1 files changed, 32 insertions, 13 deletions

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 12ebde845523..d677b3484d81 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -29,6 +29,7 @@
 #include <linux/hrtimer.h>
 #include <linux/lockdep.h>
 #include <linux/slab.h>
+#include <linux/hashtable.h>
 
 #include <net/net_namespace.h>
 #include <net/sock.h>
@@ -259,37 +260,40 @@ static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
 {
 	struct Qdisc *q;
 
+	if (!qdisc_dev(root))
+		return (root->handle == handle ? root : NULL);
+
 	if (!(root->flags & TCQ_F_BUILTIN) &&
 	    root->handle == handle)
 		return root;
 
-	list_for_each_entry_rcu(q, &root->list, list) {
+	hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle) {
 		if (q->handle == handle)
 			return q;
 	}
 	return NULL;
 }
 
-void qdisc_list_add(struct Qdisc *q)
+void qdisc_hash_add(struct Qdisc *q)
 {
 	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
 		struct Qdisc *root = qdisc_dev(q)->qdisc;
 
 		WARN_ON_ONCE(root == &noop_qdisc);
 		ASSERT_RTNL();
-		list_add_tail_rcu(&q->list, &root->list);
+		hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle);
 	}
 }
-EXPORT_SYMBOL(qdisc_list_add);
+EXPORT_SYMBOL(qdisc_hash_add);
 
-void qdisc_list_del(struct Qdisc *q)
+void qdisc_hash_del(struct Qdisc *q)
 {
 	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
 		ASSERT_RTNL();
-		list_del_rcu(&q->list);
+		hash_del_rcu(&q->hash);
 	}
 }
-EXPORT_SYMBOL(qdisc_list_del);
+EXPORT_SYMBOL(qdisc_hash_del);
 
 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
 {
@@ -998,7 +1002,7 @@ qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
 				goto err_out4;
 		}
 
-		qdisc_list_add(sch);
+		qdisc_hash_add(sch);
 
 		return sch;
 	}
@@ -1431,10 +1435,11 @@ err_out:
 
 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
 			      struct netlink_callback *cb,
-			      int *q_idx_p, int s_q_idx)
+			      int *q_idx_p, int s_q_idx, bool recur)
 {
 	int ret = 0, q_idx = *q_idx_p;
 	struct Qdisc *q;
+	int b;
 
 	if (!root)
 		return 0;
@@ -1449,7 +1454,17 @@ static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
 			goto done;
 		q_idx++;
 	}
-	list_for_each_entry(q, &root->list, list) {
+
+	/* If dumping singletons, there is no qdisc_dev(root) and the singleton
+	 * itself has already been dumped.
+	 *
+	 * If we've already dumped the top-level (ingress) qdisc above and the global
+	 * qdisc hashtable, we don't want to hit it again
+	 */
+	if (!qdisc_dev(root) || !recur)
+		goto out;
+
+	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
 		if (q_idx < s_q_idx) {
 			q_idx++;
 			continue;
@@ -1490,13 +1505,13 @@ static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
 			s_q_idx = 0;
 		q_idx = 0;
 
-		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
+		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx, true) < 0)
 			goto done;
 
 		dev_queue = dev_ingress_queue(dev);
 		if (dev_queue &&
 		    tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
-				       &q_idx, s_q_idx) < 0)
+				       &q_idx, s_q_idx, false) < 0)
 			goto done;
 
 cont:
@@ -1765,6 +1780,7 @@ static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
 			       int *t_p, int s_t)
 {
 	struct Qdisc *q;
+	int b;
 
 	if (!root)
 		return 0;
@@ -1772,7 +1788,10 @@ static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
 	if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
 		return -1;
 
-	list_for_each_entry(q, &root->list, list) {
+	if (!qdisc_dev(root))
+		return 0;
+
+	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
 		if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
 			return -1;
 	}