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LU-13569 lnet: Recover local NI w/exponential backoff interval
[fs/lustre-release.git] / lnet / lnet / lib-move.c
index 88ba642..c9b14f5 100644 (file)
@@ -27,7 +27,6 @@
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
- * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * lnet/lnet/lib-move.c
  *
@@ -840,8 +839,10 @@ lnet_post_send_locked(struct lnet_msg *msg, int do_send)
        LASSERT(!do_send || msg->msg_tx_delayed);
        LASSERT(!msg->msg_receiving);
        LASSERT(msg->msg_tx_committed);
+
        /* can't get here if we're sending to the loopback interface */
-       LASSERT(lp->lpni_nid != the_lnet.ln_loni->ni_nid);
+       if (the_lnet.ln_loni)
+               LASSERT(lp->lpni_nid != the_lnet.ln_loni->ni_nid);
 
        /* NB 'lp' is always the next hop */
        if ((msg->msg_target.pid & LNET_PID_USERFLAG) == 0 &&
@@ -1302,9 +1303,11 @@ lnet_select_peer_ni(struct lnet_ni *best_ni, lnet_nid_t dst_nid,
                INT_MIN;
        int best_lpni_healthv = (best_lpni) ?
                atomic_read(&best_lpni->lpni_healthv) : 0;
-       bool preferred = false;
-       bool ni_is_pref;
+       bool best_lpni_is_preferred = false;
+       bool lpni_is_preferred;
        int lpni_healthv;
+       __u32 lpni_sel_prio;
+       __u32 best_sel_prio = LNET_MAX_SELECTION_PRIORITY;
 
        while ((lpni = lnet_get_next_peer_ni_locked(peer, peer_net, lpni))) {
                /*
@@ -1312,56 +1315,76 @@ lnet_select_peer_ni(struct lnet_ni *best_ni, lnet_nid_t dst_nid,
                 * preferred, then let's use it
                 */
                if (best_ni) {
-                       ni_is_pref = lnet_peer_is_pref_nid_locked(lpni,
+                       lpni_is_preferred = lnet_peer_is_pref_nid_locked(lpni,
                                                                best_ni->ni_nid);
-                       CDEBUG(D_NET, "%s ni_is_pref = %d\n",
-                              libcfs_nid2str(best_ni->ni_nid), ni_is_pref);
+                       CDEBUG(D_NET, "%s lpni_is_preferred = %d\n",
+                              libcfs_nid2str(best_ni->ni_nid),
+                              lpni_is_preferred);
                } else {
-                       ni_is_pref = false;
+                       lpni_is_preferred = false;
                }
 
                lpni_healthv = atomic_read(&lpni->lpni_healthv);
+               lpni_sel_prio = lpni->lpni_sel_priority;
 
                if (best_lpni)
-                       CDEBUG(D_NET, "%s c:[%d, %d], s:[%d, %d]\n",
+                       CDEBUG(D_NET, "n:[%s, %s] h:[%d, %d] p:[%d, %d] c:[%d, %d] s:[%d, %d]\n",
                                libcfs_nid2str(lpni->lpni_nid),
+                               libcfs_nid2str(best_lpni->lpni_nid),
+                               lpni_healthv, best_lpni_healthv,
+                               lpni_sel_prio, best_sel_prio,
                                lpni->lpni_txcredits, best_lpni_credits,
                                lpni->lpni_seq, best_lpni->lpni_seq);
+               else
+                       goto select_lpni;
 
