/*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 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 "hash.h"
#include "list.h"
#include "poll-loop.h"
-#include "tag.h"
#include "timeval.h"
#include "unaligned.h"
#include "util.h"
#include "vlan-bitmap.h"
-#include "vlog.h"
-
-VLOG_DEFINE_THIS_MODULE(mac_learning);
COVERAGE_DEFINE(mac_learning_learned);
COVERAGE_DEFINE(mac_learning_expired);
}
static uint32_t
-mac_table_hash(const struct mac_learning *ml, const uint8_t mac[ETH_ADDR_LEN],
+mac_table_hash(const struct mac_learning *ml, const struct eth_addr mac,
uint16_t vlan)
{
- 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);
+ return hash_mac(mac, vlan, ml->secret);
}
static struct mac_entry *
-mac_entry_from_lru_node(struct list *list)
+mac_entry_from_lru_node(struct ovs_list *list)
{
return CONTAINER_OF(list, struct mac_entry, lru_node);
}
-/* Returns a tag that represents that 'mac' is on an unknown port in 'vlan'.
- * (When we learn where 'mac' is in 'vlan', this allows flows that were
- * flooded to be revalidated.) */
-static tag_type
-make_unknown_mac_tag(const struct mac_learning *ml,
- const uint8_t mac[ETH_ADDR_LEN], uint16_t vlan)
-{
- return tag_create_deterministic(mac_table_hash(ml, mac, vlan));
-}
-
static struct mac_entry *
mac_entry_lookup(const struct mac_learning *ml,
- const uint8_t mac[ETH_ADDR_LEN], uint16_t vlan)
+ const struct eth_addr mac, uint16_t vlan)
{
struct mac_entry *e;
return NULL;
}
+static struct mac_learning_port *
+mac_learning_port_lookup(struct mac_learning *ml, void *port)
+{
+ struct mac_learning_port *mlport;
+
+ HMAP_FOR_EACH_IN_BUCKET (mlport, hmap_node, hash_pointer(port, ml->secret),
+ &ml->ports_by_ptr) {
+ if (mlport->port == port) {
+ return mlport;
+ }
+ }
+ return NULL;
+}
+
+/* Changes the client-owned pointer for entry 'e' in 'ml' to 'port'. The
+ * pointer can be retrieved with mac_entry_get_port().
+ *
+ * The MAC-learning implementation treats the data that 'port' points to as
+ * opaque and never tries to dereference it. However, when a MAC learning
+ * table becomes overfull, so that eviction is required, the implementation
+ * does first evict MAC entries for the most common 'port's values in 'ml', so
+ * that there is a degree of fairness, that is, each port is entitled to its
+ * fair share of MAC entries. */
+void
+mac_entry_set_port(struct mac_learning *ml, struct mac_entry *e, void *port)
+ OVS_REQ_WRLOCK(ml->rwlock)
+{
+ if (mac_entry_get_port(ml, e) != port) {
+ ml->need_revalidate = true;
+
+ if (e->mlport) {
+ struct mac_learning_port *mlport = e->mlport;
+ list_remove(&e->port_lru_node);
+
+ if (list_is_empty(&mlport->port_lrus)) {
+ ovs_assert(mlport->heap_node.priority == 1);
+ hmap_remove(&ml->ports_by_ptr, &mlport->hmap_node);
+ heap_remove(&ml->ports_by_usage, &mlport->heap_node);
+ free(mlport);
+ } else {
+ ovs_assert(mlport->heap_node.priority > 1);
+ heap_change(&ml->ports_by_usage, &mlport->heap_node,
+ mlport->heap_node.priority - 1);
+ }
+ e->mlport = NULL;
+ }
+
+ if (port) {
+ struct mac_learning_port *mlport;
+
+ mlport = mac_learning_port_lookup(ml, port);
+ if (!mlport) {
+ mlport = xzalloc(sizeof *mlport);
+ hmap_insert(&ml->ports_by_ptr, &mlport->hmap_node,
+ hash_pointer(port, ml->secret));
+ heap_insert(&ml->ports_by_usage, &mlport->heap_node, 1);
+ mlport->port = port;
+ list_init(&mlport->port_lrus);
+ } else {
+ heap_change(&ml->ports_by_usage, &mlport->heap_node,
+ mlport->heap_node.priority + 1);
+ }
+ list_push_back(&mlport->port_lrus, &e->port_lru_node);
+ e->mlport = mlport;
+ }
+ }
+}
+
+/* Finds one of the ports with the most MAC entries and evicts its least
+ * recently used entry. */
+static void
+evict_mac_entry_fairly(struct mac_learning *ml)
+ OVS_REQ_WRLOCK(ml->rwlock)
+{
+ struct mac_learning_port *mlport;
+ struct mac_entry *e;
+
+ mlport = CONTAINER_OF(heap_max(&ml->ports_by_usage),
+ struct mac_learning_port, heap_node);
+ e = CONTAINER_OF(list_front(&mlport->port_lrus),
+ struct mac_entry, port_lru_node);
+ mac_learning_expire(ml, e);
+}
+
/* If the LRU list is not empty, stores the least-recently-used entry in '*e'
* and returns true. Otherwise, if the LRU list is empty, stores NULL in '*e'
* and return false. */
static bool
get_lru(struct mac_learning *ml, struct mac_entry **e)
+ OVS_REQ_RDLOCK(ml->rwlock)
{
if (!list_is_empty(&ml->lrus)) {
*e = mac_entry_from_lru_node(ml->lrus.next);
ml->flood_vlans = NULL;
