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Date: Thu, 16 Oct 2014 14:52:48 -0700
Message-ID: <CAM_iQpUFBDscS2n41FdE3S016c_jkb4HaKomy14G7Ez9x4w3+g@mail.gmail.com>
Subject: Re: + freezer-check-oom-kill-while-being-frozen.patch added to -mm tree
From: Cong Wang <xiyou.wangcong@gmail.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>, David Rientjes <rientjes@google.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>, Tejun Heo <tj@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, Oct 16, 2014 at 2:35 PM, Oleg Nesterov <oleg@redhat.com> wrote:
>
> If a task B is already frozen, it sleeps in D state.
>
> If OOM selects B as a victim after that, it won't be woken by
> SIGKILL, thus it obviously can't call should_thaw_current() and
> notice TIF_MEMDIE.

I see your point now, it would be more clear if you can just quote
the patch instead of changelog.

So are you saying the loop in __refrigerator() is useless? Since
it will always stay in asleep after schedule()?

>
> Btw, I also do not understand the cgroup_freezing() check in
> should_thaw_current(), but this is another story.
>

I hate to repeat the previous discussion. Maybe you can just follow
the link I gave to you? :)

Thanks.