                /* pick the healthiest peer ni */
-               if (lpni_healthv < best_lpni_healthv) {
+               if (lpni_healthv < best_lpni_healthv)
+                       continue;
+               else if (lpni_healthv > best_lpni_healthv) {
+                       if (best_lpni_is_preferred)
+                               best_lpni_is_preferred = false;
+                       goto select_lpni;
+               }
+
+               if (lpni_sel_prio > best_sel_prio)
                        continue;
-               } else if (lpni_healthv > best_lpni_healthv) {
-                       best_lpni_healthv = lpni_healthv;
+               else if (lpni_sel_prio < best_sel_prio) {
+                       if (best_lpni_is_preferred)
+                               best_lpni_is_preferred = false;
+                       goto select_lpni;
+               }
+
                /* if this is a preferred peer use it */
-               } else if (!preferred && ni_is_pref) {
-                       preferred = true;
-               } else if (preferred && !ni_is_pref) {
-                       /*
-                        * this is not the preferred peer so let's ignore
+               if (!best_lpni_is_preferred && lpni_is_preferred) {
+                       best_lpni_is_preferred = true;
+                       goto select_lpni;
+               } else if (best_lpni_is_preferred && !lpni_is_preferred) {
+                       /* this is not the preferred peer so let's ignore
                         * it.
                         */
                        continue;
-               } else if (lpni->lpni_txcredits < best_lpni_credits) {
-                       /*
-                        * We already have a peer that has more credits
+               }
+
+               if (lpni->lpni_txcredits < best_lpni_credits)
+                       /* We already have a peer that has more credits
                         * available than this one. No need to consider
                         * this peer further.
                         */
                        continue;
-               } else if (lpni->lpni_txcredits == best_lpni_credits) {
-                       /*
-                        * The best peer found so far and the current peer
-                        * have the same number of available credits let's
-                        * make sure to select between them using Round
-                        * Robin
-                        */
-                       if (best_lpni) {
-                               if (best_lpni->lpni_seq <= lpni->lpni_seq)
-                                       continue;
-                       }
-               }
+               else if (lpni->lpni_txcredits > best_lpni_credits)
+                       goto select_lpni;
 
+               /* The best peer found so far and the current peer
+                * have the same number of available credits let's
+                * make sure to select between them using Round Robin
+                */
+               if (best_lpni && (best_lpni->lpni_seq <= lpni->lpni_seq))
+                       continue;
+select_lpni:
+               best_lpni_is_preferred = lpni_is_preferred;
+               best_lpni_healthv = lpni_healthv;
+               best_sel_prio = lpni_sel_prio;
                best_lpni = lpni;
                best_lpni_credits = lpni->lpni_txcredits;
        }
@@ -1585,6 +1608,7 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
        unsigned int shortest_distance;
        int best_credits;
        int best_healthv;
+       __u32 best_sel_prio;
 
        /*
         * If there is no peer_ni that we can send to on this network,
@@ -1594,6 +1618,7 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
                return best_ni;
 
        if (best_ni == NULL) {
+               best_sel_prio = LNET_MAX_SELECTION_PRIORITY;
                shortest_distance = UINT_MAX;
                best_credits = INT_MIN;
                best_healthv = 0;
@@ -1602,6 +1627,7 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
                                                     best_ni->ni_dev_cpt);
                best_credits = atomic_read(&best_ni->ni_tx_credits);
                best_healthv = atomic_read(&best_ni->ni_healthv);
+               best_sel_prio = best_ni->ni_sel_priority;
        }
 
        while ((ni = lnet_get_next_ni_locked(local_net, ni))) {
@@ -1609,10 +1635,12 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
                int ni_credits;
                int ni_healthv;
                int ni_fatal;
+               __u32 ni_sel_prio;
 
                ni_credits = atomic_read(&ni->ni_tx_credits);
                ni_healthv = atomic_read(&ni->ni_healthv);
                ni_fatal = atomic_read(&ni->ni_fatal_error_on);
+               ni_sel_prio = ni->ni_sel_priority;
 
                /*
                 * calculate the distance from the CPT on which
@@ -1623,12 +1651,6 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
                                            md_cpt,
                                            ni->ni_dev_cpt);
 
