Add debug logging

tools/testing/selftests/net/mptcp/diag.sh

@@ -54,6 +54,9 @@ __chk_nr()
 
 	nr=$(eval $command)
 
+	echo "chk_nr evaluation output:"
+	echo "$nr"
+
 	mptcp_lib_print_title "$msg"
 	if [ "$nr" != "$expected" ]; then
 		if [ "$nr" = "$skip" ] && ! mptcp_lib_expect_all_features; then
@@ -85,9 +88,10 @@ __chk_msk_nr()
 	__chk_nr "ss --info --numeric --memory --no-header --mptcp --net=$ns | $condition" "$@"
 }
 
+# Count the amount of "token:" appearing in the ss output
 chk_msk_nr()
 {
-	__chk_msk_nr "grep -c token:" "$@"
+	__chk_msk_nr "grep --count token:" "$@"
 }
 
 chk_listener_nr()
@@ -134,11 +138,13 @@ wait_msk_nr()
 	fi
 }
 
+# Count the amount of "fallback" appearing in the ss output
 chk_msk_fallback_nr()
 {
 	__chk_msk_nr "grep -c fallback" "$@"
 }
 
+# Count the amount of "remote_key" appearing in the ss output
 chk_msk_remote_key_nr()
 {
 	__chk_msk_nr "grep -c remote_key" "$@"