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"
35 VLOG_DEFINE_THIS_MODULE(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 *);
150 static bool rconn_logging_connection_attempts__(const struct rconn *);
152 /* Creates and returns a new rconn.
154 * 'probe_interval' is a number of seconds. If the interval passes once
155 * without an OpenFlow message being received from the peer, the rconn sends
156 * out an "echo request" message. If the interval passes again without a
157 * message being received, the rconn disconnects and re-connects to the peer.
158 * Setting 'probe_interval' to 0 disables this behavior.
160 * 'max_backoff' is the maximum number of seconds between attempts to connect
161 * to the peer. The actual interval starts at 1 second and doubles on each
162 * failure until it reaches 'max_backoff'. If 0 is specified, the default of
165 * The new rconn is initially unconnected. Use rconn_connect() or
166 * rconn_connect_unreliably() to connect it. */
168 rconn_create(int probe_interval, int max_backoff)
170 struct rconn *rc = xzalloc(sizeof *rc);
173 rc->state_entered = time_now();
176 rc->name = xstrdup("void");
177 rc->target = xstrdup("void");
178 rc->reliable = false;
180 queue_init(&rc->txq);
183 rc->max_backoff = max_backoff ? max_backoff : 8;
184 rc->backoff_deadline = TIME_MIN;
185 rc->last_received = time_now();
186 rc->last_connected = time_now();
189 rc->packets_sent = 0;
191 rc->probably_admitted = false;
192 rc->last_admitted = time_now();
194 rc->packets_received = 0;
195 rc->n_attempted_connections = 0;
196 rc->n_successful_connections = 0;
197 rc->creation_time = time_now();
198 rc->total_time_connected = 0;
200 rc->questionable_connectivity = false;
201 rc->last_questioned = time_now();
203 rconn_set_probe_interval(rc, probe_interval);
211 rconn_set_max_backoff(struct rconn *rc, int max_backoff)
213 rc->max_backoff = MAX(1, max_backoff);
214 if (rc->state == S_BACKOFF && rc->backoff > max_backoff) {
215 rc->backoff = max_backoff;
216 if (rc->backoff_deadline > time_now() + max_backoff) {
217 rc->backoff_deadline = time_now() + max_backoff;
223 rconn_get_max_backoff(const struct rconn *rc)
225 return rc->max_backoff;
229 rconn_set_probe_interval(struct rconn *rc, int probe_interval)
231 rc->probe_interval = probe_interval ? MAX(5, probe_interval) : 0;
235 rconn_get_probe_interval(const struct rconn *rc)
237 return rc->probe_interval;
240 /* Drops any existing connection on 'rc', then sets up 'rc' to connect to
241 * 'target' and reconnect as needed. 'target' should be a remote OpenFlow
242 * target in a form acceptable to vconn_open().
244 * If 'name' is nonnull, then it is used in log messages in place of 'target'.
