#!/bin/bash# SPDX-License-Identifier: GPL-2.0 readonly FLUSH_PATH="/sys/class/net/${dev}/gro_flush_timeout"readonly IRQ_PATH="/sys/class/net/${dev}/napi_defer_hard_irqs"readonly FLUSH_TIMEOUT="$(< ${FLUSH_PATH})"readonly HARD_IRQS="$(< ${IRQ_PATH})"readonly server_ns=$(mktemp -u server-XXXXXXXX)readonly client_ns=$(mktemp -u client-XXXXXXXX) netdev_check_for_carrier() {	local -r dev="$1" 	for i in {1..5}; do		carrier="$(cat /sys/class/net/${dev}/carrier)"		if [[ "${carrier}" -ne 1 ]] ; then			echo "carrier not ready yet..." >&2			sleep 1		else			echo "carrier ready" >&2			break		fi	done	echo "${carrier}"} # Assumes that there is no existing ipvlan device on the physical devicesetup_loopback_environment() {	local dev="$1" 	# Fail hard if cannot turn on loopback mode for current NIC	ethtool -K "${dev}" loopback on || exit 1	sleep 1 	# Check for the carrier	carrier=$(netdev_check_for_carrier ${dev})	if [[ "${carrier}" -ne 1 ]] ; then		echo "setup_loopback_environment failed"		exit 1	fi} setup_macvlan_ns(){	local -r link_dev="$1"	local -r ns_name="$2"	local -r ns_dev="$3"	local -r ns_mac="$4"	local -r addr="$5" 	ip link add link "${link_dev}" dev "${ns_dev}" \		address "${ns_mac}" type macvlan	exit_code=$?	if [[ "${exit_code}" -ne 0 ]]; then		echo "setup_macvlan_ns failed"		exit $exit_code	fi 	[[ -e /var/run/netns/"${ns_name}" ]] || ip netns add "${ns_name}"	ip link set dev "${ns_dev}" netns "${ns_name}"	ip -netns "${ns_name}" link set dev "${ns_dev}" up	if [[ -n "${addr}" ]]; then		ip -netns "${ns_name}" addr add dev "${ns_dev}" "${addr}"	fi 	sleep 1} cleanup_macvlan_ns(){	while (( $# >= 2 )); do		ns_name="$1"		ns_dev="$2"		ip -netns "${ns_name}" link del dev "${ns_dev}"		ip netns del "${ns_name}"		shift 2	done} cleanup_loopback(){	local -r dev="$1" 	ethtool -K "${dev}" loopback off	sleep 1 	# Check for the carrier	carrier=$(netdev_check_for_carrier ${dev})	if [[ "${carrier}" -ne 1 ]] ; then		echo "setup_loopback_environment failed"		exit 1	fi} setup_interrupt() {	# Use timer on  host to trigger the network stack	# Also disable device interrupt to not depend on NIC interrupt	# Reduce test flakiness caused by unexpected interrupts	echo 100000 >"${FLUSH_PATH}"	echo 50 >"${IRQ_PATH}"} setup_ns() {	# Set up server_ns namespace and client_ns namespace	setup_macvlan_ns "${dev}" ${server_ns} server "${SERVER_MAC}"	setup_macvlan_ns "${dev}" ${client_ns} client "${CLIENT_MAC}"} cleanup_ns() {	cleanup_macvlan_ns ${server_ns} server ${client_ns} client} setup() {	setup_loopback_environment "${dev}"	setup_interrupt} cleanup() {	cleanup_loopback "${dev}" 	echo "${FLUSH_TIMEOUT}" >"${FLUSH_PATH}"	echo "${HARD_IRQS}" >"${IRQ_PATH}"}