From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 0E981469845 for ; Wed, 23 Sep 2026 22:32:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790202755; cv=none; b=ga+lPMEpusDwhpG4M32QgMc/ffGJJLqmEJupuEJRMwts63QEKQolJxLp+As86fluLFpIeuttzSXL3Adnb6kEGVZ8tihXYWAZxbmSZqGKrvwHatEACkXuyq84Ma9PyAOgPPGReK7pWSdnqEOcDzqBRHjm8k8BKAxveIU+kzPe9Sg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790202755; c=relaxed/simple; bh=tNMhRve/YWJyaiMurj9dsh9fTzRcRRvr229K0Hp8mb0=; h=Date:To:From:Subject:Message-Id; b=OtvRTWkLrY5oAGebYv2lq/o1/J+mcBnvnWyX04y4FWCitste1lF0rmRPuxsgCfasyU4ziNhrQj0PdPN2vn3FoWc9ORL5JXjBabtSTKrgAHmVBD7JWj2e9/bMt/hbBvpkMqhKHlzFiwY0kDHW7+Ws3ij7VFQ6adRhi3WXW+bZRB0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=ccXa45af; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="ccXa45af" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 82E861F000FF; Wed, 23 Sep 2026 22:32:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1790202752; bh=IJWSGhVimISy3Q6jyIScS0SNtZ00UBFmxGZCFuW2lWs=; h=Date:To:From:Subject; b=ccXa45af+iiTcnlQy8kTP207UJMY8skr00Nsw3z7tpVa5H/GQi99Et/JG2slHUL/f DD19zCTgIDziyF2k+XSN92/W6o2G3Ukfq6JOHzlB+3f7PhenXK+vRjUNJtbsrYb1Zg vcobY2PjebXdT8MilOsyu8CBmk7WiC2AKhaqkCjU= Date: Wed, 23 Sep 2026 15:32:32 -0700 To: mm-commits@vger.kernel.org,kasong@tencent.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-huge_memory-rename-__split_unmapped_folio-to-__split_frozen_folio.patch added to mm-unstable branch Message-Id: <20260923223232.82E861F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/huge_memory: rename __split_unmapped_folio() to __split_frozen_folio() has been added to the -mm mm-unstable branch. Its filename is mm-huge_memory-rename-__split_unmapped_folio-to-__split_frozen_folio.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-huge_memory-rename-__split_unmapped_folio-to-__split_frozen_folio.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Kairui Song Subject: mm/huge_memory: rename __split_unmapped_folio() to __split_frozen_folio() Date: Wed, 23 Sep 2026 23:32:36 +0200 The helper splits a folio whose refcount is frozen: the frozen refcount is the state it relies on, while unmapping is arranged by the caller beforehand. The old name caused confusion and people may try to call the helper on non-frozen folios. Also add a VM_WARN_ON_ONCE_FOLIO(folio_mapped(folio)) to self document that frozen implies unmapped. Link: https://lore.kernel.org/20260923-swap-thp-cleanup-v6-5-ba1b4ba72c6f@tencent.com Signed-off-by: Kairui Song Signed-off-by: Andrew Morton Suggested-by: Zi Yan Reviewed-by: Zi Yan Reviewed-by: Yeoreum Yun Reviewed-by: Kiryl Shutsemau (Meta) Acked-by: David Hildenbrand (Arm) Cc: Lorenzo Stoakes Cc: Baolin Wang Cc: Liam R. Howlett Cc: Nico Pache Cc: Ryan Roberts Cc: Dev Jain Cc: Lance Yang Cc: Usama Arif Cc: Vlastimil Babka Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Michal Hocko Cc: Chris Li Cc: Kemeng Shi Cc: Nhat Pham Cc: Baoquan He Cc: Barry Song Cc: Youngjun Park Cc: Shivam Kalra Cc: Kairui Song --- mm/huge_memory.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-rename-__split_unmapped_folio-to-__split_frozen_folio +++ a/mm/huge_memory.c @@ -3810,8 +3810,8 @@ static void __split_folio_to_order(struc } /** - * __split_unmapped_folio() - splits an unmapped @folio to lower order folios in - * two ways: uniform split or non-uniform split. + * __split_frozen_folio() - splits a frozen @folio to lower order folios + * in two ways: uniform split or non-uniform split. * @folio: the to-be-split folio * @new_order: the smallest order of the after split folios (since buddy * allocator like split generates folios with orders from @folio's @@ -3850,7 +3850,7 @@ static void __split_folio_to_order(struc * Return: 0 - successful, <0 - failed (if -ENOMEM is returned, @folio might be * split but not to @new_order, the caller needs to check) */ -static int __split_unmapped_folio(struct