2 files changed, 32 insertions, 6 deletions

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 625cf185c489..fe2ca02a1979 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -176,6 +176,23 @@ static void rt_nexthop_free(struct rtable __rcu **rtp)
 	dst_free(&rt->dst);
 }
 
+static void rt_nexthop_free_cpus(struct rtable __rcu * __percpu *rtp)
+{
+	int cpu;
+
+	if (!rtp)
+		return;
+
+	for_each_possible_cpu(cpu) {
+		struct rtable *rt;
+
+		rt = rcu_dereference_protected(*per_cpu_ptr(rtp, cpu), 1);
+		if (rt)
+			dst_free(&rt->dst);
+	}
+	free_percpu(rtp);
+}
+
 /* Release a nexthop info record */
 static void free_fib_info_rcu(struct rcu_head *head)
 {
@@ -186,7 +203,7 @@ static void free_fib_info_rcu(struct rcu_head *head)
 			dev_put(nexthop_nh->nh_dev);
 		if (nexthop_nh->nh_exceptions)
 			free_nh_exceptions(nexthop_nh);
-		rt_nexthop_free(&nexthop_nh->nh_rth_output);
+		rt_nexthop_free_cpus(nexthop_nh->nh_pcpu_rth_output);
 		rt_nexthop_free(&nexthop_nh->nh_rth_input);
 	} endfor_nexthops(fi);
 
@@ -817,6 +834,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 	fi->fib_nhs = nhs;
 	change_nexthops(fi) {
 		nexthop_nh->nh_parent = fi;
+		nexthop_nh->nh_pcpu_rth_output = alloc_percpu(struct rtable __rcu *);
 	} endfor_nexthops(fi)
 
 	if (cfg->fc_mx) {
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 2bd107477469..4f6276ce0af3 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1206,11 +1206,15 @@ static inline void rt_free(struct rtable *rt)
 
 static void rt_cache_route(struct fib_nh *nh, struct rtable *rt)
 {
-	struct rtable *orig, *prev, **p = (struct rtable **)&nh->nh_rth_output;
+	struct rtable *orig, *prev, **p;
 
-	if (rt_is_input_route(rt))
+	if (rt_is_input_route(rt)) {
 		p = (struct rtable **)&nh->nh_rth_input;
-
+	} else {
+		if (!nh->nh_pcpu_rth_output)
+			goto nocache;
+		p = (struct rtable **)__this_cpu_ptr(nh->nh_pcpu_rth_output);
+	}
 	orig = *p;
 
 	prev = cmpxchg(p, orig, rt);
@@ -1223,6 +1227,7 @@ static void rt_cache_route(struct fib_nh *nh, struct rtable *rt)
 		 * unsuccessful at storing this route into the cache
 		 * we really need to set it.
 		 */
+nocache:
 		rt->dst.flags |= DST_NOCACHE;
 	}
 }
@@ -1749,8 +1754,11 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 	fnhe = NULL;
 	if (fi) {
 		fnhe = find_exception(&FIB_RES_NH(*res), fl4->daddr);
-		if (!fnhe) {
-			rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_output);
+		if (!fnhe && FIB_RES_NH(*res).nh_pcpu_rth_output) {
+			struct rtable __rcu **prth;
+
+			prth = __this_cpu_ptr(FIB_RES_NH(*res).nh_pcpu_rth_output);
+			rth = rcu_dereference(*prth);
 			if (rt_cache_valid(rth)) {
 				dst_hold(&rth->dst);
 				return rth;