2 * Copyright (c) 2008, 2009, 2010, 2011 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.
26 #include "dynamic-string.h"
35 #include "poll-loop.h"
41 VLOG_DEFINE_THIS_MODULE(bond);
43 /* Bit-mask for hashing a flow down to a bucket.
44 * There are (BOND_MASK + 1) buckets. */
45 #define BOND_MASK 0xff
47 /* A hash bucket for mapping a flow to a slave.
48 * "struct bond" has an array of (BOND_MASK + 1) of these. */
50 struct bond_slave *slave; /* Assigned slave, NULL if unassigned. */
51 uint64_t tx_bytes; /* Count of bytes recently transmitted. */
52 tag_type tag; /* Tag for entry<->slave association. */
53 struct list list_node; /* In bond_slave's 'entries' list. */
56 /* A bond slave, that is, one of the links comprising a bond. */
58 struct hmap_node hmap_node; /* In struct bond's slaves hmap. */
59 struct bond *bond; /* The bond that contains this slave. */
60 void *aux; /* Client-provided handle for this slave. */
62 struct netdev *netdev; /* Network device, owned by the client. */
63 char *name; /* Name (a copy of netdev_get_name(netdev)). */
66 long long delay_expires; /* Time after which 'enabled' may change. */
67 bool up; /* Last link status read from netdev. */
68 bool enabled; /* May be chosen for flows? */
69 tag_type tag; /* Tag associated with this slave. */
71 /* Rebalancing info. Used only by bond_rebalance(). */
72 struct list bal_node; /* In bond_rebalance()'s 'bals' list. */
73 struct list entries; /* 'struct bond_entry's assigned here. */
74 uint64_t tx_bytes; /* Sum across 'tx_bytes' of entries. */
76 /* BM_STABLE specific bonding info. */
77 uint16_t stb_id; /* ID used for 'stb_slaves' ordering. */
78 size_t stb_idx; /* Index in 'bond''s 'stb_slaves' array.
79 Undefined value if participating in a
80 BTM_STABLE bond or not enabled. */
83 /* A bond, that is, a set of network devices grouped to improve performance or
86 struct hmap_node hmap_node; /* In 'all_bonds' hmap. */
87 char *name; /* Name provided by client. */
93 enum bond_mode balance; /* Balancing mode, one of BM_*. */
94 struct bond_slave *active_slave;
95 tag_type no_slaves_tag; /* Tag for flows when all slaves disabled. */
96 int updelay, downdelay; /* Delay before slave goes up/down, in ms. */
98 /* SLB specific bonding info. */
99 struct bond_entry *hash; /* An array of (BOND_MASK + 1) elements. */
100 int rebalance_interval; /* Interval between rebalances, in ms. */
101 long long int next_rebalance; /* Next rebalancing time. */
102 bool send_learning_packets;
104 /* BM_STABLE specific bonding info. */
105 struct bond_slave **stb_slaves; /* Ordered list of enabled slaves. */
106 size_t n_stb_slaves; /* Number of slaves in 'stb_slaves'. */
107 size_t len_stb_slaves; /* Slaves allocated in 'stb_slaves'. */
108 bool stb_need_sort; /* True if stb_slaves is not sorted. */
111 const struct lacp *lacp; /* Client provided LACP handle. */
114 enum bond_detect_mode detect; /* Link status mode, one of BLSM_*. */
115 struct netdev_monitor *monitor; /* detect == BLSM_CARRIER only. */
116 long long int miimon_interval; /* Miimon status refresh interval. */
117 long long int miimon_next_update; /* Time of next miimon update. */
119 /* Legacy compatibility. */
120 long long int next_fake_iface_update; /* LLONG_MAX if disabled. */
122 /* Tag set saved for next bond_run(). This tag set is a kluge for cases
123 * where we can't otherwise provide revalidation feedback to the client.
124 * That's only unixctl commands now; I hope no other cases will arise. */
125 struct tag_set unixctl_tags;
128 static struct hmap all_bonds = HMAP_INITIALIZER(&all_bonds);
130 static void bond_entry_reset(struct bond *);
131 static struct bond_slave *bond_slave_lookup(struct bond *, const void *slave_);
132 static bool bond_is_link_up(struct bond *, struct netdev *);
133 static void bond_enable_slave(struct bond_slave *, bool enable,
135 static bool bond_stb_sort(struct bond *);
136 static void bond_stb_enable_slave(struct bond_slave *);
137 static void bond_link_status_update(struct bond_slave *, struct tag_set *);
138 static void bond_choose_active_slave(struct bond *, struct tag_set *);
139 static bool bond_is_tcp_hash(const struct bond *);
140 static unsigned int bond_hash_src(const uint8_t mac[ETH_ADDR_LEN],
142 static unsigned int bond_hash_tcp(const struct flow *, uint16_t vlan);
143 static struct bond_entry *lookup_bond_entry(const struct bond *,
146 static tag_type bond_get_active_slave_tag(const struct bond *);
147 static struct bond_slave *choose_output_slave(const struct bond *,
150 static void bond_update_fake_slave_stats(struct bond *);
152 /* Attempts to parse 's' as the name of a bond balancing mode. If successful,
153 * stores the mode in '*balance' and returns true. Otherwise returns false
154 * without modifying '*balance'. */
156 bond_mode_from_string(enum bond_mode *balance, const char *s)
158 if (!strcmp(s, bond_mode_to_string(BM_TCP))) {
160 } else if (!strcmp(s, bond_mode_to_string(BM_SLB))) {
162 } else if (!strcmp(s, bond_mode_to_string(BM_STABLE))) {
163 *balance = BM_STABLE;
164 } else if (!strcmp(s, bond_mode_to_string(BM_AB))) {
172 /* Returns a string representing 'balance'. */
174 bond_mode_to_string(enum bond_mode balance) {