folio *folio, int new_order, +static int __split_frozen_folio(struct folio *folio, int new_order, struct page *split_at, struct xa_state *xas, struct address_space *mapping, enum split_type split_type) { @@ -3860,6 +3860,9 @@ static int __split_unmapped_folio(struct struct folio *old_folio = folio; int split_order; + /* Frozen implies unmapped, callers unmap before splitting. */ + VM_WARN_ON_ONCE_FOLIO(folio_mapped(folio), folio); + /* * split to new_order one order at a time. For uniform split, * folio is split to new_order directly. @@ -4037,8 +4040,8 @@ static int __folio_freeze_split_anon(str if (do_lru) lruvec = folio_lruvec_lock(folio); - ret = __split_unmapped_folio(folio, new_order, split_at, NULL, - NULL, split_type); + ret = __split_frozen_folio(folio, new_order, split_at, NULL, + NULL, split_type); /* * Unfreeze the after-split folios and put them back to the right @@ -4104,8 +4107,8 @@ static int __folio_freeze_split_file(str if (do_lru) lruvec = folio_lruvec_lock(folio); - ret = __split_unmapped_folio(folio, new_order, split_at, xas, - mapping, split_type); + ret = __split_frozen_folio(folio, new_order, split_at, xas, + mapping, split_type); /* * Unfreeze after-split folios and put them back to the right @@ -4169,9 +4172,9 @@ static int __folio_freeze_split_file(str * @list: after-split folios will be put on it if non NULL * @split_type: perform uniform split or not (non-uniform split) * - * It calls __split_unmapped_folio() to perform uniform and non-uniform split. + * It calls __split_frozen_folio() to perform uniform and non-uniform split. * It is in charge of checking whether the split is supported or not and - * preparing @folio for __split_unmapped_folio(). + * preparing @folio for __split_frozen_folio(). * * After splitting, the after-split folio containing @lock_at remains locked * and others are unlocked: @@ -4274,7 +4277,7 @@ static int __folio_split(struct folio *f i_mmap_lock_read(mapping); /* - *__split_unmapped_folio() may need to trim off pages beyond + * __split_frozen_folio() may need to trim off pages beyond * EOF: but on 32-bit, i_size_read() takes an irq-unsafe * seqlock, which cannot be nested inside the page tree lock. * So note end now: i_size itself may be changed at any moment, _ Patches currently in -mm which might be from kasong@tencent.com are mm-memcontrol-move-the-lru_zone_size-sanity-check-to-the-reader-side.patch mm-mglru-introduce-helpers-for-manipulating-gen-and-refs-flags.patch mm-migrate-copy-all-referenced-state-via-folio_migrate_lru_refs.patch mm-mglru-move-max_seq-read-into-walk_update_folio.patch mm-mglru-use-explicit-tier-range-in-read_ctrl_pos.patch mm-mglru-fix-potential-generation-folio-number-leak.patch mm-swap-fix-off-by-one-in-swap-cache-replace-sanity-check.patch mm-huge_memory-fix-rejection-of-swap-cache-folios-with-a-mapping.patch mm-huge_memory-invert-folio_ref_freeze-check-to-reduce-indentation.patch mm-huge_memory-split-the-routine-for-splitting-anon-and-file-folio.patch mm-huge_memory-rename-__split_unmapped_folio-to-__split_frozen_folio.patch mm-huge_memory-consolidate-irq-and-locking-for-folio-split.patch mm-huge_memory-move-eof-trimming-into-the-file-split-helper.patch mm-huge_memory-move-unmap-and-remap-into-the-split-helpers.patch mm-huge_memory-rename-remap_page-to-remap_anon_folio.patch mm-huge_memory-move-the-racy-refcount-check-into-unmap_folio.patch mm-huge_memory-move-filemap-management-into-the-file-split-helper.patch mm-huge_memory-move-anon_vma-handling-into-the-anon-split-helper.patch mm-huge_memory-move-memcg-switch-into-the-file-split-helper.patch mm-huge_memory-drop-the-unused-do_lru-argument-of-the-file-split-helper.patch mm-huge_memory-clean-up-after-split-folio-freeing-in-__folio_split.patch mm-huge_memory-count-only-swap-cache-refs-in-anon-folio-split.patch mm-huge_memory-drop-the-redundant-mapping-argument-of-__split_frozen_folio.patch