The previous patch added accounting and a limit for the number of dynamically learned FDB entries per bridge. However it did not provide means to actually configure those bounds or read back the count. This patch does that.
Two new netlink attributes are added for the accounting and limit of dynamically learned FDB entries: - IFLA_BR_FDB_N_LEARNED (RO) for the number of entries accounted for a single bridge. - IFLA_BR_FDB_MAX_LEARNED (RW) for the configured limit of entries for the bridge.
The new attributes are used like this:
# ip link add name br up type bridge fdb_max_learned 256 # ip link add name v1 up master br type veth peer v2 # ip link set up dev v2 # mausezahn -a rand -c 1024 v2 0.01 seconds (90877 packets per second # bridge fdb | grep -v permanent | wc -l 256 # ip -d link show dev br 13: br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 [...] [...] fdb_n_learned 256 fdb_max_learned 256
Signed-off-by: Johannes Nixdorf jnixdorf-oss@avm.de --- include/uapi/linux/if_link.h | 2 ++ net/bridge/br_netlink.c | 15 ++++++++++++++- 2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index ce3117df9cec..0486f314c176 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -510,6 +510,8 @@ enum { IFLA_BR_VLAN_STATS_PER_PORT, IFLA_BR_MULTI_BOOLOPT, IFLA_BR_MCAST_QUERIER_STATE, + IFLA_BR_FDB_N_LEARNED, + IFLA_BR_FDB_MAX_LEARNED, __IFLA_BR_MAX, };
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 505683ef9a26..f5d49a05e61b 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -1267,6 +1267,8 @@ static const struct nla_policy br_policy[IFLA_BR_MAX + 1] = { [IFLA_BR_VLAN_STATS_PER_PORT] = { .type = NLA_U8 }, [IFLA_BR_MULTI_BOOLOPT] = NLA_POLICY_EXACT_LEN(sizeof(struct br_boolopt_multi)), + [IFLA_BR_FDB_N_LEARNED] = { .type = NLA_U32 }, + [IFLA_BR_FDB_MAX_LEARNED] = { .type = NLA_U32 }, };
static int br_changelink(struct net_device *brdev, struct nlattr *tb[], @@ -1541,6 +1543,12 @@ static int br_changelink(struct net_device *brdev, struct nlattr *tb[], return err; }
+ if (data[IFLA_BR_FDB_MAX_LEARNED]) { + u32 val = nla_get_u32(data[IFLA_BR_FDB_MAX_LEARNED]); + + WRITE_ONCE(br->fdb_max_learned, val); + } + return 0; }
@@ -1595,6 +1603,8 @@ static size_t br_get_size(const struct net_device *brdev) nla_total_size_64bit(sizeof(u64)) + /* IFLA_BR_TOPOLOGY_CHANGE_TIMER */ nla_total_size_64bit(sizeof(u64)) + /* IFLA_BR_GC_TIMER */ nla_total_size(ETH_ALEN) + /* IFLA_BR_GROUP_ADDR */ + nla_total_size(sizeof(u32)) + /* IFLA_BR_FDB_N_LEARNED */ + nla_total_size(sizeof(u32)) + /* IFLA_BR_FDB_MAX_LEARNED */ #ifdef CONFIG_BRIDGE_IGMP_SNOOPING nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_ROUTER */ nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_SNOOPING */ @@ -1670,7 +1680,10 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev) nla_put_u8(skb, IFLA_BR_TOPOLOGY_CHANGE_DETECTED, br->topology_change_detected) || nla_put(skb, IFLA_BR_GROUP_ADDR, ETH_ALEN, br->group_addr) || - nla_put(skb, IFLA_BR_MULTI_BOOLOPT, sizeof(bm), &bm)) + nla_put(skb, IFLA_BR_MULTI_BOOLOPT, sizeof(bm), &bm) || + nla_put_u32(skb, IFLA_BR_FDB_N_LEARNED, + atomic_read(&br->fdb_n_learned)) || + nla_put_u32(skb, IFLA_BR_FDB_MAX_LEARNED, br->fdb_max_learned)) return -EMSGSIZE;
#ifdef CONFIG_BRIDGE_VLAN_FILTERING