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Date:   Fri, 28 Jul 2023 10:24:05 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Yin Fengwei <fengwei.yin@intel.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org, willy@infradead.org,
        vishal.moola@gmail.com, wangkefeng.wang@huawei.com,
        minchan@kernel.org, yuzhao@google.com, david@redhat.com,
        ryan.roberts@arm.com, shy828301@gmail.com
Subject: Re: [PATCH 0/2] don't use mapcount() to check large folio sharing
Message-Id: <20230728102405.7b456eb87fb46042fbce5e4b@linux-foundation.org>
In-Reply-To: <20230728161356.1784568-1-fengwei.yin@intel.com>
References: <20230728161356.1784568-1-fengwei.yin@intel.com>
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On Sat, 29 Jul 2023 00:13:54 +0800 Yin Fengwei <fengwei.yin@intel.com> wrote:

> In madvise_cold_or_pageout_pte_range() and madvise_free_pte_range(),
> folio_mapcount() is used to check whether the folio is shared. But it's
> not correct as folio_mapcount() returns total mapcount of large folio.
> 
> Use folio_estimated_sharers() here as the estimated number is enough.

What are the user-visible runtime effects of these changes?

(and please try to avoid using the same Subject: for different patches)