Re: [PATCH] maple_tree: Mark three functions as __maybe_unused

From: Kuan-Wei Chiu
Date: Sat Sep 07 2024 - 15:16:42 EST


On Sat, Sep 07, 2024 at 07:31:14PM +0100, Lorenzo Stoakes wrote:
> On Fri, Sep 06, 2024 at 10:15:06PM GMT, Liam R. Howlett wrote:
> > People keep trying to remove three functions that are going to be used
> > in a feature that is being developed. Dropping the functions entirely
> > may end up with people trying to use the bit for other uses, as people
> > have tried in the past.
> >
> > Adding __maybe_unused stops compilers complaining about the unused
> > functions so they can be silently optimised out of the compiled code and
> > people won't try to claim the bit for another use.
> >
> > Link: https://lore.kernel.org/all/20230726080916.17454-2-zhangpeng.00@xxxxxxxxxxxxx/
> > Link: https://lore.kernel.org/all/202408310728.S7EE59BN-lkp@xxxxxxxxx/
> > Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
>
> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>

Thank you for solving the compilation warning!

Reviewed-by: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>

Regards,
Kuan-Wei
>
> > ---
> > lib/maple_tree.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> > index 4f34e50c92b5..20990ecba2dd 100644
> > --- a/lib/maple_tree.c
> > +++ b/lib/maple_tree.c
> > @@ -348,17 +348,17 @@ static inline void *mte_safe_root(const struct maple_enode *node)
> > return (void *)((unsigned long)node & ~MAPLE_ROOT_NODE);
> > }
> >
> > -static inline void *mte_set_full(const struct maple_enode *node)
> > +static inline void __maybe_unused *mte_set_full(const struct maple_enode *node)
> > {
> > return (void *)((unsigned long)node & ~MAPLE_ENODE_NULL);
> > }
> >
> > -static inline void *mte_clear_full(const struct maple_enode *node)
> > +static inline void __maybe_unused *mte_clear_full(const struct maple_enode *node)
> > {
> > return (void *)((unsigned long)node | MAPLE_ENODE_NULL);
> > }
> >
> > -static inline bool mte_has_null(const struct maple_enode *node)
> > +static inline bool __maybe_unused mte_has_null(const struct maple_enode *node)
> > {
> > return (unsigned long)node & MAPLE_ENODE_NULL;
> > }
> > --
> > 2.43.0
> >
>