LU-4423 lnet: fix deadloop in ksocknal_push

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

diff --git a/lnet/klnds/socklnd/socklnd.c b/lnet/klnds/socklnd/socklnd.c
index 816f836..1a1fa77 100644 (file)
--- a/lnet/klnds/socklnd/socklnd.c
+++ b/lnet/klnds/socklnd/socklnd.c
@@ -1896,50 +1896,50 @@ ksocknal_push_peer (ksock_peer_t *peer)
 static int
 ksocknal_push (lnet_ni_t *ni, lnet_process_id_t id)
 {
-        ksock_peer_t      *peer;
-       struct list_head        *tmp;
-        int                index;
-        int                i;
-        int                j;
-        int                rc = -ENOENT;
-
-        for (i = 0; i < ksocknal_data.ksnd_peer_hash_size; i++) {
-                for (j = 0; ; j++) {
-                       read_lock(&ksocknal_data.ksnd_global_lock);
+       struct list_head *start;
+       struct list_head *end;
+       struct list_head *tmp;
+       int               rc = -ENOENT;
+       unsigned int      hsize = ksocknal_data.ksnd_peer_hash_size;
 
-                        index = 0;
-                        peer = NULL;
+       if (id.nid == LNET_NID_ANY) {
+               start = &ksocknal_data.ksnd_peers[0];
+               end = &ksocknal_data.ksnd_peers[hsize - 1];
+       } else {
+               start = end = ksocknal_nid2peerlist(id.nid);
+       }
 
-                       list_for_each(tmp, &ksocknal_data.ksnd_peers[i]) {
-                               peer = list_entry(tmp, ksock_peer_t,
-                                                      ksnp_list);
+       for (tmp = start; tmp <= end; tmp++) {
+               int     peer_off; /* searching offset in peer hash table */
 
-                                if (!((id.nid == LNET_NID_ANY ||
-                                       id.nid == peer->ksnp_id.nid) &&
-                                      (id.pid == LNET_PID_ANY ||
-                                       id.pid == peer->ksnp_id.pid))) {
-                                        peer = NULL;
-                                        continue;
-                                }
+               for (peer_off = 0; ; peer_off++) {
+                       ksock_peer_t *peer;
+                       int           i = 0;
 
-                                if (index++ == j) {
-                                        ksocknal_peer_addref(peer);
-                                        break;
-                                }
-                        }
+                       read_lock(&ksocknal_data.ksnd_global_lock);
+                       list_for_each_entry(peer, tmp, ksnp_list) {
+                               if (!((id.nid == LNET_NID_ANY ||
+                                      id.nid == peer->ksnp_id.nid) &&
+                                     (id.pid == LNET_PID_ANY ||
+                                      id.pid == peer->ksnp_id.pid)))
+                                       continue;
 
+                               if (i++ == peer_off) {
+                                       ksocknal_peer_addref(peer);
+                                       break;
+                               }
+                       }
                        read_unlock(&ksocknal_data.ksnd_global_lock);
 
-                        if (peer != NULL) {
-                                rc = 0;
-                                ksocknal_push_peer (peer);
-                                ksocknal_peer_decref(peer);
-                        }
-                }
-
-        }
+                       if (i == 0) /* no match */
+                               break;
 
-        return (rc);
+                       rc = 0;
+                       ksocknal_push_peer(peer);
+                       ksocknal_peer_decref(peer);
+               }
+       }
+       return rc;
 }
 
 static int