On 9/3/24 16:20, Christian Brauner wrote:
> Now that we pass down struct kmem_cache_args to calculate_sizes() we
> don't need it anymore.
Nit: that sounds like a previous patch did the "pass down" part? Fine to do
both at once but maybe adjust description that we do both here?
>
> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
> ---
> mm/slab.h | 2 --
> mm/slub.c | 25 +++++++------------------
> 2 files changed, 7 insertions(+), 20 deletions(-)
>
> diff --git a/mm/slab.h b/mm/slab.h
> index c7a4e0fc3cf1..36ac38e21fcb 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -261,8 +261,6 @@ struct kmem_cache {
> unsigned int object_size; /* Object size without metadata */
> struct reciprocal_value reciprocal_size;
> unsigned int offset; /* Free pointer offset */
> - /* Specific free pointer requested (if not UINT_MAX) */
> - unsigned int rcu_freeptr_offset;
> #ifdef CONFIG_SLUB_CPU_PARTIAL
> /* Number of per cpu partial objects to keep around */
> unsigned int cpu_partial;
> diff --git a/mm/slub.c b/mm/slub.c
> index 4719b60215b8..a23c7036cd61 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -3916,8 +3916,7 @@ static void *__slab_alloc_node(struct kmem_cache *s,
> * If the object has been wiped upon free, make sure it's fully initialized by
> * zeroing out freelist pointer.
> *
> - * Note that we also wipe custom freelist pointers specified via
> - * s->rcu_freeptr_offset.
> + * Note that we also wipe custom freelist pointers.
> */
> static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s,
> void *obj)
> @@ -5141,17 +5140,11 @@ static void set_cpu_partial(struct kmem_cache *s)
> #endif
> }
>
> -/* Was a valid freeptr offset requested? */
> -static inline bool has_freeptr_offset(const struct kmem_cache *s)
> -{
> - return s->rcu_freeptr_offset != UINT_MAX;
> -}
> -
> /*
> * calculate_sizes() determines the order and the distribution of data within
> * a slab object.
> */
> -static int calculate_sizes(struct kmem_cache *s)
> +static int calculate_sizes(struct kmem_cache_args *args, struct kmem_cache *s)
> {
> slab_flags_t flags = s->flags;
> unsigned int size = s->object_size;
> @@ -5192,7 +5185,7 @@ static int calculate_sizes(struct kmem_cache *s)
> */
> s->inuse = size;
>
> - if (((flags & SLAB_TYPESAFE_BY_RCU) && !has_freeptr_offset(s)) ||
> + if (((flags & SLAB_TYPESAFE_BY_RCU) && !args->use_freeptr_offset) ||
> (flags & SLAB_POISON) || s->ctor ||
> ((flags & SLAB_RED_ZONE) &&
> (s->object_size < sizeof(void *) || slub_debug_orig_size(s)))) {
> @@ -5214,8 +5207,8 @@ static int calculate_sizes(struct kmem_cache *s)
> */
> s->offset = size;
> size += sizeof(void *);
> - } else if ((flags & SLAB_TYPESAFE_BY_RCU) && has_freeptr_offset(s)) {
> - s->offset = s->rcu_freeptr_offset;
> + } else if ((flags & SLAB_TYPESAFE_BY_RCU) && args->use_freeptr_offset) {
> + s->offset = args->freeptr_offset;
> } else {
> /*
> * Store freelist pointer near middle of object to keep
> @@ -5856,10 +5849,6 @@ int do_kmem_cache_create(struct kmem_cache *s, const char *name,
> #ifdef CONFIG_SLAB_FREELIST_HARDENED
> s->random = get_random_long();
> #endif
> - if (args->use_freeptr_offset)
> - s->rcu_freeptr_offset = args->freeptr_offset;
> - else
> - s->rcu_freeptr_offset = UINT_MAX;
> s->align = args->align;
> s->ctor = args->ctor;
> #ifdef CONFIG_HARDENED_USERCOPY
> @@ -5867,7 +5856,7 @@ int do_kmem_cache_create(struct kmem_cache *s, const char *name,
> s->usersize = args->usersize;
> #endif
>
> - if (!calculate_sizes(s))
> + if (!calculate_sizes(args, s))
> goto out;
> if (disable_higher_order_debug) {
> /*
> @@ -5877,7 +5866,7 @@ int do_kmem_cache_create(struct kmem_cache *s, const char *name,
> if (get_order(s->size) > get_order(s->object_size)) {
> s->flags &= ~DEBUG_METADATA_FLAGS;
> s->offset = 0;
> - if (!calculate_sizes(s))
> + if (!calculate_sizes(args, s))
> goto out;
> }
> }
>
