1905. [bug] Recursive clients soft quota support wasn't working

                        as expected. [RT #15103]

CHANGES

+1905.	[bug]		Recursive clients soft quota support wasn't working
+			as expected. [RT #15103]
+
 1904.	[bug]		A escaped character is, potentially, converted to
 			the output character set too early. [RT #14666]
 

bin/named/client.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: client.c,v 1.228 2005/06/07 00:15:59 marka Exp $ */
+/* $Id: client.c,v 1.229 2005/07/27 02:28:58 marka Exp $ */
 
 #include <config.h>
 
@@ -181,26 +181,32 @@ static void client_request(isc_task_t *task, isc_event_t *event);
 static void ns_client_dumpmessage(ns_client_t *client, const char *reason);
 
 void
-ns_client_recursing(ns_client_t *client, isc_boolean_t killoldest) {
-	ns_client_t *oldest;
+ns_client_recursing(ns_client_t *client) {
 	REQUIRE(NS_CLIENT_VALID(client));
 
 	LOCK(&client->manager->lock);
-	if (killoldest) {
-		oldest = ISC_LIST_HEAD(client->manager->recursing);
-		if (oldest != NULL) {
-			ns_query_cancel(oldest);
-			ISC_LIST_UNLINK(*oldest->list, oldest, link);
-			ISC_LIST_APPEND(client->manager->active, oldest, link);
-			oldest->list = &client->manager->active;
-		}
-	}
 	ISC_LIST_UNLINK(*client->list, client, link);
 	ISC_LIST_APPEND(client->manager->recursing, client, link);
 	client->list = &client->manager->recursing;
 	UNLOCK(&client->manager->lock);
 }
 
+void
+ns_client_killoldestquery(ns_client_t *client) {
+	ns_client_t *oldest;
+	REQUIRE(NS_CLIENT_VALID(client));
+
+	LOCK(&client->manager->lock);
+	oldest = ISC_LIST_HEAD(client->manager->recursing);
+	if (oldest != NULL) {
+		ns_query_cancel(oldest);
+		ISC_LIST_UNLINK(*oldest->list, oldest, link);
+		ISC_LIST_APPEND(client->manager->active, oldest, link);
+		oldest->list = &client->manager->active;
+	}
+	UNLOCK(&client->manager->lock);
+}
+
 void
 ns_client_settimeout(ns_client_t *client, unsigned int seconds) {
 	isc_result_t result;

bin/named/include/named/client.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: client.h,v 1.75 2005/07/18 05:58:57 marka Exp $ */
+/* $Id: client.h,v 1.76 2005/07/27 02:28:59 marka Exp $ */
 
 #ifndef NAMED_CLIENT_H
 #define NAMED_CLIENT_H 1
@@ -326,10 +326,15 @@ ns_client_aclmsg(const char *msg, dns_name_t *name, dns_rdatatype_t type,
 	 DNS_RDATACLASS_FORMATSIZE + sizeof(x) + sizeof("'/'"))
 
 void
-ns_client_recursing(ns_client_t *client, isc_boolean_t killoldest);
+ns_client_recursing(ns_client_t *client);
 /*%
- * Add client to end of recursing list.  If 'killoldest' is true
- * kill the oldest recursive client (list head). 
+ * Add client to end of th recursing list.
+ */
+
+void
+ns_client_killoldestquery(ns_client_t *client);
+/*%
+ * Kill the oldest recursive query (recursing list head).
  */
 
 void

bin/named/query.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: query.c,v 1.268 2005/06/27 00:15:42 marka Exp $ */
+/* $Id: query.c,v 1.269 2005/07/27 02:28:58 marka Exp $ */
 
