0001-bridge-only-expire-the-mdb-entry-when-query-is-recei.patch

   1 From 88654a86563317f36c38a279ea47e7aa09892192 Mon Sep 17 00:00:00 2001
   2 From: Alexandre Derumier <aderumier@odiso.com>
   3 Date: Mon, 3 Jun 2013 17:26:49 +0200
   4 Subject: [PATCH 1/2] bridge: only expire the mdb entry when query is received
   5
   6 Currently we arm the expire timer when the mdb entry is added, however,
   7 this causes problem when there is no querier sent
   8 out after that.
   9
  10 So we should only arm the timer when a corresponding query is received, as suggested by Herbert.
  11 And he also mentioned "if there is no querier then group subscriptions shouldn't expire.
  12 There has to be at least one querier in the network for this thing to work.
  13 Otherwise it just degenerates into a non-snooping switch, which is OK."
  14
  15 Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
  16 ---
  17  net/bridge/br_multicast.c |   37 +++++++++++--------------------------
  18  net/bridge/br_private.h   |    1 +
  19  2 files changed, 12 insertions(+), 26 deletions(-)
  20
  21 diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
  22 index 97b06de..ceb364a 100644
  23 --- a/net/bridge/br_multicast.c
  24 +++ b/net/bridge/br_multicast.c
  25 @@ -677,8 +677,6 @@ rehash:
  26
  27         mp->br = br;
  28         mp->addr = *group;
  29 -       setup_timer(&mp->timer, br_multicast_group_expired,
  30 -                   (unsigned long)mp);
  31         setup_timer(&mp->query_timer, br_multicast_group_query_expired,
  32                     (unsigned long)mp);
  33
  34 @@ -696,7 +694,6 @@ static int br_multicast_add_group(struct net_bridge *br,
  35         struct net_bridge_mdb_entry *mp;
  36         struct net_bridge_port_group *p;
  37         struct net_bridge_port_group **pp;
  38 -       unsigned long now = jiffies;
  39         int err;
  40
  41         spin_lock(&br->multicast_lock);
  42 @@ -712,13 +709,12 @@ static int br_multicast_add_group(struct net_bridge *br,
  43         if (!port) {
  44                 if (hlist_unhashed(&mp->mglist))
  45                         hlist_add_head(&mp->mglist, &br->mglist);
  46 -               mod_timer(&mp->timer, now + br->multicast_membership_interval);
  47                 goto out;
  48         }
  49
  50         for (pp = &mp->ports; (p = *pp); pp = &p->next) {
  51                 if (p->port == port)
  52 -                       goto found;
  53 +                       goto out;
  54                 if ((unsigned long)p->port < (unsigned long)port)
  55                         break;
  56         }
  57 @@ -739,8 +735,6 @@ static int br_multicast_add_group(struct net_bridge *br,
  58
  59         rcu_assign_pointer(*pp, p);
  60
  61 -found:
  62 -       mod_timer(&p->timer, now + br->multicast_membership_interval);
  63  out:
  64         err = 0;
  65
  66 @@ -1151,6 +1145,10 @@ static int br_ip4_multicast_query(struct net_bridge *br,
  67         if (!mp)
  68                 goto out;
  69
  70 +        setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp);
  71 +        mod_timer(&mp->timer, now + br->multicast_membership_interval);
  72 +        mp->timer_armed = true;
  73 +
  74         max_delay *= br->multicast_last_member_count;
  75
  76         if (!hlist_unhashed(&mp->mglist) &&
  77 @@ -1220,6 +1218,10 @@ static int br_ip6_multicast_query(struct net_bridge *br,
  78         if (!mp)
  79                 goto out;
  80
  81 +       setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp);
  82 +       mod_timer(&mp->timer, now + br->multicast_membership_interval);
  83 +       mp->timer_armed = true;
  84 +
  85         max_delay *= br->multicast_last_member_count;
  86         if (!hlist_unhashed(&mp->mglist) &&
  87             (timer_pending(&mp->timer) ?
  88 @@ -1266,7 +1268,7 @@ static void br_multicast_leave_group(struct net_bridge *br,
  89                      br->multicast_last_member_interval;
  90
  91         if (!port) {
  92 -               if (!hlist_unhashed(&mp->mglist) &&
  93 +               if (!hlist_unhashed(&mp->mglist) && mp->timer_armed &&
  94                     (timer_pending(&mp->timer) ?
  95                      time_after(mp->timer.expires, time) :
  96                      try_to_del_timer_sync(&mp->timer) >= 0)) {
  97 @@ -1276,24 +1278,6 @@ static void br_multicast_leave_group(struct net_bridge *br,
  98                         mod_timer(&mp->query_timer, now);
  99                 }
 100
 101 -               goto out;
 102 -       }
 103 -
 104 -       for (p = mp->ports; p; p = p->next) {
 105 -               if (p->port != port)
 106 -                       continue;
 107 -
 108 -               if (!hlist_unhashed(&p->mglist) &&
 109 -                   (timer_pending(&p->timer) ?
 110 -                    time_after(p->timer.expires, time) :
 111 -                    try_to_del_timer_sync(&p->timer) >= 0)) {
 112 -                       mod_timer(&p->timer, time);
 113 -
 114 -                       p->queries_sent = 0;
 115 -                       mod_timer(&p->query_timer, now);
 116 -               }
 117 -
 118 -               break;
 119         }
 120
 121  out:
 122 @@ -1650,6 +1634,7 @@ void br_multicast_stop(struct net_bridge *br)
 123                 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
 124                                           hlist[ver]) {
 125                         del_timer(&mp->timer);
 126 +                       mp->timer_armed = false;
 127                         del_timer(&mp->query_timer);
 128                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 129                 }
 130 diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
 131 index 03a4afc..e8ecef1 100644
 132 --- a/net/bridge/br_private.h
 133 +++ b/net/bridge/br_private.h
 134 @@ -91,6 +91,7 @@ struct net_bridge_mdb_entry
 135         struct timer_list               query_timer;
 136         struct br_ip                    addr;
 137         u32                             queries_sent;
 138 +       bool                            timer_armed;
 139  };
 140
 141  struct net_bridge_mdb_htable
 142 --
 143 1.7.10.4
 144