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mm-simplify-and-rename-mm-flags-function-for-clarity.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Nov 29, 2025

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The quilt patch titled
Subject: mm: simplify and rename mm flags function for clarity
has been removed from the -mm tree. Its filename was
mm-simplify-and-rename-mm-flags-function-for-clarity.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: Lorenzo Stoakes <[email protected]>
Subject: mm: simplify and rename mm flags function for clarity
Date: Tue, 25 Nov 2025 10:01:00 +0000

The __mm_flags_set_word() function is slightly ambiguous - we use 'set' to refer to setting individual bits (such as in mm_flags_set()) but here we use it to refer to overwriting the value altogether.

Rename it to __mm_flags_overwrite_word() to eliminate this ambiguity.

We additionally simplify the functions, eliminating unnecessary bitmap_xxx() operations (the compiler would have optimised these out but it's worth being as clear as we can be here).

Link https://lkml.kernel.org/r/8f0bc556e1b90eca8ea5eba41f8d5d3f9cd7c98a.1764064557.git.lorenzo.stoakes@oracle.com open here
Signed-off-by Lorenzo Stoakes <[email protected]>
Acked-by Vlastimil Babka <[email protected]>
Reviewed-by Pedro Falcato <[email protected]>
Acked-by Alice Ryhl <[email protected]> [rust]
Cc Alex Gaynor <[email protected]>
Cc Alistair Popple <[email protected]>
Cc Andreas Hindborg <[email protected]>
Cc Axel Rasmussen <[email protected]>
Cc Baolin Wang <[email protected]>
Cc Baoquan He <[email protected]>
Cc Barry Song <[email protected]>
Cc Ben Segall <[email protected]>
Cc Björn Roy Baron <[email protected]>
Cc Boqun Feng <[email protected]>
Cc Byungchul Park <[email protected]>
Cc Chengming Zhou <[email protected]>
Cc Chris Li <[email protected]>
Cc Danilo Krummrich <[email protected]>
Cc David Hildenbrand <[email protected]>
Cc David Rientjes <[email protected]>
Cc Dev Jain <[email protected]>
Cc Dietmar Eggemann <[email protected]>
Cc Gary Guo <[email protected]>
Cc Gregory Price <[email protected]>
Cc "Huang, Ying" <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Jann Horn <[email protected]>
Cc Jason Gunthorpe <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc John Hubbard <[email protected]>
Cc Joshua Hahn <[email protected]>
Cc Juri Lelli <[email protected]>
Cc Kairui Song <[email protected]>
Cc Kees Cook <[email protected]>
Cc Kemeng Shi <[email protected]>
Cc Lance Yang <[email protected]>
Cc Leon Romanovsky <[email protected]>
Cc Liam Howlett <[email protected]>
Cc Mathew Brost <[email protected]>
Cc Matthew Wilcox (Oracle) <[email protected]>
Cc Mel Gorman <mgorman <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Miguel Ojeda <[email protected]>
Cc Mike Rapoport <[email protected]>
Cc Muchun Song <[email protected]>
Cc Nhat Pham <[email protected]>
Cc Nico Pache <[email protected]>
Cc Oscar Salvador <[email protected]>
Cc Peter Xu <[email protected]>
Cc Peter Zijlstra <[email protected]>
Cc Qi Zheng <[email protected]>
Cc Rakie Kim <[email protected]>
Cc Rik van Riel <[email protected]>
Cc Ryan Roberts <[email protected]>
Cc Shakeel Butt <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Suren Baghdasaryan <[email protected]>
Cc Trevor Gross <[email protected]>
Cc Valentin Schneider <[email protected]>
Cc Vincent Guittot <[email protected]>
Cc Wei Xu <[email protected]>
Cc xu xin <[email protected]>
Cc Yuanchu Xie <[email protected]>
Cc Zi Yan <[email protected]>
Signed-off-by Andrew Morton <[email protected]>

---

 include/linux/mm_types.h |   14 +++++---------
 kernel/fork.c            |    4 ++--
 2 files changed, 7 insertions(+), 11 deletions(-)
include/linux/mm_types.h renamed from include/linux/mm_types.h~mm-simplify-and-rename-mm-flags-function-for-clarity +5 -9
@@ -1314,15 +1314,13 @@ struct mm_struct {
 	unsigned long cpu_bitmap[];
 };
 
-/* Set the first system word of mm flags, non-atomically. */
-static inline void __mm_flags_set_word(struct mm_struct *mm, unsigned long value)
+/* Copy value to the first system word of mm flags, non-atomically. */
+static inline void __mm_flags_overwrite_word(struct mm_struct *mm, unsigned long value)
 {
-	unsigned long *bitmap = ACCESS_PRIVATE(&mm->flags, __mm_flags);
-
-	bitmap_copy(bitmap, &value, BITS_PER_LONG);
+	*ACCESS_PRIVATE(&mm->flags, __mm_flags) = value;
 }
 
-/* Obtain a read-only view of the bitmap. */
+/* Obtain a read-only view of the mm flags bitmap. */
 static inline const unsigned long *__mm_flags_get_bitmap(const struct mm_struct *mm)
 {
 	return (const unsigned long *)ACCESS_PRIVATE(&mm->flags, __mm_flags);

@@ -1331,9 +1329,7 @@ static inline const unsigned long *__mm_
 /* Read the first system word of mm flags, non-atomically. */
 static inline unsigned long __mm_flags_get_word(const struct mm_struct *mm)
 {
-	const unsigned long *bitmap = __mm_flags_get_bitmap(mm);
-
-	return bitmap_read(bitmap, 0, BITS_PER_LONG);
+	return *__mm_flags_get_bitmap(mm);
 }
 
 /*
kernel/fork.c renamed from kernel/fork.c~mm-simplify-and-rename-mm-flags-function-for-clarity +2 -2
@@ -1061,10 +1061,10 @@ static struct mm_struct *mm_init(struct
 	if (current->mm) {
 		unsigned long flags = __mm_flags_get_word(current->mm);
 
-		__mm_flags_set_word(mm, mmf_init_legacy_flags(flags));
+		__mm_flags_overwrite_word(mm, mmf_init_legacy_flags(flags));
 		mm->def_flags = current->mm->def_flags & VM_INIT_DEF_MASK;
 	} else {
-		__mm_flags_set_word(mm, default_dump_filter);
+		__mm_flags_overwrite_word(mm, default_dump_filter);
 		mm->def_flags = 0;
 	}

_

Patches currently in -mm which might be from [email protected] are