2 * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
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, or ENOTCONN if 'rc' is not
564 * currently connected. Takes ownership of 'b'.
566 * If 'counter' is non-null, then 'counter' will be incremented while the
567 * packet is in flight, then decremented when it has been sent (or discarded
568 * due to disconnection). Because 'b' may be sent (or discarded) before this
569 * function returns, the caller may not be able to observe any change in
572 * There is no rconn_send_wait() function: an rconn has a send queue that it
573 * takes care of sending if you call rconn_run(), which will have the side
574 * effect of waking up poll_block(). */
576 rconn_send(struct rconn *rc, struct ofpbuf *b,
577 struct rconn_packet_counter *counter)
579 if (rconn_is_connected(rc)) {
580 COVERAGE_INC(rconn_queued);
581 copy_to_monitor(rc, b);
582 b->private_p = counter;
584 rconn_packet_counter_inc(counter);
586 list_push_back(&rc->txq, &b->list_node);
588 /* If the queue was empty before we added 'b', try to send some
589 * packets. (But if the queue had packets in it, it's because the
590 * vconn is backlogged and there's no point in stuffing more into it
591 * now. We'll get back to that in rconn_run().) */
592 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);
626 /* Returns the total number of packets successfully sent on the underlying
627 * vconn. A packet is not counted as sent while it is still queued in the
628 * rconn, only when it has been successfuly passed to the vconn. */
630 rconn_packets_sent(const struct rconn *rc)
632 return rc->packets_sent;
635 /* Adds 'vconn' to 'rc' as a monitoring connection, to which all messages sent
636 * and received on 'rconn' will be copied. 'rc' takes ownership of 'vconn'. */
638 rconn_add_monitor(struct rconn *rc, struct vconn *vconn)
640 if (rc->n_monitors < ARRAY_SIZE(rc->monitors)) {
641 VLOG_INFO("new monitor connection from %s", vconn_get_name(vconn));
642 rc->monitors[rc->n_monitors++] = vconn;
644 VLOG_DBG("too many monitor connections, discarding %s",
645 vconn_get_name(vconn));
650 /* Returns 'rc''s name. This is a name for human consumption, appropriate for
651 * use in log messages. It is not necessarily a name that may be passed
652 * directly to, e.g., vconn_open(). */
654 rconn_get_name(const struct rconn *rc)
659 /* Sets 'rc''s name to 'new_name'. */
661 rconn_set_name(struct rconn *rc, const char *new_name)
664 rc->name = xstrdup(new_name);
667 /* Returns 'rc''s target. This is intended to be a string that may be passed
668 * directly to, e.g., vconn_open(). */
670 rconn_get_target(const struct rconn *rc)
675 /* Returns true if 'rconn' is connected or in the process of reconnecting,
676 * false if 'rconn' is disconnected and will not reconnect on its own. */
678 rconn_is_alive(const struct rconn *rconn)
680 return rconn->state != S_VOID;
683 /* Returns true if 'rconn' is connected, false otherwise. */
685 rconn_is_connected(const struct rconn *rconn)
687 return is_connected_state(rconn->state);
690 /* Returns true if 'rconn' is connected and thought to have been accepted by
691 * the peer's admission-control policy. */
693 rconn_is_admitted(const struct rconn *rconn)
695 return (rconn_is_connected(rconn)
696 && rconn->last_admitted >= rconn->last_connected);
699 /* Returns 0 if 'rconn' is currently connected and considered to have been
700 * accepted by the peer's admission-control policy, otherwise the number of
701 * seconds since 'rconn' was last in such a state. */
703 rconn_failure_duration(const struct rconn *rconn)
705 return rconn_is_admitted(rconn) ? 0 : time_now() - rconn->last_admitted;
708 /* Returns the IP address of the peer, or 0 if the peer's IP address is not
711 rconn_get_remote_ip(const struct rconn *rconn)
713 return rconn->remote_ip;
716 /* Returns the transport port of the peer, or 0 if the peer's port is not
719 rconn_get_remote_port(const struct rconn *rconn)
721 return rconn->remote_port;
724 /* Returns the IP address used to connect to the peer, or 0 if the
725 * connection is not an IP-based protocol or if its IP address is not
728 rconn_get_local_ip(const struct rconn *rconn)
730 return rconn->local_ip;
733 /* Returns the transport port used to connect to the peer, or 0 if the
734 * connection does not contain a port or if the port is not known. */
736 rconn_get_local_port(const struct rconn *rconn)
738 return rconn->vconn ? vconn_get_local_port(rconn->vconn) : 0;
741 /* Returns the OpenFlow version negotiated with the peer, or -1 if there is
742 * currently no connection or if version negotiation is not yet complete. */
744 rconn_get_version(const struct rconn *rconn)
746 return rconn->vconn ? vconn_get_version(rconn->vconn) : -1;
749 /* Returns the total number of packets successfully received by the underlying
752 rconn_packets_received(const struct rconn *rc)
754 return rc->packets_received;
757 /* Returns a string representing the internal state of 'rc'. The caller must
758 * not modify or free the string. */
760 rconn_get_state(const struct rconn *rc)
762 return state_name(rc->state);
765 /* Returns the number of connection attempts made by 'rc', including any
766 * ongoing attempt that has not yet succeeded or failed. */
768 rconn_get_attempted_connections(const struct rconn *rc)
770 return rc->n_attempted_connections;
773 /* Returns the number of successful connection attempts made by 'rc'. */
775 rconn_get_successful_connections(const struct rconn *rc)
777 return rc->n_successful_connections;
780 /* Returns the time at which the last successful connection was made by
781 * 'rc'. Returns TIME_MIN if never connected. */
783 rconn_get_last_connection(const struct rconn *rc)
785 return rc->last_connected;
788 /* Returns the time at which 'rc' was last disconnected. Returns TIME_MIN
789 * if never disconnected. */
791 rconn_get_last_disconnect(const struct rconn *rc)
793 return rc->last_disconnected;
796 /* Returns the time at which the last OpenFlow message was received by 'rc'.
