STATE(CONNECT_IN_PROGRESS, 1 << 3) \
STATE(ACTIVE, 1 << 4) \
STATE(IDLE, 1 << 5) \
- STATE(RECONNECT, 1 << 6)
+ STATE(RECONNECT, 1 << 6) \
+ STATE(LISTENING, 1 << 7)
enum state {
#define STATE(NAME, VALUE) S_##NAME = VALUE,
STATES
int min_backoff;
int max_backoff;
int probe_interval;
+ bool passive;
/* State. */
enum state state;
fsm->min_backoff = 1000;
fsm->max_backoff = 8000;
fsm->probe_interval = 5000;
+ fsm->passive = false;
fsm->state = S_VOID;
fsm->state_entered = now;
fsm->probe_interval = probe_interval ? MAX(1000, probe_interval) : 0;
}
+/* Returns true if 'fsm' is in passive mode, false if 'fsm' is in active mode
+ * (the default). */
+bool
+reconnect_is_passive(const struct reconnect *fsm)
+{
+ return fsm->passive;
+}
+
+/* Configures 'fsm' for active or passive mode. In active mode (the default),
+ * the FSM is attempting to connect to a remote host. In passive mode, the FSM
+ * is listening for connections from a remote host. */
+void
+reconnect_set_passive(struct reconnect *fsm, bool passive, long long int now)
+{
+ if (fsm->passive != passive) {
+ fsm->passive = passive;
+
+ if (passive
+ ? fsm->state & (S_CONNECT_IN_PROGRESS | S_RECONNECT)
+ : fsm->state == S_LISTENING && reconnect_may_retry(fsm)) {
+ reconnect_transition__(fsm, now, S_BACKOFF);
+ fsm->backoff = 0;
+ }
+ }
+}
+
/* Returns true if 'fsm' has been enabled with reconnect_enable(). Calling
* another function that indicates a change in connection state, such as
* reconnect_disconnected() or reconnect_force_reconnect(), will also enable
} else {
VLOG_INFO("%s: connection dropped", fsm->name);
}
- } else {
+ } else if (fsm->state == S_LISTENING) {
if (error > 0) {
- VLOG_WARN("%s: connection attempt failed (%s)",
+ VLOG_WARN("%s: error listening for connections (%s)",
fsm->name, strerror(error));
} else {
- VLOG_INFO("%s: connection attempt timed out", fsm->name);
+ VLOG_INFO("%s: error listening for connections", fsm->name);
+ }
+ } else {
+ const char *type = fsm->passive ? "listen" : "connection";
+ if (error > 0) {
+ VLOG_WARN("%s: %s attempt failed (%s)",
+ fsm->name, type, strerror(error));
+ } else {
+ VLOG_INFO("%s: %s attempt timed out", fsm->name, type);
}
}
/* Back off. */
if (fsm->state & (S_ACTIVE | S_IDLE)
- && fsm->last_received - fsm->last_connected >= fsm->backoff) {
- fsm->backoff = fsm->min_backoff;
+ && (fsm->last_received - fsm->last_connected >= fsm->backoff
+ || fsm->passive)) {
+ fsm->backoff = fsm->passive ? 0 : fsm->min_backoff;
} else {
if (fsm->backoff < fsm->min_backoff) {
fsm->backoff = fsm->min_backoff;
} else {
fsm->backoff *= 2;
}
- VLOG_INFO("%s: waiting %.3g seconds before reconnect\n",
- fsm->name, fsm->backoff / 1000.0);
+ if (fsm->passive) {
+ VLOG_INFO("%s: waiting %.3g seconds before trying to "
+ "listen again", fsm->name, fsm->backoff / 1000.0);
+ } else {
+ VLOG_INFO("%s: waiting %.3g seconds before reconnect",
+ fsm->name, fsm->backoff / 1000.0);
+ }
}
reconnect_transition__(fsm, now,
}
}
-/* Tell 'fsm' that a connection attempt is in progress.
+/* Tell 'fsm' that a connection or listening attempt is in progress.
