netdev
[Top] [All Lists]

[PATCH] (3/4) bridge: get rid of threaded link for forwarding timeout

To: "David S. Miller" <davem@xxxxxxxxxxxxx>
Subject: [PATCH] (3/4) bridge: get rid of threaded link for forwarding timeout
From: Stephen Hemminger <shemminger@xxxxxxxx>
Date: Thu, 10 Mar 2005 15:44:34 -0800
Cc: netdev@xxxxxxxxxxx, bridge@xxxxxxxx
Organization: Open Source Development Lab
Sender: netdev-bounce@xxxxxxxxxxx
For 2.6, I changed the bridge forwarding table timeout code to keep
a threaded list of in order entries. Well, it turns out that this is
a performance hit because we end up constantly moving entries around
in the list.  Later patch changes this to be in place update with RCU.

This version just uses a 100ms garbage collection timer.

Signed-off-by: Stephen Hemminger <shemminger@xxxxxxxx>

--- a/net/bridge/br_fdb.c       2005-03-10 15:06:38 -08:00
+++ b/net/bridge/br_fdb.c       2005-03-10 15:06:38 -08:00
@@ -64,9 +64,6 @@
 static __inline__ void fdb_delete(struct net_bridge_fdb_entry *f)
 {
        hlist_del_rcu(&f->hlist);
-       if (!f->is_static)
-               list_del(&f->u.age_list);
-
        br_fdb_put(f);
 }
 
@@ -113,30 +110,23 @@
 void br_fdb_cleanup(unsigned long _data)
 {
        struct net_bridge *br = (struct net_bridge *)_data;
-       struct list_head *l, *n;
-       unsigned long delay;
+       unsigned long delay = hold_time(br);
+       int i;
 
        spin_lock_bh(&br->hash_lock);
-       delay = hold_time(br);
-
-       list_for_each_safe(l, n, &br->age_list) {
+       for (i = 0; i < BR_HASH_SIZE; i++) {
                struct net_bridge_fdb_entry *f;
-               unsigned long expires;
+               struct hlist_node *h, *n;
 
-               f = list_entry(l, struct net_bridge_fdb_entry, u.age_list);
-               expires = f->ageing_timer + delay;
-
-               if (time_before_eq(expires, jiffies)) {
-                       WARN_ON(f->is_static);
-                       pr_debug("expire age %lu jiffies %lu\n",
-                                f->ageing_timer, jiffies);
-                       fdb_delete(f);
-               } else {
-                       mod_timer(&br->gc_timer, expires);
-                       break;
+               hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
+                       if (!f->is_static && 
+                           time_before_eq(f->ageing_timer + delay, jiffies)) 
+                               fdb_delete(f);
                }
        }
        spin_unlock_bh(&br->hash_lock);
+
+       mod_timer(&br->gc_timer, jiffies + HZ/10);
 }
 
 void br_fdb_delete_by_port(struct net_bridge *br, struct net_bridge_port *p)
@@ -212,7 +202,7 @@
 static void fdb_rcu_free(struct rcu_head *head)
 {
        struct net_bridge_fdb_entry *ent
-               = container_of(head, struct net_bridge_fdb_entry, u.rcu);
+               = container_of(head, struct net_bridge_fdb_entry, rcu);
        kmem_cache_free(br_fdb_cache, ent);
 }
 
@@ -220,7 +210,7 @@
 void br_fdb_put(struct net_bridge_fdb_entry *ent)
 {
        if (atomic_dec_and_test(&ent->use_count))
-               call_rcu(&ent->u.rcu, fdb_rcu_free);
+               call_rcu(&ent->rcu, fdb_rcu_free);
 }
 
 /*
@@ -305,8 +295,6 @@
                        if (fdb->is_static)
                                return 0;
 
-                       /* move to end of age list */
-                       list_del(&fdb->u.age_list);
                        goto update;
                }
        }
@@ -329,8 +317,6 @@
        fdb->is_local = is_local;
        fdb->is_static = is_local;
        fdb->ageing_timer = jiffies;
-       if (!is_local) 
-               list_add_tail(&fdb->u.age_list, &br->age_list);
 
        return 0;
 }
diff -Nru a/net/bridge/br_private.h b/net/bridge/br_private.h
--- a/net/bridge/br_private.h   2005-03-10 15:06:38 -08:00
+++ b/net/bridge/br_private.h   2005-03-10 15:06:38 -08:00
@@ -46,10 +46,8 @@
 {
        struct hlist_node               hlist;
        struct net_bridge_port          *dst;
-       union {
-               struct list_head        age_list;
-               struct rcu_head         rcu;
-       } u;
+
+       struct rcu_head                 rcu;
        atomic_t                        use_count;
        unsigned long                   ageing_timer;
        mac_addr                        addr;
diff -Nru a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
--- a/net/bridge/br_stp_if.c    2005-03-10 15:06:38 -08:00
+++ b/net/bridge/br_stp_if.c    2005-03-10 15:06:38 -08:00
@@ -49,6 +49,8 @@
 
        spin_lock_bh(&br->lock);
        mod_timer(&br->hello_timer, jiffies + br->hello_time);
+       mod_timer(&br->gc_timer, jiffies + HZ/10);
+       
        br_config_bpdu_generation(br);
 
        list_for_each_entry(p, &br->port_list, list) {
@@ -78,6 +80,7 @@
        del_timer_sync(&br->hello_timer);
        del_timer_sync(&br->topology_change_timer);
        del_timer_sync(&br->tcn_timer);
+       del_timer_sync(&br->gc_timer);
 }
 
 /* called under bridge lock */
diff -Nru a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
--- a/net/bridge/br_fdb.c       2005-03-10 15:07:12 -08:00
+++ b/net/bridge/br_fdb.c       2005-03-10 15:07:12 -08:00
@@ -307,11 +307,6 @@
        atomic_set(&fdb->use_count, 1);
        hlist_add_head_rcu(&fdb->hlist, &br->hash[hash]);
 
-       if (!timer_pending(&br->gc_timer)) {
-               br->gc_timer.expires = jiffies + hold_time(br);
-               add_timer(&br->gc_timer);
-       }
-
  update:
        fdb->dst = source;
        fdb->is_local = is_local;

<Prev in Thread] Current Thread [Next in Thread>