Merge branch 'handle_ing_lightweight'

Daniel Borkmann says:

====================
handle_ing update

These are a couple of cleanups to make ingress a bit more lightweight.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -1655,7 +1655,11 @@ struct net_device {
 	rx_handler_func_t __rcu	*rx_handler;
 	void __rcu		*rx_handler_data;
 
+#if CONFIG_NET_CLS_ACT
+	struct tcf_proto __rcu  *ingress_cl_list;
+#endif
 	struct netdev_queue __rcu *ingress_queue;
+
 	unsigned char		broadcast[MAX_ADDR_LEN];
 #ifdef CONFIG_RFS_ACCEL
 	struct cpu_rmap		*rx_cpu_rmap;

net/core/dev.c

@@ -3521,49 +3521,41 @@ EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
 #endif
 
 #ifdef CONFIG_NET_CLS_ACT
-/* TODO: Maybe we should just force sch_ingress to be compiled in
- * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
- * a compare and 2 stores extra right now if we dont have it on
- * but have CONFIG_NET_CLS_ACT
- * NOTE: This doesn't stop any functionality; if you dont have
- * the ingress scheduler, you just can't add policies on ingress.
- *
- */
-static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
-{
-	int result = TC_ACT_OK;
-	struct Qdisc *q;
-
-	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
-
-	q = rcu_dereference(rxq->qdisc);
-	if (q != &noop_qdisc) {
-		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
-			result = qdisc_enqueue_root(skb, q);
-	}
-
-	return result;
-}
-
 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
 					 struct packet_type **pt_prev,
 					 int *ret, struct net_device *orig_dev)
 {
-	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
+	struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
+	struct tcf_result cl_res;
 
-	if (!rxq || rcu_access_pointer(rxq->qdisc) == &noop_qdisc)
+	/* If there's at least one ingress present somewhere (so
+	 * we get here via enabled static key), remaining devices
+	 * that are not configured with an ingress qdisc will bail
+	 * out here.
+	 */
+	if (!cl)
 		return skb;
-
 	if (*pt_prev) {
 		*ret = deliver_skb(skb, *pt_prev, orig_dev);
 		*pt_prev = NULL;
 	}
 
-	switch (ing_filter(skb, rxq)) {
+	qdisc_bstats_update_cpu(cl->q, skb);
+	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
+
+	switch (tc_classify(skb, cl, &cl_res)) {
+	case TC_ACT_OK:
+	case TC_ACT_RECLASSIFY:
+		skb->tc_index = TC_H_MIN(cl_res.classid);
+		break;
 	case TC_ACT_SHOT:
+		qdisc_qstats_drop_cpu(cl->q);
 	case TC_ACT_STOLEN:
+	case TC_ACT_QUEUED:
 		kfree_skb(skb);
 		return NULL;
+	default:
+		break;
 	}
 
 	return skb;

net/sched/sch_ingress.c

@@ -12,16 +12,10 @@
 #include <linux/list.h>
 #include <linux/skbuff.h>
 #include <linux/rtnetlink.h>
+
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
 
-
-struct ingress_qdisc_data {
-	struct tcf_proto __rcu	*filter_list;
-};
-
-/* ------------------------- Class/flow operations ------------------------- */
-
 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
 {
 	return NULL;
@@ -49,45 +43,11 @@ static void ingress_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 static struct tcf_proto __rcu **ingress_find_tcf(struct Qdisc *sch,
 						 unsigned long cl)
 {
-	struct ingress_qdisc_data *p = qdisc_priv(sch);
-
-	return &p->filter_list;
-}
-
-/* --------------------------- Qdisc operations ---------------------------- */
+	struct net_device *dev = qdisc_dev(sch);
 
-static int ingress_enqueue(struct sk_buff *skb, struct Qdisc *sch)
-{
-	struct ingress_qdisc_data *p = qdisc_priv(sch);
-	struct tcf_result res;
-	struct tcf_proto *fl = rcu_dereference_bh(p->filter_list);
-	int result;
-
-	result = tc_classify(skb, fl, &res);
-
-	qdisc_bstats_update_cpu(sch, skb);
-	switch (result) {
-	case TC_ACT_SHOT:
-		result = TC_ACT_SHOT;
-		qdisc_qstats_drop_cpu(sch);
-		break;
-	case TC_ACT_STOLEN:
-	case TC_ACT_QUEUED:
-		result = TC_ACT_STOLEN;
-		break;
-	case TC_ACT_RECLASSIFY:
-	case TC_ACT_OK:
-		skb->tc_index = TC_H_MIN(res.classid);
-	default:
-		result = TC_ACT_OK;
-		break;
-	}
-
-	return result;
+	return &dev->ingress_cl_list;
 }
 
-/* ------------------------------------------------------------- */
-
 static int ingress_init(struct Qdisc *sch, struct nlattr *opt)
 {
 	net_inc_ingress_queue();
@@ -98,9 +58,9 @@ static int ingress_init(struct Qdisc *sch, struct nlattr *opt)
 
 static void ingress_destroy(struct Qdisc *sch)
 {
-	struct ingress_qdisc_data *p = qdisc_priv(sch);
+	struct net_device *dev = qdisc_dev(sch);
 
-	tcf_destroy_chain(&p->filter_list);
+	tcf_destroy_chain(&dev->ingress_cl_list);
 	net_dec_ingress_queue();
 }
 
@@ -111,6 +71,7 @@ static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 	nest = nla_nest_start(skb, TCA_OPTIONS);
 	if (nest == NULL)
 		goto nla_put_failure;
+
 	return nla_nest_end(skb, nest);
 
 nla_put_failure:
@@ -131,8 +92,6 @@ static const struct Qdisc_class_ops ingress_class_ops = {
 static struct Qdisc_ops ingress_qdisc_ops __read_mostly = {
 	.cl_ops		=	&ingress_class_ops,
 	.id		=	"ingress",
-	.priv_size	=	sizeof(struct ingress_qdisc_data),
-	.enqueue	=	ingress_enqueue,
 	.init		=	ingress_init,
 	.destroy	=	ingress_destroy,
 	.dump		=	ingress_dump,
@@ -149,6 +108,7 @@ static void __exit ingress_module_exit(void)
 	unregister_qdisc(&ingress_qdisc_ops);
 }
 
-module_init(ingress_module_init)
-module_exit(ingress_module_exit)
+module_init(ingress_module_init);
+module_exit(ingress_module_exit);
+
 MODULE_LICENSE("GPL");