[Devel] Re: [PATCH v2 03/13] memcg: Uncharge all kmem when deleting a cgroup.

[Glauber Costa]

>>> @@ -3719,6 +3721,8 @@ move_account:
>>>                 /* This is for making all *used* pages to be on LRU. */
>>>                 lru_add_drain_all();
>>>                 drain_all_stock_sync(memcg);
>>> +               if (!free_all)
>>> +                       memcg_kmem_move(memcg);
>>
>> Any reason we're not moving kmem charges when free_all is set as well?
>
> Because the slab moving code expects to be synchronized with
> allocations (and itself). We can't call it when there are still tasks
> in the cgroup.

Ok.

Please add an explanation about that.
Oh boy, reading it all now, I started to believe that "free_all" is a 
really poor name =(