On Sat, Jun 15, 2019 at 9:49 AM Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> wrote: > > On 2019/06/16 1:11, Shakeel Butt wrote: > > On Sat, Jun 15, 2019 at 6:50 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > >> diff --git a/mm/oom_kill.c b/mm/oom_kill.c > >> index 5a58778c91d4..43eb479a5dc7 100644 > >> --- a/mm/oom_kill.c > >> +++ b/mm/oom_kill.c > >> @@ -161,8 +161,8 @@ static bool oom_unkillable_task(struct task_struct *p, > >> return true; > >> > >> /* When mem_cgroup_out_of_memory() and p is not member of the group */ > >> - if (memcg && !task_in_mem_cgroup(p, memcg)) > >> - return true; > >> + if (memcg) > >> + return false; > > > > This will break the dump_tasks() usage of oom_unkillable_task(). We > > can change dump_tasks() to traverse processes like > > mem_cgroup_scan_tasks() for memcg OOMs. > > While dump_tasks() traverses only each thread group, mem_cgroup_scan_tasks() > traverses each thread. I think mem_cgroup_scan_tasks() traversing threads is not intentional and css_task_iter_start in it should use CSS_TASK_ITER_PROCS as the oom killer only cares about the processes or more specifically mm_struct (though two different thread groups can have same mm_struct but that is fine). > To avoid printk()ing all threads in a thread group, > moving that check to > > if (memcg && !task_in_mem_cgroup(p, memcg)) > continue; > > in dump_tasks() is better? > > > > >> > >> /* p may not have freeable memory in nodemask */ > >> if (!has_intersects_mems_allowed(p, nodemask)) >