-               CDEBUG(D_NET, "compare ni %s [c:%d, d:%d, s:%d] with best_ni %s [c:%d, d:%d, s:%d]\n",
-                      libcfs_nid2str(ni->ni_nid), ni_credits, distance,
-                      ni->ni_seq, (best_ni) ? libcfs_nid2str(best_ni->ni_nid)
-                       : "not seleced", best_credits, shortest_distance,
-                       (best_ni) ? best_ni->ni_seq : 0);
-
                /*
                 * All distances smaller than the NUMA range
                 * are treated equally.
@@ -1640,31 +1662,47 @@ lnet_get_best_ni(struct lnet_net *local_net, struct lnet_ni *best_ni,
                 * Select on health, shorter distance, available
                 * credits, then round-robin.
                 */
-               if (ni_fatal) {
+               if (ni_fatal)
+                       continue;
+
+               if (best_ni)
+                       CDEBUG(D_NET, "compare ni %s [c:%d, d:%d, s:%d, p:%u] with best_ni %s [c:%d, d:%d, s:%d, p:%u]\n",
+                              libcfs_nid2str(ni->ni_nid), ni_credits, distance,
+                              ni->ni_seq, ni_sel_prio,
+                              (best_ni) ? libcfs_nid2str(best_ni->ni_nid)
+                              : "not selected", best_credits, shortest_distance,
+                              (best_ni) ? best_ni->ni_seq : 0,
+                              best_sel_prio);
+               else
+                       goto select_ni;
+
+               if (ni_healthv < best_healthv)
                        continue;
-               } else if (ni_healthv < best_healthv) {
+               else if (ni_healthv > best_healthv)
+                       goto select_ni;
+
+               if (ni_sel_prio > best_sel_prio)
                        continue;
-               } else if (ni_healthv > best_healthv) {
-                       best_healthv = ni_healthv;
-                       /*
-                        * If we're going to prefer this ni because it's
-                        * the healthiest, then we should set the
-                        * shortest_distance in the algorithm in case
-                        * there are multiple NIs with the same health but
-                        * different distances.
-                        */
-                       if (distance < shortest_distance)
-                               shortest_distance = distance;
-               } else if (distance > shortest_distance) {
+               else if (ni_sel_prio < best_sel_prio)
+                       goto select_ni;
+
+               if (distance > shortest_distance)
                        continue;
-               } else if (distance < shortest_distance) {
-                       shortest_distance = distance;
-               } else if (ni_credits < best_credits) {
+               else if (distance < shortest_distance)
+                       goto select_ni;
+
+               if (ni_credits < best_credits)
                        continue;
-               } else if (ni_credits == best_credits) {
-                       if (best_ni && best_ni->ni_seq <= ni->ni_seq)
-                               continue;
-               }
+               else if (ni_credits > best_credits)
+                       goto select_ni;
+
+               if (best_ni && best_ni->ni_seq <= ni->ni_seq)
+                       continue;
+
+select_ni:
+               best_sel_prio = ni_sel_prio;
+               shortest_distance = distance;
+               best_healthv = ni_healthv;
                best_ni = ni;
                best_credits = ni_credits;
        }
@@ -1724,6 +1762,9 @@ lnet_handle_lo_send(struct lnet_send_data *sd)
        struct lnet_msg *msg = sd->sd_msg;
        int cpt = sd->sd_cpt;
 
+       if (the_lnet.ln_state != LNET_STATE_RUNNING)
+               return -ESHUTDOWN;
+
        /* No send credit hassles with LOLND */
        lnet_ni_addref_locked(the_lnet.ln_loni, cpt);
        msg->msg_hdr.dest_nid = cpu_to_le64(the_lnet.ln_loni->ni_nid);
@@ -1750,11 +1791,24 @@ lnet_handle_send(struct lnet_send_data *sd)
        __u32 routing = send_case & REMOTE_DST;
         struct lnet_rsp_tracker *rspt;
 
-       /*
-        * Increment sequence number of the selected peer so that we
-        * pick the next one in Round Robin.
+       /* Increment sequence number of the selected peer, peer net,
+        * local ni and local net so that we pick the next ones
+        * in Round Robin.
         */
        best_lpni->lpni_seq++;
+       best_lpni->lpni_peer_net->lpn_seq++;
+       best_ni->ni_seq++;
+       best_ni->ni_net->net_seq++;
+
+       CDEBUG(D_NET, "%s NI seq info: [%d:%d:%d:%u] %s LPNI seq info [%d:%d:%d:%u]\n",
+              libcfs_nid2str(best_ni->ni_nid),
+              best_ni->ni_seq, best_ni->ni_net->net_seq,
+              atomic_read(&best_ni->ni_tx_credits),
+              best_ni->ni_sel_priority,
+              libcfs_nid2str(best_lpni->lpni_nid),
+              best_lpni->lpni_seq, best_lpni->lpni_peer_net->lpn_seq,
+              best_lpni->lpni_txcredits,
+              best_lpni->lpni_sel_priority);
 
