Merge tag 'slab-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - SLUB: delayed freezing of CPU partial slabs (Chengming Zhou)

   Freezing is an operation involving double_cmpxchg() that makes a slab
   exclusive for a particular CPU. Chengming noticed that we use it also
   in situations where we are not yet installing the slab as the CPU
   slab, because freezing also indicates that the slab is not on the
   shared list. This results in redundant freeze/unfreeze operation and
   can be avoided by marking separately the shared list presence by
   reusing the PG_workingset flag.

   This approach neatly avoids the issues described in 9b1ea29bc0d7
   ("Revert "mm, slub: consider rest of partial list if acquire_slab()
   fails"") as we can now grab a slab from the shared list in a quick
   and guaranteed way without the cmpxchg_double() operation that
   amplifies the lock contention and can fail.

   As a result, lkp has reported 34.2% improvement of
   stress-ng.rawudp.ops_per_sec

 - SLAB removal and SLUB cleanups (Vlastimil Babka)

   The SLAB allocator has been deprecated since 6.5 and nobody has
   objected so far. We agreed at LSF/MM to wait until the next LTS,
   which is 6.6, so we should be good to go now.

   This doesn't yet erase all traces of SLAB outside of mm/ so some dead
   code, comments or documentation remain, and will be cleaned up
   gradually (some series are already in the works).

   Removing the choice of allocators has already allowed to simplify and
   optimize the code wiring up the kmalloc APIs to the SLUB
   implementation.

* tag 'slab-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (34 commits)
  mm/slub: free KFENCE objects in slab_free_hook()
  mm/slub: handle bulk and single object freeing separately
  mm/slub: introduce __kmem_cache_free_bulk() without free hooks
  mm/slub: fix bulk alloc and free stats
  mm/slub: optimize free fast path code layout
  mm/slub: optimize alloc fastpath code layout
  mm/slub: remove slab_alloc() and __kmem_cache_alloc_lru() wrappers
  mm/slab: move kmalloc() functions from slab_common.c to slub.c
  mm/slab: move kmalloc_slab() to mm/slab.h
  mm/slab: move kfree() from slab_common.c to slub.c
  mm/slab: move struct kmem_cache_node from slab.h to slub.c
  mm/slab: move memcg related functions from slab.h to slub.c
  mm/slab: move pre/post-alloc hooks from slab.h to slub.c
  mm/slab: consolidate includes in the internal mm/slab.h
  mm/slab: move the rest of slub_def.h to mm/slab.h
  mm/slab: move struct kmem_cache_cpu declaration to slub.c
  mm/slab: remove mm/slab.c and slab_def.h
  mm/mempool/dmapool: remove CONFIG_DEBUG_SLAB ifdefs
  mm/slab: remove CONFIG_SLAB code from slab common code
  cpu/hotplug: remove CPUHP_SLAB_PREPARE hooks
  ...

1 files changed, 0 insertions, 124 deletions

diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
deleted file mode 100644
index a61e7d55d0d3..000000000000
--- a/include/linux/slab_def.h
+++ /dev/null
@@ -1,124 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_SLAB_DEF_H
-#define	_LINUX_SLAB_DEF_H
-
-#include <linux/kfence.h>
-#include <linux/reciprocal_div.h>
-
-/*
- * Definitions unique to the original Linux SLAB allocator.
- */
-
-struct kmem_cache {
-	struct array_cache __percpu *cpu_cache;
-
-/* 1) Cache tunables. Protected by slab_mutex */
-	unsigned int batchcount;
-	unsigned int limit;
-	unsigned int shared;
-
-	unsigned int size;
-	struct reciprocal_value reciprocal_buffer_size;
-/* 2) touched by every alloc & free from the backend */
-
-	slab_flags_t flags;		/* constant flags */
-	unsigned int num;		/* # of objs per slab */
-
-/* 3) cache_grow/shrink */
-	/* order of pgs per slab (2^n) */
-	unsigned int gfporder;
-
-	/* force GFP flags, e.g. GFP_DMA */
-	gfp_t allocflags;
-
-	size_t colour;			/* cache colouring range */
-	unsigned int colour_off;	/* colour offset */
-	unsigned int freelist_size;
-
-	/* constructor func */
-	void (*ctor)(void *obj);
-
-/* 4) cache creation/removal */
-	const char *name;
-	struct list_head list;
-	int refcount;
-	int object_size;
-	int align;
-
-/* 5) statistics */
-#ifdef CONFIG_DEBUG_SLAB
-	unsigned long num_active;
-	unsigned long num_allocations;
-	unsigned long high_mark;
-	unsigned long grown;
-	unsigned long reaped;
-	unsigned long errors;
-	unsigned long max_freeable;
-	unsigned long node_allocs;
-	unsigned long node_frees;
-	unsigned long node_overflow;
-	atomic_t allochit;
-	atomic_t allocmiss;
-	atomic_t freehit;
-	atomic_t freemiss;
-
-	/*
-	 * If debugging is enabled, then the allocator can add additional
-	 * fields and/or padding to every object. 'size' contains the total
-	 * object size including these internal fields, while 'obj_offset'
-	 * and 'object_size' contain the offset to the user object and its
-	 * size.
-	 */
-	int obj_offset;
-#endif /* CONFIG_DEBUG_SLAB */
-
-#ifdef CONFIG_KASAN_GENERIC
-	struct kasan_cache kasan_info;
-#endif
-
-#ifdef CONFIG_SLAB_FREELIST_RANDOM
-	unsigned int *random_seq;
-#endif
-
-#ifdef CONFIG_HARDENED_USERCOPY
-	unsigned int useroffset;	/* Usercopy region offset */
-	unsigned int usersize;		/* Usercopy region size */
-#endif
-
-	struct kmem_cache_node *node[MAX_NUMNODES];
-};
-
-static inline void *nearest_obj(struct kmem_cache *cache, const struct slab *slab,
-				void *x)
-{
-	void *object = x - (x - slab->s_mem) % cache->size;
-	void *last_object = slab->s_mem + (cache->num - 1) * cache->size;
-
-	if (unlikely(object > last_object))
-		return last_object;
-	else
-		return object;
-}
-
-/*
- * We want to avoid an expensive divide : (offset / cache->size)
- *   Using the fact that size is a constant for a particular cache,
- *   we can replace (offset / cache->size) by
- *   reciprocal_divide(offset, cache->reciprocal_buffer_size)
- */
-static inline unsigned int obj_to_index(const struct kmem_cache *cache,
-					const struct slab *slab, void *obj)
-{
-	u32 offset = (obj - slab->s_mem);
-	return reciprocal_divide(offset, cache->reciprocal_buffer_size);
-}
-
-static inline int objs_per_slab(const struct kmem_cache *cache,
-				     const struct slab *slab)
-{
-	if (is_kfence_address(slab_address(slab)))
-		return 1;
-	return cache->num;
-}
-
-#endif	/* _LINUX_SLAB_DEF_H */