From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 9EF3A20CCE4 for ; Wed, 18 Mar 2026 16:50:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773852640; cv=none; b=Wst+2wYhHzqiwy3o2pJHpy798EVo5OkVW3vX7mv/yiHwSfIlrNILaHRfihj45XmIAG9IEZIvASeNtHUQOidpTjM1jHMqvtO5so0DWyqTD1WCapnarZy3YLCznJGp19mVq5bErYpFM46aqN5qm2ztnAPX0QJM3S/W2qy0Z75SFT0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773852640; c=relaxed/simple; bh=CHShc3gz4VGQeM+nfQe0XWpTm4cXxhtY3UqpZDYtXvU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PKFZi0NDpuIawi+nkfCQBNsrfz29efUDsKNIUvktPr7EPxEZoz5ssiJGEF38Lnwc5WpP6TtIL6qDf8hwQOzEm3X5xuD+BPnncj4K8WN37pa56sV3iMJV7wH0Cjh54beLmZKSB1/JN/xwkjA8GLV1FnqYzumUeljPMK2KCCNezSQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=fBfiulsq; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=FbNM+H6d; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fBfiulsq"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="FbNM+H6d" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1773852638; 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=SYosXReCxKHTRtwKmKXBap08lvT05iVcC20sVq3tMSw=; b=fBfiulsqaj4qdVBjzD8SKI13TKF+5GKaH3rnnyelQTf/qtr6hg+Rb/gKWXF+DaoIkqxmCX +moVGALHat8e+e6XVqCUgUU9p+PeJNfwxuIqh0TUIrbV/5sng5Mf8NplC51UOcQMfDKjQu C4ujeMlG5rYx41vA3b7DFKgm8upzXiU= Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-463-FuSgkP4PM0qcKY6Na9Wedg-1; Wed, 18 Mar 2026 12:50:37 -0400 X-MC-Unique: FuSgkP4PM0qcKY6Na9Wedg-1 X-Mimecast-MFC-AGG-ID: FuSgkP4PM0qcKY6Na9Wedg_1773852637 Received: by mail-qt1-f197.google.com with SMTP id d75a77b69052e-50921f7da6dso466451cf.0 for ; Wed, 18 Mar 2026 09:50:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1773852637; x=1774457437; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:content-language:from :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=SYosXReCxKHTRtwKmKXBap08lvT05iVcC20sVq3tMSw=; b=FbNM+H6dxDmbioJSH9EoC0gdYhquE0+pwEMA+UkIiK9qoCH7kbDlodnMmmYTrMpD5m nL5BODM6W0DPpx9nBvZD0HZ47hleva0g3he0PbQIyamOFgA3HR1c3QPbdbi1trZWc6av 3y37FAlbfG+N2UvME0wgHaTkNd/3gNBeRxSB1x1waI4GiPevjmvAaJfzcWEepmwEwd+F BY92tvSsL/iqmtu/6a0M3Skl6Y9xJss1fcpbVqqlEEau/MbshIwcbMwAu5tm5zrhmhet aDSe5rzXRF5yEE9zuEQ/WTmmxvHwo4LM7Cm63xpclOpH27v11NEARBsUm9A8wx6z7Jr0 4eUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773852637; x=1774457437; h=content-transfer-encoding:in-reply-to:content-language:from :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=SYosXReCxKHTRtwKmKXBap08lvT05iVcC20sVq3tMSw=; b=M7CjGPcO7CHoLQPugfTM3VLA1GsjDMytPIGvp39WsCMrLbV/qidZdv0igJdKTHjDWe JauMr+Q9+VwjXf4S8GLlVUq5xtlVXyvfDeOdieCDREmS6cBMEWtsxTTzAkAGt54KhhJZ DrO8q8+I9w7kcoiJGwTkrTT6XJyOUgro03LcosYXeODeFOlCO8IlLel88O1jXDPWZNlV +tHo2hD538HksvirpoabzFkf4u1JrLEdDo/v9pxT16ejmyXH5LIJ/1HBD60TrDFIL1wQ WYKNMR+lLHSdPrUnQ34omB009VG4B/a0xVDemlLPVoEUQhyZxHkinGScFeIjWaQKzEqT