2 * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
27 #include "openflow/openflow.h"
28 #include "poll-loop.h"
35 VLOG_DEFINE_THIS_MODULE(rconn);
37 COVERAGE_DEFINE(rconn_discarded);
38 COVERAGE_DEFINE(rconn_overflow);
39 COVERAGE_DEFINE(rconn_queued);
40 COVERAGE_DEFINE(rconn_sent);
44 STATE(BACKOFF, 1 << 1) \
45 STATE(CONNECTING, 1 << 2) \
46 STATE(ACTIVE, 1 << 3) \
49 #define STATE(NAME, VALUE) S_##NAME = VALUE,
55 state_name(enum state state)
58 #define STATE(NAME, VALUE) case S_##NAME: return #NAME;
65 /* A reliable connection to an OpenFlow switch or controller.
67 * See the large comment in rconn.h for more information. */
73 char *name; /* Human-readable descriptive name. */
74 char *target; /* vconn name, passed to vconn_open(). */
77 struct list txq; /* Contains "struct ofpbuf"s. */
81 time_t backoff_deadline;
83 time_t last_connected;
84 time_t last_disconnected;
85 unsigned int packets_sent;
89 /* In S_ACTIVE and S_IDLE, probably_admitted reports whether we believe
90 * that the peer has made a (positive) admission control decision on our
91 * connection. If we have not yet been (probably) admitted, then the
92 * connection does not reset the timer used for deciding whether the switch
93 * should go into fail-open mode.
95 * last_admitted reports the last time we believe such a positive admission
96 * control decision was made. */
97 bool probably_admitted;
100 /* These values are simply for statistics reporting, not used directly by
101 * anything internal to the rconn (or ofproto for that matter). */
102 unsigned int packets_received;
103 unsigned int n_attempted_connections, n_successful_connections;
104 time_t creation_time;
105 unsigned long int total_time_connected;
107 /* Throughout this file, "probe" is shorthand for "inactivity probe".
108 * When nothing has been received from the peer for a while, we send out
109 * an echo request as an inactivity probe packet. We should receive back
111 int probe_interval; /* Secs of inactivity before sending probe. */
113 /* When we create a vconn we obtain these values, to save them past the end
114 * of the vconn's lifetime. Otherwise, in-band control will only allow
115 * traffic when a vconn is actually open, but it is nice to allow ARP to
116 * complete even between connection attempts, and it is also polite to
117 * allow traffic from other switches to go through to the controller
118 * whether or not we are connected.
120 * We don't cache the local port, because that changes from one connection
121 * attempt to the next. */
122 ovs_be32 local_ip, remote_ip;
123 ovs_be16 remote_port;
126 /* Messages sent or received are copied to the monitor connections. */
127 #define MAX_MONITORS 8
128 struct vconn *monitors[8];
132 static unsigned int elapsed_in_this_state(const struct rconn *);
133 static unsigned int timeout(const struct rconn *);
134 static bool timed_out(const struct rconn *);
135 static void state_transition(struct rconn *, enum state);
136 static void rconn_set_target__(struct rconn *,
137 const char *target, const char *name);
138 static int try_send(struct rconn *);
139 static void reconnect(struct rconn *);
140 static void report_error(struct rconn *, int error);
141 static void disconnect(struct rconn *, int error);
142 static void flush_queue(struct rconn *);
143 static void copy_to_monitor(struct rconn *, const struct ofpbuf *);
144 static bool is_connected_state(enum state);
145 static bool is_admitted_msg(const struct ofpbuf *);
146 static bool rconn_logging_connection_attempts__(const struct rconn *);
148 /* Creates and returns a new rconn.
150 * 'probe_interval' is a number of seconds. If the interval passes once
151 * without an OpenFlow message being received from the peer, the rconn sends
152 * out an "echo request" message. If the interval passes again without a
153 * message being received, the rconn disconnects and re-connects to the peer.
154 * Setting 'probe_interval' to 0 disables this behavior.