797 * If no packets have been received on 'rc', returns the time at which 'rc'
800 rconn_get_last_received(const struct rconn *rc)
802 return rc->last_received;
805 /* Returns the time at which 'rc' was created. */
807 rconn_get_creation_time(const struct rconn *rc)
809 return rc->creation_time;
812 /* Returns the approximate number of seconds that 'rc' has been connected. */
814 rconn_get_total_time_connected(const struct rconn *rc)
816 return (rc->total_time_connected
817 + (rconn_is_connected(rc) ? elapsed_in_this_state(rc) : 0));
820 /* Returns the current amount of backoff, in seconds. This is the amount of
821 * time after which the rconn will transition from BACKOFF to CONNECTING. */
823 rconn_get_backoff(const struct rconn *rc)
828 /* Returns the number of seconds spent in this state so far. */
830 rconn_get_state_elapsed(const struct rconn *rc)
832 return elapsed_in_this_state(rc);
835 /* Returns 'rc''s current connection sequence number, a number that changes
836 * every time that 'rconn' connects or disconnects. */
838 rconn_get_connection_seqno(const struct rconn *rc)
843 /* Returns a value that explains why 'rc' last disconnected:
845 * - 0 means that the last disconnection was caused by a call to
846 * rconn_disconnect(), or that 'rc' is new and has not yet completed its
847 * initial connection or connection attempt.
849 * - EOF means that the connection was closed in the normal way by the peer.
851 * - A positive integer is an errno value that represents the error.
854 rconn_get_last_error(const struct rconn *rc)
856 return rc->last_error;
859 /* Returns the number of messages queued for transmission on 'rc'. */
861 rconn_count_txqlen(const struct rconn *rc)
863 return list_size(&rc->txq);
866 struct rconn_packet_counter *
867 rconn_packet_counter_create(void)
869 struct rconn_packet_counter *c = xmalloc(sizeof *c);
876 rconn_packet_counter_destroy(struct rconn_packet_counter *c)
879 assert(c->ref_cnt > 0);
880 if (!--c->ref_cnt && !c->n) {
887 rconn_packet_counter_inc(struct rconn_packet_counter *c)
893 rconn_packet_counter_dec(struct rconn_packet_counter *c)
896 if (!--c->n && !c->ref_cnt) {
901 /* Set rc->target and rc->name to 'target' and 'name', respectively. If 'name'
902 * is null, 'target' is used.
904 * Also, clear out the cached IP address and port information, since changing
905 * the target also likely changes these values. */
907 rconn_set_target__(struct rconn *rc, const char *target, const char *name)
910 rc->name = xstrdup(name ? name : target);
912 rc->target = xstrdup(target);
918 /* Tries to send a packet from 'rc''s send buffer. Returns 0 if successful,
919 * otherwise a positive errno value. */
921 try_send(struct rconn *rc)
923 struct ofpbuf *msg = ofpbuf_from_list(rc->txq.next);
924 struct rconn_packet_counter *counter = msg->private_p;
927 /* Eagerly remove 'msg' from the txq. We can't remove it from the list
928 * after sending, if sending is successful, because it is then owned by the
929 * vconn, which might have freed it already. */
930 list_remove(&msg->list_node);
932 retval = vconn_send(rc->vconn, msg);
934 list_push_front(&rc->txq, &msg->list_node);
935 if (retval != EAGAIN) {
936 report_error(rc, retval);
937 disconnect(rc, retval);
941 COVERAGE_INC(rconn_sent);
944 rconn_packet_counter_dec(counter);
949 /* Reports that 'error' caused 'rc' to disconnect. 'error' may be a positive
950 * errno value, or it may be EOF to indicate that the connection was closed
953 report_error(struct rconn *rc, int error)
956 /* If 'rc' isn't reliable, then we don't really expect this connection
957 * to last forever anyway (probably it's a connection that we received
958 * via accept()), so use DBG level to avoid cluttering the logs. */
959 enum vlog_level level = rc->reliable ? VLL_INFO : VLL_DBG;
960 VLOG(level, "%s: connection closed by peer", rc->name);
962 VLOG_WARN("%s: connection dropped (%s)", rc->name, strerror(error));
966 /* Disconnects 'rc' and records 'error' as the error that caused 'rc''s last
969 * - 0 means that this disconnection is due to a request by 'rc''s client,
970 * not due to any kind of network error.
