3150. [func] Improved startup and reconfiguration time by

			enabling zones to load in multiple threads. [RT #25333]

CHANGES

+3150.	[func]		Improved startup and reconfiguration time by
+			enabling zones to load in multiple threads. [RT #25333]
+
+3149.	[placeholder]
+
 3148.	[bug]		Processing of normal queries could be stalled when
 			forwarding a UPDATE message. [RT #24711]
 

bin/named/server.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: server.c,v 1.617 2011/08/30 05:16:10 marka Exp $ */
+/* $Id: server.c,v 1.618 2011/09/02 21:15:30 each Exp $ */
 
 /*! \file */
 
@@ -39,6 +39,7 @@
 #include <isc/parseint.h>
 #include <isc/portset.h>
 #include <isc/print.h>
+#include <isc/refcount.h>
 #include <isc/resource.h>
 #include <isc/sha2.h>
 #include <isc/socket.h>
@@ -215,6 +216,16 @@ struct cfg_context {
 	cfg_aclconfctx_t *		actx;
 };
 
+/*%
+ * Holds state information for the initial zone loading process.
+ * Uses the isc_refcount structure to count the number of views
+ * with pending zone loads, dereferencing as each view finishes.
+ */
+typedef struct {
+		ns_server_t *server;
+		isc_refcount_t refs;
+} ns_zoneload_t;
+
 /*
  * These zones should not leak onto the Internet.
  */
@@ -5216,34 +5227,87 @@ load_configuration(const char *filename, ns_server_t *server,
 }
 
 static isc_result_t
-load_zones(ns_server_t *server, isc_boolean_t stop) {
+view_loaded(void *arg) {
+	isc_result_t result;
+	ns_zoneload_t *zl = (ns_zoneload_t *) arg;
+	ns_server_t *server = zl->server;
+	unsigned int refs;
+
+
+	/*
+	 * Force zone maintenance.  Do this after loading
+	 * so that we know when we need to force AXFR of
+	 * slave zones whose master files are missing.
+	 *
+	 * We use the zoneload reference counter to let us
+	 * know when all views are finished.
+	 */
+	isc_refcount_decrement(&zl->refs, &refs);
+	if (refs != 0)
+		return (ISC_R_SUCCESS);
+
+	isc_refcount_destroy(&zl->refs);
+	isc_mem_put(server->mctx, zl, sizeof (*zl));
+
+	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
+		      ISC_LOG_NOTICE, "all zones loaded");
+	CHECKFATAL(dns_zonemgr_forcemaint(server->zonemgr),
+		   "forcing zone maintenance");
+
+	ns_os_started();
+	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
+		      ISC_LOG_NOTICE, "running");
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+load_zones(ns_server_t *server) {
 	isc_result_t result;
 	dns_view_t *view;
+	ns_zoneload_t *zl;
+	unsigned int refs = 0;
+
+	zl = isc_mem_get(server->mctx, sizeof (*zl));
+	if (zl == NULL)
+		return (ISC_R_NOMEMORY);
+	zl->server = server;
 
 	result = isc_task_beginexclusive(server->task);
 	RUNTIME_CHECK(result == ISC_R_SUCCESS);
 
+	isc_refcount_init(&zl->refs, 1);
+
 	/*
-	 * Load zone data from disk.
+	 * Schedule zones to be loaded from disk.
 	 */
 	for (view = ISC_LIST_HEAD(server->viewlist);
 	     view != NULL;
 	     view = ISC_LIST_NEXT(view, link))
 	{
-		CHECK(dns_view_load(view, stop));
 		if (view->managed_keys != NULL)
 			CHECK(dns_zone_load(view->managed_keys));
 		if (view->redirect != NULL)
 			CHECK(dns_zone_load(view->redirect));
+		isc_refcount_increment(&zl->refs, NULL);
+		CHECK(dns_view_asyncload(view, view_loaded, zl));
 	}
 