177 return "balance-tcp";
179 return "balance-slb";
183 return "active-backup";
188 /* Attempts to parse 's' as the name of a bond link status detection mode. If
189 * successful, stores the mode in '*detect' and returns true. Otherwise
190 * returns false without modifying '*detect'. */
192 bond_detect_mode_from_string(enum bond_detect_mode *detect, const char *s)
194 if (!strcmp(s, bond_detect_mode_to_string(BLSM_CARRIER))) {
195 *detect = BLSM_CARRIER;
196 } else if (!strcmp(s, bond_detect_mode_to_string(BLSM_MIIMON))) {
197 *detect = BLSM_MIIMON;
204 /* Returns a string representing 'detect'. */
206 bond_detect_mode_to_string(enum bond_detect_mode detect)
217 /* Creates and returns a new bond whose configuration is initially taken from
220 * The caller should register each slave on the new bond by calling
221 * bond_slave_register(). */
223 bond_create(const struct bond_settings *s)
227 bond = xzalloc(sizeof *bond);
228 hmap_init(&bond->slaves);
229 bond->no_slaves_tag = tag_create_random();
230 bond->miimon_next_update = LLONG_MAX;
231 bond->next_fake_iface_update = LLONG_MAX;
233 bond_reconfigure(bond, s);
235 tag_set_init(&bond->unixctl_tags);
242 bond_destroy(struct bond *bond)
244 struct bond_slave *slave, *next_slave;
250 hmap_remove(&all_bonds, &bond->hmap_node);
252 HMAP_FOR_EACH_SAFE (slave, next_slave, hmap_node, &bond->slaves) {
253 hmap_remove(&bond->slaves, &slave->hmap_node);
254 /* Client owns 'slave->netdev'. */
258 hmap_destroy(&bond->slaves);
262 netdev_monitor_destroy(bond->monitor);
268 /* Updates 'bond''s overall configuration to 's'.
270 * The caller should register each slave on 'bond' by calling
271 * bond_slave_register(). This is optional if none of the slaves'
272 * configuration has changed, except that it is mandatory if 's' enables LACP
273 * and 'bond' previously didn't have LACP enabled. In any case it can't
276 * Returns true if the configuration has changed in such a way that requires
280 bond_reconfigure(struct bond *bond, const struct bond_settings *s)
282 bool revalidate = false;
284 if (!bond->name || strcmp(bond->name, s->name)) {
286 hmap_remove(&all_bonds, &bond->hmap_node);
289 bond->name = xstrdup(s->name);
290 hmap_insert(&all_bonds, &bond->hmap_node, hash_string(bond->name, 0));
293 bond->lacp = s->lacp;
294 bond->detect = s->detect;
295 bond->miimon_interval = s->miimon_interval;
296 bond->updelay = s->up_delay;
297 bond->downdelay = s->down_delay;
298 bond->rebalance_interval = s->rebalance_interval;
300 if (bond->balance != s->balance) {
301 bond->balance = s->balance;
305 if (bond->detect == BLSM_CARRIER) {
306 struct bond_slave *slave;
308 if (!bond->monitor) {
309 bond->monitor = netdev_monitor_create();
312 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
313 netdev_monitor_add(bond->monitor, slave->netdev);
316 netdev_monitor_destroy(bond->monitor);
317 bond->monitor = NULL;
319 if (bond->miimon_next_update == LLONG_MAX) {
320 bond->miimon_next_update = time_msec() + bond->miimon_interval;
325 if (bond->next_fake_iface_update == LLONG_MAX) {
326 bond->next_fake_iface_update = time_msec();
329 bond->next_fake_iface_update = LLONG_MAX;
332 if (bond->balance != BM_STABLE) {
333 free(bond->stb_slaves);
334 bond->stb_slaves = NULL;
335 } else if (!bond->stb_slaves) {
336 struct bond_slave *slave;
338 bond->n_stb_slaves = 0;
339 bond->len_stb_slaves = 0;
340 bond->stb_slaves = NULL;
342 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
343 if (slave->enabled) {
344 bond_stb_enable_slave(slave);
349 if (bond->balance == BM_AB || !bond->hash || revalidate) {
350 bond_entry_reset(bond);
356 /* Registers 'slave_' as a slave of 'bond'. The 'slave_' pointer is an
357 * arbitrary client-provided pointer that uniquely identifies a slave within a
358 * bond. If 'slave_' already exists within 'bond' then this function
359 * reconfigures the existing slave.
361 * 'stb_id' is used in BM_STABLE bonds to guarantee consistent slave choices
362 * across restarts and distributed vswitch instances. It should be unique per
363 * slave, and preferably consistent across restarts and reconfigurations.
365 * 'netdev' must be the network device that 'slave_' represents. It is owned
366 * by the client, so the client must not close it before either unregistering
367 * 'slave_' or destroying 'bond'.
369 * If 'bond' has a LACP configuration then 'slave_' should be the same handle
370 * used in the LACP module. */
372 bond_slave_register(struct bond *bond, void *slave_, uint16_t stb_id,
373 struct netdev *netdev)
375 struct bond_slave *slave = bond_slave_lookup(bond, slave_);
378 slave = xzalloc(sizeof *slave);
380 hmap_insert(&bond->slaves, &slave->hmap_node, hash_pointer(slave_, 0));
383 slave->delay_expires = LLONG_MAX;
384 slave->up = bond_is_link_up(bond, netdev);
385 slave->enabled = false;
386 bond_enable_slave(slave, slave->up, NULL);
389 if (slave->stb_id != stb_id) {
390 bond->stb_need_sort = true;
391 slave->stb_id = stb_id;
394 slave->netdev = netdev;
396 slave->name = xstrdup(netdev_get_name(netdev));
399 /* Unregisters 'slave_' from 'bond'. If 'bond' does not contain such a slave
400 * then this function has no effect.
