The quilt patch titled
Subject: maple_tree: avoid unnecessary ascending
has been removed from the -mm tree. Its filename was
maple_tree-avoid-unnecessary-ascending.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: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Subject: maple_tree: avoid unnecessary ascending
Date: Thu, 18 May 2023 10:55:12 -0400
The maple tree node limits are implied by the parent. When walking up the
tree, the limit may not be known until a slot that does not have implied
limits are encountered. However, if the node is the left-most or
right-most node, the walking up to find that limit can be skipped.
This commit also fixes the debug/testing code that was not setting the
limit on walking down the tree as that optimization is not compatible with
this change.
Link: https://lkml.kernel.org/r/20230518145544.1722059-4-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Reviewed-by: Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>
Cc: David Binderman <dcb314@xxxxxxxxxxx>
Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Vernon Yang <vernon2gm@xxxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/maple_tree.c | 11 ++++++++---
tools/testing/radix-tree/maple.c | 4 ++++
2 files changed, 12 insertions(+), 3 deletions(-)
--- a/lib/maple_tree.c~maple_tree-avoid-unnecessary-ascending
+++ a/lib/maple_tree.c
@@ -1103,7 +1103,6 @@ static int mas_ascend(struct ma_state *m
enum maple_type a_type;
unsigned long min, max;
unsigned long *pivots;
- unsigned char offset;
bool set_max = false, set_min = false;
a_node = mas_mn(mas);
@@ -1115,8 +1114,9 @@ static int mas_ascend(struct ma_state *m
p_node = mte_parent(mas->node);
if (unlikely(a_node == p_node))
return 1;
+
a_type = mas_parent_type(mas, mas->node);
- offset = mte_parent_slot(mas->node);
+ mas->offset = mte_parent_slot(mas->node);
a_enode = mt_mk_node(p_node, a_type);
/* Check to make sure all parent information is still accurate */
@@ -1124,7 +1124,6 @@ static int mas_ascend(struct ma_state *m
return 1;
mas->node = a_enode;
- mas->offset = offset;
if (mte_is_root(a_enode)) {
mas->max = ULONG_MAX;
@@ -1132,6 +1131,12 @@ static int mas_ascend(struct ma_state *m
return 0;
}
+ if (!mas->min)
+ set_min = true;
+
+ if (mas->max == ULONG_MAX)
+ set_max = true;
+
min = 0;
max = ULONG_MAX;
do {
--- a/tools/testing/radix-tree/maple.c~maple_tree-avoid-unnecessary-ascending
+++ a/tools/testing/radix-tree/maple.c
@@ -35259,6 +35259,7 @@ static void mas_dfs_preorder(struct ma_s
struct maple_enode *prev;
unsigned char end, slot = 0;
+ unsigned long *pivots;
if (mas->node == MAS_START) {
mas_start(mas);
@@ -35291,6 +35292,9 @@ walk_up:
mas_ascend(mas);
goto walk_up;
}
+ pivots = ma_pivots(mte_to_node(prev), mte_node_type(prev));
+ mas->max = mas_safe_pivot(mas, pivots, slot, mte_node_type(prev));
+ mas->min = mas_safe_min(mas, pivots, slot);
return;
done:
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are
mm-mprotect-fix-do_mprotect_pkey-limit-check.patch
maple_tree-add-benchmarking-for-mas_for_each.patch
maple_tree-add-benchmarking-for-mas_prev.patch
mm-move-unmap_vmas-declaration-to-internal-header.patch
mm-change-do_vmi_align_munmap-side-tree-index.patch
mm-remove-prev-check-from-do_vmi_align_munmap.patch
maple_tree-introduce-__mas_set_range.patch
mm-remove-re-walk-from-mmap_region.patch
maple_tree-re-introduce-entry-to-mas_preallocate-arguments.patch
mm-use-vma_iter_clear_gfp-in-nommu.patch
mm-set-up-vma-iterator-for-vma_iter_prealloc-calls.patch
maple_tree-move-mas_wr_end_piv-below-mas_wr_extend_null.patch
maple_tree-update-mas_preallocate-testing.patch
maple_tree-refine-mas_preallocate-node-calculations.patch
mm-mmap-change-vma-iteration-order-in-do_vmi_align_munmap.patch
userfaultfd-fix-regression-in-userfaultfd_unmap_prep.patch
