Re: [PATCH net-next v2 0/3] net: ethernet: ti: cpsw: enable bc/mc storm prevention support

[Vladimir Oltean]

On Mon, Nov 01, 2021 at 07:01:19PM +0200, Grygorii Strashko wrote:
> Hi
> 
> This series first adds supports for the ALE feature to rate limit number ingress
> broadcast(BC)/multicast(MC) packets per/sec which main purpose is BC/MC storm
> prevention.
> 
> And then enables corresponding support for ingress broadcast(BC)/multicast(MC)
> packets rate limiting for TI CPSW switchdev and AM65x/J221E CPSW_NUSS drivers by
> implementing HW offload for simple tc-flower with policer action with matches
> on dst_mac:
>  - ff:ff:ff:ff:ff:ff has to be used for BC packets rate limiting
>  - 01:00:00:00:00:00 fixed value has to be used for MC packets rate limiting
> 
> Examples:
> - BC rate limit to 1000pps:
>   tc qdisc add dev eth0 clsact
>   tc filter add dev eth0 ingress flower skip_sw dst_mac ff:ff:ff:ff:ff:ff \
>   action police pkts_rate 1000 pkts_burst 1
> 
> - MC rate limit to 20000pps:
>   tc qdisc add dev eth0 clsact
>   tc filter add dev eth0 ingress flower skip_sw dst_mac 01:00:00:00:00:00 \
>   action police pkts_rate 10000 pkts_burst 1
> 
>   pkts_burst - not used.
> 
> The solution inspired patch from Vladimir Oltean [1].
> 
> Changes in v2:
>  - switch to packet-per-second policing introduced by
>    commit 2ffe0395288a ("net/sched: act_police: add support for packet-per-second policing") [2]
> 
> v1: https://patchwork.kernel.org/project/netdevbpf/cover/20201114035654.32658-1-grygorii.strashko@xxxxxx/
> 
> [1] https://lore.kernel.org/patchwork/patch/1217254/
> [2] https://patchwork.kernel.org/project/netdevbpf/cover/20210312140831.23346-1-simon.horman@xxxxxxxxxxxxx/
> 
> Grygorii Strashko (3):
>   drivers: net: cpsw: ale: add broadcast/multicast rate limit support
>   net: ethernet: ti: am65-cpsw: enable bc/mc storm prevention support
>   net: ethernet: ti: cpsw_new: enable bc/mc storm prevention support
> 
>  drivers/net/ethernet/ti/am65-cpsw-qos.c | 145 ++++++++++++++++++++
>  drivers/net/ethernet/ti/am65-cpsw-qos.h |   8 ++
>  drivers/net/ethernet/ti/cpsw_ale.c      |  66 +++++++++
>  drivers/net/ethernet/ti/cpsw_ale.h      |   2 +
>  drivers/net/ethernet/ti/cpsw_new.c      |   4 +-
>  drivers/net/ethernet/ti/cpsw_priv.c     | 170 ++++++++++++++++++++++++
>  drivers/net/ethernet/ti/cpsw_priv.h     |   8 ++
>  7 files changed, 402 insertions(+), 1 deletion(-)
> 
> -- 
> 2.17.1
>

I don't think I've asked this for v1, but when you say multicast storm
control, does the hardware police just unknown multicast frames, or all
multicast frames?