-	/*
-	 * Force zone maintenance.  Do this after loading
-	 * so that we know when we need to force AXFR of
-	 * slave zones whose master files are missing.
-	 */
-	CHECK(dns_zonemgr_forcemaint(server->zonemgr));
  cleanup:
+	isc_refcount_decrement(&zl->refs, &refs);
+	if (result != ISC_R_SUCCESS || refs == 0) {
+		isc_refcount_destroy(&zl->refs);
+		isc_mem_put(server->mctx, zl, sizeof (*zl));
+	} else {
+		/*
+		 * Place the task manager into privileged mode.  This
+		 * ensures that after we leave task-exclusive mode, no
+		 * other tasks will be able to run except for the ones
+		 * that are loading zones.
+		 */
+		isc_taskmgr_setmode(ns_g_taskmgr, isc_taskmgrmode_privileged);
+	}
+
 	isc_task_endexclusive(server->task);
 	return (result);
 }
@@ -5331,11 +5395,7 @@ run_server(isc_task_t *task, isc_event_t *event) {
 
 	isc_hash_init();
 
-	CHECKFATAL(load_zones(server, ISC_FALSE), "loading zones");
-
-	ns_os_started();
-	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
-		      ISC_LOG_NOTICE, "running");
+	CHECKFATAL(load_zones(server), "loading zones");
 }
 
 void
@@ -5770,7 +5830,7 @@ reload(ns_server_t *server) {
 	isc_result_t result;
 	CHECK(loadconfig(server));
 
-	result = load_zones(server, ISC_FALSE);
+	result = load_zones(server);
 	if (result == ISC_R_SUCCESS)
 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
 			      NS_LOGMODULE_SERVER, ISC_LOG_INFO,

bin/tests/startperf/README

 These scripts generate a named.conf file with an arbitrary number of
 small zones, for testing startup performance.
 
-To generate a test server with 1000 zones, run:
+To generate a test server with 1000 zones each of which contains 5 A
+records, run:
 
-   $ sh setup.sh 1000 > named.conf
+   $ sh setup.sh 1000 5 > named.conf
 
-Zones are generated with random names, and all of them load from the same
-file: smallzone.db.
+Zones are generated with random names, and the zone files are created
+in the subdirectory "zones".
+
+Or, to generate a test server with 100 zones which all load from the same
+generic file (smallzone.db):
+
+   $ sh setup.sh -s 100 > named.conf
+
+The "number of records" argument is ignored if -s is used.

bin/tests/startperf/clean.sh

+#!/bin/sh
+rm -rf zones
+rm -f named.conf

bin/tests/startperf/makenames.pl

@@ -14,17 +14,19 @@
 # OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 # PERFORMANCE OF THIS SOFTWARE.
 
-# $Id: makenames.pl,v 1.2 2011/07/06 05:05:51 each Exp $
+# $Id: makenames.pl,v 1.3 2011/09/02 21:15:35 each Exp $
 use strict;
 
-die "Usage: makenames.pl <num>" if (@ARGV == 0);
+die "Usage: makenames.pl <num> [<len>]" if (@ARGV == 0 || @ARGV > 2);
+my $len = 10;
+$len = @ARGV[1] if (@ARGV == 2);
 
 my @chars = split("", "abcdefghijklmnopqrstuvwxyz123456789");
 
 srand; 
 for (my $i = 0; $i < @ARGV[0]; $i++) {
         my $name = "";
-        for (my $j = 0; $j < 10; $j++) {
+        for (my $j = 0; $j < $len; $j++) {
                 my $r = rand 35;
                 $name .= $chars[$r];
         }