402 * Unregistering a slave invalidates all flows. */
404 bond_slave_unregister(struct bond *bond, const void *slave_)
406 struct bond_slave *slave = bond_slave_lookup(bond, slave_);
413 bond_enable_slave(slave, false, NULL);
415 del_active = bond->active_slave == slave;
417 struct bond_entry *e;
418 for (e = bond->hash; e <= &bond->hash[BOND_MASK]; e++) {
419 if (e->slave == slave) {
427 hmap_remove(&bond->slaves, &slave->hmap_node);
428 /* Client owns 'slave->netdev'. */
435 bond_choose_active_slave(bond, &tags);
436 bond->send_learning_packets = true;
440 /* Performs periodic maintenance on 'bond'. The caller must provide 'tags' to
441 * allow tagged flows to be invalidated.
443 * The caller should check bond_should_send_learning_packets() afterward. */
445 bond_run(struct bond *bond, struct tag_set *tags)
447 struct bond_slave *slave;
448 bool is_tcp_hash = bond_is_tcp_hash(bond);
450 /* Update link status. */
451 if (bond->detect == BLSM_CARRIER
452 || time_msec() >= bond->miimon_next_update)
454 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
455 slave->up = bond_is_link_up(bond, slave->netdev);
457 bond->miimon_next_update = time_msec() + bond->miimon_interval;
460 /* Enable slaves based on link status and LACP feedback. */
461 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
462 bond_link_status_update(slave, tags);
464 if (!bond->active_slave || !bond->active_slave->enabled) {
465 bond_choose_active_slave(bond, tags);
468 /* Update fake bond interface stats. */
469 if (time_msec() >= bond->next_fake_iface_update) {
470 bond_update_fake_slave_stats(bond);
471 bond->next_fake_iface_update = time_msec() + 1000;
474 if (bond_stb_sort(bond) || is_tcp_hash != bond_is_tcp_hash(bond)) {
475 struct bond_slave *slave;
477 bond_entry_reset(bond);
478 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
479 tag_set_add(tags, slave->tag);
483 /* Invalidate any tags required by */
484 tag_set_union(tags, &bond->unixctl_tags);
485 tag_set_init(&bond->unixctl_tags);
488 /* Causes poll_block() to wake up when 'bond' needs something to be done. */
490 bond_wait(struct bond *bond)
492 struct bond_slave *slave;
494 if (bond->detect == BLSM_CARRIER) {
495 netdev_monitor_poll_wait(bond->monitor);
497 poll_timer_wait_until(bond->miimon_next_update);
500 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
501 if (slave->delay_expires != LLONG_MAX) {
502 poll_timer_wait_until(slave->delay_expires);
506 if (bond->next_fake_iface_update != LLONG_MAX) {
507 poll_timer_wait_until(bond->next_fake_iface_update);
510 /* Ensure that any saved tags get revalidated right away. */
511 if (!tag_set_is_empty(&bond->unixctl_tags)) {
512 poll_immediate_wake();
515 /* We don't wait for bond->next_rebalance because rebalancing can only run
516 * at a flow account checkpoint. ofproto does checkpointing on its own
517 * schedule and bond_rebalance() gets called afterward, so we'd just be
518 * waking up for no purpose. */
521 /* MAC learning table interaction. */
524 may_send_learning_packets(const struct bond *bond)
526 return !lacp_negotiated(bond->lacp) && bond->balance != BM_AB;
529 /* Returns true if 'bond' needs the client to send out packets to assist with
530 * MAC learning on 'bond'. If this function returns true, then the client
531 * should iterate through its MAC learning table for the bridge on which 'bond'
532 * is located. For each MAC that has been learned on a port other than 'bond',
533 * it should call bond_send_learning_packet().
535 * This function will only return true if 'bond' is in SLB mode and LACP is not
536 * negotiated. Otherwise sending learning packets isn't necessary.
538 * Calling this function resets the state that it checks. */
540 bond_should_send_learning_packets(struct bond *bond)
542 bool send = bond->send_learning_packets && may_send_learning_packets(bond);
543 bond->send_learning_packets = false;
547 /* Sends a gratuitous learning packet on 'bond' from 'eth_src' on 'vlan'.
549 * See bond_should_send_learning_packets() for description of usage. */
551 bond_send_learning_packet(struct bond *bond,
552 const uint8_t eth_src[ETH_ADDR_LEN],
555 struct bond_slave *slave;
556 struct ofpbuf packet;
560 assert(may_send_learning_packets(bond));
561 if (!bond->active_slave) {
562 /* Nowhere to send the learning packet. */
566 memset(&flow, 0, sizeof flow);
567 memcpy(flow.dl_src, eth_src, ETH_ADDR_LEN);
568 slave = choose_output_slave(bond, &flow, vlan);
570 ofpbuf_init(&packet, 0);
571 compose_benign_packet(&packet, "Open vSwitch Bond Failover", 0xf177,
574 eth_set_vlan_tci(&packet, htons(vlan));
576 error = netdev_send(slave->netdev, &packet);
577 ofpbuf_uninit(&packet);
582 /* Checks whether a packet that arrived on 'slave_' within 'bond', with an
583 * Ethernet destination address of 'eth_dst', should be admitted.
585 * The return value is one of the following:
587 * - BV_ACCEPT: Admit the packet.
589 * - BV_DROP: Drop the packet.