        /*
         * grab a reference on the peer_ni so it sticks around even if
@@ -1948,8 +2002,7 @@ struct lnet_ni *
 lnet_find_best_ni_on_spec_net(struct lnet_ni *cur_best_ni,
                              struct lnet_peer *peer,
                              struct lnet_peer_net *peer_net,
-                             int cpt,
-                             bool incr_seq)
+                             int cpt)
 {
        struct lnet_net *local_net;
        struct lnet_ni *best_ni;
@@ -1969,9 +2022,6 @@ lnet_find_best_ni_on_spec_net(struct lnet_ni *cur_best_ni,
        best_ni = lnet_get_best_ni(local_net, cur_best_ni,
                                   peer, peer_net, cpt);
 
-       if (incr_seq && best_ni)
-               best_ni->ni_seq++;
-
        return best_ni;
 }
 
@@ -1980,6 +2030,7 @@ lnet_initiate_peer_discovery(struct lnet_peer_ni *lpni, struct lnet_msg *msg,
                             int cpt)
 {
        struct lnet_peer *peer;
+       struct lnet_peer_ni *new_lpni;
        int rc;
 
        lnet_peer_ni_addref_locked(lpni);
@@ -2001,21 +2052,38 @@ lnet_initiate_peer_discovery(struct lnet_peer_ni *lpni, struct lnet_msg *msg,
                lnet_peer_ni_decref_locked(lpni);
                return rc;
        }
-       /* The peer may have changed. */
-       peer = lpni->lpni_peer_net->lpn_peer;
+
+       new_lpni = lnet_find_peer_ni_locked(lpni->lpni_nid);
+       if (!new_lpni) {
+               lnet_peer_ni_decref_locked(lpni);
+               return -ENOENT;
+       }
+
+       peer = new_lpni->lpni_peer_net->lpn_peer;
        spin_lock(&peer->lp_lock);
-       if (lnet_peer_is_uptodate_locked(peer)) {
+       if (lpni == new_lpni && lnet_peer_is_uptodate_locked(peer)) {
+               /* The peer NI did not change and the peer is up to date.
+                * Nothing more to do.
+                */
                spin_unlock(&peer->lp_lock);
                lnet_peer_ni_decref_locked(lpni);
+               lnet_peer_ni_decref_locked(new_lpni);
                return 0;
        }
-       /* queue message and return */
+       spin_unlock(&peer->lp_lock);
+
+       /* Either the peer NI changed during discovery, or the peer isn't up
+        * to date. In both cases we want to queue the message on the
+        * (possibly new) peer's pending queue and queue the peer for discovery
+        */
        msg->msg_sending = 0;
        msg->msg_txpeer = NULL;
-       list_add_tail(&msg->msg_list, &peer->lp_dc_pendq);
-       spin_unlock(&peer->lp_lock);
+       lnet_net_unlock(cpt);
+       lnet_peer_queue_message(peer, msg);
+       lnet_net_lock(cpt);
 
        lnet_peer_ni_decref_locked(lpni);
+       lnet_peer_ni_decref_locked(new_lpni);
 
        CDEBUG(D_NET, "msg %p delayed. %s pending discovery\n",
               msg, libcfs_nid2str(peer->lp_primary_nid));
@@ -2195,8 +2263,7 @@ use_lpn:
                sd->sd_best_ni = lnet_find_best_ni_on_spec_net(NULL, gw,
                                        lnet_peer_get_net_locked(gw,
                                                                 local_lnet),
-                                       sd->sd_md_cpt,
-                                       true);
+                                       sd->sd_md_cpt);
 