*
- * The FSM will start a timer, after which the connection attempt will be
- * aborted (by returning RECONNECT_DISCONNECT from reconect_run()). */
+ * The FSM will start a timer, after which the connection or listening attempt
+ * will be aborted (by returning RECONNECT_DISCONNECT from reconect_run()). */
void
reconnect_connecting(struct reconnect *fsm, long long int now)
{
if (fsm->state != S_CONNECT_IN_PROGRESS) {
- VLOG_INFO("%s: connecting...", fsm->name);
+ if (fsm->passive) {
+ VLOG_INFO("%s: listening...", fsm->name);
+ } else {
+ VLOG_INFO("%s: connecting...", fsm->name);
+ }
reconnect_transition__(fsm, now, S_CONNECT_IN_PROGRESS);
}
}
+/* Tell 'fsm' that the client is listening for connection attempts. This state
+ * last indefinitely until the client reports some change.
+ *
+ * The natural progression from this state is for the client to report that a
+ * connection has been accepted or is in progress of being accepted, by calling
+ * reconnect_connecting() or reconnect_connected().
+ *
+ * The client may also report that listening failed (e.g. accept() returned an
+ * unexpected error such as ENOMEM) by calling reconnect_listen_error(), in
+ * which case the FSM will back off and eventually return RECONNECT_CONNECT
+ * from reconnect_run() to tell the client to try listening again. */
+void
+reconnect_listening(struct reconnect *fsm, long long int now)
+{
+ if (fsm->state != S_LISTENING) {
+ VLOG_INFO("%s: listening...", fsm->name);
+ reconnect_transition__(fsm, now, S_LISTENING);
+ }
+}
+
+/* Tell 'fsm' that the client's attempt to accept a connection failed
+ * (e.g. accept() returned an unexpected error such as ENOMEM).
+ *
+ * If the FSM is currently listening (reconnect_listening() was called), it
+ * will back off and eventually return RECONNECT_CONNECT from reconnect_run()
+ * to tell the client to try listening again. If there is an active
+ * connection, this will be delayed until that connection drops. */
+void
+reconnect_listen_error(struct reconnect *fsm, long long int now, int error)
+{
+ if (fsm->state == S_LISTENING) {
+ reconnect_disconnected(fsm, now, error);
+ }
+}
+
/* Tell 'fsm' that the connection was successful.
*
* The FSM will start the probe interval timer, which is reset by
assert(fsm->state_entered != LLONG_MIN);
switch (fsm->state) {
case S_VOID:
+ case S_LISTENING:
return LLONG_MAX;
case S_BACKOFF:
*
* - 0: The client need not take any action.
*
- * - RECONNECT_CONNECT: The client should start a connection attempt and
- * indicate this by calling reconnect_connecting(). If the connection
- * attempt has definitely succeeded, it should call
+ * - Active client, RECONNECT_CONNECT: The client should start a connection
+ * attempt and indicate this by calling reconnect_connecting(). If the
+ * connection attempt has definitely succeeded, it should call
* reconnect_connected(). If the connection attempt has definitely
* failed, it should call reconnect_connect_failed().
*
* (e.g. connect()) even if the connection might soon abort due to a
* failure at a high-level (e.g. SSL negotiation failure).
*
+ * - Passive client, RECONNECT_CONNECT: The client should try to listen for
+ * a connection, if it is not already listening. It should call
+ * reconnect_listening() if successful, otherwise reconnect_connecting()
+ * or reconnected_connect_failed() if the attempt is in progress or
+ * definitely failed, respectively.
+ *
+ * A listening passive client should constantly attempt to accept a new
+ * connection and report an accepted connection with
+ * reconnect_connected().
+ *
* - RECONNECT_DISCONNECT: The client should abort the current connection
- * or connection attempt and call reconnect_disconnected() or
- * reconnect_connect_failed() to indicate it.
+ * or connection attempt or listen attempt and call
+ * reconnect_disconnected() or reconnect_connect_failed() to indicate it.
