On Sat, Nov 28, 2020 at 12:30:48AM +0100, Andrew Lunn wrote: > > If there is a better alternative I'm all ears but having /proc and > > ifconfig return zeros for error counts while ip link doesn't will lead > > to too much confusion IMO. While delayed update of stats is a fact of > > life for _years_ now (hence it was backed into the ethtool -C API). > > How about dev_seq_start() issues a netdev notifier chain event, asking > devices which care to update their cached rtnl_link_stats64 counters. > They can decide if their cache is too old, and do a blocking read for > new values. > > Once the notifier has completed, dev_seq_start() can then > rcu_read_lock() and do the actual collection of stats from the drivers > non-blocking. That sounds smart. I can try to prototype that and see how well it works, or do you want to?