Re: [PATCH v2 16/16] maple_tree: remove unneeded mas_wr_walk() in mas_store_prealloc()

From: Liam R. Howlett
Date: Thu Jun 13 2024 - 11:03:13 EST


* Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> [240607 14:53]:
> Users of mas_store_prealloc() enter this function with nodes already
> preallocated. This means the store type must be already set. We can then
> remove the call to mas_wr_store_type() and initialize the write state to
> continue the partial walk that was done when determining the store type.
>
> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
> ---
> lib/maple_tree.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 3d334e7c19a5..5854f25a4ae5 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -4027,9 +4027,6 @@ static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas)
> wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end];
> else
> wr_mas->end_piv = wr_mas->mas->max;
> -
> - if (!wr_mas->entry)
> - mas_wr_extend_null(wr_mas);
> }
>
> static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas)
> @@ -5598,12 +5595,23 @@ void mas_store_prealloc(struct ma_state *mas, void *entry)
> {
> MA_WR_STATE(wr_mas, mas, entry);
>
> - mas_wr_prealloc_setup(&wr_mas);
> - mas_wr_store_type(&wr_mas);
> + if (mas->store_type == wr_store_root) {
> + mas_wr_prealloc_setup(&wr_mas);
> + goto store;
> + }
> +
> + mas_wr_walk_descend(&wr_mas);
> + if (mas->store_type != wr_spanning_store) {
> + /* set wr_mas->content to current slot */
> + wr_mas.content = mas_slot_locked(mas, wr_mas.slots, mas->offset);
> + mas_wr_end_piv(&wr_mas);
> + }
> +store:
> trace_ma_write(__func__, mas, 0, entry);
> mas_wr_store_entry(&wr_mas);
> MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas));
> mas_destroy(mas);
> +

nit, this new line should probably be before the "store" label?

> }
> EXPORT_SYMBOL_GPL(mas_store_prealloc);
>
> --
> 2.45.2
>