bin/tests/startperf/mkzonefile.pl

+#!/usr/bin/perl
+#
+# Copyright (C) 2011  Internet Systems Consortium, Inc. ("ISC")
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+# PERFORMANCE OF THIS SOFTWARE.
+
+# $Id: mkzonefile.pl,v 1.2 2011/09/02 21:15:35 each Exp $
+use strict;
+
+die "Usage: makenames.pl zonename num_records" if (@ARGV != 2);
+my $zname = @ARGV[0];
+my $nrecords = @ARGV[1];
+
+my @chars = split("", "abcdefghijklmnopqrstuvwxyz");
+
+print"\$TTL 300	; 5 minutes
+\$ORIGIN $zname.
+@			IN SOA	mname1. . (
+				2011080201 ; serial
+				20         ; refresh (20 seconds)
+				20         ; retry (20 seconds)
+				1814400    ; expire (3 weeks)
+				600        ; minimum (1 hour)
+				)
+			NS	ns
+ns			A	10.53.0.3\n";
+
+srand; 
+for (my $i = 0; $i < $nrecords; $i++) {
+        my $name = "";
+        for (my $j = 0; $j < 8; $j++) {
+                my $r = rand 25;
+                $name .= $chars[$r];
+        }
+        print "$name" . "\tIN\tA\t";
+        my $x = int rand 254;
+        my $y = int rand 254;
+        my $z = int rand 254;
+        print "10.$x.$y.$z\n";
+}
+

bin/tests/startperf/setup.sh

@@ -14,13 +14,30 @@
 # OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 # PERFORMANCE OF THIS SOFTWARE.
 
-# $Id: setup.sh,v 1.3 2011/07/07 23:47:49 tbox Exp $
+# $Id: setup.sh,v 1.4 2011/09/02 21:15:35 each Exp $
 
-if [ "$#" -ne 1 ]; then
-    echo "Usage: $0 <number of zones>"
+usage () {
+    echo "Usage: $0 [-s] <number of zones> [<records per zone>]"
+    echo "       -s: use the same zone file all zones"
     exit 1
+}
+
+if [ "$#" -lt 1 -o "$#" -gt 3 ]; then
+    usage
+fi
+
+single_file=""
+if [ $1 = "-s" ]; then
+    single_file=yes
+    shift
 fi
 
+nzones=$1
+shift
+
+nrecords=5
+[ "$#" -eq 1 ] && nrecords=$1
+
 . ../system/conf.sh
 
 cat << EOF
@@ -59,6 +76,12 @@ logging {
 
 EOF
 
-$PERL makenames.pl $1 | while read zonename; do
+$PERL makenames.pl $nzones | while read zonename; do
+    if [ $single_file ]; then
         echo "zone $zonename { type master; file \"smallzone.db\"; };"
+    else
+        [ -d zones ] || mkdir zones
+        $PERL mkzonefile.pl $zonename $nrecords > zones/$zonename.db
+        echo "zone $zonename { type master; file \"zones/$zonename.db\"; };"
+    fi
 done

lib/dns/include/dns/events.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: events.h,v 1.58 2011/08/30 23:46:53 tbox Exp $ */
+/* $Id: events.h,v 1.59 2011/09/02 21:15:36 each Exp $ */
 
 #ifndef DNS_EVENTS_H
 #define DNS_EVENTS_H 1
@@ -76,6 +76,7 @@
 #define DNS_EVENT_ADBGROWNAMES			(ISC_EVENTCLASS_DNS + 46)
 #define DNS_EVENT_ZONESECURESERIAL		(ISC_EVENTCLASS_DNS + 47)
 #define DNS_EVENT_ZONESECUREDB			(ISC_EVENTCLASS_DNS + 48)
+#define DNS_EVENT_ZONELOAD			(ISC_EVENTCLASS_DNS + 49)
 
 #define DNS_EVENT_FIRSTEVENT			(ISC_EVENTCLASS_DNS + 0)
 #define DNS_EVENT_LASTEVENT			(ISC_EVENTCLASS_DNS + 65535)

lib/dns/include/dns/view.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: view.h,v 1.134 2011/08/02 20:36:13 each Exp $ */
+/* $Id: view.h,v 1.135 2011/09/02 21:15:36 each Exp $ */
 
 #ifndef DNS_VIEW_H
 #define DNS_VIEW_H 1
@@ -76,6 +76,7 @@
 #include <dns/rdatastruct.h>
 #include <dns/rpz.h>
 #include <dns/types.h>
+#include <dns/zt.h>
 
