ovsdb: avoid unnecessary call to ovsdb_monitor_get_update()

[cascardo/ovs.git] / ovsdb / jsonrpc-server.c

diff --git a/ovsdb/jsonrpc-server.c b/ovsdb/jsonrpc-server.c
index 0f7932e..6f46dbc 100644 (file)
--- a/ovsdb/jsonrpc-server.c
+++ b/ovsdb/jsonrpc-server.c
@@ -22,6 +22,7 @@
 #include "bitmap.h"
 #include "column.h"
 #include "dynamic-string.h"
+#include "monitor.h"
 #include "json.h"
 #include "jsonrpc.h"
 #include "ovsdb-error.h"
@@ -37,7 +38,6 @@
 #include "timeval.h"
 #include "transaction.h"
 #include "trigger.h"
-#include "monitor.h"
 #include "openvswitch/vlog.h"
 
 VLOG_DEFINE_THIS_MODULE(ovsdb_jsonrpc_server);
@@ -45,6 +45,10 @@ VLOG_DEFINE_THIS_MODULE(ovsdb_jsonrpc_server);
 struct ovsdb_jsonrpc_remote;
 struct ovsdb_jsonrpc_session;
 
+/* Set false to defeature monitor2, causing jsonrpc to respond to monitor2
+ * method with an error.  */
+static bool monitor2_enable__ = true;
+
 /* Message rate-limiting. */
 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
 
@@ -81,7 +85,7 @@ static void ovsdb_jsonrpc_trigger_complete_done(
 /* Monitors. */
 static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_create(
     struct ovsdb_jsonrpc_session *, struct ovsdb *, struct json *params,
-    const struct json *request_id);
+    enum ovsdb_monitor_version, const struct json *request_id);
 static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_cancel(
     struct ovsdb_jsonrpc_session *,
     struct json_array *params,
@@ -97,7 +101,7 @@ static struct json *ovsdb_jsonrpc_monitor_compose_update(
 
 struct ovsdb_jsonrpc_server {
     struct ovsdb_server up;
-    unsigned int n_sessions, max_sessions;
+    unsigned int n_sessions;
     struct shash remotes;      /* Contains "struct ovsdb_jsonrpc_remote *"s. */
 };
 
@@ -126,7 +130,6 @@ ovsdb_jsonrpc_server_create(void)
 {
     struct ovsdb_jsonrpc_server *server = xzalloc(sizeof *server);
     ovsdb_server_init(&server->up);
-    server->max_sessions = 330;   /* Random limit. */
     shash_init(&server->remotes);
     return server;
 }
@@ -320,25 +323,19 @@ ovsdb_jsonrpc_server_run(struct ovsdb_jsonrpc_server *svr)
         struct ovsdb_jsonrpc_remote *remote = node->data;
 
         if (remote->listener) {
-            if (svr->n_sessions < svr->max_sessions) {
-                struct stream *stream;
-                int error;
-
-                error = pstream_accept(remote->listener, &stream);
-                if (!error) {
-                    struct jsonrpc_session *js;
-                    js = jsonrpc_session_open_unreliably(jsonrpc_open(stream),
-                                                         remote->dscp);
-                    ovsdb_jsonrpc_session_create(remote, js);
-                } else if (error != EAGAIN) {
-                    VLOG_WARN_RL(&rl, "%s: accept failed: %s",
-                                 pstream_get_name(remote->listener),
-                                 ovs_strerror(error));
-                }
-            } else {
-                VLOG_WARN_RL(&rl, "%s: connection exceeded maximum (%d)",
+            struct stream *stream;
+            int error;
+
+            error = pstream_accept(remote->listener, &stream);
+            if (!error) {
+                struct jsonrpc_session *js;
+                js = jsonrpc_session_open_unreliably(jsonrpc_open(stream),
+                                                     remote->dscp);
+                ovsdb_jsonrpc_session_create(remote, js);
+            } else if (error != EAGAIN) {
+                VLOG_WARN_RL(&rl, "%s: accept failed: %s",
                              pstream_get_name(remote->listener),
-                             svr->max_sessions);
+                             ovs_strerror(error));
             }
         }
 
@@ -354,7 +351,7 @@ ovsdb_jsonrpc_server_wait(struct ovsdb_jsonrpc_server *svr)
     SHASH_FOR_EACH (node, &svr->remotes) {
         struct ovsdb_jsonrpc_remote *remote = node->data;
 
-        if (remote->listener && svr->n_sessions < svr->max_sessions) {
+        if (remote->listener) {
             pstream_wait(remote->listener);
         }
 