        if (!sd->sd_best_ni) {
                CERROR("Internal Error. Expected local ni on %s but non found :%s\n",
@@ -2281,9 +2348,19 @@ struct lnet_ni *
 lnet_find_best_ni_on_local_net(struct lnet_peer *peer, int md_cpt,
                               bool discovery)
 {
-       struct lnet_peer_net *peer_net = NULL;
+       struct lnet_peer_net *lpn = NULL;
+       struct lnet_peer_net *best_lpn = NULL;
+       struct lnet_net *net = NULL;
+       struct lnet_net *best_net = NULL;
        struct lnet_ni *best_ni = NULL;
-       int lpn_healthv = 0;
+       int best_lpn_healthv = 0;
+       int best_net_healthv = 0;
+       int net_healthv;
+       __u32 best_lpn_sel_prio = LNET_MAX_SELECTION_PRIORITY;
+       __u32 lpn_sel_prio;
+       __u32 best_net_sel_prio = LNET_MAX_SELECTION_PRIORITY;
+       __u32 net_sel_prio;
+       bool exit = false;
 
        /*
         * The peer can have multiple interfaces, some of them can be on
@@ -2293,35 +2370,82 @@ lnet_find_best_ni_on_local_net(struct lnet_peer *peer, int md_cpt,
         */
 
        /* go through all the peer nets and find the best_ni */
-       list_for_each_entry(peer_net, &peer->lp_peer_nets, lpn_peer_nets) {
+       list_for_each_entry(lpn, &peer->lp_peer_nets, lpn_peer_nets) {
                /*
                 * The peer's list of nets can contain non-local nets. We
                 * want to only examine the local ones.
                 */
-               if (!lnet_get_net_locked(peer_net->lpn_net_id))
-                       continue;
-
-               /* always select the lpn with the best health */
-               if (lpn_healthv <= peer_net->lpn_healthv)
-                       lpn_healthv = peer_net->lpn_healthv;
-               else
+               net = lnet_get_net_locked(lpn->lpn_net_id);
+               if (!net)
                        continue;
 
-               best_ni = lnet_find_best_ni_on_spec_net(best_ni, peer, peer_net,
-                                                       md_cpt, false);
+               lpn_sel_prio = lpn->lpn_sel_priority;
+               net_healthv = lnet_get_net_healthv_locked(net);
+               net_sel_prio = net->net_sel_priority;
 
                /*
                 * if this is a discovery message and lp_disc_net_id is
                 * specified then use that net to send the discovery on.
                 */
-               if (peer->lp_disc_net_id == peer_net->lpn_net_id &&
-                   discovery)
+               if (peer->lp_disc_net_id == lpn->lpn_net_id &&
+                   discovery) {
+                       exit = true;
+                       goto select_lpn;
+               }
+
+               if (!best_lpn)
+                       goto select_lpn;
+
+               /* always select the lpn with the best health */
+               if (best_lpn_healthv > lpn->lpn_healthv)
+                       continue;
+               else if (best_lpn_healthv < lpn->lpn_healthv)
+                       goto select_lpn;
+
+               /* select the preferred peer and local nets */
+               if (best_lpn_sel_prio < lpn_sel_prio)
+                       continue;
+               else if (best_lpn_sel_prio > lpn_sel_prio)
+                       goto select_lpn;
+
+               if (best_net_healthv > net_healthv)
+                       continue;
+               else if (best_net_healthv < net_healthv)
+                       goto select_lpn;
+
+               if (best_net_sel_prio < net_sel_prio)
+                       continue;
+               else if (best_net_sel_prio > net_sel_prio)
+                       goto select_lpn;
+
+               if (best_lpn->lpn_seq < lpn->lpn_seq)
+                       continue;
+               else if (best_lpn->lpn_seq > lpn->lpn_seq)
+                       goto select_lpn;
+
+               /* round robin over the local networks */
+               if (best_net->net_seq <= net->net_seq)
+                       continue;
+
+select_lpn:
+               best_net_healthv = net_healthv;
+               best_net_sel_prio = net_sel_prio;
+               best_lpn_healthv = lpn->lpn_healthv;
+               best_lpn_sel_prio = lpn_sel_prio;
+               best_lpn = lpn;
+               best_net = net;
+
+               if (exit)
                        break;
        }
 
