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, 8 insertions, 223 deletions

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 8d431193c273..238293b1dbe1 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -21,6 +21,7 @@
 #include <linux/swiotlb.h>
 #include <linux/proc_fs.h>
 #include <linux/debugfs.h>
+#include <linux/kmemleak.h>
 #include <linux/kasan.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
@@ -71,10 +72,8 @@ static int __init setup_slab_merge(char *str)
 	return 1;
 }
 
-#ifdef CONFIG_SLUB
 __setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
 __setup_param("slub_merge", slub_merge, setup_slab_merge, 0);
-#endif
 
 __setup("slab_nomerge", setup_slab_nomerge);
 __setup("slab_merge", setup_slab_merge);
@@ -197,10 +196,6 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align,
 		if (s->size - size >= sizeof(void *))
 			continue;
 
-		if (IS_ENABLED(CONFIG_SLAB) && align &&
-			(align > s->align || s->align % align))
-			continue;
-
 		return s;
 	}
 	return NULL;
@@ -670,7 +665,7 @@ EXPORT_SYMBOL(random_kmalloc_seed);
  * of two cache sizes there. The size of larger slabs can be determined using
  * fls.
  */
-static u8 size_index[24] __ro_after_init = {
+u8 kmalloc_size_index[24] __ro_after_init = {
 	3,	/* 8 */
 	4,	/* 16 */
 	5,	/* 24 */
@@ -697,33 +692,6 @@ static u8 size_index[24] __ro_after_init = {
 	2	/* 192 */
 };
 
-static inline unsigned int size_index_elem(unsigned int bytes)
-{
-	return (bytes - 1) / 8;
-}
-
-/*
- * Find the kmem_cache structure that serves a given size of
- * allocation
- */
-struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags, unsigned long caller)
-{
-	unsigned int index;
-
-	if (size <= 192) {
-		if (!size)
-			return ZERO_SIZE_PTR;
-
-		index = size_index[size_index_elem(size)];
-	} else {
-		if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE))
-			return NULL;
-		index = fls(size - 1);
-	}
-
-	return kmalloc_caches[kmalloc_type(flags, caller)][index];
-}
-
 size_t kmalloc_size_roundup(size_t size)
 {
 	if (size && size <= KMALLOC_MAX_CACHE_SIZE) {
@@ -848,9 +816,9 @@ void __init setup_kmalloc_cache_index_table(void)
 	for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
 		unsigned int elem = size_index_elem(i);
 
-		if (elem >= ARRAY_SIZE(size_index))
+		if (elem >= ARRAY_SIZE(kmalloc_size_index))
 			break;
-		size_index[elem] = KMALLOC_SHIFT_LOW;
+		kmalloc_size_index[elem] = KMALLOC_SHIFT_LOW;
 	}
 
 	if (KMALLOC_MIN_SIZE >= 64) {
@@ -859,7 +827,7 @@ void __init setup_kmalloc_cache_index_table(void)
 		 * is 64 byte.
 		 */
 		for (i = 64 + 8; i <= 96; i += 8)
-			size_index[size_index_elem(i)] = 7;
+			kmalloc_size_index[size_index_elem(i)] = 7;
 
 	}
 
@@ -870,7 +838,7 @@ void __init setup_kmalloc_cache_index_table(void)
 		 * instead.
 		 */
 		for (i = 128 + 8; i <= 192; i += 8)
-			size_index[size_index_elem(i)] = 8;
+			kmalloc_size_index[size_index_elem(i)] = 8;
 	}
 }
 
@@ -968,95 +936,6 @@ void __init create_kmalloc_caches(slab_flags_t flags)
 	slab_state = UP;
 }
 
-void free_large_kmalloc(struct folio *folio, void *object)
-{
-	unsigned int order = folio_order(folio);
-
-	if (WARN_ON_ONCE(order == 0))
-		pr_warn_once("object pointer: 0x%p\n", object);
-
-	kmemleak_free(object);
-	kasan_kfree_large(object);
-	kmsan_kfree_large(object);
-
-	mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B,
-			      -(PAGE_SIZE << order));
-	__free_pages(folio_page(folio, 0), order);
-}
-
-static void *__kmalloc_large_node(size_t size, gfp_t flags, int node);
-static __always_inline
-void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
-{
-	struct kmem_cache *s;
-	void *ret;
-
-	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
-		ret = __kmalloc_large_node(size, flags, node);
-		trace_kmalloc(caller, ret, size,
-			      PAGE_SIZE << get_order(size), flags, node);
-		return ret;
-	}
-
-	s = kmalloc_slab(size, flags, caller);
-
-	if (unlikely(ZERO_OR_NULL_PTR(s)))
-		return s;
-
-	ret = __kmem_cache_alloc_node(s, flags, node, size, caller);
-	ret = kasan_kmalloc(s, ret, size, flags);
-	trace_kmalloc(caller, ret, size, s->size, flags, node);
-	return ret;
-}
-
-void *__kmalloc_node(size_t size, gfp_t flags, int node)
-{
-	return __do_kmalloc_node(size, flags, node, _RET_IP_);
-}
-EXPORT_SYMBOL(__kmalloc_node);
-
-void *__kmalloc(size_t size, gfp_t flags)
-{
-	return __do_kmalloc_node(size, flags, NUMA_NO_NODE, _RET_IP_);
-}
-EXPORT_SYMBOL(__kmalloc);
-
-void *__kmalloc_node_track_caller(size_t size, gfp_t flags,
-				  int node, unsigned long caller)
-{
-	return __do_kmalloc_node(size, flags, node, caller);
-}
-EXPORT_SYMBOL(__kmalloc_node_track_caller);
-
-/**
- * kfree - free previously allocated memory
- * @object: pointer returned by kmalloc() or kmem_cache_alloc()
- *
- * If @object is NULL, no operation is performed.
- */
-void kfree(const void *object)
-{
-	struct folio *folio;
-	struct slab *slab;
-	struct kmem_cache *s;
-
-	trace_kfree(_RET_IP_, object);
-
-	if (unlikely(ZERO_OR_NULL_PTR(object)))
-		return;
-
-	folio = virt_to_folio(object);
-	if (unlikely(!folio_test_slab(folio))) {
-		free_large_kmalloc(folio, (void *)object);
-		return;
-	}
-
-	slab = folio_slab(folio);
-	s = slab->slab_cache;
-	__kmem_cache_free(s, (void *)object, _RET_IP_);
-}
-EXPORT_SYMBOL(kfree);
-
 /**
  * __ksize -- Report full size of underlying allocation
  * @object: pointer to the object
@@ -1093,30 +972,6 @@ size_t __ksize(const void *object)
 	return slab_ksize(folio_slab(folio)->slab_cache);
 }
 
