* Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> [231009 16:16]:
> Preallocate maple nodes before call to mas_wr_store_entry(). If a new
> node is not needed, go directly to mas_wr_store_entry(), otherwise
> allocate the needed nodes and set the MA_STATE_PREALLOC flag.
The way I'd like to see this working is to preallocate nodes prior to
writing, but also to end in a state where we can call the store
operation to continue the operation. Both of these parts need to be
together in a patch set if they cannot be in the same patch.
Thanks,
Liam
>
> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
> ---
> lib/maple_tree.c | 22 +++++++++++++++++++---
> 1 file changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index e239197a57fc..25ae66e585f4 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -5478,17 +5478,33 @@ int mas_prealloc_calc(struct ma_wr_state *wr_mas)
> int mas_store_gfp(struct ma_state *mas, void *entry, gfp_t gfp)
> {
> MA_WR_STATE(wr_mas, mas, entry);
> + int request;
>
> mas_wr_store_setup(&wr_mas);
> - trace_ma_write(__func__, mas, 0, entry);
> -retry:
> + wr_mas.content = mas_start(mas);
> +
> + request = mas_prealloc_calc(&wr_mas);
> + if (!request)
> + goto store_entry;
> +
> + mas_node_count_gfp(mas, request, gfp);
> + if (unlikely(mas_is_err(mas))) {
> + mas_set_alloc_req(mas, 0);
> + mas_destroy(mas);
> + mas_reset(mas);
> + return xa_err(mas->node);
> + }
> + mas->mas_flags |= MA_STATE_PREALLOC;
> +
> +store_entry:
> mas_wr_store_entry(&wr_mas);
> if (unlikely(mas_nomem(mas, gfp)))
> - goto retry;
> + goto store_entry;
>
> if (unlikely(mas_is_err(mas)))
> return xa_err(mas->node);
>
> + trace_ma_write(__func__, mas, 0, entry);
> return 0;
> }
> EXPORT_SYMBOL_GPL(mas_store_gfp);
> --
> 2.41.0
>