 /*! \file */
 
@@ -2701,33 +2701,37 @@ query_recurse(ns_client_t *client, dns_rdatatype_t qtype, dns_name_t *qdomain,
 	 * connection was accepted (if allowed by the TCP quota).
 	 */
 	if (client->recursionquota == NULL) {
-		isc_boolean_t killoldest = ISC_FALSE;
 		result = isc_quota_attach(&ns_g_server->recursionquota,
 					  &client->recursionquota);
-		if (result == ISC_R_SOFTQUOTA) {
+		if  (result == ISC_R_SOFTQUOTA) {
 			ns_client_log(client, NS_LOGCATEGORY_CLIENT,
 				      NS_LOGMODULE_QUERY, ISC_LOG_WARNING,
-				      "recursive-clients limit exceeded, "
+				      "recursive-clients soft limit exceeded, "
 				      "aborting oldest query");
-			killoldest = ISC_TRUE;
-			result = ISC_R_SUCCESS;
-		}
-		if (dns_resolver_nrunning(client->view->resolver) >
-		    (unsigned int)ns_g_server->recursionquota.max)
-			result = ISC_R_QUOTA;
-		if (result == ISC_R_SUCCESS && !client->mortal &&
-		    (client->attributes & NS_CLIENTATTR_TCP) == 0)
-			result = ns_client_replace(client);
-		if (result != ISC_R_SUCCESS) {
+			ns_client_killoldestquery(client);
+			result == ISC_R_SUCCESS;
+		} else if (result == ISC_R_QUOTA) {
 			ns_client_log(client, NS_LOGCATEGORY_CLIENT,
 				      NS_LOGMODULE_QUERY, ISC_LOG_WARNING,
 				      "no more recursive clients: %s",
 				      isc_result_totext(result));
-			if (client->recursionquota != NULL)
+			ns_client_killoldestquery(client);
+		}
+		if (result == ISC_R_SUCCESS && !client->mortal &&
+		    (client->attributes & NS_CLIENTATTR_TCP) == 0) {
+			result = ns_client_replace(client);
+			if (result != ISC_R_SUCCESS) {
+				ns_client_log(client, NS_LOGCATEGORY_CLIENT,
+					      NS_LOGMODULE_QUERY,
+					      ISC_LOG_WARNING,
+					      "ns_client_replace() failed: %s",
+					      isc_result_totext(result));
 				isc_quota_detach(&client->recursionquota);
-			return (result);
+			}
 		}
-		ns_client_recursing(client, killoldest);
+		if (result != ISC_R_SUCCESS)
+			return (result);
+		ns_client_recursing(client);
 	}
 
 	/*

bin/named/server.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: server.c,v 1.445 2005/06/27 00:15:42 marka Exp $ */
+/* $Id: server.c,v 1.446 2005/07/27 02:28:58 marka Exp $ */
 
 /*! \file */
 
@@ -1882,7 +1882,7 @@ configure_server_quota(cfg_obj_t **maps, const char *name, isc_quota_t *quota)
 
 	result = ns_config_get(maps, name, &obj);
 	INSIST(result == ISC_R_SUCCESS);
-	quota->max = cfg_obj_asuint32(obj);
+	isc_quota_max(quota, cfg_obj_asuint32(obj));
 }
 
 /*
@@ -2309,6 +2309,11 @@ load_configuration(const char *filename, ns_server_t *server,
 	configure_server_quota(maps, "tcp-clients", &server->tcpquota);
 	configure_server_quota(maps, "recursive-clients",
 			       &server->recursionquota);
+	if (server->recursionquota.max > 1000)
+		isc_quota_soft(&server->recursionquota,
+			       server->recursionquota.max - 100);
+	else
+		isc_quota_soft(&server->recursionquota, 0);
 
 	CHECK(configure_view_acl(NULL, config, "blackhole", &aclconfctx,
 				 ns_g_mctx, &server->blackholeacl));
@@ -3036,7 +3041,6 @@ ns_server_create(isc_mem_t *mctx, ns_server_t **serverp) {
 	RUNTIME_CHECK(result == ISC_R_SUCCESS);
 	result = isc_quota_init(&server->recursionquota, 100);
 	RUNTIME_CHECK(result == ISC_R_SUCCESS);
-	isc_quota_soft(&server->recursionquota, ISC_FALSE);
 