156 * 'max_backoff' is the maximum number of seconds between attempts to connect
157 * to the peer. The actual interval starts at 1 second and doubles on each
158 * failure until it reaches 'max_backoff'. If 0 is specified, the default of
161 * The new rconn is initially unconnected. Use rconn_connect() or
162 * rconn_connect_unreliably() to connect it. */
164 rconn_create(int probe_interval, int max_backoff, uint8_t dscp)
166 struct rconn *rc = xzalloc(sizeof *rc);
169 rc->state_entered = time_now();
172 rc->name = xstrdup("void");
173 rc->target = xstrdup("void");
174 rc->reliable = false;
179 rc->max_backoff = max_backoff ? max_backoff : 8;
180 rc->backoff_deadline = TIME_MIN;
181 rc->last_received = time_now();
182 rc->last_connected = TIME_MIN;
183 rc->last_disconnected = TIME_MIN;
186 rc->packets_sent = 0;
188 rc->probably_admitted = false;
189 rc->last_admitted = time_now();
191 rc->packets_received = 0;
192 rc->n_attempted_connections = 0;
193 rc->n_successful_connections = 0;
194 rc->creation_time = time_now();
195 rc->total_time_connected = 0;
197 rconn_set_probe_interval(rc, probe_interval);
198 rconn_set_dscp(rc, dscp);
206 rconn_set_max_backoff(struct rconn *rc, int max_backoff)
208 rc->max_backoff = MAX(1, max_backoff);
209 if (rc->state == S_BACKOFF && rc->backoff > max_backoff) {
210 rc->backoff = max_backoff;
211 if (rc->backoff_deadline > time_now() + max_backoff) {
212 rc->backoff_deadline = time_now() + max_backoff;
218 rconn_get_max_backoff(const struct rconn *rc)
220 return rc->max_backoff;
224 rconn_set_dscp(struct rconn *rc, uint8_t dscp)
230 rconn_set_probe_interval(struct rconn *rc, int probe_interval)
232 rc->probe_interval = probe_interval ? MAX(5, probe_interval) : 0;
236 rconn_get_probe_interval(const struct rconn *rc)
238 return rc->probe_interval;
241 /* Drops any existing connection on 'rc', then sets up 'rc' to connect to
242 * 'target' and reconnect as needed. 'target' should be a remote OpenFlow
243 * target in a form acceptable to vconn_open().
245 * If 'name' is nonnull, then it is used in log messages in place of 'target'.
246 * It should presumably give more information to a human reader than 'target',
247 * but it need not be acceptable to vconn_open(). */
249 rconn_connect(struct rconn *rc, const char *target, const char *name)
251 rconn_disconnect(rc);
252 rconn_set_target__(rc, target, name);
257 /* Drops any existing connection on 'rc', then configures 'rc' to use
258 * 'vconn'. If the connection on 'vconn' drops, 'rc' will not reconnect on it
261 * By default, the target obtained from vconn_get_name(vconn) is used in log
262 * messages. If 'name' is nonnull, then it is used instead. It should
263 * presumably give more information to a human reader than the target, but it
264 * need not be acceptable to vconn_open(). */
266 rconn_connect_unreliably(struct rconn *rc,
267 struct vconn *vconn, const char *name)
269 assert(vconn != NULL);
270 rconn_disconnect(rc);
271 rconn_set_target__(rc, vconn_get_name(vconn), name);
272 rc->reliable = false;
274 rc->last_connected = time_now();
275 state_transition(rc, S_ACTIVE);
278 /* If 'rc' is connected, forces it to drop the connection and reconnect. */
280 rconn_reconnect(struct rconn *rc)
282 if (rc->state & (S_ACTIVE | S_IDLE)) {
283 VLOG_INFO("%s: disconnecting", rc->name);
289 rconn_disconnect(struct rconn *rc)
291 if (rc->state != S_VOID) {
293 vconn_close(rc->vconn);
296 rconn_set_target__(rc, "void", NULL);
