On Fri, 2025-03-14 at 05:05 +0800, Kemeng Shi wrote:
> Factor out helper swap_entries_put_cache() from put_swap_folio() to server
> as a general-purpose routine for dropping cache flag of entries within a
> single cluster.
>
> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
Reviewed-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
> ---
> mm/swapfile.c | 25 ++++++++++++++++---------
> 1 file changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/mm/swapfile.c b/mm/swapfile.c
> index ebac9ff74ba7..343b34eb2a81 100644
> --- a/mm/swapfile.c
> +++ b/mm/swapfile.c
> @@ -1473,6 +1473,21 @@ struct swap_info_struct *get_swap_device(swp_entry_t entry)
> return NULL;
> }
>
> +static void swap_entries_put_cache(struct swap_info_struct *si,
> + swp_entry_t entry, int nr)
> +{
> + unsigned long offset = swp_offset(entry);
> + struct swap_cluster_info *ci;
> +
> + ci = lock_cluster(si, offset);
> + if (swap_only_has_cache(si, offset, nr))
> + swap_entries_free(si, ci, entry, nr);
> + else
> + for (int i = 0; i < nr; i++, entry.val++)
> + swap_entry_put_locked(si, ci, entry, SWAP_HAS_CACHE);
> + unlock_cluster(ci);
> +}
> +
> static bool swap_entries_put_map(struct swap_info_struct *si,
> swp_entry_t entry, int nr)
> {
> @@ -1597,8 +1612,6 @@ void swap_free_nr(swp_entry_t entry, int nr_pages)
> */
> void put_swap_folio(struct folio *folio, swp_entry_t entry)
> {
> - unsigned long offset = swp_offset(entry);
> - struct swap_cluster_info *ci;
> struct swap_info_struct *si;
> int size = 1 << swap_entry_order(folio_order(folio));
>
> @@ -1606,13 +1619,7 @@ void put_swap_folio(struct folio *folio, swp_entry_t entry)
> if (!si)
> return;
>
> - ci = lock_cluster(si, offset);
> - if (swap_only_has_cache(si, offset, size))
> - swap_entries_free(si, ci, entry, size);
> - else
> - for (int i = 0; i < size; i++, entry.val++)
> - swap_entry_put_locked(si, ci, entry, SWAP_HAS_CACHE);
> - unlock_cluster(ci);
> + swap_entries_put_cache(si, entry, size);
> }
>
> int __swap_count(swp_entry_t entry)