 	result = dns_aclenv_init(mctx, &server->aclenv);
 	RUNTIME_CHECK(result == ISC_R_SUCCESS);
@@ -4147,12 +4151,13 @@ ns_server_status(ns_server_t *server, isc_buffer_t *text) {
 		     "xfers deferred: %u\n"
 		     "soa queries in progress: %u\n"
 		     "query logging is %s\n"
-		     "recursive clients: %d/%d\n"
+		     "recursive clients: %d/%d/%d\n"
 		     "tcp clients: %d/%d\n"
 		     "server is up and running",
 		     zonecount, ns_g_debuglevel, xferrunning, xferdeferred,
 		     soaqueries, server->log_queries ? "ON" : "OFF",
-		     server->recursionquota.used, server->recursionquota.max,
+		     server->recursionquota.used, server->recursionquota.soft,
+		     server->recursionquota.max,
 		     server->tcpquota.used, server->tcpquota.max);
 	if (n >= isc_buffer_availablelength(text))
 		return (ISC_R_NOSPACE);

lib/isc/include/isc/quota.h

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: quota.h,v 1.12 2005/04/29 00:23:42 marka Exp $ */
+/* $Id: quota.h,v 1.13 2005/07/27 02:29:01 marka Exp $ */
 
 #ifndef ISC_QUOTA_H
 #define ISC_QUOTA_H 1
@@ -72,9 +72,15 @@ isc_quota_destroy(isc_quota_t *quota);
  */
 
 void
-isc_quota_soft(isc_quota_t *quota, isc_boolean_t soft);
+isc_quota_soft(isc_quota_t *quota, int soft);
 /*%<
- * Turn on/off soft quotas.
+ * Set a soft quota.
+ */
+
+void
+isc_quota_max(isc_quota_t *quota, int max);
+/*%<
+ * Re-set a maximum quota.
  */
 
 isc_result_t
@@ -83,9 +89,9 @@ isc_quota_reserve(isc_quota_t *quota);
  * Attempt to reserve one unit of 'quota'.
  *
  * Returns:
- *\li 	#ISC_R_SUCCESS	Success
- *\li	#ISC_R_SOFTQUOTA	Success soft quota reached
- *\li	#ISC_R_QUOTA	Quota is full
+ * \li 	#ISC_R_SUCCESS		Success
+ * \li	#ISC_R_SOFTQUOTA	Success soft quota reached
+ * \li	#ISC_R_QUOTA		Quota is full
  */
 
 void

lib/isc/quota.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: quota.c,v 1.15 2005/04/29 00:23:29 marka Exp $ */
+/* $Id: quota.c,v 1.16 2005/07/27 02:29:00 marka Exp $ */
 
 /*! \file */
 
@@ -30,38 +30,45 @@ isc_result_t
 isc_quota_init(isc_quota_t *quota, int max) {
 	quota->max = max;
 	quota->used = 0;
-	quota->soft = ISC_FALSE;
+	quota->soft = 0;
 	return (isc_mutex_init(&quota->lock));
 }
 
 void
 isc_quota_destroy(isc_quota_t *quota) {
 	INSIST(quota->used == 0);
-	quota->max = -1;
-	quota->used = -1;
-	quota->soft = ISC_FALSE;
+	quota->max = 0;
+	quota->used = 0;
+	quota->soft = 0;
 	DESTROYLOCK(&quota->lock);
 }
 
 void
-isc_quota_soft(isc_quota_t *quota, isc_boolean_t soft) {
+isc_quota_soft(isc_quota_t *quota, int soft) {
+	LOCK(&quota->lock);
 	quota->soft = soft;
+	UNLOCK(&quota->lock);
+}
+
+void
+isc_quota_max(isc_quota_t *quota, int max) {
+	LOCK(&quota->lock);
+	quota->max = max;
+	UNLOCK(&quota->lock);
 }
 
 isc_result_t
 isc_quota_reserve(isc_quota_t *quota) {
 	isc_result_t result;
 	LOCK(&quota->lock);
-	if (quota->used < quota->max) {
-		quota->used++;
-		result = ISC_R_SUCCESS;
-	} else {
-		if (quota->soft) {
-			quota->used++;
+	if (quota->max == 0 || quota->used < quota->max) {
+		if (quota->soft == 0 || quota->used < quota->soft)
+			result = ISC_R_SUCCESS;
+		else
 			result = ISC_R_SOFTQUOTA;
-		} else
-			result = ISC_R_QUOTA;
-	}
+		quota->used++;
+	} else
+		result = ISC_R_QUOTA;
 	UNLOCK(&quota->lock);
 	return (result);
 }