From: Libor Peltan <libor.peltan@nic.cz>
Date: Fri, 14 Nov 2025 08:02:51 +0000 (+0100)
Subject: zone/timers: only write to timerDB if modified
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9cff75c48b0a9c9fa52c62384f1bc097db09de10;p=thirdparty%2Fknot-dns.git

zone/timers: only write to timerDB if modified
---

diff --git a/src/knot/dnssec/zone-sign.c b/src/knot/dnssec/zone-sign.c
index 856c089cf6..7308ec4f9d 100644
--- a/src/knot/dnssec/zone-sign.c
+++ b/src/knot/dnssec/zone-sign.c
@@ -887,6 +887,7 @@ int knot_zone_sign_update_dnskeys(zone_update_t *update,
 	if (dnssec_ctx->policy->ds_push && node_rrtype_exists(ch.add->apex, KNOT_RRTYPE_CDS)) {
 		// there is indeed a change to CDS
 		update->zone->timers->next_ds_push = time(NULL) + dnssec_ctx->policy->propagation_delay;
+		update->zone->timers->flags |= TIMERS_MODIFIED;
 		zone_events_schedule_at(update->zone, ZONE_EVENT_DS_PUSH, update->zone->timers->next_ds_push);
 	}
 
diff --git a/src/knot/events/handlers/dnssec.c b/src/knot/events/handlers/dnssec.c
index 0150bdd3b6..d0367a76a6 100644
--- a/src/knot/events/handlers/dnssec.c
+++ b/src/knot/events/handlers/dnssec.c
@@ -41,6 +41,7 @@ void event_dnssec_reschedule(conf_t *conf, zone_t *zone,
 
 	if (refresh->plan_ds_check) {
 		zone->timers->next_ds_check = now;
+		zone->timers->flags |= TIMERS_MODIFIED;
 	}
 
 	unsigned jitter = dnskey_sync_jitter(conf, zone);
diff --git a/src/knot/events/handlers/ds_check.c b/src/knot/events/handlers/ds_check.c
index f4f8cae2b3..eaf44f5b9e 100644
--- a/src/knot/events/handlers/ds_check.c
+++ b/src/knot/events/handlers/ds_check.c
@@ -25,6 +25,8 @@ int event_ds_check(conf_t *conf, zone_t *zone)
 	                           conf->cache.srv_tcp_remote_io_timeout);
 
 	zone->timers->next_ds_check = 0;
+	zone->timers->flags |= TIMERS_MODIFIED;
+
 	switch (ret) {
 	case KNOT_NO_READY_KEY:
 		break;
diff --git a/src/knot/events/handlers/ds_push.c b/src/knot/events/handlers/ds_push.c
index deb6392050..1f59d2fddc 100644
--- a/src/knot/events/handlers/ds_push.c
+++ b/src/knot/events/handlers/ds_push.c
@@ -249,6 +249,7 @@ int event_ds_push(conf_t *conf, zone_t *zone)
 			zone_events_schedule_at(zone, ZONE_EVENT_DS_PUSH, next_push);
 			zone->timers->next_ds_push = next_push;
 		}
+		zone->timers->flags |= TIMERS_MODIFIED;
 
 		conf_mix_iter_next(&iter);
 	}
diff --git a/src/knot/events/handlers/notify.c b/src/knot/events/handlers/notify.c
index 1cb788cb53..7728dc23a0 100644
--- a/src/knot/events/handlers/notify.c
+++ b/src/knot/events/handlers/notify.c
@@ -112,7 +112,7 @@ static int send_notify(conf_t *conf, zone_t *zone, const knot_rrset_t *soa,
 		               requestor.layer.flags,
 		               "%sserial %u", log_retry, knot_soa_serial(soa->rrs.rdata));
 		zone->timers->last_notified_serial = knot_soa_serial(soa->rrs.rdata);
-		zone->timers->flags |= LAST_NOTIFIED_SERIAL_VALID;
+		zone->timers->flags |= LAST_NOTIFIED_SERIAL_VALID | TIMERS_MODIFIED;
 	} else if (knot_pkt_ext_rcode(req->resp) == 0) {
 		NOTIFY_OUT_LOG(LOG_WARNING, zone->name, slave,
 		               requestor.layer.flags,
diff --git a/src/knot/events/handlers/refresh.c b/src/knot/events/handlers/refresh.c
index fc5f2fbf19..46f7834564 100644
--- a/src/knot/events/handlers/refresh.c
+++ b/src/knot/events/handlers/refresh.c
@@ -219,7 +219,7 @@ static void finalize_timers_base(struct refresh_data *data, bool also_expire)
 	limit_timer(conf, zone->name, &soa_refresh, "refresh",
 	            C_REFRESH_MIN_INTERVAL, C_REFRESH_MAX_INTERVAL);
 	zone->timers->next_refresh = now + soa_refresh;
-	zone->timers->flags |= LAST_REFRESH_OK;
+	zone->timers->flags |= LAST_REFRESH_OK | TIMERS_MODIFIED;
 
