Remove the keep-response-order ACL map

The keep-response-order option has been obsoleted, and in this commit,
remove the keep-response-order ACL map rendering the option no-op, the
call the isc_nm_sequential() and the now unused isc_nm_sequential()
function itself.

bin/named/server.c

@@ -8698,15 +8698,6 @@ load_configuration(const char *filename, named_server_t *server,
 					     server->sctx->blackholeacl);
 	}
 
-	/*
-	 * Set "keep-response-order". Only legal at options or
-	 * global defaults level.
-	 */
-	CHECK(configure_view_acl(NULL, config, named_g_config,
-				 "keep-response-order", NULL,
-				 named_g_aclconfctx, named_g_mctx,
-				 &server->sctx->keepresporder));
-
 	obj = NULL;
 	result = named_config_get(maps, "match-mapped-addresses", &obj);
 	INSIST(result == ISC_R_SUCCESS);

lib/bind9/check.c

@@ -529,11 +529,9 @@ check_viewacls(cfg_aclconfctx_t *actx, const cfg_obj_t *voptions,
 	int i = 0;
 
 	static const char *acls[] = {
-		"allow-query",	     "allow-query-on",
-		"allow-query-cache", "allow-query-cache-on",
-		"blackhole",	     "keep-response-order",
-		"match-clients",     "match-destinations",
-		"sortlist",	     NULL
+		"allow-query",		"allow-query-on", "allow-query-cache",
+		"allow-query-cache-on", "blackhole",	  "match-clients",
+		"match-destinations",	"sortlist",	  NULL
 	};
 
 	while (acls[i] != NULL) {

lib/isc/include/isc/netmgr.h

@@ -395,24 +395,6 @@ isc_nm_listentlsdns(isc_nm_t *mgr, isc_sockaddr_t *iface,
  * Same as isc_nm_listentcpdns but for an SSL (DoT) socket.
  */
 
-void
-isc_nm_sequential(isc_nmhandle_t *handle);
-/*%<
- * Disable pipelining on this connection. Each DNS packet will be only
- * processed after the previous completes.
- *
- * The socket must be unpaused after the query is processed.  This is done
- * the response is sent, or if we're dropping the query, it will be done
- * when a handle is fully dereferenced by calling the socket's
- * closehandle_cb callback.
- *
- * Note: This can only be run while a message is being processed; if it is
- * run before any messages are read, no messages will be read.
- *
- * Also note: once this has been set, it cannot be reversed for a given
- * connection.
- */
-
 void
 isc_nm_settimeouts(isc_nm_t *mgr, uint32_t init, uint32_t idle,
 		   uint32_t keepalive, uint32_t advertised);

lib/isc/netmgr/netmgr-int.h

@@ -1021,11 +1021,6 @@ struct isc_nmsocket {
 	 */
 	atomic_bool client;
 
-	/*%
-	 * TCPDNS socket has been set not to pipeline.
-	 */
-	atomic_bool sequential;
-
 	/*%
 	 * The socket is processing read callback, this is guard to not read
 	 * data before the readcb is back.

lib/isc/netmgr/netmgr.c

@@ -1567,7 +1567,6 @@ isc___nmsocket_init(isc_nmsocket_t *sock, isc_nm_t *mgr, isc_nmsocket_type type,
 			 sock, isc_refcount_current(&sock->references));
 
 	atomic_init(&sock->active, true);
-	atomic_init(&sock->sequential, false);
 	atomic_init(&sock->readpaused, false);
 	atomic_init(&sock->closing, false);
 	atomic_init(&sock->listening, 0);
@@ -2334,9 +2333,8 @@ processbuffer(isc_nmsocket_t *sock) {
  * If we only have an incomplete DNS message, we don't touch any
  * timers. If we do have a full message, reset the timer.
  *
- * Stop reading if this is a client socket, or if the server socket
- * has been set to sequential mode. In this case we'll be called again
- * later by isc__nm_resume_processing().
+ * Stop reading if this is a client socket.  In this case we'll be
+ * called again later by isc__nm_resume_processing().
  */
 void
 isc__nm_process_sock_buffer(isc_nmsocket_t *sock) {
@@ -2372,8 +2370,7 @@ isc__nm_process_sock_buffer(isc_nmsocket_t *sock) {
 			 */
 			isc__nmsocket_timer_stop(sock);
 
-			if (atomic_load(&sock->client) ||
-			    atomic_load(&sock->sequential)) {
+			if (atomic_load(&sock->client)) {
 				isc__nm_stop_reading(sock);
 				return;
 			}
@@ -3447,39 +3444,6 @@ isc_nm_work_offload(isc_nm_t *netmgr, isc_nm_workcb_t work_cb,
 	UV_RUNTIME_CHECK(uv_queue_work, r);
 }
 
-void
-isc_nm_sequential(isc_nmhandle_t *handle) {
-	isc_nmsocket_t *sock = NULL;
-
-	REQUIRE(VALID_NMHANDLE(handle));
-	REQUIRE(VALID_NMSOCK(handle->sock));
-
-	sock = handle->sock;
-
-	switch (sock->type) {
-	case isc_nm_tcpdnssocket:
-	case isc_nm_tlsdnssocket:
-		break;
-	case isc_nm_httpsocket:
-		return;
-	default:
-		INSIST(0);
-		ISC_UNREACHABLE();
-	}
-
-	/*
-	 * We don't want pipelining on this connection. That means
-	 * that we need to pause after reading each request, and
-	 * resume only after the request has been processed. This
-	 * is done in isc__nm_resume_processing(), which is the
-	 * socket's closehandle_cb callback, called whenever a handle
-	 * is released.
-	 */
-	isc__nmsocket_timer_stop(sock);
-	isc__nm_stop_reading(sock);
-	atomic_store(&sock->sequential, true);
-}
-
 void
 isc_nm_bad_request(isc_nmhandle_t *handle) {
 	isc_nmsocket_t *sock = NULL;

lib/ns/client.c

@@ -1915,18 +1915,6 @@ ns__client_request(isc_nmhandle_t *handle, isc_result_t eresult,
 		return;
 	}
 
-	/*
-	 * Disable pipelined TCP query processing if necessary.
-	 */
-	if (TCP_CLIENT(client) &&
-	    (client->message->opcode != dns_opcode_query ||
-	     (client->sctx->keepresporder != NULL &&
-	      dns_acl_allowed(&netaddr, NULL, client->sctx->keepresporder,
-			      env))))
-	{
-		isc_nm_sequential(handle);
-	}
-
 	dns_opcodestats_increment(client->sctx->opcodestats,
 				  client->message->opcode);
 	switch (client->message->opcode) {

lib/ns/include/ns/server.h

@@ -90,7 +90,6 @@ struct ns_server {
 	uint32_t options;
 
 	dns_acl_t	  *blackholeacl;
-	dns_acl_t	  *keepresporder;
 	uint16_t       udpsize;
 	uint16_t       transfer_tcp_message_size;
 	bool	       interface_auto;

lib/ns/server.c

@@ -158,9 +158,6 @@ ns_server_detach(ns_server_t **sctxp) {
 		if (sctx->blackholeacl != NULL) {
 			dns_acl_detach(&sctx->blackholeacl);
 		}
-		if (sctx->keepresporder != NULL) {
-			dns_acl_detach(&sctx->keepresporder);
-		}
 		if (sctx->tkeyctx != NULL) {
 			dns_tkeyctx_destroy(&sctx->tkeyctx);
 		}