netifd: disable receive packet steering for DSA slave devices

It is already handled on the master device. Doing it twice reduces
performance

Signed-off-by: Felix Fietkau <nbd@nbd.name>

package/network/config/netifd/files/etc/hotplug.d/net/20-smp-packet-steering

@@ -52,11 +52,16 @@ for dev in /sys/class/net/*; do
 	irq_cpu="$(find_irq_cpu "$device")"
 	irq_cpu_mask="$((1 << $irq_cpu))"
 
-	for q in ${dev}/queues/rx-*; do
-		set_hex_val "$q/rps_cpus" "$PROC_MASK"
-	done
-
 	for q in ${dev}/queues/tx-*; do
 		set_hex_val "$q/xps_cpus" "$PROC_MASK"
 	done
+
+	# ignore dsa slave ports for RPS
+	subsys="$(readlink "${dev}/device/subsystem")"
+	subsys="$(basename "$subsys")"
+	[ "$subsys" = "mdio_bus" ] && continue
+
+	for q in ${dev}/queues/rx-*; do
+		set_hex_val "$q/rps_cpus" "$PROC_MASK"
+	done
 done