+static int update_attribute_drop_in(Unit *u, bool runtime, const char *name) {
+ _cleanup_free_ char *buf = NULL;
+ CGroupAttribute *a;
+
+ assert(u);
+ assert(name);
+
+ LIST_FOREACH(by_unit, a, u->cgroup_attributes) {
+ if (!cgroup_attribute_matches(a, NULL, name))
+ continue;
+
+ if (!buf) {
+ buf = strjoin("[", UNIT_VTABLE(u)->exec_section, "]\n"
+ "ControlGroupAttribute=", a->name, " ", a->value, "\n", NULL);
+
+ if (!buf)
+ return -ENOMEM;
+ } else {
+ char *b;
+
+ b = strjoin(buf,
+ "ControlGroupAttribute=", a->name, " ", a->value, "\n", NULL);
+
+ if (!b)
+ return -ENOMEM;
+
+ free(buf);
+ buf = b;
+ }
+ }
+
+ if (buf)
+ return unit_write_drop_in(u, runtime, name, buf);
+ else
+ return unit_remove_drop_in(u, runtime, name);
+}
+