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Date:   Wed, 22 Jun 2022 11:09:16 +0800
From:   Muchun Song <songmuchun@bytedance.com>
To:     Baolin Wang <baolin.wang@linux.alibaba.com>
Cc:     sj@kernel.org, akpm@linux-foundation.org, mike.kravetz@oracle.com,
        damon@lists.linux.dev, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/damon: Use set_huge_pte_at() to make huge pte old
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On Mon, Jun 20, 2022 at 10:34:42AM +0800, Baolin Wang wrote:
> The huge_ptep_set_access_flags() can not make the huge pte old according
> to the discussion [1], that means we will always mornitor the young state
> of the hugetlb though we stopped accessing the hugetlb, as a result DAMON
> will get inaccurate accessing statistics.
> 
> So changing to use set_huge_pte_at() to make the huge pte old to fix this
> issue.
> 
> [1] https://lore.kernel.org/all/Yqy97gXI4Nqb7dYo@arm.com/
> 
> Fixes: 49f4203aae06 ("mm/damon: add access checking for hugetlb pages")
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>

The changes make sense to me.

Reviewed-by: Muchun Song <songmuchun@bytedance.com>