YwcA== X-Gm-Message-State: AOJu0YymVrEhCgULylDgVP1MLB+mEy6VbaG4UnM/vKzD/evw7AZ8v4xu EtYmzfw9+vA1YQPXynVTtKii0GHkiB+Zv540I5lePvnyi1PCyDzh5vlK+GjNeM6eJuCpNDOZJv1 gba+b5ij5K2LAK7AVJDE4frSjNbtZJRGnlgzRhO02EfSIdRw0+wjOq9qrSE/c66VWnQ== X-Gm-Gg: ATEYQzxqqC+d3JmwnCvqZItN2Dqd1sHtba2p5RExhPav90nw7CqhxSp5CXq3+Nf5Ue2 EXsALvUeuj1TkBsiBCT7whkUszFj8LZswpR2XBYVZhCu3/dzWMN3uOASfv8yJwj0E6zzr8gCd67 Md/M6RQENsdi4zHZo1Jf6fCYjukc7j5vhdOBmavU8HRUJ01fyla7a/do4Jwx18nXuEFikZtTIUm QY+WZ3eIhtlhDM3ikn7cov7KZ6xgf7gE5TFKvGBz4i4eOnlHNtv/eE17RXfagVsvYemtAolyZRk 9ysQ8jp1+KCk0ZrSWp7XUwa0Ke9KIh/5dQrw51sXpDFHU27lO/iDH1kkmJLPRXy+qJoWrykNjgA Jj4QGM5PYHmrww2aTL3ZqxWH0Y+tLSU+TmFUfgy6HxV8XYjUnP3jggQcasPnx X-Received: by 2002:ac8:5d43:0:b0:509:59c:579e with SMTP id d75a77b69052e-50b14793337mr50991151cf.28.1773852636474; Wed, 18 Mar 2026 09:50:36 -0700 (PDT) X-Received: by 2002:ac8:5d43:0:b0:509:59c:579e with SMTP id d75a77b69052e-50b14793337mr50990641cf.28.1773852635662; Wed, 18 Mar 2026 09:50:35 -0700 (PDT) Received: from [192.168.10.111] (c-76-154-99-94.hsd1.co.comcast.net. [76.154.99.94]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-50b1348a168sm30717451cf.5.2026.03.18.09.50.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 18 Mar 2026 09:50:35 -0700 (PDT) Message-ID: <7d47a845-8e15-478f-8a4f-a3a04d6b7469@redhat.com> Date: Wed, 18 Mar 2026 10:50:29 -0600 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-unstable v3 3/5] mm/khugepaged: define KHUGEPAGED_MAX_PTES_LIMIT as HPAGE_PMD_NR - 1 To: "Lorenzo Stoakes (Oracle)" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, aarcange@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, apopple@nvidia.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, byungchul@sk.com, catalin.marinas@arm.com, cl@gentwo.org, corbet@lwn.net, dave.hansen@linux.intel.com, david@kernel.org, dev.jain@arm.com, gourry@gourry.net, hannes@cmpxchg.org, hughd@google.com, jackmanb@google.com, jack@suse.cz, jannh@google.com, jglisse@google.com, joshua.hahnjy@gmail.com, kas@kernel.org, lance.yang@linux.dev, Liam.Howlett@oracle.com, lorenzo.stoakes@oracle.com, mathieu.desnoyers@efficios.com, matthew.brost@intel.com, mhiramat@kernel.org, mhocko@suse.com, peterx@redhat.com, pfalcato@suse.de, rakie.kim@sk.com, raquini@redhat.com, rdunlap@infradead.org, richard.weiyang@gmail.com, rientjes@google.com, rostedt@goodmis.org, rppt@kernel.org, ryan.roberts@arm.com, shivankg@amd.com, sunnanyong@huawei.com, surenb@google.com, thomas.hellstrom@linux.intel.com, tiwai@suse.de, usamaarif642@gmail.com, vbabka@suse.cz, vishal.moola@gmail.com, wangkefeng.wang@huawei.com, will@kernel.org, willy@infradead.org, yang@os.amperecomputing.