korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-16 15:34:48 +08:00
Code Issues Packages Projects Releases Wiki Activity

maple_tree: mtree_range_walk() clean up

Browse Source 
mtree_range_walk() needed to be updated to avoid checking if there was a
pivot value.  On closer examination, the code could avoid setting min or
max in certain scenarios.  The commit removes the extra check for
pivot[offset] before setting max and only sets max when necessary.  It
also only sets min if it is necessary by checking offset 0 prior to the
loop (as it has always done).

The commit also drops a dead node check since the end of the node will
return the array size when the last slot is occupied (by a potential reuse
in a dead node).  The data will be discarded later if the node is marked
dead.

Benchmarking these changes results in an increase in performance of 5.45%
using the BENCH_WALK in the maple tree test code.

Link: https://lkml.kernel.org/r/20231101171629.3612299-13-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Liam R. Howlett 2023-11-01 13:16:29 -04:00 committed by Andrew Morton
parent 24662decdd
commit a3c63c8c5d
1 changed files with 12 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
lib/maple_tree.c
View File

@ -2806,32 +2806,29 @@ static inline void *mtree_range_walk(struct ma_state *mas)
min = mas->min;
max = mas->max;
do {
offset = 0;
last = next;
node = mte_to_node(next);
type = mte_node_type(next);
pivots = ma_pivots(node, type);
end = ma_data_end(node, type, pivots, max);
if (unlikely(ma_dead_node(node)))
goto dead_node;
if (pivots[offset] >= mas->index) {
prev_max = max;
prev_min = min;
max = pivots[offset];
prev_min = min;
prev_max = max;
if (pivots[0] >= mas->index) {
offset = 0;
max = pivots[0];
goto next;
}
do {
offset = 1;
while (offset < end) {
if (pivots[offset] >= mas->index) {
max = pivots[offset];
break;
}
offset++;
} while ((offset < end) && (pivots[offset] < mas->index));
}
prev_min = min;
min = pivots[offset - 1] + 1;
prev_max = max;
if (likely(offset < end && pivots[offset]))
max = pivots[offset];
next:
slots = ma_slots(node, type);
next = mt_slot(mas->tree, slots, offset);