ml->idle_time = normalize_idle_time(idle_time);
ml->max_entries = MAC_DEFAULT_MAX;
+ ml->need_revalidate = false;
+ hmap_init(&ml->ports_by_ptr);
+ heap_init(&ml->ports_by_usage);
+ ovs_refcount_init(&ml->ref_cnt);
+ ovs_rwlock_init(&ml->rwlock);
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_refcount_ref(&ml->ref_cnt);
+ }
+ return ml;
+}
+
+/* Unreferences (and possibly destroys) MAC learning table 'ml'. */
+void
+mac_learning_unref(struct mac_learning *ml)
+{
+ if (ml && ovs_refcount_unref(&ml->ref_cnt) == 1) {
struct mac_entry *e, *next;
+ ovs_rwlock_wrlock(&ml->rwlock);
HMAP_FOR_EACH_SAFE (e, next, hmap_node, &ml->table) {
- hmap_remove(&ml->table, &e->hmap_node);
- free(e);
+ mac_learning_expire(ml, e);
}
hmap_destroy(&ml->table);
+ hmap_destroy(&ml->ports_by_ptr);
+ heap_destroy(&ml->ports_by_usage);
bitmap_free(ml->flood_vlans);
+ ovs_rwlock_unlock(&ml->rwlock);
+ ovs_rwlock_destroy(&ml->rwlock);
free(ml);
}
}
* '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)
+ const struct eth_addr src_mac, uint16_t vlan)
{
return ml && is_learning_vlan(ml, vlan) && !eth_addr_is_multicast(src_mac);
}
* by calling mac_learning_may_learn(), that 'src_mac' and 'vlan' are
* learnable.
*
- * 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. */
+ * If the returned MAC entry is new (that is, if it has a NULL client-provided
+ * port, as returned by mac_entry_get_port()), then the caller must initialize
+ * the new entry's port to a nonnull value with mac_entry_set_port(). */
struct mac_entry *
mac_learning_insert(struct mac_learning *ml,
- const uint8_t src_mac[ETH_ADDR_LEN], uint16_t vlan)
+ const struct eth_addr src_mac, uint16_t vlan)
{
struct mac_entry *e;
uint32_t hash = mac_table_hash(ml, src_mac, vlan);
if (hmap_count(&ml->table) >= ml->max_entries) {
- get_lru(ml, &e);
- mac_learning_expire(ml, e);
+ evict_mac_entry_fairly(ml);
}
e = xmalloc(sizeof *e);
hmap_insert(&ml->table, &e->hmap_node, hash);
- memcpy(e->mac, src_mac, ETH_ADDR_LEN);
+ e->mac = src_mac;
e->vlan = vlan;
- e->tag = 0;
e->grat_arp_lock = TIME_MIN;
+ e->mlport = NULL;
+ COVERAGE_INC(mac_learning_learned);
} else {
list_remove(&e->lru_node);
}
/* Mark 'e' as recently used. */
list_push_back(&ml->lrus, &e->lru_node);
+ if (e->mlport) {
+ list_remove(&e->port_lru_node);
+ list_push_back(&e->mlport->port_lrus, &e->port_lru_node);
+ }
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.)
- *
- * 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 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' 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'. */
+ * learning entry, if any. */
struct mac_entry *
mac_learning_lookup(const struct mac_learning *ml,
- const uint8_t dst[ETH_ADDR_LEN], uint16_t vlan,
- tag_type *tag)
+ const struct eth_addr dst, uint16_t vlan)
{
if (eth_addr_is_multicast(dst)) {
/* No tag because the treatment of multicast destinations never
} else {
struct mac_entry *e = mac_entry_lookup(ml, dst, vlan);
- 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);
- }
+ ovs_assert(e == NULL || mac_entry_get_port(ml, e) != NULL);
return e;
}
}
void
mac_learning_expire(struct mac_learning *ml, struct mac_entry *e)
{
+ ml->need_revalidate = true;
+ mac_entry_set_port(ml, e, NULL);
hmap_remove(&ml->table, &e->hmap_node);
list_remove(&e->lru_node);
free(e);
}
-/* 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. */
+/* Expires all the mac-learning entries in 'ml'. */
void
-mac_learning_flush(struct mac_learning *ml, struct tag_set *tags)
+mac_learning_flush(struct mac_learning *ml)
{
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);
}
-void
-mac_learning_run(struct mac_learning *ml, struct tag_set *set)
+/* Does periodic work required by 'ml'. Returns true if something changed that
+ * may require flow revalidation. */
+bool
+mac_learning_run(struct mac_learning *ml)
{
+ bool need_revalidate;
struct mac_entry *e;
+
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);
- }
mac_learning_expire(ml, e);
}
+
+ need_revalidate = ml->need_revalidate;
+ ml->need_revalidate = false;
+ return need_revalidate;
}
void
mac_learning_wait(struct mac_learning *ml)
{
- if (hmap_count(&ml->table) > ml->max_entries) {
+ if (hmap_count(&ml->table) > ml->max_entries
+ || ml->need_revalidate) {
poll_immediate_wake();
} else if (!list_is_empty(&ml->lrus)) {
struct mac_entry *e = mac_entry_from_lru_node(ml->lrus.next);
projects / cascardo / ovs.git / blobdiff