From cd431e738509e74726055390c9e5e81e8e7e03ec Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 5 Feb 2013 20:22:50 +0000 Subject: [PATCH] macvlan: add multicast filter Setting up IPv6 addresses on configurations with many macvlans is not really working, as many multicast messages are dropped. Add a multicast filter to macvlan to reduce the amount of cloned skbs and overhead. Successfully tested with 1024 macvlans on one ethernet device. Signed-off-by: Eric Dumazet Cc: Ben Greear Signed-off-by: David S. Miller --- drivers/net/macvlan.c | 23 +++++++++++++++++++++++ include/linux/if_macvlan.h | 6 ++++++ 2 files changed, 29 insertions(+) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 7b44ebd7770e..f494da82c33f 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -126,6 +127,13 @@ static int macvlan_broadcast_one(struct sk_buff *skb, return vlan->receive(skb); } +static unsigned int mc_hash(const unsigned char *addr) +{ + u32 val = __get_unaligned_cpu32(addr + 2); + + return hash_32(val, MACVLAN_MC_FILTER_BITS); +} + static void macvlan_broadcast(struct sk_buff *skb, const struct macvlan_port *port, struct net_device *src, @@ -137,6 +145,7 @@ static void macvlan_broadcast(struct sk_buff *skb, struct sk_buff *nskb; unsigned int i; int err; + unsigned int hash = mc_hash(eth->h_dest); if (skb->protocol == htons(ETH_P_PAUSE)) return; @@ -146,6 +155,8 @@ static void macvlan_broadcast(struct sk_buff *skb, if (vlan->dev == src || !(vlan->mode & mode)) continue; + if (!test_bit(hash, vlan->mc_filter)) + continue; nskb = skb_clone(skb, GFP_ATOMIC); err = macvlan_broadcast_one(nskb, vlan, eth, mode == MACVLAN_MODE_BRIDGE); @@ -405,6 +416,18 @@ static void macvlan_set_mac_lists(struct net_device *dev) { struct macvlan_dev *vlan = netdev_priv(dev); + if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) { + bitmap_fill(vlan->mc_filter, MACVLAN_MC_FILTER_SZ); + } else { + struct netdev_hw_addr *ha; + DECLARE_BITMAP(filter, MACVLAN_MC_FILTER_SZ); + + bitmap_zero(filter, MACVLAN_MC_FILTER_SZ); + netdev_for_each_mc_addr(ha, dev) { + __set_bit(mc_hash(ha->addr), filter); + } + bitmap_copy(vlan->mc_filter, filter, MACVLAN_MC_FILTER_SZ); + } dev_uc_sync(vlan->lowerdev, dev); dev_mc_sync(vlan->lowerdev, dev); } diff --git a/include/linux/if_macvlan.h b/include/linux/if_macvlan.h index f65e8d250f7e..84dde1dd1da4 100644 --- a/include/linux/if_macvlan.h +++ b/include/linux/if_macvlan.h @@ -52,6 +52,9 @@ struct macvlan_pcpu_stats { */ #define MAX_MACVTAP_QUEUES (NR_CPUS < 16 ? NR_CPUS : 16) +#define MACVLAN_MC_FILTER_BITS 8 +#define MACVLAN_MC_FILTER_SZ (1 << MACVLAN_MC_FILTER_BITS) + struct macvlan_dev { struct net_device *dev; struct list_head list; @@ -59,6 +62,9 @@ struct macvlan_dev { struct macvlan_port *port; struct net_device *lowerdev; struct macvlan_pcpu_stats __percpu *pcpu_stats; + + DECLARE_BITMAP(mc_filter, MACVLAN_MC_FILTER_SZ); + enum macvlan_mode mode; u16 flags; int (*receive)(struct sk_buff *skb);