/*
- * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "mac-learning.h"
-#include <assert.h>
#include <inttypes.h>
#include <stdlib.h>
#include "poll-loop.h"
#include "tag.h"
#include "timeval.h"
+#include "unaligned.h"
#include "util.h"
#include "vlan-bitmap.h"
#include "vlog.h"
COVERAGE_DEFINE(mac_learning_learned);
COVERAGE_DEFINE(mac_learning_expired);
-/* Returns the number of seconds since 'e' was last learned. */
+/* Returns the number of seconds since 'e' (within 'ml') was last learned. */
int
-mac_entry_age(const struct mac_entry *e)
+mac_entry_age(const struct mac_learning *ml, const struct mac_entry *e)
{
time_t remaining = e->expires - time_now();
- return MAC_ENTRY_IDLE_TIME - remaining;
+ return ml->idle_time - remaining;
}
static uint32_t
mac_table_hash(const struct mac_learning *ml, const uint8_t mac[ETH_ADDR_LEN],
uint16_t vlan)
{
- return hash_bytes(mac, ETH_ADDR_LEN, vlan ^ ml->secret);
+ unsigned int mac1 = get_unaligned_u32((uint32_t *) mac);
+ unsigned int mac2 = get_unaligned_u16((uint16_t *) (mac + 4));
+ return hash_3words(mac1, mac2 | (vlan << 16), ml->secret);
}
static struct mac_entry *
}
}
-/* Creates and returns a new MAC learning table. */
+static unsigned int
+normalize_idle_time(unsigned int idle_time)
+{
+ return (idle_time < 15 ? 15
+ : idle_time > 3600 ? 3600
+ : idle_time);
+}
+
+/* Creates and returns a new MAC learning table with an initial MAC aging
+ * timeout of 'idle_time' seconds and an initial maximum of MAC_DEFAULT_MAX
+ * entries. */
struct mac_learning *
-mac_learning_create(void)
+mac_learning_create(unsigned int idle_time)
{
struct mac_learning *ml;
hmap_init(&ml->table);
ml->secret = random_uint32();
ml->flood_vlans = NULL;
+ ml->idle_time = normalize_idle_time(idle_time);
+ ml->max_entries = MAC_DEFAULT_MAX;
+ tag_set_init(&ml->tags);
+ ml->ref_cnt = 1;
return ml;
}
-/* Destroys MAC learning table 'ml'. */
-void
-mac_learning_destroy(struct mac_learning *ml)
+struct mac_learning *
+mac_learning_ref(const struct mac_learning *ml_)
{
+ struct mac_learning *ml = CONST_CAST(struct mac_learning *, ml_);
if (ml) {
+ ovs_assert(ml->ref_cnt > 0);
+ ml->ref_cnt++;
+ }
+ return ml;
+}
+
+/* Unreferences (and possibly destroys) MAC learning table 'ml'. */
+void
+mac_learning_unref(struct mac_learning *ml)
+{
+ if (!ml) {
+ return;
+ }
+
+ ovs_assert(ml->ref_cnt > 0);
+ if (!--ml->ref_cnt) {
struct mac_entry *e, *next;
HMAP_FOR_EACH_SAFE (e, next, hmap_node, &ml->table) {
}
}
+/* Changes the MAC aging timeout of 'ml' to 'idle_time' seconds. */
+void
+mac_learning_set_idle_time(struct mac_learning *ml, unsigned int idle_time)
+{
+ idle_time = normalize_idle_time(idle_time);
+ if (idle_time != ml->idle_time) {
+ struct mac_entry *e;
+ int delta;
+
+ delta = (int) idle_time - (int) ml->idle_time;
+ LIST_FOR_EACH (e, lru_node, &ml->lrus) {
+ e->expires += delta;
+ }
+ ml->idle_time = idle_time;
+ }
+}
+
+/* Sets the maximum number of entries in 'ml' to 'max_entries', adjusting it
+ * to be within a reasonable range. */
+void
+mac_learning_set_max_entries(struct mac_learning *ml, size_t max_entries)
+{
+ ml->max_entries = (max_entries < 10 ? 10
+ : max_entries > 1000 * 1000 ? 1000 * 1000
+ : max_entries);
+}
+
static bool
is_learning_vlan(const struct mac_learning *ml, uint16_t vlan)
{
- return vlan_bitmap_contains(ml->flood_vlans, vlan);
+ return !ml->flood_vlans || !bitmap_is_set(ml->flood_vlans, vlan);
}
/* Returns true if 'src_mac' may be learned on 'vlan' for 'ml'.
