On Wed, Sep 2, 2020 at 7:32 AM Michal Hocko <[email protected]> wrote: > > On Wed 02-09-20 11:53:00, Vlastimil Babka wrote: > > >> > > Thread #2: ccs killer kthread > > >> > > css_killed_work_fn > > >> > > cgroup_mutex <- Grab this Mutex > > >> > > mem_cgroup_css_offline > > >> > > memcg_offline_kmem.part > > >> > > memcg_deactivate_kmem_caches > > >> > > get_online_mems > > >> > > mem_hotplug_lock <- waits for Thread#1 to get read > > >> > > access > > And one more thing. THis has been brought up several times already. > Maybe I have forgoten but why do we take hotplug locks in this path in > the first place? Memory hotplug notifier takes slab_mutex so this > shouldn't be really needed.
Good point, it seems this lock can be completely removed from memcg_deactivate_kmem_caches Pasha > -- > Michal Hocko > SUSE Labs
