diff --git a/lib/thread.c b/lib/thread.c
index 71d7798af5..5dbba6363d 100644
--- a/lib/thread.c
+++ b/lib/thread.c
@@ -922,10 +922,10 @@ done:
 }
 
 /* Add new read thread. */
-struct thread *_thread_add_read_write(const struct xref_threadsched *xref,
-				      struct thread_master *m,
-				      int (*func)(struct thread *),
-				      void *arg, int fd, struct thread **t_ptr)
+void _thread_add_read_write(const struct xref_threadsched *xref,
+			    struct thread_master *m,
+			    int (*func)(struct thread *), void *arg, int fd,
+			    struct thread **t_ptr)
 {
 	int dir = xref->thread_type;
 	struct thread *thread = NULL;
@@ -1000,15 +1000,13 @@ struct thread *_thread_add_read_write(const struct xref_threadsched *xref,
 
 		AWAKEN(m);
 	}
-
-	return thread;
 }
 
-static struct thread *
-_thread_add_timer_timeval(const struct xref_threadsched *xref,
-			  struct thread_master *m, int (*func)(struct thread *),
-			  void *arg, struct timeval *time_relative,
-			  struct thread **t_ptr)
+static void _thread_add_timer_timeval(const struct xref_threadsched *xref,
+				      struct thread_master *m,
+				      int (*func)(struct thread *), void *arg,
+				      struct timeval *time_relative,
+				      struct thread **t_ptr)
 {
 	struct thread *thread;
 	struct timeval t;
@@ -1028,7 +1026,7 @@ _thread_add_timer_timeval(const struct xref_threadsched *xref,
 	frr_with_mutex(&m->mtx) {
 		if (t_ptr && *t_ptr)
 			/* thread is already scheduled; don't reschedule */
-			return NULL;
+			return;
 
 		thread = thread_get(m, THREAD_TIMER, func, arg, xref);
 
@@ -1048,16 +1046,13 @@ _thread_add_timer_timeval(const struct xref_threadsched *xref,
 		if (thread_timer_list_first(&m->timer) == thread)
 			AWAKEN(m);
 	}
-
-	return thread;
 }
 
 
 /* Add timer event thread. */
-struct thread *_thread_add_timer(const struct xref_threadsched *xref,
-				 struct thread_master *m,
-				 int (*func)(struct thread *),
-				 void *arg, long timer, struct thread **t_ptr)
+void _thread_add_timer(const struct xref_threadsched *xref,
+		       struct thread_master *m, int (*func)(struct thread *),
+		       void *arg, long timer, struct thread **t_ptr)
 {
 	struct timeval trel;
 
@@ -1066,15 +1061,14 @@ struct thread *_thread_add_timer(const struct xref_threadsched *xref,
 	trel.tv_sec = timer;
 	trel.tv_usec = 0;
 
-	return _thread_add_timer_timeval(xref, m, func, arg, &trel, t_ptr);
+	_thread_add_timer_timeval(xref, m, func, arg, &trel, t_ptr);
 }
 
 /* Add timer event thread with "millisecond" resolution */
-struct thread *_thread_add_timer_msec(const struct xref_threadsched *xref,
-				      struct thread_master *m,
-				      int (*func)(struct thread *),
-				      void *arg, long timer,
-				      struct thread **t_ptr)
+void _thread_add_timer_msec(const struct xref_threadsched *xref,
+			    struct thread_master *m,
+			    int (*func)(struct thread *), void *arg, long timer,
+			    struct thread **t_ptr)
 {
 	struct timeval trel;
 
@@ -1083,24 +1077,21 @@ struct thread *_thread_add_timer_msec(const struct xref_threadsched *xref,
 	trel.tv_sec = timer / 1000;
 	trel.tv_usec = 1000 * (timer % 1000);
 
-	return _thread_add_timer_timeval(xref, m, func, arg, &trel, t_ptr);
+	_thread_add_timer_timeval(xref, m, func, arg, &trel, t_ptr);
 }
 
