Re: [PATCH v4 3/5] mm: convert compaction to zone lock wrappers

From: David Hildenbrand (Arm)

Date: Fri Feb 27 2026 - 15:42:10 EST


On 2/27/26 17:00, Dmitry Ilvokhin wrote:
> Compaction uses compact_lock_irqsave(), which currently operates
> on a raw spinlock_t pointer so it can be used for both zone->lock
> and lruvec->lru_lock. Since zone lock operations are now wrapped,
> compact_lock_irqsave() can no longer directly operate on a
> spinlock_t when the lock belongs to a zone.
>
> Split the helper into compact_zone_lock_irqsave() and
> compact_lruvec_lock_irqsave(), duplicating the small amount of
> shared logic. As there are only two call sites and both statically
> know the lock type, this avoids introducing additional abstraction
> or runtime dispatch in the compaction path.
>
> No functional change intended.
>
> Signed-off-by: Dmitry Ilvokhin <d@xxxxxxxxxxxx>
> Acked-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
> ---
> mm/compaction.c | 33 ++++++++++++++++++++++++---------
> 1 file changed, 24 insertions(+), 9 deletions(-)
>
> diff --git a/mm/compaction.c b/mm/compaction.c
> index fa0e332a8a92..c68fcc416fc7 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -503,19 +503,36 @@ static bool test_and_set_skip(struct compact_control *cc, struct page *page)
> *
> * Always returns true which makes it easier to track lock state in callers.
> */
> -static bool compact_lock_irqsave(spinlock_t *lock, unsigned long *flags,
> - struct compact_control *cc)
> - __acquires(lock)
> +static bool compact_zone_lock_irqsave(struct zone *zone,
> + unsigned long *flags,
> + struct compact_control *cc)

... two tabs :)

Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>

--
Cheers,

David