[RFC PATCH net-next 2/3] net: dsa: move switchdev event implementation under the same switch/case statement

[Vladimir Oltean <olteanv@gmail.com>]

We'll need to start listening to SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE
events even for interfaces where dsa_slave_dev_check returns false, so
we need that check inside the switch-case statement for SWITCHDEV_FDB_*.

This movement also avoids two useless allocation / free paths for
switchdev_work, which were difficult to avoid before, due to the code's
structure:
- on the untreated "default event" case.
- on the case where fdb_info->added_by_user is false.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
---
 net/dsa/slave.c | 43 +++++++++++++++++++------------------------
 1 file changed, 19 insertions(+), 24 deletions(-)

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 30db8230e30b..b34da39722c7 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2130,50 +2130,45 @@ static int dsa_slave_switchdev_event(struct notifier_block *unused,
 	struct dsa_port *dp;
 	int err;
 
-	if (event == SWITCHDEV_PORT_ATTR_SET) {
+	switch (event) {
+	case SWITCHDEV_PORT_ATTR_SET:
 		err = switchdev_handle_port_attr_set(dev, ptr,
 						     dsa_slave_dev_check,
 						     dsa_slave_port_attr_set);
 		return notifier_from_errno(err);
-	}
-
-	if (!dsa_slave_dev_check(dev))
-		return NOTIFY_DONE;
-
-	dp = dsa_slave_to_port(dev);
-
-	switchdev_work = kzalloc(sizeof(*switchdev_work), GFP_ATOMIC);
-	if (!switchdev_work)
-		return NOTIFY_BAD;
-
-	INIT_WORK(&switchdev_work->work,
-		  dsa_slave_switchdev_event_work);
-	switchdev_work->ds = dp->ds;
-	switchdev_work->port = dp->index;
-	switchdev_work->event = event;
-
-	switch (event) {
 	case SWITCHDEV_FDB_ADD_TO_DEVICE:
 	case SWITCHDEV_FDB_DEL_TO_DEVICE:
 		fdb_info = ptr;
 
-		if (!fdb_info->added_by_user) {
-			kfree(switchdev_work);
+		if (!dsa_slave_dev_check(dev))
+			return NOTIFY_DONE;
+
+		if (!fdb_info->added_by_user)
 			return NOTIFY_OK;
-		}
+
+		dp = dsa_slave_to_port(dev);
+
+		switchdev_work = kzalloc(sizeof(*switchdev_work), GFP_ATOMIC);
+		if (!switchdev_work)
+			return NOTIFY_BAD;
+
+		INIT_WORK(&switchdev_work->work,
+			  dsa_slave_switchdev_event_work);
+		switchdev_work->ds = dp->ds;
+		switchdev_work->port = dp->index;
+		switchdev_work->event = event;
 
 		ether_addr_copy(switchdev_work->addr,
 				fdb_info->addr);
 		switchdev_work->vid = fdb_info->vid;
 
 		dev_hold(dev);
+		dsa_schedule_work(&switchdev_work->work);
 		break;
 	default:
-		kfree(switchdev_work);
 		return NOTIFY_DONE;
 	}
 
-	dsa_schedule_work(&switchdev_work->work);
 	return NOTIFY_OK;
 }
 
-- 
2.25.1