The patch titled Subject: mm: use folio more widely in __split_huge_page has been added to the -mm mm-unstable branch. Its filename is mm-use-folio-more-widely-in-__split_huge_page.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-use-folio-more-widely-in-__split_huge_page.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: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: use folio more widely in __split_huge_page Date: Wed, 28 Feb 2024 16:42:36 +0000 We already have a folio; use it instead of the head page where reasonable. Saves a couple of calls to compound_head() and elimimnates a few references to page->mapping. Link: https://lkml.kernel.org/r/20240228164326.1355045-1-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/huge_memory.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) --- a/mm/huge_memory.c~mm-use-folio-more-widely-in-__split_huge_page +++ a/mm/huge_memory.c @@ -2919,7 +2919,7 @@ static void __split_huge_page(struct pag if (head[i].index >= end) { struct folio *tail = page_folio(head + i); - if (shmem_mapping(head->mapping)) + if (shmem_mapping(folio->mapping)) nr_dropped++; else if (folio_test_clear_dirty(tail)) folio_account_cleaned(tail, @@ -2927,7 +2927,7 @@ static void __split_huge_page(struct pag __filemap_remove_folio(tail, NULL); folio_put(tail); } else if (!PageAnon(page)) { - __xa_store(&head->mapping->i_pages, head[i].index, + __xa_store(&folio->mapping->i_pages, head[i].index, head + i, 0); } else if (swap_cache) { __xa_store(&swap_cache->i_pages, offset + i, @@ -2948,23 +2948,23 @@ static void __split_huge_page(struct pag split_page_owner(head, order, new_order); /* See comment in __split_huge_page_tail() */ - if (PageAnon(head)) { + if (folio_test_anon(folio)) { /* Additional pin to swap cache */ - if (PageSwapCache(head)) { - page_ref_add(head, 1 + new_nr); + if (folio_test_swapcache(folio)) { + folio_ref_add(folio, 1 + new_nr); xa_unlock(&swap_cache->i_pages); } else { - page_ref_inc(head); + folio_ref_inc(folio); } } else { /* Additional pin to page cache */ - page_ref_add(head, 1 + new_nr); - xa_unlock(&head->mapping->i_pages); + folio_ref_add(folio, 1 + new_nr); + xa_unlock(&folio->mapping->i_pages); } local_irq_enable(); if (nr_dropped) - shmem_uncharge(head->mapping->host, nr_dropped); + shmem_uncharge(folio->mapping->host, nr_dropped); remap_page(folio, nr); if (folio_test_swapcache(folio)) @@ -2980,9 +2980,10 @@ static void __split_huge_page(struct pag for (i = 0; i < nr; i += new_nr) { struct page *subpage = head + i; + struct folio *new_folio = page_folio(subpage); if (subpage == page) continue; - unlock_page(subpage); + folio_unlock(new_folio); /* * Subpages may be freed if there wasn't any mapping _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are mm-support-order-1-folios-in-the-page-cache.patch mm-make-folios_put-the-basis-of-release_pages.patch mm-convert-free_unref_page_list-to-use-folios.patch mm-add-free_unref_folios.patch mm-use-folios_put-in-__folio_batch_release.patch memcg-add-mem_cgroup_uncharge_folios.patch mm-remove-use-of-folio-list-from-folios_put.patch mm-use-free_unref_folios-in-put_pages_list.patch mm-use-__page_cache_release-in-folios_put.patch mm-handle-large-folios-in-free_unref_folios.patch mm-allow-non-hugetlb-large-folios-to-be-batch-processed.patch mm-free-folios-in-a-batch-in-shrink_folio_list.patch mm-free-folios-directly-in-move_folios_to_lru.patch memcg-remove-mem_cgroup_uncharge_list.patch mm-remove-free_unref_page_list.patch mm-remove-lru_to_page.patch mm-convert-free_pages_and_swap_cache-to-use-folios_put.patch mm-use-a-folio-in-__collapse_huge_page_copy_succeeded.patch mm-convert-free_swap_cache-to-take-a-folio.patch mm-use-folio-more-widely-in-__split_huge_page.patch