On Tue, Mar 14, 2023 at 09:28:32AM +0000, Hyeonggon Yoo wrote:
> On Fri, Mar 10, 2023 at 11:32:07AM +0100, Vlastimil Babka wrote:
> > CONFIG_SLOB has been removed from Kconfig. Remove code and #ifdef's
> > specific to SLOB in the slab headers and common code.
> >
> > Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
> > ---
> > include/linux/slab.h | 39 ----------------------------
> > mm/slab.h | 61 --------------------------------------------
> > mm/slab_common.c | 2 --
> > 3 files changed, 102 deletions(-)
> >
> > diff --git a/include/linux/slab.h b/include/linux/slab.h
> > index 45af70315a94..7f645a4c1298 100644
> > --- a/include/linux/slab.h
> > +++ b/include/linux/slab.h
> > @@ -298,19 +298,6 @@ static inline unsigned int arch_slab_minalign(void)
> > #endif
> > #endif
> >
> > -#ifdef CONFIG_SLOB
> > -/*
> > - * SLOB passes all requests larger than one page to the page allocator.
> > - * No kmalloc array is necessary since objects of different sizes can
> > - * be allocated from the same page.
> > - */
> > -#define KMALLOC_SHIFT_HIGH PAGE_SHIFT
> > -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
> > -#ifndef KMALLOC_SHIFT_LOW
> > -#define KMALLOC_SHIFT_LOW 3
> > -#endif
> > -#endif
> > -
> > /* Maximum allocatable size */
> > #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
> > /* Maximum size for which we actually use a slab cache */
> > @@ -366,7 +353,6 @@ enum kmalloc_cache_type {
> > NR_KMALLOC_TYPES
> > };
> >
> > -#ifndef CONFIG_SLOB
> > extern struct kmem_cache *
> > kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1];
> >
> > @@ -458,7 +444,6 @@ static __always_inline unsigned int __kmalloc_index(size_t size,
> > }
> > static_assert(PAGE_SHIFT <= 20);
> > #define kmalloc_index(s) __kmalloc_index(s, true)
> > -#endif /* !CONFIG_SLOB */
> >
> > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1);
> >
> > @@ -487,10 +472,6 @@ void kmem_cache_free(struct kmem_cache *s, void *objp);
> > void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p);
> > int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
> >
> > -/*
> > - * Caller must not use kfree_bulk() on memory not originally allocated
> > - * by kmalloc(), because the SLOB allocator cannot handle this.
> > - */
> > static __always_inline void kfree_bulk(size_t size, void **p)
> > {
> > kmem_cache_free_bulk(NULL, size, p);
> > @@ -567,7 +548,6 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align
> > * Try really hard to succeed the allocation but fail
> > * eventually.
> > */
> > -#ifndef CONFIG_SLOB
> > static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags)
> > {
> > if (__builtin_constant_p(size) && size) {
> > @@ -583,17 +563,7 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags)
> > }
> > return __kmalloc(size, flags);
> > }
> > -#else
> > -static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags)
> > -{
> > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE)
> > - return kmalloc_large(size, flags);
> > -
> > - return __kmalloc(size, flags);
> > -}
> > -#endif
> >
> > -#ifndef CONFIG_SLOB
> > static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node)
> > {
> > if (__builtin_constant_p(size) && size) {
> > @@ -609,15 +579,6 @@ static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t fla
> > }
> > return __kmalloc_node(size, flags, node);
> > }
> > -#else
> > -static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node)
> > -{
> > - if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE)
> > - return kmalloc_large_node(size, flags, node);
> > -
> > - return __kmalloc_node(size, flags, node);
> > -}
> > -#endif
> >
> > /**
> > * kmalloc_array - allocate memory for an array.
> > diff --git a/mm/slab.h b/mm/slab.h
> > index 43966aa5fadf..399966b3ce52 100644
> > --- a/mm/slab.h
> > +++ b/mm/slab.h
> > @@ -51,14 +51,6 @@ struct slab {
> > };
> > unsigned int __unused;
> >
> > -#elif defined(CONFIG_SLOB)
> > -
> > - struct list_head slab_list;
> > - void *__unused_1;
> > - void *freelist; /* first free block */
> > - long units;
> > - unsigned int __unused_2;
> > -
> > #else
> > #error "Unexpected slab allocator configured"
> > #endif
> > @@ -72,11 +64,7 @@ struct slab {
> > #define SLAB_MATCH(pg, sl) \
> > static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
> > SLAB_MATCH(flags, __page_flags);
> > -#ifndef CONFIG_SLOB
> > SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */
> > -#else
> > -SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */
> > -#endif
> > SLAB_MATCH(_refcount, __page_refcount);
> > #ifdef CONFIG_MEMCG
> > SLAB_MATCH(memcg_data, memcg_data);
> > @@ -200,31 +188,6 @@ static inline size_t slab_size(const struct slab *slab)
> > return PAGE_SIZE << slab_order(slab);
> > }
> >
> > -#ifdef CONFIG_SLOB
> > -/*
> > - * Common fields provided in kmem_cache by all slab allocators
> > - * This struct is either used directly by the allocator (SLOB)
> > - * or the allocator must include definitions for all fields
> > - * provided in kmem_cache_common in their definition of kmem_cache.
