From e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 7 Jun 2013 08:48:57 -0700 Subject: igmp: hash a hash table to speedup ip_check_mc_rcu() After IP route cache removal, multicast applications using a lot of multicast addresses hit a O(N) behavior in ip_check_mc_rcu() Add a per in_device hash table to get faster lookup. This hash table is created only if the number of items in mc_list is above 4. Reported-by: Shawn Bohrer Signed-off-by: Eric Dumazet Tested-by: Shawn Bohrer Reviewed-by: Cong Wang Signed-off-by: David S. Miller --- include/linux/inetdevice.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/inetdevice.h') diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h index ea1e3b863890..b99cd23f3474 100644 --- a/include/linux/inetdevice.h +++ b/include/linux/inetdevice.h @@ -50,12 +50,17 @@ struct ipv4_devconf { DECLARE_BITMAP(state, IPV4_DEVCONF_MAX); }; +#define MC_HASH_SZ_LOG 9 + struct in_device { struct net_device *dev; atomic_t refcnt; int dead; struct in_ifaddr *ifa_list; /* IP ifaddr chain */ + struct ip_mc_list __rcu *mc_list; /* IP multicast filter chain */ + struct ip_mc_list __rcu * __rcu *mc_hash; + int mc_count; /* Number of installed mcasts */ spinlock_t mc_tomb_lock; struct ip_mc_list *mc_tomb; -- cgit v1.2.3