-void *kmalloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
-{
-	void *ret = __kmem_cache_alloc_node(s, gfpflags, NUMA_NO_NODE,
-					    size, _RET_IP_);
-
-	trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, NUMA_NO_NODE);
-
-	ret = kasan_kmalloc(s, ret, size, gfpflags);
-	return ret;
-}
-EXPORT_SYMBOL(kmalloc_trace);
-
-void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags,
-			 int node, size_t size)
-{
-	void *ret = __kmem_cache_alloc_node(s, gfpflags, node, size, _RET_IP_);
-
-	trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags, node);
-
-	ret = kasan_kmalloc(s, ret, size, gfpflags);
-	return ret;
-}
-EXPORT_SYMBOL(kmalloc_node_trace);
-
 gfp_t kmalloc_fix_flags(gfp_t flags)
 {
 	gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK;
@@ -1129,57 +984,6 @@ gfp_t kmalloc_fix_flags(gfp_t flags)
 	return flags;
 }
 
-/*
- * To avoid unnecessary overhead, we pass through large allocation requests
- * directly to the page allocator. We use __GFP_COMP, because we will need to
- * know the allocation order to free the pages properly in kfree.
- */
-
-static void *__kmalloc_large_node(size_t size, gfp_t flags, int node)
-{
-	struct page *page;
-	void *ptr = NULL;
-	unsigned int order = get_order(size);
-
-	if (unlikely(flags & GFP_SLAB_BUG_MASK))
-		flags = kmalloc_fix_flags(flags);
-
-	flags |= __GFP_COMP;
-	page = alloc_pages_node(node, flags, order);
-	if (page) {
-		ptr = page_address(page);
-		mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
-				      PAGE_SIZE << order);
-	}
-
-	ptr = kasan_kmalloc_large(ptr, size, flags);
-	/* As ptr might get tagged, call kmemleak hook after KASAN. */
-	kmemleak_alloc(ptr, size, 1, flags);
-	kmsan_kmalloc_large(ptr, size, flags);
-
-	return ptr;
-}
-
-void *kmalloc_large(size_t size, gfp_t flags)
-{
-	void *ret = __kmalloc_large_node(size, flags, NUMA_NO_NODE);
-
-	trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << get_order(size),
-		      flags, NUMA_NO_NODE);
-	return ret;
-}
-EXPORT_SYMBOL(kmalloc_large);
-
-void *kmalloc_large_node(size_t size, gfp_t flags, int node)
-{
-	void *ret = __kmalloc_large_node(size, flags, node);
-
-	trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << get_order(size),
-		      flags, node);
-	return ret;
-}
-EXPORT_SYMBOL(kmalloc_large_node);
-
 #ifdef CONFIG_SLAB_FREELIST_RANDOM
 /* Randomize a generic freelist */
 static void freelist_randomize(unsigned int *list,
@@ -1222,12 +1026,8 @@ void cache_random_seq_destroy(struct kmem_cache *cachep)
 }
 #endif /* CONFIG_SLAB_FREELIST_RANDOM */
 
-#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
-#ifdef CONFIG_SLAB
-#define SLABINFO_RIGHTS (0600)
-#else
+#ifdef CONFIG_SLUB_DEBUG
 #define SLABINFO_RIGHTS (0400)
-#endif
 
 static void print_slabinfo_header(struct seq_file *m)
 {
@@ -1235,18 +1035,10 @@ static void print_slabinfo_header(struct seq_file *m)
 	 * Output format version, so at least we can change it
 	 * without _too_ many complaints.
 	 */
-#ifdef CONFIG_DEBUG_SLAB
-	seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
-#else
 	seq_puts(m, "slabinfo - version: 2.1\n");
-#endif
 	seq_puts(m, "# name            <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab>");
 	seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
 	seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
-#ifdef CONFIG_DEBUG_SLAB
-	seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> <error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
-	seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
-#endif
 	seq_putc(m, '\n');
 }
 
@@ -1370,7 +1162,7 @@ static int __init slab_proc_init(void)
 }
 module_init(slab_proc_init);
 
-#endif /* CONFIG_SLAB || CONFIG_SLUB_DEBUG */
+#endif /* CONFIG_SLUB_DEBUG */
 
 static __always_inline __realloc_size(2) void *
 __do_krealloc(const void *p, size_t new_size, gfp_t flags)
@@ -1488,10 +1280,3 @@ EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
 EXPORT_TRACEPOINT_SYMBOL(kfree);
 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);
 
-int should_failslab(struct kmem_cache *s, gfp_t gfpflags)
-{
-	if (__should_failslab(s, gfpflags))
-		return -ENOMEM;
-	return 0;
-}
-ALLOW_ERROR_INJECTION(should_failslab, ERRNO);