The function tipc_nametbl_translate() function is ugly and hard to
follow. This can be improved somewhat by introducing a stack variable
for holding the publication list to be used and re-ordering the if-
clauses for selection of algorithm.
Signed-off-by: Jon Maloy <jon.ma...@ericsson.com>
---
net/tipc/name_table.c | 61 +++++++++++++++++++++------------------------------
1 file changed, 25 insertions(+), 36 deletions(-)
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index e06c7a8..4bdc580 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -399,29 +399,32 @@ struct publication *tipc_nametbl_remove_publ(struct net
*net, u32 type,
/**
* tipc_nametbl_translate - perform service instance to socket translation
*
- * On entry, 'destnode' is the search domain used during translation.
+ * On entry, 'dnode' is the search domain used during translation.
*
* On exit:
- * - if name translation is deferred to another node/cluster/zone,
- * leaves 'destnode' unchanged (will be non-zero) and returns 0
- * - if name translation is attempted and succeeds, sets 'destnode'
- * to publication node and returns port reference (will be non-zero)
- * - if name translation is attempted and fails, sets 'destnode' to 0
- * and returns 0
+ * - if translation is deferred to another node, leave 'dnode' unchanged and
+ * return 0
+ * - if translation is attempted and succeeds, set 'dnode' to the publishing
+ * node and return the published (non-zero) port number
+ * - if translation is attempted and fails, set 'dnode' to 0 and return 0
+ *
+ * Note that for legacy users (node configured with Z.C.N address format) the
+ * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
+ * we must look in the local binding list first
*/
-u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance,
- u32 *destnode)
+u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
{
struct tipc_net *tn = tipc_net(net);
bool legacy = tn->legacy_addr_format;
u32 self = tipc_own_addr(net);
struct service_range *sr;
struct tipc_service *sc;
+ struct list_head *list;
struct publication *p;
u32 port = 0;
u32 node = 0;
- if (!tipc_in_scope(legacy, *destnode, self))
+ if (!tipc_in_scope(legacy, *dnode, self))
return 0;
rcu_read_lock();
@@ -434,43 +437,29 @@ u32 tipc_nametbl_translate(struct net *net, u32 type, u32
instance,
if (unlikely(!sr))
goto no_match;
- /* Closest-First Algorithm */
- if (legacy && !*destnode) {
- if (!list_empty(&sr->local_publ)) {
- p = list_first_entry(&sr->local_publ,
- struct publication,
- local_publ);
- list_move_tail(&p->local_publ,
- &sr->local_publ);
- } else {
- p = list_first_entry(&sr->all_publ,
- struct publication,
- all_publ);
- list_move_tail(&p->all_publ,
- &sr->all_publ);
- }
- }
-
- /* Round-Robin Algorithm */
- else if (*destnode == self) {
- if (list_empty(&sr->local_publ))
+ /* Select lookup algorithm: local, closest-first or round-robin */
+ if (*dnode == self) {
+ list = &sr->local_publ;
+ if (list_empty(list))
goto no_match;
- p = list_first_entry(&sr->local_publ, struct publication,
- local_publ);
+ p = list_first_entry(list, struct publication, local_publ);
+ list_move_tail(&p->local_publ, &sr->local_publ);
+ } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
+ list = &sr->local_publ;
+ p = list_first_entry(list, struct publication, local_publ);
list_move_tail(&p->local_publ, &sr->local_publ);
} else {
- p = list_first_entry(&sr->all_publ, struct publication,
- all_publ);
+ list = &sr->all_publ;
+ p = list_first_entry(list, struct publication, all_publ);
list_move_tail(&p->all_publ, &sr->all_publ);
}
-
port = p->port;
node = p->node;
no_match:
spin_unlock_bh(&sc->lock);
not_found:
rcu_read_unlock();
- *destnode = node;
+ *dnode = node;
return port;
}
--
2.1.4
