uint16_t out_port;
/* Learn the source MAC. */
- if (sw->ml) {
- if (mac_learning_learn(sw->ml, flow->dl_src, 0, flow->in_port,
- GRAT_ARP_LOCK_NONE)) {
+ if (mac_learning_may_learn(sw->ml, flow->dl_src, 0)) {
+ struct mac_entry *mac = mac_learning_insert(sw->ml, flow->dl_src, 0);
+ if (mac_entry_is_new(mac) || mac->port != flow->in_port) {
VLOG_DBG_RL(&rl, "%016llx: learned that "ETH_ADDR_FMT" is on "
"port %"PRIu16, sw->datapath_id,
ETH_ADDR_ARGS(flow->dl_src), flow->in_port);
+
+ mac->port = flow->in_port;
+ mac_learning_changed(sw->ml, mac);
}
}
out_port = OFPP_FLOOD;
if (sw->ml) {
- int learned_port = mac_learning_lookup(sw->ml, flow->dl_dst, 0, NULL);
- if (learned_port >= 0) {
- out_port = learned_port;
+ struct mac_entry *mac;
+
+ mac = mac_learning_lookup(sw->ml, flow->dl_dst, 0, NULL);
+ if (mac) {
+ out_port = mac->port;
if (out_port == flow->in_port) {
/* Don't send a packet back out its input port. */
return OFPP_NONE;
/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
return !(ml->flood_vlans && bitmap_is_set(ml->flood_vlans, vlan));
}
-/* Attempts to make 'ml' learn from the fact that a frame from 'src_mac' was
- * just observed arriving from 'src_port' on the given 'vlan'.
- *
- * Returns nonzero if we actually learned something from this, zero if it just
- * confirms what we already knew. The nonzero return value is the tag of flows
- * that now need revalidation.
- *
- * The 'vlan' parameter is used to maintain separate per-VLAN learning tables.
- * Specify 0 if this behavior is undesirable.
+/* Returns true if 'src_mac' may be learned on 'vlan' for 'ml'.
+ * Returns false if 'ml' is NULL, if src_mac is not valid for learning, or if
+ * 'vlan' is configured on 'ml' to flood all packets. */
+bool
+mac_learning_may_learn(const struct mac_learning *ml,
+ const uint8_t src_mac[ETH_ADDR_LEN], uint16_t vlan)
+{
+ return ml && is_learning_vlan(ml, vlan) && !eth_addr_is_multicast(src_mac);
+}
+
+/* Searches 'ml' for and returns a MAC learning entry for 'src_mac' in 'vlan',
+ * inserting a new entry if necessary. The caller must have already verified,
+ * by calling mac_learning_may_learn(), that 'src_mac' and 'vlan' are
+ * learnable.
