From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D2F4B318EE6 for ; Thu, 19 Mar 2026 22:17:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773958630; cv=none; b=Xq6cSD3iOLJlFWVLdsyBhTl8434orZO8TuPGaaG2iXUQFfNgbL0MHMEtWoC/vvXigQ1nAzWDcvaoioCJcHomNJVv04Ftxo7exEe22+fxdqkst+y7tDhYRzf8kpWT+BmRjkAELTlT7fWHTUXE3N//TqLb+0mHDD/sX0njidgSlyg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773958630; c=relaxed/simple; bh=9ahl8MLu04LcKE//p5ACDyYBO+fGW4N57puuD9CedbY=; h=Date:To:From:Subject:Message-Id; b=t/WPv82s+5N0Yaf5f3T06XX0WthrD5FfwjU2YJdUuRoP+G+E3rfUVPhNvdssedkpOyGLigRbupG/VnrjGWKPMbNUX/YR+u4pTwF3kqpwuq2Hj8y/gkZlaFT35txgcJeaKfuOm5m0C4rx84FdYthiM7Rk1Tto5U+LbZvYtuwfijA= 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=KurDy1f8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="KurDy1f8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 708EAC19424; Thu, 19 Mar 2026 22:17:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1773958630; bh=9ahl8MLu04LcKE//p5ACDyYBO+fGW4N57puuD9CedbY=; h=Date:To:From:Subject:From; b=KurDy1f8UWrG4HdNmTztJj0iO/S3A7tyZeneAsrN07pwSkS5BTPjTzqH9PYhv3Ls6 LPrpVc6U6vjevTh4Bf0Qcxwu+C8dGRMptlO3MLL7Ep1gaGVVP+fu48YZRlltSScVzD GfUTm95kjYPf5jYNmgdSIXDtlcn2EZkgr5IDYSQk= Date: Thu, 19 Mar 2026 15:17:09 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,zhengqi.arch@bytedance.com,surenb@google.com,ryan.roberts@arm.com,rppt@kernel.org,npache@redhat.com,mhocko@suse.com,liam.howlett@oracle.com,lance.yang@linux.dev,kirill@shutemov.name,dev.jain@arm.com,david@kernel.org,baolin.wang@linux.alibaba.com,baohua@kernel.org,ljs@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-huge_memory-deduplicate-zap_huge_pmd-further-by-tracking-state.patch added to mm-new branch Message-Id: <20260319221710.708EAC19424@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: deduplicate zap_huge_pmd() further by tracking state has been added to the -mm mm-new branch. Its filename is mm-huge_memory-deduplicate-zap_huge_pmd-further-by-tracking-state.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-deduplicate-zap_huge_pmd-further-by-tracking-state.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next 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: "Lorenzo Stoakes (Oracle)" Subject: mm/huge_memory: deduplicate zap_huge_pmd() further by tracking state Date: Thu, 19 Mar 2026 13:00:14 +0000 The flush_needed boolean is really tracking whether a PMD entry is present, so use it that way directly and rename it to is_present. Deduplicate the folio_remove_rmap_pmd() and folio map count warning between present and device private by tracking where we need to remove the rmap. We can also remove the comment about using flush_needed to track whether a PMD entry is present as it's now irrelevant. Link: https://lkml.kernel.org/r/440f68edcb597c28918d89b0be279d498561c89a.1773924928.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand (ARM) Cc: Dev Jain Cc: Lance Yang Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Nico Pache Cc: Qi Zheng Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Zi Yan Cc: Kiryl Shutsemau Signed-off-by: Andrew Morton --- mm/huge_memory.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-deduplicate-zap_huge_pmd-further-by-tracking-state +++ a/mm/huge_memory.c @@ -2337,9 +2337,10 @@ static inline void zap_deposited_table(s bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr) { + bool needs_remove_rmap = false; struct folio *folio = NULL; bool needs_deposit = false; - bool flush_needed = false; + bool is_present = false; spinlock_t *ptl; pmd_t orig_pmd; @@ -2356,6 +2357,7 @@ bool zap_huge_pmd(struct mmu_gather *tlb */ orig_pmd = pmdp_huge_get_and_clear_full(vma, addr, pmd, tlb->fullmm); + arch_check_zapped_pmd(vma, orig_pmd); tlb_remove_pmd_tlb_entry(tlb, pmd, addr); if (vma_is_special_huge(vma)) @@ -2365,17 +2367,15 @@ bool zap_huge_pmd(struct mmu_gather *tlb goto out; } - if (pmd_present(orig_pmd)) { + is_present = pmd_present(orig_pmd); + if (is_present) { folio = pmd_folio(orig_pmd); - - flush_needed = true; - folio_remove_rmap_pmd(folio, &folio->page, vma); - WARN_ON_ONCE(folio_mapcount(folio) < 0); + needs_remove_rmap = true; } else if (pmd_is_valid_softleaf(orig_pmd)) { const softleaf_t entry = softleaf_from_pmd(orig_pmd); folio = softleaf_to_folio(entry); - + needs_remove_rmap = folio_is_device_private(folio); if (!thp_migration_supported()) WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!"); } else { @@ -2390,27 +2390,25 @@ bool zap_huge_pmd(struct mmu_gather *tlb add_mm_counter(tlb->mm, mm_counter_file(folio), -HPAGE_PMD_NR); - /* - * Use flush_needed to indicate whether the PMD entry - * is present, instead of checking pmd_present() again. - */ - if (flush_needed && pmd_young(orig_pmd) && + if (is_present && pmd_young(orig_pmd) && likely(vma_has_recency(vma))) folio_mark_accessed(folio); } - if (folio_is_device_private(folio)) { + if (needs_remove_rmap) { folio_remove_rmap_pmd(folio, &folio->page, vma); WARN_ON_ONCE(folio_mapcount(folio) < 0); - folio_put(folio); } out: if (arch_needs_pgtable_deposit() || needs_deposit) zap_deposited_table(tlb->mm, pmd); + if (needs_remove_rmap && !is_present) + folio_put(folio); + spin_unlock(ptl); - if (flush_needed) + if (is_present) tlb_remove_page_size(tlb, &folio->page, HPAGE_PMD_SIZE); return true; } _ Patches currently in -mm which might be from ljs@kernel.org are mm-zswap-add-missing-kunmap_local.patch mm-rmap-clear-vma-anon_vma-on-error.patch mm-rename-vma-flag-helpers-to-be-more-readable.patch mm-add-vma_desc_test_all-and-use-it.patch mm-always-inline-__mk_vma_flags-and-invoked-functions.patch mm-reintroduce-vma_flags_test-as-a-singular-flag-test.patch mm-reintroduce-vma_desc_test-as-a-singular-flag-test.patch tools-testing-vma-add-test-for-vma_flags_test-vma_desc_test.patch tools-testing-vma-add-test-for-vma_flags_test-vma_desc_test-fix.patch mm-mremap-correct-invalid-map-count-check.patch mm-abstract-reading-sysctl_max_map_count-and-read_once.patch mm-mremap-check-map-count-under-mmap-write-lock-and-abstract.patch mm-vma-add-vma_flags_empty-vma_flags_and-vma_flags_diff_pair.patch tools-testing-vma-add-unit-tests-flag-empty-diff_pair-and.patch mm-vma-add-further-vma_flags_t-unions.patch tools-testing-vma-convert-bulk-of-test-code-to-vma_flags_t.patch mm-vma-use-new-vma-flags-for-sticky-flags-logic.patch tools-testing-vma-fix-vma-flag-tests.patch mm-vma-add-append_vma_flags-helper.patch tools-testing-vma-add-simple-test-for-append_vma_flags.patch mm-unexport-vm_brk_flags-and-eliminate-vm_flags-parameter.patch mm-vma-introduce-vma_flags_same.patch mm-vma-introduce-_to_-helpers.patch tools-testing-vma-test-that-legacy-flag-helpers-work-correctly.patch mm-vma-introduce-vma_test-and-make-inlining-consistent.patch tools-testing-vma-update-vma-flag-tests-to-test-vma_test.patch mm-introduce-vma_flags_count-and-vma_test_single_mask.patch tools-testing-vma-test-vma_flags_countvma_test_single_mask.patch mm-convert-do_brk_flags-to-use-vma_flags_t.patch mm-update-vma_supports_mlock-to-use-new-vma-flags.patch mm-vma-introduce-vma_clear_flags.patch tools-testing-vma-update-vma-tests-to-test-vma_clear_flags.patch mm-vma-convert-as-much-as-we-can-in-mm-vmac-to-vma_flags_t.patch mm-vma-convert-vma_modify_flags-to-use-vma_flags_t.patch mm-vma-convert-__mmap_region-to-use-vma_flags_t.patch mm-various-small-mmap_prepare-cleanups.patch mm-add-documentation-for-the-mmap_prepare-file-operation-callback.patch mm-document-vm_operations_struct-open-the-same-as-close.patch mm-add-vm_ops-mapped-hook.patch fs-afs-correctly-drop-reference-count-on-mapping-failure.patch mm-add-mmap_action_simple_ioremap.patch misc-open-dice-replace-deprecated-mmap-hook-with-mmap_prepare.patch hpet-replace-deprecated-mmap-hook-with-mmap_prepare.patch mtdchar-replace-deprecated-mmap-hook-with-mmap_prepare-clean-up.patch stm-replace-deprecated-mmap-hook-with-mmap_prepare.patch staging-vme_user-replace-deprecated-mmap-hook-with-mmap_prepare.patch mm-allow-handling-of-stacked-mmap_prepare-hooks-in-more-drivers.patch drivers-hv-vmbus-replace-deprecated-mmap-hook-with-mmap_prepare.patch uio-replace-deprecated-mmap-hook-with-mmap_prepare-in-uio_info.patch mm-add-mmap_action_map_kernel_pages.patch mm-on-remap-assert-that-input-range-within-the-proposed-vma.patch mm-huge_memory-simplify-vma_is_specal_huge.patch mm-huge-avoid-big-else-branch-in-zap_huge_pmd.patch mm-huge_memory-have-zap_huge_pmd-return-a-boolean-add-kdoc.patch mm-huge_memory-handle-buggy-pmd-entry-in-zap_huge_pmd.patch mm-huge_memory-add-a-common-exit-path-to-zap_huge_pmd.patch mm-huge_memory-remove-unnecessary-vm_bug_on_page.patch mm-huge_memory-deduplicate-zap-deposited-table-call.patch mm-huge_memory-deduplicate-zap_huge_pmd-further-by-tracking-state.patch mm-huge_memory-have-zap_huge_pmd-use-vm_normal_folio_pmd.patch