eigrpd: Ensure better `struct thread *` semantics

1) Do not explicitly set the thread pointer to NULL.
FRR should only ever use the appropriate THREAD_ON/THREAD_OFF
semantics.  This is espacially true for the functions we
end up calling the thread for.

2) Fix mixup of `struct eigrp_interface` and `struct eigrp`
usage of the same thread pointer.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

6 files changed, 2 insertions, 17 deletions

diff --git a/eigrpd/eigrp_filter.c b/eigrpd/eigrp_filter.c
index 8f80b78d2..bb0cf51bd 100644
--- a/eigrpd/eigrp_filter.c
+++ b/eigrpd/eigrp_filter.c
@@ -203,9 +203,8 @@ void eigrp_distribute_update(struct distribute_ctx *ctx,
 	/* Cancel GR scheduled */
 	thread_cancel(&(ei->t_distribute));
 	/* schedule Graceful restart for interface in 10sec */
-	e->t_distribute = NULL;
 	thread_add_timer(master, eigrp_distribute_timer_interface, ei, 10,
-			 &e->t_distribute);
+			 &ei->t_distribute);
 }
 
 /*
@@ -263,7 +262,6 @@ int eigrp_distribute_timer_process(struct thread *thread)
 	struct eigrp *eigrp;
 
 	eigrp = THREAD_ARG(thread);
-	eigrp->t_distribute = NULL;
 
 	/* execute GR for whole process */
 	eigrp_update_send_process_GR(eigrp, EIGRP_GR_FILTER, NULL);
diff --git a/eigrpd/eigrp_hello.c b/eigrpd/eigrp_hello.c
index e3680b31a..2ff8fc5f3 100644
--- a/eigrpd/eigrp_hello.c
+++ b/eigrpd/eigrp_hello.c
@@ -86,7 +86,6 @@ int eigrp_hello_timer(struct thread *thread)
 	struct eigrp_interface *ei;
 
 	ei = THREAD_ARG(thread);
-	ei->t_hello = NULL;
 
 	if (IS_DEBUG_EIGRP(0, TIMERS))
 		zlog_debug("Start Hello Timer (%s) Expire [%u]", IF_NAME(ei),
@@ -96,7 +95,6 @@ int eigrp_hello_timer(struct thread *thread)
 	eigrp_hello_send(ei, EIGRP_HELLO_NORMAL, NULL);
 
 	/* Hello timer set. */
-	ei->t_hello = NULL;
 	thread_add_timer(master, eigrp_hello_timer, ei, ei->params.v_hello,
 			 &ei->t_hello);
 
diff --git a/eigrpd/eigrp_interface.c b/eigrpd/eigrp_interface.c
index 02e943043..28987b4af 100644
--- a/eigrpd/eigrp_interface.c
+++ b/eigrpd/eigrp_interface.c
@@ -265,7 +265,7 @@ int eigrp_if_up(struct eigrp_interface *ei)
 	/* Set multicast memberships appropriately for new state. */
 	eigrp_if_set_multicast(ei);
 
-	thread_add_event(master, eigrp_hello_timer, ei, (1), NULL);
+	thread_add_event(master, eigrp_hello_timer, ei, (1), &ei->t_hello);
 
 	/*Prepare metrics*/
 	metric.bandwidth = eigrp_bandwidth_to_scaled(ei->params.bandwidth);
diff --git a/eigrpd/eigrp_packet.c b/eigrpd/eigrp_packet.c
index 39e384c12..529d94567 100644
--- a/eigrpd/eigrp_packet.c
+++ b/eigrpd/eigrp_packet.c
@@ -340,8 +340,6 @@ int eigrp_write(struct thread *thread)
 #endif /* WANT_EIGRP_WRITE_FRAGMENT */
 #define EIGRP_WRITE_IPHL_SHIFT 2
 
-	eigrp->t_write = NULL;
-
 	node = listhead(eigrp->oi_write_q);
 	assert(node);
 	ei = listgetdata(node);
@@ -470,7 +468,6 @@ out:
 
