diff options
| -rw-r--r-- | include/linux/cgroup.h | 3 | ||||
| -rw-r--r-- | mm/memcontrol.c | 17 |
2 files changed, 20 insertions, 0 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 64047ae7fde1..cda7eb2239e1 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -268,6 +268,9 @@ enum { * * - Remount is disallowed. * + * - memcg: use_hierarchy is on by default and the cgroup file for + * the flag is not created. + * * The followings are planned changes. * * - release_agent will be disallowed once replacement notification diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9715c0c491b0..df87bdd4d692 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5814,6 +5814,7 @@ static struct cftype mem_cgroup_files[] = { }, { .name = "use_hierarchy", + .flags = CFTYPE_INSANE, .write_u64 = mem_cgroup_hierarchy_write, .read_u64 = mem_cgroup_hierarchy_read, }, @@ -6784,6 +6785,21 @@ static void mem_cgroup_move_task(struct cgroup *cont, } #endif +/* + * Cgroup retains root cgroups across [un]mount cycles making it necessary + * to verify sane_behavior flag on each mount attempt. + */ +static void mem_cgroup_bind(struct cgroup *root) +{ + /* + * use_hierarchy is forced with sane_behavior. cgroup core + * guarantees that @root doesn't have any children, so turning it + * on for the root memcg is enough. + */ + if (cgroup_sane_behavior(root)) + mem_cgroup_from_cont(root)->use_hierarchy = true; +} + struct cgroup_subsys mem_cgroup_subsys = { .name = "memory", .subsys_id = mem_cgroup_subsys_id, @@ -6794,6 +6810,7 @@ struct cgroup_subsys mem_cgroup_subsys = { .can_attach = mem_cgroup_can_attach, .cancel_attach = mem_cgroup_cancel_attach, .attach = mem_cgroup_move_task, + .bind = mem_cgroup_bind, .base_cftypes = mem_cgroup_files, .early_init = 0, .use_id = 1, |
