In maple_big_node, we define slot and padding/gap in a union. And based
on current definition of MAPLE_BIG_NODE_SLOTS/GAPS, padding is always
less then slot and part of the gap is overlapped by slot.
For example on 64bit system:
MAPLE_BIG_NODE_SLOT is 34
MAPLE_BIG_NODE_GAP is 21
With this knowledge, current code actually clear the whole
maple_big_node and even clear some space twice.
Instead of clear maple_big_node each field separately, let's clear it in
one memset.
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
CC: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
Liam:
This looks obvious, so I just run the ./maple test to see it doesn't
break anything.
Do you think I need to add a benchmark and run a perf for this kind of
change?
---
lib/maple_tree.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index d8f10773e451..911c5e04e634 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3134,10 +3134,7 @@ static inline void mast_fill_bnode(struct maple_subtree_state *mast,
bool cp = true;
unsigned char split;
- memset(mast->bn->gap, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->gap));
- memset(mast->bn->slot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->slot));
- memset(mast->bn->pivot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->pivot));
- mast->bn->b_end = 0;
+ memset(mast->bn, 0, sizeof(struct maple_big_node));
if (mte_is_root(mas->node)) {
cp = false;
--
2.34.1
