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Date:   Thu, 21 Jun 2018 17:05:40 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     linux-mm@kvack.org, Greg Thelen <gthelen@google.com>,
        Shakeel Butt <shakeelb@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] memcg, oom: move out_of_memory back to the charge
 path
Message-ID: <20180621150540.GO10465@dhcp22.suse.cz>
References: <20180620103736.13880-1-mhocko@kernel.org>
 <20180621080927.GE10465@dhcp22.suse.cz>
 <20180621143751.GA11230@cmpxchg.org>
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On Thu 21-06-18 10:37:51, Johannes Weiner wrote:
> On Thu, Jun 21, 2018 at 10:09:27AM +0200, Michal Hocko wrote:
> > @@ -496,14 +496,14 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
> >  
> >  static inline void mem_cgroup_oom_enable(void)
> >  {
> > -	WARN_ON(current->memcg_may_oom);
> > -	current->memcg_may_oom = 1;
> > +	WARN_ON(current->in_user_fault);
> > +	current->in_user_fault = 1;
> >  }
> >  
> >  static inline void mem_cgroup_oom_disable(void)
> >  {
> > -	WARN_ON(!current->memcg_may_oom);
> > -	current->memcg_may_oom = 0;
> > +	WARN_ON(!current->in_user_fault);
> > +	current->in_user_fault = 0;
> >  }
> 
> Would it make more sense to rename these to
> mem_cgroup_enter_user_fault(), mem_cgroup_exit_user_fault()?

OK, makes sense. It is less explicit about the oom behavior... 

> Other than that, this looks great to me.

Thanks for the review! I will wait few days for other feedback and
retest and repost then.
-- 
Michal Hocko
SUSE Labs