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 DA50EEF8FF3 for ; Wed, 4 Mar 2026 15:13:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2E26E6B008A; Wed, 4 Mar 2026 10:13:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 28FBA6B008C; Wed, 4 Mar 2026 10:13:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 18E866B0092; Wed, 4 Mar 2026 10:13:56 -0500 (EST) 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 078FB6B008A for ; Wed, 4 Mar 2026 10:13:56 -0500 (EST) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 9A0761B8446 for ; Wed, 4 Mar 2026 15:13:55 +0000 (UTC) X-FDA: 84508725630.15.4B59F9C Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf28.hostedemail.com (Postfix) with ESMTP id EDEEAC0013 for ; Wed, 4 Mar 2026 15:13:53 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=vPvSHVMp; spf=pass (imf28.hostedemail.com: domain of sj@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=sj@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=1772637233; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=vVzlVJCKPmMDMIWZO1x6Q+mabNba4yEUK35mv1gdRxw=; b=sorb4vhZWsnaPg9oWwe5sG4cWFTp531cphjMfh0psxs6I4XrPPpfxfxXPGXTcVXwH1zZ5+ oNnAyoL1xi6kzbEQW8z0w3Koj6PGYlm//XHbyzlqcYspZfrQVg4VOyRx4P+E0rIoS3W56+ hCj5qS1KkBU+DsDzDcUEvR/k3Yeti6k= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=vPvSHVMp; spf=pass (imf28.hostedemail.com: domain of sj@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772637233; a=rsa-sha256; cv=none; b=2hor7+b3osaFUcrMIionA2zToPMZ1mTmZRXJSuREE9N/6e+dmEwRi68AVMp8IR1WvhFmAk gYQquUAlqHir6hnPOC/tHtbQduRoq1bZTV8BhBMDIvMwzWE14og7a5OGyJHbBUKvVV6Fmh SetZM7ln9AyetI1HEdAOYESBEw7x5u0= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 500A960097; Wed, 4 Mar 2026 15:13:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5B3CEC4CEF7; Wed, 4 Mar 2026 15:13:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772637233; bh=8QWqZ7YNDPVF6gZQ/i7c6RdhDtv9wD4t4d1tq0V22Gs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vPvSHVMpbDtgWdTEaP2C6BvxAyg9V9WE2471ZNAhaRLeQz/pv6ihmrNaoqAOmSBPf pVnNmTuJ7tWGqKJOQRMxgdvDSd1gsBypb43d5flxEX+PKJMg68CHlGuUIqLTiCFFuz rKc1J8WJC8Pzjhh2VbH7q/t8+THOPWP+XMsLDTbTJ56nsjnrtQHCWj3p6bIBLwDZUH dsnB+x2CRDMw3WeW5B2royvEVABcmYe086q2XeWwyM46Zbx4dnV3V7Lbti9KtpkpPj JUMdnVwEMKWupt4mteIGkGEu0zZYa8FXy9APLll3zPJtiAf8bRT1EMQssv7I9hkYG+ tPEEdQ/fLqUqQ== From: SeongJae Park 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 Subject: Re: [PATCH v4 4/5] mm: rename zone->lock to zone->_lock Date: Wed, 4 Mar 2026 07:13:34 -0800 Message-ID: <20260304151335.172572-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: EDEEAC0013 X-Stat-Signature: j76akxpbxodkwbnz5sy1c7idf7yqzewu X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1772637233-793898 X-HE-Meta: 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 ID7Fmr63 eZwerH02on+dkaOGtsNyTLhiLQ/58k/S2b1GB1MczsGbppKI6hyaenCN0L53CbYib7ewjqXeNVxZ+w0lPtXecU0mf8wVCqSTItyAzQRUDrNUwA4yxY4joxTsFF8xGAKbK/P0899H4JCrpLjEi+/AVkbPucVk7NaoVS/j0KLHHFBaVVPhUBvvhZyeN2Xl15xgPEVmdVAoWepAGkMqntAVaFiAHJud1sy6I6eX+cvJlp9lKRrlAqT8O9z2A0PVbxDfvW/l9RJrB3hRAA8PuSFx9PsiTE2pinblj/MVmEKbrlkngfI+WI+HLE/DJrX7udOxpSTIpxRU/ovDvqVa09kX2pLqPtxVzpLIlm3dRN+YjybcTbSSfKsm1v1dohRoeFa0tY9CYLezoJabknxU= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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. Thanks, SJ [...]