2 * Copyright (c) 2008, 2009, 2010 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"
34 #define THIS_MODULE VLM_rconn
39 STATE(BACKOFF, 1 << 1) \
40 STATE(CONNECTING, 1 << 2) \
41 STATE(ACTIVE, 1 << 3) \
44 #define STATE(NAME, VALUE) S_##NAME = VALUE,
50 state_name(enum state state)
53 #define STATE(NAME, VALUE) case S_##NAME: return #NAME;
60 /* A reliable connection to an OpenFlow switch or controller.
62 * See the large comment in rconn.h for more information. */
68 char *name; /* Human-readable descriptive name. */
69 char *target; /* vconn name, passed to vconn_open(). */
76 time_t backoff_deadline;
78 time_t last_connected;
79 unsigned int packets_sent;
83 /* In S_ACTIVE and S_IDLE, probably_admitted reports whether we believe
84 * that the peer has made a (positive) admission control decision on our
85 * connection. If we have not yet been (probably) admitted, then the
86 * connection does not reset the timer used for deciding whether the switch
87 * should go into fail-open mode.
89 * last_admitted reports the last time we believe such a positive admission
90 * control decision was made. */
91 bool probably_admitted;
94 /* These values are simply for statistics reporting, not used directly by
95 * anything internal to the rconn (or ofproto for that matter). */
96 unsigned int packets_received;
97 unsigned int n_attempted_connections, n_successful_connections;
99 unsigned long int total_time_connected;
101 /* If we can't connect to the peer, it could be for any number of reasons.
102 * Usually, one would assume it is because the peer is not running or
103 * because the network is partitioned. But it could also be because the
104 * network topology has changed, in which case the upper layer will need to
105 * reassess it (in particular, obtain a new IP address via DHCP and find
106 * the new location of the controller). We set this flag when we suspect
107 * that this could be the case. */
108 bool questionable_connectivity;
109 time_t last_questioned;
111 /* Throughout this file, "probe" is shorthand for "inactivity probe".
112 * When nothing has been received from the peer for a while, we send out
113 * an echo request as an inactivity probe packet. We should receive back
115 int probe_interval; /* Secs of inactivity before sending probe. */
117 /* When we create a vconn we obtain these values, to save them past the end
118 * of the vconn's lifetime. Otherwise, in-band control will only allow
119 * traffic when a vconn is actually open, but it is nice to allow ARP to
120 * complete even between connection attempts, and it is also polite to
121 * allow traffic from other switches to go through to the controller
122 * whether or not we are connected.
124 * We don't cache the local port, because that changes from one connection
125 * attempt to the next. */
126 uint32_t local_ip, remote_ip;
127 uint16_t remote_port;
129 /* Messages sent or received are copied to the monitor connections. */
130 #define MAX_MONITORS 8
131 struct vconn *monitors[8];
135 static unsigned int elapsed_in_this_state(const struct rconn *);
136 static unsigned int timeout(const struct rconn *);
137 static bool timed_out(const struct rconn *);
138 static void state_transition(struct rconn *, enum state);
139 static void rconn_set_target__(struct rconn *,
140 const char *target, const char *name);
141 static int try_send(struct rconn *);
142 static void reconnect(struct rconn *);
143 static void report_error(struct rconn *, int error);
144 static void disconnect(struct rconn *, int error);
145 static void flush_queue(struct rconn *);
146 static void question_connectivity(struct rconn *);
147 static void copy_to_monitor(struct rconn *, const struct ofpbuf *);
148 static bool is_connected_state(enum state);
149 static bool is_admitted_msg(const struct ofpbuf *);
151 /* Creates and returns a new rconn.
153 * 'probe_interval' is a number of seconds. If the interval passes once
154 * without an OpenFlow message being received from the peer, the rconn sends
155 * out an "echo request" message. If the interval passes again without a
156 * message being received, the rconn disconnects and re-connects to the peer.
157 * Setting 'probe_interval' to 0 disables this behavior.