*
- * 'lock_type' specifies whether the entry should be locked or existing locks
- * are check. */
-tag_type
-mac_learning_learn(struct mac_learning *ml,
- const uint8_t src_mac[ETH_ADDR_LEN], uint16_t vlan,
- uint16_t src_port, enum grat_arp_lock_type lock_type)
+ * If the returned MAC entry is new (as may be determined by calling
+ * mac_entry_is_new()), then the caller must pass the new entry to
+ * mac_learning_changed(). The caller must also initialize the new entry's
+ * 'port' member. Otherwise calling those functions is at the caller's
+ * discretion. */
+struct mac_entry *
+mac_learning_insert(struct mac_learning *ml,
+ const uint8_t src_mac[ETH_ADDR_LEN], uint16_t vlan)
{
struct mac_entry *e;
struct list *bucket;
- if (!is_learning_vlan(ml, vlan)) {
- return 0;
- }
-
- if (eth_addr_is_multicast(src_mac)) {
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30, 30);
- VLOG_DBG_RL(&rl, "multicast packet source "ETH_ADDR_FMT,
- ETH_ADDR_ARGS(src_mac));
- return 0;
- }
-
bucket = mac_table_bucket(ml, src_mac, vlan);
e = search_bucket(bucket, src_mac, vlan);
if (!e) {
e = mac_entry_from_lru_node(ml->lrus.next);
list_remove(&e->hash_node);
}
- memcpy(e->mac, src_mac, ETH_ADDR_LEN);
list_push_front(bucket, &e->hash_node);
- e->port = -1;
+ memcpy(e->mac, src_mac, ETH_ADDR_LEN);
e->vlan = vlan;
- e->tag = make_unknown_mac_tag(ml, src_mac, vlan);
+ e->tag = 0;
e->grat_arp_lock = TIME_MIN;
}
- if (lock_type != GRAT_ARP_LOCK_CHECK || time_now() >= e->grat_arp_lock) {
- /* Make the entry most-recently-used. */
- list_remove(&e->lru_node);
- list_push_back(&ml->lrus, &e->lru_node);
- e->expires = time_now() + MAC_ENTRY_IDLE_TIME;
- if (lock_type == GRAT_ARP_LOCK_SET) {
- e->grat_arp_lock = time_now() + MAC_GRAT_ARP_LOCK_TIME;
- }
-
- /* Did we learn something? */
- if (e->port != src_port) {
- tag_type old_tag = e->tag;
- e->port = src_port;
- e->tag = tag_create_random();
- COVERAGE_INC(mac_learning_learned);
- return old_tag;
- }
- }
+ /* Mark 'e' as recently used. */
+ list_remove(&e->lru_node);
+ list_push_back(&ml->lrus, &e->lru_node);
+ e->expires = time_now() + MAC_ENTRY_IDLE_TIME;
- return 0;
+ return e;
}
-/* Looks up MAC 'dst' for VLAN 'vlan' in 'ml'. Returns the port on which a
- * frame destined for 'dst' should be sent, -1 if unknown. 'is_grat_arp_locked'
- * is an optional parameter that returns whether the entry is currently
- * locked. */
-int
-mac_learning_lookup(const struct mac_learning *ml,
- const uint8_t dst[ETH_ADDR_LEN], uint16_t vlan,
- bool *is_grat_arp_locked)
+/* Changes 'e''s tag to a new, randomly selected one, and returns the tag that
+ * would have been previously used for this entry's MAC and VLAN (either before
+ * 'e' was inserted, if it is new, or otherwise before its port was updated.)
+ *
+ * The client should call this function after obtaining a MAC learning entry
+ * from mac_learning_insert(), if the entry is either new or if its learned
+ * port has changed. */
+tag_type
+mac_learning_changed(struct mac_learning *ml, struct mac_entry *e)
{
- tag_type tag = 0;
- return mac_learning_lookup_tag(ml, dst, vlan, &tag, is_grat_arp_locked);
+ tag_type old_tag = e->tag;
+
+ COVERAGE_INC(mac_learning_learned);
+
+ e->tag = tag_create_random();
+ return old_tag ? old_tag : make_unknown_mac_tag(ml, e->mac, e->vlan);
}
-/* Looks up MAC 'dst' for VLAN 'vlan' in 'ml'. Returns the port on which a
- * frame destined for 'dst' should be sent, -1 if unknown.
- *
- * Adds to '*tag' (which the caller must have initialized) the tag that should
- * be attached to any flow created based on the return value, if any, to allow
- * those flows to be revalidated when the MAC learning entry changes.
