Re: [PATCH net-next v2 5/5] net: bridge: Refactor bridge port in locked mode to use jump labels

Nikolay Aleksandrov
2022-02-10T08:31:57Z

On 09/02/2022 15:05, Hans Schultz wrote:
> From: Hans Schultz <schultz.hans+lkml@gmail.com>
>
> As the locked mode feature is in the hot path of the bridge modules
> reception of packets, it needs to be refactored to use jump labels
> for optimization.
>
> Signed-off-by: Hans Schultz <schultz.hans+lkml@gmail.com>
> Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com>
> ---

Why two (almost) identical sign-offs?

Also, as Ido mentioned, please fold this patch into patch 01.

> net/bridge/br_input.c | 22 ++++++++++++++++++----
> net/bridge/br_netlink.c | 6 ++++++
> net/bridge/br_private.h | 2 ++
> 3 files changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
> index 469e3adbce07..6fc428d6bac5 100644
> --- a/net/bridge/br_input.c
> +++ b/net/bridge/br_input.c
> @@ -23,6 +23,18 @@
> #include "br_private.h"
> #include "br_private_tunnel.h"
>
> +static struct static_key_false br_input_locked_port_feature;
> +
> +void br_input_locked_port_add(void)
> +{
> + static_branch_inc(&br_input_locked_port_feature);
> +}
> +
> +void br_input_locked_port_remove(void)
> +{
> + static_branch_dec(&br_input_locked_port_feature);
> +}
> +
> static int
> br_netif_receive_skb(struct net *net, struct sock *sk, struct sk_buff *skb)
> {
> @@ -91,10 +103,12 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
> &state, &vlan))
> goto out;
>
> - if (p->flags & BR_PORT_LOCKED) {
> - fdb_entry = br_fdb_find_rcu(br, eth_hdr(skb)->h_source, vid);
> - if (!(fdb_entry && fdb_entry->dst == p))
> - goto drop;
> + if (static_branch_unlikely(&br_input_locked_port_feature)) {
> + if (p->flags & BR_PORT_LOCKED) {
> + fdb_entry = br_fdb_find_rcu(br, eth_hdr(skb)->h_source, vid);
> + if (!(fdb_entry && fdb_entry->dst == p))
> + goto drop;
> + }
> }
>
> nbp_switchdev_frame_mark(p, skb);
> diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
> index 7d4432ca9a20..e3dbe9fed75c 100644
> --- a/net/bridge/br_netlink.c
> +++ b/net/bridge/br_netlink.c
> @@ -860,6 +860,7 @@ static int br_set_port_state(struct net_bridge_port *p, u8 state)
> static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
> int attrtype, unsigned long mask)
> {
> + bool locked = p->flags & BR_PORT_LOCKED;
> if (!tb[attrtype])
> return;
>
> @@ -867,6 +868,11 @@ static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
> p->flags |= mask;
> else
> p->flags &= ~mask;
> +
> + if ((p->flags & BR_PORT_LOCKED) && !locked)
> + br_input_locked_port_add();
> + if (!(p->flags & BR_PORT_LOCKED) && locked)
> + br_input_locked_port_remove();
> }
>
> /* Process bridge protocol info on port */
> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> index 2661dda1a92b..0ec3ef897978 100644
> --- a/net/bridge/br_private.h
> +++ b/net/bridge/br_private.h
> @@ -832,6 +832,8 @@ void br_manage_promisc(struct net_bridge *br);
> int nbp_backup_change(struct net_bridge_port *p, struct net_device *backup_dev);
>
> /* br_input.c */
> +void br_input_locked_port_add(void);
> +void br_input_locked_port_remove(void);
> int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
> rx_handler_func_t *br_get_rx_handler(const struct net_device *dev);
>