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 2CF4BF01804 for ; Fri, 6 Mar 2026 08:06:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 961556B0095; Fri, 6 Mar 2026 03:06:05 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 90EB26B0098; Fri, 6 Mar 2026 03:06:05 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 83BE46B0099; Fri, 6 Mar 2026 03:06:05 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 6F4AD6B0095 for ; Fri, 6 Mar 2026 03:06:05 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 13A4A14043A for ; Fri, 6 Mar 2026 08:06:05 +0000 (UTC) X-FDA: 84514905090.09.09D87F0 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf25.hostedemail.com (Postfix) with ESMTP id 5D675A0013 for ; Fri, 6 Mar 2026 08:06:03 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=e7IawFCH; spf=pass (imf25.hostedemail.com: domain of vbabka@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=vbabka@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=1772784363; 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=wThyn0miyrDFY74RpLM8dbe63bKotUruuQw/jFVwkhs=; b=tKDWY0xwrFV5MlinEkfQaHYVmNP+o+Qx97BOu3UShSL6M57kSaS6kYjanLvzEpL/KDWu/W m1v+7oxRoKvn2LHLyS7Hw/wpmw+FShQrxkqrurPTNmmv8paQ+XGv+TyzwxhlHQwEZSA3/F vnXOkbowtV2TRGv0oecw8+nY2SI8p78= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=e7IawFCH; spf=pass (imf25.hostedemail.com: domain of vbabka@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=vbabka@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772784363; a=rsa-sha256; cv=none; b=Qd1mn/WnRT2NLVryvBLeOITqT8uIR9UiQ1yyU0RhaBqIGF+WzqSI0bJayJ87HAADKZoNcA abqg6Kyxa39vDaryEiljnKT/PNlUMhlMXJtACx/3sIhX0H5XeAbO1ru/MbsiBz0Scx1Qhm NeHHPF27lGXHIJbcgTl0vF3V82qJZHs= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 94C8B60126; Fri, 6 Mar 2026 08:06:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D07EEC4CEF7; Fri, 6 Mar 2026 08:05:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772784362; bh=LBnLAIcGHsesTcn5+nCMswocvTfZ7iqXSC/2rWKf6mo=; h=Date:From:Subject:To:Cc:References:In-Reply-To:From; b=e7IawFCHAhTtgO2GugIeECwEAMAUwS7CAhKdLOxCNwho2wzUPrFmxuX0/LHIKh4Kw qraeumJ9ZyUL57jNsPz2RIDPJu/e0skvhJsg7SPOAgHZWcL4wA41gYL6zd+LS3tapH b4Pd4tRflwrRsgHHdIQkUGAAYYcHq41rSp3OsLdy8ARqGbWLeGLMs999tv6BBhu+cy 10G0W/9KMXIiaWZrXgag1vJzwIY6HCA+8DjBbKyU5wuZhatlvNDmiV4zOTYa6PxYIJ Ex+l2q4U7fRWA3kjpxzxDE2jrt1NzEyabYTyDqMGKONV5Peg3xCTHd/3B6baFYUWXF W6t1hx5WKLGqQ== Message-ID: <3b0b7f7f-c1b0-4f1c-bece-ce0cae130cb5@kernel.org> Date: Fri, 6 Mar 2026 09:05:54 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: "Vlastimil Babka (SUSE)" Subject: Re: [PATCH v4 4/5] mm: rename zone->lock to zone->_lock Content-Language: en-US To: Dmitry Ilvokhin Cc: SeongJae Park , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Axel Rasmussen , Yuanchu Xie , Wei Xu , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Brendan Jackman , Johannes Weiner , Zi Yan , Oscar Salvador , Qi Zheng , Shakeel Butt , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, linux-pm@vger.kernel.org References: <20260304151335.172572-1-sj@kernel.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 5D675A0013 X-Stat-Signature: 4damn69ed85u5btqrtc6pgi9yd59r1yk X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1772784363-748796 X-HE-Meta: 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 o715xwSn glw2Yo1+NR0EbIq/AecWoaDiY01M7g+PRWz3f/tQTnN0QMG6f+jgNJcUwVEdCIH2wKzQUjRn5DQu3s3WnyQgqJMLgCqbOFpOg5hL2AYMcbz0c7flA6FbevZYnhQBwo+BZWiSfHwMTx2QZvN5xDIbHtVpWcc0dxyV1IZjc62wAOsvR9IUdj6wvhfVs/HxPaol95vjyo5QS3bR6KfO/294LDP6xlKBOhXVbtMu49ExgkZJ6IuTxQMJpUdoqbWf+vCUArBCUnQIzJhDgpIKWEqIr7BsvSh9Zu09PuZ/G/0fpD5Ullsth/U4cY3tXPWKh5XAvDTSoB7uXwSby+2A4hb7yy7JFjzFBZZbMCdD8d/wXbu7UiQSXaSZPkkDl3OiUpbXcxazWaepoJXM0l06xsCsQWnYPwckOBqxYiovnoUkMeh+hMAwYXVCWzCiKFLgFBrfvJvXt Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/5/26 