The patch titled
Subject: mm/rmap: move SetPageAnonExclusive() out of page_move_anon_rmap()
has been added to the -mm mm-unstable branch. Its filename is
mm-rmap-move-setpageanonexclusive-out-of-page_move_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-rmap-move-setpageanonexclusive-out-of-page_move_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
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/rmap: move SetPageAnonExclusive() out of page_move_anon_rmap()
Date: Mon, 2 Oct 2023 16:29:47 +0200
Patch series "mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()".
Convert page_move_anon_rmap() to folio_move_anon_rmap(), letting the
callers handle PageAnonExclusive. I'm including cleanup patch #3 because
it fits into the picture and can be done cleaner by the conversion.
This patch (of 3):
Let's move it into the caller: there is a difference between whether an
anon folio can only be mapped by one process (e.g., into one VMA), and
whether it is truly exclusive (e.g., no references -- including GUP --
from other processes).
Further, for large folios the page might not actually be pointing at the
head page of the folio, so it better be handled in the caller. This is a
preparation for converting page_move_anon_rmap() to consume a folio.
Link: https://lkml.kernel.org/r/20231002142949.235104-1-david@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20231002142949.235104-2-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 1 +
mm/hugetlb.c | 4 +++-
mm/memory.c | 1 +
mm/rmap.c | 1 -
4 files changed, 5 insertions(+), 2 deletions(-)
--- a/mm/huge_memory.c~mm-rmap-move-setpageanonexclusive-out-of-page_move_anon_rmap
+++ a/mm/huge_memory.c
@@ -1506,6 +1506,7 @@ vm_fault_t do_huge_pmd_wp_page(struct vm
pmd_t entry;
page_move_anon_rmap(page, vma);
+ SetPageAnonExclusive(page);
folio_unlock(folio);
reuse:
if (unlikely(unshare)) {
--- a/mm/hugetlb.c~mm-rmap-move-setpageanonexclusive-out-of-page_move_anon_rmap
+++ a/mm/hugetlb.c
@@ -5460,8 +5460,10 @@ retry_avoidcopy:
* owner and can reuse this page.
*/
if (folio_mapcount(old_folio) == 1 && folio_test_anon(old_folio)) {
- if (!PageAnonExclusive(&old_folio->page))
+ if (!PageAnonExclusive(&old_folio->page)) {
page_move_anon_rmap(&old_folio->page, vma);
+ SetPageAnonExclusive(&old_folio->page);
+ }
if (likely(!unshare))
set_huge_ptep_writable(vma, haddr, ptep);
--- a/mm/memory.c~mm-rmap-move-setpageanonexclusive-out-of-page_move_anon_rmap
+++ a/mm/memory.c
@@ -3484,6 +3484,7 @@ static vm_fault_t do_wp_page(struct vm_f
* sunglasses. Hit it.
*/
page_move_anon_rmap(vmf->page, vma);
+ SetPageAnonExclusive(vmf->page);
folio_unlock(folio);
reuse:
if (unlikely(unshare)) {
--- a/mm/rmap.c~mm-rmap-move-setpageanonexclusive-out-of-page_move_anon_rmap
+++ a/mm/rmap.c
@@ -1165,7 +1165,6 @@ void page_move_anon_rmap(struct page *pa
* folio_test_anon()) will not see one without the other.
*/
WRITE_ONCE(folio->mapping, anon_vma);
- SetPageAnonExclusive(page);
}
/**
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-rmap-drop-stale-comment-in-page_add_anon_rmap-and-hugepage_add_anon_rmap.patch
mm-rmap-move-setpageanonexclusive-out-of-__page_set_anon_rmap.patch
mm-rmap-move-folio_test_anon-check-out-of-__folio_set_anon.patch
mm-rmap-warn-on-new-pte-mapped-folios-in-page_add_anon_rmap.patch
mm-rmap-simplify-pageanonexclusive-sanity-checks-when-adding-anon-rmap.patch
mm-rmap-simplify-pageanonexclusive-sanity-checks-when-adding-anon-rmap-fix.patch
mm-rmap-pass-folio-to-hugepage_add_anon_rmap.patch
mm-rmap-move-setpageanonexclusive-out-of-page_move_anon_rmap.patch
mm-rmap-convert-page_move_anon_rmap-to-folio_move_anon_rmap.patch
memory-move-exclusivity-detection-in-do_wp_page-into-wp_can_reuse_anon_folio.patch