591 * - BV_DROP_IF_MOVED: Consult the MAC learning table for the packet's
592 * Ethernet source address and VLAN. If there is none, or if the packet
593 * is on the learned port, then admit the packet. If a different port has
594 * been learned, however, drop the packet (and do not use it for MAC
598 bond_check_admissibility(struct bond *bond, const void *slave_,
599 const uint8_t eth_dst[ETH_ADDR_LEN], tag_type *tags)
601 /* Admit all packets if LACP has been negotiated, because that means that
602 * the remote switch is aware of the bond and will "do the right thing". */
603 if (lacp_negotiated(bond->lacp)) {
607 /* Drop all multicast packets on inactive slaves. */
608 if (eth_addr_is_multicast(eth_dst)) {
609 *tags |= bond_get_active_slave_tag(bond);
610 if (bond->active_slave != bond_slave_lookup(bond, slave_)) {
615 /* Drop all packets for which we have learned a different input port,
616 * because we probably sent the packet on one slave and got it back on the
617 * other. Gratuitous ARP packets are an exception to this rule: the host
618 * has moved to another switch. The exception to the exception is if we
619 * locked the learning table to avoid reflections on bond slaves. */
620 return BV_DROP_IF_MOVED;
623 /* Returns the slave (registered on 'bond' by bond_slave_register()) to which
624 * a packet with the given 'flow' and 'vlan' should be forwarded. Returns
625 * NULL if the packet should be dropped because no slaves are enabled.
627 * 'vlan' is not necessarily the same as 'flow->vlan_tci'. First, 'vlan'
628 * should be a VID only (i.e. excluding the PCP bits). Second,
629 * 'flow->vlan_tci' is the VLAN TCI that appeared on the packet (so it will be
630 * nonzero only for trunk ports), whereas 'vlan' is the logical VLAN that the
631 * packet belongs to (so for an access port it will be the access port's VLAN).
633 * Adds a tag to '*tags' that associates the flow with the returned slave.
636 bond_choose_output_slave(struct bond *bond, const struct flow *flow,
637 uint16_t vlan, tag_type *tags)
639 struct bond_slave *slave = choose_output_slave(bond, flow, vlan);
644 *tags |= bond->no_slaves_tag;
652 bond_is_balanced(const struct bond *bond)
654 return bond->balance == BM_SLB || bond->balance == BM_TCP;
657 /* Notifies 'bond' that 'n_bytes' bytes were sent in 'flow' within 'vlan'. */
659 bond_account(struct bond *bond, const struct flow *flow, uint16_t vlan,
663 if (bond_is_balanced(bond)) {
664 lookup_bond_entry(bond, flow, vlan)->tx_bytes += n_bytes;
668 static struct bond_slave *
669 bond_slave_from_bal_node(struct list *bal)
671 return CONTAINER_OF(bal, struct bond_slave, bal_node);
675 log_bals(struct bond *bond, const struct list *bals)
677 if (VLOG_IS_DBG_ENABLED()) {
678 struct ds ds = DS_EMPTY_INITIALIZER;
679 const struct bond_slave *slave;
681 LIST_FOR_EACH (slave, bal_node, bals) {
683 ds_put_char(&ds, ',');
685 ds_put_format(&ds, " %s %"PRIu64"kB",
686 slave->name, slave->tx_bytes / 1024);
688 if (!slave->enabled) {
689 ds_put_cstr(&ds, " (disabled)");
691 if (!list_is_empty(&slave->entries)) {
692 struct bond_entry *e;
694 ds_put_cstr(&ds, " (");
695 LIST_FOR_EACH (e, list_node, &slave->entries) {
696 if (&e->list_node != list_front(&slave->entries)) {
697 ds_put_cstr(&ds, " + ");
699 ds_put_format(&ds, "h%td: %"PRIu64"kB",
700 e - bond->hash, e->tx_bytes / 1024);
702 ds_put_cstr(&ds, ")");
705 VLOG_DBG("bond %s:%s", bond->name, ds_cstr(&ds));
710 /* Shifts 'hash' from its current slave to 'to'. */
712 bond_shift_load(struct bond_entry *hash, struct bond_slave *to,
715 struct bond_slave *from = hash->slave;
716 struct bond *bond = from->bond;
717 uint64_t delta = hash->tx_bytes;
719 VLOG_INFO("bond %s: shift %"PRIu64"kB of load (with hash %td) "
720 "from %s to %s (now carrying %"PRIu64"kB and "
721 "%"PRIu64"kB load, respectively)",
722 bond->name, delta / 1024, hash - bond->hash,
723 from->name, to->name,
724 (from->tx_bytes - delta) / 1024,
725 (to->tx_bytes + delta) / 1024);
727 /* Shift load away from 'from' to 'to'. */
728 from->tx_bytes -= delta;
729 to->tx_bytes += delta;
731 /* Arrange for flows to be revalidated. */
732 tag_set_add(set, hash->tag);
734 hash->tag = tag_create_random();
737 /* Pick and returns a bond_entry to migrate to 'to' (the least-loaded slave),
738 * given that doing so must decrease the ratio of the load on the two slaves by
739 * at least 0.1. Returns NULL if there is no appropriate entry.
741 * The list of entries isn't sorted. I don't know of a reason to prefer to
742 * shift away small hashes or large hashes. */
743 static struct bond_entry *
744 choose_entry_to_migrate(const struct bond_slave *from, uint64_t to_tx_bytes)
746 struct bond_entry *e;
748 if (list_is_short(&from->entries)) {
749 /* 'from' carries no more than one MAC hash, so shifting load away from
750 * it would be pointless. */
754 LIST_FOR_EACH (e, list_node, &from->entries) {
755 double old_ratio, new_ratio;
758 if (to_tx_bytes == 0) {
759 /* Nothing on the new slave, move it. */
764 old_ratio = (double)from->tx_bytes / to_tx_bytes;
765 new_ratio = (double)(from->tx_bytes - delta) / (to_tx_bytes + delta);
766 if (old_ratio - new_ratio > 0.1) {
767 /* Would decrease the ratio, move it. */
775 /* Inserts 'slave' into 'bals' so that descending order of 'tx_bytes' is
778 insert_bal(struct list *bals, struct bond_slave *slave)
780 struct bond_slave *pos;
782 LIST_FOR_EACH (pos, bal_node, bals) {
783 if (slave->tx_bytes > pos->tx_bytes) {
787 list_insert(&pos->bal_node, &slave->bal_node);
790 /* Removes 'slave' from its current list and then inserts it into 'bals' so
791 * that descending order of 'tx_bytes' is maintained. */
793 reinsert_bal(struct list *bals, struct bond_slave *slave)
795 list_remove(&slave->bal_node);
796 insert_bal(bals, slave);
799 /* If 'bond' needs rebalancing, does so.
