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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.1 MIME-Version: 1.0 In-Reply-To: <7D8F1E5C-5A39-4C76-AD2F-4D0954DB57F5@redhat.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: 1_vn4diuMaGIu8iL36k85w-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000673, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 27.11.19 20:52, David Hildenbrand wrote: >=20 >=20 >> Am 27.11.2019 um 20:37 schrieb Qian Cai : >> >> =EF=BB=BF >> >>> On Nov 27, 2019, at 2:06 PM, David Hildenbrand wrote= : >>> >>> The zone pointer is unique for every node. (in contrast to the zone ind= ex). >> >> I am not sure if it is worth optimizing there. The existing nid check lo= oks quite straight-forward and cheap. >=20 > I understand but strongly dislike your attitude towards code changes ;) >=20 I think that came out wrong, let me rephrase: This is not a performance optimization but a cleanup. Once you understood how zone pointers work, you immediately see why the nid checks are only here for legacy reasons (see "mm/memory_hotplug: we always have a zone in find_(smallest|biggest)_section_pfn" in linux-next). (I am a friend of cleaning up and refactoring code to make it easier to understand, maintain and extend. I was assuming your mentality is to rather keeping code changes minimal if there is a chance to break things - I'm sorry if that assumption was wrong.) --=20 Thanks, David / dhildenb