From owner-svn-src-head@FreeBSD.ORG  Tue Dec  3 21:55:58 2013
Return-Path: <owner-svn-src-head@FreeBSD.ORG>
Delivered-To: svn-src-head@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id 7E8BF84C;
 Tue,  3 Dec 2013 21:55:58 +0000 (UTC)
Received: from svn.freebsd.org (svn.freebsd.org
 [IPv6:2001:1900:2254:2068::e6a:0])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by mx1.freebsd.org (Postfix) with ESMTPS id 6A265159B;
 Tue,  3 Dec 2013 21:55:58 +0000 (UTC)
Received: from svn.freebsd.org ([127.0.1.70])
 by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id rB3LtwvY008302;
 Tue, 3 Dec 2013 21:55:58 GMT (envelope-from cperciva@svn.freebsd.org)
Received: (from cperciva@localhost)
 by svn.freebsd.org (8.14.7/8.14.7/Submit) id rB3LtwfQ008301;
 Tue, 3 Dec 2013 21:55:58 GMT (envelope-from cperciva@svn.freebsd.org)
Message-Id: <201312032155.rB3LtwfQ008301@svn.freebsd.org>
From: Colin Percival <cperciva@FreeBSD.org>
Date: Tue, 3 Dec 2013 21:55:58 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r258894 - head/etc
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: 2.1.17
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 03 Dec 2013 21:55:58 -0000

Author: cperciva
Date: Tue Dec  3 21:55:57 2013
New Revision: 258894
URL: http://svnweb.freebsd.org/changeset/base/258894

Log:
  The rc system aggressively caches the contents of /etc/rc.conf in order to
  improve boot performance; this produces arguably astonishing (non-)results
  if /etc/rc.conf is modified during the boot process.
  
  Since performance considerations make it infeasible to automatically detect
  if the cached /etc/rc.conf parameters should be invalidated, provide a
  mechanism for explicitly requesting that /etc/rc.conf be reloaded: Catch
  SIGALRM and reload /etc/rc.conf if it is received.
  
  Discussed on:	freebsd-rc
  MFC after:	3 days

Modified:
  head/etc/rc

Modified: head/etc/rc
==============================================================================
--- head/etc/rc	Tue Dec  3 21:35:25 2013	(r258893)
+++ head/etc/rc	Tue Dec  3 21:55:57 2013	(r258894)
@@ -71,6 +71,11 @@ fi
 . /etc/rc.subr
 load_rc_config 'XXX'
 
+# If we receive a SIGALRM, re-source /etc/rc.conf; this allows rc.d
+# scripts to perform "boot-time configuration" including enabling and
+# disabling rc.d scripts which appear later in the boot order.
+trap "_rc_conf_loaded=false; load_rc_config 'XXX'" ALRM
+
 skip="-s nostart"
 if [ `/sbin/sysctl -n security.jail.jailed` -eq 1 ]; then
 	skip="$skip -s nojail"