LU-10391 lnet: find correct primary for peer

If the peer has a large-address for the primary, it can now be found.

Test-Parameters: trivial testlist=sanity-lnet
Test-Parameters: serverversion=2.12 serverdistro=el7.9 testlist=runtests
Test-Parameters: clientversion=2.12 testlist=runtests
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: Ie14ae970254bb58e26970bb09e7645979daa418a
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/44632
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Reviewed-by: Frank Sehr <fsehr@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>

diff --git a/lnet/lnet/peer.c b/lnet/lnet/peer.c
index 7be3eb4..d9d8798 100644 (file)
--- a/lnet/lnet/peer.c
+++ b/lnet/lnet/peer.c
@@ -2600,11 +2600,40 @@ lnet_discovery_event_ack(struct lnet_peer *lp, struct lnet_event *ev)
               libcfs_nidstr(&lp->lp_primary_nid), ev->status);
 }
 
+static bool find_primary(struct lnet_nid *nid,
+                        struct lnet_ping_buffer *pbuf)
+{
+       struct lnet_ping_info *pi = &pbuf->pb_info;
+       struct lnet_ping_iter piter;
+       __u32 *stp;
+
+       if (pi->pi_features & LNET_PING_FEAT_PRIMARY_LARGE) {
+               /* First large nid is primary */
+               for (stp = ping_iter_first(&piter, pbuf, nid);
+                    stp;
+                    stp = ping_iter_next(&piter, nid)) {
+                       if (nid_is_nid4(nid))
+                               continue;
+                       /* nid has already been copied in */
+                       return true;
+               }
+               /* no large nids ... weird ... ignore the flag
+                * and use first nid.
+                */
+       }
+       /* pi_nids[1] is primary */
+       if (pi->pi_nnis < 2)
+               return false;
+       lnet_nid4_to_nid(pbuf->pb_info.pi_ni[1].ns_nid, nid);
+       return true;
+}
+
 /* Handle a Reply message. This is the reply to a Ping message. */
 static void
 lnet_discovery_event_reply(struct lnet_peer *lp, struct lnet_event *ev)
 {
        struct lnet_ping_buffer *pbuf;
+       struct lnet_nid primary;
        int infobytes;
        int rc;
        bool ping_feat_disc;
@@ -2747,9 +2776,8 @@ lnet_discovery_event_reply(struct lnet_peer *lp, struct lnet_event *ev)
         * available if the reply came from a Multi-Rail peer.
         */
        if (pbuf->pb_info.pi_features & LNET_PING_FEAT_MULTI_RAIL &&
-           pbuf->pb_info.pi_nnis > 1 &&
-           lnet_nid_to_nid4(&lp->lp_primary_nid) ==
-           pbuf->pb_info.pi_ni[1].ns_nid) {
+           find_primary(&primary, pbuf) &&
+           nid_same(&lp->lp_primary_nid, &primary)) {
                if (LNET_PING_BUFFER_SEQNO(pbuf) < lp->lp_peer_seqno)
                        CDEBUG(D_NET, "peer %s: seq# got %u have %u. peer rebooted?\n",
                                libcfs_nidstr(&lp->lp_primary_nid),
@@ -3098,11 +3126,11 @@ static int lnet_peer_merge_data(struct lnet_peer *lp,
         * peer's lp_peer_nets list, and the peer NI for the primary NID should
         * be the first entry in its peer net's lpn_peer_nis list.
         */
-       lnet_nid4_to_nid(pbuf->pb_info.pi_ni[1].ns_nid, &nid);
+       find_primary(&nid, pbuf);
        lpni = lnet_peer_ni_find_locked(&nid);
        if (!lpni) {
                CERROR("Internal error: Failed to lookup peer NI for primary NID: %s\n",
-                      libcfs_nid2str(pbuf->pb_info.pi_ni[1].ns_nid));
+                      libcfs_nidstr(&nid));
                goto out;
        }
 
@@ -3358,11 +3386,10 @@ __must_hold(&lp->lp_lock)
         * primary NID to the correct value here. Moreover, this peer
         * can show up with only the loopback NID in the ping buffer.
         */
-       if (pbuf->pb_info.pi_nnis <= 1) {
+       if (!find_primary(&nid, pbuf)) {
                lnet_ping_buffer_decref(pbuf);
                goto out;
        }
-       lnet_nid4_to_nid(pbuf->pb_info.pi_ni[1].ns_nid, &nid);
        if (nid_is_lo0(&lp->lp_primary_nid)) {
                rc = lnet_peer_set_primary_nid(lp, &nid, flags);
                if (rc)