-       if (best_ni)
-               /* increment sequence number so we can round robin */
-               best_ni->ni_seq++;
+       if (best_lpn) {
+               /* Select the best NI on the same net as best_lpn chosen
+                * above
+                */
+               best_ni = lnet_find_best_ni_on_spec_net(NULL, peer,
+                                                       best_lpn, md_cpt);
+       }
 
        return best_ni;
 }
@@ -2382,7 +2506,7 @@ lnet_select_preferred_best_ni(struct lnet_send_data *sd)
                best_ni =
                  lnet_find_best_ni_on_spec_net(NULL, sd->sd_peer,
                                                sd->sd_best_lpni->lpni_peer_net,
-                                               sd->sd_md_cpt, true);
+                                               sd->sd_md_cpt);
                /* If there is no best_ni we don't have a route */
                if (!best_ni) {
                        CERROR("no path to %s from net %s\n",
@@ -2438,8 +2562,7 @@ lnet_handle_any_local_nmr_dst(struct lnet_send_data *sd)
                sd->sd_best_ni = lnet_find_best_ni_on_spec_net(NULL,
                                                               sd->sd_peer,
                                                               sd->sd_best_lpni->lpni_peer_net,
-                                                              sd->sd_md_cpt,
-                                                              true);
+                                                              sd->sd_md_cpt);
                if (!sd->sd_best_ni) {
                        CERROR("Unable to forward message to %s. No local NI available\n",
                               libcfs_nid2str(sd->sd_dst_nid));
@@ -2472,7 +2595,7 @@ lnet_handle_any_mr_dsta(struct lnet_send_data *sd)
                sd->sd_best_ni =
                  lnet_find_best_ni_on_spec_net(NULL, sd->sd_peer,
                                                sd->sd_best_lpni->lpni_peer_net,
-                                               sd->sd_md_cpt, true);
+                                               sd->sd_md_cpt);
 
                if (!sd->sd_best_ni) {
                        /*
@@ -3225,6 +3348,7 @@ lnet_recover_local_nis(void)
        lnet_nid_t nid;
        int healthv;
        int rc;
+       time64_t now;
 
        /*
         * splice the recovery queue on a local queue. We will iterate
@@ -3238,6 +3362,8 @@ lnet_recover_local_nis(void)
                         &local_queue);
        lnet_net_unlock(0);
 
+       now = ktime_get_seconds();
+
        list_for_each_entry_safe(ni, tmp, &local_queue, ni_recovery) {
                /*
                 * if an NI is being deleted or it is now healthy, there
@@ -3271,9 +3397,15 @@ lnet_recover_local_nis(void)
                        ni->ni_recovery_state &= ~LNET_NI_RECOVERY_FAILED;
                }
 
+
                lnet_ni_unlock(ni);
-               lnet_net_unlock(0);
 
+               if (now < ni->ni_next_ping) {
+                       lnet_net_unlock(0);
+                       continue;
+               }
+
+               lnet_net_unlock(0);
 
                CDEBUG(D_NET, "attempting to recover local ni: %s\n",
                       libcfs_nid2str(ni->ni_nid));
@@ -3341,30 +3473,20 @@ lnet_recover_local_nis(void)
                                LNetMDUnlink(mdh);
                                continue;
                        }
-                       /*
-                        * Same note as in lnet_recover_peer_nis(). When
-                        * we're sending the ping, the NI is free to be
-                        * deleted or manipulated. By this point it
-                        * could've been added back on the recovery queue,
-                        * and a refcount taken on it.
-                        * So we can't just add it blindly again or we'll
-                        * corrupt the queue. We must check under lock if
-                        * it's not on any list and if not then add it
-                        * to the processed list, which will eventually be
-                        * spliced back on to the recovery queue.
-                        */
+                       ni->ni_ping_count++;
+
                        ni->ni_ping_mdh = mdh;
-                       if (list_empty(&ni->ni_recovery)) {
-                               list_add_tail(&ni->ni_recovery, &processed_list);
-                               lnet_ni_addref_locked(ni, 0);
-                       }
-                       lnet_net_unlock(0);
+                       lnet_ni_add_to_recoveryq_locked(ni, &processed_list,
+                                                       now);
 