- *
- * 'is_grat_arp_locked' is an optional parameter that returns whether the entry
- * is currently locked.*/
-int
-mac_learning_lookup_tag(const struct mac_learning *ml,
- const uint8_t dst[ETH_ADDR_LEN], uint16_t vlan,
- tag_type *tag, bool *is_grat_arp_locked)
+/* Looks up MAC 'dst' for VLAN 'vlan' in 'ml' and returns the associated MAC
+ * learning entry, if any. If 'tag' is nonnull, then the tag that associates
+ * 'dst' and 'vlan' with its currently learned port will be OR'd into
+ * '*tag'. */
+struct mac_entry *
+mac_learning_lookup(const struct mac_learning *ml,
+ const uint8_t dst[ETH_ADDR_LEN], uint16_t vlan,
+ tag_type *tag)
{
- if (eth_addr_is_multicast(dst) || !is_learning_vlan(ml, vlan)) {
- return -1;
+ if (eth_addr_is_multicast(dst)) {
+ /* No tag because the treatment of multicast destinations never
+ * changes. */
+ return NULL;
+ } else if (!is_learning_vlan(ml, vlan)) {
+ /* We don't tag this property. The set of learning VLANs changes so
+ * rarely that we revalidate every flow when it changes. */
+ return NULL;
} else {
struct mac_entry *e = search_bucket(mac_table_bucket(ml, dst, vlan),
dst, vlan);
- if (e) {
- *tag |= e->tag;
-
- if (is_grat_arp_locked) {
- *is_grat_arp_locked = time_now() < e->grat_arp_lock;
- }
-
- return e->port;
- } else {
- *tag |= make_unknown_mac_tag(ml, dst, vlan);
- return -1;
+ assert(e == NULL || e->tag != 0);
+ if (tag) {
+ /* Tag either the learned port or the lack thereof. */
+ *tag |= e ? e->tag : make_unknown_mac_tag(ml, dst, vlan);
}
+ return e;
}
}
/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include "list.h"
#include "packets.h"
#include "tag.h"
+#include "timeval.h"
#define MAC_HASH_BITS 10
#define MAC_HASH_MASK (MAC_HASH_SIZE - 1)
* relearning based on a reflection from a bond slave. */
#define MAC_GRAT_ARP_LOCK_TIME 5
-enum grat_arp_lock_type {
- GRAT_ARP_LOCK_NONE,
- GRAT_ARP_LOCK_SET,
- GRAT_ARP_LOCK_CHECK
-};
-
/* A MAC learning table entry. */
struct mac_entry {
struct list hash_node; /* Element in a mac_learning 'table' list. */
int mac_entry_age(const struct mac_entry *);
+/* Returns true if mac_learning_insert() just created 'mac' and the caller has
+ * not yet properly initialized it. */
+static inline bool mac_entry_is_new(const struct mac_entry *mac)
+{
+ return !mac->tag;
+}
+
+/* Sets a gratuitous ARP lock on 'mac' that will expire in
+ * MAC_GRAT_ARP_LOCK_TIME seconds. */
+static inline void mac_entry_set_grat_arp_lock(struct mac_entry *mac)
+{
+ mac->grat_arp_lock = time_now() + MAC_GRAT_ARP_LOCK_TIME;
+}
+
+/* Returns true if a gratuitous ARP lock is in effect on 'mac', false if none
+ * has ever been asserted or if it has expired. */
+static inline bool mac_entry_is_grat_arp_locked(const struct mac_entry *mac)
+{
+ return time_now() >= mac->grat_arp_lock;
+}
+
/* MAC learning table. */
struct mac_learning {
struct list free; /* Not-in-use entries. */
unsigned long *flood_vlans; /* Bitmap of learning disabled VLANs. */
};
+/* Basics. */
struct mac_learning *mac_learning_create(void);
void mac_learning_destroy(struct mac_learning *);
+
+void mac_learning_run(struct mac_learning *, struct tag_set *);
