X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fmac-learning.c;h=f609d48e2a14b9043fab356a4adb1832dc3fd01f;hb=b0aa8146bf9ebb0794cf7ea39894f18db946da98;hp=bb84cfcc0b1ecba84db378c96041ea97ce3d84e0;hpb=16a5d1e4727db5c27a03d57d477512e07abe4988;p=sliver-openvswitch.git

diff --git a/lib/mac-learning.c b/lib/mac-learning.c
index bb84cfcc0..f609d48e2 100644
--- a/lib/mac-learning.c
+++ b/lib/mac-learning.c
@@ -1,5 +1,5 @@
 /*
- * 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.
@@ -28,6 +28,7 @@
 #include "poll-loop.h"
 #include "tag.h"
 #include "timeval.h"
+#include "unaligned.h"
 #include "util.h"
 #include "vlan-bitmap.h"
 #include "vlog.h"
@@ -37,19 +38,21 @@ VLOG_DEFINE_THIS_MODULE(mac_learning);
 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 *
@@ -98,9 +101,19 @@ get_lru(struct mac_learning *ml, struct mac_entry **e)
     }
 }
 
-/* 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;
 
@@ -109,6 +122,8 @@ mac_learning_create(void)
     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;
     return ml;
 }
 
@@ -146,10 +161,37 @@ mac_learning_set_flood_vlans(struct mac_learning *ml,
     }
 }
 
+/* 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'.
@@ -182,7 +224,7 @@ mac_learning_insert(struct mac_learning *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);
         }
@@ -199,7 +241,7 @@ mac_learning_insert(struct mac_learning *ml,
 
     /* 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;
 }
@@ -260,14 +302,18 @@ mac_learning_expire(struct mac_learning *ml, struct mac_entry *e)
     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);
@@ -277,7 +323,9 @@ void
 mac_learning_run(struct mac_learning *ml, struct tag_set *set)
 {
     struct mac_entry *e;
-    while (get_lru(ml, &e) && time_now() >= e->expires) {
+    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);
@@ -289,7 +337,9 @@ mac_learning_run(struct mac_learning *ml, struct tag_set *set)
 void
 mac_learning_wait(struct mac_learning *ml)
 {
-    if (!list_is_empty(&ml->lrus)) {
+    if (hmap_count(&ml->table) > ml->max_entries) {
+        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);
     }