[RFC PATCH net-next v2 2/5] net: add phys ID compare helper to test if two IDs are the same

[sfeldma@gmail.com]

From: Scott Feldman <sfeldma@gmail.com>

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
---
 include/linux/netdevice.h |    7 +++++++
 net/switchdev/switchdev.c |    8 ++------
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7be616e1..63090ce 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -766,6 +766,13 @@ struct netdev_phys_item_id {
 	unsigned char id_len;
 };
 
+static inline bool netdev_phys_item_id_same(struct netdev_phys_item_id *a,
+					    struct netdev_phys_item_id *b)
+{
+	return ((a->id_len == b->id_len) &&
+		(memcmp(a->id, b->id, a->id_len) == 0));
+}
+
 typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
 				       struct sk_buff *skb);
 
diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index a5d0f8e..00c67a5 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -791,13 +791,9 @@ static struct net_device *switchdev_get_dev_by_nhs(struct fib_info *fi)
 		if (switchdev_port_attr_get(dev, &attr))
 			return NULL;
 
-		if (nhsel > 0) {
-			if (prev_attr.u.ppid.id_len != attr.u.ppid.id_len)
+		if (nhsel > 0 &&
+		    !netdev_phys_item_id_same(&prev_attr.u.ppid, &attr.u.ppid))
 				return NULL;
-			if (memcmp(prev_attr.u.ppid.id, attr.u.ppid.id,
-				   attr.u.ppid.id_len))
-				return NULL;
-		}
 
 		prev_attr = attr;
 	}
-- 
1.7.10.4