The patch titled
Subject: mm: page_alloc: use the correct THP order for THP PCP
has been added to the -mm mm-unstable branch. Its filename is
mm-page_alloc-use-the-correct-thp-order-for-thp-pcp.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-use-the-correct-thp-order-for-thp-pcp.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: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Subject: mm: page_alloc: use the correct THP order for THP PCP
Date: Wed, 3 Apr 2024 21:47:21 +0800
Commit 44042b449872 ("mm/page_alloc: allow high-order pages to be stored
on the per-cpu lists") extends the PCP allocator to store THP pages, and
it determines whether to cache THP pages in PCP by comparing with
pageblock_order. But the pageblock_order is not always equal to THP
order. It might also be MAX_PAGE_ORDER, which could prevent PCP from
caching THP pages.
Therefore, using HPAGE_PMD_ORDER instead to determine the need for caching
THP for PCP will fix this issue
Link: https://lkml.kernel.org/r/a25c9e14cd03907d5978b60546a69e6aa3fc2a7d.1712151833.git.baolin.wang@xxxxxxxxxxxxxxxxx
Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists")
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/mm/page_alloc.c~mm-page_alloc-use-the-correct-thp-order-for-thp-pcp
+++ a/mm/page_alloc.c
@@ -506,7 +506,7 @@ static inline unsigned int order_to_pind
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (order > PAGE_ALLOC_COSTLY_ORDER) {
- VM_BUG_ON(order != pageblock_order);
+ VM_BUG_ON(order != HPAGE_PMD_ORDER);
return NR_LOWORDER_PCP_LISTS;
}
#else
@@ -522,7 +522,7 @@ static inline int pindex_to_order(unsign
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (pindex == NR_LOWORDER_PCP_LISTS)
- order = pageblock_order;
+ order = HPAGE_PMD_ORDER;
#else
VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
#endif
@@ -535,7 +535,7 @@ static inline bool pcp_allowed_order(uns
if (order <= PAGE_ALLOC_COSTLY_ORDER)
return true;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- if (order == pageblock_order)
+ if (order == HPAGE_PMD_ORDER)
return true;
#endif
return false;
_
Patches currently in -mm which might be from baolin.wang@xxxxxxxxxxxxxxxxx are
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-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