 ISC_LANG_BEGINDECLS
 
@@ -728,14 +729,21 @@ dns_view_load(dns_view_t *view, isc_boolean_t stop);
 
 isc_result_t
 dns_view_loadnew(dns_view_t *view, isc_boolean_t stop);
+
+isc_result_t
+dns_view_asyncload(dns_view_t *view, dns_zt_allloaded_t callback, void *arg);
 /*%<
  * Load zones attached to this view.  dns_view_load() loads
  * all zones whose master file has changed since the last
  * load; dns_view_loadnew() loads only zones that have never
  * been loaded.
  *
+ * dns_view_asyncload() loads zones asynchronously.  When all zones
+ * in the view have finished loading, 'callback' is called with argument
+ * 'arg' to inform the caller.
+ *
  * If 'stop' is ISC_TRUE, stop on the first error and return it.
- * If 'stop' is ISC_FALSE, ignore errors.
+ * If 'stop' is ISC_FALSE (or we are loading asynchronously), ignore errors.
  *
  * Requires:
  *

lib/dns/include/dns/zone.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: zone.h,v 1.192 2011/08/30 05:16:15 marka Exp $ */
+/* $Id: zone.h,v 1.193 2011/09/02 21:15:36 each Exp $ */
 
 #ifndef DNS_ZONE_H
 #define DNS_ZONE_H 1
@@ -35,6 +35,7 @@
 #include <dns/masterdump.h>
 #include <dns/rdatastruct.h>
 #include <dns/types.h>
+#include <dns/zt.h>
 
 typedef enum {
 	dns_zone_none,
@@ -287,6 +288,7 @@ dns_zone_loadnew(dns_zone_t *zone);
 
 isc_result_t
 dns_zone_loadandthaw(dns_zone_t *zone);
+
 /*%<
  *	Cause the database to be loaded from its backing store.
  *	Confirm that the minimum requirements for the zone type are
@@ -311,6 +313,25 @@ dns_zone_loadandthaw(dns_zone_t *zone);
  *\li	Any result value from dns_db_load().
  */
 
+isc_result_t
+dns_zone_asyncload(dns_zone_t *zone, dns_zt_zoneloaded_t done, void *arg);
+/*%<
+ * Cause the database to be loaded from its backing store asynchronously.
+ * Other zone maintenance functions are suspended until this is complete.
+ * When finished, 'done' is called to inform the caller, with 'arg' as
+ * its first argument and 'zone' as its second.  (Normally, 'arg' is
+ * expected to point to the zone table but is left undefined for testing
+ * purposes.)
+ */
+
+isc_boolean_t
+dns__zone_loadpending(dns_zone_t *zone);
+/*%<
+ * Indicates whether the zone is waiting to be loaded asynchronously.
+ * (Not currently intended for use outside of this module and associated
+ * tests.)
+ */
+
 void
 dns_zone_attach(dns_zone_t *source, dns_zone_t **target);
 /*%<
@@ -1427,6 +1448,14 @@ dns_zonemgr_forcemaint(dns_zonemgr_t *zmgr);
  * earliest convenience.
  */
 
+void
+dns__zonemgr_run(isc_task_t *task, isc_event_t *event);
+/*%<
+ * Event handler to call dns_zonemgr_forcemaint(); used to start
+ * zone operations from a unit test.  Not intended for use outside
+ * libdns or related tests.
+ */
+
 void
 dns_zonemgr_resumexfrs(dns_zonemgr_t *zmgr);
 /*%<

lib/dns/include/dns/zt.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: zt.h,v 1.38 2007/06/19 23:47:17 tbox Exp $ */
+/* $Id: zt.h,v 1.39 2011/09/02 21:15:37 each Exp $ */
 