801 * The caller should have called bond_account() for each active flow, to ensure
802 * that flow data is consistently accounted at this point. */
804 bond_rebalance(struct bond *bond, struct tag_set *tags)
806 struct bond_slave *slave;
807 struct bond_entry *e;
810 if (!bond_is_balanced(bond) || time_msec() < bond->next_rebalance) {
813 bond->next_rebalance = time_msec() + bond->rebalance_interval;
815 /* Add each bond_entry to its slave's 'entries' list.
816 * Compute each slave's tx_bytes as the sum of its entries' tx_bytes. */
817 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
819 list_init(&slave->entries);
821 for (e = &bond->hash[0]; e <= &bond->hash[BOND_MASK]; e++) {
822 if (e->slave && e->tx_bytes) {
823 e->slave->tx_bytes += e->tx_bytes;
824 list_push_back(&e->slave->entries, &e->list_node);
828 /* Add enabled slaves to 'bals' in descending order of tx_bytes.
830 * XXX This is O(n**2) in the number of slaves but it could be O(n lg n)
831 * with a proper list sort algorithm. */
833 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
834 if (slave->enabled) {
835 insert_bal(&bals, slave);
838 log_bals(bond, &bals);
840 /* Shift load from the most-loaded slaves to the least-loaded slaves. */
841 while (!list_is_short(&bals)) {
842 struct bond_slave *from = bond_slave_from_bal_node(list_front(&bals));
843 struct bond_slave *to = bond_slave_from_bal_node(list_back(&bals));
846 overload = from->tx_bytes - to->tx_bytes;
847 if (overload < to->tx_bytes >> 5 || overload < 100000) {
848 /* The extra load on 'from' (and all less-loaded slaves), compared
849 * to that of 'to' (the least-loaded slave), is less than ~3%, or
850 * it is less than ~1Mbps. No point in rebalancing. */
854 /* 'from' is carrying significantly more load than 'to', and that load
855 * is split across at least two different hashes. */
856 e = choose_entry_to_migrate(from, to->tx_bytes);
858 bond_shift_load(e, to, tags);
860 /* Delete element from from->entries.
862 * We don't add the element to to->hashes. That would only allow
863 * 'e' to be migrated to another slave in this rebalancing run, and
864 * there is no point in doing that. */
865 list_remove(&e->list_node);
867 /* Re-sort 'bals'. */
868 reinsert_bal(&bals, from);
869 reinsert_bal(&bals, to);
871 /* Can't usefully migrate anything away from 'from'.
872 * Don't reconsider it. */
873 list_remove(&from->bal_node);
877 /* Implement exponentially weighted moving average. A weight of 1/2 causes
878 * historical data to decay to <1% in 7 rebalancing runs. 1,000,000 bytes
879 * take 20 rebalancing runs to decay to 0 and get deleted entirely. */
880 for (e = &bond->hash[0]; e <= &bond->hash[BOND_MASK]; e++) {
888 /* Bonding unixctl user interface functions. */
891 bond_find(const char *name)
895 HMAP_FOR_EACH_WITH_HASH (bond, hmap_node, hash_string(name, 0),
897 if (!strcmp(bond->name, name)) {
904 static struct bond_slave *
905 bond_lookup_slave(struct bond *bond, const char *slave_name)
907 struct bond_slave *slave;
909 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
910 if (!strcmp(slave->name, slave_name)) {
918 bond_unixctl_list(struct unixctl_conn *conn,
919 const char *args OVS_UNUSED, void *aux OVS_UNUSED)
921 struct ds ds = DS_EMPTY_INITIALIZER;
922 const struct bond *bond;
924 ds_put_cstr(&ds, "bond\ttype\tslaves\n");
926 HMAP_FOR_EACH (bond, hmap_node, &all_bonds) {
927 const struct bond_slave *slave;
930 ds_put_format(&ds, "%s\t%s\t",
931 bond->name, bond_mode_to_string(bond->balance));
934 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
936 ds_put_cstr(&ds, ", ");
938 ds_put_cstr(&ds, slave->name);
940 ds_put_char(&ds, '\n');
942 unixctl_command_reply(conn, 200, ds_cstr(&ds));
947 bond_unixctl_show(struct unixctl_conn *conn,
948 const char *args, void *aux OVS_UNUSED)
950 struct ds ds = DS_EMPTY_INITIALIZER;
951 const struct bond_slave *slave;
952 const struct bond *bond;
954 bond = bond_find(args);
956 unixctl_command_reply(conn, 501, "no such bond");
960 ds_put_format(&ds, "bond_mode: %s\n",
961 bond_mode_to_string(bond->balance));
964 ds_put_format(&ds, "lacp: %s\n",
965 lacp_is_active(bond->lacp) ? "active" : "passive");
967 ds_put_cstr(&ds, "lacp: off\n");
970 if (bond->balance != BM_AB) {
971 ds_put_format(&ds, "bond-hash-algorithm: %s\n",
972 bond_is_tcp_hash(bond) ? "balance-tcp" : "balance-slb");
975 ds_put_format(&ds, "bond-detect-mode: %s\n",
976 bond->monitor ? "carrier" : "miimon");
978 if (!bond->monitor) {
979 ds_put_format(&ds, "bond-miimon-interval: %lld\n",
980 bond->miimon_interval);
983 ds_put_format(&ds, "updelay: %d ms\n", bond->updelay);
