Update some helpers so that they are capable to run commands on
different targets than the local one. This patch makes the necesasy
modification for those helpers / sections of code which are needed for
the ethtool_rmon.sh test that will be converted in the next patches.

For example, mac_addr_prepare() and mac_addr_restore() used when
STABLE_MAC_ADDRS=yes need to ensure stable MAC addresses on interfaces
located even in other namespaces. In order to do that, append the 'ip
link' commands with a 'run_on $dev' tag.

The same run_on is necessary also when verifying if all the interfaces
listed in NETIFS are indeed available.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
---
Changes in v5:
- none
Changes in v4:
- split some lines to 80 chars
Changes in v3:
- added some more double quotes
Changes in v2:
- patch is new

 tools/testing/selftests/net/forwarding/lib.sh | 19 ++++++++++++-------
 tools/testing/selftests/net/lib.sh            |  3 ++-
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 83249aafa669..d8cc4c64148d 100644
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -546,10 +546,11 @@ mac_addr_prepare()
 		dev=${NETIFS[p$i]}
 		new_addr=$(printf "00:01:02:03:04:%02x" $i)
 
-		MAC_ADDR_ORIG["$dev"]=$(ip -j link show dev $dev | jq -e '.[].address')
+		MAC_ADDR_ORIG["$dev"]=$(run_on "$dev" \
+			ip -j link show dev "$dev" | jq -e '.[].address')
 		# Strip quotes
 		MAC_ADDR_ORIG["$dev"]=${MAC_ADDR_ORIG["$dev"]//\"/}
-		ip link set dev $dev address $new_addr
+		run_on "$dev" ip link set dev "$dev" address $new_addr
 	done
 }
 
@@ -559,7 +560,8 @@ mac_addr_restore()
 
 	for ((i = 1; i <= NUM_NETIFS; ++i)); do
 		dev=${NETIFS[p$i]}
-		ip link set dev $dev address ${MAC_ADDR_ORIG["$dev"]}
+		run_on "$dev" \
+			ip link set dev "$dev" address ${MAC_ADDR_ORIG["$dev"]}
 	done
 }
 
@@ -572,7 +574,9 @@ if [[ "$STABLE_MAC_ADDRS" = "yes" ]]; then
 fi
 
 for ((i = 1; i <= NUM_NETIFS; ++i)); do
-	ip link show dev ${NETIFS[p$i]} &> /dev/null
+	int="${NETIFS[p$i]}"
+
+	run_on "$int" ip link show dev "$int" &> /dev/null
 	if [[ $? -ne 0 ]]; then
 		echo "SKIP: could not find all required interfaces"
 		exit $ksft_skip
@@ -655,7 +659,7 @@ setup_wait_dev_with_timeout()
 	local i
 
 	for ((i = 1; i <= $max_iterations; ++i)); do
-		ip link show dev $dev up \
+		run_on "$dev" ip link show dev "$dev" up \
 			| grep 'state UP' &> /dev/null
 		if [[ $? -ne 0 ]]; then
 			sleep 1
@@ -960,12 +964,13 @@ ethtool_std_stats_get()
 	local src=$1; shift
 
 	if [[ "$grp" == "pause" ]]; then
-		ethtool -I --json -a "$dev" --src "$src" | \
+		run_on "$dev" ethtool -I --json -a "$dev" --src "$src" | \
 			jq --arg name "$name" '.[].statistics[$name]'
 		return
 	fi
 
-	ethtool --json -S "$dev" --groups "$grp" -- --src "$src" | \
+	run_on "$dev" \
+		ethtool --json -S "$dev" --groups "$grp" -- --src "$src" | \
 		jq --arg grp "$grp" --arg name "$name" '.[][$grp][$name]'
 }
 
diff --git a/tools/testing/selftests/net/lib.sh b/tools/testing/selftests/net/lib.sh
index 3f79bf1ec977..e915386daf1b 100644
--- a/tools/testing/selftests/net/lib.sh
+++ b/tools/testing/selftests/net/lib.sh
@@ -514,7 +514,8 @@ mac_get()
 {
 	local if_name=$1
 
-	ip -j link show dev $if_name | jq -r '.[]["address"]'
+	run_on "$if_name" \
+		ip -j link show dev "$if_name" | jq -r '.[]["address"]'
 }
 
 kill_process()
-- 
2.25.1