* Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> [250221 11:36]:
> This allows support for using the vacant height to calculate the worst
> case number of nodes needed for wr_rebalance operation.
> mas_spanning_rebalance() was seen to perform unnecessary node allocations.
> We can reduce allocations by breaking early during the rebalancing loop
> once we realize that we have ascended to a common ancestor.
>
> Suggested-by: Liam Howlett <liam.howlett@xxxxxxxxxx>
> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx>
> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> ---
> lib/maple_tree.c | 19 ++++++++++++++++---
> 1 file changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index ef71af0529f4..4de257003251 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -2896,11 +2896,24 @@ static void mas_spanning_rebalance(struct ma_state *mas,
> mast_combine_cp_right(mast);
> mast->orig_l->last = mast->orig_l->max;
>
> - if (mast_sufficient(mast))
> - continue;
> + if (mast_sufficient(mast)) {
> + if (mast_overflow(mast))
> + continue;
> +
> + if (mast->orig_l->node == mast->orig_r->node) {
> + /*
> + * The data in b_node should be stored in one
> + * node and in the tree
> + */
> + slot = mast->l->offset;
> + /* May be a new root stored in mast->bn */
> + if (mas_is_root_limits(mast->orig_l))
> + new_height++;
> + break;
> + }
>
> - if (mast_overflow(mast))
> continue;
> + }
>
> /* May be a new root stored in mast->bn */
> if (mas_is_root_limits(mast->orig_l)) {
> --
> 2.43.0
>
