/*
* Generate an array of cgroup subsystem pointers. At boot time, this is
- * populated up to CGROUP_BUILTIN_SUBSYS_COUNT, and modular subsystems are
+ * populated with the built in subsystems, and modular subsystems are
* registered after that. The mutable section of this array is protected by
* cgroup_mutex.
*/
-#define SUBSYS(_x) &_x ## _subsys,
+#define SUBSYS(_x) [_x ## _subsys_id] = &_x ## _subsys,
+#define IS_SUBSYS_ENABLED(option) IS_BUILTIN(option)
static struct cgroup_subsys *subsys[CGROUP_SUBSYS_COUNT] = {
#include <linux/cgroup_subsys.h>
};
* take duplicate reference counts on a subsystem that's already used,
* but rebind_subsystems handles this case.
*/
- for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
unsigned long bit = 1UL << i;
if (!(bit & opts->subsys_mask))
* raced with a module_delete call, and to the user this is
* essentially a "subsystem doesn't exist" case.
*/
- for (i--; i >= CGROUP_BUILTIN_SUBSYS_COUNT; i--) {
+ for (i--; i >= 0; i--) {
/* drop refcounts only on the ones we took */
unsigned long bit = 1UL << i;
static void drop_parsed_module_refcounts(unsigned long subsys_mask)
{
int i;
- for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
unsigned long bit = 1UL << i;
if (!(bit & subsys_mask))
set_bit(CGRP_CLONE_CHILDREN, &cgrp->flags);
for_each_subsys(root, ss) {
- struct cgroup_subsys_state *css = ss->create(cgrp);
+ struct cgroup_subsys_state *css;
+ css = ss->create(cgrp);
if (IS_ERR(css)) {
err = PTR_ERR(css);
goto err_destroy;
/* At error, ->destroy() callback has to free assigned ID. */
if (clone_children(parent) && ss->post_clone)
ss->post_clone(cgrp);
+
+ if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&
+ parent->parent) {
+ pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n",
+ current->comm, current->pid, ss->name);
+ if (!strcmp(ss->name, "memory"))
+ pr_warning("cgroup: \"memory\" requires setting use_hierarchy to 1 on the root.\n");
+ ss->warned_broken_hierarchy = true;
+ }
}
list_add(&cgrp->sibling, &cgrp->parent->children);
* since cgroup_init_subsys will have already taken care of it.
*/
if (ss->module == NULL) {
- /* a few sanity checks */
- BUG_ON(ss->subsys_id >= CGROUP_BUILTIN_SUBSYS_COUNT);
+ /* a sanity check */
BUG_ON(subsys[ss->subsys_id] != ss);
return 0;
}
/* init base cftset */
cgroup_init_cftsets(ss);
- /*
- * need to register a subsys id before anything else - for example,
- * init_cgroup_css needs it.
- */
mutex_lock(&cgroup_mutex);
- /* find the first empty slot in the array */
- for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
- if (subsys[i] == NULL)
- break;
- }
- if (i == CGROUP_SUBSYS_COUNT) {
- /* maximum number of subsystems already registered! */
- mutex_unlock(&cgroup_mutex);
- return -EBUSY;
- }
- /* assign ourselves the subsys_id */
- ss->subsys_id = i;
- subsys[i] = ss;
+ subsys[ss->subsys_id] = ss;
/*
* no ss->create seems to need anything important in the ss struct, so
css = ss->create(dummytop);
if (IS_ERR(css)) {
/* failure case - need to deassign the subsys[] slot. */
- subsys[i] = NULL;
+ subsys[ss->subsys_id] = NULL;
mutex_unlock(&cgroup_mutex);
return PTR_ERR(css);
}
if (ret) {
dummytop->subsys[ss->subsys_id] = NULL;
ss->destroy(dummytop);
- subsys[i] = NULL;
+ subsys[ss->subsys_id] = NULL;
mutex_unlock(&cgroup_mutex);
return ret;
}
mutex_lock(&cgroup_mutex);
/* deassign the subsys_id */
- BUG_ON(ss->subsys_id < CGROUP_BUILTIN_SUBSYS_COUNT);
subsys[ss->subsys_id] = NULL;
/* remove subsystem from rootnode's list of subsystems */
for (i = 0; i < CSS_SET_TABLE_SIZE; i++)
INIT_HLIST_HEAD(&css_set_table[i]);
- /* at bootup time, we don't worry about modular subsystems */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
+ /* at bootup time, we don't worry about modular subsystems */
+ if (!ss || ss->module)
+ continue;
+
BUG_ON(!ss->name);
BUG_ON(strlen(ss->name) > MAX_CGROUP_TYPE_NAMELEN);
BUG_ON(!ss->create);
if (err)
return err;
- /* at bootup time, we don't worry about modular subsystems */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
+
+ /* at bootup time, we don't worry about modular subsystems */
+ if (!ss || ss->module)
+ continue;
if (!ss->early_init)
cgroup_init_subsys(ss);
if (ss->use_id)
{
if (need_forkexit_callback) {
int i;
- /*
- * forkexit callbacks are only supported for builtin
- * subsystems, and the builtin section of the subsys array is
- * immutable, so we don't need to lock the subsys array here.
- */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
+
+ /*
+ * forkexit callbacks are only supported for
+ * builtin subsystems.
+ */
+ if (!ss || ss->module)
+ continue;
+
if (ss->fork)
ss->fork(child);
}
tsk->cgroups = &init_css_set;
if (run_callbacks && need_forkexit_callback) {
- /*
- * modular subsystems can't use callbacks, so no need to lock
- * the subsys array
- */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
+
+ /* modular subsystems can't use callbacks */
+ if (!ss || ss->module)
+ continue;
+
if (ss->exit) {
struct cgroup *old_cgrp =
rcu_dereference_raw(cg->subsys[i])->cgroup;
while ((token = strsep(&str, ",")) != NULL) {
if (!*token)
continue;
- /*
- * cgroup_disable, being at boot time, can't know about module
- * subsystems, so we don't worry about them.
- */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
+ /*
+ * cgroup_disable, being at boot time, can't
+ * know about module subsystems, so we don't
+ * worry about them.
+ */
+ if (!ss || ss->module)
+ continue;
+
if (!strcmp(token, ss->name)) {
ss->disabled = 1;
printk(KERN_INFO "Disabling %s control group"
projects / firefly-linux-kernel-4.4.55.git / blobdiff