984 ds_put_format(&ds, "downdelay: %d ms\n", bond->downdelay);
986 if (bond_is_balanced(bond)) {
987 ds_put_format(&ds, "next rebalance: %lld ms\n",
988 bond->next_rebalance - time_msec());
991 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
992 struct bond_entry *be;
996 ds_put_format(&ds, "\nslave %s: %s\n",
997 slave->name, slave->enabled ? "enabled" : "disabled");
998 if (slave == bond->active_slave) {
999 ds_put_cstr(&ds, "\tactive slave\n");
1001 if (slave->delay_expires != LLONG_MAX) {
1002 ds_put_format(&ds, "\t%s expires in %lld ms\n",
1003 slave->enabled ? "downdelay" : "updelay",
1004 slave->delay_expires - time_msec());
1007 if (!bond_is_balanced(bond)) {
1012 memset(&flow, 0, sizeof flow);
1013 for (be = bond->hash; be <= &bond->hash[BOND_MASK]; be++) {
1014 int hash = be - bond->hash;
1016 if (be->slave != slave) {
1020 ds_put_format(&ds, "\thash %d: %"PRIu64" kB load\n",
1021 hash, be->tx_bytes / 1024);
1023 if (bond->balance != BM_SLB) {
1027 /* XXX How can we list the MACs assigned to hashes? */
1030 unixctl_command_reply(conn, 200, ds_cstr(&ds));
1035 bond_unixctl_migrate(struct unixctl_conn *conn, const char *args_,
1036 void *aux OVS_UNUSED)
1038 char *args = (char *) args_;
1039 char *save_ptr = NULL;
1040 char *bond_s, *hash_s, *slave_s;
1042 struct bond_slave *slave;
1043 struct bond_entry *entry;
1046 bond_s = strtok_r(args, " ", &save_ptr);
1047 hash_s = strtok_r(NULL, " ", &save_ptr);
1048 slave_s = strtok_r(NULL, " ", &save_ptr);
1050 unixctl_command_reply(conn, 501,
1051 "usage: bond/migrate BOND HASH SLAVE");
1055 bond = bond_find(bond_s);
1057 unixctl_command_reply(conn, 501, "no such bond");
1061 if (bond->balance != BM_SLB) {
1062 unixctl_command_reply(conn, 501, "not an SLB bond");
1066 if (strspn(hash_s, "0123456789") == strlen(hash_s)) {
1067 hash = atoi(hash_s) & BOND_MASK;
1069 unixctl_command_reply(conn, 501, "bad hash");
1073 slave = bond_lookup_slave(bond, slave_s);
1075 unixctl_command_reply(conn, 501, "no such slave");
1079 if (!slave->enabled) {
1080 unixctl_command_reply(conn, 501, "cannot migrate to disabled slave");
1084 entry = &bond->hash[hash];
1085 tag_set_add(&bond->unixctl_tags, entry->tag);
1086 entry->slave = slave;
1087 entry->tag = tag_create_random();
1088 unixctl_command_reply(conn, 200, "migrated");
1092 bond_unixctl_set_active_slave(struct unixctl_conn *conn, const char *args_,
1093 void *aux OVS_UNUSED)
1095 char *args = (char *) args_;
1096 char *save_ptr = NULL;
1097 char *bond_s, *slave_s;
1099 struct bond_slave *slave;
1101 bond_s = strtok_r(args, " ", &save_ptr);
1102 slave_s = strtok_r(NULL, " ", &save_ptr);
1104 unixctl_command_reply(conn, 501,
1105 "usage: bond/set-active-slave BOND SLAVE");
1109 bond = bond_find(bond_s);
1111 unixctl_command_reply(conn, 501, "no such bond");
1115 slave = bond_lookup_slave(bond, slave_s);
1117 unixctl_command_reply(conn, 501, "no such slave");
1121 if (!slave->enabled) {
1122 unixctl_command_reply(conn, 501, "cannot make disabled slave active");
1126 if (bond->active_slave != slave) {
1127 tag_set_add(&bond->unixctl_tags, bond_get_active_slave_tag(bond));
1128 bond->active_slave = slave;
1129 bond->active_slave->tag = tag_create_random();
1130 VLOG_INFO("bond %s: active interface is now %s",
1131 bond->name, slave->name);
1132 bond->send_learning_packets = true;
1133 unixctl_command_reply(conn, 200, "done");
1135 unixctl_command_reply(conn, 200, "no change");
1140 enable_slave(struct unixctl_conn *conn, const char *args_, bool enable)
1142 char *args = (char *) args_;
1143 char *save_ptr = NULL;
1144 char *bond_s, *slave_s;
1146 struct bond_slave *slave;
1148 bond_s = strtok_r(args, " ", &save_ptr);
1149 slave_s = strtok_r(NULL, " ", &save_ptr);
1151 char *usage = xasprintf("usage: bond/%s-slave BOND SLAVE",
1152 enable ? "enable" : "disable");
1153 unixctl_command_reply(conn, 501, usage);
1158 bond = bond_find(bond_s);
1160 unixctl_command_reply(conn, 501, "no such bond");
1164 slave = bond_lookup_slave(bond, slave_s);
1166 unixctl_command_reply(conn, 501, "no such slave");
1170 bond_enable_slave(slave, enable, &bond->unixctl_tags);
1171 unixctl_command_reply(conn, 501, enable ? "enabled" : "disabled");
1175 bond_unixctl_enable_slave(struct unixctl_conn *conn, const char *args,
1176 void *aux OVS_UNUSED)
1178 enable_slave(conn, args, true);
1182 bond_unixctl_disable_slave(struct unixctl_conn *conn, const char *args,
1183 void *aux OVS_UNUSED)
1185 enable_slave(conn, args, false);
1189 bond_unixctl_hash(struct unixctl_conn *conn, const char *args_,
1190 void *aux OVS_UNUSED)
1192 char *args = (char *) args_;
1193 uint8_t mac[ETH_ADDR_LEN];
