LU-14668 lnet: Peers added via kernel API should be permanent

The LNetAddPeer() API allows Lustre to predefine the Peer for LNet.
Originally these peers would be temporary and potentially re-created
via discovery. Instead, let's make these peers permanent. This allows
Lustre to dictate the primary NID of the peer. LNet makes sure this
primary NID is not changed afterwards.

Test-Parameters: trivial
Signed-off-by: Amir Shehata <ashehata@whamcloud.com>
Signed-off-by: Chris Horn <chris.horn@hpe.com>
Change-Id: I3f54c04719c9e0374176682af08183f0c93ef737
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/43788
Tested-by: Maloo <maloo@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Reviewed-by: Cyril Bordage <cbordage@whamcloud.com>
Reviewed-by: Frank Sehr <fsehr@whamcloud.com>

diff --git a/lnet/include/lnet/lib-lnet.h b/lnet/include/lnet/lib-lnet.h
index 7dd5148..de3aa44 100644 (file)
--- a/lnet/include/lnet/lib-lnet.h
+++ b/lnet/include/lnet/lib-lnet.h
@@ -1029,8 +1029,7 @@ void lnet_peer_clr_pref_rtrs(struct lnet_peer_ni *lpni);
 int lnet_peer_add_pref_rtr(struct lnet_peer_ni *lpni, struct lnet_nid *nid);
 int lnet_peer_ni_set_non_mr_pref_nid(struct lnet_peer_ni *lpni,
                                     struct lnet_nid *nid);
-int lnet_add_peer_ni(struct lnet_nid *key_nid, struct lnet_nid *nid, bool mr,
-                    bool temp);
+int lnet_user_add_peer_ni(struct lnet_nid *key_nid, struct lnet_nid *nid, bool mr);
 int lnet_del_peer_ni(struct lnet_nid *key_nid, struct lnet_nid *nid);
 int lnet_get_peer_info(struct lnet_ioctl_peer_cfg *cfg, void __user *bulk);
 int lnet_get_peer_ni_info(__u32 peer_index, __u64 *nid,

diff --git a/lnet/lnet/api-ni.c b/lnet/lnet/api-ni.c
index 58ebd4d..cb068b0 100644 (file)
--- a/lnet/lnet/api-ni.c
+++ b/lnet/lnet/api-ni.c
@@ -4317,7 +4317,7 @@ LNetCtl(unsigned int cmd, void *arg)
                mutex_lock(&the_lnet.ln_api_mutex);
                lnet_nid4_to_nid(cfg->prcfg_prim_nid, &prim_nid);
                lnet_nid4_to_nid(cfg->prcfg_cfg_nid, &nid);
-               rc = lnet_add_peer_ni(&prim_nid, &nid, cfg->prcfg_mr, false);
+               rc = lnet_user_add_peer_ni(&prim_nid, &nid, cfg->prcfg_mr);
                mutex_unlock(&the_lnet.ln_api_mutex);
                return rc;
        }

diff --git a/lnet/lnet/peer.c b/lnet/lnet/peer.c
index e2ae275..6e71ec5 100644 (file)
--- a/lnet/lnet/peer.c
+++ b/lnet/lnet/peer.c
@@ -47,6 +47,8 @@
 #define LNET_REDISCOVER_PEER   (1)
 
 static int lnet_peer_queue_for_discovery(struct lnet_peer *lp);
+static int lnet_add_peer_ni(struct lnet_nid *prim_nid, struct lnet_nid *nid, bool mr,
+                           unsigned int flags);
 
 static void
 lnet_peer_remove_from_remote_list(struct lnet_peer_ni *lpni)
@@ -1375,7 +1377,8 @@ LNetAddPeer(lnet_nid_t *nids, __u32 num_nids)
                lnet_nid4_to_nid(nids[i], &nid);
                if (LNET_NID_IS_ANY(&pnid)) {
                        lnet_nid4_to_nid(nids[i], &pnid);
-                       rc = lnet_add_peer_ni(&pnid, &LNET_ANY_NID, mr, true);
+                       rc = lnet_add_peer_ni(&pnid, &LNET_ANY_NID, mr,
+                                             LNET_PEER_LOCK_PRIMARY);
                        if (rc == -EALREADY) {
                                struct lnet_peer *lp;
 
