LU-11475 lnet: transfer routers

[fs/lustre-release.git] / lnet / lnet / router.c

diff --git a/lnet/lnet/router.c b/lnet/lnet/router.c
index 9ac6de1..0346cf0 100644 (file)
--- a/lnet/lnet/router.c
+++ b/lnet/lnet/router.c
@@ -141,6 +141,35 @@ rtr_sensitivity_set(const char *val, cfs_kernel_param_arg_t *kp)
        return 0;
 }
 
+void
+lnet_rtr_transfer_to_peer(struct lnet_peer *src, struct lnet_peer *target)
+{
+       struct lnet_route *route;
+
+       lnet_net_lock(LNET_LOCK_EX);
+       target->lp_rtr_refcount += src->lp_rtr_refcount;
+       /* move the list of queued messages to the new peer */
+       list_splice_init(&src->lp_rtrq, &target->lp_rtrq);
+       /* move all the routes that reference the peer */
+       list_splice_init(&src->lp_routes, &target->lp_routes);
+       /* update all the routes to point to the new peer */
+       list_for_each_entry(route, &target->lp_routes, lr_gwlist)
+               route->lr_gateway = target;
+       /* remove the old peer from the ln_routers list */
+       list_del_init(&src->lp_rtr_list);
+       /* add the new peer to the ln_routers list */
+       if (list_empty(&target->lp_rtr_list)) {
+               lnet_peer_addref_locked(target);
+               list_add_tail(&target->lp_rtr_list, &the_lnet.ln_routers);
+       }
+       /* reset the ref count on the old peer and decrement its ref count */
+       src->lp_rtr_refcount = 0;
+       lnet_peer_decref_locked(src);
+       /* update the router version */
+       the_lnet.ln_routers_version++;
+       lnet_net_unlock(LNET_LOCK_EX);
+}
+
 int
 lnet_peers_start_down(void)
 {