diff options
| -rw-r--r-- | mm/memcontrol.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b29b850cf399..a4d3282493b6 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5326,7 +5326,6 @@ static struct mem_cgroup *mem_cgroup_alloc(void) INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue); memcg->deferred_split_queue.split_queue_len = 0; #endif - idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); lru_gen_init_memcg(memcg); return memcg; fail: @@ -5398,14 +5397,27 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css) if (alloc_shrinker_info(memcg)) goto offline_kmem; - /* Online state pins memcg ID, memcg ID pins CSS */ - refcount_set(&memcg->id.ref, 1); - css_get(css); - if (unlikely(mem_cgroup_is_root(memcg))) queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); lru_gen_online_memcg(memcg); + + /* Online state pins memcg ID, memcg ID pins CSS */ + refcount_set(&memcg->id.ref, 1); + css_get(css); + + /* + * Ensure mem_cgroup_from_id() works once we're fully online. + * + * We could do this earlier and require callers to filter with + * css_tryget_online(). But right now there are no users that + * need earlier access, and the workingset code relies on the + * cgroup tree linkage (mem_cgroup_get_nr_swap_pages()). So + * publish it here at the end of onlining. This matches the + * regular ID destruction during offlining. + */ + idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); + return 0; offline_kmem: memcg_offline_kmem(memcg); |