+void mac_learning_wait(struct mac_learning *);
+
+/* Configuration. */
bool mac_learning_set_flood_vlans(struct mac_learning *,
unsigned long *bitmap);
-tag_type mac_learning_learn(struct mac_learning *,
- const uint8_t src[ETH_ADDR_LEN], uint16_t vlan,
- uint16_t src_port, enum grat_arp_lock_type
- lock_type);
-int mac_learning_lookup(const struct mac_learning *,
- const uint8_t dst[ETH_ADDR_LEN], uint16_t vlan,
- bool *is_grat_arp_locked);
-int mac_learning_lookup_tag(const struct mac_learning *,
- const uint8_t dst[ETH_ADDR_LEN],
- uint16_t vlan, tag_type *tag,
- bool *is_grat_arp_locked);
+
+/* Learning. */
+bool mac_learning_may_learn(const struct mac_learning *,
+ const uint8_t src_mac[ETH_ADDR_LEN],
+ uint16_t vlan);
+struct mac_entry *mac_learning_insert(struct mac_learning *,
+ const uint8_t src[ETH_ADDR_LEN],
+ uint16_t vlan);
+tag_type mac_learning_changed(struct mac_learning *, struct mac_entry *);
+
+/* Lookup. */
+struct mac_entry *mac_learning_lookup(const struct mac_learning *,
+ const uint8_t dst[ETH_ADDR_LEN],
+ uint16_t vlan, tag_type *);
+
+/* Flushing. */
void mac_learning_flush(struct mac_learning *);
-void mac_learning_run(struct mac_learning *, struct tag_set *);
-void mac_learning_wait(struct mac_learning *);
#endif /* mac-learning.h */
uint16_t *nf_output_iface, void *ofproto_)
{
struct ofproto *ofproto = ofproto_;
- int out_port;
+ struct mac_entry *dst_mac;
/* Drop frames for reserved multicast addresses. */
if (eth_addr_is_reserved(flow->dl_dst)) {
}
/* Learn source MAC (but don't try to learn from revalidation). */
- if (packet != NULL) {
- tag_type rev_tag = mac_learning_learn(ofproto->ml, flow->dl_src,
- 0, flow->in_port,
- GRAT_ARP_LOCK_NONE);
- if (rev_tag) {
+ if (packet != NULL
+ && mac_learning_may_learn(ofproto->ml, flow->dl_src, 0)) {
+ struct mac_entry *src_mac;
+
+ src_mac = mac_learning_insert(ofproto->ml, flow->dl_src, 0);
+ if (mac_entry_is_new(src_mac) || src_mac->port != flow->in_port) {
/* The log messages here could actually be useful in debugging,
* so keep the rate limit relatively high. */
static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30, 300);
VLOG_DBG_RL(&rl, "learned that "ETH_ADDR_FMT" is on port %"PRIu16,
ETH_ADDR_ARGS(flow->dl_src), flow->in_port);
- ofproto_revalidate(ofproto, rev_tag);
+
+ ofproto_revalidate(ofproto,
+ mac_learning_changed(ofproto->ml, src_mac));
+ src_mac->port = flow->in_port;
}
}
/* Determine output port. */
- out_port = mac_learning_lookup_tag(ofproto->ml, flow->dl_dst, 0, tags,
- NULL);
- if (out_port < 0) {
+ dst_mac = mac_learning_lookup(ofproto->ml, flow->dl_dst, 0, tags);
+ if (!dst_mac) {
flood_packets(ofproto, flow->in_port, OFPPC_NO_FLOOD,
nf_output_iface, odp_actions);
- } else if (out_port != flow->in_port) {
- nl_msg_put_u32(odp_actions, ODP_ACTION_ATTR_OUTPUT, out_port);
- *nf_output_iface = out_port;
} else {
- /* Drop. */
+ int out_port = dst_mac->port;
+ if (out_port != flow->in_port) {
+ nl_msg_put_u32(odp_actions, ODP_ACTION_ATTR_OUTPUT, out_port);
+ *nf_output_iface = out_port;
+ } else {
+ /* Drop. */
+ }
}
return true;
update_learning_table(struct bridge *br, const struct flow *flow, int vlan,
struct port *in_port)
{
