net_sched: move dev_graft_qdisc() to sch_generic.c
It will be used in a following patch by the multiqueue qdisc.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index a91f079..e7c47ce 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -623,6 +623,31 @@
}
EXPORT_SYMBOL(qdisc_destroy);
+/* Attach toplevel qdisc to device queue. */
+struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
+ struct Qdisc *qdisc)
+{
+ struct Qdisc *oqdisc = dev_queue->qdisc_sleeping;
+ spinlock_t *root_lock;
+
+ root_lock = qdisc_lock(oqdisc);
+ spin_lock_bh(root_lock);
+
+ /* Prune old scheduler */
+ if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1)
+ qdisc_reset(oqdisc);
+
+ /* ... and graft new one */
+ if (qdisc == NULL)
+ qdisc = &noop_qdisc;
+ dev_queue->qdisc_sleeping = qdisc;
+ rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc);
+
+ spin_unlock_bh(root_lock);
+
+ return oqdisc;
+}
+
static void attach_one_default_qdisc(struct net_device *dev,
struct netdev_queue *dev_queue,
void *_unused)