From: Madalin Bucur <redacted>
Date: Mon, 26 Sep 2011 20:09:16 +0300

flow_cache_flush must not sleep as it can be called in atomic context;
removed the schedule_work as the deferred processing lead to the flow
cache gc never being actually run under heavy network load

Signed-off-by: Madalin Bucur <redacted>

How is this called in an atomic context?  The only caller of
flow_cache_flush() is __xfrm_garbage_collect() which is only invoked
during a NETDEV_DOWN event which ought to be non-atomic.

afinfo->garbage_collect is the only other place __xfrm_garbage_collect
is referenced, and that is completely unused and should thus be deleted
(I'll take care of that in net-next).

If NETDEV_DOWN notifier is in an atomic context, we need to accomodate
or fix that somehow.