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From:   Zi Yan <ziy@nvidia.com>
To:     Yang Shi <shy828301@gmail.com>
Cc:     nao.horiguchi@gmail.com, mhocko@suse.com,
        kirill.shutemov@linux.intel.com, hughd@google.com,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: mempolicy: don't have to split pmd for huge zero page
Date:   Fri, 04 Jun 2021 17:23:51 -0400
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On 4 Jun 2021, at 16:35, Yang Shi wrote:

> When trying to migrate pages to obey mempolicy, the huge zero page is
> split then the page table walk at PTE level just skips zero page.  So i=
t
> seems pointless to split huge zero page, it could be just skipped like
> base zero page.
>
> Set ACTION_CONTINUE to prevent the walk_page_range() split the pmd for
> this case.
>
> Signed-off-by: Yang Shi <shy828301@gmail.com>

LGTM. Thanks.

Reviewed-by: Zi Yan <ziy@nvidia.com>


=E2=80=94
Best Regards,
Yan, Zi

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