245 * It should presumably give more information to a human reader than 'target',
246 * but it need not be acceptable to vconn_open(). */
248 rconn_connect(struct rconn *rc, const char *target, const char *name)
250 rconn_disconnect(rc);
251 rconn_set_target__(rc, target, name);
256 /* Drops any existing connection on 'rc', then configures 'rc' to use
257 * 'vconn'. If the connection on 'vconn' drops, 'rc' will not reconnect on it
260 * By default, the target obtained from vconn_get_name(vconn) is used in log
261 * messages. If 'name' is nonnull, then it is used instead. It should
262 * presumably give more information to a human reader than the target, but it
263 * need not be acceptable to vconn_open(). */
265 rconn_connect_unreliably(struct rconn *rc,
266 struct vconn *vconn, const char *name)
268 assert(vconn != NULL);
269 rconn_disconnect(rc);
270 rconn_set_target__(rc, vconn_get_name(vconn), name);
271 rc->reliable = false;
273 rc->last_connected = time_now();
274 state_transition(rc, S_ACTIVE);
277 /* If 'rc' is connected, forces it to drop the connection and reconnect. */
279 rconn_reconnect(struct rconn *rc)
281 if (rc->state & (S_ACTIVE | S_IDLE)) {
282 VLOG_INFO("%s: disconnecting", rc->name);
288 rconn_disconnect(struct rconn *rc)
290 if (rc->state != S_VOID) {
292 vconn_close(rc->vconn);
295 rconn_set_target__(rc, "void", NULL);
296 rc->reliable = false;
299 rc->backoff_deadline = TIME_MIN;
301 state_transition(rc, S_VOID);
305 /* Disconnects 'rc' and frees the underlying storage. */
307 rconn_destroy(struct rconn *rc)
314 vconn_close(rc->vconn);
316 queue_destroy(&rc->txq);
317 for (i = 0; i < rc->n_monitors; i++) {
318 vconn_close(rc->monitors[i]);
325 timeout_VOID(const struct rconn *rc OVS_UNUSED)
331 run_VOID(struct rconn *rc OVS_UNUSED)
337 reconnect(struct rconn *rc)
341 if (rconn_logging_connection_attempts__(rc)) {
342 VLOG_INFO("%s: connecting...", rc->name);
344 rc->n_attempted_connections++;
345 retval = vconn_open(rc->target, OFP_VERSION, &rc->vconn);
347 rc->remote_ip = vconn_get_remote_ip(rc->vconn);
348 rc->local_ip = vconn_get_local_ip(rc->vconn);
349 rc->remote_port = vconn_get_remote_port(rc->vconn);
350 rc->backoff_deadline = time_now() + rc->backoff;
351 state_transition(rc, S_CONNECTING);
353 VLOG_WARN("%s: connection failed (%s)", rc->name, strerror(retval));
354 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
355 disconnect(rc, retval);
360 timeout_BACKOFF(const struct rconn *rc)
366 run_BACKOFF(struct rconn *rc)
374 timeout_CONNECTING(const struct rconn *rc)
376 return MAX(1, rc->backoff);
380 run_CONNECTING(struct rconn *rc)
382 int retval = vconn_connect(rc->vconn);
384 VLOG_INFO("%s: connected", rc->name);
385 rc->n_successful_connections++;
386 state_transition(rc, S_ACTIVE);
387 rc->last_connected = rc->state_entered;
388 } else if (retval != EAGAIN) {
389 if (rconn_logging_connection_attempts__(rc)) {
390 VLOG_INFO("%s: connection failed (%s)",
391 rc->name, strerror(retval));
393 disconnect(rc, retval);
394 } else if (timed_out(rc)) {
395 if (rconn_logging_connection_attempts__(rc)) {
396 VLOG_INFO("%s: connection timed out", rc->name);
398 rc->backoff_deadline = TIME_MAX; /* Prevent resetting backoff. */
399 disconnect(rc, ETIMEDOUT);
404 do_tx_work(struct rconn *rc)
409 while (rc->txq.n > 0) {
410 int error = try_send(rc);
416 poll_immediate_wake();
421 timeout_ACTIVE(const struct rconn *rc)
423 if (rc->probe_interval) {
424 unsigned int base = MAX(rc->last_received, rc->state_entered);
425 unsigned int arg = base + rc->probe_interval - rc->state_entered;
432 run_ACTIVE(struct rconn *rc)
435 unsigned int base = MAX(rc->last_received, rc->state_entered);