> > - *
> > - * Once we can do anonymous structs (C11 standard) we could put a
> > - * anonymous struct definition in these allocators so that the
> > - * separate allocations in the kmem_cache structure of SLAB and
> > - * SLUB is no longer needed.
> > - */
> > -struct kmem_cache {
> > - unsigned int object_size;/* The original size of the object */
> > - unsigned int size; /* The aligned/padded/added on size */
> > - unsigned int align; /* Alignment as calculated */
> > - slab_flags_t flags; /* Active flags on the slab */
> > - const char *name; /* Slab name for sysfs */
> > - int refcount; /* Use counter */
> > - void (*ctor)(void *); /* Called on object slot creation */
> > - struct list_head list; /* List of all slab caches on the system */
> > -};
> > -
> > -#endif /* CONFIG_SLOB */
> > -
> > #ifdef CONFIG_SLAB
> > #include <linux/slab_def.h>
> > #endif
> > @@ -274,7 +237,6 @@ extern const struct kmalloc_info_struct {
> > unsigned int size;
> > } kmalloc_info[];
> >
> > -#ifndef CONFIG_SLOB
> > /* Kmalloc array related functions */
> > void setup_kmalloc_cache_index_table(void);
> > void create_kmalloc_caches(slab_flags_t);
> > @@ -286,7 +248,6 @@ void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags,
> > int node, size_t orig_size,
> > unsigned long caller);
> > void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller);
> > -#endif
> >
> > gfp_t kmalloc_fix_flags(gfp_t flags);
> >
> > @@ -303,33 +264,16 @@ extern void create_boot_cache(struct kmem_cache *, const char *name,
> > int slab_unmergeable(struct kmem_cache *s);
> > struct kmem_cache *find_mergeable(unsigned size, unsigned align,
> > slab_flags_t flags, const char *name, void (*ctor)(void *));
> > -#ifndef CONFIG_SLOB
> > struct kmem_cache *
> > __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
> > slab_flags_t flags, void (*ctor)(void *));
> >
> > slab_flags_t kmem_cache_flags(unsigned int object_size,
> > slab_flags_t flags, const char *name);
> > -#else
> > -static inline struct kmem_cache *
> > -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
> > - slab_flags_t flags, void (*ctor)(void *))
> > -{ return NULL; }
> > -
> > -static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
> > - slab_flags_t flags, const char *name)
> > -{
> > - return flags;
> > -}
> > -#endif
> >
> > static inline bool is_kmalloc_cache(struct kmem_cache *s)
> > {
> > -#ifndef CONFIG_SLOB
> > return (s->flags & SLAB_KMALLOC);
> > -#else
> > - return false;
> > -#endif
> > }
> >
> > /* Legal flag mask for kmem_cache_create(), for various configurations */
> > @@ -634,7 +578,6 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
> > }
> > #endif /* CONFIG_MEMCG_KMEM */
> >
> > -#ifndef CONFIG_SLOB
> > static inline struct kmem_cache *virt_to_cache(const void *obj)
> > {
> > struct slab *slab;
> > @@ -684,8 +627,6 @@ static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
> >
> > void free_large_kmalloc(struct folio *folio, void *object);
> >
> > -#endif /* CONFIG_SLOB */
> > -
> > size_t __ksize(const void *objp);
> >
> > static inline size_t slab_ksize(const struct kmem_cache *s)
> > @@ -777,7 +718,6 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
> > memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
> > }
> >
> > -#ifndef CONFIG_SLOB
> > /*
> > * The slab lists for all objects.
> > */
> > @@ -824,7 +764,6 @@ static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
> > for (__node = 0; __node < nr_node_ids; __node++) \
> > if ((__n = get_node(__s, __node)))
> >
> > -#endif
> >
> > #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
> > void dump_unreclaimable_slab(void);
> > diff --git a/mm/slab_common.c b/mm/slab_common.c
> > index bf4e777cfe90..1522693295f5 100644
> > --- a/mm/slab_common.c
> > +++ b/mm/slab_common.c
> > @@ -625,7 +625,6 @@ void kmem_dump_obj(void *object)
> > EXPORT_SYMBOL_GPL(kmem_dump_obj);
> > #endif
> >
> > -#ifndef CONFIG_SLOB
> > /* Create a cache during boot when no slab services are available yet */
> > void __init create_boot_cache(struct kmem_cache *s, const char *name,
> > unsigned int size, slab_flags_t flags,
> > @@ -1079,7 +1078,6 @@ void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags,
> > return ret;
> > }
> > EXPORT_SYMBOL(kmalloc_node_trace);
> > -#endif /* !CONFIG_SLOB */
> >
> > gfp_t kmalloc_fix_flags(gfp_t flags)
> > {
>
> Looks good to me,
>
> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
>
> > --
> > 2.39.2
> >
Looks good to me too,
Acked-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
