+ maple_tree-use-prefetched-value-in-mas_wr_store_type.patch added to mm-unstable branch

+ maple_tree-use-prefetched-value-in-mas_wr_store_type.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: maple_tree: use prefetched value in mas_wr_store_type()
has been added to the -mm mm-unstable branch.  Its filename is
     maple_tree-use-prefetched-value-in-mas_wr_store_type.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-use-prefetched-value-in-mas_wr_store_type.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 (Oracle)" <liam@infradead.org>
Subject: maple_tree: use prefetched value in mas_wr_store_type()
Date: Fri, 21 Aug 2026 15:26:16 -0400

The slot contents exist in wr_mas->content, which has less overhead than
reading the slot again.

Link: https://lore.kernel.org/20260821192627.4085470-9-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/maple_tree.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/lib/maple_tree.c~maple_tree-use-prefetched-value-in-mas_wr_store_type
+++ a/lib/maple_tree.c
@@ -3280,7 +3280,7 @@ static inline void mas_wr_slot_store(str
 	void __rcu **slots = wr_mas->slots;
 	bool gap = false;
 
-	gap |= !mt_slot_locked(mas->tree, slots, offset);
+	gap |= !wr_mas->content;
 	gap |= !mt_slot_locked(mas->tree, slots, offset + 1);
 
 	if (wr_mas->offset_end - offset == 1) {
_

Patches currently in -mm which might be from liam@infradead.org are

maple_tree-add-rcu-locking-check-when-lockdep-is-enabled.patch
locking-lockdep-add-sequence-counter-to-held_lock.patch
maple_tree-add-write-lock-checking-with-lockdep-sequence-numbers.patch
maple_tree-documentation-fix.patch
maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch
maple_tree-drop-maple_alloc_slots.patch
maple_tree-clarify-comments-on-mas_nomem.patch
maple_tree-use-prefetched-value-in-mas_wr_store_type.patch
maple_tree-optimise-mas_wr_node_store-when-not-in-rcu-mode.patch
maple_tree-micro-optimisation-of-mas_wr_store_type.patch
maple_tree-add-bulk-parent-set-helper.patch
maple_tree-catch-race-in-mas_alloc_cyclic.patch
maple_tree-document-that-erase-may-use-gfp_kernel-for-allocations.patch
maple_tree-avoid-mas_erase-and-mtree_erase-failures.patch
maple_tree-document-erase-and-allocations-better.patch
maple_tree-change-two-gfp-flags-in-tests.patch
maple_tree-fix-argument-name-in-header.patch
maple_tree-avoid-extra-gap-calculation.patch
maple_tree-add-helper-mas_make_walkable.patch