19:59, Dmitry Ilvokhin wrote: > On Thu, Mar 05, 2026 at 06:16:26PM +0000, Dmitry Ilvokhin wrote: >> On Thu, Mar 05, 2026 at 10:27:07AM +0100, Vlastimil Babka (SUSE) wrote: >> > On 3/4/26 16:13, SeongJae Park wrote: >> > > On Wed, 4 Mar 2026 13:01:45 +0000 Dmitry Ilvokhin wrote: >> > > >> > >> On Tue, Mar 03, 2026 at 05:50:34PM -0800, SeongJae Park wrote: >> > >> > On Tue, 3 Mar 2026 14:25:55 +0000 Dmitry Ilvokhin wrote: >> > >> > >> > >> > > On Mon, Mar 02, 2026 at 02:37:43PM -0800, Andrew Morton wrote: >> > >> > > > On Mon, 2 Mar 2026 15:10:03 +0100 "Vlastimil Babka (SUSE)" wrote: >> > >> > > > >> > >> > > > > On 2/27/26 17:00, Dmitry Ilvokhin wrote: >> > >> > > > > > This intentionally breaks direct users of zone->lock at compile time so >> > >> > > > > > all call sites are converted to the zone lock wrappers. Without the >> > >> > > > > > rename, present and future out-of-tree code could continue using >> > >> > > > > > spin_lock(&zone->lock) and bypass the wrappers and tracing >> > >> > > > > > infrastructure. >> > >> > > > > > >> > >> > > > > > No functional change intended. >> > >> > > > > > >> > >> > > > > > Suggested-by: Andrew Morton >> > >> > > > > > Signed-off-by: Dmitry Ilvokhin >> > >> > > > > > Acked-by: Shakeel Butt >> > >> > > > > > Acked-by: SeongJae Park >> > >> > > > > >> > >> > > > > I see some more instances of 'zone->lock' in comments in >> > >> > > > > include/linux/mmzone.h and under Documentation/ but otherwise LGTM. >> > >> > > > > >> > >> > > > >> > >> > > > I fixed (most of) that in the previous version but my fix was lost. >> > >> > > >> > >> > > Thanks for the fixups, Andrew. >> > >> > > >> > >> > > I still see a few 'zone->lock' references in Documentation remain on >> > >> > > mm-new. This patch cleans them up, as noted by Vlastimil. >> > >> > > >> > >> > > I'm happy to adjust this patch if anything else needs attention. >> > >> > > >> > >> > > From 9142d5a8b60038fa424a6033253960682e5a51f4 Mon Sep 17 00:00:00 2001 >> > >> > > From: Dmitry Ilvokhin >> > >> > > Date: Tue, 3 Mar 2026 06:13:13 -0800 >> > >> > > Subject: [PATCH] mm: fix remaining zone->lock references >> > >> > > >> > >> > > Signed-off-by: Dmitry Ilvokhin >> > >> > > --- >> > >> > > Documentation/mm/physical_memory.rst | 4 ++-- >> > >> > > Documentation/trace/events-kmem.rst | 8 ++++---- >> > >> > > 2 files changed, 6 insertions(+), 6 deletions(-) >> > >> > > >> > >> > > diff --git a/Documentation/mm/physical_memory.rst b/Documentation/mm/physical_memory.rst >> > >> > > index b76183545e5b..e344f93515b6 100644 >> > >> > > --- a/Documentation/mm/physical_memory.rst >> > >> > > +++ b/Documentation/mm/physical_memory.rst >> > >> > > @@ -500,11 +500,11 @@ General >> > >> > > ``nr_isolate_pageblock`` >> > >> > > Number of isolated pageblocks. It is used to solve incorrect freepage counting >> > >> > > problem due to racy retrieving migratetype of pageblock. Protected by >> > >> > > - ``zone->lock``. Defined only when ``CONFIG_MEMORY_ISOLATION`` is enabled. >> > >> > > + ``zone_lock``. Defined only when ``CONFIG_MEMORY_ISOLATION`` is enabled. >> > >> > >> > >> > Dmitry's original patch [1] was doing 's/zone->lock/zone->_lock/', which aligns >> > >> > to my expectation. But this patch is doing 's/zone->lock/zone_lock/'. Same >> > >> > for the rest of this patch. >> > >> > >> > >> > I was initially thinking this is just a mistake, but I