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 B12113DA7D7 for ; Mon, 16 Mar 2026 18:18:40 +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=1773685120; cv=none; b=GDwV8mNE9BIqwWXflR6ODAExmqNUVsdSlcD0GWUoCetw17yub87ZmP3iKW1kJXAZ2aIi7Ih5iZsHaY3htQbmjEZax6EtfLuff/U2ANWBCSE4ovu0N5+tpdz2qZqY/mWWKLq09X6WHz9aG3fIAj+VuEsMeSO6Z0J2eYo67I5yrLk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773685120; c=relaxed/simple; bh=MMg0evIPGaTN/2UdyQI4UEe3CJoma3zLEV+L9ukhSjY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UpMaMCUCwPAIfdV0/zfdzFTxSEAepSmgd0NSTVsXn0QczjKB7/fpsMp07srtP+fO95q/rFrO09scyxZatgEtLXE1+h+I+/5kep7w9CHBlBNp7CS7a52DdC+biIKopDKwZdwyoQu7vJjONsCa1TbMIBTW3w82/0L6VsYp62VG6Ck= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZO8LSCe3; 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="ZO8LSCe3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E254C19421; Mon, 16 Mar 2026 18:18:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773685119; bh=MMg0evIPGaTN/2UdyQI4UEe3CJoma3zLEV+L9ukhSjY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZO8LSCe3Yfj91WA6DeilqxeaBn/768zT8gNpM2Ujdf8Li0pDTmXUqaUAWELebibXA RHN91Dx7+UL81itDRTW3safhSpvaeK49P1IljPCkfZprMN390o5xjL30tcu5lTPb1m Ubumwud3YWR8uzBg8REs6DKjdmI34T4NI8el7tiQo9YsjCYI1Cot8zuUtK6rRaGu2t woUltCaoM6x+1tf96rWz9Ed9X8cmgkrSckZ74IL8NiN3qT/fsW52eSCaxQdSpAONt8 hNWVv2iU3g04//bsoK2+33NcNmHPwbQNRSaw9P0qeEvbp5+7UoEBAzJ+exg/fpFPlQ YA/BRNF10sxgg== Date: Mon, 16 Mar 2026 18:18:38 +0000 From: "Lorenzo Stoakes (Oracle)" To: Nico Pache 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 Subject: Re: [PATCH mm-unstable v3 3/5] mm/khugepaged: define KHUGEPAGED_MAX_PTES_LIMIT as HPAGE_PMD_NR - 1 Message-ID: References: <20260311211315.450947-1-npache@redhat.com> <20260311211315.450947-4-npache@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260311211315.450947-4-npache@redhat.com> 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 Anyway LGTM, so: Reviewed-by: Lorenzo Stoakes (Oracle) > --- > 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 >