The patch titled
Subject: mm: page_alloc: consolidate free page accounting fix 3
has been added to the -mm mm-unstable branch. Its filename is
mm-page_alloc-consolidate-free-page-accounting-fix-3.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-consolidate-free-page-accounting-fix-3.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: page_alloc: consolidate free page accounting fix 3
Date: Tue, 9 Apr 2024 15:48:04 +0800
If the released page is captured by compaction, now the free page accounting
is not correspondingly decreased, which can make the watermark checks false
positive and result in depleted reserves etc. And I can see the false positive
watermark checks in thpcompact benchmark, that led to a slight regression:
thpcompact Percentage Faults Huge
k6.9-rc2-base base + patch10 + 2 fixes
Percentage huge-1 78.18 ( 0.00%) 71.92 ( -8.01%)
Percentage huge-3 86.70 ( 0.00%) 86.07 ( -0.73%)
Percentage huge-5 90.26 ( 0.00%) 78.02 ( -13.57%)
Percentage huge-7 92.34 ( 0.00%) 78.67 ( -14.81%)
Percentage huge-12 91.18 ( 0.00%) 81.04 ( -11.12%)
Percentage huge-18 89.00 ( 0.00%) 79.57 ( -10.60%)
Percentage huge-24 90.52 ( 0.00%) 80.07 ( -11.54%)
Percentage huge-30 94.44 ( 0.00%) 96.28 ( 1.95%)
Percentage huge-32 93.09 ( 0.00%) 99.39 ( 6.77%)
After the fix, the regression is gone.
Link: https://lkml.kernel.org/r/a2a48baca69f103aa431fd201f8a06e3b95e203d.1712648441.git.baolin.wang@xxxxxxxxxxxxxxxxx
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/mm/page_alloc.c~mm-page_alloc-consolidate-free-page-accounting-fix-3
+++ a/mm/page_alloc.c
@@ -805,8 +805,10 @@ static inline void __free_one_page(struc
while (order < MAX_PAGE_ORDER) {
int buddy_mt = migratetype;
- if (compaction_capture(capc, page, order, migratetype))
+ if (compaction_capture(capc, page, order, migratetype)) {
+ account_freepages(zone, -(1 << order), migratetype);
return;
+ }
buddy = find_buddy_page_pfn(page, pfn, order, &buddy_pfn);
if (!buddy)
_
Patches currently in -mm which might be from baolin.wang@xxxxxxxxxxxxxxxxx are
mm-page_alloc-fix-freelist-movement-during-block-conversion-fix.patch
mm-page_alloc-consolidate-free-page-accounting-fix-3.patch
mm-record-the-migration-reason-for-struct-migration_target_control.patch
mm-hugetlb-make-the-hugetlb-migration-strategy-consistent.patch
docs-hugetlbpagerst-add-hugetlb-migration-description.patch
mm-factor-out-the-numa-mapping-rebuilding-into-a-new-helper.patch
mm-support-multi-size-thp-numa-balancing.patch
mm-support-multi-size-thp-numa-balancing-v3.patch
mm-huge_memory-add-the-missing-folio_test_pmd_mappable-for-thp-split-statistics.patch
mm-page_alloc-use-the-correct-thp-order-for-thp-pcp.patch
mm-set-pageblock_order-to-hpage_pmd_order-in-case-with-config_hugetlb_page-but-thp-enabled.patch
