diff mbox series

[net-next,v5,3/5] net: bridge: Add netlink knobs for number / max learned FDB entries

Message ID 20231016-fdb_limit-v5-3-32cddff87758@avm.de (mailing list archive)
State Accepted
Commit ddd1ad68826d8ff61a2e47733959570aa4d39a16
Delegated to: Netdev Maintainers
Headers show
Series bridge: Add a limit on learned FDB entries | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5506 this patch: 5506
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 1671 this patch: 1671
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 5871 this patch: 5871
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 47 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Johannes Nixdorf Oct. 16, 2023, 1:27 p.m. UTC
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(-)

Comments

Nikolay Aleksandrov Oct. 17, 2023, 9:31 a.m. UTC | #1
On 10/16/23 16:27, Johannes Nixdorf wrote:
> 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(-)
> 

Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Ido Schimmel Oct. 17, 2023, 11:06 a.m. UTC | #2
On Mon, Oct 16, 2023 at 03:27:22PM +0200, Johannes Nixdorf wrote:
> 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>

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
diff mbox series

Patch

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 10f0d33d8ccf..0c3cf6e6dea2 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -1265,6 +1265,8 @@  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_REJECT },
+	[IFLA_BR_FDB_MAX_LEARNED] = { .type = NLA_U32 },
 };
 
 static int br_changelink(struct net_device *brdev, struct nlattr *tb[],
@@ -1539,6 +1541,12 @@  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;
 }
 
@@ -1593,6 +1601,8 @@  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 */
@@ -1668,7 +1678,10 @@  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