+ maple_tree-remove-maple_big_nodeparent.patch added to mm-unstable branch

+ maple_tree-remove-maple_big_nodeparent.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: maple_tree: remove maple_big_node.parent
has been added to the -mm mm-unstable branch.  Its filename is
     maple_tree-remove-maple_big_nodeparent.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-remove-maple_big_nodeparent.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: Wei Yang <richard.weiyang@gmail.com>
Subject: maple_tree: remove maple_big_node.parent
Date: Sun, 8 Sep 2024 14:05:53 +0000

Patch series "Reduce the space to be cleared for maple_big_node", v2.

Found current code may clear maple_big_node redundantly.

First we define a field parent, which is never used.  After removing this,
we reduce the size of memory to be cleared by memset.

Then mast_fill_bnode() clears part of the structure twice, since slot and
gap share some space.  By clearing the whole structure, we can avoid this.


This patch (of 2):

The member parent of maple_big_node is never used.

Let's remove it which could reduce the number of space to be cleared on
memset.

Link: https://lkml.kernel.org/r/20240908140554.20378-1-richard.weiyang@gmail.com
Link: https://lkml.kernel.org/r/20240908140554.20378-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/lib/maple_tree.c~maple_tree-remove-maple_big_nodeparent
+++ a/lib/maple_tree.c
@@ -120,7 +120,6 @@ static const unsigned char mt_min_slots[
 #define MAPLE_BIG_NODE_GAPS	(MAPLE_ARANGE64_SLOTS * 2 + 1)
 
 struct maple_big_node {
-	struct maple_pnode *parent;
 	unsigned long pivot[MAPLE_BIG_NODE_SLOTS - 1];
 	union {
 		struct maple_enode *slot[MAPLE_BIG_NODE_SLOTS];
_

Patches currently in -mm which might be from richard.weiyang@gmail.com are

maple_tree-i-is-always-less-than-or-equal-to-mas_end.patch
maple_tree-goto-complete-directly-on-a-pivot-of-0.patch
maple_tree-remove-maple_big_nodeparent.patch
maple_tree-memset-maple_big_node-as-a-whole.patch