 	/* If packets still remain in queue, call write thread. */
 	if (!list_isempty(eigrp->oi_write_q)) {
-		eigrp->t_write = NULL;
 		thread_add_write(master, eigrp_write, eigrp, eigrp->fd,
 				 &eigrp->t_write);
 	}
@@ -497,7 +494,6 @@ int eigrp_read(struct thread *thread)
 	eigrp = THREAD_ARG(thread);
 
 	/* prepare for next packet. */
-	eigrp->t_read = NULL;
 	thread_add_read(master, eigrp_read, eigrp, eigrp->fd, &eigrp->t_read);
 
 	stream_reset(eigrp->ibuf);
@@ -1013,7 +1009,6 @@ int eigrp_unack_packet_retrans(struct thread *thread)
 			return eigrp_retrans_count_exceeded(ep, nbr);
 
 		/*Start retransmission timer*/
-		ep->t_retrans_timer = NULL;
 		thread_add_timer(master, eigrp_unack_packet_retrans, nbr,
 				 EIGRP_PACKET_RETRANS_TIME,
 				 &ep->t_retrans_timer);
@@ -1049,7 +1044,6 @@ int eigrp_unack_multicast_packet_retrans(struct thread *thread)
 			return eigrp_retrans_count_exceeded(ep, nbr);
 
 		/*Start retransmission timer*/
-		ep->t_retrans_timer = NULL;
 		thread_add_timer(master, eigrp_unack_multicast_packet_retrans,
 				 nbr, EIGRP_PACKET_RETRANS_TIME,
 				 &ep->t_retrans_timer);
diff --git a/eigrpd/eigrp_update.c b/eigrpd/eigrp_update.c
index 0dc509706..8a9eea8a7 100644
--- a/eigrpd/eigrp_update.c
+++ b/eigrpd/eigrp_update.c
@@ -917,12 +917,10 @@ int eigrp_update_send_GR_thread(struct thread *thread)
 	/* get argument from thread */
 	nbr = THREAD_ARG(thread);
 	/* remove this thread pointer */
-	nbr->t_nbr_send_gr = NULL;
 
 	/* if there is packet waiting in queue,
 	 * schedule this thread again with small delay */
 	if (nbr->retrans_queue->count > 0) {
-		nbr->t_nbr_send_gr = NULL;
 		thread_add_timer_msec(master, eigrp_update_send_GR_thread, nbr,
 				      10, &nbr->t_nbr_send_gr);
 		return 0;
@@ -934,7 +932,6 @@ int eigrp_update_send_GR_thread(struct thread *thread)
 	/* if it wasn't last chunk, schedule this thread again */
 	if (nbr->nbr_gr_packet_type != EIGRP_PACKET_PART_LAST) {
 		thread_execute(master, eigrp_update_send_GR_thread, nbr, 0);
-		nbr->t_nbr_send_gr = NULL;
 	}
 
 	return 0;
@@ -1003,7 +1000,6 @@ void eigrp_update_send_GR(struct eigrp_neighbor *nbr, enum GR_type gr_type,
 	nbr->nbr_gr_packet_type = EIGRP_PACKET_PART_FIRST;
 	/* execute packet sending in thread */
 	thread_execute(master, eigrp_update_send_GR_thread, nbr, 0);
-	nbr->t_nbr_send_gr = NULL;
 }
 
 /**
diff --git a/eigrpd/eigrpd.c b/eigrpd/eigrpd.c
index 103015490..84d4f6aee 100644
--- a/eigrpd/eigrpd.c
+++ b/eigrpd/eigrpd.c
@@ -171,7 +171,6 @@ static struct eigrp *eigrp_new(uint16_t as, vrf_id_t vrf_id)
 
 	eigrp->ibuf = stream_new(EIGRP_PACKET_MAX_LEN + 1);
 
-	eigrp->t_read = NULL;
 	thread_add_read(master, eigrp_read, eigrp, eigrp->fd, &eigrp->t_read);
 	eigrp->oi_write_q = list_new();