if (!e) {
uint32_t hash = mac_table_hash(ml, src_mac, vlan);
- if (hmap_count(&ml->table) >= MAC_MAX) {
+ if (hmap_count(&ml->table) >= ml->max_entries) {
get_lru(ml, &e);
mac_learning_expire(ml, e);
}
/* Mark 'e' as recently used. */
list_push_back(&ml->lrus, &e->lru_node);
- e->expires = time_now() + MAC_ENTRY_IDLE_TIME;
+ e->expires = time_now() + ml->idle_time;
return e;
}
-/* 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.)
+/* Changes 'e''s tag to a new, randomly selected one. Causes
+ * mac_learning_run() to flag for revalidation 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
+void
mac_learning_changed(struct mac_learning *ml, struct mac_entry *e)
{
- tag_type old_tag = e->tag;
+ tag_type tag = e->tag ? e->tag : make_unknown_mac_tag(ml, e->mac, e->vlan);
COVERAGE_INC(mac_learning_learned);
e->tag = tag_create_random();
- return old_tag ? old_tag : make_unknown_mac_tag(ml, e->mac, e->vlan);
+ tag_set_add(&ml->tags, tag);
}
/* Looks up MAC 'dst' for VLAN 'vlan' in 'ml' and returns the associated MAC
} else {
struct mac_entry *e = mac_entry_lookup(ml, dst, vlan);
- assert(e == NULL || e->tag != 0);
+ ovs_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);
free(e);
}
-/* Expires all the mac-learning entries in 'ml'. The tags in 'ml' are
- * discarded, so the client is responsible for revalidating any flows that
- * depend on 'ml', if necessary. */
+/* Expires all the mac-learning entries in 'ml'. If not NULL, the tags in 'ml'
+ * are added to 'tags'. Otherwise the tags in 'ml' are discarded. The client
+ * is responsible for revalidating any flows that depend on 'ml', if
+ * necessary. */
void
-mac_learning_flush(struct mac_learning *ml)
+mac_learning_flush(struct mac_learning *ml, struct tag_set *tags)
{
struct mac_entry *e;
while (get_lru(ml, &e)){
+ if (tags) {
+ tag_set_add(tags, e->tag);
+ }
mac_learning_expire(ml, e);
}
hmap_shrink(&ml->table);
mac_learning_run(struct mac_learning *ml, struct tag_set *set)
{
struct mac_entry *e;
- while (get_lru(ml, &e) && time_now() >= e->expires) {
+
+ if (set) {
+ tag_set_union(set, &ml->tags);
+ }
+ tag_set_init(&ml->tags);
+
+ while (get_lru(ml, &e)
+ && (hmap_count(&ml->table) > ml->max_entries
+ || time_now() >= e->expires)) {
COVERAGE_INC(mac_learning_expired);
if (set) {
tag_set_add(set, e->tag);
void
mac_learning_wait(struct mac_learning *ml)
{
- if (!list_is_empty(&ml->lrus)) {
+ if (hmap_count(&ml->table) > ml->max_entries
+ || !tag_set_is_empty(&ml->tags)) {
+ poll_immediate_wake();
+ } else if (!list_is_empty(&ml->lrus)) {
struct mac_entry *e = mac_entry_from_lru_node(ml->lrus.next);
poll_timer_wait_until(e->expires * 1000LL);
}