159 * 'max_backoff' is the maximum number of seconds between attempts to connect
160 * to the peer. The actual interval starts at 1 second and doubles on each
161 * failure until it reaches 'max_backoff'. If 0 is specified, the default of
164 * The new rconn is initially unconnected. Use rconn_connect() or
165 * rconn_connect_unreliably() to connect it. */
167 rconn_create(int probe_interval, int max_backoff)
169 struct rconn *rc = xzalloc(sizeof *rc);
172 rc->state_entered = time_now();
175 rc->name = xstrdup("void");
176 rc->target = xstrdup("void");
177 rc->reliable = false;
179 queue_init(&rc->txq);
182 rc->max_backoff = max_backoff ? max_backoff : 8;
183 rc->backoff_deadline = TIME_MIN;
184 rc->last_received = time_now();
185 rc->last_connected = time_now();
188 rc->packets_sent = 0;
190 rc->probably_admitted = false;
191 rc->last_admitted = time_now();
193 rc->packets_received = 0;
194 rc->n_attempted_connections = 0;
195 rc->n_successful_connections = 0;
196 rc->creation_time = time_now();
197 rc->total_time_connected = 0;
199 rc->questionable_connectivity = false;
200 rc->last_questioned = time_now();
202 rconn_set_probe_interval(rc, probe_interval);
210 rconn_set_max_backoff(struct rconn *rc, int max_backoff)
212 rc->max_backoff = MAX(1, max_backoff);
213 if (rc->state == S_BACKOFF && rc->backoff > max_backoff) {
214 rc->backoff = max_backoff;
215 if (rc->backoff_deadline > time_now() + max_backoff) {
216 rc->backoff_deadline = time_now() + max_backoff;
222 rconn_get_max_backoff(const struct rconn *rc)
224 return rc->max_backoff;
228 rconn_set_probe_interval(struct rconn *rc, int probe_interval)
230 rc->probe_interval = probe_interval ? MAX(5, probe_interval) : 0;
234 rconn_get_probe_interval(const struct rconn *rc)
236 return rc->probe_interval;
239 /* Drops any existing connection on 'rc', then sets up 'rc' to connect to
240 * 'target' and reconnect as needed. 'target' should be a remote OpenFlow
241 * target in a form acceptable to vconn_open().
243 * If 'name' is nonnull, then it is used in log messages in place of 'target'.
244 * It should presumably give more information to a human reader than 'target',
245 * but it need not be acceptable to vconn_open(). */
247 rconn_connect(struct rconn *rc, const char *target, const char *name)
249 rconn_disconnect(rc);
250 rconn_set_target__(rc, target, name);
255 /* Drops any existing connection on 'rc', then configures 'rc' to use
256 * 'vconn'. If the connection on 'vconn' drops, 'rc' will not reconnect on it
259 * By default, the target obtained from vconn_get_name(vconn) is used in log
260 * messages. If 'name' is nonnull, then it is used instead. It should
261 * presumably give more information to a human reader than the target, but it
262 * need not be acceptable to vconn_open(). */
264 rconn_connect_unreliably(struct rconn *rc,
265 struct vconn *vconn, const char *name)
267 assert(vconn != NULL);
268 rconn_disconnect(rc);
269 rconn_set_target__(rc, vconn_get_name(vconn), name);
270 rc->reliable = false;
272 rc->last_connected = time_now();
273 state_transition(rc, S_ACTIVE);
276 /* If 'rc' is connected, forces it to drop the connection and reconnect. */
278 rconn_reconnect(struct rconn *rc)
280 if (rc->state & (S_ACTIVE | S_IDLE)) {
281 VLOG_INFO("%s: disconnecting", rc->name);
287 rconn_disconnect(struct rconn *rc)
