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Date: Mon, 14 Sep 2026 17:45:33 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: kasong@tencent.com
Cc: Kairui Song via B4 Relay <devnull+kasong.tencent.com@kernel.org>,
 linux-mm@kvack.org, linux-kernel@vger.kernel.org, David Hildenbrand
 <david@kernel.org>, Lorenzo Stoakes <ljs@kernel.org>, Zi Yan
 <ziy@nvidia.com>, Baolin Wang <baolin.wang@linux.alibaba.com>,
 "Liam R. Howlett" <liam@infradead.org>, Nico Pache <nico.pache@linux.dev>,
 Ryan Roberts <ryan.roberts@arm.com>, Dev Jain <dev.jain@arm.com>, Lance
 Yang <lance.yang@linux.dev>, Usama Arif <usama.arif@linux.dev>, Vlastimil
 Babka <vbabka@kernel.org>, Mike Rapoport <rppt@kernel.org>, Suren
 Baghdasaryan <surenb@google.com>, Michal Hocko <mhocko@suse.com>, Chris Li
 <chrisl@kernel.org>, Kemeng Shi <shikemeng@huaweicloud.com>, Nhat Pham
 <nphamcs@gmail.com>, Baoquan He <baoquan.he@linux.dev>, Barry Song
 <baohua@kernel.org>, Youngjun Park <youngjun.park@lge.com>, Yeoreum Yun
 <yeoreum.yun@arm.com>, "Kiryl Shutsemau (Meta)" <kas@kernel.org>, Shivam
 Kalra <shivamkalra98@zohomail.in>, Kairui Song <ryncsn@gmail.com>
Subject: Re: [PATCH v5 00/17] mm/huge_memory: clean up and decouple the anon
 and file split helpers
Message-Id: <20260914174533.6b5dba602fb66209a700df09@linux-foundation.org>
In-Reply-To: <20260915-swap-thp-cleanup-v5-0-39878b37dfb0@tencent.com>
References: <20260915-swap-thp-cleanup-v5-0-39878b37dfb0@tencent.com>
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On Tue, 15 Sep 2026 01:14:41 +0800 Kairui Song via B4 Relay <devnull+kasong.tencent.com@kernel.org> wrote:

> The folio split path handles anon, page cache and swap cache folios in
> one routine.  That mixing is what makes the swap cache split
> restrictions hard to lift and to review. We now support uniform split to
> order-0 only, and no mappingless swap cache folios. And it has left a fair
> number of dead or redundant checks behind.
> 
> This series prepares for lifting those restrictions by cleaning up the
> code first: split the routine into an anon and a file helper, and keep
> all swap cache handling in the anon helper.  The file helper never sees
> a swap cache folio, folio_check_splittable() rejects them up front.
> 
> Apart from two bug fixes (patch 1 and 2) and a slight adjustment of anon
> splitting (patch 12), this is a pure cleanup.

Thanks, all queued up in mm.git's mm-new branch.