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Subject: Re: [PATCH v2 3/3] mm: Fix missing mem cgroup soft limit tree updates
To:     Michal Hocko <mhocko@suse.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Ying Huang <ying.huang@intel.com>, linux-mm@kvack.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Tim Chen <tim.c.chen@linux.intel.com>
Message-ID: <fdc2a811-0a05-b706-a6f5-b686507caf56@linux.intel.com>
Date:   Mon, 22 Feb 2021 09:45:12 -0800
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On 2/22/21 12:41 AM, Michal Hocko wrote:

>>
>>
>> Ah, that's true.  The added check for soft_limit_excess is not needed.
>>
>> Do you think it is still a good idea to add patch 3 to
>> restrict the uncharge update in page batch of the same node and cgroup?
> 
> I would rather drop it. The less the soft limit reclaim code is spread
> around the better.
> 

Let's drop patch 3 then.  I find patch 2 is the most critical one in this series.  
Without that patch some cgroups exceeds the soft limit excess very badly.

Tim