436 VLOG_DBG("%s: idle %u seconds, sending inactivity probe",
437 rc->name, (unsigned int) (time_now() - base));
439 /* Ordering is important here: rconn_send() can transition to BACKOFF,
440 * and we don't want to transition back to IDLE if so, because then we
441 * can end up queuing a packet with vconn == NULL and then *boom*. */
442 state_transition(rc, S_IDLE);
443 rconn_send(rc, make_echo_request(), NULL);
451 timeout_IDLE(const struct rconn *rc)
453 return rc->probe_interval;
457 run_IDLE(struct rconn *rc)
460 question_connectivity(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);
509 for (i = 0; i < rc->n_monitors; i++) {
510 vconn_run_wait(rc->monitors[i]);
514 if (timeo != UINT_MAX) {
515 long long int expires = sat_add(rc->state_entered, timeo);
516 poll_timer_wait_until(expires * 1000);
519 if ((rc->state & (S_ACTIVE | S_IDLE)) && rc->txq.n) {
520 vconn_wait(rc->vconn, WAIT_SEND);
524 /* Attempts to receive a packet from 'rc'. If successful, returns the packet;
525 * otherwise, returns a null pointer. The caller is responsible for freeing
526 * the packet (with ofpbuf_delete()). */
528 rconn_recv(struct rconn *rc)
530 if (rc->state & (S_ACTIVE | S_IDLE)) {
531 struct ofpbuf *buffer;
532 int error = vconn_recv(rc->vconn, &buffer);
534 copy_to_monitor(rc, buffer);
535 if (rc->probably_admitted || is_admitted_msg(buffer)
536 || time_now() - rc->last_connected >= 30) {
537 rc->probably_admitted = true;
538 rc->last_admitted = time_now();
540 rc->last_received = time_now();
541 rc->packets_received++;
542 if (rc->state == S_IDLE) {
543 state_transition(rc, S_ACTIVE);
546 } else if (error != EAGAIN) {
547 report_error(rc, error);
548 disconnect(rc, error);
554 /* Causes the next call to poll_block() to wake up when a packet may be ready
555 * to be received by vconn_recv() on 'rc'. */
557 rconn_recv_wait(struct rconn *rc)
560 vconn_wait(rc->vconn, WAIT_RECV);
564 /* Sends 'b' on 'rc'. Returns 0 if successful (in which case 'b' is
565 * destroyed), or ENOTCONN if 'rc' is not currently connected (in which case
566 * the caller retains ownership of 'b').
568 * If 'counter' is non-null, then 'counter' will be incremented while the
569 * packet is in flight, then decremented when it has been sent (or discarded
570 * due to disconnection). Because 'b' may be sent (or discarded) before this
571 * function returns, the caller may not be able to observe any change in
574 * There is no rconn_send_wait() function: an rconn has a send queue that it
575 * takes care of sending if you call rconn_run(), which will have the side
576 * effect of waking up poll_block(). */
578 rconn_send(struct rconn *rc, struct ofpbuf *b,
579 struct rconn_packet_counter *counter)
581 if (rconn_is_connected(rc)) {
582 COVERAGE_INC(rconn_queued);
583 copy_to_monitor(rc, b);
584 b->private_p = counter;
586 rconn_packet_counter_inc(counter);
588 queue_push_tail(&rc->txq, b);
590 /* If the queue was empty before we added 'b', try to send some
591 * packets. (But if the queue had packets in it, it's because the
592 * vconn is backlogged and there's no point in stuffing more into it
593 * now. We'll get back to that in rconn_run().) */
594 if (rc->txq.n == 1) {
603 /* Sends 'b' on 'rc'. Increments 'counter' while the packet is in flight; it
604 * will be decremented when it has been sent (or discarded due to
605 * disconnection). Returns 0 if successful, EAGAIN if 'counter->n' is already
606 * at least as large as 'queue_limit', or ENOTCONN if 'rc' is not currently
607 * connected. Regardless of return value, 'b' is destroyed.
609 * Because 'b' may be sent (or discarded) before this function returns, the
610 * caller may not be able to observe any change in 'counter'.
