net: Define accessors to manipulate QDISC_STATE_RUNNING

Define three helpers to manipulate QDISC_STATE_RUNNIG flag, that a
second patch will move on another location.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 03ca5d8..9707dae 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -76,6 +76,21 @@
 	struct rcu_head     rcu_head;
 };
 
+static inline bool qdisc_is_running(struct Qdisc *qdisc)
+{
+	return test_bit(__QDISC_STATE_RUNNING, &qdisc->state);
+}
+
+static inline bool qdisc_run_begin(struct Qdisc *qdisc)
+{
+	return !test_and_set_bit(__QDISC_STATE_RUNNING, &qdisc->state);
+}
+
+static inline void qdisc_run_end(struct Qdisc *qdisc)
+{
+	clear_bit(__QDISC_STATE_RUNNING, &qdisc->state);
+}
+
 struct Qdisc_class_ops {
 	/* Child qdisc manipulation */
 	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);