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From:   Liam Howlett <liam.howlett@oracle.com>
To:     Vernon Yang <vernon2gm@gmail.com>
CC:     "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
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Subject: Re: [PATCH 8/8] maple_tree: refine mab_calc_split function
Thread-Topic: [PATCH 8/8] maple_tree: refine mab_calc_split function
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Date:   Tue, 20 Dec 2022 15:05:52 +0000
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* Vernon Yang <vernon2gm@gmail.com> [221220 09:26]:
> Invert the conditional judgment of the mid_split, to focus
> the return statement in the last statement, which is easier
> to understand and for better readability.
>=20
> Signed-off-by: Vernon Yang <vernon2gm@gmail.com>
> ---
>  lib/maple_tree.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>=20
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 16cdcf309e97..d147669fb99c 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -1882,10 +1882,9 @@ static inline int mab_calc_split(struct ma_state *=
mas,
> =20
>  	/* Avoid ending a node on a NULL entry */
>  	split =3D mab_no_null_split(bn, split, slot_count);
> -	if (!(*mid_split))
> -		return split;
> =20
> -	*mid_split =3D mab_no_null_split(bn, *mid_split, slot_count);
> +	if (*mid_split)
> +		*mid_split =3D mab_no_null_split(bn, *mid_split, slot_count);

The function is written this way because mid_split is almost always
zero.  If you want to change this, then we should add an unlikely() to
the if statement.

> =20
>  	return split;
>  }
> --=20
> 2.34.1
>=20
> =