On 4/11/22 09:25, JaeSang Yoo wrote:
> setup_object_debug() and setup_object() has unused parameter, "struct
> slab *slab". Remove it.
>
> By the commit 3ec0974210fe ("SLUB: Simplify debug code"),
> setup_object_debug() were introduced to refactor previous code blocks
> in the setup_object(). Previous code used SlabDebug() to init_object()
> and init_tracking(). As the SlabDebug() takes "struct page *page" as
> argument, the setup_object_debug() checks flag of "struct kmem_cache *s"
> which doesn't require "struct page *page".
> As the struct page were changed into struct slab by commit bb192ed9aa719
> ("mm/slub: Convert most struct page to struct slab by spatch"), but it's
> still unused parameter.
>
> Suggested-by: Ohhoon Kwon <ohkwon1043@xxxxxxxxx>
> Signed-off-by: JaeSang Yoo <jsyoo5b@xxxxxxxxx>
Thanks, added.
> ---
> mm/slub.c | 19 ++++++++-----------
> 1 file changed, 8 insertions(+), 11 deletions(-)
>
> diff --git a/mm/slub.c b/mm/slub.c
> index 9fe000fd19ca..273bbba74ca1 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -1264,8 +1264,7 @@ static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects)
> }
>
> /* Object debug checks for alloc/free paths */
> -static void setup_object_debug(struct kmem_cache *s, struct slab *slab,
> - void *object)
> +static void setup_object_debug(struct kmem_cache *s, void *object)
> {
> if (!kmem_cache_debug_flags(s, SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON))
> return;
> @@ -1631,8 +1630,7 @@ slab_flags_t kmem_cache_flags(unsigned int object_size,
> return flags | slub_debug_local;
> }
> #else /* !CONFIG_SLUB_DEBUG */
> -static inline void setup_object_debug(struct kmem_cache *s,
> - struct slab *slab, void *object) {}
> +static inline void setup_object_debug(struct kmem_cache *s, void *object) {}
> static inline
> void setup_slab_debug(struct kmem_cache *s, struct slab *slab, void *addr) {}
>
> @@ -1775,10 +1773,9 @@ static inline bool slab_free_freelist_hook(struct kmem_cache *s,
> return *head != NULL;
> }
>
> -static void *setup_object(struct kmem_cache *s, struct slab *slab,
> - void *object)
> +static void *setup_object(struct kmem_cache *s, void *object)
> {
> - setup_object_debug(s, slab, object);
> + setup_object_debug(s, object);
> object = kasan_init_slab_obj(s, object);
> if (unlikely(s->ctor)) {
> kasan_unpoison_object_data(s, object);
> @@ -1897,13 +1894,13 @@ static bool shuffle_freelist(struct kmem_cache *s, struct slab *slab)
> /* First entry is used as the base of the freelist */
> cur = next_freelist_entry(s, slab, &pos, start, page_limit,
> freelist_count);
> - cur = setup_object(s, slab, cur);
> + cur = setup_object(s, cur);
> slab->freelist = cur;
>
> for (idx = 1; idx < slab->objects; idx++) {
> next = next_freelist_entry(s, slab, &pos, start, page_limit,
> freelist_count);
> - next = setup_object(s, slab, next);
> + next = setup_object(s, next);
> set_freepointer(s, cur, next);
> cur = next;
> }
> @@ -1974,11 +1971,11 @@ static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
>
> if (!shuffle) {
> start = fixup_red_left(s, start);
> - start = setup_object(s, slab, start);
> + start = setup_object(s, start);
> slab->freelist = start;
> for (idx = 0, p = start; idx < slab->objects - 1; idx++) {
> next = p + s->size;
> - next = setup_object(s, slab, next);
> + next = setup_object(s, next);
> set_freepointer(s, p, next);
> p = next;
> }
