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b=q1ubLa5ljjzM9R80g5IM2NUqQJAAufrLy9Lc+SD9Xr1GdVYWVgjzYAmGZuRuxTgrq 1fSRP+UTlly/Cz4RVZ+6i9Xre+rTKN1l/ssJh+Aaa1Z3KqKB6F/HFBUF0Dglh8WWpg Ymmz+Iu0WY8JftSAE4GKvGGZ3D88MdJBSK8MPOfXrUwKNdSjW0eR1AtLhi1lCWxH6W j3oEVWjl02eIcgUnAt0SB5KrL8ebTO11DTyI5CedBhnF5qNPo3EgKVv32nRmYAx+NT iOVkl1W5bG/FD/TIDLBPc4t6XExo5AfdTw00Ews+IzrbMYCXuc3jYZ0tw7nVExtg0u mt57mpxM328tw== Message-ID: <1a6d8295-e27b-4440-a367-af0432a7af4f@kernel.org> Date: Fri, 6 Feb 2026 10:02:48 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-new v6 2/5] mm: khugepaged: refine scan progress number To: Dev Jain , Vernon Yang Cc: akpm@linux-foundation.org, lorenzo.stoakes@oracle.com, ziy@nvidia.com, baohua@kernel.org, lance.yang@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vernon Yang References: <20260201122554.1470071-1-vernon2gm@gmail.com> <20260201122554.1470071-3-vernon2gm@gmail.com> <85e8ded9-a9eb-4663-9c96-93af60006fb6@kernel.org> <9508744b-e5d5-49ef-825f-eef683892541@arm.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 1DA96C0011 X-Stat-Signature: i1a8byhqfa3wyk9gu61gh7x4es4wy5i4 X-Rspam-User: X-HE-Tag: 1770368572-163916 X-HE-Meta: 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 W65mKn6U PI4fZGR5/D1H+w4dXaxNkZHIuHcCVG04KgT6TpbzH56x7GuVPaNDVPoDHQA6V0w7j6USL66y+VxQl2DWEEt4x84b/S9pW4Ks/u5d5il9YnbCXFPS4PR2guRAqAvHkKFKp1xuUmXFU1Dgb+LgicPF1NTukG1YqF8haFlSrHOJmE7wEL8LGSRKbVVdDVS0dG9mOEFhCszOKEl2hhIaswn7iXpAWrOZq59rvYWhXzT1XPk9dzEQdIoqiyBuORuAFHdqvyQWohibeTe8B1ZgyngufM3yrHg1Xx+eSUg0CffAESyEtDvAxyk7NroV8Ww== 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: List-Subscribe: List-Unsubscribe: On 2/5/26 15:25, Dev Jain wrote: > > On 05/02/26 5:41 pm, David Hildenbrand (arm) wrote: >> On 2/5/26 07:08, Vernon Yang wrote: >>> On Thu, Feb 5, 2026 at 5:35 AM David Hildenbrand (arm) >>> wrote: >>> >>> I guess, your meaning is "min(_pte - pte + 1, HPAGE_PMD_NR)", not max(). >> >> Yes! >> >>> >>> >>> I'm also worried that the compiler can't optimize this since the body of >>> the loop is complex, as with Dev's opinion [1]. >> >> Why do we even have to optimize this? :) >> >> Premature ... ? :) > > > I mean .... we don't, but the alternate is a one liner using max(). I'm fine with the max(), but it still seems like adding complexity to optimize something that is nowhere prove to really be a problem. -- Cheers, David