@@ -1391,10 +1394,12 @@ LNetAddPeer(lnet_nid_t *nids, __u32 num_nids)
                        }
                } else if (lnet_peer_discovery_disabled) {
                        lnet_nid4_to_nid(nids[i], &nid);
-                       rc = lnet_add_peer_ni(&nid, &LNET_ANY_NID, mr, true);
+                       rc = lnet_add_peer_ni(&nid, &LNET_ANY_NID, mr,
+                                             LNET_PEER_LOCK_PRIMARY);
                } else {
                        lnet_nid4_to_nid(nids[i], &nid);
-                       rc = lnet_add_peer_ni(&pnid, &nid, mr, true);
+                       rc = lnet_add_peer_ni(&pnid, &nid, mr,
+                                             LNET_PEER_LOCK_PRIMARY);
                }
 
                if (rc && rc != -EEXIST)
@@ -1929,22 +1934,18 @@ out:
  * The caller must hold ln_api_mutex. This prevents the peer from
  * being created/modified/deleted by a different thread.
  */
-int
+static int
 lnet_add_peer_ni(struct lnet_nid *prim_nid, struct lnet_nid *nid, bool mr,
-                bool temp)
+                unsigned int flags)
 __must_hold(&the_lnet.ln_api_mutex)
 {
        struct lnet_peer *lp = NULL;
        struct lnet_peer_ni *lpni;
-       unsigned int flags = 0;
 
        /* The prim_nid must always be specified */
        if (LNET_NID_IS_ANY(prim_nid))
                return -EINVAL;
 
-       if (!temp)
-               flags = LNET_PEER_CONFIGURED;
-
        if (mr)
                flags |= LNET_PEER_MULTI_RAIL;
 
@@ -1962,13 +1963,6 @@ __must_hold(&the_lnet.ln_api_mutex)
        lnet_peer_ni_decref_locked(lpni);
        lp = lpni->lpni_peer_net->lpn_peer;
 
-       /* Peer must have been configured. */
-       if (!temp && !(lp->lp_state & LNET_PEER_CONFIGURED)) {
-               CDEBUG(D_NET, "peer %s was not configured\n",
-                      libcfs_nidstr(prim_nid));
-               return -ENOENT;
-       }
-
        /* Primary NID must match */
        if (!nid_same(&lp->lp_primary_nid, prim_nid)) {
                CDEBUG(D_NET, "prim_nid %s is not primary for peer %s\n",
@@ -1984,7 +1978,8 @@ __must_hold(&the_lnet.ln_api_mutex)
                return -EPERM;
        }
 
-       if (temp && lnet_peer_is_uptodate(lp)) {
+       if ((flags & LNET_PEER_LOCK_PRIMARY) &&
+           (lnet_peer_is_uptodate(lp) && (lp->lp_state & LNET_PEER_LOCK_PRIMARY))) {
                CDEBUG(D_NET,
                       "Don't add temporary peer NI for uptodate peer %s\n",
                       libcfs_nidstr(&lp->lp_primary_nid));
@@ -1994,6 +1989,11 @@ __must_hold(&the_lnet.ln_api_mutex)
        return lnet_peer_add_nid(lp, nid, flags);
 }
 
+int lnet_user_add_peer_ni(struct lnet_nid *prim_nid, struct lnet_nid *nid, bool mr)
+{
+       return lnet_add_peer_ni(prim_nid, nid, mr, LNET_PEER_CONFIGURED);
+}
+
 /*
  * Implementation of IOC_LIBCFS_DEL_PEER_NI.
  *