289 if (rc->state != S_VOID) {
291 vconn_close(rc->vconn);
294 rconn_set_target__(rc, "void", NULL);
295 rc->reliable = false;
298 rc->backoff_deadline = TIME_MIN;
300 state_transition(rc, S_VOID);
304 /* Disconnects 'rc' and frees the underlying storage. */
306 rconn_destroy(struct rconn *rc)
313 vconn_close(rc->vconn);
315 queue_destroy(&rc->txq);
316 for (i = 0; i < rc->n_monitors; i++) {
317 vconn_close(rc->monitors[i]);
324 timeout_VOID(const struct rconn *rc OVS_UNUSED)
330 run_VOID(struct rconn *rc OVS_UNUSED)
336 reconnect(struct rconn *rc)
340 VLOG_INFO("%s: connecting...", rc->name);
341 rc->n_attempted_connections++;
342 retval = vconn_open(rc->target, OFP_VERSION, &rc->vconn);
344 rc->remote_ip = vconn_get_remote_ip(rc->vconn);
345 rc->local_ip = vconn_get_local_ip(rc->vconn);
346 rc->remote_port = vconn_get_remote_port(rc->vconn);
347 rc->backoff_deadline = time_now() + rc->backoff;
348 state_transition(rc, S_CONNECTING);
350 VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(retval));
351 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
352 disconnect(rc, retval);
357 timeout_BACKOFF(const struct rconn *rc)
363 run_BACKOFF(struct rconn *rc)
371 timeout_CONNECTING(const struct rconn *rc)
373 return MAX(1, rc->backoff);
377 run_CONNECTING(struct rconn *rc)
379 int retval = vconn_connect(rc->vconn);
381 VLOG_INFO("%s: connected", rc->name);
382 rc->n_successful_connections++;
383 state_transition(rc, S_ACTIVE);
384 rc->last_connected = rc->state_entered;
385 } else if (retval != EAGAIN) {
386 VLOG_INFO("%s: connection failed (%s)", rc->name, strerror(retval));
387 disconnect(rc, retval);
388 } else if (timed_out(rc)) {
389 VLOG_INFO("%s: connection timed out", rc->name);
390 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
391 disconnect(rc, ETIMEDOUT);
396 do_tx_work(struct rconn *rc)
401 while (rc->txq.n > 0) {
402 int error = try_send(rc);
408 poll_immediate_wake();
413 timeout_ACTIVE(const struct rconn *rc)
415 if (rc->probe_interval) {
416 unsigned int base = MAX(rc->last_received, rc->state_entered);
417 unsigned int arg = base + rc->probe_interval - rc->state_entered;
424 run_ACTIVE(struct rconn *rc)
427 unsigned int base = MAX(rc->last_received, rc->state_entered);
428 VLOG_DBG("%s: idle %u seconds, sending inactivity probe",
429 rc->name, (unsigned int) (time_now() - base));
431 /* Ordering is important here: rconn_send() can transition to BACKOFF,
432 * and we don't want to transition back to IDLE if so, because then we
433 * can end up queuing a packet with vconn == NULL and then *boom*. */
434 state_transition(rc, S_IDLE);
435 rconn_send(rc, make_echo_request(), NULL);
443 timeout_IDLE(const struct rconn *rc)
445 return rc->probe_interval;
449 run_IDLE(struct rconn *rc)
452 question_connectivity(rc);
453 VLOG_ERR("%s: no response to inactivity probe after %u "
454 "seconds, disconnecting",
455 rc->name, elapsed_in_this_state(rc));
456 disconnect(rc, ETIMEDOUT);
462 /* Performs whatever activities are necessary to maintain 'rc': if 'rc' is
463 * disconnected, attempts to (re)connect, backing off as necessary; if 'rc' is
464 * connected, attempts to send packets in the send queue, if any. */
466 rconn_run(struct rconn *rc)
472 vconn_run(rc->vconn);
474 for (i = 0; i < rc->n_monitors; i++) {
475 vconn_run(rc->monitors[i]);
479 old_state = rc->state;
