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Date:   Mon, 2 Aug 2021 15:50:41 +0100
From:   Aaron Tomlin <atomlin@redhat.com>
To:     David Rientjes <rientjes@google.com>
Cc:     linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@suse.com,
        penguin-kernel@i-love.sakura.ne.jp, llong@redhat.com,
        neelx@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] mm/oom_kill: show oom eligibility when displaying the
 current memory state of all tasks
Message-ID: <20210802145041.w7lqdt77qguwbwag@ava.usersys.com>
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 <fa6e3682-abae-f656-fec4-178a608face5@google.com>
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On Sun 2021-08-01 20:49 -0700, David Rientjes wrote:
> oom_score_adj is shown already in the tasklist dump, I'm not sure what 
> value this adds.

Fair enough.

> 
> > +	else if (test_bit(MMF_OOM_SKIP, &p->mm->flags)
> > +		return "R";
> > +	else if (in_vfork(p))
> > +		return "V";
> 
> This is going to be racy, we can't show that a task that is emitted as 
> part of the tasklist dump was did not have in_vfork() == true at the time 
> oom_badness() was called.

Yes, this is true.

> Wouldn't it be better to simply print the output of oom_badness() to the 
> tasklist dump instead so we get complete information?

I think this would be acceptable.

> We could simply special case a LONG_MIN return value as -1000 or "min".

Agreed.


Kind regards,

-- 
Aaron Tomlin