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, zokeefe@google.com References: <20260311211315.450947-1-npache@redhat.com> <20260311211315.450947-4-npache@redhat.com> From: Nico Pache Content-Language: en-US, en-ZM In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/16/26 12:18 PM, Lorenzo Stoakes (Oracle) wrote: > On Wed, Mar 11, 2026 at 03:13:13PM -0600, Nico Pache wrote: >> The value (HPAGE_PMD_NR - 1) is used often in the khugepaged code to >> signify the limit of the max_ptes_* values. Add a define for this to >> increase code readability and reuse. >> >> Acked-by: Pedro Falcato >> Acked-by: David Hildenbrand (Arm) >> Reviewed-by: Baolin Wang >> Reviewed-by: Zi Yan >> Signed-off-by: Nico Pache > > Hm didn't I suggest this? Or actually I can't remember :P I think you suggested most of these patches ;P Ill make sure to add your SB tag on the followups! > > Anyway LGTM, so: > > Reviewed-by: Lorenzo Stoakes (Oracle) Thank you! > >> --- >> mm/khugepaged.c | 9 +++++---- >> 1 file changed, 5 insertions(+), 4 deletions(-) >> >> diff --git a/mm/khugepaged.c b/mm/khugepaged.c >> index d3bdec4ec61b..db77ab5b315e 100644 >> --- a/mm/khugepaged.c >> +++ b/mm/khugepaged.c >> @@ -89,6 +89,7 @@ static DECLARE_WAIT_QUEUE_HEAD(khugepaged_wait); >> * >> * Note that these are only respected if collapse was initiated by khugepaged. >> */ >> +#define KHUGEPAGED_MAX_PTES_LIMIT (HPAGE_PMD_NR - 1) >> unsigned int khugepaged_max_ptes_none __read_mostly; >> static unsigned int khugepaged_max_ptes_swap __read_mostly; >> static unsigned int khugepaged_max_ptes_shared __read_mostly; >> @@ -259,7 +260,7 @@ static ssize_t max_ptes_none_store(struct kobject *kobj, >> unsigned long max_ptes_none; >> >> err = kstrtoul(buf, 10, &max_ptes_none); >> - if (err || max_ptes_none > HPAGE_PMD_NR - 1) >> + if (err || max_ptes_none > KHUGEPAGED_MAX_PTES_LIMIT) >> return -EINVAL; >> >> khugepaged_max_ptes_none = max_ptes_none; >> @@ -284,7 +285,7 @@ static ssize_t max_ptes_swap_store(struct kobject *kobj, >> unsigned long max_ptes_swap; >> >> err = kstrtoul(buf, 10, &max_ptes_swap); >> - if (err || max_ptes_swap > HPAGE_PMD_NR - 1) >> + if (err || max_ptes_swap > KHUGEPAGED_MAX_PTES_LIMIT) >> return -EINVAL; >> >> khugepaged_max_ptes_swap = max_ptes_swap; >> @@ -310,7 +311,7 @@ static ssize_t max_ptes_shared_store(struct kobject *kobj, >> unsigned long max_ptes_shared; >> >> err = kstrtoul(buf, 10, &max_ptes_shared); >> - if (err || max_ptes_shared > HPAGE_PMD_NR - 1) >> + if (err || max_ptes_shared > KHUGEPAGED_MAX_PTES_LIMIT) >> return -EINVAL; >> >> khugepaged_max_ptes_shared = max_ptes_shared; >> @@ -382,7 +383,7 @@ int __init khugepaged_init(void) >> return -ENOMEM; >> >> khugepaged_pages_to_scan = HPAGE_PMD_NR * 8; >> - khugepaged_max_ptes_none = HPAGE_PMD_NR - 1; >> + khugepaged_max_ptes_none = KHUGEPAGED_MAX_PTES_LIMIT; >> khugepaged_max_ptes_swap = HPAGE_PMD_NR / 8; >> khugepaged_max_ptes_shared = HPAGE_PMD_NR / 2; >> >> -- >> 2.53.0 >> >