481 #define STATE(NAME, VALUE) case S_##NAME: run_##NAME(rc); break;
487 } while (rc->state != old_state);
490 /* Causes the next call to poll_block() to wake up when rconn_run() should be
493 rconn_run_wait(struct rconn *rc)
499 vconn_run_wait(rc->vconn);
501 for (i = 0; i < rc->n_monitors; i++) {
502 vconn_run_wait(rc->monitors[i]);
506 if (timeo != UINT_MAX) {
507 long long int expires = sat_add(rc->state_entered, timeo);
508 poll_timer_wait_until(expires * 1000);
511 if ((rc->state & (S_ACTIVE | S_IDLE)) && rc->txq.n) {
512 vconn_wait(rc->vconn, WAIT_SEND);
516 /* Attempts to receive a packet from 'rc'. If successful, returns the packet;
517 * otherwise, returns a null pointer. The caller is responsible for freeing
518 * the packet (with ofpbuf_delete()). */
520 rconn_recv(struct rconn *rc)
522 if (rc->state & (S_ACTIVE | S_IDLE)) {
523 struct ofpbuf *buffer;
524 int error = vconn_recv(rc->vconn, &buffer);
526 copy_to_monitor(rc, buffer);
527 if (rc->probably_admitted || is_admitted_msg(buffer)
528 || time_now() - rc->last_connected >= 30) {
529 rc->probably_admitted = true;
530 rc->last_admitted = time_now();
532 rc->last_received = time_now();
533 rc->packets_received++;
534 if (rc->state == S_IDLE) {
535 state_transition(rc, S_ACTIVE);
538 } else if (error != EAGAIN) {
539 report_error(rc, error);
540 disconnect(rc, error);
546 /* Causes the next call to poll_block() to wake up when a packet may be ready
547 * to be received by vconn_recv() on 'rc'. */
549 rconn_recv_wait(struct rconn *rc)
552 vconn_wait(rc->vconn, WAIT_RECV);
556 /* Sends 'b' on 'rc'. Returns 0 if successful (in which case 'b' is
557 * destroyed), or ENOTCONN if 'rc' is not currently connected (in which case
558 * the caller retains ownership of 'b').
560 * If 'counter' is non-null, then 'counter' will be incremented while the
561 * packet is in flight, then decremented when it has been sent (or discarded
562 * due to disconnection). Because 'b' may be sent (or discarded) before this
563 * function returns, the caller may not be able to observe any change in
566 * There is no rconn_send_wait() function: an rconn has a send queue that it
567 * takes care of sending if you call rconn_run(), which will have the side
568 * effect of waking up poll_block(). */
570 rconn_send(struct rconn *rc, struct ofpbuf *b,
571 struct rconn_packet_counter *counter)
573 if (rconn_is_connected(rc)) {
574 COVERAGE_INC(rconn_queued);
575 copy_to_monitor(rc, b);
576 b->private_p = counter;
578 rconn_packet_counter_inc(counter);
580 queue_push_tail(&rc->txq, b);
582 /* If the queue was empty before we added 'b', try to send some
583 * packets. (But if the queue had packets in it, it's because the
584 * vconn is backlogged and there's no point in stuffing more into it
585 * now. We'll get back to that in rconn_run().) */
586 if (rc->txq.n == 1) {
595 /* Sends 'b' on 'rc'. Increments 'counter' while the packet is in flight; it
596 * will be decremented when it has been sent (or discarded due to
597 * disconnection). Returns 0 if successful, EAGAIN if 'counter->n' is already
598 * at least as large as 'queue_limit', or ENOTCONN if 'rc' is not currently
599 * connected. Regardless of return value, 'b' is destroyed.
601 * Because 'b' may be sent (or discarded) before this function returns, the
602 * caller may not be able to observe any change in 'counter'.