612 * There is no rconn_send_wait() function: an rconn has a send queue that it
613 * takes care of sending if you call rconn_run(), which will have the side
614 * effect of waking up poll_block(). */
616 rconn_send_with_limit(struct rconn *rc, struct ofpbuf *b,
617 struct rconn_packet_counter *counter, int queue_limit)
620 retval = counter->n >= queue_limit ? EAGAIN : rconn_send(rc, b, counter);
622 COVERAGE_INC(rconn_overflow);
628 /* Returns the total number of packets successfully sent on the underlying
629 * vconn. A packet is not counted as sent while it is still queued in the
630 * rconn, only when it has been successfuly passed to the vconn. */
632 rconn_packets_sent(const struct rconn *rc)
634 return rc->packets_sent;
637 /* Adds 'vconn' to 'rc' as a monitoring connection, to which all messages sent
638 * and received on 'rconn' will be copied. 'rc' takes ownership of 'vconn'. */
640 rconn_add_monitor(struct rconn *rc, struct vconn *vconn)
642 if (rc->n_monitors < ARRAY_SIZE(rc->monitors)) {
643 VLOG_INFO("new monitor connection from %s", vconn_get_name(vconn));
644 rc->monitors[rc->n_monitors++] = vconn;
646 VLOG_DBG("too many monitor connections, discarding %s",
647 vconn_get_name(vconn));
652 /* Returns 'rc''s name. This is a name for human consumption, appropriate for
653 * use in log messages. It is not necessarily a name that may be passed
654 * directly to, e.g., vconn_open(). */
656 rconn_get_name(const struct rconn *rc)
661 /* Sets 'rc''s name to 'new_name'. */
663 rconn_set_name(struct rconn *rc, const char *new_name)
666 rc->name = xstrdup(new_name);
669 /* Returns 'rc''s target. This is intended to be a string that may be passed
670 * directly to, e.g., vconn_open(). */
672 rconn_get_target(const struct rconn *rc)
677 /* Returns true if 'rconn' is connected or in the process of reconnecting,
678 * false if 'rconn' is disconnected and will not reconnect on its own. */
680 rconn_is_alive(const struct rconn *rconn)
682 return rconn->state != S_VOID;
685 /* Returns true if 'rconn' is connected, false otherwise. */
687 rconn_is_connected(const struct rconn *rconn)
689 return is_connected_state(rconn->state);
692 /* Returns true if 'rconn' is connected and thought to have been accepted by
693 * the peer's admission-control policy. */
695 rconn_is_admitted(const struct rconn *rconn)
697 return (rconn_is_connected(rconn)
698 && rconn->last_admitted >= rconn->last_connected);
701 /* Returns 0 if 'rconn' is currently connected and considered to have been
702 * accepted by the peer's admission-control policy, otherwise the number of
703 * seconds since 'rconn' was last in such a state. */
705 rconn_failure_duration(const struct rconn *rconn)
707 return rconn_is_admitted(rconn) ? 0 : time_now() - rconn->last_admitted;
710 /* Returns the IP address of the peer, or 0 if the peer's IP address is not
713 rconn_get_remote_ip(const struct rconn *rconn)
715 return rconn->remote_ip;
718 /* Returns the transport port of the peer, or 0 if the peer's port is not
721 rconn_get_remote_port(const struct rconn *rconn)
723 return rconn->remote_port;
726 /* Returns the IP address used to connect to the peer, or 0 if the
727 * connection is not an IP-based protocol or if its IP address is not
730 rconn_get_local_ip(const struct rconn *rconn)
732 return rconn->local_ip;
735 /* Returns the transport port used to connect to the peer, or 0 if the
736 * connection does not contain a port or if the port is not known. */
738 rconn_get_local_port(const struct rconn *rconn)
740 return rconn->vconn ? vconn_get_local_port(rconn->vconn) : 0;
743 /* If 'rconn' can't connect to the peer, it could be for any number of reasons.
