Add code for periodic maintenance

ffd/ffd.c

@@ -215,7 +215,7 @@ static void handle_tlv_hello(const ffd_tlv_hello_t *tlv_hello, size_t len, handl
 	uint16_t seqno = ntohs(tlv_hello->seqno);
 
 	if (neigh->last_hello.tv_sec) {
-		int timediff = timespec_diff(&now, &neigh->last_hello)/10;
+		int timediff = timespec_diff(&now, &neigh->last_hello);
 		uint16_t seqexp = neigh->last_seqno + (timediff - neigh->hello_interval/2)/neigh->hello_interval;
 
 		/* cast to int16_t to ensure correct handling of seqno wrapping */
@@ -268,10 +268,11 @@ static void handle_tlv_ihu(const ffd_tlv_ihu_t *tlv_ihu, size_t len, handle_tlv_
 	}
 
 	ffd_neigh_t *neigh = get_tlv_neigh(arg);
+	neigh->ihu_interval = ntohs(tlv_ihu->interval);
 	neigh->last_ihu = now;
 	neigh->txcost = ntohs(tlv_ihu->rxcost);
 
-	fprintf(stderr, "debug: accepted IHU, txcost is %u, cost is %u now.\n", neigh->txcost, ffd_neigh_get_cost(neigh));
+	fprintf(stderr, "debug: accepted IHU, txcost is %u, cost is %u now.\n", ffd_neigh_get_txcost(neigh), ffd_neigh_get_cost(neigh));
 }
 
 static void handle_tlv_node_id(const ffd_tlv_node_id_t *tlv_node_id, size_t len, handle_tlv_arg_t *arg) {
@@ -470,6 +471,19 @@ static void send_updates(void) {
 	}
 }
 
+static void maintenance(void) {
+	ffd_iface_t *iface;
+	for (iface = iface_list; iface; iface = iface->next) {
+		ffd_neigh_t *neigh;
+		for (neigh = iface->neigh_list; neigh; neigh = neigh->next) {
+			fprintf(stderr, "debug: maintenance: %02x:%02x:%02x:%02x:%02x:%02x[%s]: %u (rx %u/tx %u)\n",
+				neigh->addr.d[0], neigh->addr.d[1], neigh->addr.d[2],
+				neigh->addr.d[3], neigh->addr.d[4], neigh->addr.d[5],
+				iface->name, ffd_neigh_get_cost(neigh), ffd_neigh_get_rxcost(neigh), ffd_neigh_get_txcost(neigh));
+		}
+	}
+}
+
 int main() {
 	if (!check_config())
 		return 1;
@@ -484,34 +498,43 @@ int main() {
 
 	struct timespec next_hello = now;
 	struct timespec next_update = now;
+	struct timespec next_maintenance = now;
 
 	while (true) {
 		update_netifs();
 
 		int hello_timeout = timespec_diff(&next_hello, &now);
-		int update_timeout = timespec_diff(&next_update, &now);
-
 		if (hello_timeout <= 0) {
 			ffd_send_hellos();
 
 			add_interval(&next_hello, FFD_HELLO_INTERVAL);
-			continue;
 		}
 
+		int update_timeout = timespec_diff(&next_update, &now);
 		if (update_timeout <= 0) {
 			fprintf(stderr, "Sending periodic update.\n");
 			send_updates();
 
 			add_interval(&next_update, FFD_UPDATE_INTERVAL);
-			continue;
 		}
 
+		int maintenance_timeout = timespec_diff(&next_maintenance, &now);
+		if (maintenance_timeout <= 0) {
+			maintenance();
+
+			add_interval(&next_maintenance, FFD_MAINTENANCE_INTERVAL);
+		}
+
+		int timeout = min(min(hello_timeout, update_timeout), maintenance_timeout);
+		if (timeout <= 0)
+			continue;
+
 		struct pollfd fds[1];
 
 		fds[0].fd = sockfd;
 		fds[0].events = POLLIN;
 