*
* - RECONNECT_PROBE: The client should send some kind of request to the
* peer that will elicit a response, to ensure that the connection is
case S_RECONNECT:
return RECONNECT_DISCONNECT;
+
+ case S_LISTENING:
+ return 0;
}
NOT_REACHED();
no timeout
])
AT_CLEANUP
+
+######################################################################
+AT_SETUP([passive mode])
+AT_KEYWORDS([reconnect])
+AT_DATA([input], [passive
+enable
+
+# Start listening.
+timeout
+run
+listening
+
+# Listening never times out.
+timeout
+run
+
+# Listening failed (accept() returned funny error?). Back off and try again.
+listen-error 0
+timeout
+run
+listening
+
+# Connection accepted.
+connected
+received
+advance 1000
+received
+
+# Connection times out.
+timeout
+run
+timeout
+run
+disconnected
+
+# Start listening again.
+timeout
+run
+listening
+])
+AT_CHECK([test-reconnect < input], [0],
+ [### t=1000 ###
+passive
+enable
+ in BACKOFF for 0 ms (0 ms backoff)
+
+# Start listening.
+timeout
+ advance 0 ms
+run
+ should connect
+listening
+ in LISTENING for 0 ms (0 ms backoff)
+
+# Listening never times out.
+timeout
+ no timeout
+run
+
+# Listening failed (accept() returned funny error?). Back off and try again.
+listen-error 0
+ in BACKOFF for 0 ms (1000 ms backoff)
+timeout
+ advance 1000 ms
+
+### t=2000 ###
+ in BACKOFF for 1000 ms (1000 ms backoff)
+run
+ should connect
+listening
+ in LISTENING for 0 ms (1000 ms backoff)
+
+# Connection accepted.
+connected
+ in ACTIVE for 0 ms (1000 ms backoff)
+ created 1000, last received 1000, last connected 2000
+ 1 successful connections out of 1 attempts, seqno 1
+ connected (0 ms), total 0 ms connected
+received
+ created 1000, last received 2000, last connected 2000
+advance 1000
+
+### t=3000 ###
+ in ACTIVE for 1000 ms (1000 ms backoff)
+ connected (1000 ms), total 1000 ms connected
+received
+ created 1000, last received 3000, last connected 2000
+
+# Connection times out.
+timeout
+ advance 5000 ms
+
+### t=8000 ###
+ in ACTIVE for 6000 ms (1000 ms backoff)
+ connected (6000 ms), total 6000 ms connected
+run
+ should send probe
+ in IDLE for 0 ms (1000 ms backoff)
+timeout
+ advance 5000 ms
+
+### t=13000 ###
+ in IDLE for 5000 ms (1000 ms backoff)
+ connected (11000 ms), total 11000 ms connected
+run
+ should disconnect
+disconnected
+ in BACKOFF for 0 ms (0 ms backoff)
+ 1 successful connections out of 1 attempts, seqno 2
+ not connected (0 ms), total 11000 ms connected
+
+# Start listening again.
+timeout
+ advance 0 ms
+run
+ should connect
+listening
+ in LISTENING for 0 ms (0 ms backoff)
+])
+AT_CLEANUP
}
}
+static void
+do_set_passive(int argc OVS_UNUSED, char *argv[] OVS_UNUSED)
+{
+ reconnect_set_passive(reconnect, true, now);
+}
+
+static void
+do_listening(int argc OVS_UNUSED, char *argv[] OVS_UNUSED)
+{
+ reconnect_listening(reconnect, now);
+}
+
+static void
+do_listen_error(int argc OVS_UNUSED, char *argv[])
+{
+ reconnect_listen_error(reconnect, now, atoi(argv[1]));
+}
+
static const struct command commands[] = {
{ "enable", 0, 0, do_enable },
{ "disable", 0, 0, do_disable },
{ "advance", 1, 1, do_advance },
{ "timeout", 0, 0, do_timeout },
{ "set-max-tries", 1, 1, do_set_max_tries },
+ { "passive", 0, 0, do_set_passive },
+ { "listening", 0, 0, do_listening },
+ { "listen-error", 1, 1, do_listen_error },
{ NULL, 0, 0, NULL },
};
projects / openvswitch / commitdiff