From b5e489003abcff4b65088d49fce78dcb3cc1ae06 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 14 Feb 2025 14:46:01 -0800 Subject: [PATCH] netdev: clarify GSO vs csum in qstats Could be just me, but I had to pause and double check that the Tx csum counter in qstat should include GSO'd packets. GSO pretty much implies csum so one could possibly interpret the csum counter as pure csum offload. But the counters are based on virtio: [tx_needs_csum] The number of packets which require checksum calculation by the device. [rx_needs_csum] The number of packets with VIRTIO_NET_HDR_F_NEEDS_CSUM. and VIRTIO_NET_HDR_F_NEEDS_CSUM gets set on GSO packets virtio sends. Clarify this in the spec to avoid any confusion. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20250214224601.2271201-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/netdev.yaml | 2 ++ 1 file changed, 2 insertions(+) diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml index 85402a2e289c..766b82005d18 100644 --- a/Documentation/netlink/specs/netdev.yaml +++ b/Documentation/netlink/specs/netdev.yaml @@ -467,6 +467,8 @@ attribute-sets: name: tx-needs-csum doc: | Number of packets that required the device to calculate the checksum. + This counter includes the number of GSO wire packets for which device + calculated the L4 checksum. type: uint - name: tx-hw-gso-packets