On 02/11, Roman Gushchin wrote: > > On Wed, Jan 30, 2019 at 05:52:01PM +0100, Oleg Nesterov wrote: > > > > Worse, this looks just wrong. In the latter case, cgroup becomes CGRP_FROZEN > > right after a 2nd task migrates to this cgroup, before this new task calls > > do_freezer_trap() or cgroup_enter_stopped(). > > You're right. So, it looks like the problem is in the equation > nr_tasks_frozen + nr_tasks_stopped == nr_tasks_to_freeze , > because a task can be frozen and stopped simultaneously. > > So, basically it has to be > nr_tasks_frozen + nr_tasks_stopped >= nr_tasks_to_freeze instead. It seems you didn't read the paragraph above, or I missed something... How can "frozen + stopped >= to_freeze" fix the problem with the falsely true CGRP_FROZEN ? Oleg.