 /* Add timer event thread with "timeval" resolution */
-struct thread *_thread_add_timer_tv(const struct xref_threadsched *xref,
-				    struct thread_master *m,
-				    int (*func)(struct thread *),
-				    void *arg, struct timeval *tv,
-				    struct thread **t_ptr)
+void _thread_add_timer_tv(const struct xref_threadsched *xref,
+			  struct thread_master *m, int (*func)(struct thread *),
+			  void *arg, struct timeval *tv, struct thread **t_ptr)
 {
-	return _thread_add_timer_timeval(xref, m, func, arg, tv, t_ptr);
+	_thread_add_timer_timeval(xref, m, func, arg, tv, t_ptr);
 }
 
 /* Add simple event thread. */
-struct thread *_thread_add_event(const struct xref_threadsched *xref,
-				 struct thread_master *m,
-				 int (*func)(struct thread *),
-				 void *arg, int val, struct thread **t_ptr)
+void _thread_add_event(const struct xref_threadsched *xref,
+		       struct thread_master *m, int (*func)(struct thread *),
+		       void *arg, int val, struct thread **t_ptr)
 {
 	struct thread *thread = NULL;
 
@@ -1128,8 +1119,6 @@ struct thread *_thread_add_event(const struct xref_threadsched *xref,
 
 		AWAKEN(m);
 	}
-
-	return thread;
 }
 
 /* Thread cancellation ------------------------------------------------------ */
diff --git a/lib/thread.h b/lib/thread.h
index c5f0ffbf77..39f21da11d 100644
--- a/lib/thread.h
+++ b/lib/thread.h
@@ -219,26 +219,30 @@ void thread_master_set_name(struct thread_master *master, const char *name);
 extern void thread_master_free(struct thread_master *);
 extern void thread_master_free_unused(struct thread_master *);
 
-extern struct thread *_thread_add_read_write(
-	const struct xref_threadsched *xref, struct thread_master *master,
-	int (*fn)(struct thread *), void *arg, int fd, struct thread **tref);
+extern void _thread_add_read_write(const struct xref_threadsched *xref,
+				   struct thread_master *master,
+				   int (*fn)(struct thread *), void *arg,
+				   int fd, struct thread **tref);
 
-extern struct thread *_thread_add_timer(
-	const struct xref_threadsched *xref, struct thread_master *master,
-	int (*fn)(struct thread *), void *arg, long t, struct thread **tref);
+extern void _thread_add_timer(const struct xref_threadsched *xref,
+			      struct thread_master *master,
+			      int (*fn)(struct thread *), void *arg, long t,
+			      struct thread **tref);
 
-extern struct thread *_thread_add_timer_msec(
-	const struct xref_threadsched *xref, struct thread_master *master,
-	int (*fn)(struct thread *), void *arg, long t, struct thread **tref);
+extern void _thread_add_timer_msec(const struct xref_threadsched *xref,
+				   struct thread_master *master,
+				   int (*fn)(struct thread *), void *arg,
+				   long t, struct thread **tref);
 
-extern struct thread *_thread_add_timer_tv(
-	const struct xref_threadsched *xref, struct thread_master *master,
-	int (*fn)(struct thread *), void *arg, struct timeval *tv,
-	struct thread **tref);
+extern void _thread_add_timer_tv(const struct xref_threadsched *xref,
+				 struct thread_master *master,
+				 int (*fn)(struct thread *), void *arg,
+				 struct timeval *tv, struct thread **tref);
 
-extern struct thread *_thread_add_event(
-	const struct xref_threadsched *xref, struct thread_master *master,
-	int (*fn)(struct thread *), void *arg, int val, struct thread **tref);
+extern void _thread_add_event(const struct xref_threadsched *xref,
+			      struct thread_master *master,
+			      int (*fn)(struct thread *), void *arg, int val,
+			      struct thread **tref);
 
 extern void _thread_execute(const struct xref_threadsched *xref,
 			    struct thread_master *master,
diff --git a/lib/vty.c b/lib/vty.c
index df26cae541..5a03514be4 100644
--- a/lib/vty.c
+++ b/lib/vty.c
@@ -2697,19 +2697,21 @@ static struct thread_master *vty_master;
 
 static void vty_event_serv(enum event event, int sock)
 {
-	struct thread *vty_serv_thread = NULL;
+	struct thread **vty_serv_thread_ptr = NULL;
 