-                       lnet_ni_lock(ni);
-                       if (rc)
+                       if (rc) {
+                               lnet_ni_lock(ni);
                                ni->ni_recovery_state &= ~LNET_NI_RECOVERY_PENDING;
-               }
-               lnet_ni_unlock(ni);
+                               lnet_ni_unlock(ni);
+                       }
+                       lnet_net_unlock(0);
+               } else
+                       lnet_ni_unlock(ni);
        }
 
        /*
@@ -3486,6 +3608,7 @@ lnet_recover_peer_nis(void)
        lnet_nid_t nid;
        int healthv;
        int rc;
+       time64_t now;
 
        /*
         * Always use cpt 0 for locking across all interactions with
@@ -3496,6 +3619,8 @@ lnet_recover_peer_nis(void)
                         &local_queue);
        lnet_net_unlock(0);
 
+       now = ktime_get_seconds();
+
        list_for_each_entry_safe(lpni, tmp, &local_queue,
                                 lpni_recovery) {
                /*
@@ -3526,6 +3651,12 @@ lnet_recover_peer_nis(void)
                }
 
                spin_unlock(&lpni->lpni_lock);
+
+               if (now < lpni->lpni_next_ping) {
+                       lnet_net_unlock(0);
+                       continue;
+               }
+
                lnet_net_unlock(0);
 
                /*
@@ -3575,30 +3706,24 @@ lnet_recover_peer_nis(void)
                                continue;
                        }
 
+                       lpni->lpni_ping_count++;
+
                        lpni->lpni_recovery_ping_mdh = mdh;
-                       /*
-                        * While we're unlocked the lpni could've been
-                        * readded on the recovery queue. In this case we
-                        * don't need to add it to the local queue, since
-                        * it's already on there and the thread that added
-                        * it would've incremented the refcount on the
-                        * peer, which means we need to decref the refcount
-                        * that was implicitly grabbed by find_peer_ni_locked.
-                        * Otherwise, if the lpni is still not on
-                        * the recovery queue, then we'll add it to the
-                        * processed list.
-                        */
-                       if (list_empty(&lpni->lpni_recovery))
-                               list_add_tail(&lpni->lpni_recovery, &processed_list);
-                       else
-                               lnet_peer_ni_decref_locked(lpni);
-                       lnet_net_unlock(0);
 
-                       spin_lock(&lpni->lpni_lock);
-                       if (rc)
+                       lnet_peer_ni_add_to_recoveryq_locked(lpni,
+                                                            &processed_list,
+                                                            now);
+                       if (rc) {
+                               spin_lock(&lpni->lpni_lock);
                                lpni->lpni_state &= ~LNET_PEER_NI_RECOVERY_PENDING;
-               }
-               spin_unlock(&lpni->lpni_lock);
+                               spin_unlock(&lpni->lpni_lock);
+                       }
+
+                       /* Drop the ref taken by lnet_find_peer_ni_locked() */
+                       lnet_peer_ni_decref_locked(lpni);
+                       lnet_net_unlock(0);
+               } else
+                       spin_unlock(&lpni->lpni_lock);
        }
 
        list_splice_init(&processed_list, &local_queue);
@@ -4449,61 +4574,6 @@ lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid,
                goto drop;
        }
 