297 rc->reliable = false;
300 rc->backoff_deadline = TIME_MIN;
302 state_transition(rc, S_VOID);
306 /* Disconnects 'rc' and frees the underlying storage. */
308 rconn_destroy(struct rconn *rc)
315 vconn_close(rc->vconn);
317 ofpbuf_list_delete(&rc->txq);
318 for (i = 0; i < rc->n_monitors; i++) {
319 vconn_close(rc->monitors[i]);
326 timeout_VOID(const struct rconn *rc OVS_UNUSED)
332 run_VOID(struct rconn *rc OVS_UNUSED)
338 reconnect(struct rconn *rc)
342 if (rconn_logging_connection_attempts__(rc)) {
343 VLOG_INFO("%s: connecting...", rc->name);
345 rc->n_attempted_connections++;
346 retval = vconn_open(rc->target, OFP10_VERSION, &rc->vconn, rc->dscp);
348 rc->remote_ip = vconn_get_remote_ip(rc->vconn);
349 rc->local_ip = vconn_get_local_ip(rc->vconn);
350 rc->remote_port = vconn_get_remote_port(rc->vconn);
351 rc->backoff_deadline = time_now() + rc->backoff;
352 state_transition(rc, S_CONNECTING);
354 VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(retval));
355 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
356 disconnect(rc, retval);
361 timeout_BACKOFF(const struct rconn *rc)
367 run_BACKOFF(struct rconn *rc)
375 timeout_CONNECTING(const struct rconn *rc)
377 return MAX(1, rc->backoff);
381 run_CONNECTING(struct rconn *rc)
383 int retval = vconn_connect(rc->vconn);
385 VLOG_INFO("%s: connected", rc->name);
386 rc->n_successful_connections++;
387 state_transition(rc, S_ACTIVE);
388 rc->last_connected = rc->state_entered;
389 } else if (retval != EAGAIN) {
390 if (rconn_logging_connection_attempts__(rc)) {
391 VLOG_INFO("%s: connection failed (%s)",
392 rc->name, strerror(retval));
394 disconnect(rc, retval);
395 } else if (timed_out(rc)) {
396 if (rconn_logging_connection_attempts__(rc)) {
397 VLOG_INFO("%s: connection timed out", rc->name);
399 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
400 disconnect(rc, ETIMEDOUT);
405 do_tx_work(struct rconn *rc)
407 if (list_is_empty(&rc->txq)) {
410 while (!list_is_empty(&rc->txq)) {
411 int error = try_send(rc);
416 if (list_is_empty(&rc->txq)) {
417 poll_immediate_wake();
422 timeout_ACTIVE(const struct rconn *rc)
424 if (rc->probe_interval) {
425 unsigned int base = MAX(rc->last_received, rc->state_entered);
426 unsigned int arg = base + rc->probe_interval - rc->state_entered;
433 run_ACTIVE(struct rconn *rc)
436 unsigned int base = MAX(rc->last_received, rc->state_entered);
437 VLOG_DBG("%s: idle %u seconds, sending inactivity probe",
438 rc->name, (unsigned int) (time_now() - base));
440 /* Ordering is important here: rconn_send() can transition to BACKOFF,
441 * and we don't want to transition back to IDLE if so, because then we
442 * can end up queuing a packet with vconn == NULL and then *boom*. */
443 state_transition(rc, S_IDLE);
444 rconn_send(rc, make_echo_request(), NULL);
452 timeout_IDLE(const struct rconn *rc)
454 return rc->probe_interval;
458 run_IDLE(struct rconn *rc)
461 VLOG_ERR("%s: no response to inactivity probe after %u "
462 "seconds, disconnecting",
463 rc->name, elapsed_in_this_state(rc));
464 disconnect(rc, ETIMEDOUT);
470 /* Performs whatever activities are necessary to maintain 'rc': if 'rc' is
471 * disconnected, attempts to (re)connect, backing off as necessary; if 'rc' is
472 * connected, attempts to send packets in the send queue, if any. */
474 rconn_run(struct rconn *rc)
480 vconn_run(rc->vconn);
482 for (i = 0; i < rc->n_monitors; i++) {
483 vconn_run(rc->monitors[i]);
