staging: lustre: reflect down routes in /proc/sys/lnet/routes

We consider routes "down" if the router is down or the router
NI for the target network is down. This should be reflected
in the output of /proc/sys/lnet/routes
Signed-off-by: Chris Horn <hornc@cray.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3679
Reviewed-on: http://review.whamcloud.com/7857Reviewed-by: Cory Spitz <spitzcor@cray.com>
Reviewed-by: Isaac Huang <he.huang@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/include/linux/lnet/lib-lnet.h

@@ -64,6 +64,19 @@ extern lnet_t	the_lnet;	/* THE network */
 /** exclusive lock */
 #define LNET_LOCK_EX		CFS_PERCPT_LOCK_EX
 
+static inline int lnet_is_route_alive(lnet_route_t *route)
+{
+	/* gateway is down */
+	if (!route->lr_gateway->lp_alive)
+		return 0;
+	/* no NI status, assume it's alive */
+	if ((route->lr_gateway->lp_ping_feats &
+	     LNET_PING_FEAT_NI_STATUS) == 0)
+		return 1;
+	/* has NI status, check # down NIs */
+	return route->lr_downis == 0;
+}
+
 static inline int lnet_is_wire_handle_none(lnet_handle_wire_t *wh)
 {
 	return (wh->wh_interface_cookie == LNET_WIRE_HANDLE_COOKIE_NONE &&

drivers/staging/lustre/lnet/lnet/lib-move.c

@@ -1156,9 +1156,7 @@ lnet_find_route_locked(lnet_ni_t *ni, lnet_nid_t target, lnet_nid_t rtr_nid)
 	list_for_each_entry(route, &rnet->lrn_routes, lr_list) {
 		lp = route->lr_gateway;
 
-		if (!lp->lp_alive || /* gateway is down */
-		    ((lp->lp_ping_feats & LNET_PING_FEAT_NI_STATUS) &&
-		     route->lr_downis)) /* NI to target is down */
+		if (!lnet_is_route_alive(route))
 			continue;
 
 		if (ni && lp->lp_ni != ni)

drivers/staging/lustre/lnet/lnet/router_proc.c

@@ -242,7 +242,7 @@ static int proc_lnet_routes(struct ctl_table *table, int write,
 			unsigned int hops = route->lr_hops;
 			unsigned int priority = route->lr_priority;
 			lnet_nid_t nid = route->lr_gateway->lp_nid;
-			int alive = route->lr_gateway->lp_alive;
+			int alive = lnet_is_route_alive(route);
 
 			s += snprintf(s, tmpstr + tmpsiz - s,
 				      "%-8s %4u %8u %7s %s\n",