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: Fri, 29 Sep 2023 12:44:13 +0100
In preparation for anonymous large 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/20230929114421.3761121-3-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: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Itaru Kitayama <itaru.kitayama@xxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/rmap.c | 26 ++++++++++++++++++++------
1 file changed, 20 insertions(+), 6 deletions(-)
--- a/mm/rmap.c~mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap
+++ a/mm/rmap.c
@@ -1321,26 +1321,40 @@ 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);
}
_
Patches currently in -mm which might be from ryan.roberts@xxxxxxx are
mm-hugetlb-add-huge-page-size-param-to-set_huge_pte_at.patch
arm64-hugetlb-fix-set_huge_pte_at-to-work-with-all-swap-entries.patch
mm-allow-deferred-splitting-of-arbitrary-anon-large-folios.patch
mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.patch
mm-thp-account-pte-mapped-anonymous-thp-usage.patch
mm-thp-introduce-anon_orders-and-anon_always_mask-sysfs-files.patch
mm-thp-extend-thp-to-allocate-anonymous-large-folios.patch
mm-thp-add-recommend-option-for-anon_orders.patch
arm64-mm-override-arch_wants_pte_order.patch
selftests-mm-cow-generalize-do_run_with_thp-helper.patch
selftests-mm-cow-add-tests-for-small-order-anon-thp.patch
