On Fri, 16 Oct 2020 18:56:45 +0300 Vladimir Oltean wrote: > > 3. "Manually" unsharing in dsa_slave_xmit(), reserving enough tailroom > > for the tail tag (and ETH_ZLEN?). Would moving the "else" clause from > > ksz_common_xmit() to dsa_slave_xmit() do the job correctly? > > I was thinking about something like that, indeed. DSA knows everything > about the tagger: its overhead, whether it's a tail tag or not. The xmit > callback of the tagger should only be there to populate the tag where it > needs to be. But reallocation, padding, etc etc, should all be dealt > with by the common DSA xmit procedure. We want the taggers to be simple > and reuse as much logic as possible, not to be bloated.
FWIW if you want to avoid the reallocs you may want to set needed_tailroom on the netdev.