 #ifndef DNS_ZT_H
 #define DNS_ZT_H 1
@@ -30,6 +30,21 @@
 
 ISC_LANG_BEGINDECLS
 
+typedef isc_result_t
+(*dns_zt_allloaded_t)(void *arg);
+/*%<
+ * Method prototype: when all pending zone loads are complete,
+ * the zone table can inform the caller via a callback function with
+ * this signature.
+ */
+
+typedef isc_result_t
+(*dns_zt_zoneloaded_t)(dns_zt_t *zt, dns_zone_t *zone, isc_task_t *task);
+/*%<
+ * Method prototype: when a zone finishes loading, the zt object
+ * can be informed via a callback function with this signature.
+ */
+
 isc_result_t
 dns_zt_create(isc_mem_t *mctx, dns_rdataclass_t rdclass, dns_zt_t **zt);
 /*%<
@@ -134,6 +149,9 @@ dns_zt_load(dns_zt_t *zt, isc_boolean_t stop);
 
 isc_result_t
 dns_zt_loadnew(dns_zt_t *zt, isc_boolean_t stop);
+
+isc_result_t
+dns_zt_asyncload(dns_zt_t *zt, dns_zt_allloaded_t alldone, void *arg);
 /*%<
  * Load all zones in the table.  If 'stop' is ISC_TRUE,
  * stop on the first error and return it.  If 'stop'
@@ -142,6 +160,10 @@ dns_zt_loadnew(dns_zt_t *zt, isc_boolean_t stop);
  * dns_zt_loadnew() only loads zones that are not yet loaded.
  * dns_zt_load() also loads zones that are already loaded and
  * and whose master file has changed since the last load.
+ * dns_zt_asyncload() loads zones asynchronously; when all
+ * zones in the zone table have finished loaded (or failed due
+ * to errors), the caller is informed by calling 'alldone'
+ * with an argument of 'arg'.
  *
  * Requires:
  * \li	'zt' to be valid
@@ -178,6 +200,16 @@ dns_zt_apply2(dns_zt_t *zt, isc_boolean_t stop, isc_result_t *sub,
  *	any error code from 'action'.
  */
 
+isc_boolean_t
+dns_zt_loadspending(dns_zt_t *zt);
+/*%<
+ * Returns ISC_TRUE if and only if there are zones still waiting to
+ * be loaded in zone table 'zt'.
+ *
+ * Requires:
+ * \li	'zt' to be valid.
+ */
+
 ISC_LANG_ENDDECLS
 
 #endif /* DNS_ZT_H */

lib/dns/tests/Makefile.in

@@ -12,7 +12,7 @@
 # OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 # PERFORMANCE OF THIS SOFTWARE.
 
-# $Id: Makefile.in,v 1.7 2011/08/23 01:29:38 each Exp $
+# $Id: Makefile.in,v 1.8 2011/09/02 21:15:37 each Exp $
 
 srcdir =	@srcdir@
 VPATH =		@srcdir@
@@ -37,12 +37,12 @@ DNSDEPLIBS =	../libdns.@A@
 LIBS =		@LIBS@ @ATFLIBS@
 
 OBJS =		dnstest.@O@
-SRCS =		dnstest.c master_test.c time_test.c update_test.c \
-		zonemgr_test.c dbiterator_test.c
+SRCS =		dnstest.c master_test.c dbiterator_test.c time_test.c \
+		update_test.c zonemgr_test.c zt_test.c
 
 SUBDIRS =
-TARGETS =	master_test@EXEEXT@ time_test@EXEEXT@ update_test@EXEEXT@ \
-		zonemgr_test@EXEEXT@ dbiterator_test@EXEEXT@
+TARGETS =	master_test@EXEEXT@ dbiterator_test@EXEEXT@ time_test@EXEEXT@ \
+		update_test@EXEEXT@ zonemgr_test@EXEEXT@ zt_test@EXEEXT@
 
 @BIND9_MAKE_RULES@
 
@@ -71,6 +71,11 @@ dbiterator_test@EXEEXT@: dbiterator_test.@O@ dnstest.@O@ ${ISCDEPLIBS} ${DNSDEPL
 			dbiterator_test.@O@ dnstest.@O@ ${DNSLIBS} \
 				${ISCLIBS} ${LIBS}
 
