+ maple_tree-mark-three-functions-as-__maybe_unused.patch added to mm-unstable branch

+ maple_tree-mark-three-functions-as-__maybe_unused.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: maple_tree: mark three functions as __maybe_unused
has been added to the -mm mm-unstable branch.  Its filename is
     maple_tree-mark-three-functions-as-__maybe_unused.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-mark-three-functions-as-__maybe_unused.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: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Subject: maple_tree: mark three functions as __maybe_unused
Date: Fri, 6 Sep 2024 22:15:06 -0400

People keep trying to remove three functions that are going to be used in
a feature that is being developed.  Dropping the functions entirely may
end up with people trying to use the bit for other uses, as people have
tried in the past.

Adding __maybe_unused stops compilers complaining about the unused
functions so they can be silently optimised out of the compiled code and
people won't try to claim the bit for another use.

Link: https://lore.kernel.org/all/20230726080916.17454-2-zhangpeng.00@bytedance.com/
Link: https://lore.kernel.org/all/202408310728.S7EE59BN-lkp@intel.com/
Link: https://lkml.kernel.org/r/20240907021506.4018676-1-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/maple_tree.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/lib/maple_tree.c~maple_tree-mark-three-functions-as-__maybe_unused
+++ a/lib/maple_tree.c
@@ -348,17 +348,17 @@ static inline void *mte_safe_root(const
 	return (void *)((unsigned long)node & ~MAPLE_ROOT_NODE);
 }
 
-static inline void *mte_set_full(const struct maple_enode *node)
+static inline void __maybe_unused *mte_set_full(const struct maple_enode *node)
 {
 	return (void *)((unsigned long)node & ~MAPLE_ENODE_NULL);
 }
 
-static inline void *mte_clear_full(const struct maple_enode *node)
+static inline void __maybe_unused *mte_clear_full(const struct maple_enode *node)
 {
 	return (void *)((unsigned long)node | MAPLE_ENODE_NULL);
 }
 
-static inline bool mte_has_null(const struct maple_enode *node)
+static inline bool __maybe_unused mte_has_null(const struct maple_enode *node)
 {
 	return (unsigned long)node & MAPLE_ENODE_NULL;
 }
_

Patches currently in -mm which might be from Liam.Howlett@oracle.com are

mm-damon-vaddr-protect-vma-traversal-in-__damon_va_thre_regions-with-rcu-read-lock.patch
maple_tree-mark-three-functions-as-__maybe_unused.patch