LU-12678 lnet: discard ksnn_lock

[fs/lustre-release.git] / lnet / klnds / socklnd / socklnd.c

diff --git a/lnet/klnds/socklnd/socklnd.c b/lnet/klnds/socklnd/socklnd.c
index 30cbf3f..e3e037a 100644 (file)
--- a/lnet/klnds/socklnd/socklnd.c
+++ b/lnet/klnds/socklnd/socklnd.c
@@ -107,9 +107,16 @@ ksocknal_create_peer(struct lnet_ni *ni, struct lnet_process_id id)
        LASSERT(id.pid != LNET_PID_ANY);
        LASSERT(!in_interrupt());
 
+       if (!atomic_inc_unless_negative(&net->ksnn_npeers)) {
+               CERROR("Can't create peer_ni: network shutdown\n");
+               return ERR_PTR(-ESHUTDOWN);
+       }
+
        LIBCFS_CPT_ALLOC(peer_ni, lnet_cpt_table(), cpt, sizeof(*peer_ni));
-       if (peer_ni == NULL)
+       if (!peer_ni) {
+               atomic_dec(&net->ksnn_npeers);
                return ERR_PTR(-ENOMEM);
+       }
 
        peer_ni->ksnp_ni = ni;
        peer_ni->ksnp_id = id;
@@ -126,20 +133,6 @@ ksocknal_create_peer(struct lnet_ni *ni, struct lnet_process_id id)
        INIT_LIST_HEAD(&peer_ni->ksnp_zc_req_list);
        spin_lock_init(&peer_ni->ksnp_lock);
 
-       spin_lock_bh(&net->ksnn_lock);
-
-       if (net->ksnn_shutdown) {
-               spin_unlock_bh(&net->ksnn_lock);
-
-               LIBCFS_FREE(peer_ni, sizeof(*peer_ni));
-               CERROR("Can't create peer_ni: network shutdown\n");
-               return ERR_PTR(-ESHUTDOWN);
-       }
-
-       net->ksnn_npeers++;
-
-       spin_unlock_bh(&net->ksnn_lock);
-
        return peer_ni;
 }
 
@@ -160,13 +153,12 @@ ksocknal_destroy_peer(struct ksock_peer_ni *peer_ni)
 
        LIBCFS_FREE(peer_ni, sizeof(*peer_ni));
 
-        /* NB a peer_ni's connections and routes keep a reference on their peer_ni
-         * until they are destroyed, so we can be assured that _all_ state to
-         * do with this peer_ni has been cleaned up when its refcount drops to
-         * zero. */
-       spin_lock_bh(&net->ksnn_lock);
-       net->ksnn_npeers--;
-       spin_unlock_bh(&net->ksnn_lock);
+       /* NB a peer_ni's connections and routes keep a reference on their
+        * peer_ni until they are destroyed, so we can be assured that _all_
+        * state to do with this peer_ni has been cleaned up when its refcount
+        * drops to zero.
+        */
+       atomic_dec(&net->ksnn_npeers);
 }
 
 struct ksock_peer_ni *
@@ -469,7 +461,8 @@ ksocknal_add_peer(struct lnet_ni *ni, struct lnet_process_id id, __u32 ipaddr,
        write_lock_bh(&ksocknal_data.ksnd_global_lock);
 
         /* always called with a ref on ni, so shutdown can't have started */
-       LASSERT(((struct ksock_net *) ni->ni_data)->ksnn_shutdown == 0);
+       LASSERT(atomic_read(&((struct ksock_net *)ni->ni_data)->ksnn_npeers)
+               >= 0);
 
        peer2 = ksocknal_find_peer_locked(ni, id);
        if (peer2 != NULL) {
@@ -1133,7 +1126,7 @@ ksocknal_create_conn(struct lnet_ni *ni, struct ksock_route *route,
                write_lock_bh(global_lock);
 
                /* called with a ref on ni, so shutdown can't have started */
-               LASSERT(((struct ksock_net *) ni->ni_data)->ksnn_shutdown == 0);
+               LASSERT(atomic_read(&((struct ksock_net *)ni->ni_data)->ksnn_npeers) >= 0);
 
                peer2 = ksocknal_find_peer_locked(ni, peerid);
                if (peer2 == NULL) {
@@ -2522,39 +2515,32 @@ ksocknal_shutdown(struct lnet_ni *ni)
        };
        int i;
 
-        LASSERT(ksocknal_data.ksnd_init == SOCKNAL_INIT_ALL);
-        LASSERT(ksocknal_data.ksnd_nnets > 0);
+       LASSERT(ksocknal_data.ksnd_init == SOCKNAL_INIT_ALL);
+       LASSERT(ksocknal_data.ksnd_nnets > 0);
 
-       spin_lock_bh(&net->ksnn_lock);
-       net->ksnn_shutdown = 1;                 /* prevent new peers */
-       spin_unlock_bh(&net->ksnn_lock);
+       /* prevent new peers */
+       atomic_add(SOCKNAL_SHUTDOWN_BIAS, &net->ksnn_npeers);
 
        /* Delete all peers */
        ksocknal_del_peer(ni, anyid, 0);
 
        /* Wait for all peer_ni state to clean up */
        i = 2;
-       spin_lock_bh(&net->ksnn_lock);
-       while (net->ksnn_npeers != 0) {
-               spin_unlock_bh(&net->ksnn_lock);
-
+       while (atomic_read(&net->ksnn_npeers) > SOCKNAL_SHUTDOWN_BIAS) {
                i++;
                CDEBUG(((i & (-i)) == i) ? D_WARNING : D_NET, /* power of 2? */
                       "waiting for %d peers to disconnect\n",
-                      net->ksnn_npeers);
+                      atomic_read(&net->ksnn_npeers) - SOCKNAL_SHUTDOWN_BIAS);
                set_current_state(TASK_UNINTERRUPTIBLE);
                schedule_timeout(cfs_time_seconds(1));
 
                ksocknal_debug_peerhash(ni);
-
-               spin_lock_bh(&net->ksnn_lock);
        }
-       spin_unlock_bh(&net->ksnn_lock);
 
-        for (i = 0; i < net->ksnn_ninterfaces; i++) {
-                LASSERT (net->ksnn_interfaces[i].ksni_npeers == 0);
-                LASSERT (net->ksnn_interfaces[i].ksni_nroutes == 0);
-        }
+       for (i = 0; i < net->ksnn_ninterfaces; i++) {
+               LASSERT(net->ksnn_interfaces[i].ksni_npeers == 0);
+               LASSERT(net->ksnn_interfaces[i].ksni_nroutes == 0);
+       }
 
        list_del(&net->ksnn_list);
        LIBCFS_FREE(net, sizeof(*net));
@@ -2696,11 +2682,10 @@ ksocknal_startup(struct lnet_ni *ni)
                         return rc;
         }
 
-        LIBCFS_ALLOC(net, sizeof(*net));
-        if (net == NULL)
-                goto fail_0;
+       LIBCFS_ALLOC(net, sizeof(*net));
+       if (net == NULL)
+               goto fail_0;
 
-       spin_lock_init(&net->ksnn_lock);
        net->ksnn_incarnation = ktime_get_real_ns();
        ni->ni_data = net;
        net_tunables = &ni->ni_net->net_tunables;