[merged mm-stable] mm-always-inline-_compound_head-with-config_hugetlb_page_optimize_vmemmap=y.patch removed from -mm tree

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The quilt patch titled
     Subject: mm: always inline _compound_head() with CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
has been removed from the -mm tree.  Its filename was
     mm-always-inline-_compound_head-with-config_hugetlb_page_optimize_vmemmap=y.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm: always inline _compound_head() with CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
Date: Tue, 20 Aug 2024 14:22:10 +0200

We already force-inline page_fixed_fake_head(), page_is_fake_head() and
PageTail(), however the compiler might decide that _compound_head() is not
worthy to be inlined, because of page_fixed_fake_head().

The result is that, for example, PageAnonExclusive() now might involve a
function call when checking PageHuge(), which performs a
page_folio()->_compound_head() call.  This can lead to a slight regression
of the stress-ng.clone benchmark.

This is not super-urgent to fix, but always inlining _compound_head()
seems like the obvious thing to do for this primitive, similar to the
other ones.

This change restores the slight regression and a compilation with
CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y shows no relevant bloat [2]:

	add/remove: 15/14 grow/shrink: 79/87 up/down: 12836/-13917 (-1081)
	...
	Total: Before=32786363, After=32785282, chg -0.00%

[1] https://lkml.kernel.org/r/817150f2-abf7-430f-9973-540bd6cdd26f@xxxxxxxxx
[2] https://lore.kernel.org/all/116e117c-2821-401d-8e62-b85cdec37f4a@xxxxxxxxxx/

Link: https://lkml.kernel.org/r/20240820122210.660140-1-david@xxxxxxxxxx
Fixes: c0bff412e67b ("mm: allow anon exclusive check over hugetlb tail pages")
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-lkp/202407301049.5051dc19-oliver.sang@xxxxxxxxx
Tested-by: Yin Fengwei <fengwei.yin@xxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 include/linux/page-flags.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/page-flags.h~mm-always-inline-_compound_head-with-config_hugetlb_page_optimize_vmemmap=y
+++ a/include/linux/page-flags.h
@@ -232,7 +232,7 @@ static __always_inline int page_is_fake_
 	return page_fixed_fake_head(page) != page;
 }
 
-static inline unsigned long _compound_head(const struct page *page)
+static __always_inline unsigned long _compound_head(const struct page *page)
 {
 	unsigned long head = READ_ONCE(page->compound_head);
 
_

Patches currently in -mm which might be from david@xxxxxxxxxx are






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