487 old_state = rc->state;
489 #define STATE(NAME, VALUE) case S_##NAME: run_##NAME(rc); break;
495 } while (rc->state != old_state);
498 /* Causes the next call to poll_block() to wake up when rconn_run() should be
501 rconn_run_wait(struct rconn *rc)
507 vconn_run_wait(rc->vconn);
508 if ((rc->state & (S_ACTIVE | S_IDLE)) && !list_is_empty(&rc->txq)) {
509 vconn_wait(rc->vconn, WAIT_SEND);
512 for (i = 0; i < rc->n_monitors; i++) {
513 vconn_run_wait(rc->monitors[i]);
517 if (timeo != UINT_MAX) {
518 long long int expires = sat_add(rc->state_entered, timeo);
519 poll_timer_wait_until(expires * 1000);
523 /* Attempts to receive a packet from 'rc'. If successful, returns the packet;
524 * otherwise, returns a null pointer. The caller is responsible for freeing
525 * the packet (with ofpbuf_delete()). */
527 rconn_recv(struct rconn *rc)
529 if (rc->state & (S_ACTIVE | S_IDLE)) {
530 struct ofpbuf *buffer;
531 int error = vconn_recv(rc->vconn, &buffer);
533 copy_to_monitor(rc, buffer);
534 if (rc->probably_admitted || is_admitted_msg(buffer)
535 || time_now() - rc->last_connected >= 30) {
536 rc->probably_admitted = true;
537 rc->last_admitted = time_now();
539 rc->last_received = time_now();
540 rc->packets_received++;
541 if (rc->state == S_IDLE) {
542 state_transition(rc, S_ACTIVE);
545 } else if (error != EAGAIN) {
546 report_error(rc, error);
547 disconnect(rc, error);
553 /* Causes the next call to poll_block() to wake up when a packet may be ready
554 * to be received by vconn_recv() on 'rc'. */
556 rconn_recv_wait(struct rconn *rc)
559 vconn_wait(rc->vconn, WAIT_RECV);
563 /* Sends 'b' on 'rc'. Returns 0 if successful (in which case 'b' is
564 * destroyed), or ENOTCONN if 'rc' is not currently connected (in which case
565 * the caller retains ownership of 'b').
567 * If 'counter' is non-null, then 'counter' will be incremented while the
568 * packet is in flight, then decremented when it has been sent (or discarded
569 * due to disconnection). Because 'b' may be sent (or discarded) before this
570 * function returns, the caller may not be able to observe any change in
573 * There is no rconn_send_wait() function: an rconn has a send queue that it
574 * takes care of sending if you call rconn_run(), which will have the side
575 * effect of waking up poll_block(). */
577 rconn_send(struct rconn *rc, struct ofpbuf *b,
578 struct rconn_packet_counter *counter)
580 if (rconn_is_connected(rc)) {
581 COVERAGE_INC(rconn_queued);
582 copy_to_monitor(rc, b);
583 b->private_p = counter;
585 rconn_packet_counter_inc(counter);
587 list_push_back(&rc->txq, &b->list_node);
589 /* If the queue was empty before we added 'b', try to send some
590 * packets. (But if the queue had packets in it, it's because the
591 * vconn is backlogged and there's no point in stuffing more into it
592 * now. We'll get back to that in rconn_run().) */
593 if (rc->txq.next == &b->list_node) {
602 /* Sends 'b' on 'rc'. Increments 'counter' while the packet is in flight; it
603 * will be decremented when it has been sent (or discarded due to
604 * disconnection). Returns 0 if successful, EAGAIN if 'counter->n' is already
605 * at least as large as 'queue_limit', or ENOTCONN if 'rc' is not currently
606 * connected. Regardless of return value, 'b' is destroyed.
608 * Because 'b' may be sent (or discarded) before this function returns, the
609 * caller may not be able to observe any change in 'counter'.
