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 38E39CAC5A7 for ; Sat, 20 Sep 2025 12:43:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 90BFE8E0005; Sat, 20 Sep 2025 08:43:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BD868E0001; Sat, 20 Sep 2025 08:43:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7D3868E0005; Sat, 20 Sep 2025 08:43:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 6D0228E0001 for ; Sat, 20 Sep 2025 08:43:03 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 25A171D8DA9 for ; Sat, 20 Sep 2025 12:43:03 +0000 (UTC) X-FDA: 83909593446.09.FD32F69 Received: from out-188.mta0.migadu.com (out-188.mta0.migadu.com [91.218.175.188]) by imf30.hostedemail.com (Postfix) with ESMTP id E4A3580011 for ; Sat, 20 Sep 2025 12:43:00 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=IKg7aAFg; spf=pass (imf30.hostedemail.com: domain of lance.yang@linux.dev designates 91.218.175.188 as permitted sender) smtp.mailfrom=lance.yang@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1758372181; 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=HwT6WLsca0cExAFMnQuLDNi7G4kZxd7/STjhVcD78V4=; b=7u/dixIEdKSGbCkttlqTQmoSpdO2C+qJyy5QuWCwVu8Gp03v3nYYr1gD7ld4LlN/qbJt1L xOePa5GB2sP0HM/iUnOyFKyHrP/kofXqCD4+ZHzkUeNC8CgfIw4RlwkP1JpuVeftLWAwTf uTAREEGfDbaWDjOSsbR6EiOuJT4Ntl8= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1758372181; a=rsa-sha256; cv=none; b=6MbraBTbFKin9P099N0Nxlz689IUkchff2EPzroW3p9FQ1ok+iRViQPyO+RszgTMZS0VJw MCj0uemQ0FUalGxxYPKhs1cBjmeN9tKLDeaJJ85tqI7tfshDwTrIHDaKJ7W0NilLir9B0L 4tNds5gy8gJvRU566M2OlE34JROE3hw= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=IKg7aAFg; spf=pass (imf30.hostedemail.com: domain of lance.yang@linux.dev designates 91.218.175.188 as permitted sender) smtp.mailfrom=lance.yang@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: <05363b2b-f6f2-4743-9620-7f906ec16138@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1758372178; h=from:from: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; bh=HwT6WLsca0cExAFMnQuLDNi7G4kZxd7/STjhVcD78V4=; b=IKg7aAFghezFuw7KeSxCIg6yZO+Q1G33y4WDFweN6wBd+B5n8ZcJwfkHJNqT68INrw5fW5 UX2s9a2wlgJ5Yl7XgMBSA5C1yz49F8i3jhugjfeDF6buVUmuAw4UxMn85Vcqqak8Tc0xYL yyRTa1/LuQyLyS4KHxAxgXTduyrw9c0= Date: Sat, 20 Sep 2025 20:42:52 +0800 MIME-Version: 1.0 Subject: Re: [PATCH] mm/khugepaged: use [pmd|pte]_addr for better reading Content-Language: en-US To: Wei Yang Cc: linux-mm@kvack.org, lorenzo.stoakes@oracle.com, baohua@kernel.org, ryan.roberts@arm.com, Liam.Howlett@oracle.com, dev.jain@arm.com, david@redhat.com, npache@redhat.com, ziy@nvidia.com, akpm@linux-foundation.org, baolin.wang@linux.alibaba.com References: <20250920005416.5865-1-richard.weiyang@gmail.com> <20250920090023.52b4mupfa6dkhtnz@master> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Lance Yang In-Reply-To: <20250920090023.52b4mupfa6dkhtnz@master> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: E4A3580011 X-Stat-Signature: 1pnx3ouwt83w1en7cethbk4ienzie9om X-Rspam-User: X-HE-Tag: 1758372180-672724 X-HE-Meta: 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 +Vavq/X0 n9n/f29X+l2S54Z3htCC61L0/oPnqKOJq2pUcpUYcb07aWWLmjoE3TbI7wv+G57Xzx87f+Glj9cSap0G6XWeFwd58uN/M3DgOae6bKS66hygTJ0lTv3D2XzxuFzUzmuTWfealwtDOiYHRqp8vOjn6ZzzzSJsWj976RWtCrhE8ytgUtS6AGAXFub91SESEkU+fN9DKXUyyE2kHj0U68xC8RO3vstfjTJZoF6+ZHu3JTctkmp3VeIcrC0sD+kgImhaKHnpmF8CZvEFmpb6cwq26omfFGdi7bv5G5nMNfvaar2GFwd3xBIR3QdbxZ4Bero8WEkJRtqD1O0grQU6UAlGHI21mDpSzj3xb2n8a5mdhN61hkY74Av0B8sxXVg== 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 2025/9/20 17:00, Wei Yang wrote: > On Sat, Sep 20, 2025 at 12:30:52PM +0800, Lance Yang wrote: >> >> On 2025/9/20 08:54, Wei Yang wrote: >>> When collapse a pmd, there are two address in use: >>> >>> * address points to the start of pmd >>> * address points to each individual page >>> >>> Current naming is not easy to distinguish these two and error prone. >>> >>> Name the first one to pmd_addr and second one to pte_addr. >>> >>> Signed-off-by: Wei Yang >>> Suggested-by: David Hildenbrand >> >> This renaming makes the code much easier to follow, but just >> some minor style nits below :) >> >> Acked-by: Lance Yang >> >>> --- >>> mm/khugepaged.c | 43 ++++++++++++++++++++++--------------------- >>> 1 file changed, 22 insertions(+), 21 deletions(-) >>> >>> diff --git a/mm/khugepaged.c b/mm/khugepaged.c >>> index 4c957ce788d1..6d03072c1a92 100644 >>> --- a/mm/khugepaged.c >>> +++ b/mm/khugepaged.c >>> @@ -537,18 +537,19 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte, >>> } >>> static int __collapse_huge_page_isolate(struct vm_area_struct *vma, >>> - unsigned long address, >>> + unsigned long pmd_addr, >>> pte_t *pte, >>> struct collapse_control *cc, >>> struct list_head *compound_pagelist) >>> { >>> struct page *page = NULL; >>> struct folio *folio = NULL; >>> + unsigned long pte_addr = pmd_addr; >>> pte_t *_pte; >>> int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0; >> >> Nit: could we refactor this block into the "reverse christmas tree" style? >> > > You mean sth like this? > > int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0; > struct page *page = NULL; > struct folio *folio = NULL; > unsigned long pte_addr = pmd_addr; > pte_t *_pte; That's getting closer. The formatting would be something like this: int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0; unsigned long pte_addr = pmd_addr; struct folio *folio = NULL; struct page *page = NULL; pte_t *_pte; Feel free to change it :)