Re: [PATCH 0/2] don't use mapcount() to check large folio sharing

Andrew Morton
2023-07-28T17:24:12Z

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)