On Tue, Oct 31, 2023 at 11:09 PM <chengming.zhou@xxxxxxxxx> wrote:
>
> From: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
>
> We will have unfrozen slabs out of the node partial list later, so we
> need a freeze_slab() function to freeze the partial slab and get its
> freelist.
>
> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
> Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
> ---
> mm/slub.c | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/mm/slub.c b/mm/slub.c
> index 1880b483350e..edf567971679 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -3098,6 +3098,33 @@ static inline void *get_freelist(struct kmem_cache *s, struct slab *slab)
> return freelist;
> }
>
> +/*
> + * Freeze the partial slab and return the pointer to the freelist.
> + */
> +static inline void *freeze_slab(struct kmem_cache *s, struct slab *slab)
> +{
> + struct slab new;
> + unsigned long counters;
> + void *freelist;
> +
> + do {
> + freelist = slab->freelist;
> + counters = slab->counters;
> +
> + new.counters = counters;
> + VM_BUG_ON(new.frozen);
> +
> + new.inuse = slab->objects;
> + new.frozen = 1;
> +
> + } while (!slab_update_freelist(s, slab,
> + freelist, counters,
> + NULL, new.counters,
> + "freeze_slab"));
> +
> + return freelist;
> +}
> +
Looks good to me,
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Thanks!
> /*
> * Slow path. The lockless freelist is empty or we need to perform
> * debugging duties.
> --
> 2.20.1
>
