From: Ben Pfaff <blp@nicira.com>
Date: Mon, 14 Jul 2008 20:31:28 +0000 (-0700)
Subject: rconn: Add new max_backoff argument to rconn_new().
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e334e4e0e775a431677bf54a5ece134167fe514d;p=openvswitch

rconn: Add new max_backoff argument to rconn_new().

This allows the caller more control over reconnection backoff.
---

diff --git a/include/rconn.h b/include/rconn.h
index 67356862..8f3b0acf 100644
--- a/include/rconn.h
+++ b/include/rconn.h
@@ -54,7 +54,7 @@
 struct vconn;
 
 struct rconn *rconn_new(const char *name, int txq_limit,
-                        int inactivity_probe_interval);
+                        int inactivity_probe_interval, int max_backoff);
 struct rconn *rconn_new_from_vconn(const char *name, int txq_limit,
                                    struct vconn *);
 void rconn_destroy(struct rconn *);
diff --git a/lib/rconn.c b/lib/rconn.c
index 8292401a..1668ad99 100644
--- a/lib/rconn.c
+++ b/lib/rconn.c
@@ -57,6 +57,7 @@ struct rconn {
     int txq_limit;
     time_t backoff_deadline;
     int backoff;
+    int max_backoff;
     time_t last_connected;
     unsigned int packets_sent;
 
@@ -70,7 +71,8 @@ struct rconn {
 };
 
 static struct rconn *create_rconn(const char *name, int txq_limit,
-                                  int probe_interval, struct vconn *);
+                                  int probe_interval, int max_backoff,
+                                  struct vconn *);
 static int try_send(struct rconn *);
 static void disconnect(struct rconn *, int error);
 static time_t probe_deadline(const struct rconn *);
@@ -84,11 +86,16 @@ static time_t probe_deadline(const struct rconn *);
  * without an OpenFlow message being received from the peer, the rconn sends
  * out an "echo request" message.  If the interval passes again without a
  * message being received, the rconn disconnects and re-connects to the peer.
- * Setting 'probe_interval' to 0 disables this behavior.  */
+ * Setting 'probe_interval' to 0 disables this behavior.
+ *
+ * 'max_backoff' is the maximum number of seconds between attempts to connect
+ * to the peer.  The actual interval starts at 1 second and doubles on each
+ * failure until it reaches 'max_backoff'.  If 0 is specified, the default of
+ * 60 seconds is used. */
 struct rconn *
-rconn_new(const char *name, int txq_limit, int probe_interval)
+rconn_new(const char *name, int txq_limit, int probe_interval, int max_backoff)
 {
-    return create_rconn(name, txq_limit, probe_interval, NULL);
+    return create_rconn(name, txq_limit, probe_interval, max_backoff, NULL);
 }
 
 /* Creates and returns a new rconn that is initially connected to 'vconn' and
@@ -100,7 +107,7 @@ struct rconn *
 rconn_new_from_vconn(const char *name, int txq_limit, struct vconn *vconn)
 {
     assert(vconn != NULL);
-    return create_rconn(name, txq_limit, 0, vconn);
+    return create_rconn(name, txq_limit, 0, 0, vconn);
 }
 
 /* Disconnects 'rc' and frees the underlying storage. */
@@ -335,7 +342,7 @@ rconn_get_ip(const struct rconn *rconn)
 
 static struct rconn *
 create_rconn(const char *name, int txq_limit, int probe_interval,
-             struct vconn *vconn)
+             int max_backoff, struct vconn *vconn)
 {
     struct rconn *rc = xmalloc(sizeof *rc);
     assert(txq_limit > 0);
@@ -347,6 +354,7 @@ create_rconn(const char *name, int txq_limit, int probe_interval,
     rc->txq_limit = txq_limit;
     rc->backoff_deadline = time(0);
     rc->backoff = 0;
+    rc->max_backoff = max_backoff ? max_backoff : 60;
     rc->last_connected = time(0);
     rc->probe_interval = (probe_interval
                               ? MAX(5, probe_interval) : 0);
@@ -398,7 +406,7 @@ disconnect(struct rconn *rc, int error)
     if (now >= rc->backoff_deadline) {
         rc->backoff = 1;
     } else {
-        rc->backoff = MIN(60, MAX(1, 2 * rc->backoff));
+        rc->backoff = MIN(rc->max_backoff, MAX(1, 2 * rc->backoff));
         VLOG_WARN("%s: waiting %d seconds before reconnect\n",
                   rc->name, rc->backoff);
     }
diff --git a/secchan/secchan.c b/secchan/secchan.c
index 80ba9870..c5793dd7 100644
--- a/secchan/secchan.c
+++ b/secchan/secchan.c
@@ -197,9 +197,9 @@ main(int argc, char *argv[])
 
     daemonize();
 
-    controller_relay = relay_create(rconn_new(argv[optind], 1, 0),
+    controller_relay = relay_create(rconn_new(argv[optind], 1, 0, 0),
                                     rconn_new(argv[optind + 1], 1,
-                                              probe_interval),
+                                              probe_interval, 0),
                                     false);
     for (;;) {
         struct relay *r, *n;
diff --git a/switch/switch.c b/switch/switch.c
index 5284fdb5..8a1f94e2 100644
--- a/switch/switch.c
+++ b/switch/switch.c
@@ -77,7 +77,7 @@ main(int argc, char *argv[])
         fatal(0, "missing controller argument; use --help for usage");
     }
 
-    error = dp_new(&dp, dpid, rconn_new(argv[optind], 128, 60));
+    error = dp_new(&dp, dpid, rconn_new(argv[optind], 128, 60, 0));
     if (listen_vconn_name) {
         struct vconn *listen_vconn;
         int retval;