 1; witness_increment_graph_generation(); + + /* + * If the lock order is blessed, bail before logging + * anything. We don't look for other lock order + * violations though, which may be a bug. + */ + if (blessed(w, w1)) + goto out; mtx_unlock_spin(&w_mtx); #ifdef WITNESS_NO_VNODE @@ -2650,6 +2650,9 @@ restart: &tmp_data2->wlod_stack); } mtx_unlock_spin(&w_mtx); + + if (blessed(tmp_w1, tmp_w2)) + continue; sbuf_printf(sb, "\nLock order reversal between \"%s\"(%s) and \"%s\"(%s)!\n",