744 * Usually, one would assume it is because the peer is not running or because
745 * the network is partitioned. But it could also be because the network
746 * topology has changed, in which case the upper layer will need to reassess it
747 * (in particular, obtain a new IP address via DHCP and find the new location
748 * of the controller). When this appears that this might be the case, this
749 * function returns true. It also clears the questionability flag and prevents
750 * it from being set again for some time. */
752 rconn_is_connectivity_questionable(struct rconn *rconn)
754 bool questionable = rconn->questionable_connectivity;
755 rconn->questionable_connectivity = false;
759 /* Returns the total number of packets successfully received by the underlying
762 rconn_packets_received(const struct rconn *rc)
764 return rc->packets_received;
767 /* Returns a string representing the internal state of 'rc'. The caller must
768 * not modify or free the string. */
770 rconn_get_state(const struct rconn *rc)
772 return state_name(rc->state);
775 /* Returns the number of connection attempts made by 'rc', including any
776 * ongoing attempt that has not yet succeeded or failed. */
778 rconn_get_attempted_connections(const struct rconn *rc)
780 return rc->n_attempted_connections;
783 /* Returns the number of successful connection attempts made by 'rc'. */
785 rconn_get_successful_connections(const struct rconn *rc)
787 return rc->n_successful_connections;
790 /* Returns the time at which the last successful connection was made by
793 rconn_get_last_connection(const struct rconn *rc)
795 return rc->last_connected;
798 /* Returns the time at which the last OpenFlow message was received by 'rc'.
799 * If no packets have been received on 'rc', returns the time at which 'rc'
802 rconn_get_last_received(const struct rconn *rc)
804 return rc->last_received;
807 /* Returns the time at which 'rc' was created. */
809 rconn_get_creation_time(const struct rconn *rc)
811 return rc->creation_time;
814 /* Returns the approximate number of seconds that 'rc' has been connected. */
816 rconn_get_total_time_connected(const struct rconn *rc)
818 return (rc->total_time_connected
819 + (rconn_is_connected(rc) ? elapsed_in_this_state(rc) : 0));
822 /* Returns the current amount of backoff, in seconds. This is the amount of
823 * time after which the rconn will transition from BACKOFF to CONNECTING. */
825 rconn_get_backoff(const struct rconn *rc)
830 /* Returns the number of seconds spent in this state so far. */
832 rconn_get_state_elapsed(const struct rconn *rc)
834 return elapsed_in_this_state(rc);
837 /* Returns 'rc''s current connection sequence number, a number that changes
838 * every time that 'rconn' connects or disconnects. */
840 rconn_get_connection_seqno(const struct rconn *rc)
845 /* Returns a value that explains why 'rc' last disconnected:
847 * - 0 means that the last disconnection was caused by a call to
848 * rconn_disconnect(), or that 'rc' is new and has not yet completed its
849 * initial connection or connection attempt.
851 * - EOF means that the connection was closed in the normal way by the peer.
853 * - A positive integer is an errno value that represents the error.
856 rconn_get_last_error(const struct rconn *rc)
858 return rc->last_error;
861 struct rconn_packet_counter *
862 rconn_packet_counter_create(void)
864 struct rconn_packet_counter *c = xmalloc(sizeof *c);
871 rconn_packet_counter_destroy(struct rconn_packet_counter *c)
874 assert(c->ref_cnt > 0);
875 if (!--c->ref_cnt && !c->n) {
882 rconn_packet_counter_inc(struct rconn_packet_counter *c)
888 rconn_packet_counter_dec(struct rconn_packet_counter *c)
891 if (!--c->n && !c->ref_cnt) {
896 /* Set rc->target and rc->name to 'target' and 'name', respectively. If 'name'
897 * is null, 'target' is used.
