pkt_sched: Add 'deactivated' state.

This new state lets dev_deactivate() mark a qdisc as having been
deactivated.

dev_queue_xmit() and ing_filter() check for this bit and do not
try to process the qdisc if the bit is set.

dev_deactivate() polls the qdisc after setting the bit, waiting
for both __QDISC_STATE_RUNNING and __QDISC_STATE_SCHED to clear.

This isn't perfect yet, but subsequent changesets will make it so.
This part is just one piece of the puzzle.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index a7abfda3e447..757ab087adbf 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -27,6 +27,7 @@ enum qdisc_state_t
 {
         __QDISC_STATE_RUNNING,
         __QDISC_STATE_SCHED,
+        __QDISC_STATE_DEACTIVATED,
 };
 
 struct qdisc_size_table {