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Date:   Tue, 11 Oct 2022 21:01:20 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Tejun Heo <tj@kernel.org>
Cc:     Waiman Long <longman@redhat.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Shakeel Butt <shakeelb@google.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-mm@kvack.org, Chris Down <chris@chrisdown.name>
Subject: Re: [PATCH] mm/memcontrol: Don't increase effective low/min if no
 protection needed
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On Tue 11-10-22 07:04:32, Tejun Heo wrote:
> On Tue, Oct 11, 2022 at 01:00:22PM -0400, Waiman Long wrote:
> > You are right about that. An alternative way to address this issue is to
> > disable memory low event when memory.low isn't set. An user who want to
> > track memory.low event has to set it to a non-zero value. Would that be
> > acceptable?
> 
> Wouldn't it make sense to fix the test? With recursive_prot on, the cgroup
> actually is under low protection and it seems like the correct behavior is
> to report the low events accordingly.

Agreed, the semantic makes sense and it seems to be just the test that
is not aware of it.
-- 
Michal Hocko
SUSE Labs