From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6837134676F for ; Fri, 6 Feb 2026 09:02:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770368572; cv=none; b=jK3+wTE22B9bI7NamwC67S82hLGeBDCLP7CE49AFadm2z1c0Kqt87sp4gzz1hSVzDr5ojgdmSXiYG1m5A3c+z9NUw/OFoJwCwqlB2SUPfiMUpskfvE6TSm4wYSecLvI3lSeSSGOsKJ9/oR8Ci+q6H9IpFZSj5yjplF0tskGd+X8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770368572; c=relaxed/simple; bh=hkFt2yH4MBr3yZ05qlX5GzMUkIFfehbRgX81ou3KaBU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OnEZuPn9roUH9VwpaNb/0MKiIueb4iDtznxt/d5ExMQJUMNRdIvIaQd977FDhsbVNCfPBiPA1MjDHYo3+GKibBsIVdWnA3XWFOHviSVvciBcnErbBSBkLpO7dBpcZSw0VKVb+MT1c0cICWdZbzDCL1+qFjes3YlIMElFWAnF7h0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q1ubLa5l; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="q1ubLa5l" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9649CC116C6; Fri, 6 Feb 2026 09:02:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770368572; bh=hkFt2yH4MBr3yZ05qlX5GzMUkIFfehbRgX81ou3KaBU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; 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 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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