also found Andrew is >> > >> > doing same change [2], so I'm bit confused. Is this an intentional change? >> > >> > >> > >> > [1] https://lore.kernel.org/d61500c5784c64e971f4d328c57639303c475f81.1772206930.git.d@ilvokhin.com >> > >> > [2] https://lore.kernel.org/20260302143743.220eed4feb36d7572fe726cc@linux-foundation.org >> > >> > >> > >> >> > >> Good catch, thanks for pointing this out, SJ. >> > >> >> > >> Originally the mechanical rename was indeed zone->lock -> zone->_lock. >> > >> However, in Documentation I intentionally switched references to >> > >> zone_lock instead of zone->_lock. The reasoning is that _lock is now an >> > >> internal implementation detail, and direct access is discouraged. The >> > >> intended interface is via the zone_lock_*() / zone_unlock_*() wrappers, >> > >> so referencing zone_lock in documentation felt more appropriate than >> > >> mentioning the private struct field (zone->_lock). >> > > >> > > Thank you for this nice and kind clarification, Dmitry! I agree mentioning >> > > zone_[un]lock_*() helpers instead of the hidden member (zone->_lock) can be >> > > better. >> > > >> > > But, I'm concerned if people like me might not aware the intention under >> > > 'zone_lock'. If there is a well-known convention that allows people to know it >> > > is for 'zone_[un]lock_*()' helpers, making it more clear would be nice, in my >> > > humble opinion. If there is such a convention but I'm just missing it, please >> > > ignore. If I'm not, for eaxmaple, >> > > >> > > "protected by ``zone->lock``" could be re-wrote to >> > > "protected by ``zone_[un]lock_*()`` locking helpers" or, >> > > "protected by zone lock helper functions (``zone_[un]lock_*()``)" ? >> > > >> > >> >> > >> That said, I agree this creates inconsistency with the mechanical >> > >> rename, and I'm happy to adjust either way: either consistently refer >> > >> to the wrapper API, or keep documentation aligned with zone->_lock. >> > >> >> > >> I slightly prefer referring to the wrapper API, but don't have a strong >> > >> preference as long as we're consistent. >> > > >> > > I also think both approaches are good. But for the wrapper approach, I think >> > > giving more contexts rather than just ``zone_lock`` to readers would be nice. >> > >> > Grep tells me that we also have comments mentioning simply "zone lock", btw. >> > And it's also a term used often in informal conversations. Maybe we could >> > just standardize on that in comments/documentations as it's easier to read. >> > Discovering that the field is called _lock and that wrappers should be used, >> > is hopefully not that difficult. >> >> Thanks for the suggestion, Vlastimil. That sounds reasonable to me as >> well. I'll update the comments and documentation to consistently use >> "zone lock". > > Following the suggestion from SJ and Vlastimil, I prepared fixup to > standardize documentation and comments on the term "zone lock". > > The patch is based on top of the current mm-new. > > Andrew, please let me know if you would prefer a respin of the series > instead. > > From 267cda3e0e160f97b346009bc48819bfeed92e52 Mon Sep 17 00:00:00 2001 > From: Dmitry Ilvokhin > Date: Thu, 5 Mar 2026 10:36:17 -0800 > Subject: [PATCH] mm: documentation: standardize on "zone lock" terminology > > During review of the zone lock tracing series it was suggested to > standardize documentation and comments on the term "zone lock" > instead of using zone_lock or referring to the internal field > zone->_lock. > > Update references accordingly. > > Signed-off-by: Dmitry Ilvokhin Acked-by: Vlastimil Babka (SUSE) Thanks!