From: Davide Caratti <dcara...@redhat.com>
Date: Wed, 7 Nov 2018 11:28:18 +0100
> GSO tunneled packets are always segmented in software before they are
> transmitted by a VLAN, even when the lower device can offload tunnel
> encapsulation and VLAN together (i.e., some bits in NETIF_F_GSO_ENCAP_ALL
> mask are set in the lower device 'vlan_features'). If we let VLANs have
> the same tunnel offload capabilities as their lower device, throughput
> can improve significantly when CPU is limited on the transmitter side.
>
> - set NETIF_F_GSO_ENCAP_ALL bits in the VLAN 'hw_features', to ensure
> that 'features' will have those bits zeroed only when the lower device
> has no hardware support for tunnel encapsulation.
> - for the same reason, copy GSO-related bits of 'hw_enc_features' from
> lower device to VLAN, and ensure to update that value when the lower
> device changes its features.
> - set NETIF_F_HW_CSUM bit in the VLAN 'hw_enc_features' if 'real_dev'
> is able to compute checksums at least for a kind of packets, like done
> with commit 8403debeead8 ("vlan: Keep NETIF_F_HW_CSUM similar to other
> software devices"). This avoids software segmentation due to mismatching
> checksum capabilities between VLAN's 'features' and 'hw_enc_features'.
>
> Reported-by: Flavio Leitner <f...@redhat.com>
> Signed-off-by: Davide Caratti <dcara...@redhat.com>
Applied.
