Describe dummy test model. Work on OpenFlow intro.

[openvswitch] / lib / jsonrpc.c

diff --git a/lib/jsonrpc.c b/lib/jsonrpc.c
index fc8a75b08af1fbfe6694e36e2d4ecb514c515763..552de04c0771d2620b85f9613ddb8be2283c9526 100644 (file)
--- a/lib/jsonrpc.c
+++ b/lib/jsonrpc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -178,6 +178,14 @@ jsonrpc_get_backlog(const struct jsonrpc *rpc)
     return rpc->status ? 0 : rpc->backlog;
 }
 
+/* Returns the number of bytes that have been received on 'rpc''s underlying
+ * stream.  (The value wraps around if it exceeds UINT_MAX.) */
+unsigned int
+jsonrpc_get_received_bytes(const struct jsonrpc *rpc)
+{
+    return rpc->input.head;
+}
+
 /* Returns 'rpc''s name, that is, the name returned by stream_get_name() for
  * the stream underlying 'rpc' when 'rpc' was created. */
 const char *
@@ -277,13 +285,19 @@ jsonrpc_send(struct jsonrpc *rpc, struct jsonrpc_msg *msg)
 int
 jsonrpc_recv(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
 {
+    int i;
+
     *msgp = NULL;
     if (rpc->status) {
         return rpc->status;
     }
 
-    while (!rpc->received) {
-        if (byteq_is_empty(&rpc->input)) {
+    for (i = 0; i < 50; i++) {
+        if (rpc->received) {
+            *msgp = rpc->received;
+            rpc->received = NULL;
+            return 0;
+        } else if (byteq_is_empty(&rpc->input)) {
             size_t chunk;
             int retval;
 
@@ -328,9 +342,7 @@ jsonrpc_recv(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
         }
     }
 
-    *msgp = rpc->received;
-    rpc->received = NULL;
-    return 0;
+    return EAGAIN;
 }
 
 /* Causes the poll loop to wake up when jsonrpc_recv() may return a value other
@@ -779,7 +791,7 @@ jsonrpc_session_open(const char *name)
  * On the assumption that such connections are likely to be short-lived
  * (e.g. from ovs-vsctl), informational logging for them is suppressed. */
 struct jsonrpc_session *
-jsonrpc_session_open_unreliably(struct jsonrpc *jsonrpc)
+jsonrpc_session_open_unreliably(struct jsonrpc *jsonrpc, uint8_t dscp)
 {
     struct jsonrpc_session *s;
 
@@ -789,6 +801,7 @@ jsonrpc_session_open_unreliably(struct jsonrpc *jsonrpc)
     reconnect_set_name(s->reconnect, jsonrpc_get_name(jsonrpc));
     reconnect_set_max_tries(s->reconnect, 0);
     reconnect_connected(s->reconnect, time_msec());
+    s->dscp = dscp;
     s->rpc = jsonrpc;
     s->stream = NULL;
     s->pstream = NULL;
@@ -875,9 +888,23 @@ jsonrpc_session_run(struct jsonrpc_session *s)
     }
 
     if (s->rpc) {
+        size_t backlog;
         int error;
 
+        backlog = jsonrpc_get_backlog(s->rpc);
         jsonrpc_run(s->rpc);
+        if (jsonrpc_get_backlog(s->rpc) < backlog) {
+            /* Data previously caught in a queue was successfully sent (or
+             * there's an error, which we'll catch below.)
+             *
+             * We don't count data that is successfully sent immediately as
+             * activity, because there's a lot of queuing downstream from us,
+             * which means that we can push a lot of data into a connection
+             * that has stalled and won't ever recover.
+             */
+            reconnect_activity(s->reconnect, time_msec());
+        }
+
         error = jsonrpc_get_status(s->rpc);
         if (error) {
             reconnect_disconnected(s->reconnect, time_msec(), error);
@@ -969,10 +996,21 @@ struct jsonrpc_msg *
 jsonrpc_session_recv(struct jsonrpc_session *s)
 {
     if (s->rpc) {
+        unsigned int received_bytes;
         struct jsonrpc_msg *msg;
+
+        received_bytes = jsonrpc_get_received_bytes(s->rpc);
         jsonrpc_recv(s->rpc, &msg);
+        if (received_bytes != jsonrpc_get_received_bytes(s->rpc)) {
+            /* Data was successfully received.
+             *
+             * Previously we only counted receiving a full message as activity,
+             * but with large messages or a slow connection that policy could
+             * time out the session mid-message. */
+            reconnect_activity(s->reconnect, time_msec());
+        }
+
         if (msg) {
-            reconnect_received(s->reconnect, time_msec());
             if (msg->type == JSONRPC_REQUEST && !strcmp(msg->method, "echo")) {
                 /* Echo request.  Send reply. */
                 struct jsonrpc_msg *reply;
@@ -1054,5 +1092,22 @@ void
 jsonrpc_session_set_dscp(struct jsonrpc_session *s,
                          uint8_t dscp)
 {
-    s->dscp = dscp;
+    if (s->dscp != dscp) {
+        if (s->pstream) {
+            int error;
+
+            error = pstream_set_dscp(s->pstream, dscp);
+            if (error) {
+                VLOG_ERR("%s: failed set_dscp %s",
+                         reconnect_get_name(s->reconnect), strerror(error));
+            }
+            /*
+             * TODO:XXX race window between setting dscp to listening socket
+             * and accepting socket. accepted socket may have old dscp value.
+             * Ignore this race window for now.
+             */
+        }
+        s->dscp = dscp;
+        jsonrpc_session_force_reconnect(s);
+    }
 }