return unit_get_subtree_mask(u); /* we are the top-level slice */
}
+CGroupMask unit_get_disable_mask(Unit *u) {
+ CGroupContext *c;
+
+ c = unit_get_cgroup_context(u);
+ if (!c)
+ return 0;
+
+ return c->disable_controllers;
+}
+
+CGroupMask unit_get_ancestor_disable_mask(Unit *u) {
+ CGroupMask mask;
+
+ assert(u);
+ mask = unit_get_disable_mask(u);
+
+ /* Returns the mask of controllers which are marked as forcibly
+ * disabled in any ancestor unit or the unit in question. */
+
+ if (UNIT_ISSET(u->slice))
+ mask |= unit_get_ancestor_disable_mask(UNIT_DEREF(u->slice));
+
+ return mask;
+}
+
CGroupMask unit_get_subtree_mask(Unit *u) {
/* Returns the mask of this subtree, meaning of the group
u->cgroup_invalidated_mask == 0;
}
+static bool unit_has_mask_disables_realized(
+ Unit *u,
+ CGroupMask target_mask,
+ CGroupMask enable_mask) {
+
+ assert(u);
+
+ /* Returns true if all controllers which should be disabled are indeed disabled.
+ *
+ * Unlike unit_has_mask_realized, we don't care what was enabled, only that anything we want to remove is
+ * already removed. */
+
+ return !u->cgroup_realized ||
+ (FLAGS_SET(u->cgroup_realized_mask, target_mask & CGROUP_MASK_V1) &&
+ FLAGS_SET(u->cgroup_enabled_mask, enable_mask & CGROUP_MASK_V2));
+}
+
static bool unit_has_mask_enables_realized(
Unit *u,
CGroupMask target_mask,
return 0;
}
+/* Controllers can only be disabled depth-first, from the leaves of the
+ * hierarchy upwards to the unit in question. */
+static int unit_realize_cgroup_now_disable(Unit *u, ManagerState state) {
+ Iterator i;
+ Unit *m;
+ void *v;
+
+ assert(u);
+
+ if (u->type != UNIT_SLICE)
+ return 0;
+
+ HASHMAP_FOREACH_KEY(v, m, u->dependencies[UNIT_BEFORE], i) {
+ CGroupMask target_mask, enable_mask, new_target_mask, new_enable_mask;
+ int r;
+
+ if (UNIT_DEREF(m->slice) != u)
+ continue;
+
+ /* The cgroup for this unit might not actually be fully
+ * realised yet, in which case it isn't holding any controllers
+ * open anyway. */
+ if (!m->cgroup_path)
+ continue;
+
+ /* We must disable those below us first in order to release the
+ * controller. */
+ if (m->type == UNIT_SLICE)
+ (void) unit_realize_cgroup_now_disable(m, state);
+
+ target_mask = unit_get_target_mask(m);
+ enable_mask = unit_get_enable_mask(m);
+
+ /* We can only disable in this direction, don't try to enable
+ * anything. */
+ if (unit_has_mask_disables_realized(m, target_mask, enable_mask))
+ continue;
+
+ new_target_mask = m->cgroup_realized_mask & target_mask;
+ new_enable_mask = m->cgroup_enabled_mask & enable_mask;
+
+ r = unit_create_cgroup(m, new_target_mask, new_enable_mask, state);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
/* Check if necessary controllers and attributes for a unit are in place.
*
if (unit_has_mask_realized(u, target_mask, enable_mask))
return 0;
- /* Enable controllers above us */
+ /* Disable controllers below us, if there are any */
+ r = unit_realize_cgroup_now_disable(u, state);
+ if (r < 0)
+ return r;
+
+ /* Enable controllers above us, if there are any */
if (UNIT_ISSET(u->slice)) {
r = unit_realize_cgroup_now_enable(UNIT_DEREF(u->slice), state);
if (r < 0)