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Date: Thu, 8 Jan 2015 12:51:24 +0100
From: Michal Hocko <mhocko@suse.cz>
To: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        "\\\"Rafael J. Wysocki\\\"" <rjw@rjwysocki.net>,
        David Rientjes <rientjes@google.com>,
        Johannes Weiner <hannes@cmpxchg.org>, Oleg Nesterov <oleg@redhat.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>, linux-pm@vger.kernel.org
Subject: Re: [PATCH -v2 5/5] OOM, PM: make OOM detection in the freezer path
 raceless
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On Fri 05-12-14 17:41:47, Michal Hocko wrote:
[...]
> +bool oom_killer_disable(void)
> +{
> +	/*
> +	 * Make sure to not race with an ongoing OOM killer
> +	 * and that the current is not the victim.
> +	 */
> +	down_write(&oom_sem);
> +	if (test_thread_flag(TIF_MEMDIE)) {
> +		up_write(&oom_sem);
> +		return false;
> +	}
> +
> +	oom_killer_disabled = true;
> +	up_write(&oom_sem);
> +
> +	wait_event(oom_victims_wait, atomic_read(&oom_victims));

Ups brainfart... Should be !atomic_read(&oom_victims). Condition says
for what we are waiting not when we are waiting.

> +
> +	return true;
> +}
[...]
-- 
Michal Hocko
SUSE Labs