972 * - EOF means that the connection was closed in the normal way by the peer.
974 * - A positive integer is an errno value that represents the error.
977 disconnect(struct rconn *rc, int error)
979 rc->last_error = error;
981 time_t now = time_now();
983 if (rc->state & (S_CONNECTING | S_ACTIVE | S_IDLE)) {
984 rc->last_disconnected = now;
985 vconn_close(rc->vconn);
990 if (now >= rc->backoff_deadline) {
992 } else if (rc->backoff < rc->max_backoff / 2) {
993 rc->backoff = MAX(1, 2 * rc->backoff);
994 VLOG_INFO("%s: waiting %d seconds before reconnect",
995 rc->name, rc->backoff);
997 if (rconn_logging_connection_attempts__(rc)) {
998 VLOG_INFO("%s: continuing to retry connections in the "
999 "background but suppressing further logging",
1002 rc->backoff = rc->max_backoff;
1004 rc->backoff_deadline = now + rc->backoff;
1005 state_transition(rc, S_BACKOFF);
1007 rc->last_disconnected = time_now();
1008 rconn_disconnect(rc);
1012 /* Drops all the packets from 'rc''s send queue and decrements their queue
1015 flush_queue(struct rconn *rc)
1017 if (list_is_empty(&rc->txq)) {
1020 while (!list_is_empty(&rc->txq)) {
1021 struct ofpbuf *b = ofpbuf_from_list(list_pop_front(&rc->txq));
1022 struct rconn_packet_counter *counter = b->private_p;
1024 rconn_packet_counter_dec(counter);
1026 COVERAGE_INC(rconn_discarded);
1029 poll_immediate_wake();
1033 elapsed_in_this_state(const struct rconn *rc)
1035 return time_now() - rc->state_entered;
1039 timeout(const struct rconn *rc)
1041 switch (rc->state) {
1042 #define STATE(NAME, VALUE) case S_##NAME: return timeout_##NAME(rc);
1051 timed_out(const struct rconn *rc)
1053 return time_now() >= sat_add(rc->state_entered, timeout(rc));
1057 state_transition(struct rconn *rc, enum state state)
1059 rc->seqno += (rc->state == S_ACTIVE) != (state == S_ACTIVE);
1060 if (is_connected_state(state) && !is_connected_state(rc->state)) {
1061 rc->probably_admitted = false;
1063 if (rconn_is_connected(rc)) {
1064 rc->total_time_connected += elapsed_in_this_state(rc);
1066 VLOG_DBG("%s: entering %s", rc->name, state_name(state));
1068 rc->state_entered = time_now();
1072 copy_to_monitor(struct rconn *rc, const struct ofpbuf *b)
1074 struct ofpbuf *clone = NULL;
1078 for (i = 0; i < rc->n_monitors; ) {
1079 struct vconn *vconn = rc->monitors[i];
1082 clone = ofpbuf_clone(b);
1084 retval = vconn_send(vconn, clone);
1087 } else if (retval != EAGAIN) {
1088 VLOG_DBG("%s: closing monitor connection to %s: %s",
1089 rconn_get_name(rc), vconn_get_name(vconn),
1091 rc->monitors[i] = rc->monitors[--rc->n_monitors];
1096 ofpbuf_delete(clone);
1100 is_connected_state(enum state state)
1102 return (state & (S_ACTIVE | S_IDLE)) != 0;
1106 is_admitted_msg(const struct ofpbuf *b)
1108 struct ofp_header *oh = b->data;
1109 uint8_t type = oh->type;
1111 && (1u << type) & ((1u << OFPT_HELLO) |
1112 (1u << OFPT_ERROR) |
1113 (1u << OFPT_ECHO_REQUEST) |
1114 (1u << OFPT_ECHO_REPLY) |
1115 (1u << OFPT_VENDOR) |
1116 (1u << OFPT_FEATURES_REQUEST) |
1117 (1u << OFPT_FEATURES_REPLY) |
1118 (1u << OFPT_GET_CONFIG_REQUEST) |
1119 (1u << OFPT_GET_CONFIG_REPLY) |
1120 (1u << OFPT_SET_CONFIG)));
1123 /* Returns true if 'rc' is currently logging information about connection
1124 * attempts, false if logging should be suppressed because 'rc' hasn't
1125 * successuflly connected in too long. */
1127 rconn_logging_connection_attempts__(const struct rconn *rc)
1129 return rc->backoff < rc->max_backoff;