611 * There is no rconn_send_wait() function: an rconn has a send queue that it
612 * takes care of sending if you call rconn_run(), which will have the side
613 * effect of waking up poll_block(). */
615 rconn_send_with_limit(struct rconn *rc, struct ofpbuf *b,
616 struct rconn_packet_counter *counter, int queue_limit)
619 retval = counter->n >= queue_limit ? EAGAIN : rconn_send(rc, b, counter);
621 COVERAGE_INC(rconn_overflow);
627 /* Returns the total number of packets successfully sent on the underlying
628 * vconn. A packet is not counted as sent while it is still queued in the
629 * rconn, only when it has been successfuly passed to the vconn. */
631 rconn_packets_sent(const struct rconn *rc)
633 return rc->packets_sent;
636 /* Adds 'vconn' to 'rc' as a monitoring connection, to which all messages sent
637 * and received on 'rconn' will be copied. 'rc' takes ownership of 'vconn'. */
639 rconn_add_monitor(struct rconn *rc, struct vconn *vconn)
641 if (rc->n_monitors < ARRAY_SIZE(rc->monitors)) {
642 VLOG_INFO("new monitor connection from %s", vconn_get_name(vconn));
643 rc->monitors[rc->n_monitors++] = vconn;
645 VLOG_DBG("too many monitor connections, discarding %s",
646 vconn_get_name(vconn));
651 /* Returns 'rc''s name. This is a name for human consumption, appropriate for
652 * use in log messages. It is not necessarily a name that may be passed
653 * directly to, e.g., vconn_open(). */
655 rconn_get_name(const struct rconn *rc)
660 /* Sets 'rc''s name to 'new_name'. */
662 rconn_set_name(struct rconn *rc, const char *new_name)
665 rc->name = xstrdup(new_name);
668 /* Returns 'rc''s target. This is intended to be a string that may be passed
669 * directly to, e.g., vconn_open(). */
671 rconn_get_target(const struct rconn *rc)
676 /* Returns true if 'rconn' is connected or in the process of reconnecting,
677 * false if 'rconn' is disconnected and will not reconnect on its own. */
679 rconn_is_alive(const struct rconn *rconn)
681 return rconn->state != S_VOID;
684 /* Returns true if 'rconn' is connected, false otherwise. */
686 rconn_is_connected(const struct rconn *rconn)
688 return is_connected_state(rconn->state);
691 /* Returns true if 'rconn' is connected and thought to have been accepted by
692 * the peer's admission-control policy. */
694 rconn_is_admitted(const struct rconn *rconn)
696 return (rconn_is_connected(rconn)
697 && rconn->last_admitted >= rconn->last_connected);
700 /* Returns 0 if 'rconn' is currently connected and considered to have been
701 * accepted by the peer's admission-control policy, otherwise the number of
702 * seconds since 'rconn' was last in such a state. */
704 rconn_failure_duration(const struct rconn *rconn)
706 return rconn_is_admitted(rconn) ? 0 : time_now() - rconn->last_admitted;
709 /* Returns the IP address of the peer, or 0 if the peer's IP address is not
712 rconn_get_remote_ip(const struct rconn *rconn)
714 return rconn->remote_ip;
717 /* Returns the transport port of the peer, or 0 if the peer's port is not
720 rconn_get_remote_port(const struct rconn *rconn)
722 return rconn->remote_port;
725 /* Returns the IP address used to connect to the peer, or 0 if the
726 * connection is not an IP-based protocol or if its IP address is not
729 rconn_get_local_ip(const struct rconn *rconn)
731 return rconn->local_ip;
734 /* Returns the transport port used to connect to the peer, or 0 if the
735 * connection does not contain a port or if the port is not known. */
737 rconn_get_local_port(const struct rconn *rconn)
739 return rconn->vconn ? vconn_get_local_port(rconn->vconn) : 0;
742 /* Returns the OpenFlow version negotiated with the peer, or -1 if there is
743 * currently no connection or if version negotiation is not yet complete. */
745 rconn_get_version(const struct rconn *rconn)
747 return rconn->vconn ? vconn_get_version(rconn->vconn) : -1;
750 /* Returns the total number of packets successfully received by the underlying
753 rconn_packets_received(const struct rconn *rc)
755 return rc->packets_received;
758 /* Returns a string representing the internal state of 'rc'. The caller must
759 * not modify or free the string. */
761 rconn_get_state(const struct rconn *rc)
763 return state_name(rc->state);
766 /* Returns the number of connection attempts made by 'rc', including any
767 * ongoing attempt that has not yet succeeded or failed. */
769 rconn_get_attempted_connections(const struct rconn *rc)
771 return rc->n_attempted_connections;
774 /* Returns the number of successful connection attempts made by 'rc'. */
776 rconn_get_successful_connections(const struct rconn *rc)
778 return rc->n_successful_connections;
781 /* Returns the time at which the last successful connection was made by
782 * 'rc'. Returns TIME_MIN if never connected. */
784 rconn_get_last_connection(const struct rconn *rc)
786 return rc->last_connected;
789 /* Returns the time at which 'rc' was last disconnected. Returns TIME_MIN
790 * if never disconnected. */
792 rconn_get_last_disconnect(const struct rconn *rc)
794 return rc->last_disconnected;
797 /* Returns the time at which the last OpenFlow message was received by 'rc'.