-		poll(fds, 1, min(hello_timeout, update_timeout));
+		poll(fds, 1, 10*timeout);
 
 		update_time();
 

ffd/ffd.h

@@ -39,9 +39,14 @@
 
 #define FFD_HELLO_INTERVAL 400
 #define FFD_IHU_INTERVAL (3*FFD_HELLO_INTERVAL)
-
 #define FFD_UPDATE_INTERVAL 6000
 
+#define FFD_HELLO_TIMEOUT(interval) (16*(interval))
+#define FFD_IHU_TIMEOUT(interval) ((interval)*7/2)
+#define FFD_UPDATE_TIMEOUT(interval) ((interval)*7/2)
+
+#define FFD_MAINTENANCE_INTERVAL FFD_HELLO_INTERVAL
+
 
 #define FFD_UPDATE_WITH_DATA 0x01
 
@@ -94,6 +99,8 @@ typedef struct _ffd_neigh_t {
 	uint16_t hello_interval;
 	uint16_t last_seqno;
 	struct timespec last_hello;
+
+	uint16_t ihu_interval;
 	struct timespec last_ihu;
 
 	uint16_t txcost;

ffd/neigh.c

@@ -53,7 +53,7 @@ uint16_t ffd_neigh_get_rxcost(const ffd_neigh_t *neigh) {
 	if (!neigh->hello_log || !neigh->hello_interval)
 		return 0xffff;
 
-	int timediff = timespec_diff(&now, &neigh->last_hello)/10;
+	int timediff = timespec_diff(&now, &neigh->last_hello);
 	int shift = (timediff - neigh->hello_interval/2)/neigh->hello_interval;
 	int received = __builtin_popcount(neigh->hello_log << shift);
 
@@ -63,11 +63,18 @@ uint16_t ffd_neigh_get_rxcost(const ffd_neigh_t *neigh) {
 		return (0x1000/received);
 }
 
+uint16_t ffd_neigh_get_txcost(const ffd_neigh_t *neigh) {
+	if (timespec_diff(&now, &neigh->last_ihu) > FFD_IHU_TIMEOUT(neigh->ihu_interval))
+		return 0xffff;
+	else
+		return neigh->txcost;
+}
+
 uint16_t ffd_neigh_get_cost(const ffd_neigh_t *neigh) {
 	if (!neigh) /* self */
 		return 0;
 
-	uint16_t txcost = neigh->txcost;
+	uint16_t txcost = ffd_neigh_get_txcost(neigh);
 	if (txcost < 256)
 		txcost = 256;
 

ffd/neigh.h

@@ -44,6 +44,7 @@ ffd_neigh_t* ffd_neigh_get(ffd_iface_t *iface, const eth_addr_t *addr);
 void ffd_neigh_free_list(ffd_neigh_t *neigh);
 
 uint16_t ffd_neigh_get_rxcost(const ffd_neigh_t *neigh);
+uint16_t ffd_neigh_get_txcost(const ffd_neigh_t *neigh);
 uint16_t ffd_neigh_get_cost(const ffd_neigh_t *neigh);
 void ffd_neigh_reset(ffd_iface_t *iface, ffd_neigh_t *neigh);
 

ffd/util.h

@@ -53,9 +53,9 @@ static inline bool are_eth_addrs_equal(const eth_addr_t *address1, const eth_add
 	return (a[0]==b[0] && a[1]==b[1] && a[2]==b[2] && a[3]==b[3] && a[4]==b[4] && a[5]==b[5]);
 }
 
-/* returns (tp1 - tp2) in milliseconds  */
+/* returns (tp1 - tp2) in centiseconds  */
 static inline int timespec_diff(const struct timespec *tp1, const struct timespec *tp2) {
-	return ((tp1->tv_sec - tp2->tv_sec))*1000 + (tp1->tv_nsec - tp2->tv_nsec)/1e6;
+	return ((tp1->tv_sec - tp2->tv_sec))*100 + (tp1->tv_nsec - tp2->tv_nsec)/1e7;
 }
 
 static inline int max(int a, int b) {