Re: [PATCH net-next] net: ethernet: ti: cpsw: don't flush mcast entries while switch promisc mode

From: Grygorii Strashko
Date: Thu Oct 18 2018 - 20:03:12 EST

On 10/18/18 1:00 PM, Ivan Khoronzhuk wrote:
No need now to flush mcast entries in switch mode while toggling to
promiscuous mode. It's not needed as vlan reg_mcast = ALL_PORTS
and mcast/vlan ports = ALL_PORTS, the same happening for vlan
unreg_mcast, it's set to ALL_PORT_MASK just after calling promisc
mode routine by calling set allmulti. I suppose main reason to flush
them is to use unreg_mcast to receive all to host port. Thus, now, all
mcast packets are received anyway and no reason to flush mcast entries
unsafely, as they were synced with __dev_mc_sync() previously and are
not restored. Another way is to _dev_mc_unsync() them, but no need.

User have possibility to add additional mcast entries or edit existing in switch-mode, which is now done using custom tool. So, Host in promisc
mode will not receive packets for mcast address X if port mask for this
addr set to (ALL_PORTS - HOST_PORT). Am I missing smth?

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>

Based on net-next/master
Tasted on am572x EVM and BBB

drivers/net/ethernet/ti/cpsw.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 226be2a56c1f..0e475020a674 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -638,9 +638,6 @@ static void cpsw_set_promiscious(struct net_device *ndev, bool enable)
} while (time_after(timeout, jiffies));
cpsw_ale_control_set(ale, 0, ALE_AGEOUT, 1);
- /* Clear all mcast from ALE */
- cpsw_ale_flush_multicast(ale, ALE_ALL_PORTS, -1);
/* Flood All Unicast Packets to Host port */
cpsw_ale_control_set(ale, 0, ALE_P0_UNI_FLOOD, 1);
dev_dbg(&ndev->dev, "promiscuity enabled\n");