 	switch (event) {
 	case VTY_SERV:
-		vty_serv_thread = thread_add_read(vty_master, vty_accept,
-						  NULL, sock, NULL);
-		vector_set_index(Vvty_serv_thread, sock, vty_serv_thread);
+		vty_serv_thread_ptr = (struct thread **)vector_get_index(
+			Vvty_serv_thread, sock);
+		thread_add_read(vty_master, vty_accept, NULL, sock,
+				vty_serv_thread_ptr);
 		break;
 #ifdef VTYSH
 	case VTYSH_SERV:
-		vty_serv_thread = thread_add_read(vty_master, vtysh_accept,
-						  NULL, sock, NULL);
-		vector_set_index(Vvty_serv_thread, sock, vty_serv_thread);
+		vty_serv_thread_ptr = (struct thread **)vector_get_index(
+			Vvty_serv_thread, sock);
+		thread_add_read(vty_master, vtysh_accept, NULL, sock,
+				vty_serv_thread_ptr);
 		break;
 #endif /* VTYSH */
 	default:
diff --git a/ospfd/ospf_lsa.c b/ospfd/ospf_lsa.c
index cc1b2919c0..10541b09bb 100644
--- a/ospfd/ospf_lsa.c
+++ b/ospfd/ospf_lsa.c
@@ -2480,10 +2480,6 @@ ospf_router_lsa_install(struct ospf *ospf, struct ospf_lsa *new, int rt_recalc)
 	return new;
 }
 
-#define OSPF_INTERFACE_TIMER_ON(T, F, V)                                       \
-	if (!(T))                                                              \
-	(T) = thread_add_timer(master, (F), oi, (V))
-
 /* Install network-LSA to an area. */
 static struct ospf_lsa *ospf_network_lsa_install(struct ospf *ospf,
 						 struct ospf_interface *oi,
diff --git a/ospfd/ospf_lsa.h b/ospfd/ospf_lsa.h
index 5dcd072774..2e648b3354 100644
--- a/ospfd/ospf_lsa.h
+++ b/ospfd/ospf_lsa.h
@@ -223,10 +223,6 @@ struct as_external_lsa {
 
 #define OSPF_LSA_UPDATE_DELAY		2
 
-#define OSPF_LSA_UPDATE_TIMER_ON(T, F)                                         \
-	if (!(T))                                                              \
-	(T) = thread_add_timer(master, (F), 0, 2)
-
 #define CHECK_LSA_TYPE_1_TO_5_OR_7(type)                                       \
 	((type == OSPF_ROUTER_LSA) || (type == OSPF_NETWORK_LSA)               \
 	 || (type == OSPF_SUMMARY_LSA) || (type == OSPF_ASBR_SUMMARY_LSA)      \
diff --git a/zebra/zebra_netns_notify.c b/zebra/zebra_netns_notify.c
index 61f97ce6a9..2d25801590 100644
--- a/zebra/zebra_netns_notify.c
+++ b/zebra/zebra_netns_notify.c
@@ -249,8 +249,8 @@ static int zebra_ns_notify_read(struct thread *t)
 	char buf[BUFSIZ];
 	ssize_t len;
 
-	zebra_netns_notify_current = thread_add_read(
-		zrouter.master, zebra_ns_notify_read, NULL, fd_monitor, NULL);
+	thread_add_read(zrouter.master, zebra_ns_notify_read, NULL, fd_monitor,
+			&zebra_netns_notify_current);
 	len = read(fd_monitor, buf, sizeof(buf));
 	if (len < 0) {
 		flog_err_sys(EC_ZEBRA_NS_NOTIFY_READ,
@@ -359,8 +359,8 @@ void zebra_ns_notify_init(void)
 			     "NS notify watch: failed to add watch (%s)",
 			     safe_strerror(errno));
 	}
-	zebra_netns_notify_current = thread_add_read(
-		zrouter.master, zebra_ns_notify_read, NULL, fd_monitor, NULL);
+	thread_add_read(zrouter.master, zebra_ns_notify_read, NULL, fd_monitor,
+			&zebra_netns_notify_current);
 }
 
 void zebra_ns_notify_close(void)