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From:   "Zi Yan" <ziy@nvidia.com>
To:     "Miaohe Lin" <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, willy@infradead.org,
        william.kucharski@oracle.com, vbabka@suse.cz, peterx@redhat.com,
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        richard.weiyang@linux.alibaba.com, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v3 2/6] mm/huge_memory.c: make get_huge_zero_page() return
 bool
Date:   Thu, 18 Mar 2021 10:00:32 -0400
Message-ID: <65D8C66C-B8A7-4FC6-A658-5932097453F3@nvidia.com>
In-Reply-To: <20210318122722.13135-3-linmiaohe@huawei.com>
References: <20210318122722.13135-1-linmiaohe@huawei.com>
 <20210318122722.13135-3-linmiaohe@huawei.com>
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On 18 Mar 2021, at 8:27, Miaohe Lin wrote:

> It's guaranteed that huge_zero_page will not be NULL if huge_zero_refco=
unt
> is increased successfully. When READ_ONCE(huge_zero_page) is returned,
> there must be a huge_zero_page and it can be replaced with returning 't=
rue'
> when we do not care about the value of huge_zero_page. We can thus make=
 it
> return bool to save READ_ONCE cpu cycles as the return value is just us=
ed
> to check if huge_zero_page exists.
>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  mm/huge_memory.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
LGTM. Reviewed-by: Zi Yan <ziy@nvidia.com>

=E2=80=94
Best Regards,
Yan Zi

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