1197 char *mac_s, *vlan_s;
1198 char *save_ptr = NULL;
1200 mac_s = strtok_r(args, " ", &save_ptr);
1201 vlan_s = strtok_r(NULL, " ", &save_ptr);
1204 if (sscanf(vlan_s, "%u", &vlan) != 1) {
1205 unixctl_command_reply(conn, 501, "invalid vlan");
1209 vlan = OFP_VLAN_NONE;
1212 if (sscanf(mac_s, ETH_ADDR_SCAN_FMT, ETH_ADDR_SCAN_ARGS(mac))
1213 == ETH_ADDR_SCAN_COUNT) {
1214 hash = bond_hash_src(mac, vlan) & BOND_MASK;
1216 hash_cstr = xasprintf("%u", hash);
1217 unixctl_command_reply(conn, 200, hash_cstr);
1220 unixctl_command_reply(conn, 501, "invalid mac");
1227 unixctl_command_register("bond/list", bond_unixctl_list, NULL);
1228 unixctl_command_register("bond/show", bond_unixctl_show, NULL);
1229 unixctl_command_register("bond/migrate", bond_unixctl_migrate, NULL);
1230 unixctl_command_register("bond/set-active-slave",
1231 bond_unixctl_set_active_slave, NULL);
1232 unixctl_command_register("bond/enable-slave", bond_unixctl_enable_slave,
1234 unixctl_command_register("bond/disable-slave", bond_unixctl_disable_slave,
1236 unixctl_command_register("bond/hash", bond_unixctl_hash, NULL);
1240 bond_entry_reset(struct bond *bond)
1242 if (bond->balance != BM_AB) {
1243 size_t hash_len = (BOND_MASK + 1) * sizeof *bond->hash;
1246 bond->hash = xmalloc(hash_len);
1248 memset(bond->hash, 0, hash_len);
1250 bond->next_rebalance = time_msec() + bond->rebalance_interval;
1257 static struct bond_slave *
1258 bond_slave_lookup(struct bond *bond, const void *slave_)
1260 struct bond_slave *slave;
1262 HMAP_FOR_EACH_IN_BUCKET (slave, hmap_node, hash_pointer(slave_, 0),
1264 if (slave->aux == slave_) {
1273 bond_is_link_up(struct bond *bond, struct netdev *netdev)
1275 return (bond->detect == BLSM_CARRIER
1276 ? netdev_get_carrier(netdev)
1277 : netdev_get_miimon(netdev));
1281 bond_stb_sort_cmp__(const void *a_, const void *b_)
1283 const struct bond_slave *const *ap = a_;
1284 const struct bond_slave *const *bp = b_;
1285 const struct bond_slave *a = *ap;
1286 const struct bond_slave *b = *bp;
1287 uint16_t aid = a->stb_id;
1288 uint16_t bid = b->stb_id;
1290 return aid < bid ? -1 : aid > bid;
1294 bond_stb_sort(struct bond *bond)
1298 if (!bond->stb_slaves || !bond->stb_need_sort) {
1301 bond->stb_need_sort = false;
1303 qsort(bond->stb_slaves, bond->n_stb_slaves, sizeof *bond->stb_slaves,
1304 bond_stb_sort_cmp__);
1306 for (i = 0; i < bond->n_stb_slaves; i++) {
1307 bond->stb_slaves[i]->stb_idx = i;
1314 bond_stb_enable_slave(struct bond_slave *slave)
1316 struct bond *bond = slave->bond;
1318 if (!bond->stb_slaves) {
1322 bond->stb_need_sort = true;
1324 if (slave->enabled) {
1325 if (bond->len_stb_slaves <= bond->n_stb_slaves) {
1326 bond->stb_slaves = x2nrealloc(bond->stb_slaves,
1327 &bond->len_stb_slaves,
1328 sizeof *bond->stb_slaves);
1331 slave->stb_idx = bond->n_stb_slaves++;
1332 bond->stb_slaves[slave->stb_idx] = slave;
1334 size_t index = slave->stb_idx;
1335 bond->stb_slaves[index] = bond->stb_slaves[--bond->n_stb_slaves];
1336 bond->stb_slaves[index]->stb_idx = index;
1341 bond_enable_slave(struct bond_slave *slave, bool enable, struct tag_set *tags)
1343 slave->delay_expires = LLONG_MAX;
1344 if (enable != slave->enabled) {
1345 slave->enabled = enable;
1346 if (!slave->enabled) {
1347 VLOG_WARN("interface %s: disabled", slave->name);
1349 tag_set_add(tags, slave->tag);
1352 VLOG_WARN("interface %s: enabled", slave->name);
1353 slave->tag = tag_create_random();
1355 bond_stb_enable_slave(slave);
1360 bond_link_status_update(struct bond_slave *slave, struct tag_set *tags)
1362 struct bond *bond = slave->bond;
1365 up = slave->up && lacp_slave_may_enable(bond->lacp, slave->aux);
1366 if ((up == slave->enabled) != (slave->delay_expires == LLONG_MAX)) {
1367 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
1368 VLOG_INFO_RL(&rl, "interface %s: link state %s",
1369 slave->name, up ? "up" : "down");
1370 if (up == slave->enabled) {
1371 slave->delay_expires = LLONG_MAX;
1372 VLOG_INFO_RL(&rl, "interface %s: will not be %s",
1373 slave->name, up ? "disabled" : "enabled");
1375 int delay = (lacp_negotiated(bond->lacp) ? 0
1376 : up ? bond->updelay : bond->downdelay);
1377 slave->delay_expires = time_msec() + delay;
1379 VLOG_INFO_RL(&rl, "interface %s: will be %s if it stays %s "
1382 up ? "enabled" : "disabled",
1389 if (time_msec() >= slave->delay_expires) {
1390 bond_enable_slave(slave, up, tags);
1395 bond_is_tcp_hash(const struct bond *bond)
1397 return (bond->balance == BM_TCP || bond->balance == BM_STABLE)
1398 && lacp_negotiated(bond->lacp);
1402 bond_hash_src(const uint8_t mac[ETH_ADDR_LEN], uint16_t vlan)
