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Thu, 18 Mar 2021 14:00:40 +0000 Received: from MN2PR12MB3823.namprd12.prod.outlook.com ([fe80::a1b1:5d8:47d7:4b60]) by MN2PR12MB3823.namprd12.prod.outlook.com ([fe80::a1b1:5d8:47d7:4b60%7]) with mapi id 15.20.3955.018; Thu, 18 Mar 2021 14:00:39 +0000 From: "Zi Yan" To: "Miaohe Lin" Cc: akpm@linux-foundation.org, willy@infradead.org, william.kucharski@oracle.com, vbabka@suse.cz, peterx@redhat.com, yulei.kernel@gmail.com, walken@google.com, aneesh.kumar@linux.ibm.com, rcampbell@nvidia.com, thomas_os@shipmail.org, yang.shi@linux.alibaba.com, richard.weiyang@linux.alibaba.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org 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 X-Mailer: MailMate (1.14r5757) 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> Content-Type: multipart/signed; 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identity=mailfrom; envelope-from=""; helo=NAM02-BL2-obe.outbound.protection.outlook.com; client-ip=40.107.75.41 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616076042-875612 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --=_MailMate_17D8B763-DE2B-434A-9907-625CB52DFF3A_= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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 > --- > mm/huge_memory.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > LGTM. Reviewed-by: Zi Yan =E2=80=94 Best Regards, Yan Zi --=_MailMate_17D8B763-DE2B-434A-9907-625CB52DFF3A_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEEh7yFAW3gwjwQ4C9anbJR82th+ooFAmBTXQAPHHppeUBudmlk aWEuY29tAAoJEJ2yUfNrYfqKW60QAKGA3vf9u4pWk35ElLMg48bTKWVl6b/k3RnQ 43HeWlpIqEIYMtyqmz96HNoUr8QQHICZTNl31RQ/Eh7KPAoWyn7DItRkfQw3Ml09 sSQA9/38DzCJIVvh8EZkq+Kxxc2zYLcKeUlAJDecYmwml4vVA6W1NiepKi4zqcfj UKSaj2Y7XPT//l2CTLuvHilZ5H6DCugHHgfrlX7Kv4fz7+DUsvOHJMCVhF4YmrWF YIqf3LKwiXvdbLaPBkZqK9A8PVb+yD9IMjr8QBOezeayDwfER7+QnNUfwP+xTM9F HLL/Km1X9YJI4a2lMpAsHOQUDnx1IOqTsc0/h+sh86NP3yJS1WBACkBz06oKg15a eu3OCOYkfI26w3KcWsiYuwg2iGtpf/0Q69bI9zJMxz9tshI1hEFlJ2SG7NGFv+n3 E/W85lJp3YN/hvnZoc0LS871yFFV1EiHFbIYtGNET4gTfWnbnChk8y9dVQOUVyqE dmeUEdxLix2o+rb4PLXdJsQrSl5iixqi5UZl8hdJVmH6dMeUwGkbb5XohrQwTO9I DUunGJfr6QDFGn8e9MzpK0jX8MbrT1WkEWmnxoaMWa/2UJMYhXHdu1OJEfV9vmz3 YZFPbIVVFUdl6Eb+sQzTzjUDFFSkwfDs4EjH7Sdrl0QaMsd2WxeMwy1xDhTjENnh WKW6QXqk =Gqpk -----END PGP SIGNATURE----- --=_MailMate_17D8B763-DE2B-434A-9907-625CB52DFF3A_=--