From: Eric Dumazet <redacted>
Date: Fri, 06 Jan 2017 12:13:23 -0800
Well, there are cases where RTNL is quite contended, but supervisions
like to get /proc/net/devices or various sysfs attributes
(netstat_show() can be called very very often
for /sys/class/net/*/statistics/*) in a reasonable amount of time.
I fear that such a change will add drifts, when devices are constantly
added/removed.
It stands to reason that RTNETLINK could use pure RCU locking for
device and stat dumps, and frankly that would make their usage and
overhead superior to poking files over and over.