+zt_test@EXEEXT@: zt_test.@O@ dnstest.@O@ ${ISCDEPLIBS} ${DNSDEPLIBS}
+	${LIBTOOL_MODE_LINK} ${PURIFY} ${CC} ${CFLAGS} ${LDFLAGS} -o $@ \
+			zt_test.@O@ dnstest.@O@ ${DNSLIBS} \
+				${ISCLIBS} ${LIBS}
+
 unit::
 	sh ${top_srcdir}/unit/unittest.sh
 

lib/dns/tests/dnstest.c

@@ -14,12 +14,14 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dnstest.c,v 1.4 2011/07/06 01:36:32 each Exp $ */
+/* $Id: dnstest.c,v 1.5 2011/09/02 21:15:37 each Exp $ */
 
 /*! \file */
 
 #include <config.h>
 
+#include <unistd.h>
+
 #include <isc/app.h>
 #include <isc/buffer.h>
 #include <isc/entropy.h>
@@ -32,9 +34,12 @@
 #include <isc/timer.h>
 #include <isc/util.h>
 
+#include <dns/fixedname.h>
 #include <dns/log.h>
 #include <dns/name.h>
 #include <dns/result.h>
+#include <dns/view.h>
+#include <dns/zone.h>
 
 #include <dst/dst.h>
 
@@ -44,8 +49,11 @@ isc_mem_t *mctx = NULL;
 isc_entropy_t *ectx = NULL;
 isc_log_t *lctx = NULL;
 isc_taskmgr_t *taskmgr = NULL;
+isc_task_t *maintask = NULL;
 isc_timermgr_t *timermgr = NULL;
 isc_socketmgr_t *socketmgr = NULL;
+dns_zonemgr_t *zonemgr = NULL;
+isc_boolean_t app_running = ISC_FALSE;
 int ncpus;
 
 static isc_boolean_t hash_active = ISC_FALSE, dst_active = ISC_FALSE;
@@ -67,8 +75,12 @@ static isc_logcategory_t categories[] = {
 
 static void
 cleanup_managers() {
+	if (app_running)
+		isc_app_finish();
 	if (socketmgr != NULL)
 		isc_socketmgr_destroy(&socketmgr);
+	if (maintask != NULL)
+		isc_task_destroy(&maintask);
 	if (taskmgr != NULL)
 		isc_taskmgr_destroy(&taskmgr);
 	if (timermgr != NULL)
@@ -87,6 +99,8 @@ create_managers() {
 	CHECK(isc_taskmgr_create(mctx, ncpus, 0, &taskmgr));
 	CHECK(isc_timermgr_create(mctx, &timermgr));
 	CHECK(isc_socketmgr_create(mctx, &socketmgr));
+	CHECK(isc_task_create(taskmgr, 0, &maintask));
+	CHECK(isc_app_start());
 	return (ISC_R_SUCCESS);
 
   cleanup:
@@ -134,6 +148,14 @@ dns_test_begin(FILE *logfile, isc_boolean_t start_managers) {
 	if (start_managers)
 		CHECK(create_managers());
 
+	/*
+	 * atf-run changes us to a /tmp directory, so tests
+	 * that access test data files must first chdir to the proper
+	 * location.
+	 */
+	if (chdir(TESTS) == -1)
+		CHECK(ISC_R_FAILURE);
+
 	return (ISC_R_SUCCESS);
 
   cleanup:
@@ -162,3 +184,114 @@ dns_test_end() {
 		isc_mem_destroy(&mctx);
 }
 
+/*
+ * Create a zone with origin 'name', return a pointer to the zone object in
+ * 'zonep'.  If 'view' is set, add the zone to that view; otherwise, create
+ * a new view for the purpose. 
+ *
+ * If the created view is going to be needed by the caller subsequently,
+ * then 'keepview' should be set to true; this will prevent the view
+ * from being detached.  In this case, the caller is responsible for
+ * detaching the view.
+ */
+isc_result_t
+dns_test_makezone(const char *name, dns_zone_t **zonep, dns_view_t *view,
+		  isc_boolean_t keepview)
+{
+	isc_result_t result;
+	dns_zone_t *zone = NULL;
+	isc_buffer_t buffer;
+	dns_fixedname_t fixorigin;
+