- enum grat_arp_lock_type lock_type;
- tag_type rev_tag;
-
- /* We don't want to learn from gratuitous ARP packets that are reflected
- * back over bond slaves so we lock the learning table. */
- lock_type = !is_gratuitous_arp(flow) ? GRAT_ARP_LOCK_NONE :
- (in_port->n_ifaces == 1) ? GRAT_ARP_LOCK_SET :
- GRAT_ARP_LOCK_CHECK;
-
- rev_tag = mac_learning_learn(br->ml, flow->dl_src, vlan, in_port->port_idx,
- lock_type);
- if (rev_tag) {
+ struct mac_entry *mac;
+
+ if (!mac_learning_may_learn(br->ml, flow->dl_src, vlan)) {
+ return;
+ }
+
+ mac = mac_learning_insert(br->ml, flow->dl_src, vlan);
+ if (is_gratuitous_arp(flow)) {
+ /* We don't want to learn from gratuitous ARP packets that are
+ * reflected back over bond slaves so we lock the learning table. */
+ if (in_port->n_ifaces == 1) {
+ mac_entry_set_grat_arp_lock(mac);
+ } else if (mac_entry_is_grat_arp_locked(mac)) {
+ return;
+ }
+ }
+
+ if (mac_entry_is_new(mac) || mac->port != in_port->port_idx) {
/* The log messages here could actually be useful in debugging,
* so keep the rate limit relatively high. */
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30,
- 300);
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30, 300);
VLOG_DBG_RL(&rl, "bridge %s: learned that "ETH_ADDR_FMT" is "
"on port %s in VLAN %d",
br->name, ETH_ADDR_ARGS(flow->dl_src),
in_port->name, vlan);
- ofproto_revalidate(br->ofproto, rev_tag);
+
+ mac->port = in_port->port_idx;
+ ofproto_revalidate(br->ofproto, mac_learning_changed(br->ml, mac));
}
}
/* Packets received on non-LACP bonds need special attention to avoid
* duplicates. */
if (in_port->n_ifaces > 1 && !lacp_negotiated(in_port->lacp)) {
- int src_idx;
- bool is_grat_arp_locked;
+ struct mac_entry *mac;
if (eth_addr_is_multicast(flow->dl_dst)) {
*tags |= port_get_active_iface_tag(in_port);
* to the exception is if we locked the learning table to avoid
* reflections on bond slaves. If this is the case, just drop the
* packet now. */
- src_idx = mac_learning_lookup(br->ml, flow->dl_src, vlan,
- &is_grat_arp_locked);
- if (src_idx != -1 && src_idx != in_port->port_idx &&
- (!is_gratuitous_arp(flow) || is_grat_arp_locked)) {
+ mac = mac_learning_lookup(br->ml, flow->dl_src, vlan, NULL);
+ if (mac && mac->port != in_port->port_idx &&
+ (!is_gratuitous_arp(flow) || mac_entry_is_grat_arp_locked(mac))) {
return false;
}
}
{
struct port *in_port;
struct port *out_port;
+ struct mac_entry *mac;
int vlan;
- int out_port_idx;
/* Check whether we should drop packets in this flow. */
if (!is_admissible(br, flow, packet != NULL, tags, &vlan, &in_port)) {
}
/* Determine output port. */
- out_port_idx = mac_learning_lookup_tag(br->ml, flow->dl_dst, vlan, tags,
- NULL);
- if (out_port_idx >= 0 && out_port_idx < br->n_ports) {
- out_port = br->ports[out_port_idx];
+ mac = mac_learning_lookup(br->ml, flow->dl_dst, vlan, tags);
+ if (mac && mac->port >= 0 && mac->port < br->n_ports) {
+ out_port = br->ports[mac->port];
} else if (!packet && !eth_addr_is_multicast(flow->dl_dst)) {
/* If we are revalidating but don't have a learning entry then
* eject the flow. Installing a flow that floods packets opens
projects / openvswitch / commitdiff