Re: [PATCH v2] mm/swap: Fix swap_cluster_lock() !CONFIG_SWAP stub signature mismatch

From: Kairui Song

Date: Fri Jul 17 2026 - 03:18:23 EST


On Fri, Jul 17, 2026 at 3:13 PM Hongfu Li <hongfu.li@xxxxxxxxx> wrote:
>
> From: Hongfu Li <lihongfu@xxxxxxxxxx>
>
> The !CONFIG_SWAP stub for swap_cluster_lock() has mismatched prototype:
> it has an extra unused irq argument and uses pgoff_t instead of unsigned
> long for offset. All callers are under CONFIG_SWAP so the extra parameter
> is dead.
>
> Delete the unused stub function entirely.
>
> Signed-off-by: Hongfu Li <lihongfu@xxxxxxxxxx>
> Reviewed-by: Baoquan He <baoquan.he@xxxxxxxxx>
> ---
> v2:
> - Drop the stub entirely instead of fixing its signature. All callers are under
> CONFIG_SWAP, so the stub is dead code. (Suggested by Kairui Song)
> - Add Reviewed-by tag
> - Update commit message
> ---
> mm/swap.h | 6 ------
> 1 file changed, 6 deletions(-)
>
> diff --git a/mm/swap.h b/mm/swap.h
> index 77d2d14eda42..d7834888e0d2 100644
> --- a/mm/swap.h
> +++ b/mm/swap.h
> @@ -336,12 +336,6 @@ static inline unsigned int folio_swap_flags(struct folio *folio)
>
> #else /* CONFIG_SWAP */
> struct swap_iocb;
> -static inline struct swap_cluster_info *swap_cluster_lock(
> - struct swap_info_struct *si, pgoff_t offset, bool irq)
> -{
> - return NULL;
> -}
> -
> static inline struct swap_cluster_info *swap_cluster_get_and_lock(
> struct folio *folio)
> {
> --
> 2.54.0
>

Acked-by: Kairui Song <kasong@xxxxxxxxxxx>