604 * There is no rconn_send_wait() function: an rconn has a send queue that it
605 * takes care of sending if you call rconn_run(), which will have the side
606 * effect of waking up poll_block(). */
608 rconn_send_with_limit(struct rconn *rc, struct ofpbuf *b,
609 struct rconn_packet_counter *counter, int queue_limit)
612 retval = counter->n >= queue_limit ? EAGAIN : rconn_send(rc, b, counter);
614 COVERAGE_INC(rconn_overflow);
620 /* Returns the total number of packets successfully sent on the underlying
621 * vconn. A packet is not counted as sent while it is still queued in the
622 * rconn, only when it has been successfuly passed to the vconn. */
624 rconn_packets_sent(const struct rconn *rc)
626 return rc->packets_sent;
629 /* Adds 'vconn' to 'rc' as a monitoring connection, to which all messages sent
630 * and received on 'rconn' will be copied. 'rc' takes ownership of 'vconn'. */
632 rconn_add_monitor(struct rconn *rc, struct vconn *vconn)
634 if (rc->n_monitors < ARRAY_SIZE(rc->monitors)) {
635 VLOG_INFO("new monitor connection from %s", vconn_get_name(vconn));
636 rc->monitors[rc->n_monitors++] = vconn;
638 VLOG_DBG("too many monitor connections, discarding %s",
639 vconn_get_name(vconn));
644 /* Returns 'rc''s name. This is a name for human consumption, appropriate for
645 * use in log messages. It is not necessarily a name that may be passed
646 * directly to, e.g., vconn_open(). */
648 rconn_get_name(const struct rconn *rc)
653 /* Sets 'rc''s name to 'new_name'. */
655 rconn_set_name(struct rconn *rc, const char *new_name)
658 rc->name = xstrdup(new_name);
661 /* Returns 'rc''s target. This is intended to be a string that may be passed
662 * directly to, e.g., vconn_open(). */
664 rconn_get_target(const struct rconn *rc)
669 /* Returns true if 'rconn' is connected or in the process of reconnecting,
670 * false if 'rconn' is disconnected and will not reconnect on its own. */
672 rconn_is_alive(const struct rconn *rconn)
674 return rconn->state != S_VOID;
677 /* Returns true if 'rconn' is connected, false otherwise. */
679 rconn_is_connected(const struct rconn *rconn)
681 return is_connected_state(rconn->state);
684 /* Returns true if 'rconn' is connected and thought to have been accepted by
685 * the peer's admission-control policy. */
687 rconn_is_admitted(const struct rconn *rconn)
689 return (rconn_is_connected(rconn)
690 && rconn->last_admitted >= rconn->last_connected);
693 /* Returns 0 if 'rconn' is currently connected and considered to have been
694 * accepted by the peer's admission-control policy, otherwise the number of
695 * seconds since 'rconn' was last in such a state. */
697 rconn_failure_duration(const struct rconn *rconn)
699 return rconn_is_admitted(rconn) ? 0 : time_now() - rconn->last_admitted;
702 /* Returns the IP address of the peer, or 0 if the peer's IP address is not
705 rconn_get_remote_ip(const struct rconn *rconn)
707 return rconn->remote_ip;
710 /* Returns the transport port of the peer, or 0 if the peer's port is not
713 rconn_get_remote_port(const struct rconn *rconn)
715 return rconn->remote_port;
718 /* Returns the IP address used to connect to the peer, or 0 if the
719 * connection is not an IP-based protocol or if its IP address is not
722 rconn_get_local_ip(const struct rconn *rconn)
724 return rconn->local_ip;
727 /* Returns the transport port used to connect to the peer, or 0 if the
728 * connection does not contain a port or if the port is not known. */
730 rconn_get_local_port(const struct rconn *rconn)
732 return rconn->vconn ? vconn_get_local_port(rconn->vconn) : 0;
735 /* If 'rconn' can't connect to the peer, it could be for any number of reasons.
736 * Usually, one would assume it is because the peer is not running or because
737 * the network is partitioned. But it could also be because the network
738 * topology has changed, in which case the upper layer will need to reassess it
739 * (in particular, obtain a new IP address via DHCP and find the new location
740 * of the controller). When this appears that this might be the case, this
741 * function returns true. It also clears the questionability flag and prevents
742 * it from being set again for some time. */
744 rconn_is_connectivity_questionable(struct rconn *rconn)
746 bool questionable = rconn->questionable_connectivity;
747 rconn->questionable_connectivity = false;
751 /* Returns the total number of packets successfully received by the underlying
754 rconn_packets_received(const struct rconn *rc)
756 return rc->packets_received;
759 /* Returns a string representing the internal state of 'rc'. The caller must
760 * not modify or free the string. */
762 rconn_get_state(const struct rconn *rc)
764 return state_name(rc->state);
767 /* Returns the number of connection attempts made by 'rc', including any
768 * ongoing attempt that has not yet succeeded or failed. */
770 rconn_get_attempted_connections(const struct rconn *rc)
772 return rc->n_attempted_connections;
775 /* Returns the number of successful connection attempts made by 'rc'. */
777 rconn_get_successful_connections(const struct rconn *rc)
779 return rc->n_successful_connections;
782 /* Returns the time at which the last successful connection was made by
785 rconn_get_last_connection(const struct rconn *rc)
787 return rc->last_connected;
790 /* Returns the time at which the last OpenFlow message was received by 'rc'.
