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 E9394456E0B for ; Wed, 23 Sep 2026 22:32:36 +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=1790202758; cv=none; b=IzTrdfdFUEVkFJQJqWUjSFwxXRljixk41cflsv2vq0AblP/L+zKECL4YUG72yYAJhB8BV7ychVbtERPIpRtT3Yq98DKrKmA3+bItGh5PySkf8ZGIfVI/NNx68dmLXS7nFFhV29ajDt4TU15b7G4Zsc/OJhkGdt3aLoEtunkm7xo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790202758; c=relaxed/simple; bh=xWFufMH0yLFZJwkvaSfF1alOsvvFFR6q7QnDePjgj3E=; h=Date:To:From:Subject:Message-Id; b=jltT1lTvbS2nKh3/asZ36TdnH95ehJlgCqtflwwpyQG8ZrZiZZj5ZGmzHc46dJTj7YuSMF2/ZKhei0xSv/o8L7YF2gxaElYe99pNIEf0R8dD4DmAO2KILsaJSs76FoNxVHit35vERd5sRR85PgS5nI80XdN+oiT2rxKb6gvB+IA= 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=l3nRQZvm; 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="l3nRQZvm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63D1B1F000FF; Wed, 23 Sep 2026 22:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1790202756; bh=Ux2WNSgmMm2netwNIljscWVcbAZglsx9YGVFsSG5nuo=; h=Date:To:From:Subject; b=l3nRQZvmZ0MrLokjSnAsx1kDCtu8MUC1jSpFhrVfgikkD6usQf60lZnlAdkSo1Cvg Z2Rrg3aJUiq3RozsQ4NFhViE76vkJ0a8v4EL3EQsr4uYhFOst4YbO61OwOzAEfyeO+ cxPCEjefqaDUSHwm1bHdHHAs1XLfVYguB70A8AHM= Date: Wed, 23 Sep 2026 15:32:36 -0700 To: mm-commits@vger.kernel.org,kasong@tencent.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-huge_memory-move-eof-trimming-into-the-file-split-helper.patch added to mm-unstable branch Message-Id: <20260923223236.63D1B1F000FF@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: move EOF trimming into the file split helper has been added to the -mm mm-unstable branch. Its filename is mm-huge_memory-move-eof-trimming-into-the-file-split-helper.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-move-eof-trimming-into-the-file-split-helper.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: move EOF trimming into the file split helper Date: Wed, 23 Sep 2026 23:32:38 +0200 Instead of receiving @end and @nr_shmem_dropped from the caller, the file split helper now computes the EOF boundary and trims pages beyond it itself, as this is only needed for file split. This drops the redundant parameter passing and sanity check. Link: https://lore.kernel.org/20260923-swap-thp-cleanup-v6-7-ba1b4ba72c6f@tencent.com Signed-off-by: Kairui Song Signed-off-by: Andrew Morton Reviewed-by: Zi Yan Acked-by: David Hildenbrand (Arm) Reviewed-by: Kiryl Shutsemau (Meta) Reviewed-by: Yeoreum Yun 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 | 41 +++++++++++++++++++---------------------- 1 file changed, 19 insertions(+), 22 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-move-eof-trimming-into-the-file-split-helper +++ a/mm/huge_memory.c @@ -4082,16 +4082,29 @@ static int __folio_freeze_split_file(str unsigned int new_order, struct page *split_at, struct xa_state *xas, struct address_space *mapping, bool do_lru, struct list_head *list, - enum split_type split_type, pgoff_t end, int *nr_shmem_dropped) + enum split_type split_type) { struct folio *end_folio = folio_next(folio); struct folio *new_folio, *next; + int nr_shmem_dropped = 0; struct lruvec *lruvec; + pgoff_t end; int ret; /* Currently device private folios can only back anonymous memory. */ VM_WARN_ON_ONCE_FOLIO(folio_is_device_private(folio), folio); + /* + * The loop below 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, + * but folio lock is good enough to serialize the trimming. + */ + end = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE); + if (shmem_mapping(mapping)) + end = shmem_fallocend(mapping->host, end); + xas_lock_irq(xas); /* @@ -4156,10 +4169,9 @@ static int __folio_freeze_split_file(str continue; } - VM_WARN_ON_ONCE(!nr_shmem_dropped); /* Drop folio beyond EOF: ->index >= end */ - if (shmem_mapping(mapping) && nr_shmem_dropped) - *nr_shmem_dropped += nr_pages; + if (shmem_mapping(mapping)) + nr_shmem_dropped += nr_pages; else if (folio_test_clear_dirty(new_folio)) folio_account_cleaned( new_folio, inode_to_wb(mapping->host)); @@ -4180,6 +4192,8 @@ static int __folio_freeze_split_file(str fail: xas_unlock_irq(xas); + if (nr_shmem_dropped) + shmem_uncharge(mapping->host, nr_shmem_dropped); return ret; } @@ -4216,9 +4230,7 @@ static int __folio_split(struct folio *f struct anon_vma *anon_vma = NULL; int old_order = folio_order(folio); struct folio *new_folio, *next; - int nr_shmem_dropped = 0; enum ttu_flags ttu_flags = 0; - pgoff_t end = 0; int ret; VM_WARN_ON_ONCE_FOLIO(!folio_test_locked(folio), folio); @@ -4295,17 +4307,6 @@ static int __folio_split(struct folio *f anon_vma = NULL; i_mmap_lock_read(mapping); - - /* - * __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, - * but folio lock is good enough to serialize the trimming. - */ - end = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE); - if (shmem_mapping(mapping)) - end = shmem_fallocend(mapping->host, end); } /* @@ -4324,11 +4325,7 @@ static int __folio_split(struct folio *f true, list, split_type); else ret = __folio_freeze_split_file(folio, new_order, split_at, &xas, mapping, - true, list, split_type, end, - &nr_shmem_dropped); - - if (nr_shmem_dropped) - shmem_uncharge(mapping->host, nr_shmem_dropped); + true, list, split_type); if (!ret && is_anon && !folio_is_device_private(folio)) ttu_flags = TTU_USE_SHARED_ZEROPAGE; _ 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