 	if (zone->is_catalog_flag) {
 		// It's already zero in most cases.
@@ -1083,6 +1083,7 @@ static bool wait4pinned_master(struct refresh_data *data)
 	// Starting countdown for master transition.
 	if (data->zone->timers->master_pin_hit == 0) {
 		data->zone->timers->master_pin_hit = now;
+		data->zone->timers->flags |= TIMERS_MODIFIED;
 		zone_events_schedule_at(data->zone, ZONE_EVENT_REFRESH, now + data->fallback->pin_tol);
 	// Switch to a new master.
 	} else if (data->zone->timers->master_pin_hit + data->fallback->pin_tol <= now) {
@@ -1507,6 +1508,7 @@ int event_refresh(conf_t *conf, zone_t *zone)
 		time_t now = time(NULL);
 		zone->timers->next_refresh = now + next;
 		zone->timers->flags &= ~LAST_REFRESH_OK;
+		zone->timers->flags |= TIMERS_MODIFIED;
 
 		char time_str[64] = { 0 };
 		struct tm time_gm = { 0 };
diff --git a/src/knot/zone/backup.c b/src/knot/zone/backup.c
index 8ffe1441cb..73ec28c50f 100644
--- a/src/knot/zone/backup.c
+++ b/src/knot/zone/backup.c
@@ -498,6 +498,7 @@ int zone_backup(conf_t *conf, zone_t *zone)
 			zone_timers_sanitize(conf, zone);
 			zone->zonefile.bootstrap_cnt = 0;
 		} else {
+			zone->timers->flags |= TIMERS_MODIFIED; // otherwise the write is skipped!
 			ret = zone_timers_write(&ctx->bck_timer_db, zone->name, zone->timers);
 		}
 		if (ret != KNOT_EOK) {
diff --git a/src/knot/zone/timers.c b/src/knot/zone/timers.c
index 4e591ee968..e920f11d12 100644
--- a/src/knot/zone/timers.c
+++ b/src/knot/zone/timers.c
@@ -117,8 +117,11 @@ static int deserialize_timers(zone_timers_t *timers_ptr,
 }
 
 static void txn_write_timers(knot_lmdb_txn_t *txn, const knot_dname_t *zone,
-                             const zone_timers_t *timers)
+                             zone_timers_t *timers)
 {
+	if (!(timers->flags & TIMERS_MODIFIED)) { // TODO move this conditional to txn_zone_write, as it is also in zone_timers_write. Here temporarily to avoid git conflicts.
+		return;
+	}
 	const char *format = (timers->last_master.sin6_family == AF_INET ||
 	                      timers->last_master.sin6_family == AF_INET6) ?
 	                     "TTTTTTTTTTBD" :
@@ -139,6 +142,10 @@ static void txn_write_timers(knot_lmdb_txn_t *txn, const knot_dname_t *zone,
 		TIMER_LAST_MASTER,   &timers->last_master, sizeof(timers->last_master));
 	knot_lmdb_insert(txn, &k, &v);
 	free(v.mv_data);
+
+	if (txn->ret == KNOT_EOK) {
+		timers->flags &= ~TIMERS_MODIFIED;
+	}
 }
 
