selftests: forwarding: generalize bail_on_lldpad from mlxsw

mlxsw selftests often invoke a bail_on_lldpad() helper to make sure LLDPAD
is not running, to prevent conflicts between the QoS configuration applied
through TC or DCB command line tool, and the DCB configuration that LLDPAD
might apply. This helper might be useful to others. Move the function to
lib.sh, and parameterize to make reusable in other contexts.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/drivers/net/mlxsw/qos_headroom.sh

@@ -18,7 +18,6 @@ lib_dir=$(dirname $0)/../../../net/forwarding
 NUM_NETIFS=0
 source $lib_dir/lib.sh
 source $lib_dir/devlink_lib.sh
-source qos_lib.sh
 
 swp=$NETIF_NO_CABLE
 
@@ -371,7 +370,7 @@ test_tc_int_buf()
 	tc qdisc delete dev $swp root
 }
 
-bail_on_lldpad
+bail_on_lldpad "configure DCB" "configure Qdiscs"
 
 trap cleanup EXIT
 setup_wait

tools/testing/selftests/drivers/net/mlxsw/qos_lib.sh

@@ -54,31 +54,3 @@ measure_rate()
 	echo $ir $er
 	return $ret
 }
-
-bail_on_lldpad()
-{
-	if systemctl is-active --quiet lldpad; then
-
-		cat >/dev/stderr <<-EOF
-		WARNING: lldpad is running
-
-			lldpad will likely configure DCB, and this test will
-			configure Qdiscs. mlxsw does not support both at the
-			same time, one of them is arbitrarily going to overwrite
-			the other. That will cause spurious failures (or,
-			unlikely, passes) of this test.
-		EOF
-
-		if [[ -z $ALLOW_LLDPAD ]]; then
-			cat >/dev/stderr <<-EOF
-
-				If you want to run the test anyway, please set
-				an environment variable ALLOW_LLDPAD to a
-				non-empty string.
-			EOF
-			exit 1
-		else
-			return
-		fi
-	fi
-}

tools/testing/selftests/drivers/net/mlxsw/qos_pfc.sh

@@ -79,7 +79,6 @@ lib_dir=$(dirname $0)/../../../net/forwarding
 NUM_NETIFS=6
 source $lib_dir/lib.sh
 source $lib_dir/devlink_lib.sh
-source qos_lib.sh
 
 _1KB=1000
 _100KB=$((100 * _1KB))
@@ -393,7 +392,7 @@ test_qos_pfc()
 	log_test "PFC"
 }
 
-bail_on_lldpad
+bail_on_lldpad "configure DCB" "configure Qdiscs"
 
 trap cleanup EXIT
 setup_prepare

tools/testing/selftests/drivers/net/mlxsw/sch_ets.sh

@@ -5,7 +5,6 @@
 lib_dir=$(dirname $0)/../../../net/forwarding
 source $lib_dir/sch_ets_core.sh
 source $lib_dir/devlink_lib.sh
-source qos_lib.sh
 
 ALL_TESTS="
 	ping_ipv4
@@ -78,5 +77,5 @@ collect_stats()
 	done
 }
 
-bail_on_lldpad
+bail_on_lldpad "configure DCB" "configure Qdiscs"
 ets_run

tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh

@@ -74,7 +74,6 @@ lib_dir=$(dirname $0)/../../../net/forwarding
 source $lib_dir/lib.sh
 source $lib_dir/devlink_lib.sh
 source mlxsw_lib.sh
-source qos_lib.sh
 
 ipaddr()
 {

tools/testing/selftests/drivers/net/mlxsw/sch_red_ets.sh

@@ -166,7 +166,7 @@ ecn_mirror_test()
 	uninstall_qdisc
 }
 
-bail_on_lldpad
+bail_on_lldpad "configure DCB" "configure Qdiscs"
 
 trap cleanup EXIT
 setup_prepare

tools/testing/selftests/drivers/net/mlxsw/sch_red_root.sh

@@ -73,7 +73,7 @@ red_mirror_test()
 	uninstall_qdisc
 }
 
-bail_on_lldpad
+bail_on_lldpad "configure DCB" "configure Qdiscs"
 
 trap cleanup EXIT
 setup_prepare

tools/testing/selftests/drivers/net/mlxsw/sch_tbf_ets.sh

@@ -1,11 +1,9 @@
 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
-source qos_lib.sh
-
 sch_tbf_pre_hook()
 {
-	bail_on_lldpad
+	bail_on_lldpad "configure DCB" "configure Qdiscs"
 }
 
 lib_dir=$(dirname $0)/../../../net/forwarding

tools/testing/selftests/drivers/net/mlxsw/sch_tbf_prio.sh

@@ -1,11 +1,9 @@
 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
-source qos_lib.sh
-
 sch_tbf_pre_hook()
 {
-	bail_on_lldpad
+	bail_on_lldpad "configure DCB" "configure Qdiscs"
 }
 
 lib_dir=$(dirname $0)/../../../net/forwarding

tools/testing/selftests/drivers/net/mlxsw/sch_tbf_root.sh

@@ -1,11 +1,9 @@
 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
-source qos_lib.sh
-
 sch_tbf_pre_hook()
 {
-	bail_on_lldpad
+	bail_on_lldpad "configure DCB" "configure Qdiscs"
 }
 
 lib_dir=$(dirname $0)/../../../net/forwarding

tools/testing/selftests/net/forwarding/lib.sh

@@ -1887,3 +1887,34 @@ mldv1_done_get()
 
 	payload_template_expand_checksum "$hbh$icmpv6" $checksum
 }
+
+bail_on_lldpad()
+{
+	local reason1="$1"; shift
+	local reason2="$1"; shift
+
+	if systemctl is-active --quiet lldpad; then
+
+		cat >/dev/stderr <<-EOF
+		WARNING: lldpad is running
+
+			lldpad will likely $reason1, and this test will
+			$reason2. Both are not supported at the same time,
+			one of them is arbitrarily going to overwrite the
+			other. That will cause spurious failures (or, unlikely,
+			passes) of this test.
+		EOF
+
+		if [[ -z $ALLOW_LLDPAD ]]; then
+			cat >/dev/stderr <<-EOF
+
+				If you want to run the test anyway, please set
+				an environment variable ALLOW_LLDPAD to a
+				non-empty string.
+			EOF
+			exit 1
+		else
+			return
+		fi
+	fi
+}