On 16-03-01 09:00 AM, Amir Vadai wrote: > On Tue, Mar 01, 2016 at 03:52:08PM +0100, Jiri Pirko wrote: >> Tue, Mar 01, 2016 at 03:24:48PM CET, a...@vadai.me wrote: >>> Extend ndo_setup_tc() to support ingress tc offloading. Will be used by >>> later patches to offload tc flower filter. >>> >>> Feature is off by default and could be enabled by issuing: >>> # ethtool -K eth0 hw-tc-offload on >>> >>> Offloads flow table is dynamically created when first filter is >>> added. >>> Rules are saved in a hash table that is maintained by the consumer (for >>> example - the flower offload in the next patch). >>> When last filter is removed and no filters exist in the hash table, the >>> offload flow table is destroyed. >> >> <snip> >> >>> @@ -1880,6 +1883,17 @@ static int mlx5e_setup_tc(struct net_device *netdev, >>> u8 tc) >>> static int mlx5e_ndo_setup_tc(struct net_device *dev, u32 handle, >>> __be16 proto, struct tc_to_netdev *tc) >>> { >>> + struct mlx5e_priv *priv = netdev_priv(dev); >>> + >>> + if (TC_H_MAJ(handle) != TC_H_MAJ(TC_H_INGRESS)) >>> + goto mqprio; >>> + >>> + switch (tc->type) { >>> + default: >>> + return -EINVAL; >> >> -EOPNOTSUPP would be better here perhaps? >> >> >>> + } >>> + >>> +mqprio: >>> if (handle != TC_H_ROOT || tc->type != TC_SETUP_MQPRIO) >>> return -EINVAL; >>> >>> @@ -1963,6 +1977,13 @@ static int mlx5e_set_features(struct net_device >>> *netdev, >>> mlx5e_disable_vlan_filter(priv); >>> } >>> >>> + if ((changes & NETIF_F_HW_TC) && !(features & NETIF_F_HW_TC) && >>> + mlx5e_tc_num_filters(priv)) { >>> + netdev_err(netdev, >>> + "Active offloaded tc filters, can't turn >>> hw_tc_offload off\n"); >>> + return -EINVAL; >> >> This should not fail I believe. Just disable it in hw. I would even toss >> away the rules if necessary. > It depends on the answer regarding your comment on the previous patch. > If we have the rule in both SW and HW, and remove it from the HW it is > ok (although, currently I don't understand why would anyone want in both > places). > If the rule is processed by HW only - turning off this flag, will > disable the offloaded rules - it might be misleading, so I prefered not > to allow it and print a message.
When we get the HW only mode we will need to also flush the hardware representation in software as well as the hardware state.