On Tue, 2018-02-27 at 07:09 -0800, Eric Dumazet wrote:

Note that for this one, it seems we also could perform stats updates in
BH context, since skb is queued via defer_bh()

But simplicity wins I guess.

Thinking more about this, I am not sure we have any guarantee that TX
and RX can not run on multiple cpus.

Using an unique syncp is not going to be safe, even if we make lockdep
happy enough with the local_irq save/restore.