What is it with my email today, didn't get this one again. On Sat, 28 Nov 2020 01:39:16 +0200 Vladimir Oltean wrote: > 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. Just to avoid breaking the suggestion that seqfiles don't sleep after .start? Hm. I thought BPF slept (or did cond_reshed()) in the middle of seq iteration. We should double check that seqfiles really can't sleep. > > 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.
