Subject: Re: [PATCH net v2 2/2] selftests: pmtu: add explicit tests for PMTU exceptions cleanup

From: Stefano Brivio <[email-masked]>
Date: Mon, 25 Feb 2019 12:35:11 +0100

Just three minor details, feel free to ignore:

On Mon, 25 Feb 2019 12:13:46 +0100
Paolo Abeni <[email-masked]> wrote:

> @@ -1006,6 +1017,60 @@ test_pmtu_vti6_link_change_mtu() {
>  	return ${fail}
>  }
>  
> +chk_command() {

All the other functions checking something are called 'check_*'.

> +	cmd=${1}
> +
> +	if ! which ${cmd} > /dev/null 2>&1; then
> +		err "  missing required command: '${cmd}'"
> +		return 1
> +	fi
> +	return 0
> +}
> +
> +test_cleanup_vxlanX_exception() {
> +	outer="${1}"
> +	encap="vxlan"
> +	ll_mtu=4000
> +
> +	chk_command taskset || return 2
> +	chk_command timeout || return 2
> +	cpu_list=$(grep -m 2 processor /proc/cpuinfo | cut -d ' ' -f 2)
> +
> +	setup namespaces routing ${encap}${outer} || return 2
> +	trace "${ns_a}" ${encap}_a   "${ns_b}"  ${encap}_b \
> +	      "${ns_a}" veth_A-R1    "${ns_r1}" veth_R1-A \
> +	      "${ns_b}" veth_B-R1    "${ns_r1}" veth_R1-B
> +
> +	# Create route exception by exceeding link layer MTU
> +	mtu "${ns_a}"  veth_A-R1 $((${ll_mtu} + 1000))
> +	mtu "${ns_r1}" veth_R1-A $((${ll_mtu} + 1000))
> +	mtu "${ns_b}"  veth_B-R1 ${ll_mtu}
> +	mtu "${ns_r1}" veth_R1-B ${ll_mtu}
> +
> +	mtu "${ns_a}" ${encap}_a $((${ll_mtu} + 1000))
> +	mtu "${ns_b}" ${encap}_b $((${ll_mtu} + 1000))
> +
> +	# Fill exception cache for multiple CPUs (2)
> +	# we can always use inner IPv4 for that
> +	for cpu in ${cpu_list}; do
> +		taskset --cpu-list ${cpu} ${ns_a} ping -q -M want -i 0.1 -w 1 -s $((${ll_mtu} + 500)) ${tunnel4_b_addr} > /dev/null
> +	done
> +
> +	if ! timeout 1 ${ns_a} ip link del dev veth_A-R1; then
> +		err "  can't delete veth device in a timely manner, PMTU dst likely leaked"
> +		return 1
> +	fi
> +	return 0

No need for explicit return 0.

> +}
> +
> +test_pmtu_ipv6_exception_cleanup() {
> +	test_cleanup_vxlanX_exception 6 vxlan
> +}
> +
> +test_pmtu_ipv4_exception_cleanup() {
> +	test_cleanup_vxlanX_exception 4 vxlan

This function now takes just one argument.

-- 
Stefano