Merge branch 'net_sched-reduce-the-number-of-qdisc-resets'

Merge branch 'net_sched-reduce-the-number-of-qdisc-resets'

Cong Wang says:

====================
net_sched: reduce the number of qdisc resets

This patchset aims to reduce the number of qdisc resets during
qdisc tear down. Patch 1~3 are preparation for their following
patches, especially patch 2 and patch 3 add a few tracepoints
so that we can observe the whole lifetime of qdisc's. Patch 4
and patch 5 are the ones do the actual work. Please find more
details in each patch description.

Vaclav Zindulka tested this patchset and his large ruleset with
over 13k qdiscs defined got from 22s to 520ms.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>