On Wed 20-03-24 13:09:07, Waiman Long wrote: > > On 3/20/24 06:03, Pavel Tikhomirov wrote: > > In memory_max_write() we first set memcg->memory.max and only then > > try to enforce it in loop. What if while we are in loop someone else > > have changed memcg->memory.max but we are still trying to enforce > > the old value? I believe this can lead to nasty consequence like getting > > an oom on perfectly fine cgroup within it's limits or excess reclaim. > > Concurrent write to the same cgroup control file is not possible as the > underlying kernfs_open_file structure has a mutex that serialize access to > the file. This is good to know and I was not aware of that. Thanks! -- Michal Hocko SUSE Labs
