On Tue, Dec 01, 2020 at 11:31:02PM +0100, Tobias Waldekranz wrote: > >> + if (unlikely(!dsa_slave_dev_check(skb->dev))) { > >> + /* Packet is to be injected directly on an upper > >> + * device, e.g. a team/bond, so skip all DSA-port > >> + * specific actions. > >> + */ > >> + netif_rx(skb); > >> + return 0; > > > > netif_rx returns an int code, it seems odd to ignore it. > > This is exactly the same treatment that the return code from > gro_cells_receive gets just a few lines down. They return the same set > of codes (NET_RX_{SUCCESS,DROP}). > > Looking through the source base, there are a few callers that look at > the return value (the overwhelming majority ignore it). Actions vary > from printing warnings (without rate-limit, yikes), setting variables > that are otherwise unused, or bumping a counter (the only reasonable > thing I have seen). > > But looking through enqueue_to_backlog, it seems like there already is a > counter for this that is accessible from /proc/net/softnet_data.
And also, more obviously, in ndo_get_stats64 (ip -s -s link). Ok, I think you can ignore the return value.