1404 return hash_bytes(mac, ETH_ADDR_LEN, vlan);
1408 bond_hash_tcp(const struct flow *flow, uint16_t vlan)
1410 struct flow hash_flow = *flow;
1411 hash_flow.vlan_tci = vlan;
1413 /* The symmetric quality of this hash function is not required, but
1414 * flow_hash_symmetric_l4 already exists, and is sufficient for our
1415 * purposes, so we use it out of convenience. */
1416 return flow_hash_symmetric_l4(&hash_flow, 0);
1420 bond_hash(const struct bond *bond, const struct flow *flow, uint16_t vlan)
1422 assert(bond->balance != BM_AB);
1424 return (bond_is_tcp_hash(bond)
1425 ? bond_hash_tcp(flow, vlan)
1426 : bond_hash_src(flow->dl_src, vlan));
1429 static struct bond_entry *
1430 lookup_bond_entry(const struct bond *bond, const struct flow *flow,
1433 return &bond->hash[bond_hash(bond, flow, vlan) & BOND_MASK];
1436 static struct bond_slave *
1437 choose_output_slave(const struct bond *bond, const struct flow *flow,
1440 struct bond_entry *e;
1442 switch (bond->balance) {
1444 return bond->active_slave;
1447 if (bond->n_stb_slaves) {
1448 return bond->stb_slaves[bond_hash(bond, flow, vlan)
1449 % bond->n_stb_slaves];
1451 return bond->active_slave;
1456 e = lookup_bond_entry(bond, flow, vlan);
1457 if (!e->slave || !e->slave->enabled) {
1458 e->slave = CONTAINER_OF(hmap_random_node(&bond->slaves),
1459 struct bond_slave, hmap_node);
1460 if (!e->slave->enabled) {
1461 e->slave = bond->active_slave;
1463 e->tag = tag_create_random();
1472 static struct bond_slave *
1473 bond_choose_slave(const struct bond *bond)
1475 struct bond_slave *slave, *best;
1477 /* Find an enabled slave. */
1478 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
1479 if (slave->enabled) {
1484 /* All interfaces are disabled. Find an interface that will be enabled
1485 * after its updelay expires. */
1487 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
1488 if (slave->delay_expires != LLONG_MAX
1489 && lacp_slave_may_enable(bond->lacp, slave->aux)
1490 && (!best || slave->delay_expires < best->delay_expires)) {
1498 bond_choose_active_slave(struct bond *bond, struct tag_set *tags)
1500 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
1501 struct bond_slave *old_active_slave = bond->active_slave;
1503 bond->active_slave = bond_choose_slave(bond);
1504 if (bond->active_slave) {
1505 if (bond->active_slave->enabled) {
1506 VLOG_INFO_RL(&rl, "bond %s: active interface is now %s",
1507 bond->name, bond->active_slave->name);
1509 VLOG_INFO_RL(&rl, "bond %s: active interface is now %s, skipping "
1510 "remaining %lld ms updelay (since no interface was "
1511 "enabled)", bond->name, bond->active_slave->name,
1512 bond->active_slave->delay_expires - time_msec());
1513 bond_enable_slave(bond->active_slave, true, tags);
1516 if (!old_active_slave) {
1517 tag_set_add(tags, bond->no_slaves_tag);
1520 bond->send_learning_packets = true;
1521 } else if (old_active_slave) {
1522 VLOG_WARN_RL(&rl, "bond %s: all interfaces disabled", bond->name);
1526 /* Returns the tag for 'bond''s active slave, or 'bond''s no_slaves_tag if
1527 * there is no active slave. */
1529 bond_get_active_slave_tag(const struct bond *bond)
1531 return (bond->active_slave
1532 ? bond->active_slave->tag
1533 : bond->no_slaves_tag);
1536 /* Attempts to make the sum of the bond slaves' statistics appear on the fake
1537 * bond interface. */
1539 bond_update_fake_slave_stats(struct bond *bond)
1541 struct netdev_stats bond_stats;
1542 struct bond_slave *slave;
1543 struct netdev *bond_dev;
1545 memset(&bond_stats, 0, sizeof bond_stats);
1547 HMAP_FOR_EACH (slave, hmap_node, &bond->slaves) {
1548 struct netdev_stats slave_stats;
1550 if (!netdev_get_stats(slave->netdev, &slave_stats)) {
1551 /* XXX: We swap the stats here because they are swapped back when
1552 * reported by the internal device. The reason for this is
1553 * internal devices normally represent packets going into the
1554 * system but when used as fake bond device they represent packets
1555 * leaving the system. We really should do this in the internal
1556 * device itself because changing it here reverses the counts from
1557 * the perspective of the switch. However, the internal device
1558 * doesn't know what type of device it represents so we have to do
1559 * it here for now. */
1560 bond_stats.tx_packets += slave_stats.rx_packets;
1561 bond_stats.tx_bytes += slave_stats.rx_bytes;
1562 bond_stats.rx_packets += slave_stats.tx_packets;
1563 bond_stats.rx_bytes += slave_stats.tx_bytes;
1567 if (!netdev_open_default(bond->name, &bond_dev)) {
1568 netdev_set_stats(bond_dev, &bond_stats);
1569 netdev_close(bond_dev);