Merge branch 'ondrej/various-rbtdb-fixes' into 'main'

Various rbtdb fixes and optimizations

See merge request isc-projects/bind9!8675

CHANGES

@@ -1,3 +1,7 @@
+6338.	[func]		Optimize slabheader placement, so the infrastructure
+			records are put in the beginning of the slabheader
+			linked list. [GL !8675]
+
 6337.	[bug]		Nsupdate could assert while shutting down. [GL #4529]
 
 6336.	[func]		Expose the zones with the 'first refresh' flag set in

bin/tests/system/resolver/tests.sh

@@ -482,10 +482,10 @@ dig_with_opts @10.53.0.5 fetchall.tld any >dig.out.2.${n} || ret=1
 ttl2=$(awk '/"A" "short" "ttl"/ { print $2 }' dig.out.2.${n})
 sleep 1
 # check that prefetch occurred;
-# note that only one record is prefetched, which is the TXT record in this case,
+# note that only one record is prefetched, which is the AAAA record in this case,
 # because of the order of the records in the cache
 dig_with_opts @10.53.0.5 fetchall.tld any >dig.out.3.${n} || ret=1
-ttl3=$(awk '/"A" "short" "ttl"/ { print $2 }' dig.out.3.${n})
+ttl3=$(awk '/::1/ { print $2 }' dig.out.3.${n})
 test "${ttl3:-0}" -gt "${ttl2:-1}" || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=$((status + ret))

lib/dns/rbt-cachedb.c

@@ -909,13 +909,18 @@ cache_find(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
 				 */
 				found = header;
 				if (header->type == dns_rdatatype_cname &&
-				    cname_ok && cnamesig != NULL)
+				    cname_ok)
 				{
 					/*
 					 * If we've already got the
 					 * CNAME RRSIG, use it.
 					 */
+					if (cnamesig != NULL) {
 						foundsig = cnamesig;
+					} else {
+						sigtype =
+							RBTDB_RDATATYPE_SIGCNAME;
+					}
 				}
 			} else if (header->type == sigtype) {
 				/*

lib/dns/rbtdb.c

@@ -335,6 +335,30 @@ dns__rbtdb_setttl(dns_slabheader_t *header, dns_ttl_t newttl) {
 	}
 }
 
+static bool
+prio_type(dns_typepair_t type) {
+	switch (type) {
+	case dns_rdatatype_soa:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_soa):
+	case dns_rdatatype_a:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_a):
+	case dns_rdatatype_aaaa:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_aaaa):
+	case dns_rdatatype_nsec:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_nsec):
+	case dns_rdatatype_nsec3:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_nsec3):
+	case dns_rdatatype_ns:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_ns):
+	case dns_rdatatype_ds:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_ds):
+	case dns_rdatatype_cname:
+	case DNS_TYPEPAIR_VALUE(dns_rdatatype_rrsig, dns_rdatatype_cname):
+		return (true);
+	}
+	return (false);
+}
+
 /*%
  * These functions allow the heap code to rank the priority of each
  * element.  It returns true if v1 happens "sooner" than v2.
@@ -2367,7 +2391,7 @@ dns__rbtdb_allrdatasets(dns_db_t *db, dns_dbnode_t *node,
 static bool
 cname_and_other_data(dns_rbtnode_t *node, uint32_t serial) {
 	dns_slabheader_t *header = NULL, *header_next = NULL;
-	bool cname, other_data;
+	bool cname = false, other_data = false;
 	dns_rdatatype_t rdtype;
 
 	/*
@@ -2377,10 +2401,16 @@ cname_and_other_data(dns_rbtnode_t *node, uint32_t serial) {
 	/*
 	 * Look for CNAME and "other data" rdatasets active in our version.
 	 */
-	cname = false;
-	other_data = false;
 	for (header = node->data; header != NULL; header = header_next) {
 		header_next = header->next;
+		if (!prio_type(header->type)) {
+			/*
+			 * CNAME is in the priority list, so if we are done
+			 * with the priority list, we know there will not be
+			 * CNAME, so we are safe to skip the rest of the types.
+			 */
+			return (false);
+		}
 		if (header->type == dns_rdatatype_cname) {
 			/*
 			 * Look for an active extant CNAME.
@@ -2440,11 +2470,10 @@ cname_and_other_data(dns_rbtnode_t *node, uint32_t serial) {
 				}
 			}
 		}
-	}
-
 		if (cname && other_data) {
 			return (true);
 		}
+	}
 
 	return (false);
 }
@@ -2482,6 +2511,7 @@ dns__rbtdb_add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode,
 	rbtdb_changed_t *changed = NULL;
 	dns_slabheader_t *topheader = NULL, *topheader_prev = NULL;
 	dns_slabheader_t *header = NULL, *sigheader = NULL;
+	dns_slabheader_t *prioheader = NULL;
 	unsigned char *merged = NULL;
 	isc_result_t result;
 	bool header_nx;
@@ -2615,6 +2645,9 @@ dns__rbtdb_add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode,
 	for (topheader = rbtnode->data; topheader != NULL;
 	     topheader = topheader->next)
 	{
+		if (prio_type(topheader->type)) {
+			prioheader = topheader;
+		}
 		if (topheader->type == newheader->type ||
 		    topheader->type == negtype)
 		{
@@ -2999,9 +3032,21 @@ find_header:
 			/*
 			 * No rdatasets of the given type exist at the node.
 			 */
+			INSIST(newheader->down == NULL);
+
+			if (prio_type(newheader->type)) {
+				/* This is a priority type, prepend it */
 				newheader->next = rbtnode->data;
-			newheader->down = NULL;
 				rbtnode->data = newheader;
+			} else if (prioheader != NULL) {
+				/* Append after the priority headers */
+				newheader->next = prioheader->next;
+				prioheader->next = newheader;
+			} else {
+				/* There were no priority headers */
+				newheader->next = rbtnode->data;
+				rbtnode->data = newheader;
+			}
 		}
 	}
 

tests/bench/load-names.c

@@ -374,7 +374,7 @@ add_qp(void *qp, size_t count) {
 
 static void
 sqz_qp(void *qp) {
-	dns_qp_compact(qp, DNS_QPGC_ALL);
+	dns_qp_compact(qp, DNS_QPGC_MAYBE);
 }
 
 static isc_result_t