net: thunderbolt: Count delivered packets in rx_packets and rx_bytes

tbnet_poll() increments rx_packets once per received frame because that is
the NAPI work unit, and then adds the same number to stats.rx_packets. An
skb is handed to the stack only when the last frame of a packet arrives,
so once the MTU exceeds TBNET_MAX_PAYLOAD_SIZE the statistic reports
frames. tx_packets is bumped once per skb, so the two ends of a link
disagree: at MTU 65330 the receiver reports 16 times the packets its
sender sent.

rx_bytes has the matching problem: frames of a packet that is later
dropped mid-assembly are already accounted, so it does not correspond to
rx_packets as documented. Account for both where the packet is completed,
and leave the NAPI work counter alone.

Fixes: e69b6c02b4 ("net: Add support for networking over Thunderbolt cable")
Signed-off-by: Fan Ye <fy15309206903@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Mika Westerberg <westeri@kernel.org>
Link: https://patch.msgid.link/20260815-tbnet-rx-stats-v1-1-8da375c2cd09@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Fan Ye 2026-08-15 10:21:52 +00:00 • committed by Jakub Kicinski
commit c5ae83ee02