net: convert rps_needed and rfs_needed to new static branch api

We prefer static_branch_unlikely() over static_key_false() these days.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tun.c

@@ -1042,7 +1042,7 @@ static int tun_net_close(struct net_device *dev)
 static void tun_automq_xmit(struct tun_struct *tun, struct sk_buff *skb)
 {
 #ifdef CONFIG_RPS
-	if (tun->numqueues == 1 && static_key_false(&rps_needed)) {
+	if (tun->numqueues == 1 && static_branch_unlikely(&rps_needed)) {
 		/* Select queue was not called for the skbuff, so we extract the
 		 * RPS hash and save it into the flow_table here.
 		 */

include/linux/netdevice.h

@@ -194,8 +194,8 @@ struct net_device_stats {
 
 #ifdef CONFIG_RPS
 #include <linux/static_key.h>
-extern struct static_key rps_needed;
-extern struct static_key rfs_needed;
+extern struct static_key_false rps_needed;
+extern struct static_key_false rfs_needed;
 #endif
 
 struct neighbour;

include/net/sock.h

@@ -966,7 +966,7 @@ static inline void sock_rps_record_flow_hash(__u32 hash)
 static inline void sock_rps_record_flow(const struct sock *sk)
 {
 #ifdef CONFIG_RPS
-	if (static_key_false(&rfs_needed)) {
+	if (static_branch_unlikely(&rfs_needed)) {
 		/* Reading sk->sk_rxhash might incur an expensive cache line
 		 * miss.
 		 *

net/core/dev.c

@@ -3982,9 +3982,9 @@ EXPORT_SYMBOL(rps_sock_flow_table);
 u32 rps_cpu_mask __read_mostly;
 EXPORT_SYMBOL(rps_cpu_mask);
 
-struct static_key rps_needed __read_mostly;
+struct static_key_false rps_needed __read_mostly;
 EXPORT_SYMBOL(rps_needed);
-struct static_key rfs_needed __read_mostly;
+struct static_key_false rfs_needed __read_mostly;
 EXPORT_SYMBOL(rfs_needed);
 
 static struct rps_dev_flow *
@@ -4510,7 +4510,7 @@ static int netif_rx_internal(struct sk_buff *skb)
 	}
 
 #ifdef CONFIG_RPS
-	if (static_key_false(&rps_needed)) {
+	if (static_branch_unlikely(&rps_needed)) {
 		struct rps_dev_flow voidflow, *rflow = &voidflow;
 		int cpu;
 
@@ -5179,7 +5179,7 @@ static int netif_receive_skb_internal(struct sk_buff *skb)
 
 	rcu_read_lock();
 #ifdef CONFIG_RPS
-	if (static_key_false(&rps_needed)) {
+	if (static_branch_unlikely(&rps_needed)) {
 		struct rps_dev_flow voidflow, *rflow = &voidflow;
 		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
 
@@ -5227,7 +5227,7 @@ static void netif_receive_skb_list_internal(struct list_head *head)
 
 	rcu_read_lock();
 #ifdef CONFIG_RPS
-	if (static_key_false(&rps_needed)) {
+	if (static_branch_unlikely(&rps_needed)) {
 		list_for_each_entry_safe(skb, next, head, list) {
 			struct rps_dev_flow voidflow, *rflow = &voidflow;
 			int cpu = get_rps_cpu(skb->dev, skb, &rflow);

net/core/net-sysfs.c

@@ -754,9 +754,9 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
 	rcu_assign_pointer(queue->rps_map, map);
 
 	if (map)
-		static_key_slow_inc(&rps_needed);
+		static_branch_inc(&rps_needed);
 	if (old_map)
-		static_key_slow_dec(&rps_needed);
+		static_branch_dec(&rps_needed);
 
 	mutex_unlock(&rps_map_mutex);
 

net/core/sysctl_net_core.c

@@ -95,12 +95,12 @@ static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
 		if (sock_table != orig_sock_table) {
 			rcu_assign_pointer(rps_sock_flow_table, sock_table);
 			if (sock_table) {
-				static_key_slow_inc(&rps_needed);
-				static_key_slow_inc(&rfs_needed);
+				static_branch_inc(&rps_needed);
+				static_branch_inc(&rfs_needed);
 			}
 			if (orig_sock_table) {
-				static_key_slow_dec(&rps_needed);
-				static_key_slow_dec(&rfs_needed);
+				static_branch_dec(&rps_needed);
+				static_branch_dec(&rfs_needed);
 				synchronize_rcu();
 				vfree(orig_sock_table);
 			}