798 * If no packets have been received on 'rc', returns the time at which 'rc'
801 rconn_get_last_received(const struct rconn *rc)
803 return rc->last_received;
806 /* Returns the time at which 'rc' was created. */
808 rconn_get_creation_time(const struct rconn *rc)
810 return rc->creation_time;
813 /* Returns the approximate number of seconds that 'rc' has been connected. */
815 rconn_get_total_time_connected(const struct rconn *rc)
817 return (rc->total_time_connected
818 + (rconn_is_connected(rc) ? elapsed_in_this_state(rc) : 0));
821 /* Returns the current amount of backoff, in seconds. This is the amount of
822 * time after which the rconn will transition from BACKOFF to CONNECTING. */
824 rconn_get_backoff(const struct rconn *rc)
829 /* Returns the number of seconds spent in this state so far. */
831 rconn_get_state_elapsed(const struct rconn *rc)
833 return elapsed_in_this_state(rc);
836 /* Returns 'rc''s current connection sequence number, a number that changes
837 * every time that 'rconn' connects or disconnects. */
839 rconn_get_connection_seqno(const struct rconn *rc)
844 /* Returns a value that explains why 'rc' last disconnected:
846 * - 0 means that the last disconnection was caused by a call to
847 * rconn_disconnect(), or that 'rc' is new and has not yet completed its
848 * initial connection or connection attempt.
850 * - EOF means that the connection was closed in the normal way by the peer.
852 * - A positive integer is an errno value that represents the error.
855 rconn_get_last_error(const struct rconn *rc)
857 return rc->last_error;
860 struct rconn_packet_counter *
861 rconn_packet_counter_create(void)
863 struct rconn_packet_counter *c = xmalloc(sizeof *c);
870 rconn_packet_counter_destroy(struct rconn_packet_counter *c)
873 assert(c->ref_cnt > 0);
874 if (!--c->ref_cnt && !c->n) {
881 rconn_packet_counter_inc(struct rconn_packet_counter *c)
887 rconn_packet_counter_dec(struct rconn_packet_counter *c)
890 if (!--c->n && !c->ref_cnt) {
895 /* Set rc->target and rc->name to 'target' and 'name', respectively. If 'name'
896 * is null, 'target' is used.
898 * Also, clear out the cached IP address and port information, since changing
899 * the target also likely changes these values. */
901 rconn_set_target__(struct rconn *rc, const char *target, const char *name)
904 rc->name = xstrdup(name ? name : target);
906 rc->target = xstrdup(target);
912 /* Tries to send a packet from 'rc''s send buffer. Returns 0 if successful,
913 * otherwise a positive errno value. */
915 try_send(struct rconn *rc)
917 struct ofpbuf *msg = ofpbuf_from_list(rc->txq.next);
918 struct rconn_packet_counter *counter = msg->private_p;
921 /* Eagerly remove 'msg' from the txq. We can't remove it from the list
922 * after sending, if sending is successful, because it is then owned by the
923 * vconn, which might have freed it already. */
924 list_remove(&msg->list_node);
926 retval = vconn_send(rc->vconn, msg);
928 list_push_front(&rc->txq, &msg->list_node);
929 if (retval != EAGAIN) {
930 report_error(rc, retval);
931 disconnect(rc, retval);
935 COVERAGE_INC(rconn_sent);
938 rconn_packet_counter_dec(counter);
943 /* Reports that 'error' caused 'rc' to disconnect. 'error' may be a positive
944 * errno value, or it may be EOF to indicate that the connection was closed
947 report_error(struct rconn *rc, int error)
950 /* If 'rc' isn't reliable, then we don't really expect this connection
951 * to last forever anyway (probably it's a connection that we received
952 * via accept()), so use DBG level to avoid cluttering the logs. */
953 enum vlog_level level = rc->reliable ? VLL_INFO : VLL_DBG;
954 VLOG(level, "%s: connection closed by peer", rc->name);
956 VLOG_WARN("%s: connection dropped (%s)", rc->name, strerror(error));
960 /* Disconnects 'rc' and records 'error' as the error that caused 'rc''s last
963 * - 0 means that this disconnection is due to a request by 'rc''s client,
964 * not due to any kind of network error.
966 * - EOF means that the connection was closed in the normal way by the peer.
968 * - A positive integer is an errno value that represents the error.