-       if (lnet_drop_asym_route && for_me &&
-           LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) {
-               struct lnet_net *net;
-               struct lnet_remotenet *rnet;
-               bool found = true;
-
-               /* we are dealing with a routed message,
-                * so see if route to reach src_nid goes through from_nid
-                */
-               lnet_net_lock(cpt);
-               net = lnet_get_net_locked(LNET_NIDNET(ni->ni_nid));
-               if (!net) {
-                       lnet_net_unlock(cpt);
-                       CERROR("net %s not found\n",
-                              libcfs_net2str(LNET_NIDNET(ni->ni_nid)));
-                       return -EPROTO;
-               }
-
-               rnet = lnet_find_rnet_locked(LNET_NIDNET(src_nid));
-               if (rnet) {
-                       struct lnet_peer *gw = NULL;
-                       struct lnet_peer_ni *lpni = NULL;
-                       struct lnet_route *route;
-
-                       list_for_each_entry(route, &rnet->lrn_routes, lr_list) {
-                               found = false;
-                               gw = route->lr_gateway;
-                               if (route->lr_lnet != net->net_id)
-                                       continue;
-                               /*
-                                * if the nid is one of the gateway's NIDs
-                                * then this is a valid gateway
-                                */
-                               while ((lpni = lnet_get_next_peer_ni_locked(gw,
-                                               NULL, lpni)) != NULL) {
-                                       if (lpni->lpni_nid == from_nid) {
-                                               found = true;
-                                               break;
-                                       }
-                               }
-                       }
-               }
-               lnet_net_unlock(cpt);
-               if (!found) {
-                       /* we would not use from_nid to route a message to
-                        * src_nid
-                        * => asymmetric routing detected but forbidden
-                        */
-                       CERROR("%s, src %s: Dropping asymmetrical route %s\n",
-                              libcfs_nid2str(from_nid),
-                              libcfs_nid2str(src_nid), lnet_msgtyp2str(type));
-                       goto drop;
-               }
-       }
-
        msg = lnet_msg_alloc();
        if (msg == NULL) {
                CERROR("%s, src %s: Dropping %s (out of memory)\n",
@@ -4554,8 +4624,65 @@ lnet_parse(struct lnet_ni *ni, struct lnet_hdr *hdr, lnet_nid_t from_nid,
                goto drop;
        }
 
-       if (the_lnet.ln_routing)
-               lpni->lpni_last_alive = ktime_get_seconds();
+       /* If this message was forwarded to us from a router then we may need
+        * to update router aliveness or check for an asymmetrical route
+        * (or both)
+        */
+       if (((lnet_drop_asym_route && for_me) ||
+            !lpni->lpni_peer_net->lpn_peer->lp_alive) &&
+           LNET_NIDNET(src_nid) != LNET_NIDNET(from_nid)) {
+               __u32 src_net_id = LNET_NIDNET(src_nid);
+               struct lnet_peer *gw = lpni->lpni_peer_net->lpn_peer;
+               struct lnet_route *route;
+               bool found = false;
+
+               list_for_each_entry(route, &gw->lp_routes, lr_gwlist) {
+                       if (route->lr_net == src_net_id) {
+                               found = true;
+                               /* If we're transitioning the gateway from
+                                * dead -> alive, and discovery is disabled
+                                * locally or on the gateway, then we need to
+                                * update the cached route aliveness for each
+                                * route to the src_nid's net.
+                                *
+                                * Otherwise, we're only checking for
+                                * symmetrical route, and we can break the
+                                * loop
+                                */
+                               if (!gw->lp_alive &&
+                                   lnet_is_discovery_disabled(gw))
+                                       lnet_set_route_aliveness(route, true);
+                               else
+                                       break;
+                       }
+               }
+               if (lnet_drop_asym_route && for_me && !found) {
+                       lnet_net_unlock(cpt);
+                       /* we would not use from_nid to route a message to
+                        * src_nid
+                        * => asymmetric routing detected but forbidden
+                        */
+                       CERROR("%s, src %s: Dropping asymmetrical route %s\n",
+                              libcfs_nid2str(from_nid),
+                              libcfs_nid2str(src_nid), lnet_msgtyp2str(type));
+                       lnet_msg_free(msg);
+                       goto drop;
+               }
+               if (!gw->lp_alive) {
+                       struct lnet_peer_net *lpn;
+                       struct lnet_peer_ni *lpni2;
+
+                       gw->lp_alive = true;
+                       /* Mark all remote NIs on src_nid's net UP */
+                       lpn = lnet_peer_get_net_locked(gw, src_net_id);
+                       if (lpn)
+                               list_for_each_entry(lpni2, &lpn->lpn_peer_nis,
+                                                   lpni_peer_nis)
+                                       lpni2->lpni_ns_status = LNET_NI_STATUS_UP;
+               }
+       }
+
+       lpni->lpni_last_alive = ktime_get_seconds();
 
        msg->msg_rxpeer = lpni;
        msg->msg_rxni = ni;