From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2C095EA7943 for ; Wed, 4 Feb 2026 21:35:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7DEEC6B0088; Wed, 4 Feb 2026 16:35:55 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7A9676B0092; Wed, 4 Feb 2026 16:35:55 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6B6716B0093; Wed, 4 Feb 2026 16:35:55 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 55C6B6B0088 for ; Wed, 4 Feb 2026 16:35:55 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 22DFA1A02E8 for ; Wed, 4 Feb 2026 21:35:55 +0000 (UTC) X-FDA: 84408081870.22.C82B24D Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf27.hostedemail.com (Postfix) with ESMTP id 3A18940012 for ; Wed, 4 Feb 2026 21:35:53 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="L/9m/IXn"; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1770240953; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=CYo9Z9gm7GkJIE7DS2NeS7B/ZlRYyeNGt89dcwlK4CY=; b=UJb1gkouhgGc8WdKsmiuEoWCpbNgwghCbpJlvlXObx7j+LCV7YY1Q0J4dXaChotcq7+jKR 3bUitBdh+DJjrBnMPz57rMI26m8feyygc2Ee/WTv83vHXMpgEp6ncuZcc8SVZq9yQIrb65 RXfh+DIsMajkki4seVD955vzMbTayts= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="L/9m/IXn"; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1770240953; a=rsa-sha256; cv=none; b=3k/nJ++PzkfcXVxHvhbSXmH/jXXJZAhUaDzuHq6BjhqNpjNrlWndpbJ4uqCgzo9jJxUDhW vG349HSFoT92uOyGCWsFAg8R4xXCOOG6BOL3orjVLkO5jXQgp9bneRCMmUuEJFwUF35ghd GE+d/1PR71NxfOrZrvCnPaRhR/IPucM= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 26C6D433BB; Wed, 4 Feb 2026 21:35:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AEB96C4CEF7; Wed, 4 Feb 2026 21:35:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770240952; bh=1JOH5a4nFNxuZdz4tbFuHznJYRc0xRITRKZgjfVW7Hc=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=L/9m/IXnWlC0c5WwHUg0ZZLXnilSkMlJlirxaxYJYkgdi7UhIfufGSdWboQwhBzax yEtHGJTyY86gdLHKEVCo7nv+K4IfaAlrCsnGENt/7rPEenrvbNTtnEOMAjfufIdlLG JK6DwQgveAtVYsIj2ifMZp5XLPzbNoI44nS3gaagOJjBe/7ZI6nTSByplHrPQhIvjc gaj2LejLIUXVbbDkQGG/UgMiUKZulPfa9ZMwky36/cLm/PldS+E/SQCO2a2ZW9FAlE ww+2qt5GXtqlMt6GDY9BErY8Hfh5XUdzasTdRVejT7IFtqLtRsd/5fVEY208/1//pw k2OtV19/J85cQ== Message-ID: Date: Wed, 4 Feb 2026 22:35:48 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-new v6 2/5] mm: khugepaged: refine scan progress number To: Vernon Yang , akpm@linux-foundation.org Cc: lorenzo.stoakes@oracle.com, ziy@nvidia.com, dev.jain@arm.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> From: "David Hildenbrand (arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260201122554.1470071-3-vernon2gm@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 3A18940012 X-Stat-Signature: mmcezt4q31cft86xytfpbqzouokmhtbj X-Rspam-User: X-HE-Tag: 1770240953-671979 X-HE-Meta: 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 S+wh03/C zMCH6uwjvJ8o6Y7bSAlpsgoCuuA3OafHXZvZsZoUXnCMOiosOC5aaxY8ySyCu8nsFLLyvjVcOIwV/3WpFpzz8cxty5RHP8zWdJ1xZCM2/csRgEsDdG3GzsY0etzJ0LeDXa6mxvUXrfLw2dCciOP37Jop/4RSwpizkWFghPrxHfX4W9NlUnxFv8wtYDSST7RX1rIm0h2Nq3VtwvAsgF29NCvCfcI4QDX0/rae61Oajt19gtccXblN9N8jME8f3ggz24E9L0pX3HQwCQG+Pba/CY+JV6gMuKcmIA7kX 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: [...] > + if (cur_progress) { > + if (_pte >= pte + HPAGE_PMD_NR) > + *cur_progress = HPAGE_PMD_NR; > + else > + *cur_progress = _pte - pte + 1; *cur_progress = max(_pte - pte + 1, HPAGE_PMD_NR); ? It's still a bit nasty, though. Can't we just add one at the beginning of the loop and let the compiler optimize that? ;) > + } > pte_unmap_unlock(pte, ptl); > if (result == SCAN_SUCCEED) { > result = collapse_huge_page(mm, start_addr, referenced, > @@ -2286,8 +2301,9 @@ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, > return result; > } > > -static enum scan_result hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr, > - struct file *file, pgoff_t start, struct collapse_control *cc) > +static enum scan_result hpage_collapse_scan_file(struct mm_struct *mm, > + unsigned long addr, struct file *file, pgoff_t start, > + unsigned int *cur_progress, struct collapse_control *cc) > { > struct folio *folio = NULL; > struct address_space *mapping = file->f_mapping; > @@ -2376,6 +2392,8 @@ static enum scan_result hpage_collapse_scan_file(struct mm_struct *mm, unsigned > cond_resched_rcu(); > } > } > + if (cur_progress) > + *cur_progress = max(xas.xa_index - start, 1UL); I would really just keep it simple here and do a *cur_progress = HPAGE_PMD_NR; This stuff is hard to reason about, so I would just leave the file case essentially unchanged. IIRC, it would not affect the numbers you report in the patch description? -- Cheers, David