Re: [PATCH drm-next v4 02/14] maple_tree: split up MA_STATE() macro

From: Liam R. Howlett
Date: Tue Jun 13 2023 - 13:28:48 EST


* Danilo Krummrich <dakr@xxxxxxxxxx> [230606 18:31]:
> Split up the MA_STATE() macro such that components using the maple tree
> can easily inherit from struct ma_state and build custom tree walk
> macros to hide their internals from users.
>
> Example:
>
> struct sample_iterator {
> struct ma_state mas;
> struct sample_mgr *mgr;
> };
>
> \#define SAMPLE_ITERATOR(name, __mgr, start) \
> struct sample_iterator name = { \
> .mas = MA_STATE_INIT(&(__mgr)->mt, start, 0), \
> .mgr = __mgr, \
> }
>
> \#define sample_iter_for_each_range(it__, entry__, end__) \
> mas_for_each(&(it__).mas, entry__, end__)
>
> --
>
> struct sample *sample;
> SAMPLE_ITERATOR(si, min);
>
> sample_iter_for_each_range(&si, sample, max) {
> frob(mgr, sample);
> }
>
> Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>

Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

> ---
> include/linux/maple_tree.h | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
> index 1fadb5f5978b..87d55334f1c2 100644
> --- a/include/linux/maple_tree.h
> +++ b/include/linux/maple_tree.h
> @@ -423,8 +423,8 @@ struct ma_wr_state {
> #define MA_ERROR(err) \
> ((struct maple_enode *)(((unsigned long)err << 2) | 2UL))
>
> -#define MA_STATE(name, mt, first, end) \
> - struct ma_state name = { \
> +#define MA_STATE_INIT(mt, first, end) \
> + { \
> .tree = mt, \
> .index = first, \
> .last = end, \
> @@ -435,6 +435,9 @@ struct ma_wr_state {
> .mas_flags = 0, \
> }
>
> +#define MA_STATE(name, mt, first, end) \
> + struct ma_state name = MA_STATE_INIT(mt, first, end)
> +
> #define MA_WR_STATE(name, ma_state, wr_entry) \
> struct ma_wr_state name = { \
> .mas = ma_state, \
> --
> 2.40.1
>
>