From: Jarek Poplawski <redacted>
Date: Fri, 22 Aug 2008 09:27:30 +0000

pkt_sched: Fix qdisc list locking

Since some qdiscs call qdisc_tree_decrease_qlen() (so qdisc_lookup())
without rtnl_lock(), adding and deleting from a qdisc list needs
additional locking. This patch adds global spinlock qdisc_list_lock
and wrapper functions for modifying the list. It is considered as a
temporary solution until hfsc_dequeue(), netem_dequeue() and
tbf_dequeue() (or qdisc_tree_decrease_qlen()) are redone.

With feedback from Herbert Xu and David S. Miller.

Signed-off-by: Jarek Poplawski <redacted>

Looks good Jarek, thanks!

Since these requeue failure cases are slow paths, this shouldn't have
any performance impact either.

I'll apply this, thanks!