 
@@ -186,10 +193,10 @@ int zone_timers_read(knot_lmdb_db_t *db, const knot_dname_t *zone,
 }
 
 int zone_timers_write(knot_lmdb_db_t *db, const knot_dname_t *zone,
-                      const zone_timers_t *timers)
+                      zone_timers_t *timers)
 {
 	int ret = knot_lmdb_open(db);
-	if (ret != KNOT_EOK) {
+	if (ret != KNOT_EOK || !(timers->flags & TIMERS_MODIFIED)) {
 		return ret;
 	}
 	knot_lmdb_txn_t txn = { 0 };
diff --git a/src/knot/zone/timers.h b/src/knot/zone/timers.h
index 17bf72e306..e992c9fde9 100644
--- a/src/knot/zone/timers.h
+++ b/src/knot/zone/timers.h
@@ -12,6 +12,7 @@
 #include "libknot/dname.h"
 #include "knot/journal/knot_lmdb.h"
 
+#define TIMERS_MODIFIED            (1 << 0)
 #define LAST_SIGNED_SERIAL_FOUND   (1 << 1)
 #define LAST_SIGNED_SERIAL_VALID   (1 << 2)
 #define LAST_NOTIFIED_SERIAL_VALID (1 << 3)
@@ -64,7 +65,7 @@ int zone_timers_read(knot_lmdb_db_t *db, const knot_dname_t *zone,
  * \return KNOT_E*
  */
 int zone_timers_write(knot_lmdb_db_t *db, const knot_dname_t *zone,
-                      const zone_timers_t *timers);
+                      zone_timers_t *timers);
 
 /*!
  * \brief Write timers for all zones.
diff --git a/src/knot/zone/zone.c b/src/knot/zone/zone.c
index 3312483af4..01e03f83d5 100644
--- a/src/knot/zone/zone.c
+++ b/src/knot/zone/zone.c
@@ -141,6 +141,7 @@ static int flush_journal(conf_t *conf, zone_t *zone, bool allow_empty_zone, bool
 flush_journal_replan:
 	/* Plan next journal flush after proper period. */
 	zone->timers->last_flush = time(NULL);
+	zone->timers->flags |= TIMERS_MODIFIED;
 	if (sync_timeout > 0) {
 		time_t next_flush = zone->timers->last_flush + sync_timeout;
 		zone_events_schedule_at(zone, ZONE_EVENT_FLUSH, (time_t)0,
@@ -309,6 +310,7 @@ int selective_zone_purge(conf_t *conf, zone_t *zone, purge_flag_t params)
 		time_t member = (zone->catalog_gen != NULL ? zone->timers->catalog_member : 0);
 		memset(zone->timers, 0, sizeof(*zone->timers));
 		zone->timers->catalog_member = member;
+		zone->timers->flags |= TIMERS_MODIFIED;
 
 		if (member) {
 			ret = zone_timers_write(&zone->server->timerdb, zone->name,
@@ -390,6 +392,7 @@ void zone_perform_expire(conf_t *conf, zone_t *zone)
 
 	zone->timers->next_expire = time(NULL);
 	zone->timers->next_refresh = zone->timers->next_expire;
+	zone->timers->flags |= TIMERS_MODIFIED;
 	replan_from_timers(conf, zone);
 }
 
@@ -599,6 +602,7 @@ void zone_set_last_master(zone_t *zone, const struct sockaddr_storage *addr)
 		memcpy(&zone->timers->last_master, addr, sizeof(zone->timers->last_master));
 	}
 	zone->timers->master_pin_hit = 0;
+	zone->timers->flags |= TIMERS_MODIFIED;
 }
 
 static void set_flag(zone_t *zone, zone_flag_t flag, bool remove)
@@ -682,6 +686,7 @@ void zone_timers_sanitize(conf_t *conf, zone_t *zone)
 	assert(zone);
 
 	time_t now = time(NULL);
+	zone_timers_t prev = *zone->timers;
 
 	// assume now if we don't know when we flushed
 	time_set_default(&zone->timers->last_flush, now);
@@ -698,6 +703,10 @@ void zone_timers_sanitize(conf_t *conf, zone_t *zone)
 		zone->timers->flags &= ~LAST_REFRESH_OK;
 		zone->timers->next_expire = 0;
 	}
+
+	if (memcmp(&prev, zone->timers, sizeof(prev)) != 0) {
+		zone->timers->flags |= TIMERS_MODIFIED;
+	}
 }
 
