The patch titled Subject: mm: khugepaged: support shmem mTHP copy has been added to the -mm mm-unstable branch. Its filename is mm-khugepaged-support-shmem-mthp-copy.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-khugepaged-support-shmem-mthp-copy.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 the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> Subject: mm: khugepaged: support shmem mTHP copy Date: Tue, 20 Aug 2024 17:49:15 +0800 Iterate each subpage in the large folio to copy, as preparation for supporting shmem mTHP collapse. Link: https://lkml.kernel.org/r/222d615b7c837eabb47a238126c5fdeff8aa5283.1724140601.git.baolin.wang@xxxxxxxxxxxxxxxxx Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> Cc: Barry Song <21cnbao@xxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Ryan Roberts <ryan.roberts@xxxxxxx> Cc: Yang Shi <shy828301@xxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/khugepaged.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/mm/khugepaged.c~mm-khugepaged-support-shmem-mthp-copy +++ a/mm/khugepaged.c @@ -2056,17 +2056,22 @@ xa_unlocked: index = start; dst = folio_page(new_folio, 0); list_for_each_entry(folio, &pagelist, lru) { + int i, nr_pages = folio_nr_pages(folio); + while (index < folio->index) { clear_highpage(dst); index++; dst++; } - if (copy_mc_highpage(dst, folio_page(folio, 0)) > 0) { - result = SCAN_COPY_MC; - goto rollback; + + for (i = 0; i < nr_pages; i++) { + if (copy_mc_highpage(dst, folio_page(folio, i)) > 0) { + result = SCAN_COPY_MC; + goto rollback; + } + index++; + dst++; } - index++; - dst++; } while (index < end) { clear_highpage(dst); _ Patches currently in -mm which might be from baolin.wang@xxxxxxxxxxxxxxxxx are mm-shmem-simplify-the-suitable-huge-orders-validation-for-tmpfs.patch mm-shmem-rename-shmem_is_huge-to-shmem_huge_global_enabled.patch mm-shmem-move-shmem_huge_global_enabled-into-shmem_allowable_huge_orders.patch mm-swap-extend-swap_shmem_alloc-to-support-batch-swap_map_shmem-flag-setting.patch mm-shmem-extend-shmem_partial_swap_usage-to-support-large-folio-swap.patch mm-filemap-use-xa_get_order-to-get-the-swap-entry-order.patch mm-shmem-use-swap_free_nr-to-free-shmem-swap-entries.patch mm-shmem-support-large-folio-allocation-for-shmem_replace_folio.patch mm-shmem-drop-folio-reference-count-using-nr_pages-in-shmem_delete_from_page_cache.patch mm-shmem-split-large-entry-if-the-swapin-folio-is-not-large.patch mm-shmem-support-large-folio-swap-out.patch mm-khugepaged-expand-the-is_refcount_suitable-to-support-file-folios.patch mm-khugepaged-use-the-number-of-pages-in-the-folio-to-check-the-reference-count.patch mm-khugepaged-support-shmem-mthp-copy.patch mm-khugepaged-support-shmem-mthp-collapse.patch selftests-mm-support-shmem-mthp-collapse-testing.patch