On 10/24/23 11:33, chengming.zhou@xxxxxxxxx wrote:
> From: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
>
> Now the partial slub will be frozen when taken out of node partial list,
partially empty slab
> so the __slab_free() will know from "was_frozen" that the partial slab
> is not on node partial list and is used by one kmem_cache_cpu.
... is a cpu or cpu partial slab of some cpu.
> But we will change this, make partial slabs leave the node partial list
> with unfrozen state, so we need to change __slab_free() to use the new
> slab_test_node_partial() we just introduced.
>
> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
> ---
> mm/slub.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/mm/slub.c b/mm/slub.c
> index 3fad4edca34b..f568a32d7332 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -3610,6 +3610,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
> unsigned long counters;
> struct kmem_cache_node *n = NULL;
> unsigned long flags;
> + bool on_node_partial;
>
> stat(s, FREE_SLOWPATH);
>
> @@ -3657,6 +3658,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
> */
> spin_lock_irqsave(&n->list_lock, flags);
>
> + on_node_partial = slab_test_node_partial(slab);
> }
> }
>
> @@ -3685,6 +3687,15 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
> return;
> }
>
> + /*
> + * This slab was partial but not on the per-node partial list,
This slab was partially empty ...
Otherwise LGTM!
> + * in which case we shouldn't manipulate its list, just return.
> + */
> + if (prior && !on_node_partial) {
> + spin_unlock_irqrestore(&n->list_lock, flags);
> + return;
> + }
> +
> if (unlikely(!new.inuse && n->nr_partial >= s->min_partial))
> goto slab_empty;
>