 int zone_timers_begin(zone_t *zone)
@@ -966,7 +975,7 @@ void zone_set_lastsigned_serial(zone_t *zone, uint32_t serial)
 {
 	bool extra_txn = (zone->control_update != NULL && zone->timers == zone->timers_static && zone_timers_begin(zone) == KNOT_EOK); // zone_update_commit() is not within a zone event in case of control_update
 	zone->timers->last_signed_serial = serial;
-	zone->timers->flags |= LAST_SIGNED_SERIAL_FOUND | LAST_SIGNED_SERIAL_VALID;
+	zone->timers->flags |= LAST_SIGNED_SERIAL_FOUND | LAST_SIGNED_SERIAL_VALID | TIMERS_MODIFIED;
 	if (extra_txn) {
 		zone_timers_commit(zone);
 	}
diff --git a/src/knot/zone/zonedb-load.c b/src/knot/zone/zonedb-load.c
index 91d137b9ff..d00f76cb35 100644
--- a/src/knot/zone/zonedb-load.c
+++ b/src/knot/zone/zonedb-load.c
@@ -146,6 +146,7 @@ static zone_t *create_zone_new(conf_t *conf, const knot_dname_t *name,
 		zone->catalog_gen = knot_dname_copy(conf_dname(&catz), NULL);
 		if (zone->timers->catalog_member == 0) {
 			zone->timers->catalog_member = time(NULL);
+			zone->timers->flags |= TIMERS_MODIFIED;
 			ret = zone_timers_write(&zone->server->timerdb, zone->name,
 			                        zone->timers);
 		}
@@ -231,6 +232,7 @@ static zone_contents_t *zone_expire(zone_t *zone, bool zonedb_cow)
 		zone_timers_begin(zone);
 		zone->timers->next_expire = time(NULL);
 		zone->timers->next_refresh = zone->timers->next_expire;
+		zone->timers->flags |= TIMERS_MODIFIED;
 		zone_timers_commit(zone);
 	}
 	return zone_switch_contents(zone, NULL);
diff --git a/tests/knot/test_zone_timers.c b/tests/knot/test_zone_timers.c
index 6fcddc18b2..e0d93f4ce0 100644
--- a/tests/knot/test_zone_timers.c
+++ b/tests/knot/test_zone_timers.c
@@ -15,7 +15,7 @@
 #include "libknot/error.h"
 
 static const zone_timers_t MOCK_TIMERS = {
-	.flags = LAST_SIGNED_SERIAL_FOUND | LAST_SIGNED_SERIAL_VALID,
+	.flags = LAST_SIGNED_SERIAL_FOUND | LAST_SIGNED_SERIAL_VALID | TIMERS_MODIFIED,
 	.last_flush     = 1474559960,
 	.next_refresh   = 1474559961,
 	.last_notified_serial = 123456,
@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 	}
 
 	const knot_dname_t *zone = (uint8_t *)"\x7""example""\x3""com";
-	struct zone_timers timers = MOCK_TIMERS;
+	struct zone_timers timers = MOCK_TIMERS, timers2 = { 0 };
 
 	// Create database
 	knot_lmdb_db_t _db = { 0 }, *db = &_db;
@@ -82,21 +82,20 @@ int main(int argc, char *argv[])
 	is_int(KNOT_EOK, ret, "zone_timers_write()");
 
 	// Read timers
-	memset(&timers, 0, sizeof(timers));
-	ret = zone_timers_read(db, zone, &timers);
+	ret = zone_timers_read(db, zone, &timers2);
 	ok(ret == KNOT_EOK, "zone_timers_read()");
-	ok(timers_eq(&timers, &MOCK_TIMERS), "inconsistent timers");
+	ok(timers_eq(&timers2, &timers), "inconsistent timers");
 
 	// Sweep none
 	ret = zone_timers_sweep(db, keep_all, NULL);
 	is_int(KNOT_EOK, ret, "zone_timers_sweep() none");
-	ret = zone_timers_read(db, zone, &timers);
+	ret = zone_timers_read(db, zone, &timers2);
 	is_int(KNOT_EOK, ret, "zone_timers_read()");
 
 	// Sweep all
 	ret = zone_timers_sweep(db, remove_all, NULL);
 	is_int(KNOT_EOK, ret, "zone_timers_sweep() all");
-	ret = zone_timers_read(db, zone, &timers);
+	ret = zone_timers_read(db, zone, &timers2);
 	is_int(KNOT_ENOENT, ret, "zone_timers_read() nonexistent");
 
 	// Clean up.