899 * Also, clear out the cached IP address and port information, since changing
900 * the target also likely changes these values. */
902 rconn_set_target__(struct rconn *rc, const char *target, const char *name)
905 rc->name = xstrdup(name ? name : target);
907 rc->target = xstrdup(target);
913 /* Tries to send a packet from 'rc''s send buffer. Returns 0 if successful,
914 * otherwise a positive errno value. */
916 try_send(struct rconn *rc)
919 struct ofpbuf *next = rc->txq.head->next;
920 struct rconn_packet_counter *counter = rc->txq.head->private_p;
921 retval = vconn_send(rc->vconn, rc->txq.head);
923 if (retval != EAGAIN) {
924 report_error(rc, retval);
925 disconnect(rc, retval);
929 COVERAGE_INC(rconn_sent);
932 rconn_packet_counter_dec(counter);
934 queue_advance_head(&rc->txq, next);
938 /* Reports that 'error' caused 'rc' to disconnect. 'error' may be a positive
939 * errno value, or it may be EOF to indicate that the connection was closed
942 report_error(struct rconn *rc, int error)
945 /* If 'rc' isn't reliable, then we don't really expect this connection
946 * to last forever anyway (probably it's a connection that we received
947 * via accept()), so use DBG level to avoid cluttering the logs. */
948 enum vlog_level level = rc->reliable ? VLL_INFO : VLL_DBG;
949 VLOG(level, "%s: connection closed by peer", rc->name);
951 VLOG_WARN("%s: connection dropped (%s)", rc->name, strerror(error));
955 /* Disconnects 'rc' and records 'error' as the error that caused 'rc''s last
958 * - 0 means that this disconnection is due to a request by 'rc''s client,
959 * not due to any kind of network error.
961 * - EOF means that the connection was closed in the normal way by the peer.
963 * - A positive integer is an errno value that represents the error.
966 disconnect(struct rconn *rc, int error)
968 rc->last_error = error;
970 time_t now = time_now();
972 if (rc->state & (S_CONNECTING | S_ACTIVE | S_IDLE)) {
973 vconn_close(rc->vconn);
978 if (now >= rc->backoff_deadline) {
980 } else if (rc->backoff < rc->max_backoff / 2) {
981 rc->backoff = MAX(1, 2 * rc->backoff);
982 VLOG_INFO("%s: waiting %d seconds before reconnect",
983 rc->name, rc->backoff);
985 if (rconn_logging_connection_attempts__(rc)) {
986 VLOG_INFO("%s: continuing to retry connections in the "
987 "background but suppressing further logging",
990 rc->backoff = rc->max_backoff;
992 rc->backoff_deadline = now + rc->backoff;
993 state_transition(rc, S_BACKOFF);
994 if (now - rc->last_connected > 60) {
995 question_connectivity(rc);
998 rconn_disconnect(rc);
1002 /* Drops all the packets from 'rc''s send queue and decrements their queue
1005 flush_queue(struct rconn *rc)
1010 while (rc->txq.n > 0) {
1011 struct ofpbuf *b = queue_pop_head(&rc->txq);
1012 struct rconn_packet_counter *counter = b->private_p;
1014 rconn_packet_counter_dec(counter);
1016 COVERAGE_INC(rconn_discarded);
1019 poll_immediate_wake();
1023 elapsed_in_this_state(const struct rconn *rc)
1025 return time_now() - rc->state_entered;
1029 timeout(const struct rconn *rc)
1031 switch (rc->state) {
1032 #define STATE(NAME, VALUE) case S_##NAME: return timeout_##NAME(rc);
1041 timed_out(const struct rconn *rc)
1043 return time_now() >= sat_add(rc->state_entered, timeout(rc));
1047 state_transition(struct rconn *rc, enum state state)
1049 rc->seqno += (rc->state == S_ACTIVE) != (state == S_ACTIVE);
1050 if (is_connected_state(state) && !is_connected_state(rc->state)) {
1051 rc->probably_admitted = false;
1053 if (rconn_is_connected(rc)) {
1054 rc->total_time_connected += elapsed_in_this_state(rc);
1056 VLOG_DBG("%s: entering %s", rc->name, state_name(state));
1058 rc->state_entered = time_now();
1062 question_connectivity(struct rconn *rc)
1064 time_t now = time_now();
1065 if (now - rc->last_questioned > 60) {
1066 rc->questionable_connectivity = true;
1067 rc->last_questioned = 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;