}
static CGroupControllerMask unit_get_members_mask(Unit *u) {
- CGroupControllerMask mask = 0;
- Unit *m;
- Iterator i;
-
assert(u);
-
- SET_FOREACH(m, u->dependencies[UNIT_BEFORE], i) {
-
- if (UNIT_DEREF(m->slice) != u)
- continue;
-
- mask |= unit_get_cgroup_mask(m) | unit_get_members_mask(m);
- }
-
- return mask;
+ return u->cgroup_members_mask;
}
static CGroupControllerMask unit_get_siblings_mask(Unit *u) {
(CGROUP_CPU|CGROUP_BLKIO|CGROUP_CPUACCT);
}
+static CGroupControllerMask unit_get_target_mask(Unit *u) {
+ CGroupControllerMask mask;
+
+ mask = unit_get_cgroup_mask(u) | unit_get_members_mask(u) | unit_get_siblings_mask(u);
+ mask &= u->manager->cgroup_supported;
+
+ return mask;
+}
+
+/* Recurse from a unit up through its containing slices, propagating
+ * mask bits upward. A unit is also member of itself. */
+void unit_update_member_masks(Unit *u) {
+ u->cgroup_members_mask |= unit_get_cgroup_mask(u);
+ if (UNIT_ISSET(u->slice)) {
+ Unit *s = UNIT_DEREF(u->slice);
+ s->cgroup_members_mask |= u->cgroup_members_mask;
+ unit_update_member_masks(s);
+ }
+}
+
static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
- char *path = NULL;
+ _cleanup_free_ char *path;
int r;
- bool is_in_hash = false;
+ bool was_in_hash = false;
assert(u);
path = unit_default_cgroup_path(u);
if (!path)
- return -ENOMEM;
+ return log_oom();
r = hashmap_put(u->manager->cgroup_unit, path, u);
if (r == 0)
- is_in_hash = true;
-
- if (r < 0) {
- log_error("cgroup %s exists already: %s", path, strerror(-r));
- free(path);
+ was_in_hash = true;
+ else if (r < 0) {
+ log_error(r == -EEXIST ?
+ "cgroup %s exists already: %s" : "hashmap_put failed for %s: %s",
+ path, strerror(-r));
return r;
}
if (u->cgroup_path) {
r = cg_migrate_everywhere(u->manager->cgroup_supported, u->cgroup_path, path);
if (r < 0)
- log_error("Failed to migrate cgroup %s: %s", path, strerror(-r));
+ log_error("Failed to migrate cgroup from %s to %s: %s",
+ u->cgroup_path, path, strerror(-r));
}
- if (!is_in_hash) {
- /* And remember the new data */
+ if (!was_in_hash) {
+ /* Remember the new data */
free(u->cgroup_path);
u->cgroup_path = path;
+ path = NULL;
}
u->cgroup_realized = true;
return 0;
}
+static bool unit_has_mask_realized(Unit *u, CGroupControllerMask mask) {
+ return u->cgroup_realized && u->cgroup_mask == mask;
+}
+
+/* Check if necessary controllers and attributes for a unit are in place.
+ *
+ * If so, do nothing.
+ * If not, create paths, move processes over, and set attributes.
+ *
+ * Returns 0 on success and < 0 on failure. */
static int unit_realize_cgroup_now(Unit *u) {
CGroupControllerMask mask;
+ int r;
assert(u);
u->in_cgroup_queue = false;
}
- mask = unit_get_cgroup_mask(u) | unit_get_members_mask(u) | unit_get_siblings_mask(u);
- mask &= u->manager->cgroup_supported;
+ mask = unit_get_target_mask(u);
- if (u->cgroup_realized &&
- u->cgroup_mask == mask)
+ /* TODO: Consider skipping this check. It may be redundant. */
+ if (unit_has_mask_realized(u, mask))
return 0;
/* First, realize parents */
- if (UNIT_ISSET(u->slice))
- unit_realize_cgroup_now(UNIT_DEREF(u->slice));
+ if (UNIT_ISSET(u->slice)) {
+ r = unit_realize_cgroup_now(UNIT_DEREF(u->slice));
+ if (r < 0)
+ return r;
+ }
/* And then do the real work */
- return unit_create_cgroups(u, mask);
+ r = unit_create_cgroups(u, mask);
+ if (r < 0)
+ return r;
+
+ /* Finally, apply the necessary attributes. */
+ cgroup_context_apply(unit_get_cgroup_context(u), mask, u->cgroup_path);
+
+ return 0;
}
static void unit_add_to_cgroup_queue(Unit *u) {
unsigned manager_dispatch_cgroup_queue(Manager *m) {
Unit *i;
unsigned n = 0;
+ int r;
while ((i = m->cgroup_queue)) {
assert(i->in_cgroup_queue);
- if (unit_realize_cgroup_now(i) >= 0)
- cgroup_context_apply(unit_get_cgroup_context(i), i->cgroup_mask, i->cgroup_path);
+ r = unit_realize_cgroup_now(i);
+ if (r < 0)
+ log_warning("Failed to realize cgroups for queued unit %s: %s", i->id, strerror(-r));
n++;
}
if (m == u)
continue;
+ /* Skip units that have a dependency on the slice
+ * but aren't actually in it. */
if (UNIT_DEREF(m->slice) != slice)
continue;
+ /* No point in doing cgroup application for units
+ * without active processes. */
+ if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(m)))
+ continue;
+
+ /* If the unit doesn't need any new controllers
+ * and has current ones realized, it doesn't need
+ * any changes. */
+ if (unit_has_mask_realized(m, unit_get_target_mask(m)))
+ continue;
+
unit_add_to_cgroup_queue(m);
}
* unit, we need to first create all parents, but there's more
* actually: for the weight-based controllers we also need to
* make sure that all our siblings (i.e. units that are in the
- * same slice as we are) have cgroup too. Otherwise things
+ * same slice as we are) have cgroups, too. Otherwise things
* would become very uneven as each of their processes would
* get as much resources as all our group together. This call
* will synchronously create the parent cgroups, but will
/* Add all sibling slices to the cgroup queue. */
unit_queue_siblings(u);
- /* And realize this one now */
+ /* And realize this one now (and apply the values) */
r = unit_realize_cgroup_now(u);
- /* And apply the values */
- if (r >= 0)
- cgroup_context_apply(c, u->cgroup_mask, u->cgroup_path);
-
return r;
}
int manager_setup_cgroup(Manager *m) {
_cleanup_free_ char *path = NULL;
+ char *e;
int r;
- char *e, *a;
assert(m);
return r;
}
- /* Already in /system.slice? If so, let's cut this off again */
+ /* LEGACY: Already in /system.slice? If so, let's cut this
+ * off. This is to support live upgrades from older systemd
+ * versions where PID 1 was moved there. */
if (m->running_as == SYSTEMD_SYSTEM) {
e = endswith(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE);
+ if (!e)
+ e = endswith(m->cgroup_root, "/system");
if (e)
*e = 0;
}
log_debug("Release agent already installed.");
}
- /* 4. Realize the system slice and put us in there */
- if (m->running_as == SYSTEMD_SYSTEM) {
- a = strappenda(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE);
- r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, a, 0);
- } else
- r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, 0);
+ /* 4. Make sure we are in the root cgroup */
+ r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, 0);
if (r < 0) {
log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
return r;
~ianmdlvl / elogind.git / blobdiff