The patch titled Subject: mm: non-pmd-mappable, large folios for folio_add_new_anon_rmap() has been added to the -mm mm-unstable branch. Its filename is mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.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: Ryan Roberts <ryan.roberts@xxxxxxx> Subject: mm: non-pmd-mappable, large folios for folio_add_new_anon_rmap() Date: Thu, 10 Aug 2023 15:29:39 +0100 In preparation for LARGE_ANON_FOLIO support, improve folio_add_new_anon_rmap() to allow a non-pmd-mappable, large folio to be passed to it. In this case, all contained pages are accounted using the order-0 folio (or base page) scheme. Link: https://lkml.kernel.org/r/20230810142942.3169679-3-ryan.roberts@xxxxxxx Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx> Reviewed-by: Yu Zhao <yuzhao@xxxxxxxxxx> Reviewed-by: Yin Fengwei <fengwei.yin@xxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Huang, Ying <ying.huang@xxxxxxxxx> Cc: Itaru Kitayama <itaru.kitayama@xxxxxxxxx> Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Yang Shi <shy828301@xxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/rmap.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) --- a/mm/rmap.c~mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap +++ a/mm/rmap.c @@ -1266,31 +1266,44 @@ void page_add_anon_rmap(struct page *pag * This means the inc-and-test can be bypassed. * The folio does not have to be locked. * - * If the folio is large, it is accounted as a THP. As the folio + * If the folio is pmd-mappable, it is accounted as a THP. As the folio * is new, it's assumed to be mapped exclusively by a single process. */ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, unsigned long address) { - int nr; + int nr = folio_nr_pages(folio); - VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); + VM_BUG_ON_VMA(address < vma->vm_start || + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); __folio_set_swapbacked(folio); - if (likely(!folio_test_pmd_mappable(folio))) { + if (likely(!folio_test_large(folio))) { /* increment count (starts at -1) */ atomic_set(&folio->_mapcount, 0); - nr = 1; + __page_set_anon_rmap(folio, &folio->page, vma, address, 1); + } else if (!folio_test_pmd_mappable(folio)) { + int i; + + for (i = 0; i < nr; i++) { + struct page *page = folio_page(folio, i); + + /* increment count (starts at -1) */ + atomic_set(&page->_mapcount, 0); + __page_set_anon_rmap(folio, page, vma, + address + (i << PAGE_SHIFT), 1); + } + + atomic_set(&folio->_nr_pages_mapped, nr); } else { /* increment count (starts at -1) */ atomic_set(&folio->_entire_mapcount, 0); atomic_set(&folio->_nr_pages_mapped, COMPOUND_MAPPED); - nr = folio_nr_pages(folio); + __page_set_anon_rmap(folio, &folio->page, vma, address, 1); __lruvec_stat_mod_folio(folio, NR_ANON_THPS, nr); } __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); - __page_set_anon_rmap(folio, &folio->page, vma, address, 1); } /** _ Patches currently in -mm which might be from ryan.roberts@xxxxxxx are selftests-line-buffer-test-programs-stdout.patch selftests-line-buffer-test-programs-stdout-fix.patch selftests-mm-skip-soft-dirty-tests-on-arm64.patch selftests-mm-enable-mrelease_test-for-arm64.patch selftests-mm-fix-thuge-gen-test-bugs.patch selftests-mm-va_high_addr_switch-should-skip-unsupported-arm64-configs.patch selftests-mm-make-migration-test-robust-to-failure.patch selftests-mm-optionally-pass-duration-to-transhuge-stress.patch selftests-mm-run-all-tests-from-run_vmtestssh.patch mm-allow-deferred-splitting-of-arbitrary-large-anon-folios.patch mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.patch mm-large_anon_folio-for-improved-performance.patch selftests-mm-cow-generalize-do_run_with_thp-helper.patch selftests-mm-cow-add-large-anon-folio-tests.patch