From: Lance Yang <lance.yang@linux.dev>
To: Zi Yan <ziy@nvidia.com>
Cc: linux-mm@kvack.org, Muchun Song <muchun.song@linux.dev>,
Andrew Morton <akpm@linux-foundation.org>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
"Liam R. Howlett" <liam@infradead.org>,
David Hildenbrand <david@kernel.org>,
Qi Zheng <qi.zheng@linux.dev>, Nico Pache <nico.pache@linux.dev>,
Usama Arif <usama.arif@linux.dev>,
Baolin Wang <baolin.wang@linux.alibaba.com>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>,
Lorenzo Stoakes <ljs@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Johannes Weiner <hannes@cmpxchg.org>, Dev Jain <dev.jain@arm.com>,
Barry Song <baohua@kernel.org>,
Ryan Roberts <ryan.roberts@arm.com>,
Alistair Popple <apopple@nvidia.com>,
Shakeel Butt <shakeel.butt@linux.dev>,
Kairui Song <kasong@tencent.com>,
linux-kernel@vger.kernel.org, Minchan Kim <minchan@kernel.org>,
Sergey Senozhatsky <senozhatsky@chromium.org>,
Gregory Price <gourry@gourry.net>,
Ying Huang <ying.huang@linux.alibaba.com>,
Michal Hocko <mhocko@suse.com>
Subject: Re: [PATCH v5 01/17] mm/zsmalloc: replace PG_private with pointer comparison
Date: Mon, 21 Sep 2026 14:02:27 +0800 [thread overview]
Message-ID: <58fee197-7baa-4507-948e-13b58bc3c6fa@linux.dev> (raw)
In-Reply-To: <20260920-remove-pg_private-v5-1-bb68b6a21869@nvidia.com>
On 2026/9/21 10:27, Zi Yan wrote:
> zsmalloc uses PG_private to indicate first zpdesc in a zspage chain. It is
> equivalent to check zpdesc == zspage->first_zpdesc. Replace
> is_first_zpdesc() with zpdesc == zspage->first_zpdesc in obj_allocated().
>
> For get_first_zpdesc(), first_zpdesc is from zspage->first_zpdesc, so
> replace is_first_zpdesc() with first_zpdesc->zspage == zspage, the second
> requirement of a zspage chain, where all zpdescs point to the same zspage.
>
> is_first_zpdesc(), is only used in VM_BUG_ON_PAGE(), so performance impact
> should be negligible. While at it, change VM_BUG_ON() to
> VM_WARN_ON_ONCE_PAGE().
>
> It prepares for a future commit that remove PG_private.
>
> No functional change intended.
>
> Assisted-by: LLM
> To: Minchan Kim <minchan@kernel.org>
> To: Sergey Senozhatsky <senozhatsky@chromium.org>
> To: Andrew Morton <akpm@linux-foundation.org>
> Cc: linux-mm@kvack.org
> Cc: linux-kernel@vger.kernel.org
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
> Acked-by: David Hildenbrand (Arm) <david@kernel.org>
> Signed-off-by: Zi Yan <ziy@nvidia.com>
> ---
Nice work! Feel free to add:
Reviewed-by: Lance Yang <lance.yang@linux.dev>
next prev parent reply other threads:[~2026-09-21 6:02 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-21 2:27 [PATCH v5 00/17] Remove PG_private by using page/folio->private checks instead Zi Yan
2026-09-21 2:27 ` Zi Yan
2026-09-21 2:27 ` [f2fs-dev] " Zi Yan via Linux-f2fs-devel
2026-09-21 2:27 ` [PATCH v5 01/17] mm/zsmalloc: replace PG_private with pointer comparison Zi Yan
2026-09-21 6:02 ` Lance Yang [this message]
2026-09-21 2:27 ` [PATCH v5 02/17] perf/ring_buffer: stop using PG_private as AUX page high-order marker Zi Yan
2026-09-21 2:38 ` sashiko-bot
2026-09-21 6:19 ` Lance Yang
2026-09-21 2:27 ` [PATCH v5 03/17] xen/grant-table: stop setting PG_private on pages for grant mapping Zi Yan
2026-09-21 7:00 ` Lance Yang