791 * If no packets have been received on 'rc', returns the time at which 'rc'
794 rconn_get_last_received(const struct rconn *rc)
796 return rc->last_received;
799 /* Returns the time at which 'rc' was created. */
801 rconn_get_creation_time(const struct rconn *rc)
803 return rc->creation_time;
806 /* Returns the approximate number of seconds that 'rc' has been connected. */
808 rconn_get_total_time_connected(const struct rconn *rc)
810 return (rc->total_time_connected
811 + (rconn_is_connected(rc) ? elapsed_in_this_state(rc) : 0));
814 /* Returns the current amount of backoff, in seconds. This is the amount of
815 * time after which the rconn will transition from BACKOFF to CONNECTING. */
817 rconn_get_backoff(const struct rconn *rc)
822 /* Returns the number of seconds spent in this state so far. */
824 rconn_get_state_elapsed(const struct rconn *rc)
826 return elapsed_in_this_state(rc);
829 /* Returns 'rc''s current connection sequence number, a number that changes
830 * every time that 'rconn' connects or disconnects. */
832 rconn_get_connection_seqno(const struct rconn *rc)
837 /* Returns a value that explains why 'rc' last disconnected:
839 * - 0 means that the last disconnection was caused by a call to
840 * rconn_disconnect(), or that 'rc' is new and has not yet completed its
841 * initial connection or connection attempt.
843 * - EOF means that the connection was closed in the normal way by the peer.
845 * - A positive integer is an errno value that represents the error.
848 rconn_get_last_error(const struct rconn *rc)
850 return rc->last_error;
853 struct rconn_packet_counter *
854 rconn_packet_counter_create(void)
856 struct rconn_packet_counter *c = xmalloc(sizeof *c);
863 rconn_packet_counter_destroy(struct rconn_packet_counter *c)
866 assert(c->ref_cnt > 0);
867 if (!--c->ref_cnt && !c->n) {
874 rconn_packet_counter_inc(struct rconn_packet_counter *c)
880 rconn_packet_counter_dec(struct rconn_packet_counter *c)
883 if (!--c->n && !c->ref_cnt) {
888 /* Set rc->target and rc->name to 'target' and 'name', respectively. If 'name'
889 * is null, 'target' is used.
891 * Also, clear out the cached IP address and port information, since changing
892 * the target also likely changes these values. */
894 rconn_set_target__(struct rconn *rc, const char *target, const char *name)
897 rc->name = xstrdup(name ? name : target);
899 rc->target = xstrdup(target);
905 /* Tries to send a packet from 'rc''s send buffer. Returns 0 if successful,
906 * otherwise a positive errno value. */
908 try_send(struct rconn *rc)
911 struct ofpbuf *next = rc->txq.head->next;
912 struct rconn_packet_counter *counter = rc->txq.head->private_p;
913 retval = vconn_send(rc->vconn, rc->txq.head);
915 if (retval != EAGAIN) {
916 report_error(rc, retval);
917 disconnect(rc, retval);
921 COVERAGE_INC(rconn_sent);
924 rconn_packet_counter_dec(counter);
926 queue_advance_head(&rc->txq, next);
930 /* Reports that 'error' caused 'rc' to disconnect. 'error' may be a positive
931 * errno value, or it may be EOF to indicate that the connection was closed
934 report_error(struct rconn *rc, int error)
937 /* If 'rc' isn't reliable, then we don't really expect this connection
938 * to last forever anyway (probably it's a connection that we received
939 * via accept()), so use DBG level to avoid cluttering the logs. */
940 enum vlog_level level = rc->reliable ? VLL_INFO : VLL_DBG;
941 VLOG(level, "%s: connection closed by peer", rc->name);
943 VLOG_WARN("%s: connection dropped (%s)", rc->name, strerror(error));
947 /* Disconnects 'rc' and records 'error' as the error that caused 'rc''s last
950 * - 0 means that this disconnection is due to a request by 'rc''s client,
951 * not due to any kind of network error.
