From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 352443B05A7; Mon, 24 Aug 2026 11:48:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787572086; cv=none; b=Aiad/iq84R9NIsgjNmcq1MIkc28yBGJhDpOq5EF2biMxd8tUz/Er0R/9BxsBShcVOEVAugVTIxJaSQpt04Xt8iGGqni8Mjid/Y4/lEi2rpKLTS8PTCoouWO6k83vrWwyP7BDeWurTvwdOLTrv4qQnFSJcaJ1UU6dxxDFpmSWnDE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787572086; c=relaxed/simple; bh=VgiN9mOqZ2nMHCxe8Teh3Neg0it/yA0MaK2gEg4XNAQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=BcK/EwptBI3PjdFs0xZddzwa6TMZ0utsnF/W0k/Wx1le4BI9hynP1lxX2Fj+zTWSpO1sO8ybRKfQ2mW+6GYECgatHZjQ9v1nxNCoV9inOPljOqVhNEDa7mfliRQWR2qq5X0MvPtLkIcMgbKgnJyxsR5kokJRErhcIGAMOlsJk6c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kZYLGiz8; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kZYLGiz8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B3531F000E9; Mon, 24 Aug 2026 11:47:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787572084; bh=xnWILcZvAXPIFAU4ds9k+iQvpoOkwI2Z2KySfwbLn7o=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=kZYLGiz8XKSmI+FIu8i76ktaY6BJPhmezuife5zN6x8SqWXB6n28hCH+ws9jcVaN5 P+Dc8Nyvnk0T10K+QDLHfktnn/e9iBR1HC7H2opBXLSnsAAjI63S0Eo9IzOyA7CnbG q3HrxQ/XayzJaziKlOhBUH0fkAhzCE8DTBPlZZE7r12VG9JVncydOWXpOsVh2dN/ZI aXgMDUJOTxKKjKxiYHgw43YQRghaqn7Bmy/R+oluTiROhRJRtlTwpTw4AoqLy+KteW 50yA0nZIE+DxzYQRGy3xkjNlwJW+DMsIYt2/eK2z4kGSzyA01q1+m+UxJlkn0GOpgk e/NGGwJtFX6qw== Message-ID: <65433d1e-95ca-4434-828e-8f381d3384b1@kernel.org> Date: Mon, 24 Aug 2026 13:47:54 +0200 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 03/57] mm/collapse: add collapse.h for the shared collapse state To: Kiryl Shutsemau Cc: akpm@linux-foundation.org, ljs@kernel.org, nico.pache@linux.dev, baolin.wang@linux.alibaba.com, baohua@kernel.org, dev.jain@arm.com, hughd@google.com, lance.yang@linux.dev, liam@infradead.org, mhocko@suse.com, rppt@kernel.org, ryan.roberts@arm.com, shuah@kernel.org, surenb@google.com, usama.arif@linux.dev, vbabka@kernel.org, ziy@nvidia.com, usama.anjum@arm.com, agordeev@linux.ibm.com, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, jannh@google.com, willy@infradead.org, pfalcato@suse.de, rostedt@goodmis.org, mhiramat@kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org References: <20260816224609.308019-1-kirill@shutemov.name> <20260816224609.308019-4-kirill@shutemov.name> <3113ac8b-c1ce-4577-9e93-449b70818918@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/20/26 13:11, Kiryl Shutsemau wrote: > On Wed, Aug 19, 2026 at 04:19:41PM +0200, David Hildenbrand (Arm) wrote: >> On 8/17/26 00:45, Kiryl Shutsemau wrote: >>> From: "Kiryl Shutsemau (Meta)" >>> >>> Preparation for building the new collapse engine in its own file. The >>> engine and khugepaged.c need to agree on what a collapse result is and >>> what state a scan carries. >>> >>> Move enum scan_result and struct collapse_control into a new >>> mm/collapse.h. >>> >>> No functional change intended. >>> >>> Assisted-by: Claude-Code:claude-opus-5 >>> Signed-off-by: Kiryl Shutsemau (Meta) >>> --- >> >> BTW, I'm wondering whether it would result in less churn (independent of the >> other changes) to >> >> a) Rename mm/khugeapged.c to mm/collapse.c >> >> b) Move stuff into mm/collapse.h that a new ... >> >> c) mm/khugapegd.c will need. > > I went for a clean collapse.c on purpose: the engine is new code, and a > new file keeps it readable while both mechanisms are in the tree, with 28 > as a plain delete from khugepaged.c. > > Your shape is less churn, though, and it keeps blame: 29-35 move about > 1700 lines as add-and-delete today, and most of that would stay put, with > only the daemon -- mm_slot, the scan loop, sysfs -- extracted into a new > khugepaged.c. > > If you prefer it that way, I can give it a try for v2. > > The rename has to open the series, so it will collide with anything in > flight that touches khugepaged.c. > Kiryl, I have to ask, are you using AI to write your replies? -- Cheers, David