From: Ondřej Surý <ondrej@isc.org>
Date: Tue, 16 Dec 2025 10:43:34 +0000 (+0100)
Subject: Cleanup the unused members of dns_slabheader_t
X-Git-Tag: v9.21.19~22^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aaf3454079529a53211006d4f434a5103f969f36;p=thirdparty%2Fbind9.git

Cleanup the unused members of dns_slabheader_t

After the rdataslab -> rdataslab,rdatavec split, there were couple of
unused struct members.  Remove all the unused members, reorder the
members to eliminate the padding holes and thus reduce the
dns_slabheader_t and dns_slabtop_t structure sizes.
---

diff --git a/lib/dns/include/dns/rdataslab.h b/lib/dns/include/dns/rdataslab.h
index a2e33ad998f..0a19338dc08 100644
--- a/lib/dns/include/dns/rdataslab.h
+++ b/lib/dns/include/dns/rdataslab.h
@@ -77,14 +77,13 @@ struct dns_slabtop {
 	struct cds_list_head types_link;
 	struct cds_list_head headers;
 
-	dns_typepair_t typepair;
-
 	dns_slabtop_t *related;
 
-	/*% Used for SIEVE-LRU (cache) and changed_list (zone) */
-	ISC_LINK(struct dns_slabtop) link;
-	/*% Used for SIEVE-LRU */
+	dns_typepair_t typepair;
+
+	/*% Used for SIEVE-LRU (cache) */
 	bool visited;
+	ISC_LINK(struct dns_slabtop) link;
 };
 
 struct dns_slabheader {
@@ -94,21 +93,15 @@ struct dns_slabheader {
 	/*%
 	 * Locked by the owning node's lock.
 	 */
-	uint32_t serial;
-	union {
-		isc_stdtime_t expire;
-		dns_ttl_t     ttl;
-	};
+	isc_stdtime_t  expire;
 	dns_typepair_t typepair;
 
-	/* resigning (zone) and TTL-cleaning (cache) */
-	uint16_t      resign_lsb : 1;
-	isc_stdtime_t resign;
-	isc_heap_t   *heap;
-	unsigned int  heap_index;
+	/* TTL-cleaning (cache) */
+	unsigned int heap_index;
+	isc_heap_t  *heap;
 
 	/* Used for stale refresh */
-	_Atomic(uint32_t) last_refresh_fail_ts;
+	_Atomic(isc_stdtime_t) last_refresh_fail_ts;
 
 	dns_slabheader_proof_t *noqname;
 	dns_slabheader_proof_t *closest;
diff --git a/lib/dns/rdataslab.c b/lib/dns/rdataslab.c
index 6850fd1fb73..d73e3ce2733 100644
--- a/lib/dns/rdataslab.c
+++ b/lib/dns/rdataslab.c
@@ -110,7 +110,7 @@ newslab(dns_rdataset_t *rdataset, isc_mem_t *mctx, isc_region_t *region,
 	*header = (dns_slabheader_t){
 		.headers_link = CDS_LIST_HEAD_INIT(header->headers_link),
 		.trust = rdataset->trust,
-		.ttl = rdataset->ttl,
+		.expire = rdataset->ttl,
 		.dirtylink = ISC_LINK_INITIALIZER,
 	};