Re: [PATCH 4/9] oom: oom_kill_process() need to check p is unkillable

KOSAKI Motohiro
2010-06-17T01:51:38Z

> On Wed, Jun 16, 2010 at 08:32:45PM +0900, KOSAKI Motohiro wrote:
> > When oom_kill_allocating_task is enabled, an argument of
> > oom_kill_process is not selected by select_bad_process(), but
> > just out_of_memory() caller task. It mean the task can be
> > unkillable. check it first.
> >
> > Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
> > ---
> > mm/oom_kill.c | 11 +++++++++++
> > 1 files changed, 11 insertions(+), 0 deletions(-)
> >
> > diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> > index 6ca6cb8..3e48023 100644
> > --- a/mm/oom_kill.c
> > +++ b/mm/oom_kill.c
> > @@ -436,6 +436,17 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
> > unsigned long victim_points = 0;
> > struct timespec uptime;
> >
> > + /*
> > + * When oom_kill_allocating_task is enabled, p can be
> > + * unkillable. check it first.
> > + */
> > + if (is_global_init(p) || (p->flags & PF_KTHREAD))
> > + return 1;
> > + if (mem && !task_in_mem_cgroup(p, mem))
> > + return 1;
> > + if (!has_intersects_mems_allowed(p, nodemask))
> > + return 1;
> > +
>
> I think this check could be done before oom_kill_proces in case of
> sysctl_oom_kill_allocating_task, too.

ok.