@@ -529,7 +526,6 @@ ovsdb_jsonrpc_session_get_memory_usage(const struct ovsdb_jsonrpc_session *s,
                                        struct simap *usage)
 {
     simap_increase(usage, "triggers", hmap_count(&s->triggers));
-    simap_increase(usage, "monitors", hmap_count(&s->monitors));
     simap_increase(usage, "backlog", jsonrpc_session_get_backlog(s->js));
 }
 
@@ -844,11 +840,15 @@ ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *s,
         if (!reply) {
             reply = execute_transaction(s, db, request);
         }
-    } else if (!strcmp(request->method, "monitor")) {
+    } else if (!strcmp(request->method, "monitor") ||
+               (monitor2_enable__ && !strcmp(request->method, "monitor2"))) {
         struct ovsdb *db = ovsdb_jsonrpc_lookup_db(s, request, &reply);
         if (!reply) {
+            int l = strlen(request->method) - strlen("monitor");
+            enum ovsdb_monitor_version version = l ? OVSDB_MONITOR_V2
+                                                   : OVSDB_MONITOR_V1;
             reply = ovsdb_jsonrpc_monitor_create(s, db, request->params,
-                                                 request->id);
+                                                 version, request->id);
         }
     } else if (!strcmp(request->method, "monitor_cancel")) {
         reply = ovsdb_jsonrpc_monitor_cancel(s, json_array(request->params),
@@ -1039,6 +1039,7 @@ struct ovsdb_jsonrpc_monitor {
     struct ovsdb_monitor *dbmon;
     uint64_t unflushed;         /* The first transaction that has not been
                                        flushed to the jsonrpc remote client. */
+    enum ovsdb_monitor_version version;
 };
 
 static struct ovsdb_jsonrpc_monitor *
@@ -1154,6 +1155,7 @@ ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_monitor *dbmon,
 static struct jsonrpc_msg *
 ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
                              struct json *params,
+                             enum ovsdb_monitor_version version,
                              const struct json *request_id)
 {
     struct ovsdb_jsonrpc_monitor *m = NULL;
@@ -1185,6 +1187,7 @@ ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
     m->db = db;
     m->dbmon = ovsdb_monitor_create(db, m);
     m->unflushed = 0;
+    m->version = version;
     hmap_insert(&s->monitors, &m->node, json_hash(monitor_id, 0));
     m->monitor_id = json_clone(monitor_id);
 
@@ -1294,7 +1297,12 @@ static struct json *
 ovsdb_jsonrpc_monitor_compose_update(struct ovsdb_jsonrpc_monitor *m,
                                      bool initial)
 {
-    return ovsdb_monitor_compose_update(m->dbmon, initial, &m->unflushed);
+    if (!ovsdb_monitor_needs_flush(m->dbmon, m->unflushed)) {
+        return NULL;
+    }
+
+    return ovsdb_monitor_get_update(m->dbmon, initial, &m->unflushed,
+                                    m->version);
 }
 
 static bool
@@ -1320,6 +1328,27 @@ ovsdb_jsonrpc_monitor_destroy(struct ovsdb_jsonrpc_monitor *m)
     free(m);
 }
 
+static struct jsonrpc_msg *
+ovsdb_jsonrpc_create_notify(const struct ovsdb_jsonrpc_monitor *m,
+                            struct json *params)
+{
+    const char *method;
+
+    switch(m->version) {
+    case OVSDB_MONITOR_V1:
+        method = "update";
+        break;
+    case OVSDB_MONITOR_V2:
+        method = "update2";
+        break;
+    case OVSDB_MONITOR_VERSION_MAX:
+    default:
+        OVS_NOT_REACHED();
+    }
+
+    return jsonrpc_create_notify(method, params);
+}
+
 static void
 ovsdb_jsonrpc_monitor_flush_all(struct ovsdb_jsonrpc_session *s)
 {
@@ -1334,8 +1363,15 @@ ovsdb_jsonrpc_monitor_flush_all(struct ovsdb_jsonrpc_session *s)
             struct json *params;
 
             params = json_array_create_2(json_clone(m->monitor_id), json);
-            msg = jsonrpc_create_notify("update", params);
+            msg = ovsdb_jsonrpc_create_notify(m, params);
             jsonrpc_session_send(s->js, msg);
         }
     }
 }
+
+void
+ovsdb_jsonrpc_disable_monitor2(void)
+{
+    /* Once disabled, it is not possible to re-enable it. */
+    monitor2_enable__ = false;
+}