971 disconnect(struct rconn *rc, int error)
973 rc->last_error = error;
975 time_t now = time_now();
977 if (rc->state & (S_CONNECTING | S_ACTIVE | S_IDLE)) {
978 rc->last_disconnected = now;
979 vconn_close(rc->vconn);
984 if (now >= rc->backoff_deadline) {
986 } else if (rc->backoff < rc->max_backoff / 2) {
987 rc->backoff = MAX(1, 2 * rc->backoff);
988 VLOG_INFO("%s: waiting %d seconds before reconnect",
989 rc->name, rc->backoff);
991 if (rconn_logging_connection_attempts__(rc)) {
992 VLOG_INFO("%s: continuing to retry connections in the "
993 "background but suppressing further logging",
996 rc->backoff = rc->max_backoff;
998 rc->backoff_deadline = now + rc->backoff;
999 state_transition(rc, S_BACKOFF);
1001 rc->last_disconnected = time_now();
1002 rconn_disconnect(rc);
1006 /* Drops all the packets from 'rc''s send queue and decrements their queue
1009 flush_queue(struct rconn *rc)
1011 if (list_is_empty(&rc->txq)) {
1014 while (!list_is_empty(&rc->txq)) {
1015 struct ofpbuf *b = ofpbuf_from_list(list_pop_front(&rc->txq));
1016 struct rconn_packet_counter *counter = b->private_p;
1018 rconn_packet_counter_dec(counter);
1020 COVERAGE_INC(rconn_discarded);
1023 poll_immediate_wake();
1027 elapsed_in_this_state(const struct rconn *rc)
1029 return time_now() - rc->state_entered;
1033 timeout(const struct rconn *rc)
1035 switch (rc->state) {
1036 #define STATE(NAME, VALUE) case S_##NAME: return timeout_##NAME(rc);
1045 timed_out(const struct rconn *rc)
1047 return time_now() >= sat_add(rc->state_entered, timeout(rc));
1051 state_transition(struct rconn *rc, enum state state)
1053 rc->seqno += (rc->state == S_ACTIVE) != (state == S_ACTIVE);
1054 if (is_connected_state(state) && !is_connected_state(rc->state)) {
1055 rc->probably_admitted = false;
1057 if (rconn_is_connected(rc)) {
1058 rc->total_time_connected += elapsed_in_this_state(rc);
1060 VLOG_DBG("%s: entering %s", rc->name, state_name(state));
1062 rc->state_entered = time_now();
1066 copy_to_monitor(struct rconn *rc, const struct ofpbuf *b)
1068 struct ofpbuf *clone = NULL;
1072 for (i = 0; i < rc->n_monitors; ) {
1073 struct vconn *vconn = rc->monitors[i];
1076 clone = ofpbuf_clone(b);
1078 retval = vconn_send(vconn, clone);
1081 } else if (retval != EAGAIN) {
1082 VLOG_DBG("%s: closing monitor connection to %s: %s",
1083 rconn_get_name(rc), vconn_get_name(vconn),
1085 rc->monitors[i] = rc->monitors[--rc->n_monitors];
1090 ofpbuf_delete(clone);
1094 is_connected_state(enum state state)
1096 return (state & (S_ACTIVE | S_IDLE)) != 0;
1100 is_admitted_msg(const struct ofpbuf *b)
1102 struct ofp_header *oh = b->data;
1103 uint8_t type = oh->type;
1105 && (1u << type) & ((1u << OFPT_HELLO) |
1106 (1u << OFPT_ERROR) |
1107 (1u << OFPT_ECHO_REQUEST) |
1108 (1u << OFPT_ECHO_REPLY) |
1109 (1u << OFPT_VENDOR) |
1110 (1u << OFPT_FEATURES_REQUEST) |
1111 (1u << OFPT_FEATURES_REPLY) |
1112 (1u << OFPT_GET_CONFIG_REQUEST) |
1113 (1u << OFPT_GET_CONFIG_REPLY) |
1114 (1u << OFPT_SET_CONFIG)));
1117 /* Returns true if 'rc' is currently logging information about connection
1118 * attempts, false if logging should be suppressed because 'rc' hasn't
1119 * successuflly connected in too long. */
1121 rconn_logging_connection_attempts__(const struct rconn *rc)
1123 return rc->backoff < rc->max_backoff;