struct ovsdb *db;
uint64_t n_transactions; /* Count number of committed transactions. */
struct hmap_node hmap_node; /* Elements within ovsdb_monitors. */
+ struct hmap json_cache; /* Contains "ovsdb_monitor_json_cache_node"s.*/
+};
+
+/* A json object of updates between 'from_txn' and 'dbmon->n_transactions'
+ * inclusive. */
+struct ovsdb_monitor_json_cache_node {
+ struct hmap_node hmap_node; /* Elements in json cache. */
+ uint64_t from_txn;
+ struct json *json; /* Null, or a cloned of json */
};
struct jsonrpc_monitor_node {
static void ovsdb_monitor_table_track_changes(struct ovsdb_monitor_table *mt,
uint64_t unflushed);
+static struct ovsdb_monitor_json_cache_node *
+ovsdb_monitor_json_cache_search(const struct ovsdb_monitor *dbmon,
+ uint64_t from_txn)
+{
+ struct ovsdb_monitor_json_cache_node *node;
+ uint32_t hash = hash_uint64(from_txn);
+
+ HMAP_FOR_EACH_WITH_HASH(node, hmap_node, hash, &dbmon->json_cache) {
+ if (node->from_txn == from_txn) {
+ return node;
+ }
+ }
+
+ return NULL;
+}
+
+static void
+ovsdb_monitor_json_cache_insert(struct ovsdb_monitor *dbmon,
+ uint64_t from_txn, struct json *json)
+{
+ struct ovsdb_monitor_json_cache_node *node;
+ uint32_t hash;
+
+ node = xmalloc(sizeof *node);
+
+ hash = hash_uint64(from_txn);
+ node->from_txn = from_txn;
+ node->json = json ? json_clone(json) : NULL;
+
+ hmap_insert(&dbmon->json_cache, &node->hmap_node, hash);
+}
+
+static void
+ovsdb_monitor_json_cache_flush(struct ovsdb_monitor *dbmon)
+{
+ struct ovsdb_monitor_json_cache_node *node, *next;
+
+ HMAP_FOR_EACH_SAFE(node, next, hmap_node, &dbmon->json_cache) {
+ hmap_remove(&dbmon->json_cache, &node->hmap_node);
+ json_destroy(node->json);
+ free(node);
+ }
+}
+
static int
compare_ovsdb_monitor_column(const void *a_, const void *b_)
{
dbmon->n_transactions = 0;
shash_init(&dbmon->tables);
hmap_node_nullify(&dbmon->hmap_node);
+ hmap_init(&dbmon->json_cache);
ovsdb_monitor_add_jsonrpc_monitor(dbmon, jsonrpc_monitor);
return dbmon;
}
/* Constructs and returns JSON for a <table-updates> object (as described in
- * RFC 7047) for all the outstanding changes within 'monitor', and deletes all
- * the outstanding changes from 'monitor'. Returns NULL if no update needs to
- * be sent.
- *
- * The caller should specify 'initial' as true if the returned JSON is going to
- * be used as part of the initial reply to a "monitor" request, false if it is
- * going to be used as part of an "update" notification.
- *
- * 'unflushed' should point to value that is the transaction ID that did
- * was not updated. The update contains changes between
- * ['unflushed, ovsdb->n_transcations]. Before the function returns, this
- * value will be updated to ovsdb->n_transactions + 1, ready for the next
- * update. */
-struct json *
-ovsdb_monitor_compose_update(const struct ovsdb_monitor *dbmon,
- bool initial, uint64_t *unflushed)
+ * RFC 7047) for all the outstanding changes within 'monitor', starting from
+ * 'transaction'. */
+static struct json*
+ovsdb_monitor_compose_update(struct ovsdb_monitor *dbmon,
+ bool initial, uint64_t transaction)
{
struct shash_node *node;
unsigned long int *changed;
struct json *json;
size_t max_columns;
- uint64_t prev_txn = *unflushed;
- uint64_t next_txn = dbmon->n_transactions + 1;
max_columns = 0;
SHASH_FOR_EACH (node, &dbmon->tables) {
struct ovsdb_monitor_changes *changes;
struct json *table_json = NULL;
- changes = ovsdb_monitor_table_find_changes(mt, prev_txn);
+ changes = ovsdb_monitor_table_find_changes(mt, transaction);
if (!changes) {
- ovsdb_monitor_table_track_changes(mt, next_txn);
continue;
}
json_object_put(table_json, uuid, row_json);
}
}
+ }
+ free(changed);
+
+ return json;
+}
+
+/* Returns JSON for a <table-updates> object (as described in RFC 7047)
+ * for all the outstanding changes within 'monitor' that starts from
+ * '*unflushed' transaction id.
+ *
+ * The caller should specify 'initial' as true if the returned JSON is going to
+ * be used as part of the initial reply to a "monitor" request, false if it is
+ * 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)
+{
+ 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;
+
+ /* 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);
+ if (cache_node) {
+ json = cache_node->json ? json_clone(cache_node->json) : NULL;
+ } else {
+ json = ovsdb_monitor_compose_update(dbmon, initial, prev_txn);
+ ovsdb_monitor_json_cache_insert(dbmon, prev_txn, 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);
}
-
*unflushed = next_txn;
- free(changed);
+
return json;
}
hmap_remove(&ovsdb_monitors, &dbmon->hmap_node);
}
+ ovsdb_monitor_json_cache_flush(dbmon);
+ hmap_destroy(&dbmon->json_cache);
+
SHASH_FOR_EACH (node, &dbmon->tables) {
struct ovsdb_monitor_table *mt = node->data;
struct ovsdb_monitor_changes *changes, *next;
struct ovsdb_monitor *m = ovsdb_monitor_cast(replica);
struct ovsdb_monitor_aux aux;
+ ovsdb_monitor_json_cache_flush(m);
ovsdb_monitor_init_aux(&aux, m);
ovsdb_txn_for_each_change(txn, ovsdb_monitor_change_cb, &aux);
m->n_transactions++;
projects / cascardo / ovs.git / blobdiff