On Tue 19-06-12 09:09:47, KAMEZAWA Hiroyuki wrote: > (2012/06/18 22:30), Michal Hocko wrote: > > On Mon 18-06-12 20:57:23, KAMEZAWA Hiroyuki wrote: > >> 2 follow-up patches for "memcg: move charges to root cgroup if use_hierarchy=0", > >> developped/tested onto memcg-devel tree. Maybe no HUNK with -next and -mm.... > >> -Kame > >> == > >> memcg: remove -EINTR at rmdir() > >> > >> By commit "memcg: move charges to root cgroup if use_hierarchy=0", > >> no memory reclaiming will occur at removing memory cgroup. > > > > OK, so the there are only 2 reasons why move_parent could fail in this > > path. 1) it races with somebody else who is uncharging or moving the > > charge and 2) THP split. > > 1) works for us and 2) doens't seem to be serious enough to expect that > > it would stall rmdir on the group for unbound amount of time so the > > change is safe (can we make this into the changelog please?). > > > > Yes. But the failure of move_parent() (-EBUSY) will be retried. > > Remaining problems are > - attaching task while pre_destroy() is called. > - creating child cgroup while pre_destroy() is called. I don't know why but I thought that tasks and subgroups are not alowed when pre_destroy is called. If this is possible then we probably want to check for pending signals or at least add cond_resched. > > I think I need to make a patch for cgroup layer as I previously posted. > I'd like to try again. > > Thanks, > -Kame > -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>