953 * - EOF means that the connection was closed in the normal way by the peer.
955 * - A positive integer is an errno value that represents the error.
958 disconnect(struct rconn *rc, int error)
960 rc->last_error = error;
962 time_t now = time_now();
964 if (rc->state & (S_CONNECTING | S_ACTIVE | S_IDLE)) {
965 vconn_close(rc->vconn);
970 if (now >= rc->backoff_deadline) {
973 rc->backoff = MIN(rc->max_backoff, MAX(1, 2 * rc->backoff));
974 VLOG_INFO("%s: waiting %d seconds before reconnect\n",
975 rc->name, rc->backoff);
977 rc->backoff_deadline = now + rc->backoff;
978 state_transition(rc, S_BACKOFF);
979 if (now - rc->last_connected > 60) {
980 question_connectivity(rc);
983 rconn_disconnect(rc);
987 /* Drops all the packets from 'rc''s send queue and decrements their queue
990 flush_queue(struct rconn *rc)
995 while (rc->txq.n > 0) {
996 struct ofpbuf *b = queue_pop_head(&rc->txq);
997 struct rconn_packet_counter *counter = b->private_p;
999 rconn_packet_counter_dec(counter);
1001 COVERAGE_INC(rconn_discarded);
1004 poll_immediate_wake();
1008 elapsed_in_this_state(const struct rconn *rc)
1010 return time_now() - rc->state_entered;
1014 timeout(const struct rconn *rc)
1016 switch (rc->state) {
1017 #define STATE(NAME, VALUE) case S_##NAME: return timeout_##NAME(rc);
1026 timed_out(const struct rconn *rc)
1028 return time_now() >= sat_add(rc->state_entered, timeout(rc));
1032 state_transition(struct rconn *rc, enum state state)
1034 rc->seqno += (rc->state == S_ACTIVE) != (state == S_ACTIVE);
1035 if (is_connected_state(state) && !is_connected_state(rc->state)) {
1036 rc->probably_admitted = false;
1038 if (rconn_is_connected(rc)) {
1039 rc->total_time_connected += elapsed_in_this_state(rc);
1041 VLOG_DBG("%s: entering %s", rc->name, state_name(state));
1043 rc->state_entered = time_now();
1047 question_connectivity(struct rconn *rc)
1049 time_t now = time_now();
1050 if (now - rc->last_questioned > 60) {
1051 rc->questionable_connectivity = true;
1052 rc->last_questioned = now;
1057 copy_to_monitor(struct rconn *rc, const struct ofpbuf *b)
1059 struct ofpbuf *clone = NULL;
1063 for (i = 0; i < rc->n_monitors; ) {
1064 struct vconn *vconn = rc->monitors[i];
1067 clone = ofpbuf_clone(b);
1069 retval = vconn_send(vconn, clone);
1072 } else if (retval != EAGAIN) {
1073 VLOG_DBG("%s: closing monitor connection to %s: %s",
1074 rconn_get_name(rc), vconn_get_name(vconn),
1076 rc->monitors[i] = rc->monitors[--rc->n_monitors];
1081 ofpbuf_delete(clone);
1085 is_connected_state(enum state state)
1087 return (state & (S_ACTIVE | S_IDLE)) != 0;
1091 is_admitted_msg(const struct ofpbuf *b)
1093 struct ofp_header *oh = b->data;
1094 uint8_t type = oh->type;
1096 && (1u << type) & ((1u << OFPT_HELLO) |
1097 (1u << OFPT_ERROR) |
1098 (1u << OFPT_ECHO_REQUEST) |
1099 (1u << OFPT_ECHO_REPLY) |
1100 (1u << OFPT_VENDOR) |
1101 (1u << OFPT_FEATURES_REQUEST) |
1102 (1u << OFPT_FEATURES_REPLY) |
1103 (1u << OFPT_GET_CONFIG_REQUEST) |
1104 (1u << OFPT_GET_CONFIG_REPLY) |
1105 (1u << OFPT_SET_CONFIG)));