ovsdb-server: Fix a reference count leak bug

[cascardo/ovs.git] / ovsdb / monitor.c

diff --git a/ovsdb/monitor.c b/ovsdb/monitor.c
index f08607a..6b0d13d 100644 (file)
--- a/ovsdb/monitor.c
+++ b/ovsdb/monitor.c
@@ -61,6 +61,7 @@ struct ovsdb_monitor {
  * inclusive.  */
 struct ovsdb_monitor_json_cache_node {
     struct hmap_node hmap_node;   /* Elements in json cache. */
+    enum ovsdb_monitor_version version;
     uint64_t from_txn;
     struct json *json;            /* Null, or a cloned of json */
 };
@@ -134,15 +135,27 @@ static void ovsdb_monitor_changes_destroy(
 static void ovsdb_monitor_table_track_changes(struct ovsdb_monitor_table *mt,
                                   uint64_t unflushed);
 
+static uint32_t
+json_cache_hash(enum ovsdb_monitor_version version, uint64_t from_txn)
+{
+    uint32_t hash;
+
+    hash = hash_uint64(version);
+    hash = hash_uint64_basis(from_txn, hash);
+
+    return hash;
+}
+
 static struct ovsdb_monitor_json_cache_node *
 ovsdb_monitor_json_cache_search(const struct ovsdb_monitor *dbmon,
+                                enum ovsdb_monitor_version version,
                                 uint64_t from_txn)
 {
     struct ovsdb_monitor_json_cache_node *node;
-    uint32_t hash = hash_uint64(from_txn);
+    uint32_t hash = json_cache_hash(version, from_txn);
 
     HMAP_FOR_EACH_WITH_HASH(node, hmap_node, hash, &dbmon->json_cache) {
-        if (node->from_txn == from_txn) {
+        if (node->from_txn == from_txn && node->version == version) {
             return node;
         }
     }
@@ -152,14 +165,15 @@ ovsdb_monitor_json_cache_search(const struct ovsdb_monitor *dbmon,
 
 static void
 ovsdb_monitor_json_cache_insert(struct ovsdb_monitor *dbmon,
+                                enum ovsdb_monitor_version version,
                                 uint64_t from_txn, struct json *json)
 {
     struct ovsdb_monitor_json_cache_node *node;
-    uint32_t hash;
+    uint32_t hash = json_cache_hash(version, from_txn);
 
     node = xmalloc(sizeof *node);
 
-    hash = hash_uint64(from_txn);
+    node->version = version;
     node->from_txn = from_txn;
     node->json = json ? json_clone(json) : NULL;
 
@@ -710,40 +724,40 @@ ovsdb_monitor_compose_update(struct ovsdb_monitor *dbmon,
  * going to be used as part of an "update" notification. */
 struct json *
 ovsdb_monitor_get_update(struct ovsdb_monitor *dbmon,
-                         bool initial, uint64_t *unflushed,
+                         bool initial, uint64_t *unflushed_,
                          enum ovsdb_monitor_version version)
 {
     struct ovsdb_monitor_json_cache_node *cache_node;
     struct shash_node *node;
     struct json *json;
-    uint64_t prev_txn = *unflushed;
-    uint64_t next_txn = dbmon->n_transactions + 1;
+    const uint64_t unflushed = *unflushed_;
+    const uint64_t next_unflushed = dbmon->n_transactions + 1;
 
     /* Return a clone of cached json if one exists. Otherwise,
      * generate a new one and add it to the cache.  */
-    cache_node = ovsdb_monitor_json_cache_search(dbmon, prev_txn);
+    cache_node = ovsdb_monitor_json_cache_search(dbmon, version, unflushed);
     if (cache_node) {
         json = cache_node->json ? json_clone(cache_node->json) : NULL;
     } else {
         if (version == OVSDB_MONITOR_V1) {
-            json = ovsdb_monitor_compose_update(dbmon, initial, prev_txn,
+            json = ovsdb_monitor_compose_update(dbmon, initial, unflushed,
                                         ovsdb_monitor_compose_row_update);
         } else {
             ovs_assert(version == OVSDB_MONITOR_V2);
-            json = ovsdb_monitor_compose_update(dbmon, initial, prev_txn,
+            json = ovsdb_monitor_compose_update(dbmon, initial, unflushed,
                                         ovsdb_monitor_compose_row_update2);
         }
-        ovsdb_monitor_json_cache_insert(dbmon, prev_txn, json);
+        ovsdb_monitor_json_cache_insert(dbmon, version, unflushed, json);
     }
 
     /* Maintain transaction id of 'changes'. */
     SHASH_FOR_EACH (node, &dbmon->tables) {
         struct ovsdb_monitor_table *mt = node->data;
 
-        ovsdb_monitor_table_untrack_changes(mt, prev_txn);
-        ovsdb_monitor_table_track_changes(mt, next_txn);
+        ovsdb_monitor_table_untrack_changes(mt, unflushed);
+        ovsdb_monitor_table_track_changes(mt, next_unflushed);
     }
-    *unflushed = next_txn;
+    *unflushed_ = next_unflushed;
 
     return json;
 }
@@ -945,7 +959,8 @@ ovsdb_monitor_get_initial(const struct ovsdb_monitor *dbmon)
 
 void
 ovsdb_monitor_remove_jsonrpc_monitor(struct ovsdb_monitor *dbmon,
-                   struct ovsdb_jsonrpc_monitor *jsonrpc_monitor)
+                   struct ovsdb_jsonrpc_monitor *jsonrpc_monitor,
+                   uint64_t unflushed)
 {
     struct jsonrpc_monitor_node *jm;
 
@@ -957,6 +972,12 @@ ovsdb_monitor_remove_jsonrpc_monitor(struct ovsdb_monitor *dbmon,
     /* Find and remove the jsonrpc monitor from the list.  */
     LIST_FOR_EACH(jm, node, &dbmon->jsonrpc_monitors) {
         if (jm->jsonrpc_monitor == jsonrpc_monitor) {
+            /* Release the tracked changes. */
+            struct shash_node *node;
+            SHASH_FOR_EACH (node, &dbmon->tables) {
+                struct ovsdb_monitor_table *mt = node->data;
+                ovsdb_monitor_table_untrack_changes(mt, unflushed);
+            }
             list_remove(&jm->node);
             free(jm);
 
@@ -1107,11 +1128,24 @@ ovsdb_monitor_commit(struct ovsdb_replica *replica,
     struct ovsdb_monitor_aux aux;
 
     ovsdb_monitor_init_aux(&aux, m);
+    /* Update ovsdb_monitor's transaction number for
+     * each transaction, before calling ovsdb_monitor_change_cb().  */
+    m->n_transactions++;
     ovsdb_txn_for_each_change(txn, ovsdb_monitor_change_cb, &aux);
 
-    if (aux.efficacy == OVSDB_CHANGES_REQUIRE_EXTERNAL_UPDATE) {
+    switch(aux.efficacy) {
+    case OVSDB_CHANGES_NO_EFFECT:
+        /* The transaction is ignored by the monitor.
+         * Roll back the 'n_transactions' as if the transaction
+         * has never happened. */
+        m->n_transactions--;
+        break;
+    case OVSDB_CHANGES_REQUIRE_INTERNAL_UPDATE:
+        /* Nothing.  */
+        break;
+    case  OVSDB_CHANGES_REQUIRE_EXTERNAL_UPDATE:
         ovsdb_monitor_json_cache_flush(m);
-        m->n_transactions++;
+        break;
     }
 
     return NULL;
@@ -1131,6 +1165,14 @@ ovsdb_monitor_destroy_callback(struct ovsdb_replica *replica)
     }
 }
 
+/* Add some memory usage statics for monitors into 'usage', for use with
+ * memory_report().  */
+void
+ovsdb_monitor_get_memory_usage(struct simap *usage)
+{
+    simap_put(usage, "monitors", hmap_count(&ovsdb_monitors));
+}
+
 static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class = {
     ovsdb_monitor_commit,
     ovsdb_monitor_destroy_callback,