On Thu 18-07-19 14:08:27, Waiman Long wrote:
> The memcg_cache_params structure is only embedded into the kmem_cache
> of slab and slub allocators as defined in slab_def.h and slub_def.h
> and used internally by mm code. There is no needed to expose it in
> a public header. So move it from include/linux/slab.h to mm/slab.h.
> It is just a refactoring patch with no code change.
No objection from me. As long as this survives all weird config
combinations and implicit header files dependencies...
> In fact both the slub_def.h and slab_def.h should be moved into the mm
> directory as well, but that will probably cause many merge conflicts.
>
> Signed-off-by: Waiman Long <long...@redhat.com>
> ---
> include/linux/slab.h | 62 -------------------------------------------
> mm/slab.h | 63 ++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 63 insertions(+), 62 deletions(-)
>
> diff --git a/include/linux/slab.h b/include/linux/slab.h
> index 56c9c7eed34e..ab2b98ad76e1 100644
> --- a/include/linux/slab.h
> +++ b/include/linux/slab.h
> @@ -595,68 +595,6 @@ static __always_inline void *kmalloc_node(size_t size,
> gfp_t flags, int node)
> return __kmalloc_node(size, flags, node);
> }
>
> -struct memcg_cache_array {
> - struct rcu_head rcu;
> - struct kmem_cache *entries[0];
> -};
> -
> -/*
> - * This is the main placeholder for memcg-related information in kmem caches.
> - * Both the root cache and the child caches will have it. For the root cache,
> - * this will hold a dynamically allocated array large enough to hold
> - * information about the currently limited memcgs in the system. To allow the
> - * array to be accessed without taking any locks, on relocation we free the
> old
> - * version only after a grace period.
> - *
> - * Root and child caches hold different metadata.
> - *
> - * @root_cache: Common to root and child caches. NULL for root,
> pointer to
> - * the root cache for children.
> - *
> - * The following fields are specific to root caches.
> - *
> - * @memcg_caches: kmemcg ID indexed table of child caches. This table is
> - * used to index child cachces during allocation and cleared
> - * early during shutdown.
> - *
> - * @root_caches_node: List node for slab_root_caches list.
> - *
> - * @children: List of all child caches. While the child caches are
> also
> - * reachable through @memcg_caches, a child cache remains on
> - * this list until it is actually destroyed.
> - *
> - * The following fields are specific to child caches.
> - *
> - * @memcg: Pointer to the memcg this cache belongs to.
> - *
> - * @children_node: List node for @root_cache->children list.
> - *
> - * @kmem_caches_node: List node for @memcg->kmem_caches list.
> - */
> -struct memcg_cache_params {
> - struct kmem_cache *root_cache;
> - union {
> - struct {
> - struct memcg_cache_array __rcu *memcg_caches;
> - struct list_head __root_caches_node;
> - struct list_head children;
> - bool dying;
> - };
> - struct {
> - struct mem_cgroup *memcg;
> - struct list_head children_node;
> - struct list_head kmem_caches_node;
> - struct percpu_ref refcnt;
> -
> - void (*work_fn)(struct kmem_cache *);
> - union {
> - struct rcu_head rcu_head;
> - struct work_struct work;
> - };
> - };
> - };
> -};
> -
> int memcg_update_all_caches(int num_memcgs);
>
> /**
> diff --git a/mm/slab.h b/mm/slab.h
> index 5bf615cb3f99..68e455f2b698 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -30,6 +30,69 @@ struct kmem_cache {
> struct list_head list; /* List of all slab caches on the system */
> };
>
> +#else /* !CONFIG_SLOB */
> +
> +struct memcg_cache_array {
> + struct rcu_head rcu;
> + struct kmem_cache *entries[0];
> +};
> +
> +/*
> + * This is the main placeholder for memcg-related information in kmem caches.
> + * Both the root cache and the child caches will have it. For the root cache,
> + * this will hold a dynamically allocated array large enough to hold
> + * information about the currently limited memcgs in the system. To allow the
> + * array to be accessed without taking any locks, on relocation we free the
> old
> + * version only after a grace period.
> + *
> + * Root and child caches hold different metadata.
> + *
> + * @root_cache: Common to root and child caches. NULL for root,
> pointer to
> + * the root cache for children.
> + *
> + * The following fields are specific to root caches.
> + *
> + * @memcg_caches: kmemcg ID indexed table of child caches. This table is
> + * used to index child cachces during allocation and cleared
> + * early during shutdown.
> + *
> + * @root_caches_node: List node for slab_root_caches list.
> + *
> + * @children: List of all child caches. While the child caches are
> also
> + * reachable through @memcg_caches, a child cache remains on
> + * this list until it is actually destroyed.
> + *
> + * The following fields are specific to child caches.
> + *
> + * @memcg: Pointer to the memcg this cache belongs to.
> + *
> + * @children_node: List node for @root_cache->children list.
> + *
> + * @kmem_caches_node: List node for @memcg->kmem_caches list.
> + */
> +struct memcg_cache_params {
> + struct kmem_cache *root_cache;
> + union {
> + struct {
> + struct memcg_cache_array __rcu *memcg_caches;
> + struct list_head __root_caches_node;
> + struct list_head children;
> + bool dying;
> + };
> + struct {
> + struct mem_cgroup *memcg;
> + struct list_head children_node;
> + struct list_head kmem_caches_node;
> + struct percpu_ref refcnt;
> +
> + void (*work_fn)(struct kmem_cache *);
> + union {
> + struct rcu_head rcu_head;
> + struct work_struct work;
> + };
> + };
> + };
> +};
> #endif /* CONFIG_SLOB */
>
> #ifdef CONFIG_SLAB
> --
> 2.18.1
--
Michal Hocko
SUSE Labs