2026-09-21 2:28 ` [PATCH v5 04/17] fscrypt: stop setting PG_private on bounce page Zi Yan
2026-09-21 7:03 ` Lance Yang
2026-09-21 2:28 ` [PATCH v5 05/17] mm/hugetlb: use direct assignment instead of folio_change_private() Zi Yan
2026-09-21 7:11 ` Lance Yang
2026-09-21 2:28 ` [f2fs-dev] [PATCH v5 06/17] f2fs: stop using PG_private Zi Yan via Linux-f2fs-devel
2026-09-21 2:28 ` Zi Yan
2026-09-21 7:24 ` [f2fs-dev] " Lance Yang
2026-09-21 7:24 ` Lance Yang
2026-09-21 2:28 ` [f2fs-dev] [PATCH v5 07/17] f2fs: convert the ->private flag helpers to folio-only Zi Yan via Linux-f2fs-devel
2026-09-21 2:28 ` Zi Yan
2026-09-21 7:39 ` [f2fs-dev] " Lance Yang
2026-09-21 7:39 ` Lance Yang
2026-09-30 8:19 ` [f2fs-dev] " Chao Yu via Linux-f2fs-devel
2026-09-30 8:19 ` Chao Yu
2026-09-21 2:28 ` [PATCH v5 08/17] erofs: mm/pagemap: add readahead_folio_last() to avoid folio->private Zi Yan
2026-09-21 8:20 ` Lance Yang
2026-09-21 2:28 ` [PATCH v5 09/17] erofs: use folio_attach/detach_private() instead of direct assignment Zi Yan
2026-09-21 8:45 ` Lance Yang
2026-09-21 2:28 ` [PATCH v5 10/17] mm/page-flags: check page/folio->private instead of PG_private Zi Yan
2026-09-21 2:44 ` sashiko-bot
2026-09-21 15:38 ` Zi Yan
2026-09-22 1:23 ` Zi Yan
2026-09-21 9:22 ` David Hildenbrand (Arm)
2026-09-21 2:28 ` [PATCH v5 11/17] treewide: remove folio_set/clear_private() usage Zi Yan
2026-09-21 2:28 ` [PATCH v5 12/17] ceph: replace PagePrivate() with page_private() Zi Yan
2026-09-21 2:28 ` [PATCH v5 13/17] md: Use folio_alloc_buffers() Zi Yan
2026-09-21 9:23 ` David Hildenbrand (Arm)
2026-09-21 2:28 ` [PATCH v5 14/17] md: Use folio APIs in free_page() Zi Yan
2026-09-21 2:28 ` [PATCH v5 15/17] md: Remove the last use of page_buffers() Zi Yan
2026-09-21 2:28 ` [PATCH v5 16/17] treewide: remove PagePrivate() and PG_private from comments and docs Zi Yan
2026-09-21 2:28 ` Zi Yan
2026-09-21 2:28 ` [PATCH v5 17/17] mm/page-flags: remove PG_private Zi Yan
2026-09-21 2:55 ` sashiko-bot
2026-09-21 15:36 ` Zi Yan
2026-09-21 4:08 ` [PATCH v5 00/17] Remove PG_private by using page/folio->private checks instead Andrew Morton
2026-09-21 4:08 ` Andrew Morton
2026-09-21 4:08 ` [f2fs-dev] " Andrew Morton
2026-09-22 4:16 ` Nanzhe Zhao
2026-09-22 4:16 ` Nanzhe Zhao
2026-09-22 4:16 ` [f2fs-dev] " Nanzhe Zhao
2026-09-22 15:31 ` Jaegeuk Kim
2026-09-22 15:31 ` Jaegeuk Kim
2026-09-22 15:31 ` Jaegeuk Kim via Linux-f2fs-devel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=58fee197-7baa-4507-948e-13b58bc3c6fa@linux.dev \
--to=lance.yang@linux.dev \
--cc=akpm@linux-foundation.org \
--cc=apopple@nvidia.com \
--cc=baohua@kernel.org \
--cc=baolin.wang@linux.alibaba.com \
--cc=david@kernel.org \
--cc=dev.jain@arm.com \
--cc=gourry@gourry.net \
--cc=hannes@cmpxchg.org \
--cc=kasong@tencent.com \
--cc=liam@infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=ljs@kernel.org \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
--cc=muchun.song@linux.dev \
--cc=nico.pache@linux.dev \
--cc=qi.zheng@linux.dev \
--cc=rppt@kernel.org \
--cc=ryan.roberts@arm.com \
--cc=senozhatsky@chromium.org \
--cc=shakeel.butt@linux.dev \
--cc=surenb@google.com \
--cc=usama.arif@linux.dev \
--cc=vbabka@kernel.org \
--cc=willy@infradead.org \